Forecast Discussions mentioning any of
"HRRR" "RAP" "RR" "RUC13" "RUC" received at GSD on 02/15/14
AREA FORECAST DISCUSSION
NWS SACRAMENTO CA
105 PM PST Thu Feb 13 2014
.Synopsis...
Unsettled weather is expected into next week. A fetch of Pacific
moisture will bring showers to the area through tomorrow, mainly
north of I-80. More widespread precipitation is expected with another
system this weekend. A colder storm is possible next Tuesday into
Wednesday.
&&
A broad and extensive tap of moisture off the East Pacific with
near zonal flow continues as seen on water vapor satellite
imagery this morning. The fetch extends from around Hawaii and
reaches the West Coast centered at the CA/OR border. While fairly
impressive- looking on water vapor, the blended total PWAT product
shows only around 1" PWAT reaching the NorCal coast, with about
1.2" further offshore. The NAM and GFS were a little overdone on
their PWAT estimates early today, but it looks like they are now
in line with the satellite estimates. Area radars show an area of
showers which has moved inland within the last few hours.
Expecting rain to be mostly limited to the higher terrain today
given the due westerly flow shadowing the Valley, although the
latest HRRR runs have been indicating some convective precip in
the Sac Valley this afternoon from around Yuba City northward.
Have handled this in the latest forecast update with a mention of
scattered showers. Can`t rule out a few isolated showers in the
Sac Metro area, though it doesn`t appear very likely at this
point. Recent aircraft soundings show that the freezing level is
over 9000 feet this morning, so most Sierra locations will see
only rain showers.
Have updated the forecast for today/tonight to bring in line with
latest model trends. For conditions beyond today/tonight, see the previous
discussion below. -DVC
.Previous discussion...issued 506 AM PST...
Wet, unsettled weather through this week as the moisture plume
from Hawaii continues to take aim at NorCal. Mountains of Shasta
County will get the brunt of rain totals peaking between 1-2
inches through Friday night. Rain over the Coastal range and
Sierra will range from around a quarter of an inch up to a half
inch. Rain totals around Redding and Red Bluff region will range
from several hundredths of an inch up to a quarter of an inch. Any
rain totals between Red Bluff and the Sac Metro region will likely
only be a few hundredths. Some patchy fog may develop this morning
south of the Sac Metro region but is not expected to be dense or
widespread due to the increasing cloud cover.
Another system moves in this weekend that is forecast to bring
precipitation farther southward as a trough digs towards
Central CA. This time, widespread wetter conditions are expected
across the higher terrain (Coastal, Northern, Sierra). This storm
will bring some colder air aloft allowing snow levels to dip down
towards 5000 ft by early Sunday morning but most of the snow
accumulation will occur above 6000 feet. Accumulations will range
from a few inches up to almost a foot at the highest elevations
across the Sierra. Rain totals below 5000 ft will range from a few
hundredths in the valley up to 1-1.5 inches across foothills and
slopes. Daytime highs will be slightly cooler than Thursday &
Friday while overnight lows remain fairly similar. JBB
.Extended Discussion (Monday through Thursday)
Monday looks mainly dry as upper ridge over the west coast begins
to fatten. Daytime highs Monday should come in a few degrees above
normal under a variable high cloudiness as indicated by GFS upper
level RH progs. Upper ridge fattens on Tuesday with all models
indicating Pacific frontal system moving into Pacific northwest
and Norcal Tuesday afternoon. GFS Predicted moisture feed with
this cooler system is moderate at about .8 inches TPW. ECMWF
indicating a somewhat wetter system with higher QPF. Moist Pacific
flow will keep precipitation threat going for most of the CWA into
Wednesday. Snow levels will continue to fall Wednesday as colder
air filters into the region. Some Sierra foothills could see
snowfall as snow levels lower below 3000 feet Wednesday afternoon.
QPF values continue to vary between models but with low snow
levels...mountain and foothill impacts are likely. Models vary
going into the end of next week. All extended models indicating
northwest flow aloft with GFS and ECMWF modeling a shortwave
dropping out of western Canada for a continued shot of low
elevation snow showers into Thursday.
&&
.Aviation...
Pacific frontal band moving through Pacific northwest and NORCAL
with light precipitation moving slowly southward. For the
Sacramento valley...MVFR local IFR cigs and visibility with light
rain and fog. IFR cigs over surrounding mountains. VFR Northern
San Joaquin valley and surrounding mountains except MVFR and local
IFR in the valley in fog through about 20z. South winds to 15
knots with gusts to 45 knot over higher Sierra elevations.
&&
.STO Watches/Warnings/Advisories...
None.
&&
$$
AREA FORECAST DISCUSSION
NWS DENVER/BOULDER CO
1014 AM MST THU FEB 13 2014
.UPDATE...
&&
.SHORT TERM...WEB CAMS AND RADAR SHOWING LIGHT SNOW CONTINUING
ACROSS THE MOUNTAINS...CONCENTRATED ALONG THE CONTINENTAL DIVIDE
OF GRAND COUNTY. THERE MAY ALSO BE SOME LIGHT SNOW IN THE MOUNTAIN
VALLEYS AS WELL AS THE HIGHER FOOTHILLS. WINDS WERE ALSO GUSTY ACROSS
THE HIGHER MOUNTAINS AS WELL AS IN AND NEAR THE FOOTHILLS WITH
SOME GUSTS AROUND 50 MPH IN WIND PRONE AREAS. LATEST WATER VAPOR
LOOPS INDICATING SOME DRYING MOVING INTO NORTHWEST COLORADO WITH
ANOTHER BATCH OF MOISTURE PUSHING INTO UTAH. SO THERE MAY SOME
DECREASE IN THE SNOW EARLY THIS AFTERNOON AS THE DRYING MOVES
ACROSS THE MOUNTAINS...BUT SHOULD INCREASE AGAIN DURING THE
AFTERNOON WHEN THE MOISTURE INCREASES. THERE IS SOME WARM AIR
ADVECTION WHICH WILL OFFSET THE DECENT LAPSE RATES AND COULD LIMIT
THE SNOW ACCUMULATION. STILL...MOUNTAIN AREAS SHOULD SEE ANOTHER
3 TO 7 INCHES BY 06Z WITH GUSTY WINDS PRODUCING AREAS OF BLOWING
SNOW AND REDUCED VISIBILITIES. ONGOING ADVISORY FOR MOUNTAINS
STILL LOOKS REASONABLE. WARM AIR ADVECTION INCREASES OVERNIGHT
WITH SOME DECREASE IN MOISTURE. SNOW TO DECREASE AS A RESULT.
LATEST RAP AND HRRR INDICATE WIND GUSTS INCREASING BY 18Z ALONG
FOOTHILLS AS SURFACE GRADIENT INCREASES. THUS...COULD SEE SOME
GUSTS AROUND 60 MPH IN WIND PRONE AREAS THIS AFTERNOON. GRADIENT
DECREASES THIS EVENING WITH DECREASING WINDS. SOME LIGHT
PRECIPITATION POSSIBLE ACROSS FAR EASTERN PLAINS OVERNIGHT WITH
APPROACHING WEAK FRONT AND JET ACROSS PLAINS.
.AVIATION...CURRENT TAF TRENDS STILL LOOK REASONABLE. WESTERLY
WINDS HAVE SPREAD ACROSS THE AREA AIRPORTS...THOUGH A BIT MORE
SOUTHWEST AT KDEN AND KAPA. STILL EXPECTING A SHIFT TOWARD THE
NORTHWEST BY 21Z AS THE NORTHWESTERLIES MIX TO THE SURFACE. SOME
GUSTS AROUND 20 KTS POSSIBLE AT KDEN AND KAPA THROUGH THE
AFTERNOON WITH GUSTS TO 30 KTS AT KBJC. WEAK DRY FRONT STILL
EXPECTED TO MOVE ACROSS THE AREA AFTER 08Z WITH THE NORTHWEST
WINDS BECOMING A BIT MORE NORTHERLY. VFR TO CONTINUE WITH CEILINGS
ABOVE 12000 FEET AGL.
&&
.PREV DISCUSSION... /ISSUED 329 AM MST THU FEB 13 2014/
SHORT TERM...PACIFIC MOISTURE IN NORTHWEST FLOW CONTINUES TO DROP
SNOW OVER THE HIGH COUNTRY THIS MORNING. SEEMS AS MOUNTAIN TOP
FLOW HAS SWITCHED TO A MORE WESTERLY DIRECTION EARLIER WHICH HAS
ALLOWED THE MOUNTAINS OF SUMMIT...PARK...GILPIN AND CLEAR CREEK
COUNTIES TO SEE HEAVIER SNOW EARLIER. THEREFORE HAVE MOVED UP THE
TIMING OF THE WINTER WEATHER ADVISORY TO START NOW. EXPECT ANOTHER
5 TO 10 INCHES TO FALL TODAY OVER THE HIGH MOUNTAINS AND UP TO A
COUPLE INCHES OVER THE HIGH VALLEYS AND UPPER FOOTHILLS. THESE
SNOW AMOUNTS MAY BE A LITTLE ON THE TOP END HOWEVER AS WARM
ADVECTION WILL DECREASE SNOW TO LIQUID RATIOS. MAX TEMPERATURES IN
THE MOUNTAINS ARE EXPECT TO WARM INTO THE 30S WITH HIGH VALLEYS
SEEING UPPER 30S TO NEAR 40. MOISTURE WILL BE DECREASING TONIGHT
AS A 170 KT JET ALONG THE NORTHERN TO CENTRAL ROCKIES MOVES EAST
AND THE UPPER RIDGE BUILDS INTO THE GREAT BASIN. BUT STILL WILL
SEE LIGHT SNOW CONTINUE THROUGH MIDNIGHT.
ANOTHER DEVELOPMENT IN THE FAST CHANGING WEATHER PATTERN WE HAVE
TODAY IS TO CANCEL THE HIGH WIND WARNING OVER THE FOOTHILLS EARLY.
WINDS PEAKED AROUND MIDNIGHT LAST NIGHT WITH A FEW READINGS IN THE
70 TO 80 MPH RANGE...AND HAVE SINCE DECREASED. WITH SURFACE
GRADIENTS DECREASING AND DOWNWARD QG MOTION DECREASING...SEE NO
OTHER MECHANISM TO PUSH THE SPEEDS BACK TO UP TO CRITERIA. STILL
EXPECT TO SEE GUSTS IN THE 50 TO 65 MPH RANGE THIS MORNING
HOWEVER.
THESE GUSTY WINDS HAVE MODERATED TEMPERATURES IN AND NEAR THE
FOOTHILLS OVERNIGHT WHICH WILL HELP WARM TEMPERATURES TODAY. MAX
READINGS IN THE 50S WITH READINGS CLOSE TO 60 NEAR THE FOOTHILLS.
AS THE 170 KT JET NEARS THE NORTHEAST CORNER OF THE STATE THIS
EVENING...THIS MAY HELP TO PRODUCE LIGHT SHOWERS OVER THE FAR
NORTHEAST PLAINS...BEGINNING AS RAIN THEN MIXING WITH SNOW AFTER
MIDNIGHT. AS THE AIRMASS WARMS AND MIXES...EXPECT TO SEE GUSTY
WEST WINDS SPREAD OVER THE PLAINS. A WEAK COLD FRONT IS EXPECTED
TO MOVE SOUTH ACROSS THE PLAINS AFTER MIDNIGHT TONIGHT TO TURN
WINDS MORE NORTHWEST TO NORTHERLY. LOWS WILL BE SLIGHTLY COOLER
THAN OVERNIGHT LAST NIGHT.
LONG TERM...FRIDAY THROUGH WEDNESDAY...
STRONG MID LEVEL FLOW WILL PERSIST ACROSS THE STATE THROUGH
SATURDAY. THIS WILL BRING ANOTHER THREAT OF HIGH WINDS TO THE
HIGHER MOUNTAINS AND FOOTHILLS STARTING AS EARLY AS FRIDAY
AFTERNOON. WARM ADVECTION WILL ALSO OCCUR IN EARNEST FRIDAY AND
FRIDAY NIGHT.
IN THE FOOTHILLS...LOOKS LIKE THIS WILL BE MAINLY A BRUTE FORCE
WIND EVENT WITH 50-60 KT CROSS MOUNTAIN FLOW STARTING LATE FRIDAY
AFTERNOON/EVENING. MOUNTAIN TOP STABLE LAYER IS SUGGESTED TO BE
RATHER LIMITED...BUT GIVEN STRENGTH OF WARM ADVECTION MODELS MAY
BE UNDERDOING THIS A BIT. LOW LEVEL GRADIENTS ARE SOMEWHAT LACKING
AS WELL SO NOT TOO CONCERNED AT THIS POINT THAT HIGH WINDS WILL
SPREAD ONTO THE ADJACENT PLAINS...BUT THEY WILL STILL BECOME GUSTY
FRIDAY NIGHT INTO SATURDAY MORNING IN TYPICAL CHINOOK FASHION.
THEREFORE...AT THIS TIME WILL BE ISSUING A HIGH WIND WATCH FOR THE
FOOTHILLS ONLY.
WITH REGARD TO MOUNTAIN SNOW...DECENT DRYING AND STABILIZATION
OCCURS FRIDAY MORNING SO ONLY LINGERING LIGHT SNOW/FLURRIES
EXPECTED IN THE MOUNTAINS. AFTER THAT...CONSIDERABLE MODEL
DISCREPANCY OCCURS BETWEEN THE 00Z GFS...NAM...AND ECMWF. BELIEVE
THE NAM IS CONSIDERABLY OVERDOING THE QPF IN THE HIGH COUNTRY
THROUGH SATURDAY GIVEN INCREASED STABILITY IN WARM ADVECTION
PATTERN...WHILE THE GFS MAY BE SLIGHTLY OVERDOING IT AND ECMWF
MIGHT BE A LITTLE ON THE DRY SIDE GIVEN THE STRONG FLOW. AT THIS
TIME...CONCEPTUAL MODEL WOULD SUGGEST THIS WOULD BE A RELATIVELY
HIGH POP/LOW QPF SNOW OVER THE HIGHER MOUNTAINS GIVEN THE
INCREASED STABILITY AND WARM ADVECTION. HOWEVER...THERE ARE HINTS
THAT LAPSE RATES IMPROVE A BIT LATE SATURDAY AFTERNOON/EVENING.
NOT SURE WHAT THIS IS COMING FROM SINCE WE ARE IN A WARM ADVECTION
PATTERN SO WILL MAINTAIN THE THOUGHT OF LIGHT SNOW MAINLY OVER THE
MOUNTAINS AT THIS POINT. COULD SEE A FEW SPRINKLES/LIGHT RAIN IN
VALLEY LOCATIONS BELOW 8500 FEET GIVEN TEMP PROFILES.
TEMPERATURE WISE...WILL WARM UP THE MOUNTAINS AND ESPECIALLY
MOUNTAIN VALLEYS WITH CLOUDS AND LITTLE/NO INVERSIONS EXPECTED
OVERNIGHT THROUGH SATURDAY. ON THE PLAINS...CANT GET TOO CARRIED
AWAY WITH HIGH TEMPS YET SINCE FRIDAY WILL BE POST FRONTAL...AND
YET ANOTHER WEAK SURGE POSSIBLE SATURDAY PER THE ECWMF. ON
SUNDAY...FULL EFFECTS OF RIDGING AND WARMING ARE EXPECTED WITH
READINGS PUSHING INTO THE 60S ON THE PLAINS.
NEXT WEATHER SYSTEM WILL LIKELY REACH THE MOUNTAINS BY SUNDAY
AFTERNOON WITH A GOOD BUT BRIEF SHOT OF SNOW FROM LATE IN THE DAY
THROUGH SUNDAY NIGHT...POSSIBLY REACHING ADVISORY CRITERIA WITH
SHORT BUT MODERATELY INTENSE PERIOD OF SNOW AND STRONG/GUSTY
WINDS.
DRY AND WARMER WEATHER EXPECTED ALL AREAS MONDAY AND
TUESDAY...BEFORE NEXT WEATHER SYSTEM APPROACHES THE REGION BY
WEDNESDAY.
AVIATION...VFR CONDITIONS OVER THE NEXT 24 HRS WITH BKN-SCT MID
AND UPPER LEVEL CLOUDS. DOWNSLOPING WINDS AFFECTING THE AREA
AIRPORTS ARE EXPECTED TO GO TO A MORE DRAINAGE PATTERN THROUGH THE
MORNING...THEN RETURN TO THE WESTERLY DOWNSLOPE DIRECTION IN THE
AFTERNOON. A COLD FRONT TONIGHT WILL HAVE LITTLE EFFECT EXCEPT FOR
SLIGHTLY COOLER TEMPERATURES AND TO TURN THE WESTERLY WINDS TO A
NORTHWEST TO NORTH DIRECTION.
&&
.BOU WATCHES/WARNINGS/ADVISORIES...
HIGH WIND WATCH FROM FRIDAY AFTERNOON THROUGH SATURDAY MORNING
FOR COZ035-036.
WINTER WEATHER ADVISORY UNTIL 11 PM MST THIS EVENING FOR COZ031-
033-034.
&&
$$
SHORT TERM...D-L
LONG TERM....BARJENBRUCH
AVIATION...D-L
AREA FORECAST DISCUSSION
NWS GRAND JUNCTION CO
1001 AM MST THU FEB 13 2014
.UPDATE...
ISSUED AT 1000 AM MST THU FEB 13 2014
THE FORECAST REMAINS ON TRACK THOUGH THE DETAILS ARE MESSY. SNOW
WILL CONTINUE OVER THE NORTHERN AND CENTRAL COLORADO MOUNTAINS AT
LEAST THROUGH FRIDAY NIGHT. SNOW LEVELS RISE TO AROUND 7000-7500
FT THIS AFTERNOON BEFORE DROPPING TO AROUND 5000 FT TONIGHT. SO
FOR THE NORTHERN-CENTRAL VALLEYS A RAIN/SNOW MIX THIS AFTERNOON
TRANSITIONING TO MOSTLY SNOW OVERNIGHT.
THE 12Z NAM AND RAP SHOW A FINGER OF THE JET PROVIDING SOME
ENHANCEMENT OVER THE FLATTOPS THIS LATE AFTERNOON AND EARLY
EVENING. SO SNOW AMOUNTS MAY BE GREATER THERE THAN PREVIOUSLY
FORECAST.
NORTHERN COLORADO SNOW ACCUMULATIONS ARE EXPECTED TO DIMINISH ON
FRIDAY BUT NOT END. ANOTHER FEW INCHES EXPECTED TO ACCUMULATE
THROUGH FRIDAY NIGHT. THE 7 INCHES PRODUCED BY THE NAM FOR FRI-
FRI NIGHT SEEMS UNLIKELY AS 700MB CLIMB TO -1C.
FOR ALL MTNS BREEZY TO WINDY CONDITIONS CONTINUE THROUGH FRIDAY
NIGHT WITH 700-600MB WINDS PROGGED TO REMAIN 40-50KTS
NORTH/30-40KTS SOUTH.
&&
.SHORT TERM...(TODAY THROUGH FRIDAY)
ISSUED AT 420 AM MST THU FEB 13 2014
STRONG WESTERLY FLOW ACROSS THE EASTERN PACIFIC WILL CONTINUE TO
CARRY DEEP MOISTURE ACROSS THE TOP OF A BROAD/FLAT RIDGE OFF THE
SOUTHERN CA/BAJA COAST. THE MAIN CHANNEL OF THIS MOIST FLOW WILL
REMAIN OVER THE PACIFIC NORTHWEST STATES AND ACROSS THE NORTHERN
ROCKIES. HOWEVER OUR FORECAST AREA WILL BE ON THE SOUTHERN EXTENT
OF THIS STREAM.
THE STRONG WESTERLIES ARE ASSOCIATED WITH THE UPPER LEVEL JET
STREAM WHICH WILL CONTINUE TO MORE OR LESS TRAVERSE THE NORTHERN
TIER STATES. WHILE THE CORE OF THIS JET STREAM WILL ALSO REMAIN TO
OUR NORTH...SOME JET ENERGY WILL CONTINUE TO SAG ACROSS OUR
NORTHERN BORDER. THEREFORE OROGRAPHIC SNOW WILL PERSIST OVER THE
NORTHERN AND CENTRAL COLORADO MOUNTAINS TODAY AND TONIGHT...WITH
SOME LET-UP ON FRIDAY. WILL GO AHEAD AND LET THE PRESENT
HIGHLIGHTS RIDE. WHILE SNOW WILL CONTINUE TO BE LIKELY THROUGH
FRIDAY OVER THE HIGHER PEAKS OF THESE MOUNTAINS...IT WILL DIMINISH
IN INTENSITY AS WE BECOME A LITTLE MORE INFLUENCED BY THE BROAD
RIDGE TO OUR SOUTHWEST. IN ADDITION TO THE SNOW...GUSTY WEST
WINDS WILL CONTINUE OVER THE HIGHER EXPOSED TERRAIN. THE STRONGEST
WINDS LOOK TO BE THIS AFTERNOON.
OTHER AREAS WILL SEE MOSTLY MID TO HIGH CLOUDS...BUT AT TIMES
CLOUDS WILL THICKEN WITH A CHANCE OF PRECIPITATION IN THE HIGHER
NORTH AND CENTRAL VALLEYS. THE WARMING TREND WILL CONTINUE...SO
PRECIPITATION MAY FALL AS RAIN OR MIXED RAIN AND SNOW IN THESE
HIGHER VALLEYS...ESPECIALLY DURING THE AFTERNOON. HOWEVER SINCE
THE MAIN FORCING MECHANISM IS OROGRAPHICS...DO NOT EXPECT MUCH
VALLEY PRECIPITATION. ALSO TEMPERATURES HAVE BEEN VERY WARM
TONIGHT MOST AREAS...SO OVERRUNNING PRECIPITATION IS NOT EXPECTED
IN VALLEY LOCATIONS. THE SAN JUANS MAY ALSO SEE SOME LIGHT
SNOW...BUT IT WILL BE MUCH MORE SPOTTY THERE.
.LONG TERM...(FRIDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 420 AM MST THU FEB 13 2014
SNOW BEGINS AGAIN OVER THE NORTHERN AND CENTRAL MOUNTAINS FRIDAY
NIGHT AS DEEP PACIFIC MOVES THROUGH A RIDGE TO THE WEST...THEN
CONTINUES INTO SATURDAY EVENING. LIFT PRIMARILY OROGRAPHIC DURING
THIS PERIOD...THOUGH A COUPLE OF LOW-AMPLITUDE WAVES WILL BRING
PERIODS OF ENHANCED SNOWFALL. MODELS STRUGGLE WITH TIMING OF THESE
WEAK FAST MOVING FEATURES EVEN IN THE EARLY PERIODS OF THE
FORECAST SO WILL NOT ATTEMPT TO PIN DOWN A SPECIFIC PERIOD FOR
THEIR PASSAGE. WAA WILL HINDER ACCUMULATIONS THOUGH NAM SUGGESTS
ADVISORY LEVEL SNOW POSSIBLE FOR ZONES 4 AND 13 DURING THIS
PERIOD.
FLAT RIDGE SHIFTS OVER THE AREA SATURDAY NIGHT AND SUNDAY FOR A
PERIOD OF QUIET CONDITIONS. HOWEVER...BOTH EC AND GFS WERE IN GOOD
AGREEMENT WITH A WEAK SHORTWAVE TROUGH SWEEPING EASTWARD ACROSS
THE FORECAST AREA SUNDAY AFTERNOON THROUGH SUNDAY NIGHT. SNOWFALL
EXPECTED TO AGAIN FAVOR THE NORTHERN AND CENTRAL MOUNTAINS WITH
ONLY LIGHT ACCUMULATIONS INDICATED IN MODEL GUIDANCE.
DRY ZONAL FLOW SETS UP FOR MONDAY AND TUESDAY. MODELS SUGGEST
ANOTHER SHORTWAVE TROUGH IMPACTING THE REGION TUESDAY NIGHT INTO
WEDNESDAY. HOWEVER...EC AND GFS OUT OF PHASE BY THIS TIME WITH GFS
SHALLOWER AND FASTER THAN THE EC. CONSEQUENTLY...WILL LEAVE
BLENDED FORECAST ALONE UNTIL MODEL CONSISTENCY IMPROVES.
TEMPERATURES WILL BE MILD ACROSS THE REGION INTO THE EARLY PART OF
THE WEEKEND BEFORE THE NEXT SYSTEM USHERS COOLER AIR INTO THE
NORTH SUNDAY AFTERNOON WITH COOLER AIR SPREADING SOUTHWARD SUNDAY
NIGHT. AS A RESULT...THE EARLY PART OF THE COMING WEEK LOOKS TO
RUN 5 TO 10 DEGREES COOLER WHICH IS A BIT CLOSER TO SEASONAL
NORMS.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z FRIDAY MORNING)
ISSUED AT 1000 AM MST THU FEB 13 2014
MOIST WESTERLY FLOW WILL CONTINUE TO BRING WIDESPREAD SNOWFALL TO
THE NORTHERN AND CENTRAL MOUNTAINS THROUGH FRIDAY. MOUNTAINS WILL
BE FREQUENTLY OBSCURED EAST OF A LINE FROM KCAG SOUTH TO KTEX.
PRECIPITATION IS LIKELY TO BRING BRIEF MVFR CONDITIONS TO
KHDN...KSBS...KEGE...AND KASE IN SN OR SN/RA THIS AFTERNOON. BRIEF
IFR CONDITIONS ARE POSSIBLE OVERNIGHT. ELSEWHERE...VFR CONDITIONS
WILL CONTINUE. FRIDAY MTN OBSCURATIONS AND SHOWERS WILL DIMINISH
SOMEWHAT BUT PERIODS OF BRIEF MVFR ARE EXPECTED TO CONTINUE FOR
FOUR FAVORED TAF SITES LISTED ABOVE.
&&
.GJT WATCHES/WARNINGS/ADVISORIES...
CO...WINTER STORM WARNING UNTIL MIDNIGHT MST TONIGHT COZ004-013.
WINTER WEATHER ADVISORY UNTIL MIDNIGHT MST TONIGHT COZ010.
UT...NONE.
&&
$$
UPDATE...JOE
SHORT TERM...EH
LONG TERM...NL
AVIATION...JOE
AREA FORECAST DISCUSSION
NWS ALBANY NY
433 PM EST THU FEB 13 2014
.SYNOPSIS...
A NOR`EASTER WILL MOVE NORTHEAST OF LONG ISLAND TONIGHT AND INTO
THE GULF OF MAINE BY TOMORROW MORNING. THIS POWERFUL STORM WILL
BRING A SIGNIFICANT SNOWFALL TO EASTERN NEW YORK AND WESTERN NEW
ENGLAND. THE SNOW WILL TAPER TO SCATTERED SNOW SHOWERS AND
FLURRIES BY LATE MORNING...BUT BRISK CONDITIONS AND SEASONABLE
TEMPERATURES WILL PERSIST INTO THE AFTERNOON. ANOTHER DISTURBANCE
WILL BRING MAINLY LIGHT SNOW TO THE REGION TO OPEN THE WEEKEND.
&&
.NEAR TERM /UNTIL 6 AM FRIDAY MORNING/...
...THE ENTIRE FORECAST AREA HAS BEEN UPGRADED TO WINTER STORM
WARNINGS...
AS OF 433 PM EST...HERKIMER AND HAMILTON COUNTIES HAVE BEEN
UPGRADED TO THE WINTER STORM WARNINGS THAT WILL BE IN EFFECT UNTIL
NOONTIME TOMORROW.
WINTER STORM WARNINGS CONTINUE UNTIL 10 AM EST FRIDAY FOR ALL OF
WESTERN NEW ENGLAND...THE MOHAWK VALLEY...GREATER CAPITAL
REGION...EASTERN CATSKILLS...HELDERBERGS...MID HUDSON VALLEY...
TACONICS...LAKE GEORGE SARATOGA REGION...
AN IMPRESSIVE MESOSCALE SNOWBAND CONTINUES TO LIFT NORTH TO
NORTHEAST ACROSS THE NRN CAPITAL REGION...MOHAWK VALLEY...NRN
TACONICS...SARATOGA AND SRN VT IN THE MID TO LATE AFTERNOON. SOME
SNOWFALL RATES OF 2 INCHES AN HOUR WERE REPORTED WITH LARGE
AGGREGATING SNOWFLAKES UP TO SILVER DOLLAR SIZE AT THE NWS AT
ALBANY OFFICE BTWN 200 PM AND 300 PM.
THE NOR`EASTER IS JUST EAST OF SRN NJ AT 2000 UTC AND IS 989 HPA
BASED ON THE RUC AND ANALYSIS...AND THE BEST PRESSURE FALLS ON THE
ORDER OF 8-10+ HPA/3 HRS ARE NOW OVER CT/RI/ERN MA. THE LATEST
GFS/NAM/ECMWF GUIDANCE HAS THE IMPRESSIVE CYCLONE TRACKING A
LITTLE BIT CLOSER TO THE COAST. THIS SHIFT HAVING THE CYCLONE MOVE
OVER RI AND ERN MA WILL ALLOW THE HEAVY SNOWBAND ON THE NW SIDE
OF THE SYSTEM IMPACT THE ENTIRE FORECAST AREA...AS FAR WEST AS
THE WRN MOHAWK VALLEY AND THE SRN DACKS NOW.
THE WATER VAPOR LOOP THIS AFTERNOON SHOWS AN DISTINCT DRY SLOT
MOVING ALONG EAST COAST INTO NJ AND PARTS OF WRN NEW ENGLAND. THIS
WILL ALLOW THE PCPN TO LIGHTEN IN INTENSITY WITH SOME SLEET AND
FREEZING RAIN POSSIBLE OVER THE MID HUDSON VALLEY...SRN TACONICS
...SRN-CNTRL BERKS AND NW CT. THE MID LEVEL DRYING IS EXPECTED TO
RESULT IN A POSSIBLE LOSS OF ICE NUCLEI IN THE CLOUDS...RESULTING IN THE
MIXED PRECIP ACROSS THESE AREAS FOR A SHORT-PERIOD OF TIME.
HOWEVER...THE H500 CLOSED UPPER LEVEL LOW CENTERED OVER NC/VA IS
BECOMING NEGATIVELY TILTED EMBEDDED IN THE LONG WAVE TROUGH. THIS
CLOSED LOW WILL CAPTURE THE SFC CYCLONE...AND ALLOW VERY HEAVY
SNOWFALL TO RETURN TONIGHT. OUR CONFIDENCE IS VERY HIGH FOR A
NORTH TO SOUTH OR SLIGHTLY N/NW TO S/SE ORIENTED MESOSCALE
SNOWBAND TO HIT MOST OF ERN NY AND WRN NEW ENGLAND.
BASED ON CSTAR RESEARCH WITH SUNYA THESE MESOSCALE SNOWBANDS ARE
VERY LIKELY WITH THE H700 CLOSED CIRCULATION MOVING FROM ERN
PA/NJ/DELMARVA REGION TO ERN NY AND WRN NEW ENGLAND BY 06Z/FRI.
ON THE NW SIDE OF THE CLOSED LOW IS WHERE A SIGNIFICANT PIVOTING
MESOSCALE SNOWBAND IS LIKELY TO SET UP. ALSO...THE LEFT FRONT QUAD
OR LEFT EXIT REGION REGION OF 130-140+ KT JET STREAK WILL BE
MOVING ACROSS WRN NEW ENGLAND WITH STRONG OMEGA/UPWARD VERTICAL
MOTION OVER A LARGE PORTION OF THE REGION.
A QUICK CHECK OF CROSS-SECTIONS DOWN THE HUDSON RIVER VALLEY FROM THE
NAM AND GFS TONIGHT SHOW STRONG UPWARD VERTICAL VELOCITIES WITH
STEEPLY SLOPED FGEN BENEATH NEGATIVE EPV /AT 400-500 HPA/ BTWN 00Z-
06Z WITHIN THE DEFORMATION ZONE TO THE SYSTEM...AND THE OPTIMAL DENDRITIC
GROWTH ZONE /-10C TO -16C/ INTERSECTS THIS AREA OF STRONG FGEN AND OMEGA
DURING THIS TIME FRAME. SOME HOURLY SNOWFALL RATES OF 1 TO 3
INCHES LOOK LIKELY. THE STRONG MESOSCALE BANDING IN ASSOCIATION
WITH THE MID AND UPPER LEVEL LOW MAY ALSO ALLOW FOR A FEW RUMBLES
OF THUNDER IN THE HEAVIER SNOW /THUNDER SNOW !/. SOME CG LTG
STRIKES CONTINUE OVER THE CHESAPEAKE BAY REGION LATE THIS
AFTERNOON.
THE GFS/NAM/ECMWF SHOWS A LARGE AMOUNT OF ATLANTIC MOISTURE BEING
UTILIZED FOR THE NIGHT TIME PERIOD. PWAT ANOMALIES ARE 1 TO 2 STANDARD
DEVIATIONS ABOVE NORMAL. TONIGHT...ADDITIONAL SNOWFALL AMOUNTS OF 6
TO 12 INCHES WILL BE LIKELY WITH LOCALLY HIGHER AMOUNTS...ON TOP OF WHAT
HAS ALREADY FALLEN.
OVERALL...THE TOTAL SNOWFALL ACCUMULATIONS HAVE BEEN INCREASED
WITH 14 TO 18 INCHES FROM THE CAPITAL REGION...SOUTHERN
VERMONT...AND THE NRN CATSKILLS SOUTH AND EAST EXCEPT FOR SRN
LITCHFIELD AND ERN WINDHAM CTY WHERE 10-14 INCHES IS LIKELY. THE
MIXED PCPN MAY KEEP THE SNOW AMOUNTS LOWER IN PARTS OF NW CT. SNOW
TOTALS OF 18-24" FOR THE SRN GREENS...PART OF THE BERKSHIRES...AND
THE ERN CATSKILLS.
THE WRN-CNTRL MOHAWK VALLEY...LAKE GEORGE SARATOGA REGION...AND
THE SRN DACKS ARE EXPECTED TO HAVE 8 TO 14 INCHES.
BLOWING AND DRIFTING SNOW WILL BE A PROBLEM OVERNIGHT AS THE LOW
DEEPENS AND INTENSIFIES TO AROUND 975 HPA IN THE GULF OF MAINE. N
TO NW WINDS OF 10 TO 20 MPH WITH SOME GUSTS TO 30 TO 35 MPH WILL
BE COMMON. SOME OF THE GUSTS MAY NOT MIX TO THE SFC TONIGHT DUE
TO A STRONG LOW-LEVEL INVERSION...AND THE HEAVY PCPN.
SNOW TO LIQUID RATIOS OF 10-13:1 HAVE BEEN USED FOR THE ENTIRE
EVENT FOR MOST OF THE AREA. THE WETTER SNOW WILL LIKELY BE IN THE
SOUTHEAST EXTREME OF THE FCST AREA WHERE THE PCPN WILL MIX FOR A
BRIEF PERIOD. SNOW TO LIQUID RATIOS OF 6-8:1 WERE USED EARLY
TONIGHT TO ACCOUNT FOR SLEET AND FREEZING RAIN. IT SHOULD BE NOTED
ANY ICE ACCUMULATION SHOULD BE VERY LIGHT FOR THE MID HUDSON
VALLEY/SRN BERKS/SRN TACONICS/NW CT WITH A COATING TO A TENTH OF
AN INCH.
&&
.SHORT TERM /6 AM FRIDAY MORNING THROUGH SATURDAY NIGHT/...
TOMORROW...THE NOR`EASTER MOVES NORTHEAST OF THE GULF OF MAINE
TOWARDS NOVA SCOTIA BY THE EARLY PM WITH DEFORMATION SNOW AND SNOW
SHOWERS DIMINISHING BY NOONTIME. THE WARNING GOES FOR HERKIMER AND
HAMILTON COUNTIES...AS MOISTURE DOWNWIND OF LAKE ONTARIO MAY BE
UTILIZED. ADDITIONAL SNOWFALL AMOUNTS WILL RANGE FROM A HALF AN
INCH TO AN INCH. SOME WESTERLY UPSLOPE SNOW SHOWERS WILL LINGER
ALONG THE SPINE OF THE SRN GREEN MTNS. WEAK UPPER LEVEL RIDGING
BUILDS IN FOR THE AFTERNOON...AND H850 TEMPS WILL ACTUALLY BE NEAR
NORMAL IN THE -6C TO -8C RANGE. MAX TEMPS WILL BE NEAR NORMAL WITH
POSSIBLY A FEW BREAKS OF SUN IN THE AFTERNOON. HIGHS WILL
GENERALLY BE IN THE LOWER TO M30S ACROSS MOST OF THE
REGION...POSSIBLY SOME U30S IN THE MID HUDSON VALLEY...AND MID AND
UPPER 20S OVER THE MTNS.
FRIDAY NIGHT...ANOTHER SRN STREAM SYSTEM MOVES TOWARDS THE MID
ATLANTIC REGION...WITH A NRN STREAM UPPER LEVEL TROUGH APPROACHING
FROM THE GREAT LAKES REGION AND SE ONTARIO. IT APPEARS THESE
SHORT-WAVES WILL NOT PHASE TOGETHER UNTIL NEAR THE DELMARVA
REGION...AS THE LONGWAVE TROUGH TURNS NEGATIVE. SOME LIGHT SNOW
MAY SPREAD INTO THE REGION TOWARDS DAYBREAK. SOME CHC POPS HAVE
BEEN ADDED TO FORECAST. LOWS WILL GENERALLY BE IN THE TEENS AND L20S.
SATURDAY-SATURDAY NIGHT...THE SUBSEQUENT COASTAL WAVE BASED ON THE
GFS/ECMWF/NAM APPEARS IT WILL DEVELOP FAR ENOUGH SOUTH THAT IT
WILL HAVE A MINIMAL IMPACT ON THE REGION. LIGHT SNOW CAN NOT BE
RULED OUT...AND HIGH CHC AND LIKELY POPS WERE ADDED TO THE FCST
AREA FOR SATURDAY. SNOW ACCUMS OF 1 TO 3 INCHES MAY BE POSSIBLE.
THE COASTAL WAVE PASSES WELL EAST OF CAPE COD SATURDAY NIGHT AND
TOWARDS NOVA SCOTIA. SOME LAKE EFFECT AND WESTERLY UPSLOPE SNOW
SHOWERS WILL LINGER AGAIN. AFTER MAX TEMPS IN THE M20S TO L30S...LOWS
WILL FALL BACK INTO THE SINGLE DIGITS AND TEENS /EXCEPT SOME BELOW
ZERO READINGS OVER THE SRN DACKS/...AS A STRONGER SURGE OF COLD
ADVECTION MOVES INTO THE REGION.
&&
.LONG TERM /SUNDAY THROUGH THURSDAY/...
THE DEEPENING LOW OVER THE CANADIAN MARITIMES WILL BE FAR ENOUGH
AWAY THAT IT WILL HAVE LITTLE IF ANY IMPACT ON THE FORECAST AREA ON
SUNDAY...BUT A WEAK UPPER LEVEL SYSTEM MAY PRODUCE SOME ISOLATED TO
SCT SNOW SNOW SHOWERS ACROSS AREAS WEST OF THE HUDSON VALLEY ON
SUNDAY. OTHERWISE...HIGH PRESSURE BUILDS IN SUNDAY NIGHT AND MONDAY
WITH FAIR AND DRY BUT VERY COLD WEATHER. HIGHS SUNDAY WILL BE IN THE
MID 20S TO MID 30S. LOWS AROUND ZERO TO AROUND 12 BELOW ZERO SUNDAY
NIGHT. SURFACE WINDS MAY CONTINUE STRONG ENOUGH THROUGH SUNDAY NIGHT
AND EARLY MONDAY MORNING FOR WIND CHILL READINGS TO REACH ADVISORY
LEVELS IN SOME AREAS. HIGHS MONDAY WILL GENERALLY BE IN THE 20S.
A FAST MOVING BUT RELATIVELY MOIST CLIPPER SYSTEM WILL MOVE ACROSS
NY STATE MONDAY NIGHT. HAVE FORECAST LIKELY POPS IN ALL AREAS EXCEPT
THE EXTREME SOUTHERN PART OF THE FORECAST AREA. DESPITE THE SYSTEM
PASSING THROUGH TO THE NORTH OF THE REGION WITH A STRONG SOUTHERLY
FLOW AHEAD OF IT...MODELS GENERALLY SUPPORT SNOW AS THE PCPN TYPE.
LOWS MONDAY NIGHT WILL BE 10 TO 20. THE SYSTEM QUICKLY MOVES OUT
TUESDAY MORNING...BUT CYCLONIC FLOW AROUND IT MAY KEEP SCATTERED
RAIN/SNOW SHOWERS ACROSS THE REGION INTO TUESDAY AFTERNOON. HIGHS
TUESDAY WILL BE IN THE 30S TO LOWER 40S AS THE AIR BEHIND THIS
SYSTEM WILL BE OF PACIFIC ORIGIN.
THE RELATIVELY MILD PACIFIC AIR WILL PERSIST THROUGH THURSDAY WITH
NOTHING MORE THAN A 30 TO 40 PERCENT CHANCE OF MOSTLY RAIN SHOWERS
THURSDAY AS ANOTHER WEAK LOW PRESSURE SYSTEM PASSES BY TO OUR NORTH.
LOWS TUESDAY NIGHT WILL BE IN THE UPPER TEENS TO MID 20S. HIGHS
WEDNESDAY IN THE MID 30S TO LOWER 40S. LOWS WEDNESDAY NIGHT IN THE
20S. HIGHS THURSDAY IN THE UPPER 30S TO MID 40S.
&&
.AVIATION /20Z THURSDAY THROUGH TUESDAY/...
SNOW CONTINUES TO FALL ACROSS THE TERMINALS DUE TO A STRENGTHENING
NOR`EASTER THAT WILL IMPACT THE REGION THROUGH TONIGHT AND INTO
FRIDAY MORNING.
SNOW INTENSITY WILL GENERALLY BE MODERATE TO OCCASIONALLY HEAVY THIS
AFTERNOON...ESPECIALLY FROM KPSF-KPOU. THIS EVENING THERE IS
EXPECTED TO BE AN ADDITIONAL SURGE OF HEAVY SNOWFALL AS THE
NOR`EASTER MOVES NORTHWARD INTO SOUTHERN NEW ENGLAND. FLYING
CONDITIONS ARE EXPECTED TO BE SOLIDLY LIFR/IFR THROUGH THE REST OF
THE AFTERNOON AND MUCH OF THE NIGHT. OCCASIONAL VLIFR VSBYS IN HEAVY
SNOW ARE EXPECTED THIS EVENING ESPECIALLY FROM KALB-KPSF-KPOU AND
POSSIBLY EVEN KGFL. CONDITIONS WILL IMPROVE FROM SOUTH TO NORTH AS
THE STORM PULLS AWAY FROM AROUND 10Z-13Z FRIDAY. VFR CONDITIONS WILL
RETURN BY MID TO LATE FRIDAY MORNING.
NORTHERLY WINDS WILL STRENGTHEN THIS AFTERNOON AND EVENING TO AROUND
10-15 KT WITH GUSTS OF 20-25 KT. WINDS WILL SHIFT TO THE NORTHWEST
TOWARDS DAYBREAK FRIDAY...WITH SPEEDS INCREASING TO 15-20 KT WITH
GUSTS TO 30 KT AT KALB/KPSF FRIDAY MORNING.
OUTLOOK...
FRIDAY NIGHT: MODERATE OPERATIONAL IMPACT. CHANCE OF SN.
SATURDAY: HIGH OPERATIONAL IMPACT.BREEZY LIKELY SN.
SATURDAY NIGHT: LOW OPERATIONAL IMPACT.BREEZY NO SIG WX.
SUNDAY: NO OPERATIONAL IMPACT. NO SIG WX.
SUNDAY NIGHT: NO OPERATIONAL IMPACT. NO SIG WX.
WASHINGTONS BIRTHDAY: NO OPERATIONAL IMPACT. NO SIG WX.
MONDAY NIGHT: MODERATE OPERATIONAL IMPACT. LIKELY SN.
TUESDAY: MODERATE OPERATIONAL IMPACT. CHANCE OF RA...SN.
&&
.HYDROLOGY...
NO HYDRO PROBLEMS ARE ANTICIPATED THROUGH THE NEXT FIVE DAYS.
A WIDESPREAD HEAVY SNOWFALL WILL IMPACT THE HYDRO SERVICE AREA
INTO FRIDAY MORNING. SNOWFALL AMOUNTS ARE EXPECTED TO BE HEAVY
ACROSS THE REGION...WITH THE HEAVIEST SNOW FROM THE CAPITAL
DISTRICT...SRN VT...AND NRN CATSKILLS SOUTH AND EAST.
TOTAL LIQUID EQUIVALENT FROM THE STORM SYSTEM WILL RANGE FROM A
WIDESPREAD INCH TO INCH AND AN HALF OVER THE HSA...EXCEPT HALF AN
INCH TO AN INCH OVER THE WRN DACKS AND WRN MOHAWK VALLEY.
ANOTHER DISTURBANCE WILL BRING SOME LIGHT SNOWFALL TO PARTS OF THE
REGION ON SATURDAY WITH LIGHT LAKE EFFECT SNOW SHOWERS SATURDAY
NIGHT INTO SUNDAY.
THE NEXT CHANCE FOR SIGNIFICANT PRECIPITATION LOOKS TO BE MONDAY
NIGHT INTO TUESDAY. THIS LOOKS TO BE INTIALLY A SNOW...POSSIBLY
CHANGING TO A WINTRY MIX EVENT.
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 STORM WARNING UNTIL 10 AM EST FRIDAY FOR CTZ001-013.
NY...WINTER STORM WARNING UNTIL 10 AM EST FRIDAY FOR NYZ039>043-
047>054-058>061-063>066-082>084.
WINTER STORM WARNING UNTIL NOON EST FRIDAY FOR NYZ032-033-038.
MA...WINTER STORM WARNING UNTIL 10 AM EST FRIDAY FOR MAZ001-025.
VT...WINTER STORM WARNING UNTIL 10 AM EST FRIDAY FOR VTZ013>015.
&&
$$
SYNOPSIS...WASULA
NEAR TERM...WASULA
SHORT TERM...WASULA
LONG TERM...GJM
AVIATION...JPV
HYDROLOGY...HWJIV/WASULA
AREA FORECAST DISCUSSION
NWS TAUNTON MA
1256 AM EST THU FEB 13 2014
.SYNOPSIS...
HIGH PRESSURE MOVES OFFSHORE TONIGHT. A SIGNIFICANT WINTER STORM
WILL IMPACT THE REGION THURSDAY INTO FRIDAY MORNING. AN OFFSHORE
STORM IS EXPECTED FRIDAY NIGHT INTO SATURDAY. DRY FRIGID WEATHER
PREVAILS FOR THE REMAINDER OF THE WEEKEND...WHILE ANOTHER STORM-
SYSTEM IS POISED FOR THE EARLY- TO MID-WEEK PERIOD.
&&
.NEAR TERM /UNTIL 6 AM THIS MORNING/...
1245 AM UPDATE...
LIGHT SNOW ENCROACHING ON NYC AND BASED ON THE HRRR IT STILL
APPEARS SNOW WILL BEGIN ACROSS PORTIONS OF N CT TO THE S COAST
AROUND 09Z REACHING THE MASS PIKE AROUND 12Z. COULD SEE UP TO AN
INCH ACCUM BY 7 AM NEAR THE SOUTH COAST AND PORTIONS OF N CT.
BAND OF HEAVY SNOW ASSOCD WITH MID LEVEL FRONTOGENESIS WILL BE
APPROACHING THE S COAST AROUND 12Z.
&&
.SHORT TERM /6 AM THIS MORNING THROUGH 6 PM FRIDAY/...
7 AM UPDATE...
CONSIDERING AN ANOMALOUS LOW PRES CENTER 3-4 STANDARD DEVIATIONS
FEEL THAT WIND AND WIND GUSTS ARE NOT APPROPRIATELY MODELED.
CONSIDERING 40-50 KT E/NE FLOW ROUGHLY 1500 FT AGL AND CONSULTING
WIND ADV / HIGH WIND WARNING CLIMATOLOGY...FEEL THAT DESPITE THE
STOUT INVERSION AT THE SURFACE...THAT PRECIP DRAG PROCESSES AND
SUCH A TIGHT PRES GRADIENT SHOULD YIELD AT LEAST WIND ADV CRITERIA
/31-39 MPH SUSTAINED WINDS WITH 46-57 MPH GUSTS/ FOR ALL SHORELINE
COMMUNITIES. WHETHER THIS NEEDS TO BE UPGRADED AND/OR EXPANDED IN
AREA I WILL LEAVE FOR THE MIDNIGHT SHIFT TO CONSIDER.
OTHERWISE I LEAVE THIS FOR THINKING FOR THE MIDNIGHT SHIFT AND ALL
OTHERS READING THIS DISCUSSION...
HIGHER DEWPOINT AIR WRAPPING INTO THE LOW ITSELF OVER COLDER
OCEAN AND SNOW PACK IS LIKELY TO YIELD AREAS OF DENSE FOG.
EXPECTING VISIBILITIES DOWN TO A HALF-MILE DESPITE THE STRONG AND
GUSTY WINDS. EXPECTING A SOUP AS AN ABUNDANCE OF WARM-MOISTURE
WILL STREAM ACROSS THE REGION. HAVE APPENDED THE WEATHER GRIDS
ACCORDINGLY FOR AREAS THAT WILL SEE THE CHANGEOVER TO RAIN.
IN ADDITION FOR AREAS WHICH WILL SEE A CHANGEOVER TO RAIN...
ANOMALOUS PWATS AND THE EXPECTATION OF 1.0-1.5 INCHES OF PRECIP
MAINLY FOR THE S/SE COASTAL PLAINS LEADS TO SOME CONCERN OF
NUISANCE FLOODING WITH DRAINS CLOGGED WITH SNOW...AS WELL AS
POTENTIAL ROOF COLLAPSES AS THE WEIGHT OF WATER AND SNOW WILL BE
AN ISSUE. AREAS IMPACTING STILL HAVE SNOWPACKS AROUND 6-INCHES AT
PRESENT. DURING THE STORM TRANSITION AROUND MIDDAY THURSDAY INTO
THURSDAY NIGHT...SHORT-TERM FLOOD HEADLINES MAY BE WARRANTED.
AS A FINAL NOTE...LOOK AT CIPS ANALOGS AND EVALUATE THOSE WHICH
ARE ALSO ENSO-NEUTRAL. WHILE THERE IS SOME CONTINUED UNCERTAINTY
ON THE EXACT OUTCOMES OF THE STORM...THE OVERALL MEAN OF THREATS
GIVE SOME IDEA OF WHAT OUTCOMES THE NE CONUS SHOULD PREPARE FOR
AND ANTICIPATE.
PREVIOUS DISCUSSION...
LOW PRESSURE MOVES UP THE COAST SPREADING DEEP LIFT AND MOISTURE
ACROSS ALL OF SOUTHERN NEW ENGLAND. OUR AREA WILL BE UNDER THE
RIGHT ENTRANCE REGION OF THE UPPER JET...WHILE LOW AND MID LEVEL
FRONTOGENETIC FORCING WILL BE FAVORABLE OVER MOST OF THE REGION.
TEMPERATURE PROFILES FAVOR SNOW IN ALL AREAS INITIALLY...BUT WITH
ABOVE-FREEZING AIR MOVING UP FROM THE SOUTH DURING THE MORNING AND
CHANGING THE SNOW TO RAIN IN THE COASTAL PLAIN BY MIDDAY OR EARLY
AFTERNOON. THE WARMER AIR MAY SPREAD INTO NORTHEAST CT AND
PARTS OF CENTRAL MASS...BUT LESS CONFIDENCE ON THIS DUE TO THE
SNOWCOVER AND ITS COOLING INFLUENCE NEAR THE SURFACE. THE WARM
TEMPS ALOFT AND COOLER TEMPS NEAR THE SURFACE MAY RESULT IN A
PERIOD OF FREEZING RAIN DURING THE AFTERNOON AND EVENING. WESTERN
AREAS SHOULD REMAIN MAINLY AS SNOW. WITH STRONG LIFT IN THE SNOW
GROWTH ZONE...PERIODS OF INCH/HOUR SNOWFALL RATES ARE LIKELY JUST
NORTH/WEST OF THE CHANGEOVER LINE.
MODELS SIGNAL A WELL DEFINED COMMA HEAD MOVING ACROSS SOUTHERN NEW
ENGLAND DURING THURSDAY NIGHT. THIS TAKES PLACE JUST AS THE
SURFACE LOW PASSES...OVER OR NEAR CAPE COD...AND WINDS SHIFT TO
NORTH/NORTHWEST DRAWING COLD AIR BACK ACROSS ALL OF OUR AREA. THIS
WILL GENERATE FRONTOGENTIC FORCING AND LIFT AS ANY RAIN OR ICE
CHANGES BACK TO SNOW. WESTERN AND CENTRAL MASS AND SOUTHERN NH ARE
MOST AT RISK FOR HEAVIEST ACCUMULATIONS.
EXPECTED SNOWFALL RANGES FROM 14-18 INCHES IN THE EAST SLOPES OF
THE BERKSHIRES AND THE WORCESTER-MONADNOCK HILLS TO 1-2 INCHES ON
THE CAPE AND ISLANDS. COULD BE A FEW SPOTS IN THE BERKSHIRE ZONES
THAT HAVE 18-24 INCHES. WE ARE EXPECTING A SHARP GRADIENT OF
SNOW ACCUMULATION JUST INLAND OF THE I-95 CORRIDOR. ICE
ACCUMULATIONS OF UP TO 0.25 INCHES ARE POSSIBLE OVER PARTS OF
NORTHERN CT AND CENTRAL MASS.
THE LOW LEVEL JET PULLED NORTH BY THE STORM WILL MOVE ACROSS
EASTERN MASS/RI THURSDAY AFTERNOON AND EARLY NIGHT. THE MOST
FAVORABLE LAPSE RATES WILL REMAIN OFFSHORE OF CAPE COD. BUT LAPSE
RATES APPROACHING MOIST ADIABATIC ARE POSSIBLE...WHICH WOULD ALLOW
THE 50 MPH WINDS TO MIX TO THE SURFACE IN RAIN. THE GREATEST RISK
WILL BE ON THE CAPE AND ISLANDS...AND ACROSS CAPE ANN IN NORTHEAST
MASS. A WIND ADVISORY HAS BEEN ISSUED FOR THESE AREAS.
&&
.LONG TERM /FRIDAY NIGHT THROUGH WEDNESDAY/...
*/ HIGHLIGHTS...
- LINGERING LIGHT SNOW AND WINDY CONDITIONS FOR FRIDAY
- LIGHT SNOW POTENTIAL WITH OFFSHORE STORM FRIDAY NIGHT-SATURDAY
- INITIALLY WINDY...COLD/DRY CONDITIONS PREVAIL FOR THE WEEKEND
- ANOTHER STORM SYSTEM EXPECTED AROUND EARLY- TO MID-WEEK
- A WARMING TREND TOWARDS LATE FEBRUARY?
*/ OVERVIEW AND MODEL PREFERENCE...
CONTINUED TROUGHING AMPLIFIED BY INDIVIDUAL DISTURBANCES WILL RESULT
IN ANOTHER STORM SYSTEM AROUND SATURDAY FOLLOWED BY AN ARCTIC SURGE
BY THE BEGINNING OF NEXT WEEK. THOUGH VARIABILITY WITHIN MODEL
OUTPUT CONCERNING THE SATURDAY STORM...SOME IMPACT IS EXPECTED.
A NON-ECMWF CONSENSUS BLEND OF SOLUTIONS IS PREFERRED OVER THE
WEEKEND. FEEL THE SURGE OF COLDER AIR ACROSS A DEEP SNOW PACK LEFT
BEHIND BY THE THURSDAY STORM SHOULD SHUNT THE BETTER BAROCLINIC
ZONE SOUTH AND EAST. IN ADDITION THE BETTER DEEP-LAYER ASCENT AND
DYNAMICS ARE EAST AND CLOSER TO NOVA SCOTIA. THEREFORE HAVE
GREATER CONFIDENCE TOWARDS A REGENERATIVE AREA OF LOW PRES WELL-
OFFSHORE OF THE REGION FRIDAY NIGHT INTO SATURDAY.
THERE IS SOME HOPE OF A PATTERN SHIFT PER ENSEMBLE MEMBERS TOWARDS
LATE FEBRUARY AS +AO/+NAO TREND IS PREFERRED INDICATING A LOCK-UP OF
COLDER AIR ACROSS THE POLES AND A PROGRESSIVE STORM PATTERN. DAY-8
CANADIAN COMPOSITE SHOWS POSITIVE HEIGHT ANOMALIES OVER THE NE CONUS
WITH ENHANCED RIDGING ACROSS THE EASTERN PACIFIC. WHETHER THIS COMES
TO FRUITION WE WILL HAVE TO WAIT AND SEE.
FOR NEXT WEEK...A CONSENSUS BLEND IS PREFERRED BUT CAUTION IS
EXERCISED BY THE FACT THAT DETERMINISTIC AND ENSEMBLE MEANS EXHIBIT
TIMING INCONSISTENCIES WITH AN ANTICIPATED EARLY- TO MID-WEEK
DISTURBANCE. PER ENSEMBLE TRENDS OUTLINED ABOVE...A WARMER TREND
INTO THE LATE-WEEK IS PREFERRED.
*/ DAY-TO-DAY DETAILS...
FRIDAY...
DEPARTING STORM BECOMING STACKED AS IT UNDERGOES OCCLUSION CUTTING
OFF FROM BETTER MOISTURE /DYING-PHASE/. DRIER AIR WRAPS IN AND ANY
AND ALL PRECIP SHOULD CONCLUDE THROUGH THE DAY. ANTICIPATING SNOW TO
LINGER N/W WITHIN THE COMMA-HEAD OF THE DEPARTING STORM. FOCUS OF
SNOW WITH W/NW FLOW LIKELY ALONG W-SLOPES OF HIGHER TERRAIN WHERE
SOME MID-LEVEL FORCING LINGERS ALBEIT QUICKLY DIMINISHING.
MAIN CONCERN IS WINDS. DEEP CENTRAL PRESSURE OFFSHORE...STRONG
ISALLOBARIC RESPONSE...GUSTY WEST WINDS AROUND 40 MPH 2 KFT AGL.
WHETHER WIND HEADLINES WILL NEED TO BE CONSIDERED REMAINS TO BE
SEEN. GREATEST THREAT WILL BE N/E /ESP CAPE ANN AND EASTERN CAPE/.
STEEP LAPSE RATES UP TO H9 SHOULD EASILY ALLOW MOMENTUM TRANSFER
TO THE SURFACE.
AT LEAST GALES OVER THE WATERS. WITH RECENT SNOWS...FEEL IT WILL BE
COLDER THAN GUIDANCE SUGGESTS /ESP NORTH AND WEST/. HAVE LOWERED
TEMPS /ESP OVERNIGHT/ BY A FEW DEGREES.
FRIDAY NIGHT INTO SATURDAY...
SECOND SET OF PACIFIC WAVES AMPLIFIES THE TROUGH REGIME ACROSS THE
NE CONUS INVOKING AN AREA OF LOW PRES OFFSHORE OF SNE. SOME QUESTION
AS TO ITS PROXIMITY. PER GFS/UKMET...ITS DEVELOPMENT APPEARS TO
REMAIN WELL S/E OUTSIDE THE 40N/70W BENCHMARK RESULTING IN MINIMAL
IMPACT. BROADSCALE MODEL AGREEMENT /EVEN THE ECMWF/ KEEPING THE BEST
ASCENT AND DYNAMICS EAST. WITH RECENT SNOWS AND EXPECTATION OF
COLDER CONDITION OVER SNE...REGION OF BETTER BAROCLINICITY SHOULD
ALSO REMAIN WELL-OFFSHORE WITH N/NW WINDS OVER THE WATERS FROM THE
INTERIOR.
N/NW WINDS REARWARD MAY CHURN UP SOME OCEAN-EFFECT PROCESSES...BUT
SOME UNCERTAINTY AS TO LOW-LEVEL MOISTURE AVAILABILITY AND UNIFORM
WIND PROFILE. SHOULD SEE STEEP LAPSE RATES UP TO H8 AND A DECENT
TEMP DIFFERENCE BETWEEN THE OCEAN AND H85.
SO OVERALL...NOT CONFIDENT ON SIGNIFICANT SNOW OUTCOMES. SOME LIGHT
SNOW APPEARS PLAUSIBLE FOR AREAS S/E...BUT AT THIS TIME DO NOT FEEL
CONFIDENT CONCERNING ANY HEADLINES. MAJORITY OF HEAVY SNOW / SNOW-
BANDING REMAINS EAST AND OFFSHORE. COULD SEE SOME MIXING WITH RAIN
ACROSS CAPE COD AND THE ISLANDS.
OTHERWISE WINDS ARE OF CONCERN. BOMBING LOW TOWARDS NOVA SCOTIA...
BY LATE SATURDAY WILL INVOKE STRONG W/NW FLOW. AROUND 40 MPH WEST
WINDS 2 KFT AGL POSSIBLE BY EVENING. MIXING MAY PRECLUDE ACROSS THE
INTERIOR...BUT NOT SO MUCH THE CASE NEAR THE WATERS. WIND HEADLINES
MAY NEED TO BE CONSIDERED.
SATURDAY NIGHT THROUGH SUNDAY NIGHT...
WILL SEE BRISK W/NW WINDS BEHIND THE DEPARTING MATURING LOW WELL
EAST ACROSS NOVA SCOTIA. WIND HEADLINES MAY NEED TO BE CONSIDERED
SATURDAY NIGHT INTO SUNDAY MORNING WITH 40-50 MPH W/NW WINDS 2 KFT
AGL /ESPECIALLY CLOSER TO THE WATERS WITH STEEP LAPSE RATES UP TO
H9/. AT LEAST GALES OVER THE WATERS WITH THE THREAT OF FREEZING
SPRAY. SOME UNCERTAINTY HAS TO HOW EFFECTIVELY WINDS MIX-DOWN.
WINDS DIMINISHING DURING THE DAY SUNDAY BY LATE OF WHICH AN ARCTIC
COLD FRONT WILL BRING A SURGANCE OF COLDER AIR INTO THE NE CONUS.
HIGH PRES FILTERS IN THEREAFTER BRINGING A PERIOD OF QUIET WEATHER.
NEXT WEEK...
NO CONFIDENCE IN THE FORECAST. ANOTHER STORM IS ANTICIPATED TO SWEEP
ACROSS THE REGION THE DETAILS AND TIMING OF WHICH REMAIN UNCERTAIN.
THOUGH A QUICK COLD SHOT IS EXPECTED BEHIND THE STORM...A WARMER-
TREND IS PREFERRED INTO THE LATER-HALF OF FEBRUARY.
&&
.AVIATION /06Z THURSDAY THROUGH MONDAY/...
LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.
SHORT-TERM /THROUGH TONIGHT/...MODERATE CONFIDENCE.
CONDITIONS DETERIORATING TO IFR-LIFR 10-14Z FROM SOUTH TO NORTH
AS SNOW OVERSPREADS THE REGION WITH LOW CONDITIONS PERSISTING
THROUGH TONIGHT. BAND OF HEAVY SNOW LIKELY LIFTING NORTH FROM
THE S COAST AROUND 12Z. TRANSITION TO RAIN EXPECTED ACK BY 13Z
REACHING PVD-BOS AROUND 18Z WITH SNOW TO THE NORTH AND WEST. AS
WARMER MOVES IN ALOFT...TRANSITION TO SLEET AND FZRA EXPECTED TO
REACH INLAND TO BDL-ORH-MHT THIS EVENING. PRECIP MAY LIGHTEN UP
THIS EVENING FOR A TIME AS DRY SLOT MOVES IN...BUT EXPANSION OF
PRECIP EXPECTED LATER TONIGHT AS DEEPENING MID LEVEL LOW LIFTS
ACROSS THE REGION.
AS FOR WINDS...STRONG EAST WINDS WITH GUSTS UP TO 40 KTS FOR
SOUTH-SHORELINE TERMINALS THIS AFTERNOON. WILL SEE THOSE WINDS
MIGRATE NORTHWARD IMPACTING EAST COAST TERMINALS LATE TODAY AND
TONIGHT WITH MAIN FOCUS ACROSS NE MA TONIGHT. LLWS EXPECTED ASSOCD
WITH THE LOW LEVEL JET.
KBOS TERMINAL...MODERATE CONFIDENCE IN TIMING OF PRECIP
TRANSITION. IFR/LIFR
KBDL TERMINAL...MODERATE CONFIDENCE IN TAF.
OUTLOOK...FRIDAY THROUGH SUNDAY NIGHT...
FRIDAY...MODERATE CONFIDENCE.
MVFR-IFR WITH -SN IMPROVING VFR LATE IN THE DAY. BLUSTERY W/NW FLOW
STRONGEST FOR SHORELINE TERMINALS 30-35 KTS /UP TO 40 KTS FOR ACK/.
POSSIBLE LLWS IMPACTS WITH 30-40 KT WEST FLOW 2 KFT AGL.
FRIDAY NIGHT INTO SATURDAY...MODERATE CONFIDENCE.
RETURN MVFR-IFR WITH -SN ASSOC WITH OFFSHORE STORM MIXING WITH -RA
OVER CAPE/ISLANDS. N/NW WINDS BACKING W/NW AND INCREASING LATE 25-30
KTS WITH LLWS IMPACTS POSSIBLE.
SATURDAY NIGHT INTO SUNDAY NIGHT...HIGH CONFIDENCE.
IMPROVING VFR. BLUSTERY W/NW WINDS AROUND 30 KTS FOR E/SE SHORE
OVERNIGHT...LESSENING INTO SUNDAY. LLWS IMPACTS CONTINUE FOR THE
EARLY HALF OF THE PERIOD.
&&
.MARINE...
FORECASTER CONFIDENCE LEVELS...
LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.
MODERATE CONFIDENCE THROUGH THURSDAY NIGHT...
7 PM UPDATE...
WINDS ACROSS THE WATERS THURSDAY INTO THURSDAY NIGHT WILL BE NEAR
STORM-FORCE. GALE WARNINGS IN PLACE BUT MAY NEED TO BE UPGRADED.
PREVIOUS DISCUSSION...
TONIGHT...BUILDING WINDS AND SEAS. VALUES ON THE SOUTHERN OUTER
WATERS MAY REACH 25 KNOTS/5 FEET BY MORNING.
THURSDAY AND THURSDAY NIGHT...EAST WINDS CONTINUE TO INCREASE
THROUGH THE DAY WITH SUSTAINED WINDS REACHING NEAR 30 KNOTS ON THE
SOUTH COAST BY AFTERNOON AND ALONG THE EAST COAST LATE IN THE DAY.
WINDS AT 2000 FEET ABOVE THE WATERS WILL REACH 50-55 KNOTS...AND
SOME OF THIS MAY BE DRAGGED TO THE OCEAN SURFACE IN FREQUENT GALE
FORCE GUSTS DURING PRECIPITATION. SEAS WILL BUILD THROUGH THE
DAY... REACHING 10-15 FEET ON THE SOUTHERN WATERS BY AFTERNOON AND
15 TO 18 FEET ON THE EASTERN WATERS BY EVENING.
WINDS MAY BRIEFLY DIMINISH THURSDAY NIGHT AS THE LOW PRESSURE
CENTER MOVES ACROSS THE CAPE AND ISLANDS. OTHERWISE EXPECT WINDS
AT OR NEAR GALE FORCE THROUGH THURSDAY NIGHT. GALE WARNING
CONTINUES FOR THIS PERIOD.
OUTLOOK...FRIDAY THROUGH SUNDAY...
FRIDAY...MODERATE CONFIDENCE.
BLUSTERY W/NW FLOW AROUND 35 KTS INITIALLY. GALES LIKELY...AND THE
GALE WARNING HAS BEEN CONTINUED INTO THIS PERIOD. MAY NEED TO
CONSIDER STORMS. GREATEST SEAS SE 12 TO 17 FEET. BOTH WIND AND
WAVES BEGIN TO DIMINISH TOWARDS LATE.
FRIDAY NIGHT INTO SATURDAY...MODERATE CONFIDENCE.
WIND AND WAVE ACTION DIMINISHING THROUGH A MAJORITY OF THE PERIOD.
WEST WINDS 25-30 KTS EARLY. N/NW WINDS BY MIDDAY BACKING W/NW AND
INCREASING LATE 25-30 KTS BY EVENING. SEAS BEGINNING TO BUILD AGAIN.
SATURDAY NIGHT INTO SUNDAY NIGHT...HIGH CONFIDENCE.
BLUSTERY W/NW WINDS AROUND 30 KTS SATURDAY NIGHT...DIMINISHING
THROUGH THE REST OF THE PERIOD. SEAS BUILDING AROUND 8 FEET ON THE
OUTER WATERS /MORESO SOUTH AND EAST/. COMBINATION OF WINDS AND
COLDER AIR SURGING OVER THE WATERS PRESENTS THE THREAT OF FREEZING
SPRAY MAINLY SATURDAY NIGHT INTO SUNDAY.
&&
.TIDES/COASTAL FLOODING...
LOW ASTRONOMICAL HIGH TIDES SHOULD PRECLUDE A SIGNIFICANT COASTAL
FLOOD RISK WITH THE THU/THU NIGHT STORM. NONETHELESS...WE BELIEVE
THAT A 2 TO 2.5 FT SURGE WITH WAVES 15 TO 20 FT JUST OFFSHORE MAY
OCCUR AND THAT WOULD BE ENOUGH FOR POCKETS OF MINOR COASTAL FLOODING
AND SOME EROSION FROM SALISBURY TO CAPE ANN AND HULL TO PLYMOUTH
ALONG E COASTAL MA FOR THE LATE THU EVENING HIGH TIDE. A COASTAL
FLOOD ADVISORY MAY BE NEEDED FOR THOSE TWO REACHES OF COASTLINE BUT
STILL ENOUGH TIME TO ALLOW THE OVERNIGHT SHIFT TO REASSESS BEFORE
RELEASING ANY PRODUCT. IN PARTICULAR...THE CORE OF THE LOW LEVEL JET
AROUND TIME OF HIGH TIDE...GENERALLY 1030 TO 11 PM EST...LOOKS TO BE
POINTED TOWARD IPSWICH BAY...TAKING A CONSENSUS OF MODELS.
THUS...THE SALISBURY TO CAPE ANN SHORELINE STRETCH IS THE REGION
MOST SUSCEPTIBLE TO AN EROSION IMPACT. ETSS AND ESTOFS GUIDANCE
VALUES ARE FAIRLY CLOSE TO EACH OTHER BUT RAISED VALUES GENERALLY .5
TO .8 FT ALONG E COASTAL MA BASED ON SYNOPTIC PATTERN RECOGNITION
AND PAST EXPERIENCE WITH THE SURGE GUIDANCE.
&&
.BOX WATCHES/WARNINGS/ADVISORIES...
CT...WINTER STORM WARNING FROM 7 AM THIS MORNING TO 7 AM EST FRIDAY
FOR CTZ002>004.
MA...WINTER STORM WARNING FROM 7 AM THIS MORNING TO 7 AM EST FRIDAY
FOR MAZ002>006-008>014-026.
WIND ADVISORY FROM 11 AM THIS MORNING TO 7 PM EST THIS EVENING
FOR MAZ020>024.
WINTER WEATHER ADVISORY FROM 7 AM THIS MORNING TO 7 AM EST
FRIDAY FOR MAZ007-015>021.
WIND ADVISORY FROM 2 PM THIS AFTERNOON TO MIDNIGHT EST TONIGHT
FOR MAZ007-014>016-019.
NH...WINTER STORM WARNING FROM 7 AM THIS MORNING TO 7 AM EST FRIDAY
FOR NHZ011-012-015.
RI...WINTER STORM WARNING FROM 7 AM THIS MORNING TO 7 AM EST FRIDAY
FOR RIZ001-003-006.
WIND ADVISORY FROM 11 AM THIS MORNING TO 7 PM EST THIS EVENING
FOR RIZ007-008.
WINTER WEATHER ADVISORY FROM 7 AM THIS MORNING TO 7 AM EST
FRIDAY FOR RIZ002-004-005-007.
MARINE...GALE WARNING FROM 10 AM THIS MORNING TO 5 PM EST FRIDAY FOR
ANZ231>235-237-250-251.
GALE WARNING FROM NOON TODAY TO 5 AM EST FRIDAY FOR ANZ230.
GALE WARNING FROM NOON TODAY TO 7 PM EST THIS EVENING FOR
ANZ236.
GALE WARNING FROM 7 AM THIS MORNING TO 5 PM EST FRIDAY FOR
ANZ254>256.
&&
$$
SYNOPSIS...WTB/SIPPRELL
NEAR TERM...KJC/SIPPRELL
SHORT TERM...WTB
LONG TERM...SIPPRELL
AVIATION...KJC/SIPPRELL
MARINE...WTB/SIPPRELL
TIDES/COASTAL FLOODING...
AREA FORECAST DISCUSSION
NWS MOUNT HOLLY NJ
1147 AM EST THU FEB 13 2014
.SYNOPSIS...
LOW PRESSURE LOCATED OFF THE NORTH CAROLINA COAST EARLY THIS MORNING
WILL MOVE NORTHEAST ALONG THE COAST THROUGH FRIDAY. LATER FRIDAY...
ANOTHER COLD FRONTAL SYSTEM WILL MOVE INTO THE MIDWEST WHICH WILL
SWING THROUGH OUR REGION FRIDAY NIGHT AND SATURDAY. HIGH PRESSURE
WILL BUILD INTO THE REGION FOR SUNDAY AND MONDAY WITH A CLIPPER
SYSTEM TRACKING SOUTH OF THE REGION. ANOTHER LOW PRESSURE SYSTEM
WILL APPROACH THE REGION TUESDAY AND WEDNESDAY OF NEXT WEEK.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
THE DRY SLOT IS WORKING ITS WAY INTO OUR CWA. ITS MORE OBVIOUS ON
THE LAPS SOUNDINGS IN THE SOUTHWEST PART OF OUR CWA. SO FOR THIS
AFTERNOON IN THE LOWER HALF OF OUR CWA MAINLY RAIN AND SLEET WHERE
SFC TEMPS ARE ABOVE FREEZING (AROUND I95 SOUTHEAST), AND A LIGHTER
WINTRY MIX WEST OF PHILADELPHIA.
IN THE NORTHERN PART OF OUR CWA, THE HRRR PASSES THE HEAVY SNOW
BAND THRU OUR CWA BY ABOUT 18Z-19Z, WITH LIGHTER SNOW (POSSIBLY
MIXED WITH SLEET) CONTINUING THE REST OF THE AFTERNOON.
NO BIG CHANGES TO TEMPERATURES. WRONGLY CONCLUDED THAT THE PCPN
INDUCED INVERSION WOULD KEEP STRONG WINDS FROM MIXING NEAR THE
COAST. LATEST MESONET SITES ARE SHOWING THAT THE PEAK GRADIENT
PERIOD HAS PASSED.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 AM FRIDAY/...
THE ENDING TIME OF THE PRECIPITATION CONTINUES TO SLIP FARTHER
AWAY...NOW INTO FRIDAY MORNING FOR THE FAR NE. THE DEFORMATION
ZONE SNOW BEHIND THE SYSTEM WILL MAKE FOR ANOTHER PERIOD OF DECENT
ACCUMS ACROSS NJ/ERN PA TONIGHT. THE ENDING TIMES OF THE WSW FLAGS
MAY BE ADJUSTED LATER...WHEN THE TIMING BECOMES MORE CERTAIN.
GUSTY N/NW WINDS TONIGHT. TEMPERATURES DROPPING INTO THE 20S...LOW
20S NORTH...MID/UPPER 20S SOUTH.
&&
.LONG TERM /FRIDAY THROUGH WEDNESDAY/...
LONG TERM PART OF THE FORECAST WAS NOT CHANGED OVERNIGHT...THE
PREVIOUS DISCUSSION IS BELOW.
FRIDAY: THE MAJOR WINTER STORM WILL BE DEPARTING OUR REGION AND
WE SHOULD SEE A DECREASE IN CLOUDS WITH A CONTINUED WESTERLY FLOW
BEHIND THE STORM. LEFT IN A SLIGHT CHANCE POP ACROSS THE NORTH FOR
ANY LINGERING MORNING PRECIPITATION. NOT MUCH IN THE WAY OF COLD
AIR ADVECTION BEHIND THE STORM WITH 850 MB TEMPS NOT FALLING MUCH
BELOW ZERO. AS A RESULT TEMPERATURES DO STAND A GOOD CHANCE TO
RISE INTO THE MID AND UPPER 30`S. DID GO COLDER THAN MEX/MOS
GUIDANCE DUE TO THE SNOW COVER AND SOME MORNING CLOUDS.
FRIDAY NIGHT AND SATURDAY: WE HAVE YET ANOTHER FRONTAL BOUNDARY
MOVING THROUGH THE REGION WITH AN ASSOCIATED LOW PRESSURE SYSTEM
TRACKING SOUTH OF THE REGION. THIS WILL BRING A FRESH SHOT OF MID-
LEVEL COLD AIR INTO THE REGION. SURFACE TEMPERATURES WILL TAKE
LONGER TO COOL OFF AND MAY STAY RATHER STEADY SATURDAY WITH COLD
AIR ADVECTION BEHIND THE FRONT. THIS MEANS ANY PRECIPITATION WOULD
BE IN THE FORM OF SNOW OR A RAIN/SNOW MIX DOWN SOUTH. THE 12Z GFS
ALONG WITH THE CMC ARE STARTING TO FOCUS ON A SHORTWAVE BEING A
BIT STRONGER FRIDAY OVER THE MID-SOUTH AND MOVING NORTHEAST. THIS
GOES WITH THE ECMWF WHICH HAS BEEN SHOWING THIS FOR A FEW RUNS
NOW. THE 15Z SREF IS NOT YET PICKING UP ON THIS FEATURE BUT WPC
AND THE AFTERNOON MODEL GUIDANCE PROVIDE A NICE FEEL FOR HOW MUCH
PRECIPITATION WILL FALL. OVERALL THIS COULD BRING ANOTHER INCH OF
SNOW TO AREAS SOUTH AND EAST OF PHILADELPHIA WITH UNDER AN INCH TO
THE NORTH. TEMPERATURES BELOW FREEZING MAY LEAD TO SLICK SPOTS
SATURDAY MORNING. WENT MORE TOWARD THE 12Z GFS AND THE ECMWF SUITE
FOR TEMPERATURES IN THIS PERIOD, MEX A LITTLE TO WARM.
SATURDAY NIGHT THOROUGH MONDAY: THIS IS ANOTHER COLD LOOKING
PERIOD. 850 MB TEMPS WILL DIVE TO AROUND -10C WITH STRONG COLD AIR
ADVECTION CONTINUING, WEST TO NORTHWEST FLOW. THIS WILL LIKELY
KEEP TEMPERATURES WELL BELOW FREEZING SUNDAY WILL GO MORE TOWARD
TO THE ECMWF SUITE FOR TEMPERATURES ON SUNDAY WHICH MATCHES UP
WELL WITH WPC. MODELING HAS BEEN CONSISTENT IN A BRINGING A WEAK
CLIPPER SYSTEM TO OUR SOUTH IN THE SUNDAY TIME FRAME AS WELL WHICH
MAY INCREASE CLOUDS WITH ANOTHER CHANCE OF LIGHT SNOW/FLURRIES
FOCUSED ACROSS THE DELMARVA. ONCE AGAIN THE RAW TWO METER
TEMPERATURES AT THE TIME WHEN THE HIGH PRESSURE WOULD BE OVERHEAD
SUNDAY NIGHT LOOK A LITTLE LOW ON THE EC AS IT ASSUMES SNOW COVER,
WHILE THE MEX AND OTHER STAT GUIDANCE ARE LIKELY TO HIGH.
MONDAY NIGHT THROUGH WEDNESDAY: THIS SHOULD BE A MODERATING
PERIOD AS THE HIGH PRESSURE MOVES EAST. A RECENT RARE OCCURRENCE
OF SOUTHERLY FLOW WOULD THEN ENSUE ALLOWING FOR A MODERATING TREND
AHEAD OF THE NEXT SYSTEM. THIS SYSTEM LOOKS TO CUT WELL INTO THE
LAKES/OH VALLEY RESULTING IN A WINTRY MIX TRANSITIONING TO RAIN.
THIS PERIOD MAY ALSO REQUIRE A NON-DIURNAL TEMPERATURE TREND
MONDAY NIGHT AS WELL. IN ADDITION THIS SYNOPTIC SET-UP MAY BRING A
CHANCE FOR FREEZING RAIN AS WELL. FOR NOW HAVE LEFT IT OUT OF THE
FORECAST WITH SEVERAL DAYS TO LOOK AT THIS FURTHER.
LONGER RANGE: THERE IS CURRENTLY COOLING PROJECTED AT 10 MB IN
THE STRATOSPHERE SUPPORTIVE OF +AO +NAO. A RETURN TO A MORE
POSITIVE EPO AS WELL MAY PROVIDE A WARM PERIOD RELATIVE TO NORMAL
JUST BEYOND OUR SEVEN DAY WINDOW. THE CFS WEEKLIES ARE ALSO
SHOWING THIS WARM PERIOD. SO HANG IN THERE IF YOU ARE TIRED OF THE
SNOW AND CONTINUED COLD.
&&
.AVIATION /18Z THURSDAY THROUGH TUESDAY/...
THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG, KILG,
KMIV, KACY AND SURROUNDING AREAS.
SOUTHERN TAF SITES, INCLUDING PHL AND ILG, HAVE NOW CHANGED OVER
TO RAIN. WINDS ARE GUSTING UP TO 35 KT AT MOST SITES, EXCEPT A
LITTLE HIGHER ALONG THE COAST, A LITTLE LOWER IN THE LEHIGH
VALLEY. EXPECT CONDITIONS TO BE JUST A BIT BETTER THIS AFTERNOON
AS A DRY SLOT MOVES NORTH. TAFS ARE BEING UPDATED AS FREQUENTLY AS
POSSIBLE TO KEEP ABREAST WITH CHANGING CONDITIONS. JUST A MESSY
DAY AVIATION-WISE.
EXPECT GUSTY WINDS TO CONTINUE INTO A GOOD PORTION OF THE
OVERNIGHT HOURS...FROM THE NORTHEAST TODAY INTO THIS EVENING, THEN
GOING NORTH, THEN NORTHWEST LATE THIS EVENING. GUSTS WILL CONTINUE
IN THE 35KT PLUS RANGE AS THE STORM CONTINUES TO DEEPEN EVEN AS IT
MOVES AWAY. THE DRY SLOT ASSOCIATED WITH THIS SYSTEM SHOULD GIVE
US A SLIGHT BREAK IN THE PCPN THIS AFTERNOON BEFORE THE NEXT ROUND
MOVES IN LATE THIS AFTERNOON...FIRST AS RAIN, THEN SNOW.
FOR FRIDAY...CONDITIONS WILL BECOME VFR EARLY AND CLOUDS WILL
START TO DISSIPATE. WINDS WILL GRADUALLY DECREASE BUT REMAIN GUSTY
OUT OF THE WEST THROUGH MUCH OF THE DAY.
OUTLOOK...
FRIDAY NIGHT: INCREASING CLOUDS WITH LIGHT SNOW DEVELOPING
CONDITIONS DETERIORATING TO MVFR AND IFR.
SATURDAY: MVFR AND IFR CONDITIONS WITH LIGHT SNOW IN THE MORNING
IMPROVING TO VFR IN THE AFTERNOON.
SATURDAY NIGHT THROUGH MONDAY: VFR INCREASING CLOUDS LATE MONDAY.
&&
.MARINE...
A GALE WARNING REMAINS IN EFFECT FOR ALL AREA WATERS.
LOW PRESSURE WILL CONTINUE TO PUSH UP THE COAST TODAY. NORTHEAST
WINDS WILL CONTINUE TO GUST THROUGH THE DAY AND INTO FRIDAY, WITH
GUSTS UP TO 45 KNOTS. WINDS WILL SUBSIDE A BIT THIS EVENING BUT
WILL REMAIN GUSTY OVERNIGHT.
SEAS WILL CONTINUE TO INCREASE THROUGH THE DAY AND REACH UP TO 11
FEET ON THE OCEAN WATERS BEFORE STARTING TO SUBSIDE LATE
TONIGHT/EARLY FRIDAY.
OUTLOOK...
FRIDAY AND FRIDAY NIGHT: GALE WARNING EXTENDED TO 15Z WITH THE
HIGHEST GALE FORCE GUSTS 35 TO LOCALLY 40 KTS TO BE RIGHT AROUND
12Z. SEAS WILL REMAIN OVER 5 FEET THROUGHOUT MOST OF FRIDAY WITH A
CONTINUATION OF SCA CONDITIONS LIKELY AFTER THE GALE WARNING
TIME FRAME SUBSIDING FRIDAY EVENING.
SATURDAY AND SATURDAY NIGHT: ANOTHER PERIOD OF SCA SEAS WITH WIND
GUSTS AROUND 20 KNOTS.
SUNDAY AND MONDAY: SEAS AND WINDS WILL REMAIN BELOW SCA CRITERIA.
&&
.TIDES/COASTAL FLOODING...
THE STRONG COASTAL STORM IS EXPECTED TO AFFECT THE AREA TODAY AND
TONIGHT. AREAS OF MINOR COASTAL FLOODING ARE EXPECTED ALONG THE
NEW JERSEY AND DELAWARE COASTS, AS WELL AS THE DELAWARE BAY. THE
HIGHEST ASTRONOMICAL TIDE IS EXPECTED TO BE SHORTLY AFTER DAWN
TODAY, BUT THE HIGHEST TIDAL DEPARTURES ARE EXPECTED TO OCCUR
WITH THE THURSDAY EVENING HIGH TIDE.
COASTAL FLOODING IS NOT CURRENTLY EXPECTED ALONG THE EASTERN
SHORE OF THE CHESAPEAKE BAY.
&&
.CLIMATE...
CONGRATULATIONS TO PHL, AN HISTORICAL FOURTH SIX INCH OR GREATER
SNOW EVENT IN ONE SINGLE SEASON.
WE WERE ABLE TO RUN THE CLIMATE THIS MORNING. ALL CLI AND CF6
PRODUCTS ARE NOW UP TO DATE.
&&
.PHI WATCHES/WARNINGS/ADVISORIES...
PA...WINTER STORM WARNING UNTIL 6 AM EST FRIDAY FOR PAZ054-055-
060>062-070-071-101>106.
NJ...WINTER STORM WARNING UNTIL 6 AM EST FRIDAY FOR NJZ001-007>010-
012>022-027.
COASTAL FLOOD ADVISORY UNTIL MIDNIGHT EST TONIGHT FOR
NJZ012>014-016-020>027.
WINTER WEATHER ADVISORY FROM 4 PM THIS AFTERNOON TO 6 AM EST
FRIDAY FOR NJZ023>026.
DE...WINTER STORM WARNING UNTIL 6 AM EST FRIDAY FOR DEZ001-002.
COASTAL FLOOD ADVISORY UNTIL MIDNIGHT EST TONIGHT FOR
DEZ001>004.
WINTER WEATHER ADVISORY FROM 4 PM THIS AFTERNOON TO 6 AM EST
FRIDAY FOR DEZ003-004.
MD...WINTER STORM WARNING UNTIL 6 AM EST FRIDAY FOR MDZ008-012-015-
019-020.
MARINE...GALE WARNING UNTIL 10 AM EST FRIDAY FOR ANZ450>455.
GALE WARNING UNTIL 6 PM EST THIS EVENING FOR ANZ430-431.
&&
$$
SYNOPSIS...GAINES
NEAR TERM...GIGI
SHORT TERM...O`HARA
LONG TERM...GAINES/O`HARA
AVIATION...GAINES/MEOLA/MIKETTA
MARINE...GAINES/MEOLA
TIDES/COASTAL FLOODING...
CLIMATE...
AREA FORECAST DISCUSSION
NWS TAMPA BAY RUSKIN FL
700 PM EST FRI FEB 14 2014
.UPDATE (TONIGHT THROUGH SATURDAY)...
00Z WATER VAPOR AND H4 RAP ANALYSIS SHOWING AN ALREADY AMPLIFIED
UPPER LEVEL PATTERN OVER THE CENTRAL AND EASTERN CONUS BECOMING EVEN
MORE AMPLIFIED AS THE NEXT SIGNIFICANT EAST COAST TROUGH BEGINS TO
TAKE SHAPE. THE MAIN SHORTWAVE IMPULSE THAT WILL RESULT IN THIS
AMPLIFICATION IS CURRENTLY DROPPING TO THE SOUTHEAST OVER THE TN
VALLEY. DISTINCT DRYING/SUBSIDENCE IN ITS WAKE CONFIRM THAT THIS IS
A RATHER VIGOROUS PIECE OF ENERGY. CLOSER TO HOME...THE FLORIDA
PENINSULA IS EMBEDDED IN DEEP CYCLONIC FLOW WITH THE MAIN LONGWAVE
TROUGH COVERING THE EASTERN HALF OF THE NATION. FAIRLY DRY COLUMN IN
PLACE OVER OUR HEADS THIS EVENING WITH JUST SOME WEAK INFLUX OF HIGH
LEVEL MOISTURE NOTED ON WV IMAGERY.
AT THE SURFACE...WEAK HIGH PRESSURE THAT WAS IN CONTROL THROUGH
FRIDAY...IS BEGINNING TO RETREAT SOUTHWARD IN RESPONSE TO A
STRENGTHENING COLD FRONT OFF TO OUR NORTHWEST. THIS FRONT TRAILS
BACK TO THE SOUTHWEST ACROSS THE DEEP SOUTH FROM A CLOSED LOW OVER
TN/KY. THIS LOW REPRESENTS THE SURFACE REFLECTION FROM THE VIGOROUS
UPPER LEVEL SHORTWAVE ABOVE AND IS FORECAST TO REALLY "TAKE OFF" IN
TERMS OF DEEPENING ONCE THE SYSTEM REACHES THE ATLANTIC WATERS OFF
THE MID-ATLANTIC/NEW ENGLAND COASTLINE DURING SATURDAY. LOOKS LIKE
ANOTHER SNOWSTORM TOMORROW FOR PARTS OF THE NORTHEAST. WINTER DOES
NOT WANT TO QUIT FOR THOSE FOLKS. BUT...BACK TO OUR WEATHER...
REST OF TONIGHT...GRADIENT WILL SLOWLY BE TIGHTENING AS THE COLD
FRONT APPROACHES FROM GA/FL BIG BEND LATE TONIGHT. INITIALLY THE
LIGHT FLOW AND DRY COLUMN SHOULD ALLOW TEMPERATURES TO DROP PRETTY
QUICKLY...AND IT WILL CERTAINLY HAVE A COOL FEEL ONCE THE SUN SETS.
HOWEVER...NOT ANTICIPATING ANY FROST ISSUES LIKE WE HAD LAST NIGHT
SINCE THE RADIATIVE PROCESS WILL EVENTUALLY BE STOPPED BY THE
TIGHTENING GRADIENT...WHICH SHOULD BREAK ANY BOUNDARY LAYER
DE-COUPLING THAT HAS ALREADY OCCURRED. OVERALL MOISTURE RETURN AHEAD
OF THIS FRONT IS MARGINAL TO SAY THE LEAST. HOWEVER...AS MENTIONED
IN THE PREVIOUS DISCUSSION...THE DEGREE OF SYNOPTIC SUPPORT FOR
ASCENT WITH THE STRONG SHORTWAVE PASSING BY COMBINED WITH THE
FRONTOGENETIC NATURE OF THE BOUNDARY AS IT ARRIVES TOWARD
LEVY/CITRUS/SUMTER COUNTY SUGGESTS A NARROW BUT HEALTHY BAND OF
SHOWERS WILL BE ARRIVING OVER THESE NORTHERN ZONES TOWARD DAWN.
GFS/ECMWF BOTH HAVE A VERY IMPRESSIVE SWATH OF DEEP LAYER QVECTOR
CONVERGENCE PASSING THROUGH NORTH FLORIDA IN THE LATE NIGHT/EARLY
MORNING HOURS AND FEEL THE HIGH CHANCE TO LIKELY POPS IN THE
FORECAST FOR OUR NORTHERN ZONES CONTINUES TO BE JUSTIFIED. THIS IS
CLASSIC SITUATION WHERE STATISTICAL MOS JUST WILL NOT CUT IT. THE
DRY COLUMN OVERWHELMS THE EQUATIONS AND YOU GET THE LOW STATISTICAL
RAIN CHANCES. IN CONTRAST TO THE LOW STATISTICAL RAIN
CHANCES...COULD NOT FIND A SINGLE HIGH RESOLUTION CONVECTION
ALLOWING MODEL FROM THIS OFFICE...NCEP...OR SURROUNDING OFFICES
WHICH DID NOT SHOW MEASURABLE PRECIP INTO THE NATURE COAST. DO KEEP
IN MIND THAT NONE ARE ALSO PRODUCING SIGNIFICANT RAIN...AND ALL SHOW
A VERY THIN BAND OF CONVECTION. LOOKS LIKE A BRIEF AND LOW IMPACT
EVENT...1/10TH OF AN INCH OR LESS FOR MOST SPOTS.
SATURDAY...
THE COLD FRONT WILL MAKE QUICK PROGRESS SOUTHWARD ACROSS THE
FORECAST AREA DURING THE DAYLIGHT HOURS. THE OVERALL TREND WILL BE
FOR THE THIN LINE OF SHOWERS TO SLOWLY BECOME MORE
DISORGANIZED/BROKEN THROUGH THE MORNING/EARLY AFTERNOON AS IT PASSES
THROUGH THE I-4 CORRIDOR. UPPER LEVEL SUPPORT WILL BE FADING AS THE
SHORTWAVE AXIS PIVOTS TO OUR NORTHEAST...LEAVING ONLY THE LOW LEVEL
FRONTAL FOCUS FOR ASCENT. WILL PROB SEE A FEW SCT SHOWERS HOLDING ON
TO PASS THROUGH THE I-4 CORRIDOR LATER MORNING/MIDDAY...AND THEN
ANTICIPATE ONLY ISOLATED ACTIVITY FURTHER SOUTH DOWN THE
SUNCOAST/INTERIOR SOUTH-CENTRAL COUNTIES. WILL SEE A QUICK CLEARING
BEHIND THE FRONT WITH A GUSTY AND COOL NORTHWEST WIND. WILL LIKELY
BE A BIT ROUGH FOR THE AFTERNOON ON AREA LAKES AND A LAKE WIND
ADVISORY MAY BE REQUIRED.
SO...WE HAVE TO GET THROUGH ONE MORE COLD FRONT...AND A FEW QUICK
SHOWERS ON SATURDAY...AND THEN WE BEGIN AN EXTENDED PERIOD OF DRY
WEATHER...WHICH LOOKS TO LAST THROUGH THE MAJORITY (IF NOT ALL) OF
NEXT WEEK. SATURDAY NIGHT/EARLY SUNDAY WILL BE A BIT CHILLY...AND
SOME CONCERN FOR ANOTHER ROUND OF FROST/LIGHT FREEZE FOR THE NATURE
COAST ZONES...BUT THEN TEMPERATURES WILL STEADILY MODERATE BACK TO
NORMAL AND ABOVE NORMAL LEVELS FOR MUCH OF NEXT WEEK. ENJOY AND HAVE
A GREAT FRIDAY EVENING EVERYONE!
&&
.AVIATION...
15/00Z-16/00Z. APPROACHING FRONT BRINGS LATE NIGHT MVFR CIGS...
VCSH...AND GUSTY SW WINDS FOR THE NORTHERN TERMINALS. THE FRONT
CLEARS THOSE TERMINALS MID MORNING AND CONTINUES SOUTH AS IT
WEAKENS. PGD WILL SEE MVFR CIG AND LATE MORNING VCSH WHILE FMY AND
RSW ONLY HAVE MVFR CIGS. WINDS SHIFT TO NW BEHIND THE FRONT AND STAY
GUSTY FOR MOST OF THE DAY.
&&
.MARINE...
A COLD FRONT WILL APPROACH FROM THE WEST TONIGHT AND MOVE THROUGH
THE AREA ON SATURDAY. WINDS WILL INCREASE TO ADVISORY LEVELS NORTH
OF ENGLEWOOD TONIGHT AND TO EXERCISE CAUTION LEVELS SOUTH OF
ENGLEWOOD. SMALL CRAFT ADVISORIES OR EXERCISE CAUTION HEADLINES WILL
LIKELY BE NEEDED FOR ALL AREAS ON SATURDAY. HIGH PRESSURE WILL THEN
BUILD BACK INTO THE REGION SATURDAY NIGHT AND REMAIN THE DOMINANT
WEATHER FEATURE THROUGH MUCH OF NEXT WEEK WITH WINDS AND SEAS
REMAINING BELOW ADVISORY LEVELS.
&&
.PRELIMINARY POINT TEMPS/POPS...
TPA 53 67 45 68 / 0 50 0 0
FMY 54 73 47 74 / 0 10 0 0
GIF 51 70 43 70 / 0 40 0 0
SRQ 54 67 46 67 / 0 30 0 0
BKV 45 65 36 69 / 10 50 0 0
SPG 57 66 51 68 / 0 50 0 0
&&
.TBW WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
GULF WATERS...SMALL CRAFT ADVISORY FROM 1 AM TO 4 PM EST SATURDAY FOR
ENGLEWOOD TO TARPON SPRINGS OUT 20 NM-TAMPA BAY
WATERS-TARPON SPRINGS TO SUWANNEE RIVER OUT 20 NM.
SMALL CRAFT ADVISORY FROM 10 PM THIS EVENING TO 4 PM EST
SATURDAY FOR ENGLEWOOD TO TARPON SPRINGS OUT 20 TO 60
NM-TARPON SPRINGS TO SUWANNEE RIVER OUT 20 TO 60 NM.
&&
$$
UPDATE...MROCZKA
AVIATION...RUDE
AREA FORECAST DISCUSSION
NWS COLUMBIA SC
637 AM EST THU FEB 13 2014
.SYNOPSIS...
LOW PRESSURE NEAR THE CAROLINA COAST WILL MOVE NORTHEASTWARD
TODAY. WINTRY PRECIPITATION WILL END FROM SOUTHWEST TO NORTHEAST.
A DRY WESTERLY FLOW NORTH OF A PRESSURE RIDGE IN THE GULF OF
MEXICO WILL DOMINATE TONIGHT AND FRIDAY. A COLD FRONT WILL MOVE
THROUGH THE FORECAST AREA FRIDAY NIGHT FOLLOWED BY HIGH PRESSURE
SATURDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
MUCH OF THE FREEZING RAIN ASSOCIATED WITH THE H85 JET HAS SHIFTED
NORTHEAST OF THE FORECAST AREA. AREAS OF FREEZING RAIN AND DRIZZLE
ARE OCCURRING IN IT WAKE. LITTLE ADDITIONAL ICE ACCUMULATION IS
EXPECTED. THE MID-LEVEL DRY SLOT SHOULD BE SHORT LIVED BASED ON
SATELLITE TRENDS EARLY THIS MORNING. THE MODELS SHOW MOISTURE
BECOMING DEEPER AS THE UPPER TROUGH SHIFTS EASTWARD THIS MORNING.
THIS WRAP-AROUND MOISTURE WILL LIKELY CAUSE AN INCREASE IN
PRECIPITATION...ESPECIALLY IN THE NORTH PART. BELIEVE THE SNOW
THAT WAS IN PARTS OF ALABAMA AND NORTH GEORGIA WILL MOVE INTO THE
FORECAST AREA. THE NAM TIME-HEIGHT DISPLAYS SHOW MOISTURE GETTING
INTO THE SNOW-GROWTH ZONE AS THE COLD UPPER TROUGH MOVES OVER THE
AREA. THE HRRR SHOWS H85 TEMPERATURES COOLING TO BELOW FREEZING
FROM WEST TO EAST DURING THE MORNING. USED THIS GUIDANCE FOR THE
TRANSITION TIME OF PRECIPITATION CHANGING TO SNOW. EXPECT MOST OF
THE AREA WILL HAVE A PERIOD OF SNOW WITH THE MORE SIGNIFICANT
ADDITIONAL AMOUNTS IN THE NORTH PART WHERE MOISTURE WILL BE DEEPER.
AN AVERAGE OF THE NAM AND GFS QPF AND HPC GUIDANCE SUGGESTS SNOW
AMOUNTS OF 1 TO 2 INCHES IN THE NORTH PART...AND AN INCH OR LESS
ELSEWHERE.
THE LINGERING SNOW SHOULD END FROM SOUTH TO NORTH LATE THIS MORNING
AND EARLY THIS AFTERNOON. THE TEMPERATURE GUIDANCE APPEARS TOO
WARM BECAUSE OF THE ICE PACK. ALSO THE COLD UPPER TROUGH WILL BE
OVER THE FORECAST AREA FOR MUCH OF THE DAY.
A WINTER STORM WARNING REMAINS IN EFFECT THROUGH NOON.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM FRIDAY/...
A DRY WESTERLY FLOW NORTH OF THE GULF OF MEXICO PRESSURE RIDGE
WILL DOMINATE TONIGHT THROUGH FRIDAY. THE TEMPERATURE GUIDANCE IS
LIKELY TOO WARM BECAUSE OF THE DENSE ICE PACK.
&&
.LONG TERM /FRIDAY NIGHT THROUGH WEDNESDAY/...
A COLD FRONT WILL MOVE THROUGH THE FORECAST AREA FRIDAY NIGHT. THE
H85 WESTERLY FLOW SUGGESTED LITTLE MOISTURE WILL BE ASSOCIATED
WITH THIS FRONT. HOWEVER...THE ASSOCIATED MID-LEVEL SHORTWAVE
TROUGH WILL BE STRONG. AN AVERAGE OF THE NAM AND GFS MOS SUPPORT
POPS OF 30 TO 70 PERCENT WITH THE HIGHER VALUES IN THE NORTH PART
CLOSER TO THE STRONGER LIFT. MAINLY USED AN AVERAGE FOR THE POP
FORECAST EXCEPT DID NOT FORECAST QUITE LIKELY BECAUSE OF THE H85
WESTERLY FLOW. THERE MAY BE ENOUGH COOLING FOR A BRIEF MIX OF SNOW
IN THE NORTH PART. THE SYSTEM WILL BE PROGRESSIVE WITH MARGINAL
TEMPERATURES SO WE DO NOT EXPECT SIGNIFICANT SNOW.
THE GFS AND ECMWF SHOW DRY RIDGING DOMINATING DURING MOST OF THE
REMAINING MEDIUM-RANGE PERIOD. EXPECT LIMITED MOISTURE WITH A WEAK
FRONT MONDAY NIGHT OR TUESDAY. MODERATING TEMPERATURES SHOULD OCCUR.
THE GFS AND ECMWF MOS SUPPORT ABOVE NORMAL TEMPERATURES TUESDAY
AND WEDNESDAY.
&&
.AVIATION /12Z THURSDAY THROUGH MONDAY/...
UPPER LOW MOVING ACROSS NORTHERN GA EARLY THIS MORNING. LIGHT SNOW ON
THE BACK SIDE OF STRENGTHENING SURFACE COASTAL LOW WILL MOVE ACROSS
EASTERN GEORGIA INTO SC...AGS ALREADY REPORTING SNOW FLURRIES
13/1125Z. 850MB ZERO DEGREE ISOTHERM PUSHING EAST INTO WESTERN SC
NOW...WILL CONTINUE EASTWARD PROGRESSION ACROSS TAF SITES. WRAP
AROUND MOISTURE ALONG WITH COOLING TEMPERATURES ALOFT WILL LIKELY
GIVE TAF SITES A PERIOD OF LIGHT SNOW BETWEEN 12Z-17Z THIS
MORNING. HRRR FORECAST REFLECTIVITY SHOWS -SN MAINLY NORTHERN HALF
SC...HAVE INCLUDED A PERIOD OF -SN IN THE TAFS FOR A FEW HOURS
ALTHOUGH BULK OF PRECIP MAY BE NORTH. IFR CEILING AND VISIBILITIES
CONTINUE THIS MORNING WITH MVFR EXPECTED THIS AFTERNOON...BECOMING
VFR THURSDAY EVENING. NORTH WINDS 5-15 KNOTS BECOMING WESTERLY
AROUND 013/15Z.
EXTENDED AVIATION OUTLOOK...COLD FRONT FRIDAY NIGHT COULD BRING
MAINLY MVFR CONDITIONS...OTHERWISE LITTLE OR NO AVIATION
RESTRICTIONS ANTICIPATED ONCE CURRENT STORM MOVES AWAY FROM THE
REGION THURSDAY AFTERNOON.
&&
.CAE WATCHES/WARNINGS/ADVISORIES...
SC...WINTER STORM WARNING UNTIL NOON EST TODAY FOR SCZ015-016-018-
020>022-025>031-035>038-041.
GA...WINTER STORM WARNING UNTIL NOON EST TODAY FOR GAZ040-063>065-
077.
&&
$$
99
AREA FORECAST DISCUSSION
NWS COLUMBIA SC
411 AM EST THU FEB 13 2014
.SYNOPSIS...
LOW PRESSURE NEAR THE CAROLINA COAST WILL MOVE NORTHEASTWARD
TODAY. WINTRY PRECIPITATION WILL END FROM SOUTHWEST TO NORTHEAST.
A DRY WESTERLY FLOW NORTH OF A PRESSURE RIDGE IN THE GULF OF
MEXICO WILL DOMINATE TONIGHT AND FRIDAY. A COLD FRONT WILL MOVE
THROUGH THE FORECAST AREA FRIDAY NIGHT FOLLOWED BY HIGH PRESSURE
SATURDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
MUCH OF THE FREEZING RAIN ASSOCIATED WITH THE H85 JET HAS SHIFTED
NORTHEAST OF THE FORECAST AREA. AREAS OF FREEZING RAIN AND DRIZZLE
ARE OCCURRING IN IT WAKE. LITTLE ADDITIONAL ICE ACCUMULATION IS
EXPECTED. THE MID-LEVEL DRY SLOT SHOULD BE SHORT LIVED BASED ON
SATELLITE TRENDS EARLY THIS MORNING. THE MODELS SHOW MOISTURE
BECOMING DEEPER AS THE UPPER TROUGH SHIFTS EASTWARD THIS MORNING.
THIS WRAP-AROUND MOISTURE WILL LIKELY CAUSE AN INCREASE IN
PRECIPITATION...ESPECIALLY IN THE NORTH PART. BELIEVE THE SNOW
THAT WAS IN PARTS OF ALABAMA AND NORTH GEORGIA WILL MOVE INTO THE
FORECAST AREA. THE NAM TIME- HEIGHT DISPLAYS SHOW MOISTURE GETTING
INTO THE SNOW-GROWTH ZONE AS THE COLD UPPER TROUGH MOVES OVER THE
AREA. THE HRRR SHOWS H85 TEMPERATURES COOLING TO BELOW FREEZING
FROM WEST TO EAST DURING THE MORNING. USED THIS GUIDANCE FOR THE
TRANSITION TIME OF PRECIPITATION CHANGING TO SNOW. EXPECT MOST OF
THE AREA WILL HAVE A PERIOD OF SNOW WITH THE MORE SIGNIFICANT
ADDITIONAL AMOUNTS IN THE NORTH PART WITH MOISTURE WILL BE DEEPER.
AN AVERAGE OF THE NAM AND GFS QPF AND HPC GUIDANCE SUGGESTS SNOW
AMOUNTS OF 1 TO 2 INCHES IN THE NORTH PART...AND AN INCH OR LESS
ELSEWHERE.
THE LINGERING SNOW SHOULD END FROM SOUTH TO NORTH LATE THIS MORNING
AND EARLY THIS AFTERNOON. THE TEMPERATURE GUIDANCE APPEARS TOO
WARM BECAUSE OF THE ICE PACK. ALSO THE COLD UPPER TROUGH WILL BE
OVER THE FORECAST AREA FOR MUCH OF THE DAY.
A WINTER STORM WARNING REMAINS IN EFFECT THROUGH NOON.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM FRIDAY/...
A DRY WESTERLY FLOW NORTH OF THE GULF OF MEXICO PRESSURE RIDGE
WILL DOMINATE TONIGHT THROUGH FRIDAY. THE TEMPERATURE GUIDANCE IS
LIKELY TOO WARM BECAUSE OF THE DENSE ICE PACK.
&&
.LONG TERM /FRIDAY NIGHT THROUGH WEDNESDAY/...
A COLD FRONT WILL MOVE THROUGH THE FORECAST AREA FRIDAY NIGHT. THE
H85 WESTERLY FLOW SUGGESTED LITTLE MOISTURE WILL BE ASSOCIATED
WITH THIS FRONT. HOWEVER...THE ASSOCIATED MID-LEVEL SHORTWAVE
TROUGH WILL BE STRONG. AN AVERAGE OF THE NAM AND GFS MOS SUPPORT
POPS OF 30 TO 70 PERCENT WITH THE HIGHER VALUES IN THE NORTH PART
CLOSER TO THE STRONGER LIFT. MAINLY USED AN AVERAGE FOR THE POP
FORECAST EXCEPT DID NOT FORECAST QUITE LIKELY BECAUSE OF THE H85
WESTERLY FLOW. THERE MAY BE ENOUGH COOLING FOR A BRIEF MIX OF SNOW
IN THE NORTH PART. THE SYSTEM WILL BE PROGRESSIVE WITH MARGINAL
TEMPERATURES SO WE DO NOT EXPECT SIGNIFICANT SNOW.
THE GFS AND ECMWF SHOW DRY RIDGING DOMINATING DURING MOST OF THE
REMAINING MEDIUM-RANGE PERIOD. EXPECT LIMITED MOISTURE WITH A WEAK
FRONT MONDAY NIGHT OR TUESDAY. MODERATING TEMPERATURES SHOULD OCCUR.
THE GFS AND ECMWF MOS SUPPORT ABOVE NORMAL TEMPERATURES TUESDAY
AND WEDNESDAY.
&&
.AVIATION /09Z THURSDAY THROUGH MONDAY/...
LATEST RADAR RETURNS SHOW AREAS OF LIGHT TO MODERATE MAINLY FREEZING
RAIN MOVING ACROSS TAF SITES AT 13/06Z. IFR CEILING AND
VISIBILITIES CONTINUE OVERNIGHT WITH MVFR NOT EXPECTED UNTIL
THURSDAY AFTERNOON...BECOMING VFR THURSDAY EVENING. FREEZING RAIN WILL
DIMINISH IN INTENSITY AND GRADUALLY TAPER OFF TO MAINLY LIGHT
FREEZING DRIZZLE AND FOG AFTER 13/09Z BEFORE ENDING THURSDAY
MORNING. AS CURRENT SYSTEM MOVES AWAY FROM THE REGION BY THURSDAY
AFTERNOON...POSSIBLY SOME WRAP AROUND MAINLY LIGHT SNOW SOMETIME
BETWEEN 13/12Z AND 13/18Z MOVING QUICKLY ACROSS SC THURSDAY
MORNING. CONFIDENCE NOT HIGH ENOUGH TO PUT IN THE TAFS FOR NOW BUT
WILL MONITOR FOR DEVELOPMENT AND ADJUST IF NEEDED WITH THE 12Z
ISSUANCE. NORTH WINDS AROUND 10 KNOTS OVERNIGHT BECOMING WESTERLY
AROUND 013/15Z.
EXTENDED AVIATION OUTLOOK...COLD FRONT FRIDAY NIGHT COULD BRING
MAINLY MVFR CONDITIONS...OTHERWISE LITTLE OR NO AVIATION
RESTRICTIONS ANTICIPATED ONCE CURRENT STORM MOVES AWAY FROM THE
REGION THURSDAY AFTERNOON.
&&
.CAE WATCHES/WARNINGS/ADVISORIES...
SC...WINTER STORM WARNING UNTIL NOON EST TODAY FOR SCZ015-016-018-
020>022-025>031-035>038-041.
GA...WINTER STORM WARNING UNTIL NOON EST TODAY FOR GAZ040-063>065-
077.
&&
$$
AREA FORECAST DISCUSSION
NWS COLUMBIA SC
237 AM EST THU FEB 13 2014
.SYNOPSIS...
LOW PRESSURE NEAR THE CAROLINA COAST WILL MOVE NORTHEASTWARD
TODAY. WINTRY PRECIPITATION WILL END FROM SOUTHWEST TO NORTHEAST.
A DRY WESTERLY FLOW NORTH OF A PRESSURE RIDGE IN THE GULF OF
MEXICO WILL DOMINATE TONIGHT AND FRIDAY. A COLD FRONT WILL MOVE
THROUGH THE FORECAST AREA FRIDAY NIGHT FOLLOWED BY HIGH PRESSURE
SATURDAY.
&&
.NEAR TERM /THROUGH TODAY/...
MUCH OF THE FREEZING RAIN ASSOCIATED WITH THE H85 JET WILL SHIFT
NORTHEAST OF THE FORECAST AREA BY 400 AM. EXPECT MAINLY FREEZING
DRIZZLE WITH PATCHES OF LIGHT FREEZING RAIN IN ITS WAKE. LITTLE
ADDITIONAL ICE ACCUMULATION WILL OCCUR AFTER 400 AM. THE MID-LEVEL
DRY SLOT SHOULD BE SHORT LIVED BASED ON SATELLITE TRENDS EARLY
THIS MORNING. THE MODELS SHOW MOISTURE BECOMING DEEPER AS THE
UPPER TROUGH SHIFTS EASTWARD THIS MORNING. THIS WRAP-AROUND
MOISTURE WILL LIKELY CAUSE AN INCREASE IN PRECIPITATION...ESPECIALLY
IN THE NORTH PART. BELIEVE THE SNOW THAT WAS IN PARTS OF ALABAMA
AND NORTH GEORGIA WILL MOVE INTO THE FORECAST AREA. THE NAM TIME-
HEIGHT DISPLAYS SHOW MOISTURE GETTING INTO THE SNOW-GROWTH ZONE
AS THE COLD UPPER TROUGH MOVES OVER THE AREA. THE HRRR SHOWS H85
TEMPERATURES COOLING TO BELOW FREEZING FROM WEST TO EAST DURING
THE MORNING. USED THIS GUIDANCE FOR THE TRANSITION TIME OF
PRECIPITATION CHANGING TO SNOW. EXPECT MOST OF THE AREA WILL HAVE
A PERIOD OF SNOW WITH THE MORE SIGNIFICANT ADDITIONAL AMOUNTS IN
THE NORTH PART WITH MOISTURE WILL BE DEEPER. AN AVERAGE OF THE NAM AND
GFS QPF AND HPC GUIDANCE SUGGESTS SNOW AMOUNTS OF 1 TO 2 INCHES IN
THE NORTH PART...AND AN INCH OR LESS ELSEWHERE.
THE LINGERING SNOW SHOULD END FROM SOUTH TO NORTH LATE THIS MORNING
AND EARLY THIS AFTERNOON. THE TEMPERATURE GUIDANCE APPEARS TOO
WARM BECAUSE OF THE ICE PACK. ALSO THE COLD UPPER TROUGH WILL BE
OVER THE FORECAST AREA FOR MUCH OF THE DAY.
A WINTER STORM WARNING REMAINS IN EFFECT THROUGH NOON.
&&
.SHORT TERM /TONIGHT THROUGH FRIDAY/...
A DRY WESTERLY FLOW NORTH OF THE GULF OF MEXICO PRESSURE RIDGE
WILL DOMINATE TONIGHT THROUGH FRIDAY. THE TEMPERATURE GUIDANCE IS
LIKELY TOO WARM BECAUSE OF THE DENSE ICE PACK.
&&
.LONG TERM /FRIDAY NIGHT THROUGH WEDNESDAY/...
A COLD FRONT WILL MOVE THROUGH THE FORECAST AREA FRIDAY NIGHT. THE
H85 WESTERLY FLOW SUGGESTED LITTLE MOISTURE WILL BE ASSOCIATED
WITH THIS FRONT. HOWEVER...THE ASSOCIATED MID-LEVEL SHORTWAVE
TROUGH WILL BE STRONG. AN AVERAGE OF THE NAM AND GFS MOS SUPPORT
POPS OF 30 TO 70 PERCENT WITH THE HIGHER VALUES IN THE NORTH PART
CLOSER TO THE STRONGER LIFT. MAINLY USED AN AVERAGE FOR THE POP
FORECAST EXCEPT DID NOT FORECAST QUITE LIKELY BECAUSE OF THE H85
WESTERLY FLOW. THERE MAY BE ENOUGH COOLING FOR A BRIEF MIX OF SNOW
IN THE NORTH PART. THE SYSTEM WILL BE PROGRESSIVE WITH MARGINAL
TEMPERATURES SO WE DO NOT EXPECT SIGNIFICANT SNOW.
THE GFS AND ECMWF SHOW DRY RIDGING DOMINATING DURING MOST OF THE
REMAINING MEDIUM-RANGE PERIOD. EXPECT LIMITED MOISTURE WITH A WEAK
FRONT MONDAY NIGHT OR TUESDAY. MODERATING TEMPERATURES SHOULD OCCUR.
THE GFS AND ECMWF MOS SUPPORT ABOVE NORMAL TEMPERATURES TUESDAY
AND WEDNESDAY.
&&
.AVIATION /07Z THURSDAY THROUGH MONDAY/...
LATEST RADAR RETURNS SHOW AREAS OF LIGHT TO MODERATE MAINLY FREEZING
RAIN MOVING ACROSS TAF SITES AT 13/06Z. IFR CEILING AND
VISIBILITIES CONTINUE OVERNIGHT WITH MVFR NOT EXPECTED UNTIL
THURSDAY AFTERNOON...BECOMING VFR THURSDAY EVENING. FREEZING RAIN WILL
DIMINISH IN INTENSITY AND GRADUALLY TAPER OFF TO MAINLY LIGHT
FREEZING DRIZZLE AND FOG AFTER 13/09Z BEFORE ENDING THURSDAY
MORNING. AS CURRENT SYSTEM MOVES AWAY FROM THE REGION BY THURSDAY
AFTERNOON...POSSIBLY SOME WRAP AROUND MAINLY LIGHT SNOW SOMETIME
BETWEEN 13/12Z AND 13/18Z MOVING QUICKLY ACROSS SC THURSDAY
MORNING. CONFIDENCE NOT HIGH ENOUGH TO PUT IN THE TAFS FOR NOW BUT
WILL MONITOR FOR DEVELOPMENT AND ADJUST IF NEEDED WITH THE 12Z
ISSUANCE. NORTH WINDS AROUND 10 KNOTS OVERNIGHT BECOMING WESTERLY
AROUND 013/15Z.
EXTENDED AVIATION OUTLOOK...COLD FRONT FRIDAY NIGHT COULD BRING
MAINLY MVFR CONDITIONS...OTHERWISE LITTLE OR NO AVIATION
RESTRICTIONS ANTICIPATED ONCE CURRENT STORM MOVES AWAY FROM THE
REGION THURSDAY AFTERNOON.
&&
.CAE WATCHES/WARNINGS/ADVISORIES...
SC...WINTER STORM WARNING UNTIL NOON EST TODAY FOR SCZ015-016-018-
020>022-025>031-035>038-041.
GA...WINTER STORM WARNING UNTIL NOON EST TODAY FOR GAZ040-063>065-
077.
&&
$$
AREA FORECAST DISCUSSION
NWS PEACHTREE CITY GA
1250 AM EST THU FEB 13 2014
.PREV DISCUSSION... /ISSUED 901 PM EST WED FEB 12 2014/
UPDATE...
SURFACE LOW PRESSURE JUST OFFSHORE THE PANHANDLE OF FLORIDA THIS
EVENING. REGIONAL RADAR SHOWS SOME HEAVIER PRECIP BEGINNING TO
FILL BACK IN ACROSS MUCH OF CENTRAL GA THIS EVENING...THE PRECIP
MAINLY SOUTH OF THE ATL METRO LOOKS CONVECTIVE IN NATURE...SO
EXPECT LOCALLY HEAVY FZRA IN AREAS WHERE TEMPS AOB 32 DEGREES.
NORTH OF THE METRO AREA...WHERE THE PRECIP RETURNS LOOK MORE
UNIFORM...HEAVY SNOW BANDS HAVE SET UP ACROSS NW GA IN THE
VICINITY OF THE STRONG MID LEVEL FORCING.
THE BACK EDGE OF THE PRECIP IS NOTED ACROSS WEST CENTRAL AL. STILL
EXPECT THOSE AREAS RECEIVING A WINTRY MIX TO FINISH UP AS
SNOW/SLEET OR ALL SNOW. THE SNOW COULD BE LOCALLY HEAVY BEFORE
TAPERING OFF.
MADE SOME EARLIER TWEAKS THE WEATHER GRIDS. MAY HAVE TO MAKE SOME
CHANGES TO THE HOURLY TEMP/DEWPOINT GRIDS LATER ON...BUT THEY LOOK
TO BE ON TRACK NOW. ALSO MADE SOME TWEAKS TO THE ADDITIONAL STORM
TOTAL SNOW/ICE GRIDS FOR THE WEB GRAPHICS.
NO CHANGES TO THE HEADLINES.
PREV DISCUSSION... /ISSUED 637 PM EST WED FEB 12 2014/
PREV DISCUSSION... /ISSUED 451 PM EST WED FEB 12 2014/
SIGNIFICANT WINTER STORM CONTINUES...
SHORT TERM /TONIGHT THROUGH THURSDAY/...
MAIN CONCERN CONTINUES TO BE WITH ONGOING MIXTURE OF SNOW...
SLEET...AND FREEZING RAIN ACROSS THE CWA AND IMPACTS ON ALREADY
WIDESPREAD POWER OUTAGES...TREES/LIMBS DOWN...AND ROAD CONDITIONS.
CLASSICAL CAD WEDGE MAINTAINS CAA FROM THE STRONG 1032MB PARENT HIGH
MOVING OFF THE NEW ENGLAND COAST. THIS HAS BEEN FIGHTING DIABATIC
EFFECTS FROM THE OVERRUNNING GULF MOISTURE AND FLUCTUATING BETWEEN
SLEET AND FREEZING RAIN ACROSS PORTIONS OF CENTRAL GA.
WHILE PREVIOUS UPSTREAM SLUG OF MOISTURE NEAR THE NORTHERN GULF MAY
HAVE LIMITED PREVIOUS DAYTIME QPF...THE HRRR VERIFIED WELL DURING
THIS TIME AND WAS CONSISTENT WITH SOME DEVELOPMENT FILLING BACK IN
LATE AFTERNOON INTO EVENING BEFORE THE EXITING OF THE SYSTEM. THIS
IS SUPPORTED BY GOOD ISENTROPIC FORCING AGAINST THE WEDGE AND UPPER
FORCING FROM GOOD DIVERGENCE ALOFT AND INCREASING PVA WITH THE
AMPLIFYING TROUGH STILL WEST OF THE REGION. HAVE TRENDED POPS CLOSE
TO THIS SOLUTION UNTIL NEAR 06Z THEN CLOSE TO BLEND OF GENERAL
GUIDANCE AS THE WRAP-AROUND MOISTURE WITH THE BAROCLINIC LEAF OF THE
DEEPENING LOW IMPACTS MAINLY THE NORTHERN TWO THIRDS OF THE CWA
OVERNIGHT.
THERMAL PROFILES AND TRENDS ACROSS THE AREA HAS SUPPORTED A SMALLER
SWATH OF SIGNIFICANT FREEZING RAIN...WHICH COULD EASILY BE MIXED WITH
SLEET AT TIMES. THE NORTHEASTERN TIER OF THE PREVIOUS ICE STORM
WARNING LOOKS TO PRIMARILY GET A SLEET AND SNOW MIX SO HAVE
TRANSITIONED THE COUNTIES NORTH OF I-20 INTO THE WINTER STORM
WARNING AND OUT OF THE ICE STORM ZONE. THE REST OF THE NORTH HAS
RECENTLY HAD A MIXTURE OF MAINLY SLEET AND SNOW WITH SOME MORE
CONVECTIVE LOOKING BANDS...HOWEVER THIS SHOULD TRANSITION OVER TO
ALL SNOW THIS EVENING AS THE DEFORMATION ZONE SETS UP WITH THE LOW
SWINGING THROUGH. THE GFS APPEARS TO HAVE A MORE APPARENT 700MB
TROWAL ACROSS EASTERN PORTIONS OF THE AREA NEAR 06Z. THIS WILL HAVE
TO BE MONITORED AS TO HOW FAR SOUTH SOME SNOW BANDING MAY REACH AND
COULD DROP A QUICK 1-2 INCHES FARTHER SOUTH INTO PORTIONS OF CENTRAL
GA.
FOR ICE AND SNOW AMOUNTS...HAVE TONED ICE AMOUNTS DOWN TO AN
ADDITIONAL QUARTER OR UP TO THIRD OF AN INCH IN THE WARNING AREA AND
HAVE GONE WITH SIMILAR ADVERTISED SNOW AMOUNTS BEING MAXIMIZED IN
THE NORTHEAST OF AN ADDITIONAL 4-8 INCHES...AND 1-3 INCHES IN A SW
TO NE SWATH FROM A LAGRANGE TO ATLANTA TO ATHENS ZONE.. THIS HAS THE
POTENTIAL TO BE UNDERCUT BY SOME SLEET AT TIMES.
FOR TEMPS...HAVE BEEN DIFFICULT TO PINPOINT TRENDS WITH EVENT BUT
HAVE HAD LOCAL RISES AND FALLS BY 1-2 DEGREES. SHOULD STILL REACH
OVERNIGHT LOWS OF 2-3 DEGREES BELOW FREEZING FOR MOST AREAS SO WILL
POSE A MAJOR THREAT OF THE AFOREMENTIONED MIXED PRECIP FREEZING
TOGETHER. ANY MELTING THAT OCCURS THURSDAY AFTERNOON WITH MANY AREAS
PROGGED TO REACH THE LOW 40S WILL ALSO POSE A DANGER FOR FALLING
PIECES OF ICE.
GRADIENT WINDS SHOULD STILL BE ENHANCED THROUGH THIS EVENING DUE TO
THE STRENGTHENING LOW AND LINGERING HIGH...WHICH WILL CONTINUE TO
CAUSE LIMBS AND TREES TO FALL ALONG WITH ADDITIONAL POWER OUTAGES
LIKELY.
ALL-IN-ALL THE PRIMARY THREATS OF THE WINTER STORM AND ICE CONTINUE
BUT ACROSS SLIGHTLY DIFFERENT ZONES...EVEN THOUGH SOME ICE AMOUNTS
HAVE BEEN ADJUSTED LOWER. THERE IS STILL A GREAT DEAL OF CONCERN
WITH THIS SYSTEM SO PLEASE STAY PUT AND REMAIN OFF THE ROADS AND IN
A SAFE LOCATION!
BAKER
LONG TERM /THURSDAY NIGHT THROUGH WEDNESDAY/...
NO CHANGES TO THE FORECAST GRIDS PAST THURSDAY RIGHT NOW. FAST
MOVING SYSTEM STILL EXPECTED TO SWEEP THROUGH LATE IN THE DAY
THROUGH THE EVENING FRIDAY. WILL LIKELY SEE SHOWERS MOVING INTO THE
NORTH IN THE AFTERNOON WITH SOME MIXING OF SNOW AS IT MOVES ACROSS
THE NORTH IN THE EVENING. MOISTURE IS LIMITED AND SURFACE
TEMPERATURES ARE EXPECTED REMAIN AT OR ABOVE FREEZING FOR ALL BUT
THE FAR NORTH THROUGH THE DURATION OF THIS PRECIPITATION SO LITTLE
OR NO ACCUMULATIONS ARE EXPECTED MOST AREAS. WILL NEED TO KEEP AN
EYE ON THE TRENDS AS WE GET CLOSER FOR CHANGES IN EXPECTED IMPACTS.
ONE FLY IN THE OINTMENT MAY BE AREAS IN THE FAR NORTH THAT STILL
HAVE ICE/SNOW LINGERING FROM THE CURRENT STORM.
20
LONG TERM /THURSDAY NIGHT THROUGH TUESDAY/...
/ISSUED AT 339 AM EST WED FEB 12 2014/
NEXT CONCERN WILL BE A FAST MOVING COLD FRONT AND ASSOCIATED UPPER
TROUGH FORECAST TO MOVE ACROSS THE AREA FRIDAY AFTERNOON AND NIGHT.
ASSOCIATE MOISTURE BRINGS PRECIP CHANCES MAINLY INTO N GA FRIDAY
AFTERNOON AND ACROSS THE AREA FRIDAY NIGHT. TEMPERATURES APPEAR COLD
ENOUGH FOR A RAIN SNOW MIX OR A CHANGE OVER TO SNOW FRIDAY EVENING
FOR PORTIONS OF N GA WITH A DUSTING POSSIBLE FOR FAR N FULTON COUNTY
AND NE TO THE MOUNTAINS.
MODELS RATHER INCONSISTENT BRINGING MOISTURE ACROSS N GA SATURDAY
NIGHT ASSOCIATED WITH A WEAK UPPER TROUGH. TEMPERATURES COLD ENOUGH
FOR LIGHT RAIN OR SNOW WITH NO SIGNIFICANT ACCUMULATIONS EXPECTED AT
THIS TIME.
GFS AND EUROPEAN DIFFERING WITH A COLD FRONT EARLY NEXT WEEK. GFS
MUCH FASTER BRINGING A COLD FRONT ACROSS THE AREA MONDAY NIGHT AND
TUESDAY AND THE EUROPEAN BRINGING THE FRONT ACROSS THE AREA TUESDAY
AFTERNOON AND NIGHT. AT THIS TIME FAVORING THE WPC POP GRID FOR
MONDAY NIGHT WITH CHANCE POPS ACROSS NORTH AND PORTIONS OF CENTRAL
GA. THIS COULD CHANGE GREATLY WITH OTHER MODEL RUNS. AT THIS TIME
AIRMASS SEEMS TO SUPPORT LIGHT RAIN OR LIGHT SHOWERS ONLY.
BDL
&&
.AVIATION...
06Z UPDATE...
PATCHES OF WINTRY MIX MOVING ACROSS TAF SITES...WITH AREA OF -SN
EXPECTED TO MOVE ACROSS NORTH TAF SITES THRU 10Z. ANTICIPATE
WINTER PRECIP TO WIND DOWN BY 10-12Z. IFR/VFR CONDS WILL DROP TO
IFR/LIFR AS -SN MOVES ACROSS...BUT AS PRECIP MOVES OUT WE SHOULD
START TO SEE CLEARING FROM WEST TO EAST. WINDS INITIALLY OUT OF
NORTHWEST IS STARTING TO BACK OUT OF THE NORTHWEST OVER NORTHWEST
GA AND SHOULD BE NW TO N BY 10Z. WIND SPEEDS WILL INCREASE WITH
GUSTS TO 20KTS POSSIBLE...ESPECIALLY ATL AREA AND AHN TAF SITES.
//ATL CONFIDENCE...06Z UPDATE...
MED-HIGH CONFIDENCE ALL ELEMENTS.
ATWELL
&&
.PRELIMINARY POINT TEMPS/POPS...
ATHENS 42 31 49 29 / 30 0 20 30
ATLANTA 43 34 52 31 / 20 0 20 30
BLAIRSVILLE 40 25 45 24 / 30 5 60 40
CARTERSVILLE 43 30 51 28 / 20 0 30 30
COLUMBUS 48 36 59 35 / 10 0 10 20
GAINESVILLE 43 32 49 29 / 30 0 20 30
MACON 46 32 57 35 / 20 0 10 20
ROME 43 29 50 28 / 20 5 60 30
PEACHTREE CITY 44 30 54 30 / 20 0 20 30
VIDALIA 47 35 61 40 / 20 0 5 20
&&
.FFC WATCHES/WARNINGS/ADVISORIES...
ICE STORM WARNING UNTIL 1 PM EST THIS AFTERNOON FOR THE
FOLLOWING ZONES: BALDWIN...BIBB...BLECKLEY...BUTTS...CARROLL...
CLAYTON...COWETA...CRAWFORD...DOUGLAS...EMANUEL...FAYETTE...
GLASCOCK...GREENE...HANCOCK...HEARD...HENRY...HOUSTON...JASPER...
JEFFERSON...JOHNSON...JONES...LAMAR...LAURENS...MERIWETHER...
MONROE...MORGAN...NEWTON...PEACH...PIKE...PUTNAM...ROCKDALE...
SOUTH FULTON...SPALDING...TALIAFERRO...TREUTLEN...TROUP...
TWIGGS...UPSON...WARREN...WASHINGTON...WILKINSON.
FREEZING RAIN ADVISORY UNTIL 1 PM EST THIS AFTERNOON FOR THE
FOLLOWING ZONES: CHATTAHOOCHEE...CRISP...DODGE...DOOLY...
HARRIS...MACON...MARION...MONTGOMERY...MUSCOGEE...PULASKI...
SCHLEY...STEWART...SUMTER...TALBOT...TAYLOR...TELFAIR...TOOMBS...
WEBSTER...WHEELER...WILCOX.
WINTER STORM WARNING UNTIL 1 PM EST THIS AFTERNOON FOR THE
FOLLOWING ZONES: BANKS...BARROW...BARTOW...CATOOSA...CHATTOOGA...
CHEROKEE...CLARKE...COBB...DADE...DAWSON...DEKALB...FANNIN...
FLOYD...FORSYTH...GILMER...GORDON...GWINNETT...HALL...HARALSON...
JACKSON...LUMPKIN...MADISON...MURRAY...NORTH FULTON...OCONEE...
OGLETHORPE...PAULDING...PICKENS...POLK...TOWNS...UNION...
WALKER...WALTON...WHITE...WHITFIELD...WILKES.
&&
$$
SHORT TERM...ATWELL
LONG TERM....17
AVIATION...ATWELL
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
319 PM CST THU FEB 13 2014
.DISCUSSION...
318 PM CST
SHORT TERM...TONIGHT THROUGH SUNDAY...
PRIMARY FORECAST CONCERNS ARE WITH MINOR TO MODERATE SNOW EVENT ON
SATURDAY. A FAST MOVING SYSTEM LOOKS TO POSSIBLY CLIP THE FAR
SOUTHERN CWA ON FRIDAY...FOLLOWED BY THE POTENTIAL FOR ONE MORE
FAIRLY WIDESPREAD SUBZERO NIGHT FRIDAY NIGHT BEFORE NEXT WEEK`S
BIG PATTERN CHANGE.
TONIGHT...
COLD FRONT TRAILING FROM CLIPPER SYSTEM THAT BROUGHT WIDESPREAD SNOW
SHOWERS TODAY IS BACK ACROSS CENTRAL AND WESTERN IA AND IT WILL
TRACK ACROSS THE AREA THIS EVENING...WITH WINDS TURNING WESTERLY AND
USHERING IN COLD ADVECTION. SOME GUIDANCE INDICATES POTENTIAL FOR
FLURRIES OR DRIZZLE AS LAPSE RATES STEEPEN BEHIND THE FRONT...BUT
HAVE NOT INDICATED IN FORECAST. MODEL SOUNDINGS INDICATE VERY
SHALLOW MOISTURE SO ITS DOUBTFUL THERE WILL BE ANY PRECIP BUT WILL
MONITOR THIS. THERE SHOULD BE A GOOD DEAL OF CLOUD COVER FOR MOST OF
THE NIGHT...BUT NONETHELESS CAA SHOULD ENABLE LOWS TO DIP TO THE
HIGH SINGLE DIGITS AND TEENS BY DAYBREAK FRIDAY...MILDEST IN
SOUTHEAST. CONFIDENCE IN LOW TEMPERATURES IS MEDIUM.
FRIDAY AND FRIDAY NIGHT...
SHORTWAVE ENERGY IN FAST FLOW INTO PAC NW WILL QUICKLY DROP
SOUTHEAST INTO CENTRAL PLAINS TONIGHT...INITIATING LOW PRESSURE
DEVELOPMENT. GUIDANCE IS IN GOOD AGREEMENT IN TRACKING SYSTEM ALONG
OR SOUTH OF OH RIVER BY MID-DAY FRIDAY. PATH OF SURFACE LOW AND
UPPER LEVEL FORCING INDICATES THAT ONLY SOUTHERN CWA MAY SEE
GLANCING BLOW OF SNOWFALL TOMORROW...WHERE CHANCE POPS WERE
MAINTAINED. RADAR TRENDS WILL NEED TO BE WATCHED TOMORROW AS TO HOW
FAR NORTH THE SNOW SHIELD EXTENDS. THE POTENTIAL FOR DECENT
ACCUMULATIONS WILL NOT BE ALL FAR SOUTH OF OUR FAR SOUTHERN
COUNTIES...BUT GIVEN STRONG MODEL CONSENSUS IT APPEARS THAT AT MOST
A DUSTING TO A HALF INCH OR SO WOULD OCCUR IN THE FAR SOUTH. AS
SYSTEM DEPARTS SOUTHEAST LATER TOMORROW...CLOUD COVER WILL BEGIN TO
ERODE FROM NORTHWEST. 850/925 MB CLIMATOLOGY SUPPORTS HIGH
TEMPERATURES IN THE LOWER AND MID 20S.
SKIES ARE ANTICIPATED TO BECOME MAINLY CLEAR TO PC MUCH OF FRIDAY
NIGHT BEFORE CLOUDS ARRIVE FROM NORTHWEST IN ADVANCE OF NEXT
CLIPPER. HIGH PRESSURE RIDGE WILL BE CENTERED A BIT SOUTH OF THE
CWA...BUT VERY WEAK PRESSURE GRADIENT WILL ENABLE NORTHWEST WINDS TO
BECOME LIGHT OR CALM OVERNIGHT. ASSUMING CLOUDS DO NOT OVERSPREAD
AREA EARLIER...DECOUPLED BOUNDARY LAYER AND DEEP SNOWPACK WILL
LIKELY RESULT IN SUBZERO LOWS FOR MOST LOCATIONS OUTSIDE OF THE
IMMEDIATE CHICAGO AREA. GIVEN HOW EASILY FAVORED COLD SPOTS HAVE
PLUMMETED IN RECENT NIGHTS WITH GOOD RADIATIONAL COOLING
CONDITIONS...STILL CONSIDERED THAT LOW-MID MINUS SINGLE DIGITS MAY
NOT BE COLD ENOUGH IN SOME AREAS.
SATURDAY THROUGH SATURDAY EVENING...
GUIDANCE IS OVERALL IN GOOD AGREEMENT IN TRACKING CLIPPER JUST SOUTH
OF CWA ON SATURDAY AND THE TIMING OF THE SYSTEM...THOUGH THERE ARE
SOME DIFFERENCES IN HOW ROBUST FORCING REMAINS INTO THE EVENING
HOURS. EVEN THE GUIDANCE THAT MAINTAINS STRONGER FORCING WITH UPPER
WAVE MOVING ACROSS REGION DOES INDICATE AN OVERALL
DAMPENING/WEAKENING TREND...SO BEST SNOWFALL RATES SHOULD BE FOCUSED
INTO WESTERN HALF OF CWA AS MENTIONED ON PREVIOUS DISCUSSIONS.
NONETHELESS..CONFIDENCE CONTINUES TO GROW IN ENTIRE CWA SEEING
ACCUMULATING SNOW OUT OF THIS SYSTEM. MODEL SOUNDINGS SHOW A SEVERAL
HOUR PERIOD OF FAVORABLE LIFT AND SATURATION THROUGH A RELATIVELY
DEEP DGZ...AND WITH TEMPERATURES IN LOWER 20S...RATIOS SHOULD BE A
BIT ABOVE AVERAGE AT AROUND 15:1. SIMILAR GENERAL IDEA OF A 1 TO 3
INCH SNOWFALL WITH THIS FORECAST PACKAGE...HIGHEST AGAIN LIKELY
FOCUSED INTO WESTERN HALF OF CWA. ACCUMULATING SNOW SHOULD START BY
EARLY AFTERNOON IN NORTHWEST CWA OVERSPREADING REST OF AREA BY EARLY
EVENING. WILL NEED TO WATCH FOR EARLIER ONSET AS SOMETIMES OCCURS
WITH CLIPPER SYSTEMS...AS WELL AS SOME LINGERING SNOWS IN THE
SOUTHEAST HALF AFTER MIDNIGHT.
SUNDAY...
SURFACE HIGH OVER THE REGION WILL SUPPORT QUIET WEATHER
CONDITIONS...THOUGH RAPID WARM ADVECTION ALOFT SHOULD RESULT IN
INCREASING AFTERNOON CLOUDS. HIGHS WILL BE IN THE MID AND UPPER
20S...STILL BELOW NORMAL BUT OTHERWISE FAIRLY PLEASANT IN THIS
BITTERLY COLD WINTER.
RC
*LONG TERM DISCUSSION TO BE ISSUED SHORTLY.
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 20Z...
* SOUTH WINDS GUSTING TO 20 KT BECMG WEST THIS EVENING WITH A FEW
GUSTS UP TO 25 KT FROM MID AFTERNOON ONWARD.
* MVFR CIGS TONIGHT AND POSSIBLE AGAIN FRIDAY AFTERNOON.
ZEBIC
//DISCUSSION...UPDATED 18Z...
NORTH-SOUTH BAND OF LIGHT SNOW AHEAD OF WARM FRONT TO MOVE OUT OF
THE TERMINAL AREA WITHIN THE NEXT FEW HOURS. WARM FRONT CROSSING MS
RIVER WILL BRING WIND MORE SOUTHWEST WITH MID AFTERNOON PASSAGE
AND A BRIEF SPELL OF WARMER TEMPERATURES.
ASSOCIATED LOW PRESSURE TO TRACK EAST ACROSS THE FAR NORTHERN
STRETCH OF THE REGION THIS AFTERNOON AND TONIGHT. TRAILING COLD
FRONT TO SWEEP ACROSS THE TERMINALS THIS EVENING. COLD AIR TO FILL
IN SLOWLY BEHIND FRONT AND ACROSS SNOW PACK LEADING CIGS TO LIKELY
FALL INTO THE MVFR RANGE INTO THE OVERNIGHT THEN COULD REDEVELOP WITH
DAYTIME HEATING TOMORROW.
FREEZING DRIZZLE CHANCES THIS EVENING REMAIN MINIMAL AND IF DOES
OCCUR WOULD LIKELY BE A NUISANCE AT WORSE.
ZEBIC
//ORD AND MDW CONFIDENCE...UPDATED 20Z...
* MEDIUM CONFIDENCE IN CIGS FCST.
* HIGH CONFIDENCE IN ALL OTHER FORECAST ELEMENTS.
ZEBIC
//OUTLOOK FOR ORD/MDW FOR 00Z SATURDAY-12Z THURSDAY...UPDATED 12Z...
FRIDAY NIGHT...VFR.
SATURDAY...SNOW IN THE AFTN AND EVENING...IFR LIKELY.
SUNDAY...CHC OF FREEZING RAIN OR ICE PELLETS OVERNIGHT. VFR BCMG
MVFR OR LOWER OVERNIGHT.
MONDAY...RAIN OR FREEZING RAIN IN THE MORNING BCMG RAIN OR SNOW IN
THE AFTN. DRY OVERNIGHT. IFR IMPROVING VFR OVERNIGHT.
TUESDAY...VFR.
WEDNESDAY...CHC OF RAIN. VFR BCMG MVFR OR LOWER.
JEE
&&
.MARINE...
242 PM CST
SURFACE RIDGE HAS PUSHED EAST OF THE REGION...WITH AN AREA OF LOW
PRESSURE SLIDING SOUTHEAST ACROSS THE UPPER MIDWEST TOWARDS THE
GREAT LAKES TONIGHT. THIS LOW SHOULD SLIDE EAST ACROSS NORTHERN
LAKE MICHIGAN...WITH AN INCREASING GRADIENT THROUGHOUT THE EVENING
AND OVERNIGHT HOURS. EXPECT THIS WILL GENERATE GUSTS TO 30
KT...AND BUILD WAVES SLIGHTLY. DUE TO THE EXTENSIVE ICE
COVERAGE...WAVES WILL LIKELY NOT BE ABLE TO BUILD AS LARGE AS WITH
OPEN WATERS. NONETHELESS...WAVES IN ICE FREE AREAS SHOULD BE ABLE
TO BUILD TO AROUND 4 TO 6 FT. THEN A RIDGE OF HIGH PRESSURE WILL
PUSH ACROSS THE LAKES SATURDAY...WITH LIGHTER WINDS. THE NEXT LOW
PASSES WELL SOUTH OF THE LAKE AND REACHES THE WESTERN OHIO VALLEY
SATURDAY NIGHT. WINDS REMAIN LIGHT WITH DIRECTIONS VARYING FROM
EAST TO NORTHEAST.
HIGH PRESSURE THEN SPREADS OVER THE LAKE SUNDAY. WINDS TURN
SOUTHEAST AND INCREASE IN SPEED AHEAD OF THE NEXT LOW SUNDAY
NIGHT. BY MONDAY MORNING WINDS WILL SE TO S TO 30 KT AND THEN VEER
TO WEST 10-20 KT MONDAY NIGHT BEHIND THE LOW. THE REMAINDER OF
EARLY NEXT WEEK LOOKS QUIET OVER THE LAKE.
BEACHLER
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...SMALL CRAFT ADVISORY...ILLINOIS NEARSHORE WATERS UNTIL 9 AM FRIDAY.
&&
$$
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Area Forecast Discussion
National Weather Service Lincoln IL
311 PM CST Thu Feb 13 2014
.DISCUSSION...
ISSUED 311 PM CST Thu Feb 13 2014
Models look in fairly good agreement with the next two waves
coming through the area through the weekend. So, a blend of the
models looks like a good forecast at this time, in the short term.
In the extended, one system moves into the area for first part of
the week. With temps warming, pcpn type will be tricky at onset of
the pcpn. Then looks like another system is forecast for later
part of the week. Models show some differences on timing of this
system, but all models forecasting warmer temps for next week.
SHORT TERM...Tonight through Sunday
Another snow event is coming for very late tonight through
tomorrow. All models are in good agreement with this system so
confidence is high with timing, location and amounts for this
event. Models have trended little further north with best area of
lift and moisture. Looks like snow will begin in the extreme west
after 09z tonight and then overspread the rest of central and
southeast Illinois by 15z. Heaviest snow band should setup south
of a Macomb to Lincoln to Paris line. With the sfc low tracking
from southern MO to western TN tomorrow, looks like should be
plenty of moisture for there to be enough accumulating snow to
reach advisory criteria by tomorrow afternoon. Does look like most
of snow will be tomorrow morning from 6am to noon, with lingering
snow still occurring in the east and southeast during the early
afternoon. So a winter weather advisory will be issued for already
mentioned areas. Snowfall amounts will decrease rapidly to the
north. After a brief dry period, Friday night, another minor snow
event will track across the north into the Grt Lks region. Highest
snowfall amounts, near an inch, will be in the extreme north of
the cwa with axis being along and north of I-74. This snow will
occur mainly Sat afternoon and Sat evening. Then dry weather
should return of Sunday.
Temps through the period will remain cold, below normal.
LONG TERM...Sunday night through Thursday
Extended period is forecasting a change in the pattern, though it
may be temporary. However, another system is forecast to move into
the region beginning Sunday night and continuing into Monday. This
system will have to overcome a lot of dry air initially so the
pcpn could begin as a mix of sleet and freezing rain. The temps
will warm up to above freezing early Monday morning, so pcpn will
change over to all rain. Pcpn will begin northwest of the IL river
Sunday night, before overspreading the rest of the area as just
rain on Monday. Pcpn could end as a mix of rain and snow, but this
is not worth mentioning at this time. The next weather system will
be Wed through Thur and based on the warmer temps, this pcpn will
be all rain. Cloudy, windy and foggy conditions are also possible as
there will have been several days of temps above freezing and we
have a lot of snow to melt over most of the area. Initial looks at
this system show that thunderstorms are possible, but with models
disagreeing and system 7 days out, it is too soon add
thunderstorms at this time.
Definite warming trend in store for next week. Daytime temps will
warm to above freezing, however, overnight lows will still fall
back to below freezing over portions of the area Mon night and Tue
night. Lows Wed night will be above freezing.
Auten
&&
.AVIATION...
ISSUED 1150 AM CST Thu Feb 13 2014
Several aviation concerns of note for the 18z TAFs. Band of
mid-level cloudiness currently in place over central Illinois
will quickly shift off to the east over the next couple of hours,
leaving behind mostly clear skies late this afternoon. First big
question is whether MVFR ceilings over Minnesota/northern Iowa
will rotate far enough southeast to impact any of the terminals
this evening. Satellite loops suggest most of this cloud cover will
remain to the north: however, HRRR has been consistently showing
clouds developing/spreading into north-central Illinois during the
evening. Will therefore include a 4-hour period of MVFR ceilings
at all sites except KSPI between 00z and 06z. Once these clouds
depart, only mid/high clouds will prevail through the night. Next
issues will be approach of clipper system and the timing of lower
ceilings and snow. 12z NAM/GFS fairly similar in aggressively
spreading snow across the area early Friday morning, with the
heaviest/steadiest snow focused south of the I-74 corridor. Based
on NAM forecast soundings, have introduced snow at KSPI as early
as 12z, then further northeast to KCMI by 15z. Will carry MVFR
ceilings at the I-74 terminals, but will go with lower IFR
ceilings at both KSPI and KDEC within the heavier snow band Friday
morning.
Barnes
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
WINTER WEATHER ADVISORY from Midnight tonight to 6 PM CST Friday
FOR ILZ040-047>057-061>063-066>068-071>073.
&&
$$
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
1238 PM CST THU FEB 13 2014
.MESOSCALE DISCUSSION...
1122 AM CST
LATEST SPC MESOANALYSIS INDICATES VERY STEEP MIDLEVEL LAPSE RATES
OF 7-8C/KM ACROSS NORTHERN ILLINOIS IN PLACE WITH ADVANCING WARM
FRONT TRAILING FROM CLIPPER NORTH OF MSP. COMBINED WITH MIDLEVEL
SPEED MAX PUNCHING INTO AREA NOTED ON W/V IMAGERY...THIS HAS
RESULTED IN BROKEN BAND OF SNOW SHOWERS PUSHING EAST. GIVEN THE
STEEP MIDLEVEL LAPSE RATES...BRIEF MODERATE TO HEAVY SNOW RATES
ARE OCCURRING IN THE SNOW SHOWERS...MOST PROMINENTLY ACROSS FAR
NORTHERN ILLINOIS AND IN ANOTHER BAND ADVANCING EASTWARD CURRENTLY
SOUTH OF INTERSTATE 80 AND INVOF I-55. NEAR TERM GUIDANCE
INDICATES THAT SOUTHERN BAND OF SNOW SHOWERS SHOULD WEAKEN SOME AS
IT ADVANCES EAST...WITH NARROWNESS OF FEATURE ONLY SUPPORTIVE OF
VERY BRIEF VISIBILITY REDUCTIONS AND A QUICK DUSTING TO MAYBE A
FEW TENTHS. IN FAR NORTHERN ILLINOIS...MORE SOLID AREA OF SNOW
ESPECIALLY OVER MCHENRY AND LAKE COUNTIES COULD BRING SOME LOCAL
ACCUMULATIONS TO NEAR AN INCH BEFORE ENDING EARLY THIS AFTERNOON.
RC
&&
.DISCUSSION...
349 AM CST
MAIN FORECAST CONCERNS REMAIN THE POTENTIAL FOR ACCUMULATING SNOW
SATURDAY FROM A FAST-MOVING CLIPPER...AND PRECIPITATION TYPE ISSUES
SUNDAY NIGHT THROUGH MONDAY WITH STRONG WARM ADVECTION DEVELOPING
INITIALLY ALOFT AND PRESENTING POTENTIAL FOR FREEZING RAIN BEFORE
SURFACE TEMPS RISE ABOVE FREEZING DURING THE DAY MONDAY. A COUPLE OF
MINOR ISSUES IN THE NEAR TERM ARE THE POTENTIAL FOR A PERIOD OF
LIGHT SNOW TODAY...AND ALSO THE CHANCE OF A LITTLE LIGHT SNOW FAR
SOUTH FRIDAY.
TODAY THROUGH FRIDAY...
EARLY MORNING WATER VAPOR IMAGERY DEPICTED A MID-LEVEL SHORT WAVE
TROUGH OVER THE EASTERN DAKOTAS...PROPAGATING EAST INTO THE UPPER
MISSISSIPPI VALLEY. AT THE SURFACE...993 MB LOW PRESSURE WAS OVER
NORTHEAST NORTH DAKOTA NEAR DEVILS LAKE. IMPRESSIVE SURFACE PRESSURE
FALLS IN EXCESS OF 7 MB/3 HRS WERE NOTED INTO WESTERN MINNESOTA
AHEAD OF THE LOW AND SOUTHWARD EXTENDING WARM FRONT...WITH AN AREA
OF SNOW NOTED IN REGIONAL RADAR MOSAICS AND SFC OBS. CLOSER TO
HOME...WEAK HIGH PRESSURE RIDGING LINGERED ACROSS OUR SOUTHEASTERN
CWA COUNTIES. CLEAR SKIES AND LIGHT WINDS WERE ALLOWING TEMPS TO DIP
BELOW ZERO IN A FEW SPOTS SOUTH OF CHICAGO...WHILE A PERSISTENT AREA
OF CLOUD COVER NORTH OF ABOUT A PERU-CHICAGO LINE WAS KEEPING TEMPS
THERE 15-20 ABOVE.
THE EASTERN DAKOTAS SHORT WAVE WILL CONTINUE TO PUSH EAST ACROSS THE
UPPER MISSISSIPPI VALLEY AND NORTHERN GREAT LAKES REGION TODAY AND
TONIGHT...WITH THE MAIN AREA OF DEEP ASCENT REMAINING NORTH OF THE
CWA ACROSS MN/WI/MICHIGAN. SOME DYNAMICS WILL BE IN PLAY THIS FAR
SOUTH HOWEVER...AHEAD OF MID-LEVEL TROUGH AXIS AND BENEATH LEFT
EXIT REGION OF STRONG UPPER JET STREAK TO OUR WEST. NARROW AXIS OF
MID-LEVEL SATURATION NOTED IN MODEL TIME SECTIONS...WHICH THEN WORKS
EAST OF THE CWA BY EARLY AFTERNOON. THIS IS COINCIDENT WITH SOME
FOCUSED ISENTROPIC ASCENT AROUND THE 295K THETA SURFACE WITHIN THE
DENDRITIC GROWTH ZONE...AND WITH RELATIVELY STEEP LAPSE RATES OF
7.0-7.5 C/KM NOTED ALOFT. WHILE THERE IS A DRY LAYER BETWEEN 900-700
MB...IT APPEARS DYNAMICS MAY BE SUFFICIENT TO PRODUCE A NARROW
NORTH-SOUTH BAND OF ELEVATED SNOW WHICH MOVES ACROSS THE AREA DURING
THE MID-MORNING TO EARLY AFTERNOON...WHICH COULD REACH THE GROUND IN
SOME SPOTS. WITH THIS IN MIND WILL CONTINUE TO CARRY A CHANCE POP
FOR A LOCAL DUSTING MAINLY ACROSS OUR NORTHERN TIER OF IL COUNTIES
DURING MIDDAY. SOME GUIDANCE...NOTABLY THE WRF-BASED RUNS...TRY TO
SQUEEZE OUT SOME VERY LIGHT QPF INTO THIS EVENING BEHIND THE COLD
FRONT WHICH MOVES THROUGH EARLY. FORECAST SOUNDINGS INDICATE DRY
MID/UPPER LEVELS WITH ONLY SHALLOW BOUNDARY LAYER MOISTURE PRESENT.
SEEMS UNLIKELY TO GET DRIZZLE OUT OF THIS SHALLOW MOIST LAYER...OR
ACTUALLY FREEZING DRIZZLE...AND HAVE MAINTAINED A DRY FORECAST
TONIGHT. FAVORING THE COOLER MET MOS FOR MAXES TODAY OVER SNOW
COVER...WITH A BLEND OF CLOSELY MATCHED GUIDANCE FOR COLDER TEMPS
TONIGHT.
GUIDANCE HAS TRENDED FARTHER SOUTH WITH A SHORT WAVE WHICH DIGS INTO
THE MISSOURI VALLEY EARLY FRIDAY...WITH PRECIP EXPECTED TO REMAIN
LARGELY OFF TO THE SOUTH/SOUTHWEST OF THE CWA DURING THE PERIOD.
HAVE ONLY BRUSHED THE ILX/LOT BORDER AREA WITH A 20-30 POP DURING
THE DAY FRIDAY...WITH ANY ACCUMULATION EXPECTED TO REMAIN SOUTH OF
THE CWA. COLDER TEMPS TEMPORARILY TO END THE WEEK...THOUGH WITH SOME
SUN EXPECTED IN THE AFTERNOON HAVE GONE AT/SLIGHTLY ABOVE MILDER MAV
MOS HIGHS. THE SAME CAN NOT BE SAID FOR FRIDAY NIGHT MINS...AS THE
CLEARING SKIES AND LIGHT WINDS WITHIN SURFACE RIDGE AXIS WHICH MOVES
OVER THE AREA ALLOWS FOR GOOD RADIATIONAL COOLING ONCE AGAIN...WITH
SINGLE DIGIT ABOVE AND BELOW ZERO LOWS ANTICIPATED AWAY FROM THE
CORE OF METRO CHICAGO.
SATURDAY AND SATURDAY NIGHT...
ATTENTION THEN TURNS TO A CLIPPER SYSTEM WHICH IS EXPECTED TO AFFECT
THE AREA SATURDAY AFTERNOON/EVENING...WITH THE POTENTIAL FOR A FEW
INCHES OF ACCUMULATION. 00Z MODELS REMAIN IN VERY GOOD AGREEMENT
WITH THEIR PREVIOUS RUNS AND WITH EACH OTHER IN HANDLING OF THIS
SYSTEM. MID-LEVEL VORT TRACK FROM NORTHERN IOWA INTO CENTRAL
ILLINOIS THROUGH SATURDAY EVENING CONTINUES TO FAVOR MAINLY THE
WEST/SOUTHWEST 1/2 OF THE CWA FOR THE AXIS OF ACCUMULATION...WHICH
STILL LOOKS TO BE IN A 1-3/2-4 INCH RANGE. MAINTAINED LIKELY POPS
ACROSS MUCH OF THE AREA IN THE EVENING...BEFORE SYSTEM QUICKLY
SCOOTS OFF TO THE SOUTHEAST AND SNOW ENDS FROM THE NORTHWEST.
SUNDAY THROUGH WEDNESDAY...
MEDIUM RANGE MODEL GUIDANCE CONTINUES TO INDICATE BROAD UPPER
RIDGING BUILDING OVER THE CENTRAL CONUS SATURDAY NIGHT AND
SUNDAY...WITH SURFACE HIGH PRESSURE RIDGE SUPPLYING DRY CONDITIONS
FOR US ON SUNDAY. MODELS ALSO CONTINUE TO DEVELOP AN UPPER TROUGH
OVER THE WESTERN CONUS...WHICH MOVES EAST AND INDUCES LOW PRESSURE
DEVELOPMENT ACROSS THE PLAINS MONDAY NIGHT. INCREASING SOUTHERLY
FLOW AND WARM/MOIST ADVECTION DEVELOP ACROSS THE MISSISSIPPI VALLEY
AND GREAT LAKES REGION OVERNIGHT...WITH PRECIPITATION DEVELOPING
INTO THE REGION BY MONDAY MORNING. STILL SOME SIGNIFICANT DETAIL
DIFFERENCES BETWEEN GFS/ECMWF AND GEM GUIDANCE AT THIS DISTANCE...
THOUGH IT DOES APPEAR THAT DEVELOPMENT OF A WARM (ABOVE FREEZING)
LAYER ALOFT WILL LEAD TO A MIX OF PRECIPITATION TYPES AT LEAST
INITIALLY. VARIOUS MODEL SOUNDINGS INDICATE A PERIOD OF
SNOW/SLEET/FREEZING RAIN IS POSSIBLE EARLY MONDAY MORNING...BEFORE
LOW LEVEL TEMPERATURES RISE ABOVE FREEZING AND DECREASE THE
SNOW/SLEET AND FREEZING RAIN POTENTIAL TO THAT OF MAINLY JUST RAIN.
ECMWF/GEM ARE BOTH COOLER WITHIN THE DEPTH OF THE COLUMN THAN THE
GFS...SO WILL HAVE TO MONITOR TRENDS IN THE GUIDANCE AS THEY SORT
OUT THE DETAILS OVER THE NEXT FEW DAYS.
FAIRLY GOOD AGREEMENT IN MODEL GUIDANCE THAT PRECIP SHOULD MOVE OUT
MONDAY EVENING...WITH A LULL IN THE ACTION TUESDAY AS WEAK SURFACE
RIDGE IS INDICATED. WEDNESDAY AND BEYOND LOOKS TO BE MILD AND
PERHAPS WET...AS GLOBAL MODELS ALL AMPLIFY UPPER TROUGH ACROSS THE
WEST AND MILD SOUTH WINDS INTO THE MIDWEST. 850 TEMPS FROM BOTH
ECMWF AND GFS APPROACH +10C WEDNESDAY...WITH PROSPECTS FOR EXCEEDING
40 DEGREES FOR THE FIRST TIME IN QUITE A WHILE! INSTEAD OF SUB-ZERO
COLD...SNOW MELT...RUNOFF AND FLOODING WILL THEN BE CONCERNS.
RATZER
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 18Z...
* SOUTH WINDS GUSTING TO 20 KT BECMG WEST THIS EVENING AND GUSTING
UP TO 25 KT FROM MID AFTERNOON ONWARD.
* LIGHT SNOW EARLY THIS AFTERNOON.
* MVFR CIGS TONIGHT AND POSSIBLE AGAIN FRIDAY AFTERNOON.
ZEBIC
//DISCUSSION...UPDATED 18Z...
NORTH-SOUTH BAND OF LIGHT SNOW AHEAD OF WARM FRONT TO MOVE OUT OF
THE TERMINAL AREA WITHIN THE NEXT FEW HOURS. WARM FRONT CROSSING MS
RIVER WILL BRING WIND MORE SOUTHWEST WITH MID AFTERNOON PASSAGE
AND A BRIEF SPELL OF WARMER TEMPERATURES.
ASSOCIATED LOW PRESSURE TO TRACK EAST ACROSS THE FAR NORTHERN
STRETCH OF THE REGION THIS AFTERNOON AND TONIGHT. TRAILING COLD
FRONT TO SWEEP ACROSS THE TERMINALS THIS EVENING. COLD AIR TO FILL
IN SLOWLY BEHIND FRONT AND ACROSS SNOW PACK LEADING CIGS TO LIKELY
FALL INTO THE MVFR RANGE INTO THE OVERNIGHT THEN COULD REDEVELOP WITH
DAYTIME HEATING TOMORROW.
FREEZING DRIZZLE CHANCES THIS EVENING REMAIN MINIMAL AND IF DOES
OCCUR WOULD LIKELY BE A NUISANCE AT WORSE.
ZEBIC
//ORD AND MDW CONFIDENCE...UPDATED 18Z...
* MEDIUM CONFIDENCE IN CIGS FCST.
* HIGH CONFIDENCE IN ALL OTHER FORECAST ELEMENTS.
ZEBIC
//OUTLOOK FOR ORD/MDW FOR 00Z SATURDAY-12Z THURSDAY...UPDATED 12Z...
FRIDAY NIGHT...VFR.
SATURDAY...SNOW IN THE AFTN AND EVENING...IFR LIKELY.
SUNDAY...CHC OF FREEZING RAIN OR ICE PELLETS OVERNIGHT. VFR BCMG
MVFR OR LOWER OVERNIGHT.
MONDAY...RAIN OR FREEZING RAIN IN THE MORNING BCMG RAIN OR SNOW IN
THE AFTN. DRY OVERNIGHT. IFR IMPROVING VFR OVERNIGHT.
TUESDAY...VFR.
WEDNESDAY...CHC OF RAIN. VFR BCMG MVFR OR LOWER.
JEE
&&
.MARINE...
318 AM CST
THE SURFACE RIDGE AXIS IS QUICKLY SHIFTING EAST BUT HAVE LIGHT SOUTH
WINDS. LOW PRESSURE IS OVER THE NORTHERN PLAINS AND SOUTH WINDS WILL
INCREASE TO 30 KT TODAY. THE LOW PASSES OVER THE LAKE THIS EVENING
AND WINDS VEER TO NW AT 30 KT BY FRIDAY MORNING. NW WINDS GRADUALLY
DIMINISH THROUGH FRIDAY NIGHT. A RIDGE OF HIGH PRESSURE PASSES OVER
THE LAKE SATURDAY AND WINDS WILL BE LIGHT ACROSS THE LAKE. THE NEXT
LOW PASSES WELL SOUTH OF THE LAKE AND REACHES THE WESTERN OHIO
VALLEY SATURDAY NIGHT. WINDS REMAIN LIGHT WITH DIRECTIONS VARYING
FROM EAST TO NORTHEAST. HIGH PRESSURE THEN SPREADS OVER THE LAKE
SUNDAY. WINDS TURN SE AND INCREASE IN SPEED AHEAD OF THE NEXT LOW
SUNDAY NIGHT. BY MONDAY MORNING WINDS WILL SE TO S TO 30 KT AND
THEN VEER TO WEST 10-20 KT MONDAY NIGHT BEHIND THE LOW. THE
REMAINDER OF EARLY NEXT WEEK LOOKS QUIET OVER THE LAKE.
JEE
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...NONE.
&&
$$
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Area Forecast Discussion
National Weather Service Lincoln IL
1150 AM CST Thu Feb 13 2014
.DISCUSSION...
ISSUED 954 AM CST Thu Feb 13 2014
Fast-moving clipper system is currently pushing into the Great
Lakes, while a trailing warm front approaches Illinois from the
west. Band of mid-level clouds accompanying the front has
occasionally produced some very light precip across eastern Iowa.
Despite rather dry 12z upper air soundings from both KDVN and
KILX, the HRRR tries to squeeze out some light QPF across the
Illinois River Valley over the next couple of hours. Based on
upstream reports of UP across eastern Iowa, have added a slight
chance for snow/sleet along/west of the Illinois River through
about 2pm. Band of clouds will quickly push eastward and out of
the area by mid to late afternoon, resulting in mostly sunny skies
across the board later today. Main story will be the much warmer
temps. Increasing southwesterly winds and ample sunshine will help
temps climb above the freezing mark. Despite deep snow cover,
think strong WAA will be enough to boost highs well into the 30s,
with lower 40s across the S/SE CWA. Have made several adjustments
to sky, temp, and POP grids. Zone update will be sent shortly.
Barnes
&&
.AVIATION...
ISSUED 1150 AM CST Thu Feb 13 2014
Several aviation concerns of note for the 18z TAFs. Band of
mid-level cloudiness currently in place over central Illinois
will quickly shift off to the east over the next couple of hours,
leaving behind mostly clear skies late this afternoon. First big
question is whether MVFR ceilings over Minnesota/northern Iowa
will rotate far enough southeast to impact any of the terminals
this evening. Satellite loops suggest most of this cloud cover will
remain to the north: however, HRRR has been consistently showing
clouds developing/spreading into north-central Illinois during the
evening. Will therefore include a 4-hour period of MVFR ceilings
at all sites except KSPI between 00z and 06z. Once these clouds
depart, only mid/high clouds will prevail through the night. Next
issues will be approach of clipper system and the timing of lower
ceilings and snow. 12z NAM/GFS fairly similar in aggressively
spreading snow across the area early Friday morning, with the
heaviest/steadiest snow focused south of the I-74 corridor. Based
on NAM forecast soundings, have introduced snow at KSPI as early
as 12z, then further northeast to KCMI by 15z. Will carry MVFR
ceilings at the I-74 terminals, but will go with lower IFR
ceilings at both KSPI and KDEC within the heavier snow band Friday
morning.
Barnes
&&
.PREV DISCUSSION...
ISSUED 320 AM CST Thu Feb 13 2014
Weather map getting increasingly complicated as the weather
shifts into a more active pattern. Deep wave crossing the srn tier
of the country and another small system moving across the nrn
plains this morning...both of these systems will start the more
active pattern. Though these two storm systems will not directly
impact the CWA, the systems that move into the wake of the more
amplified pattern aloft will bring a couple shots for snow going
into the weekend. Models showing some more consistency btwn
systems through the medium range forecast...if lacking in the
extended. Major warming trend through the forecast creating quite
the spread in the MOS as well. For now, the forecast remains
a conservative blend as the airmass begins to modify.
SHORT TERM...Today and tomorrow...
Partly cloudy skies today not enough to block some significant
warming as winds come around to the south and increasing
throughout the day as the high pressure ridge moves out to the
east. Temperatures will briefly climb above freezing today in most
locations. However, the temp increase will be brief and truncated
by another system for tomorrow. A quick short wave rippling down
from the nrn plains and into the Midwest bringing a shot of snow
to the FA, focusing more to the SW at this point, resulting in an
inch or two for areas southwest of a line from Lincoln to Decatur
to Mattoon. Last model runs slowed down the approach for this
storm, as a result have backed off the pops slightly for late
tonight into the early morning hours, but still should see the
precip developing to the west/southwest after midnight tonight.
Snow will diminish tomorrow evening.
LONG TERM...Saturday through Wednesday...
Another quick wave dives into the Midwest, bringing the best lift
to the NErn portion of the CWA...with another similar inch or two
along and northeast of a line from Galesburg to Champaign.
Temperatures on Sunday will struggle to climb towards freezing,
and the early morning temps will be in the 20s after
midnight/Monday morning. Precipitation spreading ahead of a larger
developing system in the early hours of Monday morning will fall
through a deep mid level warm layer has pushed the forecast to
freezing rain. Available moisture will have to work through some
dry air at first, keeping qpf low...as well as probability at this
point, but the threat for fzra remains that morning. As the temp
rises, and the precip continues to develop with the stronger lift
of the main wave...should go to all rain for Monday while the
temperatures are progged to climb into the 40s. Forecast still
optimistic though there will be a lot of snow to melt...as the
southerly winds will def assist the thaw. Temperatures even warmer
after a cooler day on Tues behind the precip...with AllBlend
pushing the maxT on Wednesday to 40s and 50s.
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
1123 AM CST THU FEB 13 2014
.MESOSCALE DISCUSSION...
1122 AM CST
LATEST SPC MESOANALYSIS INDICATES VERY STEEP MIDLEVEL LAPSE RATES
OF 7-8C/KM ACROSS NORTHERN ILLINOIS IN PLACE WITH ADVANCING WARM
FRONT TRAILING FROM CLIPPER NORTH OF MSP. COMBINED WITH MIDLEVEL
SPEED MAX PUNCHING INTO AREA NOTED ON W/V IMAGERY...THIS HAS
RESULTED IN BROKEN BAND OF SNOW SHOWERS PUSHING EAST. GIVEN THE
STEEP MIDLEVEL LAPSE RATES...BRIEF MODERATE TO HEAVY SNOW RATES
ARE OCCURRING IN THE SNOW SHOWERS...MOST PROMINENTLY ACROSS FAR
NORTHERN ILLINOIS AND IN ANOTHER BAND ADVANCING EASTWARD CURRENTLY
SOUTH OF INTERSTATE 80 AND INVOF I-55. NEAR TERM GUIDANCE
INDICATES THAT SOUTHERN BAND OF SNOW SHOWERS SHOULD WEAKEN SOME AS
IT ADVANCES EAST...WITH NARROWNESS OF FEATURE ONLY SUPPORTIVE OF
VERY BRIEF VISIBILITY REDUCTIONS AND A QUICK DUSTING TO MAYBE A
FEW TENTHS. IN FAR NORTHERN ILLINOIS...MORE SOLID AREA OF SNOW
ESPECIALLY OVER MCHENRY AND LAKE COUNTIES COULD BRING SOME LOCAL
ACCUMULATIONS TO NEAR AN INCH BEFORE ENDING EARLY THIS AFTERNOON.
RC
&&
.DISCUSSION...
349 AM CST
MAIN FORECAST CONCERNS REMAIN THE POTENTIAL FOR ACCUMULATING SNOW
SATURDAY FROM A FAST-MOVING CLIPPER...AND PRECIPITATION TYPE ISSUES
SUNDAY NIGHT THROUGH MONDAY WITH STRONG WARM ADVECTION DEVELOPING
INITIALLY ALOFT AND PRESENTING POTENTIAL FOR FREEZING RAIN BEFORE
SURFACE TEMPS RISE ABOVE FREEZING DURING THE DAY MONDAY. A COUPLE OF
MINOR ISSUES IN THE NEAR TERM ARE THE POTENTIAL FOR A PERIOD OF
LIGHT SNOW TODAY...AND ALSO THE CHANCE OF A LITTLE LIGHT SNOW FAR
SOUTH FRIDAY.
TODAY THROUGH FRIDAY...
EARLY MORNING WATER VAPOR IMAGERY DEPICTED A MID-LEVEL SHORT WAVE
TROUGH OVER THE EASTERN DAKOTAS...PROPAGATING EAST INTO THE UPPER
MISSISSIPPI VALLEY. AT THE SURFACE...993 MB LOW PRESSURE WAS OVER
NORTHEAST NORTH DAKOTA NEAR DEVILS LAKE. IMPRESSIVE SURFACE PRESSURE
FALLS IN EXCESS OF 7 MB/3 HRS WERE NOTED INTO WESTERN MINNESOTA
AHEAD OF THE LOW AND SOUTHWARD EXTENDING WARM FRONT...WITH AN AREA
OF SNOW NOTED IN REGIONAL RADAR MOSAICS AND SFC OBS. CLOSER TO
HOME...WEAK HIGH PRESSURE RIDGING LINGERED ACROSS OUR SOUTHEASTERN
CWA COUNTIES. CLEAR SKIES AND LIGHT WINDS WERE ALLOWING TEMPS TO DIP
BELOW ZERO IN A FEW SPOTS SOUTH OF CHICAGO...WHILE A PERSISTENT AREA
OF CLOUD COVER NORTH OF ABOUT A PERU-CHICAGO LINE WAS KEEPING TEMPS
THERE 15-20 ABOVE.
THE EASTERN DAKOTAS SHORT WAVE WILL CONTINUE TO PUSH EAST ACROSS THE
UPPER MISSISSIPPI VALLEY AND NORTHERN GREAT LAKES REGION TODAY AND
TONIGHT...WITH THE MAIN AREA OF DEEP ASCENT REMAINING NORTH OF THE
CWA ACROSS MN/WI/MICHIGAN. SOME DYNAMICS WILL BE IN PLAY THIS FAR
SOUTH HOWEVER...AHEAD OF MID-LEVEL TROUGH AXIS AND BENEATH LEFT
EXIT REGION OF STRONG UPPER JET STREAK TO OUR WEST. NARROW AXIS OF
MID-LEVEL SATURATION NOTED IN MODEL TIME SECTIONS...WHICH THEN WORKS
EAST OF THE CWA BY EARLY AFTERNOON. THIS IS COINCIDENT WITH SOME
FOCUSED ISENTROPIC ASCENT AROUND THE 295K THETA SURFACE WITHIN THE
DENDRITIC GROWTH ZONE...AND WITH RELATIVELY STEEP LAPSE RATES OF
7.0-7.5 C/KM NOTED ALOFT. WHILE THERE IS A DRY LAYER BETWEEN 900-700
MB...IT APPEARS DYNAMICS MAY BE SUFFICIENT TO PRODUCE A NARROW
NORTH-SOUTH BAND OF ELEVATED SNOW WHICH MOVES ACROSS THE AREA DURING
THE MID-MORNING TO EARLY AFTERNOON...WHICH COULD REACH THE GROUND IN
SOME SPOTS. WITH THIS IN MIND WILL CONTINUE TO CARRY A CHANCE POP
FOR A LOCAL DUSTING MAINLY ACROSS OUR NORTHERN TIER OF IL COUNTIES
DURING MIDDAY. SOME GUIDANCE...NOTABLY THE WRF-BASED RUNS...TRY TO
SQUEEZE OUT SOME VERY LIGHT QPF INTO THIS EVENING BEHIND THE COLD
FRONT WHICH MOVES THROUGH EARLY. FORECAST SOUNDINGS INDICATE DRY
MID/UPPER LEVELS WITH ONLY SHALLOW BOUNDARY LAYER MOISTURE PRESENT.
SEEMS UNLIKELY TO GET DRIZZLE OUT OF THIS SHALLOW MOIST LAYER...OR
ACTUALLY FREEZING DRIZZLE...AND HAVE MAINTAINED A DRY FORECAST
TONIGHT. FAVORING THE COOLER MET MOS FOR MAXES TODAY OVER SNOW
COVER...WITH A BLEND OF CLOSELY MATCHED GUIDANCE FOR COLDER TEMPS
TONIGHT.
GUIDANCE HAS TRENDED FARTHER SOUTH WITH A SHORT WAVE WHICH DIGS INTO
THE MISSOURI VALLEY EARLY FRIDAY...WITH PRECIP EXPECTED TO REMAIN
LARGELY OFF TO THE SOUTH/SOUTHWEST OF THE CWA DURING THE PERIOD.
HAVE ONLY BRUSHED THE ILX/LOT BORDER AREA WITH A 20-30 POP DURING
THE DAY FRIDAY...WITH ANY ACCUMULATION EXPECTED TO REMAIN SOUTH OF
THE CWA. COLDER TEMPS TEMPORARILY TO END THE WEEK...THOUGH WITH SOME
SUN EXPECTED IN THE AFTERNOON HAVE GONE AT/SLIGHTLY ABOVE MILDER MAV
MOS HIGHS. THE SAME CAN NOT BE SAID FOR FRIDAY NIGHT MINS...AS THE
CLEARING SKIES AND LIGHT WINDS WITHIN SURFACE RIDGE AXIS WHICH MOVES
OVER THE AREA ALLOWS FOR GOOD RADIATIONAL COOLING ONCE AGAIN...WITH
SINGLE DIGIT ABOVE AND BELOW ZERO LOWS ANTICIPATED AWAY FROM THE
CORE OF METRO CHICAGO.
SATURDAY AND SATURDAY NIGHT...
ATTENTION THEN TURNS TO A CLIPPER SYSTEM WHICH IS EXPECTED TO AFFECT
THE AREA SATURDAY AFTERNOON/EVENING...WITH THE POTENTIAL FOR A FEW
INCHES OF ACCUMULATION. 00Z MODELS REMAIN IN VERY GOOD AGREEMENT
WITH THEIR PREVIOUS RUNS AND WITH EACH OTHER IN HANDLING OF THIS
SYSTEM. MID-LEVEL VORT TRACK FROM NORTHERN IOWA INTO CENTRAL
ILLINOIS THROUGH SATURDAY EVENING CONTINUES TO FAVOR MAINLY THE
WEST/SOUTHWEST 1/2 OF THE CWA FOR THE AXIS OF ACCUMULATION...WHICH
STILL LOOKS TO BE IN A 1-3/2-4 INCH RANGE. MAINTAINED LIKELY POPS
ACROSS MUCH OF THE AREA IN THE EVENING...BEFORE SYSTEM QUICKLY
SCOOTS OFF TO THE SOUTHEAST AND SNOW ENDS FROM THE NORTHWEST.
SUNDAY THROUGH WEDNESDAY...
MEDIUM RANGE MODEL GUIDANCE CONTINUES TO INDICATE BROAD UPPER
RIDGING BUILDING OVER THE CENTRAL CONUS SATURDAY NIGHT AND
SUNDAY...WITH SURFACE HIGH PRESSURE RIDGE SUPPLYING DRY CONDITIONS
FOR US ON SUNDAY. MODELS ALSO CONTINUE TO DEVELOP AN UPPER TROUGH
OVER THE WESTERN CONUS...WHICH MOVES EAST AND INDUCES LOW PRESSURE
DEVELOPMENT ACROSS THE PLAINS MONDAY NIGHT. INCREASING SOUTHERLY
FLOW AND WARM/MOIST ADVECTION DEVELOP ACROSS THE MISSISSIPPI VALLEY
AND GREAT LAKES REGION OVERNIGHT...WITH PRECIPITATION DEVELOPING
INTO THE REGION BY MONDAY MORNING. STILL SOME SIGNIFICANT DETAIL
DIFFERENCES BETWEEN GFS/ECMWF AND GEM GUIDANCE AT THIS DISTANCE...
THOUGH IT DOES APPEAR THAT DEVELOPMENT OF A WARM (ABOVE FREEZING)
LAYER ALOFT WILL LEAD TO A MIX OF PRECIPITATION TYPES AT LEAST
INITIALLY. VARIOUS MODEL SOUNDINGS INDICATE A PERIOD OF
SNOW/SLEET/FREEZING RAIN IS POSSIBLE EARLY MONDAY MORNING...BEFORE
LOW LEVEL TEMPERATURES RISE ABOVE FREEZING AND DECREASE THE
SNOW/SLEET AND FREEZING RAIN POTENTIAL TO THAT OF MAINLY JUST RAIN.
ECMWF/GEM ARE BOTH COOLER WITHIN THE DEPTH OF THE COLUMN THAN THE
GFS...SO WILL HAVE TO MONITOR TRENDS IN THE GUIDANCE AS THEY SORT
OUT THE DETAILS OVER THE NEXT FEW DAYS.
FAIRLY GOOD AGREEMENT IN MODEL GUIDANCE THAT PRECIP SHOULD MOVE OUT
MONDAY EVENING...WITH A LULL IN THE ACTION TUESDAY AS WEAK SURFACE
RIDGE IS INDICATED. WEDNESDAY AND BEYOND LOOKS TO BE MILD AND
PERHAPS WET...AS GLOBAL MODELS ALL AMPLIFY UPPER TROUGH ACROSS THE
WEST AND MILD SOUTH WINDS INTO THE MIDWEST. 850 TEMPS FROM BOTH
ECMWF AND GFS APPROACH +10C WEDNESDAY...WITH PROSPECTS FOR EXCEEDING
40 DEGREES FOR THE FIRST TIME IN QUITE A WHILE! INSTEAD OF SUB-ZERO
COLD...SNOW MELT...RUNOFF AND FLOODING WILL THEN BE CONCERNS.
RATZER
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 14Z...
* SOUTH WINDS GUSTING TO 20 KT BECMG WEST THIS EVENING AND GUSTING
UP TO 25 KT FROM MID AFTERNOON ONWARD.
* POTENTIAL FOR A SHORT 1 TO 2 HOUR PERIOD OF SNOW EARLY THIS
AFTN...WITH A BRF PERIOD OF MVFR VIS PSBL.
* MVFR-VFR CIGS ACCOMPANY THE SNOW AND LINGER OVERNIGHT.
JEE/DZ
//DISCUSSION...UPDATED 12Z...
HIGH PRESSURE REMAINS OVER THE REGION BUT LOW PRESSURE IS PUSHING
EAST INTO MINNESOTA. THE LOW END VFR CLOUD COVER HAS DISSIPATED
AND EXPECTING TO HAVE BKN CIRRUS LAYER OVERHEAD THROUGH MID
MORNING. WINDS WILL INCREASE BY MID MORNING AND GUST TO 20KT. MAX
GUSTS ARND 25 KT ARE EXPECTED THIS AFTN AND WINDS WILL BECOME WEST
BEHIND THE COLD FRONT THIS EVENING. GUSTS DIMINISH AFTER MIDNIGHT
AND WINDS SLOWLY TURN TO NW BY FRIDAY MORNING.
FOR PRECIP...A COUPLE OF BANDS OF PRECIP ARE OVER IA...BUT
THINKING THE FIRST BAND WILL DISSIPATE BEFORE IT REACHES RFD. THE
SECOND BAND SHOULD HAVE BETTER FORCING SINCE IT WILL COLLOCATED WITH
THE WARM FRONT. SNOW SHOULD FALL FOR NO LONGER THAN AN HOUR AT
EACH TERMINAL BUT LEFT A 2 HOUR WINDOW IN THE TAFS. STILL NOT SURE
ABOUT THE EXACT TIMING...HENCE THE WINDOW. IFR VSBY STILL LOOKS
REASONABLE ESPECIALLY SINCE MOST SITES UPSTREAM ARE NO LOWER THAN
1 SM. CIGS WILL LOWER TO MVFR WITH THE SNOW AND THEN REMAIN THERE
OVERNIGHT.
STILL DID NOT INCLUDE ANY FREEZING DRIZZLE THIS EVENING AS
CONDITIONS ARE NOT IDEAL. HOWEVER WILL CONTINUE TO MENTION IT HERE
AS FREEZING DRIZZLE WILL LIKELY BE A NUISANCE TO OPERATIONS. IF WE
SEE ANY FREEZING DRIZZLE IT WOULD LIKELY BE BETWEEN 02Z AND 08Z.
OTHERWISE CONDITIONS IMPROVE FRIDAY MORNING TO VFR.
JEE
//ORD AND MDW CONFIDENCE...UPDATED 14Z...
* MEDIUM-LOW CONFIDENCE IN EXACT TIMING OF LIGHT SNOW THIS AFTN
AND HOW LOW VIS WILL DROP...BUT HIGH CONFIDENCE LIGHT SNOW
SHOULD ONLY LAST AN HOUR OR MAYBE TWO.
* HIGH CONFIDENCE IN ALL OTHER FORECAST ELEMENTS.
JEE/DZ
//OUTLOOK FOR ORD/MDW FOR 00Z SATURDAY-12Z THURSDAY...UPDATED 12Z...
FRIDAY NIGHT...VFR.
SATURDAY...SNOW IN THE AFTN AND EVENING...IFR LIKELY.
SUNDAY...CHC OF FREEZING RAIN OR ICE PELLETS OVERNIGHT. VFR BCMG
MVFR OR LOWER OVERNIGHT.
MONDAY...RAIN OR FREEZING RAIN IN THE MORNING BCMG RAIN OR SNOW IN
THE AFTN. DRY OVERNIGHT. IFR IMPROVING VFR OVERNIGHT.
TUESDAY...VFR.
WEDNESDAY...CHC OF RAIN. VFR BCMG MVFR OR LOWER.
JEE
&&
.MARINE...
318 AM CST
THE SURFACE RIDGE AXIS IS QUICKLY SHIFTING EAST BUT HAVE LIGHT SOUTH
WINDS. LOW PRESSURE IS OVER THE NORTHERN PLAINS AND SOUTH WINDS WILL
INCREASE TO 30 KT TODAY. THE LOW PASSES OVER THE LAKE THIS EVENING
AND WINDS VEER TO NW AT 30 KT BY FRIDAY MORNING. NW WINDS GRADUALLY
DIMINISH THROUGH FRIDAY NIGHT. A RIDGE OF HIGH PRESSURE PASSES OVER
THE LAKE SATURDAY AND WINDS WILL BE LIGHT ACROSS THE LAKE. THE NEXT
LOW PASSES WELL SOUTH OF THE LAKE AND REACHES THE WESTERN OHIO
VALLEY SATURDAY NIGHT. WINDS REMAIN LIGHT WITH DIRECTIONS VARYING
FROM EAST TO NORTHEAST. HIGH PRESSURE THEN SPREADS OVER THE LAKE
SUNDAY. WINDS TURN SE AND INCREASE IN SPEED AHEAD OF THE NEXT LOW
SUNDAY NIGHT. BY MONDAY MORNING WINDS WILL SE TO S TO 30 KT AND
THEN VEER TO WEST 10-20 KT MONDAY NIGHT BEHIND THE LOW. THE
REMAINDER OF EARLY NEXT WEEK LOOKS QUIET OVER THE LAKE.
JEE
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...NONE.
&&
$$
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Area Forecast Discussion
National Weather Service Lincoln IL
954 AM CST Thu Feb 13 2014
.DISCUSSION...
ISSUED 954 AM CST Thu Feb 13 2014
Fast-moving clipper system is currently pushing into the Great
Lakes, while a trailing warm front approaches Illinois from the
west. Band of mid-level clouds accompanying the front has
occasionally produced some very light precip across eastern Iowa.
Despite rather dry 12z upper air soundings from both KDVN and
KILX, the HRRR tries to squeeze out some light QPF across the
Illinois River Valley over the next couple of hours. Based on
upstream reports of UP across eastern Iowa, have added a slight
chance for snow/sleet along/west of the Illinois River through
about 2pm. Band of clouds will quickly push eastward and out of
the area by mid to late afternoon, resulting in mostly sunny skies
across the board later today. Main story will be the much warmer
temps. Increasing southwesterly winds and ample sunshine will help
temps climb above the freezing mark. Despite deep snow cover,
think strong WAA will be enough to boost highs well into the 30s,
with lower 40s across the S/SE CWA. Have made several adjustments
to sky, temp, and POP grids. Zone update will be sent shortly.
Barnes
&&
.AVIATION...
ISSUED 525 AM CST Thu Feb 13 2014
Main forecast concern will be with MVFR cigs west of the Mississippi
River early this morning and how far east they will track this morning
into our area, and then with the timing of snow into central Illinois
late in this forecast period.
Weather system tracking well to our north will take most of the
snow and rain to the north of our forecast area as well. However,
a band of MVFR cigs was noted on satellite data over east central
Iowa and was tracking east. Latest short term forecasts off the
HRRR and WRF ensembles suggest a decrease in coverage expected this
morning as it encounters a very dry air mass over our area as high
pressure is slow to depart. Models have trended back on the coverage
of the MVFR and in some cases pockets of IFR cigs late this morning
into the afternoon hours. Still a concern for PIA and BMI so will
keep at least a scattered to broken MVFR cig in those locations while
scaling back the amount of low cloud cover further south.
The next system will be racing southeast into the Plains states this
evening and will begin to affect SPI after 09z. Based on forecast
sounding data, have opted to leave out of this set of TAFs as the low
level dry air ahead of the storm will tend to delay the onset of the
precip late tonight. Surface winds will become south to southwest
today at 10 to 15 kts with gusts up to 20-24kts by afternoon most
areas. We should see the gusts gradually diminish towards 00z with
directions veering more into a westerly component early this evening.
Smith
&&
.PREV DISCUSSION...
ISSUED 320 AM CST Thu Feb 13 2014
Weather map getting increasingly complicated as the weather
shifts into a more active pattern. Deep wave crossing the srn tier
of the country and another small system moving across the nrn
plains this morning...both of these systems will start the more
active pattern. Though these two storm systems will not directly
impact the CWA, the systems that move into the wake of the more
amplified pattern aloft will bring a couple shots for snow going
into the weekend. Models showing some more consistency btwn
systems through the medium range forecast...if lacking in the
extended. Major warming trend through the forecast creating quite
the spread in the MOS as well. For now, the forecast remains
a conservative blend as the airmass begins to modify.
SHORT TERM...Today and tomorrow...
Partly cloudy skies today not enough to block some significant
warming as winds come around to the south and increasing
throughout the day as the high pressure ridge moves out to the
east. Temperatures will briefly climb above freezing today in most
locations. However, the temp increase will be brief and truncated
by another system for tomorrow. A quick short wave rippling down
from the nrn plains and into the Midwest bringing a shot of snow
to the FA, focusing more to the SW at this point, resulting in an
inch or two for areas southwest of a line from Lincoln to Decatur
to Mattoon. Last model runs slowed down the approach for this
storm, as a result have backed off the pops slightly for late
tonight into the early morning hours, but still should see the
precip developing to the west/southwest after midnight tonight.
Snow will diminish tomorrow evening.
LONG TERM...Saturday through Wednesday...
Another quick wave dives into the Midwest, bringing the best lift
to the NErn portion of the CWA...with another similar inch or two
along and northeast of a line from Galesburg to Champaign.
Temperatures on Sunday will struggle to climb towards freezing,
and the early morning temps will be in the 20s after
midnight/Monday morning. Precipitation spreading ahead of a larger
developing system in the early hours of Monday morning will fall
through a deep mid level warm layer has pushed the forecast to
freezing rain. Available moisture will have to work through some
dry air at first, keeping qpf low...as well as probability at this
point, but the threat for fzra remains that morning. As the temp
rises, and the precip continues to develop with the stronger lift
of the main wave...should go to all rain for Monday while the
temperatures are progged to climb into the 40s. Forecast still
optimistic though there will be a lot of snow to melt...as the
southerly winds will def assist the thaw. Temperatures even warmer
after a cooler day on Tues behind the precip...with AllBlend
pushing the maxT on Wednesday to 40s and 50s.
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
547 AM CST THU FEB 13 2014
.DISCUSSION...
349 AM CST
MAIN FORECAST CONCERNS REMAIN THE POTENTIAL FOR ACCUMULATING SNOW
SATURDAY FROM A FAST-MOVING CLIPPER...AND PRECIPITATION TYPE ISSUES
SUNDAY NIGHT THROUGH MONDAY WITH STRONG WARM ADVECTION DEVELOPING
INITIALLY ALOFT AND PRESENTING POTENTIAL FOR FREEZING RAIN BEFORE
SURFACE TEMPS RISE ABOVE FREEZING DURING THE DAY MONDAY. A COUPLE OF
MINOR ISSUES IN THE NEAR TERM ARE THE POTENTIAL FOR A PERIOD OF
LIGHT SNOW TODAY...AND ALSO THE CHANCE OF A LITTLE LIGHT SNOW FAR
SOUTH FRIDAY.
TODAY THROUGH FRIDAY...
EARLY MORNING WATER VAPOR IMAGERY DEPICTED A MID-LEVEL SHORT WAVE
TROUGH OVER THE EASTERN DAKOTAS...PROPAGATING EAST INTO THE UPPER
MISSISSIPPI VALLEY. AT THE SURFACE...993 MB LOW PRESSURE WAS OVER
NORTHEAST NORTH DAKOTA NEAR DEVILS LAKE. IMPRESSIVE SURFACE PRESSURE
FALLS IN EXCESS OF 7 MB/3 HRS WERE NOTED INTO WESTERN MINNESOTA
AHEAD OF THE LOW AND SOUTHWARD EXTENDING WARM FRONT...WITH AN AREA
OF SNOW NOTED IN REGIONAL RADAR MOSAICS AND SFC OBS. CLOSER TO
HOME...WEAK HIGH PRESSURE RIDGING LINGERED ACROSS OUR SOUTHEASTERN
CWA COUNTIES. CLEAR SKIES AND LIGHT WINDS WERE ALLOWING TEMPS TO DIP
BELOW ZERO IN A FEW SPOTS SOUTH OF CHICAGO...WHILE A PERSISTENT AREA
OF CLOUD COVER NORTH OF ABOUT A PERU-CHICAGO LINE WAS KEEPING TEMPS
THERE 15-20 ABOVE.
THE EASTERN DAKOTAS SHORT WAVE WILL CONTINUE TO PUSH EAST ACROSS THE
UPPER MISSISSIPPI VALLEY AND NORTHERN GREAT LAKES REGION TODAY AND
TONIGHT...WITH THE MAIN AREA OF DEEP ASCENT REMAINING NORTH OF THE
CWA ACROSS MN/WI/MICHIGAN. SOME DYNAMICS WILL BE IN PLAY THIS FAR
SOUTH HOWEVER...AHEAD OF MID-LEVEL TROUGH AXIS AND BENEATH LEFT
EXIT REGION OF STRONG UPPER JET STREAK TO OUR WEST. NARROW AXIS OF
MID-LEVEL SATURATION NOTED IN MODEL TIME SECTIONS...WHICH THEN WORKS
EAST OF THE CWA BY EARLY AFTERNOON. THIS IS COINCIDENT WITH SOME
FOCUSED ISENTROPIC ASCENT AROUND THE 295K THETA SURFACE WITHIN THE
DENDRITIC GROWTH ZONE...AND WITH RELATIVELY STEEP LAPSE RATES OF
7.0-7.5 C/KM NOTED ALOFT. WHILE THERE IS A DRY LAYER BETWEEN 900-700
MB...IT APPEARS DYNAMICS MAY BE SUFFICIENT TO PRODUCE A NARROW
NORTH-SOUTH BAND OF ELEVATED SNOW WHICH MOVES ACROSS THE AREA DURING
THE MID-MORNING TO EARLY AFTERNOON...WHICH COULD REACH THE GROUND IN
SOME SPOTS. WITH THIS IN MIND WILL CONTINUE TO CARRY A CHANCE POP
FOR A LOCAL DUSTING MAINLY ACROSS OUR NORTHERN TIER OF IL COUNTIES
DURING MIDDAY. SOME GUIDANCE...NOTABLY THE WRF-BASED RUNS...TRY TO
SQUEEZE OUT SOME VERY LIGHT QPF INTO THIS EVENING BEHIND THE COLD
FRONT WHICH MOVES THROUGH EARLY. FORECAST SOUNDINGS INDICATE DRY
MID/UPPER LEVELS WITH ONLY SHALLOW BOUNDARY LAYER MOISTURE PRESENT.
SEEMS UNLIKELY TO GET DRIZZLE OUT OF THIS SHALLOW MOIST LAYER...OR
ACTUALLY FREEZING DRIZZLE...AND HAVE MAINTAINED A DRY FORECAST
TONIGHT. FAVORING THE COOLER MET MOS FOR MAXES TODAY OVER SNOW
COVER...WITH A BLEND OF CLOSELY MATCHED GUIDANCE FOR COLDER TEMPS
TONIGHT.
GUIDANCE HAS TRENDED FARTHER SOUTH WITH A SHORT WAVE WHICH DIGS INTO
THE MISSOURI VALLEY EARLY FRIDAY...WITH PRECIP EXPECTED TO REMAIN
LARGELY OFF TO THE SOUTH/SOUTHWEST OF THE CWA DURING THE PERIOD.
HAVE ONLY BRUSHED THE ILX/LOT BORDER AREA WITH A 20-30 POP DURING
THE DAY FRIDAY...WITH ANY ACCUMULATION EXPECTED TO REMAIN SOUTH OF
THE CWA. COLDER TEMPS TEMPORARILY TO END THE WEEK...THOUGH WITH SOME
SUN EXPECTED IN THE AFTERNOON HAVE GONE AT/SLIGHTLY ABOVE MILDER MAV
MOS HIGHS. THE SAME CAN NOT BE SAID FOR FRIDAY NIGHT MINS...AS THE
CLEARING SKIES AND LIGHT WINDS WITHIN SURFACE RIDGE AXIS WHICH MOVES
OVER THE AREA ALLOWS FOR GOOD RADIATIONAL COOLING ONCE AGAIN...WITH
SINGLE DIGIT ABOVE AND BELOW ZERO LOWS ANTICIPATED AWAY FROM THE
CORE OF METRO CHICAGO.
SATURDAY AND SATURDAY NIGHT...
ATTENTION THEN TURNS TO A CLIPPER SYSTEM WHICH IS EXPECTED TO AFFECT
THE AREA SATURDAY AFTERNOON/EVENING...WITH THE POTENTIAL FOR A FEW
INCHES OF ACCUMULATION. 00Z MODELS REMAIN IN VERY GOOD AGREEMENT
WITH THEIR PREVIOUS RUNS AND WITH EACH OTHER IN HANDLING OF THIS
SYSTEM. MID-LEVEL VORT TRACK FROM NORTHERN IOWA INTO CENTRAL
ILLINOIS THROUGH SATURDAY EVENING CONTINUES TO FAVOR MAINLY THE
WEST/SOUTHWEST 1/2 OF THE CWA FOR THE AXIS OF ACCUMULATION...WHICH
STILL LOOKS TO BE IN A 1-3/2-4 INCH RANGE. MAINTAINED LIKELY POPS
ACROSS MUCH OF THE AREA IN THE EVENING...BEFORE SYSTEM QUICKLY
SCOOTS OFF TO THE SOUTHEAST AND SNOW ENDS FROM THE NORTHWEST.
SUNDAY THROUGH WEDNESDAY...
MEDIUM RANGE MODEL GUIDANCE CONTINUES TO INDICATE BROAD UPPER
RIDGING BUILDING OVER THE CENTRAL CONUS SATURDAY NIGHT AND
SUNDAY...WITH SURFACE HIGH PRESSURE RIDGE SUPPLYING DRY CONDITIONS
FOR US ON SUNDAY. MODELS ALSO CONTINUE TO DEVELOP AN UPPER TROUGH
OVER THE WESTERN CONUS...WHICH MOVES EAST AND INDUCES LOW PRESSURE
DEVELOPMENT ACROSS THE PLAINS MONDAY NIGHT. INCREASING SOUTHERLY
FLOW AND WARM/MOIST ADVECTION DEVELOP ACROSS THE MISSISSIPPI VALLEY
AND GREAT LAKES REGION OVERNIGHT...WITH PRECIPITATION DEVELOPING
INTO THE REGION BY MONDAY MORNING. STILL SOME SIGNIFICANT DETAIL
DIFFERENCES BETWEEN GFS/ECMWF AND GEM GUIDANCE AT THIS DISTANCE...
THOUGH IT DOES APPEAR THAT DEVELOPMENT OF A WARM (ABOVE FREEZING)
LAYER ALOFT WILL LEAD TO A MIX OF PRECIPITATION TYPES AT LEAST
INITIALLY. VARIOUS MODEL SOUNDINGS INDICATE A PERIOD OF
SNOW/SLEET/FREEZING RAIN IS POSSIBLE EARLY MONDAY MORNING...BEFORE
LOW LEVEL TEMPERATURES RISE ABOVE FREEZING AND DECREASE THE
SNOW/SLEET AND FREEZING RAIN POTENTIAL TO THAT OF MAINLY JUST RAIN.
ECMWF/GEM ARE BOTH COOLER WITHIN THE DEPTH OF THE COLUMN THAN THE
GFS...SO WILL HAVE TO MONITOR TRENDS IN THE GUIDANCE AS THEY SORT
OUT THE DETAILS OVER THE NEXT FEW DAYS.
FAIRLY GOOD AGREEMENT IN MODEL GUIDANCE THAT PRECIP SHOULD MOVE OUT
MONDAY EVENING...WITH A LULL IN THE ACTION TUESDAY AS WEAK SURFACE
RIDGE IS INDICATED. WEDNESDAY AND BEYOND LOOKS TO BE MILD AND
PERHAPS WET...AS GLOBAL MODELS ALL AMPLIFY UPPER TROUGH ACROSS THE
WEST AND MILD SOUTH WINDS INTO THE MIDWEST. 850 TEMPS FROM BOTH
ECMWF AND GFS APPROACH +10C WEDNESDAY...WITH PROSPECTS FOR EXCEEDING
40 DEGREES FOR THE FIRST TIME IN QUITE A WHILE! INSTEAD OF SUB-ZERO
COLD...SNOW MELT...RUNOFF AND FLOODING WILL THEN BE CONCERNS.
RATZER
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 12Z...
* SOUTH WINDS GUSTING TO 20 KT BCMG WEST THIS EVENING AND GUSTING
UP TO 25 KT FROM MID AFTERNOON ONWARD.
* POTENTIAL FOR A SHORT 1 TO 2 HOUR PERIOD OF SNOW EARLY THIS
AFTN...WITH A SHORT PERIOD OF IFR...MAYBE LIFR...VSBY PSBL.
* MVFR CIGS ACCOMPANY THE SNOW AND LINGER OVERNIGHT.
JEE
//DISCUSSION...UPDATED 12Z...
HIGH PRESSURE REMAINS OVER THE REGION BUT LOW PRESSURE IS PUSHING
EAST INTO MINNESOTA. THE LOW END VFR CLOUD COVER HAS DISSIPATED
AND EXPECTING TO HAVE BKN CIRRUS LAYER OVERHEAD THROUGH MID
MORNING. WINDS WILL INCREASE BY MID MORNING AND GUST TO 20KT. MAX
GUSTS ARND 25 KT ARE EXPECTED THIS AFTN AND WINDS WILL BECOME WEST
BEHIND THE COLD FRONT THIS EVENING. GUSTS DIMINISH AFTER MIDNIGHT
AND WINDS SLOWLY TURN TO NW BY FRIDAY MORNING.
FOR PRECIP...A COUPLE OF BANDS OF PRECIP ARE OVER IA...BUT
THINKING THE FIRST BAND WILL DISSIPATE BEFORE IT REACHES RFD. THE
SECOND BAND SHOULD HAVE BETTER FORCING SINCE IT WILL COLLOCATED WITH
THE WARM FRONT. SNOW SHOULD FALL FOR NO LONGER THAN AN HOUR AT
EACH TERMINAL BUT LEFT A 2 HOUR WINDOW IN THE TAFS. STILL NOT SURE
ABOUT THE EXACT TIMING...HENCE THE WINDOW. IFR VSBY STILL LOOKS
REASONABLE ESPECIALLY SINCE MOST SITES UPSTREAM ARE NO LOWER THAN
1 SM. CIGS WILL LOWER TO MVFR WITH THE SNOW AND THEN REMAIN THERE
OVERNIGHT.
STILL DID NOT INCLUDE ANY FREEZING DRIZZLE THIS EVENING AS
CONDITIONS ARE NOT IDEAL. HOWEVER WILL CONTINUE TO MENTION IT HERE
AS FREEZING DRIZZLE WILL LIKELY BE A NUISANCE TO OPERATIONS. IF WE
SEE ANY FREEZING DRIZZLE IT WOULD LIKELY BE BETWEEN 02Z AND 08Z.
OTHERWISE CONDITIONS IMPROVE FRIDAY MORNING TO VFR.
JEE
//ORD AND MDW CONFIDENCE...UPDATED 12Z...
* MEDIUM-LOW CONFIDENCE IN EXACT TIMING OF SNOW SQUALL THIS AFTN
AND HOW LOW VSBYS WILL DROP...BUT HIGH CONFIDENCE IT SHOULD ONLY
LAST FOR AN HOUR OR TWO.
* HIGH CONFIDENCE IN ALL OTHER FORECAST ELEMENTS.
JEE
//OUTLOOK FOR ORD/MDW FOR 00Z SATURDAY-12Z THURSDAY...UPDATED 12Z...
FRIDAY NIGHT...VFR.
SATURDAY...SNOW IN THE AFTN AND EVENING...IFR LIKELY.
SUNDAY...CHC OF FREEZING RAIN OR ICE PELLETS OVERNIGHT. VFR BCMG
MVFR OR LOWER OVERNIGHT.
MONDAY...RAIN OR FREEZING RAIN IN THE MORNING BCMG RAIN OR SNOW IN
THE AFTN. DRY OVERNIGHT. IFR IMPROVING VFR OVERNIGHT.
TUESDAY...VFR.
WEDNESDAY...CHC OF RAIN. VFR BCMG MVFR OR LOWER.
JEE
&&
.MARINE...
318 AM CST
THE SURFACE RIDGE AXIS IS QUICKLY SHIFTING EAST BUT HAVE LIGHT SOUTH
WINDS. LOW PRESSURE IS OVER THE NORTHERN PLAINS AND SOUTH WINDS WILL
INCREASE TO 30 KT TODAY. THE LOW PASSES OVER THE LAKE THIS EVENING
AND WINDS VEER TO NW AT 30 KT BY FRIDAY MORNING. NW WINDS GRADUALLY
DIMINISH THROUGH FRIDAY NIGHT. A RIDGE OF HIGH PRESSURE PASSES OVER
THE LAKE SATURDAY AND WINDS WILL BE LIGHT ACROSS THE LAKE. THE NEXT
LOW PASSES WELL SOUTH OF THE LAKE AND REACHES THE WESTERN OHIO
VALLEY SATURDAY NIGHT. WINDS REMAIN LIGHT WITH DIRECTIONS VARYING
FROM EAST TO NORTHEAST. HIGH PRESSURE THEN SPREADS OVER THE LAKE
SUNDAY. WINDS TURN SE AND INCREASE IN SPEED AHEAD OF THE NEXT LOW
SUNDAY NIGHT. BY MONDAY MORNING WINDS WILL SE TO S TO 30 KT AND
THEN VEER TO WEST 10-20 KT MONDAY NIGHT BEHIND THE LOW. THE
REMAINDER OF EARLY NEXT WEEK LOOKS QUIET OVER THE LAKE.
JEE
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...NONE.
&&
$$
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Area Forecast Discussion
National Weather Service Lincoln IL
530 AM CST Thu Feb 13 2014
.DISCUSSION...
ISSUED 320 AM CST Thu Feb 13 2014
Weather map getting increasingly complicated as the weather
shifts into a more active pattern. Deep wave crossing the srn tier
of the country and another small system moving across the nrn
plains this morning...both of these systems will start the more
active pattern. Though these two storm systems will not directly
impact the CWA, the systems that move into the wake of the more
amplified pattern aloft will bring a couple shots for snow going
into the weekend. Models showing some more consistency btwn
systems through the medium range forecast...if lacking in the
extended. Major warming trend through the forecast creating quite
the spread in the MOS as well. For now, the forecast remains
a conservative blend as the airmass begins to modify.
SHORT TERM...Today and tomorrow...
Partly cloudy skies today not enough to block some significant
warming as winds come around to the south and increasing
throughout the day as the high pressure ridge moves out to the
east. Temperatures will briefly climb above freezing today in most
locations. However, the temp increase will be brief and truncated
by another system for tomorrow. A quick short wave rippling down
from the nrn plains and into the Midwest bringing a shot of snow
to the FA, focusing more to the SW at this point, resulting in an
inch or two for areas southwest of a line from Lincoln to Decatur
to Mattoon. Last model runs slowed down the approach for this
storm, as a result have backed off the pops slightly for late
tonight into the early morning hours, but still should see the
precip developing to the west/southwest after midnight tonight.
Snow will diminish tomorrow evening.
LONG TERM...Saturday through Wednesday...
Another quick wave dives into the Midwest, bringing the best lift
to the NErn portion of the CWA...with another similar inch or two
along and northeast of a line from Galesburg to Champaign.
Temperatures on Sunday will struggle to climb towards freezing,
and the early morning temps will be in the 20s after
midnight/Monday morning. Precipitation spreading ahead of a larger
developing system in the early hours of Monday morning will fall
through a deep mid level warm layer has pushed the forecast to
freezing rain. Available moisture will have to work through some
dry air at first, keeping qpf low...as well as probability at this
point, but the threat for fzra remains that morning. As the temp
rises, and the precip continues to develop with the stronger lift
of the main wave...should go to all rain for Monday while the
temperatures are progged to climb into the 40s. Forecast still
optimistic though there will be a lot of snow to melt...as the
southerly winds will def assist the thaw. Temperatures even warmer
after a cooler day on Tues behind the precip...with AllBlend
pushing the maxT on Wednesday to 40s and 50s.
&&
.AVIATION...
ISSUED 525 AM CST Thu Feb 13 2014
Main forecast concern will be with MVFR cigs west of the Mississippi
River early this morning and how far east they will track this morning
into our area, and then with the timing of snow into central Illinois
late in this forecast period.
Weather system tracking well to our north will take most of the
snow and rain to the north of our forecast area as well. However,
a band of MVFR cigs was noted on satellite data over east central
Iowa and was tracking east. Latest short term forecasts off the
HRRR and WRF ensembles suggest a decrease in coverage expected this
morning as it encounters a very dry air mass over our area as high
pressure is slow to depart. Models have trended back on the coverage
of the MVFR and in some cases pockets of IFR cigs late this morning
into the afternoon hours. Still a concern for PIA and BMI so will
keep at least a scattered to broken MVFR cig in those locations while
scaling back the amount of low cloud cover further south.
The next system will be racing southeast into the Plains states this
evening and will begin to affect SPI after 09z. Based on forecast
sounding data, have opted to leave out of this set of TAFs as the low
level dry air ahead of the storm will tend to delay the onset of the
precip late tonight. Surface winds will become south to southwest
today at 10 to 15 kts with gusts up to 20-24kts by afternoon most
areas. We should see the gusts gradually diminish towards 00z with
directions veering more into a westerly component early this evening.
Smith
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
Area Forecast Discussion
National Weather Service Lincoln IL
350 AM CST Thu Feb 13 2014
.DISCUSSION...
ISSUED 320 AM CST Thu Feb 13 2014
Weather map getting increasingly complicated as the weather
shifts into a more active pattern. Deep wave crossing the srn tier
of the country and another small system moving across the nrn
plains this morning...both of these systems will start the more
active pattern. Though these two storm systems will not directly
impact the CWA, the systems that move into the wake of the more
amplified pattern aloft will bring a couple shots for snow going
into the weekend. Models showing some more consistency btwn
systems through the medium range forecast...if lacking in the
extended. Major warming trend through the forecast creating quite
the spread in the MOS as well. For now, the forecast remains
a conservative blend as the airmass begins to modify.
SHORT TERM...Today and tomorrow...
Partly cloudy skies today not enough to block some significant
warming as winds come around to the south and increasing
throughout the day as the high pressure ridge moves out to the
east. Temperatures will briefly climb above freezing today in most
locations. However, the temp increase will be brief and truncated
by another system for tomorrow. A quick short wave rippling down
from the nrn plains and into the Midwest bringing a shot of snow
to the FA, focusing more to the SW at this point, resulting in an
inch or two for areas southwest of a line from Lincoln to Decatur
to Mattoon. Last model runs slowed down the approach for this
storm, as a result have backed off the pops slightly for late
tonight into the early morning hours, but still should see the
precip developing to the west/southwest after midnight tonight.
Snow will diminish tomorrow evening.
LONG TERM...Saturday through Wednesday...
Another quick wave dives into the Midwest, bringing the best lift
to the NErn portion of the CWA...with another similar inch or two
along and northeast of a line from Galesburg to Champaign.
Temperatures on Sunday will struggle to climb towards freezing,
and the early morning temps will be in the 20s after
midnight/Monday morning. Precipitation spreading ahead of a larger
developing system in the early hours of Monday morning will fall
through a deep mid level warm layer has pushed the forecast to
freezing rain. Available moisture will have to work through some
dry air at first, keeping qpf low...as well as probability at this
point, but the threat for fzra remains that morning. As the temp
rises, and the precip continues to develop with the stronger lift
of the main wave...should go to all rain for Monday while the
temperatures are progged to climb into the 40s. Forecast still
optimistic though there will be a lot of snow to melt...as the
southerly winds will def assist the thaw. Temperatures even warmer
after a cooler day on Tues behind the precip...with AllBlend
pushing the maxT on Wednesday to 40s and 50s.
HJS
&&
.AVIATION...
ISSUED 1156 PM CST Wed Feb 12 2014
An area of VFR clouds at 3.5k-4k feet will move across north-
central IL the rest of the night. It will scape across areas just
north of PIA, based on satellite and forecast soundings. We did
not include a cloud ceiling at any terminal site until 700mb/10k
FT moisture arrives around mid-day on Thursday. Otherwise, mainly
cirrus clouds are expected over the first 12 hours of the TAF
period.
A very weak pressure gradient under departing high pressure will
keep winds light and variable until later Thursday morning. Then
as the clipper and cold front approach from the northwest, winds
will become south and eventually southwest before increasing to
15G25kt at times. Thurs evening winds should continue to veer
around to the west and diminish to around 10-12kt.
The HRRR and 00z NAM project and increase in low level moisture
later Thur into Thur eve, with potential for IFR cloud ceilings
for a time. It appears that PIA and BMI will have the better
chances of IFR conditions, with MVFR possible at the other
terminal sites. Confidence is marginal on how long those clouds
will linger, if they develop at all, since the GFS is not as
aggressive with that moisture.
Shimon
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
321 AM CST THU FEB 13 2014
.DISCUSSION...
757 PM CST
FORECAST PRETTY MUCH ON TRACK THIS EVENING. HAVE MADE A FEW
ADJUSTMENTS TO HOURLY TEMP TRENDS AND CLOUD COVER HOWEVER. TEMPS
HAVE REMAINED FAIRLY STEADY OVER THE LAST FEW HOURS THANKS TO
ABUNDANT CLOUD COVER OVER MUCH OF THE AREA...WITH AN INCREASE OVER
SOUTHERN AREAS ALLOWING TEMPS TO REBOUND A FEW DEGREES. CURRENT
CLOUD COVER...ESPECIALLY OVER THE SOUTHERN CWA...WITH BE BREAKING
UP/MOVING OFF TO THE EAST SO COOLING WILL COMMENCE LATER THIS
EVENING. A RIBBON OF LOWER CLOUD COVER ACROSS THE NORTHERN CWA MAY
STICK AROUND LONGER...WITH SOME HIGH CLOUD COVER ENCROACHING LATER
TONIGHT AS WELL...SO NORTHERN AREAS WILL SEE THE WARMEST TEMPS
OVERNIGHT. FAR SOUTHERN AREAS HOWEVER WILL LIKELY COOL INTO THE
LOWER SINGLE DIGITS...WITH SOME SPOTS POSSIBLY COOLING A LITTLE
MORE THAN FORECAST THANKS TO THE LIGHT WINDS AND DECREASED CLOUD
COVER.
MDB
//PREV DISCUSSION...
320 PM CST
PRIMARY FORECAST CONCERNS ARE WITH THE POTENTIAL MINOR TO MODERATE
SNOW EVENT ON SATURDAY AND THEN MESSY WEATHER POSSIBLE EARLY NEXT
WEEK. BEYOND DAY 7...CONFIDENCE IS STARTING TO INCREASE IN A BRIEF
BUT SIGNIFICANT WARM-UP. ATTENTION WAS ALSO PAID TO A SYSTEM THAT
WILL SKIRT OUR SOUTHERN COUNTIES ON FRIDAY...AS WELL AS A CLIPPER
SYSTEM PASSING TO THE NORTH ON THURSDAY.
TONIGHT...
WEAK RIDGING WILL BE IN PLACE DURING THE EVENING...WITH GRADIENT
INCREASING SOME AS CLIPPER APPROACHES THE REGION TOWARD MORNING.
SOUTHERLY WINDS WILL REMAIN LIGHTEST ALL NIGHT IN SOUTHEASTERN
PORTION OF CWA...WHICH IS WHERE CLOUD COVER IS EXPECTED TO ERODE. AS
A RESULT...DESPITE CONTINUED WARM ADVECTION ALOFT...CONCERNED FOR
READINGS IN THE LOW TO MID POSITIVE SINGLE DIGITS IN THE
SOUTHEAST...WITH A SHOT AT A FEW ISOLATED SUBZERO READINGS IN RURAL
AREAS. OVER NORTHERN ILLINOIS...DID NOT MAKE BIG CHANGES TO GOING
FORECAST LOWS...WITH UPPER SINGLE DIGITS TO LOW TEENS AND MID TEENS
IN DOWNTOWN CHICAGO.
THURSDAY AND THURSDAY NIGHT...
WE WILL BE WELL SOUTH OF A CLIPPER TRACKING ACROSS
WISCONSIN...WHICH IS NOT A FAVORABLE LOCATION FOR APPRECIABLE
PRECIPITATION TYPICALLY. HOWEVER...GLOBAL GUIDANCE CONTINUES TO
PAINT LIGHT QPF NORTH OF I-80 FROM THE LATE MORNING INTO EARLY
AFTERNOON WITH THE NORTH SOUTH WARM FRONT OF THE CLIPPER. BROUGHT
SLIGHT POPS A BIT FARTHER SOUTH...WITH LOW CHANCE ALONG WI BORDER.
CONFIDENCE IN SEEING MEASURABLE SNOW HOWEVER IS LOW. WOULDNT
EXPECT MORE THAN A DUSTING IF IT OCCUR ED. THIS IS ALSO BECAUSE
GUSTING SOUTH- SOUTHWEST WINDS AND WAA ALOFT WILL FINALLY GIVE
MUCH OF THE AREA A CHANCE TO REACH OR EXCEED THE FREEZING MARK FOR
THE FIRST TIME IN 2 WEEKS! A COLDER MODIFIED ARCTIC AIR MASS WILL
THEN FILTER INTO THE AREA BEHIND THE CLIPPER THURSDAY
NIGHT...THOUGH CLOUDS WILL LIKELY LIMIT HOW FAR TEMPERATURES DROP.
EXPECTING LOW-MID TEENS NORTH AND UPPER TEENS TO AROUND 20 SOUTH
OF I-80.
FRIDAY...
ENERGY IN FAST PACIFIC JET BARGING INTO PAC NW THAT HAS NOT YET BEEN
SAMPLED WILL TOP A TEMPORARILY AMPLIFIED MID LEVEL RIDGE OVER THE
INTERMOUNTAIN WEST AND THEN SPEED SOUTHEAST TOWARD THE MID MS
VALLEY. THIS WILL SPUR LOW PRESSURE DEVELOPMENT THAT AT THIS TIME
LOOKS TO GIVE A GLANCING BLOW TO THE SOUTHERN CWA. GIVEN THAT THIS
FEATURE HAS NOT BEEN RAOB SAMPLED YET...CAN STILL FORESEE
ADJUSTMENTS IN THE TRACK...BUT WITH GUIDANCE CONSISTENT ON ONLY A
GLANCING BLOW...KEPT CHANCE POPS CONFINED TO SOUTHERN CWA...WITH
SLIGHT CHANCES UP TO I-80. MAY NEED TO BUMP POPS UP TO LIKELY FOR
FAR SOUTH PENDING FUTURE TRENDS...WITH MINOR ACCUMULATIONS POSSIBLE.
FRIDAY NIGHT...
FAIRLY WEAK GRADIENT WILL BE IN PLACE WITH WEAK RIDGING OVER LOWER
AND MID MS VALLEY. THUS WINDS SHOULD BE LIGHT AND EXPECTING AT MOST
PARTLY CLOUDY SKIES UNTIL SOME INCREASE FROM NORTHWEST IN ADVANCE OF
NEXT CLIPPER TOWARDS DAYBREAK. GIVEN HOW COLD PAST FEW NIGHTS WERE
WITH SIMILAR OR WARMER TEMP PROFILE THAN INDICATED FRIDAY
NIGHT...AND DEEP SNOWPACK IN PLACE...HAVE LOWERED AREAS WEST OF FOX
VALLEY TO THE MINUS SINGLE DIGITS AND CONCERNED THAT THESE ARE TOO
MILD. DEPENDING ON CLOUD COVER FARTHER SOUTH AND EAST...MAY ALSO
NEED TO LOWER TEMPS MORE AWAY FROM DOWNTOWN CHICAGO.
SATURDAY...
OPERATIONAL GUIDANCE STILL DIFFERS SOME ON TRACK AND A BIT ON TIMING
OF AFOREMENTIONED CLIPPER...HOWEVER GFS ENSEMBLES ARE IN FAIRLY
DECENT AGREEMENT. SUBTLE FEATURES LIKE CLIPPERS ARE PRONE TO
RELATIVELY SIGNIFICANT CHANGES IN TRACK BEFORE ADEQUATE SAMPLING BUT
THERE IS SOLID ENOUGH CONSENSUS IN ACCUMULATING SNOW OVER THE AREA
THAT I FELT COMFORTABLE IN INCREASING POPS FOR MOST OF THE CWA TO
LIKELY DURING THE DAY ON SATURDAY...WITH LIKELY POPS FOCUSED TO THE
EAST AND SOUTHEAST ON SATURDAY EVENING AS THE CLIPPER DEPARTS. SIGNS
THAT THE WAVE THAT WILL PRODUCE THE CLIPPER WILL DAMPEN SOME AS IT
TRAVERSES THE REGION...SO ITS POSSIBLE DAYTIME SATURDAY WILL END UP
BEING MOST FAVORED FOR ACCUMS. FORECAST SOUNDINGS SHOWING A
RELATIVELY DEEP/ABOUT 100 MB/DGZ...SO COULD SEE RATIOS A BIT HIGHER
THAN AVERAGE. AT THIS TIME...THE THINKING IS A 1-3" OR PERHAPS UP TO
2-4" TYPE SNOWFALL.
SUNDAY THROUGH WEDNESDAY AND BEYOND...
SUNDAY WILL BE A QUIET AND SLIGHTLY BELOW NORMAL DAY UNDER HIGH
PRESSURE OVER THE WESTERN LAKES. CHANGES WILL TAKE PLACE SUNDAY
NIGHT...AS MIDLEVEL RIDGING WILL ENSUE IN RESPONSE TO A DEEPENING
TROUGH AND CYCLONE OVER THE SOUTHERN PLAINS. LOW LEVEL JET WILL
RESULT IN RAPID WARMING ALOFT TO 2 TO 5 C AT 850 MB BY DAYBREAK
MONDAY. SHOULD PRECIPITATION BREAK OUT OVERNIGHT SUNDAY
NIGHT...SURFACE TEMPERATURES WILL LIKELY STILL BE WELL BELOW
FREEZING TO START BUT WITH WARM SURGE ALOFT...INDICATED SLIGHT TO
LOW CHANCES FOR SLEET/ZR. TOO EARLY FOR SPECIFIC DETAILS ON MONDAY
BUT LOW PRESSURE LOOKS TO MOVE NEAR OR OVER THE AREA ON
MONDAY...WITH COLDER AIR RETURNING BEHIND IT LATE IN THE DAY INTO
MONDAY NIGHT. IT APPEARS PRETTY TO BE A DECENT BET FOR THE ENTIRE
CWA TO WARM ABOVE FREEZING DURING THE DAY...PROBABLY EARLIEST IN
THE SOUTH...BUT WITH VERY COLD GROUND TEMPS CONCERNED THAT THERE
STILL COULD BE ICING. PRECIP SHOULD THEN TRANSITION BACK TO SNOW
BY MONDAY EVENING COLUMN COOLS...WITH ANY IMPACTS DICTATED BY HOW
PROGRESSIVE THE LOW PRESSURE AREA IS. TRANSITION DAY FOR
SIGNIFICANT BUT BRIEF PATTERN CHANGE THAT IS BECOMING MORE LIKELY
WILL BE TUESDAY. ON WEDNESDAY...RAPID HEIGHT RISES AND WAA IN
RESPONSE TO DEEPENING TROUGH OVER THE WEST WILL RESULT IN
TEMPERATURES WARMING TO AT LEAST 40 AREA WIDE IN ALL LIKELIHOOD.
BECOMING QUITE CONCERNED WITH WHAT THE OPERATIONAL MODELS ARE
SHOWING WEDNESDAY NIGHT THROUGH FRIDAY NEXT WEEK...WITH H8 TEMPS
WARMING TO +10C OR HIGHER A STRONG LOW LEVEL JET FROM A WIDE OPEN
GULF AND SURFACE SOUTHERLY FLOW PUMPING IN A MOIST AND UNSEASONABLY
MILD AIR MASS. POTENTIAL EXISTS FOR 50S AND 60S ON THURS-FRI...AND
IF THIS OCCURS...RAPID SNOWMELT OF DEEP SNOWPACK CONTAINING 1-4" OF
WATER AND ICE MELT ON RIVERS WOULD ENSUE...WITH ASSOCIATED FLOODING
CONCERNS. THIS WOULD BE EXACERBATED BY ANY PERIODS OF STEADY
RAINFALL. WE WILL BE WATCHING THIS PERIOD VERY CLOSELY IN THE
COMING DAYS. COLDER AIR THEN LOOKS TO RETURN NEXT WEEKEND.
RC
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 09Z...
* SOUTH WINDS GUSTING TO 20 KT BCMG WEST THIS EVENING AND GUSTING
UP TO 25 KT FROM MID AFTERNOON ONWARD.
* POTENTIAL FOR A SHORT 1 TO 2 HOUR PERIOD OF SNOW EARLY THIS
AFTN...WITH A SHORT PERIOD OF IFR TO LIFR VSBY PSBL.
* MVFR CIGS ACCOMPANY THE SNOW AND LINGER OVERNIGHT.
JEE
//DISCUSSION...UPDATED 06Z...
A HIGH PRESSURE RIDGE IS OVERHEAD AND A HIGH END MVFR/LOW END VFR
CLOUD DECK REMAINS OVER THE REGION. THE CLOUDS SHOW NO SIGN OF
BREAKING UP AND SHORT TERM GUIDANCE INDICATES THE MASS OF CLOUDS
SHOULD REMAIN OVERHEAD THROUGH THIS MORNING. WITH THICK CLOUD
COVER OVERHEAD...THINKING FOG WILL NOT DEVELOP AT DPA.
LOW PRESSURE PASSES OVER NORTHERN WI TODAY AND THERE STILL IS
CONCERN THAT A BRIEF BUT INTENSE SNOW SQUALL COULD IMPACT THE
TERMINALS THIS AFTERNOON. BUT BEFORE THAT...SOUTH WINDS PICK UP BY
MID MORNING AND BEGIN GUSTING TO 20 KT. THE SNOW SQUALL WOULD BE
EXPECTED EARLY THIS AFTN AND ONLY LAST AN HOUR OR TWO AT THE
TERMINALS. HOWEVER CANNOT NAIL DOWN A SPECIFIC TIME JUST YET SO
LEFT THE PROB30 IN THE TAFS FOR EARLY THIS AFTN. ALSO NOT SURE HOW
INTENSE THE SNOW WILL BE BUT IFR IF NOT LOWER VSBY SEEMS VERY REASONABLE.
CIGS LOWER TO MVFR WITH THE SNOW AND REMAIN THERE THROUGH THE
REST OF THE TAF PERIOD. WINDS ALSO INCREASE IN THE AFTN WITH SW
WINDS GUSTING TO 25 KT. WINDS BECOME WEST BEHIND THE LOWS COLD
FRONT AND CONTINUE TO GUST TO ARND 25 KT THROUGH THE LATE EVENING.
THE W TO NW WINDS REMAIN GUSTY BUT ONLY TO 20 KT AFTER MIDNIGHT.
AM A BIT CONCERNED THAT THERE MAY BE A STRAY FLURRY OR PERIOD OF
FREEZING DRIZZLE LATE THIS EVENING AS WELL...BUT DO NOT HAVE
ENOUGH CONFIDENCE TO PUT IT IN THE TAF JUST YET. IF THE PRECIP
DOES FORM...EXPECTING IT IN THE 00-05Z TIME FRAME AT RFD AND BTWN
03Z AND 09Z AT THE EASTERN TERMINALS.
JEE
//ORD AND MDW CONFIDENCE...UPDATED 09Z...
* MEDIUM-LOW CONFIDENCE IN EXACT TIMING OF SNOW SQUALL THIS AFTN
AND HOW LOW VSBYS WILL DROP...BUT HIGH CONFIDENCE IT SHOULD ONLY
LAST FOR AN HOUR OR TWO.
* HIGH CONFIDENCE IN ALL OTHER FORECAST ELEMENTS.
JEE
//OUTLOOK FOR ORD/MDW FOR 12Z FRIDAY-12Z WEDNESDAY...UPDATED 00Z...
FRIDAY...VFR.
SATURDAY...SNOW IN THE AFTERNOON AND EVENING...WITH IFR CONDITIONS.
SUNDAY...MAINLY VFR DURING THE DAY. A SLIGHT CHC OF A WINTER MIX
LATE SUNDAY NIGHT WITH MVFR PSBL.
MONDAY...CHC RA OR FZRA DURING THE DAY...POSSIBLY ENDING AS SNOW
OVERNIGHT. IFR OR LOWER POSSIBLE.
TUESDAY...VFR.
KJB
&&
.MARINE...
318 AM CST
THE SURFACE RIDGE AXIS IS QUICKLY SHIFTING EAST BUT HAVE LIGHT SOUTH
WINDS. LOW PRESSURE IS OVER THE NORTHERN PLAINS AND SOUTH WINDS WILL
INCREASE TO 30 KT TODAY. THE LOW PASSES OVER THE LAKE THIS EVENING
AND WINDS VEER TO NW AT 30 KT BY FRIDAY MORNING. NW WINDS GRADUALLY
DIMINISH THROUGH FRIDAY NIGHT. A RIDGE OF HIGH PRESSURE PASSES OVER
THE LAKE SATURDAY AND WINDS WILL BE LIGHT ACROSS THE LAKE. THE NEXT
LOW PASSES WELL SOUTH OF THE LAKE AND REACHES THE WESTERN OHIO
VALLEY SATURDAY NIGHT. WINDS REMAIN LIGHT WITH DIRECTIONS VARYING
FROM EAST TO NORTHEAST. HIGH PRESSURE THEN SPREADS OVER THE LAKE
SUNDAY. WINDS TURN SE AND INCREASE IN SPEED AHEAD OF THE NEXT LOW
SUNDAY NIGHT. BY MONDAY MORNING WINDS WILL SE TO S TO 30 KT AND
THEN VEER TO WEST 10-20 KT MONDAY NIGHT BEHIND THE LOW. THE
REMAINDER OF EARLY NEXT WEEK LOOKS QUIET OVER THE LAKE.
JEE
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...NONE.
&&
$$
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Area Forecast Discussion
National Weather Service Lincoln IL
1156 PM CST Wed Feb 12 2014
.DISCUSSION...
ISSUED 900 PM CST Wed Feb 12 2014
A band of mid clouds at 9k ft moved across our northern counties
over the last couple of hours. Some radar returns coincided with
their passage over Peoria and Bloomington, but no precipitation
reached the ground due to the very dry air below the clouds. Those
clouds have mostly dissipated as of 855 pm as they moved into the
surface ridge. Additional clouds farther west across eastern Iowa
are remaining relatively stationary as the associated cold frontal
boundary dissipates.
We are still expecting a brief period of colder air as the
remnants of the cold front/trough pass across northern IL tonight,
but the cool down will be brief as warmer air immediately begins a
return ahead of the next clipper system. Highs should rebound into
the mid to upper 30s for highs, after morning lows in the single
digits to around 10 above. A cold front with that system is
projected to reach near the Illinois river by 6pm Thursday, but
light snow should remain north of our counties. A better chance of
measurable snow will come with yet another shortwave disturbance
affecting our southwest counties Friday. Areas southwest of a line
from Rushville to Lincoln to Mattoon could see 1 to 3 inches of
snow, with the higher amounts farther southwest of Jacksonville to
Springfield to Effingham.
Updates tonight were mainly to the sky grids to slow down the
arrival of clouds and some minor adjustments to lower the low
temps in a few spots that dropped off quickly this evening.
Updated forecast info will be available shortly.
Shimon
&&
.AVIATION...
ISSUED 1156 PM CST Wed Feb 12 2014
An area of VFR clouds at 3.5k-4k feet will move across north-
central IL the rest of the night. It will scape across areas just
north of PIA, based on satellite and forecast soundings. We did
not include a cloud ceiling at any terminal site until 700mb/10k
FT moisture arrives around mid-day on Thursday. Otherwise, mainly
cirrus clouds are expected over the first 12 hours of the TAF
period.
A very weak pressure gradient under departing high pressure will
keep winds light and variable until later Thursday morning. Then
as the clipper and cold front approach from the northwest, winds
will become south and eventually southwest before increasing to
15G25kt at times. Thurs evening winds should continue to veer
around to the west and diminish to around 10-12kt.
The HRRR and 00z NAM project and increase in low level moisture
later Thur into Thur eve, with potential for IFR cloud ceilings
for a time. It appears that PIA and BMI will have the better
chances of IFR conditions, with MVFR possible at the other
terminal sites. Confidence is marginal on how long those clouds
will linger, if they develop at all, since the GFS is not as
aggressive with that moisture.
Shimon
&&
.PREV DISCUSSION...
ISSUED 300 PM CST Wed Feb 12 2014
Active weather pattern will bring a couple chances for light snow
over the next few days...followed by a major warming trend next week.
SHORT TERM...Tonight through Saturday
Vigorous short-wave noted on latest water vapor imagery near
Kansas City will continue to dive southeastward tonight, carving
out a significant trough over the Deep South. Strongest lift
associated with this feature will remain S/SW of Illinois this
evening, thus chances for any very light precip are dwindling.
Radar mosaic has been showing light snow across Iowa/northern
Missouri steadily diminishing this afternoon as upper support
wanes and precip moves toward a drier airmass east of the
Mississippi River. Due to these trends, have removed chance for
flurries during the evening hours. While skies will start out
partly to mostly cloudy, mostly clear conditions will return
overnight. Due to the clearing skies and continued very light
winds, am expecting another cold night with lows in the single
digits above zero.
Next upstream short-wave currently over the Northern Rockies will
remain to the north of central Illinois on Thursday, with any snow
confined to Wisconsin and perhaps far northern Illinois. Further
south, partly sunny skies and an increasing southwesterly wind
will help boost temps above the freezing mark. Numeric guidance
shows quite a temp spread for Thursday, with the MET being about
5 degrees colder than the MAV. Based on what is currently
happening across central Illinois where sunshine and light winds
have already resulted in temps rebounding well into the 20s, will
lean toward the warmer guidance tomorrow when WAA will be much
stronger. As a result, highs will reach the middle to upper 30s
across the board.
Once the Thursday system skirts by to the north, attention will
turn to yet another short-wave expected to race through the region
late Thursday night into Friday. 12z Feb 12 models have shifted
the 500mb vort max track a bit further south than previous
runs...now more closely resembling the GEM from the past few days.
Track from the Dakotas Thursday evening to the lower Ohio River
Valley by Friday evening places the southern half of the KILX CWA
in a favorable zone for accumulating snow. System will have
adequate upper support and a decent amount of moisture to work
with, but will be moving quickly. Based on expected QPF, think 1
to 2 inches of snow will fall along and southwest of a
Rushville...to Springfield...to Robinson line late Thursday night
into Friday morning. Further northeast, little or no accumulation is
anticipated along and north of I-74.
Next in the series of fast-moving storm system moves into the
region on Saturday, with all operational models agreeing on a
further north track than the Friday system. Similar dynamics and
moisture profiles in play will produce 1 to 2 inches of snow
across the northern KILX CWA, mainly along/north of I-74 on
Saturday. Further southwest, only trace amounts are expected
across the S/SW CWA around Jacksonville and Springfield.
LONG TERM...Sunday through Wednesday
Active weather pattern continues into the extended, as
southwesterly upper flow develops across much of the central and
eastern CONUS next week. As next storm system approaches, warmer
air will override the cold airmass in place...potentially
producing some wintry precipitation Sunday night. Forecast
soundings do not fully saturate: however, all are warm enough to
support liquid precip. The problem will be surface temps, which
are expected to be below freezing. Therefore if any precip arrives
late Sunday night, it will be in the form of freezing rain. At
this point, am not totally convinced precip will arrive that soon,
so will only carry slight chance POPs for freezing rain. Much
better precip chances arrive on Monday as system moves in from the
southwest. Temps will be warm enough to support rain, with highs
reaching the lower to middle 40s. Once this system exits, upper
heights will continue to rise...resulting in a marked warming
trend for the middle and end of next week. While raw model data
suggests highs potentially reaching the 60s by next
Thursday/Friday, lingering snow cover will likely mitigate the
warming. Even still, temps climbing above the 50 degree mark seem
quite plausible.
Barnes
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS GRAY ME
1236 PM EST THU FEB 13 2014
.SYNOPSIS...
LOW PRESSURE WILL TRACK UP THE EAST COAST AND TOWARD CAPE COD
TODAY. SNOW WILL SPREAD NORTHWARD IN ADVANCE OF THE LOW. THE SNOW
WILL MIX WITH OR CHANGE TO SLEET AND FREEZING RAIN...ESPECIALLY
OVER COASTAL AND EASTERN AREAS TONIGHT BEFORE CHANGING BACK TO
SNOW AGAIN FRIDAY MORNING. THE STORM SYSTEM WITH THEN EXIT INTO
THE MARITIMES BY FRIDAY NIGHT. A SECOND LOW PRESSURE SYSTEM MOVES
BY...TRACKING FURTHER OUT TO SEA...ON SATURDAY. THIS SECOND LOW
THEN INTENSIFIES AS IT MOVES INTO THE MARITIMES SATURDAY NIGHT
DRAWING MORE COLD AIR INTO NEW ENGLAND ON GUSTY NORTHWEST WINDS.
HIGH PRESSURE BUILDS IN SUNDAY AND SUNDAY NIGHT BEFORE MOVING
OFFSHORE MONDAY. ANOTHER LOW PRESSURE SYSTEM MOVES IN FOR MONDAY
AND TUESDAY...PERHAPS BRINGING MIXED PRECIPITATION TO THE REGION.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
1225 PM...CURRENT FORECAST IS IN GOOD SHAPE I MADE ONLY MINOR
ADJUSTMENTS TO 1ST PERIOD GRIDS FOR THIS ESTF UPDATE TO REFLECT
MESONET TRENDS. I UPGRADED THE WATERS FOR A PERIOD OF STORM FORCE
GUSTS TONIGHT OUTSIDE TO THE BAYS.
905 AM...AT 14Z A 996 MILLIBAR LOW WAS VICNITY OF THE DELMARVA
WITH 3 HOUR PRESSURE FALLS ALONG THE MID ATLANTIC COAST
APPROACHING 8 MILLIBARS. SNOW WAS EXPANDING NORTHWARD INTO
SOUTHERN SECTIONS OF THE FORECAST AREA AND SHOULD QUICKLY
OVERSPREAD THE REMAINDER OF THE REGION BY EARLY AFTERNOON. I MADE
MINOR ADJUSTMENTS TO 1ST PERIOD GRIDS FOR THIS ESTF UPDATE TO
REFLECT THE MESONET AS WELL AS SATELLITE TRENDS.
PREV DISC...
UPDATE...
HAVE UPDATED GRIDS BASED ON CURRENT CONDITIONS. SNOW IS ROCKETING
QUICKLY UP THE COASTLINE AND SHOULD HAVE OVERSPREAD COASTAL YORK
COUNTY BY 8 AM AND IN THE PORTLAND AREA BY 9 AM WHICH IS IN LINE
WITH THE NEW HRRR RUN. HAVE ADJUSTED THE 6 HOUR SNOW GRID HIGHER FOR
SOUTHERN NH AND PORTIONS OF FAR SOUTHWEST MAINE ENDING AT 1
PM...AND THIS MAY NEED TO BE NUDGED UPWARDS FURTHER.
OTHERWISE...COLD AIR REMAINS INTACT THIS MORNING ACROSS THE
FORECAST AREA. A COASTAL FRONT SHOULD BE FORMING
SHORTLY...BRINGING LIGHT SNOWFALL TO THE ENTIRE COASTLINE BY MID MORNING.
PREV DISC...
SNOW CONTINUES TO SPREAD INTO SOUTHERN NEW ENGLAND EARLY THIS
MORNING. THIS PRECIPITATION SHIELD WILL RUN INTO A WALL OF VERY
COLD AND DRY AIR THIS MORNING AS IT ATTEMPT TO ENTER NORTHERN NEW
ENGLAND. NEVERTHELESS...WARM AIR ADVECTION PATTERN AND DEEP
MOISTURE SUPPLY FROM THE GULF OF MEXICO AND THE ATLANTIC WILL
ALLOW FOR THE PRECIPITATION TO QUICKLY OVERCOME THIS DRY COLUMN.
SNOW WILL SPREAD NORTH AND EAST THIS MORNING INTO OUR REGION WHERE
WINTER STORM WARNINGS BEGIN AT 7 AM. THE NAM...AS ALWAYS IS
GANGBUSTERS WITH QPF WHICH APPEARS TO BE OVERDONE (ALTHOUGH THE 4
KM NAM IS VERY IMPRESSIVE THIS MORNING). HOWEVER...THE GFS IS MUCH
DRIER. PREFER THE EURO WHICH IS A GOOD BLEND OF THESE SOLUTIONS.
THIS MODEL SOLUTION BRINGS 5 TO 8 INCHES OF SNOW TODAY AND INTO
THIS EVENING OVER FAR SOUTHERN AREAS. THIS IS IMPORTANT...AS WARM
AIR WILL ENTER THIS REGION DUE TO A DRY SLOT ROTATING IN OVER THE
MID LAYERS OF THE ATMOSPHERE. THIS WILL ALLOW WARM AIR TO ENTER
THE REGION ALOFT...BRINGING SLEET AND FREEZING RAIN TO SOUTHERN
AREAS...AND EFFECTIVELY SHUTTING DOWN THE ACCUMULATING SNOW FOR
MUCH OF THE NIGHT. AT THE SURFACE...TEMPERATURES WILL REMAIN COLD
WITH A NORTH WIND. HAVE THEREFORE REMOVED THE MENTION OF RAIN
ALONG THE COAST AS...AFTER OUR COLD...RADIATIONAL COOLING NIGHT
LAST NIGHT...ALL AREAS ARE RUNNING LOWER TEMPERATURES THAN MOS
SOLUTIONS AT THIS TIME. PLENTY OF DRY AIR AT THE ONSET OF THE
PRECIPITATION WILL ALLOW FOR EVAPORATIONAL COOLING IN THE COLUMN
AS WELL.
FOR REASONS MENTIONED ABOVE...OUR WARM AIR ADVECTION "THUMP" WILL
ALLOW FOR SNOWFALL TOTALS TO JUST REACH INTO THE WARNING CRITERIA
OVER ROCKINGHAM COUNTY AS WELL...THEREFORE THIS COUNTY HAS BEEN
ADDED TO THE WARNINGS.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM FRIDAY/...
972 MB LOW REACHES POINTS JUST EAST OF PORTLAND BY LATE TONIGHT
AND FRIDAY MORNING. THE MOUNTAINS WILL STILL BE HAVING
ACCUMULATING SNOW AT THAT TIME...WHILE WRAP AROUND PRECIPITATION
ATTEMPTS TO REENTER SOUTHERN AREAS. CLIMATOLOGY WOULD SUGGEST
THESE WRAP AROUND BANDS WILL CROSS CENTRAL AREAS...BUT ALSO HAVE A
DIFFICULT TIME REACHING THE COAST.
MOST AREAS WILL MAX OUT IN THE 8 TO 12 INCH RANGE FOR SNOWFALL
WITH THIS LATEST STORM. HOWEVER...THERE WILL BE LOCALLY HIGHER
AMOUNTS IN ANY BANDED PRECIPITATION AND ALSO OVER THE NE FACING
HIGH TERRAIN. LESS SNOW WILL ACCUMULATE NEAR THE COAST.
AROUND A THIRD OF AN INCH OF ICE MAY NOW OCCUR ALONG THE
COAST...WHICH COULD LEAD TO ISOLATED POWER OUTAGES.
&&
.LONG TERM /FRIDAY NIGHT THROUGH WEDNESDAY/...
A WEAK RIDGE OF HIGH PRES MOVES OVER THE REGION FRI NIGHT BUT
QUICKLY GIVES WAY TO AN UPSTREAM TROF THAT WILL BE DIGGING INTO
NEW ENGLAND SATURDAY BRINGING SOME LIGHT SNOW ACROSS THE AREA. THIS
UPPER TROF DEVELOPS A STRONG SFC LOW WELL SOUTHEAST OF CAPE COD,
BUT EXACT PLACEMENT OF THE DVLPG SFC LOW FOR LATE SAT AND INTO
SAT EVNG BY THE MODELS WILL NEED TO BE WATCHED. LATEST EURO
SUGGESTS IT WILL BE A CLOSE CALL WHILE OTHER MODELS ARE FURTHER
EAST. BY LATE SAT NIGHT AND SUN THE TROF EXITS WELL TO THE EAST
AND CLEARING AND COLDER TEMPS RETURN. A LARGE RIDGE OF HIGH PRES
MOVES OVER NEW ENGLAND MONDAY BRINGING WITH IT A NICE DAY. THE NEXT
TROF APPROACHES ON TUES WITH AN ASSOC SFC LO THAT WILL PROBABLY
TRACK ALONG THE ST LAWRENCE VLY BY WITH BRING SOME LGT SNOW ACROSS
THE REGION. MIDWEEK HIGH PRES RETURNS WITH A WARMER SWLY FLOW TO
DVLP LATE IN THE WEEK.
&&
.AVIATION /18Z THURSDAY THROUGH TUESDAY/...
SHORT TERM...VFR CONDITIONS SHOULD DETERIORATE TO IFR AND LIFR
CONDITIONS TODAY AS SNOW SPREADS NORTHWARD. A PERIOD OF SLEET AND
FREEZING RAIN IS POSSIBLE ON THE COASTAL PLAIN THURSDAY NIGHT.
CONDITIONS IMPROVE FRIDAY.
LONG TERM...
MVFR AMD POSSIBLY IFR CONDS IN LIGHT SNOW SAT INTO SAT NIGHT. VFR
SUNDAY INTO MONDAY.
&&
.MARINE...
SHORT TERM...AS LOW PRESSURE MOVES THROUGH THE GULF OF MAINE
EXPECT WINDS TO REACH INTO THE GALE WARNING RANGE. THERE IS A LOW
POSSIBILITY OF STORM FORCE GUSTS OUTSIDE THE BAYS EARLY TONIGHT.
LONG TERM...
SCA CONDS PSBL LATE SAT THRU SUN AND AGAIN MON NIGHT AND TUE.
&&
.GYX WATCHES/WARNINGS/ADVISORIES...
ME...WINTER STORM WARNING UNTIL 9 AM EST FRIDAY FOR MEZ018-019-023-
024.
WINTER STORM WARNING UNTIL NOON EST FRIDAY FOR MEZ007>009-
012>014-020>022-025>028.
NH...WINTER STORM WARNING UNTIL 9 AM EST FRIDAY FOR NHZ003>010-013-
014.
WINTER STORM WARNING UNTIL NOON EST FRIDAY FOR NHZ001-002.
MARINE...GALE WARNING UNTIL 11 AM EST FRIDAY FOR ANZ151-153.
STORM WARNING UNTIL 9 AM EST FRIDAY FOR ANZ150-152-154.
GALE WARNING FROM 9 AM TO 11 AM EST FRIDAY FOR ANZ150-152-154.
&&
$$
ES
AREA FORECAST DISCUSSION
NWS GRAY ME
928 AM EST THU FEB 13 2014
.SYNOPSIS...
LOW PRESSURE WILL TRACK UP THE EAST COAST AND TOWARD CAPE COD
TODAY. SNOW WILL SPREAD NORTHWARD IN ADVANCE OF THE LOW. THE SNOW
WILL MIX WITH OR CHANGE TO SLEET AND FREEZING RAIN...ESPECIALLY
OVER COASTAL AND EASTERN AREAS TONIGHT BEFORE CHANGING BACK TO
SNOW AGAIN FRIDAY MORNING. THE STORM SYSTEM WITH THEN EXIT INTO
THE MARITIMES BY FRIDAY NIGHT. A SECOND LOW PRESSURE SYSTEM MOVES
BY...TRACKING FURTHER OUT TO SEA...ON SATURDAY. THIS SECOND LOW
THEN INTENSIFIES AS IT MOVES INTO THE MARITIMES SATURDAY NIGHT
DRAWING MORE COLD AIR INTO NEW ENGLAND ON GUSTY NORTHWEST WINDS.
HIGH PRESSURE BUILDS IN SUNDAY AND SUNDAY NIGHT BEFORE MOVING
OFFSHORE MONDAY. ANOTHER LOW PRESSURE SYSTEM MOVES IN FOR MONDAY
AND TUESDAY...PERHAPS BRINGING MIXED PRECIPITATION TO THE REGION.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
905 AM...AT 14Z A 996 MILLIBAR LOW WAS VICNITY OF THE DELMARVA
WITH 3 HOUR PRESSURE FALLS ALONG THE MID ATLANTIC COAST
APPROACHING 8 MILLIBARS. SNOW WAS EXPANDING NORTHWARD INTO
SOUTHERN SECTIONS OF THE FORECAST AREA AND SHOULD QUICKLY
OVERSPREAD THE REMAINDER OF THE REGION BY EARLY AFTERNOON. I MADE
MINOR ADJUSTMENTS TO 1ST PERIOD GRIDS FOR THIS ESTF UPDATE TO
REFLECT THE MESONET AS WELL AS SATELLITE TRENDS.
PREV DISC...
UPDATE...
HAVE UPDATED GRIDS BASED ON CURRENT CONDITIONS. SNOW IS ROCKETING
QUICKLY UP THE COASTLINE AND SHOULD HAVE OVERSPREAD COASTAL YORK
COUNTY BY 8 AM AND IN THE PORTLAND AREA BY 9 AM WHICH IS IN LINE
WITH THE NEW HRRR RUN. HAVE ADJUSTED THE 6 HOUR SNOW GRID HIGHER FOR
SOUTHERN NH AND PORTIONS OF FAR SOUTHWEST MAINE ENDING AT 1
PM...AND THIS MAY NEED TO BE NUDGED UPWARDS FURTHER.
OTHERWISE...COLD AIR REMAINS INTACT THIS MORNING ACROSS THE
FORECAST AREA. A COASTAL FRONT SHOULD BE FORMING
SHORTLY...BRINGING LIGHT SNOWFALL TO THE ENTIRE COASTLINE BY MID MORNING.
PREV DISC...
SNOW CONTINUES TO SPREAD INTO SOUTHERN NEW ENGLAND EARLY THIS
MORNING. THIS PRECIPITATION SHIELD WILL RUN INTO A WALL OF VERY
COLD AND DRY AIR THIS MORNING AS IT ATTEMPT TO ENTER NORTHERN NEW
ENGLAND. NEVERTHELESS...WARM AIR ADVECTION PATTERN AND DEEP
MOISTURE SUPPLY FROM THE GULF OF MEXICO AND THE ATLANTIC WILL
ALLOW FOR THE PRECIPITATION TO QUICKLY OVERCOME THIS DRY COLUMN.
SNOW WILL SPREAD NORTH AND EAST THIS MORNING INTO OUR REGION WHERE
WINTER STORM WARNINGS BEGIN AT 7 AM. THE NAM...AS ALWAYS IS
GANGBUSTERS WITH QPF WHICH APPEARS TO BE OVERDONE (ALTHOUGH THE 4
KM NAM IS VERY IMPRESSIVE THIS MORNING). HOWEVER...THE GFS IS MUCH
DRIER. PREFER THE EURO WHICH IS A GOOD BLEND OF THESE SOLUTIONS.
THIS MODEL SOLUTION BRINGS 5 TO 8 INCHES OF SNOW TODAY AND INTO
THIS EVENING OVER FAR SOUTHERN AREAS. THIS IS IMPORTANT...AS WARM
AIR WILL ENTER THIS REGION DUE TO A DRY SLOT ROTATING IN OVER THE
MID LAYERS OF THE ATMOSPHERE. THIS WILL ALLOW WARM AIR TO ENTER
THE REGION ALOFT...BRINGING SLEET AND FREEZING RAIN TO SOUTHERN
AREAS...AND EFFECTIVELY SHUTTING DOWN THE ACCUMULATING SNOW FOR
MUCH OF THE NIGHT. AT THE SURFACE...TEMPERATURES WILL REMAIN COLD
WITH A NORTH WIND. HAVE THEREFORE REMOVED THE MENTION OF RAIN
ALONG THE COAST AS...AFTER OUR COLD...RADIATIONAL COOLING NIGHT
LAST NIGHT...ALL AREAS ARE RUNNING LOWER TEMPERATURES THAN MOS
SOLUTIONS AT THIS TIME. PLENTY OF DRY AIR AT THE ONSET OF THE
PRECIPITATION WILL ALLOW FOR EVAPORATIONAL COOLING IN THE COLUMN
AS WELL.
FOR REASONS MENTIONED ABOVE...OUR WARM AIR ADVECTION "THUMP" WILL
ALLOW FOR SNOWFALL TOTALS TO JUST REACH INTO THE WARNING CRITERIA
OVER ROCKINGHAM COUNTY AS WELL...THEREFORE THIS COUNTY HAS BEEN
ADDED TO THE WARNINGS.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM FRIDAY/...
972 MB LOW REACHES POINTS JUST EAST OF PORTLAND BY LATE TONIGHT
AND FRIDAY MORNING. THE MOUNTAINS WILL STILL BE HAVING
ACCUMULATING SNOW AT THAT TIME...WHILE WRAP AROUND PRECIPITATION
ATTEMPTS TO REENTER SOUTHERN AREAS. CLIMATOLOGY WOULD SUGGEST
THESE WRAP AROUND BANDS WILL CROSS CENTRAL AREAS...BUT ALSO HAVE A
DIFFICULT TIME REACHING THE COAST.
MOST AREAS WILL MAX OUT IN THE 8 TO 12 INCH RANGE FOR SNOWFALL
WITH THIS LATEST STORM. HOWEVER...THERE WILL BE LOCALLY HIGHER
AMOUNTS IN ANY BANDED PRECIPITATION AND ALSO OVER THE NE FACING
HIGH TERRAIN. LESS SNOW WILL ACCUMULATE NEAR THE COAST.
AROUND A THIRD OF AN INCH OF ICE MAY NOW OCCUR ALONG THE
COAST...WHICH COULD LEAD TO ISOLATED POWER OUTAGES.
&&
.LONG TERM /FRIDAY NIGHT THROUGH WEDNESDAY/...
A WEAK RIDGE OF HIGH PRES MOVES OVER THE REGION FRI NIGHT BUT
QUICKLY GIVES WAY TO AN UPSTREAM TROF THAT WILL BE DIGGING INTO
NEW ENGLAND SATURDAY BRINGING SOME LIGHT SNOW ACROSS THE AREA. THIS
UPPER TROF DEVELOPS A STRONG SFC LOW WELL SOUTHEAST OF CAPE COD,
BUT EXACT PLACEMENT OF THE DVLPG SFC LOW FOR LATE SAT AND INTO
SAT EVNG BY THE MODELS WILL NEED TO BE WATCHED. LATEST EURO
SUGGESTS IT WILL BE A CLOSE CALL WHILE OTHER MODELS ARE FURTHER
EAST. BY LATE SAT NIGHT AND SUN THE TROF EXITS WELL TO THE EAST
AND CLEARING AND COLDER TEMPS RETURN. A LARGE RIDGE OF HIGH PRES
MOVES OVER NEW ENGLAND MONDAY BRINGING WITH IT A NICE DAY. THE NEXT
TROF APPROACHES ON TUES WITH AN ASSOC SFC LO THAT WILL PROBABLY
TRACK ALONG THE ST LAWRENCE VLY BY WITH BRING SOME LGT SNOW ACROSS
THE REGION. MIDWEEK HIGH PRES RETURNS WITH A WARMER SWLY FLOW TO
DVLP LATE IN THE WEEK.
&&
.AVIATION /14Z THURSDAY THROUGH MONDAY/...
SHORT TERM...VFR CONDITIONS SHOULD DETERIORATE TO IFR AND LIFR
CONDITIONS TODAY AS SNOW SPREADS NORTHWARD. A PERIOD OF SLEET AND
FREEZING RAIN IS POSSIBLE ON THE COASTAL PLAIN THURSDAY NIGHT.
CONDITIONS IMPROVE FRIDAY.
LONG TERM...
MVFR AMD POSSIBLY IFR CONDS IN LIGHT SNOW SAT INTO SAT NIGHT. VFR
SUNDAY INTO MONDAY.
&&
.MARINE...
SHORT TERM...AS LOW PRESSURE MOVES THROUGH THE GULF OF MAINE
EXPECT WINDS TO REACH INTO THE GALE WARNING RANGE. THERE IS A LOW
POSSIBILITY OF STORM FORCE GUSTS OUTSIDE THE BAYS EARLY TONIGHT.
LONG TERM...
SCA CONDS PSBL LATE SAT THRU SUN AND AGAIN MON NIGHT AND TUE.
&&
.GYX WATCHES/WARNINGS/ADVISORIES...
ME...WINTER STORM WARNING UNTIL 9 AM EST FRIDAY FOR MEZ018-019-023-
024.
WINTER STORM WARNING UNTIL NOON EST FRIDAY FOR MEZ007>009-
012>014-020>022-025>028.
NH...WINTER STORM WARNING UNTIL 9 AM EST FRIDAY FOR NHZ003>010-013-
014.
WINTER STORM WARNING UNTIL NOON EST FRIDAY FOR NHZ001-002.
MARINE...GALE WARNING FROM 1 PM THIS AFTERNOON TO 11 AM EST FRIDAY FOR
ANZ150>154.
&&
$$
SCHWIBS
AREA FORECAST DISCUSSION
NWS GRAY ME
715 AM EST THU FEB 13 2014
.SYNOPSIS...
LOW PRESSURE WILL TRACK UP THE EAST COAST AND TOWARD CAPE COD
TODAY. SNOW WILL SPREAD NORTHWARD IN ADVANCE OF THE LOW. SNOW
WILL MIX WITH OR CHANGE TO SLEET AND FREEZING RAIN...ESPECIALLY
OVER COASTAL AND EASTERN AREAS OVERNIGHT TONIGHT BEFORE CHANGING
BACK TO SNOW AGAIN FRIDAY MORNING. THE STORM SYSTEM MOVES THROUGH
THE MARITIMES FRIDAY NIGHT. A SECOND LOW PRESSURE SYSTEM MOVES
BY...TRACKING FURTHER OUT TO SEA...ON SATURDAY. THIS SECOND LOW
THEN INTENSIFIES AS IT MOVES INTO THE MARITIMES SATURDAY NIGHT
DRAWING MORE COLD AIR INTO NEW ENGLAND ON GUSTY NORTHWEST WINDS.
HIGH PRESSURE BUILDS IN SUNDAY AND SUNDAY NIGHT BEFORE MOVING
OFFSHORE MONDAY. ANOTHER LOW PRESSURE SYSTEM MOVES IN FOR MONDAY
AND TUESDAY...PERHAPS BRINGING MIXED PRECIPITATION TO THE REGION.
&&
.NEAR TERM /THROUGH TONIGHT/...
UPDATE...
HAVE UPDATED GRIDS BASED ON CURRENT CONDTIONS. SNOW IS ROCKETING
QUICKLY UP THE COASTLINE AND SHOULD HAVE OVERSPREAD COASTAL YORK
COUNTY BY 8 AM AND IN THE PORTLAND AREA BY 9 AM WHICH IS IN LINE
WITH THE NEW HRRR RUN. HAVE ADJUSTED THE 6 HOUR SNOW GRID HIGHER FOR
SOUTHERN NH AND PORTIONS OF FAR SOUTHWEST MAINE ENDING AT 1
PM...AND THIS MAY NEED TO BE NUDGED UPWARDS FURTHER.
OTHERWISE...COLD AIR REMAINS INTACT THIS MORNING ACROSS THE
FORECAST AREA. A COASTAL FRONT SHOULD BE FORMING
SHORTLY...BRINGING LIGHT SNOWFALL TO THE ENTIRE COASTLINE BY MID MORNING.
PREV DISC...
SNOW CONTINUES TO SPREAD INTO SOUTHERN NEW ENGLAND EARLY THIS
MORNING. THIS PRECIPITATION SHIELD WILL RUN INTO A WALL OF VERY
COLD AND DRY AIR THIS MORNING AS IT ATTEMPT TO ENTER NORTHERN NEW
ENGLAND. NEVERTHELESS...WARM AIR ADVECTION PATTERN AND DEEP
MOISTURE SUPPLY FROM THE GULF OF MEXICO AND THE ATLANTIC WILL
ALLOW FOR THE PRECIPITATION TO QUICKLY OVERCOME THIS DRY COLUMN.
SNOW WILL SPREAD NORTH AND EAST THIS MORNING INTO OUR REGION WHERE
WINTER STORM WARNINGS BEGIN AT 7 AM. THE NAM...AS ALWAYS IS
GANGBUSTERS WITH QPF WHICH APPEARS TO BE OVERDONE (ALTHOUGH THE 4
KM NAM IS VERY IMPRESSIVE THIS MORNING). HOWEVER...THE GFS IS MUCH
DRIER. PREFER THE EURO WHICH IS A GOOD BLEND OF THESE SOLUTIONS.
THIS MODEL SOLUTION BRINGS 5 TO 8 INCHES OF SNOW TODAY AND INTO
THIS EVENING OVER FAR SOUTHERN AREAS. THIS IS IMPORTANT...AS WARM
AIR WILL ENTER THIS REGION DUE TO A DRYSLOT ROTATING IN OVER THE
MID LAYERS OF THE ATMOSPHERE. THIS WILL ALLOW WARM AIR TO ENTER
THE REGION ALOFT...BRINGING SLEET AND FREEZING RAIN TO SOUTHERN
AREAS...AND EFFECTIVELY SHUTTING DOWN THE ACCUMULATING SNOW FOR
MUCH OF THE NIGHT. AT THE SURFACE...TEMPERATURES WILL REMAIN COLD
WITH A NORTH WIND. HAVE THEREFORE REMOVED THE MENTION OF RAIN
ALONG THE COAST AS...AFTER OUR COLD...RADITIONAL COOLING NIGHT
LAST NIGHT...ALL AREAS ARE RUNNING LOWER TEMPERATURES THAN MOS
SOLUTIONS AT THIS TIME. PLENTY OF DRY AIR AT THE ONSET OF THE
PRECIPITATION WILL ALLOW FOR EVAPORATIONAL COOLING IN THE COLUMN
AS WELL.
FOR REASONS MENTIONED ABOVE...OUR WARM AIR ADVECTION "THUMP" WILL
ALLOW FOR SNOWFALL TOTALS TO JUST REACH INTO THE WARNING CRITERIA
OVER ROCKINGHAM COUNTY AS WELL...THEREFORE THIS COUNTY HAS BEEN
ADDED TO THE WARNINGS.
&&
.SHORT TERM /FRIDAY THROUGH FRIDAY NIGHT/...
972 MB LOW REACHES POINTS JUST EAST OF PORTLAND BY LATE TONIGHT
AND FRIDAY MORNING. THE MOUNTAINS WILL STILL BE HAVING
ACCUMULATING SNOW AT THAT TIME...WHILE WRAP AROUND PRECIPITATION
ATTEMPTS TO REENTER SOUTHERN AREAS. CLIMATOLOGY WOULD SUGGEST
THESE WRAP AROUND BANDS WILL CROSS CENTRAL AREAS...BUT ALSO HAVE A
DIFFICULT TIME REACHING THE COAST.
MOST AREAS WILL MAX OUT IN THE 8 TO 12 INCH RANGE FOR SNOWFALL
WITH THIS LATEST STORM. HOWEVER...THERE WILL BE LOCALLY HIGHER
AMOUNTS IN ANY BANDED PRECIPITATION AND ALSO OVER THE NE FACING
HIGH TERRAIN. LESS SNOW WILL ACCUMULATE NEAR THE COAST.
AROUND A THIRD OF AN INCH OF ICE MAY NOW OCCUR ALONG THE
COAST...WHICH COULD LEAD TO ISOLATED POWER OUTAGES.
&&
.LONG TERM /SATURDAY THROUGH WEDNESDAY/...
A WEAK RIDGE OF HIGH PRES MOVES OVER THE REGION FRI NIGHT BUT
QUICKLY GIVES WAY TO AN UPSTREAM TROF THAT WILL BE DIGGING INTO
NEW ENGLAND SATURDAY BRINGING SOME LIGHT SNOW ACROSS THE AREA. THIS
UPPER TROF DEVELOPS A STRONG SFC LOW WELL SOUTHEAST OF CAPE COD,
BUT EXACT PLACEMENT OF THE DVLPG SFC LOW FOR LATE SAT AND INTO
SAT EVNG BY THE MODELS WILL NEED TO BE WATCHED. LATEST EURO
SUGGESTS IT WILL BE A CLOSE CALL WHILE OTHER MODELS ARE FURTHER
EAST. BY LATE SAT NIGHT AND SUN THE TROF EXITS WELL TO THE EAST
AND CLEARING AND COLDER TEMPS RETURN. A LARGE RIDGE OF HIGH PRES
MOVES OVER NEW ENGLAND MONDAY BRINGING WITH IT A NICE DAY. THE NEXT
TROF APPROACHES ON TUES WITH AN ASSOC SFC LO THAT WILL PROBABLY
TRACK ALONG THE ST LAWRENCE VLY BY WITH BRING SOME LGT SNOW ACROSS
THE REGION. MIDWEEK HIGH PRES RETURNS WITH A WARMER SWLY FLOW TO
DVLP LATE IN THE WEEK.
&&
.AVIATION /12Z THURSDAY THROUGH MONDAY/...
SHORT TERM...VFR CONDITIONS SHOULD DETERIORATE TO IFR AND LIFR
CONDITIONS TODAY AS SNOW SPREADS NORTHWARD. A PERIOD OF SLEET AND
FREEZING RAIN IS POSSIBLE ON THE COASTAL PLAIN THURSDAY NIGHT.
CONDITIONS IMPROVE FRIDAY.
LONG TERM...
MVFR AMD POSSIBLY IFR CONDS IN LIGHT SNOW SAT INTO SAT NIGHT. VFR
SUNDAY INTO MONDAY.
&&
.MARINE...
SHORT TERM...AS LOW PRESSURE MOVES THROUGH THE GULF OF MAINE
EXPECT WINDS TO REACH INTO THE GALE WARNING RANGE. THERE IS A LOW
POSSIBILITY OF STORM FORCE GUSTS.
LONG TERM...
SCA CONDS PSBL LATE SAT THRU SUN AND AGAIN MON NIGHT AND TUE.
&&
.GYX WATCHES/WARNINGS/ADVISORIES...
ME...WINTER STORM WARNING UNTIL 9 AM EST FRIDAY FOR MEZ018-019-023-
024.
WINTER STORM WARNING FROM NOON TODAY TO NOON EST FRIDAY FOR
MEZ007>009-012>014-020>022-025>028.
NH...WINTER STORM WARNING UNTIL 9 AM EST FRIDAY FOR NHZ003>010-013-
014.
WINTER STORM WARNING FROM NOON TODAY TO NOON EST FRIDAY FOR
NHZ001-002.
MARINE...GALE WARNING FROM 1 PM THIS AFTERNOON TO 11 AM EST FRIDAY FOR
ANZ150>154.
&&
$$
JC
AREA FORECAST DISCUSSION
NWS BALTIMORE MD/WASHINGTON DC
1044 AM EST THU FEB 13 2014
.SYNOPSIS...
LOW PRESSURE OFF THE SOUTHEAST COAST WILL WILL INTENSIFY THROUGH
TONIGHT AS IT TRACKS UP THE MID-ATLANTIC COAST. HIGH PRESSURE WILL
BRIEFLY RETURN FRIDAY...BEFORE A COLD FRONT PASSES THROUGH FRIDAY
NIGHT. HIGH PRESSURE WILL BUILD OVERHEAD SATURDAY FOLLOWED BY
ANOTHER LOW PRESSURE TROUGH MOVING THROUGH SATURDAY NIGHT INTO
SUNDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
THE SFC LOW HAS INTENSIFIED OFF THE NORFOLK COAST THIS MORNING. AN
UPPER LEVEL LOW OVER THE GULF STATES WILL BEGIN TO PIVOT TO THE
NORTH TODAY APPROACHING THE MID ATLANITC.
HEAVY SNOW HAS OCCURRED ACROSS THE REGION IN THE PAST 12 HOURS AS
THE SFC LOW APPROACHED THE MID ATLANTIC. WARM AIR WRAPPED AROUND THE
LOW AND CHANGED THE SNOW IN SOUTH-CENTRAL MD AND DC TO A SLEET RAIN
MIX. FURTHER WEST SNOW...SLEET AND FZRA HAS BEEN REPORTED TO THE
EASTERN EDGE OF THE BAND ACROSS LOUDOUN/FREDERICK MD/CARROLL. THIS
CHANGE HAS BEEN APPARENT ON THE CC PRODUCT OF DUAL POL. LIGHT
PRECIP WILL LEAD TO ONLY A GLAZE TO A TENTH INCH OF ICE
ACCUM. MOST OF THE STRONG LIFT AND MID LEVEL CONVERGENCE HAS MOVED
NORTH OF THE MASON DIXON LINE WITH THE EXCEPTION OF THE AREA THAT
IS CO LOCATED WITH THE BAND OF HEAVY SNOW. REPORTS UP TO 20 INCHES
HAVE BEEN REPORTED UNDER THIS BAND. THE TRACK OF THE LOW WILL
CONTINUE TO MOVE NORTHWARD THIS MORNING AND THE BAND LOCATED EAST
OF THE BLUE RIDGE WILL EVENTUALLY BREAK DOWN AND MOVE NORTHWARD
AS THE DRY SLOT MOVES INTO THE ENTIRE REGION. THIS WILL GIVE A
SHORT BREAK OF SNOW...SLEET AND RAIN BEFORE THE NEXT ROUND OF SNOW IS
UPON US LATER TODAY.
THE UPPER LOW THAT WILL PIVOT NORTHWARD AND MOVE ACROSS THE MID
ATLANTIC WILL BRING ANOTHER ROUND OF SNOW TO THE AREA. NAM AND GFS
ARE BOTH SHOWING MID LEVEL CONVERGENCE MOVING ACROSS THE REGION FROM
WEST TO EAST. HEAVY SNOW ACROSS NW MD...WEST VIRGINIA AND ACROSS
THE CAROLINAS IS GOING TO MOVE TOWARDS THE MID ATLANTIC THIS
AFTERNOON AND EVENING. WRAP AROUND MOISTURE FROM THE SFC LOW AND
STRONG LIFT AND DYNAMICS FROM THE UPPER LOW WILL LEAD TO
ADDITIONAL ACCUMULATIONS. HRRR AND WRF ALSO SHOW THIS ACTIVITY
CROSSING THE AREA. THERE ARE SOME DIFFERENCES IN THE AMOUNT OF
MOISTURE EXPECTED BUT AN ADDITIONAL 2-4 INCHES WILL BE POSSIBLE
FOR THE MID ATLANTIC. MOST WINTER WEATHER WARNINGS WILL CONTINUE
TO COVER THE SECOND ROUND OF SNOW THAT IS EXPECTED THROUGH
TONIGHT. AS PRECIP ENDS ACROSS THE I-95 CORRIDOR AROUND DC THE
WINTER WEATHER WARNING WILL DROP THIS AFTERNOON. A WINTER WEATHER
ADVISORY HAS ALREADY DROPPED IN FAR SOUTHERN MARYLAND. A DIFFERENT
WINTER WEATHER ADVISORY IS IN EFFECT LATE THIS AFTERNOON THROUGH
TONIGHT FOR I-95 AND EAST.
&&
.SHORT TERM /FRIDAY THROUGH SATURDAY NIGHT/...
THE LAST WAVES OF PRECIP ASSOCIATED W/ THE PARENT UPPER LOW LATE
THU WILL BE OUT OF THE AREA AND WELL OFF TO THE NE BY SUNRISE FRI.
WITH TEMPS ONLY DROPPING INTO THE L20 FOR OVERNIGHT LOWS...IT WILL
BE A GOOD START TO A RELATIVELY WARMER DAY ON FRI. SKIES WILL
LARGELY CLEAR OUT DURING THE MRNG HRS...W/ A BREEZY SFC WIND
ESPECIALLY ALONG THE HIGHER TERRAIN. THE STEADY SWLY FLOW WILL BE
A RELATIVELY WARMER WIND AND HELP TEMPS SLIDE UP INTO THE M-U30S
DURING THE AFTN HRS - AIDING IN MELTING OF SNOWFALL FROM THE
CURRENT EVENT.
CONDITIONS WILL CHANGE RAPIDLY HOWEVER...AS A WEAK SHORTWAVE
QUICKLY SLIDES IN FROM THE UPPER MIDWEST - GATHERS UP SOME
MOISTURE AND PASSES OVER THE AREA LATE FRI NIGHT INTO EARLY SAT.
GOOD CONSENSUS ON THIS FEATURE...SPREADING LIGHT QPF AMOUNTS
ACROSS THE AREA OVERNIGHT BEFORE PUSHING OFF THE COAST BY DAWN
SAT. MODEL TEMP PROFILES SUGGEST A BRIEF RAIN/SNOW MIX AT ONSET
BUT ALL-SNOW POSSIBLE HEADING INTO THE EARLY MRNG HRS.
AFTER THIS LATEST UPPER LEVEL FEATURE MOVES AWAY FROM THE
AREA...BRISK NW WINDS WILL BE LEFT IN ITS WAKE DESPITE CLEARING
SKIES. TEMPS WILL AGAIN ONLY APPROACH THE FREEZING MARK BOTH SAT
AND SUN...THOUGH CHANGES ARE ON THE WAY.
&&
.LONG TERM /SUNDAY THROUGH WEDNESDAY/...
THE RECENT ACTIVE PATTERN TAKE START TO QUIET DOWN A BIT HEADING
INTO EARLY NEXT WEEK...THOUGH A COUPLE OF SYSTEMS OF NOTE POSSIBLE
EVEN AS WE LOOK TO A BRIEF WARM-UP. AFTER THE FRI NIGHT/SAT
THROUGH PASSAGE...A MUCH WEAKER AND DRIER UPPER WAVE WILL SWING
THRU ON SUNDAY. THIS FEATURE WILL MERELY SWING ANOTHER BRIEF BATCH
OF UPSLOPE SNOWS TO THE MTNS...MOSTLY CLOUDY SKIES FOR THE REST OF
THE AREA AND JUST REINFORCES COLDER AIR - PREVENTING US FROM
CRACKING THE FREEZING MARK FOR ANOTHER DAY.
A BRIEF REPRIEVE ON MONDAY W/ HIGHS PULLING BACK UP INTO THE
U30S/L40S BEFORE YET ANOTHER LOW PRESSURE SYSTEM SLIDES ACROSS THE
REGION AFTER A QUICK SPIN-UP JUST TO OUR WEST. THE EURO AND GFS
ARE ACTUALLY IN DECENT AGREEMENT THIS FAR OUT...SHOWING THE PARENT
LOW PASSING BY TO OUR NORTH - DRAGGING THE COLD FRONTAL REGION
ACROSS OUR AREA. THIS TYPE OF PASSAGE WOULD ENSURE MORE OF A
WARMER REGIME THAN THE FRI NIGHT STORM SYSTEM. THEREFORE...WHAT
LITTLE QPF MAKES IT E OF THE MTNS WILL BE EITHER ALL RAIN OR A
RAIN/SNOW MIX ACROSS A BULK OF THE CWA. THE ATYPICAL EFFECT AFTER
THE SYSTEM`S PASSAGE WILL BE A WARM-UP HEADING INTO THE DAYTIME
HRS ON TUE - POST COLD FRONT. HIGHS ON TUE COULD NEAR THE 50 DEG
MARK...WHICH IS NEAR-AVG FOR THIS TIME OF YEAR AND THE WARMEST
TEMPS SINCE THE START OF THE MONTH.
THE MIDDLE OF NEXT WEEK MAY BE EVEN WARMER AS A LARGE BERMUDA HIGH
SETS UP OFF THE ATLC COAST WHILE A STORM SYSTEM GEARS-UP OVER THE
GREAT PLAINS.
&&
.AVIATION /16Z THURSDAY THROUGH MONDAY/...
IFR CONDITIONS WILL CONTINUE TODAY AS A SFC LOW APPROACHES THE MID
ATLANTIC. SNOW WILL END AT MRB IN THE NEXT FEW HOURS BEFORE
ANOTHER ROUND BEGINS THIS AFTERNOON. -SNPLRA WILL OCCUR AT IAD-
CHO-DCA-MTN-BWI THROUGH THIS AFTERNOON. ANOTHER ROUND OF SNOW IS
EXPECTED TO CROSS THE REGION LATE THIS AFTERNOON AND TONIGHT
REDUCING VSBYS AND CEILINGS. LIFR CONDITIONS ARE EXPECTED DURING
THIS TIME. NORTHERLY THIS MORNING WILL SHIFT TO THE NORTHWEST
TONIGHT WITH GUSTS AROUND 25 TO 30 KNOTS.
SKIES CLEAR OUT ON FRI BEHIND THE STORM SYSTEM...W/ LIGHT SW WINDS
BUT STRONGER LOW LEVEL WINDS IN ITS WAKE. A FAST-MOVING SHORTWAVE
WILL LIKELY SPREAD SOME MORE LIGHT PRECIP - MAINLY SNOW ON FRI
NIGHT INTO EARLY SAT BUT WINDS WILL PICK UP AFTER ITS EXIT OFF THE
COAST FOR THE DAYTIME HRS SAT. BRISK 20-30KT WINDS WILL SPREAD
ACROSS THE REGION UNTIL LATE EVE...THEN DROP INTO THRU MUCH OF
NEXT WEEK. ANOTHER WEAK LOW PRESSURE SYSTEM`S PASSAGE ON TUE THEN
A BRIEF PERIOD OF HIGH PRESSURE FOR THE MIDDLE OF NEXT WEEK.
&&
.MARINE...
COASTAL LOW PRESSURE WILL INTENSIFY AS IT MOVES UP THE MID-ATLANTIC
COAST TODAY AND TONIGHT. GUSTY NORTHEAST WINDS THIS MORNING WILL
SHIFT TO THE NORTH THIS AFTERNOON AND THEN TOWARD THE NORTHWEST
TONIGHT. A GALE WARNING IS IN EFFECT THROUGH TONIGHT FOR THE
MARYLAND CHESAPEAKE BAY FROM SANDY POINT TO SMITH POINT AND FOR THE
LOWER TIDAL POTOMAC RIVER FROM COBB ISLAND TO SMITH POINT. A SMALL
CRAFT ADVISORY IS IN EFFECT FOR THE REST OF THE WATERS DURING THIS
TIME.
WELL AFTER THE EXIT OF THE CURRENT POTENT STORM SYSTEM...SCA CRIT
GUSTS WILL BE POSSIBLE WELL INTO FRI. THE NEXT SEVERAL DAYS THEN
WILL BE AN EVERY-OTHER-DAY PASSAGE OF A LOW PRESSURE SYSTEM. THE
STRONGEST OF THESE WILL BE AN UPPER WAVE FRI NIGHT INTO EARLY
SAT...USHERING IN ANOTHER ROUND OF SOLID SCA GUSTS FOR MUCH OF
SATURDAY BEHIND THE SYSTEM. WINDS WILL THEN DROP OFF FOR MUCH OF
NEXT WEEK OUTSIDE OF A BRIEF INCR ON TUE AS AN LOW PRESSURE SYSTEM
QUICKLY SLIDES ACROSS THE REGION.
&&
.TIDES/COASTAL FLOODING...
A NORTH-NORTHEAST FLOW WILL CAUSE ELEVATED WATER LEVELS TODAY AS A
COASTAL LOW PASSES BY TO THE EAST. AT THIS TIME...IT APPEARS THAT
LEVELS WILL BE JUST UNDER MINOR TIDAL THRESHOLDS BUT WILL NEED TO BE
WATCHED AS THE GRADIENT INTENSIFIES TONIGHT IN STEP WITH DEEPENING
LOW PRESSURE.
&&
.LWX WATCHES/WARNINGS/ADVISORIES...
DC...WINTER WEATHER ADVISORY FROM 5 PM THIS AFTERNOON TO 1 AM EST
FRIDAY FOR DCZ001.
WINTER STORM WARNING UNTIL 3 PM EST THIS AFTERNOON FOR DCZ001.
MD...WINTER STORM WARNING UNTIL 9 PM EST THIS EVENING FOR MDZ501-
502.
WINTER WEATHER ADVISORY FROM 5 PM THIS AFTERNOON TO 1 AM EST
FRIDAY FOR MDZ013-014-016>018.
WINTER STORM WARNING UNTIL 3 PM EST THIS AFTERNOON FOR MDZ013-
014-016.
WINTER STORM WARNING UNTIL 5 AM EST FRIDAY FOR MDZ003>007-
009>011.
VA...WINTER STORM WARNING UNTIL 9 PM EST THIS EVENING FOR
VAZ025>027-029-036>040-050-051-056-503-504.
WINTER WEATHER ADVISORY FROM 5 PM THIS AFTERNOON TO 1 AM EST
FRIDAY FOR VAZ054-057.
WINTER STORM WARNING UNTIL 3 PM EST THIS AFTERNOON FOR VAZ054-
057.
WINTER STORM WARNING UNTIL 5 AM EST FRIDAY FOR VAZ028-030-031-
042-052-053-055-501-502.
WV...WINTER STORM WARNING UNTIL 9 PM EST THIS EVENING FOR WVZ050-
055-501>506.
WINTER STORM WARNING UNTIL 5 AM EST FRIDAY FOR WVZ051>053.
MARINE...GALE WARNING UNTIL 6 AM EST FRIDAY FOR ANZ532>534-537-540>543.
SMALL CRAFT ADVISORY UNTIL 6 AM EST FRIDAY FOR ANZ530-531-535-
536-538-539.
&&
$$
SYNOPSIS...
NEAR TERM...BJL/HAS
SHORT TERM...GMS
LONG TERM...GMS
AVIATION...BJL/GMS
MARINE...BJL/GMS
TIDES/COASTAL FLOODING...
AREA FORECAST DISCUSSION
NWS PITTSBURGH PA
1005 AM EST THU FEB 13 2014
.SYNOPSIS...
EAST COAST LOW PRESSURE WILL SPREAD SNOW TO AREAS EAST OF
INTERSTATE 79 TODAY BEFORE MOVING OFF TOWARDS NEW ENGLAND. A
SHORTWAVE WILL BRING THE CHANCE FOR ADDITIONAL SNOW FRIDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
WITH 10AM UPDATE...CONTINUE TO BUMP UP SNOW AMOUNTS IN THE HIGHER
ELEVATIONS OF WV/MD. CONTINUE TO REACH SNOW RATES OF AN INCH AN
HOUR IN SOME LOCATIONS. HIGHEST ELEVATIONS COULD RECEIVE AN
ADDITIONAL 6 INCHES OF SNOW THROUGH THE REST OF THE DAY. HAVE LEFT
SNOW FORECASTS UNTOUCHED OUTSIDE THE WARNING AREA AND THE
FAYETTE/WESTMORELAND RIDGES. WESTERN EDGE OF SNOW HAVE PIVOTED
SLIGHTLY FARTHER NORTH OVER PENNSYLVANIA COUNTIES OVER THE LAST
THREE HOURS AS EXPECTED.
POST DAWN UPDATE WAS ISSUED TO ADD A TIER OF COUNTIES TO THE WRN
FLANK OF THE WINTER WEATHER ADVISORY AFTER PRE DAWN REPORTS OF 1
TO 2 INCHES ALREADY IN THOSE AREAS. THOUGH MID/UPR DRY SLOT IS
ENCROACHING AND PRIMARY FRONTOGENETICAL FORCING ZONE HAS SHIFTED
EWD ALREADY...SNOW IS EXPECTED TO CONTINUE FOR MUCH OF THE DAY AS
WELL DEFINED DEFORMATION ZONE WRAPS OVER THE REGION.
PREVIOUS...
DEFORMATION BAND OF HEAVY SNOW HAS MADE IT INTO
PRESTON...TUCKER...AND GARRETT COUNTIES THIS MORNING. EXPECT
SNOWFALL RATES EXCEEDING AN INCH AN HOUR AS THIS BAND MOVES
NORTHWARD. WITH SNOWFALL REPORTS ALREADY IN THE 3-4 INCH RANGE
OVER TUCKER AND GARRETT COUNTIES...HAVE SLIGHTLY BUMPED UP
SNOWFALL AMOUNTS. THE DRY SLOT SHOULD STILL DECREASE RATES BRIEFLY
THIS MORNING...AS IS ALREADY BEING SEEN ON THE NORTHERN FRINGE OF
THE PRECIP ON RADAR OVER OUR CWA. SNOW HAS STRUGGLED TO GO MUCH
FARTHER NORTH THAN THE VERY TIP OF ALLEGHENY COUNTY YET THIS
MORNING ALTHOUGH THE DETERMINISTIC MODEL AND THE HRRR CONTINUE TO
SUGGEST SOME LIGHT SNOW SHOULD MAKE IT TO PITTSBURGH.
AS THE NEGATIVELY TILTED TROUGH STRENGTHS THE COASTAL LOW...THE
TROWAL AND ENHANCED SNOWFALL SHOULD MOVE NORTH AND PIVOT ACROSS
THE COUNTIES EAST OF I79 THROUGH THE AFTERNOON. THE LOW WILL MOVE
TOWARD THE DELMARVA AND REACH LONG ISLAND BY THIS TONIGHT...TAKING
THE BULK OF THE MOISTURE WITH IT. SNOW SHOULD BEGIN TO TAPER OFF
BY THIS EVENING FROM WEST TO EAST. A BRIEF PERIOD OF FREEZING
DRIZZLE COULD BE POSSIBLE OVER THE RIDGES BEFORE A WEAK FRONT
ASSOCIATED WITH A SHORTWAVE CROSSING THE GREAT LAKES CROSSES THE
REGION OVERNIGHT.
DESPITE THE EASTERLY WINDS...TEMPERATURES SHOULD REACH CLOSE TO
FREEZING ACROSS MUCH OF THE REGION TODAY AND SHOULD NOT FALL TOO
MUCH UNTIL THE FRONTAL PASSAGE LATE TONIGHT.
&&
.SHORT TERM /FRIDAY THROUGH SATURDAY NIGHT/...
COLD ADVECTION MAY BRING THE CHANCE FOR SOME SNOW SHOWERS EARLY
FRIDAY BEFORE THE NEXT SHORTWAVE DIVES SOUTH TOWARD WEST VIRGINIA.
THE MODELS ARE HANDLING THIS SECOND SHORTWAVE BETTER THAN THE LAST
COUPLE OF NIGHTS...SUGGESTING THAT THE BULK OF THE MOISTURE WILL
STAY SOUTH OF I-70. FOR NOW...CARRIED THE HIGHEST POPS TO THE
SOUTH BUT MAINTAINED CHANCE FURTHER NORTH SINCE THE MODELS ARE
STILL TRYING TO SQUEEZE OUT SOME PRECIPITATION IN THE COLD
ADVECTION EARLY FRIDAY.
NORTHWEST FLOW MAY CONTINUE THE CHANCE FOR SOME SCATTERED SNOW
SHOWERS UP NORTH AND IN THE RIDGES ON SATURDAY BUT WITH A LACK OF
MOISTURE AND THE FROZEN LAKE ERIE...VERY LITTLE ACCUMULATION IS
EXPECTED.
YET ANOTHER SHORTWAVE WILL DIVE TOWARD THE REGION LATE SATURDAY
NIGHT AND SUNDAY. THIS SYSTEM LOOKS TO BE RELATIVELY MOISTURE
STARVED SO VERY LIGHT ACCUMULATIONS WERE KEPT IN THE FORECAST.
TEMPERATURES CONTINUE TO TREND BELOW SEASONAL AVERAGES DUE TO THE
SERIES OF WAVES AND COLD ADVECTION.
&&
.LONG TERM /SUNDAY THROUGH WEDNESDAY/...
LONG RANGE MODELS ARE HAVING A DIFFICULT TIME HANDLING A COUPLE OF
QUICK MOVING SHORT WAVES IN THE SHORT TERM...WHICH TRANSLATES TO
GREATER DIFFERENCES IN THE EXTENDED PERIOD. ONE THING THAT IS
GENERALLY AGREED UPON IS A WARMUP TO AT LEAST NORMAL TEMPERATURES
NEXT WEEK. SOUTHWEST FLOW BETWEEN AN EXITING WEAK LOW SUN AND A
QUICK MOVING FRONT MON NIGHT WILL RESULT IN STRONG WAA WHICH
SHOULD LEAD TO RAIN BEING THE PRIMARY PRECIPITATION TYPE ALONG THE
FRONT. ELECTING TO KEEP POPS IN THE CHC RANGE FOR NOW AS
CONSIDERABLE TIMING DIFFERENCES BETWEEN THE EC/GFS EXIST.
HIGH PRESSURE BUILDS IN MID-WEEK WITH A RETURN TO SOUTHWEST FLOW
ALOFT...ULTIMATELY REINFORCING THE WARMING TREND.
&&
.AVIATION /15Z THURSDAY THROUGH MONDAY/...
DEGRADED CONDITIONS...INCLUDING IFR...WL MAINTAINED FOR ALL PORTS
EAST OF A FKL TO ZZV LINE TDA AS SNOW WRAPS OVR THE REGION IN
ASSOCIATION WITH CROSSING MID LVL LOW PRES. NELY SFC WIND WL
FURTHER BACK TO THE NORTH AND SHOULD INCRS TO NR 10 KTS AS SFC LOW
MOVS UP THE EAST COAST.
IMPROVEMENT CAN BE EXPECTED TNGT WITH EWD PROGRESS OF THAT
SYSTEM...THOUGH MVFR STRATOCU MAY LINGER INTO THE NGT.
.OUTLOOK..../FRIDAY THROUGH MONDAY/...
SEVERAL FAST MOVING DISTURBANCES SHOULD RESULT IN PERIODIC RESTRICTIONS
THROUGH THE WEEKEND.
&&
.PBZ WATCHES/WARNINGS/ADVISORIES...
MD...WINTER STORM WARNING UNTIL 7 PM EST THIS EVENING FOR MDZ001.
OH...NONE.
PA...WINTER WEATHER ADVISORY UNTIL 7 PM EST THIS EVENING FOR PAZ023-
031-073>076.
WV...WINTER WEATHER ADVISORY UNTIL 7 PM EST THIS EVENING FOR WVZ021-
022.
WINTER STORM WARNING UNTIL 7 PM EST THIS EVENING FOR WVZ023-
041.
&&
$$
AREA FORECAST DISCUSSION
NWS PITTSBURGH PA
740 AM EST THU FEB 13 2014
.SYNOPSIS...
EAST COAST LOW PRESSURE WILL SPREAD SNOW TO AREAS EAST OF
INTERSTATE 79 TODAY BEFORE MOVING OFF TOWARDS NEW ENGLAND. A
SHORTWAVE WILL BRING THE CHANCE FOR ADDITIONAL SNOW FRIDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
POST DAWN UPDATE WAS ISSUED TO ADD A TIER OF COUNTIES TO THE WRN
FLANK OF THE WINTER WEATHER ADVISORY AFTER PRE DAWN REPORTS OF 1
TO 2 INCHES ALREADY IN THOSE AREAS. THOUGH MID/UPR DRY SLOT IS
ENCROACHING AND PRIMARY FRONTOGENETICAL FORCING ZONE HAS SHIFTED
EWD ALREADY...SNOW IS EXPECTED TO CONTINUE FOR MUCH OF THE DAY AS
WELL DEFINED DEFORMATION ZONE WRAPS OVER THE REGION.
PREVIOUS...
DEFORMATION BAND OF HEAVY SNOW HAS MADE IT INTO
PRESTON...TUCKER...AND GARRETT COUNTIES THIS MORNING. EXPECT
SNOWFALL RATES EXCEEDING AN INCH AN HOUR AS THIS BAND MOVES
NORTHWARD. WITH SNOWFALL REPORTS ALREADY IN THE 3-4 INCH RANGE
OVER TUCKER AND GARRETT COUNTIES...HAVE SLIGHTLY BUMPED UP
SNOWFALL AMOUNTS. THE DRY SLOT SHOULD STILL DECREASE RATES BRIEFLY
THIS MORNING...AS IS ALREADY BEING SEEN ON THE NORTHERN FRINGE OF
THE PRECIP ON RADAR OVER OUR CWA. SNOW HAS STRUGGLED TO GO MUCH
FARTHER NORTH THAN THE VERY TIP OF ALLEGHENY COUNTY YET THIS
MORNING ALTHOUGH THE DETERMINISTIC MODEL AND THE HRRR CONTINUE TO
SUGGEST SOME LIGHT SNOW SHOULD MAKE IT TO PITTSBURGH.
AS THE NEGATIVELY TILTED TROUGH STRENGTHS THE COASTAL LOW...THE
TROWAL AND ENHANCED SNOWFALL SHOULD MOVE NORTH AND PIVOT ACROSS
THE COUNTIES EAST OF I79 THROUGH THE AFTERNOON. THE LOW WILL MOVE
TOWARD THE DELMARVA AND REACH LONG ISLAND BY THIS TONIGHT...TAKING
THE BULK OF THE MOISTURE WITH IT. SNOW SHOULD BEGIN TO TAPER OFF
BY THIS EVENING FROM WEST TO EAST. A BRIEF PERIOD OF FREEZING
DRIZZLE COULD BE POSSIBLE OVER THE RIDGES BEFORE A WEAK FRONT
ASSOCIATED WITH A SHORTWAVE CROSSING THE GREAT LAKES CROSSES THE
REGION OVERNIGHT.
DESPITE THE EASTERLY WINDS...TEMPERATURES SHOULD REACH CLOSE TO
FREEZING ACROSS MUCH OF THE REGION TODAY AND SHOULD NOT FALL TOO
MUCH UNTIL THE FRONTAL PASSAGE LATE TONIGHT.
&&
.SHORT TERM /FRIDAY THROUGH SATURDAY NIGHT/...
COLD ADVECTION MAY BRING THE CHANCE FOR SOME SNOW SHOWERS EARLY
FRIDAY BEFORE THE NEXT SHORTWAVE DIVES SOUTH TOWARD WEST VIRGINIA.
THE MODELS ARE HANDLING THIS SECOND SHORTWAVE BETTER THAN THE LAST
COUPLE OF NIGHTS...SUGGESTING THAT THE BULK OF THE MOISTURE WILL
STAY SOUTH OF I-70. FOR NOW...CARRIED THE HIGHEST POPS TO THE
SOUTH BUT MAINTAINED CHANCE FURTHER NORTH SINCE THE MODELS ARE
STILL TRYING TO SQUEEZE OUT SOME PRECIPITATION IN THE COLD
ADVECTION EARLY FRIDAY.
NORTHWEST FLOW MAY CONTINUE THE CHANCE FOR SOME SCATTERED SNOW
SHOWERS UP NORTH AND IN THE RIDGES ON SATURDAY BUT WITH A LACK OF
MOISTURE AND THE FROZEN LAKE ERIE...VERY LITTLE ACCUMULATION IS
EXPECTED.
YET ANOTHER SHORTWAVE WILL DIVE TOWARD THE REGION LATE SATURDAY
NIGHT AND SUNDAY. THIS SYSTEM LOOKS TO BE RELATIVELY MOISTURE
STARVED SO VERY LIGHT ACCUMULATIONS WERE KEPT IN THE FORECAST.
TEMPERATURES CONTINUE TO TREND BELOW SEASONAL AVERAGES DUE TO THE
SERIES OF WAVES AND COLD ADVECTION.
&&
.LONG TERM /SUNDAY THROUGH WEDNESDAY/...
LONG RANGE MODELS ARE HAVING A DIFFICULT TIME HANDLING A COUPLE OF
QUICK MOVING SHORT WAVES IN THE SHORT TERM...WHICH TRANSLATES TO
GREATER DIFFERENCES IN THE EXTENDED PERIOD. ONE THING THAT IS
GENERALLY AGREED UPON IS A WARMUP TO AT LEAST NORMAL TEMPERATURES
NEXT WEEK. SOUTHWEST FLOW BETWEEN AN EXITING WEAK LOW SUN AND A
QUICK MOVING FRONT MON NIGHT WILL RESULT IN STRONG WAA WHICH
SHOULD LEAD TO RAIN BEING THE PRIMARY PRECIPITATION TYPE ALONG THE
FRONT. ELECTING TO KEEP POPS IN THE CHC RANGE FOR NOW AS
CONSIDERABLE TIMING DIFFERENCES BETWEEN THE EC/GFS EXIST.
HIGH PRESSURE BUILDS IN MID-WEEK WITH A RETURN TO SOUTHWEST FLOW
ALOFT...ULTIMATELY REINFORCING THE WARMING TREND.
&&
.AVIATION /13Z THURSDAY THROUGH MONDAY/...
DEGRADED CONDITIONS...INCLUDING IFR...WL MAINTAINED FOR ALL PORTS
EAST OF A FKL TO ZZV LINE TDA AS SNOW WRAPS OVR THE REGION IN
ASSOCIATION WITH CROSSING MID LVL LOW PRES. NELY SFC WIND WL
FURTHER BACK TO THE NORTH AND SHOULD INCRS TO NR 10 KTS AS SFC LOW
MOVS UP THE EAST COAST.
IMPROVEMENT CAN BE EXPECTED TNGT WITH EWD PROGRESS OF THAT
SYSTEM...THOUGH MVFR STRATOCU MAY LINGER INTO THE NGT.
.OUTLOOK..../FRIDAY THROUGH MONDAY/...
SEVERAL FAST MOVING DISTURBANCES SHOULD RESULT IN PERIODIC RESTRICTIONS
THROUGH THE WEEKEND.
&&
.PBZ WATCHES/WARNINGS/ADVISORIES...
MD...WINTER STORM WARNING UNTIL 7 PM EST THIS EVENING FOR MDZ001.
OH...NONE.
PA...WINTER WEATHER ADVISORY UNTIL 7 PM EST THIS EVENING FOR PAZ023-
031-073>076.
WV...WINTER WEATHER ADVISORY UNTIL 7 PM EST THIS EVENING FOR WVZ021-
022.
WINTER STORM WARNING UNTIL 7 PM EST THIS EVENING FOR WVZ023-
041.
&&
$$
15
AREA FORECAST DISCUSSION
NWS PITTSBURGH PA
617 AM EST THU FEB 13 2014
.SYNOPSIS...
EAST COAST LOW PRESSURE WILL SPREAD SNOW TO AREAS EAST OF
INTERSTATE 79 TODAY BEFORE MOVING OFF TOWARDS NEW ENGLAND. A
SHORTWAVE WILL BRING THE CHANCE FOR ADDITIONAL SNOW FRIDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
DEFORMATION BAND OF HEAVY SNOW HAS MADE IT INTO
PRESTON...TUCKER...AND GARRETT COUNTIES THIS MORNING. EXPECT
SNOWFALL RATES EXCEEDING AN INCH AN HOUR AS THIS BAND MOVES
NORTHWARD. WITH SNOWFALL REPORTS ALREADY IN THE 3-4 INCH RANGE
OVER TUCKER AND GARRETT COUNTIES...HAVE SLIGHTLY BUMPED UP
SNOWFALL AMOUNTS. THE DRY SLOT SHOULD STILL DECREASE RATES BRIEFLY
THIS MORNING...AS IS ALREADY BEING SEEN ON THE NORTHERN FRINGE OF
THE PRECIP ON RADAR OVER OUR CWA. SNOW HAS STRUGGLED TO GO MUCH
FARTHER NORTH THAN THE VERY TIP OF ALLEGHENY COUNTY YET THIS
MORNING ALTHOUGH THE DETERMINISTIC MODEL AND THE HRRR CONTINUE TO
SUGGEST SOME LIGHT SNOW SHOULD MAKE IT TO PITTSBURGH.
AS THE NEGATIVELY TILTED TROUGH STRENGTHS THE COASTAL LOW...THE
TROWAL AND ENHANCED SNOWFALL SHOULD MOVE NORTH AND PIVOT ACROSS
THE COUNTIES EAST OF I79 THROUGH THE AFTERNOON. THE LOW WILL MOVE
TOWARD THE DELMARVA AND REACH LONG ISLAND BY THIS TONIGHT...TAKING
THE BULK OF THE MOISTURE WITH IT. SNOW SHOULD BEGIN TO TAPER OFF
BY THIS EVENING FROM WEST TO EAST. A BRIEF PERIOD OF FREEZING
DRIZZLE COULD BE POSSIBLE OVER THE RIDGES BEFORE A WEAK FRONT
ASSOCIATED WITH A SHORTWAVE CROSSING THE GREAT LAKES CROSSES THE
REGION OVERNIGHT.
DESPITE THE EASTERLY WINDS...TEMPERATURES SHOULD REACH CLOSE TO
FREEZING ACROSS MUCH OF THE REGION TODAY AND SHOULD NOT FALL TOO
MUCH UNTIL THE FRONTAL PASSAGE LATE TONIGHT.
&&
.SHORT TERM /FRIDAY THROUGH SATURDAY NIGHT/...
COLD ADVECTION MAY BRING THE CHANCE FOR SOME SNOW SHOWERS EARLY
FRIDAY BEFORE THE NEXT SHORTWAVE DIVES SOUTH TOWARD WEST VIRGINIA.
THE MODELS ARE HANDLING THIS SECOND SHORTWAVE BETTER THAN THE LAST
COUPLE OF NIGHTS...SUGGESTING THAT THE BULK OF THE MOISTURE WILL
STAY SOUTH OF I-70. FOR NOW...CARRIED THE HIGHEST POPS TO THE
SOUTH BUT MAINTAINED CHANCE FURTHER NORTH SINCE THE MODELS ARE
STILL TRYING TO SQUEEZE OUT SOME PRECIPITATION IN THE COLD
ADVECTION EARLY FRIDAY.
NORTHWEST FLOW MAY CONTINUE THE CHANCE FOR SOME SCATTERED SNOW
SHOWERS UP NORTH AND IN THE RIDGES ON SATURDAY BUT WITH A LACK OF
MOISTURE AND THE FROZEN LAKE ERIE...VERY LITTLE ACCUMULATION IS
EXPECTED.
YET ANOTHER SHORTWAVE WILL DIVE TOWARD THE REGION LATE SATURDAY
NIGHT AND SUNDAY. THIS SYSTEM LOOKS TO BE RELATIVELY MOISTURE
STARVED SO VERY LIGHT ACCUMULATIONS WERE KEPT IN THE FORECAST.
TEMPERATURES CONTINUE TO TREND BELOW SEASONAL AVERAGES DUE TO THE
SERIES OF WAVES AND COLD ADVECTION.
&&
.LONG TERM /SUNDAY THROUGH WEDNESDAY/...
LONG RANGE MODELS ARE HAVING A DIFFICULT TIME HANDLING A COUPLE OF
QUICK MOVING SHORT WAVES IN THE SHORT TERM...WHICH TRANSLATES TO
GREATER DIFFERENCES IN THE EXTENDED PERIOD. ONE THING THAT IS
GENERALLY AGREED UPON IS A WARMUP TO AT LEAST NORMAL TEMPERATURES
NEXT WEEK. SOUTHWEST FLOW BETWEEN AN EXITING WEAK LOW SUN AND A
QUICK MOVING FRONT MON NIGHT WILL RESULT IN STRONG WAA WHICH
SHOULD LEAD TO RAIN BEING THE PRIMARY PRECIPITATION TYPE ALONG THE
FRONT. ELECTING TO KEEP POPS IN THE CHC RANGE FOR NOW AS
CONSIDERABLE TIMING DIFFERENCES BETWEEN THE EC/GFS EXIST.
HIGH PRESSURE BUILDS IN MID-WEEK WITH A RETURN TO SOUTHWEST FLOW
ALOFT...ULTIMATELY REINFORCING THE WARMING TREND.
&&
.AVIATION /11Z THURSDAY THROUGH MONDAY/...
SNOW BANDS SETTING UP FROM MGW NORTH TO LBE AND IDI. SNOW BANDS
WILL STAY QUASI-STATIONARY THROUGH ABT 15Z AS THE MAIN LOW PUSHES UP
THE EAST COAST TODAY. IFR SNOW EXPECTED IN MGW AND LBE THROUGH AT
LEAST MIDDAY. SEVERAL OTHER SITES WILL DETERIORATE TO MVFR
CIGS...AS THE WESTERN EDGE OF SNOW BAND SLOWLY ENCROACHES E TO W
BEFORE RETREATING AGAIN BY AFTERNOON. FKL/ZZV WILL STAY VFR AS THE SYSTEM
HOLDS FAR ENOUGH TO THE EAST. WINDS WILL KEEP AN EASTERLY
COMPONENT THROUGH MID- MORNING BEFORE GRADUALLY BACKING TO
WESTERLY THURS NIGHT. WIND SPEED WILL GENERALLY REMAIN LESS THAN
10 KTS THROUGHOUT.
.OUTLOOK..../THURSDAY NIGHT THROUGH MONDAY/...
SEVERAL FAST MOVING DISTURBANCES SHOULD RESULT IN PERIODIC
RESTRICTIONS THROUGH THE WEEKEND.
&&
.PBZ WATCHES/WARNINGS/ADVISORIES...
MD...WINTER STORM WARNING UNTIL 7 PM EST THIS EVENING FOR MDZ001.
OH...NONE.
PA...WINTER WEATHER ADVISORY UNTIL 4 PM EST THIS AFTERNOON FOR
PAZ074>076.
WV...WINTER STORM WARNING UNTIL 7 PM EST THIS EVENING FOR WVZ023-
041.
WINTER WEATHER ADVISORY UNTIL 4 PM EST THIS AFTERNOON FOR
WVZ021-022.
&&
$$
AREA FORECAST DISCUSSION
NWS PITTSBURGH PA
501 AM EST THU FEB 13 2014
.SYNOPSIS...
EAST COAST LOW PRESSURE WILL SPREAD SNOW TO AREAS EAST OF
INTERSTATE 79 TODAY BEFORE MOVING OFF TOWARDS NEW ENGLAND. A
SHORTWAVE WILL BRING THE CHANCE FOR ADDITIONAL SNOW FRIDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
DEFORMATION BAND OF HEAVY SNOW HAS MADE IT INTO
PRESTON...TUCKER...AND GARRETT COUNTIES THIS MORNING. EXPECT
SNOWFALL RATES EXCEEDING AN INCH AN HOUR AS THIS BAND MOVES
NORTHWARD. WITH SNOWFALL REPORTS ALREADY IN THE 3-4 INCH RANGE
OVER TUCKER AND GARRETT COUNTIES...HAVE SLIGHTLY BUMPED UP
SNOWFALL AMOUNTS. THE DRY SLOT SHOULD STILL DECREASE RATES BRIEFLY
THIS MORNING...AS IS ALREADY BEING SEEN ON THE NORTHERN FRINGE OF
THE PRECIP ON RADAR OVER OUR CWA. SNOW HAS STRUGGLED TO GO MUCH
FARTHER NORTH THAN THE VERY TIP OF ALLEGHENY COUNTY YET THIS
MORNING ALTHOUGH THE DETERMINISTIC MODEL AND THE HRRR CONTINUE TO
SUGGEST SOME LIGHT SNOW SHOULD MAKE IT TO PITTSBURGH.
AS THE NEGATIVELY TILTED TROUGH STRENGTHS THE COASTAL LOW...THE
TROWAL AND ENHANCED SNOWFALL SHOULD MOVE NORTH AND PIVOT ACROSS
THE COUNTIES EAST OF I79 THROUGH THE AFTERNOON. THE LOW WILL MOVE
TOWARD THE DELMARVA AND REACH LONG ISLAND BY THIS TONIGHT...TAKING
THE BULK OF THE MOISTURE WITH IT. SNOW SHOULD BEGIN TO TAPER OFF
BY THIS EVENING FROM WEST TO EAST. A BRIEF PERIOD OF FREEZING
DRIZZLE COULD BE POSSIBLE OVER THE RIDGES BEFORE A WEAK FRONT
ASSOCIATED WITH A SHORTWAVE CROSSING THE GREAT LAKES CROSSES THE
REGION OVERNIGHT.
DESPITE THE EASTERLY WINDS...TEMPERATURES SHOULD REACH CLOSE TO
FREEZING ACROSS MUCH OF THE REGION TODAY AND SHOULD NOT FALL TOO
MUCH UNTIL THE FRONTAL PASSAGE LATE TONIGHT.
&&
.SHORT TERM /FRIDAY THROUGH SATURDAY NIGHT/...
COLD ADVECTION MAY BRING THE CHANCE FOR SOME SNOW SHOWERS EARLY
FRIDAY BEFORE THE NEXT SHORTWAVE DIVES SOUTH TOWARD WEST VIRGINIA.
THE MODELS ARE HANDLING THIS SECOND SHORTWAVE BETTER THAN THE LAST
COUPLE OF NIGHTS...SUGGESTING THAT THE BULK OF THE MOISTURE WILL
STAY SOUTH OF I-70. FOR NOW...CARRIED THE HIGHEST POPS TO THE
SOUTH BUT MAINTAINED CHANCE FURTHER NORTH SINCE THE MODELS ARE
STILL TRYING TO SQUEEZE OUT SOME PRECIPITATION IN THE COLD
ADVECTION EARLY FRIDAY.
NORTHWEST FLOW MAY CONTINUE THE CHANCE FOR SOME SCATTERED SNOW
SHOWERS UP NORTH AND IN THE RIDGES ON SATURDAY BUT WITH A LACK OF
MOISTURE AND THE FROZEN LAKE ERIE...VERY LITTLE ACCUMULATION IS
EXPECTED.
YET ANOTHER SHORTWAVE WILL DIVE TOWARD THE REGION LATE SATURDAY
NIGHT AND SUNDAY. THIS SYSTEM LOOKS TO BE RELATIVELY MOISTURE
STARVED SO VERY LIGHT ACCUMULATIONS WERE KEPT IN THE FORECAST.
TEMPERATURES CONTINUE TO TREND BELOW SEASONAL AVERAGES DUE TO THE
SERIES OF WAVES AND COLD ADVECTION.
&&
.LONG TERM /SUNDAY THROUGH WEDNESDAY/...
LONG RANGE MODELS ARE HAVING A DIFFICULT TIME HANDLING A COUPLE OF
QUICK MOVING SHORT WAVES IN THE SHORT TERM...WHICH TRANSLATES TO
GREATER DIFFERENCES IN THE EXTENDED PERIOD. ONE THING THAT IS
GENERALLY AGREED UPON IS A WARMUP TO AT LEAST NORMAL TEMPERATURES
NEXT WEEK. SOUTHWEST FLOW BETWEEN AN EXITING WEAK LOW SUN AND A
QUICK MOVING FRONT MON NIGHT WILL RESULT IN STRONG WAA WHICH
SHOULD LEAD TO RAIN BEING THE PRIMARY PRECIPITATION TYPE ALONG THE
FRONT. ELECTING TO KEEP POPS IN THE CHC RANGE FOR NOW AS
CONSIDERABLE TIMING DIFFERENCES BETWEEN THE EC/GFS EXIST.
HIGH PRESSURE BUILDS IN MID-WEEK WITH A RETURN TO SOUTHWEST FLOW
ALOFT...ULTIMATELY REINFORCING THE WARMING TREND.
&&
.AVIATION /09Z THURSDAY THROUGH MONDAY/...
CURRENT FORECAST KEEPS A FAIRLY SHARP EDGE TO THE EXPANSE OF SNOW
WITH THE MID-ATLANTIC SYSTEM THROUGH THURS. IFR SNOW EXPECTED IN MGW
AND LBE OVERNIGHT THROUGH MUCH OF THURS...WITH SEVERAL OTHER SITES
DROPPING TO MVFR CIGS...DEPENDING ON EXACTLY WHERE THE WESTERN
EDGE ENDS UP. FKL/ZZV SHOULD HAVE DRY CONDITIONS WITH
PREDOMINANTLY MID AND HIGH CLOUDS WITH THE SYSTEM REMAINING SO FAR
TO THE EAST. WINDS WILL KEEP AN EASTERLY COMPONENT THROUGH MID-MORNING
BEFORE GRADUALLY BACKING TO WESTERLY THURS NIGHT. WIND SPEED WILL
GENERALLY REMAIN LESS THAN 10 KTS THROUGHOUT.
.OUTLOOK..../THURSDAY NIGHT THROUGH MONDAY/...
PERIODIC RSTRNS ARE PSBL THROUGH THE EXTENDED FORECAST AS SVRL FAST
MOVG DISTURBANCES CROSS THE RGN.
&&
.PBZ WATCHES/WARNINGS/ADVISORIES...
MD...WINTER STORM WARNING UNTIL 7 PM EST THIS EVENING FOR MDZ001.
OH...NONE.
PA...WINTER WEATHER ADVISORY UNTIL 4 PM EST THIS AFTERNOON FOR
PAZ074>076.
WV...WINTER STORM WARNING UNTIL 7 PM EST THIS EVENING FOR WVZ023-
041.
WINTER WEATHER ADVISORY UNTIL 4 PM EST THIS AFTERNOON FOR
WVZ021-022.
&&
$$
AREA FORECAST DISCUSSION
NWS KANSAS CITY/PLEASANT HILL MO
303 AM CST Thu Feb 13 2014
.SHORT TERM...(Today through Friday)
Issued at 301 AM CST THU FEB 13 2014
Primary forecast challenge during the next 36 hours will be
precipitation chances late tonight into late Friday morning. Water
vapor imagery shows a well-defined upper disturbance currently
moving onshore over southern British Columbia. This upper wave will
quickly move southeastward and arrive at the forecast area by late
tonight as the upper trough begins to amplify. A moderate spread
remains with model output, primarily owing to the degree of
saturation below H85. Overall low-level moisture remains limited and
will be a mitigating factor for more impressive precipitation
potential, however strong large scale ascent is expected during the
approach/passage of the wave. Forecast soundings suggest mainly a
snow event assuming sufficient saturation does occur. The highest
probability of measurable snowfall will reside across the northeast
quarter of the forecast area. Total snowfall amounts in this area
will average one-half inch with some isolated locations near
Kirksville possibly experiencing near an inch. Again, modest
uncertainty remains to the degree of low-level saturation that can
be obtained, and snow amounts may vary pending this variable.
Snowfall is expected to move east of the area by Friday afternoon.
As for temperatures, maximum readings this afternoon remain somewhat
uncertain due to the degree of modification from the existing snow
pack. Trended conservative for afternoon readings, with lower to
middle 40s in most locations. Temperatures will be a little cooler
on Friday, but the southwest half of the forecast area should exceed
the freezing mark as skies become mostly clear following the passage
of the upper wave.
.LONG TERM...(Friday Night through Wednesday)
Issued at 301 AM CST THU FEB 13 2014
Above normal temperatures are still expected for the weekend ahead
and much of next week. Most snow cover should be eliminated this
weekend and low-level ridging will build into the area in between
clipper systems, allowing temperatures to reach the mid to upper 40s
on Saturday and Sunday, and the 50s early next week to possibly
lower 60s by midweek. Light snow remains possible for Saturday over
far northern and northeast Missouri as one of the clipper systems
drops through central and eastern IA, but any accumulations should
be fairly light and confined to the northeast corner of the forecast
area. Light rain showers are also possible on Monday as shortwave
trough pushes through the central CONUS, and another round of
showers with some potential for a few rumbles of thunder are
possible Thursday as cold front sweeps eastward across the region.
&&
.AVIATION...(For the 06Z TAFS through 06Z Midnight Friday)
Issued at 1105 PM CST WED FEB 12 2014
No changes to previous forecast. Sub 2Kft MVFR ceilings persist
across the terminals this evening, with surface observations showing
a break just west of FNB and TOP. RUC13 model 925mb RH maintains the
stratus through around 09Z and this advects it east of the
terminals, in line with previous TAF.
Otherwise, VFR conditions will return with mid cloud cover
persisting. Light and variable winds will trend light
south-southwest later on and then increase from the southwest at
10-12 knots by midday. Winds will ease toward the west by 00Z and
diminish.
With temperatures expected to climb into the 40s, considerable
snowmelt may occur tomorrow, perhaps settings up the stage for
radiation fog if clear skies and light winds permit. Have introduced
IFR visibilities after 03Z in the outlook period as a hedge in this
direction.
&&
.EAX WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
MO...NONE.
&&
$$
SHORT TERM...Blair
LONG TERM...Laflin
AVIATION...Bookbinder
AREA FORECAST DISCUSSION
NWS KANSAS CITY/PLEASANT HILL MO
1110 PM CST WED FEB 12 2014
.SHORT TERM...(This Evening through Saturday Afternoon)
Issued at 338 PM CST WED FEB 12 2014
Very fast northwest flow aloft will dominate the upper flow west of
the Mississippi River through Saturday. There will be no fewer than
3 clipper type systems which will be embedded within this flow and
will pass close or through the CWA during this period. And the long
awaited thaw, which normally comes in January, will finally arrive.
In the very short term a shortwave trough will exit the CWA this
evening on its way towards enhancing the winter storm which is
ongoing over the southeastern U.S. A weak cold front currently over
northwest MO will likely fall apart over the CWA tonight. This will
present a forecast challenge as a band of low clouds has followed
the passage of this front. With very weak winds behind the front
plus some residual moisture from today`s snowmelt it`s possible
these low clouds will linger well into the night...and thus keep
temperatures from falling too far.
First in the series of clipper systems will pass through the Dakotas
and MN tonight/Thursday. Pressure falls east of the Rockies will
allow moderately strong warm air advection to spread through the
region tomorrow and allow above freezing temperatures. The extensive
and deep snow cover plus increasing high level clouds will temper
the warmup but highs in the 40s seem reasonable for most.
A stronger system will track further south Thursday night and Friday
and bring a good chance for precipitation to at least the northeast
half of the CWA. Models are all on the same page but with some
timing differences. The combination of an increasing NW-SE oriented
baroclinic zone over the CWA with a deepening upper system justifies
increasing PoPs this area with measurable snowfall likely. Have gone
conservative on snow amounts with this package but one could argue
for somewhat higher amounts due to the strength of the warm air
advection. The frontal boundary associated with this system will
likely pass through the CWA on Friday and knock temperatures back
down below seasonal averages.
The third clipper system will arrive for the start of the weekend
but pass further north than Fridays system. Another surge of warm
air advection south of this upper system will result in a warm front
lifting northeast through the CWA during the day. Should be able to
wring out some elevated precipitation northeast of this boundary
with most of the precipitation falling north and east of the CWA.
Most favorable region in the CWA for chance PoPs will be over the
northeastern counties with snow the most likely precipitation type.
.LONG TERM...(Saturday Evening through Wednesday)
Issued at 338 PM CST WED FEB 12 2014
Conditions continue to look favorable for a period of warm weather
for our section of the country. The break down of the ridge over the
West Coast recently will allow a more zonal like flow to develop
across the nation during this period. While significant troughs are
still moving through the adjusted flow, the Polar express that has
been feeding the center of the country with Arctic air will take some
time off. Therefore, the warming trend that is beginning this week
will persist into next week, with the occasional dip in temperatures
as fast moving shortwave troughs zip through the flattened flow
across the nation.
Confidence in the overall upward trend in temperatures through next
week is rather high, though the specifics of those warmer
temperatures will be very hard to forecast with precision due to the
melting snow pack. This may introduce significant errors in forecast
highs for late in the weekend and early next work week. So,
confidence in above freezing, snow melting, weather is high with
readings ranging through the 40s and 50s for much of the next work
week, with a mid week appearance of 60s possible as advertised
850mb temperatures stay above zero. However, as a cautionary tail
that winter isn`t done yet, current models also advertise a return
of the highly amplified pattern just past the following weekend,
with a return of the cold Arctic air.
Otherwise, one of the troughs moving through will arrive in our
area Monday, and with the expectation of above freezing temperatures
current thoughts are that we might have some rain to start the next
work week. Rainfall amounts wont be very high however owing to poor
moisture from the Gulf, but every little bit will help.
&&
.AVIATION...(For the 06Z TAFS through 06Z Midnight Friday)
Issued at 1105 PM CST WED FEB 12 2014
No changes to previous forecast. Sub 2Kft MVFR ceilings persist
across the terminals this evening, with surface observations showing
a break just west of FNB and TOP. RUC13 model 925mb RH maintains the
stratus through around 09Z and this advects it east of the
terminals, in line with previous TAF.
Otherwise, VFR conditions will return with mid cloud cover
persisting. Light and variable winds will trend light
south-southwest later on and then increase from the southwest at
10-12 knots by midday. Winds will ease toward the west by 00Z and
diminish.
With temperatures expected to climb into the 40s, considerable
snowmelt may occur tomorrow, perhaps settings up the stage for
radiation fog if clear skies and light winds permit. Have introduced
IFR visibilities after 03Z in the outlook period as a hedge in this
direction.
&&
.EAX WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
MO...NONE.
&&
$$
SHORT TERM...MJ
LONG TERM...Cutter
AVIATION...Bookbinder
AREA FORECAST DISCUSSION
NWS GLASGOW MT
904 PM MST FRI FEB 14 2014
.SHORT TERM...FOR NORTHEAST MONTANA...TONIGHT THROUGH SUNDAY...
THE PRECIPITATION AREA THAT PUSHED THROUGH GLASGOW EARLIER HAD
SOME SLEET MIXED IN WITH THE LIGHT SNOW THAT FELL. GIVEN THE HIGH
IMPACT NATURE OF FREEZING RAIN/SLEET DECIDED TO KEEP THE CURRENT
FREEZING RAIN ADVISORY UNCHANGED. THE LATEST HRRR REFLECTS SOME
POTENTIAL FOR ADDITIONAL PRECIPITATION DEVELOPMENT ACROSS GARFIELD
COUNTY LATE THIS EVENING...THUS KEPT THEIR ADVISORY GOING AS WELL.
OTHERWISE THE BIGGEST CHANGE MADE WITH THIS EVENINGS UPDATE WAS TO
TREND UP TEMPS A BIT GIVEN A WARM EVENING SO FAR. GILCHRIST
MOIST PACIFIC FLOW WILL SEND A COUPLE OF DISTURBANCES ACROSS THE
AREA DURING THIS PERIOD. THE FIRST ONE COMES THROUGH THIS
EVENING...THE SECOND LATE SATURDAY NIGHT AND SUNDAY MORNING.
THIS FIRST SYSTEM SHOULD RAPIDLY SPREAD PRECIP EAST ACROSS THE CWA
THIS EVENING. TEMPERATURE PROFILES WILL BE IN PLACE FOR FREEZING
RAIN NEAR HIGHWAY 2 AND SOUTH. THE GREATEST POTENTIAL LOOKS TO BE
IN PLACES WHERE THE TEMPERATURE DIDN/T REACH 32F TODAY. SO HIGHWAY
2 FROM GLASGOW TO WOLF POINT LOOKS TO UNDER THE GREATEST THREAT.
BUT AMOUNTS SHOULD BE LIGHT SO GLAZED ROADWAYS AND SIDEWALKS WILL
BE THE GREATEST IMPACTS.
CLEARING SKIES FOLLOW IN THE WAKE OF THE SYSTEM LATE TONIGHT/SATURDAY
MORNING. THE NEXT SYSTEM THEN AFFECTS THE AREA WITH LIGHT PRECIP
AMOUNTS BUT ONCE AGAIN...TEMPERATURE PROFILES SUPPORT FREEZING
RAIN FOR MOST OF THE AREA. HIGHLIGHTS MAY BE NEEDED FOR THIS ONE
AS WELL. ANY ICY CONDITIONS SHOULDN/T LAST TOO LONG AS DECENT
MIXING ON SUNDAY SHOULD MELT THINGS OFF AS TEMPS REACH AT LEAST
THE UPPER 30S ACROSS NORTHEAST MONTANA. TFJ
.LONG TERM...SUNDAY NIGHT THROUGH FRIDAY...
GIVEN THE VERY GOOD MODEL CONSENSUS THROUGH THURSDAY...DECIDED TO
UPDATE THE LONG TERM FORECAST GRIDS THROUGH THAT TIME AND TRIED TO
ADD SOME VALUE AND A LITTLE MORE DETAIL. AFTER THURSDAY THERE
SEEMS TO STILL BE TOO MUCH DISAGREEMENT...KEEPING FORECAST
CONFIDENCE LOW FOR NEXT WEEKEND.
EXPECT A NEARLY ZONAL FLOW PATTERN SUNDAY NIGHT THROUGH LATE
TUESDAY NIGHT...KEEPING THE WEATHER FOR NORTHEAST MONTANA DRY.
STARTING WEDNESDAY MORNING THE FLOW PATTERN BEGINS TO SHIFT TO A
MORE AMPLIFIED ONE WITH COLDER TEMPERATURES AND BETTER CHANCES FOR
SNOW. BMICKELSON
PREVIOUS LONG TERM DISCUSSION...EXTENDED FORECAST BEGINS MILD
WITH TEMPERATURES 10 DEGREES ABOVE NORMAL...AND DRY UNTIL
WEDNESDAY WHEN A SHORTWAVE...DEPICTED NEARLY IDENTICALLY IN THE EC
AND GFS MODELS...TRACKING ALONG THE US- CANADIAN BORDER BRINGS A
WARM FRONT UP THROUGH THE AREA. PPT TYPE ON WEDNESDAY MIGHT BE
TRICKY WITH A CHANCE FOR RAIN...SNOW OR FREEZING RAIN/DRIZZLE...AS
WOULD BE TYPICAL OF A WARM FRONT...THOUGH FORECAST SOUNDINGS
MOSTLY SUPPORT SNOW AT THIS POINT.
WEDNESDAY SYSTEM IS FOLLOWED BY A COLD FRONT WEDNESDAY NIGHT ON THE
BACK SIDE OF THE LOW WHICH DRAWS QUITE A SLUG OF COLD AIR DOWN
FROM CANADA CREATING SOME WRAP AROUND SNOW SHOWERS AND DROPPING
TEMPERATURES THURSDAY...FRIDAY AND BEYOND BACK TO 10 TO 20 DEGREES
BELOW NORMAL. COLD AIR MOVE THURSDAY IS PART OF THE DEVELOPMENT OF
A LONG WAVE TROUGH OVER MUCH OF THE CENTRAL US LATE NEXT WEEK.
MARTIN
&&
.AVIATION...
A BAND OF SNOW MIXED WITH JUST A LITTLE BIT OF FREEZING RAIN/SLEET IS
EXPECTED TO IMPACT ALL TAF SITES ROUGHLY FROM 02Z TO 08Z. CONDITIONS
MAY DETERIORATE TO MVFR AND BRIEFLY IFR FROM TIME TO TIME. WINDS
SHOULD BE A NON- ISSUE. EXPECT CLEARING SKIES AND VFR TO RETURN
BETWEEN 09Z AND 12Z. BMICKELSON/AEC
&&
.GLASGOW WATCHES/WARNINGS/ADVISORIES...
FREEZING RAIN ADVISORY UNTIL 3 AM MST SATURDAY FOR CENTRAL AND
SOUTHERN VALLEY...DAWSON...EASTERN ROOSEVELT...GARFIELD...
MCCONE...PRAIRIE...RICHLAND...WESTERN ROOSEVELT...WIBAUX.
&&
$$
WEATHER.GOV/GLASGOW
AREA FORECAST DISCUSSION
NWS GREAT FALLS MT
855 PM MST Fri Feb 14 2014
.DISCUSSION...
Update forthcoming as a few changes have been made. Winds along the
Rocky Mountain Front have decreased. Gusts to 40 or 45 mph are still
possible for the next few hours but RUC analysis continues to
indicate 700 mb winds will decrease overnight. Therefore, have
canceled the High Wind warning. Radar returns indicate snow
continuing to fall over the Rocky Mountain Front and, to a lesser
extent, the mountains of southwest Montana so will allow the winter
weather highlights to ride. Have lowered pops across most of the
Hi-Line for the remainder of the evening. Temperatures look good.
&&
.AVIATION...
UPDATED 2338Z.
An upper level high pressure ridge covers the western U.S. with
several embedded weather disturbances pushing through Montana during
the period causing winds to increase across the Northern Rockies and
most of north central Montana. Areas of snow showers are possible as
these disturbances push through...mainly over the northern Rockies
and mountains of southwest Montana...early in the period with a
chance for MFR conditions near the snow showers. Conditions will
improve Saturday morning and early afternoon...with increasing
cloudiness as the next disturbance approaches from the west.
&&
.PREV DISCUSSION...ISSUED 244 PM MST Fri Feb 14 2014
Tonight through Sunday...Windy conditions will continue through
this evening over portions of North Central MT as an upper level
disturbance continues to move through the region.
Additionally...the westerly flow is allowing for snow to fall over
the Rocky Mountain Front and portions of Southwest MT. The best
snow accumulations will fall in the mountains...but a few mountain
pass roadways could be impacted through the evening hours...thus
the advisory will continue. The next change was to add a high wind
watch for all of North Central MT for late Saturday night through
Sunday night. Both the NAM/GFS continue to prog a fairly strong
wind event over much of the region...thus the watch has been
issued. There will continue to be a small chance for precip at
lower elevations over the weekend and a good chance for precip in
the mountains. At this time I held off on mentioning the potential
for freezing rain on Sunday as the westerly flow should keep the
precip either just rain or snow...however this will be watched
closely. Temperatures will continue to run a few degrees above
normal for most areas through the weekend. Brusda
Sunday night through Friday...A generally moist and unsettled
pattern will persist over the region through most of the forecast
period. Westerly flow brings dry conditions to the plains and
precipitation to the Continental Divide into Tuesday. A low pressure
system with ample Pacific moisture and associated cold front move
across Montana Tuesday night into Wednesday bringing accumulating
mountain snowfall to elevations above 5000 feet, with rain/snow mix
possible at lower elevations. Models remain in agreement that a
very unsettled period will linger Tuesday through Thursday as
multiple disturbance bring precipitation to various parts of Central
Montana. Timing and location of precipitation during this period is
somewhat poorly agreed upon; standard for a pattern of this nature.
In the wake of a secondary front passing Thursday, cold air will
move in from the north. Temperatures will drop noticeably but do not
look to go much below zero at this time. Overall temperatures will
remain warm into Wednesday before beginning a downward trend into
the weekend. With a moist and unstable pattern expected, POP was
raised quite a bit over the mountains, with valleys to a lesser
extent, during almost the entire long term forecast.
&&
.PRELIMINARY POINT TEMPS/POPS...
GTF 30 46 35 45 / 20 10 20 20
CTB 27 43 30 41 / 20 10 30 20
HLN 28 47 32 46 / 30 20 30 30
BZN 22 45 30 45 / 40 20 30 40
WEY 20 37 25 36 / 100 60 90 80
DLN 25 46 31 42 / 50 30 40 50
HVR 27 41 29 45 / 20 0 30 20
LWT 28 42 32 42 / 20 0 30 20
&&
.TFX WATCHES/WARNINGS/ADVISORIES...
HIGH WIND WATCH from late Saturday night through late Sunday
night Blaine...Cascade...Chouteau...Eastern Glacier...Eastern
Pondera...Eastern Teton...Fergus...Hill...Judith Basin...
Liberty...Northern Rocky Mountain Front...Southern Rocky
Mountain Front...Toole.
WINTER WEATHER ADVISORY until 5 AM MST Saturday Beaverhead...
Gallatin...Madison.
WINTER WEATHER ADVISORY until 5 AM MST Saturday Northern Rocky
Mountain Front...Southern Rocky Mountain Front.
&&
$$
weather.gov/greatfalls
www.twitter.com/NWSGreatFalls
www.facebook.com/US.NationalWeatherService.GreatFalls.gov
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
325 PM EST THU FEB 13 2014
.SYNOPSIS...
SNOW WILL CONTINUE TONIGHT AS LOW PRESSURE MOVES UP THE EAST COAST.
THE SNOW WILL TAPER OFF LATE TONIGHT OR ON FRIDAY MORNING. A
SERIES OF CLIPPERS WILL BRING PERIODS OF SNOW SHOWERS AS THESE
SYSTEMS MOVE THROUGH THE REGION.
&&
.NEAR TERM /THROUGH FRIDAY/...
330 PM UPDATE... WE`VE EXPANDED WINTER STM WARNINGS ACRS NRN PTNS
OF THE CWA...BASICALLY BACK WESTWARD TO ABT THE I-81 CORRIDOR.
WARNINGS NOW EXTEND ALG AND E OF A LN FROM ONONDAGA-CORTLAND-
BROOME-SUSQ-WYOMING-LUZERNE CNTYS...WITH ADVSYS W OF THIS LN THRU
THE FINGER LKS AND CNTRL SRN TIER RGNS.
WATER VAPOR IMAGERY AND UPR AIR/MESO-ANALYSIS DATA DEPICT A
DEEPENING AND CLOSED 700-500 MB LOW OVER VA ATTM...LIFTING
NEWD...WITH AN AREA OF COOLING CLOUD TOPS/INCREASING RADAR
COVERAGE ACRS ERN WV/VA. IN THE MEANTIME...A WELL DEFINED NARROW
SNOW BAND EXTENDS FROM CNTRL PA...NEWD TO KBGM...TO JUST S OF
KALY...AND INTO CNTRL NEW ENG. THE 13-KM RUC MODEL HAS BEEN
HANDLING THE EVOLUTION OF EACH OF THESE FEATURES WELL SO FAR
TDY...AND WE`VE LEANED HEAVILY ON ITS OUTPUT GOING FORWARD...WITH
SOME SUPPORT NOW INDICATED FROM THE 12Z EC...CANADIAN...AND LOCAL
WRF MODELS.
WE EXPECT THE MAIN SNOW BAND OVER CNY ATTM TO SLOW ITS WWD
PROGRESS THROUGH THIS EVE AND BROADEN OUT...IN RESPONSE TO THE
APPROACH OF THE CLOSED MID TO UPPER-LVL LOW FROM THE S. A NARROW
BAND OF FAIRLY HEAVY SNOW IS LIKELY TO DVLP THIS EVE (00-06Z)
UNDERNEATH STG MID-LYR FGEN FORCING...ON THE NRN/WRN SIDES OF THE
700-500 MB LOW. ALTHOUGH THE EXACT LOCATION OF THIS FUTURE HEAVIER
SNOW BAND IS SOMEWHAT UNCERTAIN...THE MOST LIKELY POSITION IS JUST
E OF THE I-81 CORRIDOR (FROM NE PA INTO ERN BROOME/ERN CHENANGO
CNTYS...AND THE WRN CATSKILLS). AS THE CLOSED MID-UPR LVL
CIRCULATION LIFTS FURTHER INTO NEW ENG AFTER 06Z...THE
STEADIEST/HVYST SNOWFALL SHOULD EXIT THE RGN FROM SW TO NE. BY
ARND DAYBREAK...THIS EVENT SHOULD BE OVER FOR OUR CWA.
ON FRI...A NRN STREAM S/WV...SEEN ON SAT IMAGERY OVER UPR MI/NRN
WI ATTM...IS PROGGED TO SWEEP ACRS THE RGN. ALTHOUGH THIS SYSTEM
WILL ACT AS A "KICKER" TO MOVE OUR PRESENT STORM FURTHER AWAY INTO
THE N ATLANTIC...IT WILL ALSO HELP BRING SOME LIGHTER SNOW
SHWRS/FLRYS BACK OVER CNY/NE PA...WITH AREAS SE OF LK ONT SEEING
A BIT OF LAKE ENHANCEMENT...WITHIN NWLY LOW-LVL FLOW. ANY ADDTNL
SNOWFALL AMTS ON FRI SHOULD BE LIGHT.
&&
.SHORT TERM /FRIDAY NIGHT THROUGH SUNDAY/...
SERIES OF CLIPPERS WILL MOVE ACROSS THE REGION...ONE FRI NGT/SAT
MRNG AND ANOTHER FOR SUNDAY. MAY SEE MINOR ACCUMS ACRS NE PA ON
SAT NGT. LAKE RESPONSE BEHIND THESE CLIPPERS PER FCST PROFILES SUGGESTS
WEAK/MINOR LES EVENTS. GIVEN TDA`S FOCUS ON SHORT TERM...WILL
TAKE A CLOSER LOOK AT THIS POTNL WITH LATER FCSTS.
&&
.LONG TERM /SUNDAY NIGHT THROUGH WEDNESDAY/...
A SUBTLE PATTERN CHANGE ACROSS THE NORTHERN HEMISPHERE IS
EXPECTED TO TAKE PLACE DURING THIS PERIOD WITH LOWER HEIGHTS
DEVELOPING OVER THE PACIFIC NORTHWEST AND A BROADENING OF THE FLOW
TO QUASI-ZONAL ACROSS THE REST OF THE CONUS. THIS SUGGESTS A
GRADUAL WARM UP WILL TAKE PLACE DURING THE WEEK WITH RATHER RAPID
TRANSITING SYSTEMS MOVING THROUGH THE REGION. A COUPLE QUICK HITTING
FRONTAL SYSTEMS ARE EXPECTED DURING THE MON NITE-TUES AND THEN
AGAIN THURS NITE-FRI TIME PERIOD. THE FIRST SYSTEM SHOULD BE
MAINLY SNOW...WITH A WINTRY MIX TO RAIN EVENT POSSIBLE WITH THE
LATTER SYSTEM.
TEMPERATURES WILL GRADUALLY WARM UP THROUGH MID WEEK...THEN CLIMB
WELL INTO THE 40S THURSDAY AS SOUTHWEST FLOW DEEPENS ACROSS THE
EAST. THE WX SYSTEMS WILL BE MINOR...BUT THE MILDER TEMPERATURES
ARE EXPECTED TO RIPEN AND MELT A SUBSTANTIAL AMOUNT OF THE
EXISTING SNOW PACK WITH AREA RIVERS RESPONDING TO THE RUNOFF.
&&
.AVIATION /20Z THURSDAY THROUGH TUESDAY/...
LOW PRESSURE MOVING NORTH ALONG THE ATLANTIC SEABOARD WILL REACH
THE NEW ENGLAND COASTAL WATERS TONIGHT. WIDESPREAD IFR IN SNOW
WILL CONTINUE OVER THE CNY/NEPA TERMINALS THROUGH THIS EVENING.
EMBEDDED HEAVIER BANDS OF SNOW ARE EXPECTED TO AFFECT KAVP AND
PROBABLY KBGM WITH FLIGHT RESTRICTIONS BELOW AIRPORT MINIMA LIKELY
AT TIMES THIS AFTERNOON. KAVP MAY BRIEFLY IMPROVE AS PRECIP
DIMINISHES BENEATH A SEGMENT OF DRIER AIR WORKING NORTHWARD.
THE NORTHWEST EXTENT OF HEAVIER SNOW AND STRICTER FLIGHT RESTRICTIONS
ELSEWHERE IS THE LESS CONFIDENT PART OF THE FORECAST FOR LATE
TODAY AND THIS EVENING. THERE SEEM TO BE HINTS IN MODEL GUIDANCE
THAT THE STORM WILL SET UP AN AXIS OF HEAVIER SNOW AFFECTING KELM-
KBGM-KITH AND KAVP AGAIN DURING THE 23Z-03Z TIME FRAME...THEN
TRANSLATE LATER TONIGHT INTO KSYR-KRME WHERE AIRPORT MINIMA WILL
BE CHALLENGED.
AS DAWN ARRIVES FRIDAY...THE SNOW INTENSITY WILL RAPIDLY DIMINISH
WITH CONDITIONS IMPROVING THROUGH MVFR AND VFR CATEGORIES BY 18Z
FRIDAY.
WINDS GENERALLY NORTHEAST 5-10 KTS THIS AFTERNOON (WITH SOME LOCAL
VARIATIONS WHERE WINDS ARE LIGHT)...BECOMING NORTH-NORTHWEST
TONIGHT AND INCREASING 10-20 KTS AND BECOMING GUSTY. WINDS THEN
TREND MORE WESTERLY ON FRIDAY MORNING...REMAINING GUSTY TO 25 KTS.
OUTLOOK...
FRI AFTERNOON...VFR.
FRI NGT...BECOMING IFR IN -SN WITH LOW PRESSURE PASSING TO THE SOUTH.
SAT/SUN...VARIABLE VMC/IMC IN LAKE EFFECT SNOW SHOWERS.
SUN NGT...VFR.
MON...BECOMING MVFR. CHC WINTRY MIX.
TUE...VFR/MVFR.
&&
.BGM WATCHES/WARNINGS/ADVISORIES...
PA...WINTER STORM WARNING UNTIL 10 AM EST FRIDAY FOR PAZ039-040-043-
044-047-048-072.
WINTER WEATHER ADVISORY UNTIL 10 AM EST FRIDAY FOR PAZ038.
NY...WINTER STORM WARNING UNTIL 10 AM EST FRIDAY FOR NYZ009-018-036-
037-044>046-056-057-062.
WINTER WEATHER ADVISORY UNTIL 10 AM EST FRIDAY FOR NYZ015>017-
022>025-055.
&&
$$
SYNOPSIS...
NEAR TERM...MLJ
SHORT TERM...
LONG TERM...JAB
AVIATION...JAB
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
252 PM EST THU FEB 13 2014
.SYNOPSIS...
SNOW WILL CONTINUE TONIGHT AS LOW PRESSURE MOVES UP THE EAST COAST.
THE SNOW WILL TAPER OFF LATE TONIGHT OR ON FRIDAY MORNING. A
SERIES OF CLIPPERS WILL BRING PERIODS OF SNOW SHOWERS AS THESE
SYSTEMS MOVE THROUGH THE REGION.
&&
.NEAR TERM /THROUGH FRIDAY/...
830 AM UPDATE...
SNOW PUSHING NWD INTO CNTRL NY THIS MRNG...WITH +SN LIKELY OVER
THE WRN CATSKILLS AND POCONOS LATE THIS MRNG AND EARLY AFTN. XPCT
LGT ACCUMS ACRS THE REMAINDER OF THE AREA TDA. AS THIS 1ST WAVE MOVS
OUT...UPR LVL LOW WILL MOV INTO THE RGN THIS EVNG TAKING ON A NEG
TILT. RUC13 DATA VERY INTERESTING FOR TNGT...ACTUALLY SHOWING A
CLOSED 700 MB CIRCULATION OVER ERN PA THIS EVNG...ALONG WITH DVLPG
N/S FGEN AXIS/DEF ZONE ACRS CNTRL/ERN ZONES AND OTHER SIGS VERY
SUGGESTIVE OF +SN ACRS THIS AREA TNGT. ONLY MINOR TWEEKS TO NEAR
TERM FCST. PREV BLO...
7AM UPDATE...
MINOR CHANGES TO THE ONSET. BIGGEST CHANGE TO THE QPF AND SNOW
AMOUNTS IN THE FAR SOUTH WHICH WERE LOWERED. DESPITE SNOWING FOR
HOURS THERE ASOSES REPORTING ONLY A FEW HUNDREDTHS. INCH THE
HIGHEST SNOW REPORT SO FAR. DRY AND COLD AIR STILL AT SURFACE IN
THE NORTH.
4 AM UPDATE...
CONTINUING WITH THE SAME WARNINGS AND ADVISORIES AS DAY SHIFT
ISSUED WED AFTN.
LIGHT SNOW ON TRACK NORTH INTO NE PA AND THE CATSKILLS. THE SNOW
WILL CONTINUE NORTH TO COVER THE REST OF THE CWA BY 3 PM. SNOW
WILL END FROM SW TO NE LATE TONIGHT. THE SNOW AHEAD OF A NOREASTER
BOMBING OFF OF NC NOW. THIS WILL SLOWLY TRACK NE ALONG THE COAST.
THE LOW WILL BE OVER CAPE COD AROUND MIDNIGHT. THE UPPER LEVELS
HAVE A CLOSED NEGATIVELY TILTED TROF SLIGHTLY BEHIND THE SFC LOW.
THE HEAVIEST PRECIP WILL BE EAST OF THE CWA. IN OUR AREA PRECIP
WILL BE ALL SNOW. THE WETTEST SNOW WILL BE IN THE FAR SE WHERE 850
TEMPS RISE -2C. ENOUGH TO LOWER RATIOS BUT STILL PLENTY OF QPF FOR
WARNING AMOUNTS. MOIST LOW LEVEL INFLOW OFF OF ATLANTIC SO THAT SE
CWA WILL HAVE QPF OF HALF TO ONE INCH. SHARP GRADIENT ACROSS THE
CWA SO THE FAR WEST WILL HAVE AROUND A TENTH OF AN INCH LIQUID AND
ONLY 1 TO 2 INCHES OF SNOW.
ON THE BACK SIDE TONIGHT QUESTIONS ON HOW STRONG THE WRAPAROUND
WILL BE AND WHERE. THE BIGGEST DUMPER OF SNOW WAS THE EURO IN THAT
RESPECT BUT IT HAS BACKED OFF SOME. BOTH IN QUANTITY AND DURATION.
EITHER WAY WITH THESE STORMS SNOW AMOUNTS WILL VARY WIDELY.
&&
.SHORT TERM /FRIDAY NIGHT THROUGH SUNDAY/...
SERIES OF CLIPPERS WILL MOVE ACROSS THE REGION...ONE FRI NGT/SAT
MRNG AND ANOTHER FOR SUNDAY. MAY SEE MINOR ACCUMS ACRS NE PA ON
SAT NGT. LAKE RESPONSE BEHIND THESE CLIPPERS PER FCST PROFILES SUGGESTS
WEAK/MINOR LES EVENTS. GIVEN TDA`S FOCUS ON SHORT TERM...WILL
TAKE A CLOSER LOOK AT THIS POTNL WITH LATER FCSTS.
&&
.LONG TERM /SUNDAY NIGHT THROUGH WEDNESDAY/...
A SUBTLE PATTERN CHANGE ACROSS THE NORTHERN HEMISPHERE IS
EXPECTED TO TAKE PLACE DURING THIS PERIOD WITH LOWER HEIGHTS
DEVELOPING OVER THE PACIFIC NORTHWEST AND A BROADENING OF THE FLOW
TO QUASI-ZONAL ACROSS THE REST OF THE CONUS. THIS SUGGESTS A
GRADUAL WARM UP WILL TAKE PLACE DURING THE WEEK WITH RATHER RAPID
TRANSITING SYSTEMS MOVING THROUGH THE REGION. A COUPLE QUICK HITTING
FRONTAL SYSTEMS ARE EXPECTED DURING THE MON NITE-TUES AND THEN
AGAIN THURS NITE-FRI TIME PERIOD. THE FIRST SYSTEM SHOULD BE
MAINLY SNOW...WITH A WINTRY MIX TO RAIN EVENT POSSIBLE WITH THE
LATTER SYSTEM.
TEMPERATURES WILL GRADUALLY WARM UP THROUGH MID WEEK...THEN CLIMB
WELL INTO THE 40S THURSDAY AS SOUTHWEST FLOW DEEPENS ACROSS THE
EAST. THE WX SYSTEMS WILL BE MINOR...BUT THE MILDER TEMPERATURES
ARE EXPECTED TO RIPEN AND MELT A SUBSTANTIAL AMOUNT OF THE
EXISTING SNOW PACK WITH AREA RIVERS RESPONDING TO THE RUNOFF.
&&
.AVIATION /20Z THURSDAY THROUGH TUESDAY/...
LOW PRESSURE MOVING NORTH ALONG THE ATLANTIC SEABOARD WILL REACH
THE NEW ENGLAND COASTAL WATERS TONIGHT. WIDESPREAD IFR IN SNOW
WILL CONTINUE OVER THE CNY/NEPA TERMINALS THROUGH THIS EVENING.
EMBEDDED HEAVIER BANDS OF SNOW ARE EXPECTED TO AFFECT KAVP AND
PROBABLY KBGM WITH FLIGHT RESTRICTIONS BELOW AIRPORT MINIMA LIKELY
AT TIMES THIS AFTERNOON. KAVP MAY BRIEFLY IMPROVE AS PRECIP
DIMINISHES BENEATH A SEGMENT OF DRIER AIR WORKING NORTHWARD.
THE NORTHWEST EXTENT OF HEAVIER SNOW AND STRICTER FLIGHT RESTRICTIONS
ELSEWEHRE IS THE LESS CONFIDENT PART OF THE FORECAST FOR LATE
TODAY AND THIS EVENING. THERE SEEM TO BE HINTS IN MODEL GUIDANCE
THAT THE STORM WILL SET UP AN AXIS OF HEAVIER SNOW AFFECTING KELM-
KBGM-KITH AND KAVP AGAIN DURING THE 23Z-03Z TIME FRAME...THEN
TRANSLATE LATER TONIGHT INTO KSYR-KRME WHERE AIRPORT MINIMA WILL
BE CHALLENGED.
AS DAWN ARRIVES FRIDAY...THE SNOW INTENSITY WILL RAPIDLY DIMINISH
WITH CONDITIONS IMPROVING THROUGH MVFR AND VFR CATEGORIES BY 18Z
FRIDAY.
WINDS GENERALLY NORTHEAST 5-10 KTS THIS AFTERNOON (WITH SOME LOCAL
VARIATIONS WHERE WINDS ARE LIGHT)...BECOMING NORTH-NORTHWEST
TONIGHT AND INCREASING 10-20 KTS AND BECOMING GUSTY. WINDS THEN
TREND MORE WESTERLY ON FRIDAY MORNING...REMAINING GUSTY TO 25 KTS.
OUTLOOK...
FRI AFTERNOON...VFR.
FRI NGT...BECOMING IFR IN -SN WITH LOW PRESSURE PASSING TO THE SOUTH.
SAT/SUN...VARIABLE VMC/IMC IN LAKE EFFECT SNOW SHOWERS.
SUN NGT...VFR.
MON...BECOMING MVFR. CHC WINTRY MIX.
TUE...VFR/MVFR.
&&
.BGM WATCHES/WARNINGS/ADVISORIES...
PA...WINTER STORM WARNING UNTIL 10 AM EST FRIDAY FOR PAZ039-040-043-
044-047-048-072.
WINTER WEATHER ADVISORY UNTIL 10 AM EST FRIDAY FOR PAZ038.
NY...WINTER STORM WARNING UNTIL 10 AM EST FRIDAY FOR NYZ009-018-036-
037-044>046-056-057-062.
WINTER WEATHER ADVISORY UNTIL 10 AM EST FRIDAY FOR NYZ015>017-
022>025-055.
&&
$$
SYNOPSIS...
NEAR TERM...
SHORT TERM...TAC
LONG TERM...JAB
AVIATION...JAB
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
225 PM EST THU FEB 13 2014
.SYNOPSIS...
SNOW IS SPREADING NORTH TODAY INTO NEW YORK. SNOW WILL CONTINUE
INTO TONIGHT THEN END LATE TONIGHT. FRIDAY AND SATURDAY LIGHT SNOW
SHOWERS ARE POSSIBLE ESPECIALLY IN CENTRAL NEW YORK.
&&
.NEAR TERM /THROUGH TONIGHT/...
830 AM UPDATE...
SNOW PUSHING NWD INTO CNTRL NY THIS MRNG...WITH +SN LIKELY OVER
THE WRN CATSKILLS AND POCONOS LATE THIS MRNG AND EARLY AFTN. XPCT
LGT ACCUMS ACRS THE REMAINDER OF THE AREA TDA. AS THIS 1ST WAVE MOVS
OUT...UPR LVL LOW WILL MOV INTO THE RGN THIS EVNG TAKING ON A NEG
TILT. RUC13 DATA VERY INTERESTING FOR TNGT...ACTUALLY SHOWING A
CLOSED 700 MB CIRCULATION OVER ERN PA THIS EVNG...ALONG WITH DVLPG
N/S FGEN AXIS/DEF ZONE ACRS CNTRL/ERN ZONES AND OTHER SIGS VERY
SUGGESTIVE OF +SN ACRS THIS AREA TNGT. ONLY MINOR TWEEKS TO NEAR
TERM FCST. PREV BLO...
7AM UPDATE...
MINOR CHANGES TO THE ONSET. BIGGEST CHANGE TO THE QPF AND SNOW
AMOUNTS IN THE FAR SOUTH WHICH WERE LOWERED. DESPITE SNOWING FOR
HOURS THERE ASOSES REPORTING ONLY A FEW HUNDREDTHS. INCH THE
HIGHEST SNOW REPORT SO FAR. DRY AND COLD AIR STILL AT SURFACE IN
THE NORTH.
4 AM UPDATE...
CONTINUING WITH THE SAME WARNINGS AND ADVISORIES AS DAY SHIFT
ISSUED WED AFTN.
LIGHT SNOW ON TRACK NORTH INTO NE PA AND THE CATSKILLS. THE SNOW
WILL CONTINUE NORTH TO COVER THE REST OF THE CWA BY 3 PM. SNOW
WILL END FROM SW TO NE LATE TONIGHT. THE SNOW AHEAD OF A NOREASTER
BOMBING OFF OF NC NOW. THIS WILL SLOWLY TRACK NE ALONG THE COAST.
THE LOW WILL BE OVER CAPE COD AROUND MIDNIGHT. THE UPPER LEVELS
HAVE A CLOSED NEGATIVELY TILTED TROF SLIGHTLY BEHIND THE SFC LOW.
THE HEAVIEST PRECIP WILL BE EAST OF THE CWA. IN OUR AREA PRECIP
WILL BE ALL SNOW. THE WETTEST SNOW WILL BE IN THE FAR SE WHERE 850
TEMPS RISE -2C. ENOUGH TO LOWER RATIOS BUT STILL PLENTY OF QPF FOR
WARNING AMOUNTS. MOIST LOW LEVEL INFLOW OFF OF ATLANTIC SO THAT SE
CWA WILL HAVE QPF OF HALF TO ONE INCH. SHARP GRADIENT ACROSS THE
CWA SO THE FAR WEST WILL HAVE AROUND A TENTH OF AN INCH LIQUID AND
ONLY 1 TO 2 INCHES OF SNOW.
ON THE BACK SIDE TONIGHT QUESTIONS ON HOW STRONG THE WRAPAROUND
WILL BE AND WHERE. THE BIGGEST DUMPER OF SNOW WAS THE EURO IN THAT
RESPECT BUT IT HAS BACKED OFF SOME. BOTH IN QUANTITY AND DURATION.
EITHER WAY WITH THESE STORMS SNOW AMOUNTS WILL VARY WIDELY.
&&
.SHORT TERM /FRIDAY THROUGH SUNDAY/...
4 AM UPDATE...
FRIDAY IN BETWEEN SYSTEMS WITH THE NOREASTER PULLING OUT AND A
CLIPPER COMING IN BEHIND IT WITH THE COLD AIR. FIRST LOW GETS
ABSORBED BY THE BOMB OVER SE CANADA. LIGHT SNOW MOSTLY FOR UPSTATE
NY. A SECOND LOW WILL PASS TO THE SOUTH AND BOMB OFF THE MID
ATLANTIC COAST SAT MORNING. THIS WILL SPREAD LIGHT SNOW INTO PA
BUT THE MAIN EVENT WILL BE EAST OF THE CWA.
WITH THE FIRST LOW FRIDAY MORNING LOW LEVEL WINDS SHIFT TO THE NW.
WITH THE MULTIPLE SHORT WAVES AND THE FALLING UL HEIGHTS LAKE
ENHANCEMENT LIKELY WITH SOME LIGHT ACCUMULATIONS. LL FLOW SHIFTS
TO THE W FRI AFTN SO THE SNOW SHIFTS TO MOSTLY ONEIDA. COLDER AIR
COMES IN SAT AND SAT NGT WHILE FLOW GOES BACK TO NW. AGAIN LIGHT
AMOUNTS EXPECTED. DECENT DENDRITE ZONE OF 3 TO 4 KT FEET IN THE
MOIST LAYER WHICH EXTENDS TO 8K FT. COLD AIR ONLY -12C WHICH IS
MARGINAL WITH THE COLD LAKE SFC TEMPS. LAKE EFFECT BUT WEAK AND
MULTIBANDS.
&&
.LONG TERM /SUNDAY NIGHT THROUGH THURSDAY/...
A SUBTLE PATTERN CHANGE ACROSS THE NORTHERN HEMISPHERE IS
EXPECTED TO TAKE PLACE DURING THIS PERIOD WITH LOWER HEIGHTS
DEVELOPING OVER THE PACIFIC NORTHWEST AND A BROADENING OF THE FLOW
TO QUASI-ZONAL ACROSS THE REST OF THE CONUS. THIS SUGGESTS A
GRADUAL WARM UP WILL TAKE PLACE DURING THE WEEK WITH RATHER RAPID
TRANSITING SYSTEMS MOVING THROUGH THE REGION. A COUPLE QUICK HITTING
FRONTAL SYSTEMS ARE EXPECTED DURING THE MON NITE-TUES AND THEN
AGAIN THURS NITE-FRI TIME PERIOD. THE FIRST SYSTEM SHOULD BE
MAINLY SNOW...WITH A WINTRY MIX TO RAIN EVENT POSSIBLE WITH THE
LATTER SYSTEM.
TEMPERATURES WILL GRADUALLY WARM UP THROUGH MID WEEK...THEN CLIMB
WELL INTO THE 40S THURSDAY AS SOUTHWEST FLOW DEEPENS ACROSS THE
EAST. THE WX SYSTEMS WILL BE MINOR...BUT THE MILDER TEMPERATURES
ARE EXPECTED TO RIPEN AND MELT A SUBSTANTIAL AMOUNT OF THE
EXISTING SNOW PACK WITH AREA RIVERS RESPONDING TO THE RUNOFF.
&&
.AVIATION /19Z THURSDAY THROUGH TUESDAY/...
LOW PRESSURE MOVING NORTH ALONG THE ATLANTIC SEABOARD WILL REACH
THE NEW ENGLAND COASTAL WATERS TONIGHT. WIDESPREAD IFR IN SNOW
WILL CONTINUE OVER THE CNY/NEPA TERMINALS THROUGH THIS EVENING.
EMBEDDED HEAVIER BANDS OF SNOW ARE EXPECTED TO AFFECT KAVP AND
PROBABLY KBGM WITH FLIGHT RESTRICTIONS BELOW AIRPORT MINIMA LIKELY
AT TIMES THIS AFTERNOON. KAVP MAY BRIEFLY IMPROVE AS PRECIP
DIMINISHES BENEATH A SEGMENT OF DRIER AIR WORKING NORTHWARD.
THE NORTHWEST EXTENT OF HEAVIER SNOW AND STRICTER FLIGHT RESTRICTIONS
ELSEWEHRE IS THE LESS CONFIDENT PART OF THE FORECAST FOR LATE
TODAY AND THIS EVENING. THERE SEEM TO BE HINTS IN MODEL GUIDANCE
THAT THE STORM WILL SET UP AN AXIS OF HEAVIER SNOW AFFECTING KELM-
KBGM-KITH AND KAVP AGAIN DURING THE 23Z-03Z TIME FRAME...THEN
TRANSLATE LATER TONIGHT INTO KSYR-KRME WHERE AIRPORT MINIMA WILL
BE CHALLENGED.
AS DAWN ARRIVES FRIDAY...THE SNOW INTENSITY WILL RAPIDLY DIMINISH
WITH CONDITIONS IMPROVING THROUGH MVFR AND VFR CATEGORIES BY 18Z
FRIDAY.
WINDS GENERALLY NORTHEAST 5-10 KTS THIS AFTERNOON (WITH SOME LOCAL
VARIATIONS WHERE WINDS ARE LIGHT)...BECOMING NORTH-NORTHWEST
TONIGHT AND INCREASING 10-20 KTS AND BECOMING GUSTY. WINDS THEN
TREND MORE WESTERLY ON FRIDAY MORNING...REMAINING GUSTY TO 25 KTS.
OUTLOOK...
FRI AFTERNOON...VFR.
FRI NGT...BECOMING IFR IN -SN WITH LOW PRESSURE PASSING TO THE SOUTH.
SAT/SUN...VARIABLE VMC/IMC IN LAKE EFFECT SNOW SHOWERS.
SUN NGT...VFR.
MON...BECOMING MVFR. CHC WINTRY MIX.
TUE...VFR/MVFR.
&&
.BGM WATCHES/WARNINGS/ADVISORIES...
PA...WINTER STORM WARNING UNTIL 10 AM EST FRIDAY FOR PAZ039-040-043-
044-047-048-072.
WINTER WEATHER ADVISORY UNTIL 10 AM EST FRIDAY FOR PAZ038.
NY...WINTER STORM WARNING UNTIL 10 AM EST FRIDAY FOR NYZ045-046-056-
057-062.
WINTER WEATHER ADVISORY UNTIL 10 AM EST FRIDAY FOR NYZ009-017-
018-024-025-036-037-044-055.
&&
$$
SYNOPSIS...TAC
NEAR TERM...TAC
SHORT TERM...TAC
LONG TERM...JAB
AVIATION...JAB
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
101 PM EST THU FEB 13 2014
.SYNOPSIS...
SNOW IS SPREADING NORTH TODAY INTO NEW YORK. SNOW WILL CONTINUE
INTO TONIGHT THEN END LATE TONIGHT. FRIDAY AND SATURDAY LIGHT SNOW
SHOWERS ARE POSSIBLE ESPECIALLY IN CENTRAL NEW YORK.
&&
.NEAR TERM /THROUGH TONIGHT/...
830 AM UPDATE...
SNOW PUSHING NWD INTO CNTRL NY THIS MRNG...WITH +SN LIKELY OVER
THE WRN CATSKILLS AND POCONOS LATE THIS MRNG AND EARLY AFTN. XPCT
LGT ACCUMS ACRS THE REMAINDER OF THE AREA TDA. AS THIS 1ST WAVE MOVS
OUT...UPR LVL LOW WILL MOV INTO THE RGN THIS EVNG TAKING ON A NEG
TILT. RUC13 DATA VERY INTERESTING FOR TNGT...ACTUALLY SHOWING A
CLOSED 700 MB CIRCULATION OVER ERN PA THIS EVNG...ALONG WITH DVLPG
N/S FGEN AXIS/DEF ZONE ACRS CNTRL/ERN ZONES AND OTHER SIGS VERY
SUGGESTIVE OF +SN ACRS THIS AREA TNGT. ONLY MINOR TWEEKS TO NEAR
TERM FCST. PREV BLO...
7AM UPDATE...
MINOR CHANGES TO THE ONSET. BIGGEST CHANGE TO THE QPF AND SNOW
AMOUNTS IN THE FAR SOUTH WHICH WERE LOWERED. DESPITE SNOWING FOR
HOURS THERE ASOSES REPORTING ONLY A FEW HUNDREDTHS. INCH THE
HIGHEST SNOW REPORT SO FAR. DRY AND COLD AIR STILL AT SURFACE IN
THE NORTH.
4 AM UPDATE...
CONTINUING WITH THE SAME WARNINGS AND ADVISORIES AS DAY SHIFT
ISSUED WED AFTN.
LIGHT SNOW ON TRACK NORTH INTO NE PA AND THE CATSKILLS. THE SNOW
WILL CONTINUE NORTH TO COVER THE REST OF THE CWA BY 3 PM. SNOW
WILL END FROM SW TO NE LATE TONIGHT. THE SNOW AHEAD OF A NOREASTER
BOMBING OFF OF NC NOW. THIS WILL SLOWLY TRACK NE ALONG THE COAST.
THE LOW WILL BE OVER CAPE COD AROUND MIDNIGHT. THE UPPER LEVELS
HAVE A CLOSED NEGATIVELY TILTED TROF SLIGHTLY BEHIND THE SFC LOW.
THE HEAVIEST PRECIP WILL BE EAST OF THE CWA. IN OUR AREA PRECIP
WILL BE ALL SNOW. THE WETTEST SNOW WILL BE IN THE FAR SE WHERE 850
TEMPS RISE -2C. ENOUGH TO LOWER RATIOS BUT STILL PLENTY OF QPF FOR
WARNING AMOUNTS. MOIST LOW LEVEL INFLOW OFF OF ATLANTIC SO THAT SE
CWA WILL HAVE QPF OF HALF TO ONE INCH. SHARP GRADIENT ACROSS THE
CWA SO THE FAR WEST WILL HAVE AROUND A TENTH OF AN INCH LIQUID AND
ONLY 1 TO 2 INCHES OF SNOW.
ON THE BACK SIDE TONIGHT QUESTIONS ON HOW STRONG THE WRAPAROUND
WILL BE AND WHERE. THE BIGGEST DUMPER OF SNOW WAS THE EURO IN THAT
RESPECT BUT IT HAS BACKED OFF SOME. BOTH IN QUANTITY AND DURATION.
EITHER WAY WITH THESE STORMS SNOW AMOUNTS WILL VARY WIDELY.
&&
.SHORT TERM /FRIDAY THROUGH SATURDAY NIGHT/...
4 AM UPDATE...
FRIDAY IN BETWEEN SYSTEMS WITH THE NOREASTER PULLING OUT AND A
CLIPPER COMING IN BEHIND IT WITH THE COLD AIR. FIRST LOW GETS
ABSORBED BY THE BOMB OVER SE CANADA. LIGHT SNOW MOSTLY FOR UPSTATE
NY. A SECOND LOW WILL PASS TO THE SOUTH AND BOMB OFF THE MID
ATLANTIC COAST SAT MORNING. THIS WILL SPREAD LIGHT SNOW INTO PA
BUT THE MAIN EVENT WILL BE EAST OF THE CWA.
WITH THE FIRST LOW FRIDAY MORNING LOW LEVEL WINDS SHIFT TO THE NW.
WITH THE MULTIPLE SHORT WAVES AND THE FALLING UL HEIGHTS LAKE
ENHANCEMENT LIKELY WITH SOME LIGHT ACCUMULATIONS. LL FLOW SHIFTS
TO THE W FRI AFTN SO THE SNOW SHIFTS TO MOSTLY ONEIDA. COLDER AIR
COMES IN SAT AND SAT NGT WHILE FLOW GOES BACK TO NW. AGAIN LIGHT
AMOUNTS EXPECTED. DECENT DENDRITE ZONE OF 3 TO 4 KT FEET IN THE
MOIST LAYER WHICH EXTENDS TO 8K FT. COLD AIR ONLY -12C WHICH IS
MARGINAL WITH THE COLD LAKE SFC TEMPS. LAKE EFFECT BUT WEAK AND
MULTIBANDS.
&&
.LONG TERM /SUNDAY THROUGH WEDNESDAY/...
3 AM UPDATE...COLD NORTHWEST FLOW SUNDAY MORNING MAY BRING
SCATTERED SNOW SHOWERS AND FLURRIES SOUTHEAST OF LAKE ONTARIO
FOLLOWED BY PARTLY TO MOSTLY SUNNY CONDITIONS BY AFTERNOON AS SFC
HIGH PRES BUILDS IN. HIGH PRES SUN NGT WITH GOOD RADIATIONAL
COOLING AND FRESH SNOW COVER...WILL LIKELY RESULT IN MINS WELL
BLO ZERO. THIS HIGH MOVS TO THE E CST BY MONDAY EVNG AS A CLIPPER
TYPE SYSTEM HEADS INTO THE ERN GTLAKES. THIS WILL BRING MORE PCPN
TO THE RGN MON NGT INTO TUE....SNOW TRANSITIONING TO A RA/SN MIX
OR PLAIN RAIN ON TUE. WEDNESDAY LOOKS DRY AND MILDER WITH SFC
HIGH PRES OVER THE MID ATLANTIC PROVING A SOUTHWEST MODERATING
FLOW.
&&
.AVIATION /18Z THURSDAY THROUGH TUESDAY/...
LOW PRESSURE MOVING NORTH ALONG THE ATLANTIC SEABOARD WILL REACH
THE NEW ENGLAND COASTAL WATERS TONIGHT. WIDESPREAD IFR IN SNOW
WILL CONTINUE OVER THE CNY/NEPA TERMINALS THROUGH THIS EVENING.
EMBEDDED HEAVIER BANDS OF SNOW ARE EXPECTED TO AFFECT KAVP AND
PROBABLY KBGM WITH FLIGHT RESTRICTIONS BELOW AIRPORT MINIMA LIKELY
AT TIMES THIS AFTERNOON. KAVP MAY BRIEFLY IMPROVE AS PRECIP
DIMINISHES BENEATH A SEGMENT OF DRIER AIR WORKING NORTHWARD.
THE NORTHWEST EXTENT OF HEAVIER SNOW AND STRICTER FLIGHT RESTRICTIONS
ELSEWEHRE IS THE LESS CONFIDENT PART OF THE FORECAST FOR LATE
TODAY AND THIS EVENING. THERE SEEM TO BE HINTS IN MODEL GUIDANCE
THAT THE STORM WILL SET UP AN AXIS OF HEAVIER SNOW AFFECTING KELM-
KBGM-KITH AND KAVP AGAIN DURING THE 23Z-03Z TIME FRAME...THEN
TRANSLATE LATER TONIGHT INTO KSYR-KRME WHERE AIRPORT MINIMA WILL
BE CHALLENGED.
AS DAWN ARRIVES FRIDAY...THE SNOW INTENSITY WILL RAPIDLY DIMINISH
WITH CONDITIONS IMPROVING THROUGH MVFR AND VFR CATEGORIES BY 18Z
FRIDAY.
WINDS GENERALLY NORTHEAST 5-10 KTS THIS AFTERNOON (WITH SOME LOCAL
VARIATIONS WHERE WINDS ARE LIGHT)...BECOMING NORTH-NORTHWEST
TONIGHT AND INCREASING 10-20 KTS AND BECOMING GUSTY. WINDS THEN
TREND MORE WESTERLY ON FRIDAY MORNING...REMAINING GUSTY TO 25 KTS.
OUTLOOK...
FRI AFTERNOON...VFR.
FRI NGT...BECOMING IFR IN -SN WITH LOW PRESSURE PASSING TO THE SOUTH.
SAT/SUN...VARIABLE VMC/IMC IN LAKE EFFECT SNOW SHOWERS.
SUN NGT...VFR.
MON...BECOMING MVFR. CHC WINTRY MIX.
TUE...VFR/MVFR.
&&
.BGM WATCHES/WARNINGS/ADVISORIES...
PA...WINTER STORM WARNING UNTIL 10 AM EST FRIDAY FOR PAZ039-040-043-
044-047-048-072.
WINTER WEATHER ADVISORY UNTIL 10 AM EST FRIDAY FOR PAZ038.
NY...WINTER STORM WARNING UNTIL 10 AM EST FRIDAY FOR NYZ045-046-056-
057-062.
WINTER WEATHER ADVISORY UNTIL 10 AM EST FRIDAY FOR NYZ009-017-
018-024-025-036-037-044-055.
&&
$$
SYNOPSIS...TAC
NEAR TERM...TAC
SHORT TERM...TAC
LONG TERM...RRM
AVIATION...JAB
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
838 AM EST THU FEB 13 2014
.SYNOPSIS...
SNOW IS SPREADING NORTH TODAY INTO NEW YORK. SNOW WILL CONTINUE
INTO TONIGHT THEN END LATE TONIGHT. FRIDAY AND SATURDAY LIGHT SNOW
SHOWERS ARE POSSIBLE ESPECIALLY IN CENTRAL NEW YORK.
&&
.NEAR TERM /THROUGH TONIGHT/...
830 AM UPDATE...
SNOW PUSHING NWD INTO CNTRL NY THIS MRNG...WITH +SN LIKELY OVER
THE WRN CATSKILLS AND POCONOS LATE THIS MRNG AND EARLY AFTN. XPCT
LGT ACCUMS ACRS THE REMAINDER OF THE AREA TDA. AS THIS 1ST WAVE MOVS
OUT...UPR LVL LOW WILL MOV INTO THE RGN THIS EVNG TAKING ON A NEG
TILT. RUC13 DATA VERY INTERESTING FOR TNGT...ACTUALLY SHOWING A
CLOSED 700 MB CIRCULATION OVER ERN PA THIS EVNG...ALONG WITH DVLPG
N/S FGEN AXIS/DEF ZONE ACRS CNTRL/ERN ZONES AND OTHER SIGS VERY
SUGGESTIVE OF +SN ACRS THIS AREA TNGT. ONLY MINOR TWEEKS TO NEAR
TERM FCST. PREV BLO...
7AM UPDATE...
MINOR CHANGES TO THE ONSET. BIGGEST CHANGE TO THE QPF AND SNOW
AMOUNTS IN THE FAR SOUTH WHICH WERE LOWERED. DESPITE SNOWING FOR
HOURS THERE ASOSES REPORTING ONLY A FEW HUNDREDTHS. INCH THE
HIGHEST SNOW REPORT SO FAR. DRY AND COLD AIR STILL AT SURFACE IN
THE NORTH.
4 AM UPDATE...
CONTINUING WITH THE SAME WARNINGS AND ADVISORIES AS DAY SHIFT
ISSUED WED AFTN.
LIGHT SNOW ON TRACK NORTH INTO NE PA AND THE CATSKILLS. THE SNOW
WILL CONTINUE NORTH TO COVER THE REST OF THE CWA BY 3 PM. SNOW
WILL END FROM SW TO NE LATE TONIGHT. THE SNOW AHEAD OF A NOREASTER
BOMBING OFF OF NC NOW. THIS WILL SLOWLY TRACK NE ALONG THE COAST.
THE LOW WILL BE OVER CAPE COD AROUND MIDNIGHT. THE UPPER LEVELS
HAVE A CLOSED NEGATIVELY TILTED TROF SLIGHTLY BEHIND THE SFC LOW.
THE HEAVIEST PRECIP WILL BE EAST OF THE CWA. IN OUR AREA PRECIP
WILL BE ALL SNOW. THE WETTEST SNOW WILL BE IN THE FAR SE WHERE 850
TEMPS RISE -2C. ENOUGH TO LOWER RATIOS BUT STILL PLENTY OF QPF FOR
WARNING AMOUNTS. MOIST LOW LEVEL INFLOW OFF OF ATLANTIC SO THAT SE
CWA WILL HAVE QPF OF HALF TO ONE INCH. SHARP GRADIENT ACROSS THE
CWA SO THE FAR WEST WILL HAVE AROUND A TENTH OF AN INCH LIQUID AND
ONLY 1 TO 2 INCHES OF SNOW.
ON THE BACK SIDE TONIGHT QUESTIONS ON HOW STRONG THE WRAPAROUND
WILL BE AND WHERE. THE BIGGEST DUMPER OF SNOW WAS THE EURO IN THAT
RESPECT BUT IT HAS BACKED OFF SOME. BOTH IN QUANTITY AND DURATION.
EITHER WAY WITH THESE STORMS SNOW AMOUNTS WILL VARY WIDELY.
&&
.SHORT TERM /FRIDAY THROUGH SATURDAY NIGHT/...
4 AM UPDATE...
FRIDAY IN BETWEEN SYSTEMS WITH THE NOREASTER PULLING OUT AND A
CLIPPER COMING IN BEHIND IT WITH THE COLD AIR. FIRST LOW GETS
ABSORBED BY THE BOMB OVER SE CANADA. LIGHT SNOW MOSTLY FOR UPSTATE
NY. A SECOND LOW WILL PASS TO THE SOUTH AND BOMB OFF THE MID
ATLANTIC COAST SAT MORNING. THIS WILL SPREAD LIGHT SNOW INTO PA
BUT THE MAIN EVENT WILL BE EAST OF THE CWA.
WITH THE FIRST LOW FRIDAY MORNING LOW LEVEL WINDS SHIFT TO THE NW.
WITH THE MULTIPLE SHORT WAVES AND THE FALLING UL HEIGHTS LAKE
ENHANCEMENT LIKELY WITH SOME LIGHT ACCUMULATIONS. LL FLOW SHIFTS
TO THE W FRI AFTN SO THE SNOW SHIFTS TO MOSTLY ONEIDA. COLDER AIR
COMES IN SAT AND SAT NGT WHILE FLOW GOES BACK TO NW. AGAIN LIGHT
AMOUNTS EXPECTED. DECENT DENDRITE ZONE OF 3 TO 4 KT FEET IN THE
MOIST LAYER WHICH EXTENDS TO 8K FT. COLD AIR ONLY -12C WHICH IS
MARGINAL WITH THE COLD LAKE SFC TEMPS. LAKE EFFECT BUT WEAK AND
MULTIBANDS.
&&
.LONG TERM /SUNDAY THROUGH WEDNESDAY/...
3 AM UPDATE...COLD NORTHWEST FLOW SUNDAY MORNING MAY BRING
SCATTERED SNOW SHOWERS AND FLURRIES SOUTHEAST OF LAKE ONTARIO
FOLLOWED BY PARTLY TO MOSTLY SUNNY CONDITIONS BY AFTERNOON AS SFC
HIGH PRES BUILDS IN. HIGH PRES SUN NGT WITH GOOD RADIATIONAL
COOLING AND FRESH SNOW COVER...WILL LIKELY RESULT IN MINS WELL
BLO ZERO. THIS HIGH MOVS TO THE E CST BY MONDAY EVNG AS A CLIPPER
TYPE SYSTEM HEADS INTO THE ERN GTLAKES. THIS WILL BRING MORE PCPN
TO THE RGN MON NGT INTO TUE....SNOW TRANSITIONING TO A RA/SN MIX
OR PLAIN RAIN ON TUE. WEDNESDAY LOOKS DRY AND MILDER WITH SFC
HIGH PRES OVER THE MID ATLANTIC PROVING A SOUTHWEST MODERATING
FLOW.
&&
.AVIATION /14Z THURSDAY THROUGH MONDAY/...
SFC LOW OVER THE MID ATLANTIC WILL TRACK NORTHEAST INTO COASTAL
NEW ENGLAND BY THIS EVENING. IFR CONDITIONS IN LIGHT SNOW WILL
OVERSPREAD THE TERMINALS BEGINNING AROUND 12Z AT KAVP, 13Z-16Z AT
KBGM/KELM/KITH AND 18Z-20Z AT KRME/KSYR. AT KAVP, AFTER 16Z MODERATE
SNOW WITH CONDITIONS BELOW ALT MINS WILL PERSIST ALL DAY. ACROSS
THE REST OF THE SOUTHERN TERMINALS CONDITIONS WILL DETERIORATE
BELOW ALT MINS DURING THE EARLY AFTERNOON WITH THE MOST RESTRICTIVE
CONDITIONS EXPECTED AT KBGM. THIS EVENING, CONDITIONS AT KRME/KSYR
MAY FALL BELOW ALT MINS. OVERNIGHT CONDITIONS WILL GRADUALLY
IMPROVE BETWEEN 03Z-09Z TO MVFR AND SNOW SHOWERS.
E/SE WINDS AROUND 8-12 KNOTS BECOMING N/NE THIS AFTERNOON THEN
NORTHWEST THIS EVENING.
OUTLOOK...
FRI...MVFR SYR/RME...VFR ELSEWHERE.
FRI NGT...MVFR/IFR FROM -SN AS ANOTHER SYSTEM PASSES.
SAT/SUN...RESTRICTIONS IN LAKE EFFECT -SHSN CENTRAL NY TERMINALS.
SUN NGT/MON...VFR.
&&
.BGM WATCHES/WARNINGS/ADVISORIES...
PA...WINTER STORM WARNING UNTIL 10 AM EST FRIDAY FOR PAZ039-040-043-
044-047-048-072.
WINTER WEATHER ADVISORY UNTIL 10 AM EST FRIDAY FOR PAZ038.
NY...WINTER STORM WARNING UNTIL 10 AM EST FRIDAY FOR NYZ045-046-056-
057-062.
WINTER WEATHER ADVISORY UNTIL 10 AM EST FRIDAY FOR NYZ009-017-
018-024-025-036-037-044-055.
&&
$$
SYNOPSIS...TAC
NEAR TERM...TAC
SHORT TERM...TAC
LONG TERM...RRM
AVIATION...RRM
AREA FORECAST DISCUSSION
NWS RALEIGH NC
841 PM EST FRI FEB 14 2014
.SYNOPSIS...AN UPPER LEVEL DISTURBANCE AND ATTENDANT SURFACE LOW
PRESSURE SYSTEM CROSSES THE REGION OVERNIGHT THROUGH SATURDAY. HIGH
PRESSURE BUILDS IN BEHIND THE SYSTEM FOR SUNDAY.
&&
.NEAR TERM /THROUGH SATURDAY/...
AS OF 840 PM FRIDAY...
THE LATEST SURFACE ANALYSIS SHOWED A SURFACE LOW OVER KENTUCKY
MOVING EAST...WITH COOLING CLOUD TOPS MOVING OVER THE APPALACHIANS
ALTHOUGH THE HIGHER RADAR REFLECTIVITY WAS FARTHER WEST...BASICALLY
IN THE AXIS OF HIGHER PRECIPITABLE WATER VALUES ON THE LATEST SPC
MESOANALYSIS PAGE THAT EXTENDED ACROSS EASTERN KENTUCKY AND
TENNESSEE INTO ALABAMA AND NORTHWEST GEORGIA. THE LATEST KGSO
SOUNDING AT 00Z WAS VERY DRY...ALTHOUGH SURFACE DEW POINTS EVEN IN
THE NORTHWEST PIEDMONT...IN THE TEENS IN SOME PLACES VERY EARLY THIS
EVENING...HAD RISEN INTO THE UPPER 20S SUCH THAT DEW POINTS IN
CENTRAL NORTH CAROLINA RANGED FROM THE UPPER 20S TO THE MID 30S. IN
A FEW LOCATIONS...ESPECIALLY OVER PARTS OF THE SANDHILLS AND THE
COASTAL PLAIN WHERE CLOUDS WERE SLOWER MOVING IN...TEMPERATURES FELL
QUICKLY INTO THE UPPER 30S BUT THESE VALUES SHOULD STABILIZE GIVEN
THE DECENT SURFACE MOISTURE AND THE CLOUDS MOVING IN.
GOOD LIFT IS FORECAST BY THE GUIDANCE LATE TONIGHT WITH 850MB THETA-
E VALUES INCREASING AS THE STRONG MID-LEVEL TROUGH APPROACHES FROM
THE WEST. GOOD DIVERGENCE IS NOTED ON WATER VAPOR IMAGERY AND GOOD
DIVERGENCE IS ALSO FORECAST OVERNIGHT BY THE RAP. THE PRECIPITABLE
WATER AXIS IS FORECAST BY THE RAP TO MOVE INTO CENTRAL NORTH
CAROLINA BY 09Z...COINCIDENT WITH THE LATEST HRRR WHICH SHOWS THE
LEADING EDGE OF PRECIPITATION DEVELOPING A LITTLE FASTER OVER THE
SANDHILLS AND THE PIEDMONT BETWEEN 08Z AND 10Z NEAR WHERE THE RAP
FORECAST ABOUT 100J/KG OF MUCAPE IN THE LAYER BETWEEN 1000MB AND
700MB. THIS PRECIPITATION COULD SPREAD NORTHEAST TOWARD KRWI AND
KIXA PRIOR TO SUNRISE...SO HAVE SPED UP THE TIMING OF THE CHANCES
FOR PRECIPITATION AFTER MIDNIGHT. FOR THE OVERNIGHT HOURS...THE WET-
BULB ZERO TEMPERATURES RISE TO FREEZING OR ABOVE IN CENTRAL NORTH
CAROLINA BY 04Z...AND PARTIAL THICKNESSES ARE INDETERMINATE. SO...
REVIEWING THE BUFR AND RAP SOUNDINGS FOR THE ABOVE-FREEZING LAYER
DEPTH...THROUGH 12Z ALL OF THAT GUIDANCE IS SUFFICIENTLY DEEP WITH
THAT LAYER...AT LEAST TO NEAR 2000FT...TO KEEP THE TYPE LIQUID. MADE
SOME ADJUSTMENTS TO LOWS BASED UPON CURRENT TRENDS...A LITTLE COOLER
WHERE THE TEMPERATURES HAD FALLEN FASTER...AND A DEGREE OR TWO RISE
IN THE TRIAD DUE TO THE QUICKER ONSET OF CLOUDS. WILL CONTINUE THE
POTENTIAL FOR PATCHY FOG IN THE FORECAST BUT DELAYED THE TIMING TO
ONLY BE COINCIDENT WITH ANY CHANCES FOR RAIN.
SATURDAY...THE CLIPPER SURFACE WAVE WILL DEEPEN AS IT MOVES QUICKLY
ENE THROUGH CENTRAL AND EASTERN NC...BEFORE BOMBING AS IT TURNS NE
UP THE MIDDLE ATLANTIC COAST...BENEATH THE STRONGLY DYNAMIC AND
INCREASINGLY NEGATIVELY-TILTED TROUGH ALOFT. IN A SIMILAR SYNOPTIC
PATTERN AND RADAR PRESENTATION AS THE MID-UPPER LOW ON THU...THOUGH
ON A SLIGHTLY MORE SOUTHERN TRACK...A DEFORMATION BAND WILL DEVELOP
ON THE WEST SIDE OF THE RAPIDLY DEEPENING LOW...AND SUBSEQUENTLY
PIVOT EASTWARD THROUGH CENTRAL NC THROUGH MID AFTERNOON. BASED ON
THE HIGH BIAS DISPLAYED WITH PRECIPITATION AMOUNTS BY THE NWP
GUIDANCE FOR THE EVENT FROM THU...WILL FOLLOW THE MORE SUBDUED
CONSENSUS OF THE 12Z ECMWF/NAM OF AROUND ONE QUARTER INCH STORM
TOTAL RAIN. P-TYPE SHOULD INDEED BE JUST THAT - RAIN - OWING TO A
MILD AND RELATIVELY DEEP BOUNDARY LAYER THAT SHOULD COMPLETELY MELT
SNOWFLAKES GENERATED IN...AND FALLING FROM...A COLD/BELOW FREEZING
AND STEEP LAPSE RATE-BEARING LAYER ALOFT. THERE IS STILL A NON-ZERO
CHANCE OF SOME WET SNOWFLAKES ON THE VERY BACK SIDE OF THE
PRECIPITATION OVER THE NORTHERN PIEDMONT...MAINLY TOWARD THE TRIAD
AND KTDF...AROUND 15Z AS THE NAM BUFR AND RAP SOUNDINGS DIMINISH THE
ABOVE FREEZING LAYER BELOW 1000FT. THIS MAY BE OVERDONE...THOUGH...
GIVEN EXPECTED SURFACE TEMPERATURES...AND BY THEN IT IS ANTICIPATED
THE HIGHER-RATE PRECIPITATION WILL BE SHIFTING OFF TO THE EAST.
NEVERTHELESS...IF THE PACE OF PRECIPITATION IS SLOWER TO SHIFT EAST
THAN ANTICIPATED...THIS MAY HAVE TO BE REINTRODUCED TO THE FORECAST
BUT IMPACT...IF IT OCCURS...SHOULD BE QUITE SMALL OWING TO THE
SURFACE TEMPERATURES.
THE BIGGER STORY WILL BE VERY STRONG NW WINDS THAT WILL DEVELOP IN
THE TIGHT PRESSURE GRADIENT BEHIND THE DEPARTING LOW AND INCOMING
UPSTREAM HIGH PRESSURE. BUFR SOUNDINGS INDICATE MIXED LAYER WINDS OF
25-30 KTS...WITH WINDS AT THE TOP OF THE MIXED IN THE MID-UPPER 30S
KTS. THIS MIXING SHOULD SUPPORT SUSTAINED WINDS BETWEEN 15-25
KTS...WITH FREQUENT GUSTS OF 25-30 KTS...DEVELOPING AS THE CLEARING
SPREADS EAST AND THE MIXED LAYER DEEPENS.
&&
.SHORT TERM /SATURDAY NIGHT THROUGH MONDAY NIGHT/...
AS OF 300 PM FRIDAY...
AS LOW PRESSURE EXITS TO THE NORTHEAST SKIES WILL CLEAR OUT FOR MOST
OF SATURDAY NIGHT BEFORE CLOUDS BEGIN TO MOVE IN AGAIN EARLY SUNDAY
MORNING AS A MUCH DRIER...WEAKER CLIPPER SYSTEM APPROACHES FROM THE
NORTHWEST. IN ADDITIONS THE SURFACE FLOW WILL BECOME VERY WEEK AND
RADIATIONAL COOLING WILL ENSUE FOR MOST OF THE NIGHT...HELPING
TEMPERATURES DROP INTO THE MID TO UPPER 20S FOR LOWS SATURDAY NIGHT.
ON SUNDAY THE DRY CLIPPER SYSTEM DROPS THROUGH THE WEAKENING UPPER
LEVEL TROUGH. MOST OF THE LIMITED MOISTURE WITH THIS SYSTEM IS LEFT
ON THE WEST SIDE OF THE APPALACHIANS AND THE SYSTEM DRIES OUT PRETTY
QUICKLY. WILL LEAVE THE FORECAST DRY WITH SOME
CLOUDINESS...ESPECIALLY IN THE NORTH...THAT WILL HELP TO KEEP MAX
TEMPS DOWN ON SUNDAY. EXPECT MID 40S NW TO LOWER 50S ACROSS THE
SOUTH WHERE CLOUD COVER WILL BE LIMITED. SURFACE HIGH PRESSURE WILL
BUILD TO THE NORTHWEST...KEEPING NORTHERLY FLOW OVER CENTRAL NC
THROUGH SUNDAY NIGHT. THIS WEAK COLD AIR ADVECTION AND MOSTLY CLEAR
SKIES WILL ONCE AGAIN BRING LOWS SUNDAY NIGHT DOWN INTO THE MID 20S
TO LOW 30S.
ON MONDAY THE HIGH SHIFTS EASTWARD ACROSS THE MID ATLANTIC STATES
AND WILL TRY TO SET UP A BRIEF HYBRID/IN SITU CAD EVENT...DEPENDING
ON WHAT MODEL YOU BELIEVE. WHILE THE WEDGE FRONT WONT REALLY HAVE A
CHANCE TO GET LOCKED IN...IT WILL BE ENOUGH TO MAKE SKIES OVERCAST
BY MONDAY AFTERNOON WITH SOME DRIZZLE POSSIBLE...MAINLY ACROSS THE
NW PIEDMONT. HIGHS UPPER 40S NW TO MID 50S SE. BY MONDAY NIGHT THE
HIGH MOVES OFFSHORE AND WE BEGIN TO ENTER A WARM AIR ADVECTION
REGIME BETWEEN THE HIGH OFFSHORE AND AN APPROACHING FRONTAL SYSTEM
WEST OF THE MOUNTAINS. LOWS WILL MODERATE TO THE MID 30S TO UPPER
40S MONDAY NIGHT. WE WILL STAY DRY BUT MOISTURE WILL STEADILY
INCREASE INTO TUESDAY.
&&
.LONG TERM /TUESDAY THROUGH FRIDAY/...
AS OF 300 PM FRIDAY...
CONFIDENCE DECREASES IN THE FORECAST BY TUESDAY AS A FRONTAL SYSTEM
APPROACHES FROM THE WEST. WHILE THERE IS HIGH CONFIDENCE THAT A
FRONT WILL CROSS CENTRAL NC SOMETIME ON TUESDAY...DETAILS REGARDING
THE POSITION AND STRENGTH OF THE PARENT LOW AND AMOUNT OF QPF ARE
ALL MURKY AT THIS TIME. WE DO KNOW HOWEVER THAT WITH TEMPERATURES
EXPECTED TO BE IN THE 60S THAT THIS WILL BE AN ALL LIQUID EVENT.
MODEL SOUNDINGS SHOWN IN BUFKIT LEAD TO FAIRLY HIGH CONFIDENCE THAT
THERE WONT BE ANY INSTABILITY AVAILABLE ON TUESDAY FOR THUNDER. THE
FRONT WILL STALL OUT SOMEWHERE SOUTH OF THE AREA ON TUESDAY NIGHT
WITH LOWS GENERALLY IN THE LOW TO MID 40S.
ON WEDNESDAY MORNING THE FRONT WILL RETREAT BACK TO THE NORTH AS A
WARM FRONT AND CROSS THE AREA ONCE AGAIN...WITH PRECIPIATION
POSSIBLE INTO WEDNESDAY AFTERNOON. SOUNDINGS INDICATE THEIR MAY BE
WEAK SURFACE BASED CAPE OF LESS THAN 500 J/KG AVAILABLE OF THE VERY
TALL AND SKINNY VARIETY WITH A DECENT CAP AT 850MB THAT IT WOULD
HAVE TO BUST THROUGH...MAKING CONFIDENCE FOR THUNDER SLIGHTLY BETTER
FOR WEDNESDAY BUT STILL NOT LIKELY. WITH SW FLOW RETURNING HIGHS
WILL SOAR INTO THE MID 60S TO EVEN LOWER 70S POSSIBLE ACROSS THE
SOUTH. WEDNESDAY NIGHT SHOULD BE DRY WITH LOWS MODERATING TO THE
UPPER 40S TO LOW 50S.
FAIRLY STRONG LOW PRESSURE IS EXPECTED TO MOVE OUT OF THE MIDWEST UP
THROUGH THE GREAT LAKES REGION ON THURSDAY. CENTRAL NC WILL REMAIN
NICELY IN THE WARM SECTOR AHEAD OF THIS SYSTEM ON THURSDAY AND THE
ANCHORED BERMUDA HIGH WILL KEEP MOIST SOUTHERLY FLOW OVER THE AREA.
HIGHEST TEMPERATURES OF THE SEASON MAY BE IN ORDER AS HIGHS GO INTO
THE UPPER 60S TO MID 70S NW TO SE. WITH THE EXTRA MOISTURE EXPECT
PARTLY TO MOSTLY CLOUDY SKIES.
ON FRIDAY THE FRONTAL SYSTEM BECOMES MORE EAST TO WEST ORIENTED AS
THE PARENT LOW SPEEDS OFF TO THE NORTHEAST. EXPECT PRECIPITATION TO
OVERSPREAD THE ENTIRE AREA BY FRIDAY AFTERNOON. WITH A LOT OF
MOISTURE AVAILABLE THIS COULD SHAPE UP TO BE A FAIRLY HEAVY RAIN
EVENT BUT IT IS TOO EARLY TO TELL AT THIS TIME. HIGHS FRIDAY
DEPENDENT ON FRONTAL LOCATION.
&&
.AVIATION /00Z SATURDAY THROUGH TUESDAY/...
AS OF 635 PM FRIDAY...
VFR CONDITIONS EXPECTED THROUGH 06Z... BECOMING MVFR AND IFR CIGS
BETWEEN 07Z-10Z. IFR CIGS AND MVFR VSBYS EXPECTED WITH PERIODS OF
LIGHT RAIN AND FOG BETWEEN 09Z AND 15Z SAT. VFR CONDITIONS ARE
EXPECTED TO RAPIDLY RETURN BETWEEN 15Z WEST AND 18Z-21Z EAST AS THE
SYSTEM DEPARTS SATURDAY. HOWEVER... WINDS WILL SHIFT FROM SW TO NW
AND BECOME VERY STRONG AND GUSTY LATE SATURDAY MORNING AND SATURDAY
AFTERNOON. SUSTAINED WINDS OF 15 TO 20KT WILL OCCASIONALLY GUST TO
25-35KT SAT AFTERNOON.
WINDS WILL DIMINISH SAT NIGHT. VFR CIGS AND VSBYS EXPECTED SAT NIGHT
THROUGH MONDAY.
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...DJF
NEAR TERM...MWS/DJF
SHORT TERM...ELLIS
LONG TERM...ELLIS
AVIATION...PWB/MWS
AREA FORECAST DISCUSSION
NWS GRAND FORKS ND
941 PM CST FRI FEB 14 2014
.UPDATE...
ISSUED AT 941 PM CST FRI FEB 14 2014
RADAR RETURNS OVER EASTERN MT HAVE BEEN SLOW TO ENTER THE WESTERN
PART OF ND AND HAVE SHOWN A BIT OF A WEAKENING TREND. THE 00Z NAM
IS QUITE A BIT LESS IMPRESSIVE WITH THE SNOW ENTERING OUR
SOUTHEASTERN CWA THAN PREVIOUS RUNS. THE 02Z RAP HAS THE PRECIP
DISSIPATING BEFORE IT EVEN ENTERS EASTERN ND. WANT TO GET A LOOK
AT THE 00Z GFS AND SEE THE SNOW ENTERING THE WESTERN PART OF THE
STATE BEFORE MAKING MORE RADICAL CHANGES TO POPS. FOR NOW...CUT
THEM QUITE A BIT FOR TONIGHT...KEEPING ONLY A SMALL SLIVER OUT IN
THE WEST BEFORE 12Z. ALSO MADE SOME MINOR ADJUSTEMENTS TO POPS FOR
TOMORROW BUT KEPT THE SOUTH AND WEST IN THE LIKELY CATEGORY FOR
NOW.
TEMP WISE...CLOUDS HAVE KEPT THE NORTHEAST A BIT WARMER THAN
EXPECTED WHILE THE SOUTHEAST HAS ALREADY DROPPED BELOW ZERO. THINK
THAT THE WESTERN COUNTIES SHOULD START RISING IN A FEW HOURS AS
SOUTHERLY WINDS AND CLOUDS MOVE INTO THE REGION. LOWERED LOWS A
BIT IN THE SOUTHERN COUNTIES WHERE BWP HAS ALREADY DROPPED TO
ZERO.
UPDATE ISSUED AT 627 PM CST FRI FEB 14 2014
MADE A FEW MINOR TWEAKS TO MATCH CURRENT CLOUD COVER...BUT NO
MAJOR CHANGES FOR THE EARLY EVENING UPDATE. CONTINUE TO THINK WE
SHOULD SEE A SHARP DROP OVER THE EASTERN COUNTIES AFTER SUNSET AND
THEN RISING TEMPS THROUGHOUT THE AREA FOR THE REST OF THE NIGHT.
&&
.SHORT TERM...(THIS EVENING THROUGH SATURDAY NIGHT)
ISSUED AT 302 PM CST FRI FEB 14 2014
THE MAIN CHALLENGE WILL BE SNOW POTENTIAL TONIGHT INTO SATURDAY
MORNING. MODELS ARE IN DECENT AGREEMENT...WITH ONLY MINOR
DIFFERENCES WITH QPF AND LOCATION. A COUPLE UPPER WAVES WILL
PROPAGATE THROUGH THE REGION LATER TONIGHT INTO SATURDAY. THE
STRONGEST FORCING FROM THESE FEATURES WILL MAINLY AFFECT THE SW FA
AND THE NE FA. MODELS KEEP THE FORCING FROM THESE FEATURES
SEPARATE UNTIL EAST OF THE REGION. THUS...EXPECT AROUND AN INCH OF
SNOWFALL ACROSS THESE AREAS (POSSIBLY A BIT HIGHER FOR NORTHERN
LAKE OF THE WOODS COUNTY).
TEMPERATURES TONIGHT WILL LIKELY FALL UNTIL CLOUDS ARRIVE...THEN
STEADY OR SLOWLY RISE. USED THE CONSSHORT GUIDANCE FOR HOURLY
VALUES.
HIGH PRESSURE MOVES THROUGH THE REGION SATURDAY NIGHT...THUS
LOWERED MIN TEMPS A FEW DEGREES.
.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 302 PM CST FRI FEB 14 2014
SUNDAY-MONDAY...UPPER FLOW WILL BECOME ZONAL AHEAD OF THE NEXT
UPPER WAVE. MODELS ALL INDICATE A PERIOD OF 850MB WARM AIR
ADVECTION SNOW THAT WILL MOVE THROUGH THE AREA SUNDAY
AFTERNOON/NIGHT ASSOCIATED WITH THE UPPER WAVE. THERE IS STILL
SOME DISAGREEMENT WITH EXACTLY HOW/WHEN THIS EVENT WILL
UNFOLD...AND EXACTLY WHERE THE HEAVIEST SNOWFALL WILL BE LOCATED.
AT ANY RATE...1-3 INCHES MOST AREAS...POSSIBLY SLIGHTLY MORE ACROSS
THE SOUTHEAST FA. AHEAD OF THE SNOW...SOUTHERLY WINDS WILL BE BREEZY
(SUNDAY AFTERNOON). MUCH LIKE PAST SOUTHERLY WIND
EVENTS...ANTICIPATE AT LEAST PATCHY BLOWING SNOW ACROSS THE
NORTHERN RED RIVER VALLEY (AND INSERTED THIS INTO THE FORECAST).
SYNOPTIC PATTERN IS SUCH THAT LOW LEVEL WESTERLY FLOW...AND A
WARMER AIRMASS...SHOULD LEAD TO MAX TEMPS NEAR FREEZING ON MONDAY.
MONDAY NIGHT-FRIDAY...LONG TERM WILL SEE A SHIFT FROM A ZONAL
PATTERN EARLY IN THE PERIOD TO LONG WAVE TROUGHING OVER ROCKIES BY
NEXT WEEKEND. WILL SEE A SERIES OF SHORT WAVE TROUGH/RIDGES MOVE
THROUGH IN THE MID WEEK...WITH CHANCES OF SNOW AROUND DAY 6/7.
WITH THE ZONAL PATTERN AND UPPER WAVES MOVING ACROSS SRN
CANADA...SEEING A LOT OF LOW POPS FOR THE SECOND HALF OF THE
PERIOD. BEST CHANCE...HOWEVER...APPEARS TO BE WED NIGHT INTO THU
AS A DEEPER WAVE MOVES ACROSS THE NORTHERN TIER. ECMWF SHOWS A LOW
MOVING OUT OF WYOMING WED AND INVERTED TROUGH LIFTING INTO THE
VALLEY WED NIGHT...HOWEVER PRECIP MAY BE MOSTLY ACROSS THE NORTH
OR SOUTHERN MANITOBA. TEMPS WILL BE IN THE LOW 30S FOR MUCH OF THE
FIRST HALF OF THE WEEK.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z SATURDAY EVENING)
ISSUED AT 627 PM CST FRI FEB 14 2014
VFR CONDITIONS WILL CONTINUE FOR MUCH OF THE PERIOD AS HIGH AND
MID LEVEL CLOUDS INCREASE FROM THE NORTH AND WEST. LIGHT WINDS
SHOULD BEGIN TO INCREASE OUT OF THE SOUTH BUT SHOULD STAY BELOW 12
KTS. SOME SNOW WILL BEGIN TO MOVE INTO THE SOUTHWESTERN PORTIONS
OF THE FORECAST AREA AND MAY CLIP THE KFAR AREA...BUT THINK THAT
BEST SNOW BAND WITH LOWEST VIS WILL STAY AWAY FROM THE TAF SITES
AT THIS POINT. A FRONTAL BOUNDARY DROPPING INTO THE AREA WILL
SHIFT WINDS TO THE NORTH AND COULD BRING SOME MVFR CIGS INTO THE
AREA BY AFTERNOON.
&&
.FGF WATCHES/WARNINGS/ADVISORIES...
ND...NONE.
MN...NONE.
&&
$$
UPDATE...JR
SHORT TERM...TG
LONG TERM...TG/SPEICHER
AVIATION...JR
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
406 PM EST THU FEB 13 2014
.SYNOPSIS...
A RAPIDLY INTENSIFYING WINTER STORM JUST EAST OF WALLOPS ISLAND
EARLY THIS AFTERNOON...WILL MOVE UP THROUGH SOUTHERN NEW ENGLAND
TONIGHT. A COLD FRONT WILL SWEEP THROUGH THE REGION ON
FRIDAY...WITH ADDITIONAL WEAK DISTURBANCES BRINGING A CHANCE OF
LIGHT SNOW SHOWERS OVER THE FIRST PART OF A WEEKEND. HIGH PRESSURE
WILL BUILD ACROSS EASTERN CANADA SUNDAY NIGHT...BRINGING ANOTHER
COLD NIGHT TO THE KEYSTONE STATE. TEMPERATURES WILL SLOWLY
MODERATE NEXT WEEK...AS A SERIES OF STORM SYSTEMS PULL WARMER AIR
INTO THE AREA.
&&
.NEAR TERM /UNTIL 6 AM FRIDAY MORNING/...
MAIN PLAYER IN THE NEAR TERM CONTINUES TO BE A BAND OF
SNOW...APPROX 20 MILES WIDE...THAT HAS BEEN BACKING WESTWARD
THROUGH SERN PA. THE BAND CURRENTLY EXTENDS FROM BEDFORD UP
THROUGH STATE COLLEGE TO JUST SOUTH OF WILLIAMSPORT...AND HAS
BEEN MOVING SLOWLY NW...AT 10-15 MPH. WE HAVE BEEN RECEIVING
REPORTS OF SNOW RATES OF 1-2 INCHES PER HOUR UNDER THIS BAND OF
VERY HEAVY SNOW.
OVER FAR SERN PA...ENOUGH WARM AIR HAS MOVED IN TO MAKE FOR A
WINTRY MIX OF SNOW/SLEET/FREEZING RAIN AND EVEN SOME RAIN WHERE
SURFACE TEMPS HAVE CREPT ABOVE FREEZING. SNOWFALL AMOUNTS DOWN
THERE IN THE RANGE OF 10-15" ARE COMMON. ADDITIONAL SNOW AMOUNTS
THROUGH LATE AFTERNOON IN THIS AREA OF A WINTRY MIX ARE LIKELY TO
BE SMALL TO NON EXISTENT WITH THE SLEET/FREEZING RAIN OR RAIN
TAMPING THINGS DOWN.
BIGGEST TWEAK TO NEAR TERM WAS INCLUDING BLAIR COUNTY IN THE
WINTER STORM WARNING AS THE BAND HAS BEEN BASICALLY PIVOTING OVER
OR VERY NEAR SOUTHERN BLAIR AND WE HAVE ALREADY RECEIVED SNOW
REPORTS IN EXCESS OF 8 INCHES FURTHER EAST WHERE THE BAND HAS BEEN
SLOWLY MOVING THROUGH.
BUT OVERALL SCENARIO IS PLAYING OUT PRETTY CLOSE TO EXPECTED.
EXPECT THE SNOW TO CONTINUE INTO THE AFTERNOON OVER CENTRAL
AREAS...WITH THE WINTRY MIX OR EVEN A LULL IN PRECIP DOMINATING
THE AREA SOUTH AND EAST OF A HARRISBURG TO GETTYSBURG LINE.
RUC CONTINUES THE LOW LEVEL FRONTOGENETIC FORCING OVER CENTRAL
AREAS INTO THE LATE AFTERNOON...WHICH LOOKS REASONABLE AS THE
UPPER LOW AND DRY SLOW PIVOT UP FROM THE CAROLINAS.
THE FORECAST PROBLEM FOR THE REMAINDER OF THE NEAR TERM BEYOND OUR
CURRENT SNOW BAND...WILL BE THE POTENTIAL FOR MORE DEFORMATION
ZONE SNOW TO FORM AND SWING THROUGH CENTRAL AND SOUTHEASTERN PA AS
THE UPPER LOW FINALLY CLEARS THE AREA THIS EVENING. THE HRRR SHOWS
THIS SCENARIO DEVELOPING BETWEEN ROUGHLY 5 AND 9 PM. EXACT
PLACEMENT OF FEATURES IN THE MESO MODELS IS OFTEN SUSPECT...BUT
THE MODE OF PRECIP IS OFTEN PRETTY WELL REPRESENTED. HAVE TO BE
AWARE OF THE POTENTIAL FOR ADDITIONAL SNOWFALL ACCUMS OF 1-3
INCHES OR SO UNDER THIS POTENTIAL DEFORMATION ZONE.
ACTIVITY SHOULD FINALLY WIND DOWN REGION-WIDE BETWEEN 00Z AND
06Z...LEAVING LITTLE MORE THAN SCATTERED SNOW SHOWERS BY MIDNIGHT.
LOWS SHOULD RANGE FROM THE MID TEENS TO MID 20S FROM NW TO SE.
&&
.SHORT TERM /6 AM FRIDAY MORNING THROUGH 6 PM FRIDAY/...
FRIDAY WILL BE BLUSTERY BUT NOT TERRIBLY COLD IN THE WAKE OF OUR
STORM. A WEAK CLIPPER TYPE LOW GETS ABSORBED INTO OUR LARGER STORM
THAT BY MID DAY WILL BE MOVING UP INTO THE MARITIMES. PRECIP WITH
THIS CLIPPER LOW/WEAK COLD FRONT WILL BE LIGHT AND MAINLY
CONFINED TO WESTERN PA IN THE FORM OF SOME SNOW SHOWERS.
&&
.LONG TERM /FRIDAY NIGHT THROUGH THURSDAY/...
A SERIES OF WEAK SYSTEMS WILL DROP SE ON SAT...BRINGING SCATTERED
SNOW SHOWERS THROUGHOUT THE CENTRAL VALLEYS...WITH PERIODS OF SNOW
SHOWERS ACROSS THE ALLEGHENY PLATEAU. A SEVERAL HOUR PERIOD OF
STEADY LIGHT OT MDT SNOW IS POSSIBLE ACROSS THE SOUTHERN TIER
COUNTIES OF THE STATE AS A POTENT UPPER TROUGH AND SFC LOW SLIDES
EAST ACROSS WVA AND NRN VA. WILL HAVE TO WATCH THIS FEATURE
CLOSELY FOR POSSIBLY OF JUST ENOUGH SNOW /ACROSS THE LAURELS AND
SOUTHERN TIER OF PENN/ FOR A WINTER WEATHER ADVISORY LATE FRIDAY
NIGHT INTO SATURDAY /ESPECIALLY ACROSS THE LOWER SUSQ VALLEY AS
THE SFC LOW QUICKLY STRENGTHENS AS IT NEARS THE EAST COAST. FOR
NOW...DID UP POPS AND AMTS SOME.
FOR SUNDAY...SYSTEM DROPPING SOUTH OF PA MAY BRING A FEW
SNOW SHOWERS TO THE FAR WEST EARLY. MAYBE A LITTLE LIGHT
SNOW FURTHER EAST DURING THE DAY.
IT WILL BE A COLD NIGHT SUNDAY NIGHT...GIVEN THAT COLD HIGH
PRESSURE BUILDS SOUTHWARD FROM EASTERN CANADA...MUCH LIKE
WED AM.
A CHC OF RAIN AND SNOW SHOWERS FOR LATE MONDAY INTO TUE.
SHOULD BE DRY ON WED WITH HIGH PRESSURE BUILDING IN.
RETURN FLOW AROUND THE HIGH AFTER TUESDAY COULD WARM TEMPS
BY A LOT BY LATER NEXT WEEK...BUT SNOW COVER AND ICE ON
LAKES MAY TAPER THINGS. PATTERN SUPPORTS A WARM UP ACROSS
THE SOUTHERN STATES...BUT COLDER AIR STILL TO THE NORTH. ONE
COULD SEE A 20 TO 30 DEGREE GRADIENT IN TEMPS FROM N PA TO S PA
BY LATE NEXT WEEK.
WENT WITH A DRY FCST FOR THU.
&&
.AVIATION /21Z THURSDAY THROUGH TUESDAY/...
SNOW WILL CONTINUE OVER MOST OF THE AREA THROUGH LATE AFTERNOON
WITH IFR/LIFR DOMINATING. HARRISBURG AREA AND SOUTHWARD WILL BE
RIGHT IN THE PRECIP TRANSITION AREA WHERE A WINTRY MIX OF
SNOW/SLEET AND RAIN WILL ALSO BE POSSIBLE.
WINDS WILL INCREASE TO 10-15 KTS WITH GUSTS APPROACHING 25 KTS IN
THE SUSQ VALLEY DURING THE DAY AS THE LOW DEEPENS.
EXPECT IFR TO SLOWLY IMPROVE LATER THIS EVENING AND OVERNIGHT AS
THE STORM MOVES UP INTO NEW ENGLAND AND WINDS SHIFT TO THE NW.
CONDITIONS WILL DETERIORATE AGAIN TOMORROW AS A CLIPPER SLIDES IN
FROM THE WEST...BRINGING LIGHT SNOW AND RESTRICTIONS BACK TO
MAINLY WESTERN HALF OF CWA.
ANOTHER WEAK STORM WILL SLIDE OFF THROUGH VA FRI NIGHT AND SAT
MORNING...BRINGING REDUCED FLYING CONDITIONS MAINLY FROM ALTOONA
EASTWARD.
OUTLOOK...
SAT-SUN...MVFR TO IFR WITH SCT SHSN WEST. MAINLY VFR CENTRAL AND
EAST.
MON...LOWERING CONDITIONS WITH THE APPROACH OF A COLD FRONT FROM
THE GREAT LAKES.
TUE...NO SIG WX.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
WINTER WEATHER ADVISORY UNTIL 10 PM EST THIS EVENING FOR
PAZ012-017-037-041-042-045-046.
WINTER STORM WARNING UNTIL 10 PM EST THIS EVENING FOR PAZ018-
019-024>028-033>036-049>053-056>059-063>066.
&&
$$
SYNOPSIS...LA CORTE/MARTIN
NEAR TERM...LA CORTE
SHORT TERM...LA CORTE
LONG TERM...LAMBERT/MARTIN
AVIATION...LA CORTE
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
141 PM EST THU FEB 13 2014
.SYNOPSIS...
A RAPIDLY INTENSIFYING WINTER STORM JUST EAST OF WALLOPS ISLAND
EARLY THIS AFTERNOON...WILL MOVE UP THROUGH SOUTHERN NEW ENGLAND
TONIGHT. A COLD FRONT WILL SWEEP THROUGH THE REGION ON
FRIDAY...WITH ADDITIONAL WEAK DISTURBANCES BRINGING A CHANCE OF
LIGHT SNOW SHOWERS OVER THE FIRST PART OF A WEEKEND. HIGH PRESSURE
WILL BUILD ACROSS EASTERN CANADA SUNDAY NIGHT. TEMPERATURES WILL
SLOWLY MODERATE NEXT WEEK...AS A SERIES OF STORM SYSTEMS PULL
WARMER AIR INTO THE AREA.
&&
.NEAR TERM /THROUGH TONIGHT/...
MAIN PLAYER IN THE NEAR TERM CONTINUES TO BE A BAND OF
SNOW...APPROX 20 MILES WIDE...THAT HAS BEEN BACKING WESTWARD
THROUGH SERN PA. THE BAND CURRENTLY EXTENDS FROM BEDFORD UP
THROUGH STATE COLLEGE TO JUST SOUTH OF WILLIAMSPORT...AND HAS
BEEN MOVING SLOWLY NW...AT 10-15 MPH. WE HAVE BEEN RECEIVING
REPORTS OF SNOW RATES OF 1-2 INCHES PER HOUR UNDER THIS BAND OF
VERY HEAVY SNOW.
OVER FAR SERN PA...ENOUGH WARM AIR HAS MOVED IN TO MAKE FOR A
WINTRY MIX OF SNOW/SLEET/FREEZING RAIN AND EVEN SOME RAIN WHERE
SURFACE TEMPS HAVE CREPT ABOVE FREEZING. SNOWFALL AMOUNTS DOWN
THERE IN THE RANGE OF 10-15" ARE COMMON. ADDITIONAL SNOW AMOUNTS
THROUGH LATE AFTERNOON IN THIS AREA OF A WINTRY MIX ARE LIKELY TO
BE SMALL TO NON EXISTENT WITH THE SLEET/FREEZING RAIN OR RAIN
TAMPING THINGS DOWN.
BIGGEST TWEAK TO NEAR TERM WAS INCLUDING BLAIR COUNTY IN THE
WINTER STORM WARNING AS THE BAND HAS BEEN BASICALLY PIVOTING OVER
OR VERY NEAR SOUTHERN BLAIR AND WE HAVE ALREADY RECEIVED SNOW
REPORTS IN EXCESS OF 8 INCHES FURTHER EAST WHERE THE BAND HAS BEEN
SLOWLY MOVING THROUGH.
BUT OVERALL SCENARIO IS PLAYING OUT PRETTY CLOSE TO EXPECTED.
EXPECT THE SNOW TO CONTINUE INTO THE AFTERNOON OVER CENTRAL
AREAS...WITH THE WINTRY MIX OR EVEN A LULL IN PRECIP DOMINATING
THE AREA SOUTH AND EAST OF A HARRISBURG TO GETTYSBURG LINE.
RUC CONTINUES THE LOW LEVEL FRONTOGENETIC FORCING OVER CENTRAL
AREAS INTO THE LATE AFTERNOON...WHICH LOOKS REASONABLE AS THE
UPPER LOW AND DRY SLOW PIVOT UP FROM THE CAROLINAS.
THE FORECAST PROBLEM FOR THE REMAINDER OF THE NEAR TERM BEYOND OUR
CURRENT SNOW BAND...WILL BE THE POTENTIAL FOR MORE DEFORMATION
ZONE SNOW TO FORM AND SWING THROUGH CENTRAL AND SOUTHEASTERN PA AS
THE UPPER LOW FINALLY CLEARS THE AREA THIS EVENING. THE HRRR SHOWS
THIS SCENARIO DEVELOPING BETWEEN ROUGHLY 5 AND 9 PM. EXACT
PLACEMENT OF FEATURES IN THE MESO MODELS IS OFTEN SUSPECT...BUT
THE MODE OF PRECIP IS OFTEN PRETTY WELL REPRESENTED. HAVE TO BE
AWARE OF THE POTENTIAL FOR ADDITIONAL SNOWFALL ACCUMS OF 1-3
INCHES OR SO UNDER THIS POTENTIAL DEFORMATION ZONE.
ACTIVITY SHOULD FINALLY WIND DOWN REGION-WIDE BETWEEN 00Z AND
06Z...LEAVING LITTLE MORE THAN SCATTERED SNOW SHOWERS BY MIDNIGHT.
LOWS SHOULD RANGE FROM THE MID TEENS TO MID 20S FROM NW TO SE.
&&
.SHORT TERM /FRIDAY/...
FRIDAY WILL BE BLUSTERY BUT NOT TERRIBLY COLD IN THE WAKE OF OUR
STORM. A WEAK CLIPPER TYPE LOW GETS ABSORBED INTO OUR LARGER STORM
THAT BY MID DAY WILL BE MOVING UP INTO THE MARITIMES. PRECIP WITH
THIS CLIPPER LOW/WEAK COLD FRONT WILL BE LIGHT AND MAINLY
CONFINED TO WESTERN PA IN THE FORM OF SOME SNOW SHOWERS.
&&
.LONG TERM /FRIDAY NIGHT THROUGH THURSDAY/...
A SERIES OF WEAK SYSTEMS WILL DROP SE ON SAT...BRINGING SCATTERED
SNOW SHOWERS THROUGHOUT THE CENTRAL VALLEYS...WITH PERIODS OF SNOW
SHOWERS ACROSS THE ALLEGHENY PLATEAU. A SEVERAL HOUR PERIOD OF
STEADY LIGHT OT MDT SNOW IS POSSIBLE ACROSS THE SOUTHERN TIER
COUNTIES OF THE STATE AS A POTENT UPPER TROUGH AND 1002-1004 SFC LOW
SLIDES EAST ACROSS WVA AND NRN VA. WILL HAVE TO WATCH THIS FEATURE
CLOSELY FOR POSSIBLY OF JUST ENOUGH SNOW /ACROSS THE LAURELS AND
SOUTHERN TIER OF PENN/ FOR A WINTER WEATHER ADVISORY LATE FRIDAY
NIGHT INTO SATURDAY /ESPECIALLY ACROSS THE LOWER SUSQ VALLEY AS THE
SFC LOW QUICKLY STRENGTHENS AS IT NEARS THE EAST COAST.
FOR SUNDAY...SYSTEM DROPPING SOUTH OF PA MAY BRING A FEW
SNOW SHOWERS TO THE FAR WEST EARLY.
DID LOWER TEMPS SUNDAY NIGHT BY A LOT...GIVEN THAT COLD
HIGH PRESSURE BUILDS SOUTHWARD FROM EASTERN CANADA...MUCH
LIKE THIS AM.
SLOWER WITH THE PRECIPITATION AND WARM UP ON MONDAY.
GFS LOOKS TOO FAST WITH THE FRONT ON TUESDAY STILL...THUS
WEIGHTED FCST TO WPC CHARTS AND EC OUTPUT.
SHOULD BE DRY ON WED.
RETURN FLOW AROUND THE HIGH AFTER TUESDAY COULD WARM TEMPS
BY A LOT BY LATER NEXT WEEK...BUT SNOW COVER AND ICE ON
LAKES MAY TAPER THINGS. PATTERN SUPPORTS A WARM UP ACROSS
THE SOUTHERN STATES...BUT COLDER AIR STILL TO THE NORTH. ONE
COULD SEE A 20 TO 30 DEGREE GRADIENT IN TEMPS FROM N PA TO S PA
BY LATE NEXT WEEK.
&&
.AVIATION /19Z THURSDAY THROUGH TUESDAY/...
SNOW WILL CONTINUE OVER MOST OF THE AREA THROUGH LATE AFTERNOON
WITH IFR/LIFR DOMINATING. HARRISBURG AREA AND SOUTHWARD WILL BE
RIGHT IN THE PRECIP TRANSITION AREA WHERE A WINTRY MIX OF
SNOW/SLEET AND RAIN WILL ALSO BE POSSIBLE.
WINDS WILL INCREASE TO 10-15 KTS WITH GUSTS APPROACHING 25 KTS IN
THE SUSQ VALLEY DURING THE DAY AS THE LOW DEEPENS.
EXPECT IFR TO SLOWLY IMPROVE LATER THIS EVENING AND OVERNIGHT AS
THE STORM MOVES UP INTO NEW ENGLAND AND WINDS SHIFT TO THE NW.
CONDITIONS WILL DETERIORATE AGAIN TOMORROW AS A CLIPPER SLIDES IN
FROM THE WEST...BRINGING LIGHT SNOW AND RESTRICTIONS BACK TO
MAINLY WESTERN HALF OF CWA.
ANOTHER WEAK STORM WILL SLIDE OFF THROUGH VA FRI NIGHT AND SAT
MORNING...BRINGING REDUCED FLYING CONDITIONS MAINLY FROM ALTOONA
EASTWARD.
OUTLOOK...
SAT-SUN...MVFR TO IFR WITH SCT SHSN WEST. MAINLY VFR CENTRAL AND
EAST.
MON...LOWERING CONDITIONS WITH THE APPROACH OF A COLD FRONT FROM
THE GREAT LAKES.
TUE...NO SIG WX.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
WINTER WEATHER ADVISORY UNTIL 10 PM EST THIS EVENING FOR
PAZ012-017>019-024-033-037-041-042-045-046.
WINTER STORM WARNING UNTIL 10 PM EST THIS EVENING FOR
PAZ025>028-034>036-049>053-056>059-063>066.
&&
$$
SYNOPSIS...LA CORTE
NEAR TERM...LA CORTE
SHORT TERM...LA CORTE
LONG TERM...LAMBERT/MARTIN
AVIATION...LA CORTE
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
139 PM EST THU FEB 13 2014
.SYNOPSIS...
A RAPIDLY INTENSIFYING WINTER STORM JUST EAST OF WALLOPS ISLAND
EARLY THIS AFTERNOON...WILL MOVE UP THROUGH SOUTHERN NEW ENGLAND
TONIGHT. A COLD FRONT WILL SWEEP THROUGH THE REGION ON
FRIDAY...WITH ADDITIONAL WEAK DISTURBANCES BRINGING A CHANCE OF
LIGHT SNOW SHOWERS OVER THE FIRST PART OF A WEEKEND. HIGH PRESSURE
WILL BUILD ACROSS EASTERN CANADA SUNDAY NIGHT. TEMPERATURES WILL
SLOWLY MODERATE NEXT WEEK...AS A SERIES OF STORM SYSTEMS PULL
WARMER AIR INTO THE AREA.
&&
.NEAR TERM /THROUGH TONIGHT/...
MAIN PLAYER IN THE NEAR TERM CONTINUES TO BE A BAND OF
SNOW...APPROX 20 MILES WIDE...THAT HAS BEEN BACKING WESTWARD
THROUGH SERN PA. THE BAND CURRENTLY EXTENDS FROM BEDFORD UP
THROUGH STATE COLLEGE TO JUST SOUTH OF WILLIAMSPORT...AND HAS
BEEN MOVING SLOWLY NW...AT 10-15 MPH. WE HAVE BEEN RECEIVING
REPORTS OF SNOW RATES OF 1-2 INCHES PER HOUR UNDER THIS BAND OF
VERY HEAVY SNOW.
OVER FAR SERN PA...ENOUGH WARM AIR HAS MOVED IN TO MAKE FOR A
WINTRY MIX OF SNOW/SLEET/FREEZING RAIN AND EVEN SOME RAIN WHERE
SURFACE TEMPS HAVE CREPT ABOVE FREEZING. SNOWFALL AMOUNTS DOWN
THERE IN THE RANGE OF 10-15" ARE COMMON. ADDITIONAL SNOW AMOUNTS
THROUGH LATE AFTERNOON IN THIS AREA OF A WINTRY MIX ARE LIKELY TO
BE SMALL TO NON EXISTENT WITH THE SLEET/FREEZING RAIN OR RAIN
TAMPING THINGS DOWN.
BIGGEST TWEAK TO NEAR TERM WAS INCLUDING BLAIR COUNTY IN THE
WINTER STORM WARNING AS THE BAND HAS BEEN BASICALLY PIVOTING OVER
OR VERY NEAR SOUTHERN BLAIR AND WE HAVE ALREADY RECEIVED SNOW
REPORTS IN EXCESS OF 8 INCHES FURTHER EAST WHERE THE BAND HAS BEEN
SLOWLY MOVING THROUGH.
BUT OVERALL SCENARIO IS PLAYING OUT PRETTY CLOSE TO EXPECTED.
EXPECT THE SNOW TO CONTINUE INTO THE AFTERNOON OVER CENTRAL
AREAS...WITH THE WINTRY MIX OR EVEN A LULL IN PRECIP DOMINATING
THE AREA SOUTH AND EAST OF A HARRISBURG TO GETTYSBURG LINE.
RUC CONTINUES THE LOW LEVEL FRONTOGENETIC FORCING OVER CENTRAL
AREAS INTO THE LATE AFTERNOON...WHICH LOOKS REASONABLE AS THE
UPPER LOW AND DRY SLOW PIVOT UP FROM THE CAROLINAS.
THE FORECAST PROBLEM FOR THE REMAINDER OF THE NEAR TERM BEYOND OUR
CURRENT SNOW BAND...WILL BE THE POTENTIAL FOR MORE DEFORMATION
ZONE SNOW TO FORM AND SWING THROUGH CENTRAL AND SOUTHEASTERN PA AS
THE UPPER LOW FINALLY CLEARS THE AREA THIS EVENING. THE HRRR SHOWS
THIS SCENARIO DEVELOPING BETWEEN ROUGHLY 5 AND 9 PM. EXACT
PLACEMENT OF FEATURES IN THE MESO MODELS IS OFTEN SUSPECT...BUT
THE MODE OF PRECIP IS OFTEN PRETTY WELL REPRESENTED. HAVE TO BE
AWARE OF THE POTENTIAL FOR ADDITIONAL SNOWFALL ACCUMS OF 1-3
INCHES OR SO UNDER THIS POTENTIAL DEFORMATION ZONE.
ACTIVITY SHOULD FINALLY WIND DOWN REGION-WIDE BETWEEN 00Z AND
06Z...LEAVING LITTLE MORE THAN SCATTERED SNOW SHOWERS BY MIDNIGHT.
LOWS SHOULD RANGE FROM THE MID TEENS TO MID 20S FROM NW TO SE.
&&
.SHORT TERM /FRIDAY/...
FRIDAY WILL BE BLUSTERY BUT NOT TERRIBLY COLD IN THE WAKE OF OUR
STORM. A WEAK CLIPPER TYPE LOW GETS ABSORBED INTO OUR LARGER STORM
THAT BY MID DAY WILL BE MOVING UP INTO THE MARITIMES. PRECIP WITH
THIS CLIPPER LOW/WEAK COLD FRONT WILL BE LIGHT AND MAINLY
CONFINED TO WESTERN PA IN THE FORM OF SOME SNOW SHOWERS.
&&
.LONG TERM /FRIDAY NIGHT THROUGH THURSDAY/...
A SERIES OF WEAK SYSTEMS WILL DROP SE ON SAT...BRINGING SCATTERED
SNOW SHOWERS THROUGHOUT THE CENTRAL VALLEYS...WITH PERIODS OF SNOW
SHOWERS ACROSS THE ALLEGHENY PLATEAU. A SEVERAL HOUR PERIOD OF
STEADY LIGHT OT MDT SNOW IS POSSIBLE ACROSS THE SOUTHERN TIER
COUNTIES OF THE STATE AS A POTENT UPPER TROUGH AND 1002-1004 SFC LOW
SLIDES EAST ACROSS WVA AND NRN VA. WILL HAVE TO WATCH THIS FEATURE
CLOSELY FOR POSSIBLY OF JUST ENOUGH SNOW /ACROSS THE LAURELS AND
SOUTHERN TIER OF PENN/ FOR A WINTER WEATHER ADVISORY LATE FRIDAY
NIGHT INTO SATURDAY /ESPECIALLY ACROSS THE LOWER SUSQ VALLEY AS THE
SFC LOW QUICKLY STRENGTHENS AS IT NEARS THE EAST COAST.
FOR SUNDAY...SYSTEM DROPPING SOUTH OF PA MAY BRING A FEW
SNOW SHOWERS TO THE FAR WEST EARLY.
DID LOWER TEMPS SUNDAY NIGHT BY A LOT...GIVEN THAT COLD
HIGH PRESSURE BUILDS SOUTHWARD FROM EASTERN CANADA...MUCH
LIKE THIS AM.
SLOWER WITH THE PRECIPITATION AND WARM UP ON MONDAY.
GFS LOOKS TOO FAST WITH THE FRONT ON TUESDAY STILL...THUS
WEIGHTED FCST TO WPC CHARTS AND EC OUTPUT.
SHOULD BE DRY ON WED.
RETURN FLOW AROUND THE HIGH AFTER TUESDAY COULD WARM TEMPS
BY A LOT BY LATER NEXT WEEK...BUT SNOW COVER AND ICE ON
LAKES MAY TAPER THINGS. PATTERN SUPPORTS A WARM UP ACROSS
THE SOUTHERN STATES...BUT COLDER AIR STILL TO THE NORTH. ONE
COULD SEE A 20 TO 30 DEGREE GRADIENT IN TEMPS FROM N PA TO S PA
BY LATE NEXT WEEK.
&&
.AVIATION /17Z THURSDAY THROUGH TUESDAY/...
SNOW WILL CONTINUE OVER MOST OF THE AREA THROUGH LATE AFTERNOON
WITH IFR/LIFR DOMINATING. HARRISBURG AREA AND SOUTHWARD WILL BE
RIGHT IN THE PRECIP TRANSITION AREA WHERE A WINTRY MIX OF
SNOW/SLEET AND RAIN WILL ALSO BE POSSIBLE.
WINDS WILL INCREASE TO 10-15 KTS WITH GUSTS APPROACHING 25 KTS IN
THE SUSQ VALLEY DURING THE DAY AS THE LOW DEEPENS.
EXPECT IFR TO SLOWLY IMPROVE LATER THIS EVENING AND OVERNIGHT AS
THE STORM MOVES UP INTO NEW ENGLAND AND WINDS SHIFT TO THE NW.
CONDITIONS WILL DETERIORATE AGAIN TOMORROW AS A CLIPPER SLIDES IN
FROM THE WEST...BRINGING LIGHT SNOW AND RESTRICTIONS BACK TO
MAINLY WESTERN HALF OF CWA.
ANOTHER WEAK STORM WILL SLIDE OFF THROUGH VA FRI NIGHT AND SAT
MORNING...BRINGING REDUCED FLYING CONDITIONS MAINLY FROM ALTOONA
EASTWARD.
OUTLOOK...
SAT-SUN...MVFR TO IFR WITH SCT SHSN WEST. MAINLY VFR CENTRAL AND
EAST.
MON...LOWERING CONDITIONS WITH THE APPROACH OF A COLD FRONT FROM
THE GREAT LAKES.
TUE...NO SIG WX.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
WINTER WEATHER ADVISORY UNTIL 10 PM EST THIS EVENING FOR
PAZ012-017>019-024-025-033-037-041-042-045-046.
WINTER STORM WARNING UNTIL 10 PM EST THIS EVENING FOR
PAZ026>028-034>036-049>053-056>059-063>066.
&&
$$
SYNOPSIS...LA CORTE
NEAR TERM...LA CORTE
SHORT TERM...LA CORTE
LONG TERM...LAMBERT/MARTIN
AVIATION...LA CORTE
AREA FORECAST DISCUSSION
NWS GREENVILLE-SPARTANBURG SC
944 PM EST FRI FEB 14 2014
.SYNOPSIS...
AN UPPER LEVEL SYSTEM WILL QUICKLY CROSS THE REGION TONIGHT...
FOLLOWED BY HIGH PRESSURE SATURDAY. ANOTHER UPPER SYSTEM WILL CROSS
THE AREA EARLY SUNDAY...FOLLOWED BY MORE HIGH PRESSURE IN MONDAY. A
COLD FRONT WILL REACH THE AREA FROM THE WEST ON TUESDAY.
&&
.NEAR TERM /THROUGH SATURDAY/...
930 PM UPDATE...PATCHES OF LIGHT PRECIP SEEN ON RADARS ATTM FROM FAR
ERN KY AND SRN WV DOWN THRU THE GREAT VALLEY AND INTO ERN AL. THESE
ARE ALL AHEAD OF THE UPPER SHORTWAVE. SFC OBS INDICATE RATES OF A
FEW HUNDREDTHS PER HOUR. SPC MESOANALYSIS SUGGESTS THE NE ALABAMA
ACTIVITY...WHICH PER TRENDS WOULD AFFECT OUR CWFA THE MOST...IS
OCCURRING IN AN AREA OF WEAK WARM UPGLIDE AHEAD OF THE BASE OF THE
850MB TROUGH. RUC PROGS SUGGEST THIS FORCING DIVES SEWD ACRS GA AND
INTO THE SC MIDLANDS...BUT THEY STILL SHOW SOME LIGHT QPF CROSSING
THE FA DIRECTLY AHEAD OF THE UPPER WAVE AND REASONABLY CLOSE TO
EARLIER TIMING. TWEAKED POPS DOWNWARD THIS EVENING TO ACCOUNT FOR
THE SPOTTY NATURE OF THE ACTIVITY NOW ENTERING SW NC AND NE GA...BUT
OVERALL POPS LOOK REASONABLE...AND THE PRECIP RATES SUGGESTED BY THE
GOING QPF ARE OK. 00Z NAM SEEMS TO MOVE THE PRECIP OUT FASTER
TOMORROW MORNING. TEMPS AND DEWPOINTS WERE OK BUT DID TOUCH THEM UP
ONCE AGAIN PER SHORT TERM CONSENSUS GUIDANCE. NEW TEMPS ARE SOMEWHAT
WARMER ESPECIALLY EARLY IN THE EVENT IN THE MTNS...WHICH REDUCES THE
STORM TOTAL SNOWFALL IN SOME PLACES DUE TO HIGHER SNOW LEVELS THIS
EVENING. WILL REISSUE WSW PRODUCT SHORTLY BUT WORDING WILL LIKELY BE
VERY CLOSE TO THAT ALREADY USED.
700 PM UPDATE...REVISED POPS...AND TO A LESSER EXTENT QPF...
FOLLOWING THE 18Z NAM/GFS AND 15Z SREF. THE MODELS GENERALLY AGREE
ON A WAVE OF PRECIP PASSING THRU THE PIEDMONT BEFORE DAYBREAK.
ISENTROPIC FORCING DOES LOOK PRETTY LIMITED BUT IT IS HARD TO IGNORE
THE DYNAMIC LIFT AND DEEP COLUMN OF MOISTURE PROGGED TO CROSS WITH
THE SHORTWAVE. ALSO RECALL THAT THE TRACK OF THIS WAVE IS PRETTY
SIMILAR TO THAT THURSDAY MORNING...WHICH THE NAM/GFS CORRECTLY
INDICATED WOULD BRING PRECIP TO THE PIEDMONT IN ITS DEFORMATION
ZONE. THUS FELT CONFIDENT ENOUGH TO GO CATEGORICAL...IF NOT
BRIEFLY...IN A BAND TRAVERSING THE CWFA. QPF STILL LOOKED PRETTY
GOOD BUT MADE CHANGES MAINLY EAST OF THE SNOW AREA. IT CONTINUES TO
LOOK LIKE THE COLDER AIR CAPABLE OF ALLOWING SNOW TO REACH THE
SURFACE EAST OF THE MTNS/FOOTHILLS WILL NOT PUSH IN FAST ENOUGH TO
ALLOW MUCH SNOW ACCUMULATION. SNOW MENTION IS A BIT LESS EXPANSIVE
OVER THE NC PIEDMONT AS A RESULT. IN THE MTNS...ACCUMS ARE PRETTY
SIMILAR WITH THE ONLY TOTALS ABOVE ADVY CRITERIA SHOWN IN THE
HIGHEST ELEVATIONS. TEMP/DEWPT TRENDS FROM EARLIER UPDATE STILL LOOK
TO BE ON TRACK.
ON ANOTHER NOTE...TAKING ANOTHER LOOK AT WINDS SUNDAY...THE GRADIENT
APPEARS TO RELAX FAST ENOUGH TO ALLOW THE WIND ADVY TO EXPIRE MUCH
EARLIER THAN PREVIOUSLY THOUGHT. WILL TRIM IT BACK TO END SATURDAY
EVENING.
AT 215 PM EST FRIDAY...A STRONG SHORTWAVE WILL DIVE INTO THE BASE OF
AN EASTERN NORTH AMERICAN TROUGH TONIGHT...REACHING THE CENTRAL
CAROLINAS BY SATURDAY MORNING. THIS SHORTWAVE WILL MOVE UP THE EAST
COAST ON SATURDAY.
MODEST ISENTROPIC UPGLIDE WILL SPREAD OVER THE MOUNTAINS ATE THIS
EVENING...AND THE FOOTHILLS AND PIEDMONT SHORTLY THEREAFTER...
SUPPORTING THE DEVELOPMENT OF PRECIPITATION AHEAD OF AN APPROACHING
COLD FRONT. MODEL SOUNDINGS SHOW MOISTURE EXTENDING TO LEVELS COLD
ENOUGH FOR ICE NUCLEATION...BUT LOWER LEVELS WILL INITIALLY BE WARM
ENOUGH FOR RAIN. WITH NO WARM NOSE ALOFT...THIS WILL BE A
RAIN/SNOW SETUP. AS THE NIGHT PROGRESSES...SNOW LEVELS FALL TO THE
FLOORS OF THE MOUNTAINS VALLEYS...AND BRIEFLY TO THE SURFACE IN THE
LEE OF THE MOUNTAINS...MAINLY IN WESTERN NC. MINIMUM TEMPERATURES
ARE EXPECTED TO BE NEAR NORMAL...AND ABOVE FREEZING EAST OF THE
MOUNTAINS. SNOW ACCUMULATIONS EAST OF THE BLUE RIDGE ARE NOT
EXPECTED.
FRONTAL PASSAGE BEFORE DAWN WILL BE FOLLOWED BY MOISTURE WRAPPING
AROUND A DEEPENING SURFACE LOW OVER THE INTERSTATE 77 CORRDIOR OF
NC. PRECIPITATION MAY LINGER IN THE WESTERN NC PIEDMONT FOR A FEW
HOURS AFTER DAYBREAK BEFORE THE SURFACE LOW MOVES OFF TO THE NE AND
TAKES THE MOISTURE WITH IT. A TRANSITION FROM SNOW TO RAIN IS
EXPECTED DURING THIS TIME FRAME.
GUSTY NW WINDS BEHIND THE FRONT MAY SUPPORT A WIND ADVISORY NEAR THE
BLUE RIDGE ON SATURDAY. MOIST NW FLOW SNOW WILL SET UP BEHIND THE
FRONT...WITH SNOW CONTINUING IN THE NC MOUNTAINS UNTIL DRYING AT
MIDDAY. MOST ACCUMULATIONS WILL BE ABOVE 3500 FEET...WHERE WINTER
WEATHER ADVISORY CRITERIA ARE EXPECTED TO BE MET. A FEW LOCATIONS
NEAR THE TN BORDER COULD RECEIVE FOUR TO FIVE INCHES...BUT THE
COVERAGE WOULD BE TOO CONFINED TO ISSUE A WARNING FOR THOSE
COUNTIES. HIGH TEMPERATURES SATURDAY WILL RUN SLIGHTLY BELOW NORMAL
IN THE LEE OF THE MOUNTAINS AS COLD ADVECTION OFFSETS DOWNSLOPE FLOW
WARMING. TEMPERATURES IN THE MOUNTAINS WOULD RUN ALMOST 12 DEGREES
BELOW NORMAL IN COLD ADVECTION.
&&
.SHORT TERM /SATURDAY NIGHT THROUGH MONDAY/...
AS OF 2 PM FRIDAY...WE BEGIN A WELL-DESERVED PERIOD OF RELATIVELY
QUIET WEATHER. ONE LAST SHORT WAVE IS EXPECTED TO DROP DOWN INTO THE
MEAN UPPER TROF OVER THE EAST ON SATURDAY NIGHT...AND IT WILL PASS
EARLY ON SUNDAY MORNING. THIS WAVE WILL BRING SOME MOISTURE DOWN
FROM THE NORTHWEST ON SUNDAY MORNING. THE LOW LEVEL FLOW AHEAD OF
THE WAVE WILL BE WESTERLY...SO ALTHOUGH WE WILL HAVE SOME MID LEVEL
FORCING WITH THE PASSAGE OF THE WAVE...THE LOW LEVELS WILL NOT BE
COOPERATIVE FOR PRECIP PRODUCTION ON THE TN BORDER. WE ARE CARRYING
A SLIGHT CHANCE POP OVER THE NORTHERN MTNS AND IT APPEARS THIS
SHOULD SUFFICE...FOR SNOW SHOWERS MAINLY SUNDAY MORNING. ONCE THAT
WAVE PASSES...THE UPPER PATTERN DEAMPLIFIES AND BEGINS A PERIOD OF
NEARLY ZONAL FLOW INTO MONDAY AND BEYOND. A SHORT WAVE MOVING UP THE
OH VALLEY ON MONDAY WILL DRAW MOISTURE FROM THE GULF WITH A
DEVELOPING SOUTHERLY UPSLOPE COMPONENT. THIS COULD FORCE SOME SHOWER
ACTIVITY OVER THE MTNS AND JUST E OF THE BLUE RIDGE IN THE AFTERNOON
AS THE MOISTURE INCREASES. OTHERWISE...WE ARE LOOKING AT TEMPS
SLOWLY MODERATING...WITH A RETURN TO NORMAL ON SUNDAY AND SUNDAY
NIGHT...AND THEN SLIGHTLY ABOVE NORMAL ON MONDAY.
&&
.LONG TERM /MONDAY NIGHT THROUGH FRIDAY/...
AS OF 210 PM EST FRIDAY...ZONAL FLOW ACROSS THE CONUS WILL GIVE WAY
TO AN RNA PATTERN LATER IN THE MEDIUM RANGE AS A TROUGH DIGS ACROSS
THE WRN US...INDUCING RIDGING OVER THE EAST.
MONDAY NIGHT A FAST MOVING SOUTHERN STREAM SHORT WAVE WILL CROSS THE
REGION. BASED ON THE LLVL TEMPERATURE PROFILE...PCPN WITH THIS
FEATURE SHOULD BE ALL RAIN. WITH THE BEST OF THE FORCING EXPECTED TO
PASS NORTH OF THE REGION...QPF SHOULD BE LIGHT WITH THE WAVE IN ANY
EVENT.
TEMPERATURES WILL WARM CONSIDERABLY ON TUESDAY WITH MAX TEMPS
EXPECTED TO RUN ABOUT 10 DEGREES ABOVE NORMAL ACROSS THE REGION. ON
WEDNESDAY THE LONG WAVE RIDGE WILL BEGIN TO BUILD ACROSS THE
SOUTHEAST STATES...YIELDING AN EVEN WARMER DAY. ONE POTENTIAL CAVEAT
IS THAT THE GFS SHOWS QUITE A BIT OF LLVL MOISTURE. AS WARM
ADVECTION INCREASES...AND THE COLD AIRMASS IS GRADUALLY DISPLACED
BY MUCH WARMER AIR...WE COULD SEE QUITE A BIT OF STRATUS TUESDAY AND
WEDNESDAY MORNINGS. THERE MAY BE SOME LIGHT SHOWER ACTIVITY OVER AND
NEAR THE BLUE RIDGE BY EARLY WEDNESDAY MORNING AS PW/S INCREASE TO
150-175 PERCENT OF NORMAL ON THE GFS.
SOUTHWESTERLY FLOW WILL BECOME STRONGER ON THURSDAY AS THE RIDGE
BUILDS AND A SHORT WAVE LIFTS ACROSS THE UPPER MID-WEST. THE
RESULTING INCREASE IN MOISTURE AND UPSLOPE FLOW MAY TRIGGER SHOWER
ACTIVITY OVER THE REGION...ESPECIALLY ACROSS THE MOUNTAINS AND
FOOTHILLS. THIS SEAMS REASONABLE AND WE HAVE SHOWERS OVER ALL BUT
THE SOUTHEAST TIER OF COUNTIES FOR THURSDAY.
THE LOW LIFTING ACROSS THE GREAT LAKES MAY PUSH A COLD FRONT INTO
THE REGION BY FRIDAY. WE WILL SEE JUST HOW FAR THAT BOUNDARY WILL
PUSH UNDER SOUTHWESTERLY FLOW ALOFT. THE ECMWF CAPE VALUES INCREASE
TO OVER 1000 J/KG OVER THE FOOTHILLS AND PIEDMONT. THE GFS DEWPOINTS
RISE INTO THE 60S...ALSO SUPPORTIVE OF DEEP CONVECTION. THEREFORE I
HAVE SHOWERS AND THUNDERSTORMS IN FOR FRIDAY. IT/S WAY TOO EARLY TO
ASCERTAIN THE SEVERE THREAT...THOUGH THE ANAFRONT NATURE OF THE
SYSTEM WOULD BE MORE SUPPORTIVE OF HEAVY RAIN OUT AT DAY 7 AND
BEYOND.
&&
.AVIATION /03Z SATURDAY THROUGH WEDNESDAY/...
AT KCLT...FAST MOVING SHORTWAVE TROUGH WILL PASS OVERHEAD EARLY
SATURDAY. CIGS ARE EXPECTED TO LOWER TO MVFR AS PRECIP MOVES THRU
AHEAD OF THIS WAVE IN THE PREDAWN HOURS...PER GFS/NAM RH PROFILES
AND UPSTREAM OBS. MESOSCALE GUIDANCE SUGGESTS THE PRECIP WILL BE
CAPABLE OF MVFR VSBY AS WELL...BUT SFC RH AND MODEST SWLY WINDS
SHOULD KEEP FOG FROM DEVELOPING SO THE VSBY MENTION IS IN TEMPO.
THERMAL PROFILE SUGGESTS RAIN...WITH A VERY BRIEF PERIOD OF A RA/SN
MIX POSSIBLE AS LLVL WAA ENDS FOLLOWING THE DEPARTURE OF THE WAVE
JUST AFTER DAYBREAK...BUT PRECIP IS LIKELY TO DIMINISH BEFORE THE
COLDER AIR ARRIVES. WINDS SHIFT TO NWLY THEREAFTER...BECOMING GUSTY
AS SKIES BECOME MOSTLY CLEAR.
ELSEWHERE...MVFR CIGS MOVE IN BY LATE EVENING IN THE WEST WITH
PRECIP FOLLOWING MAINLY AFTER MIDNIGHT. MOST SITES STAND TO SEE 2-3
HRS OF STEADY PRECIP WITH GUIDANCE INDICATIVE OF MVFR VSBY. SNOW
LEVELS WILL DROP IN THE MTNS/FOOTHILLS AS THE BASE OF THE TROUGH
SWINGS THRU AND LLVL CAA GETS UNDERWAY...AND WINDS SHIFT TO NW. THIS
SHOULD GIVE KAVL/KHKY A PERIOD OF -SN BEFORE PRECIP TAPERS OFF...BUT
ANY ACCUMULATING SNOW SHOULD ONLY AMOUNT TO A DUSTING AT THESE
SITES. KHKY MAY NOT SEE ANY ACCUM WITH -RA LIKELY TO MIX IN.
CLEARING TREND BEGINS AROUND DAYBREAK...EXCEPT KAVL MAY SEE LOW
CLOUDS HANG ON FOR A TIME AS NW UPSLOPE FLOW CONTINUES INTO THE
MTNS. MODERATE GUSTS OF UP TO 30 KT AROUND THE AREA TOMORROW. WIND
ADVY IN EFFECT FOR THE ERN BLUE RIDGE AREAS SAT...INCLUDING KAVL.
OUTLOOK...VFR BUT BREEZY CONDITIONS ARE EXPECTED SATURDAY NIGHT THRU
THE WEEKEND. PRECIP OR LOW CIGS MAY RETURN WITH A FRONTAL PASSAGE
MONDAY NIGHT. THE SOUTHEAST U.S. SHOULD SEE A SPRINGLIKE WARM AND
WET PATTERN LATER IN THE WEEK...WITH SHRA/TSRA CAUSING SPOTTY
RESTRICTIONS.
CONFIDENCE TABLE...
02-08Z 08-14Z 14-20Z 20-02Z
KCLT HIGH 91% MED 75% HIGH 92% HIGH 100%
KGSP MED 78% HIGH 90% HIGH 100% HIGH 100%
KAVL MED 71% MED 72% HIGH 100% HIGH 100%
KHKY MED 70% HIGH 91% HIGH 100% HIGH 100%
KGMU HIGH 81% HIGH 92% HIGH 100% HIGH 100%
KAND HIGH 84% HIGH 98% HIGH 100% HIGH 100%
THE PERCENTAGE REFLECTS THE NUMBER OF GUIDANCE MEMBERS AGREEING
WITH THE SCHEDULED TAF ISSUANCE FLIGHT RULE CATEGORY. COMPLETE
HOURLY EXPERIMENTAL AVIATION FORECAST CONSISTENCY TABLES AND ENSEMBLE
FORECASTS ARE AVAILABLE AT THE FOLLOWING LINK: (MUST BE LOWER CASE)
WWW.WEATHER.GOV/GSP/AVIATION_TABLES
&&
.GSP WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
NC...WIND ADVISORY FROM 6 AM TO 6 PM EST SATURDAY FOR NCZ033-049-
050-052-053-064-065-501-503-505-507-509.
WINTER WEATHER ADVISORY UNTIL 1 PM EST SATURDAY FOR NCZ033-
048>052-058-059-062-063.
SC...WIND ADVISORY FROM 6 AM TO 6 PM EST SATURDAY FOR SCZ003.
&&
$$
SYNOPSIS...JAT
NEAR TERM...JAT/WIMBERLEY
SHORT TERM...PM
LONG TERM...MCAVOY
AVIATION...WIMBERLEY
AREA FORECAST DISCUSSION
NWS SIOUX FALLS SD
432 AM CST THU FEB 13 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 430 AM CST THU FEB 13 2014
UPPER WAVE PASSING BY TO OUR NORTH WILL PUSH A COLD FRONT THROUGH
OUR AREA TODAY. SEEING SOME AREAS OF BLOWING SNOW ACROSS SOUTHWEST
MINNESOTA EARLY THIS MORNING. EXPECT WINDS TO TURN WESTERLY AND THEN
NORTHWESTERLY THIS MORNING BEHIND THE COLD FRONT. WITH A STRONG PUSH
OF COLD AIR ADVECTION AND 30 TO 40 KTS AT 925 MB...WOULD EXPECT
WINDS TO PICK UP AGAIN BEHIND THIS FRONT BY MID MORNING...STRONGEST
EAST OF INTERSTATE 29. THINKING WE SEE 20 TO 35 MPH WITH A FEW GUSTS
UP TO 45 MPH. THUS THINK AREAS OF BLOWING AND DRIFTING SNOW WITH
REDUCED VISIBILITIES WILL CONTINUE ACROSS SOUTHWEST MINNESOTA...SO
THE WINTER WEATHER ADVISORY LOOKS IN GOOD SHAPE. WILL PROBABLY SEE
SOME BLOWING SNOW INTO NORTHWEST IOWA AS WELL LATER THIS
MORNING...BUT NOT SURE VISIBILITY WILL BE REDUCED TO WARRANT AN
ADVISORY...THUS WILL LEAVE THEM OUT FOR NOW AND LET DAY SHIFT
MONITOR TRENDS. WINDS WILL BEGIN TO TAPER OFF MID TO LATE AFTERNOON
WHICH SHOULD LEAD TO THE ABATEMENT OF THE THE BLOWING SNOW. WILL SEE
MORNING HIGHS NORTH OF THE MISSOURI RIVER WITH FALLING TEMPERATURES
FROM NORTH TO SOUTH. AREAS ALONG THE MISSOURI RIVER WILL SEE HIGHS
LATER THIS MORNING AND EARLY AFTERNOON....WITH FALLING TEMPERATURES
HOLDING OFF UNTIL LATER THIS AFTERNOON AND EVENING. COLD AIR PUSH
CONTINUES TO LOOK STRONGER ON NEW MODEL RUNS. THUS MAIN CHANGE WAS
TO SPEED UP THE DROPPING TEMPERATURES TODAY INTO TONIGHT...THUS
LEADING TO COLDER LOW TEMPERATURES. FAVORED A BLEND OF THE
GFS...ECMWF AND GEM REGIONAL FOR TEMPERATURE TRENDS TODAY INTO
TONIGHT.
OTHER WEATHER FEATURE WILL BE OUR NEXT CLIPPER DROPPING SOUTHEAST IN
THE NORTHWEST FLOW TONIGHT. IT IS A PRETTY STRONG SHORTWAVE...WITH
GOOD PV ADVECTION...AND LARGE SCALE FORCING IN THE LEFT EXIT OF AN
UPPER JET. SIMILAR LARGE SCALE FORCING AS TO WHAT WE SAW THE OTHER
NIGHT. THE DIFFERENCE WITH THIS SYSTEM IS THAT THE THE MID LEVEL
FRONTAL BOUNDARY AND FRONTOGENESIS SHOULD BE IN A WEAKENING STATE AS
IT MOVES ACROSS THE CWA. THUS THE HIGHEST SNOW AMOUNTS WILL LIKELY
BE NORTHWEST OF THE CWA...WITH THE BAND OF SNOW IN A WEAKENING AND
DISSIPATING STATE AS IT MOVES ACROSS THE CWA. QUITE A BIT OF DRY AIR
WILL AGAIN HAVE TO BE OVERCOME...BUT GIVEN THE STRENGTH OF THE WAVE
STILL SEEMS LIKE A FEW HOUR PERIOD OF SNOW IS LIKELY. BASED ON
LATEST TRENDS DID NUDGE THE HIGHEST POPS TO THE NORTH SOME AND
SLOWED DOWN THE TIMING...BUT OTHERWISE PREVIOUS FORECAST LOOKED
GOOD. GIVEN THE WEAKENING NATURE OF THE FRONT THINKING AMOUNTS WILL
PROBABLY END UP SOMEWHERE BETWEEN A HALF INCH TO 1 INCH OR LESS
OVER A MAJORITY OF THE AREA. THE BEST CHANCE OF SEEING ISOLATED
AMOUNTS OF 1.5 TO POSSIBLY 2 INCHES WOULD APPEAR TO BE IN OUR
NORTHWEST AREAS THIS TIME AROUND...IN THE HURON VICINITY.
.LONG TERM...(FRIDAY THROUGH WEDNESDAY)
ISSUED AT 430 AM CST THU FEB 13 2014
SOME LINGERING LIGHT SNOWFALL COULD CONTINUE EARLY MORNING MAINLY
LOWER MISSOURI VALLEY THROUGH PARTS OF NORTHWEST IOWA...AND DID
STRETCH A SLIGHT CHANCE BACK A BIT FURTHER WESTWARD ALONG THE
TIGHT LOW LEVEL THERMAL GRADIENT WHICH WILL CONTINUE TO BACK
SLOWLY SOUTHWESTWARD THROUGH MUCH OF THE DAY. COOLER AIR WILL
CONTINUE TO DRIVE SOUTHWARD ON FRIDAY BEHIND EXITING WAVE...WITH
WEAK SURFACE RIDGE BUILDING INTO SOUTHWEST MINNESOTA AND NORTHWEST
IOWA BY EVENING. INCREASED POTENTIAL FOR BAND OF LOWER CLOUDS
WITHIN THIS ZONE AND FOR THE MOMENT HAVE RESISTED TEMPTATION TO
PERSIST A FEW FLURRIES FOR MUCH OF THE DAY...ESPECIALLY LATE AS
SOME WEAK LIFT TOWARD TOP OF TRAPPED MOISTURE LAYER DEVELOPS WITH
START OF WARM AIR ADVECTION.
FRIDAY NIGHT ANOTHER CLIPPER WAVE AND STRONG JET STREAK WILL BEGIN
TO DIG SOUTHEAST INTO THE NORTHERN PLAINS. STRONG WARM AIR ADVECTION
ZONE IN PLACE...AND WILL INCREASINGLY BRING A CHANCE FOR LIGHT
PRECIPITATION AS IT SPREADS EASTWARD TOWARD I 29. WHILE A MAJORITY
OF THE PRECIPITATION THREAT WILL BE CONTAINED IN A COOLER ZONE
EITHER BY AIR MASS OR EVAPORATIVE COOLING...THE WESTERN SECTION OF
ANY PRECIP AREA WILL LIKELY REMAIN JUST WARM ENOUGH ALOFT FOR
MELTING AND ALLOW A SMALL THREAT FOR FREEZING RAIN AS FAR EAST AS
AREAS TOWARD I 29 BY EARLY SATURDAY MORNING. TEMPS AGAIN WILL
TREND NON DIURNAL FOR MOST...PERHAPS WARMING TO NEAR FREEZING IN
SOUTH CENTRAL SD. MOST WIDESPREAD PRECIPITATION WILL GRADUALLY
ENGAGE SOUTHWEST MINNESOTA...AND SHOULD REMAIN COOL ENOUGH WITH A
STRONG FRONTAL CIRCULATION TO MAINTAIN ALL SNOW FURTHER EAST. MOST
AREAS SHOULD SEE PRECIP ALL BUT DONE BY SATURDAY AFTERNOON...BUT
LOWER LEVEL MOISTURE AND COOLING WRAPPING SOUTHWARD BEHIND CLIPPER
COULD MAINTAIN A LIGHT SNOW THREAT FOR FAR NORTHEAST AREAS UNTIL
EARLY EVENING.
YET ANOTHER WEAK COOLER PUSH WILL FOLLOW ON SATURDAY NIGHT INTO
EARLY SUNDAY...BUT THIS ONE WILL BE FOCUSED MAINLY EAST...AND WILL
GIVE WAY EVEN QUICKER TO A STRONG SOUTHERLY RETURN FLOW AS HEIGHTS
CONTINUE TO RISE ACROSS THE NORTHERN PLAINS. WAVE PUSHING ACROSS
THE NORTHERN PORTIONS OF THE REGION WILL START DIGGING IN ON
SUNDAY NIGHT...AND WHILE MOISTURE WILL BE SOMEWHAT LACKING AND
WHOLE TROUGH APPEARS SOMEWHAT SPLITTY FROM A PV PERSPECTIVE...
SHOULD BE ENOUGH IN THE MID LEVEL FRONTAL ZONE FOR FOCUSED LIFT TO
SATURATE FOR SOME LIGHT PRECIPITATION. BEST THREAT FOR PRECIP
ACROSS THE NORTH WITH STRONGER PV/FRONTAL INTERACTION. PRECIP
TYPE IS DIFFICULT WITH DRY AIR AGAIN LEAVING ROOM FOR SOME
EVAPORATIVE COOLING...BUT LIGHT RATES ARE LIKELY TO MAKE EVEN
THIS SOMEWHAT AN INEFFECTIVE PROCESS. SHOULD SEE SOME SPOTTY FZRA
OR SLEET FOR MUCH OF THE AREA...BUT TEMPS TO THE WEST SHOULD
REMAIN NEAR OR ABOVE FREEZING OVERNIGHT.
MONDAY THROUGH WEDNESDAY ARE LIKELY TO BE THE WARMEST DAYS OF THE
UPCOMING WEEK...ESPECIALLY THE TWO LATTER DAYS. TEMPERATURES ARE
TOUGH IN THAT ONCE SNOW MELTS AWAY...OR FLOW BECOMES OFF AREAS
THAT ARE SNOW FREE...TEMPS FROM MIXING OF MODELS WHICH MAY ALSO BE
IMPACTED BY SOME DEGREE BY CURRENT SNOW COVER FIELDS. DISTRIBUTION
OF ENSEMBLE SOLUTIONS FAVORS FOLLOWING THE WARMER SIDE OF
SOLUTIONS...AND EVEN THE SLIDING TOWARD THE 90TH PERCENTILE
SOLUTION COMES UP SHORT OF 925 HPA MIXING. SHOULD REMAIN A DRY
PERIOD... BUT SEVERAL MODELS HINT THAT INCREASING LOW LEVEL
MOISTURE BY WEDNESDAY SNEAKING INTO THE EASTERN CWA MAY THREATEN A
FEW MORE LOWER CLOUDS.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z THURSDAY NIGHT)
ISSUED AT 1030 PM CST WED FEB 12 2014
LOWS CLOUDS ARE STILL ACROSS SW MN AND NW IA AS OF 04Z BUT THEY
HAVE BEGUN TO SLOWLY MOVE NORTHEAST IN RESPONSE TO INCREASING SW
FLOW JUST ABOVE THE SURFACE AND DO NOT EXPECT THESE TO MOVE BACK
INTO SIOUX CITY OR SIOUX FALLS THE REMAINDER OF THE NIGHT. THERE
MAY BE SOME STRATOCU THAT FORMS BEHIND THE SURFACE COLD FRONT LATE
TOMORROW MORNING AND AFTERNOON ALONG AND NORTH OF I-90...INCLUDING
KFSD AND KHON. ONLY THE NAM...WHICH HAS A TENDENCY TO OVERDO LOW
CLOUDS...SHOWS BROKEN SKIES WHILE THE GFS AND RAP ARE MORE
OPTIMISTIC. SO ONLY INCLUDED A SCATTERED DECK AT THIS POINT BUT
WILL NEED TO MONITOR FOR THE POSSIBILITY THAT CLOUDS WILL BE MORE
WIDESPREAD. OTHERWISE...VFR CONDITIONS EXPECTED AT ALL 3 TAF
SITES THROUGH 00Z FRI. WINDS HOWEVER MAY BE A PROBLEM. TONIGHT
WINDS GUSTING TO 25 KTS ARE EXPECTED OUT OF THE SOUTH. THEN AFTER
THE COLD FRONT MOVES THROUGH TOMORROW MORNING...NORTHWEST WINDS
WILL ALSO GUST TO NEAR 30 KTS THROUGH MID AFTERNOON. WINDS SHOULD
RAPIDLY DECREASE TOWARD SUNSET AS A WEAK RIDGE MOVES IN. CLOUDS
WILL ALSO BE MOVING OVERHEAD AS THE NEXT WAVE APPROACHES. THROUGH
06Z...ONLY EXPECT MVFR AT KHON. BUT AFTER 06Z...ALL THREE SITES
LIKELY TO SEE CIGS BELOW 3000 FT AND VSBYS MAY FALL BELOW 3SM DUE
TO DEVELOPING LIGHT SNOW.
&&
.FSD WATCHES/WARNINGS/ADVISORIES...
SD...WINTER WEATHER ADVISORY UNTIL 3 PM CST THIS AFTERNOON FOR SDZ040.
MN...WINTER WEATHER ADVISORY UNTIL 3 PM CST THIS AFTERNOON FOR MNZ071-
072-080-081-089-090-097.
IA...NONE.
NE...NONE.
&&
$$
SHORT TERM...CHENARD
LONG TERM...CHAPMAN
AVIATION...SCHUMACHER
AREA FORECAST DISCUSSION
NWS SIOUX FALLS SD
1030 PM CST WED FEB 12 2014
.UPDATE...
ISSUED AT 837 PM CST WED FEB 12 2014
00Z SOUNDING AT KABR SHOWS 30 TO 40 KTS ABOVE 900 MB THIS EVENING
AS LOW LEVEL JET BEGINS TO DEVELOP. WITH A FAIRLY STRONG INVERSION
SET UP OVER THE BUFFALO RIDGE AND STRONG FLOW PERPENDICULAR TO THE
RIDGE LINE...ATMOSPHERE IS SET UP FOR DEVELOPMENT OF DOWNSLOPE WINDS
IN THE VICINITY OF THE BUFFALO RIDGE OVERNIGHT. ALL HIGH RES
MODELS SHOW GUSTS APPROACHING 35 MPH AFTER MIDNIGHT AND WOULD NOT
BE SURPRISED TO SEE GUSTS OVER 40 MPH FOR A BRIEF PERIOD TONIGHT.
WITH 1 TO 1.5 INCHES OF NEW SNOW...EXPECT BLOWING SNOW TO DEVELOP
WITH THE WORST CONDITIONS FROM NORTH OF IVANHOE MN TO NEAR MML
AND TRACY AND DOWN TOWARD SLAYTON AND WINDOM. WHILE VISIBILITIES
NEAR 1/2 MILE WILL PREDOMINATE...THERE WILL LIKELY BE PERIODS WITH
WHITE OUT CONDITIONS JUST NORTHEAST OF THE RIDGE LINE WEST OF
MARSHALL AND TRACY. SINCE WE ARE NOT EXPECTING WIDESPREAD WHITE
OUT CONDITIONS FOR SEVERAL HOURS...DID NOT ISSUE A BLIZZARD
WARNING BUT DRIVING COULD BE DIFFICULT AT TIMES LATE TONIGHT. WHILE
THE WINTER WEATHER ADVISORY DOES INCLUDE BROOKINGS
COUNTY...BLOWING SNOW TONIGHT IS EXPECTED TO BE CONFINED TO THE
NORTHEAST PORTION OF THE COUNTY AND SHOULD NOT AFFECT THE CITY OF
BROOKINGS. THE WINDS WILL BRIEFLY DIMINISH AS THE COLD FRONT GOES
THROUGH EARLY TOMORROW MORNING BUT EXPECT NORTHWEST WINDS TO
INCREASE BY LATE MORNING.THEY WON`T BE QUITE AS STRONG ALONG THE
RIDGE AS TONIGHT...BUT FOR PLACES AWAY FROM THE RIDGE THESE WINDS
MAY ACTUALLY BE STRONGER...WITH GUSTS OVER 30 MPH FROM BROOKINGS
DOWN TO JACKSON AND WORTHINGTON. WITH COLD AIR ADVECTION KEEPING
THE SURFACE LAYER WELL MIXED...IT SHOULD ALSO BE EASIER TO LOFT
SNOW DURING LATE MORNING AND THE AFTERNOON. CONDITIONS SHOULD
IMPROVE BY MID AFTERNOON.
AS FOR TEMPERATURES...THERE IS EVERY INDICATION THAT TEMPERATURES
WILL RISE MOST OF THE NIGHT AND INTO TOMORROW MORNING. WOULD NOT
BE SURPRISED IF SOME PLACES IN SOUTH CENTRAL SOUTH DAKOTA REACH
THE UPPER 40S AND MAY EVEN REACH 40 AS FAR EAST AS SIOUX FALLS
EARLY THURSDAY MORNING. BUT CONFIDENCE IS LOW ON BOTH HOW
EFFECTIVE MIXING WILL BE JUST BEHIND THE FRONT AND HOW QUICK THE
COLD AIR WILL COME IN. SO HAVE TEMPERATURES ONLY RISE LATE
TONIGHT AND TOMORROW INTO THE MID 30S NORTH OF I90 TO THE LOWER
40S IN THE MISSOURI VALLEY. AFTER THE FRONT MOVES THROUGH...SW MN
AND FAR ERN SD WILL SEE TEMPERATURES SLOWLY FALL ALL DAY. IN THE
MISSOURI VALLEY...THE FRONT MAY SLOW UP SO THAT THE COLDEST AIR
CANNOT REALLY GET THAT FAR SOUTH AND THIS WILL ALLOW TEMPERATURES
IN THE AFTERNOON TO REMAIN IN THE LOWER 40S.
&&
.SHORT TERM...(THIS EVENING THROUGH THURSDAY)
ISSUED AT 316 PM CST WED FEB 12 2014
HORT WAVE APPROACHING FROM THE CANADIAN ROCKIES LOOKS TO BE FAR
ENOUGH NORTH TO KEEP ANY LIGHT PRECIPITATION NORTH OF OUR FORECAST
AREA TONIGHT. THERE WILL BE SOME MIDDLE AND HIGH CLOUDS SPREADING
OVER THE AREA...BUT THE MAIN FEATURE AFFECTING OUR WEATHER WILL BE
THE INCREASING SOUTHERLY AND SOUTHWESTERLY WINDS. THE WINDS WILL
SHOW THEIR GREATEST INCREASE OVER THE FAVORED BUFFALO RIDGE AREA IN
SOUTHWEST MINNESOTA...AND THAT IS WHERE THE DEVELOPMENT OF BLOWING
SNOW WILL BE THE GREATEST. ENOUGH NEW SNOW FELL LAST NIGHT TO RESULT
IN GREATER VISIBILITY REDUCTIONS WITH THE BLOWING SNOW THAN WITH
YESTERDAYS SUB ADVISORY EVENT. A WINTER WEATHER ADVISORY WILL BE
ISSUED FOR THIS AREA...INCLUDING MOST OF SOUTHWEST MINNESOTA AND
BROOKINGS COUNTY. AFTER THE WINDS SWING TO WESTERLY AND DECREASE BY
MORNING...THEY WILL PICK UP AGAIN FROM THE WEST TO NORTHWEST
THURSDAY MORNING AND CONTINUE INTO THE AFTERNOON. THESE WINDS WILL
BE MORE GENERAL OVER THE NORTHERN PART OF THE FORECAST AREA...AND
NOT AS STRONG AS THE MORE LOCALIZED WINDS TONIGHT. THEREFORE...WILL
MENTION BLOWING SNOW IN OTHER PARTS OF THE NORTHERN AND EAST CENTRAL
FORECAST AREA...DOWN TO THE SPENCER IOWA AREA...AND NOT GO WITH AN
ADVISORY. HOWEVER...THESE WINDS ARE LIKELY TO BE A LITTLE STRONGER
IN SOUTHWEST MINNESOTA...THOUGH THE EFFECT WILL NOT BE NEARLY AS
STRIKINGLY LOCAL AS WITH THE SOUTHWESTERLY WINDS TONIGHT. WILL
THEREFORE KEEP THE ABOVE MENTIONED ADVISORY GOING INTO MID AFTERNOON
THURSDAY...AFTER WHICH THE WINDS WILL BE ON A CLEAR DECREASE.
TEMPERATURES WILL DROP A LITTLE BY EARLY EVENING IN THE STILL LIGHT
WIND AREA FAR EAST...OTHERWISE THEY SHOULD BE WARMING MOST OF THE
NIGHT. AS THE SHORT WAVE PASSES BY TO THE NORTH LATER
TONIGHT...SKIES SHOULD BECOME PRETTY CLEAR BY THE MIDDLE OF THURSDAY
MORNING. A CLOUD INCREASE WILL THEN START UP THURSDAY AFTERNOON AS
THE NEXT SYSTEM APPROACHES. TEMPERATURES THURSDAY WILL SHOW SOME
WARMING FROM THE EARLY MORNING MILD READINGS SOUTH...ESPECIALLY
SOUTHWEST...WHILE SOME COOLING STARTS NORTH BEHIND TONIGHTS WAVE. AT
THIS TIME DO NOT SEE THE NEXT SYSTEM ARRIVING SOON ENOUGH TO
THREATEN PRECIPITATION BY THE END OF THURSDAY DAYTIME.
.LONG TERM...(THURSDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 316 PM CST WED FEB 12 2014
THE BARRAGE OF WEAK WAVES CONTINUES INTO THURSDAY NIGHT WITH
SHORTWAVE DROPPING SOUTHEAST ACROSS WESTERN INTO SOUTH CENTRAL SOUTH
DAKOTA. UPPER LEVEL DIV Q POSITIONED FURTHER TO THE EAST...BUT
WHERE THE MID AND UPPER LEVEL DYNAMICS COME TOGETHER EXPECT BAND OF
SNOW. FORTUNATELY...MODELS HAVE COOLED IN TERMS OF TEMPERATURES
ALOFT SO AM NOT THINKING MIXED PRECIPITATION IS A THREAT. HAVE
SHIFTED THE BAND OF SNOW FURTHER TO THE WEST CLOSER TO THE MID LEVEL
WAVE. EXPECT PRECIPITATION TO QUICKLY WORK OUT OF THE AREA ON
FRIDAY MORNING WITH SUNSHINE AND LIGHT WINDS FOLLOWING. WITH COOL
AIRMASS HANGING AROUND THE AREA...MOST SIGNIFICANT WARMING WILL BE
WEST OF THE JAMES RIVER VALLEY.
NEXT DISTURBANCE APPROACHES FROM THE WEST NORTHWEST SATURDAY
MORNING. INCREASED POPS WITH THIS FEATURE...THOUGH APPEARS AS
THOUGH MOISTURE WILL BE SOMEWHAT LIMITED WITH THIS SYSTEM WITH ONLY
A FEW HOURS OF SATURATION IN ANY GIVEN LOCATION. STILL COULD SEE A
QUICK INCH OF SNOW WITH SNOW WATER EQUIVALENTS AROUND 15:1. SNOW IS
EXPECTED TO LINGER IN THE EAST THROUGH THE MORNING HOURS ON
SATURDAY. SKIES WILL GRADUALLY BECOME PARTLY CLOUDY AND WITH
TEMPERATURES WARMING ALOFT...EXPECT DECENT TEMPERATURE RECOVER
THROUGH THE AFTERNOON HOURS. MODELS SUGGEST IT MAY BECOME A LITTLE
BREEZY ACROSS CENTRAL SOUTH DAKOTA...WHILE WINDS REMAIN LIGHTER
FURTHER TO THE EAST CLOSER TO THE BOUNDARY.
FAIRLY SOLID WARMING IS EXPECTED ON SUNDAY AND THEN AGAIN ON
TUESDAY. EXTENDED GUIDANCE SHOWING MIXED SIGNALS...BUT TENDED TO
LEAN STRONGER ON THE ECMWF GUIDANCE WHICH WOULD SUGGEST TO ERR ON
THE WARMER SIDE OF GUIDANCE. TROUGH MOVES THROUGH THE AREA SUNDAY
NIGHT...AND ADDED SOME SLIGHT CHANCE POPS ACROSS THE NORTH WITH THIS
FEATURE CLOSER TO THE MID LEVEL WAVE. STILL A QUESTION AS TO
WHETHER ENOUGH MOISTURE WOULD BE AVAILABLE FOR THIS WAVE...SO WAS
PRETTY CONSERVATIVE WITH POPS.
COOL AND BREEZY NORTHWEST WINDS EXPECTED ON MONDAY. HAVE INCREASED
WINDS OVER GUIDANCE...THOUGH THEY SHOULD SLOWLY DECREASE THROUGHOUT
THE DAY.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z THURSDAY NIGHT)
ISSUED AT 1030 PM CST WED FEB 12 2014
LOWS CLOUDS ARE STILL ACROSS SW MN AND NW IA AS OF 04Z BUT THEY
HAVE BEGUN TO SLOWLY MOVE NORTHEAST IN RESPONSE TO INCREASING SW
FLOW JUST ABOVE THE SURFACE AND DO NOT EXPECT THESE TO MOVE BACK
INTO SIOUX CITY OR SIOUX FALLS THE REMAINDER OF THE NIGHT. THERE
MAY BE SOME STRATOCU THAT FORMS BEHIND THE SURFACE COLD FRONT LATE
TOMORROW MORNING AND AFTERNOON ALONG AND NORTH OF I-90...INCLUDING
KFSD AND KHON. ONLY THE NAM...WHICH HAS A TENDENCY TO OVERDO LOW
CLOUDS...SHOWS BROKEN SKIES WHILE THE GFS AND RAP ARE MORE
OPTIMISTIC. SO ONLY INCLUDED A SCATTERED DECK AT THIS POINT BUT
WILL NEED TO MONITOR FOR THE POSSIBILITY THAT CLOUDS WILL BE MORE
WIDESPREAD. OTHERWISE...VFR CONDITIONS EXPECTED AT ALL 3 TAF
SITES THROUGH 00Z FRI. WINDS HOWEVER MAY BE A PROBLEM. TONIGHT
WINDS GUSTING TO 25 KTS ARE EXPECTED OUT OF THE SOUTH. THEN AFTER
THE COLD FRONT MOVES THROUGH TOMORROW MORNING...NORTHWEST WINDS
WILL ALSO GUST TO NEAR 30 KTS THROUGH MID AFTERNOON. WINDS SHOULD
RAPIDLY DECREASE TOWARD SUNSET AS A WEAK RIDGE MOVES IN. CLOUDS
WILL ALSO BE MOVING OVERHEAD AS THE NEXT WAVE APPROACHES. THROUGH
06Z...ONLY EXPECT MVFR AT KHON. BUT AFTER 06Z...ALL THREE SITES
LIKELY TO SEE CIGS BELOW 3000 FT AND VSBYS MAY FALL BELOW 3SM DUE
TO DEVELOPING LIGHT SNOW.
&&
.FSD WATCHES/WARNINGS/ADVISORIES...
SD...WINTER WEATHER ADVISORY UNTIL 3 PM CST THURSDAY FOR SDZ040.
MN...WINTER WEATHER ADVISORY UNTIL 3 PM CST THURSDAY FOR MNZ071-072-
080-081-089-090-097.
IA...NONE.
NE...NONE.
&&
$$
UPDATE...SCHUMACHER
SHORT TERM...
LONG TERM...
AVIATION...SCHUMACHER
AREA FORECAST DISCUSSION
NWS MILWAUKEE/SULLIVAN WI
342 PM CST THU FEB 13 2014
.SHORT TERM...
TONIGHT...FORECAST CONFIDENCE MEDIUM.
WILL KEEP SMALL POPS FOR PATCHY FLURRIES AND FREEZING DRIZZLE INTO
THE EARLY EVENING AS STRONG COLD FRONT MOVES THROUGH SOUTHERN WI.
IR TEMPERATURE ENHANCEMENT AND RAP SOUNDINGS SHOW LIMITED ICE
FALLING INTO THE CLOUD LAYER AT FIRST. SHEAR NEAR THE TOP OF THE
LAYER MAY BE ENOUGH TO SHAKE OUT SOME FREEZING DRIZZLE OR DRIZZLE IF
TEMPERATURES BRIEFLY WARM ABOVE FREEZING. OTHERWISE...STRONG
SYNOPTIC SCALE LIFT ASSOCIATED WITH HEAVY SHSN EARLIER TODAY
CONTINUES TO PUSH EAST OF SRN WI. A BRISK NIGHT LIES AHEAD WITH
STRONG LOW LEVEL COLD AIR ADVECTION AND 6 HOUR PRESSURE RISE OF 3 TO
5 MB AFFECTING THE AREA THIS EVENING. WILL BE INCREASING PREVAILING
WINDS AND WIND GUSTS FOR THE EVENING HOURS TO 15 TO 25
MPH...DECREASING TO 10 TO 15 MPH LATER TONIGHT AS PRESSURE RISE AREA
SLIDES EAST. WITH FRESH FALLEN SNOW...WL ADD PATCHY BLOWING SNOW
FOR THE EVENING HOURS TO ACCOUNT FOR GUSTS AT OR ABOVE 25 MPH.
INCREASING SUBSIDENCE AND DRIER AIR SHOULD RESULT IN AT LEAST
PARTIAL CLEARING OVERNIGHT. 4KM NCEP WRF-NMM HAS DECREASING COLUMN
CONDENSATE LATER IN THE EVENING...HOWEVER MORE MID-HIGH CLOUDS
SHOULD ROLL IN FROM THE NORTHWEST FROM NEXT SYNOPTIC SCALE SYSTEM.
85H TEMPS FALL BACK TO AROUND 10C RESULTING IN OVERNIGHT TEMPS
DIPPING ONCE AGAIN INTO THE SINGLE DIGITS ABOVE ZERO MOST LOCATIONS.
.FRIDAY...FORECAST CONFIDENCE MEDIUM.
SHORT TERM GUIDANCE IN GOOD AGREEMENT ON THE SYNOPTIC SCALE FORCING
ASSOCIATED WITH NEXT UPSTREAM SHORT WAVE OVER NORTHERN MT REMAINS
JUST TO THE SOUTHWEST OF SOUTHERN WI LATE TONIGHT THROUGH FRIDAY
MORNING. FLURRIES MAY NEAR SOUTHWEST CWA BORDER DURING THE MORNING
BUT THINKING SHOULD REMAIN JUST TO THE SOUTHWEST. OTHERWISE...COLD
AIR OVER SOUTHERN WI REINFORCED BUT SMALL SURGE OF COLD AIR
ADVECTION BEHIND SHORT WAVE. HENCE DAYTIME TEMPS ON FRIDAY TO
REMAIN WELL BELOW NORMAL FOR MID-FEBRUARY.
.FRIDAY NIGHT THROUGH SUNDAY...FORECAST CONFIDENCE MEDIUM.
A SURFACE RIDGE WITH CLEARING SKIES WILL SETTLE OVER THE REGION
FOR FRI NT WITH BELOW ZERO TEMPS EXPECTED FOR MOST LOCATIONS. ANOTHER
LOW PRESSURE AREA WITHIN NW FLOW ALOFT WILL THEN APPROACH FROM
THE DAKOTAS. A CONSENSUS OF MODELS HAS THE SHORTWAVE TROUGH AND
WEAKENING SFC LOW TRACKING TO CENTRAL IA BY 00Z SUN AND BECOMING A
BROAD AND WEAK LOW BY 12Z SUN OVER THE OHIO RIVER VALLEY. THE BEST
LIFT AND QPF IS OVER THE SW CWA WITH WEAKENING LIFT AND LOWER QPF
AS THE SYSTEM MOVES SEWD. LOW TO MID LEVEL WARM
ADVECTION...FRONTOGENESIS AIDED BY PVA ALOFT WILL START THE SNOW
MAINLY SAT AFTERNOON AND CONTINUE INTO THE EVENING. THE SNOW
ACCUM FORECAST RANGES FROM 0.5-1.0 INCHES OVER EAST CENTRAL WI TO
2 INCHES SW OF MADISON. MORE SNOW WOULD OCCUR IF THE SYSTEM
WEAKENING IS DELAYED. ANOTHER SFC RIDGE WILL THEN SETTLE OVER WI
FOR SUN. BELOW NORMAL TEMPS WILL CONTINUE THROUGH THE WEEKEND.
.LONG TERM...
SUNDAY NIGHT THROUGH THURSDAY...FORECAST CONFIDENCE LOW TO MEDIUM
A BROAD AND MORE ZONAL JET STREAM WILL DEVELOP FOR THE FIRST HALF
OF THE NEW WEEK AND THEN TRANSITION TO SWLY FLOW ALOFT AS A POLAR
TROUGH DIGS INTO THE WRN USA. THUS ABOVE NORMAL TEMPS ARE
EXPECTED. A SHORTWAVE TROUGH AND DEVELOPING SFC LOW WILL AFFECT
SRN WI MAINLY ON MONDAY WITH SLY FLOW AND WARM ADVECTION POSSIBLY
RESULTING IN A WARM LAYER ALOFT AND RESULTANT MIXED PCPN INCLUDING
FREEZING RAIN.
SWLY WINDS AND MILDER TEMPS WILL FOLLOW FOR MON NT INTO TUE NT.
STRONG CYCLOGENESIS IS THEN POSSIBLE VIA THE ECMWF FOR WED NT
INTO THU NT FROM THE CENTRAL GREAT PLAINS NEWD TO LAKE SUPERIOR.
THIS WOULD MAINTAIN MILD TEMPS WITH GOOD CHANCES OF RAIN...HOWEVER
STILL MENTIONED SOME SNOW AS WELL GIVEN LOWER CONFIDENCE DURING
THIS TIME.
&&
.AVIATION/00Z TAFS/...
COLD AIR ADVECTION WILL USHER PERIOD OF MVFR CIGS ACROSS TAF SITES
INTO THE EVENING. TOTAL COLUMN CONDENSATE DECREASES OVERNIGHT
HOWEVER LINGERING THERMAL TROF AND WEAK CONVERGENCE MAY RESULT IN
LOW CLOUDS PERSISTING THROUGH THE NIGHT. CONFIDENCE LOW AT THIS
POINT AND WILL MOST LIKELY BRING SOME PARTIAL CLEARING INTO TAF
SITES DURING THE NIGHT.
&&
.MARINE...
ASSUMING ICE STILL COVERS MUCH OF THE NEARSHORE WATERS WHICH WILL
CONTINUE TO REDUCE WAVE ACTION. STRONG COLD AIR ADVECTION BEHIND
CDFNT PASSING ACROSS NEARSHORE WATERS THIS EVENING WILL RESULT IN
GUSTY WINDS STRENGTHENING A BIT OVERNIGHT. POTENTIAL FOR WIND GUSTS
TO 30 KNOTS AT THE SURFACE. HENCE WL POST SMALL CRAFT ADVY FOR
OVERNIGHT HOURS.
&&
.MKX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
LM...SMALL CRAFT ADVISORY UNTIL 6 AM CST FRIDAY FOR LMZ643>646.
&&
$$
TONIGHT/FRIDAY AND AVIATION/MARINE...MBK
FRIDAY NIGHT THROUGH THURSDAY...GEHRING
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
1135 AM CST THU FEB 13 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 349 AM CST THU FEB 13 2014
AT 3 AM...A WARM FRONT WAS LOCATED ON THE EASTERN SOUTH DAKOTA
BORDER. TEMPERATURES AHEAD OF THIS FRONT RANGE FROM THE SINGLE
DIGITS TO MID 20S. MEANWHILE IN THE WAKE OF THIS FRONT...
TEMPERATURES ARE IN THE 30S AND 40S. THIS WARM FRONT HAS STRONG
FRONTOGENESIS EXTENDING FROM 900 TO 800 MB. THE RAP INDICATES THAT
THE FRONTOGENESIS WILL GRADUALLY DEEPEN UP TO 500 MB AS IT MOVES
EAST INTO WISCONSIN LATER THIS MORNING. THIS WARM FRONT IS
CURRENTLY PRODUCING SCATTERED OF SNOW IN MINNESOTA...AND THERE WAS
A REPORT OF FREEZING RAIN IN THE DES MOINES AREA. AS THIS FRONT
APPROACHES THE AREA EXPECT A BAND OF SNOW TO DEVELOP NEAR THE
INTERSTATE 35 CORRIDOR AND NORTH OF INTERSTATE 90. MEANWHILE SOUTH
OF THIS AREA...THERE WILL BE SCATTERED REPORTS OF LIGHT SNOW.
WITH MODELS INDICATING A WARM NOSE UP TO 2C BETWEEN 8 AND 9 AM
WEST OF U S HIGHWAY 52 THROUGH 9 AM...THERE MAY BE SOME PATCHY
REPORTS OF SLEET AT TIMES. OVERALL THE BEST SATURATION AND LIFT
WILL OCCUR NORTH OF INTERSTATE 94. AS A RESULT...WENT WITH THE
HIGHEST PRECIPITATION PROBABILITIES IN THESE AREAS. SNOW TOTALS OF
1 TO 2 INCHES WILL BE LIKELY ACROSS CLARK AND TAYLOR COUNTIES
TODAY.
AS A LOW PRESSURE AREA MOVES EAST ACROSS NORTHERN WISCONSIN THIS
AFTERNOON...A STRONG COLD FRONT WILL MOVE QUICKLY SOUTHEAST
ACROSS THE AREA. 850 MB TEMPERATURES DROP ANYWHERE FROM 6 TO 8C
BETWEEN 13.18Z AND 14.00Z. DUE TO THIS EXPECT...TEMPERATURES TO
SLOWLY FALL IN THE MID TO LATE AFTERNOON.
.LONG TERM...(FRIDAY THROUGH WEDNESDAY)
ISSUED AT 349 AM CST THU FEB 13 2014
ON SATURDAY...THE 13.00Z MODELS CONTINUE TO SHOW THAT A STRONG
SHORT WAVE TROUGH WILL MOVE SOUTHEAST THROUGH THE AREA. WITH THE
MODELS BEING VERY CONSISTENT IN THE LOCATION AND TIMING OF THIS
SYSTEM...INCREASED THE SNOW CHANCES UP TO 80 PERCENT ACROSS
SOUTHEAST MINNESOTA...NORTHEAST IOWA...AND SOUTHWEST WISCONSIN.
LIKE THE PAST 3 DAYS...THE BUFKIT SOUNDINGS CONTINUE TO SHOW THAT
THERE WERE BE AT LEAST A 150 MB /700 TO 550 MB/ IN THE DENDRITIC
GROWTH ZONE. THIS WILL ENHANCE THE SNOW TO LIQUID RATIOS TO AROUND
18 TO 1. WITH LIQUID PRECIPITATION AMOUNTS RANGING FROM A TENTH
TO 0.15 INCHES IN THESE AREAS...EXPECT A 2 TO 4 INCH BAND OF SNOW.
AT THIS TIME IT LOOKS LIKE IT IS CENTERED FROM AUSTIN MINNESOTA TO
OELWEIN LINE...BUT THIS LOCATION COULD DEVIATE QUITE A BIT OVER
THE NEXT SEVERAL DAYS.
ON SUNDAY NIGHT AND MONDAY...THE GFS AND ECMWF HAS FINALLY CAME TO
AN AGREEMENT THAT AN OPEN WAVE WILL MOVE QUICKLY EAST THROUGH THE
FORECAST AREA. STRONG WARM AIR ADVECTION AHEAD OF THIS SYSTEM WILL
ALLOW 850 MB TEMPERATURES TO WARM INTO THE 0 TO 4C RANGE SOUTH OF
INTERSTATE 94. AS A RESULT...EXPECT A WINTRY MIX OF FREEZING
RAIN...SLEET...AND SNOW. COBB DATA IS INDICATING A COUPLE
HUNDREDTHS OF AN INCH OF SLEET AND FREEZING RAIN MAY OCCUR NEAR
THE INTERSTATE 90 CORRIDOR...AND UP TO A TENTH OF INCH OF ICE MAY
ACCUMULATE ACROSS NORTHEAST IOWA AND SOUTHEAST MINNESOTA. NORTH OF
THE INTERSTATE 90 CORRIDOR...ANYWHERE FROM 1 TO 3 INCHES OF SNOW
WILL BE POSSIBLE. WE WILL HAVE TO CONTINUE TO WATCH THIS TIME
PERIOD CLOSELY FOR THE POTENTIAL OF A WINTER WEATHER ADVISORY.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z FRIDAY NOON)
ISSUED AT 1135 AM CST THU FEB 13 2014
SFC LOW JUST SOUTHWEST OF KDLH LATE THIS MORNING WILL CONTINUE TO
MOVE QUICKLY TOWARD NORTHERN LK MICHIGAN THRU THIS AFTERNOON/
EVENING. THIS LOW WILL DRAG A COLD FRONT THRU THE AREA...THRU KRST
AROUND 18Z AND KLSE AROUND 20Z...WITH NORTHWEST WINDS 15-25KT G30-
35KT SPREADING ACROSS THE AREA BEHIND IT FOR THE AFTERNOON. THESE
WINDS TO CREATE SOME MVFR BLSN/DRIFTING SNOW AT SITES LIKE KRST THRU
THE AFTERNOON. MVFR/IFR CLOUDS SCT -SHSN WRAPPING AROUND THE LOW
WILL SPREAD ACROSS THE TAF SITES THRU THE AFTERNOON...CLEARING KRST
LATE THIS AFTERNOON AND KLSE DURING MID EVENING AS THE LOW MOVES
EAST. WINDS DIMINISH THRU THE EVENING AS WELL WITH ANY BLSN SETTLING
DOWN AND VSBYS IMPROVING AT SITES LIKE KRST.
GENERALLY GOOD VFR EXPECTED FROM LATE EVENING THRU FRI AS THE NEXT
SYSTEM AND DEEPER MOISTURE/LIFT PASS SOUTHWEST OF THE FCST AREA.
THIS NEXT SYSTEM LOOKS TO DO LITTLE MORE THAN SPREAD SOME SCT-BKN
MID CLOUDS ACROSS THE TAF SITES ON FRI.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...BOYNE
LONG TERM....BOYNE
AVIATION.....RRS
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
555 AM CST THU FEB 13 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 349 AM CST THU FEB 13 2014
AT 3 AM...A WARM FRONT WAS LOCATED ON THE EASTERN SOUTH DAKOTA
BORDER. TEMPERATURES AHEAD OF THIS FRONT RANGE FROM THE SINGLE
DIGITS TO MID 20S. MEANWHILE IN THE WAKE OF THIS FRONT...
TEMPERATURES ARE IN THE 30S AND 40S. THIS WARM FRONT HAS STRONG
FRONTOGENESIS EXTENDING FROM 900 TO 800 MB. THE RAP INDICATES THAT
THE FRONTOGENESIS WILL GRADUALLY DEEPEN UP TO 500 MB AS IT MOVES
EAST INTO WISCONSIN LATER THIS MORNING. THIS WARM FRONT IS
CURRENTLY PRODUCING SCATTERED OF SNOW IN MINNESOTA...AND THERE WAS
A REPORT OF FREEZING RAIN IN THE DES MOINES AREA. AS THIS FRONT
APPROACHES THE AREA EXPECT A BAND OF SNOW TO DEVELOP NEAR THE
INTERSTATE 35 CORRIDOR AND NORTH OF INTERSTATE 90. MEANWHILE SOUTH
OF THIS AREA...THERE WILL BE SCATTERED REPORTS OF LIGHT SNOW.
WITH MODELS INDICATING A WARM NOSE UP TO 2C BETWEEN 8 AND 9 AM
WEST OF U S HIGHWAY 52 THROUGH 9 AM...THERE MAY BE SOME PATCHY
REPORTS OF SLEET AT TIMES. OVERALL THE BEST SATURATION AND LIFT
WILL OCCUR NORTH OF INTERSTATE 94. AS A RESULT...WENT WITH THE
HIGHEST PRECIPITATION PROBABILITIES IN THESE AREAS. SNOW TOTALS OF
1 TO 2 INCHES WILL BE LIKELY ACROSS CLARK AND TAYLOR COUNTIES
TODAY.
AS A LOW PRESSURE AREA MOVES EAST ACROSS NORTHERN WISCONSIN THIS
AFTERNOON...A STRONG COLD FRONT WILL MOVE QUICKLY SOUTHEAST
ACROSS THE AREA. 850 MB TEMPERATURES DROP ANYWHERE FROM 6 TO 8C
BETWEEN 13.18Z AND 14.00Z. DUE TO THIS EXPECT...TEMPERATURES TO
SLOWLY FALL IN THE MID TO LATE AFTERNOON.
.LONG TERM...(FRIDAY THROUGH WEDNESDAY)
ISSUED AT 349 AM CST THU FEB 13 2014
ON SATURDAY...THE 13.00Z MODELS CONTINUE TO SHOW THAT A STRONG
SHORT WAVE TROUGH WILL MOVE SOUTHEAST THROUGH THE AREA. WITH THE
MODELS BEING VERY CONSISTENT IN THE LOCATION AND TIMING OF THIS
SYSTEM...INCREASED THE SNOW CHANCES UP TO 80 PERCENT ACROSS
SOUTHEAST MINNESOTA...NORTHEAST IOWA...AND SOUTHWEST WISCONSIN.
LIKE THE PAST 3 DAYS...THE BUFKIT SOUNDINGS CONTINUE TO SHOW THAT
THERE WERE BE AT LEAST A 150 MB /700 TO 550 MB/ IN THE DENDRITIC
GROWTH ZONE. THIS WILL ENHANCE THE SNOW TO LIQUID RATIOS TO AROUND
18 TO 1. WITH LIQUID PRECIPITATION AMOUNTS RANGING FROM A TENTH
TO 0.15 INCHES IN THESE AREAS...EXPECT A 2 TO 4 INCH BAND OF SNOW.
AT THIS TIME IT LOOKS LIKE IT IS CENTERED FROM AUSTIN MINNESOTA TO
OELWEIN LINE...BUT THIS LOCATION COULD DEVIATE QUITE A BIT OVER
THE NEXT SEVERAL DAYS.
ON SUNDAY NIGHT AND MONDAY...THE GFS AND ECMWF HAS FINALLY CAME TO
AN AGREEMENT THAT AN OPEN WAVE WILL MOVE QUICKLY EAST THROUGH THE
FORECAST AREA. STRONG WARM AIR ADVECTION AHEAD OF THIS SYSTEM WILL
ALLOW 850 MB TEMPERATURES TO WARM INTO THE 0 TO 4C RANGE SOUTH OF
INTERSTATE 94. AS A RESULT...EXPECT A WINTRY MIX OF FREEZING
RAIN...SLEET...AND SNOW. COBB DATA IS INDICATING A COUPLE
HUNDREDTHS OF AN INCH OF SLEET AND FREEZING RAIN MAY OCCUR NEAR
THE INTERSTATE 90 CORRIDOR...AND UP TO A TENTH OF INCH OF ICE MAY
ACCUMULATE ACROSS NORTHEAST IOWA AND SOUTHEAST MINNESOTA. NORTH OF
THE INTERSTATE 90 CORRIDOR...ANYWHERE FROM 1 TO 3 INCHES OF SNOW
WILL BE POSSIBLE. WE WILL HAVE TO CONTINUE TO WATCH THIS TIME
PERIOD CLOSELY FOR THE POTENTIAL OF A WINTER WEATHER ADVISORY.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z FRIDAY MORNING)
ISSUED AT 555 AM CST THU FEB 13 2014
THE MAIN WEATHER CONCERNS THROUGH TOMORROW MORNING ARE WITH THE
SNOW THIS MORNING TO GO ALONG WITH THE GUSTY WINDS. A BAND OF SNOW
IS MOVING EAST ACROSS THE REGION WITH VISIBILITY DROPPING DOWN TO
AROUND 2SM WHEN THE SNOW FALLS. THE BACK EDGE OF IT IS ALONG A
WARM FRONT THAT IS JUST WEST OF RST RIGHT NOW. OVER THE NEXT FEW
HOURS...THE SNOW WILL COME TO AN END AND THE WARM FRONT WILL COME
THROUGH AND BRING WINDS AROUND TO THE SOUTHWEST AND BECOME FAIRLY
GUSTY AT 25 TO 30KTS. CONDITIONS MAY GO VFR FOR A PERIOD THIS
MORNING...THOUGH SOME BLOWING/DRIFTING SNOW COULD KEEP VIS DOWN
INTO THE MVFR RANGE AT RST. A COLD FRONT WILL SWING THROUGH LATER
THIS MORNING AND BRING WINDS AROUND TO THE NORTHWEST AND REMAIN
GUSTY THROUGH THE REST OF THE AFTERNOON. WINDS WILL GRADUALLY
SUBSIDE AND SKIES SHOULD CLEAR OUT THIS EVENING AS THE SYSTEM
TRACKS TO THE EAST.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...BOYNE
LONG TERM...BOYNE
AVIATION...HALBACH
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
350 AM CST THU FEB 13 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 349 AM CST THU FEB 13 2014
AT 3 AM...A WARM FRONT WAS LOCATED ON THE EASTERN SOUTH DAKOTA
BORDER. TEMPERATURES AHEAD OF THIS FRONT RANGE FROM THE SINGLE
DIGITS TO MID 20S. MEANWHILE IN THE WAKE OF THIS FRONT...
TEMPERATURES ARE IN THE 30S AND 40S. THIS WARM FRONT HAS STRONG
FRONTOGENESIS EXTENDING FROM 900 TO 800 MB. THE RAP INDICATES THAT
THE FRONTOGENESIS WILL GRADUALLY DEEPEN UP TO 500 MB AS IT MOVES
EAST INTO WISCONSIN LATER THIS MORNING. THIS WARM FRONT IS
CURRENTLY PRODUCING SCATTERED OF SNOW IN MINNESOTA...AND THERE WAS
A REPORT OF FREEZING RAIN IN THE DES MOINES AREA. AS THIS FRONT
APPROACHES THE AREA EXPECT A BAND OF SNOW TO DEVELOP NEAR THE
INTERSTATE 35 CORRIDOR AND NORTH OF INTERSTATE 90. MEANWHILE SOUTH
OF THIS AREA...THERE WILL BE SCATTERED REPORTS OF LIGHT SNOW.
WITH MODELS INDICATING A WARM NOSE UP TO 2C BETWEEN 8 AND 9 AM
WEST OF U S HIGHWAY 52 THROUGH 9 AM...THERE MAY BE SOME PATCHY
REPORTS OF SLEET AT TIMES. OVERALL THE BEST SATURATION AND LIFT
WILL OCCUR NORTH OF INTERSTATE 94. AS A RESULT...WENT WITH THE
HIGHEST PRECIPITATION PROBABILITIES IN THESE AREAS. SNOW TOTALS OF
1 TO 2 INCHES WILL BE LIKELY ACROSS CLARK AND TAYLOR COUNTIES
TODAY.
AS A LOW PRESSURE AREA MOVES EAST ACROSS NORTHERN WISCONSIN THIS
AFTERNOON...A STRONG COLD FRONT WILL MOVE QUICKLY SOUTHEAST
ACROSS THE AREA. 850 MB TEMPERATURES DROP ANYWHERE FROM 6 TO 8C
BETWEEN 13.18Z AND 14.00Z. DUE TO THIS EXPECT...TEMPERATURES TO
SLOWLY FALL IN THE MID TO LATE AFTERNOON.
.LONG TERM...(FRIDAY THROUGH WEDNESDAY)
ISSUED AT 349 AM CST THU FEB 13 2014
ON SATURDAY...THE 13.00Z MODELS CONTINUE TO SHOW THAT A STRONG
SHORT WAVE TROUGH WILL MOVE SOUTHEAST THROUGH THE AREA. WITH THE
MODELS BEING VERY CONSISTENT IN THE LOCATION AND TIMING OF THIS
SYSTEM...INCREASED THE SNOW CHANCES UP TO 80 PERCENT ACROSS
SOUTHEAST MINNESOTA...NORTHEAST IOWA...AND SOUTHWEST WISCONSIN.
LIKE THE PAST 3 DAYS...THE BUFKIT SOUNDINGS CONTINUE TO SHOW THAT
THERE WERE BE AT LEAST A 150 MB /700 TO 550 MB/ IN THE DENDRITIC
GROWTH ZONE. THIS WILL ENHANCE THE SNOW TO LIQUID RATIOS TO AROUND
18 TO 1. WITH LIQUID PRECIPITATION AMOUNTS RANGING FROM A TENTH
TO 0.15 INCHES IN THESE AREAS...EXPECT A 2 TO 4 INCH BAND OF SNOW.
AT THIS TIME IT LOOKS LIKE IT IS CENTERED FROM AUSTIN MINNESOTA TO
OELWEIN LINE...BUT THIS LOCATION COULD DEVIATE QUITE A BIT OVER
THE NEXT SEVERAL DAYS.
ON SUNDAY NIGHT AND MONDAY...THE GFS AND ECMWF HAS FINALLY CAME TO
AN AGREEMENT THAT AN OPEN WAVE WILL MOVE QUICKLY EAST THROUGH THE
FORECAST AREA. STRONG WARM AIR ADVECTION AHEAD OF THIS SYSTEM WILL
ALLOW 850 MB TEMPERATURES TO WARM INTO THE 0 TO 4C RANGE SOUTH OF
INTERSTATE 94. AS A RESULT...EXPECT A WINTRY MIX OF FREEZING
RAIN...SLEET...AND SNOW. COBB DATA IS INDICATING A COUPLE
HUNDREDTHS OF AN INCH OF SLEET AND FREEZING RAIN MAY OCCUR NEAR
THE INTERSTATE 90 CORRIDOR...AND UP TO A TENTH OF INCH OF ICE MAY
ACCUMULATE ACROSS NORTHEAST IOWA AND SOUTHEAST MINNESOTA. NORTH OF
THE INTERSTATE 90 CORRIDOR...ANYWHERE FROM 1 TO 3 INCHES OF SNOW
WILL BE POSSIBLE. WE WILL HAVE TO CONTINUE TO WATCH THIS TIME
PERIOD CLOSELY FOR THE POTENTIAL OF A WINTER WEATHER ADVISORY.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z THURSDAY EVENING)
ISSUED AT 1100 PM CST WED FEB 12 2014
STRATUS DECK TO THE WEST HAS BEEN FAIRLY STUBBORN SITTING
THERE...WITH LITTLE IF ANY MOVEMENT EAST. MESO MODELS STILL SUGGEST
THIS WILL EVENTUALLY CREEP EAST...WITH SOME LOW STRATUS TO THE SOUTH
POSSIBLY REACHING KLSE BEFORE IT DOES. WILL CONTINUE TO PLAY MVFR
CIGS FOR KRST/KLSE...BUT WILL MOVE BACK THE TIMING.
AN UPPER LEVEL SHORTWAVE IS DRIVING -SN PRODUCTION ACROSS ND/WESTERN
MN...WITH RAP13/NAM12 SUGGESTING THE BULK OF THE ACCUMULATING SNOWS
HOLDING WELL NORTH OF THE TAF SITES...MOSTLY NORTH OF I-94. SOME
CONVECTIVE ELEMENTS ALONG THE SOUTHERN FLANK...ON THE LEADING EDGE
OF THE SHORTWAVE. NOT MUCH GROUND TRUTH EVIDENCE VIA OBS YET. WILL
STAY WITH A SHORT PERIOD OF -SN FOR KLSE/KRST...BUT KEEP VSBY
RESTRICTIONS CONFINED TO KLSE FOR THE MOMENT. ANY ACCUMULATION WOULD
STAY UNDER 1/2 INCH.
MODELED LOW LEVEL RH HOLDS ONTO SATURATION THROUGH THE DAY...BUT
BUFKIT SOUNDINGS SUGGEST A BREAK UP IN THE CIGS IS POSSIBLE THU
AFTERNOON. GOING TO HOLD WITH SOME BKN FOR NOW...BUT WILL MOVE TO
VFR.
WINDS ARE GOING TO BE ON THE INCREASE BY 12Z THU...REMAINING
BLUSTERY/GUSTY FROM THE SOUTH FOR THE BETTER PART OF THE DAY. COLD
FRONT WILL SWEEP IN FOR THE AFTERNOON...SWINGING WINDS TO THE
WEST/NORTHWEST. PRESSURE GRADIENT STAYS FAIRLY TIGHT FOR THE BETTER
PART OF THU NIGHT. IN ADDITION...SEE A FEW HOUR WINDOW EARLY THU
MORNING FOR LLWS AT KRST/KLSE. BORDER LINE AT THE MOMENT...SO WON/T
INCLUDE IN THE TAFS.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...BOYNE
LONG TERM...BOYNE
AVIATION.....RIECK
AREA FORECAST DISCUSSION
NWS MOUNT HOLLY NJ
408 AM EST SAT FEB 15 2014
.SYNOPSIS...
THE LATEST LOW PRESSURE SYSTEM WILL QUICKLY SLIDE EAST OFF THE COAST
TODAY...BUT NOT BEFORE IT BRINGS ANOTHER ROUND OF SNOW TO THE
REGION. HIGH PRESSURE WILL THEN BE THE DOMINANT FEATURE IN THE
REGIONAL WEATHER PATTERN THROUGH MONDAY...FOLLOWED BY FAST MOVING
BUT RELATIVELY WEAK FRONTAL SYSTEMS ON TUESDAY AND WEDNESDAY. A
STRONGER WARM FRONT AND ASSOCIATED LOW PRESSURE WILL AFFECT THE AREA
THURSDAY NIGHT INTO FRIDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
AN AREA OF LOW PRESSURE WILL MOVE ACRS NC THIS MRNG THEN NEWD OFF
THE ATLC CST. IT WILL RAPIDLY INTENSIFY WELL OFF THE CST AS IT
MOVS TWD THE CANADIAN MARITIMES BY SUN MRNG. AS THE LOW MOVES ON
BY, IT WILL BRING SOME PRECIP WITH IT.
LATEST RADAR SHOWED SOME SNOW ACRS WRN SECTIONS OF THE AREA ALREADY
THIS MRNG WITH BOTH KRDG AND KABE REPORTING SNOW. THE GUID IS
HAVING SOME DISAGREEMENT AS TO HOW FAST IT PUSHES EAST, WITH MOST IN
AGREEMENT THAT IT DOESN`T GET TO THE I-95 CORRIDOR UNTIL AT LEAST
AROUND DAYBREAK.
THERE ARE ALSO SOME QUESTIONS AS TO HOW MUCH QPF WE WILL SEE, WITH
THE HRRR AND ECMWF ON THE LOWER END AND THE SREF AND GFS A BIT
HIGHER. FROM THE I-95 CORRIDOR S AND E, THERE IS ALSO THE QUESTION
OF TEMPS AND PRECIP TYPE AS TEMPS ARE FCST TO GET ABV FREEZING DURG
THE DAY SO THERE SHOULD AT LEAST BE SOME MIXING AND CHANGING DURG
THE DAY TODAY.
THEREFORE, WILL BE KEEPING ACCUMS ABOUT THE SAME AND NOT BE MAKING
ANY CHANGES TO THE ADVYS. HOWEVER, IT SEEMS THAT THIS WINTER
VIRTUALLY EVERY SYS HAS OVERPERFORMED, SO IF THIS ONE DOES, THERE
MAY NEED TO BE A SEWD MVMT OF ADVYS, BUT CERTAINLY THIS IS A MORE
MARGINAL EVENT DUE TO TIME OF YEAR, TIME OF DAY AND TEMPS.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 AM SUNDAY/...
PRECIP SHOULD BE ALL BUT OVER OR COMING TO AN END AT THE START OF
THE PD AND HIGH PRES WILL BUILD IN FROM THE W. THE PGRAD BETWEEN
THE AFOREMENTIONED HIGH AND THE INTENSIFYING LOW WILL BE QUITE
STRONG AND EXPECT GUSTY NW WIND TO DEVELOP. THIS WILL MAKE A COLD
NIGHT FEEL EVEN COLDER. WIND COULD GUST UPWARDS OF 25 TO 30 MPH AND
THE SKY WILL GRADUALLY CLEAR.
&&
.LONG TERM /SUNDAY THROUGH FRIDAY/...
IN THE WAKE OF TODAY`S LOW...HIGH PRESSURE AT THE SURFACE AND
RIDGING ALOFT WILL START TO BUILD IN. THERE IS ONE EXCEPTION ON
SUNDAY AFTERNOON...BOTH THE GFS AND NAM SHOW WEAK POSITIVE PRESSURE
ADVECTION AT THE 1.5PV LEVEL ACROSS E CENTRAL PA INTO NW NJ. THIS
LOOKS TO BE ASSOCIATED WITH A SMALL EMBEDDED UPPER LEVEL TROUGH. THE
WINDOW OF LIFT IS LIMITED TO JUST A FEW HOURS SUNDAY AFTERNOON...AND
WITH NORTHERLY FLOW...THERE IS LIMITED MOISTURE. STILL THERE IS A
BRIEF WINDOW OF OPPORTUNITY FOR SOME SNOW. DUE TO THE BRIEF WINDOW
OF OPPORTUNITY...DO NOT ANTICIPATE MUCH ADDITIONAL ACCUMULATION AT
THIS TIME.
THE CONTINENTAL POLAR AIR MASS REMAINS IN PLACE THROUGH AT LEAST
MONDAY...LIMITING...AT LEAST FOR NOW...SIGNIFICANT MELTING OF THE
SNOWPACK OVER THE REGION. CONSIDERING THIS...HAVE FOLLOWED THE
TREND OF PREVIOUS SHIFTS IN UNDERCUTTING GUIDANCE FOR MAX
TEMPERATURES DUE TO THE SNOWPACK FOR MOST OF THE REGION.
THE FIRST SIGN OF THE WARMER PATTERN SHIFT COMES WITH THE SYSTEM
MONDAY NIGHT INTO TUESDAY. THOUGH ANY PRECIPITATION WITH THIS
SYSTEM SHOULD INITIALLY BEGIN AS SNOW...A WEAK WARM FRONT SHOULD
LIFT AS FAR NORTH AS THE DELMARVA AREA...SO AT LEAST THE SOUTHERN
HALF OF OUR REGION MAY SEE A BRIEF CHANGE OVER TO RAIN BEFORE THE
PRECIPITATION ENDS TUESDAY AFTERNOON.
THEN COMES THE REALLY EXCITING PART OF THE FORECAST...WE SHOULD
SEE A PAIR OF WARM FRONTS...ONE ON WEDNESDAY...ANOTHER ONE
THURSDAY...BRINGING WARMER CONDITIONS TO THE REGION. IN BOTH
CASES...MOST OF THE PRECIPITATION WE EXPECT WITH THESE SYSTEMS
SHOULD BE IN THE WARM SECTOR...MEANING WE WOULD EXPECT TO SEE
MOSTLY RAIN. GIVEN THE HIGH LIQUID CONTENT OF THE SNOW
PACK...STILL UNDERCUT GUIDANCE MAX T FOR THE DELAWARE RIVER VALLEY
AND LOCATIONS NORTHWEST OF THERE ON WEDNESDAY...AND UNDERCUT
GUIDANCE IN THE POCONOS AND THE LEHIGH VALLEY...WHERE CURRENT SNOW
DEPTHS ARE ABOVE 20 INCHES...THROUGH THE END OF THE WEEK.
&&
.AVIATION /09Z SATURDAY THROUGH WEDNESDAY/...
LTST RADAR IMAGERY SHOWED A BAND OF SNOW OVER THE NRN AND WRN
AREAS. THIS SNOW DROPPED KRDG DOWN FAIRLY QUICKLY AS IT MOVED BY
BUT THEY HAVE RETURNED TO VFR CIGS BUT MVFR VSBY NOW THAT IT HAS
PASSED. KABE REMAINS MVFR AND SOME IFR IS NOT OUT OF THE QUESTION
UNTIL IT MOVES BY THEM. ALL OTHER SITES REMAIN VFR. IT IS EXPECTED
THEY WILL REMAIN VFR UNTIL IMPACTED BY PRECIP LATER THIS MRNG. ALG
THE I-95 CORRIDOR, THAT SHUD BE AROUND DAYBREAK.
THE LATEST GUID INDICATES THAT ONCE A SITE GOES DOWN THEY SHUD STAY
DOWN, BUT BASED UPON WHAT IS BEING OBSERVED SO FAR TONIGHT,
CONFIDENCE IS LOW ON THAT. THERE WILL CERTAINLY BE PERIODS OF
REDUCED CIGS/VSBYS BUT ITS PSBL THERE COULD BE SOME BREAKS AS WELL.
FROM THE I-95 CORRIDOR S AND E PRECIP COULD MIX WITH OR CHANGE TO
RAIN AS WELL DURING THE DAY AS TEMPS CLIMB ABV FREEZING.
BY EVENING, MOST IF NOT ALL OF THE PRECIP IS OVER AND CONDS SHUD
RETURN TO VFR. THEN THE NEXT ISSUE IS A STRONG AND GUSTY NW WIND
WHICH WILL DEVELOP THE WIND CUD GUST TO 30 KTS OVERNIGHT.
OUTLOOK...
SUNDAY...GENERALLY VFR. A FEW LIGHT SHSN WILL BE POSSIBLE MAINLY
NW OF KABE.
MONDAY...GENERALLY VFR THROUGH THE DAY.
MONDAY NIGHT AND TUESDAY...MVFR AND OCCASIONAL IFR IN SN THROUGH
TUESDAY MORNING. PRECIPITATION MAY BRIEFLY CHANGE TO RA IN THE
AFTERNOON BEFORE ENDING...WITH A RETURN TO VFR CONDITIONS.
WEDNESDAY...GENERALLY VFR WITH SOME MVFR CEILINGS POSSIBLE IN RA
DURING THE DAY WEDNESDAY.
&&
.MARINE...
AN AREA OF LOW PRESSURE WILL MOVE ACRS NC THIS MRNG THEN OFF THE
ATLC CST AS IT MOVES NEWD TWD THE CAN MARITIMES BY SUN MRNG. THE
LOW WILL RAPIDLY INTENSIFY AS IT MOVES TWD CANADA. THE PRESSURE
GRADIENT BETWEEN THIS LOW AND HIGH PRESSURE THAT MOVES IN BEHIND IT
WILL BECOME QUITE STRONG AND A GUSTY NW WIND IS EXPECTED TO DEVELOP
BY LATE AFTN. THEREFORE, THE GALE WATCH IS BEING REPLACED BY A GALE
WRNG FOR ALL MARINE ZONES AND IT WILL BE IN EFFECT THRU 11Z.
OUTLOOK...
SUNDAY...SCA CONDITIONS EXPECTED FOR MUCH OF THE DAY...DECREASING
BELOW SCA BY LATE SUNDAY NIGHT.
MONDAY THROUGH WEDNESDAY...SUB-SCA CONDITIONS EXPECTED.
&&
.PHI WATCHES/WARNINGS/ADVISORIES...
PA...WINTER WEATHER ADVISORY UNTIL 6 PM EST THIS EVENING FOR PAZ054-
055-060>062-101>106.
NJ...WINTER WEATHER ADVISORY UNTIL 6 PM EST THIS EVENING FOR NJZ001-
007>009.
DE...NONE.
MD...WINTER WEATHER ADVISORY UNTIL 6 PM EST THIS EVENING FOR MDZ008.
MARINE...GALE WARNING FROM 4 PM THIS AFTERNOON TO 6 AM EST SUNDAY FOR
ANZ430-431-450>455.
&&
$$
SYNOPSIS...JOHNSON
NEAR TERM...NIERENBERG
SHORT TERM...NIERENBERG
LONG TERM...JOHNSON
AVIATION...JOHNSON/NIERENBERG
MARINE...JOHNSON/NIERENBERG
AREA FORECAST DISCUSSION
NWS COLUMBIA SC
151 AM EST SAT FEB 15 2014
.SYNOPSIS...
A FRONT WILL CROSS THE REGION LATE TONIGHT...WHICH WILL BRING A
PERIOD OF SHOWERS FOLLOWED BY WINDY CONDITIONS SATURDAY. FAIR
WEATHER EXPECTED SUNDAY AND MONDAY. A WEAK FRONT WILL APPROACH THE
REGION TUESDAY. A WARMING TREND IS EXPECTED NEXT WEEK.
&&
.NEAR TERM /THROUGH TODAY/...
STRONG SHORT WAVE TROUGH OVER WEST GEORGIA AT 06Z. COLD FRONT
ASSOCIATED WITH FAST MOVING/CLIPPER TYPE SYSTEM APPROACHING THE
REGION FROM THE WEST EARLY THIS MORNING. STRONG HEIGHT
FALLS COMBINED WITH THE FORECAST AREA FALLING WITHIN THE FAVORED
LEFT EXIT REGION OF THE UPPER JET WILL BRING STRONG UPWARD
VERTICAL MOTION OVER THE AREA DURING THE 06Z-12Z TIME FRAME.
LATEST REGIONAL RADAR SHOWING RAIN MOVING ACROSS
CSRA/PIEDMONT...WILL SPREAD ACROSS MIDLANDS MAINLY BEFORE DAWN.
CATEGORICAL POPS BEFORE 12Z. CONFIDENCE IS HIGH MEASURABLE
PRECIPITATION WILL BE OBSERVED...ALTHOUGH OVERALL PRECIPITATION
AMOUNTS WILL BE LIMITED BY INITIAL DRY AIR IN PLACE AND THE SPEED
OF THIS SYSTEM. GENERALLY EXPECTING AROUND A TENTH TO UP TO 0.25
INCHES OF RAINFALL. LATEST MESOSCALE MODELS SUGGEST RAIN WILL
EXIT REGION BEFORE 15Z AT THE LATEST. SO CUT POPS BACK AFTER
12Z...WITH DECREASING CLOUDS AS LOW PRESSURE SYSTEM MOVES OFF TO
THE NORTHEAST.
SOME WEAK COLD ADVECTION EXPECTED ON SATURDAY BUT WITH CLEARING
SKIES AND PLENTY OF SUN TEMPERATURES WILL ONLY BE A CATEGORY OR SO
COOLER THAN TODAY. THE WINDS WILL BE THE MAIN FOCUS ON SATURDAY
WITH A TIGHT PRESSURE GRADIENT BETWEEN THE DEEPENING LOW OFFSHORE
AND HIGH PRESSURE BUILDING IN FROM THE WEST. LAKE WIND ADVISORY
FROM 7 AM THROUGH 5 PM TO ACCOUNT FOR THE STRONG WINDS. THE
POTENTIAL FOR A WIND ADVISORY EXISTS AS THE UPPER SYSTEM BECOMES A
BIT NEGATIVELY TILTED AND THERE WILL BE SOME DOWNSLOPING FLOW.
LATEST LAMP AND RAP GUIDANCE SUGGESTS WINDS GUSTS AROUND 30 KTS...SO
WILL HOLD OFF ON WIND ADVISORY.
THE SIGNIFICANT WINDS ON SATURDAY MAY IMPEDE THE ICE STORM CLEAN
UP IN THE SOUTHERN MIDLANDS AND CENTRAL SAVANNAH RIVER AREA. HIGH
TEMPERATURES SHOULD RANGE FROM THE UPPER 40S TO AROUND 50 NORTHERN
MIDLANDS TO MID 50S SOUTHEASTERN MIDLANDS.
&&
.SHORT TERM /TONIGHT THROUGH MONDAY/...
SOME CLOUDS LATE TONIGHT AND EARLY SUNDAY ASSOCIATED WITH WEAK
TROUGH BUT AIR MASS WILL BE DRY. GUIDANCE TEMPERATURES MAINLY IN
THE MID TO UPPER 20S...MAY BE TOO LOW DUE TO CLOUDS. TEMPERATURES MODERATING
ON SUNDAY WITH HIGH PRESSURE ACROSS THE AREA AND DOWNSLOPE FLOW.
MAX TEMPERATURES IN THE LOW TO MID 50S NORTH TO THE LOW 60S CSRA.
&&
.LONG TERM /MONDAY NIGHT THROUGH FRIDAY/...
UPPER LEVEL FLOW WILL BECOME ZONAL THROUGH MID WEEK...WITH UPPER
GROGGINESS DEVELOPING TO OUR WEST BY LATE WEEK. A FRONT WILL
APPROACH THE REGION TUESDAY...THEN STALL AND LIFT NORTH AS A WARM
FRONT THROUGH LATE WEEK...PROVIDING A SLIGHT CHANCE OF SHOWERS.
UPPER HEIGHT RISES OVER THE SE CONUS...AND S TO SW LOW LEVEL FLOW
AHEAD OF ANOTHER APPROACHING FRONT...WILL PROVIDE WARM
TEMPERATURES MID TO LATE WEEK.
&&
.AVIATION /07Z SATURDAY THROUGH WEDNESDAY/...
MVFR CONDITIONS MOVING INTO THE TAF SITES...WITH IMPROVING
CONDITIONS AFTER 12Z.
FAST MOVING SYSTEM CURRENTLY JUST WEST OF THE TAF SITES WILL
SPREAD MVFR AND RAIN SHOWERS INTO THE TAF SITES BY 07Z...08Z IN
OGB. SYSTEM WILL BE EXITING EASTWARD AROUND 12Z WITH CONDITIONS
IMPROVING TO VFR. MAIN CONCERN THROUGH THE PERIOD WILL BE WINDS
WHICH WILL BECOME SOUTHWESTERLY AROUND 10 KNOTS WITH GUSTS TO 17
KNOTS AS THE RAIN MOVES INTO THE AREA...THEN FURTHER INCREASE
WESTERLY TO AROUND 18 KNOTS WITH GUSTS TO 27 KNOTS AROUND 12Z AS
THE PRESSURE GRADIENT TIGHTENS ON THE BACKSIDE OF THE SYSTEM.
WINDS WILL SLOWLY BEGIN TO SUBSIDE DURING THE AFTERNOON AND
EVENING HOURS...BECOMING LIGHT AND VARIABLE BY 16/02Z.
EXTENDED AVIATION OUTLOOK...NO SIGNIFICANT IMPACTS TO AVIATION
EXPECTED SUNDAY MORNING THROUGH WEDNESDAY.
&&
.CAE WATCHES/WARNINGS/ADVISORIES...
SC...LAKE WIND ADVISORY FROM 7 AM THIS MORNING TO 5 PM EST THIS
AFTERNOON FOR SCZ015-016-018-020>022-025>031-035>038-041.
GA...LAKE WIND ADVISORY FROM 7 AM THIS MORNING TO 5 PM EST THIS
AFTERNOON FOR GAZ040-063>065-077.
&&
$$
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
326 AM CST Sat Feb 15 2014
...Update for the long term discussion...
.SHORT TERM...(Today and tonight)
ISSUED AT 123 AM CST SAT FEB 15 2014
Today:
Pretty interesting temperature forecast for today. A lee low with an
associated warm front will clip the southern part of the forecast area
of responsibility during the afternoon. Here, very warm 850 hPa temperatures
of 18-20C & downslope plume will be pretty close to the Colorado and
Oklahoma state borders. The tail end of the HRRR is also latching on
to this in the reflection of a sfc thermal gradient across far southwest
Kansas. Think that mid 70sF will be a distinct possibility by Elkhart.
Elsewhere, an approaching cold front will move across portions of southwest
Kansas today. As seen with yesterday, there will be considerable mixing
and think that the NAM is under-doing this and the low level thermal
gradient. Will call for a gradient of low 60sF across much of the forecast
area with mid 60sF to low 70sF across far western Kansas.
Tonight:
By this evening, high pressure will ridge across the outlook area with
fairly light winds. There will be weak upslope flow across western
Kansas with weak warm air advection in the low levels on the backside
of the departing high. The NAM/NSSL WRF/SREF probabilities show fog
potential for Sunday morning. Not very confident in spatial arrangement
of fog, but have added it in the wx grids in case these three models
are correct. Future shifts can adjust as necessary. Dewpoints won`t
be very high, but there could be a radiational fog environment with
an inversion and light sfc winds. Overnight minimums will be higher
as fog and mid to high level cloud cover lingers. Saw no reason to deviate
from previous forecast, which is widespread low 30s for lows.
.LONG TERM...(Sunday through Friday)
ISSUED AT 314 AM CST SAT FEB 15 2014
On Sunday, there will be a nearly zonal flow over the plains, with a
cold front approaching from the north. It should be mostly sunny
with mainly high cirrus clouds passing overhead. Winds will be from
the southwest and the pressure gradient will tighten up in the
afternoon as the cold front encroaches. Winds should start out
from the southwest at 5 to 15 mph in the morning, but increase
from the southwest at 15 to 20 mph with gusts to near 30 mph in
the afternoon. It should warm up nicely into the upper 50s to
lower 60s, but the winds will still be noticeable. Sunday night
could be windier than Sunday, as the cold front moves through.
South winds will shift to the northwest at 15 to 30 mph, gusting
as high as 40 mph. A wind advisory may be needed for parts of
Sunday night and Monday morning. Those strong winds will continue
into Monday morning, bringing the same 20 mph to 30 mph gusting to
40 mph range to that area east of a Scott City to Meade line. By
late Monday, winds should be from the west at around 10 mph. The
cold front will bring down max temps somewhat, into the middle
50s.
Tuesday will respond to a wind shift back to the southwest, with
mostly sunny skies and maximum temperatures in the middle to upper 60s.
A zonal flow will return aloft Tuesday into Wednesday. Wednesday
should be the warmest day overall, with lower 60s expected north of
I-70, and maxes around 70F along the Oklahoma border. A large upper
level trough will approach from the west Wednesday night, bringing
first a slight chance for rain to our western CWA, basically west of
a Hays to Liberal line, and then a chance for light snow after
midnight Wednesday night. By Thursday morning, there will be a cold
front dragging through southwest Kansas, the precip may be either
rain or snow Thursday morning. By afternoon, the lower layers
should warm up enough to change any precipitation back to rain,
east of a Scott City to Garden City to near Liberal line. Right
now, I do not think anyone will get more than light rain or light
snow.
We will go into a zonal flow aloft by Friday, and then to a
southwest upper level flow by Saturday. Friday will be a moderating
day with highs in the mid 50s to lower 60s, then clouds and shallow
cold air spilling south from the northern plains will dip maximum temperatures
back into the lower to middle 40s by Saturday, which will be closer
to climatological highs.
&&
.AVIATION...(For the 06Z TAFS through 06Z Saturday night)
ISSUED AT 1100 PM CST FRI FEB 14 2014
Some mid to high level clouds this morning/today. Frontal system moves
through with southerly winds veering northwesterly by noon or so then
northerly this afternoon. Magnitudes 10-15 kt.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 62 31 61 39 / 0 0 0 0
GCK 63 32 62 39 / 0 0 0 0
EHA 76 32 69 41 / 0 0 0 0
LBL 69 32 66 41 / 0 0 0 0
HYS 61 30 57 36 / 0 0 0 0
P28 61 32 59 40 / 0 0 0 0
&&
.DDC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...Sugden
LONG TERM...Burke
AVIATION...Sugden
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
123 AM CST Sat Feb 15 2014
...Update to short term...
.SHORT TERM...(Today and tonight)
ISSUED AT 123 AM CST SAT FEB 15 2014
Today:
Pretty interesting temperature forecast for today. A lee low with an
associated warm front will clip the southern part of the forecast area
of responsibility during the afternoon. Here, very warm 850 hPa temperatures
of 18-20C & downslope plume will be pretty close to the Colorado and
Oklahoma state borders. The tail end of the HRRR is also latching on
to this in the reflection of a sfc thermal gradient across far southwest
Kansas. Think that mid 70sF will be a distinct possibility by Elkhart.
Elsewhere, an approaching cold front will move across portions of southwest
Kansas today. As seen with yesterday, there will be considerable mixing
and think that the NAM is under-doing this and the low level thermal
gradient. Will call for a gradient of low 60sF across much of the forecast
area with mid 60sF to low 70sF across far western Kansas.
Tonight:
By this evening, high pressure will ridge across the outlook area with
fairly light winds. There will be weak upslope flow across western
Kansas with weak warm air advection in the low levels on the backside
of the departing high. The NAM/NSSL WRF/SREF probabilities show fog
potential for Sunday morning. Not very confident in spatial arrangement
of fog, but have added it in the wx grids in case these three models
are correct. Future shifts can adjust as necessary. Dewpoints won`t
be very high, but there could be a radiational fog environment with
an inversion and light sfc winds. Overnight minimums will be higher
as fog and mid to high level cloud cover lingers. Saw no reason to deviate
from previous forecast, which is widespread lows 30sF for lows.
.LONG TERM...(Saturday night through Friday)
ISSUED AT 204 PM CST FRI FEB 14 2014
The mid to high level flow will remain mostly zonal through Tuesday,
with a progressive shortwave trough passing by Monday morning.
Mild weather can be expected Sunday ahead of the associated front
with highs in the 50s/60s; then Monday should be just a little
cooler with highs in the 50s.
After a mild day Tuesday with highs in the 60s to lower 70s, along
with weak lee troughing on the high plains, a longwave upper level
trough is expected to develop over the high plains and Rockies by
mid to late week, with strong, embedded shortwave troughs and
associated cold fronts progressing across the plains. The timing
and amplitude of these systems late Wednesday/Thursday and then
again late Friday or early Saturday is questionable. But all the
models suggest a rather progressive series of shortwave troughs,
with most of the low level moisture well off to the east. There
may be enough mid level moisture for a few showers or a little
light snow late Wednesday night into Thursday, with high
temperatures cooling back into the high 40s or lower 50s on
Thursday, depending on the extent of cloud and precipitation. At
this point, we are not expecting any major precipitation events
through February 24th.
&&
.AVIATION...(For the 06Z TAFS through 06Z Saturday night)
ISSUED AT 1100 PM CST FRI FEB 14 2014
Some mid to high level clouds this morning/today. Frontal system moves
through with southerly winds veering northwesterly by noon or so then
northerly this afternoon. Magnitudes 10-15 kt.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 62 32 61 39 / 0 0 0 0
GCK 63 33 62 39 / 0 0 0 0
EHA 76 35 69 41 / 0 0 0 0
LBL 69 34 66 41 / 0 0 0 0
HYS 61 31 57 36 / 0 0 0 0
P28 61 33 59 40 / 0 0 0 0
&&
.DDC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...Sugden
LONG TERM...Finch
AVIATION...Sugden
AREA FORECAST DISCUSSION
NWS GREAT FALLS MT
1030 PM MST Fri Feb 14 2014
.DISCUSSION...
Update forthcoming as a few changes have been made. Winds along the
Rocky Mountain Front have decreased. Gusts to 40 or 45 mph are still
possible for the next few hours but RUC analysis continues to
indicate 700 mb winds will decrease overnight. Therefore, have
canceled the High Wind warning. Radar returns indicate snow
continuing to fall over the Rocky Mountain Front and, to a lesser
extent, the mountains of southwest Montana so will allow the winter
weather highlights to ride. Have lowered pops across most of the
Hi-Line for the remainder of the evening. Temperatures look good.
&&
.AVIATION...
UPDATED 0530Z.
Several weather disturbances pushing through Montana during the
period. Winds decreasing overnight along the Northern Rockies and
north central Montana. Areas of snow showers are possible over the
mountains of southwest Montana early in the period with a chance for
MFR conditions near the snow showers. Conditions will improve
Saturday morning and early afternoon with increasing cloudiness
after 00z and and areas of showers as the next disturbance moves in
from the west.
&&
.PREV DISCUSSION...ISSUED 244 PM MST Fri Feb 14 2014
Tonight through Sunday...Windy conditions will continue through
this evening over portions of North Central MT as an upper level
disturbance continues to move through the region.
Additionally...the westerly flow is allowing for snow to fall over
the Rocky Mountain Front and portions of Southwest MT. The best
snow accumulations will fall in the mountains...but a few mountain
pass roadways could be impacted through the evening hours...thus
the advisory will continue. The next change was to add a high wind
watch for all of North Central MT for late Saturday night through
Sunday night. Both the NAM/GFS continue to prog a fairly strong
wind event over much of the region...thus the watch has been
issued. There will continue to be a small chance for precip at
lower elevations over the weekend and a good chance for precip in
the mountains. At this time I held off on mentioning the potential
for freezing rain on Sunday as the westerly flow should keep the
precip either just rain or snow...however this will be watched
closely. Temperatures will continue to run a few degrees above
normal for most areas through the weekend. Brusda
Sunday night through Friday...A generally moist and unsettled
pattern will persist over the region through most of the forecast
period. Westerly flow brings dry conditions to the plains and
precipitation to the Continental Divide into Tuesday. A low pressure
system with ample Pacific moisture and associated cold front move
across Montana Tuesday night into Wednesday bringing accumulating
mountain snowfall to elevations above 5000 feet, with rain/snow mix
possible at lower elevations. Models remain in agreement that a
very unsettled period will linger Tuesday through Thursday as
multiple disturbance bring precipitation to various parts of Central
Montana. Timing and location of precipitation during this period is
somewhat poorly agreed upon; standard for a pattern of this nature.
In the wake of a secondary front passing Thursday, cold air will
move in from the north. Temperatures will drop noticeably but do not
look to go much below zero at this time. Overall temperatures will
remain warm into Wednesday before beginning a downward trend into
the weekend. With a moist and unstable pattern expected, POP was
raised quite a bit over the mountains, with valleys to a lesser
extent, during almost the entire long term forecast.
&&
.PRELIMINARY POINT TEMPS/POPS...
GTF 30 46 35 45 / 20 10 20 20
CTB 27 43 30 41 / 20 10 30 20
HLN 28 47 32 46 / 30 20 30 30
BZN 22 45 30 45 / 40 20 30 40
WEY 20 37 25 36 / 100 60 90 80
DLN 25 46 31 42 / 50 30 40 50
HVR 27 41 29 45 / 20 0 30 20
LWT 28 42 32 42 / 20 0 30 20
&&
.TFX WATCHES/WARNINGS/ADVISORIES...
HIGH WIND WATCH from late Saturday night through late Sunday
night Blaine...Cascade...Chouteau...Eastern Glacier...Eastern
Pondera...Eastern Teton...Fergus...Hill...Judith Basin...
Liberty...Northern Rocky Mountain Front...Southern Rocky
Mountain Front...Toole.
WINTER WEATHER ADVISORY until 5 AM MST Saturday Beaverhead...
Gallatin...Madison.
WINTER WEATHER ADVISORY until 5 AM MST Saturday Northern Rocky
Mountain Front...Southern Rocky Mountain Front.
&&
$$
weather.gov/greatfalls
www.twitter.com/NWSGreatFalls
www.facebook.com/US.NationalWeatherService.GreatFalls.gov
AREA FORECAST DISCUSSION
NWS RALEIGH NC
1212 AM EST FRI FEB 14 2014
.SYNOPSIS...AN UPPER LEVEL DISTURBANCE AND ATTENDANT SURFACE LOW
PRESSURE SYSTEM WILL CROSS THE REGION THIS MORNING. HIGH
PRESSURE WILL BUILD IN BEHIND THE SYSTEM ON SUNDAY.
&&
.NEAR TERM /THROUGH SATURDAY/...
AS OF 840 PM FRIDAY...
THE LATEST SURFACE ANALYSIS SHOWED A SURFACE LOW OVER KENTUCKY
MOVING EAST...WITH COOLING CLOUD TOPS MOVING OVER THE APPALACHIANS
ALTHOUGH THE HIGHER RADAR REFLECTIVITY WAS FARTHER WEST...BASICALLY
IN THE AXIS OF HIGHER PRECIPITABLE WATER VALUES ON THE LATEST SPC
MESOANALYSIS PAGE THAT EXTENDED ACROSS EASTERN KENTUCKY AND
TENNESSEE INTO ALABAMA AND NORTHWEST GEORGIA. THE LATEST KGSO
SOUNDING AT 00Z WAS VERY DRY...ALTHOUGH SURFACE DEW POINTS EVEN IN
THE NORTHWEST PIEDMONT...IN THE TEENS IN SOME PLACES VERY EARLY THIS
EVENING...HAD RISEN INTO THE UPPER 20S SUCH THAT DEW POINTS IN
CENTRAL NORTH CAROLINA RANGED FROM THE UPPER 20S TO THE MID 30S. IN
A FEW LOCATIONS...ESPECIALLY OVER PARTS OF THE SANDHILLS AND THE
COASTAL PLAIN WHERE CLOUDS WERE SLOWER MOVING IN...TEMPERATURES FELL
QUICKLY INTO THE UPPER 30S BUT THESE VALUES SHOULD STABILIZE GIVEN
THE DECENT SURFACE MOISTURE AND THE CLOUDS MOVING IN.
GOOD LIFT IS FORECAST BY THE GUIDANCE LATE TONIGHT WITH 850MB THETA-
E VALUES INCREASING AS THE STRONG MID-LEVEL TROUGH APPROACHES FROM
THE WEST. GOOD DIVERGENCE IS NOTED ON WATER VAPOR IMAGERY AND GOOD
DIVERGENCE IS ALSO FORECAST OVERNIGHT BY THE RAP. THE PRECIPITABLE
WATER AXIS IS FORECAST BY THE RAP TO MOVE INTO CENTRAL NORTH
CAROLINA BY 09Z...COINCIDENT WITH THE LATEST HRRR WHICH SHOWS THE
LEADING EDGE OF PRECIPITATION DEVELOPING A LITTLE FASTER OVER THE
SANDHILLS AND THE PIEDMONT BETWEEN 08Z AND 10Z NEAR WHERE THE RAP
FORECAST ABOUT 100J/KG OF MUCAPE IN THE LAYER BETWEEN 1000MB AND
700MB. THIS PRECIPITATION COULD SPREAD NORTHEAST TOWARD KRWI AND
KIXA PRIOR TO SUNRISE...SO HAVE SPED UP THE TIMING OF THE CHANCES
FOR PRECIPITATION AFTER MIDNIGHT. FOR THE OVERNIGHT HOURS...THE WET-
BULB ZERO TEMPERATURES RISE TO FREEZING OR ABOVE IN CENTRAL NORTH
CAROLINA BY 04Z...AND PARTIAL THICKNESSES ARE INDETERMINATE. SO...
REVIEWING THE BUFR AND RAP SOUNDINGS FOR THE ABOVE-FREEZING LAYER
DEPTH...THROUGH 12Z ALL OF THAT GUIDANCE IS SUFFICIENTLY DEEP WITH
THAT LAYER...AT LEAST TO NEAR 2000FT...TO KEEP THE TYPE LIQUID. MADE
SOME ADJUSTMENTS TO LOWS BASED UPON CURRENT TRENDS...A LITTLE COOLER
WHERE THE TEMPERATURES HAD FALLEN FASTER...AND A DEGREE OR TWO RISE
IN THE TRIAD DUE TO THE QUICKER ONSET OF CLOUDS. WILL CONTINUE THE
POTENTIAL FOR PATCHY FOG IN THE FORECAST BUT DELAYED THE TIMING TO
ONLY BE COINCIDENT WITH ANY CHANCES FOR RAIN.
SATURDAY...THE CLIPPER SURFACE WAVE WILL DEEPEN AS IT MOVES QUICKLY
ENE THROUGH CENTRAL AND EASTERN NC...BEFORE BOMBING AS IT TURNS NE
UP THE MIDDLE ATLANTIC COAST...BENEATH THE STRONGLY DYNAMIC AND
INCREASINGLY NEGATIVELY-TILTED TROUGH ALOFT. IN A SIMILAR SYNOPTIC
PATTERN AND RADAR PRESENTATION AS THE MID-UPPER LOW ON THU...THOUGH
ON A SLIGHTLY MORE SOUTHERN TRACK...A DEFORMATION BAND WILL DEVELOP
ON THE WEST SIDE OF THE RAPIDLY DEEPENING LOW...AND SUBSEQUENTLY
PIVOT EASTWARD THROUGH CENTRAL NC THROUGH MID AFTERNOON. BASED ON
THE HIGH BIAS DISPLAYED WITH PRECIPITATION AMOUNTS BY THE NWP
GUIDANCE FOR THE EVENT FROM THU...WILL FOLLOW THE MORE SUBDUED
CONSENSUS OF THE 12Z ECMWF/NAM OF AROUND ONE QUARTER INCH STORM
TOTAL RAIN. P-TYPE SHOULD INDEED BE JUST THAT - RAIN - OWING TO A
MILD AND RELATIVELY DEEP BOUNDARY LAYER THAT SHOULD COMPLETELY MELT
SNOWFLAKES GENERATED IN...AND FALLING FROM...A COLD/BELOW FREEZING
AND STEEP LAPSE RATE-BEARING LAYER ALOFT. THERE IS STILL A NON-ZERO
CHANCE OF SOME WET SNOWFLAKES ON THE VERY BACK SIDE OF THE
PRECIPITATION OVER THE NORTHERN PIEDMONT...MAINLY TOWARD THE TRIAD
AND KTDF...AROUND 15Z AS THE NAM BUFR AND RAP SOUNDINGS DIMINISH THE
ABOVE FREEZING LAYER BELOW 1000FT. THIS MAY BE OVERDONE...THOUGH...
GIVEN EXPECTED SURFACE TEMPERATURES...AND BY THEN IT IS ANTICIPATED
THE HIGHER-RATE PRECIPITATION WILL BE SHIFTING OFF TO THE EAST.
NEVERTHELESS...IF THE PACE OF PRECIPITATION IS SLOWER TO SHIFT EAST
THAN ANTICIPATED...THIS MAY HAVE TO BE REINTRODUCED TO THE FORECAST
BUT IMPACT...IF IT OCCURS...SHOULD BE QUITE SMALL OWING TO THE
SURFACE TEMPERATURES.
THE BIGGER STORY WILL BE VERY STRONG NW WINDS THAT WILL DEVELOP IN
THE TIGHT PRESSURE GRADIENT BEHIND THE DEPARTING LOW AND INCOMING
UPSTREAM HIGH PRESSURE. BUFR SOUNDINGS INDICATE MIXED LAYER WINDS OF
25-30 KTS...WITH WINDS AT THE TOP OF THE MIXED IN THE MID-UPPER 30S
KTS. THIS MIXING SHOULD SUPPORT SUSTAINED WINDS BETWEEN 15-25
KTS...WITH FREQUENT GUSTS OF 25-30 KTS...DEVELOPING AS THE CLEARING
SPREADS EAST AND THE MIXED LAYER DEEPENS.
&&
.SHORT TERM /SATURDAY NIGHT THROUGH MONDAY NIGHT/...
AS OF 300 PM FRIDAY...
AS LOW PRESSURE EXITS TO THE NORTHEAST SKIES WILL CLEAR OUT FOR MOST
OF SATURDAY NIGHT BEFORE CLOUDS BEGIN TO MOVE IN AGAIN EARLY SUNDAY
MORNING AS A MUCH DRIER...WEAKER CLIPPER SYSTEM APPROACHES FROM THE
NORTHWEST. IN ADDITIONS THE SURFACE FLOW WILL BECOME VERY WEEK AND
RADIATIONAL COOLING WILL ENSUE FOR MOST OF THE NIGHT...HELPING
TEMPERATURES DROP INTO THE MID TO UPPER 20S FOR LOWS SATURDAY NIGHT.
ON SUNDAY THE DRY CLIPPER SYSTEM DROPS THROUGH THE WEAKENING UPPER
LEVEL TROUGH. MOST OF THE LIMITED MOISTURE WITH THIS SYSTEM IS LEFT
ON THE WEST SIDE OF THE APPALACHIANS AND THE SYSTEM DRIES OUT PRETTY
QUICKLY. WILL LEAVE THE FORECAST DRY WITH SOME
CLOUDINESS...ESPECIALLY IN THE NORTH...THAT WILL HELP TO KEEP MAX
TEMPS DOWN ON SUNDAY. EXPECT MID 40S NW TO LOWER 50S ACROSS THE
SOUTH WHERE CLOUD COVER WILL BE LIMITED. SURFACE HIGH PRESSURE WILL
BUILD TO THE NORTHWEST...KEEPING NORTHERLY FLOW OVER CENTRAL NC
THROUGH SUNDAY NIGHT. THIS WEAK COLD AIR ADVECTION AND MOSTLY CLEAR
SKIES WILL ONCE AGAIN BRING LOWS SUNDAY NIGHT DOWN INTO THE MID 20S
TO LOW 30S.
ON MONDAY THE HIGH SHIFTS EASTWARD ACROSS THE MID ATLANTIC STATES
AND WILL TRY TO SET UP A BRIEF HYBRID/IN SITU CAD EVENT...DEPENDING
ON WHAT MODEL YOU BELIEVE. WHILE THE WEDGE FRONT WONT REALLY HAVE A
CHANCE TO GET LOCKED IN...IT WILL BE ENOUGH TO MAKE SKIES OVERCAST
BY MONDAY AFTERNOON WITH SOME DRIZZLE POSSIBLE...MAINLY ACROSS THE
NW PIEDMONT. HIGHS UPPER 40S NW TO MID 50S SE. BY MONDAY NIGHT THE
HIGH MOVES OFFSHORE AND WE BEGIN TO ENTER A WARM AIR ADVECTION
REGIME BETWEEN THE HIGH OFFSHORE AND AN APPROACHING FRONTAL SYSTEM
WEST OF THE MOUNTAINS. LOWS WILL MODERATE TO THE MID 30S TO UPPER
40S MONDAY NIGHT. WE WILL STAY DRY BUT MOISTURE WILL STEADILY
INCREASE INTO TUESDAY.
&&
.LONG TERM /TUESDAY THROUGH FRIDAY/...
AS OF 300 PM FRIDAY...
CONFIDENCE DECREASES IN THE FORECAST BY TUESDAY AS A FRONTAL SYSTEM
APPROACHES FROM THE WEST. WHILE THERE IS HIGH CONFIDENCE THAT A
FRONT WILL CROSS CENTRAL NC SOMETIME ON TUESDAY...DETAILS REGARDING
THE POSITION AND STRENGTH OF THE PARENT LOW AND AMOUNT OF QPF ARE
ALL MURKY AT THIS TIME. WE DO KNOW HOWEVER THAT WITH TEMPERATURES
EXPECTED TO BE IN THE 60S THAT THIS WILL BE AN ALL LIQUID EVENT.
MODEL SOUNDINGS SHOWN IN BUFKIT LEAD TO FAIRLY HIGH CONFIDENCE THAT
THERE WONT BE ANY INSTABILITY AVAILABLE ON TUESDAY FOR THUNDER. THE
FRONT WILL STALL OUT SOMEWHERE SOUTH OF THE AREA ON TUESDAY NIGHT
WITH LOWS GENERALLY IN THE LOW TO MID 40S.
ON WEDNESDAY MORNING THE FRONT WILL RETREAT BACK TO THE NORTH AS A
WARM FRONT AND CROSS THE AREA ONCE AGAIN...WITH PRECIPIATION
POSSIBLE INTO WEDNESDAY AFTERNOON. SOUNDINGS INDICATE THEIR MAY BE
WEAK SURFACE BASED CAPE OF LESS THAN 500 J/KG AVAILABLE OF THE VERY
TALL AND SKINNY VARIETY WITH A DECENT CAP AT 850MB THAT IT WOULD
HAVE TO BUST THROUGH...MAKING CONFIDENCE FOR THUNDER SLIGHTLY BETTER
FOR WEDNESDAY BUT STILL NOT LIKELY. WITH SW FLOW RETURNING HIGHS
WILL SOAR INTO THE MID 60S TO EVEN LOWER 70S POSSIBLE ACROSS THE
SOUTH. WEDNESDAY NIGHT SHOULD BE DRY WITH LOWS MODERATING TO THE
UPPER 40S TO LOW 50S.
FAIRLY STRONG LOW PRESSURE IS EXPECTED TO MOVE OUT OF THE MIDWEST UP
THROUGH THE GREAT LAKES REGION ON THURSDAY. CENTRAL NC WILL REMAIN
NICELY IN THE WARM SECTOR AHEAD OF THIS SYSTEM ON THURSDAY AND THE
ANCHORED BERMUDA HIGH WILL KEEP MOIST SOUTHERLY FLOW OVER THE AREA.
HIGHEST TEMPERATURES OF THE SEASON MAY BE IN ORDER AS HIGHS GO INTO
THE UPPER 60S TO MID 70S NW TO SE. WITH THE EXTRA MOISTURE EXPECT
PARTLY TO MOSTLY CLOUDY SKIES.
ON FRIDAY THE FRONTAL SYSTEM BECOMES MORE EAST TO WEST ORIENTED AS
THE PARENT LOW SPEEDS OFF TO THE NORTHEAST. EXPECT PRECIPITATION TO
OVERSPREAD THE ENTIRE AREA BY FRIDAY AFTERNOON. WITH A LOT OF
MOISTURE AVAILABLE THIS COULD SHAPE UP TO BE A FAIRLY HEAVY RAIN
EVENT BUT IT IS TOO EARLY TO TELL AT THIS TIME. HIGHS FRIDAY
DEPENDENT ON FRONTAL LOCATION.
&&
.AVIATION /06Z SATURDAY THROUGH TUESDAY/...
AS OF 1210 AM SATURDAY...
AN AREA OF LOW PRESSURE TRACKING THROUGH THE CAROLINAS TONIGHT
THROUGH MIDDAY WILL BRING A 3 TO 6 HOUR PERIOD OF SUB-VFR CEILINGS
AND RAIN TO ALL THE TERMINALS. VFR CONDITIONS ARE EXPECTED TO
RAPIDLY RETURN BETWEEN 15Z WEST AND 18Z-21Z EAST AS THE SYSTEM
DEPARTS SATURDAY. WINDS WILL SHIFT FROM SW TO NW AND BECOME VERY
STRONG AND GUSTY ONCE THE RAIN DEPARTS...WITH SUSTAINED WINDS OF 15
TO 20KT...GUSTING TO 25-35KT. WINDS WILL SUBSIDE AFTER DARK WITH A
FEW SPRINKLES POSSIBLE OVERNIGHT AS AN UPPER LEVEL DISTURBANCES
MOVES INTO THE AREA. OTHERWISE...DRY VFR CONDITIONS ARE EXPECTED
THROUGH EARLY NEXT WEEK.
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...DJF
NEAR TERM...MWS/DJF
SHORT TERM...ELLIS
LONG TERM...ELLIS
AVIATION...CBL
AREA FORECAST DISCUSSION
NWS GRAND FORKS ND
1147 PM CST FRI FEB 14 2014
.UPDATE...
ISSUED AT 1146 PM CST FRI FEB 14 2014
TEMPS HAVE BEGUN TO STEADY OR EVEN RISE IN A FEW PLACES WEST OF
THE RED RIVER AS CLOUDS AND WINDS PICK UP. THERE ARE SOME RADAR
ECHOES DEVELOPING OVER WESTERN ND ALTHOUGH NOT MUCH APPEARS TO BE
REACHING THE GROUND YET. THINK IT WILL BE A WHILE BEFORE
SATURATION SO KEPT MOST POPS IN THE WEST AFTER 12Z WHICH FITS THE
MOST RECENT MODEL RUNS. BETTER CHANCES IN FAR NORTHEASTERN CWA
WITH THE NORTHERN SHORTWAVE...SO CONTINUED TO KEEP HIGH POPS IN
NORTHERN LAKE OF THE WOODS.
UPDATE ISSUED AT 941 PM CST FRI FEB 14 2014
RADAR RETURNS OVER EASTERN MT HAVE BEEN SLOW TO ENTER THE WESTERN
PART OF ND AND HAVE SHOWN A BIT OF A WEAKENING TREND. THE 00Z NAM
IS QUITE A BIT LESS IMPRESSIVE WITH THE SNOW ENTERING OUR
SOUTHEASTERN CWA THAN PREVIOUS RUNS. THE 02Z RAP HAS THE PRECIP
DISSIPATING BEFORE IT EVEN ENTERS EASTERN ND. WANT TO GET A LOOK
AT THE 00Z GFS AND SEE THE SNOW ENTERING THE WESTERN PART OF THE
STATE BEFORE MAKING MORE RADICAL CHANGES TO POPS. FOR NOW...CUT
THEM QUITE A BIT FOR TONIGHT...KEEPING ONLY A SMALL SLIVER OUT IN
THE WEST BEFORE 12Z. ALSO MADE SOME MINOR ADJUSTEMENTS TO POPS FOR
TOMORROW BUT KEPT THE SOUTH AND WEST IN THE LIKELY CATEGORY FOR
NOW.
TEMP WISE...CLOUDS HAVE KEPT THE NORTHEAST A BIT WARMER THAN
EXPECTED WHILE THE SOUTHEAST HAS ALREADY DROPPED BELOW ZERO. THINK
THAT THE WESTERN COUNTIES SHOULD START RISING IN A FEW HOURS AS
SOUTHERLY WINDS AND CLOUDS MOVE INTO THE REGION. LOWERED LOWS A
BIT IN THE SOUTHERN COUNTIES WHERE BWP HAS ALREADY DROPPED TO
ZERO.
UPDATE ISSUED AT 627 PM CST FRI FEB 14 2014
MADE A FEW MINOR TWEAKS TO MATCH CURRENT CLOUD COVER...BUT NO
MAJOR CHANGES FOR THE EARLY EVENING UPDATE. CONTINUE TO THINK WE
SHOULD SEE A SHARP DROP OVER THE EASTERN COUNTIES AFTER SUNSET AND
THEN RISING TEMPS THROUGHOUT THE AREA FOR THE REST OF THE NIGHT.
&&
.SHORT TERM...(THIS EVENING THROUGH SATURDAY NIGHT)
ISSUED AT 302 PM CST FRI FEB 14 2014
THE MAIN CHALLENGE WILL BE SNOW POTENTIAL TONIGHT INTO SATURDAY
MORNING. MODELS ARE IN DECENT AGREEMENT...WITH ONLY MINOR
DIFFERENCES WITH QPF AND LOCATION. A COUPLE UPPER WAVES WILL
PROPAGATE THROUGH THE REGION LATER TONIGHT INTO SATURDAY. THE
STRONGEST FORCING FROM THESE FEATURES WILL MAINLY AFFECT THE SW FA
AND THE NE FA. MODELS KEEP THE FORCING FROM THESE FEATURES
SEPARATE UNTIL EAST OF THE REGION. THUS...EXPECT AROUND AN INCH OF
SNOWFALL ACROSS THESE AREAS (POSSIBLY A BIT HIGHER FOR NORTHERN
LAKE OF THE WOODS COUNTY).
TEMPERATURES TONIGHT WILL LIKELY FALL UNTIL CLOUDS ARRIVE...THEN
STEADY OR SLOWLY RISE. USED THE CONSSHORT GUIDANCE FOR HOURLY
VALUES.
HIGH PRESSURE MOVES THROUGH THE REGION SATURDAY NIGHT...THUS
LOWERED MIN TEMPS A FEW DEGREES.
.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 302 PM CST FRI FEB 14 2014
SUNDAY-MONDAY...UPPER FLOW WILL BECOME ZONAL AHEAD OF THE NEXT
UPPER WAVE. MODELS ALL INDICATE A PERIOD OF 850MB WARM AIR
ADVECTION SNOW THAT WILL MOVE THROUGH THE AREA SUNDAY
AFTERNOON/NIGHT ASSOCIATED WITH THE UPPER WAVE. THERE IS STILL
SOME DISAGREEMENT WITH EXACTLY HOW/WHEN THIS EVENT WILL
UNFOLD...AND EXACTLY WHERE THE HEAVIEST SNOWFALL WILL BE LOCATED.
AT ANY RATE...1-3 INCHES MOST AREAS...POSSIBLY SLIGHTLY MORE ACROSS
THE SOUTHEAST FA. AHEAD OF THE SNOW...SOUTHERLY WINDS WILL BE BREEZY
(SUNDAY AFTERNOON). MUCH LIKE PAST SOUTHERLY WIND
EVENTS...ANTICIPATE AT LEAST PATCHY BLOWING SNOW ACROSS THE
NORTHERN RED RIVER VALLEY (AND INSERTED THIS INTO THE FORECAST).
SYNOPTIC PATTERN IS SUCH THAT LOW LEVEL WESTERLY FLOW...AND A
WARMER AIRMASS...SHOULD LEAD TO MAX TEMPS NEAR FREEZING ON MONDAY.
MONDAY NIGHT-FRIDAY...LONG TERM WILL SEE A SHIFT FROM A ZONAL
PATTERN EARLY IN THE PERIOD TO LONG WAVE TROUGHING OVER ROCKIES BY
NEXT WEEKEND. WILL SEE A SERIES OF SHORT WAVE TROUGH/RIDGES MOVE
THROUGH IN THE MID WEEK...WITH CHANCES OF SNOW AROUND DAY 6/7.
WITH THE ZONAL PATTERN AND UPPER WAVES MOVING ACROSS SRN
CANADA...SEEING A LOT OF LOW POPS FOR THE SECOND HALF OF THE
PERIOD. BEST CHANCE...HOWEVER...APPEARS TO BE WED NIGHT INTO THU
AS A DEEPER WAVE MOVES ACROSS THE NORTHERN TIER. ECMWF SHOWS A LOW
MOVING OUT OF WYOMING WED AND INVERTED TROUGH LIFTING INTO THE
VALLEY WED NIGHT...HOWEVER PRECIP MAY BE MOSTLY ACROSS THE NORTH
OR SOUTHERN MANITOBA. TEMPS WILL BE IN THE LOW 30S FOR MUCH OF THE
FIRST HALF OF THE WEEK.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT)
ISSUED AT 1146 PM CST FRI FEB 14 2014
VFR CONDITIONS WILL CONTINUE THROUGH SATURDAY MORNING WITH
INCREASING HIGH AND MID LEVEL CLOUDS OVERNIGHT. MODELS BEGIN
BRINGING IN SOME MVFR CIGS BEHIND A COLD FRONT LATE MORNING INTO
THE AFTERNOON. THERE HAS ALSO BEEN A TREND TOWARDS NORTHERLY WINDS
PICKING UP TO AROUND 15 KTS SO BUMPED UP WINDS A BIT. THINK THAT
SNOW WILL STAY AWAY FROM TAF SITES AT THIS POINT SO WILL NOT
INCLUDE FOR NOW. VFR CONDITIONS WILL RETURN TOWARDS THE END OF THE
PERIOD AND WINDS WILL START TO DIMINISH.
&&
.FGF WATCHES/WARNINGS/ADVISORIES...
ND...NONE.
MN...NONE.
&&
$$
UPDATE...JR
SHORT TERM...TG
LONG TERM...TG/SPEICHER
AVIATION...JR
AREA FORECAST DISCUSSION
NWS GREENVILLE-SPARTANBURG SC
1245 AM EST SAT FEB 15 2014
.SYNOPSIS...
AN UPPER LEVEL SYSTEM WILL QUICKLY MOVE OFF THE MID ATLANTIC COAST
TODAY AS HIGH PRESSURE BUILDS IN FROM THE WEST. A COLD FRONT WILL
REACH OUR AREA FROM THE WEST MONDAY NIGHT ON TUESDAY. EXPECT A
SOUTHERLY WIND FLOW TO BRING MUCH ABOVE NORMAL TEMPERATURES LATE IN
THE WEEK.
&&
.NEAR TERM /THROUGH TODAY/...
930 PM UPDATE...PATCHES OF LIGHT PRECIP SEEN ON RADARS ATTM FROM FAR
ERN KY AND SRN WV DOWN THRU THE GREAT VALLEY AND INTO ERN AL. THESE
ARE ALL AHEAD OF THE UPPER SHORTWAVE. SFC OBS INDICATE RATES OF A
FEW HUNDREDTHS PER HOUR. SPC MESOANALYSIS SUGGESTS THE NE ALABAMA
ACTIVITY...WHICH PER TRENDS WOULD AFFECT OUR CWFA THE MOST...IS
OCCURRING IN AN AREA OF WEAK WARM UPGLIDE AHEAD OF THE BASE OF THE
850MB TROUGH. RUC PROGS SUGGEST THIS FORCING DIVES SEWD ACRS GA AND
INTO THE SC MIDLANDS...BUT THEY STILL SHOW SOME LIGHT QPF CROSSING
THE FA DIRECTLY AHEAD OF THE UPPER WAVE AND REASONABLY CLOSE TO
EARLIER TIMING. TWEAKED POPS DOWNWARD THIS EVENING TO ACCOUNT FOR
THE SPOTTY NATURE OF THE ACTIVITY NOW ENTERING SW NC AND NE GA...BUT
OVERALL POPS LOOK REASONABLE...AND THE PRECIP RATES SUGGESTED BY THE
GOING QPF ARE OK. 00Z NAM SEEMS TO MOVE THE PRECIP OUT FASTER
TOMORROW MORNING. TEMPS AND DEWPOINTS WERE OK BUT DID TOUCH THEM UP
ONCE AGAIN PER SHORT TERM CONSENSUS GUIDANCE. NEW TEMPS ARE SOMEWHAT
WARMER ESPECIALLY EARLY IN THE EVENT IN THE MTNS...WHICH REDUCES THE
STORM TOTAL SNOWFALL IN SOME PLACES DUE TO HIGHER SNOW LEVELS THIS
EVENING. WILL REISSUE WSW PRODUCT SHORTLY BUT WORDING WILL LIKELY BE
VERY CLOSE TO THAT ALREADY USED.
700 PM UPDATE...REVISED POPS...AND TO A LESSER EXTENT QPF...
FOLLOWING THE 18Z NAM/GFS AND 15Z SREF. THE MODELS GENERALLY AGREE
ON A WAVE OF PRECIP PASSING THRU THE PIEDMONT BEFORE DAYBREAK.
ISENTROPIC FORCING DOES LOOK PRETTY LIMITED BUT IT IS HARD TO IGNORE
THE DYNAMIC LIFT AND DEEP COLUMN OF MOISTURE PROGGED TO CROSS WITH
THE SHORTWAVE. ALSO RECALL THAT THE TRACK OF THIS WAVE IS PRETTY
SIMILAR TO THAT THURSDAY MORNING...WHICH THE NAM/GFS CORRECTLY
INDICATED WOULD BRING PRECIP TO THE PIEDMONT IN ITS DEFORMATION
ZONE. THUS FELT CONFIDENT ENOUGH TO GO CATEGORICAL...IF NOT
BRIEFLY...IN A BAND TRAVERSING THE CWFA. QPF STILL LOOKED PRETTY
GOOD BUT MADE CHANGES MAINLY EAST OF THE SNOW AREA. IT CONTINUES TO
LOOK LIKE THE COLDER AIR CAPABLE OF ALLOWING SNOW TO REACH THE
SURFACE EAST OF THE MTNS/FOOTHILLS WILL NOT PUSH IN FAST ENOUGH TO
ALLOW MUCH SNOW ACCUMULATION. SNOW MENTION IS A BIT LESS EXPANSIVE
OVER THE NC PIEDMONT AS A RESULT. IN THE MTNS...ACCUMS ARE PRETTY
SIMILAR WITH THE ONLY TOTALS ABOVE ADVY CRITERIA SHOWN IN THE
HIGHEST ELEVATIONS. TEMP/DEWPT TRENDS FROM EARLIER UPDATE STILL LOOK
TO BE ON TRACK.
ON ANOTHER NOTE...TAKING ANOTHER LOOK AT WINDS SUNDAY...THE GRADIENT
APPEARS TO RELAX FAST ENOUGH TO ALLOW THE WIND ADVY TO EXPIRE MUCH
EARLIER THAN PREVIOUSLY THOUGHT. WILL TRIM IT BACK TO END SATURDAY
EVENING.
AT 215 PM EST FRIDAY...A STRONG SHORTWAVE WILL DIVE INTO THE BASE OF
AN EASTERN NORTH AMERICAN TROUGH TONIGHT...REACHING THE CENTRAL
CAROLINAS BY SATURDAY MORNING. THIS SHORTWAVE WILL MOVE UP THE EAST
COAST ON SATURDAY.
MODEST ISENTROPIC UPGLIDE WILL SPREAD OVER THE MOUNTAINS ATE THIS
EVENING...AND THE FOOTHILLS AND PIEDMONT SHORTLY THEREAFTER...
SUPPORTING THE DEVELOPMENT OF PRECIPITATION AHEAD OF AN APPROACHING
COLD FRONT. MODEL SOUNDINGS SHOW MOISTURE EXTENDING TO LEVELS COLD
ENOUGH FOR ICE NUCLEATION...BUT LOWER LEVELS WILL INITIALLY BE WARM
ENOUGH FOR RAIN. WITH NO WARM NOSE ALOFT...THIS WILL BE A
RAIN/SNOW SETUP. AS THE NIGHT PROGRESSES...SNOW LEVELS FALL TO THE
FLOORS OF THE MOUNTAINS VALLEYS...AND BRIEFLY TO THE SURFACE IN THE
LEE OF THE MOUNTAINS...MAINLY IN WESTERN NC. MINIMUM TEMPERATURES
ARE EXPECTED TO BE NEAR NORMAL...AND ABOVE FREEZING EAST OF THE
MOUNTAINS. SNOW ACCUMULATIONS EAST OF THE BLUE RIDGE ARE NOT
EXPECTED.
FRONTAL PASSAGE BEFORE DAWN WILL BE FOLLOWED BY MOISTURE WRAPPING
AROUND A DEEPENING SURFACE LOW OVER THE INTERSTATE 77 CORRIDOR OF
NC. PRECIPITATION MAY LINGER IN THE WESTERN NC PIEDMONT FOR A FEW
HOURS AFTER DAYBREAK BEFORE THE SURFACE LOW MOVES OFF TO THE NE AND
TAKES THE MOISTURE WITH IT. A TRANSITION FROM SNOW TO RAIN IS
EXPECTED DURING THIS TIME FRAME.
GUSTY NW WINDS BEHIND THE FRONT MAY SUPPORT A WIND ADVISORY NEAR THE
BLUE RIDGE ON SATURDAY. MOIST NW FLOW SNOW WILL SET UP BEHIND THE
FRONT...WITH SNOW CONTINUING IN THE NC MOUNTAINS UNTIL DRYING AT
MIDDAY. MOST ACCUMULATIONS WILL BE ABOVE 3500 FEET...WHERE WINTER
WEATHER ADVISORY CRITERIA ARE EXPECTED TO BE MET. A FEW LOCATIONS
NEAR THE TN BORDER COULD RECEIVE FOUR TO FIVE INCHES...BUT THE
COVERAGE WOULD BE TOO CONFINED TO ISSUE A WARNING FOR THOSE
COUNTIES. HIGH TEMPERATURES SATURDAY WILL RUN SLIGHTLY BELOW NORMAL
IN THE LEE OF THE MOUNTAINS AS COLD ADVECTION OFFSETS DOWNSLOPE FLOW
WARMING. TEMPERATURES IN THE MOUNTAINS WOULD RUN ALMOST 12 DEGREES
BELOW NORMAL IN COLD ADVECTION.
&&
.SHORT TERM /TONIGHT THROUGH MONDAY/...
AS OF 2 PM FRIDAY...WE BEGIN A WELL-DESERVED PERIOD OF RELATIVELY
QUIET WEATHER. ONE LAST SHORT WAVE IS EXPECTED TO DROP DOWN INTO THE
MEAN UPPER TROF OVER THE EAST ON SATURDAY NIGHT...AND IT WILL PASS
EARLY ON SUNDAY MORNING. THIS WAVE WILL BRING SOME MOISTURE DOWN
FROM THE NORTHWEST ON SUNDAY MORNING. THE LOW LEVEL FLOW AHEAD OF
THE WAVE WILL BE WESTERLY...SO ALTHOUGH WE WILL HAVE SOME MID LEVEL
FORCING WITH THE PASSAGE OF THE WAVE...THE LOW LEVELS WILL NOT BE
COOPERATIVE FOR PRECIP PRODUCTION ON THE TN BORDER. WE ARE CARRYING
A SLIGHT CHANCE POP OVER THE NORTHERN MTNS AND IT APPEARS THIS
SHOULD SUFFICE...FOR SNOW SHOWERS MAINLY SUNDAY MORNING. ONCE THAT
WAVE PASSES...THE UPPER PATTERN DEAMPLIFIES AND BEGINS A PERIOD OF
NEARLY ZONAL FLOW INTO MONDAY AND BEYOND. A SHORT WAVE MOVING UP THE
OH VALLEY ON MONDAY WILL DRAW MOISTURE FROM THE GULF WITH A
DEVELOPING SOUTHERLY UPSLOPE COMPONENT. THIS COULD FORCE SOME SHOWER
ACTIVITY OVER THE MTNS AND JUST E OF THE BLUE RIDGE IN THE AFTERNOON
AS THE MOISTURE INCREASES. OTHERWISE...WE ARE LOOKING AT TEMPS
SLOWLY MODERATING...WITH A RETURN TO NORMAL ON SUNDAY AND SUNDAY
NIGHT...AND THEN SLIGHTLY ABOVE NORMAL ON MONDAY.
&&
.LONG TERM /MONDAY NIGHT THROUGH FRIDAY/...
AS OF 210 PM EST FRIDAY...ZONAL FLOW ACROSS THE CONUS WILL GIVE WAY
TO AN RNA PATTERN LATER IN THE MEDIUM RANGE AS A TROUGH DIGS ACROSS
THE WRN US...INDUCING RIDGING OVER THE EAST.
MONDAY NIGHT A FAST MOVING SOUTHERN STREAM SHORT WAVE WILL CROSS THE
REGION. BASED ON THE LLVL TEMPERATURE PROFILE...PCPN WITH THIS
FEATURE SHOULD BE ALL RAIN. WITH THE BEST OF THE FORCING EXPECTED TO
PASS NORTH OF THE REGION...QPF SHOULD BE LIGHT WITH THE WAVE IN ANY
EVENT.
TEMPERATURES WILL WARM CONSIDERABLY ON TUESDAY WITH MAX TEMPS
EXPECTED TO RUN ABOUT 10 DEGREES ABOVE NORMAL ACROSS THE REGION. ON
WEDNESDAY THE LONG WAVE RIDGE WILL BEGIN TO BUILD ACROSS THE
SOUTHEAST STATES...YIELDING AN EVEN WARMER DAY. ONE POTENTIAL CAVEAT
IS THAT THE GFS SHOWS QUITE A BIT OF LLVL MOISTURE. AS WARM
ADVECTION INCREASES...AND THE COLD AIRMASS IS GRADUALLY DISPLACED
BY MUCH WARMER AIR...WE COULD SEE QUITE A BIT OF STRATUS TUESDAY AND
WEDNESDAY MORNINGS. THERE MAY BE SOME LIGHT SHOWER ACTIVITY OVER AND
NEAR THE BLUE RIDGE BY EARLY WEDNESDAY MORNING AS PW/S INCREASE TO
150-175 PERCENT OF NORMAL ON THE GFS.
SOUTHWESTERLY FLOW WILL BECOME STRONGER ON THURSDAY AS THE RIDGE
BUILDS AND A SHORT WAVE LIFTS ACROSS THE UPPER MID-WEST. THE
RESULTING INCREASE IN MOISTURE AND UPSLOPE FLOW MAY TRIGGER SHOWER
ACTIVITY OVER THE REGION...ESPECIALLY ACROSS THE MOUNTAINS AND
FOOTHILLS. THIS SEAMS REASONABLE AND WE HAVE SHOWERS OVER ALL BUT
THE SOUTHEAST TIER OF COUNTIES FOR THURSDAY.
THE LOW LIFTING ACROSS THE GREAT LAKES MAY PUSH A COLD FRONT INTO
THE REGION BY FRIDAY. WE WILL SEE JUST HOW FAR THAT BOUNDARY WILL
PUSH UNDER SOUTHWESTERLY FLOW ALOFT. THE ECMWF CAPE VALUES INCREASE
TO OVER 1000 J/KG OVER THE FOOTHILLS AND PIEDMONT. THE GFS DEWPOINTS
RISE INTO THE 60S...ALSO SUPPORTIVE OF DEEP CONVECTION. THEREFORE I
HAVE SHOWERS AND THUNDERSTORMS IN FOR FRIDAY. IT/S WAY TOO EARLY TO
ASCERTAIN THE SEVERE THREAT...THOUGH THE ANAFRONT NATURE OF THE
SYSTEM WOULD BE MORE SUPPORTIVE OF HEAVY RAIN OUT AT DAY 7 AND
BEYOND.
&&
.AVIATION /06Z SATURDAY THROUGH WEDNESDAY/...
AT KCLT...THE LEADING EDGE OF STEADIER RAIN IS MAKING STEADY EASTWARD
PROGRESS ACRS THE UPSTATE ATTM...WITH THE BEST PERIOD OF LIFT AND
MOISTURE EXPECTED TO AFFECT THE TERMINAL BETWEEN 07-11Z. DURING THIS
TIME...TEMPORARY RESTRICTIONS TO MVFR DUE TO RAIN AND/OR CIGS ARE
EXPECTED. TOWARD THE START OF THE MORNING PUSH TIME...WINDS SHOULD
HAVE VEERING TO WSW WITH A SWITCH TO WNW OR NW SHORTLY THEREAFTER.
IN THE IMMEDIATE WAKE OF THE EARLY MORNING WAVE PASSAGE...CAA AND
SFC PRESSURE RISES SHOULD CAUSE THE WESTERLY WIND TO BECOMING GUSTY
AND REMAIN THAT WAY FOR MUCH OF THE DAY. A QUICK IMPROVEMENT TO VFR
SHOULD OCCUR NOT TOO FAR AFTER DAYBREAK.
ELSEWHERE...AHEAD OF A FAST MOVING S/WV TROUGH...A PERIOD OF RAIN AND
MTN SNOW...ALONG WITH MVFR CIGS IS EXPECTED DURING THE PRE-DAWN
HOURS. WINDS WILL VEER TO WESTERLY AND BECOME GUSTY DURING THE EARLY
TO MID-MORNING HOURS AS PCPN CHANCES END EAST OF THE BLUE RIDGE. CIG
RESTRICTIONS AND SNOW SHOWER CHANCES WILL BECOMING INCREASINGLY
CONFINED TO THE TENNESSEE BORDER COUNTIES AS THE MORNING WEARS ON
BEFORE ENDING ALTOGETHER THIS AFTERNOON.
OUTLOOK...VFR BUT BREEZY CONDITIONS ARE TONIGHT AND THRU THE
WEEKEND. PRECIP OR LOW CIGS MAY RETURN WITH A FRONTAL PASSAGE MONDAY
NIGHT. THE SOUTHEAST U.S. SHOULD SEE A SPRINGLIKE WARM AND WET
PATTERN LATER IN THE WEEK...WITH SHRA/TSRA CAUSING SPOTTY
RESTRICTIONS.
CONFIDENCE TABLE...
05-11Z 11-17Z 17-23Z 23-05Z
KCLT HIGH 100% HIGH 100% HIGH 100% HIGH 95%
KGSP HIGH 100% HIGH 100% HIGH 100% HIGH 92%
KAVL HIGH 100% HIGH 100% HIGH 100% HIGH 84%
KHKY HIGH 100% HIGH 100% HIGH 100% HIGH 82%
KGMU HIGH 100% HIGH 100% HIGH 100% HIGH 92%
KAND HIGH 100% HIGH 100% HIGH 100% HIGH 92%
THE PERCENTAGE REFLECTS THE NUMBER OF GUIDANCE MEMBERS AGREEING
WITH THE SCHEDULED TAF ISSUANCE FLIGHT RULE CATEGORY. COMPLETE
HOURLY EXPERIMENTAL AVIATION FORECAST CONSISTENCY TABLES AND ENSEMBLE
FORECASTS ARE AVAILABLE AT THE FOLLOWING LINK: (MUST BE LOWER CASE)
WWW.WEATHER.GOV/GSP/AVIATION_TABLES
&&
.GSP WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
NC...WIND ADVISORY FROM 6 AM THIS MORNING TO 6 PM EST THIS EVENING
FOR NCZ033-049-050-052-053-064-065-501-503-505-507-509.
WINTER WEATHER ADVISORY UNTIL 1 PM EST THIS AFTERNOON FOR
NCZ033-048>052-058-059-062-063.
SC...WIND ADVISORY FROM 6 AM THIS MORNING TO 6 PM EST THIS EVENING
FOR SCZ003.
&&
$$
SYNOPSIS...JAT
NEAR TERM...JAT/WIMBERLEY
SHORT TERM...PM
LONG TERM...MCAVOY
AVIATION...CSH/WIMBERLEY
AREA FORECAST DISCUSSION
NWS MORRISTOWN TN
420 AM EST SAT FEB 15 2014
.SHORT TERM...(TODAY AND TONIGHT)...(TODAY AND TONIGHT)...LOW PRESSURE
OVER WRN NC AND CENTRAL VA CONTINUES TO MOVE EAST TO NORTHEAST
THIS MORNING. THE ASSOCIATED COLD FRONT HAD JUST MOVED EAST OFF THE
CUMBERLAND PLATEAU AT 09Z. TEMPS STAYED ON THE MILD SIDE OVERNIGHT
AND HAD JUST RECENTLY FALLEN BELOW 32 DEGREES ACROSS OUR NRN
PLATEAU COUNTIES AND PARTS OF LEE AND WISE COUNTIES OF SW VA.
WRAP AROUND MOISTURE WILL CONTINUE TO AFFECT MAINLY SW VA AND NE TN
THIS MORNING...BUT WAS ALREADY BECOMING VERY SHALLOW OVER WRN AREAS.
THE MOISTURE DECREASE AND MILD TEMPS OVERNIGHT SEVERELY HINDERED
GETTING MUCH SNOW ACCUMULATIONS ON OUR PLATEAU AND CENTRAL VALLEY
COUNTIES...SO OPTED TO CANCEL THE WINTER WEATHER ADVISORY FOR THOSE
AREAS. KEEPING THE ADVISORY AND WARNING AREAS INTACT FOR NOW FOR SW
VA...NE TN AND THE NRN/SMOKY MTNS OF E TN. RUC AND NAM MODELS SHOW A
DECENT AMOUNT OF W-NW UPSLOPE LOW LEVEL FLOW AND SOME INSTABILITY
THROUGH THE MORNING HOURS...PLUS SOUNDINGS IN THESE AREAS INDICATED
A GOOD POSSIBILITY OF SNOW OCCURRING ABOVE 2500 TO 3000 FEET
OVERNIGHT.
OTHERWISE...TEMPS WILL PROBABLY MAX OUT THIS MORNING OR AT BEST WARM
A FEW DEGREES IN THE AFTERNOON WITH SUNSHINE EXPECTED. MID AND HIGH
CLOUDS SHOULD INCREASE TONIGHT WHICH SUPPORTED MORE OF A BLEND OF
THE DIFFERING MOS MINS. ANY PRECIPITATION FOR TONIGHT APPEARS TO BE
A TRACE EVENT WITH FLURRIES...WHICH WAS DOWNPLAYED IN THE GRIDS.
LATER SHIFTS MAY BE ABLE TO DROP ALL MENTION OF ANY FLURRIES FOR
TONIGHT.
.LONG TERM...(SUNDAY THROUGH FRIDAY)...WEAK DISTURBANCE IN NW FLOW
WILL BRUSH NE TN AND SW VA SUNDAY MORNING. SOME LIGHT SNOW OR SNOW
FLURRIES WILL END BY LATE MORNING THEN WEAK HIGH PRESSURE WILL
BUILD ACROSS THE FORECAST AREA WITH FLOW BECOMING MORE ZONAL. SKIES
WILL BECOME MOSTLY SUNNY CENTRAL AND SOUTH WITH TEMPERATURES WARMING
TO NEAR AVERAGE ACROSS THE SOUTH AND CENTRAL BUT LINGERING CLOUDS
ACROSS THE NORTH WILL KEEP HIGHS THERE IN THE UPPER 30S TO LOWER
40S. SUNDAY NIGHT HIGH PRESSURE BEGINS TO SHIFT EAST. MONDAY LOW
PRESSURE OVER THE SOUTHERN PLAINS AND DEVELOPING FRONTAL SYSTEM
SPREADS CLOUDS INTO THE TN VALLEY WITH CHANCE OF RAIN BY AFTERNOON.
SOUTH TO SOUTHWEST WINDS AHEAD OF THE FRONT WILL WARM TEMPERATURES
INTO THE 50S. THIS IS THE BEGINNING OF A MUCH WARMER PATTERN. AS THE
FRONT MOVES THROUGH MONDAY NIGHT SKIES WILL CLEAR EARLY TUESDAY AS
HIGH PRESSURE SHIFTS EAST. TUESDAY WILL CONTINUE TO BE MILDER AND
SUNNY WITH HIGHS IN THE 50S TO LOWER 60S. TUESDAY NIGHT MOISTURE
SPREADS BACK NORTH AND AN UNSETTLED PATTERN SETS UP WITH SHOWERS
WEDNESDAY AS A DEEPER AREA OF LOW PRESSURE FORMS OVER THE PLAINS BY
WEDNESDAY NIGHT. THIS STRONGER SYSTEM BRINGS EVEN WARMER CONDITIONS
WEDNESDAY AND THURSDAY AS THE MAIN FRONTAL SYSTEM APPROACHES. SHOWERS
AGAIN WILL BE ON THE INCREASE WITH THE AIR MASS BECOMING UNSTABLE
THURSDAY INTO FRIDAY WITH THUNDERSTORMS POSSIBLE AS HIGHS REACH
INTO THE 60S IN ALL BUT THE HIGHER ELEVATIONS BOTH DAYS.
&&
.PRELIMINARY POINT TEMPS/POPS...
CHATTANOOGA AIRPORT, TN 38 29 53 32 58 / 10 10 10 10 30
KNOXVILLE MCGHEE TYSON AIRPORT, TN 38 28 49 30 55 / 20 20 10 10 30
OAK RIDGE, TN 36 27 50 30 54 / 20 20 10 10 30
TRI CITIES AIRPORT, TN 35 22 42 24 49 / 50 20 20 10 20
&&
.MRX WATCHES/WARNINGS/ADVISORIES...
NC...NONE.
TN...WINTER WEATHER ADVISORY UNTIL 10 AM EST THIS MORNING FOR THE
FOLLOWING ZONES: HANCOCK...HAWKINS...NORTHWEST CARTER...
NORTHWEST GREENE...SULLIVAN...WASHINGTON TN.
WINTER STORM WARNING UNTIL 1 PM EST THIS AFTERNOON FOR THE
FOLLOWING ZONES: BLOUNT SMOKY MOUNTAINS...COCKE SMOKY
MOUNTAINS...JOHNSON...SEVIER SMOKY MOUNTAINS...SOUTHEAST
CARTER...SOUTHEAST GREENE...SOUTHEAST MONROE...UNICOI.
VA...WINTER WEATHER ADVISORY UNTIL 10 AM EST THIS MORNING FOR THE
FOLLOWING ZONES: LEE...RUSSELL...SCOTT...WASHINGTON.
WINTER STORM WARNING UNTIL 1 PM EST THIS AFTERNOON FOR THE
FOLLOWING ZONES: WISE.
&&
$$
TG/TD
AREA FORECAST DISCUSSION
NWS CHEYENNE WY
1038 PM MST FRI FEB 14 2014
.SHORT TERM...(THIS EVENING THROUGH SUNDAY NIGHT)
ISSUED AT 355 PM MST FRI FEB 14 2014
CURRENT OBSERVATIONS ACROSS THE AREA SHOW WINDS JUST STARTING TO
INCREASE OVER SOUTHEAST WYOMING AND THE LAPS ANALYSIS SHOWS
SURFACE PRESSURE FALLS TO THE EAST OF THE MOUNTAINS. WINDS AT
ARLINGTON HAVE INCREASED ALL AFTERNOON AND ARE NOW OBSERVING GUSTS
AROUND 50 MPH. WINDS WILL CONTINUE TO INCREASE THIS EVENING WITH
GUSTS AROUND 60 MPH BY SUNSET. THE WEAK CLIPPER...WHICH IS
PLAYING A ROLE IN THE HIGH WINDS FOR TONIGHT...WILL DIG SOUTHEAST
INTO THE DAKOTAS AS AN ASSOCIATED COLD FRONT SLIDES SOUTH AND
STALLS ACROSS THE FORECAST AREA LATE TONIGHT AND EARLY SATURDAY.
SNOWFALL IS LOOKING MORE LIKELY ACROSS THE HIGH PLAINS OF SE
WYOMING AND IN THE MOUNTAINS TONIGHT THROUGH SATURDAY MORNING.
WILL HAVE TO MONITOR SNOWFALL AMOUNTS SINCE THE SREF IS SHOWING
DECENT QPF AMOUNTS ACROSS THE SNOWY RANGE...ALBANY COUNTY...AND
PORTIONS OF PLATTE AND CONVERSE COUNTY INCLUDING THE NORTHERN
LARAMIE RANGE. LLVL CONVERGENCE NEAR THE FRONT AND UPPER LEVEL JET
DYNAMICS MAY RESULT IN MODERATE TO LOCALLY HEAVY SNOWFALL RATES
FOR A WHILE TONIGHT. 3 TO 6 INCHES OF SNOW IS POSSIBLE IN THE
SNOWY RANGE AND NORTHERN LARAMIE RANGE...BUT WITH HIGH WINDS BEING
THE MAIN HAZARD...WILL JUST MENTION THE SNOW POTENTIAL IN THE HIGH
WIND WARNING FOR THE SNOWY RANGE. THE LOWER ELEVATIONS ARE A
LITTLE MORE TRICKY DUE TO SNOW LEVELS AND SOMEWHAT WARMER
TEMPERATURES AHEAD OF THE FRONT. FOR NOW...EXPECT 1 TO 2 INCHES OF
SNOW NORTH OF A LINE FROM LARAMIE TO CHADRON NEBRASKA. WOULD NOT
BE SURPRISED IF A FEW AREAS OBSERVE NEAR 4 INCHES IN THE HEAVIER
SNOW BANDS. HOWEVER...DID NOT ISSUE A WINTER WEATHER ADVISORY
SINCE THERE IS LOW CONFIDENCE ON WHERE THESE AREAS MIGHT BE. THERE
IS ADDITIONAL CONCERN THAT ANY HEAVIER SNOWFALL MAY ACCUMULATE
RAPIDLY SINCE TEMPERATURES DID NOT GET AS WARM AS PREVIOUSLY
EXPECTED DUE TO CLOUD COVER AND SOME REMAINING SNOW PACK. FURTHER
SOUTH ALONG I80...LITTLE OR NO SNOW IS EXPECTED AS THE FRONT
STALLS NEAR THE COLORADO BORDER. INCREASED POP BETWEEN 60 TO 80
PERCENT ALONG AND NORTH OF THE PLATTE RIVER VALLEY IN ADDITION TO
ALBANY COUNTY...WITH LOWER VALUES FURTHER SOUTH.
BY SATURDAY AFTERNOON...DRIER WEATHER IS EXPECTED THROUGH SATURDAY
NIGHT AS A SHORTWAVE RIDGE MOVES OVER THE FORECAST AREA. HIGH
TEMPERATURES WILL CLIMB INTO THE 40S ACROSS MOST OF THE AREA...BUT
REMAIN NEAR 40 FURTHER NORTH. STILL KEPT HIGH TEMPERATURES A FEW
DEGREES BELOW MOS SINCE THERE HAS BEEN A BIT OF A WARM BIAS
RECENTLY. GUSTY WEST TO SOUTHWEST WINDS ARE LIKELY AGAIN LATE
SATURDAY NIGHT INTO SUNDAY MORNING AS THE NEXT COLD FRONT MOVES
TOWARDS THE AREA. IN ADDITION...GUSTS UP TO 60 MPH ARE POSSIBLE
OVER THE WIND PRONE AREAS WEST OF THE LARAMIE RANGE. ALTHOUGH SOME
PRECIPITATION IS EXPECTED WITH THIS NEXT FRONT ON SUNDAY...EXPECT
IT TO BE LIGHT SINCE THIS UPPER LEVEL DISTURBANCE IS MORE
PROGRESSIVE IN NATURE AND WILL QUICKLY EXIT THE AREA SUNDAY NIGHT.
.LONG TERM...(MONDAY THROUGH FRIDAY)
ISSUED AT 330 PM MST FRI FEB 14 2014
LIKE YESTERDAY...FORECAST CHALLENGES WILL FOCUS ON WINDS...PRECIPITATION
AND TEMPERATURES. THE 12Z NUMERICAL MODEL GUIDANCE CONTINUES TO DEPICT
A PROGRESSIVE ZONAL FLOW ALOFT THROUGH MIDWEEK...FOLLOWED BY A MORE
AMPLIFIED WESTERN CONUS TROUGH/EASTERN CONUS RIDGE BY WEEK`S END.
BOTH MONDAY AND TUESDAY WILL BE BETWEEN PACIFIC WEATHER SYSTEMS WITH
DRY...WINDY AND MILD CONDITIONS WITH SURFACE HIGH PRESSURE OVER
COLORADO AND LEE TROUGH OVER THE HIGH PLAINS. THE CRAIG TO CASPER
700/850MB GRADIENTS WILL RANGE BETWEEN 55 AND 65M. 700MB WINDS
WILL LIKEWISE PEAK BETWEEN 55 AND 65KT IN THE VICINITY OF THE
LARAMIE RANGE. THE POTENTIAL FOR HIGH WIND EVENT FROM MONDAY
AFTERNOON THROUGH TUESDAY FOR WIND PRONE AREAS OF SOUTHEAST WY IS
LOOKING BETTER WITH TODAY`S MODEL RUN. TEMPERATURES WILL AVERAGE
10 TO 15 DEGREES ABOVE SEASONAL NORMALS WITH HIGHS IN THE 40S AND
50S LOWER ELEVATIONS WITH 30S FOR THE HIGHER TERRAIN.
ABUNDANT PACIFIC MOISTURE ARRIVES WEDNESDAY WITH PRECIPITATION (LOW
ELEVATION RAIN AND HIGH ELEVATION SNOW) DEVELOPING FROM THE LARAMIE
RANGE WESTWARD. DOWNSLOPE LOW LEVEL FLOW WILL LIMIT THE COVERAGE OF
PRECIPITATION ACROSS THE HIGH PLAINS WEDNESDAY NIGHT. IT WILL TURN
COOLER FOR AREAS OUT WEST BEHIND THE PACIFIC FRONT WITH 20S AND
30S... WHILE IT REMAINS MILD EAST WITH 40S AND 50S. WITH HIGHER
SNOW LEVELS...SNOW ACCUMULATIONS WILL BE LIGHT. CROSS MOUNTAIN FLOW
REMAINS HIGH FOR WINDY CONDITIONS FOR WIND PRONE AREAS OF SOUTHEAST
WY.
THURSDAY WILL BE BETWEEN PACIFIC SYSTEMS ONCE AGAIN WITH MAINLY
DRY CONDITIONS EXCEPT FOR THE MOUNTAINS WHERE SOME OROGRAPHIC SNOW
SHOWERS WILL LINGER. IT WILL BE COOLER THURSDAY WITH HIGHS CLOSER TO
SEASONAL NORMALS. PRESSURE GRADIENT REMAINS TIGHT WITH THE APPROACH
OF THE NEXT PACIFIC COLD FRONT SO GUSTY WESTERLY WINDS WILL CONTINUE.
TROUGH DEEPENS OVER THE ROCKIES FRIDAY. COLD FRONT WILL BE THROUGH THE
CWA BY FRIDAY MORNING WITH STRONG COLD AIR ADVECTION AND MORE WIDESPREAD
POST-FRONTAL SNOW. PRESSURE GRADIENT RELAXES WITH BRISK WEST TO NORTHWEST
WINDS. BELOW SEASONAL NORMAL TEMPERATURES WITH HIGHS IN THE 20S AND
30S VALLEYS AND HIGH PLAINS AND TEENS FOR THE MOUNTAINS.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY EVENING)
ISSUED AT 1035 PM MST FRI FEB 14 2014
STILL SOME CONCERNS FOR LOWERING FLIGHT CONDITIONS AS A COLD FRONT
SAGS INTO THE AREA FROM THE NORTHWEST. TIMING ON THE FRONT LOOKS
TO BE AROUND THE 12Z TIME FRAME WITH SNOW DEVELOPING OVER THE
LARAMIE RANGE AND POSSIBLY OUT BY LARAMIE AT THAT TIME. OF
NOTE...THE LATEST HRRR FORECAST KEEPS THE PANHANDLE VFR THROUGH
12Z...SO CONFIDENCE IS SOMEWHAT HIGH THAT OUR AIRPORTS OUT THAT
WAY WILL BE FINE.
&&
.FIRE WEATHER...
ISSUED AT 219 PM MST FRI FEB 14 2014
MINIMAL FIRE WEATHER CONCERNS THROUGH NEXT WEEK. MINIMUM AFTERNOON
HUMIDITIES WILL FALL TO AROUND 20 TO 30 PERCENT BY SUNDAY WITH GUSTY
WINDS ACROSS THE HIGH PLAINS. PERIODS OF RAIN AND SNOW ARE
EXPECTED FURTHER NORTH TONIGHT AND AGAIN SUNDAY NIGHT...MAINLY NORTH
OF THE I80 CORRIDOR.
&&
.CYS WATCHES/WARNINGS/ADVISORIES...
WY...HIGH WIND WARNING UNTIL NOON MST SATURDAY FOR WYZ106-110-114-116-
117.
HIGH WIND WARNING UNTIL 5 AM MST SATURDAY FOR WYZ104-109-115.
NE...NONE.
&&
$$
SHORT TERM...TJT
LONG TERM...JAMSKI
AVIATION...CLAYCOMB
FIRE WEATHER...TJT
AREA FORECAST DISCUSSION
NWS MOUNT HOLLY NJ
622 AM EST SAT FEB 15 2014
.SYNOPSIS...
THE LATEST LOW PRESSURE SYSTEM WILL QUICKLY SLIDE EAST OFF THE COAST
TODAY...BUT NOT BEFORE IT BRINGS ANOTHER ROUND OF SNOW TO THE
REGION. HIGH PRESSURE WILL THEN BE THE DOMINANT FEATURE IN THE
REGIONAL WEATHER PATTERN THROUGH MONDAY...FOLLOWED BY FAST MOVING
BUT RELATIVELY WEAK FRONTAL SYSTEMS ON TUESDAY AND WEDNESDAY. A
STRONGER WARM FRONT AND ASSOCIATED LOW PRESSURE WILL AFFECT THE AREA
THURSDAY NIGHT INTO FRIDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
AN AREA OF LOW PRESSURE WILL MOVE ACRS NC THIS MRNG THEN NEWD OFF
THE ATLC CST. IT WILL RAPIDLY INTENSIFY WELL OFF THE CST AS IT
MOVS TWD THE CANADIAN MARITIMES BY SUN MRNG. AS THE LOW MOVES ON
BY, IT WILL BRING SOME PRECIP WITH IT.
LATEST RADAR SHOWED SOME SNOW ACRS WRN SECTIONS OF THE AREA ALREADY
THIS MRNG WITH BOTH KRDG AND KABE REPORTING SNOW. THE GUID IS
HAVING SOME DISAGREEMENT AS TO HOW FAST IT PUSHES EAST, WITH MOST IN
AGREEMENT THAT IT DOESN`T GET TO THE I-95 CORRIDOR UNTIL AT LEAST
AROUND DAYBREAK.
THERE ARE ALSO SOME QUESTIONS AS TO HOW MUCH QPF WE WILL SEE, WITH
THE HRRR AND ECMWF ON THE LOWER END AND THE SREF AND GFS A BIT
HIGHER. FROM THE I-95 CORRIDOR S AND E, THERE IS ALSO THE QUESTION
OF TEMPS AND PRECIP TYPE AS TEMPS ARE FCST TO GET ABV FREEZING DURG
THE DAY SO THERE SHOULD AT LEAST BE SOME MIXING AND CHANGING DURG
THE DAY TODAY.
THEREFORE, WILL BE KEEPING ACCUMS ABOUT THE SAME AND NOT BE MAKING
ANY CHANGES TO THE ADVYS. HOWEVER, IT SEEMS THAT THIS WINTER
VIRTUALLY EVERY SYS HAS OVERPERFORMED, SO IF THIS ONE DOES, THERE
MAY NEED TO BE A SEWD MVMT OF ADVYS, BUT CERTAINLY THIS IS A MORE
MARGINAL EVENT DUE TO TIME OF YEAR, TIME OF DAY AND TEMPS.
TEMPS ARE A BIT WARMER THAN ORIGINALLY FCST ACRS THE ERN SHORE AND
SRN DEL SO HAVE CHANGED PRECIP TYPE TO RAIN OR MIX IN THESE AREAS
FOR NOW. ALSO PUSHED BACK ONSET TIME OF PRECIP S AND E OF THE I-95
CORRIDOR. THE HRRR SEEMS TO BE HANDLING THIS QUITE WELL SO WENT
MORE IN LINE WITH ITS FCST.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 AM SUNDAY/...
PRECIP SHOULD BE ALL BUT OVER OR COMING TO AN END AT THE START OF
THE PD AND HIGH PRES WILL BUILD IN FROM THE W. THE PGRAD BETWEEN
THE AFOREMENTIONED HIGH AND THE INTENSIFYING LOW WILL BE QUITE
STRONG AND EXPECT GUSTY NW WIND TO DEVELOP. THIS WILL MAKE A COLD
NIGHT FEEL EVEN COLDER. WIND COULD GUST UPWARDS OF 25 TO 30 MPH AND
THE SKY WILL GRADUALLY CLEAR.
&&
.LONG TERM /SUNDAY THROUGH FRIDAY/...
IN THE WAKE OF TODAY`S LOW...HIGH PRESSURE AT THE SURFACE AND
RIDGING ALOFT WILL START TO BUILD IN. THERE IS ONE EXCEPTION ON
SUNDAY AFTERNOON...BOTH THE GFS AND NAM SHOW WEAK POSITIVE PRESSURE
ADVECTION AT THE 1.5PV LEVEL ACROSS E CENTRAL PA INTO NW NJ. THIS
LOOKS TO BE ASSOCIATED WITH A SMALL EMBEDDED UPPER LEVEL TROUGH. THE
WINDOW OF LIFT IS LIMITED TO JUST A FEW HOURS SUNDAY AFTERNOON...AND
WITH NORTHERLY FLOW...THERE IS LIMITED MOISTURE. STILL THERE IS A
BRIEF WINDOW OF OPPORTUNITY FOR SOME SNOW. DUE TO THE BRIEF WINDOW
OF OPPORTUNITY...DO NOT ANTICIPATE MUCH ADDITIONAL ACCUMULATION AT
THIS TIME.
THE CONTINENTAL POLAR AIR MASS REMAINS IN PLACE THROUGH AT LEAST
MONDAY...LIMITING...AT LEAST FOR NOW...SIGNIFICANT MELTING OF THE
SNOWPACK OVER THE REGION. CONSIDERING THIS...HAVE FOLLOWED THE
TREND OF PREVIOUS SHIFTS IN UNDERCUTTING GUIDANCE FOR MAX
TEMPERATURES DUE TO THE SNOWPACK FOR MOST OF THE REGION.
THE FIRST SIGN OF THE WARMER PATTERN SHIFT COMES WITH THE SYSTEM
MONDAY NIGHT INTO TUESDAY. THOUGH ANY PRECIPITATION WITH THIS
SYSTEM SHOULD INITIALLY BEGIN AS SNOW...A WEAK WARM FRONT SHOULD
LIFT AS FAR NORTH AS THE DELMARVA AREA...SO AT LEAST THE SOUTHERN
HALF OF OUR REGION MAY SEE A BRIEF CHANGE OVER TO RAIN BEFORE THE
PRECIPITATION ENDS TUESDAY AFTERNOON.
THEN COMES THE REALLY EXCITING PART OF THE FORECAST...WE SHOULD
SEE A PAIR OF WARM FRONTS...ONE ON WEDNESDAY...ANOTHER ONE
THURSDAY...BRINGING WARMER CONDITIONS TO THE REGION. IN BOTH
CASES...MOST OF THE PRECIPITATION WE EXPECT WITH THESE SYSTEMS
SHOULD BE IN THE WARM SECTOR...MEANING WE WOULD EXPECT TO SEE
MOSTLY RAIN. GIVEN THE HIGH LIQUID CONTENT OF THE SNOW
PACK...STILL UNDERCUT GUIDANCE MAX T FOR THE DELAWARE RIVER VALLEY
AND LOCATIONS NORTHWEST OF THERE ON WEDNESDAY...AND UNDERCUT
GUIDANCE IN THE POCONOS AND THE LEHIGH VALLEY...WHERE CURRENT SNOW
DEPTHS ARE ABOVE 20 INCHES...THROUGH THE END OF THE WEEK.
&&
.AVIATION /12Z SATURDAY THROUGH WEDNESDAY/...
LTST RADAR IMAGERY SHOWED A BAND OF SNOW OVER THE NRN AND WRN
AREAS. THIS SNOW DROPPED KRDG DOWN FAIRLY QUICKLY AS IT MOVED BY
BUT THEY HAVE RETURNED TO VFR CIGS BUT MVFR VSBY NOW THAT IT HAS
PASSED. KABE REMAINS MVFR AND SOME IFR IS NOT OUT OF THE QUESTION
UNTIL IT MOVES BY THEM. ALL OTHER SITES REMAIN VFR. IT IS EXPECTED
THEY WILL REMAIN VFR UNTIL IMPACTED BY PRECIP LATER THIS MRNG. ALG
THE I-95 CORRIDOR, THAT SHUD BE AROUND DAYBREAK.
THE LATEST GUID INDICATES THAT ONCE A SITE GOES DOWN THEY SHUD STAY
DOWN, BUT BASED UPON WHAT IS BEING OBSERVED SO FAR TONIGHT,
CONFIDENCE IS LOW ON THAT. THERE WILL CERTAINLY BE PERIODS OF
REDUCED CIGS/VSBYS BUT ITS PSBL THERE COULD BE SOME BREAKS AS WELL.
FROM THE I-95 CORRIDOR S AND E PRECIP COULD MIX WITH OR CHANGE TO
RAIN AS WELL DURING THE DAY AS TEMPS CLIMB ABV FREEZING.
BY EVENING, MOST IF NOT ALL OF THE PRECIP IS OVER AND CONDS SHUD
RETURN TO VFR. THEN THE NEXT ISSUE IS A STRONG AND GUSTY NW WIND
WHICH WILL DEVELOP THE WIND CUD GUST TO 30 KTS OVERNIGHT.
OUTLOOK...
SUNDAY...GENERALLY VFR. A FEW LIGHT SHSN WILL BE POSSIBLE MAINLY
NW OF KABE.
MONDAY...GENERALLY VFR THROUGH THE DAY.
MONDAY NIGHT AND TUESDAY...MVFR AND OCCASIONAL IFR IN SN THROUGH
TUESDAY MORNING. PRECIPITATION MAY BRIEFLY CHANGE TO RA IN THE
AFTERNOON BEFORE ENDING...WITH A RETURN TO VFR CONDITIONS.
WEDNESDAY...GENERALLY VFR WITH SOME MVFR CEILINGS POSSIBLE IN RA
DURING THE DAY WEDNESDAY.
&&
.MARINE...
AN AREA OF LOW PRESSURE WILL MOVE ACRS NC THIS MRNG THEN OFF THE
ATLC CST AS IT MOVES NEWD TWD THE CAN MARITIMES BY SUN MRNG. THE
LOW WILL RAPIDLY INTENSIFY AS IT MOVES TWD CANADA. THE PRESSURE
GRADIENT BETWEEN THIS LOW AND HIGH PRESSURE THAT MOVES IN BEHIND IT
WILL BECOME QUITE STRONG AND A GUSTY NW WIND IS EXPECTED TO DEVELOP
BY LATE AFTN. THEREFORE, THE GALE WATCH IS BEING REPLACED BY A GALE
WRNG FOR ALL MARINE ZONES AND IT WILL BE IN EFFECT THRU 11Z.
OUTLOOK...
SUNDAY...SCA CONDITIONS EXPECTED FOR MUCH OF THE DAY...DECREASING
BELOW SCA BY LATE SUNDAY NIGHT.
MONDAY THROUGH WEDNESDAY...SUB-SCA CONDITIONS EXPECTED.
&&
.PHI WATCHES/WARNINGS/ADVISORIES...
PA...WINTER WEATHER ADVISORY UNTIL 6 PM EST THIS EVENING FOR PAZ054-
055-060>062-101>106.
NJ...WINTER WEATHER ADVISORY UNTIL 6 PM EST THIS EVENING FOR NJZ001-
007>009.
DE...NONE.
MD...WINTER WEATHER ADVISORY UNTIL 6 PM EST THIS EVENING FOR MDZ008.
MARINE...GALE WARNING FROM 4 PM THIS AFTERNOON TO 6 AM EST SUNDAY FOR
ANZ430-431-450>455.
&&
$$
SYNOPSIS...JOHNSON
NEAR TERM...NIERENBERG
SHORT TERM...NIERENBERG
LONG TERM...JOHNSON
AVIATION...JOHNSON/NIERENBERG
MARINE...JOHNSON/NIERENBERG
AREA FORECAST DISCUSSION
NWS COLUMBIA SC
638 AM EST SAT FEB 15 2014
.SYNOPSIS...
A FRONT WILL CROSS THE REGION LATE TONIGHT...WHICH WILL BRING A
PERIOD OF SHOWERS FOLLOWED BY WINDY CONDITIONS SATURDAY. FAIR
WEATHER EXPECTED SUNDAY AND MONDAY. A WEAK FRONT WILL APPROACH THE
REGION TUESDAY. A WARMING TREND IS EXPECTED NEXT WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
COLD FRONT MOVING EAST OF THE MIDLANDS AT 11Z. AREA OF SHOWERS
MOVING TO THE NORTHEAST OF CAE. SHOWERS IN THE NORTH MIDLANDS/PEE
DEE EARLY THEN DECREASING CLOUDINESS THIS MORNING AS UPPER LEVEL
TROUGH MOVES EAST AND SURFACE LOW MOVES NORTHEAST OFFSHORE NORTH
CAROLINA. WINDS BEGINNING TO INCREASE UPSTREAM ACROSS GEORGIA WITH
GUSTS 20 TO 30 KNOTS. WINDY CONDITIONS EXPECTED TO INCREASE
ACROSS THE AREA AS SURFACE PRESSURE GRADIENT TIGHTENS.
WEAK COLD ADVECTION BUT WITH CLEARING SKIES AND PLENTY OF SUN
TEMPERATURES WILL ONLY BE A CATEGORY OR SO COOLER THAN TODAY. THE
WINDS WILL BE THE MAIN FOCUS WITH A TIGHT PRESSURE GRADIENT
BETWEEN THE DEEPENING LOW OFFSHORE AND HIGH PRESSURE BUILDING IN
FROM THE WEST. LAKE WIND ADVISORY FROM 7 AM THROUGH 5 PM TO
ACCOUNT FOR THE STRONG WINDS. THE POTENTIAL FOR A WIND ADVISORY
EXISTS AS THE UPPER SYSTEM BECOMES A BIT NEGATIVELY TILTED AND
THERE WILL BE SOME DOWNSLOPING FLOW. LATEST LAMP AND RAP GUIDANCE
SUGGESTS WINDS GUSTS AROUND 30 KTS...SO WILL HOLD OFF ON WIND
ADVISORY.
THE SIGNIFICANT WINDS ON MAY IMPEDE THE ICE STORM CLEAN UP IN THE
SOUTHERN MIDLANDS AND CENTRAL SAVANNAH RIVER AREA. HIGH
TEMPERATURES SHOULD RANGE FROM THE UPPER 40S TO AROUND 50 NORTHERN
MIDLANDS TO MID 50S SOUTHEASTERN MIDLANDS.
&&
.SHORT TERM /SUNDAY THROUGH MONDAY/...
SOME CLOUDS LATE TONIGHT AND EARLY SUNDAY ASSOCIATED WITH WEAK
TROUGH BUT AIR MASS WILL BE DRY. GUIDANCE TEMPERATURES MAINLY IN
THE MID TO UPPER 20S...MAY BE TOO LOW DUE TO CLOUDS. TEMPERATURES
MODERATING ON SUNDAY WITH HIGH PRESSURE ACROSS THE AREA AND
DOWNSLOPE FLOW. MAX TEMPERATURES IN THE LOW TO MID 50S NORTH TO
THE LOW 60S CSRA.
&&
.LONG TERM /MONDAY NIGHT THROUGH FRIDAY/...
UPPER LEVEL FLOW WILL BECOME ZONAL THROUGH MID WEEK...WITH UPPER
GROGGINESS DEVELOPING TO OUR WEST BY LATE WEEK. A FRONT WILL
APPROACH THE REGION TUESDAY...THEN STALL AND LIFT NORTH AS A WARM
FRONT THROUGH LATE WEEK...PROVIDING A SLIGHT CHANCE OF SHOWERS.
UPPER HEIGHT RISES OVER THE SE CONUS...AND S TO SW LOW LEVEL FLOW
AHEAD OF ANOTHER APPROACHING FRONT...WILL PROVIDE WARM
TEMPERATURES MID TO LATE WEEK.
&&
.AVIATION /12Z SATURDAY THROUGH WEDNESDAY/...
MVFR CONDITIONS AT THE TAF SITES IMPROVING TO VFR FROM 13Z THROUGH
THE END OF THE PERIOD.
COLD FRONT QUICKLY MOVING EAST OF THE TAF SITES AND WILL MOVE
OFFSHORE OVER THE NEXT COUPLE OF HOURS. WINDS HAVE BEGUN TO
INCREASE AND BECOME GUSTY AS THE PRESSURE GRADIENT TIGHTENS BEHIND
THE FRONT. BY 13Z WINDS WILL HAVE BECOME WESTERLY AROUND 18 KNOTS
WITH GUSTS TO 28 KNOTS...THEN SLOWLY VEER TO NORTHWESTERLY AND
SUBSIDE THROUGH THE AFTERNOON HOURS WITH GUSTS CEASING BY 23Z.
FROM 16/02Z THROUGH THE END OF THE PERIOD WINDS WILL BE LIGHT AND
VARIABLE. WITH DRIER AIR MOVING INTO THE AREA CLOUDS WILL ALSO
DIMINISH THROUGH THE AFTERNOON.
EXTENDED AVIATION OUTLOOK...NO SIGNIFICANT IMPACTS TO AVIATION
EXPECTED SUNDAY MORNING THROUGH WEDNESDAY.
&&
.CAE WATCHES/WARNINGS/ADVISORIES...
SC...LAKE WIND ADVISORY UNTIL 5 PM EST THIS AFTERNOON FOR SCZ015-
016-018-020>022-025>031-035>038-041.
GA...LAKE WIND ADVISORY UNTIL 5 PM EST THIS AFTERNOON FOR GAZ040-
063>065-077.
&&
$$
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
535 AM CST Sat Feb 15 2014
...Updated for the aviation discussion...
.SHORT TERM...(Today and tonight)
ISSUED AT 123 AM CST SAT FEB 15 2014
Today:
Pretty interesting temperature forecast for today. A lee low with an
associated warm front will clip the southern part of the forecast area
of responsibility during the afternoon. Here, very warm 850 hPa temperatures
of 18-20C & downslope plume will be pretty close to the Colorado and
Oklahoma state borders. The tail end of the HRRR is also latching on
to this in the reflection of a sfc thermal gradient across far southwest
Kansas. Think that mid 70sF will be a distinct possibility by Elkhart.
Elsewhere, an approaching cold front will move across portions of southwest
Kansas today. As seen with yesterday, there will be considerable mixing
and think that the NAM is under-doing this and the low level thermal
gradient. Will call for a gradient of low 60sF across much of the forecast
area with mid 60sF to low 70sF across far western Kansas.
Tonight:
By this evening, high pressure will ridge across the outlook area with
fairly light winds. There will be weak upslope flow across western
Kansas with weak warm air advection in the low levels on the backside
of the departing high. The NAM/NSSL WRF/SREF probabilities show fog
potential for Sunday morning. Not very confident in spatial arrangement
of fog, but have added it in the wx grids in case these three models
are correct. Future shifts can adjust as necessary. Dewpoints won`t
be very high, but there could be a radiational fog environment with
an inversion and light sfc winds. Overnight minimums will be higher
as fog and mid to high level cloud cover lingers. Saw no reason to deviate
from previous forecast, which is widespread low 30s for lows.
.LONG TERM...(Sunday through Friday)
ISSUED AT 314 AM CST SAT FEB 15 2014
On Sunday, there will be a nearly zonal flow over the plains, with a
cold front approaching from the north. It should be mostly sunny
with mainly high cirrus clouds passing overhead. Winds will be from
the southwest and the pressure gradient will tighten up in the
afternoon as the cold front encroaches. Winds should start out
from the southwest at 5 to 15 mph in the morning, but increase
from the southwest at 15 to 20 mph with gusts to near 30 mph in
the afternoon. It should warm up nicely into the upper 50s to
lower 60s, but the winds will still be noticeable. Sunday night
could be windier than Sunday, as the cold front moves through.
South winds will shift to the northwest at 15 to 30 mph, gusting
as high as 40 mph. A wind advisory may be needed for parts of
Sunday night and Monday morning. Those strong winds will continue
into Monday morning, bringing the same 20 mph to 30 mph gusting to
40 mph range to that area east of a Scott City to Meade line. By
late Monday, winds should be from the west at around 10 mph. The
cold front will bring down max temps somewhat, into the middle
50s.
Tuesday will respond to a wind shift back to the southwest, with
mostly sunny skies and maximum temperatures in the middle to upper 60s.
A zonal flow will return aloft Tuesday into Wednesday. Wednesday
should be the warmest day overall, with lower 60s expected north of
I-70, and maxes around 70F along the Oklahoma border. A large upper
level trough will approach from the west Wednesday night, bringing
first a slight chance for rain to our western CWA, basically west of
a Hays to Liberal line, and then a chance for light snow after
midnight Wednesday night. By Thursday morning, there will be a cold
front dragging through southwest Kansas, the precip may be either
rain or snow Thursday morning. By afternoon, the lower layers
should warm up enough to change any precipitation back to rain,
east of a Scott City to Garden City to near Liberal line. Right
now, I do not think anyone will get more than light rain or light
snow.
We will go into a zonal flow aloft by Friday, and then to a
southwest upper level flow by Saturday. Friday will be a moderating
day with highs in the mid 50s to lower 60s, then clouds and shallow
cold air spilling south from the northern plains will dip maximum temperatures
back into the lower to middle 40s by Saturday, which will be closer
to climatological highs.
&&
.AVIATION...(For the 12Z TAFS through 12Z Sunday morning)
ISSUED AT 530 AM CST SAT FEB 15 2014
The first concern is wind shear this morning. There is a south-southwest
low level jet, just off the surface, at around 2000 ft. It is
blowing nearly 40 knots at that level, while at the surface winds
are southerly at only 13 knots. As that jet moves off to the east
around 16z, the localized wind shear will diminish. Cirrus clouds
are increasing, and cigs in the bkn200-250 range should develop by
15 to 16Z. Later this afternoon, the cirrus deck will scatter out,
a cold front will move through, and winds will shift to the north
at around 10kts by 21z.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 62 31 61 39 / 0 0 0 0
GCK 63 32 62 39 / 0 0 0 0
EHA 76 32 69 41 / 0 0 0 0
LBL 69 32 66 41 / 0 0 0 0
HYS 61 30 57 36 / 0 0 0 0
P28 61 32 59 40 / 0 0 0 0
&&
.DDC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...Sugden
LONG TERM...Burke
AVIATION...Burke
AREA FORECAST DISCUSSION
NWS TWIN CITIES/CHANHASSEN MN
532 AM CST SAT FEB 15 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 408 AM CST SAT FEB 15 2014
REGIONAL RADAR THIS MORNING HAS TWO AREAS OF ENHANCED REFLECTIVITY
ASSOCIATED WITH A STRONG JET STREAK MOVING SE ACROSS THE NORTHERN
PLAINS. ACROSS ND/SD...THE REFLECTIVITY PATTERN IS MORE DISORGANIZED
AND IS WEAKER COMPARED TO ANOTHER AREA IN NEBRASKA WHICH HAS A
BETTER ORIENTATION OF THE 92-70H FRONTOGENETIC REGIME. IN
ADDITION...ACROSS THE UPPER MIDWEST...MOISTURE IS LACKING IN THE
DENDRITIC GROWTH ZONE. ALTHOUGH THE LATEST 07Z RAP HAS INCREASED THE
MOISTURE IN THIS GROWTH ZONE BY 12-15Z IN WESTERN MN...AM NOT
TOTALLY CONVINCED BOTH THE MOISTURE AND LIFT WILL ORGANIZE ENOUGH TO
WARRANT CATEGORICAL POPS NORTH OF THE MN RIVER VALLEY. AM LEANING
TOWARD THE CONTINUED HIGHER POPS ALONG THE IA/MN BORDER BY
15-18Z...WITH LOWER CONFIDENCE FURTHER TO THE N/NE. WOULD LIKE TO
SEE MORE -SN OBS IN SD/ND BEFORE CONFIDENCE INCREASES FOR SNOWFALL
TOTALS GREATER THAN A LIGHT DUSTING NORTH OF THE MN RIVER VALLEY.
HOWEVER...DUE TO THE STRENGTH OF THE FORCING BY 15-18Z ALONG THE
IA/MN...THERE COULD BE A QUICK 1-2 INCHES OF SNOW BEFORE IT TAPERS
OFF BY EARLY AFTN. ELSEWHERE...CONFIDENCE IS LOW FOR ANYTHING MORE
THAN ONE HALF INCH. TEMPERATURES MAY REACH THE LOWER 30S ALONG THE
LEE OF THE BUFFALO RIDGE TODAY AS UPSTREAM OBS IN SW ND/NW SD HAVE
30S ALREADY THIS MORNING. THE MEAN FLOW IN THE BOUNDARY LAYER WILL
HELP ADVECT THESE TEMPS ACROSS SD...AND INTO SW MN LATER TODAY.
ELSEWHERE...20S WILL BE COMMON. NO CHGS ON THE FORECAST TONIGHT AS
CLEARING TAKES PLACE IN THE WAKE OF THIS SYSTEM.
.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 408 AM CST SAT FEB 15 2014
SEMI-ZONAL FLOW BECOMES ESTABLISHED BY 18Z SUNDAY...AND THE NEXT
SYSTEM RACES TOWARD THE AREA. THE ATTENDANT PV REFLECTION IS A BIT
DISJOINTED...WITH ONE POCKET PASSING ACROSS NORTHERN MN AND THE
OTHER PASSING ACROSS IOWA. REGARDLESS...SHOULD SEE A DECENT PERIOD
OF PRECIPITATION ON SUNDAY NIGHT AND MONDAY AS THE TROUGH TAKES ON
A SLIGHT NEGATIVE TILT AND A HEALTHY BURST OF ISENTROPIC UPGLIDE
ARRIVES /PER THE 280K-295K SURFACES/. THERMAL PROFILES ARE WARMER
WITH THIS SYSTEM...AND 0-6KM SFC WET BULB TEMPS ILLUSTRATE THE
POTENTIAL FOR LIGHT FREEZING DRIZZLE OR SLEET ACROSS
SOUTHWEST/SOUTH CENTRAL MN ON SUNDAY NIGHT BETWEEN 03Z AND
12Z...WITH AREAS OF FREEZING DRIZZLE ACROSS THE SOUTHEAST ON
MONDAY AFTERNOON AT THE END OF THE EVENT. SNOW ACCUMULATIONS DURING
THE 24 HOUR PERIOD /00Z MON-00Z TUE/ COULD APPROACH WARNING CRITERIA /6
INCHES/ IN OUR NORTHERN WEST CENTRAL WI COUNTIES...TAPERING TO
AROUND 3 INCHES IN THE TWIN CITIES...DOWN TO AROUND 1 INCH IN THE
SOUTHWEST WHERE THE POTENTIAL FOR MIXED PRECIP EXISTS.
TUESDAY THROUGH WEDNESDAY THEN LOOK TO BE BENIGN WEATHER-WISE IN
THE WAKE OF THE SYSTEM...WITH THE MAIN HIGHLIGHT BEING WARMER
TEMPERATURES WITH HIGHS IN THE MID 30S TO POSSIBLY EVEN LOWER 40S.
ATTENTION AT THE END OF THE WORK WEEK WILL BE FOCUSED ON THE
POTENTIAL FOR A NOTABLE SYSTEM BRINGING SIGNIFICANT SNOWFALL
ACCUMULATIONS TO THE REGION. MODEL SOLUTIONS ARE ADMITTEDLY ALL
OVER THE MAP WITH RESPECT TO THE SYNOPTIC DETAILS...BUT BOTH ECMWF
AND GFS MODELS HAVE BEEN INSISTENT ON THE ARRIVAL OF AT LEAST ONE
SUBSTANTIAL MID LATITUDE CYCLONE TOWARD NEXT WEEKEND. STAY TUNED...
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SUNDAY MORNING)
ISSUED AT 511 AM CST SAT FEB 15 2014
MAIN AVIATION CONCERN IS TIMING OF -SN ONCE IT DEVELOPS ACROSS
WESTERN MN...AND SHIFTS EASTWARD ACROSS SOUTHERN MN DURING THE
LATE MORNING/EARLY AFTN. AFT THE -SN ENDS...MVFR/IFR CIGS WILL BE
POSSIBLE.
REGIONAL RADAR HAD DEPICTED AN AREA OF -SN ACROSS SOUTHERN
ND...STARTING TO MOVE TO THE E/SE ACROSS NE SD AS OF 515 AM.
ALTHOUGH VFR CIGS REMAINED ACROSS ND UNDER THE HIGHER
REFLECTIVITY...MODELS CONTINUED TO SATURATE THE ATMOSPHERE BY 15Z
ACROSS SW/WC MN WHICH -SN SHOULD BEGIN. BASED ON TIMING OF OUR
LOCAL MODEL...-SN SHOULD BEGIN NEAR KRWF BY 14Z...KAXN BY 15Z AND
AT KSTC BY 17Z. THERE SHOULD BE A PERIOD OF IFR/MVFR VSBYS IN -SN.
HOWEVER...IT DOESN/T LOOK TO BE HEAVY ENOUGH FOR VSBYS LESS THAN
1SM. BY 21Z...MOST OF THE -SN SHOULD BE EAST OF MPX TAF AREA...BUT
MVFR CIGS SHOULD CONTINUE IN THE WAKE OF THE PRECIPITATION UNTIL
AT LEAST 3-6Z. CONFIDENCE ON -SN DEVELOPING THIS MORNING IS
HIGH...BUT LOW ON THE INTENSITY AND HOW LONG IT WILL LAST. WINDS
WILL START FROM THE S/SSE ARND 8-12 KTS...BECOME LIGHT S/SW THIS
AFTN...THEN NW OVERNIGHT.
KMSP...
SE WNDS WILL INCREASE ABV 6 KTS BY 14-15Z. VFR CIGS WILL DECREASE
TO MVFR ONCE THE -SN STARTS ARND 1630-17Z...WITH A PERIOD OF IFR
VBSYS IN -SN. THE MVFR CIGS /LOWER THAN 1.7K/ SHOULD REMAIN AT MSP
AFT THE -SN ENDS...BUT SLOWLY LIFT DURING THE EVENING. VFR CONDS
ARE POSSIBLE BY 12Z/16. CONFIDENCE ON -SN BY 18Z IS HIGH...BUT LOW
CONFIDENCE ON VSBY/CIGS ONCE THE -SN DEVELOPS. WINDS WILL REMAIN
FROM THE SE ARND 8-10 KTS THRU 23Z...THEN DECREASE AND BECOME MORE
SW...THEN NW OVERNIGHT. EXPECT GUSTY WINDS DEVELOPING AFT 12Z/16.
/OUTLOOK FOR KMSP/
SUN...VFR EARLY. MVFR/IFR IN -SN LATE. LIGHT...BECMG SE 10 KTS.
MON...MVFR/IFR EARLY IN -SN. VFR BY AFTN. WIND WSW 5 KT.
TUE...VFR. WIND SW TO W 5-10 KT.
&&
.MPX WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...NONE.
&&
$$
SHORT TERM...JLT
LONG TERM...LS
AVIATION...JLT
AREA FORECAST DISCUSSION
NWS TWIN CITIES/CHANHASSEN MN
408 AM CST SAT FEB 15 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 408 AM CST SAT FEB 15 2014
REGIONAL RADAR THIS MORNING HAS TWO AREAS OF ENHANCED REFLECTIVITY
ASSOCIATED WITH A STRONG JET STREAK MOVING SE ACROSS THE NORTHERN
PLAINS. ACROSS ND/SD...THE REFLECTIVITY PATTERN IS MORE DISORGANIZED
AND IS WEAKER COMPARED TO ANOTHER AREA IN NEBRASKA WHICH HAS A
BETTER ORIENTATION OF THE 92-70H FRONTOGENETIC REGIME. IN
ADDITION...ACROSS THE UPPER MIDWEST...MOISTURE IS LACKING IN THE
DENDRITIC GROWTH ZONE. ALTHOUGH THE LATEST 07Z RAP HAS INCREASED THE
MOISTURE IN THIS GROWTH ZONE BY 12-15Z IN WESTERN MN...AM NOT
TOTALLY CONVINCED BOTH THE MOISTURE AND LIFT WILL ORGANIZE ENOUGH TO
WARRANT CATEGORICAL POPS NORTH OF THE MN RIVER VALLEY. AM LEANING
TOWARD THE CONTINUED HIGHER POPS ALONG THE IA/MN BORDER BY
15-18Z...WITH LOWER CONFIDENCE FURTHER TO THE N/NE. WOULD LIKE TO
SEE MORE -SN OBS IN SD/ND BEFORE CONFIDENCE INCREASES FOR SNOWFALL
TOTALS GREATER THAN A LIGHT DUSTING NORTH OF THE MN RIVER VALLEY.
HOWEVER...DUE TO THE STRENGTH OF THE FORCING BY 15-18Z ALONG THE
IA/MN...THERE COULD BE A QUICK 1-2 INCHES OF SNOW BEFORE IT TAPERS
OFF BY EARLY AFTN. ELSEWHERE...CONFIDENCE IS LOW FOR ANYTHING MORE
THAN ONE HALF INCH. TEMPERATURES MAY REACH THE LOWER 30S ALONG THE
LEE OF THE BUFFALO RIDGE TODAY AS UPSTREAM OBS IN SW ND/NW SD HAVE
30S ALREADY THIS MORNING. THE MEAN FLOW IN THE BOUNDARY LAYER WILL
HELP ADVECT THESE TEMPS ACROSS SD...AND INTO SW MN LATER TODAY.
ELSEWHERE...20S WILL BE COMMON. NO CHGS ON THE FORECAST TONIGHT AS
CLEARING TAKES PLACE IN THE WAKE OF THIS SYSTEM.
.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 408 AM CST SAT FEB 15 2014
SEMI-ZONAL FLOW BECOMES ESTABLISHED BY 18Z SUNDAY...AND THE NEXT
SYSTEM RACES TOWARD THE AREA. THE ATTENDANT PV REFLECTION IS A BIT
DISJOINTED...WITH ONE POCKET PASSING ACROSS NORTHERN MN AND THE
OTHER PASSING ACROSS IOWA. REGARDLESS...SHOULD SEE A DECENT PERIOD
OF PRECIPITATION ON SUNDAY NIGHT AND MONDAY AS THE TROUGH TAKES ON
A SLIGHT NEGATIVE TILT AND A HEALTHY BURST OF ISENTROPIC UPGLIDE
ARRIVES /PER THE 280K-295K SURFACES/. THERMAL PROFILES ARE WARMER
WITH THIS SYSTEM...AND 0-6KM SFC WET BULB TEMPS ILLUSTRATE THE
POTENTIAL FOR LIGHT FREEZING DRIZZLE OR SLEET ACROSS
SOUTHWEST/SOUTH CENTRAL MN ON SUNDAY NIGHT BETWEEN 03Z AND
12Z...WITH AREAS OF FREEZING DRIZZLE ACROSS THE SOUTHEAST ON
MONDAY AFTERNOON AT THE END OF THE EVENT. SNOW ACCUMULATIONS DURING
THE 24 HOUR PERIOD /00Z MON-00Z TUE/ COULD APPROACH WARNING CRITERIA /6
INCHES/ IN OUR NORTHERN WEST CENTRAL WI COUNTIES...TAPERING TO
AROUND 3 INCHES IN THE TWIN CITIES...DOWN TO AROUND 1 INCH IN THE
SOUTHWEST WHERE THE POTENTIAL FOR MIXED PRECIP EXISTS.
TUESDAY THROUGH WEDNESDAY THEN LOOK TO BE BENIGN WEATHER-WISE IN
THE WAKE OF THE SYSTEM...WITH THE MAIN HIGHLIGHT BEING WARMER
TEMPERATURES WITH HIGHS IN THE MID 30S TO POSSIBLY EVEN LOWER 40S.
ATTENTION AT THE END OF THE WORK WEEK WILL BE FOCUSED ON THE
POTENTIAL FOR A NOTABLE SYSTEM BRINGING SIGNIFICANT SNOWFALL
ACCUMULATIONS TO THE REGION. MODEL SOLUTIONS ARE ADMITTEDLY ALL
OVER THE MAP WITH RESPECT TO THE SYNOPTIC DETAILS...BUT BOTH ECMWF
AND GFS MODELS HAVE BEEN INSISTENT ON THE ARRIVAL OF AT LEAST ONE
SUBSTANTIAL MID LATITUDE CYCLONE TOWARD NEXT WEEKEND. STAY TUNED...
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT)
ISSUED AT 1146 PM CST FRI FEB 14 2014
VFR FOR THE NEXT 6-9 HOURS WITH CONDITIONS DETERIORATING QUICKLY
INTO EARLY SATURDAY AFTERNOON. CLOUDS WILL INCREASE LATE
TONIGHT...THICKENING AND LOWERING AHEAD OF A CLIPPER SYSTEM
TRACKING ALONG A LINE FROM EASTERN SOUTH DAKOTA TO SOUTHWESTERN
MINNESOTA AND NORTHEASTERN IOWA SATURDAY AFTERNOON. IFR VIS SNOW
WILL LIKELY ACCOMPANY THE SYSTEM...PARTICULARLY ALONG THE
MINNESOTA RIVER VALLEY. SNOWFALL AMOUNTS WILL RANGE FROM LESS THAN
AN INCH AT AXN AND STC TO AROUND AN INCH AT RWF/MSP/RNH/EAU.
KMSP...SKC TONIGHT...THEN CLOUDS INCREASE WITH SNOW BEGINNING LATE
MORNING. INTENSITY WILL INCREASE QUICKLY WITH 1-2SM LIKELY FOR
A FEW HOURS BEFORE TAPERING OFF IN THE MID TO LATE AFTERNOON.
SNOW RATES SHOULD REMAIN 1/2 INCH PER HOUR OR LESS.
/OUTLOOK FOR KMSP/
SUN...MVFR CIGS POSSIBLE WITH SN LIKELY LATE SUN NIGHT.
LIGHT/VARIABLE WIND BECOMING SE 10-15 KTS.
MON...MVFR CONDITIONS WITH -SN LIKELY EARLY. WIND SW 10 KT.
TUE...VFR LIKELY. WIND SW 5-10 KT.
&&
.MPX WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...NONE.
&&
$$
SHORT TERM...JLT
LONG TERM...LS
AVIATION...BORGHOFF
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 CHEYENNE WY
416 AM MST SAT FEB 15 2014
.SHORT TERM...(TODAY THROUGH MONDAY NIGHT)
ISSUED AT 400 AM MST SAT FEB 15 2014
WIND HAS INCREASED SINCE MIDNIGHT OVER MUCH OF THE LOWER
ELEVATIONS IN SOUTHEAST WYOMING. LAR HAD A GUST TO 52 KTS AND CYS
A GUST TO 47 KTS. THE WINDS HAVE INCREASED JUST AS THE GFS SHOWED
AN AXIS OF 60 KT 700MB WINDS STRETCHING FROM RAWLINS TO CHEYENNE.
WILL KEEP THE HIGH WIND WARNINGS GOING AS IS...ALTHOUGH THE WINDS
SHOULD DECREASE AFTER SUNRISE AS PRESSURE RISES OCCUR OVER THE
PLAINS. A WEAK FRONT IS PROGGED TO PUSH SOUTHWARD TO THE EAST OF
THE LARAMIE RANGE THROUGH THE MORNING. THERE IS ENOUGH LLVL
CONVERGENCE AND WEAK MIDLEVEL FRONTOGENESIS TO GENERATE LIGHT QPF
BEHIND THE SFC BOUNDARY. TEMPERATURES IN THE MID-TO-UPPER 30S
WOULD SUPPORT A MIX OF RAIN AND SNOW. SFC WINDS CLOSER TO THE
COLORADO BORDER NEVER REALLY GO NORTHERLY...BUT STAY WEST-
NORTHWESTERLY AND DOWNSLOPE WHICH WILL KEEP PRECIP CHANCES LOWER
IN LARAMIE AND ALBANY COUNTIES. MOIST 700-500MB NORTHWESTERLY FLOW
WILL KEEP OROGRAPHIC SNOWS GOING IN THE SIERRA MADRE AND SNOWY
RANGES THROUGH LATE MORNING...HOWEVER ONLY LIGHT ACCUMULATIONS (AN
ADDITIONAL 1-3 INCHES) IS EXPECTED.
SHORTWAVE RIDGE MOVES OVER THE REGION TONIGHT AND WINDS ACROSS
SOUTHEAST WYOMING WILL DECREASE OVER THE PERIOD FROM LATE THIS
MORNING THROUGH TONIGHT. THE BREAK IN THE WIND IS REALLY SHORT
LIVED AS A SHORTWAVE QUICKLY APPROACHES THE REGION ON SUNDAY WITH
PRESSURE FALLS OCCURRING DURING THE DAY IN ADVANCE OF IT. WINDS
COULD BE CLOSE TO HIGH WIND CRITERIA IN THE WIND PRONE AREAS
(ESPECIALLY ARLINGTON AND BORDEAUX) ON SUNDAY AFTERNOON AND
EVENING. SHORTWAVE IS REALLY PROGRESSIVE...AND WHILE SNOW WILL
BECOME LIKELY OVER THE SIERRA MADRE AND SNOWY RANGES BY SUN
AFTN...IT WILL END BY SUN EVENING IN THE SUBSIDENCE BEHIND THE
SYSTEM. STRONG ZONAL FLOW ALOFT WILL COMBINE WITH A STRONG
PRESSURE GRADIENT TO MAINTAIN WINDY CONDITIONS OVER SOUTHEAST
WYOMING THROUGH MONDAY. TEMPS WILL BE MILD...ESPECIALLY ON SUN AND
MON...WHEN HIGHS IN THE 50S WILL BE COMMON OVER THE PLAINS.
.LONG TERM...(TUESDAY THROUGH SATURDAY)
ISSUED AT 400 AM MST SAT FEB 15 2014
PROGRESSIVE ZONAL FLOW WILL DOMINATE NEXT WEEK WITH A DEEPER TROUGH
AND COLDER AIR MASS ARRIVING FOR THE SECOND HALF OF THE WEEK. WINDS
WILL BE THE MAIN CONCERN DURING THE MIDDLE OF NEXT WEEK...ESPECIALLY
FOR AREAS ALONG AND WEST OF I-25. WOULD NOT BE SURPRISED IF TUESDAY
NIGHT AND WEDNESDAY MORNING NEEDS ANOTHER WIND HIGHLIGHT FOR THE
WIND PRONE AREAS IN TIME AS SHORTWAVE ENERGY AND REFLECTED SFC LOW
STRENGTHENS PREFRONTAL LLVL GRADIENTS. BY WEDNESDAY AFTERNOON...BOTH
MEDIUM RANGE MODELS ARE CONSISTENT IN TRACKING A COLD FRONT THRU THE
CWFA. ASIDE FROM PERHAPS A BRIEF BORA EVENT WITH THE FRONT...EXPECT
WINDS TO BE LESS FOR THE THURSDAY THROUGH SATURDAY TIMEFRAME AS THE
COLDER AIR MASS TAKES CONTROL. BEST PRECIPITATION CHANCES THROUGH
THE PERIOD WILL FALL IN THE SNOWY/SIERRA MADRE RANGES WHERE
PERSISTENT QUICK ZONAL FLOW ENHANCES OROGRAPHIC ASCENT. AS FOR LOWER
ELEVATIONS...EXPECT A BRIEF PERIOD ASSOCIATED WITH FROPA WEDNESDAY
AFTERNOON AND WEDNESDAY NIGHT...WITH PERHAPS ANOTHER PERIOD OF LIGHT
SNOW ON FRIDAY AS THE COLD AIR MASS IS REINFORCED BY A SECOND FRONT.
AT THIS POINT...ONLY LIGHT ACCUMULATIONS WILL BE POSSIBLE OUTSIDE OF
THE MOUNTAINS. THE WARMER PREFRONTAL AIR MASS WILL YIELD TUESDAY AND
WEDNESDAY AS THE WARMEST DAYS OF THE PERIOD. ON THESE DAYS H7
TEMPERATURES OF -2C TO -6C WILL YIELD AFTERNOON HIGHS CLOSE TO 40
WEST OF THE LARAMIE RANGE...WITH UPPER 40S TO LOW 50S OUT ON THE
EASTERN PLAINS. OF COURSE THE EASTERN PLAINS TEMPERATURES WILL BE
ENHANCED BY DOWNSLOPE ASSUMING LEE-SIDE LENTICULARS DONT CUT INTO
HIGHS. THIS ALL CHANGES FOR THURSDAY THROUGH SATURDAY HOWEVER AS H7
TEMPS PLUMMET TO -10C TO -13C. AS SUCH HIGHS WILL FALL BACK INTO THE
30S BY THE END OF THE WEEK...WITH EVEN SOME 20S FOR SATURDAY. WITH
CLIMATOLOGYS INFLUENCE ON MOS DATA...THESE MAY EVEN BE A BIT
OPTIMISTIC.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY EVENING)
ISSUED AT 1035 PM MST FRI FEB 14 2014
STILL SOME CONCERNS FOR LOWERING FLIGHT CONDITIONS AS A COLD FRONT
SAGS INTO THE AREA FROM THE NORTHWEST. TIMING ON THE FRONT LOOKS
TO BE AROUND THE 12Z TIME FRAME WITH SNOW DEVELOPING OVER THE
LARAMIE RANGE AND POSSIBLY OUT BY LARAMIE AT THAT TIME. OF
NOTE...THE LATEST HRRR FORECAST KEEPS THE PANHANDLE VFR THROUGH
12Z...SO CONFIDENCE IS SOMEWHAT HIGH THAT OUR AIRPORTS OUT THAT
WAY WILL BE FINE.
&&
.FIRE WEATHER...
ISSUED AT 400 AM MST SAT FEB 15 2014
MINIMAL FIRE WEATHER CONCERNS THROUGH EARLY NEXT WEEK.
TEMPERATURES WILL BE 10-15 DEGREES ABOVE NORMAL BUT MINIMUM
AFTERNOON HUMIDITY VALUES WILL GENERALLY BE ABOVE 30 PERCENT.
WINDY CONDITIONS WILL PERSIST THROUGH THE MIDDLE PART OF NEXT
WEEK...ESPECIALLY ACROSS SOUTHEAST WYOMING.
&&
.CYS WATCHES/WARNINGS/ADVISORIES...
WY...HIGH WIND WARNING UNTIL NOON MST TODAY FOR WYZ106-110-114-116-
117.
HIGH WIND WARNING UNTIL 5 AM MST EARLY THIS MORNING FOR WYZ104-
109-115.
NE...NONE.
&&
$$
SHORT TERM...FINCH
LONG TERM...HAHN
AVIATION...CLAYCOMB
FIRE WEATHER...FINCH
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
216 PM CST Sat Feb 15 2014
...Updated long term discussion...
.SHORT TERM...(Today and tonight)
ISSUED AT 123 AM CST SAT FEB 15 2014
Today:
Pretty interesting temperature forecast for today. A lee low with an
associated warm front will clip the southern part of the forecast area
of responsibility during the afternoon. Here, very warm 850 hPa temperatures
of 18-20C & downslope plume will be pretty close to the Colorado and
Oklahoma state borders. The tail end of the HRRR is also latching on
to this in the reflection of a sfc thermal gradient across far southwest
Kansas. Think that mid 70sF will be a distinct possibility by Elkhart.
Elsewhere, an approaching cold front will move across portions of southwest
Kansas today. As seen with yesterday, there will be considerable mixing
and think that the NAM is under-doing this and the low level thermal
gradient. Will call for a gradient of low 60sF across much of the forecast
area with mid 60sF to low 70sF across far western Kansas.
Tonight:
By this evening, high pressure will ridge across the outlook area with
fairly light winds. There will be weak upslope flow across western
Kansas with weak warm air advection in the low levels on the backside
of the departing high. The NAM/NSSL WRF/SREF probabilities show fog
potential for Sunday morning. Not very confident in spatial arrangement
of fog, but have added it in the wx grids in case these three models
are correct. Future shifts can adjust as necessary. Dewpoints won`t
be very high, but there could be a radiational fog environment with
an inversion and light sfc winds. Overnight minimums will be higher
as fog and mid to high level cloud cover lingers. Saw no reason to deviate
from previous forecast, which is widespread low 30s for lows.
.LONG TERM...(Sunday night through Saturday)
ISSUED AT 216 PM CST SAT FEB 15 2014
The 12z medium range models are all similar in showing a fairly zonal
upper flow pattern with fast moving shortwave troughs moving east
over the country in the flow. The first wave is progged to move
out over the Plains Sunday night with another wave progged to move
out around Wednesday night into Thursday. The models tend to keep
the strongest upper level energy, and consequently any significant
precipitation associated with these waves confined to the northern
Plains. On Wednesday night the models show that the low level moisture
return makes a brief show in central Kansas but it gets rapidly
shunted off to the east. The 12z ECMWF is more in line with the
GFS and not quite as amplified as its previous run, which suggested
a rain changing over to snow. Not overly impressed with precipitation
chances but given the uncertainty and in deference to my neighboring
WFOs, will keep some slight chance pops for rain or a rain/snow
mix over central and south central Kansas from Wednesday night
into Thursday.
Late in the week on into next weekend, the models are indicating
that the upper level ridge along the west coast of North America
will undergo some amplification. As this occurs, the models show a
deep trough developing over the central Plains during the weekend.
This would bring about another period of colder than normal
temperatures to western Kansas through the weekend into early the
following week.
&&
.AVIATION...(For the 18Z TAFS through 18Z Sunday afternoon)
ISSUED AT 1118 AM CST SAT FEB 15 2014
Winds will shift to more of a northerly direction today with wind
speeds around 15 knots gusting to over 20 knots at times. Wind
speeds then decrease to around 10 knots by early this evening. VFR
conditions will prevail with only a few high clouds.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 31 61 39 57 / 0 0 0 0
GCK 32 62 39 56 / 0 0 0 0
EHA 32 69 41 58 / 0 0 0 0
LBL 32 66 41 58 / 0 0 0 0
HYS 30 57 36 56 / 0 0 0 0
P28 32 59 40 59 / 0 0 0 0
&&
.DDC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...Sugden
LONG TERM...Gerard
AVIATION...Hovorka_42
AREA FORECAST DISCUSSION
NWS GOODLAND KS
1042 AM MST SAT FEB 15 2014
.UPDATE...
ISSUED AT 951 AM MST SAT FEB 15 2014
JUST COMPLETED AN UPDATE. PROBLEMATIC TEMPERATURE FORECAST TODAY.
MODELS NOT HANDLING SURFACE PATTERN WELL AS COLD FRONT HAS SURGED
SOUTH FASTER AND WITH COLDER AIR THAN ADVERTISED. THE LATEST TWO
VERSIONS OF THE RAP HAVE CAUGHT ONTO THE WIND AND LAYOUT OF THE
TEMPERATURES. SOME LOCATIONS MAY END UP REMAINING STEADY OR EVEN
SLOWLY FALLING FOR THE REST OF THE TODAY. SO USED IT AT AS A BASIS
FOR THIS UPDATE. WILL KEEP WATCHING TRENDS OF COURSE BUT WOULD NOT
BE SURPRISED IF HAVE TO DO ANOTHER UPDATE.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 228 AM MST SAT FEB 15 2014
ZONAL FLOW ALOFT OVER THE UNITED STATES KEEPS THE PATTERN
PROGRESSIVE THROUGH THE SHORT TERM PERIOD WITH GENERALLY WARM AND
DRY CONDITIONS EXPECTED. FORECAST CONCERN IS THE POSSIBILITY OF
STRONGER WINDS SUNDAY AND SUNDAY NIGHT.
THE UPPER RIDGE CURRENTLY IN PLACE OVER THE WESTERN UNITED STATES
TRANSLATES EAST ACROSS THE ROCKIES TODAY AND THE HIGH PLAINS
TONIGHT AHEAD OF A THROUGH THAT MOVES THROUGH THEW INTERMOUNTAIN
WEST ON SUNDAY AND ACROSS THE HIGH PLAINS REGION SUNDAY NIGHT.
WESTERLY FLOW REMAINS IN PLACE MONDAY AND MONDAY NIGHT. AT THE
SURFACE...BREEZY SOUTHWEST WINDS WILL TURN NORTHWEST BEHIND A COLD
FRONT THAT MOVES THROUGH THE FORECAST AREA BY MID DAY TODAY. A
COOLER AREA OF HIGH PRESSURE MOVES QUICKLY THROUGH THE FORECAST
AREA OVERNIGHT WITH WINDS TURNING BACK TO THE SOUTHWEST BY SUNDAY
MORNING AS A PREFRONTAL TROUGH DEEPENS ALONG THE FRONT RANGE AHEAD
OF THE APPROACHING UPPER TROUGH. SURFACE WINDS TURN NORTHWEST
AGAIN WITH THE PASSAGE OF ANOTHER COLD FRONT SUNDAY EVENING.
MODELS ARE HINTING AT THE POSSIBILITY OF SOME LIGHT PRECIPITATION
ACROSS THE FAR NORTH AND NORTHEAST SECTIONS OF THE FORECAST AREA
SUNDAY NIGHT...BUT THE BULK OF THE QPF SHOWING UP REMAINS NORTH OF
THE FORECAST AREA AND HAVE DECIDED TO LEAVE ANY POSSIBILITY OF
PRECIPITATION OUT OF THE FORECAST FOR NOW. SURFACE WINDS RETURN
QUICKLY TO THE SOUTHWEST AS ANOTHER LEE TROUGH DEEPENS ALONG THE
FRONT RANGE IN RESPONSE TO THE WESTERLY FLOW ALOFT. THIS SURFACE
TROUGH MOVES EAST MONDAY NIGHT WITH GENERALLY WESTERLY WINDS
ACROSS THE FORECAST AREA.
BREEZY AND GUSTY SOUTHWEST WINDS ARE EXPECTED AHEAD OF THE COLD
FRONT ON SUNDAY WITH BREEZY AND GUSTY NORTHWEST WINDS BEHIND THE
FRONT SUNDAY NIGHT. HAVE HELD OFF ON ANY WIND HIGHLIGHTS AT THIS
TIME SINCE MODEL WIND SPEEDS ARE CURRENTLY BELOW ADVISORY
THRESHOLDS AND TRANSITION THE FORECAST AREA PRETTY QUICKLY...BUT
MAY NEED TO ISSUE A WIND HIGHLIGHT IF WIND SPEEDS LOOK LIKE THEY
WILL BE STRONGER OR ARE SUSTAINED FOR A LONGER TIME PERIOD THAN
CURRENTLY ADVERTISED.
.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 228 AM MST SAT FEB 15 2014
UPPER LEVEL FLOW WILL BE WESTERLY IN A ZONAL FLOW PATTERN OVER THE
TRI STATE AREA FOR TUESDAY...RESULTING IN QUIET WEATHER WITH FAIR
CONDITIONS. A RIDGE WILL BUILD FROM THE WEST AND WILL MOVE INTO THE
HIGH PLAINS WEDNESDAY. A TROUGH WILL DEVELOP AND MOVE THROUGH THE
FORECAST AREA WEDNESDAY NIGHT IN ASSOCIATION WITH A CLOSED UPPER
LEVEL LOW FORECAST TO MOVE ACROSS THE NORTH CENTRAL PLAINS. A SECOND
PUSH OF COLDER AIR ALOFT WILL MOVE INTO THE REGION FRIDAY NIGHT INTO
SATURDAY MORNING.
NUMEROUS FRONTAL PASSAGES WILL TAKE PLACE DURING THE EXTENDED
FORECAST. A WEAK COLD FRONT WILL MOVE THROUGH THE HIGH PLAINS
TUESDAY. GUIDANCE SUGGESTS SURFACE TEMPERATURES WILL REACH THE LOWER
60S. HOWEVER COLD AIR ADVECTION AT 850 MB WITH TEMPERATURES BETWEEN
8 AND 12 CELSIUS...ALONG WITH NORTHWEST WINDS AT THE
SURFACE...SUGGEST TEMPERATURES CLOSER TO THE MIDDLE 50S. LOWERED
TEMPERATURES A BIT FROM WHAT INIT PROCEDURE PLACED IN THE FORECAST.
REGARDLESS OF TEMPERATURES...WEATHER IS EXPECTED TO BE QUIET FOR TUESDAY.
A WARM FRONT WILL PASS OVER THE HIGH PLAINS WEDNESDAY WITH PLENTY OF
WARM AIR ADVECTION AT 850 MB AND THE SURFACE. WITH 850 TEMPERATURES
FROM GUIDANCE BETWEEN 12 AND 15 CELSIUS...TEMPERATURES AT THE
SURFACE WILL MORE LIKELY REACH THE UPPER 50S TO LOW 60S IN THE
AFTERNOON. THE WEATHER COULD BECOME MORE INTERESTING WEDNESDAY NIGHT
AS A COLD FRONT APPROACHES THE AREA FROM THE NORTHWEST. MODEL
GUIDANCE DIFFERS AS TO THE TIMING OF THE FRONTAL PASSAGE...BUT SLIGHT
CHANCES FOR PRECIPITATION ARE POSSIBLE FOR THE AREA. 1000 TO 500 MB
MODEL THICKNESS DIFFER SOMEWHAT AS TO PLACEMENT OF THE RAIN/SNOW
LINE... BUT CONSENSUS GENERALLY INDICATES WARM SECTOR WILL START
OVER THE AREA BEFORE THE COLD SECTOR MOVES INTO THE AREA THURSDAY
MORNING. THEREFORE IF PRECIPITATION DOES OCCUR...IT WILL PROBABLY
START OUT AS RAIN OVERNIGHT WEDNESDAY AND TRANSITION INTO A MIXTURE
OF SNOW AND RAIN SOMETIME THURSDAY MORNING.
TEMPERATURES WILL STAY RIGHT AROUND AVERAGE FOR THURSDAY AND
FRIDAY...WITH HIGHS REACHING THE UPPER 40S TO LOWER 50S. ANOTHER
COLD FRONT WILL PUSH THROUGH THE HIGH PLAINS FRIDAY NIGHT...WHICH
WILL DECREASE HIGH TEMPERATURES INTO THE UPPER 30S TO LOWER 40S FOR
SATURDAY. SOME LIGHT SNOW SHOWERS MIGHT OCCUR WITH THE FRONTAL
PASSAGE...BUT NO SIGNIFICANT SNOW ACCUMULATIONS ARE EXPECTED AT THIS
TIME.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON)
ISSUED AT 1039 AM MST SAT FEB 15 2014
VARIABLE AND CHANGING CONDITIONS ACROSS THE AREA...ESPECIALLY NEAR
KGLD. STRONG COLD FRONT HAS SURGED SOUTH. FOR KGLD...THIS WILL
CREATE NEAR MVFR OR MVFR CONDITIONS THROUGH THE MIDDLE OF THE
AFTERNOON. OTHERWISE THE REMAINDER OF THE PERIOD FOR KGLD AND THE
ENTIRE PERIOD AT KMCK WILL BE VFR. WINDS WILL GUSTY OUT OF THE
NORTH FOR THE REST OF THE AFTERNOON.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
UPDATE...BULLER
SHORT TERM...LOCKHART
LONG TERM...99
AVIATION...BULLER
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
1121 AM CST Sat Feb 15 2014
...Updated aviation section...
.SHORT TERM...(Today and tonight)
ISSUED AT 123 AM CST SAT FEB 15 2014
Today:
Pretty interesting temperature forecast for today. A lee low with an
associated warm front will clip the southern part of the forecast area
of responsibility during the afternoon. Here, very warm 850 hPa temperatures
of 18-20C & downslope plume will be pretty close to the Colorado and
Oklahoma state borders. The tail end of the HRRR is also latching on
to this in the reflection of a sfc thermal gradient across far southwest
Kansas. Think that mid 70sF will be a distinct possibility by Elkhart.
Elsewhere, an approaching cold front will move across portions of southwest
Kansas today. As seen with yesterday, there will be considerable mixing
and think that the NAM is under-doing this and the low level thermal
gradient. Will call for a gradient of low 60sF across much of the forecast
area with mid 60sF to low 70sF across far western Kansas.
Tonight:
By this evening, high pressure will ridge across the outlook area with
fairly light winds. There will be weak upslope flow across western
Kansas with weak warm air advection in the low levels on the backside
of the departing high. The NAM/NSSL WRF/SREF probabilities show fog
potential for Sunday morning. Not very confident in spatial arrangement
of fog, but have added it in the wx grids in case these three models
are correct. Future shifts can adjust as necessary. Dewpoints won`t
be very high, but there could be a radiational fog environment with
an inversion and light sfc winds. Overnight minimums will be higher
as fog and mid to high level cloud cover lingers. Saw no reason to deviate
from previous forecast, which is widespread low 30s for lows.
.LONG TERM...(Sunday through Friday)
ISSUED AT 314 AM CST SAT FEB 15 2014
On Sunday, there will be a nearly zonal flow over the plains, with a
cold front approaching from the north. It should be mostly sunny
with mainly high cirrus clouds passing overhead. Winds will be from
the southwest and the pressure gradient will tighten up in the
afternoon as the cold front encroaches. Winds should start out
from the southwest at 5 to 15 mph in the morning, but increase
from the southwest at 15 to 20 mph with gusts to near 30 mph in
the afternoon. It should warm up nicely into the upper 50s to
lower 60s, but the winds will still be noticeable. Sunday night
could be windier than Sunday, as the cold front moves through.
South winds will shift to the northwest at 15 to 30 mph, gusting
as high as 40 mph. A wind advisory may be needed for parts of
Sunday night and Monday morning. Those strong winds will continue
into Monday morning, bringing the same 20 mph to 30 mph gusting to
40 mph range to that area east of a Scott City to Meade line. By
late Monday, winds should be from the west at around 10 mph. The
cold front will bring down max temps somewhat, into the middle
50s.
Tuesday will respond to a wind shift back to the southwest, with
mostly sunny skies and maximum temperatures in the middle to upper 60s.
A zonal flow will return aloft Tuesday into Wednesday. Wednesday
should be the warmest day overall, with lower 60s expected north of
I-70, and maxes around 70F along the Oklahoma border. A large upper
level trough will approach from the west Wednesday night, bringing
first a slight chance for rain to our western CWA, basically west of
a Hays to Liberal line, and then a chance for light snow after
midnight Wednesday night. By Thursday morning, there will be a cold
front dragging through southwest Kansas, the precip may be either
rain or snow Thursday morning. By afternoon, the lower layers
should warm up enough to change any precipitation back to rain,
east of a Scott City to Garden City to near Liberal line. Right
now, I do not think anyone will get more than light rain or light
snow.
We will go into a zonal flow aloft by Friday, and then to a
southwest upper level flow by Saturday. Friday will be a moderating
day with highs in the mid 50s to lower 60s, then clouds and shallow
cold air spilling south from the northern plains will dip maximum temperatures
back into the lower to middle 40s by Saturday, which will be closer
to climatological highs.
&&
.AVIATION...(For the 18Z TAFS through 18Z Sunday afternoon)
ISSUED AT 1118 AM CST SAT FEB 15 2014
Winds will shift to more of a northerly direction today with wind
speeds around 15 knots gusting to over 20 knots at times. Wind
speeds then decrease to around 10 knots by early this evening. VFR
conditions will prevail with only a few high clouds.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 62 31 61 39 / 0 0 0 0
GCK 63 32 62 39 / 0 0 0 0
EHA 76 32 69 41 / 0 0 0 0
LBL 69 32 66 41 / 0 0 0 0
HYS 61 30 57 36 / 0 0 0 0
P28 61 32 59 40 / 0 0 0 0
&&
.DDC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...Sugden
LONG TERM...Burke
AVIATION...Hovorka_42
AREA FORECAST DISCUSSION
NWS GOODLAND KS
1006 AM MST SAT FEB 15 2014
.UPDATE...
ISSUED AT 951 AM MST SAT FEB 15 2014
JUST COMPLETED AN UPDATE. PROBLEMATIC TEMPERATURE FORECAST TODAY.
MODELS NOT HANDLING SURFACE PATTERN WELL AS COLD FRONT HAS SURGED
SOUTH FASTER AND WITH COLDER AIR THAN ADVERTISED. THE LATEST TWO
VERSIONS OF THE RAP HAVE CAUGHT ONTO THE WIND AND LAYOUT OF THE
TEMPERATURES. SOME LOCATIONS MAY END UP REMAINING STEADY OR EVEN
SLOWLY FALLING FOR THE REST OF THE TODAY. SO USED IT AT AS A BASIS
FOR THIS UPDATE. WILL KEEP WATCHING TRENDS OF COURSE BUT WOULD NOT
BE SURPRISED IF HAVE TO DO ANOTHER UPDATE.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 228 AM MST SAT FEB 15 2014
ZONAL FLOW ALOFT OVER THE UNITED STATES KEEPS THE PATTERN
PROGRESSIVE THROUGH THE SHORT TERM PERIOD WITH GENERALLY WARM AND
DRY CONDITIONS EXPECTED. FORECAST CONCERN IS THE POSSIBILITY OF
STRONGER WINDS SUNDAY AND SUNDAY NIGHT.
THE UPPER RIDGE CURRENTLY IN PLACE OVER THE WESTERN UNITED STATES
TRANSLATES EAST ACROSS THE ROCKIES TODAY AND THE HIGH PLAINS
TONIGHT AHEAD OF A THROUGH THAT MOVES THROUGH THEW INTERMOUNTAIN
WEST ON SUNDAY AND ACROSS THE HIGH PLAINS REGION SUNDAY NIGHT.
WESTERLY FLOW REMAINS IN PLACE MONDAY AND MONDAY NIGHT. AT THE
SURFACE...BREEZY SOUTHWEST WINDS WILL TURN NORTHWEST BEHIND A COLD
FRONT THAT MOVES THROUGH THE FORECAST AREA BY MID DAY TODAY. A
COOLER AREA OF HIGH PRESSURE MOVES QUICKLY THROUGH THE FORECAST
AREA OVERNIGHT WITH WINDS TURNING BACK TO THE SOUTHWEST BY SUNDAY
MORNING AS A PREFRONTAL TROUGH DEEPENS ALONG THE FRONT RANGE AHEAD
OF THE APPROACHING UPPER TROUGH. SURFACE WINDS TURN NORTHWEST
AGAIN WITH THE PASSAGE OF ANOTHER COLD FRONT SUNDAY EVENING.
MODELS ARE HINTING AT THE POSSIBILITY OF SOME LIGHT PRECIPITATION
ACROSS THE FAR NORTH AND NORTHEAST SECTIONS OF THE FORECAST AREA
SUNDAY NIGHT...BUT THE BULK OF THE QPF SHOWING UP REMAINS NORTH OF
THE FORECAST AREA AND HAVE DECIDED TO LEAVE ANY POSSIBILITY OF
PRECIPITATION OUT OF THE FORECAST FOR NOW. SURFACE WINDS RETURN
QUICKLY TO THE SOUTHWEST AS ANOTHER LEE TROUGH DEEPENS ALONG THE
FRONT RANGE IN RESPONSE TO THE WESTERLY FLOW ALOFT. THIS SURFACE
TROUGH MOVES EAST MONDAY NIGHT WITH GENERALLY WESTERLY WINDS
ACROSS THE FORECAST AREA.
BREEZY AND GUSTY SOUTHWEST WINDS ARE EXPECTED AHEAD OF THE COLD
FRONT ON SUNDAY WITH BREEZY AND GUSTY NORTHWEST WINDS BEHIND THE
FRONT SUNDAY NIGHT. HAVE HELD OFF ON ANY WIND HIGHLIGHTS AT THIS
TIME SINCE MODEL WIND SPEEDS ARE CURRENTLY BELOW ADVISORY
THRESHOLDS AND TRANSITION THE FORECAST AREA PRETTY QUICKLY...BUT
MAY NEED TO ISSUE A WIND HIGHLIGHT IF WIND SPEEDS LOOK LIKE THEY
WILL BE STRONGER OR ARE SUSTAINED FOR A LONGER TIME PERIOD THAN
CURRENTLY ADVERTISED.
.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 228 AM MST SAT FEB 15 2014
UPPER LEVEL FLOW WILL BE WESTERLY IN A ZONAL FLOW PATTERN OVER THE
TRI STATE AREA FOR TUESDAY...RESULTING IN QUIET WEATHER WITH FAIR
CONDITIONS. A RIDGE WILL BUILD FROM THE WEST AND WILL MOVE INTO THE
HIGH PLAINS WEDNESDAY. A TROUGH WILL DEVELOP AND MOVE THROUGH THE
FORECAST AREA WEDNESDAY NIGHT IN ASSOCIATION WITH A CLOSED UPPER
LEVEL LOW FORECAST TO MOVE ACROSS THE NORTH CENTRAL PLAINS. A SECOND
PUSH OF COLDER AIR ALOFT WILL MOVE INTO THE REGION FRIDAY NIGHT INTO
SATURDAY MORNING.
NUMEROUS FRONTAL PASSAGES WILL TAKE PLACE DURING THE EXTENDED
FORECAST. A WEAK COLD FRONT WILL MOVE THROUGH THE HIGH PLAINS
TUESDAY. GUIDANCE SUGGESTS SURFACE TEMPERATURES WILL REACH THE LOWER
60S. HOWEVER COLD AIR ADVECTION AT 850 MB WITH TEMPERATURES BETWEEN
8 AND 12 CELSIUS...ALONG WITH NORTHWEST WINDS AT THE
SURFACE...SUGGEST TEMPERATURES CLOSER TO THE MIDDLE 50S. LOWERED
TEMPERATURES A BIT FROM WHAT INIT PROCEDURE PLACED IN THE FORECAST.
REGARDLESS OF TEMPERATURES...WEATHER IS EXPECTED TO BE QUIET FOR TUESDAY.
A WARM FRONT WILL PASS OVER THE HIGH PLAINS WEDNESDAY WITH PLENTY OF
WARM AIR ADVECTION AT 850 MB AND THE SURFACE. WITH 850 TEMPERATURES
FROM GUIDANCE BETWEEN 12 AND 15 CELSIUS...TEMPERATURES AT THE
SURFACE WILL MORE LIKELY REACH THE UPPER 50S TO LOW 60S IN THE
AFTERNOON. THE WEATHER COULD BECOME MORE INTERESTING WEDNESDAY NIGHT
AS A COLD FRONT APPROACHES THE AREA FROM THE NORTHWEST. MODEL
GUIDANCE DIFFERS AS TO THE TIMING OF THE FRONTAL PASSAGE...BUT SLIGHT
CHANCES FOR PRECIPITATION ARE POSSIBLE FOR THE AREA. 1000 TO 500 MB
MODEL THICKNESS DIFFER SOMEWHAT AS TO PLACEMENT OF THE RAIN/SNOW
LINE... BUT CONSENSUS GENERALLY INDICATES WARM SECTOR WILL START
OVER THE AREA BEFORE THE COLD SECTOR MOVES INTO THE AREA THURSDAY
MORNING. THEREFORE IF PRECIPITATION DOES OCCUR...IT WILL PROBABLY
START OUT AS RAIN OVERNIGHT WEDNESDAY AND TRANSITION INTO A MIXTURE
OF SNOW AND RAIN SOMETIME THURSDAY MORNING.
TEMPERATURES WILL STAY RIGHT AROUND AVERAGE FOR THURSDAY AND
FRIDAY...WITH HIGHS REACHING THE UPPER 40S TO LOWER 50S. ANOTHER
COLD FRONT WILL PUSH THROUGH THE HIGH PLAINS FRIDAY NIGHT...WHICH
WILL DECREASE HIGH TEMPERATURES INTO THE UPPER 30S TO LOWER 40S FOR
SATURDAY. SOME LIGHT SNOW SHOWERS MIGHT OCCUR WITH THE FRONTAL
PASSAGE...BUT NO SIGNIFICANT SNOW ACCUMULATIONS ARE EXPECTED AT THIS
TIME.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SUNDAY MORNING)
ISSUED AT 430 AM MST SAT FEB 15 2014
CONDITIONS ARE EXPECTED TO REMAIN VFR THROUGH THE TAF PERIOD AT
MCK AND GLD. SOUTHWEST WINDS WILL TURN NORTHWEST AND BECOME GUSTY
BETWEEN 15Z-18Z AS A COLD FRONT MOVES THROUGH THE CENTRAL HIGH
PLAINS REGION. SKY COVER WILL INCREASE AND CEILINGS WILL
LOWER AS THE FRONT MOVES THROUGH...WITH DECREASING SKY COVER AND
HIGHER CLOUD BASES OVERNIGHT.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
UPDATE...BULLER
SHORT TERM...LOCKHART
LONG TERM...99
AVIATION...LOCKHART
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
349 PM EST SAT FEB 15 2014
.SHORT TERM...(THIS EVENING THROUGH SUNDAY)
ISSUED AT 345 PM EST SAT FEB 15 2014
WV IMAGERY AND RUC ANALYSIS INDICATED A WELL-DEFINED UPSTREAM
CLIPPER SHORTWAVE TROUGH INTO NRN MN AND ANOTHER TO THE SOUTH OVER
IA. RELATIVELY STEEP 700-500 MB LAPSE RATES FROM 7.5C-8.0C/KM HAS
HELPED MAXIMIZING LIFT WITH THE MODERATE 700-500 MB QVECTOR CONV
AHEAD OF THE SHRTWV HAS SUPPORTED AREAS OF MODERATE SNOW FROM NRN MN
INTO WRN LAKE SUPERIOR. THE SNOW ALSO FROM NRN MN INTO THE KEWEENAW
ALSO HAD A CONVECTIVE APPEARANCE...PER VIS SATELLITE LOOP.
OTHERWISE...CLOUDS WERE THICKENING ACROSS THE REST OF UPPER MI AS
THE AREA OF SNOW FROM NEAR DLH INTO NW WI APPROACHED IWD.
THE INITIAL FOCUS FOR THE HEAVIER SNOW INTO THE KEWEENAW THIS
AFTERNOON WAS ALIGNED WITH 800-600 MB FGEN.
HOWEVER...SATELLITE/RADAR TRENDS AND THE NAM/REGIONAL GEM SUGGEST
THAT THE STRONGER FORCING WILL SLIDE THROUGH WRN AND WRN UPPER MI
THIS EVENING AHEAD OF THE SHRTWV. UPSTREAM OBS AND MODELS CONSENSUS
QPF OF 0.10 TO 0.15 INCH WITH THE SLR VALUES OF AROUND 20/1 WOULD
GIVE SNOWFALL AMOUNTS IN THE 2 TO 3 INCH RANGE. SOME LOCAL HIGHER
AMOUNTS MAY BE POSSIBLE OVER THE KEWEENAW WHERE THE DURATION OF FGEN
FORCING AND LOCALLY WHERE THE CONVECTIVE NATURE OF THE SNOW SQUEEZES
OUT SOME GREATER AMOUNTS. AMOUNTS OVER THE KEWEENAW WOULD LIKELY BE
MUCH HIGHER BUT THE EXTENSIVE ICE COVER HAS LIMITED ANY LAKE
ENHANCEMENT WITH THE LOW LEVEL ERLY FLOW. EXPECT THE SNOW TO
DIMINISH QUICKLY FROM WEST TO EAST LATE THIS EVENING AS THE SHRTWV
DEPARTS.
HIGH PRES WILL BUILD INTO THE REGION LATE TONIGHT AND SUNDAY WITH
LOW LEVEL NE FLOW. THERE MAY ALSO BE SOME LIGHT LES INTO N CNTRL
UPPER MI WITH SOME MOISTURE/HEAT FLUX FROM ANY GAPS IN THE LAKE ICE
COVER. LOW LEVEL MOISTURE WILL ALSO GRADUALLY DIMINISH WITH PARTLY
SUNNY SKIES BY AFTERNOON. TEMPERATURES WILL REMAIN BELOW NORMAL WITH
HIGHS RECOVERING INTO THE MID AND UPPER TEENS.
.LONG TERM...(SUNDAY NIGHT THROUGH SATURDAY)
ISSUED AT 345 PM EST SAT FEB 15 2014
OVERALL PATTERN IN THE LONG TERM IS INITIALLY DRIVEN BY ENERGY
EJECTING OUT OF A DEEP UPPER LOW CURRENTLY OVER THE GULF OF AK. THAT
UPPER LOW WILL WEAKEN SIGNIFICANTLY MON INTO TUE...WITH SOME OF THE
REMAINING ENERGY BEING TRANSPORTED INTO THE WRN AND CENTRAL CONUS
MID-LATE THIS WEEK WHERE MODELS INDICATE IT WILL BE DEEPENED INTO A
AMPLIFIED UPPER TROUGH OVER THE PLAINS STATES.
THE FIRST WAVE OF ENERGY IS SET TO MOVE THROUGH THE AREA LATE MON
INTO MON NIGHT. A FEW THINGS ARE LEADING TO MODEL DISAGREEMENT ON
THE STRENGTH...TRACK AND TIMING OF THIS SYSTEM...WHICH IMPACTS
RELATED FIELDS SUCH AS QPF. FIRST...THE ENERGY IS STILL TIED TO THE
LOW AND IS OVER THE PACIFIC...AND THEREFORE OUT OF THE BETTER UPPER
LEVEL OBSERVATION NETWORK SO SAMPLING IS AT LEAST SOMEWHAT OF AN
ISSUE. SECOND...AND PROBABLY THE MORE SUBSTANTIAL REASON FOR
DISAGREEMENT...IS THAT THE ENERGY LOOKS TO BE SPLIT BETWEEN A NRN
AND SRN SHORTWAVE...THE SOUTHERN OF WHICH IS HELPED OUT BY AN JET
STREAK AND IS THE MAIN FEATURE. MODELS ARE HAVING TROUBLE /RUN TO
RUN AND MODEL TO MODEL/ WITH AGREEMENT ON HOW MUCH OF THE ENERGY TO
ALLOT TO EACH OF THE SHORTWAVES...ALONG WITH MOISTURE FIELDS AND
SUCH. THE 12Z/15 GFS AND 00Z/15 ECMWF REPRESENT TWO OF THE EXTREMES
WITH THE NRN SHORTWAVE. THE GFS IS WEAKER AND FASTER /WITH LOWER QPF
TOTALS LESS THAN 0.30 INCHES/ WHILE THE ECMWF IS STRONGER AND SLOWER
AND ACTUALLY HAS THE NRN SHORTWAVE BECOMING THE DOMINANT FEATURE
WHILE BECOMING CLOSED OFF OVER LOWER MI LATE MON. THE ECMWF HAS THE
MOST QPF AT 0.35-0.45 INCHES. WHILE NOT AT ALL SURE IF ANY OF THESE
TWO SOLUTIONS WILL BE CORRECT...WILL USE THE 12/15 NAM AND 12/15 GEM
SOLUTIONS WHICH ARE MORE IN THE MIDDLE OF THE ROAD. THE NAM IS
CLOSER TO THE GFS WHILE THE GEM IS CLOSER TO THE ECMWF...BUT THEY
ARE STILL MORE MODERATED SOLUTIONS TO THE TWO EXTREMES. THIS GIVES
TOTAL QPF OF 0.25-0.35 INCHES...WHICH TRANSLATES TO ROUGHLY 3-5
INCHES OF SNOW...WHICH MATCHES UP TO THE PREVIOUS SHIFT AS WELL.
ADDITIONAL...YET WEAKER...SHORTWAVES MAY MOVE THROUGH TUE INTO
WED...WITH CONTINUED MODEL DISAGREEMENT. HOWEVER...MOISTURE LOOKS TO
BE QUITE A BIT MORE LIMITED DURING THIS TIME FRAME SO WIDESPREAD
PRECIP IS NOT AS MUCH OF AN ISSUE. MORE INTERESTINGLY...MODELS BRING
AN 850MB THERMAL RIDGE ACROSS THE CWA LATE MON NIGHT THROUGH
TUE...BRINGING 850MB TEMPS AS WARM AS 0C ACROSS THE CWA. WHILE THIS
WILL ALLOW FOR MAX SFC TEMPS AROUND 30F...WET BULB ZERO TEMPS ABOVE
THE SFC WILL BE BELOW ZERO. THIS IS WHERE PRECIP IS MORE OF AN ISSUE
IN THAT THE DRY MID LEVELS WILL LEAVE THE DGZ DRY AND THE STRONG
INVERSION BENEATH THE THERMAL RIDGE WILL TRAP PLENTY OF MOISTURE IN
THE LOW LEVELS LATE MON NIGHT BEFORE THAT MOISTURE GETS MIXED BY
DAYTIME HEATING TUE. COULD SEE SOME FREEZING DRIZZLE N OF LAKE
MICHIGAN DUE TO SW WINDS OFF LAKE MICHIGAN AND UPSLOPE FLOW THERE.
AN UPPER TROUGH THEN TUE NIGHT/WED MORNING...BRINGING A COOLER
AIRMASS WITH IT. THE UPPER RIDGE THAT MODELS HAVE MOVING THROUGH
LATE WED/WED NIGHT IS SLOWER THAN PREVIOUS MODEL RUNS...SO TEMPS MAY
NOT GET AS WARM ON WED. WENT AHEAD AND LOWERED TEMPS A COUPLE OF
DEGREES WED.
THU THROUGH NEXT SUN IS EVEN MORE UNCERTAIN AS THE UPPER TROUGH
MOVES INTO THE PLAINS. QUESTIONS ABOUT STRENGTH AND PLACEMENT OF THE
TROUGH...ALONG WITH PHASING AND HOW MUCH/WHEN PIECES OF ENERGY CAN
EJECT FROM THE TROUGH ARE IMPOSSIBLE TO ANSWER AT THIS POINT. THERE
IS POTENTIAL FOR MUCH STRONGER SYSTEMS TO BE MOVING THROUGH THE
REGION...WHICH INCLUDES POSSIBILITIES OF SIGNIFICANT PRECIP /EITHER
MIXED PTYPE OR SNOW/. THIS PART OF THE FORECAST BEARS CLOSER
MONITORING BY THOSE WITH TRAVEL/OUTDOOR INTERESTS AS FORECASTS ARE
REFINED IN THE NEXT FEW DAYS. IT DOES LOOK LIKE ANOTHER ROUND OF
COLDER AIR WILL MOVED INTO THE REGION LATE IN THE FORECAST PERIOD
INTO EARLY NEXT WEEK. USED A CONSENSUS OF GUIDANCE AT THIS POINT
GIVEN THE POOR MODEL TO MODEL AGREEMENT AND RUN TO RUN CONTINUITY.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON)
ISSUED AT 1247 PM EST SAT FEB 15 2014
SNOW AND IFR CONDITIONS AT CMX WILL ALSO SPREAD TO IWD AND SAW LATE
THSI AFTERNOON AND EVENING AS A DISTURBANCE APPROACHES THE UPPER
LAKES. EXPECT CONDITIONS TO BEGIN IMPROVING TO MVFR BY LATE EVENING
AT KIWD AND KCMX AND OVERNIGHT TONIGHT AT KSAW.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 345 PM EST SAT FEB 15 2014
A SERIES OF WEAK TROUGHS MOVING THROUGH THE AREA WILL CONTINUE TO
BRING ROUNDS OF LIGHT TO SOMETIMES MODERATE SNOW THROUGH WEDNESDAY.
WINDS WILL GENERALLY STAY UNDER 20 KTS WITH TWO EXCEPTIONS. ONE WILL
BE LATE THIS AFTERNOON AND TONIGHT AS E-NE WINDS WILL INCREASE TO 15
TO 25 KNOTS OVER THE WESTERN LAKE. THE SECOND WILL BE THE POTENTIAL
FOR 20 TO 30 KT SE WINDS OVER MAINLY THE EAST HALF OF LAKE SUPERIOR
ON MONDAY AHEAD OF AN APPROACHING LOW PRESSURE SYSTEM. WITH THE LAKE
ALMOST COMPLETELY ICE COVERED...NO SIGNIFICANT AREAS OF FREEZING
SPRAY ARE EXPECTED.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
WINTER WEATHER ADVISORY UNTIL MIDNIGHT EST TONIGHT FOR MIZ001-
003.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...JLB
LONG TERM...TITUS
AVIATION...JLB
MARINE...JLB
AREA FORECAST DISCUSSION
NWS TWIN CITIES/CHANHASSEN MN
1121 AM CST SAT FEB 15 2014
.UPDATE...
ISSUED AT 1103 AM CST SAT FEB 15 2014
UPDATED TO INCLUDE 18Z AVIATION DISCUSSION BELOW.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 408 AM CST SAT FEB 15 2014
REGIONAL RADAR THIS MORNING HAS TWO AREAS OF ENHANCED REFLECTIVITY
ASSOCIATED WITH A STRONG JET STREAK MOVING SE ACROSS THE NORTHERN
PLAINS. ACROSS ND/SD...THE REFLECTIVITY PATTERN IS MORE DISORGANIZED
AND IS WEAKER COMPARED TO ANOTHER AREA IN NEBRASKA WHICH HAS A
BETTER ORIENTATION OF THE 92-70H FRONTOGENETIC REGIME. IN
ADDITION...ACROSS THE UPPER MIDWEST...MOISTURE IS LACKING IN THE
DENDRITIC GROWTH ZONE. ALTHOUGH THE LATEST 07Z RAP HAS INCREASED THE
MOISTURE IN THIS GROWTH ZONE BY 12-15Z IN WESTERN MN...AM NOT
TOTALLY CONVINCED BOTH THE MOISTURE AND LIFT WILL ORGANIZE ENOUGH TO
WARRANT CATEGORICAL POPS NORTH OF THE MN RIVER VALLEY. AM LEANING
TOWARD THE CONTINUED HIGHER POPS ALONG THE IA/MN BORDER BY
15-18Z...WITH LOWER CONFIDENCE FURTHER TO THE N/NE. WOULD LIKE TO
SEE MORE -SN OBS IN SD/ND BEFORE CONFIDENCE INCREASES FOR SNOWFALL
TOTALS GREATER THAN A LIGHT DUSTING NORTH OF THE MN RIVER VALLEY.
HOWEVER...DUE TO THE STRENGTH OF THE FORCING BY 15-18Z ALONG THE
IA/MN...THERE COULD BE A QUICK 1-2 INCHES OF SNOW BEFORE IT TAPERS
OFF BY EARLY AFTN. ELSEWHERE...CONFIDENCE IS LOW FOR ANYTHING MORE
THAN ONE HALF INCH. TEMPERATURES MAY REACH THE LOWER 30S ALONG THE
LEE OF THE BUFFALO RIDGE TODAY AS UPSTREAM OBS IN SW ND/NW SD HAVE
30S ALREADY THIS MORNING. THE MEAN FLOW IN THE BOUNDARY LAYER WILL
HELP ADVECT THESE TEMPS ACROSS SD...AND INTO SW MN LATER TODAY.
ELSEWHERE...20S WILL BE COMMON. NO CHGS ON THE FORECAST TONIGHT AS
CLEARING TAKES PLACE IN THE WAKE OF THIS SYSTEM.
.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 408 AM CST SAT FEB 15 2014
SEMI-ZONAL FLOW BECOMES ESTABLISHED BY 18Z SUNDAY...AND THE NEXT
SYSTEM RACES TOWARD THE AREA. THE ATTENDANT PV REFLECTION IS A BIT
DISJOINTED...WITH ONE POCKET PASSING ACROSS NORTHERN MN AND THE
OTHER PASSING ACROSS IOWA. REGARDLESS...SHOULD SEE A DECENT PERIOD
OF PRECIPITATION ON SUNDAY NIGHT AND MONDAY AS THE TROUGH TAKES ON
A SLIGHT NEGATIVE TILT AND A HEALTHY BURST OF ISENTROPIC UPGLIDE
ARRIVES /PER THE 280K-295K SURFACES/. THERMAL PROFILES ARE WARMER
WITH THIS SYSTEM...AND 0-6KM SFC WET BULB TEMPS ILLUSTRATE THE
POTENTIAL FOR LIGHT FREEZING DRIZZLE OR SLEET ACROSS
SOUTHWEST/SOUTH CENTRAL MN ON SUNDAY NIGHT BETWEEN 03Z AND
12Z...WITH AREAS OF FREEZING DRIZZLE ACROSS THE SOUTHEAST ON
MONDAY AFTERNOON AT THE END OF THE EVENT. SNOW ACCUMULATIONS DURING
THE 24 HOUR PERIOD /00Z MON-00Z TUE/ COULD APPROACH WARNING CRITERIA /6
INCHES/ IN OUR NORTHERN WEST CENTRAL WI COUNTIES...TAPERING TO
AROUND 3 INCHES IN THE TWIN CITIES...DOWN TO AROUND 1 INCH IN THE
SOUTHWEST WHERE THE POTENTIAL FOR MIXED PRECIP EXISTS.
TUESDAY THROUGH WEDNESDAY THEN LOOK TO BE BENIGN WEATHER-WISE IN
THE WAKE OF THE SYSTEM...WITH THE MAIN HIGHLIGHT BEING WARMER
TEMPERATURES WITH HIGHS IN THE MID 30S TO POSSIBLY EVEN LOWER 40S.
ATTENTION AT THE END OF THE WORK WEEK WILL BE FOCUSED ON THE
POTENTIAL FOR A NOTABLE SYSTEM BRINGING SIGNIFICANT SNOWFALL
ACCUMULATIONS TO THE REGION. MODEL SOLUTIONS ARE ADMITTEDLY ALL
OVER THE MAP WITH RESPECT TO THE SYNOPTIC DETAILS...BUT BOTH ECMWF
AND GFS MODELS HAVE BEEN INSISTENT ON THE ARRIVAL OF AT LEAST ONE
SUBSTANTIAL MID LATITUDE CYCLONE TOWARD NEXT WEEKEND. STAY TUNED...
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON)
ISSUED AT 1103 AM CST SAT FEB 15 2014
QUICKLY MOVING SHORTWAVE AND SURFACE LOW CURRENTLY WORKING
THROUGH THE REGION... HELPING TO GENERATE A BRIEF PERIOD OF
MODERATE TO HEAVY SNOWFALL... PARTICULARLY OVER SOUTHERN
LOCATIONS. CEILINGS AND VISIBILITIES WILL DIP INTO IFR RANGE FOR A
1-2 HOUR WINDOW AS THE ACTIVITY MOVES THROUGH... WITH SOME LOWER
CEILINGS THEN LINGERING INTO THE EVENING. MAIN
QUESTION/UNCERTAINTY IS WITH HOW LONG MVFR CEILINGS WILL LAST
TONIGHT. UPSTREAM OBS SUGGEST IT SHOULD REMAIN FOR A WHILE...
ALTHOUGH THE GUIDANCE WANTS TO DRY THINGS OUT IN THE BOUNDARY
LAYER DURING THE NIGHTTIME HOURS... AND THE DRIER AIR ISN/T TOO
FAR SOUTH OF THE MOISTURE STREAM ADVANCING FROM THE NORTHERN
DAKOTAS. WE SHOULD EVENTUALLY SCOUR IT OUT... AND WILL THEN BE
LOOKING AT ADVANCING AC AND CIRRUS AHEAD OF THE NEXT SYSTEM...
WHICH WILL IMPACT THE REGION SUNDAY NIGHT.
KMSP...PRIMARY CONCERNS ARE IN THE FIRST 1-2 HOURS OF THE
FORECAST... WHEN SOME LIFR CONDITIONS ARE EXPECTED WITH A SHORT
PERIOD OF HEAVY SNOW. THINGS WILL IMPROVE IN TERMS OF VISIBILITY
AS QUICKLY AS THEY DETERIORATE. THE MAIN QUESTION THEN BECOMES HOW
QUICKLY AND TO WHAT EXTENT CEILINGS WILL IMPROVE. FEEL THEY WILL
GET ABOVE 017 FT FAIRLY QUICKLY... BUT SHOULD SEE MVFR LINGERING
INTO TONIGHT FOR A DECENT AMOUNT OF TIME BEFORE SUFFICIENT
SUBSIDENCE AND DRY AIR CAN SCOUR THINGS OUT. HOWEVER... THAT IS
CERTAINLY SOMETHING TO WATCH AND THE IMPROVEMENT COULD COME
EARLIER/LATER THAN EXPECTED. THINGS WILL THEN BE QUIET THROUGH
SUNDAY UNTIL THE NEXT SYSTEM ARRIVES SUNDAY NIGHT.
/OUTLOOK FOR KMSP/
SUNDAY NIGHT AND MONDAY...MVFR CEILINGS AND VISIBILITIES EXPECTED
WITH SNOW... IFR CONDITIONS POSSIBLE. SOUTHEAST WIND 10 TO 20 KT
SHIFTING WEST.
MONDAY NIGHT...VFR. SOUTHWEST WIND 10 TO 20 KT.
TUESDAY...VFR. SOUTHWEST WIND 10 TO 20 KT SHIFTING WEST.
TUESDAY NIGHT...VFR. WEST WIND 5 TO 15 KT.
WEDNESDAY...MVFR CEILINGS POSSIBLE WITH A CHANCE OF RAIN. SOUTH
WIND 15 TO 25 KT.
&&
.MPX WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...NONE.
&&
$$
UPDATE...
SHORT TERM...JLT
LONG TERM...LS
AVIATION...
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
1135 AM CST SAT FEB 15 2014
.UPDATE...
ISSUED AT 1135 AM CST SAT FEB 15 2014
HAVE ADDED IN WINNESHEIK AND FAYETTE COUNTIES INTO THE ADVISORY.
15.12Z AND 15.15Z RAP GUIDANCE...ALONG WITH RADAR TRENDS...SUGGEST
THESE COUNTIES COULD ALSO PICK UP 2 TO 4 INCHES. ITS WORTH NOTING
THAT THE 15.15Z RAP SUGGESTS SOME OF THE HEAVIER SNOW COULD EVEN
SPREAD ONE MORE COLUMN OF COUNTIES EASTWARD...I.E. WABASHA TO
CLAYTON. WILL MONITOR RADAR TRENDS TO SEE IF EXPANSION EASTWARD IS
NEEDED.
UPDATE ISSUED AT 1040 AM CST SAT FEB 15 2014
16Z WATER VAPOR LOOP SHOWS A FAIRLY IMPRESSIVE SHORTWAVE DIGGING
SOUTHEAST THROUGH SOUTHWEST MN...HEADING TOWARDS NORTH CENTRAL
IOWA. AHEAD OF THE SHORTWAVE...COMBINATION OF DPVA...ISENTROPIC
LIFT AND SOME NEGATIVE EPV FLOWING IN HAS HELPED TO INVIGORATE A
BAND OF SNOW ALONG/WEST OF I-35. IT TOOK A LITTLE BIT TO OVERCOME
LOW LEVEL SATURATION ISSUES...SEEN ON THE 12Z MPX SOUNDING...BUT
ONCE IT DID VISIBILITIES QUICKLY DROPPED FROM 10 MILES TO
BASICALLY 1/4 MILE. SOME SNOWFALL REPORTS RECEIVED THUS FAR
COURTESY OF NWS CHANHASSEN WERE 2.5 INCHES IN REDWOOD FALLS AND
1.5 INCHES IN MANKATO. WITH THESE SITES STILL SNOWING...LOOKS LIKE
THEY COULD ACCUMULATE A QUICK 2 TO 4 INCHES.
16.11Z AND 16.12Z RAP13 -12 TO -18C OMEGA OUTPUT HAS LINED UP WELL
WITH THE HEAVY RATES COMING OUT OF THIS SNOW BAND. FOLLOWING OUT
IN TIME WOULD SUGGEST OUR FAR WESTERN 8 COUNTIES...BASICALLY
MOSTLY ALONG AND WEST OF HIGHWAY 52...WOULD BE IMPACTED. GIVEN THE
VISIBILITIES AND SNOWFALL REPORTS RECEIVED THUS FAR...HAVE ISSUED
AN ADVISORY. ANOTHER FACTOR CONSIDERED TOO IS WINDS...WHICH HAVE
BEEN SUSTAINED AROUND 15 KT IN THE ADVISORY AREA WITH GUSTS OF
20-25 KT. THIS WILL EASILY BLOW AND DRIFT SOME OF THE SNOW AROUND.
MEANWHILE...FARTHER TO THE EAST...LOOKS LIKE MOST LOCATIONS EAST
OF THE MISSISSIPPI RIVER ARE GOING TO GET MISSED BY MUCH OF THE
SNOW. THIS IS BECAUSE THE TRACK OF THE SHORTWAVE IS HEADING
SOUTHEAST...VERSUS EAST. THEREFORE...HAVE TRIMMED POPS AND SNOW
AMOUNTS A LITTLE.
&&
.SHORT TERM...(TODAY THRU SUNDAY)
ISSUED AT 252 AM CST SAT FEB 15 2014
EVEN IN THIS FAST MOVING FLOW...TIMING OF SHORT TERM RIDGE EARLY
THIS MORNING HAS LED TO ANOTHER SUB ZERO START. FAVORED COLD SPOTS
OF WESTERN AND CENTRAL WISCONSIN /CRANBERRY COUNTY/ IN THE 10 TO 20
BELOW.
MEANWHILE UPSTREAM...MULTITUDE OF SHORT WAVE TROUGHS WAIT IN THE
WINGS WITH PRECIPITATION THREAT TODAY AND AGAIN MONDAY. FOCUS
REMAINS ON THOSE SYSTEMS AND POTENTIAL IMPACT.
STRONG JET RIDING OVER INTERMOUNTAIN UPPER RIDGE HELPING TO PUSH
NEXT SHORT WAVE TROUGH INTO THE REGION TODAY. CLOUDS ALREADY ON THE
INCREASE WITH PATCHY PRECIPITATION NOTED OVER THE NORTHERN PLAINS.
DECENT MID LEVEL Q-G FORCING SHOULD CREATE ENOUGH LIFT FOR EXPANSION
OF SNOW AS WAVE APPROACHES BUT HAVE SLOWED TIMING A LITTLE TO MAINLY
THIS AFTERNOON...MOVING ACROSS RIVER BY EVENING. GENERAL SNOW
AMOUNTS SHOULD BE IN 1 TO 2 INCH RANGE WITH SHORT DURATION SNOW.
COULD BE SOME BANDS IN SNOW LEADING TO HIGHER SNOW RATES AND SHORT
TERM IMPACT TO TRAVEL BUT EVEN WITH A LITTLE WIND...SEEMS TO BE A
SUB ADVISORY TYPE OF DAY.
ALTHOUGH LOOKING LESS AND LESS LIKELY...STILL SEE SUBTLE HINTS OF
LOSS OF ICE IN TOP DOWN APPROACH LATE IN DAY ACROSS MAINLY NORTHEAST
IOWA. SOME LIFT FOR A SHORT PERIOD AS WELL SO COULD NOT COMPLETELY
RULE OUT A SHORT PERIOD OF FREEZING DRIZZLE.
BETWEEN SYSTEMS...SUNDAY LOOKS QUIET AS SHORT TERM UPPER RIDGE
PASSES THROUGH. SEASONABLY COOL DAY ON TAP.
.LONG TERM...(SUNDAY NIGHT THROUGH FRIDAY)
ISSUED AT 252 AM CST SAT FEB 15 2014
ACTIVE...LOWER AMPLITUDE FLOW WILL LEAD TO ANOTHER SHORT WAVE TROUGH
COMING IN SUNDAY NIGHT AND MONDAY. A BIT STRONGER DYNAMICS WITH THIS
ONE...DEEPER Q-G FORCING AND EVEN HINTS OF DUAL JET STRUCTURE WITH
MORE DIVERGENCE ALOFT TO HELP SUPPORT STRONG LIFT. WARMER AIRMASS
AND MORE MOISTURE TO WORK WITH AS WELL...SO ADVISORY CERTAINLY
POSSIBLE HEADING INTO THE MONDAY MORNING COMMUTE.
WHILE MODELS IN DECENT AGREEMENT WITH TIMING...SUBTLE DIFFERENCES IN
TEMPERATURE PROFILES NOTED. GFS/ECMWF REMAIN A BIT COLDER WITH ALL
SNOW...WHILE NAM REMAINS THE WARMER MODEL WITH SOME SLEET OR BRIEF
FREEZING RAIN SCENARIOS IN PARTS OF NORTHEAST IOWA INTO SOUTHWEST
WISCONSIN AROUND DAYBREAK MONDAY. MODELS ARE TRENDING COLDER AND
STRONGER DYNAMICS SUPPORT THAT IDEA. EVEN IN WARMEST SCENARIO...
TEMPERATURES ALOFT MAY ONLY WARM A DEGREE OR TWO ABOVE FREEZING
ALLOWING FOR BRIEF SLEET PERIOD AT BEST SO SNOW ONLY SCENARIO SEEMS
BEST TO GO WITH. AGAIN...FAST MOVING SYSTEM BUT SNOWFALL RATES COULD
BE IMPRESSIVE FOR 2 TO 3 HOURS MONDAY MORNING. 2 TO 5 INCHES...WITH
HIGHER AMOUNTS ALONG AND NORTH OF INTERSTATE 94 IN WISCONSIN.
CERTAINLY EXPECTING TRAVEL PROBLEMS FOR HIGHWAYS AND SCHOOLS.
TUESDAY AND WEDNESDAY LOOK QUIET AS ANOTHER SMALL SCALE RIDGE MOVES
IN.
STRONG JET PUSHING INTO PACIFIC NORTHWEST WILL KICK ANOTHER TROUGH
INTO THE MIDWEST BY WEDNESDAY NIGHT THOUGH WITH MEDIUM RANGE
GUIDANCE CONSISTENT IN SURGE OF WARMER AIR AND INFLUX OF MOISTURE BY
LATER HALF OF NEXT WEEK. A LITTLE EARLY TO NAIL DOWN PRECIPITATION
TYPES BUT COULD BE LOOKING AT SNOW IN NORTHWEST HALF OF FORECAST
AREA WITH ALL RAIN TO THE SOUTHEAST. STILL CONCERNED THAT HIGHER QPF
AND MELTING COULD LEAD TO SOME FLOODING ISSUES BUT WILL HAVE TO WAIT
TO SEE HOW THIS SYSTEM EVOLVES IN FORECAST GUIDANCE NEXT FEW DAYS.
TRACK OF SURFACE LOW AND DEFORMATION ZONE WITH HEAVIEST SNOW COULD
ALSO TRACK ACROSS THE REGION SO PLENTY TO KEEP AN EYE ON IN LATER
PERIODS.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY)
ISSUED AT 1135 AM CST SAT FEB 15 2014
BAND OF SNOW AHEAD OF LOW PRESSURE IN EASTERN SOUTH DAKOTA IS
RAPIDLY APPROACH RST. VISIBILITIES QUICKLY DROP...FROM VFR TO
LIFR/VLIFR AS THE SNOW MOVES IN. HAVE TRENDED THE 18Z TAF FOR RST
IN THAT FASHION...WITH CEILINGS ALSO DROPPING FROM VFR TO
IFR/LIFR. LOOKS LIKE THE PERIOD OF HEAVIER SNOW SHOULD BE SHORT
LIVED AT RST...WITH VISIBILITIES AND CEILINGS CLIMBING TO IFR BY
22Z...MVFR BY 00Z AND VISIBILITIES TO VFR BY 02Z. MEANWHILE...AT
LSE...SNOW BAND LOOKS TO MOVE IN AROUND 20Z WITH VISIBILITIES
FALLING TO IFR AND CEILINGS TO MVFR. APPEARS THE SNOW SHOULD NOT
BE AS HEAVY AT LSE BASED ON MODEL FORCING FORECASTS...THUS HAVE
ONLY WENT AS LOW AS TEMPORARILY LIFR WITH VISIBILITIES BETWEEN
21-24Z. EXPECT VISIBILITIES TO CLIMB TO VFR BY 03Z AS THE SNOW
DIMINISHES.
LOOK FOR TOTAL SNOWFALL ACCUMULATIONS AT RST OF 3...MAYBE 4
INCHES...AND AT LSE OF UP TO 2 INCHES.
AN MVFR STRATUS DECK WILL LIKELY LINGER AT BOTH TAF SITES THROUGH
MUCH OF THE NIGHT...SCATTERING OUT TOWARDS 09-12Z AS DRIER AIR
FLOWS IN FROM THE NORTHWEST.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...WINTER WEATHER ADVISORY UNTIL 6 PM CST THIS EVENING FOR MNZ086-
087-094-095.
IA...WINTER WEATHER ADVISORY UNTIL 6 PM CST THIS EVENING FOR
IAZ008>010-018-019-029.
&&
$$
UPDATE...AJ
SHORT TERM...SHEA
LONG TERM...SHEA
AVIATION...AJ
AREA FORECAST DISCUSSION
NWS MILWAUKEE/SULLIVAN WI
1109 AM CST SAT FEB 15 2014
.UPDATE...SHORTWAVE CONTINUES TO APPROACH FROM SW MN. UPPER JET
DRIVING IN AND ENHANCING SNOWS ACROSS NRN MO/SRN IA. MODELS HAVE
BEEN CONSISTENT IN KEEPING BETTER UPPER JET RELATED FORCING
LARGELY TO OUR SOUTH. DEF ZONE SNOWS PROGGD MORE TO OUR NORTH. AS
THE ELONGATED NORTH/SOUTH BAND ACROSS IA SHIFTS EAST IT WILL BE
AIDED BY DIFFERENTIAL CYCLONIC VORTICITY ADVECTION OF THE
SHORTWAVE. MODEL QPF SOLUTIONS SHOWING A SPLIT WITH THE ABOVE
SCENARIO LEAVING SRN WI WITH A RELATIVE MIN BETWEEN THE BETTER
FORCING AREAS. THE HRRR SHOWS DRAMATIC WEAKENING OF PRECIP WITH
TIME WHILE GFS/NAM/ECMWF SHOW THIS AS WELL WITH STILL A FEW
HUNDREDTHS OF LIQUID. SO GIVEN THE CONSENSUS OF THE MODEL DATA
THIS POINTS TOWARDS GOING LINE TO WEAKEN A BIT WITH TIME. SO IT
LOOKS LIKE A QUICK HITTING EVENT FROM MID AFTERNOON THROUGH EARLY
EVENING WITH AN INCH AT MOST FOR ALL OF SRN WI.
PC
&&
.AVIATION/18Z TAFS/...QUICK HITTING SNOW EVENT FROM MID AFTERNOON
INTO EARLY EVENING. LOOKING AT AN INCH OR LESS IN MOST AREAS AS
MODELS WEAKEN CURRENT VIGOROUS BAND ACROSS IA TRENDING HEAVIER
SNOW NORTH AND SOUTH OF SRN WI. WILL CONTINUE TO MONITOR THESE
TRENDS TO ENSURE WEAKENING PANS OUT AS SUGGESTED BY MODELS. EXPECTING
CIGS AND VSBYS TO LOWER TO AT LEAST MVFR LEVELS WITH SOME IFR
VSBYS LIKELY ESP IN SC WI WHERE BAND MAY STILL BE A BIT BETTER
ORGANZIED. LOW LEVEL RH PROGS SUGGEST LOWER CLOUD DECK LINGERS
INTO SUNDAY MORNING.
PC
&&
.PREV DISCUSSION... /ISSUED 339 AM CST SAT FEB 15 2014/
TODAY AND TONIGHT...FORECAST CONFIDENCE...HIGH
MODELS CONTINUE TO DELAY MOVING LIGHT SNOW INTO SRN WITH THE SHORT
TERM/HI RESOLUTION MODELS KEEPING THE FORECAST AREA DRY THROUGH 21Z
AND BARELY REACHING A DELLS...MADISON TO JANESVILLE LINE BY 00Z.
OTHER OPERATIONAL MODELS IN LINE WITH KEEPING AT LEAST THE LAKESHORE
COUNTIES SNOW FREE UNTIL 00Z WITH SNOW TRACKING ACROSS REGION WITH
BEST 500-300MB DIFFERENTIAL VORTICITY ADVECTION...AS ISENTROPIC
UPGLIDE AHEAD OF SHORT WAVE WEAKENS AS IT MOVES INTO SRN WI AND RE-
FOCUSES TO THE SOUTH OVER ILLINOIS.
WILL HAVE A SHARP GRADIENT TO POPS LATE THIS AFTERNOON TO MATCH
TIGHT CONDENSATION PRESSURE DEFICIT ON ISENTROPIC FORECASTS THAT
CORRELATE WELL WITH COLUMN SATURATION ON FORECAST SOUNDINGS.
CATEGORICAL POPS EVERYWHERE THIS EVENING...WITH ABOUT A 3-HOUR LONG
PERIOD OF LIGHT TO MODERATE SNOW. QPF GRADIENT AS WELL...WITH AROUND
0.10 INCH IN THE SW TAPERING TO AROUND 0.05 IN THE NORTHEAST AND
EAST. 15:1 TO 16:1 SNOW LIQUID RATIOS YIELD AROUND 1 INCH OVER MOST
OF THE CWA WITH 1.5 TO 2 INCH AMOUNTS IN THE SOUTHWEST THIRD.
MODELS HAVE 925MB THERMAL RIDGE OVER FORECAST AREA AT 00Z...TO
DIFFERING MAGNITUDES. FORECAST SOUNDINGS ALL AGREE MIXING ONLY UP TO
BETWEEN 935 TO 930 MB SO WENT COOLER THAN WHAT 925MB WOULD INDICATE
WITH HIGHS IN THE TEENS TO AROUND 20...SIMILAR TO PREVIOUS FORECAST.
NAM SLOWER WITH COLD ADVECTION OVERNIGHT AND IS 2C TO 3C WARMER THAN
GFS/ECMWF AT 925 MB AT 12Z SUNDAY. LINGERING CLOUDS SUPPORT BLENDED
TEMPS WHICH GIVE LOWS IN THE SINGLE DIGITS ABOVE INLAND...AND 10 TO
13 ABOVE ALONG THE LAKE.
SUNDAY AND MONDAY...FORECAST CONFIDENCE...HIGH
SHOULD BE DRY SUNDAY AS HIGH PRESSURE BRIEFLY SLIDES THROUGH.
NORTHEAST WINDS OFF LAKE MICHIGAN WILL PROBABLY KEEP SKIES MOSTLY
CLOUDY THROUGH AT LEAST THE MORNING IN THE EAST. HIGHS WILL REMAIN
ABOUT 10 DEGREES BELOW NORMAL.
LOW PRESSURE IS EXPECTED TO APPROACH THE AREA SUNDAY NIGHT...THEN
MOVE THROUGH ON MONDAY. MODELS HAVE CONTINUED TO SHOW A COLDER
SOUTHERN TRACK OF THE SFC LOW...SO REMOVED ANY MENTION OF MIXED
PRECIPITATION AS ONLY SNOW IS EXPECTED AT THIS POINT. STRONG WARM
ADVECTION IS EXPECTED THROUGH THIS EVENT...SO LOOKS LIKE PLENTY OF
LIFT. TEMPERATURES AND THICKNESS VALUES SUGGEST LIQUID TO SNOW
RATIOS OF 10-12 TO 1. STILL A DECENT RANGE IN QPF AMONG
MODELS...SO USED CONSENSUS APPROACH...RESULTING IN SNOW AMOUNTS
OF 4 TO 5 INCHES.
TUESDAY AND WEDNESDAY...FORECAST CONFIDENCE...MEDIUM
MODELS IN DECENT AGREEMENT WITH A SPELL OF MILDER TEMPS FOR THE
MIDDLE OF THE WEEK. LOOKS MAINLY DRY TUESDAY AND WEDNESDAY WITH MID
TO UPPER 30S FOR HIGH TEMPS.
THURSDAY AND FRIDAY...FORECAST CONFIDENCE...LOW
THE GFS REMAINS SIMILAR TO TUE/WED WITH TEMPS FOR THURSDAY...WITH
SOME LIGHT RAIN MOVING THROUGH. THE ECMWF ON THE OTHER HAND STILL SHOWS
A STRONG LOW LIFTING NORTHEAST THROUGH THE WESTERN FORECAST
AREA...WITH STRONG SOUTHERLY FLOW BRINGING UP A DECENT AMOUNT OF
RAIN AND TEMPS UP AROUND 50. CONTINUED TO SPLIT THE
DIFFERENCE...WITH HIGHS NEAR 40...SIMILAR TO THE CANADIAN
SOLUTION.
DRY WEATHER IS EXPECTED FRIDAY...AS A COLDER AIRMASS MOVES IN
BEHIND THE DEPARTING LOW. PRETTY GOOD SPREAD IN HIGH TEMPS BETWEEN
THE GFS IN THE MID TO UPPER 20S AND ECMWF IN THE MID TO UPPER 30S.
SPLIT THE DIFFERENCE IN TEMPS FOR NOW.
AVIATION/12Z TAFS/...CLEAR SKIES WITH SURFACE TO 850 MB RIDGING AND
LIGHT WINDS. WILL SEE VFR CONDITIONS AT KMSN UNTIL MID TO LATE
AFTERNOON AND 00Z AT EASTERN TAF SITES. HIGH TO MID-LEVEL CLOUDS
SPREAD IN AHEAD OF APPROACHING SHORT WAVE TROUGH...WITH SNOW AND
MVFR CIGS/VSBYS WITH OCCASIONAL IFR VSBYS REACHING KMSN AROUND
21Z...KUES BETWEEN 22Z AND 23Z AND KMKE AND KENW AROUND 00Z.
EXPECTING AROUND A 3-4 HOUR LONG PERIOD OF SNOW WITH ACCUMULATIONS
AROUND 1 INCH AT ALL TAF SITES. MVFR CIGS WILL HOLD IN AT ALL SITES
THROUGH THE REMAINDER OF THE FORECAST. NOT MUCH WIND SO
BLOWING/DRIFTING WILL NOT BE A BIG PROBLEM.
&&
.MKX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
LM...NONE.
&&
$$
TODAY/TONIGHT AND AVIATION/MARINE...REM
SUNDAY THROUGH FRIDAY...DDV