Forecast Discussions mentioning any of
"HRRR" "RAP" "RR" "RUC13" "RUC" received at GSD on 09/13/14
AREA FORECAST DISCUSSION
NWS PHOENIX AZ
335 PM MST THU SEP 11 2014
.UPDATE...UPDATED FIRE WEATHER DISCUSSION.
&&
.SYNOPSIS...
THE COMBINATION OF A RATHER DRY AIRMASS AND HIGH PRESSURE ALOFT IS
EXPECTED TO KEEP SKIES MAINLY CLEAR OVER THE REGION THROUGH FRIDAY.
A VERY SLOW INCREASE IN MOISTURE WILL BEGIN LATE FRIDAY...THEN
CONTINUE INTO THE WEEKEND...AND INTO NEXT WEEK AS THE FLOW ALOFT
BECOMES MORE SOUTHEASTERLY. THIS WILL LEAD TO INCREASED CHANCES OF
SHOWERS AND THUNDERSTORMS...INITIALLY OVER MOUNTAINOUS AREAS OVER
THE WEEKEND...BUT POSSIBLY SPREADING INTO LOWER DESERT LOCATIONS BY
EARLY NEXT WEEK.
&&
.DISCUSSION...
LATEST RAP STREAMLINE ANALYSIS SHOWS A WEAK UPPER LEVEL TROUGH
SITUATED ACROSS AZ. SOMEWHAT DEEPER MOISTURE IS EVIDENT ON WV
IMAGERY EAST OF THE TROUGH ACROSS SOUTHERN AND EASTERN AZ...THOUGH
REGIONAL SOUNDINGS INDICATE PWATS ARE ONLY IN THE 1.0-1.2 INCH
RANGE.
ISOLATED CU HAS DEVELOPED ACROSS A FEW RIDGETOPS THIS
AFTERNOON...THOUGH A LACK OF CAPE IS LIMITING VERTICAL DEVELOPMENT.
CONSENSUS OF CONVECTIVE ALLOWING MODELS SUGGESTS THAT ISOLATED
SHOWER AND THUNDERSTORM ACTIVITY WILL REMAIN CONFINED TO SOUTHERN
AND EASTERN AZ THIS AFTERNOON.
CONTINUED WARMING AND DRYING TREND EXPECTED FRIDAY AS THE
SUBTROPICAL RIDGE REMAINS THE PREDOMINANT WEATHER FEATURE.
AGAIN...LITTLE CHANCE FOR CONVECTION EXCEPT FOR ISOLATED ACTIVITY IN
THE VICINITY OF THE DEEPEST MOISTURE ACROSS SOUTHEASTERN AZ.
&&
.PREVIOUS DISCUSSION...
SATURDAY AND SUNDAY...
A SLOW INCREASE IN THE AVAILABLE MOISTURE LEVELS IS STILL EXPECTED
TO OCCUR OVER THE UPCOMING WEEKEND AS THE FLOW BELOW 400MB BECOMES
EASTERLY TO SOUTHEASTERLY...AND BEGINS TO PULL MOISTURE BACK INTO
THE REGION. THE GFS IS MOST BULLISH ON THIS MOISTURE
INCREASE...PUSHING PWATS UP TO NEAR 1.50 ON SATURDAY...WHILE THE
EURO KEEPS THEM MAINLY AOB 1.20 INCH. CONSIDERING THAT THE PRIMARY
REASON FOR THE INCREASE IN THE SFC PRESSURE GRADIENT/EASTERLY FLOW
IN THE LOW LEVELS IS THE FACT THAT A RATHER STRONG...AND QUITE COLD
SFC HIGH IS FORECAST TO DIVE SOUTHWARD INTO THE CENTRAL AND SOUTHERN
PLAINS...WITH ITS ORIGINS BEING FROM NORTHERN CANADA/ALASKA...RATHER
THAN A MORE TYPICAL SUBTROPICAL HIGH THAT OFTEN BUILDS OVER THAT
REGION THIS TIME OF YEAR...I AM INCLINED TO GO WITH THE DRIER EURO
FOR NOW. STILL...THERE SHOULD BE ENOUGH MOISTURE/INSTABILITY TO KEEP
SLIGHT CHANCES FOR SHOWERS/THUNDERSTORMS OVER THE HIGHER TERRAIN
NORTH AND EAST OF PHOENIX IN THE FORECAST...BUT WITH MAINLY SINGLE
DIGIT POPS OVER THE LOWER DESERTS. HIGH TEMPERATURES ARE EXPECTED TO
REMAIN MOSTLY IN THE 105-108F RANGE ACROSS SE CA AND SW AZ...BUT
COOL A DEGREE OR TWO OVER SOUTH-CENTRAL AZ AS A BIT OF COOLER AIR
WORKS ITS WAY IN FROM THE EAST.
MONDAY THROUGH WEDNESDAY...
A FURTHER MOISTURE INCREASE IS STILL EXPECTED DURING THIS TIME
PERIOD AS HURRICANE ODILE MOVES NORTHWESTWARD JUST OFF THE WEST
COAST OF BAJA CALIFORNIA. DEEP SE-LY FLOW TO THE EAST AND NORTHEAST
OF ODILE WILL LIKELY PUSH ADDITIONAL MOISTURE NORTHWESTWARD UP THE
GULF OF CALIFORNIA...AND INTO THE DESERT SOUTHWEST. ALTHOUGH THERE
WILL LIKELY BE ENOUGH INCREASE IN AVAILABLE MOISTURE TO TRIGGER AT
LEAST ISOLATED THUNDERSTORMS ACROSS THE LOWER DESERTS OF AZ/SE CA
DURING THIS PERIOD...IT STILL APPEARS THAT WE WILL NOT SEE ANYTHING
CLOSE TO WHAT WE SAW EARLIER THIS WEEK...SINCE LATEST MODEL SUITES
ARE IN VERY STRONG AGREEMENT THAT ODILE WILL TRACK WELL OFF TO OUR
SOUTH AND WEST...EVENTUALLY DISSIPATING OVER THE COOLER WATERS OF
THE EASTERN PACIFIC...WELL OFF THE SOUTHERN CA COAST...WITH MOST OF
ITS ASSOCIATED MOISTURE REMAINING FAR AWAY FROM OUR REGION.
THUS...ONCE AGAIN GOING WITH THE DRIER EURO...WHICH KEEPS OUR PWATS
MAINLY AOB 1.50 INCH THROUGH THIS PERIOD.
&&
.AVIATION...
SOUTH-CENTRAL ARIZONA INCLUDING KPHX...KIWA...AND KSDL...AND
SOUTHEAST CALIFORNIA AND SOUTHWEST ARIZONA INCLUDING KIPL AND KBLH...
NO AVIATION IMPACTS THROUGH FRIDAY MORNING...AS ONLY A FEW AFTERNOON
CU OVER TERRAIN FEATURES WILL PREVAIL ACROSS THE TERMINAL REGION.
SFC WINDS WILL REMAIN VERY LIGHT AOB 10 KT WITH MODERATE CONFIDENCE
OF WIND SHIFT TIMING. IN MANY LOCATIONS AFTER SUNSET...WINDS WILL BE
NEARLY CALM.
AVIATION DISCUSSION NOT UPDATED FOR AMENDED TAFS.
&&
.FIRE WEATHER...
SUNDAY THROUGH THURSDAY...
INCREASING LOW TO MID LEVEL EASTERLY WINDS WILL DEVELOP OVER THE
WEEKEND...HELPING TO SPREAD MONSOONAL MOISTURE AND AN INCREASING
THREAT OF AFTERNOON AND EVENING THUNDERSTORMS BACK OVER THE REGION.
BY SUNDAY A SLIGHT CHANCE OF THUNDERSTORMS IS FORECAST ACROSS THE
ARIZONA DESERTS. HUMIDITY VALUES ACROSS THE DESERTS WILL BEGIN A
STEADY RISE OVER THE WEEKEND AND INTO NEXT WEEK WITH MINIMUM VALUES
FOR MOST AREAS CLIMBING ABOVE 20 PERCENT BY SUNDAY. OVERNIGHT
RECOVERY WILL BE GENERALLY GOOD THROUGH MONDAY WITH MAX HUMIDITY
VALUES CLIMBING ABOVE 50 PERCENT EACH NIGHT...BECOMING GOOD TO
EXCELLENT EARLY NEXT WEEK WITH MANY DESERT LOCALES EXCEEDING 70
PERCENT BY WEDNESDAY MORNING. THE BREEZY EAST WINDS SEEN OVER THE
WEEKEND WILL DIMINISH THROUGH THE MIDDLE OF NEXT WEEK...FAVORING THE
SOUTH TO SOUTHWEST DIRECTIONS AT GENERALLY LESS THAN 15 MPH.
&&
.PSR WATCHES/WARNINGS/ADVISORIES...
AZ...NONE.
CA...NONE.
&&
$$
VISIT US ON FACEBOOK...TWITTER...AND AT WEATHER.GOV/PHOENIX
DISCUSSION...HIRSCH
PREVIOUS DISCUSSION...PERCHA
AVIATION...MO
FIRE WEATHER...MCLANE/CB
AREA FORECAST DISCUSSION
NWS PHOENIX AZ
325 PM MST THU SEP 11 2014
.SYNOPSIS...
THE COMBINATION OF A RATHER DRY AIRMASS AND HIGH PRESSURE ALOFT IS
EXPECTED TO KEEP SKIES MAINLY CLEAR OVER THE REGION THROUGH FRIDAY.
A VERY SLOW INCREASE IN MOISTURE WILL BEGIN LATE FRIDAY...THEN
CONTINUE INTO THE WEEKEND...AND INTO NEXT WEEK AS THE FLOW ALOFT
BECOMES MORE SOUTHEASTERLY. THIS WILL LEAD TO INCREASED CHANCES OF
SHOWERS AND THUNDERSTORMS...INITIALLY OVER MOUNTAINOUS AREAS OVER
THE WEEKEND...BUT POSSIBLY SPREADING INTO LOWER DESERT LOCATIONS BY
EARLY NEXT WEEK.
&&
.DISCUSSION...
LATEST RAP STREAMLINE ANALYSIS SHOWS A WEAK UPPER LEVEL TROUGH
SITUATED ACROSS AZ. SOMEWHAT DEEPER MOISTURE IS EVIDENT ON WV
IMAGERY EAST OF THE TROUGH ACROSS SOUTHERN AND EASTERN AZ...THOUGH
REGIONAL SOUNDINGS INDICATE PWATS ARE ONLY IN THE 1.0-1.2 INCH
RANGE.
ISOLATED CU HAS DEVELOPED ACROSS A FEW RIDGETOPS THIS
AFTERNOON...THOUGH A LACK OF CAPE IS LIMITING VERTICAL DEVELOPMENT.
CONSENSUS OF CONVECTIVE ALLOWING MODELS SUGGESTS THAT ISOLATED
SHOWER AND THUNDERSTORM ACTIVITY WILL REMAIN CONFINED TO SOUTHERN
AND EASTERN AZ THIS AFTERNOON.
CONTINUED WARMING AND DRYING TREND EXPECTED FRIDAY AS THE
SUBTROPICAL RIDGE REMAINS THE PREDOMINANT WEATHER FEATURE.
AGAIN...LITTLE CHANCE FOR CONVECTION EXCEPT FOR ISOLATED ACTIVITY IN
THE VICINITY OF THE DEEPEST MOISTURE ACROSS SOUTHEASTERN AZ.
&&
.PREVIOUS DISCUSSION...
SATURDAY AND SUNDAY...
A SLOW INCREASE IN THE AVAILABLE MOISTURE LEVELS IS STILL EXPECTED
TO OCCUR OVER THE UPCOMING WEEKEND AS THE FLOW BELOW 400MB BECOMES
EASTERLY TO SOUTHEASTERLY...AND BEGINS TO PULL MOISTURE BACK INTO
THE REGION. THE GFS IS MOST BULLISH ON THIS MOISTURE
INCREASE...PUSHING PWATS UP TO NEAR 1.50 ON SATURDAY...WHILE THE
EURO KEEPS THEM MAINLY AOB 1.20 INCH. CONSIDERING THAT THE PRIMARY
REASON FOR THE INCREASE IN THE SFC PRESSURE GRADIENT/EASTERLY FLOW
IN THE LOW LEVELS IS THE FACT THAT A RATHER STRONG...AND QUITE COLD
SFC HIGH IS FORECAST TO DIVE SOUTHWARD INTO THE CENTRAL AND SOUTHERN
PLAINS...WITH ITS ORIGINS BEING FROM NORTHERN CANADA/ALASKA...RATHER
THAN A MORE TYPICAL SUBTROPICAL HIGH THAT OFTEN BUILDS OVER THAT
REGION THIS TIME OF YEAR...I AM INCLINED TO GO WITH THE DRIER EURO
FOR NOW. STILL...THERE SHOULD BE ENOUGH MOISTURE/INSTABILITY TO KEEP
SLIGHT CHANCES FOR SHOWERS/THUNDERSTORMS OVER THE HIGHER TERRAIN
NORTH AND EAST OF PHOENIX IN THE FORECAST...BUT WITH MAINLY SINGLE
DIGIT POPS OVER THE LOWER DESERTS. HIGH TEMPERATURES ARE EXPECTED TO
REMAIN MOSTLY IN THE 105-108F RANGE ACROSS SE CA AND SW AZ...BUT
COOL A DEGREE OR TWO OVER SOUTH-CENTRAL AZ AS A BIT OF COOLER AIR
WORKS ITS WAY IN FROM THE EAST.
MONDAY THROUGH WEDNESDAY...
A FURTHER MOISTURE INCREASE IS STILL EXPECTED DURING THIS TIME
PERIOD AS HURRICANE ODILE MOVES NORTHWESTWARD JUST OFF THE WEST
COAST OF BAJA CALIFORNIA. DEEP SE-LY FLOW TO THE EAST AND NORTHEAST
OF ODILE WILL LIKELY PUSH ADDITIONAL MOISTURE NORTHWESTWARD UP THE
GULF OF CALIFORNIA...AND INTO THE DESERT SOUTHWEST. ALTHOUGH THERE
WILL LIKELY BE ENOUGH INCREASE IN AVAILABLE MOISTURE TO TRIGGER AT
LEAST ISOLATED THUNDERSTORMS ACROSS THE LOWER DESERTS OF AZ/SE CA
DURING THIS PERIOD...IT STILL APPEARS THAT WE WILL NOT SEE ANYTHING
CLOSE TO WHAT WE SAW EARLIER THIS WEEK...SINCE LATEST MODEL SUITES
ARE IN VERY STRONG AGREEMENT THAT ODILE WILL TRACK WELL OFF TO OUR
SOUTH AND WEST...EVENTUALLY DISSIPATING OVER THE COOLER WATERS OF
THE EASTERN PACIFIC...WELL OFF THE SOUTHERN CA COAST...WITH MOST OF
ITS ASSOCIATED MOISTURE REMAINING FAR AWAY FROM OUR REGION.
THUS...ONCE AGAIN GOING WITH THE DRIER EURO...WHICH KEEPS OUR PWATS
MAINLY AOB 1.50 INCH THROUGH THIS PERIOD.
&&
.AVIATION...
SOUTH-CENTRAL ARIZONA INCLUDING KPHX...KIWA...AND KSDL...AND
SOUTHEAST CALIFORNIA AND SOUTHWEST ARIZONA INCLUDING KIPL AND KBLH...
NO AVIATION IMPACTS THROUGH FRIDAY MORNING...AS ONLY A FEW AFTERNOON
CU OVER TERRAIN FEATURES WILL PREVAIL ACROSS THE TERMINAL REGION.
SFC WINDS WILL REMAIN VERY LIGHT AOB 10 KT WITH MODERATE CONFIDENCE
OF WIND SHIFT TIMING. IN MANY LOCATIONS AFTER SUNSET...WINDS WILL BE
NEARLY CALM.
AVIATION DISCUSSION NOT UPDATED FOR AMENDED TAFS.
&&
.FIRE WEATHER...
SATURDAY THROUGH WEDNESDAY.
INCREASING LOW TO MID LEVEL EASTERLY WINDS WILL DEVELOP OVER THE
WEEKEND...HELPING TO SPREAD MONSOONAL MOISTURE AND AN INCREASING
THREAT OF AFTERNOON AND EVENING THUNDERSTORMS BACK OVER THE REGION.
BY SUNDAY A SLIGHT CHANCE OF THUNDERSTORMS IS FORECAST ACROSS THE
ARIZONA DESERTS. HUMIDITY VALUES ACROSS THE DESERTS WILL BEGIN A
STEADY RISE OVER THE WEEKEND AND INTO NEXT WEEK WITH MINIMUM VALUES
FOR MOST AREAS CLIMBING ABOVE 20 PERCENT BY SUNDAY. OVERNIGHT
RECOVERY WILL BE GENERALLY GOOD THROUGH MONDAY WITH MAX HUMIDITY
VALUES CLIMBING ABOVE 50 PERCENT EACH NIGHT...BECOMING GOOD TO
EXCELLENT EARLY NEXT WEEK WITH MANY DESERT LOCALES EXCEEDING 70
PERCENT BY WEDNESDAY MORNING. THE BREEZY EAST WINDS SEEN OVER THE
WEEKEND WILL DIMINISH THROUGH THE MIDDLE OF NEXT WEEK...FAVORING THE
SOUTH TO SOUTHWEST DIRECTIONS AT GENERALLY LESS THAN 15 MPH.
&&
.PSR WATCHES/WARNINGS/ADVISORIES...
AZ...NONE.
CA...NONE.
&&
$$
VISIT US ON FACEBOOK...TWITTER...AND AT WEATHER.GOV/PHOENIX
DISCUSSION...HIRSCH
PREVIOUS DISCUSSION...PERCHA
AVIATION...MO
FIRE WEATHER...MCLANE/CB
AREA FORECAST DISCUSSION
NWS PHOENIX AZ
1255 PM MST THU SEP 11 2014
...UPDATED AVIATION...
.SYNOPSIS...
THE COMBINATION OF A RATHER DRY AIRMASS AND HIGH PRESSURE ALOFT IS
EXPECTED TO KEEP SKIES MAINLY CLEAR OVER THE REGION THROUGH FRIDAY.
A VERY SLOW INCREASE IN MOISTURE WILL BEGIN LATE FRIDAY...THEN
CONTINUE INTO THE WEEKEND...AND INTO NEXT WEEK AS THE FLOW ALOFT
BECOMES MORE SOUTHEASTERLY. THIS WILL LEAD TO INCREASED CHANCES OF
SHOWERS AND THUNDERSTORMS...INITIALLY OVER MOUNTAINOUS AREAS OVER
THE WEEKEND...BUT POSSIBLY SPREADING INTO LOWER DESERT LOCATIONS BY
EARLY NEXT WEEK.
&&
.DISCUSSION...
LATEST RAP STREAMLINE ANALYSIS SHOWS A WEAK UPPER LEVEL TROUGH
SITUATED ACROSS AZ. SOMEWHAT DEEPER MOISTURE IS EVIDENT ON WV
IMAGERY EAST OF THE TROUGH ACROSS SOUTHERN AND EASTERN AZ...THOUGH
REGIONAL SOUNDINGS INDICATE PWATS ARE ONLY IN THE 1.0-1.2 INCH
RANGE. CONSENSUS OF CONVECTIVE ALLOWING MODELS SUGGESTS THAT
ISOLATED SHOWER AND THUNDERSTORM ACTIVITY WILL REMAIN CONFINED TO
THESE AREAS THIS AFTERNOON AND THIS IS REFLECTED IN THE CURRENT
FORECAST. ONLY MINOR ADJUSTMENTS TO THE SHORT-TERM TEMPERATURES AND
DEWPOINTS WERE NEEDED THIS MORNING.
&&
.PREVIOUS DISCUSSION...
TODAY THROUGH FRIDAY...
WESTERLY FLOW ALOFT OVER THE LAST 24-36 HOURS HAS NOW PUSHED ENOUGH
DRY AIR INTO THE REGION TO PUSH PWATS ACROSS MUCH OF OUR REGION TO
AOB 1.00 INCH. AS A RESULT...SKIES HAVE BECOME MOSTLY CLEAR WITH THE
MAIN MOISTURE PLUME NOW DISPLACED WELL TO OUR SOUTH AND
EAST...EXTENDING NORTHEASTWARD FROM NORTHERN MEXICO ACROSS SE NM
INTO W TX. NOT MUCH CHANGE IN THE SENSIBLE WEATHER IS EXPECTED
THROUGH FRIDAY AS WESTERLY FLOW CONTINUES OVER THE REGION. HIGH
TEMPERATURES ARE EXPECTED TO RISE TO NEAR 100 ACROSS THE LOWER
DESERTS TODAY...AND UP INTO THE 103-108F RANGE ON FRIDAY AS 700MB
TEMPS RISE FROM AROUND 11C TODAY TO AROUND 13 ON FRIDAY.
SATURDAY AND SUNDAY...
A SLOW INCREASE IN THE AVAILABLE MOISTURE LEVELS IS STILL EXPECTED
TO OCCUR OVER THE UPCOMING WEEKEND AS THE FLOW BELOW 400MB BECOMES
EASTERLY TO SOUTHEASTERLY...AND BEGINS TO PULL MOISTURE BACK INTO
THE REGION. THE GFS IS MOST BULLISH ON THIS MOISTURE
INCREASE...PUSHING PWATS UP TO NEAR 1.50 ON SATURDAY...WHILE THE
EURO KEEPS THEM MAINLY AOB 1.20 INCH. CONSIDERING THAT THE PRIMARY
REASON FOR THE INCREASE IN THE SFC PRESSURE GRADIENT/EASTERLY FLOW
IN THE LOW LEVELS IS THE FACT THAT A RATHER STRONG...AND QUITE COLD
SFC HIGH IS FORECAST TO DIVE SOUTHWARD INTO THE CENTRAL AND SOUTHERN
PLAINS...WITH ITS ORIGINS BEING FROM NORTHERN CANADA/ALASKA...RATHER
THAN A MORE TYPICAL SUBTROPICAL HIGH THAT OFTEN BUILDS OVER THAT
REGION THIS TIME OF YEAR...I AM INCLINED TO GO WITH THE DRIER EURO
FOR NOW. STILL...THERE SHOULD BE ENOUGH MOISTURE/INSTABILITY TO KEEP
SLIGHT CHANCES FOR SHOWERS/THUNDERSTORMS OVER THE HIGHER TERRAIN
NORTH AND EAST OF PHOENIX IN THE FORECAST...BUT WITH MAINLY SINGLE
DIGIT POPS OVER THE LOWER DESERTS. HIGH TEMPERATURES ARE EXPECTED TO
REMAIN MOSTLY IN THE 105-108F RANGE ACROSS SE CA AND SW AZ...BUT
COOL A DEGREE OR TWO OVER SOUTH-CENTRAL AZ AS A BIT OF COOLER AIR
WORKS ITS WAY IN FROM THE EAST.
MONDAY THROUGH WEDNESDAY...
A FURTHER MOISTURE INCREASE IS STILL EXPECTED DURING THIS TIME
PERIOD AS HURRICANE ODILE MOVES NORTHWESTWARD JUST OFF THE WEST
COAST OF BAJA CALIFORNIA. DEEP SE-LY FLOW TO THE EAST AND NORTHEAST
OF ODILE WILL LIKELY PUSH ADDITIONAL MOISTURE NORTHWESTWARD UP THE
GULF OF CALIFORNIA...AND INTO THE DESERT SOUTHWEST. ALTHOUGH THERE
WILL LIKELY BE ENOUGH INCREASE IN AVAILABLE MOISTURE TO TRIGGER AT
LEAST ISOLATED THUNDERSTORMS ACROSS THE LOWER DESERTS OF AZ/SE CA
DURING THIS PERIOD...IT STILL APPEARS THAT WE WILL NOT SEE ANYTHING
CLOSE TO WHAT WE SAW EARLIER THIS WEEK...SINCE LATEST MODEL SUITES
ARE IN VERY STRONG AGREEMENT THAT ODILE WILL TRACK WELL OFF TO OUR
SOUTH AND WEST...EVENTUALLY DISSIPATING OVER THE COOLER WATERS OF
THE EASTERN PACIFIC...WELL OFF THE SOUTHERN CA COAST...WITH MOST OF
ITS ASSOCIATED MOISTURE REMAINING FAR AWAY FROM OUR REGION.
THUS...ONCE AGAIN GOING WITH THE DRIER EURO...WHICH KEEPS OUR PWATS
MAINLY AOB 1.50 INCH THROUGH THIS PERIOD.
&&
.AVIATION...
SOUTH-CENTRAL ARIZONA INCLUDING KPHX...KIWA...AND KSDL...AND
SOUTHEAST CALIFORNIA AND SOUTHWEST ARIZONA INCLUDING KIPL AND KBLH...
NO AVIATION IMPACTS THROUGH FRIDAY MORNING...AS ONLY A FEW AFTERNOON
CU OVER TERRAIN FEATURES WILL PREVAIL ACROSS THE TERMINAL REGION.
SFC WINDS WILL REMAIN VERY LIGHT AOB 10 KT WITH MODERATE CONFIDENCE
OF WIND SHIFT TIMING. IN MANY LOCATIONS AFTER SUNSET...WINDS WILL BE
NEARLY CALM.
AVIATION DISCUSSION NOT UPDATED FOR AMENDED TAFS.
&&
.FIRE WEATHER...
SATURDAY THROUGH WEDNESDAY.
INCREASING LOW TO MID LEVEL EASTERLY WINDS WILL DEVELOP OVER THE
WEEKEND...HELPING TO SPREAD MONSOONAL MOISTURE AND AN INCREASING
THREAT OF AFTERNOON AND EVENING THUNDERSTORMS BACK OVER THE REGION.
BY SUNDAY A SLIGHT CHANCE OF THUNDERSTORMS IS FORECAST ACROSS THE
ARIZONA DESERTS. HUMIDITY VALUES ACROSS THE DESERTS WILL BEGIN A
STEADY RISE OVER THE WEEKEND AND INTO NEXT WEEK WITH MINIMUM VALUES
FOR MOST AREAS CLIMBING ABOVE 20 PERCENT BY SUNDAY. OVERNIGHT
RECOVERY WILL BE GENERALLY GOOD THROUGH MONDAY WITH MAX HUMIDITY
VALUES CLIMBING ABOVE 50 PERCENT EACH NIGHT...BECOMING GOOD TO
EXCELLENT EARLY NEXT WEEK WITH MANY DESERT LOCALES EXCEEDING 70
PERCENT BY WEDNESDAY MORNING. THE BREEZY EAST WINDS SEEN OVER THE
WEEKEND WILL DIMINISH THROUGH THE MIDDLE OF NEXT WEEK...FAVORING THE
SOUTH TO SOUTHWEST DIRECTIONS AT GENERALLY LESS THAN 15 MPH.
&&
.PSR WATCHES/WARNINGS/ADVISORIES...
AZ...NONE.
CA...NONE.
&&
$$
VISIT US ON FACEBOOK...TWITTER...AND AT WEATHER.GOV/PHOENIX
DISCUSSION...HIRSCH
PREVIOUS DISCUSSION...PERCHA
AVIATION...MO
FIRE WEATHER...MCLANE/CB
AREA FORECAST DISCUSSION
NWS TUCSON AZ
945 AM MST THU SEP 11 2014
.SYNOPSIS...A FEW SHOWERS AND THUNDERSTORMS WILL OCCUR THIS
AFTERNOON AND EVENING MAINLY NEAR THE NEW MEXICO BORDER. EXPECT
ISOLATED TO SCATTERED AFTERNOON AND EVENING THUNDERSTORMS ON FRIDAY
AND CONTINUING INTO NEXT WEEK AS MOISTURE GRADUALLY INCREASES.
WARMER DAYTIME TEMPERATURES WILL PREVAIL THROUGH FRIDAY FOLLOWED BY
MODEST COOLING EARLY THIS WEEKEND.
&&
.DISCUSSION...SUNNY SKIES ACROSS MUCH OF SE AZ AT THIS TIME WITH THE
EXCEPTION OF A FEW CIRRIFORM CLOUDS MAINLY SE OF TUCSON. DEWPOINTS
AT LOWER ELEVATIONS VALID 16Z WERE IN THE MID-UPPER 50S...AND THESE
TEMPS WERE NEARLY 2-5 DEGS F LOWER VERSUS 24 HOURS AGO. SURFACE
TEMPS VALID 16Z WERE ABOUT 2-5 DEGS F WARMER VERSUS THIS TIME WED.
11/12Z KTWC SOUNDING TOTAL PRECIP WATER WAS 1.05 INCHES...AND LIGHT
WLY/SWLY FLOW PREVAILED ABOVE 700 MB.
11/12Z NAM/GFS...11/12Z UNIV OF AZ WRF-NAM...AND THE 11/14Z RUC HRRR
WERE SIMILAR WITH DEPICTING A FEW SHOWERS/TSTMS TO OCCUR THIS
AFTERNOON AND THIS EVENING MAINLY NEAR THE NEW MEXICO BORDER. THE
WRF-NAM AND HRRR WERE ALSO SIMILAR WITH DEPICTING THE INITIAL
DEVELOPMENT OF SHOWERS/TSTMS TO OCCUR ON THE CHIRICAHUA MOUNTAINS
AROUND 18Z-19Z. THESE NWP MODELS DEPICT SHOWERS/TSTMS TO END BY
ABOUT 12/02Z-03Z...OR SHORTLY AFTER SUNSET. ANY RAINFALL AMOUNTS
WILL BE QUITE LIGHT THIS AFTERNOON AND EVENING. OTHERWISE...CLEAR
SKIES OR MOSTLY CLEAR SKIES INTO FRIDAY MORNING WEST OF TUCSON...
AND MOSTLY CLEAR SKIES TO PARTLY CLOUDY SKIES ELSEWHERE. HIGH TEMPS
THIS AFTERNOON WILL BE ABOUT 3-6 DEGS F WARMER ACROSS THE AREA
VERSUS WED.
THERE ARE NO UPDATES PLANNED AT THIS TIME. PLEASE REFER TO THE
ADDITIONAL SECTIONS FOR FURTHER DETAIL.
&&
.AVIATION...VALID THRU 12/12Z.
CLEAR SKIES WILL PREVAIL WEST OF KTUS THRU FRIDAY MORNING. KTUS
VICINITY EASTWARD EXPECT A FEW-SCT CLOUDS AT 8-12K FT AGL MAINLY
THIS AFTERNOON AND EVENING. THERE IS A SLIGHT CHANCE OF -SHRA/-TSRA
MAINLY NEAR THE NEW MEXICO BORDER THIS AFTERNOON AND THIS EVENING.
MOSTLY CLEAR SKIES SHOULD PREVAIL LATE TONIGHT INTO FRIDAY MORNING.
SURFACE WIND WILL GENERALLY BE LESS THAN 10 KTS. AVIATION DISCUSSION
NOT UPDATED FOR TAF AMENDMENTS.
&&
.FIRE WEATHER...THERE IS A SLIGHT CHANCE OF SHOWERS AND
THUNDERSTORMS THIS AFTERNOON AND EVENING MAINLY NEAR THE NEW MEXICO
BORDER. ISOLATED TO SCATTERED AFTERNOON AND EVENING SHOWERS
AND THUNDERSTORMS WILL THEN RETURN STARTING FRIDAY AND CONTINUE INTO
NEXT WEEK AS MOISTURE GRADUALLY INCREASES ACROSS THE AREA. 20-FOOT
WINDS WILL GENERALLY BE LIGHT AND TERRAIN DRIVEN...EXCEPT FOR STRONG
GUSTY OUTFLOWS ASSOCIATED WITH THUNDERSTORMS.
&&
.PREV DISCUSSION...BY FRIDAY INCREASING WINDS TO OUR EAST OVER WEST
TEXAS AND SOUTHERN NEW MEXICO THAT ARE ASSOCIATED WITH THE BOUNDARY/
BACKDOOR FRONT WILL HELP TO USHER IN ADDITIONAL MOISTURE. AS A
RESULT OUR RAIN CHANCES WILL INCREASE...WITH ISOLATED SHOWER AND
THUNDERSTORM ACTIVITY FOR CENTRAL DESERTS...INCLUDING TUCSON AND
SCATTERED ACTIVITY OVER THE EASTERN ZONES BETWEEN TUCSON AND THE NEW
MEXICO BORDER.
FOR SATURDAY AND SUNDAY WE WILL STILL MAINTAIN GENERALLY ISOLATED
POPS FOR MOST AREAS WITH SCATTERED POPS FOR THE WHITE MOUNTAINS.
AS ANOTHER TROPICAL SYSTEM (ODILE)...HEADS TO THE NORTHWEST AND
EVENTUALLY ALONG THE WEST COAST OF THE BAJA PENINSULA...REACHING A
POSITION A COUPLE OF HUNDRED MILES WEST OF THE SOUTH CENTRAL BAJA
PENINSULA BY AROUND LATE MONDAY...WE SHOULD SEE SOME INFLUENCE WITH
AN INCREASE IN SHOWER AND THUNDERSTORM ACTIVITY AS MODELS ARE
SHOWING ACTIVITY DEVELOPING OVER NORTHERN MEXICO AND INTO PARTS OF
SOUTHERN ARIZONA. HOWEVER...THE WINDS IN THIS CASE WILL USHER
MOISTURE MOSTLY TO THE WEST OR WEST NORTHWEST...KEEPING THE BULK OF
THE SHOWERS AND THUNDERSTORMS TO OUR SOUTH. THAT SAID...JUST HAVE
CHANCE CATEGORY POPS ALONG THE INTERNATIONAL BORDER BEGINNING MONDAY
AND CONTINUING THROUGH THE MIDDLE OF NEXT WEEK. MORE NORTHERN PARTS
OF MY FORECAST AREA WILL STILL SEE SLIGHT CHANCE TYPE POPS FOR
DESERTS/VALLEYS AND CHANCE POPS FOR THE MOUNTAINS DURING THAT
PERIOD. OF COURSE THE FORECAST FOR NEXT WEEK WILL CONTINUALLY BE
REEVALUATED WITH EACH NEW MODEL RUN...SO STAY TUNED FOR CHANGES AND
ENHANCEMENTS TO THE FORECAST BETWEEN NOW AND EARLY NEXT WEEK.
HIGH TEMPERATURES WILL GENERALLY BE 1 TO 3 DEGS ABOVE NORMAL TODAY
AND ESPECIALLY FRIDAY...THEN NEAR OR SLIGHTLY BELOW NORMAL FOR
SATURDAY. THEREAFTER...HIGHS AT OR SLIGHTLY ABOVE NORMAL EACH DAY.
LOW TEMPS WILL BE SEVERAL DEGREES ABOVE NORMAL EACH MORNING.
&&
.TWC WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
VISIT US ON FACEBOOK...TWITTER...YOUTUBE...AND AT WEATHER.GOV/TUCSON
DISCUSSION...FRANCIS
PREVIOUS DISCUSSION...MOLLERE
AREA FORECAST DISCUSSION
NWS PHOENIX AZ
930 AM MST THU SEP 11 2014
.SYNOPSIS...
THE COMBINATION OF A RATHER DRY AIRMASS AND HIGH PRESSURE ALOFT IS
EXPECTED TO KEEP SKIES MAINLY CLEAR OVER THE REGION THROUGH FRIDAY.
A VERY SLOW INCREASE IN MOISTURE WILL BEGIN LATE FRIDAY...THEN
CONTINUE INTO THE WEEKEND...AND INTO NEXT WEEK AS THE FLOW ALOFT
BECOMES MORE SOUTHEASTERLY. THIS WILL LEAD TO INCREASED CHANCES OF
SHOWERS AND THUNDERSTORMS...INITIALLY OVER MOUNTAINOUS AREAS OVER
THE WEEKEND...BUT POSSIBLY SPREADING INTO LOWER DESERT LOCATIONS BY
EARLY NEXT WEEK.
&&
.DISCUSSION...
LATEST RAP STREAMLINE ANALYSIS SHOWS A WEAK UPPER LEVEL TROUGH
SITUATED ACROSS AZ. SOMEWHAT DEEPER MOISTURE IS EVIDENT ON WV
IMAGERY EAST OF THE TROUGH ACROSS SOUTHERN AND EASTERN AZ...THOUGH
REGIONAL SOUNDINGS INDICATE PWATS ARE ONLY IN THE 1.0-1.2 INCH
RANGE. CONSENSUS OF CONVECTIVE ALLOWING MODELS SUGGESTS THAT
ISOLATED SHOWER AND THUNDERSTORM ACTIVITY WILL REMAIN CONFINED TO
THESE AREAS THIS AFTERNOON AND THIS IS REFLECTED IN THE CURRENT
FORECAST. ONLY MINOR ADJUSTMENTS TO THE SHORT-TERM TEMPERATURES AND
DEWPOINTS WERE NEEDED THIS MORNING.
&&
.PREVIOUS DISCUSSION...
TODAY THROUGH FRIDAY...
WESTERLY FLOW ALOFT OVER THE LAST 24-36 HOURS HAS NOW PUSHED ENOUGH
DRY AIR INTO THE REGION TO PUSH PWATS ACROSS MUCH OF OUR REGION TO
AOB 1.00 INCH. AS A RESULT...SKIES HAVE BECOME MOSTLY CLEAR WITH THE
MAIN MOISTURE PLUME NOW DISPLACED WELL TO OUR SOUTH AND
EAST...EXTENDING NORTHEASTWARD FROM NORTHERN MEXICO ACROSS SE NM
INTO W TX. NOT MUCH CHANGE IN THE SENSIBLE WEATHER IS EXPECTED
THROUGH FRIDAY AS WESTERLY FLOW CONTINUES OVER THE REGION. HIGH
TEMPERATURES ARE EXPECTED TO RISE TO NEAR 100 ACROSS THE LOWER
DESERTS TODAY...AND UP INTO THE 103-108F RANGE ON FRIDAY AS 700MB
TEMPS RISE FROM AROUND 11C TODAY TO AROUND 13 ON FRIDAY.
SATURDAY AND SUNDAY...
A SLOW INCREASE IN THE AVAILABLE MOISTURE LEVELS IS STILL EXPECTED
TO OCCUR OVER THE UPCOMING WEEKEND AS THE FLOW BELOW 400MB BECOMES
EASTERLY TO SOUTHEASTERLY...AND BEGINS TO PULL MOISTURE BACK INTO
THE REGION. THE GFS IS MOST BULLISH ON THIS MOISTURE
INCREASE...PUSHING PWATS UP TO NEAR 1.50 ON SATURDAY...WHILE THE
EURO KEEPS THEM MAINLY AOB 1.20 INCH. CONSIDERING THAT THE PRIMARY
REASON FOR THE INCREASE IN THE SFC PRESSURE GRADIENT/EASTERLY FLOW
IN THE LOW LEVELS IS THE FACT THAT A RATHER STRONG...AND QUITE COLD
SFC HIGH IS FORECAST TO DIVE SOUTHWARD INTO THE CENTRAL AND SOUTHERN
PLAINS...WITH ITS ORIGINS BEING FROM NORTHERN CANADA/ALASKA...RATHER
THAN A MORE TYPICAL SUBTROPICAL HIGH THAT OFTEN BUILDS OVER THAT
REGION THIS TIME OF YEAR...I AM INCLINED TO GO WITH THE DRIER EURO
FOR NOW. STILL...THERE SHOULD BE ENOUGH MOISTURE/INSTABILITY TO KEEP
SLIGHT CHANCES FOR SHOWERS/THUNDERSTORMS OVER THE HIGHER TERRAIN
NORTH AND EAST OF PHOENIX IN THE FORECAST...BUT WITH MAINLY SINGLE
DIGIT POPS OVER THE LOWER DESERTS. HIGH TEMPERATURES ARE EXPECTED TO
REMAIN MOSTLY IN THE 105-108F RANGE ACROSS SE CA AND SW AZ...BUT
COOL A DEGREE OR TWO OVER SOUTH-CENTRAL AZ AS A BIT OF COOLER AIR
WORKS ITS WAY IN FROM THE EAST.
MONDAY THROUGH WEDNESDAY...
A FURTHER MOISTURE INCREASE IS STILL EXPECTED DURING THIS TIME
PERIOD AS HURRICANE ODILE MOVES NORTHWESTWARD JUST OFF THE WEST
COAST OF BAJA CALIFORNIA. DEEP SE-LY FLOW TO THE EAST AND NORTHEAST
OF ODILE WILL LIKELY PUSH ADDITIONAL MOISTURE NORTHWESTWARD UP THE
GULF OF CALIFORNIA...AND INTO THE DESERT SOUTHWEST. ALTHOUGH THERE
WILL LIKELY BE ENOUGH INCREASE IN AVAILABLE MOISTURE TO TRIGGER AT
LEAST ISOLATED THUNDERSTORMS ACROSS THE LOWER DESERTS OF AZ/SE CA
DURING THIS PERIOD...IT STILL APPEARS THAT WE WILL NOT SEE ANYTHING
CLOSE TO WHAT WE SAW EARLIER THIS WEEK...SINCE LATEST MODEL SUITES
ARE IN VERY STRONG AGREEMENT THAT ODILE WILL TRACK WELL OFF TO OUR
SOUTH AND WEST...EVENTUALLY DISSIPATING OVER THE COOLER WATERS OF
THE EASTERN PACIFIC...WELL OFF THE SOUTHERN CA COAST...WITH MOST OF
ITS ASSOCIATED MOISTURE REMAINING FAR AWAY FROM OUR REGION.
THUS...ONCE AGAIN GOING WITH THE DRIER EURO...WHICH KEEPS OUR PWATS
MAINLY AOB 1.50 INCH THROUGH THIS PERIOD.
&&
AVIATION...
SOUTH-CENTRAL ARIZONA...SOUTHEAST CALIFORNIA AND SOUTHWEST ARIZONA
INCLUDING KPHX...KIWA...KSDL...KIPL...AND KBLH...
HIGH PRESSURE ALOFT CONTINUES TO BUILD ACROSS THE LOWER DESERTS...AS
AS THIS OCCURS DRIER AIR WILL FILTER IN FROM THE WEST. AS
SUCH...EXPECT GENERALLY CLEAR SKIES NEXT 24 HOURS WITH POSSIBLY A
FEW CU DECKS DURING THE AFTERNOON HOURS AT THE TAF SITES...WITH
BASES AOA 6K FEET. OTHERWISE...WINDS TO BE QUITE LIGHT AND VARIABLE
AT THE TERMINALS...OCCASIONALLY FOLLOWING NORMAL DIURNAL DIRECTIONS.
NO AVIATION IMPACTS EXPECTED NEXT 24 HOURS WITH VFR CONDITIONS AT
ALL TERMINALS THROUGH FRIDAY MORNING.
AVIATION DISCUSSION NOT UPDATED FOR AMENDED TAFS.
&&
.FIRE WEATHER...
SATURDAY THROUGH WEDNESDAY.
INCREASING LOW TO MID LEVEL EASTERLY WINDS WILL DEVELOP OVER THE
WEEKEND...HELPING TO SPREAD MONSOONAL MOISTURE AND AN INCREASING
THREAT OF AFTERNOON AND EVENING THUNDERSTORMS BACK OVER THE REGION.
BY SUNDAY A SLIGHT CHANCE OF THUNDERSTORMS IS FORECAST ACROSS THE
ARIZONA DESERTS. HUMIDITY VALUES ACROSS THE DESERTS WILL BEGIN A
STEADY RISE OVER THE WEEKEND AND INTO NEXT WEEK WITH MINIMUM VALUES
FOR MOST AREAS CLIMBING ABOVE 20 PERCENT BY SUNDAY. OVERNIGHT
RECOVERY WILL BE GENERALLY GOOD THROUGH MONDAY WITH MAX HUMIDITY
VALUES CLIMBING ABOVE 50 PERCENT EACH NIGHT...BECOMING GOOD TO
EXCELLENT EARLY NEXT WEEK WITH MANY DESERT LOCALES EXCEEDING 70
PERCENT BY WEDNESDAY MORNING. THE BREEZY EAST WINDS SEEN OVER THE
WEEKEND WILL DIMINISH THROUGH THE MIDDLE OF NEXT WEEK...FAVORING THE
SOUTH TO SOUTHWEST DIRECTIONS AT GENERALLY LESS THAN 15 MPH.
&&
.PSR WATCHES/WARNINGS/ADVISORIES...
AZ...NONE.
CA...NONE.
&&
$$
VISIT US ON FACEBOOK...TWITTER...AND AT WEATHER.GOV/PHOENIX
DISCUSSION...HIRSCH
PREVIOUS DISCUSSION...PERCHA
AVIATION...CB
FIRE WEATHER...MCLANE/CB
AREA FORECAST DISCUSSION
NWS PUEBLO CO
551 PM MDT FRI SEP 12 2014
.UPDATE...
ISSUED AT 549 PM MDT FRI SEP 12 2014
LOOKING AT SAT PIX...AND HI RES RH FIELDS IN THE LOWER LVLS OF THE
ATMOSPHERE AND PRGD SOUNDINGS...HAVE PLAYED UP MORE LOW CLOUDS FOR
TONIGHT THAN WERE IN EARLIER FCST PRODUCTS. FCST ARE BEING UPDATED
AS I WRITE.
&&
.SHORT TERM...(THIS EVENING THROUGH SATURDAY)
ISSUED AT 242 PM MDT FRI SEP 12 2014
WIDESPREAD LOW CLOUDS CONTINUE TO COVER THE SERN CO PLAINS THIS
AFTERNOON...WITH TEMPS IN THE 40S. THE REST OF THE FORECAST AREA
HAS HAD MOSTLY SUNNY SKIES...WITH SOME CONVECTIVE CLOUDS DEVELOPING
OVER THE SRN MTNS AND SAN LUIS VALLEY. THERE CONTINUES TO BE SOME
SPOTTY LIGHT DRIZZLE IN LOCATIONS NR THE ERN MTNS. THE NAM HAS WAY
OVERDONE THE PCPN OVR THE SERN PLAINS FOR TODAY...WITH THE HRRR
BEING MORE REASONABLE. FOR THIS EVENING AND OVERNIGHT THE NAM
PRINTS OUT SOME ISOLD PCPN OVR THE SRN CO MTNS. THE HRRR IS DRY FOR
THIS EVENING. IT IS POSSIBLE THAT A FEW SHOWERS COULD DEVELOP FOR
THE EVENING HOURS...BUT FOR NOW WL LEAVE SILENT POPS IN THE
FORECAST. THE NAM AND HRRR ARE STILL SHOWING A DECREASE IN LOW LEVEL
CLOUD COVER LATER THIS AFTERNOON AND EARLY THIS EVENING...BUT NOT
SEEING ANY EVIDENCE OF THIS IN THE SATELLITE IMAGES YET. BOTH MODELS
THEN SHOW THE POTENTIAL FOR LOW CLOUD REFORMING OVR PORTIONS OF THE
PLAINS BY LATE EVENING. OVERNIGHT LOW TEMPS ARE EXPECTED TO BE IN
THE UPPER 30S TO LOWER 40S OVR THE SERN PLAINS...THE COLDEST AREAS
LOOK TO BE NORTHERN PORTIONS OF PUEBLO COUNTY...EL PASO AND CROWLEY
COUNTIES. LOWS IN THESE LOCATIONS LOOK LIKE THEY WL BE IN THE LOWER
30S. HAVE DECIDED TO ISSUE A FROST ADVISORY FOR THESE COUNTIES JUST
IN CASE THERE ARE POCKETS OF FROST.
MODELS ARE INDICATING THAT THE LOW CLOUDS SHOULD DISSIPATE BY LATE
MORNING ON SATURDAY WITH A GOOD WARM UP IN STORE. HIGHS ON SAT OVR
THE SERN PLAINS SHOULD BE IN THE 70S...WITH MID TO UPPER 70S IN THE
SAN LUIS VALLEY. GENERALLY DRY WESTERLY FLOW ALOFT IS EXPECTED OVR
THE FORECAST AREA. THE NAM AGAIN PRINTS OUT SOME LIGHT PCPN OVR THE
SRN CO MTNS AND SAN LUIS VALLEY SAT AFTERNOON...SO WL LEAVE SOME
ISOLD POPS IN THE FORECAST FOR THE SW MTNS AND THE SANGRES.
.LONG TERM...(SATURDAY NIGHT THROUGH FRIDAY)
ISSUED AT 242 PM MDT FRI SEP 12 2014
MODELS IN GOOD AGREEMENT THROUGH THE EXTENDED PERIOD WITH SMALL
ENSEMBLE SPREADS AND HIGHER FORECAST CONFIDENCE.
SATURDAY NIGHT THROUGH SUNDAY NIGHT...FLAT ZONAL WESTERLY FLOW
WILL PERSIST ACROSS COLORADO THROUGH THIS PERIOD AS AN UPPER RIDGE
BEGINS TO BUILD ALONG THE WEST COAST AND SHORTWAVE TROUGH DROPS
SOUTH OUT OF CANADA INTO THE NORTHERN PLAINS. EXPECT ISOLATED
SHOWERS AND THUNDERSTORMS OVER THE MOUNTAINS ON SATURDAY EVENING
TO DISSIPATE AROUND SUNDOWN WITH LOSS OF DAYTIME INSTABILITY.
OVERNIGHT LOWS WILL FALL INTO THE MID TO UPPER 40S FOR MUCH OF THE
REGION. A WEAK DISTURBANCE EMBEDDED IN THE WESTERLY FLOW ALOFT
WILL MOVE ACROSS THE STATE ON SUNDAY AFTERNOON. ANOTHER ROUND OF
ISOLATED TO SCATTERED MOUNTAIN SHOWERS AND THUNDERSTORMS ARE
EXPECTED...WHICH SHOULD DISSIPATE ON SUNDAY EVENING. HIGHS SUNDAY
WILL REACH INTO THE 80S FOR THE LOWER ELEVATIONS.
MONDAY AND MONDAY NIGHT...MODELS IN GOOD AGREEMENT WITH A STRONG
COLD FRONT DROPPING SOUTH ACROSS THE EASTERN PLAINS ON MONDAY
MORNING. THE NAM IS THE FASTEST SOLUTION...WITH IT CLEARING SOUTH
INTO NEW MEXICO BY 12Z...WHILE THE ECMWF AND GFS ARE ABOUT 6 HOURS
SLOWER. FEEL THAT A BIT FASTER SOLUTIONS WILL LIKELY PLAY OUT AND
FOLLOWED THE NAM FRONTAL PROGRESSION. EXPECT LOW LEVEL FLOW TO
TURN EASTERLY AND USHER IN MUCH COOLER AIR INTO THE PLAINS.
UPGLIDE AND MOISTURE BEHIND THE FRONT WILL LIKELY LEAD TO LIGHT
RAIN FOR THE PLAINS THROUGH MONDAY AFTERNOON. WARMER TEMPERATURES
AND GREATER INSTABILITY WILL EXIST OVER THE MOUNTAIN AREAS MONDAY
AFTERNOON AND SCATTERED SHOWERS AND THUNDERSTORMS ARE EXPECTED.
MODELS IN AGREEMENT WITH THE LIGHT RAIN COMING TO AN END FOR THE
PLAINS FROM NORTH TO SOUTH THROUGH THE AFTERNOON HOURS. EXPECT
THUNDERSTORMS OVER THE MOUNTAINS TO DISSIPATE AFTER SUNSET.
TEMPERATURES WILL BE MUCH COOLER BEHIND THE FRONT WITH THE PLAINS
LIKELY ONLY SEEING 60S FOR HIGHS.
TUESDAY THROUGH FRIDAY...THE UPPER PATTERN WILL BECOME AMPLIFIED
ACROSS THE CONUS WITH HIGH PRESSURE BUILDING OVER THE WEST AND A
TROUGH OVER THE EASTERN STATES. THIS WILL PUT SOUTHERN COLORADO
UNDER BROAD NORTHWEST FLOW. EXPECT GENERALLY DRY CONDITIONS ACROSS
THE REGION WITH DAILY AFTERNOON AND EVENING MOUNTAIN CONVECTION
POSSIBLE. TEMPERATURES WILL BE QUICK TO WARM UP WITH 80S FOR THE
LOWER ELEVATIONS THROUGH THE MIDDLE OF THE WEEK.
BY FRIDAY MODELS ARE BRINGING A PIECE OF ENERGY FROM TROPICAL
STORM ODILE WHICH IS FORECAST TO BE OFF THE NORTHERN BAJA COAST BY
FRIDAY. IF THIS DISTURBANCE AND MOISTURE DOES MATERIALIZE...THERE
WILL BE MUCH BETTER CHANCES FOR PRECIPITATION...ESPECIALLY ALONG
THE CONTINENTAL DIVIDE...BY FRIDAY. THIS WILL NEED TO BE
MONITORED. MOZLEY
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z SUNDAY EVENING) ISSUED
AT 522 PM MDT FRI SEP 12 2014
LATEST GUIDANCE KEEPS KCOS AND KPUB SOCKED IN FOR TONIGHT AND
HAVE ADJUSTED TAFS ACCORDINGLY. GUIDANCE LOOKS
REASONABLE...ESPECIALLY FOR KCOS...AS SOUTHERLY WINDS ARE
PROJECTED TO OCCUR THROUGHOUT THE NIGHT TIME HOURS.
&&
.PUB WATCHES/WARNINGS/ADVISORIES...
FROST ADVISORY FROM 1 AM TO 8 AM MDT SATURDAY FOR COZ084>086-089.
&&
$$
UPDATE...HODANISH
SHORT TERM...28
LONG TERM...MOZLEY
AVIATION...HODANISH
AREA FORECAST DISCUSSION
NWS PUEBLO CO
526 PM MDT FRI SEP 12 2014
.SHORT TERM...(THIS EVENING THROUGH SATURDAY)
ISSUED AT 242 PM MDT FRI SEP 12 2014
WIDESPREAD LOW CLOUDS CONTINUE TO COVER THE SERN CO PLAINS THIS
AFTERNOON...WITH TEMPS IN THE 40S. THE REST OF THE FORECAST AREA
HAS HAD MOSTLY SUNNY SKIES...WITH SOME CONVECTIVE CLOUDS DEVELOPING
OVER THE SRN MTNS AND SAN LUIS VALLEY. THERE CONTINUES TO BE SOME
SPOTTY LIGHT DRIZZLE IN LOCATIONS NR THE ERN MTNS. THE NAM HAS WAY
OVERDONE THE PCPN OVR THE SERN PLAINS FOR TODAY...WITH THE HRRR
BEING MORE REASONABLE. FOR THIS EVENING AND OVERNIGHT THE NAM
PRINTS OUT SOME ISOLD PCPN OVR THE SRN CO MTNS. THE HRRR IS DRY FOR
THIS EVENING. IT IS POSSIBLE THAT A FEW SHOWERS COULD DEVELOP FOR
THE EVENING HOURS...BUT FOR NOW WL LEAVE SILENT POPS IN THE
FORECAST. THE NAM AND HRRR ARE STILL SHOWING A DECREASE IN LOW LEVEL
CLOUD COVER LATER THIS AFTERNOON AND EARLY THIS EVENING...BUT NOT
SEEING ANY EVIDENCE OF THIS IN THE SATELLITE IMAGES YET. BOTH MODELS
THEN SHOW THE POTENTIAL FOR LOW CLOUD REFORMING OVR PORTIONS OF THE
PLAINS BY LATE EVENING. OVERNIGHT LOW TEMPS ARE EXPECTED TO BE IN
THE UPPER 30S TO LOWER 40S OVR THE SERN PLAINS...THE COLDEST AREAS
LOOK TO BE NORTHERN PORTIONS OF PUEBLO COUNTY...EL PASO AND CROWLEY
COUNTIES. LOWS IN THESE LOCATIONS LOOK LIKE THEY WL BE IN THE LOWER
30S. HAVE DECIDED TO ISSUE A FROST ADVISORY FOR THESE COUNTIES JUST
IN CASE THERE ARE POCKETS OF FROST.
MODELS ARE INDICATING THAT THE LOW CLOUDS SHOULD DISSIPATE BY LATE
MORNING ON SATURDAY WITH A GOOD WARM UP IN STORE. HIGHS ON SAT OVR
THE SERN PLAINS SHOULD BE IN THE 70S...WITH MID TO UPPER 70S IN THE
SAN LUIS VALLEY. GENERALLY DRY WESTERLY FLOW ALOFT IS EXPECTED OVR
THE FORECAST AREA. THE NAM AGAIN PRINTS OUT SOME LIGHT PCPN OVR THE
SRN CO MTNS AND SAN LUIS VALLEY SAT AFTERNOON...SO WL LEAVE SOME
ISOLD POPS IN THE FORECAST FOR THE SW MTNS AND THE SANGRES.
.LONG TERM...(SATURDAY NIGHT THROUGH FRIDAY)
ISSUED AT 242 PM MDT FRI SEP 12 2014
MODELS IN GOOD AGREEMENT THROUGH THE EXTENDED PERIOD WITH SMALL
ENSEMBLE SPREADS AND HIGHER FORECAST CONFIDENCE.
SATURDAY NIGHT THROUGH SUNDAY NIGHT...FLAT ZONAL WESTERLY FLOW
WILL PERSIST ACROSS COLORADO THROUGH THIS PERIOD AS AN UPPER RIDGE
BEGINS TO BUILD ALONG THE WEST COAST AND SHORTWAVE TROUGH DROPS
SOUTH OUT OF CANADA INTO THE NORTHERN PLAINS. EXPECT ISOLATED
SHOWERS AND THUNDERSTORMS OVER THE MOUNTAINS ON SATURDAY EVENING
TO DISSIPATE AROUND SUNDOWN WITH LOSS OF DAYTIME INSTABILITY.
OVERNIGHT LOWS WILL FALL INTO THE MID TO UPPER 40S FOR MUCH OF THE
REGION. A WEAK DISTURBANCE EMBEDDED IN THE WESTERLY FLOW ALOFT
WILL MOVE ACROSS THE STATE ON SUNDAY AFTERNOON. ANOTHER ROUND OF
ISOLATED TO SCATTERED MOUNTAIN SHOWERS AND THUNDERSTORMS ARE
EXPECTED...WHICH SHOULD DISSIPATE ON SUNDAY EVENING. HIGHS SUNDAY
WILL REACH INTO THE 80S FOR THE LOWER ELEVATIONS.
MONDAY AND MONDAY NIGHT...MODELS IN GOOD AGREEMENT WITH A STRONG
COLD FRONT DROPPING SOUTH ACROSS THE EASTERN PLAINS ON MONDAY
MORNING. THE NAM IS THE FASTEST SOLUTION...WITH IT CLEARING SOUTH
INTO NEW MEXICO BY 12Z...WHILE THE ECMWF AND GFS ARE ABOUT 6 HOURS
SLOWER. FEEL THAT A BIT FASTER SOLUTIONS WILL LIKELY PLAY OUT AND
FOLLOWED THE NAM FRONTAL PROGRESSION. EXPECT LOW LEVEL FLOW TO
TURN EASTERLY AND USHER IN MUCH COOLER AIR INTO THE PLAINS.
UPGLIDE AND MOISTURE BEHIND THE FRONT WILL LIKELY LEAD TO LIGHT
RAIN FOR THE PLAINS THROUGH MONDAY AFTERNOON. WARMER TEMPERATURES
AND GREATER INSTABILITY WILL EXIST OVER THE MOUNTAIN AREAS MONDAY
AFTERNOON AND SCATTERED SHOWERS AND THUNDERSTORMS ARE EXPECTED.
MODELS IN AGREEMENT WITH THE LIGHT RAIN COMING TO AN END FOR THE
PLAINS FROM NORTH TO SOUTH THROUGH THE AFTERNOON HOURS. EXPECT
THUNDERSTORMS OVER THE MOUNTAINS TO DISSIPATE AFTER SUNSET.
TEMPERATURES WILL BE MUCH COOLER BEHIND THE FRONT WITH THE PLAINS
LIKELY ONLY SEEING 60S FOR HIGHS.
TUESDAY THROUGH FRIDAY...THE UPPER PATTERN WILL BECOME AMPLIFIED
ACROSS THE CONUS WITH HIGH PRESSURE BUILDING OVER THE WEST AND A
TROUGH OVER THE EASTERN STATES. THIS WILL PUT SOUTHERN COLORADO
UNDER BROAD NORTHWEST FLOW. EXPECT GENERALLY DRY CONDITIONS ACROSS
THE REGION WITH DAILY AFTERNOON AND EVENING MOUNTAIN CONVECTION
POSSIBLE. TEMPERATURES WILL BE QUICK TO WARM UP WITH 80S FOR THE
LOWER ELEVATIONS THROUGH THE MIDDLE OF THE WEEK.
BY FRIDAY MODELS ARE BRINGING A PIECE OF ENERGY FROM TROPICAL
STORM ODILE WHICH IS FORECAST TO BE OFF THE NORTHERN BAJA COAST BY
FRIDAY. IF THIS DISTURBANCE AND MOISTURE DOES MATERIALIZE...THERE
WILL BE MUCH BETTER CHANCES FOR PRECIPITATION...ESPECIALLY ALONG
THE CONTINENTAL DIVIDE...BY FRIDAY. THIS WILL NEED TO BE
MONITORED. MOZLEY
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z SUNDAY EVENING) ISSUED
AT 522 PM MDT FRI SEP 12 2014
LATEST GUIDANCE KEEPS KCOS AND KPUB SOCKED IN FOR TONIGHT AND
HAVE ADJUSTED TAFS ACCORDINGLY. GUIDANCE LOOKS
REASONABLE...ESPECIALLY FOR KCOS...AS SOUTHERLY WINDS ARE
PROJECTED TO OCCUR THROUGHOUT THE NIGHT TIME HOURS.
&&
.PUB WATCHES/WARNINGS/ADVISORIES...
FROST ADVISORY FROM 1 AM TO 8 AM MDT SATURDAY FOR COZ084>086-089.
&&
$$
SHORT TERM...28
LONG TERM...MOZLEY
AVIATION...HODANISH
AREA FORECAST DISCUSSION
NWS ALBANY NY
736 AM EDT THU SEP 11 2014
.SYNOPSIS...
LOW PRESSURE IN EASTERN CANADA WILL DRIVE A COLD FRONT ACROSS THE
REGION THIS AFTERNOON. AHEAD OF THIS FRONT WILL BE SCATTERED SHOWERS
AND PERHAPS A THUNDERSTORM...MAINLY SOUTH OF ALBANY. BEHIND THIS
FRONT WILL COME THE COOLEST AIR MASS SINCE LATE MAY BY FRIDAY. A
DISTURBANCE MIGHT BRING A ROUND OF SHOWERS ON SATURDAY FOLLOWED BY
MORE COOL DRY WEATHER SUNDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
AS OF 630 AM EDT...SCATTERED MAINLY LIGHT SHOWERS WERE WORKING INTO
MUCH OF THE AREA. THIS BATCH WILL LEAVE BUT OTHERS WILL THROUGHOUT
THE DAY. LOW PRESSURE WAS WORKING THROUGH SOUTHERN ONTARIO DRAGGING
AA COLD FRONT INTO WESTERN NEW YORK.
FOR THIS UPDATE...JUST INCREASED HOURLY POPS A BIT THIS MORNING (DUE
TO THE SCATTERED SHOWERS MOVING QUICKLY EAST). OTHERWISE VERY LITTLE
TO TWEAK OTHER THAN THAT.
THE LATEST RUC13 INDICATED LITTLE OR NO INSTABILITY SO WE KEPT ANY
MENTION OF THUNDER OUT OF THE FORECAST THROUGH EARLY MORNING.
TEMPERATURES WERE QUITE MILD DUE TO AN INCREASE IN CLOUDS...AND A
PERSISTENT SOUTHERLY BREEZE ON THE WARM SIDE OF THE LOW
PRESSURE...HOLDING MAINLY IN THE 60S.
THE AFOREMENTIONED COLD FRONT ASSOCIATED WITH THE LOW PRESSURE WILL
MOVE STEADILY ALONG AND WORK INTO THE SOUTHERN ADIRONDACKS AND THE
MOHAWK VALLEY EARLY THIS AFTERNOON...THE CAPITAL REGION AND
SURROUNDING AREAS LATE AFTERNOON...AND THE MID HUDSON VALLEY AND
NORTHWESTERN CONNECTICUT BY EARLY EVENING.
DUE TO VERY LIMITED INSTABILITY WE ONLY MENTION A SLIGHT CHANCE OF
THUNDERSTORM FROM THE CAPITAL REGION NORTHWARD. FURTHER SOUTH...WITH
A LITTLE MORE INSTABILITY...WE DID MENTION A CHANCE OF
THUNDERSTORMS. IT IS REMOTELY POSSIBLE THAT ANY THUNDERSTORM IN THIS
AREA COULD CONTAIN SOME GUSTY WINDS AS THE OVERALL WIND FIELD (BULK
SHEAR) INCREASES TO ABOUT 35-40KTS. HOWEVER...THE THREAT APPEARED
LOW ENOUGH NOT TO MENTION IN THE GRIDS OR CERTAINLY ENHANCED WORDING
AT THIS TIME.
PWAT VALUES LOOK TO INCREASE TO ABOUT 2 INCHES...BUT THIS LOOKS TO
HAPPEN THIS MORNING. THE H20 WATER VAPOR LOOP ALREADY INDICATED A
MID LEVEL DRY PUNCH QUICKLY WORKING INTO WESTERN NEW YORK STATE.
THIS DRY PUNCH WILL ALLOW PWATS TO DROP QUICKLY THIS
AFTERNOON...EVEN AHEAD OF THE FRONT. THEREFORE THE BEST FORCING
(WHICH IS GOING TO WELL NORTH)...WILL NOT LINE UP WITH THE BEST
PWATS AND PASSAGE OF THE COLD FRONT.
THERE WILL BE PLENTY OF CLOUDS TODAY WITH PERHAPS A FEW BREAKS OF
AFTERNOON SUNSHINE. EVEN SO...TEMPERATURES COULD SPIKE A LITTLE
AHEAD OF THE FRONT. WE EXPECT HIGHS NEAR 80 IN THE MID HUDSON VALLEY
AND LOWER LITCHFIELD COUNTY...UPPER 70S AROUND ALBANY. FURTHER NORTH
AND WEST WHERE THE COLD FRONT WILL BE FIRST TO COME THROUGH...HIGH
TEMPERATURES WILL BE HELD TO BETWEEN THE UPPER 60S TO MID 70S.
A GUSTY SOUTH WIND PREVAIL TODAY 10 TO 20 MPH...SHIFTING TO THE WEST
BY LATE IN THE DAY ONCE THE COLD FRONT MOVES THROUGH.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH SATURDAY NIGHT/...
THE COLD FRONT WILL BE FINISHING ITS SWEEP THROUGH OUR AREA THIS
EVENING TAKING ANY LEFTOVER SHOWERS WITH IT.
THEN...A COOL CANADIAN AIR MASS WILL BE USHERED IN TONIGHT ON
SOMEWHAT GUSTY NORTH OR NORTHWEST WINDS. THE SKY WILL CLEAR AND
TEMPERATURES WILL DIP DOWN TO AROUND 50 FROM ALBANY SOUTH AND EAST.
FURTHER NORTHWEST AND WEST...THEY WILL DIVE INTO THE 40S...AND EVEN
TOUCH THE UPPER 30S ACROSS OUR ADIRONDACKS.
FRIDAY LOOKS TO FEATURE A GOOD DEAL OF SUNSHINE (MIXING WITH FAIR
WEATHER STRATO-CUMULUS) AND TEMPERATURES BELOW NORMAL. H850
TEMPERATURES LOOK TO DROP TO BETWEEN +5C NORTHWEST TO +9C SOUTHEAST
ACROSS OUR REGION. THIS WILL TRANSLATE TO HIGH TEMPERATURES MAINLY
IN THE 60S THROUGH OUR REGION...PERHAPS TOUCHING 70 FROM
POUGHKEEPSIE...BUT ONLY 50S ACROSS THE ELEVATED TERRAIN NORTH OF
ALBANY...MAKING IT FEEL AUTUMNAL.
HIGH PRESSURE WILL CREST NORTH OF THE REGION EARLY FRIDAY NIGHT
BEFORE RETREATING TO THE CANADIAN MARITIMES. A COOL NIGHT IS IN
STORE BUT NOT AS COOL AS WOULD HAVE BEEN. WHILE THE NIGHT WILL START
CLEAR...CLOUDS SHOULD INCREASE DUE TO WARM AIR ADVECTION AS A POTENT
DISTURBANCE APPROACHES FROM THE OHIO VALLEY. OVERNIGHT LOWS WILL
RANGE FROM THE UPPER 40S SOUTHEAST OF ALBANY...DOWN TO THE UPPER 30S
ACROSS THE ADIRONDACKS. IF IT WERE TO GET ANY COLDER THERE...SOME
FROST WOULD BE POSSIBLE. WE WILL MONITOR THAT POTENTIAL BUT FOR
NOW...WE ARE FORECASTING TEMPERATURES TO REMAIN JUST ABOVE THE FROST
THRESHOLD.
THEN ON SATURDAY...AS THE AFOREMENTIONED DISTURBANCE APPROACH...IT
LOOKS AS OF SURFACE LOW PRESSURE WILL FORM AT THE TRIPLE POINT OF
THE WARM FRONT/COLD FRONT INTERFACE TO OUR SOUTHEAST. AT THIS POINT
SHOWERS APPEARS TO BE A GOOD BET. IF SURFACE LOW PRESSURE DEVELOPS
EVEN QUICKER...WE WOULD BE LOOKING AT A STEADY RAIN. FOR NOW...WILL
CALL IT SHOWERS...BUT EITHER WAY...SATURDAY LOOKS LIKE A
CLOUDY...DAMP DAY WITH HIGHS RANGING ONLY FROM THE MID 50S NORTHWEST
TO UPPER 60S SOUTHEAST OF ALBANY.
THE DISTURBANCE LOOKS TO MOVE QUICKLY EAST SATURDAY NIGHT...FOLLOWED
BY PARTIAL CLEAR AND ANOTHER CANADIAN HIGH PRESSURE BRINGING A
RE-NEWED SHOT OF COOL BUT DRY TO CLOSE OUT THE WEEKEND.
&&
.LONG TERM /SUNDAY THROUGH WEDNESDAY/...
THE LONG TERM PORTION OF THE FORECAST WILL FEATURE A BROAD UPPER
TROUGH ACROSS THE EASTERN 2/3RDS OF NOAM. THIS WILL KEEP
TEMPERATURES A BIT BELOW NORMAL ALONG WITH NEAR TO BELOW NORMAL
PRECIPITATION. THE NEXT APPRECIABLE CHANCE FOR WET WEATHER IS LATE
MONDAY NIGHT INTO TUESDAY AS THE NEXT PV ANOMALY IS PROGGED TO TRACK
ACROSS THE GREAT LAKES REGION AND NORTHEAST CONUS. QPF/S FROM THE
GLOBAL MODELS DIFFER AS THE GFS IS THE MOST AGGRESSIVE /LESS QPF/
WITH TRACK OF THIS WAVE. MEANWHILE THE ECMWF CONTINUES TO SUGGEST A
COASTAL WAVE DEVELOPMENT WHICH SLOWS DOWN THE FORWARD PROGRESS AND
KEEPS THE PRECIP LINGER LONGER /AND HIGHER QPF/. THE GGEM IS
FURTHER SOUTH WITH LIGHTER AMOUNTS AS MAIN WAVE MOVES OFF THE
CAROLINA/VIRGINIA COAST. OTHERWISE...SURFACE HIGH PRESSURE WILL BE
THE MAIN FEATURE. THE H850 MEAN TEMPERATURES ARE EXPECTED TO HOVER
INTO THE MIDDLE SINGLE DIGITS WHICH WILL RESULT IN MAINLY 60S FOR
VALLEY LOCATIONS AND OVERNIGHT LOWS INTO THE 40S.
&&
.AVIATION /12Z THURSDAY THROUGH MONDAY/...
SCATTERED TO BROKEN LINE OF SHOWERS WILL MOVE ACROSS THE REGION THIS
MORNING. CIGS UPSTREAM WERE MAINLY MVFR WITH AN OCCASIONAL HIGH
END IFR. WILL MENTION PREDOMINANT MVFR CONDITIONS...ALTHOUGH BRIEF
IFR WILL CIGS WILL BE POSSIBLE THIS MORNING. WINDS TOO HAVE BEEN
A BIT GUSTY FROM THE SOUTHERLY DIRECTION AND HAVE INCREASED
MAGNITUDES IN THIS SET OF TAFS. VIS HAS NOT SHOWN MUCH
RESTRICTIONS AND WE WILL KEEP THE VALUES INTO VFR.
FRONTAL PASSAGE WILL SIGNIFY AN END TO THE SHOWERS AND A WIND SHIFT
TO THE WEST-NORTHWEST BY AFTERNOON. MAGNITUDES WILL REMAIN AROUND
10 KTS WITH AN OCCASIONAL GUST TO NEAR 20 KTS. CIGS WILL BE A
CHALLENGE AS IT WILL BE BORDERLINE BETWEEN MVFR/VFR...ESPECIALLY
FOR THE UPSLOPE CONDITIONS INTO KPSF.
OUTLOOK...
FRIDAY NIGHT: NO OPERATIONAL IMPACT. NO SIG WX.
SATURDAY: MODERATE OPERATIONAL IMPACT. CHANCE OF SHRA.
SATURDAY NIGHT: MODERATE OPERATIONAL IMPACT. CHANCE OF SHRA.
SUNDAY TO MONDAY: NO OPERATIONAL IMPACT. NO SIG WX.
MONDAY NIGHT TO TUESDAY: MODERATE OPERATIONAL IMPACT. CHANCE OF SHRA.
&&
.FIRE WEATHER...
A COLD FRONT WILL CROSS THE REGION THIS AFTERNOON...BRINGING SOME
SHOWERS AND PERHAPS A THUNDERSTORM...MAINLY SOUTH OF ALBANY.
RAINFALL AMOUNTS WITH SHOWERS LOOK TO BE UP TO HALF AN INCH IN OUR
NORTHWESTERN ZONES...AROUND A QUARTER INCH LOCALLY IN THE CAPITAL
REGION...LESS THAN THAT FURTHER SOUTH.
A SOUTH WIND WILL AVERAGE 10 TO 20 MPH TODAY...SHIFTING TO THE
NORTHWEST BEHIND THE COLD FRONT.
RH LEVELS WILL REMAIN ELEVATED THIS AFTERNOON...ONLY DROPPING INTO
THE 60S.
TONIGHT ALL THE SHOWERS WILL MOVE EAST FOLLOWED BY PARTIAL CLEARING.
A NORTHWEST BREEZE MIGHT BE ENOUGH TO MITIGATE THE FORMATION OF MOST
FOG.
FRIDAY WILL BE A DRY DAY WITH TEMPERATURES A BIT BELOW NORMAL. RH
VALUES BY AFTERNOON WILL BE IN THE 35-45 PERCENT RANGE. THE SURFACE
WIND WILL BE NORTH TO NORTHWEST 5-15 MPH.
THE NEXT CHANCE OF SHOWERS WILL BE ON SATURDAY.
&&
.HYDROLOGY...
NO WIDESPREAD HYDRO PROBLEMS ARE EXPECTED THE NEXT FIVE DAYS
ENDING MONDAY.
SHOWERS AND ANY THUNDERSTORMS TODAY WILL PRODUCE ONLY ABOUT HALF AN
INCH OF AVERAGE BASIN RAINFALL IN OUR NORTHERN AREAS...ABOUT A
QUARTER INCH OR LESS ALBANY SOUTHWARD.
THIS RAIN WILL NOT INFLUENCE ANY OF OUR MAIN STEM RIVERS THROUGH OUT
THE REGION.
ANY THUNDERSTORM COULD CONTAIN LOCALLY HEAVY RAINFALL...WITH AMOUNTS
CLOSER TO AN INCH...JUST ENOUGH TO PRODUCE SOME PONDING OF WATER IN
A FEW SPOTS.
DRY WEATHER WILL RETURN TONIGHT AFTER A POSSIBLE LEFTOVER EVENING
SHOWERS. IT WILL BE DRY FRIDAY...BUT THERE IS A CHANCE OF SHOWERS ON
SATURDAY WITH ANOTHER DISTURBANCE. THEN...DRY WEATHER RETURNS SUNDAY
INTO EARLY NEXT WEEK.
FOR DETAILS ON SPECIFIC AREA RIVERS AND LAKES...INCLUDING OBSERVED
AND FORECAST RIVER STAGES AND LAKE ELEVATIONS...PLEASE VISIT THE
ADVANCED HYDROLOGIC PREDICTION SERVICE /AHPS/ GRAPHS ON OUR WEBSITE.
&&
.ALY WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...NONE.
MA...NONE.
VT...NONE.
&&
$$
SYNOPSIS...HWJIV
NEAR TERM...HWJIV
SHORT TERM...HWJIV
LONG TERM...BGM
AVIATION...BGM/JPV
FIRE WEATHER...HWJIV/WASULA
HYDROLOGY...HWJIV/WASULA
AREA FORECAST DISCUSSION
NWS ALBANY NY
635 AM EDT THU SEP 11 2014
.SYNOPSIS...
LOW PRESSURE IN EASTERN CANADA WILL DRIVE A COLD FRONT ACROSS THE
REGION THIS AFTERNOON. AHEAD OF THIS FRONT WILL BE SCATTERED SHOWERS
AND PERHAPS A THUNDERSTORM...MAINLY SOUTH OF ALBANY. BEHIND THIS
FRONT WILL COME THE COOLEST AIR MASS SINCE LATE MAY BY FRIDAY. A
DISTURBANCE MIGHT BRING A ROUND OF SHOWERS ON SATURDAY FOLLOWED BY
MORE COOL DRY WEATHER SUNDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
AS OF 630 AM EDT...SCATTERED MAINLY LIGHT SHOWERS WERE WORKING INTO
MUCH OF THE AREA. THIS BATCH WILL LEAVE BUT OTHERS WILL THROUGHOUT
THE DAY. LOW PRESSURE WAS WORKING THROUGH SOUTHERN ONTARIO DRAGGING
AA COLD FRONT INTO WESTERN NEW YORK.
FOR THIS UPDATE...JUST INCREASED HOURLY POPS A BIT THIS MORNING (DUE
TO THE SCATTERED SHOWERS MOVING QUICKLY EAST). OTHERWISE VERY LITTLE
TO TWEAK OTHER THAN THAT.
THE LATEST RUC13 INDICATED LITTLE OR NO INSTABILITY SO WE KEPT ANY
MENTION OF THUNDER OUT OF THE FORECAST THROUGH EARLY MORNING.
TEMPERATURES WERE QUITE MILD DUE TO AN INCREASE IN CLOUDS...AND A
PERSISTENT SOUTHERLY BREEZE ON THE WARM SIDE OF THE LOW
PRESSURE...HOLDING MAINLY IN THE 60S.
THE AFOREMENTIONED COLD FRONT ASSOCIATED WITH THE LOW PRESSURE WILL
MOVE STEADILY ALONG AND WORK INTO THE SOUTHERN ADIRONDACKS AND THE
MOHAWK VALLEY EARLY THIS AFTERNOON...THE CAPITAL REGION AND
SURROUNDING AREAS LATE AFTERNOON...AND THE MID HUDSON VALLEY AND
NORTHWESTERN CONNECTICUT BY EARLY EVENING.
DUE TO VERY LIMITED INSTABILITY WE ONLY MENTION A SLIGHT CHANCE OF
THUNDERSTORM FROM THE CAPITAL REGION NORTHWARD. FURTHER SOUTH...WITH
A LITTLE MORE INSTABILITY...WE DID MENTION A CHANCE OF
THUNDERSTORMS. IT IS REMOTELY POSSIBLE THAT ANY THUNDERSTORM IN THIS
AREA COULD CONTAIN SOME GUSTY WINDS AS THE OVERALL WIND FIELD (BULK
SHEAR) INCREASES TO ABOUT 35-40KTS. HOWEVER...THE THREAT APPEARED
LOW ENOUGH NOT TO MENTION IN THE GRIDS OR CERTAINLY ENHANCED WORDING
AT THIS TIME.
PWAT VALUES LOOK TO INCREASE TO ABOUT 2 INCHES...BUT THIS LOOKS TO
HAPPEN THIS MORNING. THE H20 WATER VAPOR LOOP ALREADY INDICATED A
MID LEVEL DRY PUNCH QUICKLY WORKING INTO WESTERN NEW YORK STATE.
THIS DRY PUNCH WILL ALLOW PWATS TO DROP QUICKLY THIS
AFTERNOON...EVEN AHEAD OF THE FRONT. THEREFORE THE BEST FORCING
(WHICH IS GOING TO WELL NORTH)...WILL NOT LINE UP WITH THE BEST
PWATS AND PASSAGE OF THE COLD FRONT.
THERE WILL BE PLENTY OF CLOUDS TODAY WITH PERHAPS A FEW BREAKS OF
AFTERNOON SUNSHINE. EVEN SO...TEMPERATURES COULD SPIKE A LITTLE
AHEAD OF THE FRONT. WE EXPECT HIGHS NEAR 80 IN THE MID HUDSON VALLEY
AND LOWER LITCHFIELD COUNTY...UPPER 70S AROUND ALBANY. FURTHER NORTH
AND WEST WHERE THE COLD FRONT WILL BE FIRST TO COME THROUGH...HIGH
TEMPERATURES WILL BE HELD TO BETWEEN THE UPPER 60S TO MID 70S.
A GUSTY SOUTH WIND PREVAIL TODAY 10 TO 20 MPH...SHIFTING TO THE WEST
BY LATE IN THE DAY ONCE THE COLD FRONT MOVES THROUGH.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH SATURDAY NIGHT/...
THE COLD FRONT WILL BE FINISHING ITS SWEEP THROUGH OUR AREA THIS
EVENING TAKING ANY LEFTOVER SHOWERS WITH IT.
THEN...A COOL CANADIAN AIR MASS WILL BE USHERED IN TONIGHT ON
SOMEWHAT GUSTY NORTH OR NORTHWEST WINDS. THE SKY WILL CLEAR AND
TEMPERATURES WILL DIP DOWN TO AROUND 50 FROM ALBANY SOUTH AND EAST.
FURTHER NORTHWEST AND WEST...THEY WILL DIVE INTO THE 40S...AND EVEN
TOUCH THE UPPER 30S ACROSS OUR ADIRONDACKS.
FRIDAY LOOKS TO FEATURE A GOOD DEAL OF SUNSHINE (MIXING WITH FAIR
WEATHER STRATO-CUMULUS) AND TEMPERATURES BELOW NORMAL. H850
TEMPERATURES LOOK TO DROP TO BETWEEN +5C NORTHWEST TO +9C SOUTHEAST
ACROSS OUR REGION. THIS WILL TRANSLATE TO HIGH TEMPERATURES MAINLY
IN THE 60S THROUGH OUR REGION...PERHAPS TOUCHING 70 FROM
POUGHKEEPSIE...BUT ONLY 50S ACROSS THE ELEVATED TERRAIN NORTH OF
ALBANY...MAKING IT FEEL AUTUMNAL.
HIGH PRESSURE WILL CREST NORTH OF THE REGION EARLY FRIDAY NIGHT
BEFORE RETREATING TO THE CANADIAN MARITIMES. A COOL NIGHT IS IN
STORE BUT NOT AS COOL AS WOULD HAVE BEEN. WHILE THE NIGHT WILL START
CLEAR...CLOUDS SHOULD INCREASE DUE TO WARM AIR ADVECTION AS A POTENT
DISTURBANCE APPROACHES FROM THE OHIO VALLEY. OVERNIGHT LOWS WILL
RANGE FROM THE UPPER 40S SOUTHEAST OF ALBANY...DOWN TO THE UPPER 30S
ACROSS THE ADIRONDACKS. IF IT WERE TO GET ANY COLDER THERE...SOME
FROST WOULD BE POSSIBLE. WE WILL MONITOR THAT POTENTIAL BUT FOR
NOW...WE ARE FORECASTING TEMPERATURES TO REMAIN JUST ABOVE THE FROST
THRESHOLD.
THEN ON SATURDAY...AS THE AFOREMENTIONED DISTURBANCE APPROACH...IT
LOOKS AS OF SURFACE LOW PRESSURE WILL FORM AT THE TRIPLE POINT OF
THE WARM FRONT/COLD FRONT INTERFACE TO OUR SOUTHEAST. AT THIS POINT
SHOWERS APPEARS TO BE A GOOD BET. IF SURFACE LOW PRESSURE DEVELOPS
EVEN QUICKER...WE WOULD BE LOOKING AT A STEADY RAIN. FOR NOW...WILL
CALL IT SHOWERS...BUT EITHER WAY...SATURDAY LOOKS LIKE A
CLOUDY...DAMP DAY WITH HIGHS RANGING ONLY FROM THE MID 50S NORTHWEST
TO UPPER 60S SOUTHEAST OF ALBANY.
THE DISTURBANCE LOOKS TO MOVE QUICKLY EAST SATURDAY NIGHT...FOLLOWED
BY PARTIAL CLEAR AND ANOTHER CANADIAN HIGH PRESSURE BRINGING A
RE-NEWED SHOT OF COOL BUT DRY TO CLOSE OUT THE WEEKEND.
&&
.LONG TERM /SUNDAY THROUGH WEDNESDAY/...
THE LONG TERM PORTION OF THE FORECAST WILL FEATURE A BROAD UPPER
TROUGH ACROSS THE EASTERN 2/3RDS OF NOAM. THIS WILL KEEP
TEMPERATURES A BIT BELOW NORMAL ALONG WITH NEAR TO BELOW NORMAL
PRECIPITATION. THE NEXT APPRECIABLE CHANCE FOR WET WEATHER IS LATE
MONDAY NIGHT INTO TUESDAY AS THE NEXT PV ANOMALY IS PROGGED TO TRACK
ACROSS THE GREAT LAKES REGION AND NORTHEAST CONUS. QPF/S FROM THE
GLOBAL MODELS DIFFER AS THE GFS IS THE MOST AGGRESSIVE /LESS QPF/
WITH TRACK OF THIS WAVE. MEANWHILE THE ECMWF CONTINUES TO SUGGEST A
COASTAL WAVE DEVELOPMENT WHICH SLOWS DOWN THE FORWARD PROGRESS AND
KEEPS THE PRECIP LINGER LONGER /AND HIGHER QPF/. THE GGEM IS
FURTHER SOUTH WITH LIGHTER AMOUNTS AS MAIN WAVE MOVES OFF THE
CAROLINA/VIRGINIA COAST. OTHERWISE...SURFACE HIGH PRESSURE WILL BE
THE MAIN FEATURE. THE H850 MEAN TEMPERATURES ARE EXPECTED TO HOVER
INTO THE MIDDLE SINGLE DIGITS WHICH WILL RESULT IN MAINLY 60S FOR
VALLEY LOCATIONS AND OVERNIGHT LOWS INTO THE 40S.
&&
.AVIATION /12Z THURSDAY THROUGH MONDAY/...
CLOUDS CONTINUE TO INCREASE...THICKEN AND LOWER ACROSS THE REGION
WITH LATEST VIEW OF THE 11U-3.9U SATELLITE IMAGERY REVEALING THE
EXPANDING LOW LEVEL STRATUS /MVFR CIGS/ FROM THE WEST-SOUTHWEST
DIRECTION ADVECTING NORTHWARD. WE WILL THEREFORE PLACE AT LEAST
MVFR FLIGHT RESTRICTIONS INTO THE TAF/S OVERNIGHT. AS FOR SHOWER
POTENTIAL...UPSTREAM REGIONAL RADAR MOSAIC SHOWS THE LEADING EDGE OF
THE PRECIP IS ERODING DUE TO THE DOWNSTREAM DRY AIRMASS IN PLACE.
PER THE LATEST HRRR REFLECTIVITY...EXPECTATIONS ARE FOR THE SHOWER
POTENTIAL TO INCREASE TOWARD SUNRISE AS THESE THOUGHTS ARE REFLECTED
IN THE TAF/S.
THE BEST TIME PERIOD FOR WET WEATHER APPEARS TO BE AROUND SUNRISE
AND INTO THE MID MORNING HOURS ASSOCIATED WITH THE FRONTAL PASSAGE.
AFTER FROPA...WINDS WILL SHIFT TOWARD THE WEST-NORTHWEST WITH A
DRIER MID LEVELS. HOWEVER...LOWER LEVEL MOISTURE MAY LINGER AS WE
WILL KEEP CIGS ON THE BORDER OF MVFR/VFR.
WINDS WILL BE SOUTHERLY TO SOUTHEASTERLY AROUND 3-7
KT...BECOMING SOUTH AND INCREASING TO 5-10 KT BY 12Z THURSDAY. WINDS
WILL SHIFT TO THE WEST-NORTHWEST AROUND 10KTS WITH SOME HIGHER GUSTS
TOWARD 20KTS POSSIBLE BY AFTERNOON.
OUTLOOK...
THURSDAY NIGHT: MODERATE OPERATIONAL IMPACT. CHANCE OF SHRA.
FRIDAY: NO OPERATIONAL IMPACT. NO SIG WX.
FRIDAY NIGHT: NO OPERATIONAL IMPACT. NO SIG WX.
SATURDAY: MODERATE OPERATIONAL IMPACT. SCATTERED SHRA.
SATURDAY NIGHT: MODERATE OPERATIONAL IMPACT. CHANCE OF SHRA.
SUNDAY TO MONDAY: NO OPERATIONAL IMPACT. NO SIG WX.
&&
.FIRE WEATHER...
A COLD FRONT WILL CROSS THE REGION THIS AFTERNOON...BRINGING SOME
SHOWERS AND PERHAPS A THUNDERSTORM...MAINLY SOUTH OF ALBANY.
RAINFALL AMOUNTS WITH SHOWERS LOOK TO BE UP TO HALF AN INCH IN OUR
NORTHWESTERN ZONES...AROUND A QUARTER INCH LOCALLY IN THE CAPITAL
REGION...LESS THAN THAT FURTHER SOUTH.
A SOUTH WIND WILL AVERAGE 10 TO 20 MPH TODAY...SHIFTING TO THE
NORTHWEST BEHIND THE COLD FRONT.
RH LEVELS WILL REMAIN ELEVATED THIS AFTERNOON...ONLY DROPPING INTO
THE 60S.
TONIGHT ALL THE SHOWERS WILL MOVE EAST FOLLOWED BY PARTIAL CLEARING.
A NORTHWEST BREEZE MIGHT BE ENOUGH TO MITIGATE THE FORMATION OF MOST
FOG.
FRIDAY WILL BE A DRY DAY WITH TEMPERATURES A BIT BELOW NORMAL. RH
VALUES BY AFTERNOON WILL BE IN THE 35-45 PERCENT RANGE. THE SURFACE
WIND WILL BE NORTH TO NORTHWEST 5-15 MPH.
THE NEXT CHANCE OF SHOWERS WILL BE ON SATURDAY.
&&
.HYDROLOGY...
NO WIDESPREAD HYDRO PROBLEMS ARE EXPECTED THE NEXT FIVE DAYS
ENDING MONDAY.
SHOWERS AND ANY THUNDERSTORMS TODAY WILL PRODUCE ONLY ABOUT HALF AN
INCH OF AVERAGE BASIN RAINFALL IN OUR NORTHERN AREAS...ABOUT A
QUARTER INCH OR LESS ALBANY SOUTHWARD.
THIS RAIN WILL NOT INFLUENCE ANY OF OUR MAIN STEM RIVERS THROUGH OUT
THE REGION.
ANY THUNDERSTORM COULD CONTAIN LOCALLY HEAVY RAINFALL...WITH AMOUNTS
CLOSER TO AN INCH...JUST ENOUGH TO PRODUCE SOME PONDING OF WATER IN
A FEW SPOTS.
DRY WEATHER WILL RETURN TONIGHT AFTER A POSSIBLE LEFTOVER EVENING
SHOWERS. IT WILL BE DRY FRIDAY...BUT THERE IS A CHANCE OF SHOWERS ON
SATURDAY WITH ANOTHER DISTURBANCE. THEN...DRY WEATHER RETURNS SUNDAY
INTO EARLY NEXT WEEK.
FOR DETAILS ON SPECIFIC AREA RIVERS AND LAKES...INCLUDING OBSERVED
AND FORECAST RIVER STAGES AND LAKE ELEVATIONS...PLEASE VISIT THE
ADVANCED HYDROLOGIC PREDICTION SERVICE /AHPS/ GRAPHS ON OUR WEBSITE.
&&
.ALY WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...NONE.
MA...NONE.
VT...NONE.
&&
$$
SYNOPSIS...HWJIV
NEAR TERM...HWJIV
SHORT TERM...HWJIV
LONG TERM...BGM
AVIATION...BGM
FIRE WEATHER...HWJIV/WASULA
HYDROLOGY...HWJIV/WASULA
AREA FORECAST DISCUSSION
NWS ALBANY NY
445 AM EDT THU SEP 11 2014
.SYNOPSIS...
LOW PRESSURE IN EASTERN CANADA WILL DRIVE A COLD FRONT ACROSS THE
REGION LATER TODAY. AHEAD OF THIS FRONT WILL BE SCATTERED SHOWERS
AND PERHAPS A THUNDERSTORM...MAINLY SOUTH OF ALBANY. BEHIND THIS
FRONT WILL COME THE COOLEST AIR MASS SINCE LATE MAY BY FRIDAY. A
DISTURBANCE MIGHT BRING A ROUND OF SHOWERS ON SATURDAY FOLLOWED BY
MORE COOL DRY WEATHER SUNDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
AS OF 445 AM EDT...A RATHER POTENT LOW PRESSURE AREA WAS JUST NORTH
OF LAKE HURON. THIS STORM HAS A WINTRY LOOK TO IT IN THAT IT HAS A
VERY WELL DEFINED AREA OF DEFORMATION RAIN ON ITS NORTHWEST SIDE...A
COLD RAIN AT THAT...WITH POSSIBLY A LITTLE WET SNOW MIXING TO THE
SOUTH OF JAMES IN CANADA.
CLOSER TO HOME...RAIN SHOWERS WERE WORKING INTO OUR WESTERN AREAS TO
THE WEST OF THE HUDSON RIVER VALLEY. SO FAR THERE HAS BEEN NO
INDICATIONS OF THUNDERSTORMS WITH THIS FIRST LINE OF SHOWERS. THE
LATEST RUC13 INDICATE LITTLE OR NO INSTABILITY SO WE KEPT ANY
MENTION OF THUNDER OUT OF THE FORECAST THROUGH EARLY MORNING.
TEMPERATURES WERE QUITE MILD DUE TO AN INCREASE IN CLOUDS...AND A
PERSISTENT SOUTHERLY BREEZE ON THE WARM SIDE OF THE LOW
PRESSURE...HOLDING MAINLY IN THE 60S.
A COLD FRONT ASSOCIATED WITH THE LOW PRESSURE WAS WORKING INTO
WESTERN NY STATE. THIS FRONT WILL MOVE STEADILY ALONG AND WORK INTO
THE SOUTHERN ADIRONDACKS AND THE MOHAWK VALLEY EARLY THIS
AFTERNOON...THE CAPITAL REGION AND SURROUNDING AREAS LATE
AFTERNOON...AND THE MID HUDSON VALLEY AND NORTHWESTERN CONNECTICUT
BY EARLY EVENING.
MORE LINES OF SHOWERS CAN BE EXPECTED TODAY. DUE TO VERY LIMITED
INSTABILITY WE ONLY MENTION A SLIGHT CHANCE OF THUNDERSTORM FROM THE
CAPITAL REGION NORTHWARD. FURTHER SOUTH...WITH A LITTLE MORE
INSTABILITY...WE DID MENTION A CHANCE OF THUNDERSTORMS. IT IS
REMOTELY POSSIBLE THAT ANY THUNDERSTORM IN THIS AREA COULD CONTAIN
SOME GUSTY WINDS AS THE OVERALL WIND FIELD (BULK SHEAR) INCREASES TO
ABOUT 35-40KTS. HOWEVER...THE THREAT APPEARED LOW ENOUGH NOT TO
MENTION IN THE GRIDS OR CERTAINLY ENHANCED WORDING AT THIS TIME.
PWAT VALUES LOOK TO INCREASE TO ABOUT 2 INCHES...BUT THIS LOOKS TO
HAPPEN THIS MORNING. THE H20 WATER VAPOR LOOP ALREADY INDICATED A
MID LEVEL DRY PUNCH QUICKLY WORKING INTO WESTERN NEW YORK STATE.
THIS DRY PUNCH WILL ALLOW PWATS TO DROP QUICKLY THIS
AFTERNOON...EVEN AHEAD OF THE FRONT. THEREFORE THE BEST FORCING
(WHICH IS GOING TO WELL NORTH)...WILL NOT LINE UP WITH THE BEST
PWATS AND PASSAGE OF THE COLD FRONT.
THERE WILL BE PLENTY OF CLOUDS TODAY WITH PERHAPS A FEW BREAKS OF
AFTERNOON SUNSHINE. EVEN SO...TEMPERATURES COULD SPIKE A LITTLE
AHEAD OF THE FRONT...AS THEY WERE ACTUALLY IN THE LOWER 70S IN
SECTIONS OF CENTRAL NEW YORK! WE EXPECT HIGHS NEAR 80 IN THE MID
HUDSON VALLEY AND LOWER LITCHFIELD COUNTY...UPPER 70S AROUND ALBANY.
FURTHER NORTH AND WEST WHERE THE COLD FRONT WILL BE FIRST TO COME
THROUGH...HIGH TEMPERATURES WILL BE HELD TO BETWEEN THE UPPER 60S TO
MID 70S.
A GUSTY SOUTH WIND PREVAIL TODAY 10 TO 20 MPH...SHIFTING TO THE WEST
BY LATE IN THE DAY ONCE THE COLD FRONT MOVES THROUGH.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH SATURDAY NIGHT/...
THE COLD FRONT WILL BE FINISHING ITS SWEEP THROUGH OUR AREA THIS
EVENING TAKING ANY LEFTOVER SHOWERS WITH IT.
THEN...A COOL CANADIAN AIR MASS WILL BE USHERED IN TONIGHT ON
SOMEWHAT GUSTY NORTH OR NORTHWEST WINDS. THE SKY WILL CLEAR AND
TEMPERATURES WILL DIP DOWN TO AROUND 50 FROM ALBANY SOUTH AND EAST.
FURTHER NORTHWEST AND WEST...THEY WILL DIVE INTO THE 40S...AND EVEN
TOUCH THE UPPER 30S ACROSS OUR ADIRONDACKS.
FRIDAY LOOKS TO FEATURE A GOOD DEAL OF SUNSHINE (MIXING WITH FAIR
WEATHER STRATO-CUMULUS) AND TEMPERATURES BELOW NORMAL. H850
TEMPERATURES LOOK TO DROP TO BETWEEN +5C NORTHWEST TO +9C SOUTHEAST
ACROSS OUR REGION. THIS WILL TRANSLATE TO HIGH TEMPERATURES MAINLY
IN THE 60S THROUGH OUR REGION...PERHAPS TOUCHING 70 FROM
POUGHKEEPSIE...BUT ONLY 50S ACROSS THE ELEVATED TERRAIN NORTH OF
ALBANY...MAKING IT FEEL AUTUMNAL.
HIGH PRESSURE WILL CREST NORTH OF THE REGION EARLY FRIDAY NIGHT
BEFORE RETREATING TO THE CANADIAN MARITIMES. A COOL NIGHT IS IN
STORE BUT NOT AS COOL AS WOULD HAVE BEEN. WHILE THE NIGHT WILL START
CLEAR...CLOUDS SHOULD INCREASE DUE TO WARM AIR ADVECTION AS A POTENT
DISTURBANCE APPROACHES FROM THE OHIO VALLEY. OVERNIGHT LOWS WILL
RANGE FROM THE UPPER 40S SOUTHEAST OF ALBANY...DOWN TO THE UPPER 30S
ACROSS THE ADIRONDACKS. IF IT WERE TO GET ANY COLDER THERE...SOME
FROST WOULD BE POSSIBLE. WE WILL MONITOR THAT POTENTIAL BUT FOR
NOW...WE ARE FORECASTING TEMPERATURES TO REMAIN JUST ABOVE THE FROST
THRESHOLD.
THEN ON SATURDAY...AS THE AFOREMENTIONED DISTURBANCE APPROACH...IT
LOOKS AS OF SURFACE LOW PRESSURE WILL FORM AT THE TRIPLE POINT OF
THE WARM FRONT/COLD FRONT INTERFACE TO OUR SOUTHEAST. AT THIS POINT
SHOWERS APPEARS TO BE A GOOD BET. IF SURFACE LOW PRESSURE DEVELOPS
EVEN QUICKER...WE WOULD BE LOOKING AT A STEADY RAIN. FOR NOW...WILL
CALL IT SHOWERS...BUT EITHER WAY...SATURDAY LOOKS LIKE A
CLOUDY...DAMP DAY WITH HIGHS RANGING ONLY FROM THE MID 50S NORTHWEST
TO UPPER 60S SOUTHEAST OF ALBANY.
THE DISTURBANCE LOOKS TO MOVE QUICKLY EAST SATURDAY NIGHT...FOLLOWED
BY PARTIAL CLEAR AND ANOTHER CANADIAN HIGH PRESSURE BRINGING A
RE-NEWED SHOT OF COOL BUT DRY TO CLOSE OUT THE WEEKEND.
&&
.LONG TERM /SUNDAY THROUGH WEDNESDAY/...
THE LONG TERM PORTION OF THE FORECAST WILL FEATURE A BROAD UPPER
TROUGH ACROSS THE EASTERN 2/3RDS OF NOAM. THIS WILL KEEP
TEMPERATURES A BIT BELOW NORMAL ALONG WITH NEAR TO BELOW NORMAL
PRECIPITATION. THE NEXT APPRECIABLE CHANCE FOR WET WEATHER IS LATE
MONDAY NIGHT INTO TUESDAY AS THE NEXT PV ANOMALY IS PROGGED TO TRACK
ACROSS THE GREAT LAKES REGION AND NORTHEAST CONUS. QPF/S FROM THE
GLOBAL MODELS DIFFER AS THE GFS IS THE MOST AGGRESSIVE /LESS QPF/
WITH TRACK OF THIS WAVE. MEANWHILE THE ECMWF CONTINUES TO SUGGEST A
COASTAL WAVE DEVELOPMENT WHICH SLOWS DOWN THE FORWARD PROGRESS AND
KEEPS THE PRECIP LINGER LONGER /AND HIGHER QPF/. THE GGEM IS
FURTHER SOUTH WITH LIGHTER AMOUNTS AS MAIN WAVE MOVES OFF THE
CAROLINA/VIRGINIA COAST. OTHERWISE...SURFACE HIGH PRESSURE WILL BE
THE MAIN FEATURE. THE H850 MEAN TEMPERATURES ARE EXPECTED TO HOVER
INTO THE MIDDLE SINGLE DIGITS WHICH WILL RESULT IN MAINLY 60S FOR
VALLEY LOCATIONS AND OVERNIGHT LOWS INTO THE 40S.
&&
.AVIATION /08Z THURSDAY THROUGH MONDAY/...
CLOUDS CONTINUE TO INCREASE...THICKEN AND LOWER ACROSS THE REGION
WITH LATEST VIEW OF THE 11U-3.9U SATELLITE IMAGERY REVEALING THE
EXPANDING LOW LEVEL STRATUS /MVFR CIGS/ FROM THE WEST-SOUTHWEST
DIRECTION ADVECTING NORTHWARD. WE WILL THEREFORE PLACE AT LEAST
MVFR FLIGHT RESTRICTIONS INTO THE TAF/S OVERNIGHT. AS FOR SHOWER
POTENTIAL...UPSTREAM REGIONAL RADAR MOSAIC SHOWS THE LEADING EDGE OF
THE PRECIP IS ERODING DUE TO THE DOWNSTREAM DRY AIRMASS IN PLACE.
PER THE LATEST HRRR REFLECTIVITY...EXPECTATIONS ARE FOR THE SHOWER
POTENTIAL TO INCREASE TOWARD SUNRISE AS THESE THOUGHTS ARE REFLECTED
IN THE TAF/S.
THE BEST TIME PERIOD FOR WET WEATHER APPEARS TO BE AROUND SUNRISE
AND INTO THE MID MORNING HOURS ASSOCIATED WITH THE FRONTAL PASSAGE.
AFTER FROPA...WINDS WILL SHIFT TOWARD THE WEST-NORTHWEST WITH A
DRIER MID LEVELS. HOWEVER...LOWER LEVEL MOISTURE MAY LINGER AS WE
WILL KEEP CIGS ON THE BORDER OF MVFR/VFR.
WINDS WILL BE SOUTHERLY TO SOUTHEASTERLY AROUND 3-7
KT...BECOMING SOUTH AND INCREASING TO 5-10 KT BY 12Z THURSDAY. WINDS
WILL SHIFT TO THE WEST-NORTHWEST AROUND 10KTS WITH SOME HIGHER GUSTS
TOWARD 20KTS POSSIBLE BY AFTERNOON.
OUTLOOK...
THURSDAY NIGHT: MODERATE OPERATIONAL IMPACT. CHANCE OF SHRA.
FRIDAY: NO OPERATIONAL IMPACT. NO SIG WX.
FRIDAY NIGHT: NO OPERATIONAL IMPACT. NO SIG WX.
SATURDAY: MODERATE OPERATIONAL IMPACT. SCATTERED SHRA.
SATURDAY NIGHT: MODERATE OPERATIONAL IMPACT. CHANCE OF SHRA.
SUNDAY TO MONDAY: NO OPERATIONAL IMPACT. NO SIG WX.
&&
.FIRE WEATHER...
A COLD FRONT WILL CROSS THE REGION THIS AFTERNOON...BRINGING SOME
SHOWERS AND PERHAPS A THUNDERSTORM...MAINLY SOUTH OF ALBANY.
RAINFALL AMOUNTS WITH SHOWERS LOOK TO BE UP TO HALF AN INCH IN OUR
NORTHWESTERN ZONES...AROUND A QUARTER INCH LOCALLY IN THE CAPITAL
REGION...LESS THAN THAT FURTHER SOUTH.
A SOUTH WIND WILL AVERAGE 10 TO 20 MPH TODAY...SHIFTING TO THE
NORTHWEST BEHIND THE COLD FRONT.
RH LEVELS WILL REMAIN ELEVATED THIS AFTERNOON...ONLY DROPPING INTO
THE 60S.
TONIGHT ALL THE SHOWERS WILL MOVE EAST FOLLOWED BY PARTIAL CLEARING.
A NORTHWEST BREEZE MIGHT BE ENOUGH TO MITIGATE THE FORMATION OF MOST
FOG.
FRIDAY WILL BE A DRY DAY WITH TEMPERATURES A BIT BELOW NORMAL. RH
VALUES BY AFTERNOON WILL BE IN THE 35-45 PERCENT RANGE. THE SURFACE
WIND WILL BE NORTH TO NORTHWEST 5-15 MPH.
THE NEXT CHANCE OF SHOWERS WILL BE ON SATURDAY.
&&
.HYDROLOGY...
NO WIDESPREAD HYDRO PROBLEMS ARE EXPECTED THE NEXT FIVE DAYS
ENDING MONDAY.
SHOWERS AND ANY THUNDERSTORMS TODAY WILL PRODUCE ONLY ABOUT HALF AN
INCH OF AVERAGE BASIN RAINFALL IN OUR NORTHERN AREAS...ABOUT A
QUARTER INCH OR LESS ALBANY SOUTHWARD.
THIS RAIN WILL NOT INFLUENCE ANY OF OUR MAIN STEM RIVERS THROUGH OUT
THE REGION.
ANY THUNDERSTORM COULD CONTAIN LOCALLY HEAVY RAINFALL...WITH AMOUNTS
CLOSER TO AN INCH...JUST ENOUGH TO PRODUCE SOME PONDING OF WATER IN
A FEW SPOTS.
DRY WEATHER WILL RETURN TONIGHT AFTER A POSSIBLE LEFTOVER EVENING
SHOWERS. IT WILL BE DRY FRIDAY...BUT THERE IS A CHANCE OF SHOWERS ON
SATURDAY WITH ANOTHER DISTURBANCE. THEN...DRY WEATHER RETURNS SUNDAY
INTO EARLY NEXT WEEK.
FOR DETAILS ON SPECIFIC AREA RIVERS AND LAKES...INCLUDING OBSERVED
AND FORECAST RIVER STAGES AND LAKE ELEVATIONS...PLEASE VISIT THE
ADVANCED HYDROLOGIC PREDICTION SERVICE /AHPS/ GRAPHS ON OUR WEBSITE.
&&
.ALY WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...NONE.
MA...NONE.
VT...NONE.
&&
$$
SYNOPSIS...HWJIV
NEAR TERM...HWJIV
SHORT TERM...HWJIV
LONG TERM...BGM
AVIATION...BGM
FIRE WEATHER...HWJIV/WASULA
HYDROLOGY...HWJIV/WASULA
AREA FORECAST DISCUSSION
NWS ALBANY NY
130 AM EDT THU SEP 11 2014
.SYNOPSIS...
LOW PRESSURE WILL MOVE INTO SOUTHEASTERN CANADA
OVERNIGHT...AS A COLD FRONT APPROACHES THE REGION. THIS COLD FRONT
WILL BRING SHOWERS AND ISOLATED THUNDERSTORMS TO SOME LOCATIONS
THIS MORNING INTO THE AFTERNOON. HIGH PRESSURE WILL BRING COOL
AND DRY WEATHER BACK INTO THE REGION THURSDAY NIGHT INTO EARLY
SATURDAY.
&&
.NEAR TERM /UNTIL 6 AM THIS MORNING/...
AS OF 100 AM EDT...CLOUDS CONTINUE TO SLOWLY GATHER OVER MOST OF THE
REGION...WHILE STILL THIN AND ONLY PARTIAL IN SOUTHERN AREAS. RADARS
INDICATED A FEW POSSIBLE SPRINKLES OVER NORTHERN AREAS...WHILE THE
MORE SIGNIFICANT MEASURABLE SHOWERS HAVE YET TO WORK INTO OUR
NORTHWESTERN AREAS.
FOR THIS UPDATE...ONLY SLIGHT MODIFICATION OF THE HOURLY POPS AS
MOST OF THE NEWEST GUIDANCE INDICATED SHOWERS WILL BE WORKING INTO
THE CAPITAL REGION BY SUNRISE...TO INCREASED POPS A LITTLE.
OTHERWISE ONLY VERY MINOR TINKERING OF THE REMAINDER OF THE HOURLY
GRIDS.
TEMPERATURES WILL BE MILDER THAN THE PREVIOUS FEW NIGHTS DUE TO
THE LOW LEVEL WARM ADVECTION...LIGHT SOUTHERLY BREEZE...AND
INCREASING CLOUDS. LOWS WILL GENERALLY BE IN THE MID AND U50S OVER
THE MTNS...AND U50S TO L60S IN THE VALLEYS.
&&
.SHORT TERM /6 AM THIS MORNING THROUGH SATURDAY/...TOMORROW...THE
TIMING/SPEED OF THE COLD FRONT HAS INCREASED ACCORDING TO THE LATEST
NAM/CAN GGEM/ECMWF/GFS FOR AN EARLIER ONSET OF THE SHOWERS AND ISOLD
THUNDERSTORMS SOUTH AND EAST OF THE CAPITAL REGION. THE THREAT FOR
THUNDERSTORMS HAVE GREATLY DIMINISHED NORTH AND WEST OF THE CAPITAL
REGION DUE TO LIMITED HEATING AHEAD OF THE FRONT...AND HENCE A LACK
OF INSTABILITY. THE BEST L0W-LEVEL CONVERGENCE IS WITH THE
FRONT...AND S/SW LLJ AT H850 INCREASES TO 40-50 KTS OR SO AROUND
12Z...AND CONTINUES AT 30-45 KTS IN THE AFTERNOON. POPS WERE
INCREASED TO LIKELY VALUES IN THE LATE MORNING INTO THE
AFTERNOON...ESPECIALLY FROM THE
BERKSHIRES...CAPITAL REGION...AND NRN CATSKILLS...NORTH AND WEST.
SOME OROGRAPHIC ENHANCEMENT IS POSSIBLE OVER THE SRN GREENS...AND
WRN DACKS...AS THE BOUNDARY LAYER WINDS VEER TO THE WEST BY
LUNCHTIME. MUCH OF THE HYDRO SERVICE AREA NEEDS SOME RAINFALL. THE
CONVERGENCE WEAKENS A BIT SOUTH OF THE CAPITAL REGION...BUT AN
ISOLD THUNDERSTORMS ARE POSSIBLE WITH SBCAPE VALUES OF 200-500 J/KG.
A THREAT WAS CONTINUED THERE INTO THE EARLY EVENING. PWATS BRIEFLY
SURGE TO 1.5-2.0" OR SO AHEAD OF THE FRONT...BUT THIS IS FOR A
SHORT DURATION...SO LOCALLY HEAVY RAINFALL WAS REMOVED FROM THE
GRIDS AT THIS TIME. HIGHS WILL GENERALLY BE IN THE U70S TO L80S
FROM THE CAPITAL REGION...AND MOHAWK VALLEY SOUTH AND EAST...AND
U60S T0 L70S NORTH AND WEST...EXCEPT MID OR UPPER 70S IN THE UPPER
HUDSON VALLEY...AND PARTS OF THE CT RIVER VALLEY.
THU NIGHT...THE FRONT SLIDES SOUTH AND EAST OF THE FCST AREA WITH
THE ISOLD-SCT SHOWERS ENDING IN THE EARLY EVENING. STRONG LOW-
LEVEL COLD ADVECTION OCCURS IN THE WAKE OF THE FRONT. H850 TEMPS
FALL TO -4C TO -10C FROM ALY NORTH AND WEST...AND -10C TO -14C TO
THE SOUTH AND EAST. THE SKIES WILL GRADUALLY CLEAR FROM NW TO
SE...AND A N TO NW BREEZE OF 5-15 MPH WILL KEEP IT COOL. LOWS WILL
BE IN THE U40S TO L50S SOUTH AND EAST OF THE CAPITAL DISTRICT /FEW
MD 50S IN NW CT AND THE MID HUDSON VALLEY/...AND LOWER TO MID 40S
NORTH AND WEST...AND EVEN A FEW U30S OVER THE SRN DACKS.
FRI-FRI NIGHT...FAIR...COOL AND DRY WEATHER RETURNS TO THE FCST
AREA...AS A LARGE DOME OF CANADIAN HIGH PRESSURE RIDGES IN FROM
S-CNTRL CANADA...THE NRN PLAINS...AND GREAT LAKES REGION. MAX
TEMPS WILL RUN ABOUT 5-10 DEGREES BELOW NORMAL WITH HIGHS MAINLY
IN THE 60S. SOME U50S ARE POSSIBLE OVER THE SRN GREENS...SRN
DACKS...AND ERN CATSKILLS. A FEW L70S ARE POSSIBLE OVER THE MID
HUDSON VALLEY. A COOL NIGHT IS EXPECTED WITH PERHAPS SOME PATCHY
FROST OVER THE SRN DACKS WITH TEMPS IN THE MID AND U30S. EXPECT
LOWER TO M40S OVER A LARGE PORTION OF THE REST OF THE AREA. THE
METMOS MINS WERE FAVORED HERE.
SATURDAY...A SHORT-WAVE TROUGH...AND A WEAK COLD FRONT MAY
INCREASE THE CLOUDS WITH A CHC OF SHOWERS IN THE AFTERNOON. TEMPS
WILL BE A LITTLE MILDER THAN FRI WITH HIGHS IN THE 60S TO L70S.
THE GFS AND ECMWF/CAN GGEM CONTINUE TO DISAGREE ON THE AMOUNT OF
MOISTURE ASSOCIATED WITH THE SHORT-WAVE...WITH THE INTERNATIONAL
GUIDANCE WETTER THAN THE GFS.
&&
.LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/...
THE LONG TERM PERIOD WILL BE CHARACTERIZED BY MAINLY DRY CONDITIONS
AND HIGH PRESSURE EXCEPT FOR TWO WEAK DISTURBANCES PRODUCING
SCATTERED SHOWERS ACROSS THE REGION SATURDAY NIGHT AND MONDAY NIGHT
INTO TUESDAY.
AT THE START OF THE LONG TERM PERIOD...A WEAK UPPER-LEVEL SHORTWAVE
TROUGH WILL BE PROGRESSING ACROSS THE REGION SATURDAY NIGHT WITH
LINGERING SHOWERS SATURDAY NIGHT ACROSS THE REGION. THESE SHOWERS
ARE EXPECTED TO CLEAR THE REGION BY DAYBREAK SUNDAY AS HIGH PRESSURE
BUILDS ACROSS THE REGION FOR THE REMAINDER OF THE WEEKEND WITH
PARTLY CLOUDY SKIES AND DRY WEATHER.
THIS AREA OF HIGH PRESSURE WILL MOVE ACROSS THE REGION MONDAY AS
ANOTHER WEAK SHORTWAVE TROUGH/CLIPPER-TYPE SYSTEM APPROACHES FROM
THE GREAT LAKES REGION MONDAY NIGHT. MOISTURE LOOKS TO BE LIMITED
WITH THIS FEATURE BUT ENOUGH FORCING SHOULD BE PRESENT TO PROMOTE
ISOLATED TO SCATTERED SHOWERS ACROSS THE REGION MONDAY NIGHT INTO
TUESDAY. HIGH PRESSURE WILL BUILD ACROSS THE REGION THROUGH THE
REMAINDER OF THE LONG TERM PERIOD WITH DRY CONDITIONS AND PARTLY
CLOUDY SKIES.
HIGH TEMPERATURES THROUGHOUT THE LONG TERM PERIOD WILL GENERALLY
RANGE FROM THE UPPER 50S ACROSS THE HIGHER TERRAIN TO NEAR 70 IN
VALLEY LOCATIONS. LOW TEMPERATURES WILL GENERALLY RANGE FROM THE LOW
40S TO NEAR 50...WITH UPPER 30S POSSIBLE ACROSS THE SOUTHERN
ADIRONDACKS SUNDAY NIGHT.
&&
.AVIATION /06Z THURSDAY THROUGH MONDAY/...
CLOUDS CONTINUE TO INCREASE...THICKEN AND LOWER ACROSS THE REGION
WITH LATEST VIEW OF THE 11U-3.9U SATELLITE IMAGERY REVEALING THE
EXPANDING LOW LEVEL STRATUS /MVFR CIGS/ FROM THE WEST-SOUTHWEST
DIRECTION ADVECTING NORTHWARD. WE WILL THEREFORE PLACE AT LEAST
MVFR FLIGHT RESTRICTIONS INTO THE TAF/S OVERNIGHT. AS FOR SHOWER
POTENTIAL...UPSTREAM REGIONAL RADAR MOSAIC SHOWS THE LEADING EDGE OF
THE PRECIP IS ERODING DUE TO THE DOWNSTREAM DRY AIRMASS IN PLACE.
PER THE LATEST HRRR REFLECTIVITY...EXPECTATIONS ARE FOR THE SHOWER
POTENTIAL TO INCREASE TOWARD SUNRISE AS THESE THOUGHTS ARE REFLECTED
IN THE TAF/S.
THE BEST TIME PERIOD FOR WET WEATHER APPEARS TO BE AROUND SUNRISE
AND INTO THE MID MORNING HOURS ASSOCIATED WITH THE FRONTAL PASSAGE.
AFTER FROPA...WINDS WILL SHIFT TOWARD THE WEST-NORTHWEST WITH A
DRIER MID LEVELS. HOWEVER...LOWER LEVEL MOISTURE MAY LINGER AS WE
WILL KEEP CIGS ON THE BORDER OF MVFR/VFR.
WINDS WILL BE SOUTHERLY TO SOUTHEASTERLY AROUND 3-7
KT...BECOMING SOUTH AND INCREASING TO 5-10 KT BY 12Z THURSDAY. WINDS
WILL SHIFT TO THE WEST-NORTHWEST AROUND 10KTS WITH SOME HIGHER GUSTS
TOWARD 20KTS POSSIBLE BY AFTERNOON.
OUTLOOK...
THURSDAY NIGHT: MODERATE OPERATIONAL IMPACT. CHANCE OF SHRA.
FRIDAY: NO OPERATIONAL IMPACT. NO SIG WX.
FRIDAY NIGHT: NO OPERATIONAL IMPACT. NO SIG WX.
SATURDAY: MODERATE OPERATIONAL IMPACT. SCATTERED SHRA.
SATURDAY NIGHT: MODERATE OPERATIONAL IMPACT. CHANCE OF SHRA.
SUNDAY TO MONDAY: NO OPERATIONAL IMPACT. NO SIG WX.
&&
.FIRE WEATHER...
LOW PRESSURE WILL MOVE INTO SOUTHEASTERN CANADA
TONIGHT...AS A COLD FRONT APPROACHES THE REGION. THIS COLD FRONT
WILL BRING SHOWERS AND ISOLATED THUNDERSTORMS TO SOME LOCATIONS
TOMORROW MORNING INTO THE AFTERNOON. HIGH PRESSURE WILL BRING COOL
AND DRY WEATHER BACK INTO THE REGION THURSDAY NIGHT INTO EARLY
SATURDAY.
THE RH VALUES WILL INCREASE TO 90 TO 100 PERCENT TONIGHT...THEN
LOWER TO 50 TO 70 PERCENT TOMORROW AFTERNOON IN THE SHOWERS.
EXPECT A NEAR FULL RECOVERY TO CLOSE TO 100 PERCENT FRIDAY MORNING.
TOTAL RAINFALL AMOUNTS MAY RANGE FROM TWO TENTHS TO ONE HALF AN
INCH FROM THE FRONT TOMORROW...WITH A FEW LOCALLY HIGHER AMOUNTS.
THE WINDS WILL BE FROM THE SOUTH AT 10 MPH OR LESS TONIGHT...THEN
INCREASE FROM THE SOUTH/SOUTHWEST AND SHIFT TO TO THE WEST AT 10
TO 20 MPH WITH A FEW GUSTS 30 TO 35 MPH DURING THE MID TO LATE
AFTERNOON WITH THE FRONTAL PASSAGE. THE WINDS WILL VEER TO THE
NORTHWEST OR NORTH AT 5 TO 10 MPH THU NIGHT.
&&
.HYDROLOGY...
NO WIDESPREAD HYDRO PROBLEMS ARE EXPECTED THE NEXT FIVE DAYS
ENDING MONDAY.
THE NEXT CHANCE OF SHOWERS AND ISOLD THUNDERSTORMS WILL BE
TONIGHT THROUGH TOMORROW ASSOCIATED WITH A COLD FRONT PASSING
THROUGH. AVERAGE BASIN RAINFALL LOOKS TO BE WELL UNDER AN INCH.
HOWEVER...ANY THUNDERSTORM COULD CONTAIN HEAVY RAINFALL WITH
LOCALIZED RAINFALL OF GREATER THAN A HALF AN INCH POSSIBLE. MOST
LOCATIONS WILL GET TWO TENTHS TO LESS THAN A HALF AN INCH OF
RAINFALL.
PONDING OF WATER ON ROADS AND OTHER LOW LYING AREAS MAY OCCUR. AT
THIS TIME...LITTLE OR NO RISES ARE EXPECTED ON MAIN STEM RIVERS.
DRY WEATHER RETURNS ON FRIDAY BUT THERE IS A CHANCE OF SHOWERS ON
SATURDAY WITH ANOTHER DISTURBANCE...AND DRY WEATHER RETURNS SUNDAY
INTO EARLY NEXT WEEK.
FOR DETAILS ON SPECIFIC AREA RIVERS AND LAKES...INCLUDING OBSERVED
AND FORECAST RIVER STAGES AND LAKE ELEVATIONS...PLEASE VISIT THE
ADVANCED HYDROLOGIC PREDICTION SERVICE /AHPS/ GRAPHS ON OUR WEBSITE.
&&
.ALY WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...NONE.
MA...NONE.
VT...NONE.
&&
$$
SYNOPSIS...HWJIV/WASULA
NEAR TERM...HWJIV/NAS/WASULA
SHORT TERM...WASULA
LONG TERM...IRL
AVIATION...BGM
FIRE WEATHER...HWJIV/WASULA
HYDROLOGY...HWJIV/WASULA
WWW.WEATHER.GOV/ALBANY
AREA FORECAST DISCUSSION
NWS MIAMI FL
944 PM EDT FRI SEP 12 2014
.UPDATE...
ONLY MADE SOME MINOR ADJUSTMENTS TO THE POP GRIDS THIS EVENING.
COULD HAVE LOWERED THEM EVEN MORE THAN I DID, BUT THESE TROPICAL
TYPE SMALL LOW LEVEL CIRCULATIONS CAN BEGIN TO DEVELOP CONVECTION
AT ANY TIME GIVEN THE SOUTHEASTERLY FLOW ON THE EAST SIDE WITH
DEEP TROPICAL AIRMASS. SO EVEN THOUGH NOT MUCH GOING ON AT THE
CURRENT TIME, WAS A LITTLE HESITANT IN MAKING TOO DRASTIC OF A CUT
IN THE POPS. THE HRRR KEEPS THE ACTION QUIET SO LATER UPDATES MAY
BE NEEDED TO LOWER CHANCES MORE IF TRENDS DICTATE.
KOB
&&
.PREV DISCUSSION... /ISSUED 739 PM EDT FRI SEP 12 2014/
AVIATION...
LOW PRESSURE CENTERED JUST NORTH OF NAPLES THIS EVENING WILL
CONTINUE DRIFTING WEST INTO THE GULF OF MEXICO...BUT WILL BE THE
MAJOR INFLUENCE ON SOUTH FLORIDA WEATHER THROUGH THE TAF PERIOD.
APPEARS TSRA THREAT OVERNIGHT IS MINIMAL...SO ELECTED TO HAVE VCSH
IN FORECAST INTO SATURDAY MORNING. BY 15Z...SCATTERED/NUMEROUS
SHOWERS/TSTMS EXPECTED...HANDLED NOW BY VCTS BUT TEMPO GROUPS MAY
BE NEEDED ONCE TIMING/COVERAGE BECOME MORE CERTAIN. ESE WINDS WILL
DIMINISH TO 5 KTS OR LESS TONIGHT...THEN INCREASE TO 10-15 KTS BY
SAT AFTN.
PREV DISCUSSION... /ISSUED 344 PM EDT FRI SEP 12 2014/
DISCUSSION...
RECENT WATER VAPOR IMAGERY AND THE LATEST GUIDANCE INDICATES AN
UPPER LEVEL LOW JUST TO THE NORTH OF THE NORTHERN BAHAMAS AND IS
FORECAST TO RETROGRADE WESTWARD TONIGHT INTO SATURDAY.
ELEVATED CHANCES OF SHOWERS AND THUNDERSTORMS ARE FORECAST ACROSS
THE REGION TONIGHT INTO SATURDAY. AS THE SURFACE LOW CONTINUES TO
TRACK WESTWARD TONIGHT...IT IS FORECAST TO ENTER THE GULF WATERS
WITH LOW LEVEL SOUTHEASTERLY WINDS FORECAST TO CONTINUE BRINGING
IN DEEP TROPICAL MOISTURE INTO THE REGION TONIGHT INTO SATURDAY.
FOR TONIGHT...THE AFOREMENTIONED UPPER LEVEL LOW IS FORECAST TO
DRIFT WESTWARD WITH 500 HPA VORTICITY FORECAST TO PASS ACROSS THE
REGION TONIGHT INTO SATURDAY. THUS THE INGREDIENTS FOR ADDITIONAL
SHOWERS AND THUNDERSTORMS WILL CONTINUE TONIGHT INTO SATURDAY WITH
ELEVATED POP`S INDICATED IN THE FORECAST.
FOR SATURDAY...WILE THE UPPER LEVEL LOW MAY BE LESS OF A FACTOR AS
IT IS FORECAST TO CONTINUE MOVING WESTWARD...THE SURFACE LOW IS
FORECAST TO BE IN THE EASTERN GULF WITH LOW LEVEL SOUTHEASTERLY
WINDS CONTINUING TO ADVECT ADDITIONAL DEEP MOISTURE INTO THE
REGION. NUMEROUS SHOWERS AND SCATTERED THUNDERSTORMS ARE FORECAST
FOR SATURDAY AFTERNOON AND EARLY EVENING HOURS. BY SUNDAY
TROPICAL MOISTURE IS FORECAST TO REMAIN ACROSS THE REGION WITH DAY
TIME HEATING LIKELY TO DEVELOP AFTERNOON SHOWERS AND
THUNDERSTORMS. THE EXTENDED GUIDANCE INDICATES SOME RELATIVELY
DRIER AIR ENTERING THE REGION EARLY NEXT WEEK.
MARINE...
WINDS ARE FORECAST TO BE FROM 10 TO 15 KNOTS THROUGH SATURDAY
THEN DECREASING INTO SUNDAY TO AROUND 10 KNOTS. SEAS 2 TO 3 FEET
POSSIBLE TODAY INTO SATURDAY THEN DECREASING TO 2 FEET OR LESS BY
SUNDAY.
&&
.MFL WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
AM...NONE.
GM...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS MIAMI FL
200 PM EDT THU SEP 11 2014
.AVIATION...
LARGE SHIELD OF MODERATE TO HEAVY RAINFALL ASSOCIATED WITH MID
LEVEL CIRCULATION JUST WEST OF THE BAHAMAS HAS REMAINED OFFSHORE
THUS FAR THIS AFTERNOON. HOWEVER...CONVECTIVE BANDS EMANATING FROM
THIS CIRCULATION CONTINUE TO PUSH INTO PALM BEACH COUNTY. LATEST
HRRR AND OTHER HI-RES MODELS SEEM TO BE RETRACTING THEIR DEPICTION
OF OVERALL COVERAGE OF HEAVY RAIN...BUT STILL SHOW A RATHER LARGE
AREA OF SHOWERS PUSHING ACROSS THE EAST COAST SITES THROUGH 00Z AS
THE CIRCULATION CENTER SLOWLY SLIDES TO THE WEST. THEREFORE PLACED
TEMPOS IN AT ALL EAST COAST SITES FOR SHOWERS AND MVFR CIGS
THROUGH 00Z. ISOLATED IFR CIGS/VSBYS ARE POSSIBLE WITHIN THE
HEAVIEST SHOWERS BUT SHOULD BE BRIEF AND LEFT OUT OF TAFS FOR NOW.
WINDS SHOULD BE LIGHT OVERNIGHT AND INTO THE MORNING HOURS
TOMORROW BEFORE BECOMING ESE AGAIN TOMORROW AFTERNOON WITH THE
CIRCULATION CENTER TO THE WEST OF THE EAST COAST SITES.
&&
.PREV DISCUSSION... /ISSUED 1049 AM EDT THU SEP 11 2014/
UPDATE...
ONLY SIGNIFICANT CHANGE TO THE FORECAST IS TO REDUCE POPS THIS
MORNING AS THERE HAS BEEN SOME WEAK SUBSIDENCE AHEAD OF THE WEAK
LOW OVER THE BAHAMAS. THE HRRR IS SHOWING THAT MOST CONVECTIVE
DEVELOPMENT OVER THE MAINLAND WILL HOLD OFF UNTIL AFTER 18Z. EVEN
THEN, MOST OF IT IS INDICATED TO BE OVER THE INTERIOR THIS
AFTERNOON. THE MODEL DOES THEN BRING SHOWERS AND THUNDERSTORMS TO
THE EASTERN COASTAL AREAS OF SOUTH FLORIDA THIS EVENING. THE ONLY
THREAT OF CONCERN RIGHT NOW IS A LOW CHANCE OF URBAN FLOODING DUE
TO SLOW MOVING HEAVY SHOWERS AND THUNDERSTORMS.
PREV DISCUSSION... /ISSUED 450 AM EDT THU SEP 11 2014/
DISCUSSION...
AN AREA OF LOW PRESSURE NEAR THE NORTHWEST BAHAMAS WILL DOMINATE
THE WEATHER DISCUSSION OVER THE NEXT COUPLE DAYS. MODELS ARE IN
GOOD AGREEMENT THAT THIS WEAK SYSTEM WILL MOVE SLOWLY WESTWARD
ACROSS THE NORTHWEST BAHAMAS AND THEN ACROSS SOUTH FLORIDA ON
FRIDAY. CONDITIONS ARE FORECAST TO BECOME UNFAVORABLE OVER THE LOW
TODAY AS SHEAR INCREASES. HOWEVER...THERE IS STILL A SLIGHT CHANCE
THAT THE SYSTEM MAY DEVELOP BEFORE MOVING INTO SOUTH FLORIDA...AND
THEN A MEDIUM CHANCE AFTER IT MOVES INTO THE GULF OF MEXICO OVER
THE WEEKEND. REGARDLESS OF DEVELOPMENT...THE MAIN IMPACT FOR
SOUTH FLORIDA WILL LIKELY BE LOCALLY HEAVY RAINFALL.
TODAY...THE WIND FIELD OVER/NEAR THE LOW IS LIGHT...AND WINDS ARE
FORECAST TO BE VERY LIGHT ACROSS THE REGION TODAY. A LIGHT
NORTHEASTERLY FLOW MAY BRIEFLY DEVELOP BEFORE SEA BREEZE
BOUNDARIES BECOME DOMINANT. STORM MOTION IS FORECAST TO BE
RELATIVELY SLOW TODAY...AND LOCALLY HEAVY RAINFALL IS POSSIBLE.
PONDING IN POORLY DRAINED AREAS AND LOCALIZED STREET FLOODING ARE
THE MAIN THREATS. RAIN CHANCES ARE 50-70% ACROSS THE
REGION. THE LATEST HRRR RUN SHOWS PRETTY HIGH COVERAGE OF RAIN
ACROSS THE REGION. HIGHS ARE FORECAST TO BE IN THE UPPER 80S TO
AROUND 90 DEGREES.
TONIGHT...THE WEAK AREA OF LOW PRESSURE WILL MOVE CLOSER TO THE
EAST COAST...IN THE VICINITY OF PALM BEACH COUNTY COAST BY
DAYBREAK. SCATTERED SHOWERS AND A FEW EMBEDDED STORMS ARE
FORECAST FOR THE EAST COAST METRO AREAS OVERNIGHT.
FRIDAY...THE AREA OF LOW PRESSURE IS FORECAST TO MOVE SLOWLY
ACROSS THE REGION...AND SHOWERS AND STORMS ARE LIKELY THROUGHOUT
THE DAY. LOCALLY HEAVY RAIN AND MINOR STREET FLOODING IS POSSIBLE.
CLOUD COVER AND RAINFALL IS FORECAST TO KEEP TEMPS IN THE 80S. THE
AREA OF LOW PRESSURE IS FORECAST TO MOVE SOUTHWEST INTO THE GULF
OF MEXICO FRIDAY NIGHT...AND RAIN CHANCES WILL CONTINUE ACROSS
COASTAL AREAS.
SATURDAY AND SUNDAY...DEEP MOISTURE WILL REMAIN ACROSS SOUTH
FLORIDA THROUGH THE WEEKEND. THE ECMWF KEEPS A TROUGH AXIS
LINGERING OVER THE REGION EXTENDING TO THE EAST OF THE AREA OF LOW
PRESSURE THROUGH SUNDAY. THE GFS MOVES THE SYSTEM QUICKLY
WESTWARD ACROSS THE GULF...WITH A RETURN OF THE DEEP EAST TO
SOUTHEAST FLOW OBSERVED OVER THE PAST SEVERAL DAYS ON SUNDAY AS
THE RIDGE BUILDS WESTWARD ACROSS THE REGION. SO RAIN CHANCES WILL
REMAIN IN THE LIKELY CATEGORY ON SATURDAY...AND THEN COME DOWN A
LITTLE ON SUNDAY.
HIGH PRESSURE WILL THEN BUILD ACROSS THE REGION EARLY NEXT
WEEK...WITH A MORE TYPICAL EASTERLY FLOW RAINY SEASON PATTERN.
MARINE...
A WEAK AREA OF LOW PRESSURE NEAR THE NORTHERN BAHAMAS IS FORECAST
TO PUSH SLOWLY WEST ACROSS THE LOCAL ATLANTIC WATERS TONIGHT AND
THEN INTO THE GULF WATERS FRIDAY NIGHT. THE NHC IS MONITORING
THIS DISTURBANCE...AND THIS COULD IMPACT THE FORECAST FOR FRIDAY
AND INTO THE WEEKEND. LIGHT WINDS ARE FORECAST TODAY...WITH
GENERALLY EAST TO SOUTHEAST WINDS FRIDAY THROUGH THE WEEKEND.
&&
.PRELIMINARY POINT TEMPS/POPS...
WEST PALM BEACH 75 86 76 87 / 40 60 20 60
FORT LAUDERDALE 76 88 77 88 / 40 60 30 70
MIAMI 75 86 77 88 / 30 70 30 60
NAPLES 74 89 75 90 / 30 60 30 70
&&
.MFL WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
AM...NONE.
GM...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS MIAMI FL
1049 AM EDT THU SEP 11 2014
.UPDATE...
ONLY SIGNIFICANT CHANGE TO THE FORECAST IS TO REDUCE POPS THIS
MORNING AS THERE HAS BEEN SOME WEAK SUBSIDENCE AHEAD OF THE WEAK
LOW OVER THE BAHAMAS. THE HRRR IS SHOWING THAT MOST CONVECTIVE
DEVELOPMENT OVER THE MAINLAND WILL HOLD OFF UNTIL AFTER 18Z. EVEN
THEN, MOST OF IT IS INDICATED TO BE OVER THE INTERIOR THIS
AFTERNOON. THE MODEL DOES THEN BRING SHOWERS AND THUNDERSTORMS TO
THE EASTERN COASTAL AREAS OF SOUTH FLORIDA THIS EVENING. THE ONLY
THREAT OF CONCERN RIGHT NOW IS A LOW CHANCE OF URBAN FLOODING DUE
TO SLOW MOVING HEAVY SHOWERS AND THUNDERSTORMS.
&&
.PREV DISCUSSION... /ISSUED 850 AM EDT THU SEP 11 2014/
AVIATION...
SHOWERS ARE LIKELY ALONG WITH A FEW THUNDERSTORMS ACROSS MUCH OF
THE AREA TODAY AS AN AREA OF LOW PRESSURE ACROSS THE BAHAMAS
PUSHES TO THE WEST. AS A RESULT...KEPT VCSH TRANSITIONING TO VCTS
AND THEN BACK TO VCSH AFTER 02Z AT ALL EAST COAST SITES THROUGH
THE PERIOD. WINDS WILL AGAIN BE GENERALLY EASTERLY AT ALL EAST
COAST SITES WITH A GULF BREEZE AT KAPF.
PREV DISCUSSION... /ISSUED 450 AM EDT THU SEP 11 2014/
DISCUSSION...
AN AREA OF LOW PRESSURE NEAR THE NORTHWEST BAHAMAS WILL DOMINATE
THE WEATHER DISCUSSION OVER THE NEXT COUPLE DAYS. MODELS ARE IN
GOOD AGREEMENT THAT THIS WEAK SYSTEM WILL MOVE SLOWLY WESTWARD
ACROSS THE NORTHWEST BAHAMAS AND THEN ACROSS SOUTH FLORIDA ON
FRIDAY. CONDITIONS ARE FORECAST TO BECOME UNFAVORABLE OVER THE LOW
TODAY AS SHEAR INCREASES. HOWEVER...THERE IS STILL A SLIGHT CHANCE
THAT THE SYSTEM MAY DEVELOP BEFORE MOVING INTO SOUTH FLORIDA...AND
THEN A MEDIUM CHANCE AFTER IT MOVES INTO THE GULF OF MEXICO OVER
THE WEEKEND. REGARDLESS OF DEVELOPMENT...THE MAIN IMPACT FOR
SOUTH FLORIDA WILL LIKELY BE LOCALLY HEAVY RAINFALL.
TODAY...THE WIND FIELD OVER/NEAR THE LOW IS LIGHT...AND WINDS ARE
FORECAST TO BE VERY LIGHT ACROSS THE REGION TODAY. A LIGHT
NORTHEASTERLY FLOW MAY BRIEFLY DEVELOP BEFORE SEA BREEZE
BOUNDARIES BECOME DOMINANT. STORM MOTION IS FORECAST TO BE
RELATIVELY SLOW TODAY...AND LOCALLY HEAVY RAINFALL IS POSSIBLE.
PONDING IN POORLY DRAINED AREAS AND LOCALIZED STREET FLOODING ARE
THE MAIN THREATS. RAIN CHANCES ARE 50-70% ACROSS THE
REGION. THE LATEST HRRR RUN SHOWS PRETTY HIGH COVERAGE OF RAIN
ACROSS THE REGION. HIGHS ARE FORECAST TO BE IN THE UPPER 80S TO
AROUND 90 DEGREES.
TONIGHT...THE WEAK AREA OF LOW PRESSURE WILL MOVE CLOSER TO THE
EAST COAST...IN THE VICINITY OF PALM BEACH COUNTY COAST BY
DAYBREAK. SCATTERED SHOWERS AND A FEW EMBEDDED STORMS ARE
FORECAST FOR THE EAST COAST METRO AREAS OVERNIGHT.
FRIDAY...THE AREA OF LOW PRESSURE IS FORECAST TO MOVE SLOWLY
ACROSS THE REGION...AND SHOWERS AND STORMS ARE LIKELY THROUGHOUT
THE DAY. LOCALLY HEAVY RAIN AND MINOR STREET FLOODING IS POSSIBLE.
CLOUD COVER AND RAINFALL IS FORECAST TO KEEP TEMPS IN THE 80S. THE
AREA OF LOW PRESSURE IS FORECAST TO MOVE SOUTHWEST INTO THE GULF
OF MEXICO FRIDAY NIGHT...AND RAIN CHANCES WILL CONTINUE ACROSS
COASTAL AREAS.
SATURDAY AND SUNDAY...DEEP MOISTURE WILL REMAIN ACROSS SOUTH
FLORIDA THROUGH THE WEEKEND. THE ECMWF KEEPS A TROUGH AXIS
LINGERING OVER THE REGION EXTENDING TO THE EAST OF THE AREA OF LOW
PRESSURE THROUGH SUNDAY. THE GFS MOVES THE SYSTEM QUICKLY
WESTWARD ACROSS THE GULF...WITH A RETURN OF THE DEEP EAST TO
SOUTHEAST FLOW OBSERVED OVER THE PAST SEVERAL DAYS ON SUNDAY AS
THE RIDGE BUILDS WESTWARD ACROSS THE REGION. SO RAIN CHANCES WILL
REMAIN IN THE LIKELY CATEGORY ON SATURDAY...AND THEN COME DOWN A
LITTLE ON SUNDAY.
HIGH PRESSURE WILL THEN BUILD ACROSS THE REGION EARLY NEXT
WEEK...WITH A MORE TYPICAL EASTERLY FLOW RAINY SEASON PATTERN.
MARINE...
A WEAK AREA OF LOW PRESSURE NEAR THE NORTHERN BAHAMAS IS FORECAST
TO PUSH SLOWLY WEST ACROSS THE LOCAL ATLANTIC WATERS TONIGHT AND
THEN INTO THE GULF WATERS FRIDAY NIGHT. THE NHC IS MONITORING
THIS DISTURBANCE...AND THIS COULD IMPACT THE FORECAST FOR FRIDAY
AND INTO THE WEEKEND. LIGHT WINDS ARE FORECAST TODAY...WITH
GENERALLY EAST TO SOUTHEAST WINDS FRIDAY THROUGH THE WEEKEND.
&&
.PRELIMINARY POINT TEMPS/POPS...
WEST PALM BEACH 88 75 86 76 / 60 40 60 20
FORT LAUDERDALE 89 76 88 77 / 60 40 60 30
MIAMI 88 75 86 77 / 60 30 70 30
NAPLES 90 74 89 75 / 60 30 60 30
&&
.MFL WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
AM...NONE.
GM...NONE.
&&
$$
SHORT TERM...13/SI
LONG TERM....84/AK
AREA FORECAST DISCUSSION
NWS MIAMI FL
850 AM EDT THU SEP 11 2014
.AVIATION...
SHOWERS ARE LIKELY ALONG WITH A FEW THUNDERSTORMS ACROSS MUCH OF
THE AREA TODAY AS AN AREA OF LOW PRESSURE ACROSS THE BAHAMAS
PUSHES TO THE WEST. AS A RESULT...KEPT VCSH TRANSITIONING TO VCTS
AND THEN BACK TO VCSH AFTER 02Z AT ALL EAST COAST SITES THROUGH
THE PERIOD. WINDS WILL AGAIN BE GENERALLY EASTERLY AT ALL EAST
COAST SITES WITH A GULF BREEZE AT KAPF.
&&
.PREV DISCUSSION... /ISSUED 450 AM EDT THU SEP 11 2014/
DISCUSSION...
AN AREA OF LOW PRESSURE NEAR THE NORTHWEST BAHAMAS WILL DOMINATE
THE WEATHER DISCUSSION OVER THE NEXT COUPLE DAYS. MODELS ARE IN
GOOD AGREEMENT THAT THIS WEAK SYSTEM WILL MOVE SLOWLY WESTWARD
ACROSS THE NORTHWEST BAHAMAS AND THEN ACROSS SOUTH FLORIDA ON
FRIDAY. CONDITIONS ARE FORECAST TO BECOME UNFAVORABLE OVER THE LOW
TODAY AS SHEAR INCREASES. HOWEVER...THERE IS STILL A SLIGHT CHANCE
THAT THE SYSTEM MAY DEVELOP BEFORE MOVING INTO SOUTH FLORIDA...AND
THEN A MEDIUM CHANCE AFTER IT MOVES INTO THE GULF OF MEXICO OVER
THE WEEKEND. REGARDLESS OF DEVELOPMENT...THE MAIN IMPACT FOR
SOUTH FLORIDA WILL LIKELY BE LOCALLY HEAVY RAINFALL.
TODAY...THE WIND FIELD OVER/NEAR THE LOW IS LIGHT...AND WINDS ARE
FORECAST TO BE VERY LIGHT ACROSS THE REGION TODAY. A LIGHT
NORTHEASTERLY FLOW MAY BRIEFLY DEVELOP BEFORE SEA BREEZE
BOUNDARIES BECOME DOMINANT. STORM MOTION IS FORECAST TO BE
RELATIVELY SLOW TODAY...AND LOCALLY HEAVY RAINFALL IS POSSIBLE.
PONDING IN POORLY DRAINED AREAS AND LOCALIZED STREET FLOODING ARE
THE MAIN THREATS. RAIN CHANCES ARE 50-70% ACROSS THE
REGION. THE LATEST HRRR RUN SHOWS PRETTY HIGH COVERAGE OF RAIN
ACROSS THE REGION. HIGHS ARE FORECAST TO BE IN THE UPPER 80S TO
AROUND 90 DEGREES.
TONIGHT...THE WEAK AREA OF LOW PRESSURE WILL MOVE CLOSER TO THE
EAST COAST...IN THE VICINITY OF PALM BEACH COUNTY COAST BY
DAYBREAK. SCATTERED SHOWERS AND A FEW EMBEDDED STORMS ARE
FORECAST FOR THE EAST COAST METRO AREAS OVERNIGHT.
FRIDAY...THE AREA OF LOW PRESSURE IS FORECAST TO MOVE SLOWLY
ACROSS THE REGION...AND SHOWERS AND STORMS ARE LIKELY THROUGHOUT
THE DAY. LOCALLY HEAVY RAIN AND MINOR STREET FLOODING IS POSSIBLE.
CLOUD COVER AND RAINFALL IS FORECAST TO KEEP TEMPS IN THE 80S. THE
AREA OF LOW PRESSURE IS FORECAST TO MOVE SOUTHWEST INTO THE GULF
OF MEXICO FRIDAY NIGHT...AND RAIN CHANCES WILL CONTINUE ACROSS
COASTAL AREAS.
SATURDAY AND SUNDAY...DEEP MOISTURE WILL REMAIN ACROSS SOUTH
FLORIDA THROUGH THE WEEKEND. THE ECMWF KEEPS A TROUGH AXIS
LINGERING OVER THE REGION EXTENDING TO THE EAST OF THE AREA OF LOW
PRESSURE THROUGH SUNDAY. THE GFS MOVES THE SYSTEM QUICKLY
WESTWARD ACROSS THE GULF...WITH A RETURN OF THE DEEP EAST TO
SOUTHEAST FLOW OBSERVED OVER THE PAST SEVERAL DAYS ON SUNDAY AS
THE RIDGE BUILDS WESTWARD ACROSS THE REGION. SO RAIN CHANCES WILL
REMAIN IN THE LIKELY CATEGORY ON SATURDAY...AND THEN COME DOWN A
LITTLE ON SUNDAY.
HIGH PRESSURE WILL THEN BUILD ACROSS THE REGION EARLY NEXT
WEEK...WITH A MORE TYPICAL EASTERLY FLOW RAINY SEASON PATTERN.
MARINE...
A WEAK AREA OF LOW PRESSURE NEAR THE NORTHERN BAHAMAS IS FORECAST
TO PUSH SLOWLY WEST ACROSS THE LOCAL ATLANTIC WATERS TONIGHT AND
THEN INTO THE GULF WATERS FRIDAY NIGHT. THE NHC IS MONITORING
THIS DISTURBANCE...AND THIS COULD IMPACT THE FORECAST FOR FRIDAY
AND INTO THE WEEKEND. LIGHT WINDS ARE FORECAST TODAY...WITH
GENERALLY EAST TO SOUTHEAST WINDS FRIDAY THROUGH THE WEEKEND.
&&
.PRELIMINARY POINT TEMPS/POPS...
WEST PALM BEACH 88 75 86 76 / 60 40 60 20
FORT LAUDERDALE 89 76 88 77 / 60 40 60 30
MIAMI 88 75 86 77 / 60 30 70 30
NAPLES 90 74 89 75 / 50 30 60 30
&&
.MFL WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
AM...NONE.
GM...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS MIAMI FL
450 AM EDT THU SEP 11 2014
.DISCUSSION...
AN AREA OF LOW PRESSURE NEAR THE NORTHWEST BAHAMAS WILL DOMINATE
THE WEATHER DISCUSSION OVER THE NEXT COUPLE DAYS. MODELS ARE IN
GOOD AGREEMENT THAT THIS WEAK SYSTEM WILL MOVE SLOWLY WESTWARD
ACROSS THE NORTHWEST BAHAMAS AND THEN ACROSS SOUTH FLORIDA ON
FRIDAY. CONDITIONS ARE FORECAST TO BECOME UNFAVORABLE OVER THE LOW
TODAY AS SHEAR INCREASES. HOWEVER...THERE IS STILL A SLIGHT CHANCE
THAT THE SYSTEM MAY DEVELOP BEFORE MOVING INTO SOUTH FLORIDA...AND
THEN A MEDIUM CHANCE AFTER IT MOVES INTO THE GULF OF MEXICO OVER
THE WEEKEND. REGARDLESS OF DEVELOPMENT...THE MAIN IMPACT FOR
SOUTH FLORIDA WILL LIKELY BE LOCALLY HEAVY RAINFALL.
TODAY...THE WIND FIELD OVER/NEAR THE LOW IS LIGHT...AND WINDS ARE
FORECAST TO BE VERY LIGHT ACROSS THE REGION TODAY. A LIGHT
NORTHEASTERLY FLOW MAY BRIEFLY DEVELOP BEFORE SEA BREEZE
BOUNDARIES BECOME DOMINANT. STORM MOTION IS FORECAST TO BE
RELATIVELY SLOW TODAY...AND LOCALLY HEAVY RAINFALL IS POSSIBLE.
PONDING IN POORLY DRAINED AREAS AND LOCALIZED STREET FLOODING ARE
THE MAIN THREATS. RAIN CHANCES ARE 50-70% ACROSS THE
REGION. THE LATEST HRRR RUN SHOWS PRETTY HIGH COVERAGE OF RAIN
ACROSS THE REGION. HIGHS ARE FORECAST TO BE IN THE UPPER 80S TO
AROUND 90 DEGREES.
TONIGHT...THE WEAK AREA OF LOW PRESSURE WILL MOVE CLOSER TO THE
EAST COAST...IN THE VICINITY OF PALM BEACH COUNTY COAST BY
DAYBREAK. SCATTERED SHOWERS AND A FEW EMBEDDED STORMS ARE
FORECAST FOR THE EAST COAST METRO AREAS OVERNIGHT.
FRIDAY...THE AREA OF LOW PRESSURE IS FORECAST TO MOVE SLOWLY
ACROSS THE REGION...AND SHOWERS AND STORMS ARE LIKELY THROUGHOUT
THE DAY. LOCALLY HEAVY RAIN AND MINOR STREET FLOODING IS POSSIBLE.
CLOUD COVER AND RAINFALL IS FORECAST TO KEEP TEMPS IN THE 80S. THE
AREA OF LOW PRESSURE IS FORECAST TO MOVE SOUTHWEST INTO THE GULF
OF MEXICO FRIDAY NIGHT...AND RAIN CHANCES WILL CONTINUE ACROSS
COASTAL AREAS.
SATURDAY AND SUNDAY...DEEP MOISTURE WILL REMAIN ACROSS SOUTH
FLORIDA THROUGH THE WEEKEND. THE ECMWF KEEPS A TROUGH AXIS
LINGERING OVER THE REGION EXTENDING TO THE EAST OF THE AREA OF LOW
PRESSURE THROUGH SUNDAY. THE GFS MOVES THE SYSTEM QUICKLY
WESTWARD ACROSS THE GULF...WITH A RETURN OF THE DEEP EAST TO
SOUTHEAST FLOW OBSERVED OVER THE PAST SEVERAL DAYS ON SUNDAY AS
THE RIDGE BUILDS WESTWARD ACROSS THE REGION. SO RAIN CHANCES WILL
REMAIN IN THE LIKELY CATEGORY ON SATURDAY...AND THEN COME DOWN A
LITTLE ON SUNDAY.
HIGH PRESSURE WILL THEN BUILD ACROSS THE REGION EARLY NEXT
WEEK...WITH A MORE TYPICAL EASTERLY FLOW RAINY SEASON PATTERN.
&&
.AVIATION...
INCREASING RAINFALL CHANCES WILL REMAIN POSSIBLE AS A WEAK AREA OF
LOW PRESSURE TRACKS WESTWARD INTO THE LOCAL AREA TODAY THROUGH
FRIDAY. WINDS WILL REMAIN LIGHT AND MAINLY DRIVEN BY THE LAND/SEA
BREEZES AND AFTERNOON CONVECTION. WILL INCLUDE VCTS AT ALL SITES
AFTER 15Z AND UPDATE AS CONDITIONS EVOLVE. /85
&&
.MARINE...
A WEAK AREA OF LOW PRESSURE NEAR THE NORTHERN BAHAMAS IS FORECAST
TO PUSH SLOWLY WEST ACROSS THE LOCAL ATLANTIC WATERS TONIGHT AND
THEN INTO THE GULF WATERS FRIDAY NIGHT. THE NHC IS MONITORING
THIS DISTURBANCE...AND THIS COULD IMPACT THE FORECAST FOR FRIDAY
AND INTO THE WEEKEND. LIGHT WINDS ARE FORECAST TODAY...WITH
GENERALLY EAST TO SOUTHEAST WINDS FRIDAY THROUGH THE WEEKEND.
&&
.PRELIMINARY POINT TEMPS/POPS...
WEST PALM BEACH 88 75 86 76 / 60 40 60 20
FORT LAUDERDALE 89 76 88 77 / 60 40 60 30
MIAMI 88 75 86 77 / 60 30 70 30
NAPLES 90 74 89 75 / 50 30 60 30
&&
.MFL WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
AM...NONE.
GM...NONE.
&&
$$
SHORT TERM...84/AK
LONG TERM....84/AK
AVIATION...85/AG
AREA FORECAST DISCUSSION
NWS JACKSONVILLE FL
928 PM EDT WED SEP 10 2014
.UPDATE...MUCH LESS CONVECTION THIS AFTERNOON AND EVE DUE TO DRY AND
MORE STABLE AIR ALOFT. A FEW REMAINING SHOWERS ACROSS THE SUWANNEE
VALLEY WILL CONTINUE TO MOVE WEST AND WEAKEN. WILL KEEP ISOLATED POPS
GOING TONIGHT FOR THE COASTAL WATERS AND LOWER ACROSS THE SUWANNEE
VALLEY THE NEXT COUPLE OF HOURS. ADEQUATE LOW LEVEL MOISTURE ALONG
WITH LIGHT WINDS AND MOSTLY CLEAR SKIES RESULTS IN PATCHY LATE NIGHT
DENSE FOG ACROSS THE INLAND AREAS.
&&
.AVIATION...
ALTHOUGH CONDITIONS APPEAR FAVORABLE FOR FOG DEVELOPMENT
OVERNIGHT...THE MAJORITY OF THE FOG TOOLS SEEM TO BE DOWNPLAYING
THIS THREAT. IN FACT...THE HRRR DOES NOT REALLY INDICATE MUCH IN THE
WAY OF FOG AT ALL. NEVERTHELESS...GIVEN THE CONDITIONS...WOULD
EXPECT AT LEAST PATCHY SHALLOW FOG DEVELOPMENT LATE
TONIGHT...POSSIBLY EVEN SOME PATCHY DENSE FOG AT THE MORE PRONE
LOCATIONS SUCH AS VQQ. OTHERWISE...VFR WILL PREVAIL THROUGH THIS TAF
PERIOD.
&&
.MARINE...NO HEADLINES. SOUTHEAST WINDS 10 KNOTS. SEAS 2 TO 3 FEET.
ISOLATED SHOWERS AND THUNDERSTORMS.
RIP CURRENTS: LOW RISK.
&&
.PRELIMINARY POINT TEMPS/POPS...
AMG 71 91 74 92 / 20 30 20 20
SSI 74 85 75 85 / 10 10 10 10
JAX 73 89 73 88 / 10 20 10 20
SGJ 74 86 74 85 / 10 10 10 10
GNV 71 89 71 89 / 20 30 20 20
OCF 71 89 72 89 / 20 30 30 20
&&
.JAX WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
GA...NONE.
AM...NONE.
&&
$$
SHULER/PETERSON/WALSH
AREA FORECAST DISCUSSION...UPDATED
NWS PEACHTREE CITY GA
154 PM EDT THU SEP 11 2014
.PREV DISCUSSION...
UPDATE...
/ISSUED 1122 AM EDT THU SEP 11 2014/
ALREADY SHOWERS ACROSS FAR NORTH GEORGIA. BOTH HRRR AND LOCAL WRF
INCREASE DEVELOPMENT INTO THE AFTERNOON HOWEVER TWO OTHER HI RES
MODELS ARE MUCH MORE CONSERVATIVE IN TERMS OF PRECIPITATION.
CONSIDERING THE TRENDS OF THE HRRR THIS SUMMER...IT MAY BE
SLIGHTLY OVERDONE. UPDATED POPS THIS MORNING LEAN TOWARDS THE
BETTER CHANCES OF PRECIPITATION...GIVEN APPROACHING FRONTAL
BOUNDARY...BUT DO NOT SHOW BETTER PRECIP CHANCES AS FAR SOUTH AS
THE HRRR AND THE LOCAL WRF. WILL HAVE TO CONTINUE TO MONITOR THE
PRECIP TRENDS THOUGH FOR FUTURE UPDATES.
11
SHORT TERM /TODAY THROUGH FRIDAY/...
/ISSUED AT 456 AM EDT THU SEP 11 2014/
MODELS IN CLOSE AGREEMENT THROUGH THE LONG TERM. SURFACE FRONT AND
ASSOCIATED SHORT WAVE WILL MOVE INTO THE TENNESSEE VALLEY TODAY AND
THIS WILL INCREASE THE RISK OF SHOWERS AND TSTORMS OVER NORTH GA
THIS AFTERNOON. ALTHOUGH SHEAR IS NOT IMPRESSIVE...SBCAPES ARE
RUNNING IN THE 1500 TO 2500 DEPENDING ON THE MODEL WHICH COULD
BE ENOUGH TO PRODUCE STRONG STORMS WITH GUSTY WINDS. THE
INHIBITING FACTOR TO STRONG STORMS WILL BE THE H5 HIGH SITTING
OVER THE GA/AL BORDER NEAR CSG. PROXIMITY TO THIS COULD KEEP
TSTORMS FROM GOING SEVERE...HOWEVER THIS WILL NEED TO BE WATCHED. A
DIFFERENT STORY ON FRIDAY AS THE H5 HIGH WEAKENS AND THE SURFACE
FRONT DROPS INTO THE STATE. CONVERGENCE ALONG THE FRONT AS WELL AS
CAPES IN THE 2000 TO 2500 RANGE BY ALL MODELS WILL BE ENOUGH FOR A
FEW STRONG TO SEVERE STORMS TO DEVELOP DURING FRIDAY
AFTERNOON...MAINLY ACROSS NORTH GEORGIA.
17
LONG TERM /FRIDAY NIGHT THROUGH WEDNESDAY/...
/ISSUED AT 456 AM EDT THU SEP 11 2014/
EXTENDED MODELS CONSISTENT WITH SHOWING AFOREMENTIONED SHORT-TERM
FRONT STALLED ACROSS THE STATE SATURDAY AS A SECONDARY FRONT
APPROACHES THE AREA. UPPER LOW TRACKING ACROSS THE SOUTHERN GREAT
LAKES WILL PULL THE SECOND FRONT INTO THE REGION QUICKLY BEHIND
THE FIRST...WITH AMPLE MOISTURE POSITIONED ACROSS THE STATE
SATURDAY THROUGH EARLY NEXT WEEK AS BOUNDARIES BECOME STATIONARY
AND PILE UP ACROSS CENTRAL GEORGIA. THESE FRONTS WILL SERVE AS A
FOCUS FOR ENHANCED SHOWERS AND THUNDERSTORMS ACROSS THE STATE. NOT
UNTIL A SHORTWAVE SWEEPS INTO THE REGION TUESDAY AND KICKS THE
STATIONARY FRONTS EASTWARD DOES THE STATE REALLY GET TO SEE SOME
DRIER AIR MOVE INTO THE STATE.
FOR NOW...HAVE OPTED TO CONTINUE WITH GOOD CHANCE TO LIKELY POPS
ACROSS A VAST MAJORITY OF THE AREA SATURDAY THROUGH MONDAY. INTO
MID WEEK NEXT WEEK THE EXTENDED MODELS DISAGREE WITH THE EXTENT
THE DRIER AIR PUSHES INTO THE STATE AND WITH A SERIES OF UPPER
LEVEL DISTURBANCES THROUGH THE AREA. AS A RESULT...ASIDE FROM ZERO
POPS IN FAR NW GEORGIA ON SUNDAY NIGHT AND TUESDAY NIGHT...CARRY
AT LEAST GOOD CHANCE POPS ACROSS THE STATE EACH AFTERNOON...AND
AT LEAST SLIGHT CHANCE EACH OVERNIGHT.
MODELS ARE INDICATING THAT COOLER TEMPERATURES ARE IN STORE FOR
THE STATE BY THE WEEKEND...ESPECIALLY WITH THE INFLUENCE OF THE
PRECIPITATION AND CLOUDS. ANTICIPATE AN OVERALL COOLING TREND
THROUGH THE WEEK...AND BY THE LATTER HALF OF NEXT WEEK COULD BE
BELOW NORMAL FOR TEMPERATURES.
AS OF NOW...WEEKEND QPF IS EXPECTED TO BE 0.75 TO 1.5
INCHES...WITH THE HIGHEST AMOUNTS GENERALLY NOSING INTO THE STATE
FROM THE CAROLINAS. LOCALLY HEAVIER AMOUNTS CAN BE EXPECTED. AT
THIS TIME...GUIDANCE SUGGESTS MUCH OF THE STATE CAN HANDLE THIS
AMOUNT OF RAINFALL AND WILL NOT ISSUE ANY KIND OF WATCH AT THIS TIME.
31
&&
.AVIATION...
18Z UPDATE...
A BIT OF UNCERTAINTY IN TERMS OF SHRA/TSRA POTENTIAL AT NORTHERN
SITES. THINK SOME DEVELOPMENT WILL DRIFT INTO THE ATL SITES AT
SOME POINT. ADVERTISING TSRA IN THE TAFS SINCE THERE IS SOME
INSTABILITY...BUT BASED ON CURRENT RADAR TRENDS...COULD END UP
BEING JUST SHRA. CHANCES DECREASE INTO AHN AND THEN EVEN MORE INTO
MCN AND CSG.
//ATL CONFIDENCE...18Z UPDATE...
HIGH CONFIDENCE ON WIND. MEDIUM CONFIDENCE ON CIGS AND VSBYS.
11
&&
.PRELIMINARY POINT TEMPS/POPS...
ATHENS 90 71 90 70 / 30 30 60 60
ATLANTA 88 72 89 72 / 40 30 50 50
BLAIRSVILLE 82 67 81 65 / 60 50 60 60
CARTERSVILLE 88 71 89 69 / 50 40 50 50
COLUMBUS 91 73 93 72 / 20 20 50 50
GAINESVILLE 85 71 87 69 / 40 30 60 60
MACON 92 71 93 71 / 20 10 50 50
ROME 89 70 89 69 / 50 50 60 50
PEACHTREE CITY 89 70 90 69 / 30 20 50 50
VIDALIA 92 72 93 72 / 20 10 40 40
&&
.FFC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...11
LONG TERM....BAKER
AVIATION...11
AREA FORECAST DISCUSSION...UPDATED
NWS PEACHTREE CITY GA
1122 AM EDT THU SEP 11 2014
.UPDATE...
ALREADY SHOWERS ACROSS FAR NORTH GEORGIA. BOTH HRRR AND LOCAL WRF
INCREASE DEVELOPMENT INTO THE AFTERNOON HOWEVER TWO OTHER HI RES
MODELS ARE MUCH MORE CONSERVATIVE IN TERMS OF PRECIPITATION.
CONSIDERING THE TRENDS OF THE HRRR THIS SUMMER...IT MAY BE
SLIGHTLY OVERDONE. UPDATED POPS THIS MORNING LEAN TOWARDS THE
BETTER CHANCES OF PRECIPITATION...GIVEN APPROACHING FRONTAL
BOUNDARY...BUT DO NOT SHOW BETTER PRECIP CHANCES AS FAR SOUTH AS
THE HRRR AND THE LOCAL WRF. WILL HAVE TO CONTINUE TO MONITOR THE
PRECIP TRENDS THOUGH FOR FUTURE UPDATES.
11
&&
.PREV DISCUSSION...
SHORT TERM /TODAY THROUGH FRIDAY/...
/ISSUED AT 456 AM EDT THU SEP 11 2014/
MODELS IN CLOSE AGREEMENT THROUGH THE LONG TERM. SURFACE FRONT AND
ASSOCIATED SHORT WAVE WILL MOVE INTO THE TENNESSEE VALLEY TODAY AND
THIS WILL INCREASE THE RISK OF SHOWERS AND TSTORMS OVER NORTH GA
THIS AFTERNOON. ALTHOUGH SHEAR IS NOT IMPRESSIVE...SBCAPES ARE
RUNNING IN THE 1500 TO 2500 DEPENDING ON THE MODEL WHICH COULD
BE ENOUGH TO PRODUCE STRONG STORMS WITH GUSTY WINDS. THE
INHIBITING FACTOR TO STRONG STORMS WILL BE THE H5 HIGH SITTING
OVER THE GA/AL BORDER NEAR CSG. PROXIMITY TO THIS COULD KEEP
TSTORMS FROM GOING SEVERE...HOWEVER THIS WILL NEED TO BE WATCHED. A
DIFFERENT STORY ON FRIDAY AS THE H5 HIGH WEAKENS AND THE SURFACE
FRONT DROPS INTO THE STATE. CONVERGENCE ALONG THE FRONT AS WELL AS
CAPES IN THE 2000 TO 2500 RANGE BY ALL MODELS WILL BE ENOUGH FOR A
FEW STRONG TO SEVERE STORMS TO DEVELOP DURING FRIDAY
AFTERNOON...MAINLY ACROSS NORTH GEORGIA.
17
LONG TERM /FRIDAY NIGHT THROUGH WEDNESDAY/...
/ISSUED AT 456 AM EDT THU SEP 11 2014/
EXTENDED MODELS CONSISTENT WITH SHOWING AFOREMENTIONED SHORT-TERM
FRONT STALLED ACROSS THE STATE SATURDAY AS A SECONDARY FRONT
APPROACHES THE AREA. UPPER LOW TRACKING ACROSS THE SOUTHERN GREAT
LAKES WILL PULL THE SECOND FRONT INTO THE REGION QUICKLY BEHIND
THE FIRST...WITH AMPLE MOISTURE POSITIONED ACROSS THE STATE
SATURDAY THROUGH EARLY NEXT WEEK AS BOUNDARIES BECOME STATIONARY
AND PILE UP ACROSS CENTRAL GEORGIA. THESE FRONTS WILL SERVE AS A
FOCUS FOR ENHANCED SHOWERS AND THUNDERSTORMS ACROSS THE STATE. NOT
UNTIL A SHORTWAVE SWEEPS INTO THE REGION TUESDAY AND KICKS THE
STATIONARY FRONTS EASTWARD DOES THE STATE REALLY GET TO SEE SOME
DRIER AIR MOVE INTO THE STATE.
FOR NOW...HAVE OPTED TO CONTINUE WITH GOOD CHANCE TO LIKELY POPS
ACROSS A VAST MAJORITY OF THE AREA SATURDAY THROUGH MONDAY. INTO
MID WEEK NEXT WEEK THE EXTENDED MODELS DISAGREE WITH THE EXTENT
THE DRIER AIR PUSHES INTO THE STATE AND WITH A SERIES OF UPPER
LEVEL DISTURBANCES THROUGH THE AREA. AS A RESULT...ASIDE FROM ZERO
POPS IN FAR NW GEORGIA ON SUNDAY NIGHT AND TUESDAY NIGHT...CARRY
AT LEAST GOOD CHANCE POPS ACROSS THE STATE EACH AFTERNOON...AND
AT LEAST SLIGHT CHANCE EACH OVERNIGHT.
MODELS ARE INDICATING THAT COOLER TEMPERATURES ARE IN STORE FOR
THE STATE BY THE WEEKEND...ESPECIALLY WITH THE INFLUENCE OF THE
PRECIPITATION AND CLOUDS. ANTICIPATE AN OVERALL COOLING TREND
THROUGH THE WEEK...AND BY THE LATTER HALF OF NEXT WEEK COULD BE
BELOW NORMAL FOR TEMPERATURES.
AS OF NOW...WEEKEND QPF IS EXPECTED TO BE 0.75 TO 1.5
INCHES...WITH THE HIGHEST AMOUNTS GENERALLY NOSING INTO THE STATE
FROM THE CAROLINAS. LOCALLY HEAVIER AMOUNTS CAN BE EXPECTED. AT
THIS TIME...GUIDANCE SUGGESTS MUCH OF THE STATE CAN HANDLE THIS
AMOUNT OF RAINFALL AND WILL NOT ISSUE ANY KIND OF WATCH AT THIS TIME.
31
AVIATION...
12Z UPDATE...
/ISSUED 729 AM EDT THU SEP 11 2014/
NOT A CONTINUOUS CLOUD COVER ACROSS THE FORECAST AREA WITH POCKETS
OF IFR CLOUDS OVER CENTRAL GA AND POCKES OF 3000 TO 4000 FT CIGS
ACROSS THE REST OF THE FORECAST AREA. ALL AREAS SHOULD BE VFR WITH
INCREASING CLOUD COVER BY LATE THIS MORNING...AND REMAIN VFR FOR THE
REMAINDER OF THE FORECAST. DO EXPECT A MOSTLY BROKEN CLOUD COVER
ACROSS NORTH GA THROUGH THE FORECAST WHILE CENTRAL GA SHOULD BE
SCT-BKN. WINDS WILL BE WEST TO SOUTHWEST WITH SPEEDS OF 6 KTS OR
LESS TODAY...GOING NEAR CALM AFTER SUNSET THIS EVENING. ISOLATED
SHOWERS HAVE ALREADY DEVELOPED ACROSS NORTH GA AND WHILE THERE COULD
BE ISOLATED TSRA THIS AFTERNOON OVER THE FORECAST AREA...THE BEST
CHANCES WILL REMAIN NORTH OF THE TAF SITES.
//ATL CONFIDENCE...12Z UPDATE...
MEDIUM CONFIDENCE ON CIGS.
HIGH CONFIDENCE ON REMAINING ELEMENTS.
17
&&
.PRELIMINARY POINT TEMPS/POPS...
ATHENS 90 71 90 70 / 40 40 60 60
ATLANTA 88 72 89 72 / 40 40 50 50
BLAIRSVILLE 82 67 81 65 / 60 50 60 60
CARTERSVILLE 88 71 89 69 / 50 50 60 50
COLUMBUS 91 73 93 72 / 20 20 40 40
GAINESVILLE 85 71 87 69 / 50 50 60 60
MACON 92 71 93 71 / 20 20 40 40
ROME 89 70 89 69 / 50 50 60 50
PEACHTREE CITY 89 70 90 69 / 30 30 50 40
VIDALIA 92 72 93 72 / 20 20 40 40
&&
.FFC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...11
LONG TERM....BAKER
AVIATION...11
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
302 PM CDT THU SEP 11 2014
.DISCUSSION...
240 PM...FORECAST CONCERNS INCLUDE MUCH BELOW NORMAL TEMPERATURES
AND CHANCES FOR SHOWERS THROUGH SATURDAY AND AGAIN ON MONDAY.
STRATUS DECK HAS REMAINED MOSTLY OVERCAST TODAY AND THAT HAS HELD
TEMPS IN THE LOWER/MID 50S MOST AREAS...SOME 20 TO 25 DEGREES
BELOW NORMAL FOR MID SEPTEMBER. SEE CLIMATE SECTION BELOW FOR
RECORDS. CLOUD COVER IS EXPECTED TO REMAIN AT LEAST BROKEN IF NOT
OVERCAST OVERNIGHT INTO FRIDAY MORNING...SO NOT EXPECTING MUCH OF
A SWING IN TEMPS WITH LOWS TONIGHT IN THE MID/UPPER 40S.
AS COLDER AIR CONTINUES TO SPREAD ACROSS THE AREA...A FEW LAKE
EFFECT RAIN SHOWERS HAVE DEVELOPED OVER THE SOUTHEASTERN PART OF
THE LAKE. AS HIGH PRESSURE MOVES NORTH OF THE AREA TONIGHT...
WINDS WILL TURN MORE NORTHEAST AND THESE LAKE EFFECT RAIN SHOWERS
WILL BEGIN TO AFFECT NORTHEAST IL OVERNIGHT INTO FRIDAY MORNING.
COVERAGE REMAINS A BIT UNCERTAIN AND HAVE ONLY BUMPED POPS UP TO
LOW CHANCE. TRENDS WILL NEED TO BE MONITORED LATER TONIGHT WITH
THE POSSIBILITY THAT POPS WILL NEED TO BE BUMPED UP FURTHER.
LAKE EFFECT RAIN SHOWERS WILL CONTINUE INLAND ACROSS NORTHERN IL
FRIDAY MORNING AS FLOW TURNS MORE EAST/NORTHEAST. CLOUD COVER WILL
LIKELY REMAIN MOSTLY CLOUDY AND THIS COULD LIMIT TEMPS TO JUST THE
50S AGAIN ON FRIDAY. SOUTHERN AREAS MAY SEE A FEW BREAKS WITH THE
POTENTIAL TO REACH 60...BUT OVERALL FRIDAY WILL CONTINUE MUCH
BELOW NORMAL.
AN UPPER WAVE WILL MOVE ACROSS THE REGION FRIDAY AFTERNOON INTO
FRIDAY EVENING WITH SHOWERS/LIGHT RAIN SPREADING ACROSS THE
NORTHWEST CWA IN THE AFTERNOON THEN ACROSS MUCH OF THE AREA EARLY
FRIDAY EVENING. BUMPED POPS UP SOME...WITH LIKELY OVER THE
NORTHERN TWO THIRDS OF THE CWA...POSSIBLE POPS WILL NEED TO BE
INCREASED HERE AS WELL...THOUGH TOTAL QFP AMOUNTS SHOULD BE IN THE
0.25 TO 0.5 INCH RANGE. THIS WAVE IS FAIRLY PROGRESSIVE...SO
TRIMMED POPS FROM THE WEST OVERNIGHT. LAKE EFFECT RAIN SHOWERS MAY
CONTINUE INTO NORTHWEST INDIANA SATURDAY MORNING BEFORE ENDING IN
THE AFTERNOON.
DESPITE SOME SUNSHINE SATURDAY...AIRMASS WILL BE EVEN COLDER THAN
TODAY AND FRIDAY. NOT SURE HOW MUCH MID SEPTEMBER SUN WILL AID
TEMP INCREASE SO MAINTAINED JUST LOWER 60S FOR HIGHS. HIGH
PRESSURE PASSES ACROSS THE REGION SATURDAY NIGHT INTO SUNDAY
MORNING WITH LOWS DIPPING INTO THE LOWER 40S MOST AREAS...BUT
WARMER IN THE IMMEDIATE CHICAGO METRO AREA.
ANOTHER FAST MOVING WAVE WILL MOVE ACROSS THE AREA MONDAY
BRINGING ANOTHER CHANCE OF SHOWERS. DEPENDING ON TIMING...CLOUD
COVER AND PRECIP COULD HOLD TEMPS DOWN MONDAY BUT FOR NOW HAVE
MAINTAINED 60S. BEYOND MONDAY...HIGH PRESSURE SPREADS ACROSS THE
REGION WITH DRY WEATHER EXPECTED MID WEEK BUT TEMPS STILL BELOW
NORMAL. CMS
&&
.CLIMATE...
915 AM CDT SEP 11 2014
AN UNSEASONABLY COOL AIR MASS OVER THE REGION INTO THE WEEKEND
COULD PUT SOME RECORD TEMPERATURES IN JEOPARDY AT CHICAGO AND
ROCKFORD. RECORD LOW MAX TEMPERATURES ARE MOST LIKELY TO BE
THREATENED.
RECORD LOW MAX TEMPERATURES SEPTEMBER 11-13
-------------------------------------------
SEPTEMBER 11 SEPTEMBER 12 SEPTEMBER 13
------------ ------------ ------------
CHICAGO 61/1940 53/1902 55/1880
ROCKFORD 55/1914 56/1943 55/1970
RC
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 20Z...
* MVFR CIGS THROUGH THE PERIOD...WITH POTENTIAL FOR IFR LATE
TONIGHT INTO FRIDAY MORNING.
* NORTH-NORTHEAST WINDS 360-030 DEG AT OR BELOW 10 KT INTO THIS
EVENING.
* LAKE EFFECT SHOWERS LATE TONIGHT INTO FRIDAY MORNING.
* NORTH-NORTHEAST WINDS AROUND 10 KT BECOMING NORTHEAST ON FRIDAY.
* RAIN SHOWERS MOVING INTO AREA LATE FRIDAY AFTERNOON...WITH
PREVAILING RAIN AND CIG/VSBY IMPACTS MORE LIKELY FRIDAY EVE.
RC
//DISCUSSION...UPDATED 18Z...
UNSEASONABLY COOL AIR MASS OVER THE REGION IS RESULTING IN SEVERAL
CONCERNS THIS PERIOD. MOISTURE LOCKED UNDER INVERSION IS KEEPING
STRATUS DECK IN PLACE THIS AFTERNOON AND NOW EXPECT PRIMARILY MVFR
CIGS THROUGH THE PERIOD. THE COOL AIR MASS MOVING OVER THE MILD
LAKE WATERS WILL LIKELY RESULT IN THE DEVELOPMENT OF LAKE EFFECT
SHOWERS LATE TONIGHT INTO FRIDAY MORNING. HIGHER RESOLUTION
GUIDANCE HINTS THAT DECENT BAND COULD EVEN SET UP INTO NORTHWEST
INDIANA INITIALLY AND THEN GRADUALLY SHIFT NORTHEAST. HAVE MEDIUM
TO HIGH CONFIDENCE THAT THERE WILL BE SHOWERS AROUND...BUT LOW
CONFIDENCE IN DIRECT IMPACTS TO ORD/MDW/GYY...THUS HAVE CARRIED
VCSH MENTION. IF SHRA ARE MORE ORGANIZED AND DIRECTLY IMPACT
TERMINALS...THERE COULD BE IMPACTS TO VSBY.
ONSHORE FLOW IS EXPECTED TO ALSO RESULT IN LOWERING OF MVFR
CIGS AT EASTERN TERMINALS...WITH SOME GUIDANCE MEMBERS INDICATING
POTENTIAL FOR IFR. HAVE HINTED AT THIS WITH SCT IFR CLOUDS IN TAF.
A FAIRLY STRONG UPPER LEVEL DISTURBANCE AND REINFORCING SHOT OF
COOL AIR WILL MOVE ACROSS REGION DURING THE DAY ON FRIDAY...AND
THIS WILL RESULT IN RAIN SHOWERS SPREADING IN FROM NORTHWEST.
PREVAILING RAIN SHOWERS ARE EXPECTED IN ROCKFORD VICINITY DURING
AFTERNOON...BUT NOT UNTIL BEYOND THE 30 HOUR ORD TAF AT THE
EASTERN TAF SITES.
REGARDING WINDS...PREDOMINANTLY NORTHERLY WINDS EARLY THIS
AFTERNOON ARE EXPECTED TO SHIFT TO NORTHEAST OR NORTH-NORTHEAST
LATER THIS AFTERNOON INTO THE EVENING. IF AN ORGANIZED LAKE EFFECT
BAND SETS UP INTO NORTHEAST ILLINOIS OVERNIGHT...WINDS MAY TREND
MORE NORTHERLY OR EVEN NORTH-NORTHWEST...BUT THEN NORTHEAST WINDS
AROUND 10 KT ARE EXPECTED FRIDAY MORNING THROUGH THE END OF THE
PERIOD.
RC
//ORD AND MDW CONFIDENCE...UPDATED 20Z...
* MEDIUM-HIGH IN MVFR CIGS CONTINUING THROUGH THE PERIOD. LOW IN
IFR LATE TONIGHT INTO FRIDAY.
* MEDIUM IN WIND TRENDS THROUGH THE PERIOD. MEDIUM IN WIND SPEEDS
INTO THIS EVENING.
* MEDIUM-HIGH IN LAKE EFFECT SHOWERS DEVELOPING TONIGHT...LOW IN
DIRECT IMPACTS TO TERMINALS.
* MEDIUM IN PREVAILING RAIN SHOWERS MORE LIKELY TO MOVE IN FRIDAY
EVENING.
RC
//OUTLOOK FOR ORD/MDW FOR 00Z SATURDAY-12Z THURSDAY...UPDATED 12Z...
FRIDAY NIGHT...SHRA LIKELY. MVFR/IFR CIGS PSBL.
SATURDAY...VFR. GUSTY NW WINDS IN THE MORNING.
SUNDAY...VFR.
MONDAY...CHC SHRA DURING THE DAY. MVFR CIGS PSBL.
TUESDAY AND WEDNESDAY...VFR
KMD
&&
.MARINE...
209 PM CDT
STRONG LOW PRESSURE SYSTEM THAT BROUGHT THE GALE FORCE WINDS HAS
CONTINUED TO LIFT NORTHEAST AWAY FROM THE GREAT LAKES REGION...WITH
THE GRADIENT OVER LAKE MICHIGAN STEADILY WEAKENING. THE GRADIENT
WILL REMAIN JUST ENOUGH TO PRODUCE WINDS BETWEEN 15 AND 25 KT
OVERNIGHT GENERALLY FROM THE NORTH...BEGINNING TO TURN SLIGHTLY
NORTHEAST AHEAD OF THE BROAD RIDGE OF HIGH PRESSURE OVER THE CENTRAL
PLAINS THAT IS POISED TO ARRIVE SATURDAY INTO SUNDAY MORNING.
ANOTHER FRONTAL BOUNDARY WILL ARRIVE FRIDAY EVENING WHICH WILL
PROVIDE A REINFORCING PUSH OF GUSTY NORTH WINDS TO THE LAKE...WITH
THE GRADIENT BEING SLIGHTLY TIGHTER ALONG THE SOUTHERN HALF OF THE
LAKE FRIDAY NIGHT THROUGH EARLY SATURDAY. WAVES WILL REMAIN ELEVATED
THROUGH FRIDAY NIGHT...CREATING HAZARDOUS WAVES TO SMALL CRAFT
THROUGH THIS PERIOD. THEN THE WAVES SHOULD STEADILY DIMINISH BY
EARLY SATURDAY MORNING TO ALLOW THE SMALL CRAFT TO END. HOWEVER IF
THE WINDS REMAIN ELEVATED...THIS WILL KEEP WAVES UP AS WELL THROUGH
DAYBREAK SAT. HIGH PRESSURE IS THEN POISED TO BUILD OVER LAKE
MICHIGAN SATURDAY EVENING AND CONTINUE THROUGH SUNDAY. WHICH WILL
THEN PROVIDE MUCH LIGHTER WINDS AND SUBSIDING WAVES.
BEACHLER
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...BEACH HAZARDS STATEMENT...ILZ006-ILZ014 UNTIL 5 PM SATURDAY.
IN...BEACH HAZARDS STATEMENT...INZ001-INZ002 UNTIL 5 PM SATURDAY.
LM...SMALL CRAFT ADVISORY...NEARSHORE WATERS
UNTIL 10 PM FRIDAY.
&&
$$
VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
WWW.FACEBOOK.COM/US.NATIONALWEATHERSERVICE.CHICAGO.GOV
WWW.TWITTER.COM/NWSCHICAGO
WWW.YOUTUBE.COM/NWSCHICAGO
Area Forecast Discussion
NATIONAL WEATHER SERVICE LINCOLN IL
259 PM CDT Thu Sep 11 2014
.SHORT TERM...(Tonight)
ISSUED AT 259 PM CDT THU SEP 11 2014
Cold front just south of the Ohio River Valley this afternoon as
high pressure builds into the Midwest. Northerly flow at the sfc
bringing unseasonably cool temps into the region, in stark contrast
to the weather of the last few days. Cooler temperatures expected
to continue into the overnight hours. With lows dipping into the
upper 40s across the nrn portions of the state...and low 50s before
dawn for much of Illinois. Breaks in the cloud cover off to the
west not having much success in moving into the region. As a
result, continued cloud coverage expected through the overnight
hours as llvl RH has remained trapped. Both NAM and HRRR slow to
move clouds out, though some brief clearing is possible NW of the
Illinois River.
&&
.LONG TERM...(Friday through Thursday)
ISSUED AT 259 PM CDT THU SEP 11 2014
Cool and cloudy conditions are expected again Friday as low level
northerly flow continues with a strong capping inversion at around
850 mb. An upper level shortwave will be rapidly approaching from
the west. The axis of the shortwave expected to cross Illinois late
Friday evening to early Saturday morning...pushing another frontal
boundary through the region. Current model forecasts are fairly
consistent keeping precipitation with this feature mainly north of
I-72...and modest amounts around 0.10 inches or less. Have PoPs
beginning Friday afternoon west of I-55 as lift associated with the
approaching shortwave begins...then PoPs spread through most areas
I-55 northward Friday evening. The system moves rapidly east-
northeastward leaving a cool and dry weekend behind it...with highs
in the 60s and lows in the 40s...as high pressure settles over the
area.
The next chance for precipitation will be Monday as models
consistently track another broad trough through the midwest. Cool
dry northwesterly flow aloft is expected to follow for the remainder
of the week with little chance for any precipitation and below
normal temperatures continuing.
&&
.AVIATION...(For the 18Z TAFS through 18Z Friday afternoon)
ISSUED AT 1234 PM CDT THU SEP 11 2014
Not much in the way of a change in the forecast. MVFR continuing,
with some IFR conditions still possible today as cigs are right on
the cusp btwn two categories above and below 1kft. Some breaks in
the clouds are still well to the west and northwest. Models are
breaking between some drying out of the low levels and the NAM
holding on to the higher RH below 850mb. HRRR keeping MVFR through
the day with some breaks approaching PIA, but certainly not
predominant and will amend accordingly should the sun break
through. However, the HRRR going into the evening hours starts to
drop the cigs once again, with IFR very near. Not going that
pessimistic just yet, but not clearing the MVFR through the end of
the fcst pd. North/northeast winds throughout.
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...HJS
LONG TERM...ONTON
AVIATION...HJS
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
1255 PM CDT THU SEP 11 2014
.DISCUSSION...
339 AM CDT
WHAT A DIFFERENCE A DAY MAKES...AS THE FIRST REAL AUTUMN-LIKE
PUSH OF COOL AIR SPREADS INTO THE MIDWEST TODAY IN THE WAKE OF
YESTERDAYS COLD FRONT. MAIN FOCUS OF THE FORECAST ARE THESE MID
OCTOBER-LIKE TEMPERATURES OVER THE NEXT SEVERAL DAYS...A CHANCE OF
RAIN FRIDAY AND FRIDAY NIGHT...AND EVEN THE POTENTIAL FOR SOME
LAKE EFFECT RAIN SHOWERS AS OUR UNSEASONABLY COOL AIR SPREADS OVER
THE RELATIVELY WARM LAKE MICHIGAN WATERS.
DEEP SURFACE LOW PRESSURE WHICH MOVED ACROSS THE UPPER MIDWEST
WEDNESDAY WAS PULLING AWAY ACROSS SOUTHWESTERN QUEBEC PER EARLY
MORNING ANALYSIS...WITH THE TRAILING COLD FRONT PUSHING THROUGH THE
LOWER OHIO VALLEY. MUCH COOLER WAS SPREADING IN FROM THE NORTH AND
NORTHWEST...WITH UPSTREAM TEMPS IN THE MID-40S ACROSS MINNESOTA AND
WISCONSIN AND EVEN A FEW LOW-MID 30S NOTED UP IN THE MINNESOTA
ARROWHEAD. THIS COOL AIR MASS WILL CONTINUE TO SPREAD INTO THE GREAT
LAKES AND MIDWEST TODAY AS SPRAWLING CANADIAN HIGH PRESSURE MOVES
SLOWLY SOUTHEAST ACROSS THE NORTHERN PLAINS AND UPPER MIDWEST. IR
SATELLITE IMAGERY SHOWS EXTENSIVE LOW CLOUD SHIELD ACROSS MUCH OF
THE UPPER MIDWEST...AND WITH ONLY WEAK SUBSIDENCE NOTED IN MODEL
TIME HEIGHT SECTIONS IT APPEARS THAT CLOUD COVER WILL BE SLOW TO
ERODE IN PERSISTENT COOL ADVECTION REGIME TODAY. LOW LEVEL THERMAL
PROGS AND GUIDANCE NUMBERS ALL POINT TO HIGHS RANGING FROM AROUND 60
NEAR THE IL/WI BORDER TODAY...TO THE LOW-MID 60S FAR SOUTH IN EAST
CENTRAL IL. TO PUT THESE TEMPS INTO PERSPECTIVE...61 IS THE RECORD
LOW MAXIMUM TEMP FOR TODAY/SEPTEMBER 11 FOR CHICAGO...WHICH WOULD BE
NORMAL HIGH TEMPERATURE RANGE FOR MID-LATE OCTOBER. EXTENSIVE CLOUD
COVER AND A MODEST NORTH WIND WILL HELP KEEP TEMPS IN THE 40S
TONIGHT.
850 MB TEMPS LOWER TO ABOUT +2 OR +3 C TONIGHT...WITH SOUTHERN LAKE
MICHIGAN WATER TEMPERATURES IN THE LOW-MID 60S F. FORECAST SOUNDINGS
DEPICT A RISING INVERSION LEVEL TONIGHT INTO EARLY FRIDAY WHICH
WOULD SUPPORT LAKE-INDUCED INSTABILITY CLOUDS AND POSSIBLY SOME
LIGHT SPRINKLES OR SHOWERS...MAINLY LATE TONIGHT INTO EARLY FRIDAY
AS THE INVERSION HEIGHT INCREASES. LOW LEVEL WINDS TURN
NORTHEASTERLY DURING THIS TIME WHICH MAY BRING A FEW OF THESE LIGHT
SHOWERS INTO NORTHEAST IL.
A GREATER CHANCE OF RAIN THEN LOOKS TO DEVELOP ACROSS THE AREA
FRIDAY...AS THE STRONG DIGGING SHORT WAVE SEEN IN CURRENT WATER
VAPOR IMAGERY ACROSS THE NORTHERN ROCKIES APPROACHES. IMPRESSIVE
FORCING FOR VERTICAL MOTION DEVELOPS PER MODEL OMEGA/Q-VECTOR
CONVERGENCE FIELDS AS THIS WAVE PROPAGATES ALONG THE ELEVATED
BAROCLINIC ZONE ASSOCIATED WITH OUR RECENT LOW LEVEL COOL AIR
INTRUSION. STRONG HEIGHT FALLS AND STRENGTHENING UPPER JET CORE
DEVELOP ALOFT...WITH LOWER LEVEL FRONTOGENETIC FORCING ALSO
INCREASING ESPECIALLY FRIDAY AFTERNOON/NIGHT AS THE TROUGH NEARS.
GUIDANCE IN GOOD AGREEMENT IN DEVELOPING RAIN ACROSS NORTHWEST HALF
OF THE CWA FRIDAY...AND ACROSS THE REMAINDER OF THE FORECAST AREA
FRIDAY NIGHT WITH GENERALLY 0.15-0.25 INCHES OF QPF. SHARP MID-LEVEL
TROUGH AXIS PASSES TOWARD SUNRISE SATURDAY MORNING...WITH QUICK
SHUT-OFF OF PRECIPITATION EXPECTED GIVEN STRONG MID-LEVEL SUBSIDENCE
AND SHARPLY RISING HEIGHTS BEHIND THE SHORT WAVE. EXCEPTION MAY BE
ALONG THE LAKE AND INTO NORTHWEST INDIANA SATURDAY MORNING AS SOME
POTENTIAL FOR LAKE EFFECT SHOWERS WILL LINGER UNTIL SUBSIDENCE
INVERSION STRENGTHENS AND LOWERS ENOUGH TO LIMIT DEPTH OF
INSTABILITY OVER THE LAKE WATERS.
SURFACE HIGH PRESSURE RIDGE DEVELOPS ACROSS THE REGION IN THE WAKE
OF THE STRONG DEPARTING MID-LEVEL WAVE SATURDAY AFTERNOON AND NIGHT
WITH GOOD POTENTIAL FOR SCOURING OUT CLOUDS. CLEARING LIKELY TO BE
OCCURRING TOWARD SUNRISE SATURDAY FROM THE WEST WITH SOME NORTH WIND
LIKELY KEEPING TEMPS FROM BOTTOMING OUT...THOUGH SOME AREAS NOT FAR
WEST/NORTH OF THE CWA COULD SEE SATURDAY NIGHT/SUNDAY AM MINS IN
THE 30S. DESPITE THE RETURN OF SUNSHINE NOT MUCH CHANGE IN HIGH
TEMPERATURE IS EXPECTED SATURDAY WITH REINFORCING PUSH OF COOLER AIR
AHEAD OF THE HIGH OFFSETTING ANY GAINS FROM MORE SUNSHINE. TEMPS IN
THE LOW 60S/LOWS IN THE 40S EXPECTED SATURDAY AND SATURDAY NIGHT...
THOUGH THE PROSPECT FOR A FEW SUNDAY AM LOWS IN THE 30S CANT BE
RULED OUT WITH LIGHT WINDS AND POTENTIALLY CLEAR SKIES.
THE SURFACE HIGH PRESSURE RIDGE DRIFTS SOUTHEAST AND WEAK WARM
ADVECTION RETURNS ON SUNDAY. RELATIVELY MODEST GAINS IN TEMPS
EXPECTED HOWEVER WITH MAX TEMPS MODERATING ONLY TO THE 65-70 RANGE
INTO EARLY NEXT WEEK AS ANOTHER MID-LEVEL WAVE APPROACHES. NEXT
CHANCE OF RAIN ACCOMPANIES THIS SYSTEM ON MONDAY.
RATZER
&&
.CLIMATE...
915 AM CDT SEP 11 2014
AN UNSEASONABLY COOL AIR MASS OVER THE REGION INTO THE WEEKEND
COULD PUT SOME RECORD TEMPERATURES IN JEOPARDY AT CHICAGO AND
ROCKFORD. RECORD LOW MAX TEMPERATURES ARE MOST LIKELY TO BE
THREATENED.
RECORD LOW MAX TEMPERATURES SEPTEMBER 11-13
-------------------------------------------
SEPTEMBER 11 SEPTEMBER 12 SEPTEMBER 13
------------ ------------ ------------
CHICAGO 61/1940 53/1902 55/1880
ROCKFORD 55/1914 56/1943 55/1970
RC
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 18Z...
* MVFR CIGS THROUGH THE PERIOD...WITH POTENTIAL FOR IFR LATE
TONIGHT INTO FRIDAY MORNING.
* NORTH-NORTHEAST WINDS 350-020 DEG AROUND 10 KT BECOMING MORE
NORTHEAST 020-040 DEG AROUND 10 KT BY ABOUT 20Z.
* LAKE EFFECT SHOWERS LATE TONIGHT INTO FRIDAY MORNING.
* NORTH-NORTHEAST WINDS AROUND 10 KT BECOMING NORTHEAST ON FRIDAY.
* RAIN SHOWERS MOVING INTO AREA LATE FRIDAY AFTERNOON...WITH
PREVAILING RAIN AND CIG/VSBY IMPACTS MORE LIKELY FRIDAY EVE.
RC
//DISCUSSION...UPDATED 18Z...
UNSEASONABLY COOL AIR MASS OVER THE REGION IS RESULTING IN SEVERAL
CONCERNS THIS PERIOD. MOISTURE LOCKED UNDER INVERSION IS KEEPING
STRATUS DECK IN PLACE THIS AFTERNOON AND NOW EXPECT PRIMARILY MVFR
CIGS THROUGH THE PERIOD. THE COOL AIR MASS MOVING OVER THE MILD
LAKE WATERS WILL LIKELY RESULT IN THE DEVELOPMENT OF LAKE EFFECT
SHOWERS LATE TONIGHT INTO FRIDAY MORNING. HIGHER RESOLUTION
GUIDANCE HINTS THAT DECENT BAND COULD EVEN SET UP INTO NORTHWEST
INDIANA INITIALLY AND THEN GRADUALLY SHIFT NORTHEAST. HAVE MEDIUM
TO HIGH CONFIDENCE THAT THERE WILL BE SHOWERS AROUND...BUT LOW
CONFIDENCE IN DIRECT IMPACTS TO ORD/MDW/GYY...THUS HAVE CARRIED
VCSH MENTION. IF SHRA ARE MORE ORGANIZED AND DIRECTLY IMPACT
TERMINALS...THERE COULD BE IMPACTS TO VSBY.
ONSHORE FLOW IS EXPECTED TO ALSO RESULT IN LOWERING OF MVFR
CIGS AT EASTERN TERMINALS...WITH SOME GUIDANCE MEMBERS INDICATING
POTENTIAL FOR IFR. HAVE HINTED AT THIS WITH SCT IFR CLOUDS IN TAF.
A FAIRLY STRONG UPPER LEVEL DISTURBANCE AND REINFORCING SHOT OF
COOL AIR WILL MOVE ACROSS REGION DURING THE DAY ON FRIDAY...AND
THIS WILL RESULT IN RAIN SHOWERS SPREADING IN FROM NORTHWEST.
PREVAILING RAIN SHOWERS ARE EXPECTED IN ROCKFORD VICINITY DURING
AFTERNOON...BUT NOT UNTIL BEYOND THE 30 HOUR ORD TAF AT THE
EASTERN TAF SITES.
REGARDING WINDS...PREDOMINANTLY NORTHERLY WINDS EARLY THIS
AFTERNOON ARE EXPECTED TO SHIFT TO NORTHEAST OR NORTH-NORTHEAST
LATER THIS AFTERNOON INTO THE EVENING. IF AN ORGANIZED LAKE EFFECT
BAND SETS UP INTO NORTHEAST ILLINOIS OVERNIGHT...WINDS MAY TREND
MORE NORTHERLY OR EVEN NORTH-NORTHWEST...BUT THEN NORTHEAST WINDS
AROUND 10 KT ARE EXPECTED FRIDAY MORNING THROUGH THE END OF THE
PERIOD.
RC
//ORD AND MDW CONFIDENCE...UPDATED 18Z...
* MEDIUM-HIGH IN MVFR CIGS CONTINUING THROUGH THE PERIOD. LOW IN
IFR LATE TONIGHT INTO FRIDAY.
* MEDIUM IN WIND TRENDS THROUGH THE PERIOD. MEDIUM-HIGH IN SPEEDS
AROUND 10 KT WITH NORTH-NORTHEAST WINDS THIS AFTERNOON.
* MEDIUM-HIGH IN LAKE EFFECT SHOWERS DEVELOPING TONIGHT...LOW IN
DIRECT IMPACTS TO TERMINALS.
* MEDIUM IN PREVAILING RAIN SHOWERS MORE LIKELY TO MOVE IN FRIDAY
EVENING.
RC
//OUTLOOK FOR ORD/MDW FOR 00Z SATURDAY-12Z THURSDAY...UPDATED 12Z...
FRIDAY NIGHT...SHRA LIKELY. MVFR/IFR CIGS PSBL.
SATURDAY...VFR. GUSTY NW WINDS IN THE MORNING.
SUNDAY...VFR.
MONDAY...CHC SHRA DURING THE DAY. MVFR CIGS PSBL.
TUESDAY AND WEDNESDAY...VFR
KMD
&&
.MARINE...
356 AM CDT
STRONG EARLY FALL LOW PRESSURE SYSTEM HAS KICKED OUT TO THE
NORTHEAST EARLY THIS MORNING AND WILL CONTINUE ITS TREK NORTHEAST
THROUGH QUEBEC OVER THE COMING DAYS. THIS SYSTEM COMBINED WITH A
STRONG COLD FRONT HAS LED TO 40-45 KT GALES EARLY THIS MORNING...AND
IN SPITE OF THE BUOYS SHOWING A TREND DOWNWARD...STILL SEEING SHIP
OBS OF 40 KT ALONG THE WEST HALF OF LAKE.
AS THE LOW MOVES OUT OF THE AREA...THE LINGERING GRADIENT WILL
CONTINUE TO EASE...THUS GALE FORCE GUSTS SHOULD LARGELY BE DONE BY
LATE MORNING. ALSO...WITH HIGH PRESSURE BUILDING INTO THE
PLAINS...THIS WILL MAINTAIN A FETCH OF NORTHERLY WINDS DOWN THE LAKE
AND KEEP WAVES ELEVATED THROUGH THE REST OF THE WEEK.
A SECONDARY COLD FRONT WILL PASS THROUGH THE LAKE FRIDAY NIGHT AND
WILL REINFORCE THE GUSTY NORTHERLY WINDS ON THE SOUTHERN HALF OF THE
LAKE AS A WEAK LOW DEVELOPS AHEAD OF THE FRONT. AT THIS POINT WAVES
WOULD HAVE BEEN GRADUALLY SUBSIDING DUE TO A WEAKENING WIND
FIELD...SO THIS FRONT WILL REBUILD WAVES AGAIN...ESPECIALLY ALONG
THE INDIANA SHORELINE. THE HIGH WILL THEN BUILD OVERHEAD FOR THE
WEEKEND.
KMD
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...BEACH HAZARDS STATEMENT...ILZ006-ILZ014 UNTIL 5 PM SATURDAY.
IN...BEACH HAZARDS STATEMENT...INZ001-INZ002 UNTIL 5 PM SATURDAY.
LM...SMALL CRAFT ADVISORY...NEARSHORE WATERS
UNTIL 10 PM FRIDAY.
&&
$$
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Area Forecast Discussion
NATIONAL WEATHER SERVICE LINCOLN IL
1241 PM CDT Thu Sep 11 2014
.UPDATE...
ISSUED AT 1057 AM CDT THU SEP 11 2014
Northerly winds and cooler temperatures advecting into the area
this morning under cloudy skies. Very little clearing anticipated
today as any clearing on sat imagery is well off to the NW. Sun
may cause a few breaks in the clouds by later this
afternoon/evening. Forecast going well and no updates are
anticipated at this time.
&&
.SHORT TERM...(Today)
ISSUED AT 229 AM CDT THU SEP 11 2014
07z/1am surface analysis shows cold front settling southward toward
the Ohio River, with all its associated precip now south of the KILX
CWA. Behind the boundary, extensive low cloud cover is noted on IR
satellite imagery across Illinois northward into Wisconsin/Minnesota.
With northerly winds expected to prevail throughout the day, think
clouds will remain in place, especially given presence of very
strong inversion at around 900mb. Models have different opinions
concerning sky cover today, with MAV guidance indicating partial
clearing and MET keeping conditions overcast. Given current
satellite imagery and developing inversion, think the pessimistic
MET solution is the way to go. As a result, have increased sky
cover to go with a mostly cloudy forecast today. Have also lowered
high temps due to clouds and strong CAA, with readings only rising
into the lower to middle 60s.
&&
.LONG TERM...(Tonight through Wednesday)
ISSUED AT 229 AM CDT THU SEP 11 2014
Another unseasonably cool day is on tap for Friday as N/NE flow
continues and skies remain partly to mostly cloudy. 500mb trough
currently over the Northern Rockies will track southeastward,
with the trough axis passing through Illinois Friday night. As has
been advertised for the past several model runs, clouds and
perhaps a few showers will accompany the trough, although models
differ on how much precip may occur. NAM continues to be rather
aggressive with its QPF, while both the GFS and ECMWF are drier
and more diurnally driven. Given dry airmass in place ahead of
this feature, prefer the GFS/ECMWF consensus here. Have introduced
chance PoPs across the western half of the CWA Friday afternoon as
the wave approaches, but have dropped PoPs to just slights Friday
night as daytime instability diminishes and lapse rates become
less steep.
Once the Friday night trough passes, strong Canadian high pressure
will provide cool and dry conditions this weekend. Temperatures
will begin to slowly moderate through the period, with highs
reaching the upper 60s and lower 70s by Sunday. After that, the
next northern stream short-wave will arrive early next week, with
the 00z Sep 11 models now in better agreement concerning its
timing. With fairly robust wave arriving on Monday, think clouds
and scattered showers are a good bet. This feature will quickly
track off to the east, resulting in a return to dry weather for
Tuesday and Wednesday.
&&
.AVIATION...(For the 18Z TAFS through 18Z Friday afternoon)
ISSUED AT 1234 PM CDT THU SEP 11 2014
Not much in the way of a change in the forecast. MVFR continuing,
with some IFR conditions still possible today as cigs are right on
the cusp btwn two categories above and below 1kft. Some breaks in
the clouds are still well to the west and northwest. Models are
breaking between some drying out of the low levels and the NAM
holding on to the higher RH below 850mb. HRRR keeping MVFR through
the day with some breaks approaching PIA, but certainly not
predominant and will amend accordingly should the sun break
through. However, the HRRR going into the evening hours starts to
drop the cigs once again, with IFR very near. Not going that
pessimistic just yet, but not clearing the MVFR through the end of
the fcst pd. North/northeast winds throughout.
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...HJS
SHORT TERM...BARNES
LONG TERM...BARNES
AVIATION...HJS
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
250 PM CDT THU SEP 11 2014
...UPDATED LONG TERM SECTION...
.SHORT TERM...(THIS EVENING THROUGH FRIDAY)
ISSUED AT 157 PM CDT THU SEP 11 2014
STATUS LINGERING ACROSS MOST OF SOUTHWEST AND WESTERN KANSAS EARLY THIS
AFTERNOON HAS REDUCED THE CHANCE FOR SURFACE BASED CONVECTION LATE
TODAY. AT THIS TIME HOWEVER A FEW SCATTERED ELEVATED SHOWERS OR
EVEN AN ISOLATED THUNDERSTORM WILL STILL BE POSSIBLE THROUGH EARLY
EVENING ACROSS FAR WESTERN KANSAS, MAINLY WEST OF HIGHWAY 83. THIS
IS BASED ON THE MOISTURE AND WARM AIR ADVECTION FORECAST AROUND
THE 700MB LEVEL AND ELEVATED CAPE VALUES BETWEEN 00Z AND 03Z
FRIDAY FROM THE NAM AND ARW.
MODELS TODAY REMAINED IN GOOD AGREEMENT WITH A REINFORCEMENT OF
COLDER AIR CROSSING WESTERN KANSAS LATE TONIGHT AS A COLD DOME OF
HIGH PRESSURE, LOCATED OVER EASTERN MONTANA AT 12Z THURSDAY, MOVES
SOUTHEAST INTO EASTERN WYOMING AND WESTERN NEBRASKA BY 12Z FRIDAY.
AS THIS COLDER AIR INVADES WESTERN KANSAS....GUSTY NORTHEAST WINDS
WILL DEVELOP. BASED ON THE MEAN WINDS FROM THE SURFACE TO 0.5KM
WINDS, 925MB TO 850MB WINDS AND WITH 12Z NAM BUFR SOUNDINGS IT
APPEARS WIND SPEEDS WILL BRIEFLY APPROACH ADVISORY CRITERIA
BETWEEN 09Z AND 15Z FRIDAY WEST OF HIGHWAY 83. GIVEN THE COLD AIR
ADVECTION ADVERTISED BY THE NAM AND GFS THE TEMPERATURES OVERNIGHT
WILL CONTINUE TO FAVOR THE PREVIOUS FORECAST WHICH WAS A FEW
DEGREES BELOW THE COOLER GUIDANCE DESPITE THE CLOUD COVER
EXPECTED. LOWS TONIGHT ARE STILL EXPECTED TO RANGE FROM THE LOWER
40S TO NEAR 50 DEGREES.
WIDESPREAD RAINFALL WILL IMPROVE ACROSS ALL OF WESTERN KANSAS
LATER TONIGHT AND THEN CONTINUE THROUGH FRIDAY AS A MID LEVEL
BAROCLINIC ZONE AHEAD OF AN UPPER LEVEL TROUGH CROSSES THE CENTRAL
PLAINS. THE BETTER FORCING FOR THIS PRECIPITATION TONIGHT AND
FRIDAY WILL OCCUR ALONG A BAND OF 850MB TO 700MB FRONTOGENISIS
THAT WILL MOVE FROM WEST CENTRAL KANSAS AT 06Z FRIDAY TO SOUTH
CENTRAL KANSAS BETWEEN 15Z AND 18Z FRIDAY. AFTER 18Z THE
PRECIPITATION IS EXPECTED TO TAPER OFF FROM NORTHWEST TO SOUTHEAST
AS THE MID LEVEL BAROCLINIC ZONE MOVES INTO CENTRAL KANSAS AND
NORTHERN OKLAHOMA. THERE MAY ALSO BE SOME CLEARING NEAR THE
COLORADO BORDER LATE IN THE DAY FRIDAY AS SUBSIDENCE DEVELOPS
BEHIND THE UPPER LEVEL TROUGH THAT WILL BE CROSSING NEBRASKA AND
KANSAS DURING THE DAY ON FRIDAY. LITTLE DIURNAL CHANGE IN
TEMPERATURES WILL OCCUR ACROSS WESTERN KANSAS BETWEEN THURSDAY
NIGHT LOWS AND HIGHS FRIDAY AFTERNOON BASED ON CLOUD COVER AND
PRECIPITATION CHANCES THROUGH MUCH OF THE DAY. TAKING THIS INTO
ACCOUNT WILL STAY CLOSE TO THE LATEST GUIDANCE ACROSS PORTIONS
WESTERN KANSAS WHERE SOME BREAKS OF SUN WILL BE POSSIBLE LATE
FRIDAY. WILL UNDERCUT GUIDANCE FURTHER EAST.
.LONG TERM...(FRIDAY NIGHT THROUGH WEDNESDAY) ISSUED AT 318 AM
CDT THU SEP 11 2014
FRIDAY AND SATURDAY WILL BE RECOVERY DAYS FROM THE RELATIVELY COOL
AND CLOUDY CONDITIONS FROM THE PREVIOUS WAVE. THE WAVE WILL BE
EXITING THE REGION ON FRIDAY EVENING, LEAVING IN IT`S WAKE ZONAL
WINDS ALOFT AND INCREASINGLY COOL AND DRY BOUNDARY LAYER ON
SATURDAY. EARLY SATURDAY MORNING, TEMPERATURES WILL PROBABLY PLUMMET
INTO THE UPPER 30S IN SOME AREAS OF THE WEST CENTRAL AND CENTRAL
COUNTIES WHERE LIGHT WINDS LOW DEW POINTS AND CLEARING SKIES FAVOR
EFFICIENT LONGWAVE RADIATIONAL COOLING. HOWEVER TEMPERATURES WILL
STILL WARM AT THE SURFACE DUE TO INCREASED INSOLATION WITH
TEMPERATES RISING THROUGH THE 60S BY SATURDAY AFTERNOON, AND A
LARGER JUMP ON STRONGER SOUTHERLY /SOUTHWEST WINDS ON SUNDAY INTO
THE LOW TO MID 80S IN SOME AREAS.
BY SUNDAY NIGHT OR EARLY MONDAY ALL OF THE MODELS BEGIN TO SHOW THE
NEXT PV ANOMALY MOVING THROUGH THE FLOW ACROSS THE GREAT LAKE REGION
WITH A WEAK TROUGH/DEFORMATION ZONE EXTENDING SOUTH THROUGH THE
CENTRAL PLANS IN VICINITY OF CENTRAL KANSAS. POPS HAVE CONTINUED TO
BE CARRIED FOR THUNDERSTORM CHANCES IN THIS PERIOD AS THE GFS MODEL
SOUNDINGS DO APPEAR TO SUPPORT THE POTENTIAL WITH NEAR SATURATED
PROFILES NEAR THE LCL AND JUST BELOW LFC MONDAY. BEYOND THAT,
CONVECTION COULD ALSO OCCUR ANY GIVEN DAY AS WEAK SOUTHERLY 850 MB
MOISTURE TRANSPORT SIGNALS CONTINUE ACROSS THE HIGH PLAINS REGION
TUESDAY AND WEDNESDAY.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z FRIDAY AFTERNOON)
ISSUED AT 1208 PM CDT THU SEP 11 2014
BUFR SOUNDINGS AND HRRR BOTH IN GOOD AGREEMENT WITH IFR AND LIFR
CEILINGS GRADUALLY IMPROVING THROUGH THE EARLY AFTERNOON WITH A
BRIEF PERIOD OF VFR CONDITIONS DEVELOPING AT GCK AND DDC AFTER
21Z. CLOUD BASES WILL THEN LOWER ONCE AGAIN BACK INTO THE 700 TO
1500FT AGL LEVEL AFTER 00Z FRIDAY AS MORE HUMID AIR RETURNS TO
SOUTHWEST KANSAS. IN ADDITION TO THE LOWERING CEILINGS EARLY
TONIGHT PERIODS OF LIGHT RAIN AND/OR DRIZZLE CAN BE EXPECTED LATE
TONIGHT THROUGH EARLY FRIDAY. NORTHEASTERLY WINDS AT 15 TO 20
KNOTS THIS AFTERNOON WILL BECOME MORE NORTHERLY AFTER 06Z AND THEN
INCREASE TO 20 TO NEAR 25 KNOTS.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 46 53 40 65 / 90 80 0 0
GCK 43 50 38 67 / 90 80 0 0
EHA 42 51 43 71 / 90 80 0 0
LBL 47 54 42 69 / 90 80 0 0
HYS 42 52 38 64 / 90 80 0 0
P28 52 58 43 67 / 40 60 0 0
&&
.DDC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...BURGERT
LONG TERM...MR
AVIATION...BURGERT
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
200 PM CDT THU SEP 11 2014
...UPDATED SHORT TERM DISCUSSION...
.SHORT TERM...(THIS EVENING THROUGH FRIDAY)
ISSUED AT 157 PM CDT THU SEP 11 2014
STATUS LINGERING ACROSS MOST OF SOUTHWEST AND WESTERN KANSAS EARLY THIS
AFTERNOON HAS REDUCED THE CHANCE FOR SURFACE BASED CONVECTION LATE
TODAY. AT THIS TIME HOWEVER A FEW SCATTERED ELEVATED SHOWERS OR
EVEN AN ISOLATED THUNDERSTORM WILL STILL BE POSSIBLE THROUGH EARLY
EVENING ACROSS FAR WESTERN KANSAS, MAINLY WEST OF HIGHWAY 83. THIS
IS BASED ON THE MOISTURE AND WARM AIR ADVECTION FORECAST AROUND
THE 700MB LEVEL AND ELEVATED CAPE VALUES BETWEEN 00Z AND 03Z
FRIDAY FROM THE NAM AND ARW.
MODELS TODAY REMAINED IN GOOD AGREEMENT WITH A REINFORCEMENT OF
COLDER AIR CROSSING WESTERN KANSAS LATE TONIGHT AS A COLD DOME OF
HIGH PRESSURE, LOCATED OVER EASTERN MONTANA AT 12Z THURSDAY, MOVES
SOUTHEAST INTO EASTERN WYOMING AND WESTERN NEBRASKA BY 12Z FRIDAY.
AS THIS COLDER AIR INVADES WESTERN KANSAS....GUSTY NORTHEAST WINDS
WILL DEVELOP. BASED ON THE MEAN WINDS FROM THE SURFACE TO 0.5KM
WINDS, 925MB TO 850MB WINDS AND WITH 12Z NAM BUFR SOUNDINGS IT
APPEARS WIND SPEEDS WILL BRIEFLY APPROACH ADVISORY CRITERIA
BETWEEN 09Z AND 15Z FRIDAY WEST OF HIGHWAY 83. GIVEN THE COLD AIR
ADVECTION ADVERTISED BY THE NAM AND GFS THE TEMPERATURES OVERNIGHT
WILL CONTINUE TO FAVOR THE PREVIOUS FORECAST WHICH WAS A FEW
DEGREES BELOW THE COOLER GUIDANCE DESPITE THE CLOUD COVER
EXPECTED. LOWS TONIGHT ARE STILL EXPECTED TO RANGE FROM THE LOWER
40S TO NEAR 50 DEGREES.
WIDESPREAD RAINFALL WILL IMPROVE ACROSS ALL OF WESTERN KANSAS
LATER TONIGHT AND THEN CONTINUE THROUGH FRIDAY AS A MID LEVEL
BAROCLINIC ZONE AHEAD OF AN UPPER LEVEL TROUGH CROSSES THE CENTRAL
PLAINS. THE BETTER FORCING FOR THIS PRECIPITATION TONIGHT AND
FRIDAY WILL OCCUR ALONG A BAND OF 850MB TO 700MB FRONTOGENISIS
THAT WILL MOVE FROM WEST CENTRAL KANSAS AT 06Z FRIDAY TO SOUTH
CENTRAL KANSAS BETWEEN 15Z AND 18Z FRIDAY. AFTER 18Z THE
PRECIPITATION IS EXPECTED TO TAPER OFF FROM NORTHWEST TO SOUTHEAST
AS THE MID LEVEL BAROCLINIC ZONE MOVES INTO CENTRAL KANSAS AND
NORTHERN OKLAHOMA. THERE MAY ALSO BE SOME CLEARING NEAR THE
COLORADO BORDER LATE IN THE DAY FRIDAY AS SUBSIDENCE DEVELOPS
BEHIND THE UPPER LEVEL TROUGH THAT WILL BE CROSSING NEBRASKA AND
KANSAS DURING THE DAY ON FRIDAY. LITTLE DIURNAL CHANGE IN
TEMPERATURES WILL OCCUR ACROSS WESTERN KANSAS BETWEEN THURSDAY
NIGHT LOWS AND HIGHS FRIDAY AFTERNOON BASED ON CLOUD COVER AND
PRECIPITATION CHANCES THROUGH MUCH OF THE DAY. TAKING THIS INTO
ACCOUNT WILL STAY CLOSE TO THE LATEST GUIDANCE ACROSS PORTIONS
WESTERN KANSAS WHERE SOME BREAKS OF SUN WILL BE POSSIBLE LATE
FRIDAY. WILL UNDERCUT GUIDANCE FURTHER EAST.
.LONG TERM...(FRIDAY THROUGH WEDNESDAY)
ISSUED AT 318 AM CDT THU SEP 11 2014
FRIDAY WILL BE COOL AND MOIST, WITH LIGHT RAIN LIKELY.
FRIDAY WILL BE IN A POST FRONTAL REGIME, WITH COOL HIGH PRESSURE
BUILDING IN FROM THE NORTHWEST. THE SURFACE FLOW WILL BE UPSLOPE
WITH NORTHEAST TO EASTERLY WINDS AT 10 TO 20 MPH. CLOUDS WILL BE
THICKEST IN THE MORNING, BUT STILL PREVALENT IN THE AFTERNOON. MAX
TEMPS WILL GENERALLY BE IN THE 50S, BUT I ONLY EXPECT LIGHT RAIN
WITH 0.05 TO 0.10 INCH ACCUMULATION. THE HIGH PRESSURE WILL BEGIN
TO DOMINATE FRIDAY EVENING, LEADING TO CLEAR SKIES OVERNIGHT. THE
COOL AIR WILL FILTRATE IN FROM THE NORTHWEST, AND FROST MAY BE
POSSIBLE IN OUR EXTREME NORTHWESTERN COUNTIES OF TREGO, AND
NORTHERN LANE AND SCOTT COUNTIES SATURDAY MORNING. AS THAT TIME
FRAME APPROACHES, WE WILL NEED TO LOOK INTO A POSSIBLE WATCH OR
REFINE THE AREA WHERE FROST MAY OCCUR.
AFTER THE FALL-LIKE WEATHER ON FRIDAY, SATURDAY AND SUNDAY WILL
SHOW A GRADUAL WARM UP, WITH HIGHS REACHING THE MID 60S TO LOWER
70S ON SATURDAY, AND BOUNDING UPWARD TO THE UPPER 70S TO LOWER 80S
BY SUNDAY. A COLD FRONT WILL PLOW THROUGH TO THE SOUTHEAST ON
MONDAY AFTERNOON, BRINGING A CHANCE FOR THUNDERSTORMS TO OUR
SOUTHEAST-MOST ZONES, PRIMARILY IN PRATT AND BARBER COUNTIES. AN
UPPER LEVEL WAVE WILL COME THROUGH IN THE FLOW MONDAY NIGHT,
GIVING MOST OF THE CWA A 20 TO 30 PERCENT CHANCE FOR
THUNDERSTORMS. A LEE SIDE TROUGH WILL BE IN WESTERN KANSAS TUESDAY
AND WEDNESDAY, AND SLIGHT CHANCES FOR SHOWERS AND ISOLATED
THUNDERSTORMS WILL EXIST ACROSS MOST OF OUR FORECAST AREA, MAINLY
THE EAST.
WEDNESDAY WILL SEE A RETURN TO A WARM SOUTHWEST FLOW, AND HIGH
TEMPERATURES WILL RESPOND LIKEWISE WITH VALUES IN THE LOWER 80S
NORTH OF I-70 AND THE MIDDLE 80S SOUTHWEST A LINE FROM GARDEN CITY
TO DODGE CITY TO MEDICINE LODGE. WINDS THROUGH THE EXTENDED DO NOT
LOOK TOO STRONG, EXCEPT AHEAD OF THE FRONT ON MONDAY, AND THEN
AGAIN BEHIND THE FRONT ON TUESDAY.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z FRIDAY AFTERNOON)
ISSUED AT 1208 PM CDT THU SEP 11 2014
BUFR SOUNDINGS AND HRRR BOTH IN GOOD AGREEMENT WITH IFR AND LIFR
CEILINGS GRADUALLY IMPROVING THROUGH THE EARLY AFTERNOON WITH A
BRIEF PERIOD OF VFR CONDITIONS DEVELOPING AT GCK AND DDC AFTER
21Z. CLOUD BASES WILL THEN LOWER ONCE AGAIN BACK INTO THE 700 TO
1500FT AGL LEVEL AFTER 00Z FRIDAY AS MORE HUMID AIR RETURNS TO
SOUTHWEST KANSAS. IN ADDITION TO THE LOWERING CEILINGS EARLY
TONIGHT PERIODS OF LIGHT RAIN AND/OR DRIZZLE CAN BE EXPECTED LATE
TONIGHT THROUGH EARLY FRIDAY. NORTHEASTERLY WINDS AT 15 TO 20
KNOTS THIS AFTERNOON WILL BECOME MORE NORTHERLY AFTER 06Z AND THEN
INCREASE TO 20 TO NEAR 25 KNOTS.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 45 53 40 65 / 90 80 0 0
GCK 42 50 38 67 / 90 80 0 0
EHA 45 51 43 71 / 90 80 0 0
LBL 48 54 42 69 / 90 80 0 0
HYS 42 52 38 64 / 90 80 0 0
P28 50 58 43 67 / 40 60 0 0
&&
.DDC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...BURGERT
LONG TERM...BURKE
AVIATION...BURGERT
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
1212 PM CDT THU SEP 11 2014
...UPDATED SYNOPSIS AND AVIATION DISCUSSION...
.SYNOPSIS...
ISSUED AT 1208 PM CDT THU SEP 11 2014
AT 12Z THURSDAY A -28C 500MB LOW WAS LOCATED OVER WESTERN MONTANA
WITH A +100 KNOT 300MB JET EXTENDING FROM THE BASED OF THIS UPPER
LOW NEAR SOUTHERN IDAHO EASTWARD INTO SOUTH DAKOTA. A 700MB
BAROCLINIC ZONE STRETCHED FROM EASTERN IDAHO TO SOUTHEAST WYOMING
AND ACROSS CENTRAL NEBRASKA. THIS IS ALSO WHERE AN AREA OF HIGHER
850MB AND 700MB MOISTURE APPEARS TO BE LOCATED EARLIER THIS
MORNING. AN 850MB COLD FRONT WAS LOCATED FROM SOUTHEAST COLORADO
TO NORTH CENTRAL KANSAS WITH A MOISTURE UPSLOPE FLOW FROM THE
SURFACE TO THE 850MB LEVEL JUST NORTH OF THIS BOUNDARY. DODGE CITY
SOUNDINGS HAD THE DEPTH OF THIS LOW LEVEL MOISTURE AROUND 3000FT
AGL. A ENFORCEMENT OF COOLER AIR AT 850MB LEVEL APPEARS TO EXTEND
FROM SOUTHEAST WYOMING TO SOUTHERN IOWA. 850MB TEMPERATURES THIS
MORNING SOUTH OF THIS BOUNDARY RANGE FROM +8C AT TOPEKA TO +11C AT
DODGE CITY WHILE NORTH OF THIS BOUNDARY RAPID CITY REPORTED -2C
AND ABERDEEN REPORTED -1C.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 112 AM CDT THU SEP 11 2014
SHORT TERM MODELS INDICATE AN UPPER LEVEL SHORTWAVE TROUGH DIGGING
SOUTHEAST ACROSS THE NORTHERN ROCKIES TODAY AND PUSHING FURTHER
SOUTHEAST INTO THE WESTERN HIGH PLAINS TONIGHT SETTING UP PRECIP
CHANCES ACROSS NEBRASKA SOUTHWARD INTO PORTIONS OF WESTERN KANSAS.
AS THE SHORTWAVE APPROACHES THIS EVENING, A SERIES OF H5 VORT MAXIMA
WILL BEGIN TO EJECT EASTWARD OUT OF THE COLORADO ROCKIES INTO THE
HIGH PLAINS OF EASTERN COLORADO AND WESTERN KANSAS. MEANWHILE, AN
ATTENDANT COLD FRONT TO THE SHORTWAVE WILL BEGIN TO PUSH SOUTHWARD
ACROSS WESTERN KANSAS LATE THIS EVENING INTO EARLY FRIDAY MORNING.
OVERNIGHT, DYNAMIC SUPPORT ALOFT WILL BECOME MORE FAVORABLE AS THE
RIGHT FRONT ENTRANCE REGION TO A +90KT JET EXITING THE APPROACHING
TROUGH AXIS SHIFTS SOUTHWARD INTO WESTERN KANSAS. AS A RESULT, RAIN
CHANCES WILL INCREASE ACROSS WESTERN KANSAS THIS EVENING, SPREADING
SOUTH AND EAST ACROSS THE REGION OVERNIGHT. A FEW ISOLATED
THUNDERSTORMS WILL BE POSSIBLE ACROSS EXTREME SOUTHWEST KANSAS THIS
EVENING WHERE SOME INCREASED INSTABILITY AND MORE FAVORABLE VERTICAL
SHEAR PROFILES WILL EXIST IN A SOUTHEASTERLY UPSLOPE FLOW. HOWEVER,
NAM/GFS MODEL SOUNDINGS INDICATE LIMITED INSTABILITY WITH CAPE
VALUES REMAINING WELL UNDER 1000 J/KG. THIS WILL RESTRICT THE
POTENTIAL FOR SEVERE STORMS ACROSS SOUTHWEST KANSAS.
TEMPERATURES WILL BE WELL BELOW NORMAL TODAY AS COOLER AIR FILTERS
SOUTHWARD INTO WESTERN KANSAS AHEAD OF A BROAD SURFACE HIGH MOVING
SOUTHEASTWARD OUT OF THE NORTHERN ROCKIES INTO THE HIGH PLAINS OF
EASTERN WYOMING AND WESTERN NEBRASKA. THE NAM AND GFS SHOW H85
TEMPERATURES FALLING BELOW 10C ACROSS CENTRAL KANSAS NEAR THE I-70
CORRIDOR BY THIS AFTERNOON WITH THE MID TO UPPER TEENS(C) ACROSS
EXTREME SOUTHWEST KANSAS WITHIN A SOUTHEAST UPSLOPE FLOW.
ADDITIONALLY, HIGH TEMPERATURES MAY BE HINDERED TODAY DEPENDING ON
HOW FAR SOUTH LOW LEVEL STRATUS MOVING OUT OF NEBRASKA THIS
MORNING PUSHES INTO SOUTHWEST KANSAS, NOT TO MENTION HOW LONG IT
MAY LAST. THE HRRR SUGGESTS THE STRATUS DECK PERSISTING THROUGH AT
LEAST MID DAY, PARTICULARLY ACROSS CENTRAL KANSAS IN THE VICINITY
OF THE I-70 CORRIDOR. BECAUSE OF THIS, HIGHS MAY STRUGGLE TO REACH
THE 60S(F) IN CENTRAL KANSAS WITH THE LOWER TO MID 70S(F) POSSIBLE
CLOSER TO THE OKLAHOMA BORDER, ESPECIALLY IN EXTREME SOUTHWEST
KANSAS. A SECONDARY PUSH OF COLDER AIR BEHIND YET ANOTHER COLD
FRONT PUSHING ACROSS WESTERN KANSAS EARLY FRIDAY MORNING WILL
LIKELY DROP LOWS DOWN INTO THE 40S(F) ACROSS MUCH OF CENTRAL AND
SOUTHWEST KANSAS TONIGHT.
.LONG TERM...(FRIDAY THROUGH WEDNESDAY)
ISSUED AT 318 AM CDT THU SEP 11 2014
FRIDAY WILL BE COOL AND MOIST, WITH LIGHT RAIN LIKELY.
FRIDAY WILL BE IN A POST FRONTAL REGIME, WITH COOL HIGH PRESSURE
BUILDING IN FROM THE NORTHWEST. THE SURFACE FLOW WILL BE UPSLOPE
WITH NORTHEAST TO EASTERLY WINDS AT 10 TO 20 MPH. CLOUDS WILL BE
THICKEST IN THE MORNING, BUT STILL PREVALENT IN THE AFTERNOON. MAX
TEMPS WILL GENERALLY BE IN THE 50S, BUT I ONLY EXPECT LIGHT RAIN
WITH 0.05 TO 0.10 INCH ACCUMULATION. THE HIGH PRESSURE WILL BEGIN
TO DOMINATE FRIDAY EVENING, LEADING TO CLEAR SKIES OVERNIGHT. THE
COOL AIR WILL FILTRATE IN FROM THE NORTHWEST, AND FROST MAY BE
POSSIBLE IN OUR EXTREME NORTHWESTERN COUNTIES OF TREGO, AND
NORTHERN LANE AND SCOTT COUNTIES SATURDAY MORNING. AS THAT TIME
FRAME APPROACHES, WE WILL NEED TO LOOK INTO A POSSIBLE WATCH OR
REFINE THE AREA WHERE FROST MAY OCCUR.
AFTER THE FALL-LIKE WEATHER ON FRIDAY, SATURDAY AND SUNDAY WILL
SHOW A GRADUAL WARM UP, WITH HIGHS REACHING THE MID 60S TO LOWER
70S ON SATURDAY, AND BOUNDING UPWARD TO THE UPPER 70S TO LOWER 80S
BY SUNDAY. A COLD FRONT WILL PLOW THROUGH TO THE SOUTHEAST ON
MONDAY AFTERNOON, BRINGING A CHANCE FOR THUNDERSTORMS TO OUR
SOUTHEAST-MOST ZONES, PRIMARILY IN PRATT AND BARBER COUNTIES. AN
UPPER LEVEL WAVE WILL COME THROUGH IN THE FLOW MONDAY NIGHT,
GIVING MOST OF THE CWA A 20 TO 30 PERCENT CHANCE FOR
THUNDERSTORMS. A LEE SIDE TROUGH WILL BE IN WESTERN KANSAS TUESDAY
AND WEDNESDAY, AND SLIGHT CHANCES FOR SHOWERS AND ISOLATED
THUNDERSTORMS WILL EXIST ACROSS MOST OF OUR FORECAST AREA, MAINLY
THE EAST.
WEDNESDAY WILL SEE A RETURN TO A WARM SOUTHWEST FLOW, AND HIGH
TEMPERATURES WILL RESPOND LIKEWISE WITH VALUES IN THE LOWER 80S
NORTH OF I-70 AND THE MIDDLE 80S SOUTHWEST A LINE FROM GARDEN CITY
TO DODGE CITY TO MEDICINE LODGE. WINDS THROUGH THE EXTENDED DO NOT
LOOK TOO STRONG, EXCEPT AHEAD OF THE FRONT ON MONDAY, AND THEN
AGAIN BEHIND THE FRONT ON TUESDAY.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z FRIDAY AFTERNOON)
ISSUED AT 1208 PM CDT THU SEP 11 2014
BUFR SOUNDINGS AND HRRR BOTH IN GOOD AGREEMENT WITH IFR AND LIFR
CEILINGS GRADUALLY IMPROVING THROUGH THE EARLY AFTERNOON WITH A
BRIEF PERIOD OF VFR CONDITIONS DEVELOPING AT GCK AND DDC AFTER
21Z. CLOUD BASES WILL THEN LOWER ONCE AGAIN BACK INTO THE 700 TO
1500FT AGL LEVEL AFTER 00Z FRIDAY AS MORE HUMID AIR RETURNS TO
SOUTHWEST KANSAS. IN ADDITION TO THE LOWERING CEILINGS EARLY
TONIGHT PERIODS OF LIGHT RAIN AND/OR DRIZZLE CAN BE EXPECTED LATE
TONIGHT THROUGH EARLY FRIDAY. NORTHEASTERLY WINDS AT 15 TO 20
KNOTS THIS AFTERNOON WILL BECOME MORE NORTHERLY AFTER 06Z AND THEN
INCREASE TO 20 TO NEAR 25 KNOTS.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 60 45 53 40 / 0 90 80 0
GCK 59 42 50 38 / 10 90 80 0
EHA 69 45 51 43 / 20 90 90 0
LBL 65 48 54 42 / 10 90 80 0
HYS 58 42 52 38 / 10 90 80 0
P28 69 50 58 43 / 0 40 60 0
&&
.DDC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...BURGERT
SHORT TERM...JJOHNSON
LONG TERM...BURKE
AVIATION...BURGERT
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
607 AM CDT THU SEP 11 2014
...UPDATE FOR THE AVIATION DISCUSSION...
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 112 AM CDT THU SEP 11 2014
SHORT TERM MODELS INDICATE AN UPPER LEVEL SHORTWAVE TROUGH DIGGING
SOUTHEAST ACROSS THE NORTHERN ROCKIES TODAY AND PUSHING FURTHER
SOUTHEAST INTO THE WESTERN HIGH PLAINS TONIGHT SETTING UP PRECIP
CHANCES ACROSS NEBRASKA SOUTHWARD INTO PORTIONS OF WESTERN KANSAS.
AS THE SHORTWAVE APPROACHES THIS EVENING, A SERIES OF H5 VORT MAXIMA
WILL BEGIN TO EJECT EASTWARD OUT OF THE COLORADO ROCKIES INTO THE
HIGH PLAINS OF EASTERN COLORADO AND WESTERN KANSAS. MEANWHILE, AN
ATTENDANT COLD FRONT TO THE SHORTWAVE WILL BEGIN TO PUSH SOUTHWARD
ACROSS WESTERN KANSAS LATE THIS EVENING INTO EARLY FRIDAY MORNING.
OVERNIGHT, DYNAMIC SUPPORT ALOFT WILL BECOME MORE FAVORABLE AS THE
RIGHT FRONT ENTRANCE REGION TO A +90KT JET EXITING THE APPROACHING
TROUGH AXIS SHIFTS SOUTHWARD INTO WESTERN KANSAS. AS A RESULT, RAIN
CHANCES WILL INCREASE ACROSS WESTERN KANSAS THIS EVENING, SPREADING
SOUTH AND EAST ACROSS THE REGION OVERNIGHT. A FEW ISOLATED
THUNDERSTORMS WILL BE POSSIBLE ACROSS EXTREME SOUTHWEST KANSAS THIS
EVENING WHERE SOME INCREASED INSTABILITY AND MORE FAVORABLE VERTICAL
SHEAR PROFILES WILL EXIST IN A SOUTHEASTERLY UPSLOPE FLOW. HOWEVER,
NAM/GFS MODEL SOUNDINGS INDICATE LIMITED INSTABILITY WITH CAPE
VALUES REMAINING WELL UNDER 1000 J/KG. THIS WILL RESTRICT THE
POTENTIAL FOR SEVERE STORMS ACROSS SOUTHWEST KANSAS.
TEMPERATURES WILL BE WELL BELOW NORMAL TODAY AS COOLER AIR FILTERS
SOUTHWARD INTO WESTERN KANSAS AHEAD OF A BROAD SURFACE HIGH MOVING
SOUTHEASTWARD OUT OF THE NORTHERN ROCKIES INTO THE HIGH PLAINS OF
EASTERN WYOMING AND WESTERN NEBRASKA. THE NAM AND GFS SHOW H85
TEMPERATURES FALLING BELOW 10C ACROSS CENTRAL KANSAS NEAR THE I-70
CORRIDOR BY THIS AFTERNOON WITH THE MID TO UPPER TEENS(C) ACROSS
EXTREME SOUTHWEST KANSAS WITHIN A SOUTHEAST UPSLOPE FLOW.
ADDITIONALLY, HIGH TEMPERATURES MAY BE HINDERED TODAY DEPENDING ON
HOW FAR SOUTH LOW LEVEL STRATUS MOVING OUT OF NEBRASKA THIS
MORNING PUSHES INTO SOUTHWEST KANSAS, NOT TO MENTION HOW LONG IT
MAY LAST. THE HRRR SUGGESTS THE STRATUS DECK PERSISTING THROUGH AT
LEAST MID DAY, PARTICULARLY ACROSS CENTRAL KANSAS IN THE VICINITY
OF THE I-70 CORRIDOR. BECAUSE OF THIS, HIGHS MAY STRUGGLE TO REACH
THE 60S(F) IN CENTRAL KANSAS WITH THE LOWER TO MID 70S(F) POSSIBLE
CLOSER TO THE OKLAHOMA BORDER, ESPECIALLY IN EXTREME SOUTHWEST
KANSAS. A SECONDARY PUSH OF COLDER AIR BEHIND YET ANOTHER COLD
FRONT PUSHING ACROSS WESTERN KANSAS EARLY FRIDAY MORNING WILL
LIKELY DROP LOWS DOWN INTO THE 40S(F) ACROSS MUCH OF CENTRAL AND
SOUTHWEST KANSAS TONIGHT.
.LONG TERM...(FRIDAY THROUGH WEDNESDAY)
ISSUED AT 318 AM CDT THU SEP 11 2014
FRIDAY WILL BE COOL AND MOIST, WITH LIGHT RAIN LIKELY.
FRIDAY WILL BE IN A POST FRONTAL REGIME, WITH COOL HIGH PRESSURE
BUILDING IN FROM THE NORTHWEST. THE SURFACE FLOW WILL BE UPSLOPE
WITH NORTHEAST TO EASTERLY WINDS AT 10 TO 20 MPH. CLOUDS WILL BE
THICKEST IN THE MORNING, BUT STILL PREVALENT IN THE AFTERNOON. MAX
TEMPS WILL GENERALLY BE IN THE 50S, BUT I ONLY EXPECT LIGHT RAIN
WITH 0.05 TO 0.10 INCH ACCUMULATION. THE HIGH PRESSURE WILL BEGIN
TO DOMINATE FRIDAY EVENING, LEADING TO CLEAR SKIES OVERNIGHT. THE
COOL AIR WILL FILTRATE IN FROM THE NORTHWEST, AND FROST MAY BE
POSSIBLE IN OUR EXTREME NORTHWESTERN COUNTIES OF TREGO, AND
NORTHERN LANE AND SCOTT COUNTIES SATURDAY MORNING. AS THAT TIME
FRAME APPROACHES, WE WILL NEED TO LOOK INTO A POSSIBLE WATCH OR
REFINE THE AREA WHERE FROST MAY OCCUR.
AFTER THE FALL-LIKE WEATHER ON FRIDAY, SATURDAY AND SUNDAY WILL
SHOW A GRADUAL WARM UP, WITH HIGHS REACHING THE MID 60S TO LOWER
70S ON SATURDAY, AND BOUNDING UPWARD TO THE UPPER 70S TO LOWER 80S
BY SUNDAY. A COLD FRONT WILL PLOW THROUGH TO THE SOUTHEAST ON
MONDAY AFTERNOON, BRINGING A CHANCE FOR THUNDERSTORMS TO OUR
SOUTHEAST-MOST ZONES, PRIMARILY IN PRATT AND BARBER COUNTIES. AN
UPPER LEVEL WAVE WILL COME THROUGH IN THE FLOW MONDAY NIGHT,
GIVING MOST OF THE CWA A 20 TO 30 PERCENT CHANCE FOR
THUNDERSTORMS. A LEE SIDE TROUGH WILL BE IN WESTERN KANSAS TUESDAY
AND WEDNESDAY, AND SLIGHT CHANCES FOR SHOWERS AND ISOLATED
THUNDERSTORMS WILL EXIST ACROSS MOST OF OUR FORECAST AREA, MAINLY
THE EAST.
WEDNESDAY WILL SEE A RETURN TO A WARM SOUTHWEST FLOW, AND HIGH
TEMPERATURES WILL RESPOND LIKEWISE WITH VALUES IN THE LOWER 80S
NORTH OF I-70 AND THE MIDDLE 80S SOUTHWEST A LINE FROM GARDEN CITY
TO DODGE CITY TO MEDICINE LODGE. WINDS THROUGH THE EXTENDED DO NOT
LOOK TOO STRONG, EXCEPT AHEAD OF THE FRONT ON MONDAY, AND THEN
AGAIN BEHIND THE FRONT ON TUESDAY.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z FRIDAY MORNING)
ISSUED AT 603 AM CDT THU SEP 11 2014
SETTLING HIGH PRESSURE HAS RESULTED IN LIGHT UPSLOPE, EAST-
NORTHEASTERLY WINDS AT THE SURFACE. STRATUS CLOUDS AND SOME FOG
FORMED IN THE MOIST, UPSLOPE FLOW. IFR CONDITIONS WILL PREVAIL
UNTIL ABOUT NOON, THEN MFVR CIGS WITH VFR VSBYS ARE EXPECTED.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 65 45 53 40 / 10 70 70 0
GCK 65 42 50 38 / 10 70 70 0
EHA 75 45 51 43 / 20 80 70 0
LBL 72 48 54 42 / 10 70 70 0
HYS 58 42 52 38 / 10 70 70 0
P28 65 50 58 43 / 10 70 70 0
&&
.DDC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...JJOHNSON
LONG TERM...BURKE
AVIATION...BURKE
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
322 AM CDT THU SEP 11 2014
...UPDATED FOR THE LONG TERM...
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 112 AM CDT THU SEP 11 2014
SHORT TERM MODELS INDICATE AN UPPER LEVEL SHORTWAVE TROUGH DIGGING
SOUTHEAST ACROSS THE NORTHERN ROCKIES TODAY AND PUSHING FURTHER
SOUTHEAST INTO THE WESTERN HIGH PLAINS TONIGHT SETTING UP PRECIP
CHANCES ACROSS NEBRASKA SOUTHWARD INTO PORTIONS OF WESTERN KANSAS.
AS THE SHORTWAVE APPROACHES THIS EVENING, A SERIES OF H5 VORT MAXIMA
WILL BEGIN TO EJECT EASTWARD OUT OF THE COLORADO ROCKIES INTO THE
HIGH PLAINS OF EASTERN COLORADO AND WESTERN KANSAS. MEANWHILE, AN
ATTENDANT COLD FRONT TO THE SHORTWAVE WILL BEGIN TO PUSH SOUTHWARD
ACROSS WESTERN KANSAS LATE THIS EVENING INTO EARLY FRIDAY MORNING.
OVERNIGHT, DYNAMIC SUPPORT ALOFT WILL BECOME MORE FAVORABLE AS THE
RIGHT FRONT ENTRANCE REGION TO A +90KT JET EXITING THE APPROACHING
TROUGH AXIS SHIFTS SOUTHWARD INTO WESTERN KANSAS. AS A RESULT, RAIN
CHANCES WILL INCREASE ACROSS WESTERN KANSAS THIS EVENING, SPREADING
SOUTH AND EAST ACROSS THE REGION OVERNIGHT. A FEW ISOLATED
THUNDERSTORMS WILL BE POSSIBLE ACROSS EXTREME SOUTHWEST KANSAS THIS
EVENING WHERE SOME INCREASED INSTABILITY AND MORE FAVORABLE VERTICAL
SHEAR PROFILES WILL EXIST IN A SOUTHEASTERLY UPSLOPE FLOW. HOWEVER,
NAM/GFS MODEL SOUNDINGS INDICATE LIMITED INSTABILITY WITH CAPE
VALUES REMAINING WELL UNDER 1000 J/KG. THIS WILL RESTRICT THE
POTENTIAL FOR SEVERE STORMS ACROSS SOUTHWEST KANSAS.
TEMPERATURES WILL BE WELL BELOW NORMAL TODAY AS COOLER AIR FILTERS
SOUTHWARD INTO WESTERN KANSAS AHEAD OF A BROAD SURFACE HIGH MOVING
SOUTHEASTWARD OUT OF THE NORTHERN ROCKIES INTO THE HIGH PLAINS OF
EASTERN WYOMING AND WESTERN NEBRASKA. THE NAM AND GFS SHOW H85
TEMPERATURES FALLING BELOW 10C ACROSS CENTRAL KANSAS NEAR THE I-70
CORRIDOR BY THIS AFTERNOON WITH THE MID TO UPPER TEENS(C) ACROSS
EXTREME SOUTHWEST KANSAS WITHIN A SOUTHEAST UPSLOPE FLOW.
ADDITIONALLY, HIGH TEMPERATURES MAY BE HINDERED TODAY DEPENDING ON
HOW FAR SOUTH LOW LEVEL STRATUS MOVING OUT OF NEBRASKA THIS
MORNING PUSHES INTO SOUTHWEST KANSAS, NOT TO MENTION HOW LONG IT
MAY LAST. THE HRRR SUGGESTS THE STRATUS DECK PERSISTING THROUGH AT
LEAST MID DAY, PARTICULARLY ACROSS CENTRAL KANSAS IN THE VICINITY
OF THE I-70 CORRIDOR. BECAUSE OF THIS, HIGHS MAY STRUGGLE TO REACH
THE 60S(F) IN CENTRAL KANSAS WITH THE LOWER TO MID 70S(F) POSSIBLE
CLOSER TO THE OKLAHOMA BORDER, ESPECIALLY IN EXTREME SOUTHWEST
KANSAS. A SECONDARY PUSH OF COLDER AIR BEHIND YET ANOTHER COLD
FRONT PUSHING ACROSS WESTERN KANSAS EARLY FRIDAY MORNING WILL
LIKELY DROP LOWS DOWN INTO THE 40S(F) ACROSS MUCH OF CENTRAL AND
SOUTHWEST KANSAS TONIGHT.
.LONG TERM...(FRIDAY THROUGH WEDNESDAY)
ISSUED AT 318 AM CDT THU SEP 11 2014
FRIDAY WILL BE COOL AND MOIST, WITH LIGHT RAIN LIKELY.
FRIDAY WILL BE IN A POST FRONTAL REGIME, WITH COOL HIGH PRESSURE
BUILDING IN FROM THE NORTHWEST. THE SURFACE FLOW WILL BE UPSLOPE
WITH NORTHEAST TO EASTERLY WINDS AT 10 TO 20 MPH. CLOUDS WILL BE
THICKEST IN THE MORNING, BUT STILL PREVALENT IN THE AFTERNOON. MAX
TEMPS WILL GENERALLY BE IN THE 50S, BUT I ONLY EXPECT LIGHT RAIN
WITH 0.05 TO 0.10 INCH ACCUMULATION. THE HIGH PRESSURE WILL BEGIN
TO DOMINATE FRIDAY EVENING, LEADING TO CLEAR SKIES OVERNIGHT. THE
COOL AIR WILL FILTRATE IN FROM THE NORTHWEST, AND FROST MAY BE
POSSIBLE IN OUR EXTREME NORTHWESTERN COUNTIES OF TREGO, AND
NORTHERN LANE AND SCOTT COUNTIES SATURDAY MORNING. AS THAT TIME
FRAME APPROACHES, WE WILL NEED TO LOOK INTO A POSSIBLE WATCH OR
REFINE THE AREA WHERE FROST MAY OCCUR.
AFTER THE FALL-LIKE WEATHER ON FRIDAY, SATURDAY AND SUNDAY WILL
SHOW A GRADUAL WARM UP, WITH HIGHS REACHING THE MID 60S TO LOWER
70S ON SATURDAY, AND BOUNDING UPWARD TO THE UPPER 70S TO LOWER 80S
BY SUNDAY. A COLD FRONT WILL PLOW THROUGH TO THE SOUTHEAST ON
MONDAY AFTERNOON, BRINGING A CHANCE FOR THUNDERSTORMS TO OUR
SOUTHEAST-MOST ZONES, PRIMARILY IN PRATT AND BARBER COUNTIES. AN
UPPER LEVEL WAVE WILL COME THROUGH IN THE FLOW MONDAY NIGHT,
GIVING MOST OF THE CWA A 20 TO 30 PERCENT CHANCE FOR
THUNDERSTORMS. A LEE SIDE TROUGH WILL BE IN WESTERN KANSAS TUESDAY
AND WEDNESDAY, AND SLIGHT CHANCES FOR SHOWERS AND ISOLATED
THUNDERSTORMS WILL EXIST ACROSS MOST OF OUR FORECAST AREA, MAINLY
THE EAST.
WEDNESDAY WILL SEE A RETURN TO A WARM SOUTHWEST FLOW, AND HIGH
TEMPERATURES WILL RESPOND LIKEWISE WITH VALUES IN THE LOWER 80S
NORTH OF I-70 AND THE MIDDLE 80S SOUTHWEST A LINE FROM GARDEN CITY
TO DODGE CITY TO MEDICINE LODGE. WINDS THROUGH THE EXTENDED DO NOT
LOOK TOO STRONG, EXCEPT AHEAD OF THE FRONT ON MONDAY, AND THEN
AGAIN BEHIND THE FRONT ON TUESDAY.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z THURSDAY NIGHT)
ISSUED AT 1200 AM CDT THU SEP 11 2014
LOW LEVEL STRATUS ACROSS MUCH OF NEBRASKA IS EXPECTED TO SHIFT SOUTH-
SOUTHWEST INTO CENTRAL AND PORTIONS OF SOUTHWEST KANSAS EARLY
THIS MORNING DROPPING CIGS WELL DOWN INTO THE MVFR CATEGORY IN
THE VICINITY OF ALL TAF SITES. AS RELATIVE HUMIDITY INCREASES,
BRIEF PERIODS OF IFR CIGS MAY BE POSSIBLE TOWARD SUNRISE WITH CIGS
BEGINNING TO SLOWLY LIFT THROUGH THURSDAY AFTERNOON. LIGHT
NORTHEASTERLY WINDS WILL PERSIST ACROSS CENTRAL AND SOUTHWEST
KANSAS EARLY THIS MORNING AS SURFACE HIGH PRESSURE BEGINS TO
SHIFT SOUTHEAST ACROSS THE NORTHERN PLAINS. WINDS MAY BECOME MORE
EASTERLY DURING THE DAY THURSDAY AS THE SURFACE HIGH PUSHES
FURTHER SOUTHEAST INTO NEBRASKA.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 65 45 53 40 / 10 70 70 0
GCK 65 42 50 38 / 10 70 70 0
EHA 75 45 51 43 / 20 80 70 0
LBL 72 48 54 42 / 10 70 70 0
HYS 58 42 52 38 / 10 70 70 0
P28 65 50 58 43 / 10 70 70 0
&&
.DDC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...JJOHNSON
LONG TERM...BURKE
AVIATION...JJOHNSON
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
115 AM CDT THU SEP 11 2014
...UPDATE TO SHORT TERM...
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 112 AM CDT THU SEP 11 2014
SHORT TERM MODELS INDICATE AN UPPER LEVEL SHORTWAVE TROUGH DIGGING
SOUTHEAST ACROSS THE NORTHERN ROCKIES TODAY AND PUSHING FURTHER
SOUTHEAST INTO THE WESTERN HIGH PLAINS TONIGHT SETTING UP PRECIP
CHANCES ACROSS NEBRASKA SOUTHWARD INTO PORTIONS OF WESTERN KANSAS.
AS THE SHORTWAVE APPROACHES THIS EVENING, A SERIES OF H5 VORT MAXIMA
WILL BEGIN TO EJECT EASTWARD OUT OF THE COLORADO ROCKIES INTO THE
HIGH PLAINS OF EASTERN COLORADO AND WESTERN KANSAS. MEANWHILE, AN
ATTENDANT COLD FRONT TO THE SHORTWAVE WILL BEGIN TO PUSH SOUTHWARD
ACROSS WESTERN KANSAS LATE THIS EVENING INTO EARLY FRIDAY MORNING.
OVERNIGHT, DYNAMIC SUPPORT ALOFT WILL BECOME MORE FAVORABLE AS THE
RIGHT FRONT ENTRANCE REGION TO A +90KT JET EXITING THE APPROACHING
TROUGH AXIS SHIFTS SOUTHWARD INTO WESTERN KANSAS. AS A RESULT, RAIN
CHANCES WILL INCREASE ACROSS WESTERN KANSAS THIS EVENING, SPREADING
SOUTH AND EAST ACROSS THE REGION OVERNIGHT. A FEW ISOLATED
THUNDERSTORMS WILL BE POSSIBLE ACROSS EXTREME SOUTHWEST KANSAS THIS
EVENING WHERE SOME INCREASED INSTABILITY AND MORE FAVORABLE VERTICAL
SHEAR PROFILES WILL EXIST IN A SOUTHEASTERLY UPSLOPE FLOW. HOWEVER,
NAM/GFS MODEL SOUNDINGS INDICATE LIMITED INSTABILITY WITH CAPE
VALUES REMAINING WELL UNDER 1000 J/KG. THIS WILL RESTRICT THE
POTENTIAL FOR SEVERE STORMS ACROSS SOUTHWEST KANSAS.
TEMPERATURES WILL BE WELL BELOW NORMAL TODAY AS COOLER AIR FILTERS
SOUTHWARD INTO WESTERN KANSAS AHEAD OF A BROAD SURFACE HIGH MOVING
SOUTHEASTWARD OUT OF THE NORTHERN ROCKIES INTO THE HIGH PLAINS OF
EASTERN WYOMING AND WESTERN NEBRASKA. THE NAM AND GFS SHOW H85
TEMPERATURES FALLING BELOW 10C ACROSS CENTRAL KANSAS NEAR THE I-70
CORRIDOR BY THIS AFTERNOON WITH THE MID TO UPPER TEENS(C) ACROSS
EXTREME SOUTHWEST KANSAS WITHIN A SOUTHEAST UPSLOPE FLOW.
ADDITIONALLY, HIGH TEMPERATURES MAY BE HINDERED TODAY DEPENDING ON
HOW FAR SOUTH LOW LEVEL STRATUS MOVING OUT OF NEBRASKA THIS
MORNING PUSHES INTO SOUTHWEST KANSAS, NOT TO MENTION HOW LONG IT
MAY LAST. THE HRRR SUGGESTS THE STRATUS DECK PERSISTING THROUGH AT
LEAST MID DAY, PARTICULARLY ACROSS CENTRAL KANSAS IN THE VICINITY
OF THE I-70 CORRIDOR. BECAUSE OF THIS, HIGHS MAY STRUGGLE TO REACH
THE 60S(F) IN CENTRAL KANSAS WITH THE LOWER TO MID 70S(F) POSSIBLE
CLOSER TO THE OKLAHOMA BORDER, ESPECIALLY IN EXTREME SOUTHWEST
KANSAS. A SECONDARY PUSH OF COLDER AIR BEHIND YET ANOTHER COLD
FRONT PUSHING ACROSS WESTERN KANSAS EARLY FRIDAY MORNING WILL
LIKELY DROP LOWS DOWN INTO THE 40S(F) ACROSS MUCH OF CENTRAL AND
SOUTHWEST KANSAS TONIGHT.
.LONG TERM...(THURSDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 343 PM CDT WED SEP 10 2014
PRECIPITATION EPISODE THURSDAY NIGHT INTO THE FIRST HALF OF FRIDAY
APPEARS TO BE ON TRACK. THERE REALLY WAS NOT A MAJOR CHANGE IN THE
OVERALL THINKING REGARDING TIMING OF THE FRONT, PRECIPITATION,
ETC...BUT THERE WERE A COUPLE OF ADJUSTMENTS. FIRST, IT APPEARS
THAT MUCH OF THE PRECIPITATION INITIALLY ACROSS FAR WEST-CENTRAL AND
SOUTHWEST KANSAS WILL BE CONVECTIVE IN NATURE. INTENSE CYCLOGENESIS
DURING THE LATE DAY WILL ALLOW SURFACE MOISTURE TO DRAW NORTHWEST
INTO FAR SOUTHEASTERN COLORADO/ADJACENT FAR SOUTHWEST KANSAS. THE
NAM12 SHOWS A MESOSCALE AREA OF SURFACE-BASED CAPE AROUND 1000 J/KG,
HOWEVER ANY SURFACE BASED STORMS SHOULD QUICKLY BECOME ELEVATED
ABOVE A SURGING COLD AIRMASS FROM THE NORTH. EVENTUALLY, THE NATURE
OF PRECIPITATION (ESPECIALLY BY 06Z) WILL BECOME STRATIFORM, SO IN
THE GRIDS WE WILL CONTINUE TO CARRY "RAIN" AS THE PRECIPITATION
(INSTEAD OF SHOWERS/THUNDERSTORMS). AS FAR AS FRIDAY GOES, THE FIRST
HALF OF THE DAY WILL BE COMPOSED OF NORTH WINDS, LOW STRATUS, RAIN,
AND TEMPERATURES IN THE 40S FOR MUCH OF THE SOUTHWEST KANSAS REGION,
WHICH IS A STARK CHANGE TO SOME OF THE SUMMER WARMTH WE HAVE BEEN
SEEING. FRIDAY HIGHS WILL OCCUR AT MIDNIGHT WITH TEMPERATURES FROM
THE MID-UPPER 50S TO LOWER 60S. BY MID-MORNING, MOST EVERYONE WILL
BE IN THE MID TO UPPER 40S...WITH STEADY TEMPERATURES THROUGH EARLY
AFTERNOON. EVENTUALLY, CLOUDS WILL BREAK UP WITH SOME DIRECT
INSOLATION BEING REALIZED, HELPING OFFSET THE COLD ADVECTION AS
TEMPERATURES WARM INTO THE 50 TO 53F RANGE. SATURDAY MORNING WILL BE
RATHER CHILLY WITH NEAR-RECORD LOW TEMPERATURES FOR MOST LOCATIONS.
WE WILL BE GOING FOR LOWS OF 36F DOWN TO A SCOTT CITY TO WAKEENEY
LINE WITH UPPER 30S AS FAR SOUTH AS THE ARKANSAS RIVER. THE ECMWF IS
THE MOST AGGRESSIVE MODEL SHOWING THE CENTER OF A NEAR 1030MB HIGH
FROM SOUTHWEST KANSAS INTO SOUTHWEST IOWA AND NEARLY CALM WINDS. IT
LOOKS LIKE AN IDEAL RADIATIONAL COOLING NIGHT, PER THE ECMWF, AND IT
IS CERTAINLY CONCEIVABLE WE SEE MORE AREAS OF THE WEST-
CENTRAL/SOUTHWEST KANSAS REGION 36F OR EVEN COOLER YIELDING SOME
FROST.
WE WILL BEGIN TO WARM BACK UP OVER THE WEEKEND AS THE HIGH DEPARTS
AND THE LOW LEVEL AIRMASS MODIFIES. THE FORECAST IS DRY THROUGH LATE
SUNDAY, HOWEVER SUNDAY EVENING/NIGHT SOME WARM ADVECTION IN THE 800-
900MB LAYER MAY SUPPORT SOME NOCTURNAL SHOWERS/THUNDERSTORMS AND WE
WILL HAVE SOME 20 POPS IN CENTRAL/SOUTH CENTRAL KANSAS FOR THAT
POSSIBILITY. ANOTHER FRONTAL PASSAGE IS ANTICIPATED MONDAY WITH
COOLER AIR SETTLING BACK IN AS ANOTHER DECENT SHORTWAVE TROUGH MOVES
EAST-SOUTHEAST ACROSS THE NORTHERN PLAINS INTO THE UPPER MIDWEST
REGION. HIGHEST POPS (30 PERCENT) WILL BE MONDAY NIGHT WITHIN THE
BAROCLINIC ZONE 800-700MB. IT IS STILL PRETTY FAR AWAY IN THE
FORECAST, BUT TUESDAY HIGHS WILL LIKELY BE LOWERED IF SUCCESSIVE
GLOBAL SPECTRAL MODEL RUNS CONTINUE TO SHOW A FAIRLY DECENT FRONTAL
PASSAGE AS THE 12Z RUNS SHOWED TODAY.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z THURSDAY NIGHT)
ISSUED AT 1200 AM CDT THU SEP 11 2014
LOW LEVEL STRATUS ACROSS MUCH OF NEBRASKA IS EXPECTED TO SHIFT SOUTH-
SOUTHWEST INTO CENTRAL AND PORTIONS OF SOUTHWEST KANSAS EARLY
THIS MORNING DROPPING CIGS WELL DOWN INTO THE MVFR CATEGORY IN
THE VICINITY OF ALL TAF SITES. AS RELATIVE HUMIDITY INCREASES,
BRIEF PERIODS OF IFR CIGS MAY BE POSSIBLE TOWARD SUNRISE WITH CIGS
BEGINNING TO SLOWLY LIFT THROUGH THURSDAY AFTERNOON. LIGHT
NORTHEASTERLY WINDS WILL PERSIST ACROSS CENTRAL AND SOUTHWEST
KANSAS EARLY THIS MORNING AS SURFACE HIGH PRESSURE BEGINS TO
SHIFT SOUTHEAST ACROSS THE NORTHERN PLAINS. WINDS MAY BECOME MORE
EASTERLY DURING THE DAY THURSDAY AS THE SURFACE HIGH PUSHES
FURTHER SOUTHEAST INTO NEBRASKA.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 67 45 53 40 / 10 70 70 0
GCK 67 42 50 38 / 10 70 70 0
EHA 75 45 51 43 / 20 80 70 0
LBL 72 48 54 42 / 10 70 70 0
HYS 60 42 52 38 / 10 70 70 0
P28 72 50 58 43 / 10 70 70 0
&&
.DDC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...JJOHNSON
LONG TERM...UMSCHEID
AVIATION...JJOHNSON
AREA FORECAST DISCUSSION
NWS PADUCAH KY
837 PM CDT Fri Sep 12 2014
.UPDATE...
Issued at 836 PM CDT FRI SEP 12 2014
Advancement of a sheared shortwave vorticity axis coincident with
decent low level moisture in the 306-311K isentropic layer across
the WFO PAH forecast area. Improved condensation pressure
deficits and local pressure derivatives of up to 1
microbars/second are forecast to move across the Southeast
Missouri Delta, the Purchase Area and Pennyrile areas of West
Kentucky between 02z-10z per the NMM version of the 4km NAM-WRF,
the 13km RAP, and 3km HRRR guidance.
With this in mind, adjusted the gridded forecast to enhances some
area with a mixture of measurable PoP/Weather (very light rain)
and patchy/areas of trace precipitation (drizzle) overnight. There
may be a miss for some areas, but attempted to use the high
resolution guidance to focus on those areas from late evening to
the early morning hours on Saturday for rain chances.
To accommodate (non-diabatic) sensible weather changes with these
enhanced precipitation areas, minor tweaks to temperature,
dewpoint, and winds were also modified for the evening. Dry air
advection with time at the lower levels should limit any
measurable visibility restrictions due to the precipitation overnight.
Given the short temporal (time) and spatial (space) impacts of the
precipitation, these adjustments will show up more in the gridded
forecast (available through the point and click forecast on the
NWS Paducah web page) and tabular forecast versus the general text
forecast for specific forecast locations overnight.
&&
.SHORT TERM...(Tonight through Sunday night)
Issued at 250 PM CDT FRI SEP 12 2014
The upper-level storm system is currently moving eastward through
Minnesota, and the trough trails to the southwest into the central
Plains. Some light showers are trying to move northeast out of
central Arkansas and toward the four state region. The general
consensus of the 12Z guidance is that the precipitation will
dissipate before reaching our region. The lone exception appears
to be the NAM which drags some light showers or drizzle northeast
through the Pennyrile region of Kentucky in the late evening and
early morning hours. Decided to keep a slight chance of showers in
the far east in that time period, but kept the rest of the area
dry tonight. There has been an increase in drizzly echoes to the
south and southeast of KPAH in the last hour, so also added patchy
drizzle over the southern half of the forecast area through 06Z.
The models continue to indicate a rapid clearing trend late
tonight and Saturday morning, as the upper system passes by and
the surface high really begins to surge across the area. Some
locations may test record min max temperatures Saturday. The
record min max at KPAH today is going to be shattered, but
Saturday will be with full sunshine. Gusty north winds will make
it feel even cooler Saturday afternoon.
Surface high pressure will slowly settle over the region, and
winds over much of the area may drop to near calm. This will
likely lead to good radiational cooling, and with dewpoints well
into the 40s throughout the area, some record lows may be tested
Sunday morning. Some moderation is expected in both temperatures
and dewpoints Sunday, but guidance may be a bit aggressive with
those trends.
.LONG TERM...(Monday through Friday)
Issued at 250 PM CDT FRI SEP 12 2014
For the upcoming work week, the weather appears to be fairly quiet.
The only real challenge will be Monday-Tuesday when decisions have
to be made on the likelihood of rain with an incoming frontal
boundary. Lower level moisture will be lacking for much of Monday,
with the bulk of it to our northwest. Therefore, believe that much
of the area will be dry.
As we head into Monday night into Tuesday, low level moisture will
be increasing from the north and settle into the area. The 00Z ECMWF
stays the course of its past runs and shows the moisture blasting on
through here and exiting by Tuesday morning, not bringing us much of
anything in the way of precip. The GFS a slower solution and
indicates better chances for precip after midnight Monday night in
the northwestern half. This is also supported by a few members of
the GFS precip ensembles. However, the moisture is slow to move
through, so it is possible to see a few lingering showers into
Tuesday, but will leave mainly dry for now. After watching the
behavior of the last several runs of the GFS, it has definitely been
favoring this scenario, unlike the faster Euro.
Nevertheless, by Wednesday, high pressure will build in and
northwest flow aloft will take over...with no big signals of any
other systems to deal with for the rest of the week.
&&
.AVIATION...
Issued at 637 PM CDT FRI SEP 12 2014
With moisture still trapped below the inversion, IFR/MVFR cigs will
continue through 14-16Z, then VFR. Northerly winds AOB 10 knots
will continue through 14Z, then veer around to the north northeast
around 15Z at 10 knots with gusts up to 18-20 knots at KCGI/KPAH.
&&
.PAH WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
MO...NONE.
IN...NONE.
KY...NONE.
&&
$$
UPDATE...Smith
SHORT TERM...DRS
LONG TERM...CW
AVIATION...JP
AREA FORECAST DISCUSSION
NWS JACKSON KY
354 PM EDT THU SEP 11 2014
.UPDATE...
ISSUED AT 142 PM EDT THU SEP 11 2014
CONSIDERING APPARENT FRONTAL POSITION AND PRECIP TRENDS...HAVE
LOWERED POPS FOR THIS AFTERNOON NORTH OF KJKL. ALSO...OBSERVED TEMPS
HAVE SURPASSED PREVIOUS FORECAST HIGHS IN OUR SOUTHERN COUNTIES. WITH
DEVELOPMENT OF PRECIP...IT SHOULD NOT GET TOO MUCH WARMER THERE...BUT
FORECAST MAX TEMPS DID NEED TO BE RAISED.
UPDATE ISSUED AT 1014 AM EDT THU SEP 11 2014
MADE ADJUSTMENTS TO TIMING OF SOUTHWARD PROGRESSION OF HIGHER POPS
TODAY...BUT WITH LITTLE IMPACT ON THE GENERAL 12 HOUR OUTLOOK.
UPDATE ISSUED AT 645 AM EDT THU SEP 11 2014
MADE A FEW ADJUSTMENTS TO THE FORECAST GRIDS FOR EARLY THIS MORNING
BASED ON THE CURRENT RADAR TRENDS. DECIDED TO SLIGHTLY SPEED UP THE
EASTWARD PROGRESSION OF SHOWERS AND STORMS THIS MORNING PER LATEST
RADAR. BASED ON UPSTREAM SHOWER AND STORM FORMATION...AND THE STILL
SLOW EASTWARD MOVEMENT OF THE COLD FRONT...IT STILL APPEARS THAT
WIDESPREAD RAINFALL WILL OCCUR ACROSS EASTERN KENTUCKY THROUGH THIS
AFTERNOON. LOCALLY HEAVY RAINFALL...AND PERHAPS SOME ISOLATED
INSTANCES OF FLOODING...WILL STILL BE POSSIBLE AS NUMEROUS STORMS
WILL LIKELY MOVE ACROSS THE SAME LOCATIONS THROUGHOUT THE DAY.
&&
.SHORT TERM...(TODAY THROUGH FRIDAY)
ISSUED AT 323 AM EDT THU SEP 11 2014
THE MODELS WERE IN GOOD AGREEMENT WITH THE LARGE SCALE AND LOCAL
WEATHER PATTERN FOR THE FIRST 36 HOURS OF THE FORECAST. THE
NAM12...SREF...AND HRRR MODELS HAVE ALL HANDLED THE TIMING AND
EVOLUTION OF A LINE OF SHOWERS AND STORMS THAT IS CURRENTLY MOVING
ACROSS CENTRAL KENTUCKY AND SOUTHERN OHIO. THE NAM12 AND SREF SEEM TO
DO A BETTER JOB OF HANDLING THE EVOLUTION OF THIS LINE OF SHOWERS AND
STORMS AFTER SUNRISE TODAY THAN THE HRRR...SO THOSE TWO MODELS WERE
USED TO CREATE THE NEW FORECAST. THE MODELS SUGGEST A STRONG COLD
FRONT WILL MOVE ACROSS CENTRAL AND EASTERN KENTUCKY TODAY...WITH THE
BOUNDARY EXITING THE AREA LATE THIS AFTERNOON. WIDESPREAD SHOWERS AND
STORMS ARE EXPECTED TO CONTINUE FIRING ALONG AND JUST AHEAD OF THIS
FRONT...WITH THE PEAK IN ACTIVITY OCCURRING BETWEEN ROUGHLY NOON AND
5 PM. THE LATEST FORECAST SOUNDINGS CONTINUE TO SUPPORT THE POTENTIAL
FOR LOCALLY HEAVY RAINFALL...WITH PRECIPITABLE WATER VALUES OF AROUND
2 INCHES PERSISTING THROUGH THE OVERNIGHT HOURS. SOME OF THE STRONGER
THUNDERSTORMS COULD ALSO PRODUCE GUSTY WINDS...BUT LOCALLY HEAVY
RAINFALL WILL BE THE PRIMARY THREAT. THE RAIN CHANCES WILL NOT END
ONCE THE FRONT HAS PASSED BY US...HOWEVER. THE BOUNDARY IS EXPECTED
TO STALL ACROSS THE TENNESSEE VALLEY ON FRIDAY. WAVES OF LOW PRESSURE
ARE THEN PROGGED TO MIGRATE FROM WEST TO EAST ALONG THE FRONT. THESE
DISTURBANCES WILL BRING ENOUGH LIFT AND MOISTURE TO LOCATIONS SOUTH
OF THE MOUNTAIN PARKWAY TO PERHAPS FIRE OFF ISOLATED TO SCATTERED
RAIN SHOWERS LATE TONIGHT THROUGH THE END OF THE DAY ON FRIDAY.
ONCE THE FRONT MOVES THROUGH EARLY TONIGHT...AN UNSEASONABLY COOL
CANADIAN AIR MASS WILL SETTLE OVER THE AREA. THIS AIR MASS WILL BRING
FALL LIKE TEMPERATURES TO EASTERN KENTUCKY TONIGHT AND FRIDAY. THE
COOL WEATHER WILL FIRST BE EXPERIENCED LATE TONIGHT...AS WINDS SHIFT
TO THE NORTH AND THE COOL AIR FULLY INVADES THE REGION. TONIGHTS
LOWS ARE EXPECTED TO BOTTOM OUT IN THE LOW TO MID 60S FOR MOST
LOCATIONS. FOLKS ALONG AND NORTH OF THE I-64 CORRIDOR MAY SEE THE
MERCURY DIP INTO THE UPPER 50S BY FRIDAY MORNING. HIGH TEMPERATURES
ON FRIDAY WILL LIKELY ONLY CLIMB INTO THE LOW TO MID 70S ACROSS THE
AREA.
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 354 PM EDT THU SEP 11 2014
MID TERM MODELS ARE STILL IN GOOD AGREEMENT FOR THE UPPER LEVEL LONG
WAVE PATTERN. A CLOSED LOW WILL BE PASSING ALONG THE UPPER GREAT
LAKES AT THE START OF THE FORECAST PERIOD...QUICKLY MOVING EASTWARD
AND LOSING STRENGTH. MEANWHILE...AN UPPER LEVEL RIDGE ACROSS THE
SOUTHERN CONUS WILL KEEP A GOOD TRANSITION ZONE OVER THE OHIO RIVER
VALLEY WITH STRONG WRLY FLOW. THIS SHORTWAVE/CLOSED LOW WILL CAUSE A
DISTURBANCE AT THE SURFACE...WITH A STRONG AREA OF QVECTOR
CONVERGENCE EXPECTED TO MOVE ACROSS THE UPPER GREAT LAKES REGION AS
WELL BY THE START OF THE FORECAST PERIOD. KY WILL FIND ITSELF ON THE
SOUTHERN FRINGES OF THIS DISTURBANCE...EXITING AS WE HEAD INTO 12Z
SATURDAY. AS IT QUICKLY PUSHES OFF TO THE EAST DURING THE DAY...ANY
PRECIP CHANCES WILL CEASE ACROSS FAR SE KY BY LATE SAT AFTERNOON.
MODELS ARE CONTINUING TO SUPPORT A FASTER EXIT OF PRECIPITATION
COMPARED TO THAT OF PREVIOUS RUNS FOR DURING THE DAY SATURDAY. CUT
BACK POPS SLIGHTLY...WITH ALL RAIN EXITING KY BY 0Z SUNDAY. THE
BOUNDARY WILL BECOME STALLED OUT ONCE MORE TO OUR SOUTH...NEAR THE
ATLANTIC COAST. HOWEVER...WITH THE INFLUX OF MOISTURE FROM THE
ATLANTIC...DAYTIME INSTABILITY WILL HELP PRECIP CHANCES SPREAD
FARTHER NORTH...POSSIBLY MAKING IT TO THE FAR SE BORDER OF KY DURING
THE DAY SUNDAY. PREVIOUS FORECAST LEFT MENTION OF PRECIP OUT
ALONG THE BORDER. HOWEVER...LATEST MODEL RUNS ARE ALL IN VERY
GOOD AGREEMENT THAT POPS MOVE CLOSE ENOUGH TO OUR BORDER THAT
CONFIDENCE ERRED ON THE SIDE AT LEAST INCLUDING SOME SLIGHT CHANCE
POPS FOR THE HIGH TERRAIN ALONG THE TN/VA BORDER. THE SAME APPLIES
FOR DURING THE DAY MONDAY....ALTHOUGH MODELS ARE GOOD AGREEMENT OF
THE PRECIP SPREADING FARTHER INTO THE CWA DURING THE DAY AS THE
BOUNDARY SHIFTS SLIGHTLY NORTHWARD.
MEANWHILE MONDAY...ANOTHER SHORTWAVE WILL DEVELOP IN THE LONGWAVE
PATTERN...DROPPING HEIGHTS SLIGHTLY ACROSS EASTERN KY AND BRINGING
YET ANOTHER QUICK MOVING BUT WEAK SURFACE COLD FRONT THAT WILL SWEEP
THROUGH KY LATE MONDAY NIGHT. ONCE AGAIN...ERN KY WILL FIND ITSELF
ON THE SOUTHERN FRINGES OF THIS DISTURBANCE...BUT THE BOUNDARY
SHOULD INTERACT ENOUGH WITH THE ONGOING PRECIP IN THE SE TO KEEP
POPS GOING THROUGHOUT MOST OF THE NIGHT MONDAY NIGHT AS WELL. STRONG
SUBSIDENCE WILL MOVE IN BEHIND THE FRONTAL BOUNDARY...WITH POPS
QUICKLY TAPERING OFF BY EARLY TUESDAY. WIDESPREAD CLOUD COVER WILL
ALSO ACCOMPANY THIS SYSTEM...SLOWLY CLEARING THROUGHOUT THE DAY
TUESDAY. HIGH PRESSURE...ONCE IN CONTROL...SHOULD STAY FOR THE
REMAINDER OF THE FORECAST PERIOD...WITH EASTERN KY FINALLY EXPECTED
TO HAVE A BREAK FROM THE PRECIP FROM TUESDAY THROUGH THURSDAY.
OVERALL...STRONG ZONAL FLOW ACROSS KY WILL KEEP TEMPERATURES
MODERATED IN THE MID 70S THROUGH MUCH OF THE EXTENDED FORECAST.
OVERNIGHT LOWS WILL BE CLOUD DEPENDENT. FOR THOSE NIGHTS WHEN
CLEARING IS EXPECTED...LOWS COULD DROP DOWN INTO THE CHILLY LOW TO
MID 50S. AND WHEN THERE IS CLOUD COVER INVOLVED...AS IS THE CASE IN
THE SE FOR MUCH OF THE EXTENDED...UPPER 50S AND LOW 60S WILL BE
RANGE TO LOOK FOR.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z FRIDAY AFTERNOON)
ISSUED AT 1255 PM EDT THU SEP 11 2014
EARLY AFTERNOON CONDITIONS RANGED FROM VLIFR IN MANY LOCATIONS NEAR
AND NORTH OF I-64...TO VFR IN MOST PLACES NEAR THE TN AND VA BORDERS.
SHOWERS WERE OCCURRING AND BECOMING MORE NUMEROUS ALONG AND SOUTHEAST
OF A LINE FROM SOMERSET TO PAINTSVILLE.
DURING THE AFTERNOON...THE TREND OF INCREASING PRECIP SOUTH AND EAST
OF KJKL SHOULD CONTINUE...WITH A SLIGHT CHANCE FOR THUNDERSTORMS TOO.
MVFR AND IFR WILL SPREAD/DEVELOP SOUTHEASTWARD TO THE STATE LINE BY
ABOUT 00Z. MEANWHILE LOCATIONS NEAR/NORTH OF I-64 SHOULD SEE
IMPROVEMENT...WITH CEILINGS EVENTUALLY BREAKING UP TONIGHT AND
FRIDAY.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...HAL
SHORT TERM...AR
LONG TERM...JMW
AVIATION...HAL
AREA FORECAST DISCUSSION
NWS JACKSON KY
142 PM EDT THU SEP 11 2014
.UPDATE...
ISSUED AT 142 PM EDT THU SEP 11 2014
CONSIDERING APPARENT FRONTAL POSITION AND PRECIP TRENDS...HAVE
LOWERED POPS FOR THIS AFTERNOON NORTH OF KJKL. ALSO...OBSERVED TEMPS
HAVE SURPASSED PREVIOUS FORECAST HIGHS IN OUR SOUTHERN COUNTIES. WITH
DEVELOPMENT OF PRECIP...IT SHOULD NOT GET TOO MUCH WARMER THERE...BUT
FORECAST MAX TEMPS DID NEED TO BE RAISED.
UPDATE ISSUED AT 1014 AM EDT THU SEP 11 2014
MADE ADJUSTMENTS TO TIMING OF SOUTHWARD PROGRESSION OF HIGHER POPS
TODAY...BUT WITH LITTLE IMPACT ON THE GENERAL 12 HOUR OUTLOOK.
UPDATE ISSUED AT 645 AM EDT THU SEP 11 2014
MADE A FEW ADJUSTMENTS TO THE FORECAST GRIDS FOR EARLY THIS MORNING
BASED ON THE CURRENT RADAR TRENDS. DECIDED TO SLIGHTLY SPEED UP THE
EASTWARD PROGRESSION OF SHOWERS AND STORMS THIS MORNING PER LATEST
RADAR. BASED ON UPSTREAM SHOWER AND STORM FORMATION...AND THE STILL
SLOW EASTWARD MOVEMENT OF THE COLD FRONT...IT STILL APPEARS THAT
WIDESPREAD RAINFALL WILL OCCUR ACROSS EASTERN KENTUCKY THROUGH THIS
AFTERNOON. LOCALLY HEAVY RAINFALL...AND PERHAPS SOME ISOLATED
INSTANCES OF FLOODING...WILL STILL BE POSSIBLE AS NUMEROUS STORMS
WILL LIKELY MOVE ACROSS THE SAME LOCATIONS THROUGHOUT THE DAY.
&&
.SHORT TERM...(TODAY THROUGH FRIDAY)
ISSUED AT 323 AM EDT THU SEP 11 2014
THE MODELS WERE IN GOOD AGREEMENT WITH THE LARGE SCALE AND LOCAL
WEATHER PATTERN FOR THE FIRST 36 HOURS OF THE FORECAST. THE
NAM12...SREF...AND HRRR MODELS HAVE ALL HANDLED THE TIMING AND
EVOLUTION OF A LINE OF SHOWERS AND STORMS THAT IS CURRENTLY MOVING
ACROSS CENTRAL KENTUCKY AND SOUTHERN OHIO. THE NAM12 AND SREF SEEM TO
DO A BETTER JOB OF HANDLING THE EVOLUTION OF THIS LINE OF SHOWERS AND
STORMS AFTER SUNRISE TODAY THAN THE HRRR...SO THOSE TWO MODELS WERE
USED TO CREATE THE NEW FORECAST. THE MODELS SUGGEST A STRONG COLD
FRONT WILL MOVE ACROSS CENTRAL AND EASTERN KENTUCKY TODAY...WITH THE
BOUNDARY EXITING THE AREA LATE THIS AFTERNOON. WIDESPREAD SHOWERS AND
STORMS ARE EXPECTED TO CONTINUE FIRING ALONG AND JUST AHEAD OF THIS
FRONT...WITH THE PEAK IN ACTIVITY OCCURRING BETWEEN ROUGHLY NOON AND
5 PM. THE LATEST FORECAST SOUNDINGS CONTINUE TO SUPPORT THE POTENTIAL
FOR LOCALLY HEAVY RAINFALL...WITH PRECIPITABLE WATER VALUES OF AROUND
2 INCHES PERSISTING THROUGH THE OVERNIGHT HOURS. SOME OF THE STRONGER
THUNDERSTORMS COULD ALSO PRODUCE GUSTY WINDS...BUT LOCALLY HEAVY
RAINFALL WILL BE THE PRIMARY THREAT. THE RAIN CHANCES WILL NOT END
ONCE THE FRONT HAS PASSED BY US...HOWEVER. THE BOUNDARY IS EXPECTED
TO STALL ACROSS THE TENNESSEE VALLEY ON FRIDAY. WAVES OF LOW PRESSURE
ARE THEN PROGGED TO MIGRATE FROM WEST TO EAST ALONG THE FRONT. THESE
DISTURBANCES WILL BRING ENOUGH LIFT AND MOISTURE TO LOCATIONS SOUTH
OF THE MOUNTAIN PARKWAY TO PERHAPS FIRE OFF ISOLATED TO SCATTERED
RAIN SHOWERS LATE TONIGHT THROUGH THE END OF THE DAY ON FRIDAY.
ONCE THE FRONT MOVES THROUGH EARLY TONIGHT...AN UNSEASONABLY COOL
CANADIAN AIR MASS WILL SETTLE OVER THE AREA. THIS AIR MASS WILL BRING
FALL LIKE TEMPERATURES TO EASTERN KENTUCKY TONIGHT AND FRIDAY. THE
COOL WEATHER WILL FIRST BE EXPERIENCED LATE TONIGHT...AS WINDS SHIFT
TO THE NORTH AND THE COOL AIR FULLY INVADES THE REGION. TONIGHTS
LOWS ARE EXPECTED TO BOTTOM OUT IN THE LOW TO MID 60S FOR MOST
LOCATIONS. FOLKS ALONG AND NORTH OF THE I-64 CORRIDOR MAY SEE THE
MERCURY DIP INTO THE UPPER 50S BY FRIDAY MORNING. HIGH TEMPERATURES
ON FRIDAY WILL LIKELY ONLY CLIMB INTO THE LOW TO MID 70S ACROSS THE
AREA.
.LONG TERM...(FRIDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 431 AM EDT THU SEP 11 2014
THE MODELS ARE IN GOOD AGREEMENT WITH THE LONG WAVE PATTERN THROUGH
THE PERIOD. PROGRESSIVE AND AMPLIFIED FLOW WILL CONTROL ACROSS THE
NORTHERN HALF OF THE CONUS AS SEVERAL PASSING SHORT WAVES HELP TO
REINFORCE TROUGHING ACROSS THE REGION. UPPER LEVEL RIDGING HANGING ON
ACROSS THE SOUTHERN CONUS WILL GRADUALLY DAMPEN AND GET SUPPRESSED
FURTHER SOUTH INTO EARLY NEXT WEEK...BEFORE CONSOLIDATING MORE ACROSS
THE DESERT SOUTHWEST BY THE MIDDLE OF NEXT WEEK.
FOR EASTERN KENTUCKY...THE FIRST MAIN SHORT WAVE WILL MOVE THROUGH
FRIDAY NIGHT INTO SATURDAY...BRINGING A CHANCE OF SHOWERS. GENERALLY
DRY WEATHER CAN BE EXPECTED FROM SATURDAY NIGHT THROUGH SUNDAY
NIGHT...AS HIGH PRESSURE TEMPORARILY BUILDS IN AT THE SURFACE. A
DEEPER TROUGH AXIS...WITH SOME SURFACE DEVELOPMENT NOTED BY THE
MODELS...WILL THEN AFFECT THE AREA FROM MONDAY THROUGH
TUESDAY. THIS SYSTEM WILL BRING SOME RENEWED CHANCES OF
SHOWERS...ALTHOUGH THERE WILL NOT BE AS MUCH LOW LEVEL MOISTURE TO
WORK WITH...SO STUCK FAIRLY CLOSE TO THE BLENDED GUIDANCE ON THE
POPS. DRY WEATHER WILL ENSUE ONCE AGAIN THEREAFTER...AS SURFACE HIGH
PRESSURE BUILDS IN ACROSS THE OHIO VALLEY.
TEMPERATURES WILL AVERAGE BELOW NORMAL THROUGH THE PERIOD...WITH
HIGHS MAINLY IN THE LOW TO MID 70S AND LOWS IN THE 50S.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z FRIDAY AFTERNOON)
ISSUED AT 1255 PM EDT THU SEP 11 2014
EARLY AFTERNOON CONDITIONS RANGED FROM VLIFR IN MANY LOCATIONS NEAR
AND NORTH OF I-64...TO VFR IN MOST PLACES NEAR THE TN AND VA BORDERS.
SHOWERS WERE OCCURRING AND BECOMING MORE NUMEROUS ALONG AND SOUTHEAST
OF A LINE FROM SOMERSET TO PAINTSVILLE.
DURING THE AFTERNOON...THE TREND OF INCREASING PRECIP SOUTH AND EAST
OF KJKL SHOULD CONTINUE...WITH A SLIGHT CHANCE FOR THUNDERSTORMS TOO.
MVFR AND IFR WILL SPREAD/DEVELOP SOUTHEASTWARD TO THE STATE LINE BY
ABOUT 00Z. MEANWHILE LOCATIONS NEAR/NORTH OF I-64 SHOULD SEE
IMPROVEMENT...WITH CEILINGS EVENTUALLY BREAKING UP TONIGHT AND
FRIDAY.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...HAL
SHORT TERM...AR
LONG TERM...GEOGERIAN
AVIATION...HAL
AREA FORECAST DISCUSSION
NWS JACKSON KY
1255 PM EDT THU SEP 11 2014
.UPDATE...
ISSUED AT 1014 AM EDT THU SEP 11 2014
MADE ADJUSTMENTS TO TIMING OF SOUTHWARD PROGRESSION OF HIGHER POPS
TODAY...BUT WITH LITTLE IMPACT ON THE GENERAL 12 HOUR OUTLOOK.
UPDATE ISSUED AT 645 AM EDT THU SEP 11 2014
MADE A FEW ADJUSTMENTS TO THE FORECAST GRIDS FOR EARLY THIS MORNING
BASED ON THE CURRENT RADAR TRENDS. DECIDED TO SLIGHTLY SPEED UP THE
EASTWARD PROGRESSION OF SHOWERS AND STORMS THIS MORNING PER LATEST
RADAR. BASED ON UPSTREAM SHOWER AND STORM FORMATION...AND THE STILL
SLOW EASTWARD MOVEMENT OF THE COLD FRONT...IT STILL APPEARS THAT
WIDESPREAD RAINFALL WILL OCCUR ACROSS EASTERN KENTUCKY THROUGH THIS
AFTERNOON. LOCALLY HEAVY RAINFALL...AND PERHAPS SOME ISOLATED
INSTANCES OF FLOODING...WILL STILL BE POSSIBLE AS NUMEROUS STORMS
WILL LIKELY MOVE ACROSS THE SAME LOCATIONS THROUGHOUT THE DAY.
&&
.SHORT TERM...(TODAY THROUGH FRIDAY)
ISSUED AT 323 AM EDT THU SEP 11 2014
THE MODELS WERE IN GOOD AGREEMENT WITH THE LARGE SCALE AND LOCAL
WEATHER PATTERN FOR THE FIRST 36 HOURS OF THE FORECAST. THE
NAM12...SREF...AND HRRR MODELS HAVE ALL HANDLED THE TIMING AND
EVOLUTION OF A LINE OF SHOWERS AND STORMS THAT IS CURRENTLY MOVING
ACROSS CENTRAL KENTUCKY AND SOUTHERN OHIO. THE NAM12 AND SREF SEEM TO
DO A BETTER JOB OF HANDLING THE EVOLUTION OF THIS LINE OF SHOWERS AND
STORMS AFTER SUNRISE TODAY THAN THE HRRR...SO THOSE TWO MODELS WERE
USED TO CREATE THE NEW FORECAST. THE MODELS SUGGEST A STRONG COLD
FRONT WILL MOVE ACROSS CENTRAL AND EASTERN KENTUCKY TODAY...WITH THE
BOUNDARY EXITING THE AREA LATE THIS AFTERNOON. WIDESPREAD SHOWERS AND
STORMS ARE EXPECTED TO CONTINUE FIRING ALONG AND JUST AHEAD OF THIS
FRONT...WITH THE PEAK IN ACTIVITY OCCURRING BETWEEN ROUGHLY NOON AND
5 PM. THE LATEST FORECAST SOUNDINGS CONTINUE TO SUPPORT THE POTENTIAL
FOR LOCALLY HEAVY RAINFALL...WITH PRECIPITABLE WATER VALUES OF AROUND
2 INCHES PERSISTING THROUGH THE OVERNIGHT HOURS. SOME OF THE STRONGER
THUNDERSTORMS COULD ALSO PRODUCE GUSTY WINDS...BUT LOCALLY HEAVY
RAINFALL WILL BE THE PRIMARY THREAT. THE RAIN CHANCES WILL NOT END
ONCE THE FRONT HAS PASSED BY US...HOWEVER. THE BOUNDARY IS EXPECTED
TO STALL ACROSS THE TENNESSEE VALLEY ON FRIDAY. WAVES OF LOW PRESSURE
ARE THEN PROGGED TO MIGRATE FROM WEST TO EAST ALONG THE FRONT. THESE
DISTURBANCES WILL BRING ENOUGH LIFT AND MOISTURE TO LOCATIONS SOUTH
OF THE MOUNTAIN PARKWAY TO PERHAPS FIRE OFF ISOLATED TO SCATTERED
RAIN SHOWERS LATE TONIGHT THROUGH THE END OF THE DAY ON FRIDAY.
ONCE THE FRONT MOVES THROUGH EARLY TONIGHT...AN UNSEASONABLY COOL
CANADIAN AIR MASS WILL SETTLE OVER THE AREA. THIS AIR MASS WILL BRING
FALL LIKE TEMPERATURES TO EASTERN KENTUCKY TONIGHT AND FRIDAY. THE
COOL WEATHER WILL FIRST BE EXPERIENCED LATE TONIGHT...AS WINDS SHIFT
TO THE NORTH AND THE COOL AIR FULLY INVADES THE REGION. TONIGHTS
LOWS ARE EXPECTED TO BOTTOM OUT IN THE LOW TO MID 60S FOR MOST
LOCATIONS. FOLKS ALONG AND NORTH OF THE I-64 CORRIDOR MAY SEE THE
MERCURY DIP INTO THE UPPER 50S BY FRIDAY MORNING. HIGH TEMPERATURES
ON FRIDAY WILL LIKELY ONLY CLIMB INTO THE LOW TO MID 70S ACROSS THE
AREA.
.LONG TERM...(FRIDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 431 AM EDT THU SEP 11 2014
THE MODELS ARE IN GOOD AGREEMENT WITH THE LONG WAVE PATTERN THROUGH
THE PERIOD. PROGRESSIVE AND AMPLIFIED FLOW WILL CONTROL ACROSS THE
NORTHERN HALF OF THE CONUS AS SEVERAL PASSING SHORT WAVES HELP TO
REINFORCE TROUGHING ACROSS THE REGION. UPPER LEVEL RIDGING HANGING ON
ACROSS THE SOUTHERN CONUS WILL GRADUALLY DAMPEN AND GET SUPPRESSED
FURTHER SOUTH INTO EARLY NEXT WEEK...BEFORE CONSOLIDATING MORE ACROSS
THE DESERT SOUTHWEST BY THE MIDDLE OF NEXT WEEK.
FOR EASTERN KENTUCKY...THE FIRST MAIN SHORT WAVE WILL MOVE THROUGH
FRIDAY NIGHT INTO SATURDAY...BRINGING A CHANCE OF SHOWERS. GENERALLY
DRY WEATHER CAN BE EXPECTED FROM SATURDAY NIGHT THROUGH SUNDAY
NIGHT...AS HIGH PRESSURE TEMPORARILY BUILDS IN AT THE SURFACE. A
DEEPER TROUGH AXIS...WITH SOME SURFACE DEVELOPMENT NOTED BY THE
MODELS...WILL THEN AFFECT THE AREA FROM MONDAY THROUGH
TUESDAY. THIS SYSTEM WILL BRING SOME RENEWED CHANCES OF
SHOWERS...ALTHOUGH THERE WILL NOT BE AS MUCH LOW LEVEL MOISTURE TO
WORK WITH...SO STUCK FAIRLY CLOSE TO THE BLENDED GUIDANCE ON THE
POPS. DRY WEATHER WILL ENSUE ONCE AGAIN THEREAFTER...AS SURFACE HIGH
PRESSURE BUILDS IN ACROSS THE OHIO VALLEY.
TEMPERATURES WILL AVERAGE BELOW NORMAL THROUGH THE PERIOD...WITH
HIGHS MAINLY IN THE LOW TO MID 70S AND LOWS IN THE 50S.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z FRIDAY AFTERNOON)
ISSUED AT 1255 PM EDT THU SEP 11 2014
EARLY AFTERNOON CONDITIONS RANGED FROM VLIFR IN MANY LOCATIONS NEAR
AND NORTH OF I-64...TO VFR IN MOST PLACES NEAR THE TN AND VA BORDERS.
SHOWERS WERE OCCURRING AND BECOMING MORE NUMEROUS ALONG AND SOUTHEAST
OF A LINE FROM SOMERSET TO PAINTSVILLE.
DURING THE AFTERNOON...THE TREND OF INCREASING PRECIP SOUTH AND EAST
OF KJKL SHOULD CONTINUE...WITH A SLIGHT CHANCE FOR THUNDERSTORMS TOO.
MVFR AND IFR WILL SPREAD/DEVELOP SOUTHEASTWARD TO THE STATE LINE BY
ABOUT 00Z. MEANWHILE LOCATIONS NEAR/NORTH OF I-64 SHOULD SEE
IMPROVEMENT...WITH CEILINGS EVENTUALLY BREAKING UP TONIGHT AND
FRIDAY.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...HAL
SHORT TERM...AR
LONG TERM...GEOGERIAN
AVIATION...HAL
AREA FORECAST DISCUSSION
NWS JACKSON KY
1014 AM EDT THU SEP 11 2014
.UPDATE...
ISSUED AT 1014 AM EDT THU SEP 11 2014
MADE ADJUSTMENTS TO TIMING OF SOUTHWARD PROGRESSION OF HIGHER POPS
TODAY...BUT WITH LITTLE IMPACT ON THE GENERAL 12 HOUR OUTLOOK.
UPDATE ISSUED AT 645 AM EDT THU SEP 11 2014
MADE A FEW ADJUSTMENTS TO THE FORECAST GRIDS FOR EARLY THIS MORNING
BASED ON THE CURRENT RADAR TRENDS. DECIDED TO SLIGHTLY SPEED UP THE
EASTWARD PROGRESSION OF SHOWERS AND STORMS THIS MORNING PER LATEST
RADAR. BASED ON UPSTREAM SHOWER AND STORM FORMATION...AND THE STILL
SLOW EASTWARD MOVEMENT OF THE COLD FRONT...IT STILL APPEARS THAT
WIDESPREAD RAINFALL WILL OCCUR ACROSS EASTERN KENTUCKY THROUGH THIS
AFTERNOON. LOCALLY HEAVY RAINFALL...AND PERHAPS SOME ISOLATED
INSTANCES OF FLOODING...WILL STILL BE POSSIBLE AS NUMEROUS STORMS
WILL LIKELY MOVE ACROSS THE SAME LOCATIONS THROUGHOUT THE DAY.
&&
.SHORT TERM...(TODAY THROUGH FRIDAY)
ISSUED AT 323 AM EDT THU SEP 11 2014
THE MODELS WERE IN GOOD AGREEMENT WITH THE LARGE SCALE AND LOCAL
WEATHER PATTERN FOR THE FIRST 36 HOURS OF THE FORECAST. THE
NAM12...SREF...AND HRRR MODELS HAVE ALL HANDLED THE TIMING AND
EVOLUTION OF A LINE OF SHOWERS AND STORMS THAT IS CURRENTLY MOVING
ACROSS CENTRAL KENTUCKY AND SOUTHERN OHIO. THE NAM12 AND SREF SEEM TO
DO A BETTER JOB OF HANDLING THE EVOLUTION OF THIS LINE OF SHOWERS AND
STORMS AFTER SUNRISE TODAY THAN THE HRRR...SO THOSE TWO MODELS WERE
USED TO CREATE THE NEW FORECAST. THE MODELS SUGGEST A STRONG COLD
FRONT WILL MOVE ACROSS CENTRAL AND EASTERN KENTUCKY TODAY...WITH THE
BOUNDARY EXITING THE AREA LATE THIS AFTERNOON. WIDESPREAD SHOWERS AND
STORMS ARE EXPECTED TO CONTINUE FIRING ALONG AND JUST AHEAD OF THIS
FRONT...WITH THE PEAK IN ACTIVITY OCCURRING BETWEEN ROUGHLY NOON AND
5 PM. THE LATEST FORECAST SOUNDINGS CONTINUE TO SUPPORT THE POTENTIAL
FOR LOCALLY HEAVY RAINFALL...WITH PRECIPITABLE WATER VALUES OF AROUND
2 INCHES PERSISTING THROUGH THE OVERNIGHT HOURS. SOME OF THE STRONGER
THUNDERSTORMS COULD ALSO PRODUCE GUSTY WINDS...BUT LOCALLY HEAVY
RAINFALL WILL BE THE PRIMARY THREAT. THE RAIN CHANCES WILL NOT END
ONCE THE FRONT HAS PASSED BY US...HOWEVER. THE BOUNDARY IS EXPECTED
TO STALL ACROSS THE TENNESSEE VALLEY ON FRIDAY. WAVES OF LOW PRESSURE
ARE THEN PROGGED TO MIGRATE FROM WEST TO EAST ALONG THE FRONT. THESE
DISTURBANCES WILL BRING ENOUGH LIFT AND MOISTURE TO LOCATIONS SOUTH
OF THE MOUNTAIN PARKWAY TO PERHAPS FIRE OFF ISOLATED TO SCATTERED
RAIN SHOWERS LATE TONIGHT THROUGH THE END OF THE DAY ON FRIDAY.
ONCE THE FRONT MOVES THROUGH EARLY TONIGHT...AN UNSEASONABLY COOL
CANADIAN AIR MASS WILL SETTLE OVER THE AREA. THIS AIR MASS WILL BRING
FALL LIKE TEMPERATURES TO EASTERN KENTUCKY TONIGHT AND FRIDAY. THE
COOL WEATHER WILL FIRST BE EXPERIENCED LATE TONIGHT...AS WINDS SHIFT
TO THE NORTH AND THE COOL AIR FULLY INVADES THE REGION. TONIGHTS
LOWS ARE EXPECTED TO BOTTOM OUT IN THE LOW TO MID 60S FOR MOST
LOCATIONS. FOLKS ALONG AND NORTH OF THE I-64 CORRIDOR MAY SEE THE
MERCURY DIP INTO THE UPPER 50S BY FRIDAY MORNING. HIGH TEMPERATURES
ON FRIDAY WILL LIKELY ONLY CLIMB INTO THE LOW TO MID 70S ACROSS THE
AREA.
.LONG TERM...(FRIDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 431 AM EDT THU SEP 11 2014
THE MODELS ARE IN GOOD AGREEMENT WITH THE LONG WAVE PATTERN THROUGH
THE PERIOD. PROGRESSIVE AND AMPLIFIED FLOW WILL CONTROL ACROSS THE
NORTHERN HALF OF THE CONUS AS SEVERAL PASSING SHORT WAVES HELP TO
REINFORCE TROUGHING ACROSS THE REGION. UPPER LEVEL RIDGING HANGING ON
ACROSS THE SOUTHERN CONUS WILL GRADUALLY DAMPEN AND GET SUPPRESSED
FURTHER SOUTH INTO EARLY NEXT WEEK...BEFORE CONSOLIDATING MORE ACROSS
THE DESERT SOUTHWEST BY THE MIDDLE OF NEXT WEEK.
FOR EASTERN KENTUCKY...THE FIRST MAIN SHORT WAVE WILL MOVE THROUGH
FRIDAY NIGHT INTO SATURDAY...BRINGING A CHANCE OF SHOWERS. GENERALLY
DRY WEATHER CAN BE EXPECTED FROM SATURDAY NIGHT THROUGH SUNDAY
NIGHT...AS HIGH PRESSURE TEMPORARILY BUILDS IN AT THE SURFACE. A
DEEPER TROUGH AXIS...WITH SOME SURFACE DEVELOPMENT NOTED BY THE
MODELS...WILL THEN AFFECT THE AREA FROM MONDAY THROUGH
TUESDAY. THIS SYSTEM WILL BRING SOME RENEWED CHANCES OF
SHOWERS...ALTHOUGH THERE WILL NOT BE AS MUCH LOW LEVEL MOISTURE TO
WORK WITH...SO STUCK FAIRLY CLOSE TO THE BLENDED GUIDANCE ON THE
POPS. DRY WEATHER WILL ENSUE ONCE AGAIN THEREAFTER...AS SURFACE HIGH
PRESSURE BUILDS IN ACROSS THE OHIO VALLEY.
TEMPERATURES WILL AVERAGE BELOW NORMAL THROUGH THE PERIOD...WITH
HIGHS MAINLY IN THE LOW TO MID 70S AND LOWS IN THE 50S.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z FRIDAY MORNING)
ISSUED AT 645 AM EDT THU SEP 11 2014
WIDESPREAD SHOWERS AND STORMS WILL LOCALLY HEAVY RAINFALL AND GUSTY
WINDS ARE STILL ON TAP TODAY AT ALL FOUR TAF SITES. MVFR AND AT TIMES
IFR CONDITIONS WILL BE POSSIBLE DUE TO HEAVY RAINFALL AND FOG WITH
SHOWERS AND STORMS TODAY. THE RAIN IS EXPECTED TO LAST ALL DAY BEFORE
TAPERING OFF THIS EVENING. WINDS ARE EXPECTED TO SHIFT TO TO THE WEST
LATE THIS AFTERNOON AND THEN TO THE NORTH THIS EVENING AS THE FRONT
MOVES PAST. LOW LEVEL CLOUD COVER WILL LIKELY PLAGUE THE TAF SITES
THROUGH TOMORROW MORNING AS THE FRONT STALLS OUT TO OUR SOUTH AND
MOIST AIR CONTINUES TO RIDE UP AND OVER THE BOUNDARY. ISOLATED RAIN
SHOWERS WILL ALSO LINGER OVERNIGHT INTO EARLY TOMORROW...PARTICULARLY
NEAR LOZ AND SME...WHICH WILL BE CLOSER TO THE FRONT.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...HAL
SHORT TERM...AR
LONG TERM...GEOGERIAN
AVIATION...AR
AREA FORECAST DISCUSSION
NWS JACKSON KY
645 AM EDT THU SEP 11 2014
.UPDATE...
ISSUED AT 645 AM EDT THU SEP 11 2014
MADE A FEW ADJUSTMENTS TO THE FORECAST GRIDS FOR EARLY THIS MORNING
BASED ON THE CURRENT RADAR TRENDS. DECIDED TO SLIGHTLY SPEED UP THE
EASTWARD PROGRESSION OF SHOWERS AND STORMS THIS MORNING PER LATEST
RADAR. BASED ON UPSTREAM SHOWER AND STORM FORMATION...AND THE STILL
SLOW EASTWARD MOVEMENT OF THE COLD FRONT...IT STILL APPEARS THAT
WIDESPREAD RAINFALL WILL OCCUR ACROSS EASTERN KENTUCKY THROUGH THIS
AFTERNOON. LOCALLY HEAVY RAINFALL...AND PERHAPS SOME ISOLATED
INSTANCES OF FLOODING...WILL STILL BE POSSIBLE AS NUMEROUS STORMS
WILL LIKELY MOVE ACROSS THE SAME LOCATIONS THROUGHOUT THE DAY.
&&
.SHORT TERM...(TODAY THROUGH FRIDAY)
ISSUED AT 323 AM EDT THU SEP 11 2014
THE MODELS WERE IN GOOD AGREEMENT WITH THE LARGE SCALE AND LOCAL
WEATHER PATTERN FOR THE FIRST 36 HOURS OF THE FORECAST. THE
NAM12...SREF...AND HRRR MODELS HAVE ALL HANDLED THE TIMING AND
EVOLUTION OF A LINE OF SHOWERS AND STORMS THAT IS CURRENTLY MOVING
ACROSS CENTRAL KENTUCKY AND SOUTHERN OHIO. THE NAM12 AND SREF SEEM TO
DO A BETTER JOB OF HANDLING THE EVOLUTION OF THIS LINE OF SHOWERS AND
STORMS AFTER SUNRISE TODAY THAN THE HRRR...SO THOSE TWO MODELS WERE
USED TO CREATE THE NEW FORECAST. THE MODELS SUGGEST A STRONG COLD
FRONT WILL MOVE ACROSS CENTRAL AND EASTERN KENTUCKY TODAY...WITH THE
BOUNDARY EXITING THE AREA LATE THIS AFTERNOON. WIDESPREAD SHOWERS AND
STORMS ARE EXPECTED TO CONTINUE FIRING ALONG AND JUST AHEAD OF THIS
FRONT...WITH THE PEAK IN ACTIVITY OCCURRING BETWEEN ROUGHLY NOON AND
5 PM. THE LATEST FORECAST SOUNDINGS CONTINUE TO SUPPORT THE POTENTIAL
FOR LOCALLY HEAVY RAINFALL...WITH PRECIPITABLE WATER VALUES OF AROUND
2 INCHES PERSISTING THROUGH THE OVERNIGHT HOURS. SOME OF THE STRONGER
THUNDERSTORMS COULD ALSO PRODUCE GUSTY WINDS...BUT LOCALLY HEAVY
RAINFALL WILL BE THE PRIMARY THREAT. THE RAIN CHANCES WILL NOT END
ONCE THE FRONT HAS PASSED BY US...HOWEVER. THE BOUNDARY IS EXPECTED
TO STALL ACROSS THE TENNESSEE VALLEY ON FRIDAY. WAVES OF LOW PRESSURE
ARE THEN PROGGED TO MIGRATE FROM WEST TO EAST ALONG THE FRONT. THESE
DISTURBANCES WILL BRING ENOUGH LIFT AND MOISTURE TO LOCATIONS SOUTH
OF THE MOUNTAIN PARKWAY TO PERHAPS FIRE OFF ISOLATED TO SCATTERED
RAIN SHOWERS LATE TONIGHT THROUGH THE END OF THE DAY ON FRIDAY.
ONCE THE FRONT MOVES THROUGH EARLY TONIGHT...AN UNSEASONABLY COOL
CANADIAN AIR MASS WILL SETTLE OVER THE AREA. THIS AIR MASS WILL BRING
FALL LIKE TEMPERATURES TO EASTERN KENTUCKY TONIGHT AND FRIDAY. THE
COOL WEATHER WILL FIRST BE EXPERIENCED LATE TONIGHT...AS WINDS SHIFT
TO THE NORTH AND THE COOL AIR FULLY INVADES THE REGION. TONIGHTS
LOWS ARE EXPECTED TO BOTTOM OUT IN THE LOW TO MID 60S FOR MOST
LOCATIONS. FOLKS ALONG AND NORTH OF THE I-64 CORRIDOR MAY SEE THE
MERCURY DIP INTO THE UPPER 50S BY FRIDAY MORNING. HIGH TEMPERATURES
ON FRIDAY WILL LIKELY ONLY CLIMB INTO THE LOW TO MID 70S ACROSS THE
AREA.
.LONG TERM...(FRIDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 431 AM EDT THU SEP 11 2014
THE MODELS ARE IN GOOD AGREEMENT WITH THE LONG WAVE PATTERN THROUGH
THE PERIOD. PROGRESSIVE AND AMPLIFIED FLOW WILL CONTROL ACROSS THE
NORTHERN HALF OF THE CONUS AS SEVERAL PASSING SHORT WAVES HELP TO
REINFORCE TROUGHING ACROSS THE REGION. UPPER LEVEL RIDGING HANGING ON
ACROSS THE SOUTHERN CONUS WILL GRADUALLY DAMPEN AND GET SUPPRESSED
FURTHER SOUTH INTO EARLY NEXT WEEK...BEFORE CONSOLIDATING MORE ACROSS
THE DESERT SOUTHWEST BY THE MIDDLE OF NEXT WEEK.
FOR EASTERN KENTUCKY...THE FIRST MAIN SHORT WAVE WILL MOVE THROUGH
FRIDAY NIGHT INTO SATURDAY...BRINGING A CHANCE OF SHOWERS. GENERALLY
DRY WEATHER CAN BE EXPECTED FROM SATURDAY NIGHT THROUGH SUNDAY
NIGHT...AS HIGH PRESSURE TEMPORARILY BUILDS IN AT THE SURFACE. A
DEEPER TROUGH AXIS...WITH SOME SURFACE DEVELOPMENT NOTED BY THE
MODELS...WILL THEN AFFECT THE AREA FROM MONDAY THROUGH
TUESDAY. THIS SYSTEM WILL BRING SOME RENEWED CHANCES OF
SHOWERS...ALTHOUGH THERE WILL NOT BE AS MUCH LOW LEVEL MOISTURE TO
WORK WITH...SO STUCK FAIRLY CLOSE TO THE BLENDED GUIDANCE ON THE
POPS. DRY WEATHER WILL ENSUE ONCE AGAIN THEREAFTER...AS SURFACE HIGH
PRESSURE BUILDS IN ACROSS THE OHIO VALLEY.
TEMPERATURES WILL AVERAGE BELOW NORMAL THROUGH THE PERIOD...WITH
HIGHS MAINLY IN THE LOW TO MID 70S AND LOWS IN THE 50S.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z FRIDAY MORNING)
ISSUED AT 645 AM EDT THU SEP 11 2014
WIDESPREAD SHOWERS AND STORMS WILL LOCALLY HEAVY RAINFALL AND GUSTY
WINDS ARE STILL ON TAP TODAY AT ALL FOUR TAF SITES. MVFR AND AT TIMES
IFR CONDITIONS WILL BE POSSIBLE DUE TO HEAVY RAINFALL AND FOG WITH
SHOWERS AND STORMS TODAY. THE RAIN IS EXPECTED TO LAST ALL DAY BEFORE
TAPERING OFF THIS EVENING. WINDS ARE EXPECTED TO SHIFT TO TO THE WEST
LATE THIS AFTERNOON AND THEN TO THE NORTH THIS EVENING AS THE FRONT
MOVES PAST. LOW LEVEL CLOUD COVER WILL LIKELY PLAGUE THE TAF SITES
THROUGH TOMORROW MORNING AS THE FRONT STALLS OUT TO OUR SOUTH AND
MOIST AIR CONTINUES TO RIDE UP AND OVER THE BOUNDARY. ISOLATED RAIN
SHOWERS WILL ALSO LINGER OVERNIGHT INTO EARLY TOMORROW...PARTICULARLY
NEAR LOZ AND SME...WHICH WILL BE CLOSER TO THE FRONT.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...AR
SHORT TERM...AR
LONG TERM...GEOGERIAN
AVIATION...AR
AREA FORECAST DISCUSSION
NWS JACKSON KY
431 AM EDT THU SEP 11 2014
.SHORT TERM...(TODAY THROUGH FRIDAY)
ISSUED AT 323 AM EDT THU SEP 11 2014
THE MODELS WERE IN GOOD AGREEMENT WITH THE LARGE SCALE AND LOCAL
WEATHER PATTERN FOR THE FIRST 36 HOURS OF THE FORECAST. THE
NAM12...SREF...AND HRRR MODELS HAVE ALL HANDLED THE TIMING AND
EVOLUTION OF A LINE OF SHOWERS AND STORMS THAT IS CURRENTLY MOVING
ACROSS CENTRAL KENTUCKY AND SOUTHERN OHIO. THE NAM12 AND SREF SEEM TO
DO A BETTER JOB OF HANDLING THE EVOLUTION OF THIS LINE OF SHOWERS AND
STORMS AFTER SUNRISE TODAY THAN THE HRRR...SO THOSE TWO MODELS WERE
USED TO CREATE THE NEW FORECAST. THE MODELS SUGGEST A STRONG COLD
FRONT WILL MOVE ACROSS CENTRAL AND EASTERN KENTUCKY TODAY...WITH THE
BOUNDARY EXITING THE AREA LATE THIS AFTERNOON. WIDESPREAD SHOWERS AND
STORMS ARE EXPECTED TO CONTINUE FIRING ALONG AND JUST AHEAD OF THIS
FRONT...WITH THE PEAK IN ACTIVITY OCCURRING BETWEEN ROUGHLY NOON AND
5 PM. THE LATEST FORECAST SOUNDINGS CONTINUE TO SUPPORT THE POTENTIAL
FOR LOCALLY HEAVY RAINFALL...WITH PRECIPITABLE WATER VALUES OF AROUND
2 INCHES PERSISTING THROUGH THE OVERNIGHT HOURS. SOME OF THE STRONGER
THUNDERSTORMS COULD ALSO PRODUCE GUSTY WINDS...BUT LOCALLY HEAVY
RAINFALL WILL BE THE PRIMARY THREAT. THE RAIN CHANCES WILL NOT END
ONCE THE FRONT HAS PASSED BY US...HOWEVER. THE BOUNDARY IS EXPECTED
TO STALL ACROSS THE TENNESSEE VALLEY ON FRIDAY. WAVES OF LOW PRESSURE
ARE THEN PROGGED TO MIGRATE FROM WEST TO EAST ALONG THE FRONT. THESE
DISTURBANCES WILL BRING ENOUGH LIFT AND MOISTURE TO LOCATIONS SOUTH
OF THE MOUNTAIN PARKWAY TO PERHAPS FIRE OFF ISOLATED TO SCATTERED
RAIN SHOWERS LATE TONIGHT THROUGH THE END OF THE DAY ON FRIDAY.
ONCE THE FRONT MOVES THROUGH EARLY TONIGHT...AN UNSEASONABLY COOL
CANADIAN AIR MASS WILL SETTLE OVER THE AREA. THIS AIR MASS WILL BRING
FALL LIKE TEMPERATURES TO EASTERN KENTUCKY TONIGHT AND FRIDAY. THE
COOL WEATHER WILL FIRST BE EXPERIENCED LATE TONIGHT...AS WINDS SHIFT
TO THE NORTH AND THE COOL AIR FULLY INVADES THE REGION. TONIGHTS
LOWS ARE EXPECTED TO BOTTOM OUT IN THE LOW TO MID 60S FOR MOST
LOCATIONS. FOLKS ALONG AND NORTH OF THE I-64 CORRIDOR MAY SEE THE
MERCURY DIP INTO THE UPPER 50S BY FRIDAY MORNING. HIGH TEMPERATURES
ON FRIDAY WILL LIKELY ONLY CLIMB INTO THE LOW TO MID 70S ACROSS THE
AREA.
.LONG TERM...(FRIDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 431 AM EDT THU SEP 11 2014
THE MODELS ARE IN GOOD AGREEMENT WITH THE LONG WAVE PATTERN THROUGH
THE PERIOD. PROGRESSIVE AND AMPLIFIED FLOW WILL CONTROL ACROSS THE
NORTHERN HALF OF THE CONUS AS SEVERAL PASSING SHORT WAVES HELP TO
REINFORCE TROUGHING ACROSS THE REGION. UPPER LEVEL RIDGING HANGING ON
ACROSS THE SOUTHERN CONUS WILL GRADUALLY DAMPEN AND GET SUPPRESSED
FURTHER SOUTH INTO EARLY NEXT WEEK...BEFORE CONSOLIDATING MORE ACROSS
THE DESERT SOUTHWEST BY THE MIDDLE OF NEXT WEEK.
FOR EASTERN KENTUCKY...THE FIRST MAIN SHORT WAVE WILL MOVE THROUGH
FRIDAY NIGHT INTO SATURDAY...BRINGING A CHANCE OF SHOWERS. GENERALLY
DRY WEATHER CAN BE EXPECTED FROM SATURDAY NIGHT THROUGH SUNDAY
NIGHT...AS HIGH PRESSURE TEMPORARILY BUILDS IN AT THE SURFACE. A
DEEPER TROUGH AXIS...WITH SOME SURFACE DEVELOPMENT NOTED BY THE
MODELS...WILL THEN AFFECT THE AREA FROM MONDAY THROUGH
TUESDAY. THIS SYSTEM WILL BRING SOME RENEWED CHANCES OF
SHOWERS...ALTHOUGH THERE WILL NOT BE AS MUCH LOW LEVEL MOISTURE TO
WORK WITH...SO STUCK FAIRLY CLOSE TO THE BLENDED GUIDANCE ON THE
POPS. DRY WEATHER WILL ENSUE ONCE AGAIN THEREAFTER...AS SURFACE HIGH
PRESSURE BUILDS IN ACROSS THE OHIO VALLEY.
TEMPERATURES WILL AVERAGE BELOW NORMAL THROUGH THE PERIOD...WITH
HIGHS MAINLY IN THE LOW TO MID 70S AND LOWS IN THE 50S.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z THURSDAY NIGHT)
ISSUED AT 140 AM EDT THU SEP 11 2014
VFR CONDITIONS ARE EXPECTED TO PREVAIL THROUGH AROUND 11Z THIS
MORNING AT THE PRIMARY TAF SITES. IT LOOKS LIKE THE FIRST SHOWERS AND
STORMS WILL BEGIN MOVING ACROSS THE TAF SITES BEGINNING AT 10Z FOR
SME...11Z FOR LOZ...12Z FOR JKL...AND 13Z FOR SJS. MVFR TO IFR
CONDITIONS WILL BE POSSIBLE WITH ANY THUNDERSTORMS OR INTENSE
SHOWERS. LOCALLY HEAVY RAINFALL AND LIGHTNING WILL THE PRIMARY
CONCERNS FOR AVIATORS WITH ANY SHOWERS OR STORMS. THE COLD FRONT THAT
IS PRODUCING THE PRECIPITATION SHOULD BE THROUGH THE AREA BY AROUND
0Z THIS EVENING...WITH WINDS SHIFTING FROM SOUTHWEST TO WEST BEHIND
THE FRONT.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...AR
LONG TERM...GEOGERIAN
AVIATION...AR
AREA FORECAST DISCUSSION...UPDATED
NWS JACKSON KY
323 AM EDT THU SEP 11 2014
.SHORT TERM...(TODAY THROUGH FRIDAY)
ISSUED AT 3 23AM EDT THU SEP 11 2014
THE MODELS WERE IN GOOD AGREEMENT WITH THE LARGE SCALE AND LOCAL
WEATHER PATTERN FOR THE FIRST 36 HOURS OF THE FORECAST. THE
NAM12...SREF...AND HRRR MODELS HAVE ALL HANDLED THE TIMING AND
EVOLUTION OF A LINE OF SHOWERS AND STORMS THAT IS CURRENTLY MOVING
ACROSS CENTRAL KENTUCKY AND SOUTHERN OHIO. THE NAM12 AND SREF SEEM TO
DO A BETTER JOB OF HANDLING THE EVOLUTION OF THIS LINE OF SHOWERS AND
STORMS AFTER SUNRISE TODAY THAN THE HRRR...SO THOSE TWO MODELS WERE
USED TO CREATE THE NEW FORECAST. THE MODELS SUGGEST A STRONG COLD
FRONT WILL MOVE ACROSS CENTRAL AND EASTERN KENTUCKY TODAY...WITH THE
BOUNDARY EXITING THE AREA LATE THIS AFTERNOON. WIDESPREAD SHOWERS AND
STORMS ARE EXPECTED TO CONTINUE FIRING ALONG AND JUST AHEAD OF THIS
FRONT...WITH THE PEAK IN ACTIVITY OCCURRING BETWEEN ROUGHLY NOON AND
5 PM. THE LATEST FORECAST SOUNDINGS CONTINUE TO SUPPORT THE POTENTIAL
FOR LOCALLY HEAVY RAINFALL...WITH PRECIPITABLE WATER VALUES OF AROUND
2 INCHES PERSISTING THROUGH THE OVERNIGHT HOURS. SOME OF THE STRONGER
THUNDERSTORMS COULD ALSO PRODUCE GUSTY WINDS...BUT LOCALLY HEAVY
RAINFALL WILL BE THE PRIMARY THREAT. THE RAIN CHANCES WILL NOT END
ONCE THE FRONT HAS PASSED BY US...HOWEVER. THE BOUNDARY IS EXPECTED
TO STALL ACROSS THE TENNESSEE VALLEY ON FRIDAY. WAVES OF LOW PRESSURE
ARE THEN PROGGED TO MIGRATE FROM WEST TO EAST ALONG THE FRONT. THESE
DISTURBANCES WILL BRING ENOUGH LIFT AND MOISTURE TO LOCATIONS SOUTH
OF THE MOUNTAIN PARKWAY TO PERHAPS FIRE OFF ISOLATED TO SCATTERED
RAIN SHOWERS LATE TONIGHT THROUGH THE END OF THE DAY ON FRIDAY.
ONCE THE FRONT MOVES THROUGH EARLY TONIGHT...AN UNSEASONABLY COOL
CANADIAN AIR MASS WILL SETTLE OVER THE AREA. THIS AIR MASS WILL BRING
FALL LIKE TEMPERATURES TO EASTERN KENTUCKY TONIGHT AND FRIDAY. THE
COOL WEATHER WILL FIRST BE EXPERIENCED LATE TONIGHT...AS WINDS SHIFT
TO THE NORTH AND THE COOL AIR FULLY INVADES THE REGION. TONIGHTS
LOWS ARE EXPECTED TO BOTTOM OUT IN THE LOW TO MID 60S FOR MOST
LOCATIONS. FOLKS ALONG AND NORTH OF THE I-64 CORRIDOR MAY SEE THE
MERCURY DIP INTO THE UPPER 50S BY FRIDAY MORNING. HIGH TEMPERATURES
ON FRIDAY WILL LIKELY ONLY CLIMB INTO THE LOW TO MID 70S ACROSS THE
AREA.
.LONG TERM...(FRIDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 323 AM EDT THU SEP 11 2014
AN EXTENDED DISCUSSION WILL BE ISSUED SHORTLY.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z THURSDAY NIGHT)
ISSUED AT 140 AM EDT THU SEP 11 2014
VFR CONDITIONS ARE EXPECTED TO PREVAIL THROUGH AROUND 11Z THIS
MORNING AT THE PRIMARY TAF SITES. IT LOOKS LIKE THE FIRST SHOWERS AND
STORMS WILL BEGIN MOVING ACROSS THE TAF SITES BEGINNING AT 10Z FOR
SME...11Z FOR LOZ...12Z FOR JKL...AND 13Z FOR SJS. MVFR TO IFR
CONDITIONS WILL BE POSSIBLE WITH ANY THUNDERSTORMS OR INTENSE
SHOWERS. LOCALLY HEAVY RAINFALL AND LIGHTNING WILL THE PRIMARY
CONCERNS FOR AVIATORS WITH ANY SHOWERS OR STORMS. THE COLD FRONT THAT
IS PRODUCING THE PRECIPITATION SHOULD BE THROUGH THE AREA BY AROUND
0Z THIS EVENING...WITH WINDS SHIFTING FROM SOUTHWEST TO WEST BEHIND
THE FRONT.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...AR
LONG TERM...GEOGERIAN
AVIATION...AR
AREA FORECAST DISCUSSION
NWS JACKSON KY
306 AM EDT THU SEP 11 2014
.SHORT TERM...(TODAY THROUGH FRIDAY)
ISSUED AT 305 AM EDT THU SEP 11 2014
THE MODELS WERE IN GOOD AGREEMENT WITH THE LARGE SCALE AND LOCAL
WEATHER PATTERN FOR THE FIRST 36 HOURS OF THE FORECAST. THE
NAM12...SREF...AND HRRR MODELS HAVE ALL HANDLED THE TIMING AND
EVOLUTION OF A LINE OF SHOWERS AND STORMS THAT IS CURRENTLY MOVING
ACROSS CENTRAL KENTUCKY AND SOUTHERN OHIO. THE NAM12 AND SREF SEEM TO
DO A BETTER JOB OF HANDLING THE EVOLUTION OF THIS LINE OF SHOWERS AND
STORMS AFTER SUNRISE TODAY THAN THE HRRR...SO THOSE TWO MODELS WERE
USED TO CREATE THE NEW FORECAST. THE MODELS SUGGEST A STRONG COLD
FRONT WILL MOVE ACROSS CENTRAL AND EASTERN KENTUCKY TODAY...WITH THE
BOUNDARY EXITING THE AREA LATE THIS AFTERNOON. WIDESPREAD SHOWERS AND
STORMS ARE EXPECTED TO CONTINUE FIRING ALONG AND JUST AHEAD OF THIS
FRONT...WITH THE PEAK IN ACTIVITY OCCURRING BETWEEN ROUGHLY NOON AND
5 PM. THE LATEST FORECAST SOUNDINGS CONTINUE TO SUPPORT THE POTENTIAL
FOR LOCALLY HEAVY RAINFALL...WITH PRECIPITABLE WATER VALUES OF AROUND
2 INCHES PERSISTING THROUGH THE OVERNIGHT HOURS. SOME OF THE STRONGER
THUNDERSTORMS COULD ALSO PRODUCE GUSTY WINDS...BUT LOCALLY HEAVY
RAINFALL WILL BE THE PRIMARY THREAT. ONCE THE FRONT MOVES THROUGH
EARLY TONIGHT...AN UNSEASONABLY COOL CANADIAN AIR MASS WILL SETTLE
OVER THE AREA. THIS AIR MASS WILL BRING FALL LIKE TEMPERATURES TO
EASTERN KENTUCKY TONIGHT AND FRIDAY. THE COOL WEATHER WILL FIRST BE
EXPERIENCED LATE TONIGHT...AS WINDS SHIFT TO THE NORTH AND THE COOL
AIR FULL INVADES THE REGIONS. TONIGHTS LOWS ARE EXPECTED TO BOTTOM
OUT IN THE LOW TO MID 60S FOR MOST LOCATIONS. FOLKS ALONG AND NORTH
OF THE I-64 CORRIDOR MAY SEE THE MERCURY DIP INTO THE UPPER 50S BY
FRIDAY MORNING. HIGH TEMPERATURES ON FRIDAY WILL LIKELY ONLY CLIMB
INTO THE LOW TO MID 70S ACROSS THE AREA.
.LONG TERM...(FRIDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 305 AM EDT THU SEP 11 2014
AN EXTENDED DISCUSSION WILL BE ISSUED SHORTLY.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z THURSDAY NIGHT)
ISSUED AT 140 AM EDT THU SEP 11 2014
VFR CONDITIONS ARE EXPECTED TO PREVAIL THROUGH AROUND 11Z THIS
MORNING AT THE PRIMARY TAF SITES. IT LOOKS LIKE THE FIRST SHOWERS AND
STORMS WILL BEGIN MOVING ACROSS THE TAF SITES BEGINNING AT 10Z FOR
SME...11Z FOR LOZ...12Z FOR JKL...AND 13Z FOR SJS. MVFR TO IFR
CONDITIONS WILL BE POSSIBLE WITH ANY THUNDERSTORMS OR INTENSE
SHOWERS. LOCALLY HEAVY RAINFALL AND LIGHTNING WILL THE PRIMARY
CONCERNS FOR AVIATORS WITH ANY SHOWERS OR STORMS. THE COLD FRONT THAT
IS PRODUCING THE PRECIPITATION SHOULD BE THROUGH THE AREA BY AROUND
0Z THIS EVENING...WITH WINDS SHIFTING FROM SOUTHWEST TO WEST BEHIND
THE FRONT.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...AR
LONG TERM...GEOGERIAN
AVIATION...AR
AREA FORECAST DISCUSSION
NWS JACKSON KY
140 AM EDT THU SEP 11 2014
.UPDATE...
ISSUED AT 140 AM EDT THU SEP 11 2014
INGESTED THE LATEST OBSERVATIONAL DATA INTO THE FORECAST GRIDS TO
ESTABLISH NEW TRENDS AND FRESHEN UP THE EXISTING FORECAST FOR THE
REST OF THE NIGHT. THE CHANGES MADE TO THE GRIDS WERE MINOR ENOUGH TO
NOT WARRANT A FORECAST UPDATE AT THIS TIME.
UPDATE ISSUED AT 1049 PM EDT WED SEP 10 2014
HAVE SLOWED DOWN THE PRECIPITATION ONSET JUST A BIT MORE BASED ON THE
LATEST RADAR AND HRRR MODEL TRENDS. THE LATEST IR SATELLITE SHOWS
QUITE A BIT OF CLEARING ACROSS OUR AREA CURRENTLY...AND A FEW OF THE
NORMALLY COOLER VALLEYS HAVE ALREADY DIPPED INTO THE UPPER 60S.
CLOUDS SHOULD FILL IN NICELY BETWEEN 06 AND 12Z...HOWEVER DID LOWER
SOME OF THE LOW TEMPERATURES IN THE EAST WHERE SOME DECENT CLEARING
WILL HANG ON FOR THE NEXT 2 TO 3 HOURS...ALLOWING FOR ANOTHER DEGREE
DROP OFF OR SO. UPDATES HAVE BEEN SENT.
UPDATE ISSUED AT 820 PM EDT WED SEP 10 2014
BASED ON OBS AND AFTERNOON MODEL RUNS...HAVE SLOWED THE ARRIVAL OF
PRECIP TONIGHT...BUT THE OVERNIGHT REMAINS UNCHANGED...WITH THE SAME
12 HOUR POPS FOR THE PERIOD.
&&
.SHORT TERM...(THIS EVENING THROUGH THURSDAY NIGHT)
ISSUED AT 400 PM EDT WED SEP 10 2014
MODELS ARE IN GOOD AGREEMENT FOR THE WEATHER EVENT TO AFFECT US
DURING THE PERIOD. A COLD FRONT WILL MOVE SOUTHEAST...PASSING THROUGH
KY ON THURSDAY AND THURSDAY EVENING. SHOWERS WILL OCCUR NEAR AND
AHEAD OF THE FRONT...ENTERING THE JKL FORECAST AREA OVERNIGHT...WITH
MOST OF THE PRECIP EXITING INTO TN AND VA BY THURSDAY EVENING.
LIMITED HEATING IS EXPECTED ON THURSDAY AND LAPSE RATES WILL BE NEAR
MOIST ADIABATIC...AND WINDS ALOFT ONLY MODEST. SO...DESPITE AMPLE
MOISTURE...CONVECTION SHOULD NOT BE TOO RAMBUNCTIOUS. PRECIPITABLE
WATER WILL BE NEAR 2 INCHES...AND LOCALLY HEAVY RAINFALL MAY OCCUR
WHERE CELLS TRAIN...BUT THE CELLS WILL AT LEAST BE MOVING ALONG.
.LONG TERM...(FRIDAY THROUGH WEDNESDAY)
ISSUED AT 400 PM EDT WED SEP 10 2014
ATTENTION TURNS TO A SIGNIFICANT SHORT WAVE THAT WILL MOVE FROM THE
NORTH PLAINS EAST TO THE GREAT LAKES FRIDAY INTO SATURDAY. THIS WAVE
MOVES PAST EAST KENTUCKY DURING THE DAY SATURDAY FOLLOWED BY
FLATTER...BUT STILL RATHER FAST...FLOW INTO THE DAY SUNDAY. FOR THIS
TIME FRAME...THROUGH THE DAY TUESDAY...WILL FAVOR A GENERAL MODEL
BLEND. THE MODELS KEEP THIS SORT OF ABNORMALLY COOL PATTERN GOING
THROUGH THEIR RUN SUGGESTING THAT OUR DAYS OF SUMMER-LIKE WEATHER MAY
BE OVER FOR THE SEASON...THOUGH BEING KENTUCKY IT WOULD NOT TAKE
MUCH OF A WIGGLE TO BRING SOME SOUTHERN WARMTH BACK NORTH. WE SHALL
SEE...
THE RUB WITH THE FORECAST THROUGH THE FIRST PART OF THE WEEKEND WILL
BE THE POSSIBILITY THAT THE FRONT DOES NOT COMPLETELY CLEAR THE CWA
AND LINGERS CLOSE ENOUGH FOR SHOWERS TO ACCOMPANY THE FALL-LIKE COOL
DOWN FOR OUR SOUTHERN MOST LOCATIONS. THE SHOWER THREAT INCREASES
DURING FRIDAY NIGHT THROUGH THE DAY SATURDAY AS A REINFORCING COLD
FRONT MOVES THROUGH THE OHIO VALLEY. THIS FRONT SHOULD HAVE A BETTER
PUSH BEHIND IT AND HELP TO CLEAR OUT LINGERING SHOWER THREATS FOR AT
LEAST A DAY OR SO ACROSS ALL OF THE AREA. THE HIGH PRESSURE
ASSOCIATED WITH THIS COOL BLAST WILL MODERATE SOMEWHAT AND MOVE BY TO
THE NORTHEAST BY MONDAY MORNING.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z THURSDAY NIGHT)
ISSUED AT 140 AM EDT THU SEP 11 2014
VFR CONDITIONS ARE EXPECTED TO PREVAIL THROUGH AROUND 11Z THIS
MORNING AT THE PRIMARY TAF SITES. IT LOOKS LIKE THE FIRST SHOWERS AND
STORMS WILL BEGIN MOVING ACROSS THE TAF SITES BEGINNING AT 10Z FOR
SME...11Z FOR LOZ...12Z FOR JKL...AND 13Z FOR SJS. MVFR TO IFR
CONDITIONS WILL BE POSSIBLE WITH ANY THUNDERSTORMS OR INTENSE
SHOWERS. LOCALLY HEAVY RAINFALL AND LIGHTNING WILL THE PRIMARY
CONCERNS FOR AVIATORS WITH ANY SHOWERS OR STORMS. THE COLD FRONT THAT
IS PRODUCING THE PRECIPITATION SHOULD BE THROUGH THE AREA BY AROUND
0Z THIS EVENING...WITH WINDS SHIFTING FROM SOUTHWEST TO WEST BEHIND
THE FRONT.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...AR
SHORT TERM...HAL
LONG TERM...JKL
AVIATION...AR
AREA FORECAST DISCUSSION...UPDATED
NWS PADUCAH KY
1141 PM CDT Wed Sep 10 2014
.UPDATE...
Issued at 1141 PM CDT WED SEP 10 2014
Updated the aviation discussion for the 06Z TAF issuance.
&&
.SHORT TERM...(Tonight through Friday night)
Issued at 323 PM CDT WED SEP 10 2014
The showers are still trying to dissipate over southern Illinois,
and now a tiny heavy shower has develop near KSAR in the last
scan or two. The latest HRRR indicates that there may be some
heavier convective elements with this pesky band of showers, as it
moves eastward toward the EVV Tri State late this afternoon.
Widespread cloud cover has stunted surface-based instability
today, and this may help keep the severe weather threat in check
as we move into this evening. Model soundings from southern
Illinois and southwest Indiana reveal very weak lapse rates, and
overall instability. There is decent low-level shear, possibly
enough to support a few rotating updrafts. The low-level shear
will weaken through the evening, and there is little shear above 3
km. Cannot rule out a stray severe thunderstorm, especially if it
can display supercellular characteristics. Damaging winds still
appear to be the primary concern, but large hail and a brief
tornado cannot be ruled out.
Precipitable water values are well above 2 inches, and this could
lead to some torrential rainfall. Generally followed HPC QPF
through Thursday, and this yields 1.5-2" over much of the area,
with the possible exception of the far southeast corner of the
forecast area. 1-hour and 3-hour Flash flood Guidance is well over
2", so will not be issuing a Flash Flood Watch at this time. Some
nuisance flooding in low-lying and poorly draining areas is
possible, but major problems are not expected. The heaviest rains
will be waning over the southern half of the area toward sunrise.
Still not sure when/where convective initiation will occur, but
the latest HRRR runs have been consistent and developing scattered
convection across northern portions of southeast Missouri into
southern Illinois by 00Z. Convection currently developing along
the cold front from west central Illinois into central Missouri is
moving east and should not pose any immediate concern for our
region, but figure that the convection will fill in between it and our
scattered convection through the evening.
Will keep some decent PoPs in the southeast Thursday morning, but
it should be drying out over most areas in the afternoon. Thursday
night and Friday morning should be dry, but as the next rather
sharp upper-level storm system rotates eastward out of the
central/northern Plains, would not be surprised to see some
showers develop, as moisture is drawn back northward over the
shallow Canadian airmass. This would primarily be in the south
Friday afternoon, and then throughout the area Friday night. Still
don`t think there will be much precipitation, but a slight chance
of showers seems reasonable for both periods.
As for temperatures, stayed close to the consensus of all guidance
for lows tonight with the frontal passage. With clouds,
precipitation and cool advection, went under guidance in the
southeast Thursday. Went near consensus for lows Thursday night,
and then went below guidance Friday and near or just above it Friday
night.
.LONG TERM...(Saturday through Wednesday)
Issued at 323 PM CDT WED SEP 10 2014
Surface high pressure will build into the area on Saturday,
providing much drier air and lowering temperatures. The center of
the high will pass over the Great Lakes region and then move into
the New England states. Our region should remain dry through the
weekend though as weak high pressure continues to stay situated over
us.
Models try and bring a front into the area on Monday. The front
weakens substantially as it arrives Monday into Monday night, so
chances for precipitation appear minimal at this time but cloud
cover should increase. Most of the upper level dynamics and moisture
look to be to the north of our area. However, we will have to watch
Monday night, as a few of the GFS ensemble members and the 12Z Euro
are hinting that this front could produce some light precipitation,
especially in our northwestern counties. Even the operational GFS
indicates lower level moisture increasing by Monday night.
For Tuesday, models differ on the degree of dry air filtering into
the area, in association with the area of high pressure that moves
toward us. The 12Z GFS is much more robust in scouring out the
moisture while the 00Z ECMWF seems to keep plenty of moisture
lingering until Wednesday. The 12Z run of the ECMWF is a bit more
pronounced with drying us out now but still not as much as the GFS.
Nevertheless, it looks like we`ll be dry on Tuesday. On Wednesday,
the GFS starts to bring better moisture back into the area from the
west and even hints at possible precipitation chances out in SEMO as
well. However, the 12Z run was the only run that was this quick in
bringing precipitation back in and even the 12Z ECMWF was dry.
Temperatures will be coolest on Saturday and remain in the 70s for
the majority of the extended period. There might be a few places
that reach in the lower 80s by next week. Lows will generally be in
the 50s but some upper 40s might be attainable on Saturday night
especially in the north.
&&
.AVIATION...
Issued at 1141 PM CDT WED SEP 10 2014
With the passage of a strong cold front, showers and thunderstorms
producing IFR/MVFR conditions will continue across all TAF sites
through the first third of the period. Afer the precipitation
ends. MVFR cigs will continue through 18-20Z, then VFR. Winds will
become northwest AOB 10 knots in the wake of the front through the
first half of the period, then veer around to the north.
&&
.PAH WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
MO...NONE.
IN...NONE.
KY...NONE.
&&
$$
AVIATION/PUBLIC...JP
AREA FORECAST DISCUSSION
NWS SHREVEPORT LA
1015 PM CDT FRI SEP 12 2014
.DISCUSSION...
COLD FRONT SOUTH OF INTERSTATE 20 AND NEARING THE SOUTHERN PARTS
OF EAST AND NORTHEAST TEXAS ACROSS LOWER PARTS OF NORTHWEST AND
NORTH CENTRAL LOUISIANA LATE THIS EVENING. RAIN AND EMBEDDED
HEAVIER SHOWERS CONTINUED ALONG AND IN WAKE OF THE COLD FRONT
AS MOISTURE LIFTS NEAR THE BOUNDARY AND COOLS IN THE COOLER AIR TO
THE RADAR OF THE BOUNDARY. HAVE REMOVED THUNDERSTORMS FROM THE
WORDING OF THE ZONES FOR THE REST OF TONIGHT AND INTO TOMORROW.
SOME ISOLATED THUNDERSTORMS MAY OCCUR BUT MOST LOCATIONS WILL NOT
HAVE THUNDERSTORMS. RAIN WILL TAPER OFF FROM NORTHWEST TO SOUTHEAST.
ADJUSTED THE TEMPERATURES LOWER FOR PARTS OF EAST AND NORTHEAST
TEXAS AND SOUTHEAST OKLAHOMA...WHERE COLD AIR WILL MORE PRONE TO
ENTER THE REGION. /06/
&&
.PREV DISCUSSION... /ISSUED 659 PM CDT FRI SEP 12 2014/
AVIATION...
FOR THE 13/00Z TAFS...A BAND OF SHWRS/TSTMS CONTINUES TO SLOWLY
MOVE NWD ACROSS E TX/CNTRL LA BUT THE OVERALL INTENSITY OF THE
CONVECTION IS GRADUALLY DIMINISHING. SCT SHWRS WILL LIKELY PERSIST
THROUGH SATURDAY AFTERNOON...MAINLY S OF I-20...BUT WHETHER OR NOT
THE PRECIP ACTUALLY AFFECTS ANY OF THE TAF SITES IS MORE
UNCERTAIN. BEST RAIN CHANCES FOR THIS PERIOD SHOULD BE AT KLFK AS
COOLER AND DRIER AIR SLOWLY WORKS INTO THE AREA FROM THE NORTH.
CIGS EXPECTED TO FALL INTO THE MVFR/IFR RANGE DURING THE OVERNIGHT
HRS WITH VERY LITTLE IMPROVEMENT DURING THE DAY SATURDAY. TIGHT
PRESSURE GRADIENT BEHIND THE COLD FRONT WILL KEEP NLY WINDS AROUND
10 KTS WITH A FEW HIGHER GUSTS BUT SPEEDS SHOULD DIMINISH SOMEWHAT
SATURDAY AS A SFC HIGH BUILDS SWD AND THE PRESSURE GRADIENT
RELAXES. /09/
PREV DISCUSSION... /ISSUED 348 PM CDT FRI SEP 12 2014/
DISCUSSION...
OUR WEAK COLD FRONT REMAINS STATIONARY JUST S OF THE I-20 CORRIDOR
OF E TX/N LA THIS AFTERNOON...WITH A LARGE SUCKER HOLE RECENTLY
OPENING UP ACROSS NW LA. TEMPS IN THESE AREAS HAVE WARMED INTO THE
LOWER/MID 80S THIS AFTERNOON...BUT TEMPS REMAIN MUCH COOLER UNDER
THE LOW STRATUS FARTHER W AND N. AS EXPECTED...SCT CONVECTION HAS
DEVELOPED ALONG THE FRONTAL ZONE OVER DEEP E TX...WITH THE WEAK
SEABREEZE APPROACHING THIS AREA AS WELL AS WCNTRL LA FROM SE TX/SW
LA. BELIEVE THAT THIS CONVECTION WILL CONTINUE THROUGH A PORTION
OF THIS EVENING BEFORE DIMINISHING WITH THE LOSS OF
HEATING/INSTABILITY...WITH THE FRONTAL BNDRY EXPECTED TO SLOWLY
DRIFT BACK S ACROSS THIS AREA AND THE SRN SECTIONS OF NCNTRL LA
THIS EVENING/OVERNIGHT. THE HRRR AND TO SOME EXTENT...THE 12Z WRF
DOES INDICATE THE ONGOING CONVECTION POSSIBLY BUILDING BACK A
LITTLE FARTHER NNE TO NEAR/JUST S OF THE I-20 CORRIDOR OF E TX/NW
LA THIS EVENING...WITH ONLY ISOLATED -SHRA EXPECTED FARTHER N
CLOSER TO THE WEAK 850MB TROUGH AS IT REMAINS JUST N OF THE REGION
OVER SE OK/WRN AND CNTRL AR. DID MAINTAIN HIGH CHANCE POPS FOR
AREAS NEAR/S OF THE FRONT THIS EVENING...LOWERING POPS A TAD LATE
AS THE CONVECTION SHOULD WANE ONCE OVERALL FORCING WEAKENS. SHOULD
SEE A WIDE RANGE IN MIN TEMPS OVERNIGHT GIVEN THE SHALLOW NATURE
OF THE POST-FRONTAL AIR MASS...WITH TEMPS POSSIBLY FALLING INTO
THE UPPER 50S OVER SE OK/SW AR.
THE WEAK COLD FRONT IS EXPECTED TO NEAR THE COAST AROUND 12Z
SATURDAY...WITH THE POST-FRONTAL STRATUS HOLDING TOUGH THROUGH THE
DAY. GIVEN THE DEPTH OF THE MOISTURE IN PLACE...DID INSERT SLIGHT
CHANCE POPS AREAWIDE SATURDAY AS ANY WEAK FORCING WILL EASILY
RESULT IN -SHRA DEVELOPMENT...WITH DAYTIME TEMPS ONLY RISING 10
DEGREES OR SO FROM THE MORNING LOWS. THE LOW STRATUS SHOULD BEGIN
TO SLOWLY LIFT SUNDAY...POSSIBLY SCATTERING OUT IN THE AFTERNOON
OVER PORTIONS OF THE REGION. THIS SHOULD RESULT IN MODERATING
TEMPS...ALTHOUGH SFC RIDGING IN PLACE WILL MAINTAIN ABNORMALLY LOW
DEWPOINTS AND COMFORTABLE RH/S FOR THIS TIME OF YEAR. SHOULD BEGIN
TO SEE A RETURN OF HIGHER RH/S BY TUESDAY AS THE BROAD UPPER LEVEL
LOW/TROPICAL WAVE...NOW OVER SRN FL...BEGINS TO SHIFT W ACROSS THE
GULF OF MX THIS WEEKEND AND POSSIBLY IMPACT THE TX COAST.
ATTM...ENOUGH SHEAR ALOFT SHOULD KEEP THIS SYSTEM FROM
INTENSIFYING THIS WEEKEND AND EARLY NEXT WEEK...ALTHOUGH IT WILL
HELP ENHANCE THE SEABREEZE AS IT MOVES INLAND ACROSS SE AND DEEP E
TX/SRN AND CNTRL LA TUESDAY. IN ADDITION...A SHORTWAVE IN THE NW
FLOW ALOFT WILL DROP SE ACROSS THE REGION TUESDAY AS WELL...WHICH
COULD FURTHER ENHANCE FORCING OVER THE SRN SECTIONS OF THE REGION.
HAVE INCREASED POPS TO MID CHANCE S OF I-20 TUESDAY...WITH
CONVECTION DIMINISHING TUESDAY NIGHT/WEDNESDAY AS DRIER AIR ALOFT
MIXES SE IN WAKE OF THIS SHORTWAVE. A DRY NW FLOW LOOKS TO PERSIST
THROUGHOUT THE REMAINDER OF THE WEEK AS UPPER LEVEL RIDGING BUILDS
OVER THE DESERT SW AND THE ROCKIES. TEMPS SHOULD BE NEAR CLIMO
THROUGH THE PERIOD AS WELL.
PRELIMS TO FOLLOW BELOW...
15
&&
.PRELIMINARY POINT TEMPS/POPS...
SHV 64 76 61 85 66 / 30 20 10 10 10
MLU 64 79 61 84 65 / 50 20 10 10 10
DEQ 58 71 57 79 62 / 20 10 10 10 10
TXK 60 73 58 81 63 / 20 20 10 10 10
ELD 61 74 57 81 62 / 30 20 10 10 10
TYR 62 75 61 85 68 / 30 20 10 10 10
GGG 64 76 61 85 66 / 40 20 10 10 10
LFK 67 80 64 88 68 / 60 30 10 10 10
&&
.SHV WATCHES/WARNINGS/ADVISORIES...
AR...NONE.
LA...NONE.
OK...NONE.
TX...NONE.
&&
$$
06
AREA FORECAST DISCUSSION
NWS SHREVEPORT LA
659 PM CDT FRI SEP 12 2014
.AVIATION...
FOR THE 13/00Z TAFS...A BAND OF SHWRS/TSTMS CONTINUES TO SLOWLY
MOVE NWD ACROSS E TX/CNTRL LA BUT THE OVERALL INTENSITY OF THE
CONVECTION IS GRADUALLY DIMINISHING. SCT SHWRS WILL LIKELY PERSIST
THROUGH SATURDAY AFTERNOON...MAINLY S OF I-20...BUT WHETHER OR NOT
THE PRECIP ACTUALLY AFFECTS ANY OF THE TAF SITES IS MORE
UNCERTAIN. BEST RAIN CHANCES FOR THIS PERIOD SHOULD BE AT KLFK AS
COOLER AND DRIER AIR SLOWLY WORKS INTO THE AREA FROM THE NORTH.
CIGS EXPECTED TO FALL INTO THE MVFR/IFR RANGE DURING THE OVERNIGHT
HRS WITH VERY LITTLE IMPROVEMENT DURING THE DAY SATURDAY. TIGHT
PRESSURE GRADIENT BEHIND THE COLD FRONT WILL KEEP NLY WINDS AROUND
10 KTS WITH A FEW HIGHER GUSTS BUT SPEEDS SHOULD DIMINISH SOMEWHAT
SATURDAY AS A SFC HIGH BUILDS SWD AND THE PRESSURE GRADIENT
RELAXES. /09/
&&
.PREV DISCUSSION... /ISSUED 348 PM CDT FRI SEP 12 2014/
DISCUSSION...
OUR WEAK COLD FRONT REMAINS STATIONARY JUST S OF THE I-20 CORRIDOR
OF E TX/N LA THIS AFTERNOON...WITH A LARGE SUCKER HOLE RECENTLY
OPENING UP ACROSS NW LA. TEMPS IN THESE AREAS HAVE WARMED INTO THE
LOWER/MID 80S THIS AFTERNOON...BUT TEMPS REMAIN MUCH COOLER UNDER
THE LOW STRATUS FARTHER W AND N. AS EXPECTED...SCT CONVECTION HAS
DEVELOPED ALONG THE FRONTAL ZONE OVER DEEP E TX...WITH THE WEAK
SEABREEZE APPROACHING THIS AREA AS WELL AS WCNTRL LA FROM SE TX/SW
LA. BELIEVE THAT THIS CONVECTION WILL CONTINUE THROUGH A PORTION
OF THIS EVENING BEFORE DIMINISHING WITH THE LOSS OF
HEATING/INSTABILITY...WITH THE FRONTAL BNDRY EXPECTED TO SLOWLY
DRIFT BACK S ACROSS THIS AREA AND THE SRN SECTIONS OF NCNTRL LA
THIS EVENING/OVERNIGHT. THE HRRR AND TO SOME EXTENT...THE 12Z WRF
DOES INDICATE THE ONGOING CONVECTION POSSIBLY BUILDING BACK A
LITTLE FARTHER NNE TO NEAR/JUST S OF THE I-20 CORRIDOR OF E TX/NW
LA THIS EVENING...WITH ONLY ISOLATED -SHRA EXPECTED FARTHER N
CLOSER TO THE WEAK 850MB TROUGH AS IT REMAINS JUST N OF THE REGION
OVER SE OK/WRN AND CNTRL AR. DID MAINTAIN HIGH CHANCE POPS FOR
AREAS NEAR/S OF THE FRONT THIS EVENING...LOWERING POPS A TAD LATE
AS THE CONVECTION SHOULD WANE ONCE OVERALL FORCING WEAKENS. SHOULD
SEE A WIDE RANGE IN MIN TEMPS OVERNIGHT GIVEN THE SHALLOW NATURE
OF THE POST-FRONTAL AIR MASS...WITH TEMPS POSSIBLY FALLING INTO
THE UPPER 50S OVER SE OK/SW AR.
THE WEAK COLD FRONT IS EXPECTED TO NEAR THE COAST AROUND 12Z
SATURDAY...WITH THE POST-FRONTAL STRATUS HOLDING TOUGH THROUGH THE
DAY. GIVEN THE DEPTH OF THE MOISTURE IN PLACE...DID INSERT SLIGHT
CHANCE POPS AREAWIDE SATURDAY AS ANY WEAK FORCING WILL EASILY
RESULT IN -SHRA DEVELOPMENT...WITH DAYTIME TEMPS ONLY RISING 10
DEGREES OR SO FROM THE MORNING LOWS. THE LOW STRATUS SHOULD BEGIN
TO SLOWLY LIFT SUNDAY...POSSIBLY SCATTERING OUT IN THE AFTERNOON
OVER PORTIONS OF THE REGION. THIS SHOULD RESULT IN MODERATING
TEMPS...ALTHOUGH SFC RIDGING IN PLACE WILL MAINTAIN ABNORMALLY LOW
DEWPOINTS AND COMFORTABLE RH/S FOR THIS TIME OF YEAR. SHOULD BEGIN
TO SEE A RETURN OF HIGHER RH/S BY TUESDAY AS THE BROAD UPPER LEVEL
LOW/TROPICAL WAVE...NOW OVER SRN FL...BEGINS TO SHIFT W ACROSS THE
GULF OF MX THIS WEEKEND AND POSSIBLY IMPACT THE TX COAST.
ATTM...ENOUGH SHEAR ALOFT SHOULD KEEP THIS SYSTEM FROM
INTENSIFYING THIS WEEKEND AND EARLY NEXT WEEK...ALTHOUGH IT WILL
HELP ENHANCE THE SEABREEZE AS IT MOVES INLAND ACROSS SE AND DEEP E
TX/SRN AND CNTRL LA TUESDAY. IN ADDITION...A SHORTWAVE IN THE NW
FLOW ALOFT WILL DROP SE ACROSS THE REGION TUESDAY AS WELL...WHICH
COULD FURTHER ENHANCE FORCING OVER THE SRN SECTIONS OF THE REGION.
HAVE INCREASED POPS TO MID CHANCE S OF I-20 TUESDAY...WITH
CONVECTION DIMINISHING TUESDAY NIGHT/WEDNESDAY AS DRIER AIR ALOFT
MIXES SE IN WAKE OF THIS SHORTWAVE. A DRY NW FLOW LOOKS TO PERSIST
THROUGHOUT THE REMAINDER OF THE WEEK AS UPPER LEVEL RIDGING BUILDS
OVER THE DESERT SW AND THE ROCKIES. TEMPS SHOULD BE NEAR CLIMO
THROUGH THE PERIOD AS WELL.
PRELIMS TO FOLLOW BELOW...
15
&&
.PRELIMINARY POINT TEMPS/POPS...
SHV 65 76 61 85 66 / 30 20 10 10 10
MLU 65 77 61 84 65 / 30 20 10 10 10
DEQ 59 71 57 79 62 / 30 20 10 10 10
TXK 60 72 58 81 63 / 30 20 10 10 10
ELD 61 74 57 81 62 / 30 20 10 10 10
TYR 63 74 61 85 68 / 40 20 10 10 10
GGG 65 75 61 85 66 / 40 20 10 10 10
LFK 69 80 64 88 68 / 50 30 10 10 10
&&
.SHV WATCHES/WARNINGS/ADVISORIES...
AR...NONE.
LA...NONE.
OK...NONE.
TX...NONE.
&&
$$
09
AREA FORECAST DISCUSSION
NWS SHREVEPORT LA
1245 PM CDT THU SEP 11 2014
.AVIATION...
COLD FRONT IS WRAPPING THE OUACHITAS AND DEEP CONVECTION REMAINS
NORTH OF I-30 WITH AN OUTFLOW FROM AR INTO I-20 OF LA DVLPG SMALL
CONVECTIVE ELEMENTS. HRRR MODEL SHOWING INCREASING COVERAGE AND
INTENSITY ALONG I-20 INTO THE HEAT OF THE AFTERNOON. VCTS FOR MANY
CITES WITH AMENDMENTS TO COME AS THE THREAT UNFOLDS. SFC WINDS
LIGHT SW AND SHIFTING TO N BEHIND OUTFLOW FOR KTXK/KELD AND SOON
FOR KSHV. ALOFT...SHV VAD...LOW LEVEL VEERING FROM SW THIS AM TO NW
THIS EARLY PM. FROPA WILL BE DURING THIS CYCLE WITH NE SFC WINDS.
&&
.PREV DISCUSSION... /ISSUED 931 AM CDT THU SEP 11 2014/
UPDATE...
HAVE UPDATED THE FORECAST TO MENTION HEAVY RAINFALL POSSIBLE IN
THE AREAS ALONG AND NEAR THE I-30 CORRIDOR. WPC HAS OUTLOOKED THE
AREA FOR HEAVY RAINFALL AND FLASH FLOODING LIKELY...NEW FORECAST
IS ALREADY OUT...
&&
.PRELIMINARY POINT TEMPS/POPS...
SHV 93 73 88 65 83 / 40 40 50 30 20
MLU 95 72 88 65 86 / 40 30 50 40 20
DEQ 84 68 77 60 77 / 60 50 70 20 10
TXK 90 71 81 63 80 / 60 50 60 30 10
ELD 91 70 86 63 81 / 40 40 60 30 20
TYR 91 73 86 64 82 / 40 50 50 20 20
GGG 94 73 88 64 82 / 40 40 50 30 20
LFK 95 74 89 69 83 / 20 30 50 40 30
&&
.SHV WATCHES/WARNINGS/ADVISORIES...
AR...NONE.
LA...NONE.
OK...NONE.
TX...NONE.
&&
$$
24
AREA FORECAST DISCUSSION...UPDATED
NWS PITTSBURGH PA
854 PM EDT FRI SEP 12 2014
.SYNOPSIS...
COOL WEATHER PATTERN FOR MUCH OF THE FORECAST. SHOWERS WILL MOVE
THROUGH SATURDAY MORNING.
&&
.NEAR TERM /THROUGH SATURDAY/...
HAVE ADJUSTED CLOUD COVER AND TEMPS FOR OVERNIGHT. DRIER AIR
CONTINUES TO NOSE IN FROM THE EAST...SO CLOUDS WILL BE A LITTLE
TRICKY EARLY IN THE FORECAST PERIOD. CLOUDS WILL BE ON THE
INCREASE OVER THE CLEAR AREAS LATER TONIGHT AS THE NEXT SYSTEM
SLOWLY MOVES IN FROM THE SOUTH AND WEST.
PREVIOUS DISCUSSION FOLLOWS AND IS STILL LARGELY
APPLICABLE...CLOUDY DAY ACROSS THE PBZ CWA. MDCRS PLOT FROM PIT
CONTINUES TO SHOW A STOUT INVERSION JUST ABOVE H900.
HOWEVER...CLOUDS ARE STARTING TO ERODE A BIT FROM THE EASTERN
RIDGES...GARRETT AND TUCKER COUNTIES IN PARTICULAR ARE GETTING
SOME SUN. WHILE THIS SLOW TREND SHOULD CONTINUE FOR A FEW HOURS
WITH LBE AND DUJ BENEFITING A BIT...I AM DUBIOUS THAT MUCH CLOUD
BREAKUP WILL OCCUR FROM PIT ON WEST. RAP SOUNDINGS CONCUR WITH
THIS. IN ANY EVENT...AREAS THAT CLEAR WILL START TO SEE MID CLOUDS
INCREASE THIS EVENING IN SW FLOW ALOFT AHEAD OF NEXT SYSTEM.
MODELS ARE IN GOOD AGREEMENT ON THE SCENARIO. FAIRLY SHARP H500
SHORTWAVE WILL MOVE ACROSS THE GREAT LAKES TONIGHT AND INTO SOUTHERN
QUEBEC BY 00Z SUNDAY. A WEAK SURFACE WAVE WILL FORM ALONG THE FRONT
FROM YESTERDAY AND MOVES NORTHEAST THROUGH THE CAROLINAS TONIGHT.
IN OUR CWA...INVERTED TROUGHING AT THE SURFACE WILL HELP TO PULL
DEEPER MOISTURE BACK NORTHWARD...ESPECIALLY EAST OF THE OHIO RIVER.
PWATS RISE TO AROUND 1.5 INCHES FOR A SHORT TIME SOUTH OF PIT LATE
TONIGHT. POPS LITTLE CHANGED FROM PREVIOUS SHIFT...WITH LIKELY
VALUES EAST OF HLG/PIT/FKL AND LESSER TO THE WEST. LOOKING FOR A
QUARTER TO A HALF INCH OF RAIN AT MOST ALONG THE RIDGES. THUNDER
NOT EXPECTED.
SHORTWAVE TROUGH AXIS QUICKLY ROTATES THROUGH AFTER 12Z
SATURDAY...WHICH WILL SHUNT THE DEEP MOISTURE EASTWARD BY
MID-AFTERNOON. A FEW SHOWERS MAY LINGER IN LOW LEVEL NW FLOW...BUT
EXPECTING ALL RAIN TO WRAP UP BY 00Z SUNDAY...WHEN A SURFACE HIGH
BEGINS TO ARRIVE FROM THE WEST.
BELOW SEASONAL TEMPERATURES WILL CONTINUE.
&&
.SHORT TERM /SATURDAY NIGHT THROUGH MONDAY/...
BLDG HIGH PRES WL BRING DRY WEA THRU ERLY MON. THE HIGH WL SHIFT E
MON AFTN...WITH INCRG CLDS AHD OF THE NXT APCHG SHRTWV. TEMPS WL
CONT TO AVG BLO SEASONAL LVLS.
&&
.LONG TERM /MONDAY NIGHT THROUGH FRIDAY/...
THE ADVNG SHRTWV IS EXPD TO SPAWN SHWRS MONDAY NGT AND EARLY TUES.
SFC HIGH PRES...UNDR BROAD ERN CONUS TROFG...IS THEN FORECAST TO
MAINTAIN DRY...BUT SEASONABLY COOL WEATHER FOR THE RMNDR OF THE
LONG TERM PD. LONG TERM TEMPS WERE FORECAST USING HPC GUIDANCE...
TWEAKED UPWARD VIA GFS MOS TRENDS.
&&
.AVIATION /01Z SATURDAY THROUGH WEDNESDAY/...
MVFR CIGS BLANKET ALL PORTS BUT MGW AND LBE. CLEARING LINE IS
TRYING TO EDGE ITS WAY WESTWARD...SO AGC AND PIT MAY SEE SOME
LESSENING OF CLOUD COVER BEFORE THE MVFR CIG DECK TO THE WEST
BEGINS TO MOVE EASTWARD AHEAD OF NEXT SYSTEM. FORECAST WILL MIRROR
THIS TREND OVERNIGHT. LIGHT SHOWERS WILL MOVE IN TOWARD
DAWN...DON`T EXPECT MANY RESTRICTIONS AND RAINFALL MAY AVOID ZZV.
SYSTEM QUICKLY MOVES EASTWARD SATURDAY MORNING...ALLOWING FOR
IMPROVEMENT IN CONDITIONS FROM WEST TO EAST. WITH THE EXCEPTION OF
NORTHERN PORTS...RETURN TO VFR CONDITIONS IS ANTICIPATED.
OUTLOOK...THURSDAY NIGHT THROUGH TUESDAY...
NEXT FRONTAL SYSTEM WITH POSSIBLE RESTRICTIONS ARRIVES MONDAY
NIGHT INTO TUESDAY.
&&
.PBZ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
OH...NONE.
PA...NONE.
WV...NONE.
&&
$$
AREA FORECAST DISCUSSION...UPDATED
NWS PITTSBURGH PA
721 PM EDT FRI SEP 12 2014
.SYNOPSIS...
COOL WEATHER WILL CARRY THROUGH MUCH OF THE NEXT SEVEN DAYS. LOW
PRESSURE PASSING SATURDAY BRINGS THE CHANCE FOR SHOWERS...OUTSIDE
EASTERN OHIO. AFTER A PERIOD OF DRY WEATHER THANKS TO HIGH
PRESSURE...THE NEXT COLD FRONT IS PREDICTED TO CROSS TUESDAY INTO
WEDNESDAY.
&&
.NEAR TERM /THROUGH SATURDAY/...
SKIES HAVE GENERALLY CLEARED IN THE RIDGES AND IN ALL POINTS TO
THEIR EAST. AS LOW LEVEL FLOW AS TURNED A BIT MORE EASTERLY...A
HINT OF DOWNSLOPE MAY ERODE THE EASTERN EDGE OF THE STRATUS SHIELD
PRIOR TO MID-CLOUD INCREASING. SKY GRIDS WERE ADJUSTED
ACCORDINGLY...HOWEVER ONLY THE EASTERN FRINGE OF THE FORECAST AREA
IS LIKELY TO BENEFIT FROM ANY SCATTERING OUT/CLEARING...WHILE THE
STRATUS SHOULD HOLD IN THE MAJORITY OF THE AREA UNTIL THE ARRIVAL
OF A DEEPER CLOUD SHIELD. FRIES
PREVIOUS DISCUSSION FOLLOWS AND IS STILL LARGELY
APPLICABLE...CLOUDY DAY ACROSS THE PBZ CWA. MDCRS PLOT FROM PIT
CONTINUES TO SHOW A STOUT INVERSION JUST ABOVE H900.
HOWEVER...CLOUDS ARE STARTING TO ERODE A BIT FROM THE EASTERN
RIDGES...GARRETT AND TUCKER COUNTIES IN PARTICULAR ARE GETTING
SOME SUN. WHILE THIS SLOW TREND SHOULD CONTINUE FOR A FEW HOURS
WITH LBE AND DUJ BENEFITING A BIT...I AM DUBIOUS THAT MUCH CLOUD
BREAKUP WILL OCCUR FROM PIT ON WEST. RAP SOUNDINGS CONCUR WITH
THIS. IN ANY EVENT...AREAS THAT CLEAR WILL START TO SEE MID CLOUDS
INCREASE THIS EVENING IN SW FLOW ALOFT AHEAD OF NEXT SYSTEM.
MODELS ARE IN GOOD AGREEMENT ON THE SCENARIO. FAIRLY SHARP H500
SHORTWAVE WILL MOVE ACROSS THE GREAT LAKES TONIGHT AND INTO SOUTHERN
QUEBEC BY 00Z SUNDAY. A WEAK SURFACE WAVE WILL FORM ALONG THE FRONT
FROM YESTERDAY AND MOVES NORTHEAST THROUGH THE CAROLINAS TONIGHT.
IN OUR CWA...INVERTED TROUGHING AT THE SURFACE WILL HELP TO PULL
DEEPER MOISTURE BACK NORTHWARD...ESPECIALLY EAST OF THE OHIO RIVER.
PWATS RISE TO AROUND 1.5 INCHES FOR A SHORT TIME SOUTH OF PIT LATE
TONIGHT. POPS LITTLE CHANGED FROM PREVIOUS SHIFT...WITH LIKELY
VALUES EAST OF HLG/PIT/FKL AND LESSER TO THE WEST. LOOKING FOR A
QUARTER TO A HALF INCH OF RAIN AT MOST ALONG THE RIDGES. THUNDER
NOT EXPECTED.
SHORTWAVE TROUGH AXIS QUICKLY ROTATES THROUGH AFTER 12Z
SATURDAY...WHICH WILL SHUNT THE DEEP MOISTURE EASTWARD BY
MID-AFTERNOON. A FEW SHOWERS MAY LINGER IN LOW LEVEL NW FLOW...BUT
EXPECTING ALL RAIN TO WRAP UP BY 00Z SUNDAY...WHEN A SURFACE HIGH
BEGINS TO ARRIVE FROM THE WEST.
BELOW SEASONAL TEMPERATURES WILL CONTINUE.
&&
.SHORT TERM /SATURDAY NIGHT THROUGH MONDAY/...
BLDG HIGH PRES WL BRING DRY WEA THRU ERLY MON. THE HIGH WL SHIFT E
MON AFTN...WITH INCRG CLDS AHD OF THE NXT APCHG SHRTWV. TEMPS WL
CONT TO AVG BLO SEASONAL LVLS.
&&
.LONG TERM /MONDAY NIGHT THROUGH FRIDAY/...
THE ADVNG SHRTWV IS EXPD TO SPAWN SHWRS MONDAY NGT AND EARLY TUES.
SFC HIGH PRES...UNDR BROAD ERN CONUS TROFG...IS THEN FORECAST TO
MAINTAIN DRY...BUT SEASONABLY COOL WEATHER FOR THE RMNDR OF THE
LONG TERM PD. LONG TERM TEMPS WERE FORECAST USING HPC GUIDANCE...
TWEAKED UPWARD VIA GFS MOS TRENDS.
&&
.AVIATION /23Z FRIDAY THROUGH WEDNESDAY/...
MVFR CIGS BLANKET ALL PORTS BUT MGW AND LBE. CLEARING LINE IS
TRYING TO EDGE ITS WAY WESTWARD...SO AGC AND PIT MAY SEE SOME
LESSENING OF CLOUD COVER BEFORE THE MVFR CIG DECK TO THE WEST
BEGINS TO MOVE EASTWARD AHEAD OF NEXT SYSTEM. FORECAST WILL MIRROR
THIS TREND OVERNIGHT. LIGHT SHOWERS WILL MOVE IN TOWARD
DAWN...DON`T EXPECT MANY RESTRICTIONS AND RAINFALL MAY AVOID ZZV.
SYSTEM QUICKLY MOVES EASTWARD SATURDAY MORNING...ALLOWING FOR
IMPROVEMENT IN CONDITIONS FROM WEST TO EAST. WITH THE EXCEPTION OF
NORTHERN PORTS...RETURN TO VFR CONDITIONS IS ANTICIPATED.
OUTLOOK...THURSDAY NIGHT THROUGH TUESDAY...
NEXT FRONTAL SYSTEM WITH POSSIBLE RESTRICTIONS ARRIVES MONDAY
NIGHT INTO TUESDAY.
&&
.PBZ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
OH...NONE.
PA...NONE.
WV...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS WAKEFIELD VA
359 PM EDT THU SEP 11 2014
.SYNOPSIS...
COLD FRONT WILL CROSS THE REGION THIS EVENING AND INTO THE
OVERNIGHT. THE FRONT WILL STALL OVER NORTH CAROLINA THROUGH THE
WEEKEND. FRONTAL BOUNDARY WILL REMAIN ALONG THE SOUTHEAST COAST
INTO EARLY NEXT WEEK AS HIGH PRESSURE BUILDS TO THE NORTH.
&&
.NEAR TERM /UNTIL 6 AM FRIDAY MORNING/...
LATEST RADAR MOSAIC DEPICTS A NARROW BAND OF
SHOWERS/THUNDERSTORMS OVER THE HIGHER TERRAIN OF WRN VA. COLD
FRONT LOCATED NOT FAR BEHIND OVER THE CNTRL APPALACHIANS. ISOLATED
SHOWERS HAVE DEVELOPED JUST WEST OF THE LOCAL AREA...BUT QUICKLY
DISSIPATED AS THEY PROPAGATED EWD THANKS TO SUBSIDENCE ALOFT.
EXPECT THIS TREND TO CONTINUE UNTIL THE COLD FRONT REACHES THE
LOCAL AREA LATE THIS AFTERNOON-EARLY THIS EVENING.
WEAK UPPER WAVE VISIBLE ON WATER VAPOR WILL PUSH INTO THE REGION
THIS EVENING AS THE COLD FRONT SLOWLY CROSSES THE LOCAL AREA.
PRECIP CHANCES THIS EVENING WILL BE TIED TO THE WEAKENING
FRONT/CONVERGENCE ZONE. SHORTWAVE WILL HELP SUPPORT SOME MODEST
UVM...BUT WITH THE BEST DYNAMICS/FLOW REMAINING WELL NORTH...UPPER
LEVEL FORCING WILL BE RATHER UNIMPRESSIVE. HI-RES GUIDANCE
CONTINUES TO INDICATE SCT SHOWERS/THUNDERSTORMS ALONG/IN ADVANCE
OF THE FRONT WITH THE BEST COVERAGE OVER THE N AND NE. SOME
LOCATIONS IN THE SW COULD EVEN REMAIN DRY. UPSTREAM PWATS AROUND 2
INCHES WILL SPREAD INTO THE REGION IN WLY FLOW...WITH MOISTURE
EXTENDING UP TO 300MB. UNFAVORABLE OVERNIGHT FRONTAL TIMING AND
WEAK SHEAR WILL ONLY RESULT IN SLIGHT CHANCE-CHANCE THUNDER.
POTENTIAL EXISTS OVER THE PIEDMONT FOR GUSTY WINDS AS TIMING AND
INSTABILITY IS BETTER AND BUFR SOUNDINGS INDICATED DRY LOW LEVELS.
LOCALLY HEAVY RAINFALL IS ALSO POSSIBLE DUE TO HIGH PWATS AND WEAK
FLOW. FRONTAL TIMING AND CLOUDS WILL RESULT IN MILD OVERNIGHT
TEMPS...GENERALLY IN THE MID-UPPER 60S. COOLER IN THE NW IF SKIES
CAN CLEAR BEHIND THE FRONT.
&&
.SHORT TERM /6 AM FRIDAY MORNING THROUGH SUNDAY/...
UNSETTLED/WET WEATHER PATTERN EXPECTED THROUGH THE WEEKEND AS
TEMPS REMAIN BELOW NORMAL.
COLD FRONT PUSHES THRU THE AREA THRU FRI MORNING...STALLING
ACROSS NC AS FLOW ALOFT REMAINS SWLY. A POTENT UPPER SHORTWAVE
OVER THE UPPER MIDWEST WILL EJECT QUICKLY EWD AS A STRONG SPEED
MAX ROUNDS THE BASE OF THE TROUGH. SUBTROPICAL HIGH GETS SHOVED
SWD OVER THE GULF STATES/NRN GULF...BUT VERY LITTLE CHANGE IN MID
LEVEL HEIGHTS OVER THE LOCAL AREAL. SFC HIGH PRESSURE BUILDS OVER
SE CANADA/NE US WITH A RIDGE AXIS EXTENDING SWD INTO THE LOCAL
AREA. STILL SOME UNCERTAINTY AS TO WHERE THE FRONT WILL
STALL...BUT ATTM IT APPEARS IT WILL BE JUST SOUTH OF THE LOCAL
AREA. BEST CHANCES FOR MEASURABLE RAIN WILL BE TIED TO THE WEAK
FRONTAL BOUNDARY AND HIGH PWAT AXIS. HOWEVER...MDLS DIFFER ON THE
AMOUNT OF MOISTURE OVER THE LOCAL AREA...WHICH COMBINED WITH WEAK
WAVES IN SWLY FLOW MAY BE ENOUGH FOR SHOWERS FRI. WILL KEEP BETTER
POPS CLOSE TO THE FRONT...BUT WILL MAINTAIN LOW END CHANCE POPS
NWD INTO CNTRL VA. HYBRID WEDGE SETUP WILL KEEP SKIES CLOUDY AS
WINDS WILL BE FROM THE N-NE. CLOUDS/POSSIBLE PRECIP WILL PREVENT
TEMPS FROM REACHING THEIR FULL POTENTIAL WITH HIGHS GENERALLY IN
THE MID 70S.
SHORTWAVE PROPAGATES EWD OVER THE GREAT LAKES INTO SE CANADA SAT.
A WAVE OF LOW PRESSURE IS PROGGED TO DEVELOP ALONG THE FRONT OVER
THE TN VALLEY WITH ANOTHER AREA OF LOW PRESSURE DEVELOPING OFF THE
NC COAST. THE INLAND LOW WILL BEGIN TO LIFT NEWD IN AMPLIFYING
FLOW...LIFTING THE FRONT NWD. TWO DISTINCT AREAS OF PRECIP
EXPECTED TO DEVELOP FRI NIGHT-SAT MORNING...WITH THE FIRST LIFTING
OVER THE CNTRL APPALACHIANS AND THE OTHER REMAINING OVER ERN NC
AND OFFSHORE. BUT AS THE LOW QUICKLY LIFTS NWD INTO NEW
ENGLAND...OVERRUNNING MOISTURE/PRECIP OVERSPREAD MUCH OF THE LOCAL
AREA FROM THE SOUTH AND WEST. HAVE INCREASED POPS TO LIKELY AS
BETTER AGREEMENT IN THE MODELS LENDS TO HIGHER CONFIDENCE. PWATS
RETURN TO AROUND 2+ INCHES...AND MOISTURE EXTENDS WELL ABOVE
0C...SO LOCALLY HEAVY RAINFALL IS POSSIBLE. SHORTWAVE PUSHES OFF
THE NE COAST SAT NIGHT INTO SUN MORNING AS THE COASTAL LOW LIFTS
NEWD AWAY FROM THE COAST. HOWEVER...FLOW REMAINS SWLY OVER THE
LOCAL AREA WITH THE BOUNDARY REMAINING ALONG THE COAST. HIGH
PRESSURE WILL ALSO BUILD OVER NEW ENGLAND IN WAKE OF LOW
PRESSURE...REINFORCING THE HYBRID CAD OVER THE LOCAL AREA. NLY
FLOW WILL AGAIN RESULT IN MOSTLY CLOUDY-CLOUDY SKIES. INLAND BUFR
SOUNDINGS INDICATE SOME CLEARING OVER THE PIEDMONT. BEST RAINFALL
CHANCES TRANSITION TO ERN VA SAT NIGHT INTO SUN WITH THE BEST
CHANCES FOR PRECIP TRANSFERRING TO SE VA/NE NC SUN. TRENDED QPF
TOWARD ENSEMBLE MEAN GUIDANCE...WITH QPF AMOUNTS THIS WEEKEND
RANGING FROM AROUND ONE QUARTER INCH NE TO AN INCH SOUTH.
HOWEVER...THERE ARE SOME OUTLIERS INDICATING THAT MORE RAINFALL
MAY FALL. BASED ON PWATS OF +2 STD DEV AND WEAK FLOW...LOCALLY
HEAVY RAINFALL IS EXPECTED WITH SOME AREAS RECEIVING UPWARDS OF 2+
INCHES. HIGHS AGAIN SUN IN THE LOW-MID 70S.
&&
.LONG TERM /SUNDAY NIGHT THROUGH THURSDAY/...
DESPITE THE TIME OF THE YEAR...WILL LEAN TOWARD THE WETTER ECMWF
GIVEN THE FORECASTED UPR LVL PATTERN NEXT WEEK. FRONTAL BOUNDARY
REMAINS SOUTH OF THE REGION TO START OFF THE PERIOD WITH SEVERAL
AREAS OF LOW PRESSURE MOVING NORTH ALONG IT MONDAY AND TUESDAY
BASICALLY KEEPING CLOUDS AND PERIODIC CHCS FOR RAIN. FRONTAL BNDRY
MAY ACTUALLY SNAKE BACK NORTH AS A WARM FRONT TUESDAY SO WENT AHEAD
AND ADDED THUNDER ACROSS SERN HALF OF FA THEN. CLOUDS / PCPN KEEPS
TMPS BLO NORMAL WITH HIGHS BOTH DAYS IN THE 70S. LOWS U50S-U60S.
TRAILING COLD FRONT PUSHES OFFSHORE TUES NIGHT AND ERLY WED AS THE
1020MB CANADIAN HIGH PRS BUILDS EAST. GUID WANTS TO STALL THIS BNDRY
IVOF THE GULF STREAM ONCE AGAIN KEEPING ADDNTL CLOUDINESS AND SCT
SHWRS ALONG THE MID ATLNTC COASTAL SECTIONS WED INTO THU. COOLER
WITH HIGH WED / THU 70-75. LOWS IN THE 50S XCPT 60S COASTAL AREAS.
&&
.AVIATION /20Z THURSDAY THROUGH TUESDAY/...
VFR CONDITIONS PREVAIL AHEAD OF A COLD FRONT. THE FRONT WILL MOVE
ACROSS THE AREA THIS EVENING. ACCOMPANYING THE FRONT WILL BE
SCATTERED SHOWERS AND TSTMS. SEVERAL MODELS WEAKEN THESE STORMS AS
THE CROSS THE AREA TONIGHT. THE HRRR TRIES TO BRING SOME THROUGH
AFTER 00Z TO ABOUT 03Z. WOULD EXPECT AT LEAST SOME SHOWERS THAT
TIME FRAME AND POSSIBLY A TSTM. THE HEAVIEST SHOWERS COULD BRIEFLY
BRING MVFR CIGS OR VSBY. AFTER THE FRONT PASSES WINDS WILL SHIFT
TO THE NORTHEAST. WINDS ALOFT WILL REMAIN SOUTHWEST AND CAUSE THE
FRONT TO STALL IN NORTHEAST NORTH CAROLINA. THIS WILL CAUSE CLOUDS
TO LINGER ACROSS THE AREA LATE TONIGHT AND THROUGH FRIDAY. THERE
IS A GOOD CHANCE FOR MVFR CIGS FROM PHF SOUTHEAST. COULD EVEN BE
SOME BRIEF IFR CIGS ON FRIDAY MORNING. THERE WILL ALSO BE THE
CHANCE OF SHOWERS AGAIN ON FRIDAY.
OUTLOOK...THE FRONT REMAINS STATIONARY IN NE NC WITH WEAK WAVES
OF LOW PRESSURE MOVING ALONG IT INTO THE WEEKEND. THIS WILL CAUSE
PERIODS OF PCPN AND POSSIBLE MVFR AND PATCHY IFR SATURDAY THROUGH
SUNDAY.
&&
.MARINE...
MODELS CONTINUE TO SHOW A SEVERAL HOUR PERIOD OF MINIMAL SCA WINDS
BEHIND A COLD FRONT LATE TONIGHT AND FRI. TWEEKED TIMING OF SCA`S
FOR THE BAY A BIT AND ALSO ADDED THE LOWER JAMES RIVER TO THE MIX
FRI MORNING. WENT AHEAD WITH A MINIMAL SCA FOR NRN CSTL WTRS FRI
MORNING AS WELL. DATA SUGGESTS GUSTS TO 25 KTS PSBL N OF PARRAMORE
ISLAND FOR A FEW HRS. SEAS AVGG 3-4 FT BUT CAN`T RULE OUT SOME 5
FOOTERS OUT NEAR 20 NM AT TIMES.
HIGH PRES MOVES INTO NEW ENG BY SAT...BRINGING CONTD ONSHORE (NE)
WNDS AHEAD OF NEXT LOW PRES SYS AND ITS ASSOCIATED CDFNT. THAT SYS
CROSSES THE WTRS SAT NIGHT. MODELS NOT AS BULLISH WITH THE SURGE
BEHIND THIS BNDRY...BUT WILL CONTINUE TO INDICATE ANTHR CAA SURGE
SUN MORNING GIVEN THE MODELS TEND TO UNDERFCST THESE EVENTS.
ONSHORE FLOW CONTINUES INTO EARLY NEXT WEEK BUT SPEEDS XPCTD TO
REMAIN BLO 20 KTS AS A COMPLEX SYSTEM OF LOW PRESSURE SYSTMS AFFECT
THE MID ATLNTC REGION.
&&
.TIDES/COASTAL FLOODING...
GIVEN A FORECAST OF LEVELS RIGHT ARND MINOR FLOODING THRESHOLDS
FOR THIS AFTRNS HIGH TIDE...WENT AHEAD AND ISSUED ANTHR CSTL FLOOD
ADVSRY FOR THE CHES BAY SIDE OF THE LWR MD ERN SHORE BTWN 18Z-00Z.
&&
.AKQ WATCHES/WARNINGS/ADVISORIES...
MD...MODERATE RIP CURRENT RISK UNTIL 8 PM EDT THIS EVENING FOR
MDZ025.
COASTAL FLOOD ADVISORY UNTIL 8 PM EDT THIS EVENING FOR
MDZ021>023.
NC...MODERATE RIP CURRENT RISK UNTIL 8 PM EDT THIS EVENING FOR
NCZ102.
VA...MODERATE RIP CURRENT RISK UNTIL 8 PM EDT THIS EVENING FOR
VAZ098>100.
MARINE...SMALL CRAFT ADVISORY FROM 7 AM TO 4 PM EDT FRIDAY FOR ANZ632-
634.
SMALL CRAFT ADVISORY FROM 6 AM TO NOON EDT FRIDAY FOR ANZ630-
631.
SMALL CRAFT ADVISORY FROM 6 AM TO 1 PM EDT FRIDAY FOR ANZ638.
SMALL CRAFT ADVISORY FROM 6 AM TO 2 PM EDT FRIDAY FOR ANZ650-
652.
&&
$$
SYNOPSIS...SAM
NEAR TERM...SAM
SHORT TERM...SAM
LONG TERM...MPR
AVIATION...LSA/JAB
MARINE...MPR
TIDES/COASTAL FLOODING...
AREA FORECAST DISCUSSION
NWS WAKEFIELD VA
134 PM EDT THU SEP 11 2014
.SYNOPSIS...
A COLD FRONT OVER THE OHIO VALLEY WILL APPROACH THE MID ATLANTIC
STATES AND MOVE THROUGH THE AREA TONIGHT AND SETTLE OVER NORTH
CAROLINA FRIDAY. A LOW PRESSURE SYSTEM WILL AFFECT THE REGION
SATURDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
HIGH PRESSURE HAS PUSHED OFFSHORE THIS MORNING IN ADVANCE OF A
COLD FRONT APPROACHING FROM THE WEST. GRADIENT BTWN THESE SFC
FEATURES HAS PRODUCED SW WINDS OF 10 TO 15 MPH WITH A FEW GUSTS OF
25 MPH. MORNING STRATUS HAS ERODED WITH ONLY SOME PASSING HIGH
CLOUDS RESULTING IN PARTLY SUNNY SKIES. TEMPS HAVE ALREADY WARMED
INTO THE UPPER 70S TO LOW 80S THANKS TO SW WINDS AND INCREASING
THICKNESSES.
FOR TODAY...WATER VAPOR AND MORNING RAOB PLOTS INDICATE SHORTWAVE
ENERGY OVER THE LWR MO VALLEY THAT WILL TRACK EWD ALONG THE KY/TN
VALLEYS THRU THE DAY. COLD FRONT WILL REACH THE CNTRL APPALACHIANS
EARLY THIS EVENING. IN ADVANCE OF THE FRONT...STRONG SFC HEATING
AND SW WINDS (GUSTS TO 20 MPH) WILL PUSH TEMPS INTO THE LOW 90S
(+1 STD DEV) MOST LOCATIONS. LOW-MID 80S ALONG THE COAST. HIGH
PRESSURE ALOFT WILL NUDGE INTO THE REGION FROM THE SW
TODAY...HELPING PROVIDE SUBSIDENCE OVER THE REGION. LACK OF
APPRECIABLE FORCING/TRIGGER WILL ALSO HELP KEEP THINGS
DRY...REGARDLESS OF INCREASING MOISTURE/INSTABILITY AND POTENTIAL
HEATING/DIFFERENTIAL BOUNDARIES. MAINLY FAIR WEATHER CU TODAY
UNDER THE INVERSION...WITH MID-HIGH CLOUDS INCREASING FROM THE
WEST LATE TODAY.
PRECIP CHANCES WILL BE TIED TO THE WEAKENING FRONT/CONVERGENCE
ZONE. AFOREMENTIONED SHORTWAVE WILL LIKELY HELP SUPPLY SOME MODEST
UVM...BUT WITH THE BEST DYNAMICS/FLOW REMAINING WELL NORTH...UPPER
LEVEL FORCING WILL BE RATHER UNIMPRESSIVE. EVEN ONGOING PRECIP
OVER THE CNTRL APPALACHIANS WILL QUICKLY OUTRUN THE BETTER UPPER
LEVEL SUPPORT...LIKELY DISSIPATING AS IT REACHES THE PIEDMONT.
PRECIP CHANCES INCREASE LATE TODAY INTO THIS EVENING ACROSS THE
PIEDMONT. HI-RES GUIDANCE CONTINUES TO INDICATE SCT
SHOWERS/THUNDERSTORMS ALONG THE LINE WITH THE BEST COVERAGE OVER
THE N AND NE. SOME LOCATIONS IN THE SW COULD REMAIN DRY. UPSTREAM
PWATS AROUND 2 INCHES WILL SPREAD INTO THE REGION IN WLY
FLOW...WITH MOISTURE EXTENDING UP TO 300MB. UNFAVORABLE OVERNIGHT
FRONTAL TIMING AND WEAK SHEAR WILL ONLY RESULT IN SLIGHT CHANCE
THUNDER. POTENTIAL EXISTS OVER THE PIEDMONT FOR GUSTY WINDS AS
TIMING AND INSTABILITY IS BETTER AND BUFR SOUNDINGS INDICATED DRY
LOW LEVELS. LOCALLY HEAVY RAINFALL IS ALSO POSSIBLE DUE TO HIGH
PWATS AND WEAK FLOW. FRONTAL TIMING AND CLOUDS WILL RESULT IN MILD
OVERNIGHT TEMPS...GENERALLY IN THE MID-UPPER 60S. COOLER IN THE NW
IF SKIES CAN CLEAR BEHIND THE FRONT.
&&
.SHORT TERM /FRIDAY THROUGH SATURDAY/...
FRIDAY WILL SEE SIGNIFICANTLY COOLER TEMPERATURES DUE TO CLOUD COVER
AND A COOLER AIR MASS. PCPN WILL BE MAINLY OVER SE PORTIONS CLOSE TO
THE FRONT WITH POPS LOWERING THROUGH THE DAY FROM NORTH TO SOUTH.
FUTURE ISSUANCES MAY BE ABLE TO HAVE ADDITIONAL LOWERING OF THE POPS
NORTHERN PORTIONS. LOWERED TEMPERATURES FRIDAY WITH GENERALLY LOW TO
MID 70S EXCEPT UPR 70S TO NEAR 80 IN NORTH CAROLINA COUNTIES. CLOUD
COVER WILL RESULT IN LOW TEMPERATURES FROM THE MID 60S TO AROUND 70
SATURDAY MORNING.
AN UPPER LEVEL SHORT WAVE MOVES ACROSS THE MIDWEST AND DEVELOPS A
SURFACE LOW TO OUR WEST. THIS WILL BRING AN INCREASE IN MOISTURE AND
PCPN DURING THE DAY SATURDAY. BASICALLY HAVE 50 PERCENT POPS ACROSS
THE AREA AS THE DETAILS ARE NOT CLEAR AT THIS POINT. FUTURE
ISSUANCES WILL PROBABLY HAVE LIKELY POPS IN PORTIONS OF THE CWA.
CLOUD COVER AND PCPN WILL HOLD TEMPERATURES DOWN AND HAVE HIGHS JUST
A FEW DEGREES HIGHER THAN FRIDAY...GENERALLY MID TO UPR 70S WITH 80
DEGREE READINGS IN NORTH CAROLINA.
MINOR CHANGES WERE MADE TO THE FORECAST FOR SATURDAY NIGHT AND
SUNDAY BUT GENERALLY DRYING MOVES IN FROM THE NW FOLLOWING THE
PASSAGE OF THE SHORT WAVE. ANOTHER DAY OF BELOW NORMAL TEMPERATURES
IS EXPECTED ON SUNDAY. SEE BELOW FOR MORE DETAILS.
&&
.LONG TERM /SATURDAY NIGHT THROUGH THURSDAY/...
UPR LEVEL TROF ACROSS THE ERN US RESULTS IN A COOLER THAN NORMAL
PATTERN THROUGH THE MEDIUM RANGE PERIOD. MODELS SEEM TO AGREE THAT
THE FA WILL BE NORTH OF THE STALLED FRONTAL BOUNDARY (IVOF THE GULF
STREAM) EARLY NEXT WEEK. THE FORECAST CHALLENGE WILL BE TIMING OF
SEVERAL WAVES OF ENERGY PROGGED TO MOVE NE ALONG THIS BOUNDARY AS
CANADIAN HIGH PRESSURE (1025 MB) TRACKS EAST WHILE REMAINING NORTH
OF THE AREA.
FOLLOWED THE ECMWF WRT SYNOPTIC FEATURES WHICH FEATURES A SCNDRY
BNDRY PASSAGE SAT NIGHT / SUNDAY. KEPT CHC POPS (SHWRS) IN ATTM WITH
THE HIGHEST POPS ACROSS SRN HALF OF FA...ESPECIALLY SUNDAY. MAY
ACTUALLY DRY ACROSS NRN COUNTIES WITH SOME AFTRN SUNSHINE GIVEN
STRENGTH OF THE HIGH PRESSURE BUILDING IN FROM THE NW. LOWS SAT &
SUN NIGHTS 55-60 NORTH...M-U60S SOUTH. HIGHS SUN L-M70S.
DATA SUGGESTS BOUNDARY BEGINS TO DRIFT BACK NORTH AS A WARM FRONT
MON AND TUES...BUT CONFIDENCE ON JUST HOW FAR NORTH IT GETS IS
PROBLEMATIC ATTM. KEPT CHC POPS (SHWRS...KEEPING THUNDER OUT OF FCST
THIS FAR OUT) WITH HIGHEST POPS SOUTH ONCE AGAIN. HIGHS MON L-M70S.
LOWS MON NIGHT U50S-U60S. WARMING A BIT TUESDAY WITH HIGHS 75-80.
DRYING OUT WED WITH HIGHS M-U70S.
&&
.AVIATION /18Z THURSDAY THROUGH TUESDAY/...
VFR CONDITIONS PREVAIL AHEAD OF A COLD FRONT. THE FRONT WILL MOVE
ACROSS THE AREA THIS EVENING. ACCOMPANYING THE FRONT WILL BE
SCATTERED SHOWERS AND TSTMS. SEVERAL MODELS WEAKEN THESE STORMS AS
THE CROSS THE AREA TONIGHT. THE HRRR TRIES TO BRING SOME THROUGH
AFTER 00Z TO ABOUT 03Z. WOULD EXPECT AT LEAST SOME SHOWERS THAT
TIME FRAME AND POSSIBLY A TSTM. THE HEAVIEST SHOWERS COULD BRIEFLY
BRING MVFR CIGS OR VSBY. AFTER THE FRONT PASSES WINDS WILL SHIFT
TO THE NORTHEAST. WINDS ALOFT WILL REMAIN SOUTHWEST AND CAUSE THE
FRONT TO STALL IN NORTHEAST NORTH CAROLINA. THIS WILL CAUSE CLOUDS
TO LINGER ACROSS THE AREA LATE TONIGHT AND THROUGH FRIDAY. THERE
IS A GOOD CHANCE FOR MVFR CIGS FROM PHF SOUTHEAST. COULD EVEN BE
SOME BRIEF IFR CIGS ON FRIDAY MORNING. THERE WILL ALSO BE THE
CHANCE OF SHOWERS AGAIN ON FRIDAY.
OUTLOOK...THE FRONT REMAINS STATIONARY IN NE NC WITH WEAK WAVES
OF LOW PRESSURE MOVING ALONG IT INTO THE WEEKEND. THIS WILL CAUSE
PERIODS OF PCPN AND POSSIBLE MVFR AND PATCHY IFR SATURDAY THROUGH
SUNDAY.
&&
.MARINE...
SSW WNDS AHEAD OF APPROACHING CDFNT FM THE W THROUGH TDA. A BIT OF A
NOCTURNAL SURGE (TO ABT 15 KT) INVOF CNTRL BAY INTO EARLY THIS MRNG.
OTRW...CONDS RMN BLO SCA INTO TNGT. CDFNT CROSSES THE WTRS AFT
MIDNIGHT THROUGH MID MRNG FRI. XPCG A POST FNTL SURGE IN SPEEDS FM
THE N (TO LO END SCA ON THE BAY)...THERE MAY BE A SHORT PD OF SCAS
ON THE (NRN) OCN WATERS IN THE EARLY/MID MRNG AS WELL. IT IS TIME OF
YEAR FOR THESE TYPES OF SURGES TO BE A BIT MORE ROBUST THAN MDLS
FCST (COOLER/DRIER AIR SPREADING OVR WARMER WTRS). THE INCRS IN SPDS
DIMINISHES FM N TO S OVR THE WTRS IN THE AFTN/EVE HRS. SFC HI PRES
MOVES INTO NEW ENG BY SAT...BRINGING CONTD ONSHORE WNDS AHEAD OF
NEXT APPROACHES LO PRES SYS AND ITS ASSOCIATED CDFNT. THAT SYS
CROSSES THE WTRS SAT EVE...W/ PTNTLLY AN EVEN STRONGER NLY SURGE IN
ITS WAKE INTO SUN.
&&
.TIDES/COASTAL FLOODING...
GIVEN A FORECAST OF LEVELS RIGHT ARND MINOR FLOODING THRESHOLDS
FOR THIS AFTRNS HIGH TIDE...WENT AHEAD AND ISSUED ANTHR CSTL FLOOD
ADVSRY FOR THE CHES BAY SIDE OF THE LWR MD ERN SHORE BTWN 18Z-00Z.
&&
.AKQ WATCHES/WARNINGS/ADVISORIES...
MD...MODERATE RIP CURRENT RISK UNTIL 8 PM EDT THIS EVENING FOR
MDZ025.
COASTAL FLOOD ADVISORY UNTIL 8 PM EDT THIS EVENING FOR
MDZ021>023.
NC...MODERATE RIP CURRENT RISK UNTIL 8 PM EDT THIS EVENING FOR
NCZ102.
VA...MODERATE RIP CURRENT RISK UNTIL 8 PM EDT THIS EVENING FOR
VAZ098>100.
MARINE...SMALL CRAFT ADVISORY FROM 7 AM TO 3 PM EDT FRIDAY FOR ANZ632-
634.
SMALL CRAFT ADVISORY FROM 6 AM TO NOON EDT FRIDAY FOR ANZ630-
631.
&&
$$
SYNOPSIS...LSA
NEAR TERM...SAM
SHORT TERM...LSA
LONG TERM...MPR
AVIATION...LSA/JAB
MARINE...ALB
TIDES/COASTAL FLOODING...
AREA FORECAST DISCUSSION...UPDATED
NWS ST LOUIS MO
1055 PM CDT Fri Sep 12 2014
.UPDATE:
Issued at 1027 PM CDT Fri Sep 12 2014
Issued at 620 PM CDT Fri Sep 12 2014
cloud cover continues to slowly recede southeastward across north-
central Missouri. Light to moderate drizzle still continues over
much of central Missouri into southwest and central Illinois.
Light to moderate drizzle will continue over parts of central and
much of east-central - southwest illinois through early Saturday
morning. Cloud cover will slowly recede southward with time. But
will still continue to linger beyond 0900 UTC. Surface winds will
be dimishing to 5 kts after 0600 UTC. temperatures will drop intot
he upper 30s over far northeast Missouri tonight under clear
skies. Should be a fine day on Saturday with partly cloudy skies
and mild tempatures over the region as surface high pressure
builds over the area. Could reach record lows for far northeast
Missouri and again on Sunday morning for northeast through central
Missouri.
Przybylinski
&&
.SHORT TERM: (Through Tonight)
Issued at 236 PM CDT Fri Sep 12 2014
Cloud cover continues to cover the area this afternoon as stratus is
trapped under a low level inversion and mid-high level clouds are
streaming in ahead of a mid level trough. There has been some light
rain associated with the mid-level trough moving across northern
Missouri early this afternoon, but it`s coverage has been limited.
Latest runs of the RAP and HRRR still show some redevelopment of
some light rain over western Missouri this afternoon and this
evening ahead of the upper trough that will move across the CWA this
evening. Then expect clearing of the clouds from north to south
after 06Z as the upper trough moves to the east allowing subsidence
to set in. Drier air will move into the low levels as the inversion
weakens which should allow the low level clouds to move out.
Temperatures should fall close to agreeable MOS guidance for lows
once skies begin to clear with the light northeasterly winds.
Britt
.LONG TERM: (Saturday through Next Friday)
Issued at 236 PM CDT Fri Sep 12 2014
(Saturday through Monday)
Overall, mdls are in good agreement thru this period. Period begins
with a large sfc ridge settling across the region. This ridge will
keep temps around 15 degrees below seasonal average despite ample
insolation. As the ridge retreats, the approaching trof and sfc fnt
will bring another chance for precip to the region late in the
period. Some minor differences in timing are apparent among the mdl
guidance. Will keep PoPs lower except where mdls are in agreement.
(Tuesday through Friday)
Not much change from the prev forecast. Mdls remain in good
agreement overall thru the period with respect to mass fields
anyway. Sfc ridge builds into the region on Tues with precip coming
to an end Mon night. Cool temps will prevail thru mid week, tho not
as cool as this weekend. Mdls differ regarding precip chances for
late Wed into Thurs. The ECMWF is more robust with nocturnal
convection developing along a stationary fnt across the region. The
GFS would suggest height rising with the sfc ridge still holding on
into the area. Have kept PoPs low given the uncertainty forecasting
mesoscale features on day 7.
As for temps, have trended twd the warmer guidance thru the period
given heights over the region.
Tilly
&&
.AVIATION: (For the 00z TAFs through 00z Saturday Evening)
Issued at 534 PM CDT Fri Sep 12 2014
An extensive area of MVFR stratus/stratocumulus was in place
across the region at TAF issuance. Although drier air will be
working into the region overnight, there is still a lot of
moisture trapped below an inversion. This suggests that clouds
will be slow to clear even with the drier air. On the other hand,
recent satellite imagery has shown that upstream stratocu was
breaking up over IA/NE, and it is possible that cigs may clear
earlier than expected. Ceilings could fall to IFR at times
overnight until the drier air arrives. Intermittent light drizzle
or light rain may also occur over the next several hours.
Initially northerly winds will back slightly overnight then veer
tomorrow.
Specifics for KSTL: It is likely that MVFR ceilings will persist
overnight. Ceilings should rise by tomorrow morning at the latest
due to diurnal mixing and drier low-level air. Initially northerly
winds will back slightly overnight then veer tomorrow and become
easterly towards the end of the valid TAF period.
Kanofsky
&&
.CLIMATE:
Issued at 236 PM CDT Fri Sep 12 2014
Record Lows This Weekend:
STL COU UIN
13 43(1975) 33(1902) 33(1902)
14 46(1996) 40(1892) 38(1996)
&&
.LSX WATCHES/WARNINGS/ADVISORIES:
MO...NONE.
IL...NONE.
&&
$$
WFO LSX
AREA FORECAST DISCUSSION...UPDATED
NWS ST LOUIS MO
625 PM CDT Fri Sep 12 2014
.UPDATE:
Issued at 620 PM CDT Fri Sep 12 2014
Updated forecasts for much of northern and central Missouri
based on the timing of precipitation. Frontogenetical band of
rainshowers continues to slowly slide southeast as precipitation
elements move to the east-northeast at 30 to 35 mph. Did not
change much in the way of temperatures but will look closer on
temperatures in the next update. Back to fall like weather again.
Przybylinski
&&
.SHORT TERM: (Through Tonight)
Issued at 236 PM CDT Fri Sep 12 2014
Cloud cover continues to cover the area this afternoon as stratus is
trapped under a low level inversion and mid-high level clouds are
streaming in ahead of a mid level trough. There has been some light
rain associated with the mid-level trough moving across northern
Missouri early this afternoon, but it`s coverage has been limited.
Latest runs of the RAP and HRRR still show some redevelopment of
some light rain over western Missouri this afternoon and this
evening ahead of the upper trough that will move across the CWA this
evening. Then expect clearing of the clouds from north to south
after 06Z as the upper trough moves to the east allowing subsidence
to set in. Drier air will move into the low levels as the inversion
weakens which should allow the low level clouds to move out.
Temperatures should fall close to agreeable MOS guidance for lows
once skies begin to clear with the light northeasterly winds.
Britt
.LONG TERM: (Saturday through Next Friday)
Issued at 236 PM CDT Fri Sep 12 2014
(Saturday through Monday)
Overall, mdls are in good agreement thru this period. Period begins
with a large sfc ridge settling across the region. This ridge will
keep temps around 15 degrees below seasonal average despite ample
insolation. As the ridge retreats, the approaching trof and sfc fnt
will bring another chance for precip to the region late in the
period. Some minor differences in timing are apparent among the mdl
guidance. Will keep PoPs lower except where mdls are in agreement.
(Tuesday through Friday)
Not much change from the prev forecast. Mdls remain in good
agreement overall thru the period with respect to mass fields
anyway. Sfc ridge builds into the region on Tues with precip coming
to an end Mon night. Cool temps will prevail thru mid week, tho not
as cool as this weekend. Mdls differ regarding precip chances for
late Wed into Thurs. The ECMWF is more robust with nocturnal
convection developing along a stationary fnt across the region. The
GFS would suggest height rising with the sfc ridge still holding on
into the area. Have kept PoPs low given the uncertainty forecasting
mesoscale features on day 7.
As for temps, have trended twd the warmer guidance thru the period
given heights over the region.
Tilly
&&
.AVIATION: (For the 00z TAFs through 00z Saturday Evening)
Issued at 534 PM CDT Fri Sep 12 2014
An extensive area of MVFR stratus/stratocumulus was in place
across the region at TAF issuance. Although drier air will be
working into the region overnight, there is still a lot of
moisture trapped below an inversion. This suggests that clouds
will be slow to clear even with the drier air. On the other hand,
recent satellite imagery has shown that upstream stratocu was
breaking up over IA/NE, and it is possible that cigs may clear
earlier than expected. Ceilings could fall to IFR at times
overnight until the drier air arrives. Intermittent light drizzle
or light rain may also occur over the next several hours.
Initially northerly winds will back slightly overnight then veer
tomorrow.
Specifics for KSTL: It is likely that MVFR ceilings will persist
overnight. Ceilings should rise by tomorrow morning at the latest
due to diurnal mixing and drier low-level air. Initially northerly
winds will back slightly overnight then veer tomorrow and become
easterly towards the end of the valid TAF period.
Kanofsky
&&
.CLIMATE:
Issued at 236 PM CDT Fri Sep 12 2014
Record Lows This Weekend:
STL COU UIN
13 43(1975) 33(1902) 33(1902)
14 46(1996) 40(1892) 38(1996)
&&
.LSX WATCHES/WARNINGS/ADVISORIES:
MO...NONE.
IL...NONE.
&&
$$
WFO LSX
AREA FORECAST DISCUSSION
NWS ST LOUIS MO
255 PM CDT Thu Sep 11 2014
.SHORT TERM: (Through Late Tonight)
Issued at 252 PM CDT Thu Sep 11 2014
Clouds have not cleared out this afternoon even though high
pressure has begun to build into the low levels. This is because
of persistent low level inversion that the RAP is showing around
900mb. Moisture is being trapped below this inversion, so expect
these clouds to persist into the night. Drizzle may redevelop over
the area toward morning. Temperatures did not climb much today and
do not have far to fall tonight to reach agreeable MOS guidance
for lows.
Britt
.LONG TERM: (Friday through Next Thursday)
Issued at 252 PM CDT Thu Sep 11 2014
Next shortwave to continue sliding southeast into forecast area on
Friday. Models in good agreement on timing and precipitation
associated with it. Will see isolated/widely scattered showers
develop and spread southeast across forecast area during the day
on Friday exiting late Friday evening. QPF amounts will be rather
light with best chances along and north of I-70. As for
temperatures, to remain well below normal with highs only in the
upper 50s to upper 60s. Lows Friday night will be in the low 40s
to low 50s.
Then on Saturday, strong ridge of high pressure to build in and
skies to clear out. Despite the sunshine, it will continue to feel
like fall with high temperatures only in the 60s and lows Saturday
night in the 40s.
By Sunday, surface ridge begins to move off to the east allowing
temperatures to slowly moderate. Highs will be in the upper 60s to
low 70s. Then Sunday night the next weather system to approach the
region with showers developing and spread southeast through region
Sunday night through Monday night. Frontal boundary to stall out
just south of forecast area early Tuesday morning with weak surface
ridging building in. Could see some lingering isolated/scattered
showers through Wednesday night for western and southern portions of
the area. As for temperatures, highs will be in the 70s and lows in
the 50s through next Thursday.
Byrd
&&
.AVIATION: (For the 18z TAFs through 18z Friday Afternoon)
Issued at 1226 PM CDT Thu Sep 11 2014
Expect mainly MVFR conditions to persist through the rest of the
TAF period. Current ceilings are expected to improve to above 2000
feet this afternoon, though the are expected to remain below 3000
feet through the night. Ceilings are expected to fall below 2000
feet with some IFR conditions possible between 08-16Z as drizzle
redevelops at the terminals. Conditions will then improve again by
mid morning Friday. Winds will be north to northeast and and
remain under 10kts.
Specifics for KSTL: Expect MVFR ceilings to persist through the
period, with bases increasing above 2000ft this afternoon.
Ceilings will fall back below 2000ft between 09-15Z with -dz
redeveloping at the terminal. Improvement is then expected after
mid morning Friday.
Britt
&&
.LSX WATCHES/WARNINGS/ADVISORIES:
MO...NONE.
IL...NONE.
&&
$$
WFO LSX
AREA FORECAST DISCUSSION...UPDATED AVIATION
NWS ST LOUIS MO
1227 PM CDT Thu Sep 11 2014
.UPDATE:
Issued at 1059 AM CDT Thu Sep 11 2014
Mainly cloudy skies are expected the rest of the afternoon. The
latest RAP soundings are showing moisture being trapped below a
inversion at 900mb. This will keep temperatures from climbing much
this afternoon given the clouds and northerly winds. Fewer locations
are reporting drizzle this last hour, so I expect this trend
should continue into the afternoon as the ceilings increase.
Britt
&&
.SHORT TERM: (Through Late This Afternoon)
Issued at 340 AM CDT Thu Sep 11 2014
A strong surface cold front has moved completely southeast of our
region early this morning with an extensive area of low clouds in
its wake. The radar mosaic showed the northern edge of the rain was
barely edging our region into southern Reynolds and Madison counties
in MO. The center of the airmass responsible for this cold front
was still well to the northwest of us over southern Alberta province
meaning this airmass will take considerable time to build into our
area and remain around for awhile. Temps have dipped into the 50s
for many areas north of Interstate 70, but remain in the 60s and
even lower 70s elsewhere.
A strong storm system at the upper levels will dig in across Montana
and Wyoming today and actually back the flow across our region to a
bit more southwesterly than what it is currently. This should cause
the surface front to become quasi-stationary, but still remain well
to our south. However, the better moisture in tow behind the front
will likely remain across much of southeastern MO and far southern
IL thru today. Models loosely depict a wave riding along the
stalling frontal boundary later today--more specifically late this
morning and early this afternoon--which looks to be a sufficiently
northern enough track to justify some mentionable PoP throughout a
good portion of the day in the far southern CWA in southeastern MO.
Otherwise, the atmosphere drys out enough to go with a dry forecast.
Based on PIREPs from last evening, the thickness of the cloud layer
currently over us is about 2500ft. We are less than two weeks from
the autumnal equinox and with a rather persistently decent CAA at
the low levels expected, expect this low cloud to be a bit of a
foretaste to the more stubborn cloud cover we will encounter more
frequently during the colder months. Favored a more pessimistic
cloud cover forecast a la the RAP which doesn`t really start to
break things up until later this afternoon and even then may re-gel
together tonight.
Cloudy skies for much of the day will keep temps down and this looks
like it is well handled with the 00z MOS, with maxes in the 60s.
TES
.LONG TERM: (Tonight through Wednesday)
Issued at 340 AM CDT Thu Sep 11 2014
The shortwave now diving into Montana will move into the northeast
Plains and Upper Midwest Friday. Latest guidance is in good
agreement with the speed and track of the wave as it passes north of
the area. Most of the synoptic scale lift ahead of the shortwave
will pass north of the CWFA, but we will be in the right rear
quadrant of the upper level jet and both the GFS and NAM are also
showing bands of frontogenetical forcing moving through Friday
afternoon and Friday night. Corresponding light QPF is being
produced by the models, so feel pretty confident there will be some
light rain. However am not sure how much of this precip will be
measurable so am sticking with slight chance to mid chance PoPs
Friday afternoon through Friday night as this wave moves through.
Zonal flow aloft with a 1030mb Canadian high pressure will control
the weather for the weekend. Expect this to provide the Bi-State
region with spectacular weather for those who enjoy Autumn, with
highs mainly in the mid 60s to low 70s and lows in the 40s.
Medium range guidance is indicating a pattern shift in the
atmosphere over us toward mid-week from quasi-zonal to northwest
flow aloft. The initial wave which will dig into the eastern CONUS
is forecast to pass over the Midwest Monday into Monday night. Much
like Friday`s wave, the broad synoptic lift associated with the wave
should pass north of us with a band of low level frontogenetical
forcing ahead of another cold front. Feel low chance PoPs continue
to be indicated for Monday and Monday night as this forcing affects
the region, and higher PoPs may be needed if the shortwave turns out
to be stronger than currently forecast. Another shot of Canadian
air will shift across the Midwest Tuesday into the Ohio Valley
Wednesday. Stuck close to guidance for temperatures with highs in
the 70s and lows in the 50s which continue to be below
climatology...although it may not be cool enough given the falling
heights and easterly flow as the high moves east of the area.
Carney
&&
.AVIATION: (For the 18z TAFs through 18z Friday Afternoon)
Issued at 1226 PM CDT Thu Sep 11 2014
Expect mainly MVFR conditions to persist through the rest of the
TAF period. Current ceilings are expected to improve to above 2000
feet this afternoon, though the are expected to remain below 3000
feet through the night. Ceilings are expected to fall below 2000
feet with some IFR conditions possible between 08-16Z as drizzle
redevelops at the terminals. Conditions will then improve again by
mid morning Friday. Winds will be north to northeast and and
remain under 10kts.
Specifics for KSTL: Expect MVFR ceilings to persist through the
period, with bases increasing above 2000ft this afternoon.
Ceilings will fall back below 2000ft between 09-15Z with -dz
redeveloping at the terminal. Improvement is then expected after
mid morning Friday.
Britt
&&
.LSX WATCHES/WARNINGS/ADVISORIES:
MO...NONE.
IL...NONE.
&&
$$
WFO LSX
AREA FORECAST DISCUSSION...UPDATED
NWS ST LOUIS MO
1059 AM CDT Thu Sep 11 2014
.UPDATE:
Issued at 1059 AM CDT Thu Sep 11 2014
Mainly cloudy skies are expected the rest of the afternoon. The
latest RAP soundings are showing moisture being trapped below a
inversion at 900mb. This will keep temperatures from climbing much
this afternoon given the clouds and northerly winds. Fewer locations
are reporting drizzle this last hour, so I expect this trend
should continue into the afternoon as the ceilings increase.
Britt
&&
.SHORT TERM: (Through Late This Afternoon)
Issued at 340 AM CDT Thu Sep 11 2014
A strong surface cold front has moved completely southeast of our
region early this morning with an extensive area of low clouds in
its wake. The radar mosaic showed the northern edge of the rain was
barely edging our region into southern Reynolds and Madison counties
in MO. The center of the airmass responsible for this cold front
was still well to the northwest of us over southern Alberta province
meaning this airmass will take considerable time to build into our
area and remain around for awhile. Temps have dipped into the 50s
for many areas north of Interstate 70, but remain in the 60s and
even lower 70s elsewhere.
A strong storm system at the upper levels will dig in across Montana
and Wyoming today and actually back the flow across our region to a
bit more southwesterly than what it is currently. This should cause
the surface front to become quasi-stationary, but still remain well
to our south. However, the better moisture in tow behind the front
will likely remain across much of southeastern MO and far southern
IL thru today. Models loosely depict a wave riding along the
stalling frontal boundary later today--more specifically late this
morning and early this afternoon--which looks to be a sufficiently
northern enough track to justify some mentionable PoP throughout a
good portion of the day in the far southern CWA in southeastern MO.
Otherwise, the atmosphere drys out enough to go with a dry forecast.
Based on PIREPs from last evening, the thickness of the cloud layer
currently over us is about 2500ft. We are less than two weeks from
the autumnal equinox and with a rather persistently decent CAA at
the low levels expected, expect this low cloud to be a bit of a
foretaste to the more stubborn cloud cover we will encounter more
frequently during the colder months. Favored a more pessimistic
cloud cover forecast a la the RAP which doesn`t really start to
break things up until later this afternoon and even then may re-gel
together tonight.
Cloudy skies for much of the day will keep temps down and this looks
like it is well handled with the 00z MOS, with maxes in the 60s.
TES
.LONG TERM: (Tonight through Wednesday)
Issued at 340 AM CDT Thu Sep 11 2014
The shortwave now diving into Montana will move into the northeast
Plains and Upper Midwest Friday. Latest guidance is in good
agreement with the speed and track of the wave as it passes north of
the area. Most of the synoptic scale lift ahead of the shortwave
will pass north of the CWFA, but we will be in the right rear
quadrant of the upper level jet and both the GFS and NAM are also
showing bands of frontogenetical forcing moving through Friday
afternoon and Friday night. Corresponding light QPF is being
produced by the models, so feel pretty confident there will be some
light rain. However am not sure how much of this precip will be
measurable so am sticking with slight chance to mid chance PoPs
Friday afternoon through Friday night as this wave moves through.
Zonal flow aloft with a 1030mb Canadian high pressure will control
the weather for the weekend. Expect this to provide the Bi-State
region with spectacular weather for those who enjoy Autumn, with
highs mainly in the mid 60s to low 70s and lows in the 40s.
Medium range guidance is indicating a pattern shift in the
atmosphere over us toward mid-week from quasi-zonal to northwest
flow aloft. The initial wave which will dig into the eastern CONUS
is forecast to pass over the Midwest Monday into Monday night. Much
like Friday`s wave, the broad synoptic lift associated with the wave
should pass north of us with a band of low level frontogenetical
forcing ahead of another cold front. Feel low chance PoPs continue
to be indicated for Monday and Monday night as this forcing affects
the region, and higher PoPs may be needed if the shortwave turns out
to be stronger than currently forecast. Another shot of Canadian
air will shift across the Midwest Tuesday into the Ohio Valley
Wednesday. Stuck close to guidance for temperatures with highs in
the 70s and lows in the 50s which continue to be below
climatology...although it may not be cool enough given the falling
heights and easterly flow as the high moves east of the area.
Carney
&&
.AVIATION: (For the 12z TAFs through 12z Friday Morning)
Issued at 652 AM CDT Thu Sep 11 2014
MVFR ceilings are expected to prevail at the TAF sites thru much,
if not all, of the valid period. For early this morning, also
expect brief periods of drizzle mixed in with some lower ceilings,
perhaps to IFR levels. Otherwise, northerly surface winds between
5 and 10 knots will continue.
Specifics for KSTL: MVFR ceilings thru the period. Brief periods
of drizzle and IFR ceilings also expected with this becoming less
likely heading into late morning. Otherwise, northerly winds
around 10 knots.
TES
&&
.LSX WATCHES/WARNINGS/ADVISORIES:
MO...NONE.
IL...NONE.
&&
$$
WFO LSX
AREA FORECAST DISCUSSION...UPDATED AVIATION
NWS ST LOUIS MO
652 AM CDT Thu Sep 11 2014
.SHORT TERM: (Through Late This Afternoon)
Issued at 340 AM CDT Thu Sep 11 2014
A strong surface cold front has moved completely southeast of our
region early this morning with an extensive area of low clouds in
its wake. The radar mosaic showed the northern edge of the rain was
barely edging our region into southern Reynolds and Madison counties
in MO. The center of the airmass responsible for this cold front
was still well to the northwest of us over southern Alberta province
meaning this airmass will take considerable time to build into our
area and remain around for awhile. Temps have dipped into the 50s
for many areas north of Interstate 70, but remain in the 60s and
even lower 70s elsewhere.
A strong storm system at the upper levels will dig in across Montana
and Wyoming today and actually back the flow across our region to a
bit more southwesterly than what it is currently. This should cause
the surface front to become quasi-stationary, but still remain well
to our south. However, the better moisture in tow behind the front
will likely remain across much of southeastern MO and far southern
IL thru today. Models loosely depict a wave riding along the
stalling frontal boundary later today--more specifically late this
morning and early this afternoon--which looks to be a sufficiently
northern enough track to justify some mentionable PoP throughout a
good portion of the day in the far southern CWA in southeastern MO.
Otherwise, the atmosphere drys out enough to go with a dry forecast.
Based on PIREPs from last evening, the thickness of the cloud layer
currently over us is about 2500ft. We are less than two weeks from
the autumnal equinox and with a rather persistently decent CAA at
the low levels expected, expect this low cloud to be a bit of a
foretaste to the more stubborn cloud cover we will encounter more
frequently during the colder months. Favored a more pessimistic
cloud cover forecast a la the RAP which doesn`t really start to
break things up until later this afternoon and even then may re-gel
together tonight.
Cloudy skies for much of the day will keep temps down and this looks
like it is well handled with the 00z MOS, with maxes in the 60s.
TES
.LONG TERM: (Tonight through Wednesday)
Issued at 340 AM CDT Thu Sep 11 2014
The shortwave now diving into Montana will move into the northeast
Plains and Upper Midwest Friday. Latest guidance is in good
agreement with the speed and track of the wave as it passes north of
the area. Most of the synoptic scale lift ahead of the shortwave
will pass north of the CWFA, but we will be in the right rear
quadrant of the upper level jet and both the GFS and NAM are also
showing bands of frontogenetical forcing moving through Friday
afternoon and Friday night. Corresponding light QPF is being
produced by the models, so feel pretty confident there will be some
light rain. However am not sure how much of this precip will be
measurable so am sticking with slight chance to mid chance PoPs
Friday afternoon through Friday night as this wave moves through.
Zonal flow aloft with a 1030mb Canadian high pressure will control
the weather for the weekend. Expect this to provide the Bi-State
region with spectacular weather for those who enjoy Autumn, with
highs mainly in the mid 60s to low 70s and lows in the 40s.
Medium range guidance is indicating a pattern shift in the
atmosphere over us toward mid-week from quasi-zonal to northwest
flow aloft. The initial wave which will dig into the eastern CONUS
is forecast to pass over the Midwest Monday into Monday night. Much
like Friday`s wave, the broad synoptic lift associated with the wave
should pass north of us with a band of low level frontogenetical
forcing ahead of another cold front. Feel low chance PoPs continue
to be indicated for Monday and Monday night as this forcing affects
the region, and higher PoPs may be needed if the shortwave turns out
to be stronger than currently forecast. Another shot of Canadian
air will shift across the Midwest Tuesday into the Ohio Valley
Wednesday. Stuck close to guidance for temperatures with highs in
the 70s and lows in the 50s which continue to be below
climatology...although it may not be cool enough given the falling
heights and easterly flow as the high moves east of the area.
Carney
&&
.AVIATION: (For the 12z TAFs through 12z Friday Morning)
Issued at 652 AM CDT Thu Sep 11 2014
MVFR ceilings are expected to prevail at the TAF sites thru much,
if not all, of the valid period. For early this morning, also
expect brief periods of drizzle mixed in with some lower ceilings,
perhaps to IFR levels. Otherwise, northerly surface winds between
5 and 10 knots will continue.
Specifics for KSTL: MVFR ceilings thru the period. Brief periods
of drizzle and IFR ceilings also expected with this becoming less
likely heading into late morning. Otherwise, northerly winds
around 10 knots.
TES
&&
.LSX WATCHES/WARNINGS/ADVISORIES:
MO...NONE.
IL...NONE.
&&
$$
WFO LSX
AREA FORECAST DISCUSSION
NWS ST LOUIS MO
340 AM CDT Thu Sep 11 2014
.SHORT TERM: (Through Late This Afternoon)
Issued at 340 AM CDT Thu Sep 11 2014
A strong surface cold front has moved completely southeast of our
region early this morning with an extensive area of low clouds in
its wake. The radar mosaic showed the northern edge of the rain was
barely edging our region into southern Reynolds and Madison counties
in MO. The center of the airmass responsible for this cold front
was still well to the northwest of us over southern Alberta province
meaning this airmass will take considerable time to build into our
area and remain around for awhile. Temps have dipped into the 50s
for many areas north of Interstate 70, but remain in the 60s and
even lower 70s elsewhere.
A strong storm system at the upper levels will dig in across Montana
and Wyoming today and actually back the flow across our region to a
bit more southwesterly than what it is currently. This should cause
the surface front to become quasi-stationary, but still remain well
to our south. However, the better moisture in tow behind the front
will likely remain across much of southeastern MO and far southern
IL thru today. Models loosely depict a wave riding along the
stalling frontal boundary later today--more specifically late this
morning and early this afternoon--which looks to be a sufficiently
northern enough track to justify some mentionable PoP throughout a
good portion of the day in the far southern CWA in southeastern MO.
Otherwise, the atmosphere drys out enough to go with a dry forecast.
Based on PIREPs from last evening, the thickness of the cloud layer
currently over us is about 2500ft. We are less than two weeks from
the autumnal equinox and with a rather persistently decent CAA at
the low levels expected, expect this low cloud to be a bit of a
foretaste to the more stubborn cloud cover we will encounter more
frequently during the colder months. Favored a more pessimistic
cloud cover forecast a la the RAP which doesn`t really start to
break things up until later this afternoon and even then may re-gel
together tonight.
Cloudy skies for much of the day will keep temps down and this looks
like it is well handled with the 00z MOS, with maxes in the 60s.
TES
.LONG TERM: (Tonight through Wednesday)
Issued at 340 AM CDT Thu Sep 11 2014
The shortwave now diving into Montana will move into the northeast
Plains and Upper Midwest Friday. Latest guidance is in good
agreement with the speed and track of the wave as it passes north of
the area. Most of the synoptic scale lift ahead of the shortwave
will pass north of the CWFA, but we will be in the right rear
quadrant of the upper level jet and both the GFS and NAM are also
showing bands of frontogenetical forcing moving through Friday
afternoon and Friday night. Corresponding light QPF is being
produced by the models, so feel pretty confident there will be some
light rain. However am not sure how much of this precip will be
measurable so am sticking with slight chance to mid chance PoPs
Friday afternoon through Friday night as this wave moves through.
Zonal flow aloft with a 1030mb Canadian high pressure will control
the weather for the weekend. Expect this to provide the Bi-State
region with spectacular weather for those who enjoy Autumn, with
highs mainly in the mid 60s to low 70s and lows in the 40s.
Medium range guidance is indicating a pattern shift in the
atmosphere over us toward mid-week from quasi-zonal to northwest
flow aloft. The initial wave which will dig into the eastern CONUS
is forecast to pass over the Midwest Monday into Monday night. Much
like Friday`s wave, the broad synoptic lift associated with the wave
should pass north of us with a band of low level frontogenetical
forcing ahead of another cold front. Feel low chance PoPs continue
to be indicated for Monday and Monday night as this forcing affects
the region, and higher PoPs may be needed if the shortwave turns out
to be stronger than currently forecast. Another shot of Canadian
air will shift across the Midwest Tuesday into the Ohio Valley
Wednesday. Stuck close to guidance for temperatures with highs in
the 70s and lows in the 50s which continue to be below
climatology...although it may not be cool enough given the falling
heights and easterly flow as the high moves east of the area.
Carney
&&
.AVIATION: (For the 06z TAFs through 06z Thursday Night)
Issued at 1051 PM CDT Wed Sep 10 2014
Extensive area of MVFR stratus covers the Midwest in the wake of
this cold front and have a hard time seeing it dissipating
tomorrow. Northwest wind will become north-northeast by tomorrow
evening.
Specifics for KSTL:
MVFR stratus will blanket the region through tomorrow evening.
CVKING
&&
.PRELIMINARY POINT TEMPS/POPS:
Saint Louis 66 54 66 49 / 0 5 20 30
Quincy 63 49 62 43 / 0 10 30 30
Columbia 66 52 64 45 / 0 5 30 20
Jefferson City 66 53 65 47 / 0 5 30 20
Salem 68 53 67 51 / 5 5 10 30
Farmington 67 52 66 50 / 10 10 10 30
&&
.LSX WATCHES/WARNINGS/ADVISORIES:
MO...NONE.
IL...NONE.
&&
$$
WFO LSX
AREA FORECAST DISCUSSION
NWS OMAHA/VALLEY NE
929 PM CDT FRI SEP 12 2014
.UPDATE...
ISSUED AT 924 PM CDT FRI SEP 12 2014
OPTED TO EXPAND THE FROST ADVISORY FOR JUST A COUPLE OF COUNTIES
WHERE TEMPS ARE FORECAST TO DROP TO NEAR 36. MAY ALSO SEE SOME
PATCHY FOG OVERNIGHT. IT MAY BE VERY THIN GROUND FOG...AND MAYBE
MORE STEAM FOG NEAR THE RIVERS AND LAKES. MAY HAVE TO ADD TO THE
FORECAST IF IT BECOMES WIDESPREAD OR DENSE ENOUGH...AND WILL
CONTINUE TO MONITOR THROUGH THE NIGHTTIME. FOG HAD ALREADY
DEVELOPED AT CLARINDA IOWA AND MILLARD...AND LATEST RAP MODEL
SUGGESTS IT COULD EXPAND ESPECIALLY ACROSS WESTERN IOWA WHERE
WINDS WILL PROBABLY REMAIN CALM OVERNIGHT.
&&
.SHORT TERM...(TONIGHT THROUGH MONDAY)
ISSUED AT 319 PM CDT FRI SEP 12 2014
...FIRST FROST OF THE SEASON EXPECTED FOR PARTS OF THE AREA...
THE MAIN CONCERN CONCERN FOR THE SHORT TERM CONTS TO BE WITH THE
COLD WEATHER TONIGHT. WE FEEL THAT MOST LOCATIONS WILL FALL SHORT
OF THE RECORDS LOWS...BUT WITH SKIES CLEARING...WINDS DIMINISHING
THIS EVENING...AND THE SFC HIGH CROSSING THE CWA OVERNIGHT WE ARE
IN FOR THE COLDEST NIGHT YET OF THE EARLY FALL SEASON. GOING
FORECAST LOWS WERE IN GOOD SHAPE AND VERY FEW CHANGES WERE MADE
THERE...BUT WE DID GO AHEAD AND ISSUE A FROST ADVRY FOR PARTS OF
THE AREA THAT WILL LIKELY SEE A COUPLE HOURS OF TEMPERATURES AT OR
BELOW ABOUT 36 DEGREES. RETURN FLOW STARTS TO KICK ON ON SAT BUT
TEMPERATURES WILL REMAIN BELOW NORMAL DESPITE THE MIXING TO 850
MB. LOWS TEMPERATURES WILL BE A BIT WARMER ON SAT NIGHT AHEAD OF
A FRONT THAT WILL START TO WORK INTO THE MID MO RVR VALLEY ON SUN.
ALL MODELS ARE IN PRETTY GOOD AGREEMENT ON THE EVOLUTION OF THE
SENSIBLE WX ASSOCIATED WITH THE FRONT ON SUN/SUN NIGHT ALLOWING
FOR INCREASED CONFIDENCE AND HIGHER POPS. MOISTURE RETURN WILL BE
LIMITED BUT ISENTROPIC LIFT WILL INCREASE DURING THE DAY ON SUN
LEADING TO INCREASING CLOUDS...AND AS LARGE-SCALE FORCING FOR
ASCENT ALSO INCREASES LATE ON SUN AFTN...AS A SHORT-WAVE TROUGH
WORKS THRU SD...WE SHOULD SEE AN INCREASE IN SHRA AND MAYBE AN
ISO TSRA OR TWO. THIS CHANCE WILL CONT TO INCREASE ON SUN NIGHT
AND WE WILL HAVE SOME LIKELY POPS IN THE CNTRL AND SRN CWA. THE
FRONT WILL SHIFT SOUTH OF OUR AREA ON MON ALLOW FOR ANOTHER SHOT
OF COOLER AIR TO MOV IN FOR MON AND MON NIGHT AND WE HAVE LOWERED
HIGHS/LOWS DURING THIS TIME.
.LONG TERM...(MONDAY NIGHT THROUGH FRIDAY)
ISSUED AT 319 PM CDT FRI SEP 12 2014
SENSIBLE WEATHER WILL BE PRETTY QUIET IN THE EXTENDED PERIOD OF
THE FORECAST. THE OVER-ALL PATTERN WILL TRANSITION FROM NORTHWEST
FLOW AND COOL AT THE START OF THE PERIOD TO WESTERLY AND A BIT
WARMER AT THE END. THE PERIOD WILL GENERALLY BE DRY BUT AS THE
UPPER LEVEL FLOW TURNS MORE WEST WE WILL SEE AN INCREASE IN
MOISTURE THAT MAY LEAD TO SOME CHC FOR PRECIP TOWARDS THE END OF
THE PERIOD...ESPECIALLY IN THE NORTHERN CWA CLOSER TO A BOUNDARY.
&&
.AVIATION...(00Z TAFS FOR KOFK...KLNK AND KOMA.)
ISSUED AT 524 PM CDT FRI SEP 12 2014
VFR CONDITIONS INITIALLY WITH CLOUDS DISSIPATING BY 01-03Z WITH
WINDS BECOMING LIGHT AND VARIABLE. COULD BE SOME MVFR FOG AT ALL
THREE TAF SITES 10-13Z. COULD BE PATCHY FROST AT KLNK/KOFK LATE
TONIGHT AS WELL. WINDS BECOME SOUTH TOMORROW MORNING AND INCREASE
TO 13 TO 15 KNOTS BY 15-16Z...AND COULD SEE GUSTS AT KOFK UP TO 22
KNOTS THROUGH THE AFTERNOON. MAY ALSO SEE FEW-SCT CUMULUS CLOUDS
DEVELOP SATURDAY.
&&
.OAX WATCHES/WARNINGS/ADVISORIES...
NE...FROST ADVISORY FROM 3 AM TO 9 AM CDT SATURDAY FOR NEZ015>018-
030>034-042>045-050-051-065-066-078-088-089.
IA...FROST ADVISORY FROM 3 AM TO 9 AM CDT SATURDAY FOR IAZ043-055-056-
069-079-080-090-091.
&&
$$
UPDATE...DEWALD
SHORT TERM...BOUSTEAD
LONG TERM...BOUSTEAD
AVIATION...DEWALD
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
1041 PM EDT FRI SEP 12 2014
.SYNOPSIS...
A COLD FRONT WILL BRING UNSETTLED WEATHER THROUGH THE WEEKEND. THE
FRONT WILL WEAKEN ON MONDAY BUT MOISTURE WILL LINGER FOR A
SCATTERING OF SHOWERS ON MONDAY. ANOTHER COLD FRONT SHOULD AFFECT
THE REGION ON WEDNESDAY.
&&
.NEAR TERM /UNTIL 6 AM SATURDAY MORNING/...
AS OF 10:30 PM FRIDAY...ALTHOUGH MOST OF THE FORECAST AREA THIS
EVENING SAW STRATIFORM RAIN OF GRADUALLY DIMINISHING EXTENT...THE
CAPE FEAR REGION AND WILMINGTON IN PARTICULAR EXPERIENCED A HEAVY
RAIN EVENT COMPLETE WITH LOCALIZED FLOODING. IT APPEARS THAT A
SERIES OF UNFORTUNATELY PLACED BOUNDARY COLLISIONS AND A JUICY
AIR-MASS WERE RESPONSIBLE. LIGHT TO MODERATE RAIN IS STILL
BLANKETING NEW HANOVER COUNTY AND A FLOOD WARNING IS OUT FOR THAT
AREA. GIVEN P/W VALUES IN EXCESS OF 2 INCHES SHOWER ACTIVITY AREA-
WIDE CONTINUES TO BE A POSSIBILITY...ESPECIALLY GIVEN THE
PROXIMITY OF THE COLD FRONT...WHICH SEEMS TO NOW EXTEND ACROSS THE
NORTHERN HALF OF THE FORECAST AREA WITH A FRONTAL WAVE NOW PLACED
OVER THE CAPE FEAR REGION. THIS ALSO NO DOUBT ENHANCED OUR RECENT
BOUT OF HEAVY RAIN.
&&
.SHORT TERM /6 AM SATURDAY MORNING THROUGH SUNDAY NIGHT/...
AS OF 3 PM FRIDAY...ANOTHER FAIRLY UNSETTLED AFTERNOON IN STORE FOR
THE REGION SATURDAY AS COLD FRONT ENTERS THE COASTAL PLAIN IN THE
PRESENCE OF FAIRLY DEEP TROPICAL MOISTURE. THE MOST WIDESPREAD
COVERAGE WILL BE OVER NWRN ZONES WHICH WILL BE MOST PROXIMAL TO THE
BOUNDARY...PERHAPS RADAR COVERAGE NOT UNLIKE THAT OF THIS AFTERNOON.
WITH A MORE CLOUDY START COMPARED TO TODAY AFTERNOON TEMPERATURES
WILL NOT GROW AS HOT AND TEND TO BE QUITE SEASONABLE. PRECIPITABLE
WATER REMAINS ABOVE 2 INCHES WHILE STORM MOTION REMAINS BELOW 5KT SO
CHANCE FOR HEAVY DOWNPOURS REMAINS INTACT. RAIN CHANCES WILL HAVE A
HARD TIME DIPPING MUCH LOWER THAN LOW END CHANCE RANGE SATURDAY
NIGHT AS THE FRONT MOVES ATOP OF THE FORECAST AREA...ALTHOUGH THE
LOSS OF DAYTIME HEATING SHOULD DIMINISH THEIR INTENSITY AND THE
HEAVY RAIN THREAT. WE WIND UP ON THE OTHER SIDE OF THE FRONT ON
SUNDAY AS IT REMAINS NEARLY STALLED TO OUR SOUTH AND EAST. RAIN
CHANCES WILL BE SHIFTED SOUTH AND EAST ACCORDINGLY AND THE HEAVY
RAIN THREAT WILL BE RELATIVELY MITIGATED. SUNDAY AFTERNOON MAY OFFER
UP A RANGE OF HIGH TEMPERATURES FROM NORTH TO SOUTH FROM THE UPPER
70S TO THE MID 80S.
&&
.LONG TERM /MONDAY THROUGH FRIDAY/...
AS OF 3 PM FRIDAY...WEAKENING FRONT STALLED IN THE AREA AT THE START
OF THE PERIOD AND DEEP TROPICAL MOISTURE ENSURE THE FIRST HALF OF
NEXT WEEK REMAIN UNSETTLED. PRECIPITABLE WATER VALUES AROUND 2
INCHES MON AND TUE IN A MODERATELY UNSTABLE AIRMASS SHOULD LEAD TO
SHOWER AND THUNDERSTORM DEVELOPMENT. PLAN TO CARRY CHC POP WITH A
DIURNAL DISTRIBUTION. THE LACK OF FORCING ALOFT SHOULD LEAD TO A
DECREASE IN COVERAGE/ACTIVITY OVERNIGHT BUT DO NOT THINK STORMS WILL
COMPLETELY DISSIPATE. STORM MOTIONS WILL REMAIN 10 KT OR LESS WHICH
WILL MAINTAIN FLOODING POTENTIAL.
A STRONGER COLD FRONT WILL DROP IN FROM THE NORTHWEST MID WEEK. THIS
FRONT HAS A MORE DEFINED TROUGH BEHIND IT WHICH WILL PUSH THE
BOUNDARY SOUTH OF THE AREA BY THE END OF THE WEEK. HOWEVER THERE IS
STILL SOME UNCERTAINTY AS TO HOW FAR SOUTH THIS FRONT MOVES BEFORE
STALLING. ECMWF HAS THE FRONT FARTHER SOUTH...SO DOES WPC...WHILE
THE GFS KEEPS THE FRONT CLOSER TO THE CAROLINAS. BOTH MEDIUM RANGE
SOLUTIONS DEVELOP A WEAK LOW ON THE FRONT AND LIFT IT NORTH...THOUGH
TIMING IS DIFFERENT. ECMWF SOLUTION WOULD PRODUCE SLIGHT CHC TO LOW
CHC OF PRECIP THROUGH THU...MAINLY ALONG THE COAST...WITH DRYING
FRI. GFS IS WETTER WITH HIGH CHC TO LIKELY POP THROUGH THE END OF
THE PERIOD FOR MUCH OF THE FORECAST AREA. PREVIOUS FORECASTS HAVE
BEEN IN LINE WITH THE DRIER ECMWF/WPC SOLUTION AND AT THIS POINT CAN
SEE NO REASON TO MAKE A CHANGE. CONFIDENCE REMAINS LOW SO
SIGNIFICANT CHANGES IN LATER FORECASTS IS STILL A POSSIBILITY.
TEMPERATURE RANGES EARLY IN THE PERIOD WILL BE ON THE NARROW END
WITH CLOUD COVER AND PRECIP KEEPING HIGHS NEAR TO SLIGHTLY BELOW
CLIMO BUT HELPING HOLD LOWS SEVERAL DEGREES ABOVE CLIMO. PASSAGE OF
FRONT MID WEEK WILL BRING BELOW CLIMO TEMPS FOR THE END OF THE WEEK.
&&
.AVIATION /03Z SATURDAY THROUGH WEDNESDAY/...
AS OF 00Z...EXPECT SHRA/TSRA TO END EARLY THIS EVENING...WITH
WIDESPREAD STRATIFORM LIGHT RAIN DECREASING THEN ENDING AROUND
MIDNIGHT. THE HRRR MODELS SUGGESTS SOME ISOLATED CONVECTIVE SHOWERS
MAY REDEVELOP AROUND MIDNIGHT NEAR KILM AND 10Z NEAR KLBT.
UNTIL CONVECTION DISSIPATES THIS EVENING THERE WILL BE A CHANCE OF
TEMPO MVFR CONDITIONS. BRIEF IFR POSSIBLE IF A SHOWER MOVES
DIRECTLY OVER A TERMINAL...BUT CONFIDENCE IS LOW. GENERALLY EXPECT
THICK MID/UPPER CLOUD COVER THROUGH THE TAF VALID PERIOD WITH
COPIOUS AMOUNTS OF LOW LEVEL MOISTURE. IFR/LIFR CONDITIONS WILL
DEVELOP AFTER 08Z AT KLBT/KILM/FLO WITH HIGHEST CONFIDENCE AT
KLBT/KILM WHICH IS NEAREST THE STATIONARY FRONT. KCRE/KMYR ARE MORE
LIKELY TO EXPERIENCE MVFR CONDITIONS OVERNIGHT. IFR LIFTS FAIRLY
QUICKLY SATURDAY MORNING WITH VFR DEVELOPING AT ALL TERMINALS BY
18Z. CLOUD COVER SHOULD INHIBIT HEATING AND LIFT SO THINK WORSE CASE
VCSH COASTAL TERMINALS IN THE MORNING HOURS. BY AFTERNOON
THUNDERSTORM POTENTIAL SHOULD BE GREATEST AT KFLO/KLBT.
EXTENDED OUTLOOK...A CHANCE OF SHOWERS WITH MAINLY AFTERNOON
THUNDERSTORMS/TEMPO MVFR THROUGH TUESDAY.
&&
.MARINE...
NEAR TERM/THROUGH TONIGHT/...
AS OF 10:30 PM FRIDAY...LIGHT AND VARIABLE WINDS WITH 2 FT SEAS
CONTINUE ACROSS THE WATERS THIS EVENING. FORECAST REMAINS
UNCHANGED. PREVIOUS DISCUSSION FOLLOWS:
OUTSIDE OF TSTMS NO REAL PROBLEMS EXPECTED ON THE WATERS WITH
LIGHT WINDS OVERALL AND SEAS 2 FEET OR LESS...AS A WEAK FRONTAL
BOUNDARY REMAINS IN VICINITY OF THE AREA. MOST STORMS SHOULD STAY
OVER LAND BUT TONIGHT CELLS MAY BEGIN TO FAVOR THE 0-20 NM WATERS.
SEAS AROUND 2 FEET IN A MIX OF SE WAVES 1-1.5 FT EVERY 8-9 SECONDS
AND S WAVES 0.5-1 FT EVERY 3-4 SECONDS. WITHIN TSTMS WINDS AND
SEAS WILL BE LOCALLY AND SIGNIFICANTLY HIGHER.
SHORT TERM /SATURDAY THROUGH SUNDAY NIGHT/...
AS OF 3 PM FRIDAY...PREFRONTAL SOUTHWESTERLY FLOW ON SATURDAY SHOULD
REMAIN AT 10 KT PREVENTING SEAS FROM ATTAINING HEIGHTS MORE THAN 2
FT. LATE SATURDAY NIGHT AS THE FRONT DRAWS NEAR THE COAST THERE MAY
BE A GENTLE BACKING OF THE FLOW FOLLOWED BY A MORE PRECIPITOUS VEER
ON SUNDAY ASSOCIATED WITH ACTUAL FROPA. THE FRONT WILL NOT MOVE VERY
FAR TO OUR SOUTH BEFORE STALLING WHICH PRECLUDES MUCH OF A SURGE OF
HIGH PRESSURE AND THUS ANY HIGHER WINDS. THUS THE VEER TO ENE FLOW
APPEARS TO BE THE MAIN EFFECT OF THE FROPA AS WIND SPEEDS AND WAVE
HEIGHTS REMAIN UNCHANGED...ALTHOUGH WAVE PERIODS MAY SHORTEN UP A
BIT.
LONG TERM /MONDAY THROUGH WEDNESDAY/...
AS OF 3 PM FRIDAY...DIMINISHING NORTHERLY SURGE AT THE START OF THE
PERIOD WILL LEAVE LIGHT AND VARIABLE WINDS OVER THE WATERS FOR MUCH
OF MON AND TUE GIVEN PROXIMITY TO THE STALLED FRONT. ANOTHER COLD
FRONT WILL DROP IN FROM THE NORTHWEST DURING THE SECOND HALF OF THE
PERIOD. THIS FRONT IS MORE DEFINED AND SHOULD BE ACCOMPANIED BY A
STRONGER NORTHERLY SURGE LATER WED INTO WED NIGHT. WINDS WILL
APPROACH A SOLID 15 KT WED NIGHT WITH GUSTS AROUND 20 KT POSSIBLE.
SEAS 2 TO 3 FT FOR MUCH OF THE PERIOD WILL BUILD AS HIGH AS 5 FT AS
THE PERIOD ENDS DUE TO THE PROLONGED AND STEADILY INCREASING NATURE
OF THE NORTHERLY SURGE.
&&
.ILM WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
NC...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...MBB
NEAR TERM...MJC/REK
SHORT TERM...MBB
LONG TERM...III
AVIATION...MRR
MARINE...MJC/REK/III/MBB
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
735 PM EDT FRI SEP 12 2014
.SYNOPSIS...
A COLD FRONT WILL BRING UNSETTLED WEATHER THROUGH THE WEEKEND. THE
FRONT WILL WEAKEN ON MONDAY BUT MOISTURE WILL LINGER FOR A
SCATTERING OF SHOWERS ON MONDAY. ANOTHER COLD FRONT SHOULD AFFECT
THE REGION ON WEDNESDAY.
&&
.NEAR TERM /UNTIL 6 AM SATURDAY MORNING/...
AS OF 7:30 PM FRIDAY...CONVECTION FROM THIS AFTERNOON HAS
TRANSITIONED TO A WIDESPREAD LIGHT STRATIFORM RAIN EVENT THIS
EVENING. THERE ARE A FEW EMBEDDED SHORT-LIVED THUNDERSTORMS...BUT
THEY ARE ALSO ON THE WANE. INSTABILITY PRETTY MUCH TAPPED OUT AND
CONVECTIVE ACTIVITY WAS ALMOST ENTIRELY DIURNALLY-DRIVEN...SO
EXPECT A GRADUAL DECREASE IN AREAL COVERAGE OF LIGHT RAIN THROUGH
MIDNIGHT...WITH SPOTTY SHOWERS THEREAFTER. HAVE UPDATED FORECAST
ACCORDINGLY. RELEVANT PORTION OF PREVIOUS DISCUSSION FOLLOWS:
A FEW IMPULSES ALOFT TRAVERSING THE SFC BOUNDARY WILL LIKELY KEEP
A CHANCE OF SHRA/TSTMS GOING INTO THE OVERNIGHT...BUT OVERALL
RAIN-RATES AND STORM COVERAGE IS EXPECTED TO SHOW SOME SCALING
BACK AS SURFACE HEATING TAILS OFF AND IS TAPPED INTO OVER THE NEXT
8 HOURS.
&&
.SHORT TERM /6 AM SATURDAY MORNING THROUGH SUNDAY NIGHT/...
AS OF 3 PM FRIDAY...ANOTHER FAIRLY UNSETTLED AFTERNOON IN STORE FOR
THE REGION SATURDAY AS COLD FRONT ENTERS THE COASTAL PLAIN IN THE
PRESENCE OF FAIRLY DEEP TROPICAL MOISTURE. THE MOST WIDESPREAD
COVERAGE WILL BE OVER NWRN ZONES WHICH WILL BE MOST PROXIMAL TO THE
BOUNDARY...PERHAPS RADAR COVERAGE NOT UNLIKE THAT OF THIS AFTERNOON.
WITH A MORE CLOUDY START COMPARED TO TODAY AFTERNOON TEMPERATURES
WILL NOT GROW AS HOT AND TEND TO BE QUITE SEASONABLE. PRECIPITABLE
WATER REMAINS ABOVE 2 INCHES WHILE STORM MOTION REMAINS BELOW 5KT SO
CHANCE FOR HEAVY DOWNPOURS REMAINS INTACT. RAIN CHANCES WILL HAVE A
HARD TIME DIPPING MUCH LOWER THAN LOW END CHANCE RANGE SATURDAY
NIGHT AS THE FRONT MOVES ATOP OF THE FORECAST AREA...ALTHOUGH THE
LOSS OF DAYTIME HEATING SHOULD DIMINISH THEIR INTENSITY AND THE
HEAVY RAIN THREAT. WE WIND UP ON THE OTHER SIDE OF THE FRONT ON
SUNDAY AS IT REMAINS NEARLY STALLED TO OUR SOUTH AND EAST. RAIN
CHANCES WILL BE SHIFTED SOUTH AND EAST ACCORDINGLY AND THE HEAVY
RAIN THREAT WILL BE RELATIVELY MITIGATED. SUNDAY AFTERNOON MAY OFFER
UP A RANGE OF HIGH TEMPERATURES FROM NORTH TO SOUTH FROM THE UPPER
70S TO THE MID 80S.
&&
.LONG TERM /MONDAY THROUGH FRIDAY/...
AS OF 3 PM FRIDAY...WEAKENING FRONT STALLED IN THE AREA AT THE START
OF THE PERIOD AND DEEP TROPICAL MOISTURE ENSURE THE FIRST HALF OF
NEXT WEEK REMAIN UNSETTLED. PRECIPITABLE WATER VALUES AROUND 2
INCHES MON AND TUE IN A MODERATELY UNSTABLE AIRMASS SHOULD LEAD TO
SHOWER AND THUNDERSTORM DEVELOPMENT. PLAN TO CARRY CHC POP WITH A
DIURNAL DISTRIBUTION. THE LACK OF FORCING ALOFT SHOULD LEAD TO A
DECREASE IN COVERAGE/ACTIVITY OVERNIGHT BUT DO NOT THINK STORMS WILL
COMPLETELY DISSIPATE. STORM MOTIONS WILL REMAIN 10 KT OR LESS WHICH
WILL MAINTAIN FLOODING POTENTIAL.
A STRONGER COLD FRONT WILL DROP IN FROM THE NORTHWEST MID WEEK. THIS
FRONT HAS A MORE DEFINED TROUGH BEHIND IT WHICH WILL PUSH THE
BOUNDARY SOUTH OF THE AREA BY THE END OF THE WEEK. HOWEVER THERE IS
STILL SOME UNCERTAINTY AS TO HOW FAR SOUTH THIS FRONT MOVES BEFORE
STALLING. ECMWF HAS THE FRONT FARTHER SOUTH...SO DOES WPC...WHILE
THE GFS KEEPS THE FRONT CLOSER TO THE CAROLINAS. BOTH MEDIUM RANGE
SOLUTIONS DEVELOP A WEAK LOW ON THE FRONT AND LIFT IT NORTH...THOUGH
TIMING IS DIFFERENT. ECMWF SOLUTION WOULD PRODUCE SLIGHT CHC TO LOW
CHC OF PRECIP THROUGH THU...MAINLY ALONG THE COAST...WITH DRYING
FRI. GFS IS WETTER WITH HIGH CHC TO LIKELY POP THROUGH THE END OF
THE PERIOD FOR MUCH OF THE FORECAST AREA. PREVIOUS FORECASTS HAVE
BEEN IN LINE WITH THE DRIER ECMWF/WPC SOLUTION AND AT THIS POINT CAN
SEE NO REASON TO MAKE A CHANGE. CONFIDENCE REMAINS LOW SO
SIGNIFICANT CHANGES IN LATER FORECASTS IS STILL A POSSIBILITY.
TEMPERATURE RANGES EARLY IN THE PERIOD WILL BE ON THE NARROW END
WITH CLOUD COVER AND PRECIP KEEPING HIGHS NEAR TO SLIGHTLY BELOW
CLIMO BUT HELPING HOLD LOWS SEVERAL DEGREES ABOVE CLIMO. PASSAGE OF
FRONT MID WEEK WILL BRING BELOW CLIMO TEMPS FOR THE END OF THE WEEK.
&&
.AVIATION /23Z FRIDAY THROUGH WEDNESDAY/...
AS OF 00Z...EXPECT SHRA/TSRA TO END EARLY THIS EVENING...WITH
WIDESPREAD STRATIFORM LIGHT RAIN DECREASING THEN ENDING AROUND
MIDNIGHT. THE HRRR MODELS SUGGESTS SOME ISOLATED CONVECTIVE SHOWERS
MAY REDEVELOP AROUND MIDNIGHT NEAR KILM AND 10Z NEAR KLBT.
UNTIL CONVECTION DISSIPATES THIS EVENING THERE WILL BE A CHANCE OF
TEMPO MVFR CONDITIONS. BRIEF IFR POSSIBLE IF A SHOWER MOVES
DIRECTLY OVER A TERMINAL...BUT CONFIDENCE IS LOW. GENERALLY EXPECT
THICK MID/UPPER CLOUD COVER THROUGH THE TAF VALID PERIOD WITH
COPIOUS AMOUNTS OF LOW LEVEL MOISTURE. IFR/LIFR CONDITIONS WILL
DEVELOP AFTER 08Z AT KLBT/KILM/FLO WITH HIGHEST CONFIDENCE AT
KLBT/KILM WHICH IS NEAREST THE STATIONARY FRONT. KCRE/KMYR ARE MORE
LIKELY TO EXPERIENCE MVFR CONDITIONS OVERNIGHT. IFR LIFTS FAIRLY
QUICKLY SATURDAY MORNING WITH VFR DEVELOPING AT ALL TERMINALS BY
18Z. CLOUD COVER SHOULD INHIBIT HEATING AND LIFT SO THINK WORSE CASE
VCSH COASTAL TERMINALS IN THE MORNING HOURS. BY AFTERNOON
THUNDERSTORM POTENTIAL SHOULD BE GREATEST AT KFLO/KLBT.
EXTENDED OUTLOOK...A CHANCE OF SHOWERS WITH MAINLY AFTERNOON
THUNDERSTORMS/TEMPO MVFR THROUGH TUESDAY.
&&
.MARINE...
NEAR TERM/THROUGH TONIGHT/...
AS OF 7:30 PM FRIDAY...LIGHT AND VARIABLE WINDS WITH 2 FT SEAS
CONTINUE ACROSS THE WATERS THIS EVENING. FORECAST REMAINS
UNCHANGED. PREVIOUS DISCUSSION FOLLOWS:
OUTSIDE OF TSTMS NO REAL PROBLEMS EXPECTED ON THE WATERS WITH
LIGHT WINDS OVERALL AND SEAS 2 FEET OR LESS...AS A WEAK FRONTAL
BOUNDARY REMAINS IN VICINITY OF THE AREA. MOST STORMS SHOULD STAY
OVER LAND BUT TONIGHT CELLS MAY BEGIN TO FAVOR THE 0-20 NM WATERS.
SEAS AROUND 2 FEET IN A MIX OF SE WAVES 1-1.5 FT EVERY 8-9 SECONDS
AND S WAVES 0.5-1 FT EVERY 3-4 SECONDS. WITHIN TSTMS WINDS AND
SEAS WILL BE LOCALLY AND SIGNIFICANTLY HIGHER.
SHORT TERM /SATURDAY THROUGH SUNDAY NIGHT/...
AS OF 3 PM FRIDAY...PREFRONTAL SOUTHWESTERLY FLOW ON SATURDAY SHOULD
REMAIN AT 10 KT PREVENTING SEAS FROM ATTAINING HEIGHTS MORE THAN 2
FT. LATE SATURDAY NIGHT AS THE FRONT DRAWS NEAR THE COAST THERE MAY
BE A GENTLE BACKING OF THE FLOW FOLLOWED BY A MORE PRECIPITOUS VEER
ON SUNDAY ASSOCIATED WITH ACTUAL FROPA. THE FRONT WILL NOT MOVE VERY
FAR TO OUR SOUTH BEFORE STALLING WHICH PRECLUDES MUCH OF A SURGE OF
HIGH PRESSURE AND THUS ANY HIGHER WINDS. THUS THE VEER TO ENE FLOW
APPEARS TO BE THE MAIN EFFECT OF THE FROPA AS WIND SPEEDS AND WAVE
HEIGHTS REMAIN UNCHANGED...ALTHOUGH WAVE PERIODS MAY SHORTEN UP A
BIT.
LONG TERM /MONDAY THROUGH WEDNESDAY/...
AS OF 3 PM FRIDAY...DIMINISHING NORTHERLY SURGE AT THE START OF THE
PERIOD WILL LEAVE LIGHT AND VARIABLE WINDS OVER THE WATERS FOR MUCH
OF MON AND TUE GIVEN PROXIMITY TO THE STALLED FRONT. ANOTHER COLD
FRONT WILL DROP IN FROM THE NORTHWEST DURING THE SECOND HALF OF THE
PERIOD. THIS FRONT IS MORE DEFINED AND SHOULD BE ACCOMPANIED BY A
STRONGER NORTHERLY SURGE LATER WED INTO WED NIGHT. WINDS WILL
APPROACH A SOLID 15 KT WED NIGHT WITH GUSTS AROUND 20 KT POSSIBLE.
SEAS 2 TO 3 FT FOR MUCH OF THE PERIOD WILL BUILD AS HIGH AS 5 FT AS
THE PERIOD ENDS DUE TO THE PROLONGED AND STEADILY INCREASING NATURE
OF THE NORTHERLY SURGE.
&&
.ILM WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
NC...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...MBB
NEAR TERM...MJC/REK
SHORT TERM...MBB
LONG TERM...III
AVIATION...MRR
MARINE...MJC/REK/III/MBB
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
132 PM EDT THU SEP 11 2014
.SYNOPSIS...
LATE SUMMER WEATHER CAN BE EXPECTED TODAY AHEAD OF A COLD FRONT
APPROACHING FROM THE NORTHWEST. THE FRONT WILL BRING AN INCREASING
CHANCE OF SHOWERS AND STORMS FRIDAY THROUGH MONDAY. A SERIES OF
CANADIAN HIGH PRESSURE SYSTEMS WILL BUILD INTO THE REGION A GOOD
PORTION OF NEXT WEEK...BRINGING A FEEL OF EARLY FALL TO THE AREA.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 1045 AM THURSDAY...TRIMMED MAXIMUM TEMPERATURES A DEGREE OR
2 ACROSS THE CAPE FEAR REGION DUE TO HIGH LAYERED BUT IMPACTFUL
CLOUDS PRESENTLY SAILING SOUTH OVER A SWATH OF PENDER AND NEW
HANOVER COUNTIES. OTHERWISE LITTLE CHANGE TO EXPECTED HIGHS TODAY
AND THIS IS SHAPING UP TO BE OUR WARMEST DAY IN A WHILE AND FOR A
WHILE...AS A COLD EDGES CLOSER TO THE REGION FROM THE NORTHWEST.
STRONG INSOLATION WILL CERTAINLY PROMPT CUMULUS DEVELOPMENT THIS
AFTERNOON...AND SATELLITE BASED PWAT DETECTORS ARE REGISTERING
INCREASING COLUMN MOISTURE OVER THE AREA IN THE INCREASINGLY WARM
PRE-FRONTAL AIR MASS HERE LOCALLY. THUS WITH DEWPOINT EXPECTATIONS
COUPLED WITH MAX T TODAY WILL RESULT IN MAX APPARENT TEMPERATURES
IN THE 90S MOST AREAS.
THE OTHER CHANGE WAS TO REMOVE MENTIONABLE POP VALUES FOR THE
DAYTIME PERIOD TODAY AS IT APPEARS DRY AIR WILL REMAIN IN PLACE
ABOVE 9-10KFT. WHILE A RAINDROP CANNOT BE RULED OUT COMPLETELY
ALONG THE MAXIMUM OF SEA BREEZE CONVERGENCE...AM BASING POPS ON
MEASURABLE RAINFALL PROBABILITY...AND THIS IS LESS THAN 15 PCNT
THROUGH AFTERNOON. LAND VS SEA TEMPERATURE DIFFERENTIAL SHOULD
PROPEL A HEALTHY SEA BREEZE CIRCULATION BY THE MIDDLE/LATE AFTN.
&&
.SHORT TERM /FRIDAY THROUGH SATURDAY NIGHT/...
AS OF 300 AM THURSDAY...COLD FRONT WILL MOVE ACROSS THE CAROLINAS
ON FRIDAY WITH INCREASING CLOUDS AND CHC OF SHWRS/TSTMS THROUGH
THE DAY. THE FRONT WILL SLOW DOWN AND STALL OUT IN THE VICINITY OF
LOCAL FORECAST AREA AS SHORTWAVE PUSHING THIS FRONT COMES UP
AGAINST A DECENT RIDGE IN PLACE ACROSS THE SOUTHEAST AND RIDES UP
TO THE NORTHEAST...LEAVING A FLOW MORE PARALLEL TO FRONT. THE NEXT
SHORTWAVE SHOULD NUDGE THE FRONT A LITTLE FARTHER SOUTH SAT NIGHT
BUT LOOKS LIKE IT MAY STILL REMAIN STRETCHED JUST ALONG THE
SOUTHEAST COAST. LATEST GFS RUN WAS A LITTLE FASTER...MOVING THE
FRONT INTO THE CAPE FEAR REGION BY FRI AFTERNOON. THE MAIN
SHORTWAVE ENERGY WILL REMAIN WELL NORTH OF AREA BUT CONVERGENCE
ALONG THE COLD FRONT ALONG WITH A SATURATED COLUMN WILL PRODUCE SOME
HIGHER END QPF AMOUNTS OVER FORECAST AREA. THE PCP WATER VALUES
REACH ABOVE 2.25 INCHES WITH BULLSEYE OVER LOCAL FORECAST AREA BY
FRI AFTN AND REMAINING ABOVE 2 INCHES THROUGH THE WEEKEND. OVERALL
EXPECT A CLOUDY AND WET FORECAST FOR THE WEEKEND. TEMPS OVER
SOUTHEAST NORTH CAROLINA WILL MAKE A RUN FOR 80 DEGREES ON FRIDAY
BEFORE FRONT MOVES IN WHILE TEMPS IN NORTHEAST SOUTH CAROLINA
SHOULD MAKE IT INTO THE MID 80S. CLOUDS...SHOWERS AND LIGHT
NORTHERLY FLOW WILL KEEP TEMPS BELOW NORMAL FOR HIGHS AND ABOVE
NORMAL FOR OVERNIGHT LOWS FRIDAY AND SATURDAY.
&&
.LONG TERM /SUNDAY THROUGH WEDNESDAY/...
AS OF 300 AM THURSDAY...SHORTWAVES RIDING AROUND BROAD TROUGH OVER
THE GREAT LAKES WILL PUSH PERSISTENT RIDGE OVER THE SOUTHERN CONUS
A LITTLE FARTHER SOUTH THROUGH EARLY NEXT WEEK. THE COLD FRONT
CAUGHT IN BETWEEN WILL REMAIN HUNG UP IN THE VICINITY PRODUCING
PLENTY OF CLOUDS AND UNSETTLED WEATHER THROUGH MUCH OF THE WEEK.
WILL KEEP CLOUDS AND CHC POPS IN FORECAST THROUGH AT LEAST TUES.
THE BROAD MID TO UPPER TROUGH OVER THE GREAT LAKES WILL DIG
FARTHER SOUTH THROUGH TUES AND MAY PUSH FAR ENOUGH SOUTH TO ALLOW
DRIER AIR TO MOVE IN. HIGH PRESSURE WILL BUILD DOWN INTO THE
SOUTHEAST BUT COLD FRONT WILL LINGER THROUGH THE WEEK...PERHAPS
REMAINING FAR ENOUGH SOUTH BY TUES TO ALLOW FOR SOME DRIER WEATHER
FOR MID WEEK. FOR NOW WILL KEEP CLOUDS AND PCP IN FORECAST AS
WINDS ALOFT OUT OF THE W-SW WILL RIDE OVER THE COOLER NORTHERLY
FLOW TO SUPPORT LIFT THROUGHOUT MUCH OF THE PERIOD. SHOULD END UP
WITH A DECENT QPF SPREAD OVER SEVERAL DAYS. THE COOLER NORTHERLY
FLOW ALONG WITH CLOUDS AND PCP WILL ALL COMBINE TO KEEP TEMPS
BELOW NORMAL MOST DAYS AND OVERNIGHT LOWS JUST ABOVE NORMAL.
&&
.AVIATION /18Z THURSDAY THROUGH TUESDAY/...
AS OF 18Z...FRONTAL BOUNDARY SLOW APPROACHING THROUGH THE FORECAST
PERIOD. THE HRRR DOES DEPICT SOME ISOLATED CONVECTION ALONG THE SEA
BREEZE...VERY ISOLATED AND NOT ENOUGH FOR A MENTION IN THE TAFS.
SOUTHERLY FLOW ON THE EAST SIDE OF THE RESULTANT.
TONIGHT...INCREASING CLOUDINESS TOWARD MORNING AS THE FRONT
APPROACHES. IF WE DO NOT GET A CEILING SOON ENOUGH HOWEVER...SOME
FOG MAY FORM...POSSIBLY PRETTY DENSE. WILL GO WITH THE CEILING
SCENARIO FOR NOW WITH ONLY LIGHT FOG. FRIDAY...CONVECTION BREAKING
OUT FROM WEST TO EAST. THE LATEST NAM IS NOT SO ENTHUSED WITH ONLY
ISOLATED ACTIVITY ALONG THE COAST BY AFTERNOON.
EXTENDED OUTLOOK...INCREASING CHANCES FOR SHOWERS/TSTMS AND TEMPO
MVFR FRIDAY AFTERNOON THROUGH THE WEEKEND WITH AN APPROACHING COLD
FRONT. THE FRONT STALLS WITH A CONTINUED CHANCE FOR PRECIP THROUGH
TUESDAY.
&&
.MARINE...
NEAR TERM /THROUGH TONIGHT/...
AS OF 1045 AM THURSDAY...SFC RIDGING FROM THE WESTERN ATLANTIC
HIGH...WILL PERSIST ACROSS AND AFFECT THE ILM COASTAL WATERS
THROUGH TONIGHT. THE SFC PRESSURE PATTERN WILL PRODUCE S-SW WIND
DIRECTIONS...THE SFC PRESSURE GRADIENT WILL REMAIN LOOSE INTO THIS
EVENING AND THUS PRODUCING AROUND 10 KT WIND SPEEDS. THE LOCAL SEA
BREEZE CIRCULATION WILL PROVIDE AN ADDITIONAL 5 KT THIS AFTERNOON
AND EARLY TONIGHT WITH 10-15 KT BECOMING COMMON ESPECIALLY
NEARSHORE OR WITHIN 10 NM OF THE COAST. FOR TONIGHT...THE COLD
FRONT DROPPING SE-WARD...WILL PUSH CLOSER TO THE AREA WATERS. THE
END RESULT WILL BE A SLIGHT TIGHTENING OF THE SFC PG. WILL
HIGHLIGHT WITH SW WINDS INCREASING TO 10-15 KT. SIGNIFICANT SEAS
WILL HOVER AROUND 2 FT...BUILDING TO 2 TO 3 FT THIS AFTN AND
TONIGHT DUE TO THE INCREASE OF LOW PERIOD WIND DRIVEN WAVES.
SHORT TERM /FRIDAY THROUGH SATURDAY NIGHT/...
AS OF 300 AM THURSDAY...LIGHT SOUTHERLY FLOW AHEAD OF AN
APPROACHING COLD FRONT ON FRIDAY WILL COME AROUND TO THE N-NE BY
FRI NIGHT BUT WILL REMAIN FAIRLY LIGHT IN AN OTHERWISE WEAKER
GRADIENT FLOW. OVERALL EXPECT WINDS LESS THAN 10 KTS THROUGH MUCH
OF THE WEEKEND. THIS WILL KEEP SEAS LESS THAN 3 FT FOR THE MOST
PART ACROSS THE LOCAL WATERS.
LONG TERM /SUNDAY THROUGH MONDAY/...
AS OF 300 AM THURSDAY...A SLOW MOVING COLD FRONT SHOULD GET
ANOTHER NUDGE SOUTHWARD EARLY SUNDAY HELPING IT TO PROGRESS SOUTH
THROUGH EARLY NEXT WEEK...BUT GRADIENT WILL REMAIN RELAXED KEEPING
WINDS LESS THAN 10 KTS. SEAS WILL REMAIN LESS THAN 3 FT THROUGH
THE PERIOD.
&&
.TIDES/COASTAL FLOODING...
AS OF 1045 AM THURSDAY...LATEST TIDE FORECASTS FOR THE CAPE FEAR
RIVER GAGE IN THE VICINITY OF DOWNTOWN WILMINGTON IS EXPECTED TO
APPROACH 6.00 FT MLLW AROUND NOON TODAY. THIS IS NEARLY HALF A
FOOT ABOVE THE THRESHOLD FOR COASTAL FLOODING TO OCCUR. IN
ADDITION...WATER ACROSS CANAL DRIVE OF CAROLINA BEACH IS
CORRELATED TO THE CAPE FEAR RIVER GAGE REACHING NEAR 6.00 FT MLLW.
A CFW HAS BEEN ISSUED AND IS IN EFFECT BETWEEN 11AM AND 2PM AT
WHICH TIME GAGE READINGS WILL BE AT OR ABOVE 5.5 FT MLLW.
&&
.ILM WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
NC...COASTAL FLOOD ADVISORY UNTIL 2 PM EDT THIS AFTERNOON FOR
NCZ107-108.
MARINE...NONE.
&&
$$
SYNOPSIS...MJC
NEAR TERM...MJC
SHORT TERM...RGZ
LONG TERM...RGZ
AVIATION...DL/8
TIDES...DOUGH
AREA FORECAST DISCUSSION
NWS BISMARCK ND
1146 AM CDT THU SEP 11 2014
.UPDATE...
ISSUED AT 1146 AM CDT THU SEP 11 2014
SURFACE-BASED ISOLATED SHOWER ACTIVITY HAS ALREADY DEVELOPED OVER
CENTRAL NORTH DAKOTA IN THE AREAS WHERE MID/UPPER LEVEL CLOUDS
HAVE CLEARED OUT. IT LOOKS LIKE THE LATEST HRRR IS VERIFYING THE
AREAL COVERAGE OF ISOLATED SHOWER ACTIVITY. AS A RESULT...UPDATED
THE FORECAST REFLECT THE LATEST HRRR SOLUTION AND ADDED ISOLATED
SHOWERS OVER ALL OF WESTERN AND CENTRAL NORTH DAKOTA TO THE
AFTERNOON FORECAST. THE REMAINING FORECAST ELEMENTS ARE IN GOOD
SHAPE. THE UPDATED PRODUCTS WILL BE OUT SHORTLY.
UPDATE ISSUED AT 1006 AM CDT THU SEP 11 2014
CLOUDS ARE BEGINNING TO BREAK OVER WESTERN AND CENTRAL NORTH
DAKOTA. TEMPERATURES ARE RESPONDING BY JUMPING INTO THE 40S WITHIN
THE LAST HOUR. BOWMAN RADAR SHOWS ALL RETURNS SOUTH OF THE STATE.
HOWEVER...MAINTAINED CHANCE OF LIGHT RAIN SOUTHWEST THROUGH THE
THE MORNING AS A BAROCLINIC ZONE WILL BE IN THE VICINITY.
ELSEWHERE...THE LATEST ARW AND NMM MESOSCALE MODELS PROG ISOLATED
TO SCATTERED SHOWER ACTIVITY DEVELOPING SOUTHWEST OF THE MISSOURI
RIVER THIS AFTERNOON. THE LATEST HRRR PROGS ISOLATED SHOWERS
DEVELOPING CWA-WIDE THIS AFTERNOON. GIVEN THE PROXIMITY OF THE
MOISTURE AND SUBTLE MUCAPE...WILL KEEP AFTERNOON POPS CONFINED TO
AREAS SOUTHWEST OF THE MISSOURI RIVER...SIMILAR TO THE ARW AND NMM
SOLUTIONS. AS A RESULT...CHANGED AFTERNOON WEATHER PRECIP TYPE
WORDING FROM STRATIFORM RAIN TO CONVECTIVE SHOWERS. THE UPDATED
PRODUCTS WILL BE OUT SHORTLY.
UPDATE ISSUED AT 645 AM CDT THU SEP 11 2014
LATEST SATELLITE IMAGERY SHOWS UPPER LEVEL TROUGH DROPPING SOUTH
THROUGH THE NORTHERN ROCKIES WITH STRONG JET EXTENDING FROM THE
BASE OF THE TROUGH EAST INTO THE NORTHERN PLAINS. LATEST RADAR
IMAGERY INDICATES THE MAJORITY OF THE PRECIPITATION REMAINING
SOUTH OF THE FORECAST AREA...WITH FAR SOUTHWEST BOWMAN COUNTY
SEEING SOME LIGHT RETURNS. MADE SOME MINOR ADJUSTMENTS TO
POPS...CONFINING THEM TO THE FAR SOUTHWEST EARLY THIS MORNING. IF
WE SEE SOME BREAKS IN THE CLOUDS TODAY...STRONG LOW LEVEL LAPSE
RATES SHOULD AID IN SHOWER DEVELOPMENT FARTHER NORTH AND EAST.
LATEST HRRR DEVELOPS ISOLATED CONVECTION ACROSS THE CWA BY THIS
AFTERNOON. FOR NOW WILL KEEP POPS LIMITED TO THE SOUTHWEST QUARTER
AS PREVIOUSLY FORECAST.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 346 AM CDT THU SEP 11 2014
FREEZING TEMPERATURES TONIGHT HIGHLIGHT THE SHORT TERM FORECAST.
THE 00 UTC DETERMINISTIC SUITE SUGGESTS THE CURRENT STRATUS DECK
IN PLACE THIS MORNING ACROSS WESTERN AND CENTRAL NORTH DAKOTA WILL
BEGIN TO CLEAR ACROSS THE FAR NORTH LATE THIS AFTERNOON. THE
CLEARING TREND IS FORECAST TO CONTINUE TO PUSH SOUTH THROUGH THE
EVENING AS THE SURFACE HIGH ACROSS WESTERN SASKATCHEWAN THIS
MORNING PROPAGATES INTO WESTERN SOUTH DAKOTA FRIDAY MORNING.
GIVEN COOL TEMPERATURES IN THE 40S AND LOWER 50S TO BEGIN THE
EVENING...WIDESPREAD LOWS IN THE UPPER 20S AND LOWER 30S ARE EXPECTED
ACROSS MUCH OF WESTERN AND CENTRAL NORTH DAKOTA TONIGHT WITH
RADIATIONAL COOLING. THUS HAVE ISSUED A FREEZE WARNING FOR MUCH OF
THE AREA LATE TONIGHT INTO FRIDAY MORNING..OUTSIDE OF THE JAMES
RIVER VALLEY AND FAR SOUTH CENTRAL. FOR THESE AREAS...SUFFICIENT
CLOUD COVER IS EXPECTED TO REMAIN THROUGH THE NIGHT TO KEEP LOWS
ABOVE FREEZING. HOWEVER...A FROST ADVISORY MAY BE NEEDED WITH
LATER UPDATES.
.LONG TERM...(FRIDAY THROUGH WEDNESDAY)
ISSUED AT 346 AM CDT THU SEP 11 2014
A MEAN EASTERN PACIFIC/WESTERN U.S RIDGE AND CENTRAL/EASTERN U.S.
TROUGH PATTERN IS EXPECTED TO CONTINUE THROUGH THE LONG TERM PERIOD.
NORTHWEST FLOW OVER THE NORTHERN PLAINS WILL BRING A SERIES OF WEAK
SHORTWAVES DOWN THE LEE OF THE CANADIAN ROCKIES AND INTO THE
FORECAST AREA...KEEPING DAYTIME HIGH TEMPERATURES MAINLY IN THE
60S...WITH A THREAT OF PATCHY FROST EACH MORNING INTO EARLY NEXT
WEEK. THE WESTERN RIDGE FINALLY TRANSLATES INLAND NEXT WEEK BRINGING
UPPER LEVEL RIDGING AND WARMER TEMPERATURES...MAINLY 70S...TO THE
FORECAST AREA NEXT TUESDAY THROUGH THURSDAY. COULD SEE AN ISOLATED
SHOWER ALONG THE INTERNATIONAL BORDER SATURDAY EVENING...OTHERWISE
DRY CONDITIONS ARE ANTICIPATED THROUGH THE EXTENDED PERIOD.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z FRIDAY AFTERNOON)
ISSUED AT 1146 AM CDT THU SEP 11 2014
ISOLATED SHOWERS WILL DEVELOP OVER WESTERN AND CENTRAL NORTH
DAKOTA THIS AFTERNOON. WILL ADD VCSH TO ALL TAF SITES AS A RESULT.
IMPACTS TO SPECIFIC TERMINAL AERODROMES SHOULD BE BRIEF...IF ANY
AT ALL. OTHERWISE...VFR CONDITIONS ARE EXPECTED THROUGH THE
REMAINDER OF THE TAF PERIOD.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
FREEZE WARNING FROM 1 AM CDT /MIDNIGHT MDT/ TO 10 AM CDT /9 AM
MDT/ FRIDAY FOR NDZ001>005-009>013-017>022-031>035-040>044.
&&
$$
UPDATE...TM
SHORT TERM...AYD
LONG TERM...TWH
AVIATION...TM
AREA FORECAST DISCUSSION
NWS BISMARCK ND
1006 AM CDT THU SEP 11 2014
.UPDATE...
ISSUED AT 1006 AM CDT THU SEP 11 2014
CLOUDS ARE BEGINNING TO BREAK OVER WESTERN AND CENTRAL NORTH
DAKOTA. TEMPERATURES ARE RESPONDING BY JUMPING INTO THE 40S WITHIN
THE LAST HOUR. BOWMAN RADAR SHOWS ALL RETURNS SOUTH OF THE STATE.
HOWEVER...MAINTAINED CHANCE OF LIGHT RAIN SOUTHWEST THROUGH THE
THE MORNING AS A BAROCLINIC ZONE WILL BE IN THE VICINITY.
ELSEWHERE...THE LATEST ARW AND NMM MESOSCALE MODELS PROG ISOLATED
TO SCATTERED SHOWER ACTIVITY DEVELOPING SOUTHWEST OF THE MISSOURI
RIVER THIS AFTERNOON. THE LATEST HRRR PROGS ISOLATED SHOWERS
DEVELOPING CWA-WIDE THIS AFTERNOON. GIVEN THE PROXIMITY OF THE
MOISTURE AND SUBTLE MUCAPE...WILL KEEP AFTERNOON POPS CONFINED TO
AREAS SOUTHWEST OF THE MISSOURI RIVER...SIMILAR TO THE ARW AND NMM
SOLUTIONS. AS A RESULT...CHANGED AFTERNOON WEATHER PRECIP TYPE
WORDING FROM STRATIFORM RAIN TO CONVECTIVE SHOWERS. THE UPDATED
PRODUCTS WILL BE OUT SHORTLY.
UPDATE ISSUED AT 645 AM CDT THU SEP 11 2014
LATEST SATELLITE IMAGERY SHOWS UPPER LEVEL TROUGH DROPPING SOUTH
THROUGH THE NORTHERN ROCKIES WITH STRONG JET EXTENDING FROM THE
BASE OF THE TROUGH EAST INTO THE NORTHERN PLAINS. LATEST RADAR
IMAGERY INDICATES THE MAJORITY OF THE PRECIPITATION REMAINING
SOUTH OF THE FORECAST AREA...WITH FAR SOUTHWEST BOWMAN COUNTY
SEEING SOME LIGHT RETURNS. MADE SOME MINOR ADJUSTMENTS TO
POPS...CONFINING THEM TO THE FAR SOUTHWEST EARLY THIS MORNING. IF
WE SEE SOME BREAKS IN THE CLOUDS TODAY...STRONG LOW LEVEL LAPSE
RATES SHOULD AID IN SHOWER DEVELOPMENT FARTHER NORTH AND EAST.
LATEST HRRR DEVELOPS ISOLATED CONVECTION ACROSS THE CWA BY THIS
AFTERNOON. FOR NOW WILL KEEP POPS LIMITED TO THE SOUTHWEST QUARTER
AS PREVIOUSLY FORECAST.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 346 AM CDT THU SEP 11 2014
FREEZING TEMPERATURES TONIGHT HIGHLIGHT THE SHORT TERM FORECAST.
THE 00 UTC DETERMINISTIC SUITE SUGGESTS THE CURRENT STRATUS DECK
IN PLACE THIS MORNING ACROSS WESTERN AND CENTRAL NORTH DAKOTA WILL
BEGIN TO CLEAR ACROSS THE FAR NORTH LATE THIS AFTERNOON. THE
CLEARING TREND IS FORECAST TO CONTINUE TO PUSH SOUTH THROUGH THE
EVENING AS THE SURFACE HIGH ACROSS WESTERN SASKATCHEWAN THIS
MORNING PROPAGATES INTO WESTERN SOUTH DAKOTA FRIDAY MORNING.
GIVEN COOL TEMPERATURES IN THE 40S AND LOWER 50S TO BEGIN THE
EVENING...WIDESPREAD LOWS IN THE UPPER 20S AND LOWER 30S ARE EXPECTED
ACROSS MUCH OF WESTERN AND CENTRAL NORTH DAKOTA TONIGHT WITH
RADIATIONAL COOLING. THUS HAVE ISSUED A FREEZE WARNING FOR MUCH OF
THE AREA LATE TONIGHT INTO FRIDAY MORNING..OUTSIDE OF THE JAMES
RIVER VALLEY AND FAR SOUTH CENTRAL. FOR THESE AREAS...SUFFICIENT
CLOUD COVER IS EXPECTED TO REMAIN THROUGH THE NIGHT TO KEEP LOWS
ABOVE FREEZING. HOWEVER...A FROST ADVISORY MAY BE NEEDED WITH
LATER UPDATES.
.LONG TERM...(FRIDAY THROUGH WEDNESDAY)
ISSUED AT 346 AM CDT THU SEP 11 2014
A MEAN EASTERN PACIFIC/WESTERN U.S RIDGE AND CENTRAL/EASTERN U.S.
TROUGH PATTERN IS EXPECTED TO CONTINUE THROUGH THE LONG TERM PERIOD.
NORTHWEST FLOW OVER THE NORTHERN PLAINS WILL BRING A SERIES OF WEAK
SHORTWAVES DOWN THE LEE OF THE CANADIAN ROCKIES AND INTO THE
FORECAST AREA...KEEPING DAYTIME HIGH TEMPERATURES MAINLY IN THE
60S...WITH A THREAT OF PATCHY FROST EACH MORNING INTO EARLY NEXT
WEEK. THE WESTERN RIDGE FINALLY TRANSLATES INLAND NEXT WEEK BRINGING
UPPER LEVEL RIDGING AND WARMER TEMPERATURES...MAINLY 70S...TO THE
FORECAST AREA NEXT TUESDAY THROUGH THURSDAY. COULD SEE AN ISOLATED
SHOWER ALONG THE INTERNATIONAL BORDER SATURDAY EVENING...OTHERWISE
DRY CONDITIONS ARE ANTICIPATED THROUGH THE EXTENDED PERIOD.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z FRIDAY MORNING)
ISSUED AT 645 AM CDT THU SEP 11 2014
GENERALLY VFR STRATUS WILL PERSIST THROUGH MORNING ACROSS WESTERN
AND CENTRAL NORTH DAKOTA...BEFORE SLOWLY CLEARING FROM NORTH TO
SOUTH LATE THIS AFTERNOON AND INTO THE EVENING. CANNOT RULE OUT A
BRIEF PERIOD OF MVFR CONDITIONS IN STRATUS...WITH LIGHT RAIN
POSSIBLY MIXED WITH SNOW THIS MORNING AT KDIK.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
FREEZE WARNING FROM 1 AM CDT /MIDNIGHT MDT/ TO 10 AM CDT /9 AM
MDT/ FRIDAY FOR NDZ001>005-009>013-017>022-031>035-040>044.
&&
$$
UPDATE...TM
SHORT TERM...AYD
LONG TERM...TWH
AVIATION...AYD
AREA FORECAST DISCUSSION
NWS BISMARCK ND
645 AM CDT THU SEP 11 2014
.UPDATE...
ISSUED AT 645 AM CDT THU SEP 11 2014
LATEST SATELLITE IMAGERY SHOWS UPPER LEVEL TROUGH DROPPING SOUTH
THROUGH THE NORTHERN ROCKIES WITH STRONG JET EXTENDING FROM THE
BASE OF THE TROUGH EAST INTO THE NORTHERN PLAINS. LATEST RADAR
IMAGERY INDICATES THE MAJORITY OF THE PRECIPITATION REMAINING
SOUTH OF THE FORECAST AREA...WITH FAR SOUTHWEST BOWMAN COUNTY
SEEING SOME LIGHT RETURNS. MADE SOME MINOR ADJUSTMENTS TO
POPS...CONFINING THEM TO THE FAR SOUTHWEST EARLY THIS MORNING. IF
WE SEE SOME BREAKS IN THE CLOUDS TODAY...STRONG LOW LEVEL LAPSE
RATES SHOULD AID IN SHOWER DEVELOPMENT FARTHER NORTH AND EAST.
LATEST HRRR DEVELOPS ISOLATED CONVECTION ACROSS THE CWA BY THIS
AFTERNOON. FOR NOW WILL KEEP POPS LIMITED TO THE SOUTHWEST QUARTER
AS PREVIOUSLY FORECAST.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 346 AM CDT THU SEP 11 2014
FREEZING TEMPERATURES TONIGHT HIGHLIGHT THE SHORT TERM FORECAST.
THE 00 UTC DETERMINISTIC SUITE SUGGESTS THE CURRENT STRATUS DECK
IN PLACE THIS MORNING ACROSS WESTERN AND CENTRAL NORTH DAKOTA WILL
BEGIN TO CLEAR ACROSS THE FAR NORTH LATE THIS AFTERNOON. THE
CLEARING TREND IS FORECAST TO CONTINUE TO PUSH SOUTH THROUGH THE
EVENING AS THE SURFACE HIGH ACROSS WESTERN SASKATCHEWAN THIS
MORNING PROPAGATES INTO WESTERN SOUTH DAKOTA FRIDAY MORNING.
GIVEN COOL TEMPERATURES IN THE 40S AND LOWER 50S TO BEGIN THE
EVENING...WIDESPREAD LOWS IN THE UPPER 20S AND LOWER 30S ARE EXPECTED
ACROSS MUCH OF WESTERN AND CENTRAL NORTH DAKOTA TONIGHT WITH
RADIATIONAL COOLING. THUS HAVE ISSUED A FREEZE WARNING FOR MUCH OF
THE AREA LATE TONIGHT INTO FRIDAY MORNING..OUTSIDE OF THE JAMES
RIVER VALLEY AND FAR SOUTH CENTRAL. FOR THESE AREAS...SUFFICIENT
CLOUD COVER IS EXPECTED TO REMAIN THROUGH THE NIGHT TO KEEP LOWS
ABOVE FREEZING. HOWEVER...A FROST ADVISORY MAY BE NEEDED WITH
LATER UPDATES.
.LONG TERM...(FRIDAY THROUGH WEDNESDAY)
ISSUED AT 346 AM CDT THU SEP 11 2014
A MEAN EASTERN PACIFIC/WESTERN U.S RIDGE AND CENTRAL/EASTERN U.S.
TROUGH PATTERN IS EXPECTED TO CONTINUE THROUGH THE LONG TERM PERIOD.
NORTHWEST FLOW OVER THE NORTHERN PLAINS WILL BRING A SERIES OF WEAK
SHORTWAVES DOWN THE LEE OF THE CANADIAN ROCKIES AND INTO THE
FORECAST AREA...KEEPING DAYTIME HIGH TEMPERATURES MAINLY IN THE
60S...WITH A THREAT OF PATCHY FROST EACH MORNING INTO EARLY NEXT
WEEK. THE WESTERN RIDGE FINALLY TRANSLATES INLAND NEXT WEEK BRINGING
UPPER LEVEL RIDGING AND WARMER TEMPERATURES...MAINLY 70S...TO THE
FORECAST AREA NEXT TUESDAY THROUGH THURSDAY. COULD SEE AN ISOLATED
SHOWER ALONG THE INTERNATIONAL BORDER SATURDAY EVENING...OTHERWISE
DRY CONDITIONS ARE ANTICIPATED THROUGH THE EXTENDED PERIOD.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z FRIDAY MORNING)
ISSUED AT 645 AM CDT THU SEP 11 2014
GENERALLY VFR STRATUS WILL PERSIST THROUGH MORNING ACROSS WESTERN
AND CENTRAL NORTH DAKOTA...BEFORE SLOWLY CLEARING FROM NORTH TO
SOUTH LATE THIS AFTERNOON AND INTO THE EVENING. CANNOT RULE OUT A
BRIEF PERIOD OF MVFR CONDITIONS IN STRATUS...WITH LIGHT RAIN
POSSIBLY MIXED WITH SNOW THIS MORNING AT KDIK.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
FREEZE WARNING FROM 1 AM CDT /MIDNIGHT MDT/ TO 10 AM CDT /9 AM
MDT/ FRIDAY FOR NDZ001>005-009>013-017>022-031>035-040>044.
&&
$$
UPDATE...TWH
SHORT TERM...AYD
LONG TERM...TWH
AVIATION...AYD
AREA FORECAST DISCUSSION
NWS BISMARCK ND
1251 AM CDT THU SEP 11 2014
.UPDATE...
ISSUED AT 1249 AM CDT THU SEP 11 2014
NO SIGNIFICANT CHANGES WITH THIS FORECAST UPDATE. THE BEST CHANCE
FOR PRECIPITATION THE REMAINDER OF THE NIGHT IS ACROSS THE FAR
SOUTHWEST IN ASSOCIATION WITH THE UPPER LEVEL LOW ACROSS CENTRAL
MONTANA THAT WILL CONTINUE TO PROPAGATE SOUTHEAST THROUGH THE
NIGHT. LIGHT SNOW MAY MIX WITH RAIN SOUTHWEST...HOWEVER NO
ACCUMULATIONS ARE EXPECTED. GIVEN CLOUD COVER...MAY CANCEL THE
FROST ADVISORY ACROSS THE TURTLE MOUNTAINS AREA THIS
MORNING...FOCUSING ANY FROST AND FREEZE HEADLINES FOR THURSDAY
NIGHT INTO FRIDAY MORNING WITH THE NEXT UPDATE.
UPDATE ISSUED AT 912 PM CDT WED SEP 10 2014
LATEST WATER VAPOR IMAGERY SHOWS A SHORTWAVE ROTATING THROUGH
SOUTHWEST NORTH DAKOTA. UPWARD VERTICAL MOTION ASSOCIATED WITH
THIS SHORTWAVE ALONG WITH THE LEFT EXIT REGION OF AN UPPER JET
ACROSS SOUTHERN NORTH DAKOTA IS PRODUCING SCATTERED RAIN
SHOWERS...WITH AN ISOLATED/BRIEF PERIOD OF SLEET WITHIN THE
STRONGEST VERTICAL MOTION FIELD. THIS WILL CONTINUE TO MOVE INTO
THE JAMES RIVER VALLEY THROUGH THIS LATE EVENING.
OTHERWISE...THE NEXT AREA OF PRECIPITATION WITH FORCING MECHANISMS
VERY SIMILAR TO WHAT WAS MENTIONED ABOVE...IS PROPAGATING THROUGH
SOUTHERN/SOUTHEASTERN MONTANA AT THIS TIME. THE HIGHEST POPS/LIKELY
CATEGORY...WILL JUST GRAZE THE FAR SOUTHWEST PER NAM/RAP OVERNIGHT.
SCATTERED RAIN SHOWERS SEEMS MORE APPROPRIATE...WITH SOME SNOW
POSSIBLY MIXED IN AT TIMES.
DEWPOINTS IN THE TURTLE MOUNTAINS HAVE NOW RISEN INTO THE LOWER
30S. DESPITE SOME CLEARING FROM TIME TO TIME...SATELLITE IMAGERY
AND SURFACE OBS STILL INDICATE ENOUGH CLOUD COVER UPSTREAM TO KEEP
TEMPERATURES ABOVE FREEZING OVERNIGHT. BELIEVE THE FROST ADVISORY
IS IN GOOD STANDING AND WILL NOT MAKE ANY CHANGES AT THIS TIME.
UPDATE ISSUED AT 618 PM CDT WED SEP 10 2014
THE LATEST VISIBLE SATELLITE IMAGERY AND SURFACE OBSERVATIONS SHOW
A CLOUDY SKY ACROSS WESTERN AND CENTRAL NORTH DAKOTA WITH THE
EXCEPTION OF RUGBY AND ROLLA WHERE A STRONGER NORTHEAST FLOW IS
ERODING A CLOUD SHIELD ADVANCING EAST FROM WESTERN NORTH DAKOTA.
THERE ARE MORE HOLES IN THE OVERCAST CONDITIONS ACROSS SOUTHEAST
SASKATCHEWAN AND WESTERN MANITOBA. THE CURRENT FROST ADVISORY AREA
LOOKS ON TRACK AT THIS TIME. WILL MONITOR FOR ADDITIONAL CLEARING
FARTHER WEST AND SEE HOW TEMPERATURES REACT THIS EVENING...GIVEN
DEWPOINTS ARE IN THE UPPER 20S IN THE TURTLE MOUNTAINS. THIS COULD
BECOME A BIGGER CONCERN WITH COLDER LOW TEMPERATURES IF THE SKY
GRID TRENDS CLEARER THAN EXPECTED WITH A CONTINUED NORTHEAST
WIND. HOWEVER AT THIS TIME...FEEL ENOUGH CLOUDS UPSTREAM WILL NEGATE
A POTENTIAL FREEZE WARNING IN THE NORTHEAST...BUT WILL MONITOR
THIS EVENING.
REPORTS OF SOME SNOW MIXED IN WITH THE RAIN AT BEACH LATE THIS
AFTERNOON...ALSO AT NEW ENGLAND AND IN AMIDON. SURFACE TEMPERATURE
ROUGHLY AT 36F FOR THIS MIX TO OCCUR. THIS IS ASSOCIATED WITH A
SHORTWAVE EJECTING OUT OF THE WEST. NORTHEAST WINDS IN CENTRAL
NORTH DAKOTA CONTINUE TO ERODE THE LEADING EDGE OF THIS AREA
SHOWERS. HOWEVER...AN ISOLATED MENTION FROM BISMARCK/MANDAN EAST
INTO THE SOUTHERN JAMES RIVER VALLEY IS WARRANTED PER CURRENT
REFLECTIVITY`S AND HIGH RESOLUTION SOLUTIONS OF THE HRRR AND RAP
WHICH SLIDES A WEAK AREA THROUGH THIS EVENING. MINOR ADJUSTMENTS
TO TEMPERATURES AND DEWPOINTS AS WELL AS POPS THIS EVENING. REST
OF FORECAST REMAINS ON TRACK.
UPDATE ISSUED AT 437 PM CDT WED SEP 10 2014
QUICK UPDATE TO EXPAND AN ISOLATED MENTION OF RAIN SHOWERS THROUGH
SOUTH CENTRAL NORTH DAKOTA THIS EVENING. LATEST BISMARCK AND
BOWMAN RADARS SHOWING AN AREA OF LIGHT RAIN SHOWERS MOVING EAST
OUT OF THE SOUTHWEST. A MID LEVEL CIRCULATION LOCATED IN THE WEST
WILL SLIDE EAST EARLY THIS EVENING...AND CONCUR WITH HIGHER
RESOLUTION MODELS OF THE RAP AND HRRR...THIS PRECIPITATION WEAKENS
BUT ALSO EXPANDS INTO SOUTH CENTRAL NORTH DAKOTA INCLUDING THE SOUTHERN
JAMES RIVER VALLEY BETWEEN 00Z AND 03Z.
&&
.SHORT TERM...(THIS EVENING THROUGH THURSDAY)
ISSUED AT 255 PM CDT WED SEP 10 2014
THE MAJOR FORECAST CHALLENGE WILL BE THE FROST POTENTIAL TONIGHT.
THE LATEST SHORT RANGE MODEL GUIDANCE CONTINUES TO PROG BOUNDARY
LAYER MOISTURE TO ERODE TO THE SOUTHWEST AS DRIER AIR GETS USHERED
IN FROM THE NORTHEAST. FURTHERMORE...BOUNDARY LAYER WINDS ARE
FORECAST TO WEAKEN TO AROUND 10 KNOTS TONIGHT AS HIGH PRESSURE
SETTLES INTO MONTANA. HOWEVER...THE LATEST GUIDANCE CONTINUES TO
PROG MID-LEVEL MOISTURE/CLOUDS (USING 850MB-500MB LAYER RH FIELDS)
TO STREAM OVER MOST OF WESTERN AND CENTRAL NORTH DAKOTA TONIGHT
AHEAD OF A SHORTWAVE ROTATING INTO MONTANA. THIS WOULD LIKELY
INHIBIT COOLING TEMPERATURES.
BALANCING WHERE THE CLEARING SKIES ARE FORECAST...WINDS WEAKENING
OVERNIGHT...AND BOUNDARY LAYER TEMPERATURES...THINK THE TURTLE
MOUNTAIN AREA WILL HAVE THE BEST CHANCE OF SEEING A FROST BETWEEN
09Z-14Z THURSDAY MORNING. AS A RESULT...ISSUED A FROST ADVISORY FOR
BOTTINEAU...ROLETTE...AND PIERCE COUNTIES FOR SAID TIME PERIOD.
TO THE SOUTHWEST...THERE WILL BE A CHANCE FOR A RAIN/SNOW MIX AFTER
MIDNIGHT. HOWEVER...ACCUMULATIONS SHOULD BE LIGHT.
FOR THURSDAY...DEEP MOISTURE AND ASSOCIATED PRECIP CHANCES WILL
CONTINUE TO PUSH SOUTH OF THE STATE AS HIGH PRESSURE BUILDS INTO THE
REGION. WELL BELOW NORMAL HIGHS ARE EXPECTED ONCE AGAIN WITH
READINGS RANGING FROM THE MID 40S SOUTHWEST TO THE MID 50S EAST.
.LONG TERM...(THURSDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 255 PM CDT WED SEP 10 2014
FOCUS IN THE LONG TERM WILL BE ON THE POTENTIAL FOR WIDESPREAD FROST
AND A FREEZE FRIDAY MORNING.
MODEL GUIDANCE CONTINUES TO SHOW LOWS IN THE UPPER 20S ACROSS THE
WEST AND LOWER 30S ELSEWHERE. WITH A LARGE SURFACE HIGH OVER THE
NORTHERN PLAINS WINDS WILL BE LIGHT. THE BIGGEST QUESTION WILL BE
HOW FAST CLOUDS CLEAR OUT. DEEP MOISTURE ACROSS THE STATE WILL BEGIN
TO CLEAR OUT QUICKLY AROUND 18 UTC THURSDAY...HOWEVER THE 12 UTC
MODEL GUIDANCE SHOWS A THIN LAYER OF LOW TO MID LEVEL MOISTURE
HANGING AROUND THROUGH 06 UTC FRIDAY.
REGARDLESS AT LEAST PATCHY FROST SEEMS LIKELY ACROSS CENTRAL AND
WESTERN NORTH DAKOTA. WIDESPREAD FROST IS LOOKING THE MOST LIKELY
ACROSS THE NORTHWEST AS CLOUD COVER WILL CLEAR FROM NORTH TO
SOUTH. THE NORTH WILL ALSO HAVE THE BEST OPPORTUNITY FOR A FREEZE AS
LOWS WILL MOSTLY BE BELOW FREEZING...ESPECIALLY NORTHWEST. AS FOR
THE SOUTH HAVE LIMITED THE WORDING FOR FROST AT AREAS FOR NOW AS
CLOUD COVER MAY STICK AROUND LONG ENOUGH TO PREVENT WIDESPREAD FROST
DEVELOPMENT. FOR THE SAME REASON THERE IS LESS OF A CHANCE OF A
FREEZE ACROSS THE SOUTH. TEMPERATURES WILL ALSO DROP LOW ENOUGH ON
SATURDAY MORNING ACROSS THE SOUTH...ESPECIALLY FOR THE
SOUTHWEST...FOR SOME PATCHY FROST.
FOR THE REMAINDER OF THE LONG TERM THE 12 UTC MODEL GUIDANCE
CONTINUES TO SHOW A MEAN TROUGH OVER THE U.S. THE 12 UTC GFS AND
ECMWF SHOW ANOTHER SHORT WAVE RIDING DOWN THE LEE OF THE CANADIAN
ROCKIES INTO THE NORTHERN PLAINS LATE SATURDAY INTO SUNDAY. MODELS
ARE NOT SHOWING MUCH PRECIPITATION WITH THIS SYSTEM AND THE
REMAINDER OF THE LONG TERM IS ALSO LOOKING MOSTLY DRY AND WARMER.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z THURSDAY NIGHT)
ISSUED AT 1250 AM CDT THU SEP 11 2014
MVFR CEILINGS AT KDIK WILL CONTINUE THROUGH THE NIGHT...WITH
SCATTERED LIGHT RAIN SHOWERS POSSIBLY MIXED WITH SNOW. OTHERWISE
GENERALLY VFR STRATUS WILL PERSIST THROUGH THE NIGHT AND THROUGH
THE MORNING ACROSS WESTERN AND CENTRAL NORTH DAKOTA...BEFORE
SLOWLY CLEARING FROM NORTH TO SOUTH LATE THIS AFTERNOON AND INTO
THE EVENING.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
FROST ADVISORY FROM 4 AM TO 9 AM CDT THIS MORNING FOR NDZ004-005-
013.
&&
$$
UPDATE...AYD
SHORT TERM...TM
LONG TERM...MM
AVIATION...AYD
AREA FORECAST DISCUSSION
NWS GRAND FORKS ND
1143 PM CDT WED SEP 10 2014
.UPDATE...
ISSUED AT 1143 PM CDT WED SEP 10 2014
TWEAKED TEMPS A BIT BUT WILL KEEP THE FROST HEADLINES GOING.
A FEW SPOTS IN THE EASTERN COUNTIES HAVE ALREADY DROPPED INTO THE
30S BUT WITH INCREASING CLOUDS THAT SHOULD SLOW DOWN A BIT.
NORTHWESTERN COUNTIES MAY NOT MAKE ADVISORY CRITERIA BUT WITH THE
POSSIBILITY OF A FEW BREAKS IN THE CLOUDS AM RELUCTANT TO END IT
EARLY. BUMPED UP POPS IN THE FAR SOUTHWEST AS THERE HAVE BEEN SOME
DECENT RADAR RETURNS ALTHOUGH REPORTS OF RAIN REACHING THE GROUND
HAVE BEEN HIT OR MISS.
UPDATE ISSUED AT 947 PM CDT WED SEP 10 2014
TEMPS CONTINUE TO BE THE MAIN QUESTION. MOST LOCATIONS HAVE STAYED
IN THE 40S...ALTHOUGH FOSSTON HAS DROPPED DOWN TO 37 WITH LESS
CLOUD COVER IN THAT AREA AND THAT SITES TYPICAL COLD BIAS. DEW
POINTS EARLIER THIS EVENING WERE IN THE UPPER 20S IN SOME
SPOTS...BUT THERE HAS BEEN AN UPWARD TREND AND CLOUDS CONTINUE TO
INCREASE FROM THE WEST. THERE COULD BE SOME BREAKS IN THE CLOUDS
AND LIGHT ENOUGH WINDS TO DROP A FEW SPOTS INTO THE MID TO LOW
30S. THE DEW POINTS ARE LOWEST IN THE NORTHWESTERN COUNTIES BUT
THE CLOUD COVER IS LESS IN THE NORTHEAST...SO THESE AREAS CONTINUE
TO BE MOST LIKELY TO SEE THE LOW TEMPERATURES. WILL KEEP THE FROST
ADVISORY GOING FOR NOW.
DOWN OVER THE SOUTHWESTERN COUNTIES...RADAR RETURNS HAVE BEEN
ENTERING THE AREA AS A WEAK SHORTWAVE PASSES THROUGH. NOT TOO MUCH
REACHING THE GROUND SO WILL KEEP POPS IN THE 20-30 PERCENT RANGE.
THE PRECIP SHOULD TAPER OFF AFTER MIDNIGHT.
UPDATE ISSUED AT 645 PM CDT WED SEP 10 2014
MADE A FEW MINOR TWEAKS TO POPS AS SHORT RANGE MODELS LIKE THE
HRRR AND THE RAP TREND TOWARDS BRINGING SOME SHOWERS FROM
SOUTHWESTERN ND INTO OUR FAR SOUTHWESTERN COUNTIES. NOT HUGELY
IMPRESSED WITH SIGNIFICANT PRECIP CHANCES...BUT INCLUDED A
ISOLATED MENTION IN THE FAR SOUTHWEST IN CASE SOME SPRINKLES MOVE
INTO RANSOM OR SARGENT COUNTIES. WILL HOLD ONTO FROST HEADLINES
AND CURRENT TEMPS FOR NOW AND TAKE A SECOND LOOK ONCE THE SUN
SETS.
&&
.SHORT TERM...(THIS EVENING THROUGH THURSDAY NIGHT)
ISSUED AT 258 PM CDT WED SEP 10 2014
MAIN FORECAST CHALLENGE WILL BE FROST POTENTIAL THE NEXT FEW
NIGHTS. AS OF MID AFTERNOON SEEING MORE SUN THAN HAD EARLIER
ANTICIPATED. BASICALLY SEEING WEST TO EAST MID LEVEL FLOW WITH
SOME MID LEVEL CLOUDS DRIFTING OVER THE FA. MEANWHILE DRY
NORTHEAST WINDS CONTINUE TO ERODE THE LOWER CLOUDS OVER PORTIONS
OF THE NORTHERN AND EASTERN FA. WINDS ARE STILL PRETTY GUSTY BUT
THESE SHOULD BEGIN TO DECREASE THRU THE EVENING. SHOULD SEE THE
MOST DECREASE IN WINDS LATE...THEREFORE MUCH OF THIS FORECAST
HINGES ON CLOUD COVER. THINK THAT THERE WILL BE SOME CLOUD COVER
OVER THE AREA TONIGHT AND MAYBE MORE SO ACROSS THE SOUTH. WITH
TEMPS ALREADY SO COOL THINK THAT ALL IT WILL TAKE IS AN HOUR OR
SO WITH NO CLOUDS FOR TEMPS TO QUICKLY PLUMMET. THEREFORE DROPPED
LOWS A FEW MORE DEGREES IN THE EAST TO GO ALONG WITH THE EXPECTED
COOLER TEMPS IN THE NORTHWEST. WILL GO WITH A FROST ADVISORY FOR
BOTH AREAS...ESSENTIALLY THE NORTHWEST EDGE OF THE FA AND THE
EASTERN EDGE. IN BETWEEN MAY BE CLOSE AND WILL LET THE EVENING
SHIFT KEEP AN EYE ON THAT. SEEMS LIKE WE TRADITIONALLY MISS THE
FIRST FROST BECAUSE IT IS SO SPOTTY. THIS MAY BE THE CASE THIS
TIME TOO...WITH SOME COLD SPOTS AND FROST WITH SOME WARMER SPOTS
CLOSE BY. WILL CONTINUE TO SEE THE WESTERLY MID LEVEL FLOW ON THU
SO WILL STICK WITH MORE CLOUDS TO THE SOUTH AND LESS NORTH...BUT
AGAIN A TOUGH CALL. MORE OF THE AREA WILL PROBABLY BE UNDER THE
GUN THU NIGHT BUT THINK AREAS ALONG AND NORTH OF HIGHWAY 2 MAY
HAVE THE BEST CHANCE OF FROST.
.LONG TERM...(FRIDAY THROUGH WEDNESDAY)
ISSUED AT 258 PM CDT WED SEP 10 2014
SFC HIGH WILL DRIFT SOUTH OF THE AREA FOR FRI INTO SAT. THERE MAY
STILL BE SOME FROST POSSIBLE FRI NIGHT BUT RETURN SOUTH-SW FLOW
WILL DEVELOP. THEREFORE WIND AND CLOUDS WILL REMAIN THE MAIN
CHALLENGE. KEPT A DRY FORECAST SAT ALTHOUGH SEVERAL MODELS SHOW
ANOTHER SFC LOW IN THE NORTHWEST FA WITH A LITTLE LIGHT PCPN
AROUND IT.
LONG TERM MODELS IN SIMILAR AGREEMENT WITH UPPER WAVE EXTENDING
ACROSS S CNTRL CANADA SUN NIGHT...AND POSITION OF SFC HIGH IN MUCH
BETTER AGREEMENT (THAN YESTERDAYS 12Z RUNS) BETWEEN THE GFS/ECMWF.
BOTH MODELS INDICATING MOSTLY DRY WX AS SFC FRONT MOVES ACROSS MB
AND CLIPS THE NORTHERN VALLEY. CONSALL DOES SHOW LOW POPS OVER
NORTHEAST AS BOTH MODELS HAVE PRECIP OVER NE MN SAT NIGHT. SFC HIGH
THEN DOMINATES AREA FOR MON AND TUE OF NEXT WEEK AS DRY AND COOL WX
CONTINUES. RETURN FLOW SETS UP ON TUE...CAUSING A MILD WARMING TREND
BUT DID REMOVE SPOTTY LOW POPS PRODUCED BY CONSALL AS BOTH GFS AND
ECMWF ARE DRY.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z THURSDAY NIGHT)
ISSUED AT 1143 PM CDT WED SEP 10 2014
VFR CONDITIONS WILL CONTINUE THROUGHOUT THE PERIOD WITH MID AND
HIGH LEVEL CLOUDS. TOMORROW THE CIGS COULD DROP TO THE LOWER END
OF VFR BUT ARE NOT EXPECTED TO GO ANY LOWER. NORTH WINDS WILL
CONTINUE BUT SHOULD BE UNDER 12 KTS.
&&
.FGF WATCHES/WARNINGS/ADVISORIES...
ND...FROST ADVISORY FROM 4 AM TO 9 AM CDT THURSDAY FOR NDZ006-007-014.
MN...FROST ADVISORY FROM 4 AM TO 9 AM CDT THURSDAY FOR MNZ005-006-008-
009-013>017-023-024.
&&
$$
UPDATE...JR
SHORT TERM...GODON
LONG TERM...GODON/SPEICHER
AVIATION...JR
AREA FORECAST DISCUSSION
NWS TULSA OK
1154 PM CDT WED SEP 10 2014
.AVIATION...
CONCERNING TAF SITES KTUL/KRVS/KBVO/KMLC/KXNA/KFYV/KFSM.
SCATTERED SHOWERS AND THUNDERSTORMS WILL CONTINUE TO BE POSSIBLE
ACROSS MAINLY SOUTHEAST OKLAHOMA AND NORTHWEST ARKANSAS TONIGHT
INTO THURSDAY MORNING AS A COLD FRONT MOVES THROUGH. BEHIND THE
FRONT...MVFR TO POSSIBLE PERIODS OF IFR CEILINGS ARE EXPECTED TO
OVERSPREAD THE REGION AND REMAIN INTO THE AFTERNOON HOURS. PARTS
OF NORTHEAST OKLAHOMA INTO FAR NORTHWEST ARKANSAS COULD LIFT BACK
TO VFR FOR A FEW HOURS BUT THEN DROP BACK TO MVFR THURSDAY
EVENING. PRECIP CHANCES WILL AGAIN BE POSSIBLE THURSDAY AFTERNOON
AND EVENING AND WILL CARRY PROB30 GROUPS FOR MLC/FSM AND HOLD OFF
FOR NOW ON ADDITIONAL PRECIP MENTIONS ELSEWHERE.
&&
.PREV DISCUSSION... /ISSUED 911 PM CDT WED SEP 10 2014/
..UPDATE...
DISCUSSION...
OUN SOUNDING CONTINUES TO SHOW RELATIVELY MOIST SOUTHWEST WINDS
ABOVE THE FRONT. THIS COULD SUPPORT ELEVATED PRECIPITATION AND
CONVECTION THROUGH THE NIGHT. RAP AND HRRR APPARENTLY SEE THIS AND
ALSO DEVELOP PRECIPITATION LATER IN THE NIGHT. BEST BET IS AGAIN
OVER WEST CENTRAL ARKANSAS INTO SOUTHEAST OKLAHOMA...GENERALLY
ALONG AND SOUTH OF I-40. LOWER CHANCES WILL EXTEND NORTHWARD...BUT
NOT ALL THE WAY TO THE KANSAS BORDER. WILL KEEP CHANCES IN THE
FORECAST FOR FAR NORTHWEST ARKANSAS ALSO.
LIGHT SHOWERS MOVING ACROSS PARTS OF NORTHEAST OK NOW. OTHER
SHOWERS AND ISOLATED THUNDERSTORM REDEVELOPING ALONG I-40 FROM
CHECOTAH TO THE WEST OF OKEMAH.
&&
.PRELIMINARY POINT TEMPS/POPS...
TUL 61 76 61 65 / 40 10 30 50
FSM 70 75 66 71 / 70 50 50 70
MLC 66 75 66 68 / 70 50 60 60
BVO 58 74 58 66 / 20 10 20 40
FYV 63 73 60 67 / 60 40 40 60
BYV 62 72 58 66 / 60 30 40 50
MKO 63 77 63 66 / 50 20 40 60
MIO 59 73 57 66 / 20 10 20 40
F10 63 76 62 65 / 50 20 40 60
HHW 71 80 69 74 / 60 60 70 60
&&
.TSA WATCHES/WARNINGS/ADVISORIES...
OK...NONE.
AR...NONE.
&&
$$
AVIATION...20
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
401 PM EDT THU SEP 11 2014
.SYNOPSIS...
A STRONG COLD WILL MOVE ACROSS THE REGION TODAY. COOL AND DRIER
WEATHER WILL FOLLOW FOR FRIDAY. A NEW DISTURBANCE WILL MOVE
THROUGH THE AREA ON SATURDAY BEFORE HIGH PRESSURE RETURNS FAIR
WEATHER FOR SUNDAY. THE OVERALL PATTERN FAVORS BELOW NORMAL
TEMPERATURES FROM SATURDAY INTO NEXT WEEK.
&&
.NEAR TERM /UNTIL 6 AM FRIDAY MORNING/...
2PM UPDATE...
AS OF 2PM...THE COLD FRONT IS BETWEEN STATE COLLEGE AND ALTOONA
WITH EVEN FEWER SHOWERS ASSOCIATED THAN EARLIER THIS MORNING. THE
UPPER SHORTWAVE IS VERY FLAT AND SHEARED OUT...SO SUPPORT FOR THE
FRONT IS NOT IMPRESSIVE EVEN THOUGH THE AIRMASS DISCONTINUITY IS.
TEMPERATURES HAVE BEEN STEADY OR FALLING OVER NWRN PA ALL DAY
WHILE TEMPS HAVE RISEN INTO THE LOWER 80S OVER THE SERN PART OF
THE AREA.
THE RAP SHOWS VIRTUALLY NO CAPE OR LOW LEVEL CONVERGENCE ALONG
WITH WEAK MID LEVEL LAPSE RATES...AND THE LACK OF SHOWER ACTIVITY
PRETTY MUCH CONFIRMS THIS ANALYZED LACK OF INSTABILITY.
I LOWERED THE OVERALL PROBABILITY OF SHOWERS AND ISOLATED
THUNDERSTORMS OVER MY SERN ZONES AS THE FRONT SWEEPS EAST. THE
NEXT 3-6 HOURS WILL BE THE WINDOW OF BEST OPPORTUNITY FOR RAIN
BEFORE THINGS DRY OUT FOR TONIGHT AND FRIDAY.
THE FRONT WILL PUSH SE OF THE AREA THIS EVENING WITH AN
INITIALLY GUSTY NW FLOW GIVING WAY TO A LIGHTER BREEZE. MODEL
SOUNDINGS SHOW A FAIR AMOUNT OF LOW LEVEL MOISTURE BEING TRAPPED
UNDER A STRENGTHENING SUBSIDENCE INVERSION. LOOKS LIKE LOW CLOUDS
AND EVEN SOME PATCHY FOG WILL REDEVELOP LATER TONIGHT...LASTING
THROUGH THE SUNRISE HOURS OF FRIDAY.
LOWS TONIGHT WILL DIP INTO THE LOW-MID 40S IN VALLEYS OF THE
NORTHERN MOUNTAINS TO NEAR 60 IN THE SE. IF CLOUDS HOLD OFF OR
BREAK UP...WOULD NOT BE SURPRISED TO SEE SOME READINGS IN THE
UPPER 30S AT SOME OF THE NORMAL COLD SPOTS OF THE NORTH.
&&
.SHORT TERM /6 AM FRIDAY MORNING THROUGH FRIDAY NIGHT/...
IT WILL BE DRY FRIDAY BUT IT COULD BE RATHER CLOUDY FOR A TIME
UNTIL THE SUBSIDENCE INVERSION MIXES OUT AND CLOUDS CAN BREAK UP.
HIGHS IN THE 60S TO LOWER 70S WILL AVERAGE SOME 5-10 DEG BELOW
NORMAL.
&&
.LONG TERM /SATURDAY THROUGH THURSDAY/...
A SHORTWAVE TROUGH DIGGING SEWD THROUGH THE NRN HIGH PLAINS THIS
MORNING WILL MOVE EASTWARD AND REACH THE GRT LAKES REGION FRI
NIGHT WHILE CONTINUING TO AMPLIFY...TAKING ON A NEGATIVE TILT AS
IT ACCELERATES NEWD ACROSS THE ST LAWRENCE RIVER VLY ON SAT. THE
ENERGY WILL BE IN SUFFICIENTLY CLOSE PROXIMITY TO THE BAROCLINIC
ZONE OVER THE SOUTHEAST STATES FOR A WAVE OF LOW PRESSURE TO
DEVELOP NEAR THE TN VLY/CNTRL APPLCHNS AND LIFT NEWD THRU UPPER OH
VLY/MID ATLC/NORTHEAST ON SAT. MODEST HEIGHT FALLS AND FAVORABLE
JET DYNAMICS ALOFT SHOULD PROVIDE SUFFICIENT LG SCALE FORCING FOR
LIFT...WHILE STRENGTHENING SLY LLJ/WAA RECOVERS PW VALUES TO 1-1.5
INCHES. MODELS SHOW LITTLE IN THE WAY OF INSTABILITY BUT SOME LOW
TOPPED CONVECTION MAY STILL DEVELOP AND PRODUCE LOCAL 0.25 TO 0.50
QPF AMTS. THE TRAILING FRONT SHOULD BE FAIRLY PROGRESSIVE AS IT
CROSSES THRU THE LOCAL AREA..WHICH SHOULD ALSO ACT TO LIMIT PCPN
AMTS. WITH GOOD AGREEMENT IN THE GUIDANCE OPTED TO INCREASE AREA
OF LKLY POPS FOR D3.
FROM SUNDAY TO NEXT THURSDAY (9/18) THE UPPER PATTERN OVER NOAM
WILL FEATURE A WESTERN RIDGE WITH A DOWNSTREAM MEAN TROUGH OVER
THE EAST. WHILE MOST OF THE PERIOD SHOULD BE DRY UNDER THE
INFLUENCE OF MODIFIED CANADIAN HIGH PRESSURE...THERE SEEMS TO BE
BROAD SUPPORT FOR ANOTHER S/WV AND FRONTAL SYSTEM TO BRING SHOWERS
TO THE AREA IN THE LATE MONDAY/TUESDAY TIME FRAME. OTHERWISE MOST
OF THE ORGANIZED PCPN WILL BE FOCUSED TO THE SOUTH NEAR STALLED
FRONT OVER THE CAROLINAS. THE MEAN PATTERN SUPPORTS BELOW AVG
FALL-LIKE READINGS WITH A FEW CHILLY MORNINGS AND COOL DAYS. SOME
PATCHY FROST IS POSSIBLE IN THE NRN TIER WHICH IS NOT THAT FAR
FROM THE CLIMO.
&&
.AVIATION /19Z THURSDAY THROUGH TUESDAY/...
A COLD FRONT IS MOVING THROUGH THE FLYING AREA. CEILINGS HAVE
LIFTED UP TO VFR FOR THE MOST PART IN THE WARM AIR AHEAD OF THE
FRONT...WHILE BEHIND THE FRONT MVFR AND EVEN AREAS OF IFR ARE
FAIRLY WIDESPREAD IN A PATTERN THAT MORE RESEMBLES THE COLD SEASON
THAN THE LATE SUMMER. THESE LOWER CEILINGS WILL TEND TO LIFT
THROUGH EARLY EVENING WITH MOST SITES BEING VFR BY NIGHTFALL. JST-
BFD ARE USUALLY THE TERMINALS THAT HANG ON TO LOWER CONDITIONS THE
LONGEST AND THIS SHOULD NOT BE AN EXCEPTION.
THERE IS STILL THE POTENTIAL FOR AN ISOLATED HEAVIER SHOWER OR
THUNDERSTORM...WITH LOCALIZED BRIEF FLIGHT RESTRICTIONS...OVER
SERN AREAS AS THE FRONT SWEEPS EAST. THE THREAT WILL DIMINISH
LATER THIS AFTERNOON INTO EARLY EVENING AS THE FRONT MOVES EAST OF
THE AREA.
FORECAST SOUNDINGS SHOW A STRONG LOW LEVEL INVERSION FORMING LATER
TONIGHT AS A SPRAWLING HIGH PRESSURE AREA SPILLS INTO THE REGION.
THIS SHOULD LEAD TO THE REDEVELOPMENT OF SOME LOW CLOUDS AND
POSSIBLY AREAS OF FOG LATER TONIGHT THROUGH THE POST DAWN HOURS
OF FRIDAY MORNING.
OUTLOOK...
FRI...LOW CIGS PSBL EARLY...BCMG VFR.
SAT...VFR/MVFR CIGS WITH SCT SHOWERS.
SUN...PATCHY AM FOG...OTHERWISE VFR.
MON...NO SIG WX.
MON NIGHT - TUE...A COLD FRONT WILL BRING REDUCED CONDITIONS WITH
SHOWERS.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...LA CORTE
NEAR TERM...LA CORTE
SHORT TERM...LA CORTE
LONG TERM...STEINBUGL
AVIATION...LA CORTE
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
205 PM EDT THU SEP 11 2014
.SYNOPSIS...
A STRONG COLD WILL MOVE ACROSS THE REGION TODAY. COOL AND DRIER
WEATHER WILL FOLLOW FOR FRIDAY. A NEW DISTURBANCE WILL MOVE
THROUGH THE AREA ON SATURDAY BEFORE HIGH PRESSURE RETURNS FAIR
WEATHER FOR SUNDAY. THE OVERALL PATTERN FAVORS BELOW NORMAL
TEMPERATURES FROM SATURDAY INTO NEXT WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
2PM UPDATE...
AS OF 2PM...THE COLD FRONT IS BETWEEN STATE COLLEGE AND ALTOONA
WITH EVEN FEWER SHOWERS ASSOCIATED THAN EARLIER THIS MORNING. THE
UPPER SHORTWAVE IS VERY FLAT AND SHEARED OUT...SO SUPPORT FOR THE
FRONT IS NOT IMPRESSIVE EVEN THOUGH THE AIRMASS DISCONTINUITY IS.
TEMPERATURES HAVE BEEN STEADY OR FALLING OVER NWRN PA ALL DAY
WHILE TEMPS HAVE RISEN INTO THE LOWER 80S OVER THE SERN PART OF
THE AREA.
THE RAP SHOWS VIRTUALLY NO CAPE OR LOW LEVEL CONVERGENCE ALONG
WITH WEAK MID LEVEL LAPSE RATES...AND THE LACK OF SHOWER ACTIVITY
PRETTY MUCH CONFIRMS THIS ANALYZED LACK OF INSTABILITY.
I LOWERED THE OVERALL PROBABILITY OF SHOWERS AND ISOLATED
THUNDERSTORMS OVER MY SERN ZONES AS THE FRONT SWEEPS EAST. THE
NEXT 3-6 HOURS WILL BE THE WINDOW OF BEST OPPORTUNITY FOR RAIN
BEFORE THINGS DRY OUT FOR TONIGHT AND FRIDAY.
THE FRONT WILL PUSH SE OF THE AREA THIS EVENING WITH AN
INITIALLY GUSTY NW FLOW GIVING WAY TO A LIGHTER BREEZE. MODEL
SOUNDINGS SHOW A FAIR AMOUNT OF LOW LEVEL MOISTURE BEING TRAPPED
UNDER A STRENGTHENING SUBSIDENCE INVERSION. LOOKS LIKE LOW CLOUDS
AND EVEN SOME PATCHY FOG WILL REDEVELOP LATER TONIGHT...LASTING
THROUGH THE SUNRISE HOURS OF FRIDAY.
LOWS TONIGHT WILL DIP INTO THE LOW-MID 40S IN VALLEYS OF THE
NORTHERN MOUNTAINS TO NEAR 60 IN THE SE. IF CLOUDS HOLD OFF OR
BREAK UP...WOULD NOT BE SURPRISED TO SEE SOME READINGS IN THE
UPPER 30S AT SOME OF THE NORMAL COLD SPOTS OF THE NORTH.
&&
.SHORT TERM /FRIDAY/...
IT WILL BE DRY FRIDAY BUT IT COULD BE RATHER CLOUDY FOR A TIME
UNTIL THE SUBSIDENCE INVERSION MIXES OUT AND CLOUDS CAN BREAK UP.
HIGHS IN THE 60S TO LOWER 70S WILL AVERAGE SOME 5-10 DEG BELOW
NORMAL.
&&
.LONG TERM /FRIDAY NIGHT THROUGH THURSDAY/...
SURFACE HIGH SPLITS FRI NIGHT/SAT WITH A PORTION RUNNING EASTWARD
ACROSS S ONTARIO/NEW ENGLAND WHILE THE MAIN HIGH PRESSURE CENTER
REMAINS CENTERED OVER MISSOURI VALLEY. AT THE SAME TIME...A POTENT
UPPER SHORTWAVE SLIDES EAST ALONG THE U.S./CANADA BORDER TURNING
LOW LEVEL FLOW OVER PA BACK TO THE SOUTH BRIEFLY FRI NIGHT INTO
SAT. INCREASED LOW-MID LEVEL FLOW DURING THIS TIME SHOULD TRIGGER
SCT SHOWERS...THOUGH ACCUMS SHOULD BE LIGHT WITH LIMITED MOISTURE
TO WORK WITH.
LEFT SUNDAY INTO WED DRY.
SOME HINTS OF A WEAK TROUGH OVER THE LAKES EARLY NEXT WEEK...BUT
LEFT FCST DRY FOR NOW.
&&
.AVIATION /18Z THURSDAY THROUGH TUESDAY/...
A COLD FRONT IS MOVING THROUGH THE FLYING AREA. CEILINGS HAVE
LIFTED UP TO VFR FOR THE MOST PART IN THE WARM AIR AHEAD OF THE
FRONT...WHILE BEHIND THE FRONT MVFR AND EVEN AREAS OF IFR ARE
FAIRLY WIDESPREAD IN A PATTERN THAT MORE RESEMBLES THE COLD SEASON
THAN THE LATE SUMMER. THESE LOWER CEILINGS WILL TEND TO LIFT
THROUGH EARLY EVENING WITH MOST SITES BEING VFR BY NIGHTFALL. JST-
BFD ARE USUALLY THE TERMINALS THAT HANG ON TO LOWER CONDITIONS THE
LONGEST AND THIS SHOULD NOT BE AN EXCEPTION.
THERE IS STILL THE POTENTIAL FOR AN ISOLATED HEAVIER SHOWER OR
THUNDERSTORM...WITH LOCALIZED BRIEF FLIGHT RESTRICTIONS...OVER
SERN AREAS AS THE FRONT SWEEPS EAST. THE THREAT WILL DIMINISH
LATER THIS AFTERNOON INTO EARLY EVENING AS THE FRONT MOVES EAST OF
THE AREA.
FORECAST SOUNDINGS SHOW A STRONG LOW LEVEL INVERSION FORMING LATER
TONIGHT AS A SPRAWLING HIGH PRESSURE AREA SPILLS INTO THE REGION.
THIS SHOULD LEAD TO THE REDEVELOPMENT OF SOME LOW CLOUDS AND
POSSIBLY AREAS OF FOG LATER TONIGHT THROUGH THE POST DAWN HOURS
OF FRIDAY MORNING.
OUTLOOK...
FRI...LOW CIGS PSBL EARLY...BCMG VFR.
SAT...VFR/MVFR CIGS WITH SCT SHOWERS.
SUN...PATCHY AM FOG...OTHERWISE VFR.
MON...NO SIG WX.
MON NIGHT - TUE...A COLD FRONT WILL BRING REDUCED CONDITIONS WITH
SHOWERS.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...LA CORTE
NEAR TERM...LA CORTE
SHORT TERM...LA CORTE
LONG TERM...MARTIN
AVIATION...LA CORTE
AREA FORECAST DISCUSSION...UPDATED
NWS ABERDEEN SD
1244 AM CDT THU SEP 11 2014
.UPDATE...
AVIATION DISCUSSION HAS BEEN UPDATED.
A QUICK MOVING SHORT WAVE TROUGH WAS BRINGING SOME LIGHT RAIN SHOWERS
TO THE REGION THIS EVENING. THIS WILL MOVE ON TO THE EAST AFTER MIDNIGHT
WHILE NEW DEVELOPMENT MOVES INTO THE WEST AND SOUTHWEST PARTS OF
THE CWA WITH THE MAIN UPPER LOW PRESSURE TROUGH. ADJUSTED POPS FOR
THE NIGHT...MAINLY ACROSS THE NORTHERN CWA. UPDATED FORECAST.
&&
.PREVIOUS DISCUSSION...
.SHORT TERM...TONIGHT THROUGH FRIDAY NIGHT
CLOUDY AND COLD IS THE STORY ACROSS THE REGION THIS AFTERNOON. IN
FACT...SOME LOCATIONS WILL LIKELY SET RECORDS FOR THE COLDEST
HIGH TEMPERATURE EVER RECORDED ON THIS DATE. CWA IS CURRENTLY DRY
BUT WATCHING THE BEGINNINGS OF THE NEXT SYSTEM MOVING ACROSS
NORTHWEST SD. TREND FOR TONIGHT WILL BE FOR PRECIP TO MAINLY
AFFECT WESTERN AND CENTRAL SD...AND MAY EVEN GET COLD ENOUGH LATE
TONIGHT AND EARLY THURSDAY MORNING TO ALLOW FOR A RAIN/SNOW MIX
ACROSS THE FAR NORTHWEST CWA. TARGET AREA FOR ACCUMULATING SNOW
THOUGH STILL REMAINS OVER FAR WESTERN SD AND THE BLACK HILLS. WILL
HAVE TO WATCH CLOUD COVER TRENDS OVERNIGHT ACROSS THE
NORTHERN/NORTHEAST CWA AS CIGS HAVE THINNED AND HAVE EVEN REVEALED
SOME HOLES. RAP MODEL 925-850MB RH SHOWS THIS DRIER AREA
NICELY...AND BRINGS IN OVER THE NORTHERN COUNTIES LATER TONIGHT.
IF ANY BREAKS OR THINNING OCCUR...TEMPS COULD FALL PRETTY NICELY.
BUT OVERALL...THE ABUNDANCE OF MID AND HIGH CLOUDS WITH THE NEXT
APPROACHING WAVE...AND THE OVERALL WINDS STAYING UP A TOUCH SHOULD
PREVENT THE BOTTOM FROM FALLING OUT ON TEMPS.
ATTENTION THEN TURNS TO THURSDAY NIGHT AND FRIDAY MORNING AND THE
POTENTIAL FOR FROST. MODELS CONTINUE TO SHIFT PRECIP AND CLOUDS A
BIT FURTHER SOUTH AND EAST DURING THIS TIME...A BIT QUICKER THAN
PREVIOUS RUNS...AND THE PREVIOUSLY SLOWER EC IS NOW COMING AROUND
TO THE FASTER SOLUTIONS OTHER MODELS HAVE BEEN SHOWING. THIS MEANS
A BETTER POTENTIAL FOR FROST CONDITIONS AND TEMPS IN THE LOW TO
MID 30S OVER A GOOD PORTION OF THE CWA. INSERTED FROST INTO THE
GRIDS ALONG AND WEST OF THE JAMES VALLEY AND COULD VERY WELL BE
HEADING TOWARDS A FROST ADVISORY AT SOME POINT. IT WILL ALL DEPEND
ON HOW MUCH CLOUD COVER LINGERS OVER THE AREA...THE CLEARER THE
SKIES THE BETTER THE TEMPS WILL FALL.
FOR FRIDAY NIGHT AND SATURDAY...MODELS SEEM TO BE NUDGING THE HIGH
CENTER TO THE EAST A TAD QUICKER. WHAT THIS MEANS IS THAT A
SLIGHTLY STRONGER GRADIENT SETS UP FRIDAY NIGHT WITH SOUTH WINDS
PICKING UP. WHETHER OR NOT THESE WINDS ARE STRONG ENOUGH ALONG AND
EAST OF THE JAMES VALLEY TO PREVENT TEMPS FROM REACHING THE LOW TO
MID 30S IS DOUBTFUL. WEST OF THERE...PROBABLY YES. CANNOT RULE OUT
FROST FRIDAY NIGHT/SATURDAY MORNING EITHER...BUT BEST POTENTIAL
HERE WILL BE ACROSS THE EASTERN CWA.
.LONG TERM...SATURDAY THROUGH WEDNESDAY
NOT MUCH CHANGE IN THE EXTENDED FROM 24 HOURS AGO. 12Z MODEL
SOLUTIONS POINT TO A BIT OF WARMING ON SATURDAY OUT AHEAD OF AN
APPROACHING COLD FRONT. ANOTHER SURFACE HIGH PRESSURE SYSTEM
BUILDS DOWN FOR SUNDAY AND MONDAY...BUT THEN SHIFTS SOUTH AND EAST
OF THE AREA...ALLOWING FOR RETURN FLOW WARMING WINDS TUESDAY AND
WEDNESDAY. PRECIPITATION CHANCES REALLY ARE FEW AND FAR BETWEEN IN
THE OUT PERIODS...WITH THE "BEST" CHANCES FOR A FEW RAIN
SHOWERS SHOWING UP SUNDAY AFTERNOON/EVENING BEHIND THIS COLD
FROPA.
&&
.AVIATION...
06Z TAFS FOR THE KABR...KATY...KPIR AND KMBG TERMINALS
A QUICK MOVING SHORT WAVE TROUGH WILL BRING SOME LIGHT RAIN
SHOWERS TO ATY INTO THE EARLY MORNING HOURS. OTHERWISE...LIFT
FROM THE MAIN UPPER LOW PRESSURE AREA DROPPING IN FROM THE NORTHWEST
TONIGHT AND THURSDAY WILL BRING SHOWERS INTO THE PIERRE AREA THROUGH
THURSDAY MORNING. EXPECT MOST OF THE SHOWERS TO REMAIN AWAY FROM
MBG...ABR AND ATY. CEILINGS ARE EXPECTED TO BE MAINLY VFR FOR MBG
...ABR AND ATY THROUGH THE PERIOD...EXCEPT FOR PIR WHERE THEY SHOULD
BE MAINLY MVFR.
&&
.ABR WATCHES/WARNINGS/ADVISORIES...
SD...NONE.
MN...NONE.
&&
$$
UPDATE...MOHR
SHORT TERM...TMT
LONG TERM...DORN
AVIATION...TDK
WEATHER.GOV/ABERDEEN
AREA FORECAST DISCUSSION
NWS NASHVILLE TN
725 PM CDT FRI SEP 12 2014
.UPDATE...
LATEST SURFACE OBS AND SATELLITE IMAGERY SHOWS LOW CLOUDS
CONTINUE TO BLANKET THE MID STATE...AND ACTUALLY EXTEND NORTHWARD
ALL THE WAY INTO CANADA SO THEY WONT BE GOING ANYWHERE ANYTIME
SOON. WATER VAPOR IMAGERY THIS EVENING DEPICTS A STRONG TROUGH
DIGGING SOUTHWARD INTO IOWA AND MISSOURI. AS THIS TROUGH SWINGS
THROUGH THE OHIO AND TENNESSEE VALLEYS OVERNIGHT...EXPECT A FEW
LIGHT SHOWERS AND SPRINKLES TO BREAK OUT ACROSS THE MID STATE
SIMILAR TO THE MOST RECENT HRRR MODEL RUNS. ALSO ANTICIPATE SOME
PATCHY FOG DEVELOPMENT IN THE HIGHER TERRAIN AREAS OF EASTERN
ZONES AS DEWPOINT DEPRESSIONS LOWER OVERNIGHT. DESPITE EXTENSIVE
CLOUD COVER...CAA WILL INCREASE OVERNIGHT WITH DRIER AIR
ADVECTING IN FROM THE NORTH AT THE SURFACE...WHICH SHOULD ALLOW
TEMPS TO FALL INTO THE UPPER 50S AND LOWER 60S FOR LOWS. CURRENT
FORECAST FOR TONIGHT ALREADY HAS CLOUDS...POPS...AND TEMPS WELL
HANDLED...AND ONLY MADE MINOR CHANGES FOR THE OVERNIGHT PERIOD.
SHAMBURGER
&&
.PREV DISCUSSION... /ISSUED 514 PM CDT FRI SEP 12 2014/
AVIATION 00Z DISCUSSION...
PVA WILL BE IN PLACE THROUGH 12Z OVERNIGHT AS A WEAK MID LEVEL IMPULSE
WILL BE ON APPROACH. AS A RESULT...LOW CIGS WILL PERSIST THROUGH
AT LEAST 12Z. THEREAFTER...THE LOW CLOUDINESS WILL STILL BE RATHER
TOUGH TO DISLODGE. THE MID AND UPPER FLOW STILL CARRIES A WEAK
SOUTHERLY COMPONENT. NEVERTHELESS...CIGS SHOULD BEGIN TO LIFT SOME
TOWARD 18Z WITH PARTIAL CLEARING WEST BY 00Z.
OTW...ISOLATED SHOWERS HERE AND THERE WILL BE POSSIBLE UNTIL 12Z.
HOWEVER...THE EXPECTED COVERAGE DOES NOT WARRANT THE USAGE OF
VCNTY...TEMPO OR PROB GROUPS.
PREV DISCUSSION... /ISSUED 256 PM CDT FRI SEP 12 2014/
DISCUSSION...IT WAS A CLOUDY DAY ACROSS MID TN WITH TEMPERATURES
MAINLY IN THE 70S...WHICH IS 5 TO 10 DEGREES COOLER THAN NORMAL. A
COLD FRONT HAD SETTLED WELL TO OUR SOUTHEAST. HIGH PRESSURE WAS
LOCATED WELL TO OUR NORTHWEST...CENTERED OVER THE NORTHERN PLAINS.
POST FRONTAL MOISTURE LINGERED OVER A WIDE AREA ...AND THIS
MOISTURE AND CLOUDINESS WILL REMAIN FOR A WHILE.
FOR TONIGHT...CLOUDY SKIES MAY EVENTUALLY PRODUCE A FEW LIGHT
SHOWERS OR PATCHY DRIZZLE AS A TROUGH AXIS PASSES ACROSS THE
REGION. THE CLOUDS WILL LOWER...AND SHOULD KEEP ANY FOG FORMATION
FROM BEING VERY DENSE. LOWS WILL BE A FEW DEGREES COOLER THAN
LAST NIGHT.
ON SATURDAY...MODELS SHOW A SMALL CHANCE FOR MORNING SHOWERS
PLATEAU...THEN DECREASING MOISTURE FROM NW TO SE. WE THINK CLOUDS
COULD BE STUBBORN...SO EXPECT OVERCAST SKIES ALL ZONES THROUGH
MIDDAY...THEN PARTIAL CLEARING GRADUALLY WORKING FROM NW TO SE
ACROSS THE MID STATE THROUGH THE AFTERNOON. HIGH TEMPS WILL AGAIN
BE QUITE PLEASANT...IN THE 70S. NORTH BREEZES WILL PICK UP A BIT
TO HELP THE CLEARING TREND. WINDS WILL REACH 10-20 MPH IN THE
EARLY AFTERNOON.
DRY WX WILL CONTINUE THROUGH THE REST OF THE WEEKEND. SATURDAY NIGHT
WILL BE A LITTLE CHILLY...WITH LOWS MAINLY LOWER 50S...BUT SOME
40S POSSIBLE AS WELL. SUNDAY WILL BE MAINLY SUNNY AND TEMPS WILL
RECOVER TO THE UPPER 70S.
LOOKING AHEAD...NEXT WEEK SHOULD BE QUIET IN THE WX DEPARTMENT.
A COUPLE OF WAVES AND FRONTS WILL SWING DOWN IN THE NORTHWEST
FLOW...BUT NO MAJOR RAINFALL OR TEMPERATURE ANOMALIES ARE EXPECTED.
RIGHT NOW...IT LOOKS LIKE THE STRONGEST SYSTEM WILL MOVE THROUGH
TUESDAY NIGHT...AND JUST INCLUDING 20 POPS AT THAT TIME. LOWS NEXT
WEEK WILL BE MOSTLY IN THE UPPER 50S TO AROUND 60...WITH HIGHS IN
THE MID 70S TO LOWER 80S.
13
PREV DISCUSSION... /ISSUED 1233 PM CDT FRI SEP 12 2014/
AVIATION...
MVFR-IFR CIGS ARE EXPECTED TO IMPROVE SLIGHTLY THROUGH THIS
AFTERNOON...BUT PERSISTENT VFR CIGS ARE NOT EXPECTED IN THE NEAR
TERM. WINDS WILL BE STEADY FROM THE NORTH TO NORTHWEST THROUGH THE
NIGHT SO VIS REDUCTIONS ARE NOT ANTICIPATED AT BNA OR CKV. FOR CSV
EXPECT IFR-LIFR VIS AND CIGS AGAIN DURING THE OVERNIGHT...WITH
CONDITIONS IMPROVING AT ALL THREE TAF SITES AFTER 14Z TOMORROW
UNDER A STEADY NORTH TO NORTHEASTERLY FLOW.
&&
.OHX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
55
AREA FORECAST DISCUSSION...UPDATED
NWS FORT WORTH TX
656 PM CDT FRI SEP 12 2014
.UPDATE...
WILL BE ISSUING A FORECAST UPDATE AROUND 7 PM TO ADDRESS POPS FOR
THE EVENING PERIOD. CURRENTLY...88D RADARS ARE SHOWING VERY LITTLE
FALLING OVER THE NORTHERN TWO-THIRDS. THE TT-WRF AND HRRR SHOW
ONLY LIGHT SPOTTY ACTIVITY OVER THIS AREA THIS EVENING...THUS
WILL LOWER POPS TO 20 PERCENT FOR LIGHT SHOWERS/DRIZZLE.
AS FOR THE SOUTHEAST COUNTIES WHERE THE COLD FRONT AND AN EASTERLY
WAVE INTERACTED EARLIER THIS AFTERNOON...THE HI-RES SOLUTIONS
INDICATED THAT THE SCATTERED TO NUMEROUS SHOWERS/THUNDERSTORMS
WILL CONTINUE THROUGHOUT THE EVENING BEFORE WANING AFTER MIDNIGHT.
THUNDERSTORMS ALONG AND SOUTHEAST OF A CAMERON TO PALESTINE LINE
WILL BE CAPABLE OF 1-2 INCHES RAINFALL...DANGEROUS LIGHTNING AND SOME
WIND GUST POTENTIAL UP TO 30 MPH. THE REST OF THE FORECAST
REMAINS UNCHANGED. 75
&&
.AVIATION...
/ISSUED 643 PM CDT FRI SEP 12 2014/
CIGS HAVE BEEN LIFTING DURING THE LAST FEW HOURS AS DRIER AIR
ENTERS THE REGION AND THE FRONTAL LAYER DEEPENS. WITH LOWER
DEWPOINTS AND HIGHER CIGS FARTHER TO THE NORTH...BELIEVE CIGS
WILL PROBABLY HAVE DIFFICULTY DROPPING AFTER SUNSET. HOWEVER IF
DRIZZLE OR AREAS OF HEAVIER PRECIP DOES FORM DURING THE NEXT FEW
HOURS...THIS WOULD HAVE THE AFFECT OF SATURATING THE LOW LEVELS
AND LOWERING CIGS AGAIN TO IFR OR POSSIBLY LOWER. FOR NOW THIS
POSSIBILITY LOOKS LOW BUT WILL CONTINUE TO MONITOR.
FOR THE TAFS HAVE DRY CONDITIONS AND MVFR PREVAILING THROUGH
EARLY AFTERNOON TOMORROW...WITH MOS GUIDANCE LIKELY A BIT TOO
QUICK IN LIFTING CIGS DUE TO WHAT IS MORE TYPICAL OF THE TIME OF
YEAR. THIS AIRMASS IS SIGNIFICANTLY COLDER THAN NORMAL SO THIS
STRATUS MAY BE A BIT MORE STUBBORN THAN NORMAL SEPTEMBER STRATUS.
WILL INCLUDE A TEMPO FOR IFR CIGS AROUND DAYBREAK...BUT AGAIN
CONFIDENCE IN THIS IS A LITTLE LOW. OTHERWISE NORTH WINDS WILL
PREVAIL NEAR 10-20KT THROUGH MIDDAY TOMORROW.
FOR WACO HAVE INDICATED SLIGHTLY LOWER CIGS AND THUS AN IFR
FORECAST FROM OVERNIGHT THROUGH MID MORNING AS THE FRONTAL LAYER
IS MORE SHALLOW THERE. NO PRECIPITATION IS MENTIONED...AS IT
SHOULD STAY JUST TO THE SOUTHEAST.
TR.92
&&
.PREV DISCUSSION... /ISSUED 245 PM CDT FRI SEP 12 2014/
THE COLD FRONT IS CURRENTLY MOVING INTO CENTRAL AND EAST TEXAS.
AREAS SOUTHEAST OF A TEMPLE...MEXIA...ATHENS LINE WILL LIKELY SEE
THE MOST INSTABILITY AND POTENTIAL FOR SHOWERS AND STORMS THROUGH
SUNSET THIS EVENING. BEHIND THE COLD FRONT...STRONG COLD ADVECTION
AND PERSISTENT STRATUS AND DRIZZLE WERE OCCURRING. SCATTERED SHOWERS
WERE CONTINUING ACROSS THE NORTHEAST COUNTIES. COMBINED WITH THE
BRISK NORTH WINDS 15 TO 20 MPH...TEMPERATURES HAVE FALLEN OFF INTO
THE 60S NORTH OF INTERSTATE 20 WHICH HAS BROUGHT A TRUE AUTUMN
FEEL TO THOSE AREAS.
THE COLD FRONT SHOULD CLEAR THE CENTRAL TEXAS COUNTIES DURING THE
EVENING HOURS WITH A FEW LINGERING LIGHT SHOWERS OR SPRINKLES
CONTINUING OVERNIGHT. SATURATION WILL CONTINUE TO OCCUR ON THE
SHALLOW FRONTAL INVERSION AND PLENTIFUL STRATUS...SO WE WILL
CONTINUE TO UNDERCUT MOS HIGH TEMPERATURES BY A FEW DEGREES ON
SATURDAY. THE BROAD SURFACE RIDGE EXTENDING FROM THE GREAT LAKES
TO TEXAS WILL SHIFT EAST ON SUNDAY AND MONDAY. LIGHT SOUTHEAST
WINDS AND WEAK LOW LEVEL WARM ADVECTION SHOULD ALLOW HIGHS TO
CREEP BACK UP INTO THE 80S DESPITE CONTINUE CLOUDINESS IN THE
AREA. IN ADDITION...LOW LEVEL MOISTURE WILL SLOWLY INCREASE ACROSS
THE AREA WITH SURFACE DEW POINTS RISING BACK INTO THE 60S. HAVE
TRIMMED SLIGHT CHANCES TO JUST THE FAR NORTHWEST AND RED RIVER
COUNTIES MONDAY WHERE WEAK WARM ADVECTION COULD GENERATE A FEW
SHOWERS AND STORMS.
ANOTHER...YET A MUCH WEAKER COLD FRONT WILL MOVE THROUGH OKLAHOMA
AND INTO NORTHWEST TEXAS MONDAY NIGHT...THEN INTO NORTH AND CENTRAL
TEXAS TUESDAY. THIS COLD FRONT WILL LIKELY STALL OR WASH OUT ACROSS
CENTRAL TEXAS AND NOT BRING MUCH COOLING TO THE AREA. WHAT IT WILL
DO IS ACT AS A FOCUS FOR SCATTERED SHOWERS AND THUNDERSTORMS TUESDAY
WITH A SHORTWAVE ALOFT MOVING SOUTHEAST ACROSS THE SOUTHERN PLAINS.
BOTH MECHANISMS ARE NOT EXPECTED TO BE VIGOROUS...THUS WIDESPREAD
AND SUBSTANTIAL RAINFALL IS NOT EXPECTED FROM THE EARLY WEEK
SYSTEM.
THE UPPER HIGH WEST OF THE AREA WILL EXPAND EAST OVER TEXAS THE
LATTER HALF OF NEXT WEEK. INCREASING SUBSIDENCE AND DRYING OF THE
UPPER ATMOSPHERIC COLUMN WILL ALLOW AFTERNOON HIGH TEMPERATURES
TO HEAT BACK UP TO AROUND 90 DEGREES.
05/
&&
.PRELIMINARY POINT TEMPS/POPS...
DALLAS-FT. WORTH, TX 58 73 65 83 71 / 20 10 10 10 10
WACO, TX 60 75 63 85 70 / 30 10 10 10 10
PARIS, TX 55 72 59 80 66 / 20 10 10 10 10
DENTON, TX 55 72 62 83 69 / 20 10 10 10 10
MCKINNEY, TX 56 73 60 82 68 / 20 10 10 10 10
DALLAS, TX 58 74 64 83 71 / 20 10 10 10 10
TERRELL, TX 57 73 62 82 68 / 20 10 10 10 10
CORSICANA, TX 61 75 64 85 69 / 30 10 10 10 10
TEMPLE, TX 60 73 62 85 70 / 50 10 10 10 10
MINERAL WELLS, TX 55 71 62 82 68 / 20 10 10 10 10
&&
.FWD WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
/75
AREA FORECAST DISCUSSION
NWS FORT WORTH TX
321 PM CDT THU SEP 11 2014
.DISCUSSION...
PLENTY OF CHALLENGES THIS FORECAST PACKAGE AS WE TRACK A SLOW-
MOVING FRONT NOW EXTENDING FROM A GATESVILLE...TO CORSICANA...TO
CANTON LINE. A BROKEN LINE OF SHOWERS AND THUNDERSTORMS CONTAINING
LOCALLY HEAVY RAINFALL HAS ERUPTED IN THE PAST 1-2 HOURS ALONG THE
BOUNDARY. IN ADDITION...LOCALIZED FLOODING ISSUES WILL NEED TO BE
MONITORED ALONG THE COLD FRONT WITH THIS BROKEN LINE OF STORMS
WITH RICH PRECIPITABLE WATER VALUES WELL ABOVE 2 INCHES AND HIGH
THETA-E AIR BETWEEN 700-850MB. ANY TRAINING ACTIVITY WILL LIKELY
CAUSE SOME LOCALIZED HYDROLOGIC PROBLEMS. WE WILL CARRY THE HIGHEST
RAIN CHANCES THIS EVENING ALONG AND AHEAD OF THE FRONT OR ACROSS
THE SOUTHEAST HALF OF THE REGION. THE BEST INSTABILITY AND FORCING
WITH THE COLD FRONT WILL MOST LIKELY DRIVE THIS ACTIVITY THROUGH
NIGHTFALL. IN ADDITION...WE HAVE ADDED HIGHER CHANCES ACROSS THE
FAR WESTERN COUNTIES FOR LATE EVENING. THE APPROACH OF A SUBTLE
DISTURBANCE OVER WEST TEXAS WILL LIKELY PROVIDE ENOUGH LIFT TO
SUSTAIN A FEW SHOWER OR STORMS ACROSS THE FAR WESTERN COUNTIES
AFTER SUNSET.
THE WEST TEXAS DISTURBANCE WILL CONTINUE TO MOVE OVER THE RED RIVER
AREA AND SOUTHERN OKLAHOMA TONIGHT. NORTHERN AREAS...ESPECIALLY
THOSE ALONG AND NORTH OF I-20 WILL BE UNDERNEATH THE RIGHT ENTRANCE
REGION OF A 60-70KT JET STREAK STREAMING OVER OKLAHOMA. AS WE HEAD
INTO FRIDAY MORNING...A STRONGER DISTURBANCE CURRENTLY OVER WYOMING
WILL ROTATE SOUTHEAST OVER THE KANSAS/NEBRASKA BORDER AND SHOULD
SHUNT THE JET STREAK A LITTLE FURTHER SOUTH. THE COMBINATION OF
THESE FEATURES WILL PROVIDE THE SYNOPTIC LIFT...WHILE NOCTURNAL
LOW LEVEL WARM ADVECTION OVERRIDES THE SHALLOW FRONTAL INVERSION.
WITH THE FOCUS SHIFTING BACK NORTH...WILL MAINTAIN LIKELY CHANCES
FOR RAINFALL WHICH AT TIMES COULD BE LOCALLY HEAVY...BUT NOT ENOUGH
ALONG WITH ANTECEDENT DRY SOIL CONDITIONS TO ISSUE ANY FLOOD WATCHES
AT THIS POINT. 500-700MB LAPSE RATES WILL BE HOVERING AROUND 6 DEG/KM
WITH BOTH RUC AND NAM12 BUFKIT SOUNDINGS INDICATING A DEEP...BUT
SKINNY LAYER OF CAPE. ALL TOLD...SHOWERS WILL BE LIKELY OVERNIGHT
TONIGHT INTO FRIDAY MORNING ACROSS THESE AREAS WITH EMBEDDED/ELEVATED
THUNDERSTORMS AT TIMES. RAIN CHANCES AFTER NIGHTFALL ACROSS CENTRAL
TEXAS SHOULD DIMINISH TO LOWER CHANCES THAN WHAT WILL BE SEEN
ACROSS THE NORTH. THERE WILL BE QUITE A VARIANCE ON HIGH TEMPERATURES
FROM NORTHWEST TO SOUTHEAST FRIDAY. HIGHS WILL ONLY PUSH TO AROUND
70 DEGREES ACROSS THE FAR NORTHWEST... TO THE LOWER 90S ACROSS THE
FAR SOUTHEAST.
BETTER RAIN CHANCES SHIFT BACK OVER CENTRAL TEXAS ONCE AGAIN
FRIDAY AFTERNOON INTO SATURDAY MORNING. THE PASSAGE OF THE STRONG
SHORTWAVE TO THE NORTH TOWARD NORTHERN MISSOURI AND IOWA WILL HELP
SEND A STRONGER AND DEEPER PUSH OF COOLER AIR INTO THE NORTHERN
COUNTIES WITH THE SOUTH REMAINING WARMER AND MORE UNSTABLE. THE
UPPER HIGH WILL STRENGTHEN SOME BACK OVER THE AREA THIS WEEKEND
WITH JUST LINGERING LOW RAIN CHANCES ACROSS CENTRAL TEXAS WHERE
DEEPER MOISTURE WILL LINGER. THESE CHANCES SHOULD END BY NIGHTFALL
SATURDAY EVENING AS THE ATMOSPHERE STABILIZES. EVEN SO...CLOUD
COVER ON AND ABOVE THE DEEPENING FRONTAL INVERSION WILL MAINTAIN
CONSIDERABLE CLOUDINESS ACROSS THE REGION. THE CLOUDS COMBINED
WITH THE COOLER AIRMASS WILL HOLD HIGHS BETWEEN 75 AND 85 DEGREES
SATURDAY THAT WILL SLOWLY MODIFY TO THE 80S ON SUNDAY.
THE FORECAST AFTER THE WEEKEND BECOMES CHALLENGING ONCE AGAIN AS
WE MONITOR AN UPPER DISTURBANCE ROTATING AROUND THE WESTERN PERIPHERY
OF THE UPPER HIGH OVER THE WESTERN GULF COAST ON MONDAY. BY MONDAY
NIGHT AND TUESDAY...ANOTHER STRONG DISTURBANCE WILL MOVE DOWN
WITHIN NORTHWEST FLOW ALOFT ACROSS THE CENTRAL PLAINS AND DRAG A
SECOND COLD FRONT INTO SOUTHERN PLAINS BY TUESDAY. MOISTURE WILL
BE PLENTIFUL ENOUGH THAT WE HAVE MAINTAINED THE LOW CHANCES FOR
SHOWERS AND STORMS UNTIL TIMING AND ENVIRONMENTAL DETAILS BECOME
CLEARER FOR THAT TIME FRAME AND WE CAN DIAGNOSE WHEN THE BEST
CHANCES WILL OCCUR. THE LATTER HALF OF NEXT WEEK WAS KEPT DRY AND
WARM FOR NOW...AS THE SECOND FRONT WASHES OUT OVER THE SOUTHERN
PART OF THE STATE. HOWEVER...LOW RAIN CHANCES MAY NEED TO BE
EXTENDED ACROSS OUR CENTRAL TEXAS COUNTIES IF THE FRONT STALLS
FURTHER NORTH. HIGH TEMPERATURES WILL MODIFY BACK TO THE MID AND
UPPER 80S WITH A FEW READINGS IN THE LOWER 90S POSSIBLE ACROSS OUR
CENTRAL TEXAS COUNTIES.
05/
&&
.AVIATION...
/ISSUED 214 PM CDT THU SEP 11 2014/
FOR THE 18Z TAFS...PRECIPITATION CHANCES AND TIMING FLIGHT
CATEGORY RESTRICTIONS THIS AFTERNOON AND TONIGHT ARE THE PRIMARY
FORECAST CONCERNS.
FOR THIS AFTERNOON...A COLD FRONT WAS LOCATED JUST TO THE
SOUTHEAST OF WACO...MOVING SLOWLY TO THE SOUTHEAST. NUMEROUS
SHOWERS AND THUNDERSTORMS WERE DEVELOPING ALONG THIS FRONT AS OF
18Z...AND WILL LIKELY CONTINUE TO DO SO THROUGH THE REMAINDER OF
THE AFTERNOON. WENT AHEAD WITH VCTS FROM 18 TO 00Z AT THE WACO TAF
AS A RESULT. FOR THE DFW AREA...THERE WERE SOME SCATTERED SHOWERS
AND THUNDERSTORMS DEVELOPING ACROSS SOUTHEASTERN COLLIN
COUNTY...BUT THESE WERE ELEVATED IN NATURE WELL BEHIND THE FRONT.
SOME OF THIS ELEVATED ACTIVITY MAY BUILD WEST TOWARDS DFW/GKY/DAL
THROUGH THE PEAK HEATING HRS OF THE DAY...SO WENT AHEAD WITH A
MENTION OF VCSH IN THE TAFS THRU 21Z AS A RESULT. WILL AMEND THE
TAFS IF IT LOOKS LIKE THUNDERSTORM ACTIVITY IS GOING TO GET
CLOSER TO THE DFW TAFS THIS AFTERNOON. HIGH MVFR CIGS WILL HANG
AROUND THE DFW AREA THROUGH 21Z...BECOMING LOW VFR THEREAFTER.
THIS EVENING...RAIN SHOWER AND THUNDERSTORM ACTIVITY IS EXPECTED
TO DISSIPATE WITH THE LOSS OF DAYTIME HEATING ACROSS THE REGION.
CIGS SHOULD REMAIN VFR THROUGH MIDNIGHT. MODELS INDICATE THAT LOW-
LEVEL WINDS WILL BECOME SOUTHERLY OVER THE SHALLOW COLD FRONT THIS
EVENING...SETTING UP THE ENVIRONMENT FOR BETTER PRECIPITATION
CHANCES ACROSS THE DFW AREA AFTER MIDNIGHT.
LATE TONIGHT THRU TOMORROW MORNING...ELEVATED SHOWERS AND
THUNDERSTORMS ARE EXPECTED TO DEVELOP NORTH OF THE FRONT AFTER
MIDNIGHT. RAIN CHANCES LOOK BEST AT THE DFW AREA BETWEEN 10 AND
14Z WHEN MOST MODEL GUIDANCE MAXIMIZES LOW-LEVEL LIFT OVER THE
METROPLEX. HAVE VCSH FOR A FEW HOURS ON EITHER SIDE OF THIS
WINDOW...WITH VCTS AND PERSISTENT SHOWERS IN THE 10-14Z TIME FRAME
TO ACCOUNT FOR THIS LIFT. SHOWERS AND THUNDERSTORMS SHOULD
DISSIPATE ACROSS THE DFW AREA DURING THE LATE MORNING HOURS AS
SUBSIDENCE WORKS OVER THE AREA BEHIND THE FRONT.
THE ONLY HAZARDS EXPECTED FROM THUNDERSTORM ACTIVITY ARE CLOUD TO
GROUND LIGHTNING...AND REDUCED VISIBILITY FROM HEAVY RAINFALL.
CAVANAUGH
&&
.PRELIMINARY POINT TEMPS/POPS...
DALLAS-FT. WORTH, TX 73 75 62 77 66 / 70 70 20 10 10
WACO, TX 73 84 65 79 65 / 40 50 40 30 10
PARIS, TX 71 73 60 75 62 / 70 70 20 10 10
DENTON, TX 70 72 61 77 64 / 70 70 20 10 10
MCKINNEY, TX 70 72 59 75 63 / 70 70 20 10 10
DALLAS, TX 73 76 62 76 67 / 60 70 20 10 10
TERRELL, TX 73 79 63 76 64 / 60 70 30 10 10
CORSICANA, TX 74 83 65 79 65 / 50 50 40 20 10
TEMPLE, TX 72 86 65 78 65 / 30 60 50 30 20
MINERAL WELLS, TX 69 72 59 75 63 / 70 70 20 10 10
&&
.FWD WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
/05
AREA FORECAST DISCUSSION
NWS HOUSTON/GALVESTON TX
958 AM CDT THU SEP 11 2014
.UPDATE...
SEE DISCUSSION FOR MORNING UPDATE.
&&
.DISCUSSION...
NOT MANY CHANGES TO THIS MORNINGS FORECAST. WATER VAPOR CLEARLY
SHOWS TROPICAL WAVE MARCHING WEST THIS MORNING. SURFACE COLD FRONT IS
CURRENTLY RIGHT ON THE DALLAS/ FORT WORTH DOOR STEP. A LINE OF
SHOWERS AND THUNDERSTORMS HAS FORMED JUST AHEAD OF THE FRONT. FOR
SOUTHEAST TEXAS THE FRONT WILL REMAIN NORTH OF THE AREA THIS
AFTERNOON UNTIL THE SHORTWAVE IN MONTANA CAN PUSH FARTHER SOUTH
THIS EVENING. MOISTURE VALUES REMAIN NEAR AVERAGE FOR THE AREA
WITH CONVECTIVE TEMPERATURES IN THE UPPER 80S. HIGH RES MODELS
SHOWING SOME SHOWERS AND THUNDERSTORMS FORMING ALONG A SEA BREEZE
THIS AFTERNOON. CURRENT FORECAST HAS THIS COVERED. ONLY MADE MINOR
TWEAKS TO ACCOUNT FOR TRENDS. 23
&&
.PREV DISCUSSION... /ISSUED 358 AM CDT THU SEP 11 2014/
DISCUSSION...
SURFACE COLD FRONT MADE SOME MORE PROGRESS EARLIER TONIGHT BEFORE
LOOSING STEAM OVER THE LAST COUPLE OF HOURS. AS OF CURRENT THE
FRONT WAS LOCATED JUST NORTH OF THE DALLAS/ FORT WORTH AREA. A 0Z
500 MB HAND ANALYSIS REVEALED A POTENT SHORTWAVE DIVING SOUTH
OVER MONTANA. AT 250MB RIDGING HAS STARTED TO FLATTEN AS A TROUGH
AXIS PUSHES IN FROM THE WEST. FOR TODAY MODELS ARE SHOWING A BIT
MORE COVERAGE THAN PREVIOUSLY ADVERTISED. CURRENT PWAT VALUES...
COURTESY OF GPS MET SITE... ARE AROUND 1.60". GFS FORECAST
SOUNDINGS FOR THIS AFTERNOON SHOW PWAT VALUES AROUND 1.7" WITH K
INDEX VALUES NEAR 30 WHILE THE NAM IS SLIGHTLY MORE AGGRESSIVE.
THE RIDGE SHOULD CONTINUE TO FLATTEN THIS AFTERNOON SO WILL LEAN
TO THE SLIGHTLY MORE AGGRESSIVE NAM. HIGH RES MODELS ALSO SUPPORT
THIS WITH CHANCE COVERAGE ALONG THE COAST. THE FRONT SHOULD REMAIN
NORTH OF THE AREA THIS AFTERNOON BUT THE RAP IS DEVELOPING PRECIP
ALONG THE FRONT AND PUSHING IT INTO OUR NORTHERN ZONES THIS AFTERNOON.
THIS EVENING INTO FRIDAY SOME CONVECTION COULD MAKE IT INTO OUR
NORTHERN ZONES BEFORE DISSIPATING. FRIDAY MORNING A TROPICAL WAVE
CURRENTLY LOCATED NEAR FLORIDA WILL APPROACH THE MEXICAN COAST
LINE. AS THE TROPICAL WAVE MOVES WEST IT WILL BRING VERY MOIST AIR
WITH IT. PWATS SURGE TOWARDS 2.20" FRIDAY AFTERNOON INTO SATURDAY.
AT THE SAME TIME THE FRONT CURRENTLY NORTH OF DALLAS/ FORT WORTH
WILL FINALLY MOVE INTO THE AREA. UPPER LEVEL SUPPORT FOR THIS
SYSTEM IS WEAK THOUGH. THE SHORTWAVE CURRENTLY DIVING SOUTH IN
MONTANA WILL QUICKLY START TO PULL TO THE EAST FRIDAY WHICH WILL
HELP TO STALL AND WASH OUT THE FRONT OVER OUR AREA FRIDAY EVENING
INTO SATURDAY MORNING. RAIN CHANCES WILL QUICKLY START TO RISE
FRIDAY AS THE WAVE APPROACHES. LIFT WILL COME FROM THE SURFACE
BOUNDARY AND SPEED CONVERGENCE AT 850MB. GIVEN VERY HIGH MOISTURE
VALUES AND LIFT RAIN LOOKS LIKELY FRIDAY EVENING INTO SATURDAY.
OMEGA VALUES FROM BOTH THE GFS AND NAM ALSO SUPPORT THIS. AS OF
CURRENT IT LOOKS THAT RAIN WILL START FRIDAY MORNING OVER THE
WATERS (IN ASSOCIATION WITH THE APPROACHING TROPICAL WAVE) AND
JUST NORTH OF THE AREA (IN ASSOCIATION WITH THE FRONT). RAIN WILL
THEN MOVE INLAND ALONG A SEA BREEZE AND POSSIBLY COLLIDE WITH ON
GOING SHOWERS AND THUNDERSTORMS WITH THE SURFACE FRONT TO THE
NORTH. THE EXACT LOCATION OF THE FRONT AND EXTENT OF PRECIPITATION
OVER THE WATERS COULD GREATLY INFLUENCE THE EVENTUAL DISTRIBUTION
OF RAINFALL. WITH THE WEAK STEERING FLOW THE CHANCE FOR HEAVY
RAIN REMAINS POSSIBLE FRIDAY AFTERNOON INTO SATURDAY MORNING.
ABOVE AVERAGE MOISTURE VALUES ARE EXPECTED TO REMAIN OVER THE AREA
THROUGH THE WEEKEND ALLOWING THE CHANCE OF RAIN TO CONTINUE.
MODELS DUE STRUGGLE ON HOW TO HANDLE THE REMNANT ENERGY OF THE
WAVE THOUGH AS IT MOVES INTO MEXICO. IN GENERAL MODELS MOVE THE
ENERGY NORTH AROUND A WEAK UPPER LEVEL RIDGE AND PICK IT BACK UP
IN THE FLOW. THE NAM MOVES PIECES OF POSITIVE VORTICITY OVER OUR
AREA SATURDAY EVENING WHILE THE GFS KEEPS THE ENERGY WEST OF US.
WHERE THIS LEFTOVER ENERGY MOVES NORTH WILL AFFECT WHERE THE
GREATEST CHANCES OF RAIN WILL BE SATURDAY INTO SUNDAY. BY NEXT
WEEK THE UPPER LEVEL FLOW WILL AMPLIFY A BIT OVER THE EASTERN
UNITED STATES ALLOWING MID LEVEL WINDS TO TURN FROM THE NORTHWEST
OVER SOUTHEAST TEXAS. THIS WILL ALSO ALLOW UPPER LEVEL
DISTURBANCES TO MOVE OVER THE AREA. THE BEST CHANCES OF RAIN WILL
BE IN THE AFTERNOON OF EACH DAY NEXT WEEK THANKS TO DAY TIME
HEATING. HAVE TRENDED POPS UP IN THE AFTERNOON FOR NEXT WEEK TO
ACCOUNT FOR THIS. 23
MARINE...
TYPICAL SUMMER LIKE PATTERN TODAY WITH ISO/SCT PRECIP IN COASTAL
WATERS IN THE MORNING HOURS, LIGHT-MODERATE SE WINDS AND LOW SEAS.
ERLY WAVE IN THE GULF WILL TRANSPORT INCREASED MOISTURE LEVELS INTO
THE WATERS LATER TONIGHT LEADING TO MORE AREAL PRECIP COVERAGE FRI
MORNING. AS THE WAVE APPROACHES THE WESTERN GULF COASTLINE FRI NIGHT
& SATURDAY...LOOK FOR WINDS TO INCREASE, BECOME MORE ERLY AND SEAS
TO BUILD. MAY NEED CAUTION FLAGS DURING THIS TIME. MODERATE ENE FLOW
AND RAIN CHANCES SHOULD PERSIST THRU THE WEEKEND AS GRADIENT
TIGHTENS NEAR THE COAST COMPLIMENTS OF A FRONTAL BOUNDARY LINGERING
IN THE REGION. 47
AVIATION...
HIGHER MOISTURE LEVELS HUGGING THE COAST WILL LEAD TO ISO/SCT PRECIP THERE
AND IN THE COASTAL COUNTIES THRU LATE MORNING. IT SHOULD CREEP INLAND TODAY
WITH DAYTIME HEATING AND EXPAND INTO METRO TAF SITES FROM LATE MORNING-LATE
AFTN. INCLUDED SOME VCSH`S FOR NOW. FRONTAL BOUNDARY MOVING INTO N TX SHOULD
PROVIDE A FOCUS FOR SOME TSRA LATER TODAY BUT SUSPECT MOST WILL REMAIN N OF CLL
THRU THE TAF PERIOD SO NO MENTION THERE YET. DO ANTICIPATE A DEEPER SURGE OF
MOISTURE TO MOVE INTO THE COASTAL WATERS PRIOR TO SUNRISE FRI AND EXPECT FAIRLY
GOOD CHANCES OF PRECIP S OF I-10 BETWEEN 10-18Z FRI...FOLLOWED BY MORE COVERAGE
FRI AFTN (BEYOND 12Z TAF). OUTSIDE OF PRECIP MAINLY VFR CONDITIONS SHOULD
PREVAIL. 47
&&
.PRELIMINARY POINT TEMPS/POPS...
COLLEGE STATION (CLL) 97 75 90 71 84 / 20 30 60 60 40
HOUSTON (IAH) 96 77 91 73 86 / 30 30 60 60 50
GALVESTON (GLS) 91 82 90 79 86 / 20 30 60 60 60
&&
.HGX WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
GM...NONE.
&&
$$
DISCUSSION...23
AREA FORECAST DISCUSSION
NWS HOUSTON/GALVESTON TX
358 AM CDT THU SEP 11 2014
.DISCUSSION...
SURFACE COLD FRONT MADE SOME MORE PROGRESS EARLIER TONIGHT BEFORE
LOOSING STEAM OVER THE LAST COUPLE OF HOURS. AS OF CURRENT THE
FRONT WAS LOCATED JUST NORTH OF THE DALLAS/ FORT WORTH AREA. A 0Z
500 MB HAND ANALYSIS REVEALED A POTENT SHORTWAVE DIVING SOUTH
OVER MONTANA. AT 250MB RIDGING HAS STARTED TO FLATTEN AS A TROUGH
AXIS PUSHES IN FROM THE WEST. FOR TODAY MODELS ARE SHOWING A BIT
MORE COVERAGE THAN PREVIOUSLY ADVERTISED. CURRENT PWAT VALUES...
COURTESY OF GPS MET SITE... ARE AROUND 1.60". GFS FORECAST
SOUNDINGS FOR THIS AFTERNOON SHOW PWAT VALUES AROUND 1.7" WITH K
INDEX VALUES NEAR 30 WHILE THE NAM IS SLIGHTLY MORE AGGRESSIVE.
THE RIDGE SHOULD CONTINUE TO FLATTEN THIS AFTERNOON SO WILL LEAN
TO THE SLIGHTLY MORE AGGRESSIVE NAM. HIGH RES MODELS ALSO SUPPORT
THIS WITH CHANCE COVERAGE ALONG THE COAST. THE FRONT SHOULD REMAIN
NORTH OF THE AREA THIS AFTERNOON BUT THE RAP IS DEVELOPING PRECIP
ALONG THE FRONT AND PUSHING IT INTO OUR NORTHERN ZONES THIS AFTERNOON.
THIS EVENING INTO FRIDAY SOME CONVECTION COULD MAKE IT INTO OUR
NORTHERN ZONES BEFORE DISSIPATING. FRIDAY MORNING A TROPICAL WAVE
CURRENTLY LOCATED NEAR FLORIDA WILL APPROACH THE MEXICAN COAST
LINE. AS THE TROPICAL WAVE MOVES WEST IT WILL BRING VERY MOIST AIR
WITH IT. PWATS SURGE TOWARDS 2.20" FRIDAY AFTERNOON INTO SATURDAY.
AT THE SAME TIME THE FRONT CURRENTLY NORTH OF DALLAS/ FORT WORTH
WILL FINALLY MOVE INTO THE AREA. UPPER LEVEL SUPPORT FOR THIS
SYSTEM IS WEAK THOUGH. THE SHORTWAVE CURRENTLY DIVING SOUTH IN
MONTANA WILL QUICKLY START TO PULL TO THE EAST FRIDAY WHICH WILL
HELP TO STALL AND WASH OUT THE FRONT OVER OUR AREA FRIDAY EVENING
INTO SATURDAY MORNING. RAIN CHANCES WILL QUICKLY START TO RISE
FRIDAY AS THE WAVE APPROACHES. LIFT WILL COME FROM THE SURFACE
BOUNDARY AND SPEED CONVERGENCE AT 850MB. GIVEN VERY HIGH MOISTURE
VALUES AND LIFT RAIN LOOKS LIKELY FRIDAY EVENING INTO SATURDAY.
OMEGA VALUES FROM BOTH THE GFS AND NAM ALSO SUPPORT THIS. AS OF
CURRENT IT LOOKS THAT RAIN WILL START FRIDAY MORNING OVER THE
WATERS (IN ASSOCIATION WITH THE APPROACHING TROPICAL WAVE) AND
JUST NORTH OF THE AREA (IN ASSOCIATION WITH THE FRONT). RAIN WILL
THEN MOVE INLAND ALONG A SEA BREEZE AND POSSIBLY COLLIDE WITH ON
GOING SHOWERS AND THUNDERSTORMS WITH THE SURFACE FRONT TO THE
NORTH. THE EXACT LOCATION OF THE FRONT AND EXTENT OF PRECIPITATION
OVER THE WATERS COULD GREATLY INFLUENCE THE EVENTUAL DISTRIBUTION
OF RAINFALL. WITH THE WEAK STEERING FLOW THE CHANCE FOR HEAVY
RAIN REMAINS POSSIBLE FRIDAY AFTERNOON INTO SATURDAY MORNING.
ABOVE AVERAGE MOISTURE VALUES ARE EXPECTED TO REMAIN OVER THE AREA
THROUGH THE WEEKEND ALLOWING THE CHANCE OF RAIN TO CONTINUE.
MODELS DUE STRUGGLE ON HOW TO HANDLE THE REMNANT ENERGY OF THE
WAVE THOUGH AS IT MOVES INTO MEXICO. IN GENERAL MODELS MOVE THE
ENERGY NORTH AROUND A WEAK UPPER LEVEL RIDGE AND PICK IT BACK UP
IN THE FLOW. THE NAM MOVES PIECES OF POSITIVE VORTICITY OVER OUR
AREA SATURDAY EVENING WHILE THE GFS KEEPS THE ENERGY WEST OF US.
WHERE THIS LEFTOVER ENERGY MOVES NORTH WILL AFFECT WHERE THE
GREATEST CHANCES OF RAIN WILL BE SATURDAY INTO SUNDAY. BY NEXT
WEEK THE UPPER LEVEL FLOW WILL AMPLIFY A BIT OVER THE EASTERN
UNITED STATES ALLOWING MID LEVEL WINDS TO TURN FROM THE NORTHWEST
OVER SOUTHEAST TEXAS. THIS WILL ALSO ALLOW UPPER LEVEL
DISTURBANCES TO MOVE OVER THE AREA. THE BEST CHANCES OF RAIN WILL
BE IN THE AFTERNOON OF EACH DAY NEXT WEEK THANKS TO DAY TIME
HEATING. HAVE TRENDED POPS UP IN THE AFTERNOON FOR NEXT WEEK TO
ACCOUNT FOR THIS. 23
&&
.MARINE...
TYPICAL SUMMER LIKE PATTERN TODAY WITH ISO/SCT PRECIP IN COASTAL
WATERS IN THE MORNING HOURS, LIGHT-MODERATE SE WINDS AND LOW SEAS.
ERLY WAVE IN THE GULF WILL TRANSPORT INCREASED MOISTURE LEVELS INTO
THE WATERS LATER TONIGHT LEADING TO MORE AREAL PRECIP COVERAGE FRI
MORNING. AS THE WAVE APPROACHES THE WESTERN GULF COASTLINE FRI NIGHT
& SATURDAY...LOOK FOR WINDS TO INCREASE, BECOME MORE ERLY AND SEAS
TO BUILD. MAY NEED CAUTION FLAGS DURING THIS TIME. MODERATE ENE FLOW
AND RAIN CHANCES SHOULD PERSIST THRU THE WEEKEND AS GRADIENT
TIGHTENS NEAR THE COAST COMPLIMENTS OF A FRONTAL BOUNDARY LINGERING
IN THE REGION. 47
&&
.AVIATION...
HIGHER MOISTURE LEVELS HUGGING THE COAST WILL LEAD TO ISO/SCT PRECIP THERE
AND IN THE COASTAL COUNTIES THRU LATE MORNING. IT SHOULD CREEP INLAND TODAY
WITH DAYTIME HEATING AND EXPAND INTO METRO TAF SITES FROM LATE MORNING-LATE
AFTN. INCLUDED SOME VCSH`S FOR NOW. FRONTAL BOUNDARY MOVING INTO N TX SHOULD
PROVIDE A FOCUS FOR SOME TSRA LATER TODAY BUT SUSPECT MOST WILL REMAIN N OF CLL
THRU THE TAF PERIOD SO NO MENTION THERE YET. DO ANTICIPATE A DEEPER SURGE OF
MOISTURE TO MOVE INTO THE COASTAL WATERS PRIOR TO SUNRISE FRI AND EXPECT FAIRLY
GOOD CHANCES OF PRECIP S OF I-10 BETWEEN 10-18Z FRI...FOLLOWED BY MORE COVERAGE
FRI AFTN (BEYOND 12Z TAF). OUTSIDE OF PRECIP MAINLY VFR CONDITIONS SHOULD
PREVAIL. 47
&&
.PRELIMINARY POINT TEMPS/POPS...
COLLEGE STATION (CLL) 97 75 90 71 85 / 20 30 60 60 40
HOUSTON (IAH) 95 77 91 73 86 / 30 30 60 60 50
GALVESTON (GLS) 91 82 90 79 86 / 20 30 60 60 60
&&
.HGX WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
GM...NONE.
&&
$$
DISCUSSION...23
AVIATION/MARINE...47
AREA FORECAST DISCUSSION
NWS HOUSTON/GALVESTON TX
1150 PM CDT WED SEP 10 2014
.DISCUSSION...
SEE THE 06Z AVIATION DISCUSSION BELOW.
40
&&
.AVIATION...
A COUPLE OF ITEMS TO COVER FOR THIS FORECAST PERIOD. THE FIRST
WILL BE THE POSSIBILITY FOR MVFR CONDITIONS TONIGHT THROUGH 14Z
THURSDAY MORNING. BEST CHANCES APPEAR TO BE AT KCLL...KUTS...AND
KCXO. THE LATEST NAM12 SHOWED A LOW-LEVEL JET OVERHEAD OF KCLL
WHICH SHOULD TRANSLATE TO A LOW CLOUD DECK FORMING BETWEEN 08Z AND
10Z AT THE THREE SITES.
THE SECOND ITEM REGARDS RAIN CHANCES. DECENT MOISTURE ADVECTION
WAS HELPING FORM ISOLATED SHOWERS IN THE GULF AT 0430Z. THE HIGH
RESOLUTION AND NAM12 MODELS ALL INDICATE THESE MAY WORK THEIR WAY
INTO KGLS AFTER 09Z. THE NAM12 WEAKENS THE SURFACE PRESSURE
GRADIENT AS IT BUILDS A HIGH PRESSURE RIDGE INTO THE COASTAL AREAS
FROM THE EAST. HOWEVER...THE MOISTURE INCREASES DURING THE
AFTERNOON PERIOD WITH PW/S REACHING TO BETWEEN 1.9 AND 2.2 INCHES.
WITH THIS IN MIND...FELT THERE WAS A DECENT CHANCE FOR ISOLATED
SHOWERS TO AFFECT THE INLAND SITES DURING THE AFTERNOON FROM KLBX
TO KCXO. FOR NOW WILL GO WITH A VICINITY MENTION.
LASTLY...DECENT RAIN CHANCES ARE LOOKING TO OCCUR WITH THE ADVANCE
OF A COLD FRONT INTO SE TX ON FRIDAY. THE FORECAST COVERAGE AND
TIMING BY THE MODELS IS TOO BROAD AT THIS TIME TO PINPOINT FOR
THE AVIATION SITES. FOR NOW THE BEST CHANCES LOOK TO BEGIN FROM
HOUSTON TO THE COAST SOMETIME LATE MORNING ON FRIDAY.
40
&&
.PREV DISCUSSION... /ISSUED 952 PM CDT WED SEP 10 2014/
UPDATE...
SEE EVENING UPDATE.
DISCUSSION...
AT 8 PM...A COLD FRONT EXTENDED FROM FT SMITH TO NEAR SHERMAN TO
BIG SPRINGS. AT 850 MB...A TROUGH OF LOW PRESSURE EXTENDED NORTH
TO SOUTH ACROSS WEST TEXAS WITH DEEP 850 MOISTURE OVER OK...AR
AND NE TX. ANOTHER WEAK TROUGH WAS NOTED BETWEEN OKC AND DFW. 850
TEMPS WERE -3 C AT GLASGOW MT WHICH IS PRETTY COOL FOR THIS TIME
OF YEAR. A POOL OF DEEPER 700 MB MOISTURE WAS LOCATED OVER N TX
AND S OK WITH A WEAK TROUGH OVER SW TX. AT 250 MB...A BROAD TROUGH
WAS LOCATED OVER THE CENTRAL PLAINS WITH UPPER LEVEL RIDGING
EXTENDING FROM THE SOUTHERN APPALACHIANS ACROSS COASTAL TEXAS.
00Z MODEL RUNS ARE JUST COMING IN BUT SHORT TERM GUIDANCE IS
TRENDING WETTER FOR THURSDAY. THE RAP IN PARTICULAR BRINGS IN
SLIGHTLY HIGHER MOISTURE EARLY THURSDAY MORNING COURTESY OF A
BROAD EASTERLY WAVE THAT EXTENDS FROM THE MS COAST TO THE MEXICAN
COAST. 00Z SOUNDINGS CAME IN DRY AND GPS MET NETWORK SHOWS PW
VALUES AROUND 1.6 INCHES WHICH IS ON THE DRY SIDE FOR EARLY SEPT.
YET THE RAP AND TO A LESSER EXTENT THE HRRR...ARW AND TEXAS TECH
WRF SHOW SHRA/TSRA DEVELOPING BY 13Z AND SPREADING INLAND. THE RAP
ALSO BRINGS A WIND SHIFT TO THE COLLEGE STATION AREA AROUND 18Z.
PRESSURE RISES BEHIND THE FRONT ARE NOT THAT IMPRESSIVE SO PREFER
THE NAM 12 FOR FRONTAL TIMING. ADDED POPS FOR LATE TONIGHT ALONG
THE COAST AND ADDED MORNING POPS FOR AREAS SOUTH OF I-10. NEW
ZONES OUT BY 10 PM. 43
CLIMATE...
CRUNCHING SOME NUMBERS TONIGHT ON RAINFALL DEFICITS ACROSS THE
AREA. GALVESTON IS OVER 75 INCHES BELOW NORMAL SINCE JAN 1 2009.
HOBBY AIRPORT IS NOT THAT FAR BEHIND AND IS 65 INCHES BELOW NORMAL
SINCE 2009. HOPEFULLY RAIN THIS WEEKEND WILL PUT A DENT INTO SOME
THESE NUMBERS.
HURRICANE CARLA MADE LANDFALL ON SEPT 11 1961. IT`S THE LAST CAT 4
TO AFFECT THE UPPER TEXAS COAST. CARLA WAS BRIEFLY A CAT 5 OVER
THE GULF. 43
&&
.PRELIMINARY POINT TEMPS/POPS...
COLLEGE STATION (CLL) 77 97 75 90 71 / 10 20 30 60 60
HOUSTON (IAH) 77 96 77 91 74 / 10 20 30 60 60
GALVESTON (GLS) 83 91 82 90 79 / 20 20 30 60 60
&&
.HGX WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
GM...NONE.
&&
$$
DISCUSSION...43
AVIATION/MARINE...40
FOR FREQUENTLY ASKED QUESTIONS ABOUT THE AREA FORECAST DISCUSSION
VISIT...
HTTP://WEATHER.GOV/SALTLAKECITY/GENERAL/AFD_FAQS.PHP (ALL LOWER CASE)
FORECAST DISCUSSION FOR ROUTINE AFTERNOON FORECAST ISSUANCE
.SHORT TERM...TONIGHT AND FRIDAY
ISSUED AT 254 PM CDT THU SEP 11 2014
THE LATEST RAP ANALYSIS AND SATELLITE/RADAR IMAGERY SHOW A 1037MB
CANADIAN HIGH PRESSURE SYSTEM BUILDING SOUTHEAST ACROSS THE NORTHERN
PLAINS AND MISSISSIPPI VALLEY. THE COMBO OF NORTHERLY FLOW OFF LAKE
SUPERIOR AND DIURNAL HEATING HAS MAINTAINED THE BROKEN TO OVERCAST
CONDITIONS ACROSS THE REGION. CLOUDS ARE LOOKING MORE CELLULAR OVER
N-C WISCONSIN INDICATING A DIURNAL COMPONENT TO THE CLOUD MASS.
SCATTERED SHOWERS ARE OCCURRING OVER NORTHEAST MINNESOTA AND
NORTHWEST WISCONSIN...WITH HELP FROM A WEAK SHORTWAVE OVER THAT
REGION. THIS WAVE IS LIFTING OFF TO THE NORTHEAST...SO DO NOT THINK
THE SHOWER ACTIVITY WILL REACH INTO N-C WISCONSIN THIS AFTERNOON.
THE NEXT SHORTWAVE IS DIVING SOUTHEAST OVER SOUTHERN MONTANA AND
WILL MOVE EAST TOWARDS THE REGION TOMORROW. THE MAIN CONCERNS ARE
FROST POTENTIAL TONIGHT AND LIGHT RAIN CHANCES TOMORROW.
TONIGHT...CANADIAN HIGH PRESSURE WILL BUILD TOWARDS THE REGION AS A
POTENT SHORTWAVE MOVES ACROSS THE NORTHERN PLAINS. AS SURFACE
PRESSURE RISES...LOW LEVEL FLOW WILL BECOME BROADLY
ANTICYCLONIC...WHICH WILL PROMOTE BREAKING UP OF THE LOW STRATUS.
HOWEVER...EVEN THOUGH THE FLOW WILL BECOME LIGHT...TRAJECTORIES ARE
ONSHORE OFF LAKE SUPERIOR WHERE DELTA T/S ARE SUFFICIENT FOR LAKE
CLOUDS. ADDITIONALLY...THERE IS REALLY NO SOURCE OF DRY AIR TO
BE FOUND ACROSS THE REGION. EVEN THOUGH CLOUDS OVER THE WESTERN
PART OF THE STATE APPEAR TO HAVE A DIURNAL LOOK TO THEM...CLOUDS
ORIGINATING OFF LAKE SUPERIOR COULD BECOME TRAPPED BENEATH THE
NOCTURNAL INVERSION. FURTHERMORE...MID AND HIGH CLOUDS WILL BE
INCREASING AFTER MIDNIGHT AHEAD OF THE SHORTWAVE OVER THE PLAINS.
ALL OF THIS MAKES FOR A LOW CONFIDENCE CLOUD/TEMP/FROST FORECAST.
BECAUSE WE ARE ALREADY OFF TO A COLD START...ANY AMOUNT OF CLEARING
WILL CAUSE TEMPS TO FALL QUICKLY OVER N-C WISCONSIN. MET/MAV/MEX
GUIDANCE ALL SHOW LOW TEMPS IN THE LOWER 30S OVER N-C WISCONSIN. WILL
ERROR ON THE SIDE OF CAUTION BECAUSE OF THIS POTENTIAL AND ISSUE A
FROST ADVISORY FOR N-C WISCONSIN. THE REST OF THE AREA SHOULD SEE
TEMPS IN THE UPPER 30S TO MIDDLE 40S.
FRIDAY...THE POTENT SHORTWAVE WILL MOVE ACROSS THE NORTHERN
MISSISSIPPI VALLEY AND INTO WESTERN WISCONSIN. EVEN THOUGH QG
FORCING AHEAD OF THE WAVE LOOKS RATHER IMPRESSIVE...MOISTURE WILL
ONLY BE 60 TO 80 PCT OF NORMAL AND INSTABILITY IS RATHER POOR.
CHANCES FOR PRECIP WILL IMPROVE DURING THE AFTERNOON AS THE WAVE
APPROACHES AND UPPER DIVERGENCE INCREASES. MODELS ARE ALSO
INDICATING MID-LEVEL CONVERGENCE OVER NORTHEAST AND EAST-CENTRAL
WISCONSIN THAT COULD PROVIDE A FOCUS FOR A BAND OF LIGHT RAIN. WILL
INCREASE PRECIP CHANCE IN THIS AREA FOR THE AFTERNOON.
NORTH-CENTRAL WILL HAVE THE NEXT BEST CHANCE OF SEEING RAIN WHERE
THE DEFORMATION ZONE APPROACHES DURING THE AFTERNOON. SHOULD BE
ANOTHER CLOUDY AND COOL DAY WITH HIGHS IN THE LOW TO MID 50S.
.LONG TERM...FRIDAY NIGHT THROUGH THURSDAY
ISSUED AT 254 PM CDT THU SEP 11 2014
LIGHT RAIN SHOULD END IN EASTERN WISCONSIN FRIDAY EVENING
AS THE UPPER SYSTEM EXITS. IF THERE IS SUFFICIENT CLEARING THERE COULD
BE A FREEZE OR FROST IN NORTHCENTRAL WISCONSIN FRIDAY NIGHT.
SUNNY AND COOL WEATHER SATURDAY AS A SURFACE HIGH MOVES BY. CLOUDS WILL
INCREASE SUNDAY AS A WEAK FRONTAL SYSTEM APPROACHES FROM THE NORTHERN
PLAINS. NOT MUCH MOISTURE AVAILABLE SO ONLY EXPECT SCATTERED SHOWERS
SUNDAY NIGHT AND MONDAY WITH THE FRONTAL PASSAGE. THEN DRY AND SEASONABLE
FOR MUCH OF THE REMINDER OF NEXT WEEK WITH NORTHWEST FLOW ALOFT.
&&
.AVIATION...FOR 18Z TAF ISSUANCE
ISSUED AT 1153 AM CDT THU SEP 11 2014
WIDESPREAD BROKEN MVFR CIGS WILL PREVAIL FOR MUCH OF THE
AFTERNOON...THOUGH EXPECTING CIGS TO SLOWLY RISE...POSSIBLY TO VFR
BY 22-00Z. DIFFICULT TO ESTIMATE WHEN BKN CIGS WILL SCATTER DUE TO
NORTHERLY UNSTABLE FLOW OFF LAKE SUPERIOR CONTINUING THROUGH THE
NIGHT. THE BEST GUESS IS SOMETIME THIS EVENING WHEN THIS FLOW OFF
LAKE SUPERIOR LIGHTENS AND THE INVERSION WEAKENS. BUT IF THE
NOCTURNAL INVERSION DUE TO COOLING TRAPS THE RESIDUAL MOISTURE IN
THE BOUNDARY LAYER...THEN BKN CLOUDS COULD STICK AROUND FOR MUCH OF
THE NIGHT. IF CLOUDS DO SCATTER...THEN BKN CIGS WILL LIKELY DEVELOP
AGAIN BY MIDDAY TOMORROW AHEAD OF THE NEXT UPPER DISTURBANCE.
&&
.GRB WATCHES/WARNINGS/ADVISORIES...
FROST ADVISORY FROM MIDNIGHT TONIGHT TO 8 AM CDT FRIDAY FOR
WIZ005-010>012-018-019.
&&
$$
SHORT TERM.....MPC
LONG TERM......RDM
AVIATION.......MPC
AREA FORECAST DISCUSSION
NWS PUEBLO CO
1128 PM MDT FRI SEP 12 2014
.UPDATE...
ISSUED AT 549 PM MDT FRI SEP 12 2014
LOOKING AT SAT PIX...AND HI RES RH FIELDS IN THE LOWER LVLS OF THE
ATMOSPHERE AND PRGD SOUNDINGS...HAVE PLAYED UP MORE LOW CLOUDS FOR
TONIGHT THAN WERE IN EARLIER FCST PRODUCTS. FCST ARE BEING UPDATED
AS I WRITE.
&&
.SHORT TERM...(THIS EVENING THROUGH SATURDAY)
ISSUED AT 242 PM MDT FRI SEP 12 2014
WIDESPREAD LOW CLOUDS CONTINUE TO COVER THE SERN CO PLAINS THIS
AFTERNOON...WITH TEMPS IN THE 40S. THE REST OF THE FORECAST AREA
HAS HAD MOSTLY SUNNY SKIES...WITH SOME CONVECTIVE CLOUDS DEVELOPING
OVER THE SRN MTNS AND SAN LUIS VALLEY. THERE CONTINUES TO BE SOME
SPOTTY LIGHT DRIZZLE IN LOCATIONS NR THE ERN MTNS. THE NAM HAS WAY
OVERDONE THE PCPN OVR THE SERN PLAINS FOR TODAY...WITH THE HRRR
BEING MORE REASONABLE. FOR THIS EVENING AND OVERNIGHT THE NAM
PRINTS OUT SOME ISOLD PCPN OVR THE SRN CO MTNS. THE HRRR IS DRY FOR
THIS EVENING. IT IS POSSIBLE THAT A FEW SHOWERS COULD DEVELOP FOR
THE EVENING HOURS...BUT FOR NOW WL LEAVE SILENT POPS IN THE
FORECAST. THE NAM AND HRRR ARE STILL SHOWING A DECREASE IN LOW LEVEL
CLOUD COVER LATER THIS AFTERNOON AND EARLY THIS EVENING...BUT NOT
SEEING ANY EVIDENCE OF THIS IN THE SATELLITE IMAGES YET. BOTH MODELS
THEN SHOW THE POTENTIAL FOR LOW CLOUD REFORMING OVR PORTIONS OF THE
PLAINS BY LATE EVENING. OVERNIGHT LOW TEMPS ARE EXPECTED TO BE IN
THE UPPER 30S TO LOWER 40S OVR THE SERN PLAINS...THE COLDEST AREAS
LOOK TO BE NORTHERN PORTIONS OF PUEBLO COUNTY...EL PASO AND CROWLEY
COUNTIES. LOWS IN THESE LOCATIONS LOOK LIKE THEY WL BE IN THE LOWER
30S. HAVE DECIDED TO ISSUE A FROST ADVISORY FOR THESE COUNTIES JUST
IN CASE THERE ARE POCKETS OF FROST.
MODELS ARE INDICATING THAT THE LOW CLOUDS SHOULD DISSIPATE BY LATE
MORNING ON SATURDAY WITH A GOOD WARM UP IN STORE. HIGHS ON SAT OVR
THE SERN PLAINS SHOULD BE IN THE 70S...WITH MID TO UPPER 70S IN THE
SAN LUIS VALLEY. GENERALLY DRY WESTERLY FLOW ALOFT IS EXPECTED OVR
THE FORECAST AREA. THE NAM AGAIN PRINTS OUT SOME LIGHT PCPN OVR THE
SRN CO MTNS AND SAN LUIS VALLEY SAT AFTERNOON...SO WL LEAVE SOME
ISOLD POPS IN THE FORECAST FOR THE SW MTNS AND THE SANGRES.
.LONG TERM...(SATURDAY NIGHT THROUGH FRIDAY)
ISSUED AT 242 PM MDT FRI SEP 12 2014
MODELS IN GOOD AGREEMENT THROUGH THE EXTENDED PERIOD WITH SMALL
ENSEMBLE SPREADS AND HIGHER FORECAST CONFIDENCE.
SATURDAY NIGHT THROUGH SUNDAY NIGHT...FLAT ZONAL WESTERLY FLOW
WILL PERSIST ACROSS COLORADO THROUGH THIS PERIOD AS AN UPPER RIDGE
BEGINS TO BUILD ALONG THE WEST COAST AND SHORTWAVE TROUGH DROPS
SOUTH OUT OF CANADA INTO THE NORTHERN PLAINS. EXPECT ISOLATED
SHOWERS AND THUNDERSTORMS OVER THE MOUNTAINS ON SATURDAY EVENING
TO DISSIPATE AROUND SUNDOWN WITH LOSS OF DAYTIME INSTABILITY.
OVERNIGHT LOWS WILL FALL INTO THE MID TO UPPER 40S FOR MUCH OF THE
REGION. A WEAK DISTURBANCE EMBEDDED IN THE WESTERLY FLOW ALOFT
WILL MOVE ACROSS THE STATE ON SUNDAY AFTERNOON. ANOTHER ROUND OF
ISOLATED TO SCATTERED MOUNTAIN SHOWERS AND THUNDERSTORMS ARE
EXPECTED...WHICH SHOULD DISSIPATE ON SUNDAY EVENING. HIGHS SUNDAY
WILL REACH INTO THE 80S FOR THE LOWER ELEVATIONS.
MONDAY AND MONDAY NIGHT...MODELS IN GOOD AGREEMENT WITH A STRONG
COLD FRONT DROPPING SOUTH ACROSS THE EASTERN PLAINS ON MONDAY
MORNING. THE NAM IS THE FASTEST SOLUTION...WITH IT CLEARING SOUTH
INTO NEW MEXICO BY 12Z...WHILE THE ECMWF AND GFS ARE ABOUT 6 HOURS
SLOWER. FEEL THAT A BIT FASTER SOLUTIONS WILL LIKELY PLAY OUT AND
FOLLOWED THE NAM FRONTAL PROGRESSION. EXPECT LOW LEVEL FLOW TO
TURN EASTERLY AND USHER IN MUCH COOLER AIR INTO THE PLAINS.
UPGLIDE AND MOISTURE BEHIND THE FRONT WILL LIKELY LEAD TO LIGHT
RAIN FOR THE PLAINS THROUGH MONDAY AFTERNOON. WARMER TEMPERATURES
AND GREATER INSTABILITY WILL EXIST OVER THE MOUNTAIN AREAS MONDAY
AFTERNOON AND SCATTERED SHOWERS AND THUNDERSTORMS ARE EXPECTED.
MODELS IN AGREEMENT WITH THE LIGHT RAIN COMING TO AN END FOR THE
PLAINS FROM NORTH TO SOUTH THROUGH THE AFTERNOON HOURS. EXPECT
THUNDERSTORMS OVER THE MOUNTAINS TO DISSIPATE AFTER SUNSET.
TEMPERATURES WILL BE MUCH COOLER BEHIND THE FRONT WITH THE PLAINS
LIKELY ONLY SEEING 60S FOR HIGHS.
TUESDAY THROUGH FRIDAY...THE UPPER PATTERN WILL BECOME AMPLIFIED
ACROSS THE CONUS WITH HIGH PRESSURE BUILDING OVER THE WEST AND A
TROUGH OVER THE EASTERN STATES. THIS WILL PUT SOUTHERN COLORADO
UNDER BROAD NORTHWEST FLOW. EXPECT GENERALLY DRY CONDITIONS ACROSS
THE REGION WITH DAILY AFTERNOON AND EVENING MOUNTAIN CONVECTION
POSSIBLE. TEMPERATURES WILL BE QUICK TO WARM UP WITH 80S FOR THE
LOWER ELEVATIONS THROUGH THE MIDDLE OF THE WEEK.
BY FRIDAY MODELS ARE BRINGING A PIECE OF ENERGY FROM TROPICAL
STORM ODILE WHICH IS FORECAST TO BE OFF THE NORTHERN BAJA COAST BY
FRIDAY. IF THIS DISTURBANCE AND MOISTURE DOES MATERIALIZE...THERE
WILL BE MUCH BETTER CHANCES FOR PRECIPITATION...ESPECIALLY ALONG
THE CONTINENTAL DIVIDE...BY FRIDAY. THIS WILL NEED TO BE
MONITORED. MOZLEY
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT)
ISSUED AT 1125 PM MDT FRI SEP 12 2014
NOT MUCH CHANGE FOR PREVIOUS THINKING...KCOS AND KPUB WILL LIKELY
REMAIN IN MVFR/IFR CONDITIONS THROUGH TOMOROW MORNING. KCOS
SHOULD CLEAR OUT AOA 16-17Z WHILE KPUB AN HOUR OR SO LATER.
OTHERWISE...VFR CONDITIONS ANTICIPATED.
&&
.PUB WATCHES/WARNINGS/ADVISORIES...
FROST ADVISORY UNTIL 8 AM MDT SATURDAY FOR COZ084>086-089.
&&
$$
UPDATE...HODANISH
SHORT TERM...28
LONG TERM...MOZLEY
AVIATION...HODANISH
AREA FORECAST DISCUSSION
NWS TAUNTON MA
356 AM EDT SAT SEP 13 2014
.SYNOPSIS...
HIGH PRESSURE DOMINATES OVERNIGHT. A QUICK MOVING WEATHER SYSTEM
WILL BRING SCATTERED SHOWERS TO THE AREA LATE SATURDAY AFTERNOON
AND EARLY EVENING. HIGH PRESSURE BRINGS DRY WEATHER WITH SLIGHTLY
BELOW NORMAL TEMPERATURES SUNDAY INTO MONDAY. THE NEXT COLD FRONT
WILL LIKELY BRING A PERIOD OF SHOWERS LATE MONDAY NIGHT INTO
TUESDAY. MAINLY DRY WEATHER EXPECTED NEXT WEDNESDAY THROUGH FRIDAY
WITH SLIGHTLY BELOW NORMAL TEMPERATURES CONTINUING.
&&
.NEAR TERM /UNTIL 6 AM THIS MORNING/...
130 AM UPDATE...
ADJUSTED SKY COVER GRIDS BASED ON LATEST OBSERVATIONS AND
SATELLITE PICTURES. RAP SEEMS TO HAVE BEST HANDLE ON PATCHES OF
STRATOCUMULUS. ADJUSTED TEMPERATURES STILL A LITTLE COOLER IN SE
ZONES BASED ON LATEST OBSERVED TRENDS.
1015 PM UPDATE...
QUIET NIGHT WITH LITTLE CHANGE NEEDED IN FORECAST. DID LOWER
HOURLY AND MIN TEMPS FOR PORTIONS OF SE MA AND MARTHAS VINEYARD TO
ACCOUNT FOR CURRENT TRENDS AND CLIMATOLOGY. KEPT POP NEAR ZERO
PERCENT THROUGH 8 AM AND JUST MADE A FEW TWEAKS WITH THE SKY COVER
TO BE CONSISTENT WITH CURRENT TRENDS.
630 PM UPDATE...
STRATO-CUMULUS CLOUDS HAVE DISSIPATED EARLY THIS EVENING ACROSS THE
CAPE AND ISLANDS. OTHERWISE...MAINLY CLEAR SKIES WERE IN PLACE
EARLY THIS EVENING OTHER THAN A TOUCH OF HIGH CLOUDINESS.
IDEAL SEP WEATHER ACROSS THE REGION THROUGH THE EVENING WITH MAINLY
CLEAR SKIES...COMFORTABLE TEMPS AND LIGHT WINDS. AFTER
SUNSET...TEMPS WILL FALL FAIRLY QUICKLY GIVEN DRY
ATMOSPHERE...CLEAR SKIES AND LIGHT WINDS. MANY LOCATIONS WILL DIP
INTO THE MU40S TONIGHT INCLUDING PLACES SUCH AS MARTHAS VINEYARD...
NORWOOD AND OTHER INTERIOR EASTERN MA LOCATIONS. ALSO WESTERN MA AND
SOUTHWEST NH SHOULD FALL INTO THE MU40S. ELSEWHERE MINS WILL BE IN
THE LOW TO MID 50S.
TRICKY PART TO THE FORECAST WILL BE IF SOME LOW CLOUDS ARE ABLE TO
DEVELOP NEAR THE COAST TOWARD DAYBREAK. THESE CLOUDS MAY REAPPEAR
TOWARD SUNRISE GIVEN BLYR COOLING OVERNIGHT. THUS COULD SEE SKIES
BECOME PARTLY TO MOSTLY CLOUDY TOWARD DAYBREAK OVER EASTERN MA AND
POSSIBLY INTO RI...BUT CONFIDENCE IS LOW.
&&
.SHORT TERM /6 AM THIS MORNING THROUGH 6 PM SUNDAY/...
SATURDAY...
DRY TO START THE DAY BUT QUICK MOVING NORTHERN STREAM SHORT WAVE
TROUGH APPROACHES FROM THE WEST. TWO AREAS OF SHOWERS WILL TRACK
ACROSS THE NORTHEAST. FIRST BATCH WILL BE OVER NY STATE AND
NORTHERN NEW ENGLAND WITH PARENT LOW AND ACCOMPANYING LOW TO MID
LEVEL JET. A SECOND AREA OF SHOWERS WILL TRACK SOUTH OF NEW
ENGLAND AS LAST NIGHT/S FRONTAL BOUNDARY LIFTS NORTHWARD WITH
SECONDARY LOW PRES DEVELOPING ON THE FRONT IN RESPONSE TO RRQ OF
THE UPPER JET STREAK. THIS YIELDS LIKELY POPS ACROSS CAPE COD AND
THE ISLANDS WITH CHANCE POPS ELSEWHERE FOR SCATTERED SHOWERS.
GREATEST RISK OF SHOWERS IS SOMEWHERE BETWEEN 4-8 PM. COULD BE
SOME HEAVIER SHOWERS ALONG SOUTH COAST AND OFFSHORE AS PWATS CLIMB
TO 2 INCHES /+2 STD FROM CLIMO/. HOWEVER INSTABILITY ALOFT AND AT
THE SURFACE IS LACKING SO HEAVIER SHOWERS AND THUNDER MAY BE WELL
OFFSHORE. SYSTEM IS VERY PROGRESSIVE SO NOT EXPECTING A SOAKING
RAIN. IN FACT SOME LOCATIONS MAY ONLY SEE A TRACE OF RAINFALL WITH
OTHER LOCATIONS SUCH AS WELL INLAND AND ALONG THE SOUTH COAST
PERHAPS A TENTH OR TWO.
TEMPS A FEW DEGS COOLER THAN TODAY GIVEN THE COOLER START ALONG WITH
INCREASING CLOUDS AND LIGHT ONSHORE WINDS.
SATURDAY NIGHT...
QUICK MOVING SYSTEM EXITS THE REGION BETWEEN 00Z WEST TO PERHAPS 03Z
CAPE COD. EXPECT DECREASING CLOUDS AND DRIER AIR TO OVERSPREAD THE
REGION. NORTHERLY WINDS WILL BECOME GUSTY LATE AT NIGHT AND TOWARD
SUNRISE SUNDAY WITH A FEW GUSTS UP TO 25 MPH POSSIBLE.
&&
.LONG TERM /SUNDAY NIGHT THROUGH FRIDAY/...
HIGHLIGHTS...
* LOW RISK OF PATCHY FROST SUN NIGHT ACROSS DISTANT INTERIOR
* A PERIOD OF SHOWERS LIKELY LATE MON NIGHT/TUE
* DRY WEATHER/SLIGHTLY BELOW NORMAL TEMPS NEXT WED-FRI
OVERVIEW...
OVERALL MODEL GUIDANCE IS IN AGREEMENT WITH A BROAD TROUGH OVER THE
EASTERN HALF OF THE CONTINENT AND A FULL-LATITUDE RIDGE OVER WESTERN
NORTH AMERICA. IN FACT APPEARS THAT THE NORTHERN BRANCH OF THE JET
STREAM REMAINS FAIRLY PROGRESSIVE ESP SINCE THE NAO TRENDING MORE
POSITIVE FOR THE FIRST HALF OF THIS FORECAST. THE FLOW DOES BEGIN TO
BECOME MORE AMPLIFIED TOWARDS THE END OF THE PERIOD AS A TROUGH DIGS
OVER THE EASTERN PACIFIC LEADING TO A RIDGE IN THE CENTRAL
CONUS....ABOUT WHEN THE NAO BECOMES MORE NEUTRAL. HOWEVER IT LOOKS
LIKE THE EASTERN CONUS WILL STILL REMAIN IN A TROUGH PATTERN THROUGH
THE WORK WEEK WITH A POSSIBLE CHANGE IN THE PATTERN BY NEXT WEEKEND.
ONLY MAJOR WEATHER MAKE TO WATCH FOR AT THE MOMENT IS THE SHORTWAVE
PASSING THROUGH MONDAY NIGHT/TUESDAY BRINGING SHOWERS TO THE REGION.
LOW CONFIDENCE ON EXACT TIMING BUT CONFIDENCE IS INCREASING THAT
PRECIP WILL OCCUR.
OTHERWISE HIGH PRESSURE WILL PREVAIL WITH TEMPS AT OR BELOW AVERAGE
FOR THIS TIME OF YEAR. IN FACT SUNDAY NIGHT AND MID TO LATE NEXT
WEEK MAY NEED TO WATCH FOR FROST HEADLINES.
DETAILS...
MONDAY...
A MODIFIED CANADIAN HIGH WILL BUILD INTO NEW ENGLAND DURING THIS
PORTION OF THE FORECAST...CRESTING OVER THE REGION ON MONDAY. LOWS
ON SUN NIGHT WILL BE QUITE CHILLY FOR SEPTEMBER. ALTHOUGH RECORD
COLD IS NOT EXPECTED...WE MAY STILL SEE SOME MIDDLE TO UPPER 30S
ACROSS PORTIONS OF SOUTHWEST NH/NORTHWEST MA...WHERE THIS IS A LOW
RISK FOR SOME PATCHY FROST IN THE TYPICALLY COOLEST OUTLYING
LOCATIONS. FOR MONDAY HIGHS...EVEN WITH FULL SUNSHINE TEMPS WILL
ONLY REACH INTO THE MID 60S TO LOWER 70S...SINCE THE SUN ANGLE IS
LOW. DRY WEATHER WILL PREVAIL.
MONDAY NIGHT INTO TUESDAY...
THE NEXT SHOT FOR ANY SHOWERS WILL BE LATE MONDAY NIGHT INTO
TUESDAY AS ANOTHER SHORTWAVE MOVES THROUGH THE FLOW. OVERALL
GUIDANCE HAS TRENDED TO BE ON THE WETTER SIDE SO CONFIDENCE IS
INCREASING THAT PRECIP WILL OCCUR. RIGHT NOW LOOKS AS IF DROUGHT
STRICKEN RI AND SE MASS HAVE THE BETTER SHOT FOR THE HIGHER QPF
AMOUNTS. ALTHOUGH THE EC DOES HAVE A QPF BULLS-EYE FOR THE
REGION...NOTICED THAT THE GFS HAS TICKED UP SO OVER 0.25 TO 0.5
INCHES IS NOT OUT OF THE QUESTION...ESPECIALLY SINCE PWAT VALUES
DO NOSE IN AT ABOUT 1.5 INCHES. INSTABILITY LOOKS FAIRLY
LIMITED...SO WILL NOT INCLUDE THUNDER IN THE FORECAST AT THIS
TIME. HIGHS SHOULD BE IN THE 60S TO AROUND 70.
END OF THE WORK WEEK...
HIGH PRESSURE FROM CANADA WILL SET UP OVER THE NORTHEAST ON WED
INTO FRIDAY. THE GFS BRING AN ARCTIC FRONT ACROSS THE REGION ON
WED WHILE THE EC HOLDS IT UP UNTIL THURSDAY NIGHT. EITHER WAY
GUIDANCE IS SHOWING 850 MB TEMPS DROPPING BELOW 0C. THIS WILL KEEP
TEMPS WELL BELOW AVERAGE...IN THE 60S RESULTING IN CRISP FALL LIKE
TEMPS. BECAUSE OF THE DIFFERENCE...WILL CONTINUE WITH A BLEND OF
PREV FORECAST AS WELL AS THE ENSEMBLES FOR NOW. EITHER WHICH WAY
WE MAY NEED TO BEGIN TO WATCH FOR THE RISK FOR SOME FROST IN
SOUTHWEST NH/NORTHWEST MA...WHERE WINDS CAN DECOUPLE.
&&
.AVIATION /08Z SATURDAY THROUGH WEDNESDAY/...
FORECASTER CONFIDENCE LEVELS...
LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.
OVERNIGHT...
MODERATE CONFIDENCE. MAIN CHALLENGE ARE A FEW PATCHES OF
STRATOCUMULUS CLOUDS IN 30-35 HUNDRED LAYER. RAP MODEL SEEMS TO
HAVE BEST HANDLE SO FAR ON THIS. LIGHT NORTH TO NORTHEAST WINDS
EXPECTED TO BECOME MORE FROM THE EAST TO NORTHEAST AFTER DAYBREAK.
SATURDAY...
MVFR CIGS EXPECTED TO DEVELOP FROM WEST TO EAST AND SOUTH TO NORTH
DURING THE AFTERNOON. SCATTERED SHOWERS MOST LIKELY AFTER 20Z WITH
SOME MOVING FROM WEST TO EAST AND A SECOND AREA SOUTHWEST TO
NORTHEAST TOWARD THE CAPE AND ISLANDS.
SAT NIGHT...
MVFR CIGS IN SCATTERED SHOWERS WITH PATCHES OF IFR CIGS POSSIBLE
SE COASTAL AREAS. CONDITIONS IMPROVING TO VFR BY 03Z WEST AND BY
06Z EAST. MODEST NNE WIND DEVELOPS 06Z- 12Z WITH GUSTS UP TO
20-25 KT POSSIBLE E COASTAL AREAS.
KBOS TERMINAL...MODERATE CONFIDENCE IN TAF. CIGS BKN030 POSSIBLE A
FEW HOURS ON EITHER SIDE OF SUNRISE...THEN PROBABLY A PERIOD OF
VFR MID TO LATE MORNING BEFORE CIGS LOWERING TO MVFR RANGE BY MID
OR LATE AFTERNOON. SCATTERED SHOWERS MAY LOWER VSBYS TO MVFR
THRESHOLDS FOR A TIME LATE AFTERNOON/EARLY EVENING. GREATEST RISK
OF SHOWERS 20Z SAT THRU 03Z SUN. CONDITIONS IMPROVING AFTER 03Z
SUN.
KBDL TERMINAL...MODERATE TO HIGH CONFIDENCE. GREATEST RISK OF
SHOWERS 18Z SAT THRU 00Z SUNDAY WITH A PERIOD OR TWO OF MVFR CIGS
AND VSBYS POSSIBLE.
OUTLOOK...SUNDAY NIGHT THROUGH WEDNESDAY...HIGH CONFIDENCE.
MAINLY VFR CONDITIONS OVER THIS TIME...EXCEPT FOR A PERIOD OF MVFR-
IFR CONDITIONS LATE MON NIGHT/TUE IN A ROUND OF SHOWERS.
&&
.MARINE...
FORECASTER CONFIDENCE LEVELS...
LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.
FORECAST CONFIDENCE IS MODERATE TO HIGH THROUGH SUNDAY.
OVERNIGHT...LIGHT EAST TO NORTHEAST WINDS...DRY WEATHER AND GOOD
VSBY.
SATURDAY...GENERALLY LIGHT EASTERLY WINDS. ONE AREA OF LOW PRES
TRACKS NE INTO NY STATE AND ANOTHER WEAK LOW FORMS OFF THE NJ
COAST. CHANCE OF SHOWERS LATE IN THE DAY WITH A LOW RISK OF
THUNDER WELL SOUTH OF NEW ENGLAND.
SAT NIGHT...WEAK LOW PRES MOVES NE ACROSS GEORGES BANK. A MODEST
NORTH WIND DEVELOPS WITH A CHANCE OF GUSTS TO NEAR 25 KT LATE.
SCATTERED SHOWERS DURING THE EVENING GIVES WAY TO DRY WEATHER AND
GOOD VSBY.
OUTLOOK...SUNDAY NIGHT THROUGH WEDNESDAY....
MONDAY INTO TUE MORNING...MODERATE TO HIGH CONFIDENCE. HIGH
PRESSURE NEARBY WILL RESULT IN A WEAK PRESSURE GRADIENT KEEPING
WINDS/SEAS BELOW SCA THRESHOLDS.
TUESDAY AFTERNOON INTO WEDNESDAY...MODERATE CONFIDENCE. MAY SEE
SOME MARGINAL SCA WINDS/SEAS ACROSS THE OUTER-WATERS BEHIND A COLD
FRONT/LOW PRESSURE SYSTEM IN THE COOL AIR ADVECTION PATTERN.
&&
.BOX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
MA...NONE.
NH...NONE.
RI...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...NOCERA/DUNTEN
NEAR TERM...FRANK/NOCERA/THOMPSON
SHORT TERM...NOCERA
LONG TERM...DUNTEN
AVIATION...NOCERA/DUNTEN/THOMPSON
MARINE...NOCERA/DUNTEN/THOMPSON
AREA FORECAST DISCUSSION
NWS TAUNTON MA
158 AM EDT SAT SEP 13 2014
.SYNOPSIS...
HIGH PRESSURE DOMINATES OVERNIGHT. A QUICK MOVING WEATHER SYSTEM
WILL BRING SCATTERED SHOWERS TO THE AREA LATE SATURDAY AFTERNOON
AND EARLY EVENING. HIGH PRESSURE BRINGS DRY WEATHER WITH SLIGHTLY
BELOW NORMAL TEMPERATURES SUNDAY INTO MONDAY. THE NEXT COLD FRONT
WILL LIKELY BRING A PERIOD OF SHOWERS LATE MONDAY NIGHT INTO
TUESDAY. MAINLY DRY WEATHER EXPECTED NEXT WEDNESDAY THROUGH FRIDAY
WITH SLIGHTLY BELOW NORMAL TEMPERATURES CONTINUING.
&&
.NEAR TERM /UNTIL 6 AM THIS MORNING/...
130 AM UPDATE...
ADJUSTED SKY COVER GRIDS BASED ON LATEST OBSERVATIONS AND
SATELLITE PICTURES. RAP SEEMS TO HAVE BEST HANDLE ON PATCHES OF
STRATOCUMULUS. ADJUSTED TEMPERATURES STILL A LITTLE COOLER IN SE
ZONES BASED ON LATEST OBSERVED TRENDS.
1015 PM UPDATE...
QUIET NIGHT WITH LITTLE CHANGE NEEDED IN FORECAST. DID LOWER
HOURLY AND MIN TEMPS FOR PORTIONS OF SE MA AND MARTHAS VINEYARD TO
ACCOUNT FOR CURRENT TRENDS AND CLIMATOLOGY. KEPT POP NEAR ZERO
PERCENT THROUGH 8 AM AND JUST MADE A FEW TWEAKS WITH THE SKY COVER
TO BE CONSISTENT WITH CURRENT TRENDS.
630 PM UPDATE...
STRATO-CUMULUS CLOUDS HAVE DISSIPATED EARLY THIS EVENING ACROSS THE
CAPE AND ISLANDS. OTHERWISE...MAINLY CLEAR SKIES WERE IN PLACE
EARLY THIS EVENING OTHER THAN A TOUCH OF HIGH CLOUDINESS.
IDEAL SEP WEATHER ACROSS THE REGION THROUGH THE EVENING WITH MAINLY
CLEAR SKIES...COMFORTABLE TEMPS AND LIGHT WINDS. AFTER
SUNSET...TEMPS WILL FALL FAIRLY QUICKLY GIVEN DRY
ATMOSPHERE...CLEAR SKIES AND LIGHT WINDS. MANY LOCATIONS WILL DIP
INTO THE MU40S TONIGHT INCLUDING PLACES SUCH AS MARTHAS VINEYARD...
NORWOOD AND OTHER INTERIOR EASTERN MA LOCATIONS. ALSO WESTERN MA AND
SOUTHWEST NH SHOULD FALL INTO THE MU40S. ELSEWHERE MINS WILL BE IN
THE LOW TO MID 50S.
TRICKY PART TO THE FORECAST WILL BE IF SOME LOW CLOUDS ARE ABLE TO
DEVELOP NEAR THE COAST TOWARD DAYBREAK. THESE CLOUDS MAY REAPPEAR
TOWARD SUNRISE GIVEN BLYR COOLING OVERNIGHT. THUS COULD SEE SKIES
BECOME PARTLY TO MOSTLY CLOUDY TOWARD DAYBREAK OVER EASTERN MA AND
POSSIBLY INTO RI...BUT CONFIDENCE IS LOW.
&&
.SHORT TERM /6 AM THIS MORNING THROUGH 6 PM SUNDAY/...
SATURDAY...
DRY TO START THE DAY BUT QUICK MOVING NORTHERN STREAM SHORT WAVE
TROUGH APPROACHES FROM THE WEST. TWO AREAS OF SHOWERS WILL TRACK
ACROSS THE NORTHEAST. FIRST BATCH WILL BE OVER NY STATE AND
NORTHERN NEW ENGLAND WITH PARENT LOW AND ACCOMPANYING LOW TO MID
LEVEL JET. A SECOND AREA OF SHOWERS WILL TRACK SOUTH OF NEW
ENGLAND AS LAST NIGHT/S FRONTAL BOUNDARY LIFTS NORTHWARD WITH
SECONDARY LOW PRES DEVELOPING ON THE FRONT IN RESPONSE TO RRQ OF
THE UPPER JET STREAK. THIS YIELDS LIKELY POPS ACROSS CAPE COD AND
THE ISLANDS WITH CHANCE POPS ELSEWHERE FOR SCATTERED SHOWERS.
GREATEST RISK OF SHOWERS IS SOMEWHERE BETWEEN 4-8 PM. COULD BE
SOME HEAVIER SHOWERS ALONG SOUTH COAST AND OFFSHORE AS PWATS CLIMB
TO 2 INCHES /+2 STD FROM CLIMO/. HOWEVER INSTABILITY ALOFT AND AT
THE SURFACE IS LACKING SO HEAVIER SHOWERS AND THUNDER MAY BE WELL
OFFSHORE. SYSTEM IS VERY PROGRESSIVE SO NOT EXPECTING A SOAKING
RAIN. IN FACT SOME LOCATIONS MAY ONLY SEE A TRACE OF RAINFALL WITH
OTHER LOCATIONS SUCH AS WELL INLAND AND ALONG THE SOUTH COAST
PERHAPS A TENTH OR TWO.
TEMPS A FEW DEGS COOLER THAN TODAY GIVEN THE COOLER START ALONG WITH
INCREASING CLOUDS AND LIGHT ONSHORE WINDS.
SATURDAY NIGHT...
QUICK MOVING SYSTEM EXITS THE REGION BETWEEN 00Z WEST TO PERHAPS 03Z
CAPE COD. EXPECT DECREASING CLOUDS AND DRIER AIR TO OVERSPREAD THE
REGION. NORTHERLY WINDS WILL BECOME GUSTY LATE AT NIGHT AND TOWARD
SUNRISE SUNDAY WITH A FEW GUSTS UP TO 25 MPH POSSIBLE.
&&
.LONG TERM /SUNDAY NIGHT THROUGH FRIDAY/...
HIGHLIGHTS...
* DRY WITH SLIGHTLY BELOW NORMAL TEMPS SUN/MON
* LOW RISK OF PATCHY FROST SUN NIGHT ACROSS DISTANT INTERIOR
* A PERIOD OF SHOWERS LIKELY LATE MON NIGHT/TUE
* DRY WEATHER/SLIGHTLY BELOW NORMAL TEMPS NEXT WED-FRI
DETAILS...
SUNDAY AND MONDAY...
LARGE HIGH PRESSURE WILL BE ANCHORED OVER SOUTHERN NEW ENGLAND SUN
AND MON. THIS WILL RESULT IN DRY WEATHER WITH SLIGHTLY BELOW NORMAL
HIGH TEMPS. HIGHS SUN AND MON WILL BE IN THE 60S...TO LOWER 70S.
LOWS SUN NIGHT WILL BE QUITE CHILLY FOR MID SEPTEMBER. MAY SEE SOME
MIDDLE TO UPPER 30S ACROSS PORTIONS OF SOUTHWEST NH/NORTHWEST MA...
WHERE THIS IS A LOW RISK FOR SOME PATCHY FROST IN THE TYPICALLY
COOLEST OUTLYING LOCATIONS. MOST OTHER AREAS WILL SEE LOWS IN THE
40S.
MONDAY NIGHT AND TUESDAY...
A POTENT SHORTWAVE/COLD FRONT WILL BE APPROACHING SOUTHERN NEW
ENGLAND LATE MON NIGHT INTO TUE. THIS SHOULD RESULT IN A PERIOD OF
RAIN SHOWERS...BUT EXACT TIMING IS UNCERTAIN AT THIS POINT. ITS
POSSIBLE WE COULD EVEN SEE A PERIOD OF HEAVY RAIN IF THE MORE
AMPLIFIED ECMWF MODEL IS CORRECT...BUT GFS/GGEM ARE A TAMER WITH THE
SHORTWAVE SO THAT IS UNCERTAIN. INSTABILITY LOOKS FAIRLY
LIMITED...SO WILL NOT INCLUDE THUNDER IN THE FORECAST AT THIS TIME.
HIGHS SHOULD BE IN THE 60S TO AROUND 70.
WEDNESDAY THROUGH FRIDAY...
HIGH PRESSURE BUILDS IN BEHIND THE COLD FRONT WED INTO FRI. THIS
SHOULD RESULT IN MAINLY DRY WEATHER WITH SLIGHTLY BELOW NORMAL TEMPS
FOR THE END OF THE WORK WEEK. WE MAY HAVE TO DEAL WITH THE RISK
FOR SOME FROST IN SOUTHWEST NH/NORTHWEST MA...WHERE WINDS CAN
DECOUPLE.
&&
.AVIATION /06Z SATURDAY THROUGH WEDNESDAY/...
FORECASTER CONFIDENCE LEVELS...
LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.
OVERNIGHT...
MODERATE CONFIDENCE. MAIN CHALLENGE ARE A FEW PATCHES OF
STRATOCUMULUS CLOUDS IN 30-35 HUNDRED LAYER. RAP MODEL SEEMS TO
HAVE BEST HANDLE SO FAR ON THIS. LIGHT NORTH TO NORTHEAST WINDS
EXPECTED TO BECOME MORE FROM THE EAST TO NORTHEAST AFTER DAYBREAK.
SATURDAY...
MVFR CIGS EXPECTED TO DEVELOP FROM WEST TO EAST AND SOUTH TO NORTH
DURING THE AFTERNOON. SCATTERED SHOWERS MOST LIKELY AFTER 20Z WITH
SOME MOVING FROM WEST TO EAST AND A SECOND AREA SOUTHWEST TO
NORTHEAST TOWARD THE CAPE AND ISLANDS.
SAT NIGHT...
MVFR CIGS IN SCATTERED SHOWERS WITH PATCHES OF IFR CIGS POSSIBLE
SE COASTAL AREAS. CONDITIONS IMPROVING TO VFR BY 03Z WEST AND BY
06Z EAST. MODEST NNE WIND DEVELOPS 06Z- 12Z WITH GUSTS UP TO
20-25 KT POSSIBLE E COASTAL AREAS.
KBOS TERMINAL...MODERATE CONFIDENCE IN TAF. CIGS BKN030 POSSIBLE A
FEW HOURS ON EITHER SIDE OF SUNRISE...THEN PROBABLY A PERIOD OF
VFR MID TO LATE MORNING BEFORE CIGS LOWERING TO MVFR RANGE BY MID
OR LATE AFTERNOON. SCATTERED SHOWERS MAY LOWER VSBYS TO MVFR
THRESHOLDS FOR A TIME LATE AFTERNOON/EARLY EVENING. GREATEST RISK
OF SHOWERS 20Z SAT THRU 03Z SUN. CONDITIONS IMPROVING AFTER 03Z
SUN.
KBDL TERMINAL...MODERATE TO HIGH CONFIDENCE. GREATEST RISK OF
SHOWERS 18Z SAT THRU 00Z SUNDAY WITH A PERIOD OR TWO OF MVFR CIGS
AND VSBYS POSSIBLE.
OUTLOOK...SUNDAY THROUGH WEDNESDAY...MODERATE TO HIGH CONFIDENCE.
MAINLY VFR CONDITIONS OVER THIS TIME...EXCEPT FOR A PERIOD OF
MVFR-IFR CONDITIONS LATE MON NIGHT/TUE IN A ROUND OF SHOWERS AND
PERHAPS SOME LOW CLOUDS/FOG PATCHES.
&&
.MARINE...
FORECASTER CONFIDENCE LEVELS...
LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.
FORECAST CONFIDENCE IS MODERATE TO HIGH THROUGH SUNDAY.
OVERNIGHT...LIGHT EAST TO NORTHEAST WINDS...DRY WEATHER AND GOOD
VSBY.
SATURDAY...GENERALLY LIGHT EASTERLY WINDS. ONE AREA OF LOW PRES
TRACKS NE INTO NY STATE AND ANOTHER WEAK LOW FORMS OFF THE NJ
COAST. CHANCE OF SHOWERS LATE IN THE DAY WITH A LOW RISK OF
THUNDER WELL SOUTH OF NEW ENGLAND.
SAT NIGHT...WEAK LOW PRES MOVES NE ACROSS GEORGES BANK. A MODEST
NORTH WIND DEVELOPS WITH A CHANCE OF GUSTS TO NEAR 25 KT LATE.
SCATTERED SHOWERS DURING THE EVENING GIVES WAY TO DRY WEATHER AND
GOOD VSBY.
OUTLOOK...SUNDAY THROUGH WEDNESDAY....
SUNDAY...MODERATE TO HIGH CONFIDENCE. MAY HAVE SOME MARGINAL SCA
NORTHERLY WIND GUSTS/SEAS ACROSS THE EASTERN WATERS SUN MORNING IN
THE COOL ADVECTION PATTERN. WINDS/SEAS SHOULD DIMINISH SUN
AFTERNOON AS PRESSURE GRADIENT WEAKENS.
MONDAY INTO TUE MORNING...MODERATE TO HIGH CONFIDENCE. HIGH
PRESSURE NEARBY WILL RESULT IN A WEAK PRESSURE GRADIENT KEEPING
WINDS/SEAS BELOW SCA THRESHOLDS.
TUESDAY AFTERNOON INTO WEDNESDAY...MODERATE CONFIDENCE. MAY SEE
SOME MARGINAL SCA WINDS/SEAS ACROSS THE OUTER-WATERS BEHIND A COLD
FRONT/LOW PRESSURE SYSTEM IN THE COOL AIR ADVECTION PATTERN.
&&
.BOX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
MA...NONE.
NH...NONE.
RI...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...FRANK/NOCERA
NEAR TERM...FRANK/NOCERA/THOMPSON
SHORT TERM...NOCERA
LONG TERM...FRANK
AVIATION...FRANK/NOCERA/THOMPSON
MARINE...FRANK/NOCERA/THOMPSON
AREA FORECAST DISCUSSION
NWS MIAMI FL
431 AM EDT SAT SEP 13 2014
.SHORT TERM...(TODAY-MONDAY)
RECENTLY ANIMATED WATER VAPOR LOOP SHOWED AN UPPER LOW CENTERED OVER
SOUTH FLORIDA SLOWLY TRACKING WESTWARD AND A RIDGE AXIS ORIENTED
FROM EAST TO WEST ACROSS THE NORTHERN GULF COAST STATES. PLENTY OF
DEEP LAYER MOISTURE EAST OF THIS UPPER LOW COMBINED WITH UPPER-LEVEL
DIVERGENCE WILL CONTINUE TO SUPPORT WIDESPREAD RAINFALL TODAY
...ESPECIALLY ALONG THE SOUTHEAST COAST AND ACROSS THE ATLANTIC
WATERS THROUGH THE MORNING HOURS. THE LATEST HRRR MODEL RUN APPEARS
TO HAVE INITIALIZED WELL WITH THE CURRENT RADAR TRENDS AND GENERALLY
INDICATES THIS MORNING ACTIVITY CONTINUING ACROSS THE EASTERN
AREAS INCLUDING PALM BEACH, BROWARD AND MIAMI-DADE BEFORE SHIFTING
INLAND AND TOWARD THE GULF COAST THROUGH THE MID TO LATE
AFTERNOON/EARLY EVENING PERIOD. THIS SOLUTION MAKES SENSE WITH THE
UPPER LOW SHIFTING WESTWARD AND LIGHT TO MODERATE SOUTHEAST LOW-
LEVEL FLOW CONTINUING. THIS PATTERN WILL KEEP THE POTENTIAL FOR
LOCALIZED FLOODING UP THROUGH THIS EVENING...ESPECIALLY OVER THE
AREAS THAT ARE ALREADY SATURATED FROM EARLIER RAINFALL (AREAS HAVE
RECEIVED 2-4 INCHES WITH HIGHER AMOUNTS UP TO 7" JUST INLAND OF
BOCA RATON OVER THE PAST 24-36 HRS). MODEL SOUNDINGS SUPPORT THE
ACTIVITY TAPERING OFF OVER THE FAR SOUTHEASTERN AREAS OR TOWARD
MIAMI THROUGH THE MORNING AND AFTERNOON HOURS WITH MAINLY
SATURATED PROFILES ABOVE A SLIGHTLY DRIER LAYER FROM THE SURFACE
TO 700MB. AS A RESULT...MAXIMUM TEMPERATURES HAVE BEEN SLIGHTLY
UNDERCUT BY A FEW DEGREES COMPARED TO GUIDANCE...MAINLY DUE TO
PLENTY OF CLOUD COVERAGE ANTICIPATED. IF THIS COVERAGE BEGINS TO
BREAK THROUGH THE DAY...TEMPERATURES WILL NEED TO BE ADJUSTED
ACCORDINGLY. THE MOIST TREND WITH SOUTHEAST FLOW WILL PERSIST
THROUGH SUNDAY BEFORE SOME DRIER AIR MOVES IN FROM THE WEST AND
THE RIDGE BUILDS BACK ACROSS THE REGION INTO THE UPCOMING WEEK.
/85
.LONG TERM (TUESDAY-FRIDAY)...
THE LATEST EXTENDED GUIDANCE REMAINS IN DECENT AGREEMENT ON THE
LARGE SCALE AND GENERALLY INDICATES FALLING UPPER HEIGHTS IN
RESPONSE TO A DEEPENING UPPER TROUGH ACROSS THE REGION. A FRONTAL
BOUNDARY IS PROJECTED TO SHIFT SOUTHWARD AND STALL NORTH OF THE AREA
THROUGH THE SECOND HALF OF THE WEEK. THE ECMWF SEEMS TO BE THE MORE
BULLISH SOLUTION AND SHOWS THE MOISTURE AXIS ASSOCIATED WITH THIS
BOUNDARY PROGRESSING FARTHER SOUTH THAN THE GFS/GFS ENSEMBLE MEAN
WITH SSW LOW-LEVEL FLOW SETTING UP OVER THE AREA BY THURSDAY. THE
COMBINATION OF THE FRONT AND FALLING UPPER HEIGHTS ALONG WITH SSW
LOW-LEVEL FLOW WOULD FAVOR MUCH OF THE RAINFALL SETTING UP OVER THE
EAST COAST/METRO AREAS BY THURSDAY.
/85
&&
.AVIATION...
A LARGE AREA OF SHOWERS AND THUNDERSTORMS OVER THE ATLANTIC WATERS
WERE DEVELOPING ON THE NORTHEAST SIDE OF THE MID/UPPER LEVEL
VORTICITY MOVING WEST ACROSS THE FLORIDA STRAITS. THESE
SHOWERS/STORMS WERE MOVING QUICKLY TO THE NORTHWEST TOWARDS THE
BROWARD AND MIAMI-DADE TAF SITES...AND THEY MAY MOVE OVER THE TAF
SITES THROUGH THE EARLY MORNING HOURS. BRIEF MVFR/IFR CONDITIONS AND
GUSTY WINDS UP TO 30 KNOTS ARE POSSIBLE. THE AREA OF LOW PRESSURE
OVER THE SOUTHEAST GULF AND THE UPPER LEVEL LOW WILL CONTINUE TO
MOVE WEST TODAY AND HAVE LESS OF AN INFLUENCE OVER THE REGION
THROUGHOUT THE DAY. THIS COMBINED WITH THE OVERNIGHT CONVECTION MAY
LIMIT SHOWER/STORM DEVELOPMENT FOR THE EAST COAST METRO AREAS DURING
THE DAY. HOWEVER...DEEP MOISTURE IN THE SOUTHEAST LOW LEVEL FLOW
WILL CONTINUE...SO KEPT VCTS IN FOR THE TAF SITES. AT KAPF...SHOWER
AND STORM DEVELOPMENT IS FORECAST TO BECOME MORE LIKELY AS THE DAY
PROGRESSES...AS THE INFLUENCE OF THE UPPER LOW INCREASES. LIGHT
WINDS WILL CONTINUE THROUGH THE OVERNIGHT HOURS OUTSIDE OF SHOWERS
AND STORMS...AND THEN BECOME SOUTHEAST AROUND 10 KNOTS DURING THE
DAY.
/84
&&
.MARINE...
AN UPPER LOW WILL KEEP THE RAIN CHANCES IN THE FORECAST ACROSS THE
MARINE AREAS THROUGH THE REMAINDER OF THE WEEKEND WITH LIGHT TO
MODERATE SOUTHEAST WINDS CONTINUING. WINDS AND SEAS WILL BE LOCALLY
HIGHER IN AND AROUND HEAVIER SHOWERS AND STORMS. HIGH PRESSURE WILL
BUILD BACK ACROSS THE REGION THROUGH THE FIRST HALF OF THE UPCOMING
WEEK WITH SOUTHEAST WINDS CONTINUING.
&&
.PRELIMINARY POINT TEMPS/POPS...
WEST PALM BEACH 87 76 87 76 / 40 30 50 30
FORT LAUDERDALE 84 77 87 79 / 50 40 60 20
MIAMI 85 77 87 78 / 50 40 60 20
NAPLES 87 75 89 76 / 70 30 60 20
&&
.MFL WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
AM...NONE.
GM...NONE.
&&
$$
DISCUSSION...85/AG
AVIATION....84/AK
AREA FORECAST DISCUSSION
NWS MIAMI FL
205 AM EDT SAT SEP 13 2014
.AVIATION...
A LARGE AREA OF SHOWERS AND THUNDERSTORMS OVER THE ATLANTIC WATERS
WERE DEVELOPING ON THE NORTHEAST SIDE OF THE MID/UPPER LEVEL
VORTICITY MOVING WEST ACROSS THE FLORIDA STRAITS. THESE
SHOWERS/STORMS WERE MOVING QUICKLY TO THE NORTHWEST TOWARDS THE
BROWARD AND MIAMI-DADE TAF SITES...AND THEY MAY MOVE OVER THE TAF
SITES THROUGH THE EARLY MORNING HOURS. BRIEF MVFR/IFR CONDITIONS
AND GUSTY WINDS UP TO 30 KNOTS ARE POSSIBLE. THE AREA OF LOW
PRESSURE OVER THE SOUTHEAST GULF AND THE UPPER LEVEL LOW WILL
CONTINUE TO MOVE WEST TODAY AND HAVE LESS OF AN INFLUENCE OVER THE
REGION THROUGHOUT THE DAY. THIS COMBINED WITH THE OVERNIGHT
CONVECTION MAY LIMIT SHOWER/STORM DEVELOPMENT FOR THE EAST COAST
METRO AREAS DURING THE DAY. HOWEVER...DEEP MOISTURE IN THE
SOUTHEAST LOW LEVEL FLOW WILL CONTINUE...SO KEPT VCTS IN FOR THE TAF
SITES. AT KAPF...SHOWER AND STORM DEVELOPMENT IS FORECAST TO
BECOME MORE LIKELY AS THE DAY PROGRESSES...AS THE INFLUENCE OF THE
UPPER LOW INCREASES. LIGHT WINDS WILL CONTINUE THROUGH THE
OVERNIGHT HOURS OUTSIDE OF SHOWERS AND STORMS...AND THEN BECOME
SOUTHEAST AROUND 10 KNOTS DURING THE DAY.
&&
.PREV DISCUSSION... /ISSUED 944 PM EDT FRI SEP 12 2014/
UPDATE...
ONLY MADE SOME MINOR ADJUSTMENTS TO THE POP GRIDS THIS EVENING.
COULD HAVE LOWERED THEM EVEN MORE THAN I DID, BUT THESE TROPICAL
TYPE SMALL LOW LEVEL CIRCULATIONS CAN BEGIN TO DEVELOP CONVECTION
AT ANY TIME GIVEN THE SOUTHEASTERLY FLOW ON THE EAST SIDE WITH
DEEP TROPICAL AIRMASS. SO EVEN THOUGH NOT MUCH GOING ON AT THE
CURRENT TIME, WAS A LITTLE HESITANT IN MAKING TOO DRASTIC OF A CUT
IN THE POPS. THE HRRR KEEPS THE ACTION QUIET SO LATER UPDATES MAY
BE NEEDED TO LOWER CHANCES MORE IF TRENDS DICTATE.
KOB
PREV DISCUSSION... /ISSUED 739 PM EDT FRI SEP 12 2014/
AVIATION...
LOW PRESSURE CENTERED JUST NORTH OF NAPLES THIS EVENING WILL
CONTINUE DRIFTING WEST INTO THE GULF OF MEXICO...BUT WILL BE THE
MAJOR INFLUENCE ON SOUTH FLORIDA WEATHER THROUGH THE TAF PERIOD.
APPEARS TSRA THREAT OVERNIGHT IS MINIMAL...SO ELECTED TO HAVE VCSH
IN FORECAST INTO SATURDAY MORNING. BY 15Z...SCATTERED/NUMEROUS
SHOWERS/TSTMS EXPECTED...HANDLED NOW BY VCTS BUT TEMPO GROUPS MAY
BE NEEDED ONCE TIMING/COVERAGE BECOME MORE CERTAIN. ESE WINDS WILL
DIMINISH TO 5 KTS OR LESS TONIGHT...THEN INCREASE TO 10-15 KTS BY
SAT AFTN.
PREV DISCUSSION... /ISSUED 344 PM EDT FRI SEP 12 2014/
DISCUSSION...
RECENT WATER VAPOR IMAGERY AND THE LATEST GUIDANCE INDICATES AN
UPPER LEVEL LOW JUST TO THE NORTH OF THE NORTHERN BAHAMAS AND IS
FORECAST TO RETROGRADE WESTWARD TONIGHT INTO SATURDAY.
ELEVATED CHANCES OF SHOWERS AND THUNDERSTORMS ARE FORECAST ACROSS
THE REGION TONIGHT INTO SATURDAY. AS THE SURFACE LOW CONTINUES TO
TRACK WESTWARD TONIGHT...IT IS FORECAST TO ENTER THE GULF WATERS
WITH LOW LEVEL SOUTHEASTERLY WINDS FORECAST TO CONTINUE BRINGING
IN DEEP TROPICAL MOISTURE INTO THE REGION TONIGHT INTO SATURDAY.
FOR TONIGHT...THE AFOREMENTIONED UPPER LEVEL LOW IS FORECAST TO
DRIFT WESTWARD WITH 500 HPA VORTICITY FORECAST TO PASS ACROSS THE
REGION TONIGHT INTO SATURDAY. THUS THE INGREDIENTS FOR ADDITIONAL
SHOWERS AND THUNDERSTORMS WILL CONTINUE TONIGHT INTO SATURDAY WITH
ELEVATED POP`S INDICATED IN THE FORECAST.
FOR SATURDAY...WILE THE UPPER LEVEL LOW MAY BE LESS OF A FACTOR AS
IT IS FORECAST TO CONTINUE MOVING WESTWARD...THE SURFACE LOW IS
FORECAST TO BE IN THE EASTERN GULF WITH LOW LEVEL SOUTHEASTERLY
WINDS CONTINUING TO ADVECT ADDITIONAL DEEP MOISTURE INTO THE
REGION. NUMEROUS SHOWERS AND SCATTERED THUNDERSTORMS ARE FORECAST
FOR SATURDAY AFTERNOON AND EARLY EVENING HOURS. BY SUNDAY
TROPICAL MOISTURE IS FORECAST TO REMAIN ACROSS THE REGION WITH DAY
TIME HEATING LIKELY TO DEVELOP AFTERNOON SHOWERS AND
THUNDERSTORMS. THE EXTENDED GUIDANCE INDICATES SOME RELATIVELY
DRIER AIR ENTERING THE REGION EARLY NEXT WEEK.
MARINE...
WINDS ARE FORECAST TO BE FROM 10 TO 15 KNOTS THROUGH SATURDAY
THEN DECREASING INTO SUNDAY TO AROUND 10 KNOTS. SEAS 2 TO 3 FEET
POSSIBLE TODAY INTO SATURDAY THEN DECREASING TO 2 FEET OR LESS BY
SUNDAY.
&&
.PRELIMINARY POINT TEMPS/POPS...
WEST PALM BEACH 87 76 87 76 / 60 40 50 20
FORT LAUDERDALE 87 77 88 79 / 60 50 50 30
MIAMI 88 77 88 78 / 60 40 40 20
NAPLES 88 74 89 76 / 70 40 60 20
&&
.MFL WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
AM...NONE.
GM...NONE.
&&
$$
SHORT TERM...85/AG
LONG TERM....85/AG
AVIATION...84/AK
AREA FORECAST DISCUSSION
NWS SHREVEPORT LA
1207 AM CDT SAT SEP 13 2014
.AVIATION...
FOR THE 13/00Z TAFS...SCT SHWRS PERSIST GENERALLY ALONG AND S OF
THE I-20 CORRIDOR BUT RADAR LOOPS OVER THE LAST HOUR INDICATE
PRECIP IS BEGINNING TO DISSIPATE. HAVE INCLUDED SOME MENTION OF
RAIN AT A FEW OF THE TAFS SITES FOR THE ONGOING ACTIVITY. CIGS ARE
MVFR/IFR...GENERALLY AROUND OR BELOW 1000 KFT. ONLY A VERY SLIGHT
IMPROVEMENT IS ANTICIPATED THROUGH THE REMAINDER OF THE TAF PERIOD
AS CIGS LIFT SOMEWHAT BUT WILL LIKELY NOT LIFT ABOVE MVFR. POST-
FRONTAL PRESSURE GRADIENT REMAINS TIGHT AND NLY WINDS WILL PERSIST
AROUND 10 KTS WITH A FEW HIGHER GUSTS BUT SPEEDS SHOULD GRADUALLY
DIMINISH AND EVENTUALLY DROP TO AROUND 5 KTS AFTER 14/00Z AS A SFC
HIGH BUILDS INTO THE AREA. /09/
&&
.PREV DISCUSSION... /ISSUED 1015 PM CDT FRI SEP 12 2014/
DISCUSSION...
COLD FRONT SOUTH OF INTERSTATE 20 AND NEARING THE SOUTHERN PARTS
OF EAST AND NORTHEAST TEXAS ACROSS LOWER PARTS OF NORTHWEST AND
NORTH CENTRAL LOUISIANA LATE THIS EVENING. RAIN AND EMBEDDED
HEAVIER SHOWERS CONTINUED ALONG AND IN WAKE OF THE COLD FRONT
AS MOISTURE LIFTS NEAR THE BOUNDARY AND COOLS IN THE COOLER AIR TO
THE RADAR OF THE BOUNDARY. HAVE REMOVED THUNDERSTORMS FROM THE
WORDING OF THE ZONES FOR THE REST OF TONIGHT AND INTO TOMORROW.
SOME ISOLATED THUNDERSTORMS MAY OCCUR BUT MOST LOCATIONS WILL NOT
HAVE THUNDERSTORMS. RAIN WILL TAPER OFF FROM NORTHWEST TO SOUTHEAST.
ADJUSTED THE TEMPERATURES LOWER FOR PARTS OF EAST AND NORTHEAST
TEXAS AND SOUTHEAST OKLAHOMA...WHERE COLD AIR WILL MORE PRONE TO
ENTER THE REGION. /06/
PREV DISCUSSION... /ISSUED 348 PM CDT FRI SEP 12 2014/
DISCUSSION...
OUR WEAK COLD FRONT REMAINS STATIONARY JUST S OF THE I-20 CORRIDOR
OF E TX/N LA THIS AFTERNOON...WITH A LARGE SUCKER HOLE RECENTLY
OPENING UP ACROSS NW LA. TEMPS IN THESE AREAS HAVE WARMED INTO THE
LOWER/MID 80S THIS AFTERNOON...BUT TEMPS REMAIN MUCH COOLER UNDER
THE LOW STRATUS FARTHER W AND N. AS EXPECTED...SCT CONVECTION HAS
DEVELOPED ALONG THE FRONTAL ZONE OVER DEEP E TX...WITH THE WEAK
SEABREEZE APPROACHING THIS AREA AS WELL AS WCNTRL LA FROM SE TX/SW
LA. BELIEVE THAT THIS CONVECTION WILL CONTINUE THROUGH A PORTION
OF THIS EVENING BEFORE DIMINISHING WITH THE LOSS OF
HEATING/INSTABILITY...WITH THE FRONTAL BNDRY EXPECTED TO SLOWLY
DRIFT BACK S ACROSS THIS AREA AND THE SRN SECTIONS OF NCNTRL LA
THIS EVENING/OVERNIGHT. THE HRRR AND TO SOME EXTENT...THE 12Z WRF
DOES INDICATE THE ONGOING CONVECTION POSSIBLY BUILDING BACK A
LITTLE FARTHER NNE TO NEAR/JUST S OF THE I-20 CORRIDOR OF E TX/NW
LA THIS EVENING...WITH ONLY ISOLATED -SHRA EXPECTED FARTHER N
CLOSER TO THE WEAK 850MB TROUGH AS IT REMAINS JUST N OF THE REGION
OVER SE OK/WRN AND CNTRL AR. DID MAINTAIN HIGH CHANCE POPS FOR
AREAS NEAR/S OF THE FRONT THIS EVENING...LOWERING POPS A TAD LATE
AS THE CONVECTION SHOULD WANE ONCE OVERALL FORCING WEAKENS. SHOULD
SEE A WIDE RANGE IN MIN TEMPS OVERNIGHT GIVEN THE SHALLOW NATURE
OF THE POST-FRONTAL AIR MASS...WITH TEMPS POSSIBLY FALLING INTO
THE UPPER 50S OVER SE OK/SW AR.
THE WEAK COLD FRONT IS EXPECTED TO NEAR THE COAST AROUND 12Z
SATURDAY...WITH THE POST-FRONTAL STRATUS HOLDING TOUGH THROUGH THE
DAY. GIVEN THE DEPTH OF THE MOISTURE IN PLACE...DID INSERT SLIGHT
CHANCE POPS AREAWIDE SATURDAY AS ANY WEAK FORCING WILL EASILY
RESULT IN -SHRA DEVELOPMENT...WITH DAYTIME TEMPS ONLY RISING 10
DEGREES OR SO FROM THE MORNING LOWS. THE LOW STRATUS SHOULD BEGIN
TO SLOWLY LIFT SUNDAY...POSSIBLY SCATTERING OUT IN THE AFTERNOON
OVER PORTIONS OF THE REGION. THIS SHOULD RESULT IN MODERATING
TEMPS...ALTHOUGH SFC RIDGING IN PLACE WILL MAINTAIN ABNORMALLY LOW
DEWPOINTS AND COMFORTABLE RH/S FOR THIS TIME OF YEAR. SHOULD BEGIN
TO SEE A RETURN OF HIGHER RH/S BY TUESDAY AS THE BROAD UPPER LEVEL
LOW/TROPICAL WAVE...NOW OVER SRN FL...BEGINS TO SHIFT W ACROSS THE
GULF OF MX THIS WEEKEND AND POSSIBLY IMPACT THE TX COAST.
ATTM...ENOUGH SHEAR ALOFT SHOULD KEEP THIS SYSTEM FROM
INTENSIFYING THIS WEEKEND AND EARLY NEXT WEEK...ALTHOUGH IT WILL
HELP ENHANCE THE SEABREEZE AS IT MOVES INLAND ACROSS SE AND DEEP E
TX/SRN AND CNTRL LA TUESDAY. IN ADDITION...A SHORTWAVE IN THE NW
FLOW ALOFT WILL DROP SE ACROSS THE REGION TUESDAY AS WELL...WHICH
COULD FURTHER ENHANCE FORCING OVER THE SRN SECTIONS OF THE REGION.
HAVE INCREASED POPS TO MID CHANCE S OF I-20 TUESDAY...WITH
CONVECTION DIMINISHING TUESDAY NIGHT/WEDNESDAY AS DRIER AIR ALOFT
MIXES SE IN WAKE OF THIS SHORTWAVE. A DRY NW FLOW LOOKS TO PERSIST
THROUGHOUT THE REMAINDER OF THE WEEK AS UPPER LEVEL RIDGING BUILDS
OVER THE DESERT SW AND THE ROCKIES. TEMPS SHOULD BE NEAR CLIMO
THROUGH THE PERIOD AS WELL.
PRELIMS TO FOLLOW BELOW...
15
&&
.PRELIMINARY POINT TEMPS/POPS...
SHV 64 76 61 85 66 / 30 20 10 10 10
MLU 64 79 61 84 65 / 50 20 10 10 10
DEQ 58 71 57 79 62 / 20 10 10 10 10
TXK 60 73 58 81 63 / 20 20 10 10 10
ELD 61 74 57 81 62 / 30 20 10 10 10
TYR 62 75 61 85 68 / 30 20 10 10 10
GGG 64 76 61 85 66 / 40 20 10 10 10
LFK 67 80 64 88 68 / 60 30 10 10 10
&&
.SHV WATCHES/WARNINGS/ADVISORIES...
AR...NONE.
LA...NONE.
OK...NONE.
TX...NONE.
&&
$$
09
AREA FORECAST DISCUSSION...UPDATED AVIATION
NWS ST LOUIS MO
1127 PM CDT Fri Sep 12 2014
.UPDATE:
Issued at 1027 PM CDT Fri Sep 12 2014
Issued at 620 PM CDT Fri Sep 12 2014
cloud cover continues to slowly recede southeastward across north-
central Missouri. Light to moderate drizzle still continues over
much of central Missouri into southwest and central Illinois.
Light to moderate drizzle will continue over parts of central and
much of east-central - southwest illinois through early Saturday
morning. Cloud cover will slowly recede southward with time. But
will still continue to linger beyond 0900 UTC. Surface winds will
be dimishing to 5 kts after 0600 UTC. temperatures will drop intot
he upper 30s over far northeast Missouri tonight under clear
skies. Should be a fine day on Saturday with partly cloudy skies
and mild tempatures over the region as surface high pressure
builds over the area. Could reach record lows for far northeast
Missouri and again on Sunday morning for northeast through central
Missouri.
Przybylinski
&&
.SHORT TERM: (Through Tonight)
Issued at 236 PM CDT Fri Sep 12 2014
Cloud cover continues to cover the area this afternoon as stratus is
trapped under a low level inversion and mid-high level clouds are
streaming in ahead of a mid level trough. There has been some light
rain associated with the mid-level trough moving across northern
Missouri early this afternoon, but it`s coverage has been limited.
Latest runs of the RAP and HRRR still show some redevelopment of
some light rain over western Missouri this afternoon and this
evening ahead of the upper trough that will move across the CWA this
evening. Then expect clearing of the clouds from north to south
after 06Z as the upper trough moves to the east allowing subsidence
to set in. Drier air will move into the low levels as the inversion
weakens which should allow the low level clouds to move out.
Temperatures should fall close to agreeable MOS guidance for lows
once skies begin to clear with the light northeasterly winds.
Britt
.LONG TERM: (Saturday through Next Friday)
Issued at 236 PM CDT Fri Sep 12 2014
(Saturday through Monday)
Overall, mdls are in good agreement thru this period. Period begins
with a large sfc ridge settling across the region. This ridge will
keep temps around 15 degrees below seasonal average despite ample
insolation. As the ridge retreats, the approaching trof and sfc fnt
will bring another chance for precip to the region late in the
period. Some minor differences in timing are apparent among the mdl
guidance. Will keep PoPs lower except where mdls are in agreement.
(Tuesday through Friday)
Not much change from the prev forecast. Mdls remain in good
agreement overall thru the period with respect to mass fields
anyway. Sfc ridge builds into the region on Tues with precip coming
to an end Mon night. Cool temps will prevail thru mid week, tho not
as cool as this weekend. Mdls differ regarding precip chances for
late Wed into Thurs. The ECMWF is more robust with nocturnal
convection developing along a stationary fnt across the region. The
GFS would suggest height rising with the sfc ridge still holding on
into the area. Have kept PoPs low given the uncertainty forecasting
mesoscale features on day 7.
As for temps, have trended twd the warmer guidance thru the period
given heights over the region.
Tilly
&&
.AVIATION: (For the 06z TAFs through 06z Saturday Night)
Issued at 1119 PM CDT Fri Sep 12 2014
Subsidence and dry air advection at low levels are significantly
eroding the MVFR stratus in place across the region. The clearing
line has already moved through KUIN and KCOU and should reach St.
Louis metro TAF sites during 06-09z. There could be some isolated
spots of fog once clearing occurs, but the combination of drying
low levels and sustained winds AOA 7kts should act to limit any
fog formation to those sheltered areas with higher low-level
moisture. Generally VFR conditions are expected thereafter.
Kanofsky
&&
.CLIMATE:
Issued at 236 PM CDT Fri Sep 12 2014
Record Lows This Weekend:
STL COU UIN
13 43(1975) 33(1902) 33(1902)
14 46(1996) 40(1892) 38(1996)
&&
.LSX WATCHES/WARNINGS/ADVISORIES:
MO...NONE.
IL...NONE.
&&
$$
WFO LSX
AREA FORECAST DISCUSSION
NWS OMAHA/VALLEY NE
1135 PM CDT FRI SEP 12 2014
.UPDATE...
ISSUED AT 924 PM CDT FRI SEP 12 2014
OPTED TO EXPAND THE FROST ADVISORY FOR JUST A COUPLE OF COUNTIES
WHERE TEMPS ARE FORECAST TO DROP TO NEAR 36. MAY ALSO SEE SOME
PATCHY FOG OVERNIGHT. IT MAY BE VERY THIN GROUND FOG...AND MAYBE
MORE STEAM FOG NEAR THE RIVERS AND LAKES. MAY HAVE TO ADD TO THE
FORECAST IF IT BECOMES WIDESPREAD OR DENSE ENOUGH...AND WILL
CONTINUE TO MONITOR THROUGH THE NIGHTTIME. FOG HAD ALREADY
DEVELOPED AT CLARINDA IOWA AND MILLARD...AND LATEST RAP MODEL
SUGGESTS IT COULD EXPAND ESPECIALLY ACROSS WESTERN IOWA WHERE
WINDS WILL PROBABLY REMAIN CALM OVERNIGHT.
&&
.SHORT TERM...(TONIGHT THROUGH MONDAY)
ISSUED AT 319 PM CDT FRI SEP 12 2014
...FIRST FROST OF THE SEASON EXPECTED FOR PARTS OF THE AREA...
THE MAIN CONCERN CONCERN FOR THE SHORT TERM CONTS TO BE WITH THE
COLD WEATHER TONIGHT. WE FEEL THAT MOST LOCATIONS WILL FALL SHORT
OF THE RECORDS LOWS...BUT WITH SKIES CLEARING...WINDS DIMINISHING
THIS EVENING...AND THE SFC HIGH CROSSING THE CWA OVERNIGHT WE ARE
IN FOR THE COLDEST NIGHT YET OF THE EARLY FALL SEASON. GOING
FORECAST LOWS WERE IN GOOD SHAPE AND VERY FEW CHANGES WERE MADE
THERE...BUT WE DID GO AHEAD AND ISSUE A FROST ADVRY FOR PARTS OF
THE AREA THAT WILL LIKELY SEE A COUPLE HOURS OF TEMPERATURES AT OR
BELOW ABOUT 36 DEGREES. RETURN FLOW STARTS TO KICK ON ON SAT BUT
TEMPERATURES WILL REMAIN BELOW NORMAL DESPITE THE MIXING TO 850
MB. LOWS TEMPERATURES WILL BE A BIT WARMER ON SAT NIGHT AHEAD OF
A FRONT THAT WILL START TO WORK INTO THE MID MO RVR VALLEY ON SUN.
ALL MODELS ARE IN PRETTY GOOD AGREEMENT ON THE EVOLUTION OF THE
SENSIBLE WX ASSOCIATED WITH THE FRONT ON SUN/SUN NIGHT ALLOWING
FOR INCREASED CONFIDENCE AND HIGHER POPS. MOISTURE RETURN WILL BE
LIMITED BUT ISENTROPIC LIFT WILL INCREASE DURING THE DAY ON SUN
LEADING TO INCREASING CLOUDS...AND AS LARGE-SCALE FORCING FOR
ASCENT ALSO INCREASES LATE ON SUN AFTN...AS A SHORT-WAVE TROUGH
WORKS THRU SD...WE SHOULD SEE AN INCREASE IN SHRA AND MAYBE AN
ISO TSRA OR TWO. THIS CHANCE WILL CONT TO INCREASE ON SUN NIGHT
AND WE WILL HAVE SOME LIKELY POPS IN THE CNTRL AND SRN CWA. THE
FRONT WILL SHIFT SOUTH OF OUR AREA ON MON ALLOW FOR ANOTHER SHOT
OF COOLER AIR TO MOV IN FOR MON AND MON NIGHT AND WE HAVE LOWERED
HIGHS/LOWS DURING THIS TIME.
.LONG TERM...(MONDAY NIGHT THROUGH FRIDAY)
ISSUED AT 319 PM CDT FRI SEP 12 2014
SENSIBLE WEATHER WILL BE PRETTY QUIET IN THE EXTENDED PERIOD OF
THE FORECAST. THE OVER-ALL PATTERN WILL TRANSITION FROM NORTHWEST
FLOW AND COOL AT THE START OF THE PERIOD TO WESTERLY AND A BIT
WARMER AT THE END. THE PERIOD WILL GENERALLY BE DRY BUT AS THE
UPPER LEVEL FLOW TURNS MORE WEST WE WILL SEE AN INCREASE IN
MOISTURE THAT MAY LEAD TO SOME CHC FOR PRECIP TOWARDS THE END OF
THE PERIOD...ESPECIALLY IN THE NORTHERN CWA CLOSER TO A BOUNDARY.
&&
.AVIATION...(06Z TAFS FOR KOFK...KLNK AND KOMA.)
ISSUED AT 1134 PM CDT FRI SEP 12 2014
VFR CONDITIONS THROUGH THE PERIOD...ALTHOUGH ALL TAF SITES MAY SEE
SOME PATCHY MVFR FOG 09-13Z. LIGHT AND VARIABLE WINDS BECOME SOUTH
AT 12-16 KNOTS BY 16Z...COULD SEE GUSTS UP TO ABOUT 20-22 KNOTS AT
KLNK/KOFK THAT WOULD LINGER THROUGH ABOUT 00Z. THEN WINDS BECOME
AT OR BELOW 10 KNOTS BY 00Z AND BEYOND.
&&
.OAX WATCHES/WARNINGS/ADVISORIES...
NE...FROST ADVISORY FROM 3 AM TO 9 AM CDT SATURDAY FOR NEZ015>018-
030>034-042>045-050-051-065-066-078-088-089.
IA...FROST ADVISORY FROM 3 AM TO 9 AM CDT SATURDAY FOR IAZ043-055-056-
069-079-080-090-091.
&&
$$
UPDATE...DEWALD
SHORT TERM...BOUSTEAD
LONG TERM...BOUSTEAD
AVIATION...DEWALD
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
503 AM EDT SAT SEP 13 2014
.SYNOPSIS...
A FLOOD WATCH HAS BEEN ISSUED FOR SATURDAY AS A STALLED COLD
FRONT CONTINUES UNSETTLED WEATHER ACROSS THE AREA. THIS FRONT WILL
REMAIN IN THE VICINITY ON SUNDAY...BEFORE LIFTING BACK NORTH ON
MONDAY...BUT UNSETTLED WEATHER WILL PERSIST. A STRONGER COLD FRONT WILL
CROSS THE AREA ON TUESDAY...BRINGING COOLER AND DRIER WEATHER FOR
THE LATTER HALF OF NEXT WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 415 AM SATURDAY...A FLOOD WATCH HAS BEEN POSTED FOR THE
ENTIRE ILM CWA...IN EFFECT FROM 6 AM THIS MORNING THROUGH 6 AM
SUNDAY MORNING.
A STALLED FRONTAL BOUNDARY LYING EAST-WEST NEARLY ALONG THE NC-SC
BORDER WILL LIKELY MEANDER BOTH NORTH AND SOUTH THROUGHOUT THE
NEAR TERM PERIOD. INITIALLY...IT MAY TEMPORARILY PUSH NORTHWARD
DUE TO A VIGOROUS UPPER S/W TROF PUSHING FROM THE GREAT LAKES TO
THE NE STATES TODAY. THEN SETTLING BACK TO THE SOUTH
TONIGHT...WITH MODELS HINTING THAT IT MAY DROP SOUTH OF THE ILM
CWA EARLY SUNDAY. PLENTY OF MOISTURE ON EITHER SIDE OF THE FRONTAL
BOUNDARY WITH PWS 2+ INCHES. TO AID PCPN DEVELOPMENT...FORCING...
UVVS...WILL BE PROVIDED BY THE SFC FRONT ITSELF...AND UPPER
DYNAMICS IN THE FORM OF A S/W TROF OR VORT...WILL PROVIDE THE
ADDITIONAL LIFT. NORTH OF THE FRONT WILL OBSERVE OVERRUNNING TYPE
PCPN...IE. STRATIFORM RAINS. HOWEVER...ELEVATED CONVECTION REMAINS
A GOOD POSSIBILITY NORTH OF THE FRONT DUE TO THE AVAILABILITY OF
ELEVATED CAPE...ENERGY. SOUTH OF THE FRONT...THE CHARACTER OF THE
PCPN WILL BE MORE CONVECTIVE. THUS...DIRECTLY ON EITHER SIDE OF
THE FRONT...THE FA WILL BE SUBJECT TO PCPN THAT WILL MOVE ACROSS
ALREADY SATURATED GROUNDS...OVER AND OVER AGAIN...WITH THE END
RESULT LIKELY FLOODING. THUS...A 24 HR FLOOD WATCH HAS BEEN
ISSUED FOR THE ENTIRE ILM CWA...IN EFFECT FROM 6AM SAT-6AM SUN.
VARIOUS MODEL MOS GUIDANCE INDICATES WIDESPREAD 80S FOR MAX TEMPS
TODAY. DEPENDING ON WHICH SIDE OF THE FRONT ONE IS...THE RANGE
WILL RUN FROM THE LOW 80S NORTHERN PORTIONS OF THE ILM CWA TO MID-
UPPER 80S SOUTH OF THE FRONT. THE WIDESPREAD CLOUDS AND PCPN MAY
FURTHER PREVENT TEMPS FROM CLIMBING...ESPECIALLY NORTH OF THE
FRONT WHERE UPPER 70S IS NOT OUT OF THE QUESTION. THE COOLER AND
DRIER AIR BEHIND THE FRONT REMAINS WELL UPSTREAM...FROM VIRGINIA
AND NORTHWARD. THUS EVEN IF TEMPORARY FROPA DOES OCCUR...THIS
AIRMASS WILL NOT BE ABLE TO INFILTRATE THE REGION DURING THIS NEAR
TERM PERIOD.
&&
.SHORT TERM /SUNDAY THROUGH MONDAY NIGHT/...
AS OF 300 AM SATURDAY...AN EXPANDING TROUGH AND A PERSISTENT RIDGE
WILL ENGAGE IN BATTLE OVERHEAD THROUGH EARLY NEXT WEEK FOR POSITION
OVER THE CAROLINAS. ALMOST LIKE THE OLD CHILDHOOD GAME OF "RED
ROVER"...EACH FEATURE WILL TRY TO BREAK THROUGH THE OTHER...BUT THE
RIDGE WILL CALL THE TROUGH OVER ONE TOO MANY TIMES...EARNING THE
TROUGH A VICTORY...DISPLACING THE RIDGE BY MONDAY NIGHT. THIS
FORCES THE COLD FRONT BELOW TO BECOME NEARLY STATIONARY SUNDAY AND
MONDAY...WAVERING BACK AND FORTH ACROSS THE AREA...CONTINUING THE
UNSETTLED WEATHER PATTERN.
SURFACE FRONT WILL BE ALONG THE SOUTHERN TIER...OR JUST SOUTH...OF
THE CWA DURING SUNDAY BEFORE SLOWLY LIFTING NORTH AGAIN ON MONDAY.
WHILE INSTABILITY WILL BE LIMITED DUE TO WIDESPREAD CLOUD
COVER...AND UPPER SUPPORT WILL REMAIN MINIMAL...PERSISTENT MOIST
FLOW ATOP THE FRONT COMBINED WITH SURFACE CONVERGENCE ALONG IT (AND
RESIDUAL BOUNDARIES) IN A VERY MOIST COLUMN WILL PRODUCE PERIODS OF
RAIN/TSTMS SUNDAY AND MONDAY. BEST PRECIP CHANCES MAY BE IN THE
SOUTHERN AND WESTERN ZONES SUNDAY AND THIS IS WHERE THE HIGHEST QPF
IS EXPECTED...BUT ALL AREAS WILL LIKELY SEE SHOWERS AND STORMS. A
BRIEF RESPITE IN CONVECTIVE COVERAGE WILL OCCUR WITH LOSS OF HEATING
SUNDAY NIGHT...BEFORE MORE SCATTERED CONVECTION DEVELOPS MONDAY AS
THE FRONT LIFTS TO THE NORTH PRODUCING A BRIEF PERIOD OF WAA AND
SUMMER-LIKE CONVECTION. THIS WILL BE SHORT LIVED HOWEVER...AS THIS
FRONT WILL RETURN BACK TO THE SOUTHEAST AS A COLD FRONT BENEATH A
STRONG VORTICITY IMPULSE MOVING TO THE NORTH EITHER VERY LATE MONDAY
NIGHT...OR JUST BEYOND THIS PERIOD. ANOTHER ROUND OF HEAVIER PRECIP
MAY ACCOMPANY THIS FRONT LATE MONDAY HOWEVER...AND CANNOT AT ANY
TIME FORECAST POP BELOW CHC THROUGH THE PERIOD...WITH HIGHEST
OCCURRING SUNDAY AND THEN AGAIN LATE MONDAY.
HIGHS SUNDAY WILL BE SEVERAL DEGREES BELOW NORMAL THANKS TO
CLOUDS...RAIN...AND COOL NORTHERLY SURFACE FLOW...WITH MAX TEMPS
EXPECTED TO REACH ONLY THE MID 70S FAR NW...TO MID 80S NEAR THE
SOUTH SANTEE RIVER. THE AFOREMENTIONED WAA WILL DRIVE HIGHS INTO THE
LOW/MID 80S CWA-WIDE ON MONDAY. LOWS SUNDAY NIGHT WILL DROP TO
NEAR-NORMAL LEVELS OF THE MID 60S...BUT WILL BE SEVERAL DEGREES
WARMER MONDAY NIGHT AHEAD OF THE NEXT COLD FRONT.
&&
.LONG TERM /TUESDAY THROUGH FRIDAY/...
AS OF 300 SATURDAY...STRONG COLD FRONT WILL PUSH ACROSS THE AREA ON
TUESDAY...USHERING IN COOL CANADIAN AIR FOR MOST OF THE UPCOMING
WEEK.
STRONG VORTICITY IMPULSE SPAWNING A SURFACE LOW PRESSURE WILL BE
RACING EAST WELL NORTH OF THE AREA...BUT A STRONG COLD FRONT BEHIND
THIS WILL DRAG ACROSS THE CWA DURING TUESDAY. A PERIOD OF UNSETTLED
WEATHER IS EXPECTED TUESDAY WITH SHOWERS AND THUNDERSTORMS...BUT
THIS FRONT SHOULD PUSH OFFSHORE BY WEDNESDAY AS A DEEP UPPER TROUGH
DIVES INTO THE EAST. THEREAFTER...GUIDANCE CONTINUES TO DIFFER ON
HOW FAR OFFSHORE THIS FRONT WILL STALL...WITH THE GFS CONTINUING TO
INDICATE THAT IT WILL BE JUST OFFSHORE AND CONTINUE UNSETTLED
CONDITIONS LOCALLY. THE ECMWF...WHICH IS PREFERRED...PUSHES THIS
FRONT WELL OFF THE COAST...WHICH SEEMS ACCURATE BASED OFF THE
STRENGTH OF THE UPPER TROUGH AND SINCE WE HAVE HAD SEVERAL FROPAS
ALREADY THIS YEAR.
USING THE ECMWF AS A GUIDE...WED-FRI WILL FEATURE
DRYING CONDITIONS AND TEMPS AROUND 5 DEGREES BELOW CLIMO THANKS TO
THE CANADIAN ORIGIN OF THE SURFACE HIGH RIDGING DOWN THE COAST. IN
ADDITION...IT APPEARS THE AREA WILL SEE SUNSHINE FOR THE FIRST TIME
IN SEVERAL DAYS BY WEDNESDAY. HOWEVER...MUST NOTE THE PERSISTENCE OF
THE GFS WHICH KEEPS THE FRONT JUST OFF THE COAST AND DEVELOPS A LOW
PRESSURE SYSTEM ALONG THE TAIL END OF THE BOUNDARY. THIS WOULD KEEP
UNSETTLED CONDITIONS ACROSS THE AREA...ESPECIALLY NEAR THE
COAST...WITH MORE WET WEATHER POSSIBLE LATE IN THE WEEK.
WILL KEEP INHERITED LOW-CHC/SCHC POP FOR POTENTIAL...BUT WITH A
SLIGHT DECREASE IN SPECIFIC VALUES TO ACCOUNT FOR THE MUCH DRIER
ECMWF.
&&
.AVIATION /08Z SATURDAY THROUGH WEDNESDAY/...
AS OF 06Z...STRATIFORM LIGHT RAIN NEAR KILM SHOULD DISSIPATE
OVER THE NEXT SEVERAL HOURS...ALTHOUGH THE HRRR MODEL SUGGESTS
ISOLATED CONVECTIVE SHOWERS WILL RE-DEVELOP EARLY THIS MORNING
ACROSS THE AREA. EXPECT THICK MID/UPPER CLOUD COVER THROUGH THE TAF
VALID PERIOD WITH COPIOUS AMOUNTS OF LOW LEVEL MOISTURE. IFR/LIFR
CONDITIONS WILL DEVELOP THIS MORNING KLBT/KILM/FLO WITH HIGHEST
CONFIDENCE AT KLBT/KILM WHICH IS NEAREST A STATIONARY FRONT.
KCRE/KMYR ARE MORE LIKELY TO EXPERIENCE MVFR CONDITIONS THIS
MORNING. ANY IFR IMPROVES TO MVFR FAIRLY QUICKLY AFTER SUNRISE WITH
VFR DEVELOPING MID-LATE MORNING. CLOUD COVER SHOULD INITIALLY
INHIBIT HEATING AND LIFT SO THINK WORSE CASE VCSH COASTAL TERMINALS
IN THE MORNING HOURS. BY AFTERNOON THUNDERSTORM POTENTIAL SHOULD BE
GREATEST AT KLBT. THIS POTENTIAL SHOULD SHIFT SE-E TO KFLO AND THE
THE COASTAL TERMINALS IN THE LATE AFTERNOON/EARLY EVENING.
EXTENDED OUTLOOK...A CHANCE OF SHOWERS WITH MAINLY AFTERNOON
THUNDERSTORMS/TEMPO MVFR THROUGH TUESDAY.
&&
.MARINE...
NEAR TERM/THROUGH TONIGHT/...
AS OF 415 AM SATURDAY...WINDS AND TO A LESSER DEGREE SIGNIFICANT
SEAS...WILL BE GOVERNED BY THE MEANDERING FRONTAL BOUNDARY DURING
THIS PERIOD. THIS MEANS...WATERS NORTH OF THE FRONT WILL OBSERVE
NE-E WINDS...AND SOUTH OF THE FRONT THE WATERS WILL SEE SE-SSW
WINDS. THE SFC PG REMAINS LOOSE FOR THE MOST PART RESULTING WITH
WIND SPEEDS AROUND 10 KT. HOWEVER...DEPENDING ON YOUR LOCATION
BEHIND THE FRONT...THE NE-E WINDS THAT OCCUR COULD PRODUCE A
MINI-SURGE WITH SPEEDS UP TO 15 KT. SIGNIFICANT SEAS WILL REMAIN
DOCILE...AROUND 2 FT. THE MINI NE-E SURGE BEHIND THE FRONT COULD
PRODUCE SIG. SEAS UP TO 3 FT. AVERAGE PERIODS WILL RUN 4 TO 5
SECONDS.
SHORT TERM /SUNDAY THROUGH MONDAY NIGHT/...
AS OF 300 AM SATURDAY...COLD FRONT SOUTH OF THE WATERS TO START THE
PERIOD WILL REMAIN NEARLY STATIONARY SUNDAY...BEFORE LIFTING BACK TO
THE NORTH AS A WARM FRONT MONDAY. THIS DRIVES NE WINDS ALL SUNDAY
AND INTO MONDAY...BEFORE VEERING TO BECOME S/SE LATE ON MONDAY.
SPEEDS WILL BE 5-10 KTS REGARDLESS OF DIRECTION. A COLD FRONT WILL
APPROACH AT THE VERY END OF THE SHORT TERM WITH WINDS BEGINNING TO
VEER TO THE WEST LATE MONDAY NIGHT. SEAS WILL BE 1-3 FT THROUGH THE
PERIOD...WITH A NE WIND WAVE PREDOMINANT ON SUNDAY...BECOMING
SOUTHERLY DURING MONDAY.
LONG TERM /TUESDAY THROUGH WEDNESDAY/...
AS OF 300 AM SATURDAY...THE BEGINNING OF AN EXTENDED PERIOD OF POOR
MARINE CONDITIONS EXPECTED TUESDAY AS A COLD FRONT CROSSES THE
WATERS. ALTHOUGH WINDS TUESDAY WILL BE PRETTY LIGHT...5-10 KTS WITH
SEVERAL VEERING WIND DIRECTIONS...THE CONFUSED SPECTRUM WILL COMBINE
WITH THE SLOWLY AMPLIFYING LONG PERIOD 13-14 SEC SE SWELL ASSOCIATED
WITH TROPICAL STORM EDOUARD MOVING THROUGH THE CENTRAL ATLANTIC...TO
DRIVE INCREASING WAVE HEIGHTS. ADDITIONALLY...A NE SURGE WILL BEGIN
TUESDAY NIGHT BEHIND THIS BOUNDARY...WITH NE WINDS RISING TO AROUND
15 KTS ON WEDNESDAY.
THE COMBINATION OF THE LONG-PERIOD SWELL AND INCREASING WINDS WILL
DRIVE WAVE HEIGHTS FROM 2-4 FT TUESDAY TO 4-6 FT WEDNESDAY...AND A
SMALL CRAFT ADVISORY WILL LIKELY BE NEEDED BEGINNING WEDNESDAY.
ALTHOUGH IT IS BEYOND THIS PERIOD...IT APPEARS WEDNESDAY COULD BE
THE FIRST OF SEVERAL CONSECUTIVE DAYS WITH HEADLINES NEEDED ACROSS
THE COASTAL WATERS.
&&
.ILM WATCHES/WARNINGS/ADVISORIES...
SC...FLOOD WATCH THROUGH LATE TONIGHT FOR SCZ017-023-024-032-033-
039-053>056.
NC...FLOOD WATCH THROUGH LATE TONIGHT FOR NCZ087-096-099-105>110.
MARINE...NONE.
&&
$$
SYNOPSIS...JDW
NEAR TERM...DCH
SHORT TERM...JDW
LONG TERM...JDW
AVIATION...DCH/MRR
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
338 AM EDT SAT SEP 13 2014
.SYNOPSIS...
A FLOOD WATCH HAS BEEN ISSUED FOR SATURDAY AS A STALLED COLD
FRONT CONTINUES UNSETTLED WEATHER ACROSS THE AREA. THIS FRONT WILL
REMAIN IN THE VICINITY ON SUNDAY...BEFORE LIFTING BACK NORTH ON
MONDAY...BUT UNSETTLED WEATHER WILL PERSIST. A STRONGER COLD FRONT WILL
CROSS THE AREA ON TUESDAY...BRINGING COOLER AND DRIER WEATHER FOR
THE LATTER HALF OF NEXT WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 10:30 PM FRIDAY...ALTHOUGH MOST OF THE FORECAST AREA THIS
EVENING SAW STRATIFORM RAIN OF GRADUALLY DIMINISHING EXTENT...THE
CAPE FEAR REGION AND WILMINGTON IN PARTICULAR EXPERIENCED A HEAVY
RAIN EVENT COMPLETE WITH LOCALIZED FLOODING. IT APPEARS THAT A
SERIES OF UNFORTUNATELY PLACED BOUNDARY COLLISIONS AND A JUICY
AIR-MASS WERE RESPONSIBLE. LIGHT TO MODERATE RAIN IS STILL
BLANKETING NEW HANOVER COUNTY AND A FLOOD WARNING IS OUT FOR THAT
AREA. GIVEN P/W VALUES IN EXCESS OF 2 INCHES SHOWER ACTIVITY AREA-
WIDE CONTINUES TO BE A POSSIBILITY...ESPECIALLY GIVEN THE
PROXIMITY OF THE COLD FRONT...WHICH SEEMS TO NOW EXTEND ACROSS THE
NORTHERN HALF OF THE FORECAST AREA WITH A FRONTAL WAVE NOW PLACED
OVER THE CAPE FEAR REGION. THIS ALSO NO DOUBT ENHANCED OUR RECENT
BOUT OF HEAVY RAIN.
&&
.SHORT TERM /SUNDAY THROUGH MONDAY NIGHT/...
AS OF 300 AM SATURDAY...AN EXPANDING TROUGH AND A PERSISTENT RIDGE
WILL ENGAGE IN BATTLE OVERHEAD THROUGH EARLY NEXT WEEK FOR POSITION
OVER THE CAROLINAS. ALMOST LIKE THE OLD CHILDHOOD GAME OF "RED
ROVER"...EACH FEATURE WILL TRY TO BREAK THROUGH THE OTHER...BUT THE
RIDGE WILL CALL THE TROUGH OVER ONE TOO MANY TIMES...EARNING THE
TROUGH A VICTORY...DISPLACING THE RIDGE BY MONDAY NIGHT. THIS
FORCES THE COLD FRONT BELOW TO BECOME NEARLY STATIONARY SUNDAY AND
MONDAY...WAVERING BACK AND FORTH ACROSS THE AREA...CONTINUING THE
UNSETTLED WEATHER PATTERN.
SURFACE FRONT WILL BE ALONG THE SOUTHERN TIER...OR JUST SOUTH...OF
THE CWA DURING SUNDAY BEFORE SLOWLY LIFTING NORTH AGAIN ON MONDAY.
WHILE INSTABILITY WILL BE LIMITED DUE TO WIDESPREAD CLOUD
COVER...AND UPPER SUPPORT WILL REMAIN MINIMAL...PERSISTENT MOIST
FLOW ATOP THE FRONT COMBINED WITH SURFACE CONVERGENCE ALONG IT (AND
RESIDUAL BOUNDARIES) IN A VERY MOIST COLUMN WILL PRODUCE PERIODS OF
RAIN/TSTMS SUNDAY AND MONDAY. BEST PRECIP CHANCES MAY BE IN THE
SOUTHERN AND WESTERN ZONES SUNDAY AND THIS IS WHERE THE HIGHEST QPF
IS EXPECTED...BUT ALL AREAS WILL LIKELY SEE SHOWERS AND STORMS. A
BRIEF RESPITE IN CONVECTIVE COVERAGE WILL OCCUR WITH LOSS OF HEATING
SUNDAY NIGHT...BEFORE MORE SCATTERED CONVECTION DEVELOPS MONDAY AS
THE FRONT LIFTS TO THE NORTH PRODUCING A BRIEF PERIOD OF WAA AND
SUMMER-LIKE CONVECTION. THIS WILL BE SHORT LIVED HOWEVER...AS THIS
FRONT WILL RETURN BACK TO THE SOUTHEAST AS A COLD FRONT BENEATH A
STRONG VORTICITY IMPULSE MOVING TO THE NORTH EITHER VERY LATE MONDAY
NIGHT...OR JUST BEYOND THIS PERIOD. ANOTHER ROUND OF HEAVIER PRECIP
MAY ACCOMPANY THIS FRONT LATE MONDAY HOWEVER...AND CANNOT AT ANY
TIME FORECAST POP BELOW CHC THROUGH THE PERIOD...WITH HIGHEST
OCCURRING SUNDAY AND THEN AGAIN LATE MONDAY.
HIGHS SUNDAY WILL BE SEVERAL DEGREES BELOW NORMAL THANKS TO
CLOUDS...RAIN...AND COOL NORTHERLY SURFACE FLOW...WITH MAX TEMPS
EXPECTED TO REACH ONLY THE MID 70S FAR NW...TO MID 80S NEAR THE
SOUTH SANTEE RIVER. THE AFOREMENTIONED WAA WILL DRIVE HIGHS INTO THE
LOW/MID 80S CWA-WIDE ON MONDAY. LOWS SUNDAY NIGHT WILL DROP TO
NEAR-NORMAL LEVELS OF THE MID 60S...BUT WILL BE SEVERAL DEGREES
WARMER MONDAY NIGHT AHEAD OF THE NEXT COLD FRONT.
&&
.LONG TERM /TUESDAY THROUGH FRIDAY/...
AS OF 300 SATURDAY...STRONG COLD FRONT WILL PUSH ACROSS THE AREA ON
TUESDAY...USHERING IN COOL CANADIAN AIR FOR MOST OF THE UPCOMING
WEEK.
STRONG VORTICITY IMPULSE SPAWNING A SURFACE LOW PRESSURE WILL BE
RACING EAST WELL NORTH OF THE AREA...BUT A STRONG COLD FRONT BEHIND
THIS WILL DRAG ACROSS THE CWA DURING TUESDAY. A PERIOD OF UNSETTLED
WEATHER IS EXPECTED TUESDAY WITH SHOWERS AND THUNDERSTORMS...BUT
THIS FRONT SHOULD PUSH OFFSHORE BY WEDNESDAY AS A DEEP UPPER TROUGH
DIVES INTO THE EAST. THEREAFTER...GUIDANCE CONTINUES TO DIFFER ON
HOW FAR OFFSHORE THIS FRONT WILL STALL...WITH THE GFS CONTINUING TO
INDICATE THAT IT WILL BE JUST OFFSHORE AND CONTINUE UNSETTLED
CONDITIONS LOCALLY. THE ECMWF...WHICH IS PREFERRED...PUSHES THIS
FRONT WELL OFF THE COAST...WHICH SEEMS ACCURATE BASED OFF THE
STRENGTH OF THE UPPER TROUGH AND SINCE WE HAVE HAD SEVERAL FROPAS
ALREADY THIS YEAR.
USING THE ECMWF AS A GUIDE...WED-FRI WILL FEATURE
DRYING CONDITIONS AND TEMPS AROUND 5 DEGREES BELOW CLIMO THANKS TO
THE CANADIAN ORIGIN OF THE SURFACE HIGH RIDGING DOWN THE COAST. IN
ADDITION...IT APPEARS THE AREA WILL SEE SUNSHINE FOR THE FIRST TIME
IN SEVERAL DAYS BY WEDNESDAY. HOWEVER...MUST NOTE THE PERSISTENCE OF
THE GFS WHICH KEEPS THE FRONT JUST OFF THE COAST AND DEVELOPS A LOW
PRESSURE SYSTEM ALONG THE TAIL END OF THE BOUNDARY. THIS WOULD KEEP
UNSETTLED CONDITIONS ACROSS THE AREA...ESPECIALLY NEAR THE
COAST...WITH MORE WET WEATHER POSSIBLE LATE IN THE WEEK.
WILL KEEP INHERITED LOW-CHC/SCHC POP FOR POTENTIAL...BUT WITH A
SLIGHT DECREASE IN SPECIFIC VALUES TO ACCOUNT FOR THE MUCH DRIER
ECMWF.
&&
.AVIATION /08Z SATURDAY THROUGH WEDNESDAY/...
AS OF 06Z...STRATIFORM LIGHT RAIN NEAR KILM SHOULD DISSIPATE
OVER THE NEXT SEVERAL HOURS...ALTHOUGH THE HRRR MODEL SUGGESTS
ISOLATED CONVECTIVE SHOWERS WILL RE-DEVELOP EARLY THIS MORNING
ACROSS THE AREA. EXPECT THICK MID/UPPER CLOUD COVER THROUGH THE TAF
VALID PERIOD WITH COPIOUS AMOUNTS OF LOW LEVEL MOISTURE. IFR/LIFR
CONDITIONS WILL DEVELOP THIS MORNING KLBT/KILM/FLO WITH HIGHEST
CONFIDENCE AT KLBT/KILM WHICH IS NEAREST A STATIONARY FRONT.
KCRE/KMYR ARE MORE LIKELY TO EXPERIENCE MVFR CONDITIONS THIS
MORNING. ANY IFR IMPROVES TO MVFR FAIRLY QUICKLY AFTER SUNRISE WITH
VFR DEVELOPING MID-LATE MORNING. CLOUD COVER SHOULD INITIALLY
INHIBIT HEATING AND LIFT SO THINK WORSE CASE VCSH COASTAL TERMINALS
IN THE MORNING HOURS. BY AFTERNOON THUNDERSTORM POTENTIAL SHOULD BE
GREATEST AT KLBT. THIS POTENTIAL SHOULD SHIFT SE-E TO KFLO AND THE
THE COASTAL TERMINALS IN THE LATE AFTERNOON/EARLY EVENING.
EXTENDED OUTLOOK...A CHANCE OF SHOWERS WITH MAINLY AFTERNOON
THUNDERSTORMS/TEMPO MVFR THROUGH TUESDAY.
&&
.MARINE...
NEAR TERM/THROUGH TONIGHT/...
AS OF 10:30 PM FRIDAY...LIGHT AND VARIABLE WINDS WITH 2 FT SEAS
CONTINUE ACROSS THE WATERS THIS EVENING. FORECAST REMAINS
UNCHANGED. PREVIOUS DISCUSSION FOLLOWS:
OUTSIDE OF TSTMS NO REAL PROBLEMS EXPECTED ON THE WATERS WITH
LIGHT WINDS OVERALL AND SEAS 2 FEET OR LESS...AS A WEAK FRONTAL
BOUNDARY REMAINS IN VICINITY OF THE AREA. MOST STORMS SHOULD STAY
OVER LAND BUT TONIGHT CELLS MAY BEGIN TO FAVOR THE 0-20 NM WATERS.
SEAS AROUND 2 FEET IN A MIX OF SE WAVES 1-1.5 FT EVERY 8-9 SECONDS
AND S WAVES 0.5-1 FT EVERY 3-4 SECONDS. WITHIN TSTMS WINDS AND
SEAS WILL BE LOCALLY AND SIGNIFICANTLY HIGHER.
SHORT TERM /SUNDAY THROUGH MONDAY NIGHT/...
AS OF 300 AM SATURDAY...COLD FRONT SOUTH OF THE WATERS TO START THE
PERIOD WILL REMAIN NEARLY STATIONARY SUNDAY...BEFORE LIFTING BACK TO
THE NORTH AS A WARM FRONT MONDAY. THIS DRIVES NE WINDS ALL SUNDAY
AND INTO MONDAY...BEFORE VEERING TO BECOME S/SE LATE ON MONDAY.
SPEEDS WILL BE 5-10 KTS REGARDLESS OF DIRECTION. A COLD FRONT WILL
APPROACH AT THE VERY END OF THE SHORT TERM WITH WINDS BEGINNING TO
VEER TO THE WEST LATE MONDAY NIGHT. SEAS WILL BE 1-3 FT THROUGH THE
PERIOD...WITH A NE WIND WAVE PREDOMINANT ON SUNDAY...BECOMING
SOUTHERLY DURING MONDAY.
LONG TERM /TUESDAY THROUGH WEDNESDAY/...
AS OF 300 AM SATURDAY...THE BEGINNING OF AN EXTENDED PERIOD OF POOR
MARINE CONDITIONS EXPECTED TUESDAY AS A COLD FRONT CROSSES THE
WATERS. ALTHOUGH WINDS TUESDAY WILL BE PRETTY LIGHT...5-10 KTS WITH
SEVERAL VEERING WIND DIRECTIONS...THE CONFUSED SPECTRUM WILL COMBINE
WITH THE SLOWLY AMPLIFYING LONG PERIOD 13-14 SEC SE SWELL ASSOCIATED
WITH TROPICAL STORM EDOUARD MOVING THROUGH THE CENTRAL ATLANTIC...TO
DRIVE INCREASING WAVE HEIGHTS. ADDITIONALLY...A NE SURGE WILL BEGIN
TUESDAY NIGHT BEHIND THIS BOUNDARY...WITH NE WINDS RISING TO AROUND
15 KTS ON WEDNESDAY.
THE COMBINATION OF THE LONG-PERIOD SWELL AND INCREASING WINDS WILL
DRIVE WAVE HEIGHTS FROM 2-4 FT TUESDAY TO 4-6 FT WEDNESDAY...AND A
SMALL CRAFT ADVISORY WILL LIKELY BE NEEDED BEGINNING WEDNESDAY.
ALTHOUGH IT IS BEYOND THIS PERIOD...IT APPEARS WEDNESDAY COULD BE
THE FIRST OF SEVERAL CONSECUTIVE DAYS WITH HEADLINES NEEDED ACROSS
THE COASTAL WATERS.
&&
.ILM WATCHES/WARNINGS/ADVISORIES...
SC...FLOOD WATCH THROUGH LATE TONIGHT FOR SCZ017-023-024-032-033-
039-053>056.
NC...FLOOD WATCH THROUGH LATE TONIGHT FOR NCZ087-096-099-105>110.
MARINE...NONE.
&&
$$
SYNOPSIS...JDW
NEAR TERM...DCH/REK
SHORT TERM...JDW
LONG TERM...JDW
AVIATION...DCH/MRR
MARINE...DCH/REK/JDW
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
157 AM EDT SAT SEP 13 2014
.SYNOPSIS...
A COLD FRONT WILL BRING UNSETTLED WEATHER THROUGH THE WEEKEND. THE
FRONT WILL WEAKEN ON MONDAY BUT MOISTURE WILL LINGER FOR A
SCATTERING OF SHOWERS ON MONDAY. ANOTHER COLD FRONT SHOULD AFFECT
THE REGION ON WEDNESDAY.
&&
.NEAR TERM /UNTIL 6 AM THIS MORNING/...
AS OF 10:30 PM FRIDAY...ALTHOUGH MOST OF THE FORECAST AREA THIS
EVENING SAW STRATIFORM RAIN OF GRADUALLY DIMINISHING EXTENT...THE
CAPE FEAR REGION AND WILMINGTON IN PARTICULAR EXPERIENCED A HEAVY
RAIN EVENT COMPLETE WITH LOCALIZED FLOODING. IT APPEARS THAT A
SERIES OF UNFORTUNATELY PLACED BOUNDARY COLLISIONS AND A JUICY
AIR-MASS WERE RESPONSIBLE. LIGHT TO MODERATE RAIN IS STILL
BLANKETING NEW HANOVER COUNTY AND A FLOOD WARNING IS OUT FOR THAT
AREA. GIVEN P/W VALUES IN EXCESS OF 2 INCHES SHOWER ACTIVITY AREA-
WIDE CONTINUES TO BE A POSSIBILITY...ESPECIALLY GIVEN THE
PROXIMITY OF THE COLD FRONT...WHICH SEEMS TO NOW EXTEND ACROSS THE
NORTHERN HALF OF THE FORECAST AREA WITH A FRONTAL WAVE NOW PLACED
OVER THE CAPE FEAR REGION. THIS ALSO NO DOUBT ENHANCED OUR RECENT
BOUT OF HEAVY RAIN.
&&
.SHORT TERM /6 AM THIS MORNING THROUGH SUNDAY NIGHT/...
AS OF 3 PM FRIDAY...ANOTHER FAIRLY UNSETTLED AFTERNOON IN STORE FOR
THE REGION SATURDAY AS COLD FRONT ENTERS THE COASTAL PLAIN IN THE
PRESENCE OF FAIRLY DEEP TROPICAL MOISTURE. THE MOST WIDESPREAD
COVERAGE WILL BE OVER NWRN ZONES WHICH WILL BE MOST PROXIMAL TO THE
BOUNDARY...PERHAPS RADAR COVERAGE NOT UNLIKE THAT OF THIS AFTERNOON.
WITH A MORE CLOUDY START COMPARED TO TODAY AFTERNOON TEMPERATURES
WILL NOT GROW AS HOT AND TEND TO BE QUITE SEASONABLE. PRECIPITABLE
WATER REMAINS ABOVE 2 INCHES WHILE STORM MOTION REMAINS BELOW 5KT SO
CHANCE FOR HEAVY DOWNPOURS REMAINS INTACT. RAIN CHANCES WILL HAVE A
HARD TIME DIPPING MUCH LOWER THAN LOW END CHANCE RANGE SATURDAY
NIGHT AS THE FRONT MOVES ATOP OF THE FORECAST AREA...ALTHOUGH THE
LOSS OF DAYTIME HEATING SHOULD DIMINISH THEIR INTENSITY AND THE
HEAVY RAIN THREAT. WE WIND UP ON THE OTHER SIDE OF THE FRONT ON
SUNDAY AS IT REMAINS NEARLY STALLED TO OUR SOUTH AND EAST. RAIN
CHANCES WILL BE SHIFTED SOUTH AND EAST ACCORDINGLY AND THE HEAVY
RAIN THREAT WILL BE RELATIVELY MITIGATED. SUNDAY AFTERNOON MAY OFFER
UP A RANGE OF HIGH TEMPERATURES FROM NORTH TO SOUTH FROM THE UPPER
70S TO THE MID 80S.
&&
.LONG TERM /MONDAY THROUGH FRIDAY/...
AS OF 3 PM FRIDAY...WEAKENING FRONT STALLED IN THE AREA AT THE START
OF THE PERIOD AND DEEP TROPICAL MOISTURE ENSURE THE FIRST HALF OF
NEXT WEEK REMAIN UNSETTLED. PRECIPITABLE WATER VALUES AROUND 2
INCHES MON AND TUE IN A MODERATELY UNSTABLE AIRMASS SHOULD LEAD TO
SHOWER AND THUNDERSTORM DEVELOPMENT. PLAN TO CARRY CHC POP WITH A
DIURNAL DISTRIBUTION. THE LACK OF FORCING ALOFT SHOULD LEAD TO A
DECREASE IN COVERAGE/ACTIVITY OVERNIGHT BUT DO NOT THINK STORMS WILL
COMPLETELY DISSIPATE. STORM MOTIONS WILL REMAIN 10 KT OR LESS WHICH
WILL MAINTAIN FLOODING POTENTIAL.
A STRONGER COLD FRONT WILL DROP IN FROM THE NORTHWEST MID WEEK. THIS
FRONT HAS A MORE DEFINED TROUGH BEHIND IT WHICH WILL PUSH THE
BOUNDARY SOUTH OF THE AREA BY THE END OF THE WEEK. HOWEVER THERE IS
STILL SOME UNCERTAINTY AS TO HOW FAR SOUTH THIS FRONT MOVES BEFORE
STALLING. ECMWF HAS THE FRONT FARTHER SOUTH...SO DOES WPC...WHILE
THE GFS KEEPS THE FRONT CLOSER TO THE CAROLINAS. BOTH MEDIUM RANGE
SOLUTIONS DEVELOP A WEAK LOW ON THE FRONT AND LIFT IT NORTH...THOUGH
TIMING IS DIFFERENT. ECMWF SOLUTION WOULD PRODUCE SLIGHT CHC TO LOW
CHC OF PRECIP THROUGH THU...MAINLY ALONG THE COAST...WITH DRYING
FRI. GFS IS WETTER WITH HIGH CHC TO LIKELY POP THROUGH THE END OF
THE PERIOD FOR MUCH OF THE FORECAST AREA. PREVIOUS FORECASTS HAVE
BEEN IN LINE WITH THE DRIER ECMWF/WPC SOLUTION AND AT THIS POINT CAN
SEE NO REASON TO MAKE A CHANGE. CONFIDENCE REMAINS LOW SO
SIGNIFICANT CHANGES IN LATER FORECASTS IS STILL A POSSIBILITY.
TEMPERATURE RANGES EARLY IN THE PERIOD WILL BE ON THE NARROW END
WITH CLOUD COVER AND PRECIP KEEPING HIGHS NEAR TO SLIGHTLY BELOW
CLIMO BUT HELPING HOLD LOWS SEVERAL DEGREES ABOVE CLIMO. PASSAGE OF
FRONT MID WEEK WILL BRING BELOW CLIMO TEMPS FOR THE END OF THE WEEK.
&&
.AVIATION /06Z SATURDAY THROUGH WEDNESDAY/...
AS OF 06Z...STRATIFORM LIGHT RAIN NEAR KILM SHOULD DISSIPATE
OVER THE NEXT SEVERAL HOURS...ALTHOUGH THE HRRR MODEL SUGGESTS
ISOLATED CONVECTIVE SHOWERS WILL RE-DEVELOP EARLY THIS MORNING
ACROSS THE AREA. EXPECT THICK MID/UPPER CLOUD COVER THROUGH THE TAF
VALID PERIOD WITH COPIOUS AMOUNTS OF LOW LEVEL MOISTURE. IFR/LIFR
CONDITIONS WILL DEVELOP THIS MORNING KLBT/KILM/FLO WITH HIGHEST
CONFIDENCE AT KLBT/KILM WHICH IS NEAREST A STATIONARY FRONT.
KCRE/KMYR ARE MORE LIKELY TO EXPERIENCE MVFR CONDITIONS THIS
MORNING. ANY IFR IMPROVES TO MVFR FAIRLY QUICKLY AFTER SUNRISE WITH
VFR DEVELOPING MID-LATE MORNING. CLOUD COVER SHOULD INITIALLY
INHIBIT HEATING AND LIFT SO THINK WORSE CASE VCSH COASTAL TERMINALS
IN THE MORNING HOURS. BY AFTERNOON THUNDERSTORM POTENTIAL SHOULD BE
GREATEST AT KLBT. THIS POTENTIAL SHOULD SHIFT SE-E TO KFLO AND THE
THE COASTAL TERMINALS IN THE LATE AFTERNOON/EARLY EVENING.
EXTENDED OUTLOOK...A CHANCE OF SHOWERS WITH MAINLY AFTERNOON
THUNDERSTORMS/TEMPO MVFR THROUGH TUESDAY.
&&
.MARINE...
NEAR TERM/THROUGH TONIGHT/...
AS OF 10:30 PM FRIDAY...LIGHT AND VARIABLE WINDS WITH 2 FT SEAS
CONTINUE ACROSS THE WATERS THIS EVENING. FORECAST REMAINS
UNCHANGED. PREVIOUS DISCUSSION FOLLOWS:
OUTSIDE OF TSTMS NO REAL PROBLEMS EXPECTED ON THE WATERS WITH
LIGHT WINDS OVERALL AND SEAS 2 FEET OR LESS...AS A WEAK FRONTAL
BOUNDARY REMAINS IN VICINITY OF THE AREA. MOST STORMS SHOULD STAY
OVER LAND BUT TONIGHT CELLS MAY BEGIN TO FAVOR THE 0-20 NM WATERS.
SEAS AROUND 2 FEET IN A MIX OF SE WAVES 1-1.5 FT EVERY 8-9 SECONDS
AND S WAVES 0.5-1 FT EVERY 3-4 SECONDS. WITHIN TSTMS WINDS AND
SEAS WILL BE LOCALLY AND SIGNIFICANTLY HIGHER.
SHORT TERM /SATURDAY THROUGH SUNDAY NIGHT/...
AS OF 3 PM FRIDAY...PREFRONTAL SOUTHWESTERLY FLOW ON SATURDAY SHOULD
REMAIN AT 10 KT PREVENTING SEAS FROM ATTAINING HEIGHTS MORE THAN 2
FT. LATE SATURDAY NIGHT AS THE FRONT DRAWS NEAR THE COAST THERE MAY
BE A GENTLE BACKING OF THE FLOW FOLLOWED BY A MORE PRECIPITOUS VEER
ON SUNDAY ASSOCIATED WITH ACTUAL FROPA. THE FRONT WILL NOT MOVE VERY
FAR TO OUR SOUTH BEFORE STALLING WHICH PRECLUDES MUCH OF A SURGE OF
HIGH PRESSURE AND THUS ANY HIGHER WINDS. THUS THE VEER TO ENE FLOW
APPEARS TO BE THE MAIN EFFECT OF THE FROPA AS WIND SPEEDS AND WAVE
HEIGHTS REMAIN UNCHANGED...ALTHOUGH WAVE PERIODS MAY SHORTEN UP A
BIT.
LONG TERM /MONDAY THROUGH WEDNESDAY/...
AS OF 3 PM FRIDAY...DIMINISHING NORTHERLY SURGE AT THE START OF THE
PERIOD WILL LEAVE LIGHT AND VARIABLE WINDS OVER THE WATERS FOR MUCH
OF MON AND TUE GIVEN PROXIMITY TO THE STALLED FRONT. ANOTHER COLD
FRONT WILL DROP IN FROM THE NORTHWEST DURING THE SECOND HALF OF THE
PERIOD. THIS FRONT IS MORE DEFINED AND SHOULD BE ACCOMPANIED BY A
STRONGER NORTHERLY SURGE LATER WED INTO WED NIGHT. WINDS WILL
APPROACH A SOLID 15 KT WED NIGHT WITH GUSTS AROUND 20 KT POSSIBLE.
SEAS 2 TO 3 FT FOR MUCH OF THE PERIOD WILL BUILD AS HIGH AS 5 FT AS
THE PERIOD ENDS DUE TO THE PROLONGED AND STEADILY INCREASING NATURE
OF THE NORTHERLY SURGE.
&&
.ILM WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
NC...COASTAL FLOOD ADVISORY UNTIL 3 AM EDT EARLY THIS MORNING FOR
NCZ107.
MARINE...NONE.
&&
$$
SYNOPSIS...MBB
NEAR TERM...MJC/REK
SHORT TERM...MBB
LONG TERM...III
AVIATION...DCH/MRR
AREA FORECAST DISCUSSION
NWS GRAND FORKS ND
339 AM CDT SAT SEP 13 2014
.SHORT TERM...(TODAY THROUGH SUNDAY)
ISSUED AT 338 AM CDT SAT SEP 13 2014
NO CHANGE IN THE CURRENT FROST ADVISORY...ALTHOUGH A FEW LOCATIONS
OVER THE FAR EASTERN CWFA ARE IN THE MID 20S AT 08Z. WITH CIRRUS
INCREASING AND RETURN FLOW DEVELOPING DO NOT EXPECT TEMPERATURES
TO FALL MORE THAN 1 OR 2 DEGREES IN THE KVWU...KBJI...KBDO AND
KADC AREAS.
TODAY WILL BE A TRANSITION DAY. AS THE UNSEASONALLY COLD HIGH
MOVES SOUTH...LOW PRESSURE INTENSIFIES OVER SASKATCHEWAN SOUTH
WINDS WILL INCREASE BY MID DAY. THE MODELS INITIALIZED WELL AND
WILL FOLLOW THE HIGHER RESOLUTION HRRR AND NAM12 TODAY...BLENDING
THE NAM/GFS FOR TONIGHT INTO SUNDAY MORNING. TIMING OF WARM
ADVECTION PRECIPITATION AHEAD OF WELL DEFINED UPPER WAVE OVER
FAR NORTH-CENTRAL MONTANA SIMILAR TO PREVIOUS FORECAST REACHING THE
DEVILS LAKE BASIN AROUND 18Z AND SPREADING EAST. NAM/GFS HAVE
SMALL AREA OF 0C SHOWALTERS AND SOME ML CAPE BUT WILL NOT MENTION
TSRA ATTM. WITH WELL MIXED LAYER TO AROUND 800 MB...35 KTS AT 850
IN THE NAM AND NEAR 30 KTS IN THE GFS TRANSLATE TO GUSTS CLOSE TO
30 KTS POSSIBLE. MOS HAS 27 KTS AND WILL FOLLOW THAT FOR THE 18Z -
00Z PERIOD.
SECOND STRONGER SHORTWAVE...DROPPING ALONG THE ALBERTA/SASKATCHEWAN
BORDER IS FORECAST TO BE NEAR KDVL AT 06Z TONIGHT. SURFACE LOW
SLOWS AND WRAP AROUND SHRA SPREADING OVER THE EAST HALF OF THE
CWFA INTO SUNDAY MORNING.
THE COLUMN COOLS AND DRIES MOST AREAS SUNDAY...WITH LINGERING SHRA
OVER THE NORTHEAST PORTION OF THE CWFA...WITH STRONGER MID-UPPER
CAA ALONG SHEAR AXIS AND ENTRANCE REGION OF UPPER JET. THIS
QUICKLY MOVES OUT WITH PRECIPITATION ENDING BY 00Z MONDAY.
.LONG TERM...(SUNDAY NIGHT THROUGH FRIDAY)
ISSUED AT 338 AM CDT SAT SEP 13 2014
WINDS DIMINISH AND SKIES CLEAR AS HIGH PRESSURE MOVES ACROSS THE
CWFA. LOWS WILL FALL BACK INTO THE LOW TO MID 30S...BUT EXPECT
SUFFICIENT MIXING AT THIS TIME TO KEEP FROST/FREEZE RISK MINIMAL
FOR MONDAY MORNING. LIGHT SOUTHWEST WINDS AND PLENTIFUL SUNSHINE WILL
ALLOW MODEST WARM-UP MONDAY TO NEAR MID SEPTEMBER NORMALS. RISING
HEIGHTS AND CONTINUED WESTERLY FLOW WILL MAKE FOR A MAINLY CLEAR
AND MILD MONDAY NIGHT.
TUESDAY TO FRIDAY...CONFLUENT NW FLOW ALOFT FOR MUCH OF THE WEEK
WITH A QUICK TRANSITIONING PERIOD THURSDAY INTO FRIDAY. AS A RESULT
DRY CONDITIONS EXPECTED WITH MODERATING TEMPS AS THICKNESSES
INCREASE WITH RIDGING OVER THE FA BY THURSDAY. BY THURSDAY PM OR
FRIDAY DEPENDING ON MODEL OF CHOICE...500MB SW FLOW AND 850MB LLJ
BRING INSTABILITY INTO FA FROM WEST TO EAST. WENT WITH A MOSTLY
SHRA AND ISO THUNDER FOR WX GRIDS AS SHOWALTERS DO BECOME NEGATIVE
AHEAD OF THE SFC TROUGH EXPECTED TO IMPACT THE NORTHERN PLAINS
TOWARDS THE END OF THE WEEK. TEMPERATURES ABOVE NORMAL THROUGH THE
WEEK CAN BE EXPECTED WITH SOME HUMIDITY POSSIBLE BY WEEKS END.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT)
ISSUED AT 1151 PM CDT FRI SEP 12 2014
A MOSTLY CLEAR SKY WAS ACROSS THE FORECAST AREA. SOME CIRRUS WAS
SPILLING INTO THE NORTHWEST ZONES AND WILL SPREAD ACROSS THE AREA
OVERNIGHT. FOG LOOP INDICATED PATCHY CLOUDS AROUND 6 THOUSAND FT
OVER THE FAR EASTERN ZONES. ONLY BJI HAS COME IN WITH SOME
RESTRICTION TO VISIBILITY DUE TO FOG. WILL ADD SOME FOG TO BJI TAF.
EXPECT VFR CIGS LATE SAT AFTERNOON/EVENING FROM THE WEST AS NEXT
SYSTEM APPROACHES.
&&
.FGF WATCHES/WARNINGS/ADVISORIES...
ND...FROST ADVISORY UNTIL 8 AM CDT THIS MORNING FOR NDZ030-039-049-
052-053.
MN...FROST ADVISORY UNTIL 8 AM CDT THIS MORNING FOR MNZ001>003-005-
006-008-009-013>017-022>024-027>032-040.
&&
$$
SHORT TERM...EWENS
LONG TERM...JK
AVIATION...HOPPES
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
335 AM EDT SAT SEP 13 2014
.SYNOPSIS...
A SERIES OF SHORT WAVES WILL CARVE OUT PERSISTENT AND STRONG MID-
TROPOSPHERIC TROUGH OVER THE EASTERN UNITED STATES. THE FIRST
WAVE WILL PRODUCE SOME SHOWERS SATURDAY. SUBSEQUENT WAVES SHOULD
KEEP DEEP MOISTURE WELL TO OUR SOUTH...SO IT WILL BE RELATIVELY
DRY. SOME UNSEASONABLY COOL WEATHER IS LIKELY NEAR MID-WEEK BEFORE
THE PATTERN BEGINS TO WEAKEN BY THE END OF THE COMING WEEK.
&&
.NEAR TERM /UNTIL 9 AM THIS MORNING/...
CLOUDS WILL SLOWLY INCREASE WEST TO EAST OVERNIGHT THEN RAPIDLY IN
THE MORNING. A FAST MOVING SHORT-WAVE OVER MICHIGAN WILL BRING A
CHANCE OF SHOWERS INTO WESTERN AREAS BEFORE 6 AM. AND SLOWLY
SPREAD INTO THE WESTERN AREAS OF OUR COUNTY WARNING AREA.
THE HIGHER RESOLUTION MODELS AND SREF FAVOR THE CHANCE OF RAINFALL
MAINLY AFTER 7 AM.
&&
.SHORT TERM /9 AM THIS MORNING THROUGH 6 PM SUNDAY/...
THE FAST MOVING AND STRONG SHORT-WAVE SHOULD BRING RAIN AND
SHOWERS TO CENTRAL AND WESTERN AREAS IN THE MORNING AND INTO
MIDDAY BEFORE THE HIGHER PROBABILITIES SHIFT TO THE EAST. EASTERN
AREAS SHOULD SEE THE RAIN BY LATE MORNING AND INTO THE AFTERNOON
HOURS. THE SREF IMPLIES LITTLE OR NO RAIN AFTER ABOUT MIDDAY IN
CENTRAL AND WESTERN AREAS AND BY ABOUT 3 PM IN THE EAST. POPS
CRASH AFTER 18Z IN THE EAST.
THE RAIN WILL RAPIDLY END WEST TO EAST AND THERE COULD BE PEAKS OF
SUN IN THE WEST AND CENTRAL AREAS IN THE AFTERNOON. THIS FAST
MOVING SYSTEM AND ITS REINFORCING COLD AIR WILL BE TO OUR EAST BY
LATER AFTERNOON OR EARLY EVENING.
MOST AREAS WILL SEE A 2-4 HOUR PERIOD OF RAINFALL. RAINFALL
AMOUNTS SHOULD BE IN THE 0.10 TO 0.30 INCH RANGE IN MOST AREAS.
THE RAP FAVORS HIGHER AMOUNTS IN NORTH CENTRAL AND THE SREF IS A
SPLIT DECISION WITH SOME HIGHER AMOUNTS IN IN THE SOUTH AND
FARTHER NORTH.
&&
.LONG TERM /SUNDAY NIGHT THROUGH FRIDAY/...
BIG...1027MB HIGH PRESSURE SHOVES IN FROM THE WEST ON SATURDAY
NIGHT. THIS STARTS WHAT SHOULD BE AN ALMOST UNBROKEN STRING OF
COOL AND DRY WEATHER FOR THE ENTIRE LONG TERM PERIOD AND INTO
DAYS 8-PLUS. THE ONLY INKLING OF PRECIP WILL BE ON MON NIGHT AND
TUES MORNING. A WEAK FRONT MOVING DOWN FROM THE NW WILL TAP ONLY
MEAGER MOISTURES SINCE IT WILL LIE IN BETWEEN THE EARLY- WEEK HIGH
PRESSURE AND A SECOND EQUALLY DRY ANTICYCLONE MOVING IN FROM THE
UPPER GREAT LAKES AND MIDWEST. AT THE SAME TIME...THERE IS A WAVE
PROGGED TO BE SLIDING UP FROM THE GULF COAST STATES. HOWEVER...ALL
THE MODELS TAKE IT TO OUR SOUTH...GENERALLY THROUGH THE MID-
ATLANTIC STATES EARLY TUESDAY. THIS WOULD CREATE SOME RAIN/SHOWERS
ON MONDAY NIGHT AND EARLY TUESDAY. THERE MIGHT BE A BACKDOOR COLD
FRONT TRY TO MOVE DOWN AROUND THURSDAY...BUT NO MOISTURE IS TO BE
FOUND IN ITS VICINITY.
ONE POINT OF INTEREST WILL BE THE LOW TEMPERATURES SUNDAY MORNING
AND MONDAY MORNING. THE NORTHERN TIER...ESPECIALLY THE ICE BOX OF
KBFD...COULD GET INTO THE MID 30S BOTH MORNINGS - AND PERHAPS EVEN
THE LOWER 30S ON MONDAY MORNING. WHAT MIGHT BE MORE REMARKABLE IS
A POTENTIAL 30 TO 40F DIURNAL SWING ON MONDAY AS WINDS TURN TO THE
S/SW FOR THE DAYTIME BEFORE THE FRONT ARRIVES AT NIGHT/EARLY TUES.
BUT EVEN WITH THE GIANT SWING MONDAY SHOULD END UP JUST SLIGHTLY
BELOW NORMAL FOR MAXES. WELCOME AUTUMN.
&&
.AVIATION /08Z SATURDAY THROUGH WEDNESDAY/...
TIMING ON THE INCOMING RAIN IS THE BIG AVIATION CONCERN OVER THE
NEXT 12 HOURS. A SMALL BAND IS CURRENTLY MOVING ACROSS THE
SOUTHWESTERN TAF SITES...WHERE JST AND AOO HAVE MVFR CEILINGS. BFD
HAS GONE DOWN TO IFR AND SHOULD CONTINUE THROUGH THE MORNING.
THE SHOWERS WILL SPREAD ACROSS THE AREA BETWEEN ABOUT 09-15Z
SATURDAY MORNING ALONG WITH MVFR/IFR CONDITIONS DEVELOPING. THESE
CONDITIONS SHOULD CONTINUE UNTIL AROUND 18Z...BEFORE LIFTING AS
THE SYSTEM QUICKLY PASSES. WITH IMPROVING CONDITIONS SATURDAY
AFTERNOON.
OUTLOOK...
SUN...PATCHY AM FOG...OTHERWISE VFR.
MON...NO SIG WX.
MON NIGHT - TUE...A COLD FRONT WILL BRING REDUCED CONDITIONS WITH
SHOWERS.
WED...NO SIG WX.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...GRUMM
NEAR TERM...GRUMM
SHORT TERM...GRUMM/LA CORTE
LONG TERM...DANGELO
AVIATION...CERU/GARTNER
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
331 AM EDT SAT SEP 13 2014
.SYNOPSIS...
AN AREA OF LOW PRESSURE AT THE SURFACE AND DISTURBANCE ALOFT
WILL MOVE QUICKLY EAST ACROSS THE AREA SATURDAY. HIGH PRESSURE
AND FAIR WEATHER WILL RETURN ON SUNDAY. THE OVERALL PATTERN FAVORS
BELOW NORMAL TEMPERATURES FOR THE NEXT WEEK.
&&
.NEAR TERM /UNTIL 9 AM THIS MORNING/...
CLOUDS WILL SLOWLY INCREASE WEST TO EAST OVERNIGHT THEN RAPIDLY IN
THE MORNING. A FAST MOVING SHORT-WAVE OVER MICHIGAN WILL BRING A
CHANCE OF SHOWERS INTO WESTERN AREAS BEFORE 6 AM. AND SLOWLY
SPREAD INTO THE WESTERN AREAS OF OUR COUNTY WARNING AREA.
THE HIGHER RESOLUTION MODELS AND SREF FAVOR THE CHANCE OF RAINFALL
MAINLY AFTER 7 AM.
&&
.SHORT TERM /9 AM THIS MORNING THROUGH 6 PM SUNDAY/...
THE FAST MOVING AND STRONG SHORT-WAVE SHOULD BRING RAIN AND
SHOWERS TO CENTRAL AND WESTERN AREAS IN THE MORNING AND INTO
MIDDAY BEFORE THE HIGHER PROBABILITIES SHIFT TO THE EAST. EASTERN
AREAS SHOULD SEE THE RAIN BY LATE MORNING AND INTO THE AFTERNOON
HOURS. THE SREF IMPLIES LITTLE OR NO RAIN AFTER ABOUT MIDDAY IN
CENTRAL AND WESTERN AREAS AND BY ABOUT 3 PM IN THE EAST. POPS
CRASH AFTER 18Z IN THE EAST.
THE RAIN WILL RAPIDLY END WEST TO EAST AND THERE COULD BE PEAKS OF
SUN IN THE WEST AND CENTRAL AREAS IN THE AFTERNOON. THIS FAST
MOVING SYSTEM AND ITS REINFORCING COLD AIR WILL BE TO OUR EAST BY
LATER AFTERNOON OR EARLY EVENING.
MOST AREAS WILL SEE A 2-4 HOUR PERIOD OF RAINFALL. RAINFALL
AMOUNTS SHOULD BE IN THE 0.10 TO 0.30 INCH RANGE IN MOST AREAS.
THE RAP FAVORS HIGHER AMOUNTS IN NORTH CENTRAL AND THE SREF IS A
SPLIT DECISION WITH SOME HIGHER AMOUNTS IN IN THE SOUTH AND
FARTHER NORTH.
&&
.LONG TERM /SUNDAY NIGHT THROUGH FRIDAY/...
BIG...1027MB HIGH PRESSURE SHOVES IN FROM THE WEST ON SATURDAY
NIGHT. THIS STARTS WHAT SHOULD BE AN ALMOST UNBROKEN STRING OF
COOL AND DRY WEATHER FOR THE ENTIRE LONG TERM PERIOD AND INTO
DAYS 8-PLUS. THE ONLY INKLING OF PRECIP WILL BE ON MON NIGHT AND
TUES MORNING. A WEAK FRONT MOVING DOWN FROM THE NW WILL TAP ONLY
MEAGER MOISTURES SINCE IT WILL LIE IN BETWEEN THE EARLY- WEEK HIGH
PRESSURE AND A SECOND EQUALLY DRY ANTICYCLONE MOVING IN FROM THE
UPPER GREAT LAKES AND MIDWEST. AT THE SAME TIME...THERE IS A WAVE
PROGGED TO BE SLIDING UP FROM THE GULF COAST STATES. HOWEVER...ALL
THE MODELS TAKE IT TO OUR SOUTH...GENERALLY THROUGH THE MID-
ATLANTIC STATES EARLY TUESDAY. THIS WOULD CREATE SOME RAIN/SHOWERS
ON MONDAY NIGHT AND EARLY TUESDAY. THERE MIGHT BE A BACKDOOR COLD
FRONT TRY TO MOVE DOWN AROUND THURSDAY...BUT NO MOISTURE IS TO BE
FOUND IN ITS VICINITY.
ONE POINT OF INTEREST WILL BE THE LOW TEMPERATURES SUNDAY MORNING
AND MONDAY MORNING. THE NORTHERN TIER...ESPECIALLY THE ICE BOX OF
KBFD...COULD GET INTO THE MID 30S BOTH MORNINGS - AND PERHAPS EVEN
THE LOWER 30S ON MONDAY MORNING. WHAT MIGHT BE MORE REMARKABLE IS
A POTENTIAL 30 TO 40F DIURNAL SWING ON MONDAY AS WINDS TURN TO THE
S/SW FOR THE DAYTIME BEFORE THE FRONT ARRIVES AT NIGHT/EARLY TUES.
BUT EVEN WITH THE GIANT SWING MONDAY SHOULD END UP JUST SLIGHTLY
BELOW NORMAL FOR MAXES. WELCOME AUTUMN.
&&
.AVIATION /07Z SATURDAY THROUGH WEDNESDAY/...
TIMING ON THE INCOMING RAIN IS THE BIG AVIATION CONCERN OVER THE
NEXT 12 HOURS. A SMALL BAND IS CURRENTLY MOVING ACROSS THE
SOUTHWESTERN TAF SITES...WHERE JST AND AOO HAVE MVFR CEILINGS. BFD
HAS GONE DOWN TO IFR AND SHOULD CONTINUE THROUGH THE MORNING.
THE SHOWERS WILL SPREAD ACROSS THE AREA BETWEEN ABOUT 09-15Z
SATURDAY MORNING ALONG WITH MVFR/IFR CONDITIONS DEVELOPING. THESE
CONDITIONS SHOULD CONTINUE UNTIL AROUND 18Z...BEFORE LIFTING AS
THE SYSTEM QUICKLY PASSES. WITH IMPROVING CONDITIONS SATURDAY
AFTERNOON.
OUTLOOK...
SUN...PATCHY AM FOG...OTHERWISE VFR.
MON...NO SIG WX.
MON NIGHT - TUE...A COLD FRONT WILL BRING REDUCED CONDITIONS WITH
SHOWERS.
WED...NO SIG WX.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...LA CORTE/LAMBERT
NEAR TERM...GRUMM
SHORT TERM...GRUMM/LA CORTE
LONG TERM...DANGELO
AVIATION...CERU/GARTNER
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
146 AM EDT SAT SEP 13 2014
.SYNOPSIS...
AN AREA OF LOW PRESSURE AT THE SURFACE AND DISTURBANCE ALOFT
WILL MOVE QUICKLY EAST ACROSS THE AREA SATURDAY. HIGH PRESSURE
AND FAIR WEATHER WILL RETURN ON SUNDAY. THE OVERALL PATTERN FAVORS
BELOW NORMAL TEMPERATURES FOR THE NEXT WEEK.
&&
.NEAR TERM /UNTIL 9 AM THIS MORNING/...
CLOUDS WILL SLOWLY INCREASE WEST TO EAST OVERNIGHT THEN RAPIDLY IN
THE MORNING. A FAST MOVING SHORT-WAVE OVER MICHIGAN WILL BRING A
CHANCE OF SHOWERS INTO WESTERN AREAS BEFORE 6 AM. AND SLOWLY
SPREAD INTO THE WESTERN AREAS OF OUR COUNTY WARNING AREA.
THE HIGHER RESOLUTION MODELS AND SREF FAVOR THE CHANCE OF RAINFALL
MAINLY AFTER 7 AM.
&&
.SHORT TERM /9 AM THIS MORNING THROUGH 6 PM SUNDAY/...
THE FAST MOVING AND STRONG SHORT-WAVE SHOULD BRING RAIN AND
SHOWERS TO CENTRAL AND WESTERN AREAS IN THE MORNING AND INTO
MIDDAY BEFORE THE HIGHER PROBABILITIES SHIFT TO THE EAST. EASTERN
AREAS SHOULD SEE THE RAIN BY LATE MORNING AND INTO THE AFTERNOON
HOURS. THE SREF IMPLIES LITTLE OR NO RAIN AFTER ABOUT MIDDAY IN
CENTRAL AND WESTERN AREAS AND BY ABOUT 3 PM IN THE EAST. POPS
CRASH AFTER 18Z IN THE EAST.
THE RAIN WILL RAPIDLY END WEST TO EAST AND THERE COULD BE PEAKS OF
SUN IN THE WEST AND CENTRAL AREAS IN THE AFTERNOON. THIS FAST
MOVING SYSTEM AND ITS REINFORCING COLD AIR WILL BE TO OUR EAST BY
LATER AFTERNOON OR EARLY EVENING.
MOST AREAS WILL SEE A 2-4 HOUR PERIOD OF RAINFALL. RAINFALL
AMOUNTS SHOULD BE IN THE 0.10 TO 0.30 INCH RANGE IN MOST AREAS.
THE RAP FAVORS HIGHER AMOUNTS IN NORTH CENTRAL AND THE SREF IS A
SPLIT DECISION WITH SOME HIGHER AMOUNTS IN IN THE SOUTH AND
FARTHER NORTH.
&&
.LONG TERM /SUNDAY NIGHT THROUGH FRIDAY/...
BIG...1027MB HIGH PRESSURE SHOVES IN FROM THE WEST ON SATURDAY
NIGHT. THIS STARTS WHAT SHOULD BE AN ALMOST UNBROKEN STRING OF
COOL AND DRY WEATHER FOR THE ENTIRE LONG TERM PERIOD AND INTO
DAYS 8-PLUS. THE ONLY INKLING OF PRECIP WILL BE ON MON NIGHT AND
TUES MORNING. A WEAK FRONT MOVING DOWN FROM THE NW WILL TAP ONLY
MEAGER MOISTURES SINCE IT WILL LIE IN BETWEEN THE EARLY- WEEK HIGH
PRESSURE AND A SECOND EQUALLY DRY ANTICYCLONE MOVING IN FROM THE
UPPER GREAT LAKES AND MIDWEST. AT THE SAME TIME...THERE IS A WAVE
PROGGED TO BE SLIDING UP FROM THE GULF COAST STATES. HOWEVER...ALL
THE MODELS TAKE IT TO OUR SOUTH...GENERALLY THROUGH THE MID-
ATLANTIC STATES EARLY TUESDAY. THIS WOULD CREATE SOME RAIN/SHOWERS
ON MONDAY NIGHT AND EARLY TUESDAY. THERE MIGHT BE A BACKDOOR COLD
FRONT TRY TO MOVE DOWN AROUND THURSDAY...BUT NO MOISTURE IS TO BE
FOUND IN ITS VICINITY.
ONE POINT OF INTEREST WILL BE THE LOW TEMPERATURES SUNDAY MORNING
AND MONDAY MORNING. THE NORTHERN TIER...ESPECIALLY THE ICE BOX OF
KBFD...COULD GET INTO THE MID 30S BOTH MORNINGS - AND PERHAPS EVEN
THE LOWER 30S ON MONDAY MORNING. WHAT MIGHT BE MORE REMARKABLE IS
A POTENTIAL 30 TO 40F DIURNAL SWING ON MONDAY AS WINDS TURN TO THE
S/SW FOR THE DAYTIME BEFORE THE FRONT ARRIVES AT NIGHT/EARLY TUES.
BUT EVEN WITH THE GIANT SWING MONDAY SHOULD END UP JUST SLIGHTLY
BELOW NORMAL FOR MAXES. WELCOME AUTUMN.
&&
.AVIATION /06Z SATURDAY THROUGH WEDNESDAY/...
THE MVFR CEILINGS REMAIN OVER KBFD LATE THIS EVENING AND WILL
LIKELY REMAIN SO OVERNIGHT. ELSEWHERE SCATTERED LOW CLOUDS WILL
BE COVERED BY INCREASING MID AND HIGH CLOUDS THROUGH THE LATE
EVENING HOURS AHEAD OF ANOTHER DISTURBANCE RACING OUT OF THE UPPER
MIDWEST. EXPECT SHOWERS SPREADING ACROSS THE AREA BETWEEN ABOUT
09-15Z SATURDAY MORNING ALONG WITH MVFR/IFR CONDITIONS DEVELOPING.
THE SYSTEM BEING A FAST MOVER WILL MOVE THROUGH WITH IMPROVING
CONDITIONS SATURDAY AFTERNOON.
OUTLOOK...
SUN...PATCHY AM FOG...OTHERWISE VFR.
MON...NO SIG WX.
MON NIGHT - TUE...A COLD FRONT WILL BRING REDUCED CONDITIONS WITH
SHOWERS.
WED...NO SIG WX.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...LA CORTE/LAMBERT
NEAR TERM...GRUMM
SHORT TERM...GRUMM/LA CORTE
LONG TERM...DANGELO
AVIATION...LA CORTE/GARTNER
AREA FORECAST DISCUSSION
NWS NASHVILLE TN
1151 PM CDT FRI SEP 12 2014
.AVIATION 06Z DISCUSSION... PVA WILL BE IN PLACE THROUGH 12Z OVERNIGHT
AS A WEAK MID LEVEL IMPULSE WILL BE ON APPROACH. AS A
RESULT...LOW CIGS WILL PERSIST THROUGH AT LEAST 12Z.
THEREAFTER...THE LOW CLOUDINESS WILL STILL BE RATHER TOUGH TO
DISLODGE. THE MID AND UPPER FLOW STILL CARRIES A WEAK SOUTHERLY
COMPONENT. NEVERTHELESS...CIGS SHOULD BEGIN TO LIFT SOME TOWARD
18Z WITH PARTIAL CLEARING WEST BY 00Z.
OTW...ISOLATED SHOWERS HERE AND THERE WILL BE POSSIBLE UNTIL 12Z.
HOWEVER...THE EXPECTED COVERAGE DOES NOT WARRANT THE USAGE OF
VCNTY...TEMPO OR PROB GROUPS.
LOOK FOR CLOUDINESS TO BEGIN TO DECREASE FROM WEST TO EAST AFT
18Z.
&&
.PREV DISCUSSION... /ISSUED 725 PM CDT FRI SEP 12 2014/
UPDATE...
LATEST SURFACE OBS AND SATELLITE IMAGERY SHOWS LOW CLOUDS
CONTINUE TO BLANKET THE MID STATE...AND ACTUALLY EXTEND NORTHWARD
ALL THE WAY INTO CANADA SO THEY WONT BE GOING ANYWHERE ANYTIME
SOON. WATER VAPOR IMAGERY THIS EVENING DEPICTS A STRONG TROUGH
DIGGING SOUTHWARD INTO IOWA AND MISSOURI. AS THIS TROUGH SWINGS
THROUGH THE OHIO AND TENNESSEE VALLEYS OVERNIGHT...EXPECT A FEW
LIGHT SHOWERS AND SPRINKLES TO BREAK OUT ACROSS THE MID STATE
SIMILAR TO THE MOST RECENT HRRR MODEL RUNS. ALSO ANTICIPATE SOME
PATCHY FOG DEVELOPMENT IN THE HIGHER TERRAIN AREAS OF EASTERN
ZONES AS DEWPOINT DEPRESSIONS LOWER OVERNIGHT. DESPITE EXTENSIVE
CLOUD COVER...CAA WILL INCREASE OVERNIGHT WITH DRIER AIR
ADVECTING IN FROM THE NORTH AT THE SURFACE...WHICH SHOULD ALLOW
TEMPS TO FALL INTO THE UPPER 50S AND LOWER 60S FOR LOWS. CURRENT
FORECAST FOR TONIGHT ALREADY HAS CLOUDS...POPS...AND TEMPS WELL
HANDLED...AND ONLY MADE MINOR CHANGES FOR THE OVERNIGHT PERIOD.
SHAMBURGER
PREV DISCUSSION... /ISSUED 514 PM CDT FRI SEP 12 2014/
AVIATION 00Z DISCUSSION...
PVA WILL BE IN PLACE THROUGH 12Z OVERNIGHT AS A WEAK MID LEVEL IMPULSE
WILL BE ON APPROACH. AS A RESULT...LOW CIGS WILL PERSIST THROUGH
AT LEAST 12Z. THEREAFTER...THE LOW CLOUDINESS WILL STILL BE RATHER
TOUGH TO DISLODGE. THE MID AND UPPER FLOW STILL CARRIES A WEAK
SOUTHERLY COMPONENT. NEVERTHELESS...CIGS SHOULD BEGIN TO LIFT SOME
TOWARD 18Z WITH PARTIAL CLEARING WEST BY 00Z.
OTW...ISOLATED SHOWERS HERE AND THERE WILL BE POSSIBLE UNTIL 12Z.
HOWEVER...THE EXPECTED COVERAGE DOES NOT WARRANT THE USAGE OF
VCNTY...TEMPO OR PROB GROUPS.
PREV DISCUSSION... /ISSUED 256 PM CDT FRI SEP 12 2014/
DISCUSSION...IT WAS A CLOUDY DAY ACROSS MID TN WITH TEMPERATURES
MAINLY IN THE 70S...WHICH IS 5 TO 10 DEGREES COOLER THAN NORMAL. A
COLD FRONT HAD SETTLED WELL TO OUR SOUTHEAST. HIGH PRESSURE WAS
LOCATED WELL TO OUR NORTHWEST...CENTERED OVER THE NORTHERN PLAINS.
POST FRONTAL MOISTURE LINGERED OVER A WIDE AREA ...AND THIS
MOISTURE AND CLOUDINESS WILL REMAIN FOR A WHILE.
FOR TONIGHT...CLOUDY SKIES MAY EVENTUALLY PRODUCE A FEW LIGHT
SHOWERS OR PATCHY DRIZZLE AS A TROUGH AXIS PASSES ACROSS THE
REGION. THE CLOUDS WILL LOWER...AND SHOULD KEEP ANY FOG FORMATION
FROM BEING VERY DENSE. LOWS WILL BE A FEW DEGREES COOLER THAN
LAST NIGHT.
ON SATURDAY...MODELS SHOW A SMALL CHANCE FOR MORNING SHOWERS
PLATEAU...THEN DECREASING MOISTURE FROM NW TO SE. WE THINK CLOUDS
COULD BE STUBBORN...SO EXPECT OVERCAST SKIES ALL ZONES THROUGH
MIDDAY...THEN PARTIAL CLEARING GRADUALLY WORKING FROM NW TO SE
ACROSS THE MID STATE THROUGH THE AFTERNOON. HIGH TEMPS WILL AGAIN
BE QUITE PLEASANT...IN THE 70S. NORTH BREEZES WILL PICK UP A BIT
TO HELP THE CLEARING TREND. WINDS WILL REACH 10-20 MPH IN THE
EARLY AFTERNOON.
DRY WX WILL CONTINUE THROUGH THE REST OF THE WEEKEND. SATURDAY NIGHT
WILL BE A LITTLE CHILLY...WITH LOWS MAINLY LOWER 50S...BUT SOME
40S POSSIBLE AS WELL. SUNDAY WILL BE MAINLY SUNNY AND TEMPS WILL
RECOVER TO THE UPPER 70S.
LOOKING AHEAD...NEXT WEEK SHOULD BE QUIET IN THE WX DEPARTMENT.
A COUPLE OF WAVES AND FRONTS WILL SWING DOWN IN THE NORTHWEST
FLOW...BUT NO MAJOR RAINFALL OR TEMPERATURE ANOMALIES ARE EXPECTED.
RIGHT NOW...IT LOOKS LIKE THE STRONGEST SYSTEM WILL MOVE THROUGH
TUESDAY NIGHT...AND JUST INCLUDING 20 POPS AT THAT TIME. LOWS NEXT
WEEK WILL BE MOSTLY IN THE UPPER 50S TO AROUND 60...WITH HIGHS IN
THE MID 70S TO LOWER 80S.
13
PREV DISCUSSION... /ISSUED 1233 PM CDT FRI SEP 12 2014/
AVIATION...
MVFR-IFR CIGS ARE EXPECTED TO IMPROVE SLIGHTLY THROUGH THIS
AFTERNOON...BUT PERSISTENT VFR CIGS ARE NOT EXPECTED IN THE NEAR
TERM. WINDS WILL BE STEADY FROM THE NORTH TO NORTHWEST THROUGH THE
NIGHT SO VIS REDUCTIONS ARE NOT ANTICIPATED AT BNA OR CKV. FOR CSV
EXPECT IFR-LIFR VIS AND CIGS AGAIN DURING THE OVERNIGHT...WITH
CONDITIONS IMPROVING AT ALL THREE TAF SITES AFTER 14Z TOMORROW
UNDER A STEADY NORTH TO NORTHEASTERLY FLOW.
&&
.OHX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
21
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
235 AM CDT SAT SEP 13 2014
.SHORT TERM...(TODAY THROUGH TONIGHT)
ISSUED AT 235 AM CDT SAT SEP 13 2014
WATER VAPOR IMAGERY/RAP 500MB ANALYSIS SHOWING DEEP MID-LEVEL TROUGH
THAT GAVE THE AREA A CHILLY DAMP FRIDAY NOW OVER UPPER MI. RADAR
MOSAIC SHOWING LINGERING RAIN FROM CENTRAL UPPER MI INTO OVER FAR
EASTERN WI. IR SATELLITE SHOWED BULK OF LOW CLOUDS ASSOCIATED WITH
THIS TROUGH NOW NORTHEAST OF I-94. SURFACE HIGH PRESSURE/CLEARING
WAS WORKING INTO THE FORECAST AREA. ARX WEBCAM SHOWING EXTENSIVE
MISSISSIPPI RIVER VALLEY FOG WITH THE CLEARING/LIGHT WINDS. FOG WAS
HIT AND MISS ACROSS THE REST OF THE FORECAST AREA. OTHERWISE...
TEMPERATURES AS OF 2 AM WERE IN THE MIDDLE 30S TO MIDDLE 40S.
PLAN ON CONTINUING FROST ADVISORY THROUGH 8 AM THIS MORNING AS
TEMPERATURES FALL INTO THE LOWER/MIDDLE 30S. OTHERWISE...PLAN ON A
DRY/COOL SATURDAY AS A RIDGE OF HIGH PRESSURE PASSES OVERHEAD. LOOK
FOR HIGHS IN THE 55-65 DEGREE RANGE WHICH IS SOME 10-15 DEGREES
BELOW THE NORMAL...BUT MUCH BETTER THAN THE CHILLY CONDITIONS SEEN
ON FRIDAY.
LIGHT SOUTH WINDS/WARM AIR ADVECTION WILL THEN SET UP ACROSS THE
AREA TONIGHT AS THE HIGH MOVES INTO THE GREAT LAKES REGION AND A MID-
LEVEL/SURFACE TROUGH PUSHES FROM THE NORTHERN PLAINS INTO MN. SOME
MID/HIGH CLOUD WILL ALSO BE SEEN MAINLY NORTH OF I-94 IN THE WARM
AIR ADVECTION. LOOK FOR LOWS IN THE UPPER 30S TO THE LOWER 40S.
.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 235 AM CDT SAT SEP 13 2014
MID-LEVEL/SURFACE TROUGH PUSHES INTO THE AREA ON SUNDAY. MODELS
SHOWING WEAK 850MB MOISTURE TRANSPORT AND BEST SURFACE CONVERGENCE
NORTHEAST OF I-94 FOR A CHANCE OF SHOWERS IN THE AFTERNOON. THE REST
OF THE AREA LOOKS TO REMAIN DRY. OTHERWISE...PLAN ON ANOTHER EARLY
AUTUMN-LIKE DAY WITH HIGHS TOPPING OFF IN THE 60S.
SHOWER CHANCES WILL SPREAD ACROSS THE REST OF THE AREA SUNDAY NIGHT
AS THE TROUGH SLIPS SOUTHEAST. LOOK FOR LOWS IN THE 40S TO LOWER
50S. SHOWER CHANCES LOOK TO LINGER INTO MONDAY AS ANOTHER MID-LEVEL
TROUGH DROPS INTO THE AREA FROM THE NORTHERN PLAINS. THIS TROUGH
INTERACTS WITH THE BAROCLINIC ZONE ACROSS THE SOUTH WITH WEAK
FRONTOGENESIS IS NOTED IN THE 850-500MB LAYER PER THE NAM. THE GFS
IS A BIT STRONGER WITH THIS. WILL GO WITH A 20-50 POPS FOR NOW
MAINLY ALONG/SOUTH OF I-90. PLAN ON HIGHS MONDAY GENERALLY IN THE 60-
65 DEGREE RANGE.
FOR THE PERIOD TUESDAY THROUGH FRIDAY...
COOL/DRY NORTHWEST FLOW ALOFT WILL PREVAIL TUESDAY INTO WEDNESDAY
WITH HIGHS IN THE 60S AND LOWS IN THE UPPER 30S TO MIDDLE 40S.
SOME WARMING LOOKS TO TAKE PLACE THURSDAY INTO FRIDAY AS HIGH
PRESSURE MOVES OFF TO THE EAST AND A TROUGH MAKES ITS WAY OUT OF THE
INTERMOUNTAIN WEST INTO THE PLAINS. INCREASING WARM AIR
ADVECTION/MOISTURE TRANSPORT INTO THE REGION MAY PUSH A FEW SHOWERS
INTO THE AREA LATER THURSDAY NIGHT INTO FRIDAY. LOOK FOR HIGHS
THURSDAY IN THE 60S AND MID 60S TO THE LOWER 70S ON FRIDAY.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT)
ISSUED AT 1140 PM CDT FRI SEP 12 2014
WITH CLOUDS HOLDING T/TD SPREADS CLOSE THROUGH THE DAY...AND
CLEARING SKIES JUST IN TIME FOR NIGHTTIME...ITS A FAVORABLE SETUP
FOR DIURNAL COOLING INDUCED RIVER VALLEY FOG. NOT AS MUCH T/TD
SPREAD TO MAKEUP - ONLY 3 DEGREES AT 04Z. SFC WINDS WILL BE LIGHT
THROUGH THE NIGHT. HOWEVER...A SIGNIFICANT DRAWBACK WILL BE THE
DEPTH OF THE LIGHT WIND LAYER. RAP BUFKIT SOUNDINGS CONTINUE TO
BRING 10+ KTS OF WIND BY 300 FT FOR MOST OF THE NIGHT. THE NAM HAS A
SLIGHTLY DEEPER LIGHT WIND FOR THE FIRST PART OF THE
OVERNIGHT...DECREASING BEFORE 12Z. GENERALLY - THE SHALLOWER THE
LIGHT WIND LAYER...THE LESS FAVORABLE FOR DENSE FOG. CLOUDS AREN/T
COMPLETELY CLEAR EITHER...WITH SCATTERED PATCHES MOVING OVERHEAD.
CERTAINLY...SOME VSBY RESTRICTIONS ARE LIKELY...AND COULD SEE
THICKER FOG/STRATUS BANK SITTING ON THE MISSISSIPPI RIVER...BUT
UNSURE IF IT WILL SPREAD ACROSS KLSE. THIS COULD BE A SCENARIO WHERE
VSBYS DO DROP TO 1/4SM BRIEFLY...THEN BACK UP TO P6SM...THEN
2SM...AS FOG SLOSHES AROUND. CONFIDENCE LOW IN HOW THIS WILL
PLAYOUT...SO WILL LIKELY HOLD WITH MVFR VSBYS AND BCFG FOR NOW.
SOMETHING TO WATCH CLOSELY TONIGHT.
HIGH PRESSURE BUILDS IN SATURDAY...AND WILL RESULT IN VFR CONDITIONS
OUTSIDE OF THE EARLY MORNING FOG POTENTIAL. WINDS WILL GRADUALLY
SWING FROM WEST TO SOUTHWEST. LATER SAT NIGHT...SOME CIGS NEAR 4KFT
COULD RETURN AS LOW LEVEL WARM AIR ADVECTION AND WEAK MOISTURE
TRANSPORT LEAD A SHORTWAVE MOVING EAST ACROSS THE NORTHERN PLAINS.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...FROST ADVISORY FROM 3 AM TO 8 AM CDT SATURDAY FOR WIZ017-029-033-
034-042>044.
MN...FROST ADVISORY FROM 3 AM TO 8 AM CDT SATURDAY FOR MNZ086-087-094-
095.
IA...FROST ADVISORY FROM 3 AM TO 8 AM CDT SATURDAY FOR IAZ008>010-018-
019-029.
&&
$$
SHORT TERM...DAS
LONG TERM...DAS
AVIATION...RIECK
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
1140 PM CDT FRI SEP 12 2014
.SHORT TERM...(THIS EVENING THROUGH SATURDAY)
ISSUED AT 257 PM CDT FRI SEP 12 2014
MAIN FORECAST CONCERNS ARE FROST AND FOG POTENTIAL TONIGHT.
LATEST WATER VAPOR SATELLITE IMAGERY SHOWING VIGOROUS SHORTWAVE
TROUGH OVER THE NORTHERN PLAINS. MOSAIC RADAR INDICATING
FRONTOGENETICAL BAND OF RAIN EXTENDING FROM NORTHEAST WISCONSIN INTO
NORTHEAST IOWA PER 12.15Z RAP 700-600MB FN VECTOR CONVERGENCE.
ALSO...MOSAIC RADAR SHOWING DIURNALLY DRIVEN SCATTERED SHOWERS OVER
CENTRAL MINNESOTA UNDERNEATH MAIN SHORTWAVE TROUGH.
TONIGHT...SHORTWAVE TROUGH AND ASSOCIATED LOW LEVEL MOISTURE/RAIN
PROGGED TO PUSH QUICKLY EAST INTO MICHIGAN THIS EVENING PER THE
LATEST 12.12Z GFS/NAM AND 12.15Z RAP RELATIVE HUMIDITY FIELDS. THIS
IS EVIDENT PER LATEST VISIBLE SATELLITE IMAGERY SHOWING DIURNAL
CUMULUS FIELD WEST OF A LINE FROM FAIRMONT MINNESOTA TO NEAR DULUTH
MINNESOTA. THIS CUMULUS FIELD WILL QUICKLY EVAPORATE DUE TO LOSS OF
DAYTIME HEATING THIS EVENING AND ALLOW SKIES TO CLEAR WEST TO EAST
ACROSS THE FORECAST AREA. SURFACE RIDGE BUILDS INTO THE FORECAST
AREA BY 06Z AND PRODUCE CALM WINDS AND DRIER AIRMASS TO ADVECT IN.
TEMPERATURES WILL BE ABLE TO FALL RAPIDLY INTO THE 30S AND THE UPPER
20S IN THE COLD SPOTS OF CENTRAL WISCONSIN. FOR THIS...A FROST
ADVISORY WILL BE IN EFFECT FOR PORTIONS OF SOUTHEAST
MINNESOTA...NORTHEAST IOWA AND CENTRAL WISCONSIN TONIGHT. IN
ADDITION...THE COMBINATION OF RAIN TODAY...CALM WINDS AND INVERSION
DEVELOPING TONIGHT PER BUFKIT SOUNDINGS...AREAS OF FOG WILL DEVELOP
IN RIVER VALLEYS AND PARTS OF CENTRAL WISCONSIN AFTER 06Z.
DRY WEATHER CONDITIONS AND UNSEASONABLY COOL TEMPERATURES WILL
PREVAIL ACROSS THE AREA SATURDAY...AS SURFACE RIDGE REMAINS IN
CONTROL.
.LONG TERM...(SATURDAY NIGHT THROUGH FRIDAY)
ISSUED AT 257 PM CDT FRI SEP 12 2014
WARMER AIR ADVECTS INTO THE FORECAST AREA SUNDAY OUT AHEAD OF NEXT
SHORTWAVE TROUGH TO AFFECT THE REGION. TEMPERATURES WILL BE A FEW
DEGREES WARMER AND SLIGHTLY BELOW NORMAL.
NEXT CONCERN IS SHORTWAVE TROUGH MOVING OVER THE GREAT LAKES REGION
EMBEDDED IN THE WEST TO NORTHWEST FLOW SUNDAY NIGHT INTO MONDAY.
BOTH THE 12.12Z GFS/NAM SHOW STRONG PV ADVECTION/QG FORCING AND
FN CONVERGENCE FOCUSED OVER THE SOUTHERN HALF OF THE FORECAST
AREA. SOME SLIGHT DIFFERENCES OCCUR WITH THE PLACEMENT AND TIMING
OF SURFACE FEATURES BETWEEN THE 12.12Z GFS/NAM/ECMWF. WITH THE
MODELS CONTINUE TO SHOW DECENT DYNAMIC FORCING/LIFT IN ASSOCIATED
WITH SHORTWAVE TROUGH...WILL MAINTAIN PRECIPITATION CHANCES SUNDAY
INTO MONDAY MAINLY FOR THE SOUTHERN HALF OF THE FORECAST AREA.
MAIN FORECAST CONCERN ARE PRECIPITATION CHANCES FRIDAY...OTHERWISE
TEMPERATURES TUESDAY THROUGH FRIDAY. THE 12.12Z GFS/GEM/ECMWF
CONTINUE TO HAVE GOOD RUN TO RUN CONSISTENCY IN DIGGING UPPER LEVEL
TROUGH OVER THE NORTHEAST UNITED STATES AND GREAT LAKES REGION AND
SURFACE RIDGE DOMINATING THE UPPER MIDWEST TUESDAY THROUGH THURSDAY.
WITH SUBSIDENCE OVER THE FORECAST AREA...DUE TO SURFACE RIDGE...DRY
WEATHER CONDITIONS CAN BE EXPECTED ACROSS THE FORECAST AREA DURING
THIS TIME FRAME. TEMPERATURES SHOULD BE NEAR OR SLIGHTLY BELOW
NORMAL TUESDAY THROUGH THURSDAY...AS THE 12.00Z GFS/GEM/ECMWF
INDICATE 850MB TEMPERATURES RANGING FROM PLUS 5 TO PLUS 10 DEGREES
CELSIUS AND 12.12Z GEFS SHOW STANDARD ANOMALIES OF MINUS 0.5 TO
MINUS 1 DEGREE CELSIUS. SIGNIFICANT DIFFERENCES SHOW UP BETWEEN THE
12.12Z GFS/ECMWF FRIDAY...AS THE 12.12Z GFS MORE AMPLIFIED WITH
UPPER LEVEL RIDGE OVER THE UPPER MIDWEST THAN THE ECMWF AND THE
12.12Z ECMWF IS SLOWER IN PROGRESSING THE UPPER LEVEL RIDGE INTO THE
UPPER MIDWEST AND GREAT LAKES REGION. THIS HAS IMPACTS ON HOW FAST
WARMER AIR ADVECTS INTO THE REGION AND TIMING OF SURFACE WARM FRONT
INTO THE FORECAST AREA. THIS SURFACE WARM FRONT WILL BE THE FOCUS
OF PRECIPITATION CHANCES FRIDAY...WITH BOTH THE 12.12Z GFS/ECMWF
INDICATE DECENT 850MB MOISTURE TRANSPORT AND CONVERGENCE IN
ASSOCIATION WITH IMPULSE OVER THE NORTHERN PLAINS AND NORTHERN
ROCKIES. CONFIDENCE IN FORECAST ON FRIDAY IS LOW DUE TO TIMING AND
STRENGTH OF UPPER LEVEL RIDGE.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT)
ISSUED AT 1140 PM CDT FRI SEP 12 2014
WITH CLOUDS HOLDING T/TD SPREADS CLOSE THROUGH THE DAY...AND
CLEARING SKIES JUST IN TIME FOR NIGHTTIME...ITS A FAVORABLE SETUP
FOR DIURNAL COOLING INDUCED RIVER VALLEY FOG. NOT AS MUCH T/TD
SPREAD TO MAKEUP - ONLY 3 DEGREES AT 04Z. SFC WINDS WILL BE LIGHT
THROUGH THE NIGHT. HOWEVER...A SIGNIFICANT DRAWBACK WILL BE THE
DEPTH OF THE LIGHT WIND LAYER. RAP BUFKIT SOUNDINGS CONTINUE TO
BRING 10+ KTS OF WIND BY 300 FT FOR MOST OF THE NIGHT. THE NAM HAS A
SLIGHTLY DEEPER LIGHT WIND FOR THE FIRST PART OF THE
OVERNIGHT...DECREASING BEFORE 12Z. GENERALLY - THE SHALLOWER THE
LIGHT WIND LAYER...THE LESS FAVORABLE FOR DENSE FOG. CLOUDS AREN/T
COMPLETELY CLEAR EITHER...WITH SCATTERED PATCHES MOVING OVERHEAD.
CERTAINLY...SOME VSBY RESTRICTIONS ARE LIKELY...AND COULD SEE
THICKER FOG/STRATUS BANK SITTING ON THE MISSISSIPPI RIVER...BUT
UNSURE IF IT WILL SPREAD ACROSS KLSE. THIS COULD BE A SCENARIO WHERE
VSBYS DO DROP TO 1/4SM BRIEFLY...THEN BACK UP TO P6SM...THEN
2SM...AS FOG SLOSHES AROUND. CONFIDENCE LOW IN HOW THIS WILL
PLAYOUT...SO WILL LIKELY HOLD WITH MVFR VSBYS AND BCFG FOR NOW.
SOMETHING TO WATCH CLOSELY TONIGHT.
HIGH PRESSURE BUILDS IN SATURDAY...AND WILL RESULT IN VFR CONDITIONS
OUTSIDE OF THE EARLY MORNING FOG POTENTIAL. WINDS WILL GRADUALLY
SWING FROM WEST TO SOUTHWEST. LATER SAT NIGHT...SOME CIGS NEAR 4KFT
COULD RETURN AS LOW LEVEL WARM AIR ADVECTION AND WEAK MOISTURE
TRANSPORT LEAD A SHORTWAVE MOVING EAST ACROSS THE NORTHERN PLAINS.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...FROST ADVISORY FROM 3 AM TO 8 AM CDT SATURDAY FOR WIZ017-029-033-
034-042>044.
MN...FROST ADVISORY FROM 3 AM TO 8 AM CDT SATURDAY FOR MNZ086-087-094-
095.
IA...FROST ADVISORY FROM 3 AM TO 8 AM CDT SATURDAY FOR IAZ008>010-018-
019-029.
&&
$$
SHORT TERM...DTJ
LONG TERM...DTJ
AVIATION...RIECK
AREA FORECAST DISCUSSION
NWS MIAMI FL
1105 AM EDT SAT SEP 13 2014
.UPDATE...
WHILE SHOWER AND THUNDERSTORM ACTIVITY HAS SUBSIDED ACROSS THE
REGION THIS MORNING...THE POTENTIAL FOR ACTIVE CONVECTION
CONTINUES. RECENT VISIBLE SATELLITE IMAGERY INDICATES ACTIVE
CONVECTION IN THE EASTERN GULF ASSOCIATED WITH THE AREA OF LOW
PRESSURE OFF THE SOUTHWEST FLORIDA COAST AND ADDITIONAL CONVECTION
IN THE CENTRAL BAHAMAS ISLANDS. THE 12Z SOUNDING INDICATED A PWAT
AROUND 1.9 INCHES AND INDICATED A SIGNIFICANT COOLING TREND IN THE
MID LEVELS AS WELL. GIVEN THE GENERAL CLEARING TREND OVER THE
PENINSULA THIS MORNING...DAY TIME HEATING IS EXPECTED TO DRIVE
CONVECTION THIS AFTERNOON AND EARLY EVENING WITH THE GREATEST
COVERAGE OF SHOWERS AND THUNDERSTORMS STILL EXPECTED IN THE
WESTERN INTERIOR AND WESTERN PORTIONS OF THE PENINSULA...INCLUDING
THE NAPLES METRO AREAS.
60
&&
.PREV DISCUSSION... /ISSUED 830 AM EDT SAT SEP 13 2014/
AVIATION...
RATHER DISORGANIZED UPPER LOW, WITH A FEW DISTURBANCES TRAILING
TO THE EAST, WILL BE THE IMPETUS FOR STORMS TODAY. LARGE MASS OF
MID LEVEL DRY AIR PER WATER VAPOR LOOP, MAY STAY NORTH OF THE
REGION TODAY, UNLIKE YESTERDAY. PERHAPS SOME OF THIS DRY AIR WILL
WRAP INTO THE CIRCULATION OF THE UPPER LOW, BUT THAT MAY NOT MEAN
MUCH SINCE THE LOW IS ALREADY OFF THE SW FL COAST. LAMP GUIDANCE
INDICATES THAT A SEA BREEZE WILL DEVELOP ALONG THE EAST COAST,
PERHAPS KEEPING MOST CONVECTION INLAND AND WEST COAST. THIS IS UP
AGAINST THE HRRR WHICH IS AGGRESSIVE PAINTING STORMS ALONG THE
BEACHES AND MOST TERMINALS BY MID AFTERNOON. THE TAFS CAN BE FINE
TUNED ONCE RAOB DATA ARRIVES, BUT WILL INSERT VCTS FOR NOW, AS
PREVIOUS DISCUSSION MENTIONED VCTS FOR ALL TAFS, BUT TAFS ONLY
CONTAINED VCSH. PERHAPS SOME OF THE SHOWERS OFFSHORE OF PBI ARRIVE
LATER THIS MORNING. PERSISTENCE OF CLOUD COVER ALONG THE EAST
COAST WILL ALSO GO A LONG WAY IN DETERMINING STORM EVOLUTION
TODAY. CONFIDENCE IS BELOW AVERAGE.
PREV DISCUSSION... /ISSUED 431 AM EDT SAT SEP 13 2014/
SHORT TERM...(TODAY-MONDAY)
RECENTLY ANIMATED WATER VAPOR LOOP SHOWED AN UPPER LOW CENTERED OVER
SOUTH FLORIDA SLOWLY TRACKING WESTWARD AND A RIDGE AXIS ORIENTED
FROM EAST TO WEST ACROSS THE NORTHERN GULF COAST STATES. PLENTY OF
DEEP LAYER MOISTURE EAST OF THIS UPPER LOW COMBINED WITH UPPER-LEVEL
DIVERGENCE WILL CONTINUE TO SUPPORT WIDESPREAD RAINFALL TODAY
.ESPECIALLY ALONG THE SOUTHEAST COAST AND ACROSS THE ATLANTIC
WATERS THROUGH THE MORNING HOURS. THE LATEST HRRR MODEL RUN APPEARS
TO HAVE INITIALIZED WELL WITH THE CURRENT RADAR TRENDS AND GENERALLY
INDICATES THIS MORNING ACTIVITY CONTINUING ACROSS THE EASTERN
AREAS INCLUDING PALM BEACH, BROWARD AND MIAMI-DADE BEFORE SHIFTING
INLAND AND TOWARD THE GULF COAST THROUGH THE MID TO LATE
AFTERNOON/EARLY EVENING PERIOD. THIS SOLUTION MAKES SENSE WITH THE
UPPER LOW SHIFTING WESTWARD AND LIGHT TO MODERATE SOUTHEAST LOW-
LEVEL FLOW CONTINUING. THIS PATTERN WILL KEEP THE POTENTIAL FOR
LOCALIZED FLOODING UP THROUGH THIS EVENING...ESPECIALLY OVER THE
AREAS THAT ARE ALREADY SATURATED FROM EARLIER RAINFALL (AREAS HAVE
RECEIVED 2-4 INCHES WITH HIGHER AMOUNTS UP TO 7" JUST INLAND OF
BOCA RATON OVER THE PAST 24-36 HRS). MODEL SOUNDINGS SUPPORT THE
ACTIVITY TAPERING OFF OVER THE FAR SOUTHEASTERN AREAS OR TOWARD
MIAMI THROUGH THE MORNING AND AFTERNOON HOURS WITH MAINLY
SATURATED PROFILES ABOVE A SLIGHTLY DRIER LAYER FROM THE SURFACE
TO 700MB. AS A RESULT...MAXIMUM TEMPERATURES HAVE BEEN SLIGHTLY
UNDERCUT BY A FEW DEGREES COMPARED TO GUIDANCE...MAINLY DUE TO
PLENTY OF CLOUD COVERAGE ANTICIPATED. IF THIS COVERAGE BEGINS TO
BREAK THROUGH THE DAY...TEMPERATURES WILL NEED TO BE ADJUSTED
ACCORDINGLY. THE MOIST TREND WITH SOUTHEAST FLOW WILL PERSIST
THROUGH SUNDAY BEFORE SOME DRIER AIR MOVES IN FROM THE WEST AND
THE RIDGE BUILDS BACK ACROSS THE REGION INTO THE UPCOMING WEEK.
/85
LONG TERM (TUESDAY-FRIDAY)...
THE LATEST EXTENDED GUIDANCE REMAINS IN DECENT AGREEMENT ON THE
LARGE SCALE AND GENERALLY INDICATES FALLING UPPER HEIGHTS IN
RESPONSE TO A DEEPENING UPPER TROUGH ACROSS THE REGION. A FRONTAL
BOUNDARY IS PROJECTED TO SHIFT SOUTHWARD AND STALL NORTH OF THE AREA
THROUGH THE SECOND HALF OF THE WEEK. THE ECMWF SEEMS TO BE THE MORE
BULLISH SOLUTION AND SHOWS THE MOISTURE AXIS ASSOCIATED WITH THIS
BOUNDARY PROGRESSING FARTHER SOUTH THAN THE GFS/GFS ENSEMBLE MEAN
WITH SSW LOW-LEVEL FLOW SETTING UP OVER THE AREA BY THURSDAY. THE
COMBINATION OF THE FRONT AND FALLING UPPER HEIGHTS ALONG WITH SSW
LOW-LEVEL FLOW WOULD FAVOR MUCH OF THE RAINFALL SETTING UP OVER THE
EAST COAST/METRO AREAS BY THURSDAY.
/85
AVIATION...
A LARGE AREA OF SHOWERS AND THUNDERSTORMS OVER THE ATLANTIC WATERS
WERE DEVELOPING ON THE NORTHEAST SIDE OF THE MID/UPPER LEVEL
VORTICITY MOVING WEST ACROSS THE FLORIDA STRAITS. THESE
SHOWERS/STORMS WERE MOVING QUICKLY TO THE NORTHWEST TOWARDS THE
BROWARD AND MIAMI-DADE TAF SITES...AND THEY MAY MOVE OVER THE TAF
SITES THROUGH THE EARLY MORNING HOURS. BRIEF MVFR/IFR CONDITIONS AND
GUSTY WINDS UP TO 30 KNOTS ARE POSSIBLE. THE AREA OF LOW PRESSURE
OVER THE SOUTHEAST GULF AND THE UPPER LEVEL LOW WILL CONTINUE TO
MOVE WEST TODAY AND HAVE LESS OF AN INFLUENCE OVER THE REGION
THROUGHOUT THE DAY. THIS COMBINED WITH THE OVERNIGHT CONVECTION MAY
LIMIT SHOWER/STORM DEVELOPMENT FOR THE EAST COAST METRO AREAS DURING
THE DAY. HOWEVER...DEEP MOISTURE IN THE SOUTHEAST LOW LEVEL FLOW
WILL CONTINUE...SO KEPT VCTS IN FOR THE TAF SITES. AT KAPF...SHOWER
AND STORM DEVELOPMENT IS FORECAST TO BECOME MORE LIKELY AS THE DAY
PROGRESSES...AS THE INFLUENCE OF THE UPPER LOW INCREASES. LIGHT
WINDS WILL CONTINUE THROUGH THE OVERNIGHT HOURS OUTSIDE OF SHOWERS
AND STORMS...AND THEN BECOME SOUTHEAST AROUND 10 KNOTS DURING THE
DAY.
/84
MARINE...
AN UPPER LOW WILL KEEP THE RAIN CHANCES IN THE FORECAST ACROSS THE
MARINE AREAS THROUGH THE REMAINDER OF THE WEEKEND WITH LIGHT TO
MODERATE SOUTHEAST WINDS CONTINUING. WINDS AND SEAS WILL BE LOCALLY
HIGHER IN AND AROUND HEAVIER SHOWERS AND STORMS. HIGH PRESSURE WILL
BUILD BACK ACROSS THE REGION THROUGH THE FIRST HALF OF THE UPCOMING
WEEK WITH SOUTHEAST WINDS CONTINUING.
&&
.PRELIMINARY POINT TEMPS/POPS...
WEST PALM BEACH 87 76 87 76 / 40 30 50 30
FORT LAUDERDALE 87 77 87 79 / 40 40 60 20
MIAMI 85 77 87 78 / 40 40 60 20
NAPLES 87 75 89 76 / 70 30 60 20
&&
.MFL WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
AM...NONE.
GM...NONE.
&&
$$
SHORT TERM...21/KM
LONG TERM....60/BD
AREA FORECAST DISCUSSION
NWS TALLAHASSEE FL
1030 AM EDT Sat Sep 13 2014
.Near Term [Rest of Today]...
The previous forecast remains largely on track, so only minor
tweaks were made. The leading edge of an expansive stratus deck,
roughly marking the location of a quasi-stationary front, extended
from near Mobile to near Atlanta this morning. When combined with
14Z objective MSAS analysis of MSLP and observed winds, this
places the front very close to the northwest corner of our
forecast area. The environment along and immediately southeast of
the front is characterized by mid-70s surface dewpoints and PWATs
around 2" (per GOES sounder). Meanwhile, some drier air was
encroaching on the southeast part of the forecast area based on
the latest water vapor loops and objective RAP analysis.
Tallahassee appeared to be on the cusp of the drier air, with a
PWAT of 1.9" on the 12Z sounding. Therefore, the higher rain
chances that were already included in the northwest half of the
forecast area seem on track at this time. Convection-allowing
models (CAM) almost unanimously show fairly widespread
thunderstorm activity just ahead of the front in our SE Alabama
and western Florida Panhandle zones after about 19-20Z. They also
agree that the storms are likely to linger until a few hours after
sunset again, particularly in the Florida Panhandle. PoPs were
bumped up in the Florida Panhandle for the evening hours. With
less convective coverage in the Florida Big Bend and south-central
Georgia, those areas could see highs in the mid-90s again. To the
north and west, highs should be from around 90 to the lower 90s.
The 12Z Tallahassee sounding did indicate stronger E-NE flow than
yesterday, likely due to the influence of the passing tropical
wave to the south of the area. However, radar VWPs and RAP
analysis place the axis of the deep mid-upper level ridge near
the northwest corner of our forecast area with a notable weakness
in the flow. This will likely lead to slow storm motions in the
region with the highest PoPs. Slow storm motions, storm-scale
interactions, and the moist environment will provide adequate
ingredients for localized heavy rainfall. The heavy rain wording
was maintained in the forecast. Some CAMs indicate rainfall rates
as high as 4-5" in just under 2 hours, so isolated flash flooding
will be possible. However, the threat is expected to be isolated
enough to preclude the issuance of a Flash Flood Watch.
&&
.Prev Discussion [642 AM EDT]...
.Short Term [Tonight Through Monday]...
Although weak upper level ridging will continue to dominate the
northern Gulf Coast and SE U.S during the remainder of the weekend
and into early next week (before it is eventually replaced by a trof
towards mid week), plenty of deep layer tropical moisture will
continue to flow into the region from the Gulf of Mexico and western
Atlantic. This will keep PoPs above climo through the short term
period with daytime rain chances generally in the 40-50% range, with
decent PoPs continuing well into the evening hours, especially
tonight over NW portions of the CWA. Temps are expected to remain
above normal as well, with highs mainly in the lower to a few mid
90s away from the coast, with overnight lows in the lower to middle
70s.
.Long Term [Monday Night Through Friday]...
The main uncertainty for the extended forecast is to what extent
the weak system moving westward into the Gulf will impact our
area. The collaborated NHC/WPC forecast takes the system westward
to a position south of Houston by mid-week and keeps it weak. Deep
moisture will continue to increase across the area with a stalled
frontal boundary also in the vicinity. These ingredients point to
an unsettled period coming up with an above average chance of rain
by mid-week. Some locally heavy rain is possible given the weak
boundary and deep tropical moisture expected to be in place. This
could be further enhanced by the Gulf system depending on its
evolution, but that evolution is much more uncertain. Daytime
highs are expected to be held down in the mid 80s from Tuesday
through most of the week given the expected cloud cover and
increased rain coverage.
.Aviation...
[through 12z Sunday] Other than brief patchy fog early, generally
VFR conditions are expected. Scattered to numerous SHRA/TSRA will
develop this afternoon & evening across southeast AL, the FL
Panhandle, & southwest GA, affecting KDHN, KABY, & KECP with
occasional gusty winds, low cigs, and poor vis. Elsewhere VFR
conditions will continue. SHRA/TSRA should slowly diminish around
midnight or shortly after.
.Marine...
Winds and seas will be slightly elevated this weekend as a weak
tropical disturbance passes well to the south of the coastal waters.
Thereafter, a very weak surface pressure pattern will return to the
marine area, with typically low summertime winds and seas expected
once again.
.Fire Weather...
Red Flag conditions are not expected through at least this weekend.
.Hydrology...
As mentioned above, some locally heavy rainfall (with up to 2" to 4"
amounts) will be possible today in some of the slow moving storms to
the north and west of Tallahassee, but any heavy amounts should be
isolated in nature and not have much of a hydrological impact
through early next week. By the middle of the week, however, an
upper level trof will replace the current ridge which will be
retreating westward, and before the cooler and drier air is allowed
to seep into the region by late in the week or next weekend, more
widespread heavy rainfall could fall over the CWA. Should this
occur, some more significant rises along area rivers and streams
could take place, so this situation will be worth monitoring.
&&
.Preliminary Point Temps/PoPs...
Tallahassee 96 73 93 72 92 / 20 30 40 20 50
Panama City 90 76 89 76 89 / 40 60 40 20 50
Dothan 91 72 92 72 92 / 70 60 50 30 50
Albany 92 72 92 73 92 / 50 50 50 30 50
Valdosta 95 71 94 71 93 / 20 30 40 30 50
Cross City 93 72 92 71 92 / 30 40 40 20 50
Apalachicola 90 77 89 76 88 / 20 20 40 20 40
&&
.TAE Watches/Warnings/Advisories...
FL...None.
GA...None.
AL...None.
GM...None.
&&
$$
NEAR TERM...LAMERS
SHORT TERM...GOULD
LONG TERM...DVD
AVIATION...FOURNIER
MARINE...GOULD
FIRE WEATHER...FOURNIER
HYDROLOGY...GOULD
AREA FORECAST DISCUSSION
NWS MELBOURNE FL
1019 AM EDT SAT SEP 13 2014
.DISCUSSION...
.UPDATE...
MORNING SOUNDINGS FROM TAMPA AND THE CAPE INDICATE PRECIPITABLE
WATER VALUES RANGING FROM 1.83 TO 1.96 INCHES AND WITH SOUTHERLY LOW
LVL FLOW BACKING TO THE E/ENE ABOVE 700 MBS. AT THE SFC...SOUTHERLY
FLOW THIS MORNING IS FORECAST TO BECOME SE THIS AFTERNOON WITH FLOW
AROUND THE ATLC RIDGE. THE LOW LVL FLOW IS ALSO FORECAST TO BECOME
SE BY THIS AFTERNOON WHICH WILL ALLOWS THE EAST COAST SEA BREEZE TO
DEVELOP AND PUSH INTO THE INTERIOR DURING THE MID TO LATE AFTN HOURS
TODAY. IN THE UPPER LEVELS...AN UPPER LEVEL LOW OFF THE SW FL COAST
IS FORECAST TO MOVE SW WITH ANOTHER UPPER LVL LOW WELL NE FROM THE
NRN BAHAMAS FORECAST TO ALSO GENERALLY MOVE SW THIS AFTN AND
EVENING. THESE FEATURES MAY PROVIDE SOME ADDITIONAL LIFT ACROSS OUR
FAR SRN ZONES WHERE THE DEEPEST MOISTURE WILL RESIDE TODAY. CURRENT
FORECAST LOOKS ON TRACK WITH ONLY SOME SMALL TWEAKS TO POPS/TEMPS.
LOWEST RAIN CHANCES EXPECTED ALONG THE VOLUSIA COUNTY COAST AND
HIGHEST RAIN CHANCES AROUND 40 PCT FROM THE SRN INTERIOR INTO LAKE
COUNTY.
&&
.AVIATION...CURRENT TERMINALS HAVE VCTS IN FOR PORTIONS OF THE
AFTERNOON ALONG SRN TERMINALS BY MID DAY AND INTERIOR TERMINALS THIS
AFTERNOON. RECENT HRRR MODEL RUNS SUGGEST SCT SHRA/TSRA SHOULD DVLP
OVER THE INTERIOR BY MID AFTN AND PUSH WESTWARD TWD LAKE COUNTY AND
KLEE VCTY BY LATE AFTERNOON. WILL MONITOR TRENDS AND MAY ADD SHORT
TEMPO GROUP FOR TSRA AT KLEE LATER THIS AFTN. OTHERWISE EXPECT
MAINLY VFR CONDS OUTSIDE OF SCATTERED CONVECTION MOVING WESTWARD
ACROSS THE INTERIOR IN THE MID-LATE AFTERNOON.
&&
.MARINE...S WINDS AT 6-10 KNOTS AT BUOY 41009 THE LAST SEVERAL HOURS
WITH SEAS AROUND 2.6 FT. WINDS WILL BECOME SE AROUND 10 KNOTS WITH
SEAS MAINLY AROUND 2 FT...POSSIBLY UP TO 2-3 FT OFFSHORE ACROSS THE
NRN OFFSHORE WATERS.
&&
.MLB WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
AM...NONE.
&&
$$
VOLKMER/SEDLOCK
AREA FORECAST DISCUSSION
NWS MELBOURNE FL
1015 AM EDT SAT SEP 13 2014
.DISCUSSION...
.UPDATE...
MORNING SOUNDINGS FROM TAMPA AND THE CAPE INDICATE PRECIPITABLE
WATER VALUES RANGING FROM 1.83 TO 1.96 INCHES AND WITH SOUTHERLY LOW
LVL FLOW BACKING TO THE E/ENE ABOVE 700 MBS. AT THE SFC...SOUTHERLY
FLOW THIS MORNING IS FORECAST TO BECOME SE THIS AFTERNOON WITH FLOW
AROUND THE ATLC RIDGE. THE LOW LVL FLOW IS ALSO FORECAST TO BECOME
SE BY THIS AFTERNOON WHICH WILL ALLOWS THE EAST COAST SEA BREEZE TO
DEVELOP AND PUSH INTO THE INTERIOR DURING THE MID TO LATE AFTN HOURS
TODAY. IN THE UPPER LEVELS...AN UPPER LEVEL LOW OFF THE SW FL COAST
IS FORECAST TO MOVE SW WITH ANOTHER UPPER LVL LOW WELL NE FROM THE
NRN BAHAMAS FORECAST TO ALSO GENERALLY MOVE SW THIS AFTN AND
EVENING. THIS FEATURES MAY PROVIDE SOME ADDITIONAL LIFT ACROSS OUR
FAR SRN ZONES WHERE THE DEEPEST MOISTURE WILL RESIDE TODAY. CURRENT
FORECAST LOOKS ON TRACK WITH ONLY SOME SMALL TWEAKS TO POPS/TEMPS.
LOWEST RAIN CHANCES EXPECTED ALONG THE VOLUSIA COUNTY COAST AND
HIGHEST RAIN CHANCES AROUND 40 PCT FROM THE SRN INTERIOR INTO LAKE
COUNTY.
&&
.AVIATION...CURRENT TERMINALS HAVE VCTS IN FOR PORTIONS OF THE
AFTERNOON ALONG SRN TERMINALS BY MID DAY AND INTERIOR TERMINALS THIS
AFTERNOON. RECENT HRRR MODEL RUNS SUGGEST SCT SHRA/TSRA SHOULD DVLP
OVER THE INTERIOR BY MID AFTN AND PUSH WESTWARD TWD LAKE COUNTY AND
KLEE VCTY BY LATE AFTERNOON. WILL MONITOR TRENDS AND MAY ADD SHORT
TEMPO GROUP FOR TSRA AT KLEE LATER THIS AFTN. OTHERWISE EXPECT
MAINLY VFR CONDS OUTSIDE OF SCATTERED CONVECTION MOVING WESTWARD
ACROSS THE INTERIOR IN THE MID-LATE AFTERNOON.
&&
.MARINE...S WINDS AT 6-10 KNOTS AT BUOY 41009 THE LAST SEVERAL HOURS
WITH SEAS AROUND 2.6 FT. WINDS WILL BECOME SE AROUND 10 KNOTS WITH
SEAS MAINLY AROUND 2 FT...POSSIBLY UP TO 2-3 FT OFFSHORE ACROSS THE
NRN OFFSHORE WATERS.
&&
.MLB WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
AM...NONE.
&&
$$
VOLKMER/SEDLOCK
AREA FORECAST DISCUSSION
NWS MIAMI FL
830 AM EDT SAT SEP 13 2014
.AVIATION...
RATHER DISORGANIZED UPPER LOW, WITH A FEW DISTURBANCES TRAILING
TO THE EAST, WILL BE THE IMPETUS FOR STORMS TODAY. LARGE MASS OF
MID LEVEL DRY AIR PER WATER VAPOR LOOP, MAY STAY NORTH OF THE
REGION TODAY, UNLIKE YESTERDAY. PERHAPS SOME OF THIS DRY AIR WILL
WRAP INTO THE CIRCULATION OF THE UPPER LOW, BUT THAT MAY NOT MEAN
MUCH SINCE THE LOW IS ALREADY OFF THE SW FL COAST. LAMP GUIDANCE
INDICATES THAT A SEA BREEZE WILL DEVELOP ALONG THE EAST COAST,
PERHAPS KEEPING MOST CONVECTION INLAND AND WEST COAST. THIS IS UP
AGAINST THE HRRR WHICH IS AGGRESSIVE PAINTING STORMS ALONG THE
BEACHES AND MOST TERMINALS BY MID AFTERNOON. THE TAFS CAN BE FINE
TUNED ONCE RAOB DATA ARRIVES, BUT WILL INSERT VCTS FOR NOW, AS
PREVIOUS DISCUSSION MENTIONED VCTS FOR ALL TAFS, BUT TAFS ONLY
CONTAINED VCSH. PERHAPS SOME OF THE SHOWERS OFFSHORE OF PBI ARRIVE
LATER THIS MORNING. PERSISTENCE OF CLOUD COVER ALONG THE EAST
COAST WILL ALSO GO A LONG WAY IN DETERMINING STORM EVOLUTION
TODAY. CONFIDENCE IS BELOW AVERAGE.
&&
.PREV DISCUSSION... /ISSUED 431 AM EDT SAT SEP 13 2014/
SHORT TERM...(TODAY-MONDAY)
RECENTLY ANIMATED WATER VAPOR LOOP SHOWED AN UPPER LOW CENTERED OVER
SOUTH FLORIDA SLOWLY TRACKING WESTWARD AND A RIDGE AXIS ORIENTED
FROM EAST TO WEST ACROSS THE NORTHERN GULF COAST STATES. PLENTY OF
DEEP LAYER MOISTURE EAST OF THIS UPPER LOW COMBINED WITH UPPER-LEVEL
DIVERGENCE WILL CONTINUE TO SUPPORT WIDESPREAD RAINFALL TODAY
..ESPECIALLY ALONG THE SOUTHEAST COAST AND ACROSS THE ATLANTIC
WATERS THROUGH THE MORNING HOURS. THE LATEST HRRR MODEL RUN APPEARS
TO HAVE INITIALIZED WELL WITH THE CURRENT RADAR TRENDS AND GENERALLY
INDICATES THIS MORNING ACTIVITY CONTINUING ACROSS THE EASTERN
AREAS INCLUDING PALM BEACH, BROWARD AND MIAMI-DADE BEFORE SHIFTING
INLAND AND TOWARD THE GULF COAST THROUGH THE MID TO LATE
AFTERNOON/EARLY EVENING PERIOD. THIS SOLUTION MAKES SENSE WITH THE
UPPER LOW SHIFTING WESTWARD AND LIGHT TO MODERATE SOUTHEAST LOW-
LEVEL FLOW CONTINUING. THIS PATTERN WILL KEEP THE POTENTIAL FOR
LOCALIZED FLOODING UP THROUGH THIS EVENING...ESPECIALLY OVER THE
AREAS THAT ARE ALREADY SATURATED FROM EARLIER RAINFALL (AREAS HAVE
RECEIVED 2-4 INCHES WITH HIGHER AMOUNTS UP TO 7" JUST INLAND OF
BOCA RATON OVER THE PAST 24-36 HRS). MODEL SOUNDINGS SUPPORT THE
ACTIVITY TAPERING OFF OVER THE FAR SOUTHEASTERN AREAS OR TOWARD
MIAMI THROUGH THE MORNING AND AFTERNOON HOURS WITH MAINLY
SATURATED PROFILES ABOVE A SLIGHTLY DRIER LAYER FROM THE SURFACE
TO 700MB. AS A RESULT...MAXIMUM TEMPERATURES HAVE BEEN SLIGHTLY
UNDERCUT BY A FEW DEGREES COMPARED TO GUIDANCE...MAINLY DUE TO
PLENTY OF CLOUD COVERAGE ANTICIPATED. IF THIS COVERAGE BEGINS TO
BREAK THROUGH THE DAY...TEMPERATURES WILL NEED TO BE ADJUSTED
ACCORDINGLY. THE MOIST TREND WITH SOUTHEAST FLOW WILL PERSIST
THROUGH SUNDAY BEFORE SOME DRIER AIR MOVES IN FROM THE WEST AND
THE RIDGE BUILDS BACK ACROSS THE REGION INTO THE UPCOMING WEEK.
/85
LONG TERM (TUESDAY-FRIDAY)...
THE LATEST EXTENDED GUIDANCE REMAINS IN DECENT AGREEMENT ON THE
LARGE SCALE AND GENERALLY INDICATES FALLING UPPER HEIGHTS IN
RESPONSE TO A DEEPENING UPPER TROUGH ACROSS THE REGION. A FRONTAL
BOUNDARY IS PROJECTED TO SHIFT SOUTHWARD AND STALL NORTH OF THE AREA
THROUGH THE SECOND HALF OF THE WEEK. THE ECMWF SEEMS TO BE THE MORE
BULLISH SOLUTION AND SHOWS THE MOISTURE AXIS ASSOCIATED WITH THIS
BOUNDARY PROGRESSING FARTHER SOUTH THAN THE GFS/GFS ENSEMBLE MEAN
WITH SSW LOW-LEVEL FLOW SETTING UP OVER THE AREA BY THURSDAY. THE
COMBINATION OF THE FRONT AND FALLING UPPER HEIGHTS ALONG WITH SSW
LOW-LEVEL FLOW WOULD FAVOR MUCH OF THE RAINFALL SETTING UP OVER THE
EAST COAST/METRO AREAS BY THURSDAY.
/85
AVIATION...
A LARGE AREA OF SHOWERS AND THUNDERSTORMS OVER THE ATLANTIC WATERS
WERE DEVELOPING ON THE NORTHEAST SIDE OF THE MID/UPPER LEVEL
VORTICITY MOVING WEST ACROSS THE FLORIDA STRAITS. THESE
SHOWERS/STORMS WERE MOVING QUICKLY TO THE NORTHWEST TOWARDS THE
BROWARD AND MIAMI-DADE TAF SITES...AND THEY MAY MOVE OVER THE TAF
SITES THROUGH THE EARLY MORNING HOURS. BRIEF MVFR/IFR CONDITIONS AND
GUSTY WINDS UP TO 30 KNOTS ARE POSSIBLE. THE AREA OF LOW PRESSURE
OVER THE SOUTHEAST GULF AND THE UPPER LEVEL LOW WILL CONTINUE TO
MOVE WEST TODAY AND HAVE LESS OF AN INFLUENCE OVER THE REGION
THROUGHOUT THE DAY. THIS COMBINED WITH THE OVERNIGHT CONVECTION MAY
LIMIT SHOWER/STORM DEVELOPMENT FOR THE EAST COAST METRO AREAS DURING
THE DAY. HOWEVER...DEEP MOISTURE IN THE SOUTHEAST LOW LEVEL FLOW
WILL CONTINUE...SO KEPT VCTS IN FOR THE TAF SITES. AT KAPF...SHOWER
AND STORM DEVELOPMENT IS FORECAST TO BECOME MORE LIKELY AS THE DAY
PROGRESSES...AS THE INFLUENCE OF THE UPPER LOW INCREASES. LIGHT
WINDS WILL CONTINUE THROUGH THE OVERNIGHT HOURS OUTSIDE OF SHOWERS
AND STORMS...AND THEN BECOME SOUTHEAST AROUND 10 KNOTS DURING THE
DAY.
/84
MARINE...
AN UPPER LOW WILL KEEP THE RAIN CHANCES IN THE FORECAST ACROSS THE
MARINE AREAS THROUGH THE REMAINDER OF THE WEEKEND WITH LIGHT TO
MODERATE SOUTHEAST WINDS CONTINUING. WINDS AND SEAS WILL BE LOCALLY
HIGHER IN AND AROUND HEAVIER SHOWERS AND STORMS. HIGH PRESSURE WILL
BUILD BACK ACROSS THE REGION THROUGH THE FIRST HALF OF THE UPCOMING
WEEK WITH SOUTHEAST WINDS CONTINUING.
&&
.PRELIMINARY POINT TEMPS/POPS...
WEST PALM BEACH 87 76 87 76 / 40 30 50 30
FORT LAUDERDALE 84 77 87 79 / 50 40 60 20
MIAMI 85 77 87 78 / 50 40 60 20
NAPLES 87 75 89 76 / 70 30 60 20
&&
.MFL WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
AM...NONE.
GM...NONE.
&&
$$
SHORT TERM...85/AG
LONG TERM....85/AG
AVIATION...84/AK
AREA FORECAST DISCUSSION...UPDATED
NWS JACKSON MS
1039 AM CDT SAT SEP 13 2014
.UPDATE...DECREASED HOURLY TEMPERATURES AND OVERALL HIGHS FOR TODAY
WITH EXPECTED CLOUD COVER AND LOW-LEVEL COLD AIR ADVECTION TO
PERSIST. HAVE ALSO REMOVED THUNDER WORDING FOR SE AREAS WHERE FRONT
HAS PASSED THROUGH ALREADY.
.DISCUSSION...LOW STRATUS CLOUDS AND POCKETS OF LIGHT DRIZZLE
BLANKET THE ENTIRE REGION AS LOW-LVL COLD AIR ADVECTION OCCURS IN
LOWEST 150MB WITH NORTH SURFACE WINDS AT 10-15 MPH. THIS IS LEADING
TO SOME OF THE COOLEST READINGS OF THE LATE SUMMER SEASON WITH
TEMPERATURES STILL IN THE LOW 60S NORTH TO UPPER 60S CENTRAL AND LOW
70S SOUTH. WITH LOW STRATUS TRAPPED UNDERNEATH INVERSION PER
OBSERVED AND BUFR SOUNDINGS, FEEL CLOUD COVER WILL PERSIST AT GOOD
WHILE INTO THE EARLY TO MID AFTERNOON AND THUS KEEP TEMPERATURES AND
INSTABILITY LOW. EVENTUAL MIXING SHOULD HELP SLOW EROSION OF CLOUDS
IN SE BUT IT MAY BE TOO LITTLE TO LATE FOR INSTABILITY TO BUILD FOR
ANY THUNDERSTORM POTENTIAL. SSEO AND LATEST RUC ANALYSIS DEPICT
BETTER TSTORM ENVIRONMENT WILL BE DISPLACED FARTHER SOUTH AND EAST
OF PINE BELT. CLOUDS WILL SLOWLY ERODE FROM THE NORTH AS WELL BUT
I-20 CORRIDOR MAY BE IN CENTRAL POINT WHERE IT PERSISTS THE LONGEST.
HAVE FOLLOWED CLOSE TO GFS LAMP TRENDS THROUGH THE DAY AS IT SEEMS
TO BE CAPTURING THE CAA WELL. AN UPDATED AVIATION DISCUSSION CAN BE
FOUND BELOW. /ALLEN/
&&
.AVIATION...MORNING IFR CIGS WL GRADUALLY RISE TO MVFR CIGS THIS
AFTN AS AN ABUNDANCE OF COLD ADVECTION STRATUS WILL IMPACT TAF SITES
TODAY AND PERHAPS INTO TONIGHT. LINGERING RAIN CHANCES WILL BE
MOSTLY CONFINED IN THE HBG/PIB TO MEI AREA...BUT BY THIS EVENING
EXPECT MOST OF THE AREA TO BE RAIN-FREE. LOW LEVEL MIXING SHOULD BE
STRONG ENOUGH LATE TONIGHT AND EARLY SUNDAY MORNING TO LIMIT ANY FOG
POTENTIAL. /EC/22/
&&
.PREV DISCUSSION... /ISSUED 426 AM CDT SAT SEP 13 2014/
DISCUSSION...
TODAY THROUGH SUNDAY NIGHT...
STRONG SURFACE HIGH PRESSURE (1031 MB) CENTERED OVER THE PLAINS AND
MIDWEST IS RESPONSIBLE FOR TODAY`S SHALLOW COOL AIR INTRUSION
BENEATH THE THE SUBTROPICAL RIDGE (591 DM). THE COLD ADVECTION IS
LEADING TO A CONSIDERABLE AMOUNT OF STRATUS AND EXPECT THIS TO
CONTINUE FOR MOST OF THE DAY RESULTING IN RATHER COOL AFTERNOON
TEMPERATURES THAT WILL STRUGGLE TO REACH THE LOWER 70S IN THE UPPER
DELTA REGION. THE EXCEPTION TO THIS WILL BE IN THE HATTIESBURG AREA
WHERE WEAKER COLD ADVECTION AND LESS LOW CLOUD COVER SHOULD ALLOW
TEMPERATURE TO REACH THE LOW TO MID 80S. AS WE GO FROM TONIGHT INTO
SUNDAY...THE AIRMASS WILL BEGIN TO MODIFY AND ALLOW FOR SLIGHTLY
WARMER TEMPERATURES. MODELS AGREE THAT DEEPER MOISTURE WILL BEGIN TO
RETURN...ESPECIALLY BY SUNDAY AFTERNOON AND EVENING ALONG THE I-59
CORRIDOR FROM HBG TO MEI. /EC/
MONDAY THROUGH NEXT SATURDAY...
PRETTY GOOD AGREEMENT REMAINS BETWEEN THE GFS AND ECMWF THIS MORNING
IN REGARDS TO THE WEATHER ACROSS THE FORECAST AREA THROUGH MUCH OF
THE LONG TERM PERIOD. DECENT RAIN CHANCES LOOK TO REMAIN IN THE
FORECAST MONDAY THROUGH WEDNESDAY IN THE VICINITY OF A SLOW TO WASH
OUT BOUNDARY MEANDERING ABOUT AND AFFECTING MAINLY THE SOUTHERN HALF
OF THE ARKLAMISS. MOST OF THIS ACTIVITY LOOKS TO MAINLY BE CONFINED
TO THE AFTERNOON AND EARLY EVENING HOURS...BUT SOME COULD LINGER INTO
THE OVERNIGHT HOURS. BIGGEST CONCERN DURING THIS TIME WILL BE THE
POTENTIAL FOR HEAVY RAINFALL...AGAIN PRIMARILY IN THE SOUTH...AS
PRECIPITABLE H2O VALUES REMAIN AROUND THE 2.00 INCH RANGE.
RAIN CHANCES LOOK TO DECREASE THURSDAY THROUGH SATURDAY AS A DECENT
SURGE OF DRIER AIR FILTERS SOUTH AND DEEPER INTO THE CWA AS HIGH
PRESSURE BUILDS INTO THE REGION FROM THE NORTH. IF THIS INDEED
UNFOLDS...IT SHOULD BRING A NOTICEABLY DRIER FEEL TO THE AIR...ALONG
WITH SOME SLIGHTLY COOLER DAYTIME AND OVERNIGHT TEMPERATURES THROUGH
AT LEAST SATURDAY. UNTIL THEN...LOOK FOR A CONTINUATION OF HUMID
CONDITIONS MONDAY THROUGH WEDNESDAY AS HIGHS CLIMB TO NEAR 90 AND
LOWS GENERALLY RANGE FROM THE MID 60S TO AROUND 70. OBVIOUSLY
MONDAY THROUGH WEDNESDAY...AFTERNOON CONVECTION AND ASSOCIATED CLOUD
COVER WILL PLAY A LARGE ROLL IN HOW WARM MOST LOCATIONS GET...
ESPECIALLY ALONG AND SOUTH OF THE INTERSTATE 20 CORRIDOR. /19/
&&
.PRELIMINARY POINT TEMPS/POPS...
JACKSON 77 64 85 68 / 21 11 14 12
MERIDIAN 80 64 87 67 / 25 14 21 16
VICKSBURG 76 61 84 66 / 21 13 11 9
HATTIESBURG 86 68 91 71 / 37 14 27 21
NATCHEZ 76 63 85 68 / 29 14 18 13
GREENVILLE 72 58 82 63 / 20 11 9 9
GREENWOOD 73 58 83 62 / 20 10 10 10
&&
.JAN WATCHES/WARNINGS/ADVISORIES...
MS...NONE.
LA...NONE.
AR...NONE.
&&
$$
ALLEN/22/EC/19
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
609 AM EDT SAT SEP 13 2014
.SYNOPSIS...
A FLOOD WATCH HAS BEEN ISSUED FOR SATURDAY AS A STALLED COLD
FRONT CONTINUES UNSETTLED WEATHER ACROSS THE AREA. THIS FRONT WILL
REMAIN IN THE VICINITY ON SUNDAY...BEFORE LIFTING BACK NORTH ON
MONDAY...BUT UNSETTLED WEATHER WILL PERSIST. A STRONGER COLD FRONT WILL
CROSS THE AREA ON TUESDAY...BRINGING COOLER AND DRIER WEATHER FOR
THE LATTER HALF OF NEXT WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 600 AM SATURDAY...A FLOOD WATCH HAS BEEN POSTED FOR THE
ENTIRE ILM CWA...AND IS IN EFFECT FROM 6 AM THIS MORNING THROUGH 6
AM SUNDAY MORNING.
A STALLED FRONTAL BOUNDARY LYING EAST-WEST NEARLY ALONG THE NC-SC
BORDER WILL LIKELY MEANDER BOTH NORTH AND SOUTH THROUGHOUT THE
NEAR TERM PERIOD. INITIALLY...IT MAY TEMPORARILY PUSH NORTHWARD
DUE TO A VIGOROUS UPPER S/W TROF PUSHING FROM THE GREAT LAKES TO
THE NE STATES TODAY. THEN SETTLING BACK TO THE SOUTH
TONIGHT...WITH MODELS HINTING THAT IT MAY DROP SOUTH OF THE ILM
CWA DURING SUNDAY. PLENTY OF MOISTURE ON EITHER SIDE OF THE
FRONTAL BOUNDARY WITH PWS 2+ INCHES. TO AID PCPN DEVELOPMENT...
FORCING IE. UVVS...WILL BE PROVIDED BY THE SFC FRONT ITSELF...AND
UPPER DYNAMICS IN THE FORM OF A S/W TROF OR VORT...WHICH WILL
FURTHER PROVIDE ADDITIONAL LIFT. NORTH OF THE FRONT WILL OBSERVE
OVERRUNNING TYPE PCPN...IE. STRATIFORM RAINS. HOWEVER...ELEVATED
CONVECTION REMAINS A GOOD POSSIBILITY DUE TO ELEVATED
INSTABILITY...IE. ELEVATED CAPE. SOUTH OF THE FRONT...THE
CHARACTER OF THE PCPN WILL BE MORE CONVECTIVE. WITH THE FA
LOCATED DIRECTLY ON EITHER SIDE OF THIS FRONT...THE CWA WILL THEN
BE SUBJECTED TO PCPN THAT WILL MOVE ACROSS ALREADY SATURATED
GROUNDS...OVER AND OVER AGAIN IE. TRAINING...WITH THE END RESULT
LIKELY FLOODING. THUS...A 24 HR FLOOD WATCH HAS BEEN ISSUED FOR
THE ENTIRE ILM CWA...IN EFFECT FROM 6AM SAT THRU 6AM SUN.
VARIOUS MODEL MOS GUIDANCE INDICATE WIDESPREAD 80S FOR MAX TEMPS
TODAY. DEPENDING ON WHICH SIDE OF THE FRONT ONE IS...THE RANGE
WILL RUN FROM THE LOW 80S NORTHERN PORTIONS OF THE ILM CWA TO MID-
UPPER 80S SOUTHERN PORTIONS OR SOUTH OF THE FRONT. THE WIDESPREAD
CLOUDS AND PCPN MAY FURTHER PREVENT TEMPS FROM CLIMBING...ESPECIALLY
NORTH OF THE FRONT WHERE UPPER 70S IS NOT OUT OF THE QUESTION. THE
COOLER AND DRIER AIR BEHIND THE FRONT REMAINS WELL UPSTREAM...FROM
VIRGINIA AND NORTHWARD. THUS...EVEN IF TEMPORARY FROPA DOES
OCCUR...THE COOLER AND DRIER AIRMASS WILL REMAIN WELL UPSTREAM AND
UNABLE TO INFILTRATE THE REGION DURING THIS PERIOD.
&&
.SHORT TERM /SUNDAY THROUGH MONDAY NIGHT/...
AS OF 300 AM SATURDAY...AN EXPANDING TROUGH AND A PERSISTENT RIDGE
WILL ENGAGE IN BATTLE OVERHEAD THROUGH EARLY NEXT WEEK FOR POSITION
OVER THE CAROLINAS. ALMOST LIKE THE OLD CHILDHOOD GAME OF "RED
ROVER"...EACH FEATURE WILL TRY TO BREAK THROUGH THE OTHER...BUT THE
RIDGE WILL CALL THE TROUGH OVER ONE TOO MANY TIMES...EARNING THE
TROUGH A VICTORY...DISPLACING THE RIDGE BY MONDAY NIGHT. THIS
FORCES THE COLD FRONT BELOW TO BECOME NEARLY STATIONARY SUNDAY AND
MONDAY...WAVERING BACK AND FORTH ACROSS THE AREA...CONTINUING THE
UNSETTLED WEATHER PATTERN.
SURFACE FRONT WILL BE ALONG THE SOUTHERN TIER...OR JUST SOUTH...OF
THE CWA DURING SUNDAY BEFORE SLOWLY LIFTING NORTH AGAIN ON MONDAY.
WHILE INSTABILITY WILL BE LIMITED DUE TO WIDESPREAD CLOUD
COVER...AND UPPER SUPPORT WILL REMAIN MINIMAL...PERSISTENT MOIST
FLOW ATOP THE FRONT COMBINED WITH SURFACE CONVERGENCE ALONG IT (AND
RESIDUAL BOUNDARIES) IN A VERY MOIST COLUMN WILL PRODUCE PERIODS OF
RAIN/TSTMS SUNDAY AND MONDAY. BEST PRECIP CHANCES MAY BE IN THE
SOUTHERN AND WESTERN ZONES SUNDAY AND THIS IS WHERE THE HIGHEST QPF
IS EXPECTED...BUT ALL AREAS WILL LIKELY SEE SHOWERS AND STORMS. A
BRIEF RESPITE IN CONVECTIVE COVERAGE WILL OCCUR WITH LOSS OF HEATING
SUNDAY NIGHT...BEFORE MORE SCATTERED CONVECTION DEVELOPS MONDAY AS
THE FRONT LIFTS TO THE NORTH PRODUCING A BRIEF PERIOD OF WAA AND
SUMMER-LIKE CONVECTION. THIS WILL BE SHORT LIVED HOWEVER...AS THIS
FRONT WILL RETURN BACK TO THE SOUTHEAST AS A COLD FRONT BENEATH A
STRONG VORTICITY IMPULSE MOVING TO THE NORTH EITHER VERY LATE MONDAY
NIGHT...OR JUST BEYOND THIS PERIOD. ANOTHER ROUND OF HEAVIER PRECIP
MAY ACCOMPANY THIS FRONT LATE MONDAY HOWEVER...AND CANNOT AT ANY
TIME FORECAST POP BELOW CHC THROUGH THE PERIOD...WITH HIGHEST
OCCURRING SUNDAY AND THEN AGAIN LATE MONDAY.
HIGHS SUNDAY WILL BE SEVERAL DEGREES BELOW NORMAL THANKS TO
CLOUDS...RAIN...AND COOL NORTHERLY SURFACE FLOW...WITH MAX TEMPS
EXPECTED TO REACH ONLY THE MID 70S FAR NW...TO MID 80S NEAR THE
SOUTH SANTEE RIVER. THE AFOREMENTIONED WAA WILL DRIVE HIGHS INTO THE
LOW/MID 80S CWA-WIDE ON MONDAY. LOWS SUNDAY NIGHT WILL DROP TO
NEAR-NORMAL LEVELS OF THE MID 60S...BUT WILL BE SEVERAL DEGREES
WARMER MONDAY NIGHT AHEAD OF THE NEXT COLD FRONT.
&&
.LONG TERM /TUESDAY THROUGH FRIDAY/...
AS OF 300 SATURDAY...STRONG COLD FRONT WILL PUSH ACROSS THE AREA ON
TUESDAY...USHERING IN COOL CANADIAN AIR FOR MOST OF THE UPCOMING
WEEK.
STRONG VORTICITY IMPULSE SPAWNING A SURFACE LOW PRESSURE WILL BE
RACING EAST WELL NORTH OF THE AREA...BUT A STRONG COLD FRONT BEHIND
THIS WILL DRAG ACROSS THE CWA DURING TUESDAY. A PERIOD OF UNSETTLED
WEATHER IS EXPECTED TUESDAY WITH SHOWERS AND THUNDERSTORMS...BUT
THIS FRONT SHOULD PUSH OFFSHORE BY WEDNESDAY AS A DEEP UPPER TROUGH
DIVES INTO THE EAST. THEREAFTER...GUIDANCE CONTINUES TO DIFFER ON
HOW FAR OFFSHORE THIS FRONT WILL STALL...WITH THE GFS CONTINUING TO
INDICATE THAT IT WILL BE JUST OFFSHORE AND CONTINUE UNSETTLED
CONDITIONS LOCALLY. THE ECMWF...WHICH IS PREFERRED...PUSHES THIS
FRONT WELL OFF THE COAST...WHICH SEEMS ACCURATE BASED OFF THE
STRENGTH OF THE UPPER TROUGH AND SINCE WE HAVE HAD SEVERAL FROPAS
ALREADY THIS YEAR.
USING THE ECMWF AS A GUIDE...WED-FRI WILL FEATURE
DRYING CONDITIONS AND TEMPS AROUND 5 DEGREES BELOW CLIMO THANKS TO
THE CANADIAN ORIGIN OF THE SURFACE HIGH RIDGING DOWN THE COAST. IN
ADDITION...IT APPEARS THE AREA WILL SEE SUNSHINE FOR THE FIRST TIME
IN SEVERAL DAYS BY WEDNESDAY. HOWEVER...MUST NOTE THE PERSISTENCE OF
THE GFS WHICH KEEPS THE FRONT JUST OFF THE COAST AND DEVELOPS A LOW
PRESSURE SYSTEM ALONG THE TAIL END OF THE BOUNDARY. THIS WOULD KEEP
UNSETTLED CONDITIONS ACROSS THE AREA...ESPECIALLY NEAR THE
COAST...WITH MORE WET WEATHER POSSIBLE LATE IN THE WEEK.
WILL KEEP INHERITED LOW-CHC/SCHC POP FOR POTENTIAL...BUT WITH A
SLIGHT DECREASE IN SPECIFIC VALUES TO ACCOUNT FOR THE MUCH DRIER
ECMWF.
&&
.AVIATION /10Z SATURDAY THROUGH WEDNESDAY/...
AS OF 06Z...STRATIFORM LIGHT RAIN NEAR KILM SHOULD DISSIPATE
OVER THE NEXT SEVERAL HOURS...ALTHOUGH THE HRRR MODEL SUGGESTS
ISOLATED CONVECTIVE SHOWERS WILL RE-DEVELOP EARLY THIS MORNING
ACROSS THE AREA. EXPECT THICK MID/UPPER CLOUD COVER THROUGH THE TAF
VALID PERIOD WITH COPIOUS AMOUNTS OF LOW LEVEL MOISTURE. IFR/LIFR
CONDITIONS WILL DEVELOP THIS MORNING KLBT/KILM/FLO WITH HIGHEST
CONFIDENCE AT KLBT/KILM WHICH IS NEAREST A STATIONARY FRONT.
KCRE/KMYR ARE MORE LIKELY TO EXPERIENCE MVFR CONDITIONS THIS
MORNING. ANY IFR IMPROVES TO MVFR FAIRLY QUICKLY AFTER SUNRISE WITH
VFR DEVELOPING MID-LATE MORNING. CLOUD COVER SHOULD INITIALLY
INHIBIT HEATING AND LIFT SO THINK WORSE CASE VCSH COASTAL TERMINALS
IN THE MORNING HOURS. BY AFTERNOON THUNDERSTORM POTENTIAL SHOULD BE
GREATEST AT KLBT. THIS POTENTIAL SHOULD SHIFT SE-E TO KFLO AND THE
THE COASTAL TERMINALS IN THE LATE AFTERNOON/EARLY EVENING.
EXTENDED OUTLOOK...A CHANCE OF SHOWERS WITH MAINLY AFTERNOON
THUNDERSTORMS/TEMPO MVFR THROUGH TUESDAY.
&&
.MARINE...
NEAR TERM/THROUGH TONIGHT/...
AS OF 600 AM SATURDAY...WINDS AND TO A LESSER DEGREE SIGNIFICANT
SEAS...WILL BE GOVERNED BY THE MEANDERING FRONTAL BOUNDARY DURING
THIS PERIOD. THIS MEANS...WATERS NORTH OF THE FRONT WILL OBSERVE
NE-E WINDS...AND SOUTH OF THE FRONT WILL SEE SE-SSW WINDS. THE
SFC PG REMAINS LOOSE FOR THE MOST PART RESULTING WITH WIND SPEEDS
AROUND 10 KT. HOWEVER...DEPENDING ON YOUR LOCATION BEHIND THE
FRONT...THE NE-E WINDS THAT OCCUR COULD PRODUCE SPEEDS UP TO 15
KT IF THE SFC PG TIGHTENS ENOUGH. SIGNIFICANT SEAS WILL REMAIN
DOCILE...AROUND 2 FT. THE MINI NE-E INCREASED WINDS BEHIND THE
FRONT COULD PRODUCE SIG. SEAS UP TO 3 FT. AVERAGE PERIODS WILL RUN
4 TO 5 SECONDS.
SHORT TERM /SUNDAY THROUGH MONDAY NIGHT/...
AS OF 300 AM SATURDAY...COLD FRONT SOUTH OF THE WATERS TO START THE
PERIOD WILL REMAIN NEARLY STATIONARY SUNDAY...BEFORE LIFTING BACK TO
THE NORTH AS A WARM FRONT MONDAY. THIS DRIVES NE WINDS ALL SUNDAY
AND INTO MONDAY...BEFORE VEERING TO BECOME S/SE LATE ON MONDAY.
SPEEDS WILL BE 5-10 KTS REGARDLESS OF DIRECTION. A COLD FRONT WILL
APPROACH AT THE VERY END OF THE SHORT TERM WITH WINDS BEGINNING TO
VEER TO THE WEST LATE MONDAY NIGHT. SEAS WILL BE 1-3 FT THROUGH THE
PERIOD...WITH A NE WIND WAVE PREDOMINANT ON SUNDAY...BECOMING
SOUTHERLY DURING MONDAY.
LONG TERM /TUESDAY THROUGH WEDNESDAY/...
AS OF 300 AM SATURDAY...THE BEGINNING OF AN EXTENDED PERIOD OF POOR
MARINE CONDITIONS EXPECTED TUESDAY AS A COLD FRONT CROSSES THE
WATERS. ALTHOUGH WINDS TUESDAY WILL BE PRETTY LIGHT...5-10 KTS WITH
SEVERAL VEERING WIND DIRECTIONS...THE CONFUSED SPECTRUM WILL COMBINE
WITH THE SLOWLY AMPLIFYING LONG PERIOD 13-14 SEC SE SWELL ASSOCIATED
WITH TROPICAL STORM EDOUARD MOVING THROUGH THE CENTRAL ATLANTIC...TO
DRIVE INCREASING WAVE HEIGHTS. ADDITIONALLY...A NE SURGE WILL BEGIN
TUESDAY NIGHT BEHIND THIS BOUNDARY...WITH NE WINDS RISING TO AROUND
15 KTS ON WEDNESDAY.
THE COMBINATION OF THE LONG-PERIOD SWELL AND INCREASING WINDS WILL
DRIVE WAVE HEIGHTS FROM 2-4 FT TUESDAY TO 4-6 FT WEDNESDAY...AND A
SMALL CRAFT ADVISORY WILL LIKELY BE NEEDED BEGINNING WEDNESDAY.
ALTHOUGH IT IS BEYOND THIS PERIOD...IT APPEARS WEDNESDAY COULD BE
THE FIRST OF SEVERAL CONSECUTIVE DAYS WITH HEADLINES NEEDED ACROSS
THE COASTAL WATERS.
&&
.ILM WATCHES/WARNINGS/ADVISORIES...
SC...FLOOD WATCH THROUGH LATE TONIGHT FOR SCZ017-023-024-032-033-
039-053>056.
NC...FLOOD WATCH THROUGH LATE TONIGHT FOR NCZ087-096-099-105>110.
MARINE...NONE.
&&
$$
SYNOPSIS...JDW
NEAR TERM...DCH
SHORT TERM...JDW
LONG TERM...JDW
AVIATION...DCH/MRR
MARINE...
AREA FORECAST DISCUSSION
NWS GRAND FORKS ND
1021 AM CDT SAT SEP 13 2014
.UPDATE...
ISSUED AT 1017 AM CDT SAT SEP 13 2014
FCST GOING AS PLANNED...HIGH AND MID LEVEL CLOUDS OVER THE FCST
AREA IN AREA OF 850 MB WARM ADVECTION. 925 MB WINDS IN THE 25-30
KT RANGE 15-21Z WILL START TO GET TO THE SURFACE AS TEMPS WARM.
MAIN SFC LOW WEST OF BRANDON MANITOBA...MOVING EAST. RAIN SHOWERS
MOSTLY ASSOC WITH UPPER LOW JUST NORTH OF REGINA SK AND MODELS
CONTINUE TO KEEP MOST OF THE PRECIP WITH THIS EVENT JUST NORTH OF
THE BORDER TONIGHT THEN OVER LAKE OF THE WOODS REGION AND ONTARIO
SUNDAY. WILL CONTINUE WITH LOWER POPS SOUTH OF LOW WITH HRRR
SHOWING SOME SHOWERS LATER AFTN-EVE MOVING INTO NE ND/NRN RRV.
&&
.SHORT TERM...(TODAY THROUGH SUNDAY)
ISSUED AT 338 AM CDT SAT SEP 13 2014
NO CHANGE IN THE CURRENT FROST ADVISORY...ALTHOUGH A FEW LOCATIONS
OVER THE FAR EASTERN CWFA ARE IN THE MID 20S AT 08Z. WITH CIRRUS
INCREASING AND RETURN FLOW DEVELOPING DO NOT EXPECT TEMPERATURES
TO FALL MORE THAN 1 OR 2 DEGREES IN THE KVWU...KBJI...KBDO AND
KADC AREAS.
TODAY WILL BE A TRANSITION DAY. AS THE UNSEASONALLY COLD HIGH
MOVES SOUTH...LOW PRESSURE INTENSIFIES OVER SASKATCHEWAN SOUTH
WINDS WILL INCREASE BY MID DAY. THE MODELS INITIALIZED WELL AND
WILL FOLLOW THE HIGHER RESOLUTION HRRR AND NAM12 TODAY...BLENDING
THE NAM/GFS FOR TONIGHT INTO SUNDAY MORNING. TIMING OF WARM
ADVECTION PRECIPITATION AHEAD OF WELL DEFINED UPPER WAVE OVER
FAR NORTH-CENTRAL MONTANA SIMILAR TO PREVIOUS FORECAST REACHING THE
DEVILS LAKE BASIN AROUND 18Z AND SPREADING EAST. NAM/GFS HAVE
SMALL AREA OF 0C SHOWALTERS AND SOME ML CAPE BUT WILL NOT MENTION
TSRA ATTM. WITH WELL MIXED LAYER TO AROUND 800 MB...35 KTS AT 850
IN THE NAM AND NEAR 30 KTS IN THE GFS TRANSLATE TO GUSTS CLOSE TO
30 KTS POSSIBLE. MOS HAS 27 KTS AND WILL FOLLOW THAT FOR THE 18Z -
00Z PERIOD.
SECOND STRONGER SHORTWAVE...DROPPING ALONG THE ALBERTA/SASKATCHEWAN
BORDER IS FORECAST TO BE NEAR KDVL AT 06Z TONIGHT. SURFACE LOW
SLOWS AND WRAP AROUND SHRA SPREADING OVER THE EAST HALF OF THE
CWFA INTO SUNDAY MORNING.
THE COLUMN COOLS AND DRIES MOST AREAS SUNDAY...WITH LINGERING SHRA
OVER THE NORTHEAST PORTION OF THE CWFA...WITH STRONGER MID-UPPER
CAA ALONG SHEAR AXIS AND ENTRANCE REGION OF UPPER JET. THIS
QUICKLY MOVES OUT WITH PRECIPITATION ENDING BY 00Z MONDAY.
.LONG TERM...(SUNDAY NIGHT THROUGH FRIDAY)
ISSUED AT 338 AM CDT SAT SEP 13 2014
WINDS DIMINISH AND SKIES CLEAR AS HIGH PRESSURE MOVES ACROSS THE
CWFA. LOWS WILL FALL BACK INTO THE LOW TO MID 30S...BUT EXPECT
SUFFICIENT MIXING AT THIS TIME TO KEEP FROST/FREEZE RISK MINIMAL
FOR MONDAY MORNING. LIGHT SOUTHWEST WINDS AND PLENTIFUL SUNSHINE WILL
ALLOW MODEST WARM-UP MONDAY TO NEAR MID SEPTEMBER NORMALS. RISING
HEIGHTS AND CONTINUED WESTERLY FLOW WILL MAKE FOR A MAINLY CLEAR
AND MILD MONDAY NIGHT.
TUESDAY TO FRIDAY...CONFLUENT NW FLOW ALOFT FOR MUCH OF THE WEEK
WITH A QUICK TRANSITIONING PERIOD THURSDAY INTO FRIDAY. AS A RESULT
DRY CONDITIONS EXPECTED WITH MODERATING TEMPS AS THICKNESSES
INCREASE WITH RIDGING OVER THE FA BY THURSDAY. BY THURSDAY PM OR
FRIDAY DEPENDING ON MODEL OF CHOICE...500MB SW FLOW AND 850MB LLJ
BRING INSTABILITY INTO FA FROM WEST TO EAST. WENT WITH A MOSTLY
SHRA AND ISO THUNDER FOR WX GRIDS AS SHOWALTERS DO BECOME NEGATIVE
AHEAD OF THE SFC TROUGH EXPECTED TO IMPACT THE NORTHERN PLAINS
TOWARDS THE END OF THE WEEK. TEMPERATURES ABOVE NORMAL THROUGH THE
WEEK CAN BE EXPECTED WITH SOME HUMIDITY POSSIBLE BY WEEKS END.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SUNDAY MORNING)
ISSUED AT 1133 AM CDT SAT SEP 13 2014
VFR CIG/VSBY THROUGH THIS PERIOD...WITH INCRG SOUTH WINDS. BY 16Z
EXPECT G25KTS MOST TAF SITES. WSHFT FCST AT KDVL ABT 22Z. WDLY SCT
-SHRA PSBL AFT 18Z...BUT INSUFFICIENT CONFIDENCE TO PUT IN TAF
ATTM. -SHRA MOST LIKELY KDVL...KGFK...KTVF LINE AFT 21Z.
&&
.FGF WATCHES/WARNINGS/ADVISORIES...
ND...NONE.
MN...NONE.
&&
$$
UPDATE...RIDDLE
SHORT TERM...EWENS
LONG TERM...JK/EWENS
AVIATION...EWENS
AREA FORECAST DISCUSSION
NWS BISMARCK ND
854 AM CDT SAT SEP 13 2014
.UPDATE...
ISSUED AT 845 AM CDT SAT SEP 13 2014
CANCELLED THE FROST ADVISORY. REFINED THE CLOUD COVER BASED ON
SATELLITE TRENDS AS HIGH CLOUDS ARE FADING A BIT CENTRAL. UPPED
THE WINDS A BIT AFTER THE FRONTAL PASSAGE.
UPDATE ISSUED AT 633 AM CDT SAT SEP 13 2014
LATEST SURFACE ANALYSIS SHOWS SURFACE CDFNT OVER WESTERN NORTH
DAKOTA WITH STRATOCU DECK DROPPING SOUTH FROM ALBERTA AND WESTERN
SASKATCHEWAN INTO NORTH CENTRAL MONTANA. LATEST 10 UTC RAP LOOKS
TO BE A LITTLE TOO QUICK IN BRINGING HIGHER 850 MB MOISTURE INTO
WESTERN NORTH DAKOTA...BUT BASED ON LATEST SATELLITE AND
OBSERVATIONS HAVE BUMPED UP SKY COVER ACROSS THE WEST LATER THIS
MORNING AND OVER THE NORTH AND CENTRAL THIS AFTERNOON. NO CHANGES
TO POPS AT THIS TIME...KEEPING SLIGHT CHANCE MAINLY NORTH OF THE
I94 CORRIDOR...WHICH IS IN AGREEMENT WITH LATEST RAP/HRRR
ITERATIONS. CURRENT TEMPERATURES REMAIN IN THE MID 30S ACROSS MOST
OF THE FROST ADVISORY AREA...THUS WILL KEEP IT GOING.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 308 AM CDT SAT SEP 13 2014
EARLY MORNING WATER VAPOR IMAGERY SHOWED AN UPPER WAVE MOVING
SOUTHEAST ACROSS SOUTHERN SASKATCHEWAN WHICH WAS PUSHING A COLD
FRONT TOWARDS THE STATE. THE UPPER WAVE IS EXPECTED TO MOVE
QUICKLY ACROSS THE NORTHERN PLAINS TODAY ALONG WITH THE COLD
FRONT. THE MAIN QUESTION WILL BE HOW FAR SOUTH TO BRING A CHANCE
OF RAIN SHOWERS TODAY AS THE WAVE / COLD FRONT PASS. THERE ARE A
WIDE VARIETY OF MODEL SOLUTIONS WITH DIFFERING PLACEMENT...BUT DUE
TO THE STRENGTH OF THE WAVE OPTED TO FAVOR THE MODELS WHICH BRING
THE RAIN CHANCES FARTHER SOUTH INTO NORTH DAKOTA. IN FACT...AM A
BIT CONCERNED WE MAY NOT HAVE TAKEN THE POPS FAR ENOUGH SOUTH IF
THE 4.0KM WRF NMM VERIFIES. A POTENTIAL LIMITING FACTOR COULD BE
DRY AIR IN THE LOW LEVELS...SO KEPT THE RAIN CHANCES GENERALLY
NORTH OF I-94.
THE NEXT CONCERN SURROUNDS THE FROST ADVISORY WHICH IS IN PLACE
ACROSS ROUGHLY THE SOUTHERN HALF OF THE FORECAST AREA THIS
MORNING. PASSING HIGH CLOUDS AHEAD OF THE UPPER WAVE HAVE
HELPED TEMPERATURES RISE A FEW DEGREES OVERNIGHT IN SOME
LOCATIONS...BUT READINGS IN THE ADVISORY AREA REMAIN IN THE 30S
TO LOWER 40S. THE HIGH CLOUDS ARE RATHER THIN ON THEIR SOUTHERN
EDGE...AND WITH GFS LAMP GUIDANCE STILL SUPPORTING FALLING
TEMPERATURES AT MOST LOCATIONS...WILL KEEP THE ADVISORY IN PLACE.
.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 308 AM CDT SAT SEP 13 2014
THE LONG TERM PERIOD BEGINNING SUNDAY LOOKS RATHER TRANQUIL THROUGH
MID WEEK. PATCHY MORNING FROST CAN NOT BE RULED OUT EARLY SUNDAY AND
MONDAY MORNINGS WITH SURFACE HIGH PRESSURE OVER THE AREA AND A
NORTHWEST UPPER FLOW KEEPING SEASONABLY COOL AIR OVER THE NORTHERN
PLAINS. OTHERWISE IT LOOKS DRY WITH A WARMING TREND THROUGH MIDWEEK.
MORNING LOWS IN THE MID 30S TO LOWER 40S...AND DAYTIME HIGHS IN
THE UPPER 50S AND 60S SUNDAY AND MONDAY...WILL WARM TO THE MID 40S
TO MID 50S FOR LOWS...AND 70S FOR HIGHS BY MID TO LATE WEEK.
A PROGRESSIVE UPPER LEVEL TROUGH MOVING ONTO THE WESTERN U.S. COAST
ON THURSDAY WILL APPROACH THE NORTHERN PLAINS BY LATE FRIDAY.
THERE ARE DIFFERENCES IN THE HANDLING OF THIS WAVE BETWEEN THE GFS
AND ECMWF MODELS BUT BOTH BRING INCREASING MOISTURE AND A SMALL
CHANCE OF SHOWERS AND ISOLATED THUNDER LATE THURSDAY INTO EARLY
FRIDAY...WITH THE BEST CHANCE OF SHOWERS AND THUNDERSTORMS FRIDAY
AND FRIDAY NIGHT AND POSSIBLY LINGERING IN THE EAST EARLY
SATURDAY.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SUNDAY MORNING)
ISSUED AT 845 AM CDT SAT SEP 13 2014
COLD FRONT WILL TRACK ACROSS THE STATE TODAY. WIDELY SCATTERED
SHOWERS NORTH. VFR EXPECTED TO CONTINUE. CEILINGS AS LOW AS 35
HUNDRED AGL KDIK-KISN-KMOT...5 THOUSAND AGL OR GREATER BIS-KJMS.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...WAA
SHORT TERM...CK
LONG TERM...TWH
AVIATION...WAA
AREA FORECAST DISCUSSION
NWS GRAND FORKS ND
707 AM CDT SAT SEP 13 2014
.UPDATE...
ISSUED AT 705 AM CDT SAT SEP 13 2014
MINIMAL CHANGES THIS UPDATE. TWEAKED WIND GUST TIMING SLIGHTLY
BASED ON 88D VWP 925MB WINDS...HRRR AND NAM12 SFC WIND FCST. LATER
SHIFTS WILL NEED TO REFINE TIMING OF -SHRA AND AREAL COVERAGE.
OTRW FROST ADVISORY EXP 13Z.
&&
.SHORT TERM...(TODAY THROUGH SUNDAY)
ISSUED AT 338 AM CDT SAT SEP 13 2014
NO CHANGE IN THE CURRENT FROST ADVISORY...ALTHOUGH A FEW LOCATIONS
OVER THE FAR EASTERN CWFA ARE IN THE MID 20S AT 08Z. WITH CIRRUS
INCREASING AND RETURN FLOW DEVELOPING DO NOT EXPECT TEMPERATURES
TO FALL MORE THAN 1 OR 2 DEGREES IN THE KVWU...KBJI...KBDO AND
KADC AREAS.
TODAY WILL BE A TRANSITION DAY. AS THE UNSEASONALLY COLD HIGH
MOVES SOUTH...LOW PRESSURE INTENSIFIES OVER SASKATCHEWAN SOUTH
WINDS WILL INCREASE BY MID DAY. THE MODELS INITIALIZED WELL AND
WILL FOLLOW THE HIGHER RESOLUTION HRRR AND NAM12 TODAY...BLENDING
THE NAM/GFS FOR TONIGHT INTO SUNDAY MORNING. TIMING OF WARM
ADVECTION PRECIPITATION AHEAD OF WELL DEFINED UPPER WAVE OVER
FAR NORTH-CENTRAL MONTANA SIMILAR TO PREVIOUS FORECAST REACHING THE
DEVILS LAKE BASIN AROUND 18Z AND SPREADING EAST. NAM/GFS HAVE
SMALL AREA OF 0C SHOWALTERS AND SOME ML CAPE BUT WILL NOT MENTION
TSRA ATTM. WITH WELL MIXED LAYER TO AROUND 800 MB...35 KTS AT 850
IN THE NAM AND NEAR 30 KTS IN THE GFS TRANSLATE TO GUSTS CLOSE TO
30 KTS POSSIBLE. MOS HAS 27 KTS AND WILL FOLLOW THAT FOR THE 18Z -
00Z PERIOD.
SECOND STRONGER SHORTWAVE...DROPPING ALONG THE ALBERTA/SASKATCHEWAN
BORDER IS FORECAST TO BE NEAR KDVL AT 06Z TONIGHT. SURFACE LOW
SLOWS AND WRAP AROUND SHRA SPREADING OVER THE EAST HALF OF THE
CWFA INTO SUNDAY MORNING.
THE COLUMN COOLS AND DRIES MOST AREAS SUNDAY...WITH LINGERING SHRA
OVER THE NORTHEAST PORTION OF THE CWFA...WITH STRONGER MID-UPPER
CAA ALONG SHEAR AXIS AND ENTRANCE REGION OF UPPER JET. THIS
QUICKLY MOVES OUT WITH PRECIPITATION ENDING BY 00Z MONDAY.
.LONG TERM...(SUNDAY NIGHT THROUGH FRIDAY)
ISSUED AT 338 AM CDT SAT SEP 13 2014
WINDS DIMINISH AND SKIES CLEAR AS HIGH PRESSURE MOVES ACROSS THE
CWFA. LOWS WILL FALL BACK INTO THE LOW TO MID 30S...BUT EXPECT
SUFFICIENT MIXING AT THIS TIME TO KEEP FROST/FREEZE RISK MINIMAL
FOR MONDAY MORNING. LIGHT SOUTHWEST WINDS AND PLENTIFUL SUNSHINE WILL
ALLOW MODEST WARM-UP MONDAY TO NEAR MID SEPTEMBER NORMALS. RISING
HEIGHTS AND CONTINUED WESTERLY FLOW WILL MAKE FOR A MAINLY CLEAR
AND MILD MONDAY NIGHT.
TUESDAY TO FRIDAY...CONFLUENT NW FLOW ALOFT FOR MUCH OF THE WEEK
WITH A QUICK TRANSITIONING PERIOD THURSDAY INTO FRIDAY. AS A RESULT
DRY CONDITIONS EXPECTED WITH MODERATING TEMPS AS THICKNESSES
INCREASE WITH RIDGING OVER THE FA BY THURSDAY. BY THURSDAY PM OR
FRIDAY DEPENDING ON MODEL OF CHOICE...500MB SW FLOW AND 850MB LLJ
BRING INSTABILITY INTO FA FROM WEST TO EAST. WENT WITH A MOSTLY
SHRA AND ISO THUNDER FOR WX GRIDS AS SHOWALTERS DO BECOME NEGATIVE
AHEAD OF THE SFC TROUGH EXPECTED TO IMPACT THE NORTHERN PLAINS
TOWARDS THE END OF THE WEEK. TEMPERATURES ABOVE NORMAL THROUGH THE
WEEK CAN BE EXPECTED WITH SOME HUMIDITY POSSIBLE BY WEEKS END.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SUNDAY MORNING)
ISSUED AT 1133 AM CDT SAT SEP 13 2014
VFR CIG/VSBY THROUGH THIS PERIOD...WITH INCRG SOUTH WINDS. BY 16Z
EXPECT G25KTS MOST TAF SITES. WSHFT FCST AT KDVL ABT 22Z. WDLY SCT
-SHRA PSBL AFT 18Z...BUT INSUFFICIENT CONFIDENCE TO PUT IN TAF
ATTM. -SHRA MOST LIKELY KDVL...KGFK...KTVF LINE AFT 21Z.
&&
.FGF WATCHES/WARNINGS/ADVISORIES...
ND...FROST ADVISORY UNTIL 8 AM CDT THIS MORNING FOR NDZ030-039-049-
052-053.
MN...FROST ADVISORY UNTIL 8 AM CDT THIS MORNING FOR MNZ001>003-005-
006-008-009-013>017-022>024-027>032-040.
&&
$$
UPDATE...EWENS
SHORT TERM...EWENS
LONG TERM...JK/EWENS
AVIATION...EWENS
AREA FORECAST DISCUSSION
NWS BISMARCK ND
634 AM CDT SAT SEP 13 2014
.UPDATE...
ISSUED AT 633 AM CDT SAT SEP 13 2014
LATEST SURFACE ANALYSIS SHOWS SURFACE CDFNT OVER WESTERN NORTH
DAKOTA WITH STRATOCU DECK DROPPING SOUTH FROM ALBERTA AND WESTERN
SASKATCHEWAN INTO NORTH CENTRAL MONTANA. LATEST 10 UTC RAP LOOKS
TO BE A LITTLE TOO QUICK IN BRINGING HIGHER 850 MB MOISTURE INTO
WESTERN NORTH DAKOTA...BUT BASED ON LATEST SATELLITE AND
OBSERVATIONS HAVE BUMPED UP SKY COVER ACROSS THE WEST LATER THIS
MORNING AND OVER THE NORTH AND CENTRAL THIS AFTERNOON. NO CHANGES
TO POPS AT THIS TIME...KEEPING SLIGHT CHANCE MAINLY NORTH OF THE
I94 CORRIDOR...WHICH IS IN AGREEMENT WITH LATEST RAP/HRRR
ITERATIONS. CURRENT TEMPERATURES REMAIN IN THE MID 30S ACROSS MOST
OF THE FROST ADVISORY AREA...THUS WILL KEEP IT GOING.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 308 AM CDT SAT SEP 13 2014
EARLY MORNING WATER VAPOR IMAGERY SHOWED AN UPPER WAVE MOVING
SOUTHEAST ACROSS SOUTHERN SASKATCHEWAN WHICH WAS PUSHING A COLD
FRONT TOWARDS THE STATE. THE UPPER WAVE IS EXPECTED TO MOVE
QUICKLY ACROSS THE NORTHERN PLAINS TODAY ALONG WITH THE COLD
FRONT. THE MAIN QUESTION WILL BE HOW FAR SOUTH TO BRING A CHANCE
OF RAIN SHOWERS TODAY AS THE WAVE / COLD FRONT PASS. THERE ARE A
WIDE VARIETY OF MODEL SOLUTIONS WITH DIFFERING PLACEMENT...BUT DUE
TO THE STRENGTH OF THE WAVE OPTED TO FAVOR THE MODELS WHICH BRING
THE RAIN CHANCES FARTHER SOUTH INTO NORTH DAKOTA. IN FACT...AM A
BIT CONCERNED WE MAY NOT HAVE TAKEN THE POPS FAR ENOUGH SOUTH IF
THE 4.0KM WRF NMM VERIFIES. A POTENTIAL LIMITING FACTOR COULD BE
DRY AIR IN THE LOW LEVELS...SO KEPT THE RAIN CHANCES GENERALLY
NORTH OF I-94.
THE NEXT CONCERN SURROUNDS THE FROST ADVISORY WHICH IS IN PLACE
ACROSS ROUGHLY THE SOUTHERN HALF OF THE FORECAST AREA THIS
MORNING. PASSING HIGH CLOUDS AHEAD OF THE UPPER WAVE HAVE
HELPED TEMPERATURES RISE A FEW DEGREES OVERNIGHT IN SOME
LOCATIONS...BUT READINGS IN THE ADVISORY AREA REMAIN IN THE 30S
TO LOWER 40S. THE HIGH CLOUDS ARE RATHER THIN ON THEIR SOUTHERN
EDGE...AND WITH GFS LAMP GUIDANCE STILL SUPPORTING FALLING
TEMPERATURES AT MOST LOCATIONS...WILL KEEP THE ADVISORY IN PLACE.
.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 308 AM CDT SAT SEP 13 2014
THE LONG TERM PERIOD BEGINNING SUNDAY LOOKS RATHER TRANQUIL THROUGH
MID WEEK. PATCHY MORNING FROST CAN NOT BE RULED OUT EARLY SUNDAY AND
MONDAY MORNINGS WITH SURFACE HIGH PRESSURE OVER THE AREA AND A
NORTHWEST UPPER FLOW KEEPING SEASONABLY COOL AIR OVER THE NORTHERN
PLAINS. OTHERWISE IT LOOKS DRY WITH A WARMING TREND THROUGH MIDWEEK.
MORNING LOWS IN THE MID 30S TO LOWER 40S...AND DAYTIME HIGHS IN
THE UPPER 50S AND 60S SUNDAY AND MONDAY...WILL WARM TO THE MID 40S
TO MID 50S FOR LOWS...AND 70S FOR HIGHS BY MID TO LATE WEEK.
A PROGRESSIVE UPPER LEVEL TROUGH MOVING ONTO THE WESTERN U.S. COAST
ON THURSDAY WILL APPROACH THE NORTHERN PLAINS BY LATE FRIDAY.
THERE ARE DIFFERENCES IN THE HANDLING OF THIS WAVE BETWEEN THE GFS
AND ECMWF MODELS BUT BOTH BRING INCREASING MOISTURE AND A SMALL
CHANCE OF SHOWERS AND ISOLATED THUNDER LATE THURSDAY INTO EARLY
FRIDAY...WITH THE BEST CHANCE OF SHOWERS AND THUNDERSTORMS FRIDAY
AND FRIDAY NIGHT AND POSSIBLY LINGERING IN THE EAST EARLY
SATURDAY.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SUNDAY MORNING)
ISSUED AT 633 AM CDT SAT SEP 13 2014
A COLD FRONT WILL MOVE ACROSS NORTH DAKOTA TODAY. THIS WILL BRING
GUSTY WEST / NORTHWEST WINDS WITH INCREASING CLOUDS. HAVE KEPT
CEILINGS VFR FOR NOW...BUT COULD SEE THE POTENTIAL FOR
MVFR...ESPECIALLY AT KISN AND KMOT. WINDS DIMINISH SATURDAY EVENING
AS SURFACE HIGH PRESSURE BUILDS INTO WESTERN NORTH DAKOTA. CLOUDS
SHOULD DIMINISH SOUTH AND WEST...BUT THEY MAY LINGER ESPECIALLY
TOWARDS KMOT. A FEW RAIN SHOWERS ARE ALSO EXPECTED TODAY...BUT DID
NOT PUT THEM INTO THE TAF FOR NOW.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
FROST ADVISORY UNTIL 9 AM CDT /8 AM MDT/ THIS MORNING FOR NDZ020-
025-033>037-040>048-050-051.
&&
$$
UPDATE...TWH
SHORT TERM...CK
LONG TERM...TWH
AVIATION...CK
AREA FORECAST DISCUSSION
NWS NORMAN OK
1037 AM CDT SAT SEP 13 2014
.DISCUSSION...
PERSISTENT CLOUD COVER WILL MAINTAIN RELATIVELY COOL WEATHER INTO
THE AFTERNOON OVER MOST OF OKLAHOMA AND NORTH TEXAS. CURRENT
SATELLITE TRENDS APPEAR TO SUPPORT THE HRRR MODEL FORECAST OF
CLOUD BREAKUP THIS AFTERNOON...EARLIER IN PARTS OF NORTHERN
OKLAHOMA...WHERE THERE ARE ALREADY LARGE HOLES IN THE CLOUD COVER.
THE FORECAST WAS UPDATED EARLIER THIS MORNING TO ACCOUNT FOR THE
LATEST TRENDS AND EXPECTATIONS.
&&
.PREV DISCUSSION... /ISSUED 638 AM CDT SAT SEP 13 2014/
AVIATION...
13/12Z TAFS...MVFR CIGS WILL BE SEEN AT MOST TERMINALS THROUGH
ABOUT 15-17Z...WITH VFR EXPECTED THEREAFTER. NORTHERLY WINDS WILL
BECOME SOUTHEAST LATE TODAY AND INCREASE IN SPEED AFTER THIS
FORECAST PERIOD. LOW CLOUDS WILL BEGIN TO INCREASE TOWARD END OF
FORECAST PERIOD BUT WILL LEAVE FCST VFR FOR NOW.
PREV DISCUSSION... /ISSUED 410 AM CDT SAT SEP 13 2014/
DISCUSSION...
CLEARING...AT LEAST PARTIALLY...EXPECTED THE REGION TODAY. THE
GREATEST AMOUNT OF CLEARING EXPECTED OVER THE NORTH-CENTRAL
PORTIONS OF OKLAHOMA. SOUTHERN OKLAHOMA AND WESTERN NORTH TEXAS
MAY ACTUALLY SEE MORE CLOUDS THAN SUN TODAY. NO PRECIPITATION
EXPECTED TODAY OR TONIGHT.
RETURN TO SOUTHERLY FLOW TONIGHT AND SUNDAY WILL ALLOW MOISTURE
TO WORK ITS WAY BACK OVER REGION AND ALLOW CLOUDS TO FILL BACK IN
ON SUNDAY. RAIN CHANCES RETURN TO FORECAST SUNDAY NIGHT AS NEXT
UPPER LEVEL TROUGH AND ASSOCIATED COLD FRONT MOVE OVER SOUTHERN
PLAINS. MOST OF THE PRECIP EXPECTED NEAR THE FRONT AS IT
PROGRESSES SLOWLY SOUTH OVER OKLAHOMA TO THE RED RIVER VALLEY
MONDAY AFTERNOON AND MONDAY NIGHT. FRONT LIFTS BACK NORTH TUESDAY
INTO WEDNESDAY...AND WITH DEVELOPMENT OF NWLY FLOW...WILL BE A
FOCUS FOR SHOWERS AND STORMS WEDNESDAY INTO THURSDAY MAINLY OVER
THE EASTERN HALF OF OKLAHOMA. CONFIDENCE NOT QUITE AS HIGH SO POPS
WILL REMAIN ON THE LOW SIDE OF GUIDANCE. FAIR AMOUNT OF DISPARITY
IN THE MEDIUM RANGE MODELS FOR FRIDAY AND NEXT WEEKEND...WITH ECM
CURRENTLY SHOWING PROLONGED PERIOD OF RAIN AND GFS A MORE
PROGRESSIVE AND DRY PATTERN. TRENDS WILL NEED TO BE MONITORED
BEFORE POPS ARE INTRODUCED AT END OF FORECAST PERIOD.
&&
.PRELIMINARY POINT TEMPS/POPS...
OKLAHOMA CITY OK 66 57 80 66 / 0 0 10 20
HOBART OK 70 55 80 65 / 0 0 10 20
WICHITA FALLS TX 67 59 81 68 / 10 0 10 10
GAGE OK 71 53 82 63 / 0 0 10 10
PONCA CITY OK 67 53 79 65 / 0 0 10 20
DURANT OK 68 60 78 66 / 10 0 10 10
&&
.OUN WATCHES/WARNINGS/ADVISORIES...
OK...NONE.
TX...NONE.
&&
$$
23/17
AREA FORECAST DISCUSSION
NWS PHOENIX AZ
350 PM MST SAT SEP 13 2014
.SYNOPSIS...
AN INCREASE IN MOISTURE FROM THE EAST WILL MAINTAIN A SLIGHT CHANCE
THUNDERSTORMS THROUGH MONDAY. DEEPER TROPICAL MOISTURE WILL BEGIN TO
MOVE IN TUESDAY FOR A SIGNIFICANT INCREASE IN STORM CHANCES THE REST
OF NEXT WEEK.
&&
.DISCUSSION...
REST OF TODAY THROUGH MONDAY...
TIGHT SURFACE PRESSURE GRADIENT ACROSS ARIZONA AND NEW MEXICO WITH
LOWER PRESSURE OVER THE MOHAVE DESERT AND HIGH PRESSURE OVER THE
PLAINS. THIS IS DUE TO A BACK DOOR COLD FRONT SPILLING OVER THE
SOUTHERN CONTINENTAL DIVIDE. BREEZY EASTERLY WINDS HAVE RESULTED AS
HAVE HIGHER DEW POINTS AND COOLER TEMPERATURES...MOST NOTICEABLY
OVER EASTERN PORTIONS OF OUR FORECAST AREA. THE INCREASED MOISTURE
HOWEVER LOOKS TO BE OFFSET BY AN INCREASE IN CIN...AT LEAST OVER
SOUTHERN ARIZONA. NCEP MODELS AS WELL AS HRRR AND LOCAL HI-RES
MODELS ARE NOT VERY ENTHUSIASTIC ABOUT STORM ACTIVITY THE REST OF
TODAY AND TONIGHT FOR OUR AREA. HOWEVER...WITH THE MOISTURE THERE IS
A SLIGHT CHANCE OF OUTFLOW FROM DISTANT STORMS KICKING OFF A
STORM...MAINLY EAST OF THE LOWER COLORADO RIVER VALLEY. FOR SUNDAY
AND MONDAY...THE MODELS AGREE ON THE IDEA OF A SLOW WARMING OF THE
BOUNDARY LAYER TO REDUCE THE CAP BUT NO INCREASE IN MOISTURE...EVEN
DECREASING A BIT. SO SLIGHT CHANCES CONTINUE. ONE DIFFERENCE MIGHT
BE FOR MONDAY AS AN ANTICYCLONE BECOMES CENTERED OVER SOUTHERN
NEVADA LEADING TO NORTHEASTERLY STEERING FLOW...PER GFS...WHICH
COULD AID THE ADVECTION OF MOGOLLON RIM STORMS INTO OUR HIGHER
TERRAIN ZONE EAST OF PHOENIX. THE PRESSURE GRADIENT CONTINUES SUNDAY
FOR MORE BREEZINESS BEFORE WEAKENING MONDAY. MEANWHILE...HURRICANE
ODILE CURRENTLY SEVERAL HUNDRED MILES SOUTH-SOUTHEAST OF THE
SOUTHERN TIP OF BAJA IS FORECAST TO MOVE NORTHWESTWARD WITH THE EYE
GETTING FAIRLY CLOSE TO CABO SAN LUCAS LATE SUNDAY NIGHT/EARLY
MONDAY MORNING.
TUESDAY THROUGH SATURDAY...
MODELS INDICATE SOMETHING OF A GULF SURGE...MOST LIKELY DRIVEN BY
HURRICANE ODILE...MOVING INTO OUR FORECAST AREA BY TUESDAY. POPS GO
UP A BIT DUE TO INCREASED MOISTURE AND GREATER LIKELIHOOD OF
MOUNTAIN STORMS BUT THERE MAY BE SOME BOUNDARY LAYER COOLING WHICH
HURTS INSTABILITY OVER THE LOWER ELEVATIONS. 12Z GFS AND ECMWF BEGIN
DIVERGING MORE NOTICEABLY IN THEIR POSITIONING OF ODILE AS WELL AS
THE ANTICYCLONE TO THE NORTH AND THE NORTHEAST PACIFIC TROUGH. THE
ECMWF IS A BIT MORE AMPLIFIED WITH THE FLOW AND HAS THE MID LATITUDE
ROSSBY WAVE A BIT FURTHER WEST WITH ODILE CLOSER TO THE BAJA COAST.
IT BRINGS REMNANTS OF ODILE INLAND BY FRIDAY. THE 12Z GFS TRACKS
ODILE FURTHER WEST. HOWEVER...THE GFS HAS A MORE DISTINCT SHORT WAVE
MOVING NORTHWARD INTO ARIZONA WEDNESDAY NIGHT AND THURSDAY BECAUSE
IT HAS THE ANTICYCLONE FURTHER EAST. THE NATIONAL HURRICANE CENTER
FORECAST IS CLOSER TO THE ECWMF POSITION. A QUICK LOOK AT THE 18Z
GFS SHOWS THAT IT NOW LOOKS A LOT MORE LIKE THE ECMWF. IN
SHORT...THEY BOTH ARE INDICATING THAT THE BEST CHANCES FOR STORMS
AND ASSOCIATED FLOODING POTENTIAL IS IN THE WEDNESDAY THROUGH FRIDAY
TIME FRAME. IT SHOULD BE NOTED THAT NEITHER MODEL HAS ESPECIALLY
IMPRESSIVE MODEL RUN TOTAL PRECIP ACCUMULATIONS CONSIDERING THE
ABUNDANT PRECIPITABLE WATER THAT WILL BE AVAILABLE. LIKEWISE WITH
THE WPC FORECASTS. FORECASTS REFLECT POPS THAT ARE SUBSTANTIALLY
ABOVE CLIMO ALONG WITH COOLER TEMPS. FAR TOO EARLY FOR FLASH FLOOD
WATCHES BUT WILL CONTINUE TO EVALUATE.
&&
.AVIATION...
SOUTH-CENTRAL ARIZONA INCLUDING KPHX...KIWA...KSDL...AND SOUTHEAST
CALIFORNIA AND SOUTHWEST ARIZONA...INCLUDING KIPL AND KBLH...
SCATTERED TO BROKEN CLOUD DECKS GENERALLY AOA 12KFT...AND WINDS
WILL CONTINUE TO FAVOR EAST-SOUTHEASTERLY DIRECTIONS AT ALL
TERMINALS THIS EVENING/OVERNIGHT INTO SUNDAY. EXPECT LOCAL GUSTS UP
TO 20KT OR SO AT TIMES...MAINLY BETWEEN 15Z AND 20Z SUNDAY. STORM
CHANCES ARE SLIGHT FOR THE DESERT ELEVATIONS...MORE FAVORED OVER
MOUNTAINS OF NORTHERN/EASTERN AZ DURING THE PERIOD. STILL POSSIBLE
TO HAVE OUTFLOW WINDS THIS EVENING - FROM 02Z TO 05Z - FROM ANY
DISTANT STORM...BUT SIGNIFICANT WIND SHIFTS ARE NOT INDICATED IN THE
TAF AT THIS TIME.
AVIATION DISCUSSION NOT UPDATED FOR AMENDED TAFS.
&&
.FIRE WEATHER...
TUESDAY THROUGH SATURDAY...
MOISTURE WILL STEADILY INCREASE ACROSS THE AREA DURING THE WEEK WITH
A NOTEWORTHY INCREASE IN HUMIDITIES TAKING PLACE ON WEDNESDAY.
SHOWERS WILL INCREASE IN COVERAGE WEDNESDAY NIGHT THROUGH FRIDAY
WITH SOME AREAS POTENTIALLY LOOKING AT PERIODS OF HEAVY RAINFALL. AS
SUCH...AFTERNOON HUMIDITIES WILL REMAIN ELEVATED WITH GOOD TO
EXCELLENT RECOVERIES EXPECTED. WINDS SHOULD BE LIGHT DURING THE WEEK
OUTSIDE OF THUNDERSTORM INDUCED OUTFLOWS.
&&
.PSR WATCHES/WARNINGS/ADVISORIES...
AZ...NONE.
CA...NONE.
&&
$$
VISIT US ON FACEBOOK...TWITTER...AND AT WEATHER.GOV/PHOENIX
DISCUSSION...AJ
AVIATION...MEYERS
FIRE WEATHER...MEYERS/LEINS
AREA FORECAST DISCUSSION
NWS MIAMI FL
348 PM EDT SAT SEP 13 2014
.DISCUSSION...
THE LATEST CONSENSUS OF THE MODEL GUIDANCE...BOTH THE GLOBAL
MODELS AND THE LATEST HRRR RUN...INDICATE THE POTENTIAL FOR
SHOWERS AND THUNDERSTORMS TO FORM ACROSS THE FLORIDA STRAITS THIS
EVENING AND AFFECT THE SOUTHERN PORTIONS OF SOUTH FLORIDA AND
ADJACENT WATERS LATER THIS EVENING AND POSSIBLY CONTINUING INTO
THE EARLY MORNING HOURS ON SUNDAY. RECENT SATELLITE IMAGERY AND
RADAR RETURNS INDICATE THIS PROCESS IS ALREADY UNDERWAY WITH BANDS
OF SHOWERS AND THUNDERSTORMS OBSERVED ACROSS THE FLORIDA STRAITS.
OVER NIGHT AND INTO SUNDAY...A BROAD AREA OF SURFACE LOW PRESSURE
ACROSS THE EASTERN GULF WILL CONTINUE TO TRACK WESTWARD INTO THE
CENTRAL GULF. THE MORE RECENT GUIDANCE HAS CONSISTENTLY BEEN
INDICATING THAT DEEP TROPICAL MOISTURE WILL CONTINUE TO LINGER
ACROSS SOUTH FLORIDA AND ADJACENT WATERS WITH LOW LEVEL MASS AND
MOISTURE CONVERGENCE CONTINUING ACROSS THE REGION INTO SUNDAY
MORNING. IN ADDITION THE UPPER LEVEL WINDS COULD BE FAVORABLE FOR
SPEED DIVERGENCE DURING THE AFTERNOON HOURS. DAY TIME HEATING AND
WITH THE LINGERING DEEP MOISTURE WILL ALLOW FOR AFTERNOON
CONVECTION ON SUNDAY WITH THE GREATEST COVERAGE OF SHOWERS AND
THUNDERSTORMS EXPECTED INLAND AND WEST.
FOR MONDAY AND TUESDAY...SOME RELATIVELY DRIER AIR IS FORECAST TO
ENTER THE REGION ALTHOUGH THE GUIDANCE CONSENSUS INDICATES THAT
LINGERING MOISTURE COULD BE SUFFICIENT FOR AFTERNOON SHOWERS AND
THUNDERSTORMS...MAINLY OVER THE THE PENINSULA. THE EXTENDED
GUIDANCE CONTINUES TO SUGGEST THAT LATE NEXT WEEK DEEP MOISTURE
COULD EXTEND FROM THE YUCATAN PENINSULA NORTHEASTWARD ACROSS SOUTH
FLORIDA AND INTO THE WESTERN ATLANTIC WITH A LARGE AMPLITUDE UPPER
LEVEL TROUGH DEEPENING INTO THE CENTRAL GULF. THIS PATTERN IS
FORECAST TO LINGER INTO NEXT WEEKEND WITH THE POTENTIAL FOR
WIDESPREAD LOCAL CONVECTION.
&&
.MARINE...
MAINLY EASTERLY WINDS ARE FORECAST TO BE IN THE 10 TO 15 KNOT
RANGE ACROSS THE REGIONAL WATERS TONIGHT THROUGH SUNDAY THEN
SLOWLY DECREASING INTO EARLY NEXT WEEK WHILE REMAINING EASTERLY.
REGIONAL SEAS ARE FORECAST TO BE MAINLY AROUND 2 FEET OR LESS THE
REMAINDER OF THE WEEKEND INTO EARLY NEXT WEEK.
&&
.PRELIMINARY POINT TEMPS/POPS...
WEST PALM BEACH 87 76 86 76 / 50 40 60 20
FORT LAUDERDALE 87 77 88 79 / 50 50 50 20
MIAMI 87 77 87 78 / 50 50 50 20
NAPLES 89 75 87 76 / 70 40 60 20
&&
.MFL WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
AM...NONE.
GM...NONE.
&&
$$
SHORT TERM...23/SK
LONG TERM....60/BD
AREA FORECAST DISCUSSION
NWS MIAMI FL
128 PM EDT SAT SEP 13 2014
.AVIATION...
SHOWERS WITH ISOLATED THUNDER ARE NOW DEVELOPING NEAR THE EAST
COAST TERMINALS, WITH ADDITIONAL DEVELOPMENT THROUGH THE ATLANTIC
WATERS. QUESTIONABLE IF EAST COAST TERMINALS WILL FALL BEHIND THE
SEA BREEZE, WITH ONLY SHOWERS THE REST OF TODAY, OR WILL CONTINUE
TO SEE ADDITIONAL DEVELOPMENT OF THUNDERSTORMS WITH A WEAK UPPER
DISTURBANCE CURRENTLY JUST WEST OF THE BAHAMAS. ALTHOUGH VCTS IS
IN THE TAFS, IT MAY BE REMOVED LATER IF STORMS DON`T FIRE.
THEREFORE, DID NOT INCLUDE ANY TEMPO GROUPS ATTM. FEELING MORE
CONFIDENT ABOUT DEVELOPMENT AT APF, AS SEA BREEZE/STORMS MOVE
ACROSS THE PENINSULA. LIKE LAST NIGHT, ACTUALLY EXPECTING MORE
COVERAGE OF SHOWERS AND STORMS OVERNIGHT AS EASTERLY FLOW
CONTINUES. ANOTHER STRONGER VORT MAX NEAR NASSAU WILL ARRIVE JUST
EAST OF BISCAYNE BAY TONIGHT. THE HRRR/NAM/GFS ALL PINPOINTING
THIS DISTURBANCE FOR HEAVY RAINFALL/NUMEROUS STORMS FROM 0Z-6Z,
WHICH COULD VERY WELL SURVIVE INTO KTMB/KMIA/KOPF TONIGHT.
THEREFORE, LEFT VCTS IN THROUGH PART OF THE EVENING, WITH THE
POTENTIAL FOR SOME MVFR/IFR IF GUIDANCE IS CORRECT. FARTHER NORTH
ALONG THE EAST COAST, VCSH WAS USED BUT AGAIN POSSIBLE THAT NUMEROUS
SHOWERS AND STORMS AFFECT THOSE TAF SITES TOO.
&&
.PREV DISCUSSION... /ISSUED 1105 AM EDT SAT SEP 13 2014/
UPDATE...
WHILE SHOWER AND THUNDERSTORM ACTIVITY HAS SUBSIDED ACROSS THE
REGION THIS MORNING...THE POTENTIAL FOR ACTIVE CONVECTION
CONTINUES. RECENT VISIBLE SATELLITE IMAGERY INDICATES ACTIVE
CONVECTION IN THE EASTERN GULF ASSOCIATED WITH THE AREA OF LOW
PRESSURE OFF THE SOUTHWEST FLORIDA COAST AND ADDITIONAL CONVECTION
IN THE CENTRAL BAHAMAS ISLANDS. THE 12Z SOUNDING INDICATED A PWAT
AROUND 1.9 INCHES AND INDICATED A SIGNIFICANT COOLING TREND IN THE
MID LEVELS AS WELL. GIVEN THE GENERAL CLEARING TREND OVER THE
PENINSULA THIS MORNING...DAY TIME HEATING IS EXPECTED TO DRIVE
CONVECTION THIS AFTERNOON AND EARLY EVENING WITH THE GREATEST
COVERAGE OF SHOWERS AND THUNDERSTORMS STILL EXPECTED IN THE
WESTERN INTERIOR AND WESTERN PORTIONS OF THE PENINSULA...INCLUDING
THE NAPLES METRO AREAS.
60
PREV DISCUSSION... /ISSUED 830 AM EDT SAT SEP 13 2014/
AVIATION...
RATHER DISORGANIZED UPPER LOW, WITH A FEW DISTURBANCES TRAILING
TO THE EAST, WILL BE THE IMPETUS FOR STORMS TODAY. LARGE MASS OF
MID LEVEL DRY AIR PER WATER VAPOR LOOP, MAY STAY NORTH OF THE
REGION TODAY, UNLIKE YESTERDAY. PERHAPS SOME OF THIS DRY AIR WILL
WRAP INTO THE CIRCULATION OF THE UPPER LOW, BUT THAT MAY NOT MEAN
MUCH SINCE THE LOW IS ALREADY OFF THE SW FL COAST. LAMP GUIDANCE
INDICATES THAT A SEA BREEZE WILL DEVELOP ALONG THE EAST COAST,
PERHAPS KEEPING MOST CONVECTION INLAND AND WEST COAST. THIS IS UP
AGAINST THE HRRR WHICH IS AGGRESSIVE PAINTING STORMS ALONG THE
BEACHES AND MOST TERMINALS BY MID AFTERNOON. THE TAFS CAN BE FINE
TUNED ONCE RAOB DATA ARRIVES, BUT WILL INSERT VCTS FOR NOW, AS
PREVIOUS DISCUSSION MENTIONED VCTS FOR ALL TAFS, BUT TAFS ONLY
CONTAINED VCSH. PERHAPS SOME OF THE SHOWERS OFFSHORE OF PBI ARRIVE
LATER THIS MORNING. PERSISTENCE OF CLOUD COVER ALONG THE EAST
COAST WILL ALSO GO A LONG WAY IN DETERMINING STORM EVOLUTION
TODAY. CONFIDENCE IS BELOW AVERAGE.
PREV DISCUSSION... /ISSUED 431 AM EDT SAT SEP 13 2014/
SHORT TERM...(TODAY-MONDAY)
RECENTLY ANIMATED WATER VAPOR LOOP SHOWED AN UPPER LOW CENTERED OVER
SOUTH FLORIDA SLOWLY TRACKING WESTWARD AND A RIDGE AXIS ORIENTED
FROM EAST TO WEST ACROSS THE NORTHERN GULF COAST STATES. PLENTY OF
DEEP LAYER MOISTURE EAST OF THIS UPPER LOW COMBINED WITH UPPER-LEVEL
DIVERGENCE WILL CONTINUE TO SUPPORT WIDESPREAD RAINFALL TODAY
ESPECIALLY ALONG THE SOUTHEAST COAST AND ACROSS THE ATLANTIC
WATERS THROUGH THE MORNING HOURS. THE LATEST HRRR MODEL RUN APPEARS
TO HAVE INITIALIZED WELL WITH THE CURRENT RADAR TRENDS AND GENERALLY
INDICATES THIS MORNING ACTIVITY CONTINUING ACROSS THE EASTERN
AREAS INCLUDING PALM BEACH, BROWARD AND MIAMI-DADE BEFORE SHIFTING
INLAND AND TOWARD THE GULF COAST THROUGH THE MID TO LATE
AFTERNOON/EARLY EVENING PERIOD. THIS SOLUTION MAKES SENSE WITH THE
UPPER LOW SHIFTING WESTWARD AND LIGHT TO MODERATE SOUTHEAST LOW-
LEVEL FLOW CONTINUING. THIS PATTERN WILL KEEP THE POTENTIAL FOR
LOCALIZED FLOODING UP THROUGH THIS EVENING...ESPECIALLY OVER THE
AREAS THAT ARE ALREADY SATURATED FROM EARLIER RAINFALL (AREAS HAVE
RECEIVED 2-4 INCHES WITH HIGHER AMOUNTS UP TO 7" JUST INLAND OF
BOCA RATON OVER THE PAST 24-36 HRS). MODEL SOUNDINGS SUPPORT THE
ACTIVITY TAPERING OFF OVER THE FAR SOUTHEASTERN AREAS OR TOWARD
MIAMI THROUGH THE MORNING AND AFTERNOON HOURS WITH MAINLY
SATURATED PROFILES ABOVE A SLIGHTLY DRIER LAYER FROM THE SURFACE
TO 700MB. AS A RESULT...MAXIMUM TEMPERATURES HAVE BEEN SLIGHTLY
UNDERCUT BY A FEW DEGREES COMPARED TO GUIDANCE...MAINLY DUE TO
PLENTY OF CLOUD COVERAGE ANTICIPATED. IF THIS COVERAGE BEGINS TO
BREAK THROUGH THE DAY...TEMPERATURES WILL NEED TO BE ADJUSTED
ACCORDINGLY. THE MOIST TREND WITH SOUTHEAST FLOW WILL PERSIST
THROUGH SUNDAY BEFORE SOME DRIER AIR MOVES IN FROM THE WEST AND
THE RIDGE BUILDS BACK ACROSS THE REGION INTO THE UPCOMING WEEK.
/85
LONG TERM (TUESDAY-FRIDAY)...
THE LATEST EXTENDED GUIDANCE REMAINS IN DECENT AGREEMENT ON THE
LARGE SCALE AND GENERALLY INDICATES FALLING UPPER HEIGHTS IN
RESPONSE TO A DEEPENING UPPER TROUGH ACROSS THE REGION. A FRONTAL
BOUNDARY IS PROJECTED TO SHIFT SOUTHWARD AND STALL NORTH OF THE AREA
THROUGH THE SECOND HALF OF THE WEEK. THE ECMWF SEEMS TO BE THE MORE
BULLISH SOLUTION AND SHOWS THE MOISTURE AXIS ASSOCIATED WITH THIS
BOUNDARY PROGRESSING FARTHER SOUTH THAN THE GFS/GFS ENSEMBLE MEAN
WITH SSW LOW-LEVEL FLOW SETTING UP OVER THE AREA BY THURSDAY. THE
COMBINATION OF THE FRONT AND FALLING UPPER HEIGHTS ALONG WITH SSW
LOW-LEVEL FLOW WOULD FAVOR MUCH OF THE RAINFALL SETTING UP OVER THE
EAST COAST/METRO AREAS BY THURSDAY.
/85
AVIATION...
A LARGE AREA OF SHOWERS AND THUNDERSTORMS OVER THE ATLANTIC WATERS
WERE DEVELOPING ON THE NORTHEAST SIDE OF THE MID/UPPER LEVEL
VORTICITY MOVING WEST ACROSS THE FLORIDA STRAITS. THESE
SHOWERS/STORMS WERE MOVING QUICKLY TO THE NORTHWEST TOWARDS THE
BROWARD AND MIAMI-DADE TAF SITES...AND THEY MAY MOVE OVER THE TAF
SITES THROUGH THE EARLY MORNING HOURS. BRIEF MVFR/IFR CONDITIONS AND
GUSTY WINDS UP TO 30 KNOTS ARE POSSIBLE. THE AREA OF LOW PRESSURE
OVER THE SOUTHEAST GULF AND THE UPPER LEVEL LOW WILL CONTINUE TO
MOVE WEST TODAY AND HAVE LESS OF AN INFLUENCE OVER THE REGION
THROUGHOUT THE DAY. THIS COMBINED WITH THE OVERNIGHT CONVECTION MAY
LIMIT SHOWER/STORM DEVELOPMENT FOR THE EAST COAST METRO AREAS DURING
THE DAY. HOWEVER...DEEP MOISTURE IN THE SOUTHEAST LOW LEVEL FLOW
WILL CONTINUE...SO KEPT VCTS IN FOR THE TAF SITES. AT KAPF...SHOWER
AND STORM DEVELOPMENT IS FORECAST TO BECOME MORE LIKELY AS THE DAY
PROGRESSES...AS THE INFLUENCE OF THE UPPER LOW INCREASES. LIGHT
WINDS WILL CONTINUE THROUGH THE OVERNIGHT HOURS OUTSIDE OF SHOWERS
AND STORMS...AND THEN BECOME SOUTHEAST AROUND 10 KNOTS DURING THE
DAY.
/84
MARINE...
AN UPPER LOW WILL KEEP THE RAIN CHANCES IN THE FORECAST ACROSS THE
MARINE AREAS THROUGH THE REMAINDER OF THE WEEKEND WITH LIGHT TO
MODERATE SOUTHEAST WINDS CONTINUING. WINDS AND SEAS WILL BE LOCALLY
HIGHER IN AND AROUND HEAVIER SHOWERS AND STORMS. HIGH PRESSURE WILL
BUILD BACK ACROSS THE REGION THROUGH THE FIRST HALF OF THE UPCOMING
WEEK WITH SOUTHEAST WINDS CONTINUING.
&&
.PRELIMINARY POINT TEMPS/POPS...
WEST PALM BEACH 76 87 76 87 / 30 50 30 50
FORT LAUDERDALE 77 87 79 88 / 40 60 20 50
MIAMI 77 87 78 88 / 40 60 20 50
NAPLES 75 89 76 89 / 30 60 20 50
&&
.MFL WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
AM...NONE.
GM...NONE.
&&
$$
SHORT TERM...60/BD
LONG TERM....85/AG
AVIATION...21/KM
AREA FORECAST DISCUSSION
NWS WAKEFIELD VA
436 PM EDT SAT SEP 13 2014
.SYNOPSIS...
A TROUGH OF LOW PRESSURE WILL MOVE OFF THE COAST THIS
EVENING...BUT A FRONTAL BOUNDARY WILL THEN LAY OFF THE SOUTHEAST
COAST TONIGHT THROUGH MONDAY. MEANWHILE...HIGH PRESSURE WILL BUILD
FROM THE OHIO VALLEY EAST NORTHEAST AND OFF THE NEW ENGLAND COAST
TONIGHT THROUGH MONDAY. ANOTHER TROUGH OF LOW PRESSURE WILL AFFECT
THE AREA MONDAY EVENING INTO TUESDAY.
&&
.NEAR TERM /UNTIL 6 AM SUNDAY MORNING/...
AREA OF SCTD SHOWERS (ISLTD THUNDER SE) WILL MOVE THRU CNTRL/ERN
CNTIES AND OFF THE CST THIS EVENG...AS A TROF OF LO PRES PUSHES
THRU AND OFFSHR. THEN...BECMG MSTLY CLEAR N TO PRTLY/MSTLY CLOUDY
S TNGT. LOWS RANGING FM THE MID 50S EXTRM N TO THE MID 60S SE.
&&
.SHORT TERM /6 AM SUNDAY MORNING THROUGH TUESDAY/...
SUN THRU MON...A FRONTAL BOUNDARY WILL LAY OFF THE SE CST...WHILE
HI PRES BLDS FM THE OH VLY ENE AND OFF THE NEW ENGLAND CST. THIS
WILL RESULT IN MAINLY DRY WX ACRS THE REGION WITH ONLY SLGT CHCS
FOR PCPN OVR THE EXTRM S. HI TEMPS ON SUN WILL BE IN THE LWR TO
MID 70S...WITH SKY COVER RANGING FM MOSTLY SNY EXTRM N TO MOSTLY
CLOUDY EXTRM S. ABT THE SAME SKY CONDITION SUN NGT WITH LOWS
RANGING THRU THE 50S INTO THE LWR 60S. PARTLY SNY TO MOSTLY CLOUDY
ON MON. WARMER AND BECMG A LITTLE MORE HUMID WITH HIGHS IN THE UPR
70S TO LWR 80S.
WILL THEN HAVE CHC POPS (30-40%) FOR THE ENTIRE REGION MON EVENG
INTO EARLY TUE MORNG...AS ANOTHER TROF OF LO PRES APPROACHES AND
SWINGS THRU. THAT TROF WILL MOVE OUT TO SEA TUE AFTN...WITH HI
PRES BLDNG TWD THE AREA FM THE OH VLY. LOWS MON NGT IN THE 60S.
HIGHS ON TUE RANGING FM THE MID 70S TO NEAR 80.
&&
.LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/...
MODELS AGREE THAT THE COLD FRONT IS WELL OFFSHORE WITH HIGH PRESSURE
BUILDING INTO THE AREA FROM THE NW TO START MEDIUM RANGE PERIOD. DRY
AND COOLER THRU WED NIGHT. LOWS IN THE 50S XCPT 60-65 BEACHES. HIGH
WED 70-75.
PATTERN FOR THE REST OF THE PERIOD WILL FEATURE A LARGE AREA OF HIGH
PRES OVER EASTERN CANADA THAT EXTENDS SOUTH ACROSS THE MID ATLNTC
RGN WITH THE OLD FRONTAL BOUNDARY STALLED ACROSS FLA AND IVOF GULF
STREAM. LOW PRESSURE PROGGED TO MOVE EAST ALONG THIS BNDRY THU AND
FRI. WHAT THIS SCENARIO SUGGESTS IS FOR AN EXTENDED AND INCREASINGLY
MOIST NE FLOW ACROSS THE RGN. TIGHTENING PRES GRAD WILL LEAD TO
BREEZY TO WINDY CNDTNS AT TIMES ALONG THE COAST. TIMING OF PCPN
RATHER PROBLEMATIC THIS FAR OUT BUT WILL CONFINE LOW CHC POPS TO
SERN COASTAL AREAS FOR NOW. PT SUNNY NORTH & WEST TO MSTLY CLDY TO
CLOUDY SKIES SOUTH & EAST. COOL WITH HIGHS U60S-M70S. LOWS IN THE
50S XCPT 60-65 CSTL AREAS.
&&
.AVIATION /20Z SATURDAY THROUGH THURSDAY/...
WEAK TROF WILL MOVE ACROSS THE AREA THIS AFTERNOON AND EVENING.
THIS IS GENERATING A FEW SHOWERS AS IT MOVES THROUGH THE VERY
MOIST AIR MASS OVER THE AREA. TIMING WHAT WE CAN SEE ON THE RADAR
AND WITH THE HRRR AND RUC ALL SHOW ABOUT A 4 HOUR WINDOW OF
SHOWERS. MAINLY FROM 18 TO 20Z WEST TO 20 TO 00Z EAST. CONDITIONS
WILL BE MVFR DURING THE SHOWERS. AFTER THIS TROF MOVES BY STILL NOT A LOT
OF FLOW ALOFT TO GET RID OF ALL THE MOISTURE. BUFKIT SOUNDINGS
KEEP SOME MID LEVEL MOISTURE AROUND THRU THE NIGHT. SO WILL RAISE
CIGS TO VFR TONIGHT. LOOKS LIKE CONTINUED DRYING ON SUNDAY AND
KEPT VFR CONDITIONS.
OUTLOOK...PCPN AND LOWER CONDITIONS MAY RETURN LATE MONDAY OR TUESDAY
WITH A RETURN TO DRY WEATHER ON WEDNESDAY. STILL UNCERTAINTY ABOUT
TIMING AND HOW FAR NORTH THE MOISTURE WILL GET IN OUR AREA.
&&
.MARINE...
WINDS WILL QUICKLY TURN TO THE NORTH BEHIND THE PASSAGE OF A TROF
THIS EVENING. MODELS STILL DEPICTING A DECENT CAA SURGE LATE TONIGHT
AND SUNDAY MORNING SO WILL KEEP CRNT SCA HEADLINES. ONLY CHANGE WAS
TO BEGING THE SCA HEADLINES WITH THIS ISSUANCE FOR THE CHES BAY
SINCE THE WINDS SHOULD INCREASE TO SCA LEVELS ARND MIDNIGHT. WILL
LET THE STARTING TIME FOR SCA`S ALONE FOR LATE TONIGHT AS THERE ARE
GNRLY FOR 5 FOOT SEAS (ALTHOUGH THERE CUD BE A FEW GUSTS TO 25 KTS
LATE TONIGHT).
SURGE QUICKLY DMNSHS BY SUNDAY AFTRN SO WILL LET THE SCA`S EXPIRE AT
ADVERTISED TIMES. NE FLOW SETS UP SUN NIGHT TINTO MON MORN AT SPEEDS
AOB 15 KTS. WINDS SHIFT INTO THE E-SE MONDAY AFTRN AND EVEN AHEAD OF
NEXT BNDRY.
NEXT COLD FRONTAL PASSAGE EXPECTED TUE MORNING WITH YET ANOTHER
MANGINAL CAA SURGE EXPECTED BEHIND IT. MODELS CONTINUE TO INDICATE
AN EXTENDED PERIOD OF NE (SCA) WINDS AND SEAS AOA 5 FT STARTING
MID WEEK AND PSBLY LASTING INTO NEXT WEEKEND.
&&
.AKQ WATCHES/WARNINGS/ADVISORIES...
MD...MODERATE RIP CURRENT RISK THROUGH SUNDAY EVENING FOR MDZ025.
NC...MODERATE RIP CURRENT RISK THROUGH SUNDAY EVENING FOR NCZ102.
VA...MODERATE RIP CURRENT RISK THROUGH SUNDAY EVENING FOR
VAZ098>100.
MARINE...SMALL CRAFT ADVISORY UNTIL 11 AM EDT SUNDAY FOR ANZ630>632-634-
638.
SMALL CRAFT ADVISORY FROM 6 AM TO 1 PM EDT SUNDAY FOR ANZ633.
SMALL CRAFT ADVISORY FROM 5 AM TO 11 AM EDT SUNDAY FOR ANZ652-
654-656.
SMALL CRAFT ADVISORY FROM 2 AM TO 11 AM EDT SUNDAY FOR ANZ650.
SMALL CRAFT ADVISORY FROM 5 AM TO 2 PM EDT SUNDAY FOR ANZ658.
&&
$$
SYNOPSIS...TMG
NEAR TERM...TMG
SHORT TERM...TMG
LONG TERM...MPR
AVIATION...JAB
MARINE...MPR
AREA FORECAST DISCUSSION
NWS WAKEFIELD VA
409 PM EDT SAT SEP 13 2014
.SYNOPSIS...
A TROUGH OF LOW PRESSURE WILL MOVE OFF THE COAST THIS
EVENING...BUT A FRONTAL BOUNDARY WILL THEN LAY OFF THE SOUTHEAST
COAST TONIGHT THROUGH MONDAY. MEANWHILE...HIGH PRESSURE WILL BUILD
FROM THE OHIO VALLEY EAST NORTHEAST AND OFF THE NEW ENGLAND COAST
TONIGHT THROUGH MONDAY. ANOTHER TROUGH OF LOW PRESSURE WILL AFFECT
THE AREA MONDAY EVENING INTO TUESDAY.
&&
.NEAR TERM /UNTIL 6 AM SUNDAY MORNING/...
AREA OF SCTD SHOWERS (ISLTD THUNDER SE) WILL MOVE THRU CNTRL/ERN
CNTIES AND OFF THE CST THIS EVENG...AS A TROF OF LO PRES PUSHES
THRU AND OFFSHR. THEN...BECMG MSTLY CLEAR N TO PRTLY/MSTLY CLOUDY
S TNGT. LOWS RANGING FM THE MID 50S EXTRM N TO THE MID 60S SE.
&&
.SHORT TERM /6 AM SUNDAY MORNING THROUGH TUESDAY/...
MAINLY DRY WEATHER IS EXPECTED SUNDAY THROUGH MONDAY WITH ONLY
SLGT CHANCES FOR PCPN IN THE FAR SOUTH. HIGH TEMPERATURES HOLD IN
THE 70S SUNDAY. DUE TO AN INCREASE OF SUNSHINE FROM EARLIER
FORECASTS...HAVE INCREASED TEMPERATURES TO NEAR 80 OVER MOST
INLAND SECTIONS ON MONDAY WITH READINGS HOLDING IN THE MID 70S ON
THE LOWER EASTERN SHORE.
&&
.LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/...
MODELS AGREE THAT THE COLD FRONT IS WELL OFFSHORE WITH HIGH PRESSURE
BUILDING INTO THE AREA FROM THE NW TO START MEDIUM RANGE PERIOD. DRY
AND COOLER THRU WED NIGHT. LOWS IN THE 50S XCPT 60-65 BEACHES. HIGH
WED 70-75.
PATTERN FOR THE REST OF THE PERIOD WILL FEATURE A LARGE AREA OF HIGH
PRES OVER EASTERN CANADA THAT EXTENDS SOUTH ACROSS THE MID ATLNTC
RGN WITH THE OLD FRONTAL BOUNDARY STALLED ACROSS FLA AND IVOF GULF
STREAM. LOW PRESSURE PROGGED TO MOVE EAST ALONG THIS BNDRY THU AND
FRI. WHAT THIS SCENARIO SUGGESTS IS FOR AN EXTENDED AND INCREASINGLY
MOIST NE FLOW ACROSS THE RGN. TIGHTENING PRES GRAD WILL LEAD TO
BREEZY TO WINDY CNDTNS AT TIMES ALONG THE COAST. TIMING OF PCPN
RATHER PROBLEMATIC THIS FAR OUT BUT WILL CONFINE LOW CHC POPS TO
SERN COASTAL AREAS FOR NOW. PT SUNNY NORTH & WEST TO MSTLY CLDY TO
CLOUDY SKIES SOUTH & EAST. COOL WITH HIGHS U60S-M70S. LOWS IN THE
50S XCPT 60-65 CSTL AREAS.
&&
.AVIATION /20Z SATURDAY THROUGH THURSDAY/...
WEAK TROF WILL MOVE ACROSS THE AREA THIS AFTERNOON AND EVENING.
THIS IS GENERATING A FEW SHOWERS AS IT MOVES THROUGH THE VERY
MOIST AIR MASS OVER THE AREA. TIMING WHAT WE CAN SEE ON THE RADAR
AND WITH THE HRRR AND RUC ALL SHOW ABOUT A 4 HOUR WINDOW OF
SHOWERS. MAINLY FROM 18 TO 20Z WEST TO 20 TO 00Z EAST. CONDITIONS
WILL BE MVFR DURING THE SHOWERS. AFTER THIS TROF MOVES BY STILL NOT A LOT
OF FLOW ALOFT TO GET RID OF ALL THE MOISTURE. BUFKIT SOUNDINGS
KEEP SOME MID LEVEL MOISTURE AROUND THRU THE NIGHT. SO WILL RAISE
CIGS TO VFR TONIGHT. LOOKS LIKE CONTINUED DRYING ON SUNDAY AND
KEPT VFR CONDITIONS.
OUTLOOK...PCPN AND LOWER CONDITIONS MAY RETURN LATE MONDAY OR TUESDAY
WITH A RETURN TO DRY WEATHER ON WEDNESDAY. STILL UNCERTAINTY ABOUT
TIMING AND HOW FAR NORTH THE MOISTURE WILL GET IN OUR AREA.
&&
.MARINE...
WINDS WILL QUICKLY TURN TO THE NORTH BEHIND THE PASSAGE OF A TROF
THIS EVENING. MODELS STILL DEPICTING A DECENT CAA SURGE LATE TONIGHT
AND SUNDAY MORNING SO WILL KEEP CRNT SCA HEADLINES. ONLY CHANGE WAS
TO BEGING THE SCA HEADLINES WITH THIS ISSUANCE FOR THE CHES BAY
SINCE THE WINDS SHOULD INCREASE TO SCA LEVELS ARND MIDNIGHT. WILL
LET THE STARTING TIME FOR SCA`S ALONE FOR LATE TONIGHT AS THERE ARE
GNRLY FOR 5 FOOT SEAS (ALTHOUGH THERE CUD BE A FEW GUSTS TO 25 KTS
LATE TONIGHT).
SURGE QUICKLY DMNSHS BY SUNDAY AFTRN SO WILL LET THE SCA`S EXPIRE AT
ADVERTISED TIMES. NE FLOW SETS UP SUN NIGHT TINTO MON MORN AT SPEEDS
AOB 15 KTS. WINDS SHIFT INTO THE E-SE MONDAY AFTRN AND EVEN AHEAD OF
NEXT BNDRY.
NEXT COLD FRONTAL PASSAGE EXPECTED TUE MORNING WITH YET ANOTHER
MANGINAL CAA SURGE EXPECTED BEHIND IT. MODELS CONTINUE TO INDICATE
AN EXTENDED PERIOD OF NE (SCA) WINDS AND SEAS AOA 5 FT STARTING
MID WEEK AND PSBLY LASTING INTO NEXT WEEKEND.
&&
.AKQ WATCHES/WARNINGS/ADVISORIES...
MD...MODERATE RIP CURRENT RISK THROUGH SUNDAY EVENING FOR MDZ025.
NC...MODERATE RIP CURRENT RISK THROUGH SUNDAY EVENING FOR NCZ102.
VA...MODERATE RIP CURRENT RISK THROUGH SUNDAY EVENING FOR
VAZ098>100.
MARINE...SMALL CRAFT ADVISORY UNTIL 11 AM EDT SUNDAY FOR ANZ630>632-634-
638.
SMALL CRAFT ADVISORY FROM 6 AM TO 1 PM EDT SUNDAY FOR ANZ633.
SMALL CRAFT ADVISORY FROM 5 AM TO 11 AM EDT SUNDAY FOR ANZ652-
654-656.
SMALL CRAFT ADVISORY FROM 2 AM TO 11 AM EDT SUNDAY FOR ANZ650.
SMALL CRAFT ADVISORY FROM 5 AM TO 2 PM EDT SUNDAY FOR ANZ658.
&&
$$
SYNOPSIS...TMG
NEAR TERM...TMG
SHORT TERM...TMG
LONG TERM...MPR
AVIATION...JAB
MARINE...MPR
AREA FORECAST DISCUSSION
NWS WAKEFIELD VA
148 PM EDT SAT SEP 13 2014
.SYNOPSIS...
A FRONTAL BOUNDARY WILL REMAIN OVER THE CAROLINAS THROUGH EARLY NEXT
WEEK. A TROUGH OF LOW PRESSURE WILL MOVE FROM WEST TO EAST ACROSS
THE MID ATLANTIC STATES THIS AFTERNOON AND EARLY TONIGHT. HIGH
PRESSURE BUILDS INTO THE AREA FROM THE NORTHWEST SUNDAY AND
MONDAY. ANOTHER LOW PRESSURE SYSTEM WILL AFFECT THE AREA MONDAY
NIGHT AND TUESDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
AREA OF SCTD SHOWERS WAS MOVING INTO WRN/CNTRL CNTIES LATE THIS
MORNG...AND WILL SPREAD ACRS THE REGION FM W TO E THIS AFTN INTO
TNGT...AS A TROF OF LO PRES PUSHING ACRS THE AREA AND OFF THE CST.
WILL MAINTAIN LIKELY POPS (60-70%) EVERYWHERE THRU THIS
AFTN...EVEN THO RAINFALL AMTS WILL GENERALLY BE .25 INCH OR LESS
OVR MOST OF THE RGION. HIGHER AMTS POSSIBLE OVR NE NC LATER TODAY
INTO TNGT. INSTABILITY WILL BE MARGINAL IN THE SE...SO HAVE JUST
SLGT CHC OF TSTM. HI TEMPS RANGING FM THE LWR 70S EXTRM NW TO THE
LWR 80S EXTRM SE.
&&
.SHORT TERM /SUNDAY THROUGH MONDAY/...
MAINLY DRY WEATHER IS EXPECTED SUNDAY THROUGH MONDAY WITH ONLY
SLGT CHANCES FOR PCPN IN THE FAR SOUTH. HIGH TEMPERATURES HOLD IN
THE 70S SUNDAY. DUE TO AN INCREASE OF SUNSHINE FROM EARLIER
FORECASTS...HAVE INCREASED TEMPERATURES TO NEAR 80 OVER MOST
INLAND SECTIONS ON MONDAY WITH READINGS HOLDING IN THE MID 70S ON
THE LOWER EASTERN SHORE.
&&
.LONG TERM /MONDAY NIGHT THROUGH SATURDAY/...
CONTINUED TO FAVOR THE ECMWF SOLN DURING THIS PERIOD. LOW PRESSURE
AND ASSCTD COLD FRONT MOVE ACROSS THE AREA MON NIGHT AND TUE. THIS
RUN A BIT FASTER WITH FROPA (TUES MORNING) THEN SHIFTS OFFSHORE.
SOME INSTAB NOTED AHEAD OF BNDRY SO WILL KEEP CHC POPS THRU THE
PERIOD WITH THUNDER CHCS OVR SRN SCTNS. MILD AHEAD OF THE BNDRY
WITH LOWS MON NITE IN THE 60S. HIGHS TUE 75-80.
FRONTAL BNDRY STALLS ACROSS THE CAROLINAS AS CANADIAN HIGH PRESSURE
BUILDS INTO THE AREA FOR THE MID WEEK PRD. MOST OF THE SGNFCNT MSTR
GETS PUSHES JUST SOUTH OF THE FA...SO WILL INDCT A DRY PRD WED AND
WED NIGHT. COOLER WITH LOWS IN THE 50S XCPT 60S BEACH AREAS. HIGHS
WED 70-75.
GIVEN HIGHS PRS TO THE NORTH AND STALLED FRNTL BNDRY TO THE SOUTH...
XPCT THE PERSISTENT & INCREASINGLY MOIST NE FLOW TO KEEP CSTL
AREAS RTHR CLDY WITH PERIODIC SHWR CHCS ACROSS SERN CSTL AREAS.
OTW...HIGH PRS TO THE NORTH DOMINATES. HIGHS L-M70S. LOWS IN THE
50S XCPT 60S CSTL AREAS.
&&
.AVIATION /18Z SATURDAY THROUGH THURSDAY/...
WEAK TROF WILL MOVE ACROSS THE AREA THIS AFTERNOON AND EVENING.
THIS IS GENERATING A FEW SHOWERS AS IT MOVES THROUGH THE VERY
MOIST AIR MASS OVER THE AREA. TIMING WHAT WE CAN SEE ON THE RADAR
AND WITH THE HRRR AND RUC ALL SHOW ABOUT A 4 HOUR WINDOW OF
SHOWERS. MAINLY FROM 18 TO 20Z WEST TO 20 TO 00Z EAST. CONDITIONS
WILL BE MVFR DURING THE SHOWERS. AFTER THIS TROF MOVES BY STILL NOT A LOT
OF FLOW ALOFT TO GET RID OF ALL THE MOISTURE. BUFKIT SOUNDINGS
KEEP SOME MID LEVEL MOISTURE AROUND THRU THE NIGHT. SO WILL RAISE
CIGS TO VFR TONIGHT. LOOKS LIKE CONTINUED DRYING ON SUNDAY AND
KEPT VFR CONDITIONS.
OUTLOOK...PCPN AND LOWER CONDITIONS MAY RETURN LATE MONDAY OR TUESDAY
WITH A RETURN TO DRY WEATHER ON WEDNESDAY. STILL UNCERTAINTY ABOUT
TIMING AND HOW FAR NORTH THE MOISTURE WILL GET IN OUR AREA.
&&
.MARINE...
SFC HI PRES MOVES OFF TO THE NE OF THE WTRS THROUGH TDA. ONSHORE
WNDS (LIGHTER THAN PAST 24 HRS) THROUGH THE MRNG...BECOME BRIEFLY
SSW AHD OF APPROACHING LO PRES AND ASSOCIATED CDFNT FM THE W.
SUB-SCA CONDS XPCD THROUGH THIS EVE. THAT CDFNT CROSSES THE WTRS MID
EVE...A BIT OF A LULL IN SPEEDS AS WNDS BECOME NLY POST FROPA. AS
SFC HI PRES FM THE OH VLY BUILDS E TNGT...SPEEDS TO INCRS TO 15-20
KT OVR MOST OF THE WTRS AFT MDNGT...AND RESULT IN INCRS IN WAVES
(BAY)/SEAS (OCN) THROUGH SUN MRNG. WNDS TO BEGIN TO SUBSIDE
MIDDAY/AFTN SUN AND WAVES/SEAS WILL BE SLO TO LWR AS WELL (LASTLY
INVOF FAR SRN OCN WTRS). RAISING SCAS FOR BAY/OCN/SND...MNLY FM AFT
MDNGT TNGT THROUGH MRNG/EARLY AFTN SUN.
ANOTHOR LO PRES SYS AND ASSOCIATED CD CDFRNT PROGGED ACROSS THE AREA
MON NGT AND TUE. EXPECT W-SW FLOW AHEAD OF THIS SYS
SHIFTING BACK TO THE N AFT FROPA WITH YET ANOTHER CAA SURGE
LIKELY. DATA INDICATES THAT AN EXTENDED PERIOD OF NE WINDS AND
INCREASED SEAS APPEAR LIKELY LATE NEXT WEEK.
&&
.AKQ WATCHES/WARNINGS/ADVISORIES...
MD...MODERATE RIP CURRENT RISK UNTIL 8 PM EDT THIS EVENING FOR
MDZ025.
NC...MODERATE RIP CURRENT RISK UNTIL 8 PM EDT THIS EVENING FOR
NCZ102.
VA...MODERATE RIP CURRENT RISK UNTIL 8 PM EDT THIS EVENING FOR
VAZ098>100.
MARINE...SMALL CRAFT ADVISORY FROM MIDNIGHT TONIGHT TO 11 AM EDT SUNDAY
FOR ANZ630>632-634-638.
SMALL CRAFT ADVISORY FROM 6 AM TO 1 PM EDT SUNDAY FOR ANZ633.
SMALL CRAFT ADVISORY FROM 5 AM TO 11 AM EDT SUNDAY FOR ANZ652-
654-656.
SMALL CRAFT ADVISORY FROM 2 AM TO 11 AM EDT SUNDAY FOR ANZ650.
SMALL CRAFT ADVISORY FROM 5 AM TO 2 PM EDT SUNDAY FOR ANZ658.
&&
$$
SYNOPSIS...LSA
NEAR TERM...TMG/LSA
SHORT TERM...LSA/JAB
LONG TERM...MPR
AVIATION...LSA
MARINE...ALB
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
410 PM EDT SAT SEP 13 2014
.SHORT TERM...(THIS EVENING THROUGH SUNDAY)
ISSUED AT 409 PM EDT SAT SEP 13 2014
WATER VAPOR IMAGERY AND RUC ANALYSIS SHOW THE VIGOROUS SHORTWAVE
THAT PRODUCED PCPN OVER MUCH OF UPPER MI LAST NIGHT NOW MOVING THRU
SRN ONTARIO INTO QUEBEC. UPSTREAM...A PAIR OF SHORTWAVES ARE
NOTED...ONE OVER ND/SRN MANITOBA AND THE OTHER OVER SRN
SASKATCHEWAN. THESE WAVES WILL BRING THE NEXT PCPN CHC TO UPPER MI
ON SUNDAY. IN THE WAKE OF LAST NIGHTS SYSTEM...850MB TEMPS ARE
CURRENTLY -1 TO -2C OVER LAKE SUPERIOR. TYPICALLY AT THIS TIME OF
YEAR...THIS WOULD BE MORE THAN SUFFICIENT FOR LAKE EFFECT CLOUDS AND
PCPN. HOWEVER...WITH A LARGE PORTION OF LAKE SUPERIOR HAVING SFC
WATER TEMPS PROBABLY ONLY AROUND 7-9C...THERE WAS NOT MUCH IN THE
WAY OF LAKE EFFECT CLOUDS EARLIER TODAY. IN FACT...THE LAKE HAS
BEHAVED MOSTLY AS STABILIZING INFLUENCE. ONE BAND WITH A FEW
SPRINKLES DID STREAM INTO ERN MARQUETTE COUNTY BRIEFLY THIS MORNING
DUE TO LAND BREEZE CONVERGENCE AND WARMER WATER TO THE S AND E OF
THE KEWEENAW. THIS AFTN...DAYTIME HEATING/LOW-LEVEL CONVERGENCE AND
MOISTURE FROM THE LAKE RESULTED IN ADDITIONAL SPRINKLES DEVELOPING
IN ERN MARQUETTE COUNTY. THESE SPRINKLES ARE DRIFTING SE THRU DELTA
AND WRN ALGER COUNTIES. WHILE LAKE EFFECT CLOUDS WERE AT A MINIMUM
EARLIER TODAY...850MB THERMAL TROF COMBINED WITH ADDED MOISTURE FROM
THE LAKE RESULTED IN WIDESPREAD CU/STRATOCU DEVELOPING OVER THE LAND
ONCE DAYTIME HEATING BEGAN.
TONIGHT...MAIN FCST CONCERN IS FROST POTENTIAL. WHILE CU/STRATOCU IS
STILL QUITE EXTENSIVE...THE DIURNAL NATURE OF THE CLOUD DEVELOPMENT
SUGGESTS THE CLOUDS WILL DISSIPATE THIS EVENING WITH THE LOSS OF
DAYTIME HEATING. MEANWHILE...LEAD SHORTWAVE TO THE W IS GENERATING A
FAIR AMOUNT OF HIGH CLOUDINESS WHICH WILL STREAM OVER THE FCST AREA
AS THE WAVE MOVES OVER THE UPPER LAKES. DISSIPATING STRATOCU THIS
EVENING BEING REPLACED BY HIGH CLOUDS WILL BE ONE FACTOR HELPING TO
KEEP TEMPS FROM CRASHING. OTHER FACTOR WILL BE DEPARTURE OF HIGH
PRES RIDGE CURRENTLY OVER THE AREA. AS PRES GRADIENT TIGHTENS BTWN
THE EXITING HIGH AND APPROACHING SFC TROF... THERE WILL BE SOME
INCREASE IN MIXING. THAT SAID...THE INITIAL DRY AIR MASS
(PRECIPITABLE WATER 45-55PCT OF NORMAL) AND LIGHT WINDS OVER THE
AREA WILL STILL ALLOW TEMPS TO FALL INTO THE MID 30S AND TO EVEN THE
LOWER 30S IN TRADITIONAL COLD SPOTS. SO...FCST WILL SHOW PATCHY
FROST OVER MUCH OF THE INTERIOR. AT THIS POINT...NOT EXPECTING
COVERAGE TO BE LARGE ENOUGH TO WARRANT A FROST ADVY. EVENING SHIFT
WILL NEED TO MONITOR CLOUD TRENDS AND TEMPS TO RE-EXAMINE THE NEED
FOR HEADLINE ISSUANCE BY LATE EVENING.
ON SUN...SECOND SHORTWAVE WILL SWING ACROSS THE UPPER GREAT LAKES.
AS IN PREVIOUS DAYS...MODELS CONTINUE TO INDICATE BEST
MOISTURE/FORCING PASSING JUST N OF THE AREA...ALONG AND N OF
PROJECTED VORT TRACK. SEE NO REASON TO DEVIATE MUCH FROM PREVIOUS
FCST WITH MAINLY CHC POPS SPREADING INTO WRN UPPER MI IN THE MID TO
LATE MORNING AND THEN REACHING THE E MID TO LATE AFTN. EXPECT HIGH
TEMPS GENERALLY IN THE UPPER 50S TO LWR 60S.
.LONG TERM...(SUNDAY NIGHT THROUGH SATURDAY)
ISSUED AT 350 PM EDT SAT SEP 13 2014
SPLIT FLOW PATTERN ALOFT TO START THE LONG TERM PERIOD BUT NORTHERN
BRANCH IS BY FAR STRONGER AND MORE INFLUENTIAL ON THE WEATHER OVER
MUCH OF NORTH AMERICA. TROUGHING CENTERED OVER NUNAVUT CANADA TO THE
NORTH OF HUDSON BAY WILL KEEP A TROUGH/BELOW NORMAL TEMPS OVER MOST
OF CANADA AND INTO THE GREAT LAKES AND REST OF THE EASTERN CONUS
THIS WEEK. RIDGING OVER THE WESTERN CONUS AND WESTERN CANADA SHOULD
SLOWLY SLIDE EAST BY THE END OF THE WEEK AS DEEP TROUGH CURRENTLY
OVER ALASKA RE-ORIENTS OVER THE GULF OF ALASKA WHILE SLIGHTLY
OPENING UP. MAY SEE A WARM UP LATE THIS WEEK AND BEYOND AS
RIDGING...OR AT LEAST LESS TROUGHING...AFFECTS THE PLAINS AND GREAT
LAKES. PATTERN DOES NOT LOOK TO PROVIDE MUCH IN WAY OF RAIN THE NEXT
WEEK. PRIMARY CHANCES WOULD BE WITH COLD FRONT MOVING THROUGH ON
TUESDAY NIGHT AND AGAIN BY NEXT WEEKEND AS WARM AIR ADVECTION STARTS
TO SPREAD IN FROM THE WEST.
SUNDAY NIGHT INTO MONDAY...SHORTWAVE AND ASSOCIATED COLD FRONT MOVES
OUT OF EASTERN CWA AFTER MIDNIGHT ON SUNDAY NIGHT. WILL LINGER SLIGHT
CHANCE POPS OVER THE EAST AFTER MIDNIGHT. THERMAL TROUGH WITH LOWER
H7 TEMPS AND A POCKET OF H85-H7 RH ALONG WITH DAYTIME HEATING MAY
RESULT IN ISOLD SHRA VCNTY OF LAKE BREEZES OVER EASTERN CWA ON
MONDAY AFTN. DRYING AND SUBSIDENCE IN WAKE OF THE SUNDAY NIGHT
SHORTWAVE SHOULD LIMIT COVERAGE AND WILL ONLY KEEP SLIGHT CHANCES.
LI/S ARE A BIT BLO 0C BUT THINK THAT WITH FROPA WITHIN PREVIOUS 12
HR...THERE WILL ONLY BE ENOUGH INSTABILITY FOR SHRA SO DID NOT
MENTION ANY THUNDER.
SFC RIDGE SETTLES FROM THE NORTHERN PLAINS TO THE OHIO VALLEY BY
TUESDAY MORNING. COULD BE HIGH CLOUDS ON MONDAY NIGHT...BUT PWATS
ARE BLO 50 PCT OF NORMAL SO IT COULD BE CHILLY NIGHT WITH SOME FROST
POSSIBLE. WINDS LIGHT NEAR THE RIDGE AND THERE IS LIMITED ONSHORE
COMPONENT ANYWHERE IN CWA...SEEMS THAT ALL INTERIOR WOULD BE AT RISK
FOR THE COLD TEMPS/FROST. TUESDAY SHOULD BE DRY AS UPPER LAKES IS
BTWN THE RIDGE AND AN APPROACHING COLD FRONT. WSW WINDS AHEAD OF
FRONT AND H85 TEMPS UP TO 4-6C SHOULD RESULT IN TEMPS INTO THE 60S
WHICH IS AT LEAST CLOSER TO NORMAL. FRONT DROPS NORTH TO SOUTH OVER
THE AREA ON TUESDAY NIGHT OR WEDNESDAY MORNING. A BRIEF INTERLUDE OF
INCREASING H8-H6 MOISTURE AND WEAK LIFT JUST IN WAKE OF THE FRONT
MAY BE ENOUGH TO KICK OFF SOME SHOWERS TUESDAY NIGHT. COVERAGE OF
ANY SHOWERS WILL BE HELD BACK AS STRONGER FORCING FOR LIFT REMAINS
OVER NORTHERN ONTARIO CLOSER TO TRACK OF UPPER LEVEL JET DIGGING
INTO THE PERSISTENT TROUGH. INTO WEDNESDAY...COULD BE A LOT OF LOW
CLOUDS LINGERING BENEATH SUBSIDENCE ALOFT AS SUB H85 IT REMAINS COOL
AND MOIST WITH EASTERLY FLOW. ADDITIONAL MID CLOUDS MAY STREAM ACROSS
IN THE AFTN AS WELL. TEMPS WILL BE MUCH COOLER THAN THE DAY BEFORE
AND IT WILL ESPECIALLY FEEL THAT WAY WITH THE CLOUDS AND EAST WIND.
TEMPS IN THE LOW 50S NEAR LK SUPERIOR AND NEAR 60 OVER THE SCNTRL.
AS TROUGH ALOFT OVER EASTERN CANADA AND THE NORTHEAST CONUS SLOWLY
MOVES EAST AND RIDGE OVER WESTERN CONUS ALSO MOVES EAST...CONFLUENT
FLOW RESULTS IN SFC RIDGE MOVING FROM CNTRL CANADA ACROSS THE GREAT
LAKES AND EVENTUALLY TO THE EASTERN SEABOARD BY SATURDAY. DRY WEATHER
SHOULD HOLD OVER UPPER LAKES THROUGH THU NIGHT...WITH CHANCES
FOR RAIN INCREASING BY NEXT WEEKEND AS SHORTWAVE TROUGH MOVES TO THE
CNTRL PLAINS AND SFC FRONT SLIDES EASTWARD. LATEST GFS WHICH HAD
BEEN VERY AGRESSIVE IN PREVIOUS MODEL RUNS BRINGING QPF TO THE
UPPER GREAT LAKES BY FRIDAY NOW LOOKS SIMILAR TO THE SLOWER 00Z
ECMWF. ON THE FLIP SIDE...THE LATEST ECMWF IS MUCH MORE BULLISH
BRINGING QPF ACROSS ALL OF UPR MICHIGAN BY FRIDAY AFTN AS WHERE IT
HAD BEEN INSISTENT ON A RIDGE...IT HAS A STRONGER SHORTWAVE TROUGH.
MODEL CONSISTENCY IS LACKING AND WILL GO WITH A CONSENSUS OF ALL THE
MODELS WITH LOW CHANCES FOR SHRA/TSRA BEGINNING ON FRIDAY AND
LASTING INTO NEXT WEEKEND. GENERALLY...TEMPS WILL RUN BELOW NORMAL
THE UPCOMING WEEK...THOUGH IT DOES APPEAR THAT IN ADDITION TO THE
WARMER TEMPS ON TUESDAY AHEAD OF A COLD FRONT...READINGS ON FRIDAY
AND SATURDAY MAY TRY TO PUSH TO AROUND NORMAL. WILL ALL DEPEND ON
EXTENT OF CLOUDS AND SHRA/TSRA. COUPLE OF CHILLY NIGHTS POSSIBLE
WEDNESDAY NIGHT AND THURSDAY NIGHT AS THE HIGH IS IN THE VCNTY AND
PWATS ARE WELL BLO 50 PCT OF NORMAL. IF SKIES ARE MAINLY CLEAR
EITHER NIGHT...TEMPS COULD BE AROUND FREEZING AND THERE WOULD BE
FROST. ATTM...BEST CHANCE FOR IDEAL RADIATIONAL COOLING CONDITIONS
WOULD BE ON WEDNESDAY NIGHT.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON)
ISSUED AT 137 PM EDT SAT SEP 13 2014
UNDER RELATIVELY DRY LOW LEVELS...VFR CONDITIONS WILL PREVAIL THRU
THE FCST PERIOD AT KIWD/KCMX/KSAW. THERE ARE A COUPLE OF MINOR
CONCERNS. A FEW -SHRA/SPRINKLES THAT HAVE POPPED UP IN THE KSAW
VCNTY SHOULD LINGER FOR THE NEXT COUPLE OF HRS. ON SUN...AN
APPROACHING LOW PRES TROF SHOULD BRING SCT -SHRA INTO NW UPPER MI BY
AFTN. HAVE INCLUDED A VCSH MENTION AT KCMX...BUT DO NOT EXPECT
CONDITION TO FALL BLO VFR.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 409 PM EDT SAT SEP 13 2014
APPROACHING LOW PRES TROF WILL RESULT IN INCREASING S TO SW WINDS
TONIGHT INTO SUN. WHILE LOWER OBS PLATFORMS SHOULDN`T SEE WINDS
GREATER THAN THE 10-20KT RANGE...HIGH OBS PLATFORMS WILL PROBABLY
SEE GUSTS TO AROUND 25KT. WINDS SHOULD FALL BACK TO MOSTLY 10-20KT
SUN NIGHT THRU MON. THERE MAY BE SOMEWHAT HIGHER WINDS AGAIN LATE
MON NIGHT THRU EARLY WED AHEAD OF AND BEHIND A COLD FRONT THAT WILL
DROP S ACROSS LAKE SUPERIOR TUE. LIGHTER WINDS WILL THEN BE THE RULE
LATER WED THRU THU HAS HIGH PRES MOVE SE ACROSS NRN ONTARIO TOWARD
THE LOWER LAKES.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...ROLFSON
LONG TERM...JLA
AVIATION...ROLFSON
MARINE...ROLFSON
AREA FORECAST DISCUSSION
NWS BISMARCK ND
338 PM CDT SAT SEP 13 2014
.SHORT TERM...(THIS EVENING THROUGH SUNDAY)
ISSUED AT 329 PM CDT SAT SEP 13 2014
COLD FRONT MOVING THROUGH THE REGION WILL GENERATE WIDELY
SCATTERED SHOWERS ACROSS NORTHERN NORTH DAKOTA THIS AFTERNOON AND
EARLY THIS EVENING. GENERALLY FOLLOWED THE HRRR IN AREA AND TIMING
OF THE SHOWERS. SHOWERS WILL END BEFORE MIDNIGHT. SKIES WILL CLEAR
WITH OVERNIGHT LOWS IN THE LOWER TO MIDDLE 30S WEST. ISSUED A
FROST ADVISORY ACROSS THE WEST...GENERALLY WEST OF THE MISSOURI
RIVER AND WEST OF MINOT. SURFACE HIGH PRESSURE WILL COVER THE
REGION SUNDAY AND ANOTHER ROUND OF PATCH FROST IS POSSIBLE SUNDAY
NIGHT.
.LONG TERM...(SUNDAY NIGHT THROUGH SATURDAY)
ISSUED AT 329 PM CDT SAT SEP 13 2014
THE EXTENDED PERIOD WILL REMAIN LARGELY DRY THROUGH THURSDAY AS A
LARGE UPPER LOW ACROSS EASTERN CANADA SLOWLY MOVES EAST. AS THIS
HAPPENS BROAD RIDGING WILL DEVELOP OVER THE CENTRAL AND NORTHERN
PLAINS. THIS WILL ALLOW A SLOW WARMING TREND THROUGH THE MIDDLE TO
AND OF NEXT WEEK. BY NEXT WEEKEND A COLD FRONT WILL MOVE THROUGH
BRINGING SCATTERED THUNDERSTORMS TO THE REGION THURSDAY NIGHT INTO
FRIDAY NIGHT.
FOR TEMPERATURES...SUNDAY NIGHT COULD SEE SOME SCATTERED FROST
BEFORE THE WARMUP BEGINS. OTHER THAN THAT...MORNING LOWS WILL B IN
THE 40S TO MIDDLE 50S WITH HIGHS IN THE 60S MONDAY AND THE 70S TO
AROUND 80 TUESDAY THROUGH SATURDAY.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON)
ISSUED AT 329 PM CDT SAT SEP 13 2014
COLD FRONT PROGRESSING THROUGH THE REGION. WHILE VFR CONDITIONS
ARE FORECAST THROUGH THE PERIOD...CLOUDS AS LOW AS 3 THOUSAND AGL
EXPECTED KDIK-KISN-KMOT AS THE COOLER AIR MOVES IN. SCATTERED
SHOWERS EXPECTED ACROSS THE NORTH UNTIL 03Z.BUT TOO WIDELY
SCATTERED TO INCLUDE IN THE TAF AT THIS TIME.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
FROST ADVISORY FROM 3 AM CDT /2 AM MDT/ TO 9 AM CDT /8 AM MDT/
SUNDAY FOR NDZ001-002-009-010-017>021-031>034-040>045.
&&
$$
SHORT TERM...WAA
LONG TERM...WAA
AVIATION...WAA
AREA FORECAST DISCUSSION
NWS GRAND FORKS ND
109 PM CDT SAT SEP 13 2014
.UPDATE...
ISSUED AT 101 PM CDT SAT SEP 13 2014
NO CHANGES NEEDED. FRONT TO REACH DVL 21Z OR SO WITH PSBL SHOWER
THEN A BIT BETTER CHC INTO THE NRN-CNTRL RRV 01-02Z.
UPDATE ISSUED AT 1017 AM CDT SAT SEP 13 2014
FCST GOING AS PLANNED...HIGH AND MID LEVEL CLOUDS OVER THE FCST
AREA IN AREA OF 850 MB WARM ADVECTION. 925 MB WINDS IN THE 25-30
KT RANGE 15-21Z WILL START TO GET TO THE SURFACE AS TEMPS WARM.
MAIN SFC LOW WEST OF BRANDON MANITOBA...MOVING EAST. RAIN SHOWERS
MOSTLY ASSOC WITH UPPER LOW JUST NORTH OF REGINA SK AND MODELS
CONTINUE TO KEEP MOST OF THE PRECIP WITH THIS EVENT JUST NORTH OF
THE BORDER TONIGHT THEN OVER LAKE OF THE WOODS REGION AND ONTARIO
SUNDAY. WILL CONTINUE WITH LOWER POPS SOUTH OF LOW WITH HRRR
SHOWING SOME SHOWERS LATER AFTN-EVE MOVING INTO NE ND/NRN RRV.
&&
.SHORT TERM...(TODAY THROUGH SUNDAY)
ISSUED AT 338 AM CDT SAT SEP 13 2014
NO CHANGE IN THE CURRENT FROST ADVISORY...ALTHOUGH A FEW LOCATIONS
OVER THE FAR EASTERN CWFA ARE IN THE MID 20S AT 08Z. WITH CIRRUS
INCREASING AND RETURN FLOW DEVELOPING DO NOT EXPECT TEMPERATURES
TO FALL MORE THAN 1 OR 2 DEGREES IN THE KVWU...KBJI...KBDO AND
KADC AREAS.
TODAY WILL BE A TRANSITION DAY. AS THE UNSEASONALLY COLD HIGH
MOVES SOUTH...LOW PRESSURE INTENSIFIES OVER SASKATCHEWAN SOUTH
WINDS WILL INCREASE BY MID DAY. THE MODELS INITIALIZED WELL AND
WILL FOLLOW THE HIGHER RESOLUTION HRRR AND NAM12 TODAY...BLENDING
THE NAM/GFS FOR TONIGHT INTO SUNDAY MORNING. TIMING OF WARM
ADVECTION PRECIPITATION AHEAD OF WELL DEFINED UPPER WAVE OVER
FAR NORTH-CENTRAL MONTANA SIMILAR TO PREVIOUS FORECAST REACHING THE
DEVILS LAKE BASIN AROUND 18Z AND SPREADING EAST. NAM/GFS HAVE
SMALL AREA OF 0C SHOWALTERS AND SOME ML CAPE BUT WILL NOT MENTION
TSRA ATTM. WITH WELL MIXED LAYER TO AROUND 800 MB...35 KTS AT 850
IN THE NAM AND NEAR 30 KTS IN THE GFS TRANSLATE TO GUSTS CLOSE TO
30 KTS POSSIBLE. MOS HAS 27 KTS AND WILL FOLLOW THAT FOR THE 18Z -
00Z PERIOD.
SECOND STRONGER SHORTWAVE...DROPPING ALONG THE ALBERTA/SASKATCHEWAN
BORDER IS FORECAST TO BE NEAR KDVL AT 06Z TONIGHT. SURFACE LOW
SLOWS AND WRAP AROUND SHRA SPREADING OVER THE EAST HALF OF THE
CWFA INTO SUNDAY MORNING.
THE COLUMN COOLS AND DRIES MOST AREAS SUNDAY...WITH LINGERING SHRA
OVER THE NORTHEAST PORTION OF THE CWFA...WITH STRONGER MID-UPPER
CAA ALONG SHEAR AXIS AND ENTRANCE REGION OF UPPER JET. THIS
QUICKLY MOVES OUT WITH PRECIPITATION ENDING BY 00Z MONDAY.
.LONG TERM...(SUNDAY NIGHT THROUGH FRIDAY)
ISSUED AT 338 AM CDT SAT SEP 13 2014
WINDS DIMINISH AND SKIES CLEAR AS HIGH PRESSURE MOVES ACROSS THE
CWFA. LOWS WILL FALL BACK INTO THE LOW TO MID 30S...BUT EXPECT
SUFFICIENT MIXING AT THIS TIME TO KEEP FROST/FREEZE RISK MINIMAL
FOR MONDAY MORNING. LIGHT SOUTHWEST WINDS AND PLENTIFUL SUNSHINE WILL
ALLOW MODEST WARM-UP MONDAY TO NEAR MID SEPTEMBER NORMALS. RISING
HEIGHTS AND CONTINUED WESTERLY FLOW WILL MAKE FOR A MAINLY CLEAR
AND MILD MONDAY NIGHT.
TUESDAY TO FRIDAY...CONFLUENT NW FLOW ALOFT FOR MUCH OF THE WEEK
WITH A QUICK TRANSITIONING PERIOD THURSDAY INTO FRIDAY. AS A RESULT
DRY CONDITIONS EXPECTED WITH MODERATING TEMPS AS THICKNESSES
INCREASE WITH RIDGING OVER THE FA BY THURSDAY. BY THURSDAY PM OR
FRIDAY DEPENDING ON MODEL OF CHOICE...500MB SW FLOW AND 850MB LLJ
BRING INSTABILITY INTO FA FROM WEST TO EAST. WENT WITH A MOSTLY
SHRA AND ISO THUNDER FOR WX GRIDS AS SHOWALTERS DO BECOME NEGATIVE
AHEAD OF THE SFC TROUGH EXPECTED TO IMPACT THE NORTHERN PLAINS
TOWARDS THE END OF THE WEEK. TEMPERATURES ABOVE NORMAL THROUGH THE
WEEK CAN BE EXPECTED WITH SOME HUMIDITY POSSIBLE BY WEEKS END.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON)
ISSUED AT 101 PM CDT SAT SEP 13 2014
VFR CIGS WITH SOUTHERLY WINDS SWITCHING TO THE WEST THIS EVENING
AS A FRONT MOVES ACROSS THE NORTHERN TIER OF THE CONUS. WILL SEE
SOME SHRA MOVE ACROSS THE NORTHERN VALLEY AND INTO NW MN IN THE
EARLY AFTN...AND WILL MENTION AT GFK AND TVF. NOT AS CONFIDENT AT
BJI WHERE SHRA MAY PETER OUT BEFORE MAKING IT THAT FAR EAST...BUT
WILL HOLD MID LEVEL CIGS IN THROUGH THE 18Z PD AS WRAP AROUND
MOISTURE SHOULD IMPACT BJI THE LONGEST.
&&
.FGF WATCHES/WARNINGS/ADVISORIES...
ND...NONE.
MN...NONE.
&&
$$
UPDATE...RIDDLE
SHORT TERM...EWENS
LONG TERM...JK/EWENS
AVIATION...SPEICHER
AREA FORECAST DISCUSSION
NWS BISMARCK ND
1247 PM CDT SAT SEP 13 2014
.UPDATE...
ISSUED AT 1235 PM CDT SAT SEP 13 2014
COLD FRONT PROGRESSING THROUGH THE REGION EARLY THIS AFTERNOON. SO
FAR SHOWERS ARE ONLY VERY WIDELY SCATTERED ACROSS THE NORTH WITH
MORE SHOWERS UPSTREAM IN SASK. WILL MAINTAIN SLIGHT CHANCE
THROUGH THE AFTERNOON NORTH. ONLY UPDATE WILL BE FOR WINDS...RAISED A
BIT WEST TO 20 TO 30 MPH.
UPDATE ISSUED AT 845 AM CDT SAT SEP 13 2014
CANCELLED THE FROST ADVISORY. REFINED THE CLOUD COVER BASED ON
SATELLITE TRENDS AS HIGH CLOUDS ARE FADING A BIT CENTRAL. UPPED
THE WINDS A BIT AFTER THE FRONTAL PASSAGE.
UPDATE ISSUED AT 633 AM CDT SAT SEP 13 2014
LATEST SURFACE ANALYSIS SHOWS SURFACE CDFNT OVER WESTERN NORTH
DAKOTA WITH STRATOCU DECK DROPPING SOUTH FROM ALBERTA AND WESTERN
SASKATCHEWAN INTO NORTH CENTRAL MONTANA. LATEST 10 UTC RAP LOOKS
TO BE A LITTLE TOO QUICK IN BRINGING HIGHER 850 MB MOISTURE INTO
WESTERN NORTH DAKOTA...BUT BASED ON LATEST SATELLITE AND
OBSERVATIONS HAVE BUMPED UP SKY COVER ACROSS THE WEST LATER THIS
MORNING AND OVER THE NORTH AND CENTRAL THIS AFTERNOON. NO CHANGES
TO POPS AT THIS TIME...KEEPING SLIGHT CHANCE MAINLY NORTH OF THE
I94 CORRIDOR...WHICH IS IN AGREEMENT WITH LATEST RAP/HRRR
ITERATIONS. CURRENT TEMPERATURES REMAIN IN THE MID 30S ACROSS MOST
OF THE FROST ADVISORY AREA...THUS WILL KEEP IT GOING.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 308 AM CDT SAT SEP 13 2014
EARLY MORNING WATER VAPOR IMAGERY SHOWED AN UPPER WAVE MOVING
SOUTHEAST ACROSS SOUTHERN SASKATCHEWAN WHICH WAS PUSHING A COLD
FRONT TOWARDS THE STATE. THE UPPER WAVE IS EXPECTED TO MOVE
QUICKLY ACROSS THE NORTHERN PLAINS TODAY ALONG WITH THE COLD
FRONT. THE MAIN QUESTION WILL BE HOW FAR SOUTH TO BRING A CHANCE
OF RAIN SHOWERS TODAY AS THE WAVE / COLD FRONT PASS. THERE ARE A
WIDE VARIETY OF MODEL SOLUTIONS WITH DIFFERING PLACEMENT...BUT DUE
TO THE STRENGTH OF THE WAVE OPTED TO FAVOR THE MODELS WHICH BRING
THE RAIN CHANCES FARTHER SOUTH INTO NORTH DAKOTA. IN FACT...AM A
BIT CONCERNED WE MAY NOT HAVE TAKEN THE POPS FAR ENOUGH SOUTH IF
THE 4.0KM WRF NMM VERIFIES. A POTENTIAL LIMITING FACTOR COULD BE
DRY AIR IN THE LOW LEVELS...SO KEPT THE RAIN CHANCES GENERALLY
NORTH OF I-94.
THE NEXT CONCERN SURROUNDS THE FROST ADVISORY WHICH IS IN PLACE
ACROSS ROUGHLY THE SOUTHERN HALF OF THE FORECAST AREA THIS
MORNING. PASSING HIGH CLOUDS AHEAD OF THE UPPER WAVE HAVE
HELPED TEMPERATURES RISE A FEW DEGREES OVERNIGHT IN SOME
LOCATIONS...BUT READINGS IN THE ADVISORY AREA REMAIN IN THE 30S
TO LOWER 40S. THE HIGH CLOUDS ARE RATHER THIN ON THEIR SOUTHERN
EDGE...AND WITH GFS LAMP GUIDANCE STILL SUPPORTING FALLING
TEMPERATURES AT MOST LOCATIONS...WILL KEEP THE ADVISORY IN PLACE.
.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 308 AM CDT SAT SEP 13 2014
THE LONG TERM PERIOD BEGINNING SUNDAY LOOKS RATHER TRANQUIL THROUGH
MID WEEK. PATCHY MORNING FROST CAN NOT BE RULED OUT EARLY SUNDAY AND
MONDAY MORNINGS WITH SURFACE HIGH PRESSURE OVER THE AREA AND A
NORTHWEST UPPER FLOW KEEPING SEASONABLY COOL AIR OVER THE NORTHERN
PLAINS. OTHERWISE IT LOOKS DRY WITH A WARMING TREND THROUGH MIDWEEK.
MORNING LOWS IN THE MID 30S TO LOWER 40S...AND DAYTIME HIGHS IN
THE UPPER 50S AND 60S SUNDAY AND MONDAY...WILL WARM TO THE MID 40S
TO MID 50S FOR LOWS...AND 70S FOR HIGHS BY MID TO LATE WEEK.
A PROGRESSIVE UPPER LEVEL TROUGH MOVING ONTO THE WESTERN U.S. COAST
ON THURSDAY WILL APPROACH THE NORTHERN PLAINS BY LATE FRIDAY.
THERE ARE DIFFERENCES IN THE HANDLING OF THIS WAVE BETWEEN THE GFS
AND ECMWF MODELS BUT BOTH BRING INCREASING MOISTURE AND A SMALL
CHANCE OF SHOWERS AND ISOLATED THUNDER LATE THURSDAY INTO EARLY
FRIDAY...WITH THE BEST CHANCE OF SHOWERS AND THUNDERSTORMS FRIDAY
AND FRIDAY NIGHT AND POSSIBLY LINGERING IN THE EAST EARLY
SATURDAY.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON)
ISSUED AT 1235 PM CDT SAT SEP 13 2014
COLD FRONT PROGRESSING THROUGH THE REGION. WHILE VFR CONDITIONS
ARE FORECAST THROUGH THE PERIOD...CLOUDS WILL LOWER TO 3 TO 5
THOUSAND AGL AS THE COOLER AIR MOVES IN FROM. SCATTERED SHOWERS
EXPECTED ACROSS THE NORTH UNTIL 00Z. TO WIDELY SCATTERED TO
INCLUDE IN THE TAF AT THIS TIME.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...WAA
SHORT TERM...CK
LONG TERM...TWH
AVIATION...WAA
AREA FORECAST DISCUSSION
NWS NORMAN OK
1237 PM CDT SAT SEP 13 2014
.DISCUSSION...
AVIATION DISCUSSION FOR THE 18Z TAFS IS BELOW.
&&
.AVIATION...
GENERALLY HAVE MODERATE TO HIGH CONFIDENCE IN THE TAFS
THROUGH 06Z...THEN DECREASING CONFIDENCE AFTERWARDS.
THINK ALL SITES WILL BE VFR BY 20Z WITH KOKC...KOUN...
AND KSPS AS THE LAST SITES TO HAVE MVFR CEILINGS.
REDEVELOPMENT OF VFR/MVFR CEILINGS 1500-5000 FT AGL
WILL LIKELY OCCUR AFTER 06Z...MAINLY SOUTHWEST OF KGAG-
KOKC-KMLC. HEIGHT OF THESE CEILINGS REMAINS MOST UNCERTAIN.
WINDS WILL GENERALLY SHIFT TO THE SOUTHEAST AT ALL SITES
BY 01Z.
MBS
&&
.PREV DISCUSSION... /ISSUED 1037 AM CDT SAT SEP 13 2014/
DISCUSSION...
PERSISTENT CLOUD COVER WILL MAINTAIN RELATIVELY COOL WEATHER INTO
THE AFTERNOON OVER MOST OF OKLAHOMA AND NORTH TEXAS. CURRENT
SATELLITE TRENDS APPEAR TO SUPPORT THE HRRR MODEL FORECAST OF
CLOUD BREAKUP THIS AFTERNOON...EARLIER IN PARTS OF NORTHERN
OKLAHOMA...WHERE THERE ARE ALREADY LARGE HOLES IN THE CLOUD COVER.
THE FORECAST WAS UPDATED EARLIER THIS MORNING TO ACCOUNT FOR THE
LATEST TRENDS AND EXPECTATIONS.
PREV DISCUSSION... /ISSUED 638 AM CDT SAT SEP 13 2014/
AVIATION...
13/12Z TAFS...MVFR CIGS WILL BE SEEN AT MOST TERMINALS THROUGH
ABOUT 15-17Z...WITH VFR EXPECTED THEREAFTER. NORTHERLY WINDS WILL
BECOME SOUTHEAST LATE TODAY AND INCREASE IN SPEED AFTER THIS
FORECAST PERIOD. LOW CLOUDS WILL BEGIN TO INCREASE TOWARD END OF
FORECAST PERIOD BUT WILL LEAVE FCST VFR FOR NOW.
PREV DISCUSSION... /ISSUED 410 AM CDT SAT SEP 13 2014/
DISCUSSION...
CLEARING...AT LEAST PARTIALLY...EXPECTED THE REGION TODAY. THE
GREATEST AMOUNT OF CLEARING EXPECTED OVER THE NORTH-CENTRAL
PORTIONS OF OKLAHOMA. SOUTHERN OKLAHOMA AND WESTERN NORTH TEXAS
MAY ACTUALLY SEE MORE CLOUDS THAN SUN TODAY. NO PRECIPITATION
EXPECTED TODAY OR TONIGHT.
RETURN TO SOUTHERLY FLOW TONIGHT AND SUNDAY WILL ALLOW MOISTURE
TO WORK ITS WAY BACK OVER REGION AND ALLOW CLOUDS TO FILL BACK IN
ON SUNDAY. RAIN CHANCES RETURN TO FORECAST SUNDAY NIGHT AS NEXT
UPPER LEVEL TROUGH AND ASSOCIATED COLD FRONT MOVE OVER SOUTHERN
PLAINS. MOST OF THE PRECIP EXPECTED NEAR THE FRONT AS IT
PROGRESSES SLOWLY SOUTH OVER OKLAHOMA TO THE RED RIVER VALLEY
MONDAY AFTERNOON AND MONDAY NIGHT. FRONT LIFTS BACK NORTH TUESDAY
INTO WEDNESDAY...AND WITH DEVELOPMENT OF NWLY FLOW...WILL BE A
FOCUS FOR SHOWERS AND STORMS WEDNESDAY INTO THURSDAY MAINLY OVER
THE EASTERN HALF OF OKLAHOMA. CONFIDENCE NOT QUITE AS HIGH SO POPS
WILL REMAIN ON THE LOW SIDE OF GUIDANCE. FAIR AMOUNT OF DISPARITY
IN THE MEDIUM RANGE MODELS FOR FRIDAY AND NEXT WEEKEND...WITH ECM
CURRENTLY SHOWING PROLONGED PERIOD OF RAIN AND GFS A MORE
PROGRESSIVE AND DRY PATTERN. TRENDS WILL NEED TO BE MONITORED
BEFORE POPS ARE INTRODUCED AT END OF FORECAST PERIOD.
&&
.PRELIMINARY POINT TEMPS/POPS...
OKLAHOMA CITY OK 66 57 80 66 / 0 0 10 20
HOBART OK 70 55 80 65 / 0 0 10 20
WICHITA FALLS TX 67 59 81 68 / 10 0 10 10
GAGE OK 71 53 82 63 / 0 0 10 10
PONCA CITY OK 67 53 79 65 / 0 0 10 20
DURANT OK 68 60 78 66 / 10 0 10 10
&&
.OUN WATCHES/WARNINGS/ADVISORIES...
OK...NONE.
TX...NONE.
&&
$$
23/17/17