Forecast Discussions mentioning any of
"HRRR" "RAP" "RR" "RUC13" "RUC" received at GSD on 02/22/15
AREA FORECAST DISCUSSION
NWS SAN JOAQUIN VALLEY - HANFORD CA
1020 PM PST THU FEB 19 2015
.SYNOPSIS...
PATCHY FOG WILL ONCE AGAIN BE POSSIBLE TONIGHT INTO EARLY FRIDAY
MORNING. OTHERWISE...A STORM SYSTEM WILL APPROACH THE REGION DURING
THE SECOND HALF OF THE WEEKEND BRINGING COOLER TEMPERATURES AND A
POSSIBILITY OF RAIN TO MUCH OF THE REGION. DRY WEATHER WILL RETURN TO
THE AREA TUESDAY AND CONTINUE THROUGH THE REST OF THE WORK WEEK.
&&
.DISCUSSION...FORECAST UPDATED TO INCLUDE DENSE FOG FOR MUCH OF
THE VALLEY THROUGH 10 AM FRIDAY. DENSE FOG ADVISORY HAS BEEN
ISSUED WITH VISIBILITY EXPECTED TO FALL TO 200 FEET OR LESS IN
PLACES...SIMILAR TO CONDITIONS OBSERVED EARLY THIS MORNING. FRESNO
WAS ADDED TO THE DENSE FOG ADVISORY...HOWEVER CONFIDENCE IS LOW
GIVEN THEY DID NOT EXPERIENCE DENSE FOG CONDITIONS THIS MORNING.
THE HRRR HAS BEEN PERSISTENT WITH FRESNO FALLING TO A QUARTER MILE
OR LESS BY 2 AM.
&&
.PREV DISCUSSION... /ISSUED 913 PM PST THU FEB 19 2015/
DISCUSSION...THE FORECAST HAS BEEN UPDATED TO INCLUDE THE
POSSIBILITY OF RAIN FOR THE VALLEY AND FOOTHILL LOCATIONS
BEGINNING LATE SUNDAY MORNING AND CONTINUING INTO EARLY MONDAY
MORNING. THE TREND OF THE OPERATIONAL MODELS AND ENSEMBLE MEAN ARE
TRENDING THE UPPER LOW WESTERLY OVER THE WEEKEND...ALLOWING MUCH
OF THE REGION TO BE IMPACTED WITH RAIN. ADDITIONALLY...THE MOD
TREND HAS BEEN TRENDING DEEPER WITH THE UPPER LOW...ADDING A
LITTLE MORE CONFIDENCE TO THIS FORECAST. LASTLY...THE NAEFS
PROBABILITY OF MEASUREABLE PRECIPITATION HAS ALSO BEEN TRENDING
HIGHER FROM MODEL RUN TO MODEL RUN. WE WILL CONTINUE TO MONITOR
THE FORECAST CLOSELY AND FINE TUNE ESPECIALLY IN THE NEXT 36 HOURS
WHEN WE BEGIN TO SEE THE HIGH RES ARW AND NMM DATA.
&&
.AVIATION...
IN THE SAN JOAQUIN VALLEY...AREAS OF IFR WITH LOCAL LIFR/VLIFR
IN FOG CAN BE EXPECTED BETWEEN 08Z AND 18Z FRIDAY. OTHERWISE... MVFR
CONDITIONS WILL PREVAIL IN HAZE DURING THE NEXT 24 HOURS. ELSEWHERE
ACROSS THE CENTRAL CALIFORNIA INTERIOR...VFR CONDITIONS CAN BE
EXPECTED DURING THE NEXT 24 HOURS.
&&
.AIR QUALITY ISSUES...
ON FRIDAY FEBRUARY 20 2015... UNHEALTHY FOR SENSITIVE GROUPS IN
KERN COUNTY. FIREPLACE/WOOD STOVE BURNING STATUS IS: NO BURNING
UNLESS REGISTERED IN FRESNO... KERN... KINGS... MADERA... MERCED
AND TULARE COUNTIES.
FURTHER INFORMATION IS AVAILABLE AT VALLEYAIR.ORG
&&
.CERTAINTY...
THE LEVEL OF CERTAINTY FOR DAYS 1 AND 2 IS MEDIUM.
THE LEVEL OF CERTAINTY FOR DAYS 3 THROUGH 7 IS MEDIUM.
THIS INFORMATION IS PROVIDED AS PART OF A TRIAL PROJECT CONDUCTED
BY THE NATIONAL WEATHER SERVICE SAN JOAQUIN VALLEY - HANFORD.
CERTAINTY LEVELS INCLUDE LOW...MEDIUM...AND HIGH. PLEASE VISIT
WWW.WEATHER.GOV/HNX/CERTAINTY.PHP /ALL LOWER CASE/ FOR ADDITIONAL
INFORMATION AND/OR TO PROVIDE FEEDBACK.
&&
.CLIMATE...
RECORDS
SITE DATE HI_MAX:YEAR LO_MAX:YEAR HI_MIN:YEAR LO_MIN:YEAR
KFAT 02-19 79:1977 47:1897 55:1996 28:1953
KFAT 02-20 80:1896 45:1909 56:1968 28:1953
KFAT 02-21 77:1991 46:1959 56:1901 26:1953
KBFL 02-19 85:1977 52:1969 54:1996 28:1953
KBFL 02-20 81:1977 52:1922 57:1968 26:1906
KBFL 02-21 82:1991 54:1975 54:2005 27:1893
&&
.HNX WATCHES/WARNINGS/ADVISORIES...
DENSE FOG ADVISORY UNTIL 10 AM PST FRIDAY CAZ089>092.
&&
$$
PUBLIC...RILEY
AVN/FW...BEAN
PREV DISCUSSION...RILEY
SYNOPSIS...RILEY
WEATHER.GOV/HANFORD
AREA FORECAST DISCUSSION
NWS DENVER/BOULDER CO
328 AM MST FRI FEB 20 2015
.SHORT TERM...(TODAY THROUGH TONIGHT )
ISSUED AT 325 AM MST FRI FEB 20 2015
A DISTURBANCE IN NW FLOW ALOFT WILL MOVE ACROSS THE AREA THIS AFTN
WITH DECENT MID LVL QG ASCENT AND STEEP LAPSE RATES. SNOW WILL
INCREASE IN THE MTNS BY MIDDAY WITH A GOOD CHC OF RAIN SHOWERS BY
AFTN OVER THE PLAINS. WITH RATHER UNSTABLE AIRMASS COULD SEE SOME
THUNDER AS WELL.
FOR TONIGHT THE FIRST DISTURBANCE WILL MOVE EAST OF THE AREA WITH
MID LVL DESCENT THRU THE EVENING HOURS SO MAY SEE A DECREASE IN PCPN
ACTIVITY. HOWEVER ANOTHER FEATURE WILL MOVE INTO THE AREA AFTER
MIDNIGHT ALONG WITH A DECENT SHOT OF MID LVL ASCENT AND FAVORABLE
LAPSE RATES. THUS WOULD EXPECT SNOW TO INCREASE IN THE MTNS. OVER
NERN CO A CDFNT WILL MOVE SOUTHWARD ACROSS THE PLAINS THIS EVENING
WHICH BRIEFLY ENHANCE UPSLOPE FLOW BY MIDNIGHT. ONE WOULD THINK
THERE SHOULD BE SOME INCREASE IN PCPN OVERNIGHT OVER PORTIONS OF
NERN CO AND THE FOOTHILLS AS THE NEXT WAVE AND SHOT OF QG ASCENT
MOVES ACROSS. HOWEVER NEITHER THE NAM OR GFS SHOW A LOT OF QPF WITH
AMOUNTS A QUARTER INCH OR LESS OVER NERN CO. SREF PLUME GUIDANCE
ALSO IS ALSO UNDER A QUARTER OR AN INCH SO IF THIS IS THE CASE SNOW
AMOUNTS WOULD MAINLY BE IN THE 1 TO 3 INCH RANGE WITH SLIGHTLY
HIGHER AMOUNTS POSSIBLE IN THE FOOTHILLS.
AT THIS POINT CONFIDENCE OF ISSUING A WARNING FOR THE FOOTHILLS AND
ADJACENT PLAINS FOR TONIGHT IS NOT HIGH SINCE IT APPEARS BEST CHC OF
SNOW MAY NOT OCCUR UNTIL MIDNIGHT OR LATER SO WILL DEFER DECISION TO
DAY SHIFT AND DELAY ONSET OF WATCH. IN THE MTNS WILL START A
WARNING BY EARLY AFTN AND KEEP A WATCH IN PLACE FOR ZNS 30 AND 32.
MEANWHILE BEST CHC OF SNOW FOR ZN 37 LOOKS TO BE ON SAT SO WILL
DEFER WATCH TO 12Z SAT.
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 325 AM MST FRI FEB 20 2015
WINTER WEATHER TO MAKE A STRONG COMEBACK THIS WEEKEND WITH COLDER
TEMPERATURES AND SIGNIFICANT SNOWFALL EXPECTED FOR PORTIONS OF
CWA. APPEARS THE BEST POTENTIAL FOR THE HEAVIEST AND MOST
WIDESPREAD SNOWFALL WILL BE ON SATURDAY AFTERNOON AND SATURDAY
NIGHT. EXPECT INCREASING QG ASCENT SATURDAY MORNING AS BROAD LOW
PRESSURE CONTINUES TO DEVELOP AND BECOME MORE ELONGATED OVER THE
GREAT BASIN. A REINFORCING SHOT OF COLDER AIR MOVES IN SATURDAY
NIGHT WITH ENHANCED UPSLOPE FLOW TO GO ALONG WITH THE VERTICAL
ASCENT AND STEEP LAPSE RATES. THE TROF DEVELOPS INTO A CLOSED LOW
WAY WEST OVER CALIFORNIA ON SUNDAY WITH A RESULTANT STRONG
WESTERLY FLOW ALOFT AND A STRONG JET ALOFT WHICH SHIFTS NORTH
ACROSS EASTERN COLORADO SATURDAY NIGHT AND SUNDAY. THIS COULD
INCREASE CHANCES OF HEAVIER BANDED SNOWFALL. HOWEVER THE LOW LEVEL
FLOW SHIFTS TO THE SOUTHEAST WHICH WOULD BE MORE DOWNSLOPE FLOW
OVER MUCH OF NORTHEAST COLORADO. EXPECT THE HEAVIER SNOWFALL TO BE
MORE LOCALIZED WITH THE JET AND OVER ENHANCED TERRAIN THAT FAVORS
SOUTHEAST FLOW.
AS FOR THE WINTER STORM WATCH...HAVE OPTED TO KEEP IT IN PLACE AND
BACK OFF ON THE ENDING OF THE WATCH. FOR NOW HAVE REMOVED THE
WATCH FROM SUNDAY NIGHT AND MONDAY AM GIVEN THE LONGEVITY OF THE
WATCH PERIOD. CERTAINLY THERE COULD BE SOME SNOW IN THOSE
PERIODS BUT WOULD PREFER TO KEEP THE WATCH WITH TIME PERIOD OF THE
MOST SIGNIFICANT POTENTIAL SNOWFALL. HAVE ALSO DELAYED THE WATCH
UNTIL SATURDAY AFTERNOON OVER THE FAR EASTERN PLAINS/PALMER DIVIDE
WITH THE NEXT WAVE APPROACHING. MODELS CONTINUE TO FOCUS THE
HEAVIEST SNOW OVER THE FRONT RANGE FOOTHILLS AND STRETCHING SOUTH
AND EAST THROUGH THE PALMER DIVIDE.
THE SNOW WILL CONTINUE TO DIMINISH LATE SUNDAY NIGHT AND MONDAY AS
THERE IS WEAK RIDGING THAT DEVELOPS OVER COLORADO FROM THE LOW
PRESSURE OVER CALIFORNIA. SLOW MODERATION IN TEMPERATURES THROUGH
THE MIDDLE OF NEXT WEEK AS THERE WILL BE QUITE A BIT OF SNOW ON
THE GROUND. NEXT STORM SYSTEM MOVES IN WEDNESDAY NIGHT AND
THURSDAY WITH NEXT CHANCE OF SNOW AND COLDER TEMPERATURES. STORM
TOTALS THROUGH THIS WEEKEND LOOK TO BE AROUND 7 TO 14 INCHES WITH
HIGHER AMOUNTS IN THE FOOTHILLS AND PALMER DIVIDE. LESSER AMOUNTS
OVER THE FAR NORTHEAST PLAINS.
&&
.AVIATION...(FOR THE TAFS THROUGH 12Z SATURDAY MORNING)
ISSUED AT 325 AM MST FRI FEB 20 2015
A WEAK BNDRY HAS MOVED ACROSS THE AIRPORT EARLY THIS MORNING WITH
NNE WINDS. HRRR SHOWS WINDS MAINLY VARIABLE THRU MID MORNING AND
THEN BECOMING LIGHT SLY BY 16Z. IN THE AFTN EXPECT A BAND OF
SHOWERS TO MOVE ACROSS WHICH MAY BE ACCOMPANIED BY GUSTY NWLY
OUTFLOW WINDS FOR AN HOUR OR SO. IN ADDITION WITH DECENT LAPSE
RATES IN PLACE CAN`T RULE OUT SOME THUNDER AS WELL. BY EARLY
EVENING A CDNFT WILL MOVE ACROSS THE AREA BY 02Z 03Z WITH GUSTY NLY
WINDS FOR A FEW HOURS. SHOULD SEE SNOW GRADUALLY DVLP BY 06Z WITH
A CONTINUATION THRU 12Z. FOR NOW WILL KEEP AMOUNTS IN THE 1 TO 2
INCH RANGE. HEAVIER SNOWFALL WILL BE POSSIBLE SAT AFTN INTO SAT
NIGHT.
&&
.BOU WATCHES/WARNINGS/ADVISORIES...
WINTER STORM WATCH FROM LATE TONIGHT THROUGH SUNDAY AFTERNOON
FOR COZ037.
WINTER STORM WATCH FROM THIS EVENING THROUGH SUNDAY AFTERNOON
FOR COZ035-036-038>045-049.
WINTER STORM WARNING FROM 2 PM THIS AFTERNOON TO 11 AM MST
SUNDAY FOR COZ031-033-034.
WINTER STORM WATCH FROM THIS AFTERNOON THROUGH SUNDAY MORNING
FOR COZ030-032.
WINTER STORM WATCH FROM SATURDAY MORNING THROUGH SUNDAY
AFTERNOON FOR COZ046-047.
&&
$$
SHORT TERM...RPK
LONG TERM...ENTREKIN
AVIATION...RPK
AREA FORECAST DISCUSSION
NWS ALBANY NY
956 PM EST SAT FEB 21 2015
.SYNOPSIS...
.A LOW PRESSURE SYSTEM WILL MOVE ACROSS THE
REGION TONIGHT...BRINGING A WIDESPREAD LIGHT TO MODERATE SNOWFALL TO
THE AREA. SLEET MAY MIX IN WITH THE SNOW...BUT MAINLY IN AREAS
WELL SOUTH AND EAST OF THE CAPITAL REGION. THE SNOW WILL TAPER TO
SCATTERED SNOW OR RAIN SHOWERS ON SUNDAY. HIGH PRESSURE BUILDS INTO
THE REGION SUNDAY NIGHT THROUGH MONDAY NIGHT...AND THEN MOVES
OFFSHORE TUESDAY.
&&
.NEAR TERM /UNTIL 6 AM SUNDAY MORNING/...
...UPGRADED FULTON...MONTGOMERY AND NRN SARATOGA COUNTIES TO A
WINTER STORM WARNING UNTIL 10 AM SUNDAY...
WINTER WEATHER ADVISORIES CONTINUE FOR THE REST OF THE REGION
THROUGH 10 AM SUNDAY...
AS OF 955 PM EST...INVERTED SFC TROUGHS AHEAD OF CYCLONES IN SW
FLOW ALOFT CONTINUE TO BE TRICKY FOR SNOW FCSTS IN THE ALY FCST
AREA. LOW PRESSURE CONTINUES TO APPROACH WRN NY THIS HOUR.
A HOLE IN THE PCPN HAS REDUCED SNOW TALLIES SO FAR IN THE
IMMEDIATE CAPITAL REGION 2 INCHES OR LESS...BUT AN INTENSE
SNOWBAND WITH RATES OF 1 TO 2 INCHES AN HOUR OVER EARLIER OVER THE
W-CNTRL MOHAWK VALLEY AND PORTIONS OF THE SARATOGA REGION HAS
BOOSTED OUR CONFIDENCE FOR A SHORT-FUSE WINTER STORM WARNING FOR
6-10 INCH SNOW AMOUNTS. REPORTS OF 7 INCHES OR SO HAVE COME IN
FROM FULTON CTY...NRN SARATOGA...AND EXTREME SRN WARREN
COUNTIES...AND WE SUSPECT WIDESPREAD TOTALS IN THE 6-8 INCH RANGE
MAY CONTINUE COMING IN FROM ERN FULTON/MONTGOMERY AND NRN SARATOGA
COUNTIES. JUST OUTSIDE OF THE SMALL WARNING AREA EXPECT SOME 5 TO
8 INCH AMOUNTS. IF THESE BECOME MORE NUMEROUS...THEN WE MAY HAVE
TO EXPAND THE WARNING MORE INTO WARREN/WASHINGTON COUNTIES. AT
THIS TIME WE WILL HOLD WITH THE WARNING AND ADVISORY SET-UP.
THE BACK EDGE OF THE SNOWFALL IS STARTING TO MOVE SOUTH OF THE SRN
DACKS /NRN HERKIMER AND HAMILTON COUNTIES/. THE NEXT UPDATE MAY
START TO DROP SOME OF THE ADVISORY.
AS THE LATEST NAM AND HRRR INDICATED THE SNOW FILLED IN FURTHER
SOUTH AND EAST OF THE MOHAWK VALLEY...AND EXPECT SOME MODERATE
SNOW FOR A FEW HOURS NEAR THE CAPITAL REGION....AND NRN AND ERN
CATSKILLS. WE SLIGHTLY REDUCED TOTALS OVER THE ERN CATSKILLS TO
3-6 INCHES. WE LOWERED AMOUNTS SOME IN THE IMMEDIATE CAPITAL
REGION...MID HUDSON VALLEY TO 2 TO 6 INCHES. MANY LOCATIONS MAY BE
CLOSER TO THE LOWER END OF THE RANGE DUE TO THE DRY SLOT THAT SHUT
SNOW DOWN EARLIER.
THERE IS SOME FGEN WITH THIS SYSTEM AT H850-700 LEVEL WHICH
ENHANCED THE SNOWFALL TONIGHT JUST NORTH AND WEST OF THE CAPITAL
REGION. THE BULK OF THE SNOWFALL SHOULD OCCUR BETWEEN NOW AND 2 AM
SUNDAY. THE SNOW TAPERS OFF TO SCATTERED SNOW SHOWERS BEFORE
DAYBREAK.
SNOWFALL TOTALS GENERALLY 2-6 INCHES EXCEPT NORTH AND WEST OF THE
CAPITAL REGION MAY RECEIVE 4 TO 8 INCHES...WITH A SWATHE OF 6 TO
10 INCHES IN THE CENTRAL MOHAWK VALLEY...NRN SARATOGA REGION...AND
PERHAPS INTO THE LOWER REACHES OF THE LAKE GEORGE AREA.
&&
.SHORT TERM /6 AM SUNDAY MORNING THROUGH TUESDAY/...
ON SUNDAY THERE MAY BE A FEW LINGERING RAIN OR SNOW SHOWERS
OTHERWISE EXPECT AT LEAST PARTIAL CLEARING BY AFTERNOON. HIGHS
WILL BE CLOSER TO NORMAL FOR THIS TIME OF YEAR WITH READINGS IN
THE UPPER 20S TO UPPER 30S.
IN THE WAKE OF AN ARCTIC COLD FRONT...BITTERLY COLD AIR RETURNS TO
THE REGION SUNDAY NIGHT THROUGH TUESDAY WITH DANGEROUS WIND CHILL
VALUES ONCE AGAIN. THIS WILL BE HIGHLIGHTED IN THE HWO. LOWS
SUNDAY NIGHT ARE EXPECTED TO BE IN THE 10 BELOW ZERO TO 10 ABOVE
ZERO RANGE. HIGHS ON MONDAY ARE EXPECTED TO RECOVER LITTLE WITH
READINGS IN THE 5 BELOW TO 15 ABOVE ZERO RANGE. LOWS MONDAY NIGHT
ARE EXPECTED TO BE IN THE 20 BELOW TO 5 BELOW ZERO RANGE WITH
HIGHS ON TUESDAY IN THE TEENS. LATER ON TUESDAY MAINLY DURING THE
AFTERNOON THERE WILL BE A CHANCE OF SNOW SHOWERS ACROSS THE
NORTHWEST HALF OF THE FA AS A CLIPPER TYPE SYSTEM TRACKS ACROSS
SOUTHERN CANADA.
&&
.LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/...
AS HAS BEEN THE TREND OVER THE PAST MONTH OR SO...BELOW NORMAL
TEMPERATURES WILL CONTINUE IN THE EXTENDED PORTION OF THE FORECAST
INTO NEXT WEEKEND WITH A MEAN LONGWAVE TROUGH OVER THE NRN TIER OF
THE CONUS INTO THE NORTHEAST. A SOUTHERN STREAM SYSTEM MAY IMPACT
NY AND NEW ENGLAND NEXT WEEKEND BASED ON THE MEDIUM RANGE
GUIDANCE/ENSEMBLES.
TUESDAY NIGHT INTO WEDNESDAY...IN THE NW FLOW ALOFT...A SHORT-WAVE
WILL APPROACH THE REGION. SOME WARM ADVECTION AHEAD OF THE CLIPPER
TYPE LOW MOVING ACROSS E/SE ONTARIO WILL FOCUS A CHC OF SNOW SHOWERS
OR LIGHT SNOW. THE SYNOPTIC FORCING DOESN/T LOOK SPECTACULAR...BUT
A FEW INCHES OF LIGHT SNOW WILL BE POSSIBLE. BY WEDNESDAY
AFTERNOON...THE CLIPPER MOVES ACROSS SRN QUEBEC TOWARDS THE GULF OF
ST LAWRENCE. A COLD FRONT MOVES THROUGH THE FCST AREA WITH A CHC OF
SNOW SHOWERS...AND ANOTHER SURGE OF ARCTIC AIR. LOWS WILL RANGE
FROM 5-10 DEGS OVER THE HILLS AND MTNS...AND UPPER SINGLE NUMBERS TO
MID TEENS IN THE VALLEYS. HIGHS ON WED PRIOR TO THE FRONTAL PASSAGE
WILL REACH THE M20S TO L30S IN THE VALLEYS AND OVER THE HILLS...AND
UPPERS TEENS TO M20S OVER THE MTNS.
WED NIGHT...ARCTIC AIR INFILTRATES THE FCST AREA ONCE AGAIN WITH 925
HPA TEMPS TUMBLING TO -15C TO -25C OVER THE FCST AREA. THERE IS A
SLIGHT CHC TO CHC OF SOME LAKE EFFECT AND WESTERLY UPSLOPE SNOW
SHOWERS IN THE WRN DACKS...THE NRN TACONICS...AND SRN GREENS. LIGHT
SNOW ACCUMS WILL BE POSSIBLE. LOWS WILL BE VERY COLD AGAIN WITH
TEMPS ZERO TO 5 ABOVE OR SO FROM THE CAPITAL DISTRICT SOUTH AND
EAST...AND ZERO TO 10 BELOW NORTH AND WEST AND OVER THE SRN GREENS.
WIND CHILLS MAY GET CLOSE TO ADVISORY LEVELS OVER THE SRN DACKS AND
ERN CATSKILLS.
THU INTO SAT...ARCTIC HIGH PRESSURE INITIALLY OVER THE NRN PLAINS
WILL RIDGE EASTWARD TOWARDS THE NORTHEAST. A STRETCH OF FAIR BUT
VERY COLD WX IS EXPECTED INTO THE FIRST HALF OF THE WEEKEND. THE
SFC ANTICYCLONE MOVES OVER THE MIDWEST AND CNTRL MS RIVER VALLEY
FRIDAY MORNING...THEN SETTLES OVER PA AND NY BY SATURDAY MORNING.
HIGH TEMPS ON THU WILL ONLY BE IN THE SINGLE NUMBERS OVER THE
MTNS...AND TEENS OVER THE REST OF THE FCST AREA. LOWS THU NIGHT
WILL PLUMMET WITH NEAR IDEAL RADIATIONAL COOLING CONDITIONS WITH
ZERO TO 5 BELOW ZERO READINGS FROM THE CAPITAL REGION SOUTH AND
EAST...AND 5 BELOW TO 15 BELOW NORTH AND WEST. TEMPS SLIGHTLY
MODIFY ON FRIDAY WITH TEENS TO L20S...AND ANOTHER COLD NIGHT SIMILAR
TO THU NIGHT IS EXPECTED FOR FRI NIGHT/SATURDAY MORNING. A
DISTURBANCE HEADING OUT OF THE SRN PLAINS ASSOCIATED WITH THE SRN
STREAM/SUBTROPICAL JET MOVES N/NE ON SATURDAY. SOME CLOUDS WILL
INCREASE DURING THE DAY WITH SOME LIGHT SNOW GETTING CLOSES TO THE
MID HUDSON VALLEY/NW CT LATE IN THE DAY...THOUGH THERE ARE SOME
TIMING DIFFERENCES AND STORM TRACK DISPARITIES WITH THE
GFS...ECMWF...AND ENSEMBLES FOR SAT NIGHT INTO SUNDAY. MOST OF
SATURDAY SHOULD BE COLD AND DRY...AS THE 2ND HALF OF THE WEEKEND
LOOKS POTENTIALLY UNSETTLED.
&&
.AVIATION /03Z SUNDAY THROUGH THURSDAY/...
LOW PRESSURE CONTINUES TO APPROACH FROM OHIO TONIGHT. SNOWFALL
CONTINUES AHEAD OF THE CYCLONE. THE COLD FRONT TO THE SYSTEM MOVES
EAST OF THE REGION TOMORROW AFTERNOON. A SECONDARY COLD FRONT WITH
A SURGE OF ARCTIC AIR WILL MOVE THROUGH TOMORROW NIGHT.
WIDESPREAD MVFR/LOW MVFR CONDITIONS CONTINUE ACROSS E-CNTRL NY AND
WRN NEW ENGLAND WITH SOME REDUCTIONS TO IFR LEVELS AT TIMES IN THE
SNOW. A LULL IN THE PCPN HAS OCCURRED FROM KALB-KPSF SOUTH AND
WEST...BUT THE SNOW SHOULD FILL BACK IN PRIOR TO 03Z. EXPECT
WIDESPREAD MVFR/IFR CONDITIONS TO CONTINUE PRIOR TO 06Z. THE SNOW
SHOULD GRADUALLY TAPER OFF FROM NW TO SE BTWN 06Z-12Z. EXPECT CIGS
AND VSBYS TO RISE TO HIGH MVFR/LOW VFR LEVELS BTWN 10Z-14Z. VFR
CONDITIONS ARE EXPECTED FOR MOST OF SUNDAY AFTERNOON.
THE WINDS WILL SOUTHERLY AT 8 TO 15 KTS...WITH GUSTS OF 20 TO 25
KTS AT KALB/KPSF. THE WINDS WILL SUBSIDE AFTER MIDNIGHT TO 7 KTS
OR LESS...THEN SHIFT TO THE WEST TO SOUTHWEST AT 10 KTS OR LESS
AROUND OR SHORTLY AFTER SUNRISE ON SUNDAY. EXPECT W TO NW WINDS OF
5-12 KTS AFTER 17Z/SUN.
OUTLOOK...
SUN NIGHT: LOW OPERATIONAL IMPACT. BRISK WINDS.
MON-TUE: NO OPERATIONAL IMPACT. NO SIG WX.
TUE NIGHT-WED: MODERATE OPERATIONAL IMPACT. CHC SHSN.
THU: NO OPERATIONAL IMPACT. NO SIG WX.
&&
.HYDROLOGY...
ICE WILL CONTINUE TO THICKEN ON AREA RIVERS...STREAMS...LAKES...AND
PONDS...AS CONTINUED BELOW NORMAL TEMPERATURES REMAIN IN PLACE
THROUGH MOST OF THE NEXT 7 DAYS. TEMPERATURES MAY BRIEFLY RISE
ABOVE FREEZING SUNDAY BEFORE RETURNING TO VERY COLD LEVELS ONCE
AGAIN FOR NEXT WEEK.
3-8 INCHES OF SNOW IS EXPECTED THROUGH TONIGHT...TAPERING OFF
TO LIGHT SHOWERS OF RAIN OR SNOW SUNDAY. ANY RAIN WILL HAVE NO
IMPACT ON THE SNOWPACK.
THEN...IT TURNS EXTREMELY COLD AGAIN MONDAY THROUGH MUCH OF NEXT
WEEK.
FOR DETAILS ON SPECIFIC AREA RIVERS AND LAKES...INCLUDING
OBSERVED AND FORECAST RIVER STAGES AND LAKE ELEVATIONS...PLEASE
VISIT THE ADVANCED HYDROLOGIC PREDICTION SERVICE /AHPS/ GRAPHS ON
OUR WEBSITE.
&&
.ALY WATCHES/WARNINGS/ADVISORIES...
CT...WINTER WEATHER ADVISORY UNTIL 10 AM EST SUNDAY FOR CTZ001-013.
NY...WINTER WEATHER ADVISORY UNTIL 10 AM EST SUNDAY FOR NYZ032-033-
038-042-043-047>054-058>061-063>066-083-084.
WINTER STORM WARNING UNTIL 10 AM EST SUNDAY FOR NYZ039>041-082.
MA...WINTER WEATHER ADVISORY UNTIL 10 AM EST SUNDAY FOR MAZ001-025.
VT...WINTER WEATHER ADVISORY UNTIL 10 AM EST SUNDAY FOR VTZ013>015.
&&
$$
SYNOPSIS...11/WASULA
NEAR TERM...WASULA
SHORT TERM...11
LONG TERM...WASULA
AVIATION...WASULA
HYDROLOGY...11
AREA FORECAST DISCUSSION
NWS ALBANY NY
825 PM EST SAT FEB 21 2015
.SYNOPSIS...
.A LOW PRESSURE SYSTEM WILL MOVE ACROSS THE
REGION TONIGHT...BRINGING A WIDESPREAD LIGHT TO MODERATE SNOWFALL TO
THE AREA. SLEET MAY MIX IN WITH THE SNOW...BUT MAINLY IN AREAS
WELL SOUTH AND EAST OF THE CAPITAL REGION. THE SNOW WILL TAPER TO
SCATTERED SNOW OR RAIN SHOWERS ON SUNDAY. HIGH PRESSURE BUILDS INTO
THE REGION SUNDAY NIGHT THROUGH MONDAY NIGHT...AND THEN MOVES
OFFSHORE TUESDAY.
&&
.NEAR TERM /UNTIL 6 AM SUNDAY MORNING/...
...UPGRADED FULTON...MONTGOMERY AND NRN SARATOGA COUNTIES TO A
WINTER STORM WARNING UNTIL 10 AM SUNDAY...
WINTER WEATHER ADVISORIES CONTINUE FOR THE REST OF THE REGION
THROUGH 10 AM SUNDAY...
AS OF 825 PM EST...INVERTED SFC TROUGHS AHEAD OF CYCLONES IN SW
FLOW ALOFT CONTINUE TO BE TRICKY FOR SNOW FCSTS IN THE ALY FCST
AREA. A HOLE IN THE PCPN HAS REDUCED SNOW TALLIES SO FAR IN THE
IMMEDIATE CAPITAL REGION TO AN INCH OR LESS...BUT AN INTENSE
SNOWBAND WITH RATES OF 1 TO 2 INCHES AN HOUR OVER THE W-CNTRL
MOHAWK VALLEY AND PORTIONS OF THE SARATOGA REGION HAS BOOSTED OUR
CONFIDENCE FOR A SHORT-FUSE WINTER STORM WARNING FOR 6-10 INCH
SNOW AMOUNTS. A REPORT OF 7 INCHES HAS COME IN FROM BLEECKER IN
FULTON CTY...AND WE SUSPECT WIDESPREAD TOTALS IN THE 6-8 INCH
RANGE MAY CONTINUE COMING IN FROM ERN FULTON/MONTGOMERY AND NRN
SARATOGA COUNTIES. JUST OUTSIDE OF THE SMALL WARNING AREA EXPECT
SOME 5 TO 8 INCH AMOUNTS. IF THESE BECOME MORE NUMEROUS...THEN WE
MAY HAVE TO EXPAND THE WARNING MORE INTO WARREN/WASHINGTON
COUNTIES.
AS THE LATEST NAM AND HRRR INDICATED THE SNOW IS STARTING TO FILL
IN FURTHER SOUTH AND EAST...AND WE EXPECT SOME MODERATE SNOW TO
START BACK UP OVER THE CAPITAL REGION....AND NRN AND ERN
CATSKILLS. WE SLIGHTLY REDUCED TOTALS OVER THE ERN CATSKILLS TO
3-6 INCHES. WE LOWERED AMOUNTS SOME IN THE IMMEDIATE CAPITAL
REGION...MID HUDSON VALLEY TO 2 TO 6 INCHES. MANY LOCATIONS MAY BE
CLOSER TO THE LOWER END OF THE RANGE DUE TO THE DRY SLOT THAT SHUT
SNOW DOWN EARLIER.
THERE IS SOME FGEN WITH THIS SYSTEM AT H850-700 LEVEL WHICH
ENHANCED THE SNOWFALL TONIGHT JUST NORTH AND WEST OF THE CAPITAL
REGION. THE BULK OF THE SNOWFALL SHOULD OCCUR BETWEEN NOW AND 2 AM
SUNDAY. THE SNOW TAPERS OFF TO SCATTERED SNOW SHOWERS BEFORE
DAYBREAK.
SNOWFALL TOTALS GENERALLY 2-6 INCHES EXCEPT NORTH AND WEST OF THE
CAPITAL REGION MAY RECEIVE 4 TO 8 INCHES...WITH A SWATHE OF 6 TO
10 INCHES IN THE CENTRAL MOHAWK VALLEY...NRN SARATOGA REGION...AND
PERHAPS INTO THE LOWER REACHES OF THE LAKE GEORGE AREA.
&&
.SHORT TERM /6 AM SUNDAY MORNING THROUGH TUESDAY/...
ON SUNDAY THERE MAY BE A FEW LINGERING RAIN OR SNOW SHOWERS
OTHERWISE EXPECT AT LEAST PARTIAL CLEARING BY AFTERNOON. HIGHS
WILL BE CLOSER TO NORMAL FOR THIS TIME OF YEAR WITH READINGS IN
THE UPPER 20S TO UPPER 30S.
IN THE WAKE OF AN ARCTIC COLD FRONT...BITTERLY COLD AIR RETURNS TO
THE REGION SUNDAY NIGHT THROUGH TUESDAY WITH DANGEROUS WIND CHILL
VALUES ONCE AGAIN. THIS WILL BE HIGHLIGHTED IN THE HWO. LOWS
SUNDAY NIGHT ARE EXPECTED TO BE IN THE 10 BELOW ZERO TO 10 ABOVE
ZERO RANGE. HIGHS ON MONDAY ARE EXPECTED TO RECOVER LITTLE WITH
READINGS IN THE 5 BELOW TO 15 ABOVE ZERO RANGE. LOWS MONDAY NIGHT
ARE EXPECTED TO BE IN THE 20 BELOW TO 5 BELOW ZERO RANGE WITH
HIGHS ON TUESDAY IN THE TEENS. LATER ON TUESDAY MAINLY DURING THE
AFTERNOON THERE WILL BE A CHANCE OF SNOW SHOWERS ACROSS THE
NORTHWEST HALF OF THE FA AS A CLIPPER TYPE SYSTEM TRACKS ACROSS
SOUTHERN CANADA.
&&
.LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/...
AS HAS BEEN THE TREND OVER THE PAST MONTH OR SO...BELOW NORMAL
TEMPERATURES WILL CONTINUE IN THE EXTENDED PORTION OF THE FORECAST
INTO NEXT WEEKEND WITH A MEAN LONGWAVE TROUGH OVER THE NRN TIER OF
THE CONUS INTO THE NORTHEAST. A SOUTHERN STREAM SYSTEM MAY IMPACT
NY AND NEW ENGLAND NEXT WEEKEND BASED ON THE MEDIUM RANGE
GUIDANCE/ENSEMBLES.
TUESDAY NIGHT INTO WEDNESDAY...IN THE NW FLOW ALOFT...A SHORT-WAVE
WILL APPROACH THE REGION. SOME WARM ADVECTION AHEAD OF THE CLIPPER
TYPE LOW MOVING ACROSS E/SE ONTARIO WILL FOCUS A CHC OF SNOW SHOWERS
OR LIGHT SNOW. THE SYNOPTIC FORCING DOESN/T LOOK SPECTACULAR...BUT
A FEW INCHES OF LIGHT SNOW WILL BE POSSIBLE. BY WEDNESDAY
AFTERNOON...THE CLIPPER MOVES ACROSS SRN QUEBEC TOWARDS THE GULF OF
ST LAWRENCE. A COLD FRONT MOVES THROUGH THE FCST AREA WITH A CHC OF
SNOW SHOWERS...AND ANOTHER SURGE OF ARCTIC AIR. LOWS WILL RANGE
FROM 5-10 DEGS OVER THE HILLS AND MTNS...AND UPPER SINGLE NUMBERS TO
MID TEENS IN THE VALLEYS. HIGHS ON WED PRIOR TO THE FRONTAL PASSAGE
WILL REACH THE M20S TO L30S IN THE VALLEYS AND OVER THE HILLS...AND
UPPERS TEENS TO M20S OVER THE MTNS.
WED NIGHT...ARCTIC AIR INFILTRATES THE FCST AREA ONCE AGAIN WITH 925
HPA TEMPS TUMBLING TO -15C TO -25C OVER THE FCST AREA. THERE IS A
SLIGHT CHC TO CHC OF SOME LAKE EFFECT AND WESTERLY UPSLOPE SNOW
SHOWERS IN THE WRN DACKS...THE NRN TACONICS...AND SRN GREENS. LIGHT
SNOW ACCUMS WILL BE POSSIBLE. LOWS WILL BE VERY COLD AGAIN WITH
TEMPS ZERO TO 5 ABOVE OR SO FROM THE CAPITAL DISTRICT SOUTH AND
EAST...AND ZERO TO 10 BELOW NORTH AND WEST AND OVER THE SRN GREENS.
WIND CHILLS MAY GET CLOSE TO ADVISORY LEVELS OVER THE SRN DACKS AND
ERN CATSKILLS.
THU INTO SAT...ARCTIC HIGH PRESSURE INITIALLY OVER THE NRN PLAINS
WILL RIDGE EASTWARD TOWARDS THE NORTHEAST. A STRETCH OF FAIR BUT
VERY COLD WX IS EXPECTED INTO THE FIRST HALF OF THE WEEKEND. THE
SFC ANTICYCLONE MOVES OVER THE MIDWEST AND CNTRL MS RIVER VALLEY
FRIDAY MORNING...THEN SETTLES OVER PA AND NY BY SATURDAY MORNING.
HIGH TEMPS ON THU WILL ONLY BE IN THE SINGLE NUMBERS OVER THE
MTNS...AND TEENS OVER THE REST OF THE FCST AREA. LOWS THU NIGHT
WILL PLUMMET WITH NEAR IDEAL RADIATIONAL COOLING CONDITIONS WITH
ZERO TO 5 BELOW ZERO READINGS FROM THE CAPITAL REGION SOUTH AND
EAST...AND 5 BELOW TO 15 BELOW NORTH AND WEST. TEMPS SLIGHTLY
MODIFY ON FRIDAY WITH TEENS TO L20S...AND ANOTHER COLD NIGHT SIMILAR
TO THU NIGHT IS EXPECTED FOR FRI NIGHT/SATURDAY MORNING. A
DISTURBANCE HEADING OUT OF THE SRN PLAINS ASSOCIATED WITH THE SRN
STREAM/SUBTROPICAL JET MOVES N/NE ON SATURDAY. SOME CLOUDS WILL
INCREASE DURING THE DAY WITH SOME LIGHT SNOW GETTING CLOSES TO THE
MID HUDSON VALLEY/NW CT LATE IN THE DAY...THOUGH THERE ARE SOME
TIMING DIFFERENCES AND STORM TRACK DISPARITIES WITH THE
GFS...ECMWF...AND ENSEMBLES FOR SAT NIGHT INTO SUNDAY. MOST OF
SATURDAY SHOULD BE COLD AND DRY...AS THE 2ND HALF OF THE WEEKEND
LOOKS POTENTIALLY UNSETTLED.
&&
.AVIATION /01Z SUNDAY THROUGH THURSDAY/...
LOW PRESSURE CONTINUES TO APPROACH FROM OHIO TONIGHT. SNOWFALL
CONTINUES AHEAD OF THE CYCLONE. THE COLD FRONT TO THE SYSTEM MOVES
EAST OF THE REGION TOMORROW AFTERNOON. A SECONDARY COLD FRONT WITH
A SURGE OF ARCTIC AIR WILL MOVE THROUGH TOMORROW NIGHT.
WIDESPREAD MVFR/LOW MVFR CONDITIONS CONTINUE ACROSS E-CNTRL NY AND
WRN NEW ENGLAND WITH SOME REDUCTIONS TO IFR LEVELS AT TIMES IN THE
SNOW. A LULL IN THE PCPN HAS OCCURRED FROM KALB-KPSF SOUTH AND
WEST...BUT THE SNOW SHOULD FILL BACK IN PRIOR TO 03Z. EXPECT
WIDESPREAD MVFR/IFR CONDITIONS TO CONTINUE PRIOR TO 06Z. THE SNOW
SHOULD GRADUALLY TAPER OFF FROM NW TO SE BTWN 06Z-12Z. EXPECT CIGS
AND VSBYS TO RISE TO HIGH MVFR/LOW VFR LEVELS BTWN 10Z-14Z. VFR
CONDITIONS ARE EXPECTED FOR MOST OF SUNDAY AFTERNOON.
THE WINDS WILL SOUTHERLY AT 8 TO 15 KTS...WITH GUSTS OF 20 TO 25
KTS AT KALB/KPSF. THE WINDS WILL SUBSIDE AFTER MIDNIGHT TO 7 KTS
OR LESS...THEN SHIFT TO THE WEST TO SOUTHWEST AT 10 KTS OR LESS
AROUND OR SHORTLY AFTER SUNRISE ON SUNDAY. EXPECT W TO NW WINDS OF
5-12 KTS AFTER 17Z/SUN.
OUTLOOK...
SUN NIGHT: LOW OPERATIONAL IMPACT. BRISK WINDS.
MON-TUE: NO OPERATIONAL IMPACT. NO SIG WX.
TUE NIGHT-WED: MODERATE OPERATIONAL IMPACT. CHC SHSN.
THU: NO OPERATIONAL IMPACT. NO SIG WX.
&&
.HYDROLOGY...
ICE WILL CONTINUE TO THICKEN ON AREA RIVERS...STREAMS...LAKES...AND
PONDS...AS CONTINUED BELOW NORMAL TEMPERATURES REMAIN IN PLACE
THROUGH MOST OF THE NEXT 7 DAYS. TEMPERATURES MAY BRIEFLY RISE
ABOVE FREEZING SUNDAY BEFORE RETURNING TO VERY COLD LEVELS ONCE
AGAIN FOR NEXT WEEK.
3-8 INCHES OF SNOW IS EXPECTED THROUGH TONIGHT...TAPERING OFF
TO LIGHT SHOWERS OF RAIN OR SNOW SUNDAY. ANY RAIN WILL HAVE NO
IMPACT ON THE SNOWPACK.
THEN...IT TURNS EXTREMELY COLD AGAIN MONDAY THROUGH MUCH OF NEXT
WEEK.
FOR DETAILS ON SPECIFIC AREA RIVERS AND LAKES...INCLUDING
OBSERVED AND FORECAST RIVER STAGES AND LAKE ELEVATIONS...PLEASE
VISIT THE ADVANCED HYDROLOGIC PREDICTION SERVICE /AHPS/ GRAPHS ON
OUR WEBSITE.
&&
.ALY WATCHES/WARNINGS/ADVISORIES...
CT...WINTER WEATHER ADVISORY UNTIL 10 AM EST SUNDAY FOR CTZ001-013.
NY...WINTER WEATHER ADVISORY UNTIL 10 AM EST SUNDAY FOR NYZ032-033-
038-042-043-047>054-058>061-063>066-083-084.
WINTER STORM WARNING UNTIL 10 AM EST SUNDAY FOR NYZ039>041-082.
MA...WINTER WEATHER ADVISORY UNTIL 10 AM EST SUNDAY FOR MAZ001-025.
VT...WINTER WEATHER ADVISORY UNTIL 10 AM EST SUNDAY FOR VTZ013>015.
&&
$$
SYNOPSIS...11/WASULA
NEAR TERM...WASULA
SHORT TERM...11
LONG TERM...WASULA
AVIATION...WASULA
HYDROLOGY...11
AREA FORECAST DISCUSSION
NWS TAMPA BAY RUSKIN FL
755 PM EST SAT FEB 21 2015
.UPDATE...
00Z WATER VAPOR AND H4 RAP ANALYSIS SHOW AN UPPER LEVEL PATTERN
CONSISTING OF A DOMINANT LONGWAVE TROUGH OVER MUCH OF THE CONUS.
THIS TROUGH DOES DIG DOWN INTO THE DEEP SOUTH...BUT DOES NOT REACH
THE GULF OF MEXICO LEAVING OUR REGION UNDER A MORE ZONAL FLOW
PATTERN ALOFT...AND THIS ZONAL FLOW WILL PERSIST INTO THE EARLY
PORTION OF THE WEEK.
IN THE LOWER LEVELS...FLORIDA PENINSULA RESIDES WITHIN A SOUTHEAST
TO SOUTH FLOW AROUND A RIDGE OF HIGH PRESSURE EXTENDING
SOUTHWESTWARD ACROSS THE WESTERN ATLANTIC TO THE EASTERN GULF OF
MEXICO. TO OUR NORTH A QUASI-STATIONARY FRONTAL BOUNDARY EXTENDS
FROM THE LOWER MS VALLEY TO THE TN VALLEY AND THEN INTO THE
NORTHEASTERN STATES. THIS FRONT WILL MAKE SOME PROGRESS SOUTHWARD
OVER THE NEXT 24 HOURS...BUT WILL REMAIN TO OUR NORTH ALLOWING OUR
WARMING TREND TO CONTINUE ON SUNDAY.
THE COLD STREAK OF THE PAST FEW DAYS IS EXITING THE REGION AT ALL
LEVELS OF THE ATMOSPHERE...WITH THE 22/00Z KTBW SOUNDING PROFILE
SHOWING SIGNIFICANT WARMING TROUGH MUCH OF THE COLUMN IN THE PAST 24
HOURS. TEMPERATURES THE REMAINDER OF THE OVERNIGHT WILL BE
NOTICEABLY WARMER THAN THE PAST SEVERAL NIGHTS WITH MANY SPOTS NOT
FALLING OUT OF THE 50S. COLDEST LOCATIONS WILL BE UP TOWARD CITRUS
AND LEVY COUNTY WERE UPPER 40S ARE POSSIBLE BY SUNRISE. WE WILL
CONTINUE UNDER A BROAD WAA REGIME OVERNIGHT THAT WILL LIKELY RESULT
IN AREAS OF MID-LEVEL CLOUDS ABOVE GENERALLY 5KFT...BUT THESE CLOUDS
WILL ONLY HELP TO KEEP TEMPERATURES UP FURTHER.
THE WARMING ALOFT AND GOOD DIURNAL MIXING ON SUNDAY WILL HELP PUSH
OUR LOCAL TEMPERATURES WELL INTO THE 70S FOR MANY SPOTS...AND EVEN
SOME LOWER 80S POSSIBLE AWAY FROM THE COAST TO THE SOUTH OF THE I-4
CORRIDOR. THIS GOOD TERRESTRIAL WARMING ALONG WITH A GENERALLY WEAK
GRADIENT AND COOL SHELF WATERS SHOULD FORCE A DEFINED SEA-BREEZE BY
THE MIDDLE AFTERNOON HOURS. LOCAL HIGH RESOLUTION WRF-ARW MODEL
MEMBERS ARE ALL SHOWING THIS SEA-BREEZE FORMATION ALONG THE ENTIRE
FL WEST COAST...WITH A RAPID EXPANSION INLAND AFTER 18-19Z. THE
ONSHORE FLOW OFF THE SHELF WATERS WILL NO DOUBT KEEP TEMPERATURES AT
THE BEACHES DOWN AT LEAST SEVERAL DEGREES FROM LOCATIONS EVEN A FEW
MILES INLAND. THIS TYPE OF STRONGER SEA-BREEZE AND RESULTING COOLER
COASTAL TEMPS DURING THE AFTERNOON HOURS WILL BECOME MORE AND MORE
FREQUENT IN THE COMING COUPLE OF MONTHS.
ENJOY YOUR SATURDAY NIGHT AND TRY TO GET OUT AND ENJOY THE WARMER
SUNDAY TEMPERATURES.
&&
.AVIATION...
VFR CONDITIONS PREVAIL ACROSS WEST CENTRAL AND SOUTHWEST FLORIDA
THIS EVENING UNDER A SCT-BKN MID-LEVEL CLOUD DECK GENERALLY ABOVE
6KFT. SOME BRIEF PERIOD OF MVFR VIS ARE POSSIBLE LATE AT NIGHT FOR
KLAL AND KPGD...HOWEVER NO SIGNIFICANT RESTRICTIONS ARE ANTICIPATED
OVERNIGHT. ANY PATCHY FOG WILL DISSIPATE QUICKLY SUNDAY MORNING WITH
VFR CONDITIONS PREVAILING THROUGH THE REMAINDER OF THE DAYLIGHT
HOURS.
&&
.MARINE...
E/SE WIND FLOW TO CONTINUE OVERNIGHT AS WINDS WILL REMAIN 10 KNOTS
OR LESS WITH SEAS AT 1-2 FEET. THESE PLEASANT BOATING CONDITIONS
WILL CONTINUE THROUGH MID WEEK BEFORE A COLD FRONT STALLS ACROSS THE
NORTHERN HALF OF THE FLORIDA PENINSULA. WINDS AND SEAS WILL SLIGHTLY
INCREASE AT THAT TIME BUT ARE EXPECTED TO REMAIN BELOW CAUTIONARY
LEVELS. NO MAJOR CHANGES NEEDED FOR THE EVENING UPDATE.
&&
.PRELIMINARY POINT TEMPS/POPS...
TPA 57 74 63 72 / 10 0 0 10
FMY 58 80 63 79 / 10 10 10 0
GIF 57 80 63 78 / 10 10 10 10
SRQ 56 74 62 72 / 10 0 0 0
BKV 51 76 58 72 / 0 0 0 10
SPG 60 74 64 72 / 10 0 10 10
&&
.TBW WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
GULF WATERS...NONE.
&&
$$
UPDATE/AVIATION...MROCZKA
MARINE...MCKAUGHAN
AREA FORECAST DISCUSSION
NWS GOODLAND KS
223 PM MST FRI FEB 20 2015
.SHORT TERM...(THIS EVENING THROUGH SATURDAY)
ISSUED AT 220 PM MST FRI FEB 20 2015
VISIBLE SATELLITE IMAGERY WAS INDICATING PARTLY TO MOSTLY CLOUDY
SKIES OVER THE TRI STATE AREA IN THE EARLY AFTERNOON...WITH RADAR
INDICATING SOME LIGHT PRECIPITATION BEGINNING TO OCCUR IN CENTRAL
NEBRASKA AND EASTERN COLORADO AHEAD OF AN UPPER LEVEL SHORTWAVE
TROUGH. WATER VAPOR IMAGERY SHOWED A STEADY STREAM OF MOISTURE THAT
WILL MOVE INTO THE FORECAST AREA TONIGHT...WHICH WILL BRING OVERCAST
SKIES AND CHANCES FOR PRECIPITATION.
HRRR AND RAP FORECASTS SHOW LIGHT RAIN SHOWERS BEGINNING TO AFFECT
EASTERN COLORADO BETWEEN THE 21Z AND 00Z TIME PERIOD TONIGHT...AND
THEN GRADUALLY SPREADING IN COVERAGE OVER NORTHWEST KANSAS. RAIN
WILL TRANSITION TO A RAIN/SNOW MIX AROUND 3Z...AND THEN TURN TO ALL
SNOW AFTER 6Z. PRECIPITATION AREA WILL ENTER A DRY PERIOD SHORTLY
AFTER 6Z AND LAST THROUGH 18Z SATURDAY WHERE VERY LIGHT SNOW
ACCUMULATIONS WILL OCCUR...IF ANY. MODEL GUIDANCE WAS SHOWING
ANYWHERE FROM A HALF INCH UP TO 2 INCHES FOR EASTERN COLORADO
ACCUMULATING DURING THE DAY SATURDAY. THE HIGHER GUIDANCES SEEMED TO
BE ACCUMULATING SNOW BEFORE THE 850 FREEZING LINE PASSED THROUGH AND
THE 1540 LINE FOR THE 850-700 MB THICKNESS...WHICH LED TO THE
DECISION TO BRING SNOW AMOUNTS UNDER HALF AN INCH DURING THE DAY
SATURDAY.
RAIN AND RAIN/SNOW MIXES WILL OCCUR SOUTH OF A LINE FROM CHEYENNE
WELLS COLORADO TO TRENTON NEBRASKA SATURDAY AFTERNOON...WITH SNOW
NORTH OF THIS LINE. ABOUT ANOTHER HALF OF AN INCH WILL ACCUMULATE
FOR EASTERN COLORADO BEFORE 00Z SUNDAY WHERE THE PRECIPITATION WILL
ALL CHANGE OVER TO SNOW...WHICH WILL BRING THE GREATER SNOW
ACCUMULATIONS HEADING INTO SATURDAY NIGHT. WITH A LACK OF LOWER AND
MID LEVEL JET WINDS IN COMBINATION WITH A 8 MB SURFACE PRESSURE
GRADIENT...WINDS ARE NOT EXPECTED TO GUST ABOVE 25 MPH DURING THIS
PERIOD. THEREFORE...BLOWING SNOW WILL NOT BE AN ISSUE.
.LONG TERM...(SATURDAY NIGHT THROUGH FRIDAY)
ISSUED AT 220 PM MST FRI FEB 20 2015
UPPER FLOW WILL BE WESTERLY ACROSS THE CENTRAL PLAINS SATURDAY NIGHT
AS THE BROAD TROUGH ELONGATES FROM THE WEST COAST TO THE GREAT
LAKES. AS THE TROUGH CONTINUES TO SPLIT ON SUNDAY A RIDGE WILL
START AMPLIFYING OVER THE CENTRAL PLAINS. THE RIDGING CONTINUES
OVER THE CENTRAL PLAINS MONDAY WITH A LOW OVER THE DESERT SOUTHWEST
AND THE OTHER PORTION OF THE TROUGH NORTHEAST OF THE GREAT LAKES.
THE MODELS CONTINUE TO SHOW SPLIT FLOW SUNDAY/SUNDAY NIGHT WITH
RIDGING OVER THE FA MONDAY. EXPERIENCE WITH THIS PATTERN IS NOT
FAVORABLE FOR PRECIPITATION ACROSS THE FA. GOOD DYNAMICS ARE
INDICATED FOR SATURDAY NIGHT AS A SHORTWAVE COMES THROUGH THE FLOW.
HOWEVER, IT IS DIFFICULT TO JUSTIFY THE LARGE AMOUNTS OF SNOWFALL
THE GFS AND NAM ARE PRODUCING FOR THAT 12 HOUR TIME PERIOD WHICH
EQUATES TO ABOUT AN INCH PER HOUR FOR THE ENTIRE 12 HOUR PERIOD.
PLAN TO GO SOMEWHERE UNDER THOSE AMOUNTS TO OBTAIN A MORE REASONABLE
HOURLY SNOWFALL RATE. AT THIS TIME TOTAL SNOWFALL AMOUNTS SHOULD
RANGE FROM 2 INCHES NEAR HILL CITY AND MCCOOK TO 5 TO 9 INCHES IN AN
AREA SOUTHWEST OF A LINE FROM YUMA COLORADO TO LEOTI KANSAS. THESE
AMOUNTS INCLUDE UP TO 3 INCHES FROM SUNDAY THROUGH MONDAY WHICH MAY
TURN OUT TO BE LESS THAN THAT IF THE RIDGING MENTIONED ABOVE LIMITS
THE SNOWFALL. WIND SPEEDS WILL RANGE FROM 15 TO 25 MPH SATURDAY
NIGHT WITH SPEEDS DECREASING SUNDAY/SUNDAY NIGHT.
A WINTER STORM WARNING AND WINTER WEATHER ADVISORY HAS BEEN POSTED
FOR SATURDAY EVENING THROUGH SUNDAY EVENING. (SEE DETAILS BELOW).
MIN TEMPERATURES SATURDAY NIGHT SHOULD BE IN THE TEENS. COLDER MIN
TEMPERATURES IN THE SINGLE DIGITS ABOVE ZERO AND LOW TEENS ARE
EXPECTED SUNDAY NIGHT. MAX TEMPERATURES WILL BE IN THE TEENS SUNDAY
AND AROUND 20 ON MONDAY.
IN THE EXTENDED...(MONDAY NIGHT THROUGH FRIDAY)...THE FORECAST WILL
BE DRY MONDAY NIGHT AND TUESDAY WITH LACK ANY DYNAMICS UNDER
WESTERLY FLOW. THE PART OF THE TROUGH THAT SPLITS OFF OVER THE WEST
COAST WILL MOVE INTO THE DESERT SOUTHWEST TUESDAY AND ACROSS THE
CENTRAL/SOUTHERN PLAINS WEDNESDAY. THERE WILL BE A CHANCE TO SLIGHT
CHANCE OF LIGHT SNOW AS THIS TROUGH MOVES EAST THROUGH FRIDAY.
MIN TEMPERATURES MONDAY NIGHT THROUGH WEDNESDAY NIGHT WILL BE IN THE
TEENS. MIN TEMPERATURES THURSDAY NIGHT WILL BE IN THE SINGLE DIGITS
ABOVE ZERO. MAX TEMPERATURES TUESDAY AND WEDNESDAY SHOULD RANGE FROM
THE MID 30S TO 40. MAX TEMPERATURES THURSDAY AND FRIDAY WILL BE IN
THE 20S.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON)
ISSUED AT 1034 AM MST FRI FEB 20 2015
VFR CONDITIONS ARE EXPECTED THROUGH THE TAF PERIOD FOR BOTH
TERMINALS. BROKEN AND OVERCAST SKIES WILL BE PRESENT THROUGHOUT
THE ENTIRE PERIOD FOR BOTH TERMINALS WITH SOME LIGHT PRECIP
AFFECTING KGLD...WHICH WILL START AS RAIN AND TRANSITION TO SNOW
AFTER 6Z. RAIN/SNOW SHOWERS ARE EXPECTED AROUND MCCOOK...BUT
CONFIDENCE IS NOT HIGH ENOUGH YET TO INCLUDE DIRECT MENTION IN THE
TAF.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...WINTER WEATHER ADVISORY FROM 6 PM SATURDAY TO MIDNIGHT CST
SUNDAY NIGHT FOR KSZ001-002-014-015-028-029.
WINTER STORM WARNING FROM 5 PM MST /6 PM CST/ SATURDAY TO 11 PM
MST /MIDNIGHT CST/ SUNDAY FOR KSZ013-027-041-042.
CO...WINTER STORM WARNING FROM 5 PM SATURDAY TO 11 PM MST SUNDAY FOR
COZ090>092.
NE...WINTER WEATHER ADVISORY FROM 5 PM MST /6 PM CST/ SATURDAY TO 11
PM MST /MIDNIGHT CST/ SUNDAY FOR NEZ079-080.
&&
$$
SHORT TERM...MK
LONG TERM...FS
AVIATION...MK
AREA FORECAST DISCUSSION
NWS TOPEKA KS
1123 AM CST Fri Feb 20 2015
...AVIATION UPDATE...
.UPDATE...
Issued at 1030 AM CST FRI FEB 20 2015
12Z models data coming in and continue to show potential for mixed
precip this evening and overnight. Main uncertainty remains the
low level temp profile this evening and overnight with models all
within 1 to 2 C of freezing. The NAM is the colder solution which
would favor more snow. On the other hand the RAP tends to keep
surface temps above freezing and precip mainly rain through at
least 07Z. So with forecasts all within the margin of error, it
is difficult to predict the type of precip with much confidence
and would expect some combination of rain, freezing rain and snow
overnight.
As for accumulations the good news is with a weaker more
progressive system, models are not generating much moisture in
general with QPF amounts ranging from a couple hundredths over
north central KS to possibly a quarter of an inch over far
eastern KS. So worst case scenarios for accumulations would be 2 to
3 inches of snow or perhaps up to a quarter inch of ice
accumulation. Because the forecast anticipates mixed precip such
that precip is not all snow nor is it all ice, snow accumulations
are forecast be less than an inch and ice accumulations around a
tenth of an inch. This will probably be variable across northeast
and east central KS based on temps, but snow is more likely north
of I-70 and rain/freezing rain is more likely south of I-70. The
forecast anticipates the greatest impact to be west of a line from
Council Grove to Marysville.
Precip is still on track to come to an end before 8 AM Saturday
so the timing for the greatest impact remains during the evening
and overnight hours. Precip is expected to begin spreading north
across the area late this afternoon with temps above freezing. It
is between 7 PM and 10 PM when temps may fall to the freezing mark
and hazards start to be realized.
&&
.SHORT TERM...(Today and Tonight)
Issued at 248 AM CST FRI FEB 20 2015
The forecast for the short term remains quite challenging as we
continue to monitor the potential for a wintry mix of precipitation
tonight into Saturday morning.
At the surface, high pressure prevailed over the eastern U.S. with
low pressure situated over the Rockies, resulting in light
southeasterly winds, mostly clear to partly cloudy skies, and
temperatures early this morning plunging into the teens. Satellite
imagery showed a swath of low clouds stretching across Arkansas and
eastern Oklahoma as southerly flow in that region continued to
advect moisture northward. How quickly this cloud cover lifts into
the region and how expansive the cloud cover becomes will have a
significant impact on temperatures today. Current forecast has highs
reaching into the mid 30s to mid 40s from east to west, however if
the region quickly becomes blanketed by cloud cover then
temperatures may only reach into low to upper 30s. Model soundings
show increasing low level moisture in east central Kansas by mid to
late morning and continuing through this afternoon, so expect some
patchy freezing drizzle initially before warming up enough for
drizzle or even light rain this afternoon for locations generally
along and south of I-35. Moisture advection will strengthen by this
evening with light precipitation overspreading the region from south
to north. An advancing mid-level trough will help to push a cold
front through the region tonight into the early overnight hours, and
moisture associated with this boundary is expected to converge with
the southern stream moisture by mid to late evening. The last couple
of model runs have trended toward a faster departure of
precipitation from west to east so have decreased POPs across north
central Kansas during the overnight hours. The precipitation type
forecast continues to be quite challenging for tonight as it will be
very dependent upon how much we warm up today and at what rate
temperatures cool to near and below freezing tonight. As a result,
confidence in the precipitation type and QPF forecasts is
unfortunately still low. In general, focus has shifted more toward
concerns for ice accumulations with lesser snow accumulations than
previously expected. Expect areas of rain to gradually transition
to a wintry mix of freezing rain, sleet, and snow across most
locations. Locations along and south of I-35 should see predominantly
rain, freezing rain, and sleet, while locations north of I-35 should
see more of a mix of freezing rain, sleet, and snow. At this time,
snow accumulations look to be around one-half inch or less. Ice
accumulations upwards of around one tenth of an inch are possible
along and south of I-35 with lesser amounts to the north. With these
concerns for ice accumulations and the associated hazardous travel
conditions, a Winter Weather Advisory has been issued for counties
in far northeast and east central Kansas from 6pm tonight through
9am Saturday.
.LONG TERM...(Saturday through Thursday)
Issued at 248 AM CST FRI FEB 20 2015
Saturday morning may have a bit of lingering precipitation, but
should dry out quickly after sunrise (if not earlier). If any
precip does linger, temperatures are likely to be very near the
freezing mark with slightly warmer temperatures aloft so have a
mix of precip types possible. There also seems to be some
potential for flurries behind the main precip area and
particularly in north central KS so have included a mention of
that in the forecast for early Saturday as well. Otherwise, the
remainder of Saturday through Monday is dominated by strong
surface high pressure. This low level airmass will also be quite
dry and quite cold. The dry air will impact the forecast markedly
as there is persistent weak vertical motion aloft in central KS
through this period, but will likely result in little more than
virga over the local forecast area. Will need to monitor the
situation as minor changes in the forecast could result in a
persistent but light snow on the western and southern edges of the
forecast area...but this appears to be quite unlikely at this
time. Sunday looks to be the coldest day of the period as the high
pressure settles directly overhead. Clouds will keep daytime temps
cool, and if any clearing takes place Sunday night, the current
single digit forecast may be too warm.
By late in the forecast period, a disturbance or series of
disturbances appears set to eject from the southwestern CONUS
across the central Plains. This also appears, similar to so many
storm systems this winter, likely to interact with a trough diving
south into the region at the same general time. That said, the
interactions of these features result in another low confidence
forecast with fluctuations likely over the next few days. The take
away point would be that another round of winter weather is
possible by the second half of the work week, potentially focused
around the Thursday time frame.
&&
.AVIATION...(For the 18Z TAFs through 18Z Saturday Afternoon)
Issued at 1123 AM CST FRI FEB 20 2015
Confidence is good that IFR conditions will move into the
terminals by this evening. OBS upstream are already showing CIGS
around 1 KFT. Biggest uncertainty remains precip type. Think there
will be a mix or rain, freezing rain and snow during the
overnight. Think the precip will come to an end by 12Z. Have
trended optimistic with CIGS improving tomorrow morning, but there
is a chance for stratocu to hang in between 1 and 2 KFT through
the morning. See above discussion for further details.
&&
.TOP WATCHES/WARNINGS/ADVISORIES...
WINTER WEATHER ADVISORY from 6 PM this evening to 9 AM CST
Saturday FOR KSZ012-024-026-038>040-054>056-058-059.
&&
$$
UPDATE...Wolters
SHORT TERM...Hennecke
LONG TERM...Barjenbruch
AVIATION...Wolters
AREA FORECAST DISCUSSION
NWS TOPEKA KS
1030 AM CST Fri Feb 20 2015
.UPDATE...
Issued at 1030 AM CST FRI FEB 20 2015
12Z models data coming in and continue to show potential for mixed
precip this evening and overnight. Main uncertainty remains the
low level temp profile this evening and overnight with models all
within 1 to 2 C of freezing. The NAM is the colder solution which
would favor more snow. On the other hand the RAP tends to keep
surface temps above freezing and precip mainly rain through at
least 07Z. So with forecasts all within the margin of error, it
is difficult to predict the type of precip with much confidence
and would expect some combination of rain, freezing rain and snow
overnight.
As for accumulations the good news is with a weaker more
progressive system, models are not generating much moisture in
general with QPF amounts ranging from a couple hundredths over
north central KS to possibly a quarter of an inch over far
eastern KS. So worst case scenarios for accumulations would be 2 to
3 inches of snow or perhaps up to a quarter inch of ice
accumulation. Because the forecast anticipates mixed precip such
that precip is not all snow nor is it all ice, snow accumulations
are forecast be less than an inch and ice accumulations around a
tenth of an inch. This will probably be variable across northeast
and east central KS based on temps, but snow is more likely north
of I-70 and rain/freezing rain is more likely south of I-70. The
forecast anticipates the greatest impact to be west of a line from
Council Grove to Marysville.
Precip is still on track to come to an end before 8 AM Saturday
so the timing for the greatest impact remains during the evening
and overnight hours. Precip is expected to begin spreading north
across the area late this afternoon with temps above freezing. It
is between 7 PM and 10 PM when temps may fall to the freezing mark
and hazards start to be realized.
&&
.SHORT TERM...(Today and Tonight)
Issued at 248 AM CST FRI FEB 20 2015
The forecast for the short term remains quite challenging as we
continue to monitor the potential for a wintry mix of precipitation
tonight into Saturday morning.
At the surface, high pressure prevailed over the eastern U.S. with
low pressure situated over the Rockies, resulting in light
southeasterly winds, mostly clear to partly cloudy skies, and
temperatures early this morning plunging into the teens. Satellite
imagery showed a swath of low clouds stretching across Arkansas and
eastern Oklahoma as southerly flow in that region continued to
advect moisture northward. How quickly this cloud cover lifts into
the region and how expansive the cloud cover becomes will have a
significant impact on temperatures today. Current forecast has highs
reaching into the mid 30s to mid 40s from east to west, however if
the region quickly becomes blanketed by cloud cover then
temperatures may only reach into low to upper 30s. Model soundings
show increasing low level moisture in east central Kansas by mid to
late morning and continuing through this afternoon, so expect some
patchy freezing drizzle initially before warming up enough for
drizzle or even light rain this afternoon for locations generally
along and south of I-35. Moisture advection will strengthen by this
evening with light precipitation overspreading the region from south
to north. An advancing mid-level trough will help to push a cold
front through the region tonight into the early overnight hours, and
moisture associated with this boundary is expected to converge with
the southern stream moisture by mid to late evening. The last couple
of model runs have trended toward a faster departure of
precipitation from west to east so have decreased POPs across north
central Kansas during the overnight hours. The precipitation type
forecast continues to be quite challenging for tonight as it will be
very dependent upon how much we warm up today and at what rate
temperatures cool to near and below freezing tonight. As a result,
confidence in the precipitation type and QPF forecasts is
unfortunately still low. In general, focus has shifted more toward
concerns for ice accumulations with lesser snow accumulations than
previously expected. Expect areas of rain to gradually transition
to a wintry mix of freezing rain, sleet, and snow across most
locations. Locations along and south of I-35 should see predominantly
rain, freezing rain, and sleet, while locations north of I-35 should
see more of a mix of freezing rain, sleet, and snow. At this time,
snow accumulations look to be around one-half inch or less. Ice
accumulations upwards of around one tenth of an inch are possible
along and south of I-35 with lesser amounts to the north. With these
concerns for ice accumulations and the associated hazardous travel
conditions, a Winter Weather Advisory has been issued for counties
in far northeast and east central Kansas from 6pm tonight through
9am Saturday.
.LONG TERM...(Saturday through Thursday)
Issued at 248 AM CST FRI FEB 20 2015
Saturday morning may have a bit of lingering precipitation, but
should dry out quickly after sunrise (if not earlier). If any
precip does linger, temperatures are likely to be very near the
freezing mark with slightly warmer temperatures aloft so have a
mix of precip types possible. There also seems to be some
potential for flurries behind the main precip area and
particularly in north central KS so have included a mention of
that in the forecast for early Saturday as well. Otherwise, the
remainder of Saturday through Monday is dominated by strong
surface high pressure. This low level airmass will also be quite
dry and quite cold. The dry air will impact the forecast markedly
as there is persistent weak vertical motion aloft in central KS
through this period, but will likely result in little more than
virga over the local forecast area. Will need to monitor the
situation as minor changes in the forecast could result in a
persistent but light snow on the western and southern edges of the
forecast area...but this appears to be quite unlikely at this
time. Sunday looks to be the coldest day of the period as the high
pressure settles directly overhead. Clouds will keep daytime temps
cool, and if any clearing takes place Sunday night, the current
single digit forecast may be too warm.
By late in the forecast period, a disturbance or series of
disturbances appears set to eject from the southwestern CONUS
across the central Plains. This also appears, similar to so many
storm systems this winter, likely to interact with a trough diving
south into the region at the same general time. That said, the
interactions of these features result in another low confidence
forecast with fluctuations likely over the next few days. The take
away point would be that another round of winter weather is
possible by the second half of the work week, potentially focused
around the Thursday time frame.
&&
.AVIATION...(For the 12Z TAFs through 12Z Saturday Morning)
Issued at 536 AM CST FRI FEB 20 2015
For the 12Z TAFs, MVFR CIGS should lift northward toward the TAF
sites by late morning or early afternoon with areas of light rain
developing by late this afternoon into early evening. The forecast
for precipitation type through the evening and overnight hours will
be quite challenging as a wintry mix of freezing rain, sleet, and
snow is possible. This wintry mix of precipitation should continue
into Saturday morning, and hopefully future updates will be able to
further pinpoint the timing of various precipitation types. With the
mixed precipitation, CIGS/VSBY should drop to IFR conditions but
cannot rule out periods of near LIFR conditions. Once a cold front
tracks through the area tonight, southeasterly winds will gradually
back to the north-northwest by Saturday morning.
&&
.TOP WATCHES/WARNINGS/ADVISORIES...
WINTER WEATHER ADVISORY from 6 PM this evening to 9 AM CST
Saturday FOR KSZ012-024-026-038>040-054>056-058-059.
&&
$$
UPDATE...Wolters
SHORT TERM...Hennecke
LONG TERM...Barjenbruch
AVIATION...Hennecke
AREA FORECAST DISCUSSION
NWS PADUCAH KY
1152 AM CST FRI FEB 20 2015
.UPDATE...
ISSUED AT 1151 AM CST FRI FEB 20 2015
THE AVIATION SECTION HAS BEEN UPDATED FOR THE 18Z TAF ISSUANCE.
UPDATE ISSUED AT 1100 AM CST FRI FEB 20 2015
ALREADY GETTING FREEZING RAIN AND SLEET OVER MUCH OF SOUTHEAST
MISSOURI THIS MORNING. SEE NO REASON WHY PRECIPITATION TYPES WILL
TREND COLDER THROUGH THE DAY...SO TRIED TO PUSH SLEET AND FREEZING
RAIN NORTHEAST ACROSS THE AREA A BIT FASTER THROUGH THE AFTERNOON.
THE PRECIPITATION HAS BEEN QUITE SHOWERY OVER SOUTHWEST PORTIONS
OF THE AREA...AND THE HRRR AND WRF RUNS INDICATE THAT THAT WILL
CONTINUE THROUGH THE DAY. DO NOT ANTICIPATE ANY CHANGES TO
HEADLINES AT THIS TIME.
UPDATE ISSUED AT 755 AM CST FRI FEB 20 2015
UPDATED THE FORECAST TO REFLECT CURRENT CONDITIONS AND LATEST
SHORT TERM MODEL DATA. THOUGH SOME MEASURABLE PCPN MAY FALL MAINLY
WEST OF THE MS RIVER IN THE MORNING...MOST OF THE PCPN WILL
PROBABLY WAIT UNTIL THE AFTERNOON TO SPREAD NEWD ACROSS THE REGION
TODAY.
ALSO UPDATED THE AVIATION DISCUSSION.
&&
.SHORT TERM...(TODAY THROUGH SATURDAY NIGHT)
ISSUED AT 430 AM CST FRI FEB 20 2015
SO FAR...THE DEVELOPING WARM ADVECTION PATTERN DEVELOPING OVER THE
PAH FORECAST AREA HAS YIELDED MID CLOUDINESS AND NOTHING
MEASURABLE AT THE GROUND. HOWEVER...THAT IS EXPECTED TO CHANGE
PRIMARILY THIS AFTERNOON. MODEL SOUNDINGS INDICATE THAT THE PCPN
WILL START OUT AS SNOW...WITH SLEET INCREASINGLY MIXED IN MAINLY WEST
OF THE MS RIVER.
THE MOST INTERESTING TIME FRAME WILL BE THIS EVENING...WHEN WARM
AIR CONTINUES TO MOVE IN ALOFT. HOW MUCH DEPENDS ON WHICH MODEL
YOU BELIEVE. THE NAM HAD A MORE PRONOUNCED WARM TONGUE...BUT ALSO
COLDER SFC TEMPS THAN THE GFS...FOR EXAMPLE. SFC TEMP GRIDS WERE
BASED ON A BLEND OF MODEL DATA...AND THE FORECAST PCPN-TYPE WAS
BASED ON A COMPROMISE MAINLY BETWEEN THE GFS AND THE NAM. IT IS
BELIEVED THAT PCPN LOADING WILL PLAY A PART IN WARMING TEMPS
ACROSS THE REGION DURING THE EVENING.
AT THIS TIME...IN THE EVENING...AS THE SNOWFALL IS GRADUALLY
REPLACED BY A WINTRY MIX...IT APPEARS THE WINDOW OF OPPORTUNITY
FOR FREEZING RAIN...AND ICE ACCRETION...WILL BE RATHER NARROW.
EXCEPT FOR AREAS NORTH OF I-64...A FEW HOURS OF FREEZING RAIN IS
FORECAST IN THE EVENING ONLY. NORTH OF I-64...TIMING SHOULD BE
DELAYED UNTIL SHORTLY AFTER MIDNIGHT.
AS A VIGOROUS LOW PRESSURE SYSTEM PASSES THROUGH THE REGION ON
SAT...ALL RAIN SHOULD BE UNDERWAY AFTER DAYBREAK...WITH A
POSSIBILITY OF SOME HEAVY RAINFALL RATES ACROSS ROUGHLY THE SRN
THIRD OF THE PAH FORECAST AREA. A THUNDERSTORM OR TWO CANNOT BE
RULED OUT. PCPN WILL COME TO A RAPID END SAT NIGHT...WITH A
POSSIBLE WINTRY MIX FOR WRN KY LATE BEFORE DAYBREAK AS TEMPS CRASH
AGAIN BELOW FREEZING.
TOTAL SNOW AND SLEET ACCUMULATION IS EXPECTED TO BE GENERALLY
BETWEEN 1/2 INCH AND 2 INCHES.
THE MOST ICE ACCRETION SHOULD OCCUR NEAR THE TN STATE LINE...UP TO
AROUND 0.10 INCH...SOMEWHAT LESSER AMOUNTS OVER THE SRN HALF OF
SERN MO AND THE PURCHASE AREA OF KY...AND MAYBE A HUNDREDTH OF AN
INCH POSSIBLE ELSEWHERE.
.LONG TERM...(SUNDAY THROUGH THURSDAY)
ISSUED AT 430 AM CST FRI FEB 20 2015
LITTLE TO NO CHANGE TO THE UPPER AIR PATTERN IN THE LONG TERM.
PERSISTENT RIDGE OVER THE PACIFIC OFF THE WEST COAST AND LOW CENTERS
FROM GREENLAND TO HUDSON BAY WILL KEEP BROAD TROF AND LOW HEIGHTS
ACROSS MUCH OF THE NATION ESPECIALLY EAST OF THE ROCKIES. MAINLY DRY
WEATHER IS FORECAST WITH BELOW NORMAL TEMPERATURES. TWO MINOR
SYSTEMS COULD AFFECT THE AREA...ONE MONDAY NIGHT...WITH THE SECOND
THURSDAY INTO THURSDAY NIGHT. ONLY HAVE SLIGHT CHANCES IN FOR
THURSDAY AT THIS TIME FOR LIGHT SNOW.
&&
.AVIATION...
ISSUED AT 1151 AM CST FRI FEB 20 2015
THE FORECAST IS STILL ON TRACK WITH A RAPID WARMING TREND EXPECTED
THROUGH TONIGHT. ALL TAFS SHOULD SEE DETERIORATING CONDITIONS
TONIGHT WITH PRECIPITATION TYPE TRANSITIONING FROM SLEET/SNOW TO
FREEZING AND EVENTUALLY ALL RAIN BY 06Z. LOW CONFIDENCE ON WINDS
WITH A SURFACE TROUGH DEVELOPING NORTHEAST RIGHT ACROSS THE
TERMINALS. CANNOT RULE OUT SOME SOUTHERLY GUSTS TONIGHT.
&&
.PAH WATCHES/WARNINGS/ADVISORIES...
IL...WINTER WEATHER ADVISORY UNTIL 6 AM CST SATURDAY FOR ILZ075>078-
080>094.
MO...WINTER WEATHER ADVISORY UNTIL 6 AM CST SATURDAY FOR MOZ076-086-
087-100-107>112-114.
IN...WINTER WEATHER ADVISORY UNTIL 6 AM CST SATURDAY FOR INZ081-082-
085>088.
KY...WINTER WEATHER ADVISORY UNTIL 6 AM CST SATURDAY FOR KYZ001>022.
&&
$$
UPDATE...DRS
SHORT TERM...DB
LONG TERM...CN
AVIATION...DRS
AREA FORECAST DISCUSSION
NWS PADUCAH KY
1100 AM CST FRI FEB 20 2015
.UPDATE...
ISSUED AT 1100 AM CST FRI FEB 20 2015
ALREADY GETTING FREEZING RAIN AND SLEET OVER MUCH OF SOUTHEAST
MISSOURI THIS MORNING. SEE NO REASON WHY PRECIPITATION TYPES WILL
TREND COLDER THROUGH THE DAY...SO TRIED TO PUSH SLEET AND FREEZING
RAIN NORTHEAST ACROSS THE AREA A BIT FASTER THROUGH THE AFTERNOON.
THE PRECIPITATION HAS BEEN QUITE SHOWERY OVER SOUTHWEST PORTIONS
OF THE AREA...AND THE HRRR AND WRF RUNS INDICATE THAT THAT WILL
CONTINUE THROUGH THE DAY. DO NOT ANTICIPATE ANY CHANGES TO
HEADLINES AT THIS TIME.
UPDATE ISSUED AT 755 AM CST FRI FEB 20 2015
UPDATED THE FORECAST TO REFLECT CURRENT CONDITIONS AND LATEST
SHORT TERM MODEL DATA. THOUGH SOME MEASURABLE PCPN MAY FALL MAINLY
WEST OF THE MS RIVER IN THE MORNING...MOST OF THE PCPN WILL
PROBABLY WAIT UNTIL THE AFTERNOON TO SPREAD NEWD ACROSS THE REGION
TODAY.
ALSO UPDATED THE AVIATION DISCUSSION.
&&
.SHORT TERM...(TODAY THROUGH SATURDAY NIGHT)
ISSUED AT 430 AM CST FRI FEB 20 2015
SO FAR...THE DEVELOPING WARM ADVECTION PATTERN DEVELOPING OVER THE
PAH FORECAST AREA HAS YIELDED MID CLOUDINESS AND NOTHING
MEASURABLE AT THE GROUND. HOWEVER...THAT IS EXPECTED TO CHANGE
PRIMARILY THIS AFTERNOON. MODEL SOUNDINGS INDICATE THAT THE PCPN
WILL START OUT AS SNOW...WITH SLEET INCREASINGLY MIXED IN MAINLY WEST
OF THE MS RIVER.
THE MOST INTERESTING TIME FRAME WILL BE THIS EVENING...WHEN WARM
AIR CONTINUES TO MOVE IN ALOFT. HOW MUCH DEPENDS ON WHICH MODEL
YOU BELIEVE. THE NAM HAD A MORE PRONOUNCED WARM TONGUE...BUT ALSO
COLDER SFC TEMPS THAN THE GFS...FOR EXAMPLE. SFC TEMP GRIDS WERE
BASED ON A BLEND OF MODEL DATA...AND THE FORECAST PCPN-TYPE WAS
BASED ON A COMPROMISE MAINLY BETWEEN THE GFS AND THE NAM. IT IS
BELIEVED THAT PCPN LOADING WILL PLAY A PART IN WARMING TEMPS
ACROSS THE REGION DURING THE EVENING.
AT THIS TIME...IN THE EVENING...AS THE SNOWFALL IS GRADUALLY
REPLACED BY A WINTRY MIX...IT APPEARS THE WINDOW OF OPPORTUNITY
FOR FREEZING RAIN...AND ICE ACCRETION...WILL BE RATHER NARROW.
EXCEPT FOR AREAS NORTH OF I-64...A FEW HOURS OF FREEZING RAIN IS
FORECAST IN THE EVENING ONLY. NORTH OF I-64...TIMING SHOULD BE
DELAYED UNTIL SHORTLY AFTER MIDNIGHT.
AS A VIGOROUS LOW PRESSURE SYSTEM PASSES THROUGH THE REGION ON
SAT...ALL RAIN SHOULD BE UNDERWAY AFTER DAYBREAK...WITH A
POSSIBILITY OF SOME HEAVY RAINFALL RATES ACROSS ROUGHLY THE SRN
THIRD OF THE PAH FORECAST AREA. A THUNDERSTORM OR TWO CANNOT BE
RULED OUT. PCPN WILL COME TO A RAPID END SAT NIGHT...WITH A
POSSIBLE WINTRY MIX FOR WRN KY LATE BEFORE DAYBREAK AS TEMPS CRASH
AGAIN BELOW FREEZING.
TOTAL SNOW AND SLEET ACCUMULATION IS EXPECTED TO BE GENERALLY
BETWEEN 1/2 INCH AND 2 INCHES.
THE MOST ICE ACCRETION SHOULD OCCUR NEAR THE TN STATE LINE...UP TO
AROUND 0.10 INCH...SOMEWHAT LESSER AMOUNTS OVER THE SRN HALF OF
SERN MO AND THE PURCHASE AREA OF KY...AND MAYBE A HUNDREDTH OF AN
INCH POSSIBLE ELSEWHERE.
.LONG TERM...(SUNDAY THROUGH THURSDAY)
ISSUED AT 430 AM CST FRI FEB 20 2015
LITTLE TO NO CHANGE TO THE UPPER AIR PATTERN IN THE LONG TERM.
PERSISTENT RIDGE OVER THE PACIFIC OFF THE WEST COAST AND LOW CENTERS
FROM GREENLAND TO HUDSON BAY WILL KEEP BROAD TROF AND LOW HEIGHTS
ACROSS MUCH OF THE NATION ESPECIALLY EAST OF THE ROCKIES. MAINLY DRY
WEATHER IS FORECAST WITH BELOW NORMAL TEMPERATURES. TWO MINOR
SYSTEMS COULD AFFECT THE AREA...ONE MONDAY NIGHT...WITH THE SECOND
THURSDAY INTO THURSDAY NIGHT. ONLY HAVE SLIGHT CHANCES IN FOR
THURSDAY AT THIS TIME FOR LIGHT SNOW.
&&
.AVIATION...
ISSUED AT 755 AM CST FRI FEB 20 2015
SERLY WINDS AROUND 10 KTS AND VFR CIGS WILL BE THE RULE THROUGH
THE MORNING. THE DEVELOPING WARM ADVECTION PATTERN AHEAD OF A
VIGOROUS LOW PRESSURE SYSTEM...WILL FORCE CIGS TO DROP TO MVFR
LEVELS IN THE EARLY AFTERNOON IN THE WRN HALF OF THE REGION. ERN
TERMINALS WILL FOLLOW BY THE LATE AFTERNOON/EARLY EVENING. THE
MOST SIGNIFICANT ELEMENT WILL BE PCPN TYPE. A WINTRY MIX IS
FORECAST TODAY AND TONIGHT...WITH A FEW HOURS OF PRIMARILY
FREEZING RAIN LIKELY TO OCCUR STARTING AROUND SUNSET AT WRN
TERMINALS...AND MID EVENING AT THE ERN TERMINALS.
&&
.PAH WATCHES/WARNINGS/ADVISORIES...
IL...WINTER WEATHER ADVISORY UNTIL 6 AM CST SATURDAY FOR ILZ075>078-
080>094.
MO...WINTER WEATHER ADVISORY UNTIL 6 AM CST SATURDAY FOR MOZ076-086-
087-100-107>112-114.
IN...WINTER WEATHER ADVISORY UNTIL 6 AM CST SATURDAY FOR INZ081-082-
085>088.
KY...WINTER WEATHER ADVISORY UNTIL 6 AM CST SATURDAY FOR KYZ001>022.
&&
$$
UPDATE...DRS
SHORT TERM...DB
LONG TERM...CN
AVIATION...DB
AREA FORECAST DISCUSSION
NWS PADUCAH KY
1018 PM CST THU FEB 19 2015
.UPDATE...
ISSUED AT 1018 PM CST THU FEB 19 2015
HAD TO MAKE A LAST MINUTE COLLABORATION CHANGE FOR POPS/WEATHER
FOR THE REST OF TONIGHT. MAIN FOCUS WAS TO REDUCE SNOW CHANCES
THROUGH MOST OF THE NIGHT, INCREASING POPS FROM THE
SOUTH/SOUTHWEST AROUND DAYBREAK. OTHERWISE, NO CHANGES WERE MADE
FROM EARLIER TEMPERATURE, WIND, AND DEWPOINT CHANGES.
&&
.SHORT TERM...(THIS EVENING THROUGH SUNDAY)
ISSUED AT 247 PM CST THU FEB 19 2015
...TONIGHT THROUGH FRIDAY...
RADAR/OBS NETWORK SHOWS SOME 20DBZ PLUS ECHOES IN WESTERN MO
PRODUCING LIGHT SNOW AT TIMES. THE RUN TO RUN MODEL TRENDS HAVE BEEN
CONSISTENTLY BRINGING THIS PCPN INTO SEMO OVERNIGHT...IMPACTING SEMO
AND NEARBY SWIL/FAR SWKY. WITH THE LOWER 3K FEET REMAINING QUITE
DRY...THE END RESULT IS AN ADJUSTED SNOW ACCUMULATION FORECAST GRID
TOTAL TONITE OF NOT MORE THAN ABOUT A HALF INCH OR SO FOR THAT
AREA...BASED ON LIQUID QPF OF 2-3 HUNDREDTHS OF AN INCH.
ON TO FRIDAY...WARMING ALOFT IS NOTED...AND THE SOUNDINGS LIKEWISE
SHOW DRYING IN THE -10C TO -20C LAYER AS THIS OCCURS. THE WARM NOSE
GROWS ABOUT 4K FEET THICK IN THE APPROX 3K-7K FEET ALOFT LAYER (AT
ITS PEAK)...AND THE END RESULT IS A TRANSITION FROM SNOW TO SLEET
FOR ALL AS THE DAY WEARS ON. LIQUID QPF YIELDS COMBO SNOW/ICE TOTALS
IN MAINLY THE SOUTH/WEST HALF OF ABOUT 1/2 INCH TO 3/4 INCH SWATH
AVERAGE AMOUNTS ACROSS FAR SEMO/SOUTHERN-MOST SOUTHWEST KY DURING
THIS TIME FRAME. FURTHER NORTH/EAST...IT APPEARS TO BE STILL TOO
COLD/KEPT ALL SNOW MENTION...THOUGH WE ACKNOWLEDGE THIS STARTS TO
CHANGE CLOSE TO 00Z SATURDAY (AROUND 22-23Z FRIDAY) AS YOU MOVE
EAST OF THE LAKES.
...FRIDAY NIGHT THROUGH SUNDAY...
THE 12Z GFS AND ECMWF ARE IN VERY GOOD AGREEMENT IN THE
LOCATION/PATH OF THE SURFACE LOW/TROUGH FRIDAY NIGHT THROUGH
SATURDAY. THIS FORECAST CLOSELY FOLLOWS A BLEND OF THESE TWO
MODELS.
THERE ARE A FEW NOTABLE CHANGES FROM YESTERDAY. THE ELEVATED
INSTABILITY IN THE GFS IS SOUTH OF THE REGION...BUT THE ECMWF
STILL HAS SOME IN THE SOUTHERN THIRD OF THE AREA LATE FRIDAY NIGHT
AND SATURDAY. SPC`S DAY 2 STILL HAS THAT AREA IN GENERAL
THUNDER...SO KEPT A MENTION.
THE GFS IS WETTER THAN THE ECMWF...BUT THE HEAVIEST RAINS ARE
TRENDING SOUTHEAST. WITH THIS TREND IN MIND AND ALL OF THE WINTER
QUESTIONS IN THE MEANTIME...WILL NOT BE ISSUING ANY FLOOD RELATED
PRODUCTS WITH THIS FORECAST PACKAGE. WE WILL CONTINUE TO MENTION
THE CONCERN IN THE HWO.
AS FOR THE WINTER MESS. DECIDED TO GO WITH A WINTER STORM WATCH
FOR THE ENTIRE AREA FROM 18Z FRIDAY TO 12Z SATURDAY. STILL HAVING
A HARD TIME COMING UP WITH SIGNIFICANT SNOW/SLEET OR ICE
ACCUMULATIONS...BUT WE WILL SEE SOME OF ALL THREE PRECIPITATION
TYPES...AND THE POTENTIAL IS THERE FOR SOME AREAS TO REACH WARNING
CRITERIA FOR THE COMBINATION OF ICE AND SNOW/SLEET.
WE ARE STILL VERY CONCERNED ABOUT THE ICING POTENTIAL FRIDAY
NIGHT...BUT THE ECMWF AND GFS CONTINUE TO BE VERY AGGRESSIVE IN
WARMING TEMPERATURES ABOVE FREEZING OVER THE ENTIRE AREA BY 12Z
SATURDAY. FIGURE THAT ANY ICING ISSUES WILL BE SHORT-LIVED IN THIS
SCENARIO. HOWEVER...WE WILL CONTINUE TO MONITOR FUTURE RUNS FOR A
SHIFT IN THE PATH OF THE SURFACE LOW.
THE 12Z NAM WAS QUITE COLD AND CERTAINLY IS NOT UNBELIEVABLE. IT
IS AN OUTLIER AT THIS TIME...SO WILL CONSIDER IT TO BE THE COLD
END OF THE RANGE OF POSSIBILITIES...BUT WILL STAY WITH THE
MAJORITY OF GUIDANCE WHICH IS MORE IN LINE WITH THE EXISTING
FORECAST.
THE 12Z MODELS ARE IN AGREEMENT IN PUSHING THE PRECIPITATION
MOSTLY EAST OF THE AREA BY 06Z SUNDAY...SO THERE IS NOT MUCH TIME
FOR A CHANGE OVER TO SNOW OR FREEZING RAIN BEFORE THE
PRECIPITATION COMES TO AN END. WILL MENTION THE CHANGE OVER...BUT
WITH LITTLE OR NO ICE/SNOW ACCUMULATION.
AS FOR TEMPERATURES...TRENDED DOWNWARD A BIT FOR SATURDAY...BUT
STILL ABOVE FREEZING. ALSO TRENDED DOWNWARD FOR SATURDAY NIGHT AND
SUNDAY...AS ANOTHER MAJOR SURFACE HIGH SETTLES OVER THE REGION.
.LONG TERM...(SUNDAY NIGHT THROUGH THURSDAY)
ISSUED AT 247 PM CST THU FEB 19 2015
THIS TIME FRAME IS LARGELY DESCRIBED AS A DRY/COLD PORTION OF THE
FORECAST. WE`LL BE ON THE BACKSIDE OF THE DEPARTING SYSTEM SUNDAY
WITH ITS REINFORCED ARCTIC AIR FUNNELING IN...CREATING SUNDAY HIGHS
IN THE 20S NORTH...TAPERING TO LOWER 30S SOUTH/EAST. THE ARCTIC AIR
COMES IN FULL FORCE ON AS A 1040-45MB SURFACE HIGH BUILDS ACROSS THE
OHIO VALLEY. RESULTANT LOWS WILL FALL INTO THE SINGLE DIGITS/EVEN
NEAR ZERO NORTH...AND LOWER TEENS SOUTH...SUNDAY NIGHT.
CORRESPONDING NEXT DAY LOWS UNDER SAME HIGH PRESSURE SYSTEM RANGE
FROM TEENS NORTH TO 20S SOUTH.
THE HIGH MOVES EAST BY MID WEEK AND WE START TO MODERATE BEFORE THE
NEXT REINFORCING COLD SHOT. IT STILL LOOKS DRY...BUT PCPN CHANCES DO
EXIST JUST BEYOND THE FA...AND MAY END UP YIELDING A SMALL CHANCE
MENTION HERE OR THERE BEFORE ALL IS SAID AND DONE. STILL
LARGELY...THE DRY FORECAST SHOULD HOLD...AS WELL AS COLD...EVEN WITH
MODERATION...WITH TUE-WED HIGHS IN THE 30S AND LOWS IN THE TEENS.
LONGER RANGE INDICATORS SUGGEST A REINFORCED SHOT OF COLD TOWARD THE
END OF THE WEEK...WITH HIGHS BACK IN THE 20S AND LOWS IN THE SINGLE
DIGITS BY DAY 7 (OR 8).
&&
.AVIATION...
ISSUED AT 543 PM CST THU FEB 19 2015
THE 3KM HRRR MODEL GUIDANCE IS INITIALIZING A LITTLE FURTHER
SOUTHWEST THAN THE 0.5 DEGREE NWS RADAR MOSAIC REFLECTIVITY FOR
SNOW THIS AFTERNOON OVER MISSOURI. WILL BE WATCHING THE 18-25DBZ
BANDS FOR SATURATING THE MID-DECK FOR SNOW REACHING THE SURFACE.
AT THIS POINT, WILL WATCH THE EVOLUTION OF THE EASTWARD MOVING
SNOW BANDS FOR THE NEED TO ACCELERATE THE ONSET OF LOWER VFR
CEILINGS, ESPECIALLY AT KCGI/KPAH. OTHERWISE, DO NOT PLAN TO
INTRODUCE MVFR CEILINGS UNTIL AFTER 12Z, WITH THE ONSET OF SNOW
WITHIN 2-3 HOURS AFTER THE BEGINNING OF THE MVFR CEILINGS.
&&
.PAH WATCHES/WARNINGS/ADVISORIES...
IL...WINTER STORM WATCH FROM FRIDAY AFTERNOON THROUGH LATE FRIDAY
NIGHT FOR ILZ075>078-080>094.
MO...WINTER STORM WATCH FROM FRIDAY AFTERNOON THROUGH LATE FRIDAY
NIGHT FOR MOZ076-086-087-100-107>112-114.
IN...WINTER STORM WATCH FROM FRIDAY AFTERNOON THROUGH LATE FRIDAY
NIGHT FOR INZ081-082-085>088.
KY...WINTER STORM WATCH FROM FRIDAY AFTERNOON THROUGH LATE FRIDAY
NIGHT FOR KYZ001>022.
&&
$$
UPDATE...SMITH
SHORT TERM...DRS/DH
LONG TERM...DH
AVIATION...SMITH
AREA FORECAST DISCUSSION
NWS GRAY ME
1056 PM EST SAT FEB 21 2015
.SYNOPSIS...
LOW PRESSURE WILL BRING SNOW TO THE AREA TONIGHT. A COLD FRONT
WILL MOVE THROUGH SUNDAY WITH COLD AIR FOR THE START OF THE WEEK.
ARCTIC HIGH PRESSURE WILL BUILD EAST INTO THE AREA MONDAY INTO
TUESDAY. LOW PRESSURE WILL CROSS THE AREA TUESDAY NIGHT INTO
WEDNESDAY. MORE HIGH PRESSURE FOLLOWS THIS SYSTEM FOR THURSDAY
INTO THE START OF NEXT WEEKEND.
&&
.NEAR TERM /UNTIL 6 AM SUNDAY MORNING/...
11 PM UPDATE...HAVE UPDATED THE SNOWFALL FORECAST BASED ON LATEST
TRENDS IN RADAR DATA AND SFC OBSERVATIONS. A LULL IN ACTIVITY
ACROSS SOUTHEASTERN NH AND COASTAL SOUTHERN ME HAS CONTINUED...AS
WELL AS WARMING TEMPERATURES. HAVE THEREFORE LOWERED SNOWFALL
AMOUNTS IN THESE AREAS A BIT. HAVE INCREASED SNOWFALL TOTALS
SLIGHTLY IN A CORRIDOR FROM GRAFTON COUNTY NH EASTWARD TO
LEWISTON ME TO WALDO COUNTY ME. THIS IS WHERE PERSISTENT BANDING
HAS OCCURRED OVER THE LAST COUPLE OF HOURS. OTHERWISE...THE
FORECAST REMAINS LARGELY UNCHANGED.
9 PM UPDATE...HAVE UPDATED POPS AND SNOWFALL AS WELL AS
TEMPERATURES BASED ON LATEST TRENDS IN RADAR AND MESOSCALE MODEL
DATA. THIS RESULTED IN VERY LITTLE CHANGE TO THE GOING FORECAST.
HEAVIEST SNOW WILL BE FOCUSED ACROSS SOUTHERN AND CENTRAL ZONES
OVER THE NEXT FEW HOURS...AS WELL AS A LOCAL MAX ON THE MID COAST.
LATEST HRRR AND RUC DATA INDICATE A WEAK SECONDARY WAVE AFFECTING
SE NH AND YORK COUNTY MAINE BETWEEN 11Z AND 14Z...SO BUMPED POPS
UP A LITTLE BIT DURING THAT TIME FRAME.
6 PM UPDATE...HAVE UPDATED POPS/QPF/SNOWFALL A LITTLE BIT BASED ON
LATEST TRENDS IN OBSERVATIONAL DATA AS WELL AS THE LATEST
MESOSCALE MODEL GUIDANCE. THIS RESULTED IN NOT MUCH CHANGE...JUST
A SLIGHTLY QUICKER ENDING TIME TO THE SNOW...ESPECIALLY INLAND.
IT ALSO LOWERED SNOW AMOUNTS ABOUT AN INCH ON AVERAGE.
OTHERWISE...THE FORECAST IS ON TRACK.
PREVIOUSLY...
TEMPERATURES HAVE CLIMBED... AS MUCH AS 40 DEGREES IN SOME PLACES
FROM EARLY MORNING LOWS WELL BELOW ZERO TO THE 20S AS
SOUTHWESTERLY FLOW AND WARM AIR ADVECTION KICKED IN AHEAD OF A LOW
PRESSURE SYSTEM.
SNOW WILL MOVE INTO THE REGION THIS AFTERNOON AS AN ELONGATED AREA
OF LOW PRESSURE MOVES FROM THE OHIO RIVER UP TOWARDS THE ST.
LAWRENCE. DESPITE THE LARGE WARM UP IN TEMPERATURES THIS
AFTERNOON, PRECIPITATION IS EXPECTED TO REMAIN SNOW THROUGH THE
OVERNIGHT AS TEMPERATURES ALOFT REMAIN BELOW FREEZING.
TEMPERATURES WILL NOT DROP MUCH OVERNIGHT... REMAINING IN THE 20S
AS SNOW SATURATES THE LOW LEVELS. THE CHANCE FOR MIXED
PRECIPITATION ALONG THE COAST IS DIMINISHING AS COLD AIR SEEMS TO
STAY FURTHER TO THE SOUTH KEEPING ANYTHING FROM MELTING. WARMER
TEMPERATURES WILL MAKE THIS A MUCH DENSER SNOW THAN THE PAST FEW
STORMS... ESPECIALLY ALONG THE COAST.
&&
.SHORT TERM /6 AM SUNDAY MORNING THROUGH 6 PM SUNDAY/...
SUNDAY MORNING PRECIPITATION WILL COME TO AN END FROM WEST TO
EAST AS A COLD FRONT DRAGS THROUGH THE REGION. TEMPERATURES WILL
HOLD STEADY RIGHT NEAR THE FREEZING MARK FOR THE MORNING BEFORE
BRIEFLY SPIKING ABOVE FREEZING FOR THE EARLY PART OF THE
AFTERNOON. THE FIGHT BETWEEN THE END OF THE PRECIPITATION AND THE
ARRIVAL OF THE COLD TEMPERATURES THE IMMEDIATE COAST MAY SEE A
BRIEF CHANGEOVER TO SOME MIXED SLEET OR RAIN... WHICH COULD FREEZE
ON SURFACES. AT THIS POINT FEEL THAT THE PRECIP IS MOST LIKELY TO
END BEFORE AND FREEZING RAIN COULD DEVELOP SO HAVE LEFT ICE
ACCUMULATIONS OUT OF THE FORECAST.
THE COLD FRONT WILL MOVE THROUGH MID DAY ON SUNDAY AND ONCE AGAIN
PUT US INTO COLD AIR ADVECTION AND NORTHWESTERLY FLOW WITH
TEMPERATURES DROPPING STEADILY ALL NIGHT. LOWS WILL BOTTOM OUT
NEAR ZERO IN THE NORTH AND THE LOW TEENS SOUTH.
&&
.LONG TERM /SUNDAY NIGHT THROUGH SATURDAY/...
THE MODELS ARE IN GENERAL AGREEMENT ON THE LONG WAVE PATTERN
INTO NEXT WEEKEND. THE BASIC PATTERN REMAINS AN UPPER RIDGE
CENTERED NEAR OR JUST OFF THE WEST COAST WITH A TROUGH OVER MUCH
OF THE CONUS. THERE`S FAIR AGREEMENT ON SHORTWAVE ENERGY INTO
MID WEEK PERIOD...WHEN CANADIAN HAS A SLOWER AND STRONGER
SOLUTION FOR THE DEVELOPING OCEAN LOW VERSUS THE MORE PROGRESSIVE
ECMWF/GFS SOLUTIONS. HOWEVER...THE 12Z CANADIAN HAS COME MORE IN
LINE WITH THE GFS AND ECMWF SOLUTIONS. WE`LL SEE IF THE MODELS
HOLD ON TO THAT SOLUTION IN THE DAYS AHEAD. OTHERWISE...IT`S
RATHER DRY WITH BELOW NORMAL TEMPERATURES FOR THE WORK WEEK AND
INTO NEXT THE FIRST HALF OF WEEKEND. THE NEXT SYSTEM ARRIVES IN
TIME FOR THE SECOND HALF OF THE WEEKEND. NUMERICALS ARE AT LEAST
HINTING THAT WARMER AIR COULD WORK IN ALOFT...AND PROVIDE A MIXED
BAG OF PRECIPITATION FOR SOUTHERN AND COASTAL SECTIONS.
&&
.AVIATION /04Z SUNDAY THROUGH THURSDAY/...
SHORT TERM...OVERNIGHT PERIODS OF IFR IN HEAVIER SNOW IS
EXPECTED. BOTH CEILINGS AND VISIBILITIES WILL INCREASE TO VFR
AGAIN ON SUNDAY.
LONG TERM...
WED...MVFR PSBL IN SNOW SHOWERS.
&&
.MARINE...
SHORT TERM...SCA FOR THE WATERS THROUGH THE OVERNIGHT AS
SOUTHWESTERLY FLOW INCREASES AHEAD OF THE LOW PASSAGE. WARMING
TEMPERATURES HAVE ELIMINATED THE FREEZING SPRAY THREAT FOR NOW.
LONG TERM...
MON AND WED...GALE FORCE WINDS ARE POSSIBLE.
THU...SMALL CRAFT WINDS AND SEAS ARE POSSIBLE.
&&
.GYX WATCHES/WARNINGS/ADVISORIES...
ME...WINTER WEATHER ADVISORY UNTIL 7 AM EST SUNDAY FOR MEZ012>014-
018>028.
NH...WINTER WEATHER ADVISORY UNTIL 7 AM EST SUNDAY FOR NHZ003>015.
MARINE...GALE WATCH FROM MONDAY MORNING THROUGH LATE MONDAY NIGHT FOR
ANZ150>154.
SMALL CRAFT ADVISORY UNTIL 6 AM EST SUNDAY FOR ANZ150>154.
&&
$$
NEAR TERM...EKSTER
SHORT TERM...CURTIS
LONG TERM...SCHWIBS
AVIATION...SCHWIBS
MARINE...CURTIS/SCHWIBS
AREA FORECAST DISCUSSION
NWS GRAY ME
906 PM EST SAT FEB 21 2015
.SYNOPSIS...
LOW PRESSURE WILL BRING SNOW TO THE AREA TONIGHT. A COLD FRONT
WILL MOVE THROUGH SUNDAY WITH COLD AIR FOR THE START OF THE WEEK.
ARCTIC HIGH PRESSURE WILL BUILD EAST INTO THE AREA MONDAY INTO
TUESDAY. LOW PRESSURE WILL CROSS THE AREA TUESDAY NIGHT INTO
WEDNESDAY. MORE HIGH PRESSURE FOLLOWS THIS SYSTEM FOR THURSDAY
INTO THE START OF NEXT WEEKEND.
&&
.NEAR TERM /UNTIL 6 AM SUNDAY MORNING/...
9 PM UPDATE...HAVE UPDATED POPS AND SNOWFALL AS WELL AS
TEMPERATURES BASED ON LATEST TRENDS IN RADAR AND MESOSCALE MODEL
DATA. THIS RESULTED IN VERY LITTLE CHANGE TO THE GOING FORECAST.
HEAVIEST SNOW WILL BE FOCUSED ACROSS SOUTHERN AND CENTRAL ZONES
OVER THE NEXT FEW HOURS...AS WELL AS A LOCAL MAX ON THE MID COAST.
LATEST HRRR AND RUC DATA INDICATE A WEAK SECONDARY WAVE AFFECTING
SE NH AND YORK COUNTY MAINE BETWEEN 11Z AND 14Z...SO BUMPED POPS
UP A LITTLE BIT DURING THAT TIME FRAME.
6 PM UPDATE...HAVE UPDATED POPS/QPF/SNOWFALL A LITTLE BIT BASED ON
LATEST TRENDS IN OBSERVATIONAL DATA AS WELL AS THE LATEST
MESOSCALE MODEL GUIDANCE. THIS RESULTED IN NOT MUCH CHANGE...JUST
A SLIGHTLY QUICKER ENDING TIME TO THE SNOW...ESPECIALLY INLAND.
IT ALSO LOWERED SNOW AMOUNTS ABOUT AN INCH ON AVERAGE.
OTHERWISE...THE FORECAST IS ON TRACK.
PREVIOUSLY...
TEMPERATURES HAVE CLIMBED... AS MUCH AS 40 DEGREES IN SOME PLACES
FROM EARLY MORNING LOWS WELL BELOW ZERO TO THE 20S AS
SOUTHWESTERLY FLOW AND WARM AIR ADVECTION KICKED IN AHEAD OF A LOW
PRESSURE SYSTEM.
SNOW WILL MOVE INTO THE REGION THIS AFTERNOON AS AN ELONGATED AREA
OF LOW PRESSURE MOVES FROM THE OHIO RIVER UP TOWARDS THE ST.
LAWRENCE. DESPITE THE LARGE WARM UP IN TEMPERATURES THIS
AFTERNOON, PRECIPITATION IS EXPECTED TO REMAIN SNOW THROUGH THE
OVERNIGHT AS TEMPERATURES ALOFT REMAIN BELOW FREEZING.
TEMPERATURES WILL NOT DROP MUCH OVERNIGHT... REMAINING IN THE 20S
AS SNOW SATURATES THE LOW LEVELS. THE CHANCE FOR MIXED
PRECIPITATION ALONG THE COAST IS DIMINISHING AS COLD AIR SEEMS TO
STAY FURTHER TO THE SOUTH KEEPING ANYTHING FROM MELTING. WARMER
TEMPERATURES WILL MAKE THIS A MUCH DENSER SNOW THAN THE PAST FEW
STORMS... ESPECIALLY ALONG THE COAST.
&&
.SHORT TERM /6 AM SUNDAY MORNING THROUGH 6 PM SUNDAY/...
SUNDAY MORNING PRECIPITATION WILL COME TO AN END FROM WEST TO
EAST AS A COLD FRONT DRAGS THROUGH THE REGION. TEMPERATURES WILL
HOLD STEADY RIGHT NEAR THE FREEZING MARK FOR THE MORNING BEFORE
BRIEFLY SPIKING ABOVE FREEZING FOR THE EARLY PART OF THE
AFTERNOON. THE FIGHT BETWEEN THE END OF THE PRECIPITATION AND THE
ARRIVAL OF THE COLD TEMPERATURES THE IMMEDIATE COAST MAY SEE A
BRIEF CHANGEOVER TO SOME MIXED SLEET OR RAIN... WHICH COULD FREEZE
ON SURFACES. AT THIS POINT FEEL THAT THE PRECIP IS MOST LIKELY TO
END BEFORE AND FREEZING RAIN COULD DEVELOP SO HAVE LEFT ICE
ACCUMULATIONS OUT OF THE FORECAST.
THE COLD FRONT WILL MOVE THROUGH MID DAY ON SUNDAY AND ONCE AGAIN
PUT US INTO COLD AIR ADVECTION AND NORTHWESTERLY FLOW WITH
TEMPERATURES DROPPING STEADILY ALL NIGHT. LOWS WILL BOTTOM OUT
NEAR ZERO IN THE NORTH AND THE LOW TEENS SOUTH.
&&
.LONG TERM /SUNDAY NIGHT THROUGH SATURDAY/...
THE MODELS ARE IN GENERAL AGREEMENT ON THE LONG WAVE PATTERN
INTO NEXT WEEKEND. THE BASIC PATTERN REMAINS AN UPPER RIDGE
CENTERED NEAR OR JUST OFF THE WEST COAST WITH A TROUGH OVER MUCH
OF THE CONUS. THERE`S FAIR AGREEMENT ON SHORTWAVE ENERGY INTO
MID WEEK PERIOD...WHEN CANADIAN HAS A SLOWER AND STRONGER
SOLUTION FOR THE DEVELOPING OCEAN LOW VERSUS THE MORE PROGRESSIVE
ECMWF/GFS SOLUTIONS. HOWEVER...THE 12Z CANADIAN HAS COME MORE IN
LINE WITH THE GFS AND ECMWF SOLUTIONS. WE`LL SEE IF THE MODELS
HOLD ON TO THAT SOLUTION IN THE DAYS AHEAD. OTHERWISE...IT`S
RATHER DRY WITH BELOW NORMAL TEMPERATURES FOR THE WORK WEEK AND
INTO NEXT THE FIRST HALF OF WEEKEND. THE NEXT SYSTEM ARRIVES IN
TIME FOR THE SECOND HALF OF THE WEEKEND. NUMERICALS ARE AT LEAST
HINTING THAT WARMER AIR COULD WORK IN ALOFT...AND PROVIDE A MIXED
BAG OF PRECIPITATION FOR SOUTHERN AND COASTAL SECTIONS.
&&
.AVIATION /02Z SUNDAY THROUGH THURSDAY/...
SHORT TERM... CEILINGS WILL DROP TO MVFR FROM WEST TO EAST OVER
THE NEXT FEW HOURS AS SNOW MOVES IN. OVERNIGHT PERIODS OF IFR IN
HEAVIER SNOW IS EXPECTED. BOTH CEILINGS AND VISIBILITIES WILL
INCREASE TO VFR AGAIN ON SUNDAY.
LONG TERM...
WED...MVFR PSBL IN SNOW SHOWERS.
&&
.MARINE...
SHORT TERM...SCA FOR THE WATERS THROUGH THE OVERNIGHT AS
SOUTHWESTERLY FLOW INCREASES AHEAD OF THE LOW PASSAGE. WARMING
TEMPERATURES HAVE ELIMINATED THE FREEZING SPRAY THREAT FOR NOW.
LONG TERM...
MON AND WED...GALE FORCE WINDS ARE POSSIBLE.
THU...SMALL CRAFT WINDS AND SEAS ARE POSSIBLE.
&&
.GYX WATCHES/WARNINGS/ADVISORIES...
ME...WINTER WEATHER ADVISORY UNTIL 7 AM EST SUNDAY FOR MEZ012>014-
018>028.
NH...WINTER WEATHER ADVISORY UNTIL 7 AM EST SUNDAY FOR NHZ003>015.
MARINE...GALE WATCH FROM MONDAY MORNING THROUGH LATE MONDAY NIGHT FOR
ANZ150>154.
SMALL CRAFT ADVISORY UNTIL 6 AM EST SUNDAY FOR ANZ150>154.
&&
$$
NEAR TERM...EKSTER
SHORT TERM...CURTIS
LONG TERM...SCHWIBS
AVIATION...SCHWIBS
MARINE...CURTIS/SCHWIBS
AREA FORECAST DISCUSSION
NWS GAYLORD MI
408 PM EST FRI FEB 20 2015
.NEAR TERM...(THIS EVENING THROUGH TONIGHT)
ISSUED AT 406 PM EST FRI FEB 20 2015
...WIDESPREAD GENERALLY LIGHT SNOW TONIGHT...
HIGH IMPACT WEATHER POTENTIAL: NARROW CORRIDOR OF HEAVIER SNOW
POSSIBLE WEST OF US-31 IN MANISTEE AND BENZIE COUNTIES AND OVER
PARTS OF FAR WESTERN MACKINAC COUNTY...OTHERWISE GENERALLY LIGHT
SNOW ACCUMULATIONS OVER THE REMAINDER OF THE AREA.
PRIMARY FORECAST CHALLENGES/CONCERNS: HOW FAR INLAND WILL ENHANCED
HEAVIER SNOW BAND OVER LAKE MICHIGAN GET INTO COASTAL AREAS.
DETAILS: ISENTROPIC UPGLIDE /285-270K SFC/ INCREASING ACROSS
NORTHERN MICHIGAN IN ADVANCE OF SHORTWAVE TROF OVER MN/NRN WI. TOP
DOWN SATURATION GRADUALLY YIELDING LIGHT SNOW OVER FAR WESTERN
PORTIONS OF THE AREA. LIGHT SNOW WILL OVERSPREAD THE ENTIRE AREA BY
EARLY THIS EVENING...WITH A 6 HOUR WINDOW OF FAVORABLE DYNAMICS
/ALBEIT SOMEWHAT LIMITED MOISTURE/. NOT THE MOST FAVORABLE CLOUD
MICROPHYSICS WITH BEST OMEGA NOT SQUARELY FOCUSED WITHIN THE DGZ FOR
MUCH OF THE SNOWFALL PERIOD. TRANSITORY NATURE OF THE SHORTWAVE
COMBINED WITH MID LEVEL MIXING RATIO/S ON THE ORDER OF 1-2 G/KG
POINT TOWARD A GENERAL 1-2 INCH SNOWFALL FOR MOST LOCATIONS.
THE EXCEPTION TO THIS IS OVER PARTS OF MANISTEE...BENZIE AND
MACKINAC COUNTIES...WHERE NORTH-SOUTH ORIENTED CONVERGENCE AREA
UP THE SPINE OF LAKE MICHIGAN WILL CREATE POCKETS OF HEAVIER SNOW.
HIGH RESOLUTION HRRR GUIDANCE SHOWS THIS ENHANCED LAKE MICHIGAN BAND
QUITE WELL...KEEPING IT NEAR/ALONG THE LAKE MICHIGAN COAST THIS
EVENING...POSSIBLY NOSING IT INTO FAR WESTERN MACKINAC COUNTY.
AFTER COLLABORATION WITH THE GRAND RAPIDS NWS OFFICE AND WITH THE
POTENTIAL FOR SOME LOCALIZED 3-5 INCH SNOWFALL AMOUNTS IN THE
WESTERN PARTS OF BENZIE-MANISTEE COUNTIES...WENT AHEAD AND ISSUED A
WINTER WEATHER ADVISORY THROUGH 7 AM SATURDAY. NO ADVISORY FOR
MACKINAC COUNTY...AS BEST CONVERGENCE REMAINS SOUTH OF THAT AREA AND
ENHANCED SNOWFALL POTENTIAL WOULD LIKELY ONLY IMPACT A SMALL PORTION
OF THE COUNTY /FAR WESTERN AREAS/.
WIDESPREAD SNOW ENDS FROM WEST-EAST AFTER MIDNIGHT AS THE SHORTWAVE
PULLS EAST AND BEST DYNAMICS DIMINISH. A MUCH "WARMER" NIGHT IN
STORE FOR THE AREA COMPARED TO LAST NIGHT /WHICH ISN`T EXACTLY
SAYING MUCH/ WITH LOW TEMPERATURES GENERALLY IN THE SINGLE DIGITS
ABOVE ZERO.
&&
.SHORT TERM...(SATURDAY THROUGH MONDAY)
ISSUED AT 406 PM EST FRI FEB 20 2015
HIGH IMPACT WEATHER POTENTIAL: ANOTHER COLD WAVE SUNDAY
NIGHT/MONDAY MORNING, BUT NOT AS COLD AS THIS MORNING.
FORECAST CHALLENGES: LES IMPACTS WITH MOST OF THE GREAT LAKES
COVERED AND LOW TEMPERATURES AS THE NEXT COLD WAVE MOVE INTO THE
UPPER GREAT LAKES SUNDAY/MONDAY.
(2/21)SATURDAY...AROUND 12Z, THE COLD FRONT BEGINS TO MOVE THROUGH
THE REGION. THE SOUTHWEST WINDS SHOULD BE TURNING WEST BY 12Z,
LEADING TO A SHORT PERIOD OF WESTERLY FETCH FOR THE LAKE SNOW. THE
ONLY ISSUE WITH ANY LES IS THE N LAKE MICHIGAN HAS LITTLE OPEN
WATER, AND MOST OF THE THAT IS SOUTH OF THE MANITOU ISLANDS. WIND
DIRECTIONS GIVE LIMITED FETCH AS THEY GET INTO N LOWER, AND EVEN E
UPPER. SO HAVE SCALED BACK THE POPS A BIT AS THE OVERALL AREA WILL
HAVE A LIGHT CLIPPER SNOW, WITH LITTLE ADDED LES ON THE BACK END.
WINDS AFTER 18Z BECOME MORE NW AND NNW SO MAY GET SOME MINOR SNOW
AND FLURRIES NORTH OF M-32 AS THE STREAM LINES POINT TO LITTLE TO
NOTHING HAPPENING AS THE ATMOSPHERE DRIES OUT AS WELL BY THE EARLY
EVENING.
SATURDAY NIGHT...THE 850-700 MB LAYER RH FALL TO AROUND 40% BY 00Z
AND WITH THE 850 MB TEMPERATURES OF -20C (AT 0Z)CROSSING THE ICE,
THE LES WILL BE ALMOST NON-EXISTENT THROUGH MOST OF THE NIGHT. 850
MB TEMPERATURES CONTINUE TO COOL TO AROUND -30C IN LAKE SUPERIOR,
PROVIDING SOME INSTABILITY, WITH THE MOISTURE AT 850-700 MB LAYER
INCREASING TO AROUND 80% SOME LES WOULD BE POSSIBLE, BUT LACK OF
OPEN WATER WILL BE DIFFICULT TO GET MUCH GOING.
(2/22)SUNDAY...THE AIR MASS LOOKS COLD OVERNIGHT INTO SUNDAY
MORNING, BUT THE MAIN PROBLEM IS THAT CLOUDS ARE EXPECTED TO MOVE
INTO THE REGION BY 12Z, WHICH WILL PROBABLY INHIBIT THE TEMPERATURES
FROM FALLING MUCH BELOW -20F. HOWEVER, CONSIDERING THE MODELS`
ABILITY TO GET THE CLOUDS RIGHT, WOULD NOT BE SURPRISED IF THE LOW
TEMPERATURES IN THE MORNING WILL BE COLDER THAN WE HAVE. THINK THAT
THE LOWER TEENS BELOW ZERO IDEA IS THE BEST IDEA FOR NOW, UNTIL THE
LIGHT SNOW GETS STARTED BY 18Z, MAYBE SOONER IF THE CLOUDS ENCROACH
AND THE INSTABILITY CAN GET ENOUGH MOISTURE TO PRODUCE SNOW. MINOR
SNOW ACCUMULATIONS ARE EXPECTED TO THROUGH 00Z. THE FLOW AND
MOISTURE IS EXPECTED TO CONTINUE OVERNIGHT.
(2/23)MONDAY...THE MORNING MAY TURN OUT DRY, BUT FOR NOW WILL
CONTINUE THE LIGHT SNOW CHANCE, AS THE EXTREME COLD AIR AND
RETREATING MOISTURE MAY PRODUCE MINOR ACCUMULATIONS. BY 18Z, THE
WINDS TURN WSW, SO THAT THERE COULD BE SOME LES IN THE EVENING JUST
BEFORE THE NEXT SYSTEM MOVES INTO THE UPPER GREAT LAKES.
&&
.LONG TERM...(MONDAY NIGHT THROUGH FRIDAY)
ISSUED AT 406 PM EST FRI FEB 20 2015
CONTINUED COLD WITH PERIODS OF SNOW. A COLD FRONT ASSOCIATED WITH A
LOW PRESSURE SYSTEM NEAR JAMES BAY WILL EXTEND THROUGH
MICHIGAN...POSSIBLY PRODUCING SOME ACCUMULATING SNOWS THROUGHOUT THE
BEGINNING OF THE PERIOD AND MODERATING TEMPERATURES INTO THE 20S ON
SOUTHERLY WINDS AHEAD OF THIS COLD FRONT. A LARGE AREA OF HIGH
PRESSURE WILL BUILD IN BEHIND THIS DEPARTING SYSTEM AND DOMINATE
THROUGH THE REMAINING PERIOD...CONTINUING THE COLD TEMPERATURES
WHICH ARE FAR BELOW NORMAL FOR THIS TIME OF THE YEAR. WITH THE
ABNORMALLY COLD TEMPERATURES WILL ALSO COME THE CHANCES OF NUISANCE
LAKE CLOUDS AND SOME LAKE EFFECT SNOW SHOWERS WHERE OPEN WATERS
STILL REMAIN OVER PORTIONS OF LAKE MICHIGAN AND LAKE SUPERIOR.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON)
ISSUED AT 1222 PM EST FRI FEB 20 2015
HIGH CONFIDENCE IN -SN AND IFR CONDITIONS DEVELOPING THIS
AFTERNOON/EVENING.
EXPECT -SN TO DEVELOP AT MBL/TVC/PLN THIS AFTERNOON...APN IN THE
EVENING. CIGS LOWERING TO MVFR...WITH IFR VSBYS LATE THIS
AFTERNOON AND EVENING. VSBYS WILL IMPROVE LATE TONIGHT INTO
SATURDAY AS SNOW EXITS EAST OF THE REGION. SCATTERED -SHSN
CONTINUING SATURDAY MORNING...ESPECIALLY AT MBL/TVC/PLN.
LLWS THIS EVENING AT MBL/TVC...WITH STRONGER SSW FLOW JUST OFF
THE DECK.
&&
.APX WATCHES/WARNINGS/ADVISORIES...
MI...WINTER WEATHER ADVISORY UNTIL 7 AM EST SATURDAY FOR MIZ025-031.
LH...NONE.
LM...NONE.
LS...NONE.
&&
$$
NEAR TERM...KEYSOR
SHORT TERM...JSL
LONG TERM...TJL
AVIATION...KEYSOR
AREA FORECAST DISCUSSION...CORRECTED
NWS GRAND RAPIDS MI
333 PM EST FRI FEB 20 2015
LATEST UPDATE...
SYNOPSIS/SHORT TERM/LONG TERM/HYDRO
.SYNOPSIS...
ISSUED AT 333 PM EST FRI FEB 20 2015
AN APPROACHING ARCTIC COLD FRONT WILL SPREAD MOSTLY LIGHT SNOW
ACROSS THE AREA THIS AFTERNOON AND TONIGHT. LOCALIZED HEAVIER SNOW
IS EXPECTED AT THE LAKESHORE NORTH OF THE MUSKEGON AREA. THE SNOW
WILL LINGER SATURDAY AS ANOTHER LOW MOVES NORTHEAST ACROSS THE OHIO
VALLEY. LOCATIONS AROUND AND SOUTH OF I-94 COULD SEE UP TO A COUPLE
INCHES OF ADDITIONAL SNOW SATURDAY. ANOTHER CLIPPER LOW COULD BRING
SNOWY AND WINDY CONDITIONS ACROSS THE AREA TUESDAY COULD IMPACT
TRAVEL. OTHERWISE...LAKE EFFECT SNOW SHOWERS WILL BE VERY COMMON
THROUGH THE COMING WEEK.
THERE WILL BE A VERY BRIEF WARMUP WITH HIGH TEMPERATURES APPROACHING
30 ON SATURDAY. THEN COLD RETURNS IN FORCE SATURDAY NIGHT WITH HIGHS
GENERALLY IN THE TEENS AND LOWS IN THE SINGLE DIGITS OR BELOW ZERO
FOR THE REST OF THE COMING WORK WEEK.
&&
.SHORT TERM...(THIS EVENING THROUGH SUNDAY NIGHT)
ISSUED AT 333 PM EST FRI FEB 20 2015
INCREASED FORECAST SNOW AMOUNTS TONIGHT ALONG THE LAKESHORE NORTH OF
WHITEHALL AND HOISTED AN ADVISORY. LUDINGTON VISIBILITIES ALREADY
HAVE BEEN AT OR BELOW HALF A MILE IN SNOW AND WE EXPECT THAT AREA
COULD EASILY SEE 5 INCHES OR MORE TOTAL ACCUMULATIONS OVERNIGHT.
CURRENT SURFACE OBSERVATIONS SHOW A SIGNIFICANT OFFSHORE COMPONENT
TO THE WINDS OVER OUR NORTHERN LAKESHORE AREA. HRRR GUIDANCE
INDICATES A STRENGTHENING CONVERGENCE ZONE PARALLEL TO AND BARELY
OFF THE LAKESHORE EARLY TONIGHT THAT SHOULD FOCUS BRIEFLY INTENSE
SNOWFALL RATES. THIS CONVERGENCE AREA AND ASSOCIATED SNOWFALL
SHOULD PUSH INLAND BY AROUND MIDNIGHT. ALTHOUGH THE ADVISORY IS
SET TO EXPIRE AT 7 AM SATURDAY...COULD EASILY SEE SNOWFALL RATES
DECREASING SIGNIFICANTLY AFTER MIDNIGHT.
WITH THIS UPPER TROUGH IS A DEVELOPING SURFACE LOW THAT TRACKS
NORTHEAST ACROSS THE OHIO VALLEY. WE ARE FAIRLY CERTAIN THAT IMPACTS
WITH THIS SHOULD BE MINIMAL WITH PERHAPS A COUPLE INCHES
ACCUMULATION NEAR JACKSON DURING THE DAY SATURDAY.
SATURDAY NIGHT AND SUNDAY SHOULD SEE PERSISTENT LAKE EFFECT WITH 850
MB TEMPERATURES DROPPING TOWARDS -25C. LIMITED MOISTURE AND
SUB-OPTIMAL MICROPHYSICS SHOULD LIMIT ADDITIONAL ACCUMULATIONS TO
AROUND A COUPLE INCHES NEAR THE LAKESHORE.
.LONG TERM...(MONDAY THROUGH FRIDAY)
ISSUED AT 333 PM EST FRI FEB 20 2015
NO SIGNIFICANT CHANGES TO LONG TERM FORECAST...STRONG CLIPPER COULD
BRING 35MPH+ WIND GUSTS ON TUESDAY WITH SNOW SQUALLS TUESDAY
NIGHT INTO WEDNESDAY. ANOTHER ARCTIC AIRMASS WILL KEEP TEMPERATURES
WELL BELOW NORMAL FOR THE END OF THE WEEK.
LATEST 12Z GUIDANCE REMAINS IN VERY GOOD AGREEMENT ON EVOLUTION OF
WEATHER PATTERN OVER THE NEXT WEEK. BASICALLY A CONTINUATION OF THE
CURRENT WEATHER WITH THE ANOMALOUS WEST COAST RIDGE AND DOWN STREAM
TROUGH CENTERED OVER GREAT LAKES. THERE IS HOWEVER SOME CHANCE OF A
TEMPORARY BREAKDOWN OF THIS PATTERN NEXT WEEKEND WHICH WOULD LEAD TO
NEAR NORMAL TEMPERATURES FOR THE END OF FEBRUARY.
OUR EVENTUAL MID-WEEK CLIPPER IS PRESENTLY NORTH OF BARROW...ALASKA.
IT IS FORECAST TO DIG SOUTHEASTWARD THROUGH WESTERN CANADA REACHING
THE UPPER GREAT LAKES ON TUESDAY WITH AN ALMOST CLOSED H500 LOW BY
WEDNESDAY. ALONG WITH IT COMES A SHOT OF SIBERIAN ARCTIC AIR.
THIS WOULD NORMALLY BE A GOOD SETUP FOR A SIGNIFICANT LAKE
ENHANCED EVENT...BUT HAVE A COUPLE OF CONCERNS. THE FIRST IS THE
THAT THE WAVE IS PRESENTLY IN A DATA SPARSE AREA OBSERVATION
WISE...SO WHILE THE TREND HAS BEEN STABLE AT PRESENT...WOULD NOT
BE SURPRISED BY A JUMP OR TWO IN THE FORECAST OVER THE NEXT COUPLE
OF DAYS. SECONDLY...LAKE MICHIGAN IS REALLY STARTING TO SLUSH UP
AND THAT WILL BEGIN TO LIMIT THE ABILITY OF THE LAKE TO ENHANCE
THE SYSTEM SNOWFALL. STAY TUNED...
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON)
ISSUED AT 111 PM EST FRI FEB 20 2015
NO SIGNIFICANT CHANGES TO CURRENT FORECAST...EXPECTING A PERIOD OF
1-3 MILE VSBY IFR SNOW TO MOVE THROUGH THE REGION TONIGHT WITH
SOME LAKE ENHANCED SNOW KMKG TO KLDM. ALSO SOME MAINLY LIGHT
TURBULENCE BELOW 030KFT THROUGH THIS EVENING.
MAINLY VFR/MVFR CONDITIONS EXPECTED ON SATURDAY WITH SCT IFR SNOW
SHOWER ACTIVITY ASSOCIATED WITH PASSAGE OF NEXT ARCTIC COLD
FRONT BY SAT EVE.
OUTLOOK...IFR LAKE EFFECT SNOW SHOWERS WEST OF KRQB - KGRR - KBTL
LINE ON SUNDAY WITH VFR/MVFR FLURRIES TO THE EAST WITH ANOTHER
SHOT OF ARCTIC AIR.
&&
.HYDROLOGY...
ISSUED AT 308 PM EST FRI FEB 20 2015
FAIRLY STEADY RIVER LEVELS ARE EXPECTED ACROSS THE AREA... WITH NO
SITES NEAR BANKFULL. TEMPERATURES WILL ONLY APPROACH FREEZING ON
SATURDAY WITH VALUES BELOW 20 DEGREES MOST OF THE WEEK. THIS SHOULD
RESULT IN THE ICE ON AREA RIVERS AND THE WATER IN THE SNOWPACK
REMAINING LOCKED UP. CURRENTLY... THERE ARE NO SUSPECTED ICE JAMS IN
THE AREA. SERIOUS ICE JAMS AND FLOODING CONCERNS ARE UNLIKELY UNTIL
A SIGNIFICANT WARM UP AND RAINFALL OCCUR.
&&
.GRR WATCHES/WARNINGS/ADVISORIES...
MI...WINTER WEATHER ADVISORY UNTIL 7 AM EST SATURDAY FOR MIZ037-043-
050.
LM...NONE.
&&
$$
SYNOPSIS...TJT
SHORT TERM...TJT
LONG TERM...COBB
AVIATION...COBB
HYDROLOGY...63
AREA FORECAST DISCUSSION
NWS GRAND RAPIDS MI
315 PM EST FRI FEB 20 2015
LATEST UPDATE...
SYNOPSIS/SHORT TERM/LONG TERM/HYDRO
.SYNOPSIS...
ISSUED AT 308 PM EST FRI FEB 20 2015
AN APPROACHING ARCTIC COLD FRONT WILL SPREAD MOSTLY LIGHT SNOW
ACROSS THE AREA THIS AFTERNOON AND TONIGHT. LOCALIZED HEAVIER SNOW
IS EXPECTED AT THE LAKESHORE NORTH OF THE MUSKEGON AREA. THE SNOW
WILL LINGER SATURDAY AS ANOTHER LOW MOVES NORTHEAST ACROSS THE OHIO
VALLEY. LOCATIONS AROUND AND SOUTH OF I-94 COULD SEE UP TO A COUPLE
INCHES OF ADDITIONAL SNOW SATURDAY. SNOWY AND WINDY CONDITIONS
ACROSS THE AREA TUESDAY COULD IMPACT TRAVEL. OTHERWISE...LAKE EFFECT
SNOW SHOWERS WILL BE VERY COMMON THROUGH THE COMING WEEK.
THERE WILL BE A VERY BRIEF WARMUP WITH HIGH TEMPERATURES APPROACHING
30 ON SATURDAY. THEN COLD RETURNS IN FORCE SATURDAY NIGHT WITH HIGHS
GENERALLY IN THE TEENS AND LOWS IN THE SINGLE DIGITS OR BELOW ZERO
FOR THE REST OF THE COMING WORK WEEK.
&&
.SHORT TERM...(THIS EVENING THROUGH SUNDAY NIGHT)
ISSUED AT 308 PM EST FRI FEB 20 2015
INCREASED FORECAST SNOW AMOUNTS TONIGHT ALONG THE LAKESHORE NORTH OF
WHITEHALL AND HOISTED AN ADVISORY. LUDINGTON VISIBILITIES ALREADY
HAVE BEEN AT OR BELOW HALF A MILE IN SNOW AND WE EXPECT THAT AREA
COULD EASILY SEE 5 INCHES OR MORE TOTAL ACCUMULATIONS OVERNIGHT.
CURRENT SURFACE OBSERVATIONS SHOW A SIGNIFICANT OFFSHORE COMPONENT
TO THE WINDS OVER OUR NORTHERN LAKESHORE AREA. HRRR GUIDANCE
INDICATES A STRENGTHENING CONVERGENCE ZONE PARALLEL TO AND BARELY
OFF THE LAKESHORE EARLY TONIGHT THAT SHOULD FOCUS BRIEFLY INTENSE
SNOWFALL RATES. THIS CONVERGENCE AREA AND ASSOCIATED SNOWFALL
SHOULD PUSH INLAND BY AROUND MIDNIGHT. ALTHOUGH THE ADVISORY IS
SET TO EXPIRE AT 7 AM SATURDAY...COULD EASILY SEE SNOWFALL RATES
DECREASING SIGNIFICANTLY AFTER MIDNIGHT.
WITH THIS UPPER TROUGH IS A DEVELOPING SURFACE LOW WE HAVE BEEN
WATCHING THAT TRACKS NORTHEAST ACROSS THE OHIO VALLEY. WE ARE FAIRLY
CERTAIN THAT IMPACTS WITH THIS SHOULD BE MINIMAL WITH PERHAPS A
COUPLE INCHES ACCUMULATION NEAR JACKSON DURING THE DAY SATURDAY.
SATURDAY NIGHT AND SUNDAY SHOULD SEE PERSISTENT LAKE EFFECT WITH 850
MB TEMPERATURES DROPPING TOWARDS -25C. LIMITED MOISTURE AND
SUB-OPTIMAL MICROPHYSICS SHOULD LIMIT ADDITIONAL ACCUMULATIONS TO
AROUND A COUPLE INCHES NEAR THE LAKESHORE.
.LONG TERM...(MONDAY THROUGH FRIDAY)
ISSUED AT 308 PM EST FRI FEB 20 2015
NO SIGNIFICANT CHANGES TO LONG TERM FORECAST...STRONG CLIPPER COULD
BRING 35MPH+ WIND GUSTS ON TUESDAY WITH SNOW SQUALLS TUESDAY
NIGHT INTO WEDNESDAY. ANOTHER ARCTIC AIRMASS WILL KEEP TEMPERATURES
WELL BELOW NORMAL FOR THE END OF THE WEEK.
LATEST 12Z GUIDANCE REMAINS IN VERY GOOD AGREEMENT ON EVOLUTION OF
WEATHER PATTERN OVER THE NEXT WEEK. BASICALLY A CONTINUATION OF THE
CURRENT WEATHER WITH THE ANOMALOUS WEST COAST RIDGE AND DOWN STREAM
TROUGH CENTERED OVER GREAT LAKES. THERE IS HOWEVER SOME CHANCE OF AT
LEAST A TEMPORARY BREAKDOWN OF THIS PATTERN NEXT WEEKEND WHICH WOULD
LEAD TO AT LEAST NEAR NORMAL TEMPERATURES FOR THE END OF FEBRUARY.
OUR EVENTUAL MID-WEEK CLIPPER IS PRESENTLY NORTH OF BARROW...ALASKA.
IT IS FORECAST TO DIG SOUTHEASTWARD THROUGH WESTERN CANADA REACHING
THE UPPER GREAT LAKES ON TUESDAY WITH AN ALMOST CLOSED H500 LOW BY
WEDNESDAY. ALONG WITH IT COMES A SHOT OF SIBERIAN ARCTIC AIR.
THIS WOULD NORMALLY BE A GOOD SETUP FOR A SIGNIFICANT LAKE
ENHANCED EVENT...BUT HAVE A COUPLE OF CONCERNS. THE FIRST IS THE
THAT THE WAVE IS PRESENTLY IN A DATA SPARSE AREA OBSERVATION
WISE...SO WHILE THE TREND HAS BEEN STABLE AT PRESENT...WOULD NOT
BE SURPRISED BY A JUMP OR TWO IN THE FORECAST OVER THE NEXT COUPLE
OF DAYS. SECONDLY...LAKE MICHIGAN IS REALLY STARTING TO SLUSH UP
AND THAT WILL BEGIN TO LIMIT THE ABILITY OF THE LAKE TO ENHANCE
THE SYSTEM SNOWFALL. STAY TUNED...
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON)
ISSUED AT 111 PM EST FRI FEB 20 2015
NO SIGNIFICANT CHANGES TO CURRENT FORECAST...EXPECTING A PERIOD OF
1-3 MILE VSBY IFR SNOW TO MOVE THROUGH THE REGION TONIGHT WITH
SOME LAKE ENHANCED SNOW KMKG TO KLDM. ALSO SOME MAINLY LIGHT
TURBULENCE BELOW 030KFT THROUGH THIS EVENING.
MAINLY VFR/MVFR CONDITIONS EXPECTED ON SATURDAY WITH SCT IFR SNOW
SHOWER ACTIVITY ASSOCIATED WITH PASSAGE OF NEXT ARCTIC COLD
FRONT BY SAT EVE.
OUTLOOK...IFR LAKE EFFECT SNOW SHOWERS WEST OF KRQB - KGRR - KBTL
LINE ON SUNDAY WITH VFR/MVFR FLURRIES TO THE EAST WITH ANOTHER
SHOT OF ARCTIC AIR.
&&
.HYDROLOGY...
ISSUED AT 308 PM EST FRI FEB 20 2015
FAIRLY STEADY RIVER LEVELS ARE EXPECTED ACROSS THE AREA... WITH NO
SITES NEAR BANKFULL. TEMPERATURES WILL ONLY APPROACH FREEZING ON
SATURDAY WITH VALUES BELOW 20 DEGREES MOST OF THE WEEK. THIS SHOULD
RESULT IN THE ICE ON AREA RIVERS AND THE WATER IN THE SNOWPACK
REMAINING LOCKED UP. CURRENTLY... THERE ARE NO SUSPECTED ICE JAMS IN
THE AREA. SERIOUS ICE JAMS AND FLOODING CONCERNS ARE UNLIKELY UNTIL
A SIGNIFICANT WARM UP AND RAINFALL OCCUR.
&&
.GRR WATCHES/WARNINGS/ADVISORIES...
MI...WINTER WEATHER ADVISORY UNTIL 7 AM EST SATURDAY FOR MIZ037-043-
050.
LM...NONE.
&&
$$
SYNOPSIS...TJT
SHORT TERM...TJT
LONG TERM...COBB
AVIATION...COBB
HYDROLOGY...63
AREA FORECAST DISCUSSION
NWS GRAND RAPIDS MI
128 PM EST FRI FEB 20 2015
LATEST UPDATE...
SHORT TERM
.SYNOPSIS...
ISSUED AT 328 AM EST FRI FEB 20 2015
A CLIPPER WILL APPROACH LOWER MICHIGAN LATER TODAY AND SPREAD LIGHT
SNOW ACROSS IT LATE THIS AFTERNOON AND TONIGHT. A COUPLE OF INCHES
OF SNOW IS POSSIBLE WEST OF US-131 AND AROUND AN INCH EAST OF THERE.
THE SNOW WILL LINGER INTO SATURDAY AS ANOTHER LOW MOVES OVER THE
OHIO VALLEY. LOCATIONS SOUTH OF I-94 COULD SEE UP TO AN INCH OF SNOW
SATURDAY FROM THAT SYSTEM.
TEMPERATURES WILL BE WELL BELOW NORMAL TODAY WITH HIGHS IN THE
TEENS. HOWEVER TEMPERATURES WILL WARM UP SATURDAY AND APPROACH 30.
BEHIND THE CLIPPER SUNDAY TEMPERATURES WILL REMAIN MOSTLY IN THE
TEENS. IN FACT MUCH OF NEXT WEEK WILL SEE HIGHS IN THE TEENS.
&&
.SHORT TERM...(THIS EVENING THROUGH SATURDAY)
ISSUED AT 128 PM EST FRI FEB 20 2015
HAVE INCREASED FORECAST SNOW AMOUNTS TONIGHT ALONG THE LAKESHORE
NORTH OF WHITEHALL AND HAVE HOISTED AN ADVISORY. LUDINGTON
VISIBILITIES ARE ALREADY DOWN TO HALF A MILE IN SNOW AND THAT AREA
COULD EASILY SEE 5 INCHES OR MORE TOTAL ACCUMULATION OVERNIGHT.
CURRENT SURFACE OBSERVATIONS SHOW A SIGNIFICANT OFFSHORE COMPONENT
TO THE WINDS OVER OUR NORTHERN LAKESHORE AREA. HRRR GUIDANCE
INDICATES A STRENGTHENING CONVERGENCE ZONE PARALLEL TO AND BARELY
OFF THE LAKESHORE EARLY TONIGHT THAT SHOULD FOCUS BRIEFLY INTENSE
SNOWFALL RATES. THIS CONVERGENCE AREA AND ASSOCIATED SNOWFALL
SHOULD PUSH INLAND BY AROUND MIDNIGHT. ALTHOUGH THE ADVISORY IS
SET TO EXPIRE AT 7 AM SATURDAY...COULD EASILY SEE SNOWFALL RATES
DECREASING SIGNIFICANTLY AFTER MIDNIGHT.
THIS LOCALIZED FORCING WILL OCCUR AGAINST A BACKDROP OF LARGER SCALE
FORCING AS AN UPPER TROUGH DEVELOPS UPSTREAM. THIS SHOULD BE
SUFFICIENT FOR ACCUMULATIONS ACROSS THE ENTIRE FORECAST AREA.
WITH THIS UPPER TROUGH IS A DEVELOPING SURFACE LOW WE HAVE BEEN
WATCHING THAT TRACKS NORTHEAST ACROSS THE OHIO VALLEY. WE ARE FAIRLY
CERTAIN THAT IMPACTS WITH THIS SHOULD BE MINIMAL WITH PERHAPS A
COUPLE INCHES ACCUMULATION NEAR JACKSON DURING THE DAY SATURDAY.
.LONG TERM...(SUNDAY NIGHT THROUGH THURSDAY)
ISSUED AT 328 AM EST FRI FEB 20 2015
THE MOST SIGNIFICANT IMPACTS THIS COMING WEEK WILL BE WITH THE SNOW
SHOWERS...STRONG WIND AND COLD TEMPERATURES ASSOCIATED WITH THE NEXT
CLIPPER SYSTEM AS IT MOVES THROUGH THE AREA TUESDAY INTO WEDNESDAY.
ONCE THE CLIPPER MOVES THROUGH THE AREA WE WILL THEN BE WATCHING THE
LAKE ENHANCED SNOW SHOWERS WITH WIND CHILL ISSUES LATER WEDNESDAY
THROUGH THURSDAY.
THE LONG WAVE PATTERN REMAINS STABLE THROUGH THIS COMING WEEK WITH A
RIDGE OVER THE WESTERN UNITED STATES AND OFF THE WEST COAST OVER THE
EASTERN PACIFIC WITH A DOWNSTREAM TROUGH OVER THE EASTERN UNITED
STATES AND CANADA. THERE IS NO SIGN OF THIS BRAKING UP IN AT LEAST
THE NEXT WEEK OR SO. MEANING THE COLD WEATHER PATTERN WE CURRENTLY
HAVE WILL CONTINUE THROUGH THIS COMING WEEK.
A SERIES OF NORTHERN STREAM SHORTWAVES CONTINUES TO DIVE SOUTH
SOUTHEAST FROM THE ARCTIC INTO THE GREAT LAKES AREA THROUGH NEXT
WEEK. A WEAKER SYSTEM MOVES THROUGH THE AREA SUNDAY NIGHT INTO
MONDAY WITH LAKE ENHANCED SNOW SHOWERS (MOISTURE IS NOT VERY DEEP
BUT THERE IS ENOUGH TO ALLOW LAKE EFFECT SNOW SHOWERS). A MUCH
STRONGER SYSTEM FOLLOWS FOR TUESDAY INTO WEDNESDAY. THE ECMWF SHOWS
MORE DIGGING WITH THIS SYSTEM AN SINCE THAT IS THE TYPICAL MODEL
ERROR OF THE GFS (TO WEAK WITH NORTHERN STREAM SHORTWAVES) LIKELY
THE ECMWF WILL BE THE MORE CORRECT SOLUTION. THERE IS ANOTHER UPPER
LEVEL WAVE THAT TRAILS THIS SYSTEM FOR THURSDAY TO KEEP THE LAKE
EFFECT SNOW GOING AND BRING DOWN ANOTHER PERIOD OF 850 MB TEMPS
BELOW -20C (THAT KEEPS HIGHS HERE IN THE TEENS OR COLDER).
AS NOTED BY THE PREVIOUS SHIFT THE STRENGTH AND AMOUNT OF DIGGING OF
THE NORTHERN STREAM SHORTWAVE IS THE KEY TO HOW BIG AN EVENT THIS
WILL TURN OUT TO BE. NO MATTER WHICH IS CORRECT THERE WILL STILL BE
STRONG SOUTHWEST WINDS AHEAD OF THE SYSTEM WITH LAKE ENHANCED SNOW
TO OUR WEST AND NORTHWEST CWA. SOME BLOWING AND DRIFTING SNOW
TUESDAY AFTERNOON AND EVENING IS EXPECTED DUE TO THE STRONG WINDS.
THEN AS THE SYSTEM MOVES THROUGH WITH THE ASSOCIATED ARCTIC FRONT
NORTHWEST FLOW LAKE EFFECT SNOW SHOWERS WILL FOLLOW INTO AT LEAST
THURSDAY. LIKE THIS PAST EVENT LOW WIND CHILLS MAY BE AN ISSUE LATER
WEDNESDAY INTO THURSDAY.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON)
ISSUED AT 111 PM EST FRI FEB 20 2015
NO SIGNIFICANT CHANGES TO CURRENT FORECAST...EXPECTING A PERIOD OF
1-3 MILE VSBY IFR SNOW TO MOVE THROUGH THE REGION TONIGHT WITH
SOME LAKE ENHANCED SNOW KMKG TO KLDM. ALSO SOME MAINLY LIGHT
TURBULENCE BELOW 030KFT THROUGH THIS EVENING.
MAINLY VFR/MVFR CONDITIONS EXPECTED ON SATURDAY WITH SCT IFR SNOW
SHOWER ACTIVITY ASSOCIATED WITH PASSAGE OF NEXT ARCTIC COLD
FRONT BY SAT EVE.
OUTLOOK...IFR LAKE EFFECT SNOW SHOWERS WEST OF KRQB - KGRR - KBTL
LINE ON SUNDAY WITH VFR/MVFR FLURRIES TO THE EAST WITH ANOTHER
SHOT OF ARCTIC AIR.
&&
.HYDROLOGY...
ISSUED AT 328 PM EST THU FEB 19 2015
FAIRLY STEADY RIVER LEVELS ARE EXPECTED ACROSS THE AREA... WITH NO
SITES NEAR BANKFULL. TEMPERATURES WILL ONLY APPROACH FREEZING ON
SATURDAY WITH VALUES BELOW 20 DEGREES MOST OF THE WEEK. THIS SHOULD
RESULT IN THE ICE ON AREA RIVERS AND THE WATER IN THE SNOWPACK
REMAINING LOCKED UP. CURRENTLY... THERE ARE NO SUSPECTED ICE JAMS IN
THE AREA.
&&
.GRR WATCHES/WARNINGS/ADVISORIES...
MI...WINTER WEATHER ADVISORY UNTIL 7 AM EST SATURDAY FOR MIZ037-043-
050.
LM...NONE.
&&
$$
SYNOPSIS...04
SHORT TERM...TJT
LONG TERM...WDM
AVIATION...COBB
HYDROLOGY...63
AREA FORECAST DISCUSSION
NWS TWIN CITIES/CHANHASSEN MN
554 AM CST FRI FEB 20 2015
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 423 AM CST FRI FEB 20 2015
TODAY WILL BE THE ODD WARM DAY IN AN OTHERWISE COLD PATTERN AS WE
GET INTO THE WARM SECTOR OF A CLIPPER THAT WAS OVER NE NODAK AT 330
THIS MORNING. THIS CLIPPER WILL SCOOT ACROSS THE INTERNATIONAL
BORDER TODAY...WITH A BRIEF HIT OF MILDER AIR MOVING THROUGH TODAY
OUT AHEAD OF THE NEXT ARCTIC COLD FRONT...WHICH WILL QUICKLY MOVE
BACK ACROSS THE AREA TONIGHT. BAND OF WAA SNOW MOVING ACROSS THE
AREA THIS MORNING IS TIED TO LIFT ON THE 290K ISENTROPIC SFC.
FOLLOWED SREF PROBS FAIRLY CLOSE FOR WORKING THIS BAND EAST ACROSS
MN THIS MORNING. LIGHT SNOW WILL LIKELY LINGER THROUGH MUCH OF
THE AFTERNOON ACROSS WI AS THEY WILL STAY TO THE NORTH OF THE
WARM/OCCLUDED FRONT. HOWEVER...QPF...EVEN IN WI LOOKS TO REMAIN
UNDER A 0.10"...WHICH STILL LEAVES US IN LINE FOR 0.5" TO 1.5" OF
SNOW. ALTHOUGH AMOUNTS WILL BE MINIMAL...SHOULD BE ENOUGH TO LEAD
TO A SLOWER COMMUTE THIS MORNING IN THE TWIN CITIES THANKS TO
TEMPERATURES STILL IN THE SINGLE DIGITS.
BY THE AFTERNOON THE SNOW WILL BE DONE FOR MOST OF MN...WITH SOME
FLURRIES LIKELY RETURNING IN THE WAKE OF THE COLD FRONT THIS
EVENING. CAA WILL RESULT IN STEEP LAPSE RATES...WHILE TEMPERATURES
WILL BE COLD ENOUGH THAT MUCH OF THE ATMO AND THEREFORE CLOUDS WILL
BE WITHIN THE DENDRITIC GROWTH ZONE...SO WILL NOT TAKE MUCH TO
GENERATE FLURRIES ACROSS THE AREA TONIGHT.
DID NOT CHANGE MUCH WITH THE GOING FORECAST IN TERMS OF HIGHS FOR
TODAY AS TEMPERATURES IN SW MN ARE ALREADY IN THE UPPER TEENS...SO
THERE THEY SHOULD HAVE NO PROBLEM WARMING THAT EXTRA 10-15 DEGREES
TO GET INTO THE 30S THIS AFTERNOON. THERE IS ALSO POTENTIAL THAT WE
MAY NOT BE WARM ENOUGH IN SW AND SC MN IF THEY MANAGE TO GET INTO
SOME SUNSHINE THIS AFTERNOON...WHICH IS PLAUSIBLE CONSIDERING SKIES
ARE MOSTLY CLEAR AT THE MOMENT WHEN YOU GET INTO NE NEB...SO WE
WILL HAVE TO SEE IF THAT CLEARING CAN FOLLOW THE WARM FRONT UP INTO
SRN MN.
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 423 AM CST FRI FEB 20 2015
THE TREND IS THE SAME IN THE LONG TERM WITH DRY AND COLD WEATHER
EXPECTED THROUGH THE FORECAST PERIOD AND BEYOND. THE LONG WAVE
RIDGE-TROUGH-RIDGE PATTERN STRETCHING FROM THE EASTERN PACIFIC TO
WESTERN ATLANTIC REMAINS IN PLACE THROUGH THE NEXT 7-10 DAYS OFF.
THERE IS GOOD CONSISTENCY AMONG THE OPERATIONAL AND ENSEMBLE
GFS/ECMWF WITH THE LONG WAVE EVOLUTION OVER THE PAST FEW RUNS.
THIS MEANS THE UPPER MISSISSIPPI VALLEY /AND MOST OF THE CONUS FOR
THAT MATTER/ WILL REMAIN FIRMLY UNDER THE UPPER TROUGH AND
CONTINUE TO SEE TEMPS 15 TO 30 BELOW NORMAL FOR THE SECOND HALF OF
FEBRUARY. WE`RE SLOWLY GAINING GROUND ON THE EXCEPTIONAL COLD
FEBRUARY WE HAD IN 2014...WHERE A LOT OF LOCATIONS IN MN/WI WERE
CLOSE TO -12 DEGREES FOR THE MONTHLY DEPARTURE. AS OF THIS
MORNING...MSP/STC/EAU WERE -6.9/-5.6/-8.4 RESPECTIVELY FOR THE
TEMPERATURE DEPARTURE SO FAR THIS MONTH. WE LOWERED OUR MONTHLY
DEPARTURE NEARLY A FULL DEGREE FROM YESTERDAY TO TODAY GIVEN THE
ROUGHLY 25 DEGREE BELOW NORMAL TEMP YESTERDAY. EVEN SMALL
VARIANCES TO FRONTAL TIMING OR THE SPECIFIC EVOLUTION OF
SHORTWAVE ENERGY EMBEDDED IN THE NORTHWEST FLOW WILL HAVE
RELATIVELY MINOR IMPACTS ON SENSIBLE WEATHER HIGHLIGHTS IN THE
LONG TERM. ANY APPRECIABLE SNOW/RAIN REMAINS WELL SOUTH/EAST OF
THE FORECAST AREA ON THE FRINGE OF THIS COLD CONTINENTAL AIR MASS.
WE EXPECT FLURRIES WITH THE CLOUD COVER ON SATURDAY MAINLY BECAUSE
WE`LL SIMPLY BE SATURATED IN THE DENDRITE GROWTH ZONE. THERE IS
VERY LITTLE LIFT. WE`LL BE QUITE BLUSTERY AT TIMES OVER THE NEXT
FEW DAYS...SO THAT COMBINED WITH CLOUD COVER BEHIND FRONTAL
PASSAGES, ETC. WILL HAVE AN IMPORTANT IMPACT ON JUST HOW COLD WE
GET - ESPECIALLY WITH OVERNIGHT LOWS.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SATURDAY MORNING)
ISSUED AT 554 AM CST FRI FEB 20 2015
BACK EDGE OF THE IFR BAND OF SNOW ALREADY WORKING INTO ERN MN THIS
MORNING. SREF PROBS FOR VIS LESS THAN 3SM HAS TRENDED WELL WITH
THE TIMING OF THE SNOW BAND ACROSS THE AREA OVERNIGHT...SO
FOLLOWED ITS TIMING FOR MOVING THE BACK EDGE ACROSS MN.
RAP/NAM/GFS ALSO SHOW ANOTHER QUICK BURST OF SNOW WORKING ACROSS
THE MN TERMINALS THIS EVENING WITH THE COLD FROPA...SO THAT IS WHY
A SECOND HINT OF SNOW SHOWS UP AT MOST MN TERMINALS THIS
AFTERNOON/EVENING. FOR WI...IT WILL LIKELY SNOW MUCH OF THE
DAY...THOUGH INTENSITY AND VSBY RESTRICTIONS WILL BE GREATEST THIS
MORNING. CIGS HAVE IMPROVED TO VFR LEVELS BEHIND THE SNOW...SO MAY
BE TO PESSIMISTIC ON MVFR CIGS REMAINING AT MSP. SREF MVFR CIG
PROBS SHOW THE MVFR CIGS WORKING EAST WITH THE SNOW...THOUGH
QUICKLY DROPPING BACK SE ACROSS THE AREA WITH THE FRONT. FOR
WINDS...STAYED CLOSE TO LAMP GUIDANCE...WHICH HAS A SIMILAR TIMING
TO THE HRRR AND NAM WITH THE FROPA.
KMSP...BEHIND THE SNOW THIS MORNING...AM CONCERNED WE WILL SEE
CIGS GO VFR FOR MUCH OF THE 15Z TO 22Z PERIOD BASED ON OBS
CURRENTLY TO THE SW. GFS/NAM/RAP/HRRR BUFR SOUNDINGS ALL SHOW
ANOTHER HIT OF -SN CENTERED AROUND 00Z AS THE FRONT COMES
THROUGH...SO JUST MOVED THE SECOND MENTION OF SNOW WE HAD BACK A
COUPLE OF HOURS. THROUGH THE NIGHT...WE SHOULD GRADUALLY SEE CIGS
WORK BACK ABOVE MVFR BY SAT MORNING. MAY ALSO SEE FLURRIES
THROUGH THE NIGHT...BUT NOT EXPECTING ANY VIS RESTRICTIONS IF WE
SEE ANY...SO LEFT ANY -SN OUT AFTER 2Z.
/OUTLOOK FOR KMSP/
SAT...VFR. WINDS NW AT 10-20KT.
SUN...VFR. WINDS NW 10-15KT.
MON...VFR. WINDS SW AT 10-15KT.
&&
.MPX WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...NONE.
&&
$$
SHORT TERM...MPG
LONG TERM...CLF
AVIATION...MPG
AREA FORECAST DISCUSSION
NWS JACKSON MS
1015 AM CST FRI FEB 20 2015
.UPDATE...THE LIGHT FREEZING PRECIPITATION CONTINUES THIS MORNING
OVER THE EAST AND NORTHEAST PORTIONS OF THE AREA AS TEMPERATURES
CONTINUE TO RISE. EXPECT ALL OF THE TEMPERATURES ACROSS THE AREA TO
RISE ABOVE FREEZING BY 11AM-NOON TODAY. FREEZING RAIN ADVISORIES ARE
IN EFFECT UNTIL 11 AM THIS MORNING FOR AREAS GENERALLY ALONG AND
NORTH OF THE I-20 CORRIDOR. OCCASIONAL LIGHT RAIN WILL CONTINUE TO
BE POSSIBLE THIS AFTERNOON...ESPECIALLY OVER THE NORTHERN PORTIONS
OF THE AREA. MADE SEVERAL ADJUSTMENTS TO THE FORECAST THIS MORNING
AND THE UPDATES AREA ALREADY OUT./15/
.DISCUSSION...
TODAY THROUGH SATURDAY NIGHT...
COLD AND DRY AIR REMAINS LOCKED IN OVER THE ARKLAMISS THIS
MORNING WITH DEWPOINT TEMPERATURES STILL IN THE SINGLE DIGITS FOR THE
MOST PART...BUT A DEVELOPING WARM FRONT WILL MOVE NORTHEAST AND
ACROSS THE ENTIRE AREA BY SATURDAY MORNING BRINGING MUCH WARMER
TEMPERATURES. FOR NOW...THERE CONTINUES TO BE SOME CONCERN FOR LIGHT
FREEZING RAIN AS THE STRENGTHENING WARM ADVECTION ABOVE THE SHALLOW
COLD AIR CREATES A SUBSTANTIAL MID LEVEL WARM LAYER IN THE THERMAL
PROFILES. ISENTROPIC LIFT IS CAUSING WIDESPREAD STRATUS TO FORM WITH
LIGHT WINTRY PRECIP JUST NOW DEVELOPING OVER PORTIONS OF CENTRAL AR.
AM MOST CONCERNED WITH PRECIPITATION MOVING INTO THE GREENWOOD TO
COLUMBUS CORRIDOR LATER THIS MORNING GIVEN THAT IS WHERE SUB-FREEZING
SURFACE AIR WILL BE TOUGHER TO WARM. RECENT HRRR GUIDANCE SHOWS THAT
VERY LIGHT PRECIP WILL CONTINUE TO SPREAD EASTWARD FROM AR INTO NORTH
CENTRAL MS...BUT GIVEN DRY AIR IN PLACE IT APPEARS MEASURABLE PCPN
WILL LIKELY HOLD OFF UNTIL THE AFTN/EVNG. HAVING SAID THAT...LATEST
GFS BUFR SOUNDINGS INDICATE THE COLD AIR MAY HANG ON A BIT MORE THAN
ANTICIPATED SO WILL NEED TO MONITOR CLOSELY THIS TREND. WITH THAT
SAID...LATEST WPC/SREF PTYPE PROBS INDICATE THAT THE RISK FOR
MEASURABLE FZRA SHOULD MOVE NORTH OF THE AREA BEFORE 00Z.
THE FORECAST IS MORE STRAIGHT-FORWARD FROM TONIGHT INTO SATURDAY WITH
TEMPERATURES HOLD STEADY OR RISING THROUGH THE PERIOD IN STRONG WARM
ADVECTION. INCREASING MOISTURE CONVERGENCE ALONG AN APPROACHING COLD
FRONT WILL GENERATE SHOWER ACTIVITY - AND LOCALLY HEAVY RAINFALL WILL
BECOME POSSIBLE AS A FAIRLY ROBUST MOISTURE PLUME IS DRAWN NORTHWARD
AND COMBINES WITH INCREASING INSTABILITY TO BRING TSTM POTENTIAL. IN
ADDITION...SIGNIFICANT PRESSURE FALLS WILL RESULT IN RATHER GUSTY
SOUTH WINDS AND A FEW GUSTS TO 30 MPH WILL BE LIKELY TONIGHT IN THE
DELTA REGION. GUIDANCE HAS SPED UP THE SOUTHEASTWARD-MOVING COLD
FRONT BY ROUGHLY 12 HOURS AND IT IS NOW EXPECTED TO PASS THROUGH THE
ENTIRE AREA BY EARLY SUNDAY MORNING...SO THIS WILL HELP TO LIMIT
RAINFALL TOTALS. /EC/
SUNDAY THROUGH NEXT FRIDAY...COLD AND WET CURRENTLY LOOK TO SUM UP
THE LONG TERM PORTION OF THE FORECAST...THIS GO AROUND. LIGHT RAIN
WILL LINGER BEHIND THE FRONT ON SUNDAY AS STRONG COLD ADVECTION SETS
UP ACROSS THE REGION. WITH MOISTURE ALOFT STILL RESIDING OVER THE
AREA LATE SUNDAY NIGHT INTO MONDAY MORNING AS A DISTURBANCE ALOFT
RACES EAST THROUGH THE REGION...AND VERY COLD DRY AIR UNDERCUTTING IT
AT THE SURFACE AND IN THE LOWER LEVELS OF THE ATMOSPHERE...SOME LIGHT
WINTRY PRECIPITATION COULD FALL OVER THE NORTHERN HALF OF THE CWA
EARLY MONDAY MORNING.
CLOUDS AND LIGHT RAIN AGAIN LINGER MONDAY AS ANOTHER MID/UPPER LEVEL
DISTURBANCE IS PROGGED TO RACE EAST THROUGH THE REGION.
AGAIN...WITH FREEZING TO SUB-FREEZING OVERNIGHT LOWS FORECAST OVER
MUCH OF THE REGION MONDAY NIGHT INTO TUESDAY MORNING...COUPLED WITH
MOISTURE ALOFT OVER THE REGION...SOME LIGHT WINTERY PRECIPITATION
CAN`T BE RULED OUT.
AFTER A BRIEF...BUT CONTINUED COLD...BREAK FROM PRECIPITATION ON
TUESDAY...CHANCES FOR PRECIPITATION AGAIN INCREASE WEDNESDAY.
THIS IS AS A RESULT OF AN MID/UPPER LEVEL TROUGH THAT`LL SWING EAST
ACROSS THE NATION`S MID-SECTION...CAUSING A SURFACE LOW TO DEVELOP
AND SHIFT EAST ALONG THE THE NORTHERN GULF COAST. SMALL PRECIP
CHANCES REMAIN IN THE FORECAST THURSDAY INTO FRIDAY AS ONCE AGAIN A
SERIES OF DISTURBANCES ALOFT RACE EAST THROUGH THE CWA. /19/
&&
.AVIATION...MVFR CIGS WERE BEING REPORTED AT 16Z ALONG THE HWY 82
CORRIDOR WHERE LIGHT FREEZING RAIN...LIGHT SLEET AND LIGHT SNOW WL
BE PSBL THROUGH 17Z. TEMPERATURES WILL RISE THROUGH THE AFTN AND
LIGHT RAIN WILL CONTINUE. CIGS WL RISE ABOVE 3KFT THIS AFTN AS WELL.
WIDESPREAD STRATUS WL CONTINUE TONIGHT AS A STRONG WARM FRONT MOVES
NORTH THE AREA. VFR CATEGORY CIGS THIS AFTN WILL REDUCE TO MVFR
CATEGORY CIGS BY LATE TONIGHT AT MOST SITES AND MODERATE RAIN
CHANCES WILL INCREASE AS WELL. /22/
&&
.PRELIMINARY POINT TEMPS/POPS...
JACKSON 53 51 67 48 / 21 56 66 84
MERIDIAN 48 45 65 51 / 13 47 49 82
VICKSBURG 58 55 70 44 / 25 73 74 85
HATTIESBURG 56 50 68 57 / 14 38 42 81
NATCHEZ 59 56 70 49 / 19 64 67 85
GREENVILLE 49 49 65 37 / 57 84 88 65
GREENWOOD 48 48 64 39 / 48 86 85 81
&&
.JAN WATCHES/WARNINGS/ADVISORIES...
MS...NONE.
LA...NONE.
AR...NONE.
&&
$$
/EC/19/
AREA FORECAST DISCUSSION
NWS JACKSON MS
518 AM CST FRI FEB 20 2015
.DISCUSSION...
TODAY THROUGH SATURDAY NIGHT...
COLD AND DRY AIR REMAINS LOCKED IN OVER THE ARKLAMISS THIS
MORNING WITH DEWPOINT TEMPERATURES STILL IN THE SINGLE DIGITS FOR THE
MOST PART...BUT A DEVELOPING WARM FRONT WILL MOVE NORTHEAST AND ACROSS
THE ENTIRE AREA BY SATURDAY MORNING BRINGING MUCH WARMER
TEMPERATURES. FOR NOW...THERE CONTINUES TO BE SOME CONCERN FOR LIGHT
FREEZING RAIN AS THE STRENGTHENING WARM ADVECTION ABOVE THE SHALLOW
COLD AIR CREATES A SUBSTANTIAL MID LEVEL WARM LAYER IN THE THERMAL
PROFILES. ISENTROPIC LIFT IS CAUSING WIDESPREAD STRATUS TO FORM WITH
LIGHT WINTRY PRECIP JUST NOW DEVELOPING OVER PORTIONS OF CENTRAL AR.
AM MOST CONCERNED WITH PRECIPITATION MOVING INTO THE GREENWOOD TO
COLUMBUS CORRIDOR LATER THIS MORNING GIVEN THAT IS WHERE SUB-FREEZING
SURFACE AIR WILL BE TOUGHER TO WARM. RECENT HRRR GUIDANCE SHOWS THAT
VERY LIGHT PRECIP WILL CONTINUE TO SPREAD EASTWARD FROM AR INTO NORTH
CENTRAL MS...BUT GIVEN DRY AIR IN PLACE IT APPEARS MEASURABLE PCPN
WILL LIKELY HOLD OFF UNTIL THE AFTN/EVNG. HAVING SAID THAT...LATEST
GFS BUFR SOUNDINGS INDICATE THE COLD AIR MAY HANG ON A BIT MORE THAN
ANTICIPATED SO WILL NEED TO MONITOR CLOSELY THIS TREND. WITH THAT
SAID...LATEST WPC/SREF PTYPE PROBS INDICATE THAT THE RISK FOR
MEASURABLE FZRA SHOULD MOVE NORTH OF THE AREA BEFORE 00Z.
THE FORECAST IS MORE STRAIGHT-FORWARD FROM TONIGHT INTO SATURDAY WITH
TEMPERATUERS HOLD STEADY OR RISING THROUGH THE PERIOD IN STRONG WARM
ADVECTION. INCREASING MOISTURE CONVERGENCE ALONG AN APPROACHING COLD
FRONT WILL GENERATE SHOWER ACTIVITY - AND LOCALLY HEAVY RAINFALL WILL
BECOME POSSIBLE AS A FAIRLY ROBUST MOISTURE PLUME IS DRAWN NORTHWARD
AND COMBINES WITH INCREASING INSTABILITY TO BRING TSTM POTENTIAL. IN
ADDITION...SIGNIFICANT PRESSURE FALLS WILL RESULT IN RATHER GUSTY
SOUTH WINDS AND A FEW GUSTS TO 30 MPH WILL BE LIKELY TONIGHT IN THE
DELTA REGION. GUIDANCE HAS SPED UP THE SOUTHEASTWARD-MOVING COLD
FRONT BY ROUGHLY 12 HOURS AND IT IS NOW EXPECTED TO PASS THROUGH THE
ENTIRE AREA BY EARLY SUNDAY MORNING...SO THIS WILL HELP TO LIMIT
RAINFALL TOTALS. /EC/
SUNDAY THROUGH NEXT FRIDAY...COLD AND WET CURRENTLY LOOK TO SUM UP
THE LONG TERM PORTION OF THE FORECAST...THIS GO AROUND. LIGHT RAIN
WILL LINGER BEHIND THE FRONT ON SUNDAY AS STRONG COLD ADVECTION SETS
UP ACROSS THE REGION. WITH MOISTURE ALOFT STILL RESIDING OVER THE
AREA LATE SUNDAY NIGHT INTO MONDAY MORNING AS A DISTURBANCE ALOFT
RACES EAST THROUGH THE REGION...AND VERY COLD DRY AIR UNDERCUTTING IT
AT THE SURFACE AND IN THE LOWER LEVELS OF THE ATMOSPHERE...SOME LIGHT
WINTRY PRECIPITATION COULD FALL OVER THE NORTHERN HALF OF THE CWA
EARLY MONDAY MORNING.
CLOUDS AND LIGHT RAIN AGAIN LINGER MONDAY AS ANOTHER MID/UPPER LEVEL
DISTURBANCE IS PROGGED TO RACE EAST THROUGH THE REGION.
AGAIN...WITH FREEZING TO SUB-FREEZING OVERNIGHT LOWS FORECAST OVER
MUCH OF THE REGION MONDAY NIGHT INTO TUESDAY MORNING...COUPLED WITH
MOISTURE ALOFT OVER THE REGION...SOME LIGHT WINTERY PRECIPITATION
CAN`T BE RULED OUT.
AFTER A BRIEF...BUT CONTINUED COLD...BREAK FROM PRECIPITATION ON
TUESDAY...CHANCES FOR PRECIPITATION AGAIN INCREASE WEDNESDAY.
THIS IS AS A RESULT OF AN MID/UPPER LEVEL TROUGH THAT`LL SWING EAST
ACROSS THE NATION`S MID-SECTION...CAUSING A SURFACE LOW TO DEVELOP
AND SHIFT EAST ALONG THE THE NORTHERN GULF COAST. SMALL PRECIP
CHANCES REMAIN IN THE FORECAST THURSDAY INTO FRIDAY AS ONCE AGAIN A
SERIES OF DISTURBANCES ALOFT RACE EAST THROUGH THE CWA. /19/
&&
.AVIATON...WIDESPREAD STRATUS WILL ENCOMPASS THE AREA TODAY AND
TONIGHT AS A STRONG WARM FRONT APPROACHES THE AREA. VFR CATEGORY CIGS
TODAY WILL REDUCE TO MVFR CATEGORY CIGS BY LATE TONIGHT AT MOST SITES
AS RAIN CHANCES INCREASE AS WELL. /EC/
&&
.PRELIMINARY POINT TEMPS/POPS...
JACKSON 53 51 67 48 / 21 56 66 84
MERIDIAN 48 45 65 51 / 13 47 49 82
VICKSBURG 58 55 70 44 / 25 73 74 85
HATTIESBURG 56 50 68 57 / 14 38 42 81
NATCHEZ 59 56 70 49 / 19 64 67 85
GREENVILLE 49 49 65 37 / 57 84 88 65
GREENWOOD 48 48 64 39 / 48 86 85 81
&&
.JAN WATCHES/WARNINGS/ADVISORIES...
MS...NONE.
LA...NONE.
AR...NONE.
&&
$$
/EC/19/
AREA FORECAST DISCUSSION
NWS OMAHA/VALLEY NE
1203 PM CST FRI FEB 20 2015
.SHORT TERM...(TODAY THROUGH SUNDAY)
ISSUED AT 330 AM CST FRI FEB 20 2015
PCPN CHANCES AND PCPN TYPE TONIGHT ACROSS OUR SOUTHERN COUNTIES
AND TEMPERATURES FOR ALL OF THE AREA THE NEXT FEW DAYS WILL
PROVIDE THE MAIN FORECAST CHALLENGES.
LARGE SCALE PATTERN AT 500 MB FEATURES A TROUGH FROM THE EASTERN
PACIFIC UP INTO ALASKA. TWO CLOSED LOWS WERE NOTED...ONE OVER NEW
YORK STATE AND THE OTHER OVER THE NORTHERN PART OF HUDSON BAY. OUR
AREA WAS IN NORTHWEST FLOW. 12 HOUR HEIGHT FALLS OF UP TO 60 METERS
WERE NOTED LAST EVENING FROM EASTERN WASHINGTON STATE INTO WESTERN
MONTANA. THROUGH SATURDAY THE RIDGE TO THE WEST WILL AMPLIFY A
BIT AND MOVE EAST...THEN A REX BLOCK FORMS BY SUNDAY.
TODAY WILL BE FAIRLY MILD AS THE ARCTIC AIRMASS WHICH HAS BEEN
OVER OUR AREA THE PAST COUPLE OF DAYS HAS LOOSENED ITS GRIP. WITH
WINDS GETTING MORE OF A WESTERLY COMPONENT TODAY...MOST LOCATIONS
SHOULD TOP OUT IN THE 30S AND 40S. NORTHEAST NEBRASKA APPEARS TO
HAVE THE BEST CHANCE OF SEEING MID 40S OR POSSIBLY EVEN WARMER.
EXPECT MOST OF THE AREA TO HAVE A GOOD AMOUNT OF MID AND/OR HIGH
LEVEL CLOUDS WHICH WILL DAMPEN WARMING A BIT. THERE IS SOME
QUESTION WHETHER LIGHT PCPN WILL DEVELOP OVER PARTS OF SOUTHEAST
NEBRASKA THIS AFTERNOON. LATEST HRRR AND 13 KM RAP MODELS KEEP
THINGS DRY...SO WILL TREND THAT WAY FOR NOW EVEN THOUGH SOME OTHER
MODELS DO SHOW SOME LIGHT AMOUNTS ARE POSSIBLE. THIS MAY NEED SOME
ADJUSTMENT LATER TODAY.
WINDS WILL TURN TO THE NORTH OR NORTHWEST TONIGHT AS YET ANOTHER
COLD FRONT SAGS SOUTHWARD ACROSS THE REGION. SOME FLURRIES WILL BE
POSSIBLE LATER TONIGHT AND INTO SATURDAY...ESPECIALLY NORTH. THE
MAIN PCPN WILL STAY ACROSS KANSAS AND MISSOURI...BUT HELD ONTO SOME
CHANCE POPS IN OUR SOUTHERN COUNTIES TO BLEND IN WITH NEIGHBORS TO
THE SOUTH. NAM/GFS AND ECMWF ALL HINT AT SOME MIXED PCPN. ADDED A
SLIGHT CHANCE THIS EVENING UP AS FAR NORTH AS OMAHA/COUNCIL
BLUFFS. THE PCPN TYPE COULD BE RAIN OR SNOW EARLY ON...THEN A MIX
OF RAIN/FREEZING RAIN/SNOW DEPENDING ON SURFACE TEMPERATURES. THE
00Z GFS AND 06Z NAM MODELS SEEMED JUST A BIT OVERDONE WITH QPF
ALONG THE KANSAS AND MISSOURI BORDERS TONIGHT.
TEMPERATURES SHOULD SLOWLY SLIDE DURING THE DAY SATURDAY AS COLD AIR
SETTLES SOUTH AHEAD OF A 1045 MB HIGH THAT WILL BUILD INTO SOUTHERN
SASKATCHEWAN BY SATURDAY EVENING...THEN TO THE EASTERN DAKOTAS BY
SUNDAY EVENING. EXPECT HIGHS SUNDAY TO ONLY BE IN THE TEENS. LOWS
SATURDAY NIGHT WILL BE SINGLE DIGITS...THEN MAINLY AROUND ZERO TO 5
ABOVE FOR SUNDAY NIGHT.
.LONG TERM...(SUNDAY NIGHT THROUGH THURSDAY)
ISSUED AT 330 AM CST FRI FEB 20 2015
TEMPERATURES WILL START TO MODERATE MONDAY...WITH HIGHS IN THE 20S.
THAT TREND SHOULD CONTINUE TUESDAY WITH HIGHS IN THE 30S...BUT A
COLD FRONT WILL PUSH THROUGH IN THE AFTERNOON. THEN BELOW NORMAL
TEMPERATURES SHOULD LAST INTO LATE WEEK.
BOTH THE 00Z GFS AND 00Z ECMWF AGREE THAT SOME LIGHT SNOW MAY
DEVELOP AS EARLY AS WEDNESDAY BUT CHANCES ARE A BIT HIGHER FOR
WEDNESDAY NIGHT...ESPECIALLY FOR OUR WESTERN COUNTIES. NOT OVERLY
CONFIDENT ON THIS AND TIMING WILL PROBABLY NEED SOME ADJUSTMENT
WITH FUTURE FORECASTS.
&&
.AVIATION...(18Z TAFS FOR KOFK...KLNK AND KOMA.)
ISSUED AT 1158 AM CST FRI FEB 20 2015
WE HAVE OPTED TO KEEP THE FORECAST DRY FOR THE TAF SITES IN
EASTERN NEBRASKA THROUGH 18Z SATURDAY. AN AREA OF LOW PRESSURE
WILL BRING PRECIPITATION TO AREAS SOUTH OF THE TAF SITES
TONIGHT...BUT DRY AIR OVER THE TAF SITES SHOULD PROHIBIT ANY RAIN
OR SNOW FROM REACHING THE GROUND. CIGS WILL LOWER TO AROUND FL
025-040 OVERNIGHT...THEN THE INCREASE AGAIN SATURDAY MORNING.
A COLD FRONT WILL MOVE THROUGH AND CAUSE NORTHWEST WINDS TO GUST
TO AROUND 20 KNOTS LATE MORNING SATURDAY.
&&
.OAX WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
IA...NONE.
&&
$$
SHORT TERM...MILLER
LONG TERM...MILLER
AVIATION...NIETFELD
AREA FORECAST DISCUSSION
NWS OMAHA/VALLEY NE
615 AM CST FRI FEB 20 2015
.SHORT TERM...(TODAY THROUGH SUNDAY)
ISSUED AT 330 AM CST FRI FEB 20 2015
PCPN CHANCES AND PCPN TYPE TONIGHT ACROSS OUR SOUTHERN COUNTIES
AND TEMPERATURES FOR ALL OF THE AREA THE NEXT FEW DAYS WILL
PROVIDE THE MAIN FORECAST CHALLENGES.
LARGE SCALE PATTERN AT 500 MB FEATURES A TROUGH FROM THE EASTERN
PACIFIC UP INTO ALASKA. TWO CLOSED LOWS WERE NOTED...ONE OVER NEW
YORK STATE AND THE OTHER OVER THE NORTHERN PART OF HUDSON BAY. OUR
AREA WAS IN NORTHWEST FLOW. 12 HOUR HEIGHT FALLS OF UP TO 60 METERS
WERE NOTED LAST EVENING FROM EASTERN WASHINGTON STATE INTO WESTERN
MONTANA. THROUGH SATURDAY THE RIDGE TO THE WEST WILL AMPLIFY A
BIT AND MOVE EAST...THEN A REX BLOCK FORMS BY SUNDAY.
TODAY WILL BE FAIRLY MILD AS THE ARCTIC AIRMASS WHICH HAS BEEN
OVER OUR AREA THE PAST COUPLE OF DAYS HAS LOOSENED ITS GRIP. WITH
WINDS GETTING MORE OF A WESTERLY COMPONENT TODAY...MOST LOCATIONS
SHOULD TOP OUT IN THE 30S AND 40S. NORTHEAST NEBRASKA APPEARS TO
HAVE THE BEST CHANCE OF SEEING MID 40S OR POSSIBLY EVEN WARMER.
EXPECT MOST OF THE AREA TO HAVE A GOOD AMOUNT OF MID AND/OR HIGH
LEVEL CLOUDS WHICH WILL DAMPEN WARMING A BIT. THERE IS SOME
QUESTION WHETHER LIGHT PCPN WILL DEVELOP OVER PARTS OF SOUTHEAST
NEBRASKA THIS AFTERNOON. LATEST HRRR AND 13 KM RAP MODELS KEEP
THINGS DRY...SO WILL TREND THAT WAY FOR NOW EVEN THOUGH SOME OTHER
MODELS DO SHOW SOME LIGHT AMOUNTS ARE POSSIBLE. THIS MAY NEED SOME
ADJUSTMENT LATER TODAY.
WINDS WILL TURN TO THE NORTH OR NORTHWEST TONIGHT AS YET ANOTHER
COLD FRONT SAGS SOUTHWARD ACROSS THE REGION. SOME FLURRIES WILL BE
POSSIBLE LATER TONIGHT AND INTO SATURDAY...ESPECIALLY NORTH. THE
MAIN PCPN WILL STAY ACROSS KANSAS AND MISSOURI...BUT HELD ONTO SOME
CHANCE POPS IN OUR SOUTHERN COUNTIES TO BLEND IN WITH NEIGHBORS TO
THE SOUTH. NAM/GFS AND ECMWF ALL HINT AT SOME MIXED PCPN. ADDED A
SLIGHT CHANCE THIS EVENING UP AS FAR NORTH AS OMAHA/COUNCIL
BLUFFS. THE PCPN TYPE COULD BE RAIN OR SNOW EARLY ON...THEN A MIX
OF RAIN/FREEZING RAIN/SNOW DEPENDING ON SURFACE TEMPERATURES. THE
00Z GFS AND 06Z NAM MODELS SEEMED JUST A BIT OVERDONE WITH QPF
ALONG THE KANSAS AND MISSOURI BORDERS TONIGHT.
TEMPERATURES SHOULD SLOWLY SLIDE DURING THE DAY SATURDAY AS COLD AIR
SETTLES SOUTH AHEAD OF A 1045 MB HIGH THAT WILL BUILD INTO SOUTHERN
SASKATCHEWAN BY SATURDAY EVENING...THEN TO THE EASTERN DAKOTAS BY
SUNDAY EVENING. EXPECT HIGHS SUNDAY TO ONLY BE IN THE TEENS. LOWS
SATURDAY NIGHT WILL BE SINGLE DIGITS...THEN MAINLY AROUND ZERO TO 5
ABOVE FOR SUNDAY NIGHT.
.LONG TERM...(SUNDAY NIGHT THROUGH THURSDAY)
ISSUED AT 330 AM CST FRI FEB 20 2015
TEMPERATURES WILL START TO MODERATE MONDAY...WITH HIGHS IN THE 20S.
THAT TREND SHOULD CONTINUE TUESDAY WITH HIGHS IN THE 30S...BUT A
COLD FRONT WILL PUSH THROUGH IN THE AFTERNOON. THEN BELOW NORMAL
TEMPERATURES SHOULD LAST INTO LATE WEEK.
BOTH THE 00Z GFS AND 00Z ECMWF AGREE THAT SOME LIGHT SNOW MAY
DEVELOP AS EARLY AS WEDNESDAY BUT CHANCES ARE A BIT HIGHER FOR
WEDNESDAY NIGHT...ESPECIALLY FOR OUR WESTERN COUNTIES. NOT OVERLY
CONFIDENT ON THIS AND TIMING WILL PROBABLY NEED SOME ADJUSTMENT
WITH FUTURE FORECASTS.
&&
.AVIATION...(12Z TAFS FOR KOFK...KLNK AND KOMA.)
ISSUED AT 615 AM CST FRI FEB 20 2015
VFR CONDITIONS ARE EXPECTED TO PREVAIL FOR MOST OF THE PERIOD
WITH INCREASING MID LEVEL CIGS. POTENTIAL FOR MVFR CIGS AFTER 06Z
AS MOISTURE SPREADS NORTH IN ADVANCE OF SOUTHERN PLAINS LOW AND
COLDER AIR WORKS IN FROM THE NORTH.
&&
.OAX WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
IA...NONE.
&&
$$
SHORT TERM...MILLER
LONG TERM...MILLER
AVIATION...FOBERT
AREA FORECAST DISCUSSION
NWS OMAHA/VALLEY NE
330 AM CST FRI FEB 20 2015
.SHORT TERM...(TODAY THROUGH SUNDAY)
ISSUED AT 330 AM CST FRI FEB 20 2015
PCPN CHANCES AND PCPN TYPE TONIGHT ACROSS OUR SOUTHERN COUNTIES
AND TEMPERATURES FOR ALL OF THE AREA THE NEXT FEW DAYS WILL
PROVIDE THE MAIN FORECAST CHALLENGES.
LARGE SCALE PATTERN AT 500 MB FEATURES A TROUGH FROM THE EASTERN
PACIFIC UP INTO ALASKA. TWO CLOSED LOWS WERE NOTED...ONE OVER NEW
YORK STATE AND THE OTHER OVER THE NORTHERN PART OF HUDSON BAY. OUR
AREA WAS IN NORTHWEST FLOW. 12 HOUR HEIGHT FALLS OF UP TO 60 METERS
WERE NOTED LAST EVENING FROM EASTERN WASHINGTON STATE INTO WESTERN
MONTANA. THROUGH SATURDAY THE RIDGE TO THE WEST WILL AMPLIFY A
BIT AND MOVE EAST...THEN A REX BLOCK FORMS BY SUNDAY.
TODAY WILL BE FAIRLY MILD AS THE ARCTIC AIRMASS WHICH HAS BEEN
OVER OUR AREA THE PAST COUPLE OF DAYS HAS LOOSENED ITS GRIP. WITH
WINDS GETTING MORE OF A WESTERLY COMPONENT TODAY...MOST LOCATIONS
SHOULD TOP OUT IN THE 30S AND 40S. NORTHEAST NEBRASKA APPEARS TO
HAVE THE BEST CHANCE OF SEEING MID 40S OR POSSIBLY EVEN WARMER.
EXPECT MOST OF THE AREA TO HAVE A GOOD AMOUNT OF MID AND/OR HIGH
LEVEL CLOUDS WHICH WILL DAMPEN WARMING A BIT. THERE IS SOME
QUESTION WHETHER LIGHT PCPN WILL DEVELOP OVER PARTS OF SOUTHEAST
NEBRASKA THIS AFTERNOON. LATEST HRRR AND 13 KM RAP MODELS KEEP
THINGS DRY...SO WILL TREND THAT WAY FOR NOW EVEN THOUGH SOME OTHER
MODELS DO SHOW SOME LIGHT AMOUNTS ARE POSSIBLE. THIS MAY NEED SOME
ADJUSTMENT LATER TODAY.
WINDS WILL TURN TO THE NORTH OR NORTHWEST TONIGHT AS YET ANOTHER
COLD FRONT SAGS SOUTHWARD ACROSS THE REGION. SOME FLURRIES WILL BE
POSSIBLE LATER TONIGHT AND INTO SATURDAY...ESPECIALLY NORTH. THE
MAIN PCPN WILL STAY ACROSS KANSAS AND MISSOURI...BUT HELD ONTO SOME
CHANCE POPS IN OUR SOUTHERN COUNTIES TO BLEND IN WITH NEIGHBORS TO
THE SOUTH. NAM/GFS AND ECMWF ALL HINT AT SOME MIXED PCPN. ADDED A
SLIGHT CHANCE THIS EVENING UP AS FAR NORTH AS OMAHA/COUNCIL
BLUFFS. THE PCPN TYPE COULD BE RAIN OR SNOW EARLY ON...THEN A MIX
OF RAIN/FREEZING RAIN/SNOW DEPENDING ON SURFACE TEMPERATURES. THE
00Z GFS AND 06Z NAM MODELS SEEMED JUST A BIT OVERDONE WITH QPF
ALONG THE KANSAS AND MISSOURI BORDERS TONIGHT.
TEMPERATURES SHOULD SLOWLY SLIDE DURING THE DAY SATURDAY AS COLD AIR
SETTLES SOUTH AHEAD OF A 1045 MB HIGH THAT WILL BUILD INTO SOUTHERN
SASKATCHEWAN BY SATURDAY EVENING...THEN TO THE EASTERN DAKOTAS BY
SUNDAY EVENING. EXPECT HIGHS SUNDAY TO ONLY BE IN THE TEENS. LOWS
SATURDAY NIGHT WILL BE SINGLE DIGITS...THEN MAINLY AROUND ZERO TO 5
ABOVE FOR SUNDAY NIGHT.
.LONG TERM...(SUNDAY NIGHT THROUGH THURSDAY)
ISSUED AT 330 AM CST FRI FEB 20 2015
TEMPERATURES WILL START TO MODERATE MONDAY...WITH HIGHS IN THE 20S.
THAT TREND SHOULD CONTINUE TUESDAY WITH HIGHS IN THE 30S...BUT A
COLD FRONT WILL PUSH THROUGH IN THE AFTERNOON. THEN BELOW NORMAL
TEMPERATURES SHOULD LAST INTO LATE WEEK.
BOTH THE 00Z GFS AND 00Z ECMWF AGREE THAT SOME LIGHT SNOW MAY
DEVELOP AS EARLY AS WEDNESDAY BUT CHANCES ARE A BIT HIGHER FOR
WEDNESDAY NIGHT...ESPECIALLY FOR OUR WESTERN COUNTIES. NOT OVERLY
CONFIDENT ON THIS AND TIMING WILL PROBABLY NEED SOME ADJUSTMENT
WITH FUTURE FORECASTS.
&&
.AVIATION...(06Z TAFS FOR KOFK...KLNK AND KOMA.)
ISSUED AT 1114 PM CST THU FEB 19 2015
LOW LEVEL WIND SHEAR WILL BE THE INITIAL CONCERN WITH WINDS AT
2000 FEET AROUND 40 KNOTS. THAT EASES BY 13Z AS LOW LEVEL JET
WEAKENS. OTHERWISE...VFR CONDITIONS THROUGH THE PERIOD.
&&
.OAX WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
IA...NONE.
&&
$$
SHORT TERM...MILLER
LONG TERM...MILLER
AVIATION...DEWALD
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
958 PM EST SAT FEB 21 2015
.SYNOPSIS...
HIGH PRESSURE OFFSHORE WILL CIRCULATE MILD AIR INTO THE REGION
WITH TEMPERATURES IN THE 60S SUNDAY. A GOOD CHANCE OF SIGNIFICANT
RAIN IS EXPECTED SUNDAY NIGHT AND MONDAY...AS GULF MOISTURE IS LIFTED
AHEAD OF AN UPPER TROUGH MOVING ACROSS THE EAST COAST. COLD AIR WILL
RETURN LATE MONDAY AS ARCTIC HIGH PRESSURE BUILDS IN. COLD AND
UNSETTLED WEATHER IS EXPECTED MUCH OF THE UPCOMING WEEK AS CHILLY
HIGH PRESSURE AND GULF MOISTURE INTERACT.
&&
.NEAR TERM /UNTIL 6 AM SUNDAY MORNING/...
AS OF 955 PM SATURDAY...THE LINE OF SHOWERS HAS DEVELOPED FROM
BRUNSWICK INTO WESTERN PENDER COUNTIES. THE HRRR 23 AND 00 UTC RUN
BOTH ARE SHOWING THE PRECIPITATION MOVING OFF THE COAST AFTER 05
UTC. AS THIS MOVES OUT THE THE NEXT AREA OF RAIN AHEAD OF THE COLD
FRONT THAT WILL BE ENTERING WESTERN NORTH CAROLINA WILL MOVE INTO
THE WESTERN PORTIONS OF THE FORECAST AREA JUST BEFORE SUNRISE.
TEMPS OVERNIGHT WILL REMAIN WARM WITH MID 40S INLAND AND NEAR 50
CLOSER TO THE COAST.
&&
.SHORT TERM /6 AM SUNDAY MORNING THROUGH MONDAY NIGHT/...
AS OF 3 PM SATURDAY...PRIMARY WEATHER HEADLINES SUNDAY AND MONDAY
ARE PROSPECTS OF A DECENT SOAKER OF A RAIN EVENT SUNDAY NIGHT TO
MONDAY MORNING...FOLLOWED BY A VERY SLIGHT CHANCE OF A FEW SNOW
FLURRIES LATE ON MONDAY.
GULF OF MEXICO TAP TO PLAY A NOTABLE ROLE IN ELEVATING DEEP COLUMN
MOISTURE 18Z SUN-00Z TUE...WITH STORM TOTAL CALCULATIONS PROGGING
ABOUT AN INCH OF RAINFALL ACROSS NE SC AND SE NC. THE BULK OF THIS
APT TO FALL AS 6Z-18Z MONDAY AS ISENTROPIC OMEGA INCREASES.
STRONG COLD AIR ADVECTION MONDAY AS HIGH PRESSURE OF ARCTIC BIRTH
BARGES IN...WITH DIURNAL TEMPERATURE RANGES NARROW IN THE BATTLE
WITH DAYTIME WARMING. VERY COLD AIR LATER IN THE DAY MONDAY AND
NIGHT ON THE HEELS OF EGRESSING MOISTURE...COULD OPEN A WINDOW
OF BRIEF SNOW FLURRIES. DEEP COLD CONVECTION UNLIKELY SINCE DRY
AIR ENCROACHMENT ABOVE 850 MB WILL ALREADY BE UNDERWAY.
MILDEST PERIOD SUNDAY AFTERNOON WITH 60S WIDESPREAD AWAY FROM THE
IMMEDIATE BEACHES. COLDEST PERIOD EARLY TUES AS ARCTIC AIR SPILLS
INTO THE CAROLINAS...MINIMUMS DAYBREAK TUESDAY 24-31 DEGREES.
&&
.LONG TERM /TUESDAY THROUGH SATURDAY/...
AS OF 345 PM SATURDAY...SUBTLE PATTERN SHIFT THROUGH THE EXTENDED
WILL LEAD TO CONTINUED COLD AIR ENTRENCHED ACROSS THE EAST...WITH
THE SOUTHERN STREAM BECOMING THE DOMINANT WEATHER MAKER THROUGH THE
WEEK.
LONG-WAVE TROUGH WHICH HAS PLAGUED THE EASTERN CONUS FOR THE PAST
MONTH WILL REMAIN...BUT IN A LESS AMPLIFIED SETUP. THE TROUGH WILL
BROADEN SUCH THAT IT EXTENDS WELL INTO THE ATLANTIC...AND WHILE THIS
WILL DO LITTLE TO REMEDY THE COLD...IT WILL KEEP MOST OF THE
PRECIPITATION SUPPRESSED TO THE SOUTH. COLD FRONT WILL BE STALLED
WELL SOUTH OF THE AREA TUESDAY MORNING...AND ALONG THIS BAROCLINIC
GRADIENT IS WHERE A SERIES OF SHORTWAVES AND WEAK LOW PRESSURES WILL
ROTATE THROUGH THE WEEK. THIS KEEPS AT LEAST A SCHC OF
PRECIP...ESPECIALLY SE ZONES...THROUGH THE WEEK. TIMING OF THESE
INDIVIDUAL SHORTWAVES AND SURFACE REFLECTIONS IS DIFFICULT...SO WILL
MAKE LITTLE CHANGE TO INHERITED POP...AND KEEP A SCHC OF PRECIP
ALONG THE COAST/SOUTH THROUGH THE WEEK. LOCAL TOP-DOWN METHODOLOGY
DOES PRODUCE PERIODS OF R/S OR R/IP/ZR...PRETTY MUCH EACH DAY.
CONFIDENCE IS LOW IN TIMING...AND TEMPS WILL WARM ABOVE FREEZING
EACH AFTN SO HAVE OPTED TO KEEP ONLY LIQUID PRECIP FOR NOW THROUGH
THURSDAY. HOWEVER...NEED TO MENTION THAT THERE VERY WELL COULD BE
PERIODS OF WINTRY MIXED PRECIP...ALMOST ANY DAY THROUGH THE WEEK.
TEMPS TUE-FRI WILL REMAIN WELL BELOW NORMAL FOR THE
PERIOD...AVERAGING ABOUT 10 DEGREES BELOW CLIMO.
LATE IN THE PERIOD THINGS GET A LITTLE MORE INTERESTING AS A STRONG
SURFACE WEDGE RE-BUILDS DOWN THE COAST AHEAD OF A MORE SIGNIFICANT
LOW PRESSURE SYSTEM. GUIDANCE AGREES THAT A COASTAL TROUGH WILL
SHARPEN AND CLOSE OFF ON SATURDAY...BUT THE INTENSITY AND TRACK OF
THE LOW IS STILL VERY MUCH IN QUESTION. WITH THE STRONG COLD WEDGE
IN PLACE...WE COULD BE LOOKING AT A MIXED P-TYPE EVENT FRIDAY NIGHT
INTO SATURDAY...BUT GUIDANCE DOES SHOW A QUICK WARMUP SATURDAY WHICH
WOULD TRANSITION TO ALL RAIN. LOTS OF UNCERTAINTY AT THIS TIME
RANGE...BUT THIS CONTINUES TO BE SUPPORTED BY GUIDANCE REGARDLESS OF
THE STRICT PATTERN EVOLUTION. WITH TEMPS BELOW FREEZING AND CHC POP
WARRANTED...AFTER COLLABORATION WITH NEIGHBORS HAVE OPTED TO INCLUDE
THE ZR CREATED FROM TOP-DOWN FOR FRIDAY NIGHT INTO SATURDAY. STILL A
LOT CAN CHANGE...BUT FRIDAY NIGHT INTO SATURDAY COULD GET MESSY
ACROSS THE AREA.
&&
.AVIATION /03Z SUNDAY THROUGH THURSDAY/...
AS OF 00Z...SOME SEA FOG MOVING ALONG THE SC COAST HAS IMPACTED MYR
AT THIS TIME AND IS TRYING TO PUSH INTO CRE. WILL ADD LOW CEILINGS
AND VSBY TO REFLECT THE CHANCE OF THIS OVER THE NEXT FEW HOURS AND
DURING THE OVERNIGHT TIME FRAME. MEDIUM CONFIDENCE IN THE SEA FOG
ALONG THE SC COAST AND LOWE CONFIDENCE OF IT ACROSS THE ILM
TERMINAL. MODELS KEEP A SLUG OF MOISTURE RIDING UP THE SC/NC COAST
DURING THE NEXT SEVERAL HOURS ALBEIT LIGHT AND KEEP THE INLAND
TERMINALS DRY. THIS REVERSES ON SUNDAY AHEAD OF THE NEXT SYSTEM
WITH THE INLAND TERMINALS SEEING PCPN DURING THE AFTERNOON AND THE
COASTAL TERMINALS STAYING DRY FOR THE MOST PART. BIGGEST CONCERNS
DURING THE NEXT SEVERAL HOURS WILL BE HOW LONG THE SEA FOG WILL
LAST AND IF IT WILL MAKE IT TO THE ILM TERMINAL. WILL MONITOR FOR
UPDATES
EXTENDED OUTLOOK...A SERIES OF WEAK SYSTEMS WILL MOVE THROUGH THE
REGION THROUGH THE FORECAST PERIOD...WITH PERIODS OF LIGHT PRECIP
POSSIBLE EACH DAY.
&&
.MARINE...
NEAR TERM /THROUGH TONIGHT/...
AS OF 955 PM SATURDAY...SOUTH TO SOUTHEAST WIND FLOW CONTINUES AND
BUOYS ARE SHOWING WINDS 10 TO 15 KNOTS NEAR SHORE AND AROUND 25
KNOTS AT FRYING PAN. SEAS AT FRYING PAN ARE SHOWING 8 FEET WITH
THE HARBOR BUOY AT THE MOUTH OF THE CAPE FEAR RIVER NOW AT 5.5
FEET. WILL CONTINUE SMALL CRAFT THROUGH 7 AM FOR ENTIRE WATERS AND
ONLY FOR WATERS NORTH OF LITTLE RIVER INLET BY 10 AM. ALSO WITH
THE WARMER AIR MOIST AIR WE CAN EXPECT SOME PATCHY SEA FOG
OVERNIGHT.
SHORT TERM /SUNDAY THROUGH MONDAY NIGHT/...
AS OF 3 PM SATURDAY...ADVISORIES MAY BE NEEDED EARLY SUNDAY AS
SEA HEIGHTS RECOVER FROM THE PRESENT SE WAVE-BUILDING FETCH. AN
ADVISORY WILL AGAIN BE NEEDED MOST IF NOT ALL OF MONDAY AS NORTH
WINDS RIP ACROSS THE WATERS...DUE TO AN ARCTIC HIGH TAKEOVER.
A WAVE DIRECTION TRANSITION TO BISECT THIS TIME PERIOD AS S WAVE
ENERGY TURNS TO N AND NE MONDAY AND BUILDS WAVE-HEIGHTS AT TO
ABOVE ADVISORY RANGE IN TANDEM WITH ADVISORY WINDS TO BOOT. NO
TSTMS EXPECTED BUT PATCHY FOG WILL PLAGUE THE WATERS EARLY SUNDAY.
LONG TERM /TUESDAY THROUGH THURSDAY/...
AS OF 345 PM SATURDAY...COLD FRONT WILL REMAIN STALLED JUST SOUTH OF
THE WATERS THROUGH THE EXTENDED...WHILE WAVES OF LOW PRESSURE MOVE
ALONG THIS BOUNDARY. THE PERIOD WILL BE BOOK-ENDED BY GUSTY N/NE
WINDS BOTH EARLY TUESDAY AND AGAIN LATE THURSDAY...AS THE GRADIENT
TIGHTENS NEAR LOW PRESSURE SYSTEMS MOVING WELL OFF THE COAST. SPEEDS
DURING THESE NE SURGES WILL BE AROUND 15-20 KT. WINDS EASE AND
BACK TO THE NW TUESDAY NIGHT AND THROUGH WEDNESDAY AS HIGH
PRESSURE RIDGES TOWARDS THE WATERS FROM THE NW...BEFORE AGAIN
INCREASING LATE THURSDAY AS MENTIONED ABOVE. SEAS WILL BE 3-5 FT
EARLY TUESDAY ON THE GUSTY NE WINDS...BEFORE EASING LATE TO 2-3 FT
AND REMAINING AT THESE AMPLITUDES THROUGH WEDNESDAY NIGHT. AS THE
WINDS RISE ON THURSDAY...SEAS BUILD AGAIN QUICKLY...AND AN
EXTENDED PERIOD OF SCA CONDITIONS MAY DEVELOP BEGINNING THURSDAY.
&&
.ILM WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
NC...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 6 AM EST SUNDAY FOR AMZ254-256.
SMALL CRAFT ADVISORY UNTIL 10 AM EST SUNDAY FOR AMZ250-252.
&&
$$
NEAR TERM...HAWKINS
SHORT TERM...MJC
LONG TERM...JDW
AVIATION...CAROPOLO
AREA FORECAST DISCUSSION
NWS GRAND FORKS ND
1215 PM CST FRI FEB 20 2015
.UPDATE...
ISSUED AT 1215 PM CST FRI FEB 20 2015
NO CHANGES NEEDED FOR THIS UPDATE.
&&
.SHORT TERM...(TODAY THROUGH SATURDAY)
ISSUED AT 300 AM CST FRI FEB 20 2015
SNOW CHANCES TODAY AND TONIGHT WILL BE THE MAIN FORECAST
CHALLENGE...THEN WINDS TOMORROW.
NORTHWESTERLY FLOW ALOFT CONTINUES OVER THE NORTHERN PLAINS AND WV
LOOP SHOWS SEVERAL WEAK SHORTWAVES UPSTREAM. THE FIRST SHORTWAVE
CURRENTLY IS DIGGING INTO NORTHEASTERN SOUTH DAKOTA...AND THERE
HAS BEEN SOME LIGHT SNOW IN THE WARM AIR ADVECTION AHEAD OF THE
SFC LOW CURRENTLY ENTERING THE NORTHEASTERN CWA. THE LIGHT SNOW
HAS STARTED TO COME TO AN END ACROSS THE NORTHWESTERN
COUNTIES...SO THE TREND IN POPS TO PUSH HIGHEST PROBABILITIES OFF
TO THE EAST THIS MORNING SEEMS GOOD. THE RAP HAS THE NEXT WEAK
SHORTWAVES COMING THROUGH MAINLY ACROSS CENTRAL AND WESTERN
ND...WHICH FITS WITH CURRENT CANADIAN RADAR. MUCH OF THE SNOW FROM
THESE SHORTWAVES WILL REMAIN TO OUR WEST BUT CONTINUED TO KEEP
SOME LOW POPS IN OUR WESTERN COUNTIES IN CASE SOME LIGHT SNOW
CLIPS THAT AREA. WITH THE FIRST MORNING SHORTWAVE MOVING EAST AND
THE NEXT SHORTWAVES MAINLY FOCUSED ON THE FAR WESTERN TIER...THINK
THAT THERE WILL BE A PERIOD FOR THE CENTRAL CWA TODAY WHERE ONLY
LINGERING FLURRIES REMAINS. EVEN THOSE AREAS THAT GET ACCUMULATION
WILL SEE A HALF AN INCH AT MOST. THERE SHOULD BE ANOTHER LOW
CHANCE FOR ACCUMULATING SNOW AREA WIDE AS THE ARCTIC FRONT COMES
DOWN TONIGHT...BUT AGAIN IT WILL BE A DUSTING AT MOST.
TEMPS SHOULD BE FAIRLY MILD TODAY WITH GWINNER ALREADY AT 21
DEGREES AT 08Z. CONTINUED TO KEEP HIGHS IN THE TEENS IN THE NORTH
TO LOW 30S IN THE SOUTH. THE MILD TEMPS WILL END TONIGHT AS ARCTIC
AIR PLUNGES BACK SOUTH INTO THE CWA. WITH THE UPPER TROUGH DIGGING
DOWN OUT OF CANADA...ALL MODELS HAVE 850MB TEMPS BACK BELOW -20 C
FOR SATURDAY. CONTINUED TO KEEP HIGHS EITHER SIDE OF ZERO. WITH
COLD AIR ADVECTION AND A DECENT GRADIENT AHEAD OF THE ARCTIC
HIGH...NORTH WINDS COULD BECOME RATHER BREEZY SATURDAY. THE
BLOWING SNOW MODEL DOES NOT GIVE MUCH PROBABILITY DUE TO NO
FALLING SNOW AT THE TIME...BUT WILL HAVE TO WATCH WINDS ON
SATURDAY AS 925MB SPEEDS GET UP TO 25 KTS. THE WINDS WILL ALSO
KNOCK APPARENT TEMPS DOWN BELOW ADVISORY CRITERIA AT TIMES
ALTHOUGH TIMING IS STILL UNCERTAIN AT THIS POINT.
.LONG TERM...(SATURDAY NIGHT THROUGH THURSDAY)
ISSUED AT 300 AM CST FRI FEB 20 2015
SATURDAY NIGHT THROUGH SUNDAY NIGHT...CONDITIONS WILL REMAIN DRY
BUT COLD AS ARCTIC HIGH PRESSURE CONTINUES TO BUILD INTO THE AREA.
DEPENDING ON HOW MUCH WE CLEAR OUT...TEMPS SATURDAY NIGHT COULD
FALL BELOW 20 BELOW AND WITH SOME GRADIENT REMAINING...WIND CHILLS
MAY BE LOWER THEN 40 BELOW BY SUNDAY MORNING. THE SFC HIGH CENTER
BUILDING IN ON SUNDAY WILL CONTINUE WITH FRIGID TEMPS NOT RISING
INTO THE POSITIVE DIGITS. THE SFC HIGH WILL BEGIN TO SINK
SOUTHEASTWARD SUNDAY NIGHT AND WINDS WILL START PICKING UP WITH
SOME WARM AIR ADVECTION LATE IN THE NIGHT. TEMPS MAY START RISING
IN THE WEST...BUT NOT BEFORE BOTTOMING OUT IN THE TEENS BELOW
ZERO.
MONDAY THROUGH THURSDAY...THE EXTENDED BEGINS WITH A PAIR OF UPPER LEVEL
DISTURBANCES UPSTREAM IN CENTRAL CANADA. THE FIRST/WEAKER WAVE MAY
BRING A FEW FLURRIES TO THE AREA MONDAY AFTERNOON/EVENING...BUT A
BETTER CHANCE LOOKS TO COME LATER IN THE NIGHT WITH THE SECOND
WAVE. STILL...MOISTURE LOOKS LIMITED. SURFACE WINDS WILL BE
SOUTHWESTERLY ON MONDAY AHEAD OF A COLD FRONT ASSOCIATED WITH THE
SURFACE LOW PRESSURE SYSTEM. TEMPS AT 850 MB WARM CONSIDERABLY
FROM SUNDAY MORNING TO MONDAY MORNING... NEARLY 20C IN 30 HRS. THE
RESULT WILL BE HIGHS ABOUT 30 DEGREES WARMER ON MONDAY THAN ON
SUNDAY. THE COLD FRONT WILL THEN BARREL THROUGH THE AREA ON
TUESDAY MORNING. THE GOOD NEWS IS THAT IT IS EXPECTED TO BE A
GLANCING BLOW...WITH THE COLDEST AIR OFF TO THE EAST OVER FAR NE
MN AND LAKE SUPERIOR. THE BAD NEWS IS THAT STAGNANT COLD HIGH
PRESSURE WILL SET UP OVER THE NORTHERN PLANS TO END THE WEEK.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON)
ISSUED AT 1215 PM CST FRI FEB 20 2015
MVFR CONDITIONS CONTINUING WITH WINDS BECOMING NORTHERLY BEHIND A
LOW PRESSURE SYSTEM. SOME SCT -SN WILL OCCUR OVER THE AREA BUT WILL
DIMINISH BY LATE AFTERNOON. CONDITIONS EXPECTED TO BECOME VFR LATE
IN THE PERIOD AS HIGH PRESSURE AND SUBSIDENCE SHIFTS OVER THE AREA.
&&
.FGF WATCHES/WARNINGS/ADVISORIES...
ND...NONE.
MN...NONE.
&&
$$
UPDATE...DK
SHORT TERM...JR
LONG TERM...JR/KNUTSVIG
AVIATION...HOPKINS
AREA FORECAST DISCUSSION
NWS GRAND FORKS ND
939 AM CST FRI FEB 20 2015
.UPDATE...
ISSUED AT 940 AM CST FRI FEB 20 2015
WE HAVE ADDED SOME FREEZING DRIZZLE TO NW MN FROM BDE-BJI...SINCE
WE HAVE GOTTEN SOME REPORTS HERE. THIS THREAT SHOULD PERSIST
THROUGH EARLY AFTERNOON UNTIL THE COLUMN COOLS SUFFICIENTLY FOR
SOME FLURRIES/LIGHT SNOW. OTHERWISE...NO OTHER CHANGES NEEDED THIS
MORNING.
&&
.SHORT TERM...(TODAY THROUGH SATURDAY)
ISSUED AT 300 AM CST FRI FEB 20 2015
SNOW CHANCES TODAY AND TONIGHT WILL BE THE MAIN FORECAST
CHALLENGE...THEN WINDS TOMORROW.
NORTHWESTERLY FLOW ALOFT CONTINUES OVER THE NORTHERN PLAINS AND WV
LOOP SHOWS SEVERAL WEAK SHORTWAVES UPSTREAM. THE FIRST SHORTWAVE
CURRENTLY IS DIGGING INTO NORTHEASTERN SOUTH DAKOTA...AND THERE
HAS BEEN SOME LIGHT SNOW IN THE WARM AIR ADVECTION AHEAD OF THE
SFC LOW CURRENTLY ENTERING THE NORTHEASTERN CWA. THE LIGHT SNOW
HAS STARTED TO COME TO AN END ACROSS THE NORTHWESTERN
COUNTIES...SO THE TREND IN POPS TO PUSH HIGHEST PROBABILITIES OFF
TO THE EAST THIS MORNING SEEMS GOOD. THE RAP HAS THE NEXT WEAK
SHORTWAVES COMING THROUGH MAINLY ACROSS CENTRAL AND WESTERN
ND...WHICH FITS WITH CURRENT CANADIAN RADAR. MUCH OF THE SNOW FROM
THESE SHORTWAVES WILL REMAIN TO OUR WEST BUT CONTINUED TO KEEP
SOME LOW POPS IN OUR WESTERN COUNTIES IN CASE SOME LIGHT SNOW
CLIPS THAT AREA. WITH THE FIRST MORNING SHORTWAVE MOVING EAST AND
THE NEXT SHORTWAVES MAINLY FOCUSED ON THE FAR WESTERN TIER...THINK
THAT THERE WILL BE A PERIOD FOR THE CENTRAL CWA TODAY WHERE ONLY
LINGERING FLURRIES REMAINS. EVEN THOSE AREAS THAT GET ACCUMULATION
WILL SEE A HALF AN INCH AT MOST. THERE SHOULD BE ANOTHER LOW
CHANCE FOR ACCUMULATING SNOW AREA WIDE AS THE ARCTIC FRONT COMES
DOWN TONIGHT...BUT AGAIN IT WILL BE A DUSTING AT MOST.
TEMPS SHOULD BE FAIRLY MILD TODAY WITH GWINNER ALREADY AT 21
DEGREES AT 08Z. CONTINUED TO KEEP HIGHS IN THE TEENS IN THE NORTH
TO LOW 30S IN THE SOUTH. THE MILD TEMPS WILL END TONIGHT AS ARCTIC
AIR PLUNGES BACK SOUTH INTO THE CWA. WITH THE UPPER TROUGH DIGGING
DOWN OUT OF CANADA...ALL MODELS HAVE 850MB TEMPS BACK BELOW -20 C
FOR SATURDAY. CONTINUED TO KEEP HIGHS EITHER SIDE OF ZERO. WITH
COLD AIR ADVECTION AND A DECENT GRADIENT AHEAD OF THE ARCTIC
HIGH...NORTH WINDS COULD BECOME RATHER BREEZY SATURDAY. THE
BLOWING SNOW MODEL DOES NOT GIVE MUCH PROBABILITY DUE TO NO
FALLING SNOW AT THE TIME...BUT WILL HAVE TO WATCH WINDS ON
SATURDAY AS 925MB SPEEDS GET UP TO 25 KTS. THE WINDS WILL ALSO
KNOCK APPARENT TEMPS DOWN BELOW ADVISORY CRITERIA AT TIMES
ALTHOUGH TIMING IS STILL UNCERTAIN AT THIS POINT.
.LONG TERM...(SATURDAY NIGHT THROUGH THURSDAY)
ISSUED AT 300 AM CST FRI FEB 20 2015
SATURDAY NIGHT THROUGH SUNDAY NIGHT...CONDITIONS WILL REMAIN DRY
BUT COLD AS ARCTIC HIGH PRESSURE CONTINUES TO BUILD INTO THE AREA.
DEPENDING ON HOW MUCH WE CLEAR OUT...TEMPS SATURDAY NIGHT COULD
FALL BELOW 20 BELOW AND WITH SOME GRADIENT REMAINING...WIND CHILLS
MAY BE LOWER THEN 40 BELOW BY SUNDAY MORNING. THE SFC HIGH CENTER
BUILDING IN ON SUNDAY WILL CONTINUE WITH FRIGID TEMPS NOT RISING
INTO THE POSITIVE DIGITS. THE SFC HIGH WILL BEGIN TO SINK
SOUTHEASTWARD SUNDAY NIGHT AND WINDS WILL START PICKING UP WITH
SOME WARM AIR ADVECTION LATE IN THE NIGHT. TEMPS MAY START RISING
IN THE WEST...BUT NOT BEFORE BOTTOMING OUT IN THE TEENS BELOW
ZERO.
MONDAY THROUGH THURSDAY...THE EXTENDED BEGINS WITH A PAIR OF UPPER LEVEL
DISTURBANCES UPSTREAM IN CENTRAL CANADA. THE FIRST/WEAKER WAVE MAY
BRING A FEW FLURRIES TO THE AREA MONDAY AFTERNOON/EVENING...BUT A
BETTER CHANCE LOOKS TO COME LATER IN THE NIGHT WITH THE SECOND
WAVE. STILL...MOISTURE LOOKS LIMITED. SURFACE WINDS WILL BE
SOUTHWESTERLY ON MONDAY AHEAD OF A COLD FRONT ASSOCIATED WITH THE
SURFACE LOW PRESSURE SYSTEM. TEMPS AT 850 MB WARM CONSIDERABLY
FROM SUNDAY MORNING TO MONDAY MORNING... NEARLY 20C IN 30 HRS. THE
RESULT WILL BE HIGHS ABOUT 30 DEGREES WARMER ON MONDAY THAN ON
SUNDAY. THE COLD FRONT WILL THEN BARREL THROUGH THE AREA ON
TUESDAY MORNING. THE GOOD NEWS IS THAT IT IS EXPECTED TO BE A
GLANCING BLOW...WITH THE COLDEST AIR OFF TO THE EAST OVER FAR NE
MN AND LAKE SUPERIOR. THE BAD NEWS IS THAT STAGNANT COLD HIGH
PRESSURE WILL SET UP OVER THE NORTHERN PLANS TO END THE WEEK.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SATURDAY MORNING)
ISSUED AT 700 AM CST FRI FEB 20 2015
MVFR CIGS CONTINUE AT MOST TAF SITES ALTHOUGH A FEW SPOTS HAVE
BRIEFLY GONE UP TO VFR. THINK THAT THIS WILL BE SHORT LIVED AND
CIGS WILL BE IN THE 1200-2500 FT RANGE FOR TODAY AND THROUGH MOST
OF TONIGHT. SOME LINGERING LIGHT SNOW AT KBJI HAS TAPERED OFF AND
MOST OF THE FORECAST POINTS SHOULD REMAIN DRY. THERE IS A CHANCE
FOR SOME SNOW LATER IN THE PERIOD AROUND KDVL...SO PUT IN SOME
MVFR VIS AND -SN FOR A BRIEF PERIOD THIS EVENING. WINDS WILL BE
SHIFTING AROUND AS LOW PRESSURE MOVES ACROSS THE AREA...WITH THE
KDVL ALREADY GOING NORTHWESTERLY THIS MORNING. THE SHIFT WILL MOVE
EASTWARD THROUGHOUT THE MORNING...WITH SPEEDS AROUND 10 TO 15 KTS.
&&
.FGF WATCHES/WARNINGS/ADVISORIES...
ND...NONE.
MN...NONE.
&&
$$
UPDATE...DK
SHORT TERM...JR
LONG TERM...JR/KNUTSVIG
AVIATION...JR
AREA FORECAST DISCUSSION
NWS GRAND FORKS ND
701 AM CST FRI FEB 20 2015
.UPDATE...
ISSUED AT 700 AM CST FRI FEB 20 2015
MADE SOME TWEAKS TO CURRENT POPS AS ONLY THE EASTERN TIER IS
CURRENTLY SEEING SNOW. THINK THAT THE EASTERN SNOW WILL MOVE
FURTHER EAST EARLY THIS MORNING AND SNOW OVER WESTERN ND MAY CLIP
OUR WESTERN CWA. SOME LINGERING BLOWING SNOW ON THE EAST SIDE OF
THE RED RIVER SHOULD DIMINISH IN THE NEXT HOUR AS THE CENTER OF
THE SFC LOW BRINGS WINDS DOWN.
&&
.SHORT TERM...(TODAY THROUGH SATURDAY)
ISSUED AT 300 AM CST FRI FEB 20 2015
SNOW CHANCES TODAY AND TONIGHT WILL BE THE MAIN FORECAST
CHALLENGE...THEN WINDS TOMORROW.
NORTHWESTERLY FLOW ALOFT CONTINUES OVER THE NORTHERN PLAINS AND WV
LOOP SHOWS SEVERAL WEAK SHORTWAVES UPSTREAM. THE FIRST SHORTWAVE
CURRENTLY IS DIGGING INTO NORTHEASTERN SOUTH DAKOTA...AND THERE
HAS BEEN SOME LIGHT SNOW IN THE WARM AIR ADVECTION AHEAD OF THE
SFC LOW CURRENTLY ENTERING THE NORTHEASTERN CWA. THE LIGHT SNOW
HAS STARTED TO COME TO AN END ACROSS THE NORTHWESTERN
COUNTIES...SO THE TREND IN POPS TO PUSH HIGHEST PROBABILITIES OFF
TO THE EAST THIS MORNING SEEMS GOOD. THE RAP HAS THE NEXT WEAK
SHORTWAVES COMING THROUGH MAINLY ACROSS CENTRAL AND WESTERN
ND...WHICH FITS WITH CURRENT CANADIAN RADAR. MUCH OF THE SNOW FROM
THESE SHORTWAVES WILL REMAIN TO OUR WEST BUT CONTINUED TO KEEP
SOME LOW POPS IN OUR WESTERN COUNTIES IN CASE SOME LIGHT SNOW
CLIPS THAT AREA. WITH THE FIRST MORNING SHORTWAVE MOVING EAST AND
THE NEXT SHORTWAVES MAINLY FOCUSED ON THE FAR WESTERN TIER...THINK
THAT THERE WILL BE A PERIOD FOR THE CENTRAL CWA TODAY WHERE ONLY
LINGERING FLURRIES REMAINS. EVEN THOSE AREAS THAT GET ACCUMULATION
WILL SEE A HALF AN INCH AT MOST. THERE SHOULD BE ANOTHER LOW
CHANCE FOR ACCUMULATING SNOW AREAWIDE AS THE ARCTIC FRONT COMES
DOWN TONIGHT...BUT AGAIN IT WILL BE A DUSTING AT MOST.
TEMPS SHOULD BE FAIRLY MILD TODAY WITH GWINNER ALREADY AT 21
DEGREES AT 08Z. CONTINUED TO KEEP HIGHS IN THE TEENS IN THE NORTH
TO LOW 30S IN THE SOUTH. THE MILD TEMPS WILL END TONIGHT AS ARCTIC
AIR PLUNGES BACK SOUTH INTO THE CWA. WITH THE UPPER TROUGH DIGGING
DOWN OUT OF CANADA...ALL MODELS HAVE 850MB TEMPS BACK BELOW -20 C
FOR SATURDAY. CONTINUED TO KEEP HIGHS EITHER SIDE OF ZERO. WITH
COLD AIR ADVECTION AND A DECENT GRADIENT AHEAD OF THE ARCTIC
HIGH...NORTH WINDS COULD BECOME RATHER BREEZY SATURDAY. THE
BLOWING SNOW MODEL DOES NOT GIVE MUCH PROBABILITY DUE TO NO
FALLING SNOW AT THE TIME...BUT WILL HAVE TO WATCH WINDS ON
SATURDAY AS 925MB SPEEDS GET UP TO 25 KTS. THE WINDS WILL ALSO
KNOCK APPARENT TEMPS DOWN BELOW ADVISORY CRITERIA AT TIMES
ALTHOUGH TIMING IS STILL UNCERTAIN AT THIS POINT.
.LONG TERM...(SATURDAY NIGHT THROUGH THURSDAY)
ISSUED AT 300 AM CST FRI FEB 20 2015
SATURDAY NIGHT THROUGH SUNDAY NIGHT...CONDITIONS WILL REMAIN DRY
BUT COLD AS ARCTIC HIGH PRESSURE CONTINUES TO BUILD INTO THE AREA.
DEPENDING ON HOW MUCH WE CLEAR OUT...TEMPS SATURDAY NIGHT COULD
FALL BELOW 20 BELOW AND WITH SOME GRADIENT REMAINING...WIND CHILLS
MAY BE LOWER THEN 40 BELOW BY SUNDAY MORNING. THE SFC HIGH CENTER
BUILDING IN ON SUNDAY WILL CONTINUE WITH FRIGID TEMPS NOT RISING
INTO THE POSITIVE DIGITS. THE SFC HIGH WILL BEGIN TO SINK
SOUTHEASTWARD SUNDAY NIGHT AND WINDS WILL START PICKING UP WITH
SOME WARM AIR ADVECTION LATE IN THE NIGHT. TEMPS MAY START RISING
IN THE WEST...BUT NOT BEFORE BOTTOMING OUT IN THE TEENS BELOW
ZERO.
MONDAY THROUGH THURSDAY...THE EXTENDED BEGINS WITH A PAIR OF UPPER LEVEL
DISTURBANCES UPSTREAM IN CENTRAL CANADA. THE FIRST/WEAKER WAVE MAY
BRING A FEW FLURRIES TO THE AREA MONDAY AFTERNOON/EVENING...BUT A
BETTER CHANCE LOOKS TO COME LATER IN THE NIGHT WITH THE SECOND
WAVE. STILL...MOISTURE LOOKS LIMITED. SURFACE WINDS WILL BE
SOUTHWESTERLY ON MONDAY AHEAD OF A COLD FRONT ASSOCIATED WITH THE
SURFACE LOW PRESSURE SYSTEM. TEMPS AT 850 MB WARM CONSIDERABLY
FROM SUNDAY MORNING TO MONDAY MORNING... NEARLY 20C IN 30 HRS. THE
RESULT WILL BE HIGHS ABOUT 30 DEGREES WARMER ON MONDAY THAN ON
SUNDAY. THE COLD FRONT WILL THEN BARREL THROUGH THE AREA ON
TUESDAY MORNING. THE GOOD NEWS IS THAT IT IS EXPECTED TO BE A
GLANCING BLOW...WITH THE COLDEST AIR OFF TO THE EAST OVER FAR NE
MN AND LAKE SUPERIOR. THE BAD NEWS IS THAT STAGNANT COLD HIGH
PRESSURE WILL SET UP OVER THE NORTHERN PLANS TO END THE WEEK.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SATURDAY MORNING)
ISSUED AT 700 AM CST FRI FEB 20 2015
MVFR CIGS CONTINUE AT MOST TAF SITES ALTHOUGH A FEW SPOTS HAVE
BRIEFLY GONE UP TO VFR. THINK THAT THIS WILL BE SHORT LIVED AND
CIGS WILL BE IN THE 1200-2500 FT RANGE FOR TODAY AND THROUGH MOST
OF TONIGHT. SOME LINGERING LIGHT SNOW AT KBJI HAS TAPERED OFF AND
MOST OF THE FORECAST POINTS SHOULD REMAIN DRY. THERE IS A CHANCE
FOR SOME SNOW LATER IN THE PERIOD AROUND KDVL...SO PUT IN SOME
MVFR VIS AND -SN FOR A BRIEF PERIOD THIS EVENING. WINDS WILL BE
SHIFTING AROUND AS LOW PRESSURE MOVES ACROSS THE AREA...WITH THE
KDVL ALREADY GOING NORTHWESTERLY THIS MORNING. THE SHIFT WILL MOVE
EASTWARD THROUGHOUT THE MORNING...WITH SPEEDS AROUND 10 TO 15 KTS.
&&
.FGF WATCHES/WARNINGS/ADVISORIES...
ND...NONE.
MN...NONE.
&&
$$
UPDATE...JR
SHORT TERM...JR
LONG TERM...JR/KNUTSVIG
AVIATION...JR
AREA FORECAST DISCUSSION
NWS GRAND FORKS ND
300 AM CST FRI FEB 20 2015
.SHORT TERM...(TODAY THROUGH SATURDAY)
ISSUED AT 300 AM CST FRI FEB 20 2015
SNOW CHANCES TODAY AND TONIGHT WILL BE THE MAIN FORECAST
CHALLENGE...THEN WINDS TOMORROW.
NORTHWESTERLY FLOW ALOFT CONTINUES OVER THE NORTHERN PLAINS AND WV
LOOP SHOWS SEVERAL WEAK SHORTWAVES UPSTREAM. THE FIRST SHORTWAVE
CURRENTLY IS DIGGING INTO NORTHEASTERN SOUTH DAKOTA...AND THERE
HAS BEEN SOME LIGHT SNOW IN THE WARM AIR ADVECTION AHEAD OF THE
SFC LOW CURRENTLY ENTERING THE NORTHEASTERN CWA. THE LIGHT SNOW
HAS STARTED TO COME TO AN END ACROSS THE NORTHWESTERN
COUNTIES...SO THE TREND IN POPS TO PUSH HIGHEST PROBABILITIES OFF
TO THE EAST THIS MORNING SEEMS GOOD. THE RAP HAS THE NEXT WEAK
SHORTWAVES COMING THROUGH MAINLY ACROSS CENTRAL AND WESTERN
ND...WHICH FITS WITH CURRENT CANADIAN RADAR. MUCH OF THE SNOW FROM
THESE SHORTWAVES WILL REMAIN TO OUR WEST BUT CONTINUED TO KEEP
SOME LOW POPS IN OUR WESTERN COUNTIES IN CASE SOME LIGHT SNOW
CLIPS THAT AREA. WITH THE FIRST MORNING SHORTWAVE MOVING EAST AND
THE NEXT SHORTWAVES MAINLY FOCUSED ON THE FAR WESTERN TIER...THINK
THAT THERE WILL BE A PERIOD FOR THE CENTRAL CWA TODAY WHERE ONLY
LINGERING FLURRIES REMAINS. EVEN THOSE AREAS THAT GET ACCUMULATION
WILL SEE A HALF AN INCH AT MOST. THERE SHOULD BE ANOTHER LOW
CHANCE FOR ACCUMULATING SNOW AREAWIDE AS THE ARCTIC FRONT COMES
DOWN TONIGHT...BUT AGAIN IT WILL BE A DUSTING AT MOST.
TEMPS SHOULD BE FAIRLY MILD TODAY WITH GWINNER ALREADY AT 21
DEGREES AT 08Z. CONTINUED TO KEEP HIGHS IN THE TEENS IN THE NORTH
TO LOW 30S IN THE SOUTH. THE MILD TEMPS WILL END TONIGHT AS ARCTIC
AIR PLUNGES BACK SOUTH INTO THE CWA. WITH THE UPPER TROUGH DIGGING
DOWN OUT OF CANADA...ALL MODELS HAVE 850MB TEMPS BACK BELOW -20 C
FOR SATURDAY. CONTINUED TO KEEP HIGHS EITHER SIDE OF ZERO. WITH
COLD AIR ADVECTION AND A DECENT GRADIENT AHEAD OF THE ARCTIC
HIGH...NORTH WINDS COULD BECOME RATHER BREEZY SATURDAY. THE
BLOWING SNOW MODEL DOES NOT GIVE MUCH PROBABILITY DUE TO NO
FALLING SNOW AT THE TIME...BUT WILL HAVE TO WATCH WINDS ON
SATURDAY AS 925MB SPEEDS GET UP TO 25 KTS. THE WINDS WILL ALSO
KNOCK APPARENT TEMPS DOWN BELOW ADVISORY CRITERIA AT TIMES
ALTHOUGH TIMING IS STILL UNCERTAIN AT THIS POINT.
.LONG TERM...(SATURDAY NIGHT THROUGH THURSDAY)
ISSUED AT 300 AM CST FRI FEB 20 2015
SATURDAY NIGHT THROUGH SUNDAY NIGHT...CONDITIONS WILL REMAIN DRY
BUT COLD AS ARCTIC HIGH PRESSURE CONTINUES TO BUILD INTO THE AREA.
DEPENDING ON HOW MUCH WE CLEAR OUT...TEMPS SATURDAY NIGHT COULD
FALL BELOW 20 BELOW AND WITH SOME GRADIENT REMAINING...WIND CHILLS
MAY BE LOWER THEN 40 BELOW BY SUNDAY MORNING. THE SFC HIGH CENTER
BUILDING IN ON SUNDAY WILL CONTINUE WITH FRIGID TEMPS NOT RISING
INTO THE POSITIVE DIGITS. THE SFC HIGH WILL BEGIN TO SINK
SOUTHEASTWARD SUNDAY NIGHT AND WINDS WILL START PICKING UP WITH
SOME WARM AIR ADVECTION LATE IN THE NIGHT. TEMPS MAY START RISING
IN THE WEST...BUT NOT BEFORE BOTTOMING OUT IN THE TEENS BELOW
ZERO.
MONDAY THROUGH THURSDAY...THE EXTENDED BEGINS WITH A PAIR OF UPPER LEVEL
DISTURBANCES UPSTREAM IN CENTRAL CANADA. THE FIRST/WEAKER WAVE MAY
BRING A FEW FLURRIES TO THE AREA MONDAY AFTERNOON/EVENING...BUT A
BETTER CHANCE LOOKS TO COME LATER IN THE NIGHT WITH THE SECOND
WAVE. STILL...MOISTURE LOOKS LIMITED. SURFACE WINDS WILL BE
SOUTHWESTERLY ON MONDAY AHEAD OF A COLD FRONT ASSOCIATED WITH THE
SURFACE LOW PRESSURE SYSTEM. TEMPS AT 850 MB WARM CONSIDERABLY
FROM SUNDAY MORNING TO MONDAY MORNING... NEARLY 20C IN 30 HRS. THE
RESULT WILL BE HIGHS ABOUT 30 DEGREES WARMER ON MONDAY THAN ON
SUNDAY. THE COLD FRONT WILL THEN BARREL THROUGH THE AREA ON
TUESDAY MORNING. THE GOOD NEWS IS THAT IT IS EXPECTED TO BE A
GLANCING BLOW...WITH THE COLDEST AIR OFF TO THE EAST OVER FAR NE
MN AND LAKE SUPERIOR. THE BAD NEWS IS THAT STAGNANT COLD HIGH
PRESSURE WILL SET UP OVER THE NORTHERN PLANS TO END THE WEEK.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z FRIDAY NIGHT)
ISSUED AT 1139 PM CST THU FEB 19 2015
2-5SM IN LIGHT SNOW IN THE RRV INTO NW MN OVERNIGHT GRADUALLY
ENDING TO JUST SOME FLURRIES. CIGS AN ISSUE AS SHOULD GO DOWN INTO
THE MVFR RANGE 1500-2500FT AGL AND STAY THAT WAY THROUGH THE
BALANCE OF FRIDAY. SOUTH WINDS WITH GUSTS TO 25 KTS IN THE RRV WILL
TURN WEST AND NORTHWEST LATE TONIGHT INTO FRIDAY BUT REMAIN IN THE
10-15 KT RANGE.
&&
.FGF WATCHES/WARNINGS/ADVISORIES...
ND...NONE.
MN...NONE.
&&
$$
SHORT TERM...JR
LONG TERM...JR/KNUTSVIG
AVIATION...RIDDLE
AREA FORECAST DISCUSSION
NWS GRAND FORKS ND
1144 PM CST THU FEB 19 2015
.UPDATE...
ISSUED AT 1139 PM CST THU FEB 19 2015
NO ADDITIONAL CHANGES NEEDED. RADAR ESTIMATES FOR SNOW SHOW ONE
QUARTER TO THREE QUARTERS INCH ACROSS ERN ND WHICH SEEMS
REASONABLE. SNOW IS VERY FINE BUT BLOWING/DRIFTING AROUND SOME ESP
IN THE NRN VALLEY WHICH WAS ANTICIPATED. WINDS WILL DIMINISH LATER
TONIGHT.
UPDATE ISSUED AT 937 PM CST THU FEB 19 2015
SYSTEM MOVING THROUGH IS VERY UNIMPRESSIVE ON RADAR AND
OBSERVATIONS/WEBCAMS. A DUSTING IN DEVILS LAKE (MAYBE A FEW
TENTHS) BUT SNOW APPEARS VERY FINE. RAP MODEL DOESNT HAVE ANY
CONCENTRATED FRONTOGENSIS AND MAIN WARM ADV AT 850 IS WELL SOUTH
OF THE STATE. NET RESULT IS ENOUGH MOISTURE AND WEAK LIFT FOR
LIGHT PRECIP BUT NOTHING TO ENCOURAGE BIGGER SNOW FLAKE GROWTH. SO
TRIMMED SNOW TOTALS TO UNDER 1 INCH.
&&
.SHORT TERM...(THIS EVENING THROUGH FRIDAY NIGHT)
ISSUED AT 300 PM CST THU FEB 19 2015
THE MAIN CHALLENGE WILL BE LIGHT SNOW TONIGHT INTO FRI...THEN
BITTERLY COLD WIND CHILLS DEVELOPING SATURDAY INTO SUNDAY. MODELS
ARE IN GOOD AGREEMENT...SO CONFIDENCE IS FAIRLY HIGH WITH THIS
FORECAST.
FOR TONIGHT...A BAND OF LIGHT SNOW WILL SLOWLY MOVE FROM WEST TO
EAST WITHIN MID LEVEL WAA/ISENTROPIC LIFT. THERE IS A FAIRLY
CONCENTRATED AREA OF LIFT...BUT IT ONLY LASTS FROM 3-6HR. THIS
COUPLED WITH THE FACT THAT WE ARE IN FAST NW FLOW ALOFT...AND MID
LEVEL LAPSE RATES ARE FAIRLY STABLE...NOT EXPECTING MUCH IN THE
WAY OF PERSISTENT MESOSCALE BANDING. THE BEST CHANCE FOR AN INCH
OR SO SHOULD BE IN THE NORTH INTO NW MN. THERE WILL ALSO BE
SOUTHERLY WINDS THAT COULD SUSTAIN NEAR 20KT IN THE NORTHERN
VALLEY FROM 00-06Z...SO IF THIS OCCURS WITH LIGHT SNOW THEN PATCHY
BLOWING SNOW IS SUGGESTED WITH THE CANADIAN BLOWING SNOW MODEL.
THEREFORE...WILL ADD SOME PATCHY BLOWING SNOW IN THE NORTH VALLEY
FROM 00-06Z. TEMPS WILL SLOWLY RISE OVERNIGHT...ALTHOUGH WITH
SOUTHERLY WINDS IT WILL NOT FEEL WARM AT ALL...EVEN THOUGH WE
SHOULD REMAIN OUT OF WIND CHILL CRITERIA.
ON FRIDAY...A SFC LOW MOVES THROUGH IN THE MORNING WITH COLD
ADVECTION DEVELOPING BY AFTERNOON FROM NORTH TO SOUTH. THERE WILL
BE DEEP LAYERED SATURATION...AND SOME LIFTING NEAR SEVERAL
SHORTWAVES SO THE CONTINUATION OF LIGHT SNOW/SNOW SHOWERS IS
POSSIBLE. NOT EXPECTING MUCH ADDITIONAL ACCUMULATION THOUGH.
FOR FRI NIGHT...TEMPS WILL FALL BEHIND A STRONG COLD FRONT AND
THERE COULD BE SOME DRIFTING/PATCHY BLOWING SNOW IN OPEN AREAS.
WILL NOT MENTION FOR NOW SINCE THIS WILL DEPEND ON HOW STRONG
WINDS GET...BUT SOMETHING TO MONITOR. WIND CHILLS MAY FALL INTO
THE 25 TO 30 BELOW RANGE LATE AT NIGHT AND THAT WILL BE THE MAIN
HAZARD.
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 300 PM CST THU FEB 19 2015
FOR SAT THROUGH SUNDAY...A BITTERLY COLD AIRMASS WILL BE OVER THE
REGION WITH 925MB TEMPS DOWN TO AROUND -30C BY SAT AFTERNOON. THIS
COUPLED WITH STRONG NORTHERLY WINDS AROUND 15-20KT INTO SAT NIGHT
WILL PRODUCE BITTERLY COLD WIND CHILLS TO AT LEAST 40
BELOW...PERHAPS TO 45 BELOW LATE SAT NIGHT. NEEDLESS TO
SAY...WIND CHILL HEADLINES WILL BE NEEDED AS WE HEAD TOWARD THE
WEEKEND. THERE COULD EVEN BE SOME FLURRIES/SNOW SHOWERS ON SAT
ALONG WITH PATCHY BLOWING SNOW IN PRONE AREAS SAT NEAR ANY SNOW
SHOWERS...SO SOMETHING WE WILL MONITOR. ACTUAL AIR TEMPS WILL
LIKELY REMAIN BELOW ZERO SAT AND SUNDAY...WITH LOWS SAT NIGHT 20
TO 25 BELOW ALONG WITH DANGEROUS WIND CHILLS. IT SHOULD BE DRY
SUNDAY ALTHOUGH VERY COLD WITH ARCTIC HIGH PRESSURE MOVING
OVERHEAD.
FOR SUN NIGHT THROUGH THU...ARCTIC HIGH WILL MOVE OUT OF THE
REGION SUN NIGHT AND WESTERLY FLOW WILL PROVIDE A BRIEF WARM UP ON
MONDAY...WITH DAYTIME HIGHS IN THE 20S WEST AND MID TEENS EAST.
FOLLOWING THAT...A NORTHERLY UPPER FLOW PATTERN DOMINATES THE
WEEK...WITH AN UPPER HIGH OVER HUDSON BAY KICKING OFF A SHORT WAVE
THAT WILL ROTATE THROUGH OUR REGION MON NIGHT INTO TUE. THE
INCREASED CLOUD COVER WILL KEEP MODERATE OVERNIGHT TEMPS MON NIGHT
AND DAYTIME HIGHS TUESDAY IN THE MID TEENS. ANOTHER ARCTIC AIRMASS
DROPS IN FROM THE YUKON TERRITORY ON TUE NIGHT...BRINGING SUB ZERO
LOWS AND SINGLE DIGIT HIGHS BACK TO THE REGION FOR THE LATTER PART
OF THE WORK WEEK.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z FRIDAY NIGHT)
ISSUED AT 1139 PM CST THU FEB 19 2015
2-5SM IN LIGHT SNOW IN THE RRV INTO NW MN OVERNIGHT GRADUALLY
ENDING TO JUST SOME FLURRIES. CIGS AN ISSUE AS SHOULD GO DOWN INTO
THE MVFR RANGE 1500-2500FT AGL AND STAY THAT WAY THROUGH THE
BALANCE OF FRIDAY. SOUTH WINDS WITH GUSTS TO 25 KTS IN THE RRV WILL
TURN WEST AND NORTHWEST LATE TONIGHT INTO FRIDAY BUT REMAIN IN THE
10-15 KT RANGE.
&&
.FGF WATCHES/WARNINGS/ADVISORIES...
ND...NONE.
MN...NONE.
&&
$$
UPDATE...RIDDLE
SHORT TERM...DK
LONG TERM...DK/SPEICHER
AVIATION...RIDDLE
AREA FORECAST DISCUSSION
NWS NORMAN OK
1204 PM CST FRI FEB 20 2015
.AVIATION...
18Z...MOISTURE RETURN THIS MORNING IS RESULTING IN SOME
FOG...MAINLY IN WEST CENTRAL OKLAHOMA. HOWEVER...EXPECT SOME
IMPROVEMENT IN CEILINGS AND VISIBILITY THIS AFTERNOON ON
WESTERN EDGE OF CLOUD SHIELD. LATER THIS
AFTERNOON/EVENING...EXPECT WINDS WILL BACK WITH A BETTER CHANCE
FOR DRIZZLE AND SOME RESTRICTION TO VISIBILITY IN CENTRAL
OKLAHOMA. AS A SURFACE FRONTAL BOUNDARY STRENGTHENS ACROSS THE
AREA TONIGHT...PERHAPS THERE WILL BE A BETTER CHANCE OF VERY LOW
CLOUDS AND DRIZZLE. AS COLD AIR ADVECTION INCREASES AND SPREAD
SOUTHWARD TONIGHT...DRIZZLE AND VISIBILITY ISSUES WILL IMPROVE
THROUGH SATURDAY MORNING. FOR NOW...BETTER CHANCE FOR ELEVATED
STORMS...SHOULD REMAIN EAST OF ALL TAF SITES.
&&
.PREV DISCUSSION... /ISSUED 1106 AM CST FRI FEB 20 2015/
UPDATE...
MADE A FEW MINOR TWEAKS TO LOWER TEMPERATURES ACROSS THE
NORTH...WHERE NORTHEASTERLY WINDS CONTINUE. DONT EXPECT MUCH
WARMING IN THESE AREAS WITH OVERCAST SKIES. OTHERWISE...ADDED
MENTION OF PATCHY FOG AND DRIZZLE THROUGH THE DAY.
FORTUNATELY...IT LOOKS TO REMAIN WARM ENOUGH THAT ANY PRECIP THAT
FALLS WILL BE OF THE LIQUID VARIETY.
PREV DISCUSSION... /ISSUED 542 AM CST FRI FEB 20 2015/
AVIATION...
STRATUS CONTINUES TO SPREAD NORTH AND WEST MOVING INTO KOUN..
KOKC.. KPNC AND KLAW VERY SOON. WENT PRIMARILY WITH THE HRRR MODEL
ON HOW FAR WEST TO BRING THE STRATUS /VERY NEAR KHBR.. KCSM AND
KSPS AND NOT INTO KGAG AND KWWR/... BUT WILL BE WATCHING TRENDS.
THE TIMING OF THE STRATUS MOVING OUT OF THE AREA IS STILL VERY
MUCH IN QUESTION. HAVE BEEN LESS AGGRESSIVE WITH FOG DEVELOPMENT
GIVEN THE TIMING OF THE STRONGER SURFACE MOISTURE ADVECTION. A
COLD FRONT WILL MOVE THROUGH THE AREA THIS EVENING BRINGING A
BRISK NORTH WIND. GFS WOULD SUGGEST THAT THESE NORTH WINDS COULD
BE STRONGER THIS EVENING AND OVERNIGHT BEHIND THE COLD FRONT.
PREV DISCUSSION... /ISSUED 401 AM CST FRI FEB 20 2015/
DISCUSSION...
IT IS A COMPLEX WEATHER FORECAST THIS MORNING. MOISTURE ADVECTION
CONTINUES FROM THE SOUTHEAST THIS MORNING AND WITH THIS WILL BE A
CHANCE OF FOG/DRIZZLE THIS MORNING AND AT LEAST SOME LOW CHANCES
OF RAIN IN THE SOUTHEAST. TEMPERATURES WILL BE WARMER... ALTHOUGH
THE POTENTIAL ACROSS THE EASTERN HALF OF THE AREA WILL BE
MODERATED BY CLOUD COVER. DOWNSLOPE COMPONENT AND VERY WARM
TEMPERATURES IN THE LOW-LEVELS OF THE ATMOSPHERE WILL MAKE IT
QUITE WARM IN OUR TEXAS COUNTIES TODAY. COLD FRONT SWEEPS ACROSS
THE AREA TONIGHT WITH PRECIPITATION CHANCES CONTINUING... MAINLY
ACROSS THE EAST AND NORTH. SOME ELEVATED INSTABILITY DEVELOPS
GIVING A CHANCE OF THUNDERSTORMS OVERNIGHT ACROSS SOUTHERN AND
EASTERN OKLAHOMA. TEMPERATURES TOMORROW WILL STILL BE SEASONABLE
DESPITE THE FRONT OVERNIGHT.
A REINFORCING SHOT OF COLD AIR MOVES INTO THE AREA ON SUNDAY AND
REMINDS US THAT IT IS STILL WINTER. PRECIPITATION CHANCES PERSIST
INTO MONDAY WITH ENOUGH COLD AIR MOVING INTO THE AREA TO SUPPORT
WINTER PRECIPITATION. PRECIPITATION AMOUNTS MAY NOT BE TOO HIGH...
BUT WITH WINTER PRECIPITATION CHANCES SUNDAY AND MONDAY... MAY
HAVE SOME AREAS SLOWLY ACCUMULATE A COUPLE OF INCHES OF SNOW.
THERE IS ALSO SOME QUESTION IN THE MODELS ABOUT SUFFICIENT
HUMIDITY IN THE ICE CRYSTAL GROWTH LAYER AT TIMES TO KEEP FREEZING
RAIN IN THE DISCUSSION. RIGHT NOW WILL CONTINUE TO GO MOSTLY WITH
SNOW ALTHOUGH I HAVE MENTIONED FREEZING RAIN IN SOME AREAS ON
MONDAY. WILL CONTINUE TO WATCH TRENDS AS THIS DEVELOPS.
MOVING INTO MID-WEEK... FORECAST CONFIDENCE REMAINS LOW AS MEDIUM
RANGE MODELS DIFFER IN THE LOCATIONS OF THE LONGWAVE TROUGH IN THE
WEST AND THE WEAK RIDGE AHEAD OF IT SOMEWHERE IN THE ROCKIES OR
THE PLAINS. HOWEVER THERE IS REASONABLE AGREEMENT LATER IN THE
WEEK /JUST BEYOND THIS FORECAST PERIOD/ OF THE POTENTIAL OF MUCH
COLDER AIR SLIDING DOWN THE PLAINS.
&&
.PRELIMINARY POINT TEMPS/POPS...
OKLAHOMA CITY OK 40 54 25 33 / 20 10 20 30
HOBART OK 39 54 27 33 / 0 0 10 20
WICHITA FALLS TX 46 59 31 38 / 0 0 10 30
GAGE OK 33 48 20 27 / 10 10 50 40
PONCA CITY OK 35 50 21 29 / 40 10 20 20
DURANT OK 51 61 32 41 / 30 20 10 40
&&
.OUN WATCHES/WARNINGS/ADVISORIES...
OK...NONE.
TX...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS NORMAN OK
1106 AM CST FRI FEB 20 2015
.UPDATE...
MADE A FEW MINOR TWEAKS TO LOWER TEMPERATURES ACROSS THE
NORTH...WHERE NORTHEASTERLY WINDS CONTINUE. DONT EXPECT MUCH
WARMING IN THESE AREAS WITH OVERCAST SKIES. OTHERWISE...ADDED
MENTION OF PATCHY FOG AND DRIZZLE THROUGH THE DAY.
FORTUNATELY...IT LOOKS TO REMAIN WARM ENOUGH THAT ANY PRECIP THAT
FALLS WILL BE OF THE LIQUID VARIETY.
&&
.PREV DISCUSSION... /ISSUED 542 AM CST FRI FEB 20 2015/
AVIATION...
STRATUS CONTINUES TO SPREAD NORTH AND WEST MOVING INTO KOUN..
KOKC.. KPNC AND KLAW VERY SOON. WENT PRIMARILY WITH THE HRRR MODEL
ON HOW FAR WEST TO BRING THE STRATUS /VERY NEAR KHBR.. KCSM AND
KSPS AND NOT INTO KGAG AND KWWR/... BUT WILL BE WATCHING TRENDS.
THE TIMING OF THE STRATUS MOVING OUT OF THE AREA IS STILL VERY
MUCH IN QUESTION. HAVE BEEN LESS AGGRESSIVE WITH FOG DEVELOPMENT
GIVEN THE TIMING OF THE STRONGER SURFACE MOISTURE ADVECTION. A
COLD FRONT WILL MOVE THROUGH THE AREA THIS EVENING BRINGING A
BRISK NORTH WIND. GFS WOULD SUGGEST THAT THESE NORTH WINDS COULD
BE STRONGER THIS EVENING AND OVERNIGHT BEHIND THE COLD FRONT.
PREV DISCUSSION... /ISSUED 401 AM CST FRI FEB 20 2015/
DISCUSSION...
IT IS A COMPLEX WEATHER FORECAST THIS MORNING. MOISTURE ADVECTION
CONTINUES FROM THE SOUTHEAST THIS MORNING AND WITH THIS WILL BE A
CHANCE OF FOG/DRIZZLE THIS MORNING AND AT LEAST SOME LOW CHANCES
OF RAIN IN THE SOUTHEAST. TEMPERATURES WILL BE WARMER... ALTHOUGH
THE POTENTIAL ACROSS THE EASTERN HALF OF THE AREA WILL BE
MODERATED BY CLOUD COVER. DOWNSLOPE COMPONENT AND VERY WARM
TEMPERATURES IN THE LOW-LEVELS OF THE ATMOSPHERE WILL MAKE IT
QUITE WARM IN OUR TEXAS COUNTIES TODAY. COLD FRONT SWEEPS ACROSS
THE AREA TONIGHT WITH PRECIPITATION CHANCES CONTINUING... MAINLY
ACROSS THE EAST AND NORTH. SOME ELEVATED INSTABILITY DEVELOPS
GIVING A CHANCE OF THUNDERSTORMS OVERNIGHT ACROSS SOUTHERN AND
EASTERN OKLAHOMA. TEMPERATURES TOMORROW WILL STILL BE SEASONABLE
DESPITE THE FRONT OVERNIGHT.
A REINFORCING SHOT OF COLD AIR MOVES INTO THE AREA ON SUNDAY AND
REMINDS US THAT IT IS STILL WINTER. PRECIPITATION CHANCES PERSIST
INTO MONDAY WITH ENOUGH COLD AIR MOVING INTO THE AREA TO SUPPORT
WINTER PRECIPITATION. PRECIPITATION AMOUNTS MAY NOT BE TOO HIGH...
BUT WITH WINTER PRECIPITATION CHANCES SUNDAY AND MONDAY... MAY
HAVE SOME AREAS SLOWLY ACCUMULATE A COUPLE OF INCHES OF SNOW.
THERE IS ALSO SOME QUESTION IN THE MODELS ABOUT SUFFICIENT
HUMIDITY IN THE ICE CRYSTAL GROWTH LAYER AT TIMES TO KEEP FREEZING
RAIN IN THE DISCUSSION. RIGHT NOW WILL CONTINUE TO GO MOSTLY WITH
SNOW ALTHOUGH I HAVE MENTIONED FREEZING RAIN IN SOME AREAS ON
MONDAY. WILL CONTINUE TO WATCH TRENDS AS THIS DEVELOPS.
MOVING INTO MID-WEEK... FORECAST CONFIDENCE REMAINS LOW AS MEDIUM
RANGE MODELS DIFFER IN THE LOCATIONS OF THE LONGWAVE TROUGH IN THE
WEST AND THE WEAK RIDGE AHEAD OF IT SOMEWHERE IN THE ROCKIES OR
THE PLAINS. HOWEVER THERE IS REASONABLE AGREEMENT LATER IN THE
WEEK /JUST BEYOND THIS FORECAST PERIOD/ OF THE POTENTIAL OF MUCH
COLDER AIR SLIDING DOWN THE PLAINS.
&&
.PRELIMINARY POINT TEMPS/POPS...
OKLAHOMA CITY OK 55 40 54 25 / 20 20 10 20
HOBART OK 64 39 54 27 / 10 0 0 10
WICHITA FALLS TX 71 46 59 31 / 10 0 0 10
GAGE OK 55 33 48 20 / 0 10 10 50
PONCA CITY OK 44 35 50 21 / 30 40 10 20
DURANT OK 58 51 61 32 / 40 30 20 10
&&
.OUN WATCHES/WARNINGS/ADVISORIES...
OK...NONE.
TX...NONE.
&&
$$
84/06
AREA FORECAST DISCUSSION...UPDATED
NWS NORMAN OK
542 AM CST FRI FEB 20 2015
.AVIATION...
STRATUS CONTINUES TO SPREAD NORTH AND WEST MOVING INTO KOUN..
KOKC.. KPNC AND KLAW VERY SOON. WENT PRIMARILY WITH THE HRRR MODEL
ON HOW FAR WEST TO BRING THE STRATUS /VERY NEAR KHBR.. KCSM AND
KSPS AND NOT INTO KGAG AND KWWR/... BUT WILL BE WATCHING TRENDS.
THE TIMING OF THE STRATUS MOVING OUT OF THE AREA IS STILL VERY
MUCH IN QUESTION. HAVE BEEN LESS AGGRESSIVE WITH FOG DEVELOPMENT
GIVEN THE TIMING OF THE STRONGER SURFACE MOISTURE ADVECTION. A
COLD FRONT WILL MOVE THROUGH THE AREA THIS EVENING BRINGING A
BRISK NORTH WIND. GFS WOULD SUGGEST THAT THESE NORTH WINDS COULD
BE STRONGER THIS EVENING AND OVERNIGHT BEHIND THE COLD FRONT.
&&
.PREV DISCUSSION... /ISSUED 401 AM CST FRI FEB 20 2015/
DISCUSSION...
IT IS A COMPLEX WEATHER FORECAST THIS MORNING. MOISTURE ADVECTION
CONTINUES FROM THE SOUTHEAST THIS MORNING AND WITH THIS WILL BE A
CHANCE OF FOG/DRIZZLE THIS MORNING AND AT LEAST SOME LOW CHANCES
OF RAIN IN THE SOUTHEAST. TEMPERATURES WILL BE WARMER... ALTHOUGH
THE POTENTIAL ACROSS THE EASTERN HALF OF THE AREA WILL BE
MODERATED BY CLOUD COVER. DOWNSLOPE COMPONENT AND VERY WARM
TEMPERATURES IN THE LOW-LEVELS OF THE ATMOSPHERE WILL MAKE IT
QUITE WARM IN OUR TEXAS COUNTIES TODAY. COLD FRONT SWEEPS ACROSS
THE AREA TONIGHT WITH PRECIPITATION CHANCES CONTINUING... MAINLY
ACROSS THE EAST AND NORTH. SOME ELEVATED INSTABILITY DEVELOPS
GIVING A CHANCE OF THUNDERSTORMS OVERNIGHT ACROSS SOUTHERN AND
EASTERN OKLAHOMA. TEMPERATURES TOMORROW WILL STILL BE SEASONABLE
DESPITE THE FRONT OVERNIGHT.
A REINFORCING SHOT OF COLD AIR MOVES INTO THE AREA ON SUNDAY AND
REMINDS US THAT IT IS STILL WINTER. PRECIPITATION CHANCES PERSIST
INTO MONDAY WITH ENOUGH COLD AIR MOVING INTO THE AREA TO SUPPORT
WINTER PRECIPITATION. PRECIPITATION AMOUNTS MAY NOT BE TOO HIGH...
BUT WITH WINTER PRECIPITATION CHANCES SUNDAY AND MONDAY... MAY
HAVE SOME AREAS SLOWLY ACCUMULATE A COUPLE OF INCHES OF SNOW.
THERE IS ALSO SOME QUESTION IN THE MODELS ABOUT SUFFICIENT
HUMIDITY IN THE ICE CRYSTAL GROWTH LAYER AT TIMES TO KEEP FREEZING
RAIN IN THE DISCUSSION. RIGHT NOW WILL CONTINUE TO GO MOSTLY WITH
SNOW ALTHOUGH I HAVE MENTIONED FREEZING RAIN IN SOME AREAS ON
MONDAY. WILL CONTINUE TO WATCH TRENDS AS THIS DEVELOPS.
MOVING INTO MID-WEEK... FORECAST CONFIDENCE REMAINS LOW AS MEDIUM
RANGE MODELS DIFFER IN THE LOCATIONS OF THE LONGWAVE TROUGH IN THE
WEST AND THE WEAK RIDGE AHEAD OF IT SOMEWHERE IN THE ROCKIES OR
THE PLAINS. HOWEVER THERE IS REASONABLE AGREEMENT LATER IN THE
WEEK /JUST BEYOND THIS FORECAST PERIOD/ OF THE POTENTIAL OF MUCH
COLDER AIR SLIDING DOWN THE PLAINS.
&&
.PRELIMINARY POINT TEMPS/POPS...
OKLAHOMA CITY OK 57 40 54 25 / 20 20 10 20
HOBART OK 63 39 54 27 / 10 0 0 10
WICHITA FALLS TX 73 46 59 31 / 10 0 0 10
GAGE OK 61 33 48 20 / 0 10 10 50
PONCA CITY OK 47 35 50 21 / 30 40 10 20
DURANT OK 61 51 61 32 / 40 30 20 10
&&
.OUN WATCHES/WARNINGS/ADVISORIES...
OK...NONE.
TX...NONE.
&&
$$
99/99/01
AREA FORECAST DISCUSSION...UPDATED
NWS ABERDEEN SD
140 PM CST FRI FEB 20 2015
.UPDATE...
FRONTAL BOUNDARY JUST NORTH OF THE CWA NOW...WITH A PREFRONTAL
AREA OF PRECIPITATION TRACKING OVER THE NORTHEAST. THE
PRECIPITATION HAS BEEN MOSTLY SNOW...BUT MAY BE A LITTLE FREEZING
PRECIPITATION MIXED IN AS WELL. ANOTHER AREA APPROACHING FROM THE
NORTHWEST...BUT SOME QUESTION AS TO WHETHER OR NOT COOLING WILL
HAVE BEGUN BEFORE IT GETS HERE. WILL LEAVE LIQUID PRECIPITATION
ACROSS THE WEST AND SNOW ACROSS THE EAST FOR NOW...BUT
ACCUMULATIONS SHOULD BE MINIMAL.
SEE UPDATED AVIATION DISCUSSION BELOW.
&&
.SHORT TERM...TODAY THROUGH SUNDAY
AS OF 9Z...A SURFACE LOW PRESSURE SYSTEM IS LOCATED OVER NORTHERN
NORTH DAKOTA. THE WARM FRONT ASSOCIATED WITH THE LOW PRESSURE IS
ALONG THE MISSOURI RIVER. THE WARM FRONT WILL PUSH EAST TODAY
ALLOWING FOR ABOVE NORMAL TEMPERATURES TO SPREAD ACROSS THE CWA.
THE PAST FEW RUNS OF THE HRRR AND RAPID REFRESH...PLUS THE NSSL
WRF ALL SUPPORT HIGHS IN THE MID 40S TO THE MID 50S FOR NORTH
CENTRAL AND CENTRAL SOUTH DAKOTA. COOLER TEMPERATURES ARE EXPECTED
IN NORTHEASTERN SOUTH DAKOTA AND WESTERN MINNESOTA.
A COLD FRONT...CURRENTLY OVER SOUTHERN CANADA...WILL SLIDE
SOUTHWARD ACROSS THE CWA LATER THIS AFTERNOON. LIGHT PRECIPITATION
IS POSSIBLE ALONG THIS FRONT...HOWEVER CHANCES APPEARS BETTER POST
FRONTAL...OR WITH THE CAA. PRECIPITATION AMOUNTS SHOULD BE RATHER
LIGHT. COLD AIR ADVECTION...THANKS TO AN ARCTIC HIGH
PRESSURE...WILL CONTINUE THROUGH SUNDAY WITH TEMPERATURES BECOMING
PROGRESSIVELY COLDER. HIGHS ON SATURDAY WILL RANGE FROM THE SINGLE
DIGITS...TO THE MID 20S. HIGHS BY SUNDAY WILL LIKELY RANGE FROM
THE SINGLE DIGITS BELOW ZERO...IN NORTHEASTERN SOUTH DAKOTA...TO
THE MID TEENS IN CENTRAL SOUTH DAKOTA.
.LONG TERM...SUNDAY NIGHT THROUGH THURSDAY
VERY GOOD AGREEMENT WITH ALL OF THE MODELS IN THE LONG TERM. THE
PERIOD BEGINS WITH ARCTIC HIGH PRESSURE CENTERED OVER EASTERN SD
BUILDING SOUTHEAST THROUGH SUNDAY NIGHT. AFTER A COLD SUNDAY
NIGHT...SOUTHWEST WINDS ON THE BACKSIDE OF THIS SURFACE HIGH WILL
BRING IN WARMER AIR WITH TEMPERATURES WARMING UP TO NEAR NORMAL BY
LATE MONDAY AFTERNOON. MONDAY NIGHT WILL BE MILD WITH PACIFIC AIR
MOVING ACROSS THE REGION ON WEST WINDS. TUESDAY WILL REMAIN NEAR
NORMAL FOR HIGHS WITH A TROUGH COMING THROUGH AS WINDS TURN
NORTHWEST AND INCREASE. AN ARCTIC BOUNDARY WILL THEN PUSH THROUGH
LATE TUESDAY AFTERNOON AND EVENING. ARCTIC AIR WILL REMAIN OVER
THE REGION THROUGH THURSDAY WITH MUCH BELOW NORMAL TEMPERATURES.
THE MODELS ALL SHOW A CLIPPER SYSTEM DROPPING SOUTHEAST ALONG THE
ARCTIC BOUNDARY LATE TUESDAY NIGHT THROUGH WEDNESDAY NIGHT. AT
THIS TIME THEY ALL SHOW SOME SNOW WITH THIS SYSTEM MAINLY ACROSS
THE WESTERN CWA. THUS...INCREASED POPS SOME AND MAY HAVE TO
INCREASE THEM MORE IN LATER FORECASTS.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON)
ISSUED AT 138 PM CST FRI FEB 20 2015
A MIX OF VFR/MVFR CIGS ARE POSSIBLE FOR ALL TAF LOCATIONS...WITH A
TREND TOWARDS IFR...WHICH WILL LIKELY PERSIST THROUGH THE TAF
PERIOD. VSBY WILL BE PREDOMINANTLY VFR BUT CANT RULE OUT SOME
SHORT DURATION MVFR/IFR REDUCTIONS DUE TO SNOW. WINDS WILL SHIFT
FROM WEST/SOUTHWEST TO NORTHERLY AS WELL.
&&
.ABR WATCHES/WARNINGS/ADVISORIES...
SD...NONE.
MN...NONE.
&&
$$
UPDATE...PARKIN
SHORT TERM...SD
LONG TERM...MOHR
AVIATION...CONNELLY
AREA FORECAST DISCUSSION
NWS SIOUX FALLS SD
1141 AM CST FRI FEB 20 2015
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 408 AM CST FRI FEB 20 2015
SNOWFALL WHICH HAS BEEN SCARCE SO FAR OVERNIGHT WILL GET ONE LAST
CHANCE THROUGH THE REMAINDER OF THE OVERNIGHT AS UPPER WAVE SHEARS
SOUTHEAST FROM NORTHEAST SOUTH DAKOTA INTO SOUTHERN MINNESOTA. WHILE
MARKEDLY BETTER CHANCE JUST NORTHEAST OF THE CWA...HAVE INCLUDED
SMALLER CHANCE POPS FOR THE REST OF THE OVERNIGHT TO COVER TIMING OF
WAVE. FOLLOWING THIS WAVE...OTHER THAN THE INCREASINGLY SHALLOW
LOWER LEVEL WARM ADVECTION...PRETTY MUCH SET UP FOR A PERIOD OF
FAIRLY LACKLUSTER FORCING BEHIND THIS WAVE THROUGH THE AFTERNOON...
WITH THE EVENTUAL NORTH-SOUTH SPLIT TO UPSTREAM SYSTEM PUSHING A
FRONTAL BOUNDARY INTO THE NORTHERN CWA DURING THE LATER AFTERNOON.
SEVERAL MODELS INDICATE THAT THERE WILL BE SOME LIGHT QPF NEAR THIS
BOUNDARY DURING THE LATER AFTERNOON...BUT MUCH OF THIS LOOKS TO BE A
RESULT OF SURFACE BASED DESTABILIZATION RATHER THAN ANY DYNAMICAL
LIFT FORCING WHICH REMAINS MINIMAL THROUGH THE DAY.
IT WILL BE SIGNIFICANTLY WARMER TODAY ACROSS THE AREA...WITH THE
GREATEST CHALLENGE TO THIS WARMING TO BE THE EXTENT OF CLOUDINESS
GIVEN A RELATIVE LACK OF SNOW COVER. BEHIND THE EARLY MORNING UPPER
WAVE...EXPECT MORE WIDESPREAD LOWER CLOUDINESS ACROSS CENTRAL NORTH
DAKOTA TO CONTINUE TO SURGE SOUTHEASTWARD...AS IS CURRENTLY UNDERWAY
IN NORTH CENTRAL SD. RAP SEEMS TO HAVE AN ADEQUATE HANDLE ON THE
SHORT TERM BEHAVIOR OF THE CLOUD FIELDS...AND HAVE GENERALLY USED AS
A GUIDE TO TRANSLATE THE LOWER CLOUDS SOUTH AND EAST THROUGH THE
DAY...HOLDING TOUGH MUCH OF THE DAY ACROSS SW MN AND INTO PARTS OF
NW IA. GIVEN TEMPS IN THE UPPER 20S TO AROUND 30 UNDER THE INCREASED
CLOUDS...AM HESITANT TO GO QUITE AS COOL AS SEVERAL SOLUTIONS
SUGGEST...AND HAVE BASED OFF A MODIFIED RAP SURFACE THERMAL FIELD
THROUGH THE DAY. THERE WILL AT LEAST BE A FAIR AMOUNT OF HIGHER
CLOUDS AROUND IN OTHER AREAS SOUTHWEST OF THE LOWER CLOUDS...WHERE
WHICH IT WILL LIKELY PUSH 50 DEGREES ON MIXING ALONE IN THE WESTERN
MISSOURI VALLEY...AND EVEN A MODEST RIDE INTO THE LOWER 30S EXPECTED
IN SW MN.
LOWER LEVEL COLD AIR WILL BEGIN TO SURGE SOUTHWARD...ESPECIALLY
THROUGH THE LATTER HALF OF THE NIGHT...WITH FAIRLY STRONG
ISALLOBARIC RISES SET TO DRIVE AN INCREASING NORTHERLY WIND THROUGH
THE NIGHT. THIS TYPE OF SET UP ALMOST ALWAYS HAS THE COOLING COMING
IN A MORE FORCEFUL WAY...AND HAVE PUSHED THE COOLING RATES UP ABOUT
3 HOURS LATER TONIGHT AND EARLY SATURDAY MORNING THAN EVEN SOME OF
THE COOLER RAW GUIDANCE. GRADUALLY...THERMAL FIELDS BECOME MORE
FAVORABLE FOR SHALLOW FORCED PRECIPITATION BEHIND THE FRONTAL
BOUNDARY. AT THIS TIME...HAVE PRECLUDED ANY MENTION OF MEASURABLE
SNOWFALL /OR POTENTIALLY RAINFALL EARLY EVENING IN THE WEST/...BUT
DID WORK IN A GRADUAL NORTH TO SOUTH SPREAD FOR ISOLATED TO
SCATTERED FLURRIES. WIND CHILLS BY MORNING WILL RETURN BELOW ZERO
FROM EAST CENTRAL SD THROUGH MUCH OF SW MN.
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 408 AM CST FRI FEB 20 2015
FOR THE WEEKEND...THE FORECAST CONCERN CENTERS ON THE ARCTIC AIR
MOVING IN. THE COLD AIR BEHIND THE FRONT THAT MOVES THROUGH
TONIGHT WILL CONTINUE TO SURGE SOUTHWARD ON SATURDAY. AS A RESULT
EXPECT TEMPERATURES TO BASICALLY BE STEADY OR SLOWLY FALL THROUGH
THE DAY WITH HIGHS LIKELY TO BE AROUND SUNRISE. BY EVENING
TEMPERATURES WILL RANGE FROM THE SINGLE DIGITS ABOVE ZERO NORTH OF
I90 TO THE LOWER 20S IN THE MISSOURI VALLEY. NORTHWEST WINDS WILL
BE GUSTING AS HIGH AS 30 MPH BEHIND THE FRONT AND THIS WILL
PRODUCE WIND CHILLS BELOW ZERO NORTH OF AND EAST OF THE JAMES AND
MISSOURI VALLEY THROUGHOUT THE DAY.
NORTHWEST WINDS ARE EXPECTED TO REMAIN BETWEEN 10 AND 20 MPH
SATURDAY NIGHT AND MUCH OF SUNDAY. WITH LOWS EXPECTED TO BE AT OR
BELOW ZERO IN ALL BUT THE MISSOURI VALLEY SATURDAY NIGHT...WIND
CHILLS WILL RANGE FROM -15 TO -30 LATE SATURDAY NIGHT AND SUNDAY
MORNING WITH THE COLDEST WIND CHILLS IN SOUTHWEST MINNESOTA.
DESPITE SUNSHINE AND LITTLE SNOW COVER...HIGHS SUNDAY WILL
GENERALLY BE IN THE SINGLE DIGITS ABOVE ZERO. HIGH PRESSURE WILL
MOVE FROM MINNESOTA INTO WESTERN ILLINOIS ON SUNDAY NIGHT. WINDS
WILL DECREASE FAIRLY RAPIDLY AFTER DARK AND THEN AS THE HIGH MOVES
THROUGH IOWA...TURN TO THE SOUTH AND BEGIN TO
INCREASE...ESPECIALLY WEST OF I29. WITH CLEAR SKIES AND LIGHT
WINDS...MOST LOCATIONS WILL FALL IN THE EVENING BUT TEMPERATURES
WILL BECOME STEADY OR EVEN RISE A FEW DEGREES AFTER MIDNIGHT. AS A
RESULT...LOWS WILL BE IN THE SINGLE DIGITS BELOW ZERO EAST OF THE
JAMES RIVER AND IN THE SINGLE DIGITS ABOVE ZERO WEST OF THE JAMES
RIVER.
IN THE EXTENDED...MONDAY THROUGH THURSDAY...IT WILL BE A CONTRAST
IN REGIMES...WITH NEAR NORMAL TO ABOVE NORMAL TEMPERATURES MONDAY
AND TUESDAY AND BELOW NORMAL TEMPERATURES WEDNESDAY AND THURSDAY
AS ANOTHER SURGE OF ARCTIC AIR MOVES INTO THE AREA. THERE IS
SURPRISINGLY LITTLE DIFFERENCE IN THE OVERALL PATTERN BETWEEN THE
ECMWF...GFS AND THE GFS ENSEMBLE. SO CONFIDENCE IS HIGH IN TERMS
OF THE TEMPERATURE TRENDS. THE ONLY UNCERTAINTY RESTS WITH THE
CHANCE OF SNOW ON WEDNESDAY AND WEDNESDAY NIGHT. THE ECMWF IS
WEAKER WITH THE SNOWFALL...BASICALLY EXTENDING FROM WESTERN NORTH
DAKOTA...THROUGH MUCH OF SOUTH DAKOTA...AND INTO EASTERN NEBRASKA
AND FAR WESTERN IOWA. THE GFS IS GENERALLY IN THE SAME AREA BUT
FASTER AND WITH MORE SNOWFALL. WITH AN ARCTIC AIR MASS IN
PLACES...MOISTURE WILL BE LIMITED SO A SOLUTION CLOSER TO THE
ECMWF SEEMS MORE LIKELY AT THIS POINT.
ON MONDAY WILL SEE A GRADUAL WARMING AS WINDS INCREASE OUT OF THE
SOUTHWEST. BY AFTERNOON IT COULD BECOME QUITE BREEZY AND WITH
SKIES EXPECTED TO BE PARTLY TO MOSTLY SUNNY...THE ATMOSPHERE
SHOULD BECOME MORE MIXED THROUGH THE DAY. AS A RESULT...EXPECT TO
SEE QUITE A DIURNAL RANGE WITH HIGHS WARMING 25 TO 30 DEGREES INTO
THE MID 20S TO MID 30S. WITH WEST TO NORTHWEST FLOW CONTINUING
MONDAY NIGHT...EXPECT TEMPERATURES TO REMAIN IN THE 20S. TUESDAY
WILL SEE THE PASSAGE OF THE NEXT ARCTIC FRONT. WITH STRONG
NORTHWEST WINDS BEHIND THE FRONT...EXPECT THE AIR ALOFT TO MIX TO
THE SURFACE HELPING TEMPERATURES TO RISE BACK ABOVE FREEZING
BEFORE THE REAL COLD AIR MOVES BACK IN TUESDAY NIGHT. HIGHS
WEDNESDAY WILL BE IN THE TEENS AND 20S WITH EVEN COLDER
TEMPERATURES EXPECTED THURSDAY. WITH THE COLD AIR IN CANADA WOULD
NOT BE SURPRISED IF THIS AIR MASS ENDS UP A FEW DEGREES COLDER
THAN FORECAST BUT WILL WAIT UNTIL THERE IS MORE CONFIDENCE IN THE
MAGNITUDE OF THE COLD AIR BEFORE LOWERING TEMPERATURES EVEN MORE.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON)
ISSUED AT 1141 AM CST FRI FEB 20 2015
MVFR CEILINGS WILL ERODE OVER THE I 29 CORRIDOR THROUGH THE
AFTERNOON HOURS. THESE CEILINGS ARE CURRENTLY AFFECTING THE KFSD
TAF SITE. THERE ARE NO VISIBILITY RESTRICTIONS. TONIGHT...ANOTHER
ARCTIC COLD FRONT WILL MOVE SOUTHWARD...WITH BOTH THE NAM AND GFS
SHOWING STRATUS COMING DOWN BEHIND THE FRONT. THEREFORE KEPT THE
MVFR MENTION GOING IN THE TAF SITES.
&&
.FSD WATCHES/WARNINGS/ADVISORIES...
SD...NONE.
MN...NONE.
IA...NONE.
NE...NONE.
&&
$$
SHORT TERM...CHAPMAN
LONG TERM...SCHUMACHER
AVIATION...MJ
AREA FORECAST DISCUSSION...UPDATED
NWS ABERDEEN SD
1130 AM CST FRI FEB 20 2015
.UPDATE...
FRONTAL BOUNDARY JUST NORTH OF THE CWA NOW...WITH A PREFRONTAL
AREA OF PRECIPITATION TRACKING OVER THE NORTHEAST. THE
PRECIPITATION HAS BEEN MOSTLY SNOW...BUT MAY BE A LITTLE FREEZING
PRECIPITATION MIXED IN AS WELL. ANOTHER AREA APPROACHING FROM THE
NORTHWEST...BUT SOME QUESTION AS TO WHETHER OR NOT COOLING WILL
HAVE BEGUN BEFORE IT GETS HERE. WILL LEAVE LIQUID PRECIPITATION
ACROSS THE WEST AND SNOW ACROSS THE EAST FOR NOW...BUT
ACCUMULATIONS SHOULD BE MINIMAL.
SEE UPDATED AVIATION DISCUSSION BELOW.
&&
.PREVIOUS DISCUSSION...
.SHORT TERM...TODAY THROUGH SUNDAY
AS OF 9Z...A SURFACE LOW PRESSURE SYSTEM IS LOCATED OVER NORTHERN
NORTH DAKOTA. THE WARM FRONT ASSOCIATED WITH THE LOW PRESSURE IS
ALONG THE MISSOURI RIVER. THE WARM FRONT WILL PUSH EAST TODAY
ALLOWING FOR ABOVE NORMAL TEMPERATURES TO SPREAD ACROSS THE CWA.
THE PAST FEW RUNS OF THE HRRR AND RAPID REFRESH...PLUS THE NSSL
WRF ALL SUPPORT HIGHS IN THE MID 40S TO THE MID 50S FOR NORTH
CENTRAL AND CENTRAL SOUTH DAKOTA. COOLER TEMPERATURES ARE EXPECTED
IN NORTHEASTERN SOUTH DAKOTA AND WESTERN MINNESOTA.
A COLD FRONT...CURRENTLY OVER SOUTHERN CANADA...WILL SLIDE
SOUTHWARD ACROSS THE CWA LATER THIS AFTERNOON. LIGHT PRECIPITATION
IS POSSIBLE ALONG THIS FRONT...HOWEVER CHANCES APPEARS BETTER POST
FRONTAL...OR WITH THE CAA. PRECIPITATION AMOUNTS SHOULD BE RATHER
LIGHT. COLD AIR ADVECTION...THANKS TO AN ARCTIC HIGH
PRESSURE...WILL CONTINUE THROUGH SUNDAY WITH TEMPERATURES BECOMING
PROGRESSIVELY COLDER. HIGHS ON SATURDAY WILL RANGE FROM THE SINGLE
DIGITS...TO THE MID 20S. HIGHS BY SUNDAY WILL LIKELY RANGE FROM
THE SINGLE DIGITS BELOW ZERO...IN NORTHEASTERN SOUTH DAKOTA...TO
THE MID TEENS IN CENTRAL SOUTH DAKOTA.
.LONG TERM...SUNDAY NIGHT THROUGH THURSDAY
VERY GOOD AGREEMENT WITH ALL OF THE MODELS IN THE LONG TERM. THE
PERIOD BEGINS WITH ARCTIC HIGH PRESSURE CENTERED OVER EASTERN SD
BUILDING SOUTHEAST THROUGH SUNDAY NIGHT. AFTER A COLD SUNDAY
NIGHT...SOUTHWEST WINDS ON THE BACKSIDE OF THIS SURFACE HIGH WILL
BRING IN WARMER AIR WITH TEMPERATURES WARMING UP TO NEAR NORMAL BY
LATE MONDAY AFTERNOON. MONDAY NIGHT WILL BE MILD WITH PACIFIC AIR
MOVING ACROSS THE REGION ON WEST WINDS. TUESDAY WILL REMAIN NEAR
NORMAL FOR HIGHS WITH A TROUGH COMING THROUGH AS WINDS TURN
NORTHWEST AND INCREASE. AN ARCTIC BOUNDARY WILL THEN PUSH THROUGH
LATE TUESDAY AFTERNOON AND EVENING. ARCTIC AIR WILL REMAIN OVER
THE REGION THROUGH THURSDAY WITH MUCH BELOW NORMAL TEMPERATURES.
THE MODELS ALL SHOW A CLIPPER SYSTEM DROPPING SOUTHEAST ALONG THE
ARCTIC BOUNDARY LATE TUESDAY NIGHT THROUGH WEDNESDAY NIGHT. AT
THIS TIME THEY ALL SHOW SOME SNOW WITH THIS SYSTEM MAINLY ACROSS
THE WESTERN CWA. THUS...INCREASED POPS SOME AND MAY HAVE TO
INCREASE THEM MORE IN LATER FORECASTS.
&&
.AVIATION...
18Z TAFS FOR THE KABR...KATY...KPIR AND KMBG TERMINALS
A MIX OF VFR/MVFR CIGS ARE POSSIBLE FOR ALL TAF LOCATIONS...WITH A
TREND TOWARDS IFR...WHICH WILL LIKELY PERSIST THROUGH THE TAF
PERIOD. VSBY WILL BE PREDOMINANTLY VFR BUT CANT RULE OUT SOME
SHORT DURATION MVFR/IFR REDUCTIONS DUE TO SNOW. WINDS WILL SHIFT
FROM WEST/SOUTHWEST TO NORTHERLY AS WELL.
&&
.ABR WATCHES/WARNINGS/ADVISORIES...
SD...NONE.
MN...NONE.
&&
$$
UPDATE...PARKIN
SHORT TERM...SD
LONG TERM...MOHR
AVIATION...CONNELLY
WEATHER.GOV/ABERDEEN
AREA FORECAST DISCUSSION...UPDATED
NWS ABERDEEN SD
601 AM CST FRI FEB 20 2015
.UPDATE...
AVIATION DISCUSSION UPDATED BELOW.
&&
.SHORT TERM...TODAY THROUGH SUNDAY
AS OF 9Z...A SURFACE LOW PRESSURE SYSTEM IS LOCATED OVER NORTHERN
NORTH DAKOTA. THE WARM FRONT ASSOCIATED WITH THE LOW PRESSURE IS
ALONG THE MISSOURI RIVER. THE WARM FRONT WILL PUSH EAST TODAY
ALLOWING FOR ABOVE NORMAL TEMPERATURES TO SPREAD ACROSS THE CWA.
THE PAST FEW RUNS OF THE HRRR AND RAPID REFRESH...PLUS THE NSSL
WRF ALL SUPPORT HIGHS IN THE MID 40S TO THE MID 50S FOR NORTH
CENTRAL AND CENTRAL SOUTH DAKOTA. COOLER TEMPERATURES ARE EXPECTED
IN NORTHEASTERN SOUTH DAKOTA AND WESTERN MINNESOTA.
A COLD FRONT...CURRENTLY OVER SOUTHERN CANADA...WILL SLIDE
SOUTHWARD ACROSS THE CWA LATER THIS AFTERNOON. LIGHT PRECIPITATION
IS POSSIBLE ALONG THIS FRONT...HOWEVER CHANCES APPEARS BETTER POST
FRONTAL...OR WITH THE CAA. PRECIPITATION AMOUNTS SHOULD BE RATHER
LIGHT. COLD AIR ADVECTION...THANKS TO AN ARCTIC HIGH
PRESSURE...WILL CONTINUE THROUGH SUNDAY WITH TEMPERATURES BECOMING
PROGRESSIVELY COLDER. HIGHS ON SATURDAY WILL RANGE FROM THE SINGLE
DIGITS...TO THE MID 20S. HIGHS BY SUNDAY WILL LIKELY RANGE FROM
THE SINGLE DIGITS BELOW ZERO...IN NORTHEASTERN SOUTH DAKOTA...TO
THE MID TEENS IN CENTRAL SOUTH DAKOTA.
.LONG TERM...SUNDAY NIGHT THROUGH THURSDAY
VERY GOOD AGREEMENT WITH ALL OF THE MODELS IN THE LONG TERM. THE
PERIOD BEGINS WITH ARCTIC HIGH PRESSURE CENTERED OVER EASTERN SD
BUILDING SOUTHEAST THROUGH SUNDAY NIGHT. AFTER A COLD SUNDAY
NIGHT...SOUTHWEST WINDS ON THE BACKSIDE OF THIS SURFACE HIGH WILL
BRING IN WARMER AIR WITH TEMPERATURES WARMING UP TO NEAR NORMAL BY
LATE MONDAY AFTERNOON. MONDAY NIGHT WILL BE MILD WITH PACIFIC AIR
MOVING ACROSS THE REGION ON WEST WINDS. TUESDAY WILL REMAIN NEAR
NORMAL FOR HIGHS WITH A TROUGH COMING THROUGH AS WINDS TURN
NORTHWEST AND INCREASE. AN ARCTIC BOUNDARY WILL THEN PUSH THROUGH
LATE TUESDAY AFTERNOON AND EVENING. ARCTIC AIR WILL REMAIN OVER
THE REGION THROUGH THURSDAY WITH MUCH BELOW NORMAL TEMPERATURES.
THE MODELS ALL SHOW A CLIPPER SYSTEM DROPPING SOUTHEAST ALONG THE
ARCTIC BOUNDARY LATE TUESDAY NIGHT THROUGH WEDNESDAY NIGHT. AT
THIS TIME THEY ALL SHOW SOME SNOW WITH THIS SYSTEM MAINLY ACROSS
THE WESTERN CWA. THUS...INCREASED POPS SOME AND MAY HAVE TO
INCREASE THEM MORE IN LATER FORECASTS.
&&
.AVIATION...
12Z TAFS FOR THE KABR...KATY...KPIR AND KMBG TERMINALS
MVFR/LOW VFR STRATUS CLOUDS ARE EXPECTED OVER ALL TAF LOCATIONS
THROUGH THE DAY AS LOW LEVEL RH REMAINS HIGH IN THE MIXING LAYER.
AS NORTHWEST WINDS COME AROUND TO THE NORTH AND NORTHEAST TONIGHT
...EXPECT CEILINGS TO FALL TO LOW MVFR/IFR AT ALL LOCATIONS REMAINING
THROUGH THE REST OF THE PERIOD. WILL ALSO HAVE TO WATCH FOR SOME
LIGHT SNOW SHOWERS MAINLY FOR TONIGHT.
&&
.ABR WATCHES/WARNINGS/ADVISORIES...
SD...NONE.
MN...NONE.
&&
$$
UPDATE...MOHR
SHORT TERM...SD
LONG TERM...MOHR
AVIATION...MOHR
WEATHER.GOV/ABERDEEN
AREA FORECAST DISCUSSION
NWS SIOUX FALLS SD
408 AM CST FRI FEB 20 2015
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 408 AM CST FRI FEB 20 2015
SNOWFALL WHICH HAS BEEN SCARCE SO FAR OVERNIGHT WILL GET ONE LAST
CHANCE THROUGH THE REMAINDER OF THE OVERNIGHT AS UPPER WAVE SHEARS
SOUTHEAST FROM NORTHEAST SOUTH DAKOTA INTO SOUTHERN MINNESOTA. WHILE
MARKEDLY BETTER CHANCE JUST NORTHEAST OF THE CWA...HAVE INCLUDED
SMALLER CHANCE POPS FOR THE REST OF THE OVERNIGHT TO COVER TIMING OF
WAVE. FOLLOWING THIS WAVE...OTHER THAN THE INCREASINGLY SHALLOW
LOWER LEVEL WARM ADVECTION...PRETTY MUCH SET UP FOR A PERIOD OF
FAIRLY LACKLUSTER FORCING BEHIND THIS WAVE THROUGH THE AFTERNOON...
WITH THE EVENTUAL NORTH-SOUTH SPLIT TO UPSTREAM SYSTEM PUSHING A
FRONTAL BOUNDARY INTO THE NORTHERN CWA DURING THE LATER AFTERNOON.
SEVERAL MODELS INDICATE THAT THERE WILL BE SOME LIGHT QPF NEAR THIS
BOUNDARY DURING THE LATER AFTERNOON...BUT MUCH OF THIS LOOKS TO BE A
RESULT OF SURFACE BASED DESTABILIZATION RATHER THAN ANY DYNAMICAL
LIFT FORCING WHICH REMAINS MINIMAL THROUGH THE DAY.
IT WILL BE SIGNIFICANTLY WARMER TODAY ACROSS THE AREA...WITH THE
GREATEST CHALLENGE TO THIS WARMING TO BE THE EXTENT OF CLOUDINESS
GIVEN A RELATIVE LACK OF SNOW COVER. BEHIND THE EARLY MORNING UPPER
WAVE...EXPECT MORE WIDESPREAD LOWER CLOUDINESS ACROSS CENTRAL NORTH
DAKOTA TO CONTINUE TO SURGE SOUTHEASTWARD...AS IS CURRENTLY UNDERWAY
IN NORTH CENTRAL SD. RAP SEEMS TO HAVE AN ADEQUATE HANDLE ON THE
SHORT TERM BEHAVIOR OF THE CLOUD FIELDS...AND HAVE GENERALLY USED AS
A GUIDE TO TRANSLATE THE LOWER CLOUDS SOUTH AND EAST THROUGH THE
DAY...HOLDING TOUGH MUCH OF THE DAY ACROSS SW MN AND INTO PARTS OF
NW IA. GIVEN TEMPS IN THE UPPER 20S TO AROUND 30 UNDER THE INCREASED
CLOUDS...AM HESITANT TO GO QUITE AS COOL AS SEVERAL SOLUTIONS
SUGGEST...AND HAVE BASED OFF A MODIFIED RAP SURFACE THERMAL FIELD
THROUGH THE DAY. THERE WILL AT LEAST BE A FAIR AMOUNT OF HIGHER
CLOUDS AROUND IN OTHER AREAS SOUTHWEST OF THE LOWER CLOUDS...WHERE
WHICH IT WILL LIKELY PUSH 50 DEGREES ON MIXING ALONE IN THE WESTERN
MISSOURI VALLEY...AND EVEN A MODEST RIDE INTO THE LOWER 30S EXPECTED
IN SW MN.
LOWER LEVEL COLD AIR WILL BEGIN TO SURGE SOUTHWARD...ESPECIALLY
THROUGH THE LATTER HALF OF THE NIGHT...WITH FAIRLY STRONG
ISALLOBARIC RISES SET TO DRIVE AN INCREASING NORTHERLY WIND THROUGH
THE NIGHT. THIS TYPE OF SET UP ALMOST ALWAYS HAS THE COOLING COMING
IN A MORE FORCEFUL WAY...AND HAVE PUSHED THE COOLING RATES UP ABOUT
3 HOURS LATER TONIGHT AND EARLY SATURDAY MORNING THAN EVEN SOME OF
THE COOLER RAW GUIDANCE. GRADUALLY...THERMAL FIELDS BECOME MORE
FAVORABLE FOR SHALLOW FORCED PRECIPITATION BEHIND THE FRONTAL
BOUNDARY. AT THIS TIME...HAVE PRECLUDED ANY MENTION OF MEASURABLE
SNOWFALL /OR POTENTIALLY RAINFALL EARLY EVENING IN THE WEST/...BUT
DID WORK IN A GRADUAL NORTH TO SOUTH SPREAD FOR ISOLATED TO
SCATTERED FLURRIES. WIND CHILLS BY MORNING WILL RETURN BELOW ZERO
FROM EAST CENTRAL SD THROUGH MUCH OF SW MN.
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 408 AM CST FRI FEB 20 2015
FOR THE WEEKEND...THE FORECAST CONCERN CENTERS ON THE ARCTIC AIR
MOVING IN. THE COLD AIR BEHIND THE FRONT THAT MOVES THROUGH
TONIGHT WILL CONTINUE TO SURGE SOUTHWARD ON SATURDAY. AS A RESULT
EXPECT TEMPERATURES TO BASICALLY BE STEADY OR SLOWLY FALL THROUGH
THE DAY WITH HIGHS LIKELY TO BE AROUND SUNRISE. BY EVENING
TEMPERATURES WILL RANGE FROM THE SINGLE DIGITS ABOVE ZERO NORTH OF
I90 TO THE LOWER 20S IN THE MISSOURI VALLEY. NORTHWEST WINDS WILL
BE GUSTING AS HIGH AS 30 MPH BEHIND THE FRONT AND THIS WILL
PRODUCE WIND CHILLS BELOW ZERO NORTH OF AND EAST OF THE JAMES AND
MISSOURI VALLEY THROUGHOUT THE DAY.
NORTHWEST WINDS ARE EXPECTED TO REMAIN BETWEEN 10 AND 20 MPH
SATURDAY NIGHT AND MUCH OF SUNDAY. WITH LOWS EXPECTED TO BE AT OR
BELOW ZERO IN ALL BUT THE MISSOURI VALLEY SATURDAY NIGHT...WIND
CHILLS WILL RANGE FROM -15 TO -30 LATE SATURDAY NIGHT AND SUNDAY
MORNING WITH THE COLDEST WIND CHILLS IN SOUTHWEST MINNESOTA.
DESPITE SUNSHINE AND LITTLE SNOW COVER...HIGHS SUNDAY WILL
GENERALLY BE IN THE SINGLE DIGITS ABOVE ZERO. HIGH PRESSURE WILL
MOVE FROM MINNESOTA INTO WESTERN ILLINOIS ON SOUNDAY NIGHT. WINDS
WILL DECREASE FAIRLY RAPIDLY AFTER DARK AND THEN AS THE HIGH MOVES
THROUGH IOWA...TURN TO THE SOUTH AND BEGIN TO INCREASE...ESPECIALLY
WEST OF I29. WITH CLEAR SKIES AND LIGHT WINDS...MOST LOCATIONS
WILL FALL IN THE EVENING BUT TEMPERATURES WILL BECOME STEADY OR
EVEN RISE A FEW DEGREES AFTER MIDNIGHT. AS A RESULT...LOWS WILL
BE IN THE SINGLE DIGITS BELOW ZERO EAST OF THE JAMES RIVER AND IN
THE SINGLE DIGITS ABOVE ZERO WEST OF THE JAMES RIVER.
IN THE EXTENDED...MONDAY THROUGH THURSDAY...IT WILL BE A CONTRAST
IN REGIMES...WITH NEAR NORMAL TO ABOVE NORMAL TEMPERATURES MONDAY
AND TUESDAY AND BELOW NORMAL TEMPERATURES WEDNESDAY AND THURSDAY
AS ANOTHER SURGE OF ARCTIC AIR MOVES INTO THE AREA. THERE IS
SURPRISINGLY LITTLE DIFFERENCE IN THE OVERALL PATTERN BETWEEN THE
ECMWF...GFS AND THE GFS ENSEMBLE. SO CONFIDENCE IS HIGH IN TERMS
OF THE TEMPERATURE TRENDS. THE ONLY UNCERTAINTY RESTS WITH THE
CHANCE OF SNOW ON WEDNESDAY AND WEDNESDAY NIGHT. THE ECMWF IS
WEAKER WITH THE SNOWFALL...BASICALLY EXTENDING FROM WESTERN NORTH
DAKOTA...THROUGH MUCH OF SOUTH DAKOTA...AND INTO EASTERN NEBRASKA
AND FAR WESTERN IOWA. THE GFS IS GENERALLY IN THE SAME AREA BUT
FASTER AND WITH MORE SNOWFALL. WITH AN ARCTIC AIR MASS IN
PLACES...MOISTURE WILL BE LIMITED SO A SOLUTION CLOSER TO THE
ECMWF SEEMS MORE LIKELY AT THIS POINT.
ON MONDAY WILL SEE A GRADUAL WARMING AS WINDS INCREASE OUT OF THE
SOUTHWEST. BY AFTERNOON IT COULD BECOME QUITE BREEZY AND WITH
SKIES EXPECTED TO BE PARTLY TO MOSTLY SUNNY...THE ATMOSPHERE
SHOULD BECOME MORE MIXED THROUGH THE DAY. AS A RESULT...EXPECT TO
SEE QUITE A DIURNAL RANGE WITH HIGHS WARMING 25 TO 30 DEGREES INTO
THE MID 20S TO MID 30S. WITH WEST TO NORTHWEST FLOW CONTINUING
MONDAY NIGHT...EXPECT TEMPERATURES TO REMAIN IN THE 20S. TUESDAY
WILL SEE THE PASSAGE OF THE NEXT ARCTIC FRONT. WITH STRONG
NORTHWEST WINDS BEHIND THE FRONT...EXPECT THE AIR ALOFT TO MIX TO
THE SURFACE HELPING TEMPERATURES TO RISE BACK ABOVE FREEZING
BEFORE THE REAL COLD AIR MOVES BACK IN TUESDAY NIGHT. HIGHS
WEDNESDAY WILL BE IN THE TEENS AND 20S WITH EVEN COLDER
TEMPERATURES EXPECTED THURSDAY. WITH THE COLD AIR IN CANADA WOULD
NOT BE SURPRISED IF THIS AIR MASS ENDS UP A FEW DEGREES COLDER
THAN FORECAST BUT WILL WAIT UNTIL THERE IS MORE CONFIDENCE IN THE
MAGNITUDE OF THE COLD AIR BEFORE LOWERING TEMPERATURES EVEN MORE.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z FRIDAY EVENING)
ISSUED AT 1040 PM CST THU FEB 19 2015
MAINLY EXPECTING VFR CONDITIONS THROUGH THE NIGHT AT TAF SITES.
LIGHT SNOW AND FLURRIES STILL HAVING A TOUGH TIME REACHING THE
GROUND...BUT STILL MAY GET A BRIEF PERIOD OF MVFR VIS EAST OF
INTERSTATE 29 IN LIGHT SNOW. OTHERWISE SIGNS THAT LOWER MVFR STRATUS
CURRENTLY OVER NORTH DAKOTA AND CANADA WILL TRY TO WORK SOUTH BEHIND
THE COLD FRONT AFTER 12Z FRIDAY. STILL QUITE A BIT OF UNCERTAINTY ON
HEIGHT AND COVERAGE OF THIS STRATUS...BUT ENOUGH CONFIDENCE THAT
DECIDED TO INTRODUCE A PERIOD OF MVFR CIGS AT KHON AND KFSD FRIDAY
MORNING. EXPECT THIS SHOULD INCREASE BACK TO VFR BY AFTERNOON AT THE
TAF SITES...ALTHOUGH LOWER CIGS COULD LINGER OVER SOUTHWEST
MINNESOTA. WILL NEED TO CONTINUE TO MONITOR TRENDS IN THE
OBSERVATIONS AND FUTURE MODEL RUNS. SECONDARY COLD FRONT MOVING
THROUGH FRIDAY EVENING MAY BRING A RETURN TO THE MVFR CIGS.
&&
.FSD WATCHES/WARNINGS/ADVISORIES...
SD...NONE.
MN...NONE.
IA...NONE.
NE...NONE.
&&
$$
SHORT TERM...CHAPMAN
LONG TERM...SCHUMACHER
AVIATION...CHENARD
AREA FORECAST DISCUSSION
NWS ABERDEEN SD
345 AM CST FRI FEB 20 2015
.SHORT TERM...TODAY THROUGH SUNDAY
AS OF 9Z...A SURFACE LOW PRESSURE SYSTEM IS LOCATED OVER NORTHERN
NORTH DAKOTA. THE WARM FRONT ASSOCIATED WITH THE LOW PRESSURE IS
ALONG THE MISSOURI RIVER. THE WARM FRONT WILL PUSH EAST TODAY
ALLOWING FOR ABOVE NORMAL TEMPERATURES TO SPREAD ACROSS THE CWA.
THE PAST FEW RUNS OF THE HRRR AND RAPID REFRESH...PLUS THE NSSL
WRF ALL SUPPORT HIGHS IN THE MID 40S TO THE MID 50S FOR NORTH
CENTRAL AND CENTRAL SOUTH DAKOTA. COOLER TEMPERATURES ARE EXPECTED
IN NORTHEASTERN SOUTH DAKOTA AND WESTERN MINNESOTA.
A COLD FRONT...CURRENTLY OVER SOUTHERN CANADA...WILL SLIDE
SOUTHWARD ACROSS THE CWA LATER THIS AFTERNOON. LIGHT PRECIPITATION
IS POSSIBLE ALONG THIS FRONT...HOWEVER CHANCES APPEARS BETTER POST
FRONTAL...OR WITH THE CAA. PRECIPITATION AMOUNTS SHOULD BE RATHER
LIGHT. COLD AIR ADVECTION...THANKS TO AN ARCTIC HIGH
PRESSURE...WILL CONTINUE THROUGH SUNDAY WITH TEMPERATURES BECOMING
PROGRESSIVELY COLDER. HIGHS ON SATURDAY WILL RANGE FROM THE SINGLE
DIGITS...TO THE MID 20S. HIGHS BY SUNDAY WILL LIKELY RANGE FROM
THE SINGLE DIGITS BELOW ZERO...IN NORTHEASTERN SOUTH DAKOTA...TO
THE MID TEENS IN CENTRAL SOUTH DAKOTA.
.LONG TERM...SUNDAY NIGHT THROUGH THURSDAY
VERY GOOD AGREEMENT WITH ALL OF THE MODELS IN THE LONG TERM. THE
PERIOD BEGINS WITH ARCTIC HIGH PRESSURE CENTERED OVER EASTERN SD
BUILDING SOUTHEAST THROUGH SUNDAY NIGHT. AFTER A COLD SUNDAY
NIGHT...SOUTHWEST WINDS ON THE BACKSIDE OF THIS SURFACE HIGH WILL
BRING IN WARMER AIR WITH TEMPERATURES WARMING UP TO NEAR NORMAL BY
LATE MONDAY AFTERNOON. MONDAY NIGHT WILL BE MILD WITH PACIFIC AIR
MOVING ACROSS THE REGION ON WEST WINDS. TUESDAY WILL REMAIN NEAR
NORMAL FOR HIGHS WITH A TROUGH COMING THROUGH AS WINDS TURN
NORTHWEST AND INCREASE. AN ARCTIC BOUNDARY WILL THEN PUSH THROUGH
LATE TUESDAY AFTERNOON AND EVENING. ARCTIC AIR WILL REMAIN OVER
THE REGION THROUGH THURSDAY WITH MUCH BELOW NORMAL TEMPERATURES.
THE MODELS ALL SHOW A CLIPPER SYSTEM DROPPING SOUTHEAST ALONG THE
ARCTIC BOUNDARY LATE TUESDAY NIGHT THROUGH WEDNESDAY NIGHT. AT
THIS TIME THEY ALL SHOW SOME SNOW WITH THIS SYSTEM MAINLY ACROSS
THE WESTERN CWA. THUS...INCREASED POPS SOME AND MAY HAVE TO
INCREASE THEM MORE IN LATER FORECASTS.
&&
.AVIATION...
06Z TAFS FOR THE KABR...KATY...KPIR AND KMBG TERMINALS
VFR CONDITIONS WILL PREVAIL ACROSS THE AREA TONIGHT. WHILE RADAR
IS SHOWING RETURNS OVER SD LITTLE TO NOTHING IS MAKING IT THROUGH
THE VERY DRY LAYER FROM THE SFC UP TO 3500 FT. BEST CHANCES ARE
ACROSS WEST CENTRAL MN. MVFR CIGS WILL MOVE IN ON NORTHWEST FLOW
BEHIND THE FRONT FRIDAY MORNING/AFTERNOON.
&&
.ABR WATCHES/WARNINGS/ADVISORIES...
SD...NONE.
MN...NONE.
&&
$$
SHORT TERM...SD
LONG TERM...MOHR
AVIATION...WISE
WEATHER.GOV/ABERDEEN
AREA FORECAST DISCUSSION
NWS SIOUX FALLS SD
1040 PM CST THU FEB 19 2015
.UPDATE...
ISSUED AT 912 PM CST THU FEB 19 2015
WILL CONTINUE TO CUT BACK POPS TONIGHT...AS DRY AIR NOT BEING
OVERCOME. WILL BE HARD TO GET MUCH MORE THAN A PERIOD OF SCATTERED
FLURRIES. IF ANYONE WILL BE ABLE TO SQUEAK OUT A FEW TENTHS IT
WILL PROBABLY BE OUR FAR EASTERN COUNTIES FROM MARSHALL TO
SPENCER.
WILL BE INTERESTING TO SEE WHAT HAPPENS TOMORROW. SHOULD BE A
WARM DAY WITH WARMING TEMPERATURES ALOFT AND GOOD MIXING. HOWEVER
WILL HAVE TO WATCH THE ABUNDANCE OF STRATUS CURRENTLY SEEN OVER
NORTH DAKOTA AND SOUTHERN CANADA. THE RAP HAS A DECENT HANDLE ON
THIS AND SUGGESTS IT WILL MOVE SOUTH INTO THE NORTHEAST HALF OF
OUR CWA TOMORROW. IF THIS WERE TO HAPPEN IT WOULD LIKELY HOLD
TEMPERATURES DOWN QUITE A BIT. WILL NOT MAKE ANY CHANGES NOW...BUT
SOMETHING FOR THE OVERNIGHT SHIFT TO MORE CLOSELY EXAMINE.
&&
.SHORT TERM...(THIS EVENING THROUGH FRIDAY)
ISSUED AT 330 PM CST THU FEB 19 2015
WARM FRONT IS PRESSING EASTWARD AT THIS TIME. IN FACT CHAMBERLAIN IS
UP CLOSE TO 30 DEGREES WITH WINNER AT 34 MID THURSDAY AFTERNOON. IN
THE NEAR TERM AND FOR TONIGHT...BELIEVE THAT MANY GUIDANCE VALUES
ARE TOO COLD...IN SOME CASES WAY TOO COLD. NOT SURE WHY TEMPERATURES
WOULD PLUMMET ALL THAT MUCH WITH THIS KIND OF SOUTHERLY FLOW AND THE
WARM FRONT NOT STALLING. THEREFORE TRENDED TOWARD THE WARMER
READINGS WHICH WERE RAW ECMWF VALUES BLENDED WITH MOS CONSENSUS. NOW
ONTO THE WARM FRONTAL SNOW...WHICH HAS SO FAR BEEN TOTALLY NON
EXISTENT IN OUR WESTERN ZONES. BONE DRY AIR IN THE LOW LEVELS...
WITNESSED BY CURRENT SURFACE DEW POINT READINGS STILL HOVER NEAR
ZERO AND SINGLE DIGITS BELOW ZERO ALONG AND EAST OF THE JAMES RIVER
VALLEY...HAS NOT ALLOWED ANYTHING TO REACH THE GROUND. SOME LOW
LEVEL MOISTURE RETURN MAY INCREASE GENERALLY EAST OF I 29 THIS
EVENING AND OVERNIGHT. BUT SNOW AMOUNTS WILL BE LIGHT. WITH THE GFS
NOT SHOWING ANY MEASURABLE PRECIP FOR OUR FORECAST AREA...STILL DID
NOT GO CATEGORICAL POPS EVEN EAST OF I 29...BUT KEPT POPS IN THE
LIKELY CATEGORY FOR THOSE ZONES.
BEHIND THE WARM FRONT..FRIDAY WILL BE MILD. BLENDED THE MOS
CONSENSUS WITH THE RAW ECMWF AND GEM GLOBAL AS 925MB TEMPERATURES
CERTAINLY SUPPORT READINGS WELL INTO THE 30S AND 40S.
.LONG TERM...(FRIDAY NIGHT THROUGH THURSDAY)
ISSUED AT 330 PM CST THU FEB 19 2015
COLDER AIR WILL BEGIN FILTERING IN FRIDAY NIGHT BEHIND A BROAD AND
DIFFUSE FRONT. LOW LEVEL MOISTURE SHOULD BE FAIRLY COPIOUS WITH AND
BEHIND THE FRONT AND EXPECT A FEW FLURRIES OVER THE AREA. WILL ALSO
KEEP THAT SLIGHT CHANCE OF MEASURABLE SNOW OVER THE SOUTHWEST CORNER
FOR SATURDAY MORNING. MEANWHILE STRONG CANADIAN HIGH PRESSURE WILL
BE APPROACHING SATURDAY WITH SUBSIDENCE AND RESULTING DRYING
CLEARING OUT SKIES AND ANY FLURRIES FROM THE NORTH/NORTHEAST.
TEMPERATURES WHICH WILL COOL STEADILY BUT MODESTLY INTO THE TEENS
AND 20S FRIDAY NIGHT WILL NOT BE ABLE TO RISE MUCH SATURDAY DESPITE
THE CLEARING SKIES.
THE COLD AIR WILL CONTINUE TO FLOW IN SATURDAY NIGHT INTO SUNDAY
UNDER GENERALLY CLEAR SKIES. ANOTHER GENUINE WIND CHILL ADVISORY
EVENT SEEMS LIKELY BY SUNDAY MORNING...AT LEAST IN OUR NORTH AND
EAST. ACTUAL TEMPERATURES WILL DROP INTO THE SINGLE DIGITS BY SUNDAY
MORNING...BELOW ZERO NORTHEAST TO ABOVE ZERO SOUTHWEST. SUNDAY HIGHS
WILL WARM UNDER THE STRONG LATE FEBRUARY SUNSHINE TO THE SINGLE
DIGITS ABOVE ZERO NORTHEAST TO THE TEENS SOUTHWEST.
THE COLD HIGH WILL MOVE OVER THE AREA SUNDAY NIGHT BRINGING OF
COURSE COLD TEMPERATURES WITH LIGHT WINDS. MONDAY WILL BE A WARMING
DAY WITH AN UNFAVORABLE PATTERN AND DRY AIR COMBINING FOR NO REAL
LIGHT SNOW CHANCE. ANOTHER COLD SHOT SHOULD BEGIN TO ARRIVE TUESDAY
THOUGH THE DAY SHOULD STILL BE FAIRLY MILD...AND WILL GO WITH SOME
SMALL MENTION OF LIGHT SNOW AS PER EXTENDED GUIDANCE.
WEDNESDAY AND THURSDAY WILL SEE A PROCESSION OF UPPER WAVES WHICH
WILL STRENGTHEN/REINFORCE THE NEWEST COLD AIR PUSH...WHILE POSSIBLY
BRINGING A FEW AREAS OF LIGHT SNOW OR FLURRIES...BUT NOTHING VERY
BIG. THE MAIN QUESTION IS THE STRENGTH OF THIS PUSH WHICH HAS BEEN
CHANGING SOMEWHAT IN MODEL SOLUTIONS FROM RUN TO RUN. THE EXTENDED
GUIDANCE TAKES HIGH TEMPERATURE BACK DOWN TO TEENS AND 20S FOR
WEDNESDAY AND THURSDAY. THE 12Z GFS AND EC SUGGEST A STRONGER COLD
INVASION. WILL GO WITH THE GUIDANCE FOR NOW AND CHECK TO SEE IF THIS
SOLUTION REMAINS FOR THE NEXT COUPLE RUNS. ALSO...IF WE DONT GET
BETTER SNOW COVER IN THE NEXT FEW DAYS...SOME OF THE THE BITE WILL
REMAIN OFF THE OUTBREAK. HOWEVER...IT IS LOOKING LIKE GETTING MORE
THAN A DAY OF ABOVE OR EVEN NEAR NORMAL TEMPERATURES IS OUT OF THE
QUESTION AT LEAST UNTIL MARCH BEGINS.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z FRIDAY EVENING)
ISSUED AT 1040 PM CST THU FEB 19 2015
MAINLY EXPECTING VFR CONDITIONS THROUGH THE NIGHT AT TAF SITES.
LIGHT SNOW AND FLURRIES STILL HAVING A TOUGH TIME REACHING THE
GROUND...BUT STILL MAY GET A BRIEF PERIOD OF MVFR VIS EAST OF
INTERSTATE 29 IN LIGHT SNOW. OTHERWISE SIGNS THAT LOWER MVFR STRATUS
CURRENTLY OVER NORTH DAKOTA AND CANADA WILL TRY TO WORK SOUTH BEHIND
THE COLD FRONT AFTER 12Z FRIDAY. STILL QUITE A BIT OF UNCERTAINTY ON
HEIGHT AND COVERAGE OF THIS STRATUS...BUT ENOUGH CONFIDENCE THAT
DECIDED TO INTRODUCE A PERIOD OF MVFR CIGS AT KHON AND KFSD FRIDAY
MORNING. EXPECT THIS SHOULD INCREASE BACK TO VFR BY AFTERNOON AT THE
TAF SITES...ALTHOUGH LOWER CIGS COULD LINGER OVER SOUTHWEST
MINNESOTA. WILL NEED TO CONTINUE TO MONITOR TRENDS IN THE
OBSERVATIONS AND FUTURE MODEL RUNS. SECONDARY COLD FRONT MOVING
THROUGH FRIDAY EVENING MAY BRING A RETURN TO THE MVFR CIGS.
&&
.FSD WATCHES/WARNINGS/ADVISORIES...
SD...NONE.
MN...NONE.
IA...NONE.
NE...NONE.
&&
$$
UPDATE...CHENARD
SHORT TERM...MJ
LONG TERM...
AVIATION...CHENARD
AREA FORECAST DISCUSSION...CORRECTED
NWS CORPUS CHRISTI TX
955 PM CST SAT FEB 21 2015
.DISCUSSION...HAVE DELAYED ONSET OF TONIGHT/S STRATUS ACROSS
WESTERN 2/3 OF THE CWA BY SEVERAL HOURS. 00Z NAM AND LATEST RAP
AND HRRR INDICATE THAT A LLJ OF 20 TO 25 KTS AT 925 SHOULD
DEVELOP AFTER MIDNIGHT WITH STRATUS DEVELOPMENT RAPIDLY INCREASING
NEARLY AREAWIDE AT THAT TIME. ENOUGH MOISTURE ADVECTION WILL
LIKELY LEAD TO SOME FOG DEVELOPMENT ACROSS MARINE AREAS AND
POSSIBLY ACROSS LAND AREAS. LIGHT SHOWERS MAY ALSO DEVELOP WITHIN
LOW LEVEL FLOW ACROSS EASTERN AREAS LATE TONIGHT...WITH BETTER
CHANCES SUNDAY MORNING. ONLY OTHER CHANGE TO INHERITED FORECAST
WERE MINOR EDITS TO HOURLY DEWPOINTS. AN ADDITIONAL UPDATE MAY BE
SENT LATE THIS EVENING REGARDING RIP CURRENT RISK. FOR NOW...HAVE
HIGH RIP CURRENT ADVISORY EXPIRING AT MIDNIGHT...BUT MAY NEED TO
EXTEND THE ADVISORY THROUGH THE REMAINDER OF THE NIGHT.
&&
.PRELIMINARY POINT TEMPS/POPS...
CORPUS CHRISTI 64 76 47 51 39 / 10 20 50 60 40
VICTORIA 64 72 42 44 35 / 10 40 50 60 40
LAREDO 64 82 48 49 40 / 10 10 50 60 30
ALICE 64 81 46 50 38 / 10 20 50 60 40
ROCKPORT 63 73 47 50 40 / 10 20 50 60 40
COTULLA 60 73 43 45 38 / 10 30 50 60 30
KINGSVILLE 64 79 48 52 39 / 10 10 50 60 40
NAVY CORPUS 64 73 49 52 41 / 10 20 50 60 40
&&
.CRP WATCHES/WARNINGS/ADVISORIES...
TX...RIP CURRENT RISK UNTIL MIDNIGHT CST TONIGHT FOR THE FOLLOWING
ZONES: ARANSAS...CALHOUN...KLEBERG...NUECES.
GM...SMALL CRAFT ADVISORY UNTIL 6 AM CST SUNDAY FOR THE FOLLOWING
ZONES: WATERS FROM BAFFIN BAY TO PORT ARANSAS FROM 20 TO 60
NM...WATERS FROM PORT ARANSAS TO MATAGORDA SHIP CHANNEL
FROM 20 TO 60 NM.
SMALL CRAFT ADVISORY UNTIL 11 PM CST THIS EVENING FOR THE
FOLLOWING ZONES: COASTAL WATERS FROM BAFFIN BAY TO PORT
ARANSAS OUT 20 NM...COASTAL WATERS FROM PORT ARANSAS TO
MATAGORDA SHIP CHANNEL OUT 20 NM.
&&
$$
UPDATE...HART/79
AREA FORECAST DISCUSSION...UPDATED
NWS CORPUS CHRISTI TX
946 PM CST SAT FEB 21 2015
.DISCUSSION...HAVE DELAYED ONSET OF TONIGHT/S STRATUS ACROSS
WESTERN 2/3 OF THE CWA BY SEVERAL HOURS. 00Z NAM AND LATEST RAP
AND HRRR INDICATE THAT A LLJ OF 20 TO 25 KTS AT 925 SHOULD AFTER
MIDNIGHT WITH STRATUS DEVELOPMENT RAPIDLY INCREASING NEARLY
AREAWIDE AT THAT TIME. ENOUGH MOISTURE ADVECTION WILL LIKELY LEAD
TO SOME FOG DEVELOPMENT ACROSS MARINE AREAS AND POSSIBLY ACROSS
LAND AREAS. LIGHT SHOWERS MAY ALSO DEVELOP WITHIN LOW LEVEL FLOW
ACROSS EASTERN AREAS LATE TONIGHT...WITH BETTER CHANCES SUNDAY
MORNING. ONLY OTHER CHANGE TO INHERITED FORECAST WERE MINOR EDITS
TO HOURLY DEWPOINTS. AN ADDITIONAL UPDATE MAY BE SENT LATE THIS
EVENING REGARDING RIP CURRENT RISK. FOR NOW...HAVE HIGH RIP
CURRENT ADVISORY EXPIRING AT MIDNIGHT...BUT MAY NEED TO EXTEND THE
ADVISORY THROUGH THE REMAINDER OF THE NIGHT.
&&
.PRELIMINARY POINT TEMPS/POPS...
CORPUS CHRISTI 64 76 47 51 39 / 10 20 50 60 40
VICTORIA 64 72 42 44 35 / 10 40 50 60 40
LAREDO 64 82 48 49 40 / 10 10 50 60 30
ALICE 64 81 46 50 38 / 10 20 50 60 40
ROCKPORT 63 73 47 50 40 / 10 20 50 60 40
COTULLA 60 73 43 45 38 / 10 30 50 60 30
KINGSVILLE 64 79 48 52 39 / 10 10 50 60 40
NAVY CORPUS 64 73 49 52 41 / 10 20 50 60 40
&&
.CRP WATCHES/WARNINGS/ADVISORIES...
TX...RIP CURRENT RISK UNTIL MIDNIGHT CST TONIGHT FOR THE FOLLOWING
ZONES: ARANSAS...CALHOUN...KLEBERG...NUECES.
GM...SMALL CRAFT ADVISORY UNTIL 6 AM CST SUNDAY FOR THE FOLLOWING
ZONES: WATERS FROM BAFFIN BAY TO PORT ARANSAS FROM 20 TO 60
NM...WATERS FROM PORT ARANSAS TO MATAGORDA SHIP CHANNEL
FROM 20 TO 60 NM.
SMALL CRAFT ADVISORY UNTIL 11 PM CST THIS EVENING FOR THE
FOLLOWING ZONES: COASTAL WATERS FROM BAFFIN BAY TO PORT
ARANSAS OUT 20 NM...COASTAL WATERS FROM PORT ARANSAS TO
MATAGORDA SHIP CHANNEL OUT 20 NM.
&&
$$
UPDATE...HART/79
FOR FREQUENTLY ASKED QUESTIONS ABOUT THE AREA FORECAST DISCUSSION
VISIT...
HTTP://WEATHER.GOV/SALTLAKECITY/GENERAL/AFD_FAQS.PHP (ALL LOWER CASE)
AREA FORECAST DISCUSSION
NWS GREEN BAY WI
534 PM CST SAT FEB 21 2015
UPDATED AVIATION PORTION FOR 00Z TAF ISSUANCE
.SHORT TERM...TONIGHT AND SUNDAY
ISSUED AT 224 PM CST SAT FEB 21 2015
THE LATEST RAP ANALYSIS AND SATELLITE/RADAR IMAGERY SHOW THE NEXT
ARCTIC COLD FRONT DROPPING SOUTHEAST ACROSS NORTH-CENTRAL TO
WEST-CENTRAL WISCONSIN EARLY THIS AFTERNOON. LIGHT AREA OF SNOW
RESIDING WITHIN A WEAK MID-LEVEL FGEN ZONE IS MOVING EAST ACROSS
CENTRAL WISCONSIN...THOUGH SUSPECT SOME OF THAT AREA IS NOT REACHING
THE GROUND. ADDITIONALLY...ALSO SEEING LIGHT RETURNS DEVELOPING
OVER OCONTO AND MARINETTE COUNTIES WHERE WEAK SURFACE CONVERGENCE
HAS DEVELOPED. THIS WILL LIKELY EXPAND LATER THIS AFTERNOON BASED ON
TRENDS AND ACCORDING TO THE HI-RES MODELS. BEHIND THE
FRONT...ARCTIC HIGH PRESSURE IS BUILDING SOUTHEAST INTO THE NORTHERN
PLAINS WHERE TEMPS WERE WELL BELOW ZERO EARLIER THIS MORNING.
FORECAST CONCERNS INCLUDE LIGHT SNOW CHANCES THROUGH THIS
EVENING...BEFORE ATTENTION TURNS TO DANGEROUS WIND CHILLS.
TONIGHT...A SHORTWAVE TROUGH OVER SOUTH-CENTRAL CANADA WILL DRIVE
THE COLD FRONT ACROSS THE REST OF THE REGION THIS EVENING...WHILE A
BEEFY ARCTIC HIGH MOVES INTO THE NORTHERN GREAT PLAINS AND WESTERN
GREAT LAKES. AHEAD OF THE SHORTWAVE...THE HIGHER RES MODELS ARE
DEPICTING A WEAK SURFACE TROUGH DEVELOPING OVER NORTHEAST WISCONSIN
THIS EVENING WHICH COULD PROMOTE LIGHT SNOW DEVELOPMENT. HAVE KEPT
A SMALL CHANCE IN THE FORECAST THROUGH THE EVENING TO ACCOUNT FOR
THIS FEATURE. OTHERWISE...THE INCOMING ARCTIC HIGH WILL PUSH
RESIDUAL MID-LEVEL MOISTURE TO THE EAST WHICH WILL END SNOW CHANCES
BY AROUND MIDNIGHT. TEMPERATURES SHOULD FALL QUICKLY AS SKIES CLEAR
AND ARCTIC AIR POURS ACROSS THE REGION. POTENTIAL IS THERE FOR
DECOUPLING OVER N-C WISCONSIN...BUT THINKING IF WINDS BECOME CALM IT
WILL BE ONLY FOR A BRIEF TIME. THE COMBINATION OF COLD TEMPS AND
THE BRISK NW WINDS SUPPORT THE WIND CHILL ADVISORY CURRENTLY IN
EFFECT SO NO CHANGES TO HEADLINES.
SUNDAY...COLD ADVECTION WILL CONTINUE INTO SUNDAY MORNING AND TEMPS
COULD CONTINUE THEIR FALL INTO MID-MORNING DESPITE AMPLE SUNSHINE.
THE PRESSURE GRADIENT WILL SLACKEN A BIT THROUGH THE DAY AS THE
CENTER OF THE HIGH DRIFTS CLOSER TO THE REGION...BUT PROJECTED WIND
CHILLS WILL ONLY WARM TO AROUND 15 TO 22 BELOW THROUGH THE
AFTERNOON. THIS IS CLOSE ENOUGH TO LEAVE THE ENDING TIME OF THE
ADVISORY ALONE. HIGHS WILL ONLY WARM INTO THE -5 TO 0 RANGE NORTH
TO THE 5 TO 10 ABOVE RANGE SOUTH.
.LONG TERM...SUNDAY NIGHT THROUGH SATURDAY
ISSUED AT 224 PM CST SAT FEB 21 2015
A LOOK AT THE RECENT BEHAVIOR OF THE 500 MB PATTERN FITS IN WELL
WITH OUR TEMPERATURES THIS MONTH. A WESTERN RIDGE AND EASTERN
TROUGH ARE QUITE PERSISTENT...SHOWING CHANGES MORE IN AMPLITUDE
THAN POSITION. WITH THAT...OUR TEMPERATURES HAVE SPENT TIME
VARYING BETWEEN BELOW NORMAL AND WAY BELOW NORMAL. FOR THE TIME
BEING...THIS TREND LOOKS TO CONTINUE.
SUNDAY NIGHT INTO MONDAY MORNING SHOWS TEMPERATURES BOTTOMING OUT
NEARLY AS LOW AS THEY HAVE GOTTEN THIS WINTER. FORECASTING WIND
CHILLS WILL BE DIFFICULT ACROSS THE NORTH. CALM WINDS WILL HELP
TEMPERATURES FALL TO THEIR COLDEST POSSIBLE LEVELS...BUT CALM
CONDITIONS COULD PRECLUDE A WARNING BY NOT MEETING THE WIND
THRESHOLD. MORE WIND WILL HELP PUSH WIND CHILLS DOWN...BUT WOULD
BE LIMITING BY ARRESTING TEMPERATURE FALLS. GIVEN THE
UNCERTAINTY...WILL LET LATER SHIFTS MAKE THE FINAL DECISION ON
ANYTHING TO BE ISSUED FOR WIND CHILL. AN ADVISORY FOR MOST OR ALL
OF THE AREA IS PLAUSIBLE...AND A WARNING IN NORTH CENTRAL
WISCONSIN MAY BE ON THE TABLE. THOUGH THERE MIGHT BE A LACK OF
CONFIDENCE IN THE PRECISE HEADLINES...CONFIDENCE IS QUITE HIGH
THAT IT WILL BE VERY COLD AND THOSE GOING TO WORK AND SCHOOL
MONDAY MORNING SHOULD PREPARE ACCORDINGLY.
INCREASING SOUTHWEST WINDS ON MONDAY CAN BE EXPECTED...ESPECIALLY
LATE IN THE AFTERNOON AND EVENING HOURS. THESE WINDS WILL HELP
BOOST TEMPERATURES LATE MONDAY INTO TUESDAY. WITH ANOTHER IN THE
PARADE OF LOWS SLIDING BY TO OUR NORTHEAST BRINGING AN ARCTIC
FRONT TO OUR AREA...WE WILL HAVE ANOTHER CHANCE FOR SNOW SHOWERS.
GUIDANCE REMAINS FRUSTRATINGLY ON THE EDGE BETWEEN BRINGING SOME
LIGHT SNOW WELL INTO THE AREA...OR ONLY BRINGING A GLANCING BLOW
TO THE NORTH AND EAST. ULTIMATELY THIS FORECAST DOES NOT MAKE
SIGNIFICANT CHANGES...THE EQUIVALENT OF DUMPING THE PUCK INTO THE
CORNER AND HOPING THAT A LINE CHANGE OF MODELS WILL BRING MORE
CLARITY.
BITTER COLD RETURNS FOR WEDNESDAY AND THURSDAY BUT WITH SOME HOPE FOR
A SLIGHT BUMP UP TO MERELY BELOW NORMAL TEMPERATURES LATE IN THE WEEK.
&&
.AVIATION...FOR 00Z TAF ISSUANCE
ISSUED AT 533 PM CST SAT FEB 21 2015
STEEP LOW-LEVEL LAPSE RATES WL CONT TO PRODUCE LIGHT SNOW SHOWERS
OR FLURRIES ACROSS E-CNTRL WI EARLY THIS EVENING. MVFR CIGS/VSBYS
WOULD ACCOMPANY THIS PCPN ACROSS THE GRB...ATW AND MTW TAF SITES
THRU AROUND 02Z BEFORE IMPROVING CONDITIONS ARE NOTED. OTHERWISE...
LOW-END VFR CIGS OVER THE REST OF NE WI WL GRADUALLY DISSIPATE AS
HI PRES TO BUILD TOWARD THE WRN GREAT LAKES TNGT. LOOK FOR SKIES
TO GRADUALLY CLEAR FROM NW TO SE DURING THE NGT...THUS VFR
CONDITIONS TO PREVAIL. SUNDAY SHOULD BE A NICE FLYING DAY WITH
ONLY A SCT CU FIELD DEVELOPING. NW WINDS WL BE ON THE INCREASE BY
SUNDAY AFTERNOON WITH A FEW GUSTS APPROACHING 25 KTS.
&&
.GRB WATCHES/WARNINGS/ADVISORIES...
WIND CHILL ADVISORY FROM 3 AM TO 11 AM CST SUNDAY FOR WIZ005-
010>012-018-019-030-035-036.
&&
$$
SHORT TERM.....MPC
LONG TERM......LUCHS
AVIATION.......AK
AREA FORECAST DISCUSSION
NWS MOUNT HOLLY NJ
503 AM EST SUN FEB 22 2015
.SYNOPSIS...
AN AREA OF LOW PRESSURE WILL MOVE THROUGH NORTHERN NEW ENGLAND
AND INTO SOUTHEASTERN CANADA THROUGH TODAY, DRAGGING A FRONTAL
SYSTEM ACROSS THE REGION. HIGH PRESSURE WILL BUILD OUT OF THE
CENTRAL PART OF THE COUNTRY ON MONDAY AND INTO OUR AREA MONDAY
NIGHT INTO TUESDAY. AN AREA OF LOW PRESSURE IS FORECAST TO MOVE
ALONG THE SOUTHERN TIER OF CANADA TUESDAY INTO WEDNESDAY, PULLING
A COLD FRONT ACROSS THE EAST COAST ON WEDNESDAY. HIGH PRESSURE IS
EXPECTED TO RETURN AGAIN LATE THURSDAY INTO FRIDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
SOME LEFTOVER ONGOING PRECIP EARLY TODAY AS LOW PRESSURE PROGRESSES
NORTHEASTWARD, WITH ITS ASSOCIATED FRONTS CROSSING OUR REGION.
WINTER WEATHER ADVISORY AND WARNING HEADLINE PRODUCTS WILL CONTINUE
THROUGH EARLY MORNING, AS SOME LIGHT FROZEN PRECIP CONTINUES,
ESPECIALLY ACROSS PORTIONS OF EASTERN PA AND INTO NORTHERN NJ. WHILE
MAINLY LIGHT SNOW CONTINUES THROUGH NORTHERN NJ, THE POCONOS, AND
INTO THE LEHIGH VALLEY, PRECIPITATION IS PRIMARILY FALLING AS
FREEZING RAIN FARTHER SOUTH INTO THE REMAINDER OF SOUTHEASTERN PA,
INCLUDING THE WESTERN PHL METRO SUBURBS, WHERE A WARM LAYER EXISTS
ABOVE THE SUB-FREEZING SURFACE AIR. IN ADDITION, WE HAVE RECEIVED
REPORTS OF SOME ICING INTO SOUTHERN PARTS OF NJ, WHERE PRECIPITATION
IS FALLING PRIMARILY AS RAIN, BUT THE GROUND REMAINS FROZEN.
WE THEREFORE HAVE DECIDED TO RAISE A FREEZING RAIN ADVISORY THROUGH
14Z FOR PORTIONS OF SOUTHERN NJ AND INTO THE CENTRAL DELMARVA WHERE
SURFACE AIR TEMPERATURES REMAIN CLOSE TO FREEZING AND LIGHT PRECIP
IS FALLING. THE STILL FROZEN GROUND WILL LIKELY YIELD SOME LIGHT
ICING ACROSS THESE AREAS AS LIGHT RAIN CONTINUES FOR A FEW MORE
HOURS. IN ADDITION, WE HAVE EXTENDED PORTIONS OF THE WINTER STORM
WARNING THROUGH 14Z ACROSS NORTHERN DELAWARE, THE PHL METRO AREA,
AND CENTRAL NEW JERSEY AS SOME LIGHT RAIN WILL CONTINUE TO FALL OVER
STILL FROZEN GROUND.
BY MID TO LATE MORNING, IMPROVEMENT IS ANTICIPATED FOR THE ENTIRE
FORECAST AREA, AS THE HRRR SHOWS ANY REMAINING LIGHT PRECIP MOVING
EAST AND OFFSHORE, WITH TEMPERATURES INTO AT LEAST THE MID 30S FOR
MOST LOCATIONS. SOME CLOUDINESS WILL LINGER INTO THE AFTERNOON, AND
WITH THIS IN MIND, AS WELL AS CONSIDERING THE REMAINING SNOWPACK
ACROSS THE REGION, WE UNDERCUT MET/MAV GUIDANCE BY A COUPLE OF
DEGREES ACROSS THE FORECAST AREA WITH REGARD TO MAXIMUM
TEMPERATURES. WE ANTICIPATE HIGHS TO MAINLY BE IN THE MIDDLE TO
UPPER 30S FOR THE FORECAST AREA, EXCEPT SOME LOWER 40S ACROSS
SOUTHERN NJ AND INTO THE DELMARVA, WITH COLDER UPPER 20S/LOWER 30S
REMAINING INTO THE POCONOS.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 AM MONDAY/...
AS THE PREVIOUSLY MENTIONED LOW PRESSURE SYSTEM EXITS FARTHER
OFFSHORE THROUGH TONIGHT, A NEW PUSH OF COLDER, DRIER AIR WILL BE
FELT ACROSS THE REGION ON NORTHWEST BREEZES IN THE WAKE OF THE
DEPARTING LOW PRESSURE AND COLD FRONT. IN ADDITION, A MID-LEVEL
TROUGH WILL BE SETTLING ACROSS THE NORTHEAST TO MID ATLANTIC STATES
AS ARCTIC HIGH PRESSURE GRADUALLY BUILDS EAST FROM THE PLAINS AND
MIDWEST. OVERALL, DRY CONDITIONS ARE EXPECTED THROUGH THE NIGHTTIME
HOURS, SAVE PERHAPS A FEW ISOLATED/SCATTERED SNOW SHOWERS IN THE
POCONOS ON THE NORTHWEST FLOW. WE MOSTLY TOOK A MET/MAV GUIDANCE
BLEND WITH CONTINUITY FOR MINIMUM TEMPS, AND WE EXPECT SOME SINGLE
DIGIT LOW TEMPERATURES IN THE FAR NORTHWEST TO MAINLY TEENS AND
LOWER 20S ELSEWHERE.
&&
.LONG TERM /MONDAY THROUGH SATURDAY/...
UPDATED DISCUSSION TO FOLLOW.
MONDAY WILL BE ANOTHER COLD AND BREEZY DAY. WITH LOW THICKNESSES
AND 925 MB TEMPERATURES, TEMPERATURES WILL RANGE FROM THE 20S
ACROSS THE SOUTHERN HALF, TO THE TEENS ACROSS THE NORTHERN HALF,
AND SINGLE DIGITS FAR NORTH. THIS WILL CREATE LOW WIND CHILLS
THROUGH THE DAY, IN THE SINGLE DIGITS FOR MUCH OF THE AREA, TO
BELOW ZERO FOR THE COLDEST. THE COLD TEMPERATURES WILL CONTINUE
INTO MONDAY NIGHT, WITH MOST PLACES IN THE SINGLE DIGITS, TO MINUS
SINGLE DIGITS IN SOME AREAS. ALTHOUGH HIGH PRESSURE BUILDS ACROSS
THE AREA, THERE WILL BE SOME WIND THAT WILL KEEP THE LOW WIND
CHILLS IN THE SINGLE DIGITS FOR MUCH OF THE AREA, TO BELOW ZERO
FOR THE COLDEST.
ON TUESDAY, THE HIGH PRESSURE BUILDS OFFSHORE WHICH WILL SWITCH
WINDS TO A MORE SOUTHERLY DIRECTION, HELP MODERATING TEMPERATURES
A FEW DEGREES. HOWEVER, IT WILL STILL BE WELL BELOW NORMAL. NO
PRECIPITATION IS EXPECTED AS THE AIR REMAINS DRY STILL, ALTHOUGH
THERE IS A SLIGHT INCREASE AHEAD OF AN APPROACHING FRONTAL
BOUNDARY.
A COLD FRONT IS FORECAST TO MOVE ACROSS THE AREA LATE TUESDAY
NIGHT INTO WEDNESDAY MORNING. THE GFS HAS SOME LIGHT QPF MOVING
ACROSS THE AREA, WHILE THE ECMWF DOES NOT. THERE IS NOT A LOT OF
MOISTURE OR ASSOCIATED LIFT FORECAST EITHER WAY, SO WE WILL ONLY
KEEP A SMALL CHANCE OF SNOW OVERNIGHT INTO WEDNESDAY, MAINLY FOR
THE NORTHERN HALF OF THE AREA.
ON WEDNESDAY NIGHT INTO THURSDAY, AN AREA OF LOW PRESSURE IS
FORECAST TO DEVELOP ALONG THE AFOREMENTIONED FRONTAL BOUNDARY TO
OUR SOUTH. ANY ASSOCIATED PRECIPITATION IS EXPECTED TO REMAIN
MOSTLY TO OUR SOUTH, BUT THERE IS A SLIGHT CHANCE THAT SOME SNOW
MAY MAKE ITS WAY INTO OUR FAR SOUTHERN AND SOUTHEASTERN AREAS. SO
WE WILL KEEP A SLIGHT CHANCE OF SNOW.
COLD TEMPERATURES RETURN BEHIND THIS FRONTAL BOUNDARY FOR THE END
OF THE WEEK. ESPECIALLY AS HIGH PRESSURE MOVES INTO THE AREA
THURSDAY NIGHT INTO FRIDAY. LOWS THURSDAY NIGHT WILL LIKELY GET
INTO THE SINGLE DIGITS TO BELOW ZERO AGAIN. ANOTHER PERIOD OF
SINGLE DIGIT TO BELOW ZERO WIND CHILLS IS EXPECTED WEDNESDAY NIGHT
THROUGH FRIDAY MORNING.
&&
.AVIATION /10Z SUNDAY THROUGH THURSDAY/...
THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG,
KILG, KMIV, KACY AND SURROUNDING AREAS.
EARLY MORNING...IFR CONDITIONS ARE IN PLACE ACROSS THE REGION AND
ARE EXPECTED TO LAST THROUGH THE EARLY MORNING HOURS. ALL SITES
FROM THE COAST TO THE DELAWARE VALLEY REGION HAVE TRANSITIONED
OVER TO RAIN, EXCEPT KABE AND KRDG WHERE LIGHT SNOW OR SOME
FREEZING RAIN IS EXPECTED BEFORE THE PRECIPITATION ENDS AROUND
DAYBREAK. IN FACT, PRECIPITATION IS FORECAST TO END FROM WEST TO
EAST ACROSS THE REGION BETWEEN ABOUT 1000Z AND 1300Z. WINDS ARE
EXPECTED TO REMAIN LIGHT, MAINLY OUT OF THE SOUTHWEST, OR PERHAPS
GO LIGHT AND VARIABLE FOR A TIME.
REST OF SUNDAY...WHILE PRECIPITATION ENDS EARLY, THE LOWER
CIGS/VSBYS, MAINLY IN THE IFR RANGE, ARE EXPECTED TO REMAIN
THROUGH AT LEAST THE MORNING. WHEN EXACTLY THE LOWER CONDITIONS
WILL BREAK WITH A RETURN TO VFR IS A TRICKY FORECAST AT THIS TIME,
AND THERE ARE DIFFERENCES IN THE GUIDANCE WITH RESPECT TO THIS
OCCURRENCE. FOR NOW, WE HAVE KEPT AN IMPROVEMENT TO VFR BETWEEN
AROUND 16Z TO 18Z, BUT THIS IS A LOW CONFIDENCE FORECAST AS THE
NOTICEABLE PUSH OF COLD, DRY AIR INTO THE REGION DOES NOT OCCUR
UNTIL SUNDAY EVENING/NIGHT. WINDS THROUGH THE DAYTIME SUNDAY ARE
EXPECTED TO BECOME MORE WESTERLY AND THEN NORTHWESTERLY, REMAINING
MOSTLY IN THE 4 TO 8 KNOT RANGE.
OUTLOOK...
SUNDAY NIGHT AND MONDAY...VFR EXPECTED. GUSTY NORTHWEST WINDS
20-25 KNOTS.
MONDAY NIGHT AND TUESDAY...VFR EXPECTED.
TUESDAY NIGHT AND WEDNESDAY...SLIGHT CHANCE OF SNOW SHOWERS.
LOWER CIGS/VSBYS POSSIBLE WITH ANY SHOWERS, OTHERWISE, MOSTLY VFR
EXPECTED. GUSTY NORTHWEST WINDS 20-25 KNOTS DURING THE DAY.
WEDNESDAY NIGHT-THURSDAY...VFR EXPECTED.
&&
.MARINE...
**SINCE MUCH OF DELAWARE BAY IS COVERED BY ICE WE WILL CONTINUE
TO ADD THE PHRASING "ON ICE FREE WATERS" FOR THE FIRST FOUR
PERIODS OF THE FORECAST**
WHILE LIGHTER WINDS BELOW 20 KNOTS ARE EXPECTED FOR OUR AREA WATERS
THROUGH TODAY, SEAS ON THE COASTAL WATERS SHOULD REMAIN AROUND 5
FEET OR SO, ESPECIALLY FOR THE OUTER WATERS AWAY FROM THE NEAR
SHORE. WE THEREFORE CONTINUE THE SMALL CRAFT ADVISORY FOR OUR
COASTAL WATERS THROUGH TODAY, ALTHOUGH CONDITIONS COULD BRIEFLY FALL
BELOW CRITERIA FOR A TIME. LATER TONIGHT, NORTHWESTERLY WINDS WILL
INCREASE, WITH GUSTS REACHING AROUND 25 KNOTS. SEAS MAY ALSO
INCREASE SOME IN RESPONSE. THE SCA WILL CONTINUE FOR THE COASTAL
WATERS THROUGH TONIGHT AND INTO MONDAY.
FOR THE DELAWARE BAY, BOTH SEAS AND WINDS ARE EXPECTED TO REMAIN AT
SUB-ADVISORY LEVELS THROUGH TODAY AND TONIGHT, WITH CONDITIONS THEN
MEETING SCA CRITERIA INTO MONDAY AS NORTHWESTERLY WINDS INCREASE.
OUTLOOK...
MONDAY THROUGH MONDAY NIGHT...SMALL CRAFT ADVISORY MAY NEED TO BE
EXTENDED IN FUTURE FORECASTS AS WINDS MAY REMAIN ELEVATED INTO
EARLY MONDAY NIGHT. FREEZING SPRAY LIKELY
TUESDAY THROUGH THURSDAY...WINDS AND SEAS MAY GET CLOSE TO
ADVISORY LEVELS OVERNIGHT TUESDAY NIGHT/WEDNESDAY MORNING AND
AGAIN OVERNIGHT WEDNESDAY NIGHT/THURSDAY MORNING. OTHERWISE
CONDITIONS SHOULD STAY BELOW ADVISORY LEVELS
&&
.CLIMATE...
DAILY RECORD MIN TEMPS WERE SET ON FEB 21, 2015 AT: ACY, ILG,
ABE, TTN, GED AND MPO THIS MORNING. HERE ARE THE PARTICULARS...
POR | SITE | PREV RECORD MINT (YEAR)| NEW RECORD MINT (YEAR)
1874 | KACY | 3 (1968) | -6 (2015)
1894 | KILG| 6 (1968,1934) | 3 (2015)
1922 | KABE| 0 (1936) | -3 (2015)
1865 | KTTN | 6 (1893) | 3 (2015)
1948 | KGED | 8 (1959) | -4 (2015)
1901 | KMPO | -8 (1993) | -10(2015)
NOTE: POR= PERIOD OF RECORD (YEAR THE OFFICIAL CLIMATE OBS BEGAN)
ALSO, THE -6F ON FEB 21, 2015 IS THE COLDEST TEMPERATURE RECORDED
AT ATLANTIC CITY SINCE FEBRUARY 5, 1996 AND THE LATEST OCCURRENCE
OF A SUB-ZERO TEMPERATURE IN THE SEASON ON RECORD. THE PREVIOUS
LATEST SUB-ZERO DAY IN WINTER/SPRING WAS JUST SET YESTERDAY, AND
BEFORE THAT, IT WAS FEBRUARY 18TH WHEN THE LOW WAS -7F ON THAT
DATE IN 1979.
&&
.PHI WATCHES/WARNINGS/ADVISORIES...
PA...WINTER STORM WARNING UNTIL 6 AM EST EARLY THIS MORNING FOR
PAZ060>062-101>103-105.
WINTER STORM WARNING UNTIL 9 AM EST THIS MORNING FOR PAZ070-
071-104-106.
WINTER WEATHER ADVISORY UNTIL 6 AM EST EARLY THIS MORNING FOR
PAZ054-055.
NJ...WINTER STORM WARNING UNTIL 6 AM EST EARLY THIS MORNING FOR
NJZ007>010-015.
FREEZING RAIN ADVISORY UNTIL 9 AM EST THIS MORNING FOR NJZ021-
022.
WINTER STORM WARNING UNTIL 9 AM EST THIS MORNING FOR
NJZ012>014-016>020-026-027.
WINTER WEATHER ADVISORY UNTIL 6 AM EST EARLY THIS MORNING FOR
NJZ001.
DE...FREEZING RAIN ADVISORY UNTIL 9 AM EST THIS MORNING FOR DEZ002.
WINTER STORM WARNING UNTIL 9 AM EST THIS MORNING FOR DEZ001.
MD...WINTER STORM WARNING UNTIL 6 AM EST EARLY THIS MORNING FOR
MDZ008.
FREEZING RAIN ADVISORY UNTIL 9 AM EST THIS MORNING FOR MDZ015.
WINTER STORM WARNING UNTIL 9 AM EST THIS MORNING FOR MDZ012.
MARINE...SMALL CRAFT ADVISORY UNTIL 6 PM EST MONDAY FOR ANZ450>455.
SMALL CRAFT ADVISORY FROM 6 AM TO 6 PM EST MONDAY FOR ANZ430-
431.
&&
$$
SYNOPSIS...ROBERTSON
NEAR TERM...KLINE
SHORT TERM...KLINE
LONG TERM...ROBERTSON
AVIATION...KLINE/ROBERTSON
MARINE...KLINE/ROBERTSON
CLIMATE...
AREA FORECAST DISCUSSION
NWS MOUNT HOLLY NJ
420 AM EST SUN FEB 22 2015
.SYNOPSIS...
AN AREA OF LOW PRESSURE WILL MOVE THROUGH NORTHERN NEW ENGLAND
AND INTO SOUTHEASTERN CANADA THROUGH TODAY, DRAGGING A FRONTAL
SYSTEM ACROSS THE REGION. HIGH PRESSURE WILL BUILD OUT OF THE
CENTRAL PART OF THE COUNTRY ON MONDAY AND INTO OUR AREA MONDAY
NIGHT INTO TUESDAY. AN AREA OF LOW PRESSURE IS FORECAST TO MOVE
ALONG THE SOUTHERN TIER OF CANADA TUESDAY INTO WEDNESDAY, PULLING
A COLD FRONT ACROSS THE EAST COAST ON WEDNESDAY. HIGH PRESSURE IS
EXPECTED TO RETURN AGAIN LATE THURSDAY INTO FRIDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
SOME LEFTOVER ONGOING PRECIP EARLY TODAY AS LOW PRESSURE PROGRESSES
NORTHEASTWARD, WITH ITS ASSOCIATED FRONTS CROSSING OUR REGION.
WINTER WEATHER ADVISORY AND WARNING HEADLINE PRODUCTS WILL CONTINUE
THROUGH EARLY MORNING, AS SOME LIGHT FROZEN PRECIP CONTINUES,
ESPECIALLY ACROSS PORTIONS OF EASTERN PA AND INTO NORTHERN NJ. WHILE
MAINLY LIGHT SNOW CONTINUES THROUGH NORTHERN NJ, THE POCONOS, AND
INTO THE LEHIGH VALLEY, PRECIPITATION IS PRIMARILY FALLING AS
FREEZING RAIN FARTHER SOUTH INTO THE REMAINDER OF SOUTHEASTERN PA,
INCLUDING THE WESTERN PHL METRO SUBURBS, WHERE A WARM LAYER EXISTS
ABOVE THE SUB-FREEZING SURFACE AIR. IN ADDITION, WE HAVE RECEIVED
REPORTS OF SOME ICING INTO SOUTHERN PARTS OF NJ, WHERE PRECIPITATION
IS FALLING PRIMARILY AS RAIN, BUT THE GROUND REMAINS FROZEN.
WE THEREFORE HAVE DECIDED TO RAISE A FREEZING RAIN ADVISORY THROUGH
14Z FOR PORTIONS OF SOUTHERN NJ AND INTO THE CENTRAL DELMARVA WHERE
SURFACE AIR TEMPERATURES REMAIN CLOSE TO FREEZING AND LIGHT PRECIP
IS FALLING. THE STILL FROZEN GROUND WILL LIKELY YIELD SOME LIGHT
ICING ACROSS THESE AREAS AS LIGHT RAIN CONTINUES FOR A FEW MORE
HOURS. IN ADDITION, WE HAVE EXTENDED PORTIONS OF THE WINTER STORM
WARNING THROUGH 14Z ACROSS NORTHERN DELAWARE, THE PHL METRO AREA,
AND CENTRAL NEW JERSEY AS SOME LIGHT RAIN WILL CONTINUE TO FALL OVER
STILL FROZEN GROUND.
BY MID TO LATE MORNING, IMPROVEMENT IS ANTICIPATED FOR THE ENTIRE
FORECAST AREA, AS THE HRRR SHOWS ANY REMAINING LIGHT PRECIP MOVING
EAST AND OFFSHORE, WITH TEMPERATURES INTO AT LEAST THE MID 30S FOR
MOST LOCATIONS. SOME CLOUDINESS WILL LINGER INTO THE AFTERNOON, AND
WITH THIS IN MIND, AS WELL AS CONSIDERING THE REMAINING SNOWPACK
ACROSS THE REGION, WE UNDERCUT MET/MAV GUIDANCE BY A COUPLE OF
DEGREES ACROSS THE FORECAST AREA WITH REGARD TO MAXIMUM
TEMPERATURES. WE ANTICIPATE HIGHS TO MAINLY BE IN THE MIDDLE TO
UPPER 30S FOR THE FORECAST AREA, EXCEPT SOME LOWER 40S ACROSS
SOUTHERN NJ AND INTO THE DELMARVA, WITH COLDER UPPER 20S/LOWER 30S
REMAINING INTO THE POCONOS.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 AM MONDAY/...
BY SUNDAY NIGHT, THE FRONT AND ALL OF ITS PRECIPITATION WILL HAVE
PULLED WELL AWAY FROM THE AREA, AND THE NIGHT IS EXPECTED TO BE
PRECIPITATION FREE. THE ONLY EXCEPTION TO THIS IS THE SLIGHT
CHANCE FOR SOME LAKE EFFECT STREAMERS TO AFFECT THE POCONOS. SO
OVERALL, WE EXPECT A PARTLY TO MOSTLY CLOUDY NIGHT WITH COOL
TEMPERATURES. WITH THE CLOUDS AND WIND EXPECTED, TEMPERATURE
SHOULD NOT DROP SIGNIFICANTLY.
&&
.LONG TERM /MONDAY THROUGH SATURDAY/...
UPDATED DISCUSSION TO FOLLOW.
MONDAY WILL BE ANOTHER COLD AND BREEZY DAY. WITH LOW THICKNESSES
AND 925 MB TEMPERATURES, TEMPERATURES WILL RANGE FROM THE 20S
ACROSS THE SOUTHERN HALF, TO THE TEENS ACROSS THE NORTHERN HALF,
AND SINGLE DIGITS FAR NORTH. THIS WILL CREATE LOW WIND CHILLS
THROUGH THE DAY, IN THE SINGLE DIGITS FOR MUCH OF THE AREA, TO
BELOW ZERO FOR THE COLDEST. THE COLD TEMPERATURES WILL CONTINUE
INTO MONDAY NIGHT, WITH MOST PLACES IN THE SINGLE DIGITS, TO MINUS
SINGLE DIGITS IN SOME AREAS. ALTHOUGH HIGH PRESSURE BUILDS ACROSS
THE AREA, THERE WILL BE SOME WIND THAT WILL KEEP THE LOW WIND
CHILLS IN THE SINGLE DIGITS FOR MUCH OF THE AREA, TO BELOW ZERO
FOR THE COLDEST.
ON TUESDAY, THE HIGH PRESSURE BUILDS OFFSHORE WHICH WILL SWITCH
WINDS TO A MORE SOUTHERLY DIRECTION, HELP MODERATING TEMPERATURES
A FEW DEGREES. HOWEVER, IT WILL STILL BE WELL BELOW NORMAL. NO
PRECIPITATION IS EXPECTED AS THE AIR REMAINS DRY STILL, ALTHOUGH
THERE IS A SLIGHT INCREASE AHEAD OF AN APPROACHING FRONTAL
BOUNDARY.
A COLD FRONT IS FORECAST TO MOVE ACROSS THE AREA LATE TUESDAY
NIGHT INTO WEDNESDAY MORNING. THE GFS HAS SOME LIGHT QPF MOVING
ACROSS THE AREA, WHILE THE ECMWF DOES NOT. THERE IS NOT A LOT OF
MOISTURE OR ASSOCIATED LIFT FORECAST EITHER WAY, SO WE WILL ONLY
KEEP A SMALL CHANCE OF SNOW OVERNIGHT INTO WEDNESDAY, MAINLY FOR
THE NORTHERN HALF OF THE AREA.
ON WEDNESDAY NIGHT INTO THURSDAY, AN AREA OF LOW PRESSURE IS
FORECAST TO DEVELOP ALONG THE AFOREMENTIONED FRONTAL BOUNDARY TO
OUR SOUTH. ANY ASSOCIATED PRECIPITATION IS EXPECTED TO REMAIN
MOSTLY TO OUR SOUTH, BUT THERE IS A SLIGHT CHANCE THAT SOME SNOW
MAY MAKE ITS WAY INTO OUR FAR SOUTHERN AND SOUTHEASTERN AREAS. SO
WE WILL KEEP A SLIGHT CHANCE OF SNOW.
COLD TEMPERATURES RETURN BEHIND THIS FRONTAL BOUNDARY FOR THE END
OF THE WEEK. ESPECIALLY AS HIGH PRESSURE MOVES INTO THE AREA
THURSDAY NIGHT INTO FRIDAY. LOWS THURSDAY NIGHT WILL LIKELY GET
INTO THE SINGLE DIGITS TO BELOW ZERO AGAIN. ANOTHER PERIOD OF
SINGLE DIGIT TO BELOW ZERO WIND CHILLS IS EXPECTED WEDNESDAY NIGHT
THROUGH FRIDAY MORNING.
&&
.AVIATION /09Z SUNDAY THROUGH THURSDAY/...
THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG,
KILG, KMIV, KACY AND SURROUNDING AREAS.
EARLY MORNING...IFR CONDITIONS ARE IN PLACE ACROSS THE REGION AND
ARE EXPECTED TO LAST THROUGH THE EARLY MORNING HOURS. ALL SITES
FROM THE COAST TO THE DELAWARE VALLEY REGION HAVE TRANSITIONED
OVER TO RAIN, EXCEPT KABE AND KRDG WHERE LIGHT SNOW OR SOME
FREEZING RAIN IS EXPECTED BEFORE THE PRECIPITATION ENDS AROUND
DAYBREAK. IN FACT, PRECIPITATION IS FORECAST TO END FROM WEST TO
EAST ACROSS THE REGION BETWEEN ABOUT 1000Z AND 1300Z. WINDS ARE
EXPECTED TO REMAIN LIGHT, MAINLY OUT OF THE SOUTHWEST, OR PERHAPS
GO LIGHT AND VARIABLE FOR A TIME.
REST OF SUNDAY...WHILE PRECIPITATION ENDS EARLY, THE LOWER
CIGS/VSBYS, MAINLY IN THE IFR RANGE, ARE EXPECTED TO REMAIN
THROUGH AT LEAST THE MORNING. WHEN EXACTLY THE LOWER CONDITIONS
WILL BREAK WITH A RETURN TO VFR IS A TRICKY FORECAST AT THIS TIME,
AND THERE ARE DIFFERENCES IN THE GUIDANCE WITH RESPECT TO THIS
OCCURRENCE. FOR NOW, WE HAVE KEPT AN IMPROVEMENT TO VFR BETWEEN
AROUND 16Z TO 18Z, BUT THIS IS A LOW CONFIDENCE FORECAST AS THE
NOTICEABLE PUSH OF COLD, DRY AIR INTO THE REGION DOES NOT OCCUR
UNTIL SUNDAY EVENING/NIGHT. WINDS THROUGH THE DAYTIME SUNDAY ARE
EXPECTED TO BECOME MORE WESTERLY AND THEN NORTHWESTERLY, REMAINING
MOSTLY IN THE 4 TO 8 KNOT RANGE.
OUTLOOK...
SUNDAY NIGHT AND MONDAY...VFR EXPECTED. GUSTY NORTHWEST WINDS
20-25 KNOTS.
MONDAY NIGHT AND TUESDAY...VFR EXPECTED.
TUESDAY NIGHT AND WEDNESDAY...SLIGHT CHANCE OF SNOW SHOWERS.
LOWER CIGS/VSBYS POSSIBLE WITH ANY SHOWERS, OTHERWISE, MOSTLY VFR
EXPECTED. GUSTY NORTHWEST WINDS 20-25 KNOTS DURING THE DAY.
WEDNESDAY NIGHT-THURSDAY...VFR EXPECTED.
&&
.MARINE...
**SINCE MUCH OF DELAWARE BAY IS COVERED BY ICE WE WILL CONTINUE
TO ADD THE PHRASING "ON ICE FREE WATERS" FOR THE FIRST FOUR
PERIODS OF THE FORECAST**
THE SMALL CRAFT ADVISORY REMAINS IN EFFECT FOR THE OCEAN WATERS
MAINLY FOR SEAS WITH THE SOUTHERLY FLOW INTO SUNDAY. WE KEPT WINDS
AND SEAS BELOW SMALL CRAFT ADVISORY CRITERIA IN DELAWARE BAY.
OUTLOOK...
SUNDAY NIGHT...SMALL CRAFT ADVISORY ON THE OCEAN EXTENDED THROUGH
SUNDAY NIGHT AS WINDS ARE EXPECTED TO INCREASE. WINDS MAY GET
CLOSE ON THE DELAWARE BAY LATE SUNDAY NIGHT INTO MONDAY, SO AN
ADVISORY MAY BE NEEDED. LIGHT FREEZING SPRAY LIKELY.
MONDAY THROUGH MONDAY NIGHT...SMALL CRAFT ADVISORY MAY NEED TO BE
EXTENDED IN FUTURE FORECASTS AS WINDS MAY REMAIN ELEVATED INTO
EARLY MONDAY NIGHT. FREEZING SPRAY LIKELY
TUESDAY THROUGH THURSDAY...WINDS AND SEAS MAY GET CLOSE TO
ADVISORY LEVELS OVERNIGHT TUESDAY NIGHT/WEDNESDAY MORNING AND
AGAIN OVERNIGHT WEDNESDAY NIGHT/THURSDAY MORNING. OTHERWISE
CONDITIONS SHOULD STAY BELOW ADVISORY LEVELS
&&
.CLIMATE...
DAILY RECORD MIN TEMPS WERE SET ON FEB 21, 2015 AT: ACY, ILG,
ABE, TTN, GED AND MPO THIS MORNING. HERE ARE THE PARTICULARS...
POR | SITE | PREV RECORD MINT (YEAR)| NEW RECORD MINT (YEAR)
1874 | KACY | 3 (1968) | -6 (2015)
1894 | KILG| 6 (1968,1934) | 3 (2015)
1922 | KABE| 0 (1936) | -3 (2015)
1865 | KTTN | 6 (1893) | 3 (2015)
1948 | KGED | 8 (1959) | -4 (2015)
1901 | KMPO | -8 (1993) | -10(2015)
NOTE: POR= PERIOD OF RECORD (YEAR THE OFFICIAL CLIMATE OBS BEGAN)
ALSO, THE -6F ON FEB 21, 2015 IS THE COLDEST TEMPERATURE RECORDED
AT ATLANTIC CITY SINCE FEBRUARY 5, 1996 AND THE LATEST OCCURRENCE
OF A SUB-ZERO TEMPERATURE IN THE SEASON ON RECORD. THE PREVIOUS
LATEST SUB-ZERO DAY IN WINTER/SPRING WAS JUST SET YESTERDAY, AND
BEFORE THAT, IT WAS FEBRUARY 18TH WHEN THE LOW WAS -7F ON THAT
DATE IN 1979.
&&
.PHI WATCHES/WARNINGS/ADVISORIES...
PA...WINTER STORM WARNING UNTIL 6 AM EST EARLY THIS MORNING FOR
PAZ060>062-101>103-105.
WINTER STORM WARNING UNTIL 9 AM EST THIS MORNING FOR PAZ070-
071-104-106.
WINTER WEATHER ADVISORY UNTIL 6 AM EST EARLY THIS MORNING FOR
PAZ054-055.
NJ...WINTER STORM WARNING UNTIL 6 AM EST EARLY THIS MORNING FOR
NJZ007>010-015.
FREEZING RAIN ADVISORY UNTIL 9 AM EST THIS MORNING FOR NJZ021-
022.
WINTER STORM WARNING UNTIL 9 AM EST THIS MORNING FOR
NJZ012>014-016>020-026-027.
WINTER WEATHER ADVISORY UNTIL 6 AM EST EARLY THIS MORNING FOR
NJZ001.
DE...FREEZING RAIN ADVISORY UNTIL 9 AM EST THIS MORNING FOR DEZ002.
WINTER STORM WARNING UNTIL 9 AM EST THIS MORNING FOR DEZ001.
MD...WINTER STORM WARNING UNTIL 6 AM EST EARLY THIS MORNING FOR
MDZ008.
FREEZING RAIN ADVISORY UNTIL 9 AM EST THIS MORNING FOR MDZ015.
WINTER STORM WARNING UNTIL 9 AM EST THIS MORNING FOR MDZ012.
MARINE...SMALL CRAFT ADVISORY UNTIL 6 PM EST MONDAY FOR ANZ450>455.
SMALL CRAFT ADVISORY FROM 6 AM TO 6 PM EST MONDAY FOR ANZ430-
431.
&&
$$
SYNOPSIS...ROBERTSON
NEAR TERM...KLINE
SHORT TERM...GIGI/ROBERTSON
LONG TERM...ROBERTSON
AVIATION...KLINE/ROBERTSON
MARINE...GIGI/ROBERTSON
CLIMATE...
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
337 AM EST SUN FEB 22 2015
.SYNOPSIS...
THE LOW PRESSURE THAT BROUGHT THE SNOW TO THE REGION WILL TRACK
WELL OFF THE EAST COAST TODAY AS YET ANOTHER ARCTIC FRONT CROSSES
THE REGION THIS EVENING. BITTERLY COLD AIR WILL FOLLOW FOR MONDAY
INTO TUESDAY WITH SUB ZERO TEMPERATURES AND AT TIMES DANGEROUSLY
COLD WIND CHILLS. SOME MODERATION IS EXPECTED TUESDAY AND
ESPECIALLY WEDNESDAY AS HIGHS REACH INTO THE 20S AND LOWER 30S.
&&
.NEAR TERM /THROUGH MONDAY/...
THE LAST OF THE LIGHT SNOW AND FLURRIES WAS EXITING NE PA AND
SULLIVAN COUNTY AT THIS TIME AS AN UPPER LEVEL WAVE RIPPLES INTO
NY AND PA ERLY THIS MORNING. THERE HAS BEEN NO REPORTS OF FREEZING
DRIZZLE ANYWHERE IN CNTRL OR WRN NY OR NRN AND WRN PA AND LOOKING
AT THE SOUNDINGS I REALLY DON/T SEE ANY POTENTIAL. SFC WET BULB
TEMPERATURES WERE RUNNING ARND -7C AND WITH UPLIFT IT WUD BE COLD
ENUF FOR SOME ICE CRYSAL GROWTH. MODELS ARE SHOWING SUBSDC BEHIND
THIS UPPER WAVE ANYWAY SO NOT EXPECTING ANY WIDESPREAD FREEZING
DRIZZLE. THUS HAVE DROPPED WINTER WEATHER ADVISORY.
THE REST OF THE MORNING INTO THE AFTERNOON LOOKS TO BE CLOUDY AS
CAA BEGINS AND TRAPS MOISTURE UNDER A SHARP INVERSION ARND 900
MB. ANOTHER ARCTIC FRONT IS POISE TO PASS THRU THE REGION THIS
EVENING SO MUCH OF THE AFTERNOON WILL BE ALMOST SEASONABLE IN
TEMPERATURES. ARCTIC FRONT PASSES BY THIS EVENING. SOUNDINGS
SUGGEST THAT THE INVERSION RISES TO ABT 850 MB WHEN THE ARCTIC
PASSES BY WITH MINIMAL CAPE. THERE CUD BE SOME SNOW SQUALLS BUT
AT THIS TIME IT DOESN`T LOOK LIKE A MAJOR SNOW SQUALL EVENT.
HOWEVER...IT WILL DEPEND ON HOW WARM IT GETS THIS AFTERNOON.
CONVECTION ALLOWING MODELS THIS FAR OUT(WRF_NMM AND WRF_ARW) ARE
NOT SHOWING ANYTHING SIGNIFICANT EITHER. IT WILL BE INTERESTING TO
SEE IF THE RAP AND HRRR CATCH ONTO SOMETHING WHEN THEY GET TO THIS
EVENINGS TIME PERIOD. THIS IS SOMETHING TO PASS ONTO THE NEXT
SHIFT.
AFTER ARCTIC FRONT PASSES BY...THE USUAL 290 DEGREE LES SETS UP
BUT IT LIKELY WILL BE TOO DRY FOR ANY MAJOR ACCUMULATIONS
DOWNWIND...MAYBE SEVERAL INCHES AT BEST. BIG STORY WILL BE ANOTHER
SHOT OF ARCTIC AIR ON FAIRLY STRG NW WINDS. MINS MONDAY AM WILL BE
FROM ZERO TO 15 BELOW IN NY STATE WITH WIND CHILLS BETWEEN 20 AND
30 BELOW ZERO AS IT STANDS NOW. SO HAVE HOISTED A WIND CHILL WATCH
FOR TONIGHT AND MONDAY MORNING TO GIVE EVERYONE A HEAD`S UP ON
ANOTHER COLD MONDAY MORNING. THE WC WATCH IS FOR NY COUNTIES
EXCEPT SULLIVAN CO AND FOR NRN PA COUNTIES IN ERN PA.
MONDAY WILL BE ANOTHER COLD AND WINDY DAY WITH TEMPERATURES
STRUGGLING TO GET OUT ABOVE ZERO IN NRN NY AND BARELY REACHING 10
DEGREES IN NE PA.
&&
.SHORT TERM /MONDAY NIGHT THROUGH TUESDAY NIGHT/...
FOR MONDAY NIGHT...YET ANOTHER BRUTALLY COLD NIGHT IS IN STORE AS
THIS HISTORICALLY COLD FEBRUARY CONTINUES. MINS LIKELY WILL DROP
TO 5 BELOW TO 20 BELOW OR LOWER. THEN TUESDAY THERE IS A SOUTHERLY
FLOW IN ADVANCE OF ANOTHER SYSTEM TRACKING INTO QUEBEC. THIS WILL
LEAD TO SOME MODERATION AND A CHANCE OF SNOW SHOWERS BY TUESDAY
NIGHT.
&&
.LONG TERM /WEDNESDAY THROUGH SATURDAY/...
EASTERN TROF IS EXPECTED TO CONTINUE THROUGH THE END OF THE WEEK
WITH RISING HEIGHTS AND PERHAPS ZONAL FLOW BY NEXT WEEKEND.
ON WEDNESDAY THE NEXT ARCTIC FRONT WILL PASS THROUGH THE AREA WITH
SCATTERED SNOW SHOWERS AND MORE FRIGID AIR. WEDNESDAY NIGHT
THROUGH FRIDAY NIGHT TEMPS WILL RUN 15 TO 25 DEGREES BELOW NORMAL.
NORTHWEST FLOW FOLLOWING THE FRONT MAY PRODUCE SOME SCATTERED LAKE
EFFECT SNOW SHOWERS AND FLURRIES BUT NOTHING REAL SIGNIFICANT DUE
TO SHORT FETCH AND PLENTY OF ICE ON LAKE ONTARIO. IN GENERAL A
FAIRLY QUIET BUT COLD PERIOD. SATURDAY AND SUNDAY A SYSTEM IN THE
MID ATLANTIC MAY BRUSH THE FA ESPECIALLY THE SOUTHERN PORTION,
INCLUDED CHC/SLIGHT CHC POPS.
&&
.AVIATION /08Z SUNDAY THROUGH THURSDAY/...
SNOW HAS ENDED ACROSS ALL TERMINALS EXCEPT FOR KAVP WHERE MVFR
CONDITIONS IN LIGHT SNOW WILL CONTINUE UNTIL 08Z. ABUNDANT LOW
LEVEL MOISTURE AND WEAK MIXING WILL RESULT IN LOW MVFR CONDITIONS
THROUGH MID MORNING AT ALL TERMINALS. AT KRME/KITH/KBGM, IFR CIGS
WILL BE POSSIBLE BETWEEN 09Z-13Z. BY MID MORNING SOME IMPROVEMENT
IS LIKELY BUT MODEL SOUNDINGS SHOW LOW LEVEL MOISTURE TRAPPED
UNDER AN INVERSION THEREFORE CONTINUED WITH MVFR CIGS THROUGH THE
DAYLIGHT HOURS. THIS EVENING AN ARCTIC FRONT WILL PASS THROUGH
BRINGING SNOW SHOWERS AND MORE MVFR CONDITIONS.
LIGHT AND VARIABLE WINDS BECOMING NW BY MID MORNING AROUND 5-8
KNOTS.
.OUTLOOK...
MON...MVFR/IFR RESTRICTIONS PSBL IN SNOW SHWRS.
MON NGT-TUE...VFR.
TUE NGT-WED...RESTRICTIONS PSBL AGN IN SNOW SHWRS/LGT SNOW...ESP CNY.
WED NGT-THU...MAINLY VFR.
&&
.BGM WATCHES/WARNINGS/ADVISORIES...
PA...WIND CHILL WATCH FROM LATE TONIGHT THROUGH MONDAY MORNING FOR
PAZ038-039.
NY...WIND CHILL WATCH FROM LATE TONIGHT THROUGH MONDAY MORNING FOR
NYZ009-015>018-022>025-036-037-044>046-055>057.
&&
$$
SYNOPSIS...DJN
NEAR TERM...DJN
SHORT TERM...DJN
LONG TERM...RRM
AVIATION...RRM
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
312 AM EST SUN FEB 22 2015
.SYNOPSIS...
HIGH PRESSURE OFFSHORE WILL CIRCULATE MILD AIR INTO THE REGION
WITH TEMPERATURES IN THE 60S TODAY. A GOOD CHANCE OF SIGNIFICANT
RAIN IS EXPECTED TONIGHT AND ON MONDAY AS GULF MOISTURE IS LIFTED
AHEAD OF AN UPPER TROUGH MOVING ACROSS THE EAST COAST. COLD AIR
WILL RETURN LATE MONDAY AS ARCTIC HIGH PRESSURE BUILDS IN. COLD
AND UNSETTLED WEATHER IS EXPECTED MUCH OF THE UPCOMING WEEK AS
CHILLY HIGH PRESSURE AND GULF MOISTURE INTERACT.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 955 PM SATURDAY...THE LINE OF SHOWERS HAS DEVELOPED FROM
BRUNSWICK INTO WESTERN PENDER COUNTIES. THE HRRR 23 AND 00 UTC RUN
BOTH ARE SHOWING THE PRECIPITATION MOVING OFF THE COAST AFTER 05
UTC. AS THIS MOVES OUT THE THE NEXT AREA OF RAIN AHEAD OF THE COLD
FRONT THAT WILL BE ENTERING WESTERN NORTH CAROLINA WILL MOVE INTO
THE WESTERN PORTIONS OF THE FORECAST AREA JUST BEFORE SUNRISE.
TEMPS OVERNIGHT WILL REMAIN WARM WITH MID 40S INLAND AND NEAR 50
CLOSER TO THE COAST.
&&
.SHORT TERM /MONDAY THROUGH TUESDAY NIGHT/...
AS OF 3 AM SUNDAY...PERIOD BEGINS WITH COLD FRONT JUST SOUTH OF THE
AREA AND HIGH PRESSURE BUILDING IN FROM THE NORTH. STARTING TO LOOK
MORE AND MORE LIKE MEANINGFUL MOISTURE WILL EXIT THE AREA BEFORE THE
COLD AIR ARRIVES. FORECAST SOUNDINGS DO SUGGEST A BRIEF PERIOD OF
TIME WHERE SLEET IS POSSIBLE ALONG THE NC COAST MON AFTERNOON BUT
THE ISSUE IS FORCING. ABUNDANT MOISTURE WILL BE PRESENT BUT POST
SHORTWAVE SUBSIDENCE WILL RESIST UPWARD MOTION AND THERE IS VERY
LITTLE IN THE WAY OF ISENTROPIC LIFT. GIVEN THE AMOUNT OF LOW LEVEL
SATURATION THINK THERE IS LIKELY TO BE SOME AFTERNOON PRECIP ALONG
THE COAST BUT LIKELIHOOD OF MEASURABLE AMOUNTS AFTER 18Z IS QUITE
LOW SO PLAN TO TREND DOWN MON AFTERNOON POP.
SURFACE HIGH BUILDING IN FROM THE NORTHWEST MON NIGHT WEAKENS AS IT
SHIFTS EAST ON TUE. FRONT REMAINS STALLED WELL SOUTH OF THE AREA TUE
BUT TUE NIGHT IT WILL TRY AND LIFT BACK NORTH. ALTHOUGH WEST TO
SOUTHWEST FLOW ALOFT WILL CONTINUE SPREADING MID LEVEL MOISTURE OVER
THE AREA TUE THE LACK OF FORCING COMBINED WITH LOW LEVEL DRY AIR
WILL WORK TO KEEP THE REGION DRY. NOT QUITE READY TO PULL POP FROM
THE TUE FORECAST BUT THINK ONLY SLGT CHC IS WARRANTED ALONG THE
COAST WITH INLAND AREAS REMAINING DRY. AS THE FRONT TRIES TO RETURN
NORTH SOME LIGHT RAIN MAY SPREAD BACK OVER THE COAST. HOWEVER...THE
GUIDANCE HAS BEEN GENERALLY TRENDING DRIER AND THERE IS A LACK OF OF
FORCING ALONG WITH A FAIR AMOUNT OF LOW LEVEL DRY AIR. TEMPERATURES
WILL RUN BELOW TO WELL BELOW CLIMO THROUGH THE PERIOD.
&&
.LONG TERM /WEDNESDAY THROUGH SATURDAY/...
AS OF 3 AM SUNDAY...EXTENDED PERIOD REMAINS VERY MUCH IN QUESTION.
MID LEVEL TROUGH WILL COVER MUCH OF THE CONUS WITH THE SOUTHERN
STREAM BECOMING MORE ACTIVE. DECAYING SURFACE BOUNDARY WILL BE
STALLED SOUTH OF THE AREA AT THE START OF THE PERIOD BUT SOUTHERN
STREAM SYSTEM CROSSING THE NORTHERN GULF OF MEXICO MIDWEEK WILL LIFT
THE BOUNDARY CLOSER TO THE COAST. PROXIMITY OF THE BOUNDARY AND THE
LOW PRESSURE THAT WILL EVENTUALLY RIDE UP IT TO THE COAST WED INTO
THU REMAINS A SIGNIFICANT CHALLENGE. THE FATE OF THE WED/THU
FORECAST RIDES ON THE LOCATION OF THESE FEATURES AND WILL DETERMINE
IF ANY PRECIP FALLS ACROSS THE AREA AND IF IT FALLS WHETHER IT WILL
BE LIQUID OR FROZEN. THE LATEST GFS HAS TRENDED DRIER...KEEPING THE
BOUNDARY AND THE LOW FARTHER OFF THE COAST. THE LATEST ECMWF HAS A
STRONGER SOUTHERN STREAM SYSTEM...THOUGH NOT AS STRONG AS THE 12Z
SAT RUN...CAUSING MORE MID LEVEL AMPLIFICATION. THIS STRENGTHENS THE
SURFACE INFLECTION...PULLING THE LOW/BOUNDARY CLOSER TO THE COAST.
THE DIFFERENCE BETWEEN THE 2 SOLUTIONS IS NOT VAST BUT THE
IMPLICATIONS TO THE FORECAST ARE SIGNIFICANT. GIVEN THE LEVEL OF
UNCERTAINTY WILL NOT STRAY FAR FROM INHERITED FORECAST BUT NOTE THAT
THERE CONTINUES TO BE POTENTIAL FOR FROZEN PRECIP WED NIGHT/THU
MORNING...MAINLY SLEET OR A MIX OF RAIN/SNOW...SO WENT AHEAD AND
ADDED IT TO THE FORECAST.
END OF NEXT WEEK WILL ALSO BE QUITE INTERESTING. AS THE MID WEEK
SYSTEM EXITS NORTHEAST ARCTIC HIGH BUILDS IN FROM THE NORTH. FRI MAY
END UP DRY AS SPRAWLING HIGH HELPS SPREAD COOL/DRY AIR DOWN THE EAST
COAST. MOISTURE WILL SLOWLY RETURN LATE FRI AND FRI NIGHT AS COASTAL
TROUGH FIRST DEVELOPS THEN STRENGTHENS. THERE WILL BE A PERIOD OF
TIME FRI NIGHT AND SAT WHERE LIGHT FROZEN PRECIP LOOKS TO BE A
POSSIBILITY. COASTAL TROUGH TRIES TO MOVE ONSHORE SAT INTO SAT NIGHT
ACCOMPANIED BY CLOUDS AND SHOWERS. TEMPERATURES WILL REMAIN BELOW
CLIMO THROUGH THE PERIOD.
&&
.AVIATION /08Z SUNDAY THROUGH THURSDAY/...
AS OF 06Z...LINGERING LOW CLOUDS ARE LEFT IN THE WAKE OF SHOWERS
THIS PAST EVNING...THAT WERE PRIMARILY ALONG THE COASTAL
TERMINALS. LOW CLOUDS AND AREAS OF FOG WILL MAINLY BE A CONCERN
ALONG THE COASTAL TERMINALS AND WILL BRING MVFR...AND POSSIBLY IFR
IN AS A TEMPO GROUP AFTER 06Z. FEELING IS THAT CEILING/VSBY COULD
BE PROBLEMATIC DURING THE EARLY MORNING HOURS ACROSS THESE
TERMINALS. THE INLAND COULD ALSO SEE SOME PATCHY FOG WITH MOISTURE
FROM EVENING RAIN AND SOME CLEARING AND LIGHT WINDS...WILL MENTION
MVFR THERE AS WELL. OTHERWISE NO CHANGES TO EARLIER TAFS FOR THE
REMAINDER OF THE DAY AS MODEL BRINGING IN A CHANCE OF PCPN ACROSS
THE INLAND TERMINALS DURING THE AFTERNOON AND TO THE COAST BY
EVENING.
EXTENDED OUTLOOK...A SERIES OF WEAK SYSTEMS WILL MOVE THROUGH THE
REGION THROUGHOUT THE FORECAST PERIOD...WITH PERIODS OF LIGHT PRECIP
POSSIBLE EACH DAY.
&&
.MARINE...
NEAR TERM /THROUGH TONIGHT/...
AS OF 955 PM SATURDAY...SOUTH TO SOUTHEAST WIND FLOW CONTINUES AND
BUOYS ARE SHOWING WINDS 10 TO 15 KNOTS NEAR SHORE AND AROUND 25
KNOTS AT FRYING PAN. SEAS AT FRYING PAN ARE SHOWING 8 FEET WITH
THE HARBOR BUOY AT THE MOUTH OF THE CAPE FEAR RIVER NOW AT 5.5
FEET. WILL CONTINUE SMALL CRAFT THROUGH 7 AM FOR ENTIRE WATERS AND
ONLY FOR WATERS NORTH OF LITTLE RIVER INLET BY 10 AM. ALSO WITH
THE WARMER AIR MOIST AIR WE CAN EXPECT SOME PATCHY SEA FOG
OVERNIGHT.
SHORT TERM /MONDAY THROUGH TUESDAY NIGHT/...
AS OF 3 AM SUNDAY...HEADLINES ALL BUT CERTAIN MON AND MON NIGHT AS
ARCTIC HIGH BUILDS IN AND PINCHES THE GRADIENT. NORTHERLY WINDS WILL
APPROACH 25 KT AND SEAS BUILD TO 8 FT IN SOME AREAS. WINDS START
DECREASING TUE AS ELONGATED SURFACE RIDGE AXIS MOVES TO THE COAST
AND GRADIENT RELAXES. LIGHT WINDS LATE TUE CONTINUE TUE NIGHT AS THE
WEAK HIGH EXITS NORTHEAST AND WINDS BACK TO WEST-SOUTHWEST. SEAS
FALL TO 3 TO 5 FT LATER TUE AND 2 TO 4 FT TUE NIGHT.
LONG TERM /WEDNESDAY THROUGH THURSDAY/...
AS OF 3 AM SUNDAY...LIGHT WESTERLY FLOW WEDNESDAY WILL BECOME
NORTH-NORTHEAST THU. ILL DEFINED GRADIENT WED WILL KEEP SPEEDS UNDER
10 KT FOR MUCH OF THE DAY BUT LOW PRESSURE MOVING EAST ALONG
BOUNDARY STALLED SOUTH OF THE WATERS WILL TIGHTEN UP THE GRADIENT
WED NIGHT AND THU...INCREASING SPEEDS TO 15 TO 20 KT WED NIGHT AND A
SOLID 20 KT THU. GRADIENT REMAINS PINCHED THU NIGHT AS ANOTHER WEAK
SURFACE WAVE PASSES EAST OF THE WATERS. ALTHOUGH SPEEDS ARE
CURRENTLY FORECAST TO REMAIN JUST UNDER SCA HEADLINE THRESHOLDS SEAS
WILL LIKELY BUILD OVER 6 FT DURING THE LATER HALF OF THE PERIOD SO
SCA MAY BE REQUIRED.
&&
.ILM WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
NC...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 6 AM EST EARLY THIS MORNING FOR
AMZ254-256.
SMALL CRAFT ADVISORY UNTIL 10 AM EST THIS MORNING FOR AMZ250-
252.
&&
$$
NEAR TERM...DCH
SHORT TERM...III
LONG TERM...III
AVIATION...DCH/MAC
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
1231 AM EST SUN FEB 22 2015
.SYNOPSIS...
HIGH PRESSURE OFFSHORE WILL CIRCULATE MILD AIR INTO THE REGION
WITH TEMPERATURES IN THE 60S SUNDAY. A GOOD CHANCE OF SIGNIFICANT
RAIN IS EXPECTED SUNDAY NIGHT AND MO MONDAY...AS GULF MOISTURE IS
LIFTED AHEAD OF AN UPPER TROUGH MOVING ACROSS THE EAST COAST. COLD
AIR WILL RETURN LATE MONDAY AS ARCTIC HIGH PRESSURE BUILDS IN.
COLD AND UNSETTLED WEATHER IS EXPECTED MUCH OF THE UPCOMING WEEK
AS CHILLY HIGH PRESSURE AND GULF MOISTURE INTERACT.
&&
.NEAR TERM /UNTIL 6 AM THIS MORNING/...
AS OF 955 PM SATURDAY...THE LINE OF SHOWERS HAS DEVELOPED FROM
BRUNSWICK INTO WESTERN PENDER COUNTIES. THE HRRR 23 AND 00 UTC RUN
BOTH ARE SHOWING THE PRECIPITATION MOVING OFF THE COAST AFTER 05
UTC. AS THIS MOVES OUT THE THE NEXT AREA OF RAIN AHEAD OF THE COLD
FRONT THAT WILL BE ENTERING WESTERN NORTH CAROLINA WILL MOVE INTO
THE WESTERN PORTIONS OF THE FORECAST AREA JUST BEFORE SUNRISE.
TEMPS OVERNIGHT WILL REMAIN WARM WITH MID 40S INLAND AND NEAR 50
CLOSER TO THE COAST.
&&
.SHORT TERM /6 AM THIS MORNING THROUGH MONDAY NIGHT/...
AS OF 3 PM SATURDAY...PRIMARY WEATHER HEADLINES SUNDAY AND MONDAY
ARE PROSPECTS OF A DECENT SOAKER OF A RAIN EVENT SUNDAY NIGHT TO
MONDAY MORNING...FOLLOWED BY A VERY SLIGHT CHANCE OF A FEW SNOW
FLURRIES LATE ON MONDAY.
GULF OF MEXICO TAP TO PLAY A NOTABLE ROLE IN ELEVATING DEEP COLUMN
MOISTURE 18Z SUN-00Z TUE...WITH STORM TOTAL CALCULATIONS PROGGING
ABOUT AN INCH OF RAINFALL ACROSS NE SC AND SE NC. THE BULK OF THIS
APT TO FALL AS 6Z-18Z MONDAY AS ISENTROPIC OMEGA INCREASES.
STRONG COLD AIR ADVECTION MONDAY AS HIGH PRESSURE OF ARCTIC BIRTH
BARGES IN...WITH DIURNAL TEMPERATURE RANGES NARROW IN THE BATTLE
WITH DAYTIME WARMING. VERY COLD AIR LATER IN THE DAY MONDAY AND
NIGHT ON THE HEELS OF EGRESSING MOISTURE...COULD OPEN A WINDOW
OF BRIEF SNOW FLURRIES. DEEP COLD CONVECTION UNLIKELY SINCE DRY
AIR ENCROACHMENT ABOVE 850 MB WILL ALREADY BE UNDERWAY.
MILDEST PERIOD SUNDAY AFTERNOON WITH 60S WIDESPREAD AWAY FROM THE
IMMEDIATE BEACHES. COLDEST PERIOD EARLY TUES AS ARCTIC AIR SPILLS
INTO THE CAROLINAS...MINIMUMS DAYBREAK TUESDAY 24-31 DEGREES.
&&
.LONG TERM /TUESDAY THROUGH SATURDAY/...
AS OF 345 PM SATURDAY...SUBTLE PATTERN SHIFT THROUGH THE EXTENDED
WILL LEAD TO CONTINUED COLD AIR ENTRENCHED ACROSS THE EAST...WITH
THE SOUTHERN STREAM BECOMING THE DOMINANT WEATHER MAKER THROUGH THE
WEEK.
LONG-WAVE TROUGH WHICH HAS PLAGUED THE EASTERN CONUS FOR THE PAST
MONTH WILL REMAIN...BUT IN A LESS AMPLIFIED SETUP. THE TROUGH WILL
BROADEN SUCH THAT IT EXTENDS WELL INTO THE ATLANTIC...AND WHILE THIS
WILL DO LITTLE TO REMEDY THE COLD...IT WILL KEEP MOST OF THE
PRECIPITATION SUPPRESSED TO THE SOUTH. COLD FRONT WILL BE STALLED
WELL SOUTH OF THE AREA TUESDAY MORNING...AND ALONG THIS BAROCLINIC
GRADIENT IS WHERE A SERIES OF SHORTWAVES AND WEAK LOW PRESSURES WILL
ROTATE THROUGH THE WEEK. THIS KEEPS AT LEAST A SCHC OF
PRECIP...ESPECIALLY SE ZONES...THROUGH THE WEEK. TIMING OF THESE
INDIVIDUAL SHORTWAVES AND SURFACE REFLECTIONS IS DIFFICULT...SO WILL
MAKE LITTLE CHANGE TO INHERITED POP...AND KEEP A SCHC OF PRECIP
ALONG THE COAST/SOUTH THROUGH THE WEEK. LOCAL TOP-DOWN METHODOLOGY
DOES PRODUCE PERIODS OF R/S OR R/IP/ZR...PRETTY MUCH EACH DAY.
CONFIDENCE IS LOW IN TIMING...AND TEMPS WILL WARM ABOVE FREEZING
EACH AFTN SO HAVE OPTED TO KEEP ONLY LIQUID PRECIP FOR NOW THROUGH
THURSDAY. HOWEVER...NEED TO MENTION THAT THERE VERY WELL COULD BE
PERIODS OF WINTRY MIXED PRECIP...ALMOST ANY DAY THROUGH THE WEEK.
TEMPS TUE-FRI WILL REMAIN WELL BELOW NORMAL FOR THE
PERIOD...AVERAGING ABOUT 10 DEGREES BELOW CLIMO.
LATE IN THE PERIOD THINGS GET A LITTLE MORE INTERESTING AS A STRONG
SURFACE WEDGE RE-BUILDS DOWN THE COAST AHEAD OF A MORE SIGNIFICANT
LOW PRESSURE SYSTEM. GUIDANCE AGREES THAT A COASTAL TROUGH WILL
SHARPEN AND CLOSE OFF ON SATURDAY...BUT THE INTENSITY AND TRACK OF
THE LOW IS STILL VERY MUCH IN QUESTION. WITH THE STRONG COLD WEDGE
IN PLACE...WE COULD BE LOOKING AT A MIXED P-TYPE EVENT FRIDAY NIGHT
INTO SATURDAY...BUT GUIDANCE DOES SHOW A QUICK WARMUP SATURDAY WHICH
WOULD TRANSITION TO ALL RAIN. LOTS OF UNCERTAINTY AT THIS TIME
RANGE...BUT THIS CONTINUES TO BE SUPPORTED BY GUIDANCE REGARDLESS OF
THE STRICT PATTERN EVOLUTION. WITH TEMPS BELOW FREEZING AND CHC POP
WARRANTED...AFTER COLLABORATION WITH NEIGHBORS HAVE OPTED TO INCLUDE
THE ZR CREATED FROM TOP-DOWN FOR FRIDAY NIGHT INTO SATURDAY. STILL A
LOT CAN CHANGE...BUT FRIDAY NIGHT INTO SATURDAY COULD GET MESSY
ACROSS THE AREA.
&&
.AVIATION /06Z SUNDAY THROUGH THURSDAY/...
AS OF 06Z...LINGERING LOW CLOUDS ARE LEFT IN THE WAKE OF SHOWERS
THIS PAST EVNING...THAT WERE PRIMARILY ALONG THE COASTAL
TERMINALS. LOW CLOUDS AND AREAS OF FOG WILL MAINLY BE A CONCERN
ALONG THE COASTAL TERMINALS AND WILL BRING MVFR...AND POSSIBLY IFR
IN AS A TEMPO GROUP AFTER 06Z. FEELING IS THAT CEILING/VSBY COULD
BE PROBLEMATIC DURING THE EARLY MORNING HOURS ACROSS THESE
TERMINALS. THE INLAND COULD ALSO SEE SOME PATCHY FOG WITH MOISTURE
FROM EVENING RAIN AND SOME CLEARING AND LIGHT WINDS...WILL MENTION
MVFR THERE AS WELL. OTHERWISE NO CHANGES TO EARLIER TAFS FOR THE
REMAINDER OF THE DAY AS MODEL BRINGING IN A CHANCE OF PCPN ACROSS
THE INLAND TERMINALS DURING THE AFTERNOON AND TO THE COAST BY
EVENING.
EXTENDED OUTLOOK...A SERIES OF WEAK SYSTEMS WILL MOVE THROUGH THE
REGION THROUGHOUT THE FORECAST PERIOD...WITH PERIODS OF LIGHT PRECIP
POSSIBLE EACH DAY.
&&
.MARINE...
NEAR TERM /THROUGH TONIGHT/...
AS OF 955 PM SATURDAY...SOUTH TO SOUTHEAST WIND FLOW CONTINUES AND
BUOYS ARE SHOWING WINDS 10 TO 15 KNOTS NEAR SHORE AND AROUND 25
KNOTS AT FRYING PAN. SEAS AT FRYING PAN ARE SHOWING 8 FEET WITH
THE HARBOR BUOY AT THE MOUTH OF THE CAPE FEAR RIVER NOW AT 5.5
FEET. WILL CONTINUE SMALL CRAFT THROUGH 7 AM FOR ENTIRE WATERS AND
ONLY FOR WATERS NORTH OF LITTLE RIVER INLET BY 10 AM. ALSO WITH
THE WARMER AIR MOIST AIR WE CAN EXPECT SOME PATCHY SEA FOG
OVERNIGHT.
SHORT TERM /SUNDAY THROUGH MONDAY NIGHT/...
AS OF 3 PM SATURDAY...ADVISORIES MAY BE NEEDED EARLY SUNDAY AS
SEA HEIGHTS RECOVER FROM THE PRESENT SE WAVE-BUILDING FETCH. AN
ADVISORY WILL AGAIN BE NEEDED MOST IF NOT ALL OF MONDAY AS NORTH
WINDS RIP ACROSS THE WATERS...DUE TO AN ARCTIC HIGH TAKEOVER.
A WAVE DIRECTION TRANSITION TO BISECT THIS TIME PERIOD AS S WAVE
ENERGY TURNS TO N AND NE MONDAY AND BUILDS WAVE-HEIGHTS AT TO
ABOVE ADVISORY RANGE IN TANDEM WITH ADVISORY WINDS TO BOOT. NO
TSTMS EXPECTED BUT PATCHY FOG WILL PLAGUE THE WATERS EARLY SUNDAY.
LONG TERM /TUESDAY THROUGH THURSDAY/...
AS OF 345 PM SATURDAY...COLD FRONT WILL REMAIN STALLED JUST SOUTH OF
THE WATERS THROUGH THE EXTENDED...WHILE WAVES OF LOW PRESSURE MOVE
ALONG THIS BOUNDARY. THE PERIOD WILL BE BOOK-ENDED BY GUSTY N/NE
WINDS BOTH EARLY TUESDAY AND AGAIN LATE THURSDAY...AS THE GRADIENT
TIGHTENS NEAR LOW PRESSURE SYSTEMS MOVING WELL OFF THE COAST. SPEEDS
DURING THESE NE SURGES WILL BE AROUND 15-20 KT. WINDS EASE AND
BACK TO THE NW TUESDAY NIGHT AND THROUGH WEDNESDAY AS HIGH
PRESSURE RIDGES TOWARDS THE WATERS FROM THE NW...BEFORE AGAIN
INCREASING LATE THURSDAY AS MENTIONED ABOVE. SEAS WILL BE 3-5 FT
EARLY TUESDAY ON THE GUSTY NE WINDS...BEFORE EASING LATE TO 2-3 FT
AND REMAINING AT THESE AMPLITUDES THROUGH WEDNESDAY NIGHT. AS THE
WINDS RISE ON THURSDAY...SEAS BUILD AGAIN QUICKLY...AND AN
EXTENDED PERIOD OF SCA CONDITIONS MAY DEVELOP BEGINNING THURSDAY.
&&
.ILM WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
NC...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 6 AM EST EARLY THIS MORNING FOR
AMZ254-256.
SMALL CRAFT ADVISORY UNTIL 10 AM EST THIS MORNING FOR AMZ250-
252.
&&
$$
SYNOPSIS...MJC
NEAR TERM...DRH
SHORT TERM...MJC
LONG TERM...JDW
AVIATION...DCH/MAC
AREA FORECAST DISCUSSION...UPDATED
NWS CORPUS CHRISTI TX
1157 PM CST SAT FEB 21 2015
.DISCUSSION...SWELLS ARE STILL RUNNING VERY HIGH OVER THE GULF
WATERS. AS A RESULT...HAVE EXTENDED THE HIGH RISK OF RIP CURRENTS
THROUGH 6 AM SUNDAY. IF SWELLS REMAIN HIGH (7 TO 8 FEET) WITH
PERIODS 8 TO 9 SECONDS...WILL HAVE TO EXTEND THE RISK THROUGH
SUNDAY.
&&
.PREV DISCUSSION... /ISSUED 1045 PM CST SAT FEB 21 2015/
DISCUSSION...UPDATED FOR 06Z TAFS.
AVIATION...STRATUS/FOG STARTING TO DEVELOP ACROSS VCT AND CRP
TERMINALS. THIS WILL SPREAD TO ALI IN THE NEXT COUPLE OF HOURS.
STILL EXPECT IFR TO LIFR CONDITIONS FOR THESE THREE SITES
OVERNIGHT WITH MVFR CIGS POSSIBLY DEVELOPING FOR LRD AROUND
MORNING. NOT A BIG IMPROVEMENT SUNDAY WITH ALI/CRP/VCT REMAINING
MVFR WITH STRATUS. HAVE FRONT MOVING INTO THE AREA AROUND 03-04Z
SUNDAY NIGHT WITH WIND SHIFT AND LOW CEILINGS EXPECTED ONCE
AGAIN. WILL ALSO INTRODUCE PRECIP CHANCE INTO TAFS FOR SUNDAY
NIGHT.
PREV DISCUSSION... /ISSUED 955 PM CST SAT FEB 21 2015/
DISCUSSION...HAVE DELAYED ONSET OF TONIGHT/S STRATUS ACROSS
WESTERN 2/3 OF THE CWA BY SEVERAL HOURS. 00Z NAM AND LATEST RAP
AND HRRR INDICATE THAT A LLJ OF 20 TO 25 KTS AT 925 SHOULD
DEVELOP AFTER MIDNIGHT WITH STRATUS DEVELOPMENT RAPIDLY INCREASING
NEARLY AREAWIDE AT THAT TIME. ENOUGH MOISTURE ADVECTION WILL
LIKELY LEAD TO SOME FOG DEVELOPMENT ACROSS MARINE AREAS AND
POSSIBLY ACROSS LAND AREAS. LIGHT SHOWERS MAY ALSO DEVELOP WITHIN
LOW LEVEL FLOW ACROSS EASTERN AREAS LATE TONIGHT...WITH BETTER
CHANCES SUNDAY MORNING. ONLY OTHER CHANGE TO INHERITED FORECAST
WERE MINOR EDITS TO HOURLY DEWPOINTS. AN ADDITIONAL UPDATE MAY BE
SENT LATE THIS EVENING REGARDING RIP CURRENT RISK. FOR NOW...HAVE
HIGH RIP CURRENT ADVISORY EXPIRING AT MIDNIGHT...BUT MAY NEED TO
EXTEND THE ADVISORY THROUGH THE REMAINDER OF THE NIGHT.
&&
.PRELIMINARY POINT TEMPS/POPS...
CORPUS CHRISTI 64 76 47 51 39 / 10 20 50 60 40
VICTORIA 64 72 42 44 35 / 10 40 50 60 40
LAREDO 64 82 48 49 40 / 10 10 50 60 30
ALICE 64 81 46 50 38 / 10 20 50 60 40
ROCKPORT 63 73 47 50 40 / 10 20 50 60 40
COTULLA 60 73 43 45 38 / 10 30 50 60 30
KINGSVILLE 64 79 48 52 39 / 10 10 50 60 40
NAVY CORPUS 64 73 49 52 41 / 10 20 50 60 40
&&
.CRP WATCHES/WARNINGS/ADVISORIES...
TX...RIP CURRENT RISK UNTIL 6 AM CST SUNDAY FOR THE FOLLOWING ZONES:
ARANSAS...CALHOUN...KLEBERG...NUECES.
GM...SMALL CRAFT ADVISORY UNTIL 6 AM CST SUNDAY FOR THE FOLLOWING
ZONES: WATERS FROM BAFFIN BAY TO PORT ARANSAS FROM 20 TO 60
NM...WATERS FROM PORT ARANSAS TO MATAGORDA SHIP CHANNEL
FROM 20 TO 60 NM.
&&
$$
GW/86...SHORT TERM
AREA FORECAST DISCUSSION
NWS AUSTIN/SAN ANTONIO TX
1101 PM CST SAT FEB 21 2015
.AVIATION...
A COLD FRONT IS MOVING SLOWLY SOUTHWARD. CIGS HAVE DROPPED TO
MVFR AT THE SAN ANTONIO AIRPORTS AND AUS WILL BE THERE SOON. THEY
WILL DROP TO IFR EARLY MORNING SUNDAY. DRT WILL DROP TO MVFR BY
EARLY MORNING AND IFR BY LATE MORNING. RAIN IS EXPECTED TO BEGIN
LATE MORNING IN AUSTIN AND SAN ANTONIO AND THIS WILL LOWER CIGS TO
LIFR. RAIN IS EXPECTED TO END LATE AFTERNOON AND CIGS WILL IMPROVE
TO IFR. AT THAT TIME WINDS WILL INCREASE FROM THE NORTH WITH SPEED
OF 15 TO 20 KTS AND POSSIBLY HIGHER GUSTS.
&&
.PREV DISCUSSION... /ISSUED 1017 PM CST SAT FEB 21 2015/
UPDATE...DECREASED CLOUD COVER IN THE NEAR SHORT TERM (NEXT 3
HOURS) TO FIT OBSERVATIONAL TRENDS BUT BLENDED IN WITH QUICK CLOUD
COVER RETURN 3AM TO 6AM. INCREASED POPS 3AM-6AM TO 20% FOR FAR
NORTHERN HILL COUNTRY AS ISENTROPIC UPGLIDE INCREASES. UPDATES HAVE
BEEN POSTED AND AN UPDATED DISCUSSION CAN BE FOUND DIRECTLY BELOW.
/ALLEN/
DISCUSSION...A SURFACE PRESSURE TROUGH WEAKNESS SANDWICHED BETWEEN
HIGH PRESSURE CENTERS LOCATED IN THE GULF OF MEXICO AND THE NORTHERN
PLAINS IN AIDING NORTH WINDS ACROSS THE REGION THIS EVENING. THIS
WIND SHIFT WILL BE THE PRECURSOR TO THE STRONGER SECONDARY ARCTIC
FRONT POISED TO MOVE INTO THE REGION TOMORROW AFTERNOON AND EVENING.
TONIGHT WILL BE THE LAST MILD EVENING/MORNING WITH LOWS EXPECTED IN
THE MID TO UPPER 40S NORTH TO MID 50S CENTRAL AND NEAR 60F ALONG THE
COASTAL PLAINS. WEAK H5 DISTURBANCES IN THE ZONAL FLOW WILL COMBINE
WITH INCREASING (ALBEIT WEAK) ISENTROPIC UPGLIDE NEAR DAWN AND THIS
SHOULD LEAD TO AN INCREASE IN LIGHT SHOWER ACTIVITY ACROSS THE
NORTHERN HILL COUNTRY INTO WILLIAMSON/TRAVIS COUNTIES. HAVE INCLUDED
SOME LIGHT SHOWER WORDING ON THIS UPDATE FOR THE 3AM TO 6AM TIME
FRAME. THESE LIFTING FEATURES SHOULD HELP MORE SHOWER ACTIVITY
DEVELOP THROUGH THE MID TO LATE MORNING HOURS FOR AREAS NORTH OF
I-10. INTERESTINGLY...THE HRRR PLACES SLIGHTLY NEGATIVE SHOWALTERS
IN THIS VICINITY THAT MAY ALLOW FOR POCKETS OF MODERATE SHOWERS AND
AN ELEVATED RUMBLE OF THUNDER MAY NOT BE IMPOSSIBLE.
CONCERNING THE WINTER WEATHER POTENTIAL MONDAY INTO TUESDAY...MODELS
HAVE COOLED SLIGHTLY ACROSS THE HILL COUNTRY AND FOR PORTIONS OF THE
I-35 CORRIDOR ON THE 18Z/21Z MODEL RUNS. HOWEVER...PRECIPITATION
AMOUNTS STILL REMAIN A QUESTION AS WEAK LIFTING MECHANISMS WILL BE
IN PLACE. NEW 00Z NAM AND 21Z SREF CONSENSUS STILL PLACES MORE
ORGANIZED PRECIPITATION CORE FARTHER NORTH OF THE REGION. FIRST
PEEKS AT HI-RES DATA ALSO SUGGEST LESS CONSOLIDATED LIGHT
DRIZZLE/SHOWER POCKETS ACROSS THE REGION MONDAY MORNING DURING
POSSIBLE IMPACT WINDOW WHEN TEMPS WILL BE NEAR FREEZING. WILL
CONTINUE TO MONITOR NEW GLOBAL/HI-RES 00Z MODEL DATA TO DETERMINE IF
AND WHERE AN WINTER WEATHER ADVISORY MAY BE WARRANTED FOR PORTIONS
OF THE HILL COUNTRY. /ALLEN/
PREV DISCUSSION... /ISSUED 237 PM CST SAT FEB 21 2015/
SHORT TERM (TONIGHT THROUGH SUNDAY NIGHT)...
CLOUD COVER ONCE AGAIN NEARLY BISECTS THE CWA FROM WEST TO EAST
WITH ABUNDANT LOW-LEVEL MOISTURE CONTINUING ACROSS THE EASTERN
COUNTIES. THE SURFACE LOW WHICH CAUSED THE BREEZY SOUTHERLY FLOW
FOR US YESTERDAY HAS SINCE SHIFTED EAST AND MUCH CALMER WINDS ARE
IN PLACE. THE INITIAL WIND SHIFT ON THE BACKSIDE OF THE SURFACE
LOW IS CURRENTLY BEGINNING TO MOVE THROUGH OUR NORTHERN
ZONES...BUT COOLER TEMPERATURES ARE LAGGING BEHIND. THE ACTUAL
ARCTIC COLD FRONT WE HAVE BEEN ADVERTISING REMAINS WELL NORTH OF
THE REGION AND CAN BE SEEN BY THE SURFACE HIGH BEGINNING TO ENTER
THE CENTRAL PLAINS. AS THE INITIAL WIND SHIFT ENTERS THE EASTERN
ZONES THIS AFTERNOON...THERE COULD BE AN ISOLATED SHOWER...BUT
HIGH-RES MODEL GUIDANCE IS NOT TOO KEEN ON THIS OUTCOME. WILL
KEEP A 20 POP FOR SHOWERS FOR THE EASTERN COUNTIES TO ACCOUNT FOR
ANY STRAY SHOWER ACTIVITY.
THE ACTUAL ARCTIC FRONT IS SCHEDULED TO ARRIVE TO THE AREA
TOMORROW EVENING AND POSSIBLE LIGHT RAIN WILL BEGIN DURING THE
DAY. THE BULK OF THE ACTIVITY WILL GET GOING AFTER THE COLD AIR
ARRIVES WHEN THE BEST OVER RUNNING COMMENCES. 12Z UPPER AIR
ANALYSIS SHOWED THE STRENGTHENING WEST COAST RIDGE AND TROUGH TO
ITS EAST DEEPENING. TEXAS IS THEN PLACED IN 40 TO 50 KNOTS OF FLOW
AT 500 MB. THERE IS ALSO AN EMBEDDED DISTURBANCE EXPECTED TO MOVE
THROUGH THE AREA IN THE SOUTHERN FLOW THAT WILL AID WITH THE
LIFTING FOR UPWARD MOTIONS. FORECAST SOUNDINGS SUNDAY NIGHT SHOW A
WARM NOSE ABOVE THE FRONTAL INVERSION WITH TEMPERATURES ABOVE 11C.
THIS WILL DO A GOOD JOB PREVENTING SLEET FROM FALLING IN OUR
CWA...SO OUR MAIN FOCUS WILL THEN SHIFT TO THE FORECAST FOR
SURFACE TEMPERATURES ACROSS THE AREA. THERE CONTINUES TO BE
DISCREPANCIES WITH SOME OF THE MODEL GUIDANCE DEPENDING ON WHICH
ONE YOU ARE LOOKING AT SO WE WILL TRY TO DISCUSS SOME OF WHAT WE
SEE. THE GFS AND ECMWF REMAIN THE WARM OUTLINES WITH 12Z MONDAY
TEMPERATURES REMAINING ABOVE FREEZING FOR THE ENTIRE AREA. THE
NAM/CANADIAN HAVE THE FREEZING LINE INTO THE NORTHERN HILL COUNTRY
AT THAT TIME AND THE SREF IS EVEN A BIT FARTHER SOUTH. AS YOU CAN
SEE THERE ARE VARYING DIFFERENCES LOOKING AT THE GUIDANCE. DIVING
FURTHER INTO THE GFS WE CAN LOOK AT THE GFS ENSEMBLES. THIS SHOWS
US THAT THE WARMER GFS TEMPS ARE ACTUALLY IN THE UPPER QUADRANT OF
ALL THE MEMBERS AND MANY OF THE GFS ENSEMBLE MEMBERS ARE ABOUT 3
DEGREES COLDER ON AVERAGE. THIS GIVE US MORE CONFIDENCE WITH
GOING WITH THE COLDER CAMP AND THUS OUR TEMPERATURE FORECAST
LEADING UP TO MONDAY MORNING WILL FOLLOW CLOSELY TO THE NAM WHICH
IS A GOOD BALANCE TO THE SREF AND THE CANADIAN. THEREFORE WILL
MENTION FREEZING RAIN IN THE FORECAST AFTER 3AM FOR AREAS NORTH OF
A JUNO TO KERRVILLE TO BURNET LINE. IF THE SREF AND CANADIAN
VERIFY...THIS LINE MAY NEED TO BE SHIFTED A BIT FARTHER SOUTH AND
EAST.
LONG TERM (MONDAY THROUGH SATURDAY)...
AS WE GET INTO MONDAY THERE IS INCREASING CONCERN THAT
TEMPERATURES WILL STAY STEADY OR PERHAPS EVEN FALL A COUPLE OF
DEGREES WITH CONTINUED COLD AIR ADVECTION. FORECAST SOUNDING ALSO
SHOW SOME ROOM FOR A BIT OF EVAPORATIVE COOLING...BUT ONLY A
DEGREE OR TWO. THEREFORE WILL MENTION FREEZING RAIN FOR THE
PREVIOUS AREA THROUGH NOON AND FREEZING RAIN OR RAIN FOR THE MOST
LIKELY AREAS TO REMAIN BELOW FREEZING THROUGH THE AFTERNOON HOURS.
IF TEMPERATURES FALL ABOUT 3 DEGREES DURING THE DAY...AUSTIN COULD
BE CLOSE TO FREEZING AS EARLY AS MONDAY AFTERNOON. THIS IS LOW
PROBABILITY BUT NEEDS CLOSE WATCHING. THE NAM FORECAST SOUNDINGS
DO SHOW THE LAYER UNDERNEATH THE WARM NOSE GETTING TO -6C TO -7C
AND THERE COULD BE SOME SLEET MIXING IN. THINK THE WARM NOSE WILL
BE TOO MUCH TO OVERCOME AND OPTED TO JUST KEEP THE FORECAST SIMPLE
AND MENTION FREEZING RAIN AS THE SOLE WINTER WEATHER TYPE.
TEMPERATURES WILL CONTINUE TO DROP SLOWLY AS WE GET INTO MONDAY
NIGHT...AND THE THREAT AREA FOR FREEZING RAIN COULD EXPAND A BIT
TO THE SOUTH AND EAST. THE MAIN QUESTION THEN CHANGES TO HOW MUCH
PRECIPITATION WILL BE CONTINUING AT THE TIME MORE OF THE AREA IS
BELOW FREEZING. WE TALKED YESTERDAY ABOUT MORE LARGE SCALE FORCING
FOR ASCENT DURING THIS PERIOD BUT MODEL GUIDANCE HAS PUSHED THIS
BACK IN TIME A BIT FURTHER AND THUS THE MAIN IMPETUS FOR
PRECIPITATION DEVELOPMENT WILL BE CONTINUED WEAK ISENTROPIC LIFT
ON TOP OF THE FRONTAL LAYER. THIS LIFT WILL BE BECOMING WEAKER AND
MOST MODEL GUIDANCE SHOWS ONLY A FEW HUNDREDTHS OF AN INCH OF
LIQUID EQUIVALENT WHICH SEEMS REASONABLE. HOWEVER...IF THESE LIGHT
AMOUNTS FALL ON A GROUND WHICH IS NO LONGER WARM ANYMORE THERE
COULD BE MINOR IMPACTS ON ELEVATED SURFACES. IF TEMPERATURES GET
INTO THE UPPER 20S ACROSS THE HILL COUNTRY...THERE COULD BE A BIT
MORE IMPACTS IN THIS REGION. HAVE MENTIONED FREEZING RAIN FOR
AREAS NORTH OF A ROCKSPRINGS TO BOERNE TO GIDDINGS LINE MONDAY
NIGHT AND TUESDAY MORNING. THE ENTIRE AREA SHOULD WARM ABOVE
FREEZING BY LATE TUESDAY MORNING AND REMAIN ABOVE FREEZING THROUGH
WEDNESDAY...ENDING THE THREAT FOR WINTER PRECIPITATION.
TO SUMMARIZE...THE MAIN FOCUS FOR THE NEXT 48 TO 72 HOUR WILL BE
THE TEMPERATURE FORECAST ACROSS THE AREA WHILE THERE IS
PRECIPITATION FALLING. OUR GREATEST CONFIDENCE AREA OF SEEING
FREEZING RAIN WILL BE IN THE NORTHERN HILL COUNTRY AND THIS AGREES
WELL WITH THE LATEST WPC ICE PROBABILITY MAPS. ICE ACCUMULATIONS
SHOULD REMAIN LIGHT GIVEN THE WARM TEMPERATURES TODAY...STRENGTH
OF THE WARM NOSE AND TEMPERATURES BEING MAINLY IN THE 30-32 DEGREE
RANGE. WE WILL CONTINUE TO WATCH TEMPERATURE TRENDS CLOSELY AS ANY
DEVIATIONS COULD LEAD TO ADDITIONAL IMPACTS. RESIDENTS SHOULD
CHECK BACK FOR THE LATEST FORECASTS OVER THE NEXT 24 TO 36 HOURS AS
THINGS CAN CHANGE.
THE BASE OF THE TROUGH AND THE BEST UPPER SUPPORT WILL ARRIVE
ACROSS THE AREA BY TUESDAY NIGHT AND RAIN CHANCES WILL CONTINUE IN
THE FORECAST THROUGH WEDNESDAY AFTERNOON. THE FORECAST CONTINUES
TO HAVE LOW CONFIDENCE REGARDING THE LATE WEEK FRONT. THE 12Z
GFS BRINGS ANOTHER STRONG FRONT INTO THE AREA BY EARLY FRIDAY
WHILE THE ECMWF IS MUCH WEAKER WITH THE FRONT. IF THE GFS VERIFIES
WE WILL HAVE TO WATCH TEMPERATURES CLOSELY ONCE AGAIN...BUT THINGS
ARE LIKELY TO CHANGE OVER THE NEXT SEVERAL DAYS.
HAMPSHIRE
&&
.PRELIMINARY POINT TEMPS/POPS...
AUSTIN CAMP MABRY 50 54 34 37 31 / 20 60 50 70 40
AUSTIN BERGSTROM INTL AIRPORT 51 55 36 38 30 / 20 60 50 70 40
NEW BRAUNFELS MUNI AIRPORT 54 58 37 38 32 / 10 60 50 70 40
BURNET MUNI AIRPORT 46 51 32 34 28 / 20 60 60 70 30
DEL RIO INTL AIRPORT 57 70 39 42 36 / 10 30 50 30 10
GEORGETOWN MUNI AIRPORT 48 52 33 35 29 / 20 60 50 70 30
HONDO MUNI AIRPORT 56 64 39 39 34 / 10 40 60 60 30
SAN MARCOS MUNI AIRPORT 53 57 36 38 31 / 20 60 50 70 40
LA GRANGE - FAYETTE REGIONAL 58 61 38 40 32 / 20 60 50 70 40
SAN ANTONIO INTL AIRPORT 56 61 37 39 33 / 10 50 50 70 40
STINSON MUNI AIRPORT 58 62 39 40 34 / 10 40 50 70 40
&&
.EWX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
MESOSCALE/AVIATION...05
SYNOPTIC/GRIDS...15
PUBLIC SERVICE/DATA COLLECTION...33
AREA FORECAST DISCUSSION
NWS CORPUS CHRISTI TX
1045 PM CST SAT FEB 21 2015
.DISCUSSION...UPDATED FOR 06Z TAFS.
&&
.AVIATION...STRATUS/FOG STARTING TO DEVELOP ACROSS VCT AND CRP
TERMINALS. THIS WILL SPREAD TO ALI IN THE NEXT COUPLE OF HOURS.
STILL EXPECT IFR TO LIFR CONDITIONS FOR THESE THREE SITES
OVERNIGHT WITH MVFR CIGS POSSIBLY DEVELOPING FOR LRD AROUND
MORNING. NOT A BIG IMPROVEMENT SUNDAY WITH ALI/CRP/VCT REMAINING
MVFR WITH STRATUS. HAVE FRONT MOVING INTO THE AREA AROUND 03-04Z
SUNDAY NIGHT WITH WIND SHIFT AND LOW CEILINGS EXPECTED ONCE
AGAIN. WILL ALSO INTRODUCE PRECIP CHANCE INTO TAFS FOR SUNDAY
NIGHT.
&&
.PREV DISCUSSION... /ISSUED 955 PM CST SAT FEB 21 2015/
DISCUSSION...HAVE DELAYED ONSET OF TONIGHT/S STRATUS ACROSS
WESTERN 2/3 OF THE CWA BY SEVERAL HOURS. 00Z NAM AND LATEST RAP
AND HRRR INDICATE THAT A LLJ OF 20 TO 25 KTS AT 925 SHOULD
DEVELOP AFTER MIDNIGHT WITH STRATUS DEVELOPMENT RAPIDLY INCREASING
NEARLY AREAWIDE AT THAT TIME. ENOUGH MOISTURE ADVECTION WILL
LIKELY LEAD TO SOME FOG DEVELOPMENT ACROSS MARINE AREAS AND
POSSIBLY ACROSS LAND AREAS. LIGHT SHOWERS MAY ALSO DEVELOP WITHIN
LOW LEVEL FLOW ACROSS EASTERN AREAS LATE TONIGHT...WITH BETTER
CHANCES SUNDAY MORNING. ONLY OTHER CHANGE TO INHERITED FORECAST
WERE MINOR EDITS TO HOURLY DEWPOINTS. AN ADDITIONAL UPDATE MAY BE
SENT LATE THIS EVENING REGARDING RIP CURRENT RISK. FOR NOW...HAVE
HIGH RIP CURRENT ADVISORY EXPIRING AT MIDNIGHT...BUT MAY NEED TO
EXTEND THE ADVISORY THROUGH THE REMAINDER OF THE NIGHT.
&&
.PRELIMINARY POINT TEMPS/POPS...
CORPUS CHRISTI 64 76 47 51 39 / 10 20 50 60 40
VICTORIA 64 72 42 44 35 / 10 40 50 60 40
LAREDO 64 82 48 49 40 / 10 10 50 60 30
ALICE 64 81 46 50 38 / 10 20 50 60 40
ROCKPORT 63 73 47 50 40 / 10 20 50 60 40
COTULLA 60 73 43 45 38 / 10 30 50 60 30
KINGSVILLE 64 79 48 52 39 / 10 10 50 60 40
NAVY CORPUS 64 73 49 52 41 / 10 20 50 60 40
&&
.CRP WATCHES/WARNINGS/ADVISORIES...
TX...RIP CURRENT RISK UNTIL MIDNIGHT CST TONIGHT FOR THE FOLLOWING
ZONES: ARANSAS...CALHOUN...KLEBERG...NUECES.
GM...SMALL CRAFT ADVISORY UNTIL 6 AM CST SUNDAY FOR THE FOLLOWING
ZONES: WATERS FROM BAFFIN BAY TO PORT ARANSAS FROM 20 TO 60
NM...WATERS FROM PORT ARANSAS TO MATAGORDA SHIP CHANNEL
FROM 20 TO 60 NM.
SMALL CRAFT ADVISORY UNTIL 11 PM CST THIS EVENING FOR THE
FOLLOWING ZONES: COASTAL WATERS FROM BAFFIN BAY TO PORT
ARANSAS OUT 20 NM...COASTAL WATERS FROM PORT ARANSAS TO
MATAGORDA SHIP CHANNEL OUT 20 NM.
&&
$$
PZ/83...AVIATION
AREA FORECAST DISCUSSION...UPDATED
NWS AUSTIN/SAN ANTONIO TX
1017 PM CST SAT FEB 21 2015
.UPDATE...DECREASED CLOUD COVER IN THE NEAR SHORT TERM (NEXT 3
HOURS) TO FIT OBSERVATIONAL TRENDS BUT BLENDED IN WITH QUICK CLOUD
COVER RETURN 3AM TO 6AM. INCREASED POPS 3AM-6AM TO 20% FOR FAR
NORTHERN HILL COUNTRY AS ISENTROPIC UPGLIDE INCREASES. UPDATES HAVE
BEEN POSTED AND AN UPDATED DISCUSSION CAN BE FOUND DIRECTLY BELOW.
/ALLEN/
&&
.DISCUSSION...A SURFACE PRESSURE TROUGH WEAKNESS SANDWICHED BETWEEN
HIGH PRESSURE CENTERS LOCATED IN THE GULF OF MEXICO AND THE NORTHERN
PLAINS IN AIDING NORTH WINDS ACROSS THE REGION THIS EVENING. THIS
WIND SHIFT WILL BE THE PRECURSOR TO THE STRONGER SECONDARY ARCTIC
FRONT POISED TO MOVE INTO THE REGION TOMORROW AFTERNOON AND EVENING.
TONIGHT WILL BE THE LAST MILD EVENING/MORNING WITH LOWS EXPECTED IN
THE MID TO UPPER 40S NORTH TO MID 50S CENTRAL AND NEAR 60F ALONG THE
COASTAL PLAINS. WEAK H5 DISTURBANCES IN THE ZONAL FLOW WILL COMBINE
WITH INCREASING (ALBEIT WEAK) ISENTROPIC UPGLIDE NEAR DAWN AND THIS
SHOULD LEAD TO AN INCREASE IN LIGHT SHOWER ACTIVITY ACROSS THE
NORTHERN HILL COUNTRY INTO WILLIAMSON/TRAVIS COUNTIES. HAVE INCLUDED
SOME LIGHT SHOWER WORDING ON THIS UPDATE FOR THE 3AM TO 6AM TIME
FRAME. THESE LIFTING FEATURES SHOULD HELP MORE SHOWER ACTIVITY
DEVELOP THROUGH THE MID TO LATE MORNING HOURS FOR AREAS NORTH OF
I-10. INTERESTINGLY...THE HRRR PLACES SLIGHTLY NEGATIVE SHOWALTERS
IN THIS VICINITY THAT MAY ALLOW FOR POCKETS OF MODERATE SHOWERS AND
AN ELEVATED RUMBLE OF THUNDER MAY NOT BE IMPOSSIBLE.
CONCERNING THE WINTER WEATHER POTENTIAL MONDAY INTO TUESDAY...MODELS
HAVE COOLED SLIGHTLY ACROSS THE HILL COUNTRY AND FOR PORTIONS OF THE
I-35 CORRIDOR ON THE 18Z/21Z MODEL RUNS. HOWEVER...PRECIPITATION
AMOUNTS STILL REMAIN A QUESTION AS WEAK LIFTING MECHANISMS WILL BE
IN PLACE. NEW 00Z NAM AND 21Z SREF CONSENSUS STILL PLACES MORE
ORGANIZED PRECIPITATION CORE FARTHER NORTH OF THE REGION. FIRST
PEEKS AT HI-RES DATA ALSO SUGGEST LESS CONSOLIDATED LIGHT
DRIZZLE/SHOWER POCKETS ACROSS THE REGION MONDAY MORNING DURING
POSSIBLE IMPACT WINDOW WHEN TEMPS WILL BE NEAR FREEZING. WILL
CONTINUE TO MONITOR NEW GLOBAL/HI-RES 00Z MODEL DATA TO DETERMINE IF
AND WHERE AN WINTER WEATHER ADVISORY MAY BE WARRANTED FOR PORTIONS
OF THE HILL COUNTRY. /ALLEN/
&&
.PREV DISCUSSION... /ISSUED 604 PM CST SAT FEB 21 2015/
AVIATION...
A COLD FRONT IS STALLED ACROSS THE REGION FROM NEAR AUSTIN TO
DRYDEN. FLYING CONDITIONS ARE VFR AT ALL TERMINALS. LOOKING FOR
CIGS TO DROP TO MVFR AROUND MIDNIGHT AT AUSTIN AND SAN ANTONIO.
THEY WILL DROP TO IFR EARLY MORNING SUNDAY. DRT WILL DROP TO MVFR
BY EARLY MORNING AND IFR BY LATE MORNING. RAIN IS EXPECTED TO
BEGIN LATE MORNING IN AUSTIN AND SAN ANTONIO AND THIS WILL LOWER
CIGS TO LIFR.
PREV DISCUSSION... /ISSUED 237 PM CST SAT FEB 21 2015/
SHORT TERM (TONIGHT THROUGH SUNDAY NIGHT)...
CLOUD COVER ONCE AGAIN NEARLY BISECTS THE CWA FROM WEST TO EAST
WITH ABUNDANT LOW-LEVEL MOISTURE CONTINUING ACROSS THE EASTERN
COUNTIES. THE SURFACE LOW WHICH CAUSED THE BREEZY SOUTHERLY FLOW
FOR US YESTERDAY HAS SINCE SHIFTED EAST AND MUCH CALMER WINDS ARE
IN PLACE. THE INITIAL WIND SHIFT ON THE BACKSIDE OF THE SURFACE
LOW IS CURRENTLY BEGINNING TO MOVE THROUGH OUR NORTHERN
ZONES...BUT COOLER TEMPERATURES ARE LAGGING BEHIND. THE ACTUAL
ARCTIC COLD FRONT WE HAVE BEEN ADVERTISING REMAINS WELL NORTH OF
THE REGION AND CAN BE SEEN BY THE SURFACE HIGH BEGINNING TO ENTER
THE CENTRAL PLAINS. AS THE INITIAL WIND SHIFT ENTERS THE EASTERN
ZONES THIS AFTERNOON...THERE COULD BE AN ISOLATED SHOWER...BUT
HIGH-RES MODEL GUIDANCE IS NOT TOO KEEN ON THIS OUTCOME. WILL
KEEP A 20 POP FOR SHOWERS FOR THE EASTERN COUNTIES TO ACCOUNT FOR
ANY STRAY SHOWER ACTIVITY.
THE ACTUAL ARCTIC FRONT IS SCHEDULED TO ARRIVE TO THE AREA
TOMORROW EVENING AND POSSIBLE LIGHT RAIN WILL BEGIN DURING THE
DAY. THE BULK OF THE ACTIVITY WILL GET GOING AFTER THE COLD AIR
ARRIVES WHEN THE BEST OVER RUNNING COMMENCES. 12Z UPPER AIR
ANALYSIS SHOWED THE STRENGTHENING WEST COAST RIDGE AND TROUGH TO
ITS EAST DEEPENING. TEXAS IS THEN PLACED IN 40 TO 50 KNOTS OF FLOW
AT 500 MB. THERE IS ALSO AN EMBEDDED DISTURBANCE EXPECTED TO MOVE
THROUGH THE AREA IN THE SOUTHERN FLOW THAT WILL AID WITH THE
LIFTING FOR UPWARD MOTIONS. FORECAST SOUNDINGS SUNDAY NIGHT SHOW A
WARM NOSE ABOVE THE FRONTAL INVERSION WITH TEMPERATURES ABOVE 11C.
THIS WILL DO A GOOD JOB PREVENTING SLEET FROM FALLING IN OUR
CWA...SO OUR MAIN FOCUS WILL THEN SHIFT TO THE FORECAST FOR
SURFACE TEMPERATURES ACROSS THE AREA. THERE CONTINUES TO BE
DISCREPANCIES WITH SOME OF THE MODEL GUIDANCE DEPENDING ON WHICH
ONE YOU ARE LOOKING AT SO WE WILL TRY TO DISCUSS SOME OF WHAT WE
SEE. THE GFS AND ECMWF REMAIN THE WARM OUTLINES WITH 12Z MONDAY
TEMPERATURES REMAINING ABOVE FREEZING FOR THE ENTIRE AREA. THE
NAM/CANADIAN HAVE THE FREEZING LINE INTO THE NORTHERN HILL COUNTRY
AT THAT TIME AND THE SREF IS EVEN A BIT FARTHER SOUTH. AS YOU CAN
SEE THERE ARE VARYING DIFFERENCES LOOKING AT THE GUIDANCE. DIVING
FURTHER INTO THE GFS WE CAN LOOK AT THE GFS ENSEMBLES. THIS SHOWS
US THAT THE WARMER GFS TEMPS ARE ACTUALLY IN THE UPPER QUADRANT OF
ALL THE MEMBERS AND MANY OF THE GFS ENSEMBLE MEMBERS ARE ABOUT 3
DEGREES COLDER ON AVERAGE. THIS GIVE US MORE CONFIDENCE WITH
GOING WITH THE COLDER CAMP AND THUS OUR TEMPERATURE FORECAST
LEADING UP TO MONDAY MORNING WILL FOLLOW CLOSELY TO THE NAM WHICH
IS A GOOD BALANCE TO THE SREF AND THE CANADIAN. THEREFORE WILL
MENTION FREEZING RAIN IN THE FORECAST AFTER 3AM FOR AREAS NORTH OF
A JUNO TO KERRVILLE TO BURNET LINE. IF THE SREF AND CANADIAN
VERIFY...THIS LINE MAY NEED TO BE SHIFTED A BIT FARTHER SOUTH AND
EAST.
LONG TERM (MONDAY THROUGH SATURDAY)...
AS WE GET INTO MONDAY THERE IS INCREASING CONCERN THAT
TEMPERATURES WILL STAY STEADY OR PERHAPS EVEN FALL A COUPLE OF
DEGREES WITH CONTINUED COLD AIR ADVECTION. FORECAST SOUNDING ALSO
SHOW SOME ROOM FOR A BIT OF EVAPORATIVE COOLING...BUT ONLY A
DEGREE OR TWO. THEREFORE WILL MENTION FREEZING RAIN FOR THE
PREVIOUS AREA THROUGH NOON AND FREEZING RAIN OR RAIN FOR THE MOST
LIKELY AREAS TO REMAIN BELOW FREEZING THROUGH THE AFTERNOON HOURS.
IF TEMPERATURES FALL ABOUT 3 DEGREES DURING THE DAY...AUSTIN COULD
BE CLOSE TO FREEZING AS EARLY AS MONDAY AFTERNOON. THIS IS LOW
PROBABILITY BUT NEEDS CLOSE WATCHING. THE NAM FORECAST SOUNDINGS
DO SHOW THE LAYER UNDERNEATH THE WARM NOSE GETTING TO -6C TO -7C
AND THERE COULD BE SOME SLEET MIXING IN. THINK THE WARM NOSE WILL
BE TOO MUCH TO OVERCOME AND OPTED TO JUST KEEP THE FORECAST SIMPLE
AND MENTION FREEZING RAIN AS THE SOLE WINTER WEATHER TYPE.
TEMPERATURES WILL CONTINUE TO DROP SLOWLY AS WE GET INTO MONDAY
NIGHT...AND THE THREAT AREA FOR FREEZING RAIN COULD EXPAND A BIT
TO THE SOUTH AND EAST. THE MAIN QUESTION THEN CHANGES TO HOW MUCH
PRECIPITATION WILL BE CONTINUING AT THE TIME MORE OF THE AREA IS
BELOW FREEZING. WE TALKED YESTERDAY ABOUT MORE LARGE SCALE FORCING
FOR ASCENT DURING THIS PERIOD BUT MODEL GUIDANCE HAS PUSHED THIS
BACK IN TIME A BIT FURTHER AND THUS THE MAIN IMPETUS FOR
PRECIPITATION DEVELOPMENT WILL BE CONTINUED WEAK ISENTROPIC LIFT
ON TOP OF THE FRONTAL LAYER. THIS LIFT WILL BE BECOMING WEAKER AND
MOST MODEL GUIDANCE SHOWS ONLY A FEW HUNDREDTHS OF AN INCH OF
LIQUID EQUIVALENT WHICH SEEMS REASONABLE. HOWEVER...IF THESE LIGHT
AMOUNTS FALL ON A GROUND WHICH IS NO LONGER WARM ANYMORE THERE
COULD BE MINOR IMPACTS ON ELEVATED SURFACES. IF TEMPERATURES GET
INTO THE UPPER 20S ACROSS THE HILL COUNTRY...THERE COULD BE A BIT
MORE IMPACTS IN THIS REGION. HAVE MENTIONED FREEZING RAIN FOR
AREAS NORTH OF A ROCKSPRINGS TO BOERNE TO GIDDINGS LINE MONDAY
NIGHT AND TUESDAY MORNING. THE ENTIRE AREA SHOULD WARM ABOVE
FREEZING BY LATE TUESDAY MORNING AND REMAIN ABOVE FREEZING THROUGH
WEDNESDAY...ENDING THE THREAT FOR WINTER PRECIPITATION.
TO SUMMARIZE...THE MAIN FOCUS FOR THE NEXT 48 TO 72 HOUR WILL BE
THE TEMPERATURE FORECAST ACROSS THE AREA WHILE THERE IS
PRECIPITATION FALLING. OUR GREATEST CONFIDENCE AREA OF SEEING
FREEZING RAIN WILL BE IN THE NORTHERN HILL COUNTRY AND THIS AGREES
WELL WITH THE LATEST WPC ICE PROBABILITY MAPS. ICE ACCUMULATIONS
SHOULD REMAIN LIGHT GIVEN THE WARM TEMPERATURES TODAY...STRENGTH
OF THE WARM NOSE AND TEMPERATURES BEING MAINLY IN THE 30-32 DEGREE
RANGE. WE WILL CONTINUE TO WATCH TEMPERATURE TRENDS CLOSELY AS ANY
DEVIATIONS COULD LEAD TO ADDITIONAL IMPACTS. RESIDENTS SHOULD
CHECK BACK FOR THE LATEST FORECASTS OVER THE NEXT 24 TO 36 HOURS AS
THINGS CAN CHANGE.
THE BASE OF THE TROUGH AND THE BEST UPPER SUPPORT WILL ARRIVE
ACROSS THE AREA BY TUESDAY NIGHT AND RAIN CHANCES WILL CONTINUE IN
THE FORECAST THROUGH WEDNESDAY AFTERNOON. THE FORECAST CONTINUES
TO HAVE LOW CONFIDENCE REGARDING THE LATE WEEK FRONT. THE 12Z
GFS BRINGS ANOTHER STRONG FRONT INTO THE AREA BY EARLY FRIDAY
WHILE THE ECMWF IS MUCH WEAKER WITH THE FRONT. IF THE GFS VERIFIES
WE WILL HAVE TO WATCH TEMPERATURES CLOSELY ONCE AGAIN...BUT THINGS
ARE LIKELY TO CHANGE OVER THE NEXT SEVERAL DAYS.
HAMPSHIRE
&&
.PRELIMINARY POINT TEMPS/POPS...
AUSTIN CAMP MABRY 52 54 34 37 31 / 20 60 50 70 40
AUSTIN BERGSTROM INTL AIRPORT 53 55 36 38 30 / 20 60 50 70 40
NEW BRAUNFELS MUNI AIRPORT 56 58 37 38 32 / 10 60 50 70 40
BURNET MUNI AIRPORT 48 51 32 34 28 / 20 60 60 70 30
DEL RIO INTL AIRPORT 59 70 39 42 36 / 10 30 50 30 10
GEORGETOWN MUNI AIRPORT 50 52 33 35 29 / 20 60 50 70 30
HONDO MUNI AIRPORT 58 64 39 39 34 / 10 40 60 60 30
SAN MARCOS MUNI AIRPORT 55 57 36 38 31 / 20 60 50 70 40
LA GRANGE - FAYETTE REGIONAL 60 61 38 40 32 / 20 60 50 70 40
SAN ANTONIO INTL AIRPORT 58 61 37 39 33 / 10 50 50 70 40
STINSON MUNI AIRPORT 60 62 39 40 34 / 10 40 50 70 40
&&
.EWX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
MESOSCALE/AVIATION...05
SYNOPTIC/GRIDS...15
PUBLIC SERVICE/DATA COLLECTION...33
AREA FORECAST DISCUSSION
NWS GREEN BAY WI
1044 PM CST SAT FEB 21 2015
UPDATED AVIATION PORTION FOR 06Z TAF ISSUANCE
.SHORT TERM...TONIGHT AND SUNDAY
ISSUED AT 224 PM CST SAT FEB 21 2015
THE LATEST RAP ANALYSIS AND SATELLITE/RADAR IMAGERY SHOW THE NEXT
ARCTIC COLD FRONT DROPPING SOUTHEAST ACROSS NORTH-CENTRAL TO
WEST-CENTRAL WISCONSIN EARLY THIS AFTERNOON. LIGHT AREA OF SNOW
RESIDING WITHIN A WEAK MID-LEVEL FGEN ZONE IS MOVING EAST ACROSS
CENTRAL WISCONSIN...THOUGH SUSPECT SOME OF THAT AREA IS NOT REACHING
THE GROUND. ADDITIONALLY...ALSO SEEING LIGHT RETURNS DEVELOPING
OVER OCONTO AND MARINETTE COUNTIES WHERE WEAK SURFACE CONVERGENCE
HAS DEVELOPED. THIS WILL LIKELY EXPAND LATER THIS AFTERNOON BASED ON
TRENDS AND ACCORDING TO THE HI-RES MODELS. BEHIND THE
FRONT...ARCTIC HIGH PRESSURE IS BUILDING SOUTHEAST INTO THE NORTHERN
PLAINS WHERE TEMPS WERE WELL BELOW ZERO EARLIER THIS MORNING.
FORECAST CONCERNS INCLUDE LIGHT SNOW CHANCES THROUGH THIS
EVENING...BEFORE ATTENTION TURNS TO DANGEROUS WIND CHILLS.
TONIGHT...A SHORTWAVE TROUGH OVER SOUTH-CENTRAL CANADA WILL DRIVE
THE COLD FRONT ACROSS THE REST OF THE REGION THIS EVENING...WHILE A
BEEFY ARCTIC HIGH MOVES INTO THE NORTHERN GREAT PLAINS AND WESTERN
GREAT LAKES. AHEAD OF THE SHORTWAVE...THE HIGHER RES MODELS ARE
DEPICTING A WEAK SURFACE TROUGH DEVELOPING OVER NORTHEAST WISCONSIN
THIS EVENING WHICH COULD PROMOTE LIGHT SNOW DEVELOPMENT. HAVE KEPT
A SMALL CHANCE IN THE FORECAST THROUGH THE EVENING TO ACCOUNT FOR
THIS FEATURE. OTHERWISE...THE INCOMING ARCTIC HIGH WILL PUSH
RESIDUAL MID-LEVEL MOISTURE TO THE EAST WHICH WILL END SNOW CHANCES
BY AROUND MIDNIGHT. TEMPERATURES SHOULD FALL QUICKLY AS SKIES CLEAR
AND ARCTIC AIR POURS ACROSS THE REGION. POTENTIAL IS THERE FOR
DECOUPLING OVER N-C WISCONSIN...BUT THINKING IF WINDS BECOME CALM IT
WILL BE ONLY FOR A BRIEF TIME. THE COMBINATION OF COLD TEMPS AND
THE BRISK NW WINDS SUPPORT THE WIND CHILL ADVISORY CURRENTLY IN
EFFECT SO NO CHANGES TO HEADLINES.
SUNDAY...COLD ADVECTION WILL CONTINUE INTO SUNDAY MORNING AND TEMPS
COULD CONTINUE THEIR FALL INTO MID-MORNING DESPITE AMPLE SUNSHINE.
THE PRESSURE GRADIENT WILL SLACKEN A BIT THROUGH THE DAY AS THE
CENTER OF THE HIGH DRIFTS CLOSER TO THE REGION...BUT PROJECTED WIND
CHILLS WILL ONLY WARM TO AROUND 15 TO 22 BELOW THROUGH THE
AFTERNOON. THIS IS CLOSE ENOUGH TO LEAVE THE ENDING TIME OF THE
ADVISORY ALONE. HIGHS WILL ONLY WARM INTO THE -5 TO 0 RANGE NORTH
TO THE 5 TO 10 ABOVE RANGE SOUTH.
.LONG TERM...SUNDAY NIGHT THROUGH SATURDAY
ISSUED AT 224 PM CST SAT FEB 21 2015
A LOOK AT THE RECENT BEHAVIOR OF THE 500 MB PATTERN FITS IN WELL
WITH OUR TEMPERATURES THIS MONTH. A WESTERN RIDGE AND EASTERN
TROUGH ARE QUITE PERSISTENT...SHOWING CHANGES MORE IN AMPLITUDE
THAN POSITION. WITH THAT...OUR TEMPERATURES HAVE SPENT TIME
VARYING BETWEEN BELOW NORMAL AND WAY BELOW NORMAL. FOR THE TIME
BEING...THIS TREND LOOKS TO CONTINUE.
SUNDAY NIGHT INTO MONDAY MORNING SHOWS TEMPERATURES BOTTOMING OUT
NEARLY AS LOW AS THEY HAVE GOTTEN THIS WINTER. FORECASTING WIND
CHILLS WILL BE DIFFICULT ACROSS THE NORTH. CALM WINDS WILL HELP
TEMPERATURES FALL TO THEIR COLDEST POSSIBLE LEVELS...BUT CALM
CONDITIONS COULD PRECLUDE A WARNING BY NOT MEETING THE WIND
THRESHOLD. MORE WIND WILL HELP PUSH WIND CHILLS DOWN...BUT WOULD
BE LIMITING BY ARRESTING TEMPERATURE FALLS. GIVEN THE
UNCERTAINTY...WILL LET LATER SHIFTS MAKE THE FINAL DECISION ON
ANYTHING TO BE ISSUED FOR WIND CHILL. AN ADVISORY FOR MOST OR ALL
OF THE AREA IS PLAUSIBLE...AND A WARNING IN NORTH CENTRAL
WISCONSIN MAY BE ON THE TABLE. THOUGH THERE MIGHT BE A LACK OF
CONFIDENCE IN THE PRECISE HEADLINES...CONFIDENCE IS QUITE HIGH
THAT IT WILL BE VERY COLD AND THOSE GOING TO WORK AND SCHOOL
MONDAY MORNING SHOULD PREPARE ACCORDINGLY.
INCREASING SOUTHWEST WINDS ON MONDAY CAN BE EXPECTED...ESPECIALLY
LATE IN THE AFTERNOON AND EVENING HOURS. THESE WINDS WILL HELP
BOOST TEMPERATURES LATE MONDAY INTO TUESDAY. WITH ANOTHER IN THE
PARADE OF LOWS SLIDING BY TO OUR NORTHEAST BRINGING AN ARCTIC
FRONT TO OUR AREA...WE WILL HAVE ANOTHER CHANCE FOR SNOW SHOWERS.
GUIDANCE REMAINS FRUSTRATINGLY ON THE EDGE BETWEEN BRINGING SOME
LIGHT SNOW WELL INTO THE AREA...OR ONLY BRINGING A GLANCING BLOW
TO THE NORTH AND EAST. ULTIMATELY THIS FORECAST DOES NOT MAKE
SIGNIFICANT CHANGES...THE EQUIVALENT OF DUMPING THE PUCK INTO THE
CORNER AND HOPING THAT A LINE CHANGE OF MODELS WILL BRING MORE
CLARITY.
BITTER COLD RETURNS FOR WEDNESDAY AND THURSDAY BUT WITH SOME HOPE FOR
A SLIGHT BUMP UP TO MERELY BELOW NORMAL TEMPERATURES LATE IN THE WEEK.
&&
.AVIATION...FOR 06Z TAF ISSUANCE
ISSUED AT 1044 PM CST SAT FEB 21 2015
STUBBORN AREA OF LIGHT SNOW/FLURRIES CONTS TO HANG AROUND FAR ERN
WI LATE THIS EVENING ASSOCIATED WITH WEAK CONVERGENCE ALONG A SFC
TROF. THIS ACTIVITY SHOULD CONT TO SAG S-SE AND MOVE OUT OF
E-CNTRL WI DURING THE EARLY MORNING HOURS. VSBYS WL BE REDUCED TO
MVFR CONDITIONS UNDER THE LIGHT SNOW...OTHERWISE VFR CONDITIONS TO
PREVAIL FOR THE REMAINDER OF THE AREA AS DRIER AIR HAS BEGUN TO
ADVECT INTO WI FROM CANADIAN HI PRES OVER THE NRN PLAINS. THESE
VFR CONDITIONS TO THEN PERSIST SUNDAY INTO SUNDAY NGT AS THE HI
PRES GRADUALLY APPROACHES FROM THE WEST. THERE COULD BE SOME GUSTY
NW WINDS ON SUNDAY AS CAA POURS INTO WI.
&&
.GRB WATCHES/WARNINGS/ADVISORIES...
WIND CHILL ADVISORY FROM 3 AM TO 11 AM CST SUNDAY FOR WIZ005-
010>012-018-019-030-035-036.
&&
$$
SHORT TERM.....MPC
LONG TERM......LUCHS
AVIATION.......AK
AREA FORECAST DISCUSSION
NWS RENO NV
258 AM PST SUN FEB 22 2015
.SYNOPSIS...
A STRONG FRONT WILL MOVE THROUGH THE REGION EARLY THIS MORNING
WITH MUCH COLDER TEMPERATURES TODAY AND MONDAY. THERE WILL BE A
PERIOD OF LIGHT SNOW TODAY INTO MONDAY IN THE SIERRA SOUTH OF
HIGHWAY 50, WITH A CHANCE OF SHOWERS ELSEWHERE SOUTH OF HIGHWAY
50. AREAS OF BLOWING DUST MAY OCCUR NORTH OF HIGHWAY 50 AS WINDS
BECOME BREEZY. TEMPERATURES WILL REBOUND TO AROUND AVERAGE BY THE
MIDDLE OF NEXT WEEK WITH NO PRECIPITATION TUESDAY THROUGH
THURSDAY.
&&
.SHORT TERM...
WINDS ARE INCREASING OUT OF THE NORTH AS A STRONG COLD FRONT DROPS
INTO CENTRAL AND SOUTHERN NEVADA THIS MORNING. THERE HAVE BEEN
SOME ISOLATED REPORTS OF SOME SNOW FLURRIES MAINLY IN UPSLOPE
LOCATIONS AROUND LAKE TAHOE. EXPECT VERY ISOLATED SNOW SHOWERS TO
CONTINUE AROUND LAKE TAHOE BEFORE FORCING SHIFTS SOUTH BY MID
MORNING.
SOME MODERATE CHANGES WERE MADE TO THE PREVIOUS FORECAST MAINLY
CONCERNING WINDS AND THE POTENTIAL FOR BLOWING DUST. GENERALLY
INCREASED SUSTAINED WIND SPEEDS TO AROUND 20 MPH FOR LOCATIONS
AROUND AND NORTH OF INTERSTATE 80 INCLUDING THE RENO METRO AREA.
ALSO INCREASED GUSTS MARGINALLY TO AROUND 35 MPH IN THE RENO METRO
AREA AND TO AROUND 40 MPH FOR CHURCHILL AND PERSHING COUNTIES.
CONSIDERING THE AMOUNT OF DUST LOFTED SATURDAY, HAVE ADDED AREAS
OF BLOWING DUST FOR MUCH OF THE FORECAST REGION. THIS INCLUDES
LOCATIONS FROM NORTHERN WASHOE COUNTY THROUGH THE SUSANVILLE AND
RENO METRO AREAS CONTINUING SOUTH AND EAST THROUGH CHURCHILL,
PERSHING, AND MINERAL COUNTIES. FALLON AND OTHER LOCATIONS
DOWNWIND OF DRY LAKE BEDS CAN EXPECT PERIODS OF VISIBILITY
RESTRICTIONS DOWN TO 1 MILE WITH THE POTENTIAL FOR LOCAL
RESTRICTIONS TO LESS THAN 1 MILE BRIEFLY. RENO AND SPANISH SPRINGS
WILL LIKELY SEE BLOWING DUST OUT OF THE SMOKE CREEK DESERT. THERE
COULD BE VISIBILITY RESTRICTIONS DOWN TO 3 MILES AND LOCALLY TO 1
MILE AT TIMES. WINDS FALL OFF BY MONDAY MORNING AND DUST SHOULD
SETTLE QUICKLY.
OTHERWISE, NO OTHER MAJOR CHANGES. STILL EXPECT THE BEST
PRECIPITATION CHANCES PRIMARILY SOUTH OF HIGHWAY 50 IN THE SIERRA
THIS AFTERNOON SPREADING EASTWARD INTO SOUTHERN LYON AND MINERAL
COUNTIES BY LATE THIS EVENING. IN GENERAL, LOCATIONS IN MONO
COUNTY COULD SEE UP TO 2 INCHES WITH 2 TO 4 INCHES ABOVE 7000
FEET. LOCAL TOTALS IN UPSLOPE AREAS COULD SEE ANOTHER INCH OR SO.
ADDITIONALLY, THERE ARE SOME INDICATIONS THAT LEE VINING AND
NEARBY HIGHWAY 395 COULD SEE SOME MORE SNOW ACCUMULATION DUE TO LAKE
ENHANCEMENT OFF OF MONO LAKE. THE HRRR MODEL DOES SHOW A PLUME OF
SNOW DEVELOPING JUST EAST OF LEE VINING ALONG HIGHWAY 395 AND THE
LONG VALLEY CRATER RIM. RESIDENTS AND TRAVELERS SHOULD ANTICIPATE
PERIODS OF INCREASED PRECIPITATION RATES IN THE VICINITY OF MONO
LAKE.
PRECIPITATION EXITS THE FORECAST AREA AS LOW PRESSURE DROPS
FARTHER SOUTH INTO SOUTHERN NEVADA MONDAY AFTERNOON INTO TUESDAY.
SOME LINGERING VERY ISOLATED SNOW SHOWERS WILL BE POSSIBLE OVER
THE HIGHER TERRAIN IN MONO COUNTY, BUT WILL TAPER QUICKLY MONDAY
EVENING AS HIGH PRESSURE AND VERY DRY AIR MOVE IN TUESDAY. BOYD
LONG TERM...WEDNESDAY THROUGH SATURDAY...
RIDGE OF HIGH PRESSURE WILL RETROGRADE WESTWARD TO NEAR 140W,
KEEPING NORTHWEST FLOW OVER THE WESTERN STATES. A WEAK SHORTWAVE
WILL DROP THROUGH THE GREAT BASIN ON WEDNESDAY, WHICH WILL MAINLY
SERVE TO HOLD TEMPERATURES CLOSE TO NORMAL. DRY AND COOL NORTHWEST
FLOW WILL REMAIN OVER THE REGION INTO FRIDAY.
MODELS ARE STILL FLIP-FLOPPING IN THE EXTENDED FORECAST PERIOD,
SHOWING QUITE A DIFFERENT SOLUTION FOR NEXT WEEKEND THAN YESTERDAY.
LATEST 00Z RUNS OF THE ECMWF AND GFS ARE ACTUALLY SHOWING BETTER
PRECIP CHANCES FOR THE SIERRA FRIDAY AND SATURDAY, ALTHOUGH NOT A
BIG STORM BY ANY MEANS. PREVIOUS MODELS HAD SHOWN THESE WAVES AS DRY
INSIDE SLIDERS, BUT THESE LATEST RUNS SEEM TO BE EDGING THE RIDGE
FURTHER WEST TO AROUND 145W, WHICH WILL ALLOW THE SHORTWAVE DROPPING
ALONG THE WEST COAST TO BE ABLE TO PICK UP SOME MOISTURE OFF THE
PACIFIC BEFORE THEY MOVE INTO THE SIERRA.
THIS SYSTEM DOES LOOK PRETTY COLD, WITH SNOW LEVELS AT OR NEAR
VALLEY FLOORS IN WESTERN NEVADA. FORECAST CONFIDENCE ON THE COLDER
TEMPERATURES NEXT WEEKEND IS MEDIUM, BUT OVERALL CONFIDENCE IN
PRECIP AMOUNTS REMAINS LOW AS THIS RELIES HEAVILY ON THE TRACK OF
THE LOW. HOON
&&
.AVIATION...
GENERALLY VFR CONDITIONS EXPECTED FOR KTRK, KTVL, KRNO, KCXP FOR
TODAY WITH KMMH THE ONLY TERMINAL TO SEE POTENTIAL FOR ACCUMULATING
SNOWFALL. COULD SEE -SHSN FOR KMMH AS EARLY AS 15Z SUN WITH THE BEST
CHANCES FROM 21Z SUN TO 12Z MON MORNING. IT`S POSSIBLE TO SEE 1-4
INCHES AT KMMH TONIGHT THROUGH MONDAY MORNING.
BREEZY NORTHEAST SURFACE WINDS ARE EXPECTED TODAY WITH GUSTS AROUND
35 KTS. GUSTY WINDS MAY PRODUCE BLOWING DUST WITH LIMITS TO
VISIBILITY AT TIMES AROUND KRNO, KCXP, KNFL AND KLOL. AREAS OF
MOUNTAIN OBSCURATION IN THE SIERRA EXPECTED THROUGH MONDAY MORNING.
FUENTES
&&
.REV WATCHES/WARNINGS/ADVISORIES...
NV...LAKE WIND ADVISORY FROM 6 AM THIS MORNING TO 6 PM PST THIS
EVENING FOR PYRAMID LAKE IN NVZ004.
LAKE WIND ADVISORY UNTIL 6 PM PST THIS EVENING FOR LAKE TAHOE IN
NVZ002.
CA...LAKE WIND ADVISORY UNTIL 6 PM PST THIS EVENING FOR LAKE TAHOE IN
CAZ072.
&&
$$
FOR MORE INFORMATION FROM THE NATIONAL WEATHER SERVICE VISIT...
HTTP://WEATHER.GOV/RENO (ALL LOWER CASE)
AREA FORECAST DISCUSSION
NWS MOUNT HOLLY NJ
926 AM EST SUN FEB 22 2015
.SYNOPSIS...
A COLD FRONT OVER THE OHIO VALLEY EARLY THIS MORNING WILL MOVE
THROUGH THE AREA TODAY. ARCTIC HIGH PRESSURE OVER THE CENTRAL UNITED
STATES WILL BUILD EASTWARD INTO THE MID-ATLANTIC REGION MONDAY. THE
HIGH WILL SHIFT OFFSHORE AS A CLIPPER LOW TRACKS NORTH OF OUR AREA.
THIS SYSTEM WILL PUSH A COLD FRONT THROUGH OUR AREA WEDNESDAY. HIGH
PRESSURE RETURNS LATE IN THE WEEK.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
WE HAVE ALLOWED THE WARNINGS TO EXPIRE AND REPLACE THEM WITH
SPS(S). NEAR NEAR TERM WE HAVE ADDED SOME PATCHY FOG IN THE SERN
TWO THIRDS OF OUR CWA. NOT A GREAT PUSH, BUT SLIGHTLY DRIER AIR
WILL BE MOVING INTO OUR AREA AS THE DAY PROGRESSES.
AS MUCH AS ONE CAN WITHOUT HURTING ONESELF, TODAY IS THE DAY TO
CLEAR AS MUCH OF THE ICE, SLUSH OFF OF SIDEWALKS, DRIVEWAYS,
STREETS AS WELL AS OPENING CATCH BASINS BECAUSE ANY LEFTOVER WATER
OR SLUSH WILL FREEZE SOLID TONIGHT.
NO OTHER BIG CHANGES WITH THIS UPDATE, MID SHIFT IDEAS ABOUT THE
REST OF TODAY MAINTAINED.
BY MID TO LATE MORNING, IMPROVEMENT IS ANTICIPATED FOR THE ENTIRE
FORECAST AREA, AS THE HRRR SHOWS ANY REMAINING LIGHT PRECIP MOVING
EAST AND OFFSHORE, WITH TEMPERATURES INTO AT LEAST THE MID 30S FOR
MOST LOCATIONS. SOME CLOUDINESS WILL LINGER INTO THE AFTERNOON,
AND WITH THIS IN MIND, AS WELL AS CONSIDERING THE REMAINING
SNOWPACK ACROSS THE REGION, WE UNDERCUT MET/MAV GUIDANCE BY A
COUPLE OF DEGREES ACROSS THE FORECAST AREA WITH REGARD TO MAXIMUM
TEMPERATURES. WE ANTICIPATE HIGHS TO MAINLY BE IN THE MIDDLE TO
UPPER 30S FOR THE FORECAST AREA, EXCEPT SOME LOWER 40S ACROSS
SOUTHERN NJ AND INTO THE DELMARVA, WITH COLDER UPPER 20S/LOWER 30S
REMAINING INTO THE POCONOS.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 AM MONDAY/...
AS THE PREVIOUSLY MENTIONED LOW PRESSURE SYSTEM EXITS FARTHER
OFFSHORE THROUGH TONIGHT, A NEW PUSH OF COLDER, DRIER AIR WILL BE
FELT ACROSS THE REGION ON NORTHWEST BREEZES IN THE WAKE OF THE
DEPARTING LOW PRESSURE AND COLD FRONT. IN ADDITION, A MID-LEVEL
TROUGH WILL BE SETTLING ACROSS THE NORTHEAST TO MID ATLANTIC STATES
AS ARCTIC HIGH PRESSURE GRADUALLY BUILDS EAST FROM THE PLAINS AND
MIDWEST. OVERALL, DRY CONDITIONS ARE EXPECTED THROUGH THE NIGHTTIME
HOURS, SAVE PERHAPS A FEW ISOLATED/SCATTERED SNOW SHOWERS IN THE
POCONOS ON THE NORTHWEST FLOW. WE MOSTLY TOOK A MET/MAV GUIDANCE
BLEND WITH CONTINUITY FOR MINIMUM TEMPS, AND WE EXPECT SOME SINGLE
DIGIT LOW TEMPERATURES IN THE FAR NORTHWEST TO MAINLY TEENS AND
LOWER 20S ELSEWHERE.
&&
.LONG TERM /MONDAY THROUGH SATURDAY/...
A STRONG 1047 MB SURFACE HIGH OVER THE MIDWEST WILL BUILD EASTWARD
INTO THE MID ATLANTIC AND NORTHEAST STATES ON MONDAY. STEADY
PRESSURE RISES FROM THIS PATTERN BE ACCOMPANIED BY A BRISK NW WINDS
THAT USHERS IN THE NEXT SHOT OF COLD ARCTIC AIR. FORECAST MAX TEMPS
GENERALLY IN THE TEENS NORTH AND WEST OF THE FALL LINE AND LOW TO
MID 20S TO THE SOUTH AND EAST. THE HIGHS SHOULD OCCUR IN THE MORNING
AS TEMPS GRADUALLY FALL THROUGHOUT THE DAY OWING TO THE STRONG CAA.
WIND CHILLS AOB ZERO ARE EXPECTED FOR NE PA AND NW NJ AND SINGLE
DIGITS ELSEWHERE. WIND CHILL ADVISORIES WILL LIKELY BE NEEDED FOR
THE POCONOS WITH WIND CHILL VALUES DIPPING BETWEEN 15 AND 20 BELOW
ZERO.
THE CENTER OF THE ARCTIC HIGH IS FORECAST TO SHIFT TOWARD THE
CENTRAL APPALACHIANS MONDAY EVENING AND MID-ATLANTIC COAST EARLY
TUESDAY MORNING. THE PRESSURE GRADIENT WILL RELAX WHICH WILL ALLOW
THE WINDS TO BECOME LIGHT, ESPECIALLY OVERNIGHT. WENT WITH THE
COLDER MOS GUIDANCE FOR LOW TEMPS, IF NOT COLDER IN SPOTS WITH A
EXTENSIVE SNOW COVER. A SIMILAR SETUP OCCURRED YESTERDAY- RECORD LOW
TEMPS WERE SET AND GUIDANCE BIASED WAY TOO WARM. IN THE MONDAY NIGHT
PATTERN, THE CENTER OF THE RIDGE AXIS MOVES OVERHEAD ABOUT 6 HOURS
LATER INTO THE NIGHT COMPARED TO THIS PAST FRIDAY MORNING SO TEMPS
MAY NOT FREE FALL QUITE AS MUCH. WE WILL ALSO LOSE THAT WIND CHILL
FACTOR OVERNIGHT, SO ANY WIND CHILL ADVISORIES FOR THE POCONOS WOULD
NOT BE NECESSARY.
HIGH PRESSURE MOVES OFF THE COAST TUESDAY. SWLY RETURN FLOW AROUND
THE HIGH AND AHEAD OF A CLIPPER SYSTEM TRACKING NORTH OF THE GREAT
LAKES WILL HELP MODERATE THIS ARCTIC AIRMASS A BIT DURING THE
MIDWEEK. TEMPS STILL 15-20F BELOW NORMAL ON TUESDAY AND 5-10F BELOW
ON WEDNESDAY. A COLD FRONT ASSOCIATED WITH THIS CLIPPER WILL MOVE
THRU THE AREA ON WEDNESDAY. THE BEST CHANCE FOR SNOW SHOWERS APPEAR
TO BE AHEAD OF THE FRONT TUESDAY NIGHT AND ESPECIALLY NORTH OF I-78.
ACCUMULATIONS SHOULD BE LIGHT WITH UP TO AN INCH POSSIBLE IN THE
POCONOS.
ON WEDNESDAY NIGHT INTO THURSDAY, AN AREA OF LOW PRESSURE IS
FORECAST TO DEVELOP ALONG THE AFOREMENTIONED FRONTAL BOUNDARY TO
OUR SOUTH. ANY ASSOCIATED PRECIPITATION IS EXPECTED TO REMAIN
MOSTLY TO OUR SOUTH, BUT THERE IS A SLIGHT CHANCE THAT SOME SNOW
MAY MAKE ITS WAY INTO OUR FAR SOUTHERN AND SOUTHEASTERN AREAS. SO
WE WILL KEEP A SLIGHT CHANCE OF SNOW.
COLD TEMPERATURES RETURN BEHIND THIS FRONTAL BOUNDARY FOR THE END
OF THE WEEK. ESPECIALLY AS HIGH PRESSURE MOVES INTO THE AREA
THURSDAY NIGHT INTO FRIDAY. LOWS THURSDAY NIGHT WILL LIKELY GET
INTO THE SINGLE DIGITS TO BELOW ZERO AGAIN. ANOTHER PERIOD OF
SINGLE DIGIT TO BELOW ZERO WIND CHILLS IS EXPECTED WEDNESDAY NIGHT
THROUGH FRIDAY MORNING.
&&
.AVIATION /15Z SUNDAY THROUGH THURSDAY/...
THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG,
KILG, KMIV, KACY AND SURROUNDING AREAS.
REST OF SUNDAY...WHILE PRECIPITATION ENDS EARLY, THE LOWER
CIGS/VSBYS, MAINLY IN THE IFR RANGE, ARE EXPECTED TO REMAIN
THROUGH AT LEAST THE MORNING. WHEN EXACTLY THE LOWER CONDITIONS
WILL BREAK WITH A RETURN TO VFR IS A TRICKY FORECAST AT THIS TIME,
AND THERE ARE DIFFERENCES IN THE GUIDANCE WITH RESPECT TO THIS
OCCURRENCE. FOR NOW, WE HAVE KEPT AN IMPROVEMENT TO VFR BETWEEN
AROUND 16Z TO 18Z, BUT THIS IS A LOW CONFIDENCE FORECAST AS THE
NOTICEABLE PUSH OF COLD, DRY AIR INTO THE REGION DOES NOT OCCUR
UNTIL SUNDAY EVENING/NIGHT. WINDS THROUGH THE DAYTIME SUNDAY ARE
EXPECTED TO BECOME MORE WESTERLY AND THEN NORTHWESTERLY, REMAINING
MOSTLY IN THE 4 TO 8 KNOT RANGE.
OUTLOOK...
MONDAY...BREEZY NW WINDS 10-15 KT WILL GUST TO AROUND 25 KT.
GENERALLY VFR ALTHOUGH CAA STRATOCU MAY TRY TO SNEAK INTO ABE/RDG,
WHICH COULD YIELD MVFR CIGS. CONFIDENCE LOW TO MODERATE ON THIS
HAPPENING.
MONDAY NIGHT THROUGH TUESDAY...VFR AND LIGHT WINDS.
TUESDAY NIGHT AND WEDNESDAY MORNING...MAINLY VFR BUT LOCALIZED/
TEMPORARY RESTRICTIONS POSSIBLE IN SCT SNOW SHOWERS. BEST CHANCE TO
SEE ANY SNOW IS ABE.
WEDNESDAY AFTERNOON THROUGH THURSDAY...VFR. BREEZY NW WINDS RETURN.
&&
.MARINE...
**SINCE MUCH OF DELAWARE BAY IS COVERED BY ICE WE WILL CONTINUE
TO ADD THE PHRASING "ON ICE FREE WATERS" FOR THE FIRST FOUR
PERIODS OF THE FORECAST**
WHILE LIGHTER WINDS BELOW 20 KNOTS ARE EXPECTED FOR OUR AREA WATERS
THROUGH TODAY, SEAS ON THE COASTAL WATERS SHOULD REMAIN AROUND 5
FEET OR SO, ESPECIALLY FOR THE OUTER WATERS AWAY FROM THE NEAR
SHORE. WE THEREFORE CONTINUE THE SMALL CRAFT ADVISORY FOR OUR
COASTAL WATERS THROUGH TODAY, ALTHOUGH CONDITIONS COULD BRIEFLY FALL
BELOW CRITERIA FOR A TIME. LATER TONIGHT, NORTHWESTERLY WINDS WILL
INCREASE, WITH GUSTS REACHING AROUND 25 KNOTS. SEAS MAY ALSO
INCREASE SOME IN RESPONSE. THE SCA WILL CONTINUE FOR THE COASTAL
WATERS THROUGH TONIGHT AND INTO MONDAY.
FOR THE DELAWARE BAY, BOTH SEAS AND WINDS ARE EXPECTED TO REMAIN AT
SUB-ADVISORY LEVELS THROUGH TODAY AND TONIGHT, WITH CONDITIONS THEN
MEETING SCA CRITERIA INTO MONDAY AS NORTHWESTERLY WINDS INCREASE.
OUTLOOK...
MONDAY AND MONDAY NIGHT...SCA ISSUED FOR BOTH THE DE BAY AND COASTAL
ZONES WITH NW GUSTS TO AROUND 25 KT. WINDS RELAX MONDAY NIGHT BUT
SCA LEVEL WINDS MAY LINGER INTO THE EARLY EVENING.
TUESDAY THROUGH WEDNESDAY...SW WINDS AND SEAS WILL APPROACH SCA
LEVELS LATE TUESDAY NIGHT INTO WEDNESDAY MORNING BUT WILL LIKELY
BE JUST BELOW.
WEDNESDAY NIGHT AND THURSDAY...BETTER CHANCE AT SCA CONDITIONS
IN NW FLOW PATTERN.
&&
.PHI WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NJ...NONE.
DE...NONE.
MD...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 6 PM EST MONDAY FOR ANZ450>455.
SMALL CRAFT ADVISORY FROM 6 AM TO 6 PM EST MONDAY FOR ANZ430-
431.
&&
$$
SYNOPSIS...KLEIN
NEAR TERM...GIGI/KLINE/ROBERTSON
SHORT TERM...KLINE
LONG TERM...KLEIN/ROBERTSON
AVIATION...KLEIN/KLINE
MARINE...KLEIN/KLINE
CLIMATE...
AREA FORECAST DISCUSSION
NWS MOUNT HOLLY NJ
509 AM EST SUN FEB 22 2015
.SYNOPSIS...
A COLD FRONT OVER THE OHIO VALLEY EARLY THIS MORNING WILL MOVE
THROUGH THE AREA TODAY. ARCTIC HIGH PRESSURE OVER THE CENTRAL UNITED
STATES WILL BUILD EASTWARD INTO THE MID-ATLANTIC REGION MONDAY. THE
HIGH WILL SHIFT OFFSHORE AS A CLIPPER LOW TRACKS NORTH OF OUR AREA.
THIS SYSTEM WILL PUSH A COLD FRONT THROUGH OUR AREA WEDNESDAY. HIGH
PRESSURE RETURNS LATE IN THE WEEK.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
SOME LEFTOVER ONGOING PRECIP EARLY TODAY AS LOW PRESSURE PROGRESSES
NORTHEASTWARD, WITH ITS ASSOCIATED FRONTS CROSSING OUR REGION.
WINTER WEATHER ADVISORY AND WARNING HEADLINE PRODUCTS WILL CONTINUE
THROUGH EARLY MORNING, AS SOME LIGHT FROZEN PRECIP CONTINUES,
ESPECIALLY ACROSS PORTIONS OF EASTERN PA AND INTO NORTHERN NJ. WHILE
MAINLY LIGHT SNOW CONTINUES THROUGH NORTHERN NJ, THE POCONOS, AND
INTO THE LEHIGH VALLEY, PRECIPITATION IS PRIMARILY FALLING AS
FREEZING RAIN FARTHER SOUTH INTO THE REMAINDER OF SOUTHEASTERN PA,
INCLUDING THE WESTERN PHL METRO SUBURBS, WHERE A WARM LAYER EXISTS
ABOVE THE SUB-FREEZING SURFACE AIR. IN ADDITION, WE HAVE RECEIVED
REPORTS OF SOME ICING INTO SOUTHERN PARTS OF NJ, WHERE PRECIPITATION
IS FALLING PRIMARILY AS RAIN, BUT THE GROUND REMAINS FROZEN.
WE THEREFORE HAVE DECIDED TO RAISE A FREEZING RAIN ADVISORY THROUGH
14Z FOR PORTIONS OF SOUTHERN NJ AND INTO THE CENTRAL DELMARVA WHERE
SURFACE AIR TEMPERATURES REMAIN CLOSE TO FREEZING AND LIGHT PRECIP
IS FALLING. THE STILL FROZEN GROUND WILL LIKELY YIELD SOME LIGHT
ICING ACROSS THESE AREAS AS LIGHT RAIN CONTINUES FOR A FEW MORE
HOURS. IN ADDITION, WE HAVE EXTENDED PORTIONS OF THE WINTER STORM
WARNING THROUGH 14Z ACROSS NORTHERN DELAWARE, THE PHL METRO AREA,
AND CENTRAL NEW JERSEY AS SOME LIGHT RAIN WILL CONTINUE TO FALL OVER
STILL FROZEN GROUND.
BY MID TO LATE MORNING, IMPROVEMENT IS ANTICIPATED FOR THE ENTIRE
FORECAST AREA, AS THE HRRR SHOWS ANY REMAINING LIGHT PRECIP MOVING
EAST AND OFFSHORE, WITH TEMPERATURES INTO AT LEAST THE MID 30S FOR
MOST LOCATIONS. SOME CLOUDINESS WILL LINGER INTO THE AFTERNOON, AND
WITH THIS IN MIND, AS WELL AS CONSIDERING THE REMAINING SNOWPACK
ACROSS THE REGION, WE UNDERCUT MET/MAV GUIDANCE BY A COUPLE OF
DEGREES ACROSS THE FORECAST AREA WITH REGARD TO MAXIMUM
TEMPERATURES. WE ANTICIPATE HIGHS TO MAINLY BE IN THE MIDDLE TO
UPPER 30S FOR THE FORECAST AREA, EXCEPT SOME LOWER 40S ACROSS
SOUTHERN NJ AND INTO THE DELMARVA, WITH COLDER UPPER 20S/LOWER 30S
REMAINING INTO THE POCONOS.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 AM MONDAY/...
AS THE PREVIOUSLY MENTIONED LOW PRESSURE SYSTEM EXITS FARTHER
OFFSHORE THROUGH TONIGHT, A NEW PUSH OF COLDER, DRIER AIR WILL BE
FELT ACROSS THE REGION ON NORTHWEST BREEZES IN THE WAKE OF THE
DEPARTING LOW PRESSURE AND COLD FRONT. IN ADDITION, A MID-LEVEL
TROUGH WILL BE SETTLING ACROSS THE NORTHEAST TO MID ATLANTIC STATES
AS ARCTIC HIGH PRESSURE GRADUALLY BUILDS EAST FROM THE PLAINS AND
MIDWEST. OVERALL, DRY CONDITIONS ARE EXPECTED THROUGH THE NIGHTTIME
HOURS, SAVE PERHAPS A FEW ISOLATED/SCATTERED SNOW SHOWERS IN THE
POCONOS ON THE NORTHWEST FLOW. WE MOSTLY TOOK A MET/MAV GUIDANCE
BLEND WITH CONTINUITY FOR MINIMUM TEMPS, AND WE EXPECT SOME SINGLE
DIGIT LOW TEMPERATURES IN THE FAR NORTHWEST TO MAINLY TEENS AND
LOWER 20S ELSEWHERE.
&&
.LONG TERM /MONDAY THROUGH SATURDAY/...
A STRONG 1047 MB SURFACE HIGH OVER THE MIDWEST WILL BUILD EASTWARD
INTO THE MID ATLANTIC AND NORTHEAST STATES ON MONDAY. STEADY
PRESSURE RISES FROM THIS PATTERN BE ACCOMPANIED BY A BRISK NW WINDS
THAT USHERS IN THE NEXT SHOT OF COLD ARCTIC AIR. FORECAST MAX TEMPS
GENERALLY IN THE TEENS NORTH AND WEST OF THE FALL LINE AND LOW TO
MID 20S TO THE SOUTH AND EAST. THE HIGHS SHOULD OCCUR IN THE MORNING
AS TEMPS GRADUALLY FALL THROUGHOUT THE DAY OWING TO THE STRONG CAA.
WIND CHILLS AOB ZERO ARE EXPECTED FOR NE PA AND NW NJ AND SINGLE
DIGITS ELSEWHERE. WIND CHILL ADVISORIES WILL LIKELY BE NEEDED FOR
THE POCONOS WITH WIND CHILL VALUES DIPPING BETWEEN 15 AND 20 BELOW
ZERO.
THE CENTER OF THE ARCTIC HIGH IS FORECAST TO SHIFT TOWARD THE
CENTRAL APPALACHIANS MONDAY EVENING AND MID-ATLANTIC COAST EARLY
TUESDAY MORNING. THE PRESSURE GRADIENT WILL RELAX WHICH WILL ALLOW
THE WINDS TO BECOME LIGHT, ESPECIALLY OVERNIGHT. WENT WITH THE
COLDER MOS GUIDANCE FOR LOW TEMPS, IF NOT COLDER IN SPOTS WITH A
EXTENSIVE SNOW COVER. A SIMILAR SETUP OCCURRED YESTERDAY- RECORD LOW
TEMPS WERE SET AND GUIDANCE BIASED WAY TOO WARM. IN THE MONDAY NIGHT
PATTERN, THE CENTER OF THE RIDGE AXIS MOVES OVERHEAD ABOUT 6 HOURS
LATER INTO THE NIGHT COMPARED TO THIS PAST FRIDAY MORNING SO TEMPS
MAY NOT FREE FALL QUITE AS MUCH. WE WILL ALSO LOSE THAT WIND CHILL
FACTOR OVERNIGHT, SO ANY WIND CHILL ADVISORIES FOR THE POCONOS WOULD
NOT BE NECESSARY.
HIGH PRESSURE MOVES OFF THE COAST TUESDAY. SWLY RETURN FLOW AROUND
THE HIGH AND AHEAD OF A CLIPPER SYSTEM TRACKING NORTH OF THE GREAT
LAKES WILL HELP MODERATE THIS ARCTIC AIRMASS A BIT DURING THE
MIDWEEK. TEMPS STILL 15-20F BELOW NORMAL ON TUESDAY AND 5-10F BELOW
ON WEDNESDAY. A COLD FRONT ASSOCIATED WITH THIS CLIPPER WILL MOVE
THRU THE AREA ON WEDNESDAY. THE BEST CHANCE FOR SNOW SHOWERS APPEAR
TO BE AHEAD OF THE FRONT TUESDAY NIGHT AND ESPECIALLY NORTH OF I-78.
ACCUMULATIONS SHOULD BE LIGHT WITH UP TO AN INCH POSSIBLE IN THE
POCONOS.
ON WEDNESDAY NIGHT INTO THURSDAY, AN AREA OF LOW PRESSURE IS
FORECAST TO DEVELOP ALONG THE AFOREMENTIONED FRONTAL BOUNDARY TO
OUR SOUTH. ANY ASSOCIATED PRECIPITATION IS EXPECTED TO REMAIN
MOSTLY TO OUR SOUTH, BUT THERE IS A SLIGHT CHANCE THAT SOME SNOW
MAY MAKE ITS WAY INTO OUR FAR SOUTHERN AND SOUTHEASTERN AREAS. SO
WE WILL KEEP A SLIGHT CHANCE OF SNOW.
COLD TEMPERATURES RETURN BEHIND THIS FRONTAL BOUNDARY FOR THE END
OF THE WEEK. ESPECIALLY AS HIGH PRESSURE MOVES INTO THE AREA
THURSDAY NIGHT INTO FRIDAY. LOWS THURSDAY NIGHT WILL LIKELY GET
INTO THE SINGLE DIGITS TO BELOW ZERO AGAIN. ANOTHER PERIOD OF
SINGLE DIGIT TO BELOW ZERO WIND CHILLS IS EXPECTED WEDNESDAY NIGHT
THROUGH FRIDAY MORNING.
&&
.AVIATION /10Z SUNDAY THROUGH THURSDAY/...
THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG,
KILG, KMIV, KACY AND SURROUNDING AREAS.
EARLY MORNING...IFR CONDITIONS ARE IN PLACE ACROSS THE REGION AND
ARE EXPECTED TO LAST THROUGH THE EARLY MORNING HOURS. ALL SITES
FROM THE COAST TO THE DELAWARE VALLEY REGION HAVE TRANSITIONED
OVER TO RAIN, EXCEPT KABE AND KRDG WHERE LIGHT SNOW OR SOME
FREEZING RAIN IS EXPECTED BEFORE THE PRECIPITATION ENDS AROUND
DAYBREAK. IN FACT, PRECIPITATION IS FORECAST TO END FROM WEST TO
EAST ACROSS THE REGION BETWEEN ABOUT 1000Z AND 1300Z. WINDS ARE
EXPECTED TO REMAIN LIGHT, MAINLY OUT OF THE SOUTHWEST, OR PERHAPS
GO LIGHT AND VARIABLE FOR A TIME.
REST OF SUNDAY...WHILE PRECIPITATION ENDS EARLY, THE LOWER
CIGS/VSBYS, MAINLY IN THE IFR RANGE, ARE EXPECTED TO REMAIN
THROUGH AT LEAST THE MORNING. WHEN EXACTLY THE LOWER CONDITIONS
WILL BREAK WITH A RETURN TO VFR IS A TRICKY FORECAST AT THIS TIME,
AND THERE ARE DIFFERENCES IN THE GUIDANCE WITH RESPECT TO THIS
OCCURRENCE. FOR NOW, WE HAVE KEPT AN IMPROVEMENT TO VFR BETWEEN
AROUND 16Z TO 18Z, BUT THIS IS A LOW CONFIDENCE FORECAST AS THE
NOTICEABLE PUSH OF COLD, DRY AIR INTO THE REGION DOES NOT OCCUR
UNTIL SUNDAY EVENING/NIGHT. WINDS THROUGH THE DAYTIME SUNDAY ARE
EXPECTED TO BECOME MORE WESTERLY AND THEN NORTHWESTERLY, REMAINING
MOSTLY IN THE 4 TO 8 KNOT RANGE.
OUTLOOK...
MONDAY...BREEZY NW WINDS 10-15 KT WILL GUST TO AROUND 25 KT.
GENERALLY VFR ALTHOUGH CAA STRATOCU MAY TRY TO SNEAK INTO ABE/RDG,
WHICH COULD YIELD MVFR CIGS. CONFIDENCE LOW TO MODERATE ON THIS
HAPPENING.
MONDAY NIGHT THROUGH TUESDAY...VFR AND LIGHT WINDS.
TUESDAY NIGHT AND WEDNESDAY MORNING...MAINLY VFR BUT LOCALIZED/
TEMPORARY RESTRICTIONS POSSIBLE IN SCT SNOW SHOWERS. BEST CHANCE TO
SEE ANY SNOW IS ABE.
WEDNESDAY AFTERNOON THROUGH THURSDAY...VFR. BREEZY NW WINDS RETURN.
&&
.MARINE...
**SINCE MUCH OF DELAWARE BAY IS COVERED BY ICE WE WILL CONTINUE
TO ADD THE PHRASING "ON ICE FREE WATERS" FOR THE FIRST FOUR
PERIODS OF THE FORECAST**
WHILE LIGHTER WINDS BELOW 20 KNOTS ARE EXPECTED FOR OUR AREA WATERS
THROUGH TODAY, SEAS ON THE COASTAL WATERS SHOULD REMAIN AROUND 5
FEET OR SO, ESPECIALLY FOR THE OUTER WATERS AWAY FROM THE NEAR
SHORE. WE THEREFORE CONTINUE THE SMALL CRAFT ADVISORY FOR OUR
COASTAL WATERS THROUGH TODAY, ALTHOUGH CONDITIONS COULD BRIEFLY FALL
BELOW CRITERIA FOR A TIME. LATER TONIGHT, NORTHWESTERLY WINDS WILL
INCREASE, WITH GUSTS REACHING AROUND 25 KNOTS. SEAS MAY ALSO
INCREASE SOME IN RESPONSE. THE SCA WILL CONTINUE FOR THE COASTAL
WATERS THROUGH TONIGHT AND INTO MONDAY.
FOR THE DELAWARE BAY, BOTH SEAS AND WINDS ARE EXPECTED TO REMAIN AT
SUB-ADVISORY LEVELS THROUGH TODAY AND TONIGHT, WITH CONDITIONS THEN
MEETING SCA CRITERIA INTO MONDAY AS NORTHWESTERLY WINDS INCREASE.
OUTLOOK...
MONDAY AND MONDAY NIGHT...SCA ISSUED FOR BOTH THE DE BAY AND COASTAL
ZONES WITH NW GUSTS TO AROUND 25 KT. WINDS RELAX MONDAY NIGHT BUT
SCA LEVEL WINDS MAY LINGER INTO THE EARLY EVENING.
TUESDAY THROUGH WEDNESDAY...SW WINDS AND SEAS WILL APPROACH SCA
LEVELS LATE TUESDAY NIGHT INTO WEDNESDAY MORNING BUT WILL LIKELY
BE JUST BELOW.
WEDNESDAY NIGHT AND THURSDAY...BETTER CHANCE AT SCA CONDITIONS
IN NW FLOW PATTERN.
&&
.PHI WATCHES/WARNINGS/ADVISORIES...
PA...WINTER STORM WARNING UNTIL 6 AM EST EARLY THIS MORNING FOR
PAZ060>062-101>103-105.
WINTER STORM WARNING UNTIL 9 AM EST THIS MORNING FOR PAZ070-
071-104-106.
WINTER WEATHER ADVISORY UNTIL 6 AM EST EARLY THIS MORNING FOR
PAZ054-055.
NJ...WINTER STORM WARNING UNTIL 6 AM EST EARLY THIS MORNING FOR
NJZ007>010-015.
FREEZING RAIN ADVISORY UNTIL 9 AM EST THIS MORNING FOR NJZ021-
022.
WINTER STORM WARNING UNTIL 9 AM EST THIS MORNING FOR
NJZ012>014-016>020-026-027.
WINTER WEATHER ADVISORY UNTIL 6 AM EST EARLY THIS MORNING FOR
NJZ001.
DE...FREEZING RAIN ADVISORY UNTIL 9 AM EST THIS MORNING FOR DEZ002.
WINTER STORM WARNING UNTIL 9 AM EST THIS MORNING FOR DEZ001.
MD...WINTER STORM WARNING UNTIL 6 AM EST EARLY THIS MORNING FOR
MDZ008.
FREEZING RAIN ADVISORY UNTIL 9 AM EST THIS MORNING FOR MDZ015.
WINTER STORM WARNING UNTIL 9 AM EST THIS MORNING FOR MDZ012.
MARINE...SMALL CRAFT ADVISORY UNTIL 6 PM EST MONDAY FOR ANZ450>455.
SMALL CRAFT ADVISORY FROM 6 AM TO 6 PM EST MONDAY FOR ANZ430-
431.
&&
$$
SYNOPSIS...KLEIN
NEAR TERM...KLINE
SHORT TERM...KLINE
LONG TERM...KLEIN/ROBERTSON
AVIATION...KLEIN/KLINE
MARINE...KLEIN/KLINE
AREA FORECAST DISCUSSION
NWS TALLAHASSEE FL
627 AM EST Sun Feb 22 2015
.Update...
The eastward spread of light isentropic showers was missed by
pretty much all of the available hires guidance. Have expanded
PoPs eastward and weighted the forecast towards the HRRR for the
next several hours. Still expect the isentropic rain to weaken
and become more sparse through the early afternoon as discussed
below. At this time the remainder of the forecast remains valid,
though temperature trends will have to be monitored across the Big
Bend and southern GA should rain continue longer than expected.
This could result in lower temps than currently advertised.
&&
.Prev Discussion [342 AM EST]...
.Near Term [Through Today]...
Zonal flow aloft will dominate the Southeast today, with a broad
northern stream trough in the northeastern quadrant of the
country, and an upper low cutting off over the Central Great
Basin and west coast. At the surface, a regional subjective
analysis depicts a cold front draped southwest to northeast from
the southern Mississippi Valley into northern Alabama. Extending
east-northeast from northern Alabama is a quasi-stationary
boundary draped up the lee side of the Appalachians. The large
area of light to moderate rain was being forced out ahead of the
surface front, associated with a weak southern stream anomaly.
Another area of light rain along near the Tri-State intersection
is being forced in the near surface 290-295K window.
As warming begins across the Southeast today, the slope of the
isentropes will dampen and the aforementioned area of rain should
come to an end by mid-afternoon. Though, not before spreading an
area of light rain primarily along and west of the Apalachicola
and Chattahoochee rivers. The larger area of precip across the
Southeast this morning will lift northeast with the upper-level
shortwave and the focus for the majority of rainfall across the
Southeast will shift back to the surface front. The front is
expected to just barely reach our southeast Alabama and extreme
western Georgia counties late this afternoon as surface high
pressure builds south. This will yield the best chance for rain
later this afternoon along and northwest of a line from Ben Hill
county to Walton county. Total rain accumulations through today
shouldn`t top a half an inch across southeast Alabama, and a
quarter of an inch elsewhere.
With the sharp precip gradient, a similar temperature gradient is
also expected. Low 70s should be anticipated in aforementioned
areas impacted by rain, while middle to even upper 70s (across
the Suwannee Valley) should be expected elsewhere.
.Short Term [Tonight Through Tuesday]...
The cold front mentioned above will push through the forecast area
tonight into Monday. The best chance of rain will be across the
northwest half of the area as the front will be weakening as it
moves through. Model disagreements become apparent by Tuesday as
the NAM and ECMWF spread additional light rain into the area with
a weak upper level shortwave while the GFS is drier. The official
forecast went with a compromise and shows 30-50% PoPs. With an
increase in cloud cover expected on Tuesday, high temperatures
will be held down somewhat with lower 50s expected across the
north and mid 50s to near 60 across the southeast big bend.
.Long Term [Tuesday Night Through Sunday]...
A more significant system is possible on Wednesday with both the
GFS and ECMWF indicating a fairly vigorous upper level shortwave
with a surface low moving along the coast. With the 00z models in
general agreement on the timing, PoPs were bumped up to 70% for
Wednesday. This looks like a decent rainfall producer with a
couple of inches possible across the area. With the surface low
expected to track south of the area, the airmass currently looks
too stable for thunderstorms across our area. After the Wednesday
system, another system is possible for next weekend. Overall, high
temperatures are expected to be a bit below average with lows
near average.
.Aviation...
[Through 12z Monday] MVFR to IFR ceilings should be expected in
and around areas of rainfall through mid-morning. Thereafter, VFR
ceilings should be expected at all terminals but DHN and ABY where
MVFR will prevail with light to moderate rain.
.Marine...
Southerly winds will be subsiding today. However by late tonight
into Monday, a cold front will move through the coastal waters,
bringing an increase in northerly winds possibly to cautionary
levels mainly west of Apalachicola. Winds are then expected to be
light for Tuesday before increasing again on Wednesday to near
advisory levels as an area of low pressure moves along the coast.
.Fire Weather...
Hazardous fire weather conditions are not expected over the next
several days.
.Hydrology...
Several rounds of rainfall are possible this week with the best
chance for an areawide moderate to possibly heavy rainfall event
expected on Wednesday. Total rainfall is generally expected to be
in the 2-3 inch range with isolated higher totals possible. This
will cause rises on area rivers and may bring a few of our sites
back up to action stage. At this time, flooding is not expected,
although if widespread rainfall amounts were to increase above 3
inches, then the Kinchafoonee Creek as well as the Ochlockonee and
Aucilla Rivers could come close to minor flood stage.
&&
.Preliminary Point Temps/PoPs...
Tallahassee 71 55 69 49 57 / 70 20 20 40 50
Panama City 65 57 63 48 54 / 70 20 20 40 50
Dothan 71 49 59 41 51 / 70 50 20 40 50
Albany 73 51 61 40 51 / 70 50 20 30 40
Valdosta 76 55 68 45 53 / 60 20 20 40 50
Cross City 76 54 72 50 60 / 30 10 20 30 50
Apalachicola 66 58 68 51 57 / 70 10 20 40 50
&&
.TAE Watches/Warnings/Advisories...
FL...RIP CURRENT RISK through this evening for Coastal Bay-Coastal
Gulf-South Walton.
GA...None.
AL...None.
GM...None.
&&
$$
NEAR TERM...HARRIGAN
SHORT TERM...DVD
LONG TERM...DVD
AVIATION...HARRIGAN
MARINE...DVD
FIRE WEATHER...HARRIGAN
HYDROLOGY...DVD
AREA FORECAST DISCUSSION
NWS COLUMBIA SC
629 AM EST SUN FEB 22 2015
.SYNOPSIS...
A STATIONARY FRONT WILL BE SITUATED WEST OF THE AREA THROUGH THE
DAY. BY TONIGHT A COLD FRONT WILL BE MOVING INTO THE AREA FROM THE
WEST. THIS WILL BRING RAIN CHANCES TO MUCH OF THE REGION INTO
MONDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
ONE BATCH OF RAINFALL CURRENTLY MOVING THROUGH THE REGION APPEARS TO
HAVE BEEN HANDLED FAIRLY WELL BY THE LATEST HRRR MODEL. THE HRRR
PUSHES THE MORE WIDESPREAD RAINFALL EAST OF MOST OF THE AREA BY
14Z...WITH SCATTERED SHOWERS STILL POSSIBLE THROUGH LATE MORNING.
MOST MODELS DO TRY TO INCREASE THE RAIN COVERAGE ONCE AGAIN LATER IN
THE AFTERNOON...SO HAVE TRIED TO SHOW THAT TREND.
CURRENT SURFACE ANALYSIS SHOWS A STATIONARY FRONT STILL SITUATED
ACROSS THE WESTERN MIDLANDS AND THE NORTHERN CSRA. TEMPERATURES
WEST OF THE FRONT REMAIN AROUND 40 THIS MORNING...WHILE READINGS TO
THE EAST ARE GENERALLY IN THE 50S. AFTERNOON TEMPS WILL BE HIGHLY
DEPENDENT UPON WHERE THIS FRONT IS THROUGHOUT THE DAY. DO FORECAST
THIS FRONT TO LIFT SLIGHTLY WESTWARD INTO THE UPSTATE BY THE
AFTERNOON...THUS AM FORECASTING HIGHS IN THE 60S ACROSS MOST OF THE
CWA. HIGHS ACROSS THE EXTREME WEST COULD BE HELD DOWN IF THE COLDER
AIR DOES NOT RETREAT FAR ENOUGH WEST DURING THE MORNING.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH MONDAY NIGHT/...
TONIGHT...THE COLD FRONT WILL CONTINUE CROSSING THE AREA FROM THE
NORTHWEST TONIGHT AND WILL BE ALONG THE COAST BY 12Z MONDAY MORNING.
SHORTWAVE ENERGY WILL ALSO MOVE ACROSS THE REGION OVERNIGHT.
MODELS SHOW ABUNDANT MOISTURE ALONG AND AHEAD OF THE FRONT WITH
PWAT VALUES UP TO 1.4 INCHES IN THE EASTERN MIDLANDS AND CSRA.
HAVE INCREASED POPS OVERNIGHT DUE TO MODEL CONSENSUS. RAIN MAY BE
MODERATE IN INTENSITY AT TIMES. 00Z TO 12Z MONDAY QPF IS AROUND
HALF AN INCH TO OVER THREE QUARTERS OF AN INCH. TIGHTENING
PRESSURE GRADIENT AND COLD AIR ADVECTION BEHIND THE FRONT WILL
PROMOTE INCREASING WIND SPEEDS TOWARD DAYBREAK MONDAY. OVERCAST
SKIES FAVOR ABOVE NORMAL LOWS...IN THE 40S.
MONDAY AND MONDAY NIGHT...BROAD TROUGH OVER THE EASTERN HALF OF THE
COUNTRY WILL PROMOTE WESTERLY FLOW ALOFT FOR MONDAY. SURFACE HIGH
PRESSURE CENTERED OVER THE MIDDLE PART OF THE COUNTRY WILL SHIFT
EAST...RIDGING INTO THE REGION. THE FRONT IS PROGGED TO STALL
ALONG THE COAST. THE BETTER MOISTURE SHIFTS NORTHEAST BY MIDDAY.
TEMPERATURES WILL STRUGGLE THROUGH THE DAY ON MONDAY AS COLD AIR
ADVECTION INCREASES ACROSS THE AREA. MODEL GUIDANCE SHOWS
TEMPERATURES DROPPING A FEW DEGREES LATE MONDAY MORNING THEN
MAKING VERY LITTLE PROGRESS THROUGH THE AFTERNOON. HAVE USED A
BLEND OF HOURLY MODEL TEMPERATURE GUIDANCE TO COME UP WITH A NON-
DIURNAL TREND FOR MONDAY. EXPECT AFTERNOON TEMPERATURES IN THE
40S.
&&
.LONG TERM /TUESDAY THROUGH SATURDAY/...
LONG TERM PATTERN CONTINUES TO LOOK COLD AND UNSETTLED. THE GFS
AND ECMWF SHOW A WAVE OF LOW PRESSURE DEVELOPING OFF THE SOUTHEAST
COAST TUESDAY PROMOTING INCREASED MOISTURE INTO THE REGION.
CONTINUED TO INDICATE ONLY A SLIGHT CHANCE OF RAIN TUESDAY AS THE
BETTER MOISTURE APPEARS TO REMAIN ALONG THE COAST. MODELS
INDICATE SURFACE LOW PRESSURE DEVELOPING ALONG THE WESTERN GULF ON
WEDNESDAY AND SHIFTING NORTHEASTWARD ACROSS FLORIDA WEDNESDAY
NIGHT. HAVE CONTINUED TO INDICATE A CHANCE OF RAIN WEDNESDAY AS
MOISTURE INCREASES ACROSS THE AREA ASSOCIATED WITH THIS FEATURE.
THE GFS KEEPS THE BETTER MOISTURE TO OUR SOUTHEAST WEDNESDAY NIGHT
WHILE THE ECMWF IS MORE MOIST ACROSS THE CWA. GFS POPS ARE MUCH
LOWER WEDNESDAY NIGHT WHICH IS CLOSER TO OUR FORECAST POPS
CURRENTLY. MAY HAVE WINTER PRECIP IF THE WETTER ECMWF SCENARIO IS
CORRECT. MODELS SHOW HIGH PRESSURE BUILDING IN FOR THE END OF THE
WEEK AND A POSSIBLE WEDGE SETTING UP HEADING INTO THE WEEKEND WITH
INCREASED MOISTURE. THERE IS SOME POTENTIAL FOR WINTRY WEATHER
WITH THIS FEATURE AS WELL BUT HIGH UNCERTAINTY REMAINS.
&&
.AVIATION /12Z SUNDAY THROUGH THURSDAY/...
VFR CONDITIONS EXPECTED THROUGH 18Z...THEN CONDITIONS COULD
DETERIORATE TO MVFR THROUGH THE AFTERNOON. IFR POSSIBLE LATE
TONIGHT.
A STATIONARY FRONT CONTINUES TO BE SHOWN OFF TO THE WEST OF ALL TAF
SITES THIS MORNING. MAINLY MID AND UPPER LEVEL CLOUDS WILL BE OVER
THE AREA THIS MORNING. WINDS OFF THE SURFACE HAVE DECREASED TO
AROUND 25 KNOTS...SO HAVE REMOVED MENTION OF LLWS AT THIS TIME.
BASED OFF OF CONDITIONS FURTHER UPSTREAM CLOSER TO THE FRONT...HAVE
LEANED MORE TOWARDS THE NAM GUIDANCE...WHICH HOLDS OFF ON THE LOWER
CEILINGS UNTIL LATER IN THE MORNING. MVFR CONDITIONS WILL THEN
PERSIST THROUGH THE LATE AFTERNOON AND INTO THE EARLY PORTIONS OF
THE NIGHT. GUIDANCE IS SHOWING A GREATER CHANCE FOR IFR DEVELOPMENT
BY 06Z AT ALL SITES.
RAIN CHANCES WILL CONTINUE THROUGH THE MORNING AS ISENTROPIC
LIFT BRINGS MOISTURE ACROSS THE REGION. THERE MAY BE A BREAK IN THE
PRECIP LATER THIS MORNING...THEN GUIDANCE IS SHOWING ANOTHER CHANCE
FOR RAINFALL LATER THIS AFTERNOON INTO THE OVERNIGHT HOURS.
EXTENDED AVIATION OUTLOOK...EXPECT A CHANCE OF LIGHT RAIN WITH MVFR
RESTRICTIONS...POSSIBLY IFR...MONDAY MORNING. VFR EXPECTED MONDAY
AFTERNOON. RESTRICTIONS POSSIBLE WITH A CHANCE OF RAIN WED.
&&
.CAE WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
GA...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
1058 AM EST SUN FEB 22 2015
.SYNOPSIS...
THE LOW PRESSURE THAT BROUGHT THE SNOW TO THE REGION WILL TRACK
WELL OFF THE EAST COAST TODAY AS YET ANOTHER ARCTIC FRONT CROSSES
THE REGION THIS EVENING. BITTERLY COLD AIR WILL FOLLOW FOR MONDAY
INTO TUESDAY WITH SUB ZERO TEMPERATURES AND AT TIMES DANGEROUSLY
COLD WIND CHILLS. SOME MODERATION IS EXPECTED TUESDAY AND
ESPECIALLY WEDNESDAY AS HIGHS REACH INTO THE 20S AND LOWER 30S.
&&
.NEAR TERM /THROUGH MONDAY/...
11 AM UPDATE... JUST MINOR TWEAKS MADE TO SKY AND TEMP GRIDS
ATTM...BASED ON THE LATEST OBSERVATIONAL DATA.
RECENT SAT IMAGERY HAS SHOWN SOME BREAKS IN THE LOW CLDNS OVER
PTNS OF WRN/CNTRL NY AND NRN PA. ALTHOUGH WE EXPECT TO SEE SOME
THINNING OF THE CLDS THIS AFTN...WE THINK CLDS WILL STILL HAVE THE
UPPER HAND OVERALL...GIVEN THE STEEP THERMAL INVERSION NOTED ON THE 12Z
KBUF SNDG...AND THE LIKELIHOOD THAT BLYR MOISTURE WILL BE TRAPPED
BLO THIS FEATURE.
DESPITE THE CLDS...TEMPS WILL BE FAIRLY MILD COMPARED TO OUR
RECENT BITTER COLD STRETCH...WITH HIGHS IN THE UPR 20S-LWR 30S IN
MOST AREAS.
IT STILL APPEARS THAT MOST OF THE FLRYS/-SHSN EXPECTED ALG AND AHD
OF TNT`S ARCTIC FROPA WILL HOLD OFF TIL VERY LATE IN THE DAY...OR
MORE LIKELY THIS EVE.
PREV DISC... THE LAST OF THE LIGHT SNOW AND FLURRIES WAS EXITING
NE PA AND SULLIVAN COUNTY AT THIS TIME AS AN UPPER LEVEL WAVE
RIPPLES INTO NY AND PA ERLY THIS MORNING. THERE HAS BEEN NO
REPORTS OF FREEZING DRIZZLE ANYWHERE IN CNTRL OR WRN NY OR NRN AND
WRN PA AND LOOKING AT THE SOUNDINGS I REALLY DON/T SEE ANY
POTENTIAL. SFC WET BULB TEMPERATURES WERE RUNNING ARND -7C AND
WITH UPLIFT IT WUD BE COLD ENUF FOR SOME ICE CRYSTAL GROWTH. MODELS
ARE SHOWING SUBSDC BEHIND THIS UPPER WAVE ANYWAY SO NOT EXPECTING
ANY WIDESPREAD FREEZING DRIZZLE. THUS HAVE DROPPED WINTER WEATHER
ADVISORY.
THE REST OF THE MORNING INTO THE AFTERNOON LOOKS TO BE CLOUDY AS
CAA BEGINS AND TRAPS MOISTURE UNDER A SHARP INVERSION ARND 900
MB. ANOTHER ARCTIC FRONT IS POISE TO PASS THRU THE REGION THIS
EVENING SO MUCH OF THE AFTERNOON WILL BE ALMOST SEASONABLE IN
TEMPERATURES. ARCTIC FRONT PASSES BY THIS EVENING. SOUNDINGS
SUGGEST THAT THE INVERSION RISES TO ABT 850 MB WHEN THE ARCTIC
PASSES BY WITH MINIMAL CAPE. THERE CUD BE SOME SNOW SQUALLS BUT
AT THIS TIME IT DOESN`T LOOK LIKE A MAJOR SNOW SQUALL EVENT.
HOWEVER...IT WILL DEPEND ON HOW WARM IT GETS THIS AFTERNOON.
CONVECTION ALLOWING MODELS THIS FAR OUT(WRF_NMM AND WRF_ARW) ARE
NOT SHOWING ANYTHING SIGNIFICANT EITHER. IT WILL BE INTERESTING TO
SEE IF THE RAP AND HRRR CATCH ONTO SOMETHING WHEN THEY GET TO THIS
EVENINGS TIME PERIOD. THIS IS SOMETHING TO PASS ONTO THE NEXT
SHIFT.
AFTER ARCTIC FRONT PASSES BY...THE USUAL 290 DEGREE LES SETS UP
BUT IT LIKELY WILL BE TOO DRY FOR ANY MAJOR ACCUMULATIONS
DOWNWIND...MAYBE SEVERAL INCHES AT BEST. BIG STORY WILL BE ANOTHER
SHOT OF ARCTIC AIR ON FAIRLY STRG NW WINDS. MINS MONDAY AM WILL BE
FROM ZERO TO 15 BELOW IN NY STATE WITH WIND CHILLS BETWEEN 20 AND
30 BELOW ZERO AS IT STANDS NOW. SO HAVE HOISTED A WIND CHILL WATCH
FOR TONIGHT AND MONDAY MORNING TO GIVE EVERYONE A HEAD`S UP ON
ANOTHER COLD MONDAY MORNING. THE WC WATCH IS FOR NY COUNTIES
EXCEPT SULLIVAN CO AND FOR NRN PA COUNTIES IN ERN PA.
MONDAY WILL BE ANOTHER COLD AND WINDY DAY WITH TEMPERATURES
STRUGGLING TO GET OUT ABOVE ZERO IN NRN NY AND BARELY REACHING 10
DEGREES IN NE PA.
&&
.SHORT TERM /MONDAY NIGHT THROUGH TUESDAY NIGHT/...
FOR MONDAY NIGHT...YET ANOTHER BRUTALLY COLD NIGHT IS IN STORE AS
THIS HISTORICALLY COLD FEBRUARY CONTINUES. MINS LIKELY WILL DROP
TO 5 BELOW TO 20 BELOW OR LOWER. THEN TUESDAY THERE IS A SOUTHERLY
FLOW IN ADVANCE OF ANOTHER SYSTEM TRACKING INTO QUEBEC. THIS WILL
LEAD TO SOME MODERATION AND A CHANCE OF SNOW SHOWERS BY TUESDAY
NIGHT.
&&
.LONG TERM /WEDNESDAY THROUGH SATURDAY/...
EASTERN TROF IS EXPECTED TO CONTINUE THROUGH THE END OF THE WEEK
WITH RISING HEIGHTS AND PERHAPS ZONAL FLOW BY NEXT WEEKEND.
ON WEDNESDAY THE NEXT ARCTIC FRONT WILL PASS THROUGH THE AREA WITH
SCATTERED SNOW SHOWERS AND MORE FRIGID AIR. WEDNESDAY NIGHT
THROUGH FRIDAY NIGHT TEMPS WILL RUN 15 TO 25 DEGREES BELOW NORMAL.
NORTHWEST FLOW FOLLOWING THE FRONT MAY PRODUCE SOME SCATTERED LAKE
EFFECT SNOW SHOWERS AND FLURRIES BUT NOTHING REAL SIGNIFICANT DUE
TO SHORT FETCH AND PLENTY OF ICE ON LAKE ONTARIO. IN GENERAL A
FAIRLY QUIET BUT COLD PERIOD. SATURDAY AND SUNDAY A SYSTEM IN THE
MID ATLANTIC MAY BRUSH THE FA ESPECIALLY THE SOUTHERN PORTION,
INCLUDED CHC/SLIGHT CHC POPS.
&&
.AVIATION /16Z SUNDAY THROUGH THURSDAY/...
ABUNDANT LOW LEVEL MOISTURE TRAPPED UNDER AN INVERSION WILL KEEP
MVFR CIGS THROUGH TODAY. THIS EVENING AN ARCTIC FRONT WILL PASS
THROUGH PRIMARILY BETWEEN 00Z-06Z, BRINGING MVFR SNOW SHOWERS.
AFTER 06Z, SNOW SHOWERS SHOULD END BUT MVFR CIGS WILL CONTINUE
THROUGH END OF TAF PERIOD AT MOST TERMINALS.
LIGHT AND VARIABLE WINDS BECOMING NW BY MID MORNING AROUND 5-8
KNOTS.
.OUTLOOK...
MON...MVFR/IFR RESTRICTIONS PSBL IN SNOW SHWRS.
MON NGT-TUE...VFR.
TUE NGT-WED...RESTRICTIONS PSBL AGN IN SNOW SHWRS/LGT SNOW...ESP CNY.
WED NGT-THU...MAINLY VFR.
&&
.BGM WATCHES/WARNINGS/ADVISORIES...
PA...WIND CHILL WATCH FROM LATE TONIGHT THROUGH MONDAY MORNING FOR
PAZ038-039.
NY...WIND CHILL WATCH FROM LATE TONIGHT THROUGH MONDAY MORNING FOR
NYZ009-015>018-022>025-036-037-044>046-055>057.
&&
$$
SYNOPSIS...DJN
NEAR TERM...DJN/MLJ
SHORT TERM...DJN
LONG TERM...RRM
AVIATION...RRM
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
643 AM EST SUN FEB 22 2015
.SYNOPSIS...
THE LOW PRESSURE THAT BROUGHT THE SNOW TO THE REGION WILL TRACK
WELL OFF THE EAST COAST TODAY AS YET ANOTHER ARCTIC FRONT CROSSES
THE REGION THIS EVENING. BITTERLY COLD AIR WILL FOLLOW FOR MONDAY
INTO TUESDAY WITH SUB ZERO TEMPERATURES AND AT TIMES DANGEROUSLY
COLD WIND CHILLS. SOME MODERATION IS EXPECTED TUESDAY AND
ESPECIALLY WEDNESDAY AS HIGHS REACH INTO THE 20S AND LOWER 30S.
&&
.NEAR TERM /THROUGH MONDAY/...
THE LAST OF THE LIGHT SNOW AND FLURRIES WAS EXITING NE PA AND
SULLIVAN COUNTY AT THIS TIME AS AN UPPER LEVEL WAVE RIPPLES INTO
NY AND PA ERLY THIS MORNING. THERE HAS BEEN NO REPORTS OF FREEZING
DRIZZLE ANYWHERE IN CNTRL OR WRN NY OR NRN AND WRN PA AND LOOKING
AT THE SOUNDINGS I REALLY DON/T SEE ANY POTENTIAL. SFC WET BULB
TEMPERATURES WERE RUNNING ARND -7C AND WITH UPLIFT IT WUD BE COLD
ENUF FOR SOME ICE CRYSAL GROWTH. MODELS ARE SHOWING SUBSDC BEHIND
THIS UPPER WAVE ANYWAY SO NOT EXPECTING ANY WIDESPREAD FREEZING
DRIZZLE. THUS HAVE DROPPED WINTER WEATHER ADVISORY.
THE REST OF THE MORNING INTO THE AFTERNOON LOOKS TO BE CLOUDY AS
CAA BEGINS AND TRAPS MOISTURE UNDER A SHARP INVERSION ARND 900
MB. ANOTHER ARCTIC FRONT IS POISE TO PASS THRU THE REGION THIS
EVENING SO MUCH OF THE AFTERNOON WILL BE ALMOST SEASONABLE IN
TEMPERATURES. ARCTIC FRONT PASSES BY THIS EVENING. SOUNDINGS
SUGGEST THAT THE INVERSION RISES TO ABT 850 MB WHEN THE ARCTIC
PASSES BY WITH MINIMAL CAPE. THERE CUD BE SOME SNOW SQUALLS BUT
AT THIS TIME IT DOESN`T LOOK LIKE A MAJOR SNOW SQUALL EVENT.
HOWEVER...IT WILL DEPEND ON HOW WARM IT GETS THIS AFTERNOON.
CONVECTION ALLOWING MODELS THIS FAR OUT(WRF_NMM AND WRF_ARW) ARE
NOT SHOWING ANYTHING SIGNIFICANT EITHER. IT WILL BE INTERESTING TO
SEE IF THE RAP AND HRRR CATCH ONTO SOMETHING WHEN THEY GET TO THIS
EVENINGS TIME PERIOD. THIS IS SOMETHING TO PASS ONTO THE NEXT
SHIFT.
AFTER ARCTIC FRONT PASSES BY...THE USUAL 290 DEGREE LES SETS UP
BUT IT LIKELY WILL BE TOO DRY FOR ANY MAJOR ACCUMULATIONS
DOWNWIND...MAYBE SEVERAL INCHES AT BEST. BIG STORY WILL BE ANOTHER
SHOT OF ARCTIC AIR ON FAIRLY STRG NW WINDS. MINS MONDAY AM WILL BE
FROM ZERO TO 15 BELOW IN NY STATE WITH WIND CHILLS BETWEEN 20 AND
30 BELOW ZERO AS IT STANDS NOW. SO HAVE HOISTED A WIND CHILL WATCH
FOR TONIGHT AND MONDAY MORNING TO GIVE EVERYONE A HEAD`S UP ON
ANOTHER COLD MONDAY MORNING. THE WC WATCH IS FOR NY COUNTIES
EXCEPT SULLIVAN CO AND FOR NRN PA COUNTIES IN ERN PA.
MONDAY WILL BE ANOTHER COLD AND WINDY DAY WITH TEMPERATURES
STRUGGLING TO GET OUT ABOVE ZERO IN NRN NY AND BARELY REACHING 10
DEGREES IN NE PA.
&&
.SHORT TERM /MONDAY NIGHT THROUGH TUESDAY NIGHT/...
FOR MONDAY NIGHT...YET ANOTHER BRUTALLY COLD NIGHT IS IN STORE AS
THIS HISTORICALLY COLD FEBRUARY CONTINUES. MINS LIKELY WILL DROP
TO 5 BELOW TO 20 BELOW OR LOWER. THEN TUESDAY THERE IS A SOUTHERLY
FLOW IN ADVANCE OF ANOTHER SYSTEM TRACKING INTO QUEBEC. THIS WILL
LEAD TO SOME MODERATION AND A CHANCE OF SNOW SHOWERS BY TUESDAY
NIGHT.
&&
.LONG TERM /WEDNESDAY THROUGH SATURDAY/...
EASTERN TROF IS EXPECTED TO CONTINUE THROUGH THE END OF THE WEEK
WITH RISING HEIGHTS AND PERHAPS ZONAL FLOW BY NEXT WEEKEND.
ON WEDNESDAY THE NEXT ARCTIC FRONT WILL PASS THROUGH THE AREA WITH
SCATTERED SNOW SHOWERS AND MORE FRIGID AIR. WEDNESDAY NIGHT
THROUGH FRIDAY NIGHT TEMPS WILL RUN 15 TO 25 DEGREES BELOW NORMAL.
NORTHWEST FLOW FOLLOWING THE FRONT MAY PRODUCE SOME SCATTERED LAKE
EFFECT SNOW SHOWERS AND FLURRIES BUT NOTHING REAL SIGNIFICANT DUE
TO SHORT FETCH AND PLENTY OF ICE ON LAKE ONTARIO. IN GENERAL A
FAIRLY QUIET BUT COLD PERIOD. SATURDAY AND SUNDAY A SYSTEM IN THE
MID ATLANTIC MAY BRUSH THE FA ESPECIALLY THE SOUTHERN PORTION,
INCLUDED CHC/SLIGHT CHC POPS.
&&
.AVIATION /12Z SUNDAY THROUGH THURSDAY/...
ABUNDANT LOW LEVEL MOISTURE TRAPPED UNDER AN INVERSION WILL KEEP
MVFR CIGS THROUGH TODAY. THIS EVENING AN ARCTIC FRONT WILL PASS
THROUGH PRIMARILY BETWEEN 00Z-06Z, BRINGING MVFR SNOW SHOWERS.
AFTER 06Z, SNOW SHOWERS SHOULD END BUT MVFR CIGS WILL CONTINUE
THROUGH END OF TAF PERIOD AT MOST TERMINALS.
LIGHT AND VARIABLE WINDS BECOMING NW BY MID MORNING AROUND 5-8
KNOTS.
.OUTLOOK...
MON...MVFR/IFR RESTRICTIONS PSBL IN SNOW SHWRS.
MON NGT-TUE...VFR.
TUE NGT-WED...RESTRICTIONS PSBL AGN IN SNOW SHWRS/LGT SNOW...ESP CNY.
WED NGT-THU...MAINLY VFR.
&&
.BGM WATCHES/WARNINGS/ADVISORIES...
PA...WIND CHILL WATCH FROM LATE TONIGHT THROUGH MONDAY MORNING FOR
PAZ038-039.
NY...WIND CHILL WATCH FROM LATE TONIGHT THROUGH MONDAY MORNING FOR
NYZ009-015>018-022>025-036-037-044>046-055>057.
&&
$$
SYNOPSIS...DJN
NEAR TERM...DJN
SHORT TERM...DJN
LONG TERM...RRM
AVIATION...RRM
AREA FORECAST DISCUSSION
NWS RALEIGH NC
1035 AM EST SUN FEB 22 2015
.SYNOPSIS...A COLD FRONT WILL MOVE EAST...CROSSING CENTRAL NC LATE
THIS AFTERNOON AND EVENING. LOW PRESSURE WILL DEVELOP AND MOVE ALONG
THE FRONT TO OUR SOUTH TONIGHT. CHILLY HIGH PRESSURE WILL NOSE INTO
OUR AREA FROM THE NORTHWEST MONDAY AND MONDAY NIGHT.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 1035 AM SUNDAY...
THE PRE-FRONTAL RAIN BAND IS DISSIPATING AND EXITING THE COASTAL
PLAN ON THE HEELS OF THE LOW-LEVEL JET MOVING UP THE MID-ATLANTIC
COAST. RADAR TRENDS WARRANT CATEGORICAL POPS OVER THE SOUTHERN
COASTAL PLAIN FOR A COUPLE MORE HOURS...AND THEREAFTER THE HRRR
SUGGESTS ONLY A SLIGHT CHANCE DURING THE EARLY AFTERNOON. THERE IS
AN AREA OF SPOTTY PRECIP ASSOCIATED WITH A WEAK WAVE OF LOW PRESSURE
ALONG THE SYNOPTIC FRONTAL ZONE APPROACHING THE ATLANTA METRO
AREA...AND THE HRRR SHOWS THAT PRECIP MOVING INTO THE SOUTHERN CWA
BY 00Z. THE ASSOCIATED WARM ADVECTION IS WEAK...SO ITS UNCLEAR HOW
LARGE OF AN AREA WILL BE AFFECTED. WILL SHOW A CHANCE POP IN
THE SOUTHEAST AFTER 22Z.
THE TEMPERATURE FORECAST TODAY IS STILL UNCERTAIN WITH GUIDANCE ALL
OVER THE PLACE. THE COLD FRONT IS STILL WEST OF THE
MOUNTAINS...WHILE THE WEDGE FRONT IS HUNG UP BETWEEN THE US-1 AND I-
95 CORRIDORS. WEAK ADVECTION AHEAD OF THE COLD FRONT WILL LEAVE
TEMPS TO BE MAINLY INFLUENCED BY HEATING. VISIBLE IMAGERY SHOWS
SOME BREAKS IN THE CLOUDS WITH THE WESTERLY FLOW ALOFT...BUT IT MAY
TAKE A LITTLE WHILE TO ERODE THE STRATUS THAT APPEARS TO BE AT LEAST
2000FT THICK PER PIREPS AND RAP SOUNDINGS. EXPECT HIGHS TO
ULTIMATELY RANGE FROM THE UPPER 40S IN THE FAR NORTHWEST TO THE
UPPER 50S IN THE SOUTHEAST...THOUGH ADMITTEDLY CONFIDENCE IS BELOW
AVERAGE. -BLS
TONIGHT: ANA-FRONTAL PRECIP WILL QUICKLY SPREAD/FILL NORTH INTO THE
AREA BETWEEN 04 TO 12Z IN RESPONSE TO MOIST LOW-LEVEL UPGLIDE ALONG
...WITH FORCING FURTHER AIDED ON THE COOL SIDE OF THE FRONT VIA
TIGHTENING HORIZONTAL THERMAL GRADIENT/STRENGTHENING LOW-LEVEL
FRONTOGENETICAL RESPONSE AS STRONG +1040 ARCTIC HIGH OVER THE MID
BEGINS TO BUILD INTO THE REGION. GUIDANCE HAS REALLY TRENDED WETTER
FOR TONIGHT WITH QPF AMOUNTS...ESPECIALLY THE EC AND NAM INDICATING
AS MUCH AS A HALF TO TWO-THIRDS OF AN INCH ACROSS THE SANDHILLS AND
SOUTHERN COASTAL PLAIN...WITH A SHARP CUT-OFF IN PRECIP SE-NW.
TEMPERATURES WILL BE CLOSE TO FREEZING ACROSS THE FAR
NORTH/NORTHWEST(ROXBORO/WINSTON SALEM). CANNOT RULE OUT A BRIEF
MIXTURE OF WINTRY PRECIP...BUT AT THIS TIME QPF AMOUNTS LOOK
LIMITED WITH NO ACCUMULATION EXPECTED AS THIS SYNOPTIC SET-UP
WITH COLD AIR TRYING TO CATCH UP WITH THE PRECIP/MOISTURE RARELY SUPPORTS
MUCH MORE THAN ADVISORY CRITERIA. WILL CONTINUE TO MONITOR.
LOWS RANGING FROM LOWER 30S NORTH TO LOWER 40S SOUTHEAST.
&&
.SHORT TERM /MONDAY THROUGH TUESDAY NIGHT/...
AS OF 320 AM SUNDAY...
MAIN FRONTAL ZONE IS OFFSHORE AND STRETCHING BACK TO THE WEST
SOUTHWEST ACROSS SOUTH CAROLINA MONDAY MORNING. ARCTIC AIR WITH
DEEPER SUB-ZERO TEMPERATURE PROFILES WILL BE EDGING SOUTH IN COLD
AIR ADVECTION SPILLING IN BEHIND THE FRONT. MEANWHILE...
CYCLOGENESIS ALONG THE FRONT OVER SOUTH CAROLINA ASSOCIATED WITH A
SOUTHERN STREAM SHORTWAVE WILL DELAY THE EXIT OF ANAFRONTAL PRECIP
ACROSS THE SOUTHERN HALF OF THE AREA UNTIL LATE MORNING/EARLY
AFTERNOON. WILL HAVE CHANCE TO LIKELY POPS OVER THE EAST AND SOUTH
THROUGH 18Z-ISH...INDICATING A CHANGEOVER FROM RAIN TO A MIX OR ALL
SNOW PROGRESSING SOUTHWARD AS THE MORNING PROGRESSES. THE DRY COLD
AIR WILL BE CHASING THE PRECIP SOUTH RESULTING IN VERY LIGHT AMOUNTS
IN CHANGEOVER ZONE...SO NO ISSUES ARE ANTICIPATED. PRECIP SHOULD
REMAIN ALL RAIN ACROSS THE SOUTH AS IT EXITS IN THE EARLY AFTERNOON.
HIGHS WILL SHOW LITTLE INCLINATION TO CLIMB BEYOND THE UPPER 30S
ACROSS THE NORTH...AND TOP OUT IN THE VERY LOW 40S SOUTH.
SKIES WILL BE CLEARING AS OUR NEXT ARCTIC HIGH MOVES ACROSS THE
SOUTHERN OHIO VALLEY AND MAKES THE USUAL RIGHT TURN DOWN THE
ATLANTIC SEABOARD. RADIATIONAL CONDITIONS WILL BE IMPROVING BY
MORNING AS THE HIGH SETTLES IN WITH CLEAR SKIES AND TEMPS MONDAY
NIGHT WILL BOTTOM OUT FROM 15 TO 20 ACROSS THE NORTH...AND IN THE
LOWER 20S SOUTH. TUESDAY WILL BE DRY...AS WE ARE IN THE ZONE BETWEEN
THE STALLED FRONTAL ZONE TO OUR SOUTH AND BROAD UPPER TROFFING
ACROSS THE EASTERN CONUS WITH MID TO HIGH CLOUDINESS STREAMING
ACROSS THE AREA. ANOTHER 15 DEGREE BELOW NORMAL DAY IS ON TAP
TUESDAY WITH HIGHS WITHIN A DEGREE OR SO EITHER SIDE OF 40. THE
SURFACE HIGH MOVES OFFSHORE AND LIGHT SOUTHERLY FLOW WILL PROVIDE A
LITTLE BUMP INTO THE MID 20S FOR MINS TUESDAY NIGHT.
&&
.LONG TERM /WEDNESDAY THROUGH SATURDAY/...
AS OF 315 AM SUNDAY...
WE CATCH A LITTLE WARMUP ON WEDNESDAY AHEAD OF A DRY REINFORCING
ARCTIC FRONT MOVING THROUGH LATE IN THE DAY. HIGHS WILL BE IN THE
UPPER 40S TO LOWER 50S. CONFIDENCE FALLS OFF AS WE DIG FURTHER INTO
THE EXTENDED PERIOD DUE TO THE MYRIAD OF FEATURES TO CONSIDER FROM
BOTH THE NORTHERN AND SOUTHERN STREAM. A SOUTHERN STREAM SHORT WAVE
NOTED YESTERDAY WILL INDUCE ANOTHER WAVE ON THE STALLED SURFACE
FRONT SOUTH OF THE AREA WEDNESDAY NIGHT...POTENTIALLY WRAPPING SOME
RAIN INTO THE SOUTHEAST LATE WEDNESDAY NIGHT INTO THURSDAY
MORNING...BUT AT THIS POINT THE WAVE LOOKS TO REMAIN WELL SOUTH AND
POPS WILL BE IN THE SLIGHT CHANCE CATEGORY. MINS WEDNESDAY NIGHT
WILL BE MOSTLY IN THE MID 20S...WITH COLD AIR BEHIND THE ARCTIC
FRONT SETTLING IN ON THURSDAY AND LIMITING HIGHS TO THE UPPER 30S TO
LOWER 40S EACH DAY THROUGH SATURDAY. DETAILS FOR LATE WEEK REMAIN
HIGHLY SUSPECT...BUT AT THIS POINT IT WOULD APPEAR THAT OUR BEST
CHANCE FOR PRECIP WOULD BE LATER FRIDAY INTO SATURDAY AS A STRONG
SHORT WAVE IN THE NORTHERN FLOW LIFTS OUT OF THE FILLING EASTERN
TROF AND HAS POTENTIAL TO INTERACT WITH THE SOUTHERLY SUPPRESSED
FRONTAL ZONE.
&&
.AVIATION /12Z SUNDAY THROUGH THURSDAY/...
AS OF 640 AM SUNDAY...
LOW CONFIDENCE WITH RESPECT CEILINGS THIS MORNING AND INTO THE
AFTERNOON.
LIFR VISIBILITIES ASSOCIATED WITH AREA OF DENSE FOG OVER THE
NORTHERN COASTAL PLAIN SHOULD IMPROVE AS BAND OF LIGHT RAIN
CONTINUES TO MOVE EAST ACROSS THE AREA. THIS BAND IS EXPECTED TO
EXIT EASTERN TERMINALS (KRWI AND KFAY)AOA 18Z. CEILINGS COULD PROVE
TO BE QUITE VARIABLE ACROSS THE AREA THIS MORNING. MVFR CEILINGS
HAVE DEVELOPED BEHIND THE RAIN BAND ACROSS THE WESTERN
PIEDMONT...AND HAVE SPREAD THIS TREND EASTWARD THROUGH THE REMAINDER
OF THE MORNING. HOWEVER...SOME GUIDANCE SUGGEST WE COULD SEE
CEILINGS LIFT/SCATTER OUT TO VFR CEILINGS BY THE
AFTERNOON...ESPECIALLY IN THE WESTERN PIEDMONT...OWING TO THE DRIER
WEST-SWLY FLOW ALOFT.
THE ACTUAL SFC COLD FRONT WILL THEN MOVE THROUGH THE AREA BETWEEN 18
TO 03Z MONDAY. AS THE FRONT SINKS SOUTH OF THE AREA...A WAVE OF LOW
PRESSURE IS EXPECTED TO DEVELOP ALONG THE FRONT WHICH WILL CAST RAIN
BACK BACK INTO THE AREA FROM THE SOUTH WITH WIDESPREAD IFR TO MVFR
CEILINGS...LOWEST AT KFAY.
LOOKING BEYOND THE 24 HOUR TAF PERIOD: LOW CONFIDENCE CONTINUES
THROUGH THE EXTENDED PERIOD. SUB-VFR CEILINGS WILL LIKELY LINGER
INTO MONDAY AFTERNOON. COULD ALSO SEE A BRIEF MIXTURE OR CHANGEOVER
FROM RAIN TO SNOW ON MONDAY BEFORE THE PRECIP EXITS THE REGION. VFR
CONDITIONS WILL TRY TO RETURN ON TUESDAY BEFORE A SERIES OF LOW
PRESSURE SYSTEMS TRACKING ACROSS THE SE US BRINGING UNSETTLED
WEATHER THROUGH THE PERIOD.
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...CBL
NEAR TERM...CBL/BLS
SHORT TERM...MLM
LONG TERM...MLM
AVIATION...CBL
AREA FORECAST DISCUSSION...UPDATED
NWS NORMAN OK
549 AM CST SUN FEB 22 2015
.AVIATION...
A STRONG COLD FRONT IS MOVING THROUGH THE AREA WITH GUSTY NORTH
WINDS AND IFR-MVFR CIGS ACROSS NORTHERN OKLAHOMA... WHICH WILL
SPREAD INTO SOUTHERN OKLAHOMA AND NORTH TEXAS AS THE FRONT MOVES
THROUGH. MVFR CIGS AND GUSTY WINDS WILL SPREAD INTO SOUTHERN
OKLAHOMA AND NORTH TEXAS AS THE FRONT PROGRESSES. AREAS OF SNOW
ARE OCCURRING IN NORTHERN AND WESTERN OKLAHOMA WITH MORE
RAIN/SNOW/SLEET EXPECTED TO SPREAD INTO NORTH TEXAS AND SOUTHERN
OKLAHOMA FROM SOUTHWESTERN TEXAS THROUGH THE DAY. WIDESPREAD MVFR
OR LOWER CIGS WILL PERSIST THROUGH THE FORECAST PERIOD.
&&
.PREV DISCUSSION... /ISSUED 442 AM CST SUN FEB 22 2015/
DISCUSSION...
WINTER WEATHER ROUND NUMBER 1 IS UNDERWAY CURRENTLY IN NORTHWEST
OKLAHOMA... BUT NOT WITHOUT COMPLICATIONS. FIRST IS THE RELATIVELY
SLOW ARRIVAL OF THE COLD AIR BRINGING A LATER TRANSITION TO
SNOW... AND SECOND IS THE SPLIT MESOSCALE BANDING THAT HAS
DEVELOPED WITH ONE BAND IN SOUTHWEST KANSAS NEAR DODGE CITY AND
SECOND FROM DUMAS TEXAS TO WATONGA TO GUTHRIE. WITH THE SOUTHERN
BAND PERSISTING AND MOVING EAST... THIS WARRANTS EXPANDING THE
WINTER WEATHER ADVISORY INTO NORTH CENTRAL OKLAHOMA WHERE TRENDS
AND HRRR SUGGEST AN INCH OF SNOW OR SO MAY FALL. ALTHOUGH THE
SPLIT MESOSCALE BANDS HAVE FORMED ON EITHER SIDE OF THE WARNING IN
NORTHWEST OKLAHOMA... WILL NOT DOWNGRADE NOW AS SOME DECENT
SNOWFALL IS STILL POSSIBLE DEPENDING ON HOW THE BANDS EVOLVE
ALTHOUGH RIGHT NOW IT LOOKS LIKE THE HEAVIEST SNOW THIS MORNING
MAY BE NEAR THE ARNETT-TALOGA-WATONGA LINE.
ROUND NUMBER 2 WILL BEGIN TO DEVELOP ACROSS TEXAS AND SPREAD INTO
THE AREA LATER THIS MORNING. COOLING CLOUD TOPS ARE BEING OBSERVED
IN SOUTHWEST TEXAS RIGHT NOW AND RADARS ARE BEGINNING TO DETECT
SOME DEVELOPING ECHOES ACROSS WEST TEXAS. PRECIPITATION WILL
BECOME MORE WIDESPREAD AND THEN SPREAD INTO SOUTHERN PART OF OUR
FORECAST AREA TODAY. AS THE COLD AIR CONTINUES TO SPREAD SOUTH...
PRECIPITATION WILL MIX WITH AND THEN CHANGE TO SNOW THIS AFTERNOON
IN THE SOUTH. AS WAVE NUMBER 2 EXITS TONIGHT... WAVE NUMBER 3
MOVES IN FROM THE WEST AND SPREADS ACROSS THE AREA LATE TONIGHT
AND MONDAY. MODELS SUGGEST MESOSCALE BANDING WILL BE POSSIBLE
AGAIN MAINLY HIGHLIGHTING SOUTHERN OKLAHOMA... BUT AS USUAL THERE
IS SOME UNCERTAINTY ON THE SPECIFIC PLACEMENT OF ANY SMALL SCALE
FEATURES THAT DEVELOP.
RAIN/SNOW WILL BE THE PRIMARY PRECIPITATION TYPES THROUGH THESE
PRECIPITATION EVENTS... BUT SLEET WILL ALSO BE POSSIBLE. IN THE
SOUTH TODAY... THERE MAY BE ENOUGH OF A WARM LAYER TO PARTIALLY
MELT THE SNOW AS IT FALLS BEFORE REFREEZING IN THE COLD LAYER
BELOW. BUT THERE ARE ALSO SUGGESTIONS THAT WE MAY LOSE MOISTURE IN
THE DENDRITIC GROWTH ZONE REGIONS ALOFT AT TIMES THROUGH THIS
EVENT SUGGESTING SUPERCOOLED WATER FREEZING IN THE COLD LAYER.
ALTHOUGH FREEZING RAIN IS NOT COMPLETELY OUT OF THE QUESTION IN
THE SOUTH TODAY... DEPTH OF FORECAST LOW-LEVEL COLD LAYER
INDICATES THAT SLEET IS MORE LIKELY.
THERE WILL BE A BREAK IN THE PRECIPITATION CHANCES TUESDAY AND
WEDNESDAY WITH WARMER TEMPERATURES WEDNESDAY. THEN MORE COLD AIR
ARRIVES AND PRECIPITATION CHANCES REDEVELOP WEDNESDAY
NIGHT/THURSDAY. ALTHOUGH THERE IS AGREEMENT IN THE GENERAL PATTERN
SHIFT... THERE REMAIN DIFFERENCE IN THE MEDIUM RANGE MODELS ON THE
FINER DETAILS WHICH ARE SUFFICIENT ENOUGH TO GIVE LOW CONFIDENCE
IN THE LATER PERIODS OF THE FORECAST.
&&
.PRELIMINARY POINT TEMPS/POPS...
OKLAHOMA CITY OK 32 17 26 18 / 50 40 60 10
HOBART OK 33 17 23 16 / 50 50 60 10
WICHITA FALLS TX 38 21 25 19 / 70 60 70 10
GAGE OK 24 12 23 14 / 90 60 50 10
PONCA CITY OK 26 14 26 16 / 80 20 30 20
DURANT OK 39 22 28 21 / 100 60 80 20
&&
.OUN WATCHES/WARNINGS/ADVISORIES...
OK...WINTER WEATHER ADVISORY UNTIL NOON CST TODAY FOR OKZ007-008-012-
013-018>020.
WINTER WEATHER ADVISORY UNTIL 6 AM CST MONDAY FOR OKZ005-006-011-
014>017.
WINTER STORM WARNING UNTIL 6 AM CST MONDAY FOR OKZ004-009-010.
WINTER WEATHER ADVISORY FROM NOON TODAY TO 6 PM CST MONDAY FOR
OKZ021>048-050>052.
TX...WINTER WEATHER ADVISORY FROM NOON TODAY TO 6 PM CST MONDAY FOR
TXZ083>090.
&&
$$
AREA FORECAST DISCUSSION
NWS NORMAN OK
442 AM CST SUN FEB 22 2015
.DISCUSSION...
WINTER WEATHER ROUND NUMBER 1 IS UNDERWAY CURRENTLY IN NORTHWEST
OKLAHOMA... BUT NOT WITHOUT COMPLICATIONS. FIRST IS THE RELATIVELY
SLOW ARRIVAL OF THE COLD AIR BRINGING A LATER TRANSITION TO
SNOW... AND SECOND IS THE SPLIT MESOSCALE BANDING THAT HAS
DEVELOPED WITH ONE BAND IN SOUTHWEST KANSAS NEAR DODGE CITY AND
SECOND FROM DUMAS TEXAS TO WATONGA TO GUTHRIE. WITH THE SOUTHERN
BAND PERSISTING AND MOVING EAST... THIS WARRANTS EXPANDING THE
WINTER WEATHER ADVISORY INTO NORTH CENTRAL OKLAHOMA WHERE TRENDS
AND HRRR SUGGEST AN INCH OF SNOW OR SO MAY FALL. ALTHOUGH THE
SPLIT MESOSCALE BANDS HAVE FORMED ON EITHER SIDE OF THE WARNING IN
NORTHWEST OKLAHOMA... WILL NOT DOWNGRADE NOW AS SOME DECENT
SNOWFALL IS STILL POSSIBLE DEPENDING ON HOW THE BANDS EVOLVE
ALTHOUGH RIGHT NOW IT LOOKS LIKE THE HEAVIEST SNOW THIS MORNING
MAY BE NEAR THE ARNETT-TALOGA-WATONGA LINE.
ROUND NUMBER 2 WILL BEGIN TO DEVELOP ACROSS TEXAS AND SPREAD INTO
THE AREA LATER THIS MORNING. COOLING CLOUD TOPS ARE BEING OBSERVED
IN SOUTHWEST TEXAS RIGHT NOW AND RADARS ARE BEGINNING TO DETECT
SOME DEVELOPING ECHOES ACROSS WEST TEXAS. PRECIPITATION WILL
BECOME MORE WIDESPREAD AND THEN SPREAD INTO SOUTHERN PART OF OUR
FORECAST AREA TODAY. AS THE COLD AIR CONTINUES TO SPREAD SOUTH...
PRECIPITATION WILL MIX WITH AND THEN CHANGE TO SNOW THIS AFTERNOON
IN THE SOUTH. AS WAVE NUMBER 2 EXITS TONIGHT... WAVE NUMBER 3
MOVES IN FROM THE WEST AND SPREADS ACROSS THE AREA LATE TONIGHT
AND MONDAY. MODELS SUGGEST MESOSCALE BANDING WILL BE POSSIBLE
AGAIN MAINLY HIGHLIGHTING SOUTHERN OKLAHOMA... BUT AS USUAL THERE
IS SOME UNCERTAINTY ON THE SPECIFIC PLACEMENT OF ANY SMALL SCALE
FEATURES THAT DEVELOP.
RAIN/SNOW WILL BE THE PRIMARY PRECIPITATION TYPES THROUGH THESE
PRECIPITATION EVENTS... BUT SLEET WILL ALSO BE POSSIBLE. IN THE
SOUTH TODAY... THERE MAY BE ENOUGH OF A WARM LAYER TO PARTIALLY
MELT THE SNOW AS IT FALLS BEFORE REFREEZING IN THE COLD LAYER
BELOW. BUT THERE ARE ALSO SUGGESTIONS THAT WE MAY LOSE MOISTURE IN
THE DENDRITIC GROWTH ZONE REGIONS ALOFT AT TIMES THROUGH THIS
EVENT SUGGESTING SUPERCOOLED WATER FREEZING IN THE COLD LAYER.
ALTHOUGH FREEZING RAIN IS NOT COMPLETELY OUT OF THE QUESTION IN
THE SOUTH TODAY... DEPTH OF FORECAST LOW-LEVEL COLD LAYER
INDICATES THAT SLEET IS MORE LIKELY.
THERE WILL BE A BREAK IN THE PRECIPITATION CHANCES TUESDAY AND
WEDNESDAY WITH WARMER TEMPERATURES WEDNESDAY. THEN MORE COLD AIR
ARRIVES AND PRECIPITATION CHANCES REDEVELOP WEDNESDAY
NIGHT/THURSDAY. ALTHOUGH THERE IS AGREEMENT IN THE GENERAL PATTERN
SHIFT... THERE REMAIN DIFFERENCE IN THE MEDIUM RANGE MODELS ON THE
FINER DETAILS WHICH ARE SUFFICIENT ENOUGH TO GIVE LOW CONFIDENCE
IN THE LATER PERIODS OF THE FORECAST.
&&
.PRELIMINARY POINT TEMPS/POPS...
OKLAHOMA CITY OK 32 17 26 18 / 50 40 60 10
HOBART OK 33 17 23 16 / 50 50 60 10
WICHITA FALLS TX 38 21 25 19 / 70 60 70 10
GAGE OK 24 12 23 14 / 90 60 50 10
PONCA CITY OK 26 14 26 16 / 80 20 30 20
DURANT OK 39 22 28 21 / 100 60 80 20
&&
.OUN WATCHES/WARNINGS/ADVISORIES...
OK...WINTER WEATHER ADVISORY UNTIL NOON CST TODAY FOR OKZ007-008-012-
013-018>020.
WINTER WEATHER ADVISORY UNTIL 6 AM CST MONDAY FOR OKZ005-006-011-
014>017.
WINTER STORM WARNING UNTIL 6 AM CST MONDAY FOR OKZ004-009-010.
WINTER WEATHER ADVISORY FROM NOON TODAY TO 6 PM CST MONDAY FOR
OKZ021>048-050>052.
TX...WINTER WEATHER ADVISORY FROM NOON TODAY TO 6 PM CST MONDAY FOR
TXZ083>090.
&&
$$
AREA FORECAST DISCUSSION
NWS EL PASO TX/SANTA TERESA NM
512 AM MST SUN FEB 22 2015
.SYNOPSIS...
FOR LOCATIONS EAST OF THE RIO GRAND WE WILL SEE COLDER AIR PUSH
INTO THE REGION THIS EVENING. THE SACRAMENTO MOUNTAINS WILL SEE
SOME MODERATE SNOW AMOUNTS AND WE WILL SEE STRONG GUSTY EAST
WINDS...ESPECIALLY ON THE WEST SIDE OF AREA MOUNTAINS TONIGHT.
MONDAY WE WILL SEE TEMPERATURES A LITTLE BELOW NORMAL. ON TUESDAY
WE WILL SEE A SLIGHT CHANCE FOR PRECIPITATION AND THEN WE WILL SEE
ANOTHER SLIGHT CHANCE FOR PRECIPITATION BY THE END OF THE WEEK.
&&
.DISCUSSION...
LOTS OF WEATHER TO DISCUSS THIS MORNING SO LET`S GET STARTED.
CURRENTLY A DECENT COLD FRONT WAS MAKING IT`S WAY THROUGH THE
EAST PLAINS OF NEW MEXICO HEADED IN OUR DIRECTION. AT THE SAME
TIME A PRETTY STRONG WEST FLOW IS MOVING ACROSS THE AREA IN THE
MIDDLE AND UPPER PART OF THE ATMOSPHERE. THIS WEST FLOW AND THE
COLD FRONT WILL DO BATTLE ACROSS THE AREA ON AND OFF FOR THE NEXT
WEEK. THE WIND SHIFT ASSOCIATED WITH THE FRONT LOOKS TO MAKE IT TO
THE SACRAMENTO MOUNTAINS AROUND NOON...TO THE RIO GRANDE BY THE
AFTERNOON AND MAYBE TO THE CONTINENTAL DIVIDE BY EVENING. OUR
SHORT TERM MODELS STILL HAVE SOME BIG DISAGREEMENTS ON HOW MUCH
COLD AIR WILL PUSH INTO THE REGION. THE GFS KEEPS MOST OF THE COLD
AIR TO THE EAST WHILE THE NAM BRINGS A SHALLOW LAYER OF COLD AIR
WELL INTO HUDSPETH...EL PASO AND OTERO COUNTIES. AS THE WEST FLOW
ALOFT TRIES TO HOLD THE COLD FRONT BACK IT WILL RIDE UP AND OVER
THE FRONTAL SURFACE. THIS WILL HELP CREATE SOME RAIN SHOWERS IN
THE LOWLANDS AND SNOW SHOWERS IN THE MOUNTAINS. SNOW TOTALS RANGE
GREATLY IN MODELS FROM ALMOST 10 INCHES IN THE HRRR TO LESS THAN
AN INCH IN THE NAM. CONSIDERING THE LIMITED AMOUNT OF MOISTURE I
WILL BE LEANING MORE TOWARD THE LOWER TOTALS. PROBABLY SOMETHING
IN THE RANGE OF 2 TO 5 INCHES SHOULD COVER IT. JUST ENOUGH TO
WARRANT A SNOW ADVISORY FOR THE SACRAMENTO MOUNTAINS. THE OTHER
PRECIPITATION QUESTION IS...WILL HUDSPETH COUNTY GET SIGNIFICANT
FREEZING RAIN TONIGHT. AGAIN GOING WITH THE DRIER THEME I THINK WE
COULD SEE SOME LIGHT FREEZING RAIN LATE TONIGHT IN EASTERN
HUDSPETH COUNTY...BUT NOT ENOUGH TO WARRANT A FREEZING RAIN
ADVISORY. IF MORE COLD AIR MOVES IN EARLIER IN THE EVENING WE
COULD SEE SOME ENHANCED ICING WHICH IS SOMETHING LATER SHIFTS WILL
NEED TO MONITOR. FINALLY AS THE EAST PUSH OF COOLER AIR MOVES IN
WE WILL SEE SOME STRONG GUSTY WINDS ON THE WEST SIDE OF AREA
MOUNTAINS EAST OF THE RIO GRANDE. I`VE GONE AHEAD AN ISSUED A WIND
ADVISORY FOR LAS CRUCES AND THE WEST SIDE OF EL PASO...LOCATIONS
THAT GET HIT PRETTY HARD ON A EAST PUSH LIKE THIS.
MONDAY`S HIGH TEMPERATURES ARE A CHALLENGE AS WELL AS THE MODELS
STILL DON`T AGREE ON HOW MUCH COLD AIR WILL LINGER EAST OF THE
RIO GRANDE. WEST OF THE RIVER WE WILL SEE HIGH TEMPERATURES NEAR
NORMAL...BUT EAST OF THE RIVER WE WILL SEE SOME BELOW NORMAL
TEMPERATURES. THE QUESTION IS HOW MUCH BELOW NORMAL. THE NAM IS
GOING 10 TO 12 DEGREES BELOW NORMAL WHILE THE GFS IS GOING AROUND
4 DEGREES BELOW NORMAL. FOR THIS FORECAST PACKAGE I`VE GONE
BETWEEN THOSE FORECASTS BUT LEANED MORE CLOSELY TO THE GFS.
ON TUESDAY AN UPPER LEVEL TROUGH WILL DASH ACROSS THE AREA. THE
MODELS HAVE BEEN GIVING THIS SYSTEM LESS AND LESS MOISTURE TO WORK
WITH FROM ONE RUN TO THE NEXT. I`VE LEFT SOME SLIGHT CHANCE POPS
IN THE FORECAST BUT I`M NOT EXPECTING A LOT OF PRECIPITATION. THE
SYSTEM WILL DRAG SOME COOLER AIR INTO THE REGION. SO HIGHS ON
WEDNESDAY WILL BE NEAR NORMAL. THEN ON THURSDAY WE WILL SEE
ANOTHER SURGE OF COOLER AIR TRY AND PUSH IN FROM THE EAST...BUT
AGAIN THE WESTERLY FLOW ALOFT WILL KEEP MOST OF THE COOLER AIR TO
OUR EAST. PREVIOUS RUNS OF THE EXTENDED MODELS HAD A PRETTY STRONG
SHORT WAVE DROPPING ACROSS THE AREA...BUT CURRENT RUNS OF ALL THE
MODELS HAVE WEAKENED THIS FEATURE. THERE ARE STILL SOME SLIGHT
CHANCE POPS IN THE EXTENDED FORECAST...BUT THOSE MAY HAVE TO BE
PULLED IF THE MODELS STICK TO THE CURRENT SOLUTION.
&&
.AVIATION...VALID 23/12Z-24/12Z
WE WILL SEE MAINLY VFR CONDITIONS FOR MOST OF THE DAY...BUT WE
WILL SEE DETERIORATING CONDITIONS AS WE MOVE INTO THE OVERNIGHT
HOURS. FOR MOST OF THE DAY WE WILL SEE WEST WINDS 23010KT BUT
AROUND 00Z WE WILL SEE A COLD FRONT TRY AND PUSH INTO THE REGION
SO THAT LOCATIONS EAST OF THE CONTINENTAL DIVIDE WILL SEE WINDS
COME AROUND TO THE EAST AND BE RATHER GUSTY...ESPECIALLY ALONG THE
WESTERN SLOPES OF AREA MOUNTAINS. AS THE FRONT MOVES IN WE WILL
SEE LOW CLOUDS DEVELOP ALONG THE FRONT AND WE WILL SEE SOME LIGHT
RAIN OR FREEZING RAIN DEVELOP IN HUDSPETH COUNTY WHILE IN THE
SACRAMENTO MOUNTAINS WE WILL SEE SOME MODERATE TO HEAVY SNOW THIS
EVENING. CEILINGS IN THE MOUNTAINS AND IN HUDSPETH COUNTY COULD
APPROACH IFR CONDITIONS WHILE PLACES FURTHER WEST LIKE KELP AND
KLRU COULD SEE SOME MVFR CEILINGS. FURTHER WEST FOR PLACES LIKE
KDMN AND KTCS WE EXPECT VFR CONDITIONS TO CONTINUE INTO MONDAY
MORNING.
&&
.FIRE WEATHER...
LOTS OF WEATHER TAKING PLACE TODAY AND FOR THE NEXT 7 DAYS. THIS
AFTERNOON A COLD FRONT WILL TRY TO PUSH INTO THE REGION FROM THE
EAST. THE FRONT WILL SWING WINDS STRONGLY AROUND TO THE EAST FOR
LOCATIONS EAST OF THE RIO GRANDE. WE WILL ALSO SEE SOME LIGHT RAIN
IN THE LOWLANDS EAST OF THE RIVER AND SOME MODERATE SNOW AMOUNTS
IN THE SACRAMENTO MOUNTAINS. AFTER MONDAY WE WILL SEE AN UPPER
LEVEL TROUGH APPROACH THE REGION WHICH WILL BRING US A SLIGHT
CHANCE FOR PRECIPITATION TO THE AREA AND A RETURN OF SOME STRONG
GUSTY WINDS ON TUESDAY. WE WILL SEE ANOTHER CHANCE FOR
PRECIPITATION TOWARD THE END OF THE WEEK AS YET ANOTHER UPPER
LEVEL STORM SYSTEM APPROACHES THE REGION. MIN RH`S WILL BE WELL
ABOVE CRITICAL LEVELS TODAY AND MONDAY...BUT WILL APPROACH
CRITICAL LEVELS BY THE TUESDAY. WE WILL BE NEAR RED FLAG
CONDITIONS ON TUESDAY...BUT RIGHT NOW I THINK WE WILL BE JUST A
LITTLE OFF ON BOTH THE WINDS AND RH`S. FOR THE REST OF THE WEEK WE
WILL MIN RH`S STAY ABOVE CRITICAL LEVELS.
&&
.PRELIMINARY POINT TEMPS/POPS...
EL PASO 71 35 59 37 63 / 10 30 10 0 0
SIERRA BLANCA 69 30 50 31 62 / 20 30 20 0 0
LAS CRUCES 69 34 59 34 59 / 10 30 10 0 0
ALAMOGORDO 63 39 54 35 57 / 20 30 20 0 20
CLOUDCROFT 47 31 36 27 37 / 60 70 60 0 20
TRUTH OR CONSEQUENCES 66 36 57 37 57 / 10 30 20 0 20
SILVER CITY 61 36 58 34 51 / 20 30 20 0 20
DEMING 69 38 62 33 59 / 10 20 10 0 0
LORDSBURG 70 41 63 35 57 / 10 20 10 0 0
WEST EL PASO METRO 71 37 59 39 62 / 10 30 10 0 0
DELL CITY 63 31 48 27 60 / 20 40 20 0 0
FORT HANCOCK 71 33 59 36 67 / 20 30 10 0 0
LOMA LINDA 64 29 50 33 57 / 20 30 10 0 0
FABENS 70 35 59 36 64 / 20 30 10 0 0
SANTA TERESA 70 35 59 36 61 / 10 30 10 0 0
WHITE SANDS HQ 69 35 57 35 59 / 10 30 10 0 0
JORNADA RANGE 67 33 59 29 58 / 10 30 10 0 0
HATCH 69 36 62 33 60 / 10 30 10 0 10
COLUMBUS 71 38 63 38 60 / 10 20 10 0 0
OROGRANDE 66 33 55 35 59 / 20 30 20 0 0
MAYHILL 48 23 40 29 46 / 70 70 60 0 20
MESCALERO 53 32 43 28 45 / 50 70 60 0 20
TIMBERON 52 31 43 30 46 / 70 60 40 0 20
WINSTON 60 32 55 33 50 / 20 40 20 0 20
HILLSBORO 64 33 59 34 54 / 10 30 10 0 20
SPACEPORT 66 35 60 32 58 / 10 30 20 0 20
LAKE ROBERTS 59 39 56 33 49 / 20 30 20 0 20
HURLEY 63 35 59 33 53 / 10 30 10 0 10
CLIFF 66 40 63 33 56 / 10 20 10 0 20
MULE CREEK 62 41 61 27 52 / 10 20 10 0 20
FAYWOOD 63 34 59 35 53 / 10 30 10 0 10
ANIMAS 70 42 66 36 60 / 10 20 0 0 0
HACHITA 71 40 65 33 61 / 10 20 10 0 0
ANTELOPE WELLS 69 41 66 36 64 / 10 20 10 0 0
CLOVERDALE 65 43 64 37 59 / 10 20 0 0 0
&&
.EPZ WATCHES/WARNINGS/ADVISORIES...
NM...WIND ADVISORY FROM 8 PM THIS EVENING TO 7 AM MST MONDAY FOR
NMZ411.
WINTER WEATHER ADVISORY FROM 11 AM THIS MORNING TO 11 AM MST
MONDAY FOR NMZ414>416.
TX...WIND ADVISORY FROM 8 PM THIS EVENING TO 7 AM MST MONDAY FOR
TXZ418.
&&
$$
BRICE
AREA FORECAST DISCUSSION
NWS PHOENIX AZ
255 PM MST SUN FEB 22 2015
.SYNOPSIS...
THE STORM TRACK IS FORECAST TO MOVE SOUTH INTO ARIZONA THIS WEEK...
RESULTING IN MUCH COOLER TEMPERATURES. THERE IS A CHANCE OF SHOWERS
MAINLY OVER PORTIONS OF SOUTH CENTRAL ARIZONA MONDAY AND MONDAY
NIGHT. DRY CLOUD FREE WEATHER WILL RETURN WEDNESDAY THROUGH
FRIDAY...WITH ANOTHER STRONG COLD PACIFIC WEATHER SYSTEM EXPECTED
NEXT WEEKEND.
&&
.DISCUSSION...
TONIGHT THROUGH TUESDAY...
A COLD WESTERN CANADIAN TROF CONTINUED TO SLOWLY MOVE AND DEVELOP
SOUTH INTO EAST CENTRAL CALIFORNIA THIS AFTERNOON. MODELS CONTINUE
TO RETROGRADE THIS TROF SLIGHTLY MORE TONIGHT...THEN MOVE IT ACROSS
UT AND PARTS OF NORTHERN AZ MONDAY AND TUESDAY.
ALL ALONG MODELS HAVE BEEN STRUGGLING WITH THE AMOUNT OF SYSTEM
MOISTURE ALONG THE FRONTAL ZONE...ESPECIALLY AS IT MOVES ACROSS OUR
FORECAST AREA...SOUTHEAST CA TO SOUTH CENTRAL AZ SUNDAY NIGHT AND
MONDAY. MORNING WEATHER BALLOON SOUNDINGS DID SHOWED COLD 700 MB
TEMPS HAD MOVED OFFSHORE NORTHERN CA LAST NIGHT...AND HAS SPUN UP
SOME BOUNDARY LAYER MOISTURE CLEARLY SEEN IN SATELLITE IMAGERY NEAR
SANTA BARBARA THIS AFTERNOON.
ALSO INTERESTING TO NOTE WAS THE HIGHLY DIFFERENT GFS AND EUROPEAN
MODEL 850 MB DEWPOINT INITIAL ANALYSIS 400 MILES SOUTHWEST OF SAN
DIEGO COMPARED WITH MORNING PRECIP WATER IMAGERY (PWI). THE GFS
MODEL APPEARED WAY OVERDONE OR INITIALIZED TOO MUCH MOISTURE IN THIS
AREA WHICH IS A CONCERN SINCE EVENTUALLY SOME OF THIS MOISTURE WILL
MOVE INTO AZ FROM THIS DIRECTION.
THE ABOVE ASIDE...MODEL RUNS HAVE REPEATEDLY FORECAST MOST MOISTURE
TO BE CONFINED TO THE BOUNDARY LAYER ACROSS PARTS OF SOUTHWEST AND
SOUTH CENTRAL AZ MONDAY/MONDAY NIGHT...MEANING IN THE WARM SECTOR.
RECENT MODEL GUIDANCE HAS ALSO RESPONDED WITH CONSISTENT 50 PERCENT
MOS PRECIP PROBABILITIES (PP) FOR PHX AND VCNTY. SINCE LOW LEVEL
WINDS ALONG THE FRONTAL ZONE WILL BE IN THE 20-25 KT RANGE FROM THE
SOUTHWEST...WE COULD SEE A CHANCE OF WARM RAIN OR COLLISION
COALESCENCE RAINS ESPECIALLY ALONG AND NEAR IN THE UPSLOPE AREAS OF
LA PAZ...MARICOPA...AND SOUTHERN GILA COUNTIES. THEREFORE THE
HIGHEST PRECIP PROBABILITIES WILL BE ON THE SOUTH CENTRAL
DESERTS/MOUNTAINS MONDAY AND MONDAY NIGHT. A SLIGHT CHANCE OF PRECIP
WILL LINGER OVER MOUNTAINOUS SOUTHERN GILA COUNTY ZONE 24 ON TUESDAY
AS THE SYSTEM MOVES BODILY INTO NEW MEXICO BY TUESDAY AFTERNOON.
WEDNESDAY THROUGH FRIDAY...
DRY NORTHWEST FLOW ALOFT WITH A FEW WEAK EMBEDDED DISTURBANCES WED
AND THU WILL RESULT IN PARTLY CLOUDY SKIES...AND KEEP TEMPERATURES
NEAR NORMAL.
SATURDAY AND SUNDAY...
THERE APPEARS TO BE A MAJOR WAVE PATTERN RE-ADJUSTMENT ACROSS THE
PACIFIC THIS WEEK WITH MOST PROMINENT LARGE WAVES RETROGRADING. THIS
MEANS MORE TROF RETROGRESSION OVER THE WESTERN STATES...WITH STORM
TRAJECTORIES OVER THE PACIFIC FOR INCREASED MOISTURE/PRECIP IN
ARIZONA LATE SATURDAY INTO SUNDAY.
&&
.AVIATION...
SOUTH-CENTRAL ARIZONA INCLUDING KPHX...KIWA AND KSDL...
LOWER LEVEL CLOUDINESS HAS BEEN SLOW TO MATERIALIZE AS IT APPEARS
MODELS OVERESTIMATED AMOUNT OF MOISTURE AVAILABLE TO SPILL OVER THE
BAJA MOUNTAINS. RAP SOUNDINGS APPEAR TO HAVE A BETTER HANDLE ON THE
SITUATION THAN NAM AND GFS. THUS TAFS WERE AMENDED TO REFLECT
TRENDS. OF NOTE...SOME ISOLATED CUMULUS HAS STARTED TO DEVELOP OVER
SOME LOCAL MOUNTAINS SO EXPECT AT LEAST SOME STRATOCUMULUS
DEVELOPMENT DURING THE DAY TODAY AND THERE IS STILL SOME POTENTIAL
FOR CIGS IN THE FL050-070 RANGE. OTHERWISE...CLOUD DECKS WILL
GENERALLY BE ABOVE FL100-120 THROUGH THE EVENING. SURFACE WINDS
SHOULD FAVOR SOUTHERLY COMPONENT AND BE SLOW TO TURN
WESTERLY...THOUGH SOUTHWESTERLY WILL PREVAIL ABOVE THE SURFACE
THROUGH A VERY DEEP LAYER. AFTER 06Z...LOWER LEVEL CIGS BECOME MORE
LIKELY AS A FRONTAL BAND APPROACHES AND EVENTUALLY MOVES THROUGH
MONDAY. ISOLATED TO SCATTERED LIGHT SHOWERS WILL BE LIMITED
PRIMARILY TO GILA COUNTY AND NORTHERN MARICOPA COUNTY AFTER
12Z...MORE WIDESPREAD FURTHER NORTH.
SOUTHEAST CALIFORNIA AND SOUTHWEST ARIZONA INCLUDING KIPL AND KBLH...
SURFACE WINDS OVER SOUTHEAST CALIFORNIA HAVE WEAKENED QUITE A BIT
COMPARED TO LAST NIGHT ANTICIPATE SOME STRENGTHENING TOWARD LATE
AFTERNOON AND ESPECIALLY THIS EVENING. MEANWHILE OVER SOUTHWEST
ARIZONA SOUTH-SOUTHWESTERLY WINDS WILL PICK UP THIS AFTERNOON
REMAINING STRONGER THAN NORMAL OVERNIGHT. AS FOR
CLOUDINESS...ANTICIPATE FEW-SCT STRATOCUMULUS DEVELOPING THIS
AFTERNOON WITH CIGS OF FL050-070 DEVELOPING AFTER 06Z AS A FRONTAL
BAND APPROACHES AND MOVES THROUGH OVERNIGHT. ANTICIPATE ONLY
ISOLATED SHOWERS...MAINLY LA PAZ AND EASTERN RIVERSIDE COUNTIES.
AVIATION DISCUSSION NOT UPDATED FOR AMENDED TAFS.
&&
.FIRE WEATHER...
TUESDAY THROUGH SATURDAY...
UPPER LOW PRESSURE FEATURE WILL CONTINUE TO SLOWLY ROTATE THROUGH
SOUTHERN PORTIONS OF THE GREAT BASIN...CA AND AZ TUESDAY AND
TRANSITION EAST OF THE AREA WEDNESDAY. MOST NOTICEABLE IMPACT FOR
THE SOUTH-CENTRAL AZ AND SOUTHEAST CA DISTRICTS WILL BE INCREASING
WINDS...WITH LOCALLY STRONGER WINDS OVER AREA RIDGETOPS AND MOUNTAIN
GAPS/PASSES. ANY LINGERING RAIN SHOWER ACTIVITY WILL TRANSITION INTO
PORTIONS OF SOUTHERN GILA COUNTY AND EASTERN AZ FOR TUESDAY. MUCH
COOLER TEMPERATURES...IN COMPARISON TO VALUES OBSERVED OVER THE LAST
FEW WEEKS...WILL SETTLE INTO THE AREA FOR THE REMAINDER OF THE WEEK.
THE UPPER LEVEL STORM PATTERN WILL BECOME MORE ACTIVE ACROSS THE
WESTERN U.S....WITH A SERIES OF WEATHER DISTURBANCES PASSING BY OR
THROUGH THE SOUTHWEST FOR THE REST OF THE WEEK AND COMING WEEKEND.
DEWPOINTS AND HUMIDITIES WILL BEGIN TO DRY TOWARDS THE END OF THE
WEEK WITH SOME ON AND OFF LOCAL BREEZINESS IN RESPONSE TO THE
PASSING WEATHER SYSTEMS.
&&
.PSR WATCHES/WARNINGS/ADVISORIES...
AZ...NONE.
CA...NONE.
&&
$$
VISIT US ON FACEBOOK...TWITTER...AND AT WEATHER.GOV/PHOENIX
DISCUSSION...VASQUEZ
AVIATION...AJ
FIRE WEATHER...NOLTE
AREA FORECAST DISCUSSION...UPDATE
NWS PHOENIX AZ
950 AM MST SUN FEB 22 2015
.UPDATE...
UPDATED AVIATION SECTION.
&&
.SYNOPSIS...
THE STORM TRACK IS FORECAST TO MOVE SLOWLY SOUTH TOWARD ARIZONA THIS
WEEK. THIS WILL RESULT IN VARIABLE CLOUDINESS AND A COOLING TREND. A
COLD FRONT IS FORECAST TO MOVE INTO NORTHERN ARIZONA MONDAY AND
TUESDAY...WITH MUCH COOLER AFTERNOON TEMPERATURES...AND A CHANCE OF
SHOWERS IN SOUTH CENTRAL ARIZONA. RELATIVELY COOL TEMPERATURES WILL
CONTINUE INTO THE WEEKEND.
&&
.DISCUSSION...
A COLD WESTERN CANADIAN TROF CONTINUED TO SLOWLY MOVE AND DEVELOP
SOUTH OVERNIGHT...AND WAS CENTERED IN FAR NORTHEAST NEVADA AT 500 MB
THIS MORNING. MODEL FORECASTS CONTINUE TO RETROGRADE THIS TROF
TOWARD EAST CENTRAL CA TODAY...THEN MOVE IT ACROSS UT AND PARTS OF
NORTHERN AZ MONDAY AND TUESDAY.
ALL ALONG MODELS HAVE BEEN STRUGGLING WITH THE AMOUNT OF SYSTEM
MOISTURE ALONG THE FRONTAL ZONE...ESPECIALLY AS IT MOVES ACROSS OUR
FORECAST AREA...SOUTHEAST CA TO SOUTH CENTRAL AZ SUNDAY NIGHT AND
MONDAY...SINCE ITS MAINLY A CONTINENTAL OR OVERLAND MOVING TROF.
MORNING WEATHER BALLOON SOUNDINGS SHOWED SOME COLD 700 MB
TEMPERATURES HAD MOVED OFFSHORE NORTHERN CA OVERNIGHT...AND A
SPIN-UP OF BOUNDARY LAYER MOISTURE WAS SEEN IN IR SATELLITE IMAGERY
OFFSHORE SAN FRANCISCO FROM ROUGH WIND DRIVEN SEAS.
ANOTHER INTERESTING THING TO NOTE WAS THE HIGHLY DIFFERENT GFS AND
EUROPEAN MODEL 6-12 HR 850 MB DEWPOINT FORECASTS 400 MILES SOUTHWEST
OF SAN DIEGO COMPARED WITH MORNING PRECIP WATER IMAGERY (PWI). THE
GFS MODEL APPEARED WAY OVERDONE OR FORECASTS TOO MUCH MOISTURE IN
THIS AREA....SINCE EVENTUALLY SOME OF THE MOISTURE FOR MONDAY WILL
ORIGINATE FROM THIS DIRECTION.
THE ABOVE ASIDE...MODELS ALL ALONG HAVE FORECAST ALL THE MOISTURE TO
BE IN THE BOUNDARY LAYER WITH THE FRONTAL ZONE ACROSS PARTS OF
SOUTHWEST AND SOUTH CENTRAL AZ FOR MONDAY...MEANING IN THE WARM
SECTOR BELOW 800 MB. RECENT MOS GUIDANCE HAS ALSO RESPONDED TO THE
INCREASE IN BOUNDARY LAYER MOISTURE WITH CONSISTENT 50 PERCENT
PRECIP PROBABILITIES (PP) ON MON FOR PHX AND VCNTY...AND PP WAS
RAISED ON PREVIOUS SHIFTS FOR PARTS OF SOUTHWEST AND SOUTH CENTRAL
AZ. SINCE LOW LEVEL WINDS ALONG THE FRONTAL ZONE WILL BE IN THE
20-25 KT RANGE FROM THE SOUTHWEST...I GUESS WE COULD SEE SOME SPOTTY
WARM RAIN OR COLLISION COALESCENCE RAINS...ESPECIALLY IN THE UPSLOPE
AREAS MON AND MON NIGHT.
THEREFORE AGREE WITH THE INCREASE IN PP ON THE DESERTS FOR MON.
FORECASTS THEREFORE LOOK OK. NO UPDATES PLANNED. PREVIOUS DISCUSSION
BELOW STILL APPLIES.
.PREVIOUS DISCUSSION...538 AM MST...
EARLY THIS MORNING A RATHER DEEP AND COLD UPPER LEVEL LOW PRESSURE
SYSTEM CONTINUED TO TAKE SHAPE TO OUR NORTHWEST...OVER MUCH OF NRN
CA AND NEVADA. THE DEVELOPING LOW WAS CLEARLY EVIDENT ON VAPOR
IMAGERY AND LATEST PLOTS DEPICTED 40-80M H5 HEIGHT FALLS OVER
PORTIONS OF WESTERN NV AND NRN CA...INDICATIVE OF THE DEVELOPING
SYSTEM. VARIABLE AMOUNTS OF MID/HI LEVEL MOISTURE CONTINUED TO
STREAM INTO ARIZONA FROM THE SOUTHWEST AS SEEN IN IR IMAGERY...WITH
SOME LOWER LEVEL MOISTURE BEING PULLED UP INTO SERN AZ. LATEST RADAR
SHOWED WEAK ECHO DEVELOPING ACROSS SERN AZ...SOME OF WHICH MAY BE
VIRGA. AT THE SAME TIME...BLENDED TOTAL PWAT IMAGERY SHOWED VALUES
IN EXCESS OF ONE INCH LURKING SOUTH OF THE AZ BORDER...MAINLY OVER
THE CENTRAL/SRN PORTION OF THE GULF OF CA....EXTENDING WESTWARD OFF
THE CENTRAL BAJA CA COAST. SOME OF THIS MOISTURE WILL BE TAPPED BY
THE DEVELOPING LOW...AND WILL AID IN PRECIP DEVELOPMENT OVER THE
CENTRAL DESERTS MONDAY AND MONDAY NIGHT. OVERALL FOR TODAY...WHILE
THE LOW SPINS UP TO OUR NORTHWEST...DYNAMICS AND MOISTURE WILL BE A
BIT LIMITED SO WE DO NOT EXPECT MUCH IN TERMS OF SHOWERS OVER OUR
LOWER DESERTS. THERE WILL BE A SLIGHT CHANCE FOR SHOWERS DEVELOPING
OVER THE HIGHER TERRAIN OF JOSHUA TREE NP LATER TODAY BUT MAINLY WE
WILL SEE PARTLY TO MOSTLY CLOUDY SKIES DEVELOP AS LOW LEVEL MOISTURE
CONTINUES TO INCREASE.
GUIDANCE REMAINS CONSISTENT IN HANDLING THE TIMING AND TRACK OF THE
LOW TO OUR NORTHWEST...AND CONTINUES TO CALL FOR IT TO MOVE EASTWARD
AND ACROSS THE STATE MONDAY INTO TUESDAY BRINGING WIDESPREAD SHOWERS
TO NORTHERN AZ...AND SCATTERED SHOWERS TO THE SOUTH CENTRAL ARIZONA.
THE LOW AND ITS ASSOCIATED UPPER JET HAVE BEEN TRENDING A BIT
FURTHER SOUTH OVER THE PAST FEW MODEL RUNS...AND MOISTURE CONTINUES
TO INCREASE AND AS SUCH CHANCES FOR PRECIP OVER THE DESERTS HAVE
BEEN RISING OVER THE PAST COUPLE OF DAYS. LATEST MRA GUIDANCE KEEPS
POPS IN THE 50 PERCENT BALLPARK FOR THE CENTRAL DESERTS ON
MONDAY...AND EARLIER MEX/MRA RUNS WERE AS HIGH AS 70 PERCENT. BEST
WINDOW FOR RAINFALL WITH HIS EVENT WILL BE TONIGHT FOR THE WESTERN
DESERTS...AND MONDAY/MONDAY EVENING FOR SOUTH CENTRAL AZ. WE HAVE
RAISED POPS AGAIN...INTO THE LIKELY CATEGORY ACROSS FAR NRN MARICOPA
COUNTY...AND INTO THE GOOD CHANCE CATEGORY OVER MUCH SOUTH CENTRAL
AZ. LATEST SREF/GEFS/NAEFS ENSEMBLE MEMBERS SUPPORT THIS INCREASING
POP TREND WITH THIS SYSTEM. GIVEN THE CLOUDS AND SHOWERS EXPECTED
MONDAY HIGH TEMPS WILL DROP OFF QUITE A BIT WITH HIGHS LOWERING INTO
THE MID TO UPPER 60S OVER MUCH OF THE CENTRAL DESERTS INCLUDING THE
GREATER PHOENIX AREA. A CONTINUED CHANCE FOR SHOWERS WILL BE IN
EFFECT FROM PHOENIX EAST MONDAY NIGHT AS THE LOW STARTS TO EJECT AND
MOVE EAST ACROSS ARIZONA...AND A STRONG 130KT UPPER JET ON THE
SOUTHEAST FLANK OF THE LOW WILL HELP TO QUICKLY EJECT THIS SYSTEM TO
OUR EAST DURING THE DAY ON TUESDAY. A LINGERING SLIGHT CHANCE FOR
SHOWERS IS EXPECTED TUESDAY OVER THE HIGHER TERRAIN EAST OF PHOENIX
BUT WE SHOULD SEE QUITE A BIT OF CLEARING OVER THE DESERTS WEST OF
PHOENIX AS STRONG SUBSIDENCE ALOFT OVERSPREADS THE AREA. TEMPS WILL
STAY ON THE COOL SIDE AGAIN TUESDAY...WITH MOST OF THE CENTRAL
DESERTS STAYING IN THE MID TO UPPER 60S.
FOR WEDNESDAY THROUGH FRIDAY...BOTH THE GFS AND ECMWF KEEP A
RELATIVELY DRY NORTHWEST FLOW ALOFT IN PLACE OVER THE DESERT
SOUTHWEST...AS THEY MIGRATE THE UPPER RIDGE OFF THE WEST COAST AND
KEEP BROAD TROFFING IN PLACE OVER MOST OF THE CONUS. A SERIES OF
DISTURBANCES IS FORECAST TO MOVE SOUTHEASTWARD AND THROUGH THE NW
FLOW...BUT THEY SHOULD BE DRY SYSTEMS AND WE WILL KEEP POPS IN THE
SINGLE DIGITS EVERYWHERE. THERE ARE TIMING DIFFERENCES BETWEEN THE
MODELS WITH THESE SYSTEMS BUT THEY SHOULD NOT REALLY AFFECT OUR
SENSIBLE WEATHER THROUGH THE 3 DAY PERIOD. TEMPS WILL CLIMB A FEW
DEGREES AND BACK TO NEAR SEASONAL NORMAL VALUES.
FOR THE WEEKEND...MODELS HAVE BEEN STRUGGLING WITH THE EVOLUTION OF
THE WEATHER PATTERN OVER THE PAST SEVERAL RUNS...AND ENSEMBLE
MEMBERS FROM THE GEFS HAVE BEEN ALL OVER THE PLACE. STILL...THE
LATEST 00Z RUN FROM BOTH THE GFS AND ECMWF SUGGEST THAT ANOTHER DEEP
TROF WILL SET UP OVER THE WESTERN CONUS AND BRING ANOTHER THREAT FOR
SHOWERS TO THE DESERTS. AS SUCH...WE RAISED POPS MOSTLY INTO THE
SLIGHT CHANCE CATEGORY OVER MOST OF THE AREA FOR THE WEEKEND AND
STARTED A DECREASING TEMP TREND. LATEST MRA POPS FOR PHOENIX CALLED
FOR A NEARLY 90 PERCENT CHANCE OF RAIN SATURDAY NIGHT. THIS SEEMS
VERY EXTREME AND AS SUCH WILL NOT TREND POPS NEARLY THAT HIGH.
BUT...IT IS AN INTERESTING DEVELOPMENT...AS MRA NUMBERS ARE RARELY
THAT HIGH AT THE END OF THE EXTENDED FORECAST PERIOD.
&&
.AVIATION...
SOUTH-CENTRAL ARIZONA INCLUDING KPHX...KIWA AND KSDL...
LOWER LEVEL CLOUDINESS HAS BEEN SLOW TO MATERIALIZE AS IT APPEARS
MODELS OVERESTIMATED AMOUNT OF MOISTURE AVAILABLE TO SPILL OVER THE
BAJA MOUNTAINS. RAP SOUNDINGS APPEAR TO HAVE A BETTER HANDLE ON THE
SITUATION THAN NAM AND GFS. THUS TAFS WERE AMENDED TO REFLECT
TRENDS. OF NOTE...SOME ISOLATED CUMULUS HAS STARTED TO DEVELOP OVER
SOME LOCAL MOUNTAINS SO EXPECT AT LEAST SOME STRATOCUMULUS
DEVELOPMENT DURING THE DAY TODAY AND THERE IS STILL SOME POTENTIAL
FOR CIGS IN THE FL050-070 RANGE. OTHERWISE...CLOUD DECKS WILL
GENERALLY BE ABOVE FL100-120 THROUGH THE EVENING. SURFACE WINDS
SHOULD FAVOR SOUTHERLY COMPONENT AND BE SLOW TO TURN
WESTERLY...THOUGH SOUTHWESTERLY WILL PREVAIL ABOVE THE SURFACE
THROUGH A VERY DEEP LAYER. AFTER 06Z...LOWER LEVEL CIGS BECOME MORE
LIKELY AS A FRONTAL BAND APPROACHES AND EVENTUALLY MOVES THROUGH
MONDAY. ISOLATED TO SCATTERED LIGHT SHOWERS WILL BE LIMITED
PRIMARILY TO GILA COUNTY AND NORTHERN MARICOPA COUNTY AFTER
12Z...MORE WIDESPREAD FURTHER NORTH.
SOUTHEAST CALIFORNIA AND SOUTHWEST ARIZONA INCLUDING KIPL AND KBLH...
SURFACE WINDS OVER SOUTHEAST CALIFORNIA HAVE WEAKENED QUITE A BIT
COMPARED TO LAST NIGHT ANTICIPATE SOME STRENGTHENING TOWARD LATE
AFTERNOON AND ESPECIALLY THIS EVENING. MEANWHILE OVER SOUTHWEST
ARIZONA SOUTH-SOUTHWESTERLY WINDS WILL PICK UP THIS AFTERNOON
REMAINING STRONGER THAN NORMAL OVERNIGHT. AS FOR
CLOUDINESS...ANTICIPATE FEW-SCT STRATOCUMULUS DEVELOPING THIS
AFTERNOON WITH CIGS OF FL050-070 DEVELOPING AFTER 06Z AS A FRONTAL
BAND APPROACHES AND MOVES THROUGH OVERNIGHT. ANTICIPATE ONLY
ISOLATED SHOWERS...MAINLY LA PAZ AND EASTERN RIVERSIDE COUNTIES.
AVIATION DISCUSSION NOT UPDATED FOR AMENDED TAFS.
&&
.FIRE WEATHER...
TUESDAY THROUGH SATURDAY...
UPPER LOW PRESSURE FEATURE WILL CONTINUE TO SLOWLY ROTATE THROUGH
SOUTHERN PORTIONS OF THE GREAT BASIN...CA AND AZ TUESDAY AND
TRANSITION EAST OF THE AREA WEDNESDAY. MOST NOTICEABLE IMPACT FOR
THE SOUTH-CENTRAL AZ AND SOUTHEAST CA DISTRICTS WILL BE INCREASING
WINDS...WITH LOCALLY STRONGER WINDS OVER AREA RIDGETOPS AND MOUNTAIN
GAPS/PASSES. ANY LINGERING RAIN SHOWER ACTIVITY WILL TRANSITION INTO
PORTIONS OF SOUTHERN GILA COUNTY AND EASTERN AZ FOR TUESDAY. MUCH
COOLER TEMPERATURES...IN COMPARISON TO VALUES OBSERVED OVER THE LAST
FEW WEEKS...WILL SETTLE INTO THE AREA FOR THE REMAINDER OF THE WEEK.
THE UPPER LEVEL STORM PATTERN WILL BECOME MORE ACTIVE ACROSS THE
WESTERN U.S....WITH A SERIES OF WEATHER DISTURBANCES PASSING BY OR
THROUGH THE SOUTHWEST FOR THE REST OF THE WEEK AND COMING WEEKEND.
DEWPOINTS AND HUMIDITIES WILL BEGIN TO DRY TOWARDS THE END OF THE
WEEK WITH SOME ON AND OFF LOCAL BREEZINESS IN RESPONSE TO THE
PASSING WEATHER SYSTEMS.
&&
.PSR WATCHES/WARNINGS/ADVISORIES...
AZ...NONE.
CA...NONE.
&&
$$
VISIT US ON FACEBOOK...TWITTER...AND AT WEATHER.GOV/PHOENIX
DISCUSSION...VASQUEZ/CB
AVIATION...AJ
FIRE WEATHER...NOLTE
AREA FORECAST DISCUSSION
NWS RENO NV
1002 AM PST SUN FEB 22 2015
.UPDATE...
LIGHT SNOW SHOWERS CONTINUE ACROSS PORTIONS OF MONO COUNTY WITH
AREA WEBCAMS SHOWING A LIGHT SNOW THROUGH LEE VINING AND MAMMOTH
WITH A THIN COATING OF SNOW ACROSS PORTIONS OF HWY 395 MAINLY
THROUGH CONWAY SUMMIT. AREAS OF BLOWING DUST COMING OFF THE
CARSON SINK ARE STARTING TO DEVELOP NEAR FALLON THIS MORNING WITH
VISIBILITY CURRENTLY DROPPING BELOW 2 MILES.
MADE SOME MINOR ADJUSTMENTS TO THE CLOUD COVER THROUGH THIS
AFTERNOON WITH MOSTLY CLOUDY CONDITIONS FROM MONO-MINERAL COUNTY
EXTENDING NORTH THROUGH THE TAHOE BASIN AND FAR WESTERN NEVADA. LIGHT
SNOW SHOWERS OR FLURRIES WILL CONTINUE ACROSS TAHOE THIS AFTERNOON
AS A LOW STRATOCUMULUS DECK SETTLES OVER THE RELATIVELY WARMER
LAKE SURFACE. ALTHOUGH NO ACCUMULATIONS ARE EXPECTED ACROSS THE
TAHOE BASIN THIS AFTERNOON COULD SEE SOME VERY LOCALIZED AREAS
WITH A DUSTING OF SNOW FROM NARROW LAKE ENHANCEMENT BANDS.
MAIN CONCENTRATION OF SNOW SHOWERS WILL REMAIN ACROSS MONO COUNTY
WHERE 1-3" OF ADDITIONAL SNOW ACCUMULATION IS POSSIBLE. TRAVEL
IMPACTS SHOULD BE MAINLY WET ROAD SURFACES AND REDUCED VISIBILITY
IN SHOWER ACTIVITY AS SNOWFALL IS HAVING A HARD TIME STICKING WITH
THE DAYTIME HEATING. SHOWERS WILL CONTINUE INTO EARLY MONDAY
MORNING BEFORE DIMINISHING BY THE EARLY AFTERNOON. FUENTES
&&
.PREVIOUS DISCUSSION... /ISSUED 258 AM PST SUN FEB 22 2015/
SYNOPSIS...
A STRONG FRONT WILL MOVE THROUGH THE REGION EARLY THIS MORNING
WITH MUCH COLDER TEMPERATURES TODAY AND MONDAY. THERE WILL BE A
PERIOD OF LIGHT SNOW TODAY INTO MONDAY IN THE SIERRA SOUTH OF
HIGHWAY 50, WITH A CHANCE OF SHOWERS ELSEWHERE SOUTH OF HIGHWAY
50. AREAS OF BLOWING DUST MAY OCCUR NORTH OF HIGHWAY 50 AS WINDS
BECOME BREEZY. TEMPERATURES WILL REBOUND TO AROUND AVERAGE BY THE
MIDDLE OF NEXT WEEK WITH NO PRECIPITATION TUESDAY THROUGH
THURSDAY.
SHORT TERM...
WINDS ARE INCREASING OUT OF THE NORTH AS A STRONG COLD FRONT DROPS
INTO CENTRAL AND SOUTHERN NEVADA THIS MORNING. THERE HAVE BEEN
SOME ISOLATED REPORTS OF SOME SNOW FLURRIES MAINLY IN UPSLOPE
LOCATIONS AROUND LAKE TAHOE. EXPECT VERY ISOLATED SNOW SHOWERS TO
CONTINUE AROUND LAKE TAHOE BEFORE FORCING SHIFTS SOUTH BY MID
MORNING.
SOME MODERATE CHANGES WERE MADE TO THE PREVIOUS FORECAST MAINLY
CONCERNING WINDS AND THE POTENTIAL FOR BLOWING DUST. GENERALLY
INCREASED SUSTAINED WIND SPEEDS TO AROUND 20 MPH FOR LOCATIONS
AROUND AND NORTH OF INTERSTATE 80 INCLUDING THE RENO METRO AREA.
ALSO INCREASED GUSTS MARGINALLY TO AROUND 35 MPH IN THE RENO METRO
AREA AND TO AROUND 40 MPH FOR CHURCHILL AND PERSHING COUNTIES.
CONSIDERING THE AMOUNT OF DUST LOFTED SATURDAY, HAVE ADDED AREAS
OF BLOWING DUST FOR MUCH OF THE FORECAST REGION. THIS INCLUDES
LOCATIONS FROM NORTHERN WASHOE COUNTY THROUGH THE SUSANVILLE AND
RENO METRO AREAS CONTINUING SOUTH AND EAST THROUGH CHURCHILL,
PERSHING, AND MINERAL COUNTIES. FALLON AND OTHER LOCATIONS
DOWNWIND OF DRY LAKE BEDS CAN EXPECT PERIODS OF VISIBILITY
RESTRICTIONS DOWN TO 1 MILE WITH THE POTENTIAL FOR LOCAL
RESTRICTIONS TO LESS THAN 1 MILE BRIEFLY. RENO AND SPANISH SPRINGS
WILL LIKELY SEE BLOWING DUST OUT OF THE SMOKE CREEK DESERT. THERE
COULD BE VISIBILITY RESTRICTIONS DOWN TO 3 MILES AND LOCALLY TO 1
MILE AT TIMES. WINDS FALL OFF BY MONDAY MORNING AND DUST SHOULD
SETTLE QUICKLY.
OTHERWISE, NO OTHER MAJOR CHANGES. STILL EXPECT THE BEST
PRECIPITATION CHANCES PRIMARILY SOUTH OF HIGHWAY 50 IN THE SIERRA
THIS AFTERNOON SPREADING EASTWARD INTO SOUTHERN LYON AND MINERAL
COUNTIES BY LATE THIS EVENING. IN GENERAL, LOCATIONS IN MONO
COUNTY COULD SEE UP TO 2 INCHES WITH 2 TO 4 INCHES ABOVE 7000
FEET. LOCAL TOTALS IN UPSLOPE AREAS COULD SEE ANOTHER INCH OR SO.
ADDITIONALLY, THERE ARE SOME INDICATIONS THAT LEE VINING AND
NEARBY HIGHWAY 395 COULD SEE SOME MORE SNOW ACCUMULATION DUE TO LAKE
ENHANCEMENT OFF OF MONO LAKE. THE HRRR MODEL DOES SHOW A PLUME OF
SNOW DEVELOPING JUST EAST OF LEE VINING ALONG HIGHWAY 395 AND THE
LONG VALLEY CRATER RIM. RESIDENTS AND TRAVELERS SHOULD ANTICIPATE
PERIODS OF INCREASED PRECIPITATION RATES IN THE VICINITY OF MONO
LAKE.
PRECIPITATION EXITS THE FORECAST AREA AS LOW PRESSURE DROPS
FARTHER SOUTH INTO SOUTHERN NEVADA MONDAY AFTERNOON INTO TUESDAY.
SOME LINGERING VERY ISOLATED SNOW SHOWERS WILL BE POSSIBLE OVER
THE HIGHER TERRAIN IN MONO COUNTY, BUT WILL TAPER QUICKLY MONDAY
EVENING AS HIGH PRESSURE AND VERY DRY AIR MOVE IN TUESDAY. BOYD
LONG TERM...WEDNESDAY THROUGH SATURDAY...
RIDGE OF HIGH PRESSURE WILL RETROGRADE WESTWARD TO NEAR 140W,
KEEPING NORTHWEST FLOW OVER THE WESTERN STATES. A WEAK SHORTWAVE
WILL DROP THROUGH THE GREAT BASIN ON WEDNESDAY, WHICH WILL MAINLY
SERVE TO HOLD TEMPERATURES CLOSE TO NORMAL. DRY AND COOL NORTHWEST
FLOW WILL REMAIN OVER THE REGION INTO FRIDAY.
MODELS ARE STILL FLIP-FLOPPING IN THE EXTENDED FORECAST PERIOD,
SHOWING QUITE A DIFFERENT SOLUTION FOR NEXT WEEKEND THAN YESTERDAY.
LATEST 00Z RUNS OF THE ECMWF AND GFS ARE ACTUALLY SHOWING BETTER
PRECIP CHANCES FOR THE SIERRA FRIDAY AND SATURDAY, ALTHOUGH NOT A
BIG STORM BY ANY MEANS. PREVIOUS MODELS HAD SHOWN THESE WAVES AS DRY
INSIDE SLIDERS, BUT THESE LATEST RUNS SEEM TO BE EDGING THE RIDGE
FURTHER WEST TO AROUND 145W, WHICH WILL ALLOW THE SHORTWAVE DROPPING
ALONG THE WEST COAST TO BE ABLE TO PICK UP SOME MOISTURE OFF THE
PACIFIC BEFORE THEY MOVE INTO THE SIERRA.
THIS SYSTEM DOES LOOK PRETTY COLD, WITH SNOW LEVELS AT OR NEAR
VALLEY FLOORS IN WESTERN NEVADA. FORECAST CONFIDENCE ON THE COLDER
TEMPERATURES NEXT WEEKEND IS MEDIUM, BUT OVERALL CONFIDENCE IN
PRECIP AMOUNTS REMAINS LOW AS THIS RELIES HEAVILY ON THE TRACK OF
THE LOW. HOON
AVIATION...
GENERALLY VFR CONDITIONS EXPECTED FOR KTRK, KTVL, KRNO, KCXP FOR
TODAY WITH KMMH THE ONLY TERMINAL TO SEE POTENTIAL FOR ACCUMULATING
SNOWFALL. COULD SEE -SHSN FOR KMMH AS EARLY AS 15Z SUN WITH THE BEST
CHANCES FROM 21Z SUN TO 12Z MON MORNING. IT`S POSSIBLE TO SEE 1-4
INCHES AT KMMH TONIGHT THROUGH MONDAY MORNING.
BREEZY NORTHEAST SURFACE WINDS ARE EXPECTED TODAY WITH GUSTS AROUND
35 KTS. GUSTY WINDS MAY PRODUCE BLOWING DUST WITH LIMITS TO
VISIBILITY AT TIMES AROUND KRNO, KCXP, KNFL AND KLOL. AREAS OF
MOUNTAIN OBSCURATION IN THE SIERRA EXPECTED THROUGH MONDAY MORNING.
FUENTES
&&
.REV WATCHES/WARNINGS/ADVISORIES...
NV...LAKE WIND ADVISORY UNTIL 6 PM PST THIS EVENING FOR PYRAMID LAKE
IN NVZ004.
LAKE WIND ADVISORY UNTIL 6 PM PST THIS EVENING FOR LAKE TAHOE IN
NVZ002.
CA...LAKE WIND ADVISORY UNTIL 6 PM PST THIS EVENING FOR LAKE TAHOE IN
CAZ072.
&&
$$
FOR MORE INFORMATION FROM THE NATIONAL WEATHER SERVICE VISIT...
HTTP://WEATHER.GOV/RENO (ALL LOWER CASE)
AREA FORECAST DISCUSSION
NWS PUEBLO CO
327 PM MST SUN FEB 22 2015
.SHORT TERM...(THIS EVENING THROUGH MONDAY)
ISSUED AT 251 PM MST SUN FEB 22 2015
...HEAVY SNOW OVER THE MOUNTAINS CONTINUES...
...SNOW WINDING DOWN TONIGHT FOR THE LOWER ELEVATIONS...
IN GENERAL...FORECAST IS WORKING OUT FAIRLY WELL ACROSS THE CWA.
FORECAST AMOUNTS FOR THE NORTHERN AND EASTERN ZONES WERE TOO
HIGH...AND TOO LOW FOR THE MTS AND SRN ZONES...BUT OVERALL AMOUNTS
ARE NOT TOO SURPRISING. AS THE UPPER TROUGH SHEARS OFF TO THE WEST
OVER CA...AND MID LEVEL WINDS CONTINUE TO VEER TO THE SW AND
W...WILL SEE SNOWFALL GRADUALLY DIMINISH OVER THE ERN PLAINS E OF I-
25 TONIGHT...SO HAVE REDUCED POPS THROUGH TONIGHT IN THAT AREA. WILL
LEAVE A SNOW ADVISORY GOING WITH ADDITIONAL LIGHT ACCUMS OF AN INCH
OR TWO POSSIBLE...AND CONTINUED ICY ROAD CONDITIONS. HIGH RES MODELS
ARE SHOWING THE HEAVIER SNOW GRADUALLY BEING TIED TO THE ERN MTS AND
HIGHER TRRN...AND THIS LOOKS REASONABLE. THERE COULD BE SOME BANDED
PRECIP SPILLING OVER TO PORTIONS OF THE I-25 CORRIDOR...ESPECIALLY W
OF I-25...THROUGH THIS EVENING...SO WILL LEAVE THE WARNING INTACT
FOR THE I-25 ZONES. IN FACT...THE HRRR CONTINUES TO SHOW SN PICKING
UP FOR A BIT EARLY THIS EVENING OVER EL PASO COUNTY BEFORE
DIMINISHING AFTER MIDNIGHT. LATER SHIFT CAN REEVALUATE AND
DOWNGRADE THE WARNING IF IT LOOKS LIKE THIS WILL NOT MATERIALIZE.
OVER THE MTS...SNOW CONTINUES THROUGH TOMORROW. WIND SENSOR IS OUT
AT KCPW...BUT AS MENTIONED IN THE EARLIER UPDATE BLIZZARD CONDITIONS
WERE OCCURRING THERE AND WILL LIKELY CONTINUE THROUGH PERIODS OF
MONDAY BEFORE THINGS BEGIN TO QUIET DOWN. LATEST GUIDANCE SUGGESTS
AN ADDITIONAL 2-3 FEET OVER THE SAN JUANS BY TUESDAY...SO WOULD NOT
BE SURPRISED TO SEE A FEW SPOTS NEAR 4 FEET BY THE TIME THIS
ENDS...AND WITH HIGH WINDS SOME SERIOUS DRIFTING AS
WELL...INCREASING AN UNSTABLE SNOW LOAD ON THE SLOPES AND RESULTING
IN EXTREME AVALANCHE THREAT OVER THE HIGH COUNTRY FOR THE NEXT FEW
DAYS.
INTERESTINGLY...LATEST GUIDANCE IS SHOWING H7 TEMPS OF MINUS 21
DEGREES OVER OUR AREA TONIGHT...SIGNIFICANTLY COLDER THAN WHAT THE
MODELS WERE SHOWING JUST A COUPLE OF DAYS AGO...AND IN LINE WITH THE
ECMWF GUIDANCE FROM A WEEK AGO! THE MUCH COLDER AIR HAS CUT BACK A
BIT ON DENDRITIC SNOW GROWTH...AND LIMITED SNOW AMOUNTS TO SOME
EXTENT FOR OUR ERN ZONES. AS A RESULT OF THE COLDER AIR
ALOFT...EXPECT SOME LOWS CLOSE TO ZERO TONIGHT EVEN WITH THE CLOUD
COVER...AND HAVE REDUCED HIGHS A BIT FOR TOMORROW WITH TEMPS
PROBABLY STAYING IN THE TEENS FOR THE MOST PART.
EXPECT GRADUAL IMPROVEMENT TOMORROW FOR THE PLAINS...AS WRLY FLOW
INCREASES. MODELS ARE SHOWING A LACK OF QPF THERE TOMORROW...BUT
WITH ABUNDANT LOW LEVEL MOISTURE AND CONTINUED SHALLOW UPSLOPE...AM
RELUCTANT TO REMOVE POPS COMPLETELY...SO WILL LEAVE LOW POPS IN
PLACE OVER THE PLAINS. OVER THE MTS...HEAVY SNOW CONTINUES AT TIMES
WITH BLIZZARD CONDITIONS FOR THE ERN SAN JUANS. SAN LUIS VALLEY WILL
BE BETWEEN THE TWO REGIMES AND COULD SEE SOME SHSN...BUT NOTHING
PARTICULARLY HEAVY EXPECTED. WELCOME BACK TO WINTER! ROSE
.LONG TERM...(MONDAY NIGHT THROUGH SUNDAY)
ISSUED AT 251 PM MST SUN FEB 22 2015
MONDAY NIGHT THE UPR LOW IS FORECAST TO MOVE EASTWARD FROM SRN
NV...WITH THE GFS SHOWING THE LOW CENTER OVR NERN AZ BY 12Z TUE AND
THE NAM BEING A LITTLE FARTHER WEST. EITHER WAY...SNOW CONTINUES OVR
THE SWRN CO MTNS. HOWEVER WITH THE GFS BEING FARTHER EAST THAN THE
NAM...PCPN IS ALSO FORECAST TO BE OVR THE SAN LUIS VALLEY AND THE
ERN MTNS...WHILE THE NAM HAS DRY CONDITIONS EVERY BUT THE SW MTNS.
ON TUE THE UPR LOW IS EXPECTED TO CONTINUE AN EASTWARD
TRACK...MOVING ACRS NRN NM...BRINGING MAINLY SOME PCPN CHANCES TO
MAINLY THE FAR SOUTHERN PORTIONS OF THE FORECAST AREA. HIGH TEMPS ON
TUE WL BE A LITTLE WARMER...BUT STILL BELOW AVERAGE...ESPECIALLY
WITH THE SNOW COVER.
TUE NIGHT AND EARLY WED DRY CONDITIONS ARE EXPECTED OVR THE AREA AS
THE UPR LOW MOVES INTO NORTHERN TX. A NEW UPR TROF DROPS INTO THE
STATE FROM THE SOUTH BY LATE WED MORNING...PUSHING MORE COLD AIR
INTO THE AREA. IN THE LATE MORNING OR EARLY AFTERNOON HOURS...PCPN
IS EXPECTED TO SPREAD SOUTH ACRS THE AREA AS WELL...WITH PROBABLY
THE HARDEST HIT AREAS BEING THE EASTERN MTS AND IMMEDIATELY ADJACENT
PLAINS AND THE PALMER DIVIDE. THE GFS AND ECMWF ARE IN PRETTY GOOD
AGREEMENT...KEEPING PCPN ACRS MUCH OF THE SERN PLAINS AND MTNS THRU
THU NIGHT AND MUCH OF FRI AS ANOTHER UPR DISTURBANCE MOVES INTO THE
AREA FROM THE PACIFIC NW. THIS WL BRING THE POTENTIAL FOR SEVERAL
INCHES OF SNOW OVR THE MTNS. UPSLOPE FLOW OVR ERN AREAS WL HELP TO
BRING SEVERAL INCHES TO THE THE WET MTNS...SOUTHERN SANGRES AND THE
ADJACENT PLAINS...WITH MAYBE A COUPLE TO A FEW INCHES ALONG THE I-25
CORRIDOR...AND LIGHTER ACCUMULATIONS OVR THE FAR SERN PLAINS.
UNSETTLE WEATHER IS FORECAST TO CONTINUE NEXT WEEKEND AS ANOTHER
UPR TROF AFFECTS THE STATE...KEEPING THE WEATHER COOL AND BRINGING
PCPN CHANCES TO MUCH OF THE AREA AND THE POTENTIAL FOR SEVERAL
INCHES OF SNOW IN THE MTNS.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z MONDAY EVENING)
ISSUED AT 251 PM MST SUN FEB 22 2015
SN WILL GRADUALLY WIND DOWN THIS EVE FOR KPUB AND
KCOS...AS ACCUMULATING SNOW BECOMES TIED TO THE HIGHER TRRN ALONG
THE RAMPARTS...WETS...AND SANGRES. WILL STILL SEE SOME AREAS OF
LIGHT TO MDT SN MOVE OUT OVER THE I-25 CORRIDOR THIS EVE...SO THERE
WILL BE THE CONTINUED THREAT OF IFR CONDITIONS. PERSISTENT SE FLOW
SHOULD KEEP KCOS IN IFR TO LIFR CONDITIONS THROUGH MON
MORNING...WITH AREAS OF FZFG POSSIBLE IN THE MORNING DUE TO THE SNOW
PACK AND VERY COLD CONDITIONS. AT KALS...MVFR TO IFR ALSO POSSIBLE
IN PERIODS OF LIGHT SN THROUGH AT LEAST THE FIRST PART OF MONDAY.
NOT MUCH OF A BREAK BETWEEN STORMS AS ANOTHER WINTER SYSTEM LOOKS TO
IMPACT OUR AREA LATE WED INTO THU. ROSE
&&
.PUB WATCHES/WARNINGS/ADVISORIES...
WINTER WEATHER ADVISORY UNTIL 5 AM MST MONDAY FOR COZ089-093>099.
WINTER STORM WARNING UNTIL 5 AM MST MONDAY FOR COZ058>063-
072>088.
WINTER WEATHER ADVISORY UNTIL 5 PM MST MONDAY FOR COZ069>071.
WINTER STORM WARNING UNTIL 5 PM MST MONDAY FOR COZ064>067.
BLIZZARD WARNING UNTIL 11 PM MST MONDAY FOR COZ068.
&&
$$
SHORT TERM...28/ROSE
LONG TERM...28
AVIATION...ROSE
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
333 PM CST SUN FEB 22 2015
.SHORT TERM...
234 PM CST
TONIGHT THROUGH WEDNESDAY...
COLD TEMPERATURES AND DANGEROUSLY LOW WIND CHILLS TONIGHT AND EARLY
MONDAY ARE THE IMMEDIATE FORECAST CONCERNS IN THE SHORT TERM. WIND
CHILL ADVISORY REMAINS IN EFFECT FOR ENTIRE CWA FROM MIDNIGHT
TONIGHT THROUGH 10 AM CST MONDAY MORNING. COULD EVEN APPROACH
ROCKFORDS RECORD LOW OF -12 F.
1047 MB HIGH PRESSURE CENTERED OVER THE NORTHERN PLAINS THIS
AFTERNOON WILL CONTINUE TO SPREAD SOUTHEAST TO THE MID-MISSISSIPPI
VALLEY TONIGHT. ARCTIC AIR...VERY DRY AIR MASS AND CLEAR SKIES...
AND SLOWLY DIMINISHING WINDS WILL COMBINE TO PRODUCE BITTER COLD
SUB-ZERO TEMPERATURES ACROSS THE FORECAST AREA OVERNIGHT. WITH LOW
TEMPS REACHING FROM -2 TO -14 ACROSS THE CWA AND WINDS JUST UNDER 10
MPH BY MORNING...WIND CHILLS RANGING FROM NEAR 20 BELOW TO NEARLY 30
BELOW ARE EXPECTED BY SUNRISE MONDAY. THUS WIND CHILL ADVISORY
REMAINS IN EFFECT FOR ALL COUNTIES WITH NO CHANGES.
ON MONDAY...THE SURFACE HIGH AND EASTERN PORTION OF THE RIDGE AXIS
WILL CONTINUE TO PUSH SOUTHEAST ACROSS THE AREA IN THE MORNING
BEFORE BECOMING ELONGATED ACROSS THE OHIO VALLEY LATE IN THE DAY.
COLD MORNING MINS AND SHALLOW MIXING IN THE VICINITY OF THE RIDGE
WILL LIKELY KEEP DAYTIME TEMPS IN THE SINGLE DIGITS TO NEAR 10
DEGREES IN MOST AREAS...DESPITE WINDS BECOMING WEST-SOUTHWEST AND
STARTING TO INCREASE DURING THE AFTERNOON. THIS WILL LIKELY RESULT
IN A RECORD LOW-MAX TEMP FOR THE ROCKFORD AREA MONDAY...AS THE
CURRENT RECORD LOW-MAX FOR RFD 2/23 IS A FAIRLY MILD 17 DEGREES.
WIND CHILLS WILL REMAIN SUB-ZERO THROUGH THE DAY...DESPITE MOSTLY
SUNNY SKIES.
ATTENTION THEN TURNS TO ANOTHER STRONG SHORT WAVE TROUGH DIGGING
FROM MANITOBA INTO ONTARIO AND ACROSS THE NORTHERN LAKES INTO
TUESDAY...WHICH RESULTS IN DEEP SURFACE LOW PRESSURE PASSING
NORTHEAST OF THE GREAT LAKES MONDAY NIGHT AND TUESDAY AND TIGHTENING
OF THE SURFACE PRESSURE GRADIENT ACROSS THE MIDWEST. WEST-SOUTHWEST
WINDS WILL BECOME BLUSTERY MONDAY NIGHT SUPPORTING STEADY OR SLOWLY
RISING TEMPERATURES MONDAY NIGHT ESPECIALLY ACROSS THE NORTH WHERE
WINDS WILL BE STRONGEST. TEMPERATURES WILL RISE INTO THE 25-30
DEGREE RANGE DURING THE DAY TUESDAY BEFORE THE COLD FRONT TRAILING
THE CANADIAN LOW MOVES THROUGH LATE IN THE DAY...THOUGH THE GUSTY
SOUTHWEST WINDS TO 35 MPH AT TIMES WILL MAINTAIN A RAW FEEL TO THE
DAY WITH WIND CHILLS IN THE TEENS AT BEST (ABOVE ZERO AT LEAST).
CLOUDS WILL INCREASE TUESDAY MORNING AHEAD OF THE APPROACHING FRONT
WITH SCATTERED SNOW SHOWERS OR FLURRIES AT TIMES DURING THE DAY. THE
COLD FRONT MOVES THROUGH BY EARLY TUESDAY EVENING...WITH BLUSTERY
NORTHWEST WINDS BRINGING COLDER AIR BACK INTO THE REGION AT LEAST IN
A GLANCING NATURE INTO WEDNESDAY WITH SINGLE DIGIT TEMPS TUESDAY
NIGHT AND HIGHS IN THE TEENS AND WIND CHILLS IN THE POSITIVE SINGLE
DIGITS WEDNESDAY. A WEAK CLIPPER SYSTEM IS CURRENTLY PROGGED TO MOVE
JUST WEST OF THE AREA LATE WEDNESDAY AND WEDNESDAY NIGHT...WHICH MAY
BRING SOME LIGHT SNOW TO WESTERN PARTS OF THE CWA. LOW LEVEL WINDS
ALSO LOOK TO VEER MORE NORTH-NORTHEAST WHICH MAY BRING SOME LIGHT
SNOW SHOWERS INTO NORTHWEST INDIANA AND EVEN PARTS OF NORTHEAST
ILLINOIS. NOT TOO EXCITED ABOUT ACCUMULATIONS WITH LAKE EFFECT AT
THIS TIME...AS INVERSION HEIGHTS REMAIN FAIRLY LOW.
RATZER
&&
.LONG TERM...
234 PM CST
THURSDAY THROUGH SUNDAY...
REINFORCEMENT OF ARCTIC AIR CONTINUES THURSDAY AND THURSDAY NIGHT AS
ANOTHER SHORT WAVE TROUGH DIGS SOUTHEAST AND MAINTAINS DEEP LARGE
SCALE TROUGH OVER THE EASTERN CONUS. SURFACE HIGH BUILDS SOUTHEAST
FROM THE NORTHERN PLAINS THURSDAY...INTO DOWNSTATE ILLINOIS BY
FRIDAY MORNING. 850 HPA TEMPS DROP INTO THE -16 TO -20 C RANGE
DURING THE PERIOD WITH LIGHT WINDS OF THE SURFACE RIDGE AND CLEARING
SKIES AGAIN EXPECTED TO PRODUCE SUB-ZERO TEMPERATURES BY SUNRISE
FRIDAY MORNING AND HIGHS ONLY IN THE TEENS FRIDAY...WHICH FOR THE
END OF FEBRUARY IS A GOOD 20-25 DEGREES BELOW OUR NORMAL HIGHS WHICH
WOULD BE NEAR 40 FOR THE END OF THE MONTH.
LONGER RANGE MODEL SOLUTIONS DO OFFER SOME HOPE FOR A LITTLE
MODERATION IN TEMPERATURES NEXT WEEKEND...WITH A TROUGH ELONGATING
AND BECOMING CUT-OFF IN THE SOUTHWEST CONUS AND A BROAD UPPER RIDGE
DEVELOPING ACROSS THE SOUTHEASTERN CONUS SATURDAY AND SUNDAY. THUS
OUR ARCTIC HIGH EVENTUALLY MOVES OFF THE ATLANTIC COAST WITH
SOUTHERLY FLOW DEVELOPING ACROSS THE LOWER AND MIDDLE MISSISSIPPI
VALLEY BY SUNDAY. OF COURSE THIS HELPS TO FEED MILDER AND MORE HUMID
AIR NORTHWARD...FOR A NORTHERN STREAM UPPER TROUGH AND SURFACE LOW
WHICH WOULD ALSO BRING PRECIPITATION TO THE AREA SATURDAY NIGHT AND
SUNDAY. AT THIS DISTANCE HAVE MAINTAINED A CONSERVATIVE APPROACH
WITH TEMPS INTO THE MID-30S SUNDAY AND POTENTIAL FOR SOME SNOW...
THOUGH IF THESE MODEL TRENDS PERSIST IT COULD BE MILDER WITH MIXED
PRECIP OR RAIN ESPECIALLY ACROSS OUR SOUTHEAST.
RATZER
&&
.CLIMATE...
RECORD COLD TEMPERATURES ARE POSSIBLE IN ROCKFORD ON MONDAY
FEBRUARY 23RD.
RECORD LOW FOR 2/23: -12 IN 1910.
RECORD LOW MAX FOR 2/23: 17 IN 1934.
RC
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 20Z...
* NW WINDS GUSTING TO 20 KT TODAY AND HOLDING AT 320-330 DEGREES
THROUGH TONIGHT.
JEE
//DISCUSSION...UPDATED 18Z...
HIGH PRESSURE IS MOVING IN FROM THE NORTHWEST AND THE PRESSURE
GRADIENT REMAINS TIGHT OVER THE REGION THIS AFTERNOON. STILL
EXPECTING GUSTY NORTHWEST WINDS WITH MAX GUSTS ARND 20 KT THROUGH
THIS AFTERNOON. WINDS WEAKEN AS THE HIGH PUSHES EAST THIS EVENING
AND THEN BACK TO THE SOUTHWEST BY LATE TOMORROW AFTERNOON.
JEE
//ORD AND MDW CONFIDENCE...UPDATED 20Z...
* HIGH IN ALL FORECAST ELEMENTS.
JEE
//OUTLOOK FOR ORD/MDW FOR 00Z TUESDAY-12Z SUNDAY...UPDATED 12Z...
MONDAY NIGHT...VFR.
TUESDAY...STRONG SW WINDS MAINLY IN THE MORNING. MVFR CIGS POSSIBLE LATE
AFTERNOON AND EVENING WITH FLURRIES/VERY LIGHT SNOW PSBL. BREEZY
NW WINDS TUESDAY NIGHT.
WEDNESDAY AND THURSDAY...MAINLY VFR. NORTHWEST WINDS.
FRIDAY AND SATURDAY...VFR.
KMD
&&
.MARINE...
332 PM CST
HIGH PRESSURE MOVING ACROSS THE NORTHERN PLAINS AND UPPER MIDWEST
THIS AFTERNOON INTO THE EVENING IS ALLOWING FOR NORTHERLY WINDS OF
15 TO 25 KT TO CONTINUE THIS AFTERNOON...WITH THESE SPEEDS TO
LIKELY CONTINUE FOR MUCH OF TONIGHT. THIS HIGH WILL DRIFT
SOUTHEAST THROUGH THE UPPER MIDWEST AND MID MISSISSIPPI VALLEY
TONIGHT THROUGH MONDAY AND THEN REACH THE MID ATLANTIC WEST TO THE
SOUTHERN PLAINS BY EARLY TUESDAY MORNING. AS THIS OCCURS...WINDS
WILL TURN WEST AND THEN SOUTHWEST SLIGHTLY DIMINISHING ON MONDAY
MORNING...BUT THEN INCREASE ONCE AGAIN MONDAY AFTERNOON WITH TO 30
KT WINDS LIKELY LATE IN THE AFTERNOON. WINDS WILL REALLY INCREASE
MONDAY NIGHT INTO TUESDAY OUT AHEAD OF SOUTHWARD MOVING LOW
PRESSURE OVER ONTARIO...WITH GALES LIKELY. HAVE ISSUED A GALE AND
FREEZING SPRAY WARNING OVER THE ENTIRE LAKE MONDAY NIGHT THROUGH
TUESDAY NIGHT AND HAVE NOT ISSUED A GALE WARNING FOR THE NEARSHORE
AT THIS TIME. HOWEVER...THEY DO APPEAR TO BE A POSSIBILITY VERY
EARLY TUESDAY MORNING AND WILL NEED TO CONTINUE MONITORING THIS
PERIOD FOR POSSIBLE PREVAILING GALES...AND EVEN FOR A LONGER
DURATION. DO HAVE HIGH CONFIDENCE WITH THE START TIME OF THE GALES
ACROSS THE LAKE BUT HAVE LOWER CONFIDENCE WITH THE END TIME...WITH
THE GALES POSSIBLY LASTING LONGER INTO TUESDAY NIGHT.
RODRIGUEZ
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...WIND CHILL ADVISORY...ILZ003-ILZ004-ILZ005-ILZ006-ILZ008-ILZ010-
ILZ011-ILZ012-ILZ013-ILZ014-ILZ019-ILZ020-ILZ021-ILZ022-
ILZ023-ILZ032-ILZ033-ILZ039...MIDNIGHT MONDAY TO 9 AM
MONDAY.
IN...WIND CHILL ADVISORY...INZ001-INZ002-INZ010-INZ011-
INZ019...MIDNIGHT MONDAY TO 9 AM MONDAY.
LM...GALE WARNING...LMZ080-LMZ669-LMZ671-LMZ673-LMZ675-LMZ777-LMZ779-
LMZ870-LMZ872-LMZ874-LMZ876-LMZ878...9 PM MONDAY TO 3 AM
WEDNESDAY.
HEAVY FREEZING SPRAY WARNING...LMZ080-LMZ669-LMZ671-LMZ673-
LMZ675-LMZ777-LMZ779-LMZ870-LMZ872-LMZ874-LMZ876-LMZ878...9
PM MONDAY TO 3 AM WEDNESDAY.
GALE WARNING...LMZ261-LMZ362-LMZ364-LMZ366-LMZ563-LMZ565-LMZ567-
LMZ868...6 PM MONDAY TO 3 AM WEDNESDAY.
HEAVY FREEZING SPRAY WARNING...LMZ261-LMZ362-LMZ364-LMZ366-
LMZ563-LMZ565-LMZ567-LMZ868...6 PM MONDAY TO 3 AM WEDNESDAY.
SMALL CRAFT ADVISORY...INDIANA NEARSHORE WATERS UNTIL 10 PM SUNDAY.
&&
$$
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FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
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[top]
Area Forecast Discussion
NATIONAL WEATHER SERVICE LINCOLN IL
250 PM CST Sun Feb 22 2015
.SHORT TERM...(Tonight)
ISSUED AT 240 PM CST SUN FEB 22 2015
Another Arctic air mass settling into our area for tonight and
Monday bringing bitterly cold wind chills tonight through the
mid-morning hours of Monday with values in the -15 to -25 degree
range. Latest upstream observations mostly in the single digits
across north central through northeast Iowa with wind gusts up
to 30 mph at times. Early morning lows are expected to dip to
-2 in the far south to as low as -8 across the north just before
dawn Monday. The center of the Arctic high is forecast by models
to drift into southeast Iowa by 12z Monday with the surface ridge
axis extending northeast into northern Illinois. Forecast soundings
and the latest HRRR model suggests the cloud cover we have over the
area this afternoon will drift east and south later this evening
with mainly some cirrus for the first half of the night and then
a mostly clear sky is expected after midnight most areas. Current
Wind Chill Advisory will remain in place for late tonight through
9AM Monday morning.
&&
.LONG TERM...(Monday through Sunday)
ISSUED AT 240 PM CST SUN FEB 22 2015
As the center of the cold air mass drifts across the area tomorrow,
look for winds to diminish during the day but temperatures will be
slow to rise with afternoon highs struggling to 10 to 15. The high
should be moving off to our east by afternoon and early evening
with our next surface low and cold front tracking across southern
Canada southwest through the Northern Plains. Early in the evening,
surface winds will be light enough for our usual tank with early
evening temepratures before we see a steady or slowly rising trend
across the north and west, while further east with a lighter wind
flow, early morning lows will dip several degrees below zero Monday
night into Tuesday morning. As the deep surface low tracks north
of Lake Superior on Tuesday, a gusty south to southwest wind should
help the mercury climb into the mid 20s far east to the low to mid
30s far west where we should be able to mix out fairly well during the
afternoon. With the better upper forcing remaining well to our north
and very limited moisture, models not showing much if any precip
associated with the boundary as it swings across our area late in
the day, except for the GFS which continues to produce a large area
of 0.01 qpf with this system. Not worth much more than a chance for
flurries and will continue with that for later in the day on Tuesday.
Then we will see another cold air mass build gradually southeast thru
midweek.
The GFS and latest ECMWF continue to show a weak shortwave racing
southeast into the Plains on Wednesday along the periphery of the
next batch of cold air for the remainder of the work week. The
GFS keeps any precip associated with this wave to our west and
south while the latest ECMWF has trended in that direction as well
but does bring in some light QPF late Wednesday/Wednesday evening.
Based on the latest westward shift with the ECMWF, will only have
slight chances Wednesday night for light snow. Colder temperatures
filter into the area again Wednesday night with early morning lows
dropping into the single digits with wind chills dropping to near
-10 by Thursday morning.
And a real surprise here, the well below normal temperatures are
expected to hold on across our area through at least the end of
the work week with daytime highs in the teens and early morning
lows dropping into the single digits with a few below zero readings
again possible ealry Friday morning. Both the GFS and ECMWF indicate
a significant change to the upper pattern with more of a southwesterly
flow developing over the weekend which will lead to an increasing
threat for precipitation. Models showing more agreement from what
we saw yesterday with snow chances moving in starting on Saturday
night with the threat for snow or rain on Sunday with warming
temperatures. Even seeing some better agreement with the ensemble
members with respect to the pattern change along with timing of
the precip into our area later Saturday through Sunday. Temperatures
will start to turn around on Saturday and Sunday, but still average
below the nomal highs of 40 to 45 across the area for late February.
&&
.AVIATION...(For the 18Z TAFS through 18Z Monday afternoon)
ISSUED AT 1128 AM CST SUN FEB 22 2015
VFR throughout. Northerly winds continuing through the TAF pd.
Some mid clouds streaming through the region as high pressure
builds in. GFS and NAM time heights show a thinning of the
mid/high clouds moving towards morning and potentially an SKC late
morning/mid day just as the TAFs are wrapping up.
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
WIND CHILL ADVISORY from Midnight tonight to 9 AM CST Monday FOR
ILZ027>031-036>038-040>057-061>063-066>068-071>073.
&&
$$
SHORT TERM...Smith
LONG TERM...Smith
AVIATION...HJS
AREA FORECAST DISCUSSION
NWS PADUCAH KY
236 PM CST SUN FEB 22 2015
.SHORT TERM...(THIS EVENING THROUGH TUESDAY NIGHT)
ISSUED AT 235 PM CST SUN FEB 22 2015
MAIN ISSUE OF CONCERN IN THE SHORT TERM IS THE WIND CHILL ADVISORY
FOR LATE TONIGHT INTO MONDAY MORNING. THE LATEST SHORT TERM
GUIDANCE KEEPS THE STRONGEST WINDS AND COLDEST TEMPERATURES ACROSS
PORTIONS OF SOUTHEAST MISSOURI AND MOST OF SOUTHERN ILLINOIS.
AFTER COLLABORATING WITH WFOS LSX AND LMK DECIDED TO EXPAND THE
ADVISORY A ROW OF COUNTIES FARTHER SOUTH ACROSS ILLINOIS AND THEN
FROM PERRY SOUTHWARD THROUGH SCOTT AND STODDARD IN MISSOURI. IT
LOOKS A LITTLE FUNKY IN MISSOURI...BUT THAT IS DUE TO THE CORE OF
STRONGER WINDS IN THAT REGION. THE WIND CHILLS CURRENTLY FORECAST
OVER SOUTHWEST INDIANA AND ADJACENT PORTIONS OF WEST KENTUCKY DO
NOT QUITE GET DOWN TO 10 BELOW...BUT LEFT THAT ALONE BECAUSE IT
WILL BE CLOSE.
ALTHOUGH WINDS ARE EXPECTED TO BE LIGHT MONDAY NIGHT...SOUTH WINDS
WILL INCREASE QUICKLY TUESDAY MORNING AND WITH THE LOWS WELL INTO
THE SINGLE DIGITS...MUCH OF SOUTHERN ILLINOIS AND SOUTHWEST
INDIANA MAY SEE SOME NEGATIVE WIND CHILLS FOR A FEW HOURS TUESDAY
MORNING. WILL GIVE THIS A MENTION IN THE HWO.
KEPT A MENTION OF FLURRIES IN THE FORECAST LATE THIS AFTERNOON AND
EVENING ROUGHLY ALONG AND SOUTH OF A LINE FROM VAN BUREN MISSOURI
TO MURRAY KENTUCKY. THE HRRR AND WRF RUNS REALLY DRY UP ANY ECHOES
AS THEY ENTER OUR AREA...AND THERE HASN`T BEEN ANY REPORTS OF SNOW
REACHING THE GROUND THIS SIDE OF KJLN. WON`T BE COMPLETELY
SURPRISED TO SEE A FEW FLURRIES...BUT MEASURABLE SNOWFALL IS
HIGHLY UNLIKELY.
TEMPERATURES HAVE REMAINED NEARLY STEADY ACROSS THE REGION
TODAY. FIGURE THAT COLD ADVECTION WILL KICK IN AS WE HEAD INTO THE
EVENING HOURS...BUT ENDED UP RAISING LOWS A BIT FOR TONIGHT. MOS
GUIDANCE IS GIVING QUITE A RANGE FOR FIRST PERIOD LOWS.
LOOKING UPSTREAM THIS AFTERNOON...IT APPEARS THAT GUIDANCE FOR
HIGHS ON MONDAY IS A BIT TOO COLD. LEANED TOWARD THE LESS COLD
NAM/MET NUMBERS...BUT IT WILL STILL STRUGGLE TO GET THROUGH THE
TEENS IN MOST LOCATIONS. WIND CHILLS WILL REMAIN IN THE SINGLE
DIGITS ABOVE ZERO THROUGH THE AFTERNOON.
NOT SURE IF MID/HIGH CLOUDS WILL BE THICK ENOUGH TO HOLD
TEMPERATURES UP MUCH MONDAY NIGHT OR NOT. WINDS SHOULD BE LIGHT OR
CALM WITH HIGH PRESSURE OVERHEAD...SO IT WILL BE ANOTHER COLD ONE.
DEFINITELY WENT TO THE COLD SIDE OF GUIDANCE MONDAY NIGHT.
SOUTHWEST WINDS WILL INCREASE ACROSS THE AREA TUESDAY...SO A
DECENT WARM UP IS FORECAST. UNFORTUNATELY WITH TEMPERATURES
STARTING OFF SO COLD...IT WILL STRUGGLE TO GET TO THE FREEZING
MARK.
A DISTURBANCE WILL DIVE SOUTHEAST THROUGH THE GREAT LAKES TUESDAY
NIGHT. THIS WILL BRING AN INCREASE IN CLOUDS AND A WEAK COLD
FRONTAL PASSAGE THROUGH OUR REGION. LOWS TUESDAY NIGHT WILL
ACTUALLY BE MILD...RELATIVELY SPEAKING. SOME LOCATIONS WILL STAY
ABOVE 20 ALL NIGHT.
.LONG TERM...(WEDNESDAY THROUGH SUNDAY)
ISSUED AT 235 PM CST SUN FEB 22 2015
ANOTHER SURGE OF COLD HIGH PRESSURE WILL BUILD SOUTHEAST WEDNESDAY
INTO WEDNESDAY NIGHT BEHIND A WEAK COLD FRONT. THE CENTER OF THE
HIGH WILL MOVE SOUTHEAST THROUGH THE END OF THE WORK WEEK AND SETTLE
OVER THE OHIO VALLEY BY 00Z SATURDAY. TEMPERATURES WILL AGAIN DROP
OFF TO EVEN COLDER THAN SEASONAL NORMALS, WITH HIGHS THURSDAY AND
FRIDAY ONLY IN THE 20S WITH LOWS IN THE SINGLE DIGITS TO MIDDLE
TEENS.
MODELS SHOW THE HIGH DRIFTING EASTWARD FOR THE EARLY PART OF THE
WEEKEND. TEMPERATURES WILL MODERATE BACK IN THE 30S AHEAD OF OUR
NEXT WEATHER SYSTEM. ECMWF AND GFS DIFFER ON TIMING AND TRACK OF A
LOW PRESSURE SYSTEM, WITH ECMWF BEING THE FASTER OF THE MODELS WITH
MORE SUBSTANTIAL QPF. ECMWF SHOWS WIDESPREAD PRECIPITATION ACROSS
THE PAH FORECAST AREA SATURDAY NIGHT, WHILE GFS JUST SHOW MINIMAL
QPF REACHING INTO OUR SOUTHERN COUNTIES LATE SATURDAY NIGHT. BY
SUNDAY BOTH MODELS SHOW DECENT QPF ACROSS THE ENTIRE PAH FA. JUST
WENT WITH SLIGHT CHANCE POPS FOR LIGHT SNOW SATURDAY NIGHT,
INCREASING TO CHANCE POPS FOR RAIN ON SUNDAY. BOTH MODELS YESTERDAY
SHOWED THIS SYSTEM AFFECTING OUR REGION FRIDAY NIGHT INTO SATURDAY,
SO WE STILL ARE FAIRLY LOW CONFIDENCE ON TIMING. THE LATER TIMING
DOES AT LEAST ALLOW SOME "WARMER" TO GET INTO OUR AREA AHEAD OF THE
SYSTEM, THUS LEADING TO LESS WINTRY PRECIP.
&&
.AVIATION...
ISSUED AT 1145 AM CST SUN FEB 22 2015
MVFR CEILINGS CONTINUE ACROSS THE REGION AT MIDDAY. THERE IS SOME
SIGN OF CLEARING FROM THE NORTH...AND THAT SHOULD EVENTUALLY REACH
ALL SITES LATE THIS AFTERNOON/EARLY THIS EVENING. ALSO WOULD NOT
BE SURPRISED TO SEE SOME MVFR HAZE AT LEAST AT KPAH CONTINUE WELL
INTO THE AFTERNOON WITH TEMPERATURES JUST ABOVE FREEZING OVER
MELTING SNOWPACK. THE STRONGEST OF THE GUSTY NORTH WINDS SHOULD
BE OVER KCGI WHERE THEY MAY GUST OVER 20KTS THROUGH MUCH OF THE
NIGHT. THE NORTH WIND WILL SUBSIDE A BIT IN THE MORNING...WITH MID
AND HIGH CLOUDS STREAMING OVER THE AREA.
&&
.PAH WATCHES/WARNINGS/ADVISORIES...
IL...WIND CHILL ADVISORY FROM MIDNIGHT TONIGHT TO 9 AM CST MONDAY FOR
ILZ075>078-080>091.
MO...WIND CHILL ADVISORY FROM MIDNIGHT TONIGHT TO 9 AM CST MONDAY FOR
MOZ076-086-087-110-111.
IN...WIND CHILL ADVISORY FROM MIDNIGHT TONIGHT TO 9 AM CST MONDAY FOR
INZ081-082-085>088.
KY...WIND CHILL ADVISORY FROM MIDNIGHT TONIGHT TO 9 AM CST MONDAY FOR
KYZ010-014-015-018>020.
&&
$$
SHORT TERM...DRS
LONG TERM...RST
AVIATION...DRS
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
359 PM EST SUN FEB 22 2015
.SHORT TERM...(THIS EVENING THROUGH MONDAY)
ISSUED AT 305 PM EST SUN FEB 22 2015
A VERY COLD UPPER TROUGH IS SLIDING EAST ACROSS THE UPPER GREAT
LAKES REGION THIS AFTERNOON...WITH RAP ANALYZED 850MB TEMPS OF -29C
OVER WESTERN LAKE SUPERIOR. THIS HAS LED TO AFTERNOON TEMPERATURES
AROUND 25-30 DEGREES BELOW THE NORMAL HIGHS FOR THIS TIME OF YEAR
WITH 2PM TEMPERATURES RANGING FROM -10 AT KCMX TO 7 AT KMNM. THE
COLD AIR AND A FEW BREAKS IN THE ICE...OR AT LEAST AREAS OF THIN
ICE...HAS CONTINUED TO LEAD TO VERY THIN BANDS OF LAKE EFFECT OFF
LAKE SUPERIOR IN THE NORTHWEST WIND SNOW BELTS. WHILE THE BANDS HAVE
BEEN THIN...OBS AND WEBCAMS HAVE SHOWN THAT THEY CONTINUE TO BE
EFFICIENT AT REDUCING VISIBILITIES WITH ALL OF THE CLOUDY WELL BELOW
THE DGZ. THOSE VERY LOCALIZED LOWER VISIBILITIES HAVE ALSO BEEN
AIDED BY BLOWING SNOW FROM THE GUSTY NORTHWEST WINDS OF 15-30MPH.
MEANWHILE...A SURFACE HIGH IS CURRENTLY LOCATED OVER THE EASTERN
DAKOTAS AND AN ASSOCIATED SURFACE RIDGE IS NOSING INTO THE UPPER
GREAT LAKES.
THE HIGH WILL DROP SOUTHEAST INTO THE MID MISSISSIPPI VALLEY
TONIGHT...WHICH WILL PUSH A RIDGE ACROSS THE UPPER GREAT LAKES
REGION. THIS RIDGE WILL LEAD TO BACKING WINDS THROUGH THE
NIGHT...BECOMING SOUTHWESTERLY LATE TONIGHT OVER THE WEST AND MONDAY
MORNING OVER THE EAST. THESE BACKING WINDS...ALONG WITH INCREASING
SUBSIDENCE...WILL DIMINISH THE LAKE EFFECT POTENTIAL FROM THE
LIMITED HEATING FROM LAKE SUPERIOR. THUS...EXPECT SKIES TO BECOME
MOSTLY CLEAR THIS EVENING OVER MUCH OF THE AREA AS THE DIURNAL CU
DISSIPATE...WITH THE EASTERN U.P. HANGING ON THE LONGEST INTO THE
OVERNIGHT HOURS. WHILE THE CLEAR SKIES WILL PROMOTE RADIATIONAL
COOLING...THINKING THERE WILL BE ENOUGH MIXING FROM JUST ABOVE THE
SURFACE AND THE REMAINING PRESSURE GRADIENT TO KEEP LOWS FROM
GETTING AS COLD AS SEEN A FEW DAYS AGO ON THE CLEAR/CALM NIGHTS. BUT
WITH THE COLD AIR IN PLACE AND LITTLE REBOUND IN TEMPS TODAY...HAVE
LOWS IN THE TEENS AND TWENTIES BELOW ZERO FOR TONIGHT. WHEN COMBINED
WITH THE EXPECTED WINDS OF 4-8MPH TONIGHT...WIND CHILL VALUES WILL
REMAIN IN THE -25 TO -35 DEGREE RANGE THROUGH MONDAY MORNING. DO
HAVE A FEW AREAS WHERE WIND CHILLS WILL BE IN WARNING CRITERIA
(GENERALLY OVER IRON COUNTY)...BUT WITH WINDS IN THOSE AREAS ONLY
AROUND 5MPH OVERNIGHT...DIDN/T FEEL THAT THE WINDS WERE CLOSE ENOUGH
TO OUR 10MPH CRITERIA TO ISSUE THE WARNING. ALSO AM A LITTLE
CONCERNED WITH WIND CHILLS REACHING WARNING CRITERIA OVER THE
KEWEENAW PENINSULA...AS THEY HAVE BEEN BOUNCING BACK AND FORTH OVER
THE -35 CRITERIA LATE THIS MORNING AND INTO THE AFTERNOON. THIS WILL
LIKELY CONTINUE THROUGH MUCH OF THE NIGHT AS WINDS BACK AND THE
TIGHTEST GRADIENT PIVOTS OVER THAT AREA. EITHER WAY...IT WILL BE
VERY COLD ACROSS UPPER MICHIGAN TONIGHT INTO MONDAY MORNING.
OVERALL...MONDAY LOOKS TO BE QUIET ACROSS THE AREA AS THE HIGH
PRESSURE RIDGE DEPARTS. AFTER A SUNNY START TO THE DAY...MID-HIGH
CLOUDS WILL STREAM OVER THE AREA THROUGH THE AFTERNOON AHEAD OF A
COLD FRONT THAT WILL MOVE THROUGH THE AREA LATE MONDAY NIGHT. BUT
WITH ABUNDANT DRY AIR BETWEEN 900-700MB...EXPECT THE PRECIPITATION
TO STAY OFF TO THE WEST OF UPPER MICHIGAN THROUGH THE LATE
AFTERNOON. WINDS WILL GET GUSTY OUT OF THE SOUTHWEST DURING THE
AFTERNOON AND ESPECIALLY THE EVENING. THUS...ADDED PATCHY BLOWING
SNOW TO SOME AREAS OVER THE WEST DURING THE LATE AFTERNOON. WILL SEE
HIGHS REBOUND INTO THE SINGLE DIGITS AND A FEW LOWER TEENS ABOVE
ZERO TOMORROW...BUT WITH THE INCREASING WINDS IN THE AFTERNOON IT
WILL STILL FEEL VERY COLD.
.LONG TERM...(MONDAY NIGHT THROUGH SUNDAY)
ISSUED AT 356 PM EST SUN FEB 22 2015
PATTERN OF HIGH AMPLITUDE UPR RIDGE OVER THE ERN PACIFIC/WRN
NAMERICA AND DEEP TROF OVER CENTRAL AND ERN NAMERICA WL PERSIST THRU
MUCH OF THE WEEK...RESULTING IN A CONTINUED NW FLOW ALOFT THAT WL
BRING ARCTIC SURGES INTO THE UPPER LKS THRU MID WEEK. TOWARD THE END
OF THE WEEK THOUGH...FALLING HGTS OVER THE W WL ALLOW FOR A MORE
ZONAL FLOW AND SOME AIRMASS MODERATION. BUT WITH DRY HI PRES FCST TO
BE DOMINATING...LOW TEMPS MAY STILL BE QUITE COLD DESPITE THE MORE
SEASONABLE H85 AND DAYTIME TEMPS.
MON NGT/TUE...SHRTWV AND ACCOMPANYING SFC LOW DESCENDING SE INTO FAR
NW ONTARIO BY MON EVNG ARE FCST TO SLIDE JUST NE OF LK SUP DURING
THIS TIME...WITH ATTENDANT COLD FROPA MOVING OVER UPR MI LATE MON
NIGHT AND TUE MRNG. SOME LIGHT SN IN THE WAA/ISENTROPIC ASCENT
PATTERN AHEAD OF THIS DISTURBANCE WL OVERSPREAD UPR MI FM THE NW ON
MON NGT AND PERSIST INTO TUE MRNG BEFORE THE COLD FROPA. SINCE THE
MSTR INFLOW WL BE RATHER UNIMPRESSIVE...WITH MIXING RATIOS OF 1-1.5
G/KG FCST ON 280K ISENTROPIC SFC...AND VERY DRY ANTECEDENT AIRMASS
IN PLACE WHICH WL TAKE TIME TO MOISTEN...ACCOMPANYING SN ACCUMS
SHOULD BE LIMITED TO NO MORE THAN 1 TO 2 INCHES FOR MOST OF CWA WITH
MAYBE A FEW LOCATIONS SEEING 3-4 INCHES FAR EAST AND OVER TIP OF
KEWEENAW...WHERE HIGHER POPS/QPF WL BE MAINTAINED CLOSER TO THE
SHRTWV TRACK...LONGER DURATION OF ISENTROPIC ASCENT AND AREA OF
STRONGER DEEP LAYER Q-VECT CONV. ALTHOUGH MODELS SNDGS INDICATE THE
DGZ TO BE RATHER DEEP AND INTERSECTING MUCH OF THE ASSOCIATED
UVV...STRONG WINDS THROUGH THE MUCH OF THE LAYER MIGHT BREAK UP THE
DENDRITES TO A CERTAIN EXTENT. BUT AT SAME TIME...THE SMALLER FLAKES
WOULD BE MORE EFFICIENT AT RESTRICTING VSBY WHILE BEING BLOWN ABOUT
BY THE GUSTY VEERING WINDS OCCURRING UNDER THE TIGHT PRES GRADIENT
AHEAD OF THE COLD FRONT. WITH H85 THERMAL RDG OVER UPR MI ON MON NGT
AND THE GUSTY WINDS...EXPECT RELATIVELY HIGH MIN TEMPS. WSHFT TO THE
NW FOLLOWING THE TUE MORNING COLD FROPA WL DRAG ANOTHER ARCTIC
AIRMASS BACK INTO THE CWA IN THE AFTN...DROPPING H85 TEMPS TO -20C
OR COLDER AGAIN BY 00Z WED AND ALLOWING FOR AT LEAST SCATTERED LES
TO DEVELOP IN WHATEVER BREAKS THERE ARE IN LAKE SUPERIOR ICE COVER.
TUE NGT INTO WED NIGHT...MEDIUM RANGE GUIDANCE FCSTS H85 TEMPS TO
FALL AS LO AS -28C TO -30C AROUND 12Z WED IN COLD NNW FLOW AHEAD OF
THE NEXT CANADIAN HIGH PRES BUILDING TOWARD THE NRN PLAINS. THERE
MAY BE SOME LES OFF BREAKS IN THE EXTENSIVE ICE COVER...BUT THE
BIGGEST STORY WL BE WIND CHILLS AT LEAST REACHING INTO ADVY CRITERIA
TUE NIGHT INTO WED MORNING AS 950 MB WINDS ARE FCST AOA 30 KTS
DURING THE DESTABILIZING PERIOD OF CAA THAT WL DROP MIN TEMPS BLO
ZERO AGAIN. AFTER HIGHS POSSIBLY STRUGGLING TO REACH ABV ZERO OVER
THE NW CWA ON WED...ANOTHER BITTER COLD NIGHT IS IN STORE FOR WED
NIGHT WITH DOUBLE DIGIT BLO ZERO READINGS LIKELY OVER A GOOD
PORTION OF THE CWA.
THU INTO SUN...THE ARCTIC HI OVER SCENTRAL CANADA ON WED IS FCST TO
DRIFT SLOWLY TO THE ESE REACHING THE NRN PLAINS ON THU...AND THE MID
MS VALLEY AND LOWER GREAT LAKES/OH RIVER VALLEY ON FRI BEFORE
REACHING THE MID-ATLANTIC STATES ON SAT UNDER A PATTERN OF SLOWLY
RISING 5H HGTS IN THE GREAT LAKES DOWNSTREAM OF TROFFING OVER WRN
NAMERICA. THE RESULT WL BE A PERIOD OF MAINLY DRY WX UNDER DOMINANT
SFC HIGH PRES RIDGE. ALTHOUGH THERE MAY BE SOME LES MAINLY E OF
MARQUETTE INTO THU WHILE THE LLVL FLOW IS STILL NW...BACKING WINDS
TOWARD THE W AND THEN SW WL SHIFT ANY REMAINING LES OUT INTO LK SUP
BY LATE THU NIGHT. H85 TEMPS ARE FCST TO MODERATE TO -15C TO -17C BY
FRI/SAT...ALLOWING DAYTIME TEMPS TO WARM NEAR 20F UNDER A GOOD DEAL
OF SUNSHINE. HOWEVER...STILL EXPECT VERY COLD OVERNIGHT TEMPS (BLO
ZERO) AT LEAST THU NIGHT AND FRI NIGHT AS FCST PWAT IS LOWER THAN
.10 INCH UNDER LIGHT WINDS. MORE CLDS AND LIGHT MAY ARRIVE SAT NIGHT
INTO SUN IN ADVANCE OF THE NEXT APPROACHING LOW PRES TROF. &&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON)
ISSUED AT 1235 PM EST SUN FEB 22 2015
ALTHOUGH MUCH OF LAKE SUPERIOR REMAINS ICE COVERED...THERE ARE STILL
SOME LIGHT LAKE EFFECT SNOW SHOWERS IN THE NORTHWEST WIND SNOW BELTS
EARLY THIS AFTERNOON. THEY ARE LARGELY CONFINED TO AREAS NEAR
KIWD...DUE TO THE THIN ICE TO THE EAST OF THE APOSTLE ISLANDS...AND
OFF TO THE EAST OF KSAW. WITH WINDS GRADUALLY BACKING THIS AFTERNOON
INTO TONIGHT AS A HIGH PRESSURE RIDGE MOVES OVER THE AREA...EXPECT
CONDITIONS TO GRADUALLY IMPROVE TO VFR AT KIWD/KCMX. MUCH OF THE
VISIBILITY RESTRICTION AT KCMX IS DUE TO BLOWING SNOW WITH LITTLE TO
NO LAKE EFFECT CLOUDS SEEN UPSTREAM. AT KIWD...STARTING TO SEE THE
LAKE EFFECT CLOUDS PUSH TO THE EAST AND EXPECT THAT TO CONTINUE OVER
THE NEXT COUPLE OF HOURS. MEANWHILE AT KSAW...OPTED TO KEEP
CONDITIONS AT VFR FOR THE AFTERNOON WITH THE DIURNAL CU...ALTHOUGH
THE BLOWING SNOW OR CLOUDS COULD LEAD TO A BRIEF PERIOD OF HIGH END
MVFR CONDITIONS.
VFR CONDITIONS WILL PREVAIL FOR ALL SITES TONIGHT INTO MONDAY...AS
WINDS BACK TO THE SOUTHWEST AND INCREASE LATE IN THE TAF PERIOD.
GUSTY SOUTHWESTERLY WINDS ARE EXPECTED MONDAY AFTERNOON/NIGHT AHEAD
OF A COLD FRONT MOVING ACROSS THE REGION LATE MONDAY NIGHT INTO
TUESDAY MORNING. THAT FRONT WILL GIVE THE NEXT OPPORTUNITY FOR SNOW
AND REDUCED VISIBILITIES AT THE TAF SITES.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 305 PM EST SUN FEB 22 2015
HIGH PRESSURE IN THE DAKOTAS WILL MOVES INTO THE MID MISSISSIPPI
VALLEY LATE TONIGHT AND MONDAY MORNING...WHILE SHIFTING A RIDGE
ACROSS THE UPPER GREAT LAKES REGION. THIS WILL LEAD TO WEAKENING
WINDS TONIGHT...BEFORE QUICKLY INCREASING OUT OF THE SOUTHWEST ON
MONDAY AFTERNOON AHEAD OF A LOW PRESSURE SYSTEM DROPPING SOUTHEAST
THROUGH NORTHERN ONTARIO. THIS WILL LEAD TO SOUTHWESTERLY GALES OF
35-40KTS OVER PORTIONS OF LAKE SUPERIOR MONDAY AFTERNOON/EVENING
AND HAVE ISSUED A GALE WARNING FOR MUCH OF WESTERN/CENTRAL LAKE
SUPERIOR FOR LATE MONDAY AFTERNOON AND MONDAY NIGHT. THEN AS A COLD
FRONT SLIDES SOUTHEAST ACROSS LAKE SUPERIOR LATE MONDAY NIGHT INTO
TUESDAY MORNING AND SHIFT WINDS TO THE NORTHWEST. THERE MAY BE A FEW
GALE FORCE GUSTS TO 35 KNOTS BEHIND THE FRONT ON TUESDAY OVER
EASTERN LAKE SUPERIOR. A HIGH PRESSURE RIDGE WILL BUILD BACK INTO
THE AREA WEDNESDAY AND REMAIN INTO FRIDAY...LEADING TO GENERALLY
LIGHT WINDS BELOW 20KTS.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
WIND CHILL ADVISORY UNTIL NOON EST /11 AM CST/ MONDAY FOR
MIZ001>007-009>011-013-014-084-085.
WIND CHILL ADVISORY FROM 6 PM THIS EVENING TO 11 AM CST MONDAY
FOR MIZ012.
LAKE SUPERIOR...
GALE WARNING FROM 7 PM MONDAY TO 7 AM EST TUESDAY FOR LSZ266.
GALE WARNING FROM 4 PM EST /3 PM CST/ MONDAY TO 7 AM EST /6 AM
CST/ TUESDAY FOR LSZ162-263-264.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...SRF
LONG TERM...VOSS
AVIATION...SRF
MARINE...SRF
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
306 PM EST SUN FEB 22 2015
.SHORT TERM...(THIS EVENING THROUGH MONDAY)
ISSUED AT 305 PM EST SUN FEB 22 2015
A VERY COLD UPPER TROUGH IS SLIDING EAST ACROSS THE UPPER GREAT
LAKES REGION THIS AFTERNOON...WITH RAP ANALYZED 850MB TEMPS OF -29C
OVER WESTERN LAKE SUPERIOR. THIS HAS LED TO AFTERNOON TEMPERATURES
AROUND 25-30 DEGREES BELOW THE NORMAL HIGHS FOR THIS TIME OF YEAR
WITH 2PM TEMPERATURES RANGING FROM -10 AT KCMX TO 7 AT KMNM. THE
COLD AIR AND A FEW BREAKS IN THE ICE...OR AT LEAST AREAS OF THIN
ICE...HAS CONTINUED TO LEAD TO VERY THIN BANDS OF LAKE EFFECT OFF
LAKE SUPERIOR IN THE NORTHWEST WIND SNOW BELTS. WHILE THE BANDS HAVE
BEEN THIN...OBS AND WEBCAMS HAVE SHOWN THAT THEY CONTINUE TO BE
EFFICIENT AT REDUCING VISIBILITIES WITH ALL OF THE CLOUDY WELL BELOW
THE DGZ. THOSE VERY LOCALIZED LOWER VISIBILITIES HAVE ALSO BEEN
AIDED BY BLOWING SNOW FROM THE GUSTY NORTHWEST WINDS OF 15-30MPH.
MEANWHILE...A SURFACE HIGH IS CURRENTLY LOCATED OVER THE EASTERN
DAKOTAS AND AN ASSOCIATED SURFACE RIDGE IS NOSING INTO THE UPPER
GREAT LAKES.
THE HIGH WILL DROP SOUTHEAST INTO THE MID MISSISSIPPI VALLEY
TONIGHT...WHICH WILL PUSH A RIDGE ACROSS THE UPPER GREAT LAKES
REGION. THIS RIDGE WILL LEAD TO BACKING WINDS THROUGH THE
NIGHT...BECOMING SOUTHWESTERLY LATE TONIGHT OVER THE WEST AND MONDAY
MORNING OVER THE EAST. THESE BACKING WINDS...ALONG WITH INCREASING
SUBSIDENCE...WILL DIMINISH THE LAKE EFFECT POTENTIAL FROM THE
LIMITED HEATING FROM LAKE SUPERIOR. THUS...EXPECT SKIES TO BECOME
MOSTLY CLEAR THIS EVENING OVER MUCH OF THE AREA AS THE DIURNAL CU
DISSIPATE...WITH THE EASTERN U.P. HANGING ON THE LONGEST INTO THE
OVERNIGHT HOURS. WHILE THE CLEAR SKIES WILL PROMOTE RADIATIONAL
COOLING...THINKING THERE WILL BE ENOUGH MIXING FROM JUST ABOVE THE
SURFACE AND THE REMAINING PRESSURE GRADIENT TO KEEP LOWS FROM
GETTING AS COLD AS SEEN A FEW DAYS AGO ON THE CLEAR/CALM NIGHTS. BUT
WITH THE COLD AIR IN PLACE AND LITTLE REBOUND IN TEMPS TODAY...HAVE
LOWS IN THE TEENS AND TWENTIES BELOW ZERO FOR TONIGHT. WHEN COMBINED
WITH THE EXPECTED WINDS OF 4-8MPH TONIGHT...WIND CHILL VALUES WILL
REMAIN IN THE -25 TO -35 DEGREE RANGE THROUGH MONDAY MORNING. DO
HAVE A FEW AREAS WHERE WIND CHILLS WILL BE IN WARNING CRITERIA
(GENERALLY OVER IRON COUNTY)...BUT WITH WINDS IN THOSE AREAS ONLY
AROUND 5MPH OVERNIGHT...DIDN/T FEEL THAT THE WINDS WERE CLOSE ENOUGH
TO OUR 10MPH CRITERIA TO ISSUE THE WARNING. ALSO AM A LITTLE
CONCERNED WITH WIND CHILLS REACHING WARNING CRITERIA OVER THE
KEWEENAW PENINSULA...AS THEY HAVE BEEN BOUNCING BACK AND FORTH OVER
THE -35 CRITERIA LATE THIS MORNING AND INTO THE AFTERNOON. THIS WILL
LIKELY CONTINUE THROUGH MUCH OF THE NIGHT AS WINDS BACK AND THE
TIGHTEST GRADIENT PIVOTS OVER THAT AREA. EITHER WAY...IT WILL BE
VERY COLD ACROSS UPPER MICHIGAN TONIGHT INTO MONDAY MORNING.
OVERALL...MONDAY LOOKS TO BE QUIET ACROSS THE AREA AS THE HIGH
PRESSURE RIDGE DEPARTS. AFTER A SUNNY START TO THE DAY...MID-HIGH
CLOUDS WILL STREAM OVER THE AREA THROUGH THE AFTERNOON AHEAD OF A
COLD FRONT THAT WILL MOVE THROUGH THE AREA LATE MONDAY NIGHT. BUT
WITH ABUNDANT DRY AIR BETWEEN 900-700MB...EXPECT THE PRECIPITATION
TO STAY OFF TO THE WEST OF UPPER MICHIGAN THROUGH THE LATE
AFTERNOON. WINDS WILL GET GUSTY OUT OF THE SOUTHWEST DURING THE
AFTERNOON AND ESPECIALLY THE EVENING. THUS...ADDED PATCHY BLOWING
SNOW TO SOME AREAS OVER THE WEST DURING THE LATE AFTERNOON. WILL SEE
HIGHS REBOUND INTO THE SINGLE DIGITS AND A FEW LOWER TEENS ABOVE
ZERO TOMORROW...BUT WITH THE INCREASING WINDS IN THE AFTERNOON IT
WILL STILL FEEL VERY COLD.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 416 AM EST SUN FEB 22 2015
ONLY 1 MAIN SYNOPTIC SYSTEM IN THIS PERIOD...OTHERWISE COLD HIGH
PRESSURE WILL BE THE RULE. MUCH OF THE WEATHER...AND THE POTENTIAL
FOR LES ON THE W TO NW WINDS WILL BE HIGHLY DEPENDENT ON THE AMOUNT
AND THICKNESS OF THE ICE ACROSS LAKE SUPERIOR AND TO A LESSER EXTENT
LAKE MI. WILL CONTINUE TO MONITOR THE MOVEMENT OF THE ICE THROUGH
THE PERIOD.
WILL STILL NEED TO CONTEND WITH LOW WIND CHILL VALUES MONDAY
MORNING...ON THE ORDER OF 30 TO 40F BELOW ZERO...WITH THE LOWEST
READINGS IN THE TYPICALLY COLD WATERSMEET THROUGH IRON AND DICKINSON
COUNTIES. WILL CONTINUE THE ONGOING WIND CHILL ADVISORY AND
HIGHLIGHT THE VERY COLD TEMPERATURES PLAYING A BIGGER ROLE THAN THE
LIGHT TO MODERATE WINDS IN CREATING THE DANGEROUS WIND CHILL VALUES.
MONDAY WILL BE MARKED BY WAA ON INCREASING SW WINDS. 850MB TEMPS
HOVERING AROUND -23C TO START THE DAY WILL BOUNCE UP TO AROUND -11C.
AFTER THE +5 TO -6F DAY EXPECTED TODAY...HIGHS AROUND 10F MONDAY
WILL BE A BIT OF A RELIEF.
STRONG WINDS WILL RETURN. BY 00Z TUESDAY...EXPECT W 850MB FLOW OF 40-
60KTS. IN FACT IT WILL BE A PROLONGED PERIOD OF STRONG W TO NW WINDS
FROM 00Z TUESDAY-00Z WEDNESDAY...PEAKING 06-12Z TUESDAY...AS UPPER
MI RESIDES BETWEEN THE STRONG SFC HIGH EXTENDING FROM TX THROUGH THE
CENTRAL APPALACHIANS AND LOW ALONG THE N MANITOBA/ONTARIO BORDER
CROSSING CENTRAL ONTARIO AND EXTENDING A COLD FRONT OVER THE FAR W
CWA. DID NOT CHANGE FCST MUCH FROM PREVIOUS THINKING...ALTHOUGH
BLOWING SNOW WAS EXPANDED A BIT MORE.
THE COLD FRONT WILL PUSH ACROSS UPPER MI THROUGH THE DAY
TUESDAY...BRINGING WITH IT THE RETURN OF COLD AIR FROM TUESDAY NIGHT
ON. YET ANOTHER STRONG/COLD HIGH PRESSURE SYSTEM EXTENDING FROM FAR
NW CANADA THROUGH ND TUESDAY NIGHT WILL SINK INTO THE GREAT LAKES
REGION. THE SFC HIGH WILL RESIDE OVER S CENTRAL CANADA AND THE N-
CENTRAL PLAINS THURSDAY MORNING. BRIEFLY MENTIONED THAT WIND CHILL
VALUES WILL AGAIN RETURN TO 20 TO NEAR 25 BELOW ZERO.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON)
ISSUED AT 1235 PM EST SUN FEB 22 2015
ALTHOUGH MUCH OF LAKE SUPERIOR REMAINS ICE COVERED...THERE ARE STILL
SOME LIGHT LAKE EFFECT SNOW SHOWERS IN THE NORTHWEST WIND SNOW BELTS
EARLY THIS AFTERNOON. THEY ARE LARGELY CONFINED TO AREAS NEAR
KIWD...DUE TO THE THIN ICE TO THE EAST OF THE APOSTLE ISLANDS...AND
OFF TO THE EAST OF KSAW. WITH WINDS GRADUALLY BACKING THIS AFTERNOON
INTO TONIGHT AS A HIGH PRESSURE RIDGE MOVES OVER THE AREA...EXPECT
CONDITIONS TO GRADUALLY IMPROVE TO VFR AT KIWD/KCMX. MUCH OF THE
VISIBILITY RESTRICTION AT KCMX IS DUE TO BLOWING SNOW WITH LITTLE TO
NO LAKE EFFECT CLOUDS SEEN UPSTREAM. AT KIWD...STARTING TO SEE THE
LAKE EFFECT CLOUDS PUSH TO THE EAST AND EXPECT THAT TO CONTINUE OVER
THE NEXT COUPLE OF HOURS. MEANWHILE AT KSAW...OPTED TO KEEP
CONDITIONS AT VFR FOR THE AFTERNOON WITH THE DIURNAL CU...ALTHOUGH
THE BLOWING SNOW OR CLOUDS COULD LEAD TO A BRIEF PERIOD OF HIGH END
MVFR CONDITIONS.
VFR CONDITIONS WILL PREVAIL FOR ALL SITES TONIGHT INTO MONDAY...AS
WINDS BACK TO THE SOUTHWEST AND INCREASE LATE IN THE TAF PERIOD.
GUSTY SOUTHWESTERLY WINDS ARE EXPECTED MONDAY AFTERNOON/NIGHT AHEAD
OF A COLD FRONT MOVING ACROSS THE REGION LATE MONDAY NIGHT INTO
TUESDAY MORNING. THAT FRONT WILL GIVE THE NEXT OPPORTUNITY FOR SNOW
AND REDUCED VISIBILITIES AT THE TAF SITES.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 305 PM EST SUN FEB 22 2015
HIGH PRESSURE IN THE DAKOTAS WILL MOVES INTO THE MID MISSISSIPPI
VALLEY LATE TONIGHT AND MONDAY MORNING...WHILE SHIFTING A RIDGE
ACROSS THE UPPER GREAT LAKES REGION. THIS WILL LEAD TO WEAKENING
WINDS TONIGHT...BEFORE QUICKLY INCREASING OUT OF THE SOUTHWEST ON
MONDAY AFTERNOON AHEAD OF A LOW PRESSURE SYSTEM DROPPING SOUTHEAST
THROUGH NORTHERN ONTARIO. THIS WILL LEAD TO SOUTHWESTERLY GALES OF
35-40KTS OVER PORTIONS OF LAKE SUPERIOR MONDAY AFTERNOON/EVENING
AND HAVE ISSUED A GALE WARNING FOR MUCH OF WESTERN/CENTRAL LAKE
SUPERIOR FOR LATE MONDAY AFTERNOON AND MONDAY NIGHT. THEN AS A COLD
FRONT SLIDES SOUTHEAST ACROSS LAKE SUPERIOR LATE MONDAY NIGHT INTO
TUESDAY MORNING AND SHIFT WINDS TO THE NORTHWEST. THERE MAY BE A FEW
GALE FORCE GUSTS TO 35 KNOTS BEHIND THE FRONT ON TUESDAY OVER
EASTERN LAKE SUPERIOR. A HIGH PRESSURE RIDGE WILL BUILD BACK INTO
THE AREA WEDNESDAY AND REMAIN INTO FRIDAY...LEADING TO GENERALLY
LIGHT WINDS BELOW 20KTS.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
WIND CHILL ADVISORY UNTIL NOON EST /11 AM CST/ MONDAY FOR
MIZ001>007-009>011-013-014-084-085.
WIND CHILL ADVISORY FROM 6 PM THIS EVENING TO 11 AM CST MONDAY
FOR MIZ012.
LAKE SUPERIOR...
GALE WARNING FROM 7 PM MONDAY TO 7 AM EST TUESDAY FOR LSZ266.
GALE WARNING FROM 4 PM EST /3 PM CST/ MONDAY TO 7 AM EST /6 AM
CST/ TUESDAY FOR LSZ162-263-264.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...SRF
LONG TERM...KF
AVIATION...SRF
MARINE...SRF
AREA FORECAST DISCUSSION
NWS BUFFALO NY
336 PM EST SUN FEB 22 2015
.SYNOPSIS...
TEMPERATURES WILL PLUNGE TONIGHT AS ANOTHER ARCTIC FRONT SWEEPS
ACROSS THE AREA. A BRIEF BURST OF MODERATE TO HEAVY SNOW WILL
ACCOMPANY THE FRONT THIS EVENING...THEN LAKE EFFECT SNOW SHOWERS WILL
BECOME ORGANIZED ALONG THE SOUTH SHORE OF LAKE ONTARIO LATE
TONIGHT AND MONDAY. MONDAY WILL BE THE COLDEST DAY OF THE
WEEK...WITH THE POTENTIAL FOR RECORD SETTING TEMPERATURES...BUT
TEMPERATURES THE REST OF THE WEEK WILL STILL REMAIN BELOW NORMAL.
&&
.NEAR TERM /THROUGH MONDAY/...
AT 300 PM...TEMPERATURES HAVE WARMED INTO THE MID TO UPPER 20S
ACROSS MOST OF WESTERN NEW YORK WHICH FEELS RELATIVELY WARM COMPARED
TO WEATHER OVER THE PAST COUPLE WEEKS. THIS IS ABOUT TO CHANGE WITH
ANOTHER ARCTIC FRONTAL BOUNDARY ON THE DOORSTEP...ROUGHLY EXTENDING
FROM CLEVELAND TO TORONTO. RADAR SHOWS LIGHT SNOW SHOWERS UPSTREAM
ALONG THIS FRONT. BUT THESE ARE LIKELY TO INTENSIFY AS THE FRONT
PICKS UP MORE MOISTURE AND FROM INCREASED OROGRAPHICALLY ENHANCED
CONVERGENCE. HIGH RESOLUTION GUIDANCE HAS A GOOD HANDLE ON THE
POSITION OF THE FRONT...AND SHOWS INCREASING QPF...BUT BASED ON
PREVIOUS FRONTAL PASSAGES THIS WINTER SUSPECT THIS IS A BIT
UNDERDONE. THIS FRONT WILL PROBABLY PACK A DECENT PUNCH AS IT
CROSSES...BRINGING A QUICK INCH OR TWO TO THE NIAGARA FRONTIER...AND
2 TO 3 INCHES EAST OF LAKE ONTARIO WHERE UPSLOPING WILL ALSO PLAY A
ROLE. THE HRRR SEEMS TO HAVE ITS TIMING SPOT ON...SO WILL LEAN ON
THIS FOR TIMING OF THE FROPA AND SNOW SHOWERS.
THE FRONT WILL SLIDE SOUTH OF THE REGION LATE TONIGHT WITH ANOTHER
SHOT OF ARCTIC AIR POURING INTO THE REGION. TEMPERATURES WILL AGAIN
DROP BELOW ZERO...WITH THE COLDEST READINGS EAST OF LAKE ONTARIO AND
ACROSS HIGHER TERRAIN OF THE SOUTHERN TIER WHERE TEMPERATURES WILL
FALL TO 10 TO 15 BELOW. FOLLOWING THIS...HAVE UPGRADED THE WIND
CHILL WATCH TO A WARNING IN MOST AREAS. THE EXCEPTION IS IMMEDIATELY
SOUTH OF LAKE ONTARIO...WHERE CLOUDS...AND WARMING FROM THE OPEN
WATERS WILL LIMIT THE DROP IN SURFACE TEMPERATURES WHICH SHOULD KEEP
WIND CHILLS IN THE ADVISORY RANGE.
IN ADDITION TO THE COLD...LAKE EFFECT SNOWS WILL DEVELOP SOUTHEAST
OF LAKE ONTARIO. NORMALLY...850MB TEMPS DOWN TO -28C WOULD SPARK A
SIGNIFICANT LAKE RESPONSE. HOWEVER...THE ICE COVERAGES AND DRY AIR
UPSTREAM WILL PROBABLY LIMIT LAKE EFFECT INTENSITY SIMILAR TO HOW IT
DID LAST ARCTIC BLAST ONCE THE SHORTWAVE CLEARED. THE MOST
SIGNIFICANT SNOW ACCUMULATION TONIGHT WILL PROBABLY BE WITH THE
FRONT...WITH LESS ACCUMULATION FROM THE LAKE EFFECT. PARAMETERS GET
A BIT BETTER ON MONDAY WHEN WIND ALOFT BECOMES BETTER ALIGNED BUT
STILL EXPECTING ONLY LIGHT SNOW ACCUMULATIONS OF A COUPLE
INCHES. WINDS GUSTING ABOVE 25 MPH SOUTH OF THE LAKESHORE WILL
RESULT IN AREAS OF BLOWING AND DRIFTING SNOW. LAKE EFFECT SNOW WILL
START TO LIFT NORTH LATE MONDAY AFTERNOON AS WINDS SHIFT TO THE WEST.
TEMPERATURES DURING THE DAY MONDAY WILL BE BITTERLY COLD. HIGHS WILL
ONCE AGAIN STRUGGLE TO RISE ABOVE ZERO...WITH MID-DAY WIND CHILLS
STILL AVERAGING 15 TO 25 BELOW ACROSS THE REGION.
&&
.SHORT TERM /MONDAY NIGHT THROUGH WEDNESDAY NIGHT/...
THE AXIS OF HIGH PRESSURE CENTERED OVER THE UPPER OHIO VALLEY WILL
SHIFT TO THE EAST OF THE REGION AND BACK THE BOUNDARY WINDS TO
SOUTHWEST. THIS WILL PUSH ANY REMAINING LAKE EFFECT ON LAKE ONTARIO
TO THE NORTH AND NORTHEAST OF THE LAKE THROUGH TUESDAY MORNING.
TUESDAY INTO TUESDAY NIGHT ANOTHER WEAK CLIPPER LOW IS FORECAST TO
SHIFT NORTH OF THE GREAT LAKES WITH A COLD FRONT CROSSING NEW YORK
STATE. THIS SYSTEM WILL BRING A WIDE-SPREAD LIGHT SNOWFALL LATER
TUESDAY INTO TUESDAY NIGHT WITH SOME ENHANCEMENT LIKELY ACROSS THE
HIGHER TERRAIN OF THE SOUTHERN TIER AND TUG HILL. SOUTHWEST WINDS
AHEAD OF THE FRONT SHOULD HELP TEMPERATURES RISE TOWARD 20 BUT EVEN
SO IS THIS WHERE THE NORMAL LOW TEMPERATURE SHOULD BE FOR LATE
FEBRUARY. CLOUD COVER AND SNOWFALL WILL HELP KEEP TEMPERATURES
TUESDAY NIGHT TO THE MID SINGLE NUMBERS TO THE MID TEENS.
THE COLD FRONT WILL SWEEP ACROSS CENTRAL TO SOUTHEASTERN NEW YORK ON
WEDNESDAY WITH CONTINUED CHANCE OF LIGHT SNOW...THEN A COLDER ARCTIC
FRONT CROSSES THE REGION WEDNESDAY EVENING. HIGH TEMPS ON WEDNESDAY
IN THE MIDDLE TEENS WILL FALL TO THE NEGATIVE SINGLE NUMBERS
WEDNESDAY NIGHT. CHILL WESTERLIES ALONG THE LENGTH OF LAKE ONTARIO
WILL AGAIN DEVELOP THE OH-SO-FAMILIAR LAKE EFFECT SNOW ALONG THE
SOUTH TO SOUTHEASTERN SHORE COUNTIES. SYNOPTIC MOISTURE WILL BE
LACKING BUT A LAKE INDUCED EQUILIBRIUM LEVEL AROUND 8KFT MAY ALLOW
FOR A FEW INCHES OF LAKE SNOW...POSSIBLY MORE FROM MID LAKE TO THE
SOUTHEAST CORNER.
&&
.LONG TERM /THURSDAY THROUGH SUNDAY/...
YET ANOTHER ARCTIC HIGH WILL BUILD IN BEHIND THIS FRONT ON THURSDAY
WHERE NAEFS CLIMATE ENSEMBLES REGISTER THE AIRMASS AT AN EXTREME
MINIMUM. HIGHS LOOK TO ONLY RISE BACK TO THE UPPER SINGLE NUMBERS TO
LOWER TEENS. THE SPRAWLING HIGH PRESSURE WILL BE CENTERED OVER THE
UPPER PLAINS AND CANADIAN PRAIRIE PROVINCES ON THURSDAY NIGHT AND
FRIDAY. THIS WILL BRING DRYING AND SUBSIDENCE TO THE AREA WITH AN
END OF THE LAKE EFFECT AND MORE SUNSHINE. STILL COLD WITH HIGHS IN
THE TEENS.
THE UPPER PATTERN BECOMES QUASIZONAL ACROSS THE EASTERN U.S. DURING
THE END OF THE WEEK WITH A PACIFIC TROUGH MOVING ACROSS THE
INTERMOUNTAIN REGION TO THE PLAINS. HIGH PRESSURE WILL MOVE OFF THE
MIDATLANTIC COAST AND PROVIDE A SUNNIER DAY ON SATURDAY. THE RETURN
FLOW WEST OF THE HIGH CENTER WILL BRING INCREASED MOISTURE THROUGH A
DEEP LAYER SATURDAY NIGHT INTO SUNDAY. A GULF OF MEXICO LOW MOVING
INTO THE SOUTHEASTERN STATES WILL ENHANCE THIS MOISTURE FLUX AND
BRING A CHANCE OF SNOW TO THE REGION ON SUNDAY.
&&
.AVIATION /21Z SUNDAY THROUGH FRIDAY/...
AT 20Z...THERE IS A MAINLY VFR/MVFR CONDITIONS DUE TO A LINGERING
MVFR CLOUD DECK. AN ARCTIC FRONT WILL DROP ACROSS THE REGION THROUGH
03Z AND BRING A COUPLE HOURS OF MODERATE TO HEAVY SNOW...WITH SOME
GUSTY WINDS JUST BEHIND IT. STEADIEST SNOWS ARE LIKELY TO IMPACT
BUF/IAG/ART...WHERE THERE WILL BE ENHANCED CONVERGENCE AND A BIT
MORE MOISTURE. THEN LAKE EFFECT SNOW WILL DEVELOP BEHIND THE FRONT
TONIGHT...BUT THIS WILL MAINLY IMPACT ROC WITH SIGNIFICANT ICE
COVERAGE ON LAKE ONTARIO MUTING THE EFFECT SOMEWHAT. CONDITIONS WILL
IMPROVE MONDAY MORNING AS WINDS SHIFT TO THE WEST AND LIFT ANY LAKE
SNOWS NORTH OF ROC.
OUTLOOK...
MONDAY NIGHT...MAINLY VFR. A PERIOD OF LAKE EFFECT SNOW AT ART.
TUESDAY...VFR.
TUESDAY NIGHT AND WEDNESDAY...IFR. SNOW SHOWERS LIKELY.
WEDNESDAY NIGHT AND THURSDAY...SCATTERED SNOW SHOWERS WITH MVFR/IFR
POSSIBLE.
FRIDAY...VFR.
&&
.MARINE...
WINDS WILL PICK UP BEHIND AN ARCTIC BOUNDARY WHICH WILL CROSS THE
WATERS THIS EVENING. NORTHWEST WINDS WILL DIMINISHING SLIGHTLY ON
MONDAY AND THEN EVENTUALLY SHIFT TO THE SOUTHWEST AND INCREASE
MONDAY NIGHT AND TUESDAY AHEAD OF THE NEXT SHORTWAVE.
MARINE HEADLINES ARE COMPLICATED BY THE ICE FORMING ON LAKE ONTARIO.
LATEST VISIBLE SATELLITE IMAGERY SHOWS SIGNIFICANT AREAS OF ICE
ACROSS THE LAKE...WITH MANY OF THESE GETTING PUSHED BY THE FLOW.
THIS WILL HAVE AN IMPACT ON HOW LARGE WAVES BUILD...AND ALSO HOW
MUCH FREEZING SPRAY THERE IS. SINCE THERE ARE STILL SIGNIFICANT
BREAKS IN THE ICE ON WESTERN PORTIONS OF THE LAKE...WE HAVE UPGRADED
TO A HEAVY FREEZING SPRAY WARNING THERE. DESPITE THE INCREASE IN
SOUTHWESTERLY WINDS MONDAY NIGHT AND TUESDAY...WILL ONLY CARRY THE
SMALL CRAFT ADVISORY FOR THE NORTHWEST FLOW SINCE ICE COVERS MUCH OF
THE NEARSHORE WHICH WILL PROBABLY LIMIT WAVE DEVELOPMENT IN A SW
FLOW.
&&
.CLIMATE...
---AS ARCTIC AIR AGAIN SWEEPS OVER THE REGION TONIGHT RECORD LOW
TEMPERATURES ARE POSSIBLE WITHIN THE AIRMASS. THE ARRIVAL OF THE
ARCTIC AIR THIS EVENING MAY NOT ALLOW FOR TEMPERATURES TO DROP TO RECORD
LEVELS BY THE CLOSE OF MIDNIGHT. HOWEVER ON MONDAY WE MAY NEAR
RECORD LOW TEMPERATURES FOR THE DATE. BELOW ARE THE RECORD LOW
MINIMUMS...AND RECORD LOW MAXIMUMS FOR OUR CLIMATE STATIONS.
STATION: DATE RECORD LOW (F) RECORD LOW MAXIMUM (F)
BUFFALO FEB 23RD -6 (1889) 1 (1889)
ROCHESTER FEB 23RD -5 (1889) 0 (1889)
WATERTOWN FEB 23RD -29 (1972) 12 (1965)
---THIS FEBRUARY IS WRAPPING UP TO BE ONE OF THE COLDEST AND
SNOWIEST MONTHS IN OUR PRIMARY CLIMATE STATIONS HISTORY. THE
CONTINUED NORTHWEST FLOW OF BITTERLY COLD AIR HAS LEFT THE MONTH OF
FEBRUARY A HISTORIC MONTH THAT WILL BE A BENCHMARK MARK FOR YEARS TO
COME. BELOW ARE THE COLDEST MONTHS IN EACH STATIONS HISTORY.
TEMPERATURE RECORDS FOR BUFFALO AND ROCHESTER GO BACK TO
1871...WHILE TEMPERATURE RECORDS IN WATERTOWN GO BACK TO 1950.
STATION: VALUE (F) MONTH (YEAR)
BUFFALO 11.6 FEB (1934)
13.4 FEB (1875)
13.8 JAN (1977)
14.1 JAN (1918)
14.6 FEB (1885)
14.9 FEB (1979)
15.5 FEB (1978)
15.6 JAN (1920)
15.6 JAN (1912)
16.2 JAN (1945)
ROCHESTER 12.6 FEB (1934)
13.7 FEB (1979)
14.4 FEB (1875)
14.5 FEB (1885)
14.8 JAN (1918)
14.9 JAN (1994)
15.2 JAN (1945)
15.5 JAN (1977)
15.7 JAN (1981)
16.1 JAN (1920)
WATERTOWN 6.4 DEC (1989)
6.5 JAN (1970)
6.9 JAN (1994)
7.9 FEB (1978)
8.0 JAN (1981)
8.1 JAN (2004)
8.4 FEB (1979)
10.0 JAN (2003)
10.1 JAN (1977)
10.3 JAN (1961)
CURRENT MONTHLY AVERAGE TEMPERATURES ARE LISTED ON THE CF6 CLIMATE
PRODUCT.
---FEBRUARY HAS ALSO BEEN A SNOWY MONTH AS A PERSISTENT TRACK OF
CLIPPERS WITHIN A NORTHWEST FLOW HAS MAINTAINED NICKEL AND DIME
SNOWS THROUGH THE MONTH...THIS AFTER A SIGNIFICANT SYNOPTIC STORM TO
START FEBRUARY. BELOW ARE THE TOP SNOWIEST FEBRUARY`S ON RECORD.
SNOWFALL RECORDS GO BACK TO 1884.
STATION: SNOW (IN) YEAR
BUFFALO 1 54.2 1958
2 49.5 1960
3 43.7 1910
4 42.2 2015 (DATA THROUGH 2/20)
ROCHESTER 1 64.8 1958
2 58.3 1960
3 46.5 2007
4 42.7 1910
5 40.7 1978
6 40.6 2015 (DATA THROUGH 2/20)
---IT IS POSSIBLE THAT BUFFALO REMAINS BELOW FREEZING THE ENTIRE
MONTH OF FEBRUARY. THIS HAS HAPPENED ONCE BEFORE...IN THE YEAR 1978.
---ROCHESTER HAS HAD 7 DAYS THIS MONTH WITH MINIMUM TEMPERATURES
FALLING BELOW ZERO. BELOW IS A LIST OF GREATEST NUMBER OF DAYS
IN FEBRUARY WITH MINIMUM TEMPERATURES BELOW ZERO...
NUMBER YEAR
10 1979
8 1934
7 1963
7 1875
7 2015 (DATA THROUGH 2/21)
THE GREATEST NUMBER OF DAYS IN A WINTER SEASON IN ROCHESTER THAT
HAVE MINIMUM TEMPERATURES FALL BELOW ZERO IS 15 DAYS SET BACK IN
1884-85.
---WATERTOWN HAS HAD 14 DAYS THIS MONTH WITH MINIMUM TEMPERATURES
FALLING BELOW ZERO. BELOW IS A LIST OF GREATEST NUMBER OF DAYS IN
FEBRUARY WITH MINIMUM TEMPERATURES BELOW ZERO...
NUMBER YEAR
16 1978
15 1993
15 1979
14 2015 (DATA THROUGH 2/21)
&&
.BUF WATCHES/WARNINGS/ADVISORIES...
NY...WIND CHILL WARNING FROM 1 AM MONDAY TO 7 AM EST TUESDAY FOR
NYZ001-006>008-010>014-019>021-085.
WIND CHILL ADVISORY FROM 1 AM MONDAY TO 7 AM EST TUESDAY FOR
NYZ002>005.
MARINE...HEAVY FREEZING SPRAY WARNING FROM 1 AM MONDAY TO 7 AM EST
TUESDAY FOR LOZ042-043-062-063.
SMALL CRAFT ADVISORY FROM 7 PM THIS EVENING TO 1 PM EST
MONDAY FOR LOZ042-043.
&&
$$
SYNOPSIS...APFFEL
NEAR TERM...APFFEL
SHORT TERM...WCH
LONG TERM...SMITH/WCH
AVIATION...APFFEL
MARINE...APFFEL
CLIMATE...THOMAS
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
1252 PM EST SUN FEB 22 2015
.SYNOPSIS...
THE LOW PRESSURE THAT BROUGHT THE SNOW TO THE REGION WILL TRACK
WELL OFF THE EAST COAST TODAY AS YET ANOTHER ARCTIC FRONT CROSSES
THE REGION THIS EVENING. BITTERLY COLD AIR WILL FOLLOW FOR MONDAY
INTO TUESDAY WITH SUB ZERO TEMPERATURES AND AT TIMES DANGEROUSLY
COLD WIND CHILLS. SOME MODERATION IS EXPECTED TUESDAY AND
ESPECIALLY WEDNESDAY AS HIGHS REACH INTO THE 20S AND LOWER 30S.
&&
.NEAR TERM /THROUGH MONDAY/...
11 AM UPDATE... JUST MINOR TWEAKS MADE TO SKY AND TEMP GRIDS
ATTM...BASED ON THE LATEST OBSERVATIONAL DATA.
RECENT SAT IMAGERY HAS SHOWN SOME BREAKS IN THE LOW CLDNS OVER
PTNS OF WRN/CNTRL NY AND NRN PA. ALTHOUGH WE EXPECT TO SEE SOME
THINNING OF THE CLDS THIS AFTN...WE THINK CLDS WILL STILL HAVE THE
UPPER HAND OVERALL...GIVEN THE STEEP THERMAL INVERSION NOTED ON THE 12Z
KBUF SNDG...AND THE LIKELIHOOD THAT BLYR MOISTURE WILL BE TRAPPED
BLO THIS FEATURE.
DESPITE THE CLDS...TEMPS WILL BE FAIRLY MILD COMPARED TO OUR
RECENT BITTER COLD STRETCH...WITH HIGHS IN THE UPR 20S-LWR 30S IN
MOST AREAS.
IT STILL APPEARS THAT MOST OF THE FLRYS/-SHSN EXPECTED ALG AND AHD
OF TNT`S ARCTIC FROPA WILL HOLD OFF TIL VERY LATE IN THE DAY...OR
MORE LIKELY THIS EVE.
PREV DISC... THE LAST OF THE LIGHT SNOW AND FLURRIES WAS EXITING
NE PA AND SULLIVAN COUNTY AT THIS TIME AS AN UPPER LEVEL WAVE
RIPPLES INTO NY AND PA ERLY THIS MORNING. THERE HAS BEEN NO
REPORTS OF FREEZING DRIZZLE ANYWHERE IN CNTRL OR WRN NY OR NRN AND
WRN PA AND LOOKING AT THE SOUNDINGS I REALLY DON/T SEE ANY
POTENTIAL. SFC WET BULB TEMPERATURES WERE RUNNING ARND -7C AND
WITH UPLIFT IT WUD BE COLD ENUF FOR SOME ICE CRYSTAL GROWTH. MODELS
ARE SHOWING SUBSDC BEHIND THIS UPPER WAVE ANYWAY SO NOT EXPECTING
ANY WIDESPREAD FREEZING DRIZZLE. THUS HAVE DROPPED WINTER WEATHER
ADVISORY.
THE REST OF THE MORNING INTO THE AFTERNOON LOOKS TO BE CLOUDY AS
CAA BEGINS AND TRAPS MOISTURE UNDER A SHARP INVERSION ARND 900
MB. ANOTHER ARCTIC FRONT IS POISE TO PASS THRU THE REGION THIS
EVENING SO MUCH OF THE AFTERNOON WILL BE ALMOST SEASONABLE IN
TEMPERATURES. ARCTIC FRONT PASSES BY THIS EVENING. SOUNDINGS
SUGGEST THAT THE INVERSION RISES TO ABT 850 MB WHEN THE ARCTIC
PASSES BY WITH MINIMAL CAPE. THERE CUD BE SOME SNOW SQUALLS BUT
AT THIS TIME IT DOESN`T LOOK LIKE A MAJOR SNOW SQUALL EVENT.
HOWEVER...IT WILL DEPEND ON HOW WARM IT GETS THIS AFTERNOON.
CONVECTION ALLOWING MODELS THIS FAR OUT(WRF_NMM AND WRF_ARW) ARE
NOT SHOWING ANYTHING SIGNIFICANT EITHER. IT WILL BE INTERESTING TO
SEE IF THE RAP AND HRRR CATCH ONTO SOMETHING WHEN THEY GET TO THIS
EVENINGS TIME PERIOD. THIS IS SOMETHING TO PASS ONTO THE NEXT
SHIFT.
AFTER ARCTIC FRONT PASSES BY...THE USUAL 290 DEGREE LES SETS UP
BUT IT LIKELY WILL BE TOO DRY FOR ANY MAJOR ACCUMULATIONS
DOWNWIND...MAYBE SEVERAL INCHES AT BEST. BIG STORY WILL BE ANOTHER
SHOT OF ARCTIC AIR ON FAIRLY STRG NW WINDS. MINS MONDAY AM WILL BE
FROM ZERO TO 15 BELOW IN NY STATE WITH WIND CHILLS BETWEEN 20 AND
30 BELOW ZERO AS IT STANDS NOW. SO HAVE HOISTED A WIND CHILL WATCH
FOR TONIGHT AND MONDAY MORNING TO GIVE EVERYONE A HEAD`S UP ON
ANOTHER COLD MONDAY MORNING. THE WC WATCH IS FOR NY COUNTIES
EXCEPT SULLIVAN CO AND FOR NRN PA COUNTIES IN ERN PA.
MONDAY WILL BE ANOTHER COLD AND WINDY DAY WITH TEMPERATURES
STRUGGLING TO GET OUT ABOVE ZERO IN NRN NY AND BARELY REACHING 10
DEGREES IN NE PA.
&&
.SHORT TERM /MONDAY NIGHT THROUGH WEDNESDAY/...
FOR MONDAY NIGHT...YET ANOTHER BRUTALLY COLD NIGHT IS IN STORE AS
THIS HISTORICALLY COLD FEBRUARY CONTINUES. MINS LIKELY WILL DROP
TO 5 BELOW TO 20 BELOW OR LOWER. THEN TUESDAY THERE IS A SOUTHERLY
FLOW IN ADVANCE OF ANOTHER SYSTEM TRACKING INTO QUEBEC. THIS WILL
LEAD TO SOME MODERATION AND A CHANCE OF SNOW SHOWERS BY TUESDAY
NIGHT.
&&
.LONG TERM /WEDNESDAY NIGHT THROUGH SATURDAY/...
LTL CHG IN THE PTRN WITH THE BROAD...STABLE...AND STRONG ERN US
TROF REMAINS IN PLACE. NW FLOW MAY RESULT IN SOME MSTLY LGT LE AT
TIMES OVER THE NRN CWA...OTRW CONDS SHD BE MAINLY COLD AND DRY.
SOME SLGT RELAXATION IN THE PTRN AS THE CNTR OF THE TROF DRFTS
WEST TO THE GREAT LAKES...AND SW FLOW BRINGS SOMEWHAT MILDER AIR
INTO THE REGION. STILL...LOOKS AS THOUGH WE WILL REMAIN BLO NRML
ON TEMPS THRU THE END OF THE PD. WEAK WV LATE FRI EARLY SAT MAY
BRING SOME LGT SNOW NEAR THE END OF THE LONG TERM.
GNRLY FLWD HPC GUID FOR THE FCST...ALTHOUGH HAVE ONCE AGAIN BUMPED
UP POPS A BIT IN THE PTNL LE AREAS.
&&
.AVIATION /18Z SUNDAY THROUGH FRIDAY/...
LL MOISTURE TRAPPED BENEATH THE STABLE LYR RESULTING IN MSTLY MVFR
CIGS THIS AFTN. FEW BREAKS IN THE CLDS AND IF HTG CAN GET
GOING...SCT TO VFR CONDS PSBL. TNGT...ANOTHER ARCTIC FNT PASSES
THRU THE AREA WITH A 2 OR 3 HR PD OF MVFR SNOW SHWRS. BRIEFLY LWR
VSBYS AND CIGS PSBL. BHD THE FNT...A RETURN VFR CONDS FOR A
TIME...BUT LAKE CLDS AND GNRLY LGT SNOW SHWRS WILL DVLP IN THE
CAA...ESP AT SYR AND RME. GUSTY WINDS RETURN IN STRONG CAA MON...SO
BLSN MAY BE AN ISSUE AT SOME STATIONS.
.OUTLOOK...
MON...MVFR/IFR RESTRICTIONS PSBL IN SNOW SHWRS.
MON NGT-TUE...VFR.
TUE NGT-WED...RESTRICTIONS PSBL AGN IN SNOW SHWRS/LGT SNOW...ESP CNY.
WED NGT-THU-FRI...MAINLY VFR.
&&
.BGM WATCHES/WARNINGS/ADVISORIES...
PA...WIND CHILL WATCH FROM MIDNIGHT EST TONIGHT THROUGH MONDAY
MORNING FOR PAZ038-039.
NY...WIND CHILL WATCH FROM MIDNIGHT EST TONIGHT THROUGH MONDAY
MORNING FOR NYZ009-015>018-022>025-036-037-044>046-
055>057.
&&
$$
SYNOPSIS...DJN
NEAR TERM...DJN/MLJ
SHORT TERM...DJN
LONG TERM...DGM
AVIATION...DGM
AREA FORECAST DISCUSSION
NWS RALEIGH NC
100 PM EST SUN FEB 22 2015
.SYNOPSIS...A COLD FRONT WILL MOVE EAST...CROSSING CENTRAL NC LATE
THIS AFTERNOON AND EVENING. LOW PRESSURE WILL DEVELOP AND MOVE ALONG
THE FRONT TO OUR SOUTH TONIGHT. CHILLY HIGH PRESSURE WILL NOSE INTO
OUR AREA FROM THE NORTHWEST MONDAY AND MONDAY NIGHT.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 1035 AM SUNDAY...
THE PRE-FRONTAL RAIN BAND IS DISSIPATING AND EXITING THE COASTAL
PLAN ON THE HEELS OF THE LOW-LEVEL JET MOVING UP THE MID-ATLANTIC
COAST. RADAR TRENDS WARRANT CATEGORICAL POPS OVER THE SOUTHERN
COASTAL PLAIN FOR A COUPLE MORE HOURS...AND THEREAFTER THE HRRR
SUGGESTS ONLY A SLIGHT CHANCE DURING THE EARLY AFTERNOON. THERE IS
AN AREA OF SPOTTY PRECIP ASSOCIATED WITH A WEAK WAVE OF LOW PRESSURE
ALONG THE SYNOPTIC FRONTAL ZONE APPROACHING THE ATLANTA METRO
AREA...AND THE HRRR SHOWS THAT PRECIP MOVING INTO THE SOUTHERN CWA
BY 00Z. THE ASSOCIATED WARM ADVECTION IS WEAK...SO ITS UNCLEAR HOW
LARGE OF AN AREA WILL BE AFFECTED. WILL SHOW A CHANCE POP IN
THE SOUTHEAST AFTER 22Z.
THE TEMPERATURE FORECAST TODAY IS STILL UNCERTAIN WITH GUIDANCE ALL
OVER THE PLACE. THE COLD FRONT IS STILL WEST OF THE
MOUNTAINS...WHILE THE WEDGE FRONT IS HUNG UP BETWEEN THE US-1 AND I-
95 CORRIDORS. WEAK ADVECTION AHEAD OF THE COLD FRONT WILL LEAVE
TEMPS TO BE MAINLY INFLUENCED BY HEATING. VISIBLE IMAGERY SHOWS
SOME BREAKS IN THE CLOUDS WITH THE WESTERLY FLOW ALOFT...BUT IT MAY
TAKE A LITTLE WHILE TO ERODE THE STRATUS THAT APPEARS TO BE AT LEAST
2000FT THICK PER PIREPS AND RAP SOUNDINGS. EXPECT HIGHS TO
ULTIMATELY RANGE FROM THE UPPER 40S IN THE FAR NORTHWEST TO THE
UPPER 50S IN THE SOUTHEAST...THOUGH ADMITTEDLY CONFIDENCE IS BELOW
AVERAGE. -BLS
TONIGHT: ANA-FRONTAL PRECIP WILL QUICKLY SPREAD/FILL NORTH INTO THE
AREA BETWEEN 04 TO 12Z IN RESPONSE TO MOIST LOW-LEVEL UPGLIDE ALONG
...WITH FORCING FURTHER AIDED ON THE COOL SIDE OF THE FRONT VIA
TIGHTENING HORIZONTAL THERMAL GRADIENT/STRENGTHENING LOW-LEVEL
FRONTOGENETICAL RESPONSE AS STRONG +1040 ARCTIC HIGH OVER THE MID
BEGINS TO BUILD INTO THE REGION. GUIDANCE HAS REALLY TRENDED WETTER
FOR TONIGHT WITH QPF AMOUNTS...ESPECIALLY THE EC AND NAM INDICATING
AS MUCH AS A HALF TO TWO-THIRDS OF AN INCH ACROSS THE SANDHILLS AND
SOUTHERN COASTAL PLAIN...WITH A SHARP CUT-OFF IN PRECIP SE-NW.
TEMPERATURES WILL BE CLOSE TO FREEZING ACROSS THE FAR
NORTH/NORTHWEST(ROXBORO/WINSTON SALEM). CANNOT RULE OUT A BRIEF
MIXTURE OF WINTRY PRECIP...BUT AT THIS TIME QPF AMOUNTS LOOK
LIMITED WITH NO ACCUMULATION EXPECTED AS THIS SYNOPTIC SET-UP
WITH COLD AIR TRYING TO CATCH UP WITH THE PRECIP/MOISTURE RARELY SUPPORTS
MUCH MORE THAN ADVISORY CRITERIA. WILL CONTINUE TO MONITOR.
LOWS RANGING FROM LOWER 30S NORTH TO LOWER 40S SOUTHEAST.
&&
.SHORT TERM /MONDAY THROUGH TUESDAY NIGHT/...
AS OF 320 AM SUNDAY...
MAIN FRONTAL ZONE IS OFFSHORE AND STRETCHING BACK TO THE WEST
SOUTHWEST ACROSS SOUTH CAROLINA MONDAY MORNING. ARCTIC AIR WITH
DEEPER SUB-ZERO TEMPERATURE PROFILES WILL BE EDGING SOUTH IN COLD
AIR ADVECTION SPILLING IN BEHIND THE FRONT. MEANWHILE...
CYCLOGENESIS ALONG THE FRONT OVER SOUTH CAROLINA ASSOCIATED WITH A
SOUTHERN STREAM SHORTWAVE WILL DELAY THE EXIT OF ANAFRONTAL PRECIP
ACROSS THE SOUTHERN HALF OF THE AREA UNTIL LATE MORNING/EARLY
AFTERNOON. WILL HAVE CHANCE TO LIKELY POPS OVER THE EAST AND SOUTH
THROUGH 18Z-ISH...INDICATING A CHANGEOVER FROM RAIN TO A MIX OR ALL
SNOW PROGRESSING SOUTHWARD AS THE MORNING PROGRESSES. THE DRY COLD
AIR WILL BE CHASING THE PRECIP SOUTH RESULTING IN VERY LIGHT AMOUNTS
IN CHANGEOVER ZONE...SO NO ISSUES ARE ANTICIPATED. PRECIP SHOULD
REMAIN ALL RAIN ACROSS THE SOUTH AS IT EXITS IN THE EARLY AFTERNOON.
HIGHS WILL SHOW LITTLE INCLINATION TO CLIMB BEYOND THE UPPER 30S
ACROSS THE NORTH...AND TOP OUT IN THE VERY LOW 40S SOUTH.
SKIES WILL BE CLEARING AS OUR NEXT ARCTIC HIGH MOVES ACROSS THE
SOUTHERN OHIO VALLEY AND MAKES THE USUAL RIGHT TURN DOWN THE
ATLANTIC SEABOARD. RADIATIONAL CONDITIONS WILL BE IMPROVING BY
MORNING AS THE HIGH SETTLES IN WITH CLEAR SKIES AND TEMPS MONDAY
NIGHT WILL BOTTOM OUT FROM 15 TO 20 ACROSS THE NORTH...AND IN THE
LOWER 20S SOUTH. TUESDAY WILL BE DRY...AS WE ARE IN THE ZONE BETWEEN
THE STALLED FRONTAL ZONE TO OUR SOUTH AND BROAD UPPER TROFFING
ACROSS THE EASTERN CONUS WITH MID TO HIGH CLOUDINESS STREAMING
ACROSS THE AREA. ANOTHER 15 DEGREE BELOW NORMAL DAY IS ON TAP
TUESDAY WITH HIGHS WITHIN A DEGREE OR SO EITHER SIDE OF 40. THE
SURFACE HIGH MOVES OFFSHORE AND LIGHT SOUTHERLY FLOW WILL PROVIDE A
LITTLE BUMP INTO THE MID 20S FOR MINS TUESDAY NIGHT.
&&
.LONG TERM /WEDNESDAY THROUGH SATURDAY/...
AS OF 315 AM SUNDAY...
WE CATCH A LITTLE WARMUP ON WEDNESDAY AHEAD OF A DRY REINFORCING
ARCTIC FRONT MOVING THROUGH LATE IN THE DAY. HIGHS WILL BE IN THE
UPPER 40S TO LOWER 50S. CONFIDENCE FALLS OFF AS WE DIG FURTHER INTO
THE EXTENDED PERIOD DUE TO THE MYRIAD OF FEATURES TO CONSIDER FROM
BOTH THE NORTHERN AND SOUTHERN STREAM. A SOUTHERN STREAM SHORT WAVE
NOTED YESTERDAY WILL INDUCE ANOTHER WAVE ON THE STALLED SURFACE
FRONT SOUTH OF THE AREA WEDNESDAY NIGHT...POTENTIALLY WRAPPING SOME
RAIN INTO THE SOUTHEAST LATE WEDNESDAY NIGHT INTO THURSDAY
MORNING...BUT AT THIS POINT THE WAVE LOOKS TO REMAIN WELL SOUTH AND
POPS WILL BE IN THE SLIGHT CHANCE CATEGORY. MINS WEDNESDAY NIGHT
WILL BE MOSTLY IN THE MID 20S...WITH COLD AIR BEHIND THE ARCTIC
FRONT SETTLING IN ON THURSDAY AND LIMITING HIGHS TO THE UPPER 30S TO
LOWER 40S EACH DAY THROUGH SATURDAY. DETAILS FOR LATE WEEK REMAIN
HIGHLY SUSPECT...BUT AT THIS POINT IT WOULD APPEAR THAT OUR BEST
CHANCE FOR PRECIP WOULD BE LATER FRIDAY INTO SATURDAY AS A STRONG
SHORT WAVE IN THE NORTHERN FLOW LIFTS OUT OF THE FILLING EASTERN
TROF AND HAS POTENTIAL TO INTERACT WITH THE SOUTHERLY SUPPRESSED
FRONTAL ZONE.
&&
.AVIATION /18Z SUNDAY THROUGH FRIDAY/...
AS OF 100 PM SUNDAY...
LOW CLOUDS ARE SLOWLY ERODING THIS AFTERNOON...WITH VFR NOW IN THE
TRIAD AT KRWI/KFAY. THE LAST REMAINING AREA OF MVFR CEILINGS SHOULD
SCOUR IN THE NEXT COUPLES OF HOURS AND A PERIOD OF VFR IS EXPECTED
AT KRDU AFTER 20Z. A COLD CURRENTLY CROSSING THE APPALACHIANS WILL
SINK SOUTH THROUGH THE AREA THIS EVENING WITH WINDS SHIFTING TO
NORTH-NORTHEASTERLY IN THE 21Z TO 03Z TIME FRAME. MEANWHILE...A
WAVE OF LOW PRESSURE CURRENTLY OVER THE GULF COAST STATES WILL
STRENGTHENING AND MOVE ALONG THE COLD FRONT...BRING LOW CLOUDS
AND RAIN BACK ACROSS AT LEAST THE SOUTHERN HALF OF NC. THERE IS
GOOD CONFIDENCE THAT CEILINGS WILL LOWER TO MVFR AFTER 00Z AND TO
IFR AFTER 06Z AS THE RAIN SPREADS IN. THESE CONDITIONS WILL BE
PRETTY MUCH UNCHANGED THROUGH THE MORNING HOURS UNTIL THE RAIN ENDS
BY MID AFTERNOON.
OUTLOOK...A PERIOD OF VFR CONDITIONS IS EXPECTED BY TUESDAY.
ANOTHER WAVE OF LOW PRESSURE WILL CROSS THE SOUTHEAST US LATE
WEDNESDAY AND MAY BRING ADDITIONAL ADVERSE AVIATION CONDITIONS
MAINLY TO TERMINALS ACROSS SOUTHERN NC
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...CBL
NEAR TERM...CBL/BLS
SHORT TERM...MLM
LONG TERM...MLM
AVIATION...BLS
AREA FORECAST DISCUSSION
NWS NORMAN OK
1138 AM CST SUN FEB 22 2015
.AVIATION...
SNOW SHOWERS WILL CONTINUE TO MOVE OUT OF NORTHERN OKLAHOMA THIS
AFTERNOON. ANOTHER ROUND OF MIXED PRECIP WILL IMPACT SOUTHERN AND
CENTRAL SITES THIS AFTERNOON AND EVENING. FINALLY...A THIRD ROUND
OF SNOW WILL IMPACT WESTERN SITES TOMORROW MORNING. ANY OF THESE
SHOWERS COULD BRING VISIBILITIES DOWN TO IFR OR EVEN LIFR
CONDITIONS AT TIMES. WINDS WILL REMAIN NORTHERLY AND GUSTY
THROUGHOUT THE TAF PERIOD.
&&
.PREV DISCUSSION... /ISSUED 1040 AM CST SUN FEB 22 2015/
UPDATE...
SNOW CONTINUES ACROSS PARTS OF NORTHERN OK THIS MORNING. THIS
SHOULD CONTINUE INTO EARLY AFTN BEFORE DIMINISHING SO WILL EXTEND
THE WINTER WEATHER ADVISORY TO 21Z. WITH ONLY LIGHT SNOW OCCURRINGIN
NW PARTS OF AREA WILL ALSO CHANGE THE WINTER STORM WARNING TO AN
ADVISORY.
AREA OF RAIN/SLEET/SNOW WILL CONTINUE TO MOVE ACROSS PARTS OF
SOUTHERN OKLAHOMA AND WESTERN NORTH TEXAS THIS AFTERNOON. ISOLATED
THUNDER HAS BEEN SEEN IN THIS AREA BUT THE OCCURRENCE OF THUNDER
IN THE FA HAS DIMINISHED OVER THE PAST HOUR OR SO. THERE STILL MAY
BE A FEW CLAPS OF THUNDER THIS AFTERNOON.
COLD AIR WILL CONTINUE TO MOVE ACROSS THE REGION TODAY CONTINUING
TO CAUSE FALLING TEMPERATURES THIS AFTERNOON. WINDY CONDITIONS
WILL ALSO CONT THIS AFTN WITH OCCASIONAL GUSTS OVER 40 MPH IN
WESTERN PARTS OF THE AREA ALONG AND SOUTH OF I-40. THE WINDY
CONDITIONS COMBINED WITH THE COLD TEMPERATURES WILL ALSO CONTINUE
TO CAUSE COLD WIND CHILLS ACROSS THE AREA WITH MUCH OF THE AREA
DROPPING TO THE TEENS AND SINGLE DIGITS. A FEW LOCATIONS COULD
ALSO HAVE WIND CHILLS AROUND ZERO DEGREES. UPDATES OUT SOON.
PREV DISCUSSION... /ISSUED 549 AM CST SUN FEB 22 2015/
AVIATION...
A STRONG COLD FRONT IS MOVING THROUGH THE AREA WITH GUSTY NORTH
WINDS AND IFR-MVFR CIGS ACROSS NORTHERN OKLAHOMA... WHICH WILL
SPREAD INTO SOUTHERN OKLAHOMA AND NORTH TEXAS AS THE FRONT MOVES
THROUGH. MVFR CIGS AND GUSTY WINDS WILL SPREAD INTO SOUTHERN
OKLAHOMA AND NORTH TEXAS AS THE FRONT PROGRESSES. AREAS OF SNOW
ARE OCCURRING IN NORTHERN AND WESTERN OKLAHOMA WITH MORE
RAIN/SNOW/SLEET EXPECTED TO SPREAD INTO NORTH TEXAS AND SOUTHERN
OKLAHOMA FROM SOUTHWESTERN TEXAS THROUGH THE DAY. WIDESPREAD MVFR
OR LOWER CIGS WILL PERSIST THROUGH THE FORECAST PERIOD.
PREV DISCUSSION... /ISSUED 442 AM CST SUN FEB 22 2015/
DISCUSSION...
WINTER WEATHER ROUND NUMBER 1 IS UNDERWAY CURRENTLY IN NORTHWEST
OKLAHOMA... BUT NOT WITHOUT COMPLICATIONS. FIRST IS THE RELATIVELY
SLOW ARRIVAL OF THE COLD AIR BRINGING A LATER TRANSITION TO
SNOW... AND SECOND IS THE SPLIT MESOSCALE BANDING THAT HAS
DEVELOPED WITH ONE BAND IN SOUTHWEST KANSAS NEAR DODGE CITY AND
SECOND FROM DUMAS TEXAS TO WATONGA TO GUTHRIE. WITH THE SOUTHERN
BAND PERSISTING AND MOVING EAST... THIS WARRANTS EXPANDING THE
WINTER WEATHER ADVISORY INTO NORTH CENTRAL OKLAHOMA WHERE TRENDS
AND HRRR SUGGEST AN INCH OF SNOW OR SO MAY FALL. ALTHOUGH THE
SPLIT MESOSCALE BANDS HAVE FORMED ON EITHER SIDE OF THE WARNING IN
NORTHWEST OKLAHOMA... WILL NOT DOWNGRADE NOW AS SOME DECENT
SNOWFALL IS STILL POSSIBLE DEPENDING ON HOW THE BANDS EVOLVE
ALTHOUGH RIGHT NOW IT LOOKS LIKE THE HEAVIEST SNOW THIS MORNING
MAY BE NEAR THE ARNETT-TALOGA-WATONGA LINE.
ROUND NUMBER 2 WILL BEGIN TO DEVELOP ACROSS TEXAS AND SPREAD INTO
THE AREA LATER THIS MORNING. COOLING CLOUD TOPS ARE BEING OBSERVED
IN SOUTHWEST TEXAS RIGHT NOW AND RADARS ARE BEGINNING TO DETECT
SOME DEVELOPING ECHOES ACROSS WEST TEXAS. PRECIPITATION WILL
BECOME MORE WIDESPREAD AND THEN SPREAD INTO SOUTHERN PART OF OUR
FORECAST AREA TODAY. AS THE COLD AIR CONTINUES TO SPREAD SOUTH...
PRECIPITATION WILL MIX WITH AND THEN CHANGE TO SNOW THIS AFTERNOON
IN THE SOUTH. AS WAVE NUMBER 2 EXITS TONIGHT... WAVE NUMBER 3
MOVES IN FROM THE WEST AND SPREADS ACROSS THE AREA LATE TONIGHT
AND MONDAY. MODELS SUGGEST MESOSCALE BANDING WILL BE POSSIBLE
AGAIN MAINLY HIGHLIGHTING SOUTHERN OKLAHOMA... BUT AS USUAL THERE
IS SOME UNCERTAINTY ON THE SPECIFIC PLACEMENT OF ANY SMALL SCALE
FEATURES THAT DEVELOP.
RAIN/SNOW WILL BE THE PRIMARY PRECIPITATION TYPES THROUGH THESE
PRECIPITATION EVENTS... BUT SLEET WILL ALSO BE POSSIBLE. IN THE
SOUTH TODAY... THERE MAY BE ENOUGH OF A WARM LAYER TO PARTIALLY
MELT THE SNOW AS IT FALLS BEFORE REFREEZING IN THE COLD LAYER
BELOW. BUT THERE ARE ALSO SUGGESTIONS THAT WE MAY LOSE MOISTURE IN
THE DENDRITIC GROWTH ZONE REGIONS ALOFT AT TIMES THROUGH THIS
EVENT SUGGESTING SUPERCOOLED WATER FREEZING IN THE COLD LAYER.
ALTHOUGH FREEZING RAIN IS NOT COMPLETELY OUT OF THE QUESTION IN
THE SOUTH TODAY... DEPTH OF FORECAST LOW-LEVEL COLD LAYER
INDICATES THAT SLEET IS MORE LIKELY.
THERE WILL BE A BREAK IN THE PRECIPITATION CHANCES TUESDAY AND
WEDNESDAY WITH WARMER TEMPERATURES WEDNESDAY. THEN MORE COLD AIR
ARRIVES AND PRECIPITATION CHANCES REDEVELOP WEDNESDAY
NIGHT/THURSDAY. ALTHOUGH THERE IS AGREEMENT IN THE GENERAL PATTERN
SHIFT... THERE REMAIN DIFFERENCE IN THE MEDIUM RANGE MODELS ON THE
FINER DETAILS WHICH ARE SUFFICIENT ENOUGH TO GIVE LOW CONFIDENCE
IN THE LATER PERIODS OF THE FORECAST.
&&
.PRELIMINARY POINT TEMPS/POPS...
OKLAHOMA CITY OK 32 16 26 18 / 50 40 60 10
HOBART OK 33 16 23 16 / 50 50 60 10
WICHITA FALLS TX 38 20 25 19 / 100 60 70 10
GAGE OK 24 11 23 14 / 90 60 50 10
PONCA CITY OK 26 13 26 16 / 100 20 30 20
DURANT OK 39 21 28 21 / 100 60 80 20
&&
.OUN WATCHES/WARNINGS/ADVISORIES...
OK...WINTER WEATHER ADVISORY UNTIL 3 PM CST THIS AFTERNOON FOR OKZ007-
008-012-013-018>020.
WINTER WEATHER ADVISORY UNTIL 6 AM CST MONDAY FOR OKZ004>006-
009>011-014>017.
WINTER WEATHER ADVISORY UNTIL 6 PM CST MONDAY FOR OKZ021>048-
050>052.
TX...WINTER WEATHER ADVISORY UNTIL 6 PM CST MONDAY FOR TXZ083>090.
&&
$$
99/99/14
AREA FORECAST DISCUSSION...UPDATED
NWS NORMAN OK
1040 AM CST SUN FEB 22 2015
.UPDATE...
SNOW CONTINUES ACROSS PARTS OF NORTHERN OK THIS MORNING. THIS
SHOULD CONTINUE INTO EARLY AFTN BEFORE DIMINISHING SO WILL EXTEND
THE WINTER WEATHER ADVISORY TO 21Z. WITH ONLY LIGHT SNOW OCCURRINGIN
NW PARTS OF AREA WILL ALSO CHANGE THE WINTER STORM WARNING TO AN
ADVISORY.
AREA OF RAIN/SLEET/SNOW WILL CONTINUE TO MOVE ACROSS PARTS OF
SOUTHERN OKLAHOMA AND WESTERN NORTH TEXAS THIS AFTERNOON. ISOLATED
THUNDER HAS BEEN SEEN IN THIS AREA BUT THE OCCURRENCE OF THUNDER
IN THE FA HAS DIMINISHED OVER THE PAST HOUR OR SO. THERE STILL MAY
BE A FEW CLAPS OF THUNDER THIS AFTERNOON.
COLD AIR WILL CONTINUE TO MOVE ACROSS THE REGION TODAY CONTINUING
TO CAUSE FALLING TEMPERATURES THIS AFTERNOON. WINDY CONDITIONS
WILL ALSO CONT THIS AFTN WITH OCCASIONAL GUSTS OVER 40 MPH IN
WESTERN PARTS OF THE AREA ALONG AND SOUTH OF I-40. THE WINDY
CONDITIONS COMBINED WITH THE COLD TEMPERATURES WILL ALSO CONTINUE
TO CAUSE COLD WIND CHILLS ACROSS THE AREA WITH MUCH OF THE AREA
DROPPING TO THE TEENS AND SINGLE DIGITS. A FEW LOCATIONS COULD
ALSO HAVE WIND CHILLS AROUND ZERO DEGREES. UPDATES OUT SOON.
&&
.PREV DISCUSSION... /ISSUED 549 AM CST SUN FEB 22 2015/
AVIATION...
A STRONG COLD FRONT IS MOVING THROUGH THE AREA WITH GUSTY NORTH
WINDS AND IFR-MVFR CIGS ACROSS NORTHERN OKLAHOMA... WHICH WILL
SPREAD INTO SOUTHERN OKLAHOMA AND NORTH TEXAS AS THE FRONT MOVES
THROUGH. MVFR CIGS AND GUSTY WINDS WILL SPREAD INTO SOUTHERN
OKLAHOMA AND NORTH TEXAS AS THE FRONT PROGRESSES. AREAS OF SNOW
ARE OCCURRING IN NORTHERN AND WESTERN OKLAHOMA WITH MORE
RAIN/SNOW/SLEET EXPECTED TO SPREAD INTO NORTH TEXAS AND SOUTHERN
OKLAHOMA FROM SOUTHWESTERN TEXAS THROUGH THE DAY. WIDESPREAD MVFR
OR LOWER CIGS WILL PERSIST THROUGH THE FORECAST PERIOD.
PREV DISCUSSION... /ISSUED 442 AM CST SUN FEB 22 2015/
DISCUSSION...
WINTER WEATHER ROUND NUMBER 1 IS UNDERWAY CURRENTLY IN NORTHWEST
OKLAHOMA... BUT NOT WITHOUT COMPLICATIONS. FIRST IS THE RELATIVELY
SLOW ARRIVAL OF THE COLD AIR BRINGING A LATER TRANSITION TO
SNOW... AND SECOND IS THE SPLIT MESOSCALE BANDING THAT HAS
DEVELOPED WITH ONE BAND IN SOUTHWEST KANSAS NEAR DODGE CITY AND
SECOND FROM DUMAS TEXAS TO WATONGA TO GUTHRIE. WITH THE SOUTHERN
BAND PERSISTING AND MOVING EAST... THIS WARRANTS EXPANDING THE
WINTER WEATHER ADVISORY INTO NORTH CENTRAL OKLAHOMA WHERE TRENDS
AND HRRR SUGGEST AN INCH OF SNOW OR SO MAY FALL. ALTHOUGH THE
SPLIT MESOSCALE BANDS HAVE FORMED ON EITHER SIDE OF THE WARNING IN
NORTHWEST OKLAHOMA... WILL NOT DOWNGRADE NOW AS SOME DECENT
SNOWFALL IS STILL POSSIBLE DEPENDING ON HOW THE BANDS EVOLVE
ALTHOUGH RIGHT NOW IT LOOKS LIKE THE HEAVIEST SNOW THIS MORNING
MAY BE NEAR THE ARNETT-TALOGA-WATONGA LINE.
ROUND NUMBER 2 WILL BEGIN TO DEVELOP ACROSS TEXAS AND SPREAD INTO
THE AREA LATER THIS MORNING. COOLING CLOUD TOPS ARE BEING OBSERVED
IN SOUTHWEST TEXAS RIGHT NOW AND RADARS ARE BEGINNING TO DETECT
SOME DEVELOPING ECHOES ACROSS WEST TEXAS. PRECIPITATION WILL
BECOME MORE WIDESPREAD AND THEN SPREAD INTO SOUTHERN PART OF OUR
FORECAST AREA TODAY. AS THE COLD AIR CONTINUES TO SPREAD SOUTH...
PRECIPITATION WILL MIX WITH AND THEN CHANGE TO SNOW THIS AFTERNOON
IN THE SOUTH. AS WAVE NUMBER 2 EXITS TONIGHT... WAVE NUMBER 3
MOVES IN FROM THE WEST AND SPREADS ACROSS THE AREA LATE TONIGHT
AND MONDAY. MODELS SUGGEST MESOSCALE BANDING WILL BE POSSIBLE
AGAIN MAINLY HIGHLIGHTING SOUTHERN OKLAHOMA... BUT AS USUAL THERE
IS SOME UNCERTAINTY ON THE SPECIFIC PLACEMENT OF ANY SMALL SCALE
FEATURES THAT DEVELOP.
RAIN/SNOW WILL BE THE PRIMARY PRECIPITATION TYPES THROUGH THESE
PRECIPITATION EVENTS... BUT SLEET WILL ALSO BE POSSIBLE. IN THE
SOUTH TODAY... THERE MAY BE ENOUGH OF A WARM LAYER TO PARTIALLY
MELT THE SNOW AS IT FALLS BEFORE REFREEZING IN THE COLD LAYER
BELOW. BUT THERE ARE ALSO SUGGESTIONS THAT WE MAY LOSE MOISTURE IN
THE DENDRITIC GROWTH ZONE REGIONS ALOFT AT TIMES THROUGH THIS
EVENT SUGGESTING SUPERCOOLED WATER FREEZING IN THE COLD LAYER.
ALTHOUGH FREEZING RAIN IS NOT COMPLETELY OUT OF THE QUESTION IN
THE SOUTH TODAY... DEPTH OF FORECAST LOW-LEVEL COLD LAYER
INDICATES THAT SLEET IS MORE LIKELY.
THERE WILL BE A BREAK IN THE PRECIPITATION CHANCES TUESDAY AND
WEDNESDAY WITH WARMER TEMPERATURES WEDNESDAY. THEN MORE COLD AIR
ARRIVES AND PRECIPITATION CHANCES REDEVELOP WEDNESDAY
NIGHT/THURSDAY. ALTHOUGH THERE IS AGREEMENT IN THE GENERAL PATTERN
SHIFT... THERE REMAIN DIFFERENCE IN THE MEDIUM RANGE MODELS ON THE
FINER DETAILS WHICH ARE SUFFICIENT ENOUGH TO GIVE LOW CONFIDENCE
IN THE LATER PERIODS OF THE FORECAST.
&&
.PRELIMINARY POINT TEMPS/POPS...
OKLAHOMA CITY OK 32 16 26 18 / 50 40 60 10
HOBART OK 33 16 23 16 / 50 50 60 10
WICHITA FALLS TX 38 20 25 19 / 100 60 70 10
GAGE OK 24 11 23 14 / 90 60 50 10
PONCA CITY OK 26 13 26 16 / 100 20 30 20
DURANT OK 39 21 28 21 / 100 60 80 20
&&
.OUN WATCHES/WARNINGS/ADVISORIES...
OK...WINTER WEATHER ADVISORY UNTIL 3 PM CST THIS AFTERNOON FOR OKZ007-
008-012-013-018>020.
WINTER WEATHER ADVISORY UNTIL 6 AM CST MONDAY FOR OKZ004>006-
009>011-014>017.
WINTER WEATHER ADVISORY UNTIL 6 PM CST MONDAY FOR OKZ021>048-
050>052.
TX...WINTER WEATHER ADVISORY UNTIL 6 PM CST MONDAY FOR TXZ083>090.
&&
$$
25/09
AREA FORECAST DISCUSSION
NWS CORPUS CHRISTI TX
348 PM CST SUN FEB 22 2015
.SHORT TERM (TONIGHT THROUGH MONDAY NIGHT)...FRONTAL BOUNDARY HAS
REMAINED STALLED JUST NORTH OF THE FORECAST AREA THIS AFTERNOON.
LATEST MSAS ANALYSIS SHOWS AREAS OF STRONG PRESSURE RISES BEHIND
THE FRONT SHIFTING TOWARD CENTRAL TEXAS INTO THE HILL COUNTRY. THIS
CORRESPONDS TO LOCATION OF TEMPERATURES IN THE 40S. EXPECT THE FRONT
WILL BEGIN TO ADVANCE SOUTHWARD LATE THIS AFTERNOON AND SURGE TO
THE SOUTH THIS EVENING. WENT CLOSE TO THE SREF/HRRR/3KM TECH WRF
AND ECMWF WITH TIMING OF THE FRONT...PUSING INTO THE COASTAL WATERS
BETWEEN 04-06Z. HRRR SHOWS THE POSSIBILITY OF CONVECTION FORMING
OVER THE HIGH TERRAIN IN NORTHEAST MEXICO AHEAD OF THE COLD FRONT
AND MOVING SOUTHEAST TOWARD THE RIO GRANDE. BUT EXPECT AIR MASS TO
BE CAPPED AND WILL NOT MENTION THUNDER IN THE FORECAST AT THIS
TIME. THERE WILL BE A PERIOD OF FOG POSSIBLE ALONG THE COAST BEFORE
FRONTAL PASSAGE. MODEST ISENTROPIC LIFT WILL OCCUR IN THE 285-300K
LAYER LATE TONIGHT THROUGH MONDAY. WILL SHOW POPS AROUND 50 PERCENT
FOR TONIGHT WITH LIKELY POPS FOR MONDAY. LOW LEVEL COLD AIR ADVECTION
WILL CONTINUE DURING THE DAY MONDAY. DIURNAL TREND MAY BE SLOWLY
DOWNWARD MOST OF THE DAY. ISENTROPIC LIFT WILL DIMINISH FROM WEST
TO EAST MONDAY NIGHT WITH DECREASING POPS. LOW TEMPS WILL REACH
DOWN INTO THE 30S MONDAY NIGHT BUT EXPECT IT WILL REMAIN ABOVE
FREEZING AT THIS TIME.
&&
.MARINE (TONIGHT THROUGH MONDAY NIGHT)...COLD FRONT WILL REACH
THE BAYS AND NEARSHORE WATERS A LITTLE EARLIER THIS EVENING. PUT
THE START TIME FOR THE SCA FOR TONIGHT AT 04Z. STRONG NORTH TO
NORTHEAST WINDS WILL PERSIST INTO MONDAY NIGHT FOR THE GULF WATERS.
EXTENDED SCA FOR THE BAYS THROUGH THE DAY MONDAY AND MONDAY EVENING
FOR THE GULF WATERS.
&&
.LONG TERM (TUESDAY THROUGH SATURDAY NIGHT)...ZONAL FLOW ACROSS THE
SOUTHERN CONUS THIS FORECAST PERIOD WILL RESULT IN A MIX OF WEATHER
CONDITIONS FOR THIS UPCOMING WEEK. ISENTROPIC LIFT WILL MAINTAIN CHC
OF LIGHT RAIN THROUGH EARLY WEDNESDAY BEFORE DRIER AIR MOVES IN AND
A SLIGHT WARMING TREND COMMENCES. TEMPS ON TUE WILL STRUGGLE TO GET
OUT OF THE 40S DUE TO THICK CLOUD COVER...ALTHOUGH A FEW 50S ARE
POSSIBLE ALONG THE COAST AND OUT WEST. NEXT REINFORCING SURGE OF
HIGH PRESSURE ARRIVES EARLY WEDNESDAY WITH SCA CONDITIONS OCCURING
ON WED...HOWEVER...ABUNDANT SUNSHINE WILL ALLOW TEMPS TO REACH THE
60S BOTH WED-THU. NEXT FRONT ARRIVES LATE THURSDAY WITH A MODERATE
OFFSHORE FLOW DEVELOPING IN ITS WAKE. THE FRONT WILL DROP TEMPS BACK
INTO THE 40S-50S FOR FRIDAY BENEITH OVC SKIES. COULD BE A FEW
SHOWERS AS MOIST SOUTHERLY LOW LVL FLOW OVERRIDES THE COOL BOUNDARY
LAYER. THE COOL AIR WONT LAST LONG AS A DEEP TROUGH BEGINS TO TAKE
SHAPE ACROSS THE DESERT SW DRAWING A WARM FRONT BACK THROUGH THE
AREA SAT. TEMPS ON SAT WILL WARM BACK INTO THE LOW TO MID 60S SAT
WITH 70S EXPECTED SUNDAY.
&&
.PRELIMINARY POINT TEMPS/POPS...
CORPUS CHRISTI 47 48 38 50 43 / 50 70 40 20 30
VICTORIA 43 44 35 46 38 / 50 70 40 20 40
LAREDO 46 46 39 54 44 / 50 50 20 10 10
ALICE 45 46 37 50 41 / 50 70 40 20 30
ROCKPORT 47 50 39 50 43 / 50 70 40 30 40
COTULLA 42 43 35 50 40 / 50 50 30 10 10
KINGSVILLE 48 48 37 50 43 / 50 70 40 20 30
NAVY CORPUS 49 51 39 51 45 / 50 70 40 30 40
&&
.CRP WATCHES/WARNINGS/ADVISORIES...
TX...RIP CURRENT RISK UNTIL 6 PM CST THIS EVENING FOR THE FOLLOWING
ZONES: ARANSAS...CALHOUN...KLEBERG...NUECES.
GM...SMALL CRAFT ADVISORY FROM 10 PM THIS EVENING TO MIDNIGHT CST
MONDAY NIGHT FOR THE FOLLOWING ZONES: COASTAL WATERS FROM
BAFFIN BAY TO PORT ARANSAS OUT 20 NM...COASTAL WATERS FROM
PORT ARANSAS TO MATAGORDA SHIP CHANNEL OUT 20 NM...WATERS
FROM BAFFIN BAY TO PORT ARANSAS FROM 20 TO 60 NM...WATERS
FROM PORT ARANSAS TO MATAGORDA SHIP CHANNEL FROM 20 TO 60
NM.
SMALL CRAFT ADVISORY FROM 10 PM THIS EVENING TO 6 PM CST MONDAY
FOR THE FOLLOWING ZONES: BAYS AND WATERWAYS FROM BAFFIN BAY
TO PORT ARANSAS...BAYS AND WATERWAYS FROM PORT ARANSAS TO
PORT O`CONNOR.
&&
$$
TMT/89...SHORT TERM
JM/75...LONG TERM
FORECAST DISCUSSION FOR ROUTINE AFTERNOON FORECAST ISSUANCE
.SHORT TERM...TONIGHT AND MONDAY
ISSUED AT 231 PM CST SUN FEB 22 2015
THE LATEST RAP ANALYSIS AND SATELLITE/RADAR IMAGERY SHOW ARCTIC HIGH
PRESSURE DRIFTING SOUTHEAST OVER THE NORTHERN GREAT PLAINS EARLY
THIS AFTERNOON. THOUGH COLD ADVECTION IS ONGOING...HEATING HAS
SERVED TO STEEPEN LOW LEVEL LAPSE RATES...WHICH TRIGGERED A CU FIELD
TO FORM LATE IN THE MORNING. DRY AIR IS WINNING OUT THIS AFTERNOON
AS EVIDENT BY THE CU FIELD DIMINISHING. ONLY CLEAR AND BITTERLY
COLD CONDITIONS EXIST UPSTREAM...SO FORECAST CONCERNS INCLUDE TEMPS
AND WIND CHILLS THROUGH MONDAY.
TONIGHT...STRONG ARCTIC HIGH PRESSURE WILL BE SLIDING SOUTHEAST FROM
THE NORTHERN GREAT PLAINS TO CENTRAL IOWA. LOSS OF DIURNAL HEATING
WILL CAUSE ANY LINGERING CU TO DISSIPATE BY EARLY THIS
EVENING...WHICH WILL LEAVE CLEAR SKIES FOR MUCH OF THE NIGHT.
BECAUSE THE ARCTIC HIGH WILL DROP SOUTHWEST OF THE REGION...BOTH
STATISTICAL AND NUMERICAL GUIDANCE POINT TOWARDS WINDS REMAINING IN
THE 5 TO 10 KT RANGE THIS EVENING...BEFORE DIMINISHING SOME
OVERNIGHT. SOME POTENTIAL FOR DECOUPLING OVER N-C WISCONSIN AS
BOUNDARY LAYER WINDS LIGHTEN. AS A RESULT...THINK TEMPERATURES HAVE
A CHANCE TO TUMBLE LATE TONIGHT. THIS MAKES FOR A DILEMMA IN TERMS
OF HEADLINE DECISIONS. IF WINDS REMAIN IN THE 4-5 KT RANGE...SOME
PLACES LIKE ANTIGO AND RHINELANDER COULD REACH WIND CHILL WARNING
CRITERIA FOR A PERIOD LATE TONIGHT INTO MONDAY MORNING. THINK
WARNING CONDITIONS WILL NOT BE WIDESPREAD ENOUGH DUE TO WINDS
DROPPING OFF. SO WILL STICK WITH THE ADVISORY THROUGH THE NIGHT AND
CONTINUE TO MENTION THAT SOME SPOTS WILL HIT WARNING CRITERIA. IF
WINDS DO DROP OFF...TEMPS 25 TO 30 BELOW ARE POSSIBLE.
MONDAY...HIGH PRESSURE WILL BE DRIFTING TO THE MID-MISSISSIPPI
VALLEY WHILE THE NEXT CLIPPER WILL REACH NORTHERN MINNESOTA LATE IN
THE AFTERNOON. A TIGHTENING PRESSURE GRADIENT BETWEEN THESE
FEATURES WILL CAUSE WINDS TO SWING AROUND TO THE SOUTHWEST AND
BECOME GUSTY IN THE AFTERNOON. BUT THE SOUTHWEST WINDS WILL ALSO
HELP MODERATE THE BITTERLY COLD AIRMASS. WIND CHILLS WILL BE
WARMING ABOVE ADVISORY CRITERIA BY LATE IN THE MORNING SO THE ENDING
TIME LOOKS ABOUT RIGHT. THOUGH CIRRUS WILL BE INCREASING IN THE
AFTERNOON...HIGHS WILL WARM INTO THE UPPER SINGLE DIGITS TO THE
LOWER TEENS.
.LONG TERM...MONDAY NIGHT THROUGH SUNDAY
ISSUED AT 231 PM CST SUN FEB 22 2015
OVERALL UPPER LEVEL PATTERN CONSISTING OF A WESTERN RIDGE AND
EASTERN TROUGH WILL REMAIN FOR MOST OF THE PERIOD...ALTHOUGH THERE
ARE HINTS THAT THE WESTERN RIDGE MAY REORGANIZE FURTHER WEST OVER
THE PACIFIC WHILE FLOW OVER THE UNITED STATES TAKES ON MORE OF AN
APPEARANCE OF SPLIT FLOW. THIS CHANGE DOES NOT LOOK LIKE IT WILL
DO MUCH TO REVERSE OUR TREND OF SEEING TEMPS WELL BELOW
NORMAL. FOR NOW...ONLY TUESDAY LOOKS TO SEE HIGHS RELATIVELY NEAR
NORMAL...WITH A RETURN TO COLD WEATHER AFTER A FRONT MOVES
THROUGH.
THE PRIMARY CHANCE FOR MEASURABLE SNOW LOOKS TO BE MONDAY NIGHT
AND TUESDAY AS A LOW PRESSURE PASSES NORTH THROUGH ONTARIO...WITH
AN ATTACHED COLD FRONT PUSHING ACROSS THE AREA ONCE AGAIN. GUIDANCE
CONTINUES TO LIKE OUR FAR NORTH FOR THE BEST CHANCE AND AMOUNTS OF
SNOW...TO BE EXPECTED AS THE LOW PASSES SOME DISTANCE TO OUR NORTH
AND EAST. HOWEVER...THE GFS AND TO SOME EXTENT THE GEM PROVIDE
BETTER MOISTURE AND LIFT...AND BRING AN INCH OR TWO OF SNOW DOWN
THROUGH A LARGE PORTION OF THE NORTHEAST QUARTER OF WISCONSIN. IT
IS WORTH NOTING THAT THE GFS ENSEMBLE CONTINUES TO NOT BE AS
ENAMORED OF THIS IDEA AS THE DETERMINISTIC RUN. IN GENERAL WILL
FOLLOW SUIT...PUTTING THE HIGHEST POPS AND ACCUMULATIONS IN FAR
NORTHERN WISCONSIN...BUT WILL PAY SOME DEFERENCE TO THE NORTH
AMERICAN MODELS AND THEIR PLAUSIBLE...IF NOT AS CONVINCING...IDEA
OF MORE SNOW FURTHER TO THE SOUTH AND WEST WITH CHANCE POPS
TUESDAY MORNING.
ALONG WITH THIS SNOW...OUR POSITION BETWEEN THIS ONCOMING
LOW AND THE HIGH RESPONSIBLE FOR OUR MOST RECENT COLD PLUNGE WILL
RESULT IN GUSTY SOUTHWEST WINDS MONDAY NIGHT INTO TUESDAY. THIS
COULD CREATE SOME BLOWING AND DRIFTING OF ANY SNOW THAT MAY
FALL...EVEN IF AMOUNTS ARE NOT PARTICULARLY HIGH. GUIDANCE IS
UNANIMOUS IN STRONG 50 TO 65 KNOT WINDS AT RELATIVELY LOW ALTITUDE
VERY EARLY TUESDAY MORNING. SOUNDINGS IN BUFKIT SHOW POTENTIAL
GUSTS TO 20-30 KTS...AND GUSTS EVEN A LITTLE HIGHER ARE NOT OUT OF
THE QUESTION...THOUGH THIS SCENARIO WOULD NEED BETTER MIXING TO
COME TO FRUITION.
AFTERWARDS...HIGH PRESSURE SETTLES OVER THE AREA BRINGING DRY
WEATHER THROUGH SATURDAY. IN WHAT SURELY IS BEGINNING TO SOUND ALL
TOO FAMILIAR...WE WILL SEE ANOTHER SHOT OF WELL BELOW NORMAL
TEMPERATURES. THE COLDEST PERIOD LOOKS TO BE TUESDAY NIGHT THROUGH
THURSDAY. HIGHS ON WEDNESDAY LOOK TO BE MIRED IN THE SINGLE DIGITS
FOR MOST...WITH SUBZERO LOWS ON TAP TUESDAY AND WEDNESDAY NIGHT.
A SLOW MODERATION IN TEMPERATURES IS EXPECTED THROUGH THE WEEKEND.
ANOTHER CHANCE FOR PRECIPITATION EMERGES DURING THE WEEKEND...BUT
WITH A GOOD BIT OF UNCERTAINTY IN THE NATURE OF THE UPPER
FLOW...WILL NOT SPECULATE ON THE DETAILS FOR NOW.
&&
.AVIATION...FOR 18Z TAF ISSUANCE
ISSUED AT 1127 AM CST SUN FEB 22 2015
CUMULUS FORMATION WILL CONTINUE THROUGH MID-AFTERNOON
AND WILL PRODUCE BROKEN MVFR CIGS FOR A PERIOD OVER NORTH-CENTRAL
WISCONSIN. CENTRAL AND NORTHEAST WISCONSIN MAY ALSO SEE BRIEF MVFR
CIGS THIS AFTERNOON AS WELL. CLOUDS WILL DISSIPATE LATE THIS
AFTERNOON WHICH WILL LEAD TO CLEAR CONDITIONS TONIGHT. SOUTHWEST
WINDS WILL BE STRENGTHENING ON MONDAY UNDER INCREASING CIRRUS.
&&
.GRB WATCHES/WARNINGS/ADVISORIES...
WIND CHILL ADVISORY FROM 9 PM THIS EVENING TO 10 AM CST MONDAY
FOR WIZ013-020>022-031-037>040-045-048>050-073-074.
WIND CHILL ADVISORY UNTIL 10 AM CST MONDAY FOR WIZ005-010>012-
018-019-030-035-036.
&&
$$
SHORT TERM.....MPC
LONG TERM......LUCHS
AVIATION.......MPC