Forecast Discussions mentioning any of
"HRRR" "RAP" "RR" "RUC13" "RUC" received at GSD on 04/17/14
AREA FORECAST DISCUSSION
NWS DENVER/BOULDER CO
921 PM MDT WED APR 16 2014
.UPDATE...
ISSUED AT 858 PM MDT WED APR 16 2014
BEST SNOW IS OVER THE MOUNTAINS...FOOTHILLS SOUTH OF I-70 AND PARK
COUNTY. THERE ARE SOME RETURNS ON THE RADAR OVER THE PLAINS...BUT
VERY LITTLE SEEMS TO BE HITTING THE GROUND. MADE SOME MINOR
ADJUSTMENTS.
&&
.SHORT TERM...(THIS EVENING THROUGH THURSDAY)
ISSUED AT 350 PM MDT WED APR 16 2014
SHORTWAVE TROUGH CURRENTLY MOVING ACROSS COLORADO. MOISTURE AND
WEAK ASCENT BEGINNING TO INCREASE AGAIN...THOUGH BEST ASCENT OVER
SOUTHWEST COLORADO. SOME SHOWERS ONGOING SOUTH OF THE PALMER
DIVIDE...BEGINNING TO CREEP NORTHWARD. AIRMASS SLIGHTLY UNSTABLE
WITH CAPES AROUND 100 J/KG ACROSS SOUTHERN MOUNTAINS...SOUTHERN
FOOTHILLS AND PARK COUNTY. WINDS HAVE BEGUN TO DECREASE ACROSS THE
PLAINS...BECOMING A BIT MORE EASTERLY. TROUGH STILL EXPECTED TO
MOVE EAST ACROSS COLORADO TONIGHT. MOISTURE TO CONTINUE TO SPREAD
NORTHWARD OVER THE AREA. THOUGH THE MAIN BATCH OF MID LEVEL ASCENT
EXPECTED TO SLIDE ACROSS SOUTHERN COLORADO...THERE WILL BE ENOUGH
ASCENT OVER THE AREA FOR AT LEAST A SLIGHT CHANCE OF SHOWERS. BEST
CHANCE FOR SHOWERS STILL LOOKS TO BE ACROSS THE MOUNTAINS AND
FOOTHILLS SOUTH OF INTERSTATE 70 AND ALONG THE PALMER DIVIDE.
LATEST MODELS CONTINUE TO GENERATE THE BULK OF THE QPF SOUTH OF
THE CWA. BUT LOW LEVEL EAST SOUTHEAST FLOW WILL HELP WITH LOCAL
UPSLOPE ACROSS SOUTH PARK AND SOUTHERN FOOTHILLS. LATEST RAP SHOWS
LIGHT QPF IN THIS AREA AND EXTENDING INTO THE CENTRAL MOUNTAINS.
WILL KEEP THE HIGHER POPS IN THIS AREA WITH LIGHT ACCUMULATIONS.
LOWER POPS FURTHER NORTH WITH WEAK MID LEVEL ASCENT. SYSTEM PULLS
AWAY OVERNIGHT WITH FLOW ALOFT BECOMING NORTHWEST. DRIER AND MORE
SUBSIDENT AIRMASS SPREADS INTO AREA. THREAT FOR PRECIPITATION TO
DECREASE AFTER MIDNIGHT AND SHOULD COME TO AN END TOWARDS MORNING.
MAY BE A FEW LINGERING FLURRIES OR LIGHT SNOW ACROSS LINCOLN
COUNTY. ON THURSDAY...NORTHWEST FLOW TO PREVAIL OVER THE AREA AS
UPPER TROUGH MOVES INTO THE NORTHERN AND CENTRAL PLAINS STATES.
UPPER RIDGE TO BUILD ACROSS THE GREAT BASIN...AND WILL SPREAD
WARMER AIR INTO THE AREA. MODELS SHOW SOME WRAP AROUND MOISTURE
MOVING INTO THE PLAINS DURING THE AFTERNOON. LATEST NAM AND GFS
GENERATE SOME LIGHT SHOWERS FAR NORTHEAST CORNER. AIRMASS LOOKS
FAIRLY SUBSIDENT...WILL NOT INCLUDE ANY SHOWERS AT THIS POINT.
TEMPERATURE AND THICKNESS PROGS SHOW HIGHS WARMING INTO THE LOWER
60S ACROSS THE PLAINS.
.LONG TERM...(THURSDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 303 PM MDT WED APR 16 2014
THE MAIN FEATURE FOR THIS FORECAST WILL BE A WEAK...SLOW MOVING
UPPER TROUGH MOVING OUT OF THE DESERT SOUTHWEST FROM FRIDAY
AFTERNOON THROUGH SUNDAY. AHEAD OF THE TROUGH...A WARM UPPER RIDGE
WILL BE OVER THE STATE FRIDAY AFTERNOON WITH WARM TEMPERATURES NAMMAINLY
DRY CONDITIONS ACROSS THE FORECAST AREA. THERE MAY BE A FEW
AFTERNOON SHOWERS OVER THE MOUNTAINS...BUT THE MAIN MOISTURE FROM
THE SOUTHWEST U.S. UPPER TROUGH IS NOT EXPECTED TO ARRIVE UNTIL
LATER ON SATURDAY. BY SATURDAY AFTERNOON...AS THE BROAD UPPER
TROUGH APPROACHES THE STATE...SHOWERS WILL BE MORE WIDESPREAD ON
SATURDAY AND SUNDAY AFTERNOONS. THE AIRMASS SHOULD REMAIN WARM
ENOUGH THAT CONVECTIVE ACTIVITY WILL CONTAIN SOME THUNDERSTORMS.
BOTH DAYS WILL BE FAIRLY SIMILAR AS THE TROUGH SLOWLY PROGRESSES
ACROSS THE STATE. AFTERNOON CONVECTION ON SATURDAY AND SUNDAY HAS
A FAIR CHANCE OF EXTENDING WELL OUT ONTO THE PLAINS EACH AFTERNOON
DUE TO THE BROAD NATURE OF THE UPPER TROUGH. THE FIRST HALF OF
NEXT WEEK WILL THEN BE WARMER AND DRIER AS STRONG UPPER RIDGING
DEVELOPS OVER THE DESERT SOUTHWEST. ALL MODELS ARE IN PRETTY GOOD
AGREEMENT THROUGH NEXT WEEK WITH THE GENERAL TIMING OF THE
MOVEMENT OF THE SOUTHWEST U.S. TROUGH AND THEN DEVELOPMENT OF THE
STRONG UPPER RIDGING. TEMPERATURES SHOULD BE WELL ABOVE NORMAL FOR
THE MONDAY THROUGH WEDNESDAY TIMEFRAME.
&&
.AVIATION...(FOR THE TAFS THROUGH 06Z THURSDAY EVENING)
ISSUED AT 858 PM MDT WED APR 16 2014
THE EASTERLIES AT DIA HAVE DECREASED AND ARE TRYING TO GO TO
SOUTHEASTERLIES. STILL BELIEVE THEY`LL BE DRAINAGE BEFORE
SUNRISE. DOUBT IF CEILINGS WILL GET BELOW 5000 AGL BEFORE THEY GO
AWAY. WILL LEAVE VCSH IN UNTIL AROUND 09Z.
&&
.BOU WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...RJK
SHORT TERM...D-L
LONG TERM...DANKERS
AVIATION...RJK
AREA FORECAST DISCUSSION
NWS PUEBLO CO
856 PM MDT WED APR 16 2014
.UPDATE...
ISSUED AT 849 PM MDT WED APR 16 2014
UPDATED LATEST TEMPS AND MADE MINOR CHANGES TO TEMPS OVERNIGHT.
ADJUSTED SOME SNOWFALL AMOUNTS FOR THE REST OF TONIGHT.
&&
.SHORT TERM...(THIS EVENING THROUGH THURSDAY)
ISSUED AT 254 PM MDT WED APR 16 2014
...HEAVY WET SNOW FOR THE SOUTHEASTERN MOUNTAINS TONIGHT...
RAPIDLY EVOLVING STORM SYSTEM NOW IS MOVING INTO WRN CO THIS
AFTERNOON. ALREADY AM SEEING SOME BANDED PRECIP...IN THE FORM OF
SHRA...DEVELOP OVER EL PASO COUNTY. DEWPOINTS STILL PRETTY LOW OVER
THE PLAINS...WHICH WILL HELP COOL THINGS OFF THIS EVE AS WET BULB
IS REACHED IN HEAVIER PRECIP. EXPECT PRECIP TO EXPAND AND INTENSIFY
THROUGH THE AFTERNOON...REACHING ITS PEAK FROM 00Z THROUGH 06Z
TONIGHT.
A COUPLE OF RECENT TRENDS ARE MAKING FOR A RATHER TRICKY FORECAST
FOR THE SHORT TERM. RECENT GUIDANCE IS CONSIDERABLY WARMER THAN IT
HAD BEEN A COUPLE DAYS AGO...WITH H7 TEMPS ONLY FALLING TO MINUS
5 OR 6 AS OPPOSED TO THE MINUS 10 OR LOWER FROM EARLIER MODEL RUNS.
THIS IS POINTING AT THE SNOW LEVELS GENERALLY STAYING AT OR
ABOVE 6000 FEET TONIGHT. BUT DEPENDING ON EVENTUAL STRENGTH AND
TIMING...WOULD NOT BE SURPRISED TO SEE SNOW FALLING AT THE LOWER
ELEVATIONS. JUST NOT EXPECTING MUCH IF ANY ACCUMULATION BELOW 6K
FEET...EXCEPT MAYBE ON GRASSY SURFACES. THE WINTER WX ADVISORY FOR
THE SRN I-25 CORRIDOR WILL BE A PARTICULAR CHALLENGE SINCE
ELEVATIONS FROM WALSENBURG TO TRINIDAD ARE GENERALLY IN THE 6000-
6500 FOOT RANGE. SO...EVEN A SLIGHT SHIFT IN THE LOW LEVEL
TEMPERATURES THIS EVE COULD MAKE THE DIFFERENCE BETWEEN WET PAVEMENT
AND A FEW INCHES OF SLUSH. HAVE GENERALLY PLAYED THE MIDDLE ROAD OF
MODEL CONSENSUS...WHICH HAS SNOW LEVELS AT OR ABOVE THAT ELEVATION
FOR THE EARLY EVE. BUT...HIGHER TRRN TO THE WEST AND CLOSER TO
SPANISH PEAKS COULD SEE SIGNIFICANT WET SNOW...MORE THAN SIX INCHES
FOR SOME AREAS.
OTHER ISSUE IS THE RECENT TREND TOWARDS THE HEAVIEST ACCUMS FALLING
OVER THE SRN ZONES...THE WETS AND SRN SANGRES GENERALLY SOUTH OF
HIGHWAY 50. THE HRRR AND LOCAL HI-RES WRF...FOR EXAMPLE...KEEP
MOST OF THE HEAVY PRECIP SOUTH OF THE PIKES PK REGION. THE NAM
AND RUC..LOWER RES...KEEP HEAVY PRECIP OVER THE PIKES PEAK REGION.
GIVEN THE POOR PERFORMANCE OF THE HIGHER RES SOLUTIONS SO FAR...AM
INCLINED TO KEEP WITH AT LEAST MODERATE ACCUMS FOR PIKES
PEAK...ALTHOUGH IT SEEMS REASONABLE THAT SRN AND ERN SIDES WILL GET
A BIT MORE THIS EVE. MODELS ARE HITTING THE SRN SANGRES AND HIGHER
WETS PRETTY HARD THROUGH 06-08Z TONIGHT. HAVE CONSIDERED UPGRADING
FOR THOSE ZONES...BUT SINCE THE LIQUID-SNOW RATIOS WILL BE HIGHER
GIVEN THE WARMER LOW-LEVEL THERMAL PROFILE...EXPECT THE MORE
SIGNIFICANT ACCUMS TO BE PRETTY HIGH UP AND SPOTTY. SO...ADVISORIES
LOOK GOOD FOR NOW BUT WILL HAVE TO FOLLOW THE SHORT TERM TRENDS
PRETTY CAREFULLY.
WILL SEE THE SYSTEM CLEAR OUT GRADUALLY FROM N TO S AFTER MIDNIGHT.
COULD EVEN SEE SOME CLEARING BY SUNRISE ON THURSDAY. BALANCE OF
THURSDAY LOOKS PRETTY NICE...WITH TEMPS REBOUNDING TO THE UPPER 50S
OVER THE PLAINS BY AFTERNOON...AND INCREASING AMOUNTS OF SUN. ROSE
.LONG TERM...(THURSDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 254 PM MDT WED APR 16 2014
NEXT SYSTEM WILL BE MOVING INTO THE REGION OVER THE WEEKEND BRINGING
A RETURN OF ACTIVE WEATHER IN THE EXTENDED. CLOSED LOW MOVES IN
FROM THE PACIFIC...ACROSS SOUTHERN CA AND INTO THE DESERT SOUTHWEST
THROUGH FRIDAY NIGHT. MOISTURE INCREASES...PARTICULARLY ACROSS
WESTERN AREAS ON FRIDAY...SO SHOULD SEE ISOLATED TO SCATTERED RAIN
AND HIGHER ELEVATION SNOW SHOWERS OVER THE MOUNTAINS WITH SOME
ISOLATED EMBEDDED THUNDERSTORMS POSSIBLE DURING THE AFTERNOON. ANY
SNOWFALL ACCUMULATIONS LOOKS LIGHT THROUGH THIS PERIOD...AND
CONFINED TO THE HIGHER ELEVATIONS.
THIS SYSTEM WILL GRADUALLY FILL AS IT MOVES INTO THE FOUR CORNERS
REGION ON SATURDAY THEN ACROSS CO THROUGH SUNDAY MORNING AS AN OPEN
TROF. PRECIPITATION WILL INCREASE ACROSS THE SOUTHWEST MOUNTAINS
FRIDAY NIGHT...THEN SPREAD ACROSS ALL OF THE MOUNTAINS AND ADJACENT
PLAINS ON SATURDAY. WITH COOLING ALOFT...LAPSE RATES STEEPEN...AND
A COLD FRONT...THOUGH IT IS NOT ALL THAT COOL BEHIND IT...WILL MOVE
THROUGH THE SOUTHEAST PLAINS DURING THE AFTERNOON. NAM12 IS THE
FARTHEST SOUTH WITH THE FRONT SAT AFTERNOON SHOWING EASTERLY WINDS
ACROSS THE PLAINS AND DEW POINTS INCREASING INTO THE 40S TO AROUND
50 NEAR THE EASTERN BORDER BY 00Z. GFS IS A TAD SLOWER...WITH
NORTHERLY WINDS DROPPING THROUGH THE I-25 CORRIDOR DURING THE
AFTERNOON...AND DEW POINTS IN THE 30S THROUGH THE AFTERNOON. ECMWF
IS FAIRLY SIMILAR TO THE GFS...THOUGH A JUST A TAD MOISTER. EITHER
WAY...SNOW LEVELS WILL BE ON THE HIGH SIDE AGAIN...PROBABLY AROUND
9.5-10KFT...SO BELOW THIS ELEVATION WILL HAVE TO MONITOR THE BURN
SCARS CLOSELY FOR RAINFALL...ESPECIALLY THE WALDO. FOR NOW
THOUGH...THINK THAT GFS PROBABLY HAS THE BEST HANDLE...AND ANY
LOCALLY HEAVIER PRECIPITATION AMOUNTS WILL BE SPOTTY AS MODEL CAPE
VALUES ARE NOT ALL THAT HIGH. ISOLATED THUNDERSTORMS WILL ALSO
SPREAD ACROSS THE SOUTHEAST PLAINS SATURDAY AFTERNOON AND
EVENING...THOUGH RAINFALL AMOUNTS LOOK FAIRLY LIGHT AT THIS POINT
AS HIGHER CAPE REMAINS WELL TO THE EAST.
THIS SYSTEM SLOWLY EXITS EASTERN CO ON SUNDAY...SO AFTER
PRECIPITATION WINDS DOWN OVERNIGHT...ENOUGH INSTABILITY AND RESIDUAL
MOISTURE WILL BE PRESENT FOR ANOTHER ROUND OF ISOLATED THUNDERSTORMS
SUNDAY AFTERNOON. THESE LOOK A LITTLE SPOTTIER IN COVERAGE.
DRY WEATHER RETURNS FOR EARLY NEXT WEEK...THEN THE FORECAST WILL
REVOLVE AROUND TRACK OF THE NEXT UPPER LOW WHICH DROPS INTO THE
GREAT BASIN...THEN EVENTUALLY LIFTS OUT TO THE NORTH OF THE FORECAST
AREA WED. THIS WILL PUT MOST OF SOUTH CENTRAL AND SOUTHEAST COLORADO
UNDER STRONG SOUTHWEST FLOW ALOFT WITH THE POTENTIAL FOR CRITICAL
FIRE WEATHER CONDITIONS DEVELOPING ESPECIALLY BY WEDNESDAY.
DEPENDING ON THE CONDITIONS OF FUELS...MAY NEED SOME FIRE WEATHER
HIGHLIGHTS FOR THIS DAY. OTHERWISE...DRY LINE WILL BE LURKING NEAR
THE CO/KS BORDER DURING THE EARLY TO MIDDLE PART OF NEXT WEEK.
TRENDS IN THE LATEST OPERATIONAL GFS AND ECWMF...SEEM TO SUGGEST A
MORE NORTHERN TRACK AND LESS OF A PERSISTENT MERIDIONAL FLOW EARLY
NEXT WEEK...SO THESE LATEST RUNS KEEP THE DRYLINE JUST TO OUR
EAST. HOWEVER...THERE ARE STILL SOME RATHER LARGE DIFFERENCES IN
THE EXTENDED MODELS FOR WED AS GFS SHOWS MORE ENERGY DROPPING
SOUTHWARD INTO THE BASE OF THE TROF ACROSS THE GREAT BASIN WHICH
EC DOES NOT HAVE...SO JURY IS STILL OUT. EITHER WAY...SHOULD BE AN
ACTIVE PERIOD THROUGH NEXT WEEK. -KT
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z THURSDAY AFTERNOON)
ISSUED AT 254 PM MDT WED APR 16 2014
EXPECT PRECIP TO EXPAND IN COVERAGE AND INTENSITY THROUGH
THIS EVE. KCOS WILL BE ON THE NRN SIDE OF THE HEAVIER BANDS OF
PRECIP...BUT THERE IS A GOOD CHANCE IT WILL GO DOWN TO IFR CIGS
AND/OR VIS FOR THE 00-06Z TIME FRAME. KPUB WILL FOLLOW SUIT...ABOUT
AN HOUR OR SO LATER AS PRECIP SLOWLY SHIFTS TO THE SOUTH. SNOW LEVELS
CONTINUE TO LOOK TO BE AROUND 5500-6000 FEET FOR MOST OF THE AREA.
KALS COULD SEE SOME SPOTTY PRECIP TONIGHT...BUT THE GREATER IMPACT
WILL BE ALONG AND E OF THE SANGRES...WETS...AND PIKES PEAK. CLEARING
CONDITIONS THU MORNING COULD LEAD TO SOME BRIEF FG OR BR FOR ANY
AREAS THAT SEE PRECIP EARLY ON. ROSE
&&
.PUB WATCHES/WARNINGS/ADVISORIES...
WINTER WEATHER ADVISORY UNTIL 4 AM MDT THURSDAY FOR COZ072>075-
079>082-087-088.
&&
$$
UPDATE...28
SHORT TERM...ROSE
LONG TERM...KT
AVIATION...ROSE
AREA FORECAST DISCUSSION
NWS MIAMI FL
133 PM EDT TUE APR 15 2014
.AVIATION...
MESOSCALE GUIDANCE HAS BEEN LESS THAN IMPRESSIVE IN TERMS OF
SHOWER COVERAGE FOR THIS AFTERNOON...BUT STILL APPEARS ISOLATED/SCATTERED
ACTIVITY WILL FORM DURING MID/LATE- AFTERNOON HOURS. VCSH
CONTINUED IN TAFS TO ACCOUNT FOR THIS. VFR CONDITIONS SHOULD
PREVAIL BUT LOCALIZED RESTRICTIONS PLAUSIBLE IN/NEAR CONVECTION.
THUNDER CANT BE RULED OUT BUT PROB IS QUITE LOW. SSE WINDS OF
15-25 KTS WILL BECOME SSW LATER THIS AFTERNOON. THE WEST LATE THIS
EVENING AS COLD FRONT MOVES IN.
WINDS TURN NORTHERLY WEDNESDAY MORNING...AND MODELS INDICATED LOW
STRATUS COULD INVADE FROM NORTH AND HOLD OVER SOUTH FLORIDA INTO
AFTERNOON. ELECTED TO NOT GO AGGRESSIVE THIS FAR OUT...BUT BKN035
INTRODUCED BEGINNING ROUGHLY AT SUNRISE.
&&
.PREV DISCUSSION... /ISSUED 950 AM EDT TUE APR 15 2014/
UPDATE...
SOMEWHAT OF A FORECAST DILEMMA THIS MORNING CONCERNING THE CHANCE
OF AFTERNOON THUNDERSTORMS. A COLD FRONT CURRENTLY IS MOVING
ACROSS THE FLORIDA PANHANDLE WITH A BAND OF SHOWERS AND
THUNDERSTORMS AHEAD OF THE FRONT THROUGH THE BIG BEND AREA AND
INTO THE NORTHEAST GULF OF MEXICO. PLENTY OF SUN IS OCCURRING
ACROSS SOUTH FLORIDA WHICH WILL PROVIDE SUFFICIENT DIURNAL HEATING
TODAY AS THE FRONT APPROACHES CENTRAL FLORIDA LATE THIS AFTERNOON.
HOWEVER, HEREIN LIES THE QUESTION. THE 12Z MFL SOUNDING CONTINUES
TO SHOW A QUITE STABLE LAYER OF AIR WITH THE BASE AT ABOUT 10K AND
EXTENDING UPWARDS TO ABOUT 15K. THIS IS GOING TO BE A INHIBITING
FACTOR WITH ANY SHOWER ACTIVITY HAVING A TOUGH TIME BREAKING
THROUGH THIS STABLE CAP. HOWEVER, DUE TO THE SUFFICIENT HEATING
THAT WILL BE TAKING PLACE AND MAXIMUM AFTERNOON TEMPERATURES
APPROACHING THE 90 DEGREE MARK BY 2-3 PM EDT THIS COULD PROVIDE
THE NECESSARY BUOYANCY TO PENETRATE THE STABLE LAYER. SOME OF THE
HIGH RESOLUTION SHORT TERM COMPUTER MODELS DO SHOW SOME CONVECTIVE
DEVELOPMENT AT THAT TIME AND THEN MOVING TOWARDS THE EAST COAST IN
THE GENERAL SOUTHWEST STEERING FLOW. STILL, THE HRRR WHICH IS VERY
RELIABLE FOR SOUTH FLORIDA ONLY SHOWS ISOLATED DEVELOPMENT AND
MAINLY ALONG THE PALM BEACH COASTAL AREA. THE FORTUNATE ASPECT OF
THE HRRR IS THAT IT UPDATES EVERY HOUR SO WILL BE TAKING A CLOSE
LOOK AT ITS SOLUTIONS OVER THE NEXT SEVERAL HOURS AND MAY NEED TO
SCALE BACK POPS AT LEAST OVER THE WESTERN PORTIONS OF THE
PENINSULA.
KOB
PREV DISCUSSION... /ISSUED 722 AM EDT TUE APR 15 2014/
SHORT TERM...
ONE OR TWO OF THE STORMS COULD EVEN BECOME STRONG LATE THIS
AFTERNOON INTO THIS EVENING MAINLY AROUND THE LAKE OKEECHOBEE
REGION AND THE EAST COAST METRO AREAS WHERE PERHAPS BETTER
CONVERGENCE WILL BE. THE PRIMARY IMPACTS FROM THE STRONG STORMS
WILL BE GUSTY WINDS...AS A LOW LEVEL JET OF 40 TO 50 KNOTS WILL BE
MOVING THROUGH THE AREA. SO WILL MENTION THIS IN THE HWO MORNING
PACKAGE.
DRIER AIR WILL THEN BE WORKING INTO SOUTH FLORIDA FOR LATE
TONIGHT. HOWEVER...THE DRY AIR WILL NOT LAST LONG AS THE FRONT
WILL STALL OVER THE FLORIDA KEYS LATE TONIGHT BEFORE MOVING BACK
NORTHWARD THROUGH SOUTH FLORIDA WEDNESDAY AFTERNOON INTO WEDNESDAY
NIGHT. THIS WILL BRING BACK SOME MOISTURE ALONG WITH A CHANCE OF
SHOWERS TO THE AREA. SO WILL CONTINUE THE ISOLATED TO SCATTERED
SHOWERS OVER SOUTH FLORIDA FOR WEDNESDAY AFTERNOON INTO WEDNESDAY
NIGHT.
THE LATEST MEDIUM RANGE MODELS ARE NOW SHOWING LOW PRESSURE
DEVELOPING OVER THE NORTHERN GULF OF MEXICO LATE THIS WEEK AND
MOVING EAST ACROSS NORTH FLORIDA BEFORE MOVING INTO THE WESTERN
ATLANTIC WATERS THIS WEEKEND. THIS WILL PUSH THE FRONT BACK
SOUTHWARD THROUGH SOUTH FLORIDA FRIDAY NIGHT. SO THE TROPICAL
MOISTURE WILL REMAIN IN PLACE FOR LATE THIS WEEK BEFORE DRIER AIR
WORKS INTO SOUTH FLORIDA FOR THIS WEEKEND. SO WILL CONTINUE THE
SCATTERED POPS OVER SOUTH FLORIDA LATE THIS WEEK ALONG WITH A
THREAT OF THUNDERSTORMS. THE EASTER WEEKEND OVER SOUTH FLORIDA
LOOKS DRY NOW. THEREFORE...THE POPS HAVE BEEN REMOVED OVER SOUTH
FLORIDA THIS WEEKEND ALONG WITH SKIES MOSTLY CLEAR.
LONG TERM...
LOW PRESSURE WILL CONTINUE TO MOVE FURTHER EAST INTO THE ATLANTIC
WATERS EARLY NEXT WEEK ALLOWING FOR HIGH PRESSURE TO BUILD INTO
THE SOUTHEASTERN UNITED STATES. THIS WILL ALLOW FOR AN EASTERLY
WIND FLOW OVER THE AREA EARLY NEXT WEEK. SO SOME LOW LEVEL
MOISTURE SHOULD RETURN TO SOUTH FLORIDA EARLY NEXT WEEK LEADING TO
A FEW SHOWERS. SO WILL CONTINUE THE SLIGHT CHANCE OF SHOWERS OVER
SOUTH FLORIDA FOR EARLY NEXT WEEK.
MARINE...
THE WINDS TODAY WILL BE FROM THE SOUTH/SOUTHWEST DIRECTION AT 15
KNOTS OR LESS BEFORE SWINGING TO A NORTHERLY DIRECTION LATE
TONIGHT INTO WEDNESDAY. THE WIND DIRECTION WILL CONTINUE TO SWING
TO A EASTERLY DIRECTION WEDNESDAY NIGHT INTO THURSDAY WITH SPEEDS
AT 15 KNOTS OR LESS. THERE WILL ALSO BE A SMALL NORTHEAST SWELL
WORKING INTO THE SOUTH FLORIDA WATERS FROM THE NORTH WEDNESDAY
NIGHT INTO THURSDAY.
THE SEAS SHOULD REMAIN BELOW 7 FEET IN BOTH THE ATLANTIC AND GULF
WATERS TODAY INTO WEDNESDAY...BUT COULD GET TO 7 FEET IN PALM
BEACH WATERS ON THURSDAY DUE TO THE SMALL NORTHEAST SWELLS.
CLIMATE...
THE HIGHS AROUND 90 DEGREES TODAY OVER THE EAST COAST METRO AREAS
WILL BE GETTING CLOSE TO THE RECORD HIGHS FOR THIS DATE WHICH ARE:
CITIES FORECAST HIGHS RECORD HIGHS
MIA 90 93 - 1975
FLL 90 93 - 2001
PBI 90 93 - 1999
&&
.PRELIMINARY POINT TEMPS/POPS...
WEST PALM BEACH 67 80 71 84 / 30 30 30 40
FORT LAUDERDALE 70 81 74 85 / 30 30 30 30
MIAMI 71 82 73 85 / 30 30 30 40
NAPLES 67 84 68 88 / 20 20 20 50
&&
.MFL WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
AM...NONE.
GM...NONE.
&&
$$
SHORT TERM...30/KOB
LONG TERM....54/BNB
AVIATION...23/SK
AREA FORECAST DISCUSSION
NWS MIAMI FL
950 AM EDT TUE APR 15 2014
.UPDATE...
SOMEWHAT OF A FORECAST DILEMMA THIS MORNING CONCERNING THE CHANCE
OF AFTERNOON THUNDERSTORMS. A COLD FRONT CURRENTLY IS MOVING
ACROSS THE FLORIDA PANHANDLE WITH A BAND OF SHOWERS AND
THUNDERSTORMS AHEAD OF THE FRONT THROUGH THE BIG BEND AREA AND
INTO THE NORTHEAST GULF OF MEXICO. PLENTY OF SUN IS OCCURRING
ACROSS SOUTH FLORIDA WHICH WILL PROVIDE SUFFICIENT DIURNAL HEATING
TODAY AS THE FRONT APPROACHES CENTRAL FLORIDA LATE THIS AFTERNOON.
HOWEVER, HEREIN LIES THE QUESTION. THE 12Z MFL SOUNDING CONTINUES
TO SHOW A QUITE STABLE LAYER OF AIR WITH THE BASE AT ABOUT 10K AND
EXTENDING UPWARDS TO ABOUT 15K. THIS IS GOING TO BE A INHIBITING
FACTOR WITH ANY SHOWER ACTIVITY HAVING A TOUGH TIME BREAKING
THROUGH THIS STABLE CAP. HOWEVER, DUE TO THE SUFFICIENT HEATING
THAT WILL BE TAKING PLACE AND MAXIMUM AFTERNOON TEMPERATURES
APPROACHING THE 90 DEGREE MARK BY 2-3 PM EDT THIS COULD PROVIDE
THE NECESSARY BUOYANCY TO PENETRATE THE STABLE LAYER. SOME OF THE
HIGH RESOLUTION SHORT TERM COMPUTER MODELS DO SHOW SOME CONVECTIVE
DEVELOPMENT AT THAT TIME AND THEN MOVING TOWARDS THE EAST COAST IN
THE GENERAL SOUTHWEST STEERING FLOW. STILL, THE HRRR WHICH IS VERY
RELIABLE FOR SOUTH FLORIDA ONLY SHOWS ISOLATED DEVELOPMENT AND
MAINLY ALONG THE PALM BEACH COASTAL AREA. THE FORTUNATE ASPECT OF
THE HRRR IS THAT IT UPDATES EVERY HOUR SO WILL BE TAKING A CLOSE
LOOK AT ITS SOLUTIONS OVER THE NEXT SEVERAL HOURS AND MAY NEED TO
SCALE BACK POPS AT LEAST OVER THE WESTERN PORTIONS OF THE
PENINSULA.
KOB
&&
.PREV DISCUSSION... /ISSUED 722 AM EDT TUE APR 15 2014/
SHORT TERM...
A COLD FRONT OVER THE FLORIDA PANHANDLE WILL CONTINUE TO MOVE
SOUTHWARD DOWN THE SUNSHINE STATE TODAY AND THROUGH SOUTH FLORIDA
THIS EVENING. THE WINDS OVER SOUTH FLORIDA TODAY WILL BE FROM
SOUTH/SOUTHWEST DIRECTION AHEAD OF THE FRONT ALLOWING TEMPERATURES
TO WARM UP INTO THE MID TO UPPER 80S OVER MOST AREAS...EXCEPT
AROUND 90 ALONG THE EAST COAST METRO AREAS. AT THE SAME
TIME...MOISTURE WILL ALSO BE WORKING INTO SOUTH FLORIDA FROM THE
SOUTH LEADING TO SCATTERED SHOWERS AND EVEN SOME THUNDERSTORMS
OVER SOUTH FLORIDA THIS AFTERNOON INTO THIS EVENING.
ONE OR TWO OF THE STORMS COULD EVEN BECOME STRONG LATE THIS
AFTERNOON INTO THIS EVENING MAINLY AROUND THE LAKE OKEECHOBEE
REGION AND THE EAST COAST METRO AREAS WHERE PERHAPS BETTER
CONVERGENCE WILL BE. THE PRIMARY IMPACTS FROM THE STRONG STORMS
WILL BE GUSTY WINDS...AS A LOW LEVEL JET OF 40 TO 50 KNOTS WILL BE
MOVING THROUGH THE AREA. SO WILL MENTION THIS IN THE HWO MORNING
PACKAGE.
DRIER AIR WILL THEN BE WORKING INTO SOUTH FLORIDA FOR LATE
TONIGHT. HOWEVER...THE DRY AIR WILL NOT LAST LONG AS THE FRONT
WILL STALL OVER THE FLORIDA KEYS LATE TONIGHT BEFORE MOVING BACK
NORTHWARD THROUGH SOUTH FLORIDA WEDNESDAY AFTERNOON INTO WEDNESDAY
NIGHT. THIS WILL BRING BACK SOME MOISTURE ALONG WITH A CHANCE OF
SHOWERS TO THE AREA. SO WILL CONTINUE THE ISOLATED TO SCATTERED
SHOWERS OVER SOUTH FLORIDA FOR WEDNESDAY AFTERNOON INTO WEDNESDAY
NIGHT.
THE LATEST MEDIUM RANGE MODELS ARE NOW SHOWING LOW PRESSURE
DEVELOPING OVER THE NORTHERN GULF OF MEXICO LATE THIS WEEK AND
MOVING EAST ACROSS NORTH FLORIDA BEFORE MOVING INTO THE WESTERN
ATLANTIC WATERS THIS WEEKEND. THIS WILL PUSH THE FRONT BACK
SOUTHWARD THROUGH SOUTH FLORIDA FRIDAY NIGHT. SO THE TROPICAL
MOISTURE WILL REMAIN IN PLACE FOR LATE THIS WEEK BEFORE DRIER AIR
WORKS INTO SOUTH FLORIDA FOR THIS WEEKEND. SO WILL CONTINUE THE
SCATTERED POPS OVER SOUTH FLORIDA LATE THIS WEEK ALONG WITH A
THREAT OF THUNDERSTORMS. THE EASTER WEEKEND OVER SOUTH FLORIDA
LOOKS DRY NOW. THEREFORE...THE POPS HAVE BEEN REMOVED OVER SOUTH
FLORIDA THIS WEEKEND ALONG WITH SKIES MOSTLY CLEAR.
LONG TERM...
LOW PRESSURE WILL CONTINUE TO MOVE FURTHER EAST INTO THE ATLANTIC
WATERS EARLY NEXT WEEK ALLOWING FOR HIGH PRESSURE TO BUILD INTO
THE SOUTHEASTERN UNITED STATES. THIS WILL ALLOW FOR AN EASTERLY
WIND FLOW OVER THE AREA EARLY NEXT WEEK. SO SOME LOW LEVEL
MOISTURE SHOULD RETURN TO SOUTH FLORIDA EARLY NEXT WEEK LEADING TO
A FEW SHOWERS. SO WILL CONTINUE THE SLIGHT CHANCE OF SHOWERS OVER
SOUTH FLORIDA FOR EARLY NEXT WEEK.
AVIATION...
SCATTERED SHOWERS...AND PERHAPS A THUNDERSTORM OR TWO...ARE LIKELY
TO DEVELOP THIS AFTERNOON...ESPECIALLY AT KAPF AND KPBI. DUE TO
LOW TS RISK...FEEL VCSH IS SUFFICIENT...WITH VFR CONDITIONS MOST
PREVALENT. SOUTH WINDS WILL INCREASE TODAY AND BECOME GUSTY THIS
AFTERNOON. AS COLD FRONT MOVES IN OVERNIGHT...WINDS WILL SHIFT TO
WEST.
MARINE...
THE WINDS TODAY WILL BE FROM THE SOUTH/SOUTHWEST DIRECTION AT 15
KNOTS OR LESS BEFORE SWINGING TO A NORTHERLY DIRECTION LATE
TONIGHT INTO WEDNESDAY. THE WIND DIRECTION WILL CONTINUE TO SWING
TO A EASTERLY DIRECTION WEDNESDAY NIGHT INTO THURSDAY WITH SPEEDS
AT 15 KNOTS OR LESS. THERE WILL ALSO BE A SMALL NORTHEAST SWELL
WORKING INTO THE SOUTH FLORIDA WATERS FROM THE NORTH WEDNESDAY
NIGHT INTO THURSDAY.
THE SEAS SHOULD REMAIN BELOW 7 FEET IN BOTH THE ATLANTIC AND GULF
WATERS TODAY INTO WEDNESDAY...BUT COULD GET TO 7 FEET IN PALM
BEACH WATERS ON THURSDAY DUE TO THE SMALL NORTHEAST SWELLS.
CLIMATE...
THE HIGHS AROUND 90 DEGREES TODAY OVER THE EAST COAST METRO AREAS
WILL BE GETTING CLOSE TO THE RECORD HIGHS FOR THIS DATE WHICH ARE:
CITIES FORECAST HIGHS RECORD HIGHS
MIA 90 93 - 1975
FLL 90 93 - 2001
PBI 90 93 - 1999
&&
.MFL WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
AM...NONE.
GM...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS TOPEKA KS
406 AM CDT Tue Apr 15 2014
.SHORT TERM...(Today and Tonight)
Issued at 302 AM CDT TUE APR 15 2014
Extreme fire danger conditions return for portions of north
central Kansas followed by strong winds and warmer temperatures.
Departing upper trough continues to track eastward over the Mid
Atlantic region as quiet and cold conditions have settled across
northeast Kansas this morning. A quick rebound in temperatures is on
tap for today as variable winds shift to the south, advecting warmer
air into the area. A surface trough, currently positioned over
northern Colorado, deepens eastward this afternoon, increasing
southwesterly winds 15 to 20 MPH west to east after 1 PM across
north central areas. Sounding profilers depict strong mixing through
800 MB across the area, lowering dewpoint temperatures into the
lower 20s and upper teens. Please refer to the fire weather
discussion below for additional details. Have issued a Red Flag
Warning for low humidity and gusty winds for this afternoon into the
early evening across portions of north central Kansas. Highs today
are expected to recover into the upper 50s and low 60s by late
afternoon underneath sunny skies.
Southerly winds increase between 20 and 25 mph sustained this
evening as a strong 70 kt low level jet develops coincident with
the upper trough over the northern plains. The increased mid level
clouds from the passing system and the mixed boundary layer should
keep overnight lows much warmer in the lower 40s.
.LONG TERM...(Wednesday through Monday)
Issued at 302 AM CDT TUE APR 15 2014
Early Wednesday morning, a 60 kt low level jet will be oriented
across the forecast area. While this jet will weaken and gradually
slide to the east, morning mixing will likely bring some rather
strong wind gusts to the surface by 10 AM or so...potentially in
the 45 to 50 mph range. Have not quite gone that high in the
forecast given high cloud cover and a fairly rapid decrease in
wind speeds by late morning, but it is possible. Expect a rather
warm day on Wednesday although a cold front will make its way into
the northwest half of the area by late afternoon. Will likely have
a thermal ridge very near the frontal boundary which would focus
the warmest temps near and just ahead of the front. With the wind,
warm temps, and relatively dry low levels, will have fire weather
concerns for Wed as well...more details in the fire weather
section below.
The front will continue to slowly progress through the area
overnight, although it`s expected to be a dry front through
midnight or so. Beyond midnight, and incoming short wave trough
will interact with the frontal zone as it becomes nearly
stationary near/just south of the forecast area. This will result
in an enhanced area of vertical motion spreading east across KS,
focused mainly across the southern 2/3 of the forecast area.
Expect this to persist through the day on Thursday before the wave
passes overhead on Thursday evening and subsidence takes over.
Expect rather persistent light precipitation with this system. THE
ECMWF is on the dry side of model guidance in terms of total QPF
while it seems that the NAM/GFS are probably picking up on some of
the expected mesoscale lift enhancements and producing slightly
higher amounts. Dry advection from the north will provide a sharp
cutoff to the precipitation, and have reduced POPs in northern KS
with some potential for areas near the Nebraska border to end up
dry if the dry advection is strong enough. Precip type will be
predominantly rain although there seems to be a period early
Thursday morning when it could change to snow especially on the
northern fringes of the precip area. Accumulation appears unlikely
at this time.
Will see a nice warm-up for the weekend as upper ridging returns
to the area on the heels of the Thursday system. Expect moisture
advection to bring dewpoints well into the 50s by Saturday in
advance of the next upper trough. This system has trended slightly
slower over recent model runs but otherwise fairly consistent in
bringing another chance for widespread precipitation to the area.
Do not expect much instability with this storm system but could
still see periods of thunder. This looks to be a pretty widespread
rain with the best chances Saturday night into Sunday, but do not
expect particularly heavy amounts. Should also see continued warm
temperatures throughout the weekend with highs in the upper 60s,
and even warmer behind the system on Monday as little to no cold
advection is expected behind the trough.
&&
.FIRE WEATHER...(This Afternoon and Wednesday)
Issued at 4 AM CDT TUE APR 15 2014
Expect southerly winds over north central Kansas to quickly increase
after 12 PM as a surface trough rapidly deepens over the central and
northern plains. 850 MB winds increase from near 10 KTS to over 30
KTS by 3 PM this afternoon, mixing dewpoint temperatures down into
the upper teens. Decided to use a combination of the latest RAP and
NAM, with a lean towards the RAP as previous events trended drier
than forecast. These extreme fire danger conditions with the
continuation of critical fuels has prompted a Red Flag Warning after
1 PM for Cloud, Republic, and Ottawa counties. Very high fire danger
conditions exist across the remainder of the CWA this afternoon into
the early evening. It is important to note the southerly winds will
increase through the evening and overnight hours with gusts near 30
MPH and sustained speeds between 20 and 25 mph.
For Wednesday, should start the day windy with lower than normal
sunrise RH. While there will be some modest moisture increase
with the southerly winds, expect it to be shallow. Deep mixing by
late morning to early afternoon will pull drier air to the surface
along with potentially very strong wind gusts. At the same time,
the incoming cold front will bring a zone of much lighter winds as
far east as Manhattan by mid afternoon although RH may be lowest
near the front. Behind the front, temperatures will not be much
cooler and winds will increase out of the northwest. All-in-all,
expect the most volatile combination of strong wind and low RH to
be southeast of an Abilene to Seneca line through the day...many
of the areas to see the highest rainfall totals this past weekend.
Current MinRH forecast is in the 22 to 27 percent range but could
see it ending up a bit lower while winds in this area gust to 40+
mph.
&&
.AVIATION...(For the 06Z TAFs through 06Z Tuesday Night)
Issued at 1146 PM CDT MON APR 14 2014
VFR conditions expected through the taf period.
&&
.TOP WATCHES/WARNINGS/ADVISORIES...
FREEZE WARNING until 9 AM CDT this morning FOR KSZ008>012-
020>024-026-034>040-054>056-058-059.
&&
$$
SHORT TERM...Bowen
LONG TERM...Barjenbruch
AVIATION...Sanders
AREA FORECAST DISCUSSION
NWS GOODLAND KS
1030 PM MDT MON APR 14 2014
.SHORT TERM...(THIS EVENING THROUGH TUESDAY)
ISSUED AT 1252 PM MDT MON APR 14 2014
EARLY AFTERNOON WV IMAGERY AND RAP UPPER LEVEL ANALYSIS SHOW TROUGH
EXTENDING FROM GREAT LAKES ACROSS THE CENTRAL/SOUTHERN PLAINS AND
RIDGE BUILDING OVER WESTERN US. AT THE SURFACE HIGH PRESSURE IS IN
PLACE ACROSS EASTERN COLORADO/WESTERN KS WITH N-NW GRADIENT OVER
KS/NE SUPPORTING GUSTY WINDS OVER OUR CWA. SNOW PACK HAS RETREATED
OVER MUCH OF OUR CWA...WHILE VIS SATELLITE INDICATES IT HOLDING ON
OVER PARTS OF NE COLORADO AND ALONG KS/NE STATE LINE WHERE AROUND
INCHES OF SNOW FELL MONDAY AND MONDAY NIGHT.
ON THE BACK SIDE OF DEPARTING UPPER LEVEL TROUGH H3 JET STEAM IS
MOVING ACROSS NORTHERN PLAINS. STEEP LOW/MID LEVEL LAPSE RATES HAVE
DEVELOPED WITH SHALLOW COOL LAYER AND DAYTIME HEATING AND HAS LED TO
CU FIELD DEVELOPING OVER THE SOUTHERN PART OF OUR CWA. AS NOSE OF JET
MOVES ACROSS CENTRAL NEBRASKA THERE MAY BE ENOUGH FORCING ALONG WITH
THIS WEAKLY UNSTABLE MID LAYER FOR A FEW SPRINKLES TO MOVE INTO THE
NORTHEAST CORNER OF OUR CWA...OTHERWISE WE ARE ONLY LOOKING AT A
PERIOD OF MID LEVEL CU OVER OUR CWA THIS AFTERNOON. IF THERE IS A
BETTER SHOWER WE COULD SEE A FLURRY INSTEAD OF SPRINKLE
THROUGH...BUT I DIDN`T SEE A REASON TO GET THAT CUTE CONSIDERING
CONFIDENCE IS ALREADY LOW ON PRECIP REACHING THE GROUND IN OUR NE
CWA.
ANOTHER HARD FREEZE IS EXPECTED TONIGHT...THOUGH THERE WILL BE SOME
MODERATION OF THE AIR MASS ALOFT AS HIGH PRESSURE SHIFTS EAST AND
W-SW WINDS DEVELOP LATE TONIGHT.
MONDAY...CONTINUE MODERATION OF THE AIR MASS IS EXPECTED WITH
DAYTIME HIGHS REACHING SEASONAL VALUES IN THE 60S ACROSS THE CWA.
SNOW PACK COULD STILL IMPACT LOCATIONS IN THE NORTH...HOWEVER WITH
SW WINDS COMING FROM SNOW FREE LOCATIONS WE SHOULD SEE A QUICK
MELTING OF SNOW. MAIN CONCERN FOR MONDAY WILL BE POTENTIAL FOR RED
FLAG CONDITIONS WITH WINDY CONDITIONS DEVELOPING EARLY IN THE WEST
AND GOOD MIXING SUPPORTING LOWER TD VALUES ACROSS THE SOUTH.
MODEL OUTPUT GENERALLY SUPPORTS A DECREASING TREND IN THE WEST IN
THE AFTERNOON AS GRADIENT SHIFTS EAST...SO THERE MAY ONLY BE A
SMALL WINDOW FOR WIND/RH CROSSOVER. OF COURSE THERE IS ALSO THE
QUESTION OF WHETHER FUELS WILL BE CURED AFTER RECENT PRECIP
(ESPECIALLY OVER LOCATIONS WITH LINGERING SNOW PACK). WITH TOO
MUCH UNCERTAINTY I DECIDED AGAINST ISSUANCE OF FIRE WEATHER WATCH
AT THIS TIME.
.LONG TERM...(TUESDAY NIGHT THROUGH MONDAY)
ISSUED AT 237 PM MDT MON APR 14 2014
MODEL SOLUTIONS REMAIN IN CLOSE AGREEMENT THROUGH THE END OF THE
WORK WEEK AND THEN BEGIN TO DIVERGE THROUGH THE WEEKEND AS AN
UPPER TROUGH MOVES ACROSS THE NORTHERN PLAINS IN THE NORTHERN
BRANCH OF THE UPPER FLOW AND A SHORT WAVE TROUGH EMBEDDED IN THE
SOUTHERLY BRANCH TRIES TO COME INTO PHASE WITH THE NORTHERLY
BRANCH.
THE GFS REMAINS THE MORE PROGRESSIVE SOLUTION WHILE THE ECMWF
LAGS BEHIND NEARLY 24 HOURS. THIS IS PROVING TO BE TROUBLESOME
WITH THE TIMING OF THE PRECIPITATION THAT IS POSSIBLE BETWEEN A
LATE FRIDAY TO LATE SATURDAY TIME FRAME. HAVE GONE WITH SOME KIND
OF BLENDED COMPROMISE SOLUTION FOR THE FRIDAY THROUGH SUNDAY TIME
PERIOD WITH RAIN SHOWERS TRANSITIONING TO A FEW THUNDERSTORMS AND
BACK TO RAIN SHOWERS ON SATURDAY AND SATURDAY NIGHT. EXPECT DRY
AND WARMER CONDITIONS THROUGH THE REMAINDER OF THE WEEKEND INTO
THE BEGINNING OF NEXT WEEK AS A LARGE RIDGE AMPLIFIES OVER THE
WESTERN UNITED STATES AND MOVES EAST OVER THE ROCKIES AND HIGH
PLAINS REGION.
BACKTRACKING TO THE MID-WEEK SYSTEM...
EXPECT RAIN TO DEVELOP EAST OF THE ROCKIES LATE WEDNESDAY AND
TRANSITION TO SNOW AS IT SPREADS ACROSS THE FORECAST AREA
WEDNESDAY NIGHT. EXPECT A TRANSITION BACK TO RAIN DURING THE DAY
ON THURSDAY...BUT MAY END UP STAYING MORE SNOW THROUGH THURSDAY
MORNING IF TEMPERATURES REMAIN COLDER AND WET BULB ZERO
TEMPERATURES ARE COLDER AS THEY WERE WITH THE LAST SYSTEM THAT
DEPOSITED SNOW ACROSS THE FORECAST AREA. EXPECT PRECIPITATION TO
END FROM WEST TO EAST ACROSS THE FORECAST AREA LATE IN THE DAY ON
THURSDAY. TEMPS WILL WARM BRIEFLY ON FRIDAY AND SATURDAY AHEAD OF
THE NEXT SYSTEM.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT)
ISSUED AT 1030 PM MDT MON APR 14 2014
KGLD...VFR CONDITIONS THROUGH THE PERIOD. WEST/SOUTHWEST WINDS
AROUND 10KTS AT TAF ISSUANCE WILL INCREASE A BIT TOWARD 15KTS
AROUND 09Z AND CONTINUE THROUGH 14Z. AFTER 14Z WINDS EXPECTED TO
INCREASE WITH SUSTAINED SPEEDS OF 15-20KTS WITH GUSTS NEAR 30KTS
THROUGH 02Z BEFORE DIMINISHING TO AROUND 12KTS THROUGH THE REST OF
THE TAF PERIOD. ONLY HIGH CLOUDINESS EXPECTED...MAINLY DURING THE
AFTERNOON AND EVENING.
KMCK...VFR CONDITIONS THROUGH THE PERIOD. WEST/SOUTHWEST WINDS
AROUND 06KTS EXPECTED THROUGH 16Z. AFTER 16Z SOUTHWEST WINDS
AROUND 15KTS WITH GUSTS NEAR 25KTS EXPECTED THROUGH 02Z BEFORE
BACKING TO THE SOUTH AROUND 11KTS FOR THE REMAINDER OF THE TAF
PERIOD. ONLY HIGH CLOUDINESS EXPECTED...MAINLY DURING THE
AFTERNOON AND EVENING.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
SHORT TERM...DR
LONG TERM...LOCKHART
AVIATION...99
AREA FORECAST DISCUSSION
NWS WAKEFIELD VA
634 PM EDT TUE APR 15 2014
.SYNOPSIS...
A STRONG COLD FRONT MOVES OFF THE COAST THIS EVENING. CANADIAN
HIGH PRESSURE BUILDS IN FROM THE NORTHWEST TONIGHT AND SETTLES
OVER THE MID ATLANTIC AND NORTHEAST WEDNESDAY THROUGH FRIDAY.
&&
.NEAR TERM /UNTIL 6 AM WEDNESDAY MORNING/...
COLD FRONT CRNTLY MOVING ACROSS SERN VA/NRN NC ERLY THIS EVE WITH
A NRLY SOLID BAND OF MDT-HVY SHWRS/TSTRMS ALONG IT. HAVING TO HAND
EDIT THE TEMP/DP TEMP GRID AS MODELS NOT HANDLING THE 20+ DEGREE
TMP DROP IN 1 HOUR BEHIND THE FROPA THAT WELL. ADJUSTED GRIDS PER
LATEST RADAR TRENDS. INCREASED POPS TO CATEGORICAL ALL AREAS NEXT
1-3 HRS AS DEEP MOISTURE CONTINUES TO FEED INTO THIS SYSTM EVEN
BEHIND THE FRNT. STILL EXPECT THIS SYSTM TO SWEEP OFFSHORE AFTER
MIDNIGHT WITH FAIRLY RAPID CLRG.
STRONG NORTH WINDS ARE FORECAST ALONG THE COAST. FOR A FEW HOURS
THIS EVENING...WINDS OF 25 TO 35 MPH WITH HIGHER GUSTS ARE
EXPECTED OVER PORTIONS OF HAMPTON ROADS AND CURRITUCK COUNTY NORTH
CAROLINA THIS EVENING. THESE WINDS ARE ALSO INDICATED IN THE
VIRGINIA PORTION OF THE LOWER EASTERN SHORE. STRONGEST WINDS WILL
BE NEAR THE COAST AND IN AREAS OF HAMPTON ROADS DIRECTLY EXPOSED
TO THE CHESAPEAKE BAY.
LOW TEMPERATURES TONIGHT DROP TO BETWEEN 28 AND 32 OVER INLAND
RURAL AREAS. A FREEZE WARNING IS IN EFFECT FOR MOST OF EASTERN
VIRGINIA EXCLUDING SOUTHSIDE HAMPTON ROADS AND THE LOWER VIRGINIA
EASTERN SHORE. THE FREEZE WARNING IS ALSO IN EFFECT FOR THE MD
EASTERN SHORE EXCEPT FOR OCEAN CITY AND FOR NORTHAMPTON COUNTY
NORTH CAROLINA.
&&
.SHORT TERM /6 AM WEDNESDAY MORNING THROUGH FRIDAY/...
HIGH PRESSURE SETTLES OVER THE MID ATLANTIC AND NORTHEAST DURING THE
SHORT TERM. DUE TO N TO NW WINDS AND COLD TEMPERATURES ALOFT...
CLOUDS FROM STREAMERS ARE EXPECTED OVER THE CHESAPEAKE BAY
AND EASTERN PORTIONS OF SOUTH SIDE HAMPTON ROADS ON WEDNESDAY...
ESPECIALLY IN THE MORNING. TEMPERATURES WILL REMAIN COOL WEDNESDAY
AND THURSDAY WITH HIGHS MAINLY IN THE 50S. ON WEDNESDAY...
TEMPERATURES MAY GET NO HIGHER THAN THE MID TO UPR 40S ALONG THE
COAST INCLUDING THE NORFOLK AND VIRGINIA BEACH AREA AND THE LOWER
EASTERN SHORE. LOWS THURSDAY MORNING AGAIN ARE FORECAST TO FALL TO
AROUND 30 OVER INTERIOR PORTIONS. SOME FROST IS POSSIBLE AS WELL
INCLUDING LOCATIONS THAT ONLY FALL TO THE LOW TO MID 30S. ANY NEEDED
HEADLINES WILL BE DEFERRED TO LATER SHIFTS.
TEMPERATURES WARM A BIT FRIDAY WITH HIGHS IN THE LOWER 60S OVER
INTERIOR AREAS. THERE WILL BE A SLIGHT CHANCE FOR RAIN TOWARD THE
COAST...ESPECIALLY OVER SOUTHEAST VIRGINIA AND NORTHEAST NORTH
CAROLINA.
&&
.LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/...
AN AREA OF SFC LOW PRESSURE IS EXPECTED TO DEVELOP ON A STALLED
BOUNDARY OFF THE SOUTHEAST COAST FRI NIGHT. THE LOW SHOULD TRACK NE
WELL OFF THE CAROLINA COAST ON SAT. THIS FEATURE MAY BRING A FEW
RAIN SHOWERS TO FAR SE VA/NE NC DURING THIS TIMEFRAME.
MEANWHILE...AN UPPER LEVEL TROUGH OVER THE UPPER MIDWEST WILL SWING
INTO THE ERN GREAT LAKES FRI NIGHT AND SKIRT ACROSS NRN VA ON SAT. A
WEAK SFC LOW WILL BE ASSOCIATED WITH THIS FEATURE AND MAY BRING A
BRIEF ROUND OF SHOWERS TO FAR NRN PORTIONS OF THE FA (INCLUDING THE
MD/VA EASTERN SHORE) SAT AFTN/EARLY EVENING BEFORE MOVING OFFSHORE
AND DISSIPATING. THE SFC LOW ASSOCIATED WITH THE GREAT LAKES TROUGH
IS EXPECTED TO PHASE WITH THE AFOREMENTIONED COASTAL LOW SAT
NIGHT...BUT THIS SHOULD OCCUR OVER NEW ENGLAND AND HAVE VERY LITTLE
IMPACT TO THE MID ATLANTIC STATES. SFC HIGH PRESSURE BUILDS INTO THE
REGION SUN...THEN SLIDES OFFSHORE BY SUN EVENING AS A RELATIVELY
FLAT (WEST TO EAST ORIENTED) FRONTAL BOUNDARY SAGS DOWN INTO THE
AREA MON NIGHT INTO TUE. WEAK SHORTWAVE ENERGY AND A SUBSEQUENT SFC
LOW TRAVELLING ALONG THIS BOUNDARY MAY BRING ANOTHER SHOT OF
PRECIPITATION TO THE AREA ON MON/TUE. GFS PRECIP-GENERATION AND
GENERAL MOVEMENT IS A BIT AGGRESSIVE VERSUS THE ECMWF...THEREFORE
TRIED TO SPLIT THE DIFFERENCE WITH THE POP FORECAST AND LIMITED
COVERAGE TO NO HIGHER THAN 40 PERCENT.
TEMPERATURES ARE EXPECTED TO BE STRAIGHT-FORWARD SAT NIGHT THROUGH
SUN NIGHT AS HIGH PRESSURE CROSSES THE REGION. EXPECT LOWS NEAR
NORMAL BOTH NIGHTS IN THE 40S (LOWER 50S POSSIBLE IMMEDIATE SE VA/NE
NC COASTS). HIGHS SAT/SUN RANGE FROM ROUGHLY 65 DEGREES FAR NE TO 70
DEGREES SW. AS THE FLAT FRONTAL BOUNDARY STARTS TO SAG INTO THE MID
ATLANTIC STATES MON THROUGH TUE...THE TEMP FORECAST BECOMES TRICKY
IN REGARD TO WHERE EXACTLY THE WARM SECTOR DEVELOPS. WITH PRECIP
EXPECTED TO APPROACH THE AREA ON MON...INCREASING CIRRUS SHOULD KEEP
HIGH TEMPS IN THE UPPER 60S WEST OF I-95 WITH WARMER TEMPS IN THE
LOWER 70S EAST OF I-95 (MID-UPPER 60S MD/VA EASTERN SHORE). HIGHS
TUE SHOULD BE IN THE LOWER 70S INLAND AND IN THE UPPER 60S NEAR THE
IMMEDIATE CHES BAY AND ATLANTIC COASTS. LOW TEMPERATURES AREAWIDE ON
MON/TUE NIGHT SHOULD ALSO BE WARM WITH READINGS IN THE 50S (OR ABOUT
10 DEGREES ABOVE NORMAL).
&&
.AVIATION /00Z WEDNESDAY THROUGH SUNDAY/...
INITIAL BATCH OF SHOWERS AND TSTMS HAS MOVED OFF THE COAST THIS
MORNING. THE MAIN FRONT IS STILL WELL TO THE WEST. TIMING LOOKS
QUITE GOOD ON THE NAM AND RUC SO WILL FOLLOW THEM CLOSELY. NOTICED
MAINLY VFR TO MVFR CONDITIONS AHEAD OF THE FRONT AND WILL MAINTAIN
THAT. WITH THE UPPER SYSTEM NOW ROTATING NORTHEAST TOWARD THE AREA
CAN SEE MORE SHOWERS AHEAD AND BEHIND THE FRONT DEVELOPING. WILL
CONTINUE JUST SCATTERED SHOWERS AHEAD OF THE FRONT. THE RUC MODEL
SOUNDINGS AND THE LACK OF INSTABILITY INDICATE IT WILL BE HARD FOR
ANY TSTMS TO DEVELOP. SO FOR NOW WILL NOT PUT THEM IN THE TAFS BUT
IT IS STILL POSSIBLE FOR SOME TO FORM ALONG THE FRONT AS IT
CROSSES THE AREA. BEHIND THE FRONT MODELS SHOW AT LEAST SEVER
HOURS OF MODERATE TO HEAVY SHOWERS ESPECIALLY OVER SOUTHEAST
VIRGINIA AND NORTHEAST NORTH CAROLINA. WILL GIVE A TEMPO GROUP
THERE FOR LOWER CIGS AND VSBY WITH THESE SHOWERS. CURRENTLY WEST
OF THE FRONT ONLY MVFR CONDITIONS AND CURRENT GUIDANCE ALSO GOING
MVFR. WILL KEEP PREDOMINATE CIGS AND VSBY MVFR.
IT WILL BECOME WINDY ESPECIALLY AFTER THE FRONT PASSES WITH
NORTHWEST WINDS GUSTING OVER 30 KTS AND COULD BE OVER 35 KTS IN
ORF. THESE WINDS WILL SLOWLY DIMINISH LATER TONIGHT BUT REMAIN
NORTHWEST 15 TO 20 THROUGH THE MORNING ON WEDNESDAY.
SKIES CLEAR LATE TONIGHT AND CONTINUE VFR CONDITIONS THROUGH
THURSDAY AS HIGH PRESSURE BUILDS OVER THE AREA.
&&
.MARINE...
GALE WARNGS WILL CONTINUE AS PLANNED FOR ALL WTRS TDY INTO TNGT. A
STRONG COLD FRNT IS CURRENTLY APPROACHING THE MID ATLANTIC
CST...WITH GUSTY SLY FLOW AHEAD OF THE FRNT TO BE FOLLOWED BY
STRONGER NW FLOW BEHIND THE FRNT. EXPECT GUSTS UP TO 35-40 KT OVRNGT
AS THE FRNT PUSHES OFFSHORE AND HI PRES BLDS IN FROM THE W WITH
LARGE PRES RISES. WAVES WILL RISE TO 4 TO 6 FT OVR THE BAY...AND
SEAS WILL RISE TO 6 TO 9 FT ON THE CSTL WTRS. HI PRES CONTINUES TO
BLD IN THRU WED AFTN...WHICH WILL ALLOW THE GRADIENT TO WEAKEN
SIGNIFICANTLY. STILL HAVE THE GALES ENDING AT 7 AM FOR THE
BAY/RIVERS...AND HOLDING INTO THE ERLY AFTN FOR THE CST AND SOUND.
HI PRES SLIDES NE ACRS NEW ENGLAND AND INTO THE CANADIAN MARITIMES
WED NGT THRU FRI...AS A WEAK CSTL TROF DEVELOPS OFF THE SE CST. THIS
WILL RESULT IN A PROLONGED PERIOD OF NE WINDS AND ELEVATED SEAS THRU
THE END OF THE WEEK.
&&
.AKQ WATCHES/WARNINGS/ADVISORIES...
MD...FREEZE WARNING FROM 3 AM TO 9 AM EDT WEDNESDAY FOR MDZ021>024.
NC...FREEZE WARNING FROM 3 AM TO 9 AM EDT WEDNESDAY FOR NCZ012.
VA...FREEZE WARNING FROM 3 AM TO 9 AM EDT WEDNESDAY FOR VAZ048-049-
060>085-087>094.
MARINE...GALE WARNING UNTIL 10 AM EDT WEDNESDAY FOR ANZ650-652-654.
GALE WARNING UNTIL 1 PM EDT WEDNESDAY FOR ANZ633-656-658.
GALE WARNING UNTIL 7 AM EDT WEDNESDAY FOR ANZ630>632-634>638.
&&
$$
SYNOPSIS...LSA
NEAR TERM...MPR/LSA
SHORT TERM...LSA
LONG TERM...BMD
AVIATION...LKB/JAB
MARINE...MAS
AREA FORECAST DISCUSSION
NWS WAKEFIELD VA
406 PM EDT TUE APR 15 2014
.SYNOPSIS...
A STRONG COLD FRONT WILL MOVE OFF THE COAST THIS EVENING.
CANADIAN HIGH PRESSURE BUILDS IN FROM THE NORTHWEST TUESDAY NIGHT
AND SETTLES OVER THE MID ATLANTIC AND NORTHEAST WEDNESDAY THROUGH
FRIDAY.
&&
.NEAR TERM /UNTIL 6 AM WEDNESDAY MORNING/...
UPPER AIR ANALYSIS HAS A LONG WAVE TROUGH EXTENDING FROM CANADA
ACROSS THE EASTERN GREAT LAKES TO THE SOUTHERN APPALACHIANS. A COLD
FRONT EXTENDED FROM NORTH OF NEW ENGLAND ACROSS NEW JERSEY TO
CENTRAL VIRGINIA TO GEORGIA. THESE TWO FEATURES WILL MOVE QUICKLY TO
THE EAST OF THE AREA TONIGHT. THE COLD FRONT IS EXPECTED TO EXIT THE
AREA ON THE NORTH CAROLINA COAST AROUND 02Z.
WHILE THUNDERSTORMS ARE STILL POSSIBLE...SEVERE THUNDERSTORMS LOOK
UNLIKELY AT THIS POINT. PART OF THIS IS DUE TO STABILIZATION FROM
EARLIER PRECIPITATION.
SCATTERED SHOWERS AND A FEW THUNDERSTORMS WILL CONTINUE AHEAD OF THE
FRONT AND ESPECIALLY ALONG THE FRONT. THUNDERSTORMS WILL END NEAR
THE TIME OF THE FRONTAL PASSAGE. RAIN CONTINUES IN MOST LOCATIONS
THIS EVENING...ENDING FROM WEST TO EAST LATE THIS EVENING AND EARLY
WEDNESDAY MORNING. INCLUDING RAIN THAT FELL EARLIER TODAY...MOST
LOCATIONS CAN EXPECT A TOTAL OF AROUND AN INCH OF RAIN FROM THE
EVENT WITH SOME LOCALLY HIGHER AMOUNTS.
STRONG NORTH WINDS ARE FORECAST ALONG THE COAST. FOR A FEW HOURS
THIS EVENING...WINDS OF 25 TO 35 MPH WITH HIGHER GUSTS ARE EXPECTED
OVER PORTIONS OF HAMPTON ROADS AND CURRITUCK COUNTY NORTH CAROLINA
THIS EVENING. THESE WINDS ARE ALSO INDICATED IN THE VIRGINIA PORTION
OF THE LOWER EASTERN SHORE. STRONGEST WINDS WILL BE NEAR THE COAST
AND IN AREAS OF HAMPTON ROADS DIRECTLY EXPOSED TO THE CHESAPEAKE
BAY.
TEMPERATURES DROP QUICKLY BEHIND THE FRONT WITH READINGS FALLING
INTO THE 40S WEST OF INTERSTATE 95 THIS EVENING.
LOW TEMPERATURES TONIGHT DROP TO BETWEEN 28 AND 32 OVER INLAND
RURAL AREAS. A FREEZE WARNING IS IN EFFECT FOR MOST OF EASTERN
VIRGINIA EXCLUDING SOUTHSIDE HAMPTON ROADS AND THE LOWER VIRGINIA
EASTERN SHORE. THE FREEZE WARNING IS ALSO IN EFFECT FOR THE MD
EASTERN SHORE EXCEPT FOR OCEAN CITY AND FOR NORTHAMPTON COUNTY
NORTH CAROLINA.
&&
.SHORT TERM /6 AM WEDNESDAY MORNING THROUGH FRIDAY/...
HIGH PRESSURE SETTLES OVER THE MID ATLANTIC AND NORTHEAST DURING THE
SHORT TERM. DUE TO N TO NW WINDS AND COLD TEMPERATURES ALOFT...
CLOUDS FROM STREAMERS ARE EXPECTED OVER THE CHESAPEAKE BAY
AND EASTERN PORTIONS OF SOUTH SIDE HAMPTON ROADS ON WEDNESDAY...
ESPECIALLY IN THE MORNING. TEMPERATURES WILL REMAIN COOL WEDNESDAY
AND THURSDAY WITH HIGHS MAINLY IN THE 50S. ON WEDNESDAY...
TEMPERATURES MAY GET NO HIGHER THAN THE MID TO UPR 40S ALONG THE
COAST INCLUDING THE NORFOLK AND VIRGINIA BEACH AREA AND THE LOWER
EASTERN SHORE. LOWS THURSDAY MORNING AGAIN ARE FORECAST TO FALL TO
AROUND 30 OVER INTERIOR PORTIONS. SOME FROST IS POSSIBLE AS WELL
INCLUDING LOCATIONS THAT ONLY FALL TO THE LOW TO MID 30S. ANY NEEDED
HEADLINES WILL BE DEFERRED TO LATER SHIFTS.
TEMPERATURES WARM A BIT FRIDAY WITH HIGHS IN THE LOWER 60S OVER
INTERIOR AREAS. THERE WILL BE A SLIGHT CHANCE FOR RAIN TOWARD THE
COAST...ESPECIALLY OVER SOUTHEAST VIRGINIA AND NORTHEAST NORTH
CAROLINA.
&&
.LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/...
AN AREA OF SFC LOW PRESSURE IS EXPECTED TO DEVELOP ON A STALLED
BOUNDARY OFF THE SOUTHEAST COAST FRI NIGHT. THE LOW SHOULD TRACK NE
WELL OFF THE CAROLINA COAST ON SAT. THIS FEATURE MAY BRING A FEW
RAIN SHOWERS TO FAR SE VA/NE NC DURING THIS TIMEFRAME.
MEANWHILE...AN UPPER LEVEL TROUGH OVER THE UPPER MIDWEST WILL SWING
INTO THE ERN GREAT LAKES FRI NIGHT AND SKIRT ACROSS NRN VA ON SAT. A
WEAK SFC LOW WILL BE ASSOCIATED WITH THIS FEATURE AND MAY BRING A
BRIEF ROUND OF SHOWERS TO FAR NRN PORTIONS OF THE FA (INCLUDING THE
MD/VA EASTERN SHORE) SAT AFTN/EARLY EVENING BEFORE MOVING OFFSHORE
AND DISSIPATING. THE SFC LOW ASSOCIATED WITH THE GREAT LAKES TROUGH
IS EXPECTED TO PHASE WITH THE AFOREMENTIONED COASTAL LOW SAT
NIGHT...BUT THIS SHOULD OCCUR OVER NEW ENGLAND AND HAVE VERY LITTLE
IMPACT TO THE MID ATLANTIC STATES. SFC HIGH PRESSURE BUILDS INTO THE
REGION SUN...THEN SLIDES OFFSHORE BY SUN EVENING AS A RELATIVELY
FLAT (WEST TO EAST ORIENTED) FRONTAL BOUNDARY SAGS DOWN INTO THE
AREA MON NIGHT INTO TUE. WEAK SHORTWAVE ENERGY AND A SUBSEQUENT SFC
LOW TRAVELLING ALONG THIS BOUNDARY MAY BRING ANOTHER SHOT OF
PRECIPITATION TO THE AREA ON MON/TUE. GFS PRECIP-GENERATION AND
GENERAL MOVEMENT IS A BIT AGGRESSIVE VERSUS THE ECMWF...THEREFORE
TRIED TO SPLIT THE DIFFERENCE WITH THE POP FORECAST AND LIMITED
COVERAGE TO NO HIGHER THAN 40 PERCENT.
TEMPERATURES ARE EXPECTED TO BE STRAIGHT-FORWARD SAT NIGHT THROUGH
SUN NIGHT AS HIGH PRESSURE CROSSES THE REGION. EXPECT LOWS NEAR
NORMAL BOTH NIGHTS IN THE 40S (LOWER 50S POSSIBLE IMMEDIATE SE VA/NE
NC COASTS). HIGHS SAT/SUN RANGE FROM ROUGHLY 65 DEGREES FAR NE TO 70
DEGREES SW. AS THE FLAT FRONTAL BOUNDARY STARTS TO SAG INTO THE MID
ATLANTIC STATES MON THROUGH TUE...THE TEMP FORECAST BECOMES TRICKY
IN REGARD TO WHERE EXACTLY THE WARM SECTOR DEVELOPS. WITH PRECIP
EXPECTED TO APPROACH THE AREA ON MON...INCREASING CIRRUS SHOULD KEEP
HIGH TEMPS IN THE UPPER 60S WEST OF I-95 WITH WARMER TEMPS IN THE
LOWER 70S EAST OF I-95 (MID-UPPER 60S MD/VA EASTERN SHORE). HIGHS
TUE SHOULD BE IN THE LOWER 70S INLAND AND IN THE UPPER 60S NEAR THE
IMMEDIATE CHES BAY AND ATLANTIC COASTS. LOW TEMPERATURES AREAWIDE ON
MON/TUE NIGHT SHOULD ALSO BE WARM WITH READINGS IN THE 50S (OR ABOUT
10 DEGREES ABOVE NORMAL).
&&
.AVIATION /20Z TUESDAY THROUGH SUNDAY/...
INITIAL BATCH OF SHOWERS AND TSTMS HAS MOVED OFF THE COAST THIS
MORNING. THE MAIN FRONT IS STILL WELL TO THE WEST. TIMING LOOKS
QUITE GOOD ON THE NAM AND RUC SO WILL FOLLOW THEM CLOSELY. NOTICED
MAINLY VFR TO MVFR CONDITIONS AHEAD OF THE FRONT AND WILL MAINTAIN
THAT. WITH THE UPPER SYSTEM NOW ROTATING NORTHEAST TOWARD THE AREA
CAN SEE MORE SHOWERS AHEAD AND BEHIND THE FRONT DEVELOPING. WILL
CONTINUE JUST SCATTERED SHOWERS AHEAD OF THE FRONT. THE RUC MODEL
SOUNDINGS AND THE LACK OF INSTABILITY INDICATE IT WILL BE HARD FOR
ANY TSTMS TO DEVELOP. SO FOR NOW WILL NOT PUT THEM IN THE TAFS BUT
IT IS STILL POSSIBLE FOR SOME TO FORM ALONG THE FRONT AS IT
CROSSES THE AREA. BEHIND THE FRONT MODELS SHOW AT LEAST SEVER
HOURS OF MODERATE TO HEAVY SHOWERS ESPECIALLY OVER SOUTHEAST
VIRGINIA AND NORTHEAST NORTH CAROLINA. WILL GIVE A TEMPO GROUP
THERE FOR LOWER CIGS AND VSBY WITH THESE SHOWERS. CURRENTLY WEST
OF THE FRONT ONLY MVFR CONDITIONS AND CURRENT GUIDANCE ALSO GOING
MVFR. WILL KEEP PREDOMINATE CIGS AND VSBY MVFR.
IT WILL BECOME WINDY ESPECIALLY AFTER THE FRONT PASSES WITH
NORTHWEST WINDS GUSTING OVER 30 KTS AND COULD BE OVER 35 KTS IN
ORF. THESE WINDS WILL SLOWLY DIMINISH LATER TONIGHT BUT REMAIN
NORTHWEST 15 TO 20 THROUGH THE MORNING ON WEDNESDAY.
SKIES CLEAR LATE TONIGHT AND CONTINUE VFR CONDITIONS THROUGH
THURSDAY AS HIGH PRESSURE BUILDS OVER THE AREA.
&&
.MARINE...
GALE WARNGS WILL CONTINUE AS PLANNED FOR ALL WTRS TDY INTO TNGT. A
STRONG COLD FRNT IS CURRENTLY APPROACHING THE MID ATLANTIC
CST...WITH GUSTY SLY FLOW AHEAD OF THE FRNT TO BE FOLLOWED BY
STRONGER NW FLOW BEHIND THE FRNT. EXPECT GUSTS UP TO 35-40 KT OVRNGT
AS THE FRNT PUSHES OFFSHORE AND HI PRES BLDS IN FROM THE W WITH
LARGE PRES RISES. WAVES WILL RISE TO 4 TO 6 FT OVR THE BAY...AND
SEAS WILL RISE TO 6 TO 9 FT ON THE CSTL WTRS. HI PRES CONTINUES TO
BLD IN THRU WED AFTN...WHICH WILL ALLOW THE GRADIENT TO WEAKEN
SIGNIFICANTLY. STILL HAVE THE GALES ENDING AT 7 AM FOR THE
BAY/RIVERS...AND HOLDING INTO THE ERLY AFTN FOR THE CST AND SOUND.
HI PRES SLIDES NE ACRS NEW ENGLAND AND INTO THE CANADIAN MARITIMES
WED NGT THRU FRI...AS A WEAK CSTL TROF DEVELOPS OFF THE SE CST. THIS
WILL RESULT IN A PROLONGED PERIOD OF NE WINDS AND ELEVATED SEAS THRU
THE END OF THE WEEK.
&&
.AKQ WATCHES/WARNINGS/ADVISORIES...
MD...FREEZE WARNING FROM 3 AM TO 9 AM EDT WEDNESDAY FOR MDZ021>024.
NC...FREEZE WARNING FROM 3 AM TO 9 AM EDT WEDNESDAY FOR NCZ012.
VA...FREEZE WARNING FROM 3 AM TO 9 AM EDT WEDNESDAY FOR VAZ048-049-
060>085-087>094.
MARINE...GALE WARNING UNTIL 10 AM EDT WEDNESDAY FOR ANZ650-652-654.
GALE WARNING UNTIL 1 PM EDT WEDNESDAY FOR ANZ633-656-658.
GALE WARNING UNTIL 7 AM EDT WEDNESDAY FOR ANZ630>632-634>638.
&&
$$
SYNOPSIS...LSA
NEAR TERM...LSA
SHORT TERM...LSA
LONG TERM...BMD
AVIATION...LKB/JAB
MARINE...MAS
AREA FORECAST DISCUSSION
NWS WAKEFIELD VA
308 PM EDT TUE APR 15 2014
.SYNOPSIS...
A STRONG COLD FRONT WILL CROSS THE AREA TODAY...THEN MOVE OFF THE
COAST THIS EVENING. CANADIAN HIGH PRESSURE BUILDS IN FROM THE
NORTHWEST TUESDAY NIGHT AND SETTLES OVER THE MID ATLANTIC AND
NORTHEAST WEDNESDAY AND THURSDAY.
&&
.NEAR TERM /UNTIL 6 AM WEDNESDAY MORNING/...
THE SEVERE THREAT FOR THIS AFTERNOON AND EVENING HAS DIMINISHED
FROM EARLIER FORECASTS. THE SPC SLIGHT RISK HAS BEEN REMOVED. THIS
DOES NOT ELIMINATE THE POSSIBILITY OF SEVERE THUNDERSTORMS.
SHOWERS AND THUNDERSTORMS ALONG THE COLD FRONT COULD STILL MIX
DOWN SOME WIND GUSTS THAT WOULD APPROACH OR EXCEED SEVERE CRITERIA.
THE SEVERE POTENTIAL HAS DIMINISHED FOR A FEW REASONS: THE LINE OF
SHOWERS AND THUNDERSTORMS THAT MOVED OFFSHORE AROUND NOON RESULTED
IN SOME STABILIZING. THUNDERSTORMS OVER GEORGIA IS ROBBING SOME OF
THE INFLUX OF MOISTURE TO THE AREA. FINALLY...THE BACKING OF
SURFACE WINDS TO SE IS NOT AS IMPRESSIVE AS EARLIER EXPECTED.
AT 1 PM EDT...THE COLD FRONT WAS NEAR THE SHENANDOAH VALLEY IN
NORTHERN VIRGINIA AND JUST EAST OF LYNCHBURG. A BAND OF HEAVY RAIN
AND GUSTY WINDS CAN BE EXPECTED WITH THE FRONTAL PASSAGE. MOST
WIND GUSTS SHOULD BE 40 MPH OR LESS BUT ISOLATED SEVERE GUSTS ARE
STILL POSSIBLE.
HIGH TEMPERATURES TODAY WILL GENERALLY RUN BETWEEN 70 AND 75.
TEMPERATURES WILL FALL NOTICEABLY FOLLOWING THE COLD FRONT WITH
READINGS IN THE 50S IN THE PIEDMONT COUNTIES AND INTERIOR NORTHERN
NECK BY LATE AFTERNOON.
STRONG NORTH WINDS ARE FORECAST ALONG THE COAST. WINDS OF 25 TO 35
MPH WITH HIGHER GUSTS ARE EXPECTED THIS EVENING OVER PORTIONS OF
HAMPTON ROADS AND CURRITUCK COUNTY NORTH CAROLINA THIS EVENING.
THESE WINDS ARE ALSO EXPECTED IN THE VIRGINIA PORTION OF THE LOWER
EASTERN SHORE. STRONGEST WINDS WILL BE NEAR THE COAST AND IN AREAS
OF HAMPTON ROADS DIRECTLY EXPOSED TO THE CHESAPEAKE BAY.
RAIN MOVES OFF THE COAST LATE THIS EVENING. SKIES WILL CLEAR
OVERNIGHT FROM WEST TO EAST. .
LOW TEMPERATURES TONIGHT DROP TO BETWEEN 28 AND 32 OVER INLAND
RURAL AREAS. A FREEZE WARNING IS IN EFFECT FOR MOST OF EASTERN
VIRGINIA EXCLUDING SOUTHSIDE HAMPTON ROADS AND THE LOWER VIRGINIA
EASTERN SHORE. THE FREEZE WARNING IS IN EFFECT FOR THE MD EASTERN
SHORE EXCEPT FOR OCEAN CITY.
&&
.SHORT TERM /6 AM WEDNESDAY MORNING THROUGH THURSDAY/...
COLD WEDNESDAY UNDER SUNNY SKIES. LIKELY WILL BE SOME STREAMERS
OVER THE BAY INTO SE VA/NE NC WEDS MORNING. H85 TEMPS WILL FALL TO
~-5C (-2 STD DEV)...TRANSLATING TO DAYTIME TEMPS GENERALLY IN THE
LOW 50S...EVEN UNDER THE STRONG APRIL SUN. TEMPS AGAIN MAY FALL TO
AROUND FREEZING OVER INLAND COUNTIES WED NIGHT-THURS MORNING.
THERE IS A POSSIBILITY FOR LIGHT RAIN NEAR THE NC COAST BY THURS.
&&
.LONG TERM /THURSDAY NIGHT THROUGH TUESDAY/...
AN AREA OF SFC LOW PRESSURE IS EXPECTED TO DEVELOP ON A STALLED
BOUNDARY OFF THE SOUTHEAST COAST FRI NIGHT. THE LOW SHOULD TRACK NE
WELL OFF THE CAROLINA COAST ON SAT. THIS FEATURE MAY BRING A FEW
RAIN SHOWERS TO FAR SE VA/NE NC DURING THIS TIMEFRAME.
MEANWHILE...AN UPPER LEVEL TROUGH OVER THE UPPER MIDWEST WILL SWING
INTO THE ERN GREAT LAKES FRI NIGHT AND SKIRT ACROSS NRN VA ON SAT. A
WEAK SFC LOW WILL BE ASSOCIATED WITH THIS FEATURE AND MAY BRING A
BRIEF ROUND OF SHOWERS TO FAR NRN PORTIONS OF THE FA (INCLUDING THE
MD/VA EASTERN SHORE) SAT AFTN/EARLY EVENING BEFORE MOVING OFFSHORE
AND DISSIPATING. THE SFC LOW ASSOCIATED WITH THE GREAT LAKES TROUGH
IS EXPECTED TO PHASE WITH THE AFOREMENTIONED COASTAL LOW SAT
NIGHT...BUT THIS SHOULD OCCUR OVER NEW ENGLAND AND HAVE VERY LITTLE
IMPACT TO THE MID ATLANTIC STATES. SFC HIGH PRESSURE BUILDS INTO THE
REGION SUN...THEN SLIDES OFFSHORE BY SUN EVENING AS A RELATIVELY
FLAT (WEST TO EAST ORIENTED) FRONTAL BOUNDARY SAGS DOWN INTO THE
AREA MON NIGHT INTO TUE. WEAK SHORTWAVE ENERGY AND A SUBSEQUENT SFC
LOW TRAVELLING ALONG THIS BOUNDARY MAY BRING ANOTHER SHOT OF
PRECIPITATION TO THE AREA ON MON/TUE. GFS PRECIP-GENERATION AND
GENERAL MOVEMENT IS A BIT AGGRESSIVE VERSUS THE ECMWF...THEREFORE
TRIED TO SPLIT THE DIFFERENCE WITH THE POP FORECAST AND LIMITED
COVERAGE TO NO HIGHER THAN 40 PERCENT.
TEMPERATURES ARE EXPECTED TO BE STRAIGHT-FORWARD SAT NIGHT THROUGH
SUN NIGHT AS HIGH PRESSURE CROSSES THE REGION. EXPECT LOWS NEAR
NORMAL BOTH NIGHTS IN THE 40S (LOWER 50S POSSIBLE IMMEDIATE SE VA/NE
NC COASTS). HIGHS SAT/SUN RANGE FROM ROUGHLY 65 DEGREES FAR NE TO 70
DEGREES SW. AS THE FLAT FRONTAL BOUNDARY STARTS TO SAG INTO THE MID
ATLANTIC STATES MON THROUGH TUE...THE TEMP FORECAST BECOMES TRICKY
IN REGARD TO WHERE EXACTLY THE WARM SECTOR DEVELOPS. WITH PRECIP
EXPECTED TO APPROACH THE AREA ON MON...INCREASING CIRRUS SHOULD KEEP
HIGH TEMPS IN THE UPPER 60S WEST OF I-95 WITH WARMER TEMPS IN THE
LOWER 70S EAST OF I-95 (MID-UPPER 60S MD/VA EASTERN SHORE). HIGHS
TUE SHOULD BE IN THE LOWER 70S INLAND AND IN THE UPPER 60S NEAR THE
IMMEDIATE CHES BAY AND ATLANTIC COASTS. LOW TEMPERATURES AREAWIDE ON
MON/TUE NIGHT SHOULD ALSO BE WARM WITH READINGS IN THE 50S (OR ABOUT
10 DEGREES ABOVE NORMAL).
&&
.AVIATION /19Z TUESDAY THROUGH SUNDAY/...
INITIAL BATCH OF SHOWERS AND TSTMS HAS MOVED OFF THE COAST THIS
MORNING. THE MAIN FRONT IS STILL WELL TO THE WEST. TIMING LOOKS
QUITE GOOD ON THE NAM AND RUC SO WILL FOLLOW THEM CLOSELY. NOTICED
MAINLY VFR TO MVFR CONDITIONS AHEAD OF THE FRONT AND WILL MAINTAIN
THAT. WITH THE UPPER SYSTEM NOW ROTATING NORTHEAST TOWARD THE AREA
CAN SEE MORE SHOWERS AHEAD AND BEHIND THE FRONT DEVELOPING. WILL
CONTINUE JUST SCATTERED SHOWERS AHEAD OF THE FRONT. THE RUC MODEL
SOUNDINGS AND THE LACK OF INSTABILITY INDICATE IT WILL BE HARD FOR
ANY TSTMS TO DEVELOP. SO FOR NOW WILL NOT PUT THEM IN THE TAFS BUT
IT IS STILL POSSIBLE FOR SOME TO FORM ALONG THE FRONT AS IT
CROSSES THE AREA. BEHIND THE FRONT MODELS SHOW AT LEAST SEVER
HOURS OF MODERATE TO HEAVY SHOWERS ESPECIALLY OVER SOUTHEAST
VIRGINIA AND NORTHEAST NORTH CAROLINA. WILL GIVE A TEMPO GROUP
THERE FOR LOWER CIGS AND VSBY WITH THESE SHOWERS. CURRENTLY WEST
OF THE FRONT ONLY MVFR CONDITIONS AND CURRENT GUIDANCE ALSO GOING
MVFR. WILL KEEP PREDOMINATE CIGS AND VSBY MVFR.
IT WILL BECOME WINDY ESPECIALLY AFTER THE FRONT PASSES WITH
NORTHWEST WINDS GUSTING OVER 30 KTS AND COULD BE OVER 35 KTS IN
ORF. THESE WINDS WILL SLOWLY DIMINISH LATER TONIGHT BUT REMAIN
NORTHWEST 15 TO 20 THROUGH THE MORNING ON WEDNESDAY.
SKIES CLEAR LATE TONIGHT AND CONTINUE VFR CONDITIONS THROUGH
THURSDAY AS HIGH PRESSURE BUILDS OVER THE AREA.
&&
.MARINE...
RAISED GALE WARNINGS FOR ALL MARINE ZONES...REMOVED RAMP-UP SCA`S AS
WE ARE WITHIN ~ 12 HRS OF THE ONSET OF GALE CONDITIONS.
SOUTHERLY FLOW TODAY WILL INCREASE TO AROUND 20-25 KT WITH GUSTS TO
30 KT...AS PRESSURE FALLS MOVE INTO THE AREA AHEAD OF THE
APPROACHING COLD FRONT. HOWEVER...STRONGER WINDS ARE ANTICIPATED
BETWEEN ABOUT 20Z AND 00Z AS WINDS SHIFT IN ASSOCIATION WITH THE
FRONT (AND MAY BE ENHANCED BY SCATTERED CONVECTION). THIS
EVENING...IMPRESSIVE PRESSURE RISES ON THE ORDER OF 12 TO 15 MB IN A
6 HR PERIOD SHOULD BRING GUSTS OF 35-40 KT FOR ALL ZONES. THIS WILL
ALSO USHER IN MUCH COLDER AIR THAT WILL ENHANCE MIXING OVER THE
WATERS. WAVES WILL BLD TO 4 TO 6 FT OVR THE CHES BAY...AND SEAS WILL
BLD TO 5 TO 9 FT ON THE COASTAL WATERS. HI PRES WILL THEN BLD JUST
TO THE N BY WED AFTN...WHICH WILL ALLOW THE GRADIENT TO WEAKEN
SIGNIFICANTLY. HAVE THE GALES ENDING AT 12Z FOR THE BAY/RIVERS...BUT
HOLDING INTO EARLY AFTN FOR THE COAST AND CURRITUCK SOUND. HIGH
PRESSURE SLIDES NE ACRS NEW ENGLAND AND INTO THE CANADIAN MARITIMES
WED NGT THRU FRI...AS A WEAK COASTAL TROUGH DEVELOPS OFF THE SE
COAST. THIS WILL RESULT IN NE WINDS AND ELEVATED SEAS THRU THE END
OF THE WEEK.
&&
.AKQ WATCHES/WARNINGS/ADVISORIES...
MD...FREEZE WARNING FROM 3 AM TO 9 AM EDT WEDNESDAY FOR MDZ021>024.
NC...FREEZE WARNING FROM 3 AM TO 9 AM EDT WEDNESDAY FOR NCZ012.
VA...FREEZE WARNING FROM 3 AM TO 9 AM EDT WEDNESDAY FOR VAZ048-049-
060>085-087>094.
MARINE...GALE WARNING UNTIL 10 AM EDT WEDNESDAY FOR ANZ650-652-654.
GALE WARNING UNTIL 1 PM EDT WEDNESDAY FOR ANZ633-656-658.
GALE WARNING UNTIL 7 AM EDT WEDNESDAY FOR ANZ630>632-634>638.
&&
$$
SYNOPSIS...LSA
NEAR TERM...LSA
SHORT TERM...SAM
LONG TERM...BMD
AVIATION...LKB/JAB
MARINE...LKB
AREA FORECAST DISCUSSION
NWS WAKEFIELD VA
145 PM EDT TUE APR 15 2014
.SYNOPSIS...
A STRONG COLD FRONT WILL CROSS THE AREA TODAY...THEN MOVE OFF THE
COAST THIS EVENING. CANADIAN HIGH PRESSURE BUILDS IN FROM THE
NORTHWEST TUESDAY NIGHT AND SETTLES OVER THE MID ATLANTIC AND
NORTHEAST WEDNESDAY AND THURSDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
THE SEVERE THREAT FOR THIS AFTERNOON AND EVENING HAS DIMINISHED
FROM EARLIER FORECASTS. THE SPC SLIGHT RISK HAS BEEN REMOVED. THIS
DOES NOT ELIMINATE THE POSSIBILITY OF SEVERE THUNDERSTORMS.
SHOWERS AND THUNDERSTORMS ALONG THE COLD FRONT COULD STILL MIX
DOWN SOME WIND GUSTS THAT WOULD APPROACH OR EXCEED SEVERE CRITERIA.
THE SEVERE POTENTIAL HAS DIMINISHED FOR A FEW REASONS: THE LINE OF
SHOWERS AND THUNDERSTORMS THAT MOVED OFFSHORE AROUND NOON RESULTED
IN SOME STABILIZING. THUNDERSTORMS OVER GEORGIA IS ROBBING SOME OF
THE INFLUX OF MOISTURE TO THE AREA. FINALLY...THE BACKING OF
SURFACE WINDS TO SE IS NOT AS IMPRESSIVE AS EARLIER EXPECTED.
AT 1 PM EDT...THE COLD FRONT WAS NEAR THE SHENANDOAH VALLEY IN
NORTHERN VIRGINIA AND JUST EAST OF LYNCHBURG. A BAND OF HEAVY RAIN
AND GUSTY WINDS CAN BE EXPECTED WITH THE FRONTAL PASSAGE. MOST
WIND GUSTS SHOULD BE 40 MPH OR LESS BUT ISOLATED SEVERE GUSTS ARE
STILL POSSIBLE.
HIGH TEMPERATURES TODAY WILL GENERALLY RUN BETWEEN 70 AND 75.
TEMPERATURES WILL FALL NOTICEABLY FOLLOWING THE COLD FRONT WITH
READINGS IN THE 50S IN THE PIEDMONT COUNTIES AND INTERIOR NORTHERN
NECK BY LATE AFTERNOON.
STRONG NORTH WINDS ARE FORECAST ALONG THE COAST. WINDS OF 25 TO 35
MPH WITH HIGHER GUSTS ARE EXPECTED THIS EVENING OVER PORTIONS OF
HAMPTON ROADS AND CURRITUCK COUNTY NORTH CAROLINA THIS EVENING.
THESE WINDS ARE ALSO EXPECTED IN THE VIRGINIA PORTION OF THE LOWER
EASTERN SHORE. STRONGEST WINDS WILL BE NEAR THE COAST AND IN AREAS
OF HAMPTON ROADS DIRECTLY EXPOSED TO THE CHESAPEAKE BAY.
RAIN MOVES OFF THE COAST LATE THIS EVENING. SKIES WILL CLEAR
OVERNIGHT FROM WEST TO EAST. .
LOW TEMPERATURES TONIGHT DROP TO BETWEEN 28 AND 32 OVER INLAND
RURAL AREAS. A FREEZE WARNING IS IN EFFECT FOR MOST OF EASTERN
VIRGINIA EXCLUDING SOUTHSIDE HAMPTON ROADS AND THE LOWER VIRGINIA
EASTERN SHORE. THE FREEZE WARNING IS IN EFFECT FOR THE MD EASTERN
SHORE EXCEPT FOR OCEAN CITY.
&&
.SHORT TERM /WEDNESDAY THROUGH THURSDAY/...
COLD WEDNESDAY UNDER SUNNY SKIES. LIKELY WILL BE SOME STREAMERS
OVER THE BAY INTO SE VA/NE NC WEDS MORNING. H85 TEMPS WILL FALL TO
~-5C (-2 STD DEV)...TRANSLATING TO DAYTIME TEMPS GENERALLY IN THE
LOW 50S...EVEN UNDER THE STRONG APRIL SUN. TEMPS AGAIN MAY FALL TO
AROUND FREEZING OVER INLAND COUNTIES WED NIGHT-THURS MORNING.
THERE IS A POSSIBILITY FOR LIGHT RAIN NEAR THE NC COAST BY THURS.
&&
.LONG TERM /THURSDAY NIGHT THROUGH TUESDAY/...
STRONG SFC HIGH PRESSURE REMAINS ANCHORED OVER NEW ENGLAND TO
BEGIN THE MEDIUM RANGE FORECAST PERIOD, RESULTING IN CONTINUED NE
FLOW OVER THE MID ATLANTIC FRIDAY. TEMPERATURES WILL BE COOL TO
BEGIN THE PERIOD FRIDAY...ABOUT ONE STANDARD DEVIATION BELOW
NORMAL...WITH TEMPS MODERATING A BIT SATURDAY. ALOFT, NORTHERN
STREAM SHORTWAVE TROUGH, AND ATTENDANT SFC LOW IS EXPECTED TO PUSH
ACROSS THE MID MS VLY TOWARDS THE EASTERN GREAT LAKES FRI-SAT,
EVENTUALLY PUSHING A MAINLY DRY COLD FRONT THROUGH SAT NGT AND
EARLY SUNDAY. BOTH MODELS DO TAKE A PIECE OF SHORTWAVE ENERGY
ACROSS THE MID-SOUTH TOWARDS THE CAROLINA COAST FRIDAY-SATURDAY,
WITH RESULTANT WEAK INVERTED TROUGHING THAT DEVELOPS PROMPTING
SOME LOW POPS LATER FRIDAY AND SATURDAY. THE 12Z/14 EURO SOLUTION
REMAINS A BIT WETTER THAN THE PROGRESSIVE GFS SOLUTION. HAVE SPLIT
THE DIFFERENCE BETWEEN THE GFS/UKMET FOR THIS PACKAGE. RIGHT NOW,
IT APPEARS THAT THE BEST RAIN CHC WOULD BE OVER EASTERN SECTIONS
ALONG THE COASTAL TROUGH FRIDAY NIGHT THROUGH MIDDAY SATURDAY.
UPPER TROUGH EJECTS NORTHEAST LATER SATURDAY, WITH SHORTWAVE
RIDGING ARRIVING FROM THE WEST SHUNTING SYSTEM OFFSHORE. QUICK
CLEARING EXPECTED THEREAFTER TOWARDS THE TAIL END OF THE PERIOD
(EASTER SUNDAY AND MONDAY).
&&
.AVIATION /18Z TUESDAY THROUGH SUNDAY/...
INITIAL BATCH OF SHOWERS AND TSTMS HAS MOVED OFF THE COAST THIS
MORNING. THE MAIN FRONT IS STILL WELL TO THE WEST. TIMING LOOKS
QUITE GOOD ON THE NAM AND RUC SO WILL FOLLOW THEM CLOSELY. NOTICED
MAINLY VFR TO MVFR CONDITIONS AHEAD OF THE FRONT AND WILL MAINTAIN
THAT. WITH THE UPPER SYSTEM NOW ROTATING NORTHEAST TOWARD THE AREA
CAN SEE MORE SHOWERS AHEAD AND BEHIND THE FRONT DEVELOPING. WILL
CONTINUE JUST SCATTERED SHOWERS AHEAD OF THE FRONT. THE RUC MODEL
SOUNDINGS AND THE LACK OF INSTABILITY INDICATE IT WILL BE HARD FOR
ANY TSTMS TO DEVELOP. SO FOR NOW WILL NOT PUT THEM IN THE TAFS BUT
IT IS STILL POSSIBLE FOR SOME TO FORM ALONG THE FRONT AS IT
CROSSES THE AREA. BEHIND THE FRONT MODELS SHOW AT LEAST SEVER
HOURS OF MODERATE TO HEAVY SHOWERS ESPECIALLY OVER SOUTHEAST
VIRGINIA AND NORTHEAST NORTH CAROLINA. WILL GIVE A TEMPO GROUP
THERE FOR LOWER CIGS AND VSBY WITH THESE SHOWERS. CURRENTLY WEST
OF THE FRONT ONLY MVFR CONDITIONS AND CURRENT GUIDANCE ALSO GOING
MVFR. WILL KEEP PREDOMINATE CIGS AND VSBY MVFR.
IT WILL BECOME WINDY ESPECIALLY AFTER THE FRONT PASSES WITH
NORTHWEST WINDS GUSTING OVER 30 KTS AND COULD BE OVER 35 KTS IN
ORF. THESE WINDS WILL SLOWLY DIMINISH LATER TONIGHT BUT REMAIN
NORTHWEST 15 TO 20 THROUGH THE MORNING ON WEDNESDAY.
SKIES CLEAR LATE TONIGHT AND CONTINUE VFR CONDITIONS THROUGH
THURSDAY AS HIGH PRESSURE BUILDS OVER THE AREA.
&&
.MARINE...
RAISED GALE WARNINGS FOR ALL MARINE ZONES...REMOVED RAMP-UP SCA`S AS
WE ARE WITHIN ~ 12 HRS OF THE ONSET OF GALE CONDITIONS.
SOUTHERLY FLOW TODAY WILL INCREASE TO AROUND 20-25 KT WITH GUSTS TO
30 KT...AS PRESSURE FALLS MOVE INTO THE AREA AHEAD OF THE
APPROACHING COLD FRONT. HOWEVER...STRONGER WINDS ARE ANTICIPATED
BETWEEN ABOUT 20Z AND 00Z AS WINDS SHIFT IN ASSOCIATION WITH THE
FRONT (AND MAY BE ENHANCED BY SCATTERED CONVECTION). THIS
EVENING...IMPRESSIVE PRESSURE RISES ON THE ORDER OF 12 TO 15 MB IN A
6 HR PERIOD SHOULD BRING GUSTS OF 35-40 KT FOR ALL ZONES. THIS WILL
ALSO USHER IN MUCH COLDER AIR THAT WILL ENHANCE MIXING OVER THE
WATERS. WAVES WILL BLD TO 4 TO 6 FT OVR THE CHES BAY...AND SEAS WILL
BLD TO 5 TO 9 FT ON THE COASTAL WATERS. HI PRES WILL THEN BLD JUST
TO THE N BY WED AFTN...WHICH WILL ALLOW THE GRADIENT TO WEAKEN
SIGNIFICANTLY. HAVE THE GALES ENDING AT 12Z FOR THE BAY/RIVERS...BUT
HOLDING INTO EARLY AFTN FOR THE COAST AND CURRITUCK SOUND. HIGH
PRESSURE SLIDES NE ACRS NEW ENGLAND AND INTO THE CANADIAN MARITIMES
WED NGT THRU FRI...AS A WEAK COASTAL TROUGH DEVELOPS OFF THE SE
COAST. THIS WILL RESULT IN NE WINDS AND ELEVATED SEAS THRU THE END
OF THE WEEK.
&&
.AKQ WATCHES/WARNINGS/ADVISORIES...
MD...FREEZE WARNING FROM 3 AM TO 9 AM EDT WEDNESDAY FOR MDZ021>024.
NC...FREEZE WARNING FROM 3 AM TO 9 AM EDT WEDNESDAY FOR NCZ012.
VA...FREEZE WARNING FROM 3 AM TO 9 AM EDT WEDNESDAY FOR VAZ048-049-
060>085-087>094.
MARINE...GALE WARNING UNTIL 10 AM EDT WEDNESDAY FOR ANZ650-652-654.
GALE WARNING UNTIL 1 PM EDT WEDNESDAY FOR ANZ633-656-658.
GALE WARNING UNTIL 7 AM EDT WEDNESDAY FOR ANZ630>632-634>638.
&&
$$
SYNOPSIS...LSA
NEAR TERM...LSA
SHORT TERM...SAM
LONG TERM...MAM/JEF
AVIATION...LKB/JAB
MARINE...LKB
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
531 PM EDT TUE APR 15 2014
.SHORT TERM...(THIS EVENING THROUGH WEDNESDAY)
ISSUED AT 531 PM EDT TUE APR 15 2014
BIGGEST FORECAST CONCERNS FOR SHORT TERM FOCUS ON WINTER STORM
HEADLINES STARTING WEDNESDAY AND CONTINUING INTO THURSDAY.
WV IMAGERY AND RUC ANALYSIS INDICATED A MID/UPPER LEVEL TROUGH FROM
HUDSON BAY THROUGH THE CENTRAL GREAT LAKES INTO THE GULF COAST
STATES. INSTABILITY ASSOC WITH THIS TROUGH HAS SUPPORTED SOME
DIURNAL -SHSN ACROSS INLAND AREAS THIS AFTERNOON. THE SHORTWAVE
MOVING IN OFF THE PAC NW WILL BE THE FEATURE OF INTEREST IN THE
SHORT TERM AS IT DEVELOPS A DEEPENING STORM SYSTEM OVER THE NRN
PLAINS LATE TONIGHT AND BRINGS IT TOWARD THE WRN GREAT LAKES LATE
WED INTO WED NIGHT.
TONIGHT...ANY LEFTOVER DIURNAL SHSN OVER S CNTRL UPPER MI WILL
DIMINISH EARLY THIS EVENING AS PARTLY CLOUDY SKIES AND LIGHT WINDS
ALLOW TEMPS TO FALL INTO THE LOW SINGLE DIGITS OVER TYPICAL COLD
SPOTS FAR EAST TO 15 TO 20F RANGE FOR DOWNSLOPING AREAS ALONG LAKE
SUPERIOR FAR WEST AND AREAS CLOSE TO BAY OF GREEN BAY. TEMPS MAY
CLIMB LATE AS CLOUDS INCREASE AHEAD OF THE APPROACHING LOW PRESSURE
SYSTEM. WAA LIGHT SNOW WITH INCREASING 280K-290K ISENTROPIC LIFT IS
EXPECTED TO REMAIN MAINLY WEST OF UPPER MI BUT MAY SLIDE INTO THE
FAR WEST LATE.
WEDNESDAY...MODELS GENERALLY IN AGREEMENT SHOWING SHORTWAVE OF
INTEREST AND ASSOC DEEPENING SFC LOW OVER SE SOUTH DAKOTA AROUND 12Z
THEN DIFFER ON HOW QUICKLY THEY LIFT THIS LOW ENE TOWARD THE UPPER
GREAT LAKES. MOST OF 12Z MODELS GENERALLY TRENDING SLIGHTLY SLOWER
AND FARTHER SE THAN 06Z RUNS WITH TRACK OF SFC LOW. MODELS INDICATE
WARM AIR ADVECTION AND ISENTROPIC ASCENT ALONG AND AHEAD OF THE LOW
AND INVERTED SFC TROUGH SHOULD SUPPORT EXPANDING SNOW SHIELD FM
CNTRL MINNESOTA INTO NORTHWEST WI LATE TONIGHT THROUGH DAYBREAK ON
WEDNESDAY. THIS SNOW SHIELD WILL THEN SPREAD INTO WEST AND CENTRAL
UPPER MI DURING THE DAY ON WEDNESDAY. AS SFC TROUGH EDGES CLOSER TO
UPR MICHIGAN WED AFTN ISENTROPIC ASCENT BECOMES MAXIMIZED ON
285-290K SFCS ACROSS UPR MICHIGAN FROM 15Z INTO WED EVENING. GFS
REMAINS QUICKEST OF 12Z MODELS WHILE THE ECMWF IS THE SLOWEST. THE
NAM AND REGIONAL GEM FALL SOMEWHERE BTWN THESE SOLNS. H7 MIXING
RATIOS IN 2.5-3 G/KG RANGE SUGGESTS 12 HOUR SNOW AMOUNTS 4-6 INCHES
OVER MAINLY THE WEST HALF COUNTIES. IT/S POSSIBLE ACTUAL SNOW
AMOUNTS ON WED COULD BE HELD DOWN SOME AS SNOW ARRIVES DURING THE
DAYTIME WHEN INSOLATION COULD LIMIT ACCUMS ESPECIALLY ON HIGHER
TRAFFIC/TRAVELLED ROADS. CROSS SECTIONS SUGGEST POSSIBILITY OF
HEAVIER BANDED SNOWFALL OVER WESTERN COUNTIES WITH NEG EPV ABOVE
FAIRLY STRONG 7H FGEN FORCING SO THIS COULD ADD A FEW INCHES TO THE
4-6 INCH TOTALS RENDERED SOLELY FM ISENTROPIC ASCENT.
WITH ALL ABOVE FACTORS TAKEN INTO CONSIDERATION...HAVE DECIDED TO
UPGRADE WATCHES OVER THE WEST HALF COUNTIES TO WARNINGS FROM
MQT-DICKINSON WESTWARD. GENERALLY STARTED WARNINGS ON WED FM 14Z
SOUTH TO 16Z NORTH. ALSO MOVED THE AXIS OF HEAVIER PCPN/SNOWFALL
SLIGHTLY FARTHER EASTWARD BASED ON 12Z MODEL TRENDS WITH SNOWFALL
AMOUNTS ON WED RANGING FM 3 TO 5 INCHES OVER THE NW CWA TO 4-7
INCHES OVER THE FAR SW CWA ALONG THE WI BDR. WENT WITH ADVISORIES
FOR MNM...DELTA AND ALGER COUNTIES WHERE 2-4 INCH AMOUNTS WILL BE
MORE COMMON ON WED WITH MUCH OF THE SNOW FALLING IN THE AFTERNOON
HRS. FARTHER EAST OVER SCHOOLCRAFT AND LUCE COUNTIES...LOW-LVL DRY
AIRMASS INITIALLY IN PLACE FROM LINGERING SFC RDG AXIS WILL TAKE A
BIT LONGER TO MOISTEN FM ISENTROPIC ASCENT SO ONLY EXPECT GENERALLY
1-2 INCHES OF SNOW THERE AND WILL HOLD OFF ON ANY HEADLINE THERE FOR
NOW. IF TONIGHT/S MODEL RUNS CONTINUE TO TREND EASTWARD MAY NEED TO
CONSIDER POSSIBILITY OF ADDING MNM AND POSSIBLY DELTA INTO
WARNING.
.LONG TERM...(WEDNESDAY NIGHT THROUGH TUESDAY)
ISSUED AT 531 PM EDT TUE APR 15 2014
LONG TERM PORTION OF THE FCST WILL BEGIN COLD/WINTRY AS SHORTWAVE
TAKES ADVANTAGE OF LINGERING TIGHT THERMAL GRADIENT OVER THE AREA
BTWN DEPARTING UNUSUALLY COLD AIR MASS FOR MID APR AND WARMTH
SPREADING OUT ACROSS THE CNTRL/SRN PLAINS. TEMPS WILL THEN SLOWLY
MODERATE AS DEEP TROF AND ASSOCIATED LATE SEASON ARCTIC AIR LIFT TO
GREENLAND...AND PACIFIC AIR MAKES INCREASING INROADS ACROSS THE
CONUS AND SRN CANADA. HEADING DOWN THE ROAD...IT LOOKS LIKE TEMPS
NEXT WEEK WILL GENERALLY FLUCTUATE AROUND NORMAL...BUT NOT
SIGNIFICANTLY ABOVE OR BLO NORMAL DURING THE TEMP SWINGS. THERE ARE
SOME INDICATIONS FROM GEM ENSEMBLES AND GFS RUNS THAT THE PATTERN
MAY BE FAIRLY ACTIVE OVER THE NEXT COUPLE OF WEEKS WHICH WILL MEAN
RAINFALL FOR MOST IF NOT ALL PCPN EVENTS. HOPEFULLY...SIGNIFICANT
RAINFALL WILL BE AVOIDED AS THE SNOWMELT SEASON RESUMES.
BEGINNING WED NIGHT...A HVY/WET SNOW EVENT WILL BE UNDERWAY AS
SHORTWAVE APPROACHES FROM THE UPPER MISSISSIPPI VALLEY. WITH 12Z
MODEL RUNS...MODELS THAT HAD MAX QPF AXIS ON THE NW SIDE OF THE
MODEL SPREAD HAVE SHIFTED SLIGHTLY S AND E. RESULT IS IMPROVING
MODEL AGREEMENT NOW ON WHERE AXIS OF HEAVIEST PCPN WILL SET UP. IT
APPEARS MAX QPF AXIS SHOULD RUN ROUGHLY FROM JUST N OF THE TWIN
CITIES TO THE HURON MTNS. THE NAM IS DISPLACED A LITTLE TO THE NW OF
THIS AXIS WHILE THE GEM REGIONAL/HEMISPHERIC ARE DISPLACED A LITTLE
TO THE SE. ALTHOUGH SFC LOW ASSOCIATED WITH SHORTWAVE WILL BE
WEAKENING AS IT TRACKS FROM THE NRN/CNTRL PLAINS TO THE UPPER
LAKES...BEST COMBINATION OF FORCING/MOISTURE WILL COME TOGETHER FROM
ERN MN E AND NE NTO UPPER MI BEFORE SYSTEM BEGINS TO FALL APART. AT
THE UPPER LEVELS...RIGHT ENTRANCE OF UPPER JET STREAK RUNNING FROM
NRN LAKE SUPERIOR/NRN ONTARIO EASTWARD WILL PROVIDE HEALTHY UPPER
DIVERGENCE. THERE ARE EVEN SOME HINTS OF BRIEF UPPER JET COUPLING
WITH LEFT EXIT OF JET SHIFTING ACROSS THE UPPER MIDWEST THAT IS
SUPPORTING THE SHORTWAVE. AT THE LOWER LEVELS...STRONG ISENTROPIC
ASCENT IS NOTED WITH MIXING RATIOS OF 3 TO 4G/KG AVBL AROUND
700-750MB. IN ADDITION...THERE IS STRONG FRONTOGENESIS WITH NEGATIVE
EPV/CONVECTIVE INSTABILITY NOTED OVERTOP THE FGEN. FINALLY...STEEP
MIDLEVEL LAPSE RATES ARE NOTED ADVECTING INTO THE SRN SIDE OF THE
PCPN AREA. ALL THIS POINTS TO THE LIKELIHOOD FOR HEAVIER BANDING OF
SNOW WITHIN THE OVERALL MDT/HVY PCPN AREA OR EVEN CONVECTIVE SNOW AT
TIMES...CERTAINLY NOT ATYPICAL FOR SPRINGTIME HVY SNOW EVENTS.
ULTIMATE PLACEMENT OF HEAVIEST SNOW WILL HINGE ON WHERE THESE
HEAVIER SNOWBANDS OR CONVECTIVE ELEMENTS SET UP. AS IT STANDS
NOW...LOCATIONS W OF KIMT/KMQT LINE SHOULD HAVE NO PROBLEM REACHING
WARNING CRITERIA WITH STORM TOTAL AMOUNTS AROUND 1 FOOT...PROBABLY
IN MANY LOCATIONS. ADVY ISSUED FOR NEXT TIER OF COUNTIES E MAY IN
FACT NEED TO BE UPGRADED TO WARNINGS GIVEN MODEL TRENDS. FINALLY...
EVEN THE FAR E COUNTIES OF SCHOOLCRAFT AND LUCE MAY NEED TO BE ADDED
TO AN ADVY IF THE E TREND HOLDS UP IN NEXT SET OF MODEL RUNS.
PCPN WINDS DOWN QUICKLY THU AND WILL LIKELY END. SFC HIGH PRES THEN
BUILDS INTO THE UPPER LAKES THU NIGHT THRU FRI NIGHT TO PROVIDE A
PERIOD OF QUIET WEATHER. NAM IN PARTICULAR SUGGESTS LOW CLOUDS MAY
LINGER THU NIGHT...AND THAT MAY BE THE CASE WITH SHALLOW COLD AIR
MASS OVER EXPANDING OPEN WATER ON LAKE SUPERIOR. IF CLOUDS DO CLEAR
OUT IN SOME AREAS THU NIGHT...EXPECT BKN DIURNAL CU DEVELOPMENT FRI
UNDER MID LEVEL TROF AND ASSOCIATED THERMAL TROF. NOT OUT OF THE
QUESTION THAT A FEW FLURRIES COULD EVEN DEVELOP. FRI HIGHS WILL BE
IN THE 30S N WITH A CHILLY WIND OFF THE ICE TO THE 40S S. WITH
CLOUDS CLEARING OUT FRI NIGHT...IT WILL BE A COLD NIGHT WITH HIGH
PRES STILL OVER THE AREA. FAVORED THE LOWER SIDE OF GUIDANCE WITH
SOME TEENS OVER THE W WHERE WINDS WILL BE LIGHTEST. COULD BE
CONSIDERABLY COLDER ACROSS ALL OF THE INTERIOR IF SKIES CLEAR EARLY
AND STAY THAT WAY FOR A GOOD PART OF THE NIGHT.
MODELS THEN DIVERGE WITH PROGRESSION OF NEXT SHORTWAVE FEATURE
MOVING OFF THE PACIFIC IN LOWER AMPLITUDE FLOW...THOUGH AGREEMENT IS
IMPROVING WITH TODAYS 12Z MODEL RUNS. GEM IS STRONGER WITH WAVE AND
IS HEAVIER WITH THE QPF THAN THE GFS/ECWMF. HOWEVER...BOTH THE GFS
AND ECMWF ARE TRENDING TOWARD A WETTER SYSTEM NOW. SOME -RA POSSIBLY
MIXED WITH A LITTLE SNOW OVER HIGHER TERRAIN WILL PROBABLY REACH THE
W SAT AFTN...THEN SPREAD E SAT NIGHT/SUN. WITH WETTER TRENDS
NOTED...WILL TRENDING POPS UP TO CHC.
MON/TUE...ECMWF HAS BEEN CONSISTENT SHOWING TROF DEVELOPMENT INTO
THE W COAST WITH DOWNSTREAM RIDGE BUILDING INTO THE ROCKIES/WRN
PLAINS WHILE TROF SETTLES INTO THE ERN CONUS. THE GFS IS
CONSIDERABLY MORE PRONOUNCED WITH EASTWARD EXTENT OF RIDGE/HIGHER
HEIGHTS INTO THE GREAT LAKES...BUT THE 12Z GFS IS NOW SHOWING SIGNS
OF HEADING IN THE DIRECTION OF THE ECMWF. WILL LEAN TOWARD THE MORE
CONSISTENT ECMWF WHICH TYPICALLY VERIFIES BETTER. RESULT IS A COOLER
THAN GFS SCENARIO...BUT STILL CLOSE TO NORMAL FOR TEMPS. IF ANY
MINOR WAVES TRACK SE ACROSS THE AREA INTO THE ERN TROF...THERE MAY
BE SOME SCT LIGHT -SHRA AT TIMES. AT THIS POINT...NOTHING SUGGESTS
THE NEED FOR AN EXPLICIT MENTION OF PCPN MON OR TUE.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON)
ISSUED AT 138 PM EDT TUE APR 15 2014
DIURNAL HEATING AND THE PRESENCE OF AN UPPER LEVEL TROUGH WILL SUPPORT
-SHSN WITH POTENTIAL FOR CONDITIONS INTO THE MVFR CATEGORY THROUGH 21Z.
AFTER THE DAYTIME HEATING SUBSIDES THIS EVENING...EXPECT CLEARING
WITH VFR CONDITIONS. LOOK FOR CONDITIONS TO LOWER TO IFR AT KIWD BY
LATE WED MORNING AND TO MVFR AT KCMX AND KSAW BTWN 16-18Z WITH THE
ONSET OF SNOW AHEAD OF APPROACHING SYSTEM OVER THE NRN PLAINS.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 531 PM EDT TUE APR 15 2014
WINDS LESS THAN 20 KTS THROUGH TONIGHT WITH SFC HIGH PRES RIDGE OVER
THE AREA. APPROACHING LOW PRESSURE SYSTEM FM THE PLAINS WILL RESULT
IN INCREASING EAST TO NORTHEAST WINDS ON WEDNESDAY. WENT WITH A GALE
WARNING FOR FAR WRN LAKE SUPERIOR WEDNESDAY AFTN INTO THU MORNING AS
WINDS ARE ENHANCED DUE TO CHANNELING AND TERRAIN EFFECTS. WINDS
SHIFT TO THE NORTH-NORTHWEST TO 25 KTS BY THURSDAY AFTERNOON AS THE
LOW WEAKENS WHILE MOVING OVER ERN LK SUPERIOR. EXPECT WINDS STAY BLO
20 KTS FOR THE REST OF THE FORECAST PERIOD.
&&
.HYDROLOGY...
ISSUED AT 531 PM EDT TUE APR 15 2014
RECENT COLDER WEATHER AND CONTINUATION OF COLDER WEATHER FOR THE
NEXT FEW DAYS WILL RESULT IN SLOW RUNOFF OF MELTING SNOW. THUS...
RIVER LEVELS SHOULD NOT SHOW ANY SIGNIFICANT FLUCTUATIONS.
HOWEVER...ICE JAMS COULD BE AN ISSUE AS THEY HAVE BEEN IN SOME
AREAS. HOWEVER...DIMINISHED RUNOFF SHOULD REDUCE THE POTENTIAL FOR
ADDITIONAL ICE JAMS. WIDESPREAD PRECIPITATION IS IN THE FORECAST FOR
WEDNESDAY THROUGH THURSDAY MORNING WITH THE POTENTIAL FOR 0.50 TO
1.25 INCHES OF LIQUID EQUIVALENT PRECIPITATION...GREATEST OVER THE W
HALF OF UPPER MICHIGAN. THIS PRECIP ADDED TO EXISTING SNOWPACK WITH
WATER EQUIVALENT OF 4-9 INCHES WILL RESULT IN ANOTHER PERIOD OF
SNOWMELT RUNOFF/RIVER RISES AND POSSIBLE ICE JAMS ONCE WARMER
TEMPERATURES ARRIVE NEXT WEEK.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
WINTER WEATHER ADVISORY FROM NOON WEDNESDAY TO NOON EDT THURSDAY
FOR MIZ006-013.
WINTER STORM WARNING FROM NOON WEDNESDAY TO 11 AM EDT THURSDAY
FOR MIZ004-084.
WINTER STORM WARNING FROM NOON WEDNESDAY TO NOON EDT THURSDAY
FOR MIZ005.
WINTER STORM WARNING FROM 11 AM EDT /10 AM CDT/ WEDNESDAY TO 11
AM EDT /10 AM CDT/ THURSDAY FOR MIZ002-009>011.
WINTER STORM WARNING FROM 2 PM WEDNESDAY TO NOON EDT THURSDAY
FOR MIZ001-003.
WINTER WEATHER ADVISORY FROM 9 AM WEDNESDAY TO 10 AM CDT
THURSDAY FOR MIZ012.
LAKE SUPERIOR...
GALE WARNING FROM 2 PM EDT /1 PM CDT/ WEDNESDAY TO 11 AM EDT /10
AM CDT/ THURSDAY FOR LSZ162.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...VOSS
LONG TERM...ROLFSON
AVIATION...VOSS
MARINE...VOSS
HYDROLOGY...ROLFSON
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
157 PM EDT TUE APR 15 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 507 AM EDT TUE APR 15 2014
WV IMAGERY AND RUC ANALYSIS INDICATED A MID/UPPER LEVEL TROUGH FROM
HUDSON BAY THROUGH THE WRN GREAT LAKES AND THE MID MS VALLEY INTO
ERN TX. A WEAK SHRTWV INTO WRN LAKE SUPERIOR SUPPORTED SOME ISOLD
-SHSN TO NEAR IWD WHILE ANOTHER WEAK SHRTWV OVER CNTRL MANTIOBA
INTO NW ONTARIO WAS SLIDING TO THE SE TOWARD WRN LAKE SUPERIOR. AT
THE SFC...NRLY FLOW PREVAILED BTWN A RIDGE EXTENDINGD FROM MANTIOBA
THROUGH THE ERN DAKOTAS AND A TROUGH FROM THE ERN LAKES INTO SRN
QUEBEC. THE NORTH WINDS AND 850 MB TEMPS TO AROUND -17C SUPPORTED
SOME LIGHT LES TO NEAR P53 DESPITE THE EXTENSIVE ICE COVER OVER THE
ERN LAKE.
TODAY...THE UPSTREAM SFC RIDGE WILL BUILD INTO THE WRN LAKES
TODAY BRINGING DIMINISHING WINDS. THIS SHOULD LIMIT OR END THE LES
THIS MORNING OVER THE EAST. SOME ISOLD -SHSN ASSOCIATED WITH THE WRN
LAKE SHRTWV ARE EXPECTED SPREAD INTO THE WRN CWA THIS MORNING. WITH
DAYTIME HEATING...LOW LEVEL LAPSE RATES TO 8-9C/KM WITH 850/700 MB
TEMPS OF -17C/-27C WILL SUPPORT SCT DIURNAL SNOW SHOWERS OVER MAINLY
WEST AND CNTRL UPPER MI. SOME INLAND LOCATIONS COULD SEE A DUSTING
TO AROUND A HALF INCH. OTHERWISE...UNSEASONABLY COLD CONDITIONS WILL
PREVAIL WITH MAX TEMPS IN THE MID 20S TO LOWER 30S WHICH WILL BE
NEAR OR BELOW THE RECORD LOW HIGH TEMP OF 27 FOR THE NWS OFFICE.
TONIGHT...ANY LEFTOVER DIURNAL SHSN OVER S CNTRL UPPER MI
DIMINISH...PARTLY CLOUDY SKIES AND LIGHT WINDS WILL ALLOW TEMPS TO
FALL INTO THE 8F TO 15F RANGE OVERNIGHT. TEMPS MAY CLIMB LATE AS
CLOUDS INCREASE AHEAD OF THE APPROACHING LOW PRESSURE SYSTEM. WAA
LIGHT SNOW WITH INCREASING 280K-290K ISENTROPIC LIFT IS EXPECTED TO
REMAIN MAINLY WEST OF UPPER MI BUT MAY SLIDE INTO THE FAR WEST LATE.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 459 AM EDT TUE APR 15 2014
...POTENTIAL WINTER STORM STILL ON TRACK FOR WEDNESDAY INTO
THURSDAY...
SHORTWAVE CURRENTLY CROSSING SOUTHERN BRITISH COLUMBIA IS FEATURE OF
INTEREST THAT HELPS TO FOCUS SFC LOW ACROSS THE NORTHERN PLAINS BY
TONIGHT. WARM AIR ADVECTION AND ISENTROPIC ASCENT ALONG AND AHEAD OF
THE LOW AND INVERTED SFC TROUGH SHOULD SUPPORT EXPANDING SHIELD OF
SNOW VCNTY OF CNTRL MINNESOTA INTO NORTHWEST WI LATE TONIGHT THROUGH
DAYBREAK ON WEDNESDAY. IF THERE IS ANY TREND IN MODELS IT IS FOR A
SLOWER ARRIVAL OF QPF/SNOW INTO WESTERN UPR MICHIGAN BTWN 12Z-18Z ON
WEDNESDAY. TREND IS NOTHING TOO DRASTIC THOUGH...SO CHANGES TO THIS
PART OF THE FORECAST WERE RELATIVELY MINOR. SFC TROUGH EDGES CLOSER
TO UPR MICHIGAN ON WEDNESDAY AFTN. ISENTROPIC ASCENT MAXIMIZED ON
290K SFC /H775-H650/ AND 285K SFC /H8-H7/ SURGES SOUTH TO NORTH
ACROSS UPR MICHIGAN ROUGHLY 15Z-03Z...THOUGH GFS/NAM REMAIN QUICKER
WITH THIS INITIAL PUSH OF WHAT WILL ESSENTIALLY BE MAINLY SNOW FOR
CWA. H7 MIXING RATIOS IN 2.5-2.75G/KG RANGE SUGGESTS 12 HOUR SNOW
AMOUNTS NEARING 6 INCHES. SUPPOSE ACTUAL SNOW AMOUNTS COULD BE
HELD DOWN SOME AS SNOW ARRIVES DURING THE DAYTIME WHEN SOME INSOLATION
COULD LIMIT ACCUMS ESPECIALLY ON HIGHER TRAFFIC/TRAVELLED ROADS.
THUS OVERALL POSSIBLE IMPACT FROM THE SNOW COULD BE MITIGATED SOME
COMPARED TO IF THE SNOW ARRIVED DURING THE NIGHTTIME HOURS.
ULTIMATELY IT ALL DEPENDS ON SNOWFALL RATES...WITH HIGHER RATES
ALLOWING FOR SLUSHY ACCUMS EVEN ON THE PRIMARY ROADS.
NAM QPF STILL APPEARS OVERDONE ESPECIALLY WHEN COMPARED TO ITS OWN
MIXING RATIOS. DO NOT DOUBT THAT AREAS OVER MAINLY WESTERN TIER OF
CWA WILL SEE HIGHER QPF/SNOW DUE TO INCREASING AND FAIRLY ROBUST
H8-H7 FGEN AND STRONG FN VECTOR CONVERGENCE. FAR WEST TOWARD KEWEENAW
SEEMS IN LINE FOR THE HIGHEST PROBABILITY OF THIS ADDITIONAL FORCING
WHICH COULD BE SUPPLEMENTED WITH INSTABILITY AS SOME NEGATIVE EPV IS
PRESENT ATOP THE FGEN. NET RESULT IS POTENTIAL FOR BANDED SNOWFALL
SOMEWHERE IN THE WESTERN CWA.
EVEN TRENDING AWAY FM THE NAM 1 INCH PLUS QPF AMOUNTS...BLEND OF GFS
AND ECMWF WOULD SUGGEST SOME AREAS WILL SEE 0.8 INCH OF TOTAL QPF.
THIS LINES UP WELL WITH SREF PROBS SHOWING OVER 70 PCT CHANCE OF
EXCEEDING 0.50 INCH BUT NOT EVEN REACHING 10 PCT PROBS OF SEEING 1
INCH OF LIQUID. SOUNDINGS OVERALL SHOW BULK OF LIFT OCCURRING IN THE
DGZ UP OVER 10KFT AGL. LIFT BLO THIS LAYER IN TEMPS WARMER THAN -10C
WILL LOWER SLR/S SLIGHTLY. EXPECTING MOST AREAS CENTERED IN THE 12:1
RANGE...A BIT HIGHER IN THE FGEN AREA AND POSSIBLY A BIT LOWER
FARTHER SOUTH AND EAST IN THE CWA WITH WARMER TEMPS BLO 5KFT. WHAT
ALL THIS MEANS FOR SNOW AMOUNTS IS DECENT LIKLIHOOD OF SEEING TOTALS
OVER 10 INCHES OVER WEST VCNTY OF PERSISTENT FGEN FORCING...BUT
PROBABLY MORE IN THE 7 TO 10 RANGE FARTHER EAST INTO CNTRL CWA.
SINCE THE SNOW DOES NOT ARRIVE UNTIL ON WEDNESDAY AND GIVEN
UNCERTAINTY IN THE SNOW AMOUNTS OVR THE CNTRL CWA...COORD WITH GRB
AND DLH AND WILL BE LEAVING WINTER STORM WATCH AS IS ATTM.
FARTHER SOUTH AND EAST IN THE CWA...SOUNDINGS AND 1000-850MB AND
850-700MB THICKNESSES INDICATE INITIAL SURGE OF PRECIPITATION
WEDNESDAY AFTN WILL BE GENERALLY SNOW. ENOUGH WARMING OCCURS SOUTH
OF LINE FM KIMT TO KERY WEDNESDAY NIGHT INTO THURSDAY TO RESULT IN
RAIN/SNOW MIX OR POSSIBLE CHANGEOVER TO RAIN. BEST CHANCE FOR ONLY
RAIN REMAINS AT KMNM AS WBZERO HEIGHT INCREASE OVER 2000FT AGL. MAY
SEE MORE AREAS CHANGE TO RAIN BY THURSDAY AFTN AS TEMPS RISE INTO
THE UPPER 30S...BUT HEAVIER PRECIP IS EXPECTED TO BE EAST AND NORTH
OF CWA BY THAT TIME. SOUNDINGS INDICATE EXITING DEEP MOISTURE MAY
RESULT IN SITUATION WHERE DRIZZLE OR FLURRIES ARE MAIN PCPN THAT IS
OCCURRING BY THURSDAY AFTN. SNOW AMOUNTS IN THE EAST SHOULD BE HELD
DOWN OVERALL WITH THIS SYSTEM DUE TO THE WARMER AIR BLO H85 WORKING
IN LATER WEDNESDAY NIGHT INTO THURSDAY. ATTM THINKING AREAS EAST OF
THE WATCH WILL NEED AN ADVY. MODELS DO SHOW SOME DISAGREEMENT ON
THIS ASPECT OF THE SYSTEM THOUGH. GFS/NAM/ECMWF GENERALLY IN LINE
WITH DIMINISHING PRECIP TREND ON THURSDAY...WHILE THE GEM-NH AND
UKMET ARE SLOWER AND FARTHER SOUTH WITH PRIMARY AREA OF HEAVIER
SNOW. SHIFTS TODAY AND TONIGHT WILL NEED TO PIN THIS DOWN FURTHER.
RIGHT NOW THE FORECAST LEANED TOWARD GFS/ECMWF BLEND WHICH WAS ALSO
PREFERRED BY HPC.
NOT A WHOLE LOT OF DETAIL FOR THE EXTENDED PERIOD AS MAIN FOCUS WAS
ON THE HIGHER IMPACT WEDNESDAY/THURSDAY WEATHER. PROBABLY JUST AS
WELL TO AS MODELS ARE STRUGGLING MIGHTILY ON SPECIFICS FOR THE
WEEKEND.
ONE TREND THAT WAS ACTED UPON WAS TO GO WITH DRIER FORECAST FOR
FRIDAY AND FRIDAY NIGHT AS GFS WHICH WAS SHOWING WRAPPED UP SYSTEM
ACROSS THE UPR LAKES A COUPLE DAYS AGO IS NOW SHUNTING PRECIP WELL
TO THE SOUTH AND EAST OVER THE CNTRL GREAT LAKES ALONG PRIMARY H85
MOISTURE AXIS. THIS AGREES WELL WITH GEM-NH AND ECMWF. HIGH PRESSURE
AND DRY WEATHER DOMINATES SOUTH CNTRL CANADA INTO UPPER GREAT LAKES.
THUS DROPPED POPS ON FRIDAY AND FRIDAY NIGHT. SHOULD STAY SEASONABLY
CHILLY THOUGH WITH MID 30S NORTH AND LOWER 40S SOUTH AS NE WINDS
FLOW OFF THE ICY WATERS OF LK SUPERIOR AND THERE COULD BE MID CLOUDS
ON THE NORTHWEST SIDE OF THE FRONTAL BOUNDARY OVR THE CNTRL GREAT
LAKES.
MODEL CONSENSUS WAS USED FOR SATURDAY/EASTER SUNDAY/MONDAY. ECMWF
AND GEM-NH TRENDING WETTER FOR SATURDAY NIGHT INTO SUNDAY. PTYPE
WOULD MOSTLY BE RAIN...WITH MIX OF RAIN/SNOW POSSIBLE ON SATURDAY
NIGHT AS COOLER LOW-LEVEL AIR GRADUALLY RETREATS. GFS NOT AS EXCITED
ON THE OVERALL PCPN CHANCES. FORECAST CAME OUT WITH SLIGHT CHANCES
WITH MOSTLY CLOUDY SKIES. THIS WORKS FOR NOW AS THE CONSISTENCY IN
THE MODELS IS LESS THAN DESIRED FOR SURE. TEMPS INDICATE GRADUAL
WARMING TREND...BUT COULD SEE WARMER TEMPS THAN FORECAST IF ANY OF
THESE DAYS ENDS UP DRY WITH SOME SUNSHINE.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON)
ISSUED AT 138 PM EDT TUE APR 15 2014
DIURNAL HEATING AND THE PRESENCE OF AN UPPER LEVEL TROUGH WILL SUPPORT
-SHSN WITH POTENTIAL FOR CONDITIONS INTO THE MVFR CATEGORY THROUGH 21Z.
AFTER THE DAYTIME HEATING SUBSIDES THIS EVENING...EXPECT CLEARING
WITH VFR CONDITIONS. LOOK FOR CONDITIONS TO LOWER TO IFR AT KIWD BY
LATE WED MORNING AND TO MVFR AT KCMX AND KSAW BTWN 16-18Z WITH THE
ONSET OF SNOW AHEAD OF APPROACHING SYSTEM OVER THE NRN PLAINS.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 459 AM EDT TUE APR 15 2014
WINDS LESS THAN 20 KTS THROUGH TONIGHT. APPROACHING LOW PRESSURE
SYSTEM RESULTS IN INCREASING EAST TO NORTHEAST WINDS ON WEDNESDAY.
30 KTS WITH GALE GUSTS SEEMS LIKELY OVER FAR WESTERN LK SUPERIOR
WEDNESDAY AFTN INTO WEDNESDAY EVENING AS WINDS ARE ENHANCED DUE TO
CHANNELING AND TERRAIN EFFECTS. WINDS SHIFT TO THE NORTH-NORTHWEST
TO 25 KTS ON THURSDAY AS THE LOW WEAKENS WHILE MOVING TO THE EAST OF
LK SUPERIOR. WINDS STAY BLO 20 KTS FOR THE REST OF THE FORECAST
PERIOD.
&&
.HYDROLOGY...
ISSUED AT 459 AM EDT TUE APR 15 2014
GIVEN COLDER TEMPERATURES OVER THE NEXT COUPLE OF DAYS...EXPECT
SLOWER RUNOFF OF MELTING SNOW TO REDUCE THE POTENTIAL FOR ADDITIONAL
ICE JAMS. WIDESPREAD PRECIPITATION IS IN THE FORECAST FOR WEDNESDAY
THROUGH THURSDAY WITH THE POTENTIAL FOR AN ADDITIONAL INCH OF LIQUID
EQUIVALENT PRECIPITATION OVER WESTERN UPPER MICHIGAN. THIS PRECIP
ADDED TO EXISTING SNOWPACK WITH WATER EQUIVALENT OF 4-9 INCHES WILL
RESULT IN ANOTHER PERIOD OF SNOWMELT/RUNOFF AND POSSIBLE ICE JAMS ONCE
WARMER TEMPERATURES MOVE BACK INTO THE REGION NEXT WEEK.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
WINTER STORM WATCH FROM WEDNESDAY MORNING THROUGH THURSDAY
MORNING FOR MIZ001>005-009>011-084.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...JLB
LONG TERM...JLA
AVIATION...VOSS
MARINE...JLA
HYDROLOGY...JLA
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
728 AM EDT TUE APR 15 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 507 AM EDT TUE APR 15 2014
WV IMAGERY AND RUC ANALYSIS INDICATED A MID/UPPER LEVEL TROUGH FROM
HUDSON BAY THROUGH THE WRN GREAT LAKES AND THE MID MS VALLEY INTO
ERN TX. A WEAK SHRTWV INTO WRN LAKE SUPERIOR SUPPORTED SOME ISOLD
-SHSN TO NEAR IWD WHILE ANOTHER WEAK SHRTWV OVER CNTRL MANTIOBA
INTO NW ONTARIO WAS SLIDING TO THE SE TOWARD WRN LAKE SUPERIOR. AT
THE SFC...NRLY FLOW PREVAILED BTWN A RIDGE EXTENDINGD FROM MANTIOBA
THROUGH THE ERN DAKOTAS AND A TROUGH FROM THE ERN LAKES INTO SRN
QUEBEC. THE NORTH WINDS AND 850 MB TEMPS TO AROUND -17C SUPPORTED
SOME LIGHT LES TO NEAR P53 DESPITE THE EXTENSIVE ICE COVER OVER THE
ERN LAKE.
TODAY...THE UPSTREAM SFC RIDGE WILL BUILD INTO THE WRN LAKES
TODAY BRINGING DIMINISHING WINDS. THIS SHOULD LIMIT OR END THE LES
THIS MORNING OVER THE EAST. SOME ISOLD -SHSN ASSOCIATED WITH THE WRN
LAKE SHRTWV ARE EXPECTED SPREAD INTO THE WRN CWA THIS MORNING. WITH
DAYTIME HEATING...LOW LEVEL LAPSE RATES TO 8-9C/KM WITH 850/700 MB
TEMPS OF -17C/-27C WILL SUPPORT SCT DIURNAL SNOW SHOWERS OVER MAINLY
WEST AND CNTRL UPPER MI. SOME INLAND LOCATIONS COULD SEE A DUSTING
TO AROUND A HALF INCH. OTHERWISE...UNSEASONABLY COLD CONDITIONS WILL
PREVAIL WITH MAX TEMPS IN THE MID 20S TO LOWER 30S WHICH WILL BE
NEAR OR BELOW THE RECORD LOW HIGH TEMP OF 27 FOR THE NWS OFFICE.
TONIGHT...ANY LEFTOVER DIURNAL SHSN OVER S CNTRL UPPER MI
DIMINISH...PARTLY CLOUDY SKIES AND LIGHT WINDS WILL ALLOW TEMPS TO
FALL INTO THE 8F TO 15F RANGE OVERNIGHT. TEMPS MAY CLIMB LATE AS
CLOUDS INCREASE AHEAD OF THE APPROACHING LOW PRESSURE SYSTEM. WAA
LIGHT SNOW WITH INCREASING 280K-290K ISENTROPIC LIFT IS EXPECTED TO
REMAIN MAINLY WEST OF UPPER MI BUT MAY SLIDE INTO THE FAR WEST LATE.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 459 AM EDT TUE APR 15 2014
...POTENTIAL WINTER STORM STILL ON TRACK FOR WEDNESDAY INTO
THURSDAY...
SHORTWAVE CURRENTLY CROSSING SOUTHERN BRITISH COLUMBIA IS FEATURE OF
INTEREST THAT HELPS TO FOCUS SFC LOW ACROSS THE NORTHERN PLAINS BY
TONIGHT. WARM AIR ADVECTION AND ISENTROPIC ASCENT ALONG AND AHEAD OF
THE LOW AND INVERTED SFC TROUGH SHOULD SUPPORT EXPANDING SHIELD OF
SNOW VCNTY OF CNTRL MINNESOTA INTO NORTHWEST WI LATE TONIGHT THROUGH
DAYBREAK ON WEDNESDAY. IF THERE IS ANY TREND IN MODELS IT IS FOR A
SLOWER ARRIVAL OF QPF/SNOW INTO WESTERN UPR MICHIGAN BTWN 12Z-18Z ON
WEDNESDAY. TREND IS NOTHING TOO DRASTIC THOUGH...SO CHANGES TO THIS
PART OF THE FORECAST WERE RELATIVELY MINOR. SFC TROUGH EDGES CLOSER
TO UPR MICHIGAN ON WEDNESDAY AFTN. ISENTROPIC ASCENT MAXIMIZED ON
290K SFC /H775-H650/ AND 285K SFC /H8-H7/ SURGES SOUTH TO NORTH
ACROSS UPR MICHIGAN ROUGHLY 15Z-03Z...THOUGH GFS/NAM REMAIN QUICKER
WITH THIS INITIAL PUSH OF WHAT WILL ESSENTIALLY BE MAINLY SNOW FOR
CWA. H7 MIXING RATIOS IN 2.5-2.75G/KG RANGE SUGGESTS 12 HOUR SNOW
AMOUNTS NEARING 6 INCHES. SUPPOSE ACTUAL SNOW AMOUNTS COULD BE
HELD DOWN SOME AS SNOW ARRIVES DURING THE DAYTIME WHEN SOME INSOLATION
COULD LIMIT ACCUMS ESPECIALLY ON HIGHER TRAFFIC/TRAVELLED ROADS.
THUS OVERALL POSSIBLE IMPACT FROM THE SNOW COULD BE MITIGATED SOME
COMPARED TO IF THE SNOW ARRIVED DURING THE NIGHTTIME HOURS.
ULTIMATELY IT ALL DEPENDS ON SNOWFALL RATES...WITH HIGHER RATES
ALLOWING FOR SLUSHY ACCUMS EVEN ON THE PRIMARY ROADS.
NAM QPF STILL APPEARS OVERDONE ESPECIALLY WHEN COMPARED TO ITS OWN
MIXING RATIOS. DO NOT DOUBT THAT AREAS OVER MAINLY WESTERN TIER OF
CWA WILL SEE HIGHER QPF/SNOW DUE TO INCREASING AND FAIRLY ROBUST
H8-H7 FGEN AND STRONG FN VECTOR CONVERGENCE. FAR WEST TOWARD KEWEENAW
SEEMS IN LINE FOR THE HIGHEST PROBABILITY OF THIS ADDITIONAL FORCING
WHICH COULD BE SUPPLEMENTED WITH INSTABILITY AS SOME NEGATIVE EPV IS
PRESENT ATOP THE FGEN. NET RESULT IS POTENTIAL FOR BANDED SNOWFALL
SOMEWHERE IN THE WESTERN CWA.
EVEN TRENDING AWAY FM THE NAM 1 INCH PLUS QPF AMOUNTS...BLEND OF GFS
AND ECMWF WOULD SUGGEST SOME AREAS WILL SEE 0.8 INCH OF TOTAL QPF.
THIS LINES UP WELL WITH SREF PROBS SHOWING OVER 70 PCT CHANCE OF
EXCEEDING 0.50 INCH BUT NOT EVEN REACHING 10 PCT PROBS OF SEEING 1
INCH OF LIQUID. SOUNDINGS OVERALL SHOW BULK OF LIFT OCCURRING IN THE
DGZ UP OVER 10KFT AGL. LIFT BLO THIS LAYER IN TEMPS WARMER THAN -10C
WILL LOWER SLR/S SLIGHTLY. EXPECTING MOST AREAS CENTERED IN THE 12:1
RANGE...A BIT HIGHER IN THE FGEN AREA AND POSSIBLY A BIT LOWER
FARTHER SOUTH AND EAST IN THE CWA WITH WARMER TEMPS BLO 5KFT. WHAT
ALL THIS MEANS FOR SNOW AMOUNTS IS DECENT LIKLIHOOD OF SEEING TOTALS
OVER 10 INCHES OVER WEST VCNTY OF PERSISTENT FGEN FORCING...BUT
PROBABLY MORE IN THE 7 TO 10 RANGE FARTHER EAST INTO CNTRL CWA.
SINCE THE SNOW DOES NOT ARRIVE UNTIL ON WEDNESDAY AND GIVEN
UNCERTAINTY IN THE SNOW AMOUNTS OVR THE CNTRL CWA...COORD WITH GRB
AND DLH AND WILL BE LEAVING WINTER STORM WATCH AS IS ATTM.
FARTHER SOUTH AND EAST IN THE CWA...SOUNDINGS AND 1000-850MB AND
850-700MB THICKNESSES INDICATE INITIAL SURGE OF PRECIPITATION
WEDNESDAY AFTN WILL BE GENERALLY SNOW. ENOUGH WARMING OCCURS SOUTH
OF LINE FM KIMT TO KERY WEDNESDAY NIGHT INTO THURSDAY TO RESULT IN
RAIN/SNOW MIX OR POSSIBLE CHANGEOVER TO RAIN. BEST CHANCE FOR ONLY
RAIN REMAINS AT KMNM AS WBZERO HEIGHT INCREASE OVER 2000FT AGL. MAY
SEE MORE AREAS CHANGE TO RAIN BY THURSDAY AFTN AS TEMPS RISE INTO
THE UPPER 30S...BUT HEAVIER PRECIP IS EXPECTED TO BE EAST AND NORTH
OF CWA BY THAT TIME. SOUNDINGS INDICATE EXITING DEEP MOISTURE MAY
RESULT IN SITUATION WHERE DRIZZLE OR FLURRIES ARE MAIN PCPN THAT IS
OCCURRING BY THURSDAY AFTN. SNOW AMOUNTS IN THE EAST SHOULD BE HELD
DOWN OVERALL WITH THIS SYSTEM DUE TO THE WARMER AIR BLO H85 WORKING
IN LATER WEDNESDAY NIGHT INTO THURSDAY. ATTM THINKING AREAS EAST OF
THE WATCH WILL NEED AN ADVY. MODELS DO SHOW SOME DISAGREEMENT ON
THIS ASPECT OF THE SYSTEM THOUGH. GFS/NAM/ECMWF GENERALLY IN LINE
WITH DIMINISHING PRECIP TREND ON THURSDAY...WHILE THE GEM-NH AND
UKMET ARE SLOWER AND FARTHER SOUTH WITH PRIMARY AREA OF HEAVIER
SNOW. SHIFTS TODAY AND TONIGHT WILL NEED TO PIN THIS DOWN FURTHER.
RIGHT NOW THE FORECAST LEANED TOWARD GFS/ECMWF BLEND WHICH WAS ALSO
PREFERRED BY HPC.
NOT A WHOLE LOT OF DETAIL FOR THE EXTENDED PERIOD AS MAIN FOCUS WAS
ON THE HIGHER IMPACT WEDNESDAY/THURSDAY WEATHER. PROBABLY JUST AS
WELL TO AS MODELS ARE STRUGGLING MIGHTILY ON SPECIFICS FOR THE
WEEKEND.
ONE TREND THAT WAS ACTED UPON WAS TO GO WITH DRIER FORECAST FOR
FRIDAY AND FRIDAY NIGHT AS GFS WHICH WAS SHOWING WRAPPED UP SYSTEM
ACROSS THE UPR LAKES A COUPLE DAYS AGO IS NOW SHUNTING PRECIP WELL
TO THE SOUTH AND EAST OVER THE CNTRL GREAT LAKES ALONG PRIMARY H85
MOISTURE AXIS. THIS AGREES WELL WITH GEM-NH AND ECMWF. HIGH PRESSURE
AND DRY WEATHER DOMINATES SOUTH CNTRL CANADA INTO UPPER GREAT LAKES.
THUS DROPPED POPS ON FRIDAY AND FRIDAY NIGHT. SHOULD STAY SEASONABLY
CHILLY THOUGH WITH MID 30S NORTH AND LOWER 40S SOUTH AS NE WINDS
FLOW OFF THE ICY WATERS OF LK SUPERIOR AND THERE COULD BE MID CLOUDS
ON THE NORTHWEST SIDE OF THE FRONTAL BOUNDARY OVR THE CNTRL GREAT
LAKES.
MODEL CONSENSUS WAS USED FOR SATURDAY/EASTER SUNDAY/MONDAY. ECMWF
AND GEM-NH TRENDING WETTER FOR SATURDAY NIGHT INTO SUNDAY. PTYPE
WOULD MOSTLY BE RAIN...WITH MIX OF RAIN/SNOW POSSIBLE ON SATURDAY
NIGHT AS COOLER LOW-LEVEL AIR GRADUALLY RETREATS. GFS NOT AS EXCITED
ON THE OVERALL PCPN CHANCES. FORECAST CAME OUT WITH SLIGHT CHANCES
WITH MOSTLY CLOUDY SKIES. THIS WORKS FOR NOW AS THE CONSISTENCY IN
THE MODELS IS LESS THAN DESIRED FOR SURE. TEMPS INDICATE GRADUAL
WARMING TREND...BUT COULD SEE WARMER TEMPS THAN FORECAST IF ANY OF
THESE DAYS ENDS UP DRY WITH SOME SUNSHINE.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z WEDNESDAY MORNING)
ISSUED AT 728 AM EDT TUE APR 15 2014
THE COMBINATION OF AN UPPER LEVEL DISTURBANCE AND COLD LIGHT NNW
FLOW OVER PARTIAL OPEN WATERS OF WRN LAKE SUPERIOR WILL BE ENOUGH TO
SUPPORT SCT -SHSN THIS MORNING WITH OCNL CONDITIONS INTO THE MVFR
RANGE AT IWD/CMX. OTHERWISE...DIURNAL HEATING WILL ALSO SUPPORT
ADDITIONAL -SHSN WITH POTENTIAL FOR CONDITIONS NEAR INTO THE MVFR
CATEGORY. AFTER THE DAYTIME HEATING SUBSIDES THIS EVENING...EXPECT CLEARING
WITH VFR CONDITIONS.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 459 AM EDT TUE APR 15 2014
WINDS LESS THAN 20 KTS THROUGH TONIGHT. APPROACHING LOW PRESSURE
SYSTEM RESULTS IN INCREASING EAST TO NORTHEAST WINDS ON WEDNESDAY.
30 KTS WITH GALE GUSTS SEEMS LIKELY OVER FAR WESTERN LK SUPERIOR
WEDNESDAY AFTN INTO WEDNESDAY EVENING AS WINDS ARE ENHANCED DUE TO
CHANNELING AND TERRAIN EFFECTS. WINDS SHIFT TO THE NORTH-NORTHWEST
TO 25 KTS ON THURSDAY AS THE LOW WEAKENS WHILE MOVING TO THE EAST OF
LK SUPERIOR. WINDS STAY BLO 20 KTS FOR THE REST OF THE FORECAST
PERIOD.
&&
.HYDROLOGY...
ISSUED AT 459 AM EDT TUE APR 15 2014
GIVEN COLDER TEMPERATURES OVER THE NEXT COUPLE OF DAYS...EXPECT
SLOWER RUNOFF OF MELTING SNOW TO REDUCE THE POTENTIAL FOR ADDITIONAL
ICE JAMS. WIDESPREAD PRECIPITATION IS IN THE FORECAST FOR WEDNESDAY
THROUGH THURSDAY WITH THE POTENTIAL FOR AN ADDITIONAL INCH OF LIQUID
EQUIVALENT PRECIPITATION OVER WESTERN UPPER MICHIGAN. THIS PRECIP
ADDED TO EXISTING SNOWPACK WITH WATER EQUIVALENT OF 4-9 INCHES WILL
RESULT IN ANOTHER PERIOD OF SNOWMELT/RUNOFF AND POSSIBLE ICE JAMS ONCE
WARMER TEMPERATURES MOVE BACK INTO THE REGION NEXT WEEK.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
WINTER STORM WATCH FROM WEDNESDAY MORNING THROUGH THURSDAY
MORNING FOR MIZ001>005-009>011-084.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...JLB
LONG TERM...JLA
AVIATION...JLB
MARINE...JLA
HYDROLOGY...JLA
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
508 AM EDT TUE APR 15 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 507 AM EDT TUE APR 15 2014
WV IMAGERY AND RUC ANALYSIS INDICATED A MID/UPPER LEVEL TROUGH FROM
HUDSON BAY THROUGH THE WRN GREAT LAKES AND THE MID MS VALLEY INTO
ERN TX. A WEAK SHRTWV INTO WRN LAKE SUPERIOR SUPPORTED SOME ISOLD
-SHSN TO NEAR IWD WHILE ANOTHER WEAK SHRTWV OVER CNTRL MANTIOBA
INTO NW ONTARIO WAS SLIDING TO THE SE TOWARD WRN LAKE SUPERIOR. AT
THE SFC...NRLY FLOW PREVAILED BTWN A RIDGE EXTENDINGD FROM MANTIOBA
THROUGH THE ERN DAKOTAS AND A TROUGH FROM THE ERN LAKES INTO SRN
QUEBEC. THE NORTH WINDS AND 850 MB TEMPS TO AROUND -17C SUPPORTED
SOME LIGHT LES TO NEAR P53 DESPITE THE EXTENSIVE ICE COVER OVER THE
ERN LAKE.
TODAY...THE UPSTREAM SFC RIDGE WILL BUILD INTO THE WRN LAKES
TODAY BRINGING DIMINISHING WINDS. THIS SHOULD LIMIT OR END THE LES
THIS MORNING OVER THE EAST. SOME ISOLD -SHSN ASSOCIATED WITH THE WRN
LAKE SHRTWV ARE EXPECTED SPREAD INTO THE WRN CWA THIS MORNING. WITH
DAYTIME HEATING...LOW LEVEL LAPSE RATES TO 8-9C/KM WITH 850/700 MB
TEMPS OF -17C/-27C WILL SUPPORT SCT DIURNAL SNOW SHOWERS OVER MAINLY
WEST AND CNTRL UPPER MI. SOME INLAND LOCATIONS COULD SEE A DUSTING
TO AROUND A HALF INCH. OTHERWISE...UNSEASONABLY COLD CONDITIONS WILL
PREVAIL WITH MAX TEMPS IN THE MID 20S TO LOWER 30S WHICH WILL BE
NEAR OR BELOW THE RECORD LOW HIGH TEMP OF 27 FOR THE NWS OFFICE.
TONIGHT...ANY LEFTOVER DIURNAL SHSN OVER S CNTRL UPPER MI
DIMINISH...PARTLY CLOUDY SKIES AND LIGHT WINDS WILL ALLOW TEMPS TO
FALL INTO THE 8F TO 15F RANGE OVERNIGHT. TEMPS MAY CLIMB LATE AS
CLOUDS INCREASE AHEAD OF THE APPROACHING LOW PRESSURE SYSTEM. WAA
LIGHT SNOW WITH INCREASING 280K-290K ISENTROPIC LIFT IS EXPECTED TO
REMAIN MAINLY WEST OF UPPER MI BUT MAY SLIDE INTO THE FAR WEST LATE.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 459 AM EDT TUE APR 15 2014
...POTENTIAL WINTER STORM STILL ON TRACK FOR WEDNESDAY INTO
THURSDAY...
SHORTWAVE CURRENTLY CROSSING SOUTHERN BRITISH COLUMBIA IS FEATURE OF
INTEREST THAT HELPS TO FOCUS SFC LOW ACROSS THE NORTHERN PLAINS BY
TONIGHT. WARM AIR ADVECTION AND ISENTROPIC ASCENT ALONG AND AHEAD OF
THE LOW AND INVERTED SFC TROUGH SHOULD SUPPORT EXPANDING SHIELD OF
SNOW VCNTY OF CNTRL MINNESOTA INTO NORTHWEST WI LATE TONIGHT THROUGH
DAYBREAK ON WEDNESDAY. IF THERE IS ANY TREND IN MODELS IT IS FOR A
SLOWER ARRIVAL OF QPF/SNOW INTO WESTERN UPR MICHIGAN BTWN 12Z-18Z ON
WEDNESDAY. TREND IS NOTHING TOO DRASTIC THOUGH...SO CHANGES TO THIS
PART OF THE FORECAST WERE RELATIVELY MINOR. SFC TROUGH EDGES CLOSER
TO UPR MICHIGAN ON WEDNESDAY AFTN. ISENTROPIC ASCENT MAXIMIZED ON
290K SFC /H775-H650/ AND 285K SFC /H8-H7/ SURGES SOUTH TO NORTH
ACROSS UPR MICHIGAN ROUGHLY 15Z-03Z...THOUGH GFS/NAM REMAIN QUICKER
WITH THIS INITIAL PUSH OF WHAT WILL ESSENTIALLY BE MAINLY SNOW FOR
CWA. H7 MIXING RATIOS IN 2.5-2.75G/KG RANGE SUGGESTS 12 HOUR SNOW
AMOUNTS NEARING 6 INCHES. SUPPOSE ACTUAL SNOW AMOUNTS COULD BE
HELD DOWN SOME AS SNOW ARRIVES DURING THE DAYTIME WHEN SOME INSOLATION
COULD LIMIT ACCUMS ESPECIALLY ON HIGHER TRAFFIC/TRAVELLED ROADS.
THUS OVERALL POSSIBLE IMPACT FROM THE SNOW COULD BE MITIGATED SOME
COMPARED TO IF THE SNOW ARRIVED DURING THE NIGHTTIME HOURS.
ULTIMATELY IT ALL DEPENDS ON SNOWFALL RATES...WITH HIGHER RATES
ALLOWING FOR SLUSHY ACCUMS EVEN ON THE PRIMARY ROADS.
NAM QPF STILL APPEARS OVERDONE ESPECIALLY WHEN COMPARED TO ITS OWN
MIXING RATIOS. DO NOT DOUBT THAT AREAS OVER MAINLY WESTERN TIER OF
CWA WILL SEE HIGHER QPF/SNOW DUE TO INCREASING AND FAIRLY ROBUST
H8-H7 FGEN AND STRONG FN VECTOR CONVERGENCE. FAR WEST TOWARD KEWEENAW
SEEMS IN LINE FOR THE HIGHEST PROBABILITY OF THIS ADDITIONAL FORCING
WHICH COULD BE SUPPLEMENTED WITH INSTABILITY AS SOME NEGATIVE EPV IS
PRESENT ATOP THE FGEN. NET RESULT IS POTENTIAL FOR BANDED SNOWFALL
SOMEWHERE IN THE WESTERN CWA.
EVEN TRENDING AWAY FM THE NAM 1 INCH PLUS QPF AMOUNTS...BLEND OF GFS
AND ECMWF WOULD SUGGEST SOME AREAS WILL SEE 0.8 INCH OF TOTAL QPF.
THIS LINES UP WELL WITH SREF PROBS SHOWING OVER 70 PCT CHANCE OF
EXCEEDING 0.50 INCH BUT NOT EVEN REACHING 10 PCT PROBS OF SEEING 1
INCH OF LIQUID. SOUNDINGS OVERALL SHOW BULK OF LIFT OCCURRING IN THE
DGZ UP OVER 10KFT AGL. LIFT BLO THIS LAYER IN TEMPS WARMER THAN -10C
WILL LOWER SLR/S SLIGHTLY. EXPECTING MOST AREAS CENTERED IN THE 12:1
RANGE...A BIT HIGHER IN THE FGEN AREA AND POSSIBLY A BIT LOWER
FARTHER SOUTH AND EAST IN THE CWA WITH WARMER TEMPS BLO 5KFT. WHAT
ALL THIS MEANS FOR SNOW AMOUNTS IS DECENT LIKLIHOOD OF SEEING TOTALS
OVER 10 INCHES OVER WEST VCNTY OF PERSISTENT FGEN FORCING...BUT
PROBABLY MORE IN THE 7 TO 10 RANGE FARTHER EAST INTO CNTRL CWA.
SINCE THE SNOW DOES NOT ARRIVE UNTIL ON WEDNESDAY AND GIVEN
UNCERTAINTY IN THE SNOW AMOUNTS OVR THE CNTRL CWA...COORD WITH GRB
AND DLH AND WILL BE LEAVING WINTER STORM WATCH AS IS ATTM.
FARTHER SOUTH AND EAST IN THE CWA...SOUNDINGS AND 1000-850MB AND
850-700MB THICKNESSES INDICATE INITIAL SURGE OF PRECIPITATION
WEDNESDAY AFTN WILL BE GENERALLY SNOW. ENOUGH WARMING OCCURS SOUTH
OF LINE FM KIMT TO KERY WEDNESDAY NIGHT INTO THURSDAY TO RESULT IN
RAIN/SNOW MIX OR POSSIBLE CHANGEOVER TO RAIN. BEST CHANCE FOR ONLY
RAIN REMAINS AT KMNM AS WBZERO HEIGHT INCREASE OVER 2000FT AGL. MAY
SEE MORE AREAS CHANGE TO RAIN BY THURSDAY AFTN AS TEMPS RISE INTO
THE UPPER 30S...BUT HEAVIER PRECIP IS EXPECTED TO BE EAST AND NORTH
OF CWA BY THAT TIME. SOUNDINGS INDICATE EXITING DEEP MOISTURE MAY
RESULT IN SITUATION WHERE DRIZZLE OR FLURRIES ARE MAIN PCPN THAT IS
OCCURRING BY THURSDAY AFTN. SNOW AMOUNTS IN THE EAST SHOULD BE HELD
DOWN OVERALL WITH THIS SYSTEM DUE TO THE WARMER AIR BLO H85 WORKING
IN LATER WEDNESDAY NIGHT INTO THURSDAY. ATTM THINKING AREAS EAST OF
THE WATCH WILL NEED AN ADVY. MODELS DO SHOW SOME DISAGREEMENT ON
THIS ASPECT OF THE SYSTEM THOUGH. GFS/NAM/ECMWF GENERALLY IN LINE
WITH DIMINISHING PRECIP TREND ON THURSDAY...WHILE THE GEM-NH AND
UKMET ARE SLOWER AND FARTHER SOUTH WITH PRIMARY AREA OF HEAVIER
SNOW. SHIFTS TODAY AND TONIGHT WILL NEED TO PIN THIS DOWN FURTHER.
RIGHT NOW THE FORECAST LEANED TOWARD GFS/ECMWF BLEND WHICH WAS ALSO
PREFERRED BY HPC.
NOT A WHOLE LOT OF DETAIL FOR THE EXTENDED PERIOD AS MAIN FOCUS WAS
ON THE HIGHER IMPACT WEDNESDAY/THURSDAY WEATHER. PROBABLY JUST AS
WELL TO AS MODELS ARE STRUGGLING MIGHTILY ON SPECIFICS FOR THE
WEEKEND.
ONE TREND THAT WAS ACTED UPON WAS TO GO WITH DRIER FORECAST FOR
FRIDAY AND FRIDAY NIGHT AS GFS WHICH WAS SHOWING WRAPPED UP SYSTEM
ACROSS THE UPR LAKES A COUPLE DAYS AGO IS NOW SHUNTING PRECIP WELL
TO THE SOUTH AND EAST OVER THE CNTRL GREAT LAKES ALONG PRIMARY H85
MOISTURE AXIS. THIS AGREES WELL WITH GEM-NH AND ECMWF. HIGH PRESSURE
AND DRY WEATHER DOMINATES SOUTH CNTRL CANADA INTO UPPER GREAT LAKES.
THUS DROPPED POPS ON FRIDAY AND FRIDAY NIGHT. SHOULD STAY SEASONABLY
CHILLY THOUGH WITH MID 30S NORTH AND LOWER 40S SOUTH AS NE WINDS
FLOW OFF THE ICY WATERS OF LK SUPERIOR AND THERE COULD BE MID CLOUDS
ON THE NORTHWEST SIDE OF THE FRONTAL BOUNDARY OVR THE CNTRL GREAT
LAKES.
MODEL CONSENSUS WAS USED FOR SATURDAY/EASTER SUNDAY/MONDAY. ECMWF
AND GEM-NH TRENDING WETTER FOR SATURDAY NIGHT INTO SUNDAY. PTYPE
WOULD MOSTLY BE RAIN...WITH MIX OF RAIN/SNOW POSSIBLE ON SATURDAY
NIGHT AS COOLER LOW-LEVEL AIR GRADUALLY RETREATS. GFS NOT AS EXCITED
ON THE OVERALL PCPN CHANCES. FORECAST CAME OUT WITH SLIGHT CHANCES
WITH MOSTLY CLOUDY SKIES. THIS WORKS FOR NOW AS THE CONSISTENCY IN
THE MODELS IS LESS THAN DESIRED FOR SURE. TEMPS INDICATE GRADUAL
WARMING TREND...BUT COULD SEE WARMER TEMPS THAN FORECAST IF ANY OF
THESE DAYS ENDS UP DRY WITH SOME SUNSHINE.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT)
ISSUED AT 134 AM EDT TUE APR 15 2014
ALTHOUGH AN UPPER DISTURBANCE WL BE PASSING OVER THE UPR LKS THIS
MRNG AND AIRMASS IS SUFFICIENTLY COLD FOR LK EFFECT SHSN...DRY
AIRMASS SHOWN ON THE 00Z INL AND YPL RAOBS INDICATE VFR CONDITIONS
WL PREDOMINATE. BEST CHC FOR SOME MVFR CONDITIONS WL BE AT CMX AND
IWD WITH A MORE UPSLOPE NNW FLOW...BUT INCLUDED ONLY TEMPO GROUPS IN
THE FIRST 6 HRS NOW. ARRIVAL OF SFC HI PRES RDG WL BRING VFR
CONDITIONS THIS EVNG.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 459 AM EDT TUE APR 15 2014
WINDS LESS THAN 20 KTS THROUGH TONIGHT. APPROACHING LOW PRESSURE
SYSTEM RESULTS IN INCREASING EAST TO NORTHEAST WINDS ON WEDNESDAY.
30 KTS WITH GALE GUSTS SEEMS LIKELY OVER FAR WESTERN LK SUPERIOR
WEDNESDAY AFTN INTO WEDNESDAY EVENING AS WINDS ARE ENHANCED DUE TO
CHANNELING AND TERRAIN EFFECTS. WINDS SHIFT TO THE NORTH-NORTHWEST
TO 25 KTS ON THURSDAY AS THE LOW WEAKENS WHILE MOVING TO THE EAST OF
LK SUPERIOR. WINDS STAY BLO 20 KTS FOR THE REST OF THE FORECAST
PERIOD.
&&
.HYDROLOGY...
ISSUED AT 459 AM EDT TUE APR 15 2014
GIVEN COLDER TEMPERATURES OVER THE NEXT COUPLE OF DAYS...EXPECT
SLOWER RUNOFF OF MELTING SNOW TO REDUCE THE POTENTIAL FOR ADDITIONAL
ICE JAMS. WIDESPREAD PRECIPITATION IS IN THE FORECAST FOR WEDNESDAY
THROUGH THURSDAY WITH THE POTENTIAL FOR AN ADDITIONAL INCH OF LIQUID
EQUIVALENT PRECIPITATION OVER WESTERN UPPER MICHIGAN. THIS PRECIP
ADDED TO EXISTING SNOWPACK WITH WATER EQUIVALENT OF 4-9 INCHES WILL
RESULT IN ANOTHER PERIOD OF SNOWMELT/RUNOFF AND POSSIBLE ICE JAMS ONCE
WARMER TEMPERATURES MOVE BACK INTO THE REGION NEXT WEEK.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
WINTER STORM WATCH FROM WEDNESDAY MORNING THROUGH THURSDAY
MORNING FOR MIZ001>005-009>011-084.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...JLB
LONG TERM...JLA
AVIATION...KC
MARINE...JLA
HYDROLOGY...JLA
AREA FORECAST DISCUSSION...UPDATED
NWS JACKSON MS
826 PM CDT WED APR 16 2014
.UPDATE...
QUIET NIGHT IN STORE AS HIGH PRESSURE SLOWLY BUILDS TO THE E
TONIGHT. RUC INDICATES INCREASING LOW STRATUS MOVING IN THE SE
BETWEEN 09-10Z AND UP TO THE I-20 CORRIDOR BY 12Z. EURO ALSO
INDICATES SOME LOW LEVEL CLOUDS MOVING IN. GFS INDICATES GOOD
INCREASING LOW LEVEL ISENTROPIC LIFT IN THE 295K LAYER...FURTHER
INDICATING LOW LEVEL CLOUDS MOVING IN. THUS...ONLY CHANGES TO GOING
FORECAST WERE TO INCREASE CLOUDS IN THE CENTRAL/SE BY 12Z AND
INCREASING CLOUDS FURTHER NORTH CLOSER TO 18-00Z. DUE TO SLOW NW
PROGRESSION OF LOW LEVEL MOISTURE/STRATUS...SOME DECOUPLING AND
RADIATIONAL COOLING...LEFT CURRENT LOWS FOR TONIGHT. ONLY MODIFIED
HOURLY TEMPS/DEWPOINTS ACCORDING TO CURRENT TRENDS. REST OF THE
FORECAST IS ON TRACK. /DC/
&&
.AVIATION...VFR CONDITIONS WILL PREVAIL FOR THIS EVENING AND MOST OF
THE OVERNIGHT WITH JUST SOME HIGH CLOUDS STREAMING ACROSS THE
REGION. WHAT HAS CHANGED IN THE FORECAST IS THE POTENTIAL FOR THE SE
(HBG) TO SEE SOME IFR/MVFR CEILINGS/VIS BETWEEN 11-15Z THU MORNING.
WILL ADD A MENTION OF THIS IN THE NEXT FORECAST. ANY RESTRICTIONS
SHOULD IMPROVE BY 15Z WITH VFR CONDITIONS DURING THE DAY WITH SCT
CLOUDS AROUND. /CME/
&&
.PREV DISCUSSION... /ISSUED 615 PM CDT WED APR 16 2014/
UPDATE...UPDATED FOR AVIATION DISCUSSION TO MENTION THE POTENTIAL
FOR SOME LOW CLOUDS IN THE FAR SE AROUND SUNRISE THU MORNING. /CME/
&&
PREV DISCUSSION... /ISSUED 351 PM CDT WED APR 16 2014/
SHORT TERM...TONIGHT THROUGH FRIDAY NIGHT...DRY WEATHER LOOKS TO
CONTINUE TONIGHT INTO THURSDAY AS HIGH PRESSURE TO THE NORTHEAST
CONTINUES ITS INFLUENCE OVER THE REGION. TEMPS TONIGHT WILL ONCE
AGAIN BE CHILLY...RANGING FROM THE UPPER 30S EAST TO THE LOWER 40S
WEST. WINDS WILL BE BECOMING SOUTHWESTERLY BY THURSDAY AFTERNOON
ALLOWING FOR WARMER TEMPS...MAINLY AROUND 70. A DISTURBANCE LOOKS TO
DEVELOP IN THE GULF ON THURSDAY...WHICH COULD BRING A CHANCE OF
SHOWERS ACROSS PORTIONS OF THE CWA THURSDAY NIGHT INTO FRIDAY. THE
CHANCES FOR THIS WILL DEPEND ON THE TRACK OF THIS DISTURBANCE. LATEST
MODELS INDICATE THAT THE BEST CHANCES FOR PRECIP WILL REMAIN TO OUR
SOUTH WITH THIS SYSTEM. IN ADDITION...A COLD FRONT WILL BE
APPROACHING THE CWA FRIDAY FROM THE NW. THIS FRONT LOOKS TO WEAKEN AS
IT MOVES IN...SO NOT MUCH IMPACT EXPECTED FROM THIS SYSTEM AT THIS
TIME AND WILL ONLY GO WITH SLIGHT CHANCE POPS FOR MOST LOCATIONS.
TEMPS ON FRIDAY WILL BE WARMING TO NEAR NORMAL FOR THIS TIME OF
YEAR...MAINLY IN THE MID 70S. /27/
LONG TERM...SATURDAY THROUGH TUESDAY...WE WILL CONTINUE OUR
PROGRESSIVE COMPLICATED SPLIT FLOW PATTERN THROUGH THE PERIOD. THERE
IS SOME AMPLITUDE AND TIMING DIFFERENCES ON THE MOVEMENT OF THE
NORTHERN AND SOUTHERN STREAM SHORTWAVES. EVEN THE GFS ENSEMBLES HAD
SOME DIFFERENCES IN THE MOVING AND PHASING OF SHORTWAVES IN THE
NORTHERN AND SOUTHERN STREAMS. HOWEVER ALL MODELS HAD SOME FORM OF A
COMPLICATED SPLIT FLOW PATTERN. THE GFS AND EURO GENERALLY AGREED
WITH THE GENERAL PATTERN AND MOVEMENT OF SOUTHERN STREAM ENERGY
BUT NOT MUCH AGREEMENT IN THE AMPLITUDE AND QPF WITH THE SHORTWAVES.
THIS ALSO THE CASE WITH THE NAVGEM MODEL WITH ITS OWN SOLUTION WITH
THIS UNSETTLED PATTERN. IT TRIED TO KEEP THE AREA DRY FOR THE
WEEKEND INTO EARLY NEXT WEEK. SO FORECAST CONFIDENCE IS NOT REAL
HIGH WITH THE TIMING OF THE MODELS ON THIS PROGRESSIVE PATTERN.
STARTING ON THE WEEKEND UPPER RIDGING WITH INCREASING HEIGHTS BUILDS
ACROSS THE REGION FROM THE WEST. A NEARLY PHASED SHORT WAVE WILL
APPROACH THE REGION FROM THE PLAINS FOR SUNDAY. SOUTHWEST FLOW AHEAD
OF THIS SYSTEM WILL BUILD IN MOISTURE IN FROM THE WEST FROM SATURDAY
NIGHT INTO SUNDAY. PWATS ON SUNDAY WILL INCREASE TO AROUND 1.5
INCHES. MODELS SOUNDINGS DON`T SHOW MUCH CAPPING WITH THIS SYSTEM.
AS MOISTURE TRANSPORT WILL HAVE ERODED THE DRY LAYER IN THE MIDLEVELS
FOR SUNDAY THROUGH MONDAY FOR DEEPER LAYER CONVECTION. MIDLEVEL
DRYING DOES COME BACK SOME ON TUESDAY AS WE GET SOME DRY INFLOW FROM
THE APPROACHING UPPER RIDGING FROM THE WEST. THERE WILL BE SOME
INSTABILITY WITH THIS SYSTEM AS A WARM FRONT PUSHES ACROSS THE
REGION. THE SHORTWAVE WILL TAKE ITS TIME PUSHING THROUGH THE REGION
WHICH MEANS THAT THE WARM FRONT WILL BE STATIONARY NORTH OF THE
REGION FOR SUNDAY INTO TUESDAY. THERE WILL BE ENOUGH INSTABILITY FOR
CONVECTION FOR SUNDAY THROUGH TUESDAY. THE SHORTWAVE WILL FINALLY
EXIT THE REGION BY TUESDAY NIGHT ALONG WITH THE SHOWERS AS UPPER
RIDGING BUILDS IN FROM THE WEST.
AS FAR AS POPS AND TEMPS ARE CONCERN GENERALLY STUCK CLOSE TO A BLEND
OF MEX...GMOS AND HPC GUIDANCE. /17/
&&
.PRELIMINARY POINT TEMPS/POPS...
JACKSON 40 70 55 76 / 0 4 16 14
MERIDIAN 37 69 52 74 / 0 4 20 16
VICKSBURG 41 69 54 76 / 0 4 16 14
HATTIESBURG 41 70 55 76 / 0 8 24 16
NATCHEZ 42 68 55 75 / 0 6 16 16
GREENVILLE 42 70 54 76 / 0 4 16 14
GREENWOOD 40 70 54 76 / 0 4 16 14
&&
.JAN WATCHES/WARNINGS/ADVISORIES...
MS...NONE.
LA...NONE.
AR...NONE.
&&
$$
DC/CME/27/17
AREA FORECAST DISCUSSION...UPDATED AVIATION
NWS ST LOUIS MO
1138 PM CDT Mon Apr 14 2014
.UPDATE:
Issued at 830 PM CDT Mon Apr 14 2014
Band of snow has effectively left our CWA leaving behind a region
of drizzle in its wake, now primarily confined to parts of
southwest IL. The clearing line has made it almost to
Jacksonville, IL, just passed thru Bowling Green, MO and near
Rolla, MO. At its current rate, the skies are expected to clear
for nearly the entire CWA by 06z, just in time for the start of a
total lunar eclipse. Diurnal cloudiness driving southeast from IA
is expected to further break up and dissipate over the next few
hours.
Temps continue to be on track with current forecast, supporting
continuation of Freeze Warnings with widespread mins in the mid to
upper 20s. Note that our forecast will either set or approach
current record low temps. See CLIMATE section below.
TES
&&
.SHORT TERM: (Through Late Tonight)
Issued at 324 PM CDT Mon Apr 14 2014
Main concerns deal with the band of snow currently extending from
near Pittsfield to Rolla as well as the going freeze warning. The
band has been reducing visibilities to as low as 1/2 mile with
some reports of accumulation on grassy surfaces. It is being
caused by mid level frontogenesis ahead of the 500mb trough that
will move through the area tonight. The RAP and HRRR does show the
frotogenesis weakening as it moves acrosss the CWA, but do think
that it will likely maintain itself the next few hours before it
weakens by early evening. Have extrapolated the band through CWA
through early evening, with little or no accumulation of snow
expected given the warm low level and surface temperatures.
The precipitation and clouds will clear out quick as subsidence
moves in behind the passage of the upper trough. With cold air
advection and dry dewpoints, expect temperatures to drop quickly to
near MOS temperatures. Going freeze warning looks good and plan no
changes to it.
Britt
.LONG TERM: (Tuesday through Next Monday)
Issued at 324 PM CDT Mon Apr 14 2014
(Tuesday through Thursday)
Have kept Tuesday into Thursday dry as the area will remain cut off
from any notable moisture from the Gulf and the active storm track
stays north of the area. While Tuesday night will not be as cold as
tonight, most areas will still be in the lower to mid 30s for
lows.
(Thursday Night-Next Monday)
The ECMWF and GFS are now similar with the amplitude and timing of
the mid level trough and attendant cold front that will move across
the area on Friday. Will continue with the chance of showers on
Thursday night and Friday before subsidence works in behind the
trough keeping Friday night and Saturday dry. Then confidence
begins to wane late in the weekend as they both develop QPF over the
area. The GFS is placing more emphasis on an northern stream upper
over the Upper Midwest while ECMWF is placing it`s emphasis on a
shortwave coming out of the southwest CONUS. Either way, will
continue the chance of showers we have going Saturday night into
Sunday night. Temperatures during the period look to be near or
slightly below normal.
Britt
&&
.AVIATION: (For the 06z TAFs through 06z Tuesday Night)
Issued at 1136 PM CDT Mon Apr 14 2014
Skies have cleared out of taf sites, so clear skies and northwest
winds to persist overnight. Will see some diurnal cu develop by
midday on Tuesday with winds gradually backing to the southwest
then south as surface ridge moves to the east.
Specifics for KSTL:
Skies have cleared out of taf sites, so clear skies and northwest
winds to persist overnight. Will see some diurnal cu develop by
18z Tuesday with winds gradually backing to the southwest then
south by 01z Wednesday as surface ridge moves to the east.
Byrd
&&
.CLIMATE:
RECORD LOWS FOR 4/15:
STL - 27 IN 1928
COU - 25 IN 1928
UIN - 24 IN 1928
FAM - 24 IN 1928
&&
.LSX WATCHES/WARNINGS/ADVISORIES:
MO...FREEZE WARNING until 9 AM CDT Tuesday FOR Audrain MO-Boone MO-
Callaway MO-Cole MO-Crawford MO-Franklin MO-Gasconade MO-
Iron MO-Jefferson MO-Knox MO-Lewis MO-Lincoln MO-Madison MO-
Marion MO-Moniteau MO-Monroe MO-Montgomery MO-Osage MO-Pike
MO-Ralls MO-Reynolds MO-Shelby MO-St. Charles MO-St.
Francois MO-St. Louis City MO-St. Louis MO-Ste. Genevieve
MO-Warren MO-Washington MO.
IL...FREEZE WARNING until 9 AM CDT Tuesday FOR Adams IL-Bond IL-Brown
IL-Calhoun IL-Clinton IL-Fayette IL-Greene IL-Jersey IL-
Macoupin IL-Madison IL-Marion IL-Monroe IL-Montgomery IL-
Pike IL-Randolph IL-St. Clair IL-Washington IL.
&&
$$
WFO LSX
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
404 AM EDT TUE APR 15 2014
.SYNOPSIS...
A STRONG COLD FRONT WILL BRING A PERIOD OF HEAVY RAIN TO THE AREA
TODAY. MUCH COLDER AIR WILL FOLLOW THIS FRONT WITH A BRIEF CHANGE
TO SNOW AND SLEET BEFORE THE PRECIPITATION ENDS EARLY THIS
EVENING. WEDNESDAY WILL BE UNSEASONABLY COLD...WITH MILDER WEATHER
RETURNING BY LATE THIS WEEK.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
WARM TEMPERATURES OVER THE LAKE PLAIN WERE ENOUGH INSTABILITY TO
GET A LINE OF SHOWERS GOING WITH BRIEF HEAVY RAINS AND GUSTY WINDS
TO 40 MPH. NO CLOUD TO GROUND LIGHTNING STRIKES WERE PICKED UP BUT
SOME IN-CLOUD LIGHTNING WAS REPORTED NORTH OF PENN YAN. TEMPS
DROP ABOUT 10 DEGREES AS THE SHOWERS MOVE THROUGH BUT THEN THIS
SHOULD LEVEL OUT. THE LINE OF SHOWERS IS CONTINUING TO PROGRESS
EAST THROUGH THE CENTRAL PORTION OF OUR FORECAST AREA. BEHIND THIS
LINE TO THE WEST A CHANCE OF LIGHT SHOWERS IS POSSIBLE INTO THE
OVERNIGHT. TO THE EAST THE LINE IS EXPECTED TO STALL AND WEAKEN AS
THE SUNSETS. SCATTERED SHOWERS WILL REMAIN POSSIBLE PAST MIDNIGHT.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM WEDNESDAY/...
A STRONG COLD FRONT WILL TRACK ACROSS THE AREA THROUGH THIS PERIOD
BRINGING A PERIOD OF HEAVY RAIN TO MUCH OF THE AREA ALONG WITH
RAPIDLY FALLING TEMPERATURES AND A LIKELY CHANGE-OVER TO SNOW AND
SLEET. DETAILS ARE GIVEN BELOW.
A BAND OF SCATTERED SHOWERS MOVING ACROSS THE AREA THIS EVENING
IS STILL WELL AHEAD OF THE COLD FRONT WHICH IS BACK TO THE WEST
AROUND DTW. THESE SHOWERS WILL TEND TO LIFT NORTHEAST AND WEAKEN
THROUGH THIS EVENING BUT THERE STILL APPEARS TO BE A GOOD CHANCE
FOR A ROUND OF SHOWERS THIS EVENING AS THIS SYSTEM MOVES ACROSS
THE AREA. LATEST RAP MODEL SOUNDINGS HARDLY INDICATING ANY CAPE
OVER THE AREA THIS EVENING AND HAVE LEFT OUT ANY THUNDER MENTION.
EXPECT A LULL IN THE ACTIVITY OVER NIGHT IN THE WAKE OF THIS
SYSTEM... BEFORE RAIN BEGINS TO INCREASE WITH THE APPROACH OF THE
COLD FRONT TOWARD DAYBREAK. IT WILL BE A VERY MILD NIGHT WITH
SOUTHERLY BREEZES AND LOW TEMPERATURES MOSTLY 55 TO 60... MORE
SEASONABLE FOR JUNE THAN MID-APRIL.
A STRONG COLD FRONT WILL TRACK SLOWLY EAST ACROSS THE CWA ON
TUESDAY. THIS FRONT WILL BE ACCOMPANIED BY STRONG RIGHT-REAR QUAD
UPPER DYNAMICS AND A 50 KT LOW-LEVEL SOUTHERLY JET. INSTABILITY
ALONG AND AHEAD OF THE FRONT WILL BE MINIMAL BUT CAN`T RULE OUT A
FEW RUMBLES OF THUNDER RIGHT WITH THE FRONTAL PASSAGE DURING
MIDDAY TUESDAY. AT THIS TIME WE ARE EXPECTING SHOWERS TO INCREASE AHEAD
OF THE FRONT EARLY TUESDAY... THEN A BAND OF MODERATE TO HEAVY
RAIN WILL LIKELY ACCOMPANY AND FOLLOW THE FRONTAL PASSAGE... LATE
TUESDAY MORNING OVER THE FINGER LAKES... AROUND NOON ALONG THE
I-81 CORRIDOR... AND EARLY AFTERNOON OVER THE WESTERN CATSKILLS.
SOME CONCERN THAT ANY BAND OF HEAVY RAIN THAT DEVELOPS ALONG THE
FRONT COULD BE HEAVY ENOUGH TO CAUSE SOME MINOR FLOODING ISSUES IF
HEAVY RAIN FALLS DURING A SHORT PERIOD. TOTAL RAINFALL WITH THE
SYSTEM IS EXPECTED TO BE IN THE 1 TO 1.5 INCH RANGE. HAVE HELD OFF
ON ANY WATCHES AT THIS POINT... BUT A WATCH MAY NEED CONSIDERATION
ONCE TIMING AN LOCATION OF ANY HEAVY RAIN BANDS BECOMES MORE
CERTAIN.
SOUTHWEST WINDS WILL INCREASE TONIGHT AS THE FRONT APPROACHES.
SOME GUSTS TO 30 OR 40 MPH WILL BE POSSIBLE OVER HIGHER TERRAIN
LATER TONIGHT WITH LIGHTER WINDS AT LOWER ELEVATIONS. NORTHWEST
WINDS WILL BE STRONG AND GUSTY BEHIND THE FRONT LATE TUESDAY INTO
TUESDAY NIGHT. SOME GUSTS OF 30 TO 40 MPH ARE POSSIBLE.
THIS WILL BE AN ANAFRONT WITH SEVERAL HOURS OF PRECIPITATION
LINGERING BEHIND THE FRONT. COLD AIR MOVES IN QUICKLY BEHIND THE
FRONT WITH RAIN CHANGING TO SLEET OR A MIX OF SLEET AND SNOW OVER
THE FINGER LAKES BY LATE MORNING... AND ALONG THE I-81 CORRIDOR BY
MID TO LATE AFTERNOON. MODELS ARE IN EXCELLENT AGREEMENT WITH THIS
SCENARIO AND INDICATE THE POTENTIAL FOR A WIDESPREAD 1 TO 3 INCHES
OF SNOW AND SLEET BY EARLY EVENING TUESDAY FOR MOST OF THE AREA.
STEADIER SNOW WILL END ACROSS THE AREA EARLY TUESDAY EVENING BUT
850 MB TEMPERATURES FALL TO AROUND -15 DEGREES C. DESPITE VERY DRY
AIR EXPECT THAT THIS SCEANRIO WILL SUPPORT A LITTLE BIT OF LAKE
EFFECT SNOW OVER CENTRAL NY TUESDAY EVENING. ANY ADDITIONAL
ACCUMULATIONS SHOULD BE LIGHT.
&&
.LONG TERM /WEDNESDAY NIGHT THROUGH MONDAY/...
QUIET WX IN THE MED RNG WITH HIGH PRES BUILDING INTO THE RGN ON
WED. AFTER SOME MRNG LAKE CLDS...MOSTLY SUNNY SKIES WILL PREVAIL.
FAIR AND DRY WEATHER PERSISTS INTO FRIDAY AS THE SFC HIGH SLIDES
OFF THE CST. WE COULD SEE CLDS RETURN IN THE SELY FLOW LATER FRI
NGT INTO SAT. THIS WEEKEND`S FCST IS RATHER UNCERTAIN...HINGING ON
THE INTERACTION BETWEEN NRN AND SRN STREAM S/WV`S. JUST WENT WITH
SLGT CHC/LOW CHC POPS FOR THIS PD.
TEMPS WILL BE WELL BLO NORMAL ON WED...A MODERATING TREND
AFTERWARDS AND WITH TEMPS RISING TO NEAR OR SLIGHTLY ABV SEASONAL
NORMS.
&&
.AVIATION /08Z TUESDAY THROUGH SATURDAY/...
SCATTERED SHRA WERE DEVELOPING IN ADVANCE OF THE SHARP COLD FRONT
THAT WILL MOVE ACRS CENTRAL NY AND NORTHEAST PA BETWEEN 11Z AND
19Z FROM NW TO SE. MOST OF THESE SHRA WILL BE VFR WITH PATCHY
AREAS OF MVFR IN THE HEAVIEST SHRA. THE COLD FRONT W/ A SHARP WIND
SHIFT FROM S TO NW REACHES SYR-PEO BY 12Z TO 13Z...UCA-ELM BY
14Z...KITH BY 15Z...KBGM BY 16Z...AND KAVP BY 19Z. FOR A FEW HOURS
AFTER FRONTAL PASSAGE CIGS AND VSBYS WILL DROP TO IFR WITH RA AND
BR...THEN THE PRECIP WILL BECOME A MIX OF SNOW/PL AND RAIN WITH A
VERY SHARP LOW-LEVEL INVERSION. THERE CUD BE LOW-LEVEL WIND SHEAR
AT THE POINT IN THE INVERSION LAYER WHICH WILL BE FAIRLY LOW. THUS
LLWS REMAINS IN ALL TAFS TO ACCOUNT FOR A FEW HOUR WINDOW THIS
AFTERNOON. AS THE COLD AIR LAYER DEEPENS VERTICALLY THE SHEAR WILL
LESSEN TWD EVE. IN CONJUNCTION WITH THIS DEEPENING COLD LAYER...THE
PRECIP WILL TURN TO ALL SNOW. I EXPECT MAINLY IFR CIG AND VSBY IN
SNOW AND BR FOR A FEW HOURS. THEN CONDITIONS WILL IMPROVE TO
MAINLY MVFR TO VFR CIG AND VSBY IN -SHSN MOSTLY AFTER 00Z.
WINDS WILL BE MAINLY S-SE ARND 10 KNOTS WITH OCCASIONAL GUST TO 20
KNOTS...THEN THE WINDS WILL SHIFT TO THE NW AFTER FROPA AN AVERAGE
10 TO 20 KNOTS GUSTS TO 25 KTS OR MORE. WINDS CUD GET EVEN
STRONGER TWD 00Z.
OUTLOOK...
TUE NGT...SCT MVFR IN -SHSN CNTRL NY.
WED-THU-FRI...VFR.
FRI NGT/SAT...MVFR CIGS PSBL IN SELY FLOW OVER NE PA AND SRN NY.
&&
.FIRE WEATHER...
NO FIRE WEATHER CONCERNS THROUGH WEDNESDAY.
&&
.HYDROLOGY...
AT THIS TIME LATEST TOTAL PRECIPITATION FORECASTS ARE FOR 1.5
INCHES TO 1.75 INCHES MAINLY EAST OF THE I-81 CORRIDOR AND LESS
THAN 1.5 INCHES TO THE WEST. THE COMPLICATING FACTOR IS THAT THE
TAIL OF END OF THIS PRECIPITATION LIKELY WILL BE IN THE FORM OF
SNOW. OF CONCERN IS THAT A LOT OF THIS RAIN COULD FALL IN A FAIRLY
SHORT PERIOD OF TIME INCREASING THE THREAT FOR SOME FLOOD ISSUES
ON SMALLER STREAMS...AND ESPECIALLY URBAN AND POOR DRAINAGE AREAS.
AS OF EARLY THIS MORNING...FLOOD WATCHES AND WARNINGS REMAIN IN
EFFECT FOR ONEIDA COUNTY WHERE WE ARE WATCHING THE WEST CANADA
CREEK CLOSELY. THE WEST CANADA CREEK WAS AT 1226.26 FEET AS OF 245
AM EDT AND STILL RISING AT A STEADY CLIP. A FLOOD WARNING IS IN
EFFECT FOR THIS CREEK AS PER NWS ALY. LATEST NERFC FORECAST
GUIDANCE BRINGS IT 1228 FEET WHICH IS AT THE MODERATE FLOOD LEVEL.
IN ADDTN THERE WILL CONTINUE TO BE THE POTENTIAL FOR SMALLER
STREAMS IN ONEIDA COUNTY TO SPILL THEIR BANKS LATER TODAY AS AN
ADDITIONAL 1.5 INCHES OF RAIN OR SO WILL BE POSSIBLE. CONCERNED
ABT THE SRLY UPSLOPE FLOW THAT COULD ENHANCE RAINFALL AS WELL. FOR
NOW THE ONEIDA CREEK AT ONEIDA IS NOT EXPECTED TO FLOOD BUT IF
LOCALLY HEAVIER RAIN (MORE THAN 2 INCHES) FALLS IN THAT
WATERSHED...FLOODING WILL BE POSSIBLE. THE SAQUOIT CREEK AND
ORISKANY CREEKS ALSO WILL HAVE THE POTENTIAL TO FLOOD IF ENOUGH
RAIN FALLS IN THESE SMALLER WATERSHEDS. FLASH FLOOD GUIDANCE FOR
ONEIDA COUNTY IS BETWEEN 2.0 AND 2.5 INCHES IN A 3 TO 6 HOUR
PERIOD. THIS COULD BE A LITTLE HARD TO COME BY...EXCEPT LOCALLY.
SO A FLOOD WATCH WILL CONT FOR ONEIDA COUNTY TO COVER THE ELEVATED
POTENTIAL FOR FLOOD ISSUES UP THERE.
FARTHER SOUTH THERE IS MORE UNCERTAINTY. CURRENT RIVER FORECASTS
SHOW NO RIVER FLOODING...EVEN IN THE HEADWATERS. HEADWATER FORECAST
GUIDANCE FOR MOST AREAS IS RUNNING AOA 2 INCHES IN 3 TO 6 HOURS
EXCEPT AT SHERBURNE WHERE IT IS CLOSER TO 1 INCHES FOR MINOR
FLOODING AND 1.5 INCHES FOR MODERATE FLOODING. THIS POINT WILL
BEARS WATCHING AND IS AN OUTLIER AMONG ALL OTHER HEADWATER FORECAST
POINTS. A FEW HEADWATER POINTS CUD SEE MINOR FLOODING WITH 1.5
INCHES OF RAIN IN 6 HOURS BUT MODERATE FLOODING THRESHOLDS ARE
OVER 2 INCHES. SO AFTER COLLABORATION WITH NEIGHBORING NWS
OFFICES DECIDED NOT TO ISSUE AN FFA JUST YET. IF A BAND OF HEAVY
DEVELOPS LATER THIS MORNING AND HAS 1 INCH PER HOUR OR 2 INCH PER
3 HOUR RAINFALL RATES THE DAY SHIFT CAN ISSUE A SHORT FUSED FLASH
FLOOD WATCH AS NECESSARY. WE WILL BE ISSUING AN SPS TO COVER THE
POTENTIAL FOR SOME FLOODING OUTSIDE OUR FLOOD WATCH AREA AND HIT
THE URBAN...POOR DRAINAGE AND LOW-LYING AREAS THE HARDEST.
&&
.BGM WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NY...FLOOD WATCH FROM 8 AM EDT THIS MORNING THROUGH THIS EVENING
FOR NYZ009-037.
&&
$$
SYNOPSIS...DJN
NEAR TERM...BMW
SHORT TERM...MSE
LONG TERM...
AVIATION...DJN
FIRE WEATHER...DJN
HYDROLOGY...DJN
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
200 AM EDT TUE APR 15 2014
.SYNOPSIS...
VERY MILD WEATHER WILL CONTINUE TONIGHT WITH SCATTERED SHOWERS AND
TEMPERATURES ONLY FALLING INTO THE MID TO UPPER 50S. A STRONG COLD
FRONT WILL BRING A PERIOD OF HEAVY RAIN TO THE AREA ON TUESDAY...
FOLLOWED BY MUCH COLDER AIR AND A BRIEF CHANGE TO SNOW AND SLEET
BEFORE THE PRECIPITATION ENDS EARLY TUESDAY EVENING. WEDNESDAY
WILL BE UNSEASONABLY COLD... THE MILDER WEATHER WILL RETURN BY
LATE THIS WEEK.
&&
.NEAR TERM /THROUGH TODAY/...
WARM TEMPERATURES OVER THE LAKE PLAIN WERE ENOUGH INSTABILITY TO
GET A LINE OF SHOWERS GOING WITH BRIEF HEAVY RAINS AND GUSTY WINDS
TO 40 MPH. NO CLOUD TO GROUND LIGHTNING STRIKES WERE PICKED UP BUT
SOME IN-CLOUD LIGHTNING WAS REPORTED NORTH OF PENN YAN. TEMPS
DROP ABOUT 10 DEGREES AS THE SHOWERS MOVE THROUGH BUT THEN THIS
SHOULD LEVEL OUT. THE LINE OF SHOWERS IS CONTINUING TO PROGRESS
EAST THROUGH THE CENTRAL PORTION OF OUR FORECAST AREA. BEHIND THIS
LINE TO THE WEST A CHANCE OF LIGHT SHOWERS IS POSSIBLE INTO THE
OVERNIGHT. TO THE EAST THE LINE IS EXPECTED TO STALL AND WEAKEN AS
THE SUNSETS. SCATTERED SHOWERS WILL REMAIN POSSIBLE PAST MIDNIGHT.
&&
.SHORT TERM /TONIGHT THROUGH 6 PM WEDNESDAY/...
A STRONG COLD FRONT WILL TRACK ACROSS THE AREA THROUGH THIS PERIOD
BRINGING A PERIOD OF HEAVY RAIN TO MUCH OF THE AREA ALONG WITH
RAPIDLY FALLING TEMPERATURES AND A LIKELY CHANGE-OVER TO SNOW AND
SLEET. DETAILS ARE GIVEN BELOW.
A BAND OF SCATTERED SHOWERS MOVING ACROSS THE AREA THIS EVENING
IS STILL WELL AHEAD OF THE COLD FRONT WHICH IS BACK TO THE WEST
AROUND DTW. THESE SHOWERS WILL TEND TO LIFT NORTHEAST AND WEAKEN
THROUGH THIS EVENING BUT THERE STILL APPEARS TO BE A GOOD CHANCE
FOR A ROUND OF SHOWERS THIS EVENING AS THIS SYSTEM MOVES ACROSS
THE AREA. LATEST RAP MODEL SOUNDINGS HARDLY INDICATING ANY CAPE
OVER THE AREA THIS EVENING AND HAVE LEFT OUT ANY THUNDER MENTION.
EXPECT A LULL IN THE ACTIVITY OVER NIGHT IN THE WAKE OF THIS
SYSTEM... BEFORE RAIN BEGINS TO INCREASE WITH THE APPROACH OF THE
COLD FRONT TOWARD DAYBREAK. IT WILL BE A VERY MILD NIGHT WITH
SOUTHERLY BREEZES AND LOW TEMPERATURES MOSTLY 55 TO 60... MORE
SEASONABLE FOR JUNE THAN MID-APRIL.
A STRONG COLD FRONT WILL TRACK SLOWLY EAST ACROSS THE CWA ON
TUESDAY. THIS FRONT WILL BE ACCOMPANIED BY STRONG RIGHT-REAR QUAD
UPPER DYNAMICS AND A 50 KT LOW-LEVEL SOUTHERLY JET. INSTABILITY
ALONG AND AHEAD OF THE FRONT WILL BE MINIMAL BUT CAN`T RULE OUT A
FEW RUMBLES OF THUNDER RIGHT WITH THE FRONTAL PASSAGE DURING
MIDDAY TUESDAY. AT THIS TIME WE ARE EXPECTING SHOWERS TO INCREASE AHEAD
OF THE FRONT EARLY TUESDAY... THEN A BAND OF MODERATE TO HEAVY
RAIN WILL LIKELY ACCOMPANY AND FOLLOW THE FRONTAL PASSAGE... LATE
TUESDAY MORNING OVER THE FINGER LAKES... AROUND NOON ALONG THE
I-81 CORRIDOR... AND EARLY AFTERNOON OVER THE WESTERN CATSKILLS.
SOME CONCERN THAT ANY BAND OF HEAVY RAIN THAT DEVELOPS ALONG THE
FRONT COULD BE HEAVY ENOUGH TO CAUSE SOME MINOR FLOODING ISSUES IF
HEAVY RAIN FALLS DURING A SHORT PERIOD. TOTAL RAINFALL WITH THE
SYSTEM IS EXPECTED TO BE IN THE 1 TO 1.5 INCH RANGE. HAVE HELD OFF
ON ANY WATCHES AT THIS POINT... BUT A WATCH MAY NEED CONSIDERATION
ONCE TIMING AN LOCATION OF ANY HEAVY RAIN BANDS BECOMES MORE
CERTAIN.
SOUTHWEST WINDS WILL INCREASE TONIGHT AS THE FRONT APPROACHES.
SOME GUSTS TO 30 OR 40 MPH WILL BE POSSIBLE OVER HIGHER TERRAIN
LATER TONIGHT WITH LIGHTER WINDS AT LOWER ELEVATIONS. NORTHWEST
WINDS WILL BE STRONG AND GUSTY BEHIND THE FRONT LATE TUESDAY INTO
TUESDAY NIGHT. SOME GUSTS OF 30 TO 40 MPH ARE POSSIBLE.
THIS WILL BE AN ANAFRONT WITH SEVERAL HOURS OF PRECIPITATION
LINGERING BEHIND THE FRONT. COLD AIR MOVES IN QUICKLY BEHIND THE
FRONT WITH RAIN CHANGING TO SLEET OR A MIX OF SLEET AND SNOW OVER
THE FINGER LAKES BY LATE MORNING... AND ALONG THE I-81 CORRIDOR BY
MID TO LATE AFTERNOON. MODELS ARE IN EXCELLENT AGREEMENT WITH THIS
SCENARIO AND INDICATE THE POTENTIAL FOR A WIDESPREAD 1 TO 3 INCHES
OF SNOW AND SLEET BY EARLY EVENING TUESDAY FOR MOST OF THE AREA.
STEADIER SNOW WILL END ACROSS THE AREA EARLY TUESDAY EVENING BUT
850 MB TEMPERATURES FALL TO AROUND -15 DEGREES C. DESPITE VERY DRY
AIR EXPECT THAT THIS SCEANRIO WILL SUPPORT A LITTLE BIT OF LAKE
EFFECT SNOW OVER CENTRAL NY TUESDAY EVENING. ANY ADDITIONAL
ACCUMULATIONS SHOULD BE LIGHT.
&&
.LONG TERM /WEDNESDAY NIGHT THROUGH MONDAY/...
QUIET WX IN THE MED RNG WITH HIGH PRES BUILDING INTO THE RGN ON
WED. AFTER SOME MRNG LAKE CLDS...MOSTLY SUNNY SKIES WILL PREVAIL.
FAIR AND DRY WEATHER PERSISTS INTO FRIDAY AS THE SFC HIGH SLIDES
OFF THE CST. WE COULD SEE CLDS RETURN IN THE SELY FLOW LATER FRI
NGT INTO SAT. THIS WEEKEND`S FCST IS RATHER UNCERTAIN...HINGING ON
THE INTERACTION BETWEEN NRN AND SRN STREAM S/WV`S. JUST WENT WITH
SLGT CHC/LOW CHC POPS FOR THIS PD.
TEMPS WILL BE WELL BLO NORMAL ON WED...A MODERATING TREND
AFTERWARDS AND WITH TEMPS RISING TO NEAR OR SLIGHTLY ABV SEASONAL
NORMS.
&&
.AVIATION /06Z TUESDAY THROUGH SATURDAY/...
SCATTERED SHRA WERE DEVELOPING IN ADVANCE OF THE SHARP COLD FRONT
THAT WILL MOVE ACRS CENTRAL NY AND NORTHEAST PA BETWEEN 11Z AND
19Z FROM NW TO SE. MOST OF THESE SHRA WILL BE VFR WITH PATCHY
AREAS OF MVFR IN THE HEAVIEST SHRA. THE COLD FRONT W/ A SHARP WIND
SHIFT FROM S TO NW REACHES SYR-PEO BY 12Z TO 13Z...UCA-ELM BY
14Z...KITH BY 15Z...KBGM BY 16Z...AND KAVP BY 19Z. FOR A FEW HOURS
AFTER FRONTAL PASSAGE CIGS AND VSBYS WILL DROP TO IFR WITH RA AND
BR...THEN THE PRECIP WILL BECOME A MIX OF SNOW/PL AND RAIN WITH A
VERY SHARP LOW-LEVEL INVERSION. THERE CUD BE LOW-LEVEL WIND SHEAR
AT THE POINT IN THE INVERSION LAYER WHICH WILL BE FAIRLY LOW. THUS
LLWS REMAINS IN ALL TAFS TO ACCOUNT FOR A FEW HOUR WINDOW THIS
AFTERNOON. AS THE COLD AIR LAYER DEEPENS VERTICALLY THE SHEAR WILL
LESSEN TWD EVE. IN CONJUNCTION WITH THIS DEEPENING COLD LAYER...THE
PRECIP WILL TURN TO ALL SNOW. I EXPECT MAINLY IFR CIG AND VSBY IN
SNOW AND BR FOR A FEW HOURS. THEN CONDITIONS WILL IMPROVE TO
MAINLY MVFR TO VFR CIG AND VSBY IN -SHSN MOSTLY AFTER 00Z.
WINDS WILL BE MAINLY S-SE ARND 10 KNOTS WITH OCCASIONAL GUST TO 20
KNOTS...THEN THE WINDS WILL SHIFT TO THE NW AFTER FROPA AN AVERAGE
10 TO 20 KNOTS GUSTS TO 25 KTS OR MORE. WINDS CUD GET EVEN
STRONGER TWD 00Z.
OUTLOOK...
TUE NGT...SCT MVFR IN -SHSN CNTRL NY.
WED-THU-FRI...VFR.
FRI NGT/SAT...MVFR CIGS PSBL IN SELY FLOW OVER NE PA AND SRN NY.
&&
.FIRE WEATHER...
NO FIRE WEATHER CONCERNS THROUGH WEDNESDAY.
&&
.BGM WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NY...FLOOD WATCH FROM 8 AM EDT THIS MORNING THROUGH THIS EVENING
FOR NYZ009-037.
&&
$$
SYNOPSIS...MSE
NEAR TERM...BMW
SHORT TERM...MSE
LONG TERM...
AVIATION...DJN
FIRE WEATHER...
AREA FORECAST DISCUSSION
NWS RALEIGH NC
1000 PM EDT WED APR 16 2014
.SYNOPSIS... UNSEASONABLY STRONG...POLAR HIGH PRESSURE WILL BUILD
EAST ACROSS THE MIDDLE ATLANTIC AND NORTHEAST STATES THROUGH
THURSDAY. A LOW PRESSURE SYSTEM IS THEN EXPECTED TO TRACK NEAR THE
SOUTHEAST COAST OVER THE WEEKEND.
&&
.NEAR TERM /THROUGH THURSDAY/...
AS OF 1000 PM WEDNESDAY...
PRESSURE READINGS CONTINUE TO RISE ACROSS CENTRAL NC THIS EVENING AS
A STRONG 1036MB SURFACE HIGH OVER NEW ENGLAND REACHES DOWN THE EAST
COAST. THE MAIN STORY FOR THE OVERNIGHT PERIOD IS THE POTENTIAL FOR
FREEZE AND FROST. WINDS HAVE DECOUPLED IN SOME SPOTS...BUT THE
BUILDING SURFACE RIDGE IS KEEPING A LIGHT WIND STIRRING OVER MOST OF
THE AREA. SHOULD SEE MORE AREAS DECOUPLE BY AFTER
MIDNIGHT...ESPECIALLY ACROSS WESTERN AREAS. HOWEVER...THE PRESSURE
GRADIENT IS FORECAST TO TIGHTEN A BIT OVER EASTERN NC BY 09Z IN
RESPONSE TO A WESTWARD MIGRATING INVERTED TROUGH OFFSHORE...AND THE
RATE AT WHICH TEMPS FALL OVER THE COASTAL PLAIN WILL SLOW AS THE
RIDGE AXIS SETTLES TOWARD THE PIEDMONT. COULD ISSUE A FROST
ADVISORY FOR THE COASTAL PLAIN...BUT RAP SOUNDINGS SHOW THE BOUNDARY
LAYER STAYING AT LEAST PARTIALLY MIXED THROUGHOUT THE NIGHT...AND
THE FROST SHOULD REMAIN PATCHY IN NATURE. THE FREEZE WARNING WILL
CONTINUE AS FORECAST. IR SATELLITE IMAGERY SHOWS QUITE A BIT OF
STRATO CU OFFSHORE...WHICH WILL BEGIN TO SPREAD INLAND LATE TONIGHT
AND TOWARD THE I-95 CORRIDOR DURING THE MID-MORNING HOURS ON
THURSDAY. -SMITH
THURSDAY...CIRCULATION AROUND THE LOW LEVEL RIDGE WILL RESULT IN A
LONG NE FETCH OFF THE ATLANTIC INTO EASTERN NC. THIS FLOW WILL
TRANSPORT A SHALLOW THIN LAYER OF MOISTURE INTO THE COASTAL
PLAIN...RESULTING IN A SCATTERED TO BRIEFLY BROKEN LAYER OF STRATOCU
OVER THE COASTAL PLAIN LATER THURSDAY MORNING INTO THURSDAY
AFTERNOON. LAYER TOO SHALLOW TO SUPPORT ANYTHING MORE THAN SPRINKLES
IF EVEN THAT.
TEMPS WILL REMAIN WELL BELOW NORMAL FOR MID APRIL THOUGH SOME
RECOVERY COMPARED TO TODAY ANTICIPATED. AFTERNOON THICKNESSES
PROJECTED TO BE ABOUT 20M WARMT THAN THIS AFTERNOON WHICH SUGGEST
AFTERNOON TEMPS THURSDAY ABOUT 5 DEGREES WARMER THAN THIS AFTERNOON.
THIS IS MORE SIMILAR TO THE COOLER GFS MOS GUIDANCE. MAX TEMPS UPPER
50S TO LOWER 60S.
&&
.SHORT TERM /THURSDAY NIGHT AND FRIDAY /...
AS OF 330 PM WEDNESDAY...
THURSDAY NIGHT AND FRIDAY....SFC RIDGE AXIS WILL LIKELY MAINTAIN ITS
INFLUENCE OVER THE PIEDMONT OF CENTRAL NC THROUGH THIS PERIOD AS
PARENT HIGH BECOMES ANCHORED OVER NORTHERN NEW ENGLAND/CANADIAN
MARITIME DUE TO CONFLUENT FLOW ALOFT. WHILE THE AIR MASS UNDERNEATH
THIS RIDGE WILL GRADUALLY MODIFY...PRESENCE OF DRY AIR UNDER THIS
WEATHER SYSTEM WILL MAINTAIN A BASICALLY CLOUD FREE ATMOSPHERE IN
THE LOWEST 10K FEET. MEANWHILE...A S/W IS PROJECTED TO MOVE EAST-SE
ACROSS THE CENTRAL NC PLAINS AND INTO THE TN VALLEY WHERE IT IS
PROJECTED TO BEGIN TO INTERACT WITH A SYSTEM LIFTING E-NE ACROSS THE
NORTHERN GULF. UPPER LEVEL FLOW OVER THE CAROLINAS WILL BACK IN
RESPONSE TO THE APPROACH OF THESE SYSTEMS...TRANSPORTING HIGH LEVEL
MOISTURE INTO OUR REGION. THIS SHOULD RESULT IN AN INCREASING VEIL
OF HIGH CLOUDS THURSDAY NIGHT INTO FRIDAY. THE THICKNESS OF THESE
HIGH CLOUDS WILL PLAY A ROLE IN WHETHER SCATTERED FROST WILL DEVELOP
OVER THE PIEDMONT THURSDAY NIGHT/EARLY FRIDAY. IN ADDITION...LOW
LEVEL ELY FLOW WILL ADVECT MOISTURE OFF THE ATLANTIC INTO THE
COASTAL PLAIN BY FRIDAY MORNING. MIN TEMPS MID 30S WEST TO UPPER
30S/AROUND 40 EAST.
SHOULD SEE AT A MINIMUM A MIXTURE OF SUN AND CLOUDS FRIDAY WITH THE
CHARACTER OF THE SKY BECOMING MOSTLY CLOUDY OR OVERCAST BY FRIDAY
AFTERNOON. ISENTROPIC UPGLIDE DOES NOT APPEAR STRONG ENOUGH TO
SUPPORT PRECIP FRIDAY AFTERNOON...ASIDE FROM A STRAY SHOWER ACROSS
THE FAR SE.
AIR MASS WILL CONTINUE TO GRADUALLY MODIFY BUT AFTERNOON TEMPS WILL
REMAIN WELL BELOW NORMAL. MAX TEMPS 60-65.
&&
.LONG TERM /FRIDAY NIGHT THROUGH WEDNESDAY/...
AS OF 3 PM WEDNESDAY...
FRIDAY NIGHT THROUGH SUNDAY NIGHT: THE WEEKEND FORECAST CONTINUES TO
HAVE SOME UNCERTAINTY WITH REGARD TO THE EVOLUTION OF A POSSIBLE
CLOSED LOW LINGERING ACROSS THE SOUTHEASTERN U.S/OFFSHORE. WHILE THE
NORTHERN STREAM ENERGY IS PROGRESSIVE AND PUSHES EASTWARD FRIDAY
NIGHT INTO SATURDAY. IN ADVANCE OF THE NORTHERN STREAM TROUGH BOTH
THE 12Z GFS AND ECMWF PULLS MOISTURE NORTHWARD... AND PRODUCED SOME
LIGHT RAIN ACROSS OUR FAR SOUTHEAST/EAST ON FRIDAY NIGHT INTO EARLY
SATURDAY MORNING... WITH THE BULK OF THE PRECIP EXPECTED TO BE TO
OUR EAST AND SOUTH. HOWEVER... MODEL GUIDANCES IS STRUGGLING WITH
WHAT WILL HAPPEN WITH THE LINGERING SOUTHERN STEAM ENERGY THAT
POSSIBLY CLOSES OFF INTO A CLOSED LOW AND LINGERS NEAR FL AND OFF
THE SOUTHEAST U.S. COAST. THE 12Z ECMWF HAS COME A MORE IN THE LINE
WITH THE 12Z GFS IN SHOWING LINGERING MID LEVEL ENERGY SLOWLY
SHIFTING EASTWARD AND FAR ENOUGH AWAY FROM THE COAST TO KEEP US DRY
SATURDAY AFTERNOON THROUGH THE REST OF THE WEEKEND. HOWEVER...
GUIDANCES HAS SHOWN POOR RUN TO RUN CONTINUITY. THUS... CONFIDENCE
IS NOT HIGH THAT LATE SATURDAY INTO SUNDAY THAT WE WILL BE
COMPLETELY DRY AT THIS TIME ACROSS OUR ENTIRE AREA (IF PRECIP
LINGER... LOCATIONS ACROSS THE EAST/SOUTHEAST WOULD SEE THE BEST
CHANCE/MOST). FOR NOW WILL GO WITH A DRY FORECAST AS MENTIONED ABOVE
FROM SATURDAY AFTERNOON ONWARD.
WITH SURFACE HIGH PRESSURE BUILDING INTO THE AREA FROM THE NORTH AND
A COOL EAST TO NORTHEASTERLY LOW LEVEL FLOW EXPECT HIGH TEMPS WILL
REMAIN SLIGHTLY BELOW NORMAL WITH AT LEAST SOME CLOUD COVER (MORE
EAST VS WEST). THUS... WILL GO WITH HIGH TEMPS THIS WEEKEND IN THE
UPPER 60S TO LOWER 70S... WITH LOW TEMPS IN THE 40S TO LOWER 50S.
MONDAY THROUGH WEDNESDAY: NEXT MID LEVEL DISTURBANCE IS EXPECTED TO
CROSS THE REGION ON TUESDAY... ALONG WITH A WEAK SURFACE TROUGH.
HOWEVER... WITH LACK OF ANY SIGNIFICANT MOISTURE RETURN WILL KEEP
POPS LOW AT THIS TIME. TEMPS EARLY TO MID NEXT WEEK ARE EXPECT TO
WARM AGAIN... WITH HIGHS IN THE 70S AND LOWS IN THE 50S.
&&
.AVIATION /00Z THURSDAY THROUGH MONDAY/...
AS OF 720 PM WEDNESDAY...
HIGH PRESSURE BUILDING INTO CENTRAL NC FROM THE NORTH WILL MAINTAIN
VFR CONDITIONS THROUGH THURSDAY MORNING. VFR CONDITIONS SHOULD
LARGELY CONTINUE INTO THE DAY ON THURSDAY...WITH THE EXCEPTION OF A
PERIOD OF MARGINAL MVFR CEILINGS WITH BASES BETWEEN 2500-3000KFT
ACROSS EASTERN AND POSSIBLY CENTRAL TERMINALS THURSDAY AFTERNOON
OWING TO NELY MARITIME FLOW WHICH COULD SUPPORT A BROKEN DIURNALLY
ENHANCED FLAT STRATOCU DECK. OTHERWISE NELY WINDS WILL PREVAIL WITH
WIND GUSTS OF 17 TO 20KTS...STRONGEST ACROSS EASTERN TERMINALS.
OUTLOOK...A DEVELOPING LOW PRESSURE SYSTEM IN VICINITY OF THE NE
GULF AND THE FL PENINSULA MAY SPREAD ENOUGH MOISTURE INTO EASTERN NC
BY LATE FRIDAY THROUGH SATURDAY TO CAUSE A PERIOD OF MVFR/IFR
CEILINGS. AT THIS TIME...APPEARS THE BEST CHANCE FOR RAIN WILL BE
CONFINED TO THE COASTAL AREAS. IMPROVING WEATHER CONDITIONS AND
ASSOCIATED VFR PARAMETERS ANTICIPATED SUNDAY AND MONDAY.
&&
.CLIMATE...
THE FOLLOWING ARE THE RECORD LOW TEMPERATURES FOR THU MORNING...AND
THE RECORD LOW MAXIMUM TEMPERATURES FOR TODAY:
WED 04/16 THU 04/17
LOW MAX/YEAR LOW/YEAR
FAY: 56/1950 31/1953
GSO: 48/1929 29/1953
RDU: 46/1890 29/1962
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
FREEZE WARNING FROM MIDNIGHT TONIGHT TO 9 AM EDT THURSDAY FOR
NCZ007>011-021>027-038>041-073>077-083>086.
&&
$$
SYNOPSIS...MWS
NEAR TERM...WSS/SMITH
SHORT TERM...WSS
LONG TERM...BSD
AVIATION...CBL/WSS
CLIMATE...MWS
AREA FORECAST DISCUSSION
NWS RALEIGH NC
255 PM EDT TUE APR 15 2014
.SYNOPSIS...A STRONG COLD FRONT WILL CROSS THE AREA THROUGH EARLY
EVENING. UNUSUALLY CHILLY HIGH PRESSURE WILL BUILD INTO THE REGION
FROM THE NORTH LATE TONIGHT THROUGH THURSDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 1010 AM TUESDAY...
HAVE JUST UPDATED THE FORECAST TO ACCOUNT FOR THE CONVECTIVE LINE
NOW EXITING THE ERN CWA. LATEST SURFACE ANALYSIS SHOWS THE FRONT NOW
ALONG THE NC MOUNTAINS AND EXPECT A STEADY EASTWARD PROGRESS THIS
AFTERNOON... PROPELLED BY THE DENSITY OF THE ANOMALOUSLY COLD
INCOMING AIR MASS AS WELL AS THE MID LEVEL TROUGH MOVING EAST OF THE
MS RIVER VALLEY. A FEW ROTATING ELEMENTS AND SHORT SEGMENTS WITH
ENHANCED WIND GUSTS WERE OBSERVED WITH THIS PRIMARY LINE OF
CONVECTION... AND AS THIS DEPARTS ALONG WITH THE BETTER
INSTABILITY... WE SHOULD SEE A BRIEF LULL WITHIN THE REARWARD
SUBSIDENCE ZONE. BUT ADDITIONAL CONVECTION NOW OVER S/E GA AND SC
SHOULD SPREAD UP INTO THE S/E CWA IN THE NEXT SEVERAL HOURS... AND
THIS EXTRAPOLATION IS SUPPORTED BY RAP/HRRR GUIDANCE. INSTABILITY IS
NOT PROJECTED TO BE PARTICULARLY STRONG WITH THIS (AROUND 250 J/KG
POTENTIALL APPROACHING 500 J/KG) BUT WILL LIKELY BE ACCOMPANIED BY
AN UPTICK IN LOW LEVEL SHEAR NEAR/EAST OF WHAT THE SHORT RANGE
MODELS INDICATE WILL BE A PREFRONTAL WEAK SURFACE LOW... AND IN FACT
THE RAP FORECAST SOUNDINGS SHOW A PERIOD OF CURVED HODOGRAPHS EARLY
THIS AFTERNOON. THIS MAY POSE OUR BEST CHANCE FOR AN ADDITIONAL
SEVERE WEATHER THREAT... IN THE FORM OF DAMAGING WINDS WITHIN BOWING
SEGMENTS AND AN ISOLATED WEAK TORNADO... LARGELY EAST OF I-95 AS
THIS IS WHERE THE SREF SHOWS THE BEST COMBINATION OF (MODEST)
INSTABILITY AND DEEP LAYER SHEAR AHEAD OF THE FRONT. THE THREAT OF
ANY STRONG STORMS SHOULD BE OVER (TO OUR EAST) BY 00Z. IN ANY
CASE... MOST PLACES SHOULD SEE AN ADDITIONAL PERIOD OF SHOWERS (IF
NOT STORMS) FROM LATE MORNING THROUGH MID/LATE AFTERNOON EITHER WITH
THE ACTIVITY TO OUR SOUTH OR ALONG AND JUST BEHIND THE COLD FRONT.
PW VALUES WILL REMAIN WELL ABOVE NORMAL... WITH ABUNDANT MOISTURE
WITH DEW POINTS HOLD IN THE 60S TO LOWER 70S. LIFT WILL BE AUGMENTED
BY UPPER DIVERGENCE IN THE RIGHT REAR QUAD OF THE SRLY JET STREAK TO
OUR NNW. SO... AFTER A SHORT LULL WILL TREND POPS BACK UP FOR THIS
AFTERNOON. ADJUSTED HOURLY TEMPS TOWARD THE GLAMP AND HRRR RAPID-
UPDATE GUIDANCE... TO INDICATE FALLING TEMPS IN THE WEST THIS
AFTERNOON. THIS YIELDS HIGHS FROM THE MID 60S WEST TO UPPER 70S
EAST. -GIH
MINIMAL ADJUSTMENT NEEDED FOR LOWS IN STRONG CAA TONIGHT...INTO THE
30 TO 37 DEGREE RANGE...COOLEST WEST. THE FREEZE WATCH HAS BEEN
CONSEQUENTLY BE UPGRADED TO A WARNING. -MWS
&&
.SHORT TERM /WEDNESDAY THROUGH THURSDAY NIGHT/...
AS OF 255 PM TUESDAY...
WED AND WED NIGHT: RISING HEIGHTS ALOFT/DNVA AND ASSOCIATED STRONG
SUBSIDENCE WILL RESULT IN FURTHER DEEP LAYER DRYING (SUNSHINE)
WED...FOLLOWED BY GENERALLY NEUTRAL VERTICAL MOTION...BUT WITH A
STILL STRONGLY CAPPED AND RESIDUALLY DRY REGIME OVER OUR REGION
THROUGH WED NIGHT. BENEATH THE STRONG SUBSIDENCE ALOFT...SURFACE
HIGH PRESSURE WILL CONSEQUENTLY BECOME UNSEASONABLY STRONG INTO THE
1040-1045 MB RANGE AS IT BUILDS FROM THE OH VALLEY TO NEW ENGLAND.
COOL NORTHEASTERLY FLOW AND DRY ADIABATIC MIXING THROUGH 900
MB...WITH A COUPLE OF DEGREES ADDED TO ACCOUNT FOR A USUAL SLIGHT
COOL BIAS WITH THIS TECHNIQUE LIKELY IN PART OWING TO A SUPER-
ADIABATIC NEAR SURFACE LAYER...SUPPORTS HIGHS IN THE LOWER TO MIDDLE
50S.
PROJECTED LOW LEVEL THICKNESS VALUES IN THE 1300-1310 METER RANGE AT
12Z THU...WITH OPTIMAL RADIATIONAL COOLING...WOULD SUPPORT MIDDLE
20S. HOWEVER...A PROJECTED 4-6 MB RISE IN MSL PRESSURE WITH THE
STRENGTHENING HIGH WED NIGHT WILL LIKELY MAINTAIN A NORTHEASTERLY
STIRRING FOR MOST AREAS OVERNIGHT...THOUGH WITH TYPICALLY
COOLER/SHELTERED AREA LIKELY TO EXPERIENCE PERIODS OF CALM. IN
ADDITION...MOISTURE ADVECTION IN NORTHEASTERLY FLOW BENEATH THE
CAPPING INVERSION MAY RESULT IN SCT TO BKN LOW CLOUDS MAINLY IN THE
COASTAL PLAIN LATE. AS SUCH...TEMPERATURES ARE APT TO DISPLAY A
RELATIVELY LARGE RANGE...FROM 28-30 DEGREES IN RURAL WESTERN
PIEDMONT LOCATIONS (IN CLOSEST PROXIMITY TO THE RIDGE AXIS) TO
AROUND FREEZING IN URBAN AREAS FROM RDU WESTWARD TO THE TRIAD...TO
33-37 DEGREES IN THE COASTAL PLAIN AND EASTERN SANDHILLS. -MWS
THURSDAY AND THURSDAY NIGHT...
HIGH PRESSURE AND DRY AIRMASS WILL MEAN FAIR WEATHER FOR THURSDAY.
HIGH CLOUDS WILL BE ON THE INCREASE LATE AS SW FLOW ALOFT INCREASES
AHEAD OF THE SHORT WAVE CROSSING THE SOUTHERN PLAINS. WITH LOW LEVEL
THICKNESSES REBOUNDING 30-40M FROM WEDNESDAY...LOOK FOR HIGHS IN THE
MID 60S. STILL COOL THURSDAY NIGHT WITH LOWS 5-10 DEGREES BELOW
NORMAL...RANGING FROM THE UPPER 30S TO LOWER 40S.
&&
.LONG TERM /FRIDAY THROUGH TUESDAY/...
AS OF 255 PM TUESDAY...
AT THE START OF FRIDAY...THE UPPER TROUGH WILL BE CROSSING THE
MISSISSIPPI RIVER VALLEY. MEANWHILE...A SOUTHERN STREAM SHORTWAVE
MOVING ACROSS THE NE GOMEX WILL MOVE TOWARD THE WESTERN ATLANTIC BY
DAYS END. IN RESPONSE...SURFACE LOW PRESSURE WILL DEVELOP IN
VICINITY OF THE GULF STREAM AND LIFT TO THE NE AS THE AFOREMENTIONED
SHORT WAVE MOVES EAST. MEANWHILE...THE NORTHERN STREAM UPPER TROUGH
AXIS WILL CROSS THE CAROLINAS BETWEEN 00-06Z SATURDAY. RIGHT NOW IT
APPEARS THAT THESE SYSTEMS WILL HAVE LITTLE IMPACT ON OUR SENSIBLE
WEATHER FRIDAY AND FRIDAY NIGHT...MAINLY BECAUSE...1) THE MOISTURE
ASSOC WITH THE SYSTEM OFF THE COAST IS PROGGED TO REMAIN WELL TO OUR
EAST...AND 2) THE NORTHERN TROUGH AXIS WILL MOVE ACROSS OUR AREA
MOISTURE-STARVED...WITH THE BULK OF ITS MOISTURE REMAINING WELL TO
OUR NORTH.
THEN IN THE WAKE OF THE UPPER TROUGH AXIS AND SFC COLD FRONT PASSAGE
SATURDAY MORNING...HIGH PRESSURE AND DRY AIRMASS WILL BUILD SOUTH ACROSS
THE CAROLINAS AND PROVIDE FAIR AND SEASONABLE WEATHER FOR THE REST OF
WEEKEND.
UNSETTLED WEATHER MAY RETURN EARLY NEXT WEEK WITH A SHORT WAVE
EMBEDDED IN THE NW FLOW MOVING ACROSS OUR AREA LATE MONDAY THROUGH
MIDDAY TUESDAY.
&&
.AVIATION /18Z TUESDAY THROUGH SUNDAY/...
AS OF 240 PM TUESDAY...
ADVERSE AVIATION CONDITIONS WILL DOMINATE FOR THE NEXT 6-9 HOURS OR
SO... FOLLOWED BY QUICK IMPROVEMENT TO VFR... BUT BRISK GUSTY WINDS
WILL PERSIST. A COLD FRONT IS CURRENTLY MOVING THROUGH CENTRAL NC.
PATCHY SHOWERS HAVE PRECEDED THIS FRONT ACROSS THE ENTIRE AREA IN
RECENT HOURS... BUT ALONG AND JUST AHEAD OF THIS FRONT... A SOLID
BAND OF HEAVY SHOWERS AND A FEW STORMS WILL SWEEP EASTWARD FROM NOW
THROUGH ABOUT 03Z. CURRENT TAFS REFLECT THIS WITH A PERIOD OF IFR
VSBYS AND MVFR TO IFR CIGS... AND STRONG GUSTY WINDS THROUGH LATE
THIS AFTERNOON. WINDS WILL SHIFT SUDDENLY WITH FRONTAL PASSAGE... AS
WINDS FROM THE SW SHIFT AROUND TO NW AND GUST UP TO 25-35 KTS... SO
AVIATION INTERESTS SHOULD KEEP A CLOSE TAB ON THE FRONTAL POSITION
IN THE NEXT SEVERAL HOURS. BETWEEN 02Z (WEST) AND 06Z (EAST)... CIGS
ARE LIKELY TO RISE TO VFR WITH P6SM VSBYS AS SKIES CLEAR OUT. BRISK
WINDS FROM NW WILL PERSIST THE REST OF TONIGHT... SUSTAINED NEAR 12-
18 KTS WITH A FEW GUSTS... THEN WILL SWING AROUND TO BE FROM THE
NORTH AND EVENTUALLY NORTHEAST VERY LATE TONIGHT THROUGH WED
MORNING... WITH VFR CONDITIONS LIKELY.
LOOKING BEYOND 18Z WED... VFR CONDITIONS LIKELY THROUGH THU...
ALTHOUGH THERE IS A CHANCE OF IFR CIGS WITH STRATUS AT FAY/RWI AS
SURFACE WINDS SHIFT AROUND TO BE FROM THE SE AND BRING IN ATLANTIC
LOW LEVEL MOISTURE. THIS CHANCE IS GREATER LATE THU NIGHT INTO FRI
MORNING. A MID LEVEL TROUGH WILL MOVE THROUGH THE EASTERN US FRI
THROUGH SAT... AND MAY BRING A PERIOD OF SUB-VFR CONDITIONS... BUT
UNCERTAINTY IN THE DETAILS WITH THIS IS HIGH. -GIH
&&
.CLIMATE...
THE FOLLOWING ARE THE RECORD LOW TEMPERATURES FOR WED AND THU MORNING...
AND THE RECORD LOW MAXIMUM TEMPERATURES FOR WED:
WED 04/16 THU 04/17
LOW/YEAR LOW MAX/YEAR LOW/YEAR
FAY: 28/1943 56/1950 31/1953
GSO: 25/1943 48/1929 29/1953
RDU: 28/1950 46/1890 29/1962
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
FREEZE WARNING FROM 3 AM TO 9 AM EDT WEDNESDAY FOR NCZ007>010-
021>026-038>041-073>077-083-084.
&&
$$
SYNOPSIS...HARTFIELD
NEAR TERM...HARTFIELD/MWS
SHORT TERM...MWS/KCP
LONG TERM...NP
AVIATION...HARTFIELD
CLIMATE...MWS
AREA FORECAST DISCUSSION
NWS RALEIGH NC
245 PM EDT TUE APR 15 2014
.SYNOPSIS...A STRONG COLD FRONT WILL CROSS THE AREA THROUGH EARLY
EVENING. UNUSUALLY CHILLY HIGH PRESSURE WILL BUILD INTO THE REGION
FROM THE NORTH LATE TONIGHT THROUGH THURSDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 1010 AM TUESDAY...
HAVE JUST UPDATED THE FORECAST TO ACCOUNT FOR THE CONVECTIVE LINE
NOW EXITING THE ERN CWA. LATEST SURFACE ANALYSIS SHOWS THE FRONT NOW
ALONG THE NC MOUNTAINS AND EXPECT A STEADY EASTWARD PROGRESS THIS
AFTERNOON... PROPELLED BY THE DENSITY OF THE ANOMALOUSLY COLD
INCOMING AIR MASS AS WELL AS THE MID LEVEL TROUGH MOVING EAST OF THE
MS RIVER VALLEY. A FEW ROTATING ELEMENTS AND SHORT SEGMENTS WITH
ENHANCED WIND GUSTS WERE OBSERVED WITH THIS PRIMARY LINE OF
CONVECTION... AND AS THIS DEPARTS ALONG WITH THE BETTER
INSTABILITY... WE SHOULD SEE A BRIEF LULL WITHIN THE REARWARD
SUBSIDENCE ZONE. BUT ADDITIONAL CONVECTION NOW OVER S/E GA AND SC
SHOULD SPREAD UP INTO THE S/E CWA IN THE NEXT SEVERAL HOURS... AND
THIS EXTRAPOLATION IS SUPPORTED BY RAP/HRRR GUIDANCE. INSTABILITY IS
NOT PROJECTED TO BE PARTICULARLY STRONG WITH THIS (AROUND 250 J/KG
POTENTIALL APPROACHING 500 J/KG) BUT WILL LIKELY BE ACCOMPANIED BY
AN UPTICK IN LOW LEVEL SHEAR NEAR/EAST OF WHAT THE SHORT RANGE
MODELS INDICATE WILL BE A PREFRONTAL WEAK SURFACE LOW... AND IN FACT
THE RAP FORECAST SOUNDINGS SHOW A PERIOD OF CURVED HODOGRAPHS EARLY
THIS AFTERNOON. THIS MAY POSE OUR BEST CHANCE FOR AN ADDITIONAL
SEVERE WEATHER THREAT... IN THE FORM OF DAMAGING WINDS WITHIN BOWING
SEGMENTS AND AN ISOLATED WEAK TORNADO... LARGELY EAST OF I-95 AS
THIS IS WHERE THE SREF SHOWS THE BEST COMBINATION OF (MODEST)
INSTABILITY AND DEEP LAYER SHEAR AHEAD OF THE FRONT. THE THREAT OF
ANY STRONG STORMS SHOULD BE OVER (TO OUR EAST) BY 00Z. IN ANY
CASE... MOST PLACES SHOULD SEE AN ADDITIONAL PERIOD OF SHOWERS (IF
NOT STORMS) FROM LATE MORNING THROUGH MID/LATE AFTERNOON EITHER WITH
THE ACTIVITY TO OUR SOUTH OR ALONG AND JUST BEHIND THE COLD FRONT.
PW VALUES WILL REMAIN WELL ABOVE NORMAL... WITH ABUNDANT MOISTURE
WITH DEW POINTS HOLD IN THE 60S TO LOWER 70S. LIFT WILL BE AUGMENTED
BY UPPER DIVERGENCE IN THE RIGHT REAR QUAD OF THE SRLY JET STREAK TO
OUR NNW. SO... AFTER A SHORT LULL WILL TREND POPS BACK UP FOR THIS
AFTERNOON. ADJUSTED HOURLY TEMPS TOWARD THE GLAMP AND HRRR RAPID-
UPDATE GUIDANCE... TO INDICATE FALLING TEMPS IN THE WEST THIS
AFTERNOON. THIS YIELDS HIGHS FROM THE MID 60S WEST TO UPPER 70S
EAST. -GIH
MINIMAL ADJUSTMENT NEEDED FOR LOWS IN STRONG CAA TONIGHT...INTO THE
30 TO 37 DEGREE RANGE...COOLEST WEST. THE FREEZE WATCH HAS BEEN
CONSEQUENTLY BE UPGRADED TO A WARNING. -MWS
&&
.SHORT TERM /WEDNESDAY THROUGH THURSDAY NIGHT/...
AS OF 235 AM TUESDAY...
WED AND WED NIGHT: RISING HEIGHTS ALOFT/DNVA AND ASSOCIATED STRONG
SUBSIDENCE WILL RESULT IN FURTHER DEEP LAYER DRYING (SUNSHINE)
WED...FOLLOWED BY GENERALLY NEUTRAL VERTICAL MOTION...BUT WITH A
STILL STRONGLY CAPPED AND RESIDUALLY DRY REGIME OVER OUR REGION
THROUGH WED NIGHT. BENEATH THE STRONG SUBSIDENCE ALOFT...SURFACE
HIGH PRESSURE WILL CONSEQUENTLY BECOME UNSEASONABLY STRONG INTO THE
1040-1045 MB RANGE AS IT BUILDS FROM THE OH VALLEY TO NEW ENGLAND.
COOL NORTHEASTERLY FLOW AND DRY ADIABATIC MIXING THROUGH 900
MB...WITH A COUPLE OF DEGREES ADDED TO ACCOUNT FOR A USUAL SLIGHT
COOL BIAS WITH THIS TECHNIQUE LIKELY IN PART OWING TO A SUPER-
ADIABATIC NEAR SURFACE LAYER...SUPPORTS HIGHS IN THE LOWER TO MIDDLE
50S.
PROJECTED LOW LEVEL THICKNESS VALUES IN THE 1300-1310 METER RANGE AT
12Z THU...WITH OPTIMAL RADIATIONAL COOLING...WOULD SUPPORT MIDDLE
20S. HOWEVER...A PROJECTED 4-6 MB RISE IN MSL PRESSURE WITH THE
STRENGTHENING HIGH WED NIGHT WILL LIKELY MAINTAIN A NORTHEASTERLY
STIRRING FOR MOST AREAS OVERNIGHT...THOUGH WITH TYPICALLY
COOLER/SHELTERED AREA LIKELY TO EXPERIENCE PERIODS OF CALM. IN
ADDITION...MOISTURE ADVECTION IN NORTHEASTERLY FLOW BENEATH THE
CAPPING INVERSION MAY RESULT IN SCT TO BKN LOW CLOUDS MAINLY IN THE
COASTAL PLAIN LATE. AS SUCH...TEMPERATURES ARE APT TO DISPLAY A
RELATIVELY LARGE RANGE...FROM 28-30 DEGREES IN RURAL WESTERN
PIEDMONT LOCATIONS (IN CLOSEST PROXIMITY TO THE RIDGE AXIS) TO
AROUND FREEZING IN URBAN AREAS FROM RDU WESTWARD TO THE TRIAD...TO
33-37 DEGREES IN THE COASTAL PLAIN AND EASTERN SANDHILLS. -MWS
THURSDAY THROUGH THURSDAY NIGHT: THIS PERIOD SHOULD REMAIN DRY WITH
HIGH PRESSURE RIDGING IN FROM THE NORTHEAST...ALTHOUGH EXPECT CLOUDS
TO INCREASE DURING THE EVE/OVERNIGHT...ESPECIALLY ACROSS THE SOUTH
AND EAST...AS A LOW DEVELOPS OFF THE COAST. WITH THE CONTINUED NE
FLOW AND CAA...STILL EXPECT TEMPS TO BE BELOW NORMAL. HOWEVER...
GIVEN LOW-LEVEL THICKNESSES INCREASING FROM THE PREVIOUS NIGHT BY A
GOOD 30-40 METERS...EXPECT TEMPS TO INCREASE BY 5-10 DEGREES...HIGHS
IN THE LOW TO MID 60S AND LOWS IN THE UPPER 30S TO LOW 40S. -KCP
&&
.LONG TERM /FRIDAY THROUGH MONDAY/...
AS OF 300 AM TUESDAY...
THERE IS STILL A SLIGHT CHANCE OF RAIN ACROSS THE SOUTHEAST FRIDAY
NIGHT/SATURDAY MORNING AS THE ELONGATED LOW OFF THE COAST MOVES AWAY
FROM THE AREA...OTHERWISE THE LATEST GFS AND ECMWF RUNS KEEP THE
FORECAST DRY THROUGH MONDAY. AN UPPER LEVEL LOW SKIRTS NORTH OF
CENTRAL NC SATURDAY NIGHT/SUNDAY. THE GFS IS A BIT MORE AMPLIFIED
WITH THE LOW...BRINGING IT CLOSER TO THE AREA. DESPITE THE STRONG
UPPER LEVEL FORCING AND MOISTURE IN THE UPPER LEVELS...THE DRY AIR
EXPECTED IN THE MID LEVELS MAY BE ENOUGH TO KEEP THINGS DRY. HIGHS
FRIDAY IN THE MID TO UPPER 60S WITH LOWS IN THE MID 40S TO AROUND 50
DEGREES. HIGH PRESSURE TO THE NORTH WILL RIDGE INTO THE AREA SUNDAY
AND MONDAY. ASIDE FROM SOME HIGH CLOUDS...EXPECT EASTER SUNDAY TO BE
DRY AND MOSTLY SUNNY. HIGHS MAINLY IN THE LOW TO MID 70S WITH LOWS
IN THE MID TO UPPER 40S THROUGH THE END OF THE PERIOD.
&&
.AVIATION /18Z TUESDAY THROUGH SUNDAY/...
AS OF 240 PM TUESDAY...
ADVERSE AVIATION CONDITIONS WILL DOMINATE FOR THE NEXT 6-9 HOURS OR
SO... FOLLOWED BY QUICK IMPROVEMENT TO VFR... BUT BRISK GUSTY WINDS
WILL PERSIST. A COLD FRONT IS CURRENTLY MOVING THROUGH CENTRAL NC.
PATCHY SHOWERS HAVE PRECEDED THIS FRONT ACROSS THE ENTIRE AREA IN
RECENT HOURS... BUT ALONG AND JUST AHEAD OF THIS FRONT... A SOLID
BAND OF HEAVY SHOWERS AND A FEW STORMS WILL SWEEP EASTWARD FROM NOW
THROUGH ABOUT 03Z. CURRENT TAFS REFLECT THIS WITH A PERIOD OF IFR
VSBYS AND MVFR TO IFR CIGS... AND STRONG GUSTY WINDS THROUGH LATE
THIS AFTERNOON. WINDS WILL SHIFT SUDDENLY WITH FRONTAL PASSAGE... AS
WINDS FROM THE SW SHIFT AROUND TO NW AND GUST UP TO 25-35 KTS... SO
AVIATION INTERESTS SHOULD KEEP A CLOSE TAB ON THE FRONTAL POSITION
IN THE NEXT SEVERAL HOURS. BETWEEN 02Z (WEST) AND 06Z (EAST)... CIGS
ARE LIKELY TO RISE TO VFR WITH P6SM VSBYS AS SKIES CLEAR OUT. BRISK
WINDS FROM NW WILL PERSIST THE REST OF TONIGHT... SUSTAINED NEAR 12-
18 KTS WITH A FEW GUSTS... THEN WILL SWING AROUND TO BE FROM THE
NORTH AND EVENTUALLY NORTHEAST VERY LATE TONIGHT THROUGH WED
MORNING... WITH VFR CONDITIONS LIKELY.
LOOKING BEYOND 18Z WED... VFR CONDITIONS LIKELY THROUGH THU...
ALTHOUGH THERE IS A CHANCE OF IFR CIGS WITH STRATUS AT FAY/RWI AS
SURFACE WINDS SHIFT AROUND TO BE FROM THE SE AND BRING IN ATLANTIC
LOW LEVEL MOISTURE. THIS CHANCE IS GREATER LATE THU NIGHT INTO FRI
MORNING. A MID LEVEL TROUGH WILL MOVE THROUGH THE EASTERN US FRI
THROUGH SAT... AND MAY BRING A PERIOD OF SUB-VFR CONDITIONS... BUT
UNCERTAINTY IN THE DETAILS WITH THIS IS HIGH. -GIH
&&
.CLIMATE...
THE FOLLOWING ARE THE RECORD LOW TEMPERATURES FOR WED AND THU MORNING...
AND THE RECORD LOW MAXIMUM TEMPERATURES FOR WED:
WED 04/16 THU 04/17
LOW/YEAR LOW MAX/YEAR LOW/YEAR
FAY: 28/1943 56/1950 31/1953
GSO: 25/1943 48/1929 29/1953
RDU: 28/1950 46/1890 29/1962
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
FREEZE WARNING FROM 3 AM TO 9 AM EDT WEDNESDAY FOR NCZ007>010-
021>026-038>041-073>077-083-084.
&&
$$
SYNOPSIS...HARTFIELD
NEAR TERM...HARTFIELD/MWS
SHORT TERM...MWS/KCP
LONG TERM...KCP
AVIATION...HARTFIELD
CLIMATE...MWS
AREA FORECAST DISCUSSION
NWS RALEIGH NC
1010 AM EDT TUE APR 15 2014
.SYNOPSIS...WARM AND MOIST SOUTHERLY FLOW WILL PERSIST TODAY...
AHEAD OF A COLD FRONT THAT WILL CROSS THE REGION THIS AFTERNOON
THROUGH EARLY EVENING. UNUSUALLY CHILLY HIGH PRESSURE WILL BUILD
INTO THE AREA FROM THE NORTH TONIGHT THROUGH THURSDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 1010 AM TUESDAY...
HAVE JUST UPDATED THE FORECAST TO ACCOUNT FOR THE CONVECTIVE LINE
NOW EXITING THE ERN CWA. LATEST SURFACE ANALYSIS SHOWS THE FRONT NOW
ALONG THE NC MOUNTAINS AND EXPECT A STEADY EASTWARD PROGRESS THIS
AFTERNOON... PROPELLED BY THE DENSITY OF THE ANOMALOUSLY COLD
INCOMING AIR MASS AS WELL AS THE MID LEVEL TROUGH MOVING EAST OF THE
MS RIVER VALLEY. A FEW ROTATING ELEMENTS AND SHORT SEGMENTS WITH
ENHANCED WIND GUSTS WERE OBSERVED WITH THIS PRIMARY LINE OF
CONVECTION... AND AS THIS DEPARTS ALONG WITH THE BETTER
INSTABILITY... WE SHOULD SEE A BRIEF LULL WITHIN THE REARWARD
SUBSIDENCE ZONE. BUT ADDITIONAL CONVECTION NOW OVER S/E GA AND SC
SHOULD SPREAD UP INTO THE S/E CWA IN THE NEXT SEVERAL HOURS... AND
THIS EXTRAPOLATION IS SUPPORTED BY RAP/HRRR GUIDANCE. INSTABILITY IS
NOT PROJECTED TO BE PARTICULARLY STRONG WITH THIS (AROUND 250 J/KG
POTENTIALL APPROACHING 500 J/KG) BUT WILL LIKELY BE ACCOMPANIED BY
AN UPTICK IN LOW LEVEL SHEAR NEAR/EAST OF WHAT THE SHORT RANGE
MODELS INDICATE WILL BE A PREFRONTAL WEAK SURFACE LOW... AND IN FACT
THE RAP FORECAST SOUNDINGS SHOW A PERIOD OF CURVED HODOGRAPHS EARLY
THIS AFTERNOON. THIS MAY POSE OUR BEST CHANCE FOR AN ADDITIONAL
SEVERE WEATHER THREAT... IN THE FORM OF DAMAGING WINDS WITHIN BOWING
SEGMENTS AND AN ISOLATED WEAK TORNADO... LARGELY EAST OF I-95 AS
THIS IS WHERE THE SREF SHOWS THE BEST COMBINATION OF (MODEST)
INSTABILITY AND DEEP LAYER SHEAR AHEAD OF THE FRONT. THE THREAT OF
ANY STRONG STORMS SHOULD BE OVER (TO OUR EAST) BY 00Z. IN ANY
CASE... MOST PLACES SHOULD SEE AN ADDITIONAL PERIOD OF SHOWERS (IF
NOT STORMS) FROM LATE MORNING THROUGH MID/LATE AFTERNOON EITHER WITH
THE ACTIVITY TO OUR SOUTH OR ALONG AND JUST BEHIND THE COLD FRONT.
PW VALUES WILL REMAIN WELL ABOVE NORMAL... WITH ABUNDANT MOISTURE
WITH DEW POINTS HOLD IN THE 60S TO LOWER 70S. LIFT WILL BE AUGMENTED
BY UPPER DIVERGENCE IN THE RIGHT REAR QUAD OF THE SRLY JET STREAK TO
OUR NNW. SO... AFTER A SHORT LULL WILL TREND POPS BACK UP FOR THIS
AFTERNOON. ADJUSTED HOURLY TEMPS TOWARD THE GLAMP AND HRRR RAPID-
UPDATE GUIDANCE... TO INDICATE FALLING TEMPS IN THE WEST THIS
AFTERNOON. THIS YIELDS HIGHS FROM THE MID 60S WEST TO UPPER 70S
EAST. -GIH
MINIMAL ADJUSTMENT NEEDED FOR LOWS IN STRONG CAA TONIGHT...INTO THE
30 TO 37 DEGREE RANGE...COOLEST WEST. THE FREEZE WATCH HAS BEEN
CONSEQUENTLY BE UPGRADED TO A WARNING. -MWS
&&
.SHORT TERM /WEDNESDAY THROUGH THURSDAY NIGHT/...
AS OF 235 AM TUESDAY...
WED AND WED NIGHT: RISING HEIGHTS ALOFT/DNVA AND ASSOCIATED STRONG
SUBSIDENCE WILL RESULT IN FURTHER DEEP LAYER DRYING (SUNSHINE)
WED...FOLLOWED BY GENERALLY NEUTRAL VERTICAL MOTION...BUT WITH A
STILL STRONGLY CAPPED AND RESIDUALLY DRY REGIME OVER OUR REGION
THROUGH WED NIGHT. BENEATH THE STRONG SUBSIDENCE ALOFT...SURFACE
HIGH PRESSURE WILL CONSEQUENTLY BECOME UNSEASONABLY STRONG INTO THE
1040-1045 MB RANGE AS IT BUILDS FROM THE OH VALLEY TO NEW ENGLAND.
COOL NORTHEASTERLY FLOW AND DRY ADIABATIC MIXING THROUGH 900
MB...WITH A COUPLE OF DEGREES ADDED TO ACCOUNT FOR A USUAL SLIGHT
COOL BIAS WITH THIS TECHNIQUE LIKELY IN PART OWING TO A SUPER-
ADIABATIC NEAR SURFACE LAYER...SUPPORTS HIGHS IN THE LOWER TO MIDDLE
50S.
PROJECTED LOW LEVEL THICKNESS VALUES IN THE 1300-1310 METER RANGE AT
12Z THU...WITH OPTIMAL RADIATIONAL COOLING...WOULD SUPPORT MIDDLE
20S. HOWEVER...A PROJECTED 4-6 MB RISE IN MSL PRESSURE WITH THE
STRENGTHENING HIGH WED NIGHT WILL LIKELY MAINTAIN A NORTHEASTERLY
STIRRING FOR MOST AREAS OVERNIGHT...THOUGH WITH TYPICALLY
COOLER/SHELTERED AREA LIKELY TO EXPERIENCE PERIODS OF CALM. IN
ADDITION...MOISTURE ADVECTION IN NORTHEASTERLY FLOW BENEATH THE
CAPPING INVERSION MAY RESULT IN SCT TO BKN LOW CLOUDS MAINLY IN THE
COASTAL PLAIN LATE. AS SUCH...TEMPERATURES ARE APT TO DISPLAY A
RELATIVELY LARGE RANGE...FROM 28-30 DEGREES IN RURAL WESTERN
PIEDMONT LOCATIONS (IN CLOSEST PROXIMITY TO THE RIDGE AXIS) TO
AROUND FREEZING IN URBAN AREAS FROM RDU WESTWARD TO THE TRIAD...TO
33-37 DEGREES IN THE COASTAL PLAIN AND EASTERN SANDHILLS. -MWS
THURSDAY THROUGH THURSDAY NIGHT: THIS PERIOD SHOULD REMAIN DRY WITH
HIGH PRESSURE RIDGING IN FROM THE NORTHEAST...ALTHOUGH EXPECT CLOUDS
TO INCREASE DURING THE EVE/OVERNIGHT...ESPECIALLY ACROSS THE SOUTH
AND EAST...AS A LOW DEVELOPS OFF THE COAST. WITH THE CONTINUED NE
FLOW AND CAA...STILL EXPECT TEMPS TO BE BELOW NORMAL. HOWEVER...
GIVEN LOW-LEVEL THICKNESSES INCREASING FROM THE PREVIOUS NIGHT BY A
GOOD 30-40 METERS...EXPECT TEMPS TO INCREASE BY 5-10 DEGREES...HIGHS
IN THE LOW TO MID 60S AND LOWS IN THE UPPER 30S TO LOW 40S. -KCP
&&
.LONG TERM /FRIDAY THROUGH MONDAY/...
AS OF 300 AM TUESDAY...
THERE IS STILL A SLIGHT CHANCE OF RAIN ACROSS THE SOUTHEAST FRIDAY
NIGHT/SATURDAY MORNING AS THE ELONGATED LOW OFF THE COAST MOVES AWAY
FROM THE AREA...OTHERWISE THE LATEST GFS AND ECMWF RUNS KEEP THE
FORECAST DRY THROUGH MONDAY. AN UPPER LEVEL LOW SKIRTS NORTH OF
CENTRAL NC SATURDAY NIGHT/SUNDAY. THE GFS IS A BIT MORE AMPLIFIED
WITH THE LOW...BRINGING IT CLOSER TO THE AREA. DESPITE THE STRONG
UPPER LEVEL FORCING AND MOISTURE IN THE UPPER LEVELS...THE DRY AIR
EXPECTED IN THE MID LEVELS MAY BE ENOUGH TO KEEP THINGS DRY. HIGHS
FRIDAY IN THE MID TO UPPER 60S WITH LOWS IN THE MID 40S TO AROUND 50
DEGREES. HIGH PRESSURE TO THE NORTH WILL RIDGE INTO THE AREA SUNDAY
AND MONDAY. ASIDE FROM SOME HIGH CLOUDS...EXPECT EASTER SUNDAY TO BE
DRY AND MOSTLY SUNNY. HIGHS MAINLY IN THE LOW TO MID 70S WITH LOWS
IN THE MID TO UPPER 40S THROUGH THE END OF THE PERIOD.
&&
.AVIATION /12Z TUESDAY THROUGH SATURDAY/...
AS OF 740 AM TUESDAY...
24 HOUR TAF PERIOD: A LINE OF HEAVY SHOWERS AND THUNDERSTORMS
CONTINUES TO MOVE THROUGH THE AREA...APPROACHING KRWI...AND MOVING
OVER THE TERMINAL DURING THE NEXT HOUR OR TWO. WITH THE BREAK IN THE
PRECIP THIS MORNING AT THE OTHER TERMINALS...CONDITIONS HAVE/SHOULD
TEMPORARILY IMPROVE(D) BACK TO VFR/MVFR. ADDITIONAL SHOWERS AND
THUNDERSTORMS ARE EXPECTED THIS AFTERNOON AND WILL LIKELY RESULT IN
PERIODS OF REDUCED CIGS AND VISBYS. IN THE WAKE OF THESE AFT/EVE
SHOWERS AND STORMS...THE COLD FRONT WILL TRAVERSE FROM WEST TO EAST
THROUGH CENTRAL NC. ALTHOUGH WINDS WILL REMAIN STRONG THROUGH 12Z...
EXPECT THEM TO VEER TO THE WEST THEN NORTHWEST BEHIND THE FRONT. THE
GUSTS MAY BRIEFLY DIE OUT BETWEEN 06Z AND 12Z WEDNESDAY MORNING.
CIGS WILL LIFT AND VISBYS WILL IMPROVE BEHIND THE FRONT...WITH VFR
CONDITIONS EXPECTED FOR THE LAST 6-12 HOURS OF THE TAF PERIOD. -KC
LOOKING AHEAD: MOSTLY VFR CONDITIONS WILL PERSIST THROUGH THE END OF
THE WORK WEEK. THERE COULD BE SOME MORNING STRATUS BOTH FRIDAY AND
SATURDAY MORNING AS MOISTURE ONCE AGAIN INCREASES AHEAD OF OUR NEXT
SYSTEM APPROACHING FROM THE SOUTH THIS WEEKEND. -KRD
&&
.CLIMATE...
THE FOLLOWING ARE THE RECORD LOW TEMPERATURES FOR WED AND THU MORNING...
AND THE RECORD LOW MAXIMUM TEMPERATURES FOR WED:
WED 04/16 THU 04/17
LOW/YEAR LOW MAX/YEAR LOW/YEAR
FAY: 28/1943 56/1950 31/1953
GSO: 25/1943 48/1929 29/1953
RDU: 28/1950 46/1890 29/1962
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
FREEZE WARNING FROM 3 AM TO 9 AM EDT WEDNESDAY FOR NCZ007>010-
021>026-038>041-073>077-083-084.
&&
$$
SYNOPSIS...HARTFIELD
NEAR TERM...HARTFIELD/MWS
SHORT TERM...MWS/KCP
LONG TERM...KCP
AVIATION...KCP
CLIMATE...MWS
AREA FORECAST DISCUSSION
NWS NEWPORT/MOREHEAD CITY NC
438 AM EDT TUE APR 15 2014
.SYNOPSIS...
A COLD FRONT WILL APPROACH FROM THE WEST TODAY AND SLOWLY CROSS
THE REGION THIS EVENING. HIGH PRESSURE WILL BUILD IN FROM THE
NORTH WEDNESDAY INTO FRIDAY...THEN SLIDE OFFSHORE SATURDAY AS A
TROUGH OF LOW PRESSURE DEVELOPS NEAR THE COAST SATURDAY. HIGH
PRESSURE WILL BUILD INTO THE AREA SUNDAY AND MONDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
AS OF 4 AM TUE...STRONG...MOIST SOUTHERLY FLOW CONTINUES AHEAD
OF A ROBUST LONG WAVE TROUGH PRESENTLY OVER THE MISS RIVER VALLEY
WITH A SFC COLD FRONT ACROSS THE OHIO AND TENN RIVER VALLEYS. SCT-
NUMEROUS SHOWERS ARE LIFTING N OFF THE ATLANTIC AND ACROSS COASTAL
AREAS EARLY THIS MORNING...MAINLY EAST OF HIGHWAY 17...WITH MORE
ISOL SHOWERS ACROSS THE COASTAL PLAIN. FARTHER TO THE WEST...AN
AREA OF CONVECTION IS CURRENTLY LIFTING ACROSS UPSTATE SC INTO THE
WESTERN NC PIEDMONT. HRRR KEEPS THESE STORMS WEST OF THE AREA
EARLY THIS MORNING...BUT MESO MODELS LIFT AN AREA OF DIFF VORT
ADVECTION ACROSS THE AREA AFTER DAYBREAK AND ENHANCE COVERAGE OF
SHOWERS ACROSS EASTERN NC. INSTABILITY INCREASES AFTER DAYBREAK
AS WELL BRINGING INCREASING CONVECTIVE CHANCES. MODELS HAVE LI`S
INCREASING TO AROUND -2 TO -4 C AND CAPE AROUND 1000-1500 J/KG THIS
AFTERNOON WITH 0-6KM BULK SHEAR INCREASING TO 40-60 KT AHEAD OF
THE FRONT. THE SHEAR IS MAINLY UNIDIRECTIONAL SUGGESTING DAMAGING
WINDS AS THE MAIN THREAT OF SEVERE...WITH THE BEST CHANCE FOR
SEVERE STORMS FROM MID AFTERNOON TO MID EVENING ASSOC WITH STRONG
FRONTAL FORCING. STRONG SLY FLOW PERSISTS TODAY WITH WIND GUSTS
AROUND 25-35 MPH. MOVED THE START TIME OF THE WIND ADVISORY FOR
THE OBX AND CARTERET CO TO 4 PM AS MODELS SHOWING SLY WINDS
INCREASING TO ADVISORY CRITERIA JUST AHEAD OF THE FRONT. A VERY
MILD START THIS MORNING WITH TEMPS AROUND 70 AND DEWPOINT TEMPS IN
THE MID TO UPPER 60. MAINLY CLOUDY SKIES WILL KEEP SHORT
THERMOMETER WITH HIGH EXPECTED IN THE UPPER 70S INLAND AND LOW TO
MID 70S ALONG THE COAST.
&&
.SHORT TERM /TONIGHT/...
AS OF 4 AM TUE...THE AFOREMENTIONED COLD FRONT PROGGED TO BE
MOVING ACROSS THE COASTAL PLAIN AT THE START OF THE SHORT TERM
PERIOD WITH AN ON-GOING SEVERE THREAT ASSOC WITH STRONG FRONTAL
FORCING IN A MOIST AND UNSTABLE ENVIRONMENT. HOWEVER THE FRONT
IS EXPECTED TO BE PUSHING OFF THE COAST BETWEEN 00Z-02Z WITH THE
SEVERE THREAT QUICKLY ENDING AFTER FROPA. STRONG CAA DEVELOPS
BEHIND THE FRONT BRINGING NLY WINDS AROUND 15-25 MPH INLAND TO
25-35 MPH WITH HIGHER GUST ALONG THE OBX AND WILL CONTINUE THE
WIND ADVISORY INTO WEDNESDAY. THIS COULD BRING MINOR COASTAL
FLOODING ISSUES ACROSS THE OBX AND SOUTHERN PAMLICO SOUND AREAS AS
WELL...SEE BELOW FOR DISCUSSION. TEMPS EXPECTED TO FALL INTO THE
UPPER 30S INLAND TO MID 40S ALONG THE COAST BY DAYBREAK WEDNESDAY.
&&
.LONG TERM /WEDNESDAY THROUGH MONDAY/...
AS OF 225 AM TUE...MODELS IN DECENT AGREEMENT AT THE START OF THE
EXTENDED FORECAST PERIODS WITH NEARLY ZONAL FLOW BEHIND EXITING
TROUGH OVER THE SOUTHEAST. WILL SEE SOME DIFFERENCES STARTING
THURSDAY AS ECMWF SPINS UP A LOW OFFSHORE AND GFSENSEMBLE MAINTAINS
A TROUGH. THIS COULD EFFECT SURFACE WIND SPEED ALONG THE COASTAL
SECTIONS THROUGH THE END OF THE WORKWEEK. THIS DEEPER LOW PRESSURE
IS SUPPORTED BY WEAK UPPER LEVEL ENERGY NOTED IN ECMWF. DIFFERENCES
BECOME MORE SIGNIFICANT BY THE WEEKEND AS ECMWF DROPS A DEEP TROUGH
INTO FLORIDA WHILE THE GFS NOTES A WEAKER UPPER TROUGH. THIS AGAIN
AFFECTS THE SURFACE PATTERN WITH ECMWF DEVELOPING A DEEP SURFACE LOW
PRESSURE OFF THE FLORIDA COAST AND GFS KEEPING AN INVERTED TROUGH
OFFSHORE. CURRENT GFS IS TRENDING SOMEWHAT DEEPER WITH WEEKEND
TROUGH THAN PREVIOUS RUN.
NEARLY ZONAL FLOW AT THE BEGINNING OF THE FORECAST PERIOD WILL
BECOME SOUTHWESTERLY AS TROUGH DIGS INTO THE CENTRAL PLAINS STATES.
WEAK UPPER LEVEL IMPULSES WILL MOVE THROUGH THE SOUTHWEST FLOW
THROUGH THE REMAINDER OF THE WORK WEEK. AT THE SURFACE HIGH PRESSURE
WILL BUILD INTO CENTRAL PART OF NORTH CAROLINA WITH LOW PRESSURE
DEVELOPING OFFSHORE. COASTAL SECTIONS WILL HAVE BREEZY CONDITIONS
WITH A SMALL CHANCE OF SHOWERS...DEPENDING ON STRENGTH AND PLACEMENT
OF LOW PRESSURE OFFSHORE. THE STRONG NORTHERLY FLOW WILL KEEP
TEMPERATURES BELOW NORMAL WITH LOW TEMPERATURES IN THE MID 30S TO
LOWER 40S AND HIGH TEMPERATURES IN THE 50S WEDNESDAY. THIS PATTERN
WILL REMAIN THROUGH THE WORKWEEK WITH RISING HEIGHTS ALLOW
TEMPERATURES TO RISE INTO THE UPPER 50S TO LOWER 60S.
BY SATURDAY UPPER TROUGH WILL MOVE ACROSS THE EAST COAST WITH LOW
PRESSURE DEVELOPING OFF THE FLORIDA COAST...ACCORDING TO ECMWF. DUE
TO UNCERTAINTY IN THIS TIME PERIOD...WONT MAKE ANY CHANGES TO THE
GRIDS.
&&
.AVIATION /07Z TUESDAY THROUGH SATURDAY/...
SHORT TERM /THROUGH TONIGHT/...
AS OF 4 AM TUE...GENERALLY MVFR CONDITIONS EXPECTED INTO MID
AFTERNOON WITH SCT SHOWERS ACROSS RTES AHEAD OF A STRONG COLD
FRONT. COULD SEE A FEW THUNDERSTORMS THIS MORNING WITH INCREASING
INSTABILITY. STRONG SLY WINDS AROUND 15-20 KT WITH GUSTS AROUND 25
KT TODAY. BY MID TO LATE AFTERNOON THE FRONT WILL BE PUSHING INTO
RTES BRINGING STRONG FRONTAL FORCING AND THE CHANCE FOR STRONG TO
SEVERE THUNDERSTORMS AND CONDITIONS AOB IFR. WINDS BECOME NLY
AFTER FROPA WITH STRONG CAA DEVELOPING AND COULD SEE GUSTS AROUND
30 KT DURING EVENING...BUT WILL SEE CLEARING SKIES WITH VFR
CONDITIONS RETURNING LATE EVENING AND AFTER MIDNIGHT.
LONG TERM /WEDNESDAY THROUGH SATURDAY/...
AS OF 231 AM TUE...VFR CONDITIONS WILL PREDOMINATE THROUGH FRIDAY
WITH HIGH PRESSURE BUILDING IN THE CENTRAL PART OF NORTH CAROLINA.
MAIN PROBLEM WILL BE WIND WITH NORTHERLY FLOW GUSTING TO 25 KT ON
WEDNESDAY...STRONGEST NEARER THE COAST. MODELS TRENDING DRIER THAN
PREVIOUS RUNS...BUT MAY SEE SOME SUB VFR CONDITIONS SATURDAY WITH
ISOLATED SHOWERS.
&&
.MARINE...
SHORT TERM /THROUGH TUESDAY/...
AS OF 4 AM TUE...MARINE OBS SHOWING SLY WINDS AROUND 15-25 KT
WITH SEAS AROUND 4-7 FT MOST AREAS...BUT UP TO 9 FT OFFSHORE
ONSLOW BAY. WINDS INCREASE TO 20-30 KT TODAY AHEAD OF A STRONG
COLD FRONT APPROACHING FROM THE WEST WITH SEAS BUILDING TO 7-11
FT. FREQUENT GUSTS TO GALE FORCE LIKELY ACROSS THE CENTRAL WATERS
WITH BETTER MIXING HERE AND MOVED START TIME OF THE GALE WARNING
TO 18Z HERE. THE COLD FRONT WILL CROSS THE WATERS THIS EVENING
WITH STRONG NLY FLOW TO GALE FORCE DEVELOPING MOST AREAS...LIKELY
JUST BELOW GALE FOR THE PAMLICO AND NEUSE RIVER ZONES. SEAS BUILD
TO 10-15 FT NRN WATERS AFTER MIDNIGHT AND REMAIN AROUND 6-10 FT
SOUTHERN WATERS.
LONG TERM /WEDNESDAY THROUGH SATURDAY/...
AS OF 236 AM TUE...STRONG NORTHERLY FLOW WILL START THE PERIOD ON
WEDNESDAY BEHIND DEPARTING COLD FRONT. GALE FORCE SPEEDS EXPECTED
THROUGH MUCH OF THE DAY ON WEDNESDAY WITH TIGHT GRADIENT BETWEEN
THE FRONT AND HIGH PRESSURE BUILDING INTO THE CENTER PART OF THE
STATE. GRADIENT WILL LOOSEN WEDNESDAY AFTERNOON/EVENING...BUT
SPEEDS EXPECTED TO REMAIN IN THE 20 KN RANGE THURSDAY. SOME
DIFFERENCES IN MODELS BY THE END OF THE WEEK AND INTO THE WEEKEND
WITH STRENGTH OF LOW PRESSURE/TROUGH OFFSHORE DETERMINING SPEEDS
OVER THE WATERS. FOR NOW WILL STAY WITH 15 TO 20 KTS.
&&
.TIDES/COASTAL FLOODING...
ELEVATED WATER LEVELS CAN BE EXPECT AS A STRONG N/NE FLOW DEVELOPS
BEHIND A SHARP COLD FRONT LATE TUESDAY NIGHT AND EARLY WEDNESDAY.
THE STRONG WINDS COINCIDE WITH A HIGH ASTRONOMICAL CYCLE COMING
OUT OF THIS EARLY WEEKS FULL MOON. NW GALES GRADUALLY SHIFTING TO
N TONIGHT AND WEDNESDAY SUGGEST HIGHEST WATER LEVELS...AROUND 2-3
FT TIDAL ANOMALIES FOR THE CENTRAL AND SOUTHERN OBX ADJACENT TO
THE PAMLICO SOUND BASED ON COASTAL FLOOD CLIMATOLOGY. CERA
WEBSITE KEEPS MAX WATER LEVELS ANOMALIES BETWEEN 1.5-2 FT BUT FEEL
IT COULD BE A LITTLE HIGHER WITH MINOR IMPACTS AND WILL ISSUE A
COASTAL FLOOD ADVISORY FOR OBX DARE AND HYDE WITH THE MORNING
PACKAGE. WINDS DO NOT SHIFT TO NE UNTIL WED AFTERNOON AND ARE
DECREASING BELOW GALES AS THEY DO...SO AT THIS TIME THINK THE
SOUTHERN PAMLICO SOUND AND NEUSE/PAMLICO RIVER AREAS WILL HAVE
LESS OF AN IMPACT. THE HIGH WATER LEVELS WILL ONLY SLOWLY
SUBSIDE AS A MODERATE NNE FLOW IS MAINTAINED BETWEEN STRONG HIGH
PRES TO THE NORTH AND OFFSHORE LOW PRESSURE TROF THRU THE END OF
THE WEEK.
&&
NC...WIND ADVISORY FROM 4 PM THIS AFTERNOON TO 5 PM EDT WEDNESDAY
FOR NCZ095-103-104.
COASTAL FLOOD ADVISORY FROM 10 PM THIS EVENING TO 8 PM EDT
WEDNESDAY FOR NCZ103-104.
MARINE...SMALL CRAFT ADVISORY FROM 11 AM THIS MORNING TO 5 PM EDT
WEDNESDAY FOR AMZ136-137.
GALE WARNING FROM 8 PM THIS EVENING TO 5 PM EDT WEDNESDAY FOR
AMZ130-131-135-150.
GALE WARNING FROM 2 PM THIS AFTERNOON TO 5 PM EDT WEDNESDAY
FOR AMZ152-154.
GALE WARNING FROM 8 PM THIS EVENING TO 4 PM EDT WEDNESDAY FOR
AMZ156-158.
&&
$$
SYNOPSIS...SK
NEAR TERM...SK
SHORT TERM...SK
LONG TERM...CGG
AVIATION...CGG/SK
MARINE...CGG/SK
TIDES/COASTAL FLOODING...SK/BTC
AREA FORECAST DISCUSSION
NWS RALEIGH NC
303 AM EDT TUE APR 15 2014
.SYNOPSIS...WARM AND MOIST SOUTHERLY FLOW WILL PERSIST AHEAD OF A
COLD FRONT THAT WILL CROSS THE CAROLINAS THIS AFTERNOON AND EVENING.
UNSEASONABLY STRONG AND COOL HIGH PRESSURE WILL THEN BUILD EAST
ACROSS THE MIDDLE ATLANTIC REGION TONIGHT THROUGH THURSDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 1015 PM MONDAY...
WARM MOIST AIR CONTINUES TO FILTER INTO CENTRAL NC THIS EVENING WITH
DEWPOINTS INCREASING INTO THE LOWER TO MID 60S AS SOUTH TO
SOUTHEASTERLY FLOW IS INCREASING IN ADVANCE OF A STRONG COLD
FRONT... CURRENTLY EXTENDING FROM THE EASTERN GREAT LAKES REGION
SOUTH-SOUTHWESTWARD TO THE AROUND NEW ORLEANS. THIS FRONT WILL
CONTINUE PUSHING EASTWARD OVERNIGHT... APPROACHING THE CENTRAL TO
SOUTHERN APPALACHIANS BY 12Z TUESDAY. THE WEAK PRE-FRONTAL BAND OF
CONVECTION THAT MOVED ACROSS TN/GA/SC AND WESTERN NC EARLIER TODAY
WEAKENED FURTHER THIS EVENING AND HAS LEFT AN OUTFLOW BOUNDARY
ACROSS PORTIONS OF THE WESTERN PIEDMONT. NEW SHOWERS AND STORMS ARE
NOW FORMING ON THE BOUNDARY. INSTABILITY IS INCREASE ACROSS THE AREA
IN GENERAL... WITH A NOSE OF MLCAPE (SMALL AMOUNT 100-250 J/KG)
EXTENDING UP TOWARDS THE DAVIDSON/ROWAN COUNTY LINE. THIS COUPLE
WITH STRONG DEEP LAYER SHEAR (0-6 KM SHEAR OF AROUND 40-50 KTS) AND
A FAVORABLE LOW LEVEL WIND PROFILE (0-1KM SRH OF 150-200 M2/S2) HAS
YIELDED SOME WEAK ROTATION WITH THESE VERY SHALLOW SHOWERS/STORMS
FROM TIME TO TIME. AT THIS TIME DO NOT THINK ANY WEAK ROTATION WILL
RESULT IN ANY ISOLATED BRIEF TORNADOES AS THE UPDRAFTS DO NO APPEAR
STRONG ENOUGH. THAT SAID... WE WILL NEED TO KEEP AN EYE ON THE RADAR
FOR ANY QUICK SPIKE IN INTENSITY WITH THESE SHOWERS/STORMS SINCE
THEY ARE INVOF THE REMNANT OUTFLOW BOUNDARY FROM EARLIER.
GIVEN THE ABOVE MENTIONED DEEP SHEAR AND FAVORABLE ATLANTIC LOW
LEVEL SOUTHEASTERLY INFLOW WE WILL NEED TO WATCH ANY CONVECTION THAT
FORMS OVER THE AREA OVERNIGHT... ESPECIALLY WITH THE LATEST RAP
SHOWING AS MUCH AS 500 J/KG OF MLCAPE MOVING INTO OUR
SOUTH/SOUTHEASTERN HALF OF CENTRAL NC OVERNIGHT. LATEST HRRR AND RAP
SHOW AN INCREASE IN ACTIVITY AFTER 06Z TONIGHT. THUS... WILL
MAINTAIN HIGH POPS AFTER 06Z TONIGHT AND MAINTAIN MENTION OF SOME
STRONG WIND GUSTS. EXPECT OVERNIGHT LOWS WILL BE WARM GIVEN THE
INCREASING MOISTURE/CLOUD COVER. THUS... EXPECT LOW TEMPS WILL BE IN
THE LOWER TO MID 60S.
TUE-TUE NIGHT: WEAKENING LIFT BUT WITH INCREASING 0-3KM SHEAR MOVES
EAST ACROSS CENTRAL NORTH CAROLINA EARLY TUESDAY...THEN THERE IS
FORECAST A BRIEF RESPITE IN THE CHANCES FOR SHOWERS AROUND MID-
MORNING WITH A SLIGHT DECREASE IN 850MB THETA-E VALUES AND
INSTABILITY. AS THE AFTERNOON APPROACHES...850MB WINDS SHOULD
INCREASE TO 50 TO 55KT AS A 120KT 300MB JET MOVES THROUGH THE
AREA...COINCIDENT WITH THE RIGHT ENTRANCE REGION OF A 90KT 500MB
JET. WHILE 1000-500MB LAPSE RATES ARE ONLY FORECAST AROUND
6C/KM...AND THOSE MAINLY EAST OF U.S. 1... MUCAPE THAT INCREASES
OVERNIGHT TO NEARLY 1000J/KG ON THE NAM OVER THE FAR SOUTHWEST
PIEDMONT CONTINUES TO PUSH ACROSS CENTRAL NORTH CAROLINA WITH VALUES
FROM 1000-1500J/KG DURING TUESDAY. 0-3KM SHEAR IS ON THE ORDER OF 40-
50KT TUESDAY AFTERNOON...INCREASING FURTHER TOWARD THE INTERSTATE 95
CORRIDOR LATE. MODEST LAPSE RATES IN A BROADLY MOIST AIR MASS SHOULD
HELP TO LIMIT AVAILABLE INSTABILITY... BUT SYSTEM DYNAMICS ALONG AND
AHEAD OF THE FRONT COULD COMPENSATE FOR THIS AND MAKE FOR THE
POTENTIAL FOR ISOLATED SEVERE STORMS TUESDAY. IF A LOCATION SEEMED
TO HAVE A BETTER CHANCE OF ISOLATED SEVERE STORMS...IT WOULD SEEM TO
BE ALONG AND EAST OF U.S. 1 WHERE THE OVERALL INSTABILITY AND SHEAR
WILL BE BETTER TUESDAY AFTERNOON...AS LIFTED INDICES THERE SHOULD BE
-2C TO -4C...WITH BETTER HEATING EXPECTED. THE PRIMARY SEVERE THREAT
IS ANTICIPATED TO BE WIND...BUT WITH 0-3KM HELICITY VALUES FROM 100-
300 M2/S2...AN ISOLATED TORNADO CANNOT BE RULED OUT. HIGHS WERE
LEANED TOWARD THE WARMER MAV GUIDANCE ANTICIPATING A BREAK IN
PRECIPITATION DURING THE MORNING...UPPER 60S NORTHWEST TO AROUND 80
SOUTHEAST.
STRONG COLD AIR ADVECTION TAKES PLACE TUESDAY NIGHT AS HIGH PRESSURE
MOVES IN. ONCE THE STRONG MID-LEVEL TROUGH MOVES THROUGH THE THREAT
OF PRECIPITATION SHOULD END...THEN IMPACTS TURN TOWARD THE POTENTIAL
FOR FREEZING CONDITIONS. THE GUIDANCE HAS BEEN CONSISTENT
FORECASTING LOWS AT OR BELOW FREEZING FOR A COUPLE OF RUNS MAINLY
ALONG AND WEST OF INTERSTATE 95...AND WHILE WINDS IN MANY LOCATIONS
SHOULD STAY UP THROUGH A LARGE PART OF THE NIGHT IN A TIGHT GRADIENT
BEHIND THE COLD FRONT AS THE HIGH BUILDS IN...LATE AT NIGHT THERE
SHOULD BE JUST ENOUGH WIND REDUCTION IN COMBINATION WITH SIMPLE
ADVECTION TO RESULT IN SEVERAL AREAS WITH TEMPERATURES BELOW
FREEZING. WILL ISSUE A FREEZE WATCH FOR A LARGE PART OF CENTRAL
NORTH CAROLINA FOR TUESDAY NIGHT INTO EARLY WEDNESDAY MORNING...
KEEPING OUT THE IMMEDIATE INTERSTATE 95 CORRIDOR FOR NOW DUE TO
GREATER WIND AND MIXING EXPECTED THERE. LOWS TUESDAY NIGHT 29 TO 32
MOSTLY FROM U.S. 1 WEST...33 TO 37 IN THE INTERSTATE 95 CORRIDOR.
&&
.SHORT TERM /WEDNESDAY THROUGH THURSDAY NIGHT/...
AS OF 235 AM TUESDAY...
WED AND WED NIGHT: RISING HEIGHTS ALOFT/DNVA AND ASSOCIATED STRONG
SUBSIDENCE WILL RESULT IN FURTHER DEEP LAYER DRYING (SUNSHINE)
WED...FOLLOWED BY GENERALLY NEUTRAL VERTICAL MOTION...BUT WITH A
STILL STRONGLY CAPPED AND RESIDUALLY DRY REGIME OVER OUR REGION
THROUGH WED NIGHT. BENEATH THE STRONG SUBSIDENCE ALOFT...SURFACE
HIGH PRESSURE WILL CONSEQUENTLY BECOME UNSEASONABLY STRONG INTO THE
1040-1045 MB RANGE AS IT BUILDS FROM THE OH VALLEY TO NEW ENGLAND.
COOL NORTHEASTERLY FLOW AND DRY ADIABATIC MIXING THROUGH 900
MB...WITH A COUPLE OF DEGREES ADDED TO ACCOUNT FOR A USUAL SLIGHT
COOL BIAS WITH THIS TECHNIQUE LIKELY IN PART OWING TO A SUPER-
ADIABATIC NEAR SURFACE LAYER...SUPPORTS HIGHS IN THE LOWER TO MIDDLE
50S.
PROJECTED LOW LEVEL THICKNESS VALUES IN THE 1300-1310 METER RANGE AT
12Z THU...WITH OPTIMAL RADIATIONAL COOLING...WOULD SUPPORT MIDDLE
20S. HOWEVER...A PROJECTED 4-6 MB RISE IN MSL PRESSURE WITH THE
STRENGTHENING HIGH WED NIGHT WILL LIKELY MAINTAIN A NORTHEASTERLY
STIRRING FOR MOST AREAS OVERNIGHT...THOUGH WITH TYPICALLY
COOLER/SHELTERED AREA LIKELY TO EXPERIENCE PERIODS OF CALM. IN
ADDITION...MOISTURE ADVECTION IN NORTHEASTERLY FLOW BENEATH THE
CAPPING INVERSION MAY RESULT IN SCT TO BKN LOW CLOUDS MAINLY IN THE
COASTAL PLAIN LATE. AS SUCH...TEMPERATURES ARE APT TO DISPLAY A
RELATIVELY LARGE RANGE...FROM 28-30 DEGREES IN RURAL WESTERN
PIEDMONT LOCATIONS (IN CLOSEST PROXIMITY TO THE RIDGE AXIS) TO
AROUND FREEZING IN URBAN AREAS FROM RDU WESTWARD TO THE TRIAD...TO
33-37 DEGREES IN THE COASTAL PLAIN AND EASTERN SANDHILLS. -MWS
THURSDAY THROUGH THURSDAY NIGHT: THIS PERIOD SHOULD REMAIN DRY WITH
HIGH PRESSURE RIDGING IN FROM THE NORTHEAST...ALTHOUGH EXPECT CLOUDS
TO INCREASE DURING THE EVE/OVERNIGHT...ESPECIALLY ACROSS THE SOUTH
AND EAST...AS A LOW DEVELOPS OFF THE COAST. WITH THE CONTINUED NE
FLOW AND CAA...STILL EXPECT TEMPS TO BE BELOW NORMAL. HOWEVER...
GIVEN LOW-LEVEL THICKNESSES INCREASING FROM THE PREVIOUS NIGHT BY A
GOOD 30-40 METERS...EXPECT TEMPS TO INCREASE BY 5-10 DEGREES...HIGHS
IN THE LOW TO MID 60S AND LOWS IN THE UPPER 30S TO LOW 40S. -KCP
&&
.LONG TERM /FRIDAY THROUGH TUESDAY/...
AS OF 300 AM TUESDAY...
THERE IS STILL A SLIGHT CHANCE OF RAIN ACROSS THE SOUTHEAST FRIDAY
NIGHT/SATURDAY MORNING AS THE ELONGATED LOW OFF THE COAST MOVES AWAY
FROM THE AREA...OTHERWISE THE LATEST GFS AND ECMWF RUNS KEEP THE
FORECAST DRY THROUGH MONDAY. AN UPPER LEVEL LOW SKIRTS NORTH OF
CENTRAL NC SATURDAY NIGHT/SUNDAY. THE GFS IS A BIT MORE AMPLIFIED
WITH THE LOW...BRINGING IT CLOSER TO THE AREA. DESPITE THE STRONG
UPPER LEVEL FORCING AND MOISTURE IN THE UPPER LEVELS...THE DRY AIR
EXPECTED IN THE MID LEVELS MAY BE ENOUGH TO KEEP THINGS DRY. HIGHS
FRIDAY IN THE MID TO UPPER 60S WITH LOWS IN THE MID 40S TO AROUND 50
DEGREES. HIGH PRESSURE TO THE NORTH WILL RIDGE INTO THE AREA SUNDAY
AND MONDAY. ASIDE FROM SOME HIGH CLOUDS...EXPECT EASTER SUNDAY TO BE
DRY AND MOSTLY SUNNY. HIGHS MAINLY IN THE LOW TO MID 70S WITH LOWS
IN THE MID TO UPPER 40S THROUGH THE END OF THE PERIOD.
&&
.AVIATION /06Z TUESDAY THROUGH SATURDAY/...
AS OF 200 AM TUESDAY...
24 HOUR TAF PERIOD: MVFR/IFR CONDITIONS ACROSS THE AREA WILL LIKELY
DECREASE FURTHER INTO IFR/LIFR BY DAYBREAK TUESDAY. HEAVY SHOWERS
AND THUNDERSTORMS ARE APPROACHING FROM THE SOUTHWEST...ALREADY
IMPACTING KINT AND KGSO...AND LIKELY MOVING OVER KFAY AND KRDU OVER
THE NEXT COUPLE HOURS (AND KRWI THEREAFTER). THOUGH IT IS POSSIBLE
THE CIGS MAY IMPROVE SLIGHTLY WITH THESE HEAVY SHOWERS...VISBYS WILL
LIKELY DECREASE. AS ALREADY SEEN AT KINT AND KGSO...SOUTHWEST WINDS
WILL BECOME GUSTY (20-25 KTS) AS THE LOW LEVEL FLOW STRENGTHENS. IF
THERE IS A BREAK IN THE PRECIP TUESDAY MORNING...CONDITIONS MAY
IMPROVE BACK TO MVFR...BUT EXPECT MORE SHOWERS AND THUNDERSTORMS TO
MOVE ACROSS THE AREA AHEAD OF THE COLD FRONT...EXPECTED TO MOVE FROM
WEST TO EAST THROUGH CENTRAL NC DURING THE LATE AFTERNOON/EARLY
EVENING. ALTHOUGH WINDS WILL REMAIN STRONG AND GUSTY THROUGH THE TAF
PERIOD...EXPECT THEM TO VEER TO THE WEST THEN NORTHWEST BEHIND THE
FRONT. CIGS WILL LIFT AND VISBYS WILL IMPROVE BEHIND THE FRONT...
WITH VFR CONDITIONS EXPECTED BY THE END OF THE PERIOD. -KC
LOOKING AHEAD: MOSTLY VFR CONDITIONS WILL PERSIST THROUGH THE END OF
THE WORK WEEK. THERE COULD BE SOME MORNING STRATUS BOTH FRIDAY AND
SATURDAY MORNING AS MOISTURE ONCE AGAIN INCREASES AHEAD OF OUR NEXT
SYSTEM APPROACHING FROM THE SOUTH THIS WEEKEND. -KRD
&&
.CLIMATE...
THE FOLLOWING ARE THE RECORD LOW TEMPERATURES FOR WED AND THU MORNING...
AND THE RECORD LOW MAXIMUM TEMPERATURES FOR WED:
WED 04/16 THU 04/17
LOW/YEAR LOW MAX/YEAR LOW/YEAR
FAY: 28/1943 56/1950 31/1953
GSO: 25/1943 48/1929 29/1953
RDU: 28/1950 46/1890 29/1962
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
FREEZE WATCH FROM LATE TUESDAY NIGHT THROUGH WEDNESDAY MORNING
FOR NCZ007>010-021>026-038>041-073>077-083-084.
&&
$$
SYNOPSIS...MWS
NEAR TERM...BSD/DJF
SHORT TERM...MWS/KCP
LONG TERM...KCP
AVIATION...KCP/KRD
CLIMATE...MWS
AREA FORECAST DISCUSSION
NWS RALEIGH NC
254 AM EDT TUE APR 15 2014
.SYNOPSIS...WARM AND MOIST SOUTHERLY FLOW WILL PERSIST AHEAD OF A
COLD FRONT THAT WILL CROSS THE CAROLINAS THIS AFTERNOON AND EVENING.
UNSEASONABLY STRONG AND COOL HIGH PRESSURE WILL THEN BUILD EAST
ACROSS THE MIDDLE ATLANTIC REGION TONIGHT THROUGH THURSDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 1015 PM MONDAY...
WARM MOIST AIR CONTINUES TO FILTER INTO CENTRAL NC THIS EVENING WITH
DEWPOINTS INCREASING INTO THE LOWER TO MID 60S AS SOUTH TO
SOUTHEASTERLY FLOW IS INCREASING IN ADVANCE OF A STRONG COLD
FRONT... CURRENTLY EXTENDING FROM THE EASTERN GREAT LAKES REGION
SOUTH-SOUTHWESTWARD TO THE AROUND NEW ORLEANS. THIS FRONT WILL
CONTINUE PUSHING EASTWARD OVERNIGHT... APPROACHING THE CENTRAL TO
SOUTHERN APPALACHIANS BY 12Z TUESDAY. THE WEAK PRE-FRONTAL BAND OF
CONVECTION THAT MOVED ACROSS TN/GA/SC AND WESTERN NC EARLIER TODAY
WEAKENED FURTHER THIS EVENING AND HAS LEFT AN OUTFLOW BOUNDARY
ACROSS PORTIONS OF THE WESTERN PIEDMONT. NEW SHOWERS AND STORMS ARE
NOW FORMING ON THE BOUNDARY. INSTABILITY IS INCREASE ACROSS THE AREA
IN GENERAL... WITH A NOSE OF MLCAPE (SMALL AMOUNT 100-250 J/KG)
EXTENDING UP TOWARDS THE DAVIDSON/ROWAN COUNTY LINE. THIS COUPLE
WITH STRONG DEEP LAYER SHEAR (0-6 KM SHEAR OF AROUND 40-50 KTS) AND
A FAVORABLE LOW LEVEL WIND PROFILE (0-1KM SRH OF 150-200 M2/S2) HAS
YIELDED SOME WEAK ROTATION WITH THESE VERY SHALLOW SHOWERS/STORMS
FROM TIME TO TIME. AT THIS TIME DO NOT THINK ANY WEAK ROTATION WILL
RESULT IN ANY ISOLATED BRIEF TORNADOES AS THE UPDRAFTS DO NO APPEAR
STRONG ENOUGH. THAT SAID... WE WILL NEED TO KEEP AN EYE ON THE RADAR
FOR ANY QUICK SPIKE IN INTENSITY WITH THESE SHOWERS/STORMS SINCE
THEY ARE INVOF THE REMNANT OUTFLOW BOUNDARY FROM EARLIER.
GIVEN THE ABOVE MENTIONED DEEP SHEAR AND FAVORABLE ATLANTIC LOW
LEVEL SOUTHEASTERLY INFLOW WE WILL NEED TO WATCH ANY CONVECTION THAT
FORMS OVER THE AREA OVERNIGHT... ESPECIALLY WITH THE LATEST RAP
SHOWING AS MUCH AS 500 J/KG OF MLCAPE MOVING INTO OUR
SOUTH/SOUTHEASTERN HALF OF CENTRAL NC OVERNIGHT. LATEST HRRR AND RAP
SHOW AN INCREASE IN ACTIVITY AFTER 06Z TONIGHT. THUS... WILL
MAINTAIN HIGH POPS AFTER 06Z TONIGHT AND MAINTAIN MENTION OF SOME
STRONG WIND GUSTS. EXPECT OVERNIGHT LOWS WILL BE WARM GIVEN THE
INCREASING MOISTURE/CLOUD COVER. THUS... EXPECT LOW TEMPS WILL BE IN
THE LOWER TO MID 60S.
TUE-TUE NIGHT: WEAKENING LIFT BUT WITH INCREASING 0-3KM SHEAR MOVES
EAST ACROSS CENTRAL NORTH CAROLINA EARLY TUESDAY...THEN THERE IS
FORECAST A BRIEF RESPITE IN THE CHANCES FOR SHOWERS AROUND MID-
MORNING WITH A SLIGHT DECREASE IN 850MB THETA-E VALUES AND
INSTABILITY. AS THE AFTERNOON APPROACHES...850MB WINDS SHOULD
INCREASE TO 50 TO 55KT AS A 120KT 300MB JET MOVES THROUGH THE
AREA...COINCIDENT WITH THE RIGHT ENTRANCE REGION OF A 90KT 500MB
JET. WHILE 1000-500MB LAPSE RATES ARE ONLY FORECAST AROUND
6C/KM...AND THOSE MAINLY EAST OF U.S. 1... MUCAPE THAT INCREASES
OVERNIGHT TO NEARLY 1000J/KG ON THE NAM OVER THE FAR SOUTHWEST
PIEDMONT CONTINUES TO PUSH ACROSS CENTRAL NORTH CAROLINA WITH VALUES
FROM 1000-1500J/KG DURING TUESDAY. 0-3KM SHEAR IS ON THE ORDER OF 40-
50KT TUESDAY AFTERNOON...INCREASING FURTHER TOWARD THE INTERSTATE 95
CORRIDOR LATE. MODEST LAPSE RATES IN A BROADLY MOIST AIR MASS SHOULD
HELP TO LIMIT AVAILABLE INSTABILITY... BUT SYSTEM DYNAMICS ALONG AND
AHEAD OF THE FRONT COULD COMPENSATE FOR THIS AND MAKE FOR THE
POTENTIAL FOR ISOLATED SEVERE STORMS TUESDAY. IF A LOCATION SEEMED
TO HAVE A BETTER CHANCE OF ISOLATED SEVERE STORMS...IT WOULD SEEM TO
BE ALONG AND EAST OF U.S. 1 WHERE THE OVERALL INSTABILITY AND SHEAR
WILL BE BETTER TUESDAY AFTERNOON...AS LIFTED INDICES THERE SHOULD BE
-2C TO -4C...WITH BETTER HEATING EXPECTED. THE PRIMARY SEVERE THREAT
IS ANTICIPATED TO BE WIND...BUT WITH 0-3KM HELICITY VALUES FROM 100-
300 M2/S2...AN ISOLATED TORNADO CANNOT BE RULED OUT. HIGHS WERE
LEANED TOWARD THE WARMER MAV GUIDANCE ANTICIPATING A BREAK IN
PRECIPITATION DURING THE MORNING...UPPER 60S NORTHWEST TO AROUND 80
SOUTHEAST.
STRONG COLD AIR ADVECTION TAKES PLACE TUESDAY NIGHT AS HIGH PRESSURE
MOVES IN. ONCE THE STRONG MID-LEVEL TROUGH MOVES THROUGH THE THREAT
OF PRECIPITATION SHOULD END...THEN IMPACTS TURN TOWARD THE POTENTIAL
FOR FREEZING CONDITIONS. THE GUIDANCE HAS BEEN CONSISTENT
FORECASTING LOWS AT OR BELOW FREEZING FOR A COUPLE OF RUNS MAINLY
ALONG AND WEST OF INTERSTATE 95...AND WHILE WINDS IN MANY LOCATIONS
SHOULD STAY UP THROUGH A LARGE PART OF THE NIGHT IN A TIGHT GRADIENT
BEHIND THE COLD FRONT AS THE HIGH BUILDS IN...LATE AT NIGHT THERE
SHOULD BE JUST ENOUGH WIND REDUCTION IN COMBINATION WITH SIMPLE
ADVECTION TO RESULT IN SEVERAL AREAS WITH TEMPERATURES BELOW
FREEZING. WILL ISSUE A FREEZE WATCH FOR A LARGE PART OF CENTRAL
NORTH CAROLINA FOR TUESDAY NIGHT INTO EARLY WEDNESDAY MORNING...
KEEPING OUT THE IMMEDIATE INTERSTATE 95 CORRIDOR FOR NOW DUE TO
GREATER WIND AND MIXING EXPECTED THERE. LOWS TUESDAY NIGHT 29 TO 32
MOSTLY FROM U.S. 1 WEST...33 TO 37 IN THE INTERSTATE 95 CORRIDOR.
&&
.SHORT TERM /WEDNESDAY THROUGH THURSDAY NIGHT/...
AS OF 235 AM TUESDAY...
WED AND WED NIGHT: RISING HEIGHTS ALOFT/DNVA AND ASSOCIATED STRONG
SUBSIDENCE WILL RESULT IN FURTHER DEEP LAYER DRYING (SUNSHINE)
WED...FOLLOWED BY GENERALLY NEUTRAL VERTICAL MOTION...BUT WITH A
STILL STRONGLY CAPPED AND RESIDUALLY DRY REGIME OVER OUR REGION
THROUGH WED NIGHT. BENEATH THE STRONG SUBSIDENCE ALOFT...SURFACE
HIGH PRESSURE WILL CONSEQUENTLY BECOME UNSEASONABLY STRONG INTO THE
1040-1045 MB RANGE AS IT BUILDS FROM THE OH VALLEY TO NEW ENGLAND.
COOL NORTHEASTERLY FLOW AND DRY ADIABATIC MIXING THROUGH 900
MB...WITH A COUPLE OF DEGREES ADDED TO ACCOUNT FOR A USUAL SLIGHT
COOL BIAS WITH THIS TECHNIQUE LIKELY IN PART OWING TO A SUPER-
ADIABATIC NEAR SURFACE LAYER...SUPPORTS HIGHS IN THE LOWER TO MIDDLE
50S.
PROJECTED LOW LEVEL THICKNESS VALUES IN THE 1300-1310 METER RANGE AT
12Z THU...WITH OPTIMAL RADIATIONAL COOLING...WOULD SUPPORT MIDDLE
20S. HOWEVER...A PROJECTED 4-6 MB RISE IN MSL PRESSURE WITH THE
STRENGTHENING HIGH WED NIGHT WILL LIKELY MAINTAIN A NORTHEASTERLY
STIRRING FOR MOST AREAS OVERNIGHT...THOUGH WITH TYPICALLY
COOLER/SHELTERED AREA LIKELY TO EXPERIENCE PERIODS OF CALM. IN
ADDITION...MOISTURE ADVECTION IN NORTHEASTERLY FLOW BENEATH THE
CAPPING INVERSION MAY RESULT IN SCT TO BKN LOW CLOUDS MAINLY IN THE
COASTAL PLAIN LATE. AS SUCH...TEMPERATURES ARE APT TO DISPLAY A
RELATIVELY LARGE RANGE...FROM 28-30 DEGREES IN RURAL WESTERN
PIEDMONT LOCATIONS (IN CLOSEST PROXIMITY TO THE RIDGE AXIS) TO
AROUND FREEZING IN URBAN AREAS FROM RDU WESTWARD TO THE TRIAD...TO
33-37 DEGREES IN THE COASTAL PLAIN AND EASTERN SANDHILLS. -MWS
THURSDAY THROUGH THURSDAY NIGHT: THIS PERIOD SHOULD REMAIN DRY WITH
HIGH PRESSURE RIDGING IN FROM THE NORTHEAST...ALTHOUGH EXPECT CLOUDS
TO INCREASE DURING THE EVE/OVERNIGHT...ESPECIALLY ACROSS THE SOUTH
AND EAST...AS A LOW DEVELOPS OFF THE COAST. WITH THE CONTINUED NE
FLOW AND CAA...STILL EXPECT TEMPS TO BE BELOW NORMAL. HOWEVER...
GIVEN LOW-LEVEL THICKNESSES INCREASING FROM THE PREVIOUS NIGHT BY A
GOOD 30-40 METERS...EXPECT TEMPS TO INCREASE BY 5-10 DEGREES...HIGHS
IN THE LOW TO MID 60S AND LOWS IN THE UPPER 30S TO LOW 40S. -KCP
&&
.LONG TERM /FRIDAY THROUGH MONDAY/...
AS OF 300 PM MONDAY...
FOR FRI THROUGH MON: LONGWAVE TROUGHING THAT DRIFTS EAST ACROSS
CENTRAL NOAM THU IS EXPECTED TO AMPLIFY SLIGHTLY AS IT HEADS
EASTWARD INTO ERN NOAM FRI/SAT. THE APPROACH OF THIS TROUGH IS
EXPECTED TO DRAW ENERGY FROM THE NRN GULF TOWARD THE NE... INDUCING
SURFACE CYCLOGENESIS OVER THE NE GULF OR FL... WHICH WOULD THEN
TRACK NORTHEASTWARD OVER OR JUST OFF THE SOUTHEAST COAST FRI
NIGHT/SAT. THE GFS IS FAIRLY DRY HERE... HOLDING ITS SRN STREAM
PRECIP TO OUR SE AND ANY NRN STREAM PRECIP TO OUR NORTH. THE ECMWF
IS STRONGER WITH THE SOUTHERN WAVE... DEEPENING IT OVER SRN GA AND
FL... BUT IT TOO HOLDS MOST OF THE PRECIP WITH THIS WAVE TO OUR SE.
WILL RETAIN THE BASIC STRUCTURE OF THE PRECIP CHANCES WE CURRENTLY
HAVE IN THERE... BUT REDUCE THEM AND CONFINE THE BETTER POPS TO OUR
SOUTHEAST SECTIONS. AFTER BOTH THE NORTHERN AND SOUTHERN TROUGHS
SHIFT EAST OF OUR LONGITUDE LATE SAT INTO SAT NIGHT... MID LEVEL
RIDGING OVERSPREADS THE GULF/MIDSOUTH INTO THE SOUTHEAST AS ANOTHER
HIGH PRESSURE BRIEFLY BUILDS IN FROM THE NORTH ON SUNDAY. EXPECT
DECREASING CLOUDS SAT NIGHT AND A GOOD BIT OF SUNSHINE EASTER SUNDAY
WITH MODERATING TEMPS CLOSE TO SEASONAL NORMALS. LOW CONFIDENCE IN
MONDAY`S FORECAST AS THE GFS DEEPENS A MID LEVEL LOW OVER THE LOWER
GREAT LAKES... LEADING TO SURFACE LOW FORMATION ALONG A ROUGHLY E-W
FRONT ACROSS THE REGION WITH WIDESPREAD RAIN MOVING IN... WHILE THE
ECMWF IS MUCH WEAKER/SLOWER AND KEEPS NC DRY MON. WILL GO WITH THE
WEAKER ECMWF SOLUTION AND KEEP MONDAY DRY FOR NOW... BUT STAY TUNED.
EXPECT TEMPS CLOSE TO NORMAL MON.
&&
.AVIATION /06Z TUESDAY THROUGH SATURDAY/...
AS OF 200 AM TUESDAY...
24 HOUR TAF PERIOD: MVFR/IFR CONDITIONS ACROSS THE AREA WILL LIKELY
DECREASE FURTHER INTO IFR/LIFR BY DAYBREAK TUESDAY. HEAVY SHOWERS
AND THUNDERSTORMS ARE APPROACHING FROM THE SOUTHWEST...ALREADY
IMPACTING KINT AND KGSO...AND LIKELY MOVING OVER KFAY AND KRDU OVER
THE NEXT COUPLE HOURS (AND KRWI THEREAFTER). THOUGH IT IS POSSIBLE
THE CIGS MAY IMPROVE SLIGHTLY WITH THESE HEAVY SHOWERS...VISBYS WILL
LIKELY DECREASE. AS ALREADY SEEN AT KINT AND KGSO...SOUTHWEST WINDS
WILL BECOME GUSTY (20-25 KTS) AS THE LOW LEVEL FLOW STRENGTHENS. IF
THERE IS A BREAK IN THE PRECIP TUESDAY MORNING...CONDITIONS MAY
IMPROVE BACK TO MVFR...BUT EXPECT MORE SHOWERS AND THUNDERSTORMS TO
MOVE ACROSS THE AREA AHEAD OF THE COLD FRONT...EXPECTED TO MOVE FROM
WEST TO EAST THROUGH CENTRAL NC DURING THE LATE AFTERNOON/EARLY
EVENING. ALTHOUGH WINDS WILL REMAIN STRONG AND GUSTY THROUGH THE TAF
PERIOD...EXPECT THEM TO VEER TO THE WEST THEN NORTHWEST BEHIND THE
FRONT. CIGS WILL LIFT AND VISBYS WILL IMPROVE BEHIND THE FRONT...
WITH VFR CONDITIONS EXPECTED BY THE END OF THE PERIOD. -KC
LOOKING AHEAD: MOSTLY VFR CONDITIONS WILL PERSIST THROUGH THE END OF
THE WORK WEEK. THERE COULD BE SOME MORNING STRATUS BOTH FRIDAY AND
SATURDAY MORNING AS MOISTURE ONCE AGAIN INCREASES AHEAD OF OUR NEXT
SYSTEM APPROACHING FROM THE SOUTH THIS WEEKEND. -KRD
&&
.CLIMATE...
THE FOLLOWING ARE THE RECORD LOW TEMPERATURES FOR WED AND THU MORNING...
AND THE RECORD LOW MAXIMUM TEMPERATURES FOR WED:
WED 04/16 THU 04/17
LOW/YEAR LOW MAX/YEAR LOW/YEAR
FAY: 28/1943 56/1950 31/1953
GSO: 25/1943 48/1929 29/1953
RDU: 28/1950 46/1890 29/1962
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
FREEZE WATCH FROM LATE TUESDAY NIGHT THROUGH WEDNESDAY MORNING
FOR NCZ007>010-021>026-038>041-073>077-083-084.
&&
$$
SYNOPSIS...MWS
NEAR TERM...BSD/DJF
SHORT TERM...MWS/KCP
LONG TERM...HARTFIELD
AVIATION...KC/KRD
CLIMATE...MWS
PREVIOUS FORECAST DISCUSSION >
WESTERLY MID LEVEL FLOW WITH SURFACE HIGH PRESSURE SLIDING OFF TO
THE EAST BECOMING CENTERED OVER NEW ENGLAND BY THURSDAY MORNING. A
SOUTHERLY RETURN FLOW WILL BEGIN TO DEVELOP LATE TONIGHT ON THE BACK
SIDE OF THIS RETREATING SFC HIGH. SKIES WILL START OUT MAINLY CLEAR
THIS EVENING WITH AN INCREASE IN HIGH LEVEL CLOUDS OVERNIGHT.
QUESTION REVOLVES AROUND WHETHER WIND/CLOUDS WILL MITIGATE FROST
DEVELOPMENT TONIGHT. EXPECT THAT SOME FROST WILL DEVELOP ESPECIALLY
IN PROTECTED AREAS. WILL CONTINUE FROST ADVISORY ACRS THE SOUTH
WHERE THE SEASON HAS STARTED. HAVE TAKEN FROST MENTION OUT OF
WEST CENTRAL OHIO WHERE WINDS PICK UP IN RESPONSE TO THE INCREASING
GRADIENT. LOWS EXPECTED TO RANGE FROM THE LOWER 30S NE TO THE MID
30S SOUTH.
&&
.SHORT TERM /6 AM THURSDAY MORNING THROUGH FRIDAY NIGHT/...
A RETURN SOUTHERLY FLOW WILL DEVELOP BETWEEN RETREATING SFC HIGH
PRESSURE AND WEAK COLD FRONT TO OUR WEST. THIS SRLY FLOW WILL ALLOW
TEMPERATURES TO MODERATE TO READINGS SLIGHTLY ABOVE NORMAL ON
THURSDAY. EXPECT A FAIR AMOUNT OF HIGH LEVEL CLOUDS MAINLY EARLY
AND THEN DECREASING AS THE OHIO VALLEY GETS INTO THE WARM SECTOR.
EXPECT HIGHS TO RANGE FROM THE LOWER 60S NE TO THE UPPER 60S SW.
MID LEVEL SHORTWAVES TO PHASE TO OUR WEST WITH A LONG WAVE TROF AXIS
PIVOTING THRU THE OHIO VALLEY FRIDAY/FRIDAY NIGHT. EXPECT SOME
INCREASE IN CLOUDS THICKEST ACRS THE WEST LATE THURSDAY NIGHT. WITH
SOME WIND AROUND 5 KTS AND INCREASE IN CLOUDS EXPECT THURSDAY NIGHTS
LOWS TO BE CLOSE TO NORMAL...RANGING FROM NEAR 40 NE TO THE LOWER/MID
40S SW.
WEAK SFC COLD FRONT TO PIVOT EAST THRU ILN/S FA FRIDAY/FRIDAY
EVENING. MODEL SOLN DIFFERENCES EXIST REGARDING MOISTURE/TIMING WITH
THIS WEAK FRONT. MAIN SFC LOW WELL TO OUR NORTH AND FORCING IS VERY
WEAK OVER ILN/S FA. WILL CONTINUE TO LIMIT POPS TO CHC IN THE WEST
FRIDAY AFTN AND THEN ONLY ALLOW SLIGHT CHC IN THE SOUTHEAST. EXPECT
HIGHS FROM THE LOWER 60S NW TO THE UPPER 60S SE FRIDAY. LOWS
FRIDAY NIGHT TO RANGE FROM THE UPPER 30S NW TO THE MID 40S SE.
&&
.LONG TERM /SATURDAY THROUGH WEDNESDAY/...
HIGH PRESSURE STRETCHING FROM SOUTHEAST CANADA THROUGH THE GREAT
LAKES AND OHIO VALLEY WILL KEEP DRY WEATHER OVER THE AREA SATURDAY
AND SUNDAY. A COLD FRONT WILL ENTER THE REGION MONDAY. GFS AND
ECMWF BOTH INDICATE THE FRONT...BUT DIFFERENCES IN TIMING
EXIST...WITH GFS FASTER AND ECMWF OFFERING A SLOWER SOLUTION.
SPLIT THE DIFFERENCE BETWEEN MODELS AND WENT WITH A MODEL
BLEND...WHICH YIELDS THE LIKELIHOOD FOR SHOWERS MONDAY AND MONDAY
NIGHT. WITH MODELS SHOWING SCANT INSTABILITY AND RATHER WEAK WIND
FIELDS ALONG THE FRONT...DECIDED TO OMIT THUNDER. HIGH PRESSURE
AND DRY AIR ARE EXPECTED TO RETURN FOR TUESDAY AND WEDNESDAY.
TEMPERATURES WILL START OUT A BIT COOL ON SATURDAY WITH HIGHS
FORECAST TO BE IN THE UPPER 50S TO MID 60S. DUE TO A MODEST AMOUNT
OF WARM ADVECTION...HIGHS FOR SUNDAY THROUGH WEDNESDAY ARE
ANTICIPATED TO AVERAGE IN THE NEAR NORMAL MID AND UPPER 60S.
&&
.AVIATION /02Z THURSDAY THROUGH MONDAY/...
WITH HIGH PRESSURE TO THE EAST...AND LOW PRESSURE TO THE
WEST...SOUTHERLY FLOW WILL DEVELOP OVER THE OHIO VALLEY ON
THURSDAY. SOUTHEASTERLY WINDS WILL TURN SOUTH BY LATE MORNING
TOMORROW...WITH WINDS GENERALLY REMAINING IN THE 5-10 KNOT RANGE.
A FEW OCCASIONAL GUSTS UP TO AROUND 15 KNOTS WILL BE POSSIBLE.
WITH A FAIRLY DRY AIR MASS IN PLACE...CLOUDS WILL GENERALLY BE
LIMITED TO PATCHES OF CIRRUS AND CIRROSTRATUS. A FEW CUMULUS
COULD DEVELOP NEAR DAYTON...BUT VFR CONDITIONS ARE EXPECTED
THROUGH THE PERIOD,
OUTLOOK...MVFR CEILINGS AND VISIBILITIES ARE POSSIBLE MONDAY.
&&
.ILN WATCHES/WARNINGS/ADVISORIES...
OH...FROST ADVISORY FROM 2 AM TO 9 AM EDT THURSDAY FOR OHZ077>082-
088.
KY...FROST ADVISORY FROM 2 AM TO 9 AM EDT THURSDAY FOR KYZ089>100.
IN...FROST ADVISORY FROM 2 AM TO 9 AM EDT THURSDAY FOR INZ073>075-
080.
&&
$$
SYNOPSIS...AR
NEAR TERM...HATZOS/AR
SHORT TERM...AR
LONG TERM...CONIGLIO
AVIATION...HATZOS
AREA FORECAST DISCUSSION
NWS GREENVILLE-SPARTANBURG SC
148 PM EDT TUE APR 15 2014
.SYNOPSIS...
A COLD FRONT WILL MOVE OFF THE CAROLINA COAST TONIGHT AS
UNSEASONABLY COLD HIGH PRESSURE BUILDS ACROSS OUR REGION AND REMAINS
INTO FRIDAY. A DEEP UPPER TROUGH ARRIVES FROM THE WEST TO START THE
WEEKEND.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 145 PM EDT MONDAY...A LINE OF SHOWERS AND TSTMS HAS DEVELOPED
AHEAD OF THE SFC COLD FRONT. THIS IS PRETTY MUCH WHAT WAS EXPECTED
AND THE LINE SHOULD MARCH EASTWARD ACROSS THE REST OF THE FORECAST
AREA DURING THE REMAINDER OF THE AFTN.
AS OF 1150 AM EDT MONDAY...BASED ON THE RAPID COOL-OFF OVER THE NC
MTNS...AS WELL AS UPSTREAM SNOW REPORTS...I NOW HAVE SOME MINOR SNOW
ACCUMULATIONS ABOVE 5KFT OVER THE SMOKY MOUNTAINS AND THE NRN NC
MTNS. ALSO ADJUSTED TEMPS AND DEWPOINTS ACROSS THE REGION TO ACCOUNT
FOR THE RAPID TEMPERATURE DROP BEHIND THE FRONT. NO CHANGE ON THE
THINKING IN THE WARM SECTOR. SHOWERS AND A FEW TSTMS SHOULD INCREASE
ALONG AND AHEAD OF THE FRONT...BUT NOT EXPECTING ENOUGH HEATING FOR
A SEVERE THREAT UNTIL THE CONVECTION GETS EAST OF THE FORECAST AREA.
AS OF 1045 AM EDT MONDAY...LITTLE CHANGE FROM THE PREVIOUS UPDATE.
THE SFC COLD FRONT IS SHOWING UP AS A RADAR FINE LINE...AND HAS NOW
MOVED INTO THE WRN UPSTATE...AND ABOUT HALF WAY ACROSS THE NC MTNS.
AS OF 905 AM EDT MONDAY...LOWERED POPS AND CUT BACK THUNDER CHANCES
OVER THE REGION FOR THE NEXT COUPLE HOURS. SPC HAS CUT THE SLIGHT
RISK AREA FROM OUR EASTERN ZONES AND THE LOW OVERCAST THAT IS NOW
DEVELOPING AHEAD OF THE COLD FRONT SHOULD INHIBIT WHAT WAS ALREADY
EXPECTED TO BE LIMITED HEATING. AS THE FRONT MOVES ACROSS THE
FORECAST AREA...I STILL THINK WE WILL SEE AN INCREASE IN SHOWERS AND
FEW TSTMS. THE HRRR AND OUR LOCAL WRF-ARW INDICATE THIS. SO I DID
KEEP HIGHER POPS OVER THE EASTERN ZONES A LITTLE LATER IN THE DAY.
I/M GOING TO START THE WIND ADVISORY OVER THE MOUNTAINS EFFECTIVE
IMMEDIATELY. THE NAM AVL BUFKIT SOUNDING SHOWS A NEARLY 10 DEG C
TEMP DROP FROM 14 TO 15 UTC. THAT KIND OF COLD ADVECTION SHOULD
BRING SOME GOOD GUSTS TO THE MTNS.
AS OF 7 AM...SHRA WILL REMAIN ACROSS THE AREA AS THE COLD FRONT
APPROACHES THIS MORNING. EXPECT PRECIP TO TAPER OFF FROM SW TO NE
THRU THE DAY. SYNOPTIC AND MESOSCALE GUIDANCE SUGGEST A WAVE
DEVELOPING ALONG THE FRONT AND MOVING ACROSS THE CLT AREA AROUND 18Z
WITH FROPA. HAVE KEPT POP HIGH ACROSS THIS AREA THE LONGEST TO COVER
THIS SCENARIO. IF THIS WAVE DOES DEVELOP...SVR STORM CHC WILL
DEVELOP AS THE SHEAR AND HELICITY INCREASE SIGNIFICANTLY. THERE WILL
BE LITTLE IN THE WAY OF INSTABILITY...BUT WHAT THERE IS WILL BE OVER
THAT AREA. UPDATED TO COVER THESE CONCERNS AND CURRENT CONDITIONS.
AS OF 320 AM...WIDESPREAD SHRA CURRENTLY ACROSS THE AREA WITH SCT
TSRA ACROSS THE I-77 CORRIDOR. WIDESPREAD SHRA SHOULD CONTINUE
ACROSS THE AREA THRU MID MORNING AHEAD OF AN APPROACHING COLD FRONT.
THE FIRST WAVE OF TSRA WILL MOVE EAST OF THE AREA BY DAYBREAK. THE
BIG QUESTION IS HOW MUCH...IF ANY...ADDITIONAL TSRA DEVELOP AS THE
FRONT MOVES THRU. FCST SOUNDINGS SHOW LITTLE TO NO INSTABILITY AFTER
DAYBREAK. HOWEVER...THERE WILL BE STRONG FORCING AND UPPER
DIVERGENCE ASSOCIATED WITH THE FRONT. ALSO...GUIDANCE SHOWS A WAVE
FORMING ALONG THE FRONT AND MOVING ACROSS THE SAME LOCATION WHERE
TSRA ARE CURRENTLY. ALTHOUGH NO LIGHTNING IS CURRENTLY ASSOCIATED
WITH THIS FEATURE...A SWIRL IS SEEN MOVING THIS WAY...AND WOULD
REACH THE I-77 CORRIDOR BY OR SHORTLY AFTER DAYBREAK. THEREFORE...
WILL KEEP CAT POPS ACROSS THE AREA THRU 12Z...THEN TAPER OFF POP
FROM SW TO NE THRU THE MORNING...WITH LINGERING CAT POP OVER THE
I-77 CORRIDOR THRU 18Z. WILL KEEP ISOLATED TO SCT TSRA ACROSS THE
ARE WITH BEST CHC ALONG AND SOUTH OF THE I-85 CORRIDOR AND ALONG AND
EAST OF THE I-77 CORRIDOR. WITH THE HIGH SHEAR AND LOW CAPE
ENVIRONMENT REMAINING IN PLACE...WILL HAVE TO WATCH ANY LINEAR STORM
FEATURES THAT DEVELOP FOR THE POSSIBILITY OF DAMAGING WIND GUSTS.
THAT SAID...BEST CHC OF ANY SEVERE STORMS WILL BE EAST AND SOUTH OF
OUR CWFA. THERE WILL BE QUITE A BIT OF ADDITIONAL RAINFALL ACROSS
THE AREA THIS MORNING...SO WILL HAVE TO KEEP AN EYE ON STREAM
LEVELS. ISOLATED FLOODING IS POSSIBLE...AND COULD BE LIMITED TO
MAINLY MORE URBANIZED LOCATIONS. WINDS WILL INCREASE AND BECOME
QUITE GUSTY BEHIND THE COLD FRONT THIS AFTERNOON. WIND GUSTS SHUD
REACH ADVISORY CRITERION ACROSS THE MTNS OF THE CAROLINAS AND NE GA.
WILL ISSUE A WIND ADVISORY FOR THESE LOCATIONS FROM 2 PM THRU
MIDNIGHT.
PRECIP TAPERS OFF QUICKLY THIS EVENING...BUT LINGERING MOISTURE IN
THE NW FLOW AND CAA COULD LEAD TO RAIN SHOWERS CHANGING TO SNOW
SHOWERS BEFORE ENDING BY MIDNIGHT. ANY SNOW WOULD BE LIGHT WITH NO
ACCUMS. ELSEHWERE...DIMINISHING WINDS AND CLEARING SKIES EXPECTED.
WITH THE VERY COLD AIR MASS MOVING IN...AN ADVECTIVE FREEZE IS
EXPECTED ACROSS MOST OF THE CWFA. WILL UPGRADE THE WATCH TO A
WARNING FOR ALL BUT THE NRN MTNS WHICH HAVE NOT REACHED THE
CLIMATOLOGICAL GROWING SEASON YET. LOWS WILL BE 15 TO NEARLY 20
DEGREES BELOW NORMAL...AND WILL THREATEN RECORDS AT AVL AND CLT. THE
RECORD AT GSP IS QUITE COLD AND SHOULD BE SAFE.
&&
.SHORT TERM /WEDNESDAY THROUGH THURSDAY/...
AS OF 210 PM TUESDAY...A DRY AND COOL ARIMASS WILL DOMINATE THE
WEATHER THROUGH THURSDAY. AT THE SURFACE...A CP HIGH CENTERED OVER NEW
ENGLAND WILL SLOWLY MOVE NORTHEAST...WITH A DRY WEDGE REMAINING
ALONG THE EAST SLOPES OF THE APPALACHIANS. 12Z MODELS CONTINUE TO
SHOW AN INCREASE IN MOISTURE ON FRI AS A SHORT WAVE TROUGH
APPROACHES FROM THE WEST AND WINDS VEER TO A MORE EASTERLY/UPSLOPE
COMPONENT. ALSO...CYCLOGENESIS IS STILL EXPECTED ALONG THE OLD
FRONTAL ZONE OVER THE CENTRAL GULF AS THE UPPER WAVE APPROACHES.
HOWEVER...WILL DISCOUNT THE CMH SOLUTION OF A MORE NORTHERN
DEVELOPMENT OF THE LOW AND SIGNIFICANT QPF EXTENDING NORTH INTO THE
AREA AND ACCEPT THE IDEA OF THE GFS/ECM THAT THE ASSOCIATED QPF WILL
STAY WELL SOUTH OF THE AREA. THEREFORE EXPECT QPFTO BE MINIMAL OR
NON-EXISTANT. WILL HAVE SOME VERY LOW END POPS OVER THE MOUNTAINS
WHERE UPSLOPE FLOW COULD SQUEEZE OUT SOME SPRINKLES. THIS IDEA IS
SUPPORTED BY THE NAM/SREF.
THE HIGHEST IMPACT WEATHER THROUGH THE SHORT TERM WILL BE THE COLD
TEMPS AGAIN WED NIGHT. WITH VERY FAVORABLE RADIATIONAL COOLING
CONDITIONS ALONG WITH THE DRY AIRMASS...FROST/FREEZE CONDITIONS ARE
EXPECTED EARLY THU. FREEZING TEMPS ARE A GOOD BET ACROSS ALL OF THE
MOUNTAINS/FOOTHILLS AND PORTIONS OF THE PIEDMONT. WILL BE POSTING A
FREEZE WATCH FOR MOST OF THE AREA FOR WED NIGHT. ALSO...SOME SCT
FROST CAN`T BE RULED OUT EARLY FRI OVER NORTHERN AREAS.
&&
.LONG TERM /THURSDAY NIGHT THROUGH MONDAY/...
AS OF 340 AM TUESDAY...MEDIUM RANGE GUIDANCE INDICATES THAT A H5
TROF AXIS WILL SLOWLY RIPPLE ACROSS THE SOUTHEAST LATE THIS WEEK.
THE PASSAGE OF THE TROUGH MAY RESULT IN A PERIOD OF UNSETTLED
WEATHER FOR FRIDAY AND SATURDAY. HOWEVER...BOTH THE GFS AND ECMWF
INDICATE THAT A LOW MAY DEVELOP OFF THE SOUTHEAST COAST LATE FRIDAY
AND SATURDAY...WITH A SECOND AREA OF LOW PRESSURE ACROSS THE UPPER
OHIO RIVER VALLEY. COVERAGE OF QPF ACROSS THE CWFA REMAINS VERY
LIMITED BETWEEN THE TWO SYSTEMS. I WILL MAINTAIN SCHC TO CHC POPS
FOR SHRA BETWEEN FRI TO SAT. SUN...MID LEVEL SHALLOW RIDGING WILL
BUILD ACROSS THE REGION...WITH WEAK WAA. TEMPERATURES ARE FORECAST
TO RETURN TO AROUND NORMAL VALUES. ON MON...A SOUTHERN STREAM LOW
MAY DEVELOP AHEAD OF MID LEVEL SHORTWAVE ACROSS THE DEEP SOUTH.
MOISTURE AND LIFT ASSOCIATED WITH THE LOW MAY SUPPORT A FEW SHRA MON
AFTERNOON.
&&
.AVIATION /18Z TUESDAY THROUGH SUNDAY/...
AT KCLT...A LINE OF SHOWERS AND TSTMS WILL CROSS THE AIRFIELD
BETWEEN 18-20 UTC. EXPECT GUSTY AND ERRATIC WINDS AND VERY HEAVY
RAIN AS THE LINE PASSES. WINDS WILL SHIFT TO THE NORTHWEST BEHIND
THE LINE AS A COLD FRONT CROSSES THE AIRFIELD. MVFR CIGS ARE
EXPECTED TO PERSIST FOR A COUPLE HOURS AFTER THE FRONTAL PASSAGE.
WINDS WILL GUST UP TO 28-30 KTS INTO THE EVENING HOURS. LATER
TONIGHT THE WINDS WILL VEER TO THE NORTHEAST AS HIGH PRESSURE MOVES
INTO THE MID-ATLANTIC STATES.
ELSEWHERE...A COLD FRONT WITH ASSOCIATED SHRA/TSTMS WAS CROSSING THE
AIRFIELDS AT KGSP/KGMU AT ISSUANCE TIME. WINDS WILL SHIFT TO THE
NORTHWEST BEHIND THE LINE OF STORMS...THOUGH SCT SHOWERS AND MVFR
CIGS AREA EXPECTED TO PERSIST FOR A COUPLE HOURS BEHIND THE FRONT.
WINDS MAY GUST AS HIGH AS 30 KTS INTO THE EVENING HOURS. WINDS AT
KAVL WILL BE STRONGER...GUSTING ALMOST TO 40KTS FROM THE NW INTO THE
EVENING HOURS.
OUTLOOK...HIGH PRESSURE WILL PRODUCE VFR WEATHER WEDNESDAY AND
THURSDAY. CEILING AND VISIBILITY RESTRICTIONS WILL RETURN FRIDAY AND
SATURDAY AS A COLD FRONT APPROACHES FROM THE WEST AND A LOW PRESSURE
SYSTEM DEVELOPS ALONG THE COAST.
CONFIDENCE TABLE...
17-23Z 23-05Z 05-11Z 11-17Z
KCLT HIGH 87% HIGH 100% HIGH 100% HIGH 100%
KGSP HIGH 93% HIGH 100% HIGH 100% HIGH 100%
KAVL HIGH 95% HIGH 100% HIGH 100% HIGH 100%
KHKY HIGH 96% HIGH 100% HIGH 100% HIGH 100%
KGMU HIGH 93% HIGH 100% HIGH 100% HIGH 100%
KAND HIGH 93% HIGH 100% 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
&&
.CLIMATE...
RECORD LOWS FOR WEDNESDAY APRIL 16...
AVL...26 IN 1943
CLT...29 IN 2008
GSP...24 IN 1907
&&
.GSP WATCHES/WARNINGS/ADVISORIES...
GA...FREEZE WARNING FROM 11 PM THIS EVENING TO 10 AM EDT WEDNESDAY
FOR GAZ010-017-018-026-028-029.
WIND ADVISORY UNTIL MIDNIGHT EDT TONIGHT FOR GAZ010-017.
NC...FREEZE WARNING FROM 11 PM THIS EVENING TO 10 AM EDT WEDNESDAY
FOR NCZ035>037-048-051>053-056>059-062>065-068>072-082-
501>510.
WIND ADVISORY UNTIL MIDNIGHT EDT TONIGHT FOR NCZ033-048>053-
058-059-062>065-501-503-505-507-509.
SC...FREEZE WARNING FROM 11 PM THIS EVENING TO 10 AM EDT WEDNESDAY
FOR SCZ001>014-019.
WIND ADVISORY UNTIL MIDNIGHT EDT TONIGHT FOR SCZ001>003.
&&
$$
SYNOPSIS...NED
NEAR TERM...MCAVOY
SHORT TERM...NED
LONG TERM...NED
AVIATION...MCAVOY
CLIMATE...
AREA FORECAST DISCUSSION
NWS GREENVILLE-SPARTANBURG SC
1153 AM EDT TUE APR 15 2014
.SYNOPSIS...
A COLD FRONT WILL CROSS THE THE PIEDMONT AROUND MID DAY.
UNSEASONABLY COLD HIGH PRESSURE WILL BE IN CONTROL OF OUR WEATHER
FROM TONIGHT INTO FRIDAY. A DEEP UPPER TROUGH ARRIVES FROM THE WEST
TO START THE WEEKEND.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 1150 AM EDT MONDAY...BASED ON THE RAPID COOL-OFF OVER THE NC
MTNS...AS WELL AS UPSTREAM SNOW REPORTS...I NOW HAVE SOME MINOR SNOW
ACCUMULATIONS ABOVE 5KFT OVER THE SMOKY MOUNTAINS AND THE NRN NC
MTNS. ALSO ADJUSTED TEMPS AND DEWPOINTS ACROSS THE REGION TO ACCOUNT
FOR THE RAPID TEMPERATURE DROP BEHIND THE FRONT. NO CHANGE ON THE
THINKING IN THE WARM SECTOR. SHOWERS AND A FEW TSTMS SHOULD INCREASE
ALONG AND AHEAD OF THE FRONT...BUT NOT EXPECTING ENOUGH HEATING FOR
A SEVERE THREAT UNTIL THE CONVECTION GETS EAST OF THE FORECAST AREA.
AS OF 1045 AM EDT MONDAY...LITTLE CHANGE FROM THE PREVIOUS UPDATE.
THE SFC COLD FRONT IS SHOWING UP AS A RADAR FINE LINE...AND HAS NOW
MOVED INTO THE WRN UPSTATE...AND ABOUT HALF WAY ACROSS THE NC MTNS.
AS OF 905 AM EDT MONDAY...LOWERED POPS AND CUT BACK THUNDER CHANCES
OVER THE REGION FOR THE NEXT COUPLE HOURS. SPC HAS CUT THE SLIGHT
RISK AREA FROM OUR EASTERN ZONES AND THE LOW OVERCAST THAT IS NOW
DEVELOPING AHEAD OF THE COLD FRONT SHOULD INHIBIT WHAT WAS ALREADY
EXPECTED TO BE LIMITED HEATING. AS THE FRONT MOVES ACROSS THE
FORECAST AREA...I STILL THINK WE WILL SEE AN INCREASE IN SHOWERS AND
FEW TSTMS. THE HRRR AND OUR LOCAL WRF-ARW INDICATE THIS. SO I DID
KEEP HIGHER POPS OVER THE EASTERN ZONES A LITTLE LATER IN THE DAY.
I/M GOING TO START THE WIND ADVISORY OVER THE MOUNTAINS EFFECTIVE
IMMEDIATELY. THE NAM AVL BUFKIT SOUNDING SHOWS A NEARLY 10 DEG C
TEMP DROP FROM 14 TO 15 UTC. THAT KIND OF COLD ADVECTION SHOULD
BRING SOME GOOD GUSTS TO THE MTNS.
AS OF 7 AM...SHRA WILL REMAIN ACROSS THE AREA AS THE COLD FRONT
APPROACHES THIS MORNING. EXPECT PRECIP TO TAPER OFF FROM SW TO NE
THRU THE DAY. SYNOPTIC AND MESOSCALE GUIDANCE SUGGEST A WAVE
DEVELOPING ALONG THE FRONT AND MOVING ACROSS THE CLT AREA AROUND 18Z
WITH FROPA. HAVE KEPT POP HIGH ACROSS THIS AREA THE LONGEST TO COVER
THIS SCENARIO. IF THIS WAVE DOES DEVELOP...SVR STORM CHC WILL
DEVELOP AS THE SHEAR AND HELICITY INCREASE SIGNIFICANTLY. THERE WILL
BE LITTLE IN THE WAY OF INSTABILITY...BUT WHAT THERE IS WILL BE OVER
THAT AREA. UPDATED TO COVER THESE CONCERNS AND CURRENT CONDITIONS.
AS OF 320 AM...WIDESPREAD SHRA CURRENTLY ACROSS THE AREA WITH SCT
TSRA ACROSS THE I-77 CORRIDOR. WIDESPREAD SHRA SHOULD CONTINUE
ACROSS THE AREA THRU MID MORNING AHEAD OF AN APPROACHING COLD FRONT.
THE FIRST WAVE OF TSRA WILL MOVE EAST OF THE AREA BY DAYBREAK. THE
BIG QUESTION IS HOW MUCH...IF ANY...ADDITIONAL TSRA DEVELOP AS THE
FRONT MOVES THRU. FCST SOUNDINGS SHOW LITTLE TO NO INSTABILITY AFTER
DAYBREAK. HOWEVER...THERE WILL BE STRONG FORCING AND UPPER
DIVERGENCE ASSOCIATED WITH THE FRONT. ALSO...GUIDANCE SHOWS A WAVE
FORMING ALONG THE FRONT AND MOVING ACROSS THE SAME LOCATION WHERE
TSRA ARE CURRENTLY. ALTHOUGH NO LIGHTNING IS CURRENTLY ASSOCIATED
WITH THIS FEATURE...A SWIRL IS SEEN MOVING THIS WAY...AND WOULD
REACH THE I-77 CORRIDOR BY OR SHORTLY AFTER DAYBREAK. THEREFORE...
WILL KEEP CAT POPS ACROSS THE AREA THRU 12Z...THEN TAPER OFF POP
FROM SW TO NE THRU THE MORNING...WITH LINGERING CAT POP OVER THE
I-77 CORRIDOR THRU 18Z. WILL KEEP ISOLATED TO SCT TSRA ACROSS THE
ARE WITH BEST CHC ALONG AND SOUTH OF THE I-85 CORRIDOR AND ALONG AND
EAST OF THE I-77 CORRIDOR. WITH THE HIGH SHEAR AND LOW CAPE
ENVIRONMENT REMAINING IN PLACE...WILL HAVE TO WATCH ANY LINEAR STORM
FEATURES THAT DEVELOP FOR THE POSSIBILITY OF DAMAGING WIND GUSTS.
THAT SAID...BEST CHC OF ANY SEVERE STORMS WILL BE EAST AND SOUTH OF
OUR CWFA. THERE WILL BE QUITE A BIT OF ADDITIONAL RAINFALL ACROSS
THE AREA THIS MORNING...SO WILL HAVE TO KEEP AN EYE ON STREAM
LEVELS. ISOLATED FLOODING IS POSSIBLE...AND COULD BE LIMITED TO
MAINLY MORE URBANIZED LOCATIONS. WINDS WILL INCREASE AND BECOME
QUITE GUSTY BEHIND THE COLD FRONT THIS AFTERNOON. WIND GUSTS SHUD
REACH ADVISORY CRITERION ACROSS THE MTNS OF THE CAROLINAS AND NE GA.
WILL ISSUE A WIND ADVISORY FOR THESE LOCATIONS FROM 2 PM THRU
MIDNIGHT.
PRECIP TAPERS OFF QUICKLY THIS EVENING...BUT LINGERING MOISTURE IN
THE NW FLOW AND CAA COULD LEAD TO RAIN SHOWERS CHANGING TO SNOW
SHOWERS BEFORE ENDING BY MIDNIGHT. ANY SNOW WOULD BE LIGHT WITH NO
ACCUMS. ELSEHWERE...DIMINISHING WINDS AND CLEARING SKIES EXPECTED.
WITH THE VERY COLD AIR MASS MOVING IN...AN ADVECTIVE FREEZE IS
EXPECTED ACROSS MOST OF THE CWFA. WILL UPGRADE THE WATCH TO A
WARNING FOR ALL BUT THE NRN MTNS WHICH HAVE NOT REACHED THE
CLIMATOLOGICAL GROWING SEASON YET. LOWS WILL BE 15 TO NEARLY 20
DEGREES BELOW NORMAL...AND WILL THREATEN RECORDS AT AVL AND CLT. THE
RECORD AT GSP IS QUITE COLD AND SHOULD BE SAFE.
&&
.SHORT TERM /WEDNESDAY THROUGH THURSDAY/...
AS OF 310 AM TUESDAY...ON WEDNESDAY...THE CENTER OF SFC HIGH
PRESSURE IS EXPECTED TO BE CENTERED OVER THE MID APPALACHIANS AROUND
SUNRISE. THE HIGH CENTER WILL REACH NEW ENGLAND BY 0Z THURSDAY...BUT
WILL CONTINUE TO RIDGE ACROSS THE SOUTHEAST. STRONG INSOLATION
SHOULD RESULT IN GRADUAL WARMING...BUT LLVL THICKNESSES AND
TEMPERATURES WILL REMAIN UNSEASONABLE COOL. A BLEND OF PREFERRED MOS
SUPPORTS HIGH TEMPERATURES RANGING FROM THE MID 50S ACROSS THE MTN
VALLEYS TO NEAR 60 ACROSS THE UPPER SAVANNAH RIVER VALLEY. FORECAST
SOUNDINGS INDICATE THAT AFTERNOON MIXING MAY REACH AROUND 3
KFT...WITH PW VALUES AROUND 0.20 INCHES. AFTERNOON DEWPOINTS MAY MIX
TO THE TEENS...RESULTING IN RH VALUES AROUND 20 PERCENT.
WEDNESDAY NIGHT...A DRY AND COOL AIR MASS WILL REMAIN RIDGED ACROSS
THE CWFA. LIGHT NE WINDS AND CLEAR SKY CONDITIONS SHOULD RESULT IN
FAVORABLE RADIATIONAL COOLING CONDITIONS. LOW TEMPERATURES ARE
EXPECTED TO RANGE FROM U20S TO NEAR 30 ACROSS THE NC
MTNS...FOOTHILLS...AND PIEDMONT. LOW TEMPERATURES ACROSS THE UPSTATE
AND NE GA MAY RANGE IN THE LOW TO MID 30S. ON THURSDAY...SHORT RANGE
MODELS INDICATE THAT H85 TEMPERATURES WILL WARM 2-4 DEGREES FROM
WED. HIGH TEMPERATURES ON THURSDAY SHOULD WARM AROUND 3 DEGREES
WARMER THAN VALUES OBSERVED ON WED.
&&
.LONG TERM /THURSDAY NIGHT THROUGH MONDAY/...
AS OF 340 AM TUESDAY...MEDIUM RANGE GUIDANCE INDICATES THAT A H5
TROF AXIS WILL SLOWLY RIPPLE ACROSS THE SOUTHEAST LATE THIS WEEK.
THE PASSAGE OF THE TROUGH MAY RESULT IN A PERIOD OF UNSETTLED
WEATHER FOR FRIDAY AND SATURDAY. HOWEVER...BOTH THE GFS AND ECMWF
INDICATE THAT A LOW MAY DEVELOP OFF THE SOUTHEAST COAST LATE FRIDAY
AND SATURDAY...WITH A SECOND AREA OF LOW PRESSURE ACROSS THE UPPER
OHIO RIVER VALLEY. COVERAGE OF QPF ACROSS THE CWFA REMAINS VERY
LIMITED BETWEEN THE TWO SYSTEMS. I WILL MAINTAIN SCHC TO CHC POPS
FOR SHRA BETWEEN FRI TO SAT. SUN...MID LEVEL SHALLOW RIDGING WILL
BUILD ACROSS THE REGION...WITH WEAK WAA. TEMPERATURES ARE FORECAST
TO RETURN TO AROUND NORMAL VALUES. ON MON...A SOUTHERN STREAM LOW
MAY DEVELOP AHEAD OF MID LEVEL SHORTWAVE ACROSS THE DEEP SOUTH.
MOISTURE AND LIFT ASSOCIATED WITH THE LOW MAY SUPPORT A FEW SHRA MON
AFTERNOON.
&&
.AVIATION /16Z TUESDAY THROUGH SATURDAY/...
AT KCLT...LOW CLOUDS HAVE DISSIPATED AS HEAVY RAIN HAS MOVED EAST OF
THE AREA. EXPECT A RETURN TO MVFR LATER THIS MORNING AHEAD OF A COLD
FRONT MOVING INTO THE AREA...ALONG WITH CONTINUED SHRA. THERE IS A
CHANCE THAT IFR CIGS WILL DEVELOP OVER THE NEXT COUPLE
HOURS...THOUGH CONFIDENCE ISN/T HIGH ENOUGH TO INCLUDE THAT AT THIS
TIME. THE CHC FOR TSRA LOOKS TO BE AROUND 18Z NEAR THE TIME OF
FROPA. HAVE MADE THE WIND SHIFT TO NW AT THAT TIME AS WELL. GUSTY NW
WINDS WITH CLEARING SKIES THRU THE AFTERNOON. GUSTS CONTINUE INTO
THRU MUCH OF THE NITE WITH WINDS TURNING NLY AND GUSTS DIMINISHING
TOWARD DAYBREAK.
ELSEWHERE...SIMILAR CONDITIONS TO KCLT...EXCEPT EARLIER
ONSET...FROPA AND IMPROVEMENT. TSRA CHC MUCH LESS AT THESE
LOCATIONS...SO HAVE LEFT OUT FOR NOW. VERY GUSTY WINDS EXPECTED ALL
LOCATIONS AS WELL. KAND WILL SEE MORE WLY WIND THAN NW. KAVL MAY SEE
SOME LINGERING LOW VFR CLOUDS DURING THE AFTERNOON AND EVENING.
OUTLOOK...HIGH PRESSURE WILL PRODUCE VFR WEATHER WEDNESDAY AND
THURSDAY. CEILING AND VISIBILITY RESTRICTIONS WILL RETURN FRIDAY AND
SATURDAY AS A COLD FRONT APPROACHES FROM THE WEST AND A LOW PRESSURE
SYSTEM DEVELOPS ALONG THE COAST.
CONFIDENCE TABLE...
16-22Z 22-04Z 04-10Z 10-16Z
KCLT HIGH 95% HIGH 100% HIGH 100% HIGH 100%
KGSP HIGH 90% HIGH 100% HIGH 100% HIGH 100%
KAVL HIGH 83% HIGH 100% HIGH 100% HIGH 100%
KHKY HIGH 91% HIGH 100% HIGH 100% HIGH 100%
KGMU HIGH 89% HIGH 100% HIGH 100% HIGH 100%
KAND HIGH 92% HIGH 100% 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
&&
.CLIMATE...
RECORD LOWS FOR WEDNESDAY APRIL 16...
AVL...26 IN 1943
CLT...29 IN 2008
GSP...24 IN 1907
&&
.GSP WATCHES/WARNINGS/ADVISORIES...
GA...FREEZE WARNING FROM 11 PM THIS EVENING TO 10 AM EDT WEDNESDAY
FOR GAZ010-017-018-026-028-029.
WIND ADVISORY UNTIL MIDNIGHT EDT TONIGHT FOR GAZ010-017.
NC...FREEZE WARNING FROM 11 PM THIS EVENING TO 10 AM EDT WEDNESDAY
FOR NCZ035>037-048-051>053-056>059-062>065-068>072-082-
501>510.
WIND ADVISORY UNTIL MIDNIGHT EDT TONIGHT FOR NCZ033-048>053-
058-059-062>065-501-503-505-507-509.
SC...FREEZE WARNING FROM 11 PM THIS EVENING TO 10 AM EDT WEDNESDAY
FOR SCZ001>014-019.
WIND ADVISORY UNTIL MIDNIGHT EDT TONIGHT FOR SCZ001>003.
&&
$$
SYNOPSIS...NED
NEAR TERM...MCAVOY
SHORT TERM...NED
LONG TERM...NED
AVIATION...MCAVOY/RWH
CLIMATE...
AREA FORECAST DISCUSSION
NWS GREENVILLE-SPARTANBURG SC
1044 AM EDT TUE APR 15 2014
.SYNOPSIS...
A COLD FRONT WILL CROSS THE THE PIEDMONT AROUND MID DAY.
UNSEASONABLY COLD HIGH PRESSURE WILL BE IN CONTROL OF OUR WEATHER
FROM TONIGHT INTO FRIDAY. A DEEP UPPER TROUGH ARRIVES FROM THE WEST
TO START THE WEEKEND.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 1045 AM EDT MONDAY...LITTLE CHANGE FROM THE PREVIOUS UPDATE.
THE SFC COLD FRONT IS SHOWING UP AS A RADAR FINE LINE...AND HAS NOW
MOVED INTO THE WRN UPSTATE...AND ABOUT HALF WAY ACROSS THE NC MTNS.
AS OF 905 AM EDT MONDAY...LOWERED POPS AND CUT BACK THUNDER CHANCES
OVER THE REGION FOR THE NEXT COUPLE HOURS. SPC HAS CUT THE SLIGHT
RISK AREA FROM OUR EASTERN ZONES AND THE LOW OVERCAST THAT IS NOW
DEVELOPING AHEAD OF THE COLD FRONT SHOULD INHIBIT WHAT WAS ALREADY
EXPECTED TO BE LIMITED HEATING. AS THE FRONT MOVES ACROSS THE
FORECAST AREA...I STILL THINK WE WILL SEE AN INCREASE IN SHOWERS AND
FEW TSTMS. THE HRRR AND OUR LOCAL WRF-ARW INDICATE THIS. SO I DID
KEEP HIGHER POPS OVER THE EASTERN ZONES A LITTLE LATER IN THE DAY.
I/M GOING TO START THE WIND ADVISORY OVER THE MOUNTAINS EFFECTIVE
IMMEDIATELY. THE NAM AVL BUFKIT SOUNDING SHOWS A NEARLY 10 DEG C
TEMP DROP FROM 14 TO 15 UTC. THAT KIND OF COLD ADVECTION SHOULD
BRING SOME GOOD GUSTS TO THE MTNS.
AS OF 7 AM...SHRA WILL REMAIN ACROSS THE AREA AS THE COLD FRONT
APPROACHES THIS MORNING. EXPECT PRECIP TO TAPER OFF FROM SW TO NE
THRU THE DAY. SYNOPTIC AND MESOSCALE GUIDANCE SUGGEST A WAVE
DEVELOPING ALONG THE FRONT AND MOVING ACROSS THE CLT AREA AROUND 18Z
WITH FROPA. HAVE KEPT POP HIGH ACROSS THIS AREA THE LONGEST TO COVER
THIS SCENARIO. IF THIS WAVE DOES DEVELOP...SVR STORM CHC WILL
DEVELOP AS THE SHEAR AND HELICITY INCREASE SIGNIFICANTLY. THERE WILL
BE LITTLE IN THE WAY OF INSTABILITY...BUT WHAT THERE IS WILL BE OVER
THAT AREA. UPDATED TO COVER THESE CONCERNS AND CURRENT CONDITIONS.
AS OF 320 AM...WIDESPREAD SHRA CURRENTLY ACROSS THE AREA WITH SCT
TSRA ACROSS THE I-77 CORRIDOR. WIDESPREAD SHRA SHOULD CONTINUE
ACROSS THE AREA THRU MID MORNING AHEAD OF AN APPROACHING COLD FRONT.
THE FIRST WAVE OF TSRA WILL MOVE EAST OF THE AREA BY DAYBREAK. THE
BIG QUESTION IS HOW MUCH...IF ANY...ADDITIONAL TSRA DEVELOP AS THE
FRONT MOVES THRU. FCST SOUNDINGS SHOW LITTLE TO NO INSTABILITY AFTER
DAYBREAK. HOWEVER...THERE WILL BE STRONG FORCING AND UPPER
DIVERGENCE ASSOCIATED WITH THE FRONT. ALSO...GUIDANCE SHOWS A WAVE
FORMING ALONG THE FRONT AND MOVING ACROSS THE SAME LOCATION WHERE
TSRA ARE CURRENTLY. ALTHOUGH NO LIGHTNING IS CURRENTLY ASSOCIATED
WITH THIS FEATURE...A SWIRL IS SEEN MOVING THIS WAY...AND WOULD
REACH THE I-77 CORRIDOR BY OR SHORTLY AFTER DAYBREAK. THEREFORE...
WILL KEEP CAT POPS ACROSS THE AREA THRU 12Z...THEN TAPER OFF POP
FROM SW TO NE THRU THE MORNING...WITH LINGERING CAT POP OVER THE
I-77 CORRIDOR THRU 18Z. WILL KEEP ISOLATED TO SCT TSRA ACROSS THE
ARE WITH BEST CHC ALONG AND SOUTH OF THE I-85 CORRIDOR AND ALONG AND
EAST OF THE I-77 CORRIDOR. WITH THE HIGH SHEAR AND LOW CAPE
ENVIRONMENT REMAINING IN PLACE...WILL HAVE TO WATCH ANY LINEAR STORM
FEATURES THAT DEVELOP FOR THE POSSIBILITY OF DAMAGING WIND GUSTS.
THAT SAID...BEST CHC OF ANY SEVERE STORMS WILL BE EAST AND SOUTH OF
OUR CWFA. THERE WILL BE QUITE A BIT OF ADDITIONAL RAINFALL ACROSS
THE AREA THIS MORNING...SO WILL HAVE TO KEEP AN EYE ON STREAM
LEVELS. ISOLATED FLOODING IS POSSIBLE...AND COULD BE LIMITED TO
MAINLY MORE URBANIZED LOCATIONS. WINDS WILL INCREASE AND BECOME
QUITE GUSTY BEHIND THE COLD FRONT THIS AFTERNOON. WIND GUSTS SHUD
REACH ADVISORY CRITERION ACROSS THE MTNS OF THE CAROLINAS AND NE GA.
WILL ISSUE A WIND ADVISORY FOR THESE LOCATIONS FROM 2 PM THRU
MIDNIGHT.
PRECIP TAPERS OFF QUICKLY THIS EVENING...BUT LINGERING MOISTURE IN
THE NW FLOW AND CAA COULD LEAD TO RAIN SHOWERS CHANGING TO SNOW
SHOWERS BEFORE ENDING BY MIDNIGHT. ANY SNOW WOULD BE LIGHT WITH NO
ACCUMS. ELSEHWERE...DIMINISHING WINDS AND CLEARING SKIES EXPECTED.
WITH THE VERY COLD AIR MASS MOVING IN...AN ADVECTIVE FREEZE IS
EXPECTED ACROSS MOST OF THE CWFA. WILL UPGRADE THE WATCH TO A
WARNING FOR ALL BUT THE NRN MTNS WHICH HAVE NOT REACHED THE
CLIMATOLOGICAL GROWING SEASON YET. LOWS WILL BE 15 TO NEARLY 20
DEGREES BELOW NORMAL...AND WILL THREATEN RECORDS AT AVL AND CLT. THE
RECORD AT GSP IS QUITE COLD AND SHOULD BE SAFE.
&&
.SHORT TERM /WEDNESDAY THROUGH THURSDAY/...
AS OF 310 AM TUESDAY...ON WEDNESDAY...THE CENTER OF SFC HIGH
PRESSURE IS EXPECTED TO BE CENTERED OVER THE MID APPALACHIANS AROUND
SUNRISE. THE HIGH CENTER WILL REACH NEW ENGLAND BY 0Z THURSDAY...BUT
WILL CONTINUE TO RIDGE ACROSS THE SOUTHEAST. STRONG INSOLATION
SHOULD RESULT IN GRADUAL WARMING...BUT LLVL THICKNESSES AND
TEMPERATURES WILL REMAIN UNSEASONABLE COOL. A BLEND OF PREFERRED MOS
SUPPORTS HIGH TEMPERATURES RANGING FROM THE MID 50S ACROSS THE MTN
VALLEYS TO NEAR 60 ACROSS THE UPPER SAVANNAH RIVER VALLEY. FORECAST
SOUNDINGS INDICATE THAT AFTERNOON MIXING MAY REACH AROUND 3
KFT...WITH PW VALUES AROUND 0.20 INCHES. AFTERNOON DEWPOINTS MAY MIX
TO THE TEENS...RESULTING IN RH VALUES AROUND 20 PERCENT.
WEDNESDAY NIGHT...A DRY AND COOL AIR MASS WILL REMAIN RIDGED ACROSS
THE CWFA. LIGHT NE WINDS AND CLEAR SKY CONDITIONS SHOULD RESULT IN
FAVORABLE RADIATIONAL COOLING CONDITIONS. LOW TEMPERATURES ARE
EXPECTED TO RANGE FROM U20S TO NEAR 30 ACROSS THE NC
MTNS...FOOTHILLS...AND PIEDMONT. LOW TEMPERATURES ACROSS THE UPSTATE
AND NE GA MAY RANGE IN THE LOW TO MID 30S. ON THURSDAY...SHORT RANGE
MODELS INDICATE THAT H85 TEMPERATURES WILL WARM 2-4 DEGREES FROM
WED. HIGH TEMPERATURES ON THURSDAY SHOULD WARM AROUND 3 DEGREES
WARMER THAN VALUES OBSERVED ON WED.
&&
.LONG TERM /THURSDAY NIGHT THROUGH MONDAY/...
AS OF 340 AM TUESDAY...MEDIUM RANGE GUIDANCE INDICATES THAT A H5
TROF AXIS WILL SLOWLY RIPPLE ACROSS THE SOUTHEAST LATE THIS WEEK.
THE PASSAGE OF THE TROUGH MAY RESULT IN A PERIOD OF UNSETTLED
WEATHER FOR FRIDAY AND SATURDAY. HOWEVER...BOTH THE GFS AND ECMWF
INDICATE THAT A LOW MAY DEVELOP OFF THE SOUTHEAST COAST LATE FRIDAY
AND SATURDAY...WITH A SECOND AREA OF LOW PRESSURE ACROSS THE UPPER
OHIO RIVER VALLEY. COVERAGE OF QPF ACROSS THE CWFA REMAINS VERY
LIMITED BETWEEN THE TWO SYSTEMS. I WILL MAINTAIN SCHC TO CHC POPS
FOR SHRA BETWEEN FRI TO SAT. SUN...MID LEVEL SHALLOW RIDGING WILL
BUILD ACROSS THE REGION...WITH WEAK WAA. TEMPERATURES ARE FORECAST
TO RETURN TO AROUND NORMAL VALUES. ON MON...A SOUTHERN STREAM LOW
MAY DEVELOP AHEAD OF MID LEVEL SHORTWAVE ACROSS THE DEEP SOUTH.
MOISTURE AND LIFT ASSOCIATED WITH THE LOW MAY SUPPORT A FEW SHRA MON
AFTERNOON.
&&
.AVIATION /15Z TUESDAY THROUGH SATURDAY/...
AT KCLT...LOW CLOUDS HAVE DISSIPATED AS HEAVY RAIN HAS MOVED EAST OF
THE AREA. EXPECT A RETURN TO MVFR LATER THIS MORNING AHEAD OF A COLD
FRONT MOVING INTO THE AREA...ALONG WITH CONTINUED SHRA. THERE IS A
CHANCE THAT IFR CIGS WILL DEVELOP OVER THE NEXT COUPLE
HOURS...THOUGH CONFIDENCE ISN/T HIGH ENOUGH TO INCLUDE THAT AT THIS
TIME. THE CHC FOR TSRA LOOKS TO BE AROUND 18Z NEAR THE TIME OF
FROPA. HAVE MADE THE WIND SHIFT TO NW AT THAT TIME AS WELL. GUSTY NW
WINDS WITH CLEARING SKIES THRU THE AFTERNOON. GUSTS CONTINUE INTO
THRU MUCH OF THE NITE WITH WINDS TURNING NLY AND GUSTS DIMINISHING
TOWARD DAYBREAK.
ELSEWHERE...SIMILAR CONDITIONS TO KCLT...EXCEPT EARLIER
ONSET...FROPA AND IMPROVEMENT. TSRA CHC MUCH LESS AT THESE
LOCATIONS...SO HAVE LEFT OUT FOR NOW. VERY GUSTY WINDS EXPECTED ALL
LOCATIONS AS WELL. KAND WILL SEE MORE WLY WIND THAN NW. KAVL MAY SEE
SOME LINGERING LOW VFR CLOUDS DURING THE AFTERNOON AND EVENING.
OUTLOOK...HIGH PRESSURE WILL PRODUCE VFR WEATHER WEDNESDAY AND
THURSDAY. CEILING AND VISIBILITY RESTRICTIONS WILL RETURN FRIDAY AND
SATURDAY AS A COLD FRONT APPROACHES FROM THE WEST AND A LOW PRESSURE
SYSTEM DEVELOPS ALONG THE COAST.
CONFIDENCE TABLE...
14-20Z 20-02Z 02-08Z 08-14Z
KCLT HIGH 93% HIGH 94% HIGH 100% HIGH 100%
KGSP HIGH 90% HIGH 100% HIGH 100% HIGH 100%
KAVL HIGH 84% HIGH 100% HIGH 100% HIGH 100%
KHKY HIGH 88% HIGH 100% HIGH 100% HIGH 100%
KGMU HIGH 89% HIGH 100% HIGH 100% HIGH 100%
KAND HIGH 92% HIGH 100% 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
&&
.CLIMATE...
RECORD LOWS FOR WEDNESDAY APRIL 16...
AVL...26 IN 1943
CLT...29 IN 2008
GSP...24 IN 1907
&&
.GSP WATCHES/WARNINGS/ADVISORIES...
GA...FREEZE WARNING FROM 11 PM THIS EVENING TO 10 AM EDT WEDNESDAY
FOR GAZ010-017-018-026-028-029.
WIND ADVISORY UNTIL MIDNIGHT EDT TONIGHT FOR GAZ010-017.
NC...FREEZE WARNING FROM 11 PM THIS EVENING TO 10 AM EDT WEDNESDAY
FOR NCZ035>037-048-051>053-056>059-062>065-068>072-082-
501>510.
WIND ADVISORY UNTIL MIDNIGHT EDT TONIGHT FOR NCZ033-048>053-
058-059-062>065-501-503-505-507-509.
SC...FREEZE WARNING FROM 11 PM THIS EVENING TO 10 AM EDT WEDNESDAY
FOR SCZ001>014-019.
WIND ADVISORY UNTIL MIDNIGHT EDT TONIGHT FOR SCZ001>003.
&&
$$
SYNOPSIS...NED
NEAR TERM...MCAVOY
SHORT TERM...NED
LONG TERM...NED
AVIATION...MCAVOY/RWH
CLIMATE...
AREA FORECAST DISCUSSION
NWS GREENVILLE-SPARTANBURG SC
912 AM EDT TUE APR 15 2014
.SYNOPSIS...
A COLD FRONT WILL CROSS THE THE PIEDMONT AROUND MID DAY.
UNSEASONABLY COLD HIGH PRESSURE WILL BE IN CONTROL OF OUR WEATHER
FROM TONIGHT INTO FRIDAY. A DEEP UPPER TROUGH ARRIVES FROM THE WEST
TO START THE WEEKEND.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 905 AM EDT MONDAY...LOWERED POPS AND CUT BACK THUNDER CHANCES
OVER THE REGION FOR THE NEXT COUPLE HOURS. SPC HAS CUT THE SLIGHT
RISK AREA FROM OUR EASTERN ZONES AND THE LOW OVERCAST THAT IS NOW
DEVELOPING AHEAD OF THE COLD FRONT SHOULD INHIBIT WHAT WAS ALREADY
EXPECTED TO BE LIMITED HEATING. AS THE FRONT MOVES ACROSS THE
FORECAST AREA...I STILL THINK WE WILL SEE AN INCREASE IN SHOWERS AND
FEW TSTMS. THE HRRR AND OUR LOCAL WRF-ARW INDICATE THIS. SO I DID
KEEP HIGHER POPS OVER THE EASTERN ZONES A LITTLE LATER IN THE DAY.
I/M GOING TO START THE WIND ADVISORY OVER THE MOUNTAINS EFFECTIVE
IMMEDIATELY. THE NAM AVL BUFKIT SOUNDING SHOWS A NEARLY 10 DEG C
TEMP DROP FROM 14 TO 15 UTC. THAT KIND OF COLD ADVECTION SHOULD
BRING SOME GOOD GUSTS TO THE MTNS.
AS OF 7 AM...SHRA WILL REMAIN ACROSS THE AREA AS THE COLD FRONT
APPROACHES THIS MORNING. EXPECT PRECIP TO TAPER OFF FROM SW TO NE
THRU THE DAY. SYNOPTIC AND MESOSCALE GUIDANCE SUGGEST A WAVE
DEVELOPING ALONG THE FRONT AND MOVING ACROSS THE CLT AREA AROUND 18Z
WITH FROPA. HAVE KEPT POP HIGH ACROSS THIS AREA THE LONGEST TO COVER
THIS SCENARIO. IF THIS WAVE DOES DEVELOP...SVR STORM CHC WILL
DEVELOP AS THE SHEAR AND HELICITY INCREASE SIGNIFICANTLY. THERE WILL
BE LITTLE IN THE WAY OF INSTABILITY...BUT WHAT THERE IS WILL BE OVER
THAT AREA. UPDATED TO COVER THESE CONCERNS AND CURRENT CONDITIONS.
AS OF 320 AM...WIDESPREAD SHRA CURRENTLY ACROSS THE AREA WITH SCT
TSRA ACROSS THE I-77 CORRIDOR. WIDESPREAD SHRA SHOULD CONTINUE
ACROSS THE AREA THRU MID MORNING AHEAD OF AN APPROACHING COLD FRONT.
THE FIRST WAVE OF TSRA WILL MOVE EAST OF THE AREA BY DAYBREAK. THE
BIG QUESTION IS HOW MUCH...IF ANY...ADDITIONAL TSRA DEVELOP AS THE
FRONT MOVES THRU. FCST SOUNDINGS SHOW LITTLE TO NO INSTABILITY AFTER
DAYBREAK. HOWEVER...THERE WILL BE STRONG FORCING AND UPPER
DIVERGENCE ASSOCIATED WITH THE FRONT. ALSO...GUIDANCE SHOWS A WAVE
FORMING ALONG THE FRONT AND MOVING ACROSS THE SAME LOCATION WHERE
TSRA ARE CURRENTLY. ALTHOUGH NO LIGHTNING IS CURRENTLY ASSOCIATED
WITH THIS FEATURE...A SWIRL IS SEEN MOVING THIS WAY...AND WOULD
REACH THE I-77 CORRIDOR BY OR SHORTLY AFTER DAYBREAK. THEREFORE...
WILL KEEP CAT POPS ACROSS THE AREA THRU 12Z...THEN TAPER OFF POP
FROM SW TO NE THRU THE MORNING...WITH LINGERING CAT POP OVER THE
I-77 CORRIDOR THRU 18Z. WILL KEEP ISOLATED TO SCT TSRA ACROSS THE
ARE WITH BEST CHC ALONG AND SOUTH OF THE I-85 CORRIDOR AND ALONG AND
EAST OF THE I-77 CORRIDOR. WITH THE HIGH SHEAR AND LOW CAPE
ENVIRONMENT REMAINING IN PLACE...WILL HAVE TO WATCH ANY LINEAR STORM
FEATURES THAT DEVELOP FOR THE POSSIBILITY OF DAMAGING WIND GUSTS.
THAT SAID...BEST CHC OF ANY SEVERE STORMS WILL BE EAST AND SOUTH OF
OUR CWFA. THERE WILL BE QUITE A BIT OF ADDITIONAL RAINFALL ACROSS
THE AREA THIS MORNING...SO WILL HAVE TO KEEP AN EYE ON STREAM
LEVELS. ISOLATED FLOODING IS POSSIBLE...AND COULD BE LIMITED TO
MAINLY MORE URBANIZED LOCATIONS. WINDS WILL INCREASE AND BECOME
QUITE GUSTY BEHIND THE COLD FRONT THIS AFTERNOON. WIND GUSTS SHUD
REACH ADVISORY CRITERION ACROSS THE MTNS OF THE CAROLINAS AND NE GA.
WILL ISSUE A WIND ADVISORY FOR THESE LOCATIONS FROM 2 PM THRU
MIDNIGHT.
PRECIP TAPERS OFF QUICKLY THIS EVENING...BUT LINGERING MOISTURE IN
THE NW FLOW AND CAA COULD LEAD TO RAIN SHOWERS CHANGING TO SNOW
SHOWERS BEFORE ENDING BY MIDNIGHT. ANY SNOW WOULD BE LIGHT WITH NO
ACCUMS. ELSEHWERE...DIMINISHING WINDS AND CLEARING SKIES EXPECTED.
WITH THE VERY COLD AIR MASS MOVING IN...AN ADVECTIVE FREEZE IS
EXPECTED ACROSS MOST OF THE CWFA. WILL UPGRADE THE WATCH TO A
WARNING FOR ALL BUT THE NRN MTNS WHICH HAVE NOT REACHED THE
CLIMATOLOGICAL GROWING SEASON YET. LOWS WILL BE 15 TO NEARLY 20
DEGREES BELOW NORMAL...AND WILL THREATEN RECORDS AT AVL AND CLT. THE
RECORD AT GSP IS QUITE COLD AND SHOULD BE SAFE.
&&
.SHORT TERM /WEDNESDAY THROUGH THURSDAY/...
AS OF 310 AM TUESDAY...ON WEDNESDAY...THE CENTER OF SFC HIGH
PRESSURE IS EXPECTED TO BE CENTERED OVER THE MID APPALACHIANS AROUND
SUNRISE. THE HIGH CENTER WILL REACH NEW ENGLAND BY 0Z THURSDAY...BUT
WILL CONTINUE TO RIDGE ACROSS THE SOUTHEAST. STRONG INSOLATION
SHOULD RESULT IN GRADUAL WARMING...BUT LLVL THICKNESSES AND
TEMPERATURES WILL REMAIN UNSEASONABLE COOL. A BLEND OF PREFERRED MOS
SUPPORTS HIGH TEMPERATURES RANGING FROM THE MID 50S ACROSS THE MTN
VALLEYS TO NEAR 60 ACROSS THE UPPER SAVANNAH RIVER VALLEY. FORECAST
SOUNDINGS INDICATE THAT AFTERNOON MIXING MAY REACH AROUND 3
KFT...WITH PW VALUES AROUND 0.20 INCHES. AFTERNOON DEWPOINTS MAY MIX
TO THE TEENS...RESULTING IN RH VALUES AROUND 20 PERCENT.
WEDNESDAY NIGHT...A DRY AND COOL AIR MASS WILL REMAIN RIDGED ACROSS
THE CWFA. LIGHT NE WINDS AND CLEAR SKY CONDITIONS SHOULD RESULT IN
FAVORABLE RADIATIONAL COOLING CONDITIONS. LOW TEMPERATURES ARE
EXPECTED TO RANGE FROM U20S TO NEAR 30 ACROSS THE NC
MTNS...FOOTHILLS...AND PIEDMONT. LOW TEMPERATURES ACROSS THE UPSTATE
AND NE GA MAY RANGE IN THE LOW TO MID 30S. ON THURSDAY...SHORT RANGE
MODELS INDICATE THAT H85 TEMPERATURES WILL WARM 2-4 DEGREES FROM
WED. HIGH TEMPERATURES ON THURSDAY SHOULD WARM AROUND 3 DEGREES
WARMER THAN VALUES OBSERVED ON WED.
&&
.LONG TERM /THURSDAY NIGHT THROUGH MONDAY/...
AS OF 340 AM TUESDAY...MEDIUM RANGE GUIDANCE INDICATES THAT A H5
TROF AXIS WILL SLOWLY RIPPLE ACROSS THE SOUTHEAST LATE THIS WEEK.
THE PASSAGE OF THE TROUGH MAY RESULT IN A PERIOD OF UNSETTLED
WEATHER FOR FRIDAY AND SATURDAY. HOWEVER...BOTH THE GFS AND ECMWF
INDICATE THAT A LOW MAY DEVELOP OFF THE SOUTHEAST COAST LATE FRIDAY
AND SATURDAY...WITH A SECOND AREA OF LOW PRESSURE ACROSS THE UPPER
OHIO RIVER VALLEY. COVERAGE OF QPF ACROSS THE CWFA REMAINS VERY
LIMITED BETWEEN THE TWO SYSTEMS. I WILL MAINTAIN SCHC TO CHC POPS
FOR SHRA BETWEEN FRI TO SAT. SUN...MID LEVEL SHALLOW RIDGING WILL
BUILD ACROSS THE REGION...WITH WEAK WAA. TEMPERATURES ARE FORECAST
TO RETURN TO AROUND NORMAL VALUES. ON MON...A SOUTHERN STREAM LOW
MAY DEVELOP AHEAD OF MID LEVEL SHORTWAVE ACROSS THE DEEP SOUTH.
MOISTURE AND LIFT ASSOCIATED WITH THE LOW MAY SUPPORT A FEW SHRA MON
AFTERNOON.
&&
.AVIATION /13Z TUESDAY THROUGH SATURDAY/...
AT KCLT...LOW CLOUDS HAVE DISSIPATED AS HEAVY RAIN HAS MOVED EAST OF
THE AREA. EXPECT A RETURN TO MVFR LATER THIS MORNING AHEAD OF A COLD
FRONT MOVING INTO THE AREA...ALONG WITH CONTINUED SHRA. THERE IS A
CHANCE THAT IFR CIGS WILL DEVELOP OVER THE NEXT COUPLE
HOURS...THOUGH CONFIDENCE ISN/T HIGH ENOUGH TO INCLUDE THAT AT THIS
TIME. THE CHC FOR TSRA LOOKS TO BE AROUND 18Z NEAR THE TIME OF
FROPA. HAVE MADE THE WIND SHIFT TO NW AT THAT TIME AS WELL. GUSTY NW
WINDS WITH CLEARING SKIES THRU THE AFTERNOON. GUSTS CONTINUE INTO
THRU MUCH OF THE NITE WITH WINDS TURNING NLY AND GUSTS DIMINISHING
TOWARD DAYBREAK.
ELSEWHERE...SIMILAR CONDITIONS TO KCLT...EXCEPT EARLIER
ONSET...FROPA AND IMPROVEMENT. TSRA CHC MUCH LESS AT THESE
LOCATIONS...SO HAVE LEFT OUT FOR NOW. VERY GUSTY WINDS EXPECTED ALL
LOCATIONS AS WELL. KAND WILL SEE MORE WLY WIND THAN NW. KAVL MAY SEE
SOME LINGERING LOW VFR CLOUDS DURING THE AFTERNOON AND EVENING.
OUTLOOK...HIGH PRESSURE WILL PRODUCE VFR WEATHER WEDNESDAY AND
THURSDAY. CEILING AND VISIBILITY RESTRICTIONS WILL RETURN FRIDAY AND
SATURDAY AS A COLD FRONT APPROACHES FROM THE WEST AND A LOW PRESSURE
SYSTEM DEVELOPS ALONG THE COAST.
CONFIDENCE TABLE...
13-19Z 19-01Z 01-07Z 07-13Z
KCLT HIGH 87% HIGH 94% HIGH 100% HIGH 100%
KGSP HIGH 92% HIGH 100% HIGH 100% HIGH 100%
KAVL HIGH 85% HIGH 98% HIGH 100% HIGH 100%
KHKY HIGH 91% HIGH 100% HIGH 100% HIGH 100%
KGMU HIGH 92% HIGH 100% HIGH 100% HIGH 100%
KAND HIGH 90% HIGH 100% 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
&&
.CLIMATE...
RECORD LOWS FOR WEDNESDAY APRIL 16...
AVL...26 IN 1943
CLT...29 IN 2008
GSP...24 IN 1907
&&
.GSP WATCHES/WARNINGS/ADVISORIES...
GA...FREEZE WARNING FROM 11 PM THIS EVENING TO 10 AM EDT WEDNESDAY
FOR GAZ010-017-018-026-028-029.
WIND ADVISORY UNTIL MIDNIGHT EDT TONIGHT FOR GAZ010-017.
NC...FREEZE WARNING FROM 11 PM THIS EVENING TO 10 AM EDT WEDNESDAY
FOR NCZ035>037-048-051>053-056>059-062>065-068>072-082-
501>510.
WIND ADVISORY UNTIL MIDNIGHT EDT TONIGHT FOR NCZ033-048>053-
058-059-062>065-501-503-505-507-509.
SC...FREEZE WARNING FROM 11 PM THIS EVENING TO 10 AM EDT WEDNESDAY
FOR SCZ001>014-019.
WIND ADVISORY UNTIL MIDNIGHT EDT TONIGHT FOR SCZ001>003.
&&
$$
SYNOPSIS...NED
NEAR TERM...MCAVOY/RWH
SHORT TERM...NED
LONG TERM...NED
AVIATION...MCAVOY/RWH
CLIMATE...
AREA FORECAST DISCUSSION
NWS BLACKSBURG VA
203 AM EDT TUE APR 15 2014
.SYNOPSIS...
A COLD FRONT WILL APPROACH THE AREA FROM THE WEST LATE TONIGHT AND
PASS ACROSS THE REGION DURING TUESDAY RESULTING IN WIDESPREAD
SHOWERS. MUCH COLDER AIR WILL RUSH IN BEHIND THE FRONT TUESDAY
AFTERNOON AS UNSEASONABLY COLD HIGH PRESSURE BEGINS TO BUILD IN
ON STRONG NORTHWEST WINDS INTO TUESDAY NIGHT. THE HIGH WILL BUILD
OVER THE MID ATLANTIC REGION WEDNESDAY THROUGH FRIDAY.
&&
.NEAR TERM /THROUGH TODAY/...
AS OF 830 PM EDT MONDAY...
SHOWERS HAVE BEEN SLOW TO EVOLVE THIS EVENING WITH MOSTLY
LIGHT RAINFALL SEEN ACROSS THE SRN BLUE RIDGE ATTM DESPITE
INCREASING MOISTURE OFF EVENING SOUNDINGS. MODELS REMAIN OVERDONE
WITH DEGREE OF LIFT UNDER PASSING SHORTWAVES WELL AHEAD OF THE
MAIN UPPER TROF THIS EVENING AS THE FLOW REMAINS MORE SW AND
FORCING WEAK. LATEST HRRR SEEMS TO HAVE A HANDLE ON LIGHTER SHRA
FOR A WHILE LONGER BEFORE THE FLOW DEEPENS/BACKS AND BETTER
ISENTROPIC LIFT KICKS IN WITH AN INCREASING SOUTHERLY JET ESPCLY
AFTER MIDNIGHT. HAVE ALREADY UPDATED TO LOWER POPS THIS
EVENING...THEN QUICKLY REBOUND TO CATEGORICAL MOST SECTIONS
OVERNIGHT AS BANDS OF SHRA BEGIN TO LIFT NORTH AHEAD OF THE WAVE
AS WEAK INSTABILITY SHIFTS NORTH ACROSS SOUTHERN/EASTERN SECTIONS
LATE. GIVEN THIS ALONG WITH STRONGER WIND FIELDS INCLUDED A LOW
TOPPED TSRA MENTION ESPCLY FAR WEST JUST AHEAD OF THE FRONT AROUND
DAWN AND OUT EAST FOR LOW TOPPED BANDS LATE AS WELL. BUMPED UP
LOWS A LITTLE OUT WEST AS EXPECT THE FRONT TO BE JUST SLOW ENOUGH
TO KEEP MOST TEMP FALLS FROM OCCURRING UNTIL THE MORNING. OTRW A
MILD NIGHT WITH LOWS 50S TO LOWER 60S.
WINDS AND LOW TOPPED SHRA THE MAIN CONCERNS DURING TUESDAY WITH
STRONG ENOUGH GUSTS TO SUPPORT AT LEAST AN ADVISORY BLUE RIDGE
SECTIONS WITH POSSIBLE BANDED SHRA OUT EAST DESPITE LIMITED
INSTABILITY. AFTER COORDINATION WITH OTHER OFFICES HAVE DECIDED TO
GIVE THE MIDSHIFT ANOTHER LOOK RATHER THAN HOISTING A WIND
ADVISORY TONIGHT AS MAY BE CLOSE TO WARNING CRITERIA OVER THE SW
FOR A PERIOD TUESDAY AFTERNOON. OTRW MADE SOME ADJUSTS TO TIMING
OF THE HEAVIER SHRA AND POSSIBLE ISOLATED TSRA TUESDAY.
PREVIOUS DISCUSSION AS OF 320 PM EDT MONDAY...
SHOWERS STARTING TO ENTER THE WRN CWA THIS AFTERNOON. 12Z MODELS AND
LATEST LOCAL HIGH-RES FAVOR SLOWER TIMING TO THE EAST THRU
DUSK...BUT BY MIDNIGHT MOST AREAS WILL SEE LIKELY TO CATEGORICAL
POPS AS SERIES OF UPPER VORTS MOVING AHEAD OF THE FRONT SHIFT FROM
THE GULF COAST STATES INTO VA. APPEARS THUNDER THREAT WILL STAY
ISOLATED AT BEST GIVEN INSTABILITY IS WEAK. GOOD JET DYNAMICS WILL
LEAD TO POCKETS OF HEAVY RAIN OVERNIGHT INTO TUESDAY...AS FRONT
APPROACHES. MODELS IN AGREEMENT EASING THE FRONT INTO THE MOUNTAINS
BY 12Z-15Z TUESDAY AND SHIFTING TO THE EAST OF THE FORECAST AREA BY
LATE TUE AFTERNOON. DESPITE FRONT MOVING THROUGH APPEARS ENOUGH LIFT
AROUND THE BACKSIDE WITH SOUTHERLY JET TO KEEP THREAT OF RAIN WELL
INTO TUESDAY AFTERNOON. RUSH OF COLDER AIR WORKS IN ABOUT 2-4 HOURS
BEHIND THE FRONT CHANGING ANY LINGERING PRECIP TO SNOW SHOWERS IN
THE HIGHER ELEVATIONS. GIVEN WARMER GROUND THE SNOW AMOUNTS THROUGH
TOMORROW WILL BE LESS THAN AN INCH OVER THE RIDGETOPS ABOVE 3000 FT.
WILL HAVE TO WATCH FOR ISOLATED FLOODING GIVEN WAVES OF LOW PRESSURE
ALONG THE FRONT AND POTENTIAL FOR SOME TRAINING...ALTHOUGH SPEED OF
FRONT MAY HINDER IT SOME. STILL QPF LOOKING ON THE ORDER OF 1 TO 1.5
INCHES...THOUGH LOCALLY HIGHER SEEMS LIKELY IN HEAVIER DOWNPOURS.
WILL HOLD OFF ON ANY FLOOD WATCHES. EVEN THE RIVER ENSEMBLE
FORECASTS ARE NOT TAKING ANY RIVER STAGES ABOVE FLOOD STAGE. WILL
HAVE TO WATCH SOUTH BOSTON ON THE DAN THOUGH...GIVEN AMOUNTS SEEM
SIMILAR TO LAST WEEK.
THE OTHER ISSUE SHOULD BE WINDS BEHIND THE FRONT AS 6 HR PRESSURE
RISES ON THE ORDER OF 6 TO 12 MB ARE EXPECTED. MADE SOME ADJUSTMENTS
UP IN WIND GUSTS TO 40 KNOTS ACROSS THE SRN BLUE RIDGE AND ADJACENT
AREAS. WILL ALLOW FOR ONE MORE RUN OF THE MODELS AS CLOUD COVER WILL
TEMPER SOME OF THE GUSTS ABOVE INVERSION. HWO WILL MENTION WIND
ADVISORY POTENTIAL.
AS FOR TEMPS WILL BE SEEING SLOW FALLING AT BEST OVERNIGHT WITH
CONTINUED SOUTH FLOW...WITH SHOWERS HELPING TO COOL IT SOME.
TOMORROW WILL BE MILD IN THE FAR EAST BUT TEMPS WILL BE FALLING TO
THE FREEZING MARK INTO THE UPPER 30S ACROSS THE MOUNTAINS BY DUSK.
&&
.SHORT TERM /TONIGHT THROUGH THURSDAY NIGHT/...
AS OF 355 PM EDT MONDAY...
H85 TEMPS PLUNGE BEHIND STRONG COLD FRONT TUESDAY NIGHT...NEARING
-12C PER THE GFS. MOISTURE DRIES OUT RATHER QUICKLY ALOFT...BUT
SHOULD BE ENOUGH TO GENERATE AN HOUR OR TWO OF UPSLOPE SNOW
SHOWERS ACROSS WESTERN GREENBRIER WHERE A QUICK HALF INCH OR LESS
MAY FALL ABOVE 2500 FEET. SNOW SHOWERS/FLURRIES MAY FALL FOR A
BRIEF TIME DOWN TO BLUEFIELD...BUT NO ACCUMULATION IS EXPECTED.
SKIES SHOULD CLEAR RAPIDLY....WITH STRONG DOWNSLOPE...AND H85 JET
NEAR 50KTS SHOULD PRODUCE WIND ADVISORY CRITERIA ACROSS NW
NC/EXTREME SW VA AT THE VERY LEAST. POSSIBLY A SMALL WINDOW
TUESDAY EVENING WITH HIGH WIND CRITERIA GUSTS NW NC. 1030MB HIGH
PRESSURE NOSES ACROSS THE MOUNTAINS QUICKLY...AND MOS GUIDANCE IS
SOLIDLY AT OR BELOW 32F FOR LOWS WED MORNING EVEN ACROSS THE
PIEDMONT/SOUTHSIDE. BECAUSE OF THIS ISSUED A FREEZE WATCH EAST OF
THE BLUE RIDGE. WINDS SHOULD HOLD THROUGH MUCH OF THE NIGHT...AND
SOMETIMES LOWS COME IN A FEW DEGREES WARMER IN THIS SETUP. THUS
THE CHANCE OF A WIDESPREAD FREEZE MAY BE MARGINAL ACROSS THE
SOUTHEASTERN CWA...SOUTHSIDE/NC PIEDMONT. MUCH BETTER CHANCE NORTH
OF THIS REGION. SURFACE HIGH PRESSURE WEDGING DOWN THE
APPALACHIANS IS PRETTY MUCH LOCKED IN THROUGH THURSDAY
NIGHT...WITH DRY SUNNY DAYS AND COLD NIGHTS EXPECTED. WITH LESS
WIND WEDNESDAY NIGHT AND DEWPOINTS INTO THE TEENS WED PM...CONDS
MAY BE EVEN MORE FAVORABLE FOR MORE WIDESPREAD FREEZE...WITH
ANOTHER WATCH NECESSARY WED NIGHT/THURS MORNING.
&&
.LONG TERM /FRIDAY THROUGH MONDAY/...
AS OF 355 PM EDT MONDAY...
WEAK TROUGH THROUGH THE MIDWEST EVENTUALLY PUSHES EAST...AND
WEDGING HIGH PRESSURE EVENTUALLY DEPARTS THIS WEEKEND. WITH A
RATHER DRY ANTECEDENT AIRMASS...QUESTIONABLE IF THIS MIDWEST
TROUGH PRODUCES ANY PRECIP ONCE IT ARRIVES ACROSS THE OHIO VALLEY
AND MIDDLE ATLANTIC THIS WEEKEND. OP GFS IS FAR MORE WET THAN THE
ECMWF. THUS...POPS WERE KEPT RATHER LOW. A ZONAL UPPER FLOW TAKES
SHAPE BY LATE WEEKEND INTO EARLY NEXT WEEK...WITH UNEVENTFUL AND
DRY WEATHER CONTINUING ACROSS THE REGION.
&&
.AVIATION /06Z TUESDAY THROUGH SATURDAY/...
AS OF 150 AM EDT TUESDAY...
MVFR TO IFR CIGS/VSBYS IN AREAS OF RAIN SHOWERS AND FOG EXPECTED
THROUGH AROUND 18Z...AT WHICH POINT A STRONG COLD FRONT WILL MOVE
THROUGH...IMPROVING CIGS TO VFR AFT 18Z PIEDMONT...BUT WITH
CONTINUED MVFR CIGS IN UPSLOPE FLOW AND -SHRA OR EVEN POSSIBLY
-SHSN EASTERN WV TAF SITES. BCB WILL SEE PERIODS OF MVFR CIGS
CONTINUING THROUGH EVENING. MVFR VSBYS MAY CONTINUE AT BLF FOR A
WHILE IN THE AFTERNOON/EARLY EVENING...BUT SHOULD IMPROVE TO VFR
AT ALL OTHER SITES BY 20Z. WINDS WILL BE ONE OF THE GREATEST
CONCERNS THIS TAF VALID CYCLE...MAINLY BEHIND THE FRONT. AHEAD OF
THE FRONT...A GENERAL INCREASE OF SSE-SSW WINDS OF 10-20KTS CAN BE
EXPECTED...BUT BEHIND THE FRONT...EXPECT WNW-NW 15-20KTS WITH
GUSTS 30-40KTS. IT APPEARS THAT THIS WILL ONLY BE FOR A FEW
HOURS...THEN DIMINISHING FAIRLY RAPIDLY AFT 02Z.
MEDIUM CONFIDENCE IN CIGS/VSBYS THROUGH THE TAF VALID PERIOD.
MEDIUM TO HIGH CONFIDENCE IN WIND DIR/SPD THROUGH THE TAF VALID
PERIOD.
LOW CONFIDENCE IN POTENTIAL FOR TSRA ROA/LYH/DAN AND LOW
CONFIDENCE FOR -SHSN AT BLF/LWB THROUGH TAF VALIDP PERIOD.
EXTENDED AVIATION DISCUSSION...
MUCH DRIER AIR WORKS IN BEHIND THE FRONT WEDNESDAY WITH STRONG
HIGH PRESSURE WEDGED IN FROM THE NE. THIS SHOULD ALLOW A RETURN TO
WIDESPREAD VFR WITH THIS SCENARIO CONTINUING THURSDAY WITH HIGH
PRESSURE RIDGING IN FROM OFF NEW ENGLAND AND THE NEXT COLD FRONT
TO THE NW. THIS FRONT APPROACHES FROM THE WEST FRIDAY BUT APPEARS
SLOW AND WEAK ENOUGH TO MAINTAIN VFR DURING THE DAY FOR NOW. THIS
SYSTEM MAY BRING MVFR CIGS TO THE MOUNTAINS SATURDAY ALONG WITH A
FEW SHOWERS OTRW VFR ELSW TO START THE WEEKEND.
&&
.RNK WATCHES/WARNINGS/ADVISORIES...
VA...FREEZE WATCH FROM LATE TONIGHT THROUGH WEDNESDAY MORNING FOR
VAZ022>024-032>035-043>047-058-059.
NC...FREEZE WATCH FROM LATE TONIGHT THROUGH WEDNESDAY MORNING FOR
NCZ003>006-019-020.
WV...NONE.
&&
$$
SYNOPSIS...AMS/JH/WP
NEAR TERM...JH/WP
SHORT TERM...KM
LONG TERM...KM
AVIATION...JH/RAB
AREA FORECAST DISCUSSION
NWS EUREKA CA
905 PM PDT WED APR 16 2014
.SYNOPSIS...A WEAK FRONTAL BOUNDARY WILL BRING LIGHT RAIN TO AREAS
NORTH OF CAPE MENDOCINO ON THURSDAY. THEN...BUILDING HIGH PRESSURE
WILL RESULT IN A MOSTLY DRY WEEKEND BEFORE A STRONGER SYSTEM
IMPACTS NORTHWEST CALIFORNIA. THIS SYSTEM IS CAPABLE OF BRINGING
RAIN AND MOUNTAIN SNOW TO THE REGION BY EARLY NEXT WEEK.
&&
.UPDATE...11-4U SAT IMAGERY SHOWED STRATUS DEVELOPING RAPIDLY OVER
THE WATERS THIS EVENING AND EXPANDING TOWARDS THE COAST. MESO
MODELS SHOW BL MOISTURE INCREASING ALONG THE COAST AND COASTAL
RIVER VALLEYS TONIGHT. THE EXCEPTION IS ALONG THE DEL NORTE COAST
WHERE THE RAP SHOWS OFFSHORE WINDS DEVELOPING FOR AN HOUR OR TWO
AFTER 09Z...HOWEVER...CONFIDENCE IS LOW ON HOW MUCH CLEARING MAY
OCCUR. SAT IMAGERY ALSO SHOWS LESS HIGH CLOUDS OVER CWA THIS
EVENING. IF THIS TREND CONTINUES OVERNIGHT...BETTER RADIATIONAL
COOLING WILL MAKE THREAT OF FROST POSSIBLE. ALTHOUGH TEMPS ARE
RUNNING A DEGREE OR TWO HIGHER THAN LAST NIGHT...TRENDS WILL NEED
TO BE MONITORED OVERNIGHT. ISSUED QUICK UPDATE TO ADD FG AND
INCREASE SKY COVER OVER THE WATERS AND ALONG THE COAST WHILE
REDUCING SKY COVER INLAND THROUGH THU MORNING. UPDATED AVIATION
AND MARINE DISCUSSIONS FOLLOW.
&&
.AVIATION...STRATUS DEVELOPED RAPIDLY OVER THE WATERS THIS EVENING
AND WILL PLAGUE THE COAST N OF CAPE MENDO THROUGH THE NIGHT. MESO
MODELS SHOW WINDS ALONG THE COAST VARYING BETWEEN ONSHORE AND
OFFSHORE MAKING FOR A TRICKY FCST. EXPECT IFR CONDITIONS TO
PREVAIL ALONG THE COAST WITH PERIODS OF VFR AS WINDS SHIFT
OFFSHORE. INLAND...EXPECT VFR CONDITIONS TO PREVAIL WITH LIGHT
TERRAIN DRIVEN WINDS. INCREASING MID AND HIGH CLOUDS THURSDAY AS A
FRONT APPROACHES NORTHERN CALIFORNIA. /KENNEDY
&&
.MARINE...NEAR GALE TO GALES CONTINUE ACROSS FAR SRN PORTIONS OF
THE SRN WATERS. GIVEN THE LIMITED AREAL COVERAGE...ELECTED TO
ALLOW GALE WARNING TO EXPIRE AND HOISTED A SCA THROUGH THU
MORNING AS WINDS AND SEAS WILL CONTINUE TO DIMINISH OVERNIGHT.
CONDITIONS WILL DETERIORATE AGAIN THIS WEEKEND AS A STRONG LOW
PRESSURE SYSTEM MOVES INTO THE EASTERN GULF OF ALASKA AND GENERATES
ELEVATED WESTERLY SWELLS THAT WILL PROPAGATE THROUGH THE OFFSHORE
WATERS. /KENNEDY
&&
.PREV DISCUSSION......ISSUED AT 430 PM PDT...
A BUILDING RIDGE OF HIGH PRESSURE POSITIONED OVER THE WESTERN
UNITED STATES HAS RESULTED IN A MOSTLY CLEAR DAY ACROSS NORTHERN
CALIFORNIA. CLEAR SKIES WILL BE SHORT LIVED AS CLOUD COVER ALOFT
INCREASES OVERNIGHT WITH THE APPROACH OF A SHORTWAVE TROUGH. THIS
SYSTEM WILL BRING THE NEXT OPPORTUNITY FOR LIGHT RAIN ON THURSDAY.
MOST RAIN WILL BE RESTRICTED NORTH OF CAPE MENDOCINO WITH AMOUNTS
AROUND 0.10" OR LESS AND PERHAPS UP TO 0.25" IN THE MOUNTAINS OF
DEL NORTE COUNTY. FRIDAY AND SATURDAY WILL BE MOSTLY DRY BEFORE
ANOTHER SYSTEM BRINGS A BRIEF SHOT OF RAIN SATURDAY NIGHT INTO
SUNDAY. AGAIN, THE BEST CHANCES WILL BE RESTRICTED TO AREAS NORTH
OF CAPE MENDOCINO WITH PRECIPITATION AMOUNTS TO REMAIN VERY LIGHT.
A MORE PROMINENT SYSTEM IS EXPECTED TO IMPACT THE PACIFIC NORTHWEST
EARLY NEXT WEEK AS A LOW OFF THE COAST OF BRITISH COLUMBIA DIGS
SOUTHWARD. LONG RANGE MODELS HAVE BEEN DOING A POOR JOB HANDLING
SHORTWAVES IN THE EXTENDED, HOWEVER, CONFIDENCE HAS INCREASED SINCE
FORECAST CONFIDENCE TOOLS HAVE SIGNALED A TREND TOWARDS A DEEPENING
LOW OVER THE PAST FEW DAYS. THERE IS STILL UNCERTAINTY IN ARRIVAL
TIME OF THIS SYSTEM BUT PAST MODEL RUNS SHOW THE ECMWF HAS BEEN
TRENDING TOWARDS THE MORE PROGRESSIVE GFS. AS A RESULT, STARTING ON
MONDAY POPS HAVE BEEN INCREASED FROM AN ALL MODEL BLEND WITH THE CAP
UP IN 50 THE PERCENT RANGE AND ABOVE CLIMO POPS FOR THE TAIL END OF
THE FORECAST.KML
&&
.EKA WATCHES/WARNINGS/ADVISORIES...
SMALL CRAFT ADVISORY UNTIL 3 AM PDT THU FOR PZZ455.
SMALL CRAFT ADVISORY UNTIL 9 AM PDT THU FOR PZZ475.
&&
$$
VISIT US AT HTTP://WWW.WEATHER.GOV/EUREKA
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AREA FORECAST DISCUSSION
NWS PUEBLO CO
1111 PM MDT WED APR 16 2014
.UPDATE...
ISSUED AT 849 PM MDT WED APR 16 2014
UPDATED LATEST TEMPS AND MADE MINOR CHANGES TO TEMPS OVERNIGHT.
ADJUSTED SOME SNOWFALL AMOUNTS FOR THE REST OF TONIGHT.
&&
.SHORT TERM...(THIS EVENING THROUGH THURSDAY)
ISSUED AT 254 PM MDT WED APR 16 2014
...HEAVY WET SNOW FOR THE SOUTHEASTERN MOUNTAINS TONIGHT...
RAPIDLY EVOLVING STORM SYSTEM NOW IS MOVING INTO WRN CO THIS
AFTERNOON. ALREADY AM SEEING SOME BANDED PRECIP...IN THE FORM OF
SHRA...DEVELOP OVER EL PASO COUNTY. DEWPOINTS STILL PRETTY LOW OVER
THE PLAINS...WHICH WILL HELP COOL THINGS OFF THIS EVE AS WET BULB
IS REACHED IN HEAVIER PRECIP. EXPECT PRECIP TO EXPAND AND INTENSIFY
THROUGH THE AFTERNOON...REACHING ITS PEAK FROM 00Z THROUGH 06Z
TONIGHT.
A COUPLE OF RECENT TRENDS ARE MAKING FOR A RATHER TRICKY FORECAST
FOR THE SHORT TERM. RECENT GUIDANCE IS CONSIDERABLY WARMER THAN IT
HAD BEEN A COUPLE DAYS AGO...WITH H7 TEMPS ONLY FALLING TO MINUS
5 OR 6 AS OPPOSED TO THE MINUS 10 OR LOWER FROM EARLIER MODEL RUNS.
THIS IS POINTING AT THE SNOW LEVELS GENERALLY STAYING AT OR
ABOVE 6000 FEET TONIGHT. BUT DEPENDING ON EVENTUAL STRENGTH AND
TIMING...WOULD NOT BE SURPRISED TO SEE SNOW FALLING AT THE LOWER
ELEVATIONS. JUST NOT EXPECTING MUCH IF ANY ACCUMULATION BELOW 6K
FEET...EXCEPT MAYBE ON GRASSY SURFACES. THE WINTER WX ADVISORY FOR
THE SRN I-25 CORRIDOR WILL BE A PARTICULAR CHALLENGE SINCE
ELEVATIONS FROM WALSENBURG TO TRINIDAD ARE GENERALLY IN THE 6000-
6500 FOOT RANGE. SO...EVEN A SLIGHT SHIFT IN THE LOW LEVEL
TEMPERATURES THIS EVE COULD MAKE THE DIFFERENCE BETWEEN WET PAVEMENT
AND A FEW INCHES OF SLUSH. HAVE GENERALLY PLAYED THE MIDDLE ROAD OF
MODEL CONSENSUS...WHICH HAS SNOW LEVELS AT OR ABOVE THAT ELEVATION
FOR THE EARLY EVE. BUT...HIGHER TRRN TO THE WEST AND CLOSER TO
SPANISH PEAKS COULD SEE SIGNIFICANT WET SNOW...MORE THAN SIX INCHES
FOR SOME AREAS.
OTHER ISSUE IS THE RECENT TREND TOWARDS THE HEAVIEST ACCUMS FALLING
OVER THE SRN ZONES...THE WETS AND SRN SANGRES GENERALLY SOUTH OF
HIGHWAY 50. THE HRRR AND LOCAL HI-RES WRF...FOR EXAMPLE...KEEP
MOST OF THE HEAVY PRECIP SOUTH OF THE PIKES PK REGION. THE NAM
AND RUC..LOWER RES...KEEP HEAVY PRECIP OVER THE PIKES PEAK REGION.
GIVEN THE POOR PERFORMANCE OF THE HIGHER RES SOLUTIONS SO FAR...AM
INCLINED TO KEEP WITH AT LEAST MODERATE ACCUMS FOR PIKES
PEAK...ALTHOUGH IT SEEMS REASONABLE THAT SRN AND ERN SIDES WILL GET
A BIT MORE THIS EVE. MODELS ARE HITTING THE SRN SANGRES AND HIGHER
WETS PRETTY HARD THROUGH 06-08Z TONIGHT. HAVE CONSIDERED UPGRADING
FOR THOSE ZONES...BUT SINCE THE LIQUID-SNOW RATIOS WILL BE HIGHER
GIVEN THE WARMER LOW-LEVEL THERMAL PROFILE...EXPECT THE MORE
SIGNIFICANT ACCUMS TO BE PRETTY HIGH UP AND SPOTTY. SO...ADVISORIES
LOOK GOOD FOR NOW BUT WILL HAVE TO FOLLOW THE SHORT TERM TRENDS
PRETTY CAREFULLY.
WILL SEE THE SYSTEM CLEAR OUT GRADUALLY FROM N TO S AFTER MIDNIGHT.
COULD EVEN SEE SOME CLEARING BY SUNRISE ON THURSDAY. BALANCE OF
THURSDAY LOOKS PRETTY NICE...WITH TEMPS REBOUNDING TO THE UPPER 50S
OVER THE PLAINS BY AFTERNOON...AND INCREASING AMOUNTS OF SUN. ROSE
.LONG TERM...(THURSDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 254 PM MDT WED APR 16 2014
NEXT SYSTEM WILL BE MOVING INTO THE REGION OVER THE WEEKEND BRINGING
A RETURN OF ACTIVE WEATHER IN THE EXTENDED. CLOSED LOW MOVES IN
FROM THE PACIFIC...ACROSS SOUTHERN CA AND INTO THE DESERT SOUTHWEST
THROUGH FRIDAY NIGHT. MOISTURE INCREASES...PARTICULARLY ACROSS
WESTERN AREAS ON FRIDAY...SO SHOULD SEE ISOLATED TO SCATTERED RAIN
AND HIGHER ELEVATION SNOW SHOWERS OVER THE MOUNTAINS WITH SOME
ISOLATED EMBEDDED THUNDERSTORMS POSSIBLE DURING THE AFTERNOON. ANY
SNOWFALL ACCUMULATIONS LOOKS LIGHT THROUGH THIS PERIOD...AND
CONFINED TO THE HIGHER ELEVATIONS.
THIS SYSTEM WILL GRADUALLY FILL AS IT MOVES INTO THE FOUR CORNERS
REGION ON SATURDAY THEN ACROSS CO THROUGH SUNDAY MORNING AS AN OPEN
TROF. PRECIPITATION WILL INCREASE ACROSS THE SOUTHWEST MOUNTAINS
FRIDAY NIGHT...THEN SPREAD ACROSS ALL OF THE MOUNTAINS AND ADJACENT
PLAINS ON SATURDAY. WITH COOLING ALOFT...LAPSE RATES STEEPEN...AND
A COLD FRONT...THOUGH IT IS NOT ALL THAT COOL BEHIND IT...WILL MOVE
THROUGH THE SOUTHEAST PLAINS DURING THE AFTERNOON. NAM12 IS THE
FARTHEST SOUTH WITH THE FRONT SAT AFTERNOON SHOWING EASTERLY WINDS
ACROSS THE PLAINS AND DEW POINTS INCREASING INTO THE 40S TO AROUND
50 NEAR THE EASTERN BORDER BY 00Z. GFS IS A TAD SLOWER...WITH
NORTHERLY WINDS DROPPING THROUGH THE I-25 CORRIDOR DURING THE
AFTERNOON...AND DEW POINTS IN THE 30S THROUGH THE AFTERNOON. ECMWF
IS FAIRLY SIMILAR TO THE GFS...THOUGH A JUST A TAD MOISTER. EITHER
WAY...SNOW LEVELS WILL BE ON THE HIGH SIDE AGAIN...PROBABLY AROUND
9.5-10KFT...SO BELOW THIS ELEVATION WILL HAVE TO MONITOR THE BURN
SCARS CLOSELY FOR RAINFALL...ESPECIALLY THE WALDO. FOR NOW
THOUGH...THINK THAT GFS PROBABLY HAS THE BEST HANDLE...AND ANY
LOCALLY HEAVIER PRECIPITATION AMOUNTS WILL BE SPOTTY AS MODEL CAPE
VALUES ARE NOT ALL THAT HIGH. ISOLATED THUNDERSTORMS WILL ALSO
SPREAD ACROSS THE SOUTHEAST PLAINS SATURDAY AFTERNOON AND
EVENING...THOUGH RAINFALL AMOUNTS LOOK FAIRLY LIGHT AT THIS POINT
AS HIGHER CAPE REMAINS WELL TO THE EAST.
THIS SYSTEM SLOWLY EXITS EASTERN CO ON SUNDAY...SO AFTER
PRECIPITATION WINDS DOWN OVERNIGHT...ENOUGH INSTABILITY AND RESIDUAL
MOISTURE WILL BE PRESENT FOR ANOTHER ROUND OF ISOLATED THUNDERSTORMS
SUNDAY AFTERNOON. THESE LOOK A LITTLE SPOTTIER IN COVERAGE.
DRY WEATHER RETURNS FOR EARLY NEXT WEEK...THEN THE FORECAST WILL
REVOLVE AROUND TRACK OF THE NEXT UPPER LOW WHICH DROPS INTO THE
GREAT BASIN...THEN EVENTUALLY LIFTS OUT TO THE NORTH OF THE FORECAST
AREA WED. THIS WILL PUT MOST OF SOUTH CENTRAL AND SOUTHEAST COLORADO
UNDER STRONG SOUTHWEST FLOW ALOFT WITH THE POTENTIAL FOR CRITICAL
FIRE WEATHER CONDITIONS DEVELOPING ESPECIALLY BY WEDNESDAY.
DEPENDING ON THE CONDITIONS OF FUELS...MAY NEED SOME FIRE WEATHER
HIGHLIGHTS FOR THIS DAY. OTHERWISE...DRY LINE WILL BE LURKING NEAR
THE CO/KS BORDER DURING THE EARLY TO MIDDLE PART OF NEXT WEEK.
TRENDS IN THE LATEST OPERATIONAL GFS AND ECMWF...SEEM TO SUGGEST
A MORE NORTHERN TRACK AND LESS OF A PERSISTENT MERIDIONAL FLOW
EARLY NEXT WEEK...SO THESE LATEST RUNS KEEP THE DRYLINE JUST TO
OUR EAST. HOWEVER...THERE ARE STILL SOME RATHER LARGE DIFFERENCES
IN THE EXTENDED MODELS FOR WED AS GFS SHOWS MORE ENERGY DROPPING
SOUTHWARD INTO THE BASE OF THE TROF ACROSS THE GREAT BASIN WHICH
EC DOES NOT HAVE...SO JURY IS STILL OUT. EITHER WAY...SHOULD BE AN
ACTIVE PERIOD THROUGH NEXT WEEK. -KT
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z THURSDAY NIGHT)
ISSUED AT 1107 PM MDT WED APR 16 2014
KALS...SNOW WILL CONTINUE THROUGH 08-10Z TONIGHT WITH REDUCED VIS
AND CIGS TO MVFR TO IFR. AN ADDITIONAL INCH OF SNOW IS POSSIBLE ON
AREA RUNWAYS. EXPECT IMPROVING CONDITIONS BY THURSDAY MORNING WITH
VFR CONDITIONS THROUGH THURSDAY EVENING.
KCOS...A RAIN AND SNOW MIX WILL CONTINUE THROUGH 10-12Z TONIGHT
WITH REDUCED CIGS AND VIS TO MVFR. EXPECT IMPROVING CONDITIONS
AFTER 12Z WITH VFR CONDITIONS THROUGH THURSDAY EVENING.
KPUB...LIGHT RAIN WILL CONTINUE...AND PERHAPS MIX WITH SNOW
THROUGH AROUND 12Z WITH REDUCED CIGS TO NEAR MVFR. EXPECT RAIN AND
SNOW TO DISSIPATE BY THURSDAY MORNING WITH VFR CONDITIONS EXPECTED
THROUGH THURSDAY AFTERNOON. MOZLEY
&&
.PUB WATCHES/WARNINGS/ADVISORIES...
WINTER WEATHER ADVISORY UNTIL 4 AM MDT THURSDAY FOR COZ072>075-
079>082-087-088.
&&
$$
UPDATE...28
SHORT TERM...ROSE
LONG TERM...KT
AVIATION...MOZLEY
AREA FORECAST DISCUSSION
NWS MELBOURNE FL
440 AM EDT THU APR 17 2014
.DISCUSSION...
...WET THROUGH SATURDAY WITH POTENTIAL FOR LOCALLY HEAVY RAINFALL
ESPECIALLY ALONG THE COAST...
...HAZARDOUS BOATING CONDITIONS THROUGH THIS WEEKEND AND INTO EARLY
NEXT WEEK...
TODAY-TONIGHT...POST FRONTAL DRY AIRMASS REMAIN FAIRLY PERVASIVE
ACROSS THE REGION...ESPECIALLY ACROSS THE INTERIOR AND VOLUSIA
COUNTY WHERE DEWPOINTS ARE STILL IN THE MID-UPPER 50S.
MODELS HAVE SO FAR BEEN VERY GUNG HO IN LIFTING THE OLD FRONTAL
BOUNDARY/ENHANCED MOISTURE BACK NORTH...BUT IT APPEARS THAT THE
NORTHWARD TREND MAY BE STARTING AS ONE HEAVY RAINBAND SET UP EARLIER
THIS EVENING ACROSS BROWARD COUNTY THAT HAS SINCE DISSIPATED.
CURRENT ANALYSIS SHOWS A BAND OF ENHANCED LOW LEVEL MOISTURE FROM
BREVARD/OSCEOLA COUNTIES SOUTHWARDS COINCIDENT WITH AN AREA OF WIND
CONVERGENCE IN THE 1000-850MB LAYER. THIS IS WHERE RADAR IS ALSO NOW
PICKING UP ON A RECENT UPSWING IN SHOWER COVERAGE.
LOCAL WRF MODEL SHOWS A BAND OF ENHANCED PRECIP AROUND DAYBREAK OVER
THE TREASURE COAST...BUT HRRR MODEL KEEPS THIS ACTIVITY MORE OVER
SOUTH FLORIDA UNTIL LATER. ITS TOUGH TO SAY WHERE OR IF ANY LOCALLY
HEAVY BANDS MAY SET UP UNTIL THEY DO...BUT JUST AHEAD OF/ALONG WARM
FRONT WOULD BE THE BEST BET. DO EXPECT AN INCREASE IN SHOWER
FREQUENCY TOWARDS DAYBREAK ACROSS THE TREASURE COAST.
FRONTAL REMNANTS AND BEST ISENTROPIC LIFT WILL MOVE BACK TO THE
NORTH ACROSS CENTRAL FLORIDA THROUGH THE DAY...ACCELERATING INTO
NORTH FLORIDA TONIGHT AS UPPER LEVEL SHORTWAVE SWINGS EASTWARDS AND
SURFACE LOW DEVELOPS ACROSS THE GULF. HAVE TAPERED BACK RAIN CHANCES
TO 20 PERCENT NORTHERN INTERIOR TO 60 PERCENT OKEECHOBEE/TREASURE
COAST BASED ON CURRENT TRENDS/MODEL FORECAST. COULD SEE A FEW
PERIODS OF HEAVY RAIN ALONG THE COAST TODAY...BEFORE THE BEST RAIN
CHANCES WILL LIFT NORTH OF THE REGION LATER TONIGHT.
THOUGH IT WILL BE BREEZY AGAIN THIS AFTERNOON...IT DOESN`T APPEAR
THAT SPEEDS/GUSTS WILL BE QUITE AS HIGH AS YESTERDAY SO HAVE NOT
ISSUED A LAKE WIND ADVISORY. HOWEVER CONDITIONS WILL STILL REMAIN
CHOPPY ON AREA LAKES.
COASTAL HIGHS WILL BE HIGHLY DEPENDENT ON CLOUD COVER AND PRECIP
TIMING...BUT OVERALL EXPECTED ANYWHERE FROM LOW 70S ALONG VOLUSIA
COAST TO UPPER 70S/AROUND 80 IN BREVARD/TREASURE COAST. INTERIOR
TEMPS IN THE UPPER 70S AND LOW 80S. MILD OVERNIGHT AS FLOW BECOMES
MORE EAST-SOUTHEAST WITH LOWS IN THE UPPER 60S INTERIOR/AROUND 70S
COAST.
FRI-SUN...THE OVERALL TREND OF THE SHORT RANGE FORECAST IS DECIDEDLY
SLOWER AND WETTER INTO SUNDAY. STRONG SOUTHERN STREAM SHORT WAVE
TROUGH WILL MOVE EAST ALONG THE ERN GULF COAST BEFORE PINCHING OFF
INTO A CLOSED MID-UPPER LOW INVOF THE FL/AL/GA TRI-STATE REGION FRI
NIGHT. THE CLOSED LOW WILL THEN DRIFT SLOWLY EAST SOMEWHERE BTWN THE
FL/GA BORDER AND PENINSULAR NORTH FL ON SAT...EASING OFFSHORE SAT
NIGHT AND DRIFTING FARTHER OFFSHORE AND AWAY FROM THE FL EAST COAST
ON SUN.
AT THE SURFACE...AVBL MODEL GUIDANCE HAS CONVERGED TOWARD A MORE
AGREEABLE (SLOWER) SOLUTION...ALTHOUGH THE GFS CONTINUES TO BE THE
FASTEST. SFC FRONTAL WAVE SPINS UP INTO A LOW AND TRACKS ACROSS THE
NERN GOMEX FRI...WITH THE SFC AND MID/UPPER LEVEL LOWS BECOMING
VERTICALLY STACKED BY FRI NIGHT OVER NORTH FL. SFC WARM FRONT LIFTS
NORTHWARD THROUGH CENTRAL FL DURING THE MORNING...WHICH SHOULD TAKE
WIDESPREAD STRATIFORM RAINFALL NWD ACROSS NORTH FL/GA...WHILE ECFL
BREAKS OUT INTO THE WARM SECTOR OF THE GOMEX LOW. DEEP LAYER S-SW
FLOW WITH PWATS AROUND 1.75" WILL LEAD TO WIDESPREAD SHOWERS/STORMS
WITH THE POTENTIAL FOR A BAND OF STRONGER STORMS TO REACH CTRL FL
FROM THE GOMEX (N/W OF I-4) AROUND SUNSET (GIVE OR TAKE) AND
CONTINUE TO DROP SEWD THROUGH THE EVENING HOURS.
SFC LOW WILL BE VERY SLOW TO MOVE ACROSS THE STATE FRI NIGHT...AND
THEN LINGER OFFSHORE THE FL EAST COAST THROUGHOUT SAT. SUFFICIENT
WRAP AROUND MOISTURE WILL EXIST FOR SCT TO NMRS SHOWERS...AND EVEN
SOME STORMS GIVEN THE COLD H50 TEMPS UNDERNEATH THE H50 LOW OVHD.
EXPECT LINGERING SHOWERS SAT NIGHT/SUNDAY IN COOL/MOIST NRLY FLOW
ON BACK SIDE OF THE LOW...WHICH WILL BE GRUDGINGLY SLOW TO PUT SPACE
BETWEEN ITSELF AND FL. COVERAGE/INTENSITY SHOULD BE RATHER LOW.
MON-WED...WEAK HIGH PRESSURE FINALLY SETTLES IN TOWARD FL EARLY NEXT
WEEK...AND DRYING CONDS OUT. THERE ARE SOME SUGGESTIONS OF A WEAK
FRONTAL TROUGH AND ASCD MOISTURE BAND TAKING A GLANCING SHOT AT NORTH
FL TUE-NIGHT INTO WED...BUT WILL NOT GET TOO INVOLVED IN DISSECTING
DAY 6-7 POPS GIVEN THE MORE SIG WX IN DAYS 1-3.
&&
.AVIATION...MOIST AND CLOUDY THROUGH THE PERIOD...THOUGH OVERALL IT
APPEARS MOST LOCATIONS WILL REMAIN JUST INSIDE VFR WITH PREVAILING
CIGS FL035-050. COASTAL SITES WILL BE MORE LIKELY TO SEE MVFR CIGS
FL020-030. ISOLD SHRA MOVING ONSHORE INTO AREAS SOUTH OF KVRB
THROUGH 13Z...THEN BECOMING SCT-NMRS. COVERAGE WILL INCREASE FROM
SOUTH-NORTH AS OLD FRONTAL BOUNDARY LIFTS BACK TO THE NORTH THROUGH
THE DAY. A FEW HEAVIER SHRA MAY PRODUCE TEMPO IFR CONDITIONS MAINLY
ALONG COASTAL SITES. COULD SEE PREVAILING IFR CIGS LATER TONIGHT AS
WARM FRONT LIFTS NORTH OF REGION.
&&
.MARINE...TODAY-TONIGHT...GUSTY NORTHEAST TO EAST FLOW WILL CONTINUE
TO PRODUCE HAZARDOUS CONDITIONS FOR SMALL CRAFT. PRESSURE GRADIENT
WILL REMAIN STRONGEST OVER WATERS NORTH OF SEBASTIAN INLET...KEEPING
WINDS IN THE 20-25KT RANGE INTO THIS EVENING. WARM FRONT LIFTING
BACK TO THE NORTH WILL EASE GRADIENT FURTHER SOUTH...VEERING WINDS
MORE EAST IN THE 15-20KT RANGE BY LATE MORNING OFF THE TREASURE
COAST. WINDS WILL VEER EAST-SOUTHEAST AND DROP TO 15-20KTS OVER ALL
THE WATERS BY LATE TONIGHT AS THE WARM FRONT LIFTS NORTH OF THE
REGION.
WILL KEEP ADVISORY FOR WINDS/SEAS NORTH OF SEBASTIAN INLET THROUGH
LATE TONIGHT WITH SEAS 5-7FT NEARSHORE/6-9FT OFFSHORE. WILL HAVE
ADVISORY FOR SEAS SOUTH OF SEBASTIAN INLET WHERE WINDS WILL BE
LIGHTER...BUT SEAS WILL BE SIMILAR TO NORTHERN SECTIONS DUE TO
INITIAL NORTHEASTERLY TRAJECTORY.
FRI-MON...A SLIGHT DECREASE IN WINDS/SEAS IS EXPECTED AS THE WARM
FRONT LIFTS NWD THROUGH THE AREA FRIDAY. HOWEVER...STILL LOOKING AT
CAUTIONARY CONDITIONS WITH 15-20KT AND SEAS TO 6FT...POSSIBLY A BIT
HIGHER. COVERAGE OF RAIN AND STORMS/GUSTY WINDS WILL REMAIN MARINE
THREATS INTO SATURDAY. SYNOPTIC GRADIENT WINDS WILL BEGIN TO PICK
BACK UP SAT AFTERNOON AS THE LOW CENTER MOVES OFFSHORE THE FL EAST
COAST AND PGRAD TIGHTENS. SEAS WILL RAMP BACK UP TO 7-10FT OR A
LITTLE HIGHER SAT NIGHT THROUGH SUN AS W-NW WINDS SHIFT TO N AND NNE
BEHIND THE SLOWLY DEPARTING LOW. SLOW IMPROVEMENT IN WINDS SEAS MON.
&&
.PRELIMINARY POINT TEMPS/POPS...
DAB 73 68 78 64 / 20 50 80 60
MCO 79 67 82 66 / 20 50 80 60
MLB 79 71 81 69 / 50 40 70 60
VRB 79 72 81 70 / 50 40 70 60
LEE 78 66 79 61 / 20 50 80 60
SFB 78 67 82 64 / 20 50 80 60
ORL 79 68 82 65 / 20 50 80 60
FPR 80 70 82 72 / 60 40 70 60
&&
.MLB WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
AM...SMALL CRAFT ADVISORY UNTIL 6 AM EDT FRIDAY FOR COASTAL WATERS
FROM FLAGLER BEACH TO VOLUSIA BREVARD COUNTY LINE OUT 20 NM-
COASTAL WATERS FROM VOLUSIA BREVARD COUNTY LINE TO SEBASTIAN
INLET OUT 20 NM-WATERS FROM FLAGLER BEACH TO VOLUSIA BREVARD
COUNTY LINE 20 TO 60 NM OFFSHORE-WATERS FROM VOLUSIA BREVARD
COUNTY LINE TO SEBASTIAN INLET 20 TO 60 NM OFFSHORE.
&&
$$
SHORT TERM/AVIATION...MOSES
LONG TERM....CRISTALDI
AREA FORECAST DISCUSSION
NWS SHREVEPORT LA
418 AM CDT THU APR 17 2014
.DISCUSSION...
OVERALL...NEXT 7 DAYS WILL REMAIN FAIRLY ACTIVE WITH PERSISTENT
RAIN CHANCES BEYOND NEXT WEEKEND...HOWEVER SEVERE WEATHER THREAT
SHOULD BE LOW FOR MUCH OF THE NEXT WEEK. TEMPS WILL CONTINUE TO
GRADUALLY WARM DESPITE THE REPEATED RAIN CHANCES.
TODAY SHOULD BE RAIN FREE UNTIL AFTER 00Z. TWO SHORTWAVE
TROUGHS...ONE CURRENTLY OVER SE CO AND ANOTHER JUST SE OF THE BIG
BEND OF TX WILL MOVE EWD OVER THE NEXT 24 HRS. THE SRN WAVE SHOULD
MOVE WELL S OF THE CWA AND ANY PRECIP SHOULD BE CONFINED MORE
TOWARDS THE GULF COAST. LATEST RUN OF THE HRRR BREAKS OUT SOME
QPF ACROSS DEEP E TX LATER THIS MORNING BUT NONE OF THE OTHER
MODELS ARE REALLY PICKING UP ON THIS. LATEST RADAR LOOPS INDICATE
CONVECTION ACROSS CNTRL TX SHOULD STAY S OF THE CWA. THUS...WILL
KEEP THE DAYTIME HRS DRY. BETTER CHANCES FOR SHWRS WILL LIKELY BE
THIS EVENING AND TONIGHT AS THE CO SHORTWAVE DIVES SE TOWARDS THE
CWA AND EVENTUALLY MERGES WITH THE TX TROUGH OVER THE LOWER MS
VALLEY. WEAK COLD FRONT WILL ALSO MOVE ACROSS THE AREA TONIGHT
WHICH SHOULD PROVIDE A FOCUS FOR A FEW SCT SHWRS. INSTABILITY
LOOKS TO BE QUITE MEAGER SO WILL NOT MENTION THUNDER AT THIS TIME.
FRIDAY AND SATURDAY SHOULD BE DRY AS AN UPPER RIDGE BUILDS OVER
THE AREA. FLOW ALOFT WILL REMAIN PROGRESSIVE THOUGH AND THE RIDGE
SHOULD MOVE E BY SATURDAY EVENING ALLOWING THE FLOW TO TRANSITION
TO SWLY. DEEP LAYER MOISTURE WILL INCREASE WHILE A SERIES OF WEAK
UPPER WAVES MOVE ACROSS THE SRN PLAINS. RAIN CHANCES WILL INCREASE
BEGINNING EARLY SUNDAY AS THE FIRST OF THESE WEAK IMPULSES
APPROACHES AND CONVECTION MOVES INTO THE CWA FROM THE W. BEST
CHANCES FOR SHWRS/TSTMS WILL LIKELY BE LATE SUNDAY AND INTO EARLY
MONDAY MORNING AS AN UPPER TROUGH ARRIVES. CANNOT RULE OUT AN
ISOLATED SEVERE STORM OR TWO BUT INSTABILITY SHOULD BE RATHER LOW
DUE TO THE LOSS OF DAYTIME HEATING SUNDAY NIGHT/MONDAY MORNING.
CHANCES FOR SCT SHWRS/TSTMS WILL PERSIST INTO EARLY NEXT WEEK AS
THE UPPER TROUGH AND COLD FRONT WILL BE VERY SLOW TO PROGRESS.
GFS/ECMWF HAVE BEEN VERY CONSISTENT IN KEEPING RAIN IN THE AREA
UNTIL THE FRONT FINALLY CLEARS THE CWA SO HAVE EXTENDED SLIGHT
CHANCE POPS INTO EARLY TUESDAY MORNING.
AFTER A BRIEF BREAK...ACTIVE PATTERN LOOKS TO CONTINUE AS A MUCH
STRONGER UPPER TROUGH MOVES ACROSS THE COUNTRY LATE NEXT WEEK BUT
IT APPEARS THE TROUGH WILL BE FARTHER N ACROSS THE CNTRL/NRN
PLAINS. STILL...A COLD FRONT AT THE SFC SHOULD STILL PROVIDE AT
LEAST A SLIGHT CHANCE FOR CONVECTION. /09/
&&
.PRELIMINARY POINT TEMPS/POPS...
SHV 70 53 76 57 81 / 10 20 10 10 10
MLU 71 54 74 56 78 / 10 20 10 10 10
DEQ 70 46 77 52 76 / 10 20 10 10 10
TXK 70 51 75 55 78 / 10 20 10 10 10
ELD 70 50 75 54 78 / 10 20 10 10 10
TYR 70 54 75 57 78 / 10 20 10 10 10
GGG 70 53 75 56 78 / 10 20 10 10 10
LFK 71 54 78 57 80 / 10 20 10 10 10
&&
.SHV WATCHES/WARNINGS/ADVISORIES...
AR...NONE.
LA...NONE.
OK...NONE.
TX...NONE.
&&
$$
09/13
AREA FORECAST DISCUSSION
NWS RALEIGH NC
207 AM EDT THU APR 17 2014
.SYNOPSIS...UNSEASONABLY STRONG...POLAR HIGH PRESSURE WILL BUILD
SOUTH FROM NEW ENGLAND TODAY...THEN LINGER THROUGH FRIDAY.
MEANWHILE...LOW PRESSURE WILL DEVELOP OVER THE NORTHEASTERN GULF OF
MEXICO FRIDAY...THEN MEANDER ALONG THE SOUTHEAST US COAST THROUGH
THE WEEKEND.
&&
.NEAR TERM /THROUGH THURSDAY/...
AS OF 1000 PM WEDNESDAY...
PRESSURE READINGS CONTINUE TO RISE ACROSS CENTRAL NC THIS EVENING AS
A STRONG 1036MB SURFACE HIGH OVER NEW ENGLAND REACHES DOWN THE EAST
COAST. THE MAIN STORY FOR THE OVERNIGHT PERIOD IS THE POTENTIAL FOR
FREEZE AND FROST. WINDS HAVE DECOUPLED IN SOME SPOTS...BUT THE
BUILDING SURFACE RIDGE IS KEEPING A LIGHT WIND STIRRING OVER MOST OF
THE AREA. SHOULD SEE MORE AREAS DECOUPLE BY AFTER
MIDNIGHT...ESPECIALLY ACROSS WESTERN AREAS. HOWEVER...THE PRESSURE
GRADIENT IS FORECAST TO TIGHTEN A BIT OVER EASTERN NC BY 09Z IN
RESPONSE TO A WESTWARD MIGRATING INVERTED TROUGH OFFSHORE...AND THE
RATE AT WHICH TEMPS FALL OVER THE COASTAL PLAIN WILL SLOW AS THE
RIDGE AXIS SETTLES TOWARD THE PIEDMONT. COULD ISSUE A FROST
ADVISORY FOR THE COASTAL PLAIN...BUT RAP SOUNDINGS SHOW THE BOUNDARY
LAYER STAYING AT LEAST PARTIALLY MIXED THROUGHOUT THE NIGHT...AND
THE FROST SHOULD REMAIN PATCHY IN NATURE. THE FREEZE WARNING WILL
CONTINUE AS FORECAST. IR SATELLITE IMAGERY SHOWS QUITE A BIT OF
STRATO CU OFFSHORE...WHICH WILL BEGIN TO SPREAD INLAND LATE TONIGHT
AND TOWARD THE I-95 CORRIDOR DURING THE MID-MORNING HOURS ON
THURSDAY. -SMITH
THURSDAY...CIRCULATION AROUND THE LOW LEVEL RIDGE WILL RESULT IN A
LONG NE FETCH OFF THE ATLANTIC INTO EASTERN NC. THIS FLOW WILL
TRANSPORT A SHALLOW THIN LAYER OF MOISTURE INTO THE COASTAL
PLAIN...RESULTING IN A SCATTERED TO BRIEFLY BROKEN LAYER OF STRATOCU
OVER THE COASTAL PLAIN LATER THURSDAY MORNING INTO THURSDAY
AFTERNOON. LAYER TOO SHALLOW TO SUPPORT ANYTHING MORE THAN SPRINKLES
IF EVEN THAT.
TEMPS WILL REMAIN WELL BELOW NORMAL FOR MID APRIL THOUGH SOME
RECOVERY COMPARED TO TODAY ANTICIPATED. AFTERNOON THICKNESSES
PROJECTED TO BE ABOUT 20M WARMT THAN THIS AFTERNOON WHICH SUGGEST
AFTERNOON TEMPS THURSDAY ABOUT 5 DEGREES WARMER THAN THIS AFTERNOON.
THIS IS MORE SIMILAR TO THE COOLER GFS MOS GUIDANCE. MAX TEMPS UPPER
50S TO LOWER 60S.
&&
.SHORT TERM /THURSDAY NIGHT AND FRIDAY /...
AS OF 330 PM WEDNESDAY...
THURSDAY NIGHT AND FRIDAY....SFC RIDGE AXIS WILL LIKELY MAINTAIN ITS
INFLUENCE OVER THE PIEDMONT OF CENTRAL NC THROUGH THIS PERIOD AS
PARENT HIGH BECOMES ANCHORED OVER NORTHERN NEW ENGLAND/CANADIAN
MARITIME DUE TO CONFLUENT FLOW ALOFT. WHILE THE AIR MASS UNDERNEATH
THIS RIDGE WILL GRADUALLY MODIFY...PRESENCE OF DRY AIR UNDER THIS
WEATHER SYSTEM WILL MAINTAIN A BASICALLY CLOUD FREE ATMOSPHERE IN
THE LOWEST 10K FEET. MEANWHILE...A S/W IS PROJECTED TO MOVE EAST-SE
ACROSS THE CENTRAL NC PLAINS AND INTO THE TN VALLEY WHERE IT IS
PROJECTED TO BEGIN TO INTERACT WITH A SYSTEM LIFTING E-NE ACROSS THE
NORTHERN GULF. UPPER LEVEL FLOW OVER THE CAROLINAS WILL BACK IN
RESPONSE TO THE APPROACH OF THESE SYSTEMS...TRANSPORTING HIGH LEVEL
MOISTURE INTO OUR REGION. THIS SHOULD RESULT IN AN INCREASING VEIL
OF HIGH CLOUDS THURSDAY NIGHT INTO FRIDAY. THE THICKNESS OF THESE
HIGH CLOUDS WILL PLAY A ROLE IN WHETHER SCATTERED FROST WILL DEVELOP
OVER THE PIEDMONT THURSDAY NIGHT/EARLY FRIDAY. IN ADDITION...LOW
LEVEL ELY FLOW WILL ADVECT MOISTURE OFF THE ATLANTIC INTO THE
COASTAL PLAIN BY FRIDAY MORNING. MIN TEMPS MID 30S WEST TO UPPER
30S/AROUND 40 EAST.
SHOULD SEE AT A MINIMUM A MIXTURE OF SUN AND CLOUDS FRIDAY WITH THE
CHARACTER OF THE SKY BECOMING MOSTLY CLOUDY OR OVERCAST BY FRIDAY
AFTERNOON. ISENTROPIC UPGLIDE DOES NOT APPEAR STRONG ENOUGH TO
SUPPORT PRECIP FRIDAY AFTERNOON...ASIDE FROM A STRAY SHOWER ACROSS
THE FAR SE.
AIR MASS WILL CONTINUE TO GRADUALLY MODIFY BUT AFTERNOON TEMPS WILL
REMAIN WELL BELOW NORMAL. MAX TEMPS 60-65.
&&
.LONG TERM /FRIDAY NIGHT THROUGH WEDNESDAY/...
AS OF 3 PM WEDNESDAY...
FRIDAY NIGHT THROUGH SUNDAY NIGHT: THE WEEKEND FORECAST CONTINUES TO
HAVE SOME UNCERTAINTY WITH REGARD TO THE EVOLUTION OF A POSSIBLE
CLOSED LOW LINGERING ACROSS THE SOUTHEASTERN U.S/OFFSHORE. WHILE THE
NORTHERN STREAM ENERGY IS PROGRESSIVE AND PUSHES EASTWARD FRIDAY
NIGHT INTO SATURDAY. IN ADVANCE OF THE NORTHERN STREAM TROUGH BOTH
THE 12Z GFS AND ECMWF PULLS MOISTURE NORTHWARD... AND PRODUCED SOME
LIGHT RAIN ACROSS OUR FAR SOUTHEAST/EAST ON FRIDAY NIGHT INTO EARLY
SATURDAY MORNING... WITH THE BULK OF THE PRECIP EXPECTED TO BE TO
OUR EAST AND SOUTH. HOWEVER... MODEL GUIDANCES IS STRUGGLING WITH
WHAT WILL HAPPEN WITH THE LINGERING SOUTHERN STEAM ENERGY THAT
POSSIBLY CLOSES OFF INTO A CLOSED LOW AND LINGERS NEAR FL AND OFF
THE SOUTHEAST U.S. COAST. THE 12Z ECMWF HAS COME A MORE IN THE LINE
WITH THE 12Z GFS IN SHOWING LINGERING MID LEVEL ENERGY SLOWLY
SHIFTING EASTWARD AND FAR ENOUGH AWAY FROM THE COAST TO KEEP US DRY
SATURDAY AFTERNOON THROUGH THE REST OF THE WEEKEND. HOWEVER...
GUIDANCES HAS SHOWN POOR RUN TO RUN CONTINUITY. THUS... CONFIDENCE
IS NOT HIGH THAT LATE SATURDAY INTO SUNDAY THAT WE WILL BE
COMPLETELY DRY AT THIS TIME ACROSS OUR ENTIRE AREA (IF PRECIP
LINGER... LOCATIONS ACROSS THE EAST/SOUTHEAST WOULD SEE THE BEST
CHANCE/MOST). FOR NOW WILL GO WITH A DRY FORECAST AS MENTIONED ABOVE
FROM SATURDAY AFTERNOON ONWARD.
WITH SURFACE HIGH PRESSURE BUILDING INTO THE AREA FROM THE NORTH AND
A COOL EAST TO NORTHEASTERLY LOW LEVEL FLOW EXPECT HIGH TEMPS WILL
REMAIN SLIGHTLY BELOW NORMAL WITH AT LEAST SOME CLOUD COVER (MORE
EAST VS WEST). THUS... WILL GO WITH HIGH TEMPS THIS WEEKEND IN THE
UPPER 60S TO LOWER 70S... WITH LOW TEMPS IN THE 40S TO LOWER 50S.
MONDAY THROUGH WEDNESDAY: NEXT MID LEVEL DISTURBANCE IS EXPECTED TO
CROSS THE REGION ON TUESDAY... ALONG WITH A WEAK SURFACE TROUGH.
HOWEVER... WITH LACK OF ANY SIGNIFICANT MOISTURE RETURN WILL KEEP
POPS LOW AT THIS TIME. TEMPS EARLY TO MID NEXT WEEK ARE EXPECT TO
WARM AGAIN... WITH HIGHS IN THE 70S AND LOWS IN THE 50S.
&&
.AVIATION /06Z THURSDAY THROUGH MONDAY/...
AS OF 200 AM THURSDAY...
UNSEASONABLY STRONG/POLAR HIGH PRESSURE WILL RIDGE SOUTH FROM NEW
ENGLAND AND RESULT IN CLEAR/VFR CONDITIONS THIS MORNING...WHICH WILL
YIELD TO BOTH INCREASING CIRRUS IN SW FLOW ALOFT FROM THE WEST...AND
A BRIEF PERIOD OF SCT TO PERHAPS EVEN BKN STRATOCUMULUS BETWEEN 2500-
4000 FT MAINLY AT EASTERN TERMINALS BETWEEN MID-MORNING THROUGH
EARLY AFTERNOON. THE SURFACE RIDGE WILL ALSO MAINTAIN A
NORTHEASTERLY SURFACE WIND OVER CENTRAL NC...STRONGEST AND
OCCASIONALLY GUSTY INTO THE UPPER TEENS KTS AT EASTERN TERMINALS...
ALSO FROM MID-MORNING TO EARLY AFTERNOON.
OUTLOOK: A LOW PRESSURE SYSTEM WILL DEVELOP AND LINGER OFFSHORE THE
SOUTHEAST US COAST LATE FRI THROUGH THE WEEKEND...AND THIS SYSTEM
MAY RESULT IN RAIN AND SUB-VFR CONDITIONS AT KFAY/KRWI/KRDU FRI
NIGHT-SAT. FORECAST CONFIDENCE REMAINS BELOW AVERAGE REGARDING THE
TRACK OF THE LOW AND ASSOCIATED IMPACTS OVER CENTRAL NC...HOWEVER.
&&
.CLIMATE...
THE FOLLOWING ARE THE RECORD LOW TEMPERATURES FOR THIS MORNING:
THU 04/17
LOW/YEAR
FAY: 31/1953
GSO: 29/1953
RDU: 29/1962
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
FREEZE WARNING FROM MIDNIGHT TONIGHT TO 9 AM EDT THURSDAY FOR
NCZ007>011-021>027-038>041-073>077-083>086.
&&
$$
SYNOPSIS...MWS
NEAR TERM...WSS/SMITH
SHORT TERM...WSS
LONG TERM...BSD
AVIATION...MWS
CLIMATE...MWS
AREA FORECAST DISCUSSION
NWS MOUNT HOLLY NJ
1142 AM EDT THU APR 17 2014
.SYNOPSIS...
HIGH PRESSURE WILL MOVE OUT OF NEW ENGLAND AND ACROSS THE CANADIAN
MARITIMES BUT STILL EXTEND ACROSS THE EASTERN SEABOARD THROUGH EARLY
FRIDAY. A FRONTAL BOUNDARY WILL MOVE ACROSS THE AREA FRIDAY NIGHT
INTO SATURDAY MORNING, BEFORE HIGH PRESSURE REESTABLISHES ITSELF
ACROSS EASTERN CANADA AND BUILDS SOUTHWARD ALONG THE EASTERN SEABOARD
SUNDAY INTO MONDAY. ANOTHER FRONTAL BOUNDARY IS EXPECTED TO AFFECT
THE AREA NEXT TUESDAY, FOLLOWED BY HIGH PRESSURE FOR THE MIDDLE OF
NEXT WEEK.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
NEXT ESTF UPDATE MAINLY FOR AN UPWARD A SKY COVER ADJUSTMENT EAST. WE
FOUND THAT THE RAP IS HANDLING THE 925MB MOISTURE THE BEST. WRF-
NMMB FCST SOUNDINGS ALSO LOOK BETTER THAN THE SOME OF THE PLAN
VIEW MODEL MASS FIELDS. THEY BOTH SHOW SOME DRYING WITH MIXING
LATER IN THE AFTERNOON BEFORE PREDICTED CLOUDS ROLL IN AT NIGHT.
TEMPS IRONICALLY ARE RUNNING TOO LOW VS PREDICTIONS IN SUNNIER
LOCALES FAR NORTH. OVERALL THOUGH NO BIG ADJUSTMENTS MADE THERE.
12Z SOUNDINGS SUPPORT FORECAST MAX TEMPS FOR TODAY.
OTHERWISE...THIS DAY SHOULD BE LOADED WITH SUNSHINE OVER THE
INTERIOR WITH ONLY THIN CIRRUS AT TIMES.
WINDS WILL BE E-NE GUSTING 15 TO 20 MPH AT TIMES.
THE FCST BASIS WAS A 50 50 BLEND 00Z/17 NCEP MOS GUIDANCE.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 AM FRIDAY/...
TONIGHTS FCST WAS ALSO A 50 50 BLEND OF THE 00Z/17 NCEP MOS GUIDANCE.
THAT IN MIND...THE FCST TEMPS ARE GENERALLY FREEZING OR JUST ABOVE.
COLLABORATING THE UNCERTAINTY REGARDING A FREEZE OR A FROST...HAVE
BLENDED THE EARLY FRIDAY MORNING HEADLINE WITH OUR NEIGHBORS. HERE
IN THE MOUNT HOLLY AREA...THINK ODDS FAVOR SLIGHTLY WARMER TEMPS
TONIGHT THAN WHAT OCCURRED THIS THURSDAY MORNING AND SO A FROST APPEARS
MORE LIKELY FROM MY VIEW IN OUR AREA...RATHER THAN A FREEZE BUT
ITS POSSIBLE THE GUIDANCE IS 2 DEGREES TOO WARM?
OTHERWISE THE ONSHORE WIND WILL BE DIMINISHING AND BECOME LIGHT.
ITS POSSIBLE THAT LOW CLOUDS WILL FORM OR HAVE ALREADY FORMED AND
LOCKED INTO PORTIONS OF THE COAST THIS EVENING AND THEN DEVELOP
NWD AS THE BOUNDARY LAYER COOLS....ESPECIALLY CENTRAL NJ. PATCHY
FOG IS ALSO POSSIBLE LATE TONIGHT BUT NOT CURRENTLY IN THE GRIDS.
&&
.LONG TERM /FRIDAY THROUGH WEDNESDAY/...
THE HIGH PRESSURE THAT HAS BEEN EXTENDING SOUTHWARD ACROSS THE EAST
COAST FROM CANADA WILL BEGIN PULLING OUT OF THE AREA DURING THE DAY
FRIDAY. AS THIS HAPPENS, OUR AREA WILL BE IN BETWEEN TWO FEATURES
LATE FRIDAY INTO FRIDAY NIGHT; ONE BEING AN AREA OF LOW PRESSURE TO
OUR SOUTH OFF THE SOUTHEAST COAST AND THE OTHER AN APPROACHING COLD
FRONT. WITH THE PERSISTENT NORTHEAST FLOW ACROSS THE AREA, WE EXPECT
A FAIR AMOUNT OF CLOUD COVER FRIDAY INTO FRIDAY NIGHT. THIS SHOULD
HELP KEEP TEMPERATURES COOL THROUGH THE DAY FRIDAY, SO WE REMAIN
BELOW NORMAL. THE SYSTEM TO OUR SOUTH IS EXPECTED TO REMAIN FAR
ENOUGH TO OUR SOUTH TO PREVENT WIDESPREAD PRECIPITATION TO AFFECT
THE AREA. HOWEVER, THERE REMAINS A SLIGHT CHANCE SOME LIGHT RAIN
ON THE VERY FAR NORTHERN EDGE COULD EXTEND ACROSS OUR SOUTHEASTERN
AREAS, SO WE WILL KEEP SLIGHT CHANCE POPS ACROSS OUR SOUTHEASTERN
ZONES. SOUNDINGS INDICATE THAT THE VERTICAL MOISTURE IS RATHER
SHALLOW, SO IT MAY BE MORE DRIZZLE, SO WE WILL INCLUDE CHANCE
DRIZZLE WITH THE RAIN IN THE FORECAST LATE FRIDAY INTO FRIDAY
NIGHT. THE AFOREMENTIONED COLD FRONT IS EXPECTED TO MOVE THROUGH
THE AREA OVERNIGHT FRIDAY INTO SATURDAY MORNING. ALL GUIDANCE
INDICATES THE PRECIPITATION DRYING OUT AS IT APPROACHES OUR AREA,
SO WE HAVE REMOVED POPS FOR THE REMAINDER OF THE AREA AS WE NOW
EXPECT A DRY FRONTAL PASSAGE.
WE EXPECT DRY WEATHER TO BUILD IN ACROSS THE AREA SATURDAY BEHIND
THE FRONTAL BOUNDARY AS HIGH PRESSURE BEGINS TO BUILD SOUTHWARD OUT
OF CANADA. THE HIGH SHOULD SUPPRESS THE LOW TO OUR SOUTH BY SATURDAY
SO THAT IT WOULDN`T HAVE AN EFFECT ON OUR AREA ANYMORE. THIS HIGH
WILL REESTABLISH ITSELF ACROSS EASTERN CANADA AND BUILDS SOUTHWARD
ALONG THE EASTERN SEABOARD AGAIN INTO SUNDAY AND MONDAY. THIS WILL
CONTINUE TO PROVIDE DRY WEATHER OVER THE WEEKEND INTO MONDAY OF NEXT
WEEK. WITH RIDGING ALOFT TAKING PLACE, TEMPERATURES WILL RETURN
CLOSER TO NORMAL OVER THE WEEKEND INTO EARLY NEXT WEEK.
ON TUESDAY, A COLD FRONT IS FORECAST TO APPROACH THE AREA FROM THE
WEST. AN AREA OF LOW PRESSURE IS FORECAST TO DEVELOP AND STRENGTHEN
ALONG THE BOUNDARY AS IT MOVES ACROSS THE AREA LATE TUESDAY INTO
TUESDAY NIGHT. TUESDAY INTO TUESDAY NIGHT LOOKS TO BE THE NEXT
CHANCE OF PRECIPITATION ACROSS THE AREA. THEREFORE WE HAVE CHANCE
POPS ACROSS THE AREA DURING THIS TIME PERIOD.
THIS LOW IS EXPECTED TO SLOWLY PULL TO OUR NORTHEAST THROUGH
WEDNESDAY AS HIGH PRESSURE BEGINS TO BUILD SOUTHWARD OUT OF CANADA
ONCE AGAIN. WEDNESDAY IS EXPECTED TO BE DRY, BUT SHOULD BE QUITE
GUSTY WITH THE TIGHTENING PRESSURE GRADIENT.
&&
.AVIATION /16Z THURSDAY THROUGH MONDAY/...
THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG, KILG,
KMIV, KACY AND SURROUNDING AREAS.
TODAY...VFR WITH SOME THIN CIRRUS AT TIMES THEN 3500-4000 FT MIDDAY.
MEANWHILE 3000 SCTVBKN DEVELOPING ALONG THE SRN NJ AND DE COAST MAY
BE PREDOMINANT JUST SOUTH OF KACY. CONFIDENCE ON CEILINGS A BIT
BELOW AVG. WIND E-NE WITH GUSTS 15-20 KT BETWEEN 15-21Z.
TONIGHT...PROBABLY VFR TO START BUT MVFR CIGS MAY DEVELOP LATE OR
POSSIBLE EVEN SPOTTY IFR FOG...ESPECIALLY NJ. LIGHT WIND.
CONFIDENCE ON CIGS/VSBY BELOW AVG.
OUTLOOK... FRIDAY-FRIDAY NIGHT...MVFR CIGS POSSIBLE, ESPECIALLY
CLOSER TO THE COAST.
SATURDAY-MONDAY...MOSTLY VFR. GUSTY N-NW WINDS 15-20 KNOTS SATURDAY.
&&
.MARINE...
SCA CONTINUES ATLC WATERS WITH SEAS ALREADY 5 FT AND WINDS/SEAS TO
BUILD A LITTLE TODAY BEFORE SLOWLY SUBSIDING LATER TONIGHT.
ADDED LOWER DE BAY TO THE SCA PER EXPECTED WIND IMPACT AT THE BAY
ENTRANCE.
OUTLOOK...
FRIDAY-FRIDAY NIGHT...SEAS LIKELY TO REMAIN 5 FEET OR GREATER ON THE
OCEAN THROUGH EARLY FRIDAY NIGHT, THEN BEGIN TO SUBSIDE.
SATURDAY...SUB-SMALL CRAFT ADVISORY CRITERIA EXPECTED.
SATURDAY NIGHT-SUNDAY...WINDS AND SEAS INCREASING TO SMALL CRAFT
ADVISORY CRITERIA OVERNIGHT SATURDAY AND CONTINUE INTO SUNDAY,
ESPECIALLY ON OCEAN.
SUNDAY NIGHT-MONDAY...A RETURN TO SUB-SMALL CRAFT ADVISORY CRITERIA
EXPECTED SUNDAY NIGHT.
&&
.PHI WATCHES/WARNINGS/ADVISORIES...
PA...FREEZE WATCH FROM LATE TONIGHT THROUGH FRIDAY MORNING FOR
PAZ060-101>103-106.
NJ...FREEZE WATCH FROM LATE TONIGHT THROUGH FRIDAY MORNING FOR
NJZ012-013-015-017>022-027.
DE...NONE.
MD...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 6 PM EDT FRIDAY FOR ANZ450>455.
SMALL CRAFT ADVISORY UNTIL MIDNIGHT EDT TONIGHT FOR ANZ431.
&&
$$
SYNOPSIS...ROBERTSON
NEAR TERM...DRAG/GIGI
SHORT TERM...DRAG
LONG TERM...ROBERTSON
AVIATION...DRAG/ROBERTSON
MARINE...DRAG/ROBERTSON
AREA FORECAST DISCUSSION
NWS MELBOURNE FL
1025 AM EDT THU APR 17 2014
.DISCUSSION...
...WET THROUGH SATURDAY WITH POTENTIAL FOR LOCALLY HEAVY RAINFALL
ESPECIALLY ALONG THE COAST...
...HAZARDOUS BOATING CONDITIONS THROUGH THIS WEEKEND AND INTO EARLY
NEXT WEEK...
MORNING UPDATE...
STATIONARY BOUNDARY PREVIOUSLY ANALYZED STATIONARY BOUNDARY OVER THE
FLORIDA STRAITS NOW BEING ANALYZED AS A DIFFUSE BOUNDARY APPROACHING
LAKE OKEECHOBEE.
THE BIGGEST CHANGE FOR THE AFTERNOON WILL BE ADDING A SLIGHT CHANCE
OF THUNDERSTORMS TO OKEECHOBEE...MARTIN...SAINT LUCIE...INDIAN RIVER
AND SOUTHERN OSCEOLA COUNTIES WHERE THE AIR MASS WELL BE MORE MOIST
AND ANY BREAKS IN THE SKY COVER WOULD ENHANCE THE INSTABILITY.
MODEL TRENDS ARE INDICATING CAPE VALUES AROUND 1000 JOULES PER
KILOGRAM (J/KG) FOR THE AFTERNOON HOURS. AREA 12Z SOUNDINGS WERE
SHOWING 500MB TEMPERATURES IN THE -12C TO -14C RANGE BUT THE MODELS
WERE SHOWING A LITTLE WARMING TO -10C TO 12C AS THE SOUTHWEST FLOW
ALOFT ADVECTS SLIGHT WARMER AIR INTO CENTRAL FLORIDA. THE TAMPA AND
CAPE CANAVERAL SOUNDINGS WERE SHOWING A WARM LAYER/WEAK CAP BETWEEN
700 AND 600MB THAT COULD HINDER STRONGER STORM DEVELOPMENT OVER THE
AREA TO THE NORTH. ANY CELLS OVER THE SOUTHERN AREAS REACHING HIGH
ENOUGH TO TAP THE COOLER AIR COULD BECOME STRONG ENOUGH TO PRODUCE
GUSTY DOWNBURST WINDS AND LOCALLY HEAVY RAIN LATEST RADAR LOOP WAS
SHOWING ONE AREA OF RAIN MOVING EAST TO WEST OFF THE SOUTHERN
COASTAL WATERS AND INTO SAINT LUCIE AND MARTIN COUNTIES WITH AREAS
OF LIGHT RAIN OVER THE CENTRAL SECTIONS OF EAST CENTRAL FLORIDA.
PREVIOUS DISCUSSION
TODAY-TONIGHT...POST FRONTAL DRY AIRMASS REMAIN FAIRLY PERVASIVE
ACROSS THE REGION...ESPECIALLY ACROSS THE INTERIOR AND VOLUSIA
COUNTY WHERE DEWPOINTS ARE STILL IN THE MID-UPPER 50S.
MODELS HAVE SO FAR BEEN VERY GUNG HO IN LIFTING THE OLD FRONTAL
BOUNDARY/ENHANCED MOISTURE BACK NORTH...BUT IT APPEARS THAT THE
NORTHWARD TREND MAY BE STARTING AS ONE HEAVY RAINBAND SET UP EARLIER
THIS EVENING ACROSS BROWARD COUNTY THAT HAS SINCE DISSIPATED.
CURRENT ANALYSIS SHOWS A BAND OF ENHANCED LOW LEVEL MOISTURE FROM
BREVARD/OSCEOLA COUNTIES SOUTHWARDS COINCIDENT WITH AN AREA OF WIND
CONVERGENCE IN THE 1000-850MB LAYER. THIS IS WHERE RADAR IS ALSO NOW
PICKING UP ON A RECENT UPSWING IN SHOWER COVERAGE.
LOCAL WRF MODEL SHOWS A BAND OF ENHANCED PRECIP AROUND DAYBREAK OVER
THE TREASURE COAST...BUT HRRR MODEL KEEPS THIS ACTIVITY MORE OVER
SOUTH FLORIDA UNTIL LATER. ITS TOUGH TO SAY WHERE OR IF ANY LOCALLY
HEAVY BANDS MAY SET UP UNTIL THEY DO...BUT JUST AHEAD OF/ALONG WARM
FRONT WOULD BE THE BEST BET. DO EXPECT AN INCREASE IN SHOWER
FREQUENCY TOWARDS DAYBREAK ACROSS THE TREASURE COAST.
FRONTAL REMNANTS AND BEST ISENTROPIC LIFT WILL MOVE BACK TO THE
NORTH ACROSS CENTRAL FLORIDA THROUGH THE DAY...ACCELERATING INTO
NORTH FLORIDA TONIGHT AS UPPER LEVEL SHORTWAVE SWINGS EASTWARDS AND
SURFACE LOW DEVELOPS ACROSS THE GULF. HAVE TAPERED BACK RAIN CHANCES
TO 20 PERCENT NORTHERN INTERIOR TO 60 PERCENT OKEECHOBEE/TREASURE
COAST BASED ON CURRENT TRENDS/MODEL FORECAST. COULD SEE A FEW
PERIODS OF HEAVY RAIN ALONG THE COAST TODAY...BEFORE THE BEST RAIN
CHANCES WILL LIFT NORTH OF THE REGION LATER TONIGHT.
THOUGH IT WILL BE BREEZY AGAIN THIS AFTERNOON...IT DOESN`T APPEAR
THAT SPEEDS/GUSTS WILL BE QUITE AS HIGH AS YESTERDAY SO HAVE NOT
ISSUED A LAKE WIND ADVISORY. HOWEVER CONDITIONS WILL STILL REMAIN
CHOPPY ON AREA LAKES.
COASTAL HIGHS WILL BE HIGHLY DEPENDENT ON CLOUD COVER AND PRECIP
TIMING...BUT OVERALL EXPECTED ANYWHERE FROM LOW 70S ALONG VOLUSIA
COAST TO UPPER 70S/AROUND 80 IN BREVARD/TREASURE COAST. INTERIOR
TEMPS IN THE UPPER 70S AND LOW 80S. MILD OVERNIGHT AS FLOW BECOMES
MORE EAST-SOUTHEAST WITH LOWS IN THE UPPER 60S INTERIOR/AROUND 70S
COAST.
FRI-SUN...THE OVERALL TREND OF THE SHORT RANGE FORECAST IS DECIDEDLY
SLOWER AND WETTER INTO SUNDAY. STRONG SOUTHERN STREAM SHORT WAVE
TROUGH WILL MOVE EAST ALONG THE ERN GULF COAST BEFORE PINCHING OFF
INTO A CLOSED MID-UPPER LOW INVOF THE FL/AL/GA TRI-STATE REGION FRI
NIGHT. THE CLOSED LOW WILL THEN DRIFT SLOWLY EAST SOMEWHERE BTWN THE
FL/GA BORDER AND PENINSULAR NORTH FL ON SAT...EASING OFFSHORE SAT
NIGHT AND DRIFTING FARTHER OFFSHORE AND AWAY FROM THE FL EAST COAST
ON SUN.
AT THE SURFACE...AVBL MODEL GUIDANCE HAS CONVERGED TOWARD A MORE
AGREEABLE (SLOWER) SOLUTION...ALTHOUGH THE GFS CONTINUES TO BE THE
FASTEST. SFC FRONTAL WAVE SPINS UP INTO A LOW AND TRACKS ACROSS THE
NERN GOMEX FRI...WITH THE SFC AND MID/UPPER LEVEL LOWS BECOMING
VERTICALLY STACKED BY FRI NIGHT OVER NORTH FL. SFC WARM FRONT LIFTS
NORTHWARD THROUGH CENTRAL FL DURING THE MORNING...WHICH SHOULD TAKE
WIDESPREAD STRATIFORM RAINFALL NWD ACROSS NORTH FL/GA...WHILE ECFL
BREAKS OUT INTO THE WARM SECTOR OF THE GOMEX LOW. DEEP LAYER S-SW
FLOW WITH PWATS AROUND 1.75" WILL LEAD TO WIDESPREAD SHOWERS/STORMS
WITH THE POTENTIAL FOR A BAND OF STRONGER STORMS TO REACH CTRL FL
FROM THE GOMEX (N/W OF I-4) AROUND SUNSET (GIVE OR TAKE) AND
CONTINUE TO DROP SEWD THROUGH THE EVENING HOURS.
SFC LOW WILL BE VERY SLOW TO MOVE ACROSS THE STATE FRI NIGHT...AND
THEN LINGER OFFSHORE THE FL EAST COAST THROUGHOUT SAT. SUFFICIENT
WRAP AROUND MOISTURE WILL EXIST FOR SCT TO NMRS SHOWERS...AND EVEN
SOME STORMS GIVEN THE COLD H50 TEMPS UNDERNEATH THE H50 LOW OVHD.
EXPECT LINGERING SHOWERS SAT NIGHT/SUNDAY IN COOL/MOIST NRLY FLOW
ON BACK SIDE OF THE LOW...WHICH WILL BE GRUDGINGLY SLOW TO PUT SPACE
BETWEEN ITSELF AND FL. COVERAGE/INTENSITY SHOULD BE RATHER LOW.
MON-WED...WEAK HIGH PRESSURE FINALLY SETTLES IN TOWARD FL EARLY NEXT
WEEK...AND DRYING CONDS OUT. THERE ARE SOME SUGGESTIONS OF A WEAK
FRONTAL TROUGH AND ASCD MOISTURE BAND TAKING A GLANCING SHOT AT NORTH
FL TUE-NIGHT INTO WED...BUT WILL NOT GET TOO INVOLVED IN DISSECTING
DAY 6-7 POPS GIVEN THE MORE SIG WX IN DAYS 1-3.
&&
.AVIATION...WARM MOIST SOUTHWEST FLOW MOVING OVERTOP OF A RELATIVELY
COOLER LOW LEVEL AIR MASS BEING ADVECTED EAST TO WEST OFF THE
ATLANTIC WILL PRODUCE HIGHLY VARIABLE CLOUD BASES. NOT STRAYING VERY
FAR FROM THE CURRENT MVFR TAFS FOR THE BALANCE OF THE DAY.
PREVIOUS AVIATION DISCUSSION
MOIST AND CLOUDY THROUGH THE PERIOD...THOUGH OVERALL IT
APPEARS MOST LOCATIONS WILL REMAIN JUST INSIDE VFR WITH PREVAILING
CIGS FL035-050. COASTAL SITES WILL BE MORE LIKELY TO SEE MVFR CIGS
FL020-030. ISOLD SHRA MOVING ONSHORE INTO AREAS SOUTH OF KVRB
THROUGH 13Z...THEN BECOMING SCT-NMRS. COVERAGE WILL INCREASE FROM
SOUTH-NORTH AS OLD FRONTAL BOUNDARY LIFTS BACK TO THE NORTH THROUGH
THE DAY. A FEW HEAVIER SHRA MAY PRODUCE TEMPO IFR CONDITIONS MAINLY
ALONG COASTAL SITES. COULD SEE PREVAILING IFR CIGS LATER TONIGHT AS
WARM FRONT LIFTS NORTH OF REGION.
&&
.MARINE...
CURRENT-THIS AFTERNOON...BUOYS 113...114 AND 009 WERE RECORDING 4 TO
6 FEET NEARSHORE AND 7 FEET AT 20 MILES OFF THE COAST. BUOY 010 OUT
AT 120 MILES OFFSHORE WAS RECORDING 10 FOOT SEAS WITH A 7 FOOT
NORTHEAST SWELL. BOTH BUOYS 009 AND 010 WERE RECORDING NORTHEAST
WINDS AROUND 19 KNOTS WITH GUSTS TO 25 KNOTS. CURRENT AFTERNOON
FORECAST OF WINDS AROUND 20 KNOTS AND 6 TO 9 FOOT SEAS LOOKS GOOD.
SMALL CRAFT ADVISORY FOR ALL MARINE ZONES CONTINUES.
PREVIOUS MARINE DISCUSSION
TODAY-TONIGHT...GUSTY NORTHEAST TO EAST FLOW WILL CONTINUE
TO PRODUCE HAZARDOUS CONDITIONS FOR SMALL CRAFT. PRESSURE GRADIENT
WILL REMAIN STRONGEST OVER WATERS NORTH OF SEBASTIAN INLET...KEEPING
WINDS IN THE 20-25KT RANGE INTO THIS EVENING. WARM FRONT LIFTING
BACK TO THE NORTH WILL EASE GRADIENT FURTHER SOUTH...VEERING WINDS
MORE EAST IN THE 15-20KT RANGE BY LATE MORNING OFF THE TREASURE
COAST. WINDS WILL VEER EAST-SOUTHEAST AND DROP TO 15-20KTS OVER ALL
THE WATERS BY LATE TONIGHT AS THE WARM FRONT LIFTS NORTH OF THE
REGION.
WILL KEEP ADVISORY FOR WINDS/SEAS NORTH OF SEBASTIAN INLET THROUGH
LATE TONIGHT WITH SEAS 5-7FT NEARSHORE/6-9FT OFFSHORE. WILL HAVE
ADVISORY FOR SEAS SOUTH OF SEBASTIAN INLET WHERE WINDS WILL BE
LIGHTER...BUT SEAS WILL BE SIMILAR TO NORTHERN SECTIONS DUE TO
INITIAL NORTHEASTERLY TRAJECTORY.
FRI-MON...A SLIGHT DECREASE IN WINDS/SEAS IS EXPECTED AS THE WARM
FRONT LIFTS NWD THROUGH THE AREA FRIDAY. HOWEVER...STILL LOOKING AT
CAUTIONARY CONDITIONS WITH 15-20KT AND SEAS TO 6FT...POSSIBLY A BIT
HIGHER. COVERAGE OF RAIN AND STORMS/GUSTY WINDS WILL REMAIN MARINE
THREATS INTO SATURDAY. SYNOPTIC GRADIENT WINDS WILL BEGIN TO PICK
BACK UP SAT AFTERNOON AS THE LOW CENTER MOVES OFFSHORE THE FL EAST
COAST AND PGRAD TIGHTENS. SEAS WILL RAMP BACK UP TO 7-10FT OR A
LITTLE HIGHER SAT NIGHT THROUGH SUN AS W-NW WINDS SHIFT TO N AND NNE
BEHIND THE SLOWLY DEPARTING LOW. SLOW IMPROVEMENT IN WINDS SEAS MON.
&&
.PRELIMINARY POINT TEMPS/POPS...
DAB 73 68 78 64 / 20 50 80 60
MCO 79 67 82 66 / 20 50 80 60
MLB 79 71 81 69 / 50 40 70 60
VRB 79 72 81 70 / 50 40 70 60
LEE 78 66 79 61 / 20 50 80 60
SFB 78 67 82 64 / 20 50 80 60
ORL 79 68 82 65 / 20 50 80 60
FPR 80 70 82 72 / 60 40 70 60
&&
.MLB WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
AM...SMALL CRAFT ADVISORY UNTIL 6 AM EDT FRIDAY FOR COASTAL WATERS
FROM FLAGLER BEACH TO VOLUSIA BREVARD COUNTY LINE OUT 20 NM-
COASTAL WATERS FROM VOLUSIA BREVARD COUNTY LINE TO SEBASTIAN
INLET OUT 20 NM-WATERS FROM FLAGLER BEACH TO VOLUSIA BREVARD
COUNTY LINE 20 TO 60 NM OFFSHORE-WATERS FROM VOLUSIA BREVARD
COUNTY LINE TO SEBASTIAN INLET 20 TO 60 NM OFFSHORE.
&&
$$
SHORT TERM/AVIATION...WIMMER
LONG TERM/IMPACT WX...VOLKMER
AREA FORECAST DISCUSSION
NWS GOODLAND KS
704 AM MDT THU APR 17 2014
.UPDATE...
ISSUED AT 702 AM MDT THU APR 17 2014
PLACED FOG IN FOR THIS MORNING OVER THE NORTHWEST PART OF THE
AREA...MAINLY YUMA COUNTY. FOG SHOULD LIFT IN THE NEXT 2 HOURS OR SO.
&&
.SHORT TERM...(TODAY THROUGH SATURDAY NIGHT)
ISSUED AT 421 AM MDT THU APR 17 2014
FORECAST PROBLEMS WILL BE WINDS THROUGH THE PERIOD AND CHANCE OF
PRECIPITATION LATE IN THE PERIOD. SATELLITE SHOWING A SOMEWHAT
AMPLIFIED BUT STILL PROGRESSIVE FLOW FROM THE PACIFIC THROUGH NORTH
AMERICA. STRONG SYSTEM SYSTEM APPROACHING THE PACIFIC NORTHWEST AND
SOUTHWEST CANADA WITH A RIDGE PUSHING IN AHEAD OF IT. AT THIS TIME
THIS IS LEAVING A NORTHWEST FLOW WITH EMBEDDED SHORTWAVE TROUGHS
OVER THE AREA.
AT JET LEVEL...THE NAM WAS DOING A LITTLE BETTER THAN THE GFS. AT MID
LEVELS...OVERALL THE MODELS WERE NOT TOO FAR APART WOULD HAVE TO
GIVE A SLIGHT EDGE TO THE GFS. HOWEVER WITH THE SYSTEM CURRENTLY
PASSING THROUGH THE REGION...THE ECMWF WAS DOING THE BEST. THE
CANADIAN WAS DOING A LITTLE BETTER THAN THE ECMWF...GFS AND NAM ON
THE SURFACE WIND/PRESSURE FIELD. THE GFS WAS DOING A LITTLE BETTER
THAN THE OTHER OUTPUT IN THE LOW LEVEL THERMAL FIELD.
TODAY/TONIGHT...LEFT FRONT QUADRANT STARTS OUT NEAR THE WESTERN END
OF THE AREA AT THE BEGINNING OF THE DAY AND THEN WILL MOVE ACROSS
THE EASTERN HALF DURING THE AFTERNOON...WHICH MEANS IT WILL BE EAST
OF THE AREA AT THE BEGINNING OF THE NIGHT. UPPER SYSTEM WILL
CONTINUE TO AFFECT THE FAR SOUTHERN PORTION OF THE AREA EARLY THIS
MORNING. BASED ON CURRENT RADAR/OBSERVATIONAL TRENDS...SLIGHT
CHANCE TO LOW CHANCE OF PRECIPITATION IN THE FAR SOUTH LOOKS
REASONABLE AND DID NOT ADJUST.
NEXT BUT MINOR CONCERN WILL BE HOW LONG THE CLOUD COVER WILL LAST
THIS MORNING AND IF THAT WILL AFFECT THE HIGH TEMPERATURES. MODELS
NOT DOING A GOOD JOB WITH THE STRATUS WITH RAP DOING THE BEST AND
WILL CONTINUE TO WATCH IT AND OBSERVATIONAL TRENDS TO MAKE ANY
FURTHER ADJUSTMENTS. AS SYSTEM TO OUR SOUTH PULLS OUT...SHOULD GET
A DECENT AMOUNT OF SUBSIDENCE FROM THAT BUT AS MENTIONED ABOVE THE
UPPER JET IS NOT YET TO OUR EAST. DUE TO THE LINGERING CLOUD COVER
AND UNFAVORABLE SURFACE WINDS...ESPECIALLY IN THE EASTERN PORTION...
WILL NOT GET TOO EXCITED ABOUT WARMING TEMPERATURES AND STUCK CLOSE
TO THE PREVIOUS FORECAST.
IF SKY COVER CLEARS AS THE MODELS THINK AND THE GRADIENT
TIGHTENS/PRESSURE FALLS OCCUR AS SURFACE HIGH MOVES EAST AND THE
LEE TROUGH DEVELOPS...WINDS SHOULD GET AT LEAST BREEZY IN THE
WESTERN HALF MAYBE EVEN WINDY. NO HIGHLIGHT WILL BE NEEDED. WINDS
WILL STAY UP TONIGHT AS WARM AIR ADVECTION KICKS IN. MINS WILL BE
WARMER AND MAY NEED TO BE WARMED UP MORE FROM WHAT I HAVE THEM.
FRIDAY/FRIDAY NIGHT...RIDGING ALOFT MOVES IN/THROUGH IN THE FIRST
HALF OF THE DAY WITH FLOW ALOFT TRANSITIONING TO SOUTHWEST IN THE
AFTERNOON. WARMER 850 MB TEMPERATURES AND PLENTY OF SUN WILL ALLOW
FOR A GOOD WARMUP. TENDED TO FOLLOW THE WARMER GUIDANCE.
HOWEVER...THE BIGGER STORY WILL BE THE INCREASING WINDS. GRADIENT
AND 3 HOUR PRESSURE FALLS ARE TIGHTER/LARGER THAN FOR TODAY SO WILL
DEFINITELY SEE A WINDY DAY. SOME OF THE GUIDANCE WOULD SAY WIND
SPEEDS WILL GET NEAR WIND ADVISORY CRITERIA. THIS WILL BE POSSIBLE
DUE TO THE SOUTHWEST FLOW ALOFT DEVELOPING AHEAD OF OUR NEXT STORM
SYSTEM THAT IS MOVING INTO THE DESERT SOUTHWEST. DAY SHIFT WILL
NEED TO LOOK AT THIS CLOSELY AGAIN TO NOT ONLY INCREASE SPEEDS BUT
ALSO AT A POSSIBLE WIND ADVISORY.
LACK OF INSTABILITY AND AN EXTREMELY DEEP DRY LAYER IN THE LOWER
LEVELS OF THE ATMOSPHERE WILL KEEP PRECIPITATION FROM DEVELOPING OR
REACHING THE GROUND DURING THE NIGHT. NO UPPER JET IS CLOSE AND NO
LOW LEVEL JET LOOKS TO BE IN THE AREA. SO REMOVED THE SLIGHT CHANCE
OF PRECIPITATION FROM THE NIGHTTIME PERIOD. WITH WARM AIR AND SOME
MOISTURE ADVECTION STRATUS AND MAYBE SOME FOG MAY DEVELOP/MOVE INTO
THE AREA. SINCE ONLY THE NAM IS SHOWING IT AND THE 06Z NAM PULLED
BACK FROM EARLIER SOLUTION...WILL NOT INCLUDE ANY FOG BUT THE DAY
SHIFT WILL NEED TO TAKE ANOTHER LOOK.
SATURDAY/SATURDAY NIGHT...SPLIT FLOW WILL BE OVER THE AREA THROUGH
THIS PERIOD. THIS IS LEADING TO MAJOR DIFFERENCES IN HOW THE
MODELS HANDLE THE POSITION OF FEATURES AT ALL LEVELS ACROSS THE
AREA. OVERALL THE DETERMINISTIC MODEL CONSENSUS AND ENSEMBLES WERE
SIDING MORE WITH A SLOWER ARRIVING AND FURTHER SOUTHWEST UPPER
TROUGH MOVING IN AND THROUGH THE AREA DURING THIS PERIOD. HOW THE
DETERMINISTIC OUTPUT HANDLED THE MID/UPPER LEVELS AFFECTED HOW
FAST THEY MOVED IN THE FRONT WITH A SIMILAR CONSENSUS AS WHAT WAS
SHOWN FOR THE UPPER LEVELS. THE 06Z NAM SLOWED DOWN FROM THE 00Z
RUN AND MORE CLOSELY RESEMBLED THE ECMWF AND CANADIAN WHICH LOOKED TO
BE HANDLING THE BEHAVIOR OF THE LEE SIDE TROUGH BETTER THAN
EVERYBODY ELSE.
SO DUE TO THE MODEL TRENDS AND ENSEMBLES...SIDED WITH THE SLOWER
AND FURTHER SOUTHWEST UPPER SOLUTION. SO THIS MEANT I PREFERRED
THE SLOWER/FURTHER WEST FRONTAL POSITION FOR THE DAY. SO AHEAD OF
THE FRONT...MOSTLY IN THE SOUTHEAST PORTION...BREEZY TO WINDY
CONDITIONS WILL ONCE AGAIN OCCUR. MORE IMPORTANTLY THE FRONTAL
POSITION WILL DETERMINE WHERE THE BEST CHANCE OF PRECIPITATION WILL
BE. IN ADDITION TO THAT...THE MODELS...DESPITE THE FRONT...TENDED
TO CAP THE LOW LEVELS WITH THE NORTHWEST HALF HAVING THE LEAST AMOUNT
OF CAP. SO BASED ON THE CAP...AND A FURTHER WEST FRONTAL POSITION...
I REDUCED THE CHANCE OF PRECIPITATION AND PUT THE HIGHEST POPS IN
THE NORTHWEST AND CENTRAL POSITION WHERE THE BOUNDARY/BEST LOW LEVEL
CONVERGENCE IS AND WHERE THE CAP IS WEAKEST. ALSO CLOUD COVER IN
ADVANCE OF THIS SYSTEM COULD INHIBIT HEATING AND EXPECTED
INSTABILITY.
TEMPERATURES WILL BE TRICKY DUE TO THE UNCERTAINTY OF THE FRONTAL
POSITION AND ALSO THE AMOUNT OF CLOUD COVER IN ADVANCE OF THE UPPER
STORM SYSTEM. MODELS TENDED TO BE WARMER...ESPECIALLY AHEAD OF THE
FRONT. HOWEVER...DID NOT GO AS WARM AS I COULD DUE TO THE CLOUD
COVER.
BEST TIME FOR PRECIPITATION LOOKS TO ARRIVE DURING THE NIGHT. THE
DEEPEST LIFT ARRIVES DURING THAT TIME AND THE DETERMINISTIC QPF
OUTPUT AND ENSEMBLE PRECIPITATION PROBABILITIES AGREE WITH THAT.
THE SOUTHEAST HALF LOOKS TO HAVE THE BEST CHANCE. SO LEFT THE
PRECIPITATION FORECAST FOR THE NIGHT ALONE. SOMETHING TO WATCH FOR
ONCE THUNDERSTORMS DEVELOP. STORM MOVEMENTS WILL BE SLOW AND NEARLY
PARALLEL TO THE FRONT. SO THERE WILL BE POTENTIAL FOR TRAINING AND
HEAVY RAINFALL.
.LONG TERM...(SUNDAY THROUGH WEDNESDAY)
ISSUED AT 421 AM MDT THU APR 17 2014
SUNDAY THE UPPER LEVEL TROUGH WHICH TRIGGERED CONVECTION SATURDAY
WILL MOVE ACROSS THE AREA WITH THE DRY LINE REMAINING NEAR THE KS/CO
BORDER. AS THE TROUGH MOVES THROUGH...STORMS WILL TURN FROM MOVING
NORTHEAST TO MOVING SOUTH...WHICH WILL INCREASE STORM COVERAGE TO
THE SOUTH OF THE AREA IN THE AFTERNOON. SUNDAY EVENING THE UPPER
LEVEL TROUGH WILL BE EAST OF THE AREA CAUSING RAINFALL TO COME TO AN
END.
MONDAY THE UPPER LEVEL RIDGE WILL MOVE IN BEHIND THE EXITING TROUGH.
WITH A DRY ENVIRONMENT IN PLACE AND NO SHORT WAVE TROUGH MOVING
THROUGH SO WILL KEEP THE DAY DRY.
TUESDAY THE RIDGE WILL STILL BE OVER THE AREA. DURING THE AFTERNOON
A WEAK SHORT WAVE TROUGH WILL MOVE OVER THE AREA. DESPITE THE DRY
LINE STILL REMAINING NEAR THE KS/CO LINE...THE WELL ABOVE NORMAL
TEMPERATURES WILL CAUSE LCLS TO BE VERY HIGH WITH LARGE DEW POINT
DEPRESSIONS AT THE LCL AS WELL. DEW POINT DEPRESSIONS SHRINK BY
LATE AFTERNOON BUT THE SHORT WAVE TROUGH WILL FILL BY THEN. MODEL
CONSENSUS HAS NO RAINFALL FORECAST FOR THE AFTERNOON AS THE TROUGH
MOVES THROUGH. BASED ON THE ABOVE CONSIDERATIONS WILL LEAVE THE
FORECAST DRY...BUT WOULD NOT BE SURPRISED TO SEE AN ISOLATED STORM
OR TWO DEVELOP DURING THE LATTER HALF OF THE AFTERNOON BEFORE THE
SHORT WAVE TROUGH FILLS.
WEDNESDAY A SUBTLE UPPER LEVEL SHORT WAVE TROUGH WILL MOVE ACROSS
THE AREA AS THE DRY LINE IS PUSHED EAST ACROSS THE AREA. THE
ENVIRONMENT WILL BE EVEN DRIER THAN TUESDAY SO A THE DRY FORECAST
WILL CONTINUE FOR THE DAY DESPITE THE DRY LINE MOVING ACROSS THE
AREA.
TUESDAY AND WEDNESDAY A TIGHT SURFACE PRESSURE GRADIENT WILL DEVELOP
AS A SURFACE TROUGH MOVES THROUGH THE AREA LEADING TO WINDY
CONDITIONS. DUE LOW RELATIVE HUMIDITIES MOVING IN BEHIND THE DRY
LINE...HAZARDOUS FIRE WEATHER CONDITIONS MAY DEVELOP OVER PARTS OF
EAST CENTRAL COLORADO TUESDAY AND EXTEND EAST INTO FAR NORTHWEST
KANSAS ON WEDNESDAY.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z FRIDAY MORNING)
ISSUED AT 540 AM MDT THU APR 17 2014
VERY UNCERTAIN FORECAST FOR THE FIRST SIX HOURS SINCE THE MODELS
HAVE ABSOLUTELY NO CLUE ABOUT THE CURRENT STRATUS FIELD IN PLACE
ACROSS OUR AREA. CURRENTLY IFR/NEAR LIFR CONDITIONS AT KGLD AND
MVFR CONDITIONS AT KMCK WITH NO MODEL OUTPUT SHOWING ANYTHING
ANYWHERE CLOSE. SO GO WITH PERSISTENCE AND KEEP THE CURRENT
CONDITIONS GOING THROUGH MOST OF THE MORNING SINCE THE WIND FIELD
IS LIGHT AND DO NOT EXPECT MUCH OF AN AIR MASS CHANGE.
AT THIS TIME BY 18Z DO EXPECT VFR CONDITIONS TO OCCUR AND THOSE
WILL CONTINUE THROUGH THE REST OF THE PERIOD. WINDS WILL BE
SOUTHERLY AT BOTH SITES WITH KGLD BEING GUSTY OFF AND ON THROUGH
THE NIGHT.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
UPDATE...JTL
SHORT TERM...BULLER
LONG TERM...JTL
AVIATION...BULLER
AREA FORECAST DISCUSSION
NWS GOODLAND KS
544 AM MDT THU APR 17 2014
.SHORT TERM...(TODAY THROUGH SATURDAY NIGHT)
ISSUED AT 421 AM MDT THU APR 17 2014
FORECAST PROBLEMS WILL BE WINDS THROUGH THE PERIOD AND CHANCE OF
PRECIPITATION LATE IN THE PERIOD. SATELLITE SHOWING A SOMEWHAT
AMPLIFIED BUT STILL PROGRESSIVE FLOW FROM THE PACIFIC THROUGH NORTH
AMERICA. STRONG SYSTEM SYSTEM APPROACHING THE PACIFIC NORTHWEST AND
SOUTHWEST CANADA WITH A RIDGE PUSHING IN AHEAD OF IT. AT THIS TIME
THIS IS LEAVING A NORTHWEST FLOW WITH EMBEDDED SHORTWAVE TROUGHS
OVER THE AREA.
AT JET LEVEL...THE NAM WAS DOING A LITTLE BETTER THAN THE GFS. AT MID
LEVELS...OVERALL THE MODELS WERE NOT TOO FAR APART WOULD HAVE TO
GIVE A SLIGHT EDGE TO THE GFS. HOWEVER WITH THE SYSTEM CURRENTLY
PASSING THROUGH THE REGION...THE ECMWF WAS DOING THE BEST. THE
CANADIAN WAS DOING A LITTLE BETTER THAN THE ECMWF...GFS AND NAM ON
THE SURFACE WIND/PRESSURE FIELD. THE GFS WAS DOING A LITTLE BETTER
THAN THE OTHER OUTPUT IN THE LOW LEVEL THERMAL FIELD.
TODAY/TONIGHT...LEFT FRONT QUADRANT STARTS OUT NEAR THE WESTERN END
OF THE AREA AT THE BEGINNING OF THE DAY AND THEN WILL MOVE ACROSS
THE EASTERN HALF DURING THE AFTERNOON...WHICH MEANS IT WILL BE EAST
OF THE AREA AT THE BEGINNING OF THE NIGHT. UPPER SYSTEM WILL
CONTINUE TO AFFECT THE FAR SOUTHERN PORTION OF THE AREA EARLY THIS
MORNING. BASED ON CURRENT RADAR/OBSERVATIONAL TRENDS...SLIGHT
CHANCE TO LOW CHANCE OF PRECIPITATION IN THE FAR SOUTH LOOKS
REASONABLE AND DID NOT ADJUST.
NEXT BUT MINOR CONCERN WILL BE HOW LONG THE CLOUD COVER WILL LAST
THIS MORNING AND IF THAT WILL AFFECT THE HIGH TEMPERATURES. MODELS
NOT DOING A GOOD JOB WITH THE STRATUS WITH RAP DOING THE BEST AND
WILL CONTINUE TO WATCH IT AND OBSERVATIONAL TRENDS TO MAKE ANY
FURTHER ADJUSTMENTS. AS SYSTEM TO OUR SOUTH PULLS OUT...SHOULD GET
A DECENT AMOUNT OF SUBSIDENCE FROM THAT BUT AS MENTIONED ABOVE THE
UPPER JET IS NOT YET TO OUR EAST. DUE TO THE LINGERING CLOUD COVER
AND UNFAVORABLE SURFACE WINDS...ESPECIALLY IN THE EASTERN PORTION...
WILL NOT GET TOO EXCITED ABOUT WARMING TEMPERATURES AND STUCK CLOSE
TO THE PREVIOUS FORECAST.
IF SKY COVER CLEARS AS THE MODELS THINK AND THE GRADIENT
TIGHTENS/PRESSURE FALLS OCCUR AS SURFACE HIGH MOVES EAST AND THE
LEE TROUGH DEVELOPS...WINDS SHOULD GET AT LEAST BREEZY IN THE
WESTERN HALF MAYBE EVEN WINDY. NO HIGHLIGHT WILL BE NEEDED. WINDS
WILL STAY UP TONIGHT AS WARM AIR ADVECTION KICKS IN. MINS WILL BE
WARMER AND MAY NEED TO BE WARMED UP MORE FROM WHAT I HAVE THEM.
FRIDAY/FRIDAY NIGHT...RIDGING ALOFT MOVES IN/THROUGH IN THE FIRST
HALF OF THE DAY WITH FLOW ALOFT TRANSITIONING TO SOUTHWEST IN THE
AFTERNOON. WARMER 850 MB TEMPERATURES AND PLENTY OF SUN WILL ALLOW
FOR A GOOD WARMUP. TENDED TO FOLLOW THE WARMER GUIDANCE.
HOWEVER...THE BIGGER STORY WILL BE THE INCREASING WINDS. GRADIENT
AND 3 HOUR PRESSURE FALLS ARE TIGHTER/LARGER THAN FOR TODAY SO WILL
DEFINITELY SEE A WINDY DAY. SOME OF THE GUIDANCE WOULD SAY WIND
SPEEDS WILL GET NEAR WIND ADVISORY CRITERIA. THIS WILL BE POSSIBLE
DUE TO THE SOUTHWEST FLOW ALOFT DEVELOPING AHEAD OF OUR NEXT STORM
SYSTEM THAT IS MOVING INTO THE DESERT SOUTHWEST. DAY SHIFT WILL
NEED TO LOOK AT THIS CLOSELY AGAIN TO NOT ONLY INCREASE SPEEDS BUT
ALSO AT A POSSIBLE WIND ADVISORY.
LACK OF INSTABILITY AND AN EXTREMELY DEEP DRY LAYER IN THE LOWER
LEVELS OF THE ATMOSPHERE WILL KEEP PRECIPITATION FROM DEVELOPING OR
REACHING THE GROUND DURING THE NIGHT. NO UPPER JET IS CLOSE AND NO
LOW LEVEL JET LOOKS TO BE IN THE AREA. SO REMOVED THE SLIGHT CHANCE
OF PRECIPITATION FROM THE NIGHTTIME PERIOD. WITH WARM AIR AND SOME
MOISTURE ADVECTION STRATUS AND MAYBE SOME FOG MAY DEVELOP/MOVE INTO
THE AREA. SINCE ONLY THE NAM IS SHOWING IT AND THE 06Z NAM PULLED
BACK FROM EARLIER SOLUTION...WILL NOT INCLUDE ANY FOG BUT THE DAY
SHIFT WILL NEED TO TAKE ANOTHER LOOK.
SATURDAY/SATURDAY NIGHT...SPLIT FLOW WILL BE OVER THE AREA THROUGH
THIS PERIOD. THIS IS LEADING TO MAJOR DIFFERENCES IN HOW THE
MODELS HANDLE THE POSITION OF FEATURES AT ALL LEVELS ACROSS THE
AREA. OVERALL THE DETERMINISTIC MODEL CONSENSUS AND ENSEMBLES WERE
SIDING MORE WITH A SLOWER ARRIVING AND FURTHER SOUTHWEST UPPER
TROUGH MOVING IN AND THROUGH THE AREA DURING THIS PERIOD. HOW THE
DETERMINISTIC OUTPUT HANDLED THE MID/UPPER LEVELS AFFECTED HOW
FAST THEY MOVED IN THE FRONT WITH A SIMILAR CONSENSUS AS WHAT WAS
SHOWN FOR THE UPPER LEVELS. THE 06Z NAM SLOWED DOWN FROM THE 00Z
RUN AND MORE CLOSELY RESEMBLED THE ECMWF AND CANADIAN WHICH LOOKED TO
BE HANDLING THE BEHAVIOR OF THE LEE SIDE TROUGH BETTER THAN
EVERYBODY ELSE.
SO DUE TO THE MODEL TRENDS AND ENSEMBLES...SIDED WITH THE SLOWER
AND FURTHER SOUTHWEST UPPER SOLUTION. SO THIS MEANT I PREFERRED
THE SLOWER/FURTHER WEST FRONTAL POSITION FOR THE DAY. SO AHEAD OF
THE FRONT...MOSTLY IN THE SOUTHEAST PORTION...BREEZY TO WINDY
CONDITIONS WILL ONCE AGAIN OCCUR. MORE IMPORTANTLY THE FRONTAL
POSITION WILL DETERMINE WHERE THE BEST CHANCE OF PRECIPITATION WILL
BE. IN ADDITION TO THAT...THE MODELS...DESPITE THE FRONT...TENDED
TO CAP THE LOW LEVELS WITH THE NORTHWEST HALF HAVING THE LEAST AMOUNT
OF CAP. SO BASED ON THE CAP...AND A FURTHER WEST FRONTAL POSITION...
I REDUCED THE CHANCE OF PRECIPITATION AND PUT THE HIGHEST POPS IN
THE NORTHWEST AND CENTRAL POSITION WHERE THE BOUNDARY/BEST LOW LEVEL
CONVERGENCE IS AND WHERE THE CAP IS WEAKEST. ALSO CLOUD COVER IN
ADVANCE OF THIS SYSTEM COULD INHIBIT HEATING AND EXPECTED
INSTABILITY.
TEMPERATURES WILL BE TRICKY DUE TO THE UNCERTAINTY OF THE FRONTAL
POSITION AND ALSO THE AMOUNT OF CLOUD COVER IN ADVANCE OF THE UPPER
STORM SYSTEM. MODELS TENDED TO BE WARMER...ESPECIALLY AHEAD OF THE
FRONT. HOWEVER...DID NOT GO AS WARM AS I COULD DUE TO THE CLOUD
COVER.
BEST TIME FOR PRECIPITATION LOOKS TO ARRIVE DURING THE NIGHT. THE
DEEPEST LIFT ARRIVES DURING THAT TIME AND THE DETERMINISTIC QPF
OUTPUT AND ENSEMBLE PRECIPITATION PROBABILITIES AGREE WITH THAT.
THE SOUTHEAST HALF LOOKS TO HAVE THE BEST CHANCE. SO LEFT THE
PRECIPITATION FORECAST FOR THE NIGHT ALONE. SOMETHING TO WATCH FOR
ONCE THUNDERSTORMS DEVELOP. STORM MOVEMENTS WILL BE SLOW AND NEARLY
PARALLEL TO THE FRONT. SO THERE WILL BE POTENTIAL FOR TRAINING AND
HEAVY RAINFALL.
.LONG TERM...(SUNDAY THROUGH WEDNESDAY)
ISSUED AT 421 AM MDT THU APR 17 2014
SUNDAY THE UPPER LEVEL TROUGH WHICH TRIGGERED CONVECTION SATURDAY
WILL MOVE ACROSS THE AREA WITH THE DRY LINE REMAINING NEAR THE KS/CO
BORDER. AS THE TROUGH MOVES THROUGH...STORMS WILL TURN FROM MOVING
NORTHEAST TO MOVING SOUTH...WHICH WILL INCREASE STORM COVERAGE TO
THE SOUTH OF THE AREA IN THE AFTERNOON. SUNDAY EVENING THE UPPER
LEVEL TROUGH WILL BE EAST OF THE AREA CAUSING RAINFALL TO COME TO AN
END.
MONDAY THE UPPER LEVEL RIDGE WILL MOVE IN BEHIND THE EXITING TROUGH.
WITH A DRY ENVIRONMENT IN PLACE AND NO SHORT WAVE TROUGH MOVING
THROUGH SO WILL KEEP THE DAY DRY.
TUESDAY THE RIDGE WILL STILL BE OVER THE AREA. DURING THE AFTERNOON
A WEAK SHORT WAVE TROUGH WILL MOVE OVER THE AREA. DESPITE THE DRY
LINE STILL REMAINING NEAR THE KS/CO LINE...THE WELL ABOVE NORMAL
TEMPERATURES WILL CAUSE LCLS TO BE VERY HIGH WITH LARGE DEW POINT
DEPRESSIONS AT THE LCL AS WELL. DEW POINT DEPRESSIONS SHRINK BY
LATE AFTERNOON BUT THE SHORT WAVE TROUGH WILL FILL BY THEN. MODEL
CONSENSUS HAS NO RAINFALL FORECAST FOR THE AFTERNOON AS THE TROUGH
MOVES THROUGH. BASED ON THE ABOVE CONSIDERATIONS WILL LEAVE THE
FORECAST DRY...BUT WOULD NOT BE SURPRISED TO SEE AN ISOLATED STORM
OR TWO DEVELOP DURING THE LATTER HALF OF THE AFTERNOON BEFORE THE
SHORT WAVE TROUGH FILLS.
WEDNESDAY A SUBTLE UPPER LEVEL SHORT WAVE TROUGH WILL MOVE ACROSS
THE AREA AS THE DRY LINE IS PUSHED EAST ACROSS THE AREA. THE
ENVIRONMENT WILL BE EVEN DRIER THAN TUESDAY SO A THE DRY FORECAST
WILL CONTINUE FOR THE DAY DESPITE THE DRY LINE MOVING ACROSS THE
AREA.
TUESDAY AND WEDNESDAY A TIGHT SURFACE PRESSURE GRADIENT WILL DEVELOP
AS A SURFACE TROUGH MOVES THROUGH THE AREA LEADING TO WINDY
CONDITIONS. DUE LOW RELATIVE HUMIDITIES MOVING IN BEHIND THE DRY
LINE...HAZARDOUS FIRE WEATHER CONDITIONS MAY DEVELOP OVER PARTS OF
EAST CENTRAL COLORADO TUESDAY AND EXTEND EAST INTO FAR NORTHWEST
KANSAS ON WEDNESDAY.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z FRIDAY MORNING)
ISSUED AT 540 AM MDT THU APR 17 2014
VERY UNCERTAIN FORECAST FOR THE FIRST SIX HOURS SINCE THE MODELS
HAVE ABSOLUTELY NO CLUE ABOUT THE CURRENT STRATUS FIELD IN PLACE
ACROSS OUR AREA. CURRENTLY IFR/NEAR LIFR CONDITIONS AT KGLD AND
MVFR CONDITIONS AT KMCK WITH NO MODEL OUTPUT SHOWING ANYTHING
ANYWHERE CLOSE. SO GO WITH PERSISTENCE AND KEEP THE CURRENT
CONDITIONS GOING THROUGH MOST OF THE MORNING SINCE THE WIND FIELD
IS LIGHT AND DO NOT EXPECT MUCH OF AN AIR MASS CHANGE.
AT THIS TIME BY 18Z DO EXPECT VFR CONDITIONS TO OCCUR AND THOSE
WILL CONTINUE THROUGH THE REST OF THE PERIOD. WINDS WILL BE
SOUTHERLY AT BOTH SITES WITH KGLD BEING GUSTY OFF AND ON THROUGH
THE NIGHT.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
SHORT TERM...BULLER
LONG TERM...JTL
AVIATION...BULLER
AREA FORECAST DISCUSSION
NWS GOODLAND KS
421 AM MDT THU APR 17 2014
.SHORT TERM...(TODAY THROUGH SATURDAY NIGHT)
ISSUED AT 421 AM MDT THU APR 17 2014
FORECAST PROBLEMS WILL BE WINDS THROUGH THE PERIOD AND CHANCE OF
PRECIPITATION LATE IN THE PERIOD. SATELLITE SHOWING A SOMEWHAT
AMPLIFIED BUT STILL PROGRESSIVE FLOW FROM THE PACIFIC THROUGH NORTH
AMERICA. STRONG SYSTEM SYSTEM APPROACHING THE PACIFIC NORTHWEST AND
SOUTHWEST CANADA WITH A RIDGE PUSHING IN AHEAD OF IT. AT THIS TIME
THIS IS LEAVING A NORTHWEST FLOW WITH EMBEDDED SHORTWAVE TROUGHS
OVER THE AREA.
AT JET LEVEL...THE NAM WAS DOING A LITTLE BETTER THAN THE GFS. AT MID
LEVELS...OVERALL THE MODELS WERE NOT TOO FAR APART WOULD HAVE TO
GIVE A SLIGHT EDGE TO THE GFS. HOWEVER WITH THE SYSTEM CURRENTLY
PASSING THROUGH THE REGION...THE ECMWF WAS DOING THE BEST. THE
CANADIAN WAS DOING A LITTLE BETTER THAN THE ECMWF...GFS AND NAM ON
THE SURFACE WIND/PRESSURE FIELD. THE GFS WAS DOING A LITTLE BETTER
THAN THE OTHER OUTPUT IN THE LOW LEVEL THERMAL FIELD.
TODAY/TONIGHT...LEFT FRONT QUADRANT STARTS OUT NEAR THE WESTERN END
OF THE AREA AT THE BEGINNING OF THE DAY AND THEN WILL MOVE ACROSS
THE EASTERN HALF DURING THE AFTERNOON...WHICH MEANS IT WILL BE EAST
OF THE AREA AT THE BEGINNING OF THE NIGHT. UPPER SYSTEM WILL
CONTINUE TO AFFECT THE FAR SOUTHERN PORTION OF THE AREA EARLY THIS
MORNING. BASED ON CURRENT RADAR/OBSERVATIONAL TRENDS...SLIGHT
CHANCE TO LOW CHANCE OF PRECIPITATION IN THE FAR SOUTH LOOKS
REASONABLE AND DID NOT ADJUST.
NEXT BUT MINOR CONCERN WILL BE HOW LONG THE CLOUD COVER WILL LAST
THIS MORNING AND IF THAT WILL AFFECT THE HIGH TEMPERATURES. MODELS
NOT DOING A GOOD JOB WITH THE STRATUS WITH RAP DOING THE BEST AND
WILL CONTINUE TO WATCH IT AND OBSERVATIONAL TRENDS TO MAKE ANY
FURTHER ADJUSTMENTS. AS SYSTEM TO OUR SOUTH PULLS OUT...SHOULD GET
A DECENT AMOUNT OF SUBSIDENCE FROM THAT BUT AS MENTIONED ABOVE THE
UPPER JET IS NOT YET TO OUR EAST. DUE TO THE LINGERING CLOUD COVER
AND UNFAVORABLE SURFACE WINDS...ESPECIALLY IN THE EASTERN PORTION...
WILL NOT GET TOO EXCITED ABOUT WARMING TEMPERATURES AND STUCK CLOSE
TO THE PREVIOUS FORECAST.
IF SKY COVER CLEARS AS THE MODELS THINK AND THE GRADIENT
TIGHTENS/PRESSURE FALLS OCCUR AS SURFACE HIGH MOVES EAST AND THE
LEE TROUGH DEVELOPS...WINDS SHOULD GET AT LEAST BREEZY IN THE
WESTERN HALF MAYBE EVEN WINDY. NO HIGHLIGHT WILL BE NEEDED. WINDS
WILL STAY UP TONIGHT AS WARM AIR ADVECTION KICKS IN. MINS WILL BE
WARMER AND MAY NEED TO BE WARMED UP MORE FROM WHAT I HAVE THEM.
FRIDAY/FRIDAY NIGHT...RIDGING ALOFT MOVES IN/THROUGH IN THE FIRST
HALF OF THE DAY WITH FLOW ALOFT TRANSITIONING TO SOUTHWEST IN THE
AFTERNOON. WARMER 850 MB TEMPERATURES AND PLENTY OF SUN WILL ALLOW
FOR A GOOD WARMUP. TENDED TO FOLLOW THE WARMER GUIDANCE.
HOWEVER...THE BIGGER STORY WILL BE THE INCREASING WINDS. GRADIENT
AND 3 HOUR PRESSURE FALLS ARE TIGHTER/LARGER THAN FOR TODAY SO WILL
DEFINITELY SEE A WINDY DAY. SOME OF THE GUIDANCE WOULD SAY WIND
SPEEDS WILL GET NEAR WIND ADVISORY CRITERIA. THIS WILL BE POSSIBLE
DUE TO THE SOUTHWEST FLOW ALOFT DEVELOPING AHEAD OF OUR NEXT STORM
SYSTEM THAT IS MOVING INTO THE DESERT SOUTHWEST. DAY SHIFT WILL
NEED TO LOOK AT THIS CLOSELY AGAIN TO NOT ONLY INCREASE SPEEDS BUT
ALSO AT A POSSIBLE WIND ADVISORY.
LACK OF INSTABILITY AND AN EXTREMELY DEEP DRY LAYER IN THE LOWER
LEVELS OF THE ATMOSPHERE WILL KEEP PRECIPITATION FROM DEVELOPING OR
REACHING THE GROUND DURING THE NIGHT. NO UPPER JET IS CLOSE AND NO
LOW LEVEL JET LOOKS TO BE IN THE AREA. SO REMOVED THE SLIGHT CHANCE
OF PRECIPITATION FROM THE NIGHTTIME PERIOD. WITH WARM AIR AND SOME
MOISTURE ADVECTION STRATUS AND MAYBE SOME FOG MAY DEVELOP/MOVE INTO
THE AREA. SINCE ONLY THE NAM IS SHOWING IT AND THE 06Z NAM PULLED
BACK FROM EARLIER SOLUTION...WILL NOT INCLUDE ANY FOG BUT THE DAY
SHIFT WILL NEED TO TAKE ANOTHER LOOK.
SATURDAY/SATURDAY NIGHT...SPLIT FLOW WILL BE OVER THE AREA THROUGH
THIS PERIOD. THIS IS LEADING TO MAJOR DIFFERENCES IN HOW THE
MODELS HANDLE THE POSITION OF FEATURES AT ALL LEVELS ACROSS THE
AREA. OVERALL THE DETERMINISTIC MODEL CONSENSUS AND ENSEMBLES WERE
SIDING MORE WITH A SLOWER ARRIVING AND FURTHER SOUTHWEST UPPER
TROUGH MOVING IN AND THROUGH THE AREA DURING THIS PERIOD. HOW THE
DETERMINISTIC OUTPUT HANDLED THE MID/UPPER LEVELS AFFECTED HOW
FAST THEY MOVED IN THE FRONT WITH A SIMILAR CONSENSUS AS WHAT WAS
SHOWN FOR THE UPPER LEVELS. THE 06Z NAM SLOWED DOWN FROM THE 00Z
RUN AND MORE CLOSELY RESEMBLED THE ECMWF AND CANADIAN WHICH LOOKED TO
BE HANDLING THE BEHAVIOR OF THE LEE SIDE TROUGH BETTER THAN
EVERYBODY ELSE.
SO DUE TO THE MODEL TRENDS AND ENSEMBLES...SIDED WITH THE SLOWER
AND FURTHER SOUTHWEST UPPER SOLUTION. SO THIS MEANT I PREFERRED
THE SLOWER/FURTHER WEST FRONTAL POSITION FOR THE DAY. SO AHEAD OF
THE FRONT...MOSTLY IN THE SOUTHEAST PORTION...BREEZY TO WINDY
CONDITIONS WILL ONCE AGAIN OCCUR. MORE IMPORTANTLY THE FRONTAL
POSITION WILL DETERMINE WHERE THE BEST CHANCE OF PRECIPITATION WILL
BE. IN ADDITION TO THAT...THE MODELS...DESPITE THE FRONT...TENDED
TO CAP THE LOW LEVELS WITH THE NORTHWEST HALF HAVING THE LEAST AMOUNT
OF CAP. SO BASED ON THE CAP...AND A FURTHER WEST FRONTAL POSITION...
I REDUCED THE CHANCE OF PRECIPITATION AND PUT THE HIGHEST POPS IN
THE NORTHWEST AND CENTRAL POSITION WHERE THE BOUNDARY/BEST LOW LEVEL
CONVERGENCE IS AND WHERE THE CAP IS WEAKEST. ALSO CLOUD COVER IN
ADVANCE OF THIS SYSTEM COULD INHIBIT HEATING AND EXPECTED
INSTABILITY.
TEMPERATURES WILL BE TRICKY DUE TO THE UNCERTAINTY OF THE FRONTAL
POSITION AND ALSO THE AMOUNT OF CLOUD COVER IN ADVANCE OF THE UPPER
STORM SYSTEM. MODELS TENDED TO BE WARMER...ESPECIALLY AHEAD OF THE
FRONT. HOWEVER...DID NOT GO AS WARM AS I COULD DUE TO THE CLOUD
COVER.
BEST TIME FOR PRECIPITATION LOOKS TO ARRIVE DURING THE NIGHT. THE
DEEPEST LIFT ARRIVES DURING THAT TIME AND THE DETERMINISTIC QPF
OUTPUT AND ENSEMBLE PRECIPITATION PROBABILITIES AGREE WITH THAT.
THE SOUTHEAST HALF LOOKS TO HAVE THE BEST CHANCE. SO LEFT THE
PRECIPITATION FORECAST FOR THE NIGHT ALONE. SOMETHING TO WATCH FOR
ONCE THUNDERSTORMS DEVELOP. STORM MOVEMENTS WILL BE SLOW AND NEARLY
PARALLEL TO THE FRONT. SO THERE WILL BE POTENTIAL FOR TRAINING AND
HEAVY RAINFALL.
.LONG TERM...(SUNDAY THROUGH WEDNESDAY)
ISSUED AT 421 AM MDT THU APR 17 2014
SUNDAY THE UPPER LEVEL TROUGH WHICH TRIGGERED CONVECTION SATURDAY
WILL MOVE ACROSS THE AREA WITH THE DRY LINE REMAINING NEAR THE KS/CO
BORDER. AS THE TROUGH MOVES THROUGH...STORMS WILL TURN FROM MOVING
NORTHEAST TO MOVING SOUTH...WHICH WILL INCREASE STORM COVERAGE TO
THE SOUTH OF THE AREA IN THE AFTERNOON. SUNDAY EVENING THE UPPER
LEVEL TROUGH WILL BE EAST OF THE AREA CAUSING RAINFALL TO COME TO AN
END.
MONDAY THE UPPER LEVEL RIDGE WILL MOVE IN BEHIND THE EXITING TROUGH.
WITH A DRY ENVIRONMENT IN PLACE AND NO SHORT WAVE TROUGH MOVING
THROUGH SO WILL KEEP THE DAY DRY.
TUESDAY THE RIDGE WILL STILL BE OVER THE AREA. DURING THE AFTERNOON
A WEAK SHORT WAVE TROUGH WILL MOVE OVER THE AREA. DESPITE THE DRY
LINE STILL REMAINING NEAR THE KS/CO LINE...THE WELL ABOVE NORMAL
TEMPERATURES WILL CAUSE LCLS TO BE VERY HIGH WITH LARGE DEW POINT
DEPRESSIONS AT THE LCL AS WELL. DEW POINT DEPRESSIONS SHRINK BY
LATE AFTERNOON BUT THE SHORT WAVE TROUGH WILL FILL BY THEN. MODEL
CONSENSUS HAS NO RAINFALL FORECAST FOR THE AFTERNOON AS THE TROUGH
MOVES THROUGH. BASED ON THE ABOVE CONSIDERATIONS WILL LEAVE THE
FORECAST DRY...BUT WOULD NOT BE SURPRISED TO SEE AN ISOLATED STORM
OR TWO DEVELOP DURING THE LATTER HALF OF THE AFTERNOON BEFORE THE
SHORT WAVE TROUGH FILLS.
WEDNESDAY A SUBTLE UPPER LEVEL SHORT WAVE TROUGH WILL MOVE ACROSS
THE AREA AS THE DRY LINE IS PUSHED EAST ACROSS THE AREA. THE
ENVIRONMENT WILL BE EVEN DRIER THAN TUESDAY SO A THE DRY FORECAST
WILL CONTINUE FOR THE DAY DESPITE THE DRY LINE MOVING ACROSS THE
AREA.
TUESDAY AND WEDNESDAY A TIGHT SURFACE PRESSURE GRADIENT WILL DEVELOP
AS A SURFACE TROUGH MOVES THROUGH THE AREA LEADING TO WINDY
CONDITIONS. DUE LOW RELATIVE HUMIDITIES MOVING IN BEHIND THE DRY
LINE...HAZARDOUS FIRE WEATHER CONDITIONS MAY DEVELOP OVER PARTS OF
EAST CENTRAL COLORADO TUESDAY AND EXTEND EAST INTO FAR NORTHWEST
KANSAS ON WEDNESDAY.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z THURSDAY NIGHT)
ISSUED AT 1030 PM MDT WED APR 16 2014
KGLD...VFR CONDITIONS EXPECTED BEFORE 11Z AND AFTER 15Z. HAVE
INTRODUCED MVFR CIGS IN THE 11Z-15Z TIME FRAME AS STRATUS MOVES
DOWN FROM THE NORTH/NORTHEAST (WHERE CIGS CURRENTLY MVFR). A
WEATHER DISTURBANCE CURRENTLY ALONG THE COLORADO FRONT RANGE IS
FORECAST TO MOVE EAST/SOUTHEAST TONIGHT EXITING THE AREA BEFORE
18Z THURSDAY. EAST WINDS AROUND 6KTS AT TAF ISSUANCE FORECAST TO
VEER TO THE SOUTHEAST BY 11Z THURSDAY. DURING THE AFTERNOON HOURS
SOUTH/SOUTHEAST WINDS OF 12-17KTS WITH GUSTS AROUND 25KTS
EXPECTED.
KMCK...VFR CONDITIONS EXPECTED BEFORE 08Z AND AFTER 12Z. HAVE
INTRODUCED MVFR CIGS IN THE 08Z-12Z TIME FRAME AS STRATUS MOVES
DOWN FROM THE NORTH/NORTHEAST. SIMILAR SYNOPTIC SCENARIO AS KGLD.
NORTHEAST WINDS AROUND 10KTS AT TAF ISSUANCE TO BECOME EASTERLY BY
14Z THEN SOUTHEAST AND SOUTH/SOUTHEAST AFTER 18Z AND THROUGH THE
REST OF THE TAF PERIOD.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
SHORT TERM...BULLER
LONG TERM...JTL
AVIATION...DDT
AREA FORECAST DISCUSSION
NWS SHREVEPORT LA
1033 AM CDT THU APR 17 2014
.DISCUSSION...
SHORT WAVE NEAR COAST CREATING CONVECTION OVER GULF...WITH SHOWERS
MOVG NEWD ONSHORE...BUT WEAKENING AS THEY MOVE INTO MORE STABLE
AIRMASS...AS SEEN ON 12Z LCH RAOB. ADDED ISOLD SHOWERS TO FCST FOR
THIS AFTN...TO SOUTHERN PORTIONS TO ACCOUNT FOR SHOWERS TRYING TO
WORK THEIR WAY FROM THE SOUTH. TEMPERATURES HAVE BEEN STEADILY
CLIMBING DESPITE THICKENING MID LVL CLOUDINESS...SO FOR NOW...WILL STILL
EXPECT AFTN TEMPS TO REACH UPPER 60S TO AROUND 70./VII/
&&
.PREV DISCUSSION... /ISSUED 418 AM CDT THU APR 17 2014/
DISCUSSION...
OVERALL...NEXT 7 DAYS WILL REMAIN FAIRLY ACTIVE WITH PERSISTENT
RAIN CHANCES BEYOND NEXT WEEKEND...HOWEVER SEVERE WEATHER THREAT
SHOULD BE LOW FOR MUCH OF THE NEXT WEEK. TEMPS WILL CONTINUE TO
GRADUALLY WARM DESPITE THE REPEATED RAIN CHANCES.
TODAY SHOULD BE RAIN FREE UNTIL AFTER 00Z. TWO SHORTWAVE
TROUGHS...ONE CURRENTLY OVER SE CO AND ANOTHER JUST SE OF THE BIG
BEND OF TX WILL MOVE EWD OVER THE NEXT 24 HRS. THE SRN WAVE SHOULD
MOVE WELL S OF THE CWA AND ANY PRECIP SHOULD BE CONFINED MORE
TOWARDS THE GULF COAST. LATEST RUN OF THE HRRR BREAKS OUT SOME
QPF ACROSS DEEP E TX LATER THIS MORNING BUT NONE OF THE OTHER
MODELS ARE REALLY PICKING UP ON THIS. LATEST RADAR LOOPS INDICATE
CONVECTION ACROSS CNTRL TX SHOULD STAY S OF THE CWA. THUS...WILL
KEEP THE DAYTIME HRS DRY. BETTER CHANCES FOR SHWRS WILL LIKELY BE
THIS EVENING AND TONIGHT AS THE CO SHORTWAVE DIVES SE TOWARDS THE
CWA AND EVENTUALLY MERGES WITH THE TX TROUGH OVER THE LOWER MS
VALLEY. WEAK COLD FRONT WILL ALSO MOVE ACROSS THE AREA TONIGHT
WHICH SHOULD PROVIDE A FOCUS FOR A FEW SCT SHWRS. INSTABILITY
LOOKS TO BE QUITE MEAGER SO WILL NOT MENTION THUNDER AT THIS TIME.
FRIDAY AND SATURDAY SHOULD BE DRY AS AN UPPER RIDGE BUILDS OVER
THE AREA. FLOW ALOFT WILL REMAIN PROGRESSIVE THOUGH AND THE RIDGE
SHOULD MOVE E BY SATURDAY EVENING ALLOWING THE FLOW TO TRANSITION
TO SWLY. DEEP LAYER MOISTURE WILL INCREASE WHILE A SERIES OF WEAK
UPPER WAVES MOVE ACROSS THE SRN PLAINS. RAIN CHANCES WILL INCREASE
BEGINNING EARLY SUNDAY AS THE FIRST OF THESE WEAK IMPULSES
APPROACHES AND CONVECTION MOVES INTO THE CWA FROM THE W. BEST
CHANCES FOR SHWRS/TSTMS WILL LIKELY BE LATE SUNDAY AND INTO EARLY
MONDAY MORNING AS AN UPPER TROUGH ARRIVES. CANNOT RULE OUT AN
ISOLATED SEVERE STORM OR TWO BUT INSTABILITY SHOULD BE RATHER LOW
DUE TO THE LOSS OF DAYTIME HEATING SUNDAY NIGHT/MONDAY MORNING.
CHANCES FOR SCT SHWRS/TSTMS WILL PERSIST INTO EARLY NEXT WEEK AS
THE UPPER TROUGH AND COLD FRONT WILL BE VERY SLOW TO PROGRESS.
GFS/ECMWF HAVE BEEN VERY CONSISTENT IN KEEPING RAIN IN THE AREA
UNTIL THE FRONT FINALLY CLEARS THE CWA SO HAVE EXTENDED SLIGHT
CHANCE POPS INTO EARLY TUESDAY MORNING.
AFTER A BRIEF BREAK...ACTIVE PATTERN LOOKS TO CONTINUE AS A MUCH
STRONGER UPPER TROUGH MOVES ACROSS THE COUNTRY LATE NEXT WEEK BUT
IT APPEARS THE TROUGH WILL BE FARTHER N ACROSS THE CNTRL/NRN
PLAINS. STILL...A COLD FRONT AT THE SFC SHOULD STILL PROVIDE AT
LEAST A SLIGHT CHANCE FOR CONVECTION. /09/
&&
.PRELIMINARY POINT TEMPS/POPS...
SHV 70 53 76 57 81 / 10 20 10 10 10
MLU 71 54 74 56 78 / 10 20 10 10 10
DEQ 70 46 77 52 76 / 10 20 10 10 10
TXK 70 51 75 55 78 / 10 20 10 10 10
ELD 70 50 75 54 78 / 10 20 10 10 10
TYR 70 54 75 57 78 / 10 20 10 10 10
GGG 70 53 75 56 78 / 10 20 10 10 10
LFK 71 54 78 57 80 / 10 20 10 10 10
&&
.SHV WATCHES/WARNINGS/ADVISORIES...
AR...NONE.
LA...NONE.
OK...NONE.
TX...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS TWIN CITIES/CHANHASSEN MN
601 AM CDT THU APR 17 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 414 AM CDT THU APR 17 2014
EARLY THIS MORNING...WEAKENING SURFACE LOW WAS MOVING EAST NEAR LA
CROSSE, WI. THIS LOW WILL RAPIDLY WEAKEN AS IT MOVES ACROSS
WISCONSIN TODAY...BUT NORTH TO NORTHWEST WINDS ACROSS MINNESOTA WILL
REMAIN BLUSTERY EARLY THIS MORNING BEFORE THE WEAKENING PRESSURE
GRADIENT ALLOWS THEM TO SUBSIDE SOME. A MIX OF RAIN AND SNOW ACROSS
WEST CENTRAL WISCONSIN EARLY THIS MORNING WILL QUICKLY DISSIPATE AND
MOVE EAST OVER THE NEXT FEW HOURS. THE TOUGH PART OF THIS FORECAST
PERIOD INCLUDES PREDICTING THE EXTENT OF THE STRATUS DECK
TODAY...AND THE MAX TEMPERATURES TODAY CONSIDERING ALL THE FRESH
SNOW COVER AND THE PESKY LOW CLOUDS. THE CLOUD COVER LOOKS TO LINGER
ACROSS EAST CENTRAL MN THROUGH SOUTH CENTRAL MN...AND WEST CENTRAL
WI...WHILE WESTERN AND NORTHWESTERN MN REMAIN PARTLY CLOUDY. LOWERED
TEMPERATURES SLIGHTLY FROM MOST GUIDANCE ACROSS THE SNOW PACK...BUT
DIDN`T GO TOO CRAZY WITH THAT BECAUSE IT IS MID APRIL AND DEEP
MIXING CAN STILL OCCUR IN THIS SITUATION. OTHERWISE...SURFACE RIDGE
OF HIGH PRESSURE BUILDS IN THIS AFTERNOON AND WINDS BECOME CALM THIS
EVENING UNDER THE RIDGE AXIS...ANOTHER COOL NIGHT IS FORECAST WITH
SUB-FREEZING TEMPERATURES EXPECTED ACROSS THE FORECAST AREA.
.LONG TERM...(FRIDAY THROUGH WEDNESDAY)
ISSUED AT 414 AM CDT THU APR 17 2014
SURFACE RIDGING WILL PUSH EAST EARLY FRIDAY WITH SOUTHEASTERLY
WIND INCREASING THROUGH THE DAY. A WARM FRONT PUSHING NORTHEAST
INTO FAR SOUTHWESTERN MN MAY KICK OFF A FEW SHOWERS OVER CENTRAL
AND WESTERN MN. MODELS HAVE BEEN TRENDING DRIER WITH THE MOST
RECENT NAM NOW ALMOST COMPLETELY DRY. MAINTAINED SLIGHT CHANCE
POPS...BUT THEY COULD BE REMOVED IN FUTURE FORECASTS. CLOUD COVER
WILL BE EXTENSIVE IN STRONG WAA ENVIRONMENT...AND WHEN COUPLED
WITH INCREASING SOUTHEASTERLY WIND AND RESIDUAL SNOW COVER...WILL
BRING A CHILLY DAY WITH HIGHS IN THE 40S...EXCEPT SOME 50S NEAR
THE IOWA BORDER DEPENDING HOW FAR NORTH THE FRONT CAN LIFT DURING
THE DAY. TEMPERATURES WILL DROP OFF FRIDAY EVENING BEFORE BECOMING
STEADY OR SLOWLY RISE OVERNIGHT FOLLOWING THE PASSAGE OF THE WARM
FRONT.
LOW PRESSURE WILL TREK NORTH ACROSS THE DAKOTAS INTO SOUTHERN
MANITOBA SATURDAY. A COLD FRONT WILL STRETCH TO THE SOUTH INTO THE
MIDWEST AND EASTERN PLAINS...BUT FORCING WILL BE WEAK WITH MUCH OF
THE ENERGY BEING DEFLECTED TO THE NORTH. NOT PARTICULARLY EXCITED
ABOUT SHOWER CHANCES SATURDAY...BUT THEY WILL BE BEST ACROSS
CENTRAL MN. IF SOME SUN CAN BREAK THROUGH...HIGHS WILL REACH THE
60S WHICH COULD TAP ENOUGH ELEVATED INSTABILITY FOR A LOW
PROBABILITY OF THUNDER.
THE FRONT WILL SLOW SATURDAY NIGHT...EVENTUALLY WASHING OUT ACROSS
THE GREAT LAKES AND MID MISSOURI VALLEY SUNDAY. SHOWER CHANCES
WILL LINGER NEAR THIS FRONT ACROSS SERN MN AND WRN WI. THE REST OF
THE REGION WILL SEE CLEARING SKIES. MILD PACIFIC AIR WILL PUSH
ACROSS THE PLAINS DURING THIS TIME AND PLENTIFUL SUNSHINE IN MUCH
OF MN WILL BRING TEMPS BACK INTO THE 60S OR LOW 70S.
THERMAL RIDGING ARRIVES MONDAY AS 925 MB TEMPS RISE INTO THE +14
TO +16C RANGE. MIXING TO 850 MB WILL TAKE FULL ADVANTAGE OF THIS
THERMAL RIDGING AND TEMPS WILL CLIMB INTO THE MID 60S TO MID 70S.
AS STRONG LOW PRESSURE DEVELOPS OVER THE NORTHERN ROCKIES BY MID
WEEK...THE WARM FRONT WILL RETREAT AND WINDS WILL BACK
EASTERLY/SOUTHEASTERLY. THIS WILL MARK A TREND TOWARD COOLER TEMPS
AT LEAST TEMPORARILY MIDWEEK...PARTICULARLY AS A BAND OF SHOWERS
AND THUNDERSTORMS DEVELOP NORTH OF THE BOUNDARY. VERY WARM AND
HUMID AIR IN THE WARM SECTOR WILL TRY TO MAKE AN APPEARANCE BY
THURSDAY PENDING THE TRACK OF THE LOW. THIS WILL BRING INCREASING
SEVERE WEATHER CHANCES...WHICH BEARS WATCHING.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z FRIDAY MORNING)
ISSUED AT 554 AM CDT THU APR 17 2014
WE`LL STILL SEE CYCLONIC FLOW ACROSS EASTERN MINNESOTA AND WESTERN
WISCONSIN THROUGH MUCH OF THE DAY...SO THE QUESTION IS HOW LONG
WILL THE LOW STRATUS LINGER...WHICH IS A TOUGH FORECAST AS I
BELIEVE THE HI-RES MODELS ARE BEING TOO PESSIMISTIC IN THIS CASE.
SO...EXPECTING CEILINGS TO SLOWLY RAISE THIS MORNING AS THE
SURFACE WARMS...AND SCATTER OUT THIS AFTERNOON AS THE SURFACE
RIDGE PUSHES IN FROM THE WEST...AND THE CYCLONIC FLOW MOVES
FURTHER TO THE EAST. OTHERWISE A DRY FORECAST PERIOD WITH
NORTHWEST WINDS BECOMING LIGHT AND VARIABLE THIS EVENING UNDER THE
RIDGE.
KMSP...GOING AGAINST THE RAP WHICH IS PESSIMISTIC IN SCATTERING
CLOUDS OUT AS IT WANTS TO HOLD ON TO THE STRATUS UNTIL THIS
EVENING. THINKING DRY AIR ADVECTING IN AND SURFACE RIDGE WILL
SCATTER OUT THE STRATUS FASTER (BY THE AFTERNOON).
/OUTLOOK FOR KMSP/
FRI...MAINLY VFR. CHC MVFR FRI NIGHT WITH -RA. WINDS NE 5-10 KTS.
SAT...MAINLY VFR. CHC MVFR WITH -RA. WINDS ESE 10-15 KTS.
SUN...VFR. WINDS NNE 5-10 KTS.
&&
.MPX WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...WINTER WEATHER ADVISORY UNTIL 7 AM CDT THIS MORNING FOR WIZ025-
027.
WINTER STORM WARNING UNTIL 7 AM CDT THIS MORNING FOR WIZ015-016.
&&
$$
SHORT TERM...SPD
LONG TERM...BORGHOFF
AVIATION...SPD
AREA FORECAST DISCUSSION...UPDATED AVIATION
NWS ST LOUIS MO
652 AM CDT Thu Apr 17 2014
.SHORT TERM: (Through Tonight)
Issued at 300 AM CDT Thu Apr 17 2014
A weak cold front will move into the area today and could serve as
the focus for scattered light rain showers during the afternoon
and evening. Convergence along the front is not very impressive
and the low levels are somewhat dry, but the combination of
increasing large scale ascent ahead of an approaching vort max
along with the presence of a surface boundary merits slight chance
to chance PoPs.
Kanofsky
.LONG TERM: (Tomorrow through Wednesday)
Issued at 300 AM CDT Thu Apr 17 2014
For the last 4 nights in a row, no two consecutive 00z runs of the
ECMWF/GFS/GEM have had the same solution for upcoming frontal
systems, and there has also been a fair amount of variability
between models regarding the location of important features such as
upper vorticity maxima and surface boundaries. The latest runs keep
a strong vort max and its surface low up near the US/Canada border
on Fri night and Sat, therefore precipitation is no longer expected
with this system across the LSX CWA. The dominant feature for
Fri-Sat now appears to be ridging. Winds should eventually turn
southerly, bringing warmer air into the region for Sat and
reinforcing a baroclinic zone extending from the US/Canada system
as it starts to occlude. A broad trough moving through the desert
southwest could bring precipitation to the area on Sun/Mon. Chance
PoPs remain an acceptable compromise in light of the model
uncertainty. Confidence remains low in the forecast for this
weekend and beyond.
Kanofsky
&&
.AVIATION: (For the 12z TAFs through 12z Friday Morning)
Issued at 638 AM CDT Thu Apr 17 2014
Weak cold front currently on the door step of KCOU and KUIN will
drift east today, and not reach the STL metro area until 21-00z
time frame. Post frontal band of MVFR SC with bases 1-2kft has
worked into northern Missouri, and over the last few hours higher
clouds have obscured their movement on satellite imagery. However,
surface ob trends as well as RUC low level RH progs suggest that
this cloud deck will reach KUIN shortly, and then dissipate by
mid-late morning. With this expected trend, cloud deck should
remain n of KCOU, and not threaten STL area. Otherwise, cloud
trends today and into this evening should be dominated by a
thickening mid deck with bases aoa 5kft. We are expecting a few
post frontal showers, but given the hit and miss coverage that is
anticipated have not included in TAFS at this time.
Specifics for KSTL: Weak cold front currently over mid MO not
expected to reach the area until the 21-23z time frame, with winds
shifting slowly to the northwest once fropa occurs. Otherwise,
looking for a gradual increase in mid clouds over the area, with
bases remaining aoa 5kft. A few showers are possible in the
evening, but as mentioned in the primary aviation discussion have
omitted from this TAF set due to the spotty nature of the precip.
Truett
&&
.LSX WATCHES/WARNINGS/ADVISORIES:
MO...NONE.
IL...NONE.
&&
$$
WFO LSX
AREA FORECAST DISCUSSION
NWS WILMINGTON OH
1153 AM EDT THU APR 17 2014
.SYNOPSIS...
WARMER TEMPERATURES WILL RETURN TODAY AS SOUTHERLY FLOW DEVELOPS AROUND
HIGH PRESSURE TO OUR NORTHEAST. A WEAK COLD FRONT WILL CROSS OUR REGION
ON FRIDAY...BRINGING A LOW END CHANCE FOR SHOWERS TO THE AREA. HIGH
PRESSURE WILL BRING FAIR WEATHER AND SEASONABLY WARM TEMPERATURES
TO THE REGION THIS WEEKEND.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
THE LATEST RAP MODEL...COMPARED TO THE 12Z KILN SOUNDING...SEEMS
TO BE HANDLING THE OVERALL MOISTURE PROFILE ACROSS THE REGION THIS
MORNING. ALSO...IT IS MIXING THE AIRMASS THROUGH 850 MB BY LATE
AFTN. THIS DEEPER MIXING...ALONG WITH MOSTLY SUNNY SKIES...WILL
YIELD TEMPERATURES A LITTLE WARMER THAN PREVIOUSLY FORECAST. HIGHS
SHOULD RANGE FROM THE MID 60S NORTH TO AROUND 70 NEAR AND SOUTH OF
THE OHIO RIVER.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH FRIDAY NIGHT/...
WEAK LOW PRESSURE WILL CROSS THE NORTHERN GREAT LAKES TONIGHT. A
COLD FRONT EXTENDING SOUTHWARD FROM THIS LOW WILL APPROACH OUR
AREA OVERNIGHT...AND WILL BE LOCATED ACROSS NORTHERN IN/IL BY
DAYBREAK FRIDAY. THE HIGH ACROSS NEW ENGLAND TODAY WILL HAVE MOVED
OFFSHORE BY TONIGHT. THIS WILL RESULT IN A WEAKENING SURFACE
GRADIENT AND LIGHT WINDS OVERNIGHT. THE AIRMASS THAT WILL BE IN
PLACE WILL BE DRY...WITH SURFACE DEWPOINTS EXPECTED TO BE IN THE
30S. SKIES WILL START OFF MOSTLY CLEAR...WITH A GRADUALLY INCREASE
IN CLOUDS FROM WEST TO EAST OVERNIGHT AHEAD OF THE WEAK COLD
FRONT. THE COMBINATION OF DRY AIR AT THE SURFACE...LIGHT
WINDS...AND MOSTLY CLEAR SKIES TO START OFF TONIGHT WILL RESULT IN
TEMPERATURES DROPPING INTO THE 40S. SOME LOCATIONS EAST OF
COLUMBUS MAY DROP INTO THE 30S WITH A LONGER PERIOD OF MOSTLY
CLEAR SKIES EXPECTED THERE.
THE WEAK FRONT WILL ARRIVE IN OUR AREA FROM THE NORTHWEST ON
FRIDAY. MODELS CONTINUE TO TREND TOWARD WEAKENING THIS MOISTURE
STARVED FRONT AS IT MOVES INTO OUR AREA. SHOWERS ARE FORECAST TO
DEVELOP ALONG THE FRONT FRIDAY JUST WEST OF OUR AREA.
HOWEVER...THESE SHOWERS ARE FORECAST TO LESSEN IN COVERAGE AND
WEAKEN AS THEY TRY TO PUSH ACROSS THE AREA FRIDAY AFTERNOON.
ALSO...IT NOW APPEARS THAT THE FRONT WILL BE LOSING ITS
CHARACTERISTICS FRIDAY AFTERNOON AS THE ASSOCIATED LOW LIFTS
NORTHEASTWARD FROM OUR REGION....AND THE CANADIAN HIGH BEHIND THE
LOW FAILS TO BUILD TOO FAR SOUTH INTO THE OHIO VALLEY. ALL OF
THESE FACTORS DO NOT BODE WELL FOR ANY DECENT POPS...AND THE CHANCE
POPS ACROSS OUR NORTHERN ZONES MAY BE GENEROUS FOR THIS FRONT.
HIGHS ON FRIDAY AHEAD OF THE FRONT WILL RISE ONCE AGAIN INTO THE
60S ACROSS ALL ZONES. THE ONLY DIFFERENCE IN TEMPERATURES FRIDAY
COMPARED TO TODAY MAY BE THE SLIGHTLY COOLER LOWER 60S EXPECTED
ACROSS THE NORTH DUE TO THE PROXIMITY OF THE WEAK COLD FRONT.
500-1000 HPA HEIGHTS WILL BEGIN TO BUILD ACROSS THE REGION ON
SATURDAY. HIGH PRESSURE OFF TO THE NORTH WILL PROVIDE
NORTHEASTERLY SURFACE WINDS. THE COUNTERACTING NATURE OF THE
HEIGHT RISES AND NORTHEASTERLY WINDS WILL PRODUCE YET ANOTHER DAY
OF MID TO UPPER 60S ACROSS THE SOUTH ON SATURDAY. ACROSS THE
NORTH...THE NORTHEASTERLY WINDS SHOULD KEEP TEMPERATURES FROM
RISING MUCH ABOVE 60 AS COOLER AIR IS DRAWN ACROSS THOSE ZONES
FROM LAKE ERIE.
SOUTHERLY SURFACE FLOW WILL DEVELOP ON SUNDAY AS THE HIGH TO OUR
NORTH SHIFTS TO OUR NORTHEAST. THE COMBINATION OF THE RETURN FLOW
AND BUILDING 500-1000 HPA HEIGHTS WILL RESULT IN HIGHS IN THE 70S
ACROSS MOST OF THE AREA...WITH PERHAPS A FEW UPPER 60S ACROSS THE
NORTH.
&&
.LONG TERM /SATURDAY THROUGH WEDNESDAY/...
HIGH PRESSURE STRETCHING FROM SOUTHEAST CANADA THROUGH THE GREAT
LAKES AND OHIO VALLEY WILL KEEP DRY WEATHER OVER THE AREA SATURDAY
AND SUNDAY. A COLD FRONT WILL ENTER THE REGION MONDAY. GFS AND
ECMWF BOTH INDICATE THE FRONT...BUT DIFFERENCES IN TIMING
EXIST...WITH GFS FASTER AND ECMWF OFFERING A SLOWER SOLUTION.
SPLIT THE DIFFERENCE BETWEEN MODELS AND WENT WITH A MODEL
BLEND...WHICH YIELDS THE LIKELIHOOD FOR SHOWERS MONDAY AND MONDAY
NIGHT. WITH MODELS SHOWING SCANT INSTABILITY AND RATHER WEAK WIND
FIELDS ALONG THE FRONT...DECIDED TO OMIT THUNDER. HIGH PRESSURE
AND DRY AIR ARE EXPECTED TO RETURN FOR TUESDAY AND WEDNESDAY.
TEMPERATURES WILL START OUT A BIT COOL ON SATURDAY WITH HIGHS
FORECAST TO BE IN THE UPPER 50S TO MID 60S. DUE TO A MODEST AMOUNT
OF WARM ADVECTION...HIGHS FOR SUNDAY THROUGH WEDNESDAY ARE
ANTICIPATED TO AVERAGE IN THE NEAR NORMAL MID AND UPPER 60S.
&&
.AVIATION /16Z THURSDAY THROUGH MONDAY/...
RETURN FLOW PATTERN IN PLACE ACROSS THE REGION THROUGH THIS
AFTERNOON WILL PROVIDE FOR PRIMARILY JUST SOME HIGH LEVEL
CLOUDINESS. A WEAK FRONT WILL APPROACH THE AREA FROM THE NORTHWEST
TONIGHT. MOISTURE IS FAIRLY LIMITED AHEAD OF THE FRONT SO JUST
EXPECT AN INCREASE IN SOME LOWER VFR CLOUDS TONIGHT.
OUTLOOK...MVFR CEILINGS AND VISIBILITIES ARE POSSIBLE MONDAY.
&&
.ILN WATCHES/WARNINGS/ADVISORIES...
OH...NONE.
KY...NONE.
IN...NONE.
&&
$$
SYNOPSIS...HICKMAN/LATTO
NEAR TERM...HICKMAN/LATTO
SHORT TERM...LATTO
LONG TERM...CONIGLIO
AVIATION...JGL
AREA FORECAST DISCUSSION...UPDATED
NWS FORT WORTH TX
1057 AM CDT THU APR 17 2014
.UPDATE...
SATELLITE IMAGERY AND UPPER AIR ANALYSIS SHOWS A DISTURBANCE
MOVING INTO THE TEXAS PANHANDLE AT THIS HOUR. LOW CLOUDS CONTINUE
TO SPREAD NORTH AHEAD OF THIS DISTURBANCE AND DRIZZLE/LIGHT RAIN IS
BEING REPORTED UNDERNEATH THESE LOW CLOUDS AT SEVERAL SITES ACROSS
THE SOUTHERN HALF OF THE CWA. LIGHT RETURNS ON AREA RADARS SHOW
THE LIGHT RAIN/DRIZZLE MOVING NORTH TOWARDS THE I-20 CORRIDOR. WEAK
LIFT COMBINED WITH INCREASING MOISTURE WILL ALLOW SCATTERED
SHOWERS TO DEVELOP ACROSS THE REGION TODAY. THIS AFTERNOON...THE
CONCENTRATION OF RAIN MAY BECOME MORE FOCUSED NEAR A COLD FRONT
MOVING TOWARDS OUR NORTHWESTERN COUNTIES. INCREASED POPS FOR THE
REMAINDER OF THE DAY TO 30 PERCENT ACROSS THE REGION WITH 40 POPS
IN THE NORTHWEST QUADRANT THIS AFTERNOON. FORECAST SOUNDINGS
CONTINUE TO SHOW A WELL CAPPED ENVIRONMENT THROUGH THE DAY AND
KEPT THUNDER OUT OF THE FORECAST.
OTHERWISE...EXPECT OVERCAST TO MOSTLY CLOUDY SKIES FOR MOST OF THE
DAY. LOWERED DAYTIME HIGHS A FEW DEGREES DUE TO THE CLOUD COVER.
82/JLD
&&
.AVIATION...
LATEST RAP AND 12Z NAM SHOWING SIGNIFICANTLY MORE DRY AIR IN THE
LOWER LEVELS THAN PREVIOUSLY FORECAST. HAVE AMENDED TAFS TO
INCREASE CIGS HEIGHTS TODAY AND TONIGHT ABOVE 2000FT. THESE MVFR
CIGS WILL STILL MOVE INTO THE AREA FROM THE SOUTH BY LATE
MORNING...WITH SOME CHANCE OF LIGHT DRIZZLE OR BR THIS AFTERNOON.
IF PRECIPITATION IS ENOUGH TO SATURATE THE LOWER LEVELS CIGS MAY
DROP BELOW 2000FT. THIS POTENTIAL IS GREATER OVER TARRANT COUNTY
THAN IN DALLAS COUNTY...SO THIS WILL NEED TO BE MONITORED.
TR.92
&&
.PREV DISCUSSION... /ISSUED 400 AM CDT THU APR 17 2014/
EARLY MORNING SURFACE ANALYSIS INDICATED A LOW PRESSURE SYSTEM
ACROSS SOUTHEAST MINNESOTA WITH A COLD FRONT TRAILING SOUTHWARD
INTO THE SOUTHERN PLAINS ACROSS NORTH CENTRAL OKLAHOMA AND INTO
THE TEXAS PANHANDLE. THIS FRONT WILL SAG SOUTHWARD A LITTLE
FARTHER THROUGH THE DAY BUT IS NOT EXPECTED TO MOVE THROUGH NORTH
TEXAS. ACROSS OUR PART OF THE STATE...SOUTHERLY FLOW HAS HELPED
TRANSPORT LOW LEVEL MOISTURE NORTHWARD...RESULTING IN INCREASING
CLOUD COVER AND WARMER TEMPERATURES. SOME SCATTERED CONVECTION
DEVELOPED OVER CENTRAL TEXAS OVER THE LAST COUPLE OF HOURS WHICH
IS A BIT SURPRISING GIVEN THE EXPECTED THERMODYNAMIC PROFILE
ACROSS THE REGION. 00Z SOUNDING DATA AND 7Z MODEL ANALYSIS
INDICATE A STRONGLY CAPPED ENVIRONMENT WITH MOISTURE CONFINED
GENERALLY BELOW 800MB. THE MODEL ANALYSIS CLEARLY APPEARS TO BE IN
ERROR AS THE ATMOSPHERE WOULD HAVE TO BE MODIFIED SIGNIFICANTLY TO
GET CONVECTION. WATER VAPOR IMAGERY DOES SHOW A FAIRLY STRONG
SHORTWAVE MOVING THROUGH WEST TEXAS...AHEAD OF THE MAIN
DISTURBANCE WHICH IS A LITTLE FARTHER WEST. CAPPING INVERSION IS
LIKELY MUCH WEAKER ACROSS CENTRAL TEXAS...AT LEAST IMMEDIATELY
DOWNSTREAM OF THE APPROACHING SHORTWAVE...WHERE LIFT IS SUFFICIENT
TO OVERCOME ANY REMAINING INHIBITION. DESPITE THE POOR MODEL
PERFORMANCE DOWNSTREAM OF THIS LEAD SHORTWAVE...THINK THE
CONVECTION SHOULD BE CONFINED WELL SOUTH OF OUR AREA THROUGH THE
MORNING AND WILL LIKELY WEAKEN AS IT PROGRESSES FARTHER EAST.
ACROSS OUR AREA TODAY...CLOUDY SKIES WILL PREVAIL WITH
TEMPERATURES IN THE UPPER 60S. LIFT FROM THE MAIN DISTURBANCE WILL
INCREASE LATER TODAY...BUT STRONG CAPPING IS EXPECTED TO REMAIN IN
PLACE WITH ANY PRECIPITATION EXPECTED TO BE LIGHT SHOWERS BENEATH
THE CAP. BEST CHANCES WILL BE THIS AFTERNOON ACROSS THE NORTHWEST
COUNTIES CLOSER TO THE SURFACE BOUNDARY AND BETTER LIFT TO THE
NORTH. THIS SYSTEM MOVES EAST BY TONIGHT BUT LEAVES BEHIND AMPLE
LOW LEVEL MOISTURE.
FRIDAY AND SATURDAY SHOULD BE DRY WITH TEMPERATURES WARMING INTO
THE UPPER 70S AND LOWER 80S BENEATH RIDGING ALOFT. BY SATURDAY
NIGHT ANOTHER DISTURBANCE MOVES OUT OF THE SOUTHWEST U.S. AND
SPREADS ASCENT ACROSS NORTH TEXAS. CONVECTION SHOULD DEVELOP
INITIALLY ACROSS WEST TEXAS LATE SATURDAY NIGHT AND MOVE EAST WITH
TIME. BEST CHANCES FOR SHOWERS AND THUNDERSTORMS ACROSS NORTH
TEXAS APPEARS TO BE DURING THE DAY SUNDAY WHEN LIFT FROM THE UPPER
TROUGH IS STRONGEST. AMPLE HEATING SUNDAY AFTERNOON WILL LEAD TO
SURFACE BASED CAPE IN EXCESS OF 1500J/KG ACROSS MUCH OF THE AREA.
WIND FIELDS ARE GENERALLY WEAK ALTHOUGH DEEP LAYER SHEAR WILL
INCREASE WITH THE APPROACH OF THE UPPER TROUGH SUNDAY AFTERNOON.
THERE WILL BE THE POTENTIAL FOR SOME STRONG TO MARGINALLY SEVERE
STORMS SUNDAY AFTERNOON. UPPER TROUGH WILL CONTINUE TO PROVIDE AT
LEAST SOME LIFT ACROSS NORTH TEXAS SUNDAY NIGHT INTO EARLY MONDAY
WHEN A WEAK FRONT APPROACHES THE AREA. RAISED POPS SUNDAY NIGHT
AND ADDED SOME LOW POPS ACROSS THE AREA FOR EARLY MONDAY.
BEYOND MONDAY...IT LOOKS DRY AT LEAST THROUGH MIDWEEK UNDER RIDING
ALOFT WITH MORE ACTIVE WEATHER TOWARD THE END OF NEXT WEEK.
DUNN
&&
.PRELIMINARY POINT TEMPS/POPS...
DALLAS-FT. WORTH, TX 66 57 77 61 79 / 30 20 10 10 10
WACO, TX 68 54 76 55 79 / 30 20 10 10 10
PARIS, TX 66 50 75 55 77 / 30 20 10 10 10
DENTON, TX 66 53 75 56 78 / 40 20 10 10 10
MCKINNEY, TX 66 52 75 56 78 / 30 20 10 10 10
DALLAS, TX 66 57 77 61 80 / 30 20 10 10 10
TERRELL, TX 68 53 75 58 78 / 30 20 10 10 10
CORSICANA, TX 66 54 77 59 79 / 30 20 10 10 10
TEMPLE, TX 68 55 77 57 79 / 30 20 10 10 10
MINERAL WELLS, TX 68 58 74 57 79 / 40 20 10 10 10
&&
.FWD WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
92/82
AREA FORECAST DISCUSSION
NWS FORT WORTH TX
1013 AM CDT THU APR 17 2014
.AVIATION...
LATEST RAP AND 12Z NAM SHOWING SIGNIFICANTLY MORE DRY AIR IN THE
LOWER LEVELS THAN PREVIOUSLY FORECAST. HAVE AMENDED TAFS TO
INCREASE CIGS HEIGHTS TODAY AND TONIGHT ABOVE 2000FT. THESE MVFR
CIGS WILL STILL MOVE INTO THE AREA FROM THE SOUTH BY LATE
MORNING...WITH SOME CHANCE OF LIGHT DRIZZLE OR BR THIS AFTERNOON.
IF PRECIPITATION IS ENOUGH TO SATURATE THE LOWER LEVELS CIGS MAY
DROP BELOW 2000FT. THIS POTENTIAL IS GREATER OVER TARRANT COUNTY
THAN IN DALLAS COUNTY...SO THIS WILL NEED TO BE MONITORED.
TR.92
&&
.PREV DISCUSSION... /ISSUED 400 AM CDT THU APR 17 2014/
EARLY MORNING SURFACE ANALYSIS INDICATED A LOW PRESSURE SYSTEM
ACROSS SOUTHEAST MINNESOTA WITH A COLD FRONT TRAILING SOUTHWARD
INTO THE SOUTHERN PLAINS ACROSS NORTH CENTRAL OKLAHOMA AND INTO
THE TEXAS PANHANDLE. THIS FRONT WILL SAG SOUTHWARD A LITTLE
FARTHER THROUGH THE DAY BUT IS NOT EXPECTED TO MOVE THROUGH NORTH
TEXAS. ACROSS OUR PART OF THE STATE...SOUTHERLY FLOW HAS HELPED
TRANSPORT LOW LEVEL MOISTURE NORTHWARD...RESULTING IN INCREASING
CLOUD COVER AND WARMER TEMPERATURES. SOME SCATTERED CONVECTION
DEVELOPED OVER CENTRAL TEXAS OVER THE LAST COUPLE OF HOURS WHICH
IS A BIT SURPRISING GIVEN THE EXPECTED THERMODYNAMIC PROFILE
ACROSS THE REGION. 00Z SOUNDING DATA AND 7Z MODEL ANALYSIS
INDICATE A STRONGLY CAPPED ENVIRONMENT WITH MOISTURE CONFINED
GENERALLY BELOW 800MB. THE MODEL ANALYSIS CLEARLY APPEARS TO BE IN
ERROR AS THE ATMOSPHERE WOULD HAVE TO BE MODIFIED SIGNIFICANTLY TO
GET CONVECTION. WATER VAPOR IMAGERY DOES SHOW A FAIRLY STRONG
SHORTWAVE MOVING THROUGH WEST TEXAS...AHEAD OF THE MAIN
DISTURBANCE WHICH IS A LITTLE FARTHER WEST. CAPPING INVERSION IS
LIKELY MUCH WEAKER ACROSS CENTRAL TEXAS...AT LEAST IMMEDIATELY
DOWNSTREAM OF THE APPROACHING SHORTWAVE...WHERE LIFT IS SUFFICIENT
TO OVERCOME ANY REMAINING INHIBITION. DESPITE THE POOR MODEL
PERFORMANCE DOWNSTREAM OF THIS LEAD SHORTWAVE...THINK THE
CONVECTION SHOULD BE CONFINED WELL SOUTH OF OUR AREA THROUGH THE
MORNING AND WILL LIKELY WEAKEN AS IT PROGRESSES FARTHER EAST.
ACROSS OUR AREA TODAY...CLOUDY SKIES WILL PREVAIL WITH
TEMPERATURES IN THE UPPER 60S. LIFT FROM THE MAIN DISTURBANCE WILL
INCREASE LATER TODAY...BUT STRONG CAPPING IS EXPECTED TO REMAIN IN
PLACE WITH ANY PRECIPITATION EXPECTED TO BE LIGHT SHOWERS BENEATH
THE CAP. BEST CHANCES WILL BE THIS AFTERNOON ACROSS THE NORTHWEST
COUNTIES CLOSER TO THE SURFACE BOUNDARY AND BETTER LIFT TO THE
NORTH. THIS SYSTEM MOVES EAST BY TONIGHT BUT LEAVES BEHIND AMPLE
LOW LEVEL MOISTURE.
FRIDAY AND SATURDAY SHOULD BE DRY WITH TEMPERATURES WARMING INTO
THE UPPER 70S AND LOWER 80S BENEATH RIDGING ALOFT. BY SATURDAY
NIGHT ANOTHER DISTURBANCE MOVES OUT OF THE SOUTHWEST U.S. AND
SPREADS ASCENT ACROSS NORTH TEXAS. CONVECTION SHOULD DEVELOP
INITIALLY ACROSS WEST TEXAS LATE SATURDAY NIGHT AND MOVE EAST WITH
TIME. BEST CHANCES FOR SHOWERS AND THUNDERSTORMS ACROSS NORTH
TEXAS APPEARS TO BE DURING THE DAY SUNDAY WHEN LIFT FROM THE UPPER
TROUGH IS STRONGEST. AMPLE HEATING SUNDAY AFTERNOON WILL LEAD TO
SURFACE BASED CAPE IN EXCESS OF 1500J/KG ACROSS MUCH OF THE AREA.
WIND FIELDS ARE GENERALLY WEAK ALTHOUGH DEEP LAYER SHEAR WILL
INCREASE WITH THE APPROACH OF THE UPPER TROUGH SUNDAY AFTERNOON.
THERE WILL BE THE POTENTIAL FOR SOME STRONG TO MARGINALLY SEVERE
STORMS SUNDAY AFTERNOON. UPPER TROUGH WILL CONTINUE TO PROVIDE AT
LEAST SOME LIFT ACROSS NORTH TEXAS SUNDAY NIGHT INTO EARLY MONDAY
WHEN A WEAK FRONT APPROACHES THE AREA. RAISED POPS SUNDAY NIGHT
AND ADDED SOME LOW POPS ACROSS THE AREA FOR EARLY MONDAY.
BEYOND MONDAY...IT LOOKS DRY AT LEAST THROUGH MIDWEEK UNDER RIDING
ALOFT WITH MORE ACTIVE WEATHER TOWARD THE END OF NEXT WEEK.
DUNN
&&
.PRELIMINARY POINT TEMPS/POPS...
DALLAS-FT. WORTH, TX 68 57 77 61 79 / 20 20 10 10 10
WACO, TX 70 54 76 55 79 / 20 20 10 10 10
PARIS, TX 67 50 75 55 77 / 10 20 10 10 10
DENTON, TX 67 53 75 56 78 / 30 20 10 10 10
MCKINNEY, TX 67 52 75 56 78 / 20 20 10 10 10
DALLAS, TX 69 57 77 61 80 / 20 20 10 10 10
TERRELL, TX 70 53 75 58 78 / 20 20 10 10 10
CORSICANA, TX 71 54 77 59 79 / 20 20 10 10 10
TEMPLE, TX 70 55 77 57 79 / 20 20 10 10 10
MINERAL WELLS, TX 67 58 74 57 79 / 30 20 10 10 10
&&
.FWD WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
/
AREA FORECAST DISCUSSION
NWS MOUNT HOLLY NJ
615 PM EDT THU APR 17 2014
.SYNOPSIS...
A RIDGE OF HIGH PRESSURE WILL REMAIN ACROSS THE FORECAST AREA
TONIGHT THROUGH FRIDAY NIGHT. A COLD FRONT WILL CROSS THE REGION
FRIDAY NIGHT. MORE HIGH PRESSURE WILL BUILD DOWN FROM CANADA AND
REMAIN ACROSS THE AREA THIS WEEKEND AND INTO MONDAY NIGHT. ANOTHER
DISTURBANCE WILL AFFECT THE REGION TUESDAY INTO WEDNESDAY.
&&
.NEAR TERM /UNTIL 6 AM FRIDAY MORNING/...
FROST ADVISORIES ISSUED FOR SOME LOCATIONS AROUND THE I95 CORRIDOR
FOR LATE TONIGHT WHERE THE GROWING SEASON HAS STARTED.
A GFS/WRF-NMMB BLEND SEEMED TO WORK BEST OFF THE 12Z SOUNDINGS AND
MODELING INITIALIZATION. OUR FORECAST IMPACT UNFORTUNATELY IS
COMING FROM NON SOUNDING LOCATIONS AND THUS ADDS A LAYER OF
UNCERTAINTY TO THE NEAR AND SHORT TERM FORECASTS.
THE MOISTURE OFF THE OCEAN, THE RAP HAS HAD A BETTER HANDLE ON IT
THAN THE PLAN FORECAST MOISTURE FIELDS OF THE GFS AND WRF-NMMB.
IT WAS USED AS A BASIS FOR TONIGHT`S FORECAST.
BASED ON THE RAP`S PREMISE WE SEE THAT MIXING IS FINALLY STOPPING
THE WESTWARD PROGRESSION OF THE STRATOCU CIG. BUT, WE EXPECT THIS
PROCESS TO START ITSELF LATER THIS EVENING AND OVERNIGHT AS THE
MOISTURE REMAINS TRAPPED UNDERNEATH THE INVERSION AND IS FORECAST TO
SPREAD. EAST OF THE GFS AND WRF-NMMB RIDGE AXIS LINE IS A PROXY TO
WHERE THE CIGS HAVE BEEN ABLE TO SUSTAIN THEMSELVES. THIS AXIS
SHIFTS WEST TONIGHT AS WE ARE EXPECTING THE CLOUDS TO GO. BASED ON
INCREASING DEW POINTS AND MORE MARGINAL TEMPERATURES WE HAVE OPTED
TO CONVERT THE FREEZE WATCH TO A FROST ADVISORY. HIGHEST CONFIDENCE
IS IN THE WESTERN PART OF THE HEADLINES WITH LOWER CONFIDENCE IN NJ.
WE DID KEEP THE MENTION OF SOME PATCHY FROST (IN THE HWO TOO) IN
LOCALES FARTHER TO THE SE (BUT NOT IN CENTRAL/LOWER DELMARVA). BEING
CONSISTENT WITH THE CLOUD AND WIND IDEA, FOR MIN TEMPS WE ARE HIGHER
THAN STAT GUIDANCE EAST AND CLOSER TO A STAT GUIDANCE BLEND WEST.
&&
.SHORT TERM /6 AM FRIDAY MORNING THROUGH 6 PM FRIDAY/...
THE 925MB LEVEL DRY AIR SOUTH OF MAINE AND EAST OF MASSACHUSETTS IS
DESTINED TO MOVE WESTWARD OVERNIGHT AND BE OVER OUR CWA ON FRIDAY.
ALSO THE SFC HIGH IS FORECAST TO BE NESTLED PRETTY MUCH OVER OUR
CWA. WE ARE EXPECTING THE LOW CLOUD CIG TO DISSIPATE DURING THE
MORNING. THIS IN PART WILL BE REPLACED BY HIGH LEVEL CLOUDINESS
ASSOCIATED WITH THE WEAKENING COLD FRONT APPROACHING FROM THE WEST.
GIVEN THE LATEST RIDGE AXIS POSITION, WE REMOVED THE LOW CHC OF PCPN
NEAR THE COAST. AWAY FROM THE COAST WE LEANED TOWARD THE HIGHER OF
THE STAT GUIDANCE FOR MAX TEMPS AND MORE OF A BLEND CLOSER TO AND
ALONG THE ATLANTIC.
&&
.LONG TERM /FRIDAY NIGHT THROUGH THURSDAY/...
A FAIRLY BENIGN PATTERN FOR OUR REGION DURING THE LONG TERM. A WEAK
UPPER TROUGH WILL MOVE THROUGH THE NORTHEAST AND MIDDLE ATLANTIC
FRIDAY THRU SATURDAY. ANOTHER TROUGH WILL WILL MOVE FROM THE GREAT
LAKES MONDAY NIGHT AND CROSS INTO THE ATLANTIC BY EARLY WEDNESDAY.
THESE TWO SYSTEMS ARE FAIRLY WEAK AND SHOULD ONLY BRING SMALL CHC
FOR SHOWERS TO THE AREA MON NIGHT INTO TUE NIGHT. PREVIOUS FCSTS HAD
SOME SHOWERS IN FOR FRI NIGHT ALSO...BUT WE HAVE REMOVED THEM FROM
THE FCST ATTM...SINCE THE CHC LOOKS LESS WITH THE MEAGER AMTS OF
LIFT AND LIMITED MOISTURE.
TEMPERATURES WILL START OUT COOL FOR FRI WITH HIGHS ONLY IN THE
LOW/MID 50S ACROSS THE AREA. READINGS WILL THEN CLIMB TO NEAR NORMAL
LEVELS FOR SAT THRU MONDAY. TEMPERATURES WILL THEN BE 5 TO 10
DEGREES ABOVE NORMAL NEXT TUESDAY...BEFORE SETTLING BACK TO NEAR
NORMAL NEXT WED. NORMAL TEMPERATURES FOR THIS TIME OF YEAR ARE HIGHS
IN THE MID 60S AND LOWS IN THE MID 40S FOR PHILADELPHIA. UP ACROSS
THE NORTH IN THE POCONOS AN NRN NJ...THE NORMALS ARE CLOSE TO 10
DEGREES LESS THAN THOSE FOR PHILADELPHIA.
&&
.AVIATION /22Z THURSDAY THROUGH TUESDAY/...
THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG, KILG,
KMIV, KACY AND SURROUNDING AREAS.
EAST WINDS WILL AVERAGE AROUND 10 KTS WITH GUSTINESS UP TO AROUND
20 KTS FROM THE KPHL AREA TERMINALS EASTWARD.
REST OF EVENING AND OVERNIGHT, PREDICTING A MVFR CIG TO OVERSPREAD
ALL THE TERMINALS ARRIVING AT KABE AND KRDG AFTER MIDNIGHT. WINDS
SHOULD BECOME LIGHTER FROM THE EAST. MVFR HAS ALREADY REACHED KACY.
ON FRIDAY MORNING, THE MVFR CIG IS EXPECTED TO DISSIPATE WITH A
CIRRUS DECK ABOVE IT. SYNOPTIC SCALE WINDS OVERALL SHOULD BE
LIGHTER (GENERALLY AN EASTWARD COMPONENT) THAN TODAY AND A SEA
BREEZE FRONT MAY FORM DURING THE AFTERNOON.
OUTLOOK...
FRI NIGHT THRU MON NIGHT...MOSTLY VFR.
TUESDAY...MOSTLY VFR WITH SCT SHOWERS.
&&
.MARINE...
NO CHANGES TO THE MARINE HEADLINES. SCA CONDITIONS IN THE LOWER
DELAWARE BAY ARE EXPECTED TO END THIS EVENING. THE WIND PART OF THE
SCA SHOULD ALSO END OVER THE OCEAN TONIGHT. BUT, SEAS WILL TAKE
LONGER TO GET BELOW SCA CRITERIA ON THE OCEAN AS WE ARE EXPECTING
THEM TO LINGER THROUGH THE DAY ON FRIDAY.
OUTLOOK...
FRI NIGHT AND SAT...SEAS ON THE OCEAN WILL REMAIN JUST BELOW SCA
CONDITIONS.
SAT NIGHT THRU SUN NIGHT...SCA CONDITIONS ON THE OCEAN.
MON THRU TUESDAY...MOSTLY SUB-SCA CONDITIONS.
&&
.PHI WATCHES/WARNINGS/ADVISORIES...
PA...FROST ADVISORY FROM 1 AM TO 8 AM EDT FRIDAY FOR PAZ060-101>104-
106.
NJ...FROST ADVISORY FROM 1 AM TO 8 AM EDT FRIDAY FOR NJZ012-015-019.
DE...NONE.
MD...FROST ADVISORY FROM 1 AM TO 8 AM EDT FRIDAY FOR MDZ008.
MARINE...SMALL CRAFT ADVISORY UNTIL 6 PM EDT FRIDAY FOR ANZ450>455.
SMALL CRAFT ADVISORY UNTIL MIDNIGHT EDT TONIGHT FOR ANZ431.
&&
$$
SYNOPSIS...O`HARA
NEAR TERM...GIGI/NIERENBERG
SHORT TERM...GIGI
LONG TERM...O`HARA
AVIATION...GIGI/NIERENBERG/O`HARA
MARINE...GIGI/O`HARA
AREA FORECAST DISCUSSION
NWS MOUNT HOLLY NJ
311 PM EDT THU APR 17 2014
.SYNOPSIS...
A RIDGE OF HIGH PRESSURE WILL REMAIN ACROSS THE FORECAST AREA
TONIGHT THROUGH FRIDAY NIGHT. A COLD FRONT WILL CROSS THE REGION
FRIDAY NIGHT. MORE HIGH PRESSURE WILL BUILD DOWN FROM CANADA AND
REMAIN ACROSS THE AREA THIS WEEKEND AND INTO MONDAY NIGHT. ANOTHER
DISTURBANCE WILL AFFECT THE REGION TUESDAY INTO WEDNESDAY.
&&
.NEAR TERM /UNTIL 6 AM FRIDAY MORNING/...
FROST ADVISORIES ISSUED FOR SOME LOCATIONS AROUND THE I95 CORRIDOR
FOR LATE TONIGHT WHERE THE GROWING SEASON HAS STARTED.
A GFS/WRF-NMMB BLEND SEEMED TO WORK BEST OFF THE 12Z SOUNDINGS AND
MODELING INITIALIZATION. OUR FORECAST IMPACT UNFORTUNATELY IS
COMING FROM NON SOUNDING LOCATIONS AND THUS ADDS A LAYER OF
UNCERTAINTY TO THE NEAR AND SHORT TERM FORECASTS.
THE MOISTURE OFF THE OCEAN, THE RAP HAS HAD A BETTER HANDLE ON IT
THAN THE PLAN FORECAST MOISTURE FIELDS OF THE GFS AND WRF-NMMB.
IT WAS USED AS A BASIS FOR TONIGHT`S FORECAST.
THE SPREADING UNCERTAINTY OF THE CLOUD COVER AND WIND COUPLED WITH
BELOW NORMAL TEMPS DID NOT MAKE THE FROST/FREEZE DECISION AN EASY OR
CONFIDENT ONE. PLEASE CHECK FOR FURTHER UPDATES LATER THIS AFTERNOON
AND EVENING.
BASED ON THE RAP`S PREMISE WE SEE THAT MIXING IS FINALLY STOPPING
THE WESTWARD PROGRESSION OF THE STRATOCU CIG. BUT, WE EXPECT THIS
PROCESS TO START ITSELF LATER THIS EVENING AND OVERNIGHT AS THE
MOISTURE REMAINS TRAPPED UNDERNEATH THE INVERSION AND IS FORECAST TO
SPREAD. EAST OF THE GFS AND WRF-NMMB RIDGE AXIS LINE IS A PROXY TO
WHERE THE CIGS HAVE BEEN ABLE TO SUSTAIN THEMSELVES. THIS AXIS
SHIFTS WEST TONIGHT AS WE ARE EXPECTING THE CLOUDS TO GO. BASED ON
INCREASING DEW POINTS AND MORE MARGINAL TEMPERATURES WE HAVE OPTED
TO CONVERT THE FREEZE WATCH TO A FROST ADVISORY. HIGHEST CONFIDENCE
IS IN THE WESTERN PART OF THE HEADLINES WITH LOWER CONFIDENCE IN NJ.
WE DID KEEP THE MENTION OF SOME PATCHY FROST (IN THE HWO TOO) IN
LOCALES FARTHER TO THE SE (BUT NOT IN CENTRAL/LOWER DELMARVA). BEING
CONSISTENT WITH THE CLOUD AND WIND IDEA, FOR MIN TEMPS WE ARE HIGHER
THAN STAT GUIDANCE EAST AND CLOSER TO A STAT GUIDANCE BLEND WEST.
&&
.SHORT TERM /6 AM FRIDAY MORNING THROUGH 6 PM FRIDAY/...
THE 925MB LEVEL DRY AIR SOUTH OF MAINE AND EAST OF MASSACHUSETTS IS
DESTINED TO MOVE WESTWARD OVERNIGHT AND BE OVER OUR CWA ON FRIDAY.
ALSO THE SFC HIGH IS FORECAST TO BE NESTLED PRETTY MUCH OVER OUR
CWA. WE ARE EXPECTING THE LOW CLOUD CIG TO DISSIPATE DURING THE
MORNING. THIS IN PART WILL BE REPLACED BY HIGH LEVEL CLOUDINESS
ASSOCIATED WITH THE WEAKENING COLD FRONT APPROACHING FROM THE WEST.
GIVEN THE LATEST RIDGE AXIS POSITION, WE REMOVED THE LOW CHC OF PCPN
NEAR THE COAST. AWAY FROM THE COAST WE LEANED TOWARD THE HIGHER OF
THE STAT GUIDANCE FOR MAX TEMPS AND MORE OF A BLEND CLOSER TO AND
ALONG THE ATLANTIC.
&&
.LONG TERM /FRIDAY NIGHT THROUGH THURSDAY/...
A FAIRLY BENIGN PATTERN FOR OUR REGION DURING THE LONG TERM. A WEAK
UPPER TROUGH WILL MOVE THROUGH THE NORTHEAST AND MIDDLE ATLANTIC
FRIDAY THRU SATURDAY. ANOTHER TROUGH WILL WILL MOVE FROM THE GREAT
LAKES MONDAY NIGHT AND CROSS INTO THE ATLANTIC BY EARLY WEDNESDAY.
THESE TWO SYSTEMS ARE FAIRLY WEAK AND SHOULD ONLY BRING SMALL CHC
FOR SHOWERS TO THE AREA MON NIGHT INTO TUE NIGHT. PREVIOUS FCSTS HAD
SOME SHOWERS IN FOR FRI NIGHT ALSO...BUT WE HAVE REMOVED THEM FROM
THE FCST ATTM...SINCE THE CHC LOOKS LESS WITH THE MEAGER AMTS OF
LIFT AND LIMITED MOISTURE.
TEMPERATURES WILL START OUT COOL FOR FRI WITH HIGHS ONLY IN THE
LOW/MID 50S ACROSS THE AREA. READINGS WILL THEN CLIMB TO NEAR NORMAL
LEVELS FOR SAT THRU MONDAY. TEMPERATURES WILL THEN BE 5 TO 10
DEGREES ABOVE NORMAL NEXT TUESDAY...BEFORE SETTLING BACK TO NEAR
NORMAL NEXT WED. NORMAL TEMPERATURES FOR THIS TIME OF YEAR ARE HIGHS
IN THE MID 60S AND LOWS IN THE MID 40S FOR PHILADELPHIA. UP ACROSS
THE NORTH IN THE POCONOS AN NRN NJ...THE NORMALS ARE CLOSE TO 10
DEGREES LESS THAN THOSE FOR PHILADELPHIA.
&&
.AVIATION /19Z THURSDAY THROUGH TUESDAY/...
THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG, KILG,
KMIV, KACY AND SURROUNDING AREAS.
THE 18Z TAFS MVFR CONDITIONS ARE FORECAST TO OCCUR AT ALL OF THE
TAF SITES TONIGHT AND FRIDAY MORNING, ALTHOUGH CONFIDENCE IS
PROGRESSIVELY LOWER THE FARTHER WEST OUR TAF SITES ARE.
FOR THE REST OF THIS AFTERNOON INTO EARLY THIS EVENING A VFR STRATOCU
CIG IS EXPECTED TO CONTINUE TO MOVE WEST AND BE BATTLED BY SOME
MIXING AND DRY AIR. FROM KPHL AREA TERMINALS EASTWARD WE ARE
EXPECTING A VFR CIG AT TIMES, ALTHOUGH KACY MIGHT BECOME MVFR.
FARTHER WEST NO CIG EXPECTED.
EAST WINDS WILL AVERAGE AROUND 10 KTS WITH GUSTINESS UP TO AROUND
20 KTS FROM THE KPHL AREA TERMINALS EASTWARD.
REST OF EVENING AND OVERNIGHT, PREDICTING A MVFR CIG TO OVERSPREAD
ALL THE TERMINALS ARRIVING AT KABE AND KRDG AFTER MIDNIGHT. WINDS
SHOULD BECOME LIGHTER FROM THE EAST.
ON FRIDAY MORNING, THE MVFR CIG IS EXPECTED TO DISSIPATE WITH A
CIRRUS DECK ABOVE IT. SYNOPTIC SCALE WINDS OVERALL SHOULD BE
LIGHTER (GENERALLY AN EASTWARD COMPONENT) THAN TODAY AND A SEA
BREEZE FRONT MAY FORM DURING THE AFTERNOON.
OUTLOOK...
FRI NIGHT THRU MON NIGHT...MOSTLY VFR.
TUESDAY...MOSTLY VFR WITH SCT SHOWERS.
&&
.MARINE...
NO CHANGES TO THE MARINE HEADLINES. SCA CONDITIONS IN THE LOWER
DELAWARE BAY ARE EXPECTED TO END THIS EVENING. THE WIND PART OF THE
SCA SHOULD ALSO END OVER THE OCEAN TONIGHT. BUT, SEAS WILL TAKE
LONGER TO GET BELOW SCA CRITERIA ON THE OCEAN AS WE ARE EXPECTING
THEM TO LINGER THROUGH THE DAY ON FRIDAY.
OUTLOOK...
FRI NIGHT AND SAT...SEAS ON THE OCEAN WILL REMAIN JUST BELOW SCA
CONDITIONS.
SAT NIGHT THRU SUN NIGHT...SCA CONDITIONS ON THE OCEAN.
MON THRU TUESDAY...MOSTLY SUB-SCA CONDITIONS.
&&
.PHI WATCHES/WARNINGS/ADVISORIES...
PA...FROST ADVISORY FROM 1 AM TO 8 AM EDT FRIDAY FOR PAZ060-101>104-
106.
NJ...FROST ADVISORY FROM 1 AM TO 8 AM EDT FRIDAY FOR NJZ012-015-019.
DE...NONE.
MD...FROST ADVISORY FROM 1 AM TO 8 AM EDT FRIDAY FOR MDZ008.
MARINE...SMALL CRAFT ADVISORY UNTIL 6 PM EDT FRIDAY FOR ANZ450>455.
SMALL CRAFT ADVISORY UNTIL MIDNIGHT EDT TONIGHT FOR ANZ431.
&&
$$
SYNOPSIS...O`HARA
NEAR TERM...GIGI
SHORT TERM...GIGI
LONG TERM...O`HARA
AVIATION...GIGI/O`HARA
MARINE...GIGI/O`HARA
AREA FORECAST DISCUSSION
NWS MOUNT HOLLY NJ
100 PM EDT THU APR 17 2014
.SYNOPSIS...
HIGH PRESSURE WILL MOVE OUT OF NEW ENGLAND AND ACROSS THE CANADIAN
MARITIMES BUT STILL EXTEND ACROSS THE EASTERN SEABOARD THROUGH EARLY
FRIDAY. A FRONTAL BOUNDARY WILL MOVE ACROSS THE AREA FRIDAY NIGHT
INTO SATURDAY MORNING, BEFORE HIGH PRESSURE REESTABLISHES ITSELF
ACROSS EASTERN CANADA AND BUILDS SOUTHWARD ALONG THE EASTERN SEABOARD
SUNDAY INTO MONDAY. ANOTHER FRONTAL BOUNDARY IS EXPECTED TO AFFECT
THE AREA NEXT TUESDAY, FOLLOWED BY HIGH PRESSURE FOR THE MIDDLE OF
NEXT WEEK.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
NEXT ESTF UPDATE MAINLY FOR AN UPWARD A SKY COVER ADJUSTMENT EAST. WE
FOUND THAT THE RAP IS HANDLING THE 925MB MOISTURE THE BEST. WRF-
NMMB FCST SOUNDINGS ALSO LOOK BETTER THAN THE SOME OF THE PLAN
VIEW MODEL MASS FIELDS. THEY BOTH SHOW SOME DRYING WITH MIXING
LATER IN THE AFTERNOON BEFORE PREDICTED CLOUDS ROLL IN AT NIGHT.
TEMPS IRONICALLY ARE RUNNING TOO LOW VS PREDICTIONS IN SUNNIER
LOCALES FAR NORTH. OVERALL THOUGH NO BIG ADJUSTMENTS MADE THERE.
12Z SOUNDINGS SUPPORT FORECAST MAX TEMPS FOR TODAY.
OTHERWISE...THIS DAY SHOULD BE LOADED WITH SUNSHINE OVER THE
INTERIOR WITH ONLY THIN CIRRUS AT TIMES.
WINDS WILL BE E-NE GUSTING 15 TO 20 MPH AT TIMES.
THE FCST BASIS WAS A 50 50 BLEND 00Z/17 NCEP MOS GUIDANCE.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 AM FRIDAY/...
TONIGHTS FCST WAS ALSO A 50 50 BLEND OF THE 00Z/17 NCEP MOS GUIDANCE.
THAT IN MIND...THE FCST TEMPS ARE GENERALLY FREEZING OR JUST ABOVE.
COLLABORATING THE UNCERTAINTY REGARDING A FREEZE OR A FROST...HAVE
BLENDED THE EARLY FRIDAY MORNING HEADLINE WITH OUR NEIGHBORS. HERE
IN THE MOUNT HOLLY AREA...THINK ODDS FAVOR SLIGHTLY WARMER TEMPS
TONIGHT THAN WHAT OCCURRED THIS THURSDAY MORNING AND SO A FROST APPEARS
MORE LIKELY FROM MY VIEW IN OUR AREA...RATHER THAN A FREEZE BUT
ITS POSSIBLE THE GUIDANCE IS 2 DEGREES TOO WARM?
OTHERWISE THE ONSHORE WIND WILL BE DIMINISHING AND BECOME LIGHT.
ITS POSSIBLE THAT LOW CLOUDS WILL FORM OR HAVE ALREADY FORMED AND
LOCKED INTO PORTIONS OF THE COAST THIS EVENING AND THEN DEVELOP
NWD AS THE BOUNDARY LAYER COOLS....ESPECIALLY CENTRAL NJ. PATCHY
FOG IS ALSO POSSIBLE LATE TONIGHT BUT NOT CURRENTLY IN THE GRIDS.
&&
.LONG TERM /FRIDAY THROUGH WEDNESDAY/...
THE HIGH PRESSURE THAT HAS BEEN EXTENDING SOUTHWARD ACROSS THE EAST
COAST FROM CANADA WILL BEGIN PULLING OUT OF THE AREA DURING THE DAY
FRIDAY. AS THIS HAPPENS, OUR AREA WILL BE IN BETWEEN TWO FEATURES
LATE FRIDAY INTO FRIDAY NIGHT; ONE BEING AN AREA OF LOW PRESSURE TO
OUR SOUTH OFF THE SOUTHEAST COAST AND THE OTHER AN APPROACHING COLD
FRONT. WITH THE PERSISTENT NORTHEAST FLOW ACROSS THE AREA, WE EXPECT
A FAIR AMOUNT OF CLOUD COVER FRIDAY INTO FRIDAY NIGHT. THIS SHOULD
HELP KEEP TEMPERATURES COOL THROUGH THE DAY FRIDAY, SO WE REMAIN
BELOW NORMAL. THE SYSTEM TO OUR SOUTH IS EXPECTED TO REMAIN FAR
ENOUGH TO OUR SOUTH TO PREVENT WIDESPREAD PRECIPITATION TO AFFECT
THE AREA. HOWEVER, THERE REMAINS A SLIGHT CHANCE SOME LIGHT RAIN
ON THE VERY FAR NORTHERN EDGE COULD EXTEND ACROSS OUR SOUTHEASTERN
AREAS, SO WE WILL KEEP SLIGHT CHANCE POPS ACROSS OUR SOUTHEASTERN
ZONES. SOUNDINGS INDICATE THAT THE VERTICAL MOISTURE IS RATHER
SHALLOW, SO IT MAY BE MORE DRIZZLE, SO WE WILL INCLUDE CHANCE
DRIZZLE WITH THE RAIN IN THE FORECAST LATE FRIDAY INTO FRIDAY
NIGHT. THE AFOREMENTIONED COLD FRONT IS EXPECTED TO MOVE THROUGH
THE AREA OVERNIGHT FRIDAY INTO SATURDAY MORNING. ALL GUIDANCE
INDICATES THE PRECIPITATION DRYING OUT AS IT APPROACHES OUR AREA,
SO WE HAVE REMOVED POPS FOR THE REMAINDER OF THE AREA AS WE NOW
EXPECT A DRY FRONTAL PASSAGE.
WE EXPECT DRY WEATHER TO BUILD IN ACROSS THE AREA SATURDAY BEHIND
THE FRONTAL BOUNDARY AS HIGH PRESSURE BEGINS TO BUILD SOUTHWARD OUT
OF CANADA. THE HIGH SHOULD SUPPRESS THE LOW TO OUR SOUTH BY SATURDAY
SO THAT IT WOULDN`T HAVE AN EFFECT ON OUR AREA ANYMORE. THIS HIGH
WILL REESTABLISH ITSELF ACROSS EASTERN CANADA AND BUILDS SOUTHWARD
ALONG THE EASTERN SEABOARD AGAIN INTO SUNDAY AND MONDAY. THIS WILL
CONTINUE TO PROVIDE DRY WEATHER OVER THE WEEKEND INTO MONDAY OF NEXT
WEEK. WITH RIDGING ALOFT TAKING PLACE, TEMPERATURES WILL RETURN
CLOSER TO NORMAL OVER THE WEEKEND INTO EARLY NEXT WEEK.
ON TUESDAY, A COLD FRONT IS FORECAST TO APPROACH THE AREA FROM THE
WEST. AN AREA OF LOW PRESSURE IS FORECAST TO DEVELOP AND STRENGTHEN
ALONG THE BOUNDARY AS IT MOVES ACROSS THE AREA LATE TUESDAY INTO
TUESDAY NIGHT. TUESDAY INTO TUESDAY NIGHT LOOKS TO BE THE NEXT
CHANCE OF PRECIPITATION ACROSS THE AREA. THEREFORE WE HAVE CHANCE
POPS ACROSS THE AREA DURING THIS TIME PERIOD.
THIS LOW IS EXPECTED TO SLOWLY PULL TO OUR NORTHEAST THROUGH
WEDNESDAY AS HIGH PRESSURE BEGINS TO BUILD SOUTHWARD OUT OF CANADA
ONCE AGAIN. WEDNESDAY IS EXPECTED TO BE DRY, BUT SHOULD BE QUITE
GUSTY WITH THE TIGHTENING PRESSURE GRADIENT.
&&
.AVIATION /18Z THURSDAY THROUGH TUESDAY/...
THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG, KILG,
KMIV, KACY AND SURROUNDING AREAS.
WITH 18Z TAFS MVFR CONDITIONS FORECAST TO OCCUR AT ALL OF THE TAF
SITES TONIGHT AND FRIDAY MORNING, ALTHOUGH CONFIDENCE IS
PROGRESSIVELY LOWER THE FARTHER WEST OUR TAF SITES ARE.
FOR THE REST OF THIS AFTERNOON INTO EARLY THIS EVENING A VFR STRATOCU
CIG IS EXPECTED TO CONTINUE TO MOVE WEST AND BE BATTLED BY SOME
MIXING AND DRY AIR. FROM KPHL AREA TERMINALS EASTWARD WE ARE
EXPECTING A VFR CIG AT TIMES, ALTHOUGH KACY MIGHT BECOME MVFR. FARTHER
WEST NO CIG EXPECTED.
EAST WINDS WILL AVERAGE AROUND 10 KTS WITH GUSTINESS UP TO AROUND
20 KTS FROM THE KPHL AREA TERMINALS EASTWARD.
REST OF EVENING AND OVERNIGHT, PREDICTING A MVFR CIG TO OVERSPREAD
ALL THE TERMINALS ARRIVING AT KABE AND KRDG AFTER MIDNIGHT. WINDS
SHOULD BECOME LIGHTER FROM THE EAST.
ON FRIDAY MORNING, THE MVFR CIG IS EXPECTED TO DISSIPATE WITH A
CIRRUS DECK ABOVE IT. SYNOPTIC SCALE WINDS OVERALL SHOULD BE
LIGHTER (GENERALLY AN EASTWARD COMPONENT) THAN TODAY AND A SEA
BREEZE FRONT MAY FORM DURING THE AFTERNOON.
OUTLOOK...
FRIDAY AFTERNOON-FRIDAY NIGHT...MVFR CIGS POSSIBLE, ESPECIALLY
CLOSER TO THE COAST.
SATURDAY-MONDAY...MOSTLY VFR. GUSTY N-NW WINDS 15-20 KNOTS SATURDAY.
&&
.MARINE...
SCA CONTINUES ATLC WATERS WITH SEAS ALREADY 5 FT AND WINDS/SEAS TO
BUILD A LITTLE TODAY BEFORE SLOWLY SUBSIDING LATER TONIGHT.
ADDED LOWER DE BAY TO THE SCA PER EXPECTED WIND IMPACT AT THE BAY
ENTRANCE.
OUTLOOK...
FRIDAY-FRIDAY NIGHT...SEAS LIKELY TO REMAIN 5 FEET OR GREATER ON THE
OCEAN THROUGH EARLY FRIDAY NIGHT, THEN BEGIN TO SUBSIDE.
SATURDAY...SUB-SMALL CRAFT ADVISORY CRITERIA EXPECTED.
SATURDAY NIGHT-SUNDAY...WINDS AND SEAS INCREASING TO SMALL CRAFT
ADVISORY CRITERIA OVERNIGHT SATURDAY AND CONTINUE INTO SUNDAY,
ESPECIALLY ON OCEAN.
SUNDAY NIGHT-MONDAY...A RETURN TO SUB-SMALL CRAFT ADVISORY CRITERIA
EXPECTED SUNDAY NIGHT.
&&
.PHI WATCHES/WARNINGS/ADVISORIES...
PA...FREEZE WATCH FROM LATE TONIGHT THROUGH FRIDAY MORNING FOR
PAZ060-101>103-106.
NJ...FREEZE WATCH FROM LATE TONIGHT THROUGH FRIDAY MORNING FOR
NJZ012-013-015-017>022-027.
DE...NONE.
MD...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 6 PM EDT FRIDAY FOR ANZ450>455.
SMALL CRAFT ADVISORY UNTIL MIDNIGHT EDT TONIGHT FOR ANZ431.
&&
$$
SYNOPSIS...ROBERTSON
NEAR TERM...DRAG/GIGI
SHORT TERM...DRAG
LONG TERM...ROBERTSON
AVIATION...GIGI/ROBERTSON
MARINE...DRAG/ROBERTSON
AREA FORECAST DISCUSSION
NWS MELBOURNE FL
336 PM EDT THU APR 17 2014
.DISCUSSION...
..WET THROUGH SATURDAY WITH POTENTIAL FOR LOCALLY HEAVY RAINFALL
ESPECIALLY ALONG THE COAST...
...HAZARDOUS BOATING CONDITIONS THROUGH THIS WEEKEND AND INTO EARLY
NEXT WEEK...
CURRENT...HIGH PRESSURE OVER THE MID ATLANTIC STATES NORTHWARD
RIDGES TO THE NORTHEAST GULF OF MEXICO. THE NORTHEAST TO EAST
WINDFLOW AROUND THE SOUTHEAST AREA OF THE HIGH WAS PUSHING MARINE
STRATOCU ASHORE EAST CENTRAL FLORIDA. THE 915MHZ VERTICAL WIND
PROFILERS AT THE SPACE CENTER BEAR THIS OUT WITH EASTERLY 20 TO 25
KNOTS WINDS FROM JUST OFF THE SURFACE TO AROUND 5000 FEET/APPROX
850MB. THE WINDS THEN MAKE AN ABRUPT SHIFT TO THE WEST AT AROUND
6500 FEET AND REMAIN OUT OF THE WEST TO 10000 FEET WHICH IS THE
UPPER LIMIT OF THE 915MHZ RECORDING HEIGHTS. THE FRONTAL BOUNDARY
THAT WAS ANALYZED AS A DIFFUSE WARM FRONTAL BOUNDARY JUST SOUTH OF
LAKE OKEECHOBEE THIS MORNING HAS MOVED TO JUST NORTH OF THE LAKE.
WEATHER RADARS DETECTING SCATTERED SHOWERS AND LIGHTNING STORMS OVER
SOUTH FLORIDA WITH MORE SHOWERS AND STORMS ALONG THE FRONTAL
BOUNDARY AS IT SLOWLY LIFTS NORTH ACROSS THE SOUTHERN PORTIONS OF
EAST CENTRAL FLORIDA.
TONIGHT...MODEL TIME HEIGHT CROSS SECTIONS WERE INDICATING THAT THE
CURRENT CONDITIONS SHOULD CONTINUE OVERNIGHT AS THE FRONTAL BOUNDARY
LIFTS SLOWLY NORTHWARD AS A WARM FRONT ASSOCIATED WITH A DEVELOPING
AREA OF LOW PRESSURE IN THE NORTH CENTRAL GULF OF MEXICO.
PRECIPITABLE WATER VALUES BETWEEN AN INCH AND A HALF AND 1.9 INCHES
AND THE LIFT PROVIDED BY THE SOUTHWEST TO WEST WINDS MOVING OVER THE
LOWER LAYER EASTERLY WINDS SHOULD GIVE US AT LEAST CHANCE...30-50
PERCENT... OF OVERNIGHT RAINS.
FRIDAY...THE NEWLY FORMED WARM FRONT ASSOCIATED WITH THE LOW
PRESSURE SYSTEM IN THE NORTH GULF OF MEXICO LIFTS NORTHWARD AS THE
LOW TRACKS OFF TO THE NORTHEAST CROSSING NORTH FLORIDA AND INTO THE
ATLANTIC EAST OF GEORGIA WITH A TRAILING COLD FRONT CROSSING OVER
FLORIDA OVERNIGHT FRIDAY. THE BRISK SOUTH TO SOUTHWEST WINDFLOW
AHEAD OF THE COLD FRONT WILL MAKE FOR A BREEZY FRIDAY WITH RAIN
CHANCES RANGING FROM AROUND 60 PERCENT SOUTHERN AREAS TO 80 TO 90
PERCENT NORTHERN AREAS. HAVE KEPT THUNDERSTORMS IN THE FRIDAY
FORECAST AS COLDER...-10C TO -12C...MID LEVEL AIR MOVES OVERHEAD
STEEPENING MID LEVEL LAPSE RATES AND STRONG MID LEVEL IMPULSE MOVES
OVERHEAD DURING THE DAY FRIDAY. TEMPERATURES RANGE FROM THE MID 80S
SOUTHERN AREAS TO LOW 80S NORTHWEST VOLUSIA AND NORTHEAST LAKE
COUNTIES.
FRIDAY NIGHT...THE COLD FRONT IS EXPECTED TO SWEEP ACROSS CENTRAL
FLORIDA OVERNIGHT FRIDAY AND SATURDAY MORNING CLEARING CENTRAL
FLORIDA SATURDAY AFTERNOON. LOWS SATURDAY MORNING MID AND UPPER 60S.
SATURDAY-SATURDAY NIGHT...SOUTHWEST TO WEST WINDS ADVECTING GULF
MOISTURE ACROSS THE PENINSULA KEEP RAIN CHANCES IN THE 30 TO 50
PERCENT AREA. HIGHS RANGE SHOULD RANGE FROM THE UPPER 70S NORTHWEST
LAKE COUNTY TO THE MID 80S ON THE IN THE AREAS ON THE LEEWARD SIDE
OF LAKE OKEECHOBEE. NORTHWEST WINDS OVERNIGHT SATURDAY BRING COOLER
AIR INTO CENTRAL FLORIDA. OVERNIGHT SATURDAY/SUNRISE SUNDAY MORNING
LOWS IN THE MID AND UPPER 50S SUNRISE SUNDAY MORNING.
PREVIOUS ZONES DISCUSSION
TODAY-TONIGHT...POST FRONTAL DRY AIRMASS REMAIN FAIRLY PERVASIVE
ACROSS THE REGION...ESPECIALLY ACROSS THE INTERIOR AND VOLUSIA
COUNTY WHERE DEWPOINTS ARE STILL IN THE MID-UPPER 50S.
MODELS HAVE SO FAR BEEN VERY GUNG HO IN LIFTING THE OLD FRONTAL
BOUNDARY/ENHANCED MOISTURE BACK NORTH...BUT IT APPEARS THAT THE
NORTHWARD TREND MAY BE STARTING AS ONE HEAVY RAINBAND SET UP EARLIER
THIS EVENING ACROSS BROWARD COUNTY THAT HAS SINCE DISSIPATED.
CURRENT ANALYSIS SHOWS A BAND OF ENHANCED LOW LEVEL MOISTURE FROM
BREVARD/OSCEOLA COUNTIES SOUTHWARDS COINCIDENT WITH AN AREA OF WIND
CONVERGENCE IN THE 1000-850MB LAYER. THIS IS WHERE RADAR IS ALSO NOW
PICKING UP ON A RECENT UPSWING IN SHOWER COVERAGE.
LOCAL WRF MODEL SHOWS A BAND OF ENHANCED PRECIP AROUND DAYBREAK OVER
THE TREASURE COAST...BUT HRRR MODEL KEEPS THIS ACTIVITY MORE OVER
SOUTH FLORIDA UNTIL LATER. ITS TOUGH TO SAY WHERE OR IF ANY LOCALLY
HEAVY BANDS MAY SET UP UNTIL THEY DO...BUT JUST AHEAD OF/ALONG WARM
FRONT WOULD BE THE BEST BET. DO EXPECT AN INCREASE IN SHOWER
FREQUENCY TOWARDS DAYBREAK ACROSS THE TREASURE COAST.
FRONTAL REMNANTS AND BEST ISENTROPIC LIFT WILL MOVE BACK TO THE
NORTH ACROSS CENTRAL FLORIDA THROUGH THE DAY...ACCELERATING INTO
NORTH FLORIDA TONIGHT AS UPPER LEVEL SHORTWAVE SWINGS EASTWARDS AND
SURFACE LOW DEVELOPS ACROSS THE GULF. HAVE TAPERED BACK RAIN CHANCES
TO 20 PERCENT NORTHERN INTERIOR TO 60 PERCENT OKEECHOBEE/TREASURE
COAST BASED ON CURRENT TRENDS/MODEL FORECAST. COULD SEE A FEW
PERIODS OF HEAVY RAIN ALONG THE COAST TODAY...BEFORE THE BEST RAIN
CHANCES WILL LIFT NORTH OF THE REGION LATER TONIGHT.
THOUGH IT WILL BE BREEZY AGAIN THIS AFTERNOON...IT DOESN`T APPEAR
THAT SPEEDS/GUSTS WILL BE QUITE AS HIGH AS YESTERDAY SO HAVE NOT
ISSUED A LAKE WIND ADVISORY. HOWEVER CONDITIONS WILL STILL REMAIN
CHOPPY ON AREA LAKES.
COASTAL HIGHS WILL BE HIGHLY DEPENDENT ON CLOUD COVER AND PRECIP
TIMING...BUT OVERALL EXPECTED ANYWHERE FROM LOW 70S ALONG VOLUSIA
COAST TO UPPER 70S/AROUND 80 IN BREVARD/TREASURE COAST. INTERIOR
TEMPS IN THE UPPER 70S AND LOW 80S. MILD OVERNIGHT AS FLOW BECOMES
MORE EAST-SOUTHEAST WITH LOWS IN THE UPPER 60S INTERIOR/AROUND 70S
COAST.
FRI-SUN...THE OVERALL TREND OF THE SHORT RANGE FORECAST IS DECIDEDLY
SLOWER AND WETTER INTO SUNDAY. STRONG SOUTHERN STREAM SHORT WAVE
TROUGH WILL MOVE EAST ALONG THE ERN GULF COAST BEFORE PINCHING OFF
INTO A CLOSED MID-UPPER LOW INVOF THE FL/AL/GA TRI-STATE REGION FRI
NIGHT. THE CLOSED LOW WILL THEN DRIFT SLOWLY EAST SOMEWHERE BTWN THE
FL/GA BORDER AND PENINSULAR NORTH FL ON SAT...EASING OFFSHORE SAT
NIGHT AND DRIFTING FARTHER OFFSHORE AND AWAY FROM THE FL EAST COAST
ON SUN.
AT THE SURFACE...AVBL MODEL GUIDANCE HAS CONVERGED TOWARD A MORE
AGREEABLE (SLOWER) SOLUTION...ALTHOUGH THE GFS CONTINUES TO BE THE
FASTEST. SFC FRONTAL WAVE SPINS UP INTO A LOW AND TRACKS ACROSS THE
NERN GOMEX FRI...WITH THE SFC AND MID/UPPER LEVEL LOWS BECOMING
VERTICALLY STACKED BY FRI NIGHT OVER NORTH FL. SFC WARM FRONT LIFTS
NORTHWARD THROUGH CENTRAL FL DURING THE MORNING...WHICH SHOULD TAKE
WIDESPREAD STRATIFORM RAINFALL NWD ACROSS NORTH FL/GA...WHILE ECFL
BREAKS OUT INTO THE WARM SECTOR OF THE GOMEX LOW. DEEP LAYER S-SW
FLOW WITH PWATS AROUND 1.75" WILL LEAD TO WIDESPREAD SHOWERS/STORMS
WITH THE POTENTIAL FOR A BAND OF STRONGER STORMS TO REACH CTRL FL
FROM THE GOMEX (N/W OF I-4) AROUND SUNSET (GIVE OR TAKE) AND
CONTINUE TO DROP SEWD THROUGH THE EVENING HOURS.
SFC LOW WILL BE VERY SLOW TO MOVE ACROSS THE STATE FRI NIGHT...AND
THEN LINGER OFFSHORE THE FL EAST COAST THROUGHOUT SAT. SUFFICIENT
WRAP AROUND MOISTURE WILL EXIST FOR SCT TO NMRS SHOWERS...AND EVEN
SOME STORMS GIVEN THE COLD H50 TEMPS UNDERNEATH THE H50 LOW OVHD.
EXPECT LINGERING SHOWERS SAT NIGHT/SUNDAY IN COOL/MOIST NRLY FLOW
ON BACK SIDE OF THE LOW...WHICH WILL BE GRUDGINGLY SLOW TO PUT SPACE
BETWEEN ITSELF AND FL. COVERAGE/INTENSITY SHOULD BE RATHER LOW.
MON-WED...WEAK HIGH PRESSURE FINALLY SETTLES IN TOWARD FL EARLY NEXT
WEEK...AND DRYING CONDS OUT. THERE ARE SOME SUGGESTIONS OF A WEAK
FRONTAL TROUGH AND ASCD MOISTURE BAND TAKING A GLANCING SHOT AT NORTH
FL TUE-NIGHT INTO WED...BUT WILL NOT GET TOO INVOLVED IN DISSECTING
DAY 6-7 POPS GIVEN THE MORE SIG WX IN DAYS 1-3.
&&
.AVIATION...PREVAILING MVFR THROUGH THE EVENING AND OVERNIGHT AS A
WARM FRONT AND WITH AREAS OF LIGHT TO MODERATE RAIN MOVES SLOWLY UP
THE PENINSULA. PREVAILING VFR OVC FRIDAY AS THE WARM FRONT CLEARS
AND WE ARE IN THE WARM SECTOR.
PREVIOUS AVIATION
MOIST AND CLOUDY THROUGH THE PERIOD...THOUGH OVERALL IT
APPEARS MOST LOCATIONS WILL REMAIN JUST INSIDE VFR WITH PREVAILING
CIGS FL035-050. COASTAL SITES WILL BE MORE LIKELY TO SEE MVFR CIGS
FL020-030. ISOLD SHRA MOVING ONSHORE INTO AREAS SOUTH OF KVRB
THROUGH 13Z...THEN BECOMING SCT-NMRS. COVERAGE WILL INCREASE FROM
SOUTH-NORTH AS OLD FRONTAL BOUNDARY LIFTS BACK TO THE NORTH THROUGH
THE DAY. A FEW HEAVIER SHRA MAY PRODUCE TEMPO IFR CONDITIONS MAINLY
ALONG COASTAL SITES. COULD SEE PREVAILING IFR CIGS LATER TONIGHT AS
WARM FRONT LIFTS NORTH OF REGION.
&&
.MARINE...
CURRENT-OVERNIGHT...NOAA BUOYS 009 AND 010 WERE RECORDING NORTHEAST
WINDS AROUND 20 KNOTS AND 8 TO 9 FOOT SEAS. THE TWO SCRIPPS BUOYS 4
AND 6NM OFF THE COAST WERE RECORDING 4 AND 7 FEET RESPECTIVELY.
NORTHEAST TO EAST WINDS AROUND 20 KNOTS CONTINUE OVERNIGHT AS A SLOW
MOVING WARM FRONT WORKS ITS WAY NORTHWARD. WILL KEEP THE SMALL CRAFT
ADVISORY THROUGH THE EVENING THROUGH 4AM COASTAL ISSUANCE.
FRI...WINDS SHIFT TO SOUTH AND SOUTHWEST AS THE COASTAL WATERS COME
INTO THE WARM SECTOR BETWEEN THE WARM FRONT TO THE NORTH AND THE
COLD FRONT IN THE CENTRAL/EASTERN GULF OF MEXICO. WINDS DECREASE AS
THE PRESSURE GRADIENT IN THE WARM SECTOR DECREASES BUT EXPECT TO
HAVE SMALL CRAFT EXERCISE CAUTION WITH 15-20KT AND SEAS TO 6FT
POSSIBLY A BIT HIGHER.
SAT-MON (MODIFIED)... COVERAGE OF RAIN AND STORMS/GUSTY WINDS WILL
REMAIN MARINE THREATS INTO SATURDAY. SYNOPTIC GRADIENT WINDS WILL
BEGIN TO PICK BACK UP SAT AFTERNOON AS THE LOW CENTER MOVES OFFSHORE
THE FL EAST COAST AND PGRAD TIGHTENS. SEAS WILL RAMP BACK UP TO
7-10FT OR A LITTLE HIGHER SAT NIGHT THROUGH SUN AS W-NW WINDS SHIFT
TO N AND NNE BEHIND THE SLOWLY DEPARTING LOW. SLOW IMPROVEMENT IN
WINDS SEAS MON.
&&
.PRELIMINARY POINT TEMPS/POPS...
DAB 68 78 68 74 / 30 90 60 30
MCO 68 82 67 79 / 30 80 60 30
MLB 72 81 71 79 / 30 60 60 30
VRB 72 81 71 80 / 30 60 60 30
LEE 66 79 65 77 / 30 90 60 30
SFB 67 82 68 79 / 30 80 60 30
ORL 68 82 67 79 / 30 80 60 30
FPR 72 82 70 81 / 30 60 60 30
&&
.MLB WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
AM...SMALL CRAFT ADVISORY UNTIL 6 AM EDT FRIDAY FOR COASTAL WATERS
FROM FLAGLER BEACH TO VOLUSIA BREVARD COUNTY LINE OUT 20 NM-
COASTAL WATERS FROM VOLUSIA BREVARD COUNTY LINE TO
SEBASTIAN INLET OUT 20 NM-WATERS FROM FLAGLER BEACH TO
VOLUSIA BREVARD COUNTY LINE 20 TO 60 NM OFFSHORE-WATERS
FROM VOLUSIA BREVARD COUNTY LINE TO SEBASTIAN INLET 20 TO
60 NM OFFSHORE.
SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS UNTIL 6 AM EDT FRIDAY
FOR COASTAL WATERS FROM SEBASTIAN INLET TO JUPITER INLET
OUT 20 NM-WATERS FROM SEBASTIAN INLET TO JUPITER INLET 20
TO 60 NM OFFSHORE.
&&
$$
FORECASTS...WIMMER
IMPACT WX...VOLKMER
AREA FORECAST DISCUSSION
NWS MIAMI FL
303 PM EDT THU APR 17 2014
.NEAR TERM...(THIS EVENING)
THE INITIAL CONCERN WILL BE THROUGH LATE AFTERNOON AND EVENING
PERIODS ALONG THE GULF COAST AND FROM NAPLES TO THE LAKE REGION DUE
TO THE POTENTIAL FOR STRONG THUNDERSTORMS AND HEAVY RAINFALL
ASSOCIATED WITH A FRONTAL BOUNDARY LIFTING NORTH. THE LATEST RADAR
LOOP SHOWED SCATTERED TO NUMEROUS SHOWERS AND A FEW EMBEDDED
THUNDERSTORMS SHIFTING WESTWARD TOWARD THE GULF COAST ACROSS THE
INTERIOR AREAS. THE LATEST HRRR AND WRF MODELS REFLECT THIS AND
INDICATE THIS ACTIVITY BECOMING CONCENTRATED AROUND THE NAPLES AREA
THROUGH THIS TIME. IF THIS SCENARIO UNFOLDS...LOCALIZED FLOODING
COULD BECOME AN ISSUE DEPENDING ON WHERE THE HEAVY RAINFALL FOCUSES.
IN ADDITION TO THE RAINFALL...A FEW STRONG STORMS CAN`T BE RULED OUT
THROUGH THIS TIME OVER THESE AREAS WITH THE MAIN THREATS BEING
STRONG WIND GUSTS AND HAIL. THE MORNING SOUNDING INDICATED DECENT
MID-LEVEL LAPSE RATES WITH -12 C DEG 500 MB TEMPERATURES ALONG WITH
1.8" PWS. 85/AG
.SHORT TERM...(TONIGHT THROUGH SATURDAY)...
THE LATEST SHORT-RANGE MODEL GUIDANCE REMAINS IN DECENT AGREEMENT
AND GENERALLY INDICATES THE WARM FRONT LIFTING NORTH OUT OF OUR
LOCAL AREA TONIGHT AS A COLD FRONT ASSOCIATED WITH A GULF LOW
APPROACHES THE AREA FROM THE WEST FRIDAY AND FRIDAY NIGHT. THE
FRONTAL BOUNDARY IS PROGGED TO MOVE THROUGH THE AREA WITH DRIER AIR
AND NW FLOW SATURDAY AFTERNOON THROUGH SATURDAY NIGHT. MODEL
SOUNDINGS INDICATE THE LOW-LEVEL FLOW SHIFTING TO THE SOUTH THROUGH
THE DAY FRIDAY WITH DECENT DRY MID-LEVEL AIR FILLING IN FROM THE
SOUTHEAST. ALTHOUGH SOME SHOWER/TSTM ACTIVITY WILL REMAIN POSSIBLE
THROUGH THE DAY FRIDAY...ESPECIALLY AROUND THE LAKE THROUGH THE
AFTERNOON PERIOD...PLENTY OF UPPER CLOUDS MAY ACT TO LIMIT
INSTABILITY DURING THE PEAK HEATING HOURS OF THE DAY...WHICH IS
INDICATED FROM THE MODEL SOUNDINGS. THE LATEST WRF MODEL
REFLECTIVITIES MAINLY SHOW SCATTERED ACTIVITY DEVELOPING ALONG AND
JUST AHEAD OF THE FRONTAL BOUNDARY LATE FRIDAY NIGHT THROUGH EARLY
SATURDAY MORNING AS THE FRONT APPROACHES AND BEGINS TO MOVE INTO
THE AREA. TEMPERATURES WILL REMAIN AT AND JUST ABOVE NORMAL
THROUGH THIS TIME...THEN TREND BACK TO NORMAL IN THE WAKE OF THE
FRONTAL BOUNDARY SATURDAY NIGHT INTO SUNDAY MORNING. 85/AG
.LONG TERM...(SUNDAY-EARLY NEXT WEEK)
THE DRY WEATHER WILL REMAIN IN PLACE OVER SOUTH FLORIDA FOR EARLY
NEXT WEEK...AS HIGH PRESSURE BUILDS INTO THE SOUTHEASTERN UNITED
STATES FROM THE CENTRAL UNITED STATES. THE HIGH WILL THEN MOVE EAST
INTO THE WESTERN ATLANTIC WATERS FOR THE MIDDLE TO END OF NEXT WEEK
ALLOWING FOR A COLD FRONT TO MOVE THROUGH SOUTH FLORIDA. THIS FRONT
WILL BE A DRY COLD FRONT WHICH WILL JUST REINFORCE THE DRY WEATHER
OVER SOUTH FLORIDA FOR THE MIDDLE TO END OF NEXT WEEK.
BNB
&&
.MARINE...
LIGHT TO MODERATE NORTHEAST WINDS WILL SHIFT TO THE SOUTHEAST BY
FRIDAY AS A WARM FRONT LIFTS NORTH AND A COLD FRONT APPROACHES AND
MOVES THROUGH THE AREA FRIDAY NIGHT INTO SATURDAY MORNING. A MIX OF
NORTHEAST SWELL AND WIND WAVES WILL REMAIN AT ADVISORY LEVELS
THROUGH TONIGHT...THEN ONCE AGAIN OVER THE WEEKEND IN THE WAKE OF
THE COLD FRONT...MAINLY ACROSS THE PALM BEACH WATERS. IN ADDITION TO
THE WINDS AND SEAS...SCATTERED TO NUMEROUS SHOWERS AND ISOLATED
STORMS OVER THE LOCAL WATERS WILL BE CAPABLE OF GENERATING FREQUENT
LIGHTNING...HEAVY RAINFALL AND LOCALLY CHOPPIER CONDITIONS IN AND
AROUND THE HEAVIER SHOWERS.
&&
.PRELIMINARY POINT TEMPS/POPS...
WEST PALM BEACH 73 84 72 86 / 40 50 50 40
FORT LAUDERDALE 74 85 75 87 / 30 40 50 40
MIAMI 73 85 74 86 / 30 40 50 40
NAPLES 70 87 69 79 / 40 50 50 30
&&
.MFL WATCHES/WARNINGS/ADVISORIES...
FL...HIGH RIP CURRENT RISK UNTIL 8 PM EDT THIS EVENING FOR FLZ168.
AM...SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS UNTIL 2 AM EDT FRIDAY
FOR AMZ650-670.
GM...NONE.
&&
$$
SHORT TERM...84/AK
LONG TERM....85/AG
AREA FORECAST DISCUSSION
NWS GOODLAND KS
108 PM MDT THU APR 17 2014
.UPDATE...
ISSUED AT 702 AM MDT THU APR 17 2014
PLACED FOG IN FOR THIS MORNING OVER THE NORTHWEST PART OF THE
AREA...MAINLY YUMA COUNTY. FOG SHOULD LIFT IN THE NEXT 2 HOURS OR SO.
&&
.SHORT TERM...(TODAY THROUGH SATURDAY NIGHT)
ISSUED AT 421 AM MDT THU APR 17 2014
FORECAST PROBLEMS WILL BE WINDS THROUGH THE PERIOD AND CHANCE OF
PRECIPITATION LATE IN THE PERIOD. SATELLITE SHOWING A SOMEWHAT
AMPLIFIED BUT STILL PROGRESSIVE FLOW FROM THE PACIFIC THROUGH NORTH
AMERICA. STRONG SYSTEM SYSTEM APPROACHING THE PACIFIC NORTHWEST AND
SOUTHWEST CANADA WITH A RIDGE PUSHING IN AHEAD OF IT. AT THIS TIME
THIS IS LEAVING A NORTHWEST FLOW WITH EMBEDDED SHORTWAVE TROUGHS
OVER THE AREA.
AT JET LEVEL...THE NAM WAS DOING A LITTLE BETTER THAN THE GFS. AT MID
LEVELS...OVERALL THE MODELS WERE NOT TOO FAR APART WOULD HAVE TO
GIVE A SLIGHT EDGE TO THE GFS. HOWEVER WITH THE SYSTEM CURRENTLY
PASSING THROUGH THE REGION...THE ECMWF WAS DOING THE BEST. THE
CANADIAN WAS DOING A LITTLE BETTER THAN THE ECMWF...GFS AND NAM ON
THE SURFACE WIND/PRESSURE FIELD. THE GFS WAS DOING A LITTLE BETTER
THAN THE OTHER OUTPUT IN THE LOW LEVEL THERMAL FIELD.
TODAY/TONIGHT...LEFT FRONT QUADRANT STARTS OUT NEAR THE WESTERN END
OF THE AREA AT THE BEGINNING OF THE DAY AND THEN WILL MOVE ACROSS
THE EASTERN HALF DURING THE AFTERNOON...WHICH MEANS IT WILL BE EAST
OF THE AREA AT THE BEGINNING OF THE NIGHT. UPPER SYSTEM WILL
CONTINUE TO AFFECT THE FAR SOUTHERN PORTION OF THE AREA EARLY THIS
MORNING. BASED ON CURRENT RADAR/OBSERVATIONAL TRENDS...SLIGHT
CHANCE TO LOW CHANCE OF PRECIPITATION IN THE FAR SOUTH LOOKS
REASONABLE AND DID NOT ADJUST.
NEXT BUT MINOR CONCERN WILL BE HOW LONG THE CLOUD COVER WILL LAST
THIS MORNING AND IF THAT WILL AFFECT THE HIGH TEMPERATURES. MODELS
NOT DOING A GOOD JOB WITH THE STRATUS WITH RAP DOING THE BEST AND
WILL CONTINUE TO WATCH IT AND OBSERVATIONAL TRENDS TO MAKE ANY
FURTHER ADJUSTMENTS. AS SYSTEM TO OUR SOUTH PULLS OUT...SHOULD GET
A DECENT AMOUNT OF SUBSIDENCE FROM THAT BUT AS MENTIONED ABOVE THE
UPPER JET IS NOT YET TO OUR EAST. DUE TO THE LINGERING CLOUD COVER
AND UNFAVORABLE SURFACE WINDS...ESPECIALLY IN THE EASTERN PORTION...
WILL NOT GET TOO EXCITED ABOUT WARMING TEMPERATURES AND STUCK CLOSE
TO THE PREVIOUS FORECAST.
IF SKY COVER CLEARS AS THE MODELS THINK AND THE GRADIENT
TIGHTENS/PRESSURE FALLS OCCUR AS SURFACE HIGH MOVES EAST AND THE
LEE TROUGH DEVELOPS...WINDS SHOULD GET AT LEAST BREEZY IN THE
WESTERN HALF MAYBE EVEN WINDY. NO HIGHLIGHT WILL BE NEEDED. WINDS
WILL STAY UP TONIGHT AS WARM AIR ADVECTION KICKS IN. MINS WILL BE
WARMER AND MAY NEED TO BE WARMED UP MORE FROM WHAT I HAVE THEM.
FRIDAY/FRIDAY NIGHT...RIDGING ALOFT MOVES IN/THROUGH IN THE FIRST
HALF OF THE DAY WITH FLOW ALOFT TRANSITIONING TO SOUTHWEST IN THE
AFTERNOON. WARMER 850 MB TEMPERATURES AND PLENTY OF SUN WILL ALLOW
FOR A GOOD WARMUP. TENDED TO FOLLOW THE WARMER GUIDANCE.
HOWEVER...THE BIGGER STORY WILL BE THE INCREASING WINDS. GRADIENT
AND 3 HOUR PRESSURE FALLS ARE TIGHTER/LARGER THAN FOR TODAY SO WILL
DEFINITELY SEE A WINDY DAY. SOME OF THE GUIDANCE WOULD SAY WIND
SPEEDS WILL GET NEAR WIND ADVISORY CRITERIA. THIS WILL BE POSSIBLE
DUE TO THE SOUTHWEST FLOW ALOFT DEVELOPING AHEAD OF OUR NEXT STORM
SYSTEM THAT IS MOVING INTO THE DESERT SOUTHWEST. DAY SHIFT WILL
NEED TO LOOK AT THIS CLOSELY AGAIN TO NOT ONLY INCREASE SPEEDS BUT
ALSO AT A POSSIBLE WIND ADVISORY.
LACK OF INSTABILITY AND AN EXTREMELY DEEP DRY LAYER IN THE LOWER
LEVELS OF THE ATMOSPHERE WILL KEEP PRECIPITATION FROM DEVELOPING OR
REACHING THE GROUND DURING THE NIGHT. NO UPPER JET IS CLOSE AND NO
LOW LEVEL JET LOOKS TO BE IN THE AREA. SO REMOVED THE SLIGHT CHANCE
OF PRECIPITATION FROM THE NIGHTTIME PERIOD. WITH WARM AIR AND SOME
MOISTURE ADVECTION STRATUS AND MAYBE SOME FOG MAY DEVELOP/MOVE INTO
THE AREA. SINCE ONLY THE NAM IS SHOWING IT AND THE 06Z NAM PULLED
BACK FROM EARLIER SOLUTION...WILL NOT INCLUDE ANY FOG BUT THE DAY
SHIFT WILL NEED TO TAKE ANOTHER LOOK.
SATURDAY/SATURDAY NIGHT...SPLIT FLOW WILL BE OVER THE AREA THROUGH
THIS PERIOD. THIS IS LEADING TO MAJOR DIFFERENCES IN HOW THE
MODELS HANDLE THE POSITION OF FEATURES AT ALL LEVELS ACROSS THE
AREA. OVERALL THE DETERMINISTIC MODEL CONSENSUS AND ENSEMBLES WERE
SIDING MORE WITH A SLOWER ARRIVING AND FURTHER SOUTHWEST UPPER
TROUGH MOVING IN AND THROUGH THE AREA DURING THIS PERIOD. HOW THE
DETERMINISTIC OUTPUT HANDLED THE MID/UPPER LEVELS AFFECTED HOW
FAST THEY MOVED IN THE FRONT WITH A SIMILAR CONSENSUS AS WHAT WAS
SHOWN FOR THE UPPER LEVELS. THE 06Z NAM SLOWED DOWN FROM THE 00Z
RUN AND MORE CLOSELY RESEMBLED THE ECMWF AND CANADIAN WHICH LOOKED TO
BE HANDLING THE BEHAVIOR OF THE LEE SIDE TROUGH BETTER THAN
EVERYBODY ELSE.
SO DUE TO THE MODEL TRENDS AND ENSEMBLES...SIDED WITH THE SLOWER
AND FURTHER SOUTHWEST UPPER SOLUTION. SO THIS MEANT I PREFERRED
THE SLOWER/FURTHER WEST FRONTAL POSITION FOR THE DAY. SO AHEAD OF
THE FRONT...MOSTLY IN THE SOUTHEAST PORTION...BREEZY TO WINDY
CONDITIONS WILL ONCE AGAIN OCCUR. MORE IMPORTANTLY THE FRONTAL
POSITION WILL DETERMINE WHERE THE BEST CHANCE OF PRECIPITATION WILL
BE. IN ADDITION TO THAT...THE MODELS...DESPITE THE FRONT...TENDED
TO CAP THE LOW LEVELS WITH THE NORTHWEST HALF HAVING THE LEAST AMOUNT
OF CAP. SO BASED ON THE CAP...AND A FURTHER WEST FRONTAL POSITION...
I REDUCED THE CHANCE OF PRECIPITATION AND PUT THE HIGHEST POPS IN
THE NORTHWEST AND CENTRAL POSITION WHERE THE BOUNDARY/BEST LOW LEVEL
CONVERGENCE IS AND WHERE THE CAP IS WEAKEST. ALSO CLOUD COVER IN
ADVANCE OF THIS SYSTEM COULD INHIBIT HEATING AND EXPECTED
INSTABILITY.
TEMPERATURES WILL BE TRICKY DUE TO THE UNCERTAINTY OF THE FRONTAL
POSITION AND ALSO THE AMOUNT OF CLOUD COVER IN ADVANCE OF THE UPPER
STORM SYSTEM. MODELS TENDED TO BE WARMER...ESPECIALLY AHEAD OF THE
FRONT. HOWEVER...DID NOT GO AS WARM AS I COULD DUE TO THE CLOUD
COVER.
BEST TIME FOR PRECIPITATION LOOKS TO ARRIVE DURING THE NIGHT. THE
DEEPEST LIFT ARRIVES DURING THAT TIME AND THE DETERMINISTIC QPF
OUTPUT AND ENSEMBLE PRECIPITATION PROBABILITIES AGREE WITH THAT.
THE SOUTHEAST HALF LOOKS TO HAVE THE BEST CHANCE. SO LEFT THE
PRECIPITATION FORECAST FOR THE NIGHT ALONE. SOMETHING TO WATCH FOR
ONCE THUNDERSTORMS DEVELOP. STORM MOVEMENTS WILL BE SLOW AND NEARLY
PARALLEL TO THE FRONT. SO THERE WILL BE POTENTIAL FOR TRAINING AND
HEAVY RAINFALL.
.LONG TERM...(FRIDAY NIGHT THROUGH THURSDAY)
ISSUED AT 1252 PM MDT THU APR 17 2014
SOUTHERN STREAM SHORTWAVE TROUGH WILL APPROACH THE AREA
SATURDAY AFTERNOON. COLD FRONT FORECAST TO BE NEAR A NORTON TO
TRIBUNE LINE WILL BE THE MOST LIKELY AREA FOR CONVECTIVE
INITIATION. SBCAPE AXIS OF UP TO 1500 J/KG WILL BE IN PLACE ALONG
AND EAST OF THE FRONT WITH AFTERNOON TEMPERATURES WELL INTO THE
80S. DEEP LAYER SHEAR OF 20-30KTS IS FORECAST FOR THAT AREA. THOSE
PARAMETERS ONLY MARGINALLY SUPPORTIVE OF SEVERE STORMS BUT STILL
COULD SEE SOME SMALL HAIL POSSIBLY UP TO QUARTER SIZE WITH
STRONGER UPDRAFTS. MORE SHOWERS/ISOLATED THUNDERSTORMS WILL
DEVELOP IN THE POST FRONTAL UPSLOPE ENVIRONMENT SATURDAY NIGHT AS
MAIN SYNOPTIC SCALE FORCING ARRIVES. MODELS SHOW SCATTERED SHOWERS
AND ISOLATED THUNDER LINGERING INTO SUNDAY WITH COLDER AIR ALOFT
ASSOCIATED WITH THE UPPER SHORTWAVE...BUT INSTABILITY WILL BE
VERY LIMITED BY THAT TIME SO NOTHING SEVERE. HIGH TEMPERATURES ON
SUNDAY WILL BE AROUND 70.
UPPER RIDGE WILL REBUILD FOR EARLY NEXT WEEK. WARMING SURFACE
TEMPERATURES AND UPSLOPE FLOW INTO COLORADO WILL CONTRIBUTE TO
ISOLATED AFTERNOON/EARLY EVENING STORMS DESPITE LACK OF UPPER
LEVEL FORCING. ACTIVITY WILL BE DIURNAL IN NATURE...QUICKLY
DISSIPATING AFTER SUNSET. NEXT SHORTWAVE TROUGH WILL ARRIVE ON
WEDNESDAY BUT MODELS INDICATE MOST OF THE LOCAL AREA WILL GET DRY
SLOTTED. HOWEVER...DRY LINE WILL BE NEAR THE FAR EASTERN COUNTIES
AND THEY STAND THE BEST CHANCES OF GETTING THUNDERSTORMS WEDNESDAY
AFTERNOON AND WEDNESDAY NIGHT. UPPER TROUGH AXIS WILL STILL BE
NEARBY ON THURSDAY SO HARD TO RULE OUT AN ISOLATED SHOWER OR
THUNDERSTORM THOUGH INSTABILITY AXIS WILL BE FAR EAST BY THAT
TIME. TEMPERATURES MONDAY THROUGH WEDNESDAY WILL BE ABOVE TO MUCH
ABOVE NORMAL THEN NEAR NORMAL ON THURSDAY.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z FRIDAY AFTERNOON)
ISSUED AT 1125 AM MDT THU APR 17 2014
MORNING STRATUS IS RAPIDLY BURNING OFF. STRATUS HAS CLEARED KMCK
AND SHOULD CLEAR KGLD WITHIN THE NEXT 1-2 HOURS. SOUTH WINDS INCREASE
THIS AFTERNOON AND REMAIN ELEVATED THROUGHOUT THE TAF CYCLE...
ESPECIALLY AT KGLD. FORECAST GUIDANCE INDICATES ANOTHER ROUND OF
STRATUS IS POSSIBLE TOMORROW MORNING AS MOISTURE RETURN INCREASES.
FOR NOW...HAVE PLACED A SCT MVFR GROUP IN TAF FOR KGLD AND FEW
MVFR GROUP FOR KMCK. THE MAJORITY OF THE STRATUS SHOULD STAY
SOUTH. SOUTH WINDS BECOME GUSTY DURING THE LATE MORNING TOMORROW
AS A LEE TROUGH STRENGTHENS ALONG THE FRONT RANGE.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
UPDATE...JTL
SHORT TERM...BULLER
LONG TERM...024
AVIATION...RRH
AREA FORECAST DISCUSSION
NWS GOODLAND KS
1125 AM MDT THU APR 17 2014
.UPDATE...
ISSUED AT 702 AM MDT THU APR 17 2014
PLACED FOG IN FOR THIS MORNING OVER THE NORTHWEST PART OF THE
AREA...MAINLY YUMA COUNTY. FOG SHOULD LIFT IN THE NEXT 2 HOURS OR SO.
&&
.SHORT TERM...(TODAY THROUGH SATURDAY NIGHT)
ISSUED AT 421 AM MDT THU APR 17 2014
FORECAST PROBLEMS WILL BE WINDS THROUGH THE PERIOD AND CHANCE OF
PRECIPITATION LATE IN THE PERIOD. SATELLITE SHOWING A SOMEWHAT
AMPLIFIED BUT STILL PROGRESSIVE FLOW FROM THE PACIFIC THROUGH NORTH
AMERICA. STRONG SYSTEM SYSTEM APPROACHING THE PACIFIC NORTHWEST AND
SOUTHWEST CANADA WITH A RIDGE PUSHING IN AHEAD OF IT. AT THIS TIME
THIS IS LEAVING A NORTHWEST FLOW WITH EMBEDDED SHORTWAVE TROUGHS
OVER THE AREA.
AT JET LEVEL...THE NAM WAS DOING A LITTLE BETTER THAN THE GFS. AT MID
LEVELS...OVERALL THE MODELS WERE NOT TOO FAR APART WOULD HAVE TO
GIVE A SLIGHT EDGE TO THE GFS. HOWEVER WITH THE SYSTEM CURRENTLY
PASSING THROUGH THE REGION...THE ECMWF WAS DOING THE BEST. THE
CANADIAN WAS DOING A LITTLE BETTER THAN THE ECMWF...GFS AND NAM ON
THE SURFACE WIND/PRESSURE FIELD. THE GFS WAS DOING A LITTLE BETTER
THAN THE OTHER OUTPUT IN THE LOW LEVEL THERMAL FIELD.
TODAY/TONIGHT...LEFT FRONT QUADRANT STARTS OUT NEAR THE WESTERN END
OF THE AREA AT THE BEGINNING OF THE DAY AND THEN WILL MOVE ACROSS
THE EASTERN HALF DURING THE AFTERNOON...WHICH MEANS IT WILL BE EAST
OF THE AREA AT THE BEGINNING OF THE NIGHT. UPPER SYSTEM WILL
CONTINUE TO AFFECT THE FAR SOUTHERN PORTION OF THE AREA EARLY THIS
MORNING. BASED ON CURRENT RADAR/OBSERVATIONAL TRENDS...SLIGHT
CHANCE TO LOW CHANCE OF PRECIPITATION IN THE FAR SOUTH LOOKS
REASONABLE AND DID NOT ADJUST.
NEXT BUT MINOR CONCERN WILL BE HOW LONG THE CLOUD COVER WILL LAST
THIS MORNING AND IF THAT WILL AFFECT THE HIGH TEMPERATURES. MODELS
NOT DOING A GOOD JOB WITH THE STRATUS WITH RAP DOING THE BEST AND
WILL CONTINUE TO WATCH IT AND OBSERVATIONAL TRENDS TO MAKE ANY
FURTHER ADJUSTMENTS. AS SYSTEM TO OUR SOUTH PULLS OUT...SHOULD GET
A DECENT AMOUNT OF SUBSIDENCE FROM THAT BUT AS MENTIONED ABOVE THE
UPPER JET IS NOT YET TO OUR EAST. DUE TO THE LINGERING CLOUD COVER
AND UNFAVORABLE SURFACE WINDS...ESPECIALLY IN THE EASTERN PORTION...
WILL NOT GET TOO EXCITED ABOUT WARMING TEMPERATURES AND STUCK CLOSE
TO THE PREVIOUS FORECAST.
IF SKY COVER CLEARS AS THE MODELS THINK AND THE GRADIENT
TIGHTENS/PRESSURE FALLS OCCUR AS SURFACE HIGH MOVES EAST AND THE
LEE TROUGH DEVELOPS...WINDS SHOULD GET AT LEAST BREEZY IN THE
WESTERN HALF MAYBE EVEN WINDY. NO HIGHLIGHT WILL BE NEEDED. WINDS
WILL STAY UP TONIGHT AS WARM AIR ADVECTION KICKS IN. MINS WILL BE
WARMER AND MAY NEED TO BE WARMED UP MORE FROM WHAT I HAVE THEM.
FRIDAY/FRIDAY NIGHT...RIDGING ALOFT MOVES IN/THROUGH IN THE FIRST
HALF OF THE DAY WITH FLOW ALOFT TRANSITIONING TO SOUTHWEST IN THE
AFTERNOON. WARMER 850 MB TEMPERATURES AND PLENTY OF SUN WILL ALLOW
FOR A GOOD WARMUP. TENDED TO FOLLOW THE WARMER GUIDANCE.
HOWEVER...THE BIGGER STORY WILL BE THE INCREASING WINDS. GRADIENT
AND 3 HOUR PRESSURE FALLS ARE TIGHTER/LARGER THAN FOR TODAY SO WILL
DEFINITELY SEE A WINDY DAY. SOME OF THE GUIDANCE WOULD SAY WIND
SPEEDS WILL GET NEAR WIND ADVISORY CRITERIA. THIS WILL BE POSSIBLE
DUE TO THE SOUTHWEST FLOW ALOFT DEVELOPING AHEAD OF OUR NEXT STORM
SYSTEM THAT IS MOVING INTO THE DESERT SOUTHWEST. DAY SHIFT WILL
NEED TO LOOK AT THIS CLOSELY AGAIN TO NOT ONLY INCREASE SPEEDS BUT
ALSO AT A POSSIBLE WIND ADVISORY.
LACK OF INSTABILITY AND AN EXTREMELY DEEP DRY LAYER IN THE LOWER
LEVELS OF THE ATMOSPHERE WILL KEEP PRECIPITATION FROM DEVELOPING OR
REACHING THE GROUND DURING THE NIGHT. NO UPPER JET IS CLOSE AND NO
LOW LEVEL JET LOOKS TO BE IN THE AREA. SO REMOVED THE SLIGHT CHANCE
OF PRECIPITATION FROM THE NIGHTTIME PERIOD. WITH WARM AIR AND SOME
MOISTURE ADVECTION STRATUS AND MAYBE SOME FOG MAY DEVELOP/MOVE INTO
THE AREA. SINCE ONLY THE NAM IS SHOWING IT AND THE 06Z NAM PULLED
BACK FROM EARLIER SOLUTION...WILL NOT INCLUDE ANY FOG BUT THE DAY
SHIFT WILL NEED TO TAKE ANOTHER LOOK.
SATURDAY/SATURDAY NIGHT...SPLIT FLOW WILL BE OVER THE AREA THROUGH
THIS PERIOD. THIS IS LEADING TO MAJOR DIFFERENCES IN HOW THE
MODELS HANDLE THE POSITION OF FEATURES AT ALL LEVELS ACROSS THE
AREA. OVERALL THE DETERMINISTIC MODEL CONSENSUS AND ENSEMBLES WERE
SIDING MORE WITH A SLOWER ARRIVING AND FURTHER SOUTHWEST UPPER
TROUGH MOVING IN AND THROUGH THE AREA DURING THIS PERIOD. HOW THE
DETERMINISTIC OUTPUT HANDLED THE MID/UPPER LEVELS AFFECTED HOW
FAST THEY MOVED IN THE FRONT WITH A SIMILAR CONSENSUS AS WHAT WAS
SHOWN FOR THE UPPER LEVELS. THE 06Z NAM SLOWED DOWN FROM THE 00Z
RUN AND MORE CLOSELY RESEMBLED THE ECMWF AND CANADIAN WHICH LOOKED TO
BE HANDLING THE BEHAVIOR OF THE LEE SIDE TROUGH BETTER THAN
EVERYBODY ELSE.
SO DUE TO THE MODEL TRENDS AND ENSEMBLES...SIDED WITH THE SLOWER
AND FURTHER SOUTHWEST UPPER SOLUTION. SO THIS MEANT I PREFERRED
THE SLOWER/FURTHER WEST FRONTAL POSITION FOR THE DAY. SO AHEAD OF
THE FRONT...MOSTLY IN THE SOUTHEAST PORTION...BREEZY TO WINDY
CONDITIONS WILL ONCE AGAIN OCCUR. MORE IMPORTANTLY THE FRONTAL
POSITION WILL DETERMINE WHERE THE BEST CHANCE OF PRECIPITATION WILL
BE. IN ADDITION TO THAT...THE MODELS...DESPITE THE FRONT...TENDED
TO CAP THE LOW LEVELS WITH THE NORTHWEST HALF HAVING THE LEAST AMOUNT
OF CAP. SO BASED ON THE CAP...AND A FURTHER WEST FRONTAL POSITION...
I REDUCED THE CHANCE OF PRECIPITATION AND PUT THE HIGHEST POPS IN
THE NORTHWEST AND CENTRAL POSITION WHERE THE BOUNDARY/BEST LOW LEVEL
CONVERGENCE IS AND WHERE THE CAP IS WEAKEST. ALSO CLOUD COVER IN
ADVANCE OF THIS SYSTEM COULD INHIBIT HEATING AND EXPECTED
INSTABILITY.
TEMPERATURES WILL BE TRICKY DUE TO THE UNCERTAINTY OF THE FRONTAL
POSITION AND ALSO THE AMOUNT OF CLOUD COVER IN ADVANCE OF THE UPPER
STORM SYSTEM. MODELS TENDED TO BE WARMER...ESPECIALLY AHEAD OF THE
FRONT. HOWEVER...DID NOT GO AS WARM AS I COULD DUE TO THE CLOUD
COVER.
BEST TIME FOR PRECIPITATION LOOKS TO ARRIVE DURING THE NIGHT. THE
DEEPEST LIFT ARRIVES DURING THAT TIME AND THE DETERMINISTIC QPF
OUTPUT AND ENSEMBLE PRECIPITATION PROBABILITIES AGREE WITH THAT.
THE SOUTHEAST HALF LOOKS TO HAVE THE BEST CHANCE. SO LEFT THE
PRECIPITATION FORECAST FOR THE NIGHT ALONE. SOMETHING TO WATCH FOR
ONCE THUNDERSTORMS DEVELOP. STORM MOVEMENTS WILL BE SLOW AND NEARLY
PARALLEL TO THE FRONT. SO THERE WILL BE POTENTIAL FOR TRAINING AND
HEAVY RAINFALL.
.LONG TERM...(SUNDAY THROUGH WEDNESDAY)
ISSUED AT 421 AM MDT THU APR 17 2014
SUNDAY THE UPPER LEVEL TROUGH WHICH TRIGGERED CONVECTION SATURDAY
WILL MOVE ACROSS THE AREA WITH THE DRY LINE REMAINING NEAR THE KS/CO
BORDER. AS THE TROUGH MOVES THROUGH...STORMS WILL TURN FROM MOVING
NORTHEAST TO MOVING SOUTH...WHICH WILL INCREASE STORM COVERAGE TO
THE SOUTH OF THE AREA IN THE AFTERNOON. SUNDAY EVENING THE UPPER
LEVEL TROUGH WILL BE EAST OF THE AREA CAUSING RAINFALL TO COME TO AN
END.
MONDAY THE UPPER LEVEL RIDGE WILL MOVE IN BEHIND THE EXITING TROUGH.
WITH A DRY ENVIRONMENT IN PLACE AND NO SHORT WAVE TROUGH MOVING
THROUGH SO WILL KEEP THE DAY DRY.
TUESDAY THE RIDGE WILL STILL BE OVER THE AREA. DURING THE AFTERNOON
A WEAK SHORT WAVE TROUGH WILL MOVE OVER THE AREA. DESPITE THE DRY
LINE STILL REMAINING NEAR THE KS/CO LINE...THE WELL ABOVE NORMAL
TEMPERATURES WILL CAUSE LCLS TO BE VERY HIGH WITH LARGE DEW POINT
DEPRESSIONS AT THE LCL AS WELL. DEW POINT DEPRESSIONS SHRINK BY
LATE AFTERNOON BUT THE SHORT WAVE TROUGH WILL FILL BY THEN. MODEL
CONSENSUS HAS NO RAINFALL FORECAST FOR THE AFTERNOON AS THE TROUGH
MOVES THROUGH. BASED ON THE ABOVE CONSIDERATIONS WILL LEAVE THE
FORECAST DRY...BUT WOULD NOT BE SURPRISED TO SEE AN ISOLATED STORM
OR TWO DEVELOP DURING THE LATTER HALF OF THE AFTERNOON BEFORE THE
SHORT WAVE TROUGH FILLS.
WEDNESDAY A SUBTLE UPPER LEVEL SHORT WAVE TROUGH WILL MOVE ACROSS
THE AREA AS THE DRY LINE IS PUSHED EAST ACROSS THE AREA. THE
ENVIRONMENT WILL BE EVEN DRIER THAN TUESDAY SO A THE DRY FORECAST
WILL CONTINUE FOR THE DAY DESPITE THE DRY LINE MOVING ACROSS THE
AREA.
TUESDAY AND WEDNESDAY A TIGHT SURFACE PRESSURE GRADIENT WILL DEVELOP
AS A SURFACE TROUGH MOVES THROUGH THE AREA LEADING TO WINDY
CONDITIONS. DUE LOW RELATIVE HUMIDITIES MOVING IN BEHIND THE DRY
LINE...HAZARDOUS FIRE WEATHER CONDITIONS MAY DEVELOP OVER PARTS OF
EAST CENTRAL COLORADO TUESDAY AND EXTEND EAST INTO FAR NORTHWEST
KANSAS ON WEDNESDAY.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z FRIDAY AFTERNOON)
ISSUED AT 1125 AM MDT THU APR 17 2014
MORNING STRATUS IS RAPIDLY BURNING OFF. STRATUS HAS CLEARED KMCK
AND SHOULD CLEAR KGLD WITHIN THE NEXT 1-2 HOURS. SOUTH WINDS INCREASE
THIS AFTERNOON AND REMAIN ELEVATED THROUGHOUT THE TAF CYCLE...
ESPECIALLY AT KGLD. FORECAST GUIDANCE INDICATES ANOTHER ROUND OF
STRATUS IS POSSIBLE TOMORROW MORNING AS MOISTURE RETURN INCREASES.
FOR NOW...HAVE PLACED A SCT MVFR GROUP IN TAF FOR KGLD AND FEW
MVFR GROUP FOR KMCK. THE MAJORITY OF THE STRATUS SHOULD STAY
SOUTH. SOUTH WINDS BECOME GUSTY DURING THE LATE MORNING TOMORROW
AS A LEE TROUGH STRENGTHENS ALONG THE FRONT RANGE.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
UPDATE...JTL
SHORT TERM...BULLER
LONG TERM...JTL
AVIATION...RRH
AREA FORECAST DISCUSSION
NWS BISMARCK ND
420 PM CDT THU APR 17 2014
.SHORT TERM...(THIS EVENING THROUGH FRIDAY)
ISSUED AT 420 PM CDT THU APR 17 2014
FORECAST HIGHLIGHTS IN THE SHORT TERM PERIOD INCLUDE INCREASING
PRECIPITATION CHANCES ACROSS THE WEST...ESPECIALLY FRIDAY AFTERNOON.
IN THE NEAR TERM...SNOW SHOWERS IN THE FAR SOUTHWEST HAVE
DISSIPATED WHILE CLOUDS CONTINUE TO INCREASE FROM WEST TO EAST
ACROSS THE FORECAST AREA. THE HIGH PRESSURE RIDGE HAS MOVED INTO
THE RED RIVER VALLEY WITH AN INCREASING PRESSURE GRADIENT AND
BRISK SE FLOW ACROSS THE WEST. HIGH RESOLUTION MODELS...INCLUDING
THE RAP AND HRRR..INDICATING A 500MB SHEARED VORTICITY AXIS
PUSHING INTO WESTERN NORTH DAKOTA THIS EVENING AND PUSHING EAST
OVERNIGHT. A SWATH OF ENHANCED LIFT MAY SUPPORT SOME LIGHT
RAIN/SNOW SHOWERS FROM NORTHWEST TO SOUTHEAST TONIGHT AND HAVE
MADE SOME MINOR ADJUSTMENTS TO POPS.
ON FRIDAY...EXPECT BREEZY CONDITIONS BUT WIDESPREAD ADVISORY
CRITERIA (SUSTAINED 30 MPH) IS NOT EXPECTED TO BE REACHED.
INCREASING WARM AIR ADVECTION WILL BOOST AFTERNOON TEMPERATURES
INTO THE 50S TO LOWER 60S. AN UPPER LEVEL LOW WILL PUSH INTO
MONTANA WITH DIFFLUENT SOUTHWEST FLOW SUPPORTING RAIN ACROSS
NORTHWEST NORTH DAKOTA...ESPECIALLY DURING THE AFTERNOON HOURS.
SOME ISOLATED THUNDERSTORMS CAN`T BE RULED OUT WITH A SHOWALTER
INDEX NEAR OR JUST BELOW ZERO.
.LONG TERM...(FRIDAY NIGHT THROUGH THURSDAY)
ISSUED AT 420 PM CDT THU APR 17 2014
THE HIGHLIGHT OF THE EXTENDED FORECAST IS A TRANSITION TO A MORE
ACTIVE WEATHER PATTERN INTO NEXT WEEK.
THE 12 UTC DETERMINISTIC SUITE IS IN GOOD AGREEMENT ON A
PROGRESSIVE SHORTWAVE TO IMPACT THE NORTHERN PLAINS FRIDAY EVENING
INTO SATURDAY MORNING. PRECIPITATION ASSOCIATED WITH ISENTROPIC
LIFT IS EXPECTED TO BEGIN AS RAIN...AND POSSIBLY TRANSITIONING TO
SNOW LATE FRIDAY NIGHT INTO EARLY SATURDAY MORNING. LITTLE TO NO
ACCUMULATION IS ANTICIPATED AT THIS TIME. THEREAFTER...A
SIGNIFICANT TROUGH PROPAGATES INTO THE WESTERN CONUS TUESDAY INTO
THURSDAY...POTENTIALLY PLACING THE NORTHERN PLAINS UNDER SOUTHWEST
FLOW ALOFT. WHILE DIFFERENCES EXIST AMONGST THE GUIDANCE REGARDING
THE EVOLUTION OF THE SYSTEM AS IT PROPAGATES ONTO THE
PLAINS...INCREASING MOISTURE TRANSPORT AND INSTABILITY SUPPORTS
THE POTENTIAL FOR THUNDERSTORMS TUESDAY INTO WEDNESDAY. THE
GUIDANCE BEGINS TO DIVERGE THE MOST THURSDAY...WITH THE 12 UTC
GFS CLOSING OFF A POTENT LOW ACROSS NORTH DAKOTA...WITH THE 12 UTC
ECMWF ACROSS SOUTHERN SASKATCHEWAN. WHILE SIGNIFICANT QPF IS
EXPECTED SOMEWHERE IN THE NORTHERN PLAINS AND CANADIAN
PRAIRIES...PREICPITATION TYPE AND PLACEMENT WILL REMAIN HIGHLY
UNCERTAIN FOR THE COMING DAYS. IN LIGHT OF MOIST
SOILS...HYDROLOGIC IMPACTS WILL ALSO NEED TO BE CONSIDERED.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z FRIDAY AFTERNOON)
ISSUED AT 420 PM CDT THU APR 17 2014
EXPECTING MAINLY LOW VFR CEILINGS BECOMING MVFR THIS EVENING AT
KMOT/KISN/KBIS. ISOLATED LIGHT SNOW SHOWERS WILL BE POSSIBLE
OVERNIGHT AT KISN/KMOT...BUT LOW PROBABILITY DOES NOT WARRANT MORE
THAN A VCSH MENTION AT THIS TIME.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM/AVIATION...RP KINNEY
LONG TERM...AYD
AREA FORECAST DISCUSSION
NWS BISMARCK ND
205 PM CDT THU APR 17 2014
.UPDATE...
ISSUED AT 1252 PM CDT THU APR 17 2014
FORECAST HIGHLIGHTS IN THE SHORT TERM PERIOD INCLUDE INCREASING
PRECIPITATION CHANCES ACROSS THE WEST...ESPECIALLY FRIDAY AFTERNOON.
IN THE NEAR TERM...SNOW SHOWERS IN THE FAR SOUTHWEST HAVE
DISSIPATED WHILE CLOUDS CONTINUE TO INCREASE FROM WEST TO EAST
ACROSS THE FORECAST AREA. THE HIGH PRESSURE RIDGE HAS MOVED INTO
THE RED RIVER VALLEY WITH AN INCREASING PRESSURE GRADIENT AND
BRISK SE FLOW ACROSS THE WEST. HIGH RESOLUTION MODELS...INCLUDING
THE RAP AND HRRR..INDICATING A 500MB SHEARED VORTICITY AXIS
PUSHING INTO WESTERN NORTH DAKOTA THIS EVENING AND PUSHING EAST
OVERNIGHT. A SWATH OF ENHANCED LIFT MAY SUPPORT SOME LIGHT
RAIN/SNOW SHOWERS FROM NORTHWEST TO SOUTHEAST TONIGHT AND HAVE
MADE SOME MINOR ADJUSTMENTS TO POPS.
ON FRIDAY...EXPECT BREEZY CONDITIONS BUT WIDESPREAD ADVISORY
CRITERIA (SUSTAINED 30 MPH) IS NOT EXPECTED TO BE REACHED.
INCREASING WARM AIR ADVECTION WILL BOOST AFTERNOON TEMPERATURES
INTO THE 50S TO LOWER 60S. AN UPPER LEVEL LOW WILL PUSH INTO
MONTANA WITH DIFFLUENT SOUTHWEST FLOW SUPPORTING RAIN ACROSS
NORTHWEST NORTH DAKOTA...ESPECIALLY DURING THE AFTERNOON HOURS.
UPDATE ISSUED AT 951 AM CDT THU APR 17 2014
MORNING UPDATE FOR MINOR CHANGES TO POPS ACROSS THE WEST AND
HOURLY TEMPERATURE TRENDS. LIGHT SNOW SHOWERS CONTINUE ACROSS THE
FAR SOUTHWEST THIS MORNING. EXPECTING TRANSITION TO LIGHT RAIN
THIS AFTERNOON...WITH ANY PRECIPITATION CONFINED MAINLY TO THE
WESTERN THIRD OF THE FORECAST AREA.
UPDATE ISSUED AT 700 AM CDT THU APR 17 2014
BOWMAN RADAR WAS SHOWING WEAK RETURNS THROUGH SOUTHWEST NORTH
DAKOTA. FLURRIES THIS MORNING...ISOLATED RAIN SHOWERS LATER AS WE
WARM...WESTERN THIRD.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 430 AM CDT THU APR 17 2014
FORECAST HIGHLIGHTS IN THE SHORT TERM PERIOD INCLUDE TEMPERATURES
AND POSSIBLY SOME LIGHT SHOWERS IN THE WEST.
CURRENTLY...HIGH PRESSURE WAS CENTERED OVER SOUTHERN MANITOBA WITH
LOW PRESSURE IN THE LEE OF THE ROCKIES. PERSISTENT CLOUDS LINGERED
BETWEEN THE HIGH PRESSURE RIDGE AXIS THAT EXTENDED SOUTHWARD FROM
MANITOBA ACROSS THE CENTRAL DAKOTAS...AND THE LEE-SIDE LOW PRESSURE
TROUGH. REGIONAL RADARS INDICATED THAT LIGHT SHOWERS OR VIRGA
CONTINUED OVER EASTERN MONTANA INTO WESTERN SOUTH DAKOTA AND THE
SOUTHWESTERN CORNER OF NORTH DAKOTA.
THE AREA OF LIGHT SHOWERS IS LIKELY ASSOCIATED WITH AN UPPER LEVEL
IMPULSE MOVING EAST/SOUTHEAST IN THE NORTHWEST FLOW ALOFT. THIS
IMPULSE IS FORECAST TO MOVE ACROSS WESTERN NORTH DAKOTA THIS
MORNING...THEN WEAKEN FURTHER AS IT MOVES INTO EASTERN NORTH DAKOTA
THIS AFTERNOON. MEANWHILE AT THE SURFACE...THE SURFACE GRADIENT
TIGHTENS TODAY AND SHOULD BE CONDUCIVE FOR GUSTY SOUTHEAST WINDS
OVER WESTERN NORTH DAKOTA LATE THIS MORNING AND INTO THE AFTERNOON.
H850 WINDS AROUND 25 MPH FROM THE SOUTHEAST...WITH GOOD WARM
ADVECTION AT H700 WITH WESTERLY WINDS. THIS SCENARIO WILL KEEP WARM
ADVECTION CLOUDS DEVELOPING OVER THE WESTERN HALF OF THE STATE. THIS
COMBINED WITH WEAK UPPER LEVEL ENERGY IMPULSES WILL KEEP A CHANCE OF
SHOWERS OVER WESTERN NORTH DAKOTA TODAY.
TONIGHT A SHORTWAVE RIDGE WILL MOVE INTO WESTERN NORTH DAKOTA AHEAD
OF A MORE SIGNIFICANT TROUGH. THE LEADING EDGE OF UPPER LEVEL ENERGY
WITH THIS NEXT UPPER TROUGH WILL APPROACH NORTHWESTERN NORTH DAKOTA
LATE TONIGHT. THE BEST THUS WILL KEEP A MENTION OF SHOWERS AFTER
MIDNIGHT IN THE NORTHWEST AND NORTH CENTRAL.
THE SLOW WARMING TREND BEGINS WITH HIGHS TODAY IN THE 40S...WITH
LOWER 50S IN THE FAR SOUTHWEST.
.LONG TERM...(FRIDAY THROUGH WEDNESDAY)
ISSUED AT 430 AM CDT THU APR 17 2014
THIS LONG TERM DISCUSSION VERY SIMILAR TO THAT FROM YESTERDAY AND
EXPECTATIONS HAVE CHANGED ONLY SLIGHTLY FOR THE LONG TERM.
OF MOST INTEREST CONTINUES TO BE THE SIGNIFICANT WARM UP JUST IN
TIME FOR EASTER...WITH HIGHS 65 TO 70 FOR MOST OF THE FORECAST
AREA THAT DAY. THE THUNDERSTORM CHANCES REMAIN...ESPECIALLY SOUTH...
FROM LATER TUESDAY THROUGH WEDNESDAY...BUT INSTABILITY PARAMETERS
ARE WEAKER THAN PREVIOUSLY INDICATED.
THE LONG TERM IS VERY ACTIVE WITH A MID LEVEL COLD POCKET PASSING
JUST NORTH OF THE FORECAST AREA TO START...FOLLOWED BY
SIGNIFICANT RIDGING IN THE MID LEVELS BEGINNING SATURDAY AFTERNOON
AND CONTINUING INTO MID WEEK. THE COLD POCKET BRINGS MIXED
PRECIPITATION...PREDOMINANTLY RAIN DURING THE DAY TIMES AND SNOW
AT NIGHT. SNOW ACCUMULATIONS WILL BE MINIMAL WITH MAYBE AN INCH...
AT MOST...WEST AND NORTH. THIS WOULD BE QUICK TO MELT DURING DAY
TIMES AND WITH RAIN.
THE PERIOD IMMEDIATELY AFTER THE LONG TERM...SO THURSDAY AND
FRIDAY...LOOKS WET AT FIRST AND THEN WITH COLDER AIR WORKING IN AS
THE SYSTEM PULLS OUT...A CHANCE THAT PRECIPITATION WOULD END AS A
PERIOD OF SNOW...THAT FOR APRIL 24-25...AND FOR MOST WOULD BE
UNWELCOME.
TO BACK UP A BIT CONCERNING THE THUNDERSTORM CHANCES FOR TUESDAY
AND WEDNESDAY...LOW PRESSURE FORMS IN THE LEE OF THE ROCKIES. THE
THERMAL RIDGE AHEAD OF IT...INTO NORTH DAKOTA...IS NOW DEPICTED BY
THE MODELS NOT AS STRONG AS YESTERDAYS RUNS. THE LOW IS ALSO
DEPICTED WEAKER AND WITH THAT THE INCREASE IN LOW LEVEL MOISTURE
AND INSTABILITY LESS. CAPE THAT WAS FORECAST TO NEAR 1500 J/KG
ALONG THE SOUTH DAKOTA BORDER AND LI TO -4...IS NOW DEPICTED AS
LESS THAN 500 J/KG AND LI TO -2. IT IS STILL PRUDENT TO KEEP A
MENTION OF THUNDERSTORMS...BUT THEY COULD BE MORE THUNDERSHOWERS
AS COMPARED TO STORMS.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z FRIDAY AFTERNOON)
ISSUED AT 1252 PM CDT THU APR 17 2014
EXPECTING MAINLY LOW VFR CEILINGS BECOMING MVFR THIS EVENING AT
KMOT/KISN/KBIS. ISOLATED LIGHT SNOW SHOWERS WILL BE POSSIBLE
OVERNIGHT AT KISN/KMOT...BUT LOW PROBABILITY DOES NOT WARRANT MORE
THAN A VCSH MENTION AT THIS TIME.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE/AVIATION...RP KINNEY
SHORT TERM...JV
LONG TERM...JPM
AREA FORECAST DISCUSSION
NWS WILMINGTON OH
146 PM EDT THU APR 17 2014
.SYNOPSIS...
WARMER TEMPERATURES WILL RETURN TODAY AS SOUTHERLY FLOW DEVELOPS AROUND
HIGH PRESSURE TO OUR NORTHEAST. A WEAK COLD FRONT WILL CROSS OUR REGION
ON FRIDAY...BRINGING A LOW END CHANCE FOR SHOWERS TO THE AREA. HIGH
PRESSURE WILL BRING FAIR WEATHER AND SEASONABLY WARM TEMPERATURES
TO THE REGION THIS WEEKEND.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
THE LATEST RAP MODEL...COMPARED TO THE 12Z KILN SOUNDING...SEEMS
TO BE HANDLING THE OVERALL MOISTURE PROFILE ACROSS THE REGION THIS
MORNING. ALSO...IT IS MIXING THE AIRMASS THROUGH 850 MB BY LATE
AFTN. THIS DEEPER MIXING...ALONG WITH MOSTLY SUNNY SKIES...WILL
YIELD TEMPERATURES A LITTLE WARMER THAN PREVIOUSLY FORECAST. HIGHS
SHOULD RANGE FROM THE MID 60S NORTH TO AROUND 70 NEAR AND SOUTH OF
THE OHIO RIVER.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH FRIDAY NIGHT/...
WEAK LOW PRESSURE WILL CROSS THE NORTHERN GREAT LAKES TONIGHT. A
COLD FRONT EXTENDING SOUTHWARD FROM THIS LOW WILL APPROACH OUR
AREA OVERNIGHT...AND WILL BE LOCATED ACROSS NORTHERN IN/IL BY
DAYBREAK FRIDAY. THE HIGH ACROSS NEW ENGLAND TODAY WILL HAVE MOVED
OFFSHORE BY TONIGHT. THIS WILL RESULT IN A WEAKENING SURFACE
GRADIENT AND LIGHT WINDS OVERNIGHT. THE AIRMASS THAT WILL BE IN
PLACE WILL BE DRY...WITH SURFACE DEWPOINTS EXPECTED TO BE IN THE
30S. SKIES WILL START OFF MOSTLY CLEAR...WITH A GRADUALLY INCREASE
IN CLOUDS FROM WEST TO EAST OVERNIGHT AHEAD OF THE WEAK COLD
FRONT. THE COMBINATION OF DRY AIR AT THE SURFACE...LIGHT
WINDS...AND MOSTLY CLEAR SKIES TO START OFF TONIGHT WILL RESULT IN
TEMPERATURES DROPPING INTO THE 40S. SOME LOCATIONS EAST OF
COLUMBUS MAY DROP INTO THE 30S WITH A LONGER PERIOD OF MOSTLY
CLEAR SKIES EXPECTED THERE.
THE WEAK FRONT WILL ARRIVE IN OUR AREA FROM THE NORTHWEST ON
FRIDAY. MODELS CONTINUE TO TREND TOWARD WEAKENING THIS MOISTURE
STARVED FRONT AS IT MOVES INTO OUR AREA. SHOWERS ARE FORECAST TO
DEVELOP ALONG THE FRONT FRIDAY JUST WEST OF OUR AREA.
HOWEVER...THESE SHOWERS ARE FORECAST TO LESSEN IN COVERAGE AND
WEAKEN AS THEY TRY TO PUSH ACROSS THE AREA FRIDAY AFTERNOON.
ALSO...IT NOW APPEARS THAT THE FRONT WILL BE LOSING ITS
CHARACTERISTICS FRIDAY AFTERNOON AS THE ASSOCIATED LOW LIFTS
NORTHEASTWARD FROM OUR REGION....AND THE CANADIAN HIGH BEHIND THE
LOW FAILS TO BUILD TOO FAR SOUTH INTO THE OHIO VALLEY. ALL OF
THESE FACTORS DO NOT BODE WELL FOR ANY DECENT POPS...AND THE CHANCE
POPS ACROSS OUR NORTHERN ZONES MAY BE GENEROUS FOR THIS FRONT.
HIGHS ON FRIDAY AHEAD OF THE FRONT WILL RISE ONCE AGAIN INTO THE
60S ACROSS ALL ZONES. THE ONLY DIFFERENCE IN TEMPERATURES FRIDAY
COMPARED TO TODAY MAY BE THE SLIGHTLY COOLER LOWER 60S EXPECTED
ACROSS THE NORTH DUE TO THE PROXIMITY OF THE WEAK COLD FRONT.
500-1000 HPA HEIGHTS WILL BEGIN TO BUILD ACROSS THE REGION ON
SATURDAY. HIGH PRESSURE OFF TO THE NORTH WILL PROVIDE
NORTHEASTERLY SURFACE WINDS. THE COUNTERACTING NATURE OF THE
HEIGHT RISES AND NORTHEASTERLY WINDS WILL PRODUCE YET ANOTHER DAY
OF MID TO UPPER 60S ACROSS THE SOUTH ON SATURDAY. ACROSS THE
NORTH...THE NORTHEASTERLY WINDS SHOULD KEEP TEMPERATURES FROM
RISING MUCH ABOVE 60 AS COOLER AIR IS DRAWN ACROSS THOSE ZONES
FROM LAKE ERIE.
SOUTHERLY SURFACE FLOW WILL DEVELOP ON SUNDAY AS THE HIGH TO OUR
NORTH SHIFTS TO OUR NORTHEAST. THE COMBINATION OF THE RETURN FLOW
AND BUILDING 500-1000 HPA HEIGHTS WILL RESULT IN HIGHS IN THE 70S
ACROSS MOST OF THE AREA...WITH PERHAPS A FEW UPPER 60S ACROSS THE
NORTH.
&&
.LONG TERM /SATURDAY THROUGH THURSDAY/...
HIGH PRESSURE STRETCHING FROM SOUTHEAST CANADA THROUGH THE GREAT
LAKES AND OHIO VALLEY WILL KEEP DRY WEATHER OVER THE AREA SATURDAY
AND SUNDAY. A COLD FRONT WILL ENTER THE REGION MONDAY. GFS AND
ECMWF BOTH INDICATE THE FRONT...BUT DIFFERENCES IN TIMING
EXIST...WITH GFS FASTER AND ECMWF OFFERING A SLOWER SOLUTION.
SPLIT THE DIFFERENCE BETWEEN MODELS AND WENT WITH A MODEL
BLEND...WHICH YIELDS THE LIKELIHOOD FOR SHOWERS MONDAY AND MONDAY
NIGHT. WITH MODELS SHOWING SCANT INSTABILITY AND RATHER WEAK WIND
FIELDS ALONG THE FRONT...DECIDED TO OMIT THUNDER. HIGH PRESSURE
AND DRY AIR ARE EXPECTED TO RETURN FOR TUESDAY AND WEDNESDAY.
TEMPERATURES WILL START OUT A BIT COOL ON SATURDAY WITH HIGHS
FORECAST TO BE IN THE UPPER 50S TO MID 60S. DUE TO A MODEST AMOUNT
OF WARM ADVECTION...HIGHS FOR SUNDAY THROUGH WEDNESDAY ARE
ANTICIPATED TO AVERAGE IN THE NEAR NORMAL MID AND UPPER 60S.
&&
.AVIATION /18Z THURSDAY THROUGH TUESDAY/...
LOW PRESSURE OVER EASTERN WISCONSIN WILL MOVE NORTHEAST INTO
SOUTHEAST CANADA THROUGH THE TAF PERIOD. AS IT DOES...A WEAK COLD
FRONT WILL PUSH EAST INTO OUR REGION ON FRIDAY. THIS FRONT IS
MOISTURE STARVED. AS SUCH...NOT MUCH IS EXPECTED IN TERMS OF
PRECIPITATION AS IT CROSSES THE TAF SITES FRIDAY AFTERNOON. HIGH
CLOUDS WILL INCREASE THROUGH THIS EVENING WITH VFR 5000 FOOT
CEILINGS EXPECTED LATE TONIGHT INTO FRIDAY.
OUTLOOK...MVFR CEILINGS AND VISIBILITIES POSSIBLE MONDAY INTO
TUESDAY.
&&
.ILN WATCHES/WARNINGS/ADVISORIES...
OH...NONE.
KY...NONE.
IN...NONE.
&&
$$
SYNOPSIS...HICKMAN/LATTO
NEAR TERM...HICKMAN/LATTO
SHORT TERM...LATTO
LONG TERM...CONIGLIO
AVIATION...HICKMAN