Forecast Discussions mentioning any of
"HRRR" "RAP" "RR" "RUC13" "RUC" received at GSD on 04/16/15
AREA FORECAST DISCUSSION
NWS PHOENIX AZ
152 PM MST TUE APR 14 2015
.SYNOPSIS...A DRY COLD FRONT WILL PUSH SOUTHWARD THROUGH SOUTHEAST
CALIFORNIA AND ARIZONA TONIGHT AND WEDNESDAY. THIS WILL LEAD TO VERY
WINDY CONDITIONS OVER SOUTHEAST CALIFORNIA AND WESTERN ARIZONA. WINDS
WILL NOT BE QUITE AS STRONG OVER SOUTH-CENTRAL ARIZONA. THE FRONTAL
PASSAGE WILL ALSO LEAD TO MUCH COOLER TEMPERATURES...DIPPING BELOW
THE NORMAL BY THURSDAY. EXPECT A WARMING TREND FRIDAY THROUGH SUNDAY
WITH LITTLE CHANGE MONDAY.
&&
.DISCUSSION...WELL-DEFINED TROUGH ACROSS THE GREAT BASIN CONTINUES TO
TRANSLATE EASTWARD TODAY. STRONG WINDS HAVE ALREADY BEEN A MAJOR
IMPACT WITH THIS SYSTEM...PARTICULARLY IN THE SALT LAKE CITY AREA.
THIS PORTENDS A WINDY DAY TOMORROW ACROSS THE DESERT SOUTHWEST. UNTIL
THEN...PRE-FRONTAL REGIME WILL CONTINUE WITH WELL ABOVE NORMAL
TEMPERATURES.
RESIDUAL MOISTURE BELOW 600 MB IS APPARENT ACROSS SE AZ IN THE WAKE
OF THE TROUGH ACROSS NM WHILE MODEL DEPICTIONS OF THIS MOISTURE HAVE
VARIED CONSIDERABLY. EARLIER RUNS OF THE HRRR HAD SUGGESTED THE
POTENTIAL FOR CONVECTION ACROSS CENTRAL ARIZONA BUT THE LATEST RUNS
HAVE CORRECTLY TRENDED EASTWARD THIS AFTERNOON. LATEST SATELLITE
SHOWS CU DEVELOPING ACROSS EASTERN PIMA COUNTY AND POPS WERE LOWERED
ACROSS PINAL COUNTY FOR THIS AFTERNOON. FOCUS FOR THIS AFTERNOON REMAINS
ACROSS THE HIGHER ELEVATIONS OF SOUTHERN AND EASTERN AZ...WHERE
THUNDERSTORMS HAVE DEVELOPED ACROSS THE WHITE MOUNTAINS.
HOWEVER...STRONGEST FORCING FOR ASCENT IS STRONGER OFF TO THE WEST
CLOSER TO THE APPROACHING TROUGH AND ANY ACTIVITY THAT DOES DEVELOP
WILL ONLY BE ISOLATED IN COVERAGE. OTHERWISE...EXPECT MAINLY CLEAR
SKIES OVERNIGHT WITH A CONTINUATION OF THE ABOVE NORMAL TEMPERATURES.
&&
.PREVIOUS DISCUSSION... TONIGHT THROUGH THURSDAY...THE BRUNT OF THE
AFOREMENTIONED PACIFIC LOW PRESSURE SYSTEM WILL INITIALLY AFFECT
AREAS WELL NORTH OF OUR FORECAST AREA. HOWEVER...THERE WILL BE A DRY
COLD FRONT THAT PUSHES THROUGH SOUTHEAST CALIFORNIA AND ARIZONA
BEGINNING TONIGHT AND CONTINUING WEDNESDAY. VERY STRONG NORTHERLY
WINDS IN THE LOWER LEVELS WILL BE ASSOCIATED WITH THE FRONTAL
PASSAGE...MOST NOTABLY FOR WESTERN PORTIONS OF OUR FORECAST AREA IN
SOUTHEAST CALIFORNIA AND SOUTHWEST ARIZONA. THUS A WIND ADVISORY IS
IN EFFECT FOR THOSE AREAS. AREAS OF BLOWING DUST/SAND WILL BE
POSSIBLE AS WELL. VERY DRY AIR WILL ALSO BE USHERED IN AND THE FIRE
WEATHER WATCH WAS UPGRADED TO A RED FLAG WARNING. SEE W/W/A SECTION
BELOW FOR TIMING AND AFFECTED ZONES. THE MODELS DEPICT THE UPPER
TROUGH...INITIALLY CENTERED WELL TO OUR NORTH...TRACKING
SOUTHEASTWARD AND BECOMING A CLOSED LOW OVER THE SOUTHERN
ROCKIES/FOUR CORNERS AREA. THE GFS CONTINUES TO HAVE IT CENTERED
NORTHEAST OF THE ECMWF SOLUTION. LATEST GEM IS MORE CLOSELY ALIGNED
WITH ECMWF. THOSE MODELS ARE GENERALLY SUPPORTED BY THEIR RESPECTIVE
ENSEMBLE MEANS. THE ECMWF AND GEM SOLUTIONS HAVING THE COLD CORE
CLOSER TO OUR FORECAST AREA. MEANWHILE...VORT LOBES/JET STREAKS
ROTATE AROUND THE LOW. HOWEVER...MOISTURE AVAILABILITY OVER OUR
FORECAST AREA WILL BE QUITE MEAGER SO HELD OFF ON INTRODUCING POPS.
THERE WILL BE AT LEAST LINGERING BREEZINESS...WINDY CONDITIONS
WEDNESDAY NIGHT WITH ONE OF THOSE VORT LOBES PUSHING THROUGH. BIGGEST
BENEFIT OF THIS SYSTEM WILL BE MUCH COOLER TEMPERATURES WEDNESDAY AND
THURSDAY...AT LEAST A FEW DEGREES BELOW NORMAL BY THURSDAY.
FRIDAY THROUGH MONDAY... THE LOW SLOWLY MOVES EASTWARD FRIDAY
THROUGH SUNDAY AND HEIGHTS/THICKNESSES REBOUND. ACCORDINGLY...A
WARMING TREND BEGINS FRIDAY WITH HIGHS BACK TO THE LOW 90S ON THE
LOWER ELEVATIONS BY SUNDAY. WEAK UNDERCUTTING OF THE RIDGE OVER THE
WEST EARLY NEXT WEEK KEEPS TEMPS FLAT.
&&
.AVIATION...
SOUTH-CENTRAL ARIZONA INCLUDING KPHX...KIWA...AND KSDL...AND
SOUTHEAST CALIFORNIA AND SOUTHWEST ARIZONA INCLUDING KIPL AND KBLH...
SURFACE WINDS WILL PICK UP OVERNIGHT ACROSS SOUTHEAST CALIFORNIA AND
ALONG THE LOWER COLORADO RIVER VALLEY WITH THE APPROACH OF A STRONG
UPPER LEVEL LOW...WITH NORTHERLY WIND GUSTS OF 25-30KT POSSIBLE AT
TIMES EARLY WEDNESDAY MORNING NEAR KBLH AND KIPL. STRONGEST WINDS
AND GUSTS UP TO 40KT EXPECTED TO OCCUR AFTER 12Z WEDNESDAY MORNING
AND CONTINUE THROUGH THE DAY...THE STRONGER WIND FIELD EXPANDING
EAST ACROSS SOUTH-CENTRAL ARIZONA...WESTERLY WIND GUSTS UP TO 30KT
POSSIBLE NEAR KPHX/KIWA/KSDL WEDNESDAY AFTERNOON. LOCALIZED BLOWING
DUST COULD LIMIT VISIBILITY AT TIMES AT TAF SITES...BUT CONFIDENCE
IN TIMING AND LOCATION WILL KEEP MENTION OUT OF ALL TAFS AT THIS
TIME.
AVIATION DISCUSSION NOT UPDATED FOR AMENDED TAFS.
&&
.FIRE WEATHER...
FRIDAY THROUGH TUESDAY...HIGH PRESSURE WILL BUILD BACK OVER THE
DESERT SOUTHWEST...WITH SUBSTANTIALLY DRIER AIR ENTRENCHED ACROSS THE
REGION. THIS PATTERN WILL KEEP TEMPERATURES WARM...AND SURFACE
CONDITIONS DRY. ANTICIPATE LIGHT WINDS THROUGH THE PERIOD...DAYTIME
HUMIDITY VALUES IN THE SINGLE DIGITS...WITH WIDESPREAD POOR TO FAIR
OVERNIGHT RECOVERY IN MANY AREAS.
&&
.PSR WATCHES/WARNINGS/ADVISORIES...
AZ...RED FLAG WARNING FROM 5 AM TO 9 PM MST WEDNESDAY FOR AZZ131>133.
WIND ADVISORY FROM 2 AM TO 9 PM MST WEDNESDAY FOR AZZ020-021-025-
026.
CA...RED FLAG WARNING FROM 5 AM TO 9 PM PDT WEDNESDAY FOR CAZ231.
WIND ADVISORY FROM 2 AM TO 9 PM PDT WEDNESDAY FOR CAZ030>033.
&&
$$
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DISCUSSION...HIRSCH
PREVIOUS DISCUSSION...AJ
AVIATION....MEYERS
FIRE WEATHER...MEYERS
AREA FORECAST DISCUSSION
NWS TUCSON AZ
1006 AM MST TUE APR 14 2015
.SYNOPSIS...A FEW SHOWERS AND THUNDERSTORMS POSSIBLE AGAIN THIS
AFTERNOON. A STRONGER STORM SYSTEM DIGGING TOWARD THE REGION FROM
THE NORTHWEST WILL BRING STRONG GUSTY WINDS WEDNESDAY AND THURSDAY
ALONG WITH A SHOT OF MUCH COOLER AIR. UNSEASONABLY COLD OVERNIGHT
LOWS IN SOME LOCATIONS ARE POSSIBLE LATE IN THE WEEK.
&&
.DISCUSSION...STILL LOOKING AT SOME RESIDUAL MOISTURE ACROSS THE
AREA. MODELS SUGGEST A FEW SHOWERS OR THUNDERSTORMS POSSIBLE THIS
AFTERNOON MAINLY IN THE MOUNTAINS. OTHERWISE...MOSTLY CLEAR. CURRENT
FORECAST LOOKED ON TRACK SO NO UPDATES NECESSARY THIS MORNING.
PLEASE REFER TO THE ADDITIONAL SECTIONS ABOUT THE UPCOMING WEATHER
CHANGES THIS WEEK.
&&
.AVIATION...VALID THRU 15/18Z.
SURFACE WINDS GENERALLY LESS THAN 12 KTS THIS MORNING UNDER MOSTLY
CLEAR SKIES. ISOLATED -SHRA/-TSRA POSSIBLE THIS AFTERNOON. WLY WINDS
8-12 KTS DURING THE DAY WITH SCT CLOUDS AOA 15K FT AGL. GUSTY ERRATIC
OUTFLOWS AT TIMES ASSOCIATED CONVECTION. NORMAL DIURNAL WIND TRENDS
RETURNING OVERNIGHT. A STRONG SYSTEM DIGGING DOWN FROM THE NORTH
WILL BRING WINDY CONDITIONS TO THE AREA WEDNESDAY. AVIATION
DISCUSSION NOT UPDATED FOR TAF AMENDMENTS.
&&
.FIRE WEATHER...BECOMING PARTLY CLOUDY WITH ISOLATED SHOWERS AND
THUNDERSTORMS AROUND THE AREA TODAY. STRONG GUSTY OUTFLOWS POSSIBLE
WITH SOME STORMS.
A DEVELOPING LOW PRESSURE SYSTEM IS EXPECTED TO DROP OUT OF THE
PACIFIC NW TONIGHT AND THEN MOVE OVER NORTHEAST ARIZONA LATE
WEDNESDAY INTO THURSDAY MORNING. THIS SYSTEM IS EXPECTED TO SPREAD
STRONG WINDS AND DRY AIR ACROSS THE AREA WEDNESDAY INTO THURSDAY AS
WELL AS MUCH COOLER TEMPERATURES THURSDAY. STRONG AND GUSTY WESTERLY
WINDS WEDNESDAY WITH FALLING RH VALUES THROUGH THE DAY ARE EXPECTED
TO CAUSE CRITICAL FIRE WEATHER CONDITIONS BY WEDNESDAY AFTERNOON
ACROSS MOST OF SOUTHEAST ARIZONA. A RED FLAG WARNING HAS BEEN ISSUED
FOR MOST OF SOUTHEAST ARIZONA FROM LATE WEDNESDAY MORNING INTO
WEDNESDAY EVENING.
THE DRY AIR WILL BE IN PLACE ON THURSDAY BUT THE WINDS WILL BE
SLIGHTLY WEAKER. WE WILL CONTINUE TO EVALUATE THURSDAY FOR ANY
POSSIBLE FIRE WEATHER CONCERNS. WINDS WILL DIMINISH SOMEWHAT BY
FRIDAY AFTERNOON INTO THE COMING WEEKEND WITH DRY CONDITIONS ACROSS
THE AREA.
&&
.PREV DISCUSSION...WE CONTINUE TO HANG ON TO A REASONABLE AMOUNT OF
MOISTURE FOR A PERIOD IN BETWEEN SYSTEMS...WITH SURFACE DEW POINTS
IN THE 30S AND 40S ALONG WITH PRECIPITABLE WATER VALUES AROUND .5 TO
.7 INCHES. SHORT RANGE HIGH RESOLUTION MODELS SUCH AS THE HRRR AGAIN
SPRINKLE CONVECTION AROUND SOUTHEAST AND SOUTH CENTRAL ARIZONA THIS
AFTERNOON. A PARTICULAR FOCUS IS SETTING UP ASSOCIATED WITH A MID
LEVEL INFLECTION THROUGH CENTRAL PIMA COUNTY THIS AFTERNOON...SO WE
HAVE ADDED ISOLATED THUNDERSTORMS TO SOME AREAS WEST OF TUCSON AS
WELL.
STILL ON TRACK FOR A SIGNIFICANT SPLIT OF ENERGY FROM THE NORTHWEST
INTO THE FOUR CORNERS REGION OVER THE NEXT 48 HOURS. THIS WILL BRING
STRONG GUSTY WINDS ACROSS THE ENTIRE AREA WEDNESDAY WITH VERY DRY
AIR BEHIND AN ASSOCIATED COLD FRONT SWEEPING DOWN FROM THE NORTH
DURING THE DAY WEDNESDAY. THE RAPIDLY DRYING CONDITIONS AROUND MID
DAY THROUGH THE AFTERNOON AND EVENING IS LEADING US TO ISSUE A RED
FLAG WARNING FOR WEDNESDAY IN ASSOCIATION WITH FIRE WEATHER
HEADLINES ISSUED BY PSR. PLEASE SEE THE FIRE WEATHER DISCUSSION
BELOW FOR ADDITIONAL DETAILS.
THE LOW WILL THEN SAG INTO NORTHEAST ARIZONA AND NORTHWEST NEW
MEXICO THURSDAY...HOWEVER A DRY INLAND TRAJECTORY ON THIS SYSTEM
WILL SEE LIMITED MOISTURE FOR OUR AREA. VERY COOL AIR HOWEVER...WITH
TEMPERATURES AT LEAST 10 DEGREES BELOW CLIMATOLOGY THURSDAY.
UNSEASONABLY COOL OVERNIGHT LOWS THURSDAY NIGHT AND FRIDAY
NIGHT...WITH LATE SEASON FREEZING TEMPERATURES POSSIBLE IN COLDER
EASTERN VALLEY LOCATIONS INCLUDING SULPHUR SPRINGS VALLEY IN COCHISE
COUNTY. A DEFINITE CONCERN FOR AGRICULTURE IN SOUTHEAST ARIZONA.
&&
.TWC WATCHES/WARNINGS/ADVISORIES...RED FLAG WARNING WEDNESDAY FROM
11 AM UNTIL 8 PM FOR MUCH OF SOUTHEAST ARIZONA INCLUDING FIRE
WEATHER ZONES AZZ150-151...NORTHERN PORTIONS OF 152....AND
SOUTHERN PORTIONS OF 153.
&&
$$
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AREA FORECAST DISCUSSION
NWS PHOENIX AZ
935 AM MST TUE APR 14 2015
.SYNOPSIS... THERE WILL BE A SLIGHT CHANCE OF THUNDERSTORMS OVER
PORTIONS OF SOUTH-CENTRAL ARIZONA TODAY BUT WITH LITTLE IF ANY
RAINFALL. OTHERWISE EXPECT ANOTHER WARM DAY. A DRY COLD FRONT PUSHES
THROUGH SOUTHEAST CALIFORNIA AND ARIZONA TUESDAY NIGHT AND
WEDNESDAY. THIS WILL LEAD TO VERY WINDY CONDITIONS OVER SOUTHEAST
CALIFORNIA AND WESTERN ARIZONA. WINDS WILL NOT BE QUITE AS STRONG
OVER SOUTH-CENTRAL ARIZONA. THE FRONTAL PASSAGE WILL ALSO LEAD TO
MUCH COOLER TEMPERATURES...DIPPING BELOW THE NORMAL BY THURSDAY.
EXPECT A WARMING TREND FRIDAY THROUGH SUNDAY WITH LITTLE CHANGE
MONDAY.
&&
.DISCUSSION... LATEST RAP STREAMLINE ANALYSIS SHOWS A LARGE TROUGH
TRANSLATING EASTWARD THROUGH THE GREAT BASIN TOWARDS UT. AHEAD OF
THIS TROUGH...SKIES ARE SUNNY ACROSS THE DESERT SOUTHWEST AND
ANOTHER DAY OF ABOVE AVERAGE TEMPERATURES IS EXPECTED.
MEANWHILE...LATEST TWC SOUNDING INDICATES THAT RICHER MOISTURE
RESIDES BELOW 600 MB IN THE WAKE OF THE TROUGH ACROSS NM. SOME OF
THE WRF-BASED GUIDANCE HAS PICKED UP ON THIS MOISTURE AND SUGGESTS
THAT ISOLATED CONVECTION WILL DEVELOP THIS AFTERNOON. CU IS ALREADY
FORMING ACROSS THE WHITE MOUNTAINS AND THE GENERAL CONSENSUS AMONGST
THE HI-RES GUIDANCE IS THAT THE THREAT OF SHOWERS AND THUNDERSTORMS
WILL BE CONFINED TO SE AZ. POPS WERE LOWERED FOR PINAL COUNTY FOR
THIS AFTERNOON. NEVERTHELESS...THE CHANCE FOR PRECIPITATION IS NON-
ZERO BUT LESS THAN 10 PERCENT.
&&
.PREVIOUS DISCUSSION... TONIGHT THROUGH THURSDAY...THE BRUNT OF THE
AFOREMENTIONED PACIFIC LOW PRESSURE SYSTEM WILL INITIALLY AFFECT
AREAS WELL NORTH OF OUR FORECAST AREA. HOWEVER...THERE WILL BE A DRY
COLD FRONT THAT PUSHES THROUGH SOUTHEAST CALIFORNIA AND ARIZONA
BEGINNING TUESDAY NIGHT AND CONTINUING WEDNESDAY. VERY STRONG
NORTHERLY WINDS IN THE LOWER LEVELS WILL BE ASSOCIATED WITH THE
FRONTAL PASSAGE...MOST NOTABLY FOR WESTERN PORTIONS OF OUR FORECAST
AREA IN SOUTHEAST CALIFORNIA AND SOUTHWEST ARIZONA. THUS A WIND
ADVISORY IS IN EFFECT FOR THOSE AREAS. AREAS OF BLOWING DUST/SAND
WILL BE POSSIBLE AS WELL. VERY DRY AIR WILL ALSO BE USHERED IN AND
THE FIRE WEATHER WATCH WAS UPGRADED TO A RED FLAG WARNING. SEE W/W/A
SECTION BELOW FOR TIMING AND AFFECTED ZONES. THE MODELS DEPICT THE
UPPER TROUGH...INITIALLY CENTERED WELL TO OUR NORTH...TRACKING
SOUTHEASTWARD AND BECOMING A CLOSED LOW OVER THE SOUTHERN
ROCKIES/FOUR CORNERS AREA. THE GFS CONTINUES TO HAVE IT CENTERED
NORTHEAST OF THE ECMWF SOLUTION. LATEST GEM IS MORE CLOSELY ALIGNED
WITH ECMWF. THOSE MODELS ARE GENERALLY SUPPORTED BY THEIR RESPECTIVE
ENSEMBLE MEANS. THE ECMWF AND GEM SOLUTIONS HAVING THE COLD CORE
CLOSER TO OUR FORECAST AREA. MEANWHILE...VORT LOBES/JET STREAKS
ROTATE AROUND THE LOW. HOWEVER...MOISTURE AVAILABILITY OVER OUR
FORECAST AREA WILL BE QUITE MEAGER SO HELD OFF ON INTRODUCING POPS.
THERE WILL BE AT LEAST LINGERING BREEZINESS...WINDY CONDITIONS
WEDNESDAY NIGHT WITH ONE OF THOSE VORT LOBES PUSHING THROUGH.
BIGGEST BENEFIT OF THIS SYSTEM WILL BE MUCH COOLER TEMPERATURES
WEDNESDAY AND THURSDAY...AT LEAST A FEW DEGREES BELOW NORMAL BY
THURSDAY.
FRIDAY THROUGH MONDAY... THE LOW SLOWLY MOVES EASTWARD FRIDAY
THROUGH SUNDAY AND HEIGHTS/THICKNESSES REBOUND. ACCORDINGLY...A
WARMING TREND BEGINS FRIDAY WITH HIGHS BACK TO THE LOW 90S ON THE
LOWER ELEVATIONS BY SUNDAY. WEAK UNDERCUTTING OF THE RIDGE OVER THE
WEST EARLY NEXT WEEK KEEPS TEMPS FLAT.
&&
.AVIATION...
SOUTH-CENTRAL ARIZONA INCLUDING KPHX...KIWA...AND KSDL...AND
SOUTHEAST CALIFORNIA AND SOUTHWEST ARIZONA INCLUDING KIPL AND KBLH...
CERTAINLY LOOKING AT A QUIET WEATHER DAY ACROSS SOUTHEAST CALIFORNIA
ALTHOUGH WINDS WILL PICK UP EARLY WEDNESDAY MORNING. MEANWHILE AROUND
PHOENIX WINDS WILL FOLLOW TYPICAL DIURNAL TRENDS WITH MOSTLY CLEAR
SKIES. COULD BE SOME DISTANT CU TO THE SOUTH/EAST OF
PHOENIX...POSSIBLY SOME VIRGA AND/OR ISOLATED SHOWERS AS WELL.
SHOULD NOT IMPACT THE TERMINALS DIRECTLY BUT GIVEN THE VERY DRY SUB-
CLOUD LAYER...WILL NEED TO MONITOR ANY SHOWERS FOR BLDU.
AVIATION DISCUSSION NOT UPDATED FOR AMENDED TAFS.
&&
.FIRE WEATHER...
THURSDAY THROUGH MONDAY...
AN AREA OF LOW PRESSURE WILL CONTINUE TO MOVE THROUGH THE FOUR
CORNERS REGION THURSDAY AND FRIDAY. HOWEVER...DRY AIR WILL REMAIN
IN PLACE INTO THE WEEKEND...AND WITH VERY LITTLE ATMOSPHERIC
MOISTURE...THERE WILL BE NO PRECIPITATION...JUST SOME PASSING HIGH
CLOUDS. WINDS WILL BE MUCH LIGHTER THROUGH FRIDAY INTO THE WEEKEND.
EXPECT FAIR/POOR OVERNIGHT RECOVERIES DURING THE PERIOD.
&&
.PSR WATCHES/WARNINGS/ADVISORIES...
AZ...RED FLAG WARNING FROM 5 AM TO 9 PM MST WEDNESDAY FOR AZZ131-132.
WIND ADVISORY FROM 2 AM TO 9 PM MST WEDNESDAY FOR AZZ020-021-025-
026.
CA...RED FLAG WARNING FROM 5 AM TO 9 PM PDT WEDNESDAY FOR CAZ231.
WIND ADVISORY FROM 2 AM TO 9 PM PDT WEDNESDAY FOR CAZ030>033.
&&
$$
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DISCUSSION...HIRSCH
PREVIOUS DISCUSSION...AJ
AVIATION...LEINS
FIRE WEATHER...LEINS/MEYERS
AREA FORECAST DISCUSSION...UPDATED
NWS PHOENIX AZ
418 AM MST TUE APR 14 2015
.UPDATE...UPDATED AVIATION...FIRE WEATHER...AND WWA SECTIONS...
&&
.SYNOPSIS...
THERE WILL BE A SLIGHT CHANCE OF THUNDERSTORMS OVER
PORTIONS OF SOUTH-CENTRAL ARIZONA TODAY BUT WITH LITTLE IF ANY
RAINFALL. OTHERWISE EXPECT ANOTHER WARM DAY. A DRY COLD FRONT PUSHES
THROUGH SOUTHEAST CALIFORNIA AND ARIZONA TUESDAY NIGHT AND
WEDNESDAY. THIS WILL LEAD TO VERY WINDY CONDITIONS OVER SOUTHEAST
CALIFORNIA AND WESTERN ARIZONA. WINDS WILL NOT BE QUITE AS STRONG
OVER SOUTH-CENTRAL ARIZONA. THE FRONTAL PASSAGE WILL ALSO LEAD TO
MUCH COOLER TEMPERATURES...DIPPING BELOW THE NORMAL BY THURSDAY.
EXPECT A WARMING TREND FRIDAY THROUGH SUNDAY WITH LITTLE CHANGE
MONDAY.
&&
.DISCUSSION...
TODAY...ISOLATED THUNDERSTORMS MONDAY EVENING OVER SOUTHEAST ARIZONA
REFLECTED THE PRESENCE OF JUST ENOUGH MOISTURE AND
INSTABILITY...ALONG WITH A SUBTLE PERTURBATION...TO GET THUNDERSTORMS
TO FORM. THIS WILL BE THE CASE AGAIN LATER TODAY...ESPECIALLY AS
SOUTHEAST AND SOUTHERLY LOWER LEVEL WINDS PROVIDE FOR SOME MOIST
ADVECTION AS EVIDENT IN MODEL SOUNDINGS. FOR TODAY THE PERTURBATION
WILL NOT BE ASSOCIATED WITH THE UPPER LOW TO OUR EAST BUT INSTEAD A
SHORT WAVE AHEAD OF THE PACIFIC LOW PRESSURE SYSTEM ALREADY MOVING
ASHORE EARLY THIS MORNING OVER NORTHERN CALIFORNIA AND THE PACIFIC
NORTHWEST. NAM BOUNDARY LAYER CAPE IS MODEST BUT MORE WIDESPREAD FOR
LATE THIS AFTERNOON THAN IT WAS FOR YESTERDAY. HRRR HAS HAD SEVERAL
RUNS DEPICTING ISOLATED-SCATTERED CONVECTION OVER CENTRAL AND EASTERN
ARIZONA THIS AFTERNOON THOUGH IT APPEARS TO BE THE MOST AGGRESSIVE OF
THE HI-RES MODELS...ESPECIALLY COMPARED TO LOCAL WRF. LATEST SSEO
HINTS AT CONVECTION AFFECTING OUR EASTERN AREAS. SPC HAS GENERAL
THUNDER OVER THE EASTERN THIRD OF ARIZONA. GIVEN ALL THIS...ADDED A
SLIGHT CHANCE OF THUNDERSTORMS THIS AFTERNOON AND EVENING OVER OUR
PORTIONS OF PINAL AND GILA COUNTIES. ALSO ADDED A MENTION OF PATCHY
BLOWING DUST FOR OUR PORTION OF PINAL COUNTY AS THUNDERSTORMS...IF
ANY...WILL BE ABLE TO PRODUCE SOME NOTABLE OUTFLOW GIVEN INVERTED V
SOUNDINGS.
TONIGHT THROUGH THURSDAY...THE BRUNT OF THE AFOREMENTIONED PACIFIC
LOW PRESSURE SYSTEM WILL INITIALLY AFFECT AREAS WELL NORTH OF OUR
FORECAST AREA. HOWEVER...THERE WILL BE A DRY COLD FRONT THAT PUSHES
THROUGH SOUTHEAST CALIFORNIA AND ARIZONA BEGINNING TUESDAY NIGHT AND
CONTINUING WEDNESDAY. VERY STRONG NORTHERLY WINDS IN THE LOWER
LEVELS WILL BE ASSOCIATED WITH THE FRONTAL PASSAGE...MOST NOTABLY
FOR WESTERN PORTIONS OF OUR FORECAST AREA IN SOUTHEAST CALIFORNIA
AND SOUTHWEST ARIZONA. THUS A WIND ADVISORY IS IN EFFECT FOR THOSE
AREAS. AREAS OF BLOWING DUST/SAND WILL BE POSSIBLE AS WELL. VERY DRY
AIR WILL ALSO BE USHERED IN AND THE FIRE WEATHER WATCH WAS UPGRADED
TO A RED FLAG WARNING. SEE W/W/A SECTION BELOW FOR TIMING AND
AFFECTED ZONES. THE MODELS DEPICT THE UPPER TROUGH...INITIALLY
CENTERED WELL TO OUR NORTH...TRACKING SOUTHEASTWARD AND BECOMING A
CLOSED LOW OVER THE SOUTHERN ROCKIES/FOUR CORNERS AREA. THE GFS
CONTINUES TO HAVE IT CENTERED NORTHEAST OF THE ECMWF SOLUTION.
LATEST GEM IS MORE CLOSELY ALIGNED WITH ECMWF. THOSE MODELS ARE
GENERALLY SUPPORTED BY THEIR RESPECTIVE ENSEMBLE MEANS. THE ECMWF
AND GEM SOLUTIONS HAVING THE COLD CORE CLOSER TO OUR FORECAST AREA.
MEANWHILE...VORT LOBES/JET STREAKS ROTATE AROUND THE LOW.
HOWEVER...MOISTURE AVAILABILITY OVER OUR FORECAST AREA WILL BE QUITE
MEAGER SO HELD OFF ON INTRODUCING POPS. THERE WILL BE AT LEAST
LINGERING BREEZINESS...WINDY CONDITIONS WEDNESDAY NIGHT WITH ONE OF
THOSE VORT LOBES PUSHING THROUGH. BIGGEST BENEFIT OF THIS SYSTEM WILL
BE MUCH COOLER TEMPERATURES WEDNESDAY AND THURSDAY...AT LEAST A FEW
DEGREES BELOW NORMAL BY THURSDAY.
FRIDAY THROUGH MONDAY... THE LOW SLOWLY MOVES EASTWARD FRIDAY
THROUGH SUNDAY AND HEIGHTS/THICKNESSES REBOUND. ACCORDINGLY...A
WARMING TREND BEGINS FRIDAY WITH HIGHS BACK TO THE LOW 90S ON THE
LOWER ELEVATIONS BY SUNDAY. WEAK UNDERCUTTING OF THE RIDGE OVER THE
WEST EARLY NEXT WEEK KEEPS TEMPS FLAT.
&&
.AVIATION...
SOUTH-CENTRAL ARIZONA INCLUDING KPHX...KIWA...AND KSDL...AND
SOUTHEAST CALIFORNIA AND SOUTHWEST ARIZONA INCLUDING KIPL AND KBLH...
CERTAINLY LOOKING AT A QUIET WEATHER DAY ACROSS SOUTHEAST CALIFORNIA
ALTHOUGH WINDS WILL PICK UP EARLY WEDNESDAY MORNING. MEANWHILE AROUND
PHOENIX WINDS WILL FOLLOW TYPICAL DIURNAL TRENDS WITH MOSTLY CLEAR
SKIES. COULD BE SOME DISTANT CU TO THE SOUTH/EAST OF
PHOENIX...POSSIBLY SOME VIRGA AND/OR ISOLATED SHOWERS AS WELL.
SHOULD NOT IMPACT THE TERMINALS DIRECTLY BUT GIVEN THE VERY DRY SUB-
CLOUD LAYER...WILL NEED TO MONITOR ANY SHOWERS FOR BLDU.
AVIATION DISCUSSION NOT UPDATED FOR AMENDED TAFS.
&&
.FIRE WEATHER...
THURSDAY THROUGH MONDAY...
AN AREA OF LOW PRESSURE WILL CONTINUE TO MOVE THROUGH THE FOUR
CORNERS REGION THURSDAY AND FRIDAY. HOWEVER...DRY AIR WILL REMAIN
IN PLACE INTO THE WEEKEND...AND WITH VERY LITTLE ATMOSPHERIC
MOISTURE...THERE WILL BE NO PRECIPITATION...JUST SOME PASSING HIGH
CLOUDS. WINDS WILL BE MUCH LIGHTER THROUGH FRIDAY INTO THE WEEKEND.
EXPECT FAIR/POOR OVERNIGHT RECOVERIES DURING THE PERIOD.
&&
.PSR WATCHES/WARNINGS/ADVISORIES...
AZ...RED FLAG WARNING FROM 5 AM TO 9 PM MST WEDNESDAY FOR AZZ131-132.
WIND ADVISORY FROM 2 AM TO 9 PM MST WEDNESDAY FOR AZZ020-021-025-
026.
CA...RED FLAG WARNING FROM 5 AM TO 9 PM PDT WEDNESDAY FOR CAZ231.
WIND ADVISORY FROM 2 AM TO 9 PM PDT WEDNESDAY FOR CAZ030>033.
&&
$$
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DISCUSSION...AJ
AVIATION...LEINS
FIRE WEATHER...LEINS/MEYERS
AREA FORECAST DISCUSSION
NWS PHOENIX AZ
410 AM MST MON APR 13 2015
.SYNOPSIS... THERE WILL BE A SLIGHT CHANCE OF THUNDERSTORMS OVER
PORTIONS OF SOUTH-CENTRAL ARIZONA TODAY BUT WITH LITTLE IF ANY
RAINFALL. OTHERWISE EXPECT ANOTHER WARM DAY. A DRY COLD FRONT PUSHES
THROUGH SOUTHEAST CALIFORNIA AND ARIZONA TUESDAY NIGHT AND
WEDNESDAY. THIS WILL LEAD TO VERY WINDY CONDITIONS OVER SOUTHEAST
CALIFORNIA AND WESTERN ARIZONA. WINDS WILL NOT BE QUITE AS STRONG
OVER SOUTH-CENTRAL ARIZONA. THE FRONTAL PASSAGE WILL ALSO LEAD TO
MUCH COOLER TEMPERATURES...DIPPING BELOW THE NORMAL BY THURSDAY.
EXPECT A WARMING TREND FRIDAY THROUGH SUNDAY WITH LITTLE CHANGE
MONDAY.
&&
.DISCUSSION...
TODAY...ISOLATED THUNDERSTORMS MONDAY EVENING OVER SOUTHEAST ARIZONA
REFLECTED THE PRESENCE OF JUST ENOUGH MOISTURE AND
INSTABILITY...ALONG WITH A SUBTLE PERTURBATION...TO GET
THUNDERSTORMS TO FORM. THIS WILL BE THE CASE AGAIN LATER
TODAY...ESPECIALLY AS SOUTHEAST AND SOUTHERLY LOWER LEVEL WINDS
PROVIDE FOR SOME MOIST ADVECTION AS EVIDENT IN MODEL SOUNDINGS. FOR
TODAY THE PERTURBATION WILL NOT BE ASSOCIATED WITH THE UPPER LOW TO
OUR EAST BUT INSTEAD A SHORT WAVE AHEAD OF THE PACIFIC LOW PRESSURE
SYSTEM ALREADY MOVING ASHORE EARLY THIS MORNING OVER NORTHERN
CALIFORNIA AND THE PACIFIC NORTHWEST. NAM BOUNDARY LAYER CAPE IS
MODEST BUT MORE WIDESPREAD FOR LATE THIS AFTERNOON THAN IT WAS FOR
YESTERDAY. HRRR HAS HAD SEVERAL RUNS DEPICTING ISOLATED-SCATTERED
CONVECTION OVER CENTRAL AND EASTERN ARIZONA THIS AFTERNOON THOUGH IT
APPEARS TO BE THE MOST AGGRESSIVE OF THE HI-RES MODELS...ESPECIALLY
COMPARED TO LOCAL WRF. LATEST SSEO HINTS AT CONVECTION AFFECTING OUR
EASTERN AREAS. SPC HAS GENERAL THUNDER OVER THE EASTERN THIRD OF
ARIZONA. GIVEN ALL THIS...ADDED A SLIGHT CHANCE OF THUNDERSTORMS
THIS AFTERNOON AND EVENING OVER OUR PORTIONS OF PINAL AND GILA
COUNTIES. ALSO ADDED A MENTION OF PATCHY BLOWING DUST FOR OUR
PORTION OF PINAL COUNTY AS THUNDERSTORMS...IF ANY...WILL BE ABLE TO
PRODUCE SOME NOTABLE OUTFLOW GIVEN INVERTED V SOUNDINGS.
TONIGHT THROUGH THURSDAY...THE BRUNT OF THE AFOREMENTIONED PACIFIC
LOW PRESSURE SYSTEM WILL INITIALLY AFFECT AREAS WELL NORTH OF OUR
FORECAST AREA. HOWEVER...THERE WILL BE A DRY COLD FRONT THAT PUSHES
THROUGH SOUTHEAST CALIFORNIA AND ARIZONA BEGINNING TUESDAY NIGHT AND
CONTINUING WEDNESDAY. VERY STRONG NORTHERLY WINDS IN THE LOWER
LEVELS WILL BE ASSOCIATED WITH THE FRONTAL PASSAGE...MOST NOTABLY
FOR WESTERN PORTIONS OF OUR FORECAST AREA IN SOUTHEAST CALIFORNIA
AND SOUTHWEST ARIZONA. THUS A WIND ADVISORY IS IN EFFECT FOR THOSE
AREAS. AREAS OF BLOWING DUST/SAND WILL BE POSSIBLE AS WELL. VERY DRY
AIR WILL ALSO BE USHERED IN AND THE FIRE WEATHER WATCH WAS UPGRADED
TO A RED FLAG WARNING. SEE W/W/A SECTION BELOW FOR TIMING AND
AFFECTED ZONES. THE MODELS DEPICT THE UPPER TROUGH...INITIALLY
CENTERED WELL TO OUR NORTH...TRACKING SOUTHEASTWARD AND BECOMING A
CLOSED LOW OVER THE SOUTHERN ROCKIES/FOUR CORNERS AREA. THE GFS
CONTINUES TO HAVE IT CENTERED NORTHEAST OF THE ECMWF SOLUTION.
LATEST GEM IS MORE CLOSELY ALIGNED WITH ECMWF. THOSE MODELS ARE
GENERALLY SUPPORTED BY THEIR RESPECTIVE ENSEMBLE MEANS. THE ECMWF
AND GEM SOLUTIONS HAVING THE COLD CORE CLOSER TO OUR FORECAST AREA.
MEANWHILE...VORT LOBES/JET STREAKS ROTATE AROUND THE LOW.
HOWEVER...MOISTURE AVAILABILITY OVER OUR FORECAST AREA WILL BE QUITE
MEAGER SO HELD OFF ON INTRODUCING POPS. THERE WILL BE AT LEAST
LINGERING BREEZINESS...WINDY CONDITIONS WEDNESDAY NIGHT WITH ONE OF
THOSE VORT LOBES PUSHING THROUGH. BIGGEST BENEFIT OF THIS SYSTEM WILL
BE MUCH COOLER TEMPERATURES WEDNESDAY AND THURSDAY...AT LEAST A FEW
DEGREES BELOW NORMAL BY THURSDAY.
FRIDAY THROUGH MONDAY... THE LOW SLOWLY MOVES EASTWARD FRIDAY
THROUGH SUNDAY AND HEIGHTS/THICKNESSES REBOUND. ACCORDINGLY...A
WARMING TREND BEGINS FRIDAY WITH HIGHS BACK TO THE LOW 90S ON THE
LOWER ELEVATIONS BY SUNDAY. WEAK UNDERCUTTING OF THE RIDGE OVER THE
WEST EARLY NEXT WEEK KEEPS TEMPS FLAT.
&&
.AVIATION...
SOUTH-CENTRAL ARIZONA INCLUDING KPHX...KIWA...AND KSDL...AND
SOUTHEAST CALIFORNIA AND SOUTHWEST ARIZONA INCLUDING KIPL AND KBLH...
NO SIGNIFICANT AVIATION CONCERNS THROUGH TUESDAY AFTERNOON UNDER
MOSTLY CLEAR SKIES. SFC WINDS WILL FOLLOW TYPICAL DIURNAL PATTERNS
THROUGH TUESDAY MORNING...BECOMING MORE GUSTY FROM THE SOUTH AND
WEST TUESDAY AFTERNOON. OCCASIONAL GUSTS IN A 20 TO 25 KT RANGE WILL
BE COMMON LATER TUESDAY AFTERNOON.
AVIATION DISCUSSION NOT UPDATED FOR AMENDED TAFS.
&&
.FIRE WEATHER...
THURSDAY THROUGH MONDAY...
AN AREA OF LOW PRESSURE WILL CONTINUE TO MOVE THROUGH THE FOUR
CORNERS REGION THURSDAY AND FRIDAY. HOWEVER...DRY AIR WILL REMAIN
IN PLACE INTO THE WEEKEND...AND WITH VERY LITTLE ATMOSPHERIC
MOISTURE...THERE WILL BE NO PRECIPITATION...JUST SOME PASSING HIGH
CLOUDS. WINDS WILL BE MUCH LIGHTER THROUGH FRIDAY INTO THE WEEKEND.
EXPECT FAIR/POOR OVERNIGHT RECOVERIES DURING THE PERIOD.
&&
.PSR WATCHES/WARNINGS/ADVISORIES...
AZ...RED FLAG WARNING FROM 5 AM TO 11 PM MST WEDNESDAY FOR
AZZ131-132.
WIND ADVISORY FROM 2 AM TO 9 PM MST WEDNESDAY FOR AZZ020-021-
025-026.
CA...RED FLAG WARNING FROM 5 AM TO 11 PM PDT WEDNESDAY FOR CAZ231.
WIND ADVISORY FROM 2 AM TO 9 PM PDT WEDNESDAY FOR CAZ030>033.
&&
$$
VISIT US ON FACEBOOK...TWITTER...AND AT WEATHER.GOV/PHOENIX
DISCUSSION...AJ
AVIATION....MO
FIRE WEATHER...MEYERS
AREA FORECAST DISCUSSION
NWS TUCSON AZ
300 AM MST TUE APR 14 2015
.SYNOPSIS...A FEW SHOWERS AND THUNDERSTORMS POSSIBLE AGAIN THIS
AFTERNOON. A STRONGER STORM SYSTEM DIGGING TOWARD THE REGION FROM
THE NORTHWEST WILL BRING STRONG GUSTY WINDS WEDNESDAY AND THURSDAY
ALONG WITH A SHOT OF MUCH COOLER AIR. UNSEASONABLY COLD OVERNIGHT
LOWS IN SOME LOCATIONS ARE POSSIBLE LATE IN THE WEEK.
&&
.DISCUSSION...WE CONTINUE TO HANG ON TO A REASONABLE AMOUNT OF
MOISTURE FOR A PERIOD IN BETWEEN SYSTEMS...WITH SURFACE DEW POINTS
IN THE 30S AND 40S ALONG WITH PRECIPITABLE WATER VALUES AROUND .5 TO
.7 INCHES. SHORT RANGE HIGH RESOLUTION MODELS SUCH AS THE HRRR AGAIN
SPRINKLE CONVECTION AROUND SOUTHEAST AND SOUTH CENTRAL ARIZONA THIS
AFTERNOON. A PARTICULAR FOCUS IS SETTING UP ASSOCIATED WITH A MID
LEVEL INFLECTION THROUGH CENTRAL PIMA COUNTY THIS AFTERNOON...SO WE
HAVE ADDED ISOLATED THUNDERSTORMS TO SOME AREAS WEST OF TUCSON AS
WELL.
STILL ON TRACK FOR A SIGNIFICANT SPLIT OF ENERGY FROM THE NORTHWEST
INTO THE FOUR CORNERS REGION OVER THE NEXT 48 HOURS. THIS WILL BRING
STRONG GUSTY WINDS ACROSS THE ENTIRE AREA WEDNESDAY WITH VERY DRY
AIR BEHIND AN ASSOCIATED COLD FRONT SWEEPING DOWN FROM THE NORTH
DURING THE DAY WEDNESDAY. THE RAPIDLY DRYING CONDITIONS AROUND MID
DAY THROUGH THE AFTERNOON AND EVENING IS LEADING US TO ISSUE A RED
FLAG WARNING FOR WEDNESDAY IN ASSOCIATION WITH FIRE WEATHER
HEADLINES ISSUED BY PSR. PLEASE SEE THE FIRE WEATHER DISCUSSION
BELOW FOR ADDITIONAL DETAILS.
THE LOW WILL THEN SAG INTO NORTHEAST ARIZONA AND NORTHWEST NEW
MEXICO THURSDAY...HOWEVER A DRY INLAND TRAJECTORY ON THIS SYSTEM
WILL SEE LIMITED MOISTURE FOR OUR AREA. VERY COOL AIR HOWEVER...WITH
TEMPERATURES AT LEAST 10 DEGREES BELOW CLIMATOLOGY THURSDAY.
UNSEASONABLY COOL OVERNIGHT LOWS THURSDAY NIGHT AND FRIDAY
NIGHT...WITH LATE SEASON FREEZING TEMPERATURES POSSIBLE IN COLDER
EASTERN VALLEY LOCATIONS INCLUDING SULPHUR SPRINGS VALLEY IN COCHISE
COUNTY. A DEFINITE CONCERN FOR AGRICULTURE IN SOUTHEAST ARIZONA.
&&
.AVIATION...VALID THRU 15/12Z.
SURFACE WINDS GENERALLY LESS THAN 12 KTS THIS MORNING UNDER MOSTLY
CLEAR SKIES. ISOLATED -SHRA/-TSRA POSSIBLE THIS AFTERNOON. WLY WINDS
8-12 KTS DURING THE DAY WITH SCT CLOUDS AOA 15K FT AGL. GUSTY ERRATIC
OUTFLOWS AT TIMES ASSOCIATED CONVECTION. NORMAL DIURNAL WIND TRENDS
RETURNING OVERNIGHT. A STRONG SYSTEM DIGGING DOWN FROM THE NORTH
WILL BRING WINDY CONDITIONS TO THE AREA WEDNESDAY. AVIATION
DISCUSSION NOT UPDATED FOR TAF AMENDMENTS.
&&
.FIRE WEATHER...BECOMING PARTLY CLOUDY WITH ISOLATED SHOWERS AND
THUNDERSTORMS AROUND THE AREA TODAY. STRONG GUSTY OUTFLOWS POSSIBLE
WITH SOME STORMS.
A DEVELOPING LOW PRESSURE SYSTEM IS EXPECTED TO DROP OUT OF THE
PACIFIC NW TONIGHT AND THEN MOVE OVER NORTHEAST ARIZONA LATE
WEDNESDAY INTO THURSDAY MORNING. THIS SYSTEM IS EXPECTED TO SPREAD
STRONG WINDS AND DRY AIR ACROSS THE AREA WEDNESDAY INTO THURSDAY AS
WELL AS MUCH COOLER TEMPERATURES THURSDAY. STRONG AND GUSTY WESTERLY
WINDS WEDNESDAY WITH FALLING RH VALUES THROUGH THE DAY ARE EXPECTED
TO CAUSE CRITICAL FIRE WEATHER CONDITIONS BY WEDNESDAY AFTERNOON
ACROSS MOST OF SOUTHEAST ARIZONA. A RED FLAG WARNING HAS BEEN ISSUED
FOR MOST OF SOUTHEAST ARIZONA FROM LATE WEDNESDAY MORNING INTO
WEDNESDAY EVENING.
THE DRY AIR WILL BE IN PLACE ON THURSDAY BUT THE WINDS WILL BE
SLIGHTLY WEAKER. WE WILL CONTINUE TO EVALUATE THURSDAY FOR ANY
POSSIBLE FIRE WEATHER CONCERNS. WINDS WILL DIMINISH SOMEWHAT BY
FRIDAY AFTERNOON INTO THE COMING WEEKEND WITH DRY CONDITIONS ACROSS
THE AREA.
&&
.TWC WATCHES/WARNINGS/ADVISORIES...RED FLAG WARNING WEDNESDAY FROM
11 AM UNTIL 8 PM FOR MUCH OF SOUTHEAST ARIZONA INCLUDING FIRE
WEATHER ZONES AZZ150-151...NORTHERN PORTIONS OF 152....AND
SOUTHERN PORTIONS OF 153.
&&
$$
VISIT US ON FACEBOOK...TWITTER...YOUTUBE...AND AT WEATHER.GOV/TUCSON
MEYER/RASMUSSEN
AREA FORECAST DISCUSSION
NWS DENVER/BOULDER CO
755 PM MDT WED APR 15 2015
.UPDATE...
ISSUED AT 749 PM MDT WED APR 15 2015
LOOKING THE AT WRF FM THIS AFTN...LOOKS LIKE ENOUGH INSTABILITY
WILL BE AROUND TO PRODUCE MORE THUNDERSTORMS OVER THE NORTHEAST
PLAINS...MAINLY EAST OF A LINE FROM STERLING TO CASTLE ROCK SO
ADDED A SLGT CHC OF THUNDERSTORMS TO THOSE AREAS THURSDAY AFTN.
SEE FIRE WEATHER DISCUSSION BELOW.
UPDATE ISSUED AT 628 PM MDT WED APR 15 2015
HAVE UPDATED TO BACK OFF THE POPS ESPECIALLY OVER THE SRN HALF OF
THE CWFA THIS EVENING. THE RUC AND THE HRRR SHIFT MUCH OF THE
PCPN NORTH OF THE CWFA THIS EVENING THEN BRING IT BACK TOWARDS 12Z
THURSDAY MORNING. HAVE ALSO INCREASED THE WINDS OVER THE NORTHEAST
PLAINS THIS EVENING.
&&
.SHORT TERM...(THIS AFTERNOON THROUGH THURSDAY)
ISSUED AT 238 PM MDT WED APR 15 2015
A SURFACE LOW OVER NORTHEAST COLORADO WILL MOVE EASTWARD OVERNIGHT
PULLING A COLD FRONT THROUGH EASTERN COLORADO THIS EVENING. LOW
LEVEL MOISTURE WILL INCREASE BEHIND IT. EXPECT SOME SHOWERS AND
PERHAPS A FEW THUNDERSTORMS TO FORM. BEST LIFT IS CURRENTLY OVER
LARIMER COUNTY AND INTO WYOMING AND WILL SHIFT NORTH THIS EVENING.
THEREFORE WILL KEEP POPS MAINLY IN TO 20 TO 60 PERCENT RANGE. THE
LOWER POPS WILL BE OVER LINCOLN COUNTY WHERE DRY AIR RESIDES NOW.
OVER THE NORTHEAST CORNER OF THE STATE...THERE MAY BE ENOUGH SHEAR
AND INSTABILITY TO PRODUCE A BRIEF SEVERE THUNDERSTORM.
EXPECT SHOWERS TO DECREASE LATE THIS EVENING AS SUBSIDENCE MOVES
OVER NORTHEAST COLORADO. STILL PLENTY OF MOISTURE IN PLACE BEHIND
THE FRONT...THUS WILL KEEP LOW CHANCES IN THE FORECAST THROUGH THE
NIGHT. ACTIVITY IS EXPECTED TO INCREASE THURSDAY MORNING AS UPPER
LEVEL LOW REACHES THE FOUR CORNERS AND AN EASTERLY UPSLOPE FLOW
INCREASES. BY LATE AFTERNOON EASTERLY UPSLOPE WINDS UP TO 30 KNOTS
WILL PREVAIL. THIS COMBINED WITH THE LIFT FROM THE LOW IS EXPECTED
TO PRODUCE WIDESPREAD RAIN AND SNOW BY LATE AFTERNOON. WITH THIS
SYSTEM LOOKING MORE CERTAIN WITH A GOOD CHANCE FOR HEAVY
SNOW...UPGRADED THE WINTER STORM WATCH TO A WARNING. WITH SNOW
EXPECTED TO BEGIN THURSDAY AFTERNOON MOVED UP THE TIME OF THE
WATCH.
.LONG TERM...(THURSDAY NIGHT THROUGH TUESDAY)
ISSUED AT 238 PM MDT WED APR 15 2015
MODELS STILL SHOW DECENT AGREEMENT WITH UPPER LEVEL CLOSED LOW
OVER THE FOUR CORNERS REGION THURSDAY NIGHT UNTIL ABOUT 12Z ON
FRIDAY. DYNAMICS ARE PROMISING WITH FAVORABLE MID LEVEL LAPSE
RATES AND QG BETWEEN -30 AND -35 MB/HR AT BOTH THE 500 AND 700 MB
LEVELS. SURFACE LOW WILL STRENGTHEN OVER THE EASTERN PORTION OF
THE STATE INCREASING MOISTURE ALONG THE FOOTHILLS WITH ONGOING
UPSLOPE EASTERLY FLOW THROUGH 00Z SATURDAY. THIS WILL HELP TO KEEP
PRECIPITATION OVER THE REGION THROUGH THE DAY FRIDAY. THE BIG
QUESTION STILL REMAINS ON WHERE THE SNOW WILL FALL VS RAIN/SNOW VS
RAIN. CURRENTLY MODELS ARE STILL INDICATING A RAIN AND SNOW
MIXTURE OVER MUCH OF THE FRONT RANGE URBAN CORRIDOR AND OUT TO DIA
WITH PREDOMINATELY RAIN FURTHER EAST OVER THE PLAINS. WITH PROFILE
TEMPERATURES COOLING CLOSER TO THE FOOTHILLS SNOW WILL DOMINATE
WITH INCREASING FROZEN PRECIPITATION ACCUMULATION ALONG THE
FOOTHILLS...MOUNTAINS AND PALMER DIVIDE AREA. WE COULD SEE
RAIN/SNOW TURNING MORE TO SNOW FRIDAY MORNING AS THE ATMOSPHERE
COOLS...INCREASING SNOWFALL AMOUNTS OVER DENVER INTO THE 1-4 INCH
RANGE. IF A BATCH OF COOLER AIR DOES MAKE ITS WAY INTO THE REGION
SNOW FALL AMOUNTS COULD GO UP FROM THESE VALUES.
FRIDAY NIGHT INTO SATURDAY THERE IS STILL SOME CONTENTION AMONGST
THE MODELS IN REGARDS TO THE UPPER LOWS PATH. THE 12Z GFS BRINGS
THE UPPER LOW CENTER NORTH TOWARD THE WY BORDER. THE NAM AND 00Z
EC KEEPS THE LOW CENTERED MORE SOUTH OVER THE SOUTHERN CO AND NM
BORDER. THE LATTER SET UP WILL ALLOW FOR PRECIPITATION TO LINGER
OVER THE PLAINS THROUGH SATURDAY WITH THE FORMER GFS ROUTE TO END
IT EARLIER SATURDAY MORNING. TEMPERATURES ON FRIDAY WILL BE COOL
OVERNIGHT WITH LOWS AROUND FREEZING AND HIGH TEMPERATURES IN THE
LOWER 50S WITH 20S AND 30S FOR THE MOUNTAINS.
PRECIPITATION WILL REMAIN A THREAT IN THE FOOTHILLS AND MOUNTAINS
THROUGH FRIDAY WITH OVER A FOOT POSSIBLE AND UP TO 2 FEET IN SOME
AREAS. WILL MAINTAIN CURRENT WATCH BUT WILL LOOK AT STARTING A BIT
EARLIER...POSSIBLY BY THURSDAY AFTERNOON AS MODELS INDICATE
SIGNIFICANT PRECIPITATION BY THIS TIME. MODELS ARE STILL
INDICATING INCREASED QPF AMOUNTS OF UP TO 2 INCHES OVER THE PLAINS
WITH SOME AREAS CLOSER TO THE FOOTHILLS RECEIVING UP TO 3
INCHES...MOST LIKELY A MIXTURE OF RAIN AND VERY WET SNOW.
BY SATURDAY NIGHT INTO SUNDAY THE UPPER LEVEL LOW IS PROGGED TO
MOVE OFF TO THE EAST OF THE REGION. THERE IS LITTLE RELIEF AS A
SECONDARY PUSH OF COOLER AIR MOVES INTO NORTHERN CO FROM THE NW.
EC HAS FAVORABLE QG ASCENT FOR SUNDAY WITH INCREASED MOISTURE IN
THE MORNING. WITH THE MOISTURE AND DYNAMICS IT WILL BE POSSIBLE TO
SEE ANOTHER ROUND OF PRECIPITATION ON SUNDAY. 700MB MODEL TEMPS
INDICATE A POSSIBLE CHANCE OF SNOW BY THE AFTERNOON WITH THE
AIRMASS COOLING IN THE LOWER LEVELS. TEMPERATURES ON SUNDAY WILL
BE IN THE UPPER 40S TO LOWER 50S WITH OVERNIGHT TEMPS AROUND
FREEZING ONCE AGAIN FOR THE DENVER AREA.
SUNDAY NIGHT INTO MONDAY ANOTHER DISTURBANCE IN THE UPPER LEVEL
FLOW WILL CONTINUE TO KEEP NE CO UNDER A SLIGHT CHANCE OF
PRECIPITATION WITH ANOTHER FRONT. HIGH TEMPERATURES WILL REMAIN IN
THE LOWER 50S. ON TUESDAY THE PATTERN WILL STAY ACTIVE WITH
ANOTHER DISTURBANCE MOVING THROUGH IN NORTHWESTERLY FLOW ALOFT.
THE MODELS DIVERGE THIS LATE IN THE FORECAST PERIOD SO WILL KEEP
POPS MODEST UNTIL LATER MODEL RUNS.
&&
.AVIATION...(FOR THE TAFS THROUGH 06Z THURSDAY EVENING)
ISSUED AT 628 PM MDT WED APR 15 2015
CEILINGS WILL LOWER TO 3000 TO 6000 FEET LATER THIS EVENING
BEHIND A COLD FRONT. GUSTS OF 30-35 KTS STILL POSSIBLE OVER THE
NEXT HOUR OR SO THEN THEY SHOULD DECREASE. NORTHERLY WINDS ARE
EXPECTED TO CONTINUE THROUGH TONIGHT AND INTO THURSDAY. WITH THE
STORM SYSTEM APPROACHING...EXPECT CEILINGS TO REMAIN BELOW 3000
FEET LATE TONIGHT AND THURSDAY. CEILINGS BELOW 1000 FEET WILL BE
POSSIBLE THURSDAY. BEST CHANCE FOR SHOWERS WILL BE LATE TONIGHT
AFTER 09Z...WITH SNOW IN THE 12-15Z TIME FRAME THURSDAY MORNING.
NO SNOW ACCUMULATION IS EXPECTED. RAIN IS EXPECTED TO BECOME
PERSISTENT LATE THURSDAY MORNING OR EARLY AFTERNOON. RIGHT NOW
LOOKS TOO WARM FOR SNOW THURSDAY AFTERNOON. HOWEVER SNOW WILL BE
POSSIBLE THURSDAY NIGHT AND FRIDAY WITH UP TO 6 INCHES POSSIBLE AT
KAPA AND KBJC...LIGHTER AMOUNTS ARE EXPECTED AT KDEN.
&&
.FIRE WEATHER...
ISSUED AT 749 PM MDT WED APR 15 2015
ALTHOUGH THE AMS OVER SOUTHERN LINCOLN COUNTY IS STILL QUITE DRY
...IT WILL CHANGE QUICKLY WITH THE PASSAGE OF THE COLD FRONT. THE
FRONT WILL BE MOVING THROUGH THE AREA IN THE NEXT HOUR OR SO.
DEWPOINTS IN THE LOWER 30S BEHIND THE FRONT ALLOWED THE RELATIVE
HUMIDITIES TO JUMP FOR THE SINGLE DIGITS AT LIMON AND HUGO...TO
AROUND 50 PERCENT IN 15 MINUTES. WITH THIS IN MIND...WL ALLOW THE
RED FLAG WARNING FOR FIRE WEATHER ZONE 247 TO EXPIRE AT 8 PM MDT.
&&
.BOU WATCHES/WARNINGS/ADVISORIES...
WINTER STORM WARNING FROM NOON THURSDAY TO 6 AM MDT SATURDAY FOR
COZ033>036.
&&
$$
UPDATE...COOPER
SHORT TERM...MEIER
LONG TERM...BOWEN
AVIATION...COOPER/MEIER
FIRE WEATHER...COOPER
AREA FORECAST DISCUSSION
NWS DENVER/BOULDER CO
632 PM MDT WED APR 15 2015
.UPDATE...
ISSUED AT 628 PM MDT WED APR 15 2015
HAVE UPDATED TO BACK OFF THE POPS ESPECIALLY OVER THE SRN HALF OF
THE CWFA THIS EVENING. THE RUC AND THE HRRR SHIFT MUCH OF THE
PCPN NORTH OF THE CWFA THIS EVENING THEN BRING IT BACK TOWARDS 12Z
THURSDAY MORNING. HAVE ALSO INCREASED THE WINDS OVER THE NORTHEAST
PLAINS THIS EVENING.
&&
.SHORT TERM...(THIS AFTERNOON THROUGH THURSDAY)
ISSUED AT 238 PM MDT WED APR 15 2015
A SURFACE LOW OVER NORTHEAST COLORADO WILL MOVE EASTWARD OVERNIGHT
PULLING A COLD FRONT THROUGH EASTERN COLORADO THIS EVENING. LOW
LEVEL MOISTURE WILL INCREASE BEHIND IT. EXPECT SOME SHOWERS AND
PERHAPS A FEW THUNDERSTORMS TO FORM. BEST LIFT IS CURRENTLY OVER
LARIMER COUNTY AND INTO WYOMING AND WILL SHIFT NORTH THIS EVENING.
THEREFORE WILL KEEP POPS MAINLY IN TO 20 TO 60 PERCENT RANGE. THE
LOWER POPS WILL BE OVER LINCOLN COUNTY WHERE DRY AIR RESIDES NOW.
OVER THE NORTHEAST CORNER OF THE STATE...THERE MAY BE ENOUGH SHEAR
AND INSTABILITY TO PRODUCE A BRIEF SEVERE THUNDERSTORM.
EXPECT SHOWERS TO DECREASE LATE THIS EVENING AS SUBSIDENCE MOVES
OVER NORTHEAST COLORADO. STILL PLENTY OF MOISTURE IN PLACE BEHIND
THE FRONT...THUS WILL KEEP LOW CHANCES IN THE FORECAST THROUGH THE
NIGHT. ACTIVITY IS EXPECTED TO INCREASE THURSDAY MORNING AS UPPER
LEVEL LOW REACHES THE FOUR CORNERS AND AN EASTERLY UPSLOPE FLOW
INCREASES. BY LATE AFTERNOON EASTERLY UPSLOPE WINDS UP TO 30 KNOTS
WILL PREVAIL. THIS COMBINED WITH THE LIFT FROM THE LOW IS EXPECTED
TO PRODUCE WIDESPREAD RAIN AND SNOW BY LATE AFTERNOON. WITH THIS
SYSTEM LOOKING MORE CERTAIN WITH A GOOD CHANCE FOR HEAVY
SNOW...UPGRADED THE WINTER STORM WATCH TO A WARNING. WITH SNOW
EXPECTED TO BEGIN THURSDAY AFTERNOON MOVED UP THE TIME OF THE
WATCH.
.LONG TERM...(THURSDAY NIGHT THROUGH TUESDAY)
ISSUED AT 238 PM MDT WED APR 15 2015
MODELS STILL SHOW DECENT AGREEMENT WITH UPPER LEVEL CLOSED LOW
OVER THE FOUR CORNERS REGION THURSDAY NIGHT UNTIL ABOUT 12Z ON
FRIDAY. DYNAMICS ARE PROMISING WITH FAVORABLE MID LEVEL LAPSE
RATES AND QG BETWEEN -30 AND -35 MB/HR AT BOTH THE 500 AND 700 MB
LEVELS. SURFACE LOW WILL STRENGTHEN OVER THE EASTERN PORTION OF
THE STATE INCREASING MOISTURE ALONG THE FOOTHILLS WITH ONGOING
UPSLOPE EASTERLY FLOW THROUGH 00Z SATURDAY. THIS WILL HELP TO KEEP
PRECIPITATION OVER THE REGION THROUGH THE DAY FRIDAY. THE BIG
QUESTION STILL REMAINS ON WHERE THE SNOW WILL FALL VS RAIN/SNOW VS
RAIN. CURRENTLY MODELS ARE STILL INDICATING A RAIN AND SNOW
MIXTURE OVER MUCH OF THE FRONT RANGE URBAN CORRIDOR AND OUT TO DIA
WITH PREDOMINATELY RAIN FURTHER EAST OVER THE PLAINS. WITH PROFILE
TEMPERATURES COOLING CLOSER TO THE FOOTHILLS SNOW WILL DOMINATE
WITH INCREASING FROZEN PRECIPITATION ACCUMULATION ALONG THE
FOOTHILLS...MOUNTAINS AND PALMER DIVIDE AREA. WE COULD SEE
RAIN/SNOW TURNING MORE TO SNOW FRIDAY MORNING AS THE ATMOSPHERE
COOLS...INCREASING SNOWFALL AMOUNTS OVER DENVER INTO THE 1-4 INCH
RANGE. IF A BATCH OF COOLER AIR DOES MAKE ITS WAY INTO THE REGION
SNOW FALL AMOUNTS COULD GO UP FROM THESE VALUES.
FRIDAY NIGHT INTO SATURDAY THERE IS STILL SOME CONTENTION AMONGST
THE MODELS IN REGARDS TO THE UPPER LOWS PATH. THE 12Z GFS BRINGS
THE UPPER LOW CENTER NORTH TOWARD THE WY BORDER. THE NAM AND 00Z
EC KEEPS THE LOW CENTERED MORE SOUTH OVER THE SOUTHERN CO AND NM
BORDER. THE LATTER SET UP WILL ALLOW FOR PRECIPITATION TO LINGER
OVER THE PLAINS THROUGH SATURDAY WITH THE FORMER GFS ROUTE TO END
IT EARLIER SATURDAY MORNING. TEMPERATURES ON FRIDAY WILL BE COOL
OVERNIGHT WITH LOWS AROUND FREEZING AND HIGH TEMPERATURES IN THE
LOWER 50S WITH 20S AND 30S FOR THE MOUNTAINS.
PRECIPITATION WILL REMAIN A THREAT IN THE FOOTHILLS AND MOUNTAINS
THROUGH FRIDAY WITH OVER A FOOT POSSIBLE AND UP TO 2 FEET IN SOME
AREAS. WILL MAINTAIN CURRENT WATCH BUT WILL LOOK AT STARTING A BIT
EARLIER...POSSIBLY BY THURSDAY AFTERNOON AS MODELS INDICATE
SIGNIFICANT PRECIPITATION BY THIS TIME. MODELS ARE STILL
INDICATING INCREASED QPF AMOUNTS OF UP TO 2 INCHES OVER THE PLAINS
WITH SOME AREAS CLOSER TO THE FOOTHILLS RECEIVING UP TO 3
INCHES...MOST LIKELY A MIXTURE OF RAIN AND VERY WET SNOW.
BY SATURDAY NIGHT INTO SUNDAY THE UPPER LEVEL LOW IS PROGGED TO
MOVE OFF TO THE EAST OF THE REGION. THERE IS LITTLE RELIEF AS A
SECONDARY PUSH OF COOLER AIR MOVES INTO NORTHERN CO FROM THE NW.
EC HAS FAVORABLE QG ASCENT FOR SUNDAY WITH INCREASED MOISTURE IN
THE MORNING. WITH THE MOISTURE AND DYNAMICS IT WILL BE POSSIBLE TO
SEE ANOTHER ROUND OF PRECIPITATION ON SUNDAY. 700MB MODEL TEMPS
INDICATE A POSSIBLE CHANCE OF SNOW BY THE AFTERNOON WITH THE
AIRMASS COOLING IN THE LOWER LEVELS. TEMPERATURES ON SUNDAY WILL
BE IN THE UPPER 40S TO LOWER 50S WITH OVERNIGHT TEMPS AROUND
FREEZING ONCE AGAIN FOR THE DENVER AREA.
SUNDAY NIGHT INTO MONDAY ANOTHER DISTURBANCE IN THE UPPER LEVEL
FLOW WILL CONTINUE TO KEEP NE CO UNDER A SLIGHT CHANCE OF
PRECIPITATION WITH ANOTHER FRONT. HIGH TEMPERATURES WILL REMAIN IN
THE LOWER 50S. ON TUESDAY THE PATTERN WILL STAY ACTIVE WITH
ANOTHER DISTURBANCE MOVING THROUGH IN NORTHWESTERLY FLOW ALOFT.
THE MODELS DIVERGE THIS LATE IN THE FORECAST PERIOD SO WILL KEEP
POPS MODEST UNTIL LATER MODEL RUNS.
&&
.AVIATION...(FOR THE TAFS THROUGH 06Z THURSDAY EVENING)
ISSUED AT 628 PM MDT WED APR 15 2015
CEILINGS WILL LOWER TO 3000 TO 6000 FEET LATER THIS EVENING
BEHIND A COLD FRONT. GUSTS OF 30-35 KTS STILL POSSIBLE OVER THE
NEXT HOUR OR SO THEN THEY SHOULD DECREASE. NORTHERLY WINDS ARE
EXPECTED TO CONTINUE THROUGH TONIGHT AND INTO THURSDAY. WITH THE
STORM SYSTEM APPROACHING...EXPECT CEILINGS TO REMAIN BELOW 3000
FEET LATE TONIGHT AND THURSDAY. CEILINGS BELOW 1000 FEET WILL BE
POSSIBLE THURSDAY. BEST CHANCE FOR SHOWERS WILL BE LATE TONIGHT
AFTER 09Z...WITH SNOW IN THE 12-15Z TIME FRAME THURSDAY MORNING.
NO SNOW ACCUMULATION IS EXPECTED. RAIN IS EXPECTED TO BECOME
PERSISTENT LATE THURSDAY MORNING OR EARLY AFTERNOON. RIGHT NOW
LOOKS TOO WARM FOR SNOW THURSDAY AFTERNOON. HOWEVER SNOW WILL BE
POSSIBLE THURSDAY NIGHT AND FRIDAY WITH UP TO 6 INCHES POSSIBLE AT
KAPA AND KBJC...LIGHTER AMOUNTS ARE EXPECTED AT KDEN.
&&
.FIRE WEATHER...
ISSUED AT 628 PM MDT WED APR 15 2015
STRONG WIND GUSTS AHEAD OF AND FOLLOWING THE PASSAGE OF A COLD
FRONT LATE THIS AFTERNOON AND EVENING HAVE DROPPED THE RH VALUES
INTO THE SINGLE DIGITS OVER LINCOLN COUNTY. GUSTY WINDS WILL
PERSIST THROUGH THE EVENING WITH A SLOW RECOVERY IN THE RH VALUES
THIS EVENING. WL CONTINUE WITH THE RED FLAG WARNING FOR FIRE
WEATHER ZONE 247 UNTIL 8 PM MDT THIS EVENING.
&&
.BOU WATCHES/WARNINGS/ADVISORIES...
RED FLAG WARNING UNTIL 8 PM MDT THIS EVENING FOR COZ247.
WINTER STORM WARNING FROM NOON THURSDAY TO 6 AM MDT SATURDAY FOR
COZ033>036.
&&
$$
UPDATE...COOPER
SHORT TERM...MEIER
LONG TERM...BOWEN
AVIATION...COOPER/MEIER
FIRE WEATHER...COOPER
AREA FORECAST DISCUSSION
NWS GRAND JUNCTION CO
ISSUED BY NATIONAL WEATHER SERVICE SALT LAKE CITY UT
452 PM MDT TUE APR 14 2015
.SHORT TERM...(THIS EVENING THROUGH WEDNESDAY NIGHT)
ISSUED AT 411 PM MDT TUE APR 14 2015
THE APPROACHING UPPER TROUGH IS CURRENTLY CENTERED OVER EASTERN
NEVADA PER LATEST WATER VAPOR IMAGERY AND RAP ANALYSIS WITH
ASSOCIATED COLD FRONT HAVING ALREADY CROSSED THE NORTHWESTERN
QUADRANT OF UTAH. THE FRONT IS EXPECTED TO REACH NORTHEAST AND
EAST-CENTRAL UTAH BY 00Z...THEN CROSS INTO WESTERN COLORADO DURING
THE EVENING HOURS. STRONG WINDS HAVE MATERIALIZED OVER THE
FORECAST AREA...ESPECIALLY UTAH AND NORTHWEST COLORADO ZONES WITH
MANY REPORTS OF GUSTS OVER 40 MPH. WINDS SHOULD CONTINUE TO
INCREASE THROUGH THE REMAINDER OF THE AFTERNOON AND INTO THE
EVENING HOURS...REMAINING GUSTY ON BOTH SIDES OF THE COLD FRONT.
GOING WIND HIGHLIGHTS LOOK GOOD AND WILL CONTINUE THROUGH LATE
TONIGHT.
SOME CUMULUS BLOWUPS ARE CURRENTLY SEEN ON SATELLITE ALTHOUGH NOT
MUCH IN THE WAY OF SHOWERS ARE EVIDENT AS OF YET. SOME PREFRONTAL
SHOWERS ARE STILL POSSIBLE THROUGH THIS EVENING BUT EXPECT
PRECIPITATION TO FILL IN MORE BEHIND THE FRONT. SNOW LEVELS WILL
LOWER QUICKLY WITH HIGHER VALLEYS STARTING TO SEE A THREAT OF
SNOW LATE TONIGHT.
HOWEVER...THE TROUGH IS EXPECTED TO PINCH OFF INTO A CLOSED LOW
TONIGHT WHICH WILL SLOW ITS EASTWARD PROGRESSION AND WEAKEN THE
FRONT AS IT CONTINUES THROUGH THE EASTERN PORTIONS OF THE FORECAST
AREA. AS SUCH...PRECIPITATION AMOUNTS/RATES ARE NOT EXPECTED TO BE
VERY SIGNIFICANT. THE LOW CENTER WILL REMAIN NEAR THE
UTAH/COLORADO BORDER TOMORROW BEFORE SETTLING OVER THE FOUR
CORNERS AREA BY TOMORROW NIGHT. THIS WILL KEEP UNSETTLED WEATHER
OVER THE AREA TOMORROW.
WITH MUCH COLDER AIR FILTERING BEHIND THE FRONT...EXPECT MAX
TEMPERATURES TOMORROW 25-30 DEGREES COOLER ACROSS MANY AREAS. THIS
COOLER AIR WILL ALSO BRING A POTENTIAL FOR FREEZING TEMPERATURES
TOMORROW NIGHT. A FREEZE WATCH REMAINS IN EFFECT AS A RESULT.
.LONG TERM...(THURSDAY THROUGH TUESDAY)
ISSUED AT 411 PM MDT TUE APR 14 2015
THE OPERATIONAL GFS IS MORE PROGRESSIVE THAN THE ECMWF/GEM
SOLUTION REGARDING THE CLOSED LOW...WITH CONSIDERABLE SPREAD AMONG
THE GFS ENSEMBLES. HAVE SIDED MORE IN LINE WITH THE EC/GEM WHICH
KEEPS THE LOW IN THE VICINITY OF THE FOUR CORNERS THROUGH FRIDAY.
ALTHOUGH THE AIRMASS GRADUALLY TRENDS WARMER DURING THIS
TIME...MOIST AND SOMEWHAT UNSTABLE CONDITIONS WILL KEEP A THREAT
OF SHOWERS ACROSS THE AREA...MOSTLY ACROSS THE HIGHER TERRAIN.
PRECIPITATION IS NOT EXPECTED TO BE VERY HEAVY DUE TO
EAST/NORTHEAST FLOW BUT LONG DURATION OF THE EVENT COULD LEAD TO
SEVERAL INCHES LOCALLY. MOUNTAINS FARTHER SOUTH SUCH AS THE SAN
JUANS WILL BE CLOSER TO THE LOW AND RESULTING WEAKER FLOW COULD
ALLOW FOR BETTER ACCUMULATIONS.
THE LOW WILL FINALLY EXIT THE AREA OVER THE WEEKEND AND YIELD TO A
SLIGHTLY CYCLONIC NORTHWEST FLOW ALOFT. A GRADUAL WARMING TREND
WILL TAKE PLACE DURING THIS TIME AND INTO THE EARLY PART OF NEXT
WEEK. HOWEVER...MODELS CONTINUE TO GENERATE A FEW SHOWERS OVER
THE HIGH TERRAIN WITH WEAK RIPPLES EMBEDDED IN THE FLOW.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z WEDNESDAY EVENING)
ISSUED AT 411 PM MDT TUE APR 14 2015
WEST TO SOUTHWEST WINDS HAVE INCREASED THIS AFTERNOON AHEAD OF AN
APPROACHING COLD FRONT...WITH GUSTS OF 25-35 KTS WIDESPREAD ACROSS
THE FORECAST AREA. SOME ADDITIONAL INCREASE IN WINDS IS EXPECTED
DURING THE EARLY EVENING BEFORE THE FRONT PASSES THROUGH DURING
THE VERY LATE EVENING/EARLY MORNING HOURS. THE FRONT WILL CAUSE
WINDS TO ABRUPTLY SHIFT TO THE NORTH/NORTHWEST...WITH STRONG GUSTS
CONTINUING FOR A FEW HOURS BEHIND THE FRONT.
PRECIPITATION BEHIND THE FRONT IS EXPECTED TO BE SCATTERED IN
NATURE...BECOMING ALL SNOW AT HIGHER ELEVATIONS. PERIODS OF IFR
CONDITIONS CANNOT BE RULED OUT WITH ANY SHOWERS THAT MOVE OVER THE
TAF SITES.
&&
.FIRE WEATHER...
ISSUED AT 411 PM MDT TUE APR 14 2015
A RED FLAG WARNING HAS BEEN ISSUED THROUGH 9PM
FOR ALL WESTERN COLORADO ZONES BELOW 8000 FEET.
A STRONG COLD FRONT WILL APPROACH THE AREA OVERNIGHT INTO WEDNESDAY
MORNING. THIS WILL CONTINUE TO BRING STRONG WINDS TO MUCH OF THE
AREA...WITH WIND GUSTS UP TO 65 MPH POSSIBLE. THIS COLD FRONT WILL
REACH NORTHEASTERN UTAH LATER THIS EVENING...ARRIVING ACROSS SOUTH
CENTRAL COLORADO BY WEDNESDAY MORNING. EXPECT A SUBSTANTIAL DROP IN
TEMPERATURES WILL THIS FRONT ALONG WITH ISOLATED TO WIDELY SCATTERED
SHOWERS AND THUNDERSTORMS ACROSS THE HIGHER TERRAIN. COOLER AND
UNSETTLED WEATHER REMAIN IN PLACE THROUGH THE END OF THE WEEK.
&&
.GJT WATCHES/WARNINGS/ADVISORIES...
CO...WIND ADVISORY UNTIL 3 AM MDT WEDNESDAY FOR COZ002-003-006>008-
011-020-021.
HIGH WIND WARNING UNTIL 3 AM MDT WEDNESDAY FOR COZ001-006.
FREEZE WATCH FROM LATE WEDNESDAY NIGHT THROUGH THURSDAY MORNING
FOR COZ001-006-011.
RED FLAG WARNING UNTIL 9 PM MDT THIS EVENING FOR COZ200>203-205-
207-290-292.
UT...WIND ADVISORY UNTIL 3 AM MDT WEDNESDAY FOR UTZ023-025-028.
HIGH WIND WARNING UNTIL 3 AM MDT WEDNESDAY FOR UTZ022-024-027-
029.
FREEZE WATCH FROM LATE WEDNESDAY NIGHT THROUGH THURSDAY MORNING
FOR UTZ022-024-027-029.
&&
$$
SHORT TERM...LC
LONG TERM...LC
AVIATION...MT
FIRE WEATHER...CK
AREA FORECAST DISCUSSION
NWS NEW YORK NY
552 AM EDT TUE APR 14 2015
.SYNOPSIS...
A COLD FRONT WILL MOVE ACROSS THE AREA THIS MORNING...FOLLOWED BY
HIGH PRESSURE BUILDING INTO THE REGION THROUGH THURSDAY...MOVING
OFFSHORE THURSDAY NIGHT. A FRONTAL SYSTEM COULD BRING SOME RAIN
FOR PARTS OF THE WEEKEND AND INTO THE FIRST PART OF NEXT WEEK.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
FORECAST IS GENERALLY ON TRACK. MADE SOME MINOR ADJUSTMENTS TO
HOURLY T/TD/SKY AND POPS OVER THE NEXT 6 HOURS TO FIT BETTER WITH
CURRENT OBS AND RADAR TRENDS.
SHORTWAVE TROUGH PASSES TO THE N TODAY WITH A COLD FRONT TRACKING
ACROSS THE AREA THIS MORNING. WINDS HAVE JUST SHIFTED TO THE NW AT
KMGJ AS OF 930Z AND WILL CONTINUE TO TRACK SE REACHING NYC AROUND
12Z AND THEN ACROSS THE REST OF THE AREA THROUGH MID MORNING.
BAND OF SHOWERS ALONG AND BEHIND THE FRONT DOES NOT APPEAR TO BE
WEAKENING AS THE HRRR AND HI RES NAM HAS BEEN INDICATING...SO POPS
LOOK GOOD. THIS BAND WILL TRAVERSE THE REGION THROUGH AROUND 15Z.
DRY CONDS THEN RETURN ALTHOUGH HIGH CLOUDS WILL REMAIN OHD INTO
TONIGHT. HAVE KEPT A PTLY SUNNY FORECAST AS A RESULT ALTHOUGH THERE
IS SOME UNCERTAINTY IN THE OPACITY...AND COULD HAVE TO LOWER
CLOUDS COVER LATER TODAY...ESPECIALLY NRN ZONES. CLOSER TO THE
COAST...MOSTLY CLOUDY CONDS ARE EXPECTED WITH SHOWERS LINGERING
MAINLY OFFSHORE THROUGH THE DAY.
CAA IS VERY GRADUAL BEHIND THE FROPA...SO HIGHS ARE EXPECTED TO BE
IN THE LOWER TO MID 60S ACROSS THE LOCAL AREA.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM WEDNESDAY/...
A WAVE OF LOW PRES WILL DEVELOP ALONG THE FRONT LATE THIS AFTN/EVE
PASSING TO THE S TONIGHT. NO IMPACTS ARE EXPECTED FROM THIS. SKIES
WILL CLEAR TONIGHT WITH PERHAPS JUST SOME THIN CIRRUS FROM THE LOW
PASSING TO THE S. LIGHT NLY WINDS AND A MOSTLY CLEAR SKY WILL
ALLOW FOR GOOD RADIATIONAL COOLING CONDS WITH THE USUALLY COLDER
SPOTS DROPPING INTO THE 30S. THE GROWING SEASON EXPANDS TO INCLUDE
ALL OF LONG ISLAND...COASTAL CT...SRN PORTIONS OF THE LOWER HUDSON
VALLEY AND MOST OF NE NJ ON THE 15TH...ALTHOUGH DEWPOINT
DEPRESSIONS LOOK TO BE BETWEEN 15 AND 20 DEGREES. THEREFORE...NOT
EXPECTING ANY FROST DEVELOPMENT IN EASTERN LI AND SE COASTAL CT.
CANADIAN HIGH PRES BUILDS IN FOR WED WITH SUNNY SKIES AND HIGHS IN
THE MID TO UPPER 60S UNDER A NLY FLOW.
&&
.LONG TERM /WEDNESDAY NIGHT THROUGH MONDAY/...
HIGH PRESSURE WILL PROVIDE FAIR AND DRY CONDITIONS WEDNESDAY NIGHT
THROUGH THURSDAY NIGHT. THE HIGH WILL BUILD OFFSHORE THURSDAY NIGHT
AND FRIDAY.
A FRONTAL BOUNDARY WILL THEN SET UP NEAR THE REGION ON FRIDAY AND
REMAIN NEAR THE REGION THROUGH THE WEEKEND. SEVERAL WAVES OF LOW
PRESSURE TRAVELING ALONG THE FRONT WILL BRING PERIODS OF UNSETTLED
WEATHER TO THE REGION THROUGH THIS TIME PERIOD. ANY PRECIPITATION
THIS WEEKEND WILL BE ON AND OFF AND WILL LIMIT POPS TO CHANCE OR
SLIGHT CHANCE. THE UNSETTLED WEATHER COULD CONTINUE INTO MONDAY.
FOR TEMPERATURES...EXPECT HIGHS TO WARM A LITTLE BIT EACH DAY
THROUGH SATURDAY WITH HIGHS IN THE 50S AND LOWER 60S ON THURSDAY...
LOWER AND MIDDLE 60S ON FRIDAY AND MIDDLE 60S TO LOWER 70S ON
SATURDAY. HIGHS FALL BACK INTO THE UPPER 50S TO MIDDLE 60S SUNDAY
AND MONDAY.
&&
.AVIATION /10Z TUESDAY THROUGH SATURDAY/...
A COLD FRONT WILL REACH KSWF JUST BEFORE DAYBREAK...THE NYC METRO
AREA BY 12Z...AND THE LONG ISLAND/CT TERMINALS FROM 13Z-15Z.
POST-FRONTAL RAIN BAND OVER ERN PA IS HOLDING TOGETHER ATTM BUT IS
FCST TO WEAKEN...AT WORST IT SHOULD BRING BRIEF MVFR CIGS TO MOST
TERMINALS AFTER PASSAGE.
LOW STRATUS HAS DEVELOPED ALONG THE COAST A LITTLE SOONER THAN
EXPECTED...IMPACTING KISP WITH IFR CIGS AS OF 08Z AND ABOUT TO DO
THE SAME AT KGON BY 09Z-10Z. STILL A CHANCE OF IMPACT AT KJFK FROM
10Z-12Z THOUGH HAVE GONE TEMPO RATHER THAN PREVAILING.
WINDS WITH FROPA IN ERN PA ARE SHIFTING MORE SHARPLY NW AND
BRIEFLY GUSTING TO 20 KT...SO HAVE INDICATED THIS IN TAF.
MEDIUM TO HIGH CONFIDENCE WIND FCST THROUGH THIS MORNING...THEN
LOW CONFIDENCE THIS AFTERNOON. BANKING ON POST-FRONTAL WINDS
BECOMING WEAK ENOUGH TO ALLOW WEAK SEA BREEZES TO DEVELOP THIS
AFTERNOON...WITH EXACT TIMING OF ONSET UNCERTAIN. IF SEA BREEZES
DO NOT DEVELOP...WOULD INSTEAD EXPECT E-NE FLOW 5-8 KT FROM MID TO
LATE AFTERNOON.
NY METRO ENHANCED AVIATION WEATHER SUPPORT...
DETAILED INFORMATION...INCLUDING HOURLY TAF WIND COMPONENT FCSTS
CAN BE FOUND AT:
HTTP:/WWW.ERH.NOAA.GOV/ZNY/N90 (LOWER CASE)
KJFK FCSTER COMMENTS: LOW CONFIDENCE IN WIND DIRECTION
THIS AFTERNOON.
KLGA FCSTER COMMENTS: LOW CONFIDENCE IN WIND DIRECTION
THIS AFTERNOON.
KEWR FCSTER COMMENTS: LOW CONFIDENCE IN WIND DIRECTION
THIS AFTERNOON.
THE AFTERNOON KEWR HAZE POTENTIAL FORECAST IS GREEN...WHICH
IMPLIES SLANT RANGE VISIBILITY 7SM OR GREATER OUTSIDE OF CLOUD.
KTEB FCSTER COMMENTS: LOW CONFIDENCE IN WIND DIRECTION
THIS AFTERNOON.
KHPN FCSTER COMMENTS: LOW CONFIDENCE IN WIND DIRECTION
THIS AFTERNOON.
KISP FCSTER COMMENTS: LOW CONFIDENCE IN WIND DIRECTION
THIS AFTERNOON.
.OUTLOOK FOR 06Z WED THROUGH SAT...
.LATE TUE NIGHT-THU...VFR.
.THU NIGHT...MVFR CONDS POSSIBLE LATE AT NIGHT.
.FRI-SAT...MVFR CONDS POSSIBLE IN SHOWERS.
&&
.MARINE...
S-SW WINDS OF 15-20 KT AHEAD OF THE COLD FRONT EARLY THIS MORNING
IS EXPECTED TO BUILD SEAS TO MARGINAL SCA LEVELS ON THE OCEAN
WATERS. SEAS HAVE BEEN SLOW TO BUILD...AND MAY FALL JUST SHORT OF
5 FT...BUT DON`T HAVE HIGH ENOUGH CONFIDENCE THAT IT WON`T HAPPEN
TO TAKE IT DOWN. GUSTS SHOULD ONLY TOP OUT AROUND 20 KT DUE TO A
STRONG INVERSION OVER THE WATERS. LOW PRES PASSES S OF THE WATERS
TONIGHT WITH CANADIAN HIGH PRES BUILDING IN FOR WED. SUB-ADVSY
CONDS WILL PREVAIL THROUGH THIS TIME.
SUB SCA CONDITIONS ARE LIKELY WEDNESDAY NIGHT THROUGH FRIDAY NIGHT.
SMALL CRAFT ADVISORY CONDITIONS ARE LIKELY TO RETURN TO THE OCEAN
WATERS THIS WEEKEND.&&
.HYDROLOGY...
LESS THAN 1/4 OF AN INCH OF BASIN AVERAGE RAINFALL IS EXPECTED
THIS MORNING. MAINLY DRY WEATHER IS EXPECTED FROM THIS AFTERNOON-
THU NIGHT. THE NEXT CHANCE FOR MEASURABLE RAIN WILL BE FRIDAY AND
INTO THE WEEKEND.
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 WEB SITE.
&&
.OKX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...NONE.
NJ...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 11 AM EDT THIS MORNING FOR ANZ350-
353.
&&
$$
AREA FORECAST DISCUSSION
NWS NEW YORK NY
436 AM EDT TUE APR 14 2015
.SYNOPSIS...
A COLD FRONT WILL MOVE ACROSS THE AREA THIS MORNING...FOLLOWED BY
HIGH PRESSURE BUILDING INTO THE REGION THROUGH THURSDAY...MOVING
OFFSHORE THURSDAY NIGHT. A FRONTAL SYSTEM COULD BRING SOME RAIN
FOR PARTS OF THE WEEKEND AND INTO THE FIRST PART OF NEXT WEEK.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
SHORTWAVE TROUGH PASSES TO THE N TODAY WITH A COLD FRONT TRACKING
ACROSS THE AREA THIS MORNING. AT 07Z...COLD FRONT HAD JUST PASSED
THROUGH KMSV AND KABE WITH A BAND OF POST- FRONTAL SHOWERS JUST
BEHIND IT. THIS WILL TRAVERSE THE REGION FROM 09Z THROUGH AROUND
15Z...ALTHOUGH THE HI RES NAM AND HRRR TRENDS ARE INDICATING THE
SHOWERS BREAK UP AS THEY APPROACH NYC AND SOUTHERN CT AND THEN
REINVIGORATE S OF LONG ISLAND LATE THIS MORNING. AM HESITANT TO
LOWER POPS WITH A 50-60KT LLJ IN PLACE TO AID IN LIFT..ALTHOUGH
HAVE LOWERED QPF AMOUNTS TO 1-2 TENTHS.
HIGH CLOUDS WILL REMAIN OHD INTO TONIGHT...AND HAVE KEPT A PTLY
SUNNY FORECAST AS A RESULT. THERE IS SOME UNCERTAINTY IN THE
OPACITY OF IT...AND COULD HAVE TO LOWER CLOUDS COVER LATER
TODAY...ESPECIALLY NRN ZONES. CLOSER TO THE COAST...MOSTLY CLOUDY
CONDS ARE EXPECTED WITH SHOWERS LINGERING MAINLY OFFSHORE THROUGH
THE DAY.
CAA IS VERY GRADUAL BEHIND THE FROPA...SO HIGHS ARE EXPECTED TO BE
IN THE LOWER TO MID 60S ACROSS THE LOCAL AREA.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM WEDNESDAY/...
A WAVE OF LOW PRES WILL DEVELOP ALONG THE FRONT LATE THIS AFTN/EVE
PASSING TO THE S TONIGHT. NO IMPACTS ARE EXPECTED FROM THIS. SKIES
WILL CLEAR TONIGHT WITH PERHAPS JUST SOME THIN CIRRUS FROM THE LOW
PASSING TO THE S. LIGHT NLY WINDS AND A MOSTLY CLEAR SKY WILL
ALLOW FOR GOOD RADIATIONAL COOLING CONDS WITH THE USUALLY COLDER
SPOTS DROPPING INTO THE 30S. THE GROWING SEASON EXPANDS TO INCLUDE
ALL OF LONG ISLAND...COASTAL CT...SRN PORTIONS OF THE LOWER HUDSON
VALLEY AND MOST OF NE NJ ON THE 15TH...ALTHOUGH DEWPOINT
DEPRESSIONS LOOK TO BE BETWEEN 15 AND 20 DEGREES. THEREFORE...NOT
EXPECTING ANY FROST DEVELOPMENT IN EASTERN LI AND SE COASTAL CT.
CANADIAN HIGH PRES BUILDS IN FOR WED WITH SUNNY SKIES AND HIGHS IN
THE MID TO UPPER 60S UNDER A NLY FLOW.
&&
.LONG TERM /WEDNESDAY NIGHT THROUGH MONDAY/...
HIGH PRESSURE WILL PROVIDE FAIR AND DRY CONDITIONS WEDNESDAY NIGHT
THROUGH THURSDAY NIGHT. THE HIGH WILL BUILD OFFSHORE THURSDAY NIGHT
AND FRIDAY.
A FRONTAL BOUNDARY WILL THEN SET UP NEAR THE REGION ON FRIDAY AND
REMAIN NEAR THE REGION THROUGH THE WEEKEND. SEVERAL WAVES OF LOW
PRESSURE TRAVELING ALONG THE FRONT WILL BRING PERIODS OF UNSETTLED
WEATHER TO THE REGION THROUGH THIS TIME PERIOD. ANY PRECIPITATION
THIS WEEKEND WILL BE ON AND OFF AND WILL LIMIT POPS TO CHANCE OR
SLIGHT CHANCE. THE UNSETTLED WEATHER COULD CONTINUE INTO MONDAY.
FOR TEMPERATURES...EXPECT HIGHS TO WARM A LITTLE BIT EACH DAY
THROUGH SATURDAY WITH HIGHS IN THE 50S AND LOWER 60S ON THURSDAY...
LOWER AND MIDDLE 60S ON FRIDAY AND MIDDLE 60S TO LOWER 70S ON
SATURDAY. HIGHS FALL BACK INTO THE UPPER 50S TO MIDDLE 60S SUNDAY
AND MONDAY.
&&
.AVIATION /08Z TUESDAY THROUGH SATURDAY/...
A COLD FRONT WILL REACH KSWF JUST BEFORE DAYBREAK...THE NYC METRO
AREA BY 12Z...AND THE LONG ISLAND/CT TERMINALS FROM 13Z-15Z.
POST-FRONTAL RAIN BAND OVER ERN PA IS HOLDING TOGETHER ATTM BUT IS
FCST TO WEAKEN...AT WORST IT SHOULD BRING BRIEF MVFR CIGS TO MOST
TERMINALS AFTER PASSAGE.
LOW STRATUS HAS DEVELOPED ALONG THE COAST A LITTLE SOONER THAN
EXPECTED...IMPACTING KISP WITH IFR CIGS AS OF 08Z AND ABOUT TO DO
THE SAME AT KGON BY 09Z-10Z. STILL A CHANCE OF IMPACT AT KJFK FROM
10Z-12Z THOUGH HAVE GONE TEMPO RATHER THAN PREVAILING.
WINDS WITH FROPA IN ERN PA ARE SHIFTING MORE SHARPLY NW AND
BRIEFLY GUSTING TO 20 KT...SO HAVE INDICATED THIS IN TAF.
MEDIUM TO HIGH CONFIDENCE WIND FCST THROUGH THIS MORNING...THEN
LOW CONFIDENCE THIS AFTERNOON. BANKING ON POST-FRONTAL WINDS
BECOMING WEAK ENOUGH TO ALLOW WEAK SEA BREEZES TO DEVELOP THIS
AFTERNOON...WITH EXACT TIMING OF ONSET UNCERTAIN. IF SEA BREEZES
DO NOT DEVELOP...WOULD INSTEAD EXPECT E-NE FLOW 5-8 KT FROM MID TO
LATE AFTERNOON.
...NY METRO ENHANCED AVIATION WEATHER SUPPORT...
DETAILED INFORMATION...INCLUDING HOURLY TAF WIND COMPONENT FCSTS
CAN BE FOUND AT:
HTTP://WWW.ERH.NOAA.GOV/ZNY/N90 (LOWER CASE)
KJFK FCSTER COMMENTS: LOW CONFIDENCE IN WIND DIRECTION
THIS AFTERNOON.
KLGA FCSTER COMMENTS: LOW CONFIDENCE IN WIND DIRECTION
THIS AFTERNOON.
KEWR FCSTER COMMENTS: LOW CONFIDENCE IN WIND DIRECTION
THIS AFTERNOON.
THE AFTERNOON KEWR HAZE POTENTIAL FORECAST IS GREEN...WHICH
IMPLIES SLANT RANGE VISIBILITY 7SM OR GREATER OUTSIDE OF CLOUD.
KTEB FCSTER COMMENTS: LOW CONFIDENCE IN WIND DIRECTION
THIS AFTERNOON.
KHPN FCSTER COMMENTS: LOW CONFIDENCE IN WIND DIRECTION
THIS AFTERNOON.
KISP FCSTER COMMENTS: LOW CONFIDENCE IN WIND DIRECTION
THIS AFTERNOON.
.OUTLOOK FOR 06Z WED THROUGH SAT...
.LATE TUE NIGHT-THU...VFR.
.THU NIGHT...MVFR CONDS POSSIBLE LATE AT NIGHT.
.FRI-SAT...MVFR CONDS POSSIBLE IN SHOWERS.
&&
.MARINE...
S-SW WINDS OF 15-20 KT AHEAD OF THE COLD FRONT EARLY THIS MORNING
IS EXPECTED TO BUILD SEAS TO MARGINAL SCA LEVELS ON THE OCEAN
WATERS. SEAS HAVE BEEN SLOW TO BUILD...AND MAY FALL JUST SHORT OF
5 FT...BUT DON`T HAVE HIGH ENOUGH CONFIDENCE THAT IT WON`T HAPPEN
TO TAKE IT DOWN. GUSTS SHOULD ONLY TOP OUT AROUND 20 KT DUE TO A
STRONG INVERSION OVER THE WATERS. LOW PRES PASSES S OF THE WATERS
TONIGHT WITH CANADIAN HIGH PRES BUILDING IN FOR WED. SUB-ADVSY
CONDS WILL PREVAIL THROUGH THIS TIME.
SUB SCA CONDITIONS ARE LIKELY WEDNESDAY NIGHT THROUGH FRIDAY NIGHT.
SMALL CRAFT ADVISORY CONDITIONS ARE LIKELY TO RETURN TO THE OCEAN
WATERS THIS WEEKEND.&&
.HYDROLOGY...
LESS THAN 1/4 OF AN INCH OF BASIN AVERAGE RAINFALL IS EXPECTED
THIS MORNING. MAINLY DRY WEATHER IS EXPECTED FROM THIS AFTERNOON-
THU NIGHT. THE NEXT CHANCE FOR MEASURABLE RAIN WILL BE FRIDAY AND
INTO THE WEEKEND.
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 WEB SITE.
&&
.OKX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...NONE.
NJ...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 11 AM EDT THIS MORNING FOR ANZ350-
353.
&&
$$
AREA FORECAST DISCUSSION
NWS ALBANY NY
354 AM EDT TUE APR 14 2015
.SYNOPSIS...
A FAST MOVING COLD FRONT WILL BRING SHOWERS TO THE AREA THROUGH
EARLY THIS MORNING. DRY WEATHER WILL RETURN THIS AFTERNOON AND
PERSIST THROUGH THURSDAY. OUR NEXT CHANCES FOR SHOWERS WILL COME
LATE IN THE WEEK INTO THE FIRST PART OF THE WEEKEND.
&&
.NEAR TERM /UNTIL 6 PM THIS AFTERNOON/...
AS OF 350 AM EDT...REGIONAL MOSAIC RADAR IMAGERY CONTINUES TO
SHOW A BAND OF SHOWERS MOVING THROUGH THE REGION FROM SOUTHWEST TO
NORTHEAST. THESE SHOWERS ARE ALONG/AHEAD OF A FAST MOVING SFC COLD
FRONT AND UPPER LEVEL SHORTWAVE MOVING ACROSS EASTERN NY. THERE
MAY BE SOME ELEVATED CONVECTIVE ELEMENTS WITHIN THE SHOWERS. THE
LATEST 3KM HRRR SHOWS THESE ELEMENTS WEAKENING AS THEY MOVE
THROUGH OUR REGION...AS NOCTURNAL EFFECTS CONTINUE TO OCCUR AND
THE HEAVIER SHOWERS STARTS TO OUTRUN THEIR BEST SUPPORT ALOFT.
SHOWERS HAVE BEEN TRACKED SW TO NE...SO IT WILL TAKE A LITTLE
WHILE STILL FOR ACTIVITY TO REACH OUR ENTIRE AREA. WHILE SHOWERS
HAVE ALREADY ENDED ACROSS MOST OF THE WESTERN ADIRONDACKS AND
WESTERN MOHAWK VALLEY...IT WILL TAKE SOME TIME FOR THE SHOWERS TO
COMPLETELY CLEAR OUR FA WHICH WILL NOT OCCUR UNTIL LATER THIS
MORNING. TOTAL QPF FROM THE SHOWERS WILL GENERALLY BE A TENTH TO A
QUARTER OF AN INCH...WITH ISOLATED AMOUNTS UP TO A THIRD OF AN
INCH.
FOR THIS AFTERNOON EXPECT DRY CONDITIONS WITH MOSTLY SUNNY SKIES
NORTH AND MOSTLY CLOUDY SKIES SOUTH AS THERE WILL STILL BE A
CANOPY OF CIRRUS CLOUDS IN PLACE. IT WILL STILL BE BREEZY WITH
WEST WINDS 10 TO 20 MPH WITH GUSTS UP TO 35 MPH. HIGHS TODAY WILL
GENERALLY BE IN THE 60S WITH SOME UPPER 50S ACROSS PARTS OF THE
WESTERN ADIRONDACKS...TACONICS AND BERKSHIRES.
&&
.SHORT TERM /6 PM THIS AFTERNOON THROUGH THURSDAY NIGHT/...
CLEAR AND DRY WEATHER IS EXPECTED TONIGHT THROUGH MUCH OF
THURSDAY AS A LARGE RIDGE OF HIGH PRESSURE BUILDS EAST FROM THE
GREAT LAKES REGION TONIGHT ACROSS OUR REGION ON WEDNESDAY AND OFF
THE NEW ENGLAND COAST LATE WEDNESDAY NIGHT. EXPECT LOWS TONIGHT TO
BE IN THE UPPER 20S TO MID 30S WITH HIGHS ON WEDNESDAY IN THE
UPPER 50S TO UPPER 60S. LOWS WEDNESDAY NIGHT ARE EXPECTED TO RANGE
FROM THE UPPER TEENS NORTHWEST TO LOWER 30S SOUTHEAST WITH HIGHS
ON THURSDAY IN THE LOW TO MID 60S.
CLOUDS WILL BE INCREASING ACROSS THE REGION FROM WEST TO EAST LATE
THURSDAY WITH A CHANCE OF SHOWERS THURSDAY NIGHT ACROSS THE
NORTHWEST 3/4S OF THE FA AS A LOW PRESSURE SYSTEM STARTS TO LIFT
NORTHEAST FROM THE SOUTHEAST STATES AS A STATIONARY FRONT IS
DRAPED TO THE NORTH ACROSS SOUTHERN CANADA. LOWS THURSDAY NIGHT
WILL BE IN THE MID 30S TO MID 40S. THERE IS EVEN THE POSSIBILITY
OF A LITTLE SNOW ACROSS THE WESTERN ADIRONDACKS AND SOUTHERN GREEN
MOUNTAINS WITH LITTLE OR NO ACCUMULATION.
&&
.LONG TERM /FRIDAY THROUGH MONDAY/...
UNSETTLED WEATHER IS EXPECTED AT TIMES DURING THE EXTENDED
PERIOD...AS SEVERAL FAST MOVING STORM SYSTEMS EMBEDDED WITHIN THE
ZONAL FLOW IMPACT THE REGION.
FRIDAY...AN UPPER LEVEL DISTURBANCE WILL PASS ACROSS THE REGION.
THIS SYSTEM WILL BE FAIRLY WEAK AND THERE WON/T BE A TON OF MOISTURE
TO WORK WITH...BUT THERE IS A CHANCE FOR SOME LIGHT RAIN SHOWERS
ACROSS THE AREA...ALONG WITH PLENTY OF CLOUDS. TEMPS LOOK
SEASONABLE...WITH HIGHS IN THE MID 50S TO LOW 60S.
FRIDAY NIGHT...THERE MAY BE A LULL IN THE ACTION FOR FRIDAY NIGHT
INTO AT LEAST SATURDAY MORNING. HOWEVER...STILL CANNOT TOTALLY RULE
OUT A SHOWER SO WILL MAINTAIN SLIGHT CHC TO LOW CHC POPS FOR FRIDAY
NIGHT. WITH PLENTY OF LINGERING CLOUDS AROUND...LOW TEMPERATURES
SHOULD ONLY FALL INTO THE 40S FOR MOST AREAS.
SATURDAY-SATURDAY NIGHT...A MUCH STRONGER FRONTAL SYSTEM WILL BE
APPROACHING FOR SAT AFTN INTO SAT NIGHT. THERE WILL BE BETTER CHANCE
FOR RAIN SHOWERS WITH THIS SYSTEM...AS THERE WILL BE A STRONGER
THERMAL GRADIENT WITH THE SFC COLD FRONT AS COMPARED TO THE PREVIOUS
STORM SYSTEM. THERE ARE STILL TIMING DIFFERENCES WITHIN THE
MODELS...SO WON/T GO ANY HIGHER THAN CHC FOR POPS SAT AFTN THROUGH
SAT NIGHT UNTIL THE TIMING BECOMES MORE CERTAIN. TEMPS ON SAT LOOK
TO BE IN THE UPPER 50S TO UPPER 60S AHEAD OF THE APPROACHING FRONTAL
BOUNDARY...WARMEST ACROSS PORTIONS OF THE MID HUDSON VALLEY AND
SOUTHERN LITCHFIELD CO CT. SHOWERS SHOULD BE ENDING SOMETIME SAT
EVENING OR NIGHT. SAT NT/SUN AM LOWS SHOULD FALL INTO THE 30S TO
LOWER 40S.
SUNDAY-SUNDAY NIGHT...A BIT MORE UNCERTAINTY...AS THE 00Z/14 GFS AND
GEFS SUGGEST A SOUTHERN STREAM DISTURBANCE BRINGS CLOUDS AND SOME
SHOWERS TO THE REGION BY SUNDAY AFTERNOON...WHILE THE 00Z/14 ECMWF
AND GEM KEEP A TRANSIENT UPPER LEVEL RIDGE IN PLACE LONGER WITH DRY
WEATHER. SINCE PREVIOUS CYCLES OF THE GFS WERE NOT NEARLY AS
PESSIMISTIC...WILL KEEP THINGS GENERALLY DRY WITH THE EXCEPTION OF
SOME SLIGHT CHC/LOW CHC POPS FOR EXTREME SOUTHERN AREAS...MAINLY FOR
LATE IN THE DAY OR AT NIGHT. TEMPS WILL GENERALLY BE IN THE 50S TO
LOW 60S FOR HIGHS ON SUNDAY...WITH LOWS MAINLY IN THE 30S TO LOWER
40S FOR SUN NIGHT.
MON-TUE...THE NEXT STORM SYSTEM LOOKS TO IMPACT THE REGION AT SOME
POINT EARLY NEXT WEEK WITH ANOTHER SHOT OF RAIN SHOWERS. CURRENT
TIMING FAVORS BEST CHANCE FOR MON INTO EARLY MON NT...THEN POSSIBLY
TAPERING OFF BY TUE. WILL INDICATE CHC POPS FOR MON-MON NT...BEFORE
ONLY SLIGHT CHC FOR TUE. GIVEN THE CURRENT EXPECTATION FOR CLOUDS AND
SHOWERS FOR MON...WILL INDICATE SLIGHTLY BELOW NORMAL TEMPS...WITH
HIGHS MAINLY IN THE 50S AND LOWS MON NT/TUE AM IN THE 30S TO LOWER
40S. STILL COOL ON TUE...WITH HIGHS AGAIN MAINLY 55-60 IN VALLEYS
AND LOWER 50S ACROSS HIGHER ELEVATIONS.
&&
.AVIATION /08Z TUESDAY THROUGH SATURDAY/...
A COLD FRONT WILL MOVE EASTWARD ACROSS THE TAF SITES OVERNIGHT.
HIGH PRESSURE WILL BUILD IN FROM THE WEST FOR TUESDAY.
MAINLY VFR CONDITIONS ARE EXPECTED THROUGH AT LEAST 06Z/WED. A
BAND OF SHOWERS...MAINLY LIGHT IN INTENSITY...WILL MOVE EASTWARD
IN ASSOCIATION WITH THE COLD FRONTAL PASSAGE PRIOR TO DAYBREAK.
THE SHOWERS SHOULD BECOME MORE SPOTTY ONCE THEY REACH THE TAF
SITES. THE BEST CHANCE FOR SHOWERS SHOULD BE BETWEEN 06Z-
10Z/TUE...EXCEPT A BIT LATER...08Z-12Z/TUE AT KPSF AND KPOU. THERE
IS A SLIGHT CHANCE OF BRIEF MVFR CONDITIONS AS THE SHOWERS PASS
THROUGH...WITH THE GREATEST CHANCE AT KPSF.
OTHERWISE...ONLY HIGH CLOUDS ARE EXPECTED AT TIMES TUESDAY AND
TUESDAY NIGHT.
STRONG SOUTH WINDS WILL PERSIST AHEAD OF THE COLD FRONT...AT 10-15
KT...WITH SOME GUSTS OF 20-30 KT...STRONGEST AT KALB. WINDS WILL
SHIFT INTO THE WEST AS THE FRONT PASSES...AND MAY BRIEFLY GUST UP
TO 30 KT WITH THE INITIAL WIND SHIFT. OTHERWISE...WEST TO
NORTHWEST WINDS WILL AVERAGE 5-10 KT AROUND DAYBREAK
TUESDAY...THEN INCREASE TO 10-15 KT...WITH SOME GUSTS OF 20-25 KT
POSSIBLE AT KGFL/KALB AND KPSF. AT KPOU...WINDS SHOULD REMAIN
LIGHTER DURING TUE...AND BECOME NORTHWEST TO NORTH IN THE
AFTERNOON AT GENERALLY 5-10 KT. WINDS AT ALL TAF SITES SHOULD
REMAIN FROM THE WEST...AND DECREASE TO 5-10 KT SHORTLY AFTER
SUNSET TUESDAY.
OUTLOOK...
TUE NIGHT-THU: NO OPERATIONAL IMPACT. NO SIG WX.
THU NIGHT-FRI: MODERATE OPERATIONAL IMPACT. CHANCE OF SHRA.
FRI NIGHT: LOW OPERATIONAL IMPACT. SLIGHT CHANCE OF SHRA.
SAT: MODERATE OPERATIONAL IMPACT. CHANCE OF SHRA.
&&
.FIRE WEATHER...
...WEST WINDS MAY GUST AS HIGH AS 35 MPH THIS AFTERNOON
ESPECIALLY ACROSS THE HIGHER TERRAIN...
A FAST MOVING COLD FRONT WILL BRING SHOWERS TO THE AREA THROUGH
EARLY THIS MORNING. DRY WEATHER WILL RETURN THIS AFTERNOON AND
PERSIST THROUGH THURSDAY. OUR NEXT CHANCES FOR SHOWERS WILL COME
LATE IN THE WEEK INTO THE FIRST PART OF THE WEEKEND.
&&
.HYDROLOGY...
A FAST MOVING COLD FRONT WILL BRING SHOWERS TO THE AREA THROUGH
EARLY THIS MORNING. DRY WEATHER WILL RETURN THIS AFTERNOON AND
PERSIST THROUGH THURSDAY. OUR NEXT CHANCES FOR SHOWERS WILL COME
LATE IN THE WEEK INTO THE FIRST PART OF THE WEEKEND.
THERE WILL BE RISES ON SOME RIVERS AND STREAMS. BASED ON CURRENT
FORECASTS ONLY DELTA DAM ON THE MOHAWK RIVER IS EXPECTED TO EXCEED
FLOOD STAGE AND THIS IS EXPECTED TO OCCUR TUESDAY AFTERNOON.
NATIONAL OPERATIONAL HYDROLOGIC REMOTE SENSING CENTER (NOHRSC)
SHOWS SNOWPACK LEFT ACROSS MAINLY THE SOUTHERN ADIRONDACKS...HIGHER
TERRAIN OF THE EASTERN CATSKILLS AND ACROSS SOUTHERN VERMONT AND
THE NORTHERN BERKSHIRES. THE HIGHEST SNOW WATER EQUIVALENT IS
ACROSS THE HIGHER TERRAIN OF THE SOUTHERN GREEN MOUNTAINS WHERE
THERE IS STILL 6 UP TO POSSIBLY 12 INCHES.
&&
.ALY WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...NONE.
MA...NONE.
VT...NONE.
&&
$$
SYNOPSIS...IAA/11
NEAR TERM...11
SHORT TERM...11
LONG TERM...FRUGIS/KL
AVIATION...FRUGIS/KL
FIRE WEATHER...11
HYDROLOGY...IAA/11
AREA FORECAST DISCUSSION
NWS MOUNT HOLLY NJ
1236 PM EDT TUE APR 14 2015
.SYNOPSIS...
A COLD FRONT WILL TRACK ACROSS THE REGION TODAY, WITH A WAVE OF LOW
PRESSURE PASSING BY TO OUR SOUTH ALONG THE DEPARTING BOUNDARY LATE
TODAY AND TONIGHT. AN AREA OF HIGH PRESSURE WILL THEN BUILD ACROSS
THE NORTHEAST AND MID ATLANTIC STATES THROUGH MIDWEEK. THIS HIGH
PRESSURE IS FORECAST TO MOVE OFFSHORE BY FRIDAY, ALLOWING UNSETTLED
WEATHER TO RETURN FOR THE END OF THE WEEK AND THE WEEKEND.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
12:30 PM UPDATE: MAXIMUM TEMPERATURES WERE TAPPED DOWN BY A DEGREE
OR SO TO ACCOUNT FOR THE STUBBORN CLOUD COVER OVER THE ENTIRE
FORECAST AREA. POPS HAVE ALSO BEEN REDUCED NORTH AND WEST OF THE
I-95 CORRIDOR WHERE RAIN HAS ENDED. THE HRRR CONTINUES TO INDICATE
A SLIGHT NORTHWARD MOVEMENT OF PRECIPITATION THIS AFTERNOON...BUT
THIS WAS DISCOUNTED IN FAVOR THE NAM AND GFS.
A COLD FRONT IS STILL EXPECTED TO SLOWLY SAG SOUTH THROUGH THE
DAY. A LOW PRESSURE SYSTEM IS EXPECTED TO DEVELOP ON THE FRONT,
BUT THIS SHOULD OCCUR ONCE IT IS SOUTH OF OUR REGION. THIS WILL
CONTINUE TO ENHANCE PRECIP OVER THE FAR SOUTHEASTERN PORTIONS OF
THE REGION THROUGH MID AFTERNOON. MODEL SOUNDINGS, ESPECIALLY THE
NAM, ARE SHOWING MODEST ELEVATED INSTABILITY OVER DELMARVA AND
EXTREME SOUTHERN NJ (UP TO 100 J/KG CAPE VALUES). THIS IS NOT
SURPRISING GIVEN THE LATER ARRIVAL OF THE FRONT. STILL, AS
SATURATED AS THE ENTIRE COLUMN WILL BE, AND AS ELEVATED AS THE
INSTABILITY WILL BE, THUNDERSTORMS SEEM VERY UNLIKELY, SO WILL
CONTINUE TO LEAVE OUT OF THE FORECAST.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 AM WEDNESDAY/...
PRECIP COULD LINGER THROUGH THE EARLY EVENING HOURS
ACROSS SOUTHERN DELMARVA, BUT OTHERWISE, SHOULD SEE DRY CONDITIONS
ACROSS MUCH OF THE REGION. ABOUT THE ONLY SIGNIFICANT CHANGE TO THE
FORECAST WAS TO INCREASE SKY COVER IN ANTICIPATION OF THICK CIRRUS
DEVELOPMENT AS THE UPPER LEVEL JET SLIDES EAST.
&&
.LONG TERM /WEDNESDAY THROUGH MONDAY/...
A QUIETER TREND IS EXPECTED AT THE BEGINNING OF THIS PERIOD AS
SURFACE HIGH PRESSURE CENTERED OVER SOUTHEASTERN CANADA WILL BE
BUILDING DOWN ACROSS THE NORTHEAST TO MID ATLANTIC STATES THROUGH
WEDNESDAY AND THURSDAY. WITH THE HIGH PRESSURE CENTERED TO OUR NORTH
THROUGH WEDNESDAY, AMPLE SUN WITH SLIGHTLY ABOVE AVERAGE
TEMPERATURES AND MODEST NORTHERLY WINDS ARE EXPECTED. MAXIMUM
TEMPERATURES ARE ANTICIPATED TO REACH THE MIDDLE TO UPPER 60S ACROSS
MOST OF THE REGION, WITH SOMEWHAT COOLER UPPER 50S TO NEAR 60 DEGREE
READINGS INTO THE POCONOS AND ALONG THE COASTS OF NEW JERSEY AND
DELAWARE. WHILE GENERALLY QUIET CONDITIONS ARE EXPECTED TO CONTINUE
INTO THURSDAY, THE CENTER OF THE SURFACE HIGH PRESSURE IS PROGGED TO
BE PASSING OFF THE COAST OF THE NORTHEAST STATES, AND THIS WILL
ALLOW FOR MORE OF AN EASTERLY SURFACE FLOW TO SET-UP ACROSS OUR
REGION, BRINGING A RETURN TO MORE CLOUDS AND DAYTIME TEMPERATURES
NEAR TO SLIGHTLY BELOW MID-APRIL AVERAGES. MAX TEMPS FOR THURSDAY
SHOULD BE MORE IN THE UPPER 50S TO LOWER 60S ACROSS THE REGION, WITH
COOLER LOW/MID 50S POSSIBLE INTO THE POCONOS AND ALONG THE COAST.
FROM HERE, A MORE UNSETTLED PATTERN IS EXPECTED TO CLOSE OUT THE
WEEK AND EXTEND THROUGH THE WEEKEND AND POSSIBLY MONDAY. WITH THE
PREVIOUSLY MENTIONED HIGH PRESSURE EAST AND OFFSHORE, A SHORTWAVE
UPPER-LEVEL TROUGH IS PROGGED TO PASS OVER THE REGION FRIDAY,
BRINGING SCATTERED RAIN SHOWERS. INTO THE WEEKEND AND MONDAY, THERE
CONTINUES TO BE A RATHER LARGE SPREAD OF MODEL SOLUTIONS REGARDING
THE TIMING, EVOLUTION, AND TRACK OF POSSIBLE LOW PRESSURE AND ITS
ASSOCIATED FRONTAL BOUNDARIES DEVELOPING AND MOVING IN A SPLIT FLOW
PATTERN. THIS LEADS TO GREATER UNCERTAINTY IN THE TIMING AND AMOUNT
OF PRECIPITATION THAT COULD AFFECT OUR FORECAST AREA OVER THE
WEEKEND AND INTO MONDAY. THEREFORE, WE MAINLY TOOK A BLEND OF WPC
GUIDANCE WITH CONTINUITY FOR THIS TIMEFRAME, WITH MAINLY CHANCE POPS
IN PLACE DURING THIS TIMEFRAME. FOR COMPARISON SAKE, THE LATEST
ECMWF WOULD HAVE A RELATIVELY DRY WEEKEND, WITH THE MAIN
PRECIPITATION EVENT GOING INTO MONDAY. MEANWHILE, THE GFS HAS DONE A
BIT OF A FLIP-FLOP, WITH SUNDAY INTO MONDAY NOW BEING THE WETTER
PERIOD AND SATURDAY BEING RELATIVELY DRY. AS WE GET CLOSER IN TIME
TO THE UPCOMING WEEKEND, MODEL RUNS WILL HOPEFULLY SHOW MORE
CONSISTENCY AND RESOLVE THE TIMING AND AMOUNT OF POTENTIAL PRECIP TO
AFFECT OUR AREA IN THE SPLIT FLOW PATTERN.
&&
.AVIATION /18Z TUESDAY THROUGH SUNDAY/...
THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE,
KRDG, KILG, KMIV, KACY AND SURROUNDING AREAS.
THE COLD FRONT HAS NOW MOVED THROUGH ALL TAF SITES EXCEPT ACY AND
MIV, WITH VFR CONDITIONS RETURNING BEHIND THE FRONT. KMIV AND
KACY COULD SEE A FEW HOURS OF IFR CONDITIONS, AND SHRA LINGERING
FOR MUCH OF THE AFTERNOON. CONDITIONS SHOULD IMPROVE TO VFR
BETWEEN 18 AND 00Z, AND REMAIN VFR FOR THE REST OF THE TAF PERIOD.
OUTLOOK...
WEDNESDAY...VFR CONDITIONS ARE EXPECTED WITH NORTHERLY WINDS.
THURSDAY...CONTINUED VFR, WITH EASTERLY TO SOUTHEAST WINDS.
THURSDAY NIGHT AND FRIDAY...CONDITIONS LOWERING TO MVFR WITH
SCATTERED RAIN SHOWERS.
SATURDAY...SUB-VFR POSSIBLE IN ISOLATED/SCATTERED SHOWERS. LOW
CONFIDENCE.
&&
.MARINE...
SOUTHERLY WINDS WILL SHIFT ABRUPTLY TO NORTHWESTERLY WITH THE
ARRIVAL OF A COLD FRONT LATER TODAY. WIND GUSTS NEAR OR ABOVE 20KT
ARE POSSIBLE THROUGH THE EVENING AND OVERNIGHT HOURS. FOR THE
COASTAL WATERS FROM FENWICK ISLAND UP TO ATLANTIC CITY, SCA
CONDITIONS ARE LIKELY BEGINNING LATE TONIGHT. WAVES WILL SUBSEQUENTLY
INCREASE WITH THE WIND SPEED INCREASE.
OUTLOOK...
WEDNESDAY...WIND GUSTS TO AROUND 20 KNOTS AND SEAS AROUND 5 FEET ARE
EXPECTED TO CONTINUE FOR OUR SOUTHERN COASTAL WATERS FROM GREAT EGG
INLET SOUTH TO FENWICK ISLAND DE, AND A SMALL CRAFT ADVISORY LASTS
INTO EARLY AFTERNOON. OTHERWISE, WINDS AND SEAS ARE FORECAST TO BE
SUB-ADVISORY FOR THE REST OF THE COASTAL WATERS AND DELAWARE BAY.
THURSDAY...SUB-ADVISORY CONDITIONS ARE EXPECTED.
FRIDAY AND SATURDAY...MORE UNCERTAINTY EXISTS DURING THIS PERIOD,
BUT SEAS AT OR ABOVE 5 FT ARE POSSIBLE FOR THE COASTAL WATERS,
ESPECIALLY ON SATURDAY.
&&
.FIRE WEATHER...
FOR TODAY...LOCATIONS NORTH AND WEST OF THE FALL LINE,
INCLUDING LEHIGH VALLEY, NORTHWEST NJ, AND THE POCONOS, COULD SEE
MINIMUM AFTERNOON RELATIVE HUMIDITY VALUES NEAR 30 PERCENT. HOWEVER,
WITH WETTING RAINS EXPECTED THIS MORNING, AND WINDS GENERALLY LESS
THAN 10 MPH, NO FIRE WEATHER CONCERNS ARE ANTICIPATED AT THIS TIME.
FOR WEDNESDAY...WHILE RELATIVE HUMIDITY VALUES WILL LIKELY DROP INTO
THE 20S ACROSS MUCH OF THE AREA, WINDS ARE NOT EXPECTED TO
FREQUENTLY GUST ABOVE 20 MPH. IN ADDITION, MUCH OF THE REGION IS
EXPECTED TO RECEIVE WETTING RAINS DURING TUESDAY AND TUESDAY NIGHT,
WHICH SHOULD HELP TO MOISTEN THE FINE FUELS.
&&
.HYDROLOGY...
ACROSS DELMARVA AND SOUTHERN NEW JERSEY, GENERALLY ALONG AND
SOUTHEAST OF THE I95 CORRIDOR, STILL WATCHING FOR HEAVY RAIN
POTENTIAL FROM MID MORNING THROUGH LATE THIS AFTERNOON, ALTHOUGH
TIMING IS HIGHLY DEPENDENT ON HOW QUICKLY AND HOW FAR THE FRONT WILL
SLIDE SOUTH. NEAR THE FRONT, RELATIVELY HIGH MEAN RH, PWATS WELL
ABOVE NORMAL, AND A DEEP WARM CLOUD LAYER WILL ENHANCE THE HEAVY
RAIN THREAT. THE ONLY QUESTION IS HOW LONG THE THREAT WILL LAST. SO
FOR NOW, WILL KEEP THE SAME WORDING IN THE HWO.
&&
.PHI WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NJ...NONE.
DE...NONE.
MD...NONE.
MARINE...SMALL CRAFT ADVISORY FROM 2 AM TO 2 PM EDT WEDNESDAY FOR
ANZ453>455.
&&
$$
SYNOPSIS...KLINE
NEAR TERM...GAINES/JOHNSON
SHORT TERM...JOHNSON
LONG TERM...KLINE
AVIATION...JOHNSON/KLINE
MARINE...JOHNSON/KLINE
FIRE WEATHER...
HYDROLOGY...
AREA FORECAST DISCUSSION
NWS CHARLESTON SC
726 AM EDT TUE APR 14 2015
.SYNOPSIS...
A COLD FRONT WILL APPROACH FROM THE NORTH TODAY AND TONIGHT THEN
PASS THROUGH THE AREA WEDNESDAY. A WEDGE OF HIGH PRESSURE WILL
DEVELOP BEHIND THE FRONT AND STRENGTHEN THURSDAY AS A COASTAL
TROUGH DEVELOPS OFFSHORE. THE TROUGH WILL LIFT NORTHEAST UP THE
COAST FRIDAY...BEFORE A WEAK COLD FRONT CROSSES THE REGION LATE
SATURDAY. ANOTHER STORM SYSTEM IS EXPECTED TO IMPACT THE AREA LATE
WEEKEND.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
THE FORECAST PHILOSOPHY HAS CHANGED LITTLE FROM EARLIER THIS
MORNING. THE LATEST H3R AND RAP STILL SUPPORT GULF COAST SEA
BREEZE CONVECTION MOVING IN LATE...BUT DEGREE OF COVERAGE REMAINS
IN QUESTION. OPTED NOT TO MAKE ANY CHANGES TO THE GOING FORECAST
FOR NOW. MADE MINOR CHANGES TO SHORT TERM GRIDS FOR THE SUNRISE
UPDATE.
WARM FRONTAL REMNANTS ARE NOW NORTH OF THE FORECAST AREA PER
14/07Z SURFACE OBSERVATIONS. THE DECAYING BOUNDARY WILL CONTINUE
TO LIFT NORTH TODAY AND DISSIPATE AS LOW PRESSURE MOVES INTO THE
SOUTHERN APPALACHIANS ALONG AN ADVANCING COLD FRONT. 14/00Z UPPER
ANALYSIS DID NOT IDENTIFY ANY SIGNIFICANT UPSTREAM IMPULSES THAT
WILL CROSS THE AREA AT PEAK HEATING...SO EXPECT A MAINLY DIURNAL
CONVECTIVE PATTERN TO PREVAIL WITH THE AREA REMAINING ALONG THE
CONVERGENT SIDE OF THE MID-LEVEL RIDGE AXIS.
THERE APPEARS TO BE TWO FAVORED AREAS FOR ENHANCED CONVECTIVE
DEVELOPMENT TODAY. THE FIRST WILL BE ACROSS THE INTERIOR
PORTIONS OF SOUTHEAST SOUTH CAROLINA...ROUGHLY IN THE WALTERBORO-
JAMESTOWN...NORTH CHARLESTON CORRIDOR WHERE LOW-LEVEL CONVERGENCE
WILL BECOME MAXIMIZED BETWEEN THE INLAND MOVING SEA BREEZE AND THE
LAKE BREEZES AROUND LAKES MARION AND MOULTRIE. THE OTHER WILL BE
THE AREA SOUTH OF I-16...ESPECIALLY NEAR THE ALTAMAHA RIVER...WHERE
SCATTERED CONVECTION ASSOCIATED WITH THE GULF COAST SEA BREEZE
MOVING NORTHEAST OFF APALACHEE BAY WILL LIKELY APPROACH LATE AND
INTERACT WITH THE ATLANTIC SEA BREEZE. IT IS HARD TO JUSTIFY POPS
ANY HIGHER THAN 40-50 PERCENT IN THESE AREAS IN THE ABSENCE OF A
SIGNIFICANT UPPER LEVEL FORCING MECHANISM...BUT LOCALLY HIGHER
POPS MAY EVENTUALLY BE NEEDED AS SHORT TERM CONVECTIVE AND SURFACE
MESOSCALE TRENDS BECOME MORE APPARENT LATER TODAY. SHOWERS/TSTMS
WILL BE MORE SPORADIC AND MAINLY DRIVEN BY AIRMASS DESTABILIZATION
FOR THE REMAINING PORTIONS OF THE FORECAST AREA. THIS JUSTIFIES
POPS OF 20-30 PERCENT. THERMODYNAMIC PROFILES ARE NOT OVERLY
IMPRESSIVE PER MODIFIED MODEL POINT SOUNDINGS SO THE RISK FOR
SEVERE TSTMS LOOK MINIMAL...ALTHOUGH GUSTY WINDS...TORRENTIAL
DOWNPOURS AND CLOUD-TO-GROUND LIGHTNING STRIKES WILL STILL POSE A
HAZARD.
EXTENSIVE CLOUD COVER THIS MORNING WILL GRADUALLY THIN WITH TIME
WITH SKIES LIKELY BECOMING PARTLY CLOUDY FOR MANY AREAS. THIS
INCREASED INSOLATION COUPLED WITH 850 HPA TEMPERATURES RISING TO
14-16C WILL SUPPORT HIGHS IN THE MID-UPPER 80S. THERE IS EVEN AN
OUTSIDE SHOT OF A FEW 90 DEGREE READINGS IN THE I-95 CORRIDOR FROM
ROUGHLY SAVANNAH SOUTH TO DARIEN...INCLUDING LUDOWICI AND
HINESVILLE. THE RAP/NAM12 AND H3R ALL SHOW READINGS 87-89 DEGREES
IN THIS AREA BEFORE THE ARRIVAL OF THE ATLANTIC SEA BREEZE AND
CONVECTION MOVING IN FROM THE SOUTHWEST.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH FRIDAY/...
TONIGHT...DIURNAL SHOWER/TSTM ACTIVITY WILL GRADUALLY DIMINISH WITH
THE LOSS OF INSOLATION...ALTHOUGH IT MAY TAKE A GOOD PORTION OF
THE EVENING FOR THE ACTIVITY PROPAGATING IN AHEAD OF THE GULF
COAST SEA BREEZE TO PUSH OFF THE GEORGIA COAST. EXPECT MAINLY DRY
CONDITIONS TO PREVAIL FOR A GOOD PORTION THE NIGHT. A BACKDOOR
COLD FRONT WILL APPROACH FROM THE NORTH LATE...BUT THIS BOUNDARY
SHOULD REMAIN NORTH OF THE SANTEE RIVER THROUGH SUNRISE. THERE MAY
BE JUST ENOUGH LOW-LEVEL CONVERGENCE AHEAD OF THE FRONT TO SUPPORT
ISOLATED SHOWERS ACROSS THE CHARLESTON TRI-COUNTY AREA AFTER 4-5
AM...SO SLIGHT CHANCE POPS WILL BE DEPICTED IN THIS AREA. IT WILL
OTHERWISE BE ANOTHER WARM AND HUMID NIGHT WITH LOWS ONLY DROPPING
INTO THE UPPER 60S.
WEDNESDAY...AT DAYBREAK A BACKDOOR COLD FRONT WILL BE SLOWLY
DESCENDING SOUTH INTO THE NORTHERN PORTIONS OF THE FORECAST AREA. AS
THE FRONT SINKS FURTHER SOUTH THROUGH THE DAY...A WEDGE OF HIGH
PRESSURE WILL DEVELOP BEHIND IT. CONTINUED DEEP MOISTURE FEED FROM
THE TROPICAL PACIFIC AND GULF OF MEXICO WILL RESULT IN PWATS OF
AROUND 1.75 INCHES...OR ABOUT 2 STANDARD DEVIATIONS ABOVE NORMAL.
THIS IN COMBINATION WITH SHORTWAVE ENERGY EJECTING OUT THE SOUTHWEST
FLOW WILL RESULT IN HIGH CHANCE/LIKELY POPS. WEAK INSTABILITY MAINLY
IN SOUTHEAST GEORGIA WILL KEEP A SLIGHT CHANCE OF THUNDER MENTION IN
THE FORECAST IN THE AFTERNOON. OTHER CONVECTIVE PARAMETERS ARE
RATHER POOR SO SEVERE THREAT IS PRETTY LOW. BY SUNSET...THE FRONT
SHOULD BE LOCATED NEAR OR SOUTH OF THE ALTAMAHA. HIGH TEMPERATURES
WILL RANGE FROM THE MID 70S IN OUR NORTHERN ZONES...TO AROUND 80
SOUTH. WEDNESDAY NIGHT...THE ILL-DEFINED FRONT WILL TRANSITION INTO
A COASTAL TROUGH...ACTING TO STRENGTHEN THE INLAND HIGH PRESSURE
WEDGE. ELEVATED MOISTURE AND ENHANCED LOW LEVEL CONVERGENCE WILL
KEEP SHOWERS IN THE FORECAST OVERNIGHT. LOWS WILL BE RANGE FROM THE
UPPER 50S TO MID 60S.
THURSDAY...THE COASTAL TROUGH WILL LIKELY CLOSE OFF AS A SURFACE LOW
AND BEGIN TO MOVE NORTHEAST UP THE COAST. HIGHEST RAIN CHANCES WILL
BE IN MORNING/EARLY AFTERNOON BEFORE THE BEST MOISTURE SHIFTS NORTH
WITH THE SURFACE LOW. COOL NORTH/NORTHEAST FLOW AND OVERCAST SKIES
WILL KEEP HIGHS BELOW NORMAL...RANGING FROM THE UPPER 60S TO LOW/MID
70S. THURSDAY NIGHT...THE WEDGE WILL BEGIN TO WEAKEN AS THE LOW
CONTINUES TO LIFT NORTHEAST ALONG THE CAROLINA COAST. THERE WILL
LIKELY BE SOMEWHAT OF A BREAK IN PRECIPITATION AND FORECAST
CURRENTLY ONLY HAS SLIGHT CHANCE/CHANCE POPS. LOWS WILL BE IN THE
UPPER 50S/LOW 60S.
FRIDAY...FRIDAY WILL BE MORE OF A TRANSITIONAL DAY WITH A RATHER
WEAK/DIFFUSE PRESSURE PATTERN. DESPITE THE FORECAST AREA REMAINING
UNDER THE PERSISTENT MOISTURE FEED...RAIN CHANCES WILL BE CAPPED AT
20-30 PERCENT SINCE THERE DOES NOT SEEM TO BE MUCH FOCUS OR FORCING
CONVECTION. HIGH TEMPERATURES WILL MODERATE BACK TO NORMAL...IN THE
MID/UPPER 70S.
&&
.LONG TERM /FRIDAY NIGHT THROUGH MONDAY/...
MODELS HAVE BEEN PRETTY INCONSISTENT IN THE LONG TERM PERIOD SO
FORECAST CONFIDENCE IS QUITE LOW. A WEAK COLD FRONT WILL DROP
THROUGH THE REGION LATE SATURDAY. TRANSIENT HIGH PRESSURE WILL
PREVAIL ON SUNDAY AHEAD OF THE NEXT STORM SYSTEM BREWING IN THE
MIDWEST WHICH WILL AFFECT THE FORECAST AREA EARLY NEXT WEEK.
ELEVATED MOISTURE AND A SERIES OF UPPER LEVEL DISTURBANCES WILL
KEEP RAIN CHANCES IN THE FORECAST FOR MUCH OF THE PERIOD.
&&
.AVIATION /12Z TUESDAY THROUGH SATURDAY/...
LOW CLOUDS AT KCHS ARE POISED TO MIX OUT 12-13Z. VFR DOMINATING
KCHS/KSAV FOR MUCH OF THE DAY. SHOWERS/TSTMS COULD IMPACT THE
TERMINAL AT ANY TIME TODAY...BUT CELLS LOOK TRANSIENT ENOUGH THAT
ANY IMPACTS WILL BE BRIEF. COULD SEE A MORE ORGANIZED TSTM CLUSTER
APPROACH KSAV LATE AFTERNOON/SUNSET AS THE GULF SEA BREEZE
APPROACHES FROM THE SOUTHWEST. CONFIDENCE IN TIMING IS TOO LOW TO
INCLUDE A MENTION JUST YET. MVFR CIGS ARE POSSIBLE JUST BEFORE
SUNRISE WEDNESDAY AT KCHS AS A COLD FRONT APPROACHES FROM THE
NORTH.
EXTENDED AVIATION OUTLOOK...FLIGHT RESTRICTIONS LIKELY AT TIMES
THROUGH THE WEEK AS PERIODIC SHOWERS/TSTMS IMPACT THE TERMINALS.
&&
.MARINE...
TODAY...SOUTH TO SOUTHWEST WINDS WILL PREVAIL TODAY WITH WINDS
GENERALLY 10 KT OR LESS. A ROBUST SEA BREEZE WILL TAKE SHAPE ALONG
THE BEACHES BY EARLY AFTERNOON...WHICH WILL ENHANCE WIND FIELDS
NEAR THE BEACHES AND THE CHARLESTON HARBOR. WINDS SHOULD REACH AS
HIGH AS 15 KT IN THE CHARLESTON HARBOR FOR MID-LATE AFTERNOON AS
THE SEA BREEZE MOVES INLAND. LOWS WILL AVERAGE 2-4 FT...HIGHEST
OFFSHORE WATERS.
TONIGHT...SOUTHWEST WINDS AROUND 10 KT WILL PREVAIL AHEAD OF AN
ADVANCING COLD FRONT. SEAS WILL AVERAGE 2-3 FT.
WEDNESDAY THROUGH MONDAY...A BACKDOOR COLD FRONT WILL DESCEND SOUTH
ACROSS THE WATERS ON WEDNESDAY...WITH A WEDGE OF HIGH PRESSURE
BUILDING IN ITS WAKE. WEDNESDAY NIGHT INTO THURSDAY...A COASTAL
TROUGH WILL DEVELOP OFFSHORE ALLOWING THE INLAND WEDGE TO
STRENGTHEN. GIVEN A TIGHTENING PRESSURE GRADIENT AND DECENT PRESSURE
RISES...WINDS AND SEAS WILL BUILD. SMALL CRAFT ADVISORIES MAY BE
NEEDED FOR WEDNESDAY NIGHT INTO THURSDAY...ESPECIALLY ACROSS THE
SOUTH CAROLINA COASTAL WATERS...AS NORTHEAST WINDS GUST TO 25 KT AND
SEAS BUILD TO 4-6 FEET. IN ADDITION...THERE WILL BE AN ENHANCED RISK
OF RIP CURRENTS DURING THIS TIME. THURSDAY NIGHT...THE COASTAL
TROUGH WILL CLOSE OFF AND BEGIN TO MOVE NORTHEAST UP THE COAST
ALLOWING THE PRESSURE GRADIENT TO RELAX. TRANSIENT HIGH PRESSURE
WILL PREVAIL FRIDAY BEFORE A WEAK COLD FRONT IMPACTS THE WATERS
SATURDAY NIGHT. AT THIS TIME...WINDS/SEAS ARE EXPECTED TO REMAIN
BELOW HEADLINE CRITERIA. ANOTHER STORM SYSTEM IS EXPECTED TO AFFECT
REGION EARLY NEXT WEEK.
&&
.TIDES/COASTAL FLOODING...
A COMBINATION OF ASTRONOMICAL HIGH TIDES AND LEFTOVER NORTHEAST
WINDS/SWELL WILL RESULT IN A THREAT FOR SHALLOW COASTAL FLOODING
NEAR THE TIME OF HIGH TIDE THURSDAY AND FRIDAY EVENING...PERHAPS
EXTENDING INTO THE SATURDAY EVENING HIGH TIDE.
&&
.CHS WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
SC...NONE.
MARINE...NONE.
&&
$$
ST/ECT
AREA FORECAST DISCUSSION
NWS CHARLESTON SC
412 AM EDT TUE APR 14 2015
.SYNOPSIS...
A COLD FRONT WILL APPROACH FROM THE NORTH TODAY AND TONIGHT THEN
PASS THROUGH THE AREA WEDNESDAY. A WEDGE OF HIGH PRESSURE WILL
DEVELOP BEHIND THE FRONT AND STRENGTHEN THURSDAY AS A COASTAL
TROUGH DEVELOPS OFFSHORE. THE TROUGH WILL LIFT NORTHEAST UP THE
COAST FRIDAY...BEFORE A WEAK COLD FRONT CROSSES THE REGION LATE
SATURDAY. ANOTHER STORM SYSTEM IS EXPECTED TO IMPACT THE AREA LATE
WEEKEND.
&&
.NEAR TERM /THROUGH TODAY/...
WARM FRONTAL REMNANTS ARE NOW NORTH OF THE FORECAST AREA PER
14/07Z SURFACE OBSERVATIONS. THE DECAYING BOUNDARY WILL CONTINUE
TO LIFT NORTH TODAY AND DISSIPATE AS LOW PRESSURE MOVES INTO THE
SOUTHERN APPALACHIANS ALONG AN ADVANCING COLD FRONT. 14/00Z UPPER
ANALYSIS DID NOT IDENTIFY ANY SIGNIFICANT UPSTREAM IMPULSES THAT
WILL CROSS THE AREA AT PEAK HEATING...SO EXPECT A MAINLY DIURNAL
CONVECTIVE PATTERN TO PREVAIL WITH THE AREA REMAINING ALONG THE
CONVERGENT SIDE OF THE MID-LEVEL RIDGE AXIS.
THERE APPEARS TO BE TWO FAVORED AREAS FOR ENHANCED CONVECTIVE
DEVELOPMENT TODAY. THE FIRST WILL BE ACROSS THE INTERIOR
PORTIONS OF SOUTHEAST SOUTH CAROLINA...ROUGHLY IN THE WALTERBORO-
JAMESTOWN...NORTH CHARLESTON CORRIDOR WHERE LOW-LEVEL CONVERGENCE
WILL BECOME MAXIMIZED BETWEEN THE INLAND MOVING SEA BREEZE AND THE
LAKE BREEZES AROUND LAKES MARION AND MOULTRIE. THE OTHER WILL BE
THE AREA SOUTH OF I-16...ESPECIALLY NEAR THE ALTAMAHA RIVER...WHERE
SCATTERED CONVECTION ASSOCIATED WITH THE GULF COAST SEA BREEZE
MOVING NORTHEAST OFF APALACHEE BAY WILL LIKELY APPROACH LATE AND
INTERACT WITH THE ATLANTIC SEA BREEZE. IT IS HARD TO JUSTIFY POPS
ANY HIGHER THAN 40-50 PERCENT IN THESE AREAS IN THE ABSENCE OF A
SIGNIFICANT UPPER LEVEL FORCING MECHANISM...BUT LOCALLY HIGHER
POPS MAY EVENTUALLY BE NEEDED AS SHORT TERM CONVECTIVE AND SURFACE
MESOSCALE TRENDS BECOME MORE APPARENT LATER TODAY. SHOWERS/TSTMS
WILL BE MORE SPORADIC AND MAINLY DRIVEN BY AIRMASS DESTABILIZATION
FOR THE REMAINING PORTIONS OF THE FORECAST AREA. THIS JUSTIFIES
POPS OF 20-30 PERCENT. THERMODYNAMIC PROFILES ARE NOT OVERLY
IMPRESSIVE PER MODIFIED MODEL POINT SOUNDINGS SO THE RISK FOR
SEVERE TSTMS LOOK MINIMAL...ALTHOUGH GUSTY WINDS...TORRENTIAL
DOWNPOURS AND CLOUD-TO-GROUND LIGHTNING STRIKES WILL STILL POSE A
HAZARD.
EXTENSIVE CLOUD COVER THIS MORNING WILL GRADUALLY THIN WITH TIME
WITH SKIES LIKELY BECOMING PARTLY CLOUDY FOR MANY AREAS. THIS
INCREASED INSOLATION COUPLED WITH 850 HPA TEMPERATURES RISING TO
14-16C WILL SUPPORT HIGHS IN THE MID-UPPER 80S. THERE IS EVEN AN
OUTSIDE SHOT OF A FEW 90 DEGREE READINGS IN THE I-95 CORRIDOR FROM
ROUGHLY SAVANNAH SOUTH TO DARIEN...INCLUDING LUDOWICI AND
HINESVILLE. THE RAP/NAM12 AND H3R ALL SHOW READINGS 87-89 DEGREES
IN THIS AREA BEFORE THE ARRIVAL OF THE ATLANTIC SEA BREEZE AND
CONVECTION MOVING IN FROM THE SOUTHWEST.
&&
.SHORT TERM /TONIGHT THROUGH FRIDAY/...
TONIGHT...DIURNAL SHOWER/TSTM ACTIVITY WILL GRADUALLY DIMINISH WITH
THE LOSS OF INSOLATION...ALTHOUGH IT MAY TAKE A GOOD PORTION OF
THE EVENING FOR THE ACTIVITY PROPAGATING IN AHEAD OF THE GULF
COAST SEA BREEZE TO PUSH OFF THE GEORGIA COAST. EXPECT MAINLY DRY
CONDITIONS TO PREVAIL FOR A GOOD PORTION THE NIGHT. A BACKDOOR
COLD FRONT WILL APPROACH FROM THE NORTH LATE...BUT THIS BOUNDARY
SHOULD REMAIN NORTH OF THE SANTEE RIVER THROUGH SUNRISE. THERE MAY
BE JUST ENOUGH LOW-LEVEL CONVERGENCE AHEAD OF THE FRONT TO SUPPORT
ISOLATED SHOWERS ACROSS THE CHARLESTON TRI-COUNTY AREA AFTER 4-5
AM...SO SLIGHT CHANCE POPS WILL BE DEPICTED IN THIS AREA. IT WILL
OTHERWISE BE ANOTHER WARM AND HUMID NIGHT WITH LOWS ONLY DROPPING
INTO THE UPPER 60S.
WEDNESDAY...AT DAYBREAK A BACKDOOR COLD FRONT WILL BE SLOWLY
DESCENDING SOUTH INTO THE NORTHERN PORTIONS OF THE FORECAST AREA. AS
THE FRONT SINKS FURTHER SOUTH THROUGH THE DAY...A WEDGE OF HIGH
PRESSURE WILL DEVELOP BEHIND IT. CONTINUED DEEP MOISTURE FEED FROM
THE TROPICAL PACIFIC AND GULF OF MEXICO WILL RESULT IN PWATS OF
AROUND 1.75 INCHES...OR ABOUT 2 STANDARD DEVIATIONS ABOVE NORMAL.
THIS IN COMBINATION WITH SHORTWAVE ENERGY EJECTING OUT THE SOUTHWEST
FLOW WILL RESULT IN HIGH CHANCE/LIKELY POPS. WEAK INSTABILITY MAINLY
IN SOUTHEAST GEORGIA WILL KEEP A SLIGHT CHANCE OF THUNDER MENTION IN
THE FORECAST IN THE AFTERNOON. OTHER CONVECTIVE PARAMETERS ARE
RATHER POOR SO SEVERE THREAT IS PRETTY LOW. BY SUNSET...THE FRONT
SHOULD BE LOCATED NEAR OR SOUTH OF THE ALTAMAHA. HIGH TEMPERATURES
WILL RANGE FROM THE MID 70S IN OUR NORTHERN ZONES...TO AROUND 80
SOUTH. WEDNESDAY NIGHT...THE ILL-DEFINED FRONT WILL TRANSITION INTO
A COASTAL TROUGH...ACTING TO STRENGTHEN THE INLAND HIGH PRESSURE
WEDGE. ELEVATED MOISTURE AND ENHANCED LOW LEVEL CONVERGENCE WILL
KEEP SHOWERS IN THE FORECAST OVERNIGHT. LOWS WILL BE RANGE FROM THE
UPPER 50S TO MID 60S.
THURSDAY...THE COASTAL TROUGH WILL LIKELY CLOSE OFF AS A SURFACE LOW
AND BEGIN TO MOVE NORTHEAST UP THE COAST. HIGHEST RAIN CHANCES WILL
BE IN MORNING/EARLY AFTERNOON BEFORE THE BEST MOISTURE SHIFTS NORTH
WITH THE SURFACE LOW. COOL NORTH/NORTHEAST FLOW AND OVERCAST SKIES
WILL KEEP HIGHS BELOW NORMAL...RANGING FROM THE UPPER 60S TO LOW/MID
70S. THURSDAY NIGHT...THE WEDGE WILL BEGIN TO WEAKEN AS THE LOW
CONTINUES TO LIFT NORTHEAST ALONG THE CAROLINA COAST. THERE WILL
LIKELY BE SOMEWHAT OF A BREAK IN PRECIPITATION AND FORECAST
CURRENTLY ONLY HAS SLIGHT CHANCE/CHANCE POPS. LOWS WILL BE IN THE
UPPER 50S/LOW 60S.
FRIDAY...FRIDAY WILL BE MORE OF A TRANSITIONAL DAY WITH A RATHER
WEAK/DIFFUSE PRESSURE PATTERN. DESPITE THE FORECAST AREA REMAINING
UNDER THE PERSISTENT MOISTURE FEED...RAIN CHANCES WILL BE CAPPED AT
20-30 PERCENT SINCE THERE DOES NOT SEEM TO BE MUCH FOCUS OR FORCING
CONVECTION. HIGH TEMPERATURES WILL MODERATE BACK TO NORMAL...IN THE
MID/UPPER 70S.
&&
.LONG TERM /FRIDAY NIGHT THROUGH MONDAY/...
MODELS HAVE BEEN PRETTY INCONSISTENT IN THE LONG TERM PERIOD SO
FORECAST CONFIDENCE IS QUITE LOW. A WEAK COLD FRONT WILL DROP
THROUGH THE REGION LATE SATURDAY. TRANSIENT HIGH PRESSURE WILL
PREVAIL ON SUNDAY AHEAD OF THE NEXT STORM SYSTEM BREWING IN THE
MIDWEST WHICH WILL AFFECT THE FORECAST AREA EARLY NEXT WEEK.
ELEVATED MOISTURE AND A SERIES OF UPPER LEVEL DISTURBANCES WILL
KEEP RAIN CHANCES IN THE FORECAST FOR MUCH OF THE PERIOD.
&&
.AVIATION /06Z TUESDAY THROUGH SATURDAY/...
KCHS...WARM FRONT NOW NORTH OF THE TERMINAL. WATCHING FOR A PERIOD
OF LOW CLOUDS OVER THE NEXT FEW HOURS...MAINLY 09-12Z. GUIDANCE
MIXED DURING THIS TIME...BUT GENERALLY FAVORS VFR. WITH AREA
OBSERVATIONS SHOWING SOME MVFR CIGS AROUND...WILL SHOW MVFR CIGS
09-12Z WITH A TEMPO VFR DURING THAT TIME. VFR FROM SUNRISE ON.
SCATTERED SHOWERS/TSTMS WILL LIKELY DEVELOP NORTHWEST OF THE
TERMINAL THIS AFTERNOON. CONFIDENCE TO LOW TO INCLUDE A MENTION
ATTM AND WILL BE REEVALUATED WITH THE 12Z TAF CYCLE.
KSAV...IFR CIGS ARE VERY NEAR THE TERMINAL...MAINLY TO THE NORTH.
THERE IS A SOLID CHANCE THESE CIGS WILL BUILD DOWN TO IMPACT THE
TERMINALS FOR A FEW HOURS PER RAP SOUNDINGS. WILL SHOW A TEMPO
GROUP FROM 08-10Z OF IFR BKN008 TO COVER THIS. OTHERWISE...EXPECT
VFR CONDITIONS TO PREVAIL. IF IFR CIGS TO DEVELOP...THEY MAY
LINGER LONGER THAN INDICATED...BUT THIS IS AGAINST THE GUIDANCE
MEAN. A CLUSTER OF SHOWERS/TSTMS DEVELOPING ALONG THE GULF SEA
BREEZE MAY APPROACH THE TERMINAL AFTER SUNSET. LOW CONFIDENCE
SHOWERS/TSTMS WILL REACH THAT FAR WITH DIMINISHING INSTABILITY
LATE AFTERNOON BEHIND THE ATLANTIC SEA BREEZE. WILL NOT INCLUDE A
MENTION ATTM AND WILL BE REEVALUATED WITH THE 12Z TAF CYCLE.
EXTENDED AVIATION OUTLOOK...FLIGHT RESTRICTIONS LIKELY AT TIMES
THROUGH THE WEEK AS PERIODIC SHOWERS/TSTMS IMPACT THE TERMINALS.
&&
.MARINE...
TODAY...SOUTH TO SOUTHWEST WINDS WILL PREVAIL TODAY WITH WINDS
GENERALLY 10 KT OR LESS. A ROBUST SEA BREEZE WILL TAKE SHAPE ALONG
THE BEACHES BY EARLY AFTERNOON...WHICH WILL ENHANCE WIND FIELDS
NEAR THE BEACHES AND THE CHARLESTON HARBOR. WINDS SHOULD REACH AS
HIGH AS 15 KT IN THE CHARLESTON HARBOR FOR MID-LATE AFTERNOON AS
THE SEA BREEZE MOVES INLAND. LOWS WILL AVERAGE 2-4 FT...HIGHEST
OFFSHORE WATERS.
TONIGHT...SOUTHWEST WINDS AROUND 10 KT WILL PREVAIL AHEAD OF AN
ADVANCING COLD FRONT. SEAS WILL AVERAGE 2-3 FT.
WEDNESDAY THROUGH MONDAY...A BACKDOOR COLD FRONT WILL DESCEND SOUTH
ACROSS THE WATERS ON WEDNESDAY...WITH A WEDGE OF HIGH PRESSURE
BUILDING IN ITS WAKE. WEDNESDAY NIGHT INTO THURSDAY...A COASTAL
TROUGH WILL DEVELOP OFFSHORE ALLOWING THE INLAND WEDGE TO
STRENGTHEN. GIVEN A TIGHTENING PRESSURE GRADIENT AND DECENT PRESSURE
RISES...WINDS AND SEAS WILL BUILD. SMALL CRAFT ADVISORIES MAY BE
NEEDED FOR WEDNESDAY NIGHT INTO THURSDAY...ESPECIALLY ACROSS THE
SOUTH CAROLINA COASTAL WATERS...AS NORTHEAST WINDS GUST TO 25 KT AND
SEAS BUILD TO 4-6 FEET. IN ADDITION...THERE WILL BE AN ENHANCED RISK
OF RIP CURRENTS DURING THIS TIME. THURSDAY NIGHT...THE COASTAL
TROUGH WILL CLOSE OFF AND BEGIN TO MOVE NORTHEAST UP THE COAST
ALLOWING THE PRESSURE GRADIENT TO RELAX. TRANSIENT HIGH PRESSURE
WILL PREVAIL FRIDAY BEFORE A WEAK COLD FRONT IMPACTS THE WATERS
SATURDAY NIGHT. AT THIS TIME...WINDS/SEAS ARE EXPECTED TO REMAIN
BELOW HEADLINE CRITERIA. ANOTHER STORM SYSTEM IS EXPECTED TO AFFECT
REGION EARLY NEXT WEEK.
&&
.TIDES/COASTAL FLOODING...
A COMBINATION OF ASTRONOMICAL HIGH TIDES AND LEFTOVER NORTHEAST
WINDS/SWELL WILL RESULT IN A THREAT FOR SHALLOW COASTAL FLOODING
NEAR THE TIME OF HIGH TIDE THURSDAY AND FRIDAY EVENING...PERHAPS
EXTENDING INTO THE SATURDAY EVENING HIGH TIDE.
&&
.CHS WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
SC...NONE.
MARINE...NONE.
&&
$$
ST/ECT
AREA FORECAST DISCUSSION
NWS CHARLESTON SC
1258 AM EDT TUE APR 14 2015
.SYNOPSIS...
THE REMNANTS OF A WARM FRONT WILL LIFT SLOWLY NORTH ACROSS THE
AREA TONIGHT. A COLD FRONT WILL APPROACH THE REGION TUESDAY...THEN
BACKDOOR ACROSS THE AREA LATE TUESDAY NIGHT. A WEDGE OF HIGH PRESSURE
WILL DEVELOP INTO LATE WEEK...BEFORE A WEAK COLD FRONT CROSSES THE
REGION LATE SATURDAY. HIGH PRESSURE WILL BRIEFLY RETURN SUNDAY WITH
ANOTHER STORM SYSTEM IMPACTING THE AREA EARLY NEXT WEEK.
&&
.NEAR TERM /UNTIL 6 AM THIS MORNING/...
14/04Z MESOANALYSIS PLACED WARM FRONTAL REMNANTS NORTH OF THE
FORECAST AREA--ROUGHLY KAIK-KOGB-KGGE. THIS BOUNDARY WILL CONTINUE
TO MEANDER NORTH WITH THE ENTIRE AREA EMBEDDED WITHIN A WARM/HUMID
AIRMASS. TEMPERATURES WILL FALL LITTLE OVERNIGHT...ONLY DROPPING
INTO THE UPPER 60S FOR MOST AREA. SCATTERED RAIN SHOWERS WILL
PERSIST IN THE WARM AIR ADVECTION REGIME...BUT COVERAGE SHOULD
DIMINISH THROUGH THE OVERNIGHT HOURS. ADJUSTED NEAR TERM POPS AND
TEMPERATURES TO MATCH CURRENT TRENDS.
&&
.SHORT TERM /6 AM THIS MORNING THROUGH THURSDAY/...
A DEEP PLUME OF MOISTURE FROM THE GULF OF MEXICO AND THE TROPICAL
PACIFIC WILL CONTINUE TO FEED INTO THE REGION FROM THE SOUTHWEST
DURING THIS PERIOD. MEANWHILE VARIOUS UPPER LEVEL DISTURBANCES WILL
MOVE THROUGH THE AREA AND RESULT IN HIGHER RAIN CHANCES AS THEY MOVE
THROUGH.
TUESDAY...THE FORECAST AREA WILL BE LOCATED SOLIDLY IN THE WARM
SECTOR WITH SOUTH TO SOUTHWEST WINDS HELPING TO BRING MID TO UPPER
60S DEWPOINTS INTO THE AREA. PRECIPITABLE WATER VALUES NEAR 1.9
INCHES IN THE MORNING WILL DROP SOME BY THE AFTERNOON AS MID AND
UPPER LEVEL MOISTURE ASSOCIATED WITH AN UPPER LEVEL DISTURBANCE
SHIFT AWAY FROM THE AREA. DESPITE WEAK SUBSIDENCE IN THE WAKE OF
THIS DISTURBANCE...STILL EXPECT THERE TO BE A DECENT CHANCE FOR
SHOWERS AND THUNDERSTORMS...ALTHOUGH CONFIDENCE IN POPS IS QUITE LOW
WITH THE 00Z ECMWF QUITE WET AND 12Z GFS AND CANADIAN QUITE
A BIT DRIER. NEW 12Z ECMWF CAME IN DRIER...SO WOULD NOT BE SURPRISED
IF RAIN CHANCES WOULD NEED TO BE LOWERED MORE THAN THE SLIGHT
DOWNWARD TREND THAT WAS INCORPORATED WITH THIS FORECAST PACKAGE.
THERE WILL BE DECENT INSTABILITY WITH LI/S FROM -3 TO -5 AND CAPE
VALUES FROM 800 TO 1200 J/KG...BUT WEAK SINKING MOTION AND
SOMEWHAT DRIER AIR IN THE MID AND UPPER LEVELS SHOULD KEEP THE
COVERAGE OF SHOWERS AND THUNDERSTORMS LOWER THAN WHAT IT COULD BE.
A FEW OF THE THUNDERSTORMS COULD BECOME STRONG...ESPECIALLY IF THE
WARMER HIGHS OF THE MAV GUIDANCE MATERIALIZE. ANY SLOW MOVING
THUNDERSTORMS COULD PRODUCE LOCALLY HEAVY RAINFALL. MADE A BIT OF
AN UPWARD ADJUSTMENTS TO HIGHS...MAINLY LOWER TO MID 80S...BUT
STILL QUITE A BIT BELOW THE VERY WARM MAV GUIDANCE.
TUESDAY NIGHT...WIDELY SCATTERED TO SCATTERED EVENING SHOWERS AND
THUNDERSTORMS...SOME WITH HEAVY RAINFALL SHOULD DIMINISH BY LATE
EVENING. A BACKDOOR COLD FRONT COULD BE PUSHING INTO FAR NORTHERN
AREAS LATE. IT WILL BE MILD WITH LOW TEMPERATURES MAINLY IN THE
MID 60S.
WEDNESDAY...THE BACKDOOR COLD FRONT WILL PUSH THROUGH MUCH OF
THE AREA AS A WEDGE OF SURFACE HIGH PRESSURE BEGINS TO WEDGE DOWN
EAST OF THE APPALACHIAN MOUNTAINS. CONTINUED DEEP LAYERED MOISTURE
IN COMBINATION WITH ENHANCED LOW LEVEL CONVERGENCE
WILL KEEP CHANCE/LIKELY POPS IN THE FORECAST. HIGHS SHOULD RANGE
FROM THE LOWER 70S NORTHWEST TO NEAR 80 NEAR THE ALTAMAHA IN
SOUTHEAST GEORGIA.
WEDNESDAY NIGHT INTO THURSDAY...THE HIGH PRESSURE WEDGE WILL
STRENGTHEN AS A COASTAL TROUGH DEVELOPS OFFSHORE. MODELS DEPICT THE
TROUGH CLOSING OFF INTO A SURFACE LOW AND EITHER REMAINING
STATIONARY FOR A TIME OR MOVING SLOWLY NORTH/NORTHEAST UP THE
COAST ON THURSDAY. BEST THREAT FOR RAIN WILL BE OVER/NEAR COASTAL
WATERS ON THURSDAY...CLOSER TO THE AREA OF LOW PRESSURE. COOL
NORTH/NORTHEAST FLOW AND OVERCAST SKIES WILL LIMIT HIGHS TO THE
UPPER 60S NORTHWEST TO UPPER 70S SOUTH.
&&
.LONG TERM /THURSDAY NIGHT THROUGH MONDAY/...
THE WEATHER PATTERN WILL CONTINUE TO BE UNSETTLED AND COMPLEX. ON
FRIDAY...A SURFACE LOW WILL BE POSITIONED OFF THE CAROLINA COAST AND
WILL LIFT NORTHEAST THROUGH THE DAY. ON SATURDAY...A WEAK BACKDOOR
COLD FRONT WILL CROSS THROUGH THE REGION WITH HIGH PRESSURE BUILDING
IN FROM THE NORTH BEHIND IT. THE HIGH WILL BE SHORT-LIVED AS THE
NEXT LOW PRESSURE SYSTEM DEVELOPS OVER THE SOUTHERN STATES LATE IN
THE WEEKEND. THERE ARE SOME MODEL DISCREPANCIES WITH DETAILS IN THE
LONG TERM...HOWEVER FAVORABLE MOISTURE AND A SERIES OF SHORTWAVES
WILL SUPPORT CHANCES FOR SHOWERS/THUNDERSTORMS MUCH OF THE PERIOD.
&&
.AVIATION /06Z TUESDAY THROUGH SATURDAY/...
KCHS...WARM FRONT NOW NORTH OF THE TERMINAL. WATCHING FOR A PERIOD
OF LOW CLOUDS OVER THE NEXT FEW HOURS...MAINLY 09-12Z. GUIDANCE
MIXED DURING THIS TIME...BUT GENERALLY FAVORS VFR. WITH AREA
OBSERVATIONS SHOWING SOME MVFR CIGS AROUND...WILL SHOW MVFR CIGS
09-12Z WITH A TEMPO VFR DURING THAT TIME. VFR FROM SUNRISE ON.
SCATTERED SHOWERS/TSTMS WILL LIKELY DEVELOP NORTHWEST OF THE
TERMINAL THIS AFTERNOON. CONFIDENCE TO LOW TO INCLUDE A MENTION
ATTM AND WILL BE REEVALUATED WITH THE 12Z TAF CYCLE.
KSAV...IFR CIGS ARE VERY NEAR THE TERMINAL...MAINLY TO THE NORTH.
THERE IS A SOLID CHANCE THESE CIGS WILL BUILD DOWN TO IMPACT THE
TERMINALS FOR A FEW HOURS PER RAP SOUNDINGS. WILL SHOW A TEMPO
GROUP FROM 08-10Z OF IFR BKN008 TO COVER THIS. OTHERWISE...EXPECT
VFR CONDITIONS TO PREVAIL. IF IFR CIGS TO DEVELOP...THEY MAY
LINGER LONGER THAN INDICATED...BUT THIS IS AGAINST THE GUIDANCE
MEAN. A CLUSTER OF SHOWERS/TSTMS DEVELOPING ALONG THE GULF SEA
BREEZE MAY APPROACH THE TERMINAL AFTER SUNSET. LOW CONFIDENCE
SHOWERS/TSTMS WILL REACH THAT FAR WITH DIMINISHING INSTABILITY
LATE AFTERNOON BEHIND THE ATLANTIC SEA BREEZE. WILL NOT INCLUDE A
MENTION ATTM AND WILL BE REEVALUATED WITH THE 12Z TAF CYCLE.
EXTENDED AVIATION OUTLOOK...FLIGHT RESTRICTIONS LIKELY AT TIMES
THROUGH THE WEEK AS PERIODIC SHOWERS AND T-STORMS IMPACT THE
TERMINALS.
&&
.MARINE...
TONIGHT...CONDITIONS WILL REMAIN BELOW SMALL CRAFT ADVISORY
THRESHOLDS AS A WARM FRONT SLOWLY LIFTS NORTH OF THE WATERS
OVERNIGHT. IN GENERAL...SOUTHERLY WINDS WILL REMAIN AT OR BELOW 15
KTS...HIGHEST AFTER MIDNIGHT. SEAS WILL RANGE BETWEEN 2-4
FT...HIGHEST IN OFFSHORE GEORGIA WATERS.
TUESDAY THROUGH SUNDAY...ON TUESDAY THE WATERS WILL BE HIGHLY
INFLUENCED BY ATLANTIC HIGH PRESSURE. A COLD FRONT IS EXPECTED TO
DESCEND SOUTH ACROSS THE WATERS LATE TUESDAY NIGHT INTO
WEDNESDAY...WITH A WEDGE OF HIGH PRESSURE DEVELOPING IN ITS WAKE. A
TIGHTENED PRESSURE GRADIENT AND SLIGHT PRESSURE RISES WILL RESULT AN
A NORTHEAST WIND SURGE LATE WEDNESDAY AND THURSDAY. SMALL CRAFT
ADVISORIES MAY EVENTUALLY BE NEEDED...ESPECIALLY FOR THE SOUTH
CAROLINA COASTAL WATERS...AS WINDS AND SEAS BUILD. IN
ADDITION...THERE LIKELY WILL BE AN ELEVATED RISK OF RIP CURRENTS
DURING DURING THE MID TO LATE WEEK TIME FRAME. ON THURSDAY...THE
INLAND WEDGE WILL STRENGTHEN AS A COASTAL TROUGH DEVELOPS AND CLOSES
OFF INTO A SURFACE LOW. THE LOW REMAINS STATIONARY FOR A TIME OR
MOVES NORTHEAST UP THE COAST THURSDAY INTO FRIDAY. SIGNIFICANT
UNCERTAINLY IN WIND DIRECTION AND SPEED DURING THIS PERIOD DUE TO
UNCERTAINTY OF SURFACE LOW POSITION...MOVEMENT AND STRENGTH. SEAS
WILL STILL REMAIN ELEVATED HOWEVER...EVEN IF THE WINDS DECREASE FOR
A TIME.
A COMBINATION OF ASTRONOMICAL HIGH TIDES AND THE LEFTOVER NORTHEAST
WINDS/SWELL...THERE IS A THREAT FOR SHALLOW COASTAL FLOODING NEAR
THE TIME OF HIGH TIDE FRIDAY EVENING...PERHAPS EXTENDING INTO THE
SATURDAY EVENING HIGH TIDE. GENERALLY MORE TRANQUIL CONDITIONS
EXPECTED THIS WEEKEND IN THE WAKE OF THE LOW PRESSURE AREA.
&&
.CHS WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
SC...NONE.
MARINE...NONE.
&&
$$
ST
AREA FORECAST DISCUSSION
NWS POCATELLO ID
1020 AM MDT TUE APR 14 2015
.SHORT TERM...TODAY THROUGH THURSDAY NIGHT. THE MORNING NAM AND
ASSOCIATED HI-RES MODELS WERE SHOWING THE DEVELOPMENT OF A SNAKE
RIVER CONVERGENCE EVENT FROM POCATELLO TO IDAHO FALLS TONIGHT. THUS
UPDATED GOING FORECAST TO INCREASE SNOWFALL AND PRECIP POTENTIAL
ALONG AND EAST OF THE I-15 CORRIDOR AND ISSUED A WINTER WEATHER
ADVISORY. SEE PREVIOUS DISCUSSION BELOW. HUSTON
MODELS BEGINNING TO COME TO SOME AGREEMENT ON SYSTEM TODAY THROUGH
WEDNESDAY WHICH WILL BRING WIND AND SNOW TO SOUTHEAST IDAHO.
LATEST 06Z NAM CLOSES OFF NEGATIVE TILT 500 MILLIBAR TROF OVER
SOUTHERN IDAHO LATE TONIGHT AND MOVES IT INTO SOUTHWEST WYOMING
THROUGH WEDNESDAY MORNING. THE 00Z GFS WAS IN DECENT AGREEMENT NOW
ALSO CLOSING OFF UPPER LOW IN SOUTHERN IDAHO AND MOVING INTO
SOUTHWEST WYOMING THROUGH WEDNESDAY MORNING. THE EUROPEAN REMAINS
MUCH FURTHER SOUTH WITH THE UPPER LOW IN CENTRAL UTAH BY WEDNESDAY
MORNING AND ALSO SLOWER WITH MOVEMENT. THE INITIAL PROBLEM WILL BE
STRONG WINDS WITH THE COLD FRONT MOVING QUICKLY THROUGH EASTERN
IDAHO LATER THIS MORNING THROUGH EARLY AFTERNOON. KEPT WIND
WARNINGS AND ADVISORIES IN PLACE WITH MODELS SHOWING SOME 35 MPH
SUSTAINED WINDS IN MAGIC VALLEY AND SNAKE PLAIN AND SOUTH CENTRAL
HIGHLANDS. EXPECT SNOW TO DEVELOP BEHIND THE COLD FRONT INITIALLY
IN CENTRAL MOUNTAINS THIS MORNING THEN FOCUSED ON THE SOUTHERN AND
EASTERN HIGHLANDS AND SNAKE RIVER PLAIN OVERNIGHT TONIGHT. FOR NOW
CONTINUED WITH 1 TO 3 INCHES IN CENTRAL MOUNTAINS AND SNAKE RIVER
PLAIN WITH 4 TO 8 INCHES EXPECTED IN IDAHO WASATCH AND CARIBOU
HIGHLANDS WHERE A WINTER WEATHER ADVISORY REMAINS IN EFFECT THIS
AFTERNOON THROUGH WEDNESDAY MORNING. THE COMBINATION OF SNOW AND
WINDS WILL LIKELY PRODUCE SOME DIFFICULT DRIVING CONDITIONS THIS
AFTERNOON AND ESPECIALLY OVERNIGHT TONIGHT ONCE THE SUN SETS.
TEMPERATURES WILL TURN SHARPLY COLDER THIS AFTERNOON BEHIND THE
COLD FRONT AND REMAIN WELL BELOW NORMAL WEDNESDAY. EXPECT DRY AND
SUNNY CONDITIONS THURSDAY WITH A RETURN TO SEASONABLE TEMPERATURES.
GK
.LONG TERM...FRIDAY THROUGH NEXT MONDAY. MODELS CONSISTENT IN
DEVELOPING UPPER RIDGING INTO PAC NW THURSDAY NIGHT AS CUTOFF LOW
DROPS TO THE FOUR CORNERS AREA. A QUICK MOVING DISTURBANCE WILL
CROSS NORTHERN IDAHO AND MONTANA SATURDAY WITH LIMITED SHOWER
ACTIVITY IN THE UPPER SNAKE HIGHLANDS. THE MAIN CHANGE TO THE
FORECAST IS SATURDAY NIGHT AND SUNDAY WHERE THE SHARP RIDGE AXIS
CLOSE TO THE COAST RESULTS IN MORE NORTHERLY FLOW ALONG THE WYOMING
BORDER AND THUS SOME RISK OF LIGHT SHOWERS IN THE EASTERN HIGHLANDS.
RS
&&
.AVIATION....MOST NOTABLY FOR PIH AND IDA. KSFX RADAR VAD WINDS
SHOWS SOUTH WINDS 40-50 KTS CLOSE TO 2000 FEET OFF THE SURFACE AHEAD
OF A STRONG COLD FRONT. THE NAM12 AND HRRR MODELS HAVE THE TIGHT
SURFACE PRESSURE GRADIENT OVER MALAD AND BEAR LAKE AREA SHIFTING
EAST BY 12Z THIS MORNING. THAT WOULD FAVOR THE CURRENT THREAT OF
LLWS ENDING 1 TO 2 HOURS AHEAD OF THE CURRENT TAF TIMING. PASSAGE OF
THE FRONT AT KPIH SHOULD BE NEAR 14Z. VERY IMPRESSIVE SURFACE POST
FRONTAL PRESSURE GRADIENT TODAY. HIGH WIND WARNING IN EFFECT FROM
NOON TO 15/04Z. ALL 3 SNAKE PLAIN TAF SITES ARE INCLUDED. SNOW
LEVELS FALL TO VALLEY FLOORS OVERNIGHT WHICH BRINGS SNOW SHOWERS
WITH MVFR CEILINGS AT KIDA AND KPIH 15/04-09Z.
&&
.PIH WATCHES/WARNINGS/ADVISORIES...
HIGH WIND WARNING FROM NOON TODAY TO 10 PM MDT THIS EVENING
IDZ017-021-022.
WIND ADVISORY FROM NOON TODAY TO 10 PM MDT THIS EVENING IDZ020.
WINTER WEATHER ADVISORY FROM 6 PM THIS EVENING TO NOON MDT
WEDNESDAY ABOVE 5500 FEET FOR THE IDZ023-025.
WINTER WEATHER ADVISORY FROM 6 PM THIS EVENING TO 4 AM WEDNESDAY
MORNING IDZ020-021.
&&
$$
AREA FORECAST DISCUSSION
NWS POCATELLO ID
338 AM MDT TUE APR 14 2015
.SHORT TERM...TODAY THROUGH THURSDAY NIGHT.
MODELS BEGINNING TO COME TO SOME AGREEMENT ON SYSTEM TODAY THROUGH
WEDNESDAY WHICH WILL BRING WIND AND SNOW TO SOUTHEAST IDAHO.
LATEST 06Z NAM CLOSES OFF NEGATIVE TILT 500 MILLIBAR TROF OVER
SOUTHERN IDAHO LATE TONIGHT AND MOVES IT INTO SOUTHWEST WYOMING
THROUGH WEDNESDAY MORNING. THE 00Z GFS WAS IN DECENT AGREEMENT NOW
ALSO CLOSING OFF UPPER LOW IN SOUTHERN IDAHO AND MOVING INTO
SOUTHWEST WYOMING THROUGH WEDNESDAY MORNING. THE EUROPEAN REMAINS
MUCH FURTHER SOUTH WITH THE UPPER LOW IN CENTRAL UTAH BY WEDNESDAY
MORNING AND ALSO SLOWER WITH MOVEMENT. THE INITIAL PROBLEM WILL BE
STRONG WINDS WITH THE COLD FRONT MOVING QUICKLY THROUGH EASTERN
IDAHO LATER THIS MORNING THROUGH EARLY AFTERNOON. KEPT WIND
WARNINGS AND ADVISORIES IN PLACE WITH MODELS SHOWING SOME 35 MPH
SUSTAINED WINDS IN MAGIC VALLEY AND SNAKE PLAIN AND SOUTH CENTRAL
HIGHLANDS. EXPECT SNOW TO DEVELOP BEHIND THE COLD FRONT INITIALLY
IN CENTRAL MOUNTAINS THIS MORNING THEN FOCUSED ON THE SOUTHERN AND
EASTERN HIGHLANDS AND SNAKE RIVER PLAIN OVERNIGHT TONIGHT. FOR NOW
CONTINUED WITH 1 TO 3 INCHES IN CENTRAL MOUNTAINS AND SNAKE RIVER
PLAIN WITH 4 TO 8 INCHES EXPECTED IN IDAHO WASATCH AND CARIBOU
HIGHLANDS WHERE A WINTER WEATHER ADVISORY REMAINS IN EFFECT THIS
AFTERNOON THROUGH WEDNESDAY MORNING. THE COMBINATION OF SNOW AND
WINDS WILL LIKELY PRODUCE SOME DIFFICULT DRIVING CONDITIONS THIS
AFTERNOON AND ESPECIALLY OVERNIGHT TONIGHT ONCE THE SUN SETS.
TEMPERATURES WILL TURN SHARPLY COLDER THIS AFTERNOON BEHIND THE
COLD FRONT AND REMAIN WELL BELOW NORMAL WEDNESDAY. EXPECT DRY AND
SUNNY CONDITIONS THURSDAY WITH A RETURN TO SEASONABLE
TEMPERATURES.
GK
.LONG TERM...FRIDAY THROUGH NEXT MONDAY. MODELS CONSISTENT IN
DEVELOPING UPPER RIDGING INTO PAC NW THURSDAY NIGHT AS CUTOFF LOW
DROPS TO THE FOUR CORNERS AREA. A QUICK MOVING DISTURBANCE WILL
CROSS NORTHERN IDAHO AND MONTANA SATURDAY WITH LIMITED SHOWER
ACTIVITY IN THE UPPER SNAKE HIGHLANDS. THE MAIN CHANGE TO THE
FORECAST IS SATURDAY NIGHT AND SUNDAY WHERE THE SHARP RIDGE AXIS
CLOSE TO THE COAST RESULTS IN MORE NORTHERLY FLOW ALONG THE WYOMING
BORDER AND THUS SOME RISK OF LIGHT SHOWERS IN THE EASTERN HIGHLANDS. RS
&&
.AVIATION....MOST NOTABLY FOR PIH AND IDA. KSFX RADAR VAD WINDS
SHOWS SOUTH WINDS 40-50 KTS CLOSE TO 2000 FEET OFF THE SURFACE AHEAD
OF A STRONG COLD FRONT. THE NAM12 AND HRRR MODELS HAVE THE TIGHT
SURFACE PRESSURE GRADIENT OVER MALAD AND BEAR LAKE AREA SHIFTING
EAST BY 12Z THIS MORNING. THAT WOULD FAVOR THE CURRENT THREAT OF
LLWS ENDING 1 TO 2 HOURS AHEAD OF THE CURRENT TAF TIMING. PASSAGE OF
THE FRONT AT KPIH SHOULD BE NEAR 14Z. VERY IMPRESSIVE SURFACE POST
FRONTAL PRESSURE GRADIENT TODAY. HIGH WIND WARNING IN EFFECT FROM
NOON TO 15/04Z. ALL 3 SNAKE PLAIN TAF SITES ARE INCLUDED. SNOW
LEVELS FALL TO VALLEY FLOORS OVERNIGHT WHICH BRINGS SNOW SHOWERS
WITH MVFR CEILINGS AT KIDA AND KPIH 15/04-09Z.
&&
.PIH WATCHES/WARNINGS/ADVISORIES...
HIGH WIND WARNING FROM NOON TODAY TO 10 PM MDT THIS EVENING
IDZ017-021-022.
WIND ADVISORY FROM NOON TODAY TO 10 PM MDT THIS EVENING IDZ020.
WINTER WEATHER ADVISORY FROM 6 PM THIS EVENING TO NOON MDT
WEDNESDAY ABOVE 5500 FEET FOR THE IDZ023-025.
&&
$$
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
1001 PM CDT WED APR 15 2015
.UPDATE...
758 PM CDT
HAVE ONLY MADE SLIGHT ADJUSTMENTS TO THE REST OF TONIGHT FORECAST.
A PICTURESQUE SKY OF VIRGA FROM CIRRUS/HIGH BASED ALTOCU OUT OUR
WINDOW AT SUNDOWN AND SHARED WITH US BY SEVERAL OF OUR SOCIAL
MEDIA FOLLOWERS. THE RAOB FROM DVN AT 00Z INDICATES A WARM
ADVECTION PROFILE FROM JUST OFF THE DECK ALL THE WAY UP...WITH
MOISTENING OCCURRING 15000 FT AND ABOVE ALONG WITH SOME MODEST
LAPSE RATES...THOUGH VERY DRY STILL BELOW THAT. AT ILX THIS
SATURATED LAYER IS DOWN TO 6000 FT WITH PRONOUNCED DRYING BELOW.
WATER VAPOR IMAGERY INDICATES A COMPACT BUT MOISTURE-STARVED
CIRCULATION IN SOUTHWEST ILLINOIS ADVANCING NORTHEAST...WITH SOME
SHOWER ACTIVITY REACHING THE GROUND AHEAD OF IT IN THE CENTRALIA
AND EFFINGHAM AREAS. TIMING THIS CORRIDOR OF FORCING WOULD MOVE
IT INTO THE SOUTHERN FORECAST AREA AROUND 11 PM. RAP AND NAM
FORECASTS INDICATE MOVE VEERED/SOUTHERLY PROFILES DOWN TO
900MB...WITH FORECAST MOISTURE TRANSPORT AND ADIABATIC LIFT
LIKELY TO AID IN SATURATION FOR AT LEAST SCATTERED LIGHT SHOWERS
ACROSS THE EASTERN FORECAST AREA. THAT IS IN LINE WITH GOING
FORECAST AND FOR THE MOST PART CURRENT HIGH-RES GUIDANCE. JUST
HAVE SLOWED THE START TIME OF POPS DOWN SLIGHTLY...BUT ALL IN ALL
A NEGLIGIBLE CHANGE TO WORDING FOR MOST AREAS. RAINFALL AMOUNTS
UNDER 0.15 OF AN INCH LOOK GOOD...WITH MOST OF NORTH CENTRAL
ILLINOIS NOT SEEING MORE THAN A TRACE.
GOING TEMPERATURES AND IMPROVING RELATIVE HUMIDITY VALUES LOOK ON
TRACK.
MTF
&&
.SHORT TERM...
339 PM CDT
THROUGH FRIDAY...
BETTER AGREEMENT BETWEEN DETERMINISTIC MODELS AND THEIR ENSEMBLE
COUNTERPARTS IS PROVIDING INCREASED FORECAST CONFIDENCE FOR THE
REMAINDER OF THE WEEK AND INTO EARLY NEXT WEEK. THE PRIMARY UPPER
LEVEL FEATURES BEING TRACKED INCLUDE A LARGE SOUTHERN STREAM LOW
DIGGING INTO THE FOUR CORNERS...A DOWNSTREAM RIDGE WITH EMBEDDED
SHORTWAVES...AND A CLOSED LOW PROJECTED TO DEVELOP IN A DEEPENING
NORTHERN STREAM TROUGH AND MERGE LATE IN THE WEEKEND WITH THE SYSTEM
THAT FINALLY WILL BE LIFTING OUT OF THE DESERT SOUTHWEST. AT LOWER
LEVELS...MODELS AGREE IN LIFTING A WEAK SURFACE TROUGH ACROSS THE
AREA TONIGHT AND IN TAKING A MORE DEVELOPED LOW PRESSURE SYSTEM
ACROSS THE AREA SATURDAY NIGHT INTO SUNDAY IN CONJUNCTION WITH THE
MERGING UPPER TROUGHS.
FOR THIS EVENING AND OVERNIGHT...THE AREA OF SHOWERS AND ISOLATED
TSRA STRETCHING FROM NORTHWEST IA ACROSS MO AND INTO KY IS
CORRELATED WITH A GRADIENT OF ENHANCED MOISTURE FLUX DEPICTED IN THE
RAP. AS THIS GRADIENT LIFTS NORTH...PRECIP CHANCES INCREASE TOWARD
MIDNIGHT AND ESPECIALLY IN THE PREDAWN HOURS. FORECAST SOUNDINGS
TREND TOWARD MOIST ADIABATIC AND DEEPLY SATURATED...SO PWATS
INCREASE CONSIDERABLY OVERNIGHT BUT INSTABILITY IS TALL AND SKINNY.
BETTER CHANCE OF TSRA WILL LIKELY REMAIN SOUTH AND EAST OF THE METRO
AREA.
DURING THE DAYTIME THURSDAY AND ESPECIALLY INTO THURSDAY
NIGHT...HEIGHTS INCREASE ALOFT AS THE UPPER SHORTWAVES MOVE EAST OF
THE AREA AND LOWER LEVELS DRY OUT. WILL CARRY LOW CHANCE POPS INTO
THE THURSDAY MORNING HOURS AND EARLY AFTERNOON BUT KEEP THURSDAY
NIGHT AND FRIDAY DRY.
LENNING
&&
.LONG TERM...
339 PM CDT
FRIDAY NIGHT THROUGH WEDNESDAY...
AFTER ANOTHER QUIET DAY ON SATURDAY...THE MERGING NORTHERN AND
SOUTHERN STREAM TROUGHS AND DEVELOPMENT OF A CLOSED SURFACE LOW IN
THE LEE OF THE ROCKIES WILL BRING INCREASED PRECIP CHANCES TO THE
AREA FOR SATURDAY NIGHT AND SUNDAY. WITH THE CENTER OF THE SURFACE
LOW PASSING SOUTH OF THE AREA ACROSS CENTRAL ILLINOIS...AM SEEING
GOOD SUPPORT FOR SHOWERS SATURDAY NIGHT AND EARLY SUNDAY BUT NOT
MUCH IN THE WAY OF CONVECTION UNTIL THE LOW PUSHES A WARM FRONT
THROUGH THE AREA AROUND MIDDAY AND BRIEFLY MOVES THE AREA INTO
THE WARM SECTOR AHEAD OF THE TRAILING COLD FRONT. THE PEAK PERIOD
FOR TSRA WOULD APPEAR TO BE SUNDAY AFTERNOON AND EVENING.
AFTER THE SURFACE LOW LIFTS WELL NORTH OF THE AREA SUNDAY NIGHT
INTO MONDAY...CYCLONIC FLOW ALOFT AND RESIDUAL BOUNDARY LAYER
MOISTURE MAY CONTINUE TO SUPPORT THE CHANCE OF SHOWERS INTO
MONDAY...BUT A RIDGE OF HIGH PRESSURE WILL BEGIN TO BUILD FROM THE
PLAINS INTO THE SOUTHERN GREAT LAKES BY TUESDAY...AGAIN DRYING
THINGS OUT FOR AT LEAST THE FIRST HALF OF THE WEEK.
LENNING
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 03Z...
* EAST-NORTHEAST WINDS 10-15 KT THIS EVENING GRADUALLY DIMINISHING
OVERNIGHT.
* POTENTIAL FOR SHOWERS TONIGHT/EARLY THURSDAY MORNING.
* LOWERING VFR CEILINGS BY LATE EVENING...A PERIOD OF MVFR/IFR
LIKELY EARLY THURSDAY.
* NORTHEAST WINDS 10 KT OR LESS THURSDAY.
RATZER
//DISCUSSION...UPDATED 00Z...
EAST-NORTHEAST WINDS PERSIST ACROSS THE TERMINALS EARLY THIS
EVENING AS FORECAST AREA REMAINS BETWEEN HIGH PRESSURE TO THE
NORTHEAST OF THE LAKES AND A WEAK AREA OF LOW PRESSURE OVER THE
LOWER MISSISSIPPI VALLEY. WINDS HAVE LOST SOME OF THEIR HIGHER
GUSTS WITH THE LOWERING SUN ANGLE AND INCREASING CLOUD COVER
ALLOWING BOUNDARY LAYER TO COOL A BIT...THOUGH SPEEDS 10-15 KT
SHOULD PERSIST INTO THIS EVENING BEFORE THE GRADIENT WEAKENS
SLOWLY OVERNIGHT.
THE EAST-NORTHEAST LOW LEVEL FLOW WAS MAINTAINING ADVECTION OF DRY
LOW LEVEL AIR ACROSS THE REGION...WHILE SOUTH-SOUTHEAST WINDS
ALOFT WERE PULLING MOISTURE NORTHWARD ALOFT AS THE SURFACE LOW
OVER THE LOWER MISSISSIPPI VALLEY MOVES SLOWLY NORTHEAST. VFR
CEILINGS WILL THICKEN AND LOWER THROUGH LATE EVENING WITH A FEW
SPOTTY SHOWERS LIKELY STRUGGLING TO PRODUCE PRECIP THROUGH THE DRY
LAYER CLOSER TO THE SURFACE...BUT EVENTUALLY SHOWERS SHOULD MOVE
INTO THE AREA WITH THE BEST MOISTURE TRANSPORT FOCUSED ACROSS
NORTHEAST IL/NORTHWEST INDIANA 09-13Z THURSDAY MORNING BEFORE
SHIFTING EAST. SOME WEAK ELEVATED INSTABILITY IS NOTED IN FORECAST
SOUNDINGS...WITH THE POTENTIAL FOR ISOLATED TSRA...THOUGH COVERAGE
IS EXPECTED TO BE TOO LOW TO INCLUDE IN TAFS. BETTER COVERAGE
PERHAPS FARTHER SOUTH ALONG THE IL/IN STATE LINE. THE BEST FORCING
AND MOISTURE FEED REMAINS GENERALLY EAST OF KRFD...WITH LOWEST
CHANCES OF RAIN AND LOWER CEILINGS THERE. WITH THE ARRIVAL OF
SHOWERS OVER THE EASTERN TERMINALS...FORECAST SOUNDINGS AND
STATISTICAL GUIDANCE DOES INDICATE A PERIOD OF MVFR...POSSIBLY
IFR EARLY THURSDAY MORNING. LIGHT WINDS BY THAT TIME SUGGEST MVFR
CIGS MAY BE A LITTLE SLOW TO LIFT/SCATTER DURING THE
MORNING/MIDDAY.
WEAK GRADIENT AND LIGHT WINDS THURSDAY ARE EXPECTED TO BECOME
NORTHEAST NEAR LAKE MICHIGAN...WHILE INLAND SITES DPA AND RFD ARE
LIKELY SEE LIGHT NORTH-NORTHWEST WINDS.
RATZER
//ORD AND MDW CONFIDENCE...UPDATED 03Z...
* HIGH CONFIDENCE IN WIND/CLOUD TRENDS THROUGH THIS EVENING.
* MEDIUM CONFIDENCE IN SHRA COVERAGE/TIMING OVERNIGHT AND EARLY
THURSDAY. MEDIUM-HIGH CONFIDENCE IN PERIOD OF MVFR
CIGS...MEDIUM IN IFR.
* MEDIUM CONFIDENCE IN LIGHT WIND DIRECTION DETAILS THURSDAY.
* HIGH CONFIDENCE ANY TSRA WILL BE ISOLATED/LOW COVERAGE.
RATZER
//OUTLOOK FOR ORD/MDW FOR 12Z FRIDAY-12Z WEDNESDAY...UPDATED 00Z...
FRIDAY...VFR. LIGHT VARIABLE WINDS BECOMING SOUTHEAST.
SATURDAY...VFR. CHANCE OF SHRA WITH MVFR POSSIBLE SATURDAY NIGHT.
NORTHEAST WINDS.
SUNDAY...CHANCE SHRA. MVFR POSSIBLE. EAST-NORTHEAST WINDS.
MONDAY...CHANCE SHRA EARLY. MVFR IMPROVING TO VFR. WEST-NORTHWEST
WINDS.
TUESDAY...VFR. CHANCE SHRA TUES NGT. WEST WINDS.
RATZER
&&
.MARINE...
153 PM CDT
A RIDGE OF HIGH PRESSURE CENTERED JUST TO THE NORTHEAST OF THE
GREAT LAKES IS ALLOWING FOR LIGHTER WINDS ACROSS THE LAKE
TODAY...BUT WITH THE HIGHEST WINDS OF 10 TO 20 KT BEING OBSERVED
OVER THE SOUTHERN HALF. EASTERLY WINDS OF 10 TO 20 KT WILL
CONTINUE TONIGHT FOR THE SOUTH HALF AND THE NEARSHORE AS A TIGHTER
PRESSURE GRADIENT REMAINS...AND WITH MORE STABLE CONDITIONS
HELPING TO KEEP WIND SPEEDS DOWN. SURFACE PATTERN BEGINS TO RELAX
LATER TONIGHT INTO THURSDAY MORNING WHILE SPEEDS DIMINISH AND WITH
WINDS LIKELY BECOMING VARIABLE DURING THE DAY THURSDAY. THIS
RELAXED PATTERN LOOKS TO PERSIST THROUGH THE END OF THE WORK
WEEK...WITH GENERALLY LIGHTER SPEEDS IN PLACE.
RODRIGUEZ
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...NONE.
&&
$$
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AREA FORECAST DISCUSSION...CORRECTED
NWS CHICAGO/ROMEOVILLE IL
800 PM CDT WED APR 15 2015
.UPDATE...
758 PM CDT
HAVE ONLY MADE SLIGHT ADJUSTMENTS TO THE REST OF TONIGHT FORECAST.
A PICTURESQUE SKY OF VIRGA FROM CIRRUS/HIGH BASED ALTOCU OUT OUR
WINDOW AT SUNDOWN AND SHARED WITH US BY SEVERAL OF OUR SOCIAL
MEDIA FOLLOWERS. THE RAOB FROM DVN AT 00Z INDICATES A WARM
ADVECTION PROFILE FROM JUST OFF THE DECK ALL THE WAY UP...WITH
MOISTENING OCCURRING 15000 FT AND ABOVE ALONG WITH SOME MODEST
LAPSE RATES...THOUGH VERY DRY STILL BELOW THAT. AT ILX THIS
SATURATED LAYER IS DOWN TO 6000 FT WITH PRONOUNCED DRYING BELOW.
WATER VAPOR IMAGERY INDICATES A COMPACT BUT MOISTURE-STARVED
CIRCULATION IN SOUTHWEST ILLINOIS ADVANCING NORTHEAST...WITH SOME
SHOWER ACTIVITY REACHING THE GROUND AHEAD OF IT IN THE CENTRALIA
AND EFFINGHAM AREAS. TIMING THIS CORRIDOR OF FORCING WOULD MOVE
IT INTO THE SOUTHERN FORECAST AREA AROUND 11 PM. RAP AND NAM
FORECASTS INDICATE MOVE VEERED/SOUTHERLY PROFILES DOWN TO
900MB...WITH FORECAST MOISTURE TRANSPORT AND ADIABATIC LIFT
LIKELY TO AID IN SATURATION FOR AT LEAST SCATTERED LIGHT SHOWERS
ACROSS THE EASTERN FORECAST AREA. THAT IS IN LINE WITH GOING
FORECAST AND FOR THE MOST PART CURRENT HIGH-RES GUIDANCE. JUST
HAVE SLOWED THE START TIME OF POPS DOWN SLIGHTLY...BUT ALL IN ALL
A NEGLIGIBLE CHANGE TO WORDING FOR MOST AREAS. RAINFALL AMOUNTS
UNDER 0.15 OF AN INCH LOOK GOOD...WITH MOST OF NORTH CENTRAL
ILLINOIS NOT SEEING MORE THAN A TRACE.
GOING TEMPERATURES AND IMPROVING RELATIVE HUMIDITY VALUES LOOK ON
TRACK.
MTF
&&
.SHORT TERM...
339 PM CDT
THROUGH FRIDAY...
BETTER AGREEMENT BETWEEN DETERMINISTIC MODELS AND THEIR ENSEMBLE
COUNTERPARTS IS PROVIDING INCREASED FORECAST CONFIDENCE FOR THE
REMAINDER OF THE WEEK AND INTO EARLY NEXT WEEK. THE PRIMARY UPPER
LEVEL FEATURES BEING TRACKED INCLUDE A LARGE SOUTHERN STREAM LOW
DIGGING INTO THE FOUR CORNERS...A DOWNSTREAM RIDGE WITH EMBEDDED
SHORTWAVES...AND A CLOSED LOW PROJECTED TO DEVELOP IN A DEEPENING
NORTHERN STREAM TROUGH AND MERGE LATE IN THE WEEKEND WITH THE SYSTEM
THAT FINALLY WILL BE LIFTING OUT OF THE DESERT SOUTHWEST. AT LOWER
LEVELS...MODELS AGREE IN LIFTING A WEAK SURFACE TROUGH ACROSS THE
AREA TONIGHT AND IN TAKING A MORE DEVELOPED LOW PRESSURE SYSTEM
ACROSS THE AREA SATURDAY NIGHT INTO SUNDAY IN CONJUNCTION WITH THE
MERGING UPPER TROUGHS.
FOR THIS EVENING AND OVERNIGHT...THE AREA OF SHOWERS AND ISOLATED
TSRA STRETCHING FROM NORTHWEST IA ACROSS MO AND INTO KY IS
CORRELATED WITH A GRADIENT OF ENHANCED MOISTURE FLUX DEPICTED IN THE
RAP. AS THIS GRADIENT LIFTS NORTH...PRECIP CHANCES INCREASE TOWARD
MIDNIGHT AND ESPECIALLY IN THE PREDAWN HOURS. FORECAST SOUNDINGS
TREND TOWARD MOIST ADIABATIC AND DEEPLY SATURATED...SO PWATS
INCREASE CONSIDERABLY OVERNIGHT BUT INSTABILITY IS TALL AND SKINNY.
BETTER CHANCE OF TSRA WILL LIKELY REMAIN SOUTH AND EAST OF THE METRO
AREA.
DURING THE DAYTIME THURSDAY AND ESPECIALLY INTO THURSDAY
NIGHT...HEIGHTS INCREASE ALOFT AS THE UPPER SHORTWAVES MOVE EAST OF
THE AREA AND LOWER LEVELS DRY OUT. WILL CARRY LOW CHANCE POPS INTO
THE THURSDAY MORNING HOURS AND EARLY AFTERNOON BUT KEEP THURSDAY
NIGHT AND FRIDAY DRY.
LENNING
&&
.LONG TERM...
339 PM CDT
FRIDAY NIGHT THROUGH WEDNESDAY...
AFTER ANOTHER QUIET DAY ON SATURDAY...THE MERGING NORTHERN AND
SOUTHERN STREAM TROUGHS AND DEVELOPMENT OF A CLOSED SURFACE LOW IN
THE LEE OF THE ROCKIES WILL BRING INCREASED PRECIP CHANCES TO THE
AREA FOR SATURDAY NIGHT AND SUNDAY. WITH THE CENTER OF THE SURFACE
LOW PASSING SOUTH OF THE AREA ACROSS CENTRAL ILLINOIS...AM SEEING
GOOD SUPPORT FOR SHOWERS SATURDAY NIGHT AND EARLY SUNDAY BUT NOT
MUCH IN THE WAY OF CONVECTION UNTIL THE LOW PUSHES A WARM FRONT
THROUGH THE AREA AROUND MIDDAY AND BRIEFLY MOVES THE AREA INTO
THE WARM SECTOR AHEAD OF THE TRAILING COLD FRONT. THE PEAK PERIOD
FOR TSRA WOULD APPEAR TO BE SUNDAY AFTERNOON AND EVENING.
AFTER THE SURFACE LOW LIFTS WELL NORTH OF THE AREA SUNDAY NIGHT
INTO MONDAY...CYCLONIC FLOW ALOFT AND RESIDUAL BOUNDARY LAYER
MOISTURE MAY CONTINUE TO SUPPORT THE CHANCE OF SHOWERS INTO
MONDAY...BUT A RIDGE OF HIGH PRESSURE WILL BEGIN TO BUILD FROM THE
PLAINS INTO THE SOUTHERN GREAT LAKES BY TUESDAY...AGAIN DRYING
THINGS OUT FOR AT LEAST THE FIRST HALF OF THE WEEK.
LENNING
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 00Z...
* EAST-NORTHEAST WINDS 10-15 KT THIS EVENING GRADUALLY DIMINISHING
OVERNIGHT.
* POTENTIAL FOR SHOWERS TONIGHT/EARLY THURSDAY MORNING.
* LOWERING VFR CEILINGS BY LATE EVENING...A PERIOD OF MVFR/IFR
LIKELY EARLY THURSDAY.
* NORTHEAST WINDS 10 KT OR LESS THURSDAY.
RATZER
//DISCUSSION...UPDATED 00Z...
EAST-NORTHEAST WINDS PERSIST ACROSS THE TERMINALS EARLY THIS
EVENING AS FORECAST AREA REMAINS BETWEEN HIGH PRESSURE TO THE
NORTHEAST OF THE LAKES AND A WEAK AREA OF LOW PRESSURE OVER THE
LOWER MISSISSIPPI VALLEY. WINDS HAVE LOST SOME OF THEIR HIGHER
GUSTS WITH THE LOWERING SUN ANGLE AND INCREASING CLOUD COVER
ALLOWING BOUNDARY LAYER TO COOL A BIT...THOUGH SPEEDS 10-15 KT
SHOULD PERSIST INTO THIS EVENING BEFORE THE GRADIENT WEAKENS
SLOWLY OVERNIGHT.
THE EAST-NORTHEAST LOW LEVEL FLOW WAS MAINTAINING ADVECTION OF DRY
LOW LEVEL AIR ACROSS THE REGION...WHILE SOUTH-SOUTHEAST WINDS
ALOFT WERE PULLING MOISTURE NORTHWARD ALOFT AS THE SURFACE LOW
OVER THE LOWER MISSISSIPPI VALLEY MOVES SLOWLY NORTHEAST. VFR
CEILINGS WILL THICKEN AND LOWER THROUGH LATE EVENING WITH A FEW
SPOTTY SHOWERS LIKELY STRUGGLING TO PRODUCE PRECIP THROUGH THE DRY
LAYER CLOSER TO THE SURFACE...BUT EVENTUALLY SHOWERS SHOULD MOVE
INTO THE AREA WITH THE BEST MOISTURE TRANSPORT FOCUSED ACROSS
NORTHEAST IL/NORTHWEST INDIANA 09-13Z THURSDAY MORNING BEFORE
SHIFTING EAST. SOME WEAK ELEVATED INSTABILITY IS NOTED IN FORECAST
SOUNDINGS...WITH THE POTENTIAL FOR ISOLATED TSRA...THOUGH COVERAGE
IS EXPECTED TO BE TOO LOW TO INCLUDE IN TAFS. BETTER COVERAGE
PERHAPS FARTHER SOUTH ALONG THE IL/IN STATE LINE. THE BEST FORCING
AND MOISTURE FEED REMAINS GENERALLY EAST OF KRFD...WITH LOWEST
CHANCES OF RAIN AND LOWER CEILINGS THERE. WITH THE ARRIVAL OF
SHOWERS OVER THE EASTERN TERMINALS...FORECAST SOUNDINGS AND
STATISTICAL GUIDANCE DOES INDICATE A PERIOD OF MVFR...POSSIBLY
IFR EARLY THURSDAY MORNING. LIGHT WINDS BY THAT TIME SUGGEST MVFR
CIGS MAY BE A LITTLE SLOW TO LIFT/SCATTER DURING THE
MORNING/MIDDAY.
WEAK GRADIENT AND LIGHT WINDS THURSDAY ARE EXPECTED TO BECOME
NORTHEAST NEAR LAKE MICHIGAN...WHILE INLAND SITES DPA AND RFD ARE
LIKELY SEE LIGHT NORTH-NORTHWEST WINDS.
RATZER
//ORD AND MDW CONFIDENCE...UPDATED 00Z...
* HIGH CONFIDENCE IN WIND/CLOUD TRENDS THROUGH THIS EVENING.
* MEDIUM CONFIDENCE IN SHRA COVERAGE/TIMING OVERNIGHT AND EARLY
THURSDAY. MEDIUM-HIGH CONFIDENCE IN PERIOD OF MVFR
CIGS...MEDIUM IN IFR.
* MEDIUM CONFIDENCE IN LIGHT WIND DIRECTION DETAILS THURSDAY.
* HIGH CONFIDENCE ANY TSRA WILL BE ISOLATED/LOW COVERAGE.
RATZER
//OUTLOOK FOR ORD/MDW FOR 12Z FRIDAY-12Z WEDNESDAY...UPDATED 00Z...
FRIDAY...VFR. LIGHT VARIABLE WINDS BECOMING SOUTHEAST.
SATURDAY...VFR. CHANCE OF SHRA WITH MVFR POSSIBLE SATURDAY NIGHT.
NORTHEAST WINDS.
SUNDAY...CHANCE SHRA. MVFR POSSIBLE. EAST-NORTHEAST WINDS.
MONDAY...CHANCE SHRA EARLY. MVFR IMPROVING TO VFR. WEST-NORTHWEST
WINDS.
TUESDAY...VFR. CHANCE SHRA TUES NGT. WEST WINDS.
RATZER
&&
.MARINE...
153 PM CDT
A RIDGE OF HIGH PRESSURE CENTERED JUST TO THE NORTHEAST OF THE
GREAT LAKES IS ALLOWING FOR LIGHTER WINDS ACROSS THE LAKE
TODAY...BUT WITH THE HIGHEST WINDS OF 10 TO 20 KT BEING OBSERVED
OVER THE SOUTHERN HALF. EASTERLY WINDS OF 10 TO 20 KT WILL
CONTINUE TONIGHT FOR THE SOUTH HALF AND THE NEARSHORE AS A TIGHTER
PRESSURE GRADIENT REMAINS...AND WITH MORE STABLE CONDITIONS
HELPING TO KEEP WIND SPEEDS DOWN. SURFACE PATTERN BEGINS TO RELAX
LATER TONIGHT INTO THURSDAY MORNING WHILE SPEEDS DIMINISH AND WITH
WINDS LIKELY BECOMING VARIABLE DURING THE DAY THURSDAY. THIS
RELAXED PATTERN LOOKS TO PERSIST THROUGH THE END OF THE WORK
WEEK...WITH GENERALLY LIGHTER SPEEDS IN PLACE.
RODRIGUEZ
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...NONE.
&&
$$
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AREA FORECAST DISCUSSION
NWS JACKSON KY
942 PM EDT WED APR 15 2015
.UPDATE...
ISSUED AT 941 PM EDT WED APR 15 2015
GENERALLY ISOLATED SHOWERS CONTINUE ACROSS THE CWA LATE THIS
EVENING..WITH MORE SCATTERED ACTIVITY ACROSS THE NORTH CENTRAL
PORTION OF THE STATE ALONG A WEAK BOUNDARY. HEAVIER SHOWERS AND
THUNDERSTORMS REMAIN WELL TO OUR SOUTHWEST ACROSS WESTERN
TN...CLOSER TO THE SURFACE LOW PRESSURE CENTER LOCATED NEAR THE
SAME AREA. THIS LOW WILL CONTINUE TO SLOWLY SHIFT NE THROUGHOUT
THE NIGHT...REACHING FAR WESTERN KY BY 12Z TOMORROW. THIS MAY
ALLOW SOME MORE SHOWERS AND POSSIBLY EVEN AN ISOLATED
THUNDERSTORM TO DEVELOP AND MOVE INTO THE CWA LATER IN THE NIGHT
AND EARLY IN THE MORNING. BUT IN THE MEANTIME...IT LOOKS AS THINGS
ARE STARTING TO SETTLE DOWN ACROSS THE REGION.
CONTINUED CLOUD COVER...A HIGH AMOUNT OF MOISTURE...AND LIGHT
WINDS...WILL HELP TO MODERATE THE TEMPERATURES OVERNIGHT. CURRENT
READINGS OF UPPER 50S HAVE BEEN INCORPORATED INTO THE NEAR TERM
FORECAST...WITH ONLY A 3 TO 5 DEGREE DIURNAL FALL INTO THE LOW TO
MID 50S EXPECTED BY MORNING.
&&
.SHORT TERM...(THIS EVENING THROUGH THURSDAY NIGHT)
ISSUED AT 340 PM EDT WED APR 15 2015
18Z SFC ANALYSIS SHOWS THAT THE INVERTED TROUGH AXIS HAS SHIFTED
EAST TO ALONG THE SPINE OF THE APPALACHIANS WITH THE LOWER
MISSISSIPPI VALLEY LOW/S WARM FRONT LIFTING NORTH INTO KENTUCKY.
THE LIGHT PCPN AND OVERCAST CONDITIONS HAS KEPT MOST OF THE AREA
ON THE COOL SIDE TODAY...ESPECIALLY OUTSIDE OF THE CUMBERLAND
VALLEY. HOWEVER...THINNING CLOUDS AND A BREAK IN THE LIGHT RAIN
SHOULD ALLOW FOR SOME DECENT TEMP RISES OVER THE NEXT COUPLE OF
HOURS FOR ALL BUT THE FAR NORTHEAST. READINGS CURRENTLY VARY FROM
THE UPPER 50S IN THE NORTHEAST TO THE UPPER 60S IN THE SOUTH WHILE
DEWPOINTS RANGE FROM NEAR 60 SOUTH TO THE UPPER 40S IN THE FAR
NORTH. WINDS ARE GENERALLY FROM THE EAST TO NORTHEAST AT 10 TO 15
MPH OVER THE NORTHERN HALF OF THE AREA WHILE THEY ARE A BIT
LIGHTER AND MORE VARIABLE TO THE SOUTH. THE LIFTING WARM FRONT
MAY REINITIATE SHOWERS LATER IN THE AFTERNOON INTO THE EVENING...
PER THE LATEST HRRR AND NAM12...BUT RIGHT NOW THE RADAR SCOPE IS
PRETTY CLEAN. SHOULD CONVECTION REDEVELOP...SOME THUNDER MAY EVEN
BE POSSIBLE GIVEN THE RISING TEMPS/INSTABILITY...ESPECIALLY IN
THE SOUTH.
THE MODELS ARE IN GOOD AGREEMENT ALOFT THROUGH THE SHORT TERM
PORTION OF THE FORECAST AS A FEW CLUSTERS OF MID LEVEL ENERGY WILL
BRUSH KENTUCKY AS THEY MOVE INTO THE OHIO VALLEY TONIGHT ON THE
NORTHWEST FRINGE OF A BUILDING RIDGE. THE RIDGE FLATTENS A BIT ON
THURSDAY AS ADDITIONAL ENERGY PASSES THROUGH NORTHERN KENTUCKY
THAT AFTERNOON/OVERNIGHT AND INTO FRIDAY MORNING. TO THE WEST...A
SLOW MOVING CLOSED LOW SPINS ESSENTIALLY IN PLACE NEAR THE FOUR
CORNERS REGION OF THE COUNTRY...SERVING AS A SOURCE REGION FOR
ENERGY ABLE TO ESCAPE AND DRIFT EAST IN THE SOUTHERN STREAM THAT
CONTINUES TO DOMINATE KENTUCKY/S WX. GIVEN THE GENERAL MODEL
AGREEMENT HAVE FOLLOWED A BLEND WITH A LEAN TOWARD THE HRRR AND
NAM12 FOR WEATHER SPECIFICS DUE TO THEIR HIGHER RESOLUTION...
THOUGH CURRENT CONDITIONS AND TRENDS ARE ALSO OF HIGH RELEVANCE
INTO THE NEAR TERM PORTION OF THE FORECAST.
SENSIBLE WEATHER WILL FEATURE A POTENTIAL FOR SHOWERS INTO THE
EVENING AS THE SFC FRONT LIFTS NORTHEAST THROUGH THE AREA WITH A
THUNDERSTORM POSSIBLE...AS WELL. ADDITIONAL CONVECTION WILL BE
POSSIBLE INTO THURSDAY MORNING WITH THE SFC LOW TO THE SOUTHWEST
APPROACHING. THIS WILL LIKELY LIFT ANOTHER BOUNDARY THROUGH
EASTERN KENTUCKY DURING THE DAY WITH SHOWERS AND STRAY STORMS A
GOOD BET. THE PCPN CHANCES WILL DIMINISH INTO FRIDAY MORNING BUT
CANNOT GO DRY ATTM GIVEN THE ENVIRONMENT. THIS REMAINS A LOW
CONFIDENCE FORECAST WITH RESPECT TO SPECIFIC DETAILS BUT IN
GENERAL YOU CAB BANK ON RELATIVELY WARM AND MOIST CONDITIONS
CONTINUING.
USED THE SHORTBLEND GUIDANCE AS A STARTING POINT FOR T/TD/WIND
GRIDS THROUGH THE FIRST 18-24 HOURS OF THE FORECAST FOLLOWED BY
THE SUPERBLEND. GIVEN THE HUMID CONDITIONS MADE ONLY MINOR TERRAIN
BASED ADJUSTMENTS TO TEMPERATURES TONIGHT AND THURSDAY NIGHT. AS
FOR POPS...ENDED UP ON THE LOW SIDE OF MOS GUIDANCE TONIGHT AND
THURSDAY...BUT IN LINE FOR THURSDAY NIGHT.
.LONG TERM...(FRIDAY THROUGH WEDNESDAY)
ISSUED AT 340 PM EDT WED APR 15 2015
THE EXTENDED PERIOD WILL BE DOMINATED BY A LARGE CLOSED LOW OVER THE
FOUR CORNERS REGION WITH SOME SLIGHT RIDGING OVER THE EASTERN CONUS.
AFTER A SHORT WAVE IMPULSE...PROVIDING A ROUND OF RAINFALL TO THE
REGION...PUSHES THROUGH THE TN AND OH VALLEYS FRIDAY MORNING...
FRIDAY EVENING INTO SATURDAY MORNING WILL BE MOSTLY DRY. ON
SATURDAY...ANOTHER IMPULSE MOVING ALONG THE NORTHERN STREAM PUSHES
EWD TOWARDS THE GREAT LAKES REGION. AT THE SAME TIME...THE CLOSED
LOW EJECTS EWD AS WELL. THE ENERGY FROM THE CLOSED LOW THEN FEEDS
INTO THE NORTHERN STREAM TROUGH AND HELPS DEEPEN/INTENSIFY IT. THIS
SYSTEM WILL PROVIDE THE BEST CHANCE FOR A SIGNIFICANT AMOUNT OF
RAINFALL FOR EASTERN KENTUCKY IN THE SATURDAY NIGHT THROUGH MONDAY
MORNING TIME FRAME. THIS RAINFALL HAS THE POSSIBILITY OF BREAKING
THE JKL/S ALL-TIME APRIL RAINFALL RECORD...CURRENTLY WE HAVE HAD THE
SECOND WETTEST APRIL ON RECORD. IN FACT...THIS SYSTEM WILL SPREAD
PRECIP FROM THE NORTHERN MISSISSIPPI VALLEY REGION ACROSS MOST OF
THE EASTERN CONUS THROUGH TUESDAY. CLOSER TO HOME...TUESDAY AND
WEDNESDAY LOOKS TO BE FAIRLY QUIET...COOLER...AND DRY AS THE UPPER
LEVELS TRANSITION TO MORE OF A ZONAL FLOW PATTERN.
GFS AND ECMWF MODELS ACTUALLY HAVE GOOD AGREEMENT WITH THE EVOLUTION
OF THIS MAJOR SYSTEM. ADDITIONALLY...THERE LOOKS TO BE A STRONG
SURGE OF GULF MOISTURE WITH PW VALUES REACHING 1.50 INCHES IN SOME
LOCATIONS WITH SOME INSTABILITY PRESENT. THEREFORE...HAVE DECIDED TO
INCLUDED SLIGHT CHANCES OF THUNDER THROUGHOUT THE EXTENDED PERIOD
WITH LIKELY THUNDER DURING THE SUNDAY AFTERNOON THROUGH MONDAY
MORNING TIME FRAME. PROBABLY COULD HAVE UPPED POPS TO GO CATEGORICAL
ON SUNDAY/MONDAY MORNING BUT HAVE REMAINED CONSISTENT WITH NEIGHBORS
FOR NOW AND KEPT LIKELY POPS IN THE GRIDS. ALL IN ALL...BASED ON THE
CONTINUED WET PATTERN...THE MAIN CONCERN DURING THE EXTENDED PERIOD
WILL BE HEAVY RAINFALL WITH LOCALIZED FLOODING CONCERNS...ESPECIALLY
IN AREAS THAT RECEIVE SEVERAL ROUNDS OF RAINFALL AND WHERE RIVERS
AND CREEKS ARE STILL RUNNING HIGH.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z THURSDAY EVENING)
ISSUED AT 757 PM EDT WED APR 15 2015
A BIT OF AN UNSETTLED TAF OVER THE NEXT 24 HOURS. ISOLATED TO
SCATTERED SHOWERS CONTINUE ACROSS THE CWA THIS EVENING...BUT ARE
SHOWING A DISSIPATING TREND AS LOW LEVEL FLOW SLOWLY SHIFTS TO A
MORE SOUTHEASTERLY DIRECTION FOR TONIGHT. THIS DRIER DOWNSLOPING
FLOW WILL DO ONE OF TWO THINGS. IT WILL EITHER HELP TO SCOUR OUT
THE LOWER CIGS...OR IT COULD LEAD TO A STRONG INVERSION WHICH
TRAPS SOME OF THE MOISTURE IN THE FORM OF A LOW STRATUS DECK AT
SOME OF THE TAF SITES. AS SUCH... CONFIDENCE IS LOW AS TO WHICH
WILL OCCUR...WITH SOME SITES LIKELY FLUCTUATING BETWEEN MVFR AND
IFR CIGS. EITHER WAY...EXPECT CIGS TO IMPROVE WITH DAYTIME HEATING
TOMORROW MORNING. HOWEVER...VCSH WILL LIKELY STILL POSE A THREAT
THROUGHOUT THE DAY...WITH CIGS FLUCTUATING ONCE MORE BETWEEN MVFR
AND VFR. VIS SHOULD REMAIN VFR...THOUGH SOME OF THE HEAVIER
SHOWERS COULD CAUSE SOME TEMPORARY RESTRICTIONS. WINDS ARE
EXPECTED TO REMAIN LIGHT AND VARIABLE.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...JMW
SHORT TERM...GREIF
LONG TERM...JVM
AVIATION...JMW
AREA FORECAST DISCUSSION
NWS JACKSON KY
800 PM EDT WED APR 15 2015
.SHORT TERM...(THIS EVENING THROUGH THURSDAY NIGHT)
ISSUED AT 340 PM EDT WED APR 15 2015
18Z SFC ANALYSIS SHOWS THAT THE INVERTED TROUGH AXIS HAS SHIFTED
EAST TO ALONG THE SPINE OF THE APPALACHIANS WITH THE LOWER
MISSISSIPPI VALLEY LOW/S WARM FRONT LIFTING NORTH INTO KENTUCKY.
THE LIGHT PCPN AND OVERCAST CONDITIONS HAS KEPT MOST OF THE AREA
ON THE COOL SIDE TODAY...ESPECIALLY OUTSIDE OF THE CUMBERLAND
VALLEY. HOWEVER...THINNING CLOUDS AND A BREAK IN THE LIGHT RAIN
SHOULD ALLOW FOR SOME DECENT TEMP RISES OVER THE NEXT COUPLE OF
HOURS FOR ALL BUT THE FAR NORTHEAST. READINGS CURRENTLY VARY FROM
THE UPPER 50S IN THE NORTHEAST TO THE UPPER 60S IN THE SOUTH WHILE
DEWPOINTS RANGE FROM NEAR 60 SOUTH TO THE UPPER 40S IN THE FAR
NORTH. WINDS ARE GENERALLY FROM THE EAST TO NORTHEAST AT 10 TO 15
MPH OVER THE NORTHERN HALF OF THE AREA WHILE THEY ARE A BIT
LIGHTER AND MORE VARIABLE TO THE SOUTH. THE LIFTING WARM FRONT
MAY REINITIATE SHOWERS LATER IN THE AFTERNOON INTO THE EVENING...
PER THE LATEST HRRR AND NAM12...BUT RIGHT NOW THE RADAR SCOPE IS
PRETTY CLEAN. SHOULD CONVECTION REDEVELOP...SOME THUNDER MAY EVEN
BE POSSIBLE GIVEN THE RISING TEMPS/INSTABILITY...ESPECIALLY IN
THE SOUTH.
THE MODELS ARE IN GOOD AGREEMENT ALOFT THROUGH THE SHORT TERM
PORTION OF THE FORECAST AS A FEW CLUSTERS OF MID LEVEL ENERGY WILL
BRUSH KENTUCKY AS THEY MOVE INTO THE OHIO VALLEY TONIGHT ON THE
NORTHWEST FRINGE OF A BUILDING RIDGE. THE RIDGE FLATTENS A BIT ON
THURSDAY AS ADDITIONAL ENERGY PASSES THROUGH NORTHERN KENTUCKY
THAT AFTERNOON/OVERNIGHT AND INTO FRIDAY MORNING. TO THE WEST...A
SLOW MOVING CLOSED LOW SPINS ESSENTIALLY IN PLACE NEAR THE FOUR
CORNERS REGION OF THE COUNTRY...SERVING AS A SOURCE REGION FOR
ENERGY ABLE TO ESCAPE AND DRIFT EAST IN THE SOUTHERN STREAM THAT
CONTINUES TO DOMINATE KENTUCKY/S WX. GIVEN THE GENERAL MODEL
AGREEMENT HAVE FOLLOWED A BLEND WITH A LEAN TOWARD THE HRRR AND
NAM12 FOR WEATHER SPECIFICS DUE TO THEIR HIGHER RESOLUTION...
THOUGH CURRENT CONDITIONS AND TRENDS ARE ALSO OF HIGH RELEVANCE
INTO THE NEAR TERM PORTION OF THE FORECAST.
SENSIBLE WEATHER WILL FEATURE A POTENTIAL FOR SHOWERS INTO THE
EVENING AS THE SFC FRONT LIFTS NORTHEAST THROUGH THE AREA WITH A
THUNDERSTORM POSSIBLE...AS WELL. ADDITIONAL CONVECTION WILL BE
POSSIBLE INTO THURSDAY MORNING WITH THE SFC LOW TO THE SOUTHWEST
APPROACHING. THIS WILL LIKELY LIFT ANOTHER BOUNDARY THROUGH
EASTERN KENTUCKY DURING THE DAY WITH SHOWERS AND STRAY STORMS A
GOOD BET. THE PCPN CHANCES WILL DIMINISH INTO FRIDAY MORNING BUT
CANNOT GO DRY ATTM GIVEN THE ENVIRONMENT. THIS REMAINS A LOW
CONFIDENCE FORECAST WITH RESPECT TO SPECIFIC DETAILS BUT IN
GENERAL YOU CAB BANK ON RELATIVELY WARM AND MOIST CONDITIONS
CONTINUING.
USED THE SHORTBLEND GUIDANCE AS A STARTING POINT FOR T/TD/WIND
GRIDS THROUGH THE FIRST 18-24 HOURS OF THE FORECAST FOLLOWED BY
THE SUPERBLEND. GIVEN THE HUMID CONDITIONS MADE ONLY MINOR TERRAIN
BASED ADJUSTMENTS TO TEMPERATURES TONIGHT AND THURSDAY NIGHT. AS
FOR POPS...ENDED UP ON THE LOW SIDE OF MOS GUIDANCE TONIGHT AND
THURSDAY...BUT IN LINE FOR THURSDAY NIGHT.
.LONG TERM...(FRIDAY THROUGH WEDNESDAY)
ISSUED AT 340 PM EDT WED APR 15 2015
THE EXTENDED PERIOD WILL BE DOMINATED BY A LARGE CLOSED LOW OVER THE
FOUR CORNERS REGION WITH SOME SLIGHT RIDGING OVER THE EASTERN CONUS.
AFTER A SHORT WAVE IMPULSE...PROVIDING A ROUND OF RAINFALL TO THE
REGION...PUSHES THROUGH THE TN AND OH VALLEYS FRIDAY MORNING...
FRIDAY EVENING INTO SATURDAY MORNING WILL BE MOSTLY DRY. ON
SATURDAY...ANOTHER IMPULSE MOVING ALONG THE NORTHERN STREAM PUSHES
EWD TOWARDS THE GREAT LAKES REGION. AT THE SAME TIME...THE CLOSED
LOW EJECTS EWD AS WELL. THE ENERGY FROM THE CLOSED LOW THEN FEEDS
INTO THE NORTHERN STREAM TROUGH AND HELPS DEEPEN/INTENSIFY IT. THIS
SYSTEM WILL PROVIDE THE BEST CHANCE FOR A SIGNIFICANT AMOUNT OF
RAINFALL FOR EASTERN KENTUCKY IN THE SATURDAY NIGHT THROUGH MONDAY
MORNING TIME FRAME. THIS RAINFALL HAS THE POSSIBILITY OF BREAKING
THE JKL/S ALL-TIME APRIL RAINFALL RECORD...CURRENTLY WE HAVE HAD THE
SECOND WETTEST APRIL ON RECORD. IN FACT...THIS SYSTEM WILL SPREAD
PRECIP FROM THE NORTHERN MISSISSIPPI VALLEY REGION ACROSS MOST OF
THE EASTERN CONUS THROUGH TUESDAY. CLOSER TO HOME...TUESDAY AND
WEDNESDAY LOOKS TO BE FAIRLY QUIET...COOLER...AND DRY AS THE UPPER
LEVELS TRANSITION TO MORE OF A ZONAL FLOW PATTERN.
GFS AND ECMWF MODELS ACTUALLY HAVE GOOD AGREEMENT WITH THE EVOLUTION
OF THIS MAJOR SYSTEM. ADDITIONALLY...THERE LOOKS TO BE A STRONG
SURGE OF GULF MOISTURE WITH PW VALUES REACHING 1.50 INCHES IN SOME
LOCATIONS WITH SOME INSTABILITY PRESENT. THEREFORE...HAVE DECIDED TO
INCLUDED SLIGHT CHANCES OF THUNDER THROUGHOUT THE EXTENDED PERIOD
WITH LIKELY THUNDER DURING THE SUNDAY AFTERNOON THROUGH MONDAY
MORNING TIME FRAME. PROBABLY COULD HAVE UPPED POPS TO GO CATEGORICAL
ON SUNDAY/MONDAY MORNING BUT HAVE REMAINED CONSISTENT WITH NEIGHBORS
FOR NOW AND KEPT LIKELY POPS IN THE GRIDS. ALL IN ALL...BASED ON THE
CONTINUED WET PATTERN...THE MAIN CONCERN DURING THE EXTENDED PERIOD
WILL BE HEAVY RAINFALL WITH LOCALIZED FLOODING CONCERNS...ESPECIALLY
IN AREAS THAT RECEIVE SEVERAL ROUNDS OF RAINFALL AND WHERE RIVERS
AND CREEKS ARE STILL RUNNING HIGH.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z THURSDAY EVENING)
ISSUED AT 757 PM EDT WED APR 15 2015
A BIT OF AN UNSETTLED TAF OVER THE NEXT 24 HOURS. ISOLATED TO
SCATTERED SHOWERS CONTINUE ACROSS THE CWA THIS EVENING...BUT ARE
SHOWING A DISSIPATING TREND AS LOW LEVEL FLOW SLOWLY SHIFTS TO A
MORE SOUTHEASTERLY DIRECTION FOR TONIGHT. THIS DRIER DOWNSLOPING
FLOW WILL DO ONE OF TWO THINGS. IT WILL EITHER HELP TO SCOUR OUT
THE LOWER CIGS...OR IT COULD LEAD TO A STRONG INVERSION WHICH
TRAPS SOME OF THE MOISTURE IN THE FORM OF A LOW STRATUS DECK AT
SOME OF THE TAF SITES. AS SUCH... CONFIDENCE IS LOW AS TO WHICH
WILL OCCUR...WITH SOME SITES LIKELY FLUCTUATING BETWEEN MVFR AND
IFR CIGS. EITHER WAY...EXPECT CIGS TO IMPROVE WITH DAYTIME HEATING
TOMORROW MORNING. HOWEVER...VCSH WILL LIKELY STILL POSE A THREAT
THROUGHOUT THE DAY...WITH CIGS FLUCTUATING ONCE MORE BETWEEN MVFR
AND VFR. VIS SHOULD REMAIN VFR...THOUGH SOME OF THE HEAVIER
SHOWERS COULD CAUSE SOME TEMPORARY RESTRICTIONS. WINDS ARE
EXPECTED TO REMAIN LIGHT AND VARIABLE.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...GREIF
LONG TERM...JVM
AVIATION...JMW
AREA FORECAST DISCUSSION
NWS JACKSON KY
345 PM EDT TUE APR 14 2015
.UPDATE...
ISSUED AT 345 PM EDT TUE APR 14 2015
GIVEN THAT MUCH OF THE RAIN HAS SUBSIDED ACROSS THE REGION WE HAVE
DROPPED THE FLOOD WATCH FOR THE REGION. ONGOING FLOODING WILL BE
COVERED BY FLOOD WARNINGS AND ADVISORIES.
&&
.SHORT TERM...(THIS EVENING THROUGH WEDNESDAY NIGHT)
ISSUED AT 315 PM EDT TUE APR 14 2015
SURFACE ANALYSIS SHOWS A BROADER AREA OF SURFACE LOW PRESSURE
CENTERED JUST TO THE SOUTH ACROSS EASTERN TENNESSEE THIS
AFTERNOON. THIS ALONG WITH A FRONTAL BOUNDARY HAS BEEN THE FOCAL
POINT OF LIFT FOR THE RAINFALL THAT HAS OCCURRED TODAY. LATEST
WSR- 88D RADAR AT 3 PM DOES INDICATE THAT MUCH OF OF THE HEAVIER
RAINFALL HAS WANED THIS AFTERNOON. THIS AREA OF LOW PRESSURE IS
EXPECTED TO PROGRESS EAST INTO THE CAROLINAS AS WE MOVE TONIGHT
ALONG WITH THE RAINFALL.
THE QUESTION THAT REMAINS FOR OVERNIGHT HOURS IS WHAT WILL HAPPEN
WITH YET ANOTHER UPPER LEVEL WAVE TRACKING NORTHEAST OUT OF THE
LOWER MISSISSIPPI RIVER VALLEY. SOME OF THE MESOSCALE MODELS SUCH
AS THE HRRR AND RAP WOULD SUGGEST WE WILL GET AT LEAST CLIPPED BY
THIS AREA OF RAIN ASSOCIATED WITH THE WAVE. RIGHT NOW WE ARE
CARRYING SLIGHT TO CHANCE POPS WITH HIGHER POPS ACROSS SOUTHEAST
KENTUCKY. THESE POPS COULD NEED TO BE HIGHER LATE EVENING INTO THE
OVERNIGHT DEPENDING ON THE PROPAGATION OF THIS WAVE OF ENERGY.
UNDER THIS GENERAL SOUTHWEST FLOW ALOFT WILL BRING YET ANOTHER
UPPER LEVEL SHORTWAVE AS WE MOVE INTO LATER WEDNESDAY INTO
WEDNESDAY NIGHT. THIS WILL BRING ANOTHER ROUND INCREASED ROUND OF
SHOWERS FROM SOUTHWEST TO NORTHEAST OVERNIGHT WEDNESDAY AS THIS
WAVE TRACKS NORTHEAST AND DIFFLUENCE ALOFT IN PLACE.
.LONG TERM...(THURSDAY THROUGH TUESDAY)
ISSUED AT 335 PM EDT TUE APR 14 2015
THE UPPER LEVEL PATTERN SHOWS NORTHERN STREAM FLOW SITUATED ALONG
THE CANADIAN/US BORDER THROUGH THE EXTENDED PERIOD...WHILE THE
EASTERN US IS DOMINATED BY RIDGING AND THE WESTERN US IS DOMINATED
BY A SPLIT FLOW WITH A CUT OFF LOW IN THE SOUTHERN STREAM. A SERIES
OF DISTURBANCES WILL EJECT OUT OF THE SOUTHERN STREAM AND PASS
THROUGH THE TN AND OH VALLEYS DURING THE LATTER HALF OF THE WORK
WEEK...BRINGING PRECIPITATION...POSSIBLY HEAVY AT TIMES.
SUNDAY...THE CUT OFF LOW IS PROGGED TO LIFT OUT OF THE SRN STREAM
AND MERGE WITH A NORTHERN STREAM UL TROUGH WHICH ENDS UP TURNING
INTO A LARGE ROBUST SYSTEM. THIS SYSTEM IS PROGGED TO SPREAD
PRECIPITATION OVER THE NORTHERN PLAINS/UPPER MISSISSIPPI VALLEY
SOUTHWARD ACROSS OUR REGION AND INTO THE SOUTHEASTERN US FROM
SUNDAY AFTERNOON THROUGH LATE MONDAY NIGHT. THE UL PATTERN IS
THEN DOMINATED BY THE UL TROUGH WHICH SLOWLY MOVES ALONG THE
US/CANADIAN BORDER...NORTH OF THE GREAT LAKES...THROUGH THE END
OF THE EXTENDED PERIOD. THIS WILL ALLOW FOR TEMPERATURES TO DROP
BACK DOWN TO SEASONABLE LEVELS NEXT TUES/WED AND POSSIBLY BRING A
SHORT BREAK TO THE WET WEATHER.
AT THE SFC...THE UL DISTURBANCES WILL BRING CONTINUED CHANCES FOR
RAIN THURSDAY THROUGH LATE MONDAY. THERE MAY BE MOMENTARY BREAKS
IN THE RAIN ON SATURDAY BUT OVERALL THIS WILL BE ANOTHER WET
PERIOD WITH ABOVE AVERAGE RAINFALL. SOUTHERLY FLOW WILL ALSO
PERSIST...USHERING IN WARM MOIST AIR...WHICH ENHANCES THE RAIN
POTENTIAL THROUGH THE PERIOD. MODEL SOUNDINGS SHOW PW VALUES
FLUCTUATE BETWEEN 1.0" AND 1.4" DURING THIS PERIOD...WHICH IS WELL
ABOVE THE 2 STANDARD DEVIATIONS ABOVE NORMAL. BY LATE MONDAY/EARLY
TUESDAY...THE UL TROUGH SHOULD FINALLY PUSH EAST...PROVIDING
ANOTHER BREAK IN RAINFALL BY TUESDAY AFTERNOON.
THERE ARE SUBSTANTIAL DIFFERENCES BETWEEN THE GFS AND
ECMWF...ESPECIALLY DURING THE WEEKEND PERIOD AND BEYOND. SO HAVE
STUCK CLOSE TO THE CR SUPERBLEND FOR THE MAJORITY OF THE EXTENDED
PERIOD. ALSO KEPT SLIGHT CHANCE FOR THUNDER THROUGHOUT THE PERIOD.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON)
ISSUED AT 146 PM EDT TUE APR 14 2015
STILL SOME AREAS OF LIGHT TO MODERATE RAIN MOVING ACROSS PORTIONS
OF EASTERN KENTUCKY THIS AFTERNOON. THE COVERAGE HAS DROPPED OFF
AS WE HAVE MOVE THROUGH THE DAY. UPSTREAM OBS WOULD SUGGEST A
REPRIEVE IN THE IFR CEILINGS THIS AFTERNOON...HOWEVER IT DOES
LOOK LIKE WE WILL SEE A DECREASE BACK TO IFR AS WE MOVE INTO THE
EVENING AND OVERNIGHT. THERE WILL BE A BIT OF A GRADIENT AS THE
LOW PRESSURE PASSES TO NEAR THE TN BORDER. THIS WILL ALLOW FOR
SOME GUSTY WINDS WHICH ARE ALREADY BEING SEEN AT SYM THIS HOUR.
THESE WIND WILL SUBSIDE AS WE MOVE INTO THE EVENING.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...DJ
SHORT TERM...DJ
LONG TERM...JVM
AVIATION...DJ
AREA FORECAST DISCUSSION
NWS JACKSON KY
336 PM EDT TUE APR 14 2015
.SHORT TERM...(THIS EVENING THROUGH WEDNESDAY NIGHT)
ISSUED AT 315 PM EDT TUE APR 14 2015
SURFACE ANALYSIS SHOWS A BROADER AREA OF SURFACE LOW PRESSURE
CENTERED JUST TO THE SOUTH ACROSS EASTERN TENNESSEE THIS
AFTERNOON. THIS ALONG WITH A FRONTAL BOUNDARY HAS BEEN THE FOCAL
POINT OF LIFT FOR THE RAINFALL THAT HAS OCCURRED TODAY. LATEST
WSR- 88D RADAR AT 3 PM DOES INDICATE THAT MUCH OF OF THE HEAVIER
RAINFALL HAS WANED THIS AFTERNOON. THIS AREA OF LOW PRESSURE IS
EXPECTED TO PROGRESS EAST INTO THE CAROLINAS AS WE MOVE TONIGHT
ALONG WITH THE RAINFALL.
THE QUESTION THAT REMAINS FOR OVERNIGHT HOURS IS WHAT WILL HAPPEN
WITH YET ANOTHER UPPER LEVEL WAVE TRACKING NORTHEAST OUT OF THE
LOWER MISSISSIPPI RIVER VALLEY. SOME OF THE MESOSCALE MODELS SUCH
AS THE HRRR AND RAP WOULD SUGGEST WE WILL GET AT LEAST CLIPPED BY
THIS AREA OF RAIN ASSOCIATED WITH THE WAVE. RIGHT NOW WE ARE
CARRYING SLIGHT TO CHANCE POPS WITH HIGHER POPS ACROSS SOUTHEAST
KENTUCKY. THESE POPS COULD NEED TO BE HIGHER LATE EVENING INTO THE
OVERNIGHT DEPENDING ON THE PROPAGATION OF THIS WAVE OF ENERGY.
UNDER THIS GENERAL SOUTHWEST FLOW ALOFT WILL BRING YET ANOTHER
UPPER LEVEL SHORTWAVE AS WE MOVE INTO LATER WEDNESDAY INTO
WEDNESDAY NIGHT. THIS WILL BRING ANOTHER ROUND INCREASED ROUND OF
SHOWERS FROM SOUTHWEST TO NORTHEAST OVERNIGHT WEDNESDAY AS THIS
WAVE TRACKS NORTHEAST AND DIFFLUENCE ALOFT IN PLACE.
.LONG TERM...(THURSDAY THROUGH TUESDAY)
ISSUED AT 335 PM EDT TUE APR 14 2015
THE UPPER LEVEL PATTERN SHOWS NORTHERN STREAM FLOW SITUATED ALONG
THE CANADIAN/US BORDER THROUGH THE EXTENDED PERIOD...WHILE THE
EASTERN US IS DOMINATED BY RIDGING AND THE WESTERN US IS DOMINATED
BY A SPLIT FLOW WITH A CUT OFF LOW IN THE SOUTHERN STREAM. A SERIES
OF DISTURBANCES WILL EJECT OUT OF THE SOUTHERN STREAM AND PASS
THROUGH THE TN AND OH VALLEYS DURING THE LATTER HALF OF THE WORK
WEEK...BRINGING PRECIPITATION...POSSIBLY HEAVY AT TIMES.
SUNDAY...THE CUT OFF LOW IS PROGGED TO LIFT OUT OF THE SRN STREAM
AND MERGE WITH A NORTHERN STREAM UL TROUGH WHICH ENDS UP TURNING
INTO A LARGE ROBUST SYSTEM. THIS SYSTEM IS PROGGED TO SPREAD
PRECIPITATION OVER THE NORTHERN PLAINS/UPPER MISSISSIPPI VALLEY
SOUTHWARD ACROSS OUR REGION AND INTO THE SOUTHEASTERN US FROM
SUNDAY AFTERNOON THROUGH LATE MONDAY NIGHT. THE UL PATTERN IS
THEN DOMINATED BY THE UL TROUGH WHICH SLOWLY MOVES ALONG THE
US/CANADIAN BORDER...NORTH OF THE GREAT LAKES...THROUGH THE END
OF THE EXTENDED PERIOD. THIS WILL ALLOW FOR TEMPERATURES TO DROP
BACK DOWN TO SEASONABLE LEVELS NEXT TUES/WED AND POSSIBLY BRING A
SHORT BREAK TO THE WET WEATHER.
AT THE SFC...THE UL DISTURBANCES WILL BRING CONTINUED CHANCES FOR
RAIN THURSDAY THROUGH LATE MONDAY. THERE MAY BE MOMENTARY BREAKS
IN THE RAIN ON SATURDAY BUT OVERALL THIS WILL BE ANOTHER WET
PERIOD WITH ABOVE AVERAGE RAINFALL. SOUTHERLY FLOW WILL ALSO
PERSIST...USHERING IN WARM MOIST AIR...WHICH ENHANCES THE RAIN
POTENTIAL THROUGH THE PERIOD. MODEL SOUNDINGS SHOW PW VALUES
FLUCTUATE BETWEEN 1.0" AND 1.4" DURING THIS PERIOD...WHICH IS WELL
ABOVE THE 2 STANDARD DEVIATIONS ABOVE NORMAL. BY LATE MONDAY/EARLY
TUESDAY...THE UL TROUGH SHOULD FINALLY PUSH EAST...PROVIDING
ANOTHER BREAK IN RAINFALL BY TUESDAY AFTERNOON.
THERE ARE SUBSTANTIAL DIFFERENCES BETWEEN THE GFS AND
ECMWF...ESPECIALLY DURING THE WEEKEND PERIOD AND BEYOND. SO HAVE
STUCK CLOSE TO THE CR SUPERBLEND FOR THE MAJORITY OF THE EXTENDED
PERIOD. ALSO KEPT SLIGHT CHANCE FOR THUNDER THROUGHOUT THE PERIOD.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON)
ISSUED AT 146 PM EDT TUE APR 14 2015
STILL SOME AREAS OF LIGHT TO MODERATE RAIN MOVING ACROSS PORTIONS
OF EASTERN KENTUCKY THIS AFTERNOON. THE COVERAGE HAS DROPPED OFF
AS WE HAVE MOVE THROUGH THE DAY. UPSTREAM OBS WOULD SUGGEST A
REPRIEVE IN THE IFR CEILINGS THIS AFTERNOON...HOWEVER IT DOES
LOOK LIKE WE WILL SEE A DECREASE BACK TO IFR AS WE MOVE INTO THE
EVENING AND OVERNIGHT. THERE WILL BE A BIT OF A GRADIENT AS THE
LOW PRESSURE PASSES TO NEAR THE TN BORDER. THIS WILL ALLOW FOR
SOME GUSTY WINDS WHICH ARE ALREADY BEING SEEN AT SYM THIS HOUR.
THESE WIND WILL SUBSIDE AS WE MOVE INTO THE EVENING.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
FLOOD WATCH UNTIL 5 PM EDT THIS AFTERNOON FOR KYZ080-084>088-104-
106>120.
&&
$$
SHORT TERM...DJ
LONG TERM...JVM
AVIATION...DJ
AREA FORECAST DISCUSSION
NWS LOUISVILLE KY
1250 PM EDT Tue Apr 14 2015
...Updated Aviation Discussion...
...Forecast Update...
Issued at 1035 AM EDT Tue Apr 14 2015
Band continues over southern Indiana, but also still have some light
to moderate rains over Kentucky. Pattern resembles a setup that
would generate a lot of snow in the winter, but fortunately we are
20-30 degrees warmer! Despite the lifting of the shortwave, into
Indiana now, we still have quite a bit of low-level lift to deal
with for a few more hours, so have raised pops some more into the
afternoon hours.
As for the Flood Watch, will let that expire at 15Z as planned.
Already have upgraded to areal flood warnings in most of the watch
locations, so no more need for a double product. Will update the
zones at 15Z to remove that headline.
Issued at 930 AM EDT Tue Apr 14 2015
Heaviest band of precip has lifted north into southern Indiana, but
continue with moderate rains over our east and southeast counties.
Areal flood warnings are out with several reports of water over
roads coming in for those areas. We should not have such a problem
over the north, but will keep watch over the next hour or two until
the shortwave noted on water vapor imagery kicks out of here and the
forcing for these rains dies down.
Issued at 650 AM EDT Tue Apr 14 2015
Just a quick update on latest trends. Widespread rain continues at
this time over most of central KY as the mid-level shortwave heads
northeast across western TN at this time. Pockets of moderate to
heavy rain are occurring throughout the region. This could cause
significant ponding of water on some roads and low-lying areas, and
some creeks could possibly overflow. However, have received no
reports of flooding at this time.
06z models and latest HRRR reflecting radar trends well. The sharp
northern edge of the rain along and south of the OH River has
relaxed some and spread a bit farther north as expected. A few
heavier rain elements are now showing up near Evansville and just
northeast of Louisville. The heaviest steadiest rains will remain
within the Flood Watch area, but showers will spread northeast
across much of south-central IN over the next hour or two.
Otherwise, forecast is on track with just some tweaks to hourly POPs
to match latest trends.
.SHORT TERM (Now through Wednesday)...
Issued at 315 AM EDT Tue Apr 14 2015
...Flood Watch continues this morning for parts of central KY...
A solid area of rain has evolved in a WSW-ENE axis across central
KY early this morning, ahead of a pronounced shortwave in water
vapor imagery moving from AR/MS into western TN and an associated
surface low pressure system. Within this rain are numerous areas of
moderate rain. At this time, there is a distinct northern boundary
to the rain along and just south of the OH River associated with a
deformation zone. The latest few HRRR runs have shown that rain just
ahead of the shortwave may move a little farther north and be slower
to depart than previous forecasts, which the 00z NAM also hinted at.
These models are slower and farther north than the 00z GFS, which
seems reasonable. Thus, despite the current tight northern precip
edge, more showers should move back across the Louisville metro and
into at least parts of south-central IN later this morning,
continuing during much of the morning. However, the heaviest rain
should continue to fall out in an axis to the east of the shortwave.
The current Flood Watch looks good, although decent rains will fall
a county or so north of the Watch as well, but will keep the area
unchanged at this time. The overall trend should be for more bands
of showers to form east of the shortwave then rotate north and east.
This should keep highest rainfall totals in an axis from about BWG
to LEX and a row of counties or so south. Still looks like 1 to 2
inches of rain is a good bet in this axis, with locally 2+ inches
possible in a few spots. However, since rainfall is not truly
convective and since rain rates should not increase much more than
at present, widespread flash flooding is not likely. Instead,
significant ponding and some areal flooding of roads, low-lying
areas, creeks, and small streams may occur. Slightly lower rain
totals are expected over our extreme southeast south-central KY
counties. While showers will continue past the 15 UTC expiration
time of the Watch, will not change it at this time. This can be
locally extended if need be later this morning pending latest trends
and reports.
Rainfall will diminish this afternoon for most areas, but scattered
showers should continue over our east and southeast counties
overcast skies persist. Over south-central IN, some breaks in the
clouds could occur later this afternoon.
High temperatures today are tricky. Values at this time may not go
up much if any today. Matter of fact, could see readings fall a bit
as a brisk northeast wind develops along with the low clouds and
showers in parts of central KY. Will keep readings in the upper 50s
over much of east-central KY west-southwestward, with lower-mid 60s
for south-central KY, again with highest values this morning. Also,
expect lower-mid 60s in south-central IN where low clouds will scour
out and showers will end this afternoon. Lows tonight should range
from the mid 40s to lower 50s with a cloudy sky south and east, and
partly to mostly cloudy north and west.
On Wednesday, mid-level flow will begin to back again, resulting in
clouds moving back northward. There could be some scattered showers
especially across south-central KY, although there are no clear
forcing mechanics at this time. Expect highs in the mid 60s to lower
70s.
.LONG TERM (Wednesday Night through Monday)...
Issued at 325 AM EDT Tue Apr 14 2015
...Above Normal Rainfall Expected This Week...
In general terms, there is not a whole lot of change in the guidance
for the extended forecast period. The synoptic flow aloft will be
characterized by a fast northern jet flow confined to the
US/Canadian border region, while a split flow pattern will be in
place across the western US with a cut off low in the southern
stream. Multiple wave packets will eject out of the southern stream
and pass through the region in the mid-late part of the week,
bringing precipitation with the potential for heavy rainfall. By
late in the period, the cut off low over the SW US is expected to
lift out and merge with a northern stream wave which looks to turn
into a rather large gyre over the northern Great Lakes by early next
week. This would bring drier and cooler than normal conditions to
the region.
It does appear that we`ll see the first wave push through the region
on Thursday with a secondary wave coming in Friday night and early
Saturday. Combination of lift with the associated waves and plenty
of Gulf moisture will lead to widespread rainfall, some heavy, which
could result in renewed hydrologic concerns through the period.
This would be especially true across our southern half of the
forecast area...mainly south of the Parkways. The weekend does not
look to be an entire wash out, but Saturday morning will probably
remain a bit unsettled as the aforementioned wave ejects through the
region. There is a growing consensus in the data that upper level
ridging will build in during the afternoon to allow the region to
dry out a bit. Thus, will continue to run chance PoPs in the
forecast for the early part of Saturday and then allow PoPs to
decrease throughout the remainder of the day and into Sunday.
As the upper low out over the southwest US lifts out and combines
with the northern stream wave pushing through, we should see a
return of wet weather as we head into late Sunday and Monday. More
showers with some thunderstorms looks likely.
As for temperatures, have generally stuck close to the SuperBlend
consensus guidance for temperatures. This will result in daytime
highs generally in the upper 60s to the lower 70s for highs and
overnight lows in the 50s. These temperature forecasts will likely
see some sort of modulation in subsequent forecasts as the timing
issues in the upper level waves moving through the area become more
clearly defined in the coming days.
&&
.AVIATION (18Z TAF Update)...
Updated at 1245 PM EDT Tue Apr 14 2015
Conditions slowly improving at area sites, as upper forcing for this
morning`s rains lifts quickly northeast. Enough moisture fell though
over south central KY to keep the forecast pessimistic for KBWG.
KSDF/KLEX are looking better in current obs, so just have a few more
hours of light rain. High pressure will move across the Great Lakes
this afternoon and tonight, keeping a general northeasterly winds
this period.
&&
.LMK WATCHES/WARNINGS/ADVISORIES...
KY...NONE.
IN...NONE.
&&
$$
Updates........RJS/TWF
Short Term.....TWF
Long Term......MJ
Aviation.......RJS
AREA FORECAST DISCUSSION
NWS LOUISVILLE KY
1037 AM EDT Tue Apr 14 2015
...Forecast Update...
Issued at 1035 AM EDT Tue Apr 14 2015
Band continues over southern Indiana, but also still have some light
to moderate rains over Kentucky. Pattern resembles a setup that
would generate a lot of snow in the winter, but fortunately we are
20-30 degrees warmer! Despite the lifting of the shortwave, into
Indiana now, we still have quite a bit of low-level lift to deal
with for a few more hours, so have raised pops some more into the
afternoon hours.
As for the Flood Watch, will let that expire at 15Z as planned.
Already have upgraded to areal flood warnings in most of the watch
locations, so no more need for a double product. Will update the
zones at 15Z to remove that headline.
Issued at 930 AM EDT Tue Apr 14 2015
Heaviest band of precip has lifted north into southern Indiana, but
continue with moderate rains over our east and southeast counties.
Areal flood warnings are out with several reports of water over
roads coming in for those areas. We should not have such a problem
over the north, but will keep watch over the next hour or two until
the shortwave noted on water vapor imagery kicks out of here and the
forcing for these rains dies down.
Issued at 650 AM EDT Tue Apr 14 2015
Just a quick update on latest trends. Widespread rain continues at
this time over most of central KY as the mid-level shortwave heads
northeast across western TN at this time. Pockets of moderate to
heavy rain are occurring throughout the region. This could cause
significant ponding of water on some roads and low-lying areas, and
some creeks could possibly overflow. However, have received no
reports of flooding at this time.
06z models and latest HRRR reflecting radar trends well. The sharp
northern edge of the rain along and south of the OH River has
relaxed some and spread a bit farther north as expected. A few
heavier rain elements are now showing up near Evansville and just
northeast of Louisville. The heaviest steadiest rains will remain
within the Flood Watch area, but showers will spread northeast
across much of south-central IN over the next hour or two.
Otherwise, forecast is on track with just some tweaks to hourly POPs
to match latest trends.
.SHORT TERM (Now through Wednesday)...
Issued at 315 AM EDT Tue Apr 14 2015
...Flood Watch continues this morning for parts of central KY...
A solid area of rain has evolved in a WSW-ENE axis across central
KY early this morning, ahead of a pronounced shortwave in water
vapor imagery moving from AR/MS into western TN and an associated
surface low pressure system. Within this rain are numerous areas of
moderate rain. At this time, there is a distinct northern boundary
to the rain along and just south of the OH River associated with a
deformation zone. The latest few HRRR runs have shown that rain just
ahead of the shortwave may move a little farther north and be slower
to depart than previous forecasts, which the 00z NAM also hinted at.
These models are slower and farther north than the 00z GFS, which
seems reasonable. Thus, despite the current tight northern precip
edge, more showers should move back across the Louisville metro and
into at least parts of south-central IN later this morning,
continuing during much of the morning. However, the heaviest rain
should continue to fall out in an axis to the east of the shortwave.
The current Flood Watch looks good, although decent rains will fall
a county or so north of the Watch as well, but will keep the area
unchanged at this time. The overall trend should be for more bands
of showers to form east of the shortwave then rotate north and east.
This should keep highest rainfall totals in an axis from about BWG
to LEX and a row of counties or so south. Still looks like 1 to 2
inches of rain is a good bet in this axis, with locally 2+ inches
possible in a few spots. However, since rainfall is not truly
convective and since rain rates should not increase much more than
at present, widespread flash flooding is not likely. Instead,
significant ponding and some areal flooding of roads, low-lying
areas, creeks, and small streams may occur. Slightly lower rain
totals are expected over our extreme southeast south-central KY
counties. While showers will continue past the 15 UTC expiration
time of the Watch, will not change it at this time. This can be
locally extended if need be later this morning pending latest trends
and reports.
Rainfall will diminish this afternoon for most areas, but scattered
showers should continue over our east and southeast counties
overcast skies persist. Over south-central IN, some breaks in the
clouds could occur later this afternoon.
High temperatures today are tricky. Values at this time may not go
up much if any today. Matter of fact, could see readings fall a bit
as a brisk northeast wind develops along with the low clouds and
showers in parts of central KY. Will keep readings in the upper 50s
over much of east-central KY west-southwestward, with lower-mid 60s
for south-central KY, again with highest values this morning. Also,
expect lower-mid 60s in south-central IN where low clouds will scour
out and showers will end this afternoon. Lows tonight should range
from the mid 40s to lower 50s with a cloudy sky south and east, and
partly to mostly cloudy north and west.
On Wednesday, mid-level flow will begin to back again, resulting in
clouds moving back northward. There could be some scattered showers
especially across south-central KY, although there are no clear
forcing mechanics at this time. Expect highs in the mid 60s to lower
70s.
.LONG TERM (Wednesday Night through Monday)...
Issued at 325 AM EDT Tue Apr 14 2015
...Above Normal Rainfall Expected This Week...
In general terms, there is not a whole lot of change in the guidance
for the extended forecast period. The synoptic flow aloft will be
characterized by a fast northern jet flow confined to the
US/Canadian border region, while a split flow pattern will be in
place across the western US with a cut off low in the southern
stream. Multiple wave packets will eject out of the southern stream
and pass through the region in the mid-late part of the week,
bringing precipitation with the potential for heavy rainfall. By
late in the period, the cut off low over the SW US is expected to
lift out and merge with a northern stream wave which looks to turn
into a rather large gyre over the northern Great Lakes by early next
week. This would bring drier and cooler than normal conditions to
the region.
It does appear that we`ll see the first wave push through the region
on Thursday with a secondary wave coming in Friday night and early
Saturday. Combination of lift with the associated waves and plenty
of Gulf moisture will lead to widespread rainfall, some heavy, which
could result in renewed hydrologic concerns through the period.
This would be especially true across our southern half of the
forecast area...mainly south of the Parkways. The weekend does not
look to be an entire wash out, but Saturday morning will probably
remain a bit unsettled as the aforementioned wave ejects through the
region. There is a growing consensus in the data that upper level
ridging will build in during the afternoon to allow the region to
dry out a bit. Thus, will continue to run chance PoPs in the
forecast for the early part of Saturday and then allow PoPs to
decrease throughout the remainder of the day and into Sunday.
As the upper low out over the southwest US lifts out and combines
with the northern stream wave pushing through, we should see a
return of wet weather as we head into late Sunday and Monday. More
showers with some thunderstorms looks likely.
As for temperatures, have generally stuck close to the SuperBlend
consensus guidance for temperatures. This will result in daytime
highs generally in the upper 60s to the lower 70s for highs and
overnight lows in the 50s. These temperature forecasts will likely
see some sort of modulation in subsequent forecasts as the timing
issues in the upper level waves moving through the area become more
clearly defined in the coming days.
&&
.AVIATION (12Z TAF Update)...
Updated at 645 AM EDT Tue Apr 14 2015
Widespread rain continues this morning, affecting BWG the most with
some IFR ceilings from time to time and reduced visibility in
moderate to heavy rain. LEX ceiling continues to change between IFR
and MVFR, but MVFR should be the prevailing category for much of the
rest of the morning. Expect SDF ceiling to mostly stay VFR, but
can`t rule out MVFR at times this morning.
These conditions will continue for the morning hours with improving
conditions this afternoon at SDF and LEX. However, it is unclear
whether clouds will lift enough for VFR conditions at BWG this
afternoon and tonight. Will keep MVFR as low clouds below 3 kft
should remain. Also, could see at least MVFR visibilities due to fog
early Wednesday morning at BWG.
Expect surface winds from the north-northeast at 10-15 kts with
gusts around or above 20 kts at times this morning into early
afternoon in response to low pressure moving east-northeast across
the TN Valley.
&&
.LMK WATCHES/WARNINGS/ADVISORIES...
KY...FLOOD WATCH until 11 AM EDT /10 AM CDT/ this morning FOR
KYZ040>043-046>049-053>057-061>067-070>078-081-082.
IN...NONE.
&&
$$
Updates........RJS/TWF
Short Term.....TWF
Long Term......MJ
Aviation.......TWF
AREA FORECAST DISCUSSION
NWS LOUISVILLE KY
934 AM EDT Tue Apr 14 2015
...Forecast Update...
Issued at 930 AM EDT Tue Apr 14 2015
Heaviest band of precip has lifted north into southern Indiana, but
continue with moderate rains over our east and southeast counties.
Areal flood warnings are out with several reports of water over
roads coming in for those areas. We should not have such a problem
over the north, but will keep watch over the next hour or two until
the shortwave noted on water vapor imagery kicks out of here and the
forcing for these rains dies down.
Issued at 650 AM EDT Tue Apr 14 2015
Just a quick update on latest trends. Widespread rain continues at
this time over most of central KY as the mid-level shortwave heads
northeast across western TN at this time. Pockets of moderate to
heavy rain are occurring throughout the region. This could cause
significant ponding of water on some roads and low-lying areas, and
some creeks could possibly overflow. However, have received no
reports of flooding at this time.
06z models and latest HRRR reflecting radar trends well. The sharp
northern edge of the rain along and south of the OH River has
relaxed some and spread a bit farther north as expected. A few
heavier rain elements are now showing up near Evansville and just
northeast of Louisville. The heaviest steadiest rains will remain
within the Flood Watch area, but showers will spread northeast
across much of south-central IN over the next hour or two.
Otherwise, forecast is on track with just some tweaks to hourly POPs
to match latest trends.
.SHORT TERM (Now through Wednesday)...
Issued at 315 AM EDT Tue Apr 14 2015
...Flood Watch continues this morning for parts of central KY...
A solid area of rain has evolved in a WSW-ENE axis across central
KY early this morning, ahead of a pronounced shortwave in water
vapor imagery moving from AR/MS into western TN and an associated
surface low pressure system. Within this rain are numerous areas of
moderate rain. At this time, there is a distinct northern boundary
to the rain along and just south of the OH River associated with a
deformation zone. The latest few HRRR runs have shown that rain just
ahead of the shortwave may move a little farther north and be slower
to depart than previous forecasts, which the 00z NAM also hinted at.
These models are slower and farther north than the 00z GFS, which
seems reasonable. Thus, despite the current tight northern precip
edge, more showers should move back across the Louisville metro and
into at least parts of south-central IN later this morning,
continuing during much of the morning. However, the heaviest rain
should continue to fall out in an axis to the east of the shortwave.
The current Flood Watch looks good, although decent rains will fall
a county or so north of the Watch as well, but will keep the area
unchanged at this time. The overall trend should be for more bands
of showers to form east of the shortwave then rotate north and east.
This should keep highest rainfall totals in an axis from about BWG
to LEX and a row of counties or so south. Still looks like 1 to 2
inches of rain is a good bet in this axis, with locally 2+ inches
possible in a few spots. However, since rainfall is not truly
convective and since rain rates should not increase much more than
at present, widespread flash flooding is not likely. Instead,
significant ponding and some areal flooding of roads, low-lying
areas, creeks, and small streams may occur. Slightly lower rain
totals are expected over our extreme southeast south-central KY
counties. While showers will continue past the 15 UTC expiration
time of the Watch, will not change it at this time. This can be
locally extended if need be later this morning pending latest trends
and reports.
Rainfall will diminish this afternoon for most areas, but scattered
showers should continue over our east and southeast counties
overcast skies persist. Over south-central IN, some breaks in the
clouds could occur later this afternoon.
High temperatures today are tricky. Values at this time may not go
up much if any today. Matter of fact, could see readings fall a bit
as a brisk northeast wind develops along with the low clouds and
showers in parts of central KY. Will keep readings in the upper 50s
over much of east-central KY west-southwestward, with lower-mid 60s
for south-central KY, again with highest values this morning. Also,
expect lower-mid 60s in south-central IN where low clouds will scour
out and showers will end this afternoon. Lows tonight should range
from the mid 40s to lower 50s with a cloudy sky south and east, and
partly to mostly cloudy north and west.
On Wednesday, mid-level flow will begin to back again, resulting in
clouds moving back northward. There could be some scattered showers
especially across south-central KY, although there are no clear
forcing mechanics at this time. Expect highs in the mid 60s to lower
70s.
.LONG TERM (Wednesday Night through Monday)...
Issued at 325 AM EDT Tue Apr 14 2015
...Above Normal Rainfall Expected This Week...
In general terms, there is not a whole lot of change in the guidance
for the extended forecast period. The synoptic flow aloft will be
characterized by a fast northern jet flow confined to the
US/Canadian border region, while a split flow pattern will be in
place across the western US with a cut off low in the southern
stream. Multiple wave packets will eject out of the southern stream
and pass through the region in the mid-late part of the week,
bringing precipitation with the potential for heavy rainfall. By
late in the period, the cut off low over the SW US is expected to
lift out and merge with a northern stream wave which looks to turn
into a rather large gyre over the northern Great Lakes by early next
week. This would bring drier and cooler than normal conditions to
the region.
It does appear that we`ll see the first wave push through the region
on Thursday with a secondary wave coming in Friday night and early
Saturday. Combination of lift with the associated waves and plenty
of Gulf moisture will lead to widespread rainfall, some heavy, which
could result in renewed hydrologic concerns through the period.
This would be especially true across our southern half of the
forecast area...mainly south of the Parkways. The weekend does not
look to be an entire wash out, but Saturday morning will probably
remain a bit unsettled as the aforementioned wave ejects through the
region. There is a growing consensus in the data that upper level
ridging will build in during the afternoon to allow the region to
dry out a bit. Thus, will continue to run chance PoPs in the
forecast for the early part of Saturday and then allow PoPs to
decrease throughout the remainder of the day and into Sunday.
As the upper low out over the southwest US lifts out and combines
with the northern stream wave pushing through, we should see a
return of wet weather as we head into late Sunday and Monday. More
showers with some thunderstorms looks likely.
As for temperatures, have generally stuck close to the SuperBlend
consensus guidance for temperatures. This will result in daytime
highs generally in the upper 60s to the lower 70s for highs and
overnight lows in the 50s. These temperature forecasts will likely
see some sort of modulation in subsequent forecasts as the timing
issues in the upper level waves moving through the area become more
clearly defined in the coming days.
&&
.AVIATION (12Z TAF Update)...
Updated at 645 AM EDT Tue Apr 14 2015
Widespread rain continues this morning, affecting BWG the most with
some IFR ceilings from time to time and reduced visibility in
moderate to heavy rain. LEX ceiling continues to change between IFR
and MVFR, but MVFR should be the prevailing category for much of the
rest of the morning. Expect SDF ceiling to mostly stay VFR, but
can`t rule out MVFR at times this morning.
These conditions will continue for the morning hours with improving
conditions this afternoon at SDF and LEX. However, it is unclear
whether clouds will lift enough for VFR conditions at BWG this
afternoon and tonight. Will keep MVFR as low clouds below 3 kft
should remain. Also, could see at least MVFR visibilities due to fog
early Wednesday morning at BWG.
Expect surface winds from the north-northeast at 10-15 kts with
gusts around or above 20 kts at times this morning into early
afternoon in response to low pressure moving east-northeast across
the TN Valley.
&&
.LMK WATCHES/WARNINGS/ADVISORIES...
KY...FLOOD WATCH until 11 AM EDT /10 AM CDT/ this morning FOR
KYZ040>043-046>049-053>057-061>067-070>078-081-082.
IN...NONE.
&&
$$
Updates........RJS/TWF
Short Term.....TWF
Long Term......MJ
Aviation.......TWF
AREA FORECAST DISCUSSION
NWS LOUISVILLE KY
656 AM EDT Tue Apr 14 2015
...Updated Forecast and Aviation Discussions...
...Forecast Update...
Issued at 650 AM EDT Tue Apr 14 2015
Just a quick update on latest trends. Widespread rain continues at
this time over most of central KY as the mid-level shortwave heads
northeast across western TN at this time. Pockets of moderate to
heavy rain are occurring throughout the region. This could cause
significant ponding of water on some roads and low-lying areas, and
some creeks could possibly overflow. However, have received no
reports of flooding at this time.
06z models and latest HRRR reflecting radar trends well. The sharp
northern edge of the rain along and south of the OH River has
relaxed some and spread a bit farther north as expected. A few
heavier rain elements are now showing up near Evansville and just
northeast of Louisville. The heaviest steadiest rains will remain
within the Flood Watch area, but showers will spread northeast
across much of south-central IN over the next hour or two.
Otherwise, forecast is on track with just some tweaks to hourly POPs
to match latest trends.
.SHORT TERM (Now through Wednesday)...
Issued at 315 AM EDT Tue Apr 14 2015
...Flood Watch continues this morning for parts of central KY...
A solid area of rain has evolved in a WSW-ENE axis across central
KY early this morning, ahead of a pronounced shortwave in water
vapor imagery moving from AR/MS into western TN and an associated
surface low pressure system. Within this rain are numerous areas of
moderate rain. At this time, there is a distinct northern boundary
to the rain along and just south of the OH River associated with a
deformation zone. The latest few HRRR runs have shown that rain just
ahead of the shortwave may move a little farther north and be slower
to depart than previous forecasts, which the 00z NAM also hinted at.
These models are slower and farther north than the 00z GFS, which
seems reasonable. Thus, despite the current tight northern precip
edge, more showers should move back across the Louisville metro and
into at least parts of south-central IN later this morning,
continuing during much of the morning. However, the heaviest rain
should continue to fall out in an axis to the east of the shortwave.
The current Flood Watch looks good, although decent rains will fall
a county or so north of the Watch as well, but will keep the area
unchanged at this time. The overall trend should be for more bands
of showers to form east of the shortwave then rotate north and east.
This should keep highest rainfall totals in an axis from about BWG
to LEX and a row of counties or so south. Still looks like 1 to 2
inches of rain is a good bet in this axis, with locally 2+ inches
possible in a few spots. However, since rainfall is not truly
convective and since rain rates should not increase much more than
at present, widespread flash flooding is not likely. Instead,
significant ponding and some areal flooding of roads, low-lying
areas, creeks, and small streams may occur. Slightly lower rain
totals are expected over our extreme southeast south-central KY
counties. While showers will continue past the 15 UTC expiration
time of the Watch, will not change it at this time. This can be
locally extended if need be later this morning pending latest trends
and reports.
Rainfall will diminish this afternoon for most areas, but scattered
showers should continue over our east and southeast counties
overcast skies persist. Over south-central IN, some breaks in the
clouds could occur later this afternoon.
High temperatures today are tricky. Values at this time may not go
up much if any today. Matter of fact, could see readings fall a bit
as a brisk northeast wind develops along with the low clouds and
showers in parts of central KY. Will keep readings in the upper 50s
over much of east-central KY west-southwestward, with lower-mid 60s
for south-central KY, again with highest values this morning. Also,
expect lower-mid 60s in south-central IN where low clouds will scour
out and showers will end this afternoon. Lows tonight should range
from the mid 40s to lower 50s with a cloudy sky south and east, and
partly to mostly cloudy north and west.
On Wednesday, mid-level flow will begin to back again, resulting in
clouds moving back northward. There could be some scattered showers
especially across south-central KY, although there are no clear
forcing mechanics at this time. Expect highs in the mid 60s to lower
70s.
.LONG TERM (Wednesday Night through Monday)...
Issued at 325 AM EDT Tue Apr 14 2015
...Above Normal Rainfall Expected This Week...
In general terms, there is not a whole lot of change in the
guidance for the extended forecast period. The synoptic flow aloft
will be characterized by a fast northern jet flow confined to the
US/Canadian border region, while a split flow pattern will be in
place across the western US with a cut off low in the southern
stream. Multiple wave packets will eject out of the southern
stream and pass through the region in the mid-late part of the
week, bringing precipitation with the potential for heavy
rainfall. By late in the period, the cut off low over the SW US is
expected to lift out and merge with a northern stream wave which
looks to turn into a rather large gyre over the northern Great
Lakes by early next week. This would bring drier and cooler than
normal conditions to the region.
It does appear that we`ll see the first wave push through the region
on Thursday with a secondary wave coming in Friday night and early
Saturday. Combination of lift with the associated waves and plenty
of Gulf moisture will lead to widespread rainfall, some heavy, which
could result in renewed hydrologic concerns through the period.
This would be especially true across our southern half of the
forecast area...mainly south of the Parkways. The weekend does not
look to be an entire wash out, but Saturday morning will probably
remain a bit unsettled as the aforementioned wave ejects through the
region. There is a growing consensus in the data that upper level
ridging will build in during the afternoon to allow the region to
dry out a bit. Thus, will continue to run chance PoPs in the
forecast for the early part of Saturday and then allow PoPs to
decrease throughout the remainder of the day and into Sunday.
As the upper low out over the southwest US lifts out and combines
with the northern stream wave pushing through, we should see a
return of wet weather as we head into late Sunday and Monday. More
showers with some thunderstorms looks likely.
As for temperatures, have generally stuck close to the SuperBlend
consensus guidance for temperatures. This will result in daytime
highs generally in the upper 60s to the lower 70s for highs and
overnight lows in the 50s. These temperature forecasts will likely
see some sort of modulation in subsequent forecasts as the timing
issues in the upper level waves moving through the area become more
clearly defined in the coming days.
&&
.AVIATION (12Z TAF Update)...
Updated at 645 AM EDT Tue Apr 14 2015
Widespread rain continues this morning, affecting BWG the most with
some IFR ceilings from time to time and reduced visibility in
moderate to heavy rain. LEX ceiling continues to change between IFR
and MVFR, but MVFR should be the prevailing category for much of the
rest of the morning. Expect SDF ceiling to mostly stay VFR, but
can`t rule out MVFR at times this morning.
These conditions will continue for the morning hours with improving
conditions this afternoon at SDF and LEX. However, it is unclear
whether clouds will lift enough for VFR conditions at BWG this
afternoon and tonight. Will keep MVFR as low clouds below 3 kft
should remain. Also, could see at least MVFR visibilities due to fog
early Wednesday morning at BWG.
Expect surface winds from the north-northeast at 10-15 kts with
gusts around or above 20 kts at times this morning into early
afternoon in response to low pressure moving east-northeast across
the TN Valley.
&&
.LMK WATCHES/WARNINGS/ADVISORIES...
KY...FLOOD WATCH until 11 AM EDT /10 AM CDT/ this morning FOR
KYZ040>043-046>049-053>057-061>067-070>078-081-082.
IN...NONE.
&&
$$
Update.........TWF
Short Term.....TWF
Long Term......MJ
Aviation.......TWF
AREA FORECAST DISCUSSION
NWS LOUISVILLE KY
327 AM EDT Tue Apr 14 2015
.SHORT TERM (Now through Wednesday)...
Issued at 315 AM EDT Tue Apr 14 2015
...Flood Watch continues this morning for parts of central KY...
A solid area of rain has evolved in a WSW-ENE axis across central
KY early this morning, ahead of a pronounced shortwave in water
vapor imagery moving from AR/MS into western TN and an associated
surface low pressure system. Within this rain are numerous areas of
moderate rain. At this time, there is a distinct northern boundary
to the rain along and just south of the OH River associated with a
deformation zone. The latest few HRRR runs have shown that rain just
ahead of the shortwave may move a little farther north and be slower
to depart than previous forecasts, which the 00z NAM also hinted at.
These models are slower and farther north than the 00z GFS, which
seems reasonable. Thus, despite the current tight northern precip
edge, more showers should move back across the Louisville metro and
into at least parts of south-central IN later this morning,
continuing during much of the morning. However, the heaviest rain
should continue to fall out in an axis to the east of the shortwave.
The current Flood Watch looks good, although decent rains will fall
a county or so north of the Watch as well, but will keep the area
unchanged at this time. The overall trend should be for more bands
of showers to form east of the shortwave then rotate north and east.
This should keep highest rainfall totals in an axis from about BWG
to LEX and a row of counties or so south. Still looks like 1 to 2
inches of rain is a good bet in this axis, with locally 2+ inches
possible in a few spots. However, since rainfall is not truly
convective and since rain rates should not increase much more than
at present, widespread flash flooding is not likely. Instead,
significant ponding and some areal flooding of roads, low-lying
areas, creeks, and small streams may occur. Slightly lower rain
totals are expected over our extreme southeast south-central KY
counties. While showers will continue past the 15 UTC expiration
time of the Watch, will not change it at this time. This can be
locally extended if need be later this morning pending latest trends
and reports.
Rainfall will diminish this afternoon for most areas, but scattered
showers should continue over our east and southeast counties
overcast skies persist. Over south-central IN, some breaks in the
clouds could occur later this afternoon.
High temperatures today are tricky. Values at this time may not go
up much if any today. Matter of fact, could see readings fall a bit
as a brisk northeast wind develops along with the low clouds and
showers in parts of central KY. Will keep readings in the upper 50s
over much of east-central KY west-southwestward, with lower-mid 60s
for south-central KY, again with highest values this morning. Also,
expect lower-mid 60s in south-central IN where low clouds will scour
out and showers will end this afternoon. Lows tonight should range
from the mid 40s to lower 50s with a cloudy sky south and east, and
partly to mostly cloudy north and west.
On Wednesday, mid-level flow will begin to back again, resulting in
clouds moving back northward. There could be some scattered showers
especially across south-central KY, although there are no clear
forcing mechanics at this time. Expect highs in the mid 60s to lower
70s.
.LONG TERM (Wednesday Night through Monday)...
Issued at 325 AM EDT Tue Apr 14 2015
...Above Normal Rainfall Expected This Week...
In general terms, there is not a whole lot of change in the
guidance for the extended forecast period. The synoptic flow aloft
will be characterized by a fast northern jet flow confined to the
US/Canadian border region, while a split flow pattern will be in
place across the western US with a cut off low in the southern
stream. Multiple wave packets will eject out of the southern
stream and pass through the region in the mid-late part of the
week, bringing precipitation with the potential for heavy
rainfall. By late in the period, the cut off low over the SW US is
expected to lift out and merge with a northern stream wave which
looks to turn into a rather large gyre over the northern Great
Lakes by early next week. This would bring drier and cooler than
normal conditions to the region.
It does appear that we`ll see the first wave push through the region
on Thursday with a secondary wave coming in Friday night and early
Saturday. Combination of lift with the associated waves and plenty
of Gulf moisture will lead to widespread rainfall, some heavy, which
could result in renewed hydrologic concerns through the period.
This would be especially true across our southern half of the
forecast area...mainly south of the Parkways. The weekend does not
look to be an entire wash out, but Saturday morning will probably
remain a bit unsettled as the aforementioned wave ejects through the
region. There is a growing consensus in the data that upper level
ridging will build in during the afternoon to allow the region to
dry out a bit. Thus, will continue to run chance PoPs in the
forecast for the early part of Saturday and then allow PoPs to
decrease throughout the remainder of the day and into Sunday.
As the upper low out over the southwest US lifts out and combines
with the northern stream wave pushing through, we should see a
return of wet weather as we head into late Sunday and Monday. More
showers with some thunderstorms looks likely.
As for temperatures, have generally stuck close to the SuperBlend
consensus guidance for temperatures. This will result in daytime
highs generally in the upper 60s to the lower 70s for highs and
overnight lows in the 50s. These temperature forecasts will likely
see some sort of modulation in subsequent forecasts as the timing
issues in the upper level waves moving through the area become more
clearly defined in the coming days.
&&
.AVIATION (06Z TAF Update)...
Updated at 130 AM EDT Tue Apr 14 2015
Rain was increasing across central KY at 0530z ahead of a shortwave
trough over the lower MS Valley that was moving northeast. Ceilings
at the 3 TAF sites have been a bit variable and on the edge of
different flight categories. SDF ceiling is just between MVFR and
VFR, with BWG and LEX going from MVFR to IFR and even LIFR at times.
These same general ceiling values should hold through about 12z,
with values raising a bit thereafter, but BWG and LEX staying MVFR.
Rain will continue to spread northeast overnight and Tuesday
morning. Based on latest radar and shortwave trends, will hold onto
rain showers longer and a little farther north than previously
expected on Tuesday. Surface winds will gradually increase overnight
and especially Tuesday morning from the north-northeast at 10-15 kts
with gusts around 20 kts in response to low pressure moving east-
northeast across the TN Valley.
&&
.LMK WATCHES/WARNINGS/ADVISORIES...
KY...FLOOD WATCH until 11 AM EDT /10 AM CDT/ this morning FOR
KYZ040>043-046>049-053>057-061>067-070>078-081-082.
IN...NONE.
&&
$$
Short Term........TWF
Long Term.........MJ
Aviation..........TWF
AREA FORECAST DISCUSSION
NWS JACKSON KY
159 AM EDT TUE APR 14 2015
.UPDATE...
ISSUED AT 159 AM EDT TUE APR 14 2015
RADAR SHOWS HEAVIER SHOWERS LINING UP IN A BAND FROM RICHMOND
EAST-NORTHEAST THROUGH POWELL...MENIFEE...MORGAN AND ELLIOTT
COUNTIES. AN IFLOWS GAUGE NEAR SANDY HOOK JUST CLICKED OFF 0.52
INCHES OF RAIN IN THE PAST HOUR AND SUCH RATES WILL LIKELY
CONTINUE UNDER THIS BAND FOR SEVERAL HOURS. THIS BAND IS RIGHT
UNDERNEATH THE AXIS OF HIGHEST PWATS AND WILL NEED TO BE MONITORED
CLOSELY FOR FLOODING TO DEVELOP OVER THE NEXT FEW HOURS.
OTHERWISE...JUST PUSHED ALONG AN UPDATE TO ADD PATCHY FOG TO THE
FORECAST FOR THE REST OF THE NIGHT AND INCREASE SKY COVER AND
WINDS TODAY AND TONIGHT TO CORRESPOND WITH THE SCHEDULED AVIATION
UPDATE.
UPDATE ISSUED AT 1050 PM EDT MON APR 13 2015
2Z SPC MESOANALYSIS HAS PW VALUES ACROSS THE AREA RANGING FROM
AROUND 1.3 IN FAR SOUTHEASTERN PIKE COUNTY TO NEAR 1.6 INCHES IN
THE FAR SOUTHWEST. THIS PUTS THE WESTERN THIRD OF THE AREA AT
NEARLY 1.5 INCHES IN ADVANCE OF THE SLOW MOVING COLD FRONT.
RAINFALL RATES IN THE SHOWERS ACROSS THE WESTERN HALF OR SO OF THE
AREA HAVE PICKED UP A BIT OVER THE PAST HOUR WITH NEAR 0.02 INCHES
OVER THE PAST HOUR AT JKL. MANY OF THE KY MESONET SITES IN THE
WESTERN THIRD OF THE CWA NOW HAVE TOTALS SO FAR IN THE THIRD OF AN
INCH TO 0.45 INCH RANGE.
THE RECENT NEAR TERM MODEL GUIDANCE CONTINUES TO POINT TO THE
HIGHEST RAINFALL OVERNIGHT AND THROUGH MIDDAY ON TUESDAY GENERALLY
ALONG AND OR WEST OF A LINE FROM NEAR WILLIAMSBURG TO MANCHESTER
TO HAZARD TO INEZ. THERE IS SOME MODEL VARIABILITY FROM RUN TO RUN
OF THE HRRR AND RAP AS FAR AS AMOUNTS. THE 0Z NAM HAS THE HEAVIEST
QPF THROUGH 18Z ON TUESDAY...AND IS PROBABLY OVERDONE AT LEAST
WITH AREAL COVERAGE. HOWEVER...IT POINTS TO LOCALLY HIGHER
AMOUNTS EXCEEDING 3 INCHES NOT BEING OUT OF THE QUESTION.
ATTM...WE HAVE NUDGED THE AXIS OF THE HEAVIEST QPF A TAD FURTHER
TO THE NORTHWEST. OUR CURRENT FORECAST IS CLOSEST TO THE 01Z RAP.
UPDATE ISSUED AT 715 PM EDT MON APR 13 2015
RECENT SHORT TERM MODEL RUNS OF THE HRRR SUGGEST THE AXIS OF
HEAVIEST RAIN TONIGHT MAY BE GENERALLY ALONG AND NORTH OF A LINE
FROM WILLIAMSBURG TO LONDON TO JACKSON TO INEZ. THE 18Z NAM HAS
THE HEAVIEST RAINFALL THROUGH TOMORROW AFTERNOON WITH THE AXIS OF
THE HEAVIEST RAIN FURTHEST NORTHWEST. THE 18Z GFS IF GENERALLY THE
FURTHEST SOUTHEAST. THE HRRR RUNS CONTINUE TO BE IN THE MIDDLE OF
THESE TWO. THE 12Z ECMWF ALSO HAD THE HEAVIEST RAIN TONIGHT INTO
TUESDAY GENERALLY ALONG OR NORTHWEST OF THE LINE PREVIOUSLY
MENTIONED. THE 21Z AND 22Z RAP RUNS ARE A BIT FURTHER SOUTHEAST
COMPARED TO THE HRRR RUNS. ALTHOUGH THERE IS UNCERTAINTY...AT
THIS TIME RANGE...FEEL THE HIGHER RESOLUTION MODELS ARE LIKELY
ONTO A REAL TREND. WITH THIS IN MIND...THE QPF HAS BEEN TRENDED
SLIGHTLY TOWARD THE RECENT HRRR AND RAP RUNS WHICH SHIFTED THE
AXIS OF HEAVIER RAIN A TOUCH FURTHER WEST AND EXTENDED THIS AXIS
INTO NORTHEASTERN KY THROUGH MORGAN AND INTO ELLIOTT COUNTIES.
AS NEW MODEL RUNS ARRIVE...WE WILL CONTINUE TO EVALUATE THE
PLACEMENT OF THE AXIS OF HEAVIEST RAINFALL.
&&
.SHORT TERM...(THIS EVENING THROUGH TUESDAY NIGHT)
ISSUED AT 335 PM EDT MON APR 13 2015
18Z SFC ANALYSIS SHOWS LOW PRESSURE MOVING CLOSER FROM THE
SOUTHWEST WHILE TO THE NORTH A COLD FRONT IS HEADING THIS WAY...AS
SEEN IN THE RADAR MOSAIC AND ON SATELLITE. JUST RECENTLY A FEW
SHOWERS HAVE POPPED UP OVER THE CUMBERLAND VALLEY AND ARE DRIFTING
NORTH NORTHEAST WHILE A MORE SUBSTANTIAL AREA OF RAIN IS LIFTING
NORTH OUT OF NORTHWEST AND NORTH CENTRAL TENNESSEE. FOR MUCH OF
THE DAY...THE CLOUDS STAYED MAINLY IN THE SOUTHERN PARTS OF THE
CWA ALLOWING THE MOSTLY SUNNY NORTH AND EASTERN PORTIONS TO WARM
INTO THE UPPER 70S AND LOWER 80S THIS AFTERNOON...IN CONTRAST TO
LOW AND MID 70S ATTAINED UNDER THE CLOUDS. DEWPOINTS HAVE COME UP
INTO THE LOWER AND MIDDLE 50S IN THE EAST AND NEAR 60 IN THE
WEST...WHILE WINDS HAVE BEEN SOUTH TO SOUTHWEST AT 10 TO 15 MPH.
THE MODELS ARE NOW IN PRETTY GOOD AGREEMENT ALOFT WITH THE
DYNAMIC SPLIT FLOW PATTERN IN PLACE. A DECENT TROUGH WILL MOVE
THROUGH THE GREAT LAKES IN THE NORTHERN STREAM WHILE A BROAD UPPER
LOW WILL SLIDE EAST THROUGH THE SOUTHERN PLAINS. PLENTY OF ENERGY
WILL SPREAD OVER KENTUCKY FROM THESE TWO SYSTEMS WITH THE SOUTHERN
STREAM ONE THE PRIMARY DRIVER FOR WEATHER THROUGH THE SHORT TERM.
THE NORTHERN TROUGH MOVES EAST BY TUESDAY MORNING AND A WELL
DEFINED MCV CROSSES FROM TENNESSEE INTO KENTUCKY THROUGH THE DAY
ACCOMPANIED BY SOME HEIGHT FALLS AND UPPER LEVEL DIVERGENCE. THE
BULK OF THE MID LEVEL ENERGY WILL LIFT NORTH OF THE STATE TUESDAY
NIGHT WHILE RIDGING HOLDS ON OVER THE SOUTHEAST. GIVEN THE MODEL
AGREEMENT HAVE GONE WITH A MODEL BLEND FOR THE WEATHER DETAILS...
WHILE ALSO LEANING HEAVILY ON THE HIGHER RESOLUTION NAM12 AND HRRR
GIVEN THE SMALL SCALE FEATURES THAT ARE CRITICAL TO THE FORECAST
TONIGHT INTO TUESDAY.
SENSIBLE WEATHER WILL FEATURE A RAPID INCREASE IN THE COVERAGE OF
SHOWERS AND THUNDERSTORMS LATE THIS AFTERNOON AND INTO THE
EVENING...OVER THE WESTERN PARTS OF THE AREA INITIALLY. BY
MIDNIGHT...THOUGH...EXPECT SHOWERS AND THUNDERSTORMS TO COVER MOST
OF THE CWA WITH AREAS OF TRAINING LIKELY SETTING UP. VERY HIGH PW
AIR WILL MOVE OVER EAST KENTUCKY TONIGHT IN CONJUNCTION WITH THE
APPROACH OF THE MCV AND COLD FRONT ADDING TO A THREAT OF EXCESSIVE
RAINS. FLASH FLOODING WILL BE POSSIBILITY FROM THIS...BUT GIVEN
THE DURATION OF THE RAINS...EXPECTED TO LAST INTO AT LEAST MIDDAY
TUESDAY...HAVE DECIDED TO GO WITH A BROADER FLOOD WATCH. THE
FRONT PRESSES FURTHER SOUTH AND THE SFC WAVE MOVES ON OUT OF THE
AREA TUESDAY AFTERNOON LEAVING BEHIND SOME LINGERING...LIGHTER...
SHOWERS ALONG WITH SIGNIFICANTLY COOLER TEMPERATURES THAN TODAY.
THE FRONT TO THE SOUTH WILL THEN START TO WORK BACK NORTH TUESDAY
NIGHT WITH INCREASING CHANCES OF SHOWERS BY DAWN WEDNESDAY.
USED THE SHORTBLEND AS A STARTING POINT FOR THE T/TD/WIND GRIDS
THROUGH THE NEXT 18 TO 24 HOURS WITH THE SUPERBLEND POPULATED FOR
THESE GRIDS THEREAFTER. DID MAKE SOME MINOR...TERRAIN BASED...
ADJUSTMENTS FOR TEMPERATURES EACH NIGHT. AS FOR POPS WENT WITH THE
HIGHER MAV MOS TONIGHT AND THEN A BLEND THROUGH THE REMAINDER OF
THE SHORT TERM PORTION OF THE FORECAST.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 335 PM EDT MON APR 13 2015
LONG TERM PORTION OF THE FORECAST PRESENTS AN ACTIVE PATTERN
ACROSS EASTERN KENTUCKY. CLOSED LOW WILL ESTABLISH ITSELF MUCH OF
THE PERIOD BETWEEN THE SOUTHERN PLAINS TO THE FOUR CORNERS. THIS
WILL RESULT IN SEVERAL WAVES RIDING ALONG THE FLOW FROM SW TO NW.
THESE SUBTLE WAVES WILL PRESENT CHANCES OF SHOWERS AND SOME
THUNDERSTORMS THROUGH THE MUCH OF LONG TERM PERIOD. THIS PATTERN
DOES LOOK TO BREAKDOWN BASED OF THE GFS AS WE MOVE TOWARD THE END
OF THE WEEK INTO THE WEEKEND...AS A UPPER LEVEL LONG WAVE
TROUGH/CLOSED LOW PROGRESSES EAST OUT OF THE WESTERN US DEPENDING
ON WHICH RUN YOU LOOK AT. THIS HOWEVER...IS NOT SUPPORTED BY ALL
THE LONG RANGE GUIDANCE SUCH AS THE 00Z ECMWF...00Z GEM...00Z GFS
ENSEMBLE MEAN SOLUTIONS AT THIS POINT. THESE MODELS KEEP THE
CLOSED LOW ACROSS THE WESTERN US UNTIL WE MOVE INTO EARLY NEXT
WEEK. SHOULD BE SAID THAT BOTH SETUPS WOULD KEEP THE CHANCES OF
SHOWERS AND POSSIBLY THUNDERSTORMS IN THE FORECAST FROM TIME TO
TIME THROUGH MUCH OF THE PERIOD. THE REAL QUESTION IS HOW HIGH
WILL THE CHANCES BE ON A GIVEN DAY...THEREFORE RIGHT NOW WILL LEAN
CLOSE TO THE BLENDED GUIDANCE GIVEN THE UNCERTAINTY THAT EXISTS
WITH THE OVERALL PATTERN LATE IN THE LONG TERM PERIOD. THIS COULD
ALSO HAVE IMPLICATIONS ON TEMPERATURES ESPECIALLY TOWARD THE END
OF THE LONG TERM DEPENDING ON THE PROGRESSION OF THE UPPER LEVEL
PATTERN AND POTENTIAL FOR A COLD FRONT SWINGING THROUGH. AGAIN
THINK IT WILL BE BEST TO STAY CLOSER TO THE BLEND GIVEN THE MORE
UNCERTAIN PATTERN ALOFT. AFTER RELATIVELY COOLER...NEAR TO
SLIGHTLY BELOW NORMAL TEMPS FOR WEDNESDAY AND THURSDAY TEMPS FOR
MUCH OF THE PERIOD WILL BE IN THE LOWER 70S FOR MUCH OF EASTERN
KENTUCKY FOR HIGHS REMAINDER OF LONG TERM.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT)
ISSUED AT 159 AM EDT TUE APR 14 2015
FLIGHT CONDITIONS ARE HIGHLY VARIABLE ACROSS THE AREA EARLY THIS
MORNING BUT EXPECT A GENERAL DECLINE IN CONDITIONS THROUGH DAWN AS
SHOWERS CONTINUE TO FEED NORTHWARD. TAFS SHOULD TREND TOWARD IFR
AT ALL LOCATIONS BY DAWN WITH ONLY A SMALL WINDOW OF IMPROVEMENT
TO MVFR DURING THE LATE AFTERNOON BEFORE DROPPING AGAIN TO THE IFR
LEVELS BY THE END OF THE PERIOD. WINDS WILL START OUT LIGHT BUT
INCREASE DURING THE DAY FROM THE NORTH-NORTHEAST AS AN AREA OF
LOW PRESSURE TRACKS INTO THE CUMBERLAND RIVER VALLEY. THESE HIGHER
WINDS WILL SUBSIDE AGAIN AFTER DARK.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
FLOOD WATCH UNTIL 11 AM EDT THIS MORNING FOR KYZ044-050>052-
058>060-068-069-079-083.
FLOOD WATCH THROUGH THIS AFTERNOON FOR KYZ080-084>088-104-
106>120.
&&
$$
UPDATE...JP/ABE
SHORT TERM...GREIF
LONG TERM...DJ
AVIATION...ABE
AREA FORECAST DISCUSSION
NWS NEW ORLEANS LA
800 AM CDT TUE APR 14 2015
...SOUNDING DISCUSSION...
AS HAS BEEN THE CASE WITH THE AIRMASS THIS WEEK... THE SOUNDING
THIS MORNING DEPICTS ANOTHER VERY MOIST AND UNSTABLE AIRMASS. CAPE
IS HIGH WITH MIXED LAYER AT 3000 J/KG AND MID LEVEL LAPSE RATES
ARE STEEP AT 6.5 C/KM. NOT MUCH SHEAR THOUGH WITH SOUTHWESTERLY
WINDS THROUGHOUT THE PROFILE. THE LOW LEVEL ENVIRONMENT IS
SATURATED TO 925 MB. PW IS 1.88 INCHES... WHICH LIKE YESTERDAY IS
ANOTHER RECORD MAX FOR TODAY IN THE SPC DAILY CLIMATOLOGY. STORMS
TODAY ARE AGAIN VERY EFFICIENT RAIN MAKERS.
KRAUTMANN
&&
.PREV DISCUSSION... /ISSUED 411 AM CDT TUE APR 14 2015/
SHORT TERM...
IF YOU ARE LOOKING FOR A BREAK IN THE RAIN DO NOT HOLD YOUR
BREATH. THE NEXT ROUND OF SHOWERS AND THUNDERSTORMS ARE BEGINNINGTO
DEVELOP TO THE WEST JUST OUTSIDE OF OUR FORECAST AREA. EXPECT
SHOWERS AND THUNDERSTORMS TO CONTINUE TO DEVELOP THROUGH THE
MORNING HOURS AND MOVE OVER THE FORECAST AREA. WITH PRECIPITATBLE
WATER VALUES STILL WELL ABOVE NORMAL...DEEP ONSHORE FLOW AND THE
INSTABILITY FORECAST TO BE AROUND TODAY...EXPECT SHOWERS AND
STORMS TO BE VERY EFFICIENT RAINFALL PRODUCERS. THE STORM
PREDICTION CENTER HIGHLIGHTS PORTIONS OF OUR AREA IN A MARGINAL
RISK FOR SEVERE WEATHER TODAY BUT THE MAIN ISSUE WILL BE THE HEAVY
RAINFALL...THATS NOT TO SAY THAT ONE OR TO STORMS MAY BE STRONG OR
EVEN SEVERE. THE WEATHER PREDICTION CENTER HAS SOUTHEAST LOUISIANA
AND THE MISSISSIPPI GULF COAST IN A SLIGHT RISK FOR EXCESSIVE
RAINFALL. THIS MEANS THAT HEAVY RAINFALL CAN BE EXPECTED IN THE
AREA. AN ADDITIONAL 1 TO 3 INCHES OF RAINFALL IS POSSIBLE TODAY
OVER THE AREA ESPECIALLY IF YOU GET UNDER SOME OF THESE DEEPER
THUNDERSTORMS. HAVE NOT MADE ANY ADJUSTMENTS TO THE FLASH FLOOD
WATCH THE ONLY THING IS THAT IT MIGHT NEED TO BE EXTENDED BUT WILL
ALLOW DAY SHIFT TO SEE HOW CONVECTION EVOLVES TODAY AND WHERE THE
HEAVIEST RAINFALL OCCURS. HAVE NOT MADE MANY CHANGES IN THE SHORT
TERM. 13/MH
LONG TERM...
THIS ACTIVE WET PATTERN CONTINUES IN THE LONG RANGE. EXPECT
ANOTHER ROUND OF RAIN FOR WEDNESDAY AND THURSDAY. MODELS INDICATE
A PRETTY WET FRIDAY AS WELL...IT IS POSSIBLE THAT THE FLASH FLOOD
WATCH THATS IN PLACE TODAY COULD BE IN PLACE THROUGH FRIDAY IF YOU
TAKE MODELS AT FACE VALUE. THERE WILL BE HIGH RAIN CHANCES THROUGH
AT LEAST SATURDAY. BOTH GFS AND ECMWF SHOW THE UPPER LEVEL
TROUGH/LOW FINALLY MOVING OUT LATE THIS WEEKEND...UNTIL THEN RAIN
WILL BE IN THE FORECAST. HAVE CONTINUED THE BLENDED APPROACH FROM
LAST PACKAGE. DIURNAL TEMPERATURE TRENDS TO CONTINUE WITH NOT MUCH MORE
THAN 10-15 DEGREE SPREAD. COULD SEE A LITTLE COOLER OVERNIGHT LOWS BEGINNING
SUNDAY IN THE NORTH IF SOME DRYING WORKS IN AFTER THE UPPER LOW
PULLS OUT ON SUNDAY INTO MONDAY. 13/MH
AVIATION...
THE TAFS ARE GOING TO BE HIGHLY DEPENDENT ON CONVECTIVE
COVERAGE AND TRENDS THROUGH AT LEAST 00Z. SOME EARLY DEVELOPMENTS
ALREADY IN PROXIMITY TO KHUM AND A LARGER CLUSTER OF SHOWERS
APPROACHING KBTR...LIKELY TO BRING VARABLE CIG HEIGHTS AND VSBY THIS
MORNING THOSE LOCATIONS. HRRR MODEL BLOSSOMS PRECIPITATION OVER MUCH
OF THE AREA TO IMPACT ALL TERMINALS PRIOR TO 18Z. 24/RR
MARINE...
A PROLONGED PERIOD OF ONSHORE FLOW IS EXPECTED TO PREVAIL THROUGH
THE WEEKEND...GENERALLY AT LIGHT TO MODERATE LEVELS. A LONG FETCHED
SITUATION FROM THE YUCATAN CHANNEL GENERATES A DEEP SWELL TRAIN ON
FRIDAY THAT SHOULD BRING SEAS CLOSE TO 6 FEET IN THE OPEN
WATERS...WITH SOME 8 FOOT RANDOM WAVES IN THE OUTER WATERS THAT MAY
REQUIRE A SMALL CRAFT ADVISORY AT SOME POINT FRIDAY INTO SATURDAY.
24/RR
DECISION SUPPORT...
DSS CODE...BLUE.
DEPLOYED...NONE
ACTIVATION...NONE
ACTIVITIES...FLASH FLOOD WATCH.
MONITORING HEAVY RAINFALL/FLOODING POTENTIAL.
DECISION SUPPORT SERVICES (DSS) CODE LEGEND
GREEN = NO WEATHER IMPACTS THAT REQUIRE ACTION
BLUE = LONG FUSED WATCH/WARNING/ADVISORY IN EFFECT OR HIGH
VISIBILITY EVENT
YELLOW = HEIGHTENED IMPACTS WITH SHORT FUSED
WATCH/WARNING/ADVISORY ISSUANCES; RADAR SUPPORT
ORANGE = HIGH IMPACTS - SLIGHT TO MODERATE RISK SEVERE; NEARBY
TROPICAL EVENTS; HAZMAT OR OTHER LARGE EPISODES
RED = FULL ENGAGEMENT FOR MODERATE TONIGHT RISK SVR
AND/OR DIRECT TROPICAL THREATS; EVENTS OF NATIONAL
SIGNIFICANCE
&&
.PRELIMINARY POINT TEMPS/POPS...
MCB 77 65 77 66 / 80 40 60 40
BTR 77 66 79 67 / 80 40 60 40
ASD 78 67 79 68 / 80 40 60 40
MSY 78 68 79 69 / 80 40 60 40
GPT 77 69 77 70 / 70 40 60 40
PQL 79 68 79 69 / 70 40 60 50
&&
.LIX WATCHES/WARNINGS/ADVISORIES...
LA...FLASH FLOOD WATCH UNTIL 7 PM CDT THIS EVENING FOR LAZ040-046>050-
056>070-072.
GM...NONE.
MS...FLASH FLOOD WATCH UNTIL 7 PM CDT THIS EVENING FOR MSZ080>082.
GM...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS NEW ORLEANS LA
411 AM CDT TUE APR 14 2015
.SHORT TERM...
IF YOU ARE LOOKING FOR A BREAK IN THE RAIN DO NOT HOLD YOUR
BREATH. THE NEXT ROUND OF SHOWERS AND THUNDERSTORMS ARE BEGINNINGTO
DEVELOP TO THE WEST JUST OUTSIDE OF OUR FORECAST AREA. EXPECT
SHOWERS AND THUNDERSTORMS TO CONTINUE TO DEVELOP THROUGH THE
MORNING HOURS AND MOVE OVER THE FORECAST AREA. WITH PRECIPITATBLE
WATER VALUES STILL WELL ABOVE NORMAL...DEEP ONSHORE FLOW AND THE
INSTABILITY FORECAST TO BE AROUND TODAY...EXPECT SHOWERS AND
STORMS TO BE VERY EFFICIENT RAINFALL PRODUCERS. THE STORM
PREDICTION CENTER HIGHLIGHTS PORTIONS OF OUR AREA IN A MARGINAL
RISK FOR SEVERE WEATHER TODAY BUT THE MAIN ISSUE WILL BE THE HEAVY
RAINFALL...THATS NOT TO SAY THAT ONE OR TO STORMS MAY BE STRONG OR
EVEN SEVERE. THE WEATHER PREDICTION CENTER HAS SOUTHEAST LOUISIANA
AND THE MISSISSIPPI GULF COAST IN A SLIGHT RISK FOR EXCESSIVE
RAINFALL. THIS MEANS THAT HEAVY RAINFALL CAN BE EXPECTED IN THE
AREA. AN ADDITIONAL 1 TO 3 INCHES OF RAINFALL IS POSSIBLE TODAY
OVER THE AREA ESPECIALLY IF YOU GET UNDER SOME OF THESE DEEPER
THUNDERSTORMS. HAVE NOT MADE ANY ADJUSTMENTS TO THE FLASH FLOOD
WATCH THE ONLY THING IS THAT IT MIGHT NEED TO BE EXTENDED BUT WILL
ALLOW DAY SHIFT TO SEE HOW CONVECTION EVOLVES TODAY AND WHERE THE
HEAVIEST RAINFALL OCCURS. HAVE NOT MADE MANY CHANGES IN THE SHORT
TERM. 13/MH
.LONG TERM...
THIS ACTIVE WET PATTERN CONTINUES IN THE LONG RANGE. EXPECT
ANOTHER ROUND OF RAIN FOR WEDNESDAY AND THURSDAY. MODELS INDICATE
A PRETTY WET FRIDAY AS WELL...IT IS POSSIBLE THAT THE FLASH FLOOD
WATCH THATS IN PLACE TODAY COULD BE IN PLACE THROUGH FRIDAY IF YOU
TAKE MODELS AT FACE VALUE. THERE WILL BE HIGH RAIN CHANCES THROUGH
AT LEAST SATURDAY. BOTH GFS AND ECMWF SHOW THE UPPER LEVEL
TROUGH/LOW FINALLY MOVING OUT LATE THIS WEEKEND...UNTIL THEN RAIN
WILL BE IN THE FORECAST. HAVE CONTINUED THE BLENDED APPROACH FROM
LAST PACKAGE. DIURNAL TEMPERATURE TRENDS TO CONTINUE WITH NOT MUCH MORE
THAN 10-15 DEGREE SPREAD. COULD SEE A LITTLE COOLER OVERNIGHT LOWS BEGINNING
SUNDAY IN THE NORTH IF SOME DRYING WORKS IN AFTER THE UPPER LOW
PULLS OUT ON SUNDAY INTO MONDAY. 13/MH
&&
.AVIATION...
THE TAFS ARE GOING TO BE HIGHLY DEPENDENT ON CONVECTIVE
COVERAGE AND TRENDS THROUGH AT LEAST 00Z. SOME EARLY DEVELOPMENTS
ALREADY IN PROXIMITY TO KHUM AND A LARGER CLUSTER OF SHOWERS
APPROACHING KBTR...LIKELY TO BRING VARABLE CIG HEIGHTS AND VSBY THIS
MORNING THOSE LOCATIONS. HRRR MODEL BLOSSOMS PRECIPITATION OVER MUCH
OF THE AREA TO IMPACT ALL TERMINALS PRIOR TO 18Z. 24/RR
&&
.MARINE...
A PROLONGED PERIOD OF ONSHORE FLOW IS EXPECTED TO PREVAIL THROUGH
THE WEEKEND...GENERALLY AT LIGHT TO MODERATE LEVELS. A LONG FETCHED
SITUATION FROM THE YUCATAN CHANNEL GENERATES A DEEP SWELL TRAIN ON
FRIDAY THAT SHOULD BRING SEAS CLOSE TO 6 FEET IN THE OPEN
WATERS...WITH SOME 8 FOOT RANDOM WAVES IN THE OUTER WATERS THAT MAY
REQUIRE A SMALL CRAFT ADVISORY AT SOME POINT FRIDAY INTO SATURDAY.
24/RR
&&
.DECISION SUPPORT...
DSS CODE...BLUE.
DEPLOYED...NONE
ACTIVATION...NONE
ACTIVITIES...FLASH FLOOD WATCH.
MONITORING HEAVY RAINFALL/FLOODING POTENTIAL.
DECISION SUPPORT SERVICES (DSS) CODE LEGEND
GREEN = NO WEATHER IMPACTS THAT REQUIRE ACTION
BLUE = LONG FUSED WATCH/WARNING/ADVISORY IN EFFECT OR HIGH
VISIBILITY EVENT
YELLOW = HEIGHTENED IMPACTS WITH SHORT FUSED
WATCH/WARNING/ADVISORY ISSUANCES; RADAR SUPPORT
ORANGE = HIGH IMPACTS - SLIGHT TO MODERATE RISK SEVERE; NEARBY
TROPICAL EVENTS; HAZMAT OR OTHER LARGE EPISODES
RED = FULL ENGAGEMENT FOR MODERATE TONIGHT RISK SVR
AND/OR DIRECT TROPICAL THREATS; EVENTS OF NATIONAL
SIGNIFICANCE
&&
.PRELIMINARY POINT TEMPS/POPS...
MCB 77 65 77 66 / 80 40 60 40
BTR 77 66 79 67 / 80 40 60 40
ASD 78 67 79 68 / 80 40 60 40
MSY 78 68 79 69 / 80 40 60 40
GPT 77 69 77 70 / 70 40 60 40
PQL 79 68 79 69 / 70 40 60 50
&&
.LIX WATCHES/WARNINGS/ADVISORIES...
LA...FLASH FLOOD WATCH THROUGH THIS EVENING FOR LAZ040-046>050-
056>070-072.
GM...NONE.
MS...FLASH FLOOD WATCH THROUGH THIS EVENING FOR MSZ080>082.
GM...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
203 AM EDT TUE APR 14 2015
.SHORT TERM...(THIS EVENING THROUGH TUESDAY)
ISSUED AT 400 PM EDT MON APR 13 2015
WV IMAGERY AND RUC ANALYSIS INDICATED A MID/UPPER LEVEL TROUGH FROM
NW ONTARIO INTO THE WRN GREAT LAKES. STRONG QVECTOR DIV IN THE WAKE
OF A DEPARTING SHRTWV AND DROPPING 600-500 MB TEMPS HAVE RESULTED IN
A NEARLY DRY ADIABATIC PROFILE AND MIXING HEIGHT TO NEAR 15K FT WITH
GUSTY WNW WINDS ACROSS THE CWA. THE HIGH SFC-600MB LAPSE RATES HAVE
SUPPORTED THE DEVELOPMENT OF SOME ISOLD LIGHT SHOWERS SHOWERS OR
SPRINKLES/VIRGA FROM NW WI INTO SRN UPPER MI. DOWNDRAFTS ASSOCIATED
WITH THE LIGHT SHOWERS MAY ENHANCED THE GUSTY WINDS AS WAS OBSERVED
AT EGV WITH GUSTS TO 45 MPH.
TONIGHT...WITH THE LOSS OF DAYTIME HEATING AND A WEAKENING PRES
GRADIENT...THE GUSTY WINDS AND ISOLD PCPN WILL DIMINISH QUICKLY.
HOWEVER...FCST BOUNDARY LAYER WINDS SHOULD BE STILL STRONG ENOUGH TO
PROVIDE SOME MIXING AND KEEP TEMPS FROM DROPPING OFF TOO FAR WITH
MIN READINGS IN THE LOW TO MID 30S.
TUE...CONFLUENT MID/UPPER LEVEL FLOW AND THE SFC RIDGE WILL BUILD
OVER THE REGION BRINGING SUNNY SKIES AND DRY CONDITIONS. MIXING TO
AROUND 5K-6K FT OR 800 MB WILL SUPPORT HIGHS FROM THE UPPER 50S EAST
TO THE MID 60S SOUTH AND WEST. DEWPOINTS DROPPING INTO THE 10F-15F
RANGE WILL RESULT IN RH VALUES AROUND 15 PCT OVER THE CNTRL AND WEST.
.LONG TERM...(TUESDAY NIGHT THROUGH MONDAY)
ISSUED AT 353 PM EDT MON APR 13 2015
DRY CONDITIONS WILL CONTINUE FOR TUESDAY NIGHT THROUGH
WEDNESDAY...WITH A RIDGE OF HIGH PRESSURE BUILDING AT AT 500MB AND
LINGERING AT THE SFC. WITH PW VALUES AROUND 0.25IN OR LESS AROUND
DAYBREAK WEDNESDAY OVER THE E THIRD OF UPPER MI...FELT REASONABLE TO
LOWER THE MIN TEMPS FOR THE TRADITIONAL COLD SPOTS WEDNESDAY
MORNING TO RIGHT AROUND 30F.
THE APEX OF THE 500MB RIDGE WILL BE OVERHEAD WEDNESDAY
AFTERNOON...AHEAD OF A BROAD TROUGH NEARING FROM S CENTRAL CANADA.
DRY WEATHER WILL CONTINUE THE HIGHER FIRE WEATHER CONCERNS FOR FAR W
AND FAR S CENTRAL UPPER MI /S OF A LINE FROM IMT TO ISQ/. THIS WILL
BE WHERE RH VALUES IN THE UPPER TEENS COMBINE WITH TEMPS AROUND 15F
ABOVE NORMAL. ON A POSITIVE NOTE...WINDS WILL BE FAIRLY LIGHT S
CENTRAL. LOOKING AT THE FCST SOUNDINGS ANYTHING ABOVE 15KTS WOULD BE
ABOVE 400MB...OR AFTER 21Z CLOSER TO THE SFC. PW VALUES OVER THE E
HALF REMAIN AROUND 0.25IN OR LESS /DRIEST OF THE NAM SOLUTION/. OVER
THE FAR W...CLOSER TO THE NEARING LOW...S WINDS COULD GUSTS NEAR 15-
20KTS DURING THE MID TO LATE AFTERNOON HOURS.
AT THE SFC...LOOK FOR AN AREA OF LOW PRESSURE STRETCHING FROM THE S
SASKATCHEWAN/MANITOBA BORDER DOWN THROUGH E CO EARLY WEDNESDAY
MORNING TO DIVIDE INTO 2 SEPARATE SYSTEMS. THE S LOW WILL SINK INTO
TX WEDNESDAY/WEDNESDAY NIGHT WHILE THE N LOW HEADS NE INTO HUDSON
BAY THURSDAY MORNING. EXPECT THE STEADY STATE SFC RIDGE ACROSS UPPER
MI TO SLOWLY WEAKEN WEDNESDAY NIGHT/THURSDAY AS A RESULT OF THE
NEARING LOW. THE BROAD S CENTRAL CANADIAN TROUGH WILL MOVE OVER THE
UPPER GREAT LAKES FOR THE LATTER HALF OF THE WORK WEEK. THURSDAY
AFTERNOON WILL BRING A COLD FRONT STRETCHING FROM THE S HUDSON BAY
LOW THROUGH N MN. IT TENDS TO WASHOUT A BIT AS IT NEARS THE AREA.
WEDNESDAY NIGHT/THURSDAY MORNING WILL HAVE S-SSW WINDS JUST ABOVE
THE SFC /900-950MB/ OF 30-35KTS. SHOULD HAVE ENOUGH OF AN INVERSION
SET UP TO KEEP THESE WINDS FROM BEING REALIZED...WITH AROUND A 5-
10KT PUFF AT THE SFC.
THE 13/00Z RUN OF THE ECMWF IS MORE AGGRESSIVE/STRONGER WITH THE COLD
FRONT...WITH SIGHT SHOWERS THURSDAY MORNING AND W-NW WINDS SLIDING
IN LATE THURSDAY AFTERNOON/EVENING WITH 850MB TEMPS FALLING TO
AROUND 2C BY 06Z FRIDAY. BY CONTRAST THE 13/12Z GFS STILL HAS S FLOW
AND 850MB TEMPS AROUND 7C...AND REMAINS DRY. EXPECT HIGH CLOUDS
SLOWLY LOWERING THROUGH THE DAY...BUT AM NOT TOO EXCITED ABOUT ANY
CHANCE OF PRECIP IN OUR MAINLY DRY PATTERN. THE DIFFERENCES BETWEEN
THE GFS AND ECMWF CONTINUE TO WIDEN AS WE MOVE THROUGH THE WEEKEND.
THE NEXT FEATURE OF INTEREST LOOKS TO BE A SHORTWAVE NEARING IN THE
NW FLOW FROM S MANITOBA/NW MN FRIDAY AFTERNOON TO LAKE
SUPERIOR/UPPER MI FRIDAY EVENING. THE GFS IS STRONGER AND DEEPER
WITH THE SYSTEM...WITH A 996MB SFC LOW NEAR JAMES BAY BY 06Z
SATURDAY...AND PUMPS UP ADDITIONAL MOISTURE FROM THE 500MB LOW
EJECTING OUT OF THE SW STATES. THE ECMWF IS HOVERING AROUND
1007MB...TRACKING THE LOW OVER E LAKE SUPERIOR AND SE ONTARIO...AND
IS RUNNING INDEPENDENT OF THE S LOW SPINNING AROUND THE 4 CORNERS
REGION.
WITHOUT A LOT OF FANFARE...THE 13/00Z ECMWF MERGES THIS 4 CORNERS
LOW BACK INTO THE NEXT WAVE SINKING ACROSS MT AND THE PLAINS STATES
ON SUNDAY. THE RESULT WOULD BE PRECIP NEARING AGAIN FOR MONDAY ON E-
SE WINDS AND 850MB TEMPS AROUND 3C. THE 12Z RUN IS A LITTLE SLOWER
AND KEEPS PRECIP OUT OF THE CWA UNTIL MONDAY AFTERNOON W.
THE GFS KEEPS THE N AND S STREAMS A BIT MORE SEPARATED. AT 12Z
SUNDAY SFC LOWS OVER SW ONTARIO AND AR SLOWLY MERGE 12Z MONDAY
ACROSS LAKE HURON. PRECIP LOOKS TO SKIP UPPER MI UNTIL -10C AIR
PUSHES IN FROM THE NW ON MONDAY. SO THE MAIN QUESTION IS...WILL OUR
NEXT CHANCE OF ANY REAL PRECIP BE FRIDAY AFTERNOON/EVENING AS THE
GFS BELIEVES...OR WILL IT HOLD OFF UNTIL EARLY NEXT WEEK LIKE THE
ECMWF. WILL LOOK AT THE ENSEMBLE FCSTS...AND A GENERAL BLEND MAY BE
THE WAY TO GO FOR WEDNESDAY NIGHT THROUGH NEXT MONDAY.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT)
ISSUED AT 201 AM EDT TUE APR 14 2015
VFR CONDITIONS WILL CONTINUE THROUGH THE FORECAST PERIOD AT ALL
SITES WITH QUIET WEATHER EXPECTED. SAW GETS A LAKE BREEZE TO MOVE
THROUGH BY MID AFTERNOON WHICH SHOULD SWITCH THEIR WIND TO THE
NORTHEAST UNTIL SUNSET WITH LIGHT WINDS THEREAFTER.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 400 PM EDT MON APR 13 2015
AS THE PRES GRADIENT WEAKENS THIS EVENING...EXPECT THE GUSTY WRLY
WINDS OF 20 TO 30 KNOTS TO FALL BELOW 25 KNOTS. HIGH PRES BUILDING
OVER THE AREA LATE TONIGHT AND TUE WILL KEEP WINDS BLO 20 KNOTS.
WINDS ARE EXPECTED TO REMAIN AT OR BELOW 25 KNOTS THROUGH SATURDAY.
&&
.HYDROLOGY...
ISSUED AT 353 PM EDT MON APR 13 2015
WILL CONTINUE TO MONITOR MELTING SNOW AND RUNOFF FROM THE AVERAGE
0.25IN OF RAIN THAT FELL THIS MORNING. WHILE MOST LOCATIONS HAVE
ONLY PATCHES OF SNOW LEFT...A FEW SPOTS STILL HAVE SIGNIFICANT SNOW
/MOHAWK WITH 17IN AND MUNISING WITH 19IN/. THE FORECAST GETS A BIT
TRICKY FROM WEDNESDAY NIGHT ON...BUT UNTIL THEN NO ADDITIONAL PRECIP
IS EXPECTED.
DAY SHIFT ISSUED A HYDROLOGICAL STATEMENT /RVS/ FOR PRICKETT DAM ON
THE STURGEON RIVER...WHICH WAS AT 7.1FT AT 10AM MONDAY. FLOOD STAGE
IS 8 FT THERE.
ALONG WITH THE SURGEON RIVER OF BARAGA AND HOUGHTON COUNTIES...THE
ESCANABA RIVER WILL ALSO APPROACH BANKFULL STAGE IN SOME SPOTS MID-
WEEK...WHICH MAKES SENSE GIVEN THAT THE HEADWATERS OF THESE RIVER
HAVE THE MOST SNOW. THE MICHIGAMME RIVER ALSO HAS GREATER SNOWPACK
IN THE HEADWATERS REGION OF THE PESHEKEE RIVER...BUT IT SHOULD TAKE
LONGER FOR THAT WATER TO REACH LOWER SECTIONS OF THE RIVER MORE
PRONE TO FLOODING. STILL...NOT SEEING ANYTHING SUGGESTING MORE THAN
ACTION STAGE POSSIBLE ON THE MICHIGAMME RIVER. OVERALL...NOT
EXPECTING SIGNIFICANT FLOODING THROUGH THE WORK WEEK.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...JLB
LONG TERM...KF
AVIATION...07
MARINE...JLB
HYDROLOGY...KF
AREA FORECAST DISCUSSION
NWS KANSAS CITY/PLEASANT HILL MO
316 PM CDT Tue Apr 14 2015
.DISCUSSION...
Issued at 316 PM CDT TUE APR 14 2015
A slow moving upper-level low is meandering northeast through Kansas
based on latest satellite and radar imagery. This is resulting in
isolated to scattered showers over southern Missouri to
slowly lift northward. This trend will continue tonight and arranged
PoPs to build north from late this afternoon through the overnight.
Chances still look rather low and have kept PoPs below 30% through
the night and into the day Wednesday. Short-range higher resolution
models, like the WRF-ARW and NMM as well as the RUC and HRRR all show
relatively spotty shower activity through the night. But overall,
isolated to scattered showers are expected to build northward tonight
and then shift east through the day tomorrow as the upper-level low
opens up and moves away to the east.
The focus will then shift to the large upper-level trough building
into the Intermountain West. First, there is considerable
uncertainty with how this system will evolve and this is mainly due
to the potential for it to cut off and get stuck between the polar
jet to the north and the subtropical jet to the south. This is the
scenario the ECMWF and the GEM depict. However, GFS is not as strong
with the cutting off and as a result pushes east quicker. That said,
it looks like this system will remain to our west through at least
the end of the week, and possibly into the early part of next week,
allowing for southerly low-level flow to build moisture northward.
This means we`ll see the chances for showers and thunderstorms
through much, if not all of, the extended portion of the forecast.
It doesn`t look like we`ll see any widespread precipitation on any
given day, rather isolated to scattered showers and storms.
Additionally, the threat of severe weather looks low for our area as
there never really seems to be aligning of instability with
stronger shear.
Regarding temperatures, with increased cloud coverage/ precipitation
potential for each day, highs look to be fairly close to normal with
temperatures in the upper 60s to lower 70s. Later in the period, as
the upper low is expected to be closer to the region, temperatures
may top out in the mid to upper 60s. The normal high for the Kansas
City area through this period is in the upper 60s.
&&
.AVIATION...(For the 18Z TAFS through 18Z Wednesday Afternoon)
Issued at 1159 AM CDT TUE APR 14 2015
VFR conditions will prevail through the afternoon hours as surface
high pressure exits the area. Overnight, building cloud cover and
light precipitation will develop ahead of a closed low to the
southwest. This will linger through the remainder of the forecast
period as the low center slowly moves north. Ceilings may become MVFR
at times as this system works its way through the area. Winds will
generally stay out of the southeast between 5-8 kts.
&&
.EAX WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
MO...NONE.
&&
$$
DISCUSSION...CDB
AVIATION...Welsh
AREA FORECAST DISCUSSION
NWS BILLINGS MT
313 PM MDT TUE APR 14 2015
.SHORT TERM...VALID FOR WED AND THU...
THE NEXT 24 HOURS WILL HAVE UNSEASONABLE WARMTH...CRITICAL FIRE
WEATHER CONDITIONS...A LOW-END CHANCE OF A THUNDERSTORM...WINDS
GUSTING OVER 50 MPH...AND FINALLY SNOW. SPRINGTIME AT ITS BEST.
AS OF 3 PM MDT...DEEPENING MIXING IS YIELDING RED FLAG CONDITIONS
ACROSS MUCH OF THE AREA AND THIS WILL CONTINUE INTO THIS EVENING.
THE MUCH-ADVERTISED STRONG COLD FRONT IS GAINING STEAM AND HAS
JUST PASSED BOZEMAN. MULTI-RUN HRRR SIMULATIONS AND OTHER 12 UTC
HIGH-RESOLUTION AND EVEN GLOBAL MODEL GUIDANCE SUGGESTS THE FRONT
WILL PASS THROUGH LIVINGSTON BY LATE AFTERNOON...BILLINGS BETWEEN
6 AND 8 PM MDT...SHERIDAN AND MILES CITY BETWEEN 9 PM AND 11 PM
MDT...AND FINALLY BAKER AND EKALAKA BETWEEN 1 AM AND 3 AM MDT. WE
EXPECT STRONG POST-FRONTAL NORTHWEST WINDS BEHIND THE FRONT GIVEN
STRONG LOW-LEVEL COLD AIR ADVECTION AND PRESSURE RISES. THE SNAP-
EFFECT SEEN IN MODELED 850-MB ISOTHERMS WITH A FRONTAL PASSAGE IS
OFTEN A GOOD SIGNATURE OF 40+ MPH GUSTS AND GIVEN THE STRENGTH OF
THE ISOTHERM PACKING IN THIS SCENARIO GUSTS SHOULD BE QUITE A BIT
HIGHER THAN THAT. HRRR WIND GUST SIMULATIONS KEEP SPEEDS UNDER 60
MPH SO WE HAVE REFRAINED FROM ISSUING A HIGH WIND WARNING AT THIS
JUNCTURE...BUT WE HAVE GUSTS TO 55 MPH IN OUR FORECAST AND WE ARE
EXPECTING THIS TO BE A DRAMATIC CHANGE WITH POTENTIAL IMPACTS TO
CONSTRUCTION SITES AND OTHER SPRING PROJECTS. THUS...WE WILL BE
MESSAGING THE STRONG WINDS TO THE PUBLIC AND OUR PARTNERS AND IF
LATER TRENDS SUGGEST EVEN STRONGER WINDS WE MIGHT STILL NEED TO
ISSUE A HIGH WIND WARNING OVER PARTS OF THE AREA FOR THE EVENING.
THE BOUNDARY LAYER IS TOO DRY TO SUPPORT MUCH BUOYANCY DESPITE
ITS STEEP LAPSE RATES...SO WE ARE EXPECTING ALL OF THE RAIN AND
SNOW TO BE POST-FRONTAL. SHOWERS WILL FILL IN BEHIND THE FRONT AS
FORCING FOR ASCENT INCREASES ALOFT AND A THUNDERSTORM IS POSSIBLE
AS WELL THIS EVENING GIVEN STEEP MID-LEVEL LAPSE RATES...BUT WE
FEEL THE PROBABILITY OF MORE THAN A SHORT-LIVED STORM IS RATHER
LOW. CONVECTIVE OUTFLOW COULD ALSO ENHANCE WINDS...EVEN IF IT IS
MAINLY IN THE FORM OF NON-THUNDER-SHOWERS...BUT GUIDANCE SUGGESTS
THERE WILL BE A LAG BEHIND THE LOW-LEVEL FRONTAL SURGE AND SHOWER
DEVELOPMENT /WHICH IS REASONABLE GIVEN THE ANTECEDENT DRY AIR
MASS/. THUS...OUTFLOW MAY NOT HAVE MUCH ADDITIONAL IMPACT ON
INCREASING WINDS THAN IF SHOWERS FORMED RIGHT ON THE FRONT. WE
WILL WATCH RADAR TRENDS TO SEE IF THEY DO MANAGE TO FORM CLOSE TO
THE SURFACE FRONTAL SURGE THOUGH...WHICH COULD TIP THE SCALES TO A
MORE BONAFIDE HIGH WIND EVENT.
REGARDLESS...SHOWERS WILL LIKELY FILL IN OVER SOUTH CENTRAL MT AND
NORTH CENTRAL WY OVERNIGHT AND LINGER INTO WEDNESDAY AND WE STILL
EXPECT A QUICK CHANGE-OVER TO SNOW. A FEW INCHES OF WET SNOW WILL
LIKELY ACCUMULATE IN AND NEAR THE FOOTHILLS AND SO WE HAVE WINTER
WEATHER ADVISORIES IN PLACE THERE. WE ALSO ADDED A WINTER WEATHER
ADVISORY INTO SOUTHERN BIG HORN AND SHERIDAN COUNTIES SINCE THOSE
AREAS WILL LIKELY RECEIVE SOME UPSLOPE ENHANCEMENT TO SNOWFALL. WE
AGAIN LEANED TOWARD THE SOMEWHAT DRIER SIDE OF MODEL OUTPUT TODAY.
HOWEVER...THERE IS ENOUGH CONSISTENCY IN EVEN THE DRIER AND LIKELY
MORE REALISTIC MODEL SOLUTIONS FOR US TO EXPECT SOME ACCUMULATIONS
OF WET SNOW OVER PARTS OF THE AREA. ROADS COULD HAVE SOME IMPACTS
LATE TONIGHT AND WEDNESDAY MORNING WHERE IT SNOWS THE HARDEST OVER
THE FOOTHILLS TOO...BUT OTHER SPOTS AWAY FROM THE FOOTHILLS WHERE
PRECIPITATION INTENSITY IS LIKELY TO BE LESS WILL LIKELY ONLY GET
SNOWFALL ON GRASSY SURFACES. THAT WOULD INCLUDE BILLINGS...WHERE
WE HAVE 1 TO MAYBE 2 INCHES OF SNOW IN THE OFFICIAL FORECAST WITH
THE IDEA THAT ROADS WILL ONLY BE WET EVEN IF IT DOES SNOW AS
FORECAST.
FINALLY...WE COMPLETELY SET ASIDE THE 12 UTC GFS SOLUTION HEADING
INTO WEDNESDAY AND THURSDAY SINCE IT IS A DISTINCT OUTLIER FROM
ALL OTHER MODEL OUTPUT IN CLOSING OFF A SEPARATE...NORTHERN-STREAM
CLOSED MID- AND UPPER-LEVEL LOW IN NORTHEAST WY AND NORTHWEST SD
BY WEDNESDAY EVENING. THAT SIMULATION ACTUALLY YIELDS VERY HEAVY
AND WET SNOW OVER SOUTHEASTERN MT...BUT AGAIN WE HAVE DISCOUNTED
THAT POSSIBILITY FOR NOW SINCE IT HAS NO SUPPORT IN OTHER MODEL
GUIDANCE. SOUTHEASTERN MT MAY WELL GET SOME LIGHT RAIN OR SNOW AS
SHOWN EVEN IN THE PREFERRED 12 UTC NAM AND ECMWF SOLUTIONS...BUT
WE DON/T FORESEE A WARNING-LEVEL EVENT IN THAT AREA LIKE THE GFS
WOULD HAVE US BELIEVE. SCHULTZ
.LONG TERM...VALID FOR FRI...SAT...SUN...MON...TUE...
MODELS ARE NOT IN THE BEST AGREEMENT FRIDAY AS THEY ARE STILL
TRYING TO RESOLVE DIFFERENCES FROM THE WEDNESDAY/THURSDAY STORM
SYSTEM MOVING OUT OF THE CENTRAL AND NORTHERN ROCKIES. BUT IN
GENERAL...CONDITIONS LOOK TO BE DRY BUT DIFFERENCES IN THE UPPER
LEVEL FLOW ARE RESULTING IN AFTERNOON TEMPERATURE DISCREPANCIES.
AS A RESULT...WILL TAKE A BLEND OF THE MODELS KEEPING READINGS IN
THE LOWER TO MIDDLE 60S FOR NOW.
SATURDAY INTO SUNDAY...LEE-SIDE TROUGHING SETS UP FRIDAY NIGHT
CONTINUING INTO SATURDAY AHEAD OF ANOTHER COLD FRONT THAT WILL
SWEEP ACROSS THE FORECAST AREA DURING THE AFTERNOON. SATURDAY
LOOKS TO BE THE WARMEST DAY IN THE EXTENDED DUE TO PRE-FRONTAL
WARMING. EXPECT GUSTY NORTHWEST WINDS TO USHER IN BEHIND THE FRONT
SATURDAY NIGHT INTO SUNDAY. THE FRONT WILL BRING A QUICK SHOT OF
SHOWERS WITH THE HIGHEST CHANCES ALONG THE BEARTOOTH/ABSAROKA
FOOTHILLS SOUTHEAST TO THE BIG HORN FOOTHILLS...AS WELL AS FAVORED
UPSLOPE AREAS OF SOUTHERN BIG HORN COUNTY EAST AND SOUTH INTO
POWDER RIVER AND SHERIDAN COUNTIES.
SUNDAY INTO EARLY NEXT WEEK...A LARGE UPPER LOW OVER THE HUDSON
BAY AREA WILL RESULT IN A CYCLONIC FLOW ACROSS THE EASTERN HALF
OF MONTANA. THIS WILL BRING THE POSSIBILITY OF REINFORCING COLD
FRONTS SOUTH OUT OF CANADA ACROSS THE FORECAST AREA ESPECIALLY
EAST TOWARD THE DAKOTA BORDERS. OVERALL...AFTER SUNDAY...SHOWER
CHANCES WILL BE MINIMAL WITH TEMPERATURES AROUND NORMAL FOR THIS
TIME OF YEAR. HOOLEY
&&
.AVIATION...
A STRONG COLD FRONT WILL MOVE ACROSS THE FORECAST AREA THIS
EVENING INTO THE EARLY MORNING HOURS LATE TONIGHT. THE FRONT IS
EXPECTED TO MOVE THROUGH KLVM AROUND 22Z...KBIL AROUND 01Z...KMLS
AROUND 05Z AND FAR SOUTHEAST MONTANA BY 09Z. ISOLATED SHOWERS
ALONG WITH THE POSSIBILITY OF A THUNDERSTORM CAN BE EXPECTED ALONG
THE FRONT. EXPECT SOUTHWEST TO WEST WIND GUSTS AROUND 50 MPH ALONG
THE FRONT AS WELL. THE PRECIPITATION WILL CHANGE TO ALL SNOW LATE
TONIGHT RESULTING IN LOWERING CEILINGS AND VISIBILITIES OF
MVFR/IFR BY 12Z WEDNESDAY MAINLY ALONG AND WEST OF A KSHR-KBIL
LINE. SURFACE WINDS WILL BECOME NORTHWEST 35-45 KTS BEHIND THE
FRONT. THE MOUNTAINS WILL BE OBSCURED THROUGHOUT THE NIGHT. HOOLEY
&&
.PRELIMINARY POINT TEMP/POPS...
WED THU FRI SAT SUN MON TUE
-----------------------------------------------------------
BIL 036/046 031/059 036/064 041/067 039/057 035/060 039/063
86/W 10/U 00/U 02/W 22/W 21/B 12/W
LVM 032/045 025/058 034/065 038/064 034/055 032/059 036/061
95/W 00/U 00/U 02/W 23/W 21/B 12/W
HDN 036/046 030/060 035/066 037/070 036/059 033/061 035/063
88/W 20/B 00/U 01/B 32/W 21/B 12/W
MLS 042/049 032/061 036/067 040/070 037/058 033/059 035/057
47/W 30/U 00/U 01/U 23/W 11/B 11/B
4BQ 039/044 032/055 032/065 037/070 036/057 032/058 034/059
38/W 51/B 00/U 01/U 33/W 11/B 11/B
BHK 041/051 033/059 033/065 036/069 035/056 031/056 032/053
26/W 41/B 00/U 01/U 33/W 11/B 11/B
SHR 035/038 029/054 031/061 035/067 034/054 031/057 034/060
79/J 51/B 00/U 01/B 43/W 22/W 22/W
&&
.BYZ WATCHES/WARNINGS/ADVISORIES...
MT...RED FLAG WARNING IN EFFECT UNTIL 10 PM MDT THIS EVENING BELOW
6000 FEET FOR ZONES 28-34-39>41-56-63>68.
RED FLAG WARNING IN EFFECT UNTIL 10 PM MDT THIS EVENING FOR
ZONES 29>33-35>38-42-57-58.
WINTER WEATHER ADVISORY IN EFFECT FROM MIDNIGHT TONIGHT TO
MIDNIGHT MDT WEDNESDAY NIGHT FOR ZONE 38.
WINTER WEATHER ADVISORY IN EFFECT FROM 9 PM THIS EVENING TO 6
PM MDT WEDNESDAY FOR ZONES 40-56-64>66.
WY...RED FLAG WARNING IN EFFECT UNTIL 10 PM MDT THIS EVENING FOR
ZONES 98-99.
WINTER WEATHER ADVISORY IN EFFECT FROM MIDNIGHT TONIGHT TO
MIDNIGHT MDT WEDNESDAY NIGHT FOR ZONES 98-99.
&&
$$
WEATHER.GOV/BILLINGS
AREA FORECAST DISCUSSION
NWS OMAHA/VALLEY NE
627 PM CDT WED APR 15 2015
.SHORT TERM...(TONIGHT)
ISSUED AT 309 PM CDT WED APR 15 2015
LARGE SCALE PATTERN PER WV IMAGERY THIS AFTN SHOWING FAST ZONAL FLOW
WITH SEVERAL EMBEDDED WAVES EXTENDING ACROSS SRN CANADA WITH A LARGE
CLOSED OFF CIRCULATION SITUATED OVER THE GREAT BASIN. AT THE
SFC...LLVL MOISTURE RETURN IS UNDERWAY WITH DEW POINTS INCREASING
OVER THE LOWER/MID MS VLY REGION. RUC13 SHOWING BNDRY LYR MOISTURE
ADV CONTINUING THRU TONIGHT WITH PW VALUES INCREASING TO AROUND AN
INCH OVER THE CWA. TSTM DEVELOPMENT PROGGED TO OCCUR OVER CNTRL KS/S-
CNTRL NEB LATER THIS EVENING WITHIN AREA OF ELEVATED
INSTABILITY/NOSE OF LLVL JET...THEN EXPAND NEWD INTO THE WRN CWA
SOMETIME AFT MIDNIGHT AS UPGLIDE INCREASES ALONG 300K SFC. PLAN ON
ONLY MAKING MINOR TWEAKS AT THIS POINT AS GOING FCST IS IN DECENT
SHAPE DEPICTING POPS INCREASING FROM WEST TO EAST DURING THE
OVERNIGHT HOURS.
.LONG TERM...(THURSDAY THROUGH WEDNESDAY)
ISSUED AT 309 PM CDT WED APR 15 2015
MAIN FORECAST CONCERN WILL BE PROGRESSION OF WESTERN CONUS UPPER LOW
AND ITS IMPACTS AS IT SLIDE ACROSS THE CENTRAL PLAINS.
BY THURSDAY MORNING...THE WESTERN CONUS UPPER LOW WILL BE CENTERED
ON TOP OF THE FOUR CORNERS REGION. LEE SIDE SFC LOW REFLECTION IS
FORECAST TO BE FAIRLY BROAD ACROSS THE TEXAS PANHANDLE WITH AN
INVERTED TROUGH EXTENDING NORTHEAST ACROSS WESTERN KS AND INTO
WESTERN NEBRASKA. PRECIPITATION WILL CONTINUE TO SPREAD EAST INTO
OUR WESTERN CWA...BECOMING LIKELY LATER IN THE DAY THURSDAY AS
BROAD SCALE ASCENT INCREASES WITH LEAD SHORTWAVE ENERGY. THE UPPER
LOW WILL SLOWLY MOVE INTO THE SOUTHERN PLAINS AND IS FORECAST TO
OPEN UP THROUGH THE WEEKEND PROVIDING CONTINUED BROAD SCALE
VERTICAL MOTION THROUGH SUNDAY. LOW LEVEL MOISTURE ALREADY IN
PLACE ACROSS THE SOUTHERN PLAINS WILL CONTINUE TO STREAM NORTHWARD
AS THE SFC LOW PRESSURE CENTER BETTER ORGANIZES ACROSS EASTERN
COLORADO BY FRIDAY MORNING. PW`S WILL REMAIN ABOVE 1" THROUGH THE
PERIOD. ALTHOUGH RAIN IS LIKELY AT TIMES THROUGH SUNDAY...WE WILL
HAVE A FEW INTERMITTENT BREAKS BUT TOO DIFFICULT TO DETERMINE AT
THIS POINT WITH SUCH SLOW PROGRESSION OF THE UPPER LOW. BEST
CHANCE FOR THUNDERSTORMS LOOKS TO BE THURSDAY AND FRIDAY
AFTERNOON...ESPECIALLY ACROSS THE SOUTHERN CWA. HAVE INCLUDED
ISOLATED THUNDER MENTION THROUGH MUCH OF THE TIME PERIOD.
BY MID DAY SUNDAY...THE UPPER TROUGH AXIS SHOULD BE EAST OF THE
CWA...ALLOWING PCPN TO END FROM WEST TO EAST. THE 12Z ECMWF REALLY
WRAPS THIS SYSTEM UP...WITH NORTHWESTERLY 850MB WINDS ON THE
ORDER OF 65KTS SUNDAY AFTERNOON. 850MB TEMPERATURES DO APPROACH
THE 0C MARK OF THE LATEST ECMWF SO WILL NEED TO WATCH THAT
CAREFULLY FOR ANY CHANGE OVER IN PCPN TYPES SUNDAY.
MUCH COOLER NORTHWESTERLY FLOW WILL PERSIST ACROSS THE AREA THROUGH
EARLY NEXT WEEK WHICH MAY PUT TEMPERATURES INTO THE BELOW NORMAL
CATEGORY. A FEW MINOR WAVES MAY MOVE THROUGH THIS FLOW PROVIDING
SMALL CHANCES FOR PCPN.
&&
.AVIATION...(00Z TAFS FOR KOFK...KLNK AND KOMA.)
ISSUED AT 620 PM CDT WED APR 15 2015
MVFR CIGS ARE LIKELY AT ALL SITES OVERNIGHT AND INTO THE DAY ON
THU...WITH THE LOWEST CIGS AT KOFK...POSSIBLY INTO THE IFR RANGE
FOR A PERIOD. WE WILL CONT TO LEAVE THE TAF SITES DRY THROUGH THE
PERIOD...ALTHOUGH A SPRINKLE OR LIGHT SHOWER WILL BE POSSIBLE
MAINLY ON THU MRNG AND ALSO JUST AFTER THIS TAF CYCLE. OTHERWISE
THE SOUTHEAST WINDS WILL CONTINUE TONIGHT AND THROUGH THE DAY ON
THU.
&&
.OAX WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
IA...NONE.
&&
$$
SHORT TERM...DEE
LONG TERM...KERN
AVIATION...BOUSTEAD
AREA FORECAST DISCUSSION
NWS LAS VEGAS NV
1026 AM PDT TUE APR 14 2015
.SYNOPSIS...A COLD FRONT WILL PRESS SOUTH ACROSS THE AREA THROUGH
THIS EVENING RESULTING IN GUSTY WINDS AND AREAS OF BLOWING DUST.
GUSTY NORTH WINDS WILL PERSIST DOWN THE COLORADO RIVER MUCH OF THE
WEEK. COOLER TEMPERATURES ARE EXPECTED FOR THE MIDDLE OF THE WEEK
FOLLOWED BY A REBOUND TO ABOVE NORMAL TEMPERATURES OVER THE WEEKEND.
&&
.UPDATE...GREETINGS FROM AWIPS II AT NWS LAS VEGAS AS WE ARE NOW
BACK UP AND RUNNING ON OUR NEW COMPUTER SYSTEM. PLEASE BARE WITH US
OVER THE NEXT FEW DAYS AS WE CONTINUE TO ADJUST TO OUR NEW SYSTEM WE
USE TO COMPOSE FORECASTS AND WARNINGS AS THERE STILL MAY BE A FEW
GLITCHES WE WORK OUT.
NOW SHIFTING FROM ROBOT TO METEOROLOGY MODE, A SURFACE COLD FRONT
WAS LOCATED FROM NEAR SANDBURG TO INDEPENDENCE TO TONOPAH TO WESTERN
WHITE PINE COUNTY. SURFACE OBSERVATIONS HAVE SHOWN A NICE WIND SHIFT
WITH THE FRONT TO THE NORTH EXCEPT IN THE OWENS VALLEY WHERE MORE OF
A WESTERLY SHIFT WAS NOTED AND THE FRONT`S LOCATION IS MORE ILL-
DEFINED. BLOWING DUST WAS REPORTED AT BOTH TONOPAH AND ELY AND THE
TIKABOO PEAK WEBCAM ALSO SHOWED THIS. BLOWING DUST WILL CONTINUE
BEHIND THE FRONT FOR SEVERAL HOURS WITH A SLOW IMPROVEMENT IN
VISIBILITY ESPECIALLY IN ANY AREAS WHERE THICKER AMOUNTS OF DUST GET
LOFTED.
THE LATEST HRRR MODEL BRINGS THE FRONT INTO THE LAS VEGAS VALLEY
LATE THIS AFTERNOON INTO EARLY THIS EVENING AROUND RUSH HOUR WHICH
WILL MAKE FOR A STRONG HEADWIND ESPECIALLY ON HIGHWAY 95 INTO THE
NORTHWEST PART OF THE VALLEY AS THE WIND SHIFT NORTHWEST. THE FRONT
WILL PRESS SOUTH EARLY THIS EVENING WITH GUSTY NORTH WINDS LINGERING
ACROSS THE AREA INTO WEDNESDAY WHICH SUPPORT THE WIND ADVISORIES
STILL IN EFFECT.
OVERALL, THE CURRENT FORECAST WAS ADJUSTED TO BRING UP SKY COVER
OVER NORTHEAST CLARK AND NORTHERN MOHAVE COUNTY FOR THE BAND OF
ENHANCED CIRRUS THAT HAS DEVELOPED AND WAS MOVING EAST. ELSEWHERE,
THINGS LOOK OK AND NO OTHER CHANGES WERE MADE TO THE GRIDS.
&&
.AVIATION...FOR MCCARRAN...SOUTHWEST WINDS WILL CONTINUE AHEAD OF A
COLD FRONT THROUGH THIS AFTERNOON WITH SUSTAINED WINDS OF 20-30 KTS
GUSTS OF 35-40 KTS. THE FRONT IS EXPECTED TO CROSS THE LAS VEGAS
VALLEY BETWEEN 23Z TODAY AND 03Z WEDNESDAY SHIFTING WINDS TO THE
NORTHWEST. WINDS WILL REMAIN NORTHWEST THROUGH TONIGHT AND GRADUALLY
DECREASE TO 15-25 KTS. STRONG WINDS ALOFT WILL CREATE THE POTENTIAL
FOR MECHANICAL TURBULENCE. FEW-SCT CLOUDS AOA 20K FEET AT TIMES.
FOR THE REST OF SOUTHERN NEVADA...NORTHWEST ARIZONA...AND SOUTHEAST
CALIFORNIA...A COLD FRONT WILL PRESS SOUTH ACROSS THE AREA THIS
AFTERNOON INTO THIS EVENING. WINDS WILL SHIFT FROM THE SOUTHWEST TO
THE NORTHWEST TO NORTH WITH THE FRONT WHICH SHOULD PASS THROUGH THE
LAS VEGAS VALLEY BETWEEN 23Z TODAY AND 03Z WEDNESDAY AND KEED
BETWEEN 03Z AND 05Z WEDNESDAY. GUSTS OF 30-40 KTS WITH LOCAL GUSTS
TO 50 KTS ARE EXPECTED JUST AHEAD OF AND BEHIND THE FRONT. BLDU IS
POSSIBLE ESPECIALLY DOWNWIND OF ANY DRY LAKE BEDS WITH VSBY REDUCED
TO MVFR OR LOWER. WINDS WILL GRADUALLY DECREASE OVERNIGHT TO 12-25
KTS. A FEW SHOWERS WILL BE POSSIBLE OVER CENTRAL NYE AND NORTHERN
LINCOLN COUNTIES THIS AFTERNOON INTO EARLY THIS EVENING WITH CIGS AS
LOW AS 6K-8K FEET NEAR ANY SHOWERS. &&
.FIRE WEATHER...DUE TO THE COMBINATION OF GUSTY WINDS AND LOW
RELATIVE HUMIDITY, RED FLAG WARNINGS ARE IN EFFECT FOR CALIFORNIA
ZONE 226 AND ARIZONA ZONE 102 AS FUELS OR ANTECEDENT CONDITIONS IN
THESE ZONES COULD CREATE THE POTENTIAL FOR RAPID WILDFIRE GROWTH.
ALTHOUGH ACROSS THE REMAINDER OF THE AREA GUSTY WINDS AND LOW
RELATIVE HUMIDITY WILL MEET CRITICAL CONDITIONS, FUELS ARE NOT YET
CONSIDERED READY SO NO HEADLINES ARE IN EFFECT.
&&
.PREVIOUS DISCUSSION...
ISSUED AT 305 AM PDT TUE APR 14 2015
ISSUED BY NATIONAL WEATHER SERVICE FLAGSTAFF AZ
.SHORT TERM...THROUGH WEDNESDAY AFTERNOON.
STRONG WINDS WILL PERSIST ALL NIGHT AND CONTINUE INTO WEDNESDAY FOR
LOCATIONS ALONG THE COLORADO RIVER.
.LONG TERM...THURSDAY THROUGH SUNDAY.
CLOSED UPPER LOW WILL CONTINUE TO SPIN OVER THE FOUR CORNERS
THURSDAY INTO FRIDAY WITH HIGH PRESSURE SLOWLY BUILDING IN FROM THE
WEST. THIS WILL LEAVE OUR REGION UNDER A PERSISTENT NORTHERLY FLOW
WITH GUSTY WINDS PERSISTING ESPECIALLY DOWN THE COLORADO RIVER. THE
WINDS WILL EASE A BIT OVER THE WEEKEND AS THE LOW DRIFTS EAST AND
HIGH PRESSURE TRIES TO BUILD BACK INTO THE AREA. THIS WILL RESULT IN
A WARMING TREND THROUGH THE WEEKEND WITH TEMPERATURES RETURNING TO
ABOVE NORMAL LEVELS.
MEANWHILE A WEAK LOW PRESSURE TROUGH MAY DEVELOP OVER NORTHERN
CALIFORNIA AND DRIFT SOUTHWARD WHICH COULD RESULT IN JUST ENOUGH
MOISTURE AND INSTABILITY TO SPARK OFF A FEW CUMULUS BUILD UPS AND
ISOLATED SHOWERS OR THUNDERSTORMS ACROSS THE SIERRA. I`VE ADDED A
SLIGHT CHANCE OF THUNDER TO THOSE AREAS SATURDAY THROUGH MONDAY.
OTHERWISE DRY CONDITIONS LOOK TO CONTINUE THROUGH EARLY NEXT WEEK.
&&
.SPOTTER INFORMATION STATEMENT...SPOTTERS SHOULD REPORT ANY REPORTS
OF STRONG WINDS EITHER WITH RESPECT TO GUSTS OR DAMAGE AS WELL AS
BLOWING DUST ALONG WITH ANY ESTIMATES OF VISIBILITY THROUGH
WEDNESDAY.
&&
$$
UPDATE/AVIATION/FIRE WEATHER...STACHELSKI
PREVIOUS...OUTLER
FOR MORE FORECAST INFORMATION...SEE US ON OUR WEBPAGE:
HTTP://WEATHER.GOV/LASVEGAS OR FOLLOW US ON FACEBOOK AND TWITTER
AREA FORECAST DISCUSSION
NWS LAS VEGAS NV
ISSUED BY NATIONAL WEATHER SERVICE FLAGSTAFF AZ
305 AM PDT TUE APR 14 2015
.SYNOPSIS...STRONG WINDS WILL CONTINUE TO SPREAD ACROSS THE ENTIRE
REGION TODAY AND WEDNESDAY. GUSTY NORTH WINDS WILL PERSIST DOWN
THE COLORADO RIVER MUCH OF THE WEEK. COOLER TEMPERATURES ARE
EXPECTED FOR THE MIDDLE OF THE WEEK FOLLOWED BY A REBOUND TO ABOVE
NORMAL TEMPERATURES OVER THE WEEKEND.
&&
.SHORT TERM...THROUGH WEDNESDAY AFTERNOON.
STRONG SHORTWAVE TROUGH WHICH WILL BE RESPONSIBLE FOR WIDESPREAD
WINDY CONDITIONS TODAY IS CURRENTLY MOVING ACROSS THE PACIFIC
NORTHWEST WITH ITS SOUTHERN EDGE DRAGGING ACROSS THE NORTHERN GREAT
BASIN BY LATER THIS MORNING. SO FAR WINDS ACROSS MOST OF OUR
OBSERVATION SITES IN THE SIERRA AND OWENS VALLEY HAVENT BEEN REAL
IMPRESSIVE BUT THE LATEST HRRR RUNS DO PICK UP THE WIND INTENSITY
CONSIDERABLY LATER THIS MORNING. STRONGEST WINDS LOOK TO ARRIVE
BETWEEN 9AM AND NOON AHEAD OF A STRONG COLD FRONT FOR THE SIERRA AND
OWENS VALLEY. AS THIS FRONT PASSES THROUGH LATER THIS MORNING WINDS
WILL SHIFT AROUND TO THE NORTHWEST AND REMAIN QUITE GUSTY FOR THE
REMAINDER OF THE AFTERNOON.
ELSEWHERE STRONG WINDS WILL OVERSPREAD MUCH OF NYE AND ESMERALDA
COUNTIES BEHIND THE COLD FRONT AND WILL BE QUITE STRONG. HIGH WIND
WARNINGS LOOK GOOD FOR THESE AREAS AND WE WILL NEED TO KEEP AN EYE
ON LINCOLN COUNTY AS WELL WHERE THE HRRR HAS PRETTY WIDESPREAD 25 TO
35 MPH SUSTAINED WINDS. AREAS OF BLOWING DUST WILL BE LIKELY WITH
ALL THIS WIND AS WELL. THIS FRONT WILL CONTINUE TO PROGRESS SOUTH
THROUGH THE AFTERNOON...REACHING THE LAS VEGAS VALLEY BY AROUND 5PM
AND OUR SOUTHERN ZONES BY 11PM. VERY STRONG WINDS CAN BE EXPECTED
IMMEDIATELY BEHIND THE FRONT BEFORE SLOWLY WEAKENING OVERNIGHT BUT
REMAINING GUSTY. STRONG WINDS WILL PERSIST ALL NIGHT AND CONTINUE
INTO WEDNESDAY FOR LOCATIONS ALONG THE COLORADO RIVER.
CURRENT WARNING AND ADVISORY PRODUCTS LOOK GOOD AND HAVE NOT MADE
ANY FURTHER ADJUSTMENTS TO THEM.
.LONG TERM...THURSDAY THROUGH SUNDAY.
CLOSED UPPER LOW WILL CONTINUE TO SPIN OVER THE FOUR CORNERS
THURSDAY INTO FRIDAY WITH HIGH PRESSURE SLOWLY BUILDING IN FROM THE
WEST. THIS WILL LEAVE OUR REGION UNDER A PERSISTENT NORTHERLY FLOW
WITH GUSTY WINDS PERSISTING ESPECIALLY DOWN THE COLORADO RIVER. THE
WINDS WILL EASE A BIT OVER THE WEEKEND AS THE LOW DRIFTS EAST AND
HIGH PRESSURE TRIES TO BUILD BACK INTO THE AREA. THIS WILL RESULT IN
A WARMING TREND THROUGH THE WEEKEND WITH TEMPERATURES RETURNING TO
ABOVE NORMAL LEVELS.
MEANWHILE A WEAK LOW PRESSURE TROUGH MAY DEVELOP OVER NORTHERN
CALIFORNIA AND DRIFT SOUTHWARD WHICH COULD RESULT IN JUST ENOUGH
MOISTURE AND INSTABILITY TO SPARK OFF A FEW CUMULUS BUILD UPS AND
ISOLATED SHOWERS OR THUNDERSTORMS ACROSS THE SIERRA. IVE ADDED A
SLIGHT CHANCE OF THUNDER TO THOSE AREAS SATURDAY THROUGH MONDAY.
OTHERWISE DRY CONDITIONS LOOK TO CONTINUE THROUGH EARLY NEXT WEEK.
&&
.AVIATION...FOR MCCARRAN...SOUTHWEST WINDS ARE EXPECTED TO INCREASE
DURING THE MORNING HOURS AS A COLD FRONT APPROACHES THE AREA. WINDS
WILL GENERALLY BE 10 TO 15 KTS WITH OCCASIONAL GUSTS TO AROUND 25
KTS AND THEN INCREASE TO AROUND 15 TO 20 KNOTS WITH GUSTS
APPROACHING 30 TO 35 KTS AFTER 18Z. AREAS OF BLOWING DUST ARE
POSSIBLE AROUND THE AIRPORT WITH VISIBILITY DROPPING AS LOW AS 5SM
AT TIMES. A COLD FRONT IS EXPECTED TO PUSH THROUGH THE VEGAS VALLEY
AROUND 00Z THIS EVENING WITH WINDS SHIFTING TO THE NORTHWEST. WIND
SPEEDS ARE STILL EXPECTED TO REMAIN IN THE 15-20 KT RANGE WITH GUSTS
UP TO 30KTS. WINDS WILL GRADUALLY DECREASE DURING THE OVERNIGHT
HORUS. MINIMAL CLOUD COVER IS EXPECTED.
FOR THE REST OF SOUTHERN NEVADA...NORTHWEST ARIZONA...AND SOUTHEAST
CALIFORNIA...SOUTHWEST WINDS ARE EXPECTED TO INCREASE ACROSS THE
REGION AHEAD OF A COLD FRONT THAT WILL MOVE THROUGH THE REGION
TODAY. WINDS AHEAD OF THE COLD FRONT ARE EXPECTED TO BE IN THE 15-20
KT RANGE WITH GUSTS BETWEEN 30-35 KTS. SOME LOCATIONS MAY SEE GUSTS
EXCEEDING 40KTS. THIS WILL CAUSE AREAS OF BLOWING DUST WHICH COULD
REDUCE VISIBILITY DOWN TO 3-5SM...MAINLY BETWEEN 17-23Z. THIS FRONT
IS FORECAST TO MOVE THROUGH NORTHERN INYO AND ESMERALDA COUNTIES
AROUND 18Z AND THEN PROGRESS SOUTH DURING THE AFTERNOON. THE FRONT
IS EXPECTED TO REACH SOUTHERN NEVADA AROUND 00Z AND CONTINUE TO MOVE
SOUTH EARLY THIS EVENING. WINDS BEHIND THE FRONT WILL TURN NORTHWEST
WITH WIND SPEEDS AROUND 15-20 KTS AND GUSTS BETWEEN 30-35 KTS WHILE
GRADUALLY DECREASING OVERNIGHT. A FEW SHOWERS WILL BE POSSIBLE OVER
CENTRAL NYE AND NORTHERN LINCOLN COUNTIES THIS AFTERNOON...OTHERWISE
MINIMAL CLOUD COVER IS EXPECTED.
&&
.SPOTTER INFORMATION STATEMENT...SPOTTER ACTIVATION IS NOT EXPECTED
TODAY. ANY SIGNIFICANT WEATHER SHOULD BE REPORTED ACCORDING TO
STANDARD OPERATING PROCEDURES.
&&
$$
OUTLER
FOR MORE FORECAST INFORMATION...SEE US ON OUR WEBPAGE:
HTTP://WEATHER.GOV/LASVEGAS OR FOLLOW US ON FACEBOOK AND TWITTER
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
141 PM EDT TUE APR 14 2015
.SYNOPSIS...
HIGH PRESSURE WILL PUSH DOWN FROM CANADA WITH FAIR WEATHER AND
SEASONAL TEMPERATURES FOR THIS AFTERNOON THROUGH THURSDAY. THE
NEXT CHANCE FOR RAIN SHOWERS WILL COME ON THURSDAY NIGHT AS A WARM
FRONT APPROACHES THE REGION.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
UPDATED AT 11 AM... HIGH CLOUDS ARE STREAMING NORTHEAST ACROSS PA
AND SOUTHERN NY LATE THIS MORNING NORTH OF A STALLED FRONTAL
BOUNDARY OVER THE MID-ATLANTIC. THESE CLOUDS WILL PERSIST ACROSS
MUCH OF THE AREA SOUTH OF THE THRUWAY TODAY AND WILL ACT TO KEEP
TEMPERATURES DOWN SLIGHTLY OVER THE PREVIOUS FORECAST. HAVE
LOWERED MAX TEMPS BY A FEW DEGREES ESPECIALLY IN PA WHERE CLOUDS
WILL BE THICKEST. HIGHS SHOULD STILL REACH NEAR TO JUST ABOVE 60
IN MOST OF NORTHEAST PA AND SOUTHERN NY... WITH MID 60S IN SUNNIER
AREAS UP NEAR THE THRUWAY. PREVIOUS DISCUSSION IS BELOW.
RADARS SHOW A BAND OF SHOWERS OF RAIN FROM ABOUT UTICA TO
BINGHAMTON AND TOWANDA AT THIS TIME AND WORKING EAST AS THE UPPER
LEVEL WAVE MOVES INTO THE EASTERN GREAT LAKES. THIS WAVE HAS
PROVIDED THE IMPETUS TO PUSH A COLD FRONT INTO NY AND PA. HI RES
MODELS CONTINUE TO INDICATE THAT THIS BAND OF SHRA WILL CONTINUE
EASTWARD AND CLEAR THE POCONOS TO WRN CATSKILLS BY AROUND 12Z AS
THE UPPER WAVE AND COLD FRONT MOVE THRU. THERE WAS NO LIGHTNING
DETECTED AND SHOWALTER INDICES WERE ABOVE 0C SO NO THUNDER
IN GRIDS. THE HRRR IS QUICKEST IN MOVING PRECIP THRU NE PA/SERN NY
WITH THE HI RES ARW AND NMM HOLDING THE PRECIP BACK A COUPLE
HOURS LONGER. THE RAP REFLECTIVITY FIELDS SHOW THAT THE PRECIP
CLEARS THESE AREAS BY 12-13Z. SO I HAVE HELD ON TO SLGHT CHC AT
12Z IN THESE AREAS. REST OF FORECAST AREA WILL BE FREE OF PRECIP
BTWN 6Z AND 12Z.
AFTER THE PRECIP PASSES BY CLOUDS WILL CLEAR FOR A TIME THIS
MORNING. BUT COLD ADVECTION AT 850 MB AND SFC DEWPOINTS STILL IN
UPPER 30S SHUD LEAD TO SCT STRATOCUMULUS FORMING FOR A TIME BEFORE
ENUF DIURNAL MIXING TAKES PLACE BY MIDDAY TO MIX OUT THESE
CLOUDS. MODEL SOUNDINGS SUGGEST THIS AS WELL. THEN BY AFTERNOON
CIRRUS IN ADVANCE OF THE UPPER LEVEL LOW OVER TEXAS WILL ADVECT
NORTHEAST INTO THE UPPER CONFLUENT ZONE ALOFT WHICH CUTS ACRS
CENTRAL NY BY 18Z-21Z. SO WE EXPECT A SHIELD OF CIRRUS FROM SRN
NY ACROSS PA THIS AFTERNOON WHICH WILL BE THICK ENUF TO SPOIL A
MOSTLY SUNNY FORECAST. THESE CLOUDS WILL PUSH SOUTHEAST OF NE
PA/SERN NY THIS EVENING AS ANOTHER NRN BRANCH UPPER LEVEL SHORT
WAVE PUSHES SOUTHEAST FROM ONTARIO. SO... WE HAVE VARYING AMNTS
OF CLOUD COVER IN THE GRIDS FOR TODAY. NO POPS WARRANTING PRECIP
EXCEPT 12Z-14Z IN OUR FAR SE AND THESE ARE IN THE SLGHT CHC CAT.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH THURSDAY NIGHT/...
AFTER CIRRUS SHIELD PUSHES SOUTHEAST OF NE PA AND SERN NY THIS
EVENING AN UPPER LEVEL WAVE WILL PUSH SOUTHEAST INTO NRN NEW
ENGLAND LATER TONIGHT AND WEDNESDAY WITH NY AND PA BEING ON THE
SUBSDC SIDE OF THIS TROUGH WITH THE UPPER RDG AXIS OVER THE ERN
LAKES. THIS WILL SUPPORT HIGH PRESSURE TO BUILD SOUTHWARD FROM
CANADA WITH A DRIER AIR AND SEASONAL TEMPS FOR TONIGHT...WED AND
WED NGT.
BY THURSDAY THE SFC HIGH SHIFTS OFF THE NEW ENGLAND COAST AND A
SRLY FLOW OF AIR WILL DEVELOP OVER NY AND PA WITH MID TO HI CLOUDS
SPREADING FROM SW TO NE ACRS C NY AND NE PA. LOOKING AT THE
SYNOPTIC MODELS IT LOOKS LIKE ANY PRECIP WILL HOLD OFF UNTIL AFTER
00Z FRI SO THU LOOKS DRY AND MILDER WITH SRLY WINDS.
FOR THURSDAY NIGHT...THE GFS...EURO...CMC AND UKMET ALL SHOW
DECENT LOW-LEVEL THETA-E ADVECTION ARND 850 MB WHICH WILL ALLOW
FOR DESTABLIZATION AND SHRA ACVTY TO WORK INTO NY AND NRN PA FROM
W TO E OVRNGT. IT LOOKS LIKE WRN AND CNTRL NY GET INTO SOME SHRA
ACVTY BTWN 00Z AND 06Z AND NE PA AND SERN NY AFTER 6Z SO HAVE
WORKED POP TIMING TO REFLECT THIS. SHOWALTER INDICES SUGGEST THE
AMS WILL BE STABLE ENUF SO NO MENTION OF THUNDER AT THIS POINT.
QPF AMNTS APPEARS TO BE ON THE ORDER OF ABT .25 INCHES WHICH WILL
NOT CAUSE ANY HYDRO ISSUES. THE NAM IS THE ODD MODEL OUT WITH MUCH
DRIER LL AIR TO START AND NOT ENUF MOISTURE ADVTN TO LEAD TO MUCH
PRECIP. SO WENT WITH GFS/EURO/CMC AND UKMET IDEAS AND HAVE CHC
POPS SHRA THU NGT.
&&
.LONG TERM /FRIDAY THROUGH MONDAY/...
LONGWAVE RIDGING IS FORECAST TO BUILD ACROSS THE EASTERN U.S.
EARLY IN THE LONG TERM PERIOD BEFORE THE PATTERN BECOMES A BIT
TRICKIER LATE IN THE PERIOD AS MODEL SOLUTIONS DIVERGE
SIGNIFICANTLY INTO NEXT WEEKEND.
QUIET WEATHER EXPECTED THUR INTO FRIDAY WITH NEAR TO SLIGHTLY ABOVE
NORMAL TEMPS. THE CHANCE OF SHOWERS INCREASES SAT INTO MONDAY AS
SHORTWAVE ENERGY ROUND THE UPPER RIDGE NEXT WEEKEND. THE EXTENT OF
LOWER HEIGHTS...WHICH WOULD SUPPORT A WETTER SOLUTION...IS IN
QUESTION...WITH THE GFS SYSTEM KEEPING A STRONGER RIDGE. THE ECMWF
BRINGS AN UPPER LOW EASTWARD OUT OF THE PLAINS INTO THE REGION.
&&
.AVIATION /18Z TUESDAY THROUGH SUNDAY/...
VFR CONDITIONS WILL PREVAIL THROUGH THURSDAY... WITH THE POSSIBLE
EXCEPTION OF SPOTTY LIGHT FOG IN THE RIVER VALLEYS WEDNESDAY
MORNING. WINDS WILL BE LIGHT AND VARIABLE TONIGHT... THEN
NORTHWEST AT 5 TO 15 KTS WEDNESDAY... BECOMING LIGHT AND VARIABLE
AGAIN WEDNESDAY NIGHT INTO THURSDAY.
.OUTLOOK...
WED/THUR...VFR.
THU NGT-SAT...POSSIBLE RESTRICTIONS IN -SHRA.
&&
.FIRE WEATHER...
DRIER AIR BEHIND A COLD FRONTAL PASSAGE WILL LEAD TO RELATIVE
HUMIDITIES FALLING BELOW 30 PERCENT THIS AFTERNOON. WINDS LOOK TO
BE LESS THAN 20 MPH ACROSS CENTRAL NEW YORK AND NORTHEAST
PENNSYLVANIA. IN ADDITION THE RAIN SHOWERS FROM LAST NIGHT AND
EARLY THIS MORNING SHOULD KEEP FINE FUELS ABOVE 10 PERCENT MOST OF
THE DAY. THEREFORE FIRE CONDITIONS ARE NOT EXPECTED TO APPROACH RED
FLAG CONDITIONS TODAY.
&&
.BGM WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NY...NONE.
&&
$$
SYNOPSIS...MSE
NEAR TERM...DJN/MSE
SHORT TERM...DJN
LONG TERM...
AVIATION...DGM/MSE
FIRE WEATHER...
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
138 PM EDT TUE APR 14 2015
.SYNOPSIS...
A COLD FRONT WILL EXIT NORTHEAST PENNSYLVANIA AND SOUTHEAST NEW
YORK EARLY THIS MORNING TAKING THE SHOWERS WITH IT. AFTER THIS
FRONT PASSES BY, HIGH PRESSURE WILL PUSH DOWN FROM CANADA WITH
FAIR WEATHER AND SEASONAL TEMPERATURES FOR THE REST OF TODAY
THROUGH THURSDAY. THE NEXT CHANCE FOR RAIN SHOWERS WILL COME ON
THURSDAY NIGHT AS A WARM FRONT APPROACHES THE REGION.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
UPDATED AT 11 AM... HIGH CLOUDS ARE STREAMING NORTHEAST ACROSS PA
AND SOUTHERN NY LATE THIS MORNING NORTH OF A STALLED FRONTAL
BOUNDARY OVER THE MID-ATLANTIC. THESE CLOUDS WILL PERSIST ACROSS
MUCH OF THE AREA SOUTH OF THE THRUWAY TODAY AND WILL ACT TO KEEP
TEMPERATURES DOWN SLIGHTLY OVER THE PREVIOUS FORECAST. HAVE
LOWERED MAX TEMPS BY A FEW DEGREES ESPECIALLY IN PA WHERE CLOUDS
WILL BE THICKEST. HIGHS SHOULD STILL REACH NEAR TO JUST ABOVE 60
IN MOST OF NORTHEAST PA AND SOUTHERN NY... WITH MID 60S IN SUNNIER
AREAS UP NEAR THE THRUWAY. PREVIOUS DISCUSSION IS BELOW.
RADARS SHOW A BAND OF SHOWERS OF RAIN FROM ABOUT UTICA TO
BINGHAMTON AND TOWANDA AT THIS TIME AND WORKING EAST AS THE UPPER
LEVEL WAVE MOVES INTO THE EASTERN GREAT LAKES. THIS WAVE HAS
PROVIDED THE IMPETUS TO PUSH A COLD FRONT INTO NY AND PA. HI RES
MODELS CONTINUE TO INDICATE THAT THIS BAND OF SHRA WILL CONTINUE
EASTWARD AND CLEAR THE POCONOS TO WRN CATSKILLS BY AROUND 12Z AS
THE UPPER WAVE AND COLD FRONT MOVE THRU. THERE WAS NO LIGHTNING
DETECTED AND SHOWALTER INDICES WERE ABOVE 0C SO NO THUNDER
IN GRIDS. THE HRRR IS QUICKEST IN MOVING PRECIP THRU NE PA/SERN NY
WITH THE HI RES ARW AND NMM HOLDING THE PRECIP BACK A COUPLE
HOURS LONGER. THE RAP REFLECTIVITY FIELDS SHOW THAT THE PRECIP
CLEARS THESE AREAS BY 12-13Z. SO I HAVE HELD ON TO SLGHT CHC AT
12Z IN THESE AREAS. REST OF FORECAST AREA WILL BE FREE OF PRECIP
BTWN 6Z AND 12Z.
AFTER THE PRECIP PASSES BY CLOUDS WILL CLEAR FOR A TIME THIS
MORNING. BUT COLD ADVECTION AT 850 MB AND SFC DEWPOINTS STILL IN
UPPER 30S SHUD LEAD TO SCT STRATOCUMULUS FORMING FOR A TIME BEFORE
ENUF DIURNAL MIXING TAKES PLACE BY MIDDAY TO MIX OUT THESE
CLOUDS. MODEL SOUNDINGS SUGGEST THIS AS WELL. THEN BY AFTERNOON
CIRRUS IN ADVANCE OF THE UPPER LEVEL LOW OVER TEXAS WILL ADVECT
NORTHEAST INTO THE UPPER CONFLUENT ZONE ALOFT WHICH CUTS ACRS
CENTRAL NY BY 18Z-21Z. SO WE EXPECT A SHIELD OF CIRRUS FROM SRN
NY ACROSS PA THIS AFTERNOON WHICH WILL BE THICK ENUF TO SPOIL A
MOSTLY SUNNY FORECAST. THESE CLOUDS WILL PUSH SOUTHEAST OF NE
PA/SERN NY THIS EVENING AS ANOTHER NRN BRANCH UPPER LEVEL SHORT
WAVE PUSHES SOUTHEAST FROM ONTARIO. SO... WE HAVE VARYING AMNTS
OF CLOUD COVER IN THE GRIDS FOR TODAY. NO POPS WARRANTING PRECIP
EXCEPT 12Z-14Z IN OUR FAR SE AND THESE ARE IN THE SLGHT CHC CAT.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH THURSDAY NIGHT/...
AFTER CIRRUS SHIELD PUSHES SOUTHEAST OF NE PA AND SERN NY THIS
EVENING AN UPPER LEVEL WAVE WILL PUSH SOUTHEAST INTO NRN NEW
ENGLAND LATER TONIGHT AND WEDNESDAY WITH NY AND PA BEING ON THE
SUBSDC SIDE OF THIS TROUGH WITH THE UPPER RDG AXIS OVER THE ERN
LAKES. THIS WILL SUPPORT HIGH PRESSURE TO BUILD SOUTHWARD FROM
CANADA WITH A DRIER AIR AND SEASONAL TEMPS FOR TONIGHT...WED AND
WED NGT.
BY THURSDAY THE SFC HIGH SHIFTS OFF THE NEW ENGLAND COAST AND A
SRLY FLOW OF AIR WILL DEVELOP OVER NY AND PA WITH MID TO HI CLOUDS
SPREADING FROM SW TO NE ACRS C NY AND NE PA. LOOKING AT THE
SYNOPTIC MODELS IT LOOKS LIKE ANY PRECIP WILL HOLD OFF UNTIL AFTER
00Z FRI SO THU LOOKS DRY AND MILDER WITH SRLY WINDS.
FOR THURSDAY NIGHT...THE GFS...EURO...CMC AND UKMET ALL SHOW
DECENT LOW-LEVEL THETA-E ADVECTION ARND 850 MB WHICH WILL ALLOW
FOR DESTABLIZATION AND SHRA ACVTY TO WORK INTO NY AND NRN PA FROM
W TO E OVRNGT. IT LOOKS LIKE WRN AND CNTRL NY GET INTO SOME SHRA
ACVTY BTWN 00Z AND 06Z AND NE PA AND SERN NY AFTER 6Z SO HAVE
WORKED POP TIMING TO REFLECT THIS. SHOWALTER INDICES SUGGEST THE
AMS WILL BE STABLE ENUF SO NO MENTION OF THUNDER AT THIS POINT.
QPF AMNTS APPEARS TO BE ON THE ORDER OF ABT .25 INCHES WHICH WILL
NOT CAUSE ANY HYDRO ISSUES. THE NAM IS THE ODD MODEL OUT WITH MUCH
DRIER LL AIR TO START AND NOT ENUF MOISTURE ADVTN TO LEAD TO MUCH
PRECIP. SO WENT WITH GFS/EURO/CMC AND UKMET IDEAS AND HAVE CHC
POPS SHRA THU NGT.
&&
.LONG TERM /FRIDAY THROUGH MONDAY/...
LONGWAVE RIDGING IS FORECAST TO BUILD ACROSS THE EASTERN U.S.
EARLY IN THE LONG TERM PERIOD BEFORE THE PATTERN BECOMES A BIT
TRICKIER LATE IN THE PERIOD AS MODEL SOLUTIONS DIVERGE
SIGNIFICANTLY INTO NEXT WEEKEND.
QUIET WEATHER EXPECTED THUR INTO FRIDAY WITH NEAR TO SLIGHTLY ABOVE
NORMAL TEMPS. THE CHANCE OF SHOWERS INCREASES SAT INTO MONDAY AS
SHORTWAVE ENERGY ROUND THE UPPER RIDGE NEXT WEEKEND. THE EXTENT OF
LOWER HEIGHTS...WHICH WOULD SUPPORT A WETTER SOLUTION...IS IN
QUESTION...WITH THE GFS SYSTEM KEEPING A STRONGER RIDGE. THE ECMWF
BRINGS AN UPPER LOW EASTWARD OUT OF THE PLAINS INTO THE REGION.
&&
.AVIATION /18Z TUESDAY THROUGH SUNDAY/...
VFR CONDITIONS WILL PREVAIL THROUGH THURSDAY... WITH THE POSSIBLE
EXCEPTION OF SPOTTY LIGHT FOG IN THE RIVER VALLEYS WEDNESDAY
MORNING. WINDS WILL BE LIGHT AND VARIABLE TONIGHT... THEN
NORTHWEST AT 5 TO 15 KTS WEDNESDAY... BECOMING LIGHT AND VARIABLE
AGAIN WEDNESDAY NIGHT INTO THURSDAY.
.OUTLOOK...
WED/THUR...VFR.
THU NGT-SAT...POSSIBLE RESTRICTIONS IN -SHRA.
&&
.FIRE WEATHER...
DRIER AIR BEHIND A COLD FRONTAL PASSAGE WILL LEAD TO RELATIVE
HUMIDITIES FALLING BELOW 30 PERCENT THIS AFTERNOON. WINDS LOOK TO
BE LESS THAN 20 MPH ACROSS CENTRAL NEW YORK AND NORTHEAST
PENNSYLVANIA. IN ADDITION THE RAIN SHOWERS FROM LAST NIGHT AND
EARLY THIS MORNING SHOULD KEEP FINE FUELS ABOVE 10 PERCENT MOST OF
THE DAY. THEREFORE FIRE CONDITIONS ARE NOT EXPECTED TO APPROACH RED
FLAG CONDITIONS TODAY.
&&
.BGM WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NY...NONE.
&&
$$
SYNOPSIS...DJN
NEAR TERM...DJN/MSE
SHORT TERM...DJN
LONG TERM...
AVIATION...DGM/MSE
FIRE WEATHER...
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
1106 AM EDT TUE APR 14 2015
.SYNOPSIS...
A COLD FRONT WILL EXIT NORTHEAST PENNSYLVANIA AND SOUTHEAST NEW
YORK EARLY THIS MORNING TAKING THE SHOWERS WITH IT. AFTER THIS
FRONT PASSES BY, HIGH PRESSURE WILL PUSH DOWN FROM CANADA WITH
FAIR WEATHER AND SEASONAL TEMPERATURES FOR THE REST OF TODAY
THROUGH THURSDAY. THE NEXT CHANCE FOR RAIN SHOWERS WILL COME ON
THURSDAY NIGHT AS A WARM FRONT APPROACHES THE REGION.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
UPDATED AT 11 AM... HIGH CLOUDS ARE STREAMING NORTHEAST ACROSS PA
AND SOUTHERN NY LATE THIS MORNING NORTH OF A STALLED FRONTAL
BOUNDARY OVER THE MID-ATLANTIC. THESE CLOUDS WILL PERSIST ACROSS
MUCH OF THE AREA SOUTH OF THE THRUWAY TODAY AND WILL ACT TO KEEP
TEMPERATURES DOWN SLIGHTLY OVER THE PREVIOUS FORECAST. HAVE
LOWERED MAX TEMPS BY A FEW DEGREES ESPECIALLY IN PA WHERE CLOUDS
WILL BE THICKEST. HIGHS SHOULD STILL REACH NEAR TO JUST ABOVE 60
IN MOST OF NORTHEAST PA AND SOUTHERN NY... WITH MID 60S IN SUNNIER
AREAS UP NEAR THE THRUWAY. PREVIOUS DISCUSSION IS BELOW.
RADARS SHOW A BAND OF SHOWERS OF RAIN FROM ABOUT UTICA TO
BINGHAMTON AND TOWANDA AT THIS TIME AND WORKING EAST AS THE UPPER
LEVEL WAVE MOVES INTO THE EASTERN GREAT LAKES. THIS WAVE HAS
PROVIDED THE IMPETUS TO PUSH A COLD FRONT INTO NY AND PA. HI RES
MODELS CONTINUE TO INDICATE THAT THIS BAND OF SHRA WILL CONTINUE
EASTWARD AND CLEAR THE POCONOS TO WRN CATSKILLS BY AROUND 12Z AS
THE UPPER WAVE AND COLD FRONT MOVE THRU. THERE WAS NO LIGHTNING
DETECTED AND SHOWALTER INDICES WERE ABOVE 0C SO NO THUNDER
IN GRIDS. THE HRRR IS QUICKEST IN MOVING PRECIP THRU NE PA/SERN NY
WITH THE HI RES ARW AND NMM HOLDING THE PRECIP BACK A COUPLE
HOURS LONGER. THE RAP REFLECTIVITY FIELDS SHOW THAT THE PRECIP
CLEARS THESE AREAS BY 12-13Z. SO I HAVE HELD ON TO SLGHT CHC AT
12Z IN THESE AREAS. REST OF FORECAST AREA WILL BE FREE OF PRECIP
BTWN 6Z AND 12Z.
AFTER THE PRECIP PASSES BY CLOUDS WILL CLEAR FOR A TIME THIS
MORNING. BUT COLD ADVECTION AT 850 MB AND SFC DEWPOINTS STILL IN
UPPER 30S SHUD LEAD TO SCT STRATOCUMULUS FORMING FOR A TIME BEFORE
ENUF DIURNAL MIXING TAKES PLACE BY MIDDAY TO MIX OUT THESE
CLOUDS. MODEL SOUNDINGS SUGGEST THIS AS WELL. THEN BY AFTERNOON
CIRRUS IN ADVANCE OF THE UPPER LEVEL LOW OVER TEXAS WILL ADVECT
NORTHEAST INTO THE UPPER CONFLUENT ZONE ALOFT WHICH CUTS ACRS
CENTRAL NY BY 18Z-21Z. SO WE EXPECT A SHIELD OF CIRRUS FROM SRN
NY ACROSS PA THIS AFTERNOON WHICH WILL BE THICK ENUF TO SPOIL A
MOSTLY SUNNY FORECAST. THESE CLOUDS WILL PUSH SOUTHEAST OF NE
PA/SERN NY THIS EVENING AS ANOTHER NRN BRANCH UPPER LEVEL SHORT
WAVE PUSHES SOUTHEAST FROM ONTARIO. SO... WE HAVE VARYING AMNTS
OF CLOUD COVER IN THE GRIDS FOR TODAY. NO POPS WARRANTING PRECIP
EXCEPT 12Z-14Z IN OUR FAR SE AND THESE ARE IN THE SLGHT CHC CAT.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH THURSDAY NIGHT/...
AFTER CIRRUS SHIELD PUSHES SOUTHEAST OF NE PA AND SERN NY THIS
EVENING AN UPPER LEVEL WAVE WILL PUSH SOUTHEAST INTO NRN NEW
ENGLAND LATER TONIGHT AND WEDNESDAY WITH NY AND PA BEING ON THE
SUBSDC SIDE OF THIS TROUGH WITH THE UPPER RDG AXIS OVER THE ERN
LAKES. THIS WILL SUPPORT HIGH PRESSURE TO BUILD SOUTHWARD FROM
CANADA WITH A DRIER AIR AND SEASONAL TEMPS FOR TONIGHT...WED AND
WED NGT.
BY THURSDAY THE SFC HIGH SHIFTS OFF THE NEW ENGLAND COAST AND A
SRLY FLOW OF AIR WILL DEVELOP OVER NY AND PA WITH MID TO HI CLOUDS
SPREADING FROM SW TO NE ACRS C NY AND NE PA. LOOKING AT THE
SYNOPTIC MODELS IT LOOKS LIKE ANY PRECIP WILL HOLD OFF UNTIL AFTER
00Z FRI SO THU LOOKS DRY AND MILDER WITH SRLY WINDS.
FOR THURSDAY NIGHT...THE GFS...EURO...CMC AND UKMET ALL SHOW
DECENT LOW-LEVEL THETA-E ADVECTION ARND 850 MB WHICH WILL ALLOW
FOR DESTABLIZATION AND SHRA ACVTY TO WORK INTO NY AND NRN PA FROM
W TO E OVRNGT. IT LOOKS LIKE WRN AND CNTRL NY GET INTO SOME SHRA
ACVTY BTWN 00Z AND 06Z AND NE PA AND SERN NY AFTER 6Z SO HAVE
WORKED POP TIMING TO REFLECT THIS. SHOWALTER INDICES SUGGEST THE
AMS WILL BE STABLE ENUF SO NO MENTION OF THUNDER AT THIS POINT.
QPF AMNTS APPEARS TO BE ON THE ORDER OF ABT .25 INCHES WHICH WILL
NOT CAUSE ANY HYDRO ISSUES. THE NAM IS THE ODD MODEL OUT WITH MUCH
DRIER LL AIR TO START AND NOT ENUF MOISTURE ADVTN TO LEAD TO MUCH
PRECIP. SO WENT WITH GFS/EURO/CMC AND UKMET IDEAS AND HAVE CHC
POPS SHRA THU NGT.
&&
.LONG TERM /FRIDAY THROUGH MONDAY/...
LONGWAVE RIDGING IS FORECAST TO BUILD ACROSS THE EASTERN U.S.
EARLY IN THE LONG TERM PERIOD BEFORE THE PATTERN BECOMES A BIT
TRICKIER LATE IN THE PERIOD AS MODEL SOLUTIONS DIVERGE
SIGNIFICANTLY INTO NEXT WEEKEND.
QUIET WEATHER EXPECTED THUR INTO FRIDAY WITH NEAR TO SLIGHTLY ABOVE
NORMAL TEMPS. THE CHANCE OF SHOWERS INCREASES SAT INTO MONDAY AS
SHORTWAVE ENERGY ROUND THE UPPER RIDGE NEXT WEEKEND. THE EXTENT OF
LOWER HEIGHTS...WHICH WOULD SUPPORT A WETTER SOLUTION...IS IN
QUESTION...WITH THE GFS SYSTEM KEEPING A STRONGER RIDGE. THE ECMWF
BRINGS AN UPPER LOW EASTWARD OUT OF THE PLAINS INTO THE REGION.
&&
.AVIATION /15Z TUESDAY THROUGH SATURDAY/...
MUCH DRIER LL AIR BHD THE COLD FNT AND ASSOCIATED PCPN THIS MRNG
RESULTING IN VFR CONDS ALL STATIONS. XCPTN IS SOME GND FOG AT ELM
BRINGING IFR VSBYS...WHICH SHD LIFT OFF QUICKLY. XPCT VFR CONDS
THRU THE TAF PD AS A SFC HIPRES BLDS INTO THE REGION. WV MVG THRU
THE OH VLY WILL KEEP HI CLDS OVER THE AREA HWVR.
.OUTLOOK...
WED/THUR...VFR.
THU NGT-SAT...POSSIBLE RESTRICTIONS IN -SHRA.
&&
.FIRE WEATHER...
DRIER AIR BEHIND A COLD FRONTAL PASSAGE WILL LEAD TO RELATIVE
HUMIDITIES FALLING BELOW 30 PERCENT THIS AFTERNOON. WINDS LOOK TO
BE LESS THAN 20 MPH ACROSS CENTRAL NEW YORK AND NORTHEAST
PENNSYLVANIA. IN ADDITION THE RAIN SHOWERS FROM LAST NIGHT AND
EARLY THIS MORNING SHOULD KEEP FINE FUELS ABOVE 10 PERCENT MOST OF
THE DAY. THEREFORE FIRE CONDITIONS ARE NOT EXPECTED TO APPROACH RED
FLAG CONDITIONS TODAY.
&&
.BGM WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NY...NONE.
&&
$$
SYNOPSIS...DJN
NEAR TERM...DJN/MSE
SHORT TERM...DJN
LONG TERM...
AVIATION...DGM
FIRE WEATHER...
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
630 AM EDT TUE APR 14 2015
.SYNOPSIS...
A COLD FRONT WILL EXIT NORTHEAST PENNSYLVANIA AND SOUTHEAST NEW
YORK EARLY THIS MORNING TAKING THE SHOWERS WITH IT. AFTER THIS
FRONT PASSES BY, HIGH PRESSURE WILL PUSH DOWN FROM CANADA WITH
FAIR WEATHER AND SEASONAL TEMPERATURES FOR THE REST OF TODAY
THROUGH THURSDAY. THE NEXT CHANCE FOR RAIN SHOWERS WILL COME ON
THURSDAY NIGHT AS A WARM FRONT APPROACHES THE REGION.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
RADARS SHOW A BAND OF SHOWERS OF RAIN FROM ABOUT UTICA TO
BINGHAMTON AND TOWANDA AT THIS TIME AND WORKING EAST AS THE UPPER
LEVEL WAVE MOVES INTO THE EASTERN GREAT LAKES. THIS WAVE HAS
PROVIDED THE IMPETUS TO PUSH A COLD FRONT INTO NY AND PA. HI RES
MODELS CONTINUE TO INDICATE THAT THIS BAND OF SHRA WILL CONTINUE
EASTWARD AND CLEAR THE POCONOS TO WRN CATSKILLS BY AROUND 12Z AS
THE UPPER WAVE AND COLD FRONT MOVE THRU. THERE WAS NO LIGHTNING
DETECTED AND SHOWALTER INDICES WERE ABOVE 0C SO NO THUNDER
IN GRIDS. THE HRRR IS QUICKEST IN MOVING PRECIP THRU NE PA/SERN NY
WITH THE HI RES ARW AND NMM HOLDING THE PRECIP BACK A COUPLE
HOURS LONGER. THE RAP REFLECTIVITY FIELDS SHOW THAT THE PRECIP
CLEARS THESE AREAS BY 12-13Z. SO I HAVE HELD ON TO SLGHT CHC AT
12Z IN THESE AREAS. REST OF FORECAST AREA WILL BE FREE OF PRECIP
BTWN 6Z AND 12Z.
AFTER THE PRECIP PASSES BY CLOUDS WILL CLEAR FOR A TIME THIS
MORNING. BUT COLD ADVECTION AT 850 MB AND SFC DEWPOINTS STILL IN
UPPER 30S SHUD LEAD TO SCT STRATOCUMULUS FORMING FOR A TIME BEFORE
ENUF DIURNAL MIXING TAKES PLACE BY MIDDAY TO MIX OUT THESE
CLOUDS. MODEL SOUNDINGS SUGGEST THIS AS WELL. THEN BY AFTERNOON
CIRRUS IN ADVANCE OF THE UPPER LEVEL LOW OVER TEXAS WILL ADVECT
NORTHEAST INTO THE UPPER CONFLUENT ZONE ALOFT WHICH CUTS ACRS
CENTRAL NY BY 18Z-21Z. SO WE EXPECT A SHIELD OF CIRRUS FROM SRN
NY ACROSS PA THIS AFTERNOON WHICH WILL BE THICK ENUF TO SPOIL A
MOSTLY SUNNY FORECAST. THESE CLOUDS WILL PUSH SOUTHEAST OF NE
PA/SERN NY THIS EVENING AS ANOTHER NRN BRANCH UPPER LEVEL SHORT
WAVE PUSHES SOUTHEAST FROM ONTARIO. SO... WE HAVE VARYING AMNTS
OF CLOUD COVER IN THE GRIDS FOR TODAY. NO POPS WARRANTING PRECIP
EXCEPT 12Z-14Z IN OUR FAR SE AND THESE ARE IN THE SLGHT CHC CAT.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH THURSDAY NIGHT/...
AFTER CIRRUS SHIELD PUSHES SOUTHEAST OF NE PA AND SERN NY THIS
EVENING AN UPPER LEVEL WAVE WILL PUSH SOUTHEAST INTO NRN NEW
ENGLAND LATER TONIGHT AND WEDNESDAY WITH NY AND PA BEING ON THE
SUBSDC SIDE OF THIS TROUGH WITH THE UPPER RDG AXIS OVER THE ERN
LAKES. THIS WILL SUPPORT HIGH PRESSURE TO BUILD SOUTHWARD FROM
CANADA WITH A DRIER AIR AND SEASONAL TEMPS FOR TONIGHT...WED AND
WED NGT.
BY THURSDAY THE SFC HIGH SHIFTS OFF THE NEW ENGLAND COAST AND A
SRLY FLOW OF AIR WILL DEVELOP OVER NY AND PA WITH MID TO HI CLOUDS
SPREADING FROM SW TO NE ACRS C NY AND NE PA. LOOKING AT THE
SYNOPTIC MODELS IT LOOKS LIKE ANY PRECIP WILL HOLD OFF UNTIL AFTER
00Z FRI SO THU LOOKS DRY AND MILDER WITH SRLY WINDS.
FOR THURSDAY NIGHT...THE GFS...EURO...CMC AND UKMET ALL SHOW
DECENT LOW-LEVEL THETA-E ADVECTION ARND 850 MB WHICH WILL ALLOW
FOR DESTABLIZATION AND SHRA ACVTY TO WORK INTO NY AND NRN PA FROM
W TO E OVRNGT. IT LOOKS LIKE WRN AND CNTRL NY GET INTO SOME SHRA
ACVTY BTWN 00Z AND 06Z AND NE PA AND SERN NY AFTER 6Z SO HAVE
WORKED POP TIMING TO REFLECT THIS. SHOWALTER INDICES SUGGEST THE
AMS WILL BE STABLE ENUF SO NO MENTION OF THUNDER AT THIS POINT.
QPF AMNTS APPEARS TO BE ON THE ORDER OF ABT .25 INCHES WHICH WILL
NOT CAUSE ANY HYDRO ISSUES. THE NAM IS THE ODD MODEL OUT WITH MUCH
DRIER LL AIR TO START AND NOT ENUF MOISTURE ADVTN TO LEAD TO MUCH
PRECIP. SO WENT WITH GFS/EURO/CMC AND UKMET IDEAS AND HAVE CHC
POPS SHRA THU NGT.
&&
.LONG TERM /FRIDAY THROUGH MONDAY/...
LONGWAVE RIDGING IS FORECAST TO BUILD ACROSS THE EASTERN U.S.
EARLY IN THE LONG TERM PERIOD BEFORE THE PATTERN BECOMES A BIT
TRICKIER LATE IN THE PERIOD AS MODEL SOLUTIONS DIVERGE
SIGNIFICANTLY INTO NEXT WEEKEND.
QUIET WEATHER EXPECTED THUR INTO FRIDAY WITH NEAR TO SLIGHTLY ABOVE
NORMAL TEMPS. THE CHANCE OF SHOWERS INCREASES SAT INTO MONDAY AS
SHORTWAVE ENERGY ROUND THE UPPER RIDGE NEXT WEEKEND. THE EXTENT OF
LOWER HEIGHTS...WHICH WOULD SUPPORT A WETTER SOLUTION...IS IN
QUESTION...WITH THE GFS SYSTEM KEEPING A STRONGER RIDGE. THE ECMWF
BRINGS AN UPPER LOW EASTWARD OUT OF THE PLAINS INTO THE REGION.
&&
.AVIATION /12Z TUESDAY THROUGH SATURDAY/...
MUCH DRIER LL AIR BHD THE COLD FNT AND ASSOCIATED PCPN THIS MRNG
RESULTING IN VFR CONDS ALL STATIONS. XCPTN IS SOME GND FOG AT ELM
BRINGING IFR VSBYS...WHICH SHD LIFT OFF QUICKLY. XPCT VFR CONDS
THRU THE TAF PD AS A SFC HIPRES BLDS INTO THE REGION. WV MVG THRU
THE OH VLY WILL KEEP HI CLDS OVER THE AREA HWVR.
.OUTLOOK...
WED/THUR...VFR.
THU NGT-SAT...POSSIBLE RESTRICTIONS IN -SHRA.
&&
.FIRE WEATHER...
DRIER AIR BEHIND A COLD FRONTAL PASSAGE WILL LEAD TO RELATIVE
HUMIDITIES FALLING BELOW 30 PERCENT THIS AFTERNOON. WINDS LOOK TO
BE LESS THAN 20 MPH ACROSS CENTRAL NEW YORK AND NORTHEAST
PENNSYLVANIA. IN ADDITION THE RAIN SHOWERS FROM LAST NIGHT AND
EARLY THIS MORNING SHOULD KEEP FINE FUELS ABOVE 10 PERCENT MOST OF
THE DAY. THEREFORE FIRE CONDITIONS ARE NOT EXPECTED TO APPROACH RED
FLAG CONDITIONS TODAY.
&&
.BGM WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NY...NONE.
&&
$$
SYNOPSIS...DJN
NEAR TERM...DJN
SHORT TERM...DJN
LONG TERM...
AVIATION...DGM
FIRE WEATHER...DJN
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
433 AM EDT TUE APR 14 2015
.SYNOPSIS...
A COLD FRONT WILL EXIT NORTHEAST PENNSYLVANIA AND SOUTHEAST NEW
YORK EARLY THIS MORNING TAKING THE SHOWERS WITH IT. AFTER THIS
FRONT PASSES BY, HIGH PRESSURE WILL PUSH DOWN FROM CANADA WITH
FAIR WEATHER AND SEASONAL TEMPERATURES FOR THE REST OF TODAY
THROUGH THURSDAY. THE NEXT CHANCE FOR RAIN SHOWERS WILL COME ON
THURSDAY NIGHT AS A WARM FRONT APPROACHES THE REGION.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
RADARS SHOW A BAND OF SHOWERS OF RAIN FROM ABOUT UTICA TO
BINGHAMTON AND TOWANDA AT THIS TIME AND WORKING EAST AS THE UPPER
LEVEL WAVE MOVES INTO THE EASTERN GREAT LAKES. THIS WAVE HAS
PROVIDED THE IMPETUS TO PUSH A COLD FRONT INTO NY AND PA. HI RES
MODELS CONTINUE TO INDICATE THAT THIS BAND OF SHRA WILL CONTINUE
EASTWARD AND CLEAR THE POCONOS TO WRN CATSKILLS BY AROUND 12Z AS
THE UPPER WAVE AND COLD FRONT MOVE THRU. THERE WAS NO LIGHTNING
DETECTED AND SHOWALTER INDICES WERE ABOVE 0C SO NO THUNDER
IN GRIDS. THE HRRR IS QUICKEST IN MOVING PRECIP THRU NE PA/SERN NY
WITH THE HI RES ARW AND NMM HOLDING THE PRECIP BACK A COUPLE
HOURS LONGER. THE RAP REFLECTIVITY FIELDS SHOW THAT THE PRECIP
CLEARS THESE AREAS BY 12-13Z. SO I HAVE HELD ON TO SLGHT CHC AT
12Z IN THESE AREAS. REST OF FORECAST AREA WILL BE FREE OF PRECIP
BTWN 6Z AND 12Z.
AFTER THE PRECIP PASSES BY CLOUDS WILL CLEAR FOR A TIME THIS
MORNING. BUT COLD ADVECTION AT 850 MB AND SFC DEWPOINTS STILL IN
UPPER 30S SHUD LEAD TO SCT STRATOCUMULUS FORMING FOR A TIME BEFORE
ENUF DIURNAL MIXING TAKES PLACE BY MIDDAY TO MIX OUT THESE
CLOUDS. MODEL SOUNDINGS SUGGEST THIS AS WELL. THEN BY AFTERNOON
CIRRUS IN ADVANCE OF THE UPPER LEVEL LOW OVER TEXAS WILL ADVECT
NORTHEAST INTO THE UPPER CONFLUENT ZONE ALOFT WHICH CUTS ACRS
CENTRAL NY BY 18Z-21Z. SO WE EXPECT A SHIELD OF CIRRUS FROM SRN
NY ACROSS PA THIS AFTERNOON WHICH WILL BE THICK ENUF TO SPOIL A
MOSTLY SUNNY FORECAST. THESE CLOUDS WILL PUSH SOUTHEAST OF NE
PA/SERN NY THIS EVENING AS ANOTHER NRN BRANCH UPPER LEVEL SHORT
WAVE PUSHES SOUTHEAST FROM ONTARIO. SO... WE HAVE VARYING AMNTS
OF CLOUD COVER IN THE GRIDS FOR TODAY. NO POPS WARRANTING PRECIP
EXCEPT 12Z-14Z IN OUR FAR SE AND THESE ARE IN THE SLGHT CHC CAT.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH THURSDAY NIGHT/...
AFTER CIRRUS SHIELD PUSHES SOUTHEAST OF NE PA AND SERN NY THIS
EVENING AN UPPER LEVEL WAVE WILL PUSH SOUTHEAST INTO NRN NEW
ENGLAND LATER TONIGHT AND WEDNESDAY WITH NY AND PA BEING ON THE
SUBSDC SIDE OF THIS TROUGH WITH THE UPPER RDG AXIS OVER THE ERN
LAKES. THIS WILL SUPPORT HIGH PRESSURE TO BUILD SOUTHWARD FROM
CANADA WITH A DRIER AIR AND SEASONAL TEMPS FOR TONIGHT...WED AND
WED NGT.
BY THURSDAY THE SFC HIGH SHIFTS OFF THE NEW ENGLAND COAST AND A
SRLY FLOW OF AIR WILL DEVELOP OVER NY AND PA WITH MID TO HI CLOUDS
SPREADING FROM SW TO NE ACRS C NY AND NE PA. LOOKING AT THE
SYNOPTIC MODELS IT LOOKS LIKE ANY PRECIP WILL HOLD OFF UNTIL AFTER
00Z FRI SO THU LOOKS DRY AND MILDER WITH SRLY WINDS.
FOR THURSDAY NIGHT...THE GFS...EURO...CMC AND UKMET ALL SHOW
DECENT LOW-LEVEL THETA-E ADVECTION ARND 850 MB WHICH WILL ALLOW
FOR DESTABLIZATION AND SHRA ACVTY TO WORK INTO NY AND NRN PA FROM
W TO E OVRNGT. IT LOOKS LIKE WRN AND CNTRL NY GET INTO SOME SHRA
ACVTY BTWN 00Z AND 06Z AND NE PA AND SERN NY AFTER 6Z SO HAVE
WORKED POP TIMING TO REFLECT THIS. SHOWALTER INDICES SUGGEST THE
AMS WILL BE STABLE ENUF SO NO MENTION OF THUNDER AT THIS POINT.
QPF AMNTS APPEARS TO BE ON THE ORDER OF ABT .25 INCHES WHICH WILL
NOT CAUSE ANY HYDRO ISSUES. THE NAM IS THE ODD MODEL OUT WITH MUCH
DRIER LL AIR TO START AND NOT ENUF MOISTURE ADVTN TO LEAD TO MUCH
PRECIP. SO WENT WITH GFS/EURO/CMC AND UKMET IDEAS AND HAVE CHC
POPS SHRA THU NGT.
&&
.LONG TERM /FRIDAY THROUGH MONDAY/...
LONGWAVE RIDGING IS FORECAST TO BUILD ACROSS THE EASTERN U.S.
EARLY IN THE LONG TERM PERIOD BEFORE THE PATTERN BECOMES A BIT
TRICKIER LATE IN THE PERIOD AS MODEL SOLUTIONS DIVERGE
SIGNIFICANTLY INTO NEXT WEEKEND.
QUIET WEATHER EXPECTED THUR INTO FRIDAY WITH NEAR TO SLIGHTLY ABOVE
NORMAL TEMPS. THE CHANCE OF SHOWERS INCREASES SAT INTO MONDAY AS
SHORTWAVE ENERGY ROUND THE UPPER RIDGE NEXT WEEKEND. THE EXTENT OF
LOWER HEIGHTS...WHICH WOULD SUPPORT A WETTER SOLUTION...IS IN
QUESTION...WITH THE GFS SYSTEM KEEPING A STRONGER RIDGE. THE ECMWF
BRINGS AN UPPER LOW EASTWARD OUT OF THE PLAINS INTO THE REGION.
&&
.AVIATION /09Z TUESDAY THROUGH SATURDAY/...
COLD FNT HAS MVD THRU THE NY STATIONS...APRCHG AVP ATTM. GNRL MVFR
CIGS WITH THE RAIN ASSOCITED WITH THE FNT. XPCT A 3 TO 4 HR PD OF
THE LWR CONDS AS THE FNT PASSES...WITH CONDS RETURNING TO VFR AT
NY STATIONS SHRTLY...CLSR TO 12Z AT AVP. REMAINDER OF THE TAF PD
WILL FEATURE VFR CONDS UNDER A HIGH CLD DECK...ALONG WITH LGT
WINDS.
.OUTLOOK...
TUE/WED/THUR...VFR.
THU NGT-SAT...POSSIBLE RESTRICTIONS IN -SHRA.
&&
.FIRE WEATHER...
DRIER AIR BEHIND A COLD FRONTAL PASSAGE WILL LEAD TO RELATIVE
HUMIDITIES FALLING BELOW 30 PERCENT THIS AFTERNOON. WINDS LOOK TO
BE LESS THAN 20 MPH ACROSS CENTRAL NEW YORK AND NORTHEAST
PENNSYLVANIA. IN ADDITION THE RAIN SHOWERS FROM LAST NIGHT AND
EARLY THIS MORNING SHOULD KEEP FINE FUELS ABOVE 10 PERCENT MOST OF
THE DAY. THEREFORE FIRE CONDITIONS ARE NOT EXPECTED TO APPROACH RED
FLAG CONDITIONS TODAY.
&&
.BGM WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NY...NONE.
&&
$$
SYNOPSIS...DJN
NEAR TERM...DJN
SHORT TERM...DJN
LONG TERM...
AVIATION...DGM/HEDEN
FIRE WEATHER...
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
415 AM EDT TUE APR 14 2015
.SYNOPSIS...
A COLD FRONT WILL EXIT NORTHEAST PENNSYLVANIA AND SOUTHEAST NEW
TORK EARLY THIS MORNING TAKING THE SHOWERS WITH IT. AFTER THIS
FRONT PASSES BY, HIGH PRESSURE WILL PUSH DOWN FROM CANADA WITH
FAIR WEATHER AND SEASONAL TEMPERATURES FOR THE REST OF TODAY
THROUGH THURSDAY. THE NEXT CHANCE FOR RAIN SHOWERS WILL COME ON
THURSDAY NIGHT AS A WARM FRONT APPROACHES THE REGION.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
RADARS SHOW A BAND OF SHOWERS OF RAIN FROM ABOUT UTICA TO
BINGHAMTON AND TOWANDA AT THIS TIME AND WORKING EAST AS THE UPPER
LEVEL WAVE MOVES INTO THE EASTERN GREAT LAKES. THIS WAVE HAS
PROVIDED THE IMPETUS TO PUSH A COLD FRONT INTO NY AND PA. HI RES
MODELS CONTINUE TO INDICATE THAT THIS BAND OF SHRA WILL CONTINUE
EASTWARD AND CLEAR THE POCONOS TO WRN CATSKILLS BY AROUND 12Z AS
THE UPPER WAVE AND COLD FRONT MOVE THRU. THERE WAS NO LIGHTNING
DETECTED AND SHOWALTER INDICES WERE ABOVE 0C SO NO THUNDER
IN GRIDS. THE HRRR IS QUICKEST IN MOVING PRECIP THRU NE PA/SERN NY
WITH THE HI RES ARW AND NMM HOLDING THE PRECIP BACK A COUPLE
HOURS LONGER. THE RAP REFLECTIVITY FIELDS SHOW THAT THE PRECIP
CLEARS THESE AREAS BY 12-13Z. SO I HAVE HELD ON TO SLGHT CHC AT
12Z IN THESE AREAS. REST OF FORECAST AREA WILL BE FREE OF PRECIP
BTWN 6Z AND 12Z.
AFTER THE PRECIP PASSES BY CLOUDS WILL CLEAR FOR A TIME THIS
MORNING. BUT COLD ADVECTION AT 850 MB AND SFC DEWPOINTS STILL IN
UPPER 30S SHUD LEAD TO SCT STRATOCUMULUS FORMING FOR A TIME BEFORE
ENUF DIURNAL MIXING TAKES PLACE BY MIDDAY TO MIX OUT THESE
CLOUDS. MODEL SOUNDINGS SUGGEST THIS AS WELL. THEN BY AFTERNOON
CIRRUS IN ADVANCE OF THE UPPER LEVEL LOW OVER TEXAS WILL ADVECT
NORTHEAST INTO THE UPPER CONFLUENT ZONE ALOFT WHICH CUTS ACRS
CENTRAL NY BY 18Z-21Z. SO WE EXPECT A SHIELD OF CIRRUS FROM SRN
NY ACROSS PA THIS AFTERNOON WHICH WILL BE THICK ENUF TO SPOIL A
MOSTLY SUNNY FORECAST. THESE CLOUDS WILL PUSH SOUTHEAST OF NE
PA/SERN NY THIS EVENING AS ANOTHER NRN BRANCH UPPER LEVEL SHORT
WAVE PUSHES SOUTHEAST FROM ONTARIO. SO... WE HAVE VARYING AMNTS
OF CLOUD COVER IN THE GRIDS FOR TODAY. NO POPS WARRANTING PRECIP
EXCEPT 12Z-14Z IN OUR FAR SE AND THESE ARE IN THE SLGHT CHC CAT.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH THURSDAY NIGHT/...
AFTER CIRRUS SHIELD PUSHES SOUTHEAST OF NE PA AND SERN NY THIS
EVENING AN UPPER LEVEL WAVE WILL PUSH SOUTHEAST INTO NRN NEW
ENGLAND LATER TONIGHT AND WEDNESDAY WITH NY AND PA BEING ON THE
SUBSDC SIDE OF THIS TROUGH WITH THE UPPER RDG AXIS OVER THE ERN
LAKES. THIS WILL SUPPORT HIGH PRESSURE TO BUILD SOUTHWARD FROM
CANADA WITH A DRIER AIR AND SEASONAL TEMPS FOR TONIGHT...WED AND
WED NGT.
BY THURSDAY THE SFC HIGH SHIFTS OFF THE NEW ENGLAND COAST AND A
SRLY FLOW OF AIR WILL DEVELOP OVER NY AND PA WITH MID TO HI CLOUDS
SPREADING FROM SW TO NE ACRS C NY AND NE PA. LOOKING AT THE
SYNOPTIC MODELS IT LOOKS LIKE ANY PRECIP WILL HOLD OFF UNTIL AFTER
00Z FRI SO THU LOOKS DRY AND MILDER WITH SRLY WINDS.
FOR THURSDAY NIGHT...THE GFS...EURO...CMC AND UKMET ALL SHOW
DECENT LOW-LEVEL THETA-E ADVECTION ARND 850 MB WHICH WILL ALLOW
FOR DESTABLIZATION AND SHRA ACVTY TO WORK INTO NY AND NRN PA FROM
W TO E OVRNGT. IT LOOKS LIKE WRN AND CNTRL NY GET INTO SOME SHRA
ACVTY BTWN 00Z AND 06Z AND NE PA AND SERN NY AFTER 6Z SO HAVE
WORKED POP TIMING TO REFLECT THIS. SHOWALTER INDICES SUGGEST THE
AMS WILL BE STABLE ENUF SO NO MENTION OF THUNDER AT THIS POINT.
QPF AMNTS APPEARS TO BE ON THE ORDER OF ABT .25 INCHES WHICH WILL
NOT CAUSE ANY HYDRO ISSUES. THE NAM IS THE ODD MODEL OUT WITH MUCH
DRIER LL AIR TO START AND NOT ENUF MOISTURE ADVTN TO LEAD TO MUCH
PRECIP. SO WENT WITH GFS/EURO/CMC AND UKMET IDEAS AND HAVE CHC
POPS SHRA THU NGT.
&&
.LONG TERM /FRIDAY THROUGH MONDAY/...
LONGWAVE RIDGING IS FORECAST TO BUILD ACROSS THE EASTERN U.S.
EARLY IN THE LONG TERM PERIOD BEFORE THE PATTERN BECOMES A BIT
TRICKIER LATE IN THE PERIOD AS MODEL SOLUTIONS DIVERGE
SIGNIFICANTLY INTO NEXT WEEKEND.
QUIET WEATHER EXPECTED THUR INTO FRIDAY WITH NEAR TO SLIGHTLY ABOVE
NORMAL TEMPS. THE CHANCE OF SHOWERS INCREASES SAT INTO MONDAY AS
SHORTWAVE ENERGY ROUND THE UPPER RIDGE NEXT WEEKEND. THE EXTENT OF
LOWER HEIGHTS...WHICH WOULD SUPPORT A WETTER SOLUTION...IS IN
QUESTION...WITH THE GFS SYSTEM KEEPING A STRONGER RIDGE. THE ECMWF
BRINGS AN UPPER LOW EASTWARD OUT OF THE PLAINS INTO THE REGION.
&&
.AVIATION /08Z TUESDAY THROUGH SATURDAY/...
COLD FNT HAS MVD THRU THE NY STATIONS...APRCHG AVP ATTM. GNRL MVFR
CIGS WITH THE RAIN ASSOCITED WITH THE FNT. XPCT A 3 TO 4 HR PD OF
THE LWR CONDS AS THE FNT PASSES...WITH CONDS RETURNING TO VFR AT
NY STATIONS SHRTLY...CLSR TO 12Z AT AVP. REMAINDER OF THE TAF PD
WILL FEATURE VFR CONDS UNDER A HIGH CLD DECK...ALONG WITH LGT
WINDS.
.OUTLOOK...
TUE/WED/THUR...VFR.
THU NGT-SAT...POSSIBLE RESTRICTIONS IN -SHRA.
&&
.FIRE WEATHER...
DRIER AIR BEHIND COLD FRONTAL PASSAGE WILL LEAD TO RELATIVE
HUMIDITIES FALLING BELOW 30 PERCENT THIS AFTERNOON. WINDS LOOK TO
BE BREEZY BUT MARGINAL. COORDINATED WITH SURROUNDING OFFICES WHO
MADE CONTACT WITH FORESTY OFFICIALS AND NO FIRE WEATHER HEADLINES
ARE NEEDED ATTM.
&&
.BGM WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NY...NONE.
&&
$$
SYNOPSIS...DJN
NEAR TERM...DJN
SHORT TERM...DJN
LONG TERM...
AVIATION...DGM/HEDEN
FIRE WEATHER...
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
246 AM EDT TUE APR 14 2015
.SYNOPSIS...
A COLD FRONT WILL EXIT NORTHEAST PENNSYLVANIA AND SOUTHEAST NEW
TORK EARLY THIS MORNING TAKING THE SHOWERS WITH IT. AFTER THIS
FRONT PASSES BY, HIGH PRESSURE WILL PUSH DOWN FROM CANADA WITH
FAIR WEATHER AND SEASONAL TEMPERATURES FOR THE REST OF TODAY
THROUGH THURSDAY. THE NEXT CHANCE FOR RAIN SHOWERS WILL COME ON
THURSDAY NIGHT AS A WARM FRONT APPROACHES THE REGION.
&&
.NEAR TERM /THROUGH TODAY/...
RADARS SHOW A BAND OF SHOWERS OF RAIN FROM ABOUT UTICA TO
BINGHAMTON AND TOWANDA AT THIS TIME AND WORKING EAST AS THE UPPER
LEVEL WAVE MOVES INTO THE EASTERN GREAT LAKES. THIS WAVE HAS
PROVIDED THE IMPETUS TO PUSH A COLD FRONT INTO NY AND PA. HI RES
MODELS CONTINUE TO INDICATE THAT THIS BAND OF SHRA WILL CONTINUE
EASTWARD AND CLEAR THE POCONOS TO WRN CATSKILLS BY AROUND 12Z AS
THE UPPER WAVE AND COLD FRONT MOVE THRU. THERE WAS NO LIGHTNING
DETECTED AND SHOWALTER INDICES WERE ABOVE 0C SO NO THUNDER
IN GRIDS. THE HRRR IS QUICKEST IN MOVING PRECIP THRU NE PA/SERN NY
WITH THE HI RES ARW AND NMM HOLDING THE PRECIP BACK A COUPLE
HOURS LONGER. THE RAP REFLECTIVITY FIELDS SHOW THAT THE PRECIP
CLEARS THESE AREAS BY 12-13Z. SO I HAVE HELD ON TO SLGHT CHC AT
12Z IN THESE AREAS. REST OF FORECAST AREA WILL BE FREE OF PRECIP
BTWN 6Z AND 12Z.
AFTER THE PRECIP PASSES BY CLOUDS WILL CLEAR FOR A TIME THIS
MORNING. BUT COLD ADVECTION AT 850 MB AND SFC DEWPOINTS STILL IN
UPPER 30S SHUD LEAD TO SCT STRATOCUMULUS FORMING FOR A TIME BEFORE
ENUF DIURNAL MIXING TAKES PLACE BY MIDDAY TO MIX OUT THESE
CLOUDS. MODEL SOUNDINGS SUGGEST THIS AS WELL. THEN BY AFTERNOON
CIRRUS IN ADVANCE OF THE UPPER LEVEL LOW OVER TEXAS WILL ADVECT
NORTHEAST INTO THE UPPER CONFLUENT ZONE ALOFT WHICH CUTS ACRS
CENTRAL NY BY 18Z-21Z. SO WE EXPECT A SHIELD OF CIRRUS FROM SRN
NY ACROSS PA THIS AFTERNOON WHICH WILL BE THICK ENUF TO SPOIL A
MOSTLY SUNNY FORECAST. THESE CLOUDS WILL PUSH SOUTHEAST OF NE
PA/SERN NY THIS EVENING AS ANOTHER NRN BRANCH UPPER LEVEL SHORT
WAVE PUSHES SOUTHEAST FROM ONTARIO. SO... WE HAVE VARYING AMNTS
OF CLOUD COVER IN THE GRIDS FOR TODAY. NO POPS WARRANTING PRECIP
EXCEPT 12Z-14Z IN OUR FAR SE AND THESE ARE IN THE SLGHT CHC CAT.
&&
.SHORT TERM /TONIGHT THROUGH WEDNESDAY NIGHT/...
AFTER FROPA ON TUESDAY...ASIDE FROM SOME ISOLATED SHRA LINGERING
IN THE POCONOS/WRN CATSKILLS BTWN 12Z AND 14Z REST OF C NY AND NE
PA WILL SEE NO PRECIP AS AGAIN MODEL CONSENSUS IS DRY. LOOKING AT
850 MB TEMPS AND SFC DEWPOINTS IT DOESN/T EVEN LOOK LIKE MUCH CU
FORMS TUE EXCEPT IN NC NY WHERE COLDER AIR AT 850 MB WILL BE
PRESENT TUESDAY. MUCH OF THE AREA TUESDAY WILL BE MOSTLY SUNNY AND
COOLER.
HIGH PRESSURE BUILDS IN FOR TUESDAY NIGHT AND LASTS THROUGH WED
AND WED NGT WITH FAIR WEATHER AND MODERATING TEMPERATURES WITH
MAXES REACHING INTO CLOSE TO OR ABOVE 60F EACH DAY.
&&
.LONG TERM /THURSDAY THROUGH MONDAY/...
LONGWAVE RIDGING IS FORECAST TO BUILD ACROSS THE EASTERN U.S.
EARLY IN THE LONG TERM PERIOD BEFORE THE PATTERN BECOMES A BIT
TRICKIER LATE IN THE PERIOD AS MODEL SOLUTIONS DIVERGE
SIGNIFICANTLY INTO NEXT WEEKEND.
QUIET WEATHER EXPECTED THUR INTO FRIDAY WITH NEAR TO SLIGHTLY ABOVE
NORMAL TEMPS. THE CHANCE OF SHOWERS INCREASES SAT INTO MONDAY AS
SHORTWAVE ENERGY ROUND THE UPPER RIDGE NEXT WEEKEND. THE EXTENT OF
LOWER HEIGHTS...WHICH WOULD SUPPORT A WETTER SOLUTION...IS IN
QUESTION...WITH THE GFS SYSTEM KEEPING A STRONGER RIDGE. THE ECMWF
BRINGS AN UPPER LOW EASTWARD OUT OF THE PLAINS INTO THE REGION.
&&
.AVIATION /06Z TUESDAY THROUGH SATURDAY/...
COLD FNT HAS MVD THRU THE NY STATIONS...APRCHG AVP ATTM. GNRL MVFR
CIGS WITH THE RAIN ASSOCITED WITH THE FNT. XPCT A 3 TO 4 HR PD OF
THE LWR CONDS AS THE FNT PASSES...WITH CONDS RETURNING TO VFR AT
NY STATIONS SHRTLY...CLSR TO 12Z AT AVP. REMAINDER OF THE TAF PD
WILL FEATURE VFR CONDS UNDER A HIGH CLD DECK...ALONG WITH LGT
WINDS.
.OUTLOOK...
TUE/WED/THUR...VFR.
THU NGT-SAT...POSSIBLE RESTRICTIONS IN -SHRA.
&&
.FIRE WEATHER...
DRIER AIR BEHIND TONIGHTS COLD FRONTAL PASSAGE WILL LEAD TO
RELATIVE HUMIDITIES FALLING BELOW 30 PERCENT TUESDAY AFTERNOON.
WINDS LOOK TO BE BREEZY BUT MARGINAL. COORDINATED WITH SURROUNDING
OFFICES WHO MADE CONTACT WITH FORESTY OFFICIALS AND NO FIRE
WEATHER HEADLINES ARE NEEDED ATTM.
&&
.BGM WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NY...NONE.
&&
$$
SYNOPSIS...DJN
NEAR TERM...DJN
SHORT TERM...
LONG TERM...
AVIATION...DGM/HEDEN
FIRE WEATHER...
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
1042 PM EDT WED APR 15 2015
.SYNOPSIS...
LOW PRESSURE WILL DEVELOP ALONG A FRONT STALLED ALONG THE GEORGIA
COAST TONIGHT...SLOWLY WEAKENING LATE THURSDAY AND FRIDAY. HIGH
PRESSURE OVER NEW ENGLAND WILL SHIFT EAST AND OFFSHORE THURSDAY. A
WARM FRONT WILL MOVE NORTH THROUGH THE CAROLINAS ON SUNDAY WITH A
COLD FRONT TO FOLLOW MONDAY NIGHT INTO TUESDAY.
&&
.NEAR TERM /UNTIL 6 AM THURSDAY MORNING/...
AS OF 1030 PM WEDNESDAY...THE WEATHER SITUATION IS UNFOLDING
PRETTY MUCH AS EXPECTED. THE SOLID MASS OF RAIN HAS CLEARED THE
PEE DEE COUNTIES BUT RAIN CONTINUES TO FALL ACROSS
WHITEVILLE...SOUTHPORT AND WILMINGTON. THIS AREA SHOULD MOVE OFF
THE COAST IN THE NEXT 2 HOURS...LEAVING MUCH WEAKER FORCING FOR
THE OVERNIGHT NIGHT. LATEST HRRR AND HRRRX MODELS STILL SUGGEST
THE BEST POTENTIAL FOR OVERNIGHT RAIN WILL BE NORTH OF A LINE FROM
FLORENCE TO DILLON...TO ELIZABETHTOWN AND BURGAW...COINCIDENT
WITH THE BETTER 700 MB MOISTURE AND RESIDUAL ISENTROPIC LIFT ON
THE SYNOPTIC MODELS. THERE IS ALSO SMALL POSITIVE ELEVATED
INSTABILITY ON THE ORDER OF 100 J/KG WHICH COULD HELP SUPPORT
SHOWERS GIVEN SUFFICIENT SYNOPTIC TRIGGERING. FEW CHANGES ARE
NEEDED TO LOW TEMPERATURE FORECASTS OR WINDS. DISCUSSION FROM 730
PM FOLLOWS...
A STALLED FRONT JUST SOUTH OF SAVANNAH WILL DEVELOP AN AREA OF LOW
PRESSURE IN THE NEXT FEW HOURS. THIS LOW WILL NOT STRAY TOO FAR
OFFSHORE OVER THE NEXT 24 HOURS...BUT WILL MAINTAIN A STEADY
NORTHEAST WIND. SURFACE HIGH PRESSURE OVER SOUTHEASTERN CANADA
WILL SLIDE SOUTHEAST INTO NEW ENGLAND TONIGHT. THIS HIGH WILL
EXTEND A RIDGE AXIS SOUTHWARD INTO THE CAROLINAS...COMPRESSING THE
PRESSURE GRADIENT UP AGAINST THE LOW DEVELOPING OFF THE GEORGIA
COAST.
A COMPLEX UPPER LEVEL PATTERN ACROSS THE WESTERN U.S. HAS THE JET
STREAM SPLIT INTO TWO SEGMENTS. THE SOUTHERN STREAM WILL BRING
SEVERAL DISTURBANCES ACROSS THE CAROLINAS OVER THE NEXT 36-48
HOURS. ONE OF THESE DISTURBANCES IS MOVING ACROSS INTERSTATE 95
NOW PRODUCING THE LARGE SWATH OF RAIN NOW SEEN ON RADAR. THIS
FEATURE SHOULD WORK ITS WAY TO THE COAST AROUND MIDNIGHT...AND I
HAVE RAISED FORECAST POPS TO 100 PERCENT AREA-WIDE WITH 0.2 TO 0.4
INCHES OF RAIN EXPECTED OVER THE NEXT 12 HOURS. PLENTY OF MID-
LEVEL MOISTURE SHOULD HANG AROUND AFTER MIDNIGHT WITH JUST ENOUGH
WEAK ISENTROPIC LIFT PLUS ELEVATED INSTABILITY TO MAINTAIN SHOWERS
AFTER MIDNIGHT...ESPECIALLY NORTH OF FLORENCE AND MYRTLE BEACH.
LOW-LEVEL NORTHEAST WINDS WILL DRAG COOLER AIR SOUTHWARD
TONIGHT...WITH LOWS AWAY FROM THE COAST FALLING TO NEAR 50.
VARYING DEGREES OF MARINE INFLUENCE WILL KEEP THE IMMEDIATE COAST
WARMER WITH LOWS IN THE MID 50S POSSIBLE.
&&
.SHORT TERM /6 AM THURSDAY MORNING THROUGH FRIDAY NIGHT/...
AS OF 300 PM WEDNESDAY...THE FORECAST HAS BECOME NO LESS COMPLICATED
AND IN FACT...IN SOME RESPECTS...MODELS HAVE DIVERGED EVEN FURTHER
IN THE LAST 24 HOURS. THE GFS SOLUTION LOOKS VERY DIFFERENT FROM
PREVIOUS RUNS. THE NAM SOLUTION LOOKS SIMILAR TO PREVIOUS
THINKING...BUT THE PROGRESSION OF OFFSHORE LOW PRESSURE IS SLOWER
AND FURTHER EASTWARD THAN 24 HOURS AGO AND CERTAINLY MUCH STRONGER.
THE CANADIAN IS CONSIDERABLY SLOWER AND WEAKER THAN THE NAM AS IS
THE EUROPEAN...BUT BOTH DO CLOSE OFF LOW PRESSURE ALONG THE COAST OF
SOUTH CAROLINA. SLOWER SEEMS REASONABLE GIVEN THE STRENGTH OF HIGH
PRESSURE TO THE NORTH AND RESULTING WEDGE...THUS THE BEST WE CAN DO
AT THIS POINT IS TO GO ALONG WITH PERSISTENCE...BUT SLOW PROGRESSION.
WILL INCLUDE HIGHEST POPS THU ALONG THE COAST AND UP TO CATEGORICAL
THU MORNING ALONG THE CAPE FEAR COAST DUE TO STRENGTH OF ISENTROPIC
LIFT COUPLED WITH THE LIFT ASSOCIATED WITH LOW PRESSURE/TROUGH. WILL
THEN TREND POPS LOWER THU AFTERNOON AND NIGHT FROM SW TO NE WITH A
LINGERING RISK ALONG THE CAPE FEAR COAST FRI MORNING. GIVEN
PROXIMITY OF COASTAL TROUGH AND ELEVATED INSTABILITY...WILL INCLUDE
MENTION OF THUNDER FOR PORTIONS OF THE FORECAST AREA.
THE MOISTURE PROFILES DRY OUT CONSIDERABLY AS A RIDGE OF HIGH
PRESSURE ALOFT BUILDS TO THE COAST FROM THE WEST TOWARD THE END OF
THE PERIOD. WILL FINALLY DROP POPS BELOW THRESHOLD FRI AFTERNOON AND
NIGHT...EVEN ALONG THE SEABREEZE BOUNDARY.
BELOW NORMAL HIGH TEMPS ARE EXPECTED AGAIN ON THU AS WEDGE KEEPS LOW-
LEVEL MOISTURE TRAPPED BENEATH INVERSION. HIGHS WILL ONLY BE IN THE
LOWER TO MID 60S. DEVELOPING SUNSHINE ON FRI SHOULD ALLOW TEMPS TO
RETURN TO MORE SEASONABLE LEVELS...LOW AND MID 70S. LOWS THIS PERIOD
WILL BE MAINLY IN THE 50S.
&&
.LONG TERM /SATURDAY THROUGH WEDNESDAY/...
AS OF 300 PM WEDNESDAY...GUIDANCE HAS SHIFTED PRETTY DRAMATICALLY
FROM JUST YESTERDAY...LEADING TO ENHANCED UNCERTAINTY DURING THE
EXTENDED. LARGE CLOSED LOW ACROSS THE SOUTHWEST WILL ONLY VERY
SLOWLY FILL AND EJECT TO THE NORTHEAST THROUGH THE WEEKEND...PHASING
WITH A DEEPENING NORTHERN STREAM CUTOFF LOW ACROSS THE GREAT LAKES
LATE MONDAY. THIS FEATURE WILL THEN AMPLIFY AND STALL ACROSS THE
GREAT LAKES THROUGH THE MIDDLE OF NEXT WEEK...PRODUCING 500MB
HEIGHTS OF -2 TO -3 SD`S BELOW CLIMO ACROSS THE NORTHEAST AND INTO
THE MID-ATLANTIC.
INITIALLY THE EXTENDED WILL BE WARM AND PLEASANT. SATURDAY IS
SHAPING UP TO BE A GORGEOUS DAY LOCALLY...WITH HIGHS ABOVE CLIMO AND
A LOT OF SUNSHINE. MOISTURE RETURNS SUNDAY IN A PRE-FRONTAL AIR MASS
WHICH WILL CONTINUE INTO MONDAY AHEAD OF A COLD FRONT. SUNDAY AND
MONDAY WILL BOTH FEATURE ABOVE CLIMO TEMPS...BUT WITH INCREASING
RAIN CHANCES AHEAD OF THE COLD FRONT. ATTM THE FRONT DOES NOT LOOK
TO BE STRONGLY FORCED SO WIDESPREAD CONVECTION IS NOT ANTICIPATED
MONDAY EVENING WITH THE FROPA. COOLER HIGH PRESSURE WILL BUILD IN
BEHIND THE FRONT FOR TUE/WED OF NEXT WEEK WITH TEMPS RETURNING TO
SEASONABLE LEVELS.
&&
.AVIATION /00Z THURSDAY THROUGH MONDAY/...
AS OF 00Z...MOST TERMINALS IN VFR OR MVFR CATEGORY ATTM WITH A
BAND OF LIGHT TO MDT RAIN MOVING THROUGH THE AREA. EXPECT TO SEE
CONDITIONS DETERIORATE TO IFR AGAIN OVERNIGHT AFTER MAIN BAND OF
RAIN MOVES THROUGH AND PRECIP BECOMES MORE ISOLATED TO SCATTERED
IN NATURE. AN AREA OF LOW PRESSURE WILL BRING ADDITIONAL RAINFALL
AFTER DAY BREAK THURSDAY WHICH SHOULD ALLOW IFR TO MVFR CONDITIONS
TO PERSIST FOR MUCH OF THE REMAINDER OF THE FORECAST PERIOD.
EXTENDED OUTLOOK...PREDOMINATELY IFR CONDITIONS ARE EXPECTED INTO
EARLY FRIDAY MORNING WITH THE WEDGE. IMPROVING CONDITIONS DURING THE
DAY FRI. DETERIORATING CONDITIONS AGAIN SATURDAY NIGHT THROUGH
SUNDAY WITH A SLOW MOVING FRONT. SLIGHT CHANCE FOR SHOWERS MONDAY.
&&
.MARINE...
NEAR TERM /THROUGH TONIGHT/...
AS OF 1030 PM WEDNESDAY...STRONG NE WINDS HAVE QUICKLY DEVELOPED
THIS EVENING. RECENT WIND GUSTS INCLUDE 31 KNOTS AT SPRINGMAID
PIER IN MYRTLE BEACH...24 KNOTS ON BALD HEAD ISLAND...AND 23
KNOTS AT WRIGHTSVILLE BEACH. SEAS OUT AT THE FRYING PAN SHOALS
BUOY HAVE ALREADY REACHED 8 FEET...WITH SEAS NOW PASSING 5 FEET AT
BOTH NEARSHORE BUOYS NEAR CAPE FEAR. THIS UPDATE BACKED WINDS
AROUND MORE NORTHERLY NEARSHORE AND INCREASE SEA HEIGHTS
SLIGHTLY...ALL BASED ON CURRENT OBSERVATIONS. DISCUSSION FROM 730
PM FOLLOWS...
A FRONT STALLED JUST SOUTH OF SAVANNAH EXTENDS EAST WELL OFF THE
COAST. WEAK LOW PRESSURE WILL DEVELOP ALONG THE FRONT
TONIGHT...WHILE HIGH PRESSURE OVER NEW ENGLAND RIDGES SOUTHWARD
DOWN THE COAST. THE CAROLINAS WILL BE CAUGHT IN BETWEEN THESE TWO
SYSTEMS...WITH INCREASING EAST-NORTHEAST WINDS THE RESULT.
THE 18Z GFS APPEARS TO BE THE BEST INITIALIZED OF OUR MODELS THIS
EVENING...AND ITS FORECAST WINDS HAPPEN TO BE THE STRONGEST
TONIGHT...INDICATING WINDS NEARSHORE INCREASING TO 20-25 KT AND
25-30 KT AWAY FROM SHORE. THIS IS SLIGHTLY HIGHER THAN THE
PREVIOUS FORECAST HAD. LATEST CHECK OF BUOYS INDICATES SEAS ARE
INCREASING A BIT FASTER THAN EARLIER THOUGHT. I HAVE ADDED ABOUT
ONE FOOT TO THE PREVIOUS FORECAST...WITH SEAS NOW EXPECTED TO
BUILD TO 6-8 FEET OUT AT 20 MILES DISTANCE FROM SHORE...WITH 4-7
FEET EXPECTED CLOSER TO SHORE.
SHORT TERM /THURSDAY THROUGH FRIDAY NIGHT/...
AS OF 300 PM WEDNESDAY...ONGOING SMALL CRAFT ADVISORY CONDITIONS ARE
EXPECTED AT THE BEGINNING OF THE PERIOD AS LOW PRESSURE MOVES UP THE
SOUTHEAST COAST. THE PRESSURE GRADIENT BETWEEN DEVELOPING LOW
PRESSURE AND THE STRONG HIGH TO THE NORTH WILL ALLOW A TIGHT
PRESSURE GRADIENT TO PERSIST INTO THU AND THIS IS WHEN WE EXPECT THE
STRONGEST WINDS AND HIGHEST SEAS...UP TO 20 TO 30 KT...HIGHEST
NORTHERN WATERS AND SEAS UP TO 5 TO 8 FT THROUGHOUT. AS THE PRESSURE
GRADIENT SLACKENS AND LOW PRESSURE MOVES TO OUR N...WINDS AND SEAS
WILL SUBSIDE THU NIGHT AND FRI WITH THIS TREND PERSISTING INTO FRI
NIGHT. ENE WINDS THU WILL BACK TO NE THU NIGHT WITH NNE TO NE
WINDS THEN PERSISTING THROUGH THE END OF THE PERIOD.
LONG TERM /SATURDAY THROUGH MONDAY/...
AS OF 300 PM WEDNESDAY...HIGH PRESSURE WILL BUILD DOWN THE COAST AND
THEN MOVE OFFSHORE SATURDAY...CREATING A WEAK PRESSURE GRADIENT AND
WINDS SHIFTING FROM NE EARLY...TO E/SE LATE. WINDS SPEEDS THEN
STEADILY INCREASE SUNDAY AS THE GRADIENT STARTS TO PINCH AHEAD OF AN
APPROACHING COLD FRONT...BECOMING S/SW AT AROUND 15 KTS MOST OF
SUNDAY...AND THEN SW AT 15-20 KTS ON MONDAY DIRECTLY AHEAD OF THE
FROPA. COLD FRONT WILL CROSS THE WATERS AT THE VERY END OF THE
PERIOD WITH A WIND SHIFT TO THE NW AT 10-15 KTS. ALTHOUGH A WEAK SE
GROUND SWELL WILL BE PRESENT IN THE SPECTRUM DURING THE
EXTENDED...MUCH OF THE WAVE AMPLITUDE WILL BE FORMED VIA WIND
WAVES...AND SEAS WILL BE 2-3 FT SATURDAY...BUILDING TO 3-5 FT SUNDAY
AND MONDAY AHEAD OF THE COLD FRONT.
&&
.ILM WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
NC...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 2 AM EDT FRIDAY FOR AMZ250-252-254-
256.
&&
$$
SYNOPSIS...TRA
NEAR TERM...TRA
SHORT TERM...RJD
LONG TERM...JDW
AVIATION...RAN
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
320 PM EDT TUE APR 14 2015
.SYNOPSIS...
A COLD FRONT WILL SAG SOUTH AND MOVE ACROSS THE AREA LATE TONIGHT
AND WEDNESDAY MORNING. A WEDGE OF HIGH PRESSURE...PUSHING IN FROM
THE NORTH...WILL KEEP THE WEATHER UNSETTLED WEDNESDAY. LOW PRESSURE
IS EXPECTED TO MOVE UP THE SOUTHEAST COAST THURSDAY INTO FRIDAY...
KEEPING SHOWERS IN THE FORECAST. IT WILL BE WARM AND UNSETTLED
DURING THE WEEKEND AND INTO EARLY NEXT WEEK. A COLD FRONT MAY MOVE
ACROSS THE AREA ON TUESDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 200 PM TUESDAY...ENTRENCHED IN WARM AND MOIST AIR MASS
AHEAD OF A COLD FRONT WHICH WILL DROP SOUTH THROUGH NORTH CAROLINA
THROUGH TONIGHT. DEWPOINTS IN THE MID 60S TO AROUND 70 THIS
AFTERNOON AND TEMPS BETWEEN 75 TO 80 MOST PLACES AWAY FROM THE
COAST. MAY SEE SOME SKIES BRIGHTEN THIS AFTERNOON WHICH COULD HELP
PROPEL TEMPS UP A LITTLE FURTHER. DEEP MOISTURE THROUGH THIS
AFTERNOON WITH PCP WATER VALUES UP CLOSE TO 2 INCHES AND SOUNDING
PARAMETERS ALL POINTING TO POTENTIAL FOR TSTMS. THE PRIMARY FOCUS
WOULD BE FURTHER NW INTO CENTRAL CAROLINAS AS WAVE OF LOW PRESSURE
MOVES UP THROUGH THE TENNESSEE VALLEY TOWARD THE NORTHEAST...BUT A
SHORTWAVE MOVING THROUGH WILL BE THE MAIN DRIVER TO ENHANCE ANY
CONVECTION OVER OUR LOCAL FORECAST AREA THROUGH EARLY THIS EVE.
HRRR AND NAM SHOWING CONVECTION PICKING UP BETWEEN 19Z AND 00Z
MOVING ACROSS FROM SOUTHWEST TO NORTHEAST. WINDS WILL BEGIN TO
VEER THROUGH THE LOW LEVELS AND MAY SEE GREATER WIND SHEAR WITH
ANY STORMS THAT DEVELOP THROUGH LATE THIS AFTERNOON. POTENTIAL
WILL EXIST ESPECIALLY THROUGH LATE THIS AFTN TO SEE SOME ISOLATED
STRONGER STORMS. SPC HAS NORTHWEST PORTIONS OF FORECAST AREA IN
MARGINAL RISK WITH STRONGER WIND THREAT...BUT MAIN THREAT AREA
SHOULD REMAIN FARTHER TO THE NORTH AND WEST.
ONCE THIS SHORTWAVE RIDES OFF TO THE NORTHEAST THIS
EVENING...SUBSIDENCE AND DRIER AIR WILL MAKE ITS WAY INTO THE AREA
ON THE BACK END. WINDS SHIFT TO A MORE WESTERLY DIRECTION THROUGH
THE LOW LEVELS AS COLD FRONT DROPS SOUTH AFTER MIDNIGHT. GFS
SHOWS A DROP IN PCP WATER DOWN TO 1.5 INCHES BY THIS EVENING. HRRR
SHOWS SHOWERS MOVING OFF TO THE NORTHEAST LEAVING ONLY ISOLATED
SHWRS OVER LOCAL AREA UNTIL COLD FRONT REACHES THE AREA LATER IN
THE NIGHT.
COLD FRONT WILL DROP SOUTH THROUGH TONIGHT WITH WINDS SHIFTING
AROUND FURTHER...BECOMING NORTH BEHIND FRONT. SHOULD SEE ANOTHER
POTENTIAL FOR INCREASED SHOWER ACTIVITY AS COLD FRONT MOVES
THROUGH AREA OVERNIGHT...ESPECIALLY BETWEEN 3 AM AND DAYBREAK.
COOLER AIR WILL MAKE ITS WAY IN BEHIND FRONT WHICH SHOULD BE
RUNNING WEST TO EAST ACROSS SOUTH CAROLINA BY MORNING. TEMPS
SHOULD DROP BELOW 60 BY DAYBREAK OVER MOST OF AREA.
&&
.SHORT TERM /WEDNESDAY THROUGH THURSDAY NIGHT/...
AS OF 300 PM TUESDAY...COMPLICATED FORECAST WITH MANY MOVING
PARTS AND GIVEN THE VARIOUS MODEL SOLUTIONS...IT DOES MAKE IT
DIFFICULT TO BE OVERLY CONFIDENT AS TO WHEN TO INCLUDE THE HIGHEST
POPS. HIGHLY CONFIDENT RAINFALL WILL OCCUR AT ALL LOCATIONS AT
SOME POINT DURING THIS PERIOD. A COLD FRONT WILL BE SAGGING
SOUTHWARD THROUGH THE FORECAST AREA WED MORNING WITH A SHORT-LIVED
WEDGE OF HIGH PRESSURE BUILDING SOUTHWARD INTO THE FORECAST WED
AFTERNOON AND NIGHT. WEAK ISENTROPIC UPGLIDE WILL DEVELOP IN THE
WAKE OF THE FRONT AND SO WILL KEEP A PESSIMISTIC FORECAST WITH
MAINLY CLOUDY SKIES AND LIKELY POPS.
SEVERAL WEAK SHORTWAVES WILL MOVE THROUGH THE FLOW...BUT AGAIN THE
TIMING AND POSITIONAL DISCREPANCIES PERSIST. FINALLY...LOW
PRESSURE IS EXPECTED TO DEVELOP TO OUR SOUTH AND MOVE SLOWLY UP
THE COAST...PERHAPS MAKING ITS CLOSEST APPROACH THU NIGHT AND
FRI. ASSOCIATED LIFT SHOULD BE HIGHEST ON THE COAST DURING THIS
TIME...BUT WITH DEEP MOISTURE RETURNING...WILL KEEP THE POPS HIGH
THROUGHOUT.
CLOUD COVER WILL SHRINK THE DIURNAL RANGE WITH HIGH TEMPS
REMAINING NEAR OR SLIGHTLY BELOW NORMAL AND LOW TEMPS REMAINING
ABOVE NORMAL.
&&
.LONG TERM /FRIDAY THROUGH TUESDAY/...
AS OF 300 PM TUESDAY...DEEP MID-LEVEL CLOSED LOW ACROSS TX/NM
WILL LIFT SLOWLY NE WHILE OPENING THROUGH THE PERIOD. GUIDANCE
DIFFERS SIGNIFICANTLY WITHIN THE MEDIUM RANGE IN THE EVOLUTION OF
THIS FEATURE...AS THE GFS DIGS IT QUITE DEEP TOWARDS THE GOM AND
BRINGS A POTENT VORT IMPULSE AND ASSOCIATED COLD FRONT ACROSS THE
CAROLINAS SUNDAY...WHILE THE ECMWF KEEP THE FEATURE DEFLECTED WELL
TO THE NORTH AND THUS CREATES NO NOTICEABLE AIR MASS CHANGE DURING
THE PERIOD. HESITATE TO MAKE ANY SIGNIFICANT CHANGES TO THE
EXTENDED WHICH WERE BASED PRIMARILY ON THE GFS...BUT WITH A STRONG
RIDGE IN PLACE ACROSS THE SOUTHEAST LATE IN THE WEEK...WILL BLEND
SOME SUPPORT TO THE ECM SOLUTION. THIS PRODUCES SEASONABLE TO
ABOVE SEASONABLE TEMPERATURES THROUGH THE EXTENDED...ALONG WITH A
CHANCE FOR RAINFALL EACH DAY AS A REMNANT FRONT WAVERS IN THE
VICINITY ACTING AS A FOCUS FOR SHOWERS WITHIN DEEP SW FLOW. BEST
CHANCE FOR RAINFALL WILL BE THE FIRST HALF OF THE PERIOD
HOWEVER...THANKS TO A WEAK WAVE OF LOW PRESSURE OFFSHORE FRIDAY
WITH A RENEWED PUSH OF THE STALLED BOUNDARY BEHIND IT. A DRYING
TREND LOOKS TO DEVELOP EARLY NEXT WEEK.
&&
.AVIATION /18Z TUESDAY THROUGH SUNDAY/...
AS OF 18Z...STILL NOT VERY CONFIDENT ABOUT CONVECTION THIS
AFTERNOON. WILL LEAN ON THE HRRR MODEL THAT SHOWS A PRETTY DECENT
BAND OF CONVECTION SETTING UP BETWEEN FLO AND THE MYRTLES BY 20Z.
THIS ACTIVITY IS COURTESY OF LOW PRESSURE CENTERED WEST OF THE
REGION WITH SPOKES OF VORTICITY ROTATING EAST OF THE LOW. THE LAST
VORT WILL MOVE NORTHEAST AND OUT OF THE REGION LATE THIS
AFTERNOON...FOLLOWED BY CLEARING SKIES.
TONIGHT...STRATUS WILL AGAIN SET UP...WITH WINDS SHIFTING TO THE
NORTH LATE IN THE FORECAST PERIOD AS A BACK DOOR FRONT DROPS IN.
THERE WILL LIKELY BE SOME PRECIP ALONG AND BEHIND THE
FRONT...PROBABLY MORE DRIZZLE THAN RAIN.
EXTENDED OUTLOOK...PREDOMINATELY IFR CONDITIONS ARE EXPECTED WED
AFTERNOON THROUGH THURSDAY WITH A WEDGE. IMPROVING CONDITIONS FRI.
DETERIORATING CONDITIONS AGAIN SATURDAY AFTERNOON THROUGH SUNDAY
WITH A COLD FRONT.
&&
.MARINE...
NEAR TERM /THROUGH TONIGHT/...
AS OF 200 PM TUESDAY...SOUTH TO SW WINDS WILL CONTINUE THROUGH
MOST OF TONIGHT IN ADVANCE OF COLD FRONT DROPPING DOWN FROM THE
NORTH. AS THE FRONT DRAWS CLOSER...THE WINDS WILL PICK UP SLIGHTLY
AS THEY VEER FURTHER TO THE SOUTHWEST AND EVENTUALLY AROUND TO THE
NORTH BEHIND THE FRONT. LOOKS LIKE THE COLD FRONT WILL RUN WEST TO
EAST ACROSS SOUTH CAROLINA BISECTING LOCAL WATERS BY DAYBREAK.
WINDS WILL CONTINUE IN THE GENERAL 10 TO 15 KT RANGE...WITH SEAS
RANGING FROM 2 TO 4 FT MOST PLACES WITH A SLIGHT RISE OVERNIGHT.
SHORT TERM /WEDNESDAY THROUGH THURSDAY NIGHT/...
AS OF 300 PM TUESDAY...A NE SURGE WILL GET UNDERWAY IN THE WAKE OF
A SOUTHWARD SAGGING COLD FRONT WEDNESDAY MORNING. HIGH PRESSURE
WILL BUILD SOUTHWARD LATE WED NIGHT INTO THU. AS LOW PRESSURE
DEVELOPS TO OUR SOUTH AND MOVES UP THE COAST...THE PRESSURE
GRADIENT WILL TIGHTEN...ESPECIALLY WED NIGHT INTO THU AND THIS IS
WHEN I WILL FORECAST THE STRONGEST WINDS AND HIGHEST SEAS...UP TO
20 TO 25 KT AND 5 TO 8 FT SEAS. I EXPECT A PERIOD OF SMALL CRAFT
ADVISORY CONDITIONS WILL DEVELOP BY WED EVE AND THEN PERSIST INTO
THU WITH SEAS PERHAPS NOT SUBSIDING BELOW ADVISORY CRITERIA UNTIL
THU NIGHT...PERHAPS NOT UNTIL FRI MORNING ACROSS THE NORTHERN
WATERS.
LONG TERM /FRIDAY THROUGH SUNDAY/...
AS OF 300 PM TUESDAY...WEAK LOW PRESSURE WILL BE NEARLY DIRECTLY
OVERHEAD FRIDAY MORNING...WITH MOST OF THE STRONG WINDS/TIGHT
GRADIENT NORTH OF THE REGION TO START THE PERIOD. WINDS TURN TO AN
OFFSHORE COMPONENT MUCH OF FRIDAY INTO SATURDAY BEHIND THIS LOW
PRESSURE...BEFORE BERMUDA TYPE RIDGE BECOMES THE DOMINANT FEATURE
ONCE AGAIN WITH SW FLOW PERSISTING THROUGH SATURDAY...BEFORE
QUICKLY BECOMING NE AS A COLD FRONT DROPS BACK ACROSS THE WATERS
SUNDAY. SPEEDS WILL BE AROUND 10 KTS OR LESS REGARDLESS OF
DIRECTION. WAVE HEIGHTS WILL BE HIGHEST FRIDAY MORNING AS RESIDUAL
WIND WAVE/SWELL FROM FRIDAY SLOWLY FALLS ACROSS THE WATERS...AND
3-5 FT SEAS WILL BE COMMON THE FIRST HALF OF FRIDAY. SEAS WILL
THEN FALL TO 2-4 FT SATURDAY AND SUNDAY...ALTHOUGH THE PRIMARY
WAVE WILL FOLLOW THE WINDS THROUGH THE WKND.
&&
.ILM WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
NC...NONE.
MARINE...NONE.
&&
$$
NEAR TERM...RGZ
SHORT TERM...RJD
LONG TERM...JDW
AVIATION...RGZ/DL
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
214 PM EDT TUE APR 14 2015
.SYNOPSIS...
UNSETTLED CONDITIONS WILL PERSIST TODAY AS A SERIES OF WEAK
DISTURBANCES MOVE ACROSS. A COLD FRONT WILL CROSS THE AREA EARLY
WEDNESDAY MORNING...STALLING TO OUR SOUTH ON THURSDAY. LOW
PRESSURE MAY DEVELOP ALONG THE FRONT THURSDAY INTO FRIDAY..LIFTING
NORTH OF THE AREA SATURDAY. A COLD FRONT WILL MOVE ACROSS THE
CAROLINAS FROM THE WEST LATE SATURDAY. HIGH PRESSURE WILL BUILD IN
FROM THE WEST SUNDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 200 PM TUESDAY...ENTRENCHED IN WARM AND MOIST AIR MASS
AHEAD OF A COLD FRONT WHICH WILL DROP SOUTH THROUGH NORTH CAROLINA
THROUGH TONIGHT. DEWPOINTS IN THE MID 60S TO AROUND 70 THIS
AFTERNOON AND TEMPS BETWEEN 75 TO 80 MOST PLACES AWAY FROM THE
COAST. MAY SEE SOME SKIES BRIGHTEN THIS AFTERNOON WHICH COULD HELP
PROPEL TEMPS UP A LITTLE FURTHER. DEEP MOISTURE THROUGH THIS
AFTERNOON WITH PCP WATER VALUES UP CLOSE TO 2 INCHES AND SOUNDING
PARAMETERS ALL POINTING TO POTENTIAL FOR TSTMS. THE PRIMARY FOCUS
WOULD BE FURTHER NW INTO CENTRAL CAROLINAS AS WAVE OF LOW PRESSURE
MOVES UP THROUGH THE TENNESSEE VALLEY TOWARD THE NORTHEAST...BUT A
SHORTWAVE MOVING THROUGH WILL BE THE MAIN DRIVER TO ENHANCE ANY
CONVECTION OVER OUR LOCAL FORECAST AREA THROUGH EARLY THIS EVE.
HRRR AND NAM SHOWING CONVECTION PICKING UP BETWEEN 19Z AND 00Z
MOVING ACROSS FROM SOUTHWEST TO NORTHEAST. WINDS WILL BEGIN TO
VEER THROUGH THE LOW LEVELS AND MAY SEE GREATER WIND SHEAR WITH
ANY STORMS THAT DEVELOP THROUGH LATE THIS AFTERNOON. POTENTIAL
WILL EXIST ESPECIALLY THROUGH LATE THIS AFTN TO SEE SOME ISOLATED
STRONGER STORMS. SPC HAS NORTHWEST PORTIONS OF FORECAST AREA IN
MARGINAL RISK WITH STRONGER WIND THREAT...BUT MAIN THREAT AREA
SHOULD REMAIN FARTHER TO THE NORTH AND WEST.
ONCE THIS SHORTWAVE RIDES OFF TO THE NORTHEAST THIS
EVENING...SUBSIDENCE AND DRIER AIR WILL MAKE ITS WAY INTO THE AREA
ON THE BACK END. WINDS SHIFT TO A MORE WESTERLY DIRECTION THROUGH
THE LOW LEVELS AS COLD FRONT DROPS SOUTH AFTER MIDNIGHT. GFS
SHOWS A DROP IN PCP WATER DOWN TO 1.5 INCHES BY THIS EVENING. HRRR
SHOWS SHOWERS MOVING OFF TO THE NORTHEAST LEAVING ONLY ISOLATED
SHWRS OVER LOCAL AREA UNTIL COLD FRONT REACHES THE AREA LATER IN
THE NIGHT.
COLD FRONT WILL DROP SOUTH THROUGH TONIGHT WITH WINDS SHIFTING
AROUND FURTHER...BECOMING NORTH BEHIND FRONT. SHOULD SEE ANOTHER
POTENTIAL FOR INCREASED SHOWER ACTIVITY AS COLD FRONT MOVES
THROUGH AREA OVERNIGHT...ESPECIALLY BETWEEN 3 AM AND DAYBREAK.
COOLER AIR WILL MAKE ITS WAY IN BEHIND FRONT WHICH SHOULD BE RUNNING
WEST TO EAST ACROSS SOUTH CAROLINA BY MORNING. DEWPOINT TEMPS SHOULD
DROP BELOW 60 BY DAYBREAK OVER MOST OF AREA WHILE TEMPS WILL BE
MAKING THERE WAY DOWN THROUGH THE 60S.
&&
.SHORT TERM /WEDNESDAY THROUGH THURSDAY NIGHT/...
AS OF 330 AM TUESDAY...FORECAST REMAINS ONE OF LOWER CONFIDENCE AS A
MOISTURE LADEN SOUTHWEST FLOW CONTINUES AT THE MID LEVELS THROUGH
THE PERIOD. AT THE SURFACE A BACKDOOR FRONT WILL PUSH ACROSS THE
AREA DURING THE MORNING HOURS WEDNESDAY. SEVERAL WEAK SHORTWAVES
WILL MOVE THROUGH THE FLOW AND MODELS HAVE BEEN HAVING DIFFICULTY
WITH THE TIMING AND PLACEMENT OF THESE FEATURES. IT SEEMS TO
CHANGE DRAMATICALLY FROM CYCLE TO CYCLE. PRUDENCE CALLS FOR
KEEPING POPS IN THE FORECAST THROUGHOUT WITH AT LEAST SOME
VARIATION IN VALUES. THE LATEST BEST FORCING APPEARS TO OCCUR
THURSDAY AND I HAVE ELEVATED TO LIKELY IN SOME AREAS WITH HIGH
CHANCE ELSEWHERE. AIRMASS IN THE WAKE OF THE FRONT IS COOLER AND
HIGHS WILL BE CONFINED TO THE 60S BOTH DAYS AND OVERNIGHT LOWS IN
THE 50S SHOWING LITTLE DIURNAL RANGE.
&&
.LONG TERM /FRIDAY THROUGH TUESDAY/...
AS OF 330 AM TUESDAY...500MB PATTERN WILL FEATURE THE CLOSED LOW
ACROSS THE SOUTHWEST FINALLY GETTING KICKED OUT AND WEAKENING AS
IT MOVES TO THE EAST. IN FACT THE TROUGH WEAKENS SO MUCH A
SOUTHWEST FLOW WILL CONTINUE UNABATED THROUGH THE PERIOD. THIS
ALLOWS A BAROCLINIC ZONE TO REMAIN DRAPED ACROSS THE SOUTHEAST.
THIS SCENARIO IS BASED PRIMARILY ON THE GFS SOLUTIONS. THE ECMWF
PAINTS A DIFFERENT SCENARIO WITH THE LOW HOLDING BACK WITH THE
PERSISTENT WET SOUTHWEST PERSISTING. FOR THIS REASON I AM HOLDING
ON TO SLIGHT CHANCE POPS FOR SUNDAY WITH CHANCE EITHER SIDE OF
THIS. HIGHS WILL GENERALLY BE 75-80 DEGREES WITH LOWS IN THE LOWER
TO MIDDLE 60S.
&&
.AVIATION /18Z TUESDAY THROUGH SUNDAY/...
AS OF 18Z...STILL NOT VERY CONFIDENT ABOUT CONVECTION THIS
AFTERNOON. WILL LEAN ON THE HRRR MODEL THAT SHOWS A PRETTY DECENT
BAND OF CONVECTION SETTING UP BETWEEN FLO AND THE MYRTLES BY 20Z.
THIS ACTIVITY IS COURTESY OF LOW PRESSURE CENTERED WEST OF THE
REGION WITH SPOKES OF VORTICITY ROTATING EAST OF THE LOW. THE LAST
VORT WILL MOVE NORTHEAST AND OUT OF THE REGION LATE THIS
AFTERNOON...FOLLOWED BY CLEARING SKIES.
TONIGHT...STRATUS WILL AGAIN SET UP...WITH WINDS SHIFTING TO THE
NORTH LATE IN THE FORECAST PERIOD AS A BACK DOOR FRONT DROPS IN.
THERE WILL LIKELY BE SOME PRECIP ALONG AND BEHIND THE
FRONT...PROBABLY MORE DRIZZLE THAN RAIN.
EXTENDED OUTLOOK...PREDOMINATELY IFR CONDITIONS ARE EXPECTED WED
AFTERNOON THROUGH THURSDAY WITH A WEDGE. IMPROVING CONDITIONS FRI.
DETERIORATING CONDITIONS AGAIN SATURDAY AFTERNOON THROUGH SUNDAY
WITH A COLD FRONT.
&&
.MARINE...
NEAR TERM /THROUGH TONIGHT/...
AS OF 200 AM TUESDAY...SOUTH TO SW WINDS WILL CONTINUE THROUGH
MOST OF TONIGHT IN ADVANCE OF COLD FRONT DROPPING DOWN FROM THE
NORTH. AS THE FRONT DRAWS CLOSER...THE WINDS WILL PICK UP
SLIGHTLY AS THEY VEER FURTHER TO THE SOUTHWEST AND EVENTUALLY
AROUND TO THE NORTH BEHIND THE FRONT. LOOKS LIKE THE COLD FRONT
WILL RUN WEST TO EAST ACROSS SOUTH CAROLINA BISECTING LOCAL WATERS
BY DAYBREAK. WINDS WILL CONTINUE IN THE GENERAL 10 TO 15 KT
RANGE...WITH SEAS RANGING FROM 2 TO 4 FT MOST PLACES WITH A SLIGHT
RISE OVERNIGHT.
SHORT TERM /WEDNESDAY THROUGH THURSDAY NIGHT/...
AS OF 330 AM TUESDAY...A NORTHEAST FLOW WILL BE IN THE INITIAL
STAGES EARLY WEDNESDAY AS A WEDGE PATTERN DEVELOPS. SPEEDS INCREASE
FROM AROUND TEN KNOTS EARLY TO A RANGE OF 20-15 KNOTS BY LATE IN THE
EVENING. THEY REMAIN IN THIS RANGE UNTIL LATER THURSDAY AFTERNOON
WHEN THEY BEGIN THEIR STEADY DECLINE TO TEN KNOTS OR LESS BY FRIDAY
MORNING. WITH THE STRONGER WINDS...SEAS WILL WORK UP TO SMALL CRAFT
CRITERIA BY WEDNESDAY EVENING AND REMAIN SO UNTIL LATE THURSDAY
AFTERNOON.
LONG TERM /FRIDAY THROUGH SATURDAY/...
AS OF 330 AM TUESDAY...A RELATIVELY LIGHT FLOW IS EXPECTED FROM THE
EAST/SOUTHEAST FRIDAY ON THE ORDER OF 10-15 KNOTS. THE FLOW WILL
VEER TO SOUTHWEST SATURDAY AND PICK UP STEAM A BIT AS A COLD FRONT
MOVES CLOSER FROM THE WEST. NOT A LOT OF CONFIDENCE IN THIS FORECAST
HOWEVER AS MODELS HAVE BEEN STRUGGLING WITH THE FEATURES. SEAS WILL
BE 1-3 FEET.
&&
.ILM WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
NC...NONE.
MARINE...NONE.
&&
$$
NEAR TERM...RGZ
SHORT TERM...SHK
LONG TERM...SHK
AVIATION...DL
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
1130 AM EDT TUE APR 14 2015
.SYNOPSIS...
UNSETTLED CONDITIONS WILL PERSIST TODAY AS A SERIES OF WEAK
DISTURBANCES MOVE ACROSS. A COLD FRONT WILL CROSS THE AREA EARLY
WEDNESDAY MORNING...STALLING TO OUR SOUTH ON THURSDAY. LOW
PRESSURE MAY DEVELOP ALONG THE FRONT THURSDAY INTO FRIDAY..LIFTING
NORTH OF THE AREA SATURDAY. A COLD FRONT WILL MOVE ACROSS THE
CAROLINAS FROM THE WEST LATE SATURDAY. HIGH PRESSURE WILL BUILD IN
FROM THE WEST SUNDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 1030 AM TUESDAY...ENTRENCHED IN WARM AND MOIST AIR MASS
TODAY AS COLD FRONT MAKES ITS WAY SOUTH INTO NORTH CAROLINA.
DEWPOINTS IN THE MID 60S TODAY AND TEMPS IN THE MID 70S WITH
EXTENSIVE CLOUD COVER THIS MORNING...BUT SHOULD RISE A FEW MORE
DEGREES TO BRING TEMPS AROUND 80 MOST PLACES. MAY SEE SOME BRIEF
BREAKS IN CLOUDS THIS AFTERNOON WHICH WILL HELP PROPEL TEMPS UP A
LITTLE FURTHER. DEEP MOISTURE THROUGH THIS AFTERNOON WITH PCP
WATER VALUES UP CLOSE TO 2 INCHES AND SOUNDING PARAMETERS ALL
POINTING TO POTENTIAL FOR TSTMS. THE PRIMARY FOCUS WOULD BE
FURTHER NW INTO CENTRAL CAROLINAS AS WAVE OF LOW PRESSURE MOVES UP
THROUGH THE TENNESSEE VALLEY TOWARD THE NORTHEAST. A SHORTWAVE
MOVING THROUGH WILL ALSO HELP TO ENHANCE ANY CONVECTION THROUGH
THIS AFTERNOON.
FOR OUR LOCAL AREA...MODELS SHOW DRIER AIR MAKING ITS WAY UP INTO
THE AREA AS WINDS SHIFT TO A MORE SW-W THROUGH THIS AFTERNOON.
GFS SHOWS A DROP IN PCP WATER DOWN TO 1.5 INCHES BY THIS EVENING.
HRRR SHOWS SHOWERS AROUND THIS MORNING MOVING OFF TO THE NORTHEAST
LEAVING ONLY ISOLATED SHWRS OVER LOCAL AREA. IF SUN BREAKS OUT AT
ALL...IT WILL ACT TO DESTABILIZE THE ATMOSPHERE FURTHER AND COULD
PRODUCE SOME DIFFERENTIAL HEATING BUT OVERALL CLOUD COVER WILL
LIMIT SEA BREEZE STRENGTH THROUGH THIS AFTERNOON. POTENTIAL WILL
EXIST ESPECIALLY THROUGH THIS AFTERNOON TO SEE SOME ISOLATED
STRONGER STORMS. SPC HAS NORTHWEST PORTIONS OF FORECAST AREA IN
MARGINAL RISK WITH STRONGER WIND THREAT...BUT MAIN THREAT AREA
SHOULD REMAIN FARTHER TO THE NORTH AND WEST.
COLD FRONT WILL DROP SOUTH THROUGH TONIGHT WITH WINDS SHIFTING
AROUND FURTHER BECOMING NORTH BEHIND FRONT. SHOULD SEE ANOTHER
POTENTIAL FOR INCREASED SHOWER ACTIVITY AS COLD FRONT MOVES
THROUGH AREA OVERNIGHT. COOLER AIR WILL MAKE ITS WAY IN BEHIND
FRONT WHICH SHOULD BE SOUTH OF AREA BY MORNING. TEMPS MAY DROP
BELOW 60 BY DAYBREAK.
&&
.SHORT TERM /WEDNESDAY THROUGH THURSDAY NIGHT/...
AS OF 330 AM TUESDAY...FORECAST REMAINS ONE OF LOWER CONFIDENCE AS A
MOISTURE LADEN SOUTHWEST FLOW CONTINUES AT THE MID LEVELS THROUGH
THE PERIOD. AT THE SURFACE A BACKDOOR FRONT WILL PUSH ACROSS THE
AREA DURING THE MORNING HOURS WEDNESDAY. SEVERAL WEAK SHORTWAVES
WILL MOVE THROUGH THE FLOW AND MODELS HAVE BEEN HAVING DIFFICULTY
WITH THE TIMING AND PLACEMENT OF THESE FEATURES. IT SEEMS TO
CHANGE DRAMATICALLY FROM CYCLE TO CYCLE. PRUDENCE CALLS FOR
KEEPING POPS IN THE FORECAST THROUGHOUT WITH AT LEAST SOME
VARIATION IN VALUES. THE LATEST BEST FORCING APPEARS TO OCCUR
THURSDAY AND I HAVE ELEVATED TO LIKELY IN SOME AREAS WITH HIGH
CHANCE ELSEWHERE. AIRMASS IN THE WAKE OF THE FRONT IS COOLER AND
HIGHS WILL BE CONFINED TO THE 60S BOTH DAYS AND OVERNIGHT LOWS IN
THE 50S SHOWING LITTLE DIURNAL RANGE.
&&
.LONG TERM /FRIDAY THROUGH MONDAY/...
AS OF 330 AM TUESDAY...500MB PATTERN WILL FEATURE THE CLOSED LOW
ACROSS THE SOUTHWEST FINALLY GETTING KICKED OUT AND WEAKENING AS
IT MOVES TO THE EAST. IN FACT THE TROUGH WEAKENS SO MUCH A
SOUTHWEST FLOW WILL CONTINUE UNABATED THROUGH THE PERIOD. THIS
ALLOWS A BAROCLINIC ZONE TO REMAIN DRAPED ACROSS THE SOUTHEAST.
THIS SCENARIO IS BASED PRIMARILY ON THE GFS SOLUTIONS. THE ECMWF
PAINTS A DIFFERENT SCENARIO WITH THE LOW HOLDING BACK WITH THE
PERSISTENT WET SOUTHWEST PERSISTING. FOR THIS REASON I AM HOLDING
ON TO SLIGHT CHANCE POPS FOR SUNDAY WITH CHANCE EITHER SIDE OF
THIS. HIGHS WILL GENERALLY BE 75-80 DEGREES WITH LOWS IN THE LOWER
TO MIDDLE 60S.
&&
.AVIATION /14Z TUESDAY THROUGH SATURDAY/...
AS OF 12Z...QUITE A BIT OF UNCERTAINTY WITH RESPECT TO TIMING OF THE
CONVECTION TODAY...SAFE TO SAY THERE WILL BE A LOT OF
CONVECTION...ESPECIALLY NEAR THE COAST THIS MORNING. THE HRRR HAS A
REASONABLE HANDLE ON THINGS WITH CONVECTION NEAR THE COAST THIS
MORNING...FOLLOWED BY WIDESPREAD CONVECTION CWA WIDE THIS AFTERNOON.
ALL OF THIS ACTIVITY IS COURTESY OF LOW PRESSURE CENTERED WEST OF
THE REGION WITH SPOKES OF VORTICITY ROTATING EAST OF THE LOW. THE
LAST VORT WILL MOVE NORTHEAST AND OUT OF THE REGION LATE THIS
AFTERNOON...FOLLOWED BY CLEARING SKIES. TONIGHT...STRATUS WILL AGAIN
SET UP...WITH WINDS SHIFTING TO THE NORTH LATE IN THE FORECAST
PERIOD AS A BACK DOOR FRONT DROPS IN.
EXTENDED OUTLOOK...WED...A CHANCE OF MVFR IN THUNDERSTORMS.
MVFR/SHOWERS THURS THROUGH FRI. VFR SAT.
&&
.MARINE...
NEAR TERM /THROUGH TONIGHT/...
AS OF 1030 AM TUESDAY...SOUTH TO SW WINDS WILL CONTINUE TODAY
AND TONIGHT IN ADVANCE OF A SLOW MOVING COLD FRONT. WINDS WILL
CONTINUE IN THE GENERAL 10 TO 15 KT RANGE...WITH SEAS RANGING FROM
3 TO 5 FT MOST PLACES. HIGHEST PORTION OF THE SEA HEIGHT RANGE
WILL BE OVER OUR NC WATERS...WITH SEAS CLOSER TO 3 FT FURTHER
SOUTH.
SHORT TERM /WEDNESDAY THROUGH THURSDAY NIGHT/...
AS OF 330 AM TUESDAY...A NORTHEAST FLOW WILL BE IN THE INITIAL STAGES
EARLY WEDNESDAY AS A WEDGE PATTERN DEVELOPS. SPEEDS INCREASE FROM
AROUND TEN KNOTS EARLY TO A RANGE OF 20-15 KNOTS BY LATE IN THE
EVENING. THEY REMAIN IN THIS RANGE UNTIL LATER THURSDAY AFTERNOON WHEN
THEY BEGIN THEIR STEADY DECLINE TO TEN KNOTS OR LESS BY FRIDAY
MORNING. WITH THE STRONGER WINDS...SEAS WILL WORK UP TO SMALL
CRAFT CRITERIA BY WEDNESDAY EVENING AND REMAIN SO UNTIL LATE
THURSDAY AFTERNOON.
LONG TERM /FRIDAY THROUGH SATURDAY/...
AS OF 330 AM TUESDAY...A RELATIVELY LIGHT FLOW IS EXPECTED FROM THE
EAST/SOUTHEAST FRIDAY ON THE ORDER OF 10-15 KNOTS. THE FLOW WILL
VEER TO SOUTHWEST SATURDAY AND PICK UP STEAM A BIT AS A COLD FRONT
MOVES CLOSER FROM THE WEST. NOT A LOT OF CONFIDENCE IN THIS FORECAST
HOWEVER AS MODELS HAVE BEEN STRUGGLING WITH THE FEATURES. SEAS WILL
BE 1-3 FEET.
&&
.ILM WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
NC...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...
NEAR TERM...RGZ
SHORT TERM...SHK
LONG TERM...SHK
AVIATION...DL
MARINE...
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
643 AM EDT TUE APR 14 2015
.SYNOPSIS...
UNSETTLED CONDITIONS WILL PERSIST TODAY AS A SERIES OF WEAK
DISTURBANCES MOVE ACROSS. A COLD FRONT WILL CROSS THE AREA EARLY
WEDNESDAY MORNING...STALLING TO OUR SOUTH ON THURSDAY. LOW
PRESSURE MAY DEVELOP ALONG THE FRONT THURSDAY INTO FRIDAY..LIFTING
NORTH OF THE AREA SATURDAY. A COLD FRONT WILL MOVE ACROSS THE
CAROLINAS FROM THE WEST LATE SATURDAY. HIGH PRESSURE WILL BUILD IN
FROM THE WEST SUNDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 630 AM TUESDAY...NO CHANGES TO THE FORECAST WITH THE LATEST
UPDATE. PREVIOUS DISCUSSION FOLLOWS:
UNSEASONABLE WARMTH TODAY AND TONIGHT AS SOUTHERLY FLOW CONTINUES
IN ADVANCE OF A SLOW- MOVING COLD FRONT. EXTENSIVE CLOUDINESS AND
THE GOOD LIKELIHOOD OF SHOWERS WITH ISOLATED THUNDERSTORMS WILL
ALSO MARK THE NEAR TERM AS A DEEP MOISTURE-TAP OFF THE GULF OF
MEXICO AND SOUTH ATLANTIC CONTINUES. MODEL SOUNDINGS SHOW AMPLE
MOISTURE WITH P/W VALUES VARYING BETWEEN 1.5 AND 2.0 INCHES TODAY
AND TONIGHT...WITH DEWPOINTS WELL UP IN THE 60S DURING THE DAYTIME
AND EVENING HOURS.
AN APPROACHING UPPER DISTURBANCE WILL ENHANCE PRECIP CHANCES DURING
THE DAYLIGHT HOURS...BUT TIMING OF THIS FEATURE AMONGST VARIOUS
GUIDANCE IS VARIABLE AND MAKES IT HARD TO PIN DOWN WHEN THE BEST
CHANCES FOR CONVECTION TO OCCUR. FOR THE OVERNIGHT HOURS GUIDANCE IS
IN AGREEMENT ON A DRY SLOT MOVING THROUGH IN ASSOCIATION WITH THE
IMPENDING COLD FRONT. A CONSENSUS OF GUIDANCE HAS THE FRONT
BISECTING THE CWA FROM ROUGHLY EAST TO WEST BY DAYBREAK ON WEDNESDAY.
TEMPERATURES WILL BE WELL ABOVE NORMAL TODAY...WITH HIGHS IN THE
LOWER TO MID 80S AND LOWS IN THE 60S.
&&
.SHORT TERM /WEDNESDAY THROUGH THURSDAY NIGHT/...
AS OF 330 AM TUESDAY...FORECAST REMAINS ONE OF LOWER CONFIDENCE AS A
MOISTURE LADEN SOUTHWEST FLOW CONTINUES AT THE MID LEVELS THROUGH
THE PERIOD. AT THE SURFACE A BACKDOOR FRONT WILL PUSH ACROSS THE
AREA DURING THE MORNING HOURS WEDNESDAY. SEVERAL WEAK SHORTWAVES
WILL MOVE THROUGH THE FLOW AND MODELS HAVE BEEN HAVING DIFFICULTY
WITH THE TIMING AND PLACEMENT OF THESE FEATURES. IT SEEMS TO
CHANGE DRAMATICALLY FROM CYCLE TO CYCLE. PRUDENCE CALLS FOR
KEEPING POPS IN THE FORECAST THROUGHOUT WITH AT LEAST SOME
VARIATION IN VALUES. THE LATEST BEST FORCING APPEARS TO OCCUR
THURSDAY AND I HAVE ELEVATED TO LIKELY IN SOME AREAS WITH HIGH
CHANCE ELSEWHERE. AIRMASS IN THE WAKE OF THE FRONT IS COOLER AND
HIGHS WILL BE CONFINED TO THE 60S BOTH DAYS AND OVERNIGHT LOWS IN
THE 50S SHOWING LITTLE DIURNAL RANGE.
&&
.LONG TERM /FRIDAY THROUGH MONDAY/...
AS OF 330 AM TUESDAY...500MB PATTERN WILL FEATURE THE CLOSED LOW
ACROSS THE SOUTHWEST FINALLY GETTING KICKED OUT AND WEAKENING AS
IT MOVES TO THE EAST. IN FACT THE TROUGH WEAKENS SO MUCH A
SOUTHWEST FLOW WILL CONTINUE UNABATED THROUGH THE PERIOD. THIS
ALLOWS A BAROCLINIC ZONE TO REMAIN DRAPED ACROSS THE SOUTHEAST.
THIS SCENARIO IS BASED PRIMARILY ON THE GFS SOLUTIONS. THE ECMWF
PAINTS A DIFFERENT SCENARIO WITH THE LOW HOLDING BACK WITH THE
PERSISTENT WET SOUTHWEST PERSISTING. FOR THIS REASON I AM HOLDING
ON TO SLIGHT CHANCE POPS FOR SUNDAY WITH CHANCE EITHER SIDE OF
THIS. HIGHS WILL GENERALLY BE 75-80 DEGREES WITH LOWS IN THE LOWER
TO MIDDLE 60S.
&&
.AVIATION /12Z TUESDAY THROUGH SATURDAY/...
AS OF 12Z...QUITE A BIT OF UNCERTAINTY WITH RESPECT TO TIMING OF THE
CONVECTION TODAY...SAFE TO SAY THERE WILL BE A LOT OF
CONVECTION...ESPECIALLY NEAR THE COAST THIS MORNING. THE HRRR HAS A
REASONABLE HANDLE ON THINGS WITH CONVECTION NEAR THE COAST THIS
MORNING...FOLLOWED BY WIDESPREAD CONVECTION CWA WIDE THIS AFTERNOON.
ALL OF THIS ACTIVITY IS COURTESY OF LOW PRESSURE CENTERED WEST OF
THE REGION WITH SPOKES OF VORTICITY ROTATING EAST OF THE LOW. THE
LAST VORT WILL MOVE NORTHEAST AND OUT OF THE REGION LATE THIS
AFTERNOON...FOLLOWED BY CLEARING SKIES. TONIGHT...STRATUS WILL AGAIN
SET UP...WITH WINDS SHIFTING TO THE NORTH LATE IN THE FORECAST
PERIOD AS A BACK DOOR FRONT DROPS IN.
EXTENDED OUTLOOK...WED...A CHANCE OF MVFR IN THUNDERSTORMS.
MVFR/SHOWERS THURS THROUGH FRI. VFR SAT.
&&
.MARINE...
NEAR TERM /THROUGH TONIGHT/...
AS OF 630 AM TUESDAY...NO CHANGES TO THE FORECAST WITH THE LATEST
UPDATE. PREVIOUS DISCUSSION FOLLOWS:
SOUTH TO SW WINDS WILL CONTINUE TODAY AND TONIGHT IN ADVANCE OF A
SLOW MOVING COLD FRONT. WINDS WILL CONTINUE IN THE GENERAL 10 TO
15 KT RANGE...WITH SEAS RANGING FROM 3 TO 5 FT MOST PLACES.
HIGHEST PORTION OF THE SEA HEIGHT RANGE WILL BE OVER OUR NC
WATERS...WITH SEAS CLOSER TO 3 FT FURTHER SOUTH.
SHORT TERM /WEDNESDAY THROUGH THURSDAY NIGHT/...
AS OF 330 AM TUESDAY...A NORTHEAST FLOW WILL BE IN THE INITIAL STAGES
EARLY WEDNESDAY AS A WEDGE PATTERN DEVELOPS. SPEEDS INCREASE FROM
AROUND TEN KNOTS EARLY TO A RANGE OF 20-15 KNOTS BY LATE IN THE
EVENING. THEY REMAIN IN THIS RANGE UNTIL LATER THURSDAY AFTERNOON WHEN
THEY BEGIN THEIR STEADY DECLINE TO TEN KNOTS OR LESS BY FRIDAY
MORNING. WITH THE STRONGER WINDS...SEAS WILL WORK UP TO SMALL
CRAFT CRITERIA BY WEDNESDAY EVENING AND REMAIN SO UNTIL LATE
THURSDAY AFTERNOON.
LONG TERM /FRIDAY THROUGH SATURDAY/...
AS OF 330 AM TUESDAY...A RELATIVELY LIGHT FLOW IS EXPECTED FROM THE
EAST/SOUTHEAST FRIDAY ON THE ORDER OF 10-15 KNOTS. THE FLOW WILL
VEER TO SOUTHWEST SATURDAY AND PICK UP STEAM A BIT AS A COLD FRONT
MOVES CLOSER FROM THE WEST. NOT A LOT OF CONFIDENCE IN THIS FORECAST
HOWEVER AS MODELS HAVE BEEN STRUGGLING WITH THE FEATURES. SEAS WILL
BE 1-3 FEET.
&&
.ILM WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
NC...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...SHK
NEAR TERM...REK
SHORT TERM...SHK
LONG TERM...SHK
AVIATION...DL
MARINE...SHK
AREA FORECAST DISCUSSION
NWS NEWPORT/MOREHEAD CITY NC
619 AM EDT TUE APR 14 2015
.SYNOPSIS...
A COLD FRONT WILL APPROACH FROM THE NORTHWEST TODAY AND MOVE
OFFSHORE LATE TONIGHT. THE FRONT WILL THEN BECOME STATIONARY OVER
THE SOUTHEAST STATES FOR SEVERAL DAYS. ANOTHER COLD FRONT WILL
MOVE THROUGH FRIDAY NIGHT. HIGH PRESSURE WILL PASS TO THE NORTH
SUNDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
AS OF 615 AM TUESDAY...PRECIPITATION HAS BEEN VERY SLOW TO IMPACT
MOST OF OUR CWA WITH JUST A FEW LIGHT SHOWERS OR SPRINKLES ALONG
THE COAST THUS FAR. HEAVY RAINFALL LOOKS TO REMAIN OFFSHORE THIS
MORNING. LATEST 3KM HRRR HAS A DECENT HANDLE ON PRECIP PLACEMENT
AND SHOWS ACTIVITY RAMPING UP IN THE AFTERNOON. THE GFS/ECMWF DO
NOT SHOW THE PRONOUNCED DRY SLOT FROM EARLIER AND HAVE THUS UPPED
POPS BACK TO LIKELY STARTING AROUND NOON INTO LATE IN THE DAY.
HAVE GONE A FEW DEGREES BELOW GUIDANCE MAX TEMPERATURES TODAY
GIVEN THE CLOUD COVER AND PRECIPITATION...WITH HIGHS IN THE
MID/UPPER 70S INLAND AND UPPER 60S/LOWER 70S BEACHES. SPC HAS
PORTIONS OF THE AREA IN A MARGINAL THREAT FOR SEVERE WEATHER. MOST
OF THE INSTABILITY WILL BE OFFSHORE THIS MORNING...WITH MOST
INDICES INLAND THIS AFTERNOON...BUT GIVEN THE CLOUD
COVER/PRECIPITATION...DO NOT EXPECT MUCH OF A SEVERE THREAT TODAY.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 AM WEDNESDAY/...
AS OF 340 AM TUESDAY...DIFFICULT TO TIME VARIOUS WAVES OF LOW
PRESSURE AND MID-LEVEL ENERGY MOVING THROUGH THE FAST SOUTHWEST
FLOW ALOFT. THINK RAIN WILL INCREASE IN INTENSITY AND COVERAGE
AGAIN FROM THE EARLY EVENING THROUGH ABOUT MIDNIGHT...THEN
COVERAGE WANES A BIT OVERNIGHT. THIS IS INDICATED IN POPS GOING
FROM LIKELY EARLY TO HIGH CHANCE LATE TONIGHT. GOOD AGREEMENT IN
GUIDANCE SHOWING MINIMUM TEMPS TONIGHT UPPER 50S TO LOWER 60S.
COLD FRONT CROSSES THE AREA AND MOVES OFFSHORE BETWEEN ROUGHLY 06Z
AND 09Z...ENDING THE THREAT OF ANY ELEVATED CONVECTION.
&&
.LONG TERM /WEDNESDAY THROUGH MONDAY/...
AN ACTIVE SOUTHERN JET STREAM AND INFLOW OF DEEP GULF MOISTURE WILL
LEAD TO UNSETTLED WEATHER THRU MUCH OF THIS FORECAST PERIOD WITH
POSSIBLE LOCALLY HEAVY RAIN AT TIMES. HOWEVER CONFIDENCE VERY LOW IN
FORECAST SPECIFICS ESPECIALLY AT LONGER RANGES GIVEN POOR MODEL
AGREEMENT AND LACK OF RUN TO RUN MODEL CONSISTENCY.
WED AND WED NIGHT...POSSIBLY DRIER THIS PERIOD ESPECIALLY NORTHERN
TIER...HOWEVER MODELS ARE TRENDING A BIT WETTER S AND INLAND. HIGH
PRES WILL BUILD IN FROM THE N WED AND BEGIN TO SHIFT OFFSHORE WED
NIGHT. DRIER AIR WILL TRY TO SPREAD IN FROM THE N WED...HOWEVER
MOISTURE WILL LINGER S AND W AND WITH WEAK IMPULSES CROSSING ALOFT
WILL CONT TO HAVE THREAT OF PRECIP WITH CHANCE POPS TO SOUTH AND
SLIGHT CHANCE NORTH WED AND WED NIGHT. COOL HIGHS WED IN THE 60S
WITH 50S WED NIGHT.
THU THROUGH SUNDAY...MOISTURE WILL INCREASE AGAIN THU WITH SCT SHRA
DEVELOPING AS LOW PRES FORMS TO THE S. THE LOW WILL LINGER NEAR THE
CST THROUGH FRIDAY WITH CONT THREAT OF SHRA...AGAIN SIGNIFICANT
MODELS DIFFERENCES SO MAINTAINED FORECAST CONTINUITY FOR NOW. A COLD
FRONT WILL APPROACH FRI NIGHT AND CROSS LATE SAT OR SAT NIGHT WITH
SCT SHRA. CONTINUED ISOLD TSRA FRI AFTERNOON AND AGAIN SAT AS WEAK
INSTABILITY DEVELOPS OVER REGION. LONGER RANGE MODELS NOW TRYING TO
PUSH DEEP MOISTURE BACK INTO THE FORECAST AREA ON SUNDAY BUT WILL
KEEP JUST SLIGHT CHANCE POPS AWAITING BETTER MODEL CONSISTENCY.
HIGHS ONLY IN THE 60S IN COOL NE FLOW THURSDAY THEN WARMING INTO THE
70S/NEAR SEASONAL NORMS THRU THE REST OF THE PERIOD...AS USUAL FOR
THIS TIME OF YEAR BEACHES WILL BE A BIT COOLER. LOWS 50S TO LOWER
60S.
MODELS BEGINNING TO TREND DRIER MONDAY AS DEEPER MOISTURE SHIFTS
OFFSHORE BUT WILL CONTINUE WITH LOW CHANCE POPS AHEAD OF POSSIBLE
COLD FRONTAL PASSAGE. HIGHS IN THE LOWER/MID 70S INLAND TO 60S
CST.
&&
.AVIATION /10Z TUESDAY THROUGH SATURDAY/...
SHORT TERM /THROUGH 12Z WEDNESDAY/...
AS OF 630 AM TUESDAY...DIFFICULT AVIATION FORECAST IN TERM OF
TIMING WAVES OF PRECIPITATION AND LOWER CLOUDS. ALL TAF SITES
CURRENTLY AT MVFR AND WILL NOW KEEP THEM IN THAT RANGE THROUGH
MOST OF THE DAY AS STEADIER RAINFALL ARRIVES BY THE AFTERNOON.
CEILINGS GO UP A BIT AROUND 00Z...BUT ALL GUIDANCE SHOWS
WIDESPREAD IFR BEHIND COLD FRONT AS NORTHEAST WINDS DEVELOP WITH
PLENTIFUL LOW-LEVEL MOISTURE.
LONG TERM /WEDNESDAY THROUGH SATURDAY/...
REDUCED FLIGHT CATEGORIES MAY CONTINUE EARLY WED BEFORE DRIER AIR
WORKS IN AND SHOULD SLOWLY SEE LOW CLOUDS SCOUR OUT HOWEVER SRN TIER
MAY HOLD ON TO SOME SUB VFR CONDITIONS. SCT SHRA EXPECTED TO DEVELOP
THU AND CONT INTO FRI WITH PERIODS OF SUB VFR LIKELY FROM TIME TO
TIME. COLD FRONT WILL APPROACH SAT WITH AGAIN SCT SHRA/POSS TSRA AND
BRIEF PERIODS OF SUB VFR EXPECTED.
&&
.MARINE...
SHORT TERM /TODAY AND TONIGHT/...
AS OF 620 AM TUESDAY...SE/S WINDS ACROSS THE COASTAL WATERS AT 10
KNOTS OR LESS...EXCEPT SOME GUSTS INTO THE MID/UPPER TEENS AT
DIAMOND BUOY. SEAS RUNNING 3 TO 4 FEET WITH 5 FEET AT DIAMOND. NO
BIG CHANGES TO THE CURRENT MARINE FORECAST AS WINDS BECOME MORE
SOUTHWEST AND INCREASE TO A SOLID 15 TO 20 KNOTS OVER THE
CENTRAL WATERS LATER TODAY AND TONIGHT AS LOCAL NWPS/SWAN BUILDS
SEAS TO 3 TO 5 FEET OVER ALL COASTAL WATERS...ESPECIALLY BEHIND
THE FRONT EARLY WEDNESDAY MORNING.
LONG TERM /WEDNESDAY THROUGH SATURDAY/...
NNE WINDS WILL INCREASE TO 20 TO 25 KTS WED AS HIGH BUILDS IN FROM
THE N... SCA LIKELY LATER TUE NIGHT THROUGH WED AS SEAS BUILD TO 5
TO 8 FT. THE HIGH WILL SLIDE OFFSHORE THU WITH WEAK LOW DEVELOPING
TO THE S...WINDS WILL BECOME EAST AND CONT GUSTY MAINLY 15 TO 25 KTS
WITH SEAS REMAINING ELEVATED AT 6 TO 9 FT. LOW PRES MOVES UP THE
COAST FRIDAY. MODELS DIFFER ON TRACK AND INTENSITY BUT A CONCENSUS
FORECAST WOULD SUGGEST THE LOW MOVING NE OFF THE NC COAST WITH SLOW
DEEPENING. THIS SOLUTION WOULD MAINTAIN MODERATE E/NE WINDS AND ONLY
SLOWLY SUBSIDING SEAS THRU THE END OF THE WEEK. WINDS BECOME NW
BEHIND THE EXITING LOW FRIDAY NIGHT AND SATURDAY WITH CONTINUED
SLOWLY FALLING SEA HEIGHTS TO BELOW SMALL CRAFT ADVISORY LEVELS.
&&
.MHX WATCHES/WARNINGS/ADVISORIES...
NC...NONE.
MARINE...SMALL CRAFT ADVISORY FROM 10 AM WEDNESDAY TO 9 AM EDT SATURDAY
FOR AMZ150-152-154.
&&
$$
SYNOPSIS...CTC
NEAR TERM...CTC
SHORT TERM...CTC
LONG TERM...BTC
AVIATION...BTC/CTC
MARINE...BTC/CTC
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
120 AM EDT TUE APR 14 2015
.SYNOPSIS...
A COASTAL TROUGH JUST OFF THE COAST WILL LIFT NORTHWARD OVERNIGHT.
A COLD FRONT WILL CROSS THE AREA EARLY WEDNESDAY MORNING...STALLING
TO OUR SOUTH ON THURSDAY. LOW PRESSURE MAY DEVELOP ALONG THE FRONT
THURSDAY INTO FRIDAY..LIFTING NORTH OF THE AREA SATURDAY. A COLD
FRONT WILL MOVE ACROSS THE CAROLINAS FROM THE WEST LATE SATURDAY.
HIGH PRESSURE WILL BUILD IN FROM THE WEST SUNDAY.
&&
.NEAR TERM /UNTIL 6 AM THIS MORNING/...
AS OF 130 AM TUESDAY...NO CHANGES TO THE FORECAST WITH THE LATEST
UPDATE. PREVIOUS DISCUSSION FOLLOWS:
SHOWERS HAVE BECOME QUITE FRAGMENTED ACROSS THE AREA...HOWEVER
THE ENVIRONMENT REMAINS CONDUCIVE FOR NEW SHOWERS TO DEVELOP AT
ALMOST ANY TIME...ESPECIALLY ACROSS THE CAPE FEAR AREA. FOR
WILMINGTON THE STRONGEST MAGNITUDE OF WARM ADVECTION SHOULD BE
OCCURRING IN THE NEXT FEW HOURS. SMALL BUT POSITIVE CONVECTIVE
INSTABILITY IS STILL PRESENT AS WELL...WITH KLTX RADAR SHOWING NEW
CELLS DEVELOPING VERY NEAR THE RADAR SITE IN BRUNSWICK COUNTY OVER
THE PAST HALF HOUR.
IT IS TOUGH TO SAY WHICH MODEL IS PERFORMING WELL. THE HRRR IS
MAINTAINING A VERY DRY FORECAST OVERNIGHT...BUT RADAR SUMMARIES
PLUS THE OVERALL SYNOPTIC SITUATION ARGUE OTHERWISE. I WILL
MAINTAIN FAIRLY HIGH POPS (60-70 PERCENT) IN THE WILMINGTON METRO
AREA...WITH LOWER POPS (30-50 PERCENT) ELSEWHERE FOR THE OVERNIGHT
PERIOD. NO CHANGES TO TEMPERATURES. DISCUSSION FROM 730 PM
FOLLOWS...
RADAR IMAGERY SHOWS A CLUSTER OF SHOWERS ASSOCIATED WITH SE
INFLOW OFF THE ATLANTIC ACROSS THE MYRTLE BEACH AREA...SPREADING
NORTH- NORTHWESTWARD. MODELS SUGGEST THESE SHOWERS ARE BEING
SUSTAINED BY TWO FACTORS: WEAK LIFT RESULTING FROM A SURGE OF WARM
ADVECTION BELOW 800 MB...COUPLED WITH AROUND 100 J/KG OF
CONVECTIVE INSTABILITY. A LESS ORGANIZED AREA OF SHOWERS ACROSS
CENTRAL SOUTH CAROLINA APPROACHING DARLINGTON AND FLORENCE
COUNTIES IS ROOTED HIGHER UP IN THE ATMOSPHERE WHERE WIND FLOW IS
SOUTHWESTERLY. THESE ARE MAINLY THE RESULT OF WEAK ISENTROPIC LIFT
ALONG THE 305K THETA SURFACE WHICH SHOULD ABATE BY MIDNIGHT.
MODELS ARE IN PRETTY GREAT DISAGREEMENT ABOUT PRECIPITATION
COVERAGE AND INTENSITY OVERNIGHT. THE 18Z NAM PROBABLY HAS THE
BEST HANDLE ON PRECIPITATION TRIGGERS I CAN ANALYZE. I ALSO LIKE
HOW THE 18Z NAM SEEMS TO BE ONE OF THE FEW MODELS TO SEE THAT
SURFACE WINDS ARE NOT VEERING WILDLY AROUND TO THE SE AT THE
COAST. (THE 22Z RAP PROBABLY HAS THE BEST HANDLE ON WINDS
CURRENTLY)
MY IDEA...BASED PRIMARILY ON THE NAM AND THE PREVIOUS FORECASTER`S
WORK...IS THAT THE BAND OF SUBSTANTIAL SHOWER ACTIVITY NEAR MYRTLE
BEACH WILL HAVE LIMITED SUCCESS WORKING INLAND...AND WILL INSTEAD
PREFERENTIALLY SHIFT NORTHWARD ALONG THE COAST AFFECTING
WILMINGTON AND THE CAPE FEAR AREA AFTER MIDNIGHT. THE ACTIVITY
ACROSS CENTRAL SC WILL MOVE NORTHEASTWARD DROPPING SPOTTIER
RAINFALL...AND DIMINISHING IN COVERAGE BY MIDNIGHT AS LIFT ALONG
THE 305K AND 310K ISENTROPIC SURFACES DIMINISHES.
PLENTY OF CLOUDS AND DEWPOINTS RISING INTO THE 60S WILL HOLD LOWS
IN THE MID 60S FOR MOST LOCATIONS...VIRTUALLY UNCHANGED FROM THE
PREVIOUS FORECAST.
&&
.SHORT TERM /6 AM THIS MORNING THROUGH WEDNESDAY NIGHT/...
AS OF 3 PM MONDAY... FORECAST SOUNDINGS SHOW A DEEP LAYER OF
SATURATION FOR MUCH OF TUESDAY. AND WHILE THE ENTIRE DAY WILL NOT BE
A WASHOUT IT IS QUITE DIFFICULT TO HAVE ANY GIVEN HOUR WITH LOW POPS
DUE TO SEVERAL SMALL SCALE PERTURBATIONS MOVING THROUGH THE FLOW.
GIVEN WIDESPREAD CLOUD COVER MODELS HAVING DIFFICULTY DISCERNING HOW
MUCH INSTABILITY DEVELOPS. REGARDLESS THERE WILL BE ENOUGH FOR
ISOLATED THUNDER BUT BREAKS OR SUFFICIENT THINNING IN CLOUDS COULD
LEAD TO ENOUGH INSTABILITY SUCH THAT SPC HAS REFERENCED NC IN SWODY2.
CHANCE FOR ACTUAL SEVERE WEATHER TOO LOW FOR EVEN A `MARGINAL`
ISOPLETH IN THE OUTLOOK. GIVEN RELATIVELY LOW LCLS/MEAGER LAPSE
RATES FAVORING FAIRLY THIN BUT TALL CAPE AND THE LACK OF ANY DRY
AIR THE MAIN `THREAT` WILL BE NON-SEVERE (20-40MPH) WET
DOWNBURSTS. THE GFS DOES SHOW SOME DRYING AND THE DEVELOPMENT OF
DCAPE BY 00Z DUE TO THE EXIT OF DAY`S STRONGEST SHORTWAVE BUT MUCH
PAST PEAK HEATING THERE MAY NOT BE SUFFICIENT LIFT REMAINING FOR
DEEP CONVECTION. COLD FRONT PUSHES THROUGH DURING THE LATTER HALF
OF TUESDAY NIGHT ENDING MOST IF NOT ALL OF THE LIGHTNING AS LOW
LEVELS STRONGLY STABILIZE UNDERNEATH INVERSION AND LIFT REMAINS
TOO WEAK TO TAP ELEVATED INSTABILITY, IF ANY. LIGHT STRATIFORM
RAIN THEN STAYS IN THE FORECAST FOR MUCH OF WEDNESDAY AS THE
SURFACE WEDGE CONTINUES TO EXPERIENCE WEAK OVERRUNNING. HIGH TEMPS
FROM TUESDAY TO WEDNESDAY WILL GO FROM ROUGHLY 5 DEGREES ABOVE
CLIMO TO ROUGHLY 5 DEGREES BELOW. GIVEN THE STRENGTH OF THE WEDGE
WOULD NOT BE SURPRISED IF WEDNESDAY HIGHS NEED TO BE LOWERED A FEW
DEGREES.
&&
.LONG TERM /THURSDAY THROUGH MONDAY/...
AS OF 3 PM MONDAY...MID LEVEL RIDGING OVER THE WESTERN ATLANTIC AND
GULF OF MEXICO ALONG WITH 5H TROUGHING/CUTOFF OVER THE SOUTHWEST
CONUS WILL SPREAD DEEP MOISTURE OVER THE SOUTHEAST INTO THE START OF
NEXT WEEK. IN ADDITION TO THE DEEP MOISTURE THE SOUTHWEST FLOW ALOFT
WILL ENSURE A STEADY SERIES OF SHORTWAVES EJECTING FROM THE 5H
CUTOFF PASS OVER THE REGION. THESE WAVES MAY WORK TO ENHANCE DIURNAL
CONVECTION...DEPENDING ON THEIR TIMING. TIMING THESE FEATURES IN THE
EXTENDED IS DIFFICULT AT BEST AND GIVEN THE UNCERTAINTY WITH RESPECT
TO AVAILABLE DIURNAL INSTABILITY AS WELL AS THE LOCATION OF ANY
LINGERING CONVECTIVE BOUNDARIES DO NOT PLAN ON ANY MAJOR CHANGES TO
POP FORECAST AT THIS TIME.
TEMPERATURES THU WILL BE NEAR TO BELOW CLIMO WITH HIGH PRESSURE
RIDGING DOWN THE COAST FROM THE NORTHEAST. THE PARENT HIGH MOVES OFF
THE NEW ENGLAND COAST BY FRI...BREAKING THE RIDGE AND ALLOWING
PASSAGE OF WEAK WARM FRONT/COASTAL TROUGH. THIS WILL USHER IN A
PERIOD OF HIGHS AND LOWS ABOVE TO WELL ABOVE CLIMO BUT IS ALSO
LIKELY TO KEEP PRECIP CHANCES ELEVATED THROUGH THE WEEKEND. CUTOFF
EMERGING FROM THE SOUTHWEST THIS WEEKEND WILL HELP DRAG A COLD FRONT
ACROSS THE AREA LATE IN THE PERIOD. STILL SOME UNCERTAINTY WITH
RESPECT TO TIMING BUT GFS IS A BIT FASTER...SUN NIGHT...WHILE THE
ECMWF IS SLOWER...LATER MON.
&&
.AVIATION /00Z TUESDAY THROUGH SATURDAY/...
AS OF 06Z...ALL IN ALL...EXPECT DETERIORATING CONDITIONS ALL
TERMINALS TONIGHT WITH MVFR OR EVEN IFR CONDITIONS AT ALL
SITES...MAINLY DUE TO CIGS. ADDITIONALLY...SHOWERS ARE POSSIBLE
MUCH OF THE NIGHT...ESPECIALLY ALONG THE COAST. AFTER DAYBREAK
CONDITIONS SHOULD IMPROVE TO MVFR OR EVEN VFR ON S TO SW WINDS INVOF
10 KT BUT SHRA AND TSRA ARE POSSIBLE ALL TERMINALS FOR MUCH OF THE
DAY WITH MVFR OR TEMPO IFR POSSIBLE.
EXTENDED OUTLOOK...WED...A CHANCE OF MVFR IN THUNDERSTORMS.
MVFR/SHOWERS THURS THROUGH FRI. VFR SAT.
&&
.MARINE...
NEAR TERM /THROUGH TONIGHT/...
AS OF 130 AM TUESDAY...NO CHANGES TO THE FORECAST WITH THE LATEST
UPDATE. PREVIOUS DISCUSSION FOLLOWS:
WIND SPEEDS NEARSHORE HAVE DIMINISHED OVER THE PAST FEW HOURS
WHILE WINDS OFFSHORE CONTINUE TO BLOW 15-20 KT ACCORDING TO THE
FRYING PAN SHOALS AND OFFSHORE WRIGHTSVILLE BEACH (41037) BUOYS.
THE COASTAL TROUGH IS TOUGH TO LOCATE BUT IS PROBABLY 5-10 MILES
OFFSHORE...AND SHOULD PUSH ACROSS OUR ENTIRE MARINE AREA IN THE
NEXT 3-5 HOURS. THIS WILL ALLOW WIND DIRECTIONS TO VEER EAST-
SOUTHEASTERLY ALL THE WAY UP TO THE BEACHES.
SHOWERS HAVE DIMINISHED OVERALL BUT THE ENVIRONMENT REMAINS
SUPPORTIVE OF NEW SHOWERS TO DEVELOP AT ANY TIME...MAINLY NORTH OF
MYRTLE BEACH ACROSS THE CAPE FEAR AREA WATERS. I AM MAINTAINING
HIGH CHANCES FOR SHOWERS IN THE FORECAST HERE. DISCUSSION FROM 730
PM FOLLOWS...
A COASTAL TROUGH IS HELPING TO KEEP WIND DIRECTIONS BACKED AROUND
TO THE EAST AND NORTHEAST ALONG THE COAST...WHILE FARTHER OFFSHORE
AT THE FRYING PAN SHOALS BUOY AND THE EDISTO BUOY WINDS HAVE
ALREADY SWUNG AROUND TO THE SOUTHEAST. THIS BOUNDARY SHOULD LIFT
NORTHWARD ALMOST LIKE A WEAK WARM FRONT TONIGHT...ALLOWING WINDS
EVEN AT THE BEACHES TO ASSUME A MORE SOUTHERLY DIRECTION BY
DAYBREAK TUESDAY.
AN AREA OF SUBSTANTIAL SHOWER ACTIVITY NEAR MYRTLE BEACH SHOULD
GRADUALLY LIFT NORTH ALONG THE COAST TONIGHT...REACHING CAPE FEAR
BY MIDNIGHT. SEAS CURRENTLY 3-5 FEET SHOULD MAINTAIN THEMSELVES
WITH A STEADY ONSHORE WIND EXPECTED TO CONTINUE.
SHORT TERM /TUESDAY THROUGH WEDNESDAY NIGHT/...
AS OF 3 PM MONDAY... SOUTH TO SOUTHWESTERLY FLOW ON TUESDAY IN A
PREFRONTAL FLOW REGIME AS BOUNDARY APPROACHES FROM THE NORTHWEST.
NEITHER WINDS NOR SEAS WILL BE PARTICULARLY STIRRED UP SO THE MAIN
THREAT TO MARINERS WILL BE THE FACT THAT SOME SHOWERS AND STORMS
COULD PRODUCE HEAVY ENOUGH RAINFALL FOR SOME VISIBILITY
RESTRICTIONS IN ADDITION TO SOME FAIRLY GUSTY (30-40KT) WINDS.
LATE NIGHT FROPA MAY CHANGE THAT HOWEVER AS A WEDGE OF HIGH
PRESSURE STARTS GETTING ESTABLISHED OVER LAND. AS THIS FEATURE
STRENGTHENS IN PART DUE TO RAIN FALLING INTO IT THE GRADIENT AND
RESULTING WIND/SEAS WILL RISE. AN ADVISORY WILL BE HOISTED AT SOME
POINT THOUGH ACTUAL ADVISORY CONDITIONS/6FT SEAS LIKELY NOT
MATERIALIZING TIL NIGHTTIME.
LONG TERM /THURSDAY THROUGH SATURDAY/...
AS OF 3 PM MONDAY...PINCHED GRADIENT BETWEEN HIGH RIDGING IN FROM
THE NORTH AND COASTAL TROUGH WILL MAINTAIN NORTHEAST FLOW IN THE
20 TO 25 KT RANGE THU AND THU NIGHT. EXTENDED PERIOD OF INCREASED
NORTHEAST FLOW WILL KEEP SEAS OVER 6 FT ACROSS MUCH OF THE WATERS
AND HEADLINES ARE LIKELY TO BE CARRIED OVER FROM THE SHORT TERM
PERIOD. GRADIENT WEAKENS FRI AS THE HIGH SHIFTS EAST AS TROUGH
MOVES ONSHORE/LIFTS NORTH. AS THIS OCCURS WINDS WILL SHIFT FROM
NORTHEAST THU NIGHT TO EAST LATER FRI WITH SOUTHWEST FLOW
DEVELOPING LAT FRI NIGHT AND CONTINUING ON SAT. WEAKER GRADIENT
FRI AND SAT WILL KEEP SPEEDS GENERALLY 10 KT OR LESS WITH SEAS
DECREASING FROM 3 TO 5 FT FRI MORNING TO 2 TO 3 FT SAT AFTERNOON.
&&
.ILM WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
NC...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...MBB
NEAR TERM...REK/TRA
SHORT TERM...MBB
LONG TERM...III
AVIATION...RAN
MARINE...REK/TRA/MBB
AREA FORECAST DISCUSSION
NWS NEWPORT/MOREHEAD CITY NC
1253 AM EDT TUE APR 14 2015
.SYNOPSIS...
A COLD FRONT WILL APPROACH FROM THE NORTHWEST TUESDAY AND MOVE
THROUGH EASTERN NC TUESDAY EVENING. THE FRONT WILL THEN BECOME
STATIONARY OVER THE SOUTHEAST STATES FOR SEVERAL DAYS. ANOTHER
COLD FRONT WILL MOVE THROUGH FRIDAY NIGHT. HIGH PRESSURE WILL PASS
TO THE NORTH SUNDAY.
&&
.NEAR TERM /UNTIL 6 AM THIS MORNING/...
AS OF 1245 AM TUESDAY...STILL ONLY SPOTTY RAIN ACROSS THE
REGION...BUT LATEST RADAR SHOWS INCREASING COVERAGE SOUTHEAST OF
WILMINGTON. LATEST 3KM HRRR SPREAD MORE PRECIPITATION INTO THE
COASTAL COUNTIES AFTER ABOUT 09Z OR 10Z. ADJUSTED POPS JUST A
BIT...BUT STILL FEEL LIKELY POPS ARE A GOOD BET BY THE EARLY
MORNING HOURS. ADJUSTED TEMPERATURES AND DEWPOINTS UP A BIT NEAR
THE COAST BASED ON LATEST OBSERVATIONS.
&&
.SHORT TERM /6 AM THIS MORNING THROUGH 6 PM WEDNESDAY/...
AS OF 3 PM MON...DEEP MOISTURE IN PLACE ALONG WITH LIFT PROVIDED
BY THE APPROACHING COLD FRONT WILL RESULT IN NUMEROUS SHOWERS.
CONTINUED LIKELY POPS WITH THUNDER POSSIBLE IN THE AFTERNOON.
GUIDANCE TEMPS LOOK TOO HIGH DUE TO SHOWERS AND OVERCAST SKIES.
HIGHS WILL RANGE IN THE LOWER TO MID 70S.
&&
.LONG TERM /WEDNESDAY NIGHT THROUGH TUESDAY/...
AS OF 230 PM MON...UNSETTLED THRU MUCH OF THIS PD WITH POSS OF
LOCALLY HEAVY RAIN HOWEVER CONFIDENCE QUITE LOW GIVEN POOR MODEL
AGREEMENT.
TUE NIGHT...COLD FRONT WILL SAG S THRU THE REGION WITH GOOD
COVERAGE OF SHRA EXPECTED...WILL CONT LIKELY POPS ALL AREAS IN
THE EVENING THEN CST LATE. MODELS A BIT WARMER THIS RUN AND
RAISED TEMPS TO MID 50S N AND AROUND 60 S.
WED AND WED NIGHT...A BIT DRIER THIS PERIOD ESPECIALLY NORTHERN
TIER...HOWEVER MODELS ARE TRENDING A BIT WETTER S AND INLAND.
HIGH PRES WILL BUILD IN FROM THE N WED AND BEGIN TO SHIFT OFFSHORE
WED NIGHT. DRIER AIR WILL TRY TO SPREAD IN FROM THE N
WED...HOWEVER MOISTURE WILL LINGER S AND W AND WITH WEAK IMPULSES
CROSSING A LOFT WILL CONT TO HAVE THREAT OF PRECIP. INCREASED POPS
TO CHC S AND SLIGHT CHC N WED AND WED NIGHT. HIGHS WED WILL BE IN
THE 60S WITH 50S WED NIGHT.
THU THROUGH THE SUNDAY...MOISTURE WILL INCREASE AGAIN THU WITH SCT
SHRA DEVELOPING AS LOW PRES FORMS TO THE S. THE LOW WILL LINGER
NEAR THE CST THROUGH FRIDAY WITH CONT THREAT OF SHRA...AGAIN
SIGNIFICANT MODELS DIFF SO LEANED TOWARD WPC SOLUTION THRU THIS
PERIOD WITH CHC POPS. A COLD FRONT WILL APPROACH FRI NIGHT AND
CROSS LATE SAT OR SAT NIGHT SCT SHRA. CONTINUED ISOLD TSRA FRI
AFTERNOON AND AGAIN SAT AS WEAK INSTABILITY DEVELOPS OVER REGION.
SHOULD FINALLY DRY OUT SUNDAY AS FRONT PUSHES WELL OFFSHORE.
HIGHS LOWER 70S INLAND THU THEN WARMING WELL INTO THE 70S REST OF
THE PERIOD..AS USUAL FOR THIS TIME OF YEAR BEACHES WILL BE A BIT
COOLER. LOWS 50S TO LOWER 60S.
MONDAY...DEEPER MOISTURE WILL RETURN AS HIGH SLIDES OFFSHORE AND
LOW PRESSURE APPROACHES FROM THE SW. HAVE CHC POPS WITH HIGHS IN
THE LOWER 70S INLAND TO 60S CST.
&&
.AVIATION /06Z TUESDAY THROUGH SATURDAY/...
SHORT TERM /THROUGH 06Z WEDNESDAY/...
AS OF 1250 AM TUESDAY...VFR CONDITIONS HOLDING TOUGH AS
PRECIPITATION SLOWLY MOVING INTO OUR REGION WITH ATMOSPHERE SLOWLY
BECOMING MORE SATURATED. EXPECT MVFR CEILINGS TO DEVELOP IN THE
NEXT FEW HOURS GIVEN UPSTREAM OBSERVATIONS. SOUTHEAST WINDS WILL
VEER SOUTH TONIGHT THEN BECOME SOUTHWEST TUESDAY.
LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/...
AS OF 230 PM MON...REDUCED FLIGHT CATEGORIES WILL CONTINUE TUE
NIGHT ESPECIALLY AFTER COLD FRONT SAGS S WITH GOOD INVERSION
DEVELOPING. DRIER AIR WORKS IN WED AND SHOULD SLOWLY SEE LOW
CLOUDS SCOUR OUT HOWEVER SRN TIER MAY HOLD ON TO SOME SUB VFR
CONDITIONS. SCT SHRA EXPECTED TO DEVELOP THU AND CONT INTO FRI
WITH PERIODS OF SUB VFR LIKELY FROM TIME TO TIME. COLD FRONT WILL
APPROACH SAT WITH AGAIN SCT SHRA/POSS TSRA AND BRIEF PERIODS OF
SUB VFR EXPECTED.
&&
.MARINE...
SHORT TERM /THROUGH TUESDAY/
AS OF 1255 AM TUESDAY...LITTLE CHANGE TO CURRENT MARINE FORECAST.
WINDS CURRENTLY SOUTHEAST AT 10 KNOTS...EXCEPT AROUND 15 KNOTS
OVER THE CENTRAL WATERS. SEAS ARE GENERALLY 2 TO 4 FEET IN ALL
AREAS...WITH PERHAPS A FEW 5 FOOTS OVER THE OUTER EDGES OF THE
CENTRAL WATERS. WINDS BECOMING MORE SOUTHERLY AT 10 TO 15 KNOTS ON
TUESDAY WITH SEAS 3 TO 5 FEET.
LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/... AS OF 230 PM
MON...S TO SW WINDS 10 TO 20 KTS TUE EVENING WILL GRAD SHIFT TO N
LATE AS COLD FRONT CROSSES. NNE WINDS WILL INCREASE TO 20 TO 25
KTS WED AS HIGH BUILDS IN FROM THE N... SCA LIKELY LATER TUE NIGHT
THROUGH WED AS SEAS BUILD TO 5 TO 8 FT. THE HIGH WILL SLIDE
OFFSHORE THU WITH WEAK LOW DEVELOPING TO THE S...WINDS WILL BECOME
EAST AND CONT GUSTY MAINLY 15 TO 25 KTS WITH SEAS REMAINING
ELEVATED AT 5 TO 9 FT. WEAK LOW WILL LINGER S OF REGION FRI WITH
SSE WINDS 10 TO 15 KT AND SEAS SUBSIDING TO 4 TO 6 FEET...HIGHEST
OUTER CENTRAL/SRN WATERS. COLD FRONT WILL APPROACH FROM THE W
LATER FRI NIGHT AND SAT WITH LIGHT WINDS FRI NIGHT BECOMING SSW
WINDS 10 TO 20 KTS SAT AHEAD OF THE FRONT..SEAS MAINLY 3 TO 5 FT
SAT.
&&
.MHX WATCHES/WARNINGS/ADVISORIES...
NC...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...HSA
NEAR TERM...CTC
SHORT TERM...HSA
LONG TERM...RF
AVIATION...RF/CTC/DAG
MARINE...RF/CTC
AREA FORECAST DISCUSSION
NWS BISMARCK ND
923 PM CDT WED APR 15 2015
.UPDATE...
ISSUED AT 923 PM CDT WED APR 15 2015
RADAR ECHOS ACROSS THE FAR SOUTHWEST...OTHERWISE DRY SO ONCE AGAIN
SCALED BACK ON POPS FOR THIS UPDATE. OTHER EDITS MINOR.
UPDATE
ISSUED AT 808 PM CDT WED APR 15 2015
WILL ALLOW THE RED FLAG TO EXPIRE AS SCHEDULED WITH WINDS TAPERING
OFF AND RH VALUES QUICKLY INCREASING.
UPDATE
ISSUED AT 720 PM CDT WED APR 15 2015
SCALED BACK ON POPS A BIT WITH A VOID OF ANY SORT OF DECENT RADAR
RETURNS ACROSS NORTH DAKOTA. ALLOWED THE WIND ADVISORY TO EXPIRE
AS WE ARE NOW BELOW ADVISORY CRITERIA EAST...AND WITH WINDS
EXPECTED TO QUICKLY TAPER OFF FURTHER OVER THE NEXT HOUR OR SO.
STRONG UPPER LEVEL LOW PRESSURE CONTINUES TO SPIN JUST WEST OF THE
CENTRAL ROCKIES. ENERGY ROTATING AROUND THE LOW WILL SPIRAL NORTH
ACROSS THE WESTERN DAKOTAS AND SHOULD BRING SOME LIGHT RAIN. BAND
OF ENHANCED RADAR RETURNS CURRENTLY LIFTING NORTH ACROSS WESTERN
SOUTH DAKOTA TOWARDS MY SOUTHWEST. WITH T/TD SPREADS
20-30F...WILL KEEP POPS BELOW LIKELY FOR NOW AND CONTINUE TO
MONITOR.
RED FLAG WARNING WILL BE ALLOWED TO EXPIRE AT 01Z...ROUGHLY 45-50
MINUTES FROM NOW...AS WINDS TAPER OFF AND RH VALUES INCREASE.
&&
.SHORT TERM...(THIS EVENING THROUGH THURSDAY)
ISSUED AT 251 PM CDT WED APR 15 2015
FIRE WEATHER CONCERNS HIGHLIGHT THE SHORT TERM TONIGHT BUT WILL
DIMINISH TOMORROW. A COLD FRONT ACROSS WESTERN NORTH DAKOTA HAS
BEEN SLOWER TO MOVE EAST THAN EARLIER FORECAST. THE RESULT HAS
BEEN AN EXTENDED PERIOD OF GUSTY SOUTHERLY WINDS ACROSS CENTRAL
AND EASTERN NORTH DAKOTA UP THROUGH THIS AFTERNOON. THIS HAS
RESULTED AN MULTIPLE FIRES ACROSS CENTRAL NORTH DAKOTA. IMPROVING
CONDITIONS WILL FINALLY ARRIVE THIS EVENING AS THE FRONTAL
BOUNDARY MOVES TO CENTRAL NORTH DAKOTA THEN TO THE EAST AFTER
MIDNIGHT. THIS WILL BRING AN END TO THE STRONG SOUTHERLY WINDS.
CLOUDS ARE BEING DRAWN UP THROUGH EASTERN SOUTH DAKOTA WITH SOME
LIMITED LOW LEVEL MOISTURE. THE HRRR DOES GENERATE SOME LIGHT
PRECIP ACROSS THE EAST...BUT GENERALLY EAST OF THE JAMES RIVER
VALLEY THOUGH.
MEASURABLE PRECIPITATION WILL BE MOST LIKELY ACROSS THE SOUTHWEST
TONIGHT. BUT KEPT THE POPS LESS THAN 40 PERCENT.
ON THURSDAY...COOLER TEMPERATURES WITH HIGHS 60 TO 65.
.LONG TERM...(THURSDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 251 PM CDT WED APR 15 2015
A WEAK COLD FRONTAL BOUNDARY SHIFTING THROUGH NORTHERN NORTH DAKOTA
LATE THURSDAY NIGHT WILL UNDERGO FRONTOLYSIS AS IT SAGS SOUTH INTO
CENTRAL NORTH DAKOTA FRIDAY MORNING. SPLIT FLOW REMAINS OVER NORTH
DAKOTA FRIDAY WITH THE NORTHERN STREAM JUST GRAZING FAR NORTHERN
NORTH DAKOTA/TURTLE MOUNTAINS. A CLOSED LOW OVER COLORADO SLOWLY
EMERGES INTO THE CENTRAL PLAINS...WITH NORTH DAKOTA CAUGHT BETWEEN
THESE TWO STREAMS FRIDAY AND WILL MOSTLY REMAIN IN A LULL FRIDAY
WITH BENIGN WEATHER. FOR SATURDAY AND SATURDAY NIGHT...MODEL DATA
CONTINUES TO SUGGEST SOME INTERACTION WITH THE CLOSED LOW AND ITS
ASSOCIATED MOISTURE SPINNING INTO SOUTHERN NORTH DAKOTA...AND A
STRONG SHORTWAVE TROUGH/SURFACE COLD FRONT VIA THE NORTHERN STREAM
AS IT APPROACHES WESTERN NORTH DAKOTA 00Z SUNDAY. VARYING SOLUTIONS
AS TO THE TIMING AND AREAL COVERAGE OF PRECIPITATION THAT IS
FORECAST TO PUSH INTO NORTH DAKOTA SATURDAY AFTERNOON INTO SATURDAY
NIGHT. THE GFS REPRESENTS THE FASTEST AND MOST WIDESPREAD
PRECIPITATION SOLUTIONS...WITH CHANCES OF RAIN CROSSING THE SOUTHERN
BORDER BEFORE 12Z SATURDAY. THE GEM/ECMWF REPRESENT SLOWER SOLUTIONS
AND ARE MORE IN LINE WITH RAIN SHOWERS MAINLY CONFINED TO THE JAMES
RIVER VALLEY AND PORTIONS OF SOUTH CENTRAL NORTH DAKOTA LATE
SATURDAY AFTERNOON THROUGH SUNDAY MORNING. A COLD THERMAL
TROUGH/POCKET IS FORECAST TO FOLLOW SUNDAY NIGHT THROUGH MOST OF
NEXT WEEK. GOOD AGREEMENT BETWEEN THE GFS AND ECMWF WITH THIS IDEA.
850MB TEMPS ARE FORECAST TO RANGE BETWEEN -2C TO -8C THROUGH
THURSDAY. THIS WILL TRANSLATE TO AFTERNOON HIGH TEMPERATURES IN THE
UPPER 40S TO MID 50S.
CONCERNING FIRE WEATHER IN THE LONG TERM PERIOD...NOT ANTICIPATING
ANY FIRE WEATHER CONCERNS FRIDAY OR SATURDAY. DESPITE A COOLING
TREND SUNDAY ONWARD...STRONG WINDS AT TIMES WILL ALIGN WITH LOW
RELATIVE HUMIDITIES ACROSS PORTIONS OF WESTERN AND CENTRAL NORTH
DAKOTA AND WILL NEED TO MONITOR. STRONG NORTHWEST WINDS DEVELOPING
BEHIND A COLD FRONT ACROSS WESTERN AND CENTRAL NORTH DAKOTA SUNDAY
MAY WARRANT A WIND ADVISORY. IN ADDITION MINIMUM RELATIVE HUMIDITIES
OF AROUND 25 PERCENT IN THE SOUTHWEST MAY ALSO WARRANT A FIRE
WEATHER HEADLINE SUNDAY. THEN ON MONDAY THE STRONGEST WINDS AND
LOWEST RELATIVE HUMIDITIES ARE ALIGNED IN SOUTH CENTRAL NORTH
DAKOTA...THUS THIS REPRESENTS ANOTHER POTENTIAL FOR FIRE WEATHER
HEADLINES. WEAKER WINDS ARE EXPECTED FOR TUESDAY AND WEDNESDAY WITH
EVEN COOLER TEMPERATURES...WITH WIDESPREAD HIGHS IN THE 40S
WEDNESDAY. NO SIGNIFICANT SYSTEMS/PRECIPITATION EVENTS SUNDAY
THROUGH WEDNESDAY.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z THURSDAY EVENING)
ISSUED AT 720 PM CDT WED APR 15 2015
A COLD FRONT WAS SLOWLY PROPAGATING THROUGH THE WESTERN PART OF THE
STATE. STRONG SOUTHERLY WINDS WILL REMAIN THE GREATEST FORECAST
CONCERN AHEAD OF THIS FRONT AS IT CONTINUES TO DRIFT EAST. THE
STRONGEST WINDS WILL GUST UP TO 35-40 KNOTS AT KJMS THROUGH THE
AFTERNOON...WITH WINDS CALMING TO THE WEST. BEHIND THE
BOUNDARY...WINDS WILL SHIFT FROM THE NORTHWEST THROUGH THE NIGHT.
THERE WILL BE A SLIGHT CHANCE FOR LIGHT RAIN AT KDIK/KISN
TONIGHT...THEN FOR OTHER TERMINALS EARLY THURSDAY MORNING. VFR
CIGS/VSBYS ARE EXPECTED THROUGHOUT THE PERIOD.
&&
.FIRE WEATHER...
ISSUED AT 808 PM CDT WED APR 15 2015
RED FLAG WARNING ALLOWED TO EXPIRE WITH COOLING TEMPERATURES AND
RISING RELATIVE HUMIDITY. ON THURSDAY MINIMUM RELATIVE HUMIDITY
WILL FALL INTO THE UPPER TEENS NORTHWEST. HOWEVER THE WINDS WILL
BE MUCH LOWER.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...NH
SHORT TERM...WAA
LONG TERM...KS
AVIATION...NH
FIRE WEATHER...NH
AREA FORECAST DISCUSSION
NWS BISMARCK ND
808 PM CDT WED APR 15 2015
.UPDATE...
ISSUED AT 808 PM CDT WED APR 15 2015
WILL ALLOW THE RED FLAG TO EXPIRE AS SCHEDULED WITH WINDS TAPERING
OFF AND RH VALUES QUICKLY INCREASING.
UPDATE
ISSUED AT 720 PM CDT WED APR 15 2015
SCALED BACK ON POPS A BIT WITH A VOID OF ANY SORT OF DECENT RADAR
RETURNS ACROSS NORTH DAKOTA. ALLOWED THE WIND ADVISORY TO EXPIRE
AS WE ARE NOW BELOW ADVISORY CRITERIA EAST...AND WITH WINDS
EXPECTED TO QUICKLY TAPER OFF FURTHER OVER THE NEXT HOUR OR SO.
STRONG UPPER LEVEL LOW PRESSURE CONTINUES TO SPIN JUST WEST OF THE
CENTRAL ROCKIES. ENERGY ROTATING AROUND THE LOW WILL SPIRAL NORTH
ACROSS THE WESTERN DAKOTAS AND SHOULD BRING SOME LIGHT RAIN. BAND
OF ENHANCED RADAR RETURNS CURRENTLY LIFTING NORTH ACROSS WESTERN
SOUTH DAKOTA TOWARDS MY SOUTHWEST. WITH T/TD SPREADS
20-30F...WILL KEEP POPS BELOW LIKELY FOR NOW AND CONTINUE TO
MONITOR.
RED FLAG WARNING WILL BE ALLOWED TO EXPIRE AT 01Z...ROUGHLY 45-50
MINUTES FROM NOW...AS WINDS TAPER OFF AND RH VALUES INCREASE.
&&
.SHORT TERM...(THIS EVENING THROUGH THURSDAY)
ISSUED AT 251 PM CDT WED APR 15 2015
FIRE WEATHER CONCERNS HIGHLIGHT THE SHORT TERM TONIGHT BUT WILL
DIMINISH TOMORROW. A COLD FRONT ACROSS WESTERN NORTH DAKOTA HAS
BEEN SLOWER TO MOVE EAST THAN EARLIER FORECAST. THE RESULT HAS
BEEN AN EXTENDED PERIOD OF GUSTY SOUTHERLY WINDS ACROSS CENTRAL
AND EASTERN NORTH DAKOTA UP THROUGH THIS AFTERNOON. THIS HAS
RESULTED AN MULTIPLE FIRES ACROSS CENTRAL NORTH DAKOTA. IMPROVING
CONDITIONS WILL FINALLY ARRIVE THIS EVENING AS THE FRONTAL
BOUNDARY MOVES TO CENTRAL NORTH DAKOTA THEN TO THE EAST AFTER
MIDNIGHT. THIS WILL BRING AN END TO THE STRONG SOUTHERLY WINDS.
CLOUDS ARE BEING DRAWN UP THROUGH EASTERN SOUTH DAKOTA WITH SOME
LIMITED LOW LEVEL MOISTURE. THE HRRR DOES GENERATE SOME LIGHT
PRECIP ACROSS THE EAST...BUT GENERALLY EAST OF THE JAMES RIVER
VALLEY THOUGH.
MEASURABLE PRECIPITATION WILL BE MOST LIKELY ACROSS THE SOUTHWEST
TONIGHT. BUT KEPT THE POPS LESS THAN 40 PERCENT.
ON THURSDAY...COOLER TEMPERATURES WITH HIGHS 60 TO 65.
.LONG TERM...(THURSDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 251 PM CDT WED APR 15 2015
A WEAK COLD FRONTAL BOUNDARY SHIFTING THROUGH NORTHERN NORTH DAKOTA
LATE THURSDAY NIGHT WILL UNDERGO FRONTOLYSIS AS IT SAGS SOUTH INTO
CENTRAL NORTH DAKOTA FRIDAY MORNING. SPLIT FLOW REMAINS OVER NORTH
DAKOTA FRIDAY WITH THE NORTHERN STREAM JUST GRAZING FAR NORTHERN
NORTH DAKOTA/TURTLE MOUNTAINS. A CLOSED LOW OVER COLORADO SLOWLY
EMERGES INTO THE CENTRAL PLAINS...WITH NORTH DAKOTA CAUGHT BETWEEN
THESE TWO STREAMS FRIDAY AND WILL MOSTLY REMAIN IN A LULL FRIDAY
WITH BENIGN WEATHER. FOR SATURDAY AND SATURDAY NIGHT...MODEL DATA
CONTINUES TO SUGGEST SOME INTERACTION WITH THE CLOSED LOW AND ITS
ASSOCIATED MOISTURE SPINNING INTO SOUTHERN NORTH DAKOTA...AND A
STRONG SHORTWAVE TROUGH/SURFACE COLD FRONT VIA THE NORTHERN STREAM
AS IT APPROACHES WESTERN NORTH DAKOTA 00Z SUNDAY. VARYING SOLUTIONS
AS TO THE TIMING AND AREAL COVERAGE OF PRECIPITATION THAT IS
FORECAST TO PUSH INTO NORTH DAKOTA SATURDAY AFTERNOON INTO SATURDAY
NIGHT. THE GFS REPRESENTS THE FASTEST AND MOST WIDESPREAD
PRECIPITATION SOLUTIONS...WITH CHANCES OF RAIN CROSSING THE SOUTHERN
BORDER BEFORE 12Z SATURDAY. THE GEM/ECMWF REPRESENT SLOWER SOLUTIONS
AND ARE MORE IN LINE WITH RAIN SHOWERS MAINLY CONFINED TO THE JAMES
RIVER VALLEY AND PORTIONS OF SOUTH CENTRAL NORTH DAKOTA LATE
SATURDAY AFTERNOON THROUGH SUNDAY MORNING. A COLD THERMAL
TROUGH/POCKET IS FORECAST TO FOLLOW SUNDAY NIGHT THROUGH MOST OF
NEXT WEEK. GOOD AGREEMENT BETWEEN THE GFS AND ECMWF WITH THIS IDEA.
850MB TEMPS ARE FORECAST TO RANGE BETWEEN -2C TO -8C THROUGH
THURSDAY. THIS WILL TRANSLATE TO AFTERNOON HIGH TEMPERATURES IN THE
UPPER 40S TO MID 50S.
CONCERNING FIRE WEATHER IN THE LONG TERM PERIOD...NOT ANTICIPATING
ANY FIRE WEATHER CONCERNS FRIDAY OR SATURDAY. DESPITE A COOLING
TREND SUNDAY ONWARD...STRONG WINDS AT TIMES WILL ALIGN WITH LOW
RELATIVE HUMIDITIES ACROSS PORTIONS OF WESTERN AND CENTRAL NORTH
DAKOTA AND WILL NEED TO MONITOR. STRONG NORTHWEST WINDS DEVELOPING
BEHIND A COLD FRONT ACROSS WESTERN AND CENTRAL NORTH DAKOTA SUNDAY
MAY WARRANT A WIND ADVISORY. IN ADDITION MINIMUM RELATIVE HUMIDITIES
OF AROUND 25 PERCENT IN THE SOUTHWEST MAY ALSO WARRANT A FIRE
WEATHER HEADLINE SUNDAY. THEN ON MONDAY THE STRONGEST WINDS AND
LOWEST RELATIVE HUMIDITIES ARE ALIGNED IN SOUTH CENTRAL NORTH
DAKOTA...THUS THIS REPRESENTS ANOTHER POTENTIAL FOR FIRE WEATHER
HEADLINES. WEAKER WINDS ARE EXPECTED FOR TUESDAY AND WEDNESDAY WITH
EVEN COOLER TEMPERATURES...WITH WIDESPREAD HIGHS IN THE 40S
WEDNESDAY. NO SIGNIFICANT SYSTEMS/PRECIPITATION EVENTS SUNDAY
THROUGH WEDNESDAY.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z THURSDAY EVENING)
ISSUED AT 720 PM CDT WED APR 15 2015
A COLD FRONT WAS SLOWLY PROPAGATING THROUGH THE WESTERN PART OF THE
STATE. STRONG SOUTHERLY WINDS WILL REMAIN THE GREATEST FORECAST
CONCERN AHEAD OF THIS FRONT AS IT CONTINUES TO DRIFT EAST. THE
STRONGEST WINDS WILL GUST UP TO 35-40 KNOTS AT KJMS THROUGH THE
AFTERNOON...WITH WINDS CALMING TO THE WEST. BEHIND THE
BOUNDARY...WINDS WILL SHIFT FROM THE NORTHWEST THROUGH THE NIGHT.
THERE WILL BE A SLIGHT CHANCE FOR LIGHT RAIN AT KDIK/KISN
TONIGHT...THEN FOR OTHER TERMINALS EARLY THURSDAY MORNING. VFR
CIGS/VSBYS ARE EXPECTED THROUGHOUT THE PERIOD.
&&
.FIRE WEATHER...
ISSUED AT 808 PM CDT WED APR 15 2015
RED FLAG WARNING ALLOWED TO EXPIRE WITH COOLING TEMPERATURES AND
RISING RELATIVE HUMIDITY. ON THURSDAY MINIMUM RELATIVE HUMIDITY
WILL FALL INTO THE UPPER TEENS NORTHWEST. HOWEVER THE WINDS WILL
BE MUCH LOWER.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...NH
SHORT TERM...WAA
LONG TERM...KS
AVIATION...NH
FIRE WEATHER...NH
AREA FORECAST DISCUSSION
NWS BISMARCK ND
720 PM CDT WED APR 15 2015
.UPDATE...
ISSUED AT 720 PM CDT WED APR 15 2015
SCALED BACK ON POPS A BIT WITH A VOID OF ANY SORT OF DECENT RADAR
RETURNS ACROSS NORTH DAKOTA. ALLOWED THE WIND ADVISORY TO EXPIRE
AS WE ARE NOW BELOW ADVISORY CRITERIA EAST...AND WITH WINDS
EXPECTED TO QUICKLY TAPER OFF FURTHER OVER THE NEXT HOUR OR SO.
STRONG UPPER LEVEL LOW PRESSURE CONTINUES TO SPIN JUST WEST OF THE
CENTRAL ROCKIES. ENERGY ROTATING AROUND THE LOW WILL SPIRAL NORTH
ACROSS THE WESTERN DAKOTAS AND SHOULD BRING SOME LIGHT RAIN. BAND
OF ENHANCED RADAR RETURNS CURRENTLY LIFTING NORTH ACROSS WESTERN
SOUTH DAKOTA TOWARDS MY SOUTHWEST. WITH T/TD SPREADS
20-30F...WILL KEEP POPS BELOW LIKELY FOR NOW AND CONTINUE TO
MONITOR.
RED FLAG WARNING WILL BE ALLOWED TO EXPIRE AT 01Z...ROUGHLY 45-50
MINUTES FROM NOW...AS WINDS TAPER OFF AND TH VALUES INCREASE.
&&
.SHORT TERM...(THIS EVENING THROUGH THURSDAY)
ISSUED AT 251 PM CDT WED APR 15 2015
FIRE WEATHER CONCERNS HIGHLIGHT THE SHORT TERM TONIGHT BUT WILL
DIMINISH TOMORROW. A COLD FRONT ACROSS WESTERN NORTH DAKOTA HAS
BEEN SLOWER TO MOVE EAST THAN EARLIER FORECAST. THE RESULT HAS
BEEN AN EXTENDED PERIOD OF GUSTY SOUTHERLY WINDS ACROSS CENTRAL
AND EASTERN NORTH DAKOTA UP THROUGH THIS AFTERNOON. THIS HAS
RESULTED AN MULTIPLE FIRES ACROSS CENTRAL NORTH DAKOTA. IMPROVING
CONDITIONS WILL FINALLY ARRIVE THIS EVENING AS THE FRONTAL
BOUNDARY MOVES TO CENTRAL NORTH DAKOTA THEN TO THE EAST AFTER
MIDNIGHT. THIS WILL BRING AN END TO THE STRONG SOUTHERLY WINDS.
CLOUDS ARE BEING DRAWN UP THROUGH EASTERN SOUTH DAKOTA WITH SOME
LIMITED LOW LEVEL MOISTURE. THE HRRR DOES GENERATE SOME LIGHT
PRECIP ACROSS THE EAST...BUT GENERALLY EAST OF THE JAMES RIVER
VALLEY THOUGH.
MEASURABLE PRECIPITATION WILL BE MOST LIKELY ACROSS THE SOUTHWEST
TONIGHT. BUT KEPT THE POPS LESS THAN 40 PERCENT.
ON THURSDAY...COOLER TEMPERATURES WITH HIGHS 60 TO 65.
.LONG TERM...(THURSDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 251 PM CDT WED APR 15 2015
A WEAK COLD FRONTAL BOUNDARY SHIFTING THROUGH NORTHERN NORTH DAKOTA
LATE THURSDAY NIGHT WILL UNDERGO FRONTOLYSIS AS IT SAGS SOUTH INTO
CENTRAL NORTH DAKOTA FRIDAY MORNING. SPLIT FLOW REMAINS OVER NORTH
DAKOTA FRIDAY WITH THE NORTHERN STREAM JUST GRAZING FAR NORTHERN
NORTH DAKOTA/TURTLE MOUNTAINS. A CLOSED LOW OVER COLORADO SLOWLY
EMERGES INTO THE CENTRAL PLAINS...WITH NORTH DAKOTA CAUGHT BETWEEN
THESE TWO STREAMS FRIDAY AND WILL MOSTLY REMAIN IN A LULL FRIDAY
WITH BENIGN WEATHER. FOR SATURDAY AND SATURDAY NIGHT...MODEL DATA
CONTINUES TO SUGGEST SOME INTERACTION WITH THE CLOSED LOW AND ITS
ASSOCIATED MOISTURE SPINNING INTO SOUTHERN NORTH DAKOTA...AND A
STRONG SHORTWAVE TROUGH/SURFACE COLD FRONT VIA THE NORTHERN STREAM
AS IT APPROACHES WESTERN NORTH DAKOTA 00Z SUNDAY. VARYING SOLUTIONS
AS TO THE TIMING AND AREAL COVERAGE OF PRECIPITATION THAT IS
FORECAST TO PUSH INTO NORTH DAKOTA SATURDAY AFTERNOON INTO SATURDAY
NIGHT. THE GFS REPRESENTS THE FASTEST AND MOST WIDESPREAD
PRECIPITATION SOLUTIONS...WITH CHANCES OF RAIN CROSSING THE SOUTHERN
BORDER BEFORE 12Z SATURDAY. THE GEM/ECMWF REPRESENT SLOWER SOLUTIONS
AND ARE MORE IN LINE WITH RAIN SHOWERS MAINLY CONFINED TO THE JAMES
RIVER VALLEY AND PORTIONS OF SOUTH CENTRAL NORTH DAKOTA LATE
SATURDAY AFTERNOON THROUGH SUNDAY MORNING. A COLD THERMAL
TROUGH/POCKET IS FORECAST TO FOLLOW SUNDAY NIGHT THROUGH MOST OF
NEXT WEEK. GOOD AGREEMENT BETWEEN THE GFS AND ECMWF WITH THIS IDEA.
850MB TEMPS ARE FORECAST TO RANGE BETWEEN -2C TO -8C THROUGH
THURSDAY. THIS WILL TRANSLATE TO AFTERNOON HIGH TEMPERATURES IN THE
UPPER 40S TO MID 50S.
CONCERNING FIRE WEATHER IN THE LONG TERM PERIOD...NOT ANTICIPATING
ANY FIRE WEATHER CONCERNS FRIDAY OR SATURDAY. DESPITE A COOLING
TREND SUNDAY ONWARD...STRONG WINDS AT TIMES WILL ALIGN WITH LOW
RELATIVE HUMIDITIES ACROSS PORTIONS OF WESTERN AND CENTRAL NORTH
DAKOTA AND WILL NEED TO MONITOR. STRONG NORTHWEST WINDS DEVELOPING
BEHIND A COLD FRONT ACROSS WESTERN AND CENTRAL NORTH DAKOTA SUNDAY
MAY WARRANT A WIND ADVISORY. IN ADDITION MINIMUM RELATIVE HUMIDITIES
OF AROUND 25 PERCENT IN THE SOUTHWEST MAY ALSO WARRANT A FIRE
WEATHER HEADLINE SUNDAY. THEN ON MONDAY THE STRONGEST WINDS AND
LOWEST RELATIVE HUMIDITIES ARE ALIGNED IN SOUTH CENTRAL NORTH
DAKOTA...THUS THIS REPRESENTS ANOTHER POTENTIAL FOR FIRE WEATHER
HEADLINES. WEAKER WINDS ARE EXPECTED FOR TUESDAY AND WEDNESDAY WITH
EVEN COOLER TEMPERATURES...WITH WIDESPREAD HIGHS IN THE 40S
WEDNESDAY. NO SIGNIFICANT SYSTEMS/PRECIPITATION EVENTS SUNDAY
THROUGH WEDNESDAY.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z THURSDAY EVENING)
ISSUED AT 720 PM CDT WED APR 15 2015
A COLD FRONT WAS SLOWLY PROPAGATING THROUGH THE WESTERN PART OF THE
STATE. STRONG SOUTHERLY WINDS WILL REMAIN THE GREATEST FORECAST
CONCERN AHEAD OF THIS FRONT AS IT CONTINUES TO DRIFT EAST. THE
STRONGEST WINDS WILL GUST UP TO 35-40 KNOTS AT KJMS THROUGH THE
AFTERNOON...WITH WINDS CALMING TO THE WEST. BEHIND THE
BOUNDARY...WINDS WILL SHIFT FROM THE NORTHWEST THROUGH THE NIGHT.
THERE WILL BE A SLIGHT CHANCE FOR LIGHT RAIN AT KDIK/KISN
TONIGHT...THEN FOR OTHER TERMINALS EARLY THURSDAY MORNING. VFR
CIGS/VSBYS ARE EXPECTED THROUGHOUT THE PERIOD.
&&
.FIRE WEATHER...
ISSUED AT 251 PM CDT WED APR 15 2015
RED FLAG WARNING REMAINS IN EFFECT UNTIL 8 PM CDT. WITH THE
ADVANCING COLD FRONT THE STRONG SOUTHERLY WINDS WILL SUBSIDE THIS
EVENING. AFTER 8 PM CDT COOLER TEMPERATURES...RISING RELATIVE
HUMIDITY SHOULD END THE RED FLAG CONDITIONS. ON THURSDAY MINIMUM
RELATIVE HUMIDITY WILL FALL INTO THE UPPER TEENS NORTHWEST.
HOWEVER THE WINDS WILL BE MUCH LOWER. ALTHOUGH THE FIRE DANGER
WILL BE ELEVATED CRITICAL FIRE WEATHER WILL NOT BE REACHED.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
RED FLAG WARNING UNTIL 8 PM CDT /7 PM MDT/ THIS EVENING FOR
NDZ003>005-011>013-019>023-025-034>037-042-045>048-050-051.
&&
$$
UPDATE...NH
SHORT TERM...WAA
LONG TERM...KS
AVIATION...NH
FIRE WEATHER...WAA
AREA FORECAST DISCUSSION
NWS CHARLESTON WV
552 PM EDT TUE APR 14 2015
.SYNOPSIS...
HIGH PRESSURE TRACKS NORTH OF THE AREA LATE TONIGHT INTO WEDNESDAY.
LOW PRESSURE TRACKS SOUTH OF THE AREA THURSDAY...AND ANOTHER ON
SATURDAY. A COLD FRONT MAY ARRIVE SATURDAY NIGHT.
&&
.NEAR TERM /THROUGH WEDNESDAY/...
6 PM UPDATE...REMOVED THUNDER FROM SOUTHERN ZONES. ALSO...UPDATED
THE DEW POINTS...AS MUCH DRIER AIR IS MOVING INTO NORTHERN ZONES
QUICKER THAN FORECAST. OTHERWISE...NO CHANGES WERE NECESSARY.
PREVIOUS DISCUSSION FOLLOWS...
LOOKING AT A DECREASE IN COVERAGE OF THE SHOWERS THROUGH THE
REMAINDER OF THIS AFTERNOON AND EVENING AS THE SURFACE LOW FINALLY
PASSES TO THROUGH THE SOUTHERN ZONES AND TOWARDS THE MID ATLANTIC
COAST. AS WE DRY OUT FROM THE RAINFALL LAST NIGHT AND TODAY...WE
WILL NOT BE ABLE TO USHER IN A DRY AIRMASS FOR THE ENTIRETY OF
THE CWA...WITH LOW LEVEL MOISTURE LINGERING IN THE COAL FIELDS
AND SOUTHERN MOUNTAINS. HIGH PRESSURE WILL BUILD IN FOR THE
NORTHERN ZONES...BUT AN INVERTED SURFACE TROUGH WILL ASSIST WITH
THE LOW LEVEL MOISTURE RETENTION. WILL ALSO KEEP LOW END POPS IN
THESE AREAS AS WELL. NO THUNDER EXPECTED THROUGH THE FORECAST.
FOLLOWED THE HRRR FOR THE DEVELOPMENT OF THE POPS THROUGH 00Z
WEDNESDAY. NORTHWESTERN ZONES WILL SEE SOME CLEARING TONIGHT.
IN THE UPPER LEVELS...GETTING A BRIEF REPRIEVE WITH MODEST RIDGING
TONIGHT INTO WEDNESDAY BEFORE THE NEXT ROUND OF EMBEDDED VORTICITY
MAXIMA IN THE 500MB FLOW ARRIVES IN THE TUG FORK VALLEY.
NORTHERN HALF OF THE CWA WILL LIKELY BE WARMER THAN THE SOUTHERN
HALF GIVEN THE CLEARER CONDITIONS ON WEDNESDAY.
&&
.SHORT TERM /WEDNESDAY NIGHT THROUGH FRIDAY/...
MODELS HAVE A MEAN UPPER TROUGH CONTINUING OVER THE WEST CENTRAL
PORTION OF THE NATION...WITH RATHER WEAK SOUTHWEST FLOW ALOFT
EXTENDING ACROSS THE OHIO AND TENNESSEE VALLEYS. THERE WILL BE WEAK
UPPER IMPULSES IN THIS SOUTHWEST FLOW ALOFT...BUT IT APPEARS MOST
MODELS FOCUS ON ONE THAT COMES ACROSS THURSDAY INTO THURSDAY NIGHT.
ALTHOUGH HIGH PRESSURE CENTERED OVER THE MID ATLANTIC STATES WILL BE
THE DOMINANT FEATURE AT THE SURFACE...THIS UPPER FEATURE APPEARS TO
HAVE ENOUGH DYNAMICS AND MOISTURE TO SQUEEZE OUT A HIGH POP AND LOW
QPF FORECAST THURSDAY AND EARLY THURSDAY NIGHT. OTHERWISE...HAVE TO
KEEP AT LEAST SLIGHT POPS IN MOST OF THE PERIOD...GIVEN THE
UNCERTAINTY OF OTHER IMPULSES ALOFT. THERE WILL BE LOTS OF CLOUDS
OUTSIDE OF ANY SHOWERS...ESPECIALLY THURSDAY...BUT LITTLE THUNDER
WITH MARGINAL MODEL INSTABILITY AT BEST. TEMPERATURES WILL BE
MODERATE WITH HIGHS THURSDAY IN THE MID 60S UNDER CLOUDS AND
SHOWERS...AND IN THE LOWER 70S FRIDAY WITH LESS SHOWERS AND PERHAPS
SOME SUNSHINE.
&&
.LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/...
SRN STREAM DOMINATES THE CWA EARLY ON...WITH A WEAK WAVE MOVING
THROUGH LATE FRI NT INTO SAT. A NRN STREAM S/W TROUGH MAY STILL DIG
FAR ENOUGH S TO DRIVE A COLD FRONT AT LEAST INTO THE AREA LATE SAT.
THIS MAY BRING A BRIEF INTERLUDE OF DRY TO ONLY SCHC POPS AT LEAST
ACROSS THE N SAT NT INTO SUN.
SRN STREAM UPPER LOW LIFTS OUT OF THE DEEP S LATER SUN INTO MON AND
CROSSES THE CWA WITH ANOTHER ROUND OF PRECIPITATION. NRN STREAM
TROUGH AMPLIFICATION OVER THE CENTRAL AND ERN CONUS BEGINS EARLY
NEXT WEEK. MODELS ACTUALLY SHOW PHASING WITH THE SRN STREAM UPPER
LEVEL LOW ONCE THAT FEATURE IS PASSED THE AREA. THIS LEADS TO A
MILLER B TYPE SFC EVOLUTION WHICH BRINGS THE COLD FRONT ASSOCIATED
WITH THE FADING PRIMARY LOW THROUGH THE AREA SUN NT INTO MON. THIS
WOULD BE FOLLOWED BY DRYING DAY 7 NT.
TEMPERATURES A BIT HIGHER EARLY ON BUT OTHERWISE CLOSE TO PREVIOUS
WITH NO MAJOR DEVIATIONS FROM WPC INCLUDING THE NEW DAY 7.
&&
.AVIATION /22Z TUESDAY THROUGH SUNDAY/...
EXPECTING A SLOW DECREASE/SCATTERING OF THE SHOWERS ACROSS THE
AREA THROUGH THE EVENING AND INTO TONIGHT. SOUTHERN AND MOUNTAIN
TERMINALS WILL REMAIN SOCKED INTO THE LOWER MVFR CEILINGS/IFR
CEILINGS AT BKW WITHOUT ANY APPRECIABLE CHANGE OF AIRMASS IN THESE
LOCATIONS. SHOWERS WILL BE POSSIBLE THROUGH THE DURATION IN THE
SOUTHERN TERMINALS...BUT NOT HIGH ENOUGH CHANCE TO REQUIRE WEATHER
IN THE PREVAILING CONDITIONS. NORTHEASTERLY WINDS WILL ALSO BE A
PLAYER IN THE LOW CEILINGS IN THIS FORECAST.
EXPECT THE VISIBILITIES TO COME BACK TO VFR ONCE THE SHOWERS
END WITH WINDS IN THE 5-10KT RANGE.
FORECAST CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 00Z THURSDAY...
FORECAST CONFIDENCE: MEDIUM TO HIGH.
ALTERNATE SCENARIOS: TIMING OF SHOWERS ENDING MAY VARY. CEILINGS
COULD LIFT SOONER THAN FORECAST.
EXPERIMENTAL TABLE OF FLIGHT CATEGORY OBJECTIVELY SHOWS CONSISTENCY
OF WFO FORECAST TO AVAILABLE MODEL INFORMATION:
H = HIGH: TAF CONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.
M = MEDIUM: TAF HAS VARYING LEVEL OF CONSISTENCY WITH MODELS.
L = LOW: TAF INCONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.
UTC 1HRLY 20 21 22 23 00 01 02 03 04 05 06 07
EDT 1HRLY 16 17 18 19 20 21 22 23 00 01 02 03
CRW CONSISTENCY H H H H L H H L L L L H
HTS CONSISTENCY H M M M M M M M M M M M
BKW CONSISTENCY H H H H H H M M M M M M
EKN CONSISTENCY M M M M M M H H H H H H
PKB CONSISTENCY H H H H H H H H H H H H
CKB CONSISTENCY M M M M M M H H H H H H
AFTER 00Z THURSDAY...
IFR CONDITIONS POSSIBLE IN SHOWERS AND POSSIBLE THUNDERSTORMS AT
VARIOUS TIMES THRU THE WEEK.
&&
.RLX WATCHES/WARNINGS/ADVISORIES...
WV...FLOOD WATCH UNTIL 8 PM EDT THIS EVENING FOR WVZ005-013-015-016-
018-024>030-033>040-046-047.
OH...NONE.
KY...FLOOD WATCH UNTIL 8 PM EDT THIS EVENING FOR KYZ105.
VA...FLOOD WATCH UNTIL 8 PM EDT THIS EVENING FOR VAZ003-004.
&&
$$
SYNOPSIS...TRM/JMV/26
NEAR TERM...SL/26
SHORT TERM...JMV
LONG TERM...TRM
AVIATION...26
AREA FORECAST DISCUSSION
NWS CHARLESTON WV
347 PM EDT TUE APR 14 2015
.SYNOPSIS...
HIGH PRESSURE TRACKS NORTH OF THE AREA LATE TONIGHT INTO WEDNESDAY.
LOW PRESSURE TRACKS SOUTH OF THE AREA THURSDAY...AND ANOTHER ON
SATURDAY. A COLD FRONT MAY ARRIVE SATURDAY NIGHT.
&&
.NEAR TERM /THROUGH WEDNESDAY/...
LOOKING AT A DECREASE IN COVERAGE OF THE SHOWERS THROUGH THE
REMAINDER OF THIS AFTERNOON AND EVENING AS THE SURFACE LOW FINALLY
PASSES TO THROUGH THE SOUTHERN ZONES AND TOWARDS THE MID ATLANTIC
COAST. AS WE DRY OUT FROM THE RAINFALL LAST NIGHT AND TODAY...WE
WILL NOT BE ABLE TO USHER IN A DRY AIRMASS FOR THE ENTIRETY OF
THE CWA...WITH LOW LEVEL MOISTURE LINGERING IN THE COAL FIELDS
AND SOUTHERN MOUNTAINS. HIGH PRESSURE WILL BUILD IN FOR THE
NORTHERN ZONES...BUT AN INVERTED SURFACE TROUGH WILL ASSIST WITH
THE LOW LEVEL MOISTURE RETENTION. WILL ALSO KEEP LOW END POPS IN
THESE AREAS AS WELL. NO THUNDER EXPECTED THROUGH THE FORECAST.
FOLLOWED THE HRRR FOR THE DEVELOPMENT OF THE POPS THROUGH 00Z
WEDNESDAY. NORTHWESTERN ZONES WILL SEE SOME CLEARING TONIGHT.
IN THE UPPER LEVELS...GETTING A BRIEF REPRIEVE WITH MODEST RIDGING
TONIGHT INTO WEDNESDAY BEFORE THE NEXT ROUND OF EMBEDDED VORTICITY
MAXIMA IN THE 500MB FLOW ARRIVES IN THE TUG FORK VALLEY.
NORTHERN HALF OF THE CWA WILL LIKELY BE WARMER THAN THE SOUTHERN
HALF GIVEN THE CLEARER CONDITIONS ON WEDNESDAY.
&&
.SHORT TERM /WEDNESDAY NIGHT THROUGH FRIDAY/...
MODELS HAVE A MEAN UPPER TROUGH CONTINUING OVER THE WEST CENTRAL
PORTION OF THE NATION...WITH RATHER WEAK SOUTHWEST FLOW ALOFT
EXTENDING ACROSS THE OHIO AND TENNESSEE VALLEYS. THERE WILL BE WEAK
UPPER IMPULSES IN THIS SOUTHWEST FLOW ALOFT...BUT IT APPEARS MOST
MODELS FOCUS ON ONE THAT COMES ACROSS THURSDAY INTO THURSDAY NIGHT.
ALTHOUGH HIGH PRESSURE CENTERED OVER THE MID ATLANTIC STATES WILL BE
THE DOMINANT FEATURE AT THE SURFACE...THIS UPPER FEATURE APPEARS TO
HAVE ENOUGH DYNAMICS AND MOISTURE TO SQUEEZE OUT A HIGH POP AND LOW
QPF FORECAST THURSDAY AND EARLY THURSDAY NIGHT. OTHERWISE...HAVE TO
KEEP AT LEAST SLIGHT POPS IN MOST OF THE PERIOD...GIVEN THE
UNCERTAINTY OF OTHER IMPULSES ALOFT. THERE WILL BE LOTS OF CLOUDS
OUTSIDE OF ANY SHOWERS...ESPECIALLY THURSDAY...BUT LITTLE THUNDER
WITH MARGINAL MODEL INSTABILITY AT BEST. TEMPERATURES WILL BE
MODERATE WITH HIGHS THURSDAY IN THE MID 60S UNDER CLOUDS AND
SHOWERS...AND IN THE LOWER 70S FRIDAY WITH LESS SHOWERS AND PERHAPS
SOME SUNSHINE.
&&
.LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/...
SRN STREAM DOMINATES THE CWA EARLY ON...WITH A WEAK WAVE MOVING
THROUGH LATE FRI NT INTO SAT. A NRN STREAM S/W TROUGH MAY STILL DIG
FAR ENOUGH S TO DRIVE A COLD FRONT AT LEAST INTO THE AREA LATE SAT.
THIS MAY BRING A BRIEF INTERLUDE OF DRY TO ONLY SCHC POPS AT LEAST
ACROSS THE N SAT NT INTO SUN.
SRN STREAM UPPER LOW LIFTS OUT OF THE DEEP S LATER SUN INTO MON AND
CROSSES THE CWA WITH ANOTHER ROUND OF PRECIPITATION. NRN STREAM
TROUGH AMPLIFICATION OVER THE CENTRAL AND ERN CONUS BEGINS EARLY
NEXT WEEK. MODELS ACTUALLY SHOW PHASING WITH THE SRN STREAM UPPER
LEVEL LOW ONCE THAT FEATURE IS PASSED THE AREA. THIS LEADS TO A
MILLER B TYPE SFC EVOLUTION WHICH BRINGS THE COLD FRONT ASSOCIATED
WITH THE FADING PRIMARY LOW THROUGH THE AREA SUN NT INTO MON. THIS
WOULD BE FOLLOWED BY DRYING DAY 7 NT.
TEMPERATURES A BIT HIGHER EARLY ON BUT OTHERWISE CLOSE TO PREVIOUS
WITH NO MAJOR DEVIATIONS FROM WPC INCLUDING THE NEW DAY 7.
&&
.AVIATION /19Z TUESDAY THROUGH SUNDAY/...
EXPECTING A SLOW DECREASE/SCATTERING OF THE SHOWERS ACROSS THE
AREA THROUGH THE EVENING AND INTO TONIGHT. SOUTHERN AND MOUNTAIN
TERMINALS WILL REMAIN SOCKED INTO THE LOWER MVFR CEILINGS/IFR
CEILINGS AT BKW WITHOUT ANY APPRECIABLE CHANGE OF AIRMASS IN THESE
LOCATIONS. SHOWERS WILL BE POSSIBLE THROUGH THE DURATION IN THE
SOUTHERN TERMINALS...BUT NOT HIGH ENOUGH CHANCE TO REQUIRE WEATHER
IN THE PREVAILING CONDITIONS. NORTHEASTERLY WINDS WILL ALSO BE A
PLAYER IN THE LOW CEILINGS IN THIS FORECAST.
EXPECT THE VISIBILITIES TO COME BACK TO VFR ONCE THE SHOWERS
END WITH WINDS IN THE 5-10KT RANGE.
FORECAST CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 18Z WEDNESDAY...
FORECAST CONFIDENCE: MEDIUM TO HIGH.
ALTERNATE SCENARIOS: TIMING OF SHOWERS ENDING MAY VARY. CEILINGS
COULD LIFT SOONER THAN FORECAST.
EXPERIMENTAL TABLE OF FLIGHT CATEGORY OBJECTIVELY SHOWS CONSISTENCY
OF WFO FORECAST TO AVAILABLE MODEL INFORMATION:
H = HIGH: TAF CONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.
M = MEDIUM: TAF HAS VARYING LEVEL OF CONSISTENCY WITH MODELS.
L = LOW: TAF INCONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.
UTC 1HRLY 18 19 20 21 22 23 00 01 02 03 04 05
EDT 1HRLY 14 15 16 17 18 19 20 21 22 23 00 01
CRW CONSISTENCY H H H H H H L H H L L L
HTS CONSISTENCY H H H H H H M M M M M M
BKW CONSISTENCY H H H H H H H H M M M M
EKN CONSISTENCY M M M M M M M M H H H H
PKB CONSISTENCY H H H H H H H H H H H H
CKB CONSISTENCY M M M M M M M M H H H H
AFTER 18Z WEDNESDAY...
IFR CONDITIONS POSSIBLE IN SHOWERS AND POSSIBLE THUNDERSTORMS AT
VARIOUS TIMES THRU THE WEEK.
&&
.RLX WATCHES/WARNINGS/ADVISORIES...
WV...FLOOD WATCH UNTIL 8 PM EDT THIS EVENING FOR WVZ005-013-015-016-
018-024>030-033>040-046-047.
OH...NONE.
KY...FLOOD WATCH UNTIL 8 PM EDT THIS EVENING FOR KYZ105.
VA...FLOOD WATCH UNTIL 8 PM EDT THIS EVENING FOR VAZ003-004.
&&
$$
SYNOPSIS...TRM/JMV/26
NEAR TERM...26
SHORT TERM...JMV
LONG TERM...TRM
AVIATION...26
AREA FORECAST DISCUSSION
NWS CHARLESTON WV
248 PM EDT TUE APR 14 2015
.SYNOPSIS...
LOW PRESSURE PASSES TO THE SOUTH. HIGH PRESSURE TRACKS NORTH OF
THE AREA LATE TONIGHT AND INTO WEDNESDAY. WEAK DISTURBANCES KEEP
THE WEATHER UNSETTLED THROUGH LATE WEEK.
&&
.NEAR TERM /THROUGH WEDNESDAY/...
LOOKING AT A DECREASE IN COVERAGE OF THE SHOWERS THROUGH THE
REMAINDER OF THIS AFTERNOON AND EVENING AS THE SURFACE LOW FINALLY
PASSES TO THROUGH THE SOUTHERN ZONES AND TOWARDS THE MID ATLANTIC
COAST. AS WE DRY OUT FROM THE RAINFALL LAST NIGHT AND TODAY...WE
WILL NOT BE ABLE TO USHER IN A DRY AIRMASS FOR THE ENTIRETY OF
THE CWA...WITH LOW LEVEL MOISTURE LINGERING IN THE COAL FIELDS
AND SOUTHERN MOUNTAINS. HIGH PRESSURE WILL BUILD IN FOR THE
NORTHERN ZONES...BUT AN INVERTED SURFACE TROUGH WILL ASSIST WITH
THE LOW LEVEL MOISTURE RETENTION. WILL ALSO KEEP LOW END POPS IN
THESE AREAS AS WELL. NO THUNDER EXPECTED THROUGH THE FORECAST.
FOLLOWED THE HRRR FOR THE DEVELOPMENT OF THE POPS THROUGH 00Z
WEDNESDAY. NORTHWESTERN ZONES WILL SEE SOME CLEARING TONIGHT.
IN THE UPPER LEVELS...GETTING A BRIEF REPRIEVE WITH MODEST RIDGING
TONIGHT INTO WEDNESDAY BEFORE THE NEXT ROUND OF EMBEDDED VORTICITY
MAXIMA IN THE 500MB FLOW ARRIVES IN THE TUG FORK VALLEY.
NORTHERN HALF OF THE CWA WILL LIKELY BE WARMER THAN THE SOUTHERN
HALF GIVEN THE CLEARER CONDITIONS ON WEDNESDAY.
&&
.SHORT TERM /WEDNESDAY NIGHT THROUGH FRIDAY/...
MODELS HAVE A MEAN UPPER TROUGH CONTINUING OVER THE WEST CENTRAL
PORTION OF THE NATION...WITH RATHER WEAK SOUTHWEST FLOW ALOFT
EXTENDING ACROSS THE OHIO AND TENNESSEE VALLEYS. THERE WILL BE WEAK
UPPER IMPULSES IN THIS SOUTHWEST FLOW ALOFT...BUT IT APPEARS MOST
MODELS FOCUS ON ONE THAT COMES ACROSS THURSDAY INTO THURSDAY NIGHT.
ALTHOUGH HIGH PRESSURE CENTERED OVER THE MID ATLANTIC STATES WILL BE
THE DOMINANT FEATURE AT THE SURFACE...THIS UPPER FEATURE APPEARS TO
HAVE ENOUGH DYNAMICS AND MOISTURE TO SQUEEZE OUT A HIGH POP AND LOW
QPF FORECAST THURSDAY AND EARLY THURSDAY NIGHT. OTHERWISE...HAVE TO
KEEP AT LEAST SLIGHT POPS IN MOST OF THE PERIOD...GIVEN THE
UNCERTAINTY OF OTHER IMPULSES ALOFT. THERE WILL BE LOTS OF CLOUDS
OUTSIDE OF ANY SHOWERS...ESPECIALLY THURSDAY...BUT LITTLE THUNDER
WITH MARGINAL MODEL INSTABILITY AT BEST. TEMPERATURES WILL BE
MODERATE WITH HIGHS THURSDAY IN THE MID 60S UNDER CLOUDS AND
SHOWERS...AND IN THE LOWER 70S FRIDAY WITH LESS SHOWERS AND PERHAPS
SOME SUNSHINE.
&&
.LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/...
PERIOD BEGINS WITH THE AREA DOMINATED BY A WEAK SOUTHERN STREAM
JET...WITH THE ELEPHANT IN THE ROOM BEING THE NORTHERN JET...WHICH
SUPPOSEDLY WORKS ITS WAY FARTHER AND FARTHER S...AS MEAN L/W
TROUGHINESS SETS UP OVER THE CENTRAL AND EASTERN CONUS.
AT THE SFC...SRLY FLOW OUT OF THE GULF BRINGS INCREASING MOISTURE
NWD INTO THE AREA THU NT INTO SAT...BEFORE A COLD FRONT INTERCEPTS
THIS FLOW LATE SAT OR SAT NT. THE SWD PENETRATION OF THIS FRONT
DEPENDS UPON THE DEGREE OF INTRUSION OF THE ASSOCIATED NRN STREAM
S/W TROUGH INTO THE CONUS...AS A SRN STREAM CLOSED OFF LOW BEGINS
MOVING NEWD OUT OF THE DEEP S. THIS IS WHERE MODELS BEGIN TO
DIVERGE CONSIDERABLY...MAKING FOR A RATHER UNCERTAIN FCST. ROLLED
WITH SCHC ACROSS MUCH OF THE AREA SAT NT AND SUN...THESE ARE THE
LOWEST POPS IN THE FCST.
EITHER WAY...THE NRN STREAM LIFTS OUT SUN...ALLOWING THE THE SRN
STREAM UPPER LOW TO APPROACH...AND THEN MOVE ON THROUGH SUN NT.
THIS BRINGS UNSETTLED WEATHER BACK INTO THE AREA. NRN STREAM FLOW
TROUGH AMPLIFICATION OVER THE CENTRAL AND ERN CONUS BEGINS EARLY
NEXT WEEK. MODELS ACTUALLY SHOW PHASING WITH THE SRN STREAM UPPER
LEVEL LOW ONCE THAT FEATURE IS PASSED THE AREA. THIS SHOULD LEAD TO
CONTINUED UNSETTLED WEATHER THROUGH DAY 7 NT...AND...EVENTUALLY...A
TREND TOWARD COOLER WEATHER AS WELL.
NOT MUCH TEMPERATURE CHANGES IN A PATTERN FRAUGHT WITH UNCERTAINTY
AS TO THE TIMING OF CLOUDS AND PRECIPITATION. THE FCST IS ALSO
CLOSE TO WPC...AND BIAS CORRECTED ECMWF EXCEPT THE WEEKEND...WHEN
ITS DRY COOL SOLN IS THE ODD ONE OUT.
&&
.AVIATION /19Z TUESDAY THROUGH SUNDAY/...
EXPECTING A SLOW DECREASE/SCATTERING OF THE SHOWERS ACROSS THE
AREA THROUGH THE EVENING AND INTO TONIGHT. SOUTHERN AND MOUNTAIN
TERMINALS WILL REMAIN SOCKED INTO THE LOWER MVFR CEILINGS/IFR
CEILINGS AT BKW WITHOUT ANY APPRECIABLE CHANGE OF AIRMASS IN THESE
LOCATIONS. SHOWERS WILL BE POSSIBLE THROUGH THE DURATION IN THE
SOUTHERN TERMINALS...BUT NOT HIGH ENOUGH CHANCE TO REQUIRE WEATHER
IN THE PREVAILING CONDITIONS. NORTHEASTERLY WINDS WILL ALSO BE A
PLAYER IN THE LOW CEILINGS IN THIS FORECAST.
EXPECT THE VISIBILITIES TO COME BACK TO VFR ONCE THE SHOWERS
END WITH WINDS IN THE 5-10KT RANGE.
FORECAST CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 18Z WEDNESDAY...
FORECAST CONFIDENCE: MEDIUM TO HIGH.
ALTERNATE SCENARIOS: TIMING OF SHOWERS ENDING MAY VARY. CEILINGS
COULD LIFT SOONER THAN FORECAST.
EXPERIMENTAL TABLE OF FLIGHT CATEGORY OBJECTIVELY SHOWS CONSISTENCY
OF WFO FORECAST TO AVAILABLE MODEL INFORMATION:
H = HIGH: TAF CONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.
M = MEDIUM: TAF HAS VARYING LEVEL OF CONSISTENCY WITH MODELS.
L = LOW: TAF INCONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.
UTC 1HRLY 18 19 20 21 22 23 00 01 02 03 04 05
EDT 1HRLY 14 15 16 17 18 19 20 21 22 23 00 01
CRW CONSISTENCY H H H H H H L H H L L L
HTS CONSISTENCY H H H H H H M M M M M M
BKW CONSISTENCY H H H H H H H H M M M M
EKN CONSISTENCY M M M M M M M M H H H H
PKB CONSISTENCY H H H H H H H H H H H H
CKB CONSISTENCY M M M M M M M M H H H H
AFTER 18Z WEDNESDAY...
IFR CONDITIONS POSSIBLE IN SHOWERS AND POSSIBLE THUNDERSTORMS AT
VARIOUS TIMES THRU THE WEEK.
&&
.RLX WATCHES/WARNINGS/ADVISORIES...
WV...FLOOD WATCH UNTIL 8 PM EDT THIS EVENING FOR WVZ005-013-015-016-
018-024>030-033>040-046-047.
OH...NONE.
KY...FLOOD WATCH UNTIL 8 PM EDT THIS EVENING FOR KYZ105.
VA...FLOOD WATCH UNTIL 8 PM EDT THIS EVENING FOR VAZ003-004.
&&
$$
SYNOPSIS...JMV/26
NEAR TERM...26
SHORT TERM...JMV
LONG TERM...TRM
AVIATION...26
AREA FORECAST DISCUSSION
NWS CHARLESTON WV
223 PM EDT TUE APR 14 2015
.SYNOPSIS...
LOW PRESSURE PASSES TO THE SOUTH. HIGH PRESSURE TRACKS NORTH OF
THE AREA LATE TONIGHT AND INTO WEDNESDAY. WEAK DISTURBANCES KEEP
THE WEATHER UNSETTLED THROUGH LATE WEEK.
&&
.NEAR TERM /THROUGH WEDNESDAY/...
LOOKING AT A DECREASE IN COVERAGE OF THE SHOWERS THROUGH THE
REMAINDER OF THIS AFTERNOON AND EVENING AS THE SURFACE LOW FINALLY
PASSES TO THROUGH THE SOUTHERN ZONES AND TOWARDS THE MID ATLANTIC
COAST. AS WE DRY OUT FROM THE RAINFALL LAST NIGHT AND TODAY...WE
WILL NOT BE ABLE TO USHER IN A DRY AIRMASS FOR THE ENTIRETY OF
THE CWA...WITH LOW LEVEL MOISTURE LINGERING IN THE COAL FIELDS
AND SOUTHERN MOUNTAINS. HIGH PRESSURE WILL BUILD IN FOR THE
NORTHERN ZONES...BUT AN INVERTED SURFACE TROUGH WILL ASSIST WITH
THE LOW LEVEL MOISTURE RETENTION. WILL ALSO KEEP LOW END POPS IN
THESE AREAS AS WELL. NO THUNDER EXPECTED THROUGH THE FORECAST.
FOLLOWED THE HRRR FOR THE DEVELOPMENT OF THE POPS THROUGH 00Z
WEDNESDAY. NORTHWESTERN ZONES WILL SEE SOME CLEARING TONIGHT.
IN THE UPPER LEVELS...GETTING A BRIEF REPRIEVE WITH MODEST RIDGING
TONIGHT INTO WEDNESDAY BEFORE THE NEXT ROUND OF EMBEDDED VORTICITY
MAXIMA IN THE 500MB FLOW ARRIVES IN THE TUG FORK VALLEY.
NORTHERN HALF OF THE CWA WILL LIKELY BE WARMER THAN THE SOUTHERN
HALF GIVEN THE CLEARER CONDITIONS ON WEDNESDAY.
&&
.SHORT TERM /WEDNESDAY NIGHT THROUGH THURSDAY NIGHT/...
HIGH PRESSURE STAYS IN CONTROL KEEPING MOST OF THE AREA DRY FOR
WEDNESDAY. THE EXCEPTION WILL BE THE EXTREME SOUTHERN SECTIONS OF
WV...SOUTHWEST VA...AND NORTHEAST OH WHERE MODELS INDICATE WINDS
WILL SHIFT FROM THE SOUTH BRINGING MOISTURE BACK TO THE
AREA...ALONG WITH PASSING MID LEVEL WEAK SHORT WAVES. THE NAM AND
CMC SHOW THIS MOISTURE IN THEIR QPF FIELDS ON THESE AREAS.
THEREFORE...KEPT CHANCE POPS TO ACCOUNT FOR RAIN SHOWERS. ALMOST
NO INSTABILITY IS NOTED...SO KEPT THUNDER OUT OF THE FORECAST.
A SERIES OF MID LEVEL WAVES WILL CONTINUE TO PASS...AS SEEN ON
WEAK VORTICITY MAXES...UNDER A MID LEVEL RIDGE WEDNESDAY NIGHT
AND THURSDAY. AS MOISTURE INCREASES UNDER SOUTH SOUTHEASTERLY
FLOW...SO THE POPS ACROSS THE AREA UP TO 50 PERCENT BY THURSDAY.
FORECAST BECOMES TRICKY AS THE INFLUENCE OF THESE MID LEVEL SHORT
WAVES WILL HAVE OVER THE AREA THROUGH THURSDAY NIGHT. THEREFORE...KEPT
CHANCE POPS THROUGH THURSDAY NIGHT.
WENT CLOSER TO THE ALL BLEND NUMBERS FOR TEMPERATURES THROUGH THE
PERIOD.
&&
.LONG TERM /FRIDAY THROUGH TUESDAY/...
PERIOD BEGINS WITH THE AREA DOMINATED BY A WEAK SOUTHERN STREAM
JET...WITH THE ELEPHANT IN THE ROOM BEING THE NORTHERN JET...WHICH
SUPPOSEDLY WORKS ITS WAY FARTHER AND FARTHER S...AS MEAN L/W
TROUGHINESS SETS UP OVER THE CENTRAL AND EASTERN CONUS.
AT THE SFC...SRLY FLOW OUT OF THE GULF BRINGS INCREASING MOISTURE
NWD INTO THE AREA THU NT INTO SAT...BEFORE A COLD FRONT INTERCEPTS
THIS FLOW LATE SAT OR SAT NT. THE SWD PENETRATION OF THIS FRONT
DEPENDS UPON THE DEGREE OF INTRUSION OF THE ASSOCIATED NRN STREAM
S/W TROUGH INTO THE CONUS...AS A SRN STREAM CLOSED OFF LOW BEGINS
MOVING NEWD OUT OF THE DEEP S. THIS IS WHERE MODELS BEGIN TO
DIVERGE CONSIDERABLY...MAKING FOR A RATHER UNCERTAIN FCST. ROLLED
WITH SCHC ACROSS MUCH OF THE AREA SAT NT AND SUN...THESE ARE THE
LOWEST POPS IN THE FCST.
EITHER WAY...THE NRN STREAM LIFTS OUT SUN...ALLOWING THE THE SRN
STREAM UPPER LOW TO APPROACH...AND THEN MOVE ON THROUGH SUN NT.
THIS BRINGS UNSETTLED WEATHER BACK INTO THE AREA. NRN STREAM FLOW
TROUGH AMPLIFICATION OVER THE CENTRAL AND ERN CONUS BEGINS EARLY
NEXT WEEK. MODELS ACTUALLY SHOW PHASING WITH THE SRN STREAM UPPER
LEVEL LOW ONCE THAT FEATURE IS PASSED THE AREA. THIS SHOULD LEAD TO
CONTINUED UNSETTLED WEATHER THROUGH DAY 7 NT...AND...EVENTUALLY...A
TREND TOWARD COOLER WEATHER AS WELL.
NOT MUCH TEMPERATURE CHANGES IN A PATTERN FRAUGHT WITH UNCERTAINTY
AS TO THE TIMING OF CLOUDS AND PRECIPITATION. THE FCST IS ALSO
CLOSE TO WPC...AND BIAS CORRECTED ECMWF EXCEPT THE WEEKEND...WHEN
ITS DRY COOL SOLN IS THE ODD ONE OUT.
&&
.AVIATION /18Z TUESDAY THROUGH SUNDAY/...
EXPECTING A SLOW DECREASE/SCATTERING OF THE SHOWERS ACROSS THE
AREA THROUGH THE EVENING AND INTO TONIGHT. SOUTHERN AND MOUNTAIN
TERMINALS WILL REMAIN SOCKED INTO THE LOWER MVFR CEILINGS/IFR
CEILINGS AT BKW WITHOUT ANY APPRECIABLE CHANGE OF AIRMASS IN THESE
LOCATIONS. SHOWERS WILL BE POSSIBLE THROUGH THE DURATION IN THE
SOUTHERN TERMINALS...BUT NOT HIGH ENOUGH CHANCE TO REQUIRE WEATHER
IN THE PREVAILING CONDITIONS. NORTHEASTERLY WINDS WILL ALSO BE A
PLAYER IN THE LOW CEILINGS IN THIS FORECAST.
EXPECT THE VISIBILITIES TO COME BACK TO VFR ONCE THE SHOWERS
END WITH WINDS IN THE 5-10KT RANGE.
FORECAST CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 18Z WEDNESDAY...
FORECAST CONFIDENCE: MEDIUM TO HIGH.
ALTERNATE SCENARIOS: TIMING OF SHOWERS ENDING MAY VARY. CEILINGS
COULD LIFT SOONER THAN FORECAST.
EXPERIMENTAL TABLE OF FLIGHT CATEGORY OBJECTIVELY SHOWS CONSISTENCY
OF WFO FORECAST TO AVAILABLE MODEL INFORMATION:
H = HIGH: TAF CONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.
M = MEDIUM: TAF HAS VARYING LEVEL OF CONSISTENCY WITH MODELS.
L = LOW: TAF INCONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.
UTC 1HRLY 18 19 20 21 22 23 00 01 02 03 04 05
EDT 1HRLY 14 15 16 17 18 19 20 21 22 23 00 01
CRW CONSISTENCY H H H H H H L H H L L L
HTS CONSISTENCY H H H H H H M M M M M M
BKW CONSISTENCY H H H H H H H H M M M M
EKN CONSISTENCY M M M M M M M M H H H H
PKB CONSISTENCY H H H H H H H H H H H H
CKB CONSISTENCY M M M M M M M M H H H H
AFTER 18Z WEDNESDAY...
IFR CONDITIONS POSSIBLE IN SHOWERS AND POSSIBLE THUNDERSTORMS AT
VARIOUS TIMES THRU THE WEEK.
&&
.RLX WATCHES/WARNINGS/ADVISORIES...
WV...FLOOD WATCH UNTIL 8 PM EDT THIS EVENING FOR WVZ005-013-015-016-
018-024>030-033>040-046-047.
FLOOD WATCH UNTIL 3 PM EDT THIS AFTERNOON FOR WVZ006>008-014.
OH...FLOOD WATCH UNTIL 3 PM EDT THIS AFTERNOON FOR OHZ085>087.
KY...FLOOD WATCH UNTIL 8 PM EDT THIS EVENING FOR KYZ105.
FLOOD WATCH UNTIL 3 PM EDT THIS AFTERNOON FOR KYZ101>103.
VA...FLOOD WATCH UNTIL 8 PM EDT THIS EVENING FOR VAZ003-004.
&&
$$
SYNOPSIS...ARJ/26
NEAR TERM...26
SHORT TERM...ARJ
LONG TERM...TRM
AVIATION...26
AREA FORECAST DISCUSSION
NWS WILMINGTON OH
156 PM EDT TUE APR 14 2015
.SYNOPSIS...
HIGH PRESSURE IN THE GREAT LAKES AND LOW PRESSURE IN THE TENNESSEE
VALLEY WILL HAVE A COOL AIRMASS OVER THE OHIO VALLEY WITH RAIN ENDING
OVER THE SOUTHERN OHIO VALLEY THIS MORNING. THE HIGH WILL CONTINUE
TO PUSH DRIER AND SOMEWHAT COOL AIR TO THE REGION THROUGH
WEDNESDAY. A SURFACE TROUGH WILL NOSE NORTHEAST INTO OHIO ON
THURSDAY AND BRING AN INCREASED THREAT FOR MORE SHOWERS.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
A SURFACE LOW PRESSURE SYSTEM OVER THE CENTRAL TENNESSEE VALLEY
WILL PUSH OFF TO THE EAST THROUGH THIS AFTERNOON. WIDESPREAD RAIN
ASSOCIATED WITH THIS CONTINUES TO AFFECT PRIMARILY AREAS TO OUR
SOUTH...BUT THERE HAS BEEN AN EVER SO SLIGHT NORTHWARD PUSH TO
THE PCPN SHIELD IN THE LAST FEW HOURS. THE LATEST RAP SEEMS TO
HAVE THE BEST HANDLE ON THE SITUATION AND IS HANGING ON TO A WEAK
850-700 MB DEFORMATION AXIS ACROSS OUR SOUTHERN AREAS THROUGH
EARLY AFTERNOON. BASED ON THIS AND RADAR TRENDS...WILL NUDGE UP
POPS ACROSS OUR FAR SOUTH THROUGH THE REST OF THE MORNING. AS THE
LOW BEGINS TO PUSH OFF TO THE EAST...PCPN SHOULD TAPER OFF
THROUGH THIS AFTERNOON. EXPECT COOLEST TEMPS TODAY ACROSS OUR FAR
SOUTH DUE TO THE CLOUDS AND PCPN WITH HIGHS. GENERALLY EXPECT HIGHS
IN THE LOW TO MID 60S.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH FRIDAY NIGHT/...
NORTHEAST WIND WILL CONTINUE TO BRING IN DRIER AIR TO THE OHIO
VALLEY ALONG WITH A GENERALLY MUTED AND STAGNANT TEMPERATURE
CHANGE OVER THE NEXT FEW DAYS. READINGS SHOULD TOP OUT IN THE MID
60S WED AND THURS AND WARM TO THE UPPER 60S FRIDAY. OVERNIGHT LOWS
WILL DIP TO THE LOW AND MID 40S TONIGHT AND SLOWLY RISE TO THE
LOWER 50S THURSDAY NIGHT.
AN INVERTED TROUGH WILL NOSE NORTHEAST INTO OHIO WED NIGHT AND SEE
INCREASED SHOWER ACTIVITY WITH IT. MODELS ARE DISJOINTED IN THE
AREAL COVERAGE OF QPF THURSDAY AND OVERNIGHT...AND THE INVERTED
TROUGH TYPICALLY IS NOT ENOUGH ON ITS OWN TO BRING WIDESPREAD
SHOWERS. H5 RIDGE IN PLACE WEDNESDAY WILL BREAK DOWN AND MOVE EAST
THURSDAY WITH A LOBE OF VORTICITY IN A VERY WEAK S/W PASSING OVER
THE REGION AT 0Z FRI. H5 FLOW IS GENERALLY ZONAL WESTERLY BEYOND
THIS PERIOD.
ADJUSTED WEATHER TO REMOVE THUNDER THROUGH SATURDAY AS NO FOCUS
FOR DEEP CONVECTION APPEARS TO PRESENT ITSELF IN THE FORECAST
THROUGH THIS TIME. AN ISOLATED RUMBLE CAN`T BE RULED OUT BUT THE
DAY1-3 OUTLOOK DID NOT INCLUDE THE REGION IN GENERAL THUNDER SO I
EXTENDED THIS IDEA INTO DAY 4.
&&
.LONG TERM /SATURDAY THROUGH MONDAY/...
MODEL SOLN DIFFERENCES DEVELOP WITH GFS KEEPING THE AREA WET AND
PHASING THE FLOWS. MEANWHILE...ECMWF/CMC/DGEX KEEP A SPLIT FLOW.
WILL FOLLOW THIS SPLIT FLOW SOLN WITH INITIAL WAVE PASSING TO THE
EAST BUT ANOTHER NRN S/W PASSING THRU LATE FRIDAY NIGHT. THIS WILL
KEEP A CHANCE OF PCPN INTO LATE FRIDAY NIGHT/EARLY SATURDAY TIME
FRAME.
WILL THEN ALLOW FOR A DRY PERIOD LATER SATURDAY AND SUNDAY WITH MID
LEVEL RIDGE BUILDING INTO THE GREAT LAKES/OHIO VALLEY. TEMPERATURES
TO STAY ABOVE NORMAL WITH HIGHS NEXT WEEKEND FROM THE LOWER 60S FAR
N TO NEAR 70 FAR SOUTH.
ANOTHER CHANCE FOR SHOWERS/THUNDERSTORMS RETURNS LATE SUNDAY
NIGHT/MONDAY AS THE NEXT S/W AND ASSOCIATED SFC LOW ARE EXPECTED TO
EJECT NE INTO THE OHIO VALLEY.
&&
.AVIATION /18Z TUESDAY THROUGH SUNDAY/...
A SURFACE LOW PRESSURE SYSTEM OVER THE TENNESSEE VALLEY WILL
CONTINUE TO SHIFT OFF TO THE EAST THROUGH EARLY EVENING. PCPN
ASSOCIATED WITH THIS HAS GENERALLY REMAINED SOUTH OF KCVG/KLUK
BUT SUPPOSE THEY COULD STILL SEE A FEW SPRINKLES OVER THE NEXT
HOUR OR SO. OTHERWISE...ANY PCPN THREAT FOR THEM SHOULD CUT OFF
THROUGH MID AFTERNOON AS DRYING BEGINS WORKING IN FROM THE WEST.
RIDGING WILL THEN BUILD INTO THE AREA TONIGHT INTO WEDNESDAY WITH
PRIMARILY JUST SOME MID AND HIGH LEVEL CLOUDINESS EXPECTED. WE WILL
START TO GET INTO SOME DEVELOPING ISENTROPIC LIFT LATER IN THE
DAY ON WEDNESDAY AND THIS WILL LIKELY LEAD TO A LOWERING VFR DECK
TOWARD THE END OF THE KCVG TAF PERIOD.
OUTLOOK...SHOWERS AND ISOLATED THUNDERSTORMS WILL BE POSSIBLE AT
TIMES FROM WEDNESDAY NIGHT THROUGH FRIDAY.
&&
.ILN WATCHES/WARNINGS/ADVISORIES...
OH...NONE.
KY...NONE.
IN...NONE.
&&
$$
SYNOPSIS...FRANKS
NEAR TERM...JGL
SHORT TERM...FRANKS
LONG TERM...AR
AVIATION...JGL
AREA FORECAST DISCUSSION
NWS WILMINGTON OH
913 AM EDT TUE APR 14 2015
.SYNOPSIS...
HIGH PRESSURE IN THE GREAT LAKES AND LOW PRESSURE IN THE TENNESSEE
VALLEY WILL HAVE A COOL AIRMASS OVER THE OHIO VALLEY WITH RAIN ENDING
OVER THE SOUTHERN OHIO VALLEY THIS MORNING. THE HIGH WILL CONTINUE
TO PUSH DRIER AND SOMEWHAT COOL AIR TO THE REGION THROUGH
WEDNESDAY. A SURFACE TROUGH WILL NOSE NORTHEAST INTO OHIO ON
THURSDAY AND BRING AN INCREASED THREAT FOR MORE SHOWERS.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
A SURFACE LOW PRESSURE SYSTEM OVER THE CENTRAL TENNESSEE VALLEY
WILL PUSH OFF TO THE EAST THROUGH THIS AFTERNOON. WIDESPREAD RAIN
ASSOCIATED WITH THIS CONTINUES TO AFFECT PRIMARILY AREAS TO OUR
SOUTH...BUT THERE HAS BEEN AN EVER SO SLIGHT NORTHWARD PUSH TO
THE PCPN SHIELD IN THE LAST FEW HOURS. THE LATEST RAP SEEMS TO
HAVE THE BEST HANDLE ON THE SITUATION AND IS HANGING ON TO A WEAK
850-700 MB DEFORMATION AXIS ACROSS OUR SOUTHERN AREAS THROUGH
EARLY AFTERNOON. BASED ON THIS AND RADAR TRENDS...WILL NUDGE UP
POPS ACROSS OUR FAR SOUTH THROUGH THE REST OF THE MORNING. AS THE
LOW BEGINS TO PUSH OFF TO THE EAST...PCPN SHOULD TAPER OFF
THROUGH THIS AFTERNOON. EXPECT COOLEST TEMPS TODAY ACROSS OUR FAR
SOUTH DUE TO THE CLOUDS AND PCPN WITH HIGHS. GENERALLY EXPECT HIGHS
IN THE LOW TO MID 60S.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH FRIDAY NIGHT/...
NORTHEAST WIND WILL CONTINUE TO BRING IN DRIER AIR TO THE OHIO
VALLEY ALONG WITH A GENERALLY MUTED AND STAGNANT TEMPERATURE
CHANGE OVER THE NEXT FEW DAYS. READINGS SHOULD TOP OUT IN THE MID
60S WED AND THURS AND WARM TO THE UPPER 60S FRIDAY. OVERNIGHT LOWS
WILL DIP TO THE LOW AND MID 40S TONIGHT AND SLOWLY RISE TO THE
LOWER 50S THURSDAY NIGHT.
AN INVERTED TROUGH WILL NOSE NORTHEAST INTO OHIO WED NIGHT AND SEE
INCREASED SHOWER ACTIVITY WITH IT. MODELS ARE DISJOINTED IN THE
AREAL COVERAGE OF QPF THURSDAY AND OVERNIGHT...AND THE INVERTED
TROUGH TYPICALLY IS NOT ENOUGH ON ITS OWN TO BRING WIDESPREAD
SHOWERS. H5 RIDGE IN PLACE WEDNESDAY WILL BREAK DOWN AND MOVE EAST
THURSDAY WITH A LOBE OF VORTICITY IN A VERY WEAK S/W PASSING OVER
THE REGION AT 0Z FRI. H5 FLOW IS GENERALLY ZONAL WESTERLY BEYOND
THIS PERIOD.
ADJUSTED WEATHER TO REMOVE THUNDER THROUGH SATURDAY AS NO FOCUS
FOR DEEP CONVECTION APPEARS TO PRESENT ITSELF IN THE FORECAST
THROUGH THIS TIME. AN ISOLATED RUMBLE CAN`T BE RULED OUT BUT THE
DAY1-3 OUTLOOK DID NOT INCLUDE THE REGION IN GENERAL THUNDER SO I
EXTENDED THIS IDEA INTO DAY 4.
&&
.LONG TERM /SATURDAY THROUGH MONDAY/...
MODEL SOLN DIFFERENCES DEVELOP WITH GFS KEEPING THE AREA WET AND
PHASING THE FLOWS. MEANWHILE...ECMWF/CMC/DGEX KEEP A SPLIT FLOW.
WILL FOLLOW THIS SPLIT FLOW SOLN WITH INITIAL WAVE PASSING TO THE
EAST BUT ANOTHER NRN S/W PASSING THRU LATE FRIDAY NIGHT. THIS WILL
KEEP A CHANCE OF PCPN INTO LATE FRIDAY NIGHT/EARLY SATURDAY TIME
FRAME.
WILL THEN ALLOW FOR A DRY PERIOD LATER SATURDAY AND SUNDAY WITH MID
LEVEL RIDGE BUILDING INTO THE GREAT LAKES/OHIO VALLEY. TEMPERATURES
TO STAY ABOVE NORMAL WITH HIGHS NEXT WEEKEND FROM THE LOWER 60S FAR
N TO NEAR 70 FAR SOUTH.
ANOTHER CHANCE FOR SHOWERS/THUNDERSTORMS RETURNS LATE SUNDAY
NIGHT/MONDAY AS THE NEXT S/W AND ASSOCIATED SFC LOW ARE EXPECTED TO
EJECT NE INTO THE OHIO VALLEY.
&&
.AVIATION /13Z TUESDAY THROUGH SATURDAY/...
CDFNT AND PCPN HAS PUSHED SOUTH OF THE TAFS LEAVING VFR
CONDITIONS. AFT 12Z...LOW PRESSURE WILL RIPPLE ALONG STALLED
FRONTAL BOUNDARY IN KY/TN. 00Z MODELS ARE SPREADING SOME LIGHT PCPN
PRECIPITATION N INTO THE SRN TAFS. WILL COVER THIS AT THE CVG/LUK
TAFS WITH A VCSH BETWEEN 15-21Z.
PRESSURE GRADIENT WILL TIGHTEN WITH PASSAGE OF THE LOW. WINDS WILL
GUST UP INTO THE LOWER 20 KNOTS BETWEEN 15Z AND 23Z.
OUTLOOK...SHOWERS AND THUNDERSTORMS WILL BE POSSIBLE AT TIMES FROM
WEDNESDAY NIGHT THROUGH FRIDAY.
&&
.ILN WATCHES/WARNINGS/ADVISORIES...
OH...NONE.
KY...NONE.
IN...NONE.
&&
$$
SYNOPSIS...FRANKS
NEAR TERM...JGL
SHORT TERM...FRANKS
LONG TERM...AR
AVIATION...SITES
AREA FORECAST DISCUSSION
NWS NORMAN OK
1233 PM CDT TUE APR 14 2015
.UPDATE...
18Z TAFS... MVFR/VFR CEILINGS THIS TAF PERIOD. A FEW MODELS
SUGGEST IFR CONDITIONS LATE TONIGHT/EARLY WED BUT FOR NOW HAVE
LEFT AT HIGHER CEILINGS. DRIZZLE/LIGHT RAIN WILL AFFECT A FEW OF
THE TAF SITES THIS AFTN BUT STORM SYSTEM IS SLOWLY MOVING ACROSS
THE AREA CAUSE PRECIP TO SLOWLY END. WINDS WILL GENERALLY BE
SHIFTING TOWARDS THE SE THROUGH THE TAF PERIOD.
&&
.PREV DISCUSSION... /ISSUED 1112 AM CDT TUE APR 14 2015/
UPDATE...
ADJUSTED RAIN CHANCES THIS AFTERNOON TO LOWER THEM IN
WESTERN OKLAHOMA AND INCREASE THEM EAST OF I-40. ALSO...ADJUSTED
HIGHS UPWARDS IN NORTHWEST OKLAHOMA AND DOWNWARDS SOUTHEAST OF
I-44. DECREASED CLOUD COVER THIS AFTERNOON IN WESTERN OKLAHOMA.
DISCUSSION...
LIGHT RAIN WILL SLOWLY DECREASE IN COVERAGE THIS AFTERNOON AS
THE MID/UPPER LOW DEPARTS THE AREA.
LATEST RADARS INDICATED AREAS OF LIGHT RAIN/SPRINKLES MAINLY EAST
OF A CHEROKEE TO ALTUS TO CROWELL LINE. TWO AREAS OF HIGHER
COVERAGE EXISTED FROM NEAR PAULS VALLEY TO MCALESTER AND ANOTHER
AREA WAS EAST OF ENID TO PERRY TO JUST SOUTH OF PONCA CITY.
ADJUSTED RAIN CHANCES TO ACCOUNT FOR THESE AREAS. ADDITIONAL
RAINFALL TODAY MAY BE UP TO ONE HALF INCH IN THESE LOCATIONS.
STILL BELIEVE LIGHT RAIN COVERAGE WILL DECREASE THIS AFTERNOON IN
AGREEMENT WITH THE LATEST HRRR RUNS. THUS TWEAKED RAIN CHANCES
ACCORDINGLY. ADDITIONAL RAINFALL WILL ONLY BE A FEW HUNDREDTHS IN
MANY LOCATIONS. BELIEVE RAIN HAS ENDED WEST OF A CHEROKEE TO ALTUS
LINE.
CLOUD COVER AND RAIN WILL KEEP TEMPERATURES DOWN TODAY...
ESPECIALLY SOUTHEAST OF I-44 WHERE MOISTURE IS DEEPEST...SO
LOWERED TEMPERATURES. ON THE OTHER HAND...SOME CLEARING IS ALREADY
OCCURRING IN WESTERN OKLAHOMA...SO TEMPERATURES WERE INCREASED
THERE.
PRODUCTS HAVE BEEN UPDATED.
MBS
PREV DISCUSSION... /ISSUED 425 AM CDT TUE APR 14 2015/
DISCUSSION...
UPPER LOW OVER SOUTHWEST OKLAHOMA CONTINUES TO WADDLE SLOWLY
NORTHEAST. EXPECT SHOWERS TO PERSIST IN THE AREA AS THIS SYSTEM
MOVES NORTHEAST. A BREAK IN THE PRECIPITATION CHANCES OCCURS
TOMORROW AS THIS SYSTEM MOVES OUT BEFORE THE NEXT SYSTEM
APPROACHES FROM THE CENTRAL ROCKIES AND PRECIP CHANCES INCREASE
FROM THE WEST WEDNESDAY NIGHT AND PERSIST INTO THE WEEKEND DUE TO
THE SLOW MOVEMENT OF THIS SYSTEM OVER THE PLAINS. IT WILL BE A WET
PATTERN IN GENERAL FOR A FEW DAYS... BUT THE SPECIFIC DAY-TO-DAY
POPS AND GEOGRAPHY ARE A STILL SOMEWHAT UNCERTAIN AND WILL DEPEND
ON THE PATH AND SPEED OF THIS SYSTEM.
&&
.PRELIMINARY POINT TEMPS/POPS...
OKLAHOMA CITY OK 59 49 73 56 / 70 30 10 20
HOBART OK 62 44 76 56 / 60 10 10 30
WICHITA FALLS TX 60 48 78 58 / 30 10 10 20
GAGE OK 68 43 75 51 / 10 10 10 30
PONCA CITY OK 62 47 71 54 / 70 30 10 20
DURANT OK 59 53 74 57 / 40 30 10 10
&&
.OUN WATCHES/WARNINGS/ADVISORIES...
OK...NONE.
TX...NONE.
&&
$$
17/25
AREA FORECAST DISCUSSION...UPDATED
NWS NORMAN OK
1112 AM CDT TUE APR 14 2015
.UPDATE...
ADJUSTED RAIN CHANCES THIS AFTERNOON TO LOWER THEM IN
WESTERN OKLAHOMA AND INCREASE THEM EAST OF I-40. ALSO...ADJUSTED
HIGHS UPWARDS IN NORTHWEST OKLAHOMA AND DOWNWARDS SOUTHEAST OF
I-44. DECREASED CLOUD COVER THIS AFTERNOON IN WESTERN OKLAHOMA.
&&
.DISCUSSION...
LIGHT RAIN WILL SLOWLY DECREASE IN COVERAGE THIS AFTERNOON AS
THE MID/UPPER LOW DEPARTS THE AREA.
LATEST RADARS INDICATED AREAS OF LIGHT RAIN/SPRINKLES MAINLY EAST
OF A CHEROKEE TO ALTUS TO CROWELL LINE. TWO AREAS OF HIGHER
COVERAGE EXISTED FROM NEAR PAULS VALLEY TO MCALESTER AND ANOTHER
AREA WAS EAST OF ENID TO PERRY TO JUST SOUTH OF PONCA CITY.
ADJUSTED RAIN CHANCES TO ACCOUNT FOR THESE AREAS. ADDITIONAL
RAINFALL TODAY MAY BE UP TO ONE HALF INCH IN THESE LOCATIONS.
STILL BELIEVE LIGHT RAIN COVERAGE WILL DECREASE THIS AFTERNOON IN
AGREEMENT WITH THE LATEST HRRR RUNS. THUS TWEAKED RAIN CHANCES
ACCORDINGLY. ADDITIONAL RAINFALL WILL ONLY BE A FEW HUNDREDTHS IN
MANY LOCATIONS. BELIEVE RAIN HAS ENDED WEST OF A CHEROKEE TO ALTUS
LINE.
CLOUD COVER AND RAIN WILL KEEP TEMPERATURES DOWN TODAY...
ESPECIALLY SOUTHEAST OF I-44 WHERE MOISTURE IS DEEPEST...SO
LOWERED TEMPERATURES. ON THE OTHER HAND...SOME CLEARING IS ALREADY
OCCURRING IN WESTERN OKLAHOMA...SO TEMPERATURES WERE INCREASED
THERE.
PRODUCTS HAVE BEEN UPDATED.
MBS
&&
.PREV DISCUSSION... /ISSUED 425 AM CDT TUE APR 14 2015/
DISCUSSION...
UPPER LOW OVER SOUTHWEST OKLAHOMA CONTINUES TO WADDLE SLOWLY
NORTHEAST. EXPECT SHOWERS TO PERSIST IN THE AREA AS THIS SYSTEM
MOVES NORTHEAST. A BREAK IN THE PRECIPITATION CHANCES OCCURS
TOMORROW AS THIS SYSTEM MOVES OUT BEFORE THE NEXT SYSTEM
APPROACHES FROM THE CENTRAL ROCKIES AND PRECIP CHANCES INCREASE
FROM THE WEST WEDNESDAY NIGHT AND PERSIST INTO THE WEEKEND DUE TO
THE SLOW MOVEMENT OF THIS SYSTEM OVER THE PLAINS. IT WILL BE A WET
PATTERN IN GENERAL FOR A FEW DAYS... BUT THE SPECIFIC DAY-TO-DAY
POPS AND GEOGRAPHY ARE A STILL SOMEWHAT UNCERTAIN AND WILL DEPEND
ON THE PATH AND SPEED OF THIS SYSTEM.
&&
.PRELIMINARY POINT TEMPS/POPS...
OKLAHOMA CITY OK 59 49 73 56 / 70 30 10 20
HOBART OK 62 44 76 56 / 60 10 10 30
WICHITA FALLS TX 60 48 78 58 / 30 10 10 20
GAGE OK 68 43 75 51 / 10 10 10 30
PONCA CITY OK 62 47 71 54 / 70 30 10 20
DURANT OK 59 53 74 57 / 40 30 10 10
&&
.OUN WATCHES/WARNINGS/ADVISORIES...
OK...NONE.
TX...NONE.
&&
$$
17/25
AREA FORECAST DISCUSSION
NWS MEDFORD OR
1042 PM PDT MON APR 13 2015
.UPDATED AVIATION DISCUSSION.
.DISCUSSION...A COLD FRONT IS MOVING THROUGH THE FORECAST
AREA...DROPPING TEMPERATURES BY 10 DEGREES IN LESS THAN AN HOUR AS
IT MOVES THROUGH. FEELING A SHARP TEMPERATURE CHANGE WITH A COLD
FRONT AS IT MOVES THROUGH IS NOT THAT COMMON IN THE VALLEYS OF
SOUTHERN OREGON OR NORTHERN CALIFORNIA...BUT TONIGHT`S FRONT WILL
DROP SNOW LEVELS SIGNIFICANTLY OVERNIGHT. BASED ON CURRENT
OBSERVATIONS AND THE NAM VERIFYING PRETTY WELL...HAVE BROUGHT
SNOW LEVELS DOWN TO NEAR 2000 FEET WEST OF THE CASCADES TONIGHT.
LATEST HRRR RUNS...IN COMBINATION WITH CURRENT SATELLITE
IMAGERY...ROAD SURFACE TEMPERATURES...AND METRO ROAD SURFACE
TEMPERATURE FORECASTS...SUGGEST THAT IMPACTS FROM THIS SNOWFALL
WILL BE MINIMAL. SOME SNOW WILL LIKELY FALL OVER SEXTON PASS AND
SISKIYOU SUMMIT ON INTERSTATE 5 THIS EVENING...BUT MOST SNOWFALL
SHOULD MELT ON THE ROADS AND LOWERED VISIBILITY SHOULD BE THE MOST
SIGNIFICANT IMPACT...SO DRIVERS SHOULD BE PREPARED AND OF COURSE
SLOW DOWN DURING ANY SNOW SHOWERS.
IN THE CASCADE PASSES...TEMPERATURES ARE JUST DROPPING TO FREEZING
AT DIAMOND LAKE WITH WET ROADS PER WEBCAMS. SIMILAR TO PREVIOUS
FORECAST THOUGHTS...LATEST MODELS SUGGEST A FEW INCHES OF
ACCUMULATION POSSIBLE AT AREAS LIKE DIAMOND LAKE...AND ROADS COULD
BECOME SLIPPERY LATER TONIGHT AS ROAD TEMPERATURES COOL TO NEAR
FREEZING. TRAVELERS SHOULD USE EXTRA CAUTION IF TRAVELING IN THE
CASCADES OVERNIGHT.
ADDITIONALLY...THE FRONT HAS BROUGHT GUSTY WINDS TO THE AREA...AND
HAVE ISSUED A WIND ADVISORY THROUGH THE EVENING FOR JACKSON COUNTY
WITH GUSTS TO 45 MPH.
LAST BUT NOT LEAST...GIVEN RECENT LIGHTNING STRIKES AND THE
PROGRESSION OF THE COLD POOL ALOFT...WE THINK OVERNIGHT THUNDERSTORMS
ARE POSSIBLE FROM GRANTS PASS NORTHWEST INTO JOSEPHINE...CURRY...COOS...AND
DOUGLAS COUNTIES.
SHOWERS ARE STILL POSSIBLE TOMORROW IN A WEAKLY UNSTABLE AIR MASS.
PLEASE SEE THE PREVIOUS DISCUSSION BELOW FOR DETAILS ON A RETURN
TO TO WARMER AND DRIER CONDITIONS LATER IN THE WEEK.
&&
.AVIATION...FOR THE 14/06Z TAF CYCLE...AN UNSTABLE AIR MASS WILL
MAINTAIN A MIX OF MVFR AND VFR CEILINGS IN SHOWERS OVERNIGHT.
THUNDERSTORMS ARE POSSIBLE LATE TONIGHT AND INTO THE EARLY MORNING
OVER PARTS OF COOS...CURRY...DOUGLAS...AND JOSEPHINE COUNTIES...WITH
THE BEST CHANCE AT THE IMMEDIATE COAST. THERE IS SOME UNCERTAINTY
WITH THE CLOUD DECKS TONIGHT WITH COLD SINKING AIR MOVING IN BEHIND
THE FRONT. MODELS AND OBSERVATIONS SUPPORT MAINTAINING MVFR
CONDITIONS FOR MUCH OF THE FORECAST AREA...SO HAVE KEPT THIS THEME
IN THE MOST RECENT TAFS.
MOUNTAIN OBSCURATION WILL AFFECT THE ENTIRE AREA THROUGH TUESDAY
MORNING...AND FREEZING LEVELS WILL CONTINUE TO FALL THROUGH THE
NIGHT. CONDITIONS SHOULD IMPROVE TO VFR AT MOST LOCATIONS BY LATE
TUESDAY MORNING OR EARLY AFTERNOON. SK
&&
.MARINE...UPDATED 900 PM PDT MONDAY APR 13 2015...WINDS HAVE
DECREASED TONIGHT TONIGHT...WELL BEHIND A COLD FRONT THAT MOVED
THROUGH EARLIER TODAY. THUNDERSTORMS ARE POSSIBLE THROUGH TUESDAY
MORNING AND STEEP SEAS AND SHOWERS WILL CONTINUE THROUGH TUESDAY. A
THERMAL TROUGH WILL DEVELOP WEDNESDAY AND THURSDAY WITH INCREASING
NORTH WINDS AND SEAS. THERE IS THE POTENTIAL FOR GALES SOUTH OF CAPE
BLANCO. THERE WAS SOME DISAGREEMENT WITH THE MODELS ON WINDS
WEDNESDAY EVENING SO STAYED AWAY FROM A GALE WATCH FOR WEDNESDAY
EVENING. THEN MODERATE WEST TO NORTHWEST SWELL WITH VERY LONG PERIOD
WILL ALSO ENTER THE REGION THURSDAY AND THEN LOWER ON FRIDAY. NORTH
WINDS MAY LOWER BRIEFLY ON FRIDAY BEFORE STRENGTHENING AGAIN THIS
WEEKEND. SK
&&
.PREV DISCUSSION... /ISSUED 522 PM PDT MON APR 13 2015/
SHORT TERM...TONIGHT THROUGH THURSDAY NIGHT.
THE MAIN ITEMS OF INTEREST IN THE SHORT TERM ARE GUSTY WINDS
TONIGHT (STRONGEST ON THE EAST SIDE), RAIN AND SNOW WITH FALLING
SNOW LEVELS TONIGHT, A SLIGHT CHANCE OF COASTAL THUNDERSTORMS
LATE THIS EVENING INTO EARLY TUESDAY MORNING, SHOWERS AND SNOW
SHOWERS LATE TONIGHT INTO TUESDAY EVENING, AND COLD MORNING LOW
TEMPERATURES.
THERE WAS LITTLE ADJUSTMENT NEEDED TO THE FORECAST FOR TONIGHT.
A FAST MOVING COLD FRONT IS NOW REACHING THE COAST. WESTERLY
WINDS THIS AFTERNOON HAVE INCREASED TO RIGHT AROUND THE EXPECTED
STRENGTH. THE 12Z GFS MOS WIND SPEEDS WERE FORECAST TO BE SLIGHTLY
STRONGER THAN THE NAM MOS, AND ARE VERIFYING WELL AT THIS TIME
WITH WIDESPREAD REPORTS OF GUSTY, BREEZY 15 TO 25 MPH
WINDS...INCLUDING GUSTS OF 43 MPH AT SUMMER LAKE.
SNOW LEVELS WILL DROP QUICKLY FROM AROUND 6000 TO 7000 FEET THIS
AFTERNOON TO AROUND 2500 TO 3000 FEET BY THE TIME PRECIPITATION
TAPERS TO LIGHT SHOWERS LATE TONIGHT. THE BULK OF COASTAL RAIN
WILL FALL FROM NOW THROUGH THE EARLY EVENING, MAINLY AN EVENING
EVENT FOR THE WEST SIDE, AND A LATE NIGHT EVENT FOR THE EAST SIDE.
SNOWFALL OF 2 TO 5 INCHES IS EXPECTED AROUND CRATER LAKE WITH 1 TO
2 INCHES FOR MUCH OF THE CASCADES, AND GENERALLY LESS THAN AN INCH
OF SNOW ON THE EAST SIDE.
THE SLIGHT CHANCE OF COASTAL THUNDERSTORMS WILL ARISE FROM A
POST-FRONTAL SURFACE TROUGH THAT WILL HAVE ITS LANDFALL COINCIDE
WITH THE AXIS OF THE UPPER LEVEL TROUGH/COLDEST AIR ALOFT MOVING
INLAND. I MENTIONED IT IN YESTERDAY`S DISCUSSION AND IT BEARS
REPEATING THAT THE WEATHER ON TUESDAY WILL HAVE A RESEMBLANCE TO
WHAT OCCURRED ON SATURDAY. A COLD, WEAKLY UNSTABLE NORTHWEST FLOW
ALOFT WILL PRODUCE SCATTERED TO NUMEROUS SHOWERS AND SNOW SHOWERS
THAT WILL FALL OUT OF LOW TOPPED CUMULUS CLOUDS. THE SNOW LEVEL ON
TUESDAY WILL RISE FROM AROUND 2500 FEET TO AROUND 3500 FEET WITH
AN ADDITIONAL INCH OF SNOW POSSIBLE IN THE CASCADES EXCEPT LIKELY
A BIT MORE (AROUND 2 INCHES) FOR CRATER LAKE.
VALLEY LOW CLOUDS AND PATCHY FOG ARE LIKELY TO HINDER COOLING
DURING EACH OF THE NEXT TWO NIGHTS, BUT IT WILL STILL BE QUITE
COLD ANYWAY WITH LOWS SEVERAL DEGREES BELOW NORMAL.
HIGH PRESSURE CENTERED OFFSHORE FROM CALIFORNIA WILL BUILD INTO
THE WEST COAST AND BRING A RETURN OF MOSTLY CLEAR TO CLEAR SKIES
WITH A WARMING TREND WEDNESDAY THROUGH THURSDAY.
LONG TERM...FRIDAY THROUGH MONDAY.
WARM AND DRY CONDITIONS WILL PERSIST THROUGH THE WEEKEND AS A
STRONG LONG WAVE RIDGE SETTLES JUST OFF THE WEST COAST WITH
NORTHERLY FLOW ALOFT AND LOW LEVEL OFFSHORE FLOW. A SHORT WAVE
TROUGH IS FORECAST TO MOVE ACROSS WASHINGTON AND NORTHERN OREGON
ON FRIDAY. THE MAIN EFFECT FROM THIS FEATURE IS TO PUSH HIGH
TEMPERATURES DOWN A FEW DEGREES ALTHOUGH IT WILL STILL BE ABOVE
SEASONAL NORMS. WE MAY ALSO SEE A SLIGHT INCREASE IN THE SURFACE
WESTERLY WINDS. THE GFS SHOWS SOME INSTABILITY IN TERMS OF THE
LIFTED INDEX BUT WESTERLY FLOW IS GENERALLY NOT FAVORABLE FOR
THUNDERSTORMS AND MOISTURE WILL BE VERY LIMITED.
ON SATURDAY THE LONG WAVE RIDGE REBUILDS WESTWARD TO AROUND
LONGITUDE 130W ALLOWING THE SHORT WAVE TROUGH TO DROP SOUTH ACROSS
OUR FORECAST AREA IN THE NORTH TO NORTHWEST FLOW ALOFT. THERE
SEEMS TO BE MORE INSTABILITY ACROSS OUR NORTHERN CALIFORNIA ZONE
SOUTHWARD. AT THIS POINT WE FEEL THAT THIS WOULD TRANSLATE INTO
MORE CUMULUS BUILDUPS OVER THE SISKIYOUS AND THE MARBLE MOUNTAINS
ON SATURDAY. THE RIDGE CONTINUES TO BUILD INTO THE WEST COAST
SUNDAY AND MONDAY. DURING THE PAST 10 RUNS THE GFS TREND HAS BEEN
TO FORECAST HIGHER 500 MB HEIGHT OVER THE PACIFIC NORTHWEST SO
CONFIDENCE IS HIGH THAT WE WILL SEE A WARM AND DRY TREND. HIGHS
IN THE ROGUE VALLEY ARE FORECAST TO BE IN THE LOWER 80S FROM
FRIDAY THROUGH MONDAY (WITH THE EXCEPTION OF SATURDAY DUE TO CLOUD
COVER). IF THIS SCENARIO HOLDS TRUE, THIS IS ALMOST 20 DEGREES
ABOVE SEASONAL NORMS FOR MID APRIL FOR THE ROGUE VALLEY AND ABOUT
15 DEGREES ABOVE NORMAL FOR AREAS EAST OF THE CASCADES. /FB
&&
.MFR WATCHES/WARNINGS/ADVISORIES...
OR...WIND ADVISORY UNTIL 11 PM PDT THIS EVENING FOR ORZ026-620>623.
CA...NONE.
PACIFIC COASTAL WATERS...SMALL CRAFT ADVISORY FOR WINDS UNTIL 8 PM PDT THIS EVENING FOR
PZZ350-356-370-376.
SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS UNTIL 11 AM PDT TUESDAY
FOR PZZ350-356.
SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS UNTIL 11 PM PDT TUESDAY
FOR PZZ370-376.
$$
NSK/FJB/MAS
AREA FORECAST DISCUSSION
NWS NASHVILLE TN
126 PM CDT TUE APR 14 2015
.UPDATE...
18Z TAF DISCUSSION.
&&
.AVIATION...
CURRENT VFR/MVFR CIGS TO BECOME IFR/MVFR LATE THIS
AFTERNOON/EVENING THEN LIFR/IFR OVERNIGHT AS NEXT WAVE OF -SHRA
SPREADS INTO THE MID STATE. EXPECT -SHRA TO REACH AIRPORTS AROUND
15/03-04Z PER HRRR WITH MVFR VIS. NORTH WINDS ANTICIPATED AT
CKV/BNA THROUGH THE TAF PERIOD...WHILE CURRENT SOUTHWEST WINDS AT
CSV BECOME NORTHWEST THEN NORTH AFTER FROPA AT 14/19Z.
SHAMBURGER
&&
.PREV DISCUSSION... /ISSUED 1017 AM CDT TUE APR 14 2015/
UPDATE...
MAIN AREA OF RAIN HAS PUSHED NORTH OF THE MID STATE INTO THE KENTUCKY
AT THIS HOUR WILL A FEW TRAILING SHOWERS DOWN INTO MIDDLE TENNESSEE
GENERALLY EAST OF INTERSTATE 65. 1015 MBAR SURFACE LOW CENTERED
BETWEEN NASHVILLE AND CROSSVILLE AT 14Z WITH FRONTAL BOUNDARY DRAPED
DOW THROUGH NORTHEAST MISSISSIPPI INTO ANOTHER LOW IN NORTHEAST
LOUISIANA. A LITTLE COOLER TEMPS FAR NORTHERN MIDDLE TENNESSEE
NORTHWARD. MODELS TAKE SURFACE LOW IN EASTERN MIDDLE TENNESSEE
TO THE EAST AND OFF THE PLATEAU THIS AFTERNOON. LOOKS LIKE THE
SURFACE BOUNDARY WILL REMAIN CLOSE TO OUR AREA NEXT 24 HOURS WITH
ANOTHER ORGANIZED ROUND OF RAIN COMING LATER TONIGHT AND ON
WEDNESDAY...ALTHOUGH MODELS TRY AND HOLD BULK OF THAT RAIN JUST TO
OUR SOUTH AND SHUNT IT OFF TOWARDS NORTH GEORGIA DURING THE DAY ON
WEDNESDAY...RAIN DOES LOOK LIKELY ON WEDNESDAY.
WATER VAPOR DOES SHOW SOME DRYING WORKING INTO THE AREA WHILE LAST
SEVERAL LAPS SOUNDINGS HAVE TRENDED TOWARDS DRYING ABOVE 700
MBARS. IF THIS TREND CONTINUES WE COULD SEE A FEW PEAKS OF SUN
BY AFTERNOON. HIGHS TODAY IN THE MID AND UPPER 60S NORTHWEST HALF
WITH LOWER 70S SOUTHEAST.
&&
.OHX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
55
AREA FORECAST DISCUSSION...UPDATED
NWS AMARILLO TX
1033 PM CDT WED APR 15 2015
.AVIATION...
THE BEST CHANCE FOR ANY SHOWERS AT DHT AND GUY MAY COME OVERNIGHT
TONIGHT AS A SURFACE TROUGH SLIDES INTO THESE AREAS. HAVE INSERTED
SOME SHOWERS LATE TONIGHT INTO EARLY THURSDAY MORNING FOR GUY AND
DHT...BUT KEPT CONDITIONS VFR. AT AMA...THINK ANY THREAT OF SHOWERS
OR THUNDERSTORMS WILL HOLD OFF UNTIL THURSDAY AFTERNOON. AND EVEN
THEN THEY COULD DEVELOP EAST OF AMA. SO FOR NOW HAVE NOT PUT ANY
THREAT OF THUNDERSTORMS IN AT AMA...BUT THEY WILL LIKELY NOT BE TOO
FAR AWAY.
WINDS WILL BE LIGHT NEAR THE SURFACE TROUGH AT DHT AND GUY THURSDAY
MORNING. BUT...SOUTHEAST WINDS SHOULD PICK UP AND GET GUSTY IN THESE
AREAS BY AFTERNOON. SOUTHEAST WINDS WILL INCREASE THROUGH THE MORNING
AT AMA.
&&
.PREV DISCUSSION... /ISSUED 633 PM CDT WED APR 15 2015/
AVIATION...
00Z TAFS...VFR CONDITIONS ARE EXPECTED OUTSIDE OF CONVECTION.
SCATTERED SHOWERS AND THUNDERSTORMS WILL CONTINUE THIS
EVENING...MAINLY OVER THE CENTRAL AND EASTERN PANHANDLES. ADDITIONAL
CONVECTION MAY DEVELOP DURING THE OVERNIGHT HOURS BUT COVERAGE SHOULD
BE SPOTTY. WINDS WILL INCREASE OUT OF THE SOUTH TO SOUTHEAST LATE
MORNING ON THURSDAY. HAVE INCLUDED PROB30 GROUPS FOR THUNDERSTORMS AT
ALL TAF SITES FOR THE EARLY AFTERNOON...WITH BETTER CHANCES LATER IN
THE DAY FOR STRONG TO SEVERE STORMS.
ELSENHEIMER
PREV DISCUSSION... /ISSUED 416 PM CDT WED APR 15 2015/
SHORT TERM...(THIS EVENING THROUGH THURSDAY NIGHT)
NO SURPRISE THE FOCUS OF THE FORECAST IS GOING TO BE CENTERED AROUND
THE CLOSED UPPER LEVEL LOW CURRENTLY SLIDING SOUTH ACROSS THE
UTAH/COLORADO STATE LINES.
THIS AFTERNOON/TONIGHT...A SURFACE TROUGH IS SLOWLY MOVING INTO THE
PANHANDLES THIS AFTERNOON AND IS EXPECTED TO HELP CONVECTION
DEVELOP. REGIONAL RADAR MOSAIC SHOWS THAT CONVECTION HAS ALREADY
BEGUN ACROSS THE SOUTH CENTRAL TEXAS PANHANDLE. RUC FORECAST MUCAPE
SHOWS THAT CONVECTION WILL HAVE MARGINAL INSTABILITY ON THE ORDER OF
500-100 J/KG MAINLY ACROSS THE CENTRAL AND NORTHEASTERN PANHANDLES
WHERE AS THE SOUTHEASTERN TEXAS PANHANDLES ARE FORECAST FOR
1000-1500 J/KG. A FEW STRONG TO SEVERE THUNDERSTORMS WILL BE
POSSIBLE THIS AFTERNOON GIVEN DEEP LAYER SHEAR WILL BE ROUGHLY 30KT.
THE PRIMARY HAZARDS WILL BE HAIL UP TO THE SIZE OF HALF DOLLARS AND
DAMAGING WIND GUSTS UP TO 60 MPH. CONVECTIVE CHANCES WILL LING
THROUGH THE OVERNIGHT HOURS AND INTO EARLY TOMORROW MORNING HOWEVER
THE SEVERE THREAT SHOULD DIMINISH BY 11 PM.
THURSDAY...A MORE FAVORABLE ENVIRONMENT FOR SEVERE WEATHER EXIST
ACROSS THE PANHANDLES ON THURSDAY. THE CLOSED LOW WILL BE WELL
ESTABLISHED OVER THE FOUR CORNERS REGION AND A VORT LOBE ROUNDING
THE LOW WILL GIVE A SLIGHT NEGATIVE TILT TO THE PATTERN. THE TIMING
OF THIS LOBE IS IN THE GENERAL TIMING OF PEAK HEATING WILL WILL GIVE
AMPLE SUPPORT OF CONVECTIVE DEVELOPMENT. SHORT RANGE MODELS ARE
HINTING AT AN EARLIER CONVECTIVE INITIATION ACROSS THE WESTERN
PANHANDLES BETWEEN 10AM AND NOON TOMORROW WHILE HOLDING OFF
SIGNIFICANT DEVELOPMENT UNTIL THE AFTERNOON HOURS. MODELS SHOW THAT
STORMS THAT DEVELOP DURING THE AFTERNOON HOURS WILL HAVE 1000-2000
J/KG TO WORK WITH AS DEEP LAYER SHEAR VALUES RANGE FROM 30KT TO
35KT. HODOGRAPHS SUPPORT DISCRETE SUPERCELL DEVELOPMENT BEFORE
CONGEALING INTO A LINEAR STRUCTURE DURING THE EVENING HOURS. PWATS
THURSDAY AFTERNOON ARE FORECAST TO RANGE BETWEEN 0.95 TO 1.05 INCHES
WHICH IS BETWEEN THE CLIMATOLOGICAL +2SD AND THE 99TH PERCENTILE FOR
MID APRIL. THIS AMPLE MOISTURE WILL SUPPORT THE POTENTIAL FOR STORMS
TO PRODUCE MODERATE TO HEAVY RAINFALL. LARGE HAIL AND DAMAGING WIND
WILL BE THE PRIMARY SEVERE WEATHER THREAT WITH AN ISOLATED TORNADO
OR TWO BEING POSSIBLE. CONVECTION WILL PUSH OFF INTO WESTERN
OKLAHOMA ROUGHLY AROUND 11 PM CDT.
14
LONG TERM...(FRIDAY THROUGH TUESDAY)
A FAIRLY PROGRESSIVE WEATHER PATTERN WILL CONTINUE FRIDAY AS THE
UPPER LOW SLOWLY BEGINS MOVING EAST. SINCE THE UPPER LOW WILL BE
SITUATED SLIGHTLY FURTHER TO THE EAST COMPARED TO ITS LOCATION ON
THURSDAY...AREA OF CONCERN FOR THUNDERSTORM DEVELOPMENT WILL BE
ACROSS THE EASTERN PANHANDLES ON FRIDAY. IN FACT...THE GFS SOLUTION
IS A LITTLE MORE PROGRESSIVE...SO MUCH OF THE FORECAST AREA ENDS UP
BEING DRY SLOTTED FRIDAY MAKING HIGH TEMPERATURES EVEN WARMER. SO
QUITE A BIT OF UNCERTAINTY EXISTS CURRENTLY FOR FRIDAY`S CHANCES FOR
STORMS. IF STORMS DO DEVELOP...THEY COULD EASILY BE STRONG TO SEVERE
WITH HAIL BEING THE BIGGEST THREAT.
BY SATURDAY...LOOKS LIKE THE UPPER LOW MOVES JUST NORTH OF THE
REGION...WITH ONLY AN ISOLATED CHANCE OF ANY CONVECTION DEVELOPING.
AS THIS UPPER LOW FINALLY MOVES WELL TO THE EAST...NORTHWEST FLOW
DEVELOPS ALOFT ON SUNDAY. THIS NORTHWEST FLOW WILL HOLD STRONG SUNDAY
THROUGH THE MIDDLE OF NEXT WEEK WHICH TRANSLATES TO OFF AND ON
PRECIPITATION CHANCES WITH HIGHS IN THE 60S AND LOWER 70S DURING THIS
TIME FRAME...QUITE AN UNUSUAL PATTERN FOR MID APRIL OVER THE
PANHANDLES. SEVERE WEATHER CHANCES DO NOT LOOK IMPRESSIVE WITH THIS
SET UP...IN FACT THINK THUNDERSTORM CHANCES MAY BE HARD TO COME BY AS
WELL. BEST CHANCES FOR RAIN WILL CORRESPOND WITH UPPER LEVEL IMPULSES
RIDING DOWN THE NORTHWEST FLOW...SO AT THIS POINT IT LOOKS LIKE BOTH
MONDAY EVENING AND TUESDAY EVENING SHAPE UP TO HAVE THE BEST RAIN
CHANCES.
KH
&&
.AMA WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
OK...NONE.
&&
$$
15/11
AREA FORECAST DISCUSSION
NWS AMARILLO TX
633 PM CDT WED APR 15 2015
.AVIATION...
00Z TAFS...VFR CONDITIONS ARE EXPECTED OUTSIDE OF CONVECTION.
SCATTERED SHOWERS AND THUNDERSTORMS WILL CONTINUE THIS
EVENING...MAINLY OVER THE CENTRAL AND EASTERN PANHANDLES. ADDITIONAL
CONVECTION MAY DEVELOP DURING THE OVERNIGHT HOURS BUT COVERAGE SHOULD
BE SPOTTY. WINDS WILL INCREASE OUT OF THE SOUTH TO SOUTHEAST LATE
MORNING ON THURSDAY. HAVE INCLUDED PROB30 GROUPS FOR THUNDERSTORMS AT
ALL TAF SITES FOR THE EARLY AFTERNOON...WITH BETTER CHANCES LATER IN
THE DAY FOR STRONG TO SEVERE STORMS.
ELSENHEIMER
&&
.PREV DISCUSSION... /ISSUED 416 PM CDT WED APR 15 2015/
SHORT TERM...(THIS EVENING THROUGH THURSDAY NIGHT)
NO SURPRISE THE FOCUS OF THE FORECAST IS GOING TO BE CENTERED AROUND
THE CLOSED UPPER LEVEL LOW CURRENTLY SLIDING SOUTH ACROSS THE
UTAH/COLORADO STATE LINES.
THIS AFTERNOON/TONIGHT...A SURFACE TROUGH IS SLOWLY MOVING INTO THE
PANHANDLES THIS AFTERNOON AND IS EXPECTED TO HELP CONVECTION
DEVELOP. REGIONAL RADAR MOSAIC SHOWS THAT CONVECTION HAS ALREADY
BEGUN ACROSS THE SOUTH CENTRAL TEXAS PANHANDLE. RUC FORECAST MUCAPE
SHOWS THAT CONVECTION WILL HAVE MARGINAL INSTABILITY ON THE ORDER OF
500-100 J/KG MAINLY ACROSS THE CENTRAL AND NORTHEASTERN PANHANDLES
WHERE AS THE SOUTHEASTERN TEXAS PANHANDLES ARE FORECAST FOR
1000-1500 J/KG. A FEW STRONG TO SEVERE THUNDERSTORMS WILL BE
POSSIBLE THIS AFTERNOON GIVEN DEEP LAYER SHEAR WILL BE ROUGHLY 30KT.
THE PRIMARY HAZARDS WILL BE HAIL UP TO THE SIZE OF HALF DOLLARS AND
DAMAGING WIND GUSTS UP TO 60 MPH. CONVECTIVE CHANCES WILL LING
THROUGH THE OVERNIGHT HOURS AND INTO EARLY TOMORROW MORNING HOWEVER
THE SEVERE THREAT SHOULD DIMINISH BY 11 PM.
THURSDAY...A MORE FAVORABLE ENVIRONMENT FOR SEVERE WEATHER EXIST
ACROSS THE PANHANDLES ON THURSDAY. THE CLOSED LOW WILL BE WELL
ESTABLISHED OVER THE FOUR CORNERS REGION AND A VORT LOBE ROUNDING
THE LOW WILL GIVE A SLIGHT NEGATIVE TILT TO THE PATTERN. THE TIMING
OF THIS LOBE IS IN THE GENERAL TIMING OF PEAK HEATING WILL WILL GIVE
AMPLE SUPPORT OF CONVECTIVE DEVELOPMENT. SHORT RANGE MODELS ARE
HINTING AT AN EARLIER CONVECTIVE INITIATION ACROSS THE WESTERN
PANHANDLES BETWEEN 10AM AND NOON TOMORROW WHILE HOLDING OFF
SIGNIFICANT DEVELOPMENT UNTIL THE AFTERNOON HOURS. MODELS SHOW THAT
STORMS THAT DEVELOP DURING THE AFTERNOON HOURS WILL HAVE 1000-2000
J/KG TO WORK WITH AS DEEP LAYER SHEAR VALUES RANGE FROM 30KT TO
35KT. HODOGRAPHS SUPPORT DISCRETE SUPERCELL DEVELOPMENT BEFORE
CONGEALING INTO A LINEAR STRUCTURE DURING THE EVENING HOURS. PWATS
THURSDAY AFTERNOON ARE FORECAST TO RANGE BETWEEN 0.95 TO 1.05 INCHES
WHICH IS BETWEEN THE CLIMATOLOGICAL +2SD AND THE 99TH PERCENTILE FOR
MID APRIL. THIS AMPLE MOISTURE WILL SUPPORT THE POTENTIAL FOR STORMS
TO PRODUCE MODERATE TO HEAVY RAINFALL. LARGE HAIL AND DAMAGING WIND
WILL BE THE PRIMARY SEVERE WEATHER THREAT WITH AN ISOLATED TORNADO
OR TWO BEING POSSIBLE. CONVECTION WILL PUSH OFF INTO WESTERN
OKLAHOMA ROUGHLY AROUND 11 PM CDT.
14
LONG TERM...(FRIDAY THROUGH TUESDAY)
A FAIRLY PROGRESSIVE WEATHER PATTERN WILL CONTINUE FRIDAY AS THE
UPPER LOW SLOWLY BEGINS MOVING EAST. SINCE THE UPPER LOW WILL BE
SITUATED SLIGHTLY FURTHER TO THE EAST COMPARED TO ITS LOCATION ON
THURSDAY...AREA OF CONCERN FOR THUNDERSTORM DEVELOPMENT WILL BE
ACROSS THE EASTERN PANHANDLES ON FRIDAY. IN FACT...THE GFS SOLUTION
IS A LITTLE MORE PROGRESSIVE...SO MUCH OF THE FORECAST AREA ENDS UP
BEING DRY SLOTTED FRIDAY MAKING HIGH TEMPERATURES EVEN WARMER. SO
QUITE A BIT OF UNCERTAINTY EXISTS CURRENTLY FOR FRIDAY`S CHANCES FOR
STORMS. IF STORMS DO DEVELOP...THEY COULD EASILY BE STRONG TO SEVERE
WITH HAIL BEING THE BIGGEST THREAT.
BY SATURDAY...LOOKS LIKE THE UPPER LOW MOVES JUST NORTH OF THE
REGION...WITH ONLY AN ISOLATED CHANCE OF ANY CONVECTION DEVELOPING.
AS THIS UPPER LOW FINALLY MOVES WELL TO THE EAST...NORTHWEST FLOW
DEVELOPS ALOFT ON SUNDAY. THIS NORTHWEST FLOW WILL HOLD STRONG SUNDAY
THROUGH THE MIDDLE OF NEXT WEEK WHICH TRANSLATES TO OFF AND ON
PRECIPITATION CHANCES WITH HIGHS IN THE 60S AND LOWER 70S DURING THIS
TIME FRAME...QUITE AN UNUSUAL PATTERN FOR MID APRIL OVER THE
PANHANDLES. SEVERE WEATHER CHANCES DO NOT LOOK IMPRESSIVE WITH THIS
SET UP...IN FACT THINK THUNDERSTORM CHANCES MAY BE HARD TO COME BY AS
WELL. BEST CHANCES FOR RAIN WILL CORRESPOND WITH UPPER LEVEL IMPULSES
RIDING DOWN THE NORTHWEST FLOW...SO AT THIS POINT IT LOOKS LIKE BOTH
MONDAY EVENING AND TUESDAY EVENING SHAPE UP TO HAVE THE BEST RAIN
CHANCES.
KH
&&
.AMA WATCHES/WARNINGS/ADVISORIES...
TX...RED FLAG WARNING UNTIL 9 PM CDT THIS EVENING FOR THE FOLLOWING
ZONES: DALLAM...HARTLEY.
OK...RED FLAG WARNING UNTIL 9 PM CDT THIS EVENING FOR THE FOLLOWING
ZONES: CIMARRON.
&&
$$
18/15
AREA FORECAST DISCUSSION
NWS CORPUS CHRISTI TX
344 PM CDT TUE APR 14 2015
.SHORT TERM (TONIGHT THROUGH WEDNESDAY NIGHT)...THE UPPER LOW HAS
LIFTED NEWD OVER THE SRN PLAINS (WATER VAPOR IMAGERY/STREAMLINE
DATA) LATE THIS AFTN...DECREASING SYNOPTIC SCALE LIFT OVER THE
CWA/MSA. LATEST MSAS SUGGEST A WEAK BOUNDARY SW-NE ACRS THE CWA.
LATEST LAPS ANALYSIS DEPICTS MAX CAPE VALUES NEAR 1000 J/KG OVER
PORTIONS OF THE ERN CWA. EARLIER RAP OUTPUT SUGGESTED MAX CAPE
VALUES AROUND 1500 J/KG THIS EVENING. ANTICIPATE AT LEAST ISOLD
CONVECTION THIS EVENING/EARLY TNGT OVER THE CWA OWING TO LIMITED
INSTABILITY/SFC FORCING. SREF PROBABILITIES SUGGEST AT LEAST
PATCHY FOG OVER PORTIONS OF THE CWA DRG THE 09-14Z WEDNESDAY
PERIOD. WEDNESDAY...THE GFS PROG THE LFQ OF AN UPPER JET STREAK
ENTERING THE CWA BY THE AFTN. EARLIER NAM DETERMINISTIC OUTPUT
DEPICTED 2000-3500 J/KG CAPE VALUES OVER THE CWA FOR THE AFTN
HOURS. ANTICIPATE ISOD/SCT CONVECTION OVER THE CWA/MSA OWING TO
INSTABILITY/WEAKENING SFC BOUNDARY/UPPER FORCING (HOWEVER MSTR
MAY BECOME A LIMITING FACTOR OVR THE NERN CWA AS PWAT VALUES MAY
FALL TO NEAR NORMAL DRG THE AFTN.) SOME STORMS MAY BECOME STG DRG
THE AFTN/EARLY EVENING. WEDNESDAY NIGHT...THE GFS DETERMINISTIC
MAINTAIN JET DYNAMICS OVER THE CWA WHICH MAY CONTRIBUTE TO
ADDITIONAL AT LEAST ISOLD CONVECTION.
&&
.LONG TERM (THURSDAY THROUGH TUESDAY)...ACTIVE WEATHER IS EXPECTED
EARLY IN THE PERIOD AS A VERY STRONG SUBTROPICAL JET REMAINS FOCUSED
ACRS THE AREA AND MSTR/INSTABILITY RETURN. BOTH THE GFS/EURO DEPICT
50+ MID LVL SPEED MAX IMPINGING ON THE AREA THU AFTN WITH STRONG
UPPER SUPPORT IN THE FRONT LEFT QUAD OF THE UPPER JET. MSTR RETURN
LOOKS ROBUST WITH 70+ DEWPOINTS SPREADING BACK OVER THE REGION. SO
THE SVR POTNL WILL HINGE ON TOUGH TO PREDICT MESOSCALE DETAILS
CONCERNING DEGREE OF INSOLATION AND ANY LINGERING BOUNDARIES ACRS
THE RGN. AT A MINIMUM THE SYNOPTIC SETUP IS SUPPORTIVE OF SEVERE
POTENTIAL AND CONDITIONALLY COULD SUPPORT A HIGHER END EVENT.
ENOUGH SHEAR LOOKS TO BE IN PLACE SO THAT ALL MODES OF SVR WX ARE
PSBL HWVR DAMAGING WINDS/HAIL FROM MULTICELL CLUSTERS/BOWS LOOKS
MOST LIKELY. FRIDAY LOOKS POTENTIALLY ACTIVE AS WELL BUT AGAIN THE
EVOLUTION OF EARLIER CONVECTION WILL HAVE A HUGE IMPACT ON HOW
THINGS UNFOLD. AS FAR AS EXCESSIVE RAINS GO...VERY HEAVY PCPN
OVERNIGHT...4-6 INCHES IN SPOTS...HAS INCREASED OUR FLOOD THREAT
QUITE A BIT. DEEP CONVECTION COULD QUICKLY LEAD TO ADDITIONAL
FLOODING THU AND ESPLY FRI WHEN PWATS APPRCH 2 INCHES ON THE LATEST
MODELS. WILL ISSUE SPS TO ADDRESS SVR/+RA THREATS DURING THE LATE
WEEK PERIOD.
WILL LEAN TWRD SLOWER FROPA DEPICTED BY THE EURO AND KEEP POPS GOING
THRU MOST OF THE WEEKEND. AGAIN SOME POTENTIAL REMAINS FOR STRONG
STORMS AND HEAVY RAINS ON SAT. DRIER AIR SHOULD WIN OUT BY SUNDAY
AS UPPER LOW FINALLY PULLS EAST. NO MAJOR CHANGES TO PREV TEMP
FCSTS WERE MADE - GENERALLY LEANED TWRD THE COOLER HPC NUMBERS VS
THE WARMER MEX WITH THE CLOUD/PCPN.
&&
.PRELIMINARY POINT TEMPS/POPS...
CORPUS CHRISTI 67 81 70 80 71 / 30 30 20 50 40
VICTORIA 63 81 67 78 68 / 30 30 20 60 40
LAREDO 63 85 69 86 70 / 20 20 20 40 30
ALICE 65 84 68 83 70 / 30 30 20 50 40
ROCKPORT 68 78 70 76 71 / 30 30 20 60 40
COTULLA 62 84 67 82 68 / 20 20 20 40 30
KINGSVILLE 66 84 69 82 71 / 30 30 20 40 30
NAVY CORPUS 68 78 70 77 71 / 30 30 20 50 40
&&
.CRP WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
GM...NONE.
&&
$$
WC/87...SHORT TERM
TJ/70...LONG TERM
AREA FORECAST DISCUSSION
NWS SAN ANGELO TX
1147 PM CDT Mon Apr 13 2015
.AVIATION...
/06Z TAFS/
MVFR ceilings have already spread south into the KABI (Abilene) and
KSJT (San Angelo) terminals late this evening, and should spread
south through the remainder of the sites during the early morning
hours. With a cool and moist air mass behind a cold front, these
low clouds should persist through the morning hours on Tuesday,
before lifting to VFR for the afternoon.
&&
.PREV DISCUSSION... /ISSUED 949 PM CDT Mon Apr 13 2015/
UPDATE...
The cold front has moved south to the I-10 corridor, masked
somewhat by convective outflow from this evening`s thunderstorms.
Winds have shifted to the northeast at 5 to 15 mph and will remain
so overnight. Dewpoints have already fallen into the 40s across
western north TX and this drier air will advect into the region
tonight, limiting the potential for additional measurable
precipitation. However, PoPs were maintained areawide given the
presence of the cold core of the upper cyclone moving slowly
across the CWA through early Tuesday. Rain chances were trimmed
back Tuesday, with most areas expected to remain dry. Expect high
temperatures in the upper 60s to lower 70s with northwest winds
around 10 mph.
The Flash Flood and Severe Thunderstorm Watches were dropped as
conditions are no longer favorable for significant convection.
Johnson
PREV DISCUSSION... /ISSUED 636 PM CDT Mon Apr 13 2015/
AVIATION...
/00Z TAFS/
Showers and thunderstorms will affect the KABI and KSJT terminals
this evening. The storms were developing along and behind a Cold
front that extended from just north of San Angelo and Brady. Winds
will shift to the north just after 00Z at KSJT and KBBD as the
front moves through. MVFR ceilings will develop a couple hours after
frontal passage. The front should move through KSOA and KJCT
around 4Z. MVFR ceilings should rise to IFR Tuesday noon over most
sites.
PREV DISCUSSION... /ISSUED 416 PM CDT Mon Apr 13 2015/
UPDATE...
Added a flash flood watch through 1 AM CDT for portions of the Big
Country...Concho Valley and Heartland until 1 AM CDT. Slow moving
thunderstorms along and north of a cold front will produce quick
heavy rainfall amounts of 1 to 3 inches...and may result in flash
flooding.
PREV DISCUSSION... /ISSUED 353 PM CDT Mon Apr 13 2015/
SHORT TERM...
(Tonight and Tuesday)
Scattered showers and thunderstorms were developing along and north
of a cold front from Mertzon to San Angelo to Brownwood at 3 PM.
SPC RAP analysis indicated SB CAPES around 1000 J/KG in this
area...which is a slight risk for severe thunderstorms this
afternoon and evening. The slight risk extends to the I-20 corridor.
While the severe threat is large hail and damaging winds are the
main threats, slow moving thunderstorms focused along the front will
also bring the potential for localized heavy rainfall and flash
flooding. If storm coverage becomes widespread, a flash flood watch
may be needed for Concho Valley to Brownwood and northward to the
I-20 corridor. With an upper low to the northwest in the South
Plains, there is also a low potential for a land spout or brief
tornado. The heavy rain and severe weather threat will diminish a
couple hours after sunset.
The front is indicated to move south to I-10 by midnight. Included a
slight chance of showers or thunderstorms for southern areas, but
severe weather threat is minimal as the front moves into more stable
air.
Keeping a slight chance of showers and thunderstorms, along and
northwest of a Sweetwater to Junction line...but most of the
moisture and instability will be southeast of West Central Texas.
LONG TERM...
(Tuesday night through next Monday)
Dry and warmer conditions are expected Wednesday, as south winds
develop. An upper low will drop southeast into the Central Rockies.
The 12Z GFS and ECMWF differ on the track of this low, and this will
have implications on our rain chances Thursday into the weekend. The
ECMWF is slower and takes the upper low south into New Mexico Friday
and Friday night, then eventually opens the low and tracks the wave
east into Oklahoma Saturday night and Sunday. The GFS has an
elongated trough extending south from the low, and has the low
dropping southeast into the Red River Valley Friday night into
Saturday.
With enough moisture return/availability indicated, we have chance
PoPs for showers and thunderstorms beginning Wednesday night in the
west, and continuing Thursday through late Saturday. A cold frontal
passage is anticipated Thursday night into Friday, but have
uncertainty on the timing with the aforementioned model differences.
Will have to monitor the forecast setup for the potential of strong
to severe storms.
The forecast looks dry Sunday into the first part of next week with
temperatures close to normal.
&&
.PRELIMINARY POINT TEMPS/POPS...
Abilene 50 64 50 82 62 / 40 20 10 10 20
San Angelo 52 70 52 84 62 / 20 10 10 10 20
Junction 55 73 54 84 63 / 20 20 10 10 20
&&
.SJT WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
07
AREA FORECAST DISCUSSION
NWS BLACKSBURG VA
414 PM EDT TUE APR 14 2015
.SYNOPSIS...
A COLD FRONT WILL PUSH SOUTHEAST THROUGH THE AREA THIS EVENING. A
STRONG WEDGE OF HIGH PRESSURE WILL COVER THE REGION WEDNESDAY
THROUGH FRIDAY. ANOTHER COLD FRONT CROSS THE AREA OVER THE
WEEKEND.
&&
.NEAR TERM /THROUGH WEDNESDAY/...
AS OF 400 PM EDT TUESDAY...
MSAS ANALYSIS SHOWERS SURFACE LOW IN EXTREME SOUTHWEST VIRGINIA
ALONG A FRONT FROM SOUTHERN MARYLAND TO NORTHERN LOUISIANA.
SOUTH OF THIS BOUNDARY LIFTED INDEX VALUES WERE DOWN TO -4 WITH
CAPES IN THAT AIR MASS UP TO 1600 J/KG. THE FRONT WILL MOVE SOUTH
AS THE LOW MOVES EAST. SHORT RANGE MODELS HAD THE FRONT SOUTH OF
THE FORECAST AREA BY 02Z/10PM. HAVE SHOWERS WITH ISOLATED THUNDER
IN THE FORECAST UNTIL THE FRONT CLEARS THE SOUTHERN COUNTIES. IN
THE STABLE AIR NORTH OF THE FRONT...COVERAGE OF LIGHT RAIN WILL BE
DIMINISHING BUT UPSLOPE WILL CONTINUE WITH WIDESPREAD LOW
CLOUDS...FOG AND DRIZZLE. TEMPERATURES WILL DROP MORE NORTH OF THE
FRONT OVERNIGHT. GUIDANCE SUGGESTED THAT AS THE WEDGE CONTINUES TO
DEVELOP ON WEDNESDAY....TEMPERATURES WILL BE STEADY OR SLOWLY FALL
DURING THE DAY. USED A NON DIURNAL TEMPERATURE TREND FOR
WEDNESDAY.
&&
.SHORT TERM /WEDNESDAY NIGHT THROUGH FRIDAY NIGHT/...
AS OF 230 PM EDT TUESDAY...
AN AREA OF HIGH PRESSURE WILL WEDGE DOWN THE EAST COAST LATE
WEDNESDAY AND WILL LIKELY REMAIN IN THE REGION THROUGH THE PERIOD.
RAIN CHANCES INCREASE WEDNESDAY NIGHT AS OVERRUNNING MOISTURE IS
PUSHED OVER THE WEDGE FROM A DISTURBANCE TRACKING OVER THE OHIO
VALLEY AND ITS ASSOCIATED WARM FRONT MOVING NORTH OVER THE SOUTH-
CENTRAL APPALACHIANS. MODELS ARE DISPLAYING A SURFACE REFLECTIONS
OFF THE SOUTHEAST COAST...WHICH WILL LIKELY GENERATE CONVECTION
OFFSHORE AND LIMIT RAINFALL AMOUNTS OVER THE IMMEDIATE AREA
THURSDAY. SURFACE HIGH DRIFTS OFF THE NORTHEAST COAST WHILE THE
COASTAL REFLECTION INTENSIFIES INTO A SURFACE LOW. THE PRESSURE
GRADIENT BETWEEN THESE TWO FEATURES WILL BRING A STRONG FETCH OF
ATLANTIC MOISTURE TOWARDS THE SOUTH-CENTRAL APPALACHIANS. THE
LATEST 12Z MODELS HAVE THIS FETCH DIRECTED AT THE SOUTHWEST
VIRGINIA BLUE RIDGE. THIS MODEL FETCH OF MOISTURE WILL NEED TO BE
WATCHED ESPECIALLY IF WE REMAIN IN A WET WEATHER PATTERN THROUGH
MOST OF THE WEEK. ON FRIDAY...THE COASTAL LOW WILL KEEP CONVECTION
OFFSHORE WHILE WEAK HIGH PRESSURE DRIFTS OVER THE REGION. WEDGE
INFLUENCE LOOK TO REMAIN WITH GRAY CONDITIONS PERSISTING INTO
FRIDAY NIGHT. NOT RULING OUT ANY SUN BUT WITH A WEDGE...EASTERLY
FLOW AND MOSTLY CLOUDY SKIES...TEMPERATURES WILL BE ON THE COOL
SIDE THURSDAY AND FRIDAY.
&&
.LONG TERM /SATURDAY THROUGH TUESDAY/...
AS OF 245 PM EDT TUESDAY...
A COLD FRONT IS EXPECTED TO STALL ACROSS THE OHIO VALLEY ON SATURDAY
WITH A POSSIBLE CLOSED LOW HOVERING OVER THE OZARKS. THERE WILL
REMAIN A GOOD FLOW OF MOISTURE INTO THE REGION FROM THE GULF THROUGH
THE WEEKEND TO KEEP HIGH CHANCE TO LIKELY POPS. THE MAIN QUESTION
REGARDING RAIN IS TIMING. HIGH PRESSURE DRIFTS OVER THE REGION EARLY
NEXT WEEK TO BRING AN END TO THE RAIN. WITH MORE CLOUDS AND RAIN IN
THE FORECAST...TEMPERATURES WILL BE COOL BUT NOT TO FAR REMOVED FROM
NORMAL.
&&
.AVIATION /20Z TUESDAY THROUGH SUNDAY/...
AS OF 145 PM EDT TUESDAY...
LOW PRESSURE WAS OVER NORTHEAST TENNESSEE ALONG A COLD FRONT THAT
EXTENDED INTO THE DELMARVA. THE FRONT WILL MOVE SOUTH THIS
AFTERNOON AND EVENING AS THE LOW MOVES EAST. THIS WILL BRING THE
WINDS AROUND TO THE NORTHEAST TO NORTH. SOME WIND GUST UP TO 25
KNOTS ARE POSSIBLE BEFORE 00Z/8PM.
A LARGE AREA OF LIGHT TO MODERATE RAIN WITH MVFR VISIBILITIES AND
IFR CEILINGS ASSOCIATED WITH THE LOW WILL ALSO MOVE EAST. BASED
ON RADAR TRENDS AND HRRR GUIDANCE...THE BACK EDGE OF THE RAIN WILL
MOVER NORTHEAST OF THE FORECAST AREA BY 23Z/7PM. AS WEDGE BUILDS
INTO THE REGION...CEILINGS WILL REMAIN MAINLY IFR TO LIFR WITH
EAST TO NORTHEAST UPSLOPE WINDS. HIGH CONFIDENCE THAT THERE WILL
BE LITTLE IMPROVEMENT THROUGH 12Z/8AM. AREAS OF FOG AND DRIZZLE
ARE LIKELY. AFTER SUNRISE...CEILINGS AND FOG MAY LIFT TO MVFR
LEVELS.
EXTENDED AVIATION...
THE WEDGE REMAINS IN PLACE THROUGH AT LEAST FRIDAY MORNING.
EXPECTING A PROLONGED PERIOD OF IFR TO MVFR CEILINGS.
ON FRIDAY...LOW LEVEL FLOW TURNS TO THE SOUTHWEST IN ADVANCE OF A
COLD FRONT. ISOLATED TO SCATTERED SHOWERS AND THUNDERSTORMS ARE
POSSIBLE IN THE AFTERNOON...ESPECIALLY ONCE THE WEDGE BREAKS.
ON SATURDAY THE FRONT COMES THROUGH SHOWERS AND THUNDERSTORMS.
EXPECTING OCCASIONAL PERIODS OF MVFR CONDITIONS UNTIL THE FRONT
PASSES.
SUNDAY A DRIER AIR MASS WILL PUSH INTO THE REGION ALONG WITH HIGH
PRESSURE BEHIND THE FRONT. THIS IS A SLOWER TIMING THAN THE PAST
FEW RUNS OF THE MODELS. ONCE THIS DRIER AIR ARRIVES...CONDITIONS
SHOULD IMPROVE BACK TO VFR.
&&
.HYDROLOGY...
AS OF 410 PM EDT TUESDAY...
THE SOUTHWEST EDGE OF THE MODERATE PRECIPITATION HAD BEEN MOVING
NORTHEAST THROUGH THE FORECAST AREA IN ASSOCIATION WITH THE SHORT
WAVE OVER SOUTHWEST VIRGINIA AT 20Z/4PM. EXPECT THE SURFACE LOW
ALONG THE FRONT AND THE BOUNDARY TO CLEAR THE FORECAST AREA BY
10PM. THE AIR MASS SOUTH OF THE FRONT LATE THIS AFTERNOON AND
EVENING WILL BE JUST UNSTABLE ENOUGH TO SUPPORT ISOLATED
THUNDERSTORMS WHICH WILL MEAN HIGHER RAINFALL RATES. ONCE THE
FRONT AND SHORT WAVE CLEAR THE AREA...EXPECTED RAINFALL AMOUNTS
WILL DROP.
NO CHANGES TO THE WATCH ARE PLANNED AT THIS TIME.
A NEW FORECAST HAS BEEN ISSUED BY OHIO RIVER FORECAST CENTER FOR
THE GREENBRIER RIVER. THIS LATEST FORECAST BRINGS THE GREENBRIER
RIVER AT ALDERSON INTO ACTION STAGE LATE THIS EVENING.
&&
.RNK WATCHES/WARNINGS/ADVISORIES...
VA...FLOOD WATCH UNTIL 8 PM EDT THIS EVENING FOR VAZ007-010-011-
018>020.
FLOOD WATCH UNTIL MIDNIGHT EDT TONIGHT FOR VAZ009-012-013-015-
016.
NC...FLOOD WATCH UNTIL MIDNIGHT EDT TONIGHT FOR NCZ001>003-018>020.
WV...FLOOD WATCH UNTIL 8 PM EDT THIS EVENING FOR WVZ042>044-507-508.
&&
$$
SYNOPSIS...AMS
NEAR TERM...AMS
SHORT TERM...RCS
LONG TERM...RCS
AVIATION...AMS/JH
HYDROLOGY...AMS
AREA FORECAST DISCUSSION
NWS BLACKSBURG VA
205 PM EDT TUE APR 14 2015
.SYNOPSIS...
A COLD FRONT WILL SLIDE SOUTHEAST INTO THE AREA TODAY BEFORE
DROPPING SOUTH INTO THE CAROLINAS TONIGHT. A WEDGE OF HIGH
PRESSURE WILL BUILD IN BEHIND THE FRONT BY WEDNESDAY...AND LINGER
OVER THE REGION INTO AT LEAST FRIDAY. ANOTHER COLD FRONT WILL MOVE
ACROSS THE AREA OVER THE WEEKEND.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 230 AM EDT TUESDAY...
FORECAST REMAINS QUITE COMPLICATED GIVEN THE SLOW MOVING COLD FRONT TO
THE WEST AND ASSOCIATED WEAK LOW PRESSURE THAT WILL SCOOT OUT OF THE TN
VALLEY AND INTO THE REGION LATER TODAY. THIS JUST AS THE FRONT FOLDS IN
FROM THE NORTH/NW ALLOWING LOW LEVEL CONVERGENCE TO MAXIMIZE THIS
MORNING INTO LATE AFTERNOON. MODELS HAVE AGAIN TRENDED FARTHER NORTH
WITH THE MAIN BAROCLINIC ZONE WHICH HAS SHIFTED THE AXIS OF BEST UPPER
DIFFLUENCE AND CORRESPONDING LIFT FARTHER NORTH/WEST. THIS WHILE
ALLOWING LESS UPSLOPE GIVEN VEERING FLOW FROM SOUTH/SE TO MORE SW AHEAD
OF THE BOUNDARY TODAY. CONSENSUS APPEARS FOR A STRIP OF HIGHER QPF FROM
SE WEST VA EAST INTO THE VA HIGHLANDS AND POINTS EAST WITH A SHARP
GRADIENT LIKELY NEAR HIGHWAY 460 AND POINTS SOUTH WHERE WILL SEE
MORE SCATTERED COVERAGE IN COMPARISON TO THE WIDESPREAD/HEAVIER
SHRA UP NORTH. HOWEVER WHERE TO DRAW THE LINE QUITE IFFY GIVEN
LIKELY TREND OF THINGS BEING OVERALL SLOWER PER THE WAVE TRACKING
NEAR BRISTOL THIS AFTERNOON BEFORE SHUNTING EAST/SE. THIS MAY
ALLOW MUCH MORE OF A DIFFERENTIAL HEATING ZONE OVER THE SOUTH
WHERE THE LATEST NAM HAS CAPES NEAR 1K J/KG ALONG THE VA/NC BORDER
PENDING MORE BREAKS AND SUBSEQUENT HEATING. SPEED MAX TRACKING
ACROSS LATE MAY ALSO SPARK CLUSTERS OF TSRA THAT COULD LINE UP
BEFORE SPILLING SOUTH. THUS BEEFING UP THUNDER MENTION SOUTH AND
INCLUDING IN THE HWO PER DAY1 MARGINAL OUTLOOK.
OTRW HAVE ADJUSTED POPS DOWN SOME TO INIT EARLY ON...WITH HIGHER CAT
POPS NORTH/WEST FOR MUCH OF THE DAY...AND SLOWLY INCREASING FROM NORTH
TO SOUTH AS THE FRONT SAGS SOUTH AND THE WAVE HEADS EAST SIMILAR TO THE
NAM. FORECAST QPF OF 1-3 INCHES ESPCLY NW PROMPTS THE NEED TO EXTEND
THE FLOOD WATCH INTO THE VA HIGHLANDS GIVEN LOW FFG AND PERHAPS FARTHER
EAST LATER PENDING TRENDS. LONGER PERIOD OF WARM ADVECTION BEFORE THE
FLOW TURNS NE...AND POSSIBLY SOME SUN SOUTH SUGGESTS HIGHS WARMER
THAN PREVIOUS WITH MOST IN THE 60S TO LOWER 70S...AND SOME MID OR
EVEN UPPER 70S POSSIBLE FAR SOUTH IF THINGS BREAK OPEN MORE.
WAVE HEADS EAST THIS EVENING ALLOWING THE SURFACE FRONT TO BOW THROUGH
THE REGION FROM THE NORTH BRINGING THE ONSET OF THE LOW LEVEL WEDGE
FROM NE TO SW OVERNIGHT. THIS SHOULD TAKE THE DEFORMATION TYPE ZONE OF
HEAVIER SHRA TO THE EAST BY MIDNIGHT WITH RESIDUAL LEFTOVER MOISTURE
MAKING FOR CONTINUED SPOTTY -RA ESPCLY SW WHERE WILL SEE A WEAK
INVERTED TROUGH DEVELOP UNDER THE EASTERLY FLOW. THUS AFTER MOSTLY
LIKELY POPS DURING THE EARLY EVENING WILL SHIFT TO A MORE CHANCE REGIME
FOR -RA AND EVEN SOME SPOTTY -DZ AS THE NIGHT WEARS ON GIVEN THE
DECREASING DEPTH TO THE MOISTURE OFF FORECAST RAOBS LATE. KEPT TEMPS
SIMILAR TO THE SLIGHTLY WARMER MET MOS PER EXPECTED SLOWER TRENDS WITH
THE DEVELOPING CAD.
&&
.SHORT TERM /WEDNESDAY THROUGH THURSDAY NIGHT/...
AS OF 315 AM EDT TUESDAY...
EXPECTING THAT CONVECTION WILL DRIVE SFC COLD FRONT SOUTH OF US
BY WEDNESDAY MORNING ACROSS THE CAROLINAS. MAIN SHORTWAVE AND
ASSOCIATED LOW PRESSURE ALONG THE FRONT WILL BE OFFSHORE IN THE
ATLANTIC OCEAN. IN SITU CAD EVENT WILL BECOME WELL ESTABLISHED ON
WEDNESDAY. WITH CLOUDS AND RAIN...LOWERED HIGH TEMPERATURES FOR
WEDNESDAY. HIGHS FOR WEDNESDAY WILL BE BELOW NORMAL WITH READINGS
FROM AROUND 50 DEGREES IN THE MOUNTAINS TO NEAR 60 DEGREES IN THE
PIEDMONT. IN GENERAL...LEANED POPS TOWARDS THE NAM FOR WEDNESDAY AND
SHAPED OUR QPF TOWARDS HPC.
CLOUDY WITH AREAS OF RAIN AND FOG ARE ANTICIPATED WEDNESDAY NIGHT
INTO THURSDAY. PLACED HIGH POPS ACROSS THE SOUTH WHERE WEDGE UPGLIDE
OVERLAPS WITH SOME UPPER DIVERGENCE. LOW TEMPERATURES WEDNESDAY
NIGHT WILL RANGE FROM THE UPPER 30S IN THE MOUNTAINS TO THE LOWER
40S IN THE PIEDMONT. UNDERCUT MOS HIGH TEMPERATURES FOR THURSDAY
WITH PLENTY OF CLOUDS AND AREAS OF RAIN AND FOG UNDER CAD. HIGHS
WILL VARY FROM THE UPPER 40S IN THE NORTHWEST TO THE MID 50S IN THE
SOUTHEAST. THE CLOUDY DREARY WEATHER CONTINUES THURSDAY NIGHT INTO
FRIDAY WITH LOW TEMPERATURES GENERALLY FROM THE LOWER 40S IN THE
NORTHWEST MOUNTAINS TO THE LOWER 50S IN THE PIEDMONT.
&&
.LONG TERM /FRIDAY THROUGH MONDAY/...
AS OF 215 PM EDT MONDAY...
NORTHERN STREAM TROF OVER THE NORTHEAST AMPLIFIES WITH A SURFACE
COLD FRONT COMING THROUGH THE REGION ON SATURDAY. MEANWHILE A LOW IS
CLOSED OFF OVER THE ROCKIES ON FRIDAY.
CLOSED LOW OVER THE ROCKIES OPENS UP AND ALSO TRACKS INTO THE UPPER
MISSISSIPPI VALLEY SATURDAY AND SUNDAY...WITH A PIECE OF THIS SYSTEM
REACHING THE FORECAST AREA ON MONDAY. SURFACE HIGH PRESSURE CROSSES
THE NORTHEAST UNITED STATES SUNDAY THEN BY MONDAY...ALREADY BACK IN
YET ANOTHER WEDGE WITH DEEP SOUTHEAST UPSLOPE FLOW WITH STRONG 850
WINDS.
WILL KEEP SATURDAY NIGHT THROUGH SUNDAY NIGHT DRY. WEDGE MAY BE SLOW
TO BREAK ON FRIDAY WHICH MAY LIMIT MAXIMUM TEMPERATURES. BUT
SATURDAY AHEAD OF THE FRONT WILL BE MILDER. TEMPERATURES BEHIND THE
FRONT ON SUNDAY WILL BE AROUND NORMAL.
&&
.AVIATION /18Z TUESDAY THROUGH SUNDAY/...
AS OF 145 PM EDT TUESDAY...
LOW PRESSURE WAS OVER NORTHEAST TENNESSEE ALONG A COLD FRONT THAT
EXTENDED INTO THE DELMARVA. THE FRONT WILL MOVE SOUTH THIS
AFTERNOON AND EVENING AS THE LOW MOVES EAST. THIS WILL BRING THE
WINDS AROUND TO THE NORTHEAST TO NORTH. SOME WIND GUST UP TO 25
KNOTS ARE POSSIBLE BEFORE 00Z/8PM.
A LARGE AREA OF LIGHT TO MODERATE RAIN WITH MVFR VISIBILITIES AND
IFR CEILINGS ASSOCIATED WITH THE LOW WILL ALSO MOVE EAST. BASED
ON RADAR TRENDS AND HRRR GUIDANCE...THE BACK EDGE OF THE RAIN WILL
MOVER NORTHEAST OF THE FORECAST AREA BY 23Z/7PM. AS WEDGE BUILDS
INTO THE REGION...CEILINGS WILL REMAIN MAINLY IFR TO LIFR WITH
EAST TO NORTHEAST UPSLOPE WINDS. HIGH CONFIDENCE THAT THERE WILL
BE LITTLE IMPROVEMENT THROUGH 12Z/8AM. AREAS OF FOG AND DRIZZLE
ARE LIKELY. AFTER SUNRISE...CEILINGS AND FOG MAY LIFT TO MVFR
LEVELS.
EXTENDED AVIATION...
THE WEDGE REMAINS IN PLACE THROUGH AT LEAST FRIDAY MORNING.
EXPECTING A PROLONGED PERIOD OF IFR TO MVFR CEILINGS.
ON FRIDAY...LOW LEVEL FLOW TURNS TO THE SOUTHWEST IN ADVANCE OF A
COLD FRONT. ISOLATED TO SCATTERED SHOWERS AND THUNDERSTORMS ARE
POSSIBLE IN THE AFTERNOON...ESPECIALLY ONCE THE WEDGE BREAKS.
ON SATURDAY THE FRONT COMES THROUGH SHOWERS AND THUNDERSTORMS.
EXPECTING OCCASIONAL PERIODS OF MVFR CONDITIONS UNTIL THE FRONT
PASSES.
SUNDAY A DRIER AIR MASS WILL PUSH INTO THE REGION ALONG WITH HIGH
PRESSURE BEHIND THE FRONT. THIS IS A SLOWER TIMING THAN THE PAST
FEW RUNS OF THE MODELS. ONCE THIS DRIER AIR ARRIVES...CONDITIONS
SHOULD IMPROVE BACK TO VFR.
&&
.HYDROLOGY...
AS OF 330 AM EDT TUESDAY...
SHOWERS REMAIN SCATTERED ACROSS THE REGION EARLY THIS MORNING WITH
THE FRONT STILL WELL TO THE NW AND LOW PRESSURE OVER THE TN
VALLEY. LATEST HRRR SHOWS A SLOW FILLING IN OF PRECIP THROUGH THE
MORNING WITH THE MOST WIDESPREAD COVERAGE ESPCLY NORTHERN HALF
FROM MIDDAY THROUGH LATE AFTERNOON.
EXPECTED RAINFALL FOR MUCH OF THE FORECAST AREA WILL BE ONE TO TWO
INCHES EARLY WEDNESDAY. HOWEVER MODELS HAVE SHIFTED THE HEAVIER
AXIS OF PROJECTED RAINFALL NORTH ACROSS PARTS OF SOUTHEAST WEST
VIRGINIA INTO THE VIRGINIA HIGHLANDS WHERE POTENTIAL FOR TWO TO
THREE INCHES LOOKS POSSIBLE. GUIDANCE VALUES FOR RAINFALL IT WOULD
TAKE TO PRODUCE FLOODING ARE BELOW TWO INCHES FOR THE MOUNTAINS
AND ONLY AROUND AN INCH ACROSS THE VIRGINIA HIGHLANDS SO THE FLOOD
WATCH HAS BEEN EXTENDED TO COVER THOSE AREAS AS WELL. LIGHT TO
MODERATE RAIN WILL CONTINUE INTO THURSDAY ALONG THE BLUE RIDGE AND
IN THE FOOTHILLS IN FAR SOUTHWEST VIRGINIA INTO NORTHWEST NORTH
CAROLINA.
AT THIS TIME...THERE IS A LOW PROBABILITY OF MINOR MAINSTEM RIVER
FLOODING THROUGH THURSDAY. AREAL FLOODING OF SMALL STREAMS AND
CREEKS IS WHAT IS MORE LIKELY IF THE EXPECTED AMOUNT OF RAINFALL
OCCURS.
&&
.RNK WATCHES/WARNINGS/ADVISORIES...
VA...FLOOD WATCH UNTIL 8 PM EDT THIS EVENING FOR VAZ007-010-011-
018>020.
FLOOD WATCH UNTIL MIDNIGHT EDT TONIGHT FOR VAZ009-012-013-015-
016.
NC...FLOOD WATCH UNTIL MIDNIGHT EDT TONIGHT FOR NCZ001>003-018>020.
WV...FLOOD WATCH UNTIL 8 PM EDT THIS EVENING FOR WVZ042>044-507-508.
&&
$$
SYNOPSIS...DS/JH
NEAR TERM...JH
SHORT TERM...KK
LONG TERM...AMS
AVIATION...AMS/JH
HYDROLOGY...AMS/JH
AREA FORECAST DISCUSSION
NWS BLACKSBURG VA
703 AM EDT TUE APR 14 2015
.SYNOPSIS...
A COLD FRONT WILL SLIDE SOUTHEAST INTO THE AREA TODAY BEFORE
DROPPING SOUTH INTO THE CAROLINAS TONIGHT. A WEDGE OF HIGH
PRESSURE WILL BUILD IN BEHIND THE FRONT BY WEDNESDAY...AND LINGER
OVER THE REGION INTO AT LEAST FRIDAY. ANOTHER COLD FRONT WILL MOVE
ACROSS THE AREA OVER THE WEEKEND.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 230 AM EDT TUESDAY...
FORECAST REMAINS QUITE COMPLICATED GIVEN THE SLOW MOVING COLD FRONT TO
THE WEST AND ASSOCIATED WEAK LOW PRESSURE THAT WILL SCOOT OUT OF THE TN
VALLEY AND INTO THE REGION LATER TODAY. THIS JUST AS THE FRONT FOLDS IN
FROM THE NORTH/NW ALLOWING LOW LEVEL CONVERGENCE TO MAXIMIZE THIS
MORNING INTO LATE AFTERNOON. MODELS HAVE AGAIN TRENDED FARTHER NORTH
WITH THE MAIN BAROCLINIC ZONE WHICH HAS SHIFTED THE AXIS OF BEST UPPER
DIFFLUENCE AND CORRESPONDING LIFT FARTHER NORTH/WEST. THIS WHILE
ALLOWING LESS UPSLOPE GIVEN VEERING FLOW FROM SOUTH/SE TO MORE SW AHEAD
OF THE BOUNDARY TODAY. CONSENSUS APPEARS FOR A STRIP OF HIGHER QPF FROM
SE WEST VA EAST INTO THE VA HIGHLANDS AND POINTS EAST WITH A SHARP
GRADIENT LIKELY NEAR HIGHWAY 460 AND POINTS SOUTH WHERE WILL SEE
MORE SCATTERED COVERAGE IN COMPARISON TO THE WIDESPREAD/HEAVIER
SHRA UP NORTH. HOWEVER WHERE TO DRAW THE LINE QUITE IFFY GIVEN
LIKELY TREND OF THINGS BEING OVERALL SLOWER PER THE WAVE TRACKING
NEAR BRISTOL THIS AFTERNOON BEFORE SHUNTING EAST/SE. THIS MAY
ALLOW MUCH MORE OF A DIFFERENTIAL HEATING ZONE OVER THE SOUTH
WHERE THE LATEST NAM HAS CAPES NEAR 1K J/KG ALONG THE VA/NC BORDER
PENDING MORE BREAKS AND SUBSEQUENT HEATING. SPEED MAX TRACKING
ACROSS LATE MAY ALSO SPARK CLUSTERS OF TSRA THAT COULD LINE UP
BEFORE SPILLING SOUTH. THUS BEEFING UP THUNDER MENTION SOUTH AND
INCLUDING IN THE HWO PER DAY1 MARGINAL OUTLOOK.
OTRW HAVE ADJUSTED POPS DOWN SOME TO INIT EARLY ON...WITH HIGHER CAT
POPS NORTH/WEST FOR MUCH OF THE DAY...AND SLOWLY INCREASING FROM NORTH
TO SOUTH AS THE FRONT SAGS SOUTH AND THE WAVE HEADS EAST SIMILAR TO THE
NAM. FORECAST QPF OF 1-3 INCHES ESPCLY NW PROMPTS THE NEED TO EXTEND
THE FLOOD WATCH INTO THE VA HIGHLANDS GIVEN LOW FFG AND PERHAPS FARTHER
EAST LATER PENDING TRENDS. LONGER PERIOD OF WARM ADVECTION BEFORE THE
FLOW TURNS NE...AND POSSIBLY SOME SUN SOUTH SUGGESTS HIGHS WARMER
THAN PREVIOUS WITH MOST IN THE 60S TO LOWER 70S...AND SOME MID OR
EVEN UPPER 70S POSSIBLE FAR SOUTH IF THINGS BREAK OPEN MORE.
WAVE HEADS EAST THIS EVENING ALLOWING THE SURFACE FRONT TO BOW THROUGH
THE REGION FROM THE NORTH BRINGING THE ONSET OF THE LOW LEVEL WEDGE
FROM NE TO SW OVERNIGHT. THIS SHOULD TAKE THE DEFORMATION TYPE ZONE OF
HEAVIER SHRA TO THE EAST BY MIDNIGHT WITH RESIDUAL LEFTOVER MOISTURE
MAKING FOR CONTINUED SPOTTY -RA ESPCLY SW WHERE WILL SEE A WEAK
INVERTED TROUGH DEVELOP UNDER THE EASTERLY FLOW. THUS AFTER MOSTLY
LIKELY POPS DURING THE EARLY EVENING WILL SHIFT TO A MORE CHANCE REGIME
FOR -RA AND EVEN SOME SPOTTY -DZ AS THE NIGHT WEARS ON GIVEN THE
DECREASING DEPTH TO THE MOISTURE OFF FORECAST RAOBS LATE. KEPT TEMPS
SIMILAR TO THE SLIGHTLY WARMER MET MOS PER EXPECTED SLOWER TRENDS WITH
THE DEVELOPING CAD.
&&
.SHORT TERM /WEDNESDAY THROUGH THURSDAY NIGHT/...
AS OF 315 AM EDT TUESDAY...
EXPECTING THAT CONVECTION WILL DRIVE SFC COLD FRONT SOUTH OF US
BY WEDNESDAY MORNING ACROSS THE CAROLINAS. MAIN SHORTWAVE AND
ASSOCIATED LOW PRESSURE ALONG THE FRONT WILL BE OFFSHORE IN THE
ATLANTIC OCEAN. IN SITU CAD EVENT WILL BECOME WELL ESTABLISHED ON
WEDNESDAY. WITH CLOUDS AND RAIN...LOWERED HIGH TEMPERATURES FOR
WEDNESDAY. HIGHS FOR WEDNESDAY WILL BE BELOW NORMAL WITH READINGS
FROM AROUND 50 DEGREES IN THE MOUNTAINS TO NEAR 60 DEGREES IN THE
PIEDMONT. IN GENERAL...LEANED POPS TOWARDS THE NAM FOR WEDNESDAY AND
SHAPED OUR QPF TOWARDS HPC.
CLOUDY WITH AREAS OF RAIN AND FOG ARE ANTICIPATED WEDNESDAY NIGHT
INTO THURSDAY. PLACED HIGH POPS ACROSS THE SOUTH WHERE WEDGE UPGLIDE
OVERLAPS WITH SOME UPPER DIVERGENCE. LOW TEMPERATURES WEDNESDAY
NIGHT WILL RANGE FROM THE UPPER 30S IN THE MOUNTAINS TO THE LOWER
40S IN THE PIEDMONT. UNDERCUT MOS HIGH TEMPERATURES FOR THURSDAY
WITH PLENTY OF CLOUDS AND AREAS OF RAIN AND FOG UNDER CAD. HIGHS
WILL VARY FROM THE UPPER 40S IN THE NORTHWEST TO THE MID 50S IN THE
SOUTHEAST. THE CLOUDY DREARY WEATHER CONTINUES THURSDAY NIGHT INTO
FRIDAY WITH LOW TEMPERATURES GENERALLY FROM THE LOWER 40S IN THE
NORTHWEST MOUNTAINS TO THE LOWER 50S IN THE PIEDMONT.
&&
.LONG TERM /FRIDAY THROUGH MONDAY/...
AS OF 215 PM EDT MONDAY...
NORTHERN STREAM TROF OVER THE NORTHEAST AMPLIFIES WITH A SURFACE
COLD FRONT COMING THROUGH THE REGION ON SATURDAY. MEANWHILE A LOW IS
CLOSED OFF OVER THE ROCKIES ON FRIDAY.
CLOSED LOW OVER THE ROCKIES OPENS UP AND ALSO TRACKS INTO THE UPPER
MISSISSIPPI VALLEY SATURDAY AND SUNDAY...WITH A PIECE OF THIS SYSTEM
REACHING THE FORECAST AREA ON MONDAY. SURFACE HIGH PRESSURE CROSSES
THE NORTHEAST UNITED STATES SUNDAY THEN BY MONDAY...ALREADY BACK IN
YET ANOTHER WEDGE WITH DEEP SOUTHEAST UPSLOPE FLOW WITH STRONG 850
WINDS.
WILL KEEP SATURDAY NIGHT THROUGH SUNDAY NIGHT DRY. WEDGE MAY BE SLOW
TO BREAK ON FRIDAY WHICH MAY LIMIT MAXIMUM TEMPERATURES. BUT
SATURDAY AHEAD OF THE FRONT WILL BE MILDER. TEMPERATURES BEHIND THE
FRONT ON SUNDAY WILL BE AROUND NORMAL.
&&
.AVIATION /12Z TUESDAY THROUGH SATURDAY/...
AS OF 640 AM EDT TUESDAY...
CIGS LOWERING THROUGH MVFR EARLY THIS MORNING AS MOISTURE
INCREASES AHEAD OF THE FRONT TO THE WEST AND WEAK LOW PRESSURE
TRAVERSING THROUGH THE TN VALLEY. HOWEVER ONGOING RAINFALL REMAINS
LIMITED GIVEN BEST LIFT TO THE WEST WITH ONLY A SLOW INFLUX OF
STRATUS ONGOING MAINLY VIA SOUTH/SE UPSLOPE FLOW ACROSS THE WEST.
MODELS REMAIN TOO FAST IN LOWERING CIGS/VSBYS SO GIVEN CURRENT
TRENDS WILL BACK OFF ONSET OF IFR/LIFR CONDITIONS FOR A WHILE WITH
POTENTIAL FOR MOST LOCATIONS TO STAY AT LEAST MVFR THROUGH MIDDAY.
OTRW WILL KEEP THE GOING EARLIER TREND IN HOLDING MOST SPOTS MVFR
INTO EARLY AFTERNOON WITH OCNL MVFR VSBYS AT TIMES ESPCLY
KLWB/KBLF THIS MORNING...AND ELSEWHERE THIS AFTERNOON AS THE
FRONT DIPS SOUTH AND RAINFALL BECOMES MORE WIDESPREAD.
ONCE THE FRONT BACKDOORS SOUTH INTO THE AREA THIS AFTERNOON WILL
SEE WINDS BECOME MORE EASTERLY FROM NORTH TO SOUTH DURING THE DAY
BUT MUCH SLOWER THAN EARLIER GIVEN THE FORECAST TRACK OF THE WAVE
TO BE FARTHER NORTH. THIS MAY AGAIN LIMIT THE SHOWER COVERAGE AT
KBCB/KROA/KDAN UNTIL LATER IN THE DAY WITH A SHARP GRADIENT
BETWEEN IFR/MVFR CIGS FROM KLWB/KLYH AND POINTS SOUTH WITH PERHAPS
MVFR TO VFR FOR A WHILE AROUND KDAN BEFORE LOWERING THIS AFTERNOON
AS THE FRONT/WAVE COMBO ACROSS THE REGION. FOR NOW WILL DELAY
LOWER CIGS FURTHER SOUTH THIS AFTERNOON BUT BRING ALL A PERIOD OF
IFR DURING THE AFTERNOON WITH A LONGER DURATION OF CONVECTIVE
POTENTIAL ACROSS THE SOUTH AT KDAN.
WAVE SHUNTS TO THE SE TONIGHT ALLOWING A DEEPENING WEDGE TO TAKE
SHAPE WITH WIDESPREAD IFR TO MVFR IN LINGERING LIGHT RAIN/DRIZZLE
AND FOG INTO THE OVERNIGHT.
EXTENDED AVIATION...
WEDNESDAY INTO THURSDAY...HIGH PRESSURE BEHIND THE FRONT WILL NOSE
SOUTH ALONG THE LEE OF THE APPALACHIANS...SETTING THE SCENE FOR A
COLD AIR DAMMING SCENARIO. AFTER A POTENTIAL BRIEF DECREASE IN
PRECIPITATION LATE TUESDAY NIGHT INTO EARLY WEDNESDAY...SOUTHEAST
FLOW WILL ALLOW FOR PRECIPITATION AND MORE IFR/MVFR CONDITIONS
ACROSS THE AREA...ESPECIALLY ACROSS THE SOUTHWEST PARTS OF THE
AREA.
THURSDAY NIGHT INTO FRIDAY...MODEL GUIDANCE DIFFERS ON THE
TIMING...BUT THE GENERAL TREND WILL BE ON THAT ALLOWS THE WEDGE TO
SLOWLY GIVES WAY TO INCREASING SOUTHWEST FLOW AHEAD OF A
SHORTWAVE TROUGH PROGRESSING INTO THE GREAT LAKES REGION...BUT NOT
COMPLETELY. THIS SHOULD ALLOW FOR SOME IMPROVEMENT TO FLIGHT
CATEGORIES...BUT SCATTERED SHOWERS AND THUNDERSTORMS WILL STILL BE
AN ISSUE.
THE AFOREMENTIONED SHORTWAVE TROUGH FRONT WILL BRING A COLD FRONT
THROUGH THE AREA ON SATURDAY. LOOK FOR MORE SUB-VFR
CONDITIONS...SHOWERS AND STORMS TO IMPACT THE AREA.
&&
.HYDROLOGY...
AS OF 330 AM EDT TUESDAY...
SHOWERS REMAIN SCATTERED ACROSS THE REGION EARLY THIS MORNING WITH
THE FRONT STILL WELL TO THE NW AND LOW PRESSURE OVER THE TN
VALLEY. LATEST HRRR SHOWS A SLOW FILLING IN OF PRECIP THROUGH THE
MORNING WITH THE MOST WIDESPREAD COVERAGE ESPCLY NORTHERN HALF
FROM MIDDAY THROUGH LATE AFTERNOON.
EXPECTED RAINFALL FOR MUCH OF THE FORECAST AREA WILL BE ONE TO TWO
INCHES EARLY WEDNESDAY. HOWEVER MODELS HAVE SHIFTED THE HEAVIER
AXIS OF PROJECTED RAINFALL NORTH ACROSS PARTS OF SOUTHEAST WEST
VIRGINIA INTO THE VIRGINIA HIGHLANDS WHERE POTENTIAL FOR TWO TO
THREE INCHES LOOKS POSSIBLE. GUIDANCE VALUES FOR RAINFALL IT WOULD
TAKE TO PRODUCE FLOODING ARE BELOW TWO INCHES FOR THE MOUNTAINS
AND ONLY AROUND AN INCH ACROSS THE VIRGINIA HIGHLANDS SO THE FLOOD
WATCH HAS BEEN EXTENDED TO COVER THOSE AREAS AS WELL. LIGHT TO
MODERATE RAIN WILL CONTINUE INTO THURSDAY ALONG THE BLUE RIDGE AND
IN THE FOOTHILLS IN FAR SOUTHWEST VIRGINIA INTO NORTHWEST NORTH
CAROLINA.
AT THIS TIME...THERE IS A LOW PROBABILITY OF MINOR MAINSTEM RIVER
FLOODING THROUGH THURSDAY. AREAL FLOODING OF SMALL STREAMS AND
CREEKS IS WHAT IS MORE LIKELY IF THE EXPECTED AMOUNT OF RAINFALL
OCCURS.
&&
.RNK WATCHES/WARNINGS/ADVISORIES...
VA...FLOOD WATCH THROUGH THIS EVENING FOR VAZ007-010-011-018>020.
FLOOD WATCH THROUGH THIS EVENING FOR VAZ009-012-013-015-016.
NC...FLOOD WATCH THROUGH THIS EVENING FOR NCZ001>003-018>020.
WV...FLOOD WATCH THROUGH THIS EVENING FOR WVZ042>044-507-508.
&&
$$
SYNOPSIS...DS/JH
NEAR TERM...JH
SHORT TERM...KK
LONG TERM...AMS
AVIATION...DS/JH/MBS
HYDROLOGY...AMS/JH
AREA FORECAST DISCUSSION
NWS BLACKSBURG VA
342 AM EDT TUE APR 14 2015
.SYNOPSIS...
A COLD FRONT WILL SLIDE SOUTHEAST INTO THE AREA TODAY BEFORE
DROPPING SOUTH INTO THE CAROLINAS TONIGHT. A WEDGE OF HIGH
PRESSURE WILL BUILD IN BEHIND THE FRONT BY WEDNESDAY...AND LINGER
OVER THE REGION INTO AT LEAST FRIDAY. ANOTHER COLD FRONT WILL MOVE
ACROSS THE AREA OVER THE WEEKEND.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 230 AM EDT TUESDAY...
FORECAST REMAINS QUITE COMPLICATED GIVEN THE SLOW MOVING COLD FRONT TO
THE WEST AND ASSOCIATED WEAK LOW PRESSURE THAT WILL SCOOT OUT OF THE TN
VALLEY AND INTO THE REGION LATER TODAY. THIS JUST AS THE FRONT FOLDS IN
FROM THE NORTH/NW ALLOWING LOW LEVEL CONVERGENCE TO MAXIMIZE THIS
MORNING INTO LATE AFTERNOON. MODELS HAVE AGAIN TRENDED FARTHER NORTH
WITH THE MAIN BAROCLINIC ZONE WHICH HAS SHIFTED THE AXIS OF BEST UPPER
DIFFLUENCE AND CORRESPONDING LIFT FARTHER NORTH/WEST. THIS WHILE
ALLOWING LESS UPSLOPE GIVEN VEERING FLOW FROM SOUTH/SE TO MORE SW AHEAD
OF THE BOUNDARY TODAY. CONSENSUS APPEARS FOR A STRIP OF HIGHER QPF FROM
SE WEST VA EAST INTO THE VA HIGHLANDS AND POINTS EAST WITH A SHARP
GRADIENT LIKELY NEAR HIGHWAY 460 AND POINTS SOUTH WHERE WILL SEE
MORE SCATTERED COVERAGE IN COMPARISON TO THE WIDESPREAD/HEAVIER
SHRA UP NORTH. HOWEVER WHERE TO DRAW THE LINE QUITE IFFY GIVEN
LIKELY TREND OF THINGS BEING OVERALL SLOWER PER THE WAVE TRACKING
NEAR TRI THIS AFTERNOON BEFORE SHUNTING EAST/SE. THIS MAY ALLOW
MUCH MORE OF A DIFFERENTIAL HEATING ZONE OVER THE SOUTH WHERE THE
LATEST NAM HAS CAPES NEAR 1K J/KG ALONG THE VA/NC BORDER PENDING
MORE BREAKS AND SUBSEQUENT HEATING. SPEED MAX TRACKING ACROSS LATE
MAY ALSO SPARK CLUSTERS OF TSRA THAT COULD LINE UP BEFORE SPILLING
SOUTH. THUS BEEFING UP THUNDER MENTION SOUTH AND INCLUDING IN THE
HWO PER DAY1 MARGINAL OUTLOOK.
OTRW HAVE ADJUSTED POPS DOWN SOME TO INIT EARLY ON...WITH HIGHER CAT
POPS NORTH/WEST FOR MUCH OF THE DAY...AND SLOWLY INCREASING FROM NORTH
TO SOUTH AS THE FRONT SAGS SOUTH AND THE WAVE HEADS EAST SIMILAR TO THE
NAM. FORECAST QPF OF 1-3 INCHES ESPCLY NW PROMPTS THE NEED TO EXTEND
THE FLOOD WATCH INTO THE VA HIGHLANDS GIVEN LOW FFG AND PERHAPS FARTHER
EAST LATER PENDING TRENDS. LONGER PERIOD OF WARM ADVECTION BEFORE THE
FLOW TURNS NE...AND POSSIBLY SOME SUN SOUTH SUGGESTS HIGHS WARMER
THAN PREVIOUS WITH MOST IN THE 60S TO LOWER 70S...AND SOME MID OR
EVEN UPPER 70S POSSIBLE FAR SOUTH IF THINGS BREAK OPEN MORE.
WAVE HEADS EAST THIS EVENING ALLOWING THE SURFACE FRONT TO BOW THROUGH
THE REGION FROM THE NORTH BRINGING THE ONSET OF THE LOW LEVEL WEDGE
FROM NE TO SW OVERNIGHT. THIS SHOULD TAKE THE DEFORMATION TYPE ZONE OF
HEAVIER SHRA TO THE EAST BY MIDNIGHT WITH RESIDUAL LEFTOVER MOISTURE
MAKING FOR CONTINUED SPOTTY -RA ESPCLY SW WHERE WILL SEE A WEAK
INVERTED TROUGH DEVELOP UNDER THE EASTERLY FLOW. THUS AFTER MOSTLY
LIKELY POPS DURING THE EARLY EVENING WILL SHIFT TO A MORE CHANCE REGIME
FOR -RA AND EVEN SOME SPOTTY -DZ AS THE NIGHT WEARS ON GIVEN THE
DECREASING DEPTH TO THE MOISTURE OFF FORECAST RAOBS LATE. KEPT TEMPS
SIMILAR TO THE SLIGHTLY WARMER MET MOS PER EXPECTED SLOWER TRENDS WITH
THE DEVELOPING CAD.
&&
.SHORT TERM /WEDNESDAY THROUGH THURSDAY NIGHT/...
AS OF 315 AM EDT TUESDAY...
EXPECTING THAT CONVECTION WILL DRIVE SFC COLD FRONT SOUTH OF US
BY WEDNESDAY MORNING ACROSS THE CAROLINAS. MAIN SHORTWAVE AND
ASSOCIATED LOW PRESSURE ALONG THE FRONT WILL BE OFFSHORE IN THE
ATLANTIC OCEAN. IN SITU CAD EVENT WILL BECOME WELL ESTABLISHED ON
WEDNESDAY. WITH CLOUDS AND RAIN...LOWERED HIGH TEMPERATURES FOR
WEDNESDAY. HIGHS FOR WEDNESDAY WILL BE BELOW NORMAL WITH READINGS
FROM AROUND 50 DEGREES IN THE MOUNTAINS TO NEAR 60 DEGREES IN THE
PIEDMONT. IN GENERAL...LEANED POPS TOWARDS THE NAM FOR WEDNESDAY AND
SHAPED OUR QPF TOWARDS HPC.
CLOUDY WITH AREAS OF RAIN AND FOG ARE ANTICIPATED WEDNESDAY NIGHT
INTO THURSDAY. PLACED HIGH POPS ACROSS THE SOUTH WHERE WEDGE UPGLIDE
OVERLAPS WITH SOME UPPER DIVERGENCE. LOW TEMPERATURES WEDNESDAY
NIGHT WILL RANGE FROM THE UPPER 30S IN THE MOUNTAINS TO THE LOWER
40S IN THE PIEDMONT. UNDERCUT MOS HIGH TEMPERATURES FOR THURSDAY
WITH PLENTY OF CLOUDS AND AREAS OF RAIN AND FOG UNDER CAD. HIGHS
WILL VARY FROM THE UPPER 40S IN THE NORTHWEST TO THE MID 50S IN THE
SOUTHEAST. THE CLOUDY DREARY WEATHER CONTINUES THURSDAY NIGHT INTO
FRIDAY WITH LOW TEMPERATURES GENERALLY FROM THE LOWER 40S IN THE
NORTHWEST MOUNTAINS TO THE LOWER 50S IN THE PIEDMONT.
&&
.LONG TERM /FRIDAY THROUGH MONDAY/...
AS OF 215 PM EDT MONDAY...
NORTHERN STREAM TROF OVER THE NORTHEAST AMPLIFIES WITH A SURFACE
COLD FRONT COMING THROUGH THE REGION ON SATURDAY. MEANWHILE A LOW IS
CLOSED OFF OVER THE ROCKIES ON FRIDAY.
CLOSED LOW OVER THE ROCKIES OPENS UP AND ALSO TRACKS INTO THE UPPER
MISSISSIPPI VALLEY SATURDAY AND SUNDAY...WITH A PIECE OF THIS SYSTEM
REACHING THE FORECAST AREA ON MONDAY. SURFACE HIGH PRESSURE CROSSES
THE NORTHEAST UNITED STATES SUNDAY THEN BY MONDAY...ALREADY BACK IN
YET ANOTHER WEDGE WITH DEEP SOUTHEAST UPSLOPE FLOW WITH STRONG 850
WINDS.
WILL KEEP SATURDAY NIGHT THROUGH SUNDAY NIGHT DRY. WEDGE MAY BE SLOW
TO BREAK ON FRIDAY WHICH MAY LIMIT MAXIMUM TEMPERATURES. BUT
SATURDAY AHEAD OF THE FRONT WILL BE MILDER. TEMPERATURES BEHIND THE
FRONT ON SUNDAY WILL BE AROUND NORMAL.
&&
.AVIATION /08Z TUESDAY THROUGH SATURDAY/...
AS OF 1250 AM EDT TUESDAY...
CIGS GRADUALLY LOWERING TO MVFR FROM SW TO NE TONIGHT AS MOISTURE
INCREASES AHEAD OF THE FRONT TO THE WEST AND WEAK LOW PRESSURE
TRAVERSING THROUGH THE TN VALLEY. HOWEVER ONGOING RAINFALL REMAINS
LIMITED GIVEN BEST LIFT TO THE WEST WITH ONLY A SLOW INFLUX OF
STRATUS ONGOING MAINLY VIA SOUTH/SE UPSLOPE FLOW ACROSS THE WEST.
MODELS REMAIN TOO FAST IN LOWERING CIGS/VSBYS SO GIVEN CURRENT
TRENDS WILL BACK OFF ONSET OF IFR/LIFR CONDITIONS FOR A WHILE WITH
POTENTIAL FOR KLYH TO STAY VFR TO MVFR INTO TUESDAY MORNING.
ELSEWHERE WILL LOWER TO MVFR BEFORE DAYBREAK AND THEN DROP
NORTHERN/WESTERN LOCATIONS INTO IFR AS THE FRONT DIPS SOUTH BUT
LOW CONFIDENCE IN SEEING IFR CIGS PERSIST AT KDAN WHERE EXPECT MAY
MIX OUT THIS MORNING AND THEN LOWER IN DEVELOPING SHRA LATER ON.
ONCE THE FRONT BACKDOORS SOUTH INTO THE AREA TUESDAY WILL SEE
WINDS BECOME MORE EASTERLY FROM NORTH TO SOUTH DURING THE DAY BUT
MUCH SLOWER THAN EARLIER GIVEN THE FORECAST TRACK OF THE WAVE TO
BE FARTHER NORTH. THIS MAY AGAIN LIMIT THE SHOWER COVERAGE AT
KBCB/KROA/KDAN UNTIL LATER IN THE DAY WITH A SHARP GRADIENT
BETWEEN IFR/MVFR CIGS FROM KLWB TO KLYH AND PERHAPS MVFR TO VFR
FOR A WHILE BEFORE LOWERING TUESDAY AFTERNOON AS THE FRONT/WAVE
COMBO ACROSS THE REGION. FOR NOW WILL DELAY LOWER CIGS FURTHER
DURING TUESDAY BUT BRING ALL A PERIOD OF IFR DURING THE DAY WITH A
LONGER DURATION OF CONVECTIVE POTENTIAL ACROSS THE SOUTH AT KDAN.
WAVE SHUNTS TO THE SE TUESDAY NIGHT ALLOWING A DEEPENING WEDGE TO
TAKE SHAPE WITH WIDESPREAD IFR TO MVFR IN LINGERING LIGHT
RAIN/DRIZZLE FOG INTO THE OVERNIGHT.
EXTENDED AVIATION...
WEDNESDAY INTO THURSDAY...HIGH PRESSURE BEHIND THE FRONT WILL NOSE
SOUTH ALONG THE LEE OF THE APPALACHIANS...SETTING THE SCENE FOR A
COLD AIR DAMMING SCENARIO. AFTER A POTENTIAL BRIEF DECREASE IN
PRECIPITATION LATE TUESDAY NIGHT INTO EARLY WEDNESDAY...SOUTHEAST
FLOW WILL ALLOW FOR PRECIPITATION AND MORE IFR/MVFR CONDITIONS
ACROSS THE AREA...ESPECIALLY ACROSS THE SOUTHWEST PARTS OF THE
AREA.
THURSDAY NIGHT INTO FRIDAY...MODEL GUIDANCE DIFFERS ON THE
TIMING...BUT THE GENERAL TREND WILL BE ON THAT ALLOWS THE WEDGE TO
SLOWLY GIVES WAY TO INCREASING SOUTHWEST FLOW AHEAD OF A
SHORTWAVE TROUGH PROGRESSING INTO THE GREAT LAKES REGION...BUT NOT
COMPLETELY. THIS SHOULD ALLOW FOR SOME IMPROVEMENT TO FLIGHT
CATEGORIES...BUT SCATTERED SHOWERS AND THUNDERSTORMS WILL STILL BE
AN ISSUE.
THE AFOREMENTIONED SHORTWAVE TROUGH FRONT WILL BRING A COLD FRONT
THROUGH THE AREA ON SATURDAY. LOOK FOR MORE SUB-VFR
CONDITIONS...SHOWERS AND STORMS TO IMPACT THE AREA.
&&
.HYDROLOGY...
AS OF 330 AM EDT TUESDAY...
SHOWERS REMAIN SCATTERED ACROSS THE REGION EARLY THIS MORNING WITH
THE FRONT STILL WELL TO THE NW AND LOW PRESSURE OVER THE TN
VALLEY. LATEST HRRR SHOWS A SLOW FILLING IN OF PRECIP THROUGH THE
MORNING WITH THE MOST WIDESPREAD COVERAGE ESPCLY NORTHERN HALF
FROM MIDDAY THROUGH LATE AFTERNOON.
EXPECTED RAINFALL FOR MUCH OF THE FORECAST AREA WILL BE ONE TO TWO
INCHES EARLY WEDNESDAY. HOWEVER MODELS HAVE SHIFTED THE HEAVIER
AXIS OF PROJECTED RAINFALL NORTH ACROSS PARTS OF SOUTHEAST WEST
VIRGINIA INTO THE VIRGINIA HIGHLANDS WHERE POTENTIAL FOR TWO TO
THREE INCHES LOOKS POSSIBLE. GUIDANCE VALUES FOR RAINFALL IT WOULD
TAKE TO PRODUCE FLOODING ARE BELOW TWO INCHES FOR THE MOUNTAINS
AND ONLY AROUND AN INCH ACROSS THE VIRGINIA HIGHLANDS SO THE FLOOD
WATCH HAS BEEN EXTENDED TO COVER THOSE AREAS AS WELL. LIGHT TO
MODERATE RAIN WILL CONTINUE INTO THURSDAY ALONG THE BLUE RIDGE AND
IN THE FOOTHILLS IN FAR SOUTHWEST VIRGINIA INTO NORTHWEST NORTH
CAROLINA.
AT THIS TIME...THERE IS A LOW PROBABILITY OF MINOR MAINSTEM RIVER
FLOODING THROUGH THURSDAY. AREAL FLOODING OF SMALL STREAMS AND
CREEKS IS WHAT IS MORE LIKELY IF THE EXPECTED AMOUNT OF RAINFALL
OCCURS.
&&
.RNK WATCHES/WARNINGS/ADVISORIES...
VA...FLOOD WATCH THROUGH THIS EVENING FOR VAZ007-010-011-018>020.
FLOOD WATCH THROUGH THIS EVENING FOR VAZ009-012-013-015-016.
NC...FLOOD WATCH THROUGH THIS EVENING FOR NCZ001>003-018>020.
WV...FLOOD WATCH THROUGH THIS EVENING FOR WVZ042>044-507-508.
&&
$$
SYNOPSIS...DS/JH
NEAR TERM...JH
SHORT TERM...KK
LONG TERM...AMS
AVIATION...DS/JH/MBS
HYDROLOGY...JH/AMS
YOU CAN SEE AN ILLUSTRATED VERSION OF THE FORECAST DISCUSSION AT
WWW.WEATHER.GOV/SEATTLE/GAFD/LATEST_WEBAFD.HTML
AREA FORECAST DISCUSSION
NWS GREEN BAY WI
1231 PM CDT TUE APR 14 2015
UPDATED AVIATION PORTION FOR 18Z TAF ISSUANCE
.SHORT TERM...TODAY...TONIGHT...AND WEDNESDAY
ISSUED AT 308 AM CDT TUE APR 14 2015
THE LATEST RAP ANALYSIS AND SATELLITE/RADAR IMAGERY SHOW SPLIT FLOW
ACROSS NORTH AMERICA CONSISTING OF A RIDGE OVER THE ROCKIES...A
TROUGH OVER THE SOUTHERN PLAINS...AND CONVERGING UPPER FLOW ACROSS
THE EAST. THE WESTERN GREAT LAKES RESIDES DOWNSTREAM OF THE
RIDGE...WITH STRONG SUBSIDENCE LEADING TO CLEAR CONDITIONS ACROSS
THE REGION. THE AIRMASS ITSELF IS VERY DRY WITH PWATS FALLING BELOW
A QUARTER OF AN INCH. AS THE DRY SURFACE HIGH MOVES ACROSS THE
REGION...TEMPS AND HUMIDITIES ARE THE MAIN FORECAST CONCERNS THROUGH
WEDNESDAY.
TODAY...HIGH PRESSURE WILL DRIFT ACROSS THE REGION...WHICH WILL
PROMOTE CLEAR SKIES AND LIGHT WINDS. EVEN THOUGH UPSTREAM OBS SAW
DEWPOINTS CRASH INTO THE SINGLE DIGITS OVER MINNESOTA AND NORTH
DAKOTA IN THIS AIRMASS...SHOULD NOT HAVE THE KIND OF MECHANICAL
MIXING THIS REGION SAW YESTERDAY. HOWEVER...SHOULD SEE MIXING UP TO
800-750MB...WHICH SUPPORTS DROPPING DEWPOINTS INTO THE LOW TEENS UP
NORTH. COMBINED WITH HIGHS MAINLY IN THE MID TO UPPER 60S AWAY FROM
LAKE MICHIGAN...HUMIDITIES SHOULD FALL INTO THE TEENS. ELEVATED
FIRE WEATHER CONDITIONS WILL THEREFORE CONTINUE TODAY.
TONIGHT...HIGH PRESSURE WILL REMAIN PRESENT ACROSS THE REGION.
SHOULD SEE THIN CIRRUS INVADE FROM THE SOUTH AHEAD OF A WEAK UPPER
LOW ACROSS THE PLAINS. OTHERWISE QUIET...WITH LOWS FALLING INTO THE
UPPER 30S TO LOW 40S.
WEDNESDAY...CIRRUS WILL CONTINUE TO INVADE THE REGION AND BECOME
THICKER...WHICH WILL LEAD TO FILTERED SUNSHINE. THE SURFACE HIGH
WILL MOVE TO THE EASTERN GREAT LAKES...WHICH WILL CAUSE EAST TO
SOUTHEAST WINDS TO BECOME RELATIVELY STRONGER THAN TODAYS EXPECTED
SPEEDS. THE AIRMASS WILL MOISTURE SOME...BUT STILL WENT WITH THE
LOWEST GUIDANCE...WHICH PLACES RH VALUES BETWEEN 15 TO 25 PERCENT.
NO REPRIEVE FROM ELEVATED FIRE WEATHER CONDITIONS AS A RESULT.
.LONG TERM...WEDNESDAY NIGHT THROUGH MONDAY
ISSUED AT 308 AM CDT TUE APR 14 2015
CONTINUED WARM AND DRY CONDITIONS WILL CONTINUE INTO THE
WEEKEND...WITH ONLY A SMALL CHANCE OF SHOWERS FRIDAY INTO FRIDAY
EVENING. A MORE POTENT SYSTEM IS EXPECTED TO AFFECT THE REGION
EARLY NEXT WEEK.
FOR WEDNESDAY NIGHT...AN UPPER LEVEL DISTURBANCE WILL MOVE ACROSS THE
REGION. MODEL SOUNDINGS WERE BONE DRY...THUS REMOVED ANY MENTION OF
RAIN DESPITE STEEP MID LEVEL LAPSE RATES WITH THIS SYSTEM. ON
THURSDAY...MODEL SOUNDINGS STILL SHOW VERY DRY SOUNDINGS ALTHOUGH
NOT AS DRY AS TUESDAY AND WEDNESDAY SOUNDINGS. DID LOWER DEW
POINTS BY 3 TO 5 DEGREES MOST PLACES AS A STARTING POINT. WEAK
BOUNDARY EXPECTED TO MOVE ACROSS THE REGION ON FRIDAY...BRINGING
A SMALL CHANCE OF SHOWERS. MODELS DO SHOW MORE MOISTURE WITH THIS
FEATURE TO SUPPORT THE SMALL CHANCE OF SHOWERS.
HIGH PRESSURE WILL BUILD INTO THE REGION ON SATURDAY AND CONTINUE
INTO SUNDAY. VERY DRY CONDITIONS ARE EXPECTED AGAIN SATURDAY WITH
VERY LOW AFTERNOON RELATIVE HUMIDITY READINGS. ATTENTION THEN TURNS
TO UPPER LOW ACROSS THE CENTRAL UNITED STATES WILL INTERACT WITH
500MB TROUGH MOVING ACROSS SOUTHERN CANADA. THIS FEATURE SHOULD
ALLOW FOR LOW PRESSURE TO FORM AND BRING A CHANCE OF RAIN TO THE
AREA SUNDAY NIGHT AND MONDAY.
DID LOWER MIN TEMPERATURES WEDNESDAY NIGHT AND THURSDAY NIGHT...
WHILE RAISING MAX TEMPERATURES A DEGREE OR TWO ON MOST DAYS INTO
THE WEEKEND.
&&
.AVIATION...FOR 18Z TAF ISSUANCE
ISSUED AT 1230 PM CDT TUE APR 14 2015
EXCELLENT FLYING CONDITIONS EXPECTED OVER THE NEXT 24 HOURS AS
HI PRES MOVES THRU THE GREAT LAKES. WEST WINDS AT 5 TO 10 KTS THIS
AFTERNOON WL GO LGT/VRBL TNGT AND THEN BACK TO THE SE AT AROUND 10
KTS ON WED. VFR CONDITIONS TO PREVAIL WITH ONLY HI CLOUDS
STREAMING OVERHEAD.
&&
.GRB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM.....MPC
LONG TERM......ECKBERG
AVIATION.......AK
AREA FORECAST DISCUSSION...UPDATED
NWS MILWAUKEE/SULLIVAN WI
940 AM CDT TUE APR 14 2015
.UPDATE...
AREA OF HIGH PRESSURE WILL STAY IN CONTROL OVER THE REGION TODAY.
CLEAR SKIES AND LIGHT WINDS WILL PERSIST THROUGHOUT THE DAY. DEW
POINTS LOOK TO DROP INTO THE LOWER 20S AND UPPER TEENS AS THE
BOUNDARY LAYER LOOKS TO MIX UP TO NEAR THE 800MB LEVEL ACCORDING
TO RAP MODEL BUFKIT SOUNDINGS. THE 14Z RACINE OBS SHOW AN 8KT
NORTHEAST WIND...INDICATING THE LAKE MI SEA BREEZE HAS ALREADY
ACTIVATED. TEMPS WILL BE COOLER ALONG THE LAKE SHORE THAN FURTHER
INLAND DUE TO THE SEA BREEZE.
&&
.AVIATION/18Z TAFS/...
VFR CONDITIONS WILL CONTINUE THROUGH THE TAF PERIOD. HIGH CIRRUS
CLOUDS WILL STICK AROUND FOR THE MORNING AND AFTN HOURS ALONG WITH
LIGHT WINDS. AN 8KT NORTHEAST WIND WAS REPORTED AT RACINE AT
14Z...SO THE LAKE BREEZE HAS ALREADY ACTIVATED. THESE ON-SHORE
WINDS COULD APPEAR IN ENW AND MKE WITHIN THE NEXT FEW HOURS.
&&
.PREV DISCUSSION... /ISSUED 329 AM CDT TUE APR 14 2015/
SHORT TERM...
TODAY AND TONIGHT...FORECAST CONFIDENCE IS HIGH.
DEEP RIDGING WILL BRING QUIET WEATHER ACROSS THE AREA. THE CENTER OF
THE SURFACE HIGH PRESSURE WILL SLIDE ACROSS SOUTHERN WISCONSIN
TODAY. SO LIGHT WINDS AND FULL SUNSHINE EXPECTED. EASTERLY WINDS
WILL KICK IN BY LAKE MICHIGAN...SO MUCH COOLER NEAR THE LAKE VS
INLAND AREAS. SOUNDINGS SHOW GOOD MIXING UP TO 850MB SO DEWPOINTS
SHOULD TANK INTO THE TEENS TO LOWER 20S MOST PLACES...EXCEPT NEAR
THE LAKE.
THE DRY DEWPOINTS SHOULD ALLOW FOR SOME DECENT RADIATIONAL COOLING
TONIGHT...THOUGH AS THE RIDGE SLIDES EAST OF US BY EVENING...THE
RETURN FLOW WILL TEMPER SOME OF THAT.
WEDNESDAY THROUGH THURSDAY NIGHT...FORECAST CONFIDENCE HIGH.
SURFACE HIGH PRESSURE WILL DOMINATE THIS PERIOD AND BRING QUIET AND
MILD WEATHER TO SOUTHERN WI. IT WILL BE WARM INLAND WITH HIGHS IN
THE UPPER 60S... BUT A STEADY EAST WIND OFF THE LAKE WILL KEEP
LAKESHORE TEMPS IN THE 50S.
A MID LEVEL SHORTWAVE WILL BRING SOME CLOUDS TO THE AREA WED NIGHT
INTO THU MORNING. THERE COULD BE A FEW SPRINKLES WITH THIS FEATURE
BUT OVERALL A DRY FORECAST.
LONG TERM...
FRIDAY THROUGH MONDAY... FORECAST CONFIDENCE MEDIUM.
IT IS VERY TYPICAL FOR VARIOUS MODELS TO HANDLE CLOSED UPPER LOWS IN
DIFFERENT WAYS. A CLOSED UPPER LOW OVER THE FOUR CORNERS REGION WILL
EJECT INTO THE PLAINS LATER IN THE WEEK AND EVENTUALLY GET ABSORBED
INTO AN UPPER TROUGH SWINGING THROUGH THE UPPER MIDWEST AND GREAT
LAKES EARLY NEXT WEEK.
A SHORTWAVE TROUGH TRACKING ACROSS SOUTHERN ONTARIO COULD BRING SOME
LIGHT RAIN TO PORTIONS OF SOUTHERN WI ALONG A SURFACE TROUGH FRI
AFTERNOON AND EVENING. ONLY A SLIGHT CHANCE IN THE FCST SINCE MOST
MODELS KEEP US DRY. THE GFS IS THE WET MODEL FOR THE WEEKEND...
SINCE IT EJECTS THAT CLOSED UPPER LOW INTO THE MIDWEST EARLIER
THAN THE ECWMF AND CANADIAN MODELS. THE ECWMF AND CANADIAN MODELS
ARE DELAYED UNTIL SUNDAY NIGHT/MONDAY. WENT WITH A CONSENSUS OF
MODELS FOR PRECIP CHANCES FOR THIS PERIOD.
TEMPERATURES WILL BE COOLER FOR THE FIRST HALF OF NEXT WEEK IN THE
WAKE OF THE UPPER TROUGH WITH HIGHS IN THE 50S.
AVIATION/12Z TAFS/...
VFR CONDITIONS THROUGH THE TAF PERIOD. WINDS LESS THAN 10KTS.
&&
.MKX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
LM...NONE.
&&
$$
UPDATE...JTS
TODAY/TONIGHT AND AVIATION/MARINE...DAVIS
WEDNESDAY THROUGH MONDAY...MRC
AREA FORECAST DISCUSSION
NWS GREEN BAY WI
528 AM CDT TUE APR 14 2015
UPDATED AVIATION PORTION FOR 12Z TAF ISSUANCE
.SHORT TERM...TODAY...TONIGHT...AND WEDNESDAY
ISSUED AT 308 AM CDT TUE APR 14 2015
THE LATEST RAP ANALYSIS AND SATELLITE/RADAR IMAGERY SHOW SPLIT FLOW
ACROSS NORTH AMERICA CONSISTING OF A RIDGE OVER THE ROCKIES...A
TROUGH OVER THE SOUTHERN PLAINS...AND CONVERGING UPPER FLOW ACROSS
THE EAST. THE WESTERN GREAT LAKES RESIDES DOWNSTREAM OF THE
RIDGE...WITH STRONG SUBSIDENCE LEADING TO CLEAR CONDITIONS ACROSS
THE REGION. THE AIRMASS ITSELF IS VERY DRY WITH PWATS FALLING BELOW
A QUARTER OF AN INCH. AS THE DRY SURFACE HIGH MOVES ACROSS THE
REGION...TEMPS AND HUMIDITIES ARE THE MAIN FORECAST CONCERNS THROUGH
WEDNESDAY.
TODAY...HIGH PRESSURE WILL DRIFT ACROSS THE REGION...WHICH WILL
PROMOTE CLEAR SKIES AND LIGHT WINDS. EVEN THOUGH UPSTREAM OBS SAW
DEWPOINTS CRASH INTO THE SINGLE DIGITS OVER MINNESOTA AND NORTH
DAKOTA IN THIS AIRMASS...SHOULD NOT HAVE THE KIND OF MECHANICAL
MIXING THIS REGION SAW YESTERDAY. HOWEVER...SHOULD SEE MIXING UP TO
800-750MB...WHICH SUPPORTS DROPPING DEWPOINTS INTO THE LOW TEENS UP
NORTH. COMBINED WITH HIGHS MAINLY IN THE MID TO UPPER 60S AWAY FROM
LAKE MICHIGAN...HUMIDITIES SHOULD FALL INTO THE TEENS. ELEVATED
FIRE WEATHER CONDITIONS WILL THEREFORE CONTINUE TODAY.
TONIGHT...HIGH PRESSURE WILL REMAIN PRESENT ACROSS THE REGION.
SHOULD SEE THIN CIRRUS INVADE FROM THE SOUTH AHEAD OF A WEAK UPPER
LOW ACROSS THE PLAINS. OTHERWISE QUIET...WITH LOWS FALLING INTO THE
UPPER 30S TO LOW 40S.
WEDNESDAY...CIRRUS WILL CONTINUE TO INVADE THE REGION AND BECOME
THICKER...WHICH WILL LEAD TO FILTERED SUNSHINE. THE SURFACE HIGH
WILL MOVE TO THE EASTERN GREAT LAKES...WHICH WILL CAUSE EAST TO
SOUTHEAST WINDS TO BECOME RELATIVELY STRONGER THAN TODAYS EXPECTED
SPEEDS. THE AIRMASS WILL MOISTURE SOME...BUT STILL WENT WITH THE
LOWEST GUIDANCE...WHICH PLACES RH VALUES BETWEEN 15 TO 25 PERCENT.
NO REPRIEVE FROM ELEVATED FIRE WEATHER CONDITIONS AS A RESULT.
.LONG TERM...WEDNESDAY NIGHT THROUGH MONDAY
ISSUED AT 308 AM CDT TUE APR 14 2015
CONTINUED WARM AND DRY CONDITIONS WILL CONTINUE INTO THE
WEEKEND...WITH ONLY A SMALL CHANCE OF SHOWERS FRIDAY INTO FRIDAY
EVENING. A MORE POTENT SYSTEM IS EXPECTED TO AFFECT THE REGION
EARLY NEXT WEEK.
FOR WEDNESDAY NIGHT...AN UPPER LEVEL DISTURBANCE WILL MOVE ACROSS THE
REGION. MODEL SOUNDINGS WERE BONE DRY...THUS REMOVED ANY MENTION OF
RAIN DESPITE STEEP MID LEVEL LAPSE RATES WITH THIS SYSTEM. ON
THURSDAY...MODEL SOUNDINGS STILL SHOW VERY DRY SOUNDINGS ALTHOUGH
NOT AS DRY AS TUESDAY AND WEDNESDAY SOUNDINGS. DID LOWER DEW
POINTS BY 3 TO 5 DEGREES MOST PLACES AS A STARTING POINT. WEAK
BOUNDARY EXPECTED TO MOVE ACROSS THE REGION ON FRIDAY...BRINGING
A SMALL CHANCE OF SHOWERS. MODELS DO SHOW MORE MOISTURE WITH THIS
FEATURE TO SUPPORT THE SMALL CHANCE OF SHOWERS.
HIGH PRESSURE WILL BUILD INTO THE REGION ON SATURDAY AND CONTINUE
INTO SUNDAY. VERY DRY CONDITIONS ARE EXPECTED AGAIN SATURDAY WITH
VERY LOW AFTERNOON RELATIVE HUMIDITY READINGS. ATTENTION THEN TURNS
TO UPPER LOW ACROSS THE CENTRAL UNITED STATES WILL INTERACT WITH
500MB TROUGH MOVING ACROSS SOUTHERN CANADA. THIS FEATURE SHOULD
ALLOW FOR LOW PRESSURE TO FORM AND BRING A CHANCE OF RAIN TO THE
AREA SUNDAY NIGHT AND MONDAY.
DID LOWER MIN TEMPERATURES WEDNESDAY NIGHT AND THURSDAY NIGHT...
WHILE RAISING MAX TEMPERATURES A DEGREE OR TWO ON MOST DAYS INTO
THE WEEKEND.
&&
.AVIATION...FOR 12Z TAF ISSUANCE
ISSUED AT 527 AM CDT TUE APR 14 2015
GOOD FLYING WEATHER WILL BE PRESENT THROUGH WEDNESDAY NIGHT THANKS
TO A VERY DRY HIGH PRESSURE SYSTEM MOVING ACROSS THE REGION.
&&
.GRB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM.....MPC
LONG TERM......ECKBERG
AVIATION.......MPC
FORECAST DISCUSSION FOR ROUTINE MORNING FORECAST ISSUANCE
.SHORT TERM...TODAY...TONIGHT...AND WEDNESDAY
ISSUED AT 308 AM CDT TUE APR 14 2015
THE LATEST RAP ANALYSIS AND SATELLITE/RADAR IMAGERY SHOW SPLIT FLOW
ACROSS NORTH AMERICA CONSISTING OF A RIDGE OVER THE ROCKIES...A
TROUGH OVER THE SOUTHERN PLAINS...AND CONVERGING UPPER FLOW ACROSS
THE EAST. THE WESTERN GREAT LAKES RESIDES DOWNSTREAM OF THE
RIDGE...WITH STRONG SUBSIDENCE LEADING TO CLEAR CONDITIONS ACROSS
THE REGION. THE AIRMASS ITSELF IS VERY DRY WITH PWATS FALLING BELOW
A QUARTER OF AN INCH. AS THE DRY SURFACE HIGH MOVES ACROSS THE
REGION...TEMPS AND HUMIDITIES ARE THE MAIN FORECAST CONCERNS THROUGH
WEDNESDAY.
TODAY...HIGH PRESSURE WILL DRIFT ACROSS THE REGION...WHICH WILL
PROMOTE CLEAR SKIES AND LIGHT WINDS. EVEN THOUGH UPSTREAM OBS SAW
DEWPOINTS CRASH INTO THE SINGLE DIGITS OVER MINNESOTA AND NORTH
DAKOTA IN THIS AIRMASS...SHOULD NOT HAVE THE KIND OF MECHANICAL
MIXING THIS REGION SAW YESTERDAY. HOWEVER...SHOULD SEE MIXING UP TO
800-750MB...WHICH SUPPORTS DROPPING DEWPOINTS INTO THE LOW TEENS UP
NORTH. COMBINED WITH HIGHS MAINLY IN THE MID TO UPPER 60S AWAY FROM
LAKE MICHIGAN...HUMIDITIES SHOULD FALL INTO THE TEENS. ELEVATED
FIRE WEATHER CONDITIONS WILL THEREFORE CONTINUE TODAY.
TONIGHT...HIGH PRESSURE WILL REMAIN PRESENT ACROSS THE REGION.
SHOULD SEE THIN CIRRUS INVADE FROM THE SOUTH AHEAD OF A WEAK UPPER
LOW ACROSS THE PLAINS. OTHERWISE QUIET...WITH LOWS FALLING INTO THE
UPPER 30S TO LOW 40S.
WEDNESDAY...CIRRUS WILL CONTINUE TO INVADE THE REGION AND BECOME
THICKER...WHICH WILL LEAD TO FILTERED SUNSHINE. THE SURFACE HIGH
WILL MOVE TO THE EASTERN GREAT LAKES...WHICH WILL CAUSE EAST TO
SOUTHEAST WINDS TO BECOME RELATIVELY STRONGER THAN TODAYS EXPECTED
SPEEDS. THE AIRMASS WILL MOISTURE SOME...BUT STILL WENT WITH THE
LOWEST GUIDANCE...WHICH PLACES RH VALUES BETWEEN 15 TO 25 PERCENT.
NO REPRIEVE FROM ELEVATED FIRE WEATHER CONDITIONS AS A RESULT.
.LONG TERM...WEDNESDAY NIGHT THROUGH MONDAY
ISSUED AT 308 AM CDT TUE APR 14 2015
CONTINUED WARM AND DRY CONDITIONS WILL CONTINUE INTO THE
WEEKEND...WITH ONLY A SMALL CHANCE OF SHOWERS FRIDAY INTO FRIDAY
EVENING. A MORE POTENT SYSTEM IS EXPECTED TO AFFECT THE REGION
EARLY NEXT WEEK.
FOR WEDNESDAY NIGHT...AN UPPER LEVEL DISTURBANCE WILL MOVE ACROSS THE
REGION. MODEL SOUNDINGS WERE BONE DRY...THUS REMOVED ANY MENTION OF
RAIN DESPITE STEEP MID LEVEL LAPSE RATES WITH THIS SYSTEM. ON
THURSDAY...MODEL SOUNDINGS STILL SHOW VERY DRY SOUNDINGS ALTHOUGH
NOT AS DRY AS TUESDAY AND WEDNESDAY SOUNDINGS. DID LOWER DEW
POINTS BY 3 TO 5 DEGREES MOST PLACES AS A STARTING POINT. WEAK
BOUNDARY EXPECTED TO MOVE ACROSS THE REGION ON FRIDAY...BRINGING
A SMALL CHANCE OF SHOWERS. MODELS DO SHOW MORE MOISTURE WITH THIS
FEATURE TO SUPPORT THE SMALL CHANCE OF SHOWERS.
HIGH PRESSURE WILL BUILD INTO THE REGION ON SATURDAY AND CONTINUE
INTO SUNDAY. VERY DRY CONDITIONS ARE EXPECTED AGAIN SATURDAY WITH
VERY LOW AFTERNOON RELATIVE HUMIDITY READINGS. ATTENTION THEN TURNS
TO UPPER LOW ACROSS THE CENTRAL UNITED STATES WILL INTERACT WITH
500MB TROUGH MOVING ACROSS SOUTHERN CANADA. THIS FEATURE SHOULD
ALLOW FOR LOW PRESSURE TO FORM AND BRING A CHANCE OF RAIN TO THE
AREA SUNDAY NIGHT AND MONDAY.
DID LOWER MIN TEMPERATURES WEDNESDAY NIGHT AND THURSDAY NIGHT...
WHILE RAISING MAX TEMPERATURES A DEGREE OR TWO ON MOST DAYS INTO
THE WEEKEND.
&&
.AVIATION...FOR 06Z TAF ISSUANCE
ISSUED AT 1044 PM CDT MON APR 13 2015
PATCHY MID LEVEL CLOUDS WILL DEPART NORTHERN WISCONSIN OVERNIGHT
OTHERWISE VFR CONDITIONS TO PREVAIL OVERNIGHT INTO TUESDAY.
&&
.GRB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM.....MPC
LONG TERM......ECKBERG
AVIATION.......TDH
AREA FORECAST DISCUSSION
NWS TAMPA BAY RUSKIN FL
430 AM EDT THU APR 16 2015
.SYNOPSIS...08Z WATER VAPOR AND H4 RAP ANALYSIS SHOW TWO DISTINCT
AND SEPARATE UPPER LEVEL FLOWS ACROSS NORTH AMERICA THIS MORNING.
THE NORTHERN STREAM FLOW HAS SHIFTED WELL TO THE NORTH AND NOW RUNS
IN A GENERALLY ZONAL CONFIGURATION TO THE NORTH OF THE US/CANADIAN
BORDER. A SECOND BELT OF SOUTHERN STREAM WESTERLIES CROSSES FROM THE
CENTRAL PACIFIC...OVER MEXICO...AND ACROSS THE GULF OF MEXICO INTO
THE SOUTHEASTERN CONUS/FL PENINSULA. THIS SOUTHERN STREAM FLOW IS
TRANSPORTING ABUNDANT MID/UPPER LEVEL MOISTURE INTO THE REGION PER
WV IMAGERY. BETWEEN THESE TO BELTS OF WESTERLIES...THE FLOW BECOMES
MUCH WEAKER...WITH A LARGE CUTOFF LOW NOW TRAPPED OVER THE INTER-
MOUNTAIN WEST...AND DOWNSTREAM RIDING OVER THE EASTERN CONUS. THE
UPPER LOW IS CURRENTLY CENTERED AND SPINNING NEAR THE 4-CORNERS
REGION...AND IS NOT SHOWN TO MOVE MUCH AT ALL DURING THE NEXT 24
HOURS BY THE MAJORITY OF THE AVAILABLE GUIDANCE.
WITHIN THE SOUTHERN STREAM FLOW WE SEE A SERIES OF WEAK IMPULSES
RIDING ALONG THE NORTHERN GULF COAST AHEAD OF AN 80-100KT JET
STREAK...EXTENDING OVER NORTHERN MEXICO TO THE WESTERN GULF OF
MEXICO. SYNOPTIC LIFT ASSOCIATED WITH THESE DISTURBANCES...AND ALONG
THE LEADING NOSE OF THE JET ARE FORCING PERIODIC PULSES OF
CONVECTION OVER THE NORTH-CENTRAL GULF OF MEXICO. SOME OF THIS LIFT
IS NOW BEGINNING TO REACH AS FAR EAST AS THE NE GOMEX WHERE HIGHER
LEVEL RADAR RETURNS ARE BEGINNING TO BLOSSOM SOUTH OF APALACHICOLA.
THE RAP/HRRR SEEM TO HAVE A DECENT HANDLE ON THIS ACTIVITY AND HAVE
FOLLOWED THEIR ENSEMBLE SOLUTION CLOSELY FOR THE RAIN CHANCES INTO
OUR NORTHERN MARINE ZONES/LEVY COUNTY THROUGH THE NEXT 4-8 HOURS.
AT THE SURFACE...HIGH PRESSURE WEDGING DOWN THE EASTERN SEABOARD
INTO THE SOUTHEAST CONUS HAS PUSHED A WEAK FRONTAL BOUNDARY DOWN
INTO NORTH-CENTRAL FLORIDA. THE BOUNDARY IS SUBTLE...BUT CAN BE
FOUND MOST EASILY BY SURFACE DEWPOINT ANALYSIS...WHERE SLIGHTLY
"DRIER" AIR HAS WORKED INTO AREAS NORTH OF THE I-4 CORRIDOR. THIS
QUASI-STATIONARY BOUNDARY IS LIKELY TO BE THE FOCUS (ALONG WITH
EVENTUAL SEA-BREEZE INTERACTIONS) FOR NUMEROUS SHOWERS AND STORMS
OVER PORTIONS OF THE REGION DURING THE SECOND HALF OF TODAY.
&&
.SHORT TERM (TODAY THROUGH FRIDAY)...
TODAY...
GENERALLY SPEAK THE MAJORITY OF THE SYNOPTIC LIFT AND ASSOCIATED
CONVECTION WITH THE SOUTHERN STREAM IMPULSES WILL REMAIN TO OUR
NORTHWEST TODAY. HOWEVER...THE SOUTHERN STREAM WILL CONTINUE TO
PROVIDE ABUNDANT COLUMN MOISTURE. THE SHOWERS AND STORMS IN OUR
FORECAST AREA WILL BE RELATED TO LOWER LEVEL FOCUS ALONG A QUASI-
STATIONARY FRONTAL BOUNDARY STRETCHED ACROSS NORTH-CENTRAL
FLORIDA...AND ITS EVENTUAL INTERACTION WITH ANY SEA-BREEZE THAT IS
ABLE TO BECOME ESTABLISHED. THE SEA-BREEZE SHOULD BE MOST DEFINED TO
THE SOUTH OF THE FRONTAL BOUNDARY FROM THE TAMPA BAY AREA...AND
ALONG THE SUN COAST. FOR THE MORNING HOURS...WILL BE TRACKING SHOWER
ACTIVITY CROSSING THE NORTHEAST GULF OF MEXICO AHEAD OF A LEADING
SOUTHERN STREAM IMPULSE. AS MENTIONED IN THE SYNOPSIS...THE LATEST
RAP/HRRR SEEM TO BE HANDLING THE CURRENT CONVECTION FAIRLY WELL AND
FOLLOWED THEIR SOLUTIONS THIS MORNING...BRINGING CHANCE POPS INTO
LEVY COUNTY. BOTH SHOW THIS ACTIVITY JUST BARELY REACHING LEVY...BUT
A SLIGHT SOUTHERN BIAS TO THE RADAR RETURNS COMPARED TO THE GUIDANCE
SUGGESTS THAT THEY MAY BE INITIALLY TOO FAR NORTH. A FEW OTHER
SHOWERS HAVE BEEN FORMING EARLY THIS MORNING OVER LEE COUNTY ALONG A
RESIDUAL OUTFLOW BOUNDARY FROM WEDNESDAY EVENING CONVECTION. THESE
SHOWERS ARE FINALLY PASSING OFF THE COAST INTO THE GULF.
TOWARD MIDDAY AND INTO THE AFTERNOON HOURS...CONVECTION ALLOWING
GUIDANCE AND PARAMETERIZED GUIDANCE ENSEMBLES ALL SUGGEST A RATHER
ACTIVE SECOND HALF OF THE DAY IN TERMS OF SHOWERS AND STORMS.
ACTUALLY AM VERY IMPRESSED WITH THE DEGREE OF AGREEMENT WITHIN THE
CONVECTION ALLOWING MODELS AS TO STORM INITIATION AND EVOLUTION.
APPEARS STORMS WILL BEGIN TO FIRE BY EARLY AFTERNOON ALONG THE
FRONTAL BOUNDARY GENERALLY ALONG THE I-4 CORRIDOR...AND BY THAT I
JUST MEAN CENTRAL FLORIDA. BY LATER IN THE AFTERNOON/EARLY
EVENING...APPEARS STORMS BEGIN TO ALIGN MORE NORTH TO SOUTH PARALLEL
TO THE COAST...WITH THE HEAVIEST ACTIVITY SHIFTING INTO OUR SOUTH-
CENTRAL ZONES...WHERE THE FRONTAL ZONES MOST ACTIVELY INTERACTS WITH
THE SUNCOAST SEA-BREEZE. THIS IS A TOUGH FORECAST ALONG THE
IMMEDIATE COAST AS THE SEA-BREEZE IS NOT STRONG TODAY...BUT MAY BE
JUST ENOUGH TO KEEP CONVECTION AWAY FROM THE BEACHES. FOR NOW...HAVE
THE HIGHEST POPS ALONG AND INLAND FORM I-75...BUT CERTAINLY
EXPECTING TO SEE SOME STORMS FURTHER WEST TO THE COAST...ESPECIALLY
FROM THE TAMPA BAY AREA...UP INTO PASCO/HERNANDO COUNTIES. STORMS
SHOULD EVENTUALLY EVOLVE FURTHER INLAND AND SOUTH AS THE EVENING
PROGRESSES...GIVEN THE FORECAST STORM MOTION BY THE GFS/NAM/RAP. OF
BIGGEST CONCERN LATER TODAY IS THIS STORM MOTION AND AVAILABLE
MOISTURE. NAM/GFS BOTH SHOWING PW VALUES AROUND 2" OVER SOUTH-
CENTRAL ZONES...WITH A SLOW STORM MOTION ONLY AROUND 5 KNOTS. THIS
IS CONCERNING FOR HEAVY RAIN POTENTIAL...ESPECIALLY GIVEN THAT
PORTIONS OF POLK/HIGHLANDS COUNTIES ALREADY RECEIVED SIGNIFICANT
RAINFALL THIS WEEK. WILL NEED TO MONITOR STORMS CLOSELY FOR
LOCALIZED FLOODING POTENTIAL. LOCAL HIRES GUIDANCE HAVE ALSO BEEN
SHOWING FOR SEVERAL RUNS FAIRLY IMPRESSIVE UPDRAFT VELOCITIES WITH
THE ACTIVITY LATER TODAY...ON THE ORDER OF 15 M/S. THESE ARE DECENT
VALUES FOR SEA-BREEZE STORMS...ESPECIALLY THIS TIME OF YEAR. GIVEN
THE AVAILABLE MOISTURE AND POTENTIAL FOR POTENT UPDRAFTS...PRECIP
LOADING AND DOWNDRAFT WIND GUST THREAT WITH THE STRONGER STORMS WILL
ALSO NEED TO BE MONITORED CLOSELY.
CONVECTION IS LIKELY TO LINGER WELL INTO THE LATE EVENING HOURS OVER
OUR SOUTH-CENTRAL ZONES GIVEN THE NEARBY FRONTAL FOCUS...BUT SHOULD
BE ENDING EARLIER OVER THE REST OF THE FORECAST AREA. THE SECOND
HALF OF THE NIGHT APPEARS MUCH QUIETER...AS WOULD BE EXPECTED WITH
THE LOSS OF DIURNAL HEATING. ONE IMPULSE AFTER ANOTHER WILL BE
MOVING ALONG THE NORTHERN GULF COAST...AND ANY OF THESE MAY THREATEN
OUR FAR NORTHERN NATURE COAST ZONES (LEVY/CITRUS) WITH A ROUND OF
SHOWER. CURRENTLY THE GUIDANCE SEEMS TO GRABBING ONTO ANOTHER ONE OF
THESE ROUNDS LATE TONIGHT. THE IMPULSES ARE SO SUBTLE AND DEPENDENT
ON JUST THE RIGHT DOWNSTREAM CONVECTIVE ACTIVITY...THAT FEEL GOING
TO AGGRESSIVE WITH POPS AT THIS POINT IS UNNECESSARY. WILL LET THE
DAYSHIFT REEVALUATE FOR THESE NORTHERN ZONES AFTER 06Z.
FRIDAY... BOUNDARY BEGINS TO DECAY...WITH A WEAK GRADIENT ALLOWING
FOR A MORE UNIFORM SEA-BREEZE TO DEVELOP ALONG THE FL WEST COAST.
1000-700MB FLOW FROM THE W/NW WOULD SUGGEST THIS SEABREEZE MOVE
INLAND MORE QUICKLY...WITH EAST/WEST COAST SEA-BREEZE INTERACTIONS
OCCURRING OVER OUR FAR INLAND ZONES OR EVEN OVER TOWARD THE I-95
CORRIDOR. WITH THIS IN MIND...OVERALL RAIN CHANCES APPEAR LOWER FOR
THE I-75 CORRIDOR...ESPECIALLY THIS CORRIDOR SOUTH OF THE TAMPA BAY
AREA. HIGHEST POPS 50-60% WILL THEREFORE EXIST WELL INLAND OVER
SOUTHERN AREAS...AND ALSO ACROSS THE NATURE COAST IN CLOSER
PROXIMITY TO ANY PASSING SYNOPTIC SUPPORT.
&&
.LONG TERM (SATURDAY THROUGH NEXT WEDNESDAY)...
THE PERIOD BEGINS WITH AN UPPER LEVEL CUT-OFF LOW NEAR THE FOUR
CORNERS REGION AND RIDGING FROM THE GULF OF MEXICO TO NEAR THE GREAT
LAKES. A FRONTAL BOUNDARY STRETCHES ALONG THE EASTERN GULF COAST AND
THROUGH NORTHERN FL WHILE MID-ATLANTIC HIGH PRESSURE RIDGES SOUTH
INTO FL WITH A WEAK GRADIENT. THROUGH THE WEEKEND THE CUT-OFF LOW
TRACKS UP TO THE GREAT LAKES...WITH A SURFACE LOW FORMING AND
TRAILING A COLD FRONT THAT ARCS THROUGH THE SOUTHEAST U.S. AND INTO
THE GULF...AND OPENS INTO A BROAD TROUGH DOWN INTO THE GULF. THE
UPPER RIDGE SLIDES OFF THE EASTERN SEABOARD WHILE THE FRONTAL
BOUNDARY LIFTS NORTHWARD. A MOIST AIRMASS REMAINS IN PLACE AS THE
FRONTAL BOUNDARY DEPARTS AND LOW LEVEL FLOW SHIFTS FROM EASTERLY TO
SOUTHERLY...BUT WITH AFTERNOON SEAS BREEZES..AND INCREASE IN
STRENGTH AS THE COLD FRONT MOVES INTO THE GULF. THIS WILL RESULT IN
SHOWERS AND THUNDERSTORMS WITH THE BEST COVERAGE IN THE
AFTERNOONS...IN THE CHANCE RANGE.
FOR MON-WED THE UPPER LEVEL TROUGH SLOWLY SHIFTS EAST...DOMINATING
THE EASTERN U.S. WHILE THE SURFACE LOW EJECTS INTO CANADA AND DRAGS
THE COLD FRONT OUT OVER THE ATLANTIC...BUT WITH THE SOUTHERN END
SLOWLY SAGGING SOUTHWARD ACROSS FL. SOUTHERLY AND SOUTHWESTERLY FLOW
WILL INCREASE EARLY IN THE PERIOD PROVIDING ADDITIONAL MOISTURE
WHICH WITH THE APPROACHING FRONT WILL RESULT IN SHOWERS AND
THUNDERSTORMS..WITH CHANCE TO LIKELY POPS MON AS THE FRONT PUSHES
INTO THE AREA. RAIN CHANCES BEGINS TO TREND DOWN TUE-WED AS THE
FRONT SLIDES SOUTH AND WEAKENS.
TEMPERATURES START OFF WELL ABOVE NORMAL BUT GRADUALLY DROP BY MID
WEEK. HIGHS DECREASE TO NEAR NORMAL BUT THE OVERNIGHT LOWS WILL
CONTINUE ON THE WARM SIDE.
&&
.AVIATION... VFR CONDITIONS PREVAILING ACROSS WEST-CENTRAL AND MOST
OF SOUTHWEST FLORIDA EARLY THIS MORNING. HAVE SEEN A FEW SHOWERS
AROUND KFMY/KRSW WITH BRIEF MVFR CIGS...HOWEVER THIS ACTIVITY SHOULD
DIMINISH BEFORE SUNRISE. AVIATION CONCERNS TODAY WILL CENTER AROUND
THE DEVELOPMENT OF SCT TO NMRS SHOWERS AND THUNDERSTORMS FOR THE
AFTERNOON/EVENING HOURS. THE GREATEST COVERAGE OF STORMS WILL BE
INLAND FROM THE I-75 CORRIDOR AFTER 17Z...ALTHOUGH EVEN TERMINALS
ALONG I-75 WILL HAVE THE POTENTIAL FOR A STORM.
&&
.MARINE... A WEAK FRONTAL BOUNDARY WILL DIP SOUTH INTO NORTHERN
FLORIDA AND THE FAR NORTHEAST GULF OF MEXICO TODAY AND REMAIN IN
PLACE THROUGH FRIDAY. THIS BOUNDARY WILL THEN DECAY FRIDAY NIGHT
INTO SATURDAY AS WEAK HIGH PRESSURE BUILDS SOUTH INTO THE REGION
FROM THE NORTH. WINDS AND SEAS WILL REMAIN LOW THROUGH SATURDAY WITH
SPEEDS GENERALLY LESS THAN 10-15 KNOTS. THE BEST POTENTIAL FOR
DEFINED SEA-BREEZE DEVELOPMENT NEAR THE COAST THE NEXT TWO DAYS WILL
BE TO THE SOUTH OF THE FRONTAL BOUNDARY...MAINLY SOUTH OF TARPON
SPRINGS.
&&
.FIRE WEATHER... A WEAK FRONT WILL DIP INTO NORTHERN FLORIDA TODAY
AND THEN REMAIN NEARLY STATIONARY THROUGH FRIDAY. NO SIGNIFICANT
FIRE WEATHER CONCERNS ARE EXPECTED THROUGH THE END OF THE WEEK.
RELATIVE HUMIDITY VALUES WILL REMAIN WELL ABOVE CRITICAL LEVELS.
SHOWERS AND THUNDERSTORMS ARE EXPECTED TO BECOME RATHER NUMEROUS
OVER INTERIOR CENTRAL AND SOUTH-CENTRAL ZONES LATER THIS AFTERNOON
AND EVENING WITH MORE SCATTERED VARIETY STORMS ELSEWHERE. SHOWERS
AND STORMS SHOULD AGAIN BE MOST NUMEROUS WELL INLAND FROM THE COAST
ON FRIDAY.
&&
.PRELIMINARY POINT TEMPS/POPS...
TPA 86 72 85 71 / 50 30 40 20
FMY 89 71 88 71 / 40 40 20 10
GIF 87 69 86 69 / 80 50 60 20
SRQ 83 71 83 70 / 30 20 30 20
BKV 86 67 85 66 / 60 40 50 20
SPG 86 74 84 73 / 40 20 30 20
&&
.TBW WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
GULF WATERS...NONE.
&&
$$
SYNOPSIS/SHORT TERM/MARINE/AVIATION/FIRE WX...MROCZKA
LONG TERM/DECISION SUPPORT SERVICES...RUDE
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
1257 AM CDT THU APR 16 2015
.UPDATE...
758 PM CDT
HAVE ONLY MADE SLIGHT ADJUSTMENTS TO THE REST OF TONIGHT FORECAST.
A PICTURESQUE SKY OF VIRGA FROM CIRRUS/HIGH BASED ALTOCU OUT OUR
WINDOW AT SUNDOWN AND SHARED WITH US BY SEVERAL OF OUR SOCIAL
MEDIA FOLLOWERS. THE RAOB FROM DVN AT 00Z INDICATES A WARM
ADVECTION PROFILE FROM JUST OFF THE DECK ALL THE WAY UP...WITH
MOISTENING OCCURRING 15000 FT AND ABOVE ALONG WITH SOME MODEST
LAPSE RATES...THOUGH VERY DRY STILL BELOW THAT. AT ILX THIS
SATURATED LAYER IS DOWN TO 6000 FT WITH PRONOUNCED DRYING BELOW.
WATER VAPOR IMAGERY INDICATES A COMPACT BUT MOISTURE-STARVED
CIRCULATION IN SOUTHWEST ILLINOIS ADVANCING NORTHEAST...WITH SOME
SHOWER ACTIVITY REACHING THE GROUND AHEAD OF IT IN THE CENTRALIA
AND EFFINGHAM AREAS. TIMING THIS CORRIDOR OF FORCING WOULD MOVE
IT INTO THE SOUTHERN FORECAST AREA AROUND 11 PM. RAP AND NAM
FORECASTS INDICATE MOVE VEERED/SOUTHERLY PROFILES DOWN TO
900MB...WITH FORECAST MOISTURE TRANSPORT AND ADIABATIC LIFT
LIKELY TO AID IN SATURATION FOR AT LEAST SCATTERED LIGHT SHOWERS
ACROSS THE EASTERN FORECAST AREA. THAT IS IN LINE WITH GOING
FORECAST AND FOR THE MOST PART CURRENT HIGH-RES GUIDANCE. JUST
HAVE SLOWED THE START TIME OF POPS DOWN SLIGHTLY...BUT ALL IN ALL
A NEGLIGIBLE CHANGE TO WORDING FOR MOST AREAS. RAINFALL AMOUNTS
UNDER 0.15 OF AN INCH LOOK GOOD...WITH MOST OF NORTH CENTRAL
ILLINOIS NOT SEEING MORE THAN A TRACE.
GOING TEMPERATURES AND IMPROVING RELATIVE HUMIDITY VALUES LOOK ON
TRACK.
MTF
&&
.SHORT TERM...
339 PM CDT
THROUGH FRIDAY...
BETTER AGREEMENT BETWEEN DETERMINISTIC MODELS AND THEIR ENSEMBLE
COUNTERPARTS IS PROVIDING INCREASED FORECAST CONFIDENCE FOR THE
REMAINDER OF THE WEEK AND INTO EARLY NEXT WEEK. THE PRIMARY UPPER
LEVEL FEATURES BEING TRACKED INCLUDE A LARGE SOUTHERN STREAM LOW
DIGGING INTO THE FOUR CORNERS...A DOWNSTREAM RIDGE WITH EMBEDDED
SHORTWAVES...AND A CLOSED LOW PROJECTED TO DEVELOP IN A DEEPENING
NORTHERN STREAM TROUGH AND MERGE LATE IN THE WEEKEND WITH THE SYSTEM
THAT FINALLY WILL BE LIFTING OUT OF THE DESERT SOUTHWEST. AT LOWER
LEVELS...MODELS AGREE IN LIFTING A WEAK SURFACE TROUGH ACROSS THE
AREA TONIGHT AND IN TAKING A MORE DEVELOPED LOW PRESSURE SYSTEM
ACROSS THE AREA SATURDAY NIGHT INTO SUNDAY IN CONJUNCTION WITH THE
MERGING UPPER TROUGHS.
FOR THIS EVENING AND OVERNIGHT...THE AREA OF SHOWERS AND ISOLATED
TSRA STRETCHING FROM NORTHWEST IA ACROSS MO AND INTO KY IS
CORRELATED WITH A GRADIENT OF ENHANCED MOISTURE FLUX DEPICTED IN THE
RAP. AS THIS GRADIENT LIFTS NORTH...PRECIP CHANCES INCREASE TOWARD
MIDNIGHT AND ESPECIALLY IN THE PREDAWN HOURS. FORECAST SOUNDINGS
TREND TOWARD MOIST ADIABATIC AND DEEPLY SATURATED...SO PWATS
INCREASE CONSIDERABLY OVERNIGHT BUT INSTABILITY IS TALL AND SKINNY.
BETTER CHANCE OF TSRA WILL LIKELY REMAIN SOUTH AND EAST OF THE METRO
AREA.
DURING THE DAYTIME THURSDAY AND ESPECIALLY INTO THURSDAY
NIGHT...HEIGHTS INCREASE ALOFT AS THE UPPER SHORTWAVES MOVE EAST OF
THE AREA AND LOWER LEVELS DRY OUT. WILL CARRY LOW CHANCE POPS INTO
THE THURSDAY MORNING HOURS AND EARLY AFTERNOON BUT KEEP THURSDAY
NIGHT AND FRIDAY DRY.
LENNING
&&
.LONG TERM...
339 PM CDT
FRIDAY NIGHT THROUGH WEDNESDAY...
AFTER ANOTHER QUIET DAY ON SATURDAY...THE MERGING NORTHERN AND
SOUTHERN STREAM TROUGHS AND DEVELOPMENT OF A CLOSED SURFACE LOW IN
THE LEE OF THE ROCKIES WILL BRING INCREASED PRECIP CHANCES TO THE
AREA FOR SATURDAY NIGHT AND SUNDAY. WITH THE CENTER OF THE SURFACE
LOW PASSING SOUTH OF THE AREA ACROSS CENTRAL ILLINOIS...AM SEEING
GOOD SUPPORT FOR SHOWERS SATURDAY NIGHT AND EARLY SUNDAY BUT NOT
MUCH IN THE WAY OF CONVECTION UNTIL THE LOW PUSHES A WARM FRONT
THROUGH THE AREA AROUND MIDDAY AND BRIEFLY MOVES THE AREA INTO
THE WARM SECTOR AHEAD OF THE TRAILING COLD FRONT. THE PEAK PERIOD
FOR TSRA WOULD APPEAR TO BE SUNDAY AFTERNOON AND EVENING.
AFTER THE SURFACE LOW LIFTS WELL NORTH OF THE AREA SUNDAY NIGHT
INTO MONDAY...CYCLONIC FLOW ALOFT AND RESIDUAL BOUNDARY LAYER
MOISTURE MAY CONTINUE TO SUPPORT THE CHANCE OF SHOWERS INTO
MONDAY...BUT A RIDGE OF HIGH PRESSURE WILL BEGIN TO BUILD FROM THE
PLAINS INTO THE SOUTHERN GREAT LAKES BY TUESDAY...AGAIN DRYING
THINGS OUT FOR AT LEAST THE FIRST HALF OF THE WEEK.
LENNING
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 06Z...
* EAST WINDS ARND 10 KT OVERNIGHT.
* POTENTIAL FOR SHOWERS TONIGHT/EARLY THURSDAY MORNING.
* A PERIOD OF MVFR/IFR LIKELY EARLY THURSDAY.
* NORTHEAST WINDS 10 KT OR LESS THURSDAY.
KREIN
//DISCUSSION...UPDATED 06Z...
THE EAST LOW LEVEL FLOW WAS MAINTAINING ADVECTION OF DRY LOW
LEVEL AIR ACROSS MUCH OF NORTHERN ILLINOIS...WHILE SOUTH-
SOUTHEAST WINDS ALOFT WERE PULLING MOISTURE NORTHWARD ALOFT OVER
NORTHWESTERN INDIANA AS A WEAK MID LEVEL CIRCULATION MOVES NWD
ALONG THE IL/IN BORDER. SCT SHOWERS ASSOCIATED WITH THE MID LEVEL
CIRCULATION ARE SLOWLY MOVING NWD INTO NWRN IN...BUT ARE HAVING
SOME TROUBLE OVERCOMING THE DRY LOW LEVEL AIR...SO IT WILL STILL
TAKE SOME TIME FOR RAIN TO REACH THE SURFACE. STILL FEEL THAT
THERE IS SOME POTENTIAL FOR SHRA AT THE CHICAGO AREA
TERMINALS...ESPECIALLY GYY AND MDW...BUT ORD/DPA STILL HAVE SOME
POTENTIAL AS WELL. WILL MAINTAIN THE VCSH AT RFD...THOUGH THE
POTENTIAL FOR ANY PCPN REACHING THE GROUND THERE IS DIMINISHING AS
THE MID LEVEL CIRCULATION SHOULD TAKE A TURN TO THE NORTHEAST
LATE TONIGHT. WITH THE ARRIVAL OF SHOWERS OVER THE EASTERN
TERMINALS...FORECAST SOUNDINGS INDICATE A PERIOD OF MVFR... AND
POSSIBLY IFR CIGS EARLY THURSDAY MORNING. LIGHT WINDS BY THAT
TIME SUGGEST MVFR CIGS MAY BE A LITTLE SLOW TO LIFT/SCATTER...AND
MAY NOT IMPROVE TO VFR UNTIL THURSDAY AFTERNOON.
WEAK GRADIENT AND LIGHT WINDS THURSDAY ARE EXPECTED TO BECOME
NORTHEAST NEAR LAKE MICHIGAN...WHILE INLAND SITES DPA AND RFD ARE
LIKELY SEE LIGHT NORTH-NORTHWEST WINDS.
KREIN
//ORD AND MDW CONFIDENCE...UPDATED 06Z...
* MEDIUM CONFIDENCE IN SHRA COVERAGE/TIMING OVERNIGHT AND EARLY
THURSDAY.
* MEDIUM-HIGH CONFIDENCE IN PERIOD OF MVFR CIGS...MEDIUM IN IFR.
* LOW-MEDIUM CONFIDENCE IN TRENDS THURSDAY.
KREIN
//OUTLOOK FOR ORD/MDW FOR 12Z FRIDAY-12Z WEDNESDAY...UPDATED 00Z...
FRIDAY...VFR. LIGHT VARIABLE WINDS BECOMING SOUTHEAST.
SATURDAY...VFR. CHANCE OF SHRA WITH MVFR POSSIBLE SATURDAY NIGHT.
NORTHEAST WINDS.
SUNDAY...CHANCE SHRA. MVFR POSSIBLE. EAST-NORTHEAST WINDS.
MONDAY...CHANCE SHRA EARLY. MVFR IMPROVING TO VFR. WEST-NORTHWEST
WINDS.
TUESDAY...VFR. CHANCE SHRA TUES NGT. WEST WINDS.
RATZER
&&
.MARINE...
153 PM CDT
A RIDGE OF HIGH PRESSURE CENTERED JUST TO THE NORTHEAST OF THE
GREAT LAKES IS ALLOWING FOR LIGHTER WINDS ACROSS THE LAKE
TODAY...BUT WITH THE HIGHEST WINDS OF 10 TO 20 KT BEING OBSERVED
OVER THE SOUTHERN HALF. EASTERLY WINDS OF 10 TO 20 KT WILL
CONTINUE TONIGHT FOR THE SOUTH HALF AND THE NEARSHORE AS A TIGHTER
PRESSURE GRADIENT REMAINS...AND WITH MORE STABLE CONDITIONS
HELPING TO KEEP WIND SPEEDS DOWN. SURFACE PATTERN BEGINS TO RELAX
LATER TONIGHT INTO THURSDAY MORNING WHILE SPEEDS DIMINISH AND WITH
WINDS LIKELY BECOMING VARIABLE DURING THE DAY THURSDAY. THIS
RELAXED PATTERN LOOKS TO PERSIST THROUGH THE END OF THE WORK
WEEK...WITH GENERALLY LIGHTER SPEEDS IN PLACE.
RODRIGUEZ
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...NONE.
&&
$$
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AREA FORECAST DISCUSSION
NWS JACKSON KY
213 AM EDT THU APR 16 2015
.UPDATE...
ISSUED AT 213 AM EDT THU APR 16 2015
SHOWERS ARE BEGINNING TO MOVE INTO THE LAKE CUMBERLAND REGION IN
RESPONSE TO AN APPROACHING UPPER LEVEL SHORTWAVE. SHOWER COVERAGE
IS EXPECTED TO GRADUALLY INCREASE THROUGH THE MORNING AS THIS
SHORTWAVE MOVES THROUGH THE AREA. NEAR TERM MODELS INDICATE TWO
WAVES OF SHOWERS AND A FEW THUNDERSTORMS TODAY AND POPS WERE
ADJUSTED TO ACCOUNT FOR THE MORNING PRECIP...FOLLOWED BY A BRIEF
LULL AND THEN ANOTHER UPTICK IN SHOWERS AND A FEW THUNDERSTORMS IN
THE AFTERNOON. WE SHOULD NOT BE ABLE TO ACHIEVE THE AMOUNT OF
INSTABILITY CURRENTLY FOUND OVER WESTERN AND CENTRAL TENNESSEE
TODAY...SO DO NOT ANTICIPATE THE STRONG TO OCCASIONALLY SEVERE
THUNDERSTORMS FOUND THERE TO BE ABLE TO MAINTAIN THERE STRENGTH
THIS FAR NORTH AND EAST.
UPDATE ISSUED AT 941 PM EDT WED APR 15 2015
GENERALLY ISOLATED SHOWERS CONTINUE ACROSS THE CWA LATE THIS
EVENING..WITH MORE SCATTERED ACTIVITY ACROSS THE NORTH CENTRAL
PORTION OF THE STATE ALONG A WEAK BOUNDARY. HEAVIER SHOWERS AND
THUNDERSTORMS REMAIN WELL TO OUR SOUTHWEST ACROSS WESTERN
TN...CLOSER TO THE SURFACE LOW PRESSURE CENTER LOCATED NEAR THE
SAME AREA. THIS LOW WILL CONTINUE TO SLOWLY SHIFT NE THROUGHOUT
THE NIGHT...REACHING FAR WESTERN KY BY 12Z TOMORROW. THIS MAY
ALLOW SOME MORE SHOWERS AND POSSIBLY EVEN AN ISOLATED
THUNDERSTORM TO DEVELOP AND MOVE INTO THE CWA LATER IN THE NIGHT
AND EARLY IN THE MORNING. BUT IN THE MEANTIME...IT LOOKS AS THINGS
ARE STARTING TO SETTLE DOWN ACROSS THE REGION.
CONTINUED CLOUD COVER...A HIGH AMOUNT OF MOISTURE...AND LIGHT
WINDS...WILL HELP TO MODERATE THE TEMPERATURES OVERNIGHT. CURRENT
READINGS OF UPPER 50S HAVE BEEN INCORPORATED INTO THE NEAR TERM
FORECAST...WITH ONLY A 3 TO 5 DEGREE DIURNAL FALL INTO THE LOW TO
MID 50S EXPECTED BY MORNING.
&&
.SHORT TERM...(THIS EVENING THROUGH THURSDAY NIGHT)
ISSUED AT 340 PM EDT WED APR 15 2015
18Z SFC ANALYSIS SHOWS THAT THE INVERTED TROUGH AXIS HAS SHIFTED
EAST TO ALONG THE SPINE OF THE APPALACHIANS WITH THE LOWER
MISSISSIPPI VALLEY LOW/S WARM FRONT LIFTING NORTH INTO KENTUCKY.
THE LIGHT PCPN AND OVERCAST CONDITIONS HAS KEPT MOST OF THE AREA
ON THE COOL SIDE TODAY...ESPECIALLY OUTSIDE OF THE CUMBERLAND
VALLEY. HOWEVER...THINNING CLOUDS AND A BREAK IN THE LIGHT RAIN
SHOULD ALLOW FOR SOME DECENT TEMP RISES OVER THE NEXT COUPLE OF
HOURS FOR ALL BUT THE FAR NORTHEAST. READINGS CURRENTLY VARY FROM
THE UPPER 50S IN THE NORTHEAST TO THE UPPER 60S IN THE SOUTH WHILE
DEWPOINTS RANGE FROM NEAR 60 SOUTH TO THE UPPER 40S IN THE FAR
NORTH. WINDS ARE GENERALLY FROM THE EAST TO NORTHEAST AT 10 TO 15
MPH OVER THE NORTHERN HALF OF THE AREA WHILE THEY ARE A BIT
LIGHTER AND MORE VARIABLE TO THE SOUTH. THE LIFTING WARM FRONT
MAY REINITIATE SHOWERS LATER IN THE AFTERNOON INTO THE EVENING...
PER THE LATEST HRRR AND NAM12...BUT RIGHT NOW THE RADAR SCOPE IS
PRETTY CLEAN. SHOULD CONVECTION REDEVELOP...SOME THUNDER MAY EVEN
BE POSSIBLE GIVEN THE RISING TEMPS/INSTABILITY...ESPECIALLY IN
THE SOUTH.
THE MODELS ARE IN GOOD AGREEMENT ALOFT THROUGH THE SHORT TERM
PORTION OF THE FORECAST AS A FEW CLUSTERS OF MID LEVEL ENERGY WILL
BRUSH KENTUCKY AS THEY MOVE INTO THE OHIO VALLEY TONIGHT ON THE
NORTHWEST FRINGE OF A BUILDING RIDGE. THE RIDGE FLATTENS A BIT ON
THURSDAY AS ADDITIONAL ENERGY PASSES THROUGH NORTHERN KENTUCKY
THAT AFTERNOON/OVERNIGHT AND INTO FRIDAY MORNING. TO THE WEST...A
SLOW MOVING CLOSED LOW SPINS ESSENTIALLY IN PLACE NEAR THE FOUR
CORNERS REGION OF THE COUNTRY...SERVING AS A SOURCE REGION FOR
ENERGY ABLE TO ESCAPE AND DRIFT EAST IN THE SOUTHERN STREAM THAT
CONTINUES TO DOMINATE KENTUCKY/S WX. GIVEN THE GENERAL MODEL
AGREEMENT HAVE FOLLOWED A BLEND WITH A LEAN TOWARD THE HRRR AND
NAM12 FOR WEATHER SPECIFICS DUE TO THEIR HIGHER RESOLUTION...
THOUGH CURRENT CONDITIONS AND TRENDS ARE ALSO OF HIGH RELEVANCE
INTO THE NEAR TERM PORTION OF THE FORECAST.
SENSIBLE WEATHER WILL FEATURE A POTENTIAL FOR SHOWERS INTO THE
EVENING AS THE SFC FRONT LIFTS NORTHEAST THROUGH THE AREA WITH A
THUNDERSTORM POSSIBLE...AS WELL. ADDITIONAL CONVECTION WILL BE
POSSIBLE INTO THURSDAY MORNING WITH THE SFC LOW TO THE SOUTHWEST
APPROACHING. THIS WILL LIKELY LIFT ANOTHER BOUNDARY THROUGH
EASTERN KENTUCKY DURING THE DAY WITH SHOWERS AND STRAY STORMS A
GOOD BET. THE PCPN CHANCES WILL DIMINISH INTO FRIDAY MORNING BUT
CANNOT GO DRY ATTM GIVEN THE ENVIRONMENT. THIS REMAINS A LOW
CONFIDENCE FORECAST WITH RESPECT TO SPECIFIC DETAILS BUT IN
GENERAL YOU CAB BANK ON RELATIVELY WARM AND MOIST CONDITIONS
CONTINUING.
USED THE SHORTBLEND GUIDANCE AS A STARTING POINT FOR T/TD/WIND
GRIDS THROUGH THE FIRST 18-24 HOURS OF THE FORECAST FOLLOWED BY
THE SUPERBLEND. GIVEN THE HUMID CONDITIONS MADE ONLY MINOR TERRAIN
BASED ADJUSTMENTS TO TEMPERATURES TONIGHT AND THURSDAY NIGHT. AS
FOR POPS...ENDED UP ON THE LOW SIDE OF MOS GUIDANCE TONIGHT AND
THURSDAY...BUT IN LINE FOR THURSDAY NIGHT.
.LONG TERM...(FRIDAY THROUGH WEDNESDAY)
ISSUED AT 340 PM EDT WED APR 15 2015
THE EXTENDED PERIOD WILL BE DOMINATED BY A LARGE CLOSED LOW OVER THE
FOUR CORNERS REGION WITH SOME SLIGHT RIDGING OVER THE EASTERN CONUS.
AFTER A SHORT WAVE IMPULSE...PROVIDING A ROUND OF RAINFALL TO THE
REGION...PUSHES THROUGH THE TN AND OH VALLEYS FRIDAY MORNING...
FRIDAY EVENING INTO SATURDAY MORNING WILL BE MOSTLY DRY. ON
SATURDAY...ANOTHER IMPULSE MOVING ALONG THE NORTHERN STREAM PUSHES
EWD TOWARDS THE GREAT LAKES REGION. AT THE SAME TIME...THE CLOSED
LOW EJECTS EWD AS WELL. THE ENERGY FROM THE CLOSED LOW THEN FEEDS
INTO THE NORTHERN STREAM TROUGH AND HELPS DEEPEN/INTENSIFY IT. THIS
SYSTEM WILL PROVIDE THE BEST CHANCE FOR A SIGNIFICANT AMOUNT OF
RAINFALL FOR EASTERN KENTUCKY IN THE SATURDAY NIGHT THROUGH MONDAY
MORNING TIME FRAME. THIS RAINFALL HAS THE POSSIBILITY OF BREAKING
THE JKL/S ALL-TIME APRIL RAINFALL RECORD...CURRENTLY WE HAVE HAD THE
SECOND WETTEST APRIL ON RECORD. IN FACT...THIS SYSTEM WILL SPREAD
PRECIP FROM THE NORTHERN MISSISSIPPI VALLEY REGION ACROSS MOST OF
THE EASTERN CONUS THROUGH TUESDAY. CLOSER TO HOME...TUESDAY AND
WEDNESDAY LOOKS TO BE FAIRLY QUIET...COOLER...AND DRY AS THE UPPER
LEVELS TRANSITION TO MORE OF A ZONAL FLOW PATTERN.
GFS AND ECMWF MODELS ACTUALLY HAVE GOOD AGREEMENT WITH THE EVOLUTION
OF THIS MAJOR SYSTEM. ADDITIONALLY...THERE LOOKS TO BE A STRONG
SURGE OF GULF MOISTURE WITH PW VALUES REACHING 1.50 INCHES IN SOME
LOCATIONS WITH SOME INSTABILITY PRESENT. THEREFORE...HAVE DECIDED TO
INCLUDED SLIGHT CHANCES OF THUNDER THROUGHOUT THE EXTENDED PERIOD
WITH LIKELY THUNDER DURING THE SUNDAY AFTERNOON THROUGH MONDAY
MORNING TIME FRAME. PROBABLY COULD HAVE UPPED POPS TO GO CATEGORICAL
ON SUNDAY/MONDAY MORNING BUT HAVE REMAINED CONSISTENT WITH NEIGHBORS
FOR NOW AND KEPT LIKELY POPS IN THE GRIDS. ALL IN ALL...BASED ON THE
CONTINUED WET PATTERN...THE MAIN CONCERN DURING THE EXTENDED PERIOD
WILL BE HEAVY RAINFALL WITH LOCALIZED FLOODING CONCERNS...ESPECIALLY
IN AREAS THAT RECEIVE SEVERAL ROUNDS OF RAINFALL AND WHERE RIVERS
AND CREEKS ARE STILL RUNNING HIGH.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z THURSDAY NIGHT)
ISSUED AT 213 AM EDT THU APR 16 2015
LOW LEVEL SOUTHEASTERLY FLOW HAS WORKED TO SCOUR OUT THE EARLIER
LOW CLOUDS WITH MAINLY VFR CONDITIONS FOUND ACROSS EAST KENTUCKY
AT THIS TIME. AN APPROACHING UPPER LEVEL DISTURBANCE WILL BRING AN
INCREASE IN SHOWERS...AND MAYBE A THUNDERSTORM...THROUGH THE
MORNING HOURS...WITH MVFR CONDITIONS LIKELY FOR A PERIOD OF TIME.
THE MORNING SHOWERS SHOULD SHIFT TO OUR EAST DURING THE MIDDAY
HOURS WITH VFR CONDITIONS EXPECTED AND JUST WIDELY SCATTERED
SHOWERS LEFT BEHIND. NEAR TERM MODELS THEN INDICATE ADDITIONAL
FORCING DURING THE AFTERNOON HOURS AND THIS MAY PRODUCE ANOTHER
UPTICK IN SHOWER COVERAGE WITH A THUNDERSTORM OR TWO ALSO
POSSIBLE. STILL UNSURE HOW WIDESPREAD THAT SECOND ROUND WILL
BECOME SO JUST KEPT WITH A VCSH MENTION FROM MIDDAY ON IN THE
TAFS FOR RIGHT NOW.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...JMW/ABE
SHORT TERM...GREIF
LONG TERM...JVM
AVIATION...ABE
AREA FORECAST DISCUSSION
NWS NEW ORLEANS LA
414 AM CDT THU APR 16 2015
.SHORT TERM...
LITTLE CHANGE IN THINKING FROM THE PREVIOUS FORECAST...AS THE AREA
REMAINS UNDER THE INFLUENCE OF A BROAD REGION OF ENHANCED OMEGA
THROUGH SATURDAY AS A SLOW MOVING UPPER LEVEL TROUGH OVER THE FOUR
CORNERS DRIFTS THROUGH THE SOUTHERN PLAINS AND LOWER MISSISSIPPI
VALLEY. SEVERAL ROUNDS OF SHOWERS AND THUNDERSTORMS ASSOCIATED
WITH PULSES UP INCREASED VORTICITY EJECTING OUT OF THE BASE OF THE
PARENT UPPER LEVEL LOW WILL IMPACT THE REGION THROUGH THIS
PERIOD...WITH THE RISK OF HEAVY RAINFALL AND LOCALLY SEVERE
THUNDERSTORMS EACH DAY. HOWEVER... THE RISK OF SEVERE
THUNDERSTORM DEVELOPMENT WILL BE GREATEST ON FRIDAY AND SATURDAY
AS OVERALL LAPSE RATES AND SHEAR PROFILES LOOK MORE FAVORABLE ON
THESE DAYS. THERE WILL BE A THREAT OF HEAVY RAINFALL THREAT EVERY
DAY AS PW VALUES REMAIN ELEVATED AT AROUND 1.75 INCHES AND THE
ATMOSPHERE REMAINS MOISTURE LOADED. GIVEN THIS THREAT...THE FLASH
FLOOD WATCH REMAINS IN EFFECT THROUGH FRIDAY EVENING. THE WATCH
MAY NEED TO BE EXTENDED INTO SATURDAY LATER TODAY.
FOR TODAY...AFTER REVIEWING THE GFSBUFR SOUNDINGS AND LOOKING AT
THE LATEST HRRR OUTPUT...EXPECT TO SEE CONVECTION INITIALLY IMPACT
AREAS AROUND BATON ROUGE THIS MORNING AND THEN SPREAD SOUTH AND
EAST INTO NEW ORLEANS AND THE MISSISSIPPI GULF COAST DURING THE
AFTERNOON AND EVENING HOURS. SOUNDING PROFILES ARE NOT AS
SUPPORTIVE OF SEVERE THUNDERSTORMS TODAY...AS MID-LEVEL LAPSE
RATES ARE CLOSER TO MOIST ADIABATIC AND THE WET BULB ZERO HEIGHT
REMAINS AROUND 13K FEET. ADDITIONALLY...THERE IS VERY LITTLE WIND SHEAR
NOTED OVER THE AREA. SPC HAS ONLY A MARGINAL RISK OF SEVERE
THUNDERSTORM DEVELOPMENT TODAY GIVEN THESE WEAKER PARAMETERS.
THE SOUNDING IS SUPPORTIVE OF LOCALLY HEAVY RAINFALL DEVELOPING
TODAY. THERE IS LITTLE IN THE WAY OF CONVECTIVE INHIBITION...SO IT
WILL NOT TAKE MUCH TO GET THUNDERSTORMS GOING. THESE THUNDERSTORMS
WILL HAVE A VERY EFFICIENT RAIN PROCESS...WHICH WILL ALLOW FOR
RAINFALL RATES OF UP TO 2 INCHES PER HOUR AT TIMES. THUS...SOME
LOCALIZED FLOODING WILL BE THREAT TODAY.
HEADING INTO TONIGHT...MUCH AS SEEN THE LAST FEW NIGHTS...THE
THUNDERSTORM ACTIVITY WILL QUICKLY DIMINISH AS DAYTIME HEATING
GIVES WAY. THERE WILL BE A RISK OF SOME SCATTERED SHOWERS AND B
THUNDERSTORMS DEVELOPING DURING THE NIGHT...BUT OVERALL COVERAGE
WILL BE MUCH LOWER THAN DURING THE PEAK HEATING HOURS.
TEMPERATURES WILL ONCE AGAIN COOL BACK INTO THE MIDDLE TO UPPER
60S...AND SOME PATCHY FOG WILL DEVELOP TOWARD DAYBREAK DUE TO THE
WET GROUND CONDITIONS AND A WEAK LOW LEVEL INVERSION CUTTING OFF
THE BOUNDARY LAYER WINDS. FOG COVERAGE LOOKS TO BE LOW ENOUGH TO
KEEP OUT OF THE OFFICIAL FORECAST FOR NOW.
FRIDAY LOOKS TO BE A VERY ACTIVE DAY ACROSS THE REGION. GFSBUFR
SOUNDINGS SHOW A MUCH MORE FAVORABLE ENVIRONMENT FOR SEVERE
THUNDERSTORM DEVELOPMENT...ESPECIALLY FROM LATE MORNING ON. MID-
LEVEL LAPSE RATES WILL INCREASE DRAMATICALLY FRIDAY
AFTERNOON...SHOOTING UP TO 7 C/KM BETWEEN 700 AND 500 MB. THESE
HIGH LAPSE RATES WILL ALSO BE ABOVE THE FREEZING LEVEL WHICH WILL
FALL BELOW 13K FEET. ADDITIONALLY...WET BULB ZERO HEIGHTS WILL
DROP TO AROUND 11K FEET. WITH STRONG LAPSE RATES IN THE HAIL
GROWTH ZONE...SOME LARGE HAIL WILL ONCE AGAIN BE POSSIBLE ON
FRIDAY. LOOKING AT THE WIND PROFILE...OVERALL HELICITY VALUES WILL
BE FAIRLY WEAK ON FRIDAY...BUT WITH SOME DRY AIR ADVECTING INTO
THE MID-LEVELS...THE THREAT OF STRAIGHT LINE WINDS AND BOWING
SEGMENTS INCREASES. THERE IS ENOUGH LOW LEVEL HELICITY...THAT AN
ISOLATED TORNADO COULD NOT BE RULED OUT FRIDAY AFTERNOON.
OVERALL...EXPECT THE MAIN THREAT TO BE HAIL AND STRAIGHT LINE
WINDS ON FRIDAY. CONDITIONS WILL ONCE AGAIN IMPROVE DURING THE
EVENING HOURS ON FRIDAY AS THE VORT MAX SLIDES TO THE EAST AND THE
ATMOSPHERE STABILIZES A BIT.
HOWEVER...THE PARENT UPPER LEVEL TROUGH WILL BEGIN TO DIRECTLY
IMPACT THE REGION ON SATURDAY AS IT MOVES THROUGH THE SOUTHERN
PLAINS. SATURDAY LOOKS TO HAVE THE HIGHEST THREAT OF BOTH HEAVY
RAINFALL AND SEVERE THUNDERSTORMS. PW VALUES WILL BE VERY
HIGH...APPROACHING 2 INCHES...AND THE OVERALL LAPSE RATES WILL
TURN MORE MOIST ADIABATIC THROUGH THE DAY. THIS WILL DECREASE THE
HAIL THREAT SUBSTANTIALLY...WITH WET BULB ZERO HEIGHTS REMAINING
WELL ABOVE 13K FEET. HOWEVER...VERY EFFICIENT RAINFALL PROCESSES
WILL DEVELOP...RESULTING IN HOURLY RAINFALL RATE POTENTIAL OF 2 TO
3 INCHES IF A STORM STALLS OVER THE SAME AREA. FORTUNATELY...THE
STORMS WILL BE FAST MOVING...SO ACTUAL RAINFALL RATES WILL BE
LOWER. THESE STRONG WINDS WILL UNFORTUNATELY MEAN THAT THE RISK OF
STRAIGHT LINE WINDS AND TORNADOES WILL BE HIGH ON SATURDAY. 0-3KM
SHEAR WILL INCREASE TO AROUND 35 KNOTS AND STORM RELATIVE HELICITY
VALUES WILL RISE TO AROUND 250 M2/S2 SATURDAY AFTERNOON. THESE
VALUES ARE VERY CONDUCIVE TO ROTATING THUNDERSTORM
DEVELOPMENT...AND THUS THE FORMATION OF TORNADOES. A FRONTAL
BOUNDARY WILL PUSH THROUGH THE AREA SATURDAY NIGHT...WHICH WILL
KEEP THE RISK OF SHOWERS AND THUNDERSTORMS IN PLACE THROUGH THE
NIGHT...AND HAVE LIKELY POPS IN PLACE TO REFLECT THIS.
.LONG TERM...
CONDITIONS WILL BEGIN TO IMPROVE ON SUNDAY...AS A COLD FRONT
PUSHES OFFSHORE AND RAIN CHANCES SHOULD DECREASE THROUGH THE DAY
FROM WEST TO EAST. THE PARENT UPPER LEVEL TROUGH AXIS WILL FINALLY
PUSH THROUGH THE REGION SUNDAY NIGHT...WITH INCREASING NEGATIVE
VORTICITY ADVECTION AND SUBSIDENCE TAKING HOLD OF THE AREA FOR
MONDAY. AT MOST...THERE COULD BE SOME LINGERING SHOWERS AND CLOUDS
ALONG THE IMMEDIATE COAST MONDAY MORNING...WITH CLEARING
CONDITIONS EXPECTED BY MONDAY AFTERNOON. AS A MORE ZONAL FLOW
REGIME TAKES HOLD ALOFT...AND SOME DRIER MID-LEVEL AIR LINGERS
OVER THE AREA SKIES SHOULD REMAIN PARTLY CLOUDY AND RAIN CHANCES
WILL BE LESS THAN 10 PERCENT FOR TUESDAY. TEMPERATURES WILL REMAIN
NEAR NORMAL...WITH HIGHS IN THE LOWER 80S AND LOWS IN THE UPPER
50S AND LOWER 60S.
UNFORTUNATELY...A WEAK IMPULSE RIDING ALONG THE ZONAL FLOW WILL
SLIDE THROUGH THE AREA ON WEDNESDAY. THE SYSTEM WILL BE FAIRLY
WEAK...BUT ENOUGH FORCING AND MOISTURE WILL BE IN PLACE TO SPARK
OFF SOME SCATTERED SHOWERS AND THUNDERSTORMS DURING THE DAY ON
WEDNESDAY. RAIN CHANCES WILL BE HIGHEST ALONG THE COAST AND
OFFSHORE WHERE OVERALL MOISTURE AND FORCING IS EXPECTED TO BE
GREATEST. AS THIS FEATURE PULLS TO THE EAST WEDNESDAY...SKIES
SHOULD CLEAR AND RAIN CHANCES WILL DROP. HOWEVER...ANOTHER IMPULSE
WILL SLIDE THROUGH ON THURSDAY...BRINGING ANOTHER CHANCE OF
ISOLATED SHOWERS AND THUNDERSTORMS FOR THURSDAY.
&&
.AVIATION...
TAFS WILL BE DEPENDENT ONCE AGAIN ON EVENTUAL CONVECTIVE DEVELOPMENTS TODAY.
CONVECTIVE BASED MODELS SUGGEST ONSET OF STORMS COULD IMPACT SOME LOCATIONS
BY 14Z...PRIMARILY WESTERNMOST LOCATIONS LIKE KBTR AND KHUM...THOUGH ALL
TERMINALS SHOULD SEE SOME PERIODS OF TSRA/SHRA THROUGHOUT THE DAY. DOWN BURST
POTENTIAL WILL BE HIGH TODAY WITH GUST POTENTIAL 35-45 KT. EFFICIENT RAINFALL
PROCESS SHOULD ALSO LOWER VSBY TO VLIFR LEVELS AT TIMES DURING HEAVY RAINFALL.
OTHERWISE...VFR CONDITIONS SHOULD PREVAIL AFTER 16Z OUTSIDE
CONVECTION.
&&
.MARINE...
AN INTERESTING WAKE LOW PHENOMENA IMPACTED THE OFFSHORE WATERS
THIS MORNING...BUT THIS HAS SINCE WEAKENED. OVERALL...EXPECT TO
SEE AN ONSHORE FLOW OF 10 TO 15 KNOTS REMAIN OVER THE COASTAL
WATERS THROUGH FRIDAY. AS AN UPPER LEVEL LOW AND ASSOCIATED WEAK
SURFACE LOW AND FRONT MOVE THROUGH OVER THE WEEKEND...WINDS WILL
INCREASE INTO EXERCISE CAUTION RANGE SATURDAY AND REMAIN ELEVATED
INTO SUNDAY. SEAS WILL RESPOND AND INCREASE TO 3 TO 5 FEET IN THE
OFFSHORE WATERS. THE GRADIENT WILL EASE OVER THE AREA ON
MONDAY...ALLOWING FOR WEAKER AND MORE VARIABLE FLOW OF 10 KNOTS OR
LESS. SEAS WILL ALSO FALL BACK INTO THE 1 TO 3 FEET RANGE FOR
MONDAY AND TUESDAY.
&&
.DECISION SUPPORT...
DSS CODE...BLUE.
DEPLOYED...NONE.
ACTIVATION...NONE.
ACTIVITIES...MONITORING HEAVY RAINFALL/FLOODING POTENTIAL
ASSESSING SEVERE WEATHER THREAT THRU WEEKEND.
DECISION SUPPORT SERVICES (DSS) CODE LEGEND
GREEN = NO WEATHER IMPACTS THAT REQUIRE ACTION
BLUE = LONG FUSED WATCH/WARNING/ADVISORY IN EFFECT OR HIGH
VISIBILITY EVENT
YELLOW = HEIGHTENED IMPACTS WITH SHORT FUSED
WATCH/WARNING/ADVISORY ISSUANCES; RADAR SUPPORT
ORANGE = HIGH IMPACTS - SLIGHT TO MODERATE RISK SEVERE; NEARBY
TROPICAL EVENTS; HAZMAT OR OTHER LARGE EPISODES
RED = FULL ENGAGEMENT FOR MODERATE TONIGHT RISK SVR
AND/OR DIRECT TROPICAL THREATS; EVENTS OF NATIONAL
SIGNIFICANCE
&&
.PRELIMINARY POINT TEMPS/POPS...
MCB 78 65 79 66 / 80 60 70 50
BTR 79 66 81 67 / 80 60 70 50
ASD 78 67 80 68 / 70 70 70 60
MSY 78 69 80 69 / 70 70 70 60
GPT 77 68 78 69 / 70 70 70 70
PQL 78 67 79 69 / 70 70 70 70
&&
.LIX WATCHES/WARNINGS/ADVISORIES...
LA...FLASH FLOOD WATCH THROUGH FRIDAY EVENING FOR LAZ040-046>050-
056>070-072.
GM...NONE.
MS...FLASH FLOOD WATCH THROUGH FRIDAY EVENING FOR MSZ077-080>082.
GM...NONE.
&&
$$
32
AREA FORECAST DISCUSSION
NWS PITTSBURGH PA
405 AM EDT THU APR 16 2015
.SYNOPSIS...
A WEAK UPPER LEVEL DISTURBANCE AND TRAILING COLD FRONT WILL BRING
SHOWERS TODAY THROUGH FRIDAY MORNING. A DRY AND COMFORTABLE START
TO THE WEEKEND.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
SHOWER CHANCES WILL INCREASE FROM WEST TO EAST THIS MORNING AHEAD
OF A SHORTWAVE TROUGH THAT REACHES THE AREA LATE THIS AFTERNOON.
STILL SEEING SOME TIMING DIFFERENCES IN MODEL SOLUTIONS AS THE
MOISTURE ASSOCIATED WITH THE UPPER LEVEL WAVE WILL BE RUNNING INTO
A VERY DRY ATMOSPHERE. THINK A SLOWER APPROACH TO BEGINNING THE
SHOWERS IS THE WAY TO GO. SHOWERS WILL OVERSPREAD THE ENTIRE AREA
THIS AFTERNOON AS THE WAVE MOVES THROUGH.
WITH THE CLOUDS AND SHOWERS...TEMPERATURES WILL BE A BIT BELOW
SEASONABLE LEVELS.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH SATURDAY/...
SHOWERS CONTINUE OVERNIGHT AND INTO FRIDAY MORNING AS THE SURFACE
BOUNDARY SLOWLY MOVES THROUGH THE REGION. UPPER LEVEL SUPPORT
WILL QUICKLY EXIT THE AREA...SO EXPECT THE SHOWERS TO RAP UP IN
THE EAST FRIDAY MORNING. NO REAL DISCERNIBLE COLD ADVECTION IS
EXPECTED...SO TEMPERATURES WILL BE ABLE TO REBOUND BACK TO...IF
NOT WARMER THAN SEASONAL AVERAGES FRIDAY AFTERNOON.
BROAD SURFACE HIGH AND UPPER LEVEL RIDGE WILL BUILD INTO THE OHIO
VALLEY SATURDAY.
&&
.LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/...
MODELS STILL SHOWING A LARGE AND SLOW MOVING SYSTEM THAT WILL
BRING AN EXTENDED PERIOD OF SHOWERS BEGINNING SUNDAY AND
CONTINUING INTO EARLY TUESDAY. DRY AND SEASONABLE WEATHER WILL
RETURN BEHIND THIS SYSTEM.
&&
.AVIATION /08Z THURSDAY THROUGH MONDAY/...
VFR CONDITIONS WILL CONTINUE OVERNIGHT. TERMINALS MAY SEE MVFR CIG
RESTRICTIONS BY TOMORROW EVENING WITH SCATTERED SHOWERS ACROSS
THE REGION.
.OUTLOOK.../TUESDAY NIGHT THROUGH SUNDAY/...
THE NEXT CHANCE FOR GENERAL RESTRICTIONS IS EXPECTED WITH THE
APPROACH OF LOW PRESSURE ON SUNDAY.
&&
.PBZ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
OH...NONE.
PA...NONE.
WV...NONE.
&&
$$
AREA FORECAST DISCUSSION...UPDATED
NWS PITTSBURGH PA
105 AM EDT THU APR 16 2015
.SYNOPSIS...
A WEAK UPPER LEVEL DISTURBANCE AND TRAILING COLD FRONT WILL BRING
SHOWERS TODAY THROUGH FRIDAY MORNING. A DRY AND COMFORTABLE START
TO THE WEEKEND.
&&
.NEAR TERM /THROUGH TODAY/...
OVERNIGHT PERIOD IN GOOD SHAPE. JUST MADE MINOR ADJUSTMENTS TO THE
ONSET OF POPS AS DAWN APPROACHES. TEMPERATURES HAVE BEEN NUDGED
TOWARD THE LATEST LAMP NUMBERS.
SHOWER CHANCES WILL INCREASE FROM WEST TO EAST THIS MORNING AHEAD
OF A SHORTWAVE TROUGH THAT REACHES THE AREA LATE THIS AFTERNOON.
STILL SEEING SOME TIMING DIFFERENCES IN MODEL SOLUTIONS AS THE
MOISTURE ASSOCIATED WITH THE UPPER LEVEL WAVE WILL BE RUNNING INTO
A VERY DRY ATMOSPHERE. THINK A SLOWER APPROACH TO BEGINNING
SHOWERS IS THE WAY TO GO. SHOWERS WILL OVERSPREAD THE ENTIRE AREA
THIS AFTERNOON AS THE WAVE MOVES THROUGH.
WITH THE CLOUDS AND SHOWERS...TEMPERATURES WILL BE A BIT BELOW
SEASONABLE LEVELS.
&&
.SHORT TERM /TONIGHT THROUGH SATURDAY/...
SHOWERS CONTINUE OVERNIGHT AND INTO FRIDAY MORNING AS THE SURFACE
BOUNDARY SLOWLY MOVES THROUGH THE REGION. UPPER LEVEL SUPPORT
WILL QUICKLY EXIT THE AREA...SO EXPECT THE SHOWERS TO RAP UP IN
THE EAST FRIDAY MORNING. NO REAL DISCERNIBLE COLD ADVECTION IS
EXPECTED...SO TEMPERATURES WILL BE ABLE TO REBOUND BACK TO...IF
NOT WARMER THAN SEASONAL AVERAGES FRIDAY AFTERNOON.
BROAD SURFACE HIGH AND UPPER LEVEL RIDGE WILL BUILD INTO THE OHIO
VALLEY SATURDAY.
&&
.LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/...
MODELS STILL SHOWING A LARGE AND SLOW MOVING SYSTEM THAT WILL
BRING AN EXTENDED PERIOD OF SHOWERS BEGINNING SUNDAY AND
CONTINUING INTO EARLY TUESDAY. DRY AND SEASONABLE WEATHER WILL
RETURN BEHIND THIS SYSTEM.
&&
.AVIATION /05Z THURSDAY THROUGH MONDAY/...
VFR CONDITIONS WILL CONTINUE OVERNIGHT. TERMINALS MAY SEE MVFR CIG
RESTRICTIONS BY TOMORROW EVENING WITH SCATTERED SHOWERS ACROSS
THE REGION.
.OUTLOOK.../TUESDAY NIGHT THROUGH SUNDAY/...
THE NEXT CHANCE FOR GENERAL RESTRICTIONS IS EXPECTED WITH THE
APPROACH OF LOW PRESSURE ON SUNDAY.
&&
.PBZ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
OH...NONE.
PA...NONE.
WV...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS DULUTH MN
345 AM CDT THU APR 16 2015
.SHORT TERM...(TODAY THROUGH FRIDAY)
ISSUED AT 343 AM CDT THU APR 16 2015
CURRENT RADAR IMAGERY SHOWS SCATTERED ECHOS LIFTING NORTH OVER MUCH
OF MN EARLY THIS MORNING IN A REGION OF MID LEVEL WARM AIR ADVECTION
AHEAD OF AN APPROACHING COLD FRONT. HOWEVER...THE VERY DRY AIR IN
PLACE IS LIMITING MORE THAN A FEW SPRINKLES FROM REACHING THE GROUND
WITH CEILINGS REMAINING ABOVE 6 KFT. THE MORNING CONVECTION WILL
DISSIPATE AFTER SUNRISE...REDEVELOPING ALONG THE FRONTAL BOUNDARY
THIS AFTERNOON IN THE BORDERLAND/ARROWHEAD REGION. ANY SHOWERS THAT
DEVELOP LATE TODAY WILL AGAIN HAVE TO CONTENT WITH VERY DRY LOW
LEVELS...RESULTING IN PRIMARILY VIRGA AND LIMITING ANY QPF TO ONLY A
FEW HUNDREDTHS AT BEST. LOCATIONS THAT DO RECEIVE A PASSING
SPRINKLE/VIRGA CAN EXPECT A LOCALIZED WIND GUST TO 25 MPH THIS
AFTERNOON...MAINLY IN THE MN ARROWHEAD. THE FRONT WILL REACH THE
WISCONSIN ZONES THIS EVENING...BRINGING INCREASING CLOUDS AND
LIGHT AND VARIABLE WINDS. THE CLOUD COVER TODAY WILL ALLOW FOR
SOMEWHAT COOLER TEMPERATURES THAN THE PAST FEW DAYS...TOPPING OUT
IN THE LOW TO MIDDLE 60S TODAY. HOWEVER...THIS IS STILL 10 TO 15
DEGREES ABOVE NORMAL FOR MID APRIL.
TEMPERATURES CLOSER TO 70 WILL RETURN WITH SUNNY SKIES FRIDAY AS
RIDGE OF HIGH PRESSURE BUILDS ACROSS THE NORTHLAND. A CORRIDOR
OF VERY DRY AIR WITH RH VALUES IN TEENS TO LOW 20S IS EXPECTED TO
SETTLE OVER THE NE MINN AND FAR NRN WISCONSIN THROUGH FRIDAY
EVENING. WINDS WILL BE OUT OF THE WEST AROUND 5 TO 10 MPH OVER MOST
AREAS FRIDAY...EXCEPT STRONGER WITH GUSTS TO 25 MPH ALONG THE
INTERNATIONAL BORDER AS A COLD FRONT IN ONTARIO APPROACHES THE
BORDERLAND.
.LONG TERM...(FRIDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 343 AM CDT THU APR 16 2015
FRIDAY NIGHT...A SUBTLE COLD FRONT WILL MOVE INTO THE NORTHLAND IN
THE WAKE OF A WEAK LOW MOVING THROUGH ONTARIO INTO QUEBEC. HIGH
PRESSURE WILL BUILD INTO ONTARIO AND THE LAKE SUPERIOR REGION IN
THE WAKE OF THE FRONT. THE NORTHLAND CAN EXPECT A CLEAR AND COOL
NIGHT WITH LIGHT WINDS.
SATURDAY...THE DAY WILL BEGIN COOL AND CLEAR. EASTERLY WINDS WILL
DEVELOP AS THE HIGH PRESSURE SHIFTS EAST TOWARDS QUEBEC AND THE
EASTERN GREAT LAKES AND IN RESPONSE TO LOW PRESSURE BUILDING INTO
THE AMERICAN AND CANADIAN PLAINS. THERE WILL BE A CUTOFF LOW OVER
THE HIGH PLAINS OF COLORADO...AND A DEEPENING LOW IN CENTRAL
SASKATCHEWAN MOVING TO THE SE. THERE WILL BE INCREASING CLOUD COVER
OVER THE NORTHLAND SATURDAY AS THE MOISTURE FROM THE CUTOFF LOW
BEGINS TO MOVE INTO THE NORTHLAND FROM THE SOUTH. THE EAST TO NE
FLOW OFF OF LAKE SUPERIOR WILL KEEP AREAS NEAR LAKE SUPERIOR COOL IN
THE UPPER 40S AND 50S...BUT AREAS OF THE NORTHLAND WELL INLAND
SHOULD CLIMB TO THE LOWER 60S.
SATURDAY NIGHT AND SUNDAY...THE LOW IN SASKATCHEWAN WILL DEEPEN AS
IT MOVES SE INTO MANITOBA. THE CUTOFF LOW NEAR THE COLORADO/NEBRASKA
BORDER WILL MOVE ENE TOWARDS THE UPPER MIDWEST. SURFACE LOW PRESSURE
WILL DEVELOP IN THE DAKOTAS SATURDAY NIGHT AND MOVE INTO THE
NORTHLAND AND MERGE WITH THE LOW IN SOUTH CENTRAL CANADA. THE LOW
PRESSURE WILL BRING A SURGE OF HUMID AIR AND RAIN INTO THE NORTHLAND
SATURDAY NIGHT AND SUNDAY. THE MODELS ARE IN BETTER AGREEMENT ON THE
TIMING OF THIS PCPN COMPARED TO PREVIOUS RUNS...ESPECIALLY BETWEEN
THE GFS AND ECMWF. THEREFORE...WAS ABLE TO INCREASE PCPN CHANCES BY
ABOUT 10 TO 20 PERCENT. THE PRECIPITABLE WATER VALUES WILL INCREASE
TO AROUND 1 INCH. THE NORTHLAND WILL LIKELY GET AT LEAST WIDESPREAD
RAINFALL OF 0.50" TO 0.75" OF RAINFALL WITH THE PASSAGE OF THIS LOW
PRESSURE.
EARLY NEXT WEEK...THE LOW PRESSURE SYSTEMS WILL MERGE AND DEEPEN
INTO A LARGE LOW PRESSURE SYSTEM OVER THE GREAT LAKES AND ONTARIO
REGION. THE NORTHLAND CAN EXPECT A PERIOD OF COOLER AND CLOUDIER
WEATHER FOR THE MONDAY THROUGH WEDNESDAY TIMEFRAME WITH CHANCES OF
RAIN AND LIGHT SNOW SHOWERS. TEMPERATURES WILL BE ABOUT 10 DEGREES
BELOW NORMAL.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z THURSDAY NIGHT)
ISSUED AT 104 AM CDT THU APR 16 2015
VFR CONDITIONS EXPECTED THROUGHOUT THE FORECAST. INCREASING AMOUNT
OF MOISTURE MOVING INTO THE NORTHLAND AS HIGH PRESSURE DEPARTS TO
THE EAST...AND AN UPPER LEVEL DISTURBANCE MOVES THROUGH MINNESOTA.
LAST SEVERAL HRRR RUNS SHOW THE BEST CHANCE OF -RA AT KBRD. OTHER
MN TERMINALS MAY SEE VCSH BETWEEN 14Z AND 20Z THIS MORNING...BUT
NOT VERY CONFIDENT THAT MUCH IF ANY WILL REACH THE GROUND AS
LATEST GFS AND NAM SOUNDINGS KEEP THE LOW LEVELS FAIRLY DRY.
&&
.PRELIMINARY POINT TEMPS/POPS...
DLH 62 37 67 39 / 10 10 0 0
INL 62 31 67 33 / 20 10 10 0
BRD 67 36 70 41 / 20 10 0 0
HYR 65 37 70 38 / 10 10 0 0
ASX 67 37 69 37 / 10 10 0 0
&&
.DLH WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...NONE.
LS...NONE.
&&
$$
SHORT TERM...GRANING
LONG TERM...GROCHOCINSKI
AVIATION...GROCHOCINSKI/WL
AREA FORECAST DISCUSSION
NWS DULUTH MN
105 AM CDT THU APR 16 2015
.SHORT TERM...(THIS EVENING THROUGH THURSDAY AFTERNOON)
ISSUED AT 326 PM CDT WED APR 15 2015
MAIN CONCERNS IN THE SHORT TERM REMAIN FOCUSED AROUND THE GUSTY
SOUTH WINDS AND VERY DRY CONDITIONS ACROSS THE REGION THIS
EVENING...THE POTENTIAL FOR LIGHT RAIN SHOWERS OVERNIGHT TONIGHT
AND THROUGH THE DAY THURSDAY ACROSS NE MN.
HIGH PRESSURE AT THE SURFACE REMAINS SITUATED OVER THE NRN GREAT
LAKES WITH AN ELONGATED SFC TROUGH EXTENDING FROM NRN MANITOBA SWD
INTO THE WRN DAKOTAS. THE COMBINATION OF THESE TWO FEATURES IS
PRODUCING A TIGHT SFC PRESSURE GRADIENT OVER THE ERN DAKOTAS AND
MOST OF MINNESOTA. GUSTY SOUTH WINDS HAVE DEVELOPED OVER THE
REGION WITH SUSTAINED WINDS AROUND 10 TO 20 MPH AND GUSTS UP TO 35
MPH HAVE BEEN OBSERVED THIS AFTERNOON.
AN EMBEDDED S/W IS CURRENTLY LIFTING TO THE NORTH THROUGH THE MID
MS VALLEY REGION THIS AFTERNOON AND TRYING TO UNDERCUT THE SFC
HIGH WITH CLOUD COVER AND LIGHT RAIN. HOWEVER...FOR THE TIME THE
DRY AIR MASS IS WINNING OUT AND KEEPING MUCH OF THE AREA FREE OF
PRECIPITATION.
THE INFLUENCE FROM THE RIDGE TO THE EAST WILL EVENTUALLY MOVE TO
THE EAST TONIGHT AS THE UPPER TROUGH LIFTS INTO MN. THIS WILL
ALLOW FOR A STRONGER PUSH OF CLOUD COVER FROM THE SOUTH ALONG WITH
LOW CHANCES FOR LIGHT RAIN SHOWERS...MAINLY OVER N-CENTRAL MN JUST
AFTER MIDNIGHT AND THEN EVENTUALLY SHIFTING TO THE EAST INTO THE
ARROWHEAD THROUGH THE DAY THURSDAY AS THE SFC TROUGH/COLD FRONT IS
DRAGGED SLOWLY TO THE EAST. ONLY EXPECTING LIGHT AMOUNTS LESS
THAN A TENTH OF AN INCH WITH THIS RAIN EVENT. HIGH PRESSURE WILL
BUILD IN BRIEFLY BEHIND THE DEPARTING COLD FRONT LATE THUR
AFTERNOON.
.LONG TERM...(THURSDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 326 PM CDT WED APR 15 2015
SFC RIDGING COVERS THE FORECAST AREA THURSDAY NIGHT THROUGH
SATURDAY. THE GFS IS WAY OVERDONE WITH ITS HANDLING OF A SYSTEM ON
SATURDAY AND WAS IGNORED. SATURDAY NIGHT FINDS RAIN ARRIVING OVER
MUCH OF THE AREA AS A CLOSED UPPER LOW DEVELOPS OVER THE MANITOBA
LAKES. AS THIS UPPER LOW DEEPENS WHILE MOVING SLOWLY EASTWARD...IT
MERGES WITH A SOUTHERN STREAM SYSTEM ON SUNDAY. THIS PULLS MORE
MOISTURE INTO THE AREA FOR THIS PHASING SYSTEM TO FEED OFF OF. ON
SUNDAY NIGHT...THE UPPER LOW CONTINUES TO DEEPEN AND BEGINS TO PULL
DOWN COLDER AIR FROM THE ARCTIC...MUCH LIKE A WINTER SYSTEM.
HOWEVER...AT THIS TIME OF THE YEAR IT IS BECOMING MORE DIFFICULT TO
HAVE A TRUE SNOW EVENT. THIS SYSTEM THEN BECOMES LOCKED IN PLACE
JUST NORTH OF LAKE SUPERIOR THROUGH TUESDAY. WILL SEE RAIN DURING
THE DAY AND A RAIN/SNOW MIX IN THE EVENING...WITH JUST A FEW SHORT
HOURS OF ALL SNOW POSSIBLE LATE EACH NIGHT. NO SNOW ACCUMULATION IS
EXPECTED. MAX AND MIN TEMPS WILL BECOME BELOW NORMAL SATURDAY NIGHT
THROUGH TUESDAY.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z THURSDAY NIGHT)
ISSUED AT 104 AM CDT THU APR 16 2015
VFR CONDITIONS EXPECTED THROUGHOUT THE FORECAST. INCREASING AMOUNT
OF MOISTURE MOVING INTO THE NORTHLAND AS HIGH PRESSURE DEPARTS TO
THE EAST...AND AN UPPER LEVEL DISTURBANCE MOVES THROUGH MINNESOTA.
LAST SEVERAL HRRR RUNS SHOW THE BEST CHANCE OF -RA AT KBRD. OTHER
MN TERMINALS MAY SEE VCSH BETWEEN 14Z AND 20Z THIS MORNING...BUT
NOT VERY CONFIDENT THAT MUCH IF ANY WILL REACH THE GROUND AS
LATEST GFS AND NAM SOUNDINGS KEEP THE LOW LEVELS FAIRLY DRY.
&&
.PRELIMINARY POINT TEMPS/POPS...
DLH 38 65 37 57 / 10 0 0 10
INL 33 64 33 61 / 0 10 0 10
BRD 36 67 35 63 / 10 0 0 10
HYR 37 67 38 63 / 10 0 0 10
ASX 37 67 37 58 / 10 0 0 10
&&
.DLH WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...NONE.
LS...NONE.
&&
$$
SHORT TERM...BJT
LONG TERM...GSF
AVIATION...GROCHOCINSKI/WL
AREA FORECAST DISCUSSION
NWS HASTINGS NE
415 AM CDT THU APR 16 2015
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 412 AM CDT THU APR 16 2015
RADAR SHOWS SHOWERS AND THUNDERSTORMS MOVING NORTH/NORTHEAST WITH
DEVELOPMENT ON THE SOUTH END OF THE MAIN CLUSTER OF THUNDERSTORMS.
SURFACE ANALYSIS SHOWS A LOW PRESSURE SYSTEM ACROSS WESTERN KANSAS
WITH A COLD FRONT EXTENDING TO THE NORTH ACROSS NEBRASKA.
AN UPPER LEVEL LOW IN THE IN THE FOUR CORNERS REGION WILL DRIFT
TOWARD THE EAST TODAY AND TONIGHT. IN ADVANCE OF THE UPPER LOW A FEW
WAVES WILL MOVE ACROSS THE AREA THROUGH TONIGHT. THE NAM AND GFS
BOTH SPREAD THE PRECIPITATION ACROSS THE FORECAST AREA THROUGH THE
MORNING HOURS AS THE FIRST OF THE WAVES MOVE THROUGH THE FORECAST
AREA. THE RAP AND THE 4KM WRF BOTH INDICATE THIS INITIAL GROUP OF
THUNDERSTORMS WILL MOVE THROUGH AND ALTHOUGH THERE MAY BE SOME
ISOLATED THUNDERSTORMS AROUND...THERE COULD BE A BREAK THIS MORNING.
HAVE KEPT POPS ACROSS THE AREA...BUT DID LOWER THEM A BIT THIS
MORNING.
THE NEXT WAVE WILL MOVE INTO THE AREA THIS AFTERNOON AND EVENING.
THUNDERSTORMS SHOULD DEVELOP IN WESTERN KANSAS AND SPREAD INTO THE
AREA DURING THE AFTERNOON. LATE AFTERNOON INTO THE EARLY EVENING THE
MUCAPE INCREASES TO NEARLY 2500 J/KG MAINLY ACROSS KANSAS. THIS IS
THE AREA WITH THE BEST CHANCE FOR SOME SEVERE WEATHER. ANOTHER UPPER
LEVEL WAVE PUSHES INTO THE AREA LATE TONIGHT. SHOWERS AND
THUNDERSTORMS ARE EXPECTED ACROSS THE AREA LATE TONIGHT.
.LONG TERM...(FRIDAY THROUGH WEDNESDAY)
ISSUED AT 412 AM CDT THU APR 16 2015
A PAIR OF UPPER LEVEL LOWS FORECAST TO TRACK ACROSS THE SOUTHERN
HALF OF THE COUNTRY WILL BRING SOME SIGNIFICANT CHANCES FOR
BENEFICIAL RAINFALL TO THE REGION OVER THE NEXT WEEK OR SO. THE
FIRST OF THESE LOW PRESSURE SYSTEMS IS CURRENTLY SPINNING ACROSS THE
DESERT SOUTHWEST...AND ALREADY HAVING AN IMPACT ON THE LOCAL
WEATHER. WITH THIS LOW CUT OFF FROM THE MAIN UPPER LEVEL FLOW ACROSS
CANADA...EXPECT VERY SLOW PROGRESSION TOWARDS THE EAST TO RESULT IN
MULTIPLE DAYS OF UNSETTLED WEATHER ACROSS THE REGION.
WITH MOIST SOUTHERLY FLOW AHEAD OF THIS SYSTEM...DEWPOINTS HAVE
SURGED INTO THE 50S ACROSS MUCH OF THE LOCAL AREA AND EXPECT THE
ASSOCIATED INSTABILITY TO HELP AID IN THE FORMATION OF THUNDERSTORMS
BOTH FRIDAY AND SATURDAY. THAT SAID...WITH MUCH BETTER SHEAR TO WORK
WITH ON FRIDAY AFTERNOON/EVENING...THIS APPEARS TO BE THE BEST SHOT
FOR MORE WIDESPREAD STRONG AND POTENTIALLY SEVERE STORMS ACROSS THE
REGION...AND NOT SURPRISINGLY ROUGHLY THE SOUTHERN HALF OF THE
FORECAST AREA IS NOW OUTLOOKED BY SPC. IF REALIZED...THE MAIN
HAZARDS ARE LIKELY TO BE LARGE HAIL AND STRONG WIND GUSTS.
WHILE STILL NOT OUT OF THE QUESTION FOR SATURDAY...ADDITIONAL STRONG
TO MARGINALLY SEVERE THUNDERSTORMS WILL BE POSSIBLE DURING THE
AFTERNOON AND EVENING HOURS...BUT DUE TO DIMINISHED SHEAR
VALUES...THINK THE COVERAGE OF THESE STRONGER STORMS WILL BE MUCH
MORE LIMITED. EVEN SO...WIDESPREAD BENEFICIAL RAINFALL IS
ANTICIPATED FOR THE ENTIRE REGION BOTH DAYS...WITH STORM TOTAL
PRECIPITATION AMOUNTS OVER 2 INCHES EXPECTED TO BE FAIRLY WIDESPREAD
BY THE TIME THE RAINFALL ENDS AND THE RESPONSIBLE LOW PRESSURE
SYSTEM TRACKS EASTWARDS SUNDAY AFTERNOON.
THIS LOW PRESSURE SYSTEM WILL BE SHIFTED EASTWARD BY A FAIRLY STRONG
COLD FRONT FORECAST TO DROP SOUTH ACROSS THE LOCAL AREA SUNDAY. THIS
COLD FRONT WILL BRING SIGNIFICANTLY COOLER TEMPERATURES TO START THE
NEW WORK WEEK WITH POTENTIALLY SOME NEAR FREEZING TEMPERATURES
CURRENTLY FORECAST FOR BOTH MONDAY AND TUESDAY MORNINGS. WHILE
ACTUAL FROST MAY NOT DEVELOP EITHER DAY...THESE COOLER TEMPERATURES
WILL BE SOMETHING TO MONITOR AS SENSITIVE VEGETATION MAY BE
IMPACTED. ADDITIONALLY...WITH STRONG NORTHWESTERLY WINDS BEHIND THIS
FRONT AND DRIER AIR ADVECTING IN FROM THE NORTH...COULD EVENTUALLY
SEE SOME NEAR CRITICAL FIRE WEATHER CONDITIONS REALIZED ACROSS
ROUGHLY THE NORTHWESTERN HALF OF THE LOCAL AREA. BECAUSE BOTH OF
THESE POTENTIAL HAZARDS ARE STILL SEVERAL DAYS OUT AND
MARGINAL...OPTED NOT TO MENTION EITHER OF THESE IN THE MORNING HWO.
THEREAFTER...RAINFALL CHANCES WILL INCREASE MIDWEEK AS ANOTHER UPPER
LEVEL LOW MOVES INTO THE DESERT SOUTHWEST AND MOISTURE INCREASES
ACROSS THE REGION.
&&
.AVIATION...(FOR THE 06Z KGRI/KEAR TAFS THROUGH 06Z THURSDAY NIGHT)
ISSUED AT 1225 AM CDT THU APR 16 2015
THUNDERSTORMS ARE GRADUALLY MOVING IN FROM THE WEST. THUNDERSTORMS
ARE EXPECTED ON AND OFF THROUGH MUCH OF THE DAY. THE SURFACE LOW
TO THE SOUTHWEST WILL KEEP WINDS FROM THE EAST OR SOUTHEAST
THROUGH THE PERIOD. THE LOWEST CEILINGS WILL BE BEFORE SUNRISE
THIS MORNING.
&&
.GID WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
KS...NONE.
&&
$$
SHORT TERM...JCB
LONG TERM...ROSSI
AVIATION...JCB
AREA FORECAST DISCUSSION
NWS OMAHA/VALLEY NE
1150 PM CDT WED APR 15 2015
.SHORT TERM...(TONIGHT)
ISSUED AT 309 PM CDT WED APR 15 2015
LARGE SCALE PATTERN PER WV IMAGERY THIS AFTN SHOWING FAST ZONAL FLOW
WITH SEVERAL EMBEDDED WAVES EXTENDING ACROSS SRN CANADA WITH A LARGE
CLOSED OFF CIRCULATION SITUATED OVER THE GREAT BASIN. AT THE
SFC...LLVL MOISTURE RETURN IS UNDERWAY WITH DEW POINTS INCREASING
OVER THE LOWER/MID MS VLY REGION. RUC13 SHOWING BNDRY LYR MOISTURE
ADV CONTINUING THRU TONIGHT WITH PW VALUES INCREASING TO AROUND AN
INCH OVER THE CWA. TSTM DEVELOPMENT PROGGED TO OCCUR OVER CNTRL KS/S-
CNTRL NEB LATER THIS EVENING WITHIN AREA OF ELEVATED
INSTABILITY/NOSE OF LLVL JET...THEN EXPAND NEWD INTO THE WRN CWA
SOMETIME AFT MIDNIGHT AS UPGLIDE INCREASES ALONG 300K SFC. PLAN ON
ONLY MAKING MINOR TWEAKS AT THIS POINT AS GOING FCST IS IN DECENT
SHAPE DEPICTING POPS INCREASING FROM WEST TO EAST DURING THE
OVERNIGHT HOURS.
.LONG TERM...(THURSDAY THROUGH WEDNESDAY)
ISSUED AT 309 PM CDT WED APR 15 2015
MAIN FORECAST CONCERN WILL BE PROGRESSION OF WESTERN CONUS UPPER LOW
AND ITS IMPACTS AS IT SLIDE ACROSS THE CENTRAL PLAINS.
BY THURSDAY MORNING...THE WESTERN CONUS UPPER LOW WILL BE CENTERED
ON TOP OF THE FOUR CORNERS REGION. LEE SIDE SFC LOW REFLECTION IS
FORECAST TO BE FAIRLY BROAD ACROSS THE TEXAS PANHANDLE WITH AN
INVERTED TROUGH EXTENDING NORTHEAST ACROSS WESTERN KS AND INTO
WESTERN NEBRASKA. PRECIPITATION WILL CONTINUE TO SPREAD EAST INTO
OUR WESTERN CWA...BECOMING LIKELY LATER IN THE DAY THURSDAY AS
BROAD SCALE ASCENT INCREASES WITH LEAD SHORTWAVE ENERGY. THE UPPER
LOW WILL SLOWLY MOVE INTO THE SOUTHERN PLAINS AND IS FORECAST TO
OPEN UP THROUGH THE WEEKEND PROVIDING CONTINUED BROAD SCALE
VERTICAL MOTION THROUGH SUNDAY. LOW LEVEL MOISTURE ALREADY IN
PLACE ACROSS THE SOUTHERN PLAINS WILL CONTINUE TO STREAM NORTHWARD
AS THE SFC LOW PRESSURE CENTER BETTER ORGANIZES ACROSS EASTERN
COLORADO BY FRIDAY MORNING. PW`S WILL REMAIN ABOVE 1" THROUGH THE
PERIOD. ALTHOUGH RAIN IS LIKELY AT TIMES THROUGH SUNDAY...WE WILL
HAVE A FEW INTERMITTENT BREAKS BUT TOO DIFFICULT TO DETERMINE AT
THIS POINT WITH SUCH SLOW PROGRESSION OF THE UPPER LOW. BEST
CHANCE FOR THUNDERSTORMS LOOKS TO BE THURSDAY AND FRIDAY
AFTERNOON...ESPECIALLY ACROSS THE SOUTHERN CWA. HAVE INCLUDED
ISOLATED THUNDER MENTION THROUGH MUCH OF THE TIME PERIOD.
BY MID DAY SUNDAY...THE UPPER TROUGH AXIS SHOULD BE EAST OF THE
CWA...ALLOWING PCPN TO END FROM WEST TO EAST. THE 12Z ECMWF REALLY
WRAPS THIS SYSTEM UP...WITH NORTHWESTERLY 850MB WINDS ON THE
ORDER OF 65KTS SUNDAY AFTERNOON. 850MB TEMPERATURES DO APPROACH
THE 0C MARK OF THE LATEST ECMWF SO WILL NEED TO WATCH THAT
CAREFULLY FOR ANY CHANGE OVER IN PCPN TYPES SUNDAY.
MUCH COOLER NORTHWESTERLY FLOW WILL PERSIST ACROSS THE AREA THROUGH
EARLY NEXT WEEK WHICH MAY PUT TEMPERATURES INTO THE BELOW NORMAL
CATEGORY. A FEW MINOR WAVES MAY MOVE THROUGH THIS FLOW PROVIDING
SMALL CHANCES FOR PCPN.
&&
.AVIATION...(06Z TAFS FOR KOFK...KLNK AND KOMA.)
ISSUED AT 1146 PM CDT WED APR 15 2015
GENERALLY MVFR CIGS ARE EXPECTED OVERNIGHT AT THE TAF SITES. THE
BNK-OVC DECKS SHOULD CONT THROUGH THE DAY ON THU AS WELL BUT
INCREASE TO VFR /FL0040-050/ BY MID TO LATE MRNG. WE WILL CONT TO
LEAVE THE TAFS DRY AT THE MOMENT AS PRECIP TIMING AND CONFIDENCE
IS PRETTY LOW AT THIS POINT. IT WOULD APPEAR THAT THERE COULD BE
SOME MRNG SHRA AT KLNK...AND THEN SOME ISO LATE AFTN -SHRA AT ALL
SITES BUT COVERAGE IS EXPECTED TO BE LOW. OTHERWISE SOUTHEAST
WINDS...GENERALLY BELOW 12 KT...WILL CONT THROUGH THU EVNG.
&&
.OAX WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
IA...NONE.
&&
$$
SHORT TERM...DEE
LONG TERM...KERN
AVIATION...BOUSTEAD
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
134 AM EDT THU APR 16 2015
.SYNOPSIS...
LOW PRESSURE WILL DEVELOP ALONG A FRONT STALLED ALONG THE GEORGIA
COAST TONIGHT...SLOWLY WEAKENING LATE THURSDAY AND FRIDAY. HIGH
PRESSURE OVER NEW ENGLAND WILL SHIFT EAST AND OFFSHORE THURSDAY. A
WARM FRONT WILL MOVE NORTH THROUGH THE CAROLINAS ON SUNDAY WITH A
COLD FRONT TO FOLLOW MONDAY NIGHT INTO TUESDAY.
&&
.NEAR TERM /UNTIL 6 AM THIS MORNING/...
AS OF 130 AM THURSDAY...NO CHANGES TO THE FORECAST WITH THE LATEST
UPDATE. PREVIOUS DISCUSSION FOLLOWS:
THE WEATHER SITUATION IS UNFOLDING PRETTY MUCH AS EXPECTED. THE
SOLID MASS OF RAIN HAS CLEARED THE PEE DEE COUNTIES BUT RAIN
CONTINUES TO FALL ACROSS WHITEVILLE...SOUTHPORT AND WILMINGTON.
THIS AREA SHOULD MOVE OFF THE COAST IN THE NEXT 2 HOURS...LEAVING
MUCH WEAKER FORCING FOR THE OVERNIGHT NIGHT. LATEST HRRR AND HRRRMODELS
STILL SUGGEST THE BEST POTENTIAL FOR OVERNIGHT RAIN WILL BE NORTH
OF A LINE FROM FLORENCE TO DILLON...TO ELIZABETHTOWN AND
BURGAW...COINCIDENT WITH THE BETTER 700 MB MOISTURE AND RESIDUAL
ISENTROPIC LIFT ON THE SYNOPTIC MODELS. THERE IS ALSO SMALL
POSITIVE ELEVATED INSTABILITY ON THE ORDER OF 100 J/KG WHICH COULD
HELP SUPPORT SHOWERS GIVEN SUFFICIENT SYNOPTIC TRIGGERING. FEW
CHANGES ARE NEEDED TO LOW TEMPERATURE FORECASTS OR WINDS.
DISCUSSION FROM 730 PM FOLLOWS...
A STALLED FRONT JUST SOUTH OF SAVANNAH WILL DEVELOP AN AREA OF LOW
PRESSURE IN THE NEXT FEW HOURS. THIS LOW WILL NOT STRAY TOO FAR
OFFSHORE OVER THE NEXT 24 HOURS...BUT WILL MAINTAIN A STEADY
NORTHEAST WIND. SURFACE HIGH PRESSURE OVER SOUTHEASTERN CANADA
WILL SLIDE SOUTHEAST INTO NEW ENGLAND TONIGHT. THIS HIGH WILL
EXTEND A RIDGE AXIS SOUTHWARD INTO THE CAROLINAS...COMPRESSING THE
PRESSURE GRADIENT UP AGAINST THE LOW DEVELOPING OFF THE GEORGIA
COAST.
A COMPLEX UPPER LEVEL PATTERN ACROSS THE WESTERN U.S. HAS THE JET
STREAM SPLIT INTO TWO SEGMENTS. THE SOUTHERN STREAM WILL BRING
SEVERAL DISTURBANCES ACROSS THE CAROLINAS OVER THE NEXT 36-48
HOURS. ONE OF THESE DISTURBANCES IS MOVING ACROSS INTERSTATE 95
NOW PRODUCING THE LARGE SWATH OF RAIN NOW SEEN ON RADAR. THIS
FEATURE SHOULD WORK ITS WAY TO THE COAST AROUND MIDNIGHT...AND I
HAVE RAISED FORECAST POPS TO 100 PERCENT AREA-WIDE WITH 0.2 TO 0.4
INCHES OF RAIN EXPECTED OVER THE NEXT 12 HOURS. PLENTY OF MID-
LEVEL MOISTURE SHOULD HANG AROUND AFTER MIDNIGHT WITH JUST ENOUGH
WEAK ISENTROPIC LIFT PLUS ELEVATED INSTABILITY TO MAINTAIN SHOWERS
AFTER MIDNIGHT...ESPECIALLY NORTH OF FLORENCE AND MYRTLE BEACH.
LOW-LEVEL NORTHEAST WINDS WILL DRAG COOLER AIR SOUTHWARD
TONIGHT...WITH LOWS AWAY FROM THE COAST FALLING TO NEAR 50.
VARYING DEGREES OF MARINE INFLUENCE WILL KEEP THE IMMEDIATE COAST
WARMER WITH LOWS IN THE MID 50S POSSIBLE.
&&
.SHORT TERM /6 AM THIS MORNING THROUGH FRIDAY NIGHT/...
AS OF 300 PM WEDNESDAY...THE FORECAST HAS BECOME NO LESS COMPLICATED
AND IN FACT...IN SOME RESPECTS...MODELS HAVE DIVERGED EVEN FURTHER
IN THE LAST 24 HOURS. THE GFS SOLUTION LOOKS VERY DIFFERENT FROM
PREVIOUS RUNS. THE NAM SOLUTION LOOKS SIMILAR TO PREVIOUS
THINKING...BUT THE PROGRESSION OF OFFSHORE LOW PRESSURE IS SLOWER
AND FURTHER EASTWARD THAN 24 HOURS AGO AND CERTAINLY MUCH STRONGER.
THE CANADIAN IS CONSIDERABLY SLOWER AND WEAKER THAN THE NAM AS IS
THE EUROPEAN...BUT BOTH DO CLOSE OFF LOW PRESSURE ALONG THE COAST OF
SOUTH CAROLINA. SLOWER SEEMS REASONABLE GIVEN THE STRENGTH OF HIGH
PRESSURE TO THE NORTH AND RESULTING WEDGE...THUS THE BEST WE CAN DO
AT THIS POINT IS TO GO ALONG WITH PERSISTENCE...BUT SLOW PROGRESSION.
WILL INCLUDE HIGHEST POPS THU ALONG THE COAST AND UP TO CATEGORICAL
THU MORNING ALONG THE CAPE FEAR COAST DUE TO STRENGTH OF ISENTROPIC
LIFT COUPLED WITH THE LIFT ASSOCIATED WITH LOW PRESSURE/TROUGH. WILL
THEN TREND POPS LOWER THU AFTERNOON AND NIGHT FROM SW TO NE WITH A
LINGERING RISK ALONG THE CAPE FEAR COAST FRI MORNING. GIVEN
PROXIMITY OF COASTAL TROUGH AND ELEVATED INSTABILITY...WILL INCLUDE
MENTION OF THUNDER FOR PORTIONS OF THE FORECAST AREA.
THE MOISTURE PROFILES DRY OUT CONSIDERABLY AS A RIDGE OF HIGH
PRESSURE ALOFT BUILDS TO THE COAST FROM THE WEST TOWARD THE END OF
THE PERIOD. WILL FINALLY DROP POPS BELOW THRESHOLD FRI AFTERNOON AND
NIGHT...EVEN ALONG THE SEABREEZE BOUNDARY.
BELOW NORMAL HIGH TEMPS ARE EXPECTED AGAIN ON THU AS WEDGE KEEPS LOW-
LEVEL MOISTURE TRAPPED BENEATH INVERSION. HIGHS WILL ONLY BE IN THE
LOWER TO MID 60S. DEVELOPING SUNSHINE ON FRI SHOULD ALLOW TEMPS TO
RETURN TO MORE SEASONABLE LEVELS...LOW AND MID 70S. LOWS THIS PERIOD
WILL BE MAINLY IN THE 50S.
&&
.LONG TERM /SATURDAY THROUGH WEDNESDAY/...
AS OF 300 PM WEDNESDAY...GUIDANCE HAS SHIFTED PRETTY DRAMATICALLY
FROM JUST YESTERDAY...LEADING TO ENHANCED UNCERTAINTY DURING THE
EXTENDED. LARGE CLOSED LOW ACROSS THE SOUTHWEST WILL ONLY VERY
SLOWLY FILL AND EJECT TO THE NORTHEAST THROUGH THE WEEKEND...PHASING
WITH A DEEPENING NORTHERN STREAM CUTOFF LOW ACROSS THE GREAT LAKES
LATE MONDAY. THIS FEATURE WILL THEN AMPLIFY AND STALL ACROSS THE
GREAT LAKES THROUGH THE MIDDLE OF NEXT WEEK...PRODUCING 500MB
HEIGHTS OF -2 TO -3 SD`S BELOW CLIMO ACROSS THE NORTHEAST AND INTO
THE MID-ATLANTIC.
INITIALLY THE EXTENDED WILL BE WARM AND PLEASANT. SATURDAY IS
SHAPING UP TO BE A GORGEOUS DAY LOCALLY...WITH HIGHS ABOVE CLIMO AND
A LOT OF SUNSHINE. MOISTURE RETURNS SUNDAY IN A PRE-FRONTAL AIR MASS
WHICH WILL CONTINUE INTO MONDAY AHEAD OF A COLD FRONT. SUNDAY AND
MONDAY WILL BOTH FEATURE ABOVE CLIMO TEMPS...BUT WITH INCREASING
RAIN CHANCES AHEAD OF THE COLD FRONT. ATTM THE FRONT DOES NOT LOOK
TO BE STRONGLY FORCED SO WIDESPREAD CONVECTION IS NOT ANTICIPATED
MONDAY EVENING WITH THE FROPA. COOLER HIGH PRESSURE WILL BUILD IN
BEHIND THE FRONT FOR TUE/WED OF NEXT WEEK WITH TEMPS RETURNING TO
SEASONABLE LEVELS.
&&
.AVIATION /06Z THURSDAY THROUGH MONDAY/...
AS OF 06Z...EXPECTING IFR CONDITIONS MUCH OF THE TAF PERIOD WITH
OCCASIONAL RAIN. COULD BE A BREAK IN THE 20 TO 02Z WINDOW WITH
MVFR OR VFR CONDITIONS UNTIL THE NEXT BATCH OF PRECIPITATION
ARRIVES TOWARD THE END OF THE PERIOD. WITH LOW PRESSURE OFF THE
COAST...GUSTY NE WINDS ARE EXPECTED THROUGH MUCH OF THE PERIOD AS
WELL WITH SPEEDS IN THE 10 TO 15 KT RANGE WITH WITHS OVER 20
KT...ESPECIALLY COASTAL TERMINALS.
EXTENDED OUTLOOK...PREDOMINATELY IFR CONDITIONS ARE EXPECTED INTO
EARLY FRIDAY MORNING WITH THE WEDGE. IMPROVING CONDITIONS DURING THE
DAY FRI. DETERIORATING CONDITIONS AGAIN SATURDAY NIGHT THROUGH
SUNDAY WITH A SLOW MOVING FRONT. SLIGHT CHANCE FOR SHOWERS MONDAY.
&&
.MARINE...
NEAR TERM /THROUGH TONIGHT/...
AS OF 130 AM THURSDAY...NO CHANGES TO THE FORECAST WITH THE LATEST
UPDATE. PREVIOUS DISCUSSION FOLLOWS:
STRONG NE WINDS HAVE QUICKLY DEVELOPED THIS EVENING. RECENT WIND
GUSTS INCLUDE 31 KNOTS AT SPRINGMAID PIER IN MYRTLE BEACH...24
KNOTS ON BALD HEAD ISLAND...AND 23 KNOTS AT WRIGHTSVILLE BEACH.
SEAS OUT AT THE FRYING PAN SHOALS BUOY HAVE ALREADY REACHED 8
FEET...WITH SEAS NOW PASSING 5 FEET AT BOTH NEARSHORE BUOYS NEAR
CAPE FEAR. THIS UPDATE BACKED WINDS AROUND MORE NORTHERLY
NEARSHORE AND INCREASE SEA HEIGHTS SLIGHTLY...ALL BASED ON CURRENT
OBSERVATIONS. DISCUSSION FROM 730 PM FOLLOWS...
A FRONT STALLED JUST SOUTH OF SAVANNAH EXTENDS EAST WELL OFF THE
COAST. WEAK LOW PRESSURE WILL DEVELOP ALONG THE FRONT
TONIGHT...WHILE HIGH PRESSURE OVER NEW ENGLAND RIDGES SOUTHWARD
DOWN THE COAST. THE CAROLINAS WILL BE CAUGHT IN BETWEEN THESE TWO
SYSTEMS...WITH INCREASING EAST-NORTHEAST WINDS THE RESULT.
THE 18Z GFS APPEARS TO BE THE BEST INITIALIZED OF OUR MODELS THIS
EVENING...AND ITS FORECAST WINDS HAPPEN TO BE THE STRONGEST
TONIGHT...INDICATING WINDS NEARSHORE INCREASING TO 20-25 KT AND
25-30 KT AWAY FROM SHORE. THIS IS SLIGHTLY HIGHER THAN THE
PREVIOUS FORECAST HAD. LATEST CHECK OF BUOYS INDICATES SEAS ARE
INCREASING A BIT FASTER THAN EARLIER THOUGHT. I HAVE ADDED ABOUT
ONE FOOT TO THE PREVIOUS FORECAST...WITH SEAS NOW EXPECTED TO
BUILD TO 6-8 FEET OUT AT 20 MILES DISTANCE FROM SHORE...WITH 4-7
FEET EXPECTED CLOSER TO SHORE.
SHORT TERM /THURSDAY THROUGH FRIDAY NIGHT/...
AS OF 300 PM WEDNESDAY...ONGOING SMALL CRAFT ADVISORY CONDITIONS ARE
EXPECTED AT THE BEGINNING OF THE PERIOD AS LOW PRESSURE MOVES UP THE
SOUTHEAST COAST. THE PRESSURE GRADIENT BETWEEN DEVELOPING LOW
PRESSURE AND THE STRONG HIGH TO THE NORTH WILL ALLOW A TIGHT
PRESSURE GRADIENT TO PERSIST INTO THU AND THIS IS WHEN WE EXPECT THE
STRONGEST WINDS AND HIGHEST SEAS...UP TO 20 TO 30 KT...HIGHEST
NORTHERN WATERS AND SEAS UP TO 5 TO 8 FT THROUGHOUT. AS THE PRESSURE
GRADIENT SLACKENS AND LOW PRESSURE MOVES TO OUR N...WINDS AND SEAS
WILL SUBSIDE THU NIGHT AND FRI WITH THIS TREND PERSISTING INTO FRI
NIGHT. ENE WINDS THU WILL BACK TO NE THU NIGHT WITH NNE TO NE
WINDS THEN PERSISTING THROUGH THE END OF THE PERIOD.
LONG TERM /SATURDAY THROUGH MONDAY/...
AS OF 300 PM WEDNESDAY...HIGH PRESSURE WILL BUILD DOWN THE COAST AND
THEN MOVE OFFSHORE SATURDAY...CREATING A WEAK PRESSURE GRADIENT AND
WINDS SHIFTING FROM NE EARLY...TO E/SE LATE. WINDS SPEEDS THEN
STEADILY INCREASE SUNDAY AS THE GRADIENT STARTS TO PINCH AHEAD OF AN
APPROACHING COLD FRONT...BECOMING S/SW AT AROUND 15 KTS MOST OF
SUNDAY...AND THEN SW AT 15-20 KTS ON MONDAY DIRECTLY AHEAD OF THE
FROPA. COLD FRONT WILL CROSS THE WATERS AT THE VERY END OF THE
PERIOD WITH A WIND SHIFT TO THE NW AT 10-15 KTS. ALTHOUGH A WEAK SE
GROUND SWELL WILL BE PRESENT IN THE SPECTRUM DURING THE
EXTENDED...MUCH OF THE WAVE AMPLITUDE WILL BE FORMED VIA WIND
WAVES...AND SEAS WILL BE 2-3 FT SATURDAY...BUILDING TO 3-5 FT SUNDAY
AND MONDAY AHEAD OF THE COLD FRONT.
&&
.ILM WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
NC...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 6 AM EDT FRIDAY FOR AMZ250-252-254-
256.
&&
$$
SYNOPSIS...RJD
NEAR TERM...REK/TRA
SHORT TERM...RJD
LONG TERM...JDW
AVIATION...RAN
MARINE...REK/RJD/TRA/JDW
AREA FORECAST DISCUSSION
NWS BISMARCK ND
1227 AM CDT THU APR 16 2015
.UPDATE...
ISSUED AT 1227 AM CDT THU APR 16 2015
MINOR CHANGES THIS UPDATE. KEPT CHANCES OF RAIN SHOWERS
SOUTHWEST...BUT APPARENT FORCING ALONG THE SLOW-MOVING COLD FRONT IN
CENTRAL NORTH DAKOTA IS NOT ENOUGH TO SUSTAIN SHOWERS. MINOR CHANGES
IN HOURLY TEMPERATURE TRENDS.
UPDATE
ISSUED AT 923 PM CDT WED APR 15 2015
RADAR ECHOS ACROSS THE FAR SOUTHWEST...OTHERWISE DRY SO ONCE AGAIN
SCALED BACK ON POPS FOR THIS UPDATE. OTHER EDITS MINOR.
UPDATE
ISSUED AT 808 PM CDT WED APR 15 2015
WILL ALLOW THE RED FLAG TO EXPIRE AS SCHEDULED WITH WINDS TAPERING
OFF AND RH VALUES QUICKLY INCREASING.
UPDATE
ISSUED AT 720 PM CDT WED APR 15 2015
SCALED BACK ON POPS A BIT WITH A VOID OF ANY SORT OF DECENT RADAR
RETURNS ACROSS NORTH DAKOTA. ALLOWED THE WIND ADVISORY TO EXPIRE
AS WE ARE NOW BELOW ADVISORY CRITERIA EAST...AND WITH WINDS
EXPECTED TO QUICKLY TAPER OFF FURTHER OVER THE NEXT HOUR OR SO.
STRONG UPPER LEVEL LOW PRESSURE CONTINUES TO SPIN JUST WEST OF THE
CENTRAL ROCKIES. ENERGY ROTATING AROUND THE LOW WILL SPIRAL NORTH
ACROSS THE WESTERN DAKOTAS AND SHOULD BRING SOME LIGHT RAIN. BAND
OF ENHANCED RADAR RETURNS CURRENTLY LIFTING NORTH ACROSS WESTERN
SOUTH DAKOTA TOWARDS MY SOUTHWEST. WITH T/TD SPREADS
20-30F...WILL KEEP POPS BELOW LIKELY FOR NOW AND CONTINUE TO
MONITOR.
RED FLAG WARNING WILL BE ALLOWED TO EXPIRE AT 01Z...ROUGHLY 45-50
MINUTES FROM NOW...AS WINDS TAPER OFF AND RH VALUES INCREASE.
&&
.SHORT TERM...(THIS EVENING THROUGH THURSDAY)
ISSUED AT 251 PM CDT WED APR 15 2015
FIRE WEATHER CONCERNS HIGHLIGHT THE SHORT TERM TONIGHT BUT WILL
DIMINISH TOMORROW. A COLD FRONT ACROSS WESTERN NORTH DAKOTA HAS
BEEN SLOWER TO MOVE EAST THAN EARLIER FORECAST. THE RESULT HAS
BEEN AN EXTENDED PERIOD OF GUSTY SOUTHERLY WINDS ACROSS CENTRAL
AND EASTERN NORTH DAKOTA UP THROUGH THIS AFTERNOON. THIS HAS
RESULTED AN MULTIPLE FIRES ACROSS CENTRAL NORTH DAKOTA. IMPROVING
CONDITIONS WILL FINALLY ARRIVE THIS EVENING AS THE FRONTAL
BOUNDARY MOVES TO CENTRAL NORTH DAKOTA THEN TO THE EAST AFTER
MIDNIGHT. THIS WILL BRING AN END TO THE STRONG SOUTHERLY WINDS.
CLOUDS ARE BEING DRAWN UP THROUGH EASTERN SOUTH DAKOTA WITH SOME
LIMITED LOW LEVEL MOISTURE. THE HRRR DOES GENERATE SOME LIGHT
PRECIP ACROSS THE EAST...BUT GENERALLY EAST OF THE JAMES RIVER
VALLEY THOUGH.
MEASURABLE PRECIPITATION WILL BE MOST LIKELY ACROSS THE SOUTHWEST
TONIGHT. BUT KEPT THE POPS LESS THAN 40 PERCENT.
ON THURSDAY...COOLER TEMPERATURES WITH HIGHS 60 TO 65.
.LONG TERM...(THURSDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 251 PM CDT WED APR 15 2015
A WEAK COLD FRONTAL BOUNDARY SHIFTING THROUGH NORTHERN NORTH DAKOTA
LATE THURSDAY NIGHT WILL UNDERGO FRONTOLYSIS AS IT SAGS SOUTH INTO
CENTRAL NORTH DAKOTA FRIDAY MORNING. SPLIT FLOW REMAINS OVER NORTH
DAKOTA FRIDAY WITH THE NORTHERN STREAM JUST GRAZING FAR NORTHERN
NORTH DAKOTA/TURTLE MOUNTAINS. A CLOSED LOW OVER COLORADO SLOWLY
EMERGES INTO THE CENTRAL PLAINS...WITH NORTH DAKOTA CAUGHT BETWEEN
THESE TWO STREAMS FRIDAY AND WILL MOSTLY REMAIN IN A LULL FRIDAY
WITH BENIGN WEATHER. FOR SATURDAY AND SATURDAY NIGHT...MODEL DATA
CONTINUES TO SUGGEST SOME INTERACTION WITH THE CLOSED LOW AND ITS
ASSOCIATED MOISTURE SPINNING INTO SOUTHERN NORTH DAKOTA...AND A
STRONG SHORTWAVE TROUGH/SURFACE COLD FRONT VIA THE NORTHERN STREAM
AS IT APPROACHES WESTERN NORTH DAKOTA 00Z SUNDAY. VARYING SOLUTIONS
AS TO THE TIMING AND AREAL COVERAGE OF PRECIPITATION THAT IS
FORECAST TO PUSH INTO NORTH DAKOTA SATURDAY AFTERNOON INTO SATURDAY
NIGHT. THE GFS REPRESENTS THE FASTEST AND MOST WIDESPREAD
PRECIPITATION SOLUTIONS...WITH CHANCES OF RAIN CROSSING THE SOUTHERN
BORDER BEFORE 12Z SATURDAY. THE GEM/ECMWF REPRESENT SLOWER SOLUTIONS
AND ARE MORE IN LINE WITH RAIN SHOWERS MAINLY CONFINED TO THE JAMES
RIVER VALLEY AND PORTIONS OF SOUTH CENTRAL NORTH DAKOTA LATE
SATURDAY AFTERNOON THROUGH SUNDAY MORNING. A COLD THERMAL
TROUGH/POCKET IS FORECAST TO FOLLOW SUNDAY NIGHT THROUGH MOST OF
NEXT WEEK. GOOD AGREEMENT BETWEEN THE GFS AND ECMWF WITH THIS IDEA.
850MB TEMPS ARE FORECAST TO RANGE BETWEEN -2C TO -8C THROUGH
THURSDAY. THIS WILL TRANSLATE TO AFTERNOON HIGH TEMPERATURES IN THE
UPPER 40S TO MID 50S.
CONCERNING FIRE WEATHER IN THE LONG TERM PERIOD...NOT ANTICIPATING
ANY FIRE WEATHER CONCERNS FRIDAY OR SATURDAY. DESPITE A COOLING
TREND SUNDAY ONWARD...STRONG WINDS AT TIMES WILL ALIGN WITH LOW
RELATIVE HUMIDITIES ACROSS PORTIONS OF WESTERN AND CENTRAL NORTH
DAKOTA AND WILL NEED TO MONITOR. STRONG NORTHWEST WINDS DEVELOPING
BEHIND A COLD FRONT ACROSS WESTERN AND CENTRAL NORTH DAKOTA SUNDAY
MAY WARRANT A WIND ADVISORY. IN ADDITION MINIMUM RELATIVE HUMIDITIES
OF AROUND 25 PERCENT IN THE SOUTHWEST MAY ALSO WARRANT A FIRE
WEATHER HEADLINE SUNDAY. THEN ON MONDAY THE STRONGEST WINDS AND
LOWEST RELATIVE HUMIDITIES ARE ALIGNED IN SOUTH CENTRAL NORTH
DAKOTA...THUS THIS REPRESENTS ANOTHER POTENTIAL FOR FIRE WEATHER
HEADLINES. WEAKER WINDS ARE EXPECTED FOR TUESDAY AND WEDNESDAY WITH
EVEN COOLER TEMPERATURES...WITH WIDESPREAD HIGHS IN THE 40S
WEDNESDAY. NO SIGNIFICANT SYSTEMS/PRECIPITATION EVENTS SUNDAY
THROUGH WEDNESDAY.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z THURSDAY NIGHT)
ISSUED AT 1227 AM CDT THU APR 16 2015
A COLD FRONT EXTENDED FROM NEAR BOTTINEAU/RUGBY TO NEAR KBIS TO KMBG
WAS SLOWLY PROPAGATING EASTWARD ACROSS THE STATE. SOUTHERLY WINDS AT
KJMS SHOULD BECOME NORTHWESTERLY AROUND 12Z. OTHERWISE NORTH TO
NORTHWEST WINDS AT TAF SITES MUCH OF TODAY...BECOMING LIGHT AFT 00Z.
VFR CIGS/VSBYS ARE EXPECTED THROUGHOUT THE PERIOD.
&&
.FIRE WEATHER...
ISSUED AT 808 PM CDT WED APR 15 2015
RED FLAG WARNING ALLOWED TO EXPIRE WITH COOLING TEMPERATURES AND
RISING RELATIVE HUMIDITY. ON THURSDAY MINIMUM RELATIVE HUMIDITY
WILL FALL INTO THE UPPER TEENS NORTHWEST. HOWEVER THE WINDS WILL
BE MUCH LOWER.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...JV
SHORT TERM...WAA
LONG TERM...KS
AVIATION...JV
FIRE WEATHER...NH
FORECAST DISCUSSION FOR ROUTINE MORNING FORECAST ISSUANCE
.SHORT TERM...TODAY...TONIGHT...AND FRIDAY
ISSUED AT 257 AM CDT THU APR 16 2015
THE LATEST RAP ANALYSIS AND SATELLITE/RADAR IMAGERY SHOW HIGH
PRESSURE CENTERED OVER THE EAST COAST...BUT WITH A RIDGE AXIS
EXTENDING WEST TO THE WESTERN GREAT LAKES. VERY DRY AIR CONTINUES TO
HOLD ON ACROSS THE REGION...AND DEWPOINTS HAVE STRUGGLED TO RECOVER
OVER CENTRAL AND NORTH-CENTRAL WISCONSIN OVERNIGHT. SOUTHEAST LOW
LEVEL FLOW OVER THE SOUTHERN GREAT LAKES IS SLOWLY VEERING TO MORE
OF A SOUTHERLY DIRECTION...BUT IS STILL TRYING TO PUSH LIGHT SHOWER
ACTIVITY ACROSS SOUTH-CENTRAL LAKE MICHIGAN. THIS IS AHEAD OF A
SHORTWAVE OVER THE IL/IN BORDER. THE BONE DRY AIRMASS AND VEERING
FLOW IS NOT HELPING THESE SHOWERS TO MAKE A WESTWARD JAUNT...AND THE
LATEST MESOMODELS KEEP THESE SHOWERS EAST OF THE MANITOWOC SHORELINE
EARLY THIS MORNING. THIS SHOWER ACTIVITY ALONG WITH FIRE WEATHER
CONDITIONS ARE THE MAIN FORECAST CONCERNS IN THE SHORT TERM.
TODAY...THE SHORTWAVE OVER THE IL/IN BORDER WILL LIFT NE THIS
MORNING AND THEN EAST THIS AFTERNOON AS RIDGING OVER THE GREAT LAKES
FLATTENS. 850MB FLOW WILL CONTINUE TO VERY GRADUALLY VEER THIS
MORNING WHICH COMBINED WITH THE VERY DRY AIR ACROSS THE REGION WILL
GIVE THE LIGHT SHOWER ACTIVITY OVER SOUTHERN LAKE MICHIGAN A SUBTLE
PUSH TO THE EAST. SO WILL KEEP THE DRY FORECAST IN TACT...BUT WILL
INCREASE CLOUD COVER OVER EAST-CENTRAL WISCONSIN TODAY AS 5K-6KFT
CLOUDS OVER NORTHERN ILLINOIS WILL LIKELY ARRIVE THIS MORNING.
ELSEWHERE...A MID-LEVEL DECK OVER MINNESOTA AND IOWA WILL SHIFT TO
THE EAST AND MOVE INTO NORTH-CENTRAL WISCONSIN DURING THE
AFTERNOON. UNTIL THESE CLOUDS ARRIVE...A POCKET OF VERY DRY AIR
WILL REMAIN IN PLACE ACROSS CENTRAL AND NORTH-CENTRAL WISCONSIN.
MIXING WILL NOT BE AS GOOD TODAY DUE TO LIGHTER WINDS ALOFT...BUT
STILL LOWERED DEWPOINTS SINCE THINK WILL STILL BE ABLE TO TAP INTO
SOME OF THE BONE DRY AIR JUST ABOVE THE INVERSION. AS A
RESULT...HAVE DROPPED DEWPOINTS AND HUMIDITIES OVER CENTRAL AND
NORTH-CENTRAL WISCONSIN THIS AFTERNOON. HUMIDITIES COULD FALL
BETWEEN 20-25 PCT. FORTUNATELY...WINDS WILL BE MUCH LIGHTER
TODAY...SO SHOULD NOT SEE A REPEAT OF THE CRITICAL FIRE WEATHER
CONDITIONS. HIGHS MAINLY IN THE MID TO UPPER 60S AWAY FROM LAKE
MICHIGAN.
TONIGHT...A COLD FRONT WILL DECAY AS IT MOVES INTO NORTH-CENTRAL
WISCONSIN LATE. MID-LEVEL CLOUDS WILL CONTINUE TO SPREAD EAST AHEAD
OF THE FRONT...BUT GRADUALLY DISSIPATE IN THE PROCESS. SHOULD
THEREFORE SEE A PARTLY CLOUDY TO MOSTLY CLEAR NIGHT. WITH THE
THINNING CLOUDS...DO NOT THINK THERE WILL BE A DEEP ENOUGH CLOUD
LAYER FOR SPRINKLES OR LIGHT SHOWERS. LOWS MAINLY IN THE LOW TO MID
40S.
FRIDAY...THE FRONT WILL WASH OUT ACROSS NORTHERN WISCONSIN. MAY SEE
SOME CU DEVELOP OVER CENTRAL AND EAST-CENTRAL WISCONSIN DURING THE
AFTERNOON...BUT THE NORTH SHOULD SEE AN INFLUX OF DRY AIR...THAT
WILL DROP HUMIDITIES NEAR 25 PCT IN THE AFTERNOON. HIGHS WILL BE
WARMER THAN TODAYS READINGS...AND RAISED THEM INTO THE UPPER 60S
NORTH TO MID 70S SOUTH.
.LONG TERM...FRIDAY NIGHT THROUGH WEDNESDAY
ISSUED AT 257 AM CDT THU APR 16 2015
DRY CONDITIONS WILL CONTINUE FRIDAY NIGHT AND SATURDAY AS CANADIAN
HIGH PRESSURE BUILDS INTO THE STATE. NORTHWEST WINDS WILL TURN
TO THE EAST AND NORTHEAST LATE FRIDAY NIGHT AND SATURDAY. SATURDAY
AFTERNOON WILL AGAIN FEATURE VERY LOW AFTERNOON RELATIVE HUMIDITY
READINGS AWAY FROM THE LAKE...WITH READINGS DROPPING INTO THE 20
TO 40 PERCENT RANGE WITH THE LOWEST READINGS NORTH AND WEST OF THE
FOX VALLEY.
MEANWHILE...CLOSED UPPER LOW ACROSS THE CENTRAL PLAINS IS EXPECTED
TO OPEN UP AS 500MB TROUGH ACROSS SOUTHERN CANADA WILL BEGIN TO
LIFT THE SOUTHERN SYSTEM NORTHEAST TOWARDS THE REGION. QUIET A
SPREAD IN THE MODELS ON HOW QUICK THE RAIN WILL ARRIVE OVER THE
WEEKEND. THE WRF MODELS WAS QUICKEST...ALREADY BRINGING RAIN ON
SATURDAY TO PORTIONS OF THE AREA. THE GFS MODEL WAS IN THE MIDDLE
OF THE ROAD SOLUTION...WHILE THE CANADIAN/ECMWF MODEL WERE THE SLOWEST
SOLUTION WITH RAIN ARRIVING ON SUNDAY. TRENDED TOWARD THE SLOWER
SOLUTION FOR THE MEANTIME DUE TO BETTER CONSISTENCY FROM RUN TO
RUN. DID ADD A SMALL CHANCE OF RAIN ACROSS THE WEST LATE SATURDAY
NIGHT...AND THEN BOOSTED RAIN CHANCES INTO THE LIKELY CATEGORY ON
SUNDAY. DID RAISE RAIN CHANCES SUNDAY NIGHT AS WELL. THE 500MB
SYSTEMS WILL MERGE INTO A CLOSED UPPER LOW ACROSS THE UPPER
MIDWEST AND WESTERN GREAT LAKES REGION EARLY NEXT WEEK. THIS
WOULD SUPPORT A COOLER AND UNSETTLED PATTERN ACROSS THE REGION
ON MONDAY THROUGH WEDNESDAY. HAVE CHANCES OF SHOWERS EACH PERIOD...
ALONG WITH A LITTLE SNOW LATE AT NIGHT INTO THE EARLY MORNING
HOURS ON TUESDAY AND WEDNESDAY. IT IS WISCONSIN! TEMPERATURES
BY EARLY NEXT WEEK WILL RUN WELL BELOW NORMAL.
&&
.AVIATION...FOR 06Z TAF ISSUANCE
ISSUED AT 1021 PM CDT WED APR 15 2015
VFR CONDITIONS EXPECTED TONIGHT INTO THURSDAY. LIGHT EAST WIND AT
THE SURFACE WILL PREVAIL TONIGHT INTO THURSDAY BEFORE TURNING
VARIABLE OVER CENTRAL AND NORTH CENTRAL WISCONSIN WITH A WEAK
FRONTAL BOUNDARY. A WEAK DISTURBANCE WILL SLIDE OVER SOUTHEAST
WISCONSIN LATER TONIGHT INTO THURSDAY MORNING. A FEW SPRINKLES BUT
MORE THAN LIKELY VIRGA MAY FALL FROM A MID LEVEL DECK OF CLOUDS
OVER EAST CENTRAL WISCONSIN TOWARD THURSDAY MORNING.
&&
.GRB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM.....MPC
LONG TERM......ECKBERG
AVIATION.......TDH
AREA FORECAST DISCUSSION
NWS CHEYENNE WY
1046 PM MDT WED APR 15 2015
.UPDATE...
ISSUED AT 1034 PM MDT WED APR 15 2015
RADAR CONTINUES TO SHOW MOISTURE STREAMING NORTH OUT OF NORTHERN
COLORADO THIS EVENING. WITH REPORTS OF 5-6 INCHES OF SNOW IN
LARAMIE...WENT AHEAD AND EXPANDED THE ADVISORY SOUTH AS WE COULD
SEE ANOTHER 1-3 INCHES OVERNIGHT. ATTENTION TURNS TO THURSDAY
NIGHT AS LOW IN COLORADO SPINS OFF ANOTHER STRONGER PIECE OF
ENERGY INTO THE LARAMIE RANGE. GUIDANCE SHOWING QPFS WELL OVER AN
INCH BEGINNING THURSDAY AFTERNOON AND PERSISTING INTO FRIDAY
MORNING. WENT AHEAD WITH A WINTER STORM WATCH FOR THE
MOUNTAINS...ADJACENT FOOTHILLS AND THE SNOWY RANGE. UPDATES SENT
OUT EARLIER.
&&
.SHORT TERM...(THIS EVENING THROUGH FRIDAY NIGHT)
ISSUED AT 311 PM MDT WED APR 15 2015
TRICKY FORECAST THIS PERIOD WITH MAIN DIFFICULTIES BEING SNOW
LEVELS AND SNOWFALL AMOUNTS...AND AT WHAT TIMES THE HEAVIER
PRECIPITATION WILL OCCUR.
UPPER LOW TAKING SHAPE ALONG THE UTAH/COLORADO BORDER CURRENTLY
WITH AREAS OF RAIN AND SNOW ALONG AND WEST OF THE LARAMIE RANGE.
SOME CONVECTIVE ACTIVITY MOVING NORTH TOWARDS THE NEB PANHANDLE
FROM COLORADO AS WELL WITH A FEW LIGHTNING STRIKES NOTED IN THIS
ACTIVITY. EXPECT ALL THIS ACTIVITY TO CONTINUE MOVING NORTH AHEAD
OF AN IMPULSE RIDING UP THE EAST SIDE OF THE UPPER LOW THIS
EVENING THEN THERE SHOULD BE SOME LULL IN THE PCPN OVER THE
SOUTHERN PARTS OF THE CWA LATER THIS EVENING INTO THURSDAY BEHIND
THE IMPULSE WHILE THE MAIN UPPER LOW SINKS SLOWLY SOUTHWARD TO THE
4 CORNERS AREA. WILL MAINTAIN CURRENT WINTER WX ADVY AS IS AS THAT
AREA SHOULD STILL SEE MOSTLY SNOW.
CONDITIONS DETERIORATE AGAIN THURSDAY NIGHT AS THE UPPER LOW
DRIFTS SLOWLY ENE ACROSS COLORADO WITH NEXT SHORTWAVE LIKELY
ROTATING NORTH AND ACROSS THE CWA LATER THURSDAY NIGHT INTO
FRIDAY. HEAVIEST PCPN LOOKS LIKE IT WILL OCCUR THEN AND COULD GET
SOME DECENT SNOWS OVER HIGHER TERRAIN. 700MB TEMPS A BIT WARM
HOWEVER...ABOUT -2C...AND WARM GROUND MAY HINDER ACCUMULATIONS
SOME. WILL HOLD OFF ON ADDITIONAL HILITES AT THIS TIME AND LET
LATER SHIFTS LOOK AT NEWER RUNS. PCPN STILL FAIRLY WIDESPREAD ON
FRIDAY INTO FRIDAY NIGHT THOUGH MORE LIKELY OVER THE NORTH AS THE
IMPULSE CONTINUES TO RIDE NORTH AND NORTHWEST. SNOW LEVELS ALSO
RISING AS THE UPPER LOW FILLS SOME.
.LONG TERM...(SATURDAY THROUGH TUESDAY)
ISSUED AT 311 PM MDT WED APR 15 2015
UNSETTLED WEATHER WILL CONTINUE THROUGH THE WEEKEND AS A CLOSED LOW
TRANSLATES EASTWARD INTO THE CENTRAL PLAINS. PRECIPITATION IS LIKELY
TO LINGER THROUGH AT LEAST SUNDAY WITH WEAK MIDLEVEL ENERGY ROTATING
WESTWARD ACROSS THE CWA. FAIRLY COOL TOO WITH GFS 700 MILLIBAR TEMPS
FAILING TO CLIMB ABOVE 0 DEG C. THE MODELS ARE IN GOOD AGREEMENT W/
A KICKER SYSTEM DIVING INTO THE DAKOTAS AT 12Z SUN. THIS PUSHES THE
OTHER SYSTEM TO THE EAST AND SENDS A COLD FRONT SOUTH. MEDIUM RANGE
MODELS SHOW ENOUGH H7-H3 MOISTURE TO SUPPORT SHOWERS CONTINUING INTO
SUN. WOULD PROBABLY BE COLD ENOUGH FOR ALL SNOW ON SUN...BUT THERMAL
PROFILES WOULD SUGGEST ALL RAIN OR A RAIN/SNOW MIX FROM THE NE STATE
LINE INTO THE WESTERN PANHANDLE PRIOR TO FROPA. MAINTAINED LOWER END
POPS INTO EARLY NEXT WEEK WITH COOL CYCLONIC FLOW ALOFT. INSTABILITY
SHOWERS CANNOT BE RULED OUT...SO IT IS HARD TO FORECAST DRY. NOTHING
MAJOR THOUGH. TEMPERATURES SHOULD STAY ON THE COOL SIDE FOR MOST OF
THE PERIOD.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z THURSDAY NIGHT)
ISSUED AT 1034 PM MDT WED APR 15 2015
LATEST HRRR GUIDANCE USED FOR THE 06Z TAFS. WIDESPREAD IFR/LIFR
WITH NORTHEAST UPSLOPING FLOW. PRECIP BECOMES WIDESPREAD THURSDAY
AFTERNOON...WITH A POSSIBLE HEAVY SNOW EVENT THURSDAY NIGHT INTO
FRIDAY MORNING FOR SOUTHEAST WYOMING AND A WIDESPREAD MODERATE
RAIN EVENT FOR THE PANHANDLE AIRPORTS.
&&
.FIRE WEATHER...
ISSUED AT 311 PM MDT WED APR 15 2015
CONCERNS EXPECTED TO BE LOW THROUGH THE WEEKEND AS A COOL TO MILD
AIRMASS WILL RESIDE OVER THE DISTRICTS WITH PERIODS OF RAIN OR
SNOW BRINGING WETTING PRECIPITATION TO MUCH OF THE AREA.
&&
.CYS WATCHES/WARNINGS/ADVISORIES...
WY...WINTER STORM WATCH FROM THURSDAY EVENING THROUGH FRIDAY
AFTERNOON FOR WYZ103-105>107-110-114>118.
WINTER WEATHER ADVISORY UNTIL 9 AM MDT THURSDAY FOR WYZ101-
103>106-109-110-115>117.
NE...NONE.
&&
$$
UPDATE...GCC
SHORT TERM...RE
LONG TERM...CLH
AVIATION...GCC
FIRE WEATHER...RE
AREA FORECAST DISCUSSION
NWS GRAND JUNCTION CO
938 AM MDT THU APR 16 2015
.UPDATE...
ISSUED AT 936 AM MDT THU APR 16 2015
GRAND JCT RADAR INDICATED AN AREA OF ENHANCED PRECIPITATION ACROSS
WEST-CENTRAL CO THIS MORNING. MUCH OF THIS PRECIP WAS SNOW PER
PUBLIC REPORTS AND WEBCAM IMAGES. NOT EXPECTING ANY LONG-LASTING
ACCUMULATIONS IN THESE VALLEYS THOUGH PERIODS OF HEAVIER SNOW MAY
TEMPORARILY WHITEN GRASSY SURFACES. HI-RESOLUTION HRRR AND RAP
MODELS SHOW THIS AREA DECREASING...OR AT LEAST SLIDING NORTH AND
NORTHEAST...BY LATE MORNING. EXPECT TO SEE COVERAGE INCREASE ACROSS
ALL OF THE CENTRAL AND NORTHERN PORTIONS OF THE FORECAST AREA THIS
AFTERNOON AS CONVECTIVE INSTABILITY KICKS IN EVEN MORE.
LET THE FREEZE WARNING EXPIRE AT 9 AM THIS MORNING. SOME AREAS WHERE
SNOW IS OCCURRING MAY STILL BE IN THE UPPER 20S FOR A BIT LONGER
THOUGH...LIKE DELTA/MONTROSE/PAONIA AREAS. FREEZE WATCH REMAINS
FOR THE CORTEZ-YELLOWJACKET AREA EARLY FRI MORNING.
UPDATE ISSUED AT 613 AM MDT THU APR 16 2015
SOCIAL MEDIA REPORTS OF HOWLING WINDS IN THE STEAMBOAT SPRINGS
AREA HAVE BEEN RECEIVED EARLY THIS MORNING...PEAK GUSTS ON SENSORS
IN THE AREA SHOWING 25-35 MPH SO FAR THIS MORNING. PATTERN IS
SETTING UP FOR A POTENTIAL DOWNSLOPE WIND EVENT IN THIS REGION
LATER THIS AFTERNOON AND TONIGHT. STRONG H7 FLOW AROUND NORTH
SIDE OF THE LOW EXPECTED TO EXCEED 50 KTS AND WE HAVE SEEN THIS
TYPE OF FLOW IN THE PAST GENERATE STRONG DOWNSLOPE WINDS IN THE
STEAMBOAT AND ZIRKEL WILDERNESS AREAS. TRACK OF THE UPPER LOW WILL
PLAY CRITICAL ROLE AND MODELS STILL A BIT OUT OF PHASE IN EXACT
PATH...SO WILL CONTINUE TO MONITOR AND ADVISE LATER SHIFTS OF THIS
POTENTIAL. IN THE MEANTIME...BOOSTED SPEEDS UP A FEW CATEGORIES
FOR TODAY WITH GUSTS UP TO 50 MPH FOR THE HILLS AND GUST TO UP TO 45
FOR THE VALLEYS.
&&
.SHORT TERM...(TODAY THROUGH FRIDAY)
ISSUED AT 416 AM MDT THU APR 16 2015
SPRING IN THE CENTRAL ROCKIES IS REARING ITS UGLY HEAD AS
TEMPERATURES THIS MORNING HAVE DIPPED BELOW FREEZING IN MANY
LOCATIONS WHICH HAVE ALREADY BEGUN THEIR GROWING SEASONS...WHILE
OTHERS (THE EASTERN UINTAS) HAVE ALREADY SEEN A DECENT AMOUNT OF
ACCUMULATING SNOW. A LARGE CLOSED LOW IS CURRENTLY OVER SOUTHEAST
UTAH AND WILL SLOWLY PROGRESS SOUTH TO THE FOUR CORNERS LATER THIS
MORNING. MODELS ARE IN GOOD AGREEMENT THAT SIGNIFICANT SNOW IS
GOING TO FALL AT ELEVATIONS MAINLY HIGHER THAN 9000 FT STARTING
THIS AFTERNOON ACROSS THE WEST CENTRAL COLORADO MOUNTAINS AND WILL
CONTINUE TO FALL OVER THE EASTERN UINTAS. THOUGH WINDS WILL NOT BE
FAVORABLE FOR CONSTANT SNOWFALL DURING THE ENTIRE TIME PERIOD OF
THE WINTER HAZARDS...WHEN THE DIRECTION IS RIGHT COMBINED WITH
LIFTING DUE TO THE PASSING CLOSED LOW...HEAVY WET SNOW WILL PILE
UP QUICKLY AT THESE HIGHER LOCATIONS. HAVE KEPT A CLOSE EYE ON THE
MOISTURE FIELDS OVER THE LAST FEW DAYS AND HAVE SEEN THE FORECAST
MODELS INCREASE MOISTURE FROM THE SOUTH AND NOW INCREASE MOISTURE
ACROSS WESTERN CO AND EASTERN UT AS IT WRAPS AROUND THE SLOWLY
PROGRESSING CLOSED LOW. THE SLOW MOVEMENT AND DYNAMICS OF THE LOW
SHOULD BE EFFECTIVE IN OVERCOMING THE MOUNTAIN SHADOW EFFECT. SPEC
HUMIDITY VALUES ARE NOW BEING PROGGED TO REACH AND EXCEED 4 G/KG
WHICH IS RATHER SIGNIFICANT WITH SUCH A COLD SYSTEM IN APRIL. SNOW
LEVEL IS DEFINITELY A CHALLENGE AND AM EXPECTING NORTHERN COLORADO
VALLEYS TO SEE MAINLY RAIN AND A RAIN/SNOW MIX WITH LITTLE
ACCUMULATION. AN UPTICK IN ACTIVITY IS EXPECTED THIS AFTERNOON AND
EVENING...BUT ALL FORECAST MODELS REALLY PICK UP COVERAGE IN
ACTIVITY FRIDAY AFTERNOON. CONDITIONS NORTH OF I-70 TODAY WILL BE
BREEZY AND WET MUCH OF TODAY. ELSEWHERE WILL RECEIVE SCATTERED
SHOWERS WITH THE EXCEPTION OF THE CENTRAL MOUNTAINS WHICH WILL SEE
DETERIORATING CONDITIONS TODAY.
ADDED NORTHERN SAN JUANS TO A WINTER STORM WATCH STARTING TONIGHT
AS WE ANTICIPATE FLOW CHANGING TO WEST NORTHWESTERLY. STRONG
NORTHERLY FLOW FRIDAY EVENING WILL ALSO BE FAVORABLE FOR THIS AREA
TO RECEIVE HEAVY SNOW IF THE LOW STAYS ON TRACK. CONFIDENCE IS
MODERATE ON CURRENT SOLUTIONS EVEN A COUPLE DAYS OUT DUE TO THE
LOW TRACKING SO SLOWLY ACROSS THE REGION.
.LONG TERM...(FRIDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 416 AM MDT THU APR 16 2015
MEANDERING LOW WILL CONTINUE TO WREAK HAVOC ON THE FORECAST AS WE
START OFF THIS EXTENDED PERIOD. DEEP NORTHERLY FLOW ON THE BACK
SIDE OF THE...EXPECTED TO BE EXITING LOW PRESSURE SYSTEM...MAY
KEEP LOCALLY HEAVY SNOW FALLING ACROSS THE NORTHWEST SAN JUAN
MOUNTAINS AND OTHER FAVORED NORTH FACING SLOPES IN WESTERN
COLORADO. THIS SYSTEM LOOKS TO LINGER OVER THE AREA UNTIL MIDDAY
SATURDAY...BEFORE A KICKING WAVE DROPS INTO MONTANA LATE SATURDAY
AFTERNOON AND EVENING. THIS SYSTEM SHOULD KICK THE LOW OUT INTO
THE PLAINS WITH SOMEWHAT MOIST NW FLOW HOLDING IN PLACE THROUGH
THE REMAINDER OF THE WEEKEND. SO EXPECT UNSETTLED CONDITIONS TO
CONTINUE OVER THE NORTHERN AND CENTRAL MOUNTAINS WITH ADDITIONAL
LATE SEASON SNOWFALL ANTICIPATED...ESPECIALLY ABOVE THE 9K LEVEL.
SLIGHT INCREASE IN HEIGHTS EXPECTED AS WE MOVE INTO THE NEW WORK
WEEK...WHICH WILL MODIFY TEMPS UP A BIT. HOWEVER...ENOUGH PACIFIC
MOISTURE STREAMING INTO THE REGION TO KEEP ISOLATED TO SCATTERED
POPS ROLLING THROUGHOUT THE PERIOD...GENERALLY FOCUSED ON THE
HIGHER TERRAIN. ANOTHER STRONG CLOSED LOW BEING ADVERTISED BY BOTH
THE GFS AND ECMWF LATE NEXT WEEK PROMISES TO BRING MORE WIDESPREAD
PRECIPITATION TO THE REGION AS WE CLOSE THE WEEK OUT. EXPECT
TEMPS TO BE RUNNING NEAR TO SLIGHTLY BELOW NORMAL THROUGH THIS
PERIOD.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z FRIDAY MORNING)
ISSUED AT 416 AM MDT THU APR 16 2015
A STRONG LOW PRESSURE SYSTEM WILL BE DROPPING SOUTH INTO THE FOUR
CORNERS AREA TODAY AND WILL MEANDER SLOWLY ENE ACROSS COLORADO FOR
THE NEXT 24 HOURS. EXPECT WIDESPREAD SHOWERS TO DEVELOP ACROSS THE
REGION BY THIS AFTERNOON...WITH LOCALLY HEAVY SNOW EXPECTED OVER
THE MOUNTAINS THROUGH SATURDAY. CIGS WILL BE DROPPING THROUGHOUT
THE REGION WITH AREAS OF MVFR AND IFR CONDS ANTICIPATED LATER
TONIGHT. MOUNTAINS WILL BECOME OBSCURED...ESPECIALLY NEAR SHOWERS.
GUSTY EASTERLY WINDS CAN BE EXPECTED ACROSS WESTERN COLORADO AND
EASTERN UTAH THROUGH FRIDAY MORNING.
&&
.GJT WATCHES/WARNINGS/ADVISORIES...
CO...WINTER WEATHER ADVISORY UNTIL NOON MDT SATURDAY FOR COZ004-009-
013.
WINTER STORM WARNING UNTIL NOON MDT SATURDAY FOR COZ010-012.
WINTER STORM WATCH FROM LATE TONIGHT THROUGH SATURDAY MORNING
FOR COZ018.
FREEZE WATCH FROM LATE TONIGHT THROUGH FRIDAY MORNING FOR COZ021.
UT...WINTER STORM WARNING UNTIL 6 AM MDT SATURDAY FOR UTZ023.
&&
$$
UPDATE...JAD
SHORT TERM...JAM
LONG TERM...JDC
AVIATION...JDC
AREA FORECAST DISCUSSION
NWS NEW ORLEANS LA
832 AM CDT THU APR 16 2015
...SOUNDING DISCUSSION...
THE ATMOSPHERE CONTINUES TO REMAIN MOISTURE-LADEN WITH
PRECIPITABLE WATER VALUES REMAINING WELL ABOVE NORMAL. THAT LINE
WILL CONTINUE TO BE REPEATED THROUGH THE REST OF THE WEEK AND
INTO THE WEEKEND. FORECAST CAPE VALUES WILL APPROACH 1500 J/KG AND
LI WILL DROP TO -4 LATER TODAY. FREEZING LEVEL IS AROUND
12700 FEET...WHICH IS SIMILAR TO LAST EVENING. HOWEVER...WET BULB
ZERO HEIGHT IS ABOUT 1000 FEET HIGHER THAN LAST NIGHT. THERE IS
SOME DRY AIR SHOWN IN THE SOUNDING AROUND 17000 FEET THAT WOULD
SUPPORT A DAMAGING WIND GUST POTENTIAL. MAIN FOCUS FOR TODAY WILL
BE THREAT FOR HEAVY RAINFALL. THERE IS SOME DIRECTIONAL AND SPEED
SHEAR...BUT STORM RELATIVE HELICITY VALUES ARE LOW SO TORNADO
THREAT IS ALSO QUITE LOW. WINDS WERE FROM THE SOUTHEAST AT THE
SURFACE AND THEN ROTATED AROUND TO THE WEST BY THE MIDLEVELS. A
29 KNOT WIND WAS OBSERVED AT 500MB AND A PEAK WIND SPEED OF 93
KNOTS WAS FOUND AT 38400 FEET/217MB.
12Z BALLOON INFO: NO ISSUES WITH THE FLIGHT THIS MORNING THAT
LASTED 105 MINUTES. THE BALLOON REACHED A HEIGHT OF 21 MILES
ABOVE THE GROUND AND WENT 53 MILES DOWNRANGE BURSTING EAST OF
MCHENRY.
ANSORGE
&&
.PREV DISCUSSION... /ISSUED 414 AM CDT THU APR 16 2015/
SHORT TERM...
LITTLE CHANGE IN THINKING FROM THE PREVIOUS FORECAST...AS THE AREA
REMAINS UNDER THE INFLUENCE OF A BROAD REGION OF ENHANCED OMEGA
THROUGH SATURDAY AS A SLOW MOVING UPPER LEVEL TROUGH OVER THE FOUR
CORNERS DRIFTS THROUGH THE SOUTHERN PLAINS AND LOWER MISSISSIPPI
VALLEY. SEVERAL ROUNDS OF SHOWERS AND THUNDERSTORMS ASSOCIATED
WITH PULSES UP INCREASED VORTICITY EJECTING OUT OF THE BASE OF THE
PARENT UPPER LEVEL LOW WILL IMPACT THE REGION THROUGH THIS
PERIOD...WITH THE RISK OF HEAVY RAINFALL AND LOCALLY SEVERE
THUNDERSTORMS EACH DAY. HOWEVER... THE RISK OF SEVERE
THUNDERSTORM DEVELOPMENT WILL BE GREATEST ON FRIDAY AND SATURDAY
AS OVERALL LAPSE RATES AND SHEAR PROFILES LOOK MORE FAVORABLE ON
THESE DAYS. THERE WILL BE A THREAT OF HEAVY RAINFALL THREAT EVERY
DAY AS PW VALUES REMAIN ELEVATED AT AROUND 1.75 INCHES AND THE
ATMOSPHERE REMAINS MOISTURE LOADED. GIVEN THIS THREAT...THE FLASH
FLOOD WATCH REMAINS IN EFFECT THROUGH FRIDAY EVENING. THE WATCH
MAY NEED TO BE EXTENDED INTO SATURDAY LATER TODAY.
FOR TODAY...AFTER REVIEWING THE GFSBUFR SOUNDINGS AND LOOKING AT
THE LATEST HRRR OUTPUT...EXPECT TO SEE CONVECTION INITIALLY IMPACT
AREAS AROUND BATON ROUGE THIS MORNING AND THEN SPREAD SOUTH AND
EAST INTO NEW ORLEANS AND THE MISSISSIPPI GULF COAST DURING THE
AFTERNOON AND EVENING HOURS. SOUNDING PROFILES ARE NOT AS
SUPPORTIVE OF SEVERE THUNDERSTORMS TODAY...AS MID-LEVEL LAPSE
RATES ARE CLOSER TO MOIST ADIABATIC AND THE WET BULB ZERO HEIGHT
REMAINS AROUND 13K FEET. ADDITIONALLY...THERE IS VERY LITTLE WIND SHEAR
NOTED OVER THE AREA. SPC HAS ONLY A MARGINAL RISK OF SEVERE
THUNDERSTORM DEVELOPMENT TODAY GIVEN THESE WEAKER PARAMETERS.
THE SOUNDING IS SUPPORTIVE OF LOCALLY HEAVY RAINFALL DEVELOPING
TODAY. THERE IS LITTLE IN THE WAY OF CONVECTIVE INHIBITION...SO IT
WILL NOT TAKE MUCH TO GET THUNDERSTORMS GOING. THESE THUNDERSTORMS
WILL HAVE A VERY EFFICIENT RAIN PROCESS...WHICH WILL ALLOW FOR
RAINFALL RATES OF UP TO 2 INCHES PER HOUR AT TIMES. THUS...SOME
LOCALIZED FLOODING WILL BE THREAT TODAY.
HEADING INTO TONIGHT...MUCH AS SEEN THE LAST FEW NIGHTS...THE
THUNDERSTORM ACTIVITY WILL QUICKLY DIMINISH AS DAYTIME HEATING
GIVES WAY. THERE WILL BE A RISK OF SOME SCATTERED SHOWERS AND B
THUNDERSTORMS DEVELOPING DURING THE NIGHT...BUT OVERALL COVERAGE
WILL BE MUCH LOWER THAN DURING THE PEAK HEATING HOURS.
TEMPERATURES WILL ONCE AGAIN COOL BACK INTO THE MIDDLE TO UPPER
60S...AND SOME PATCHY FOG WILL DEVELOP TOWARD DAYBREAK DUE TO THE
WET GROUND CONDITIONS AND A WEAK LOW LEVEL INVERSION CUTTING OFF
THE BOUNDARY LAYER WINDS. FOG COVERAGE LOOKS TO BE LOW ENOUGH TO
KEEP OUT OF THE OFFICIAL FORECAST FOR NOW.
FRIDAY LOOKS TO BE A VERY ACTIVE DAY ACROSS THE REGION. GFSBUFR
SOUNDINGS SHOW A MUCH MORE FAVORABLE ENVIRONMENT FOR SEVERE
THUNDERSTORM DEVELOPMENT...ESPECIALLY FROM LATE MORNING ON. MID-
LEVEL LAPSE RATES WILL INCREASE DRAMATICALLY FRIDAY
AFTERNOON...SHOOTING UP TO 7 C/KM BETWEEN 700 AND 500 MB. THESE
HIGH LAPSE RATES WILL ALSO BE ABOVE THE FREEZING LEVEL WHICH WILL
FALL BELOW 13K FEET. ADDITIONALLY...WET BULB ZERO HEIGHTS WILL
DROP TO AROUND 11K FEET. WITH STRONG LAPSE RATES IN THE HAIL
GROWTH ZONE...SOME LARGE HAIL WILL ONCE AGAIN BE POSSIBLE ON
FRIDAY. LOOKING AT THE WIND PROFILE...OVERALL HELICITY VALUES WILL
BE FAIRLY WEAK ON FRIDAY...BUT WITH SOME DRY AIR ADVECTING INTO
THE MID-LEVELS...THE THREAT OF STRAIGHT LINE WINDS AND BOWING
SEGMENTS INCREASES. THERE IS ENOUGH LOW LEVEL HELICITY...THAT AN
ISOLATED TORNADO COULD NOT BE RULED OUT FRIDAY AFTERNOON.
OVERALL...EXPECT THE MAIN THREAT TO BE HAIL AND STRAIGHT LINE
WINDS ON FRIDAY. CONDITIONS WILL ONCE AGAIN IMPROVE DURING THE
EVENING HOURS ON FRIDAY AS THE VORT MAX SLIDES TO THE EAST AND THE
ATMOSPHERE STABILIZES A BIT.
HOWEVER...THE PARENT UPPER LEVEL TROUGH WILL BEGIN TO DIRECTLY
IMPACT THE REGION ON SATURDAY AS IT MOVES THROUGH THE SOUTHERN
PLAINS. SATURDAY LOOKS TO HAVE THE HIGHEST THREAT OF BOTH HEAVY
RAINFALL AND SEVERE THUNDERSTORMS. PW VALUES WILL BE VERY
HIGH...APPROACHING 2 INCHES...AND THE OVERALL LAPSE RATES WILL
TURN MORE MOIST ADIABATIC THROUGH THE DAY. THIS WILL DECREASE THE
HAIL THREAT SUBSTANTIALLY...WITH WET BULB ZERO HEIGHTS REMAINING
WELL ABOVE 13K FEET. HOWEVER...VERY EFFICIENT RAINFALL PROCESSES
WILL DEVELOP...RESULTING IN HOURLY RAINFALL RATE POTENTIAL OF 2 TO
3 INCHES IF A STORM STALLS OVER THE SAME AREA. FORTUNATELY...THE
STORMS WILL BE FAST MOVING...SO ACTUAL RAINFALL RATES WILL BE
LOWER. THESE STRONG WINDS WILL UNFORTUNATELY MEAN THAT THE RISK OF
STRAIGHT LINE WINDS AND TORNADOES WILL BE HIGH ON SATURDAY. 0-3KM
SHEAR WILL INCREASE TO AROUND 35 KNOTS AND STORM RELATIVE HELICITY
VALUES WILL RISE TO AROUND 250 M2/S2 SATURDAY AFTERNOON. THESE
VALUES ARE VERY CONDUCIVE TO ROTATING THUNDERSTORM
DEVELOPMENT...AND THUS THE FORMATION OF TORNADOES. A FRONTAL
BOUNDARY WILL PUSH THROUGH THE AREA SATURDAY NIGHT...WHICH WILL
KEEP THE RISK OF SHOWERS AND THUNDERSTORMS IN PLACE THROUGH THE
NIGHT...AND HAVE LIKELY POPS IN PLACE TO REFLECT THIS.
LONG TERM...
CONDITIONS WILL BEGIN TO IMPROVE ON SUNDAY...AS A COLD FRONT
PUSHES OFFSHORE AND RAIN CHANCES SHOULD DECREASE THROUGH THE DAY
FROM WEST TO EAST. THE PARENT UPPER LEVEL TROUGH AXIS WILL FINALLY
PUSH THROUGH THE REGION SUNDAY NIGHT...WITH INCREASING NEGATIVE
VORTICITY ADVECTION AND SUBSIDENCE TAKING HOLD OF THE AREA FOR
MONDAY. AT MOST...THERE COULD BE SOME LINGERING SHOWERS AND CLOUDS
ALONG THE IMMEDIATE COAST MONDAY MORNING...WITH CLEARING
CONDITIONS EXPECTED BY MONDAY AFTERNOON. AS A MORE ZONAL FLOW
REGIME TAKES HOLD ALOFT...AND SOME DRIER MID-LEVEL AIR LINGERS
OVER THE AREA SKIES SHOULD REMAIN PARTLY CLOUDY AND RAIN CHANCES
WILL BE LESS THAN 10 PERCENT FOR TUESDAY. TEMPERATURES WILL REMAIN
NEAR NORMAL...WITH HIGHS IN THE LOWER 80S AND LOWS IN THE UPPER
50S AND LOWER 60S.
UNFORTUNATELY...A WEAK IMPULSE RIDING ALONG THE ZONAL FLOW WILL
SLIDE THROUGH THE AREA ON WEDNESDAY. THE SYSTEM WILL BE FAIRLY
WEAK...BUT ENOUGH FORCING AND MOISTURE WILL BE IN PLACE TO SPARK
OFF SOME SCATTERED SHOWERS AND THUNDERSTORMS DURING THE DAY ON
WEDNESDAY. RAIN CHANCES WILL BE HIGHEST ALONG THE COAST AND
OFFSHORE WHERE OVERALL MOISTURE AND FORCING IS EXPECTED TO BE
GREATEST. AS THIS FEATURE PULLS TO THE EAST WEDNESDAY...SKIES
SHOULD CLEAR AND RAIN CHANCES WILL DROP. HOWEVER...ANOTHER IMPULSE
WILL SLIDE THROUGH ON THURSDAY...BRINGING ANOTHER CHANCE OF
ISOLATED SHOWERS AND THUNDERSTORMS FOR THURSDAY.
AVIATION...
TAFS WILL BE DEPENDENT ONCE AGAIN ON EVENTUAL CONVECTIVE DEVELOPMENTS TODAY.
CONVECTIVE BASED MODELS SUGGEST ONSET OF STORMS COULD IMPACT SOME LOCATIONS
BY 14Z...PRIMARILY WESTERNMOST LOCATIONS LIKE KBTR AND KHUM...THOUGH ALL
TERMINALS SHOULD SEE SOME PERIODS OF TSRA/SHRA THROUGHOUT THE DAY. DOWN BURST
POTENTIAL WILL BE HIGH TODAY WITH GUST POTENTIAL 35-45 KT. EFFICIENT RAINFALL
PROCESS SHOULD ALSO LOWER VSBY TO VLIFR LEVELS AT TIMES DURING HEAVY RAINFALL.
OTHERWISE...VFR CONDITIONS SHOULD PREVAIL AFTER 16Z OUTSIDE
CONVECTION.
MARINE...
AN INTERESTING WAKE LOW PHENOMENA IMPACTED THE OFFSHORE WATERS
THIS MORNING...BUT THIS HAS SINCE WEAKENED. OVERALL...EXPECT TO
SEE AN ONSHORE FLOW OF 10 TO 15 KNOTS REMAIN OVER THE COASTAL
WATERS THROUGH FRIDAY. AS AN UPPER LEVEL LOW AND ASSOCIATED WEAK
SURFACE LOW AND FRONT MOVE THROUGH OVER THE WEEKEND...WINDS WILL
INCREASE INTO EXERCISE CAUTION RANGE SATURDAY AND REMAIN ELEVATED
INTO SUNDAY. SEAS WILL RESPOND AND INCREASE TO 3 TO 5 FEET IN THE
OFFSHORE WATERS. THE GRADIENT WILL EASE OVER THE AREA ON
MONDAY...ALLOWING FOR WEAKER AND MORE VARIABLE FLOW OF 10 KNOTS OR
LESS. SEAS WILL ALSO FALL BACK INTO THE 1 TO 3 FEET RANGE FOR
MONDAY AND TUESDAY.
DECISION SUPPORT...
DSS CODE...BLUE.
DEPLOYED...NONE.
ACTIVATION...NONE.
ACTIVITIES...MONITORING HEAVY RAINFALL/FLOODING POTENTIAL
ASSESSING SEVERE WEATHER THREAT THRU WEEKEND.
DECISION SUPPORT SERVICES (DSS) CODE LEGEND
GREEN = NO WEATHER IMPACTS THAT REQUIRE ACTION
BLUE = LONG FUSED WATCH/WARNING/ADVISORY IN EFFECT OR HIGH
VISIBILITY EVENT
YELLOW = HEIGHTENED IMPACTS WITH SHORT FUSED
WATCH/WARNING/ADVISORY ISSUANCES; RADAR SUPPORT
ORANGE = HIGH IMPACTS - SLIGHT TO MODERATE RISK SEVERE; NEARBY
TROPICAL EVENTS; HAZMAT OR OTHER LARGE EPISODES
RED = FULL ENGAGEMENT FOR MODERATE TONIGHT RISK SVR
AND/OR DIRECT TROPICAL THREATS; EVENTS OF NATIONAL
SIGNIFICANCE
&&
.PRELIMINARY POINT TEMPS/POPS...
MCB 78 65 79 66 / 80 60 70 50
BTR 79 66 81 67 / 80 60 70 50
ASD 78 67 80 68 / 70 70 70 60
MSY 78 69 80 69 / 70 70 70 60
GPT 77 68 78 69 / 70 70 70 70
PQL 78 67 79 69 / 70 70 70 70
&&
.LIX WATCHES/WARNINGS/ADVISORIES...
LA...FLASH FLOOD WATCH THROUGH FRIDAY EVENING FOR LAZ040-046>050-
056>070-072.
GM...NONE.
MS...FLASH FLOOD WATCH THROUGH FRIDAY EVENING FOR MSZ077-080>082.
GM...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS PITTSBURGH PA
1020 AM EDT THU APR 16 2015
.SYNOPSIS...
A WEAK UPPER LEVEL DISTURBANCE AND TRAILING COLD FRONT WILL BRING
SHOWERS THIS AFTERNOON INTO FRIDAY MORNING. HIGH PRESSURE WILL
BRING A DRY START TO THE WEEKEND.
&&
.NEAR TERM /THROUGH TONIGHT/...
ONLY CHANGES WERE TO MAX TEMPS AND HOURLY TEMPS. WHERE SHOWERS
HAVE ARRIVED TEMPERATURES HAVE DROPPED OFF DUE TO WET
BULBING...WHILE AREAS NORTH AND EAST OF KPIT I-80 REMAIN WARMER
WITH SOME SUNSHINE.
PREVIOUS...
SHOWER CHANCES WILL INCREASE FROM WEST TO EAST AHEAD OF A
SHORTWAVE TROUGH THAT REACHES THE AREA LATE THIS AFTERNOON. THINK
A SLOWER APPROACH TO BEGINNING THE SHOWERS IS THE WAY TO GO AS THE
MOISTURE ASSOCIATED WITH THE UPPER LEVEL WAVE WILL BE RUNNING INTO
A VERY DRY ATMOSPHERE. SHOWERS WILL OVERSPREAD THE ENTIRE AREA
THIS AFTERNOON AS THE WAVE MOVES THROUGH.
WITH THE CLOUDS AND SHOWERS...TEMPERATURES WILL BE A BIT BELOW
SEASONABLE LEVELS. SHOWERS CONTINUE OVERNIGHT AND INTO FRIDAY
MORNING AS THE SURFACE BOUNDARY SLOWLY MOVES THROUGH THE REGION.
&&
.SHORT TERM /FRIDAY THROUGH SATURDAY/...
UPPER LEVEL SUPPORT WILL QUICKLY EXIT THE AREA...SO EXPECT THE
SHOWERS TO RAP UP IN THE EAST FRIDAY MORNING. NO REAL DISCERNIBLE
COLD ADVECTION IS EXPECTED...SO TEMPERATURES WILL BE ABLE TO
REBOUND BACK TO...IF NOT WARMER THAN SEASONAL AVERAGES FRIDAY
AFTERNOON.
BROAD SURFACE HIGH AND UPPER LEVEL RIDGE WILL BUILD INTO THE OHIO
VALLEY SATURDAY.
&&
.LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/...
MODELS STILL SHOWING A LARGE AND SLOW MOVING SYSTEM THAT WILL
BRING AN EXTENDED PERIOD OF SHOWERS BEGINNING SUNDAY AND
CONTINUING INTO EARLY TUESDAY. DRY AND SEASONABLE WEATHER WILL
RETURN BEHIND THIS SYSTEM.
&&
.AVIATION /14Z THURSDAY THROUGH MONDAY/...
VFR CONDITIONS WILL VERY SLOWLY GIVE WAY TO LOCAL MVFR CONDITIONS
IN SCATTERED SHOWERS AS THEY ENCROACH ON THE REGION ESPECIALLY
THIS AFTERNOON. CONFIDENCE IS LOW ON THE TIMES OF THE LOW
DETERIORATION OF CIGS...HOWEVER VIRGA SHOULD GRADUALLY TURN INTO
LIGHT RAIN AS HIGHER DEWPOINTS ENCROACH. INCREASING ESE TURNING
SOUTH WINDS SHOULD PRECLUDE VISIBLITY RESTRICTIONS...HOWEVER CIGS
WILL TREND AT LEAST CLOSE TO IFR BY TONIGHT AS DEEPER MOISTURE
SLOWLY ENTERS THE REGION.FRIES
.OUTLOOK.../TUESDAY NIGHT THROUGH SUNDAY/...
THE NEXT CHANCE FOR GENERAL RESTRICTIONS IS EXPECTED WITH THE
APPROACH OF LOW PRESSURE ON SUNDAY.
&&
.PBZ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
OH...NONE.
PA...NONE.
WV...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS PITTSBURGH PA
752 AM EDT THU APR 16 2015
.SYNOPSIS...
A WEAK UPPER LEVEL DISTURBANCE AND TRAILING COLD FRONT WILL BRING
SHOWERS TODAY THROUGH FRIDAY MORNING. A DRY AND COMFORTABLE START
TO THE WEEKEND.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
NO CHANGES NEEDED TO EARLY MORNING UPDATE
PREVIOUS...
SHOWER CHANCES WILL INCREASE FROM WEST TO EAST THIS MORNING AHEAD
OF A SHORTWAVE TROUGH THAT REACHES THE AREA LATE THIS AFTERNOON.
THINK A SLOWER APPROACH TO BEGINNING THE SHOWERS IS THE WAY TO GO AS
THE MOISTURE ASSOCIATED WITH THE UPPER LEVEL WAVE WILL BE RUNNING
INTO A VERY DRY ATMOSPHERE. SHOWERS WILL OVERSPREAD THE ENTIRE
AREA THIS AFTERNOON AS THE WAVE MOVES THROUGH.
WITH THE CLOUDS AND SHOWERS...TEMPERATURES WILL BE A BIT BELOW
SEASONABLE LEVELS.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH SATURDAY/...
SHOWERS CONTINUE OVERNIGHT AND INTO FRIDAY MORNING AS THE SURFACE
BOUNDARY SLOWLY MOVES THROUGH THE REGION. UPPER LEVEL SUPPORT
WILL QUICKLY EXIT THE AREA...SO EXPECT THE SHOWERS TO RAP UP IN
THE EAST FRIDAY MORNING. NO REAL DISCERNIBLE COLD ADVECTION IS
EXPECTED...SO TEMPERATURES WILL BE ABLE TO REBOUND BACK TO...IF
NOT WARMER THAN SEASONAL AVERAGES FRIDAY AFTERNOON.
BROAD SURFACE HIGH AND UPPER LEVEL RIDGE WILL BUILD INTO THE OHIO
VALLEY SATURDAY.
&&
.LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/...
MODELS STILL SHOWING A LARGE AND SLOW MOVING SYSTEM THAT WILL
BRING AN EXTENDED PERIOD OF SHOWERS BEGINNING SUNDAY AND
CONTINUING INTO EARLY TUESDAY. DRY AND SEASONABLE WEATHER WILL
RETURN BEHIND THIS SYSTEM.
&&
.AVIATION /12Z THURSDAY THROUGH MONDAY/...
VFR CONDITIONS WILL VERY SLOWLY GIVE WAY TO LOCAL MVFR CONDITIONS
IN SCATTERED SHOWERS AS THEY ENCROACH ON THE REGION ESPECIALLY
THIS AFTERNOON. CONFIDENCE IS LOW ON THE TIMES OF THE LOW
DETERIORATION OF CIGS...HOWEVER VIRGA SHOULD GRADUALLY TURN INTO
LIGHT RAIN AS HIGHER DEWPOINTS ENCROACH. INCREASING ESE TURNING
SOUTH WINDS SHOULD PRECLUDE VISIBLITY RESTRICTIONS...HOWEVER CIGS
WILL TREND AT LEAST CLOSE TO IFR BY TONIGHT AS DEEPER MOISTURE
SLOWLY ENTERS THE REGION.FRIES
.OUTLOOK.../TUESDAY NIGHT THROUGH SUNDAY/...
THE NEXT CHANCE FOR GENERAL RESTRICTIONS IS EXPECTED WITH THE
APPROACH OF LOW PRESSURE ON SUNDAY.
&&
.PBZ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
OH...NONE.
PA...NONE.
WV...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS PITTSBURGH PA
620 AM EDT THU APR 16 2015
.SYNOPSIS...
A WEAK UPPER LEVEL DISTURBANCE AND TRAILING COLD FRONT WILL BRING
SHOWERS TODAY THROUGH FRIDAY MORNING. A DRY AND COMFORTABLE START
TO THE WEEKEND.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
SHOWER CHANCES WILL INCREASE FROM WEST TO EAST THIS MORNING AHEAD
OF A SHORTWAVE TROUGH THAT REACHES THE AREA LATE THIS AFTERNOON.
STILL SEEING SOME TIMING DIFFERENCES IN MODEL SOLUTIONS AS THE
MOISTURE ASSOCIATED WITH THE UPPER LEVEL WAVE WILL BE RUNNING INTO
A VERY DRY ATMOSPHERE. THINK A SLOWER APPROACH TO BEGINNING THE
SHOWERS IS THE WAY TO GO. SHOWERS WILL OVERSPREAD THE ENTIRE AREA
THIS AFTERNOON AS THE WAVE MOVES THROUGH.
WITH THE CLOUDS AND SHOWERS...TEMPERATURES WILL BE A BIT BELOW
SEASONABLE LEVELS.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH SATURDAY/...
SHOWERS CONTINUE OVERNIGHT AND INTO FRIDAY MORNING AS THE SURFACE
BOUNDARY SLOWLY MOVES THROUGH THE REGION. UPPER LEVEL SUPPORT
WILL QUICKLY EXIT THE AREA...SO EXPECT THE SHOWERS TO RAP UP IN
THE EAST FRIDAY MORNING. NO REAL DISCERNIBLE COLD ADVECTION IS
EXPECTED...SO TEMPERATURES WILL BE ABLE TO REBOUND BACK TO...IF
NOT WARMER THAN SEASONAL AVERAGES FRIDAY AFTERNOON.
BROAD SURFACE HIGH AND UPPER LEVEL RIDGE WILL BUILD INTO THE OHIO
VALLEY SATURDAY.
&&
.LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/...
MODELS STILL SHOWING A LARGE AND SLOW MOVING SYSTEM THAT WILL
BRING AN EXTENDED PERIOD OF SHOWERS BEGINNING SUNDAY AND
CONTINUING INTO EARLY TUESDAY. DRY AND SEASONABLE WEATHER WILL
RETURN BEHIND THIS SYSTEM.
&&
.AVIATION /10Z THURSDAY THROUGH MONDAY/...
VFR CONDITIONS WILL VERY SLOWLY GIVE WAY TO LOCAL MVFR CONDITIONS
IN SCATTERED SHOWERS AS THEY ENCROACH ON THE REGION ESPECIALLY
THIS AFTERNOON. CONFIDENCE IS LOW ON THE TIMES OF THE LOW
DETERIORATION OF CIGS...HOWEVER VIRGA SHOULD GRADUALLY TURN INTO
LIGHT RAIN AS HIGHER DEWPOINTS ENCROACH. INCREASING ESE TURNING
SOUTH WINDS SHOULD PRECLUDE VISIBLITY RESTRICTIONS...HOWEVER CIGS
WILL TREND AT LEAST CLOSE TO IFR BY TONIGHT AS DEEPER MOSITURE
SLOWLY ENTERS THE REGION. FRIES
.OUTLOOK.../TUESDAY NIGHT THROUGH SUNDAY/...
THE NEXT CHANCE FOR GENERAL RESTRICTIONS IS EXPECTED WITH THE
APPROACH OF LOW PRESSURE ON SUNDAY.
&&
.PBZ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
OH...NONE.
PA...NONE.
WV...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS GRAND RAPIDS MI
1123 AM EDT THU APR 16 2015
LATEST UPDATE...
HYDRO
.SYNOPSIS...
ISSUED AT 310 AM EDT THU APR 16 2015
LIGHT RAIN IS LIKELY TODAY ACROSS MUCH OF SOUTHWEST LOWER MICHIGAN
AS WEAK LOW PRESSURE MOVES NORTH FROM THE GULF. THE SHOWERS WILL
DIMINISH TONIGHT LEADING TO A DRY FRIDAY AND SATURDAY. RAIN IS BACK
IN THE PICTURE LATE IN THE WEEKEND AND EARLY NEXT WEEK AS A STRONGER
LOW MOVES EAST FROM THE PLAINS ACROSS THE GREAT LAKES.
TODAY WILL BE A BIT COOLER THAN WEDNESDAY; WE/LL SEE HIGHS IN THE
50S. TEMPERATURES WILL CLIMB TO AROUND 70 FRIDAY AND SATURDAY BEFORE
COOLER WEATHER DEVELOPS EARLY NEXT WEEK. MUCH OF NEXT WEEK WILL SEE
HIGHS ONLY AROUND 50.
&&
.UPDATE...
ISSUED AT 856 AM EDT THU APR 16 2015
I DID A QUICK UPDATE TO THE POP AND WEATHER GRIDS TO BETTER
REFLECT THE CURRENT RADAR TRENDS. THAT MEANS I INCREASED THE POP
TO NEAR 100 PCT OVER OUR NW CWA AND I HAVE AN AREA OF LOW POP
SOUTHWEST OF GRR (IT IS REALLY THERE) THAT MOVES NORTH WITH TIME.
THE ENTIRE AREA OF SHOWERS SHOULD BE MOSTLY OUT OF OUR CWA BY
MID AFTERNOON AS DRIER AIR MOVES IN AT MID LEVELS. THIS IDEA IS
MOSTLY BASED ON USING THE RAP MODEL LIFT IN THE DGZ WHERE THE AIR
IN THAT LAYER IS SATURATED. AT 8 AM THE AREA OF BEST LIFT IS NEAR
AND WEST OF US-131. BY 2 PM IT IS MOSTLY EAST OF I-75 BUT THERE IS
A SMALL AREA OF STRONG LIFT JUST SOUTH OF GRR AT THAT TIME WHICH
LIFTS TO NEAR LANSING BY 5 PM. THAT WILL HAVE TO BE WATCHED TO SEE
OF AN AREA OF SIGNIFICANT SHOWERS DOES DEVELOP THERE. I STILL EXPECT
NO THUNDERSTORM ACTIVITY TODAY.
&&
.SHORT TERM...(TODAY THROUGH SATURDAY)
ISSUED AT 310 AM EDT THU APR 16 2015
FORECAST CONCERNS DEAL WITH PCPN TRENDS TODAY. OVERALL...THE
FORECAST IS LARGELY ON TRACK ALTHOUGH QPF HAS BEEN TRIMMED A BIT.
00Z SOUNDING AT DTX WAS EXTREMELY DRY BELOW 450 MB AND EXPLAINS WHY
WE HAVEN/T SEEN MUCH RAIN AT THE SFC DESPITE ECHOS ACROSS THE LAKE
SHORE. THE SFC WAVE OF LOW PRESSURE TO THE SOUTH WILL MOVE OVER THE
CWA TODAY AND WE SHOULD SEE THE LOWER LEVELS OF THE ATM MOISTEN AND
RAIN TO DEVELOP. KGRR-88D SHOWS ECHO INTENSITY INCREASING A BIT AS
PCPN CONTINUES TO MOVE NORTH FROM INDIANA. SHORT RANGE NWP SHOWED
THE AREA OF THETA-E DECREASING WITH HEIGHT REMAINING SOUTH OF THE
CWA SO WE OPTED TO GO WITH NO THUNDER IN THE GRIDS TODAY. PCPN WILL
BEGIN TO MOVE EAST THIS AFTERNOON AND END EARLY IN THE EVENING. THIS
WILL LEAD TO A COUPLE OF DRY DAYS FRIDAY AND SATURDAY AS HIGH
PRESSURE NOSES IN FROM ONTARIO.
TEMPS WILL BE HELD DOWN A BIT BY THE SHOWERS TODAY AND WE`LL GO WITH
HIGHS IN THE MID TO UPPER 50S. UPPER HEIGHT RISES ASSOCIATED WITH
THE RIDGE WILL RESULT IN TEMPS AROUND 10 DEGREES WARMER FRIDAY AND
SATURDAY.
.LONG TERM...(SATURDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 310 AM EDT THU APR 16 2015
MODEL GUIDANCE REMAINS CONSISTENT IN SHOWING RAIN MOVING IN ON
SUNDAY WITH THE BEST CHANCE FOR WET WEATHER SUNDAY AFTERNOON AND
EVENING AS A SFC LOW AND UPPER TROUGH AXIS MOVES OVER LOWER
MICHIGAN. THE LOW CUTS OFF AND BECOMES VERTICALLY STACKED NORTH OF
LAKE SUPERIOR ON MONDAY WITH VORT ENERGY ROTATING THROUGH LOWER
MICHIGAN ON TUESDAY AND WEDNESDAY. GIVEN WET BULB ZERO HEIGHTS
CRASHING TO NEAR THE SFC...DO NOT BE SURPRISED TO SEE SOME SNOW
ACROSS AT LEAST THE NORTHERN ZONES TUESDAY THROUGH WEDNESDAY.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z FRIDAY MORNING)
ISSUED AT 736 AM EDT THU APR 16 2015
MVFR CONDITIONS WILL BECOME MORE WIDESPREAD TODAY AS SCATTERED SHOWERS
CONTINUE BUT THERE SHOULD FEW IF ANY AREAS OF IFR THROUGH TONIGHT.
WINDS WILL BE SOUTHEAST TODAY AOB 10 KNOTS THEN GO WEST BY THIS
EVENING AND DECREASE TO ABOUT 5 KNOTS.
&&
.MARINE...
ISSUED AT 310 AM EDT THU APR 16 2015
EAST WINDS 5 TO 15 KNOTS WILL NOT BE HAZARDOUS TO SMALL CRAFT TODAY.
&&
.HYDROLOGY...
ISSUED AT 1123 AM EDT THU APR 16 2015
THE LONE ADVISORY AT MAPLE RAPIDS CONTINUES TO SHOW IMPROVEMENT.
LIGHTER PRECIPITATION TODAY SHOULD NOT HAVE MUCH OF AN AFFECT ON
THE DROP THAT IS BEING EXPERIENCED. WE SHOULD SEE LEVELS DROP BELOW
ADVISORY CRITERIA LATE THIS EVENING.
BEYOND TWO DRY DAYS...FRIDAY AND SATURDAY...THE PATTERN GETS A BIT
ACTIVE AGAIN. WE COULD SEE SOME BENEFICIAL PRECIPITATION BETWEEN
SUNDAY AND TUESDAY. TOTAL AMOUNTS OVER THE NEXT 7 DAYS ARE NOT TOO
HEAVY. SOME MINOR FLUCTUATIONS MAY RESULT ON AREA RIVERS EARLY
NEXT WEEK...BUT AT THIS POINT I DO NOT SEE ANY REAL CAUSE FOR
CONCERN THROUGH THE PERIOD.
&&
.GRR WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LM...NONE.
&&
$$
UPDATE...WDM
SYNOPSIS...04
SHORT TERM...04
LONG TERM...OSTUNO
AVIATION...OSTUNO
HYDROLOGY...JAM
MARINE...04
AREA FORECAST DISCUSSION
NWS GRAND RAPIDS MI
856 AM EDT THU APR 16 2015
LATEST UPDATE...
UPDATE
.SYNOPSIS...
ISSUED AT 310 AM EDT THU APR 16 2015
LIGHT RAIN IS LIKELY TODAY ACROSS MUCH OF SOUTHWEST LOWER MICHIGAN
AS WEAK LOW PRESSURE MOVES NORTH FROM THE GULF. THE SHOWERS WILL
DIMINISH TONIGHT LEADING TO A DRY FRIDAY AND SATURDAY. RAIN IS BACK
IN THE PICTURE LATE IN THE WEEKEND AND EARLY NEXT WEEK AS A STRONGER
LOW MOVES EAST FROM THE PLAINS ACROSS THE GREAT LAKES.
TODAY WILL BE A BIT COOLER THAN WEDNESDAY; WE/LL SEE HIGHS IN THE
50S. TEMPERATURES WILL CLIMB TO AROUND 70 FRIDAY AND SATURDAY BEFORE
COOLER WEATHER DEVELOPS EARLY NEXT WEEK. MUCH OF NEXT WEEK WILL SEE
HIGHS ONLY AROUND 50.
&&
.UPDATE...
ISSUED AT 856 AM EDT THU APR 16 2015
I DID A QUICK UPDATE TO THE POP AND WEATHER GRIDS TO BETTER
REFLECT THE CURRENT RADAR TRENDS. THAT MEANS I INCREASED THE POP
TO NEAR 100 PCT OVER OUR NW CWA AND I HAVE AN AREA OF LOW POP
SOUTHWEST OF GRR (IT IS REALLY THERE) THAT MOVES NORTH WITH TIME.
THE ENTIRE AREA OF SHOWERS SHOULD BE MOSTLY OUT OF OUR CWA BY
MID AFTERNOON AS DRIER AIR MOVES IN AT MID LEVELS. THIS IDEA IS
MOSTLY BASED ON USING THE RAP MODEL LIFT IN THE DGZ WHERE THE AIR
IN THAT LAYER IS SATURATED. AT 8 AM THE AREA OF BEST LIFT IS NEAR
AND WEST OF US-131. BY 2 PM IT IS MOSTLY EAST OF I-75 BUT THERE IS
A SMALL AREA OF STRONG LIFT JUST SOUTH OF GRR AT THAT TIME WHICH
LIFTS TO NEAR LANSING BY 5 PM. THAT WILL HAVE TO BE WATCHED TO SEE
OF AN AREA OF SIGNIFICANT SHOWERS DOES DEVELOP THERE. I STILL EXPECT
NO THUNDERSTORM ACTIVITY TODAY.
&&
.SHORT TERM...(TODAY THROUGH SATURDAY)
ISSUED AT 310 AM EDT THU APR 16 2015
FORECAST CONCERNS DEAL WITH PCPN TRENDS TODAY. OVERALL...THE
FORECAST IS LARGELY ON TRACK ALTHOUGH QPF HAS BEEN TRIMMED A BIT.
00Z SOUNDING AT DTX WAS EXTREMELY DRY BELOW 450 MB AND EXPLAINS WHY
WE HAVEN/T SEEN MUCH RAIN AT THE SFC DESPITE ECHOS ACROSS THE LAKE
SHORE. THE SFC WAVE OF LOW PRESSURE TO THE SOUTH WILL MOVE OVER THE
CWA TODAY AND WE SHOULD SEE THE LOWER LEVELS OF THE ATM MOISTEN AND
RAIN TO DEVELOP. KGRR-88D SHOWS ECHO INTENSITY INCREASING A BIT AS
PCPN CONTINUES TO MOVE NORTH FROM INDIANA. SHORT RANGE NWP SHOWED
THE AREA OF THETA-E DECREASING WITH HEIGHT REMAINING SOUTH OF THE
CWA SO WE OPTED TO GO WITH NO THUNDER IN THE GRIDS TODAY. PCPN WILL
BEGIN TO MOVE EAST THIS AFTERNOON AND END EARLY IN THE EVENING. THIS
WILL LEAD TO A COUPLE OF DRY DAYS FRIDAY AND SATURDAY AS HIGH
PRESSURE NOSES IN FROM ONTARIO.
TEMPS WILL BE HELD DOWN A BIT BY THE SHOWERS TODAY AND WE`LL GO WITH
HIGHS IN THE MID TO UPPER 50S. UPPER HEIGHT RISES ASSOCIATED WITH
THE RIDGE WILL RESULT IN TEMPS AROUND 10 DEGREES WARMER FRIDAY AND
SATURDAY.
.LONG TERM...(SATURDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 310 AM EDT THU APR 16 2015
MODEL GUIDANCE REMAINS CONSISTENT IN SHOWING RAIN MOVING IN ON
SUNDAY WITH THE BEST CHANCE FOR WET WEATHER SUNDAY AFTERNOON AND
EVENING AS A SFC LOW AND UPPER TROUGH AXIS MOVES OVER LOWER
MICHIGAN. THE LOW CUTS OFF AND BECOMES VERTICALLY STACKED NORTH OF
LAKE SUPERIOR ON MONDAY WITH VORT ENERGY ROTATING THROUGH LOWER
MICHIGAN ON TUESDAY AND WEDNESDAY. GIVEN WET BULB ZERO HEIGHTS
CRASHING TO NEAR THE SFC...DO NOT BE SURPRISED TO SEE SOME SNOW
ACROSS AT LEAST THE NORTHERN ZONES TUESDAY THROUGH WEDNESDAY.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z FRIDAY MORNING)
ISSUED AT 736 AM EDT THU APR 16 2015
MVFR CONDITIONS WILL BECOME MORE WIDESPREAD TODAY AS SCATTERED SHOWERS
CONTINUE BUT THERE SHOULD FEW IF ANY AREAS OF IFR THROUGH TONIGHT.
WINDS WILL BE SOUTHEAST TODAY AOB 10 KNOTS THEN GO WEST BY THIS
EVENING AND DECREASE TO ABOUT 5 KNOTS.
&&
.MARINE...
ISSUED AT 310 AM EDT THU APR 16 2015
EAST WINDS 5 TO 15 KNOTS WILL NOT BE HAZARDOUS TO SMALL CRAFT TODAY.
&&
.HYDROLOGY...
ISSUED AT 310 AM EDT THU APR 16 2015
AROUND A TENTH OF AN INCH OF RAIN IS POSSIBLE TODAY. THIS WILL HAVE
A NEGLIGIBLE EFFECT ON AREA RIVERS.
&&
.GRR WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LM...NONE.
&&
$$
UPDATE...WDM
SYNOPSIS...04
SHORT TERM...04
LONG TERM...OSTUNO
AVIATION...OSTUNO
HYDROLOGY...04
MARINE...04
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
742 AM EDT THU APR 16 2015
.UPDATE...
ISSUED AT 657 AM EDT THU APR 16 2015
DECIDED TO PUT SPRINKLES INTO FORECAST OVER EASTERN CWA /ISQ-ERY/
MID MORNING INTO EARLY AFTN AS BAND OF SHOWERS OVER LOWER MICHIGAN
CONTINUES TO LIFT NORTHWARD. EVEN THOUGH SHRA WILL BE RUNNING INTO
THE DRY AIRMASS OVER AREA AS SEEN ON 00Z APX AND DTX RAOBS...THINK
ENOUGH FOCUS FM SHORTWAVE AND MOISTURE TRANSPORT AT H85-H7 IS GOING
TO END UP STRONG/PERSISTENT ENOUGH TO OUTWEIGH THE LOW-LEVEL DRY
AIR. VARIOUS HIGH RES MODELS AND THE 06Z/07Z HRRR REFLECTIVITY
OUTPUT POINT TO AT LEAST A BRIEF PERIOD OF LGT RAIN/SPRINKLES.
BEEFED UP SKY COVER SOME MORE AS WELL. OTHER THAN TWEAKS FOR VERY
SHORT TERM TEMP/DWPNT TRENDS...NO OTHER CHANGES WERE NEEDED TO
FORECAST.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 435 AM EDT THU APR 16 2015
SHORTWAVE RIDGING PERSISTS TODAY BTWN NORTHERN STREAM SHORTWAVE THAT
CROSSES MANITOBA/NORTHERN ONTARIO AND CUTOFF LOW OVER FOUR CORNERS
OF SW CONUS. WEAK AREAS OF VORTICITY LIFTING INTO THE RIDGE BRINGING
A PUSH OF MID-LEVEL MOISTURE ADVECTION AROUND H7. DECENT AREA OF
SHRA IS LIFTING NORTHWARD OVER WESTERN LOWER MICHIGAN ON NORTH EDGE
OF MOISTURE TRANSPORT AT H85-H7 AND THIS COULD BRING VIRGA OR A FEW
SPRINKLES TO EASTERN CWA...POSSIBLY AS FAR WEST AS KESC PER HRRR
MODEL LATE MORNING INTO EARLY AFTN. ELSEWHERE WILL CERTAINLY BE MORE
CLOUDS THAN LAST COUPLE DAYS AS CIRRUS AND MORE PRONOUNCED AREA OF
AC/AS OVER MN SLIDES IN FOR THE AFTN. EVEN SO THOUGH...WARM START
SHOULD STILL ALLOW MAX TEMPS TO REACH WELL INTO THE 60S. RH VALUES A
BIT HIGHER THAN BONE DRY CONDITIONS SEEN TUE/WED WHERE RH BOTTOMED
OUT AROUND 10 PCT OVER INTERIOR WEST. FOR TODAY IN THOSE AREAS...
EXPECT MAINLY 18-25 PCT RANGE AT THE LOW-END. WINDS LESS THAN 10 MPH
MOST AREAS WITH LOCAL LAKE BREEZES CNTRL. OVERALL APPEARS TO NOT BE
AS MUCH OF ISSUE WITH FIRE WEATHER TODAY COMPARED TO TUE OR WED.
NORTHERN STREAM SHORTWAVE CROSSES NORTHERN ONTARIO TONIGHT WITH
TAIL OF ENHANCED CLOUD GRAZING CWA...ALONG WITH THE PASSAGE OF SFC
TROUGH...MORE OF A WIND SHIFT FM SW TO NW LATE TONIGHT. SINCE 1000-
700MB LAPSE RATES ARE HIGH...OVER 7C/KM BY LATE AFTN...AND FORCING
IS MOVING THROUGH WITH SUFFICIENT MOISTURE ALOFT...THINK THERE IS A
CHANCE OF SPRINKLES/VIRGA THIS EVENING AS THE FORCING MOVES
THROUGH...PERHAPS SIMILAR TO WHAT OCCURRED MON AFTN/EVENING. THAT
SAID...WINDS IN MIXED LAYER THIS EVENING DO INCREASE BY 03Z WITH 25-
30 KTS AT TOP PARTS OF THE MIXED LAYER. SO...FEASIBLE THAT GUSTY
WINDS COULD OCCUR IN THE VCNTY OF ANY WELL DEVELOPED CU OR
VIRGA/SPRINKLES. ALL FORCING IS OUT OF HERE BY MIDNIGHT AND SCT-BKN
CLOUDS SHOULD EXIT OVERNIGHT. SKIES WILL BE MAINLY CLEAR BY DAYBREAK
ON FRIDAY. LOWS TONIGHT SHOULD REMAIN ABOVE FREEZING ALL AREAS GIVEN
THE WINDS AND CLOUDS MOST OF THE NIGHT AND LACK OF COLD AIR BEHIND
THE TROUGH.
.LONG TERM...(THURSDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 436 PM EDT WED APR 15 2015
AFTER A QUIET AND GENERALLY WARM REST OF THIS WEEK...SIGNIFICANT
AMPLIFICATION OF THE FLOW IS EXPECTED THIS WEEKEND AND EARLY NEXT
WEEK AS A SHARP RIDGE BUILDS THRU WRN CANADA. THIS WILL FORCE A DEEP
TROF TO DEVELOP DOWNSTREAM WITH AXIS ROUGHLY OVER THE MISSISSIPPI
VALLEY BY MON. TYPICAL FOR THIS TIME OF YEAR...CLOSED LOWS
FREQUENTLY DEVELOP...AND THIS TROF WILL QUICKLY EVOLVE IN THAT
DIRECTION AS MAJORITY OF GUIDANCE INCLUDING GFS/GEM ENSEMBLES SHOW
EVOLUTION INTO A LARGE/COLD MID-LEVEL LOW OVER THE VICINITY OF THE
UPPER GREAT LAKES. MAY BE DIFFICULT TO DISLODGE THE LOW NEXT WEEK
ONCE IT DEVELOPS. SO...AFTER A WARM/DRY REST OF THIS WEEK...NEXT
WEEK WILL BE COLD AND GENERALLY UNSETTLED WITH PERIODIC CHANCES OF
SNOW AND RAIN SHOWERS. FROM A PCPN PERSPECTIVE...THE BIGGEST
CHALLENGE IS HOW THE SHARP PATTERN AMPLIFICATION INTERACTS WITH WHAT
IS CURRENTLY AN IMPRESSIVE LOOKING TROF CLOSING OFF OVER UT/CO.
MEDIUM RANGE GUIDANCE TODAY IS IN MUCH BETTER AGREEMENT IN SHOWING
THE AMPLIFICATION OF THE FLOW PICKING UP THE MID-LEVEL LOW AND
FORCING THE OPENED UP SYSTEM/REMNANT ENERGY NE INTO THE GREAT LAKES
REGION. RANGE OF POSSIBILITIES STILL INCLUDE A SIGNIFICANT RAIN
EVENT TO A RAIN CHANGING TO ACCUMULATING SNOW EVENT TO MINIMAL PCPN
IF THE SRN ENERGY DOES NOT LIFT FAR ENOUGH N AND W WITHIN THE
AMPLIFYING PATTERN. OPERATIONAL MEDIUM RANGE MODELS WEAKEN THE
ENERGY DRAMATICALLY AS IT LIFTS NE (WILL BE INTERESTING TO SEE IF
THAT ACTUALLY HAPPENS)...SO THE LOWEST PROBABILITY OUTCOME RIGHT NOW
IS ONE THAT BRINGS A SIGNIFICANT PCPN PRODUCING SYSTEM WITH A
PROMINENT DEFORMATION PCPN SHIELD INTO THE UPPER LAKES EARLY NEXT
WEEK. THAT SAID...THERE HAVE BEEN AND THERE STILL ARE SOME GFS/GEM
ENSEMBLES THAT DO SHOW SUCH A SCENARIO...SO IT CAN`T BE RULED OUT.
BEGINNING THU NIGHT...TAIL END OF SHORTWAVE TRACKING FROM HUDSON BAY
INTO QUEBEC WILL PASS ACROSS THE AREA THU NIGHT. FORCING FROM THE
RIGHT ENTRANCE OF AN UPPER JET STREAK AND MAIN DEEP LAYER QVECTOR
CONVERGENCE...WEAK AT THAT...PASS N OF THE AREA...SUPPORTING BEST
CHC OF -SHRA N OF HERE. ACROSS UPPER MI...VERY WEAK FORCING/WEAK
FRONTAL BOUNDARY AND WEAK MOISTURE TRANSPORT ALL SUGGEST PROSPECT OF
ANY PCPN IS VERY LIMITED AS SHORTWAVE PASSES. THUS...WILL RETAIN DRY
FCST FOR THU NIGHT.
IN THE MAIN FLOW TO THE N...ANOTHER SHORTWAVE IS FCST TO TRACK FROM
THE CANADIAN ROCKIES THU AFTN TO NRN ONTARIO FRI. MODELS HAVE
TRENDED TO MUCH BETTER AGREEMENT ON THIS WAVE WITH GEM/GFS/NAM
MOVING TO THE ECMWF SCENARIO WHICH HAS BEEN FARTHER N THAN THOSE
MODELS FOR SEVERAL RUNS. WITH THE TRACK OF THE SHORTWAVE JUST N OF
LAKE SUPERIOR...BEST FORCING AND POTENTIAL FOR PCPN WILL PASS BY TO
THE N. REMOVED SCHC POPS FROM INHERITED FCST IN FAVOR OF DRY
WEATHER. EXPECT HIGH TEMPS FRI IN THE 60S AWAY FROM LAKE MODERATION.
A FEW SPOTS MAY REACH 70F. INTERIOR RH SHOULD FALL TO 25-30PCT...
AND WINDS MAY BE A LITTLE GUSTY TO 15-20MPH AT TIMES...KEEPING FIRE
WX A CONCERN.
IN THE WAKE OF THE SHORTWAVE...HIGH PRES BUILDS INTO THE AREA FOR
SAT. WITH THE HIGH ENDING UP OVER LAKE SUPERIOR IN THE AFTN...IT
WILL BE A MUCH COOLER DAY NEAR LAKE SUPERIOR...ESPECIALLY FROM THE
KEWEENAW EASTWARD. RIGHT ALONG THE SHORE...TEMPS SHOULDN`T GET OUT
OF THE 30S. IN THE INTERIOR W HALF...TEMPS SHOULD RISE TO AROUND 60F
UNDER SUNNY SKIES.
SUN/MON...WILL CONTINUE TO UTILIZE A CONSENSUS APPROACH OF CURRENT
AND RECENT MEDIUM RANGE GUIDANCE FOR THE EVOLUTION OF THE SRN
ROCKIES ENERGY INTO THE GREAT LAKES AHEAD OF THE TROF AMPLIFICATION
OCCURRING INTO THE PLAINS/MISSISSIPPI VALLEY. IT APPEARS THERE MAY
END UP BEING TWO SURGES OF PCPN OR SFC LOW PRES WAVES...ONE
ASSOCIATED WITH LEAD ENERGY SWINGING UP FROM MEXICO AND A SECOND
ASSOCIATED WITH THE MAIN REMNANT OF THE ROCKIES MID LEVEL LOW.
LATEST GUIDANCE SUGGESTS RAIN WILL BEGIN SPREADING INTO UPPER MI SUN
AND THEN CONTINUE INTO MON. AIR MASS SHOULD COOL ENOUGH TO ALLOW
SOME SNOW TO BEGIN MIXING WITH THE RAIN OVER THE W ON MON. PTYPE
WILL THEN BECOME ALL SNOW ACROSS THE FCST AREA MON NIGHT FOR
WHATEVER PCPN LINGERS.
TUE/WED...LARGE/COLD MID-LEVEL LOW WILL HAVE DEVELOPED AND WILL BE
CENTERED IN THE VCNTY OF THE UPPER GREAT LAKES. COLD AIR
ALOFT/SPRING DAYTIME HEATING AND POTENTIAL OF SHORTWAVES ROTATING
THRU THE AREA WITHIN THE LARGE MID-LEVEL LOW CIRCULATION SUGGEST AT
LEAST SCT SHOWERY PCPN (MOSTLY SNOW BUT SOME RAIN AS WELL DURING
PEAK HEATING) BOTH DAYS WITH BEST COVERAGE IN THE AFTN INLAND FROM
LAKE SUPERIOR WHERE HEATING IS BEST. HIGH TEMPS BOTH DAYS SHOULD BE
IN THE MID 30S TO MID 40S...WARMEST SCNTRL.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z FRIDAY MORNING)
ISSUED AT 742 AM EDT THU APR 16 2015
EVEN THOUGH MID TO HIGH CLOUDS WILL THICKEN THROUGH THIS EVENING AS
A WEAK UPR DISTURBANCE MOVES TOWARD THE UPR LKS AND MOISTURE
INCREASES ALOFT...LINGERING LLVL DRY AIR ASSOCIATED WITH A SFC HI
PRES RDG WL BRING CONTINUED VFR CONDITIONS. EXPECT A SFC TROUGH TO
CROSS UPR MICHIGAN TONIGHT WITH A WIND SHIFT FM SW TO NW. WINDS
SHOULD STAY LIGHT THOUGH. IT IS POSSIBLE THERE COULD BE A LGT SHOWER
OR SPRINKLE AROUND EARLY THIS EVENING AHEAD OF THE FRONT.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 435 AM EDT THU APR 16 2015
NO WIDESPREAD GALES ARE EXPECTED THROUGH THE FORECAST PERIOD...BUT
THERE WILL BE A FEW PERIODS OF STRONGER WINDS STARTING THIS WEEKEND.
WINDS EXPECTED TO REMAIN AT OR BLO 20 KTS THROUGH FRIDAY NIGHT AS
PRESSURE GRADIENT IS WEAK. HIGH PRESSURE MOVING ACROSS ON SATURDAY
WITH LOW PRESSURE FOLLOWING OVER SCNTRL CANADA ON SUNDAY WILL RESULT
IN SETUP FOR STRONGER EAST-NORTHEAST WINDS TO 30 KTS OVER WESTERN LK
SUPERIOR SATURDAY AND SATURDAY NIGHT. STRONGEST WINDS WILL BE TOWARD
HEAD OF LK SUPERIOR NEAR DULUTH AND SUPERIOR. BY SUNDAY...AS THE LOW
PRESSURE SYSTEM APPROACHES...SOUTHEAST WINDS TO 30 KTS WILL BE
POSSIBLE OVER EASTERN HALF OF LK SUPERIOR WHILE WINDS DIMINISH IN
THE WEST. THE LOW CROSSES THE UPPER GREAT LAKES BY MONDAY WHILE
MERGING WITH ANOTHER LOW LIFTING IN FM THE CENTRAL PLAINS. EXPECT
WEST WINDS UP TO 30 KTS OVER MUCH OF THE LAKE LATER MONDAY INTO
TUESDAY IN WAKE OF THIS COMBINED LOW AS IT MOVES TO THE LOWER GREAT
LAKES.
&&
.HYDROLOGY...
ISSUED AT 332 PM EDT WED APR 15 2015
SEEMS THAT WITHOUT ANY SIGNIFICANT ADDITIONAL PRECIPITATION ADDED TO
THE ONGOING SNOWMELT...AT LEAST FOR THE REST OF THIS WEEK...MAINLY
LOOKING AT A FEW BANKFULL ISSUES ON SOME RIVERS WITH CONTINUATION OF
LOW-END ADVISORIES. BELOW NORMAL TEMPERATURES ARE EXPECTED MONDAY
THROUGH MUCH OF NEXT WEEK...WHICH WILL LIMIT MELTING OF ANY
REMAINING SNOW PACK AND REDUCE RIVER LEVELS.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
UPDATE...JLA
SHORT TERM...JLA
LONG TERM...ROLFSON
AVIATION...JLA
MARINE...JLA
HYDROLOGY...TITUS
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
658 AM EDT THU APR 16 2015
.UPDATE...
ISSUED AT 657 AM EDT THU APR 16 2015
DECIDED TO PUT SPRINKLES INTO FORECAST OVER EASTERN CWA /ISQ-ERY/
MID MORNING INTO EARLY AFTN AS BAND OF SHOWERS OVER LOWER MICHIGAN
CONTINUES TO LIFT NORTHWARD. EVEN THOUGH SHRA WILL BE RUNNING INTO
THE DRY AIRMASS OVER AREA AS SEEN ON 00Z APX AND DTX RAOBS...THINK
ENOUGH FOCUS FM SHORTWAVE AND MOISTURE TRANSPORT AT H85-H7 IS GOING
TO END UP STRONG/PERSISTENT ENOUGH TO OUTWEIGH THE LOW-LEVEL DRY
AIR. VARIOUS HIGH RES MODELS AND THE 06Z/07Z HRRR REFLECTIVITY
OUTPUT POINT TO AT LEAST A BRIEF PERIOD OF LGT RAIN/SPRINKLES.
BEEFED UP SKY COVER SOME MORE AS WELL. OTHER THAN TWEAKS FOR VERY
SHORT TERM TEMP/DWPNT TRENDS...NO OTHER CHANGES WERE NEEDED TO
FORECAST.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 435 AM EDT THU APR 16 2015
SHORTWAVE RIDGING PERSISTS TODAY BTWN NORTHERN STREAM SHORTWAVE THAT
CROSSES MANITOBA/NORTHERN ONTARIO AND CUTOFF LOW OVER FOUR CORNERS
OF SW CONUS. WEAK AREAS OF VORTICITY LIFTING INTO THE RIDGE BRINGING
A PUSH OF MID-LEVEL MOISTURE ADVECTION AROUND H7. DECENT AREA OF
SHRA IS LIFTING NORTHWARD OVER WESTERN LOWER MICHIGAN ON NORTH EDGE
OF MOISTURE TRANSPORT AT H85-H7 AND THIS COULD BRING VIRGA OR A FEW
SPRINKLES TO EASTERN CWA...POSSIBLY AS FAR WEST AS KESC PER HRRR
MODEL LATE MORNING INTO EARLY AFTN. ELSEWHERE WILL CERTAINLY BE MORE
CLOUDS THAN LAST COUPLE DAYS AS CIRRUS AND MORE PRONOUNCED AREA OF
AC/AS OVER MN SLIDES IN FOR THE AFTN. EVEN SO THOUGH...WARM START
SHOULD STILL ALLOW MAX TEMPS TO REACH WELL INTO THE 60S. RH VALUES A
BIT HIGHER THAN BONE DRY CONDITIONS SEEN TUE/WED WHERE RH BOTTOMED
OUT AROUND 10 PCT OVER INTERIOR WEST. FOR TODAY IN THOSE AREAS...
EXPECT MAINLY 18-25 PCT RANGE AT THE LOW-END. WINDS LESS THAN 10 MPH
MOST AREAS WITH LOCAL LAKE BREEZES CNTRL. OVERALL APPEARS TO NOT BE
AS MUCH OF ISSUE WITH FIRE WEATHER TODAY COMPARED TO TUE OR WED.
NORTHERN STREAM SHORTWAVE CROSSES NORTHERN ONTARIO TONIGHT WITH
TAIL OF ENHANCED CLOUD GRAZING CWA...ALONG WITH THE PASSAGE OF SFC
TROUGH...MORE OF A WIND SHIFT FM SW TO NW LATE TONIGHT. SINCE 1000-
700MB LAPSE RATES ARE HIGH...OVER 7C/KM BY LATE AFTN...AND FORCING
IS MOVING THROUGH WITH SUFFICIENT MOISTURE ALOFT...THINK THERE IS A
CHANCE OF SPRINKLES/VIRGA THIS EVENING AS THE FORCING MOVES
THROUGH...PERHAPS SIMILAR TO WHAT OCCURRED MON AFTN/EVENING. THAT
SAID...WINDS IN MIXED LAYER THIS EVENING DO INCREASE BY 03Z WITH 25-
30 KTS AT TOP PARTS OF THE MIXED LAYER. SO...FEASIBLE THAT GUSTY
WINDS COULD OCCUR IN THE VCNTY OF ANY WELL DEVELOPED CU OR
VIRGA/SPRINKLES. ALL FORCING IS OUT OF HERE BY MIDNIGHT AND SCT-BKN
CLOUDS SHOULD EXIT OVERNIGHT. SKIES WILL BE MAINLY CLEAR BY DAYBREAK
ON FRIDAY. LOWS TONIGHT SHOULD REMAIN ABOVE FREEZING ALL AREAS GIVEN
THE WINDS AND CLOUDS MOST OF THE NIGHT AND LACK OF COLD AIR BEHIND
THE TROUGH.
.LONG TERM...(THURSDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 436 PM EDT WED APR 15 2015
AFTER A QUIET AND GENERALLY WARM REST OF THIS WEEK...SIGNIFICANT
AMPLIFICATION OF THE FLOW IS EXPECTED THIS WEEKEND AND EARLY NEXT
WEEK AS A SHARP RIDGE BUILDS THRU WRN CANADA. THIS WILL FORCE A DEEP
TROF TO DEVELOP DOWNSTREAM WITH AXIS ROUGHLY OVER THE MISSISSIPPI
VALLEY BY MON. TYPICAL FOR THIS TIME OF YEAR...CLOSED LOWS
FREQUENTLY DEVELOP...AND THIS TROF WILL QUICKLY EVOLVE IN THAT
DIRECTION AS MAJORITY OF GUIDANCE INCLUDING GFS/GEM ENSEMBLES SHOW
EVOLUTION INTO A LARGE/COLD MID-LEVEL LOW OVER THE VICINITY OF THE
UPPER GREAT LAKES. MAY BE DIFFICULT TO DISLODGE THE LOW NEXT WEEK
ONCE IT DEVELOPS. SO...AFTER A WARM/DRY REST OF THIS WEEK...NEXT
WEEK WILL BE COLD AND GENERALLY UNSETTLED WITH PERIODIC CHANCES OF
SNOW AND RAIN SHOWERS. FROM A PCPN PERSPECTIVE...THE BIGGEST
CHALLENGE IS HOW THE SHARP PATTERN AMPLIFICATION INTERACTS WITH WHAT
IS CURRENTLY AN IMPRESSIVE LOOKING TROF CLOSING OFF OVER UT/CO.
MEDIUM RANGE GUIDANCE TODAY IS IN MUCH BETTER AGREEMENT IN SHOWING
THE AMPLIFICATION OF THE FLOW PICKING UP THE MID-LEVEL LOW AND
FORCING THE OPENED UP SYSTEM/REMNANT ENERGY NE INTO THE GREAT LAKES
REGION. RANGE OF POSSIBILITIES STILL INCLUDE A SIGNIFICANT RAIN
EVENT TO A RAIN CHANGING TO ACCUMULATING SNOW EVENT TO MINIMAL PCPN
IF THE SRN ENERGY DOES NOT LIFT FAR ENOUGH N AND W WITHIN THE
AMPLIFYING PATTERN. OPERATIONAL MEDIUM RANGE MODELS WEAKEN THE
ENERGY DRAMATICALLY AS IT LIFTS NE (WILL BE INTERESTING TO SEE IF
THAT ACTUALLY HAPPENS)...SO THE LOWEST PROBABILITY OUTCOME RIGHT NOW
IS ONE THAT BRINGS A SIGNIFICANT PCPN PRODUCING SYSTEM WITH A
PROMINENT DEFORMATION PCPN SHIELD INTO THE UPPER LAKES EARLY NEXT
WEEK. THAT SAID...THERE HAVE BEEN AND THERE STILL ARE SOME GFS/GEM
ENSEMBLES THAT DO SHOW SUCH A SCENARIO...SO IT CAN`T BE RULED OUT.
BEGINNING THU NIGHT...TAIL END OF SHORTWAVE TRACKING FROM HUDSON BAY
INTO QUEBEC WILL PASS ACROSS THE AREA THU NIGHT. FORCING FROM THE
RIGHT ENTRANCE OF AN UPPER JET STREAK AND MAIN DEEP LAYER QVECTOR
CONVERGENCE...WEAK AT THAT...PASS N OF THE AREA...SUPPORTING BEST
CHC OF -SHRA N OF HERE. ACROSS UPPER MI...VERY WEAK FORCING/WEAK
FRONTAL BOUNDARY AND WEAK MOISTURE TRANSPORT ALL SUGGEST PROSPECT OF
ANY PCPN IS VERY LIMITED AS SHORTWAVE PASSES. THUS...WILL RETAIN DRY
FCST FOR THU NIGHT.
IN THE MAIN FLOW TO THE N...ANOTHER SHORTWAVE IS FCST TO TRACK FROM
THE CANADIAN ROCKIES THU AFTN TO NRN ONTARIO FRI. MODELS HAVE
TRENDED TO MUCH BETTER AGREEMENT ON THIS WAVE WITH GEM/GFS/NAM
MOVING TO THE ECMWF SCENARIO WHICH HAS BEEN FARTHER N THAN THOSE
MODELS FOR SEVERAL RUNS. WITH THE TRACK OF THE SHORTWAVE JUST N OF
LAKE SUPERIOR...BEST FORCING AND POTENTIAL FOR PCPN WILL PASS BY TO
THE N. REMOVED SCHC POPS FROM INHERITED FCST IN FAVOR OF DRY
WEATHER. EXPECT HIGH TEMPS FRI IN THE 60S AWAY FROM LAKE MODERATION.
A FEW SPOTS MAY REACH 70F. INTERIOR RH SHOULD FALL TO 25-30PCT...
AND WINDS MAY BE A LITTLE GUSTY TO 15-20MPH AT TIMES...KEEPING FIRE
WX A CONCERN.
IN THE WAKE OF THE SHORTWAVE...HIGH PRES BUILDS INTO THE AREA FOR
SAT. WITH THE HIGH ENDING UP OVER LAKE SUPERIOR IN THE AFTN...IT
WILL BE A MUCH COOLER DAY NEAR LAKE SUPERIOR...ESPECIALLY FROM THE
KEWEENAW EASTWARD. RIGHT ALONG THE SHORE...TEMPS SHOULDN`T GET OUT
OF THE 30S. IN THE INTERIOR W HALF...TEMPS SHOULD RISE TO AROUND 60F
UNDER SUNNY SKIES.
SUN/MON...WILL CONTINUE TO UTILIZE A CONSENSUS APPROACH OF CURRENT
AND RECENT MEDIUM RANGE GUIDANCE FOR THE EVOLUTION OF THE SRN
ROCKIES ENERGY INTO THE GREAT LAKES AHEAD OF THE TROF AMPLIFICATION
OCCURRING INTO THE PLAINS/MISSISSIPPI VALLEY. IT APPEARS THERE MAY
END UP BEING TWO SURGES OF PCPN OR SFC LOW PRES WAVES...ONE
ASSOCIATED WITH LEAD ENERGY SWINGING UP FROM MEXICO AND A SECOND
ASSOCIATED WITH THE MAIN REMNANT OF THE ROCKIES MID LEVEL LOW.
LATEST GUIDANCE SUGGESTS RAIN WILL BEGIN SPREADING INTO UPPER MI SUN
AND THEN CONTINUE INTO MON. AIR MASS SHOULD COOL ENOUGH TO ALLOW
SOME SNOW TO BEGIN MIXING WITH THE RAIN OVER THE W ON MON. PTYPE
WILL THEN BECOME ALL SNOW ACROSS THE FCST AREA MON NIGHT FOR
WHATEVER PCPN LINGERS.
TUE/WED...LARGE/COLD MID-LEVEL LOW WILL HAVE DEVELOPED AND WILL BE
CENTERED IN THE VCNTY OF THE UPPER GREAT LAKES. COLD AIR
ALOFT/SPRING DAYTIME HEATING AND POTENTIAL OF SHORTWAVES ROTATING
THRU THE AREA WITHIN THE LARGE MID-LEVEL LOW CIRCULATION SUGGEST AT
LEAST SCT SHOWERY PCPN (MOSTLY SNOW BUT SOME RAIN AS WELL DURING
PEAK HEATING) BOTH DAYS WITH BEST COVERAGE IN THE AFTN INLAND FROM
LAKE SUPERIOR WHERE HEATING IS BEST. HIGH TEMPS BOTH DAYS SHOULD BE
IN THE MID 30S TO MID 40S...WARMEST SCNTRL.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z THURSDAY NIGHT)
ISSUED AT 208 AM EDT THU APR 16 2015
ALTHOUGH THERE WL BE SOME THICKENING HI/MID CLDS LATER TODAY AS A WEAK
UPR DISTURBANCE MOVES TOWARD THE UPR LKS...LINGERING LLVL DRY AIR
ASSOCIATED WITH A SFC HI PRES RDG WL BRING CONTINUED VFR CONDITIONS.
STRONGER S WINDS ABOVE LIGHTER GROUND LVL WINDS WITHIN A NEAR SFC
STABLE LYR CAUSED BY NOCTURNAL COOLING WL ALLOW FOR SOME LLWS AT THE
SITES EARLY THIS MRNG...BUT WINDS WL DIMINISH SGNFTLY BY SUNRISE...
ENDING THE LLWS.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 435 AM EDT THU APR 16 2015
NO WIDESPREAD GALES ARE EXPECTED THROUGH THE FORECAST PERIOD...BUT
THERE WILL BE A FEW PERIODS OF STRONGER WINDS STARTING THIS WEEKEND.
WINDS EXPECTED TO REMAIN AT OR BLO 20 KTS THROUGH FRIDAY NIGHT AS
PRESSURE GRADIENT IS WEAK. HIGH PRESSURE MOVING ACROSS ON SATURDAY
WITH LOW PRESSURE FOLLOWING OVER SCNTRL CANADA ON SUNDAY WILL RESULT
IN SETUP FOR STRONGER EAST-NORTHEAST WINDS TO 30 KTS OVER WESTERN LK
SUPERIOR SATURDAY AND SATURDAY NIGHT. STRONGEST WINDS WILL BE TOWARD
HEAD OF LK SUPERIOR NEAR DULUTH AND SUPERIOR. BY SUNDAY...AS THE LOW
PRESSURE SYSTEM APPROACHES...SOUTHEAST WINDS TO 30 KTS WILL BE
POSSIBLE OVER EASTERN HALF OF LK SUPERIOR WHILE WINDS DIMINISH IN
THE WEST. THE LOW CROSSES THE UPPER GREAT LAKES BY MONDAY WHILE
MERGING WITH ANOTHER LOW LIFTING IN FM THE CENTRAL PLAINS. EXPECT
WEST WINDS UP TO 30 KTS OVER MUCH OF THE LAKE LATER MONDAY INTO
TUESDAY IN WAKE OF THIS COMBINED LOW AS IT MOVES TO THE LOWER GREAT
LAKES.
&&
.HYDROLOGY...
ISSUED AT 332 PM EDT WED APR 15 2015
SEEMS THAT WITHOUT ANY SIGNIFICANT ADDITIONAL PRECIPITATION ADDED TO
THE ONGOING SNOWMELT...AT LEAST FOR THE REST OF THIS WEEK...MAINLY
LOOKING AT A FEW BANKFULL ISSUES ON SOME RIVERS WITH CONTINUATION OF
LOW-END ADVISORIES. BELOW NORMAL TEMPERATURES ARE EXPECTED MONDAY
THROUGH MUCH OF NEXT WEEK...WHICH WILL LIMIT MELTING OF ANY
REMAINING SNOW PACK AND REDUCE RIVER LEVELS.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
UPDATE...JLA
SHORT TERM...JLA
LONG TERM...ROLFSON
AVIATION...KC
MARINE...JLA
HYDROLOGY...TITUS
AREA FORECAST DISCUSSION
NWS HASTINGS NE
807 AM CDT THU APR 16 2015
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 412 AM CDT THU APR 16 2015
RADAR SHOWS SHOWERS AND THUNDERSTORMS MOVING NORTH/NORTHEAST WITH
DEVELOPMENT ON THE SOUTH END OF THE MAIN CLUSTER OF THUNDERSTORMS.
SURFACE ANALYSIS SHOWS A LOW PRESSURE SYSTEM ACROSS WESTERN KANSAS
WITH A COLD FRONT EXTENDING TO THE NORTH ACROSS NEBRASKA.
AN UPPER LEVEL LOW IN THE IN THE FOUR CORNERS REGION WILL DRIFT
TOWARD THE EAST TODAY AND TONIGHT. IN ADVANCE OF THE UPPER LOW A FEW
WAVES WILL MOVE ACROSS THE AREA THROUGH TONIGHT. THE NAM AND GFS
BOTH SPREAD THE PRECIPITATION ACROSS THE FORECAST AREA THROUGH THE
MORNING HOURS AS THE FIRST OF THE WAVES MOVE THROUGH THE FORECAST
AREA. THE RAP AND THE 4KM WRF BOTH INDICATE THIS INITIAL GROUP OF
THUNDERSTORMS WILL MOVE THROUGH AND ALTHOUGH THERE MAY BE SOME
ISOLATED THUNDERSTORMS AROUND...THERE COULD BE A BREAK THIS MORNING.
HAVE KEPT POPS ACROSS THE AREA...BUT DID LOWER THEM A BIT THIS
MORNING.
THE NEXT WAVE WILL MOVE INTO THE AREA THIS AFTERNOON AND EVENING.
THUNDERSTORMS SHOULD DEVELOP IN WESTERN KANSAS AND SPREAD INTO THE
AREA DURING THE AFTERNOON. LATE AFTERNOON INTO THE EARLY EVENING THE
MUCAPE INCREASES TO NEARLY 2500 J/KG MAINLY ACROSS KANSAS. THIS IS
THE AREA WITH THE BEST CHANCE FOR SOME SEVERE WEATHER. ANOTHER UPPER
LEVEL WAVE PUSHES INTO THE AREA LATE TONIGHT. SHOWERS AND
THUNDERSTORMS ARE EXPECTED ACROSS THE AREA LATE TONIGHT.
.LONG TERM...(FRIDAY THROUGH WEDNESDAY)
ISSUED AT 412 AM CDT THU APR 16 2015
A PAIR OF UPPER LEVEL LOWS FORECAST TO TRACK ACROSS THE SOUTHERN
HALF OF THE COUNTRY WILL BRING SOME SIGNIFICANT CHANCES FOR
BENEFICIAL RAINFALL TO THE REGION OVER THE NEXT WEEK OR SO. THE
FIRST OF THESE LOW PRESSURE SYSTEMS IS CURRENTLY SPINNING ACROSS THE
DESERT SOUTHWEST...AND ALREADY HAVING AN IMPACT ON THE LOCAL
WEATHER. WITH THIS LOW CUT OFF FROM THE MAIN UPPER LEVEL FLOW ACROSS
CANADA...EXPECT VERY SLOW PROGRESSION TOWARDS THE EAST TO RESULT IN
MULTIPLE DAYS OF UNSETTLED WEATHER ACROSS THE REGION.
WITH MOIST SOUTHERLY FLOW AHEAD OF THIS SYSTEM...DEWPOINTS HAVE
SURGED INTO THE 50S ACROSS MUCH OF THE LOCAL AREA AND EXPECT THE
ASSOCIATED INSTABILITY TO HELP AID IN THE FORMATION OF THUNDERSTORMS
BOTH FRIDAY AND SATURDAY. THAT SAID...WITH MUCH BETTER SHEAR TO WORK
WITH ON FRIDAY AFTERNOON/EVENING...THIS APPEARS TO BE THE BEST SHOT
FOR MORE WIDESPREAD STRONG AND POTENTIALLY SEVERE STORMS ACROSS THE
REGION...AND NOT SURPRISINGLY ROUGHLY THE SOUTHERN HALF OF THE
FORECAST AREA IS NOW OUTLOOKED BY SPC. IF REALIZED...THE MAIN
HAZARDS ARE LIKELY TO BE LARGE HAIL AND STRONG WIND GUSTS.
WHILE STILL NOT OUT OF THE QUESTION FOR SATURDAY...ADDITIONAL STRONG
TO MARGINALLY SEVERE THUNDERSTORMS WILL BE POSSIBLE DURING THE
AFTERNOON AND EVENING HOURS...BUT DUE TO DIMINISHED SHEAR
VALUES...THINK THE COVERAGE OF THESE STRONGER STORMS WILL BE MUCH
MORE LIMITED. EVEN SO...WIDESPREAD BENEFICIAL RAINFALL IS
ANTICIPATED FOR THE ENTIRE REGION BOTH DAYS...WITH STORM TOTAL
PRECIPITATION AMOUNTS OVER 2 INCHES EXPECTED TO BE FAIRLY WIDESPREAD
BY THE TIME THE RAINFALL ENDS AND THE RESPONSIBLE LOW PRESSURE
SYSTEM TRACKS EASTWARDS SUNDAY AFTERNOON.
THIS LOW PRESSURE SYSTEM WILL BE SHIFTED EASTWARD BY A FAIRLY STRONG
COLD FRONT FORECAST TO DROP SOUTH ACROSS THE LOCAL AREA SUNDAY. THIS
COLD FRONT WILL BRING SIGNIFICANTLY COOLER TEMPERATURES TO START THE
NEW WORK WEEK WITH POTENTIALLY SOME NEAR FREEZING TEMPERATURES
CURRENTLY FORECAST FOR BOTH MONDAY AND TUESDAY MORNINGS. WHILE
ACTUAL FROST MAY NOT DEVELOP EITHER DAY...THESE COOLER TEMPERATURES
WILL BE SOMETHING TO MONITOR AS SENSITIVE VEGETATION MAY BE
IMPACTED. ADDITIONALLY...WITH STRONG NORTHWESTERLY WINDS BEHIND THIS
FRONT AND DRIER AIR ADVECTING IN FROM THE NORTH...COULD EVENTUALLY
SEE SOME NEAR CRITICAL FIRE WEATHER CONDITIONS REALIZED ACROSS
ROUGHLY THE NORTHWESTERN HALF OF THE LOCAL AREA. BECAUSE BOTH OF
THESE POTENTIAL HAZARDS ARE STILL SEVERAL DAYS OUT AND
MARGINAL...OPTED NOT TO MENTION EITHER OF THESE IN THE MORNING HWO.
THEREAFTER...RAINFALL CHANCES WILL INCREASE MIDWEEK AS ANOTHER UPPER
LEVEL LOW MOVES INTO THE DESERT SOUTHWEST AND MOISTURE INCREASES
ACROSS THE REGION.
&&
.AVIATION...(FOR THE 12Z KGRI/KEAR TAFS THROUGH 12Z FRIDAY MORNING)
ISSUED AT 806 AM CDT THU APR 16 2015
...UPDATE TO 12Z TAF DISCUSSION...
SINCE THE PREVIOUS DISCUSSION WAS ISSUED A FEW HOURS
AGO...AVIATION CONDITIONS HAVE TAKEN A NOTABLE DOWNWARD TURN WITH
PREVAILING LIFR/IFR CEILING AND IFR/MVFR VISIBILITY IN LOW
STRATUS/LIGHT FOG. THERE IS LIKELY EVEN SOME OFF-AND-ON LIGHT
DRIZZLE ONGOING. IN SHORT...EXPECT A GRADUAL IMPROVEMENT IN
CEILING/VISIBILITY AS THE DAY WEARS ON...BUT SUB-VFR CONDITIONS
MAY LAST LONGER (ESPECIALLY CEILING-WISE) THAN EARLIER THOUGHT.
PRECIPITATION-WISE...THE FIRST 12-15 HOURS SHOULD MAINLY FEATURE
SPOTTY LIGHT SHOWERS/DRIZZLE...WITH A BETTER CHANCE OF ORGANIZED
THUNDERSTORM ACTIVITY ARRIVING THIS EVENING INTO TONIGHT. IN
CLOSING...ANTICIPATE AMENDMENTS TO BE NECESSARY DURING THE PERIOD
AS WE GRADUALLY GET A HANDLE ON SHORT-TERM TRENDS.
&&
.GID WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
KS...NONE.
&&
$$
SHORT TERM...JCB
LONG TERM...ROSSI
AVIATION...PFANNKUCH
AREA FORECAST DISCUSSION
NWS HASTINGS NE
548 AM CDT THU APR 16 2015
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 412 AM CDT THU APR 16 2015
RADAR SHOWS SHOWERS AND THUNDERSTORMS MOVING NORTH/NORTHEAST WITH
DEVELOPMENT ON THE SOUTH END OF THE MAIN CLUSTER OF THUNDERSTORMS.
SURFACE ANALYSIS SHOWS A LOW PRESSURE SYSTEM ACROSS WESTERN KANSAS
WITH A COLD FRONT EXTENDING TO THE NORTH ACROSS NEBRASKA.
AN UPPER LEVEL LOW IN THE IN THE FOUR CORNERS REGION WILL DRIFT
TOWARD THE EAST TODAY AND TONIGHT. IN ADVANCE OF THE UPPER LOW A FEW
WAVES WILL MOVE ACROSS THE AREA THROUGH TONIGHT. THE NAM AND GFS
BOTH SPREAD THE PRECIPITATION ACROSS THE FORECAST AREA THROUGH THE
MORNING HOURS AS THE FIRST OF THE WAVES MOVE THROUGH THE FORECAST
AREA. THE RAP AND THE 4KM WRF BOTH INDICATE THIS INITIAL GROUP OF
THUNDERSTORMS WILL MOVE THROUGH AND ALTHOUGH THERE MAY BE SOME
ISOLATED THUNDERSTORMS AROUND...THERE COULD BE A BREAK THIS MORNING.
HAVE KEPT POPS ACROSS THE AREA...BUT DID LOWER THEM A BIT THIS
MORNING.
THE NEXT WAVE WILL MOVE INTO THE AREA THIS AFTERNOON AND EVENING.
THUNDERSTORMS SHOULD DEVELOP IN WESTERN KANSAS AND SPREAD INTO THE
AREA DURING THE AFTERNOON. LATE AFTERNOON INTO THE EARLY EVENING THE
MUCAPE INCREASES TO NEARLY 2500 J/KG MAINLY ACROSS KANSAS. THIS IS
THE AREA WITH THE BEST CHANCE FOR SOME SEVERE WEATHER. ANOTHER UPPER
LEVEL WAVE PUSHES INTO THE AREA LATE TONIGHT. SHOWERS AND
THUNDERSTORMS ARE EXPECTED ACROSS THE AREA LATE TONIGHT.
.LONG TERM...(FRIDAY THROUGH WEDNESDAY)
ISSUED AT 412 AM CDT THU APR 16 2015
A PAIR OF UPPER LEVEL LOWS FORECAST TO TRACK ACROSS THE SOUTHERN
HALF OF THE COUNTRY WILL BRING SOME SIGNIFICANT CHANCES FOR
BENEFICIAL RAINFALL TO THE REGION OVER THE NEXT WEEK OR SO. THE
FIRST OF THESE LOW PRESSURE SYSTEMS IS CURRENTLY SPINNING ACROSS THE
DESERT SOUTHWEST...AND ALREADY HAVING AN IMPACT ON THE LOCAL
WEATHER. WITH THIS LOW CUT OFF FROM THE MAIN UPPER LEVEL FLOW ACROSS
CANADA...EXPECT VERY SLOW PROGRESSION TOWARDS THE EAST TO RESULT IN
MULTIPLE DAYS OF UNSETTLED WEATHER ACROSS THE REGION.
WITH MOIST SOUTHERLY FLOW AHEAD OF THIS SYSTEM...DEWPOINTS HAVE
SURGED INTO THE 50S ACROSS MUCH OF THE LOCAL AREA AND EXPECT THE
ASSOCIATED INSTABILITY TO HELP AID IN THE FORMATION OF THUNDERSTORMS
BOTH FRIDAY AND SATURDAY. THAT SAID...WITH MUCH BETTER SHEAR TO WORK
WITH ON FRIDAY AFTERNOON/EVENING...THIS APPEARS TO BE THE BEST SHOT
FOR MORE WIDESPREAD STRONG AND POTENTIALLY SEVERE STORMS ACROSS THE
REGION...AND NOT SURPRISINGLY ROUGHLY THE SOUTHERN HALF OF THE
FORECAST AREA IS NOW OUTLOOKED BY SPC. IF REALIZED...THE MAIN
HAZARDS ARE LIKELY TO BE LARGE HAIL AND STRONG WIND GUSTS.
WHILE STILL NOT OUT OF THE QUESTION FOR SATURDAY...ADDITIONAL STRONG
TO MARGINALLY SEVERE THUNDERSTORMS WILL BE POSSIBLE DURING THE
AFTERNOON AND EVENING HOURS...BUT DUE TO DIMINISHED SHEAR
VALUES...THINK THE COVERAGE OF THESE STRONGER STORMS WILL BE MUCH
MORE LIMITED. EVEN SO...WIDESPREAD BENEFICIAL RAINFALL IS
ANTICIPATED FOR THE ENTIRE REGION BOTH DAYS...WITH STORM TOTAL
PRECIPITATION AMOUNTS OVER 2 INCHES EXPECTED TO BE FAIRLY WIDESPREAD
BY THE TIME THE RAINFALL ENDS AND THE RESPONSIBLE LOW PRESSURE
SYSTEM TRACKS EASTWARDS SUNDAY AFTERNOON.
THIS LOW PRESSURE SYSTEM WILL BE SHIFTED EASTWARD BY A FAIRLY STRONG
COLD FRONT FORECAST TO DROP SOUTH ACROSS THE LOCAL AREA SUNDAY. THIS
COLD FRONT WILL BRING SIGNIFICANTLY COOLER TEMPERATURES TO START THE
NEW WORK WEEK WITH POTENTIALLY SOME NEAR FREEZING TEMPERATURES
CURRENTLY FORECAST FOR BOTH MONDAY AND TUESDAY MORNINGS. WHILE
ACTUAL FROST MAY NOT DEVELOP EITHER DAY...THESE COOLER TEMPERATURES
WILL BE SOMETHING TO MONITOR AS SENSITIVE VEGETATION MAY BE
IMPACTED. ADDITIONALLY...WITH STRONG NORTHWESTERLY WINDS BEHIND THIS
FRONT AND DRIER AIR ADVECTING IN FROM THE NORTH...COULD EVENTUALLY
SEE SOME NEAR CRITICAL FIRE WEATHER CONDITIONS REALIZED ACROSS
ROUGHLY THE NORTHWESTERN HALF OF THE LOCAL AREA. BECAUSE BOTH OF
THESE POTENTIAL HAZARDS ARE STILL SEVERAL DAYS OUT AND
MARGINAL...OPTED NOT TO MENTION EITHER OF THESE IN THE MORNING HWO.
THEREAFTER...RAINFALL CHANCES WILL INCREASE MIDWEEK AS ANOTHER UPPER
LEVEL LOW MOVES INTO THE DESERT SOUTHWEST AND MOISTURE INCREASES
ACROSS THE REGION.
&&
.AVIATION...(FOR THE 12Z KGRI/KEAR TAFS THROUGH 12Z FRIDAY MORNING)
ISSUED AT 546 AM CDT THU APR 16 2015
THUNDERSTORMS HAVE MOVED TO THE NORTH OF THE TERMINAL AREAS. THERE
COULD BE A SPRINKLE OR TWO FOR A WHILE BUT THEN THERE COULD BE A
BREAK. THUNDERSTORMS ARE EXPECTED TO REDEVELOP LATER THIS MORNING
OR EARLY THIS AFTERNOON.
&&
.GID WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
KS...NONE.
&&
$$
SHORT TERM...JCB
LONG TERM...ROSSI
AVIATION...JCB
AREA FORECAST DISCUSSION
NWS RALEIGH NC
1104 AM EDT THU APR 16 2015
.SYNOPSIS...CHILLY HIGH PRESSURE WILL EXTEND INTO THE CAROLINAS AND
VIRGINIA FROM THE NORTHEAST THROUGH TONIGHT. A WEAK AREA OF LOW
PRESSURE WILL DEVELOP OFF THE SOUTHEAST U.S. COAST TODAY AND DRIFT
NORTHEAST AND AWAY FROM THE REGION ON FRIDAY. WEAK HIGH PRESSURE
WILL EXTEND INTO THE AREA LATE FRIDAY INTO SATURDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 1100 AM THURSDAY...
VERY WELL DEFINED WEDGE FRONT ASSOCIATED WITH A HYBRID COLD AIR
DAMMING EVENT SHOWING UP NICELY IN OBSERVATIONS. TO THE
SOUTHEAST...A COASTAL LOW IS DEVELOPING OFF THE COAST OF SC AND
FURTHER ENHANCING THE WEDGE BOUNDARY. THIS WILL MAKE TEMPERATURE
FORECASTS VERY TRICKY TODAY AS A VERY STRONG GRADIENT WILL BE
PRESENT FROM WEST TO EAST WITH VERY COOL HIGHS IN THE WEST AND
POTENTIALLY QUITE A BIT WARMER HIGHS IN THE EAST. FOR NOW HAVE MID
50S IN THE WEST AND UPPER 60S IN THE EAST BUT BY LATE IN THE
AFTERNOON THIS COULD VERY WELL PAN OUT TO BE LOWER 50S IN THE WEST
AND LOWER TO MID 70S IN THE EASTERN TIER OF COUNTIES. PRECIPITATION
CONTINUES ACROSS THE CENTRAL PIEDMONT AND THE NORTHEASTERN COUNTIES
AIDED BY ISENTROPIC LIFT AND SOME UPPER LEVEL DIVERGENCE AS WE SIT
UNDER THE LEFT EXIT REGION OF A 250 MB JET. PRECIPITATION SHOULD
BEGIN TO TREND DOWNWARD HOWEVER AS ISENTROPIC LIFT WEAKENS AND SOME
VERY DRY MID-LEVEL AIR TO THE NORTHEAST TRIES TO WORK SOUTHWESTWARD
INTO THE CWA. THIS IS VERY EVIDENT ON THE SOUNDINGS WHERE THE KMHX
SOUNDING HAS A 5 DEGREE DEWPOINT DEPRESSION AT 850 MB AND THE KWAL
SOUNDING HAS A 33 DEGREE DEWPOINT DEPRESSION. AS PRECIPITATION MOVES
NORTHEAST...COMPOSITE RADAR SHOWS EVAPORATION OF THE
PRECIPITATION...MOST LIKELY CAUSED BY THE MID LEVEL DRY AIR. AS FAR
AS CONVECTIVE ALLOWING MODELS ARE CONCERNED...ONLY ONE REALLY HAS A
HANDLE OF THE CURRENT MODE OF PRECIP AND THAT IS THE HRRR WHICH
DEPICTS THE CURRENT PATTERN VERY WELL. GOING INTO THIS AFTERNOON THE
RAIN OVER THE CENTRAL PART OF THE CWA PUSHES NORTHEAST AND CHANCES
ELSEWHERE DIMINISH THROUGH THE AFTERNOON TO JUST A FEW PATCHES OF
DRIZZLE OR LIGHT RAIN BY THIS EVENING. CLOUDS SHOULD REMAIN
OVERNIGHT...THUS MODERATING LOWS...MAINLY LOW TO MIDDLE 50S NW TO SE.
&&
.SHORT TERM /FRIDAY AND FRIDAY NIGHT/...
AS OF 317 AM THURSDAY...
FRIDAY SHOULD SEE THE BEGINNING OF A SLOW IMPROVEMENT IN SKY
CONDITION AND TEMPS. DEVELOPING (THOUGH WEAK) NW FLOW IN THE MID-
UPPER LEVELS WILL BEGIN TO SCOUR THE CAD AIR MASS FROM ALOFT.
STILL...RESIDUAL LOW LEVEL MOISTURE WILL REMAIN HIGH ENOUGH TO
PRODUCE EXTENSIVE CLOUDINESS IN THE MORNING WITH SOME PARTIAL BREAKS
DEVELOPING IN THE AFTERNOON. THIS HEATING ALONG WITH THE PASSAGE OF
A WEAK MID LEVEL TROUGH MAY PROVIDE ENOUGH LIFT TO GENERATE AN
ISOLATED SHOWER OR THUNDERSTORM ACROSS CENTRAL NC. TEMPS WILL BEGIN
TO RECOVER FRIDAY THOUGH IF CLOUDS STICK AROUND A LOT LONGER THAN
EXPECTED...MAX TEMPS MAY END UP BEING 3-5 DEGREES COOLER THAN
CURRENTLY FORECAST...ESPECIALLY ACROSS THE NORTHERN PIEDMONT. MAX
TEMPS FRIDAY LOW-MID 70S.
FRIDAY NIGHT..PARTIAL CLEARING MAY LEAD TO THE DEVELOPMENT OF FOGGY
CONDITIONS AFTER MIDNIGHT. MIN TEMPS 55-60.
&&
.LONG TERM /SATURDAY THROUGH WEDNESDAY/...
AS OF 320 AM THURSDAY...
SATURDAY AND SATURDAY NIGHT: MID LEVEL S/W RIDGING WILL LARGELY KEEP
CENTRAL NC DRY ON SATURDAY AND SATURDAY NIGHT. HOWEVER... WITH AND
EASTERLY TO SOUTHEASTERLY SURFACE FLOW DEVELOPING LATE SATURDAY
ALONG WITH DAYTIME HEATING CANT COMPLETELY RULE OUT SOME AFTERNOON
SHOWERS AND STORMS ACROSS FAR EASTERN PORTIONS OF THE AREA WHERE LOW
LEVEL CONVERGENCE MAY BE ENHANCED SOME ALONG PERHAPS A SEABREEZE.
THUS... WILL GO WITH A SLIGHT CHANCE FOR SHOWERS AND STORMS ACROSS
OUR FAR EASTERN COUNTIES FOR SATURDAY AFTERNOON. WITH SKIES NOW
EXPECTED TO BE AT LEAST PARTLY SUNNY AT TIMES WILL RAISE HIGH TEMPS
A DEGREE OR TWO INTO THE UPPER 70S NW TO LOWER 80S SE.
THE LATEST GFS/ECMWF/NAM NOW SHOW THE ONSET OF PRECIP DELAYED A GOOD
6 TO 12 HOURS FROM PREVIOUS FORECASTS. THUS... WILL NOT INTRODUCE
POPS UNTIL CLOSE TO DAYBREAK... FIRST IN THE WEST THEN SPREADING
EAST THROUGH THE DAY ON SUNDAY. WITH INCREASING SOUTHERLY LOW LEVEL
FLOW AND CLOUD COVER ON SATURDAY NIGHT/EARLY SUNDAY MORNING EXPECT
LOW TEMPS WILL ABOVE NORMAL... GENERALLY RANGING FROM THE MID 50S IN
THE FAR NE (WHERE WE MAY SEE SOME CLEARING BRIEFLY WITH THE LOSS OF
HEATING AND PRIOR TO THE INCREASING OF MID AND HIGH LEVEL CLOUDS
COVER) TO GENERALLY NEAR 60 ELSEWHERE.
SUNDAY THROUGH MONDAY NIGHT: GOOD MOISTURE TRANSPORT IS EXPECTED ON
SUNDAY INTO SUNDAY NIGHT AS CLOSED LOW INVOF THE FOUR CORNERS REGION
(CURRENTLY) SHIFT EASTWARD AND OPENS WHILE COMBINING WITH A NORTHERN
STREAM TROUGH TO AMPLIFY THE MID/UPPER LEVEL FLOW ACROSS THE CENTRAL
AND EASTERN PART OF THE COUNTRY LATE WEEKEND INTO EARLY NEXT WEEK.
THIS WILL HELP TO DRIVE A LEAD DEEP MOIST AXIS THROUGH CENTRAL NC
LATE SUNDAY THROUGH EARLY MONDAY MORNING. WITH STRONG SOUTHERLY LOW
LEVEL FLOW WITH THIS SYSTEM AND EXCELLENT MOISTURE TRANSPORT WE
SHOULD SEE A LARGE BAND OF SHOWER/ISOLATED STORMS AND HEAVY RAIN
MOVE THROUGH CENTRAL NC LATE SUNDAY INTO SUNDAY NIGHT... WITH A MAIN
THREAT OF HEAVY RAIN. ALTHOUGH GIVEN THE STRONG LOW LEVEL WIND
FIELDS CAN COMPLETELY RULE OUT AT LEAST A STRONG WIND GUST OR TWO.
BUT GIVEN THE RATHER WEAK INSTABILITY AND POOR DIURNAL TIMING FOR
THE MOST PART ANY SEVERE THREAT SHOULD REMAIN LOW. HIGHS SHOULD BE
COOLER SUNDAY WITH THE INCREASE IN CLOUDS AND EVENTUALLY PRECIP LATE
IN THE DAY...EXPECT HIGHS TO BE IN THE MID TO UPPER 60S NW (WHERE WE
COULD SEE A BRIEF CAD AIRMASS DEVELOP) TO THE MID 70S SE/E (MAYBE
EVEN A FEW UPPER 70S SE). LOWS MONDAY MORNING SHOULD BE WARM FOR
THIS TIME OF YEAR... EXPECT LOWS IN THE LOWER TO MID 60S.
THE MAIN SURFACE COLD FRONT SHOULD MOVE THROUGH THE REGION LATE
MONDAY INTO MONDAY EVENING. WHILE THE STRONGER MID AND LOW LEVEL
FLOW WILL HAVE PUSHED TO THE EAST... WE SHOULD SEE INSTABILITY
INCREASE AS SOME DRIER MID LEVEL AIR WORKS INTO THE AREA FROM THE
SOUTHWEST ON MONDAY MORNING/AFTERNOON. THIS SHOULD HELP TO YIELD AT
LEAST SOME DESTABILIZATION AHEAD OF THE FRONT ON MONDAY RESULTING IN
ISOLATED TO SCATTERED SHOWER AND STORMS MONDAY AFTERNOON/EVENING IN
ADVANCE OF THE FRONT... WITH POSSIBLY A FEW STRONG TO MAYBE SEVERE
STORMS (AS DEEP LAYER SHEAR WILL STILL BE AROUND 25 TO 35 KTS). BEST
CHANCE OF ANY SVR AT THIS TIME (KEEP IN MIND WE ARE STILL A WAYS OUT
IN TIME) WOULD BE ACROSS EASTERN PORTIONS OF THE AREA. HIGHS MONDAY
ARE EXPECTED TO BE IN THE 70S TO LOWER 80S EAST/SOUTHEAST. LOWS
TUESDAY MORNING RANGING FROM THE MID 50S NW TO AROUND 60 SE.
TUESDAY THROUGH WEDNESDAY: DRIER WEATHER IS EXPECTED BEHIND THE
FRONT ON TUESDAY AND WEDNESDAY... WITH A MUCH DRIER AIRMASS
ADVECTING INTO THE REGION. HIGH TEMPS SHOULD BE NEAR NORMAL GENERALLY
IN THE 70S... WITH LOWS IN THE 40S AND 50S.
&&
.AVIATION /12Z THURSDAY THROUGH MONDAY/...
AS OF 747 AM THURSDAY...
AN UNSETTLED WEATHER PATTERN WILL CONTINUE ACROSS CENTRAL NC THROUGH
THE REMAINDER OF THE WORK WEEK. A BRIEF RESPITE FROM THE SUB VFR
CONDITIONS EXPECTED SATURDAY BEFORE A LOW PRESSURE SYSTEM AFFECTS
OUR REGION SUNDAY.
SFC HIGH PRESSURE WILL CONTINUE TO EXTEND ACROSS CENTRAL NC TODAY
THROUGH EARLY FRIDAY...KEEPING A COOL MOIST STABLE AIR MASS IN
PLACE. UPPER LEVEL DISTURBANCES TRAVERSING OVERHEAD WILL CAUSE
PERIODS OF PATCHY LIGH RAIN THROUGH THIS AFTERNOON.
THE FLOW ALOFT WILL BECOME MORE WESTERLY AND EVENTUALLY NWLY BY LATE
FRIDAY. MEANWHILE THE SFC RIDGE WILL WEAKEN. THIS WILL LEAD TO A
SLOW IMPROVEMENT IN AVIATION CONDITIONS THROUGH FRIDAY NIGHT. EXPECT
LOW END VFR/MVFR CEILINGS TO PERSIST THROUGH EARLY FRIDAY. PATCHES
OF LIGHT RAIN WILL OCCUR THROUGH EARLY AFTERNOON THEN DIMINISH.
AFTER SUNSET...CEILINGS WILL BECOME IFR OVER MOST OF THE AREA AND
REMAIN IFR UNTIL MID MORNING FRIDAY. MOST LOCATIONS SHOULD SEE VFR
CONDITIONS FRIDAY AFTERNOON...PERSISTING THROUGH SATURDAY.
A LOW PRESSURE SYSTEM WILL APPROACH FROM THE WEST LATE SATURDAY AND
AFFECT OUR REGION SUNDAY THROUGH EARLY MONDAY. THIS SYSTEM WILL
BRING A HIGH PROBABILITY OF SHOWERS AND SUB VFR CEILINGS.
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...WSS
NEAR TERM...ELLIS
SHORT TERM...WSS
LONG TERM...BSD
AVIATION...WSS
AREA FORECAST DISCUSSION
NWS GREEN BAY WI
606 AM CDT THU APR 16 2015
UPDATED AVIATION PORTION FOR 12Z TAF ISSUANCE
.SHORT TERM...TODAY...TONIGHT...AND FRIDAY
ISSUED AT 257 AM CDT THU APR 16 2015
THE LATEST RAP ANALYSIS AND SATELLITE/RADAR IMAGERY SHOW HIGH
PRESSURE CENTERED OVER THE EAST COAST...BUT WITH A RIDGE AXIS
EXTENDING WEST TO THE WESTERN GREAT LAKES. VERY DRY AIR CONTINUES TO
HOLD ON ACROSS THE REGION...AND DEWPOINTS HAVE STRUGGLED TO RECOVER
OVER CENTRAL AND NORTH-CENTRAL WISCONSIN OVERNIGHT. SOUTHEAST LOW
LEVEL FLOW OVER THE SOUTHERN GREAT LAKES IS SLOWLY VEERING TO MORE
OF A SOUTHERLY DIRECTION...BUT IS STILL TRYING TO PUSH LIGHT SHOWER
ACTIVITY ACROSS SOUTH-CENTRAL LAKE MICHIGAN. THIS IS AHEAD OF A
SHORTWAVE OVER THE IL/IN BORDER. THE BONE DRY AIRMASS AND VEERING
FLOW IS NOT HELPING THESE SHOWERS TO MAKE A WESTWARD JAUNT...AND THE
LATEST MESOMODELS KEEP THESE SHOWERS EAST OF THE MANITOWOC SHORELINE
EARLY THIS MORNING. THIS SHOWER ACTIVITY ALONG WITH FIRE WEATHER
CONDITIONS ARE THE MAIN FORECAST CONCERNS IN THE SHORT TERM.
TODAY...THE SHORTWAVE OVER THE IL/IN BORDER WILL LIFT NE THIS
MORNING AND THEN EAST THIS AFTERNOON AS RIDGING OVER THE GREAT LAKES
FLATTENS. 850MB FLOW WILL CONTINUE TO VERY GRADUALLY VEER THIS
MORNING WHICH COMBINED WITH THE VERY DRY AIR ACROSS THE REGION WILL
GIVE THE LIGHT SHOWER ACTIVITY OVER SOUTHERN LAKE MICHIGAN A SUBTLE
PUSH TO THE EAST. SO WILL KEEP THE DRY FORECAST IN TACT...BUT WILL
INCREASE CLOUD COVER OVER EAST-CENTRAL WISCONSIN TODAY AS 5K-6KFT
CLOUDS OVER NORTHERN ILLINOIS WILL LIKELY ARRIVE THIS MORNING.
ELSEWHERE...A MID-LEVEL DECK OVER MINNESOTA AND IOWA WILL SHIFT TO
THE EAST AND MOVE INTO NORTH-CENTRAL WISCONSIN DURING THE
AFTERNOON. UNTIL THESE CLOUDS ARRIVE...A POCKET OF VERY DRY AIR
WILL REMAIN IN PLACE ACROSS CENTRAL AND NORTH-CENTRAL WISCONSIN.
MIXING WILL NOT BE AS GOOD TODAY DUE TO LIGHTER WINDS ALOFT...BUT
STILL LOWERED DEWPOINTS SINCE THINK WILL STILL BE ABLE TO TAP INTO
SOME OF THE BONE DRY AIR JUST ABOVE THE INVERSION. AS A
RESULT...HAVE DROPPED DEWPOINTS AND HUMIDITIES OVER CENTRAL AND
NORTH-CENTRAL WISCONSIN THIS AFTERNOON. HUMIDITIES COULD FALL
BETWEEN 20-25 PCT. FORTUNATELY...WINDS WILL BE MUCH LIGHTER
TODAY...SO SHOULD NOT SEE A REPEAT OF THE CRITICAL FIRE WEATHER
CONDITIONS. HIGHS MAINLY IN THE MID TO UPPER 60S AWAY FROM LAKE
MICHIGAN.
TONIGHT...A COLD FRONT WILL DECAY AS IT MOVES INTO NORTH-CENTRAL
WISCONSIN LATE. MID-LEVEL CLOUDS WILL CONTINUE TO SPREAD EAST AHEAD
OF THE FRONT...BUT GRADUALLY DISSIPATE IN THE PROCESS. SHOULD
THEREFORE SEE A PARTLY CLOUDY TO MOSTLY CLEAR NIGHT. WITH THE
THINNING CLOUDS...DO NOT THINK THERE WILL BE A DEEP ENOUGH CLOUD
LAYER FOR SPRINKLES OR LIGHT SHOWERS. LOWS MAINLY IN THE LOW TO MID
40S.
FRIDAY...THE FRONT WILL WASH OUT ACROSS NORTHERN WISCONSIN. MAY SEE
SOME CU DEVELOP OVER CENTRAL AND EAST-CENTRAL WISCONSIN DURING THE
AFTERNOON...BUT THE NORTH SHOULD SEE AN INFLUX OF DRY AIR...THAT
WILL DROP HUMIDITIES NEAR 25 PCT IN THE AFTERNOON. HIGHS WILL BE
WARMER THAN TODAYS READINGS...AND RAISED THEM INTO THE UPPER 60S
NORTH TO MID 70S SOUTH.
.LONG TERM...FRIDAY NIGHT THROUGH WEDNESDAY
ISSUED AT 257 AM CDT THU APR 16 2015
DRY CONDITIONS WILL CONTINUE FRIDAY NIGHT AND SATURDAY AS CANADIAN
HIGH PRESSURE BUILDS INTO THE STATE. NORTHWEST WINDS WILL TURN
TO THE EAST AND NORTHEAST LATE FRIDAY NIGHT AND SATURDAY. SATURDAY
AFTERNOON WILL AGAIN FEATURE VERY LOW AFTERNOON RELATIVE HUMIDITY
READINGS AWAY FROM THE LAKE...WITH READINGS DROPPING INTO THE 20
TO 40 PERCENT RANGE WITH THE LOWEST READINGS NORTH AND WEST OF THE
FOX VALLEY.
MEANWHILE...CLOSED UPPER LOW ACROSS THE CENTRAL PLAINS IS EXPECTED
TO OPEN UP AS 500MB TROUGH ACROSS SOUTHERN CANADA WILL BEGIN TO
LIFT THE SOUTHERN SYSTEM NORTHEAST TOWARDS THE REGION. QUIET A
SPREAD IN THE MODELS ON HOW QUICK THE RAIN WILL ARRIVE OVER THE
WEEKEND. THE WRF MODELS WAS QUICKEST...ALREADY BRINGING RAIN ON
SATURDAY TO PORTIONS OF THE AREA. THE GFS MODEL WAS IN THE MIDDLE
OF THE ROAD SOLUTION...WHILE THE CANADIAN/ECMWF MODEL WERE THE SLOWEST
SOLUTION WITH RAIN ARRIVING ON SUNDAY. TRENDED TOWARD THE SLOWER
SOLUTION FOR THE MEANTIME DUE TO BETTER CONSISTENCY FROM RUN TO
RUN. DID ADD A SMALL CHANCE OF RAIN ACROSS THE WEST LATE SATURDAY
NIGHT...AND THEN BOOSTED RAIN CHANCES INTO THE LIKELY CATEGORY ON
SUNDAY. DID RAISE RAIN CHANCES SUNDAY NIGHT AS WELL. THE 500MB
SYSTEMS WILL MERGE INTO A CLOSED UPPER LOW ACROSS THE UPPER
MIDWEST AND WESTERN GREAT LAKES REGION EARLY NEXT WEEK. THIS
WOULD SUPPORT A COOLER AND UNSETTLED PATTERN ACROSS THE REGION
ON MONDAY THROUGH WEDNESDAY. HAVE CHANCES OF SHOWERS EACH PERIOD...
ALONG WITH A LITTLE SNOW LATE AT NIGHT INTO THE EARLY MORNING
HOURS ON TUESDAY AND WEDNESDAY. IT IS WISCONSIN! TEMPERATURES
BY EARLY NEXT WEEK WILL RUN WELL BELOW NORMAL.
&&
.AVIATION...FOR 12Z TAF ISSUANCE
ISSUED AT 605 AM CDT THU APR 16 2015
VFR CONDITIONS EXPECTED TODAY AND TONIGHT. SCATTERED LIGHT SHOWERS OVER
LAKE MICHIGAN WILL APPROACH MTW THIS MORNING...BUT GUIDANCE KEEPS
THIS SHOWER ACTIVITY JUST OFFSHORE. WILL CONTINUE TO MONITOR.
OTHERWISE...A BROKEN 6KFT CLOUD DECK WILL MOVE INTO EAST-CENTRAL
WISCONSIN THIS MORNING BEFORE DEPARTING EARLY IN THE AFTERNOON.
THEN SCT TO BKN MID CLOUDS WILL MOVE ACROSS THE REGION FROM WEST
TO EAST LATE THIS AFTERNOON INTO TONIGHT. NO PRECIPITATION IS
EXPECTED.
&&
.GRB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM.....MPC
LONG TERM......ECKBERG
AVIATION.......MPC
AREA FORECAST DISCUSSION
NWS CHEYENNE WY
435 AM MDT THU APR 16 2015
.SHORT TERM...(TODAY THROUGH FRIDAY NIGHT)
ISSUED AT 435 AM MDT THU APR 16 2015
SIGNIFICANT STORM STILL EXPECTED TO IMPACT THE HIGHER ELEVATIONS
FROM LATE THIS AFTERNOON THROUGH MIDDAY FRIDAY. WATER VAPOR
IMAGERY SHOWS THE CLOSED UPPER LOW SPINNING JUST WEST OF THE FOUR
CORNERS REGION. WE ARE GETTING A BREAK IN THE PRECIP...HOWEVER
THIS WILL LIKELY BE SHORT LIVED (ONLY THROUGH THIS MORNING) AS
CLOUD TOPS ARE COOLING IN COLORADO. THE MODELS CONTINUE TO
INDICATE EXCELLENT LARGE SCALE LIFT DEVELOPING IN AREAS ALONG THE
COLORADO BORDER BY LATE THIS AFTN. UPWARD VERTICAL MOTION IS
MAXIMIZED FROM 21Z THIS AFTN THROUGH 12Z FRI IN THE SOUTHERN HALF
OF THE CWA. THIS IS DUE TO EXCELLENT UPPER LEVEL DIFFLUENCE AND
ISENTROPIC LIFT. WHILE WIDESPREAD SUBSTANTIAL QPF AMOUNTS ARE
VERY LIKELY...THE TRICKIER PART OF THIS FCST INVOLVED THE SNOW
LEVEL AND ASSOCIATED SNOW ACCUMULATIONS.
THE 00Z GUIDANCE CAME IN A BIT WARMER THAN YESTERDAY WITH RESPECT
TO SFC TEMPS FROM LATE THIS AFTN THROUGH FRIDAY MORNING. WARM AIR
ADVECTION IS OCCURRING AS 700MB TEMPS AT CHEYENNE RISE FROM -4C
THIS MORNING TO -1C BY FRI MORNING. THE CYS SOUNDING FROM BOTH THE
NAM AND GFS SHOW SFC TEMPS OF 2-3C WITH COMPLETE SATURATION
THROUGH TONIGHT. THUS...DESPITE THE STRONG LLVL LIFT...THINKING
IS THAT A MIX OF RAIN/SNOW OR ALL RAIN WILL OCCUR BETWEEN
ELEVATIONS OF 6250-5500 FT WITH THIS EVENT. DECIDED TO CANCEL THE
WINTER STORM WATCH FOR CENTRAL LARAMIE COUNTY AND EAST PLATTE
COUNTY WITH THIS REASONING...AND WILL LET DAY SHIFT SEE IF THE 12Z
GUIDANCE COMES IN ANY COOLER OR IF ANY DRIER AIR COULD CAUSE SOME
WET-BULBING. THE PRECIP WILL START OUT AS ALL SNOW AT ELEVATIONS
ABOVE 6500 FT THIS AFTN AND EARLY EVENING...WITH THE SNOW LEVEL
POSSIBLY RISING TO AROUND 7500 FT BY FRI MORNING. THE WINTER STORM
WATCH WAS UPGRADED TO A WARNING FROM JUST WEST OF CHEYENNE TO
ARLINGTON AND ALSO FOR THE SNOWY RANGE. WHILE TRAVEL WILL BE
AFFECTED ALONG INTERSTATE 80 FROM CHEYENNE TO ARLINGTON...THE
BIGGEST IMPACTS WILL LIKELY BE OVER THE FROM BUFORD TO THE
INTERSTATE 80 SUMMIT WHERE UP TO A FOOT OF SNOW IS FCSTED.
BY FRI AFTN THE UPPER LOW WILL HAVE MOVED INTO CENTRAL COLORADO.
THE MODELS SHOW VERY GOOD LIFT AND WIDESPREAD PRECIP ACROSS THE
CWA THROUGH THE AFTN. DECIDED TO END THE WINTER STORM HIGHLIGHTS
AT 18Z FRI AS SFC TEMPS WILL LIKELY BE ABOVE FREEZING ACROSS ALL
ZONES EXPECT MAYBE THE HIGHER ELEVATIONS OF THE SNOWY RANGE. THE
BAND OF PRECIP IS PROGGED TO SHIFT NORTHWARD FROM NORTHERN CARBON
TO THE NORTHERN NEBRASKA PANHANDLE BY FRI EVENING. IT IS AT THIS
TIME THAT DRIER AIR WILL WORK INTO THE SOUTHERN HALF OF THE CWA
AND PRECIP WILL DIMINISH. WITH MOST OF THE MODELS INDICATING QPF
AMOUNTS OF 1.25-2.0 INCHES FROM THIS AFTERNOON THROUGH FRIDAY
NIGHT FOR AREAS ALONG AND EAST OF THE LARAMIE RANGE...CONFIDENCE
IS HIGH THAT THIS SYSTEM WILL BRING WELL NEEDED MOISTURE TO THE
REGION.
.LONG TERM...(SATURDAY THROUGH WEDNESDAY)
ISSUED AT 435 AM MDT THU APR 16 2015
A COOL AND SHOWERY PERIOD STILL EXPECTED ACROSS THE CWFA THIS
WEEKEND AND EARLY NEXT WEEK AS NORTHWEST FLOW PREVAILS. REMNANTS
OF THE UPPER LOW THAT WILL HAVE WOBBLED AROUND COLORADO FOR THE
BETTER PART OF 3 DAYS LATE THIS WEEK...WILL CARRY LINGERING
IMPACTS ACROSS THE REGION EVEN INTO SATURDAY. 00Z MEDIUM RANGE
GUIDANCE ARE CONSISTENT IN PINWHEELING A FINAL VORT LOBE SOUTH TO
NORTH THRU THE AREA ON SATURDAY. MODELS TARGET WRN AND NRN ZONES
WITH THE BEST AXIS OF PRECIP ON SATURDAY...THOUGH COOL MID-LEVEL
TEMPS WILL BE ENOUGH TO PRODUCE THE POSSIBILITY OF SHOWERS
EVERYWHERE. FINALLY...THE UPPER-LOW WILL FULLY PHASE INTO THE NRN
STREAM BY SUNDAY. 00Z MODELS HAVE TRENDED DEEPER/STRONGER WITH
KICKER SYSTEM HOWEVER. THIS WILL RE-ENFORCE PRECIP CHANCES FOR
SUNDAY. IT LOOKS SOMEWHAT DRIER MON-TUE...THOUGH STILL CANT
COMPLETELY RULE OUT SOME LIGHT SHOWER ACTIVITY ESPECIALLY IN AND
AROUND THE HIER TERRAIN. ANOTHER WEAK SHORTWAVE MAY BRING ADDL
SHOWER CHANCES TO THE AREA WED-THU. NONE OF THESE SHOWER CHANCES
WILL AMOUNT TO MUCH THO. TEMPS WILL BE THE COOLEST THIS WEEKEND
WITH HIGHS ONLY REACHING THE UPPER 40S TO NR 50 IN AND AROUND THE
MOUNTAINS WITH 50S TO NR 60 OUT ON THE ERN PLAINS. THESE SHOULD
WARM BACK INTO THE 50S AND MID 60S MON-WED.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z THURSDAY NIGHT)
ISSUED AT 1034 PM MDT WED APR 15 2015
LATEST HRRR GUIDANCE USED FOR THE 06Z TAFS. WIDESPREAD IFR/LIFR
WITH NORTHEAST UPSLOPING FLOW. PRECIP BECOMES WIDESPREAD THURSDAY
AFTERNOON...WITH A POSSIBLE HEAVY SNOW EVENT THURSDAY NIGHT INTO
FRIDAY MORNING FOR SOUTHEAST WYOMING AND A WIDESPREAD MODERATE
RAIN EVENT FOR THE PANHANDLE AIRPORTS.
&&
.FIRE WEATHER...
ISSUED AT 347 AM MDT THU APR 16 2015
NO FIRE WEATHER CONCERNS THROUGH THE WEEKEND. A COOL AND VERY WET
PATTERN WILL BE IN PLACE THROUGH FRIDAY. WIDESPREAD RAIN ACROSS
THE LOWER ELEVATIONS AND SNOW IN THE MOUNTAINS WILL OCCUR.
&&
.CYS WATCHES/WARNINGS/ADVISORIES...
WY...WINTER STORM WARNING FROM 3 PM THIS AFTERNOON TO NOON MDT FRIDAY
FOR WYZ114>117.
WINTER WEATHER ADVISORY FROM 3 PM THIS AFTERNOON TO NOON MDT
FRIDAY FOR WYZ103-105-106-110-112.
NE...NONE.
&&
$$
SHORT TERM...ZF
LONG TERM...CAH
AVIATION...GCC
FIRE WEATHER...ZF
AREA FORECAST DISCUSSION
NWS PUEBLO CO
424 PM MDT THU APR 16 2015
.UPDATE...
ISSUED AT 423 PM MDT THU APR 16 2015
UPDATED THE FORECAST TO CANCEL THE RED FLAG FOR THE SAN LUIS
VALLEY. SCATTERED SHOWERS ARE OVER THE VALLEY AND HUMIDITY IS
NO LONGER CRITICAL. ROSE
&&
.SHORT TERM...(THIS EVENING THROUGH FRIDAY)
ISSUED AT 356 PM MDT THU APR 16 2015
...MODERATE TO HEAVY SNOW POSSIBLE FOR THE MOUNTAINS TONIGHT AND
FRIDAY...
...CRITICAL FIRE WEATHER CONDITIONS POSSIBLE FOR THE FAR SOUTHEAST
PLAINS AGAIN ON FRIDAY THOUGH THIS IS DEPENDENT ON HOW MUCH RAIN
FALLS OVER THESE AREAS TONIGHT...
...MARGINAL POTENTIAL FOR SEVERE POSSIBLE FOR NORTHERN EL PASO AND
KIOWA COUNTIES ON FRIDAY...
STILL A HIGHLY DYNAMIC FORECAST AS MODELS HONE IN ON TRACK AND
STRENGTH OF THE CLOSED LOW CURRENTLY ACROSS THE 4 CORNERS REGION.
MODELS BOBBLE THE UPPER LOW SOUTHWARD A BIT THIS EVENING...THEN BACK
TO THE NORTHEAST ACROSS THE CO/NM BORDER TONIGHT AS ENERGY ROTATES
AROUND THE BASE OF THE UPPER LOW AND ACROSS CO. THEN IT MAKES
STEADIER PROGRESS TO THE NORTHEAST INTO EAST CENTRAL CO ON FRIDAY.
ALREADY SEEING ENHANCEMENT ACROSS THE SOUTHEAST MTS AND NRN NM AS
THE NEXT IMPULSE APPROACHES. HRRR SEEMS TO HAVE PICKED UP ON THIS
TREND FAIRLY WELL. WE SHOULD CONTINUE TO SEE SHOWERS FILL IN ACROSS
THE SOUTHEAST MOUNTAINS...AND I-25 CORRIDOR...WITH SNOW LEVELS
AROUND 6000-6500 FEET. SNOW LEVELS MAY ACTUALLY RISE A BIT FOR THE
LOWER EASTERN SLOPES AS STRONG WAA OCCURS OVERNIGHT...WHICH COULD
CAUSE A SWITCH BACK TO RAIN AT KCOS OVERNIGHT. HOWEVER...MTN AREAS
SHOULD CONTINUE TO SEE SNOW AND HAVE EXPANDED ADVISORIES ACROSS MUCH
OF THE MOUNTAIN AREAS. GIVEN THE CONVECTIVE POTENTIAL WITH THIS
EVENINGS ROUND...CONCERNED THAT PORTIONS OF TELLER COUNTY COULD HIT
WARNING CRITERIA...THOUGH DON`T THINK IT WILL BE WIDESPREAD ENOUGH
ACROSS THE ZONE TO WARRANT AN UPGRADE. CENTRAL LAKE COUNTY COULD BE
IN A SIMILAR BOAT...SO THESE AREAS WILL BE THE ONES TO WATCH
CLOSELY. MEANWHILE...MODELS SHOW DEFORMATION BAND SNOW SPREADING
WESTWARD INTO THE SOUTHWEST MOUNTAINS TONIGHT AND CONTINUING THROUGH
FRIDAY. HAVE OPTED TO EXPAND ADVISORIES INTO THE LA GARITAS WHERE
SNOW AMOUNTS ARE APPROACHING THE 6-12 INCH RANGE. STILL SOME
QUESTION OVER THE EASTERN SAN JUANS THOUGH...COULD SEE A COUPLE
INCHES FALL THERE TONIGHT...WITH ANOTHER 1-3 INCHES FALLING ON
FRIDAY AS THE UPPER LOW WRAPS DEFORMATION BAND BACK TO THE SOUTHWEST
ACROSS THE REGION. CONTEMPLATED AN ADVISORY FOR THIS REGION...BUT
AM COMING UP SHY OF THE 6-12 INCHES NEEDED FOR A WINTER WX
ADVISORY...THOUGH CERTAINLY SUBTLE CHANGES IN THE TRACK AND STRENGTH
OF THE LOW COULD RESULT IN HEAVIER AMOUNTS FOR THIS REGION.
STICKING TRUE TO THE GRIDS FOR NOW AND WILL LET LATER SHIFTS
REASSESS.
AS FOR SEVERE THUNDERSTORM POTENTIAL ACROSS THE PLAINS...APPEARS
TIMING OF THE INITIAL WAVE THIS AFTERNOON WAS TOO QUICK FOR THE LOW
LEVEL MOISTURE RETURN...AND NICE LINE OF THUNDERSTORMS HAS ALREADY
DEVELOPED AND PUSHED EASTWARD INTO KANSAS. HOWEVER AS SURFACE WINDS
HAVE VEERED MORE EASTERLY DUE TO FALLING SFC PRESSURES ACROSS NEW
MEXICO...40S AND LOWER 50 DEW POINTS HAVE PULLED WESTWARD INTO THE
FAR SOUTHEAST PLAINS. ACTIVITY INCREASING ACROSS NORTHERN NEW
MEXICO MAY STILL HAVE A CHANCE TO INTERACT WITH THIS MOISTURE TO
PRODUCE SOME ISOLATED SEVERE THUNDERSTORMS...WITH HAIL AND GUSTY
WINDS THE PRIMARY STORM THREATS. OVERNIGHT...LATEST HRRR HINTS AT
ANOTHER ROUND CLIPPING BY BACA COUNTY DURING THE 8Z TO 09Z
TIMEFRAME...AND EVEN SOME SPOTTY THUNDERSTORMS POSSIBLE AS FAR WEST
AS THE I-25 CORRIDOR. SO THOUGH MAIN THREAT FOR SEVERE
THUNDERSTORMS WILL BE THIS EVENING...CAN`T RULE OUT A LOW GRADE
SEVERE THREAT ACROSS THE FAR SOUTHEAST PLAINS EVEN DURING THE
OVERNIGHT HOURS...THOUGH THUNDERSTORMS WILL TEND TO BE MORE
ELEVATED. TOMORROW AS THE SURFACE LOW LIFTS INTO SOUTHEAST
CO...COULD SEE SOME ISOLATED THUNDERSTORMS EVEN IN THE MORNING...AND
LAPSE RATES WILL BE STEEP GIVEN THE MID LEVEL COOLING ASSOCIATED
WITH THE SURFACE LOW. NAM12 SHOWS UP TO 1000 J/KG OF CAPE ACROSS
NORTHERN PORTIONS OF THE SE PLAINS DURING THE MORNING...SO COULD
HAVE ANOTHER CHANCE FOR SEVERE THUNDERSTORMS ON FRIDAY. BY
AFTERNOON...DRY AIR SPREADS INTO THE SOUTHEAST PLAINS AS SURFACE LOW
LIFTS NORTHWARD. THIS PUTS THE AXIS OF BEST INSTABILITY ALONG THE
NORTHERN FRINGES OF THE SOUTHEAST PLAINS BY AFTERNOON...PRIMARILY
NORTHEAST EL PASO AND KIOWA COUNTIES. THESE AREAS ARE OUTLOOKED FOR
A MARGINAL SEVERE THREAT TOMORROW...AND THIS LOOKS ON TARGET. COULD
SEE THIS MARGINAL THREAT SLIPPING SOUTHWARD A BIT TO ACCOUNT FOR ANY
STRONG MORNING CONVECTION. BUT AS DRY AIR EXPANDS NORTHWARD...SO
DOES THE POTENTIAL FOR CRITICAL FIRE WEATHER PARAMETERS...ESPECIALLY
ACROSS LAS ANIMAS...BACA...BENT...PROWERS... AND OTERO COUNTIES.
THE MITIGATING FACTOR WILL BE THE POTENTIAL FOR RAINFALL TO WET
FUELS TONIGHT OVER THESE SAME ZONES. GIVEN THIS POTENTIAL...HAVE
NOT GONE OUT WITH A FIRE WEATHER WATCH...BUT IF PRECIPITATION
DOESN`T MATERIALIZE ACROSS A WIDESPREAD ENOUGH AREA ACROSS THESE
REGION...THEN LATER SHIFTS MAY NEED TO HOIST A RED FLAG WARNING. -KT
.LONG TERM...(FRIDAY NIGHT THROUGH THURSDAY)
ISSUED AT 356 PM MDT THU APR 16 2015
FRIDAY NIGHT THROUGH SATURDAY...MODELS HAVE SHIFTED A BIT OVER THE
PST 24 HRS...BUT STILL REMAIN FAIRLY CONSISTENT WITH THE PLACEMENT
AND PATH OF THE UPPER LOW. FRIDAY NIGHT THE LOW PRESSURE SYSTEM IS
FORECAST TO BE CENTERED RIGHT OVER COLORADO...THEN OVER THE NEXT 24
HRS IT WILL WOBBLE A BIT BEFORE SLOWLY EXITING THE STATE VIA THE
EASTERN BORDER. THIS PATTERN WOULD IMPLY THAT THE MTS...ESPECIALLY
THE CONTDVD...WILL GET THE BRUNT OF SNOWFALL...MAINLY THROUGH FRIDAY
NIGHT. THEREFORE...ONGOING WINTER HIGHLIGHTS RUNNING THROUGH 12Z
SATURDAY LOOK REASONABLE. SNOW AMOUNTS WILL THEN TAPER OVER OVER THE
DAY SATURDAY AS TEMPS BEGIN TO WARM AND THE SYSTEM WEAKENS. ISOLATED
TO SCATTERED SHOWERS ARE FORECAST FOR THE REMAINDER OF THE LOWER
ELEVATIONS...AND TEMPS DO NOT LOOK PARTICULARLY COLD WITH MIN TEMPS
IN THE 30S TO AROUND 40 F FOR THE PLAINS...AND MAX TEMPS SATURDAY IN
THE MID 50S TO LOWER 60S.
SUNDAY AND MONDAY...THE UPPER SYSTEM WEAKENS AND EXITS TO THE EAST
LATE SATURDAY...WITH BRISK NW FLOW ALOFT THEN SETTLING IN ACROSS THE
STATE. A COUPLE OF UPPER SHORTWAVES ARE EXPECTED TO DROP DOWN ACROSS
THE STATE ON BOTH DAYS...KEEPING THE THREAT OF SHOWER ACTIVITY FOR
THE CWA IN PLACE. LOOK FOR SCATTERED SHOWERS OVER THE HIGHER
TERRAIN...AND ISOLATED SHOWERS FOR THE PLAINS...WITH MAX TEMPS BOTH
DAYS HOVERING IN THE 50S TO NEAR 60 F.
TUESDAY THROUGH THURSDAY...CONFIDENCE IS FAIRLY LOW FOR WHAT HAPPENS
BEYOND MONDAY...THOUGH LONG RANGE MODELS SEEM TO AGREE ON THE
QUESTION MARK. A TEMPORARY RIDGE BUILDS INTO THE DESERT SW STARTING
TUE...HELPING TO LOWERING PCPN CHANCES AS WELL AS BOOSTING MAX TEMPS
FOR THE PLAINS BACK INTO THE 70S. TWO SEPARATE UPPER CLOSED LOW
SYSTEMS APPROACH STARTING WED NIGHT...ONE OVER THE PAC NW AND THE
OTHER OVER S CA...BUT THIS PATTERN WILL MOST LIKELY GO THROUGH
MULTIPLE ADJUSTMENTS BEFORE THEN. MOORE
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z FRIDAY EVENING)
ISSUED AT 356 PM MDT THU APR 16 2015
CURRENTLY...VFR TO MVFR CONDITIONS FOR THE THREE MAIN TAF SITES OF
KCOS...KPUB AND KALS AS WELL AS FOR MUCH OF THE LOWER ELEVATIONS.
FOR ELEVATIONS ABOVE ROUGHLY 7000 FT...IFR CONDITIONS PREVAILED
DUE TO EXTENSIVE LOWER CLOUD COVER AND ONGOING SNOW SHOWERS.
THE UPPER LOW WILL SLOWLY MOVE FROM THE SW QUAD TO THE CENTRAL
PORTIONS OF THE STATE OVER THE NEXT 24 HRS...BRINGING WAVES OF
RAIN/SNOW SHOWERS TO THE LOWER ELEVATIONS AND SNOW...HEAVY AT
TIMES...TO THE MTS. EXPECT MVFR CONDITIONS FOR KPUB AND KALS OVER
THE NEXT 24 HRS. KCOS IS EXPECTED TO DIP INTO IFR CONDITIONS THIS
EVENING...THEN BRIEFLY DROP DOWN INTO LIFR AFTER 11Z TOMORROW
MORN. CONDITIONS ACROSS THE HIGHER TERRAIN AND MT PASSES WILL
REMAIN IFR TO LIFR. MOORE
&&
.PUB WATCHES/WARNINGS/ADVISORIES...
WINTER WEATHER ADVISORY UNTIL 6 AM MDT SATURDAY FOR COZ059-062-
063-074-075.
WINTER WEATHER ADVISORY UNTIL 6 PM MDT FRIDAY FOR COZ076>079.
WINTER STORM WARNING UNTIL 6 AM MDT SATURDAY FOR COZ058-060-061-
072-073-080-082.
WINTER WEATHER ADVISORY UNTIL MIDNIGHT MDT FRIDAY NIGHT FOR
COZ066.
WINTER WEATHER ADVISORY UNTIL MIDNIGHT MDT FRIDAY NIGHT FOR
COZ081.
WINTER WEATHER ADVISORY UNTIL 6 PM MDT FRIDAY FOR COZ084.
&&
$$
UPDATE...ROSE
SHORT TERM...KT
LONG TERM...MOORE
AVIATION...MOORE
AREA FORECAST DISCUSSION
NWS PUEBLO CO
357 PM MDT THU APR 16 2015
.SHORT TERM...(THIS EVENING THROUGH FRIDAY)
ISSUED AT 356 PM MDT THU APR 16 2015
...MODERATE TO HEAVY SNOW POSSIBLE FOR THE MOUNTAINS TONIGHT AND
FRIDAY...
...CRITICAL FIRE WEATHER CONDITIONS POSSIBLE FOR THE FAR SOUTHEAST
PLAINS AGAIN ON FRIDAY THOUGH THIS IS DEPENDENT ON HOW MUCH RAIN
FALLS OVER THESE AREAS TONIGHT...
...MARGINAL POTENTIAL FOR SEVERE POSSIBLE FOR NORTHERN EL PASO AND
KIOWA COUNTIES ON FRIDAY...
STILL A HIGHLY DYNAMIC FORECAST AS MODELS HONE IN ON TRACK AND
STRENGTH OF THE CLOSED LOW CURRENTLY ACROSS THE 4 CORNERS REGION.
MODELS BOBBLE THE UPPER LOW SOUTHWARD A BIT THIS EVENING...THEN BACK
TO THE NORTHEAST ACROSS THE CO/NM BORDER TONIGHT AS ENERGY ROTATES
AROUND THE BASE OF THE UPPER LOW AND ACROSS CO. THEN IT MAKES
STEADIER PROGRESS TO THE NORTHEAST INTO EAST CENTRAL CO ON FRIDAY.
ALREADY SEEING ENHANCEMENT ACROSS THE SOUTHEAST MTS AND NRN NM AS
THE NEXT IMPULSE APPROACHES. HRRR SEEMS TO HAVE PICKED UP ON THIS
TREND FAIRLY WELL. WE SHOULD CONTINUE TO SEE SHOWERS FILL IN ACROSS
THE SOUTHEAST MOUNTAINS...AND I-25 CORRIDOR...WITH SNOW LEVELS
AROUND 6000-6500 FEET. SNOW LEVELS MAY ACTUALLY RISE A BIT FOR THE
LOWER EASTERN SLOPES AS STRONG WAA OCCURS OVERNIGHT...WHICH COULD
CAUSE A SWITCH BACK TO RAIN AT KCOS OVERNIGHT. HOWEVER...MTN AREAS
SHOULD CONTINUE TO SEE SNOW AND HAVE EXPANDED ADVISORIES ACROSS MUCH
OF THE MOUNTAIN AREAS. GIVEN THE CONVECTIVE POTENTIAL WITH THIS
EVENINGS ROUND...CONCERNED THAT PORTIONS OF TELLER COUNTY COULD HIT
WARNING CRITERIA...THOUGH DON`T THINK IT WILL BE WIDESPREAD ENOUGH
ACROSS THE ZONE TO WARRANT AN UPGRADE. CENTRAL LAKE COUNTY COULD BE
IN A SIMILAR BOAT...SO THESE AREAS WILL BE THE ONES TO WATCH
CLOSELY. MEANWHILE...MODELS SHOW DEFORMATION BAND SNOW SPREADING
WESTWARD INTO THE SOUTHWEST MOUNTAINS TONIGHT AND CONTINUING THROUGH
FRIDAY. HAVE OPTED TO EXPAND ADVISORIES INTO THE LA GARITAS WHERE
SNOW AMOUNTS ARE APPROACHING THE 6-12 INCH RANGE. STILL SOME
QUESTION OVER THE EASTERN SAN JUANS THOUGH...COULD SEE A COUPLE
INCHES FALL THERE TONIGHT...WITH ANOTHER 1-3 INCHES FALLING ON
FRIDAY AS THE UPPER LOW WRAPS DEFORMATION BAND BACK TO THE SOUTHWEST
ACROSS THE REGION. CONTEMPLATED AN ADVISORY FOR THIS REGION...BUT
AM COMING UP SHY OF THE 6-12 INCHES NEEDED FOR A WINTER WX
ADVISORY...THOUGH CERTAINLY SUBTLE CHANGES IN THE TRACK AND STRENGTH
OF THE LOW COULD RESULT IN HEAVIER AMOUNTS FOR THIS REGION.
STICKING TRUE TO THE GRIDS FOR NOW AND WILL LET LATER SHIFTS
REASSESS.
AS FOR SEVERE THUNDERSTORM POTENTIAL ACROSS THE PLAINS...APPEARS
TIMING OF THE INITIAL WAVE THIS AFTERNOON WAS TOO QUICK FOR THE LOW
LEVEL MOISTURE RETURN...AND NICE LINE OF THUNDERSTORMS HAS ALREADY
DEVELOPED AND PUSHED EASTWARD INTO KANSAS. HOWEVER AS SURFACE WINDS
HAVE VEERED MORE EASTERLY DUE TO FALLING SFC PRESSURES ACROSS NEW
MEXICO...40S AND LOWER 50 DEW POINTS HAVE PULLED WESTWARD INTO THE
FAR SOUTHEAST PLAINS. ACTIVITY INCREASING ACROSS NORTHERN NEW
MEXICO MAY STILL HAVE A CHANCE TO INTERACT WITH THIS MOISTURE TO
PRODUCE SOME ISOLATED SEVERE THUNDERSTORMS...WITH HAIL AND GUSTY
WINDS THE PRIMARY STORM THREATS. OVERNIGHT...LATEST HRRR HINTS AT
ANOTHER ROUND CLIPPING BY BACA COUNTY DURING THE 8Z TO 09Z
TIMEFRAME...AND EVEN SOME SPOTTY THUNDERSTORMS POSSIBLE AS FAR WEST
AS THE I-25 CORRIDOR. SO THOUGH MAIN THREAT FOR SEVERE
THUNDERSTORMS WILL BE THIS EVENING...CAN`T RULE OUT A LOW GRADE
SEVERE THREAT ACROSS THE FAR SOUTHEAST PLAINS EVEN DURING THE
OVERNIGHT HOURS...THOUGH THUNDERSTORMS WILL TEND TO BE MORE
ELEVATED. TOMORROW AS THE SURFACE LOW LIFTS INTO SOUTHEAST
CO...COULD SEE SOME ISOLATED THUNDERSTORMS EVEN IN THE MORNING...AND
LAPSE RATES WILL BE STEEP GIVEN THE MID LEVEL COOLING ASSOCIATED
WITH THE SURFACE LOW. NAM12 SHOWS UP TO 1000 J/KG OF CAPE ACROSS
NORTHERN PORTIONS OF THE SE PLAINS DURING THE MORNING...SO COULD
HAVE ANOTHER CHANCE FOR SEVERE THUNDERSTORMS ON FRIDAY. BY
AFTERNOON...DRY AIR SPREADS INTO THE SOUTHEAST PLAINS AS SURFACE LOW
LIFTS NORTHWARD. THIS PUTS THE AXIS OF BEST INSTABILITY ALONG THE
NORTHERN FRINGES OF THE SOUTHEAST PLAINS BY AFTERNOON...PRIMARILY
NORTHEAST EL PASO AND KIOWA COUNTIES. THESE AREAS ARE OUTLOOKED FOR
A MARGINAL SEVERE THREAT TOMORROW...AND THIS LOOKS ON TARGET. COULD
SEE THIS MARGINAL THREAT SLIPPING SOUTHWARD A BIT TO ACCOUNT FOR ANY
STRONG MORNING CONVECTION. BUT AS DRY AIR EXPANDS NORTHWARD...SO
DOES THE POTENTIAL FOR CRITICAL FIRE WEATHER PARAMETERS...ESPECIALLY
ACROSS LAS ANIMAS...BACA...BENT...PROWERS... AND OTERO COUNTIES.
THE MITIGATING FACTOR WILL BE THE POTENTIAL FOR RAINFALL TO WET
FUELS TONIGHT OVER THESE SAME ZONES. GIVEN THIS POTENTIAL...HAVE
NOT GONE OUT WITH A FIRE WEATHER WATCH...BUT IF PRECIPITATION
DOESN`T MATERIALIZE ACROSS A WIDESPREAD ENOUGH AREA ACROSS THESE
REGION...THEN LATER SHIFTS MAY NEED TO HOIST A RED FLAG WARNING. -KT
.LONG TERM...(FRIDAY NIGHT THROUGH THURSDAY)
ISSUED AT 356 PM MDT THU APR 16 2015
FRIDAY NIGHT THROUGH SATURDAY...MODELS HAVE SHIFTED A BIT OVER THE
PST 24 HRS...BUT STILL REMAIN FAIRLY CONSISTENT WITH THE PLACEMENT
AND PATH OF THE UPPER LOW. FRIDAY NIGHT THE LOW PRESSURE SYSTEM IS
FORECAST TO BE CENTERED RIGHT OVER COLORADO...THEN OVER THE NEXT 24
HRS IT WILL WOBBLE A BIT BEFORE SLOWLY EXITING THE STATE VIA THE
EASTERN BORDER. THIS PATTERN WOULD IMPLY THAT THE MTS...ESPECIALLY
THE CONTDVD...WILL GET THE BRUNT OF SNOWFALL...MAINLY THROUGH FRIDAY
NIGHT. THEREFORE...ONGOING WINTER HIGHLIGHTS RUNNING THROUGH 12Z
SATURDAY LOOK REASONABLE. SNOW AMOUNTS WILL THEN TAPER OVER OVER THE
DAY SATURDAY AS TEMPS BEGIN TO WARM AND THE SYSTEM WEAKENS. ISOLATED
TO SCATTERED SHOWERS ARE FORECAST FOR THE REMAINDER OF THE LOWER
ELEVATIONS...AND TEMPS DO NOT LOOK PARTICULARLY COLD WITH MIN TEMPS
IN THE 30S TO AROUND 40 F FOR THE PLAINS...AND MAX TEMPS SATURDAY IN
THE MID 50S TO LOWER 60S.
SUNDAY AND MONDAY...THE UPPER SYSTEM WEAKENS AND EXITS TO THE EAST
LATE SATURDAY...WITH BRISK NW FLOW ALOFT THEN SETTLING IN ACROSS THE
STATE. A COUPLE OF UPPER SHORTWAVES ARE EXPECTED TO DROP DOWN ACROSS
THE STATE ON BOTH DAYS...KEEPING THE THREAT OF SHOWER ACTIVITY FOR
THE CWA IN PLACE. LOOK FOR SCATTERED SHOWERS OVER THE HIGHER
TERRAIN...AND ISOLATED SHOWERS FOR THE PLAINS...WITH MAX TEMPS BOTH
DAYS HOVERING IN THE 50S TO NEAR 60 F.
TUESDAY THROUGH THURSDAY...CONFIDENCE IS FAIRLY LOW FOR WHAT HAPPENS
BEYOND MONDAY...THOUGH LONG RANGE MODELS SEEM TO AGREE ON THE
QUESTION MARK. A TEMPORARY RIDGE BUILDS INTO THE DESERT SW STARTING
TUE...HELPING TO LOWERING PCPN CHANCES AS WELL AS BOOSTING MAX TEMPS
FOR THE PLAINS BACK INTO THE 70S. TWO SEPARATE UPPER CLOSED LOW
SYSTEMS APPROACH STARTING WED NIGHT...ONE OVER THE PAC NW AND THE
OTHER OVER S CA...BUT THIS PATTERN WILL MOST LIKELY GO THROUGH
MULTIPLE ADJUSTMENTS BEFORE THEN. MOORE
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z FRIDAY EVENING)
ISSUED AT 356 PM MDT THU APR 16 2015
CURRENTLY...VFR TO MVFR CONDITIONS FOR THE THREE MAIN TAF SITES OF
KCOS...KPUB AND KALS AS WELL AS FOR MUCH OF THE LOWER ELEVATIONS.
FOR ELEVATIONS ABOVE ROUGHLY 7000 FT...IFR CONDITIONS PREVAILED
DUE TO EXTENSIVE LOWER CLOUD COVER AND ONGOING SNOW SHOWERS.
THE UPPER LOW WILL SLOWLY MOVE FROM THE SW QUAD TO THE CENTRAL
PORTIONS OF THE STATE OVER THE NEXT 24 HRS...BRINGING WAVES OF
RAIN/SNOW SHOWERS TO THE LOWER ELEVATIONS AND SNOW...HEAVY AT
TIMES...TO THE MTS. EXPECT MVFR CONDITIONS FOR KPUB AND KALS OVER
THE NEXT 24 HRS. KCOS IS EXPECTED TO DIP INTO IFR CONDITIONS THIS
EVENING...THEN BRIEFLY DROP DOWN INTO LIFR AFTER 11Z TOMORROW
MORN. CONDITIONS ACROSS THE HIGHER TERRAIN AND MT PASSES WILL
REMAIN IFR TO LIFR. MOORE
&&
.PUB WATCHES/WARNINGS/ADVISORIES...
WINTER WEATHER ADVISORY UNTIL 6 AM MDT SATURDAY FOR COZ059-062-
063.
WINTER WEATHER ADVISORY UNTIL 6 PM MDT FRIDAY FOR COZ076>079.
WINTER STORM WARNING UNTIL 6 AM MDT SATURDAY FOR COZ058-060-061-
072-073-080-082.
RED FLAG WARNING UNTIL 7 PM MDT THIS EVENING FOR COZ224.
WINTER WEATHER ADVISORY UNTIL 6 AM MDT SATURDAY FOR COZ074-075.
WINTER WEATHER ADVISORY FROM 6 PM THIS EVENING TO MIDNIGHT MDT
FRIDAY NIGHT FOR COZ066.
WINTER WEATHER ADVISORY UNTIL MIDNIGHT MDT FRIDAY NIGHT FOR
COZ081.
WINTER WEATHER ADVISORY FROM 6 PM THIS EVENING TO 6 PM MDT
FRIDAY FOR COZ084.
&&
$$
SHORT TERM...KT
LONG TERM...MOORE
AVIATION...MOORE
AREA FORECAST DISCUSSION
NWS DENVER/BOULDER CO
308 PM MDT THU APR 16 2015
.SHORT TERM...(THIS EVENING THROUGH FRIDAY)
ISSUED AT 257 PM MDT THU APR 16 2015
WATER VAPOR SATELLITE IMAGERY SHOWING THE UPPER LEVEL LOW
CENTERED OVER THE FOUR CORNERS AT THIS TIME WITH A SHORT WAVE
ROTATING AROUND IT OVER NORTH CENTRAL NEW MEXICO. THIS WAVE WILL
ROTATE NORTH OVER EASTERN COLORADO TONIGHT BRINGING WIDESPREAD
RAIN AND SNOW TO THE AREA.
IN ADDITION TO THE WAVE PASSING ACROSS THE AREA...UPSLOPE WINDS WILL
REMAIN STRONG AT 20 TO 40 KNOTS ALONG THE FRONT RANGE. EXPECT
MODERATE TO HEAVY SNOW THROUGH THE NIGHT WITH SNOWFALL RATES 1 TO 2
INCHES PER HOUR AT TIMES IN THE FOOTHILLS AND MOUNTAINS. LAPSE RATES
ARE ALSO STEEP...SO A FEW THUNDERSTORMS WILL BE POSSIBLE TONIGHT.
WILL MENTION A SLIGHT CHANCE IN THE FORECAST FOR THE FRONT RANGE AND
EASTERN PLAINS TONIGHT AND FRIDAY. MODELS GENERALLY SHOWING 1 TO 2
INCHES OF PRECIPITATION THROUGH FRIDAY MORNING WITH THIS SYSTEM...A
LITTLE MORE OVER LARIMER COUNTY. SO 1 TO 3 FEET LOOKS ON TRACK FOR
SNOWFALL AMOUNTS IN THE FOOTHILLS AND FRONT RANGE MOUNTAINS.
EXPECT A RAIN/SNOW MIX THIS EVENING BETWEEN 5000 TO 6000 FEET WITH
OCCASIONAL HEAVY SNOW UNDER THE STRONGEST SHOWERS. EASTERLY WINDS
AROUND THE LOW WILL CONTINUE TO PUMP MOISTURE INTO THE AREA ALONG
WITH WARMER AIR. THIS IS EXPECTED TO CHANGE SNOW TO RAIN ACROSS THE
DENVER AREA OVERNIGHT. BY FRIDAY MORNING...EXPECT RAIN FOR MOST
PLACES UNDER 6000 FEET. MAY SEE UP TO 6 INCHES OF SLUSHY SNOW PRIOR
TO CHANGING TO RAIN IN THE DENVER AREA OVERNIGHT...POSSIBLY A LITTLE
MORE NEAR THE FOOTHILLS AND PALMER DIVIDE. WILL ISSUE AN ADVISORY
FOR PARK COUNTY AND PALMER DIVIDE WHERE AN ADDITIONAL 4 TO 8 INCHES
WILL BE POSSIBLE.
ON FRIDAY...THE UPPER LEVEL LOW WILL LIFT INTO COLORADO. AT THE
SURFACE...A LOW WILL MOVE EAST ACROSS EASTERN COLORADO. TO THE NORTH
AND EAST OF THE SURFACE LOW...SURFACE BASED CAPES CLIMB TO AROUND
2000 J/KG BASED ON THE 18Z NAM. WITH STRONG SHEAR IN PLACE...THIS
WILL BE ENOUGH INSTABILITY FOR A CHANCE OF SEVERE
THUNDERSTORMS...MAIN THREATS WILL BE LARGE HAIL UP TO GOLF BALL SIZE
AND TORNADOS. RIGHT NOW APPEARS THE BEST CHANCE WILL BE FROM GREELEY
TO LIMON AND EASTWARD...THOUGH THIS WILL DEPEND ON WHERE THE LOW
TRACKS. FOR THE FOOTHILLS AND MOUNTAINS...STILL LOOKS LIKE IT WILL
STAY COLD ENOUGH FOR SNOW THROUGH THE DAY.
.LONG TERM...(FRIDAY NIGHT THROUGH THURSDAY)
ISSUED AT 257 PM MDT THU APR 16 2015
THE FIRST PART OF THE LONG TERM FORECAST HINGES OF THE LOCATION AND
MOVEMENT OF THE 500 MB UPPER LEVEL LOW PRESSURE SYSTEM. THE MODELS
ARE IN PRETTY GOOD AGREEMENT...HOWEVER JUST A SLIGHT DEVIATION IN
THE UPPER LOW TRACK WOULD AFFECT PRECIPITATION AND SNOWFALL AMOUNTS
ACROSS NORTH CENTRAL AND NORTHEASTERN COLORADO. THE ECMWF HAS BEEN
VERY CONSISTENT AND HAS THE 500 MB LOW CENTERED JUST WEST OF
COLORADO SPRINGS AT 00Z SATURDAY. THE GFS AND NAM MODELS HAVE THE
CENTER NEAR CANON CITY WHICH IS APPROXIMATELY 75 SOUTH OF THE
PREVIOUS TWO RUNS. THESE MODELS THEN TRACK THE LOW TO NEAR DENVER BY
12Z SATURDAY MORNING. AS THE LOW MOVES NORTH DENVER SHOULD SEE A
DECREASE IN PRECIPITATION...HOWEVER THE MOUNTAINS AND FOOTHILLS NEAR
THE WYOMING BORDER COULD STILL BE UNDER THE GUN AS WRAP AROUND
PRECIP WRAPS INTO THE REGION FROM THE NORTH. THE 15Z RUC JUST CAME
IN AND SHOWS THE UPPER LOW TAKING A MORE SOUTHERLY TRACK ACROSS
SOUTHERN COLORADO. THIS TRACK COULD PROLONG THE PRECIP EVENT BUT FOR
NOW WILL GO WITH THE CONSENSUS OF THE GFS...ECMWF AND NAM.
PRECIPITATION CHANCES DECREASE SATURDAY NIGHT INTO SUNDAY AS THE
UPPER LOW WEAKENS AND MOVES INTO THE CENTRAL PLAINS STATES AND A
NORTHWEST FLOW ALOFT DEVELOPS OVER THE STATE.
UNSETTLED WEATHER WILL CONTINUE ACROSS NORTH CENTRAL AND
NORTHEASTERN COLORADO THROUGH MONDAY AS RESIDUAL MOISTURE COMBINES
WITH INSTABILITY DUE TO DAYTIME HEATING. A WEAK SURGE IN THE
NORTHWEST FLOW COULD ENHANCE PRECIPITATION CHANCES. WARMER AND
DRIER WEATHER WILL RETURN TO THE REGION ON TUESDAY AS UPPER LEVEL
HIGH PRESSURE BUILDS OVER THE ROCKY MOUNTAIN REGION.
&&
.AVIATION...(FOR THE TAFS THROUGH 00Z FRIDAY LATE AFTERNOON)
ISSUED AT 257 PM MDT THU APR 16 2015
RAIN AND SNOW WILL CONTINUE THROUGH THE EVENING AND EVENTUALLY TURN
TO RAIN BY FRIDAY MORNING. VISIBILITY WILL FALL TO A QUARTER MILE AT
TIMES IN THE HEAVIER SNOW. CEILINGS WILL BE UNDER 1000 FEET AND ONLY
OCCASIONAL BE HIGHER THAN THAT. NORTHERLY WINDS WILL PREVAIL AT
SPEEDS LESS THAN 20 KNOTS. SNOW ACCUMULATION AT KDEN IS EXPECTED TO
STAY BELOW 3 INCHES...WITH UP TO 6 INCHES POSSIBLE AT KAPA AND KBJC.
IN ADDITION TO THE RAIN/SNOW...ISOLATED THUNDERSTORMS ARE EXPECTED
TO FORM...MAINLY THIS EVENING THEN AGAIN FRIDAY AFTERNOON.
&&
.BOU WATCHES/WARNINGS/ADVISORIES...
WINTER WEATHER ADVISORY FROM 6 PM THIS EVENING TO 6 PM MDT
FRIDAY FOR COZ037-041.
WINTER STORM WARNING UNTIL 6 AM MDT SATURDAY FOR COZ033>036.
&&
$$
SHORT TERM...MEIER
LONG TERM...JK
AVIATION...MEIER
AREA FORECAST DISCUSSION
NWS GRAND JUNCTION CO
1137 AM MDT THU APR 16 2015
.UPDATE...
ISSUED AT 1134 AM MDT THU APR 16 2015
RATHER NARROW BAND OF HEAVIER SNOW STILL PERSISTED ACROSS A
PORTION OF WEST-CENTRAL CO LATE THIS MORNING AS THE FIRST IN
SERIES OF DISTURBANCES ROTATED AROUND A FOUR CORNERS LOW AND NORTH
INTO CO. SNOW HAS TAKEN A BREAK AT MONTROSE BUT CONTINUED AT GRAND
JCT AT 11 AM. SOME AREAS IN THE GRAND VALLEY HAVE SEEN LOCALLY UP
TO AN INCH OR TWO ON GRASSY AREAS PER PUBLIC REPORTS...BUT EXPECT
THIS TO MELT THIS AFTERNOON AS THIS BAND MOVES OUT AND TEMPS WARM.
HOWEVER...DID UPDATE TO LOWER THE HIGH TEMPS TODAY ACROSS THE
CENTRAL FORECAST AREA DUE TO THIS MORNING`S CLOUDS AND PRECIP
HAMPERING THE DIURNAL WARM-UP.
16Z RAP SHOWS ANOTHER WAVE ROTATING NORTH TROUGH CENTRAL CO TONIGHT.
EXPECT THIS TO BRING ANOTHER ROUND OF HEAVIER PRECIP FOR AT LEAST
THE CENTRAL MTNS AND NRN MTNS AS EASTERLY FLOW ALSO BRINGS MORE
MOISTURE ACROSS THE DIVIDE. THE 12Z NAM AND GFS SHOW THE MAIN UPPER
LOW OVER SW CO/NW NM FRI MORNING.
UPDATE ISSUED AT 936 AM MDT THU APR 16 2015
GRAND JCT RADAR INDICATED AN AREA OF ENHANCED PRECIPITATION ACROSS
WEST-CENTRAL CO THIS MORNING. MUCH OF THIS PRECIP WAS SNOW PER
PUBLIC REPORTS AND WEBCAM IMAGES. NOT EXPECTING ANY LONG-LASTING
ACCUMULATIONS IN THESE VALLEYS THOUGH PERIODS OF HEAVIER SNOW MAY
TEMPORARILY WHITEN GRASSY SURFACES. HI-RESOLUTION HRRR AND RAP
MODELS SHOW THIS AREA DECREASING...OR AT LEAST SLIDING NORTH AND
NORTHEAST...BY LATE MORNING. EXPECT TO SEE COVERAGE INCREASE ACROSS
ALL OF THE CENTRAL AND NORTHERN PORTIONS OF THE FORECAST AREA THIS
AFTERNOON AS CONVECTIVE INSTABILITY KICKS IN EVEN MORE.
LET THE FREEZE WARNING EXPIRE AT 9 AM THIS MORNING. SOME AREAS WHERE
SNOW IS OCCURRING MAY STILL BE IN THE UPPER 20S FOR A BIT LONGER
THOUGH...LIKE DELTA/MONTROSE/PAONIA AREAS. FREEZE WATCH REMAINS
FOR THE CORTEZ-YELLOWJACKET AREA EARLY FRI MORNING.
UPDATE ISSUED AT 613 AM MDT THU APR 16 2015
SOCIAL MEDIA REPORTS OF HOWLING WINDS IN THE STEAMBOAT SPRINGS
AREA HAVE BEEN RECEIVED EARLY THIS MORNING...PEAK GUSTS ON SENSORS
IN THE AREA SHOWING 25-35 MPH SO FAR THIS MORNING. PATTERN IS
SETTING UP FOR A POTENTIAL DOWNSLOPE WIND EVENT IN THIS REGION
LATER THIS AFTERNOON AND TONIGHT. STRONG H7 FLOW AROUND NORTH
SIDE OF THE LOW EXPECTED TO EXCEED 50 KTS AND WE HAVE SEEN THIS
TYPE OF FLOW IN THE PAST GENERATE STRONG DOWNSLOPE WINDS IN THE
STEAMBOAT AND ZIRKEL WILDERNESS AREAS. TRACK OF THE UPPER LOW WILL
PLAY CRITICAL ROLE AND MODELS STILL A BIT OUT OF PHASE IN EXACT
PATH...SO WILL CONTINUE TO MONITOR AND ADVISE LATER SHIFTS OF THIS
POTENTIAL. IN THE MEANTIME...BOOSTED SPEEDS UP A FEW CATEGORIES
FOR TODAY WITH GUSTS UP TO 50 MPH FOR THE HILLS AND GUST TO UP TO 45
FOR THE VALLEYS.
&&
.SHORT TERM...(TODAY THROUGH FRIDAY)
ISSUED AT 416 AM MDT THU APR 16 2015
SPRING IN THE CENTRAL ROCKIES IS REARING ITS UGLY HEAD AS
TEMPERATURES THIS MORNING HAVE DIPPED BELOW FREEZING IN MANY
LOCATIONS WHICH HAVE ALREADY BEGUN THEIR GROWING SEASONS...WHILE
OTHERS (THE EASTERN UINTAS) HAVE ALREADY SEEN A DECENT AMOUNT OF
ACCUMULATING SNOW. A LARGE CLOSED LOW IS CURRENTLY OVER SOUTHEAST
UTAH AND WILL SLOWLY PROGRESS SOUTH TO THE FOUR CORNERS LATER THIS
MORNING. MODELS ARE IN GOOD AGREEMENT THAT SIGNIFICANT SNOW IS
GOING TO FALL AT ELEVATIONS MAINLY HIGHER THAN 9000 FT STARTING
THIS AFTERNOON ACROSS THE WEST CENTRAL COLORADO MOUNTAINS AND WILL
CONTINUE TO FALL OVER THE EASTERN UINTAS. THOUGH WINDS WILL NOT BE
FAVORABLE FOR CONSTANT SNOWFALL DURING THE ENTIRE TIME PERIOD OF
THE WINTER HAZARDS...WHEN THE DIRECTION IS RIGHT COMBINED WITH
LIFTING DUE TO THE PASSING CLOSED LOW...HEAVY WET SNOW WILL PILE
UP QUICKLY AT THESE HIGHER LOCATIONS. HAVE KEPT A CLOSE EYE ON THE
MOISTURE FIELDS OVER THE LAST FEW DAYS AND HAVE SEEN THE FORECAST
MODELS INCREASE MOISTURE FROM THE SOUTH AND NOW INCREASE MOISTURE
ACROSS WESTERN CO AND EASTERN UT AS IT WRAPS AROUND THE SLOWLY
PROGRESSING CLOSED LOW. THE SLOW MOVEMENT AND DYNAMICS OF THE LOW
SHOULD BE EFFECTIVE IN OVERCOMING THE MOUNTAIN SHADOW EFFECT. SPEC
HUMIDITY VALUES ARE NOW BEING PROGGED TO REACH AND EXCEED 4 G/KG
WHICH IS RATHER SIGNIFICANT WITH SUCH A COLD SYSTEM IN APRIL. SNOW
LEVEL IS DEFINITELY A CHALLENGE AND AM EXPECTING NORTHERN COLORADO
VALLEYS TO SEE MAINLY RAIN AND A RAIN/SNOW MIX WITH LITTLE
ACCUMULATION. AN UPTICK IN ACTIVITY IS EXPECTED THIS AFTERNOON AND
EVENING...BUT ALL FORECAST MODELS REALLY PICK UP COVERAGE IN
ACTIVITY FRIDAY AFTERNOON. CONDITIONS NORTH OF I-70 TODAY WILL BE
BREEZY AND WET MUCH OF TODAY. ELSEWHERE WILL RECEIVE SCATTERED
SHOWERS WITH THE EXCEPTION OF THE CENTRAL MOUNTAINS WHICH WILL SEE
DETERIORATING CONDITIONS TODAY.
ADDED NORTHERN SAN JUANS TO A WINTER STORM WATCH STARTING TONIGHT
AS WE ANTICIPATE FLOW CHANGING TO WEST NORTHWESTERLY. STRONG
NORTHERLY FLOW FRIDAY EVENING WILL ALSO BE FAVORABLE FOR THIS AREA
TO RECEIVE HEAVY SNOW IF THE LOW STAYS ON TRACK. CONFIDENCE IS
MODERATE ON CURRENT SOLUTIONS EVEN A COUPLE DAYS OUT DUE TO THE
LOW TRACKING SO SLOWLY ACROSS THE REGION.
.LONG TERM...(FRIDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 416 AM MDT THU APR 16 2015
MEANDERING LOW WILL CONTINUE TO WREAK HAVOC ON THE FORECAST AS WE
START OFF THIS EXTENDED PERIOD. DEEP NORTHERLY FLOW ON THE BACK
SIDE OF THE...EXPECTED TO BE EXITING LOW PRESSURE SYSTEM...MAY
KEEP LOCALLY HEAVY SNOW FALLING ACROSS THE NORTHWEST SAN JUAN
MOUNTAINS AND OTHER FAVORED NORTH FACING SLOPES IN WESTERN
COLORADO. THIS SYSTEM LOOKS TO LINGER OVER THE AREA UNTIL MIDDAY
SATURDAY...BEFORE A KICKING WAVE DROPS INTO MONTANA LATE SATURDAY
AFTERNOON AND EVENING. THIS SYSTEM SHOULD KICK THE LOW OUT INTO
THE PLAINS WITH SOMEWHAT MOIST NW FLOW HOLDING IN PLACE THROUGH
THE REMAINDER OF THE WEEKEND. SO EXPECT UNSETTLED CONDITIONS TO
CONTINUE OVER THE NORTHERN AND CENTRAL MOUNTAINS WITH ADDITIONAL
LATE SEASON SNOWFALL ANTICIPATED...ESPECIALLY ABOVE THE 9K LEVEL.
SLIGHT INCREASE IN HEIGHTS EXPECTED AS WE MOVE INTO THE NEW WORK
WEEK...WHICH WILL MODIFY TEMPS UP A BIT. HOWEVER...ENOUGH PACIFIC
MOISTURE STREAMING INTO THE REGION TO KEEP ISOLATED TO SCATTERED
POPS ROLLING THROUGHOUT THE PERIOD...GENERALLY FOCUSED ON THE
HIGHER TERRAIN. ANOTHER STRONG CLOSED LOW BEING ADVERTISED BY BOTH
THE GFS AND ECMWF LATE NEXT WEEK PROMISES TO BRING MORE WIDESPREAD
PRECIPITATION TO THE REGION AS WE CLOSE THE WEEK OUT. EXPECT
TEMPS TO BE RUNNING NEAR TO SLIGHTLY BELOW NORMAL THROUGH THIS
PERIOD.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z FRIDAY AFTERNOON)
ISSUED AT 1054 AM MDT THU APR 16 2015
A STRONG LOW PRESSURE SYSTEM NEAR THE FOUR CORNERS AREA THIS
AFTERNOON AND THIS EVENING...WILL MEANDER SLOWLY INTO SOUTH-
CENTRAL COLORADO BY MIDDAY FRIDAY. EXPECT WIDESPREAD SHOWERS
ACROSS THE REGION BY THIS AFTERNOON...WITH LOCALLY HEAVY SNOW
EXPECTED OVER THE MOUNTAINS THROUGH SATURDAY. SNOW WILL SWITCH
OVER TO RAIN IN THE LOWER VALLEYS AT TIMES THIS AFTERNOON. CIGS
AND VSBY WILL DROP IN SHOWERS WITH AREAS OF MVFR AND IFR CONDS.
THESE POOR CONDITIONS WILL BECOME MORE WIDESPREAD LATER TONIGHT.
MOUNTAINS WILL BECOME OBSCURED... ESPECIALLY NEAR SHOWERS. GUSTY
EASTERLY WINDS CAN BE EXPECTED ACROSS WESTERN COLORADO AND EASTERN
UTAH THROUGH FRIDAY MORNING.
&&
.GJT WATCHES/WARNINGS/ADVISORIES...
CO...WINTER WEATHER ADVISORY UNTIL NOON MDT SATURDAY FOR COZ004-009-
013.
WINTER STORM WARNING UNTIL NOON MDT SATURDAY FOR COZ010-012.
WINTER STORM WATCH FROM LATE TONIGHT THROUGH SATURDAY MORNING
FOR COZ018.
FREEZE WATCH FROM LATE TONIGHT THROUGH FRIDAY MORNING FOR COZ021.
UT...WINTER STORM WARNING UNTIL 6 AM MDT SATURDAY FOR UTZ023.
&&
$$
UPDATE...JAD
SHORT TERM...JAM
LONG TERM...JDC
AVIATION...EH
AREA FORECAST DISCUSSION
NWS GRAND JUNCTION CO
1054 AM MDT THU APR 16 2015
.UPDATE...
ISSUED AT 936 AM MDT THU APR 16 2015
GRAND JCT RADAR INDICATED AN AREA OF ENHANCED PRECIPITATION ACROSS
WEST-CENTRAL CO THIS MORNING. MUCH OF THIS PRECIP WAS SNOW PER
PUBLIC REPORTS AND WEBCAM IMAGES. NOT EXPECTING ANY LONG-LASTING
ACCUMULATIONS IN THESE VALLEYS THOUGH PERIODS OF HEAVIER SNOW MAY
TEMPORARILY WHITEN GRASSY SURFACES. HI-RESOLUTION HRRR AND RAP
MODELS SHOW THIS AREA DECREASING...OR AT LEAST SLIDING NORTH AND
NORTHEAST...BY LATE MORNING. EXPECT TO SEE COVERAGE INCREASE ACROSS
ALL OF THE CENTRAL AND NORTHERN PORTIONS OF THE FORECAST AREA THIS
AFTERNOON AS CONVECTIVE INSTABILITY KICKS IN EVEN MORE.
LET THE FREEZE WARNING EXPIRE AT 9 AM THIS MORNING. SOME AREAS WHERE
SNOW IS OCCURRING MAY STILL BE IN THE UPPER 20S FOR A BIT LONGER
THOUGH...LIKE DELTA/MONTROSE/PAONIA AREAS. FREEZE WATCH REMAINS
FOR THE CORTEZ-YELLOWJACKET AREA EARLY FRI MORNING.
UPDATE ISSUED AT 613 AM MDT THU APR 16 2015
SOCIAL MEDIA REPORTS OF HOWLING WINDS IN THE STEAMBOAT SPRINGS
AREA HAVE BEEN RECEIVED EARLY THIS MORNING...PEAK GUSTS ON SENSORS
IN THE AREA SHOWING 25-35 MPH SO FAR THIS MORNING. PATTERN IS
SETTING UP FOR A POTENTIAL DOWNSLOPE WIND EVENT IN THIS REGION
LATER THIS AFTERNOON AND TONIGHT. STRONG H7 FLOW AROUND NORTH
SIDE OF THE LOW EXPECTED TO EXCEED 50 KTS AND WE HAVE SEEN THIS
TYPE OF FLOW IN THE PAST GENERATE STRONG DOWNSLOPE WINDS IN THE
STEAMBOAT AND ZIRKEL WILDERNESS AREAS. TRACK OF THE UPPER LOW WILL
PLAY CRITICAL ROLE AND MODELS STILL A BIT OUT OF PHASE IN EXACT
PATH...SO WILL CONTINUE TO MONITOR AND ADVISE LATER SHIFTS OF THIS
POTENTIAL. IN THE MEANTIME...BOOSTED SPEEDS UP A FEW CATEGORIES
FOR TODAY WITH GUSTS UP TO 50 MPH FOR THE HILLS AND GUST TO UP TO 45
FOR THE VALLEYS.
&&
.SHORT TERM...(TODAY THROUGH FRIDAY)
ISSUED AT 416 AM MDT THU APR 16 2015
SPRING IN THE CENTRAL ROCKIES IS REARING ITS UGLY HEAD AS
TEMPERATURES THIS MORNING HAVE DIPPED BELOW FREEZING IN MANY
LOCATIONS WHICH HAVE ALREADY BEGUN THEIR GROWING SEASONS...WHILE
OTHERS (THE EASTERN UINTAS) HAVE ALREADY SEEN A DECENT AMOUNT OF
ACCUMULATING SNOW. A LARGE CLOSED LOW IS CURRENTLY OVER SOUTHEAST
UTAH AND WILL SLOWLY PROGRESS SOUTH TO THE FOUR CORNERS LATER THIS
MORNING. MODELS ARE IN GOOD AGREEMENT THAT SIGNIFICANT SNOW IS
GOING TO FALL AT ELEVATIONS MAINLY HIGHER THAN 9000 FT STARTING
THIS AFTERNOON ACROSS THE WEST CENTRAL COLORADO MOUNTAINS AND WILL
CONTINUE TO FALL OVER THE EASTERN UINTAS. THOUGH WINDS WILL NOT BE
FAVORABLE FOR CONSTANT SNOWFALL DURING THE ENTIRE TIME PERIOD OF
THE WINTER HAZARDS...WHEN THE DIRECTION IS RIGHT COMBINED WITH
LIFTING DUE TO THE PASSING CLOSED LOW...HEAVY WET SNOW WILL PILE
UP QUICKLY AT THESE HIGHER LOCATIONS. HAVE KEPT A CLOSE EYE ON THE
MOISTURE FIELDS OVER THE LAST FEW DAYS AND HAVE SEEN THE FORECAST
MODELS INCREASE MOISTURE FROM THE SOUTH AND NOW INCREASE MOISTURE
ACROSS WESTERN CO AND EASTERN UT AS IT WRAPS AROUND THE SLOWLY
PROGRESSING CLOSED LOW. THE SLOW MOVEMENT AND DYNAMICS OF THE LOW
SHOULD BE EFFECTIVE IN OVERCOMING THE MOUNTAIN SHADOW EFFECT. SPEC
HUMIDITY VALUES ARE NOW BEING PROGGED TO REACH AND EXCEED 4 G/KG
WHICH IS RATHER SIGNIFICANT WITH SUCH A COLD SYSTEM IN APRIL. SNOW
LEVEL IS DEFINITELY A CHALLENGE AND AM EXPECTING NORTHERN COLORADO
VALLEYS TO SEE MAINLY RAIN AND A RAIN/SNOW MIX WITH LITTLE
ACCUMULATION. AN UPTICK IN ACTIVITY IS EXPECTED THIS AFTERNOON AND
EVENING...BUT ALL FORECAST MODELS REALLY PICK UP COVERAGE IN
ACTIVITY FRIDAY AFTERNOON. CONDITIONS NORTH OF I-70 TODAY WILL BE
BREEZY AND WET MUCH OF TODAY. ELSEWHERE WILL RECEIVE SCATTERED
SHOWERS WITH THE EXCEPTION OF THE CENTRAL MOUNTAINS WHICH WILL SEE
DETERIORATING CONDITIONS TODAY.
ADDED NORTHERN SAN JUANS TO A WINTER STORM WATCH STARTING TONIGHT
AS WE ANTICIPATE FLOW CHANGING TO WEST NORTHWESTERLY. STRONG
NORTHERLY FLOW FRIDAY EVENING WILL ALSO BE FAVORABLE FOR THIS AREA
TO RECEIVE HEAVY SNOW IF THE LOW STAYS ON TRACK. CONFIDENCE IS
MODERATE ON CURRENT SOLUTIONS EVEN A COUPLE DAYS OUT DUE TO THE
LOW TRACKING SO SLOWLY ACROSS THE REGION.
.LONG TERM...(FRIDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 416 AM MDT THU APR 16 2015
MEANDERING LOW WILL CONTINUE TO WREAK HAVOC ON THE FORECAST AS WE
START OFF THIS EXTENDED PERIOD. DEEP NORTHERLY FLOW ON THE BACK
SIDE OF THE...EXPECTED TO BE EXITING LOW PRESSURE SYSTEM...MAY
KEEP LOCALLY HEAVY SNOW FALLING ACROSS THE NORTHWEST SAN JUAN
MOUNTAINS AND OTHER FAVORED NORTH FACING SLOPES IN WESTERN
COLORADO. THIS SYSTEM LOOKS TO LINGER OVER THE AREA UNTIL MIDDAY
SATURDAY...BEFORE A KICKING WAVE DROPS INTO MONTANA LATE SATURDAY
AFTERNOON AND EVENING. THIS SYSTEM SHOULD KICK THE LOW OUT INTO
THE PLAINS WITH SOMEWHAT MOIST NW FLOW HOLDING IN PLACE THROUGH
THE REMAINDER OF THE WEEKEND. SO EXPECT UNSETTLED CONDITIONS TO
CONTINUE OVER THE NORTHERN AND CENTRAL MOUNTAINS WITH ADDITIONAL
LATE SEASON SNOWFALL ANTICIPATED...ESPECIALLY ABOVE THE 9K LEVEL.
SLIGHT INCREASE IN HEIGHTS EXPECTED AS WE MOVE INTO THE NEW WORK
WEEK...WHICH WILL MODIFY TEMPS UP A BIT. HOWEVER...ENOUGH PACIFIC
MOISTURE STREAMING INTO THE REGION TO KEEP ISOLATED TO SCATTERED
POPS ROLLING THROUGHOUT THE PERIOD...GENERALLY FOCUSED ON THE
HIGHER TERRAIN. ANOTHER STRONG CLOSED LOW BEING ADVERTISED BY BOTH
THE GFS AND ECMWF LATE NEXT WEEK PROMISES TO BRING MORE WIDESPREAD
PRECIPITATION TO THE REGION AS WE CLOSE THE WEEK OUT. EXPECT
TEMPS TO BE RUNNING NEAR TO SLIGHTLY BELOW NORMAL THROUGH THIS
PERIOD.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z FRIDAY AFTERNOON)
ISSUED AT 1054 AM MDT THU APR 16 2015
A STRONG LOW PRESSURE SYSTEM NEAR THE FOUR CORNERS AREA THIS
AFTERNOON AND THIS EVENING...WILL MEANDER SLOWLY INTO SOUTH-
CENTRAL COLORADO BY MIDDAY FRIDAY. EXPECT WIDESPREAD SHOWERS
ACROSS THE REGION BY THIS AFTERNOON...WITH LOCALLY HEAVY SNOW
EXPECTED OVER THE MOUNTAINS THROUGH SATURDAY. SNOW WILL SWITCH
OVER TO RAIN IN THE LOWER VALLEYS AT TIMES THIS AFTERNOON. CIGS
AND VSBY WILL DROP IN SHOWERS WITH AREAS OF MVFR AND IFR CONDS.
THESE POOR CONDITIONS WILL BECOME MORE WIDESPREAD LATER TONIGHT.
MOUNTAINS WILL BECOME OBSCURED... ESPECIALLY NEAR SHOWERS. GUSTY
EASTERLY WINDS CAN BE EXPECTED ACROSS WESTERN COLORADO AND EASTERN
UTAH THROUGH FRIDAY MORNING.
&&
.GJT WATCHES/WARNINGS/ADVISORIES...
CO...WINTER WEATHER ADVISORY UNTIL NOON MDT SATURDAY FOR COZ004-009-
013.
WINTER STORM WARNING UNTIL NOON MDT SATURDAY FOR COZ010-012.
WINTER STORM WATCH FROM LATE TONIGHT THROUGH SATURDAY MORNING
FOR COZ018.
FREEZE WATCH FROM LATE TONIGHT THROUGH FRIDAY MORNING FOR COZ021.
UT...WINTER STORM WARNING UNTIL 6 AM MDT SATURDAY FOR UTZ023.
&&
$$
UPDATE...JAD
SHORT TERM...JAM
LONG TERM...JDC
AVIATION...EH
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
259 PM CDT THU APR 16 2015
.UPDATE...
1113 AM CDT
TEMPERATURE AND PRECIPITATION TRENDS APPEAR TO BE ON TRACK LATE
THIS MORNING UNDER SIGNIFICANT CLOUD COVER WITH A FEW AREAS OF
PATCHY DRIZZLE MAINLY SOUTH OF THE LAKE. LIGHT WINDS UNDER THE
CLOUD DECK ARE NOT ASSISTING THE MIXING OUT OF LOW LEVEL
MOISTURE...BUT RAP RH TRENDS AND RECENT SATELLITE LOOPS SUGGEST
THE CLOUDS WILL BE SCATTERING OUT LATER THIS AFTERNOON WHICH
WOULD ALLOW TEMPERATURES TO CLIMB RAPIDLY AS SEEN ACROSS NORTHWEST
ILLINOIS AND EASTERN IOWA. FOR AREAS THAT DO NOT MANAGE TO CLEAR
AS EARLY...HIGHS MAY NEED TO BE TWEAKED DOWNWARD A FEW DEGREES.
LENNING
&&
.SHORT TERM...
304 AM CDT
THROUGH FRIDAY...
COMPACT BUT STRONG VORT IS MOVING NORTHWARD ACROSS ILLINOIS THIS
MORNING AND DRIVING AN AREA OF SHOWERS AND EMBEDDED THUNDERSTORMS
NORTHWARD ACROSS FAR EASTERN ILLINOIS AND WESTERN INDIANA EARLY THIS
MORNING. THIS ACTIVITY WILL AFFECT CHICAGO AREA AND NW INDY INTO THE
EARLY MORNING HOURS BEFORE MOVING OUT OF THE REGION. FAIRLY
EXTENSIVE CLOUD COVER UPSTREAM AND WITH RAIN LIKELY TO FURTHER
SATURATED THE COLUMN AM CONCERNED THAT CLOUD COVER COULD BE FAIRLY
PREVALENT ACROSS ESPECIALLY EASTERN PORTIONS OF THE CWA INTO AT
LEAST THE FIRST PART OF THE AFTERNOON WHICH SHOULD SLOW TEMPERATURE
RISE AND LIKELY KEEP TEMPS FROM GETTING ABOVE GUIDANCE TODAY UNLIKE
THE PAST COUPLE DAYS.
IN THE WAKE OF THIS MORNING`S SHORTWAVE LOOK FOR HEIGHT RISES AS
UPPER RIDGING BUILDS INTO THE REGION IN ADVANCE OF THE BIG WESTERN
CUT-OFF LOW. RISING HEIGHTS AND WARMING LOW/MID LEVEL LOOK TO SET
THE STAGE FOR A COUPLE OF RATHER TOASTY DAYS AWAY FROM THE
LAKEFRONT. PROGGED 925MB TEMPS INTO THE MID TEENS CELSIUS SUPPORT
HIGHS AROUND 80F AND HAVE BUMPED TEMPS IN THE GRIDS UPWARD TOWARD
THE DIRECTION...AND GIVEN THE RECENT COOL BIAS IN GUIDANCE ITS
POSSIBLE THAT THESE FORECAST GRIDS COULD END UP TOO COOL STILL WITH
80F+ ACROSS MOST OF THE CWA FRIDAY AND SATURDAY.
IZZI
&&
.LONG TERM...
304 AM CDT
FRIDAY NIGHT THROUGH WEDNESDAY...
GUIDANCE IS REMAINS IN RELATIVELY GOOD AGREEMENT ON THE EJECTION OF
THE BIG WESTERN CLOSED LOW WITH SHOWERS AND THUNDERSTORMS IN ADVANCE
OF THIS SYSTEM EXPECTED TO ARRIVE PROBABLY SUNDAY AND COULD STICK
AROUND AT TIMES INTO SUNDAY NIGHT. GFS REMAINS IS ON THE FASTER END
OF THE GUIDANCE ENVELOPE...BUT GIVEN THE TENDENCY FOR THESE SYSTEMS
TO BE SLOWER THAN PROGGED HAVE KEPT POPS BELOW GUIDANCE SAT NIGHT
MORE IN LINE WITH THE SLOWER GEM SOLUTION.
THE WESTERN CUT OFF LOW IS PROGGED TO PHASE WITH AMPLIFYING NORTHERN
STREAM LONG TROUGH THAT LOOKS TO STALL OUT OVER THE GREAT LAKES
REGION NEXT WEEK. THIS WILL RESULT IN AN END TO THE ABOVE AVERAGE
TEMPERATURES THAT HAVE DOMINATED MUCH OF THIS MONTH...BUT LOOKS TO
BE A FAIRLY DRY PATTERN THROUGH THURSDAY.
IZZI
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 20Z...
* LIGHT AND VARIABLE WINDS FAVORING EAST AND NORTHEAST THROUGH THE
AFTERNOON.
MDB
//DISCUSSION...UPDATED 18Z...
MVFR LEVEL CLOUDS ARE QUICKLY ERODING LEAVING A VFR DECK OF AROUND
6000 FT. THIS DECK WILL MOVE DRIFT EAST AND PROBABLY ERODE A BIT
THROUGH THE AFTERNOON WITH SOME STRATO CU DEVELOPING ON THE
FRINGES...WHICH WOULD ALSO BE VFR. OTHERWISE LIGHT AND VARIABLE
WINDS WILL BE THE RULE THROUGH THE AFTERNOON AND EVEN THE REST OF
THE NIGHT. EXPECT THAT ORD/MDW WILL FAVOR AN EAST TO NORTHEAST
DIRECTION THANKS TO LAKE INFLUENCES BUT STILL SEE QUITE A BIT OF
VARIABILITY. GYY WOULD LIKELY BE NORTH TO NORTHEAST WITH
VARIABILITY. MANY AREAS WILL PROBABLY EVEN GO CALM AT TIMES. THERE
MAY BE SOME FOG THAT DEVELOPS TONIGHT BUT GIVEN THE DRY CONDITIONS
OF THE PAST FEW DAYS AND ONLY SOME SPOTTY SHOWERS/DRIZZLE THIS
MORNING THE POTENTIAL IS PRETTY LOW.
MDB
//ORD AND MDW CONFIDENCE...UPDATED 20Z...
* HIGH CONFIDENCE IN WIND FORECAST.
MDB
//OUTLOOK FOR ORD/MDW FOR 00Z SATURDAY-12Z THURSDAY...UPDATED 12Z...
FRIDAY NIGHT...VFR. WX NIL. SOUTHEAST WINDS LESS THAN 10 KT.
SATURDAY...VFR...THEN SLIGHT CHANCE SHRA/MVFR AFTER MIDNIGHT. EAST
WINDS 10-15 KT.
SUNDAY...LIKELY SHRA/CHANCE TSRA. MVFR POSSIBLE. EAST WINDS 10-15
KT...BECMG NORTHWEST LESS THAN 10 KT OVERNIGHT.
MONDAY...CHANCE SHRA MONDAY...SLIGHT CHANCE SHRA OVERNIGHT. MVFR
POSSIBLE. WEST TO NORTHWEST WINDS 10-15 KT.
TUESDAY...SLIGHT CHANCE SHRA...OTRW VFR. WEST WINDS 15-20KT
TUESDAY...DIMINISHING TO 5-10 KT OVERNIGHT.
WEDNESDAY...SLIGHT CHANCE SHRA...OTRW VFR. WEST WINDS LESS THAN 10
KT.
KREIN
&&
.MARINE...
304 AM CDT
A RELATIVELY QUIET PERIOD OF WEATHER IS EXPECTED FOR LAKE MICHIGAN
FOR THE NEXT SEVERAL DAYS. HIGH PRESSURE CENTERED OVER SOUTHERN
QUEBEC WILL MOVE OFF THE NEW ENGLAND COAST TODAY...AS LOW PRESSURE
OVER NORTHERN ONTARIO MOVES ACROSS JAMES BAY. MEANWHILE...LOW
PRESSURE OVER THE CENTRAL PLAINS WILL SLOWLY DRIFT SOUTHEAST. WITH
A WEAK PRESSURE GRADIENT OVER THE LAKE...LIGHT WINDS WILL COVER
THE OPEN WATERS WHILE ONSHORE FLOW AND A LAKE BREEZE DEVELOP OVER
THE NEARSHORE WATERS TODAY. A SIMILARLY SETUP IS EXPECTED FOR
FRIDAY...BUT THEN A DEEPENING LOW WILL PASS TO THE NORTH OF LAKE
SUPERIOR FRIDAY EVENING WITH AN ASSOCIATED COLD FRONT PUSHING
SOUTH DOWN LAKE MICHIGAN FRIDAY NIGHT...ALLOWING FOR STRENGTHENING
NORTH TO NORTHEAST WINDS TO DEVELOP OVER THE LAKE FOLLOWING THE
FROPA...BUT DO NOT EXPECT WINDS TO EXCEED 20-25 KT. HIGH PRESSURE
WILL THEN BUILD SOUTHEAST ACROSS THE GREAT LAKES AND ONTARIO
FRIDAY NIGHT INTO SATURDAY.
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...NONE.
&&
$$
VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
WWW.FACEBOOK.COM/NWSCHICAGO
WWW.TWITTER.COM/NWSCHICAGO
WWW.YOUTUBE.COM/NWSCHICAGO
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
1210 PM CDT THU APR 16 2015
.UPDATE...
1113 AM CDT
TEMPERATURE AND PRECIPITATION TRENDS APPEAR TO BE ON TRACK LATE
THIS MORNING UNDER SIGNIFICANT CLOUD COVER WITH A FEW AREAS OF
PATCHY DRIZZLE MAINLY SOUTH OF THE LAKE. LIGHT WINDS UNDER THE
CLOUD DECK ARE NOT ASSISTING THE MIXING OUT OF LOW LEVEL
MOISTURE...BUT RAP RH TRENDS AND RECENT SATELLITE LOOPS SUGGEST
THE CLOUDS WILL BE SCATTERING OUT LATER THIS AFTERNOON WHICH
WOULD ALLOW TEMPERATURES TO CLIMB RAPIDLY AS SEEN ACROSS NORTHWEST
ILLINOIS AND EASTERN IOWA. FOR AREAS THAT DO NOT MANAGE TO CLEAR
AS EARLY...HIGHS MAY NEED TO BE TWEAKED DOWNWARD A FEW DEGREES.
LENNING
&&
.SHORT TERM...
304 AM CDT
THROUGH FRIDAY...
COMPACT BUT STRONG VORT IS MOVING NORTHWARD ACROSS ILLINOIS THIS
MORNING AND DRIVING AN AREA OF SHOWERS AND EMBEDDED THUNDERSTORMS
NORTHWARD ACROSS FAR EASTERN ILLINOIS AND WESTERN INDIANA EARLY THIS
MORNING. THIS ACTIVITY WILL AFFECT CHICAGO AREA AND NW INDY INTO THE
EARLY MORNING HOURS BEFORE MOVING OUT OF THE REGION. FAIRLY
EXTENSIVE CLOUD COVER UPSTREAM AND WITH RAIN LIKELY TO FURTHER
SATURATED THE COLUMN AM CONCERNED THAT CLOUD COVER COULD BE FAIRLY
PREVALENT ACROSS ESPECIALLY EASTERN PORTIONS OF THE CWA INTO AT
LEAST THE FIRST PART OF THE AFTERNOON WHICH SHOULD SLOW TEMPERATURE
RISE AND LIKELY KEEP TEMPS FROM GETTING ABOVE GUIDANCE TODAY UNLIKE
THE PAST COUPLE DAYS.
IN THE WAKE OF THIS MORNING`S SHORTWAVE LOOK FOR HEIGHT RISES AS
UPPER RIDGING BUILDS INTO THE REGION IN ADVANCE OF THE BIG WESTERN
CUT-OFF LOW. RISING HEIGHTS AND WARMING LOW/MID LEVEL LOOK TO SET
THE STAGE FOR A COUPLE OF RATHER TOASTY DAYS AWAY FROM THE
LAKEFRONT. PROGGED 925MB TEMPS INTO THE MID TEENS CELSIUS SUPPORT
HIGHS AROUND 80F AND HAVE BUMPED TEMPS IN THE GRIDS UPWARD TOWARD
THE DIRECTION...AND GIVEN THE RECENT COOL BIAS IN GUIDANCE ITS
POSSIBLE THAT THESE FORECAST GRIDS COULD END UP TOO COOL STILL WITH
80F+ ACROSS MOST OF THE CWA FRIDAY AND SATURDAY.
IZZI
&&
.LONG TERM...
304 AM CDT
FRIDAY NIGHT THROUGH WEDNESDAY...
GUIDANCE IS REMAINS IN RELATIVELY GOOD AGREEMENT ON THE EJECTION OF
THE BIG WESTERN CLOSED LOW WITH SHOWERS AND THUNDERSTORMS IN ADVANCE
OF THIS SYSTEM EXPECTED TO ARRIVE PROBABLY SUNDAY AND COULD STICK
AROUND AT TIMES INTO SUNDAY NIGHT. GFS REMAINS IS ON THE FASTER END
OF THE GUIDANCE ENVELOPE...BUT GIVEN THE TENDENCY FOR THESE SYSTEMS
TO BE SLOWER THAN PROGGED HAVE KEPT POPS BELOW GUIDANCE SAT NIGHT
MORE IN LINE WITH THE SLOWER GEM SOLUTION.
THE WESTERN CUT OFF LOW IS PROGGED TO PHASE WITH AMPLIFYING NORTHERN
STREAM LONG TROUGH THAT LOOKS TO STALL OUT OVER THE GREAT LAKES
REGION NEXT WEEK. THIS WILL RESULT IN AN END TO THE ABOVE AVERAGE
TEMPERATURES THAT HAVE DOMINATED MUCH OF THIS MONTH...BUT LOOKS TO
BE A FAIRLY DRY PATTERN THROUGH THURSDAY.
IZZI
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 18Z...
* LIGHT AND VARIABLE WINDS FAVORING EAST AND NORTHEAST THROUGH THE
AFTERNOON.
MDB
//DISCUSSION...UPDATED 18Z...
MVFR LEVEL CLOUDS ARE QUICKLY ERODING LEAVING A VFR DECK OF AROUND
6000 FT. THIS DECK WILL MOVE DRIFT EAST AND PROBABLY ERODE A BIT
THROUGH THE AFTERNOON WITH SOME STRATO CU DEVELOPING ON THE
FRINGES...WHICH WOULD ALSO BE VFR. OTHERWISE LIGHT AND VARIABLE
WINDS WILL BE THE RULE THROUGH THE AFTERNOON AND EVEN THE REST OF
THE NIGHT. EXPECT THAT ORD/MDW WILL FAVOR AN EAST TO NORTHEAST
DIRECTION THANKS TO LAKE INFLUENCES BUT STILL SEE QUITE A BIT OF
VARIABILITY. GYY WOULD LIKELY BE NORTH TO NORTHEAST WITH
VARIABILITY. MANY AREAS WILL PROBABLY EVEN GO CALM AT TIMES. THERE
MAY BE SOME FOG THAT DEVELOPS TONIGHT BUT GIVEN THE DRY CONDITIONS
OF THE PAST FEW DAYS AND ONLY SOME SPOTTY SHOWERS/DRIZZLE THIS
MORNING THE POTENTIAL IS PRETTY LOW.
MDB
//ORD AND MDW CONFIDENCE...UPDATED 18Z...
* HIGH CONFIDENCE IN WIND FORECAST.
MDB
//OUTLOOK FOR ORD/MDW FOR 00Z SATURDAY-12Z THURSDAY...UPDATED 12Z...
FRIDAY NIGHT...VFR. WX NIL. SOUTHEAST WINDS LESS THAN 10 KT.
SATURDAY...VFR...THEN SLIGHT CHANCE SHRA/MVFR AFTER MIDNIGHT. EAST
WINDS 10-15 KT.
SUNDAY...LIKELY SHRA/CHANCE TSRA. MVFR POSSIBLE. EAST WINDS 10-15
KT...BECMG NORTHWEST LESS THAN 10 KT OVERNIGHT.
MONDAY...CHANCE SHRA MONDAY...SLIGHT CHANCE SHRA OVERNIGHT. MVFR
POSSIBLE. WEST TO NORTHWEST WINDS 10-15 KT.
TUESDAY...SLIGHT CHANCE SHRA...OTRW VFR. WEST WINDS 15-20KT
TUESDAY...DIMINISHING TO 5-10 KT OVERNIGHT.
WEDNESDAY...SLIGHT CHANCE SHRA...OTRW VFR. WEST WINDS LESS THAN 10
KT.
KREIN
&&
.MARINE...
304 AM CDT
A RELATIVELY QUIET PERIOD OF WEATHER IS EXPECTED FOR LAKE MICHIGAN
FOR THE NEXT SEVERAL DAYS. HIGH PRESSURE CENTERED OVER SOUTHERN
QUEBEC WILL MOVE OFF THE NEW ENGLAND COAST TODAY...AS LOW PRESSURE
OVER NORTHERN ONTARIO MOVES ACROSS JAMES BAY. MEANWHILE...LOW
PRESSURE OVER THE CENTRAL PLAINS WILL SLOWLY DRIFT SOUTHEAST. WITH
A WEAK PRESSURE GRADIENT OVER THE LAKE...LIGHT WINDS WILL COVER
THE OPEN WATERS WHILE ONSHORE FLOW AND A LAKE BREEZE DEVELOP OVER
THE NEARSHORE WATERS TODAY. A SIMILARLY SETUP IS EXPECTED FOR
FRIDAY...BUT THEN A DEEPENING LOW WILL PASS TO THE NORTH OF LAKE
SUPERIOR FRIDAY EVENING WITH AN ASSOCIATED COLD FRONT PUSHING
SOUTH DOWN LAKE MICHIGAN FRIDAY NIGHT...ALLOWING FOR STRENGTHENING
NORTH TO NORTHEAST WINDS TO DEVELOP OVER THE LAKE FOLLOWING THE
FROPA...BUT DO NOT EXPECT WINDS TO EXCEED 20-25 KT. HIGH PRESSURE
WILL THEN BUILD SOUTHEAST ACROSS THE GREAT LAKES AND ONTARIO
FRIDAY NIGHT INTO SATURDAY.
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...NONE.
&&
$$
VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
WWW.FACEBOOK.COM/NWSCHICAGO
WWW.TWITTER.COM/NWSCHICAGO
WWW.YOUTUBE.COM/NWSCHICAGO
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
1126 AM CDT THU APR 16 2015
.UPDATE...
1113 AM CDT
TEMPERATURE AND PRECIPITATION TRENDS APPEAR TO BE ON TRACK LATE
THIS MORNING UNDER SIGNIFICANT CLOUD COVER WITH A FEW AREAS OF
PATCHY DRIZZLE MAINLY SOUTH OF THE LAKE. LIGHT WINDS UNDER THE
CLOUD DECK ARE NOT ASSISTING THE MIXING OUT OF LOW LEVEL
MOISTURE...BUT RAP RH TRENDS AND RECENT SATELLITE LOOPS SUGGEST
THE CLOUDS WILL BE SCATTERING OUT LATER THIS AFTERNOON WHICH
WOULD ALLOW TEMPERATURES TO CLIMB RAPIDLY AS SEEN ACROSS NORTHWEST
ILLINOIS AND EASTERN IOWA. FOR AREAS THAT DO NOT MANAGE TO CLEAR
AS EARLY...HIGHS MAY NEED TO BE TWEAKED DOWNWARD A FEW DEGREES.
LENNING
&&
.SHORT TERM...
304 AM CDT
THROUGH FRIDAY...
COMPACT BUT STRONG VORT IS MOVING NORTHWARD ACROSS ILLINOIS THIS
MORNING AND DRIVING AN AREA OF SHOWERS AND EMBEDDED THUNDERSTORMS
NORTHWARD ACROSS FAR EASTERN ILLINOIS AND WESTERN INDIANA EARLY THIS
MORNING. THIS ACTIVITY WILL AFFECT CHICAGO AREA AND NW INDY INTO THE
EARLY MORNING HOURS BEFORE MOVING OUT OF THE REGION. FAIRLY
EXTENSIVE CLOUD COVER UPSTREAM AND WITH RAIN LIKELY TO FURTHER
SATURATED THE COLUMN AM CONCERNED THAT CLOUD COVER COULD BE FAIRLY
PREVALENT ACROSS ESPECIALLY EASTERN PORTIONS OF THE CWA INTO AT
LEAST THE FIRST PART OF THE AFTERNOON WHICH SHOULD SLOW TEMPERATURE
RISE AND LIKELY KEEP TEMPS FROM GETTING ABOVE GUIDANCE TODAY UNLIKE
THE PAST COUPLE DAYS.
IN THE WAKE OF THIS MORNING`S SHORTWAVE LOOK FOR HEIGHT RISES AS
UPPER RIDGING BUILDS INTO THE REGION IN ADVANCE OF THE BIG WESTERN
CUT-OFF LOW. RISING HEIGHTS AND WARMING LOW/MID LEVEL LOOK TO SET
THE STAGE FOR A COUPLE OF RATHER TOASTY DAYS AWAY FROM THE
LAKEFRONT. PROGGED 925MB TEMPS INTO THE MID TEENS CELSIUS SUPPORT
HIGHS AROUND 80F AND HAVE BUMPED TEMPS IN THE GRIDS UPWARD TOWARD
THE DIRECTION...AND GIVEN THE RECENT COOL BIAS IN GUIDANCE ITS
POSSIBLE THAT THESE FORECAST GRIDS COULD END UP TOO COOL STILL WITH
80F+ ACROSS MOST OF THE CWA FRIDAY AND SATURDAY.
IZZI
&&
.LONG TERM...
304 AM CDT
FRIDAY NIGHT THROUGH WEDNESDAY...
GUIDANCE IS REMAINS IN RELATIVELY GOOD AGREEMENT ON THE EJECTION OF
THE BIG WESTERN CLOSED LOW WITH SHOWERS AND THUNDERSTORMS IN ADVANCE
OF THIS SYSTEM EXPECTED TO ARRIVE PROBABLY SUNDAY AND COULD STICK
AROUND AT TIMES INTO SUNDAY NIGHT. GFS REMAINS IS ON THE FASTER END
OF THE GUIDANCE ENVELOPE...BUT GIVEN THE TENDENCY FOR THESE SYSTEMS
TO BE SLOWER THAN PROGGED HAVE KEPT POPS BELOW GUIDANCE SAT NIGHT
MORE IN LINE WITH THE SLOWER GEM SOLUTION.
THE WESTERN CUT OFF LOW IS PROGGED TO PHASE WITH AMPLIFYING NORTHERN
STREAM LONG TROUGH THAT LOOKS TO STALL OUT OVER THE GREAT LAKES
REGION NEXT WEEK. THIS WILL RESULT IN AN END TO THE ABOVE AVERAGE
TEMPERATURES THAT HAVE DOMINATED MUCH OF THIS MONTH...BUT LOOKS TO
BE A FAIRLY DRY PATTERN THROUGH THURSDAY.
IZZI
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 16Z...
* LIGHT NORTHEAST WINDS WHICH WILL BE VARIABLE AT TIMES.
* MVFR CIGS IMPROVING TO VFR MID/LATE AFTERNOON.
MDB
//DISCUSSION...UPDATED 16Z...
IFR HAS IMPROVED TO MVFR EXCEPT FOR AREAS SOUTH OF THE TERMINALS.
AM STILL THINKING THAT ORD/MDW MAY SEE LOWERING OF CIGS TOWARDS
015 IN THE NEXT 1-2 HRS BEFORE LIFTING AND EVENTUALLY SCATTERING
OCCURS. WINDS HAVE DROPPED OFF AND THE DIRECTION HAS BECOME QUITE
VARIABLE ACROSS THE TERMINALS BUT EXPECT THE LAKE INFLUENCE TO
PROVIDE A SOMEWHAT STEADIER EAST TO NORTHEAST DIRECTION AT ORD/MDW
AND NORTH TO NORTHEAST DIRECTION AT GYY LATER THIS AFTERNOON. MAY
ALSO SEE A SLIGHT BUMP IN SPEEDS AS THIS OCCURS.
MDB
FROM 12Z...
A WEAK MID LEVEL CIRCULATION MOVING NWD ALONG THE IL/IN BORDER.
SCT SHOWERS ASSOCIATED WITH THE MID LEVEL CIRCULATION HAVE MOVED
INTO FAR NERN IL AND NWRN IN...MAINLY IMPACTING GYY/ORD/MDW. THE
POTENTIAL FOR ANY PCPN REACHING THE GROUND AT DPA IS DIMINISHING
AS THE MID LEVEL CIRCULATION SHOULD TAKE A TURN TO THE NORTHEAST
LATER THIS MORNING. WITH THE ARRIVAL OF SHOWERS OVER THE EASTERN
TERMINALS...FORECAST SOUNDINGS INDICATE A PERIOD OF MVFR...AND
POSSIBLY IFR CIGS THROUGH LATE THIS MORNING. LIGHT WINDS BY THAT
TIME SUGGEST MVFR CIGS MAY BE A LITTLE SLOW TO LIFT/SCATTER...AND
POSSIBLE MAY NOT IMPROVE TO VFR UNTIL THIS AFTERNOON.
THERE IS ALSO A CHANCE FOR SOME THUNDERSTORMS INVOF THE
CIRCULATION CENTER...BUT IT IS UNLIKELY THAT ANY THUNDER WILL
IMPACT THE TERMINALS...AND SHOULD REMAIN TO THE SOUTHEAST.
WITH A WEAK GRADIENT IN PLACE...WINDS ARE EXPECTED TO BECOME
NORTHEAST NEAR LAKE MICHIGAN...WHILE THE MORE INLAND SITES DPA
AND RFD ARE LIKELY SEE LIGHT NORTH-NORTHWEST WINDS THIS AFTERNOON.
KREIN
//ORD AND MDW CONFIDENCE...UPDATED 16Z...
* HIGH CONFIDENCE IN IN MVFR CIGS PERSISTING THROUGH EARLY
AFTERNOON WITH MEDIUM CONFIDENCE IN TIMING OF SCATTERING.
* HIGH CONFIDENCE IN LIGHT WIND SPEEDS AND VARIABLE WIND
DIRECTION. MEDIUM-HIGH CONFIDENCE IT WILL FAVOR A NORTHEAST TO
EAST DIRECTION.
MDB
//OUTLOOK FOR ORD/MDW FOR 00Z SATURDAY-12Z THURSDAY...UPDATED 12Z...
FRIDAY NIGHT...VFR. WX NIL. SOUTHEAST WINDS LESS THAN 10 KT.
SATURDAY...VFR...THEN SLIGHT CHANCE SHRA/MVFR AFTER MIDNIGHT. EAST
WINDS 10-15 KT.
SUNDAY...LIKELY SHRA/CHANCE TSRA. MVFR POSSIBLE. EAST WINDS 10-15
KT...BECMG NORTHWEST LESS THAN 10 KT OVERNIGHT.
MONDAY...CHANCE SHRA MONDAY...SLIGHT CHANCE SHRA OVERNIGHT. MVFR
POSSIBLE. WEST TO NORTHWEST WINDS 10-15 KT.
TUESDAY...SLIGHT CHANCE SHRA...OTRW VFR. WEST WINDS 15-20KT
TUESDAY...DIMINISHING TO 5-10 KT OVERNIGHT.
WEDNESDAY...SLIGHT CHANCE SHRA...OTRW VFR. WEST WINDS LESS THAN 10
KT.
KREIN
&&
.MARINE...
304 AM CDT
A RELATIVELY QUIET PERIOD OF WEATHER IS EXPECTED FOR LAKE MICHIGAN
FOR THE NEXT SEVERAL DAYS. HIGH PRESSURE CENTERED OVER SOUTHERN
QUEBEC WILL MOVE OFF THE NEW ENGLAND COAST TODAY...AS LOW PRESSURE
OVER NORTHERN ONTARIO MOVES ACROSS JAMES BAY. MEANWHILE...LOW
PRESSURE OVER THE CENTRAL PLAINS WILL SLOWLY DRIFT SOUTHEAST. WITH
A WEAK PRESSURE GRADIENT OVER THE LAKE...LIGHT WINDS WILL COVER
THE OPEN WATERS WHILE ONSHORE FLOW AND A LAKE BREEZE DEVELOP OVER
THE NEARSHORE WATERS TODAY. A SIMILARLY SETUP IS EXPECTED FOR
FRIDAY...BUT THEN A DEEPENING LOW WILL PASS TO THE NORTH OF LAKE
SUPERIOR FRIDAY EVENING WITH AN ASSOCIATED COLD FRONT PUSHING
SOUTH DOWN LAKE MICHIGAN FRIDAY NIGHT...ALLOWING FOR STRENGTHENING
NORTH TO NORTHEAST WINDS TO DEVELOP OVER THE LAKE FOLLOWING THE
FROPA...BUT DO NOT EXPECT WINDS TO EXCEED 20-25 KT. HIGH PRESSURE
WILL THEN BUILD SOUTHEAST ACROSS THE GREAT LAKES AND ONTARIO
FRIDAY NIGHT INTO SATURDAY.
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...NONE.
&&
$$
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AREA FORECAST DISCUSSION
NWS DODGE CITY KS
121 PM CDT THU APR 16 2015
...UPDATED SHORT TERM SECTION...
.SHORT TERM...(THIS EVENING THROUGH FRIDAY)
ISSUED AT 120 PM CDT THU APR 16 2015
IN THE SHORT TERM, A FEW (2-3) ROUNDS OF CONVECTION ARE ANTICIPATED
THROUGH HE NEXT 24 TO 36 HOURS OR SO AS A LARGE UPPER LOW MOVES
TOWARD THE REGION WITH FORCING FOR ASCENT, AND PERSISTENT MID LEVEL
MOISTURE ADVECTION TO MAINTAIN INSTABILITY FOR A PROLONGED PERIOD.
THE FIRST ROUNDS ARE EXPECTED ALREADY EARLY THIS AFTERNOON AS THE
NESTED 4 KM NAM AND HRRR MODELS HAVE GENERALLY AGREED ON CONVECTIVE
INITIATION BETWEEN AROUND 2 AND 4 PM, AND RAPIDLY DEVELOPING INTO A
MULTICELLULAR LINE AFTER AN HOUR OR SO OF SLOWER GROWING DISCREET
CELLS. THE INITIAL ROTATING STORMS GENERALLY WEST OF HIGHWAY 83
SHOULD BE CAPABLE OF PRODUCING HAIL LARGER THAN GOLFBALLS AND
DAMAGING WIND BEFORE THE STORMS BECOME MORE CLUSTERED OR LINEAR,
PRESENTING A SLIGHTLY SMALLER HAIL THREAT AND STILL DAMAGING WIND
THREAT THROUGH THE HIGHWAY 283 AND 183 CORRIDORS INTO THE EARLY
EVENING HOURS. THESE MODEL SOLUTIONS COULD BE INTERFERED WITH BY THE
EXTENSIVE STRATUS ACROSS THE AREA REDUCING THE SEVERE THREAT.
ANOTHER ROUND OF THUNDERSTORMS WILL PROBABLY OCCUR LATE TONIGHT INTO
THE OVERNIGHT AND POSSIBLY STILL ONGOING EARLY FRIDAY MORNING, WITH
A CONTINUED HAIL IF NOT AN ISOLATED WIND THREAT AS WELL, ALTHOUGH
SOME BL STABILITY SHOULD HINDER THE WIND THREAT. THE DYNAMICS OF THE
UPPER LOW WILL DRIVE A DRY SLOT THROUGH THE REGION OF FRIDAY, BUT
NOT BEFORE LATE MORNING/EARLY AFTERNOON DESTABILIZATION CONTRIBUTES
TO YET ANOTHER SEVERE EPISODE WITH AS GOOD OR BETTER CAPE AND SHEAR
COMBINATIONS.
TEMPERATURES WERE RAISED FOR FRIDAY MORNING, FOLLOWING THE NAM AND
GFS, AS OVERNIGHT CONVECTION SHOULD LIMIT THE RADIATIONAL COOLING.
ADDITIONALLY THE POPS WERE RAISED LOWERED FRIDAY MORNING AND
INCREASED ALONG THE MOISTURE TRANSPORT AXIS INTO FRIDAY AFTERNOON
WITH A MODEL CONSENSUS.
.LONG TERM...(FRIDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 1152 AM CDT THU APR 16 2015
FRIDAY NIGHT INTO SATURDAY WE WILL STILL BE DEALING WITH THE SLOW-
MOVING UPPER LOW, BUT BY THIS TIME THE LOW WILL BE SEVERELY OCCLUDED
WITH THE DRY INTRUSION WORKING IN FAST FROM THE SOUTHWEST. IN FACT,
FRIDAY NIGHT LOOKS RATHER DRY NOW WITH THE SYNOPTIC DRY INTRUSION
ACROSS MUCH OF KANSAS. WE HAVE REDUCED POPS AS A RESULT FRIDAY
NIGHT. AS WE HEAD INTO SATURDAY, ANY DAYTIME HEATING WILL PROMOTE
SHOWER AND ISOLATED THUNDERSTORM DEVELOPMENT AS THE CORE OF THE MID
LEVEL CYCLONE WALLOWS SLOWLY EASTWARD INTO FAR WESTERN KANSAS. WE
WILL MAINTAIN THE 20-40 POPS ACROSS MAINLY THE NORTHERN AND EASTERN
ZONES WITH A DRY FORECAST ACROSS FAR SOUTHWEST KANSAS.
WHAT IS LEFT OF THE LOW WILL FINALLY PULL AWAY SATURDAY NIGHT INTO
EARLY SUNDAY WITH FAIRLY STRONG NORTH WINDS TO FOLLOW DURING THE DAY
SUNDAY. WE COULD STILL SEE SOME WRAP-AROUND LIGHT PRECIPITATION IN
THE WEAKENING MID LEVEL DEFORMATION AXIS, HENCE THE 20 TOP 30 POPS
FOR MUCH OF THE AREA. LOOKING BEYOND THE WEEKEND, WE WILL ENTER A
NORTHWEST FLOW PATTERN ON THE SOUTHWEST SIDE OF A LARGE-SCALE UPPER
TROUGH ACROSS THE GREAT LAKES REGION. THE ATMOSPHERE WILL BE FAIRLY
COOL EARLY NEXT WEEK AS A RESULT WITH LARGE SCALE HIGH PRESSURE AT
THE SURFACE.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z FRIDAY AFTERNOON)
ISSUED AT 112 PM CDT THU APR 16 2015
SEVERE STORMS ARE EXPECTED LATER THIS AFTERNOON AND EARLY EVENING,
AND WILL BE ACCOUNTED FOR IN LOCAL TERMINALS. THE CONVECTION IS
MODELED BY THE CONVECTIVE ALLOWING MODELS TO GO FAIRLY
MULTICELLULAR, OR A BROKEN LINE WITH BOTH HAIL AND WIND THREAT EARLY
INTO THE EVENING, BUT BEGINNING AS ISOLATED TO SCATTERED AS EARLY AS
20-22 UTC.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 54 70 49 69 / 70 60 60 50
GCK 52 68 44 69 / 60 60 60 40
EHA 51 67 42 66 / 60 30 30 30
LBL 54 70 46 69 / 60 50 40 30
HYS 53 69 49 71 / 80 70 60 50
P28 56 71 54 72 / 70 60 60 50
&&
.DDC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...RUSSELL
LONG TERM...UMSCHEID
AVIATION...RUSSELL
AREA FORECAST DISCUSSION
NWS JACKSON KY
616 PM EDT THU APR 16 2015
.UPDATE...
ISSUED AT 615 PM EDT THU APR 16 2015
UPDATED POPS FROM FRIDAY INTO SATURDAY. LATEST MODEL RUNS SUGGEST
THE TIME FRAME FROM LATE FRIDAY THROUGH SATURDAY WILL LIKELY BE
DRY.
&&
.SHORT TERM...(THIS EVENING THROUGH FRIDAY NIGHT)
ISSUED AT 306 PM EDT THU APR 16 2015
WITH THE LATEST RUN OF THE HRRR MODEL BEING A BIT OFF WITH ITS
HANDLING OF TODAYS CONVECTION...THE NAM12 WAS MODEL OF CHOICE FOR
THE SHORT TERM PORTION OF THE FORECAST. SHOWERS AND STORMS THAT
HAVE BEEN MOVING ACROSS EASTERN KENTUCKY THROUGHOUT THE DAY ARE
CURRENTLY AFFECTING THE NORTHEASTERN PORTION OF THE THE AREA. THIS
ACTIVITY IS EXPECTED TO MOVE ON OUT OF THE AREA IN THE NEXT FEW
HOURS. CURRENT RADAR INDICATES THAT ISOLATED TO SCATTERED SHOWERS
AND STORMS WILL CONTINUE TO MOVE INTO THE AREA FROM THE SOUTHWEST
DURING THE REMAINDER OF THE AFTERNOON AND EVENING HOURS. ONLY
ISOLATED ACTIVITY...IF THAT...WILL BE LEFT OVER FOR THE OVERNIGHT
HOURS. SHOWERS AND STORMS WILL BE POSSIBLE DURING THE DAY ON
FRIDAY...AS A WEAK FRONTAL BOUNDARY MOVES IN FROM THE WEST. WEAK
DISTURBANCES AHEAD OF THIS FRONT MAY ALSO KICK OFF SHOWERS AND
STORMS...BUT WITH A LACK OF INSTABILITY AND STRONG LIFT...IT
APPEARS THAT THE COVERAGE OF PRECIPITATION WILL BE SPARSE. BASED
ON THE LATEST MODEL DATA...THERE SHOULD BE LULL IN THE ACTION FROM
LATE FRIDAY AFTERNOON THROUGH EARLY SATURDAY MORNING...AS A WEAK
RIDGE OF HIGH PRESSURE BRIEFLY SETTLES OVER THE AREA.
TEMPERATURES DURING THE PERIOD WILL BE WELL ABOVE NORMAL FOR THIS
TIME OF YEAR...WITH HIGHS ON FRIDAY MAXING OUT IN THE 70S...AND
OVERNIGHT LOWS TONIGHT AND FRIDAY NIGHT BOTTOMING OUT IN THE LOW
TO MID 50S AREA WIDE.
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 340 PM EDT THU APR 16 2015
MAIN CONCERN DURING THE EXTENDED PERIOD IS FOCUSED ON A CUT OFF LOW
CURRENTLY OVER THE FOUR CORNERS REGION. THIS LOW IS PROGGED TO
PUSH SLOWLY EWD EARLY SATURDAY BEFORE ITS ENERGY GETS INGESTED AND
HELPS DEEPEN A NORTHERN STREAM TROUGH. THIS TROUGH WILL MOVE ALONG
THE US/CANADIAN BORDER UNTIL THE CLOSED LOW ENERGY PHASES WITH IT
AND MOVES EAST. IN ADDITION TO THE UPPER LEVEL TROUGH...A SFC LOW
IS FORECASTED TO DEVELOP SATURDAY NIGHT OVER THE PLAINS AND AHEAD
OF IT...A STRONG SURGE OF GULF MOISTURE RETURNS TO THE OH AND TN
VALLEYS. PW VALUES UP TO 1.4 INCHES ARE EXPECTED WITH THIS NEW
SURGE OF MOISTURE....WHICH ARE WELL ABOVE AVERAGE. THERE WILL BE
SOME MODERATE INSTABILITY AS WELL. THIS SYSTEM SHOULD PUSH OUT OF
KY BY MONDAY NIGHT. ON TUESDAY...A LOW THAT IS NOW CUT OFF IN THE
NORTHERN STREAM WILL UNDULATE OVER THE GREAT LAKES REGION THROUGH
THURSDAY WITH PIECES OF ENERGY WRAPPING AROUND IT. HOWEVER...THIS
SHOULDN/T CAUSE ANY ISSUES FOR KENTUCKY AS THE ENERGY APPEARS TO
STAY FURTHER NORTH UNTIL THURSDAY WHEN THE LOW STARTS SAGGING
SOUTHEASTWARD.
AT THE SFC...SATURDAY WILL BE MAINLY DRY AND WARM UNTIL LATE
AFTERNOON WHEN CHANCES FOR PRECIP BEGIN INCREASING. THE BULK OF
THE RAINFALL WILL FALL SUNDAY INTO MONDAY WHERE AT LEAST AN INCH
OF LIQUID IS LIKELY ACROSS EASTERN KENTUCKY. THERE IS ALSO A
CHANCE FOR THUNDERSTORMS DURING THIS TIME GIVEN THE MOIST AIR MASS
IN PLACE AND PLENTY OF SFC/UPPER LEVEL DYNAMICS. AS THIS SYSTEM
EXITS THE AREA MONDAY NIGHT...THINGS WILL DRY OUT AND EASTERN
KENTUCKY WILL GET A REPRIEVE FROM PRECIPITATION TUESDAY AND
WEDNESDAY. TEMPERATURES DURING THIS TIME WILL BE A BIT BELOW
NORMAL IF NOT RIGHT AT SEASONABLE LEVELS. RAIN CHANCES RETURN ON
THURSDAY AS THE LOW SAGS SOUTHEASTWARD.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z FRIDAY AFTERNOON)
ISSUED AT 145 PM EDT THU APR 16 2015
SCATTERED SHOWERS AND ISOLATED THUNDERSTORMS WILL CONTINUE TO MOVE
ACROSS EASTERN KENTUCKY OVER THE NEXT SEVERAL HOURS. THE OVERALL
TREND OVER THE PAST COUPLE OF HOURS HAS BEEN FOR THE ACTIVITY TO
WEAKEN AND DECREASE IN COVERAGE. THAT BEING SAID...IT LOOKS THERE
WILL BE A MUCH SMALLER CHANCE OF SHOWERS AND STORMS DIRECTLY
AFFECTING ANY OF THE TAF SITES THAN BEFORE. WHERE RAIN DOES
OCCUR...PARTICULARLY WITH THUNDERSTORMS...A TAF SITE MAY
EXPERIENCE BRIEF PERIODS OF MVFR CONDITIONS DURING THE MORE
INTENSE RAIN SHOWERS. THE SHOWERS AND STORMS SHOULD BE MOSTLY OUT
OF THE ARE BY AROUND 2Z THIS EVENING. THERE WILL BE A CHANCE OF
LINGERING SHOWERS AND STORMS OVERNIGHT...AS AN AREA OF DISTURBED
WEATHER PASSES BY THE AREA. ANOTHER BATCH OF ISOLATED TO SCATTERED
SHOWERS AND THUNDERSTORMS IS ON TAP FOR TOMORROW...AS YET ANOTHER
DISTURBANCE MOVES ACROSS THE OHIO AND TENNESSEE VALLEY REGIONS.
THERE SHOULD BE A GOOD LULL IN THE RAIN BETWEEN ROUGHLY 2 AND
12Z...WITH A SLIGHT UPTICK IN THE ACTIVITY AT 12 OR 13Z.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...HAL
SHORT TERM...AR
LONG TERM...JVM
AVIATION...AR
AREA FORECAST DISCUSSION
NWS JACKSON KY
340 PM EDT THU APR 16 2015
.SHORT TERM...(THIS EVENING THROUGH FRIDAY NIGHT)
ISSUED AT 306 PM EDT THU APR 16 2015
WITH THE LATEST RUN OF THE HRRR MODEL BEING A BIT OFF WITH ITS
HANDLING OF TODAYS CONVECTION...THE NAM12 WAS MODEL OF CHOICE FOR
THE SHORT TERM PORTION OF THE FORECAST. SHOWERS AND STORMS THAT
HAVE BEEN MOVING ACROSS EASTERN KENTUCKY THROUGHOUT THE DAY ARE
CURRENTLY AFFECTING THE NORTHEASTERN PORTION OF THE THE AREA. THIS
ACTIVITY IS EXPECTED TO MOVE ON OUT OF THE AREA IN THE NEXT FEW
HOURS. CURRENT RADAR INDICATES THAT ISOLATED TO SCATTERED SHOWERS
AND STORMS WILL CONTINUE TO MOVE INTO THE AREA FROM THE SOUTHWEST
DURING THE REMAINDER OF THE AFTERNOON AND EVENING HOURS. ONLY
ISOLATED ACTIVITY...IF THAT...WILL BE LEFT OVER FOR THE OVERNIGHT
HOURS. SHOWERS AND STORMS WILL BE POSSIBLE DURING THE DAY ON
FRIDAY...AS A WEAK FRONTAL BOUNDARY MOVES IN FROM THE WEST. WEAK
DISTURBANCES AHEAD OF THIS FRONT MAY ALSO KICK OFF SHOWERS AND
STORMS...BUT WITH A LACK OF INSTABILITY AND STRONG LIFT...IT
APPEARS THAT THE COVERAGE OF PRECIPITATION WILL BE SPARSE. BASED
ON THE LATEST MODEL DATA...THERE SHOULD BE LULL IN THE ACTION FROM
LATE FRIDAY AFTERNOON THROUGH EARLY SATURDAY MORNING...AS A WEAK
RIDGE OF HIGH PRESSURE BRIEFLY SETTLES OVER THE AREA.
TEMPERATURES DURING THE PERIOD WILL BE WELL ABOVE NORMAL FOR THIS
TIME OF YEAR...WITH HIGHS ON FRIDAY MAXING OUT IN THE 70S...AND
OVERNIGHT LOWS TONIGHT AND FRIDAY NIGHT BOTTOMING OUT IN THE LOW
TO MID 50S AREA WIDE.
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 340 PM EDT THU APR 16 2015
MAIN CONCERN DURING THE EXTENDED PERIOD IS FOCUSED ON A CUT OFF LOW
CURRENTLY OVER THE FOUR CORNERS REGION. THIS LOW IS PROGGED TO
PUSH SLOWLY EWD EARLY SATURDAY BEFORE ITS ENERGY GETS INGESTED AND
HELPS DEEPEN A NORTHERN STREAM TROUGH. THIS TROUGH WILL MOVE ALONG
THE US/CANADIAN BORDER UNTIL THE CLOSED LOW ENERGY PHASES WITH IT
AND MOVES EAST. IN ADDITION TO THE UPPER LEVEL TROUGH...A SFC LOW
IS FORECASTED TO DEVELOP SATURDAY NIGHT OVER THE PLAINS AND AHEAD
OF IT...A STRONG SURGE OF GULF MOISTURE RETURNS TO THE OH AND TN
VALLEYS. PW VALUES UP TO 1.4 INCHES ARE EXPECTED WITH THIS NEW
SURGE OF MOISTURE....WHICH ARE WELL ABOVE AVERAGE. THERE WILL BE
SOME MODERATE INSTABILITY AS WELL. THIS SYSTEM SHOULD PUSH OUT OF
KY BY MONDAY NIGHT. ON TUESDAY...A LOW THAT IS NOW CUT OFF IN THE
NORTHERN STREAM WILL UNDULATE OVER THE GREAT LAKES REGION THROUGH
THURSDAY WITH PIECES OF ENERGY WRAPPING AROUND IT. HOWEVER...THIS
SHOULDN/T CAUSE ANY ISSUES FOR KENTUCKY AS THE ENERGY APPEARS TO
STAY FURTHER NORTH UNTIL THURSDAY WHEN THE LOW STARTS SAGGING
SOUTHEASTWARD.
AT THE SFC...SATURDAY WILL BE MAINLY DRY AND WARM UNTIL LATE
AFTERNOON WHEN CHANCES FOR PRECIP BEGIN INCREASING. THE BULK OF
THE RAINFALL WILL FALL SUNDAY INTO MONDAY WHERE AT LEAST AN INCH
OF LIQUID IS LIKELY ACROSS EASTERN KENTUCKY. THERE IS ALSO A
CHANCE FOR THUNDERSTORMS DURING THIS TIME GIVEN THE MOIST AIR MASS
IN PLACE AND PLENTY OF SFC/UPPER LEVEL DYNAMICS. AS THIS SYSTEM
EXITS THE AREA MONDAY NIGHT...THINGS WILL DRY OUT AND EASTERN
KENTUCKY WILL GET A REPRIEVE FROM PRECIPITATION TUESDAY AND
WEDNESDAY. TEMPERATURES DURING THIS TIME WILL BE A BIT BELOW
NORMAL IF NOT RIGHT AT SEASONABLE LEVELS. RAIN CHANCES RETURN ON
THURSDAY AS THE LOW SAGS SOUTHEASTWARD.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z FRIDAY AFTERNOON)
ISSUED AT 145 PM EDT THU APR 16 2015
SCATTERED SHOWERS AND ISOLATED THUNDERSTORMS WILL CONTINUE TO MOVE
ACROSS EASTERN KENTUCKY OVER THE NEXT SEVERAL HOURS. THE OVERALL
TREND OVER THE PAST COUPLE OF HOURS HAS BEEN FOR THE ACTIVITY TO
WEAKEN AND DECREASE IN COVERAGE. THAT BEING SAID...IT LOOKS THERE
WILL BE A MUCH SMALLER CHANCE OF SHOWERS AND STORMS DIRECTLY
AFFECTING ANY OF THE TAF SITES THAN BEFORE. WHERE RAIN DOES
OCCUR...PARTICULARLY WITH THUNDERSTORMS...A TAF SITE MAY
EXPERIENCE BRIEF PERIODS OF MVFR CONDITIONS DURING THE MORE
INTENSE RAIN SHOWERS. THE SHOWERS AND STORMS SHOULD BE MOSTLY OUT
OF THE ARE BY AROUND 2Z THIS EVENING. THERE WILL BE A CHANCE OF
LINGERING SHOWERS AND STORMS OVERNIGHT...AS AN AREA OF DISTURBED
WEATHER PASSES BY THE AREA. ANOTHER BATCH OF ISOLATED TO SCATTERED
SHOWERS AND THUNDERSTORMS IS ON TAP FOR TOMORROW...AS YET ANOTHER
DISTURBANCE MOVES ACROSS THE OHIO AND TENNESSEE VALLEY REGIONS.
THERE SHOULD BE A GOOD LULL IN THE RAIN BETWEEN ROUGHLY 2 AND
12Z...WITH A SLIGHT UPTICK IN THE ACTIVITY AT 12 OR 13Z.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...AR
LONG TERM...JVM
AVIATION...AR
AREA FORECAST DISCUSSION
NWS JACKSON KY
306 PM EDT THU APR 16 2015
.SHORT TERM...(THIS EVENING THROUGH FRIDAY NIGHT)
ISSUED AT 306 PM EDT THU APR 16 2015
WITH THE LATEST RUN OF THE HRRR MODEL BEING A BIT OFF WITH ITS
HANDLING OF TODAYS CONVECTION...THE NAM12 WAS MODEL OF CHOICE FOR
THE SHORT TERM PORTION OF THE FORECAST. SHOWERS AND STORMS THAT
HAVE BEEN MOVING ACROSS EASTERN KENTUCKY THROUGHOUT THE DAY ARE
CURRENTLY AFFECTING THE NORTHEASTERN PORTION OF THE THE AREA. THIS
ACTIVITY IS EXPECTED TO MOVE ON OUT OF THE AREA IN THE NEXT FEW
HOURS. CURRENT RADAR INDICATES THAT ISOLATED TO SCATTERED SHOWERS
AND STORMS WILL CONTINUE TO MOVE INTO THE AREA FROM THE SOUTHWEST
DURING THE REMAINDER OF THE AFTERNOON AND EVENING HOURS. ONLY
ISOLATED ACTIVITY...IF THAT...WILL BE LEFT OVER FOR THE OVERNIGHT
HOURS. SHOWERS AND STORMS WILL BE POSSIBLE DURING THE DAY ON
FRIDAY...AS A WEAK FRONTAL BOUNDARY MOVES IN FROM THE WEST. WEAK
DISTURBANCES AHEAD OF THIS FRONT MAY ALSO KICK OFF SHOWERS AND
STORMS...BUT WITH A LACK OF INSTABILITY AND STRONG LIFT...IT
APPEARS THAT THE COVERAGE OF PRECIPITATION WILL BE SPARSE. BASED
ON THE LATEST MODEL DATA...THERE SHOULD BE LULL IN THE ACTION FROM
LATE FRIDAY AFTERNOON THROUGH EARLY SATURDAY MORNING...AS A WEAK
RIDGE OF HIGH PRESSURE BRIEFLY SETTLES OVER THE AREA.
TEMPERATURES DURING THE PERIOD WILL BE WELL ABOVE NORMAL FOR THIS
TIME OF YEAR...WITH HIGHS ON FRIDAY MAXING OUT IN THE 70S...AND
OVERNIGHT LOWS TONIGHT AND FRIDAY NIGHT BOTTOMING OUT IN THE LOW
TO MID 50S AREA WIDE.
.LONG TERM...(FRIDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 355 AM EDT THU APR 16 2015
THE UPPER LEVEL PATTERN REMAINS IN A SPLIT FLOW TO START THE
EXTENDED WITH MAIN CONCERNS CENTERED AROUND A CLOSED LOW WHICH IS
IN THE PROCESS OF CREEPING EAST FROM THE FOUR CORNERS REGION ON
FRIDAY NIGHT. MEANWHILE...ALONG THE NORTHERN JET STREAM...A STRONG
SHORTWAVE IS CURRENTLY ENTERING THE PACIFIC NORTHWEST. AS THE
MENTIONED CLOSED LOW OPENS AND EJECTS TO THE EAST...THESE TWO
FEATURES BEGIN TO PHASE...DEEPENING THE LONGWAVE TROUGH OVER THE
CENTRAL PLAINS AS THIS FEATURE MOVES EAST. CLOSER TO EAST KENTUCKY
DURING THE FRIDAY NIGHT THROUGH SATURDAY TIME FRAME...WEAK
DISTURBANCES ALONG THE SOUTHERN STREAM MOVING INTO THE AREA WILL
KEEP A SLIGHT CHANCE OF PRECIP FRIDAY NIGHT OVER THE AREA. BY
SATURDAY NIGHT...AS THE MENTIONED DEEPENING TROUGH DEVELOPS...A
STRONG SURFACE LOW PRESSURE DEVELOPS OVER THE PLAINS AND A STRONG
SURGE OF MOISTURE MOVES NORTHEAST INTO THE TN AND OH VALLEYS
SATURDAY NIGHT AND SUNDAY BEHIND A DEVELOPED WARM FRONT. PWATS
WITH THIS LOOK TO BE NEAR 1.40 INCHES IN MOST EAST KENTUCKY
LOCATIONS WITH SOME MODEST INSTABILITY THROUGH SUNDAY.
CONCERNING THIS...THE GFS AND EURO HAVE HAD GOOD AGREEMENT WITH
THIS FEATURE AND CONSISTENCY AS WELL. IN FACT...MOS DATA HAS BEEN
ADVERTISING CAT POPS ACROSS EAST KENTUCKY. COLLABORATING WITH
NEIGHBORS AND WHAT THE MODELS HAVE SHOWN...HAVE GONE ABOVE WHAT
THE SUPER BLEND HAS DISPLAYED FOR EAST KENTUCKY. DESPITE THE
DOWNSLOPE FOR THE BEGINNING OF THIS EVENT LATE SATURDAY
NIGHT...THE SURGE IN MOISTURE WITH THIS WILL QUICKLY OVERTAKE THIS
ADIABATIC PROCESS. BESIDE THE MOISTURE AVAILABLE AND POSSIBLE
FLOOD SCENARIO...THE AMOUNT OF SHEAR THE MODEL SOUNDINGS ARE
ADVERTISING IS CONCERNING. THE ONLY INHIBITING FACTOR HERE IS THE
TIMING OF THE PRECIP AND LACK OF STRONG INSTABILITY.
NEVERTHELESS...WILL GO WITH CAT POPS LATE SATURDAY NIGHT THROUGH
SUNDAY AFTERNOON AND LIKELY POPS THROUGH MONDAY AS ADDITIONAL
MOISTURE MOVES INTO THE AREA. THIS TIME FRAME WILL CONTINUE TO BE
HIGHLIGHTED IN THE HWO FOR POSSIBLE FLOODING AND MAY NEED TO
HIGHLIGHT A SEVERE POTENTIAL...THOUGH THIS ELEMENT IS STILL VAGUE
DUE TO THE TIMING...LACK OF DEEP INSTABILITY...AND TIMING WITH THE
BETTER UPPER LEVEL DYNAMICS ARRIVING LATE IN THE PERIOD.
CONTINUED PRECIP WILL LAST INTO MONDAY AND MONDAY NIGHT AS THE
SURFACE COLD FRONT BEGINS TO PUSH THROUGH. LOOKING AT MODEL
SOUNDINGS MONDAY INTO MONDAY NIGHT...ANOTHER PERIOD OF UNSETTLED
WEATHER LOOKS POSSIBLE. HIGH PRESSURE AND RARE QUIET WEATHER WILL
ARRIVE INTO THE AREA BEHIND THE FRONT FOR THE TUESDAY AFTERNOON
THROUGH WEDNESDAY PERIOD.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z FRIDAY AFTERNOON)
ISSUED AT 145 PM EDT THU APR 16 2015
SCATTERED SHOWERS AND ISOLATED THUNDERSTORMS WILL CONTINUE TO MOVE
ACROSS EASTERN KENTUCKY OVER THE NEXT SEVERAL HOURS. THE OVERALL
TREND OVER THE PAST COUPLE OF HOURS HAS BEEN FOR THE ACTIVITY TO
WEAKEN AND DECREASE IN COVERAGE. THAT BEING SAID...IT LOOKS THERE
WILL BE A MUCH SMALLER CHANCE OF SHOWERS AND STORMS DIRECTLY
AFFECTING ANY OF THE TAF SITES THAN BEFORE. WHERE RAIN DOES
OCCUR...PARTICULARLY WITH THUNDERSTORMS...A TAF SITE MAY
EXPERIENCE BREIF PERIODS OF MVFR CONDITIONS DURING THE MORE
INTENSE RAIN SHOWERS. THE SHOWERS AND STORMS SHOULD BE MOSTLY OUT
OF THE ARE BY AROUND 2Z THIS EVENING. THERE WILL BE A CHANCE OF
LINGERING SHOWERS AND STORMS OVERNIGHT...AS AN AREA OF DISTURBED
WEATHER PASSES BY THE AREA. ANOTHER BATCH OF ISOLATED TO SCATTERED
SHOWERS AND THUNDERSTORMS IS ON TAP FOR TOMORROW...AS YET ANOTHER
DISTURBANCE MOVES ACROSS THE OHIO AND TENNESSEE VALLEY REGIONS.
THERE SHOULD BE A GOOD LULL IN THE RAIN BETWEEN ROUGHLY 2 AND
12Z...WITH A SLIGHT UPTICK IN THE ACTIVITY AT 12 OR 13Z.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...AR
LONG TERM...SHALLENBERGER
AVIATION...AR
AREA FORECAST DISCUSSION
NWS PITTSBURGH PA
217 PM EDT THU APR 16 2015
.SYNOPSIS...
A WEAK UPPER LEVEL DISTURBANCE AND TRAILING COLD FRONT WILL BRING
SHOWERS THIS AFTERNOON INTO FRIDAY MORNING. HIGH PRESSURE WILL
BRING A DRY START TO THE WEEKEND.
&&
.NEAR TERM /THROUGH TONIGHT/...
AREA OF SHOWERS HAS SPREAD ACROSS MUCH OF THE REGION AND WILL
CONTINUE TO MOVE AND DEVELOP NORTHEAST INTO THE EVENING. UPPER
LEVEL TROUGH MOVING INTO THE OHIO VALLEY THIS AFTERNOON WILL KEEP
SHOWER CHANCES IN THE LIKELY CATEGORY UNTIL THIS EVENING WHEN
UPPER TROUGH BEGINS TO SHEAR OUT AND A WEAK BOUNDARY APPROACHES
FROM THE GREAT LAKES. SHOWERS WILL DIMINISH FROM WEST TO EAST
OVERNIGHT AS DEEP MOISTURE IS TAKEN EAST OF THE RIDGES.
TEMPERATURES WILL NOT MOVE MUCH FROM CURRENT READINGS WHERE RAIN
HAS FALLEN. MIN TEMPS TONIGHT INTO THE 40S BUT STILL A BIT ABOVE
AVERAGE.
&&
.SHORT TERM /FRIDAY THROUGH SUNDAY/...
UPPER LEVEL SUPPORT WILL QUICKLY EXIT THE AREA...SO EXPECT THE
SHOWERS TO RAP UP IN THE EAST FRIDAY MORNING. NO REAL DISCERNIBLE
COLD ADVECTION IS EXPECTED...SO TEMPERATURES WILL BE ABLE TO
REBOUND BACK TO...IF NOT WARMER THAN SEASONAL AVERAGES FRIDAY
AFTERNOON.
BROAD SURFACE HIGH AND UPPER LEVEL RIDGE WILL BUILD INTO THE OHIO
VALLEY SATURDAY.
&&
.LONG TERM /SUNDAY NIGHT THROUGH WEDNESDAY/...
MODELS STILL SHOWING A LARGE AND SLOW MOVING SYSTEM THAT WILL
BRING AN EXTENDED PERIOD OF SHOWERS BEGINNING SUNDAY AND
CONTINUING INTO EARLY TUESDAY. DRY AND SEASONABLE WEATHER WILL
RETURN BEHIND THIS SYSTEM.
&&
.AVIATION /18Z THURSDAY THROUGH TUESDAY/...
SHOWERS WILL CONTINUE TO BLOSSOM WITH HELP FROM A PASSING
SHORTWAVE THROUGH THIS AFTERNOON AND EVENING. A GRADUAL
DETERIORATION TO MVFR AND IFR CIGS IS EXPECTED OVERNIGHT AT MOST
PORTS AS THE WEAK FRONTAL BOUNDARY CROSSES. TRIED TO FOLLOW THE
SREF PROBABILITIES AND BUFKIT MOISTURE PROFILES WITH TIMING OF
RESTRICTIONS...AS THE NAM AND LAMP SEEM TO BE A BUT MORE
PESSIMISTIC AT THIS TIME. WHILE VERY BRIEF IFR VISIBILITY MAY BE
EXPECTED IN THE MORE INTENSE SHOWERS...OPTED TO NOT CARRY THIS AT
ANY PARTICULAR SITE AND WILL COVER WITH TEMPOS AS NEEDED.
A ESE TO WSW WIND SHIFT IS ANTICIPATED OVERNIGHT. GRADUAL
IMPROVEMENT BACK TO MVFR WILL OCCUR TOMORROW.
.OUTLOOK.../FRIDAY THROUGH TUESDAY/...
THE NEXT CHANCE FOR GENERAL RESTRICTIONS IS EXPECTED WITH THE
APPROACH OF LOW PRESSURE ON SUNDAY.
&&
.PBZ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
OH...NONE.
PA...NONE.
WV...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS PITTSBURGH PA
124 PM EDT THU APR 16 2015
.SYNOPSIS...
A WEAK UPPER LEVEL DISTURBANCE AND TRAILING COLD FRONT WILL BRING
SHOWERS THIS AFTERNOON INTO FRIDAY MORNING. HIGH PRESSURE WILL
BRING A DRY START TO THE WEEKEND.
&&
.NEAR TERM /THROUGH TONIGHT/...
AREA OF SHOWERS HAS SPREAD ACROSS MUCH OF THE REGION AND WILL
CONTINUE TO MOVE AND DEVELOP NORTHEAST INTO THE EVENING. UPPER
LEVEL TROUGH MOVING INTO THE OHIO VALLEY THIS AFTERNOON WILL KEEP
SHOWER CHANCES IN THE LIKLEY CATAGORY UNTIL THIS EVENING WHEN
UPPER TROUGH BEGINS TO SHEAR OUT AND A WEAK BOUNDARY APPROACHES
FROM THE GREAT ALKES. SHOWERS WILL DIMINISH FROM WEST TO EAST
OVERNIGHT AS DEEP MOISTURE IS TAKEN EAST OF THE RIDGES.
TEMPERATURES WILL NOT MOVE MUCH FROM CURRENT READINGS WHERE RAIN
HAS FALLEN. MIN TEMPS TONIGHT INTO THE 40S BUT STILL A BIT ABOVE
AVERAGE.
&&
.SHORT TERM /FRIDAY THROUGH SATURDAY/...
UPPER LEVEL SUPPORT WILL QUICKLY EXIT THE AREA...SO EXPECT THE
SHOWERS TO RAP UP IN THE EAST FRIDAY MORNING. NO REAL DISCERNIBLE
COLD ADVECTION IS EXPECTED...SO TEMPERATURES WILL BE ABLE TO
REBOUND BACK TO...IF NOT WARMER THAN SEASONAL AVERAGES FRIDAY
AFTERNOON.
BROAD SURFACE HIGH AND UPPER LEVEL RIDGE WILL BUILD INTO THE OHIO
VALLEY SATURDAY.
&&
.LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/...
MODELS STILL SHOWING A LARGE AND SLOW MOVING SYSTEM THAT WILL
BRING AN EXTENDED PERIOD OF SHOWERS BEGINNING SUNDAY AND
CONTINUING INTO EARLY TUESDAY. DRY AND SEASONABLE WEATHER WILL
RETURN BEHIND THIS SYSTEM.
&&
.AVIATION /17Z THURSDAY THROUGH MONDAY/...
LOCAL MVFR CONDITIONS IN SCATTERED SHOWERS THIS AFTERNOON.
INCREASING ESE TURNING SOUTH WINDS SHOULD PRECLUDE VISIBLITY
RESTRICTIONS...HOWEVER CIGS WILL TREND AT LEAST CLOSE TO IFR BY
TONIGHT AS LOW LEVELS BECOME SATURATED.
.OUTLOOK.../FRIDAY THROUGH MONDAY/... THE NEXT CHANCE FOR GENERAL
RESTRICTIONS IS EXPECTED WITH THE APPROACH OF LOW PRESSURE ON
SUNDAY.
&&
.PBZ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
OH...NONE.
PA...NONE.
WV...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
128 PM EDT THU APR 16 2015
.UPDATE...
ISSUED AT 657 AM EDT THU APR 16 2015
DECIDED TO PUT SPRINKLES INTO FORECAST OVER EASTERN CWA /ISQ-ERY/
MID MORNING INTO EARLY AFTN AS BAND OF SHOWERS OVER LOWER MICHIGAN
CONTINUES TO LIFT NORTHWARD. EVEN THOUGH SHRA WILL BE RUNNING INTO
THE DRY AIRMASS OVER AREA AS SEEN ON 00Z APX AND DTX RAOBS...THINK
ENOUGH FOCUS FM SHORTWAVE AND MOISTURE TRANSPORT AT H85-H7 IS GOING
TO END UP STRONG/PERSISTENT ENOUGH TO OUTWEIGH THE LOW-LEVEL DRY
AIR. VARIOUS HIGH RES MODELS AND THE 06Z/07Z HRRR REFLECTIVITY
OUTPUT POINT TO AT LEAST A BRIEF PERIOD OF LGT RAIN/SPRINKLES.
BEEFED UP SKY COVER SOME MORE AS WELL. OTHER THAN TWEAKS FOR VERY
SHORT TERM TEMP/DWPNT TRENDS...NO OTHER CHANGES WERE NEEDED TO
FORECAST.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 435 AM EDT THU APR 16 2015
SHORTWAVE RIDGING PERSISTS TODAY BTWN NORTHERN STREAM SHORTWAVE THAT
CROSSES MANITOBA/NORTHERN ONTARIO AND CUTOFF LOW OVER FOUR CORNERS
OF SW CONUS. WEAK AREAS OF VORTICITY LIFTING INTO THE RIDGE BRINGING
A PUSH OF MID-LEVEL MOISTURE ADVECTION AROUND H7. DECENT AREA OF
SHRA IS LIFTING NORTHWARD OVER WESTERN LOWER MICHIGAN ON NORTH EDGE
OF MOISTURE TRANSPORT AT H85-H7 AND THIS COULD BRING VIRGA OR A FEW
SPRINKLES TO EASTERN CWA...POSSIBLY AS FAR WEST AS KESC PER HRRR
MODEL LATE MORNING INTO EARLY AFTN. ELSEWHERE WILL CERTAINLY BE MORE
CLOUDS THAN LAST COUPLE DAYS AS CIRRUS AND MORE PRONOUNCED AREA OF
AC/AS OVER MN SLIDES IN FOR THE AFTN. EVEN SO THOUGH...WARM START
SHOULD STILL ALLOW MAX TEMPS TO REACH WELL INTO THE 60S. RH VALUES A
BIT HIGHER THAN BONE DRY CONDITIONS SEEN TUE/WED WHERE RH BOTTOMED
OUT AROUND 10 PCT OVER INTERIOR WEST. FOR TODAY IN THOSE AREAS...
EXPECT MAINLY 18-25 PCT RANGE AT THE LOW-END. WINDS LESS THAN 10 MPH
MOST AREAS WITH LOCAL LAKE BREEZES CNTRL. OVERALL APPEARS TO NOT BE
AS MUCH OF ISSUE WITH FIRE WEATHER TODAY COMPARED TO TUE OR WED.
NORTHERN STREAM SHORTWAVE CROSSES NORTHERN ONTARIO TONIGHT WITH
TAIL OF ENHANCED CLOUD GRAZING CWA...ALONG WITH THE PASSAGE OF SFC
TROUGH...MORE OF A WIND SHIFT FM SW TO NW LATE TONIGHT. SINCE 1000-
700MB LAPSE RATES ARE HIGH...OVER 7C/KM BY LATE AFTN...AND FORCING
IS MOVING THROUGH WITH SUFFICIENT MOISTURE ALOFT...THINK THERE IS A
CHANCE OF SPRINKLES/VIRGA THIS EVENING AS THE FORCING MOVES
THROUGH...PERHAPS SIMILAR TO WHAT OCCURRED MON AFTN/EVENING. THAT
SAID...WINDS IN MIXED LAYER THIS EVENING DO INCREASE BY 03Z WITH 25-
30 KTS AT TOP PARTS OF THE MIXED LAYER. SO...FEASIBLE THAT GUSTY
WINDS COULD OCCUR IN THE VCNTY OF ANY WELL DEVELOPED CU OR
VIRGA/SPRINKLES. ALL FORCING IS OUT OF HERE BY MIDNIGHT AND SCT-BKN
CLOUDS SHOULD EXIT OVERNIGHT. SKIES WILL BE MAINLY CLEAR BY DAYBREAK
ON FRIDAY. LOWS TONIGHT SHOULD REMAIN ABOVE FREEZING ALL AREAS GIVEN
THE WINDS AND CLOUDS MOST OF THE NIGHT AND LACK OF COLD AIR BEHIND
THE TROUGH.
.LONG TERM...(THURSDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 436 PM EDT WED APR 15 2015
AFTER A QUIET AND GENERALLY WARM REST OF THIS WEEK...SIGNIFICANT
AMPLIFICATION OF THE FLOW IS EXPECTED THIS WEEKEND AND EARLY NEXT
WEEK AS A SHARP RIDGE BUILDS THRU WRN CANADA. THIS WILL FORCE A DEEP
TROF TO DEVELOP DOWNSTREAM WITH AXIS ROUGHLY OVER THE MISSISSIPPI
VALLEY BY MON. TYPICAL FOR THIS TIME OF YEAR...CLOSED LOWS
FREQUENTLY DEVELOP...AND THIS TROF WILL QUICKLY EVOLVE IN THAT
DIRECTION AS MAJORITY OF GUIDANCE INCLUDING GFS/GEM ENSEMBLES SHOW
EVOLUTION INTO A LARGE/COLD MID-LEVEL LOW OVER THE VICINITY OF THE
UPPER GREAT LAKES. MAY BE DIFFICULT TO DISLODGE THE LOW NEXT WEEK
ONCE IT DEVELOPS. SO...AFTER A WARM/DRY REST OF THIS WEEK...NEXT
WEEK WILL BE COLD AND GENERALLY UNSETTLED WITH PERIODIC CHANCES OF
SNOW AND RAIN SHOWERS. FROM A PCPN PERSPECTIVE...THE BIGGEST
CHALLENGE IS HOW THE SHARP PATTERN AMPLIFICATION INTERACTS WITH WHAT
IS CURRENTLY AN IMPRESSIVE LOOKING TROF CLOSING OFF OVER UT/CO.
MEDIUM RANGE GUIDANCE TODAY IS IN MUCH BETTER AGREEMENT IN SHOWING
THE AMPLIFICATION OF THE FLOW PICKING UP THE MID-LEVEL LOW AND
FORCING THE OPENED UP SYSTEM/REMNANT ENERGY NE INTO THE GREAT LAKES
REGION. RANGE OF POSSIBILITIES STILL INCLUDE A SIGNIFICANT RAIN
EVENT TO A RAIN CHANGING TO ACCUMULATING SNOW EVENT TO MINIMAL PCPN
IF THE SRN ENERGY DOES NOT LIFT FAR ENOUGH N AND W WITHIN THE
AMPLIFYING PATTERN. OPERATIONAL MEDIUM RANGE MODELS WEAKEN THE
ENERGY DRAMATICALLY AS IT LIFTS NE (WILL BE INTERESTING TO SEE IF
THAT ACTUALLY HAPPENS)...SO THE LOWEST PROBABILITY OUTCOME RIGHT NOW
IS ONE THAT BRINGS A SIGNIFICANT PCPN PRODUCING SYSTEM WITH A
PROMINENT DEFORMATION PCPN SHIELD INTO THE UPPER LAKES EARLY NEXT
WEEK. THAT SAID...THERE HAVE BEEN AND THERE STILL ARE SOME GFS/GEM
ENSEMBLES THAT DO SHOW SUCH A SCENARIO...SO IT CAN`T BE RULED OUT.
BEGINNING THU NIGHT...TAIL END OF SHORTWAVE TRACKING FROM HUDSON BAY
INTO QUEBEC WILL PASS ACROSS THE AREA THU NIGHT. FORCING FROM THE
RIGHT ENTRANCE OF AN UPPER JET STREAK AND MAIN DEEP LAYER QVECTOR
CONVERGENCE...WEAK AT THAT...PASS N OF THE AREA...SUPPORTING BEST
CHC OF -SHRA N OF HERE. ACROSS UPPER MI...VERY WEAK FORCING/WEAK
FRONTAL BOUNDARY AND WEAK MOISTURE TRANSPORT ALL SUGGEST PROSPECT OF
ANY PCPN IS VERY LIMITED AS SHORTWAVE PASSES. THUS...WILL RETAIN DRY
FCST FOR THU NIGHT.
IN THE MAIN FLOW TO THE N...ANOTHER SHORTWAVE IS FCST TO TRACK FROM
THE CANADIAN ROCKIES THU AFTN TO NRN ONTARIO FRI. MODELS HAVE
TRENDED TO MUCH BETTER AGREEMENT ON THIS WAVE WITH GEM/GFS/NAM
MOVING TO THE ECMWF SCENARIO WHICH HAS BEEN FARTHER N THAN THOSE
MODELS FOR SEVERAL RUNS. WITH THE TRACK OF THE SHORTWAVE JUST N OF
LAKE SUPERIOR...BEST FORCING AND POTENTIAL FOR PCPN WILL PASS BY TO
THE N. REMOVED SCHC POPS FROM INHERITED FCST IN FAVOR OF DRY
WEATHER. EXPECT HIGH TEMPS FRI IN THE 60S AWAY FROM LAKE MODERATION.
A FEW SPOTS MAY REACH 70F. INTERIOR RH SHOULD FALL TO 25-30PCT...
AND WINDS MAY BE A LITTLE GUSTY TO 15-20MPH AT TIMES...KEEPING FIRE
WX A CONCERN.
IN THE WAKE OF THE SHORTWAVE...HIGH PRES BUILDS INTO THE AREA FOR
SAT. WITH THE HIGH ENDING UP OVER LAKE SUPERIOR IN THE AFTN...IT
WILL BE A MUCH COOLER DAY NEAR LAKE SUPERIOR...ESPECIALLY FROM THE
KEWEENAW EASTWARD. RIGHT ALONG THE SHORE...TEMPS SHOULDN`T GET OUT
OF THE 30S. IN THE INTERIOR W HALF...TEMPS SHOULD RISE TO AROUND 60F
UNDER SUNNY SKIES.
SUN/MON...WILL CONTINUE TO UTILIZE A CONSENSUS APPROACH OF CURRENT
AND RECENT MEDIUM RANGE GUIDANCE FOR THE EVOLUTION OF THE SRN
ROCKIES ENERGY INTO THE GREAT LAKES AHEAD OF THE TROF AMPLIFICATION
OCCURRING INTO THE PLAINS/MISSISSIPPI VALLEY. IT APPEARS THERE MAY
END UP BEING TWO SURGES OF PCPN OR SFC LOW PRES WAVES...ONE
ASSOCIATED WITH LEAD ENERGY SWINGING UP FROM MEXICO AND A SECOND
ASSOCIATED WITH THE MAIN REMNANT OF THE ROCKIES MID LEVEL LOW.
LATEST GUIDANCE SUGGESTS RAIN WILL BEGIN SPREADING INTO UPPER MI SUN
AND THEN CONTINUE INTO MON. AIR MASS SHOULD COOL ENOUGH TO ALLOW
SOME SNOW TO BEGIN MIXING WITH THE RAIN OVER THE W ON MON. PTYPE
WILL THEN BECOME ALL SNOW ACROSS THE FCST AREA MON NIGHT FOR
WHATEVER PCPN LINGERS.
TUE/WED...LARGE/COLD MID-LEVEL LOW WILL HAVE DEVELOPED AND WILL BE
CENTERED IN THE VCNTY OF THE UPPER GREAT LAKES. COLD AIR
ALOFT/SPRING DAYTIME HEATING AND POTENTIAL OF SHORTWAVES ROTATING
THRU THE AREA WITHIN THE LARGE MID-LEVEL LOW CIRCULATION SUGGEST AT
LEAST SCT SHOWERY PCPN (MOSTLY SNOW BUT SOME RAIN AS WELL DURING
PEAK HEATING) BOTH DAYS WITH BEST COVERAGE IN THE AFTN INLAND FROM
LAKE SUPERIOR WHERE HEATING IS BEST. HIGH TEMPS BOTH DAYS SHOULD BE
IN THE MID 30S TO MID 40S...WARMEST SCNTRL.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z FRIDAY AFTERNOON)
ISSUED AT 125 PM EDT THU APR 16 2015
VFR CONDITIONS WILL CONTINUE FOR THIS FORECAST PERIOD. IT IS
POSSIBLE THERE COULD BE A LIGHT SHOWER OR SPRINKLE AROUND EARLY THIS
EVENING AHEAD OF THE FRONT.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 435 AM EDT THU APR 16 2015
NO WIDESPREAD GALES ARE EXPECTED THROUGH THE FORECAST PERIOD...BUT
THERE WILL BE A FEW PERIODS OF STRONGER WINDS STARTING THIS WEEKEND.
WINDS EXPECTED TO REMAIN AT OR BLO 20 KTS THROUGH FRIDAY NIGHT AS
PRESSURE GRADIENT IS WEAK. HIGH PRESSURE MOVING ACROSS ON SATURDAY
WITH LOW PRESSURE FOLLOWING OVER SCNTRL CANADA ON SUNDAY WILL RESULT
IN SETUP FOR STRONGER EAST-NORTHEAST WINDS TO 30 KTS OVER WESTERN LK
SUPERIOR SATURDAY AND SATURDAY NIGHT. STRONGEST WINDS WILL BE TOWARD
HEAD OF LK SUPERIOR NEAR DULUTH AND SUPERIOR. BY SUNDAY...AS THE LOW
PRESSURE SYSTEM APPROACHES...SOUTHEAST WINDS TO 30 KTS WILL BE
POSSIBLE OVER EASTERN HALF OF LK SUPERIOR WHILE WINDS DIMINISH IN
THE WEST. THE LOW CROSSES THE UPPER GREAT LAKES BY MONDAY WHILE
MERGING WITH ANOTHER LOW LIFTING IN FM THE CENTRAL PLAINS. EXPECT
WEST WINDS UP TO 30 KTS OVER MUCH OF THE LAKE LATER MONDAY INTO
TUESDAY IN WAKE OF THIS COMBINED LOW AS IT MOVES TO THE LOWER GREAT
LAKES.
&&
.HYDROLOGY...
ISSUED AT 332 PM EDT WED APR 15 2015
SEEMS THAT WITHOUT ANY SIGNIFICANT ADDITIONAL PRECIPITATION ADDED TO
THE ONGOING SNOWMELT...AT LEAST FOR THE REST OF THIS WEEK...MAINLY
LOOKING AT A FEW BANKFULL ISSUES ON SOME RIVERS WITH CONTINUATION OF
LOW-END ADVISORIES. BELOW NORMAL TEMPERATURES ARE EXPECTED MONDAY
THROUGH MUCH OF NEXT WEEK...WHICH WILL LIMIT MELTING OF ANY
REMAINING SNOW PACK AND REDUCE RIVER LEVELS.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
UPDATE...JLA
SHORT TERM...JLA
LONG TERM...ROLFSON
AVIATION...TITUS
MARINE...JLA
HYDROLOGY...TITUS
AREA FORECAST DISCUSSION
NWS GRAND RAPIDS MI
1205 PM EDT THU APR 16 2015
LATEST UPDATE...
AVIATION
.SYNOPSIS...
ISSUED AT 310 AM EDT THU APR 16 2015
LIGHT RAIN IS LIKELY TODAY ACROSS MUCH OF SOUTHWEST LOWER MICHIGAN
AS WEAK LOW PRESSURE MOVES NORTH FROM THE GULF. THE SHOWERS WILL
DIMINISH TONIGHT LEADING TO A DRY FRIDAY AND SATURDAY. RAIN IS BACK
IN THE PICTURE LATE IN THE WEEKEND AND EARLY NEXT WEEK AS A STRONGER
LOW MOVES EAST FROM THE PLAINS ACROSS THE GREAT LAKES.
TODAY WILL BE A BIT COOLER THAN WEDNESDAY; WE/LL SEE HIGHS IN THE
50S. TEMPERATURES WILL CLIMB TO AROUND 70 FRIDAY AND SATURDAY BEFORE
COOLER WEATHER DEVELOPS EARLY NEXT WEEK. MUCH OF NEXT WEEK WILL SEE
HIGHS ONLY AROUND 50.
&&
.UPDATE...
ISSUED AT 856 AM EDT THU APR 16 2015
I DID A QUICK UPDATE TO THE POP AND WEATHER GRIDS TO BETTER
REFLECT THE CURRENT RADAR TRENDS. THAT MEANS I INCREASED THE POP
TO NEAR 100 PCT OVER OUR NW CWA AND I HAVE AN AREA OF LOW POP
SOUTHWEST OF GRR (IT IS REALLY THERE) THAT MOVES NORTH WITH TIME.
THE ENTIRE AREA OF SHOWERS SHOULD BE MOSTLY OUT OF OUR CWA BY
MID AFTERNOON AS DRIER AIR MOVES IN AT MID LEVELS. THIS IDEA IS
MOSTLY BASED ON USING THE RAP MODEL LIFT IN THE DGZ WHERE THE AIR
IN THAT LAYER IS SATURATED. AT 8 AM THE AREA OF BEST LIFT IS NEAR
AND WEST OF US-131. BY 2 PM IT IS MOSTLY EAST OF I-75 BUT THERE IS
A SMALL AREA OF STRONG LIFT JUST SOUTH OF GRR AT THAT TIME WHICH
LIFTS TO NEAR LANSING BY 5 PM. THAT WILL HAVE TO BE WATCHED TO SEE
OF AN AREA OF SIGNIFICANT SHOWERS DOES DEVELOP THERE. I STILL EXPECT
NO THUNDERSTORM ACTIVITY TODAY.
&&
.SHORT TERM...(TODAY THROUGH SATURDAY)
ISSUED AT 310 AM EDT THU APR 16 2015
FORECAST CONCERNS DEAL WITH PCPN TRENDS TODAY. OVERALL...THE
FORECAST IS LARGELY ON TRACK ALTHOUGH QPF HAS BEEN TRIMMED A BIT.
00Z SOUNDING AT DTX WAS EXTREMELY DRY BELOW 450 MB AND EXPLAINS WHY
WE HAVEN/T SEEN MUCH RAIN AT THE SFC DESPITE ECHOS ACROSS THE LAKE
SHORE. THE SFC WAVE OF LOW PRESSURE TO THE SOUTH WILL MOVE OVER THE
CWA TODAY AND WE SHOULD SEE THE LOWER LEVELS OF THE ATM MOISTEN AND
RAIN TO DEVELOP. KGRR-88D SHOWS ECHO INTENSITY INCREASING A BIT AS
PCPN CONTINUES TO MOVE NORTH FROM INDIANA. SHORT RANGE NWP SHOWED
THE AREA OF THETA-E DECREASING WITH HEIGHT REMAINING SOUTH OF THE
CWA SO WE OPTED TO GO WITH NO THUNDER IN THE GRIDS TODAY. PCPN WILL
BEGIN TO MOVE EAST THIS AFTERNOON AND END EARLY IN THE EVENING. THIS
WILL LEAD TO A COUPLE OF DRY DAYS FRIDAY AND SATURDAY AS HIGH
PRESSURE NOSES IN FROM ONTARIO.
TEMPS WILL BE HELD DOWN A BIT BY THE SHOWERS TODAY AND WE`LL GO WITH
HIGHS IN THE MID TO UPPER 50S. UPPER HEIGHT RISES ASSOCIATED WITH
THE RIDGE WILL RESULT IN TEMPS AROUND 10 DEGREES WARMER FRIDAY AND
SATURDAY.
.LONG TERM...(SATURDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 310 AM EDT THU APR 16 2015
MODEL GUIDANCE REMAINS CONSISTENT IN SHOWING RAIN MOVING IN ON
SUNDAY WITH THE BEST CHANCE FOR WET WEATHER SUNDAY AFTERNOON AND
EVENING AS A SFC LOW AND UPPER TROUGH AXIS MOVES OVER LOWER
MICHIGAN. THE LOW CUTS OFF AND BECOMES VERTICALLY STACKED NORTH OF
LAKE SUPERIOR ON MONDAY WITH VORT ENERGY ROTATING THROUGH LOWER
MICHIGAN ON TUESDAY AND WEDNESDAY. GIVEN WET BULB ZERO HEIGHTS
CRASHING TO NEAR THE SFC...DO NOT BE SURPRISED TO SEE SOME SNOW
ACROSS AT LEAST THE NORTHERN ZONES TUESDAY THROUGH WEDNESDAY.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z FRIDAY)
ISSUED AT 1205 PM EDT THU APR 16 2015
A MIX OF MVFR AND VFR CONDITIONS WILL CONTINUE THIS AFTERNOON DUE TO
AREAS OF LOW CLOUD COVER. LINGERING LIGHT RAIN SHOWERS AND SPRINKLES
WILL GRADUALLY TAPER OFF THIS AFTERNOON. CONDITIONS SHOULD IMPROVE
TO MAINLY VFR THIS EVENING BUT THE COMBINATION OF PARTIAL CLEARING
AND LIGHT WINDS IN CONJUNCTION WITH LINGERING BOUNDARY LAYER
MOISTURE FROM RAINFALL TODAY WILL RESULT IN POTENTIAL FOR PATCHY FOG
TO DEVELOP OVERNIGHT. ANY FOG SHOULD DISSIPATE BY MID MORNING FRIDAY
WITH VFR CONDITIONS TO FOLLOW FOR THE REST OF THE DAY.
&&
.MARINE...
ISSUED AT 310 AM EDT THU APR 16 2015
EAST WINDS 5 TO 15 KNOTS WILL NOT BE HAZARDOUS TO SMALL CRAFT TODAY.
&&
.HYDROLOGY...
ISSUED AT 1123 AM EDT THU APR 16 2015
THE LONE ADVISORY AT MAPLE RAPIDS CONTINUES TO SHOW IMPROVEMENT.
LIGHTER PRECIPITATION TODAY SHOULD NOT HAVE MUCH OF AN AFFECT ON
THE DROP THAT IS BEING EXPERIENCED. WE SHOULD SEE LEVELS DROP BELOW
ADVISORY CRITERIA LATE THIS EVENING.
BEYOND TWO DRY DAYS...FRIDAY AND SATURDAY...THE PATTERN GETS A BIT
ACTIVE AGAIN. WE COULD SEE SOME BENEFICIAL PRECIPITATION BETWEEN
SUNDAY AND TUESDAY. TOTAL AMOUNTS OVER THE NEXT 7 DAYS ARE NOT TOO
HEAVY. SOME MINOR FLUCTUATIONS MAY RESULT ON AREA RIVERS EARLY
NEXT WEEK...BUT AT THIS POINT I DO NOT SEE ANY REAL CAUSE FOR
CONCERN THROUGH THE PERIOD.
&&
.GRR WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LM...NONE.
&&
$$
UPDATE...WDM
SYNOPSIS...04
SHORT TERM...04
LONG TERM...OSTUNO
AVIATION...LAURENS
HYDROLOGY...JAM
MARINE...04
AREA FORECAST DISCUSSION
NWS HASTINGS NE
1216 PM CDT THU APR 16 2015
.UPDATE...
ISSUED AT 1215 PM CDT THU APR 16 2015
OBVIOUSLY A VERY TRICKY WEATHER PATTERN WE ARE IN FOR THE NEXT FEW
DAYS AS FAR AS TRYING TO "PINPOINT" PRECIP CHANCES/COVERAGE MORE
THAN A FEW HOURS IN ADVANCE. THE FIRST ROUND OF MODEST...MUCH-
NEEDED RAINFALL OF MAINLY 0.20-0.60-INCH THAT TARGETED MAINLY THE
WESTERN CWA OVERNIGHT HAS FADED AWAY/LIFTED NORTH...LEAVING IN ITS
WAKE A SIZABLE AREA OF ONLY SPOTTY LIGHT SHOWERS/PATCHY DRIZZLE
AND EVEN SOME LEGITIMATE MAINLY LIGHT FOG MAINLY OVER WEST-
CENTRAL ZONES.
GENERALLY...HERE ARE THE EXPECTATIONS FOR THE NEXT 12 HOURS OR
SO:
BASED ON LATEST TRENDS IN SHORT TERM MODELS SUCH AS RAP/HRRR
AND 4KM WRF...THE LACK OF LARGE-SCALE FORCING AND CURRENT LIMITED
INSTABILITY...THE MAJORITY OF THE CWA SHOULD MAKE IT THROUGH THE
MID-LATE AFTERNOON HOURS WITH NOTHING MORE THAN A PASSING LIGHT
SHOWER/SPOTTY DRIZZLE. HOWEVER...AS THE NEXT BATCH OF MODEST MID
LEVEL SHORTWAVE ENERGY KICKS NORTHEAST OUT OF THE NORTHEAST
PERIPHERY OF THE PARENT CLOSED LOW CENTERED WELL-SOUTHWEST NEAR
THE 4-CORNERS...GRADUAL DESTABILIZATION SHOULD LEAD TO INCREASING
COVERAGE OF SHOWERS/THUNDERSTORMS THROUGH THE LATE AFTERNOON AND
ESPECIALLY EVENING. INITIALLY...THE GREATEST COVERAGE AND THREAT
FOR STRONG STORMS/ISOLATED SEVERE WEATHER LOCALLY SHOULD TARGET
THE SOUTHWEST 1/3 OF THE CWA...BUT ESPECIALLY KS ZONES.
HOWEVER...THE "MAIN SHOW" FOR A GREATER RISK OF SEVERE STORMS ON
THE REGIONAL SCALE SHOULD LARGELY FOCUS JUST OUTSIDE THE CWA TO
THE SOUTH AND WEST WITHIN WEST-CENTRAL/SOUTHWEST KS...WHERE THE
PRIMARY SPC SLIGHT/ENHANCED RISK AREAS ARE FOCUSED. WITH
INSTABILITY EVEN WITHIN SOUTHERN PORTIONS OF THE LOCAL AREA (BOTH
LOW-LEVEL AND ELEVATED) CURRENTLY EXPECTED TO ONLY REACH UP TO
AROUND 1000 J/KG IN THE PRESENCE OF DEEP LAYER SHEAR AROUND
30-40KT...COULD EASILY SEE A MIX OF MULTICELL AND SEMI-ORGANIZED
SUPERCELL STRUCTURES...WITH LOW-END SEVERE HAIL/WIND CLEARLY THE
MAIN THREATS. WITH LOW-LEVEL EASTERLY FLOW...FAIRLY LOW LCL
HEIGHTS AND VARIOUS MESOSCALE INTERACTIONS POSSIBLE...AT LEAST A
BRIEF LATE AFTERNOON-EVENING TORNADO IS NOT COMPLETELY OUT OF THE
QUESTION IN SOUTHERN ZONES...BUT AGREE WITH SPC THAT THIS
PROBABILITY IS QUITE LIMITED/MAINLY 2 PERCENT AT MOST...AND THUS
WILL REFRAIN FROM EVEN MENTIONING A TORNADO RISK IN THE HAZARDOUS
WEATHER OUTLOOK UNLESS LATER TRENDS SUGGEST OTHERWISE. WHILE THE
MAIN OPPORTUNITY FOR POSSIBLE SEVERE STORMS WILL LIKELY FOCUS
DURING THE TYPICAL 4PM- MIDNIGHT TIME FRAME...AT LEAST A FEW
STRONGER STORMS COULD LINGER /RE-DEVELOP WELL INTO THE
NIGHT...POSSIBLY IN 1 OR MORE ROUNDS. OF COURSE...TIMING THESE
INDIVIDUAL ROUNDS OF CONVECTION AND THE ASSOCIATED BREAKS IN
BETWEEN WILL BE VERY DIFFICULT. ON A POSITIVE NOTE...THINK A
DECENT CHUNK OF THE CWA WILL PROBABLY SEE NEW RAINFALL AMOUNTS OF
0.50-1.00" (AND LOCALLY HIGHER) BY SUNRISE FRIDAY...ESPECIALLY
SOUTHERN/WESTERN ZONES.
TEMP-WISE TODAY...WHILE MOSTLY CLOUDY SKIES SHOULD REMAIN IN
PLACE MOST AREAS...THERE HAVE ALREADY BEEN DECENT BREAKS IN
OVERCAST IN SOUTHWESTERN ZONES...WHICH HAVE THE BEST CHANCE OF
POSSIBLY BREACHING 70. MEANWHILE...MOST OF THE CWA (ESPECIALLY IN
NEBRASKA) IS STILL EXPECTED TO TOP OUT SOMEWHERE IN THE
60S...ALBEIT BARELY-SO IN SOME SPOTS. MORE TO COME WITH MAIN
AFTERNOON DISCUSSION...
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 412 AM CDT THU APR 16 2015
RADAR SHOWS SHOWERS AND THUNDERSTORMS MOVING NORTH/NORTHEAST WITH
DEVELOPMENT ON THE SOUTH END OF THE MAIN CLUSTER OF THUNDERSTORMS.
SURFACE ANALYSIS SHOWS A LOW PRESSURE SYSTEM ACROSS WESTERN KANSAS
WITH A COLD FRONT EXTENDING TO THE NORTH ACROSS NEBRASKA.
AN UPPER LEVEL LOW IN THE IN THE FOUR CORNERS REGION WILL DRIFT
TOWARD THE EAST TODAY AND TONIGHT. IN ADVANCE OF THE UPPER LOW A FEW
WAVES WILL MOVE ACROSS THE AREA THROUGH TONIGHT. THE NAM AND GFS
BOTH SPREAD THE PRECIPITATION ACROSS THE FORECAST AREA THROUGH THE
MORNING HOURS AS THE FIRST OF THE WAVES MOVE THROUGH THE FORECAST
AREA. THE RAP AND THE 4KM WRF BOTH INDICATE THIS INITIAL GROUP OF
THUNDERSTORMS WILL MOVE THROUGH AND ALTHOUGH THERE MAY BE SOME
ISOLATED THUNDERSTORMS AROUND...THERE COULD BE A BREAK THIS MORNING.
HAVE KEPT POPS ACROSS THE AREA...BUT DID LOWER THEM A BIT THIS
MORNING.
THE NEXT WAVE WILL MOVE INTO THE AREA THIS AFTERNOON AND EVENING.
THUNDERSTORMS SHOULD DEVELOP IN WESTERN KANSAS AND SPREAD INTO THE
AREA DURING THE AFTERNOON. LATE AFTERNOON INTO THE EARLY EVENING THE
MUCAPE INCREASES TO NEARLY 2500 J/KG MAINLY ACROSS KANSAS. THIS IS
THE AREA WITH THE BEST CHANCE FOR SOME SEVERE WEATHER. ANOTHER UPPER
LEVEL WAVE PUSHES INTO THE AREA LATE TONIGHT. SHOWERS AND
THUNDERSTORMS ARE EXPECTED ACROSS THE AREA LATE TONIGHT.
.LONG TERM...(FRIDAY THROUGH WEDNESDAY)
ISSUED AT 412 AM CDT THU APR 16 2015
A PAIR OF UPPER LEVEL LOWS FORECAST TO TRACK ACROSS THE SOUTHERN
HALF OF THE COUNTRY WILL BRING SOME SIGNIFICANT CHANCES FOR
BENEFICIAL RAINFALL TO THE REGION OVER THE NEXT WEEK OR SO. THE
FIRST OF THESE LOW PRESSURE SYSTEMS IS CURRENTLY SPINNING ACROSS THE
DESERT SOUTHWEST...AND ALREADY HAVING AN IMPACT ON THE LOCAL
WEATHER. WITH THIS LOW CUT OFF FROM THE MAIN UPPER LEVEL FLOW ACROSS
CANADA...EXPECT VERY SLOW PROGRESSION TOWARDS THE EAST TO RESULT IN
MULTIPLE DAYS OF UNSETTLED WEATHER ACROSS THE REGION.
WITH MOIST SOUTHERLY FLOW AHEAD OF THIS SYSTEM...DEWPOINTS HAVE
SURGED INTO THE 50S ACROSS MUCH OF THE LOCAL AREA AND EXPECT THE
ASSOCIATED INSTABILITY TO HELP AID IN THE FORMATION OF THUNDERSTORMS
BOTH FRIDAY AND SATURDAY. THAT SAID...WITH MUCH BETTER SHEAR TO WORK
WITH ON FRIDAY AFTERNOON/EVENING...THIS APPEARS TO BE THE BEST SHOT
FOR MORE WIDESPREAD STRONG AND POTENTIALLY SEVERE STORMS ACROSS THE
REGION...AND NOT SURPRISINGLY ROUGHLY THE SOUTHERN HALF OF THE
FORECAST AREA IS NOW OUTLOOKED BY SPC. IF REALIZED...THE MAIN
HAZARDS ARE LIKELY TO BE LARGE HAIL AND STRONG WIND GUSTS.
WHILE STILL NOT OUT OF THE QUESTION FOR SATURDAY...ADDITIONAL STRONG
TO MARGINALLY SEVERE THUNDERSTORMS WILL BE POSSIBLE DURING THE
AFTERNOON AND EVENING HOURS...BUT DUE TO DIMINISHED SHEAR
VALUES...THINK THE COVERAGE OF THESE STRONGER STORMS WILL BE MUCH
MORE LIMITED. EVEN SO...WIDESPREAD BENEFICIAL RAINFALL IS
ANTICIPATED FOR THE ENTIRE REGION BOTH DAYS...WITH STORM TOTAL
PRECIPITATION AMOUNTS OVER 2 INCHES EXPECTED TO BE FAIRLY WIDESPREAD
BY THE TIME THE RAINFALL ENDS AND THE RESPONSIBLE LOW PRESSURE
SYSTEM TRACKS EASTWARDS SUNDAY AFTERNOON.
THIS LOW PRESSURE SYSTEM WILL BE SHIFTED EASTWARD BY A FAIRLY STRONG
COLD FRONT FORECAST TO DROP SOUTH ACROSS THE LOCAL AREA SUNDAY. THIS
COLD FRONT WILL BRING SIGNIFICANTLY COOLER TEMPERATURES TO START THE
NEW WORK WEEK WITH POTENTIALLY SOME NEAR FREEZING TEMPERATURES
CURRENTLY FORECAST FOR BOTH MONDAY AND TUESDAY MORNINGS. WHILE
ACTUAL FROST MAY NOT DEVELOP EITHER DAY...THESE COOLER TEMPERATURES
WILL BE SOMETHING TO MONITOR AS SENSITIVE VEGETATION MAY BE
IMPACTED. ADDITIONALLY...WITH STRONG NORTHWESTERLY WINDS BEHIND THIS
FRONT AND DRIER AIR ADVECTING IN FROM THE NORTH...COULD EVENTUALLY
SEE SOME NEAR CRITICAL FIRE WEATHER CONDITIONS REALIZED ACROSS
ROUGHLY THE NORTHWESTERN HALF OF THE LOCAL AREA. BECAUSE BOTH OF
THESE POTENTIAL HAZARDS ARE STILL SEVERAL DAYS OUT AND
MARGINAL...OPTED NOT TO MENTION EITHER OF THESE IN THE MORNING HWO.
THEREAFTER...RAINFALL CHANCES WILL INCREASE MIDWEEK AS ANOTHER UPPER
LEVEL LOW MOVES INTO THE DESERT SOUTHWEST AND MOISTURE INCREASES
ACROSS THE REGION.
&&
.AVIATION...(FOR THE 18Z KGRI/KEAR TAFS THROUGH 18Z FRIDAY)
ISSUED AT 1215 PM CDT THU APR 16 2015
THIS WILL A RATHER CHALLENGING PERIOD REGARDING CEILING/VISIBILITY
TRENDS AND ALSO SHOWER/THUNDERSTORM COVERAGE...AND MODIFICATIONS
TO THESE ELEMENTS IN UPCOMING TAF ISSUANCES BOTH ROUTINE ISSUANCE
AND AMENDMENTS ARE LIKELY. BEAR WITH US...
IN GENERAL HOWEVER...AM EXPECTING CURRENT SUB-VFR CEILINGS AND
PATCHY DRIZZLE RIGHT AWAY EARLY THIS AFTERNOON TO LIFT INTO LOW-
END VFR AT SOME POINT THIS AFTERNOON. WHILE AN MVFR/IFR CEILING
CANNOT BE RULED OUT RETURNING AT SOME POINT THIS
EVENING/TONIGHT...WILL HOLD OFF ON THIS MENTION UNTIL THE LATTER
HALF OF THE PERIOD FOR NOW. AS FOR SHOWER/THUNDERSTORM
CHANCES...WHILE PRECIPITATION IS LIKELY ESPECIALLY TONIGHT AT THE
TERMINALS...DO NOT YET HAVE THE CONFIDENCE TO ADVERTISE PREVAILING
SHOWERS/THUNDERSTORMS DURING ANY GIVEN TIME FRAME...AND THUS WILL
CONTINUE TO CARRY EITHER A VICINITY SHOWER (VCSH)/VICINITY
THUNDERSTORM (VCTS) MENTION UNTIL SOMETHING TRULY SHOWS ITS HAND.
FORTUNATELY...SURFACE WIND TRENDS SEEM REASONABLY STRAIGHTFORWARD
(OUTSIDE OF ANY CONVECTIVE ENHANCEMENT/MODIFICATION OF
COURSE)...WITH A GENERALLY EASTERLY DIRECTION PRIMARILY UNDER 12KT
IN PLACE THE MAJORITY OF THE TIME.
&&
.GID WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
KS...NONE.
&&
$$
UPDATE...PFANNKUCH
SHORT TERM...JCB
LONG TERM...ROSSI
AVIATION...PFANNKUCH
AREA FORECAST DISCUSSION
NWS RALEIGH NC
245 PM EDT THU APR 16 2015
.SYNOPSIS...CHILLY HIGH PRESSURE WILL EXTEND INTO THE CAROLINAS AND
VIRGINIA FROM THE NORTHEAST THROUGH TONIGHT. A WEAK AREA OF LOW
PRESSURE WILL DEVELOP OFF THE SOUTHEAST U.S. COAST TODAY AND DRIFT
NORTHEAST AND AWAY FROM THE REGION ON FRIDAY. WEAK HIGH PRESSURE
WILL EXTEND INTO THE AREA LATE FRIDAY INTO SATURDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 1100 AM THURSDAY...
VERY WELL DEFINED WEDGE FRONT ASSOCIATED WITH A HYBRID COLD AIR
DAMMING EVENT SHOWING UP NICELY IN OBSERVATIONS. TO THE
SOUTHEAST...A COASTAL LOW IS DEVELOPING OFF THE COAST OF SC AND
FURTHER ENHANCING THE WEDGE BOUNDARY. THIS WILL MAKE TEMPERATURE
FORECASTS VERY TRICKY TODAY AS A VERY STRONG GRADIENT WILL BE
PRESENT FROM WEST TO EAST WITH VERY COOL HIGHS IN THE WEST AND
POTENTIALLY QUITE A BIT WARMER HIGHS IN THE EAST. FOR NOW HAVE MID
50S IN THE WEST AND UPPER 60S IN THE EAST BUT BY LATE IN THE
AFTERNOON THIS COULD VERY WELL PAN OUT TO BE LOWER 50S IN THE WEST
AND LOWER TO MID 70S IN THE EASTERN TIER OF COUNTIES. PRECIPITATION
CONTINUES ACROSS THE CENTRAL PIEDMONT AND THE NORTHEASTERN COUNTIES
AIDED BY ISENTROPIC LIFT AND SOME UPPER LEVEL DIVERGENCE AS WE SIT
UNDER THE LEFT EXIT REGION OF A 250 MB JET. PRECIPITATION SHOULD
BEGIN TO TREND DOWNWARD HOWEVER AS ISENTROPIC LIFT WEAKENS AND SOME
VERY DRY MID-LEVEL AIR TO THE NORTHEAST TRIES TO WORK SOUTHWESTWARD
INTO THE CWA. THIS IS VERY EVIDENT ON THE SOUNDINGS WHERE THE KMHX
SOUNDING HAS A 5 DEGREE DEWPOINT DEPRESSION AT 850 MB AND THE KWAL
SOUNDING HAS A 33 DEGREE DEWPOINT DEPRESSION. AS PRECIPITATION MOVES
NORTHEAST...COMPOSITE RADAR SHOWS EVAPORATION OF THE
PRECIPITATION...MOST LIKELY CAUSED BY THE MID LEVEL DRY AIR. AS FAR
AS CONVECTIVE ALLOWING MODELS ARE CONCERNED...ONLY ONE REALLY HAS A
HANDLE OF THE CURRENT MODE OF PRECIP AND THAT IS THE HRRR WHICH
DEPICTS THE CURRENT PATTERN VERY WELL. GOING INTO THIS AFTERNOON THE
RAIN OVER THE CENTRAL PART OF THE CWA PUSHES NORTHEAST AND CHANCES
ELSEWHERE DIMINISH THROUGH THE AFTERNOON TO JUST A FEW PATCHES OF
DRIZZLE OR LIGHT RAIN BY THIS EVENING. CLOUDS SHOULD REMAIN
OVERNIGHT...THUS MODERATING LOWS...MAINLY LOW TO MIDDLE 50S NW TO SE.
&&
.SHORT TERM /FRIDAY THROUGH SATURDAY NIGHT/...
AS OF 245 PM THURSDAY...
FRIDAY SHOULD SEE THE BEGINNING OF A SLOW IMPROVEMENT IN SKY
CONDITION AND TEMPS. DEVELOPING (THOUGH WEAK) NW FLOW IN THE MID-
UPPER LEVELS WILL BEGIN TO SCOUR THE CAD AIR MASS FROM ALOFT.
STILL...RESIDUAL LOW LEVEL MOISTURE WILL REMAIN HIGH ENOUGH TO
PRODUCE EXTENSIVE CLOUDINESS IN THE MORNING WITH SOME PARTIAL BREAKS
DEVELOPING IN THE AFTERNOON. THIS HEATING ALONG WITH THE PASSAGE OF
A WEAK MID LEVEL TROUGH MAY PROVIDE ENOUGH LIFT TO GENERATE AN
ISOLATED SHOWER OR THUNDERSTORM ACROSS CENTRAL NC. TEMPS WILL BEGIN
TO RECOVER FRIDAY THOUGH IF CLOUDS STICK AROUND A LOT LONGER THAN
EXPECTED...MAX TEMPS MAY END UP BEING 3-5 DEGREES COOLER THAN
CURRENTLY FORECAST...ESPECIALLY ACROSS THE NORTHERN PIEDMONT. MAX
TEMPS FRIDAY LOW-MID 70S. FRIDAY NIGHT... PARTIAL CLEARING MAY LEAD
TO THE DEVELOPMENT OF FOGGY CONDITIONS AFTER MIDNIGHT. MIN TEMPS 55-
60. -WSS
SAT/SAT NIGHT: EXPECT DRY WEATHER AND PLENTY OF SUNSHINE SAT. A WEAK
BACKDOOR FRONT WILL DROP THROUGH NC IN THE MORNING... OTHERWISE
WE`LL HAVE SURFACE HIGH PRESSURE OVER THE REGION AND A DRY/SUBSIDING
COLUMN BENEATH MID LEVEL RIDGING. WE MAY GET WARM AND MOIST ENOUGH
IN THE SOUTHEAST FOR POTENTIAL INLAND-MOVING SEA BREEZE
CONVECTION... SO WILL RETAIN THE EXISTING ISOLATED MENTION FOR THE
AFTERNOON. WITH THICKNESSES LIKELY NEARING 20 M ABOVE NORMAL AND
GOOD MIXING EXPECTED... HIGHS IN THE UPPER 70S TO LOWER 80S APPEAR
ATTAINABLE. A STRONG VORTICITY MAX AND WAVE CROSSING NRN NEW ENGLAND
SAT WILL HELP PROPEL A MORE PRONOUNCED BACKDOOR FRONT SOUTHWARD TO
NEAR THE VA/NC BORDER LATE SAT NIGHT... PUSHED BY COOL DENSE HIGH
PRESSURE CENTERED OVER WRN QUEBEC. MODELS DIFFER REGARDING HOW FAR
(IF AT ALL) THE FRONT GETS INTO NE NC... WITH THE GFS A BIT FARTHER
SSW THAN THE NAM/ECMWF. GIVEN THE STRENGTH OF THE PARENT HIGH AND
INTENSITY OF THE NEW ENGLAND WAVE... THINK WE`LL SEE ENOUGH
PENETRATION INTO OUR CWA FOR BRIEFLY LOWER DEWPOINTS AND TEMPS INTO
THE NE CWA. EXPECT LOWS IN THE UPPER 50S TO LOWER 60S EXCEPT MID 50S
FAR NE. THE STRONG LOW CLOSING OFF OVER SASK/MANITOBA AND ATTENDING
TROUGH THROUGH THE DAKOTAS ULTIMATELY PICK UP THE SRN STREAM LOW
OVER THE CENTRAL PLAINS... CULMINATING IN DEEP MID LEVEL TROUGHING
THROUGH CENTRAL NOAM BY DAWN SUNDAY. WHILE WE`RE LIKELY TO SEE
INCREASING CLOUDS FROM THE SW SAT NIGHT WITH ENCROACHING DPVA ALOFT
AND IMPROVING MOIST INFLOW IN THE LOWER LEVELS... ANY LIFT IS TOO
WEAK AND THE COLUMN STILL TOO DRY OVERALL TO SUPPORT ANY PRECIP
THROUGH DAWN SUNDAY. -GIH
&&
.LONG TERM /SUNDAY THROUGH THURSDAY/...
AS OF 245 PM THURSDAY...
SUN-MON NIGHT: A WET AND POTENTIALLY STORMY PERIOD. MID LEVEL FLOW
OVER OUR REGION BECOMES INCREASINGLY CYCLONIC AS THE SLIGHTLY
POSITIVELY TILTED BUT SLOWLY DAMPENING LARGE SCALE TROUGH APPROACHES
FROM THE WSW. AT THE SURFACE... THE ASSOCIATED FRONTAL SYSTEM WILL
OCCLUDE OVER THE UPPER MIDWEST AND GREAT LAKES SUN/SUN NIGHT... WITH
THE BACKDOOR FRONT AROUND THE NC/VA BORDER SLOWLY RETREATING BACK TO
THE NNE AS A WARM FRONT... WHILE THE PRIMARY COLD FRONT EXTENDS FROM
A TRIPLE POINT LOW OVER LOWER MICH DOWN THROUGH THE MID/LOWER MISS
VALLEY. MECHANISMS TO FORCE ASCENT SUCH AS MID LEVEL DPVA... UPPER
DIVERGENCE... AND LOWER LEVEL (850-925 MB) MASS CONVERGENCE WILL BE
STRENGTHENING (ESPECIALLY OVER WRN NC/SW VA) LATE SUN... PERSISTING
THROUGH SUN EVENING AND INTO THE NIGHT... AND MOISTURE WILL BE
ABUNDANT WITH AN INFLUX OF PW VALUES OVER 1.5"... OR WELL OVER 200%
OF NORMAL. GIVEN THIS PLENTIFUL WATER CONTENT AND GOOD LIFT...
TRAINING BANDS OF MODERATE RAIN COULD BRING LOCALIZED FLOODING
PROBLEMS. MODELS CONTINUE TO SLOW DOWN THE ARRIVAL OF THE MID LEVEL
TROUGH AND ITS ACCOMPANYING PRECIP... 6-9 HRS SLOWER THAN YESTERDAY
MORNING`S RUNS... AND WILL CONTINUE TO REFLECT THIS IN THE FORECAST.
WILL RAMP UP POPS TO LIKELY WEST/SMALL CHANCE EAST SUN MORNING...
THEN GO TO CATEGORICAL WEST/GOOD CHANCE EAST SUN AFTERNOON... BEFORE
GOING CATEGORICAL AREAWIDE SUN EVENING/NIGHT. WHILE THE LARGE SCALE
MODELS DON`T DEPICT MUCH INSTABILITY AT ALL SUNDAY WITH PRIMARILY
MOIST ADIABATIC FORECAST PROFILES... I DO HAVE SOME CONCERN ABOUT
POCKETS OF CONVECTION AND AN ISOLATED THREAT OF A QUICK WEAK SPIN-UP
IN OUR FAR NORTHWEST LATE SUNDAY INTO SUNDAY NIGHT... ESPECIALLY
NEAR A WEAK ALONG-FRONT LOW THAT THE GFS/ECMWF DEVELOP OVER SOUTH
CENTRAL VA. UPPER DIVERGENCE REACHES A HEFTY MAXIMUM OVER THE SRN
APPALACHIANS SUN EVENING... WITH A 40-50 KT 850 MB JETLET FROM THE
SSE... AND THE RETREATING BACKDOOR FRONTAL ZONE AND AFOREMENTIONED
LOW COULD PROVIDE A SOURCE FOR ENHANCED LOW LEVEL VORTICITY WITH
FORECAST SOUNDINGS SHOWING A STRONGLY CURVED HODOGRAPH. WILL
CONTINUE TO MONITOR. TOTAL RAINFALL IS LIKELY TO REACH AT LEAST ONE
INCH IN MOST SPOTS THROUGH SUN NIGHT... AND WITH A DEEP WARM LAYER
(LCL TO 0C) NEAR 3.5 KM FAVORING WARM RAIN PROCESSES... LOCALLY
HIGHER TOTALS ARE POSSIBLE. WILL TAPER POPS DOWN MON MORNING WEST TO
EAST AS THE MID LEVEL TROUGH AXIS AND CONVEYOR BELT OF PEAK MOISTURE
PUSHES TO OUR NORTHEAST... PLACING US FULLY IN THE WARM SECTOR WITH
A PUNCH OF MID LEVEL DRY AIR ARRIVING FROM THE SW. ANY HEATING AT
ALL WILL PUSH UP MUCAPE TO 1500-2000 J/KG (AS THE GFS SUGGESTS) MON
AFTERNOON WITH 25-30 KT WSW 850 MB WINDS AND BULK SHEAR NEAR 30-35
KTS. THE SLOWLY LOWERING DYNAMIC FORCING FOR ASCENT MAY LIMIT THE
THREAT OF SEVERE STORMS... BUT STILL EXPECT AT LEAST A FEW STRONG
CELLS... ESPECIALLY IF WE DO INDEED GET SOME HEATING AHEAD OF THE
COLD FRONT. AFTER A DOWNWARD TREND TO RAIN WEST TO EAST IN THE
MORNING... WILL REBOUND WITH SCATTERED SHOWERS AND STORMS MON
AFTERNOON INTO EARLY EVENING. A FEW OF THESE COULD PRODUCE STRONG
GUSTY STRAIGHT LINE WINDS GIVEN INDICATIONS OF A STRAIGHT LINE
HODOGRAPH. HIGHS FROM AROUND 70 NW TO THE MID 70S SE. LOWS AROUND 60
TO THE MID 60S WITH THE FRONT LIKELY NOT COMING THROUGH UNTIL LATE.
TUE-THU: FAIRLY QUIET AND DRY WITH SURFACE HIGH PRESSURE BUILDING IN
FROM THE WEST. LARGE/DEEP MID LEVEL LOW PRESSURE CENTERED OVER AND
NORTH OF THE NRN GREAT LAKES WILL COVER MUCH OF CENTRAL AND EASTERN
NOAM... BRINGING SEASONABLY COOL TEMPS AS IT SITS AND SPINS THROUGH
MID WEEK. WE COULD SEE A QUICK SHOT OF LIGHT PRECIP WITH A FRONT
APPROACHING FROM THE NW WED NIGHT OR THU... HOWEVER OUR MOISTURE
SOURCES WILL REMAIN UNTAPPED AND LIFT APPEARS WEAK... SO THIS SHOULD
AMOUNT TO ONLY LIGHT PRECIP AT MOST... AND WILL KEEP POPS WED
NIGHT/THU BELOW CLIMATOLOGY. TEMPS SHOULD HOLD NEAR OR JUST BELOW
NORMAL THROUGH THE PERIOD. -GIH
&&
.AVIATION /18Z THURSDAY THROUGH TUESDAY/...
AS OF 205 PM THURSDAY...
24 HOUR TAF PERIOD: VARIABLE CONDITIONS ACROSS THE CWA RIGHT NOW AS
PREDOMINANTLY IFR CEILINGS AND MVFR VISIBILITIES HAVE OVERSPREAD THE
SOUTHWESTERN COUNTIES...MVFR CONDITIONS OVER THE NW PIEDMONT ARE
SETTLING BACK IN AND VFR TO THE EAST. WHILE CONDITIONS WILL VARY
THIS AFTERNOON BASED ON CLOUD COVER AND PLACEMENT OF PRECIPITATION
THERE WILL BE AN OVERALL TREND OF IMPROVING IN THE EAST THIS
AFTERNOON AND HOLDING STEADY IN THE WEST WHERE THE CAD WEDGE HAS
MORE INFLUENCE. OVERNIGHT TONIGHT EXPECT CEILINGS TO GO DOWN TO AT
LEAST IFR LEVELS IN MOST LOCATIONS. THIS WILL HAPPEN EARLIER IN THE
WEST AND LATER IN EAST. CONVERSELY...AFTER SUNRISE FRIDAY EXPECT
EASTERN SITES TO RECOVER TO VFR FASTER THAN WESTERN SITES WHICH
COULD HOLD MVFR THROUGH THE END OF THE TAF PERIOD. MOSTLY NNE WINDS
AT THIS TIME AT 5-10 KTS BUT AS COASTAL LOW DEVELOPS OFF OF
NC...BIGGER EASTWARD COMPONENT COMING IN...CURRENTLY NOTED AT KRWI.
BIGGEST THREAT TO CEILINGS OVERNIGHT WILL BE LOW CEILINGS WITH
VISIBILITIES SECONDARY. RAIN SHOULD TAPER OFF AFTER SUNSET. ONCE
THAT HAPPENS SHOULD BE DRY THROUGH THE END OF THE TAF PERIOD.
LONG TERM: RETURN TO MAINLY VFR CONDITIONS FRIDAY AFTERNOON THROUGH
SATURDAY. CHANCE FOR ADVERSE CONDITIONS WITH A COLD FRONT SUNDAY
INTO MONDAY AND THEN IMPROVING CONDITIONS FOR MIDWEEK NEXT WEEK.
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...WSS
NEAR TERM...ELLIS
SHORT TERM...WSS/HARTFIELD
LONG TERM...HARTFIELD
AVIATION...ELLIS
AREA FORECAST DISCUSSION
NWS RALEIGH NC
207 PM EDT THU APR 16 2015
.SYNOPSIS...CHILLY HIGH PRESSURE WILL EXTEND INTO THE CAROLINAS AND
VIRGINIA FROM THE NORTHEAST THROUGH TONIGHT. A WEAK AREA OF LOW
PRESSURE WILL DEVELOP OFF THE SOUTHEAST U.S. COAST TODAY AND DRIFT
NORTHEAST AND AWAY FROM THE REGION ON FRIDAY. WEAK HIGH PRESSURE
WILL EXTEND INTO THE AREA LATE FRIDAY INTO SATURDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 1100 AM THURSDAY...
VERY WELL DEFINED WEDGE FRONT ASSOCIATED WITH A HYBRID COLD AIR
DAMMING EVENT SHOWING UP NICELY IN OBSERVATIONS. TO THE
SOUTHEAST...A COASTAL LOW IS DEVELOPING OFF THE COAST OF SC AND
FURTHER ENHANCING THE WEDGE BOUNDARY. THIS WILL MAKE TEMPERATURE
FORECASTS VERY TRICKY TODAY AS A VERY STRONG GRADIENT WILL BE
PRESENT FROM WEST TO EAST WITH VERY COOL HIGHS IN THE WEST AND
POTENTIALLY QUITE A BIT WARMER HIGHS IN THE EAST. FOR NOW HAVE MID
50S IN THE WEST AND UPPER 60S IN THE EAST BUT BY LATE IN THE
AFTERNOON THIS COULD VERY WELL PAN OUT TO BE LOWER 50S IN THE WEST
AND LOWER TO MID 70S IN THE EASTERN TIER OF COUNTIES. PRECIPITATION
CONTINUES ACROSS THE CENTRAL PIEDMONT AND THE NORTHEASTERN COUNTIES
AIDED BY ISENTROPIC LIFT AND SOME UPPER LEVEL DIVERGENCE AS WE SIT
UNDER THE LEFT EXIT REGION OF A 250 MB JET. PRECIPITATION SHOULD
BEGIN TO TREND DOWNWARD HOWEVER AS ISENTROPIC LIFT WEAKENS AND SOME
VERY DRY MID-LEVEL AIR TO THE NORTHEAST TRIES TO WORK SOUTHWESTWARD
INTO THE CWA. THIS IS VERY EVIDENT ON THE SOUNDINGS WHERE THE KMHX
SOUNDING HAS A 5 DEGREE DEWPOINT DEPRESSION AT 850 MB AND THE KWAL
SOUNDING HAS A 33 DEGREE DEWPOINT DEPRESSION. AS PRECIPITATION MOVES
NORTHEAST...COMPOSITE RADAR SHOWS EVAPORATION OF THE
PRECIPITATION...MOST LIKELY CAUSED BY THE MID LEVEL DRY AIR. AS FAR
AS CONVECTIVE ALLOWING MODELS ARE CONCERNED...ONLY ONE REALLY HAS A
HANDLE OF THE CURRENT MODE OF PRECIP AND THAT IS THE HRRR WHICH
DEPICTS THE CURRENT PATTERN VERY WELL. GOING INTO THIS AFTERNOON THE
RAIN OVER THE CENTRAL PART OF THE CWA PUSHES NORTHEAST AND CHANCES
ELSEWHERE DIMINISH THROUGH THE AFTERNOON TO JUST A FEW PATCHES OF
DRIZZLE OR LIGHT RAIN BY THIS EVENING. CLOUDS SHOULD REMAIN
OVERNIGHT...THUS MODERATING LOWS...MAINLY LOW TO MIDDLE 50S NW TO SE.
&&
.SHORT TERM /FRIDAY AND FRIDAY NIGHT/...
AS OF 317 AM THURSDAY...
FRIDAY SHOULD SEE THE BEGINNING OF A SLOW IMPROVEMENT IN SKY
CONDITION AND TEMPS. DEVELOPING (THOUGH WEAK) NW FLOW IN THE MID-
UPPER LEVELS WILL BEGIN TO SCOUR THE CAD AIR MASS FROM ALOFT.
STILL...RESIDUAL LOW LEVEL MOISTURE WILL REMAIN HIGH ENOUGH TO
PRODUCE EXTENSIVE CLOUDINESS IN THE MORNING WITH SOME PARTIAL BREAKS
DEVELOPING IN THE AFTERNOON. THIS HEATING ALONG WITH THE PASSAGE OF
A WEAK MID LEVEL TROUGH MAY PROVIDE ENOUGH LIFT TO GENERATE AN
ISOLATED SHOWER OR THUNDERSTORM ACROSS CENTRAL NC. TEMPS WILL BEGIN
TO RECOVER FRIDAY THOUGH IF CLOUDS STICK AROUND A LOT LONGER THAN
EXPECTED...MAX TEMPS MAY END UP BEING 3-5 DEGREES COOLER THAN
CURRENTLY FORECAST...ESPECIALLY ACROSS THE NORTHERN PIEDMONT. MAX
TEMPS FRIDAY LOW-MID 70S.
FRIDAY NIGHT..PARTIAL CLEARING MAY LEAD TO THE DEVELOPMENT OF FOGGY
CONDITIONS AFTER MIDNIGHT. MIN TEMPS 55-60.
&&
.LONG TERM /SATURDAY THROUGH WEDNESDAY/...
AS OF 320 AM THURSDAY...
SATURDAY AND SATURDAY NIGHT: MID LEVEL S/W RIDGING WILL LARGELY KEEP
CENTRAL NC DRY ON SATURDAY AND SATURDAY NIGHT. HOWEVER... WITH AND
EASTERLY TO SOUTHEASTERLY SURFACE FLOW DEVELOPING LATE SATURDAY
ALONG WITH DAYTIME HEATING CANT COMPLETELY RULE OUT SOME AFTERNOON
SHOWERS AND STORMS ACROSS FAR EASTERN PORTIONS OF THE AREA WHERE LOW
LEVEL CONVERGENCE MAY BE ENHANCED SOME ALONG PERHAPS A SEABREEZE.
THUS... WILL GO WITH A SLIGHT CHANCE FOR SHOWERS AND STORMS ACROSS
OUR FAR EASTERN COUNTIES FOR SATURDAY AFTERNOON. WITH SKIES NOW
EXPECTED TO BE AT LEAST PARTLY SUNNY AT TIMES WILL RAISE HIGH TEMPS
A DEGREE OR TWO INTO THE UPPER 70S NW TO LOWER 80S SE.
THE LATEST GFS/ECMWF/NAM NOW SHOW THE ONSET OF PRECIP DELAYED A GOOD
6 TO 12 HOURS FROM PREVIOUS FORECASTS. THUS... WILL NOT INTRODUCE
POPS UNTIL CLOSE TO DAYBREAK... FIRST IN THE WEST THEN SPREADING
EAST THROUGH THE DAY ON SUNDAY. WITH INCREASING SOUTHERLY LOW LEVEL
FLOW AND CLOUD COVER ON SATURDAY NIGHT/EARLY SUNDAY MORNING EXPECT
LOW TEMPS WILL ABOVE NORMAL... GENERALLY RANGING FROM THE MID 50S IN
THE FAR NE (WHERE WE MAY SEE SOME CLEARING BRIEFLY WITH THE LOSS OF
HEATING AND PRIOR TO THE INCREASING OF MID AND HIGH LEVEL CLOUDS
COVER) TO GENERALLY NEAR 60 ELSEWHERE.
SUNDAY THROUGH MONDAY NIGHT: GOOD MOISTURE TRANSPORT IS EXPECTED ON
SUNDAY INTO SUNDAY NIGHT AS CLOSED LOW INVOF THE FOUR CORNERS REGION
(CURRENTLY) SHIFT EASTWARD AND OPENS WHILE COMBINING WITH A NORTHERN
STREAM TROUGH TO AMPLIFY THE MID/UPPER LEVEL FLOW ACROSS THE CENTRAL
AND EASTERN PART OF THE COUNTRY LATE WEEKEND INTO EARLY NEXT WEEK.
THIS WILL HELP TO DRIVE A LEAD DEEP MOIST AXIS THROUGH CENTRAL NC
LATE SUNDAY THROUGH EARLY MONDAY MORNING. WITH STRONG SOUTHERLY LOW
LEVEL FLOW WITH THIS SYSTEM AND EXCELLENT MOISTURE TRANSPORT WE
SHOULD SEE A LARGE BAND OF SHOWER/ISOLATED STORMS AND HEAVY RAIN
MOVE THROUGH CENTRAL NC LATE SUNDAY INTO SUNDAY NIGHT... WITH A MAIN
THREAT OF HEAVY RAIN. ALTHOUGH GIVEN THE STRONG LOW LEVEL WIND
FIELDS CAN COMPLETELY RULE OUT AT LEAST A STRONG WIND GUST OR TWO.
BUT GIVEN THE RATHER WEAK INSTABILITY AND POOR DIURNAL TIMING FOR
THE MOST PART ANY SEVERE THREAT SHOULD REMAIN LOW. HIGHS SHOULD BE
COOLER SUNDAY WITH THE INCREASE IN CLOUDS AND EVENTUALLY PRECIP LATE
IN THE DAY...EXPECT HIGHS TO BE IN THE MID TO UPPER 60S NW (WHERE WE
COULD SEE A BRIEF CAD AIRMASS DEVELOP) TO THE MID 70S SE/E (MAYBE
EVEN A FEW UPPER 70S SE). LOWS MONDAY MORNING SHOULD BE WARM FOR
THIS TIME OF YEAR... EXPECT LOWS IN THE LOWER TO MID 60S.
THE MAIN SURFACE COLD FRONT SHOULD MOVE THROUGH THE REGION LATE
MONDAY INTO MONDAY EVENING. WHILE THE STRONGER MID AND LOW LEVEL
FLOW WILL HAVE PUSHED TO THE EAST... WE SHOULD SEE INSTABILITY
INCREASE AS SOME DRIER MID LEVEL AIR WORKS INTO THE AREA FROM THE
SOUTHWEST ON MONDAY MORNING/AFTERNOON. THIS SHOULD HELP TO YIELD AT
LEAST SOME DESTABILIZATION AHEAD OF THE FRONT ON MONDAY RESULTING IN
ISOLATED TO SCATTERED SHOWER AND STORMS MONDAY AFTERNOON/EVENING IN
ADVANCE OF THE FRONT... WITH POSSIBLY A FEW STRONG TO MAYBE SEVERE
STORMS (AS DEEP LAYER SHEAR WILL STILL BE AROUND 25 TO 35 KTS). BEST
CHANCE OF ANY SVR AT THIS TIME (KEEP IN MIND WE ARE STILL A WAYS OUT
IN TIME) WOULD BE ACROSS EASTERN PORTIONS OF THE AREA. HIGHS MONDAY
ARE EXPECTED TO BE IN THE 70S TO LOWER 80S EAST/SOUTHEAST. LOWS
TUESDAY MORNING RANGING FROM THE MID 50S NW TO AROUND 60 SE.
TUESDAY THROUGH WEDNESDAY: DRIER WEATHER IS EXPECTED BEHIND THE
FRONT ON TUESDAY AND WEDNESDAY... WITH A MUCH DRIER AIRMASS
ADVECTING INTO THE REGION. HIGH TEMPS SHOULD BE NEAR NORMAL GENERALLY
IN THE 70S... WITH LOWS IN THE 40S AND 50S.
&&
.AVIATION /18Z THURSDAY THROUGH TUESDAY/...
AS OF 205 PM THURSDAY...
24 HOUR TAF PERIOD: VARIABLE CONDITIONS ACROSS THE CWA RIGHT NOW AS
PREDOMINANTLY IFR CEILINGS AND MVFR VISIBILITIES HAVE OVERSPREAD THE
SOUTHWESTERN COUNTIES...MVFR CONDITIONS OVER THE NW PIEDMONT ARE
SETTLING BACK IN AND VFR TO THE EAST. WHILE CONDITIONS WILL VARY
THIS AFTERNOON BASED ON CLOUD COVER AND PLACEMENT OF PRECIPITATION
THERE WILL BE AN OVERALL TREND OF IMPROVING IN THE EAST THIS
AFTERNOON AND HOLDING STEADY IN THE WEST WHERE THE CAD WEDGE HAS
MORE INFLUENCE. OVERNIGHT TONIGHT EXPECT CEILINGS TO GO DOWN TO AT
LEAST IFR LEVELS IN MOST LOCATIONS. THIS WILL HAPPEN EARLIER IN THE
WEST AND LATER IN EAST. CONVERSELY...AFTER SUNRISE FRIDAY EXPECT
EASTERN SITES TO RECOVER TO VFR FASTER THAN WESTERN SITES WHICH
COULD HOLD MVFR THROUGH THE END OF THE TAF PERIOD. MOSTLY NNE WINDS
AT THIS TIME AT 5-10 KTS BUT AS COASTAL LOW DEVELOPS OFF OF
NC...BIGGER EASTWARD COMPONENT COMING IN...CURRENTLY NOTED AT KRWI.
BIGGEST THREAT TO CEILINGS OVERNIGHT WILL BE LOW CEILINGS WITH
VISIBILITIES SECONDARY. RAIN SHOULD TAPER OFF AFTER SUNSET. ONCE
THAT HAPPENS SHOULD BE DRY THROUGH THE END OF THE TAF PERIOD.
LONG TERM: RETURN TO MAINLY VFR CONDITIONS FRIDAY AFTERNOON THROUGH
SATURDAY. CHANCE FOR ADVERSE CONDITIONS WITH A COLD FRONT SUNDAY
INTO MONDAY AND THEN IMPROVING CONDITIONS FOR MIDWEEK NEXT WEEK.
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...WSS
NEAR TERM...ELLIS
SHORT TERM...WSS
LONG TERM...BSD
AVIATION...ELLIS
AREA FORECAST DISCUSSION
NWS NORMAN OK
334 PM CDT THU APR 16 2015
.DISCUSSION...
THIS DISCUSSION WILL REMAIN FOCUSED ON THE SHORT TERM...
THUNDERSTORM AND PRECIPITATION CHANCES FROM THIS EVENING THROUGH
FRIDAY MORNING...
OVERALL... GUIDANCE HAS DONE A POOR JOB IN HANDLING THE BKN/OVC
LOW/MID STRATUS ACROSS THE BULK OF WRN AND CENTRAL OK AND WRN N TX.
THROUGH 20Z... SOME SCATTERED CLEARING HAS FINALLY STARTED AS MORE
STRATOCU/CLOUD STREETS HAVE DEVELOPED. THIS CLOUD COVER WILL
CONTINUE TO PROMOTE A LACK OF INSTABILITY/BL MIXING ACROSS MOST OF
WRN OK AND WRN N TX... BUT WITH THE RECENT TRANSITION TO STRATOCU...
MIXING MAY FINALLY BE PICKING UP. THE EARLY AFTN CONVECTION ACROSS
FAR NW OK AND INTO THE PANHANDLES APPEARED TO BE DRIVEN BY A FOCUSED
REGION OF ISENTROPIC ASCENT... SUPPORTED BY A NARROW REGION OF 1500
J/KG INSTABILITY AND DIVERGENCE ALOFT GIVEN THE ORIENTATION OF THE
UPPER LVL JET MAX ASSOCIATED WITH THE H500 LOW... WHICH CONTINUES TO
SETTLE OVER THE FOUR CORNERS REGION. THE RECENT SEVERE CONVECTION IN
THE PANHANDLES THAT DEVELOPED OVER THE PAST 1 TO 2 HOURS IS
PRIMARILY FOCUSED ON THE DRYLINE/PSUEDO-FRONTAL BOUNDARY THAT
DEVELOPED EARLIER.
AT THE MOMENT... HOW CONVECTION WILL EVOLVE THROUGH THIS EVENING
REMAINS A CHALLENGE. TRADITIONAL GUIDANCE CONTINUES TO STRUGGLE WITH
HOW TO EVOLVE THE UPPER LOW AND CONVECTION. RECENT MESOSCALE
GUIDANCE IS ABLE TO CATCH ON IN SPURTS... BUT IT STRUGGLES AS WELL.
OVERALL... EXPECT CONVECTION ACROSS THE PANHANDLES TO CONTINUE TO
TRANSITION EASTWARD... HOWEVER... RECENT OBS THROUGH 20Z SUGGEST THE
DRYLINE MAY BE STARTING ITS GRADUAL RETREAT TO THE WEST. WITH THIS
SAID... EXPECT THE SFC TROUGH/FRONT (IF WE CAN CALL IT THAT)... WILL
CONTINUE TO LIFT E/NE INTO WRN OK THIS EVENING... WITH STORMS MOVING
INTO NWRN OK AROUND 5 TO 7PM CDT. THE OVERALL EVOLUTION OF STORMS
APPEAR TO HAVE BEEN CAPTURED ON THE RECENT HRRR (18Z RUN)... BUT THE
TIMING MAY BE LATE... THE 12Z TTU WRF SEEMS TO HAVE A DECENT HANDLE
ON TIMING... AS DOES THE WRF-NMM. NOT TO FOCUS SOLELY ON THE WRN
ACTIVITY... STRONG CONVECTION HAS DEVELOPED ACROSS WEST CENTRAL TX
THIS AFTN. CURRENT THOUGHTS HAVE THIS ACTIVITY LIFTING N/NE INTO WRN
N TX AND THE RED RIVER VALLEY. RECENT MESOSCALE GUIDANCE SEEMS TO
SUGGEST THIS ACTIVITY WILL LESSEN AFTER SUNSET AS IT REMAINS DRIVEN
BY DIURNAL HEATING/INSTABILITY.
AS FOR SEVERE STORMS THIS AFTN/EVENING ACROSS WRN OK/WRN N TX...
STORMS THAT ARE ABLE TO MOVE IN OR DEVELOP WILL RESIDE WITHIN AN
ENVIRONMENT SUPPORTIVE OF LARGE HAIL (GOLF BALLS) AND DAMAGING WINDS
(60-70MPH). SEVERE POTENTIAL WILL WANE WITH ANY SCATTERED CONVECTION
THAT PERSISTS INTO THE OVERNIGHT HOURS EASTWARD INTO CENTRAL OK BY
FRIDAY MORNING. THE TORNADO THREAT OVER THE TX PANHANDLE WILL
DIMINISH AS STORMS MOVE OFF THE DRYLINE AND INTO WRN OK... 0-1KM
HELICITY DECREASES AND THE LACK OF A FOCUSING BOUNDARY DOES NOT BODE
WELL FOR TORNADIC DEVELOPMENT ACROSS WRN OK AT THE MOMENT.
JTK
&&
.PRELIMINARY POINT TEMPS/POPS...
OKLAHOMA CITY OK 59 74 59 77 / 40 50 60 30
HOBART OK 57 75 55 77 / 50 50 50 20
WICHITA FALLS TX 60 77 58 80 / 40 50 50 20
GAGE OK 54 74 51 76 / 70 50 50 20
PONCA CITY OK 58 74 58 75 / 30 60 70 50
DURANT OK 61 77 62 78 / 30 50 60 30
&&
.OUN WATCHES/WARNINGS/ADVISORIES...
OK...NONE.
TX...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS GREEN BAY WI
1250 PM CDT THU APR 16 2015
UPDATED AVIATION PORTION FOR 18Z TAF ISSUANCE
.SHORT TERM...TODAY...TONIGHT...AND FRIDAY
ISSUED AT 257 AM CDT THU APR 16 2015
THE LATEST RAP ANALYSIS AND SATELLITE/RADAR IMAGERY SHOW HIGH
PRESSURE CENTERED OVER THE EAST COAST...BUT WITH A RIDGE AXIS
EXTENDING WEST TO THE WESTERN GREAT LAKES. VERY DRY AIR CONTINUES TO
HOLD ON ACROSS THE REGION...AND DEWPOINTS HAVE STRUGGLED TO RECOVER
OVER CENTRAL AND NORTH-CENTRAL WISCONSIN OVERNIGHT. SOUTHEAST LOW
LEVEL FLOW OVER THE SOUTHERN GREAT LAKES IS SLOWLY VEERING TO MORE
OF A SOUTHERLY DIRECTION...BUT IS STILL TRYING TO PUSH LIGHT SHOWER
ACTIVITY ACROSS SOUTH-CENTRAL LAKE MICHIGAN. THIS IS AHEAD OF A
SHORTWAVE OVER THE IL/IN BORDER. THE BONE DRY AIRMASS AND VEERING
FLOW IS NOT HELPING THESE SHOWERS TO MAKE A WESTWARD JAUNT...AND THE
LATEST MESOMODELS KEEP THESE SHOWERS EAST OF THE MANITOWOC SHORELINE
EARLY THIS MORNING. THIS SHOWER ACTIVITY ALONG WITH FIRE WEATHER
CONDITIONS ARE THE MAIN FORECAST CONCERNS IN THE SHORT TERM.
TODAY...THE SHORTWAVE OVER THE IL/IN BORDER WILL LIFT NE THIS
MORNING AND THEN EAST THIS AFTERNOON AS RIDGING OVER THE GREAT LAKES
FLATTENS. 850MB FLOW WILL CONTINUE TO VERY GRADUALLY VEER THIS
MORNING WHICH COMBINED WITH THE VERY DRY AIR ACROSS THE REGION WILL
GIVE THE LIGHT SHOWER ACTIVITY OVER SOUTHERN LAKE MICHIGAN A SUBTLE
PUSH TO THE EAST. SO WILL KEEP THE DRY FORECAST IN TACT...BUT WILL
INCREASE CLOUD COVER OVER EAST-CENTRAL WISCONSIN TODAY AS 5K-6KFT
CLOUDS OVER NORTHERN ILLINOIS WILL LIKELY ARRIVE THIS MORNING.
ELSEWHERE...A MID-LEVEL DECK OVER MINNESOTA AND IOWA WILL SHIFT TO
THE EAST AND MOVE INTO NORTH-CENTRAL WISCONSIN DURING THE
AFTERNOON. UNTIL THESE CLOUDS ARRIVE...A POCKET OF VERY DRY AIR
WILL REMAIN IN PLACE ACROSS CENTRAL AND NORTH-CENTRAL WISCONSIN.
MIXING WILL NOT BE AS GOOD TODAY DUE TO LIGHTER WINDS ALOFT...BUT
STILL LOWERED DEWPOINTS SINCE THINK WILL STILL BE ABLE TO TAP INTO
SOME OF THE BONE DRY AIR JUST ABOVE THE INVERSION. AS A
RESULT...HAVE DROPPED DEWPOINTS AND HUMIDITIES OVER CENTRAL AND
NORTH-CENTRAL WISCONSIN THIS AFTERNOON. HUMIDITIES COULD FALL
BETWEEN 20-25 PCT. FORTUNATELY...WINDS WILL BE MUCH LIGHTER
TODAY...SO SHOULD NOT SEE A REPEAT OF THE CRITICAL FIRE WEATHER
CONDITIONS. HIGHS MAINLY IN THE MID TO UPPER 60S AWAY FROM LAKE
MICHIGAN.
TONIGHT...A COLD FRONT WILL DECAY AS IT MOVES INTO NORTH-CENTRAL
WISCONSIN LATE. MID-LEVEL CLOUDS WILL CONTINUE TO SPREAD EAST AHEAD
OF THE FRONT...BUT GRADUALLY DISSIPATE IN THE PROCESS. SHOULD
THEREFORE SEE A PARTLY CLOUDY TO MOSTLY CLEAR NIGHT. WITH THE
THINNING CLOUDS...DO NOT THINK THERE WILL BE A DEEP ENOUGH CLOUD
LAYER FOR SPRINKLES OR LIGHT SHOWERS. LOWS MAINLY IN THE LOW TO MID
40S.
FRIDAY...THE FRONT WILL WASH OUT ACROSS NORTHERN WISCONSIN. MAY SEE
SOME CU DEVELOP OVER CENTRAL AND EAST-CENTRAL WISCONSIN DURING THE
AFTERNOON...BUT THE NORTH SHOULD SEE AN INFLUX OF DRY AIR...THAT
WILL DROP HUMIDITIES NEAR 25 PCT IN THE AFTERNOON. HIGHS WILL BE
WARMER THAN TODAYS READINGS...AND RAISED THEM INTO THE UPPER 60S
NORTH TO MID 70S SOUTH.
.LONG TERM...FRIDAY NIGHT THROUGH WEDNESDAY
ISSUED AT 257 AM CDT THU APR 16 2015
DRY CONDITIONS WILL CONTINUE FRIDAY NIGHT AND SATURDAY AS CANADIAN
HIGH PRESSURE BUILDS INTO THE STATE. NORTHWEST WINDS WILL TURN
TO THE EAST AND NORTHEAST LATE FRIDAY NIGHT AND SATURDAY. SATURDAY
AFTERNOON WILL AGAIN FEATURE VERY LOW AFTERNOON RELATIVE HUMIDITY
READINGS AWAY FROM THE LAKE...WITH READINGS DROPPING INTO THE 20
TO 40 PERCENT RANGE WITH THE LOWEST READINGS NORTH AND WEST OF THE
FOX VALLEY.
MEANWHILE...CLOSED UPPER LOW ACROSS THE CENTRAL PLAINS IS EXPECTED
TO OPEN UP AS 500MB TROUGH ACROSS SOUTHERN CANADA WILL BEGIN TO
LIFT THE SOUTHERN SYSTEM NORTHEAST TOWARDS THE REGION. QUIET A
SPREAD IN THE MODELS ON HOW QUICK THE RAIN WILL ARRIVE OVER THE
WEEKEND. THE WRF MODELS WAS QUICKEST...ALREADY BRINGING RAIN ON
SATURDAY TO PORTIONS OF THE AREA. THE GFS MODEL WAS IN THE MIDDLE
OF THE ROAD SOLUTION...WHILE THE CANADIAN/ECMWF MODEL WERE THE SLOWEST
SOLUTION WITH RAIN ARRIVING ON SUNDAY. TRENDED TOWARD THE SLOWER
SOLUTION FOR THE MEANTIME DUE TO BETTER CONSISTENCY FROM RUN TO
RUN. DID ADD A SMALL CHANCE OF RAIN ACROSS THE WEST LATE SATURDAY
NIGHT...AND THEN BOOSTED RAIN CHANCES INTO THE LIKELY CATEGORY ON
SUNDAY. DID RAISE RAIN CHANCES SUNDAY NIGHT AS WELL. THE 500MB
SYSTEMS WILL MERGE INTO A CLOSED UPPER LOW ACROSS THE UPPER
MIDWEST AND WESTERN GREAT LAKES REGION EARLY NEXT WEEK. THIS
WOULD SUPPORT A COOLER AND UNSETTLED PATTERN ACROSS THE REGION
ON MONDAY THROUGH WEDNESDAY. HAVE CHANCES OF SHOWERS EACH PERIOD...
ALONG WITH A LITTLE SNOW LATE AT NIGHT INTO THE EARLY MORNING
HOURS ON TUESDAY AND WEDNESDAY. IT IS WISCONSIN! TEMPERATURES
BY EARLY NEXT WEEK WILL RUN WELL BELOW NORMAL.
&&
.AVIATION...FOR 18Z TAF ISSUANCE
ISSUED AT 1250 PM CDT THU APR 16 2015
VFR CONDITIONS SHOULD PREVAIL THROUGH AT LEAST FRIDAY MORNING.
A CLOUD DECK BELOW 1KFT MOVED INTO THE SOUTHEAST PART OF THE AREA
THIS MORNING BUT MOVED OVER LAKE MICHIGAN BY 17Z. RADAR SHOWED SOME
ECHOES ACROSS PARTS OF CENTRAL/NORTH CENTRAL WISCONSIN DRIFTING TO
THE EAST BUT THEY WERE SCATTERED...SURFACE DEW POINT DEPRESSIONS
WERE IN EXCESS OF 30F...AND MOST OF THE SURFACE OBSERVATIONS IN
THAT PART OF THE STATE DID NOT EVEN INDICATE ANY CLOUDS. MODEL
TIME SECTIONS SHOWED A MOIST LAYER OVERNIGHT IN THE 5KFT-10KFT
RANGE...WITH DECREASING RH IN THAT LAYER AROUND 12Z. THE SURFACE
PRESSURE GRADIENT IS NOT EXPECTED TO BE TIGHT...SO WINDS SHOULD
REMAIN LIGHT.
&&
.GRB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM.....MPC
LONG TERM......ECKBERG
AVIATION.......MG