Forecast Discussions mentioning any of
"HRRR" "RAP" "RR" "RUC13" "RUC" received at GSD on 05/29/14
AREA FORECAST DISCUSSION
NWS TAUNTON MA
946 PM EDT WED MAY 28 2014
.SYNOPSIS...
THE RAW AND DAMP CONDITIONS TODAY GIVE WAY TO A COLD NIGHT ACROSS
THE REGION ALTHOUGH UNDER CLEARING SKIES. DRY WEATHER PREVAILS
TOMORROW AND TOMORROW NIGHT...WITH MORE SUNSHINE DURING THE
DAY...BUT TEMPERATURES ARE EXPECTED TO STILL FALL SHORT OF NORMAL.
A COLD FRONT WILL TRIGGER SCATTERED SHOWERS AND POSSIBLE
THUNDERSTORMS FRI INTO FRI EVENING. COOL SHOWERY WEATHER LINGERS
INTO SAT...THEN A MODERATING TREND FOLLOWS FOR EARLY NEXT WEEK.
&&
.NEAR TERM /UNTIL 6 AM THURSDAY MORNING/...
10 PM UPDATE...MADE MINOR UPDATES TO SKY GRIDS TO ACCOUNT FOR THE
LATEST TRENDS. SKIES ARE STARTING TO CLEAR ACROSS NORTHERN NEW
ENGLAND...WITH THE POSSIBLE EXCEPTION OF THE IMMEDIATE COAST WHERE
LOW CLOUDS REMAIN. EXPECT THIS TREND TO CONTINUE THROUGH SOUTHERN
NEW ENGLAND. OTHERWISE...THE FORECAST REMAINS ON TRACK.
730 PM UPDATE...
CLEARING IS STILL A BIT SLOW TO DEVELOP ACROSS SOUTHERN NEW
ENGLAND. 28/22Z HRRR IS STILL INDICATING CLEARING RAPIDLY
DEVELOPING THIS EVENING...WHICH IS CONSISTENT WITH PREVIOUS
GUIDANCE. KEPT THAT AS THE FORECAST FOR NOW...BUT AM STARTING TO
HAVE SOME DOUBTS ABOUT THAT TIMING. STILL LOOKING AT LOW STRATUS
ACROSS SOUTHERN NEW HAMPSHIRE. THIS WILL NEED TO BE MONITORED.
TEMPERATURES WILL BE SLOW TO CHANGE...BUT DID MAKE SOME TWEAKS TO
BRING NEAR-TERM FORECAST IN LINE WITH OBSERVED TRENDS.
PREVIOUS DISCUSSION...
BASE OF MID LVL SHORTWAVE IS EXPECTED TO SLIDE JUST E OF THE
REGION DURING THE EVENING HOURS...WHICH SHOULD ALLOW THE DRIZZLE
TO GRADUALLY DISSIPATE ACROSS THE REGION FROM N TO S. FOLLOWING
THIS...DRY AIR AND ASSOCIATED SFC HIGH PRES WILL ALLOW FOR GRADUAL
CLEARING FROM N TO S AS WELL. A LOOK AT AFTERNOON SAT IMAGERY
ALREADY SHOWS THIS CLEARING LINE ACROSS PORTIONS OF SRN ME AND NRN
NH. DEWPOINTS ARE ALREADY STARTING TO RESPOND...HAVING DROPPED TO
MAINLY THE LOW-MID 40S FROM CLOSER TO 50 THIS MORNING.
WITH THE CONTINUED DECLINE OF DEWPOINTS...AND THE TREND TOWARD
CLEARING SKIES AND SLACKENING PRES GRADIENT WITHIN THE BUILDING
HIGH PRES FROM THE N...THE LATE OVERNIGHT HOURS FEATURE A GOOD
SETUP FOR RADIATIONAL COOLING. THIS WILL LEAD TO TWO POTENTIAL
ISSUES. WHERE TEMPS ARE ABLE TO COOL FAST ENOUGH TO APPROACH
DROPPING DEWPOINTS /AND WHERE SOME LEFTOVER GROUND MOISTURE
REMAINS/ EXPECT LOCALIZED PATCHY...AND POTENTIALLY EVEN LOCALLY
DENSE GROUND FOG. NOT CONFIDENT ENOUGH IN EXACTLY WHERE THIS MAY
SET UP...BUT IT IS MOST LIKELY CLOSER TO THE S COAST...WHERE
DEWPOINTS ARE LIKELY TO REMAIN ELEVATED THE LONGEST. MAY NEED TO
MONITOR THIS AS THE EVENING PROGRESSES...PARTICULARLY WITHIN AN
HOUR OR SO OF CLEARING SKIES...EVEN FURTHER INLAND.
THE OTHER ISSUE IS THE POTENTIAL FOR SOME PATCHY FROST WHERE
TEMPS MAY MAKE A RUN AT THE MID 30S. THE BEST CHANCE FOR THIS WILL
BE IN EXTREME NW MA AND SW NH WHERE DEEP VALLEYS MAY PROVIDE
ENOUGH RADIATIONAL COOLING TO REACH THESE LEVELS. THERE IS ONE
MAIN MITIGATING FACTOR...THERE MAY BE ENOUGH GROUND MOISTURE TO
PREVENT THE DEVELOPMENT OF FROST AND PREVENT TEMPERATURES FROM
COMPLETELY FALLING OFF. A CALL TO LOCAL COOPS SUGGESTS GROUND IS
STILL PRETTY WET UP THERE RIGHT NOW...SO WILL OPT TO HOLD OFF ON
ANY FROST ADVISORIES WITH THIS UPDATE.
WITH DECENT RADIATIONAL COOLING...TEMPS ARE LIKELY TO FALL INTO
THE MID 30S IN THE NW...TO MID 40S IN THE URBAN CENTERS. THIS PUTS
SOME LOCATIONS AROUND 5 OR SO DEGREES FROM THEIR RECORD LOW TEMPS.
SEE THE CLIMATE SECTION BELOW FOR THE RECORD MINS.
&&
.SHORT TERM /6 AM THURSDAY MORNING THROUGH THURSDAY NIGHT/...
TOMORROW...
HIGH PRES CRESTS ACROSS THE REGION WITH DRY CONDITIONS AND MOSTLY
SUNNY SKIES. H85 TEMPS ARE STILL EXPECTED TO BE AROUND 1-2 STD
DEVIATIONS BELOW NORMAL WITH H92 TEMPS 2-3 STD DEVIATIONS BELOW
NORMAL. THEREFORE...IN SPITE OF THE MOSTLY SUNNY CONDITIONS SFC
TEMPS ARE LIKELY TO REMAIN BELOW NORMAL WITH FULL MIXING ONLY ABLE
TO PRODUCE THE UPPER MID-UPPER 60S /ALTHOUGH A FEW 70S ARE
POSSIBLE IN THE CT VALLEY THANKS TO DOWNSLOPE/. NEAR THE COASTAL
AREAS SEA BREEZES ARE LIKELY TO HOLD TEMPS IN THE UPPER 50S TO LOW
60S. ESPECIALLY GIVEN THE COOL START.
TOMORROW NIGHT...
WINDS SHIFT TO THE S LATE IN THE DAY TOMORROW...ALLOWING FOR
GRADUAL WARMING IN THE MID LEVELS. THIS COMBINED WITH WHAT MAY BE
SOME LEFTOVER CLOUDS FROM AFTERNOON SHOWER/T-STORM DEVELOPMENT
FURTHER TO THE W SHOULD ALLOW TEMPS TO BE A BIT WARMER OVERNIGHT
DESPITE LIGHT FLOW. DRY WX IS LIKELY TO PREVAIL...EXCEPT MAYBE A
LEFTOVER SHOWER IN EXTREME W MA/NH/CT BY MORNING AHEAD OF A COLD
FRONT. MINS LIKELY TO REMAIN IN THE MID-UPPER 40S AND LOW 50S.
&&
.LONG TERM /FRIDAY THROUGH WEDNESDAY/...
HIGHLIGHTS...
* SCATTERED SHOWERS/POSSIBLE THUNDERSTORMS FRI INTO FRI EVENING
* COOL...SHOWERY WEATHER SAT
* DRY WITH MODERATING TEMPERATURES INTO EARLY NEXT WEEK
* POSSIBLE COLD FRONT NEXT TUESDAY
OVERVIEW...28/12Z GUIDANCE CONTINUES TO SHOW VERY GOOD OVERALL
AGREEMENT AMONG THEIR SOLUTIONS INTO MONDAY. DIFFERENCES THEN
BECOME MORE SIGNIFICANT TOWARD THE MIDDLE OF NEXT WEEK. AT THIS
POINT THINKING THE MODEL CONSENSUS IS THE BEST BASIS FOR UPDATING
THIS PORTION OF THE FORECAST...TO MINIMIZE THE DIFFERENCES.
FRIDAY INTO FRIDAY NIGHT...LATEST GUIDANCE CONTINUES TO BUILD A
MID- LEVEL RIDGE ACROSS THE PLAINS AND UPPER MIDWEST...WITH AN
AMPLIFYING MID-LEVEL TROUGH DEVELOPING INTO A CUTOFF LOW NEAR NEW
ENGLAND SOMETIME SATURDAY. THE PRESENCE OF THIS MID-LEVEL TROUGH
WILL MEAN A COLD FRONT SHOULD MOVE ACROSS OUR REGION FROM NORTH TO
SOUTH DURING THIS PERIOD.
MARGINAL INSTABILITY AHEAD OF THIS FRONT INDICATES SOME POTENTIAL
FOR THUNDERSTORMS...BUT THEY SHOULD NOT BE VERY STRONG AS THE
MOST SIGNIFICANT SHEAR REMAINS TO OUR WEST. AS FOR LOCATION...THE
GREATEST RISK WOULD BE ACROSS INTERIOR SOUTHERN NEW ENGLAND...AWAY
FROM THE MARINE LAYER WHICH WILL LIKELY OVERSPREAD AT LEAST
EASTERN MA AND RI. SHOWERS SHOULD SHIFT TO EASTERN NEW ENGLAND
FRIDAY NIGHT AS MODELS SHOW A WAVE DEVELOPING ON THIS FRONT...
WHICH SHOULD ALLOW THE SHOWERS TO PERSIST INTO THE NIGHT.
SATURDAY...
THE CORRESPONDING WEAK LOW PRESSURE TO THE MID-LEVEL TROUGH
DEVELOPS WELL OFFSHORE...BUT KEEPS MOST OF OUR REGION IN A
PERSISTENT EAST TO NORTHEAST FLOW. THIS MEANS BELOW NORMAL
TEMPERATURES WITH SOME SHOWERS POSSIBLE BENEATH THE COLD POOL.
SUNDAY INTO MONDAY...HIGH PRES WILL BE IN CONTROL AS IT MOVES
INTO NEW ENGLAND SUNDAY...THEN SHIFTS TO OUR SOUTH MONDAY. DRY
WEATHER AND MOSTLY SUNNY SKIES EXPECTED...ALTHOUGH MORE CLOUDS ARE
POSSIBLE MONDAY AS A COLD FRONT APPROACHES FROM THE NORTH. THERE
COULD BE A FEW SHOWERS AS WELL. A GRADUAL WARMING TREND IS
LIKELY...WITH THE HIGHEST TEMPERATURES MONDAY...AS WINDS TURN
SOUTHWEST.
TUESDAY...GFS AND ECMWF SIGNALING A NORTH-TO-SOUTH MOVING COLD
FRONT...WITH LOWER TEMPERATURES AND SHOWERS POSSIBLE.
WEDNESDAY...
LOW PRESSURE MOVES INTO THE GREAT LAKES REGION. STILL SOME
UNCERTAINTY WITH THE EXACT TRACK. THE FRONTAL BOUNDARY FROM
TUESDAY SHOULD REMAIN TO OUR SOUTH. THIS SHOULD MEAN LOWER
TEMPERATURES THAN TUESDAY...BUT STILL A CHANCE OF SHOWERS.
&&
.AVIATION /02Z THURSDAY THROUGH MONDAY/...
FORECASTER CONFIDENCE LEVELS...
LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.
THROUGH TONIGHT...HIGH CONFIDENCE IN OVERALL TRENDS. LOWER
CONFIDENCE IN TIMING OF ANY IMPROVEMENT. THE WIDESPREAD MVFR/IFR
CONDITIONS ARE EXPECTED TO HOLD THROUGH ABOUT 29/03Z...AT WHICH
POINT GRADUAL CLEARING FROM N TO S SHOULD ALLOW FOR IMPROVEMENT TO
VFR. THE ONLY CAVEAT MAY BE FOR A BRIEF PERIOD OF CONTINUED
MVFR/IFR AS SOME FOG DEVELOPS DURING FROM ABOUT 00Z-06Z...AFTER
WHICH THIS TOO SHOULD CLEAR THROUGH 12Z. SO THE OVERALL...TREND
WILL BE TOWARD IMPROVEMENT...BUT NOT UNTIL THE OVERNIGHT HOURS.
WINDS REMAIN NE WITH GUSTS 15-25 KT THROUGH ABOUT 03Z...THEN
DIMINISH TO LIGHT AND VRB LATE.
THURSDAY AND THURSDAY NIGHT...HIGH CONFIDENCE.
VFR.
KBOS TAF...HIGH CONFIDENCE IN OVERALL TRENDS...LOWER CONFIDENCE IN
TIMING.
KBDL TAF...HIGH CONFIDENCE IN OVERALL TRENDS...LOWER CONFIDENCE IN
TIMING.
OUTLOOK...FRIDAY THROUGH MONDAY...
FRIDAY...HIGH CONFIDENCE. MAINLY VFR...BUT BRIEF MVFR POSSIBLE
FRIDAY IN SCT SHOWERS AND POSSIBLE TSTMS.
FRIDAY NIGHT INTO SATURDAY...MODERATE CONFIDENCE. AREAS OF MVFR CIGS
AND SCT SHOWERS MAY LINGER INTO SAT.
SUNDAY AND MONDAY...HIGH CONFIDENCE. VFR.
&&
.MARINE...
FORECASTER CONFIDENCE LEVELS...
LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.
THROUGH TOMORROW NIGHT...HIGH CONFIDENCE.
CANCELLED THE SMALL CRAFT ADVISORY FOR BOSTON HARBOR AND
NARRAGANSETT BAY AS WINDS HAVE DIMINISHED TO LESS THAN 25 KT.
NORTHEAST WINDS WITH GUSTS AROUND 25-30 KT WILL CONTINUE THROUGH
THE EVENING HOURS...WITH EVEN THE POSSIBILITY OF A GUST OR TWO TO
GALE FORCE ON THE S OCEAN WATERS. THESE WINDS WILL GRADUALLY
SLACKEN FROM N-S...LIKELY DROPPING BELOW SMALL CRAFT ADVISORY
LEVELS AFTER MIDNIGHT EVERYWHERE. HOWEVER...LINGERING SWELL IS
LIKELY TO TAKE SOME TIME TO SUBSIDE DURING THE OVERNIGHT HOURS AND
INTO THE DAY TOMORROW...SO EXPECT SMALL CRAFT ADVISORIES TO REMAIN
ON OUTSIDE OF BAYS/SOUNDS LATE TONIGHT INTO TOMORROW UNTIL THE
WAVES DROP BELOW 5 FT. ENDING TIME OF SMALL CRAFT ADVISORIES NEAR
SHORE WERE LENGTHENED THIS EVENING...BUT THE TIMING OF THOSE
ENDING TOMORROW LOOKED GOOD.
BY LATE DAY TOMORROW AND TOMORROW NIGHT...HIGH PRES WILL BE MOVING
OVER THE WATERS...ALLOWING FOR A PERIOD OF QUIET BOATING WEATHER.
OUTLOOK...FRIDAY THROUGH MONDAY...
FRIDAY...HIGH PRES WILL RESULT IN LIGHT WINDS AND SEAS.
SATURDAY INTO SATURDAY NIGHT...A PERIOD OF NE WIND GUSTS TO 20-25
KT POSSIBLE ALONG WITH BUILDING SEAS. A SMALL CRAFT ADVISORY MAY
BE NEEDED DURING THIS PERIOD.
SUNDAY AND MONDAY...DIMINISHING WINDS AS HIGH PRESSURE BUILDS
OVER THE WATERS. LEFTOVER EASTERLY SWELL MAY RESULT IN ADVISORY
LEVEL SEAS OVER THE OUTER WATERS.
&&
.CLIMATE...
THE UNSEASONABLY COOL WEATHER WILL ALLOW MINIMUM TEMPERATURES TO
FALL TO AROUND 5 DEGREES OF THE RECORD MINIMUMS FOR THE MORNING OF
5/29. HERE ARE THE RECORD MINIMUMS...
BOS...39...1902
ORH...33...1900
PVD...40...1949
BDL...37...1962
&&
.BOX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
MA...NONE.
NH...NONE.
RI...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 2 AM EDT THURSDAY FOR ANZ231>234.
SMALL CRAFT ADVISORY UNTIL 8 AM EDT THURSDAY FOR ANZ235-237-
250-251.
SMALL CRAFT ADVISORY UNTIL 8 PM EDT THURSDAY FOR ANZ254>256.
&&
$$
SYNOPSIS...BELK/DOODY
NEAR TERM...BELK/DOODY/RLG
SHORT TERM...DOODY
LONG TERM...BELK
AVIATION...BELK/DOODY
MARINE...BELK/DOODY
CLIMATE...
AREA FORECAST DISCUSSION
NWS TAUNTON MA
746 PM EDT WED MAY 28 2014
.SYNOPSIS...
THE RAW AND DAMP CONDITIONS TODAY GIVES WAY TO A COLD NIGHT ACROSS
THE REGION ALTHOUGH UNDER CLEARING SKIES. DRY WEATHER PREVAILS
TOMORROW AND TOMORROW NIGHT...WITH MORE SUNSHINE DURING THE
DAY...BUT TEMPERATURES ARE EXPECTED TO STILL FALL SHORT OF
NORMAL. A COLD FRONT WILL TRIGGER SCATTERED SHOWERS AND POSSIBLE
THUNDERSTORMS FRI INTO FRI EVENING. COOL SHOWERY WEATHER LINGERS
INTO SAT...THEN A MODERATING TREND FOLLOWS FOR EARLY NEXT WEEK.
&&
.NEAR TERM /UNTIL 6 AM THURSDAY MORNING/...
730 PM UPDATE...
CLEARING IS STILL A BIT SLOW TO DEVELOP ACROSS SOUTHERN NEW
ENGLAND. 28/22Z HRRR IS STILL INDICATING CLEARING RAPIDLY
DEVELOPING THIS EVENING...WHICH IS CONSISTENT WITH PREVIOUS
GUIDANCE. KEPT THAT AS THE FORECAST FOR NOW...BUT AM STARTING TO
HAVE SOME DOUBTS ABOUT THAT TIMING. STILL LOOKING AT LOW STRATUS
ACROSS SOUTHERN NEW HAMPSHIRE. THIS WILL NEED TO BE MONITORED.
TEMPERATURES WILL BE SLOW TO CHANGE...BUT DID MAKE SOME TWEAKS TO
BRING NEAR-TERM FORECAST IN LINE WITH OBSERVED TRENDS.
PREVIOUS DISCUSSION...
BASE OF MID LVL SHORTWAVE IS EXPECTED TO SLIDE JUST E OF THE
REGION DURING THE EVENING HOURS...WHICH SHOULD ALLOW THE DRIZZLE
TO GRADUALLY DISSIPATE ACROSS THE REGION FROM N TO S. FOLLOWING
THIS...DRY AIR AND ASSOCIATED SFC HIGH PRES WILL ALLOW FOR GRADUAL
CLEARING FROM N TO S AS WELL. A LOOK AT AFTERNOON SAT IMAGERY
ALREADY SHOWS THIS CLEARING LINE ACROSS PORTIONS OF SRN ME AND NRN
NH. DEWPOINTS ARE ALREADY STARTING TO RESPOND...HAVING DROPPED TO
MAINLY THE LOW-MID 40S FROM CLOSER TO 50 THIS MORNING.
WITH THE CONTINUED DECLINE OF DEWPOINTS...AND THE TREND TOWARD
CLEARING SKIES AND SLACKENING PRES GRADIENT WITHIN THE BUILDING
HIGH PRES FROM THE N...THE LATE OVERNIGHT HOURS FEATURE A GOOD
SETUP FOR RADIATIONAL COOLING. THIS WILL LEAD TO TWO POTENTIAL
ISSUES. WHERE TEMPS ARE ABLE TO COOL FAST ENOUGH TO APPROACH
DROPPING DEWPOINTS /AND WHERE SOME LEFTOVER GROUND MOISTURE
REMAINS/ EXPECT LOCALIZED PATCHY...AND POTENTIALLY EVEN LOCALLY
DENSE GROUND FOG. NOT CONFIDENT ENOUGH IN EXACTLY WHERE THIS MAY
SET UP...BUT IT IS MOST LIKELY CLOSER TO THE S COAST...WHERE
DEWPOINTS ARE LIKELY TO REMAIN ELEVATED THE LONGEST. MAY NEED TO
MONITOR THIS AS THE EVENING PROGRESSES...PARTICULARLY WITHIN AN
HOUR OR SO OF CLEARING SKIES...EVEN FURTHER INLAND.
THE OTHER ISSUE IS THE POTENTIAL FOR SOME PATCHY FROST WHERE
TEMPS MAY MAKE A RUN AT THE MID 30S. THE BEST CHANCE FOR THIS WILL
BE IN EXTREME NW MA AND SW NH WHERE DEEP VALLEYS MAY PROVIDE
ENOUGH RADIATIONAL COOLING TO REACH THESE LEVELS. THERE IS ONE
MAIN MITIGATING FACTOR...THERE MAY BE ENOUGH GROUND MOISTURE TO
PREVENT THE DEVELOPMENT OF FROST AND PREVENT TEMPERATURES FROM
COMPLETELY FALLING OFF. A CALL TO LOCAL COOPS SUGGESTS GROUND IS
STILL PRETTY WET UP THERE RIGHT NOW...SO WILL OPT TO HOLD OFF ON
ANY FROST ADVISORIES WITH THIS UPDATE.
WITH DECENT RADIATIONAL COOLING...TEMPS ARE LIKELY TO FALL INTO
THE MID 30S IN THE NW...TO MID 40S IN THE URBAN CENTERS. THIS PUTS
SOME LOCATIONS AROUND 5 OR SO DEGREES FROM THEIR RECORD LOW TEMPS.
SEE THE CLIMATE SECTION BELOW FOR THE RECORD MINS.
&&
.SHORT TERM /6 AM THURSDAY MORNING THROUGH THURSDAY NIGHT/...
TOMORROW...
HIGH PRES CRESTS ACROSS THE REGION WITH DRY CONDITIONS AND MOSTLY
SUNNY SKIES. H85 TEMPS ARE STILL EXPECTED TO BE AROUND 1-2 STD
DEVIATIONS BELOW NORMAL WITH H92 TEMPS 2-3 STD DEVIATIONS BELOW
NORMAL. THEREFORE...IN SPITE OF THE MOSTLY SUNNY CONDITIONS SFC
TEMPS ARE LIKELY TO REMAIN BELOW NORMAL WITH FULL MIXING ONLY ABLE
TO PRODUCE THE UPPER MID-UPPER 60S /ALTHOUGH A FEW 70S ARE
POSSIBLE IN THE CT VALLEY THANKS TO DOWNSLOPE/. NEAR THE COASTAL
AREAS SEA BREEZES ARE LIKELY TO HOLD TEMPS IN THE UPPER 50S TO LOW
60S. ESPECIALLY GIVEN THE COOL START.
TOMORROW NIGHT...
WINDS SHIFT TO THE S LATE IN THE DAY TOMORROW...ALLOWING FOR
GRADUAL WARMING IN THE MID LEVELS. THIS COMBINED WITH WHAT MAY BE
SOME LEFTOVER CLOUDS FROM AFTERNOON SHOWER/T-STORM DEVELOPMENT
FURTHER TO THE W SHOULD ALLOW TEMPS TO BE A BIT WARMER OVERNIGHT
DESPITE LIGHT FLOW. DRY WX IS LIKELY TO PREVAIL...EXCEPT MAYBE A
LEFTOVER SHOWER IN EXTREME W MA/NH/CT BY MORNING AHEAD OF A COLD
FRONT. MINS LIKELY TO REMAIN IN THE MID-UPPER 40S AND LOW 50S.
&&
.LONG TERM /FRIDAY THROUGH WEDNESDAY/...
HIGHLIGHTS...
* SCATTERED SHOWERS/POSSIBLE THUNDERSTORMS FRI INTO FRI EVENING
* COOL...SHOWERY WEATHER SAT
* DRY WITH MODERATING TEMPERATURES INTO EARLY NEXT WEEK
* POSSIBLE COLD FRONT NEXT TUESDAY
OVERVIEW...28/12Z GUIDANCE CONTINUES TO SHOW VERY GOOD OVERALL
AGREEMENT AMONG THEIR SOLUTIONS INTO MONDAY. DIFFERENCES THEN
BECOME MORE SIGNIFICANT TOWARD THE MIDDLE OF NEXT WEEK. AT THIS
POINT THINKING THE MODEL CONSENSUS IS THE BEST BASIS FOR UPDATING
THIS PORTION OF THE FORECAST...TO MINIMIZE THE DIFFERENCES.
FRIDAY INTO FRIDAY NIGHT...LATEST GUIDANCE CONTINUES TO BUILD A
MID- LEVEL RIDGE ACROSS THE PLAINS AND UPPER MIDWEST...WITH AN
AMPLIFYING MID-LEVEL TROUGH DEVELOPING INTO A CUTOFF LOW NEAR NEW
ENGLAND SOMETIME SATURDAY. THE PRESENCE OF THIS MID-LEVEL TROUGH
WILL MEAN A COLD FRONT SHOULD MOVE ACROSS OUR REGION FROM NORTH TO
SOUTH DURING THIS PERIOD.
MARGINAL INSTABILITY AHEAD OF THIS FRONT INDICATES SOME POTENTIAL
FOR THUNDERSTORMS...BUT THEY SHOULD NOT BE VERY STRONG AS THE
MOST SIGNIFICANT SHEAR REMAINS TO OUR WEST. AS FOR LOCATION...THE
GREATEST RISK WOULD BE ACROSS INTERIOR SOUTHERN NEW ENGLAND...AWAY
FROM THE MARINE LAYER WHICH WILL LIKELY OVERSPREAD AT LEAST
EASTERN MA AND RI. SHOWERS SHOULD SHIFT TO EASTERN NEW ENGLAND
FRIDAY NIGHT AS MODELS SHOW A WAVE DEVELOPING ON THIS FRONT...
WHICH SHOULD ALLOW THE SHOWERS TO PERSIST INTO THE NIGHT.
SATURDAY...
THE CORRESPONDING WEAK LOW PRESSURE TO THE MID-LEVEL TROUGH
DEVELOPS WELL OFFSHORE...BUT KEEPS MOST OF OUR REGION IN A
PERSISTENT EAST TO NORTHEAST FLOW. THIS MEANS BELOW NORMAL
TEMPERATURES WITH SOME SHOWERS POSSIBLE BENEATH THE COLD POOL.
SUNDAY INTO MONDAY...HIGH PRES WILL BE IN CONTROL AS IT MOVES
INTO NEW ENGLAND SUNDAY...THEN SHIFTS TO OUR SOUTH MONDAY. DRY
WEATHER AND MOSTLY SUNNY SKIES EXPECTED...ALTHOUGH MORE CLOUDS ARE
POSSIBLE MONDAY AS A COLD FRONT APPROACHES FROM THE NORTH. THERE
COULD BE A FEW SHOWERS AS WELL. A GRADUAL WARMING TREND IS
LIKELY...WITH THE HIGHEST TEMPERATURES MONDAY...AS WINDS TURN
SOUTHWEST.
TUESDAY...GFS AND ECMWF SIGNALING A NORTH-TO-SOUTH MOVING COLD
FRONT...WITH LOWER TEMPERATURES AND SHOWERS POSSIBLE.
WEDNESDAY...
LOW PRESSURE MOVES INTO THE GREAT LAKES REGION. STILL SOME
UNCERTAINTY WITH THE EXACT TRACK. THE FRONTAL BOUNDARY FROM
TUESDAY SHOULD REMAIN TO OUR SOUTH. THIS SHOULD MEAN LOWER
TEMPERATURES THAN TUESDAY...BUT STILL A CHANCE OF SHOWERS.
&&
.AVIATION /23Z WEDNESDAY THROUGH MONDAY/...
FORECASTER CONFIDENCE LEVELS...
LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.
THROUGH TONIGHT...HIGH CONFIDENCE IN OVERALL TRENDS. LOWER
CONFIDENCE IN TIMING OF ANY IMPROVEMENT. THE WIDESPREAD MVFR/IFR
CONDITIONS ARE EXPECTED TO HOLD THROUGH ABOUT 29/03Z...AT WHICH
POINT GRADUAL CLEARING FROM N TO S SHOULD ALLOW FOR IMPROVEMENT TO
VFR. THE ONLY CAVEAT MAY BE FOR A BRIEF PERIOD OF CONTINUED
MVFR/IFR AS SOME FOG DEVELOPS DURING FROM ABOUT 00Z-06Z...AFTER
WHICH THIS TOO SHOULD CLEAR THROUGH 12Z. SO THE OVERALL...TREND
WILL BE TOWARD IMPROVEMENT...BUT NOT UNTIL THE OVERNIGHT HOURS.
WINDS REMAIN NE WITH GUSTS 15-25 KT THROUGH ABOUT 03Z...THEN
DIMINISH TO LIGHT AND VRB LATE.
THURSDAY AND THURSDAY NIGHT...HIGH CONFIDENCE.
VFR.
KBOS TAF...HIGH CONFIDENCE IN OVERALL TRENDS...LOWER CONFIDENCE IN
TIMING.
KBDL TAF...HIGH CONFIDENCE IN OVERALL TRENDS...LOWER CONFIDENCE IN
TIMING.
OUTLOOK...FRIDAY THROUGH MONDAY...
FRIDAY...HIGH CONFIDENCE. MAINLY VFR...BUT BRIEF MVFR POSSIBLE
FRIDAY IN SCT SHOWERS AND POSSIBLE TSTMS.
FRIDAY NIGHT INTO SATURDAY...MODERATE CONFIDENCE. AREAS OF MVFR CIGS
AND SCT SHOWERS MAY LINGER INTO SAT.
SUNDAY AND MONDAY...HIGH CONFIDENCE. VFR.
&&
.MARINE...
FORECASTER CONFIDENCE LEVELS...
LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.
THROUGH TOMORROW NIGHT...HIGH CONFIDENCE.
CANCELLED THE SMALL CRAFT ADVISORY FOR BOSTON HARBOR AND
NARRAGANSETT BAY AS WINDS HAVE DIMINISHED TO LESS THAN 25 KT.
NORTHEAST WINDS WITH GUSTS AROUND 25-30 KT WILL CONTINUE THROUGH
THE EVENING HOURS...WITH EVEN THE POSSIBILITY OF A GUST OR TWO TO
GALE FORCE ON THE S OCEAN WATERS. THESE WINDS WILL GRADUALLY
SLACKEN FROM N-S...LIKELY DROPPING BELOW SMALL CRAFT ADVISORY
LEVELS AFTER MIDNIGHT EVERYWHERE. HOWEVER...LINGERING SWELL IS
LIKELY TO TAKE SOME TIME TO SUBSIDE DURING THE OVERNIGHT HOURS AND
INTO THE DAY TOMORROW...SO EXPECT SMALL CRAFT ADVISORIES TO REMAIN
ON OUTSIDE OF BAYS/SOUNDS LATE TONIGHT INTO TOMORROW UNTIL THE
WAVES DROP BELOW 5 FT. ENDING TIME OF SMALL CRAFT ADVISORIES NEAR
SHORE WERE LENGTHENED THIS EVENING...BUT THE TIMING OF THOSE
ENDING TOMORROW LOOKED GOOD.
BY LATE DAY TOMORROW AND TOMORROW NIGHT...HIGH PRES WILL BE MOVING
OVER THE WATERS...ALLOWING FOR A PERIOD OF QUIET BOATING WEATHER.
OUTLOOK...FRIDAY THROUGH MONDAY...
FRIDAY...HIGH PRES WILL RESULT IN LIGHT WINDS AND SEAS.
SATURDAY INTO SATURDAY NIGHT...A PERIOD OF NE WIND GUSTS TO 20-25
KT POSSIBLE ALONG WITH BUILDING SEAS. A SMALL CRAFT ADVISORY MAY
BE NEEDED DURING THIS PERIOD.
SUNDAY AND MONDAY...DIMINISHING WINDS AS HIGH PRESSURE BUILDS
OVER THE WATERS. LEFTOVER EASTERLY SWELL MAY RESULT IN ADVISORY
LEVEL SEAS OVER THE OUTER WATERS.
&&
.CLIMATE...
THE UNSEASONABLY COOL WEATHER WILL ALLOW MINIMUM TEMPERATURES TO
FALL TO AROUND 5 DEGREES OF THE RECORD MINIMUMS FOR THE MORNING OF
5/29. HERE ARE THE RECORD MINIMUMS...
BOS...39...1902
ORH...33...1900
PVD...40...1949
BDL...37...1962
&&
.BOX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
MA...NONE.
NH...NONE.
RI...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 2 AM EDT THURSDAY FOR ANZ231>234.
SMALL CRAFT ADVISORY UNTIL 8 AM EDT THURSDAY FOR ANZ235-237-
250-251.
SMALL CRAFT ADVISORY UNTIL 8 PM EDT THURSDAY FOR ANZ254>256.
&&
$$
SYNOPSIS...BELK/DOODY
NEAR TERM...BELK/DOODY
SHORT TERM...DOODY
LONG TERM...BELK
AVIATION...BELK/DOODY
MARINE...BELK/DOODY
CLIMATE...STAFF
AREA FORECAST DISCUSSION
NWS NEW YORK NY
154 PM EDT TUE MAY 27 2014
.SYNOPSIS...
A BACK DOOR COLD FRONT APPROACHES FROM THE NORTH...THEN CROSSES
THE TRI-STATE LATE THIS AFTERNOON AND THIS EVENING. THE FRONT
STALLS TO THE SOUTH OF LONG ISLAND WITH WAVES OF LOW PRESSURE
RIDING ALONG IT INTO WEDNESDAY...AS HIGH PRESSURE BEGINS TO BUILD
DOWN FROM SOUTHEASTERN CANADA. THIS HIGH BUILDS DOWN OVER THE AREA
THROUGH THURSDAY NIGHT...THEN SLIDES TO THE EAST FRIDAY. A COLD
FRONT CROSSES THE AREA FRIDAY NIGHT. ANOTHER HIGH PRESSURE THEN
BUILDS ACROSS THE REGION FOR THE WEEKEND. A COLD FRONT APPROACHES
FROM THE WEST NEXT MONDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
THE COMBINATION OF AN APPROACHING BACKDOOR COLD FRONT AND
MULTIPLE FAST MOVING 700 AND 500 HPA SHORTWAVES CROSSING THE AREA
IN NW FLOW ALOFT WILL BRING SCT TO NUMEROUS SHRA WITH A CHANCE OF
THUNDERSTORMS TO THE TRI- STATE THIS AFTERNOON INTO THE EARLY
EVENING. LATEST RADAR REFLECTIVITY ALREADY SHOWING SHOWERS
POPPING UP OVER NW AREAS...WHICH LATEST HRRR RUN SEEMS TO BE
CAPTURING. USING AS SUCH...THE PCPN CONTINUES TO LOOK TO DIVE SE
THROUGH THE REMAINDER OF THE AFTN...WITH THE BEST CHC FOR HEAVIER
SHOWERS/STRONGER TSTMS BETWEEN 20 AND 00Z.
WITH ON AVERAGE 1000-1500 J/KG OF CAPE WITH 25-35 KT OF 0-6KM
SHEAR COULD SEE A FEW ISOLD SUPER CELLS AS WELL AS SOME
MULTI CELLULAR CLUSTERS WHICH ARE STRONG TO POSSIBLY SEVERE. MAIN
FOCUS WILL BE ACROSS NE NJ/NYC METRO/LOWER HUDSON VALLEY/SW
CT...AHEAD OF THE COLD FRONT AND SE SINKING BROAD WEAK LOW. MAIN
THREAT IS LARGE HAIL AND DAMAGING WINDS. SEE HYDROLOGY SECTION
FOR FLOODING THREAT DUE TO CONVECTION AND MOISTURE POOLING AHEAD
OF THE FRONT.
SEVERE THREAT SHOULD END WITH PASSAGE OF THE COLD FRONT ACROSS
EASTERN SECTIONS BETWEEN 20Z AND 23Z...WHILE FARTHER WEST THE
THREAT WILL DIMINISH IN THE EVENING WITH LOSS OF DAYTIME
INSTABILITY. BACKDOOR COLD FRONT SHOULD PASS WEST OF ENTIRE AREA
BY AROUND MIDNIGHT.
SCT SHRA SHOULD LINGER BEHIND THE FRONT TONIGHT IN RESPONSE TO A
PASSING 700-500 HPA SHORTWAVE.
FOR LOWS TONIGHT...USED A BLEND OF NAM 2-METER TEMPERATURES WITH
MAV/MET GUIDANCE...WITH VALUES FORECAST TO BE AROUND 5 DEGREES
ABOVE NORMAL.
&&
.SHORT TERM /WEDNESDAY/...
SHOULD SEE THINGS DRY OUT FROM E TO W AS HIGH PRESSURE BUILDS DOWN
FROM SE CANADA DRYING OUT LOW LEVELS...SO WOULD EXPECT ISOLD-SCT
SHRA TO COME TO AN END DURING THE MORNING ACROSS EASTERN
ZONES...AND BY EARLY AFTERNOON OVER WESTERN ZONES. CLEARING WILL
BE A BIT SLOWER TO OCCUR...SO WOULD EXPECT MOST AREAS TO BE CLOUDY
THROUGH THE DAY...THOUGH COULD SEE SOME BREAKS IN THE CLOUDS BY
LATE AFTERNOON ACROSS THE NE 1/4 OF THE CWA.
WITH THE CLOUD COVER AND A ONSHORE ENE-NE LOW LEVEL
FLOW...HIGHS WEDNESDAY WILL BE AROUND 20 DEGREES COOLER THAN THOSE
ON TODAY...WITH MOST AREAS IN THE LOWER-MID 60S - AROUND 10
DEGREES BELOW NORMAL. THIS IS CONSISTENT WITH A BLEND OF MIXING
DOWN FORM 925 HPA PER BUFKIT SOUNDINGS...NAM 2-METER TEMPERATURES
AND A BLEND OF MAV/MET GUIDANCE.
&&
.LONG TERM /WEDNESDAY NIGHT THROUGH MONDAY/...
AS THE COLD FRONT PUSHES FARTHER SOUTH AND HIGH PRESSURE CONTINUES
TO NOSE INTO THE AREA WEDNESDAY NIGHT INTO THURSDAY...A GOOD AMOUNT
OF CLEARING SHOULD TAKE PLACE. SOME LOW-LEVEL CLOUD COVER WILL
REMAIN ON THURSDAY MORNING ACROSS SOUTHERN PORTIONS OF THE CWA...AS
SOME LEFTOVER MOISTURE TRAPPED UNDER AN INVERSION BENEATH H9 IS
SLOWLY SCOURED OUT. REGARDLESS...THE TREND WILL BE FOR INCREASING
SUNSHINE. MORE INSOLATION DURING THE DAY WILL BE BALANCED BY
COOL ONSHORE FLOW DUE TO THE BUILDING HIGH PRESSURE...YIELDING HIGH
TEMPS BELOW NORMAL.
THE TRI-STATE FINDS ITSELF UNDER THE INFLUENCE OF INCREASING
CYCLONIC H5 FLOW THURSDAY NIGHT INTO FRIDAY...WITH AN APPROACHING
SHORTWAVE AND ASSOCIATED JET STREAK HEADING INTO FRIDAY MORNING. AS
A RESULT...CHANCES FOR SHOWERS AND THUNDERSTORMS
DEVELOP...ESPECIALLY ACROSS THE INTERIOR WHERE THE BEST
JUXTAPOSITION OF COOLING ALOFT/SURFACE HEATING WILL EXIST...YIELDING
A BETTER THERMODYNAMIC PROFILE FOR CONVECTION DURING THE
AFTERNOON/EVENING. A COLD FRONT THEN PUSHES THROUGH THE ENTIRE AREA
FRIDAY NIGHT...INCREASING THE CHANCE FOR PRECIP ACROSS THE REMAINDER
OF THE AREA.
WITH THE CONTINUATION OF CYCLONIC FLOW ACROSS THE AREA ON
SATURDAY...A FEW SHOWERS AND STORMS MAY DEVELOP DURING THE AFTERNOON
AND EVENING ACROSS EASTERN PORTIONS OF THE AREA...WHERE THE BEST
SYNOPTIC SUPPORT WILL EXIST DURING PEAK HEATING.
HIGH PRESSURE THEN BUILDS INTO THE AREA ON SUNDAY WITH TEMPERATURES
CONTINUING TO MODERATE...AS RIDGING ALOFT BUILDS AND HEIGHTS RISE.
BY MONDAY...SW FLOW WILL LEAD TO MANY LOCATIONS LIKELY RISING
SLIGHTLY ABOVE NORMAL FOR HIGHS.
&&
.AVIATION /18Z TUESDAY THROUGH SUNDAY/...
A COLD FRONT APPROACHES FROM THE NORTH LATE TODAY AND MOVES SOUTH
ACROSS THE AREA TONIGHT.
VFR INTO THE AFTERNOON. SHOWERS AND SCATTERED THUNDERSTORMS ARE
EXPECTED TO DEVELOP THIS AFTERNOON ACROSS THE REGION. SOME OF THE
THUNDERSTORMS MAY IMPACT THE TERMINALS AFTER BETWEEN 18Z-22Z WITH
CONDITIONS BRIEFLY LOWERING TO MVFR. A FEW STORMS AROUND NYC AND
NW OF NYC TERMINALS COULD PRODUCE STRONG GUSTY WINDS AND HEAVY
RAINFALL. SHOWERS WILL REMAIN SCATTERED INTO THE EVENING AND
OVERNIGHT HOURS.
WIND WILL BE FROM THE WEST-SOUTHWEST THROUGH THE AFTERNOON. SPEEDS
WILL BE 10 TO 15 KT. WINDS SHIFT BEHIND THE COLD FRONT LATE THIS
AFTERNOON FURTHER EAST...AND THIS EVENING ACROSS NYC METRO
TERMINALS. BEHIND THE FRONT...EXPECT WINDS TO BECOME MORE EAST-
NORTHEAST.
CIGS WILL FALL TO MVFR OR IFR CEILINGS BEHIND THE FRONT...MAINLY
AFTER 07Z.
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)
KEWR FCSTER COMMENTS: WESTERLY WINDS EXPECTED TODAY. AMENDMENTS FOR
POSSIBLE LATE DAY SHOWERS OR THUNDERSTORMS.
KJFK FCSTER COMMENTS: SOUTHWEST-SOUTH WINDS THIS AFTERNOON.
AMENDMENTS FOR POSSIBLE LATE DAY SHOWERS OR THUNDERSTORMS.
KLGA FCSTER COMMENTS: WESTERLY-SOUTHWEST WINDS TODAY. AMENDMENTS
FOR POSSIBLE LATE DAY SHOWERS OR THUNDERSTORMS.
KTEB FCSTER COMMENTS: WESTERLY WINDS EXPECTED TODAY. AMENDMENTS FOR
POSSIBLE LATE DAY SHOWERS OR THUNDERSTORMS.
KHPN FCSTER COMMENTS: MAINLY WESTERLY WINDS TODAY...ALTHOUGH A
SLIGHT SHIFT TO THE SOUTHWEST IS POSSIBLE THIS AFTERNOON. AMENDMENTS
FOR POSSIBLE LATE DAY SHOWERS OR THUNDERSTORMS.
KISP FCSTER COMMENTS: WESTERLY WINDS SHOULD BACK TO THE SOUTHWEST OR
EVEN SOUTH THIS AFTERNOON. AMENDMENTS FOR POSSIBLE LATE DAY SHOWERS
OR THUNDERSTORMS.
.OUTLOOK FOR 18Z WEDNESDAY THROUGH SUNDAY...
.WED AFTERNOON...IMPROVING CIGS DURING THE AFTERNOON. POSSIBLE
SHOWERS.
.WED NIGHT-THU NIGHT...VFR.
.FRI...VFR. SHRA POSSIBLE.
.SAT...VFR.
.SUN...VFR.
&&
.MARINE...
WINDS 10 KT OR LESS OVER THE WATERS THROUGH THIS EVENING. WINDS
INCREASE LATE TONIGHT IN THE WAKE OF A PASSING COLD FRONT. THIS
WILL BUILD SEAS TO SCA LEVEL ACROSS ANZ350-353 AFTER
MIDNIGHT...AND BRING GUSTS TO 25-30 KT TO ALL WATERS WEDNESDAY.
EXPECT WIND GUSTS TO LINGER INTO WEDNESDAY NIGHT ACROSS THE
COASTAL OCEAN WATERS AND S SHORE BAYS. AS A RESULT CONTINUING THE SCA
FROM 04Z WEDNESDAY-10Z THURSDAY FOR ANZ-350-353...FROM 10Z
WEDNESDAY-10Z THURSDAY FOR ANZ-355-3445...AND FROM 10Z-2Z
WEDNESDAY FOR THE REMAINDER OF THE WATERS. THERE IS SOME
POSSIBILITY THAT SCA LEVEL GUSTS COULD LINGER ON THE REMAINDER OF
THE WATERS INTO WEDNESDAY NIGHT...BUT THE CONFIDENCE IN THIS IS
NOT HIGH ENOUGH TO WARRANT HEADLINES THEN IN THOSE ZONES.
ALTHOUGH GUSTS LOOK TO FALL BELOW 25 KT BY THURSDAY
MORNING...SEAS MAY LINGER AROUND 5 FT INTO PART OF THE DAY ON THE
OCEAN. SUB-SCA CONDITIONS WILL EVENTUALLY DEVELOP EVERYWHERE
THOUGH AND REMAIN THAT WAY INTO THE FIRST PART OF SATURDAY.
&&
.HYDROLOGY...
WITH PRECIPITABLE WATERS INCREASING TO 1.5 TO 1.75 INCHES BY THIS
AFTERNOON AND LINGERING INTO THIS EVENING AHEAD OF COLD
FRONT...MINOR URBAN/POOR DRAINAGE FLOODING IS POSSIBLE WITH ANY
CONVECTION THIS AFTERNOON/EVENING. WITH 20-25 KT STEERING
FLOW...FLASH FLOOD THREAT SHOULD BE LOCALIZED TO AREAS UNDER
TRAINING CONVECTION.
OUTSIDE OF A CHANCE OF A FEW TENTHS TO 2/3 INCH BASIN WIDE
RAINFALL THIS AFTERNOON-WEDNESDAY...NO WIDESPREAD SIGNIFICANT
RAINFALL IS EXPECTED THROUGH THE UPCOMING WEEKEND.
&&
.TIDES/COASTAL FLOODING...
A STRENGTHENING ENE-NE FLOW AND NEW MOON WILL PRESENT POTENTIAL FOR
LOCALIZED MINOR COASTAL FLOODING DURING THE TIMES OF HIGH TIDE
WEDNESDAY NIGHT. THE LOWEST LYING COASTAL AREAS ALONG WESTERN
SOUTH SHORE BAYS AND WESTERN LI SOUND WILL BE BE MOST SUSCEPTIBLE.
&&
.OKX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...NONE.
NJ...NONE.
MARINE...SMALL CRAFT ADVISORY FROM 6 AM TO 6 PM EDT WEDNESDAY FOR
ANZ330-335-338-340.
SMALL CRAFT ADVISORY FROM MIDNIGHT TONIGHT TO 6 AM EDT
THURSDAY FOR ANZ350-353.
SMALL CRAFT ADVISORY FROM 6 AM WEDNESDAY TO 6 AM EDT THURSDAY
FOR ANZ345-355.
&&
$$
SYNOPSIS...MALOIT/PICCA
NEAR TERM...SEARS
SHORT TERM...MALOIT
LONG TERM...PICCA
AVIATION...BC
MARINE...MALOIT/PICCA
HYDROLOGY...MALOIT/PICCA
TIDES/COASTAL FLOODING...
AREA FORECAST DISCUSSION
NWS ALBANY NY
114 PM EDT TUE MAY 27 2014
.SYNOPSIS...
A COLD FRONT WILL PUSH SOUTH THROUGH THE REGION TODAY AND
TONIGHT...TRIGGERING A ROUND OF SHOWERS AND THUNDERSTORMS. LATE
WEDNESDAY AND THURSDAY HIGH PRESSURE WILL BUILD OVER THE NORTHEAST WITH
SEASONABLE TEMPERATURES. THURSDAY NIGHT AND FRIDAY ANOTHER COLD
FRONT AND A MID LEVEL WEATHER DISTURBANCE WILL PUSH THROUGH WITH
UNSETTLED WEATHER. HIGH PRESSURE WILL BUILD ALONG THE EASTERN
SEABOARD BY LATE IN THE WEEKEND.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 1230 PM EDT...A SERIES OF COLD FRONTS REMAIN SET UP CLOSE
TO THE REGION...WITH A BACKDOOR BOUNDARY STRETCHING FROM THE NORTH
COUNTRY OF NEW YORK TOWARDS CENTRAL NEW ENGLAND...AND ANOTHER
FRONTAL BOUNDARY EXTENDING SOUTHWEST ACROSS ONTARIO. THESE COLD
FRONTS WILL SLOWLY DRIFT SOUTHWARD TOWARDS OUR AREA
TODAY...SETTING OFF SOME AFTERNOON SHOWERS AND THUNDERSTORMS.
SHOWERS FROM EARLIER THIS MORNING HAVE WEAKENED AND MOVED EASTWARD
INTO NEW ENGLAND...LEAVING DRY WEATHER IN ITS WAKE. THERE HAVE
BEEN BREAKS IN THE CLOUDS...ALLOWING FOR TEMPS TO WARM QUICKLY WITH
DEWPOINTS GENERALLY IN THE 50S. AS TEMPS WARM INTO THE UPPER 70S
TO LOW 80S...CONVECTIVE CU CLOUDS WILL DEVELOP ACROSS THE
REGION...WITH SOME SHOWERS/THUNDERSTORMS DEVELOPING AS EARLY AS
NOON-2 PM. THE LATEST 3KM HRRR SHOWS MAINLY DISORGANIZED ACTIVITY
ACROSS OUR AREA...WITH THE MOST CONCENTRATION OF
SHOWERS/THUNDERSTORMS OVER THE ADIRONDACKS/SRN VT /CLOSER TO THE
BACKDOOR BOUNDARY/ AND ACROSS CENTRAL NY AND EVENTUALLY SPILLING
INTO THE CATSKILLS AND MID HUDSON VALLEY BY LATE THIS AFTN INTO
THIS EVENING...AS THE BEST MOISTURE/INSTABILITY AXIS WILL BE JUST
WEST OF OUR AREA.
SPC HAS OUR AREA IN /SEE TEXT/ FOR SEVERE WEATHER...AS AN
ISOLATED SEVERE STORM CANNOT BE RULED OUT. WITH FZL LEVEL/-20
DEGREE C HEIGHTS HIGHER THAN LAST WEEK...AND MID LEVEL LAPSE RATES
NOT OVERLY IMPRESSIVE...IT WILL BE TOUGH FOR MANY OF THE STORMS
TO BE ABLE TO PRODUCE LARGE HAIL. STILL...SMALL HAIL...HEAVY
DOWNPOURS...AND GUSTY WINDS MAY ACCOMPANY ANY STORM...AND THIS
WORDING WILL BE STRESSED IN THE GRIDS AND HWO STATEMENT.
HIGHS TODAY IN THE 80 TO 85 RANGE...BUT MID TO UPPER 70S HIGHER
TERRAIN. THE COLD FRONT SHOULD TRACK THROUGH TONIGHT BUT COLD
ADVECTION IS RATHER GRADUAL...SO LOWS IN THE 55 TO 60 DEGREE RANGE
BUT LOWER 50S HIGHER TERRAIN. COVERAGE OF SHOWERS SHOULD DECREASE
TO SCATTERED TO ISOLATED LATER AT NIGHT AND EARLY TOMORROW
MORNING...WITH THE THREAT FOR THUNDER DIMINISHING GREATLY AFTER
SUNSET THIS EVENING.
&&
.SHORT TERM /WEDNESDAY THROUGH FRIDAY NIGHT/...
THIS PERIOD WILL BE DOMINATED BY A FAST NW FLOW AT 500HPA...AS A
PARADE OF SHORT WVS PASSES THROUGH THE REGION...EACH SHARPENING A
500HPA TROF OVER NEW ENG...WHILE A SUBSTANTIAL 500HPA RIDGE BUILDS
IN THE UPR GRT PLAINS AND SHIFTS INTO THE GRTLKS. GENERALLY THE
MDL SUITE IS IN AGREEMENT DURING THIS PERIOD.
THE 1ST CDFNT IS ALONG I-80 WED MRNG....AND SAGGING S AS HIGH
PRESSURE BUILDS FM MARITIMES INTO NE USA IN INCRG E-SE MARINE
LAYER FLOW. AT SAME TIME ONE SHORT WV IS MVNG THRU FCA IN NW FLOW.
RESULT WILL BE CONSIDERABLE CLOUDS WED...DCRNG IN AFTN...AND THE
THREAT OF SCT -SHRA IN THE MRNG. TEMPS WILL COOL CONSIDERABLY FM
MON/TUES AS FCA IS IN MARITIME FLOW OFF GULF OF MAINE.
WED NT/THU 500HPA FLOW IS NW...WE TAKE A BREAK FM SHORT WV PARADE
AND SFC HIGH BUILDS INTO NEW ENG AND NY WITH GENERALLY FAIR...DRY
AND SLIGHTLY BLO NORMAL TEMPS. MINS WED NT WILL BE IN THE
40S...HIGHS THU IN THE UPPER 60S AND 70S.
THU NT A STRONG 500 HPA SHORT WV DIVES FM OTTAWA VLY INTO THE
NE...AS ITS CDFNT REACHES THE ST LAWRENCE VLY BY FRI MRNG. THESE
SYSTEMS TRANSIT FCA FRI AND FR NT WITH INCR THREAT OF -SHRA/SCT
TSTMS LATE THU N...AND ACROSS FCA FRI AND FRI NT WHEN 500HPA
TEMPS FALL TO -20C...AND A STRONG DIURNAL ASPECT AS ALMOST SUMMER
SOLSTICE SUN DURING THE DAY FRI. TEMPS WILL BE NR TO SLIGHTLY BLOW
NORMAL TO END THIS PERIOD.
&&
.LONG TERM /SATURDAY THROUGH TUESDAY/...
WHILE THE MDL SUITE IS IN AGREEMENT WITH THE GENERAL PATTERN OF A
SHARP 500HPA TROF JUST OFF THE US EAST COAST...AND A SHARP OR
CLOSED 590 HPA HIGH OVER GRTLKS AND MIDWEST...WITH FCA BWTN THESE
SYSTEMS SAT...AND A GENERALLY SHIFT TO THE EAST TO END THE EFP.
THE QUESTION IS HOW MUCH CLOUDINESS...MARINE LAYER AIR AND
POSSIBLY A 500HPA CUTOFF WILL IMPACT THE FCA. THE ECMWF/HPC/GFS/GEM
TEND TO KEEP BULK OF THE TROF AND ITS SENSIBLE WX...CLOUDS OFFSHORE
EXCPT THOSE ASSOC WITH PASSAGE OF 500HPA SHORT WV SAT...WHICH
RESULTS IN CHC -SHRA SAT OVER W NEW ENG AND MORE CLOUDS SAT. ALL
GUID HAS FAIR AND WARMING CONDS SUN/MON AS 500HPA RIDGE DOMINATES.
SO WHILE ALL GUID IS IN AGREEMENT ITS NOT EXACTLY A HIGH
CONFIDENCE FCST AS A COUPLE HUNDRED MILE SHIFT COULD RESULT IN
DAMP...COOL AND DISMAL CONDS PARTICULARLY FM HUD VLY E. AND A
SHIFT FURTHER EAST COULD RESULT IN A DRY AND WARMER FCST. FOR
NOW WILL POP EFP WITH OVERNIGHT HPC GUID.
&&
.AVIATION /18Z TUESDAY THROUGH SUNDAY/...
VFR FLYING CONDITIONS WILL START THE TAF PERIOD BEFORE
DETERIORATING TO MVFR/IFR ASSOCIATED WITH SHOWERS/THUNDERSTORMS
THIS AFTERNOON AND EVENING...AND LOW STRATUS TONIGHT INTO
WEDNESDAY.
THIS AFTERNOON...VFR FLYING CONDITIONS WILL START THE TAF
PERIOD...WITH BROKEN MID AND HIGH CLOUDS ACROSS THE REGION.
LOW-LEVEL MOISTURE WILL CONTINUE TO INCREASE ACROSS THE REGION AS A
FRONTAL BOUNDARY APPROACHES THE REGION. THE COMBINATION OF THESE TWO
FEATURES WILL HELP TO FOCUS SCATTERED SHOWERS AND THUNDERSTORMS THIS
AFTERNOON...WITH THE GREATEST THREAT BETWEEN 21Z-00Z. HAVE INDICATED
A TEMPO GROUP DURING THIS TIME FOR THUNDERSTORMS AND VCSH THROUGH
THE REMAINDER OF THE AFTERNOON...DUE TO CONTINUED UNCERTAINTIES
REGARDING THE EXACT PLACEMENT OF CONVECTION. WINDS WILL BE OUT OF
THE SOUTH/SOUTHWEST BETWEEN 5-10 KNOTS.
TONIGHT INTO WEDNESDAY...THE THUNDERSTORM THREAT SHOULD DIMINISH BY
00Z WITH THE LOSS OF DAYTIME HEATING. THE FRONTAL BOUNDARY WILL
CONTINUE TO LINGER ACROSS THE REGION TONIGHT...PROVIDING THE FOCUS
FOR WIDELY SCATTERED DRIZZLE/LIGHT SHOWERS. HAVE CONTINUED TO
INDICATE VCSH IN THE TAFS THROUGH THE NIGHTTIME HOURS BUT COVERAGE
IS NOT EXPECTED TO BE WIDESPREAD. ENOUGH LOW-LEVEL MOISTURE WILL
ALSO BE IN PLACE TO PROMOTE MVFR LOW STRATUS FORMATION AT ALL TAF
SITES...WITH THE EXCEPTION OF IFR STRATUS AT KPSF. MVFR VISIBILITIES
SHOULD ALSO ACCOMPANY THE LOW STRATUS AT ALL TAF SITES EXCEPT KALB.
DEPENDING ON HOW MUCH RAIN FALLS THIS AFTERNOON/EVENING...THERE IS A
CHANCE FOR IFR FOG DEVELOPMENT TOWARDS DAYBREAK...AND WILL HAVE TO
MONITOR THIS THREAT WITH LATER TAF ISSUANCES.
MVFR STRATUS SHOULD LINGER AT THE TAF SITES INTO THE DAY WEDNESDAY
WITH PATCHY DRIZZLE/LIGHT SHOWERS CONTINUING.
WINDS WILL BE LIGHT AND VARIABLE TONIGHT AND WEDNESDAY OUT OF THE
NORTH/NORTHEAST GENERALLY LESS THAN 5 KNOTS.
OUTLOOK...
WEDNESDAY NIGHT AND THURSDAY: NO OPERATIONAL IMPACT. NO SIG WX.
THURSDAY NIGHT: MODERATE OPERATIONAL IMPACT. CHANCE OF SHRA.
FRIDAY: MODERATE OPERATIONAL IMPACT. CHANCE OF SHRA...TSRA.
FRIDAY NIGHT AND SATURDAY: LOW OPERATIONAL IMPACT. SLIGHT CHANCE OF
SHRA...TSRA.
SATURDAY NIGHT AND SUNDAY: NO OPERATIONAL IMPACT. NO SIG WX.
&&
.FIRE WEATHER...
A COLD FRONT WILL PUSH SOUTH THROUGH THE REGION TODAY AND TONIGHT...TRIGGERING
A ROUND OF SHOWERS AND THUNDERSTORMS. THIS WILL KEEP RH VALUES
HIGH WITH RH 45 TO 55 PERCENT THIS AFTERNOON...NEAR 100 PERCENT
TONIGHT 50 TO 60 PERCENT WEDNESDAY. LATE WEDNESDAY AND THURSDAY
HIGH PRESSURE WILL BUILD OVER THE NORTHEAST WITH SEASONABLE
TEMPERATURES.
&&
.HYDROLOGY...
SHOWERS AND THUNDERSTORMS ARE LIKELY THIS AFTERNOON WITH A QUARTER
TO HALF AN INCH QPF...AND LOCALLY HIGHER AMOUNTS CAPABLE OF
PONDING OF WATER ON ROADWAYS AND POORLY DRAINED LOW LYING AREAS.
SCATTERED SHOWERS WILL LINGER TUESDAY NIGHT INTO WEDNESDAY
MORNING BUT SHOULD BE LIGHT.
THERE IS ALSO A CHANCE OF MORE RAIN WITH SHOWERS AND THUNDERSTORMS
EXPECTED FRIDAY.
FOR DETAILS ON SPECIFIC AREA RIVERS AND LAKES...INCLUDING OBSERVED
AND FORECAST RIVER STAGES AND LAKE ELEVATIONS...PLEASE VISIT THE
ADVANCED HYDROLOGIC PREDICTION SERVICE /AHPS/ GRAPHS ON OUR WEBSITE.
&&
.ALY WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...NONE.
MA...NONE.
VT...NONE.
&&
$$
SYNOPSIS...SNYDER
NEAR TERM...FRUGIS/11/NAS
SHORT TERM...SNYDER
LONG TERM...SNYDER
AVIATION...IRL
FIRE WEATHER...SNYDER
HYDROLOGY...SNYDER
AREA FORECAST DISCUSSION
NWS ALBANY NY
1228 PM EDT TUE MAY 27 2014
.SYNOPSIS...
A COLD FRONT WILL PUSH SOUTH THROUGH THE REGION TODAY AND
TONIGHT...TRIGGERING A ROUND OF SHOWERS AND THUNDERSTORMS. LATE
WEDNESDAY AND THURSDAY HIGH PRESSURE WILL BUILD OVER THE NORTHEAST WITH
SEASONABLE TEMPERATURES. THURSDAY NIGHT AND FRIDAY ANOTHER COLD
FRONT AND A MID LEVEL WEATHER DISTURBANCE WILL PUSH THROUGH WITH
UNSETTLED WEATHER. HIGH PRESSURE WILL BUILD ALONG THE EASTERN
SEABOARD BY LATE IN THE WEEKEND.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 1230 PM EDT...A SERIES OF COLD FRONTS REMAIN SET UP CLOSE
TO THE REGION...WITH A BACKDOOR BOUNDARY STRETCHING FROM THE NORTH
COUNTRY OF NEW YORK TOWARDS CENTRAL NEW ENGLAND...AND ANOTHER
FRONTAL BOUNDARY EXTENDING SOUTHWEST ACROSS ONTARIO. THESE COLD
FRONTS WILL SLOWLY DRIFT SOUTHWARD TOWARDS OUR AREA
TODAY...SETTING OFF SOME AFTERNOON SHOWERS AND THUNDERSTORMS.
SHOWERS FROM EARLIER THIS MORNING HAVE WEAKENED AND MOVED EASTWARD
INTO NEW ENGLAND...LEAVING DRY WEATHER IN ITS WAKE. THERE HAVE
BEEN BREAKS IN THE CLOUDS...ALLOWING FOR TEMPS TO WARM QUICKLY WITH
DEWPOINTS GENERALLY IN THE 50S. AS TEMPS WARM INTO THE UPPER 70S
TO LOW 80S...CONVECTIVE CU CLOUDS WILL DEVELOP ACROSS THE
REGION...WITH SOME SHOWERS/THUNDERSTORMS DEVELOPING AS EARLY AS
NOON-2 PM. THE LATEST 3KM HRRR SHOWS MAINLY DISORGANIZED ACTIVITY
ACROSS OUR AREA...WITH THE MOST CONCENTRATION OF
SHOWERS/THUNDERSTORMS OVER THE ADIRONDACKS/SRN VT /CLOSER TO THE
BACKDOOR BOUNDARY/ AND ACROSS CENTRAL NY AND EVENTUALLY SPILLING
INTO THE CATSKILLS AND MID HUDSON VALLEY BY LATE THIS AFTN INTO
THIS EVENING...AS THE BEST MOISTURE/INSTABILITY AXIS WILL BE JUST
WEST OF OUR AREA.
SPC HAS OUR AREA IN /SEE TEXT/ FOR SEVERE WEATHER...AS AN
ISOLATED SEVERE STORM CANNOT BE RULED OUT. WITH FZL LEVEL/-20
DEGREE C HEIGHTS HIGHER THAN LAST WEEK...AND MID LEVEL LAPSE RATES
NOT OVERLY IMPRESSIVE...IT WILL BE TOUGH FOR MANY OF THE STORMS
TO BE ABLE TO PRODUCE LARGE HAIL. STILL...SMALL HAIL...HEAVY
DOWNPOURS...AND GUSTY WINDS MAY ACCOMPANY ANY STORM...AND THIS
WORDING WILL BE STRESSED IN THE GRIDS AND HWO STATEMENT.
HIGHS TODAY IN THE 80 TO 85 RANGE...BUT MID TO UPPER 70S HIGHER
TERRAIN. THE COLD FRONT SHOULD TRACK THROUGH TONIGHT BUT COLD
ADVECTION IS RATHER GRADUAL...SO LOWS IN THE 55 TO 60 DEGREE RANGE
BUT LOWER 50S HIGHER TERRAIN. COVERAGE OF SHOWERS SHOULD DECREASE
TO SCATTERED TO ISOLATED LATER AT NIGHT AND EARLY TOMORROW
MORNING...WITH THE THREAT FOR THUNDER DIMINISHING GREATLY AFTER
SUNSET THIS EVENING.
&&
.SHORT TERM /WEDNESDAY THROUGH FRIDAY NIGHT/...
THIS PERIOD WILL BE DOMINATED BY A FAST NW FLOW AT 500HPA...AS A
PARADE OF SHORT WVS PASSES THROUGH THE REGION...EACH SHARPENING A
500HPA TROF OVER NEW ENG...WHILE A SUBSTANTIAL 500HPA RIDGE BUILDS
IN THE UPR GRT PLAINS AND SHIFTS INTO THE GRTLKS. GENERALLY THE
MDL SUITE IS IN AGREEMENT DURING THIS PERIOD.
THE 1ST CDFNT IS ALONG I-80 WED MRNG....AND SAGGING S AS HIGH
PRESSURE BUILDS FM MARITIMES INTO NE USA IN INCRG E-SE MARINE
LAYER FLOW. AT SAME TIME ONE SHORT WV IS MVNG THRU FCA IN NW FLOW.
RESULT WILL BE CONSIDERABLE CLOUDS WED...DCRNG IN AFTN...AND THE
THREAT OF SCT -SHRA IN THE MRNG. TEMPS WILL COOL CONSIDERABLY FM
MON/TUES AS FCA IS IN MARITIME FLOW OFF GULF OF MAINE.
WED NT/THU 500HPA FLOW IS NW...WE TAKE A BREAK FM SHORT WV PARADE
AND SFC HIGH BUILDS INTO NEW ENG AND NY WITH GENERALLY FAIR...DRY
AND SLIGHTLY BLO NORMAL TEMPS. MINS WED NT WILL BE IN THE
40S...HIGHS THU IN THE UPPER 60S AND 70S.
THU NT A STRONG 500 HPA SHORT WV DIVES FM OTTAWA VLY INTO THE
NE...AS ITS CDFNT REACHES THE ST LAWRENCE VLY BY FRI MRNG. THESE
SYSTEMS TRANSIT FCA FRI AND FR NT WITH INCR THREAT OF -SHRA/SCT
TSTMS LATE THU N...AND ACROSS FCA FRI AND FRI NT WHEN 500HPA
TEMPS FALL TO -20C...AND A STRONG DIURNAL ASPECT AS ALMOST SUMMER
SOLSTICE SUN DURING THE DAY FRI. TEMPS WILL BE NR TO SLIGHTLY BLOW
NORMAL TO END THIS PERIOD.
&&
.LONG TERM /SATURDAY THROUGH MONDAY/...
WHILE THE MDL SUITE IS IN AGREEMENT WITH THE GENERAL PATTERN OF A
SHARP 500HPA TROF JUST OFF THE US EAST COAST...AND A SHARP OR
CLOSED 590 HPA HIGH OVER GRTLKS AND MIDWEST...WITH FCA BWTN THESE
SYSTEMS SAT...AND A GENERALLY SHIFT TO THE EAST TO END THE EFP.
THE QUESTION IS HOW MUCH CLOUDINESS...MARINE LAYER AIR AND
POSSIBLY A 500HPA CUTOFF WILL IMPACT THE FCA. THE ECMWF/HPC/GFS/GEM
TEND TO KEEP BULK OF THE TROF AND ITS SENSIBLE WX...CLOUDS OFFSHORE
EXCPT THOSE ASSOC WITH PASSAGE OF 500HPA SHORT WV SAT...WHICH
RESULTS IN CHC -SHRA SAT OVER W NEW ENG AND MORE CLOUDS SAT. ALL
GUID HAS FAIR AND WARMING CONDS SUN/MON AS 500HPA RIDGE DOMINATES.
SO WHILE ALL GUID IS IN AGREEMENT ITS NOT EXACTLY A HIGH
CONFIDENCE FCST AS A COUPLE HUNDRED MILE SHIFT COULD RESULT IN
DAMP...COOL AND DISMAL CONDS PARTICULARLY FM HUD VLY E. AND A
SHIFT FURTHER EAST COULD RESULT IN A DRY AND WARMER FCST. FOR
NOW WILL POP EFP WITH OVERNIGHT HPC GUID.
&&
.AVIATION /18Z TUESDAY THROUGH SUNDAY/...
JUST MID AND HIGH CLOUDS ACROSS THE REGION THIS MORNING. THERE ARE
SOME SCATTERED SHOWERS IN THE ADIRONDACKS THAT ARE TENDING TO DRY UP
AS THEY MOVE EAST...BUT ACKNOWLEDGING VCSH AT KALB...KGFL AND KPSF
AFTER ABOUT 14Z-15Z. STILL...CONDITIONS SHOULD BE VFR UNTIL THE MORE
WIDESPREAD SHOWERS AND THUNDERSTORMS DEVELOP LATER THIS AFTERNOON.
INDICATING MVFR VISIBILITIES IN PREDOMINANT SHOWERS AFTER 18Z-
21Z. IN ADDITION...WILL INCLUDE A PROB30 GROUP TO ACCOUNT FOR THE
POSSIBILITY OF SOME SCATTERED -TSRA AROUND THE REGION...BUT WILL
KEEP VSBYS/CIGS ABOVE IFR THRESHOLDS.
THE FRONT TRACKS TRACKS THROUGH THIS EVENING BUT COVERAGE OF SHOWERS
WILL BE SLOW TO DECREASE...SO KEEPING VCSH THROUGH THE NIGHT AFTER
00Z AS CEILINGS CONTINUE TO LOWER SOLIDLY INTO THE MVFR RANGE
THROUGH 04Z AND BEYOND...AND MAY APPROACH IFR LATE TONIGHT...BUT
AGAIN...SOME UNCERTAINTIES SO LATER FORECASTS MAY INDICATE SOME IFR.
WINDS SHOULD BE SOUTH TO SOUTHWEST AT NEAR 10 KT TODAY..SHIFTING TO
NORTH AND NORTHEAST AFTER THE FRONTAL PASSAGE LATE THIS AFTERNOON
AND EVENING. WINDS ARE EXPECTED TO DECREASE TO LESS THAN 6 KT
THROUGH TONIGHT.
OUTLOOK...
WEDNESDAY NIGHT AND THURSDAY: NO OPERATIONAL IMPACT. NO SIG WX.
THURSDAY NIGHT: MODERATE OPERATIONAL IMPACT. CHANCE OF SHRA.
FRIDAY: MODERATE OPERATIONAL IMPACT. CHANCE OF SHRA...TSRA.
FRIDAY NIGHT AND SATURDAY: LOW OPERATIONAL IMPACT. SLIGHT CHANCE OF
SHRA...TSRA.
SATURDAY NIGHT AND SUNDAY: NO OPERATIONAL IMPACT. NO SIG WX.
&&
.FIRE WEATHER...
A COLD FRONT WILL PUSH SOUTH THROUGH THE REGION TODAY AND TONIGHT...TRIGGERING
A ROUND OF SHOWERS AND THUNDERSTORMS. THIS WILL KEEP RH VALUES
HIGH WITH RH 45 TO 55 PERCENT THIS AFTERNOON...NEAR 100 PERCENT
TONIGHT 50 TO 60 PERCENT WEDNESDAY. LATE WEDNESDAY AND THURSDAY
HIGH PRESSURE WILL BUILD OVER THE NORTHEAST WITH SEASONABLE
TEMPERATURES.
&&
.HYDROLOGY...
SHOWERS AND THUNDERSTORMS ARE LIKELY THIS AFTERNOON WITH A QUARTER
TO HALF AN INCH QPF...AND LOCALLY HIGHER AMOUNTS CAPABLE OF
PONDING OF WATER ON ROADWAYS AND POORLY DRAINED LOW LYING AREAS.
SCATTERED SHOWERS WILL LINGER TUESDAY NIGHT INTO WEDNESDAY
MORNING BUT SHOULD BE LIGHT.
THERE IS ALSO A CHANCE OF MORE RAIN WITH SHOWERS AND THUNDERSTORMS
EXPECTED FRIDAY.
FOR DETAILS ON SPECIFIC AREA RIVERS AND LAKES...INCLUDING OBSERVED
AND FORECAST RIVER STAGES AND LAKE ELEVATIONS...PLEASE VISIT THE
ADVANCED HYDROLOGIC PREDICTION SERVICE /AHPS/ GRAPHS ON OUR WEBSITE.
&&
.ALY WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...NONE.
MA...NONE.
VT...NONE.
&&
$$
SYNOPSIS...SNYDER
NEAR TERM...FRUGIS/11/NAS
SHORT TERM...SNYDER
LONG TERM...SNYDER
AVIATION...FRUGIS/NAS
FIRE WEATHER...SNYDER
HYDROLOGY...SNYDER
AREA FORECAST DISCUSSION
NWS ALBANY NY
1031 AM EDT TUE MAY 27 2014
.SYNOPSIS...
A COLD FRONT WILL PUSH SOUTH THROUGH THE REGION TODAY AND
TONIGHT...TRIGGERING A ROUND OF SHOWERS AND THUNDERSTORMS. LATE
WEDNESDAY AND THURSDAY HIGH PRESSURE WILL BUILD OVER THE NORTHEAST WITH
SEASONABLE TEMPERATURES. THURSDAY NIGHT AND FRIDAY ANOTHER COLD
FRONT AND A MID LEVEL WEATHER DISTURBANCE WILL PUSH THROUGH WITH
UNSETTLED WEATHER. HIGH PRESSURE WILL BUILD ALONG THE EASTERN
SEABOARD BY LATE IN THE WEEKEND.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 1030 AM EDT...A SERIES OF COLD FRONTS IS SET UP CLOSE TO THE
REGION...WITH A BACKDOOR BOUNDARY STRETCHING FROM THE NORTH
COUNTRY OF NEW YORK TOWARDS CENTRAL NEW ENGLAND...AND ANOTHER
FRONTAL BOUNDARY EXTENDING SOUTHWEST ACROSS ONTARIO. THESE COLD
FRONTS WILL SLOWLY DRIFT SOUTHWARD TOWARDS OUR AREA TODAY...SETTING
OFF SOME AFTERNOON SHOWERS AND THUNDERSTORMS.
SHOWERS FROM EARLIER THIS MORNING HAVE WEAKENED AND MOVED EASTWARD
INTO NEW ENGLAND...LEAVING DRY WEATHER IN ITS WAKE. THERE HAVE
BEEN BREAKS IN THE CLOUDS...ALLOWING FOR TEMPS TO WARM QUICKLY WITH
DEWPOINTS GENERALLY IN THE 50S. AS TEMPS WARM INTO THE UPPER 70S
TO LOW 80S...CONVECTIVE CU CLOUDS WILL DEVELOP ACROSS THE
REGION...WITH SOME SHOWERS/THUNDERSTORMS DEVELOPING AS EARLY AS
NOON-2 PM. THE LATEST 3KM HRRR SHOWS MAINLY DISORGANIZED ACTIVITY
ACROSS OUR AREA...WITH THE MOST CONCENTRATION OF
SHOWERS/THUNDERSTORMS OVER THE ADIRONDACKS/SRN VT /CLOSER TO THE
BACKDOOR BOUNDARY/ AND ACROSS CENTRAL NY AND EVENTUALLY SPILLING
INTO THE CATSKILLS AND MID HUDSON VALLEY BY LATE THIS AFTN INTO
THIS EVENING...AS THE BEST MOISTURE/INSTABILITY AXIS WILL BE JUST
WEST OF OUR AREA.
SPC HAS OUR AREA IN /SEE TEXT/ FOR SEVERE WEATHER...AS AN
ISOLATED SEVERE STORM CANNOT BE RULED OUT. WITH FZL LEVEL/-20
DEGREE C HEIGHTS HIGHER THAN LAST WEEK...AND MID LEVEL LAPSE RATES
NOT OVERLY IMPRESSIVE...IT WILL TOUGH FOR MANY OF THE STORMS TO BE
ABLE TO PRODUCE LARGE HAIL. STILL...SMALL HAIL...HEAVY
DOWNPOURS...AND GUSTY WINDS MAY ACCOMPANY ANY STORM...AND THIS
WORDING WILL BE STRESSED IN THE GRIDS AND HWO STATEMENT.
HIGHS TODAY IN THE 80 TO 85 RANGE...BUT MID TO UPPER 70S HIGHER
TERRAIN. THE COLD FRONT SHOULD TRACK THROUGH TONIGHT BUT COLD
ADVECTION IS RATHER GRADUAL...SO LOWS IN THE 55 TO 60 DEGREE RANGE
BUT LOWER 50S HIGHER TERRAIN. COVERAGE OF SHOWERS SHOULD DECREASE
TO SCATTERED TO ISOLATED LATER AT NIGHT AND EARLY TOMORROW
MORNING...WITH THE THREAT FOR THUNDER DIMINISHING GREATLY AFTER
SUNSET THIS EVENING.
&&
.SHORT TERM /WEDNESDAY THROUGH FRIDAY NIGHT/...
THIS PERIOD WILL BE DOMINATED BY A FAST NW FLOW AT 500HPA...AS A
PARADE OF SHORT WVS PASSES THROUGH THE REGION...EACH SHARPENING A
500HPA TROF OVER NEW ENG...WHILE A SUBSTANTIAL 500HPA RIDGE BUILDS
IN THE UPR GRT PLAINS AND SHIFTS INTO THE GRTLKS. GENERALLY THE
MDL SUITE IS IN AGREEMENT DURING THIS PERIOD.
THE 1ST CDFNT IS ALONG I-80 WED MRNG....AND SAGGING S AS HIGH
PRESSURE BUILDS FM MARITIMES INTO NE USA IN INCRG E-SE MARINE
LAYER FLOW. AT SAME TIME ONE SHORT WV IS MVNG THRU FCA IN NW FLOW.
RESULT WILL BE CONSIDERABLE CLOUDS WED...DCRNG IN AFTN...AND THE
THREAT OF SCT -SHRA IN THE MRNG. TEMPS WILL COOL CONSIDERABLY FM
MON/TUES AS FCA IS IN MARITIME FLOW OFF GULF OF MAINE.
WED NT/THU 500HPA FLOW IS NW...WE TAKE A BREAK FM SHORT WV PARADE
AND SFC HIGH BUILDS INTO NEW ENG AND NY WITH GENERALLY FAIR...DRY
AND SLIGHTLY BLO NORMAL TEMPS. MINS WED NT WILL BE IN THE
40S...HIGHS THU IN THE UPPER 60S AND 70S.
THU NT A STRONG 500 HPA SHORT WV DIVES FM OTTAWA VLY INTO THE
NE...AS ITS CDFNT REACHES THE ST LAWRENCE VLY BY FRI MRNG. THESE
SYSTEMS TRANSIT FCA FRI AND FR NT WITH INCR THREAT OF -SHRA/SCT
TSTMS LATE THU N...AND ACROSS FCA FRI AND FRI NT WHEN 500HPA
TEMPS FALL TO -20C...AND A STRONG DIURNAL ASPECT AS ALMOST SUMMER
SOLSTICE SUN DURING THE DAY FRI. TEMPS WILL BE NR TO SLIGHTLY BLOW
NORMAL TO END THIS PERIOD.
&&
.LONG TERM /SATURDAY THROUGH MONDAY/...
WHILE THE MDL SUITE IS IN AGREEMENT WITH THE GENERAL PATTERN OF A
SHARP 500HPA TROF JUST OFF THE US EAST COAST...AND A SHARP OR
CLOSED 590 HPA HIGH OVER GRTLKS AND MIDWEST...WITH FCA BWTN THESE
SYSTEMS SAT...AND A GENERALLY SHIFT TO THE EAST TO END THE EFP.
THE QUESTION IS HOW MUCH CLOUDINESS...MARINE LAYER AIR AND
POSSIBLY A 500HPA CUTOFF WILL IMPACT THE FCA. THE ECMWF/HPC/GFS/GEM
TEND TO KEEP BULK OF THE TROF AND ITS SENSIBLE WX...CLOUDS OFFSHORE
EXCPT THOSE ASSOC WITH PASSAGE OF 500HPA SHORT WV SAT...WHICH
RESULTS IN CHC -SHRA SAT OVER W NEW ENG AND MORE CLOUDS SAT. ALL
GUID HAS FAIR AND WARMING CONDS SUN/MON AS 500HPA RIDGE DOMINATES.
SO WHILE ALL GUID IS IN AGREEMENT ITS NOT EXACTLY A HIGH
CONFIDENCE FCST AS A COUPLE HUNDRED MILE SHIFT COULD RESULT IN
DAMP...COOL AND DISMAL CONDS PARTICULARLY FM HUD VLY E. AND A
SHIFT FURTHER EAST COULD RESULT IN A DRY AND WARMER FCST. FOR
NOW WILL POP EFP WITH OVERNIGHT HPC GUID.
&&
.AVIATION /15Z TUESDAY THROUGH SATURDAY/...
JUST MID AND HIGH CLOUDS ACROSS THE REGION THIS MORNING. THERE ARE
SOME SCATTERED SHOWERS IN THE ADIRONDACKS THAT ARE TENDING TO DRY UP
AS THEY MOVE EAST...BUT ACKNOWLEDGING VCSH AT KALB...KGFL AND KPSF
AFTER ABOUT 14Z-15Z. STILL...CONDITIONS SHOULD BE VFR UNTIL THE MORE
WIDESPREAD SHOWERS AND THUNDERSTORMS DEVELOP LATER THIS AFTERNOON.
INDICATING MVFR VISIBILITIES IN PREDOMINANT SHOWERS AFTER 18Z-
21Z. IN ADDITION...WILL INCLUDE A PROB30 GROUP TO ACCOUNT FOR THE
POSSIBILITY OF SOME SCATTERED -TSRA AROUND THE REGION...BUT WILL
KEEP VSBYS/CIGS ABOVE IFR THRESHOLDS.
THE FRONT TRACKS TRACKS THROUGH THIS EVENING BUT COVERAGE OF SHOWERS
WILL BE SLOW TO DECREASE...SO KEEPING VCSH THROUGH THE NIGHT AFTER
00Z AS CEILINGS CONTINUE TO LOWER SOLIDLY INTO THE MVFR RANGE
THROUGH 04Z AND BEYOND...AND MAY APPROACH IFR LATE TONIGHT...BUT
AGAIN...SOME UNCERTAINTIES SO LATER FORECASTS MAY INDICATE SOME IFR.
WINDS SHOULD BE SOUTH TO SOUTHWEST AT NEAR 10 KT TODAY..SHIFTING TO
NORTH AND NORTHEAST AFTER THE FRONTAL PASSAGE LATE THIS AFTERNOON
AND EVENING. WINDS ARE EXPECTED TO DECREASE TO LESS THAN 6 KT
THROUGH TONIGHT.
OUTLOOK...
WEDNESDAY NIGHT AND THURSDAY: NO OPERATIONAL IMPACT. NO SIG WX.
THURSDAY NIGHT: MODERATE OPERATIONAL IMPACT. CHANCE OF SHRA.
FRIDAY: MODERATE OPERATIONAL IMPACT. CHANCE OF SHRA...TSRA.
FRIDAY NIGHT AND SATURDAY: LOW OPERATIONAL IMPACT. SLIGHT CHANCE OF
SHRA...TSRA.
SATURDAY NIGHT AND SUNDAY: NO OPERATIONAL IMPACT. NO SIG WX.
&&
.FIRE WEATHER...
A COLD FRONT WILL PUSH SOUTH THROUGH THE REGION TODAY AND TONIGHT...TRIGGERING
A ROUND OF SHOWERS AND THUNDERSTORMS. THIS WILL KEEP RH VALUES
HIGH WITH RH 45 TO 55 PERCENT THIS AFTERNOON...NEAR 100 PERCENT
TONIGHT 50 TO 60 PERCENT WEDNESDAY. LATE WEDNESDAY AND THURSDAY
HIGH PRESSURE WILL BUILD OVER THE NORTHEAST WITH SEASONABLE
TEMPERATURES.
&&
.HYDROLOGY...
SHOWERS AND THUNDERSTORMS ARE LIKELY THIS AFTERNOON WITH A QUARTER
TO HALF AN INCH QPF...AND LOCALLY HIGHER AMOUNTS CAPABLE OF
PONDING OF WATER ON ROADWAYS AND POORLY DRAINED LOW LYING AREAS.
SCATTERED SHOWERS WILL LINGER TUESDAY NIGHT INTO WEDNESDAY
MORNING BUT SHOULD BE LIGHT.
THERE IS ALSO A CHANCE OF MORE RAIN WITH SHOWERS AND THUNDERSTORMS
EXPECTED FRIDAY.
FOR DETAILS ON SPECIFIC AREA RIVERS AND LAKES...INCLUDING OBSERVED
AND FORECAST RIVER STAGES AND LAKE ELEVATIONS...PLEASE VISIT THE
ADVANCED HYDROLOGIC PREDICTION SERVICE /AHPS/ GRAPHS ON OUR WEBSITE.
&&
.ALY WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...NONE.
MA...NONE.
VT...NONE.
&&
$$
SYNOPSIS...SNYDER
NEAR TERM...FRUGIS/NAS
SHORT TERM...SNYDER
LONG TERM...SNYDER
AVIATION...FRUGIS/NAS
FIRE WEATHER...SNYDER
HYDROLOGY...SNYDER
AREA FORECAST DISCUSSION
NWS MOUNT HOLLY NJ
915 AM EDT TUE MAY 27 2014
.SYNOPSIS...
A BACKDOOR FRONT WILL PUSH DOWN FROM THE NORTHEAST TONIGHT. HIGH
PRESSURE WILL BUILD IN FOR WEDNESDAY THROUGH EARLY FRIDAY.A COLD
FRONT WILL MOVE THROUGH THE REGION ON FRIDAY WITH HIGH PRESSURE
BUILDING IN FOR THE WEEKEND. THE HIGH WILL BUILD ACROSS OUR AREA AND
THEN START TO SLIDE TO OUR SOUTH AND EAST ON MONDAY AND TUESDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
THE MORNING SHOULD CONTINUE TO FEATURE A FAIR AMOUNT OF CIRRUS
OVERHEAD. THE DEBRIS CLOUDS FROM THE CONVECTION OVER THE GREAT LAKES
REGION SHOULD VARY FROM TRANSPARENT TO OPAQUE.
INCREASING MOISTURE IN THE WEST TO SOUTHWEST SURFACE FLOW SHOULD
BRING DEW POINT READINGS INTO THE 60S THROUGHOUT OUR FORECAST AREA
BY AFTERNOON. EVEN WITH THE HIGH CLOUDS OVERHEAD, THE STRONG LATE
MAY SUNSHINE IS EXPECTED TO CAUSE TEMPERATURE TO SOAR INTO THE 80S
THROUGHOUT OUR REGION. THE LATEST GUIDANCE SUGGESTS THAT A FEW
LOCATIONS IN THE SOUTHERN PART OF OUR FORECAST AREA MAY REACH 90.
THE INCREASING MOISTURE IS ANTICIPATED TO RESULT IN THE DEVELOPMENT
OF SOME CUMULUS BY MIDDAY AND EVENTUALLY SCATTERED SHOWERS AND
THUNDERSTORMS DURING THE AFTERNOON HOURS. WE ARE EXPECTING THE MAIN
AREA OF CONVECTION TO SPREAD FROM NORTHWEST TO SOUTHEAST ACROSS OUR
REGION DURING THE MID TO LATE AFTERNOON HOURS IN RESPONSE TO
IMPULSES TRAVELING IN THE NORTHWESTERLY MID LEVEL FLOW.
THE THUNDERSTORMS MAY BE ACCOMPANIED BY HEAVY RAIN AS PRECIPITABLE
WATER VALUES ARE EXPECTED TO REACH THE 1.75 INCH NEIGHBORHOOD FOR
THIS AFTERNOON. SURFACE BASED CAPE VALUES SHOULD RISE INTO THE 1000
TO 1500 J/KG RANGE. FREQUENT LIGHTNING AND GUSTY WINDS ARE POSSIBLE
AS SOME OF THE STORMS MAY BECOME RATHER ROBUST.
NO SIG CHANGES TO THE NEAR TERM FCST, AS WE WAIT TO SEE HOW THE
SHWRS AND TSTMS DEVELOP. LATEST HRRR REALLY DESN`T GET MUCH GOING
UNTIL 17-18Z WITH A BIG INCREASE IN THE 22-23Z TIME FRAME.
IN THE REAL NEAR TERM, LOWERED POPS JUST A TAD.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 AM WEDNESDAY/...
THE CONVECTION IS EXPECTED TO LINGER INTO THIS EVENING. HOWEVER, AS
THE NIGHT PROGRESSES AND AS WE GRADUALLY LOSE THE EFFECTS OF DAYTIME
HEATING THE THUNDERSTORM ACTIVITY SHOULD DECREASE. WE ARE EXPECTING
A CLOUDY SKY FOR THE OVERNIGHT HOURS ALONG WITH SCATTERED RAIN
SHOWERS.
THE APPROACHING BACK DOOR COLD FRONT IS FORECAST TO BE INTO THE NEW
YORK CITY METROPOLITAN AREA AROUND 0600 UTC. THE BOUNDARY IS
EXPECTED TO EXTEND FROM AROUND THE POCONOS, ACROSS BUCKS COUNTY TO
LONG BEACH ISLAND AROUND 1200 UTC WEDNESDAY. CLOUDS ARE FORECAST TO
LOWER IN THE WAKE OF THE FRONT AND THE WIND SHOULD BECOME
NORTHEASTERLY.
&&
.LONG TERM /WEDNESDAY THROUGH MONDAY/...
WEDNESDAY STARTS OFF FEATURING THE BACKDOOR COLD FRONT SAGGING
SOUTHWARD THROUGH OUR REGION. THIS FRONT WILL COOL US DOWN AND
MAXIMUM TEMPERATURES ON WEDNESDAY WILL STRUGGLE TO REACH INTO THE
70S, ESPECIALLY TO THE NORTH AND WEST OF PHILADELPHIA. AREAS TO
THE SOUTH AND WEST MAY REACH INTO THE LOWER 70S BEFORE THE FRONT
PUSHES THROUGH.
SHOWERS WILL CONTINUE THROUGH WEDNESDAY BUT SHOULD START TO TAPER
OFF FROM NORTH TO SOUTH AS THE FRONT PUSHES SOUTH. THUNDERSTORMS
WILL BE POSSIBLE ACROSS THE SOUTHERN PARTS OF THE REGION BUT AS THE
FRONT MOVES THROUGH THE AREA, THE BEST CHANCES FOR THUNDER WILL PUSH
TO OUR SOUTH AS WELL.
HIGH PRESSURE WILL BUILD IN BEHIND THE COLD FRONT LATER ON WEDNESDAY
AND THIS SHOULD HELP TO BRING AN END TO THE PRECIPITATION. BY
LATE WEDNESDAY NIGHT INTO EARLY THURSDAY MORNING, THE SHOWERS
SHOULD END PRETTY MUCH EVERYWHERE WITH THE EXCEPTION OF OUR
SOUTHWESTERN ZONES IN THE DELMARVA.
THE HIGH WILL START TO TAKE HOLD AND CONTROL OUR WEATHER FOR
THURSDAY. A DRY BUT CLOUDY DAY IS IN STORE. TEMPERATURES DURING THE
DAY WILL REMAIN ON THE COOLER SIDE WITH MOST AREAS STRUGGLING TO
EVEN REACH 70 DEGREES.
FRIDAY WE WILL SEE ANOTHER COLD FRONT MOVE INTO AND THROUGH OUR
AREA. TEMPERATURES DURING THE DAY WILL REBOUND INTO THE 70S. THE
FRONT WILL CROSS THE REGION DURING THE AFTERNOON AND EVENING,
BRINGING SOME SHOWERS AND THUNDERSTORMS TO THE REGION. BETTER
CHANCES TO THE NORTH AND WEST. THIS FRONT DOESN`T LOOK TO HAVE ALL
THAT MUCH MOISTURE ASSOCIATED WITH IT SO WE CONTINUE TO MENTION
ONLY SLIGHT CHANCE TO CHANCE POPS.
SATURDAY AND SUNDAY SHOULD BE A BEAUTIFUL DAYS ACROSS THE REGION AS
HIGH PRESSURE BUILDS OVER OUR AREA. SKIES WILL BE SUNNY TO MOSTLY
SUNNY. TEMPERATURES WILL WARM INTO THE 70S ON BOTH DAYS ACROSS THE
FORECAST AREA.
MONDAY LOOKS TO START OFF AS A DRY DAY AS THE HIGH STARTS TO SLIDE
TO THE SOUTH AND EAST OF OUR AREA. TEMPERATURES WILL RISE INTO THE
UPPER 70S TO LOWER 80S. INCREASING CLOUDINESS THROUGH THE DAY AS
ANOTHER FRONTAL SYSTEM APPROACHES. THIS FRONT LOOKS TO MOVE
THROUGH THE REGION ON MONDAY NIGHT OR TUESDAY BUT STILL LOTS OF
UNCERTAINTY THIS FAR OUT.
&&
.AVIATION /13Z TUESDAY THROUGH SATURDAY/...
THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG, KILG,
KMIV, KACY AND SURROUNDING AREAS.
MAINLY VFR CONDITIONS ARE ANTICIPATED INTO THE EARLY AFTERNOON WITH
HIGH CLOUDS OVERHEAD AND A WEST TO SOUTHWEST WIND AROUND 5 TO 10
KNOTS. THE WIND MAY BEGIN TO GUST NEAR 16 OR 18 KNOTS DURING THE
EARLY AFTERNOON HOURS.
SHOWERS AND THUNDERSTORMS ARE FORECAST TO SPREAD INTO OUR REGION
FROM THE NORTHWEST DURING THE AFTERNOON HOURS. THE SHOWERS AND
THUNDERSTORMS ARE EXPECTED TO LINGER INTO THE EVENING. WHILE MUCH OF
THE TIME OUR TAF SITES SHOULD REMAIN IN THE VFR CATEGORY, THE
THUNDERSTORMS WILL BE CAPABLE OF LOWERING CEILING AND VISIBILITY
VALUES BRIEFLY TO MVFR OR IFR. ALSO, THE THUNDERSTORMS MAY BRING A
PERIOD OF HEAVY RAIN AND BRIEF WIND GUSTS FROM THE WEST OR NORTHWEST
IN EXCESS OF 30 KNOTS.
THE THREAT OF THUNDERSTORMS SHOULD DIMINISH DURING THE NIGHT.
HOWEVER, SCATTERED SHOWERS MAY LINGER WITH MAINLY VFR CONDITIONS.
A FEW SITES MAY BEGIN TO EXPERIENCE MVFR VISIBILITY RESTRICTIONS.
A COLD FRONT IS FORECAST TO BEGIN DROPPING INTO OUR REGION FROM THE
NORTHEAST LATE TONIGHT. CLOUDS ARE EXPECTED TO LOWER INTO THE MVFR
CATEGORY IN ITS WAKE AS THE WIND SHIFTS FROM THE WEST AND NORTHWEST
TO THE NORTHEAST AROUND 6 TO 12 KNOTS. THE BOUNDARY IS EXPECTED TO
REACH KABE AND KTTN AROUND 1000Z OR 1100Z WEDNESDAY.
OUTLOOK...
WEDNESDAY AND WEDNESDAY NIGHT...MVFR TO IFR CONDITIONS IN SHOWERS.
CHANCE FOR THUNDERSTORMS WILL DECREASE FROM NORTH TO SOUTH. EAST
TO NORTHEAST WINDS AROUND 10 TO 15 KNOTS, ESPECIALLY TOWARD KACY.
CONDITIONS WILL IMPROVE FROM NORTH TO SOUTH WITH A RETURN TO VFR
BY LATE WEDNESDAY NIGHT ACROSS THE TERMINALS.
THURSDAY...VFR CONDITIONS ARE EXPECTED. EAST TO NORTHEAST WINDS
AROUND 5 TO 10 KNOTS. GUSTIER ALONG THE COAST.
FRIDAY...VFR CONDITIONS EXPECTED. DETERIORATING CONDITIONS EXPECTED
AS A COLD FRONT MOVES TOWARDS AND THROUGH THE TERMINALS. SHOWERS AND
THUNDERSTORMS POSSIBLE.
SATURDAY...VFR CONDITIONS ARE EXPECTED.
&&
.MARINE...
THE WIND SHOULD BE MAINLY FROM THE SOUTH AND SOUTHWEST FOR TODAY
AROUND 10 TO 15 KNOTS. THE WIND IS FORECAST TO VEER TOWARD THE WEST
FOR TONIGHT AROUND 10 KNOTS. A COLD FRONT IS EXPECTED TO DROP INTO
OUR REGION FROM THE NORTHEAST LATE TONIGHT. THE WIND DIRECTION IS
ANTICIPATED TO SHIFT TO THE NORTHEAST ON OUR OCEAN WATERS NORTH OF
BARNEGAT INLET BY DAYBREAK ON WEDNESDAY AND SPEEDS SHOULD INCREASE
TO 10 TO 20 KNOTS BEHIND THE COLD FRONT.
WAVE HEIGHTS ON OUR OCEAN WATERS ARE FORECAST TO BE AROUND 2 OR 3
FEET FOR TODAY AND TONIGHT.
OUTLOOK...
A SMALL CRAFT ADVISORY IS IN EFFECT FOR THE OCEAN WATERS AND LOWER
DELAWARE FOR WEDNESDAY AND WEDNESDAY NIGHT.
WEDNESDAY THROUGH THURSDAY...WINDS START TO PICK UP IN THE EAST TO
NORTHEAST FLOW AND WILL START TO BECOME QUITE GUSTY BEHIND THE
FRONTAL PASSAGE. WINDS WILL GUST UP TO 30 KNOTS ON THE OCEAN THROUGH
WEDNESDAY NIGHT BEFORE STARTING TO SUBSIDE LATE. IN ADDITION, SEAS
WILL INCREASE TO 5 TO 6 FEET ON THE OCEAN BY WEDNESDAY
AFTERNOON/EARLY EVENING. SEAS ARE EXPECTED TO REMAIN ABOVE 5 FEET
THROUGH THURSDAY, FALLING BELOW SMALL CRAFT ADVISORY CRITERIA BY
THURSDAY EVENING. THE SMALL CRAFT ADVISORY WILL LIKELY NEED TO BE
EXTENDED THROUGH THURSDAY FOR HAZARDOUS SEAS.
THURSDAY NIGHT THROUGH SATURDAY...SEAS AND WINDS ARE EXPECTED TO
REMAIN BELOW SMALL CRAFT ADVISORY CRITERIA.
&&
.PHI WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NJ...NONE.
DE...NONE.
MD...NONE.
MARINE...SMALL CRAFT ADVISORY FROM 8 AM WEDNESDAY TO 6 AM EDT THURSDAY
FOR ANZ450>452.
SMALL CRAFT ADVISORY FROM NOON WEDNESDAY TO 6 AM EDT THURSDAY
FOR ANZ431-453>455.
&&
$$
SYNOPSIS...MEOLA
NEAR TERM...IOVINO/NIERENBERG
SHORT TERM...IOVINO
LONG TERM...MEOLA
AVIATION...IOVINO/MEOLA
MARINE...IOVINO/MEOLA
AREA FORECAST DISCUSSION
NWS MIAMI FL
144 PM EDT TUE MAY 27 2014
.AVIATION...
VFR CONDITIONS ARE EXPECTED TO PREVAIL WITH MOST SHRA/TSRA WELL
INLAND FROM THE TERMINALS. THERE COULD BE A TSRA LATE IN THE
AFTERNOON NEAR KAPF IF ANY CELL DRIFTS TO THE WEST BUT CONFIDENCE
IS TOO LOW AND LEFT VCSH IN THE TAF. THE SURFACE SOUTHEAST WIND
FLOW WILL BE DOMINANT ALONG THE EAST COAST BUT A FEW INLAND SITES
MAY BECOME L/V AFT 06-08Z.
KOB
&&
.PREV DISCUSSION... /ISSUED 1040 AM EDT TUE MAY 27 2014/
UPDATE...
SURFACE RIDGE AXIS NEAR FLORIDA/GEORGIA BORDER WILL SHIFT SOUTH TO
NORTH CENTRAL FLORIDA TODAY. LIGHT TO MODERATE EASTERLY FLOW WILL
CONTINUE ACROSS SOUTH FLORIDA. LOW/MID LEVEL LAPSE RATES ON THE
12Z SOUNDING THIS MORNING WERE ONLY AROUND 6 C/KM...WHICH IS NOT
THAT IMPRESSIVE. MOISTURE HAS INCREASED SINCE YESTERDAY...WITH
PWATS UP AROUND 1.3 INCHES. THERE WAS A SUBSIDENCE LAYER ALOFT
DUE TO UPPER LEVEL RIDGING. SO REMOVED THE MENTION OF HAIL FROM
THE HWO. THE WARM AND DRY AIR ALOFT MAY ALSO ONLY LEAD TO ONLY
ISOLATED THUNDERSTORM DEVELOPMENT THIS AFTERNOON. HOWEVER...SHOWERS
AND STORMS ARE EXPECTED TO DEVELOP ALONG THE SEA BREEZE BOUNDARIES
AS THE BOUNDARIES MOVE INLAND...MAINLY FROM NEAR LAKE OKEECHOBEE
AND WESTWARD. BUMPED UP POPS TO THE 30-40 PERCENT ACROSS PORTIONS
OF GLADES...HENDRY...AND COLLIER COUNTIES THIS AFTERNOON WHERE THE
SEA BREEZE BOUNDARIES ARE FORECAST TO COLLIDE. THIS IS ALSO
SUPPORTED BY THE HRRR AND LOCAL WRF RUNS. THE MAIN THREAT FROM
STORMS THIS AFTERNOON WILL BE GUSTY WINDS AND CLOUD TO GROUND
LIGHTNING.
PREV DISCUSSION... /ISSUED 719 AM EDT TUE MAY 27 2014/
AVIATION...
VFR WILL CONTINUE THROUGH THE FORECAST WITH SURFACE WIND L/V EARLY
AND SEA BREEZES DEVELOPING ALONG BOTH COASTS AROUND 16-18Z. THERE
COULD BE A FEW SHRA/TSRA DEVELOP ALONG THE WEST COAST SEA BREEZE
BUT WILL BE MOSTLY INLAND FROM THE KAPF TERMINAL.
KOB
PREV DISCUSSION... /ISSUED 418 AM EDT TUE MAY 27 2014/
DISCUSSION...
A SLIGHTLY MORE MOIST AND UNSETTLED PATTERN IS EXPECTED TO PREVAIL
ACROSS SOUTH FLORIDA THROUGH THE REMAINDER OF THE WEEK AND INTO THE
WEEKEND.
SURFACE HIGH PRESSURE WILL REMAIN ENTRENCHED ACROSS THE WESTERN
ATLANTIC THROUGH THE END OF THE WEEK PROVIDING AN EASTERLY FLOW
PATTERN. THIS COMBINED WITH DAILY SEA BREEZE INTERACTIONS ALONG WITH
DEEP LAYER MOISTURE SURGING IN FROM THE CARIBBEAN AND A GENERAL
WEAKENING OF THE UPPER RIDGE PATTERN WILL RESULT IN DAILY CHANCES
FOR SHOWERS AND THUNDERSTORMS THROUGH THE WEEK. DUE TO THE LACK OF
ORGANIZED DYNAMICS...ANY THUNDERSTORMS THAT DEVELOP EACH AFTERNOON
SHOULD REMAIN SUB-SEVERE. HOWEVER...AS WITH MOST CONVECTION THIS
TIME OF YEAR...GUSTY WINDS AND SMALL HAIL WILL BE A POSSIBILITY.
SLIGHTLY BETTER SHOWER AND THUNDERSTORM CHANCES WILL RESIDE ACROSS
THE INTERIOR AND WEST DUE TO THE WEAKER PENETRATION OF THE GULF
BREEZE AND PROXIMITY TO THE DEEPER MOISTURE AXIS.
EASTERLY FLOW LOOKS TO CONTINUE INTO THIS WEEKEND. AT THE SAME TIME
A STRONG H5 LOW WILL PUSH OFFSHORE THE NEW ENGLAND STATES. AS IT
DOES...IT IS EXPECTED TO SLIDE SLIGHTLY SOUTHWARD ALLOWING A WEAK
BACK DOOR COLD FRONT TO APPROACH SOUTH FLORIDA. THIS FEATURE SHOULD
BE RATHER DIFFUSE BY THE TIME IT REACHES THE LAKE OKEECHOBEE AREA
AND SHOULD HAVE NO REAL IMPACT ON THE WEATHER.
MODELS THEN DIVERGE QUITE DRAMATICALLY BY NEXT WEEK AS THE GFS
DEPICTS AN AREA OF LOW PRESSURE DEVELOPING ACROSS THE YUCATAN AND
PUSHING NORTH INTO THE GULF OF MEXICO. THE ECMWF ON THE OTHER HAND
KEEPS THE BULK OF THE MOISTURE WELL SOUTH WITH UPPER RIDGING
BUILDING INTO THE WESTERN GULF OF MEXICO.
AVIATION...
HIGH PRESSURE WILL CONTINUE TO SIT WELL TO THE NORTHEAST, KEEPING
AN EASTERLY FLOW ACROSS SOUTH FLORIDA. THE SEA AND GULF BREEZES
WILL KICK IN ONCE AGAIN EARLY THIS AFTERNOON. THIS WILL BRING
ANOTHER CHANCE OF CONVECTIVE DEVELOPMENT THIS AFTERNOON, MAINLY TO
THE WESTERN HALF OF THE AREA. OTHERWISE VFR CONDITIONS EXPECTED
THROUGH THE TAF PERIOD. THE ONE SITE THAT COULD BE THE EXCEPTION
IS KAPF, IF THERE ARE ANY IMPACTS FROM CONVECTIVE ACTIVITY.
MARINE...
TRANQUIL MARINE CONDITIONS WILL PERSIST THROUGH THE REMAINDER OF
THE WEEK WITH EAST WINDS OF 10-15 KNOTS AND SEAS AROUND 4 FEET OR
LESS. CHANCES FOR AFTERNOON AND EVENING SHOWERS AND THUNDERSTORMS
WILL BE POSSIBLE EACH DAY MAINLY OVER LAKE OKEECHOBEE AND THE
GULF WATERS.
&& LAUDERDALE 78 86 77 86 / 10 20 10 30 MIAMI 76 86 76 87 / 10
20 10 30 NAPLES 72 89 72 89 / 20 30 10 30
&&
.MFL WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
AM...NONE.
GM...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS MIAMI FL
1040 AM EDT TUE MAY 27 2014
.UPDATE...
SURFACE RIDGE AXIS NEAR FLORIDA/GEORGIA BORDER WILL SHIFT SOUTH TO
NORTH CENTRAL FLORIDA TODAY. LIGHT TO MODERATE EASTERLY FLOW WILL
CONTINUE ACROSS SOUTH FLORIDA. LOW/MID LEVEL LAPSE RATES ON THE
12Z SOUNDING THIS MORNING WERE ONLY AROUND 6 C/KM...WHICH IS NOT
THAT IMPRESSIVE. MOISTURE HAS INCREASED SINCE YESTERDAY...WITH
PWATS UP AROUND 1.3 INCHES. THERE WAS A SUBSIDENCE LAYER ALOFT
DUE TO UPPER LEVEL RIDGING. SO REMOVED THE MENTION OF HAIL FROM
THE HWO. THE WARM AND DRY AIR ALOFT MAY ALSO ONLY LEAD TO ONLY
ISOLATED THUNDERSTORM DEVELOPMENT THIS AFTERNOON. HOWEVER...SHOWERS
AND STORMS ARE EXPECTED TO DEVELOP ALONG THE SEA BREEZE BOUNDARIES
AS THE BOUNDARIES MOVE INLAND...MAINLY FROM NEAR LAKE OKEECHOBEE
AND WESTWARD. BUMPED UP POPS TO THE 30-40 PERCENT ACROSS PORTIONS
OF GLADES...HENDRY...AND COLLIER COUNTIES THIS AFTERNOON WHERE THE
SEA BREEZE BOUNDARIES ARE FORECAST TO COLLIDE. THIS IS ALSO
SUPPORTED BY THE HRRR AND LOCAL WRF RUNS. THE MAIN THREAT FROM
STORMS THIS AFTERNOON WILL BE GUSTY WINDS AND CLOUD TO GROUND
LIGHTNING.
&&
.PREV DISCUSSION... /ISSUED 719 AM EDT TUE MAY 27 2014/
AVIATION...
VFR WILL CONTINUE THROUGH THE FORECAST WITH SURFACE WIND L/V EARLY
AND SEA BREEZES DEVELOPING ALONG BOTH COASTS AROUND 16-18Z. THERE
COULD BE A FEW SHRA/TSRA DEVELOP ALONG THE WEST COAST SEA BREEZE
BUT WILL BE MOSTLY INLAND FROM THE KAPF TERMINAL.
KOB
PREV DISCUSSION... /ISSUED 418 AM EDT TUE MAY 27 2014/
DISCUSSION...
A SLIGHTLY MORE MOIST AND UNSETTLED PATTERN IS EXPECTED TO PREVAIL
ACROSS SOUTH FLORIDA THROUGH THE REMAINDER OF THE WEEK AND INTO THE
WEEKEND.
SURFACE HIGH PRESSURE WILL REMAIN ENTRENCHED ACROSS THE WESTERN
ATLANTIC THROUGH THE END OF THE WEEK PROVIDING AN EASTERLY FLOW
PATTERN. THIS COMBINED WITH DAILY SEA BREEZE INTERACTIONS ALONG WITH
DEEP LAYER MOISTURE SURGING IN FROM THE CARIBBEAN AND A GENERAL
WEAKENING OF THE UPPER RIDGE PATTERN WILL RESULT IN DAILY CHANCES
FOR SHOWERS AND THUNDERSTORMS THROUGH THE WEEK. DUE TO THE LACK OF
ORGANIZED DYNAMICS...ANY THUNDERSTORMS THAT DEVELOP EACH AFTERNOON
SHOULD REMAIN SUB-SEVERE. HOWEVER...AS WITH MOST CONVECTION THIS
TIME OF YEAR...GUSTY WINDS AND SMALL HAIL WILL BE A POSSIBILITY.
SLIGHTLY BETTER SHOWER AND THUNDERSTORM CHANCES WILL RESIDE ACROSS
THE INTERIOR AND WEST DUE TO THE WEAKER PENETRATION OF THE GULF
BREEZE AND PROXIMITY TO THE DEEPER MOISTURE AXIS.
EASTERLY FLOW LOOKS TO CONTINUE INTO THIS WEEKEND. AT THE SAME TIME
A STRONG H5 LOW WILL PUSH OFFSHORE THE NEW ENGLAND STATES. AS IT
DOES...IT IS EXPECTED TO SLIDE SLIGHTLY SOUTHWARD ALLOWING A WEAK
BACK DOOR COLD FRONT TO APPROACH SOUTH FLORIDA. THIS FEATURE SHOULD
BE RATHER DIFFUSE BY THE TIME IT REACHES THE LAKE OKEECHOBEE AREA
AND SHOULD HAVE NO REAL IMPACT ON THE WEATHER.
MODELS THEN DIVERGE QUITE DRAMATICALLY BY NEXT WEEK AS THE GFS
DEPICTS AN AREA OF LOW PRESSURE DEVELOPING ACROSS THE YUCATAN AND
PUSHING NORTH INTO THE GULF OF MEXICO. THE ECMWF ON THE OTHER HAND
KEEPS THE BULK OF THE MOISTURE WELL SOUTH WITH UPPER RIDGING
BUILDING INTO THE WESTERN GULF OF MEXICO.
AVIATION...
HIGH PRESSURE WILL CONTINUE TO SIT WELL TO THE NORTHEAST, KEEPING
AN EASTERLY FLOW ACROSS SOUTH FLORIDA. THE SEA AND GULF BREEZES
WILL KICK IN ONCE AGAIN EARLY THIS AFTERNOON. THIS WILL BRING
ANOTHER CHANCE OF CONVECTIVE DEVELOPMENT THIS AFTERNOON, MAINLY TO
THE WESTERN HALF OF THE AREA. OTHERWISE VFR CONDITIONS EXPECTED
THROUGH THE TAF PERIOD. THE ONE SITE THAT COULD BE THE EXCEPTION
IS KAPF, IF THERE ARE ANY IMPACTS FROM CONVECTIVE ACTIVITY.
MARINE...
TRANQUIL MARINE CONDITIONS WILL PERSIST THROUGH THE REMAINDER OF
THE WEEK WITH EAST WINDS OF 10-15 KNOTS AND SEAS AROUND 4 FEET OR
LESS. CHANCES FOR AFTERNOON AND EVENING SHOWERS AND THUNDERSTORMS
WILL BE POSSIBLE EACH DAY MAINLY OVER LAKE OKEECHOBEE AND THE
GULF WATERS.
&&
.PRELIMINARY POINT TEMPS/POPS...
WEST PALM BEACH 87 76 85 76 / 10 10 10 10
FORT LAUDERDALE 85 78 86 77 / 10 10 20 10
MIAMI 87 76 86 76 / 10 10 20 10
NAPLES 91 72 89 72 / 20 20 30 10
&&
.MFL WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
AM...NONE.
GM...NONE.
&&
$$
DISCUSSION...84/AK
AREA FORECAST DISCUSSION
NWS MELBOURNE FL
958 AM EDT TUE MAY 27 2014
.DISCUSSION...RIDGE AXIS OF SFC HIGH PRESSURE OVER THE WEST
ATLANTIC SHIFTS FARTHER SOUTH OVER THE AREA TODAY WHILE CENTER
SHIFTS FARTHER EASTWARD. THIS WILL LEAD TO A WEAKER ONSHORE FLOW
TODAY AND THEREFORE THE EAST COAST SEA BREEZE IS EXPECTED TO HAVE
A SLIGHTLY SLOWER INLAND MOVEMENT THROUGH THE AFTERNOON. ISOLATED
SHOWERS AND STORMS EXPECTED TO FORM SOON AFTER NOON ALONG AND
AHEAD OF SEA BREEZE...MAINLY WEST OF I-95 WHICH IS SUPPORTED BY
LOCAL WRF AND HRRR MODEL OUTPUT. INCREASING COVERAGE EXPECTED WEST
OF I-4 LATER IN THE AFTERNOON WHERE SEA BREEZE BOUNDARY
INTERACTIONS ARE MORE LIKELY. DRIER AIR ALOFT MAY STILL LEAD TO
ISOLATED STRONG STORMS OVER THE FAR INTERIOR TODAY WITH MAIN
THREAT BEING WIND GUSTS UP TO 40-50 MPH. SMALL HAIL LOOKS LESS
LIKELY TODAY WITH SLIGHTLY WARMER TEMPS ALOFT BUT STILL NOT OUT OF
THE QUESTION. ALSO...VERY WEAK STEERING FLOW WILL ONCE AGAIN LEAD
TO SLOW AND VARIABLE STORM MOTION AND LOCALLY HEAVY RAINFALL IN A
FEW SPOTS. HIGHS WILL BE NEAR NORMAL WITH VALUES RANGING FROM THE
MID- UPPER 80S ALONG THE COAST TO LOW 90S INLAND.
&&
.AVIATION...ISO SHRA/TSRA WILL INTI ALLY DEVELOP ALONG AND AHEAD
OF THE EAST COAST SEA BREEZE IN THE EARLY AFTERNOON WITH AN
INCREASE IN COVERAGE TOWARD LAKE COUNTY LATER IN THE DAY. THIS
ACTIVITY WILL PRODUCE TEMPO IFR/MVFR CONDS THROUGH THE AFTERNOON
HOURS MAINLY WEST OF I-95. WILL CONTINUE VCTS IN THE TAFS FOR
INTERIOR SITES FOR NOW.
&&
.MARINE...(PREVIOUS DISCUSSION) FAVORABLE CONDS FOR SMALL CRAFT
WITH A SWELL COMPONENT NR 11-12SEC AT COASTAL SITES ADDING ABOUT 1
TO 2 FT TO SIG WAVE HGHTS. RIDGE SINKING S CLOSER TO THE AREA
SHOULD REDUCE WINDS OVER THE OPEN AND OUTER WATERS WITH ECSB WINDS
IN THE 10 TO 15 KT RANGE AT EARLY TO MID AFTN ALONG THE IMMEDIATE
COAST.
&&
.MLB WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
AM...NONE.
&&
$$
WEITLICH/SPRATT
AREA FORECAST DISCUSSION
NWS PEACHTREE CITY GA
729 PM EDT WED MAY 28 2014
.UPDATE...
OUTFLOW DRIVEN CONVECTION WILL CONTINUE ACROSS MUCH OF THE CWFA
FOR THE NEXT FEW HOURS. HAVE UPDATED THE POPS ACCORDING TO THE
LATEST RADAR TRENDS. ALSO...THE HRRR DOES KEEP SOME ISOLATED
ACTIVITY IN AFTER 06Z...SO HAVE DONE THE SAME.
&&
.PREV DISCUSSION... /ISSUED 341 PM EDT WED MAY 28 2014/
SHORT TERM /TONIGHT THROUGH THURSDAY NIGHT/...
NO SIGNIFICANT CHANGES TO THE GENERAL TRENDS THROUGH THE SHORT TERM
FORECAST PERIOD. STRANDED UPPER LOW OVER THE LOWER MISSISSIPPI
VALLEY GETS NO KICKER TO MOVE AS MEDIUM RANGE MODELS SHOW IT DOES
NOT CONNECT WITH THE EAST COAST UPPER TROUGH BEFORE THE BUILDING
UPPER RIDGE ISOLATES IT ONCE AGAIN. ISOLATED TO SCATTERED DIURNAL
CONVECTION PATTERN WILL CONTINUE THROUGH THURSDAY NIGHT. INDICATIONS
ARE THAT MID-LEVEL LAPSE RATES SLOWLY DECREASE THROUGH THE PERIOD SO
CHANCES FOR STRONG TO SEVERE THUNDERSTORMS...ALTHOUGH NOT ZERO...
REMAIN SMALL AND SHOULD ACTUALLY DIMINISH SOME AGAIN THURSDAY.
OVERNIGHT LOWS ARE EXPECTED TO REMAIN MILD AND NEAR SEASONAL NORMALS
WITH AFTERNOON HIGHS AT OR SLIGHTLY ABOVE AVERAGE.
20
LONG TERM /FRIDAY THROUGH WEDNESDAY/...
LONG TERM FORECAST STILL LOOKS VERY SIMILAR WITH PULSE
THUNDERSTORM CONVECTION EACH DAY THROUGH SATURDAY BUT LOSING SOME
INSTABILITY FOR SUNDAY INTO MONDAY AS A WEDGE HELPS TO STABILIZE
THE AREA. CURRENT LONG TERM FORECAST IS ON TRACK SO VERY LITTLE IN
TERMS OF CHANGES. THE PREVIOUS DISCUSSION FOLLOWS.
11
/ISSUED AT 358 AM EDT WED MAY 28 2014/
MODELS ARE IN GOOD CONSENSUS THROUGH MUCH OF THE LONG TERM. WEAK
UPPER LOW WITH A BROAD AND DEEP MOISTURE FIELD LINGERS ACROSS THE
SOUTHEAST CONUS INTO THE WEEKEND ALLOWING FOR DECENT CHANCE POPS FOR
SHOWERS AND THUNDERSTORMS IN THE AFTERNOON AND EVENING PERIODS THEN
SOME CONTINUED WEAKER ACTIVITY POSSIBLE OVERNIGHT. LITTLE TO NO
SHEAR WITH MODERATE INSTABILITY WILL KEEP CONVECTIVE MODE OF THE
PULSE VARIETY WITH EVOLUTION LARGELY OUTFLOW DRIVEN OR RIDING ALONG
WAVES OF GULF MOISTURE FROM THE SOUTHWEST. SOME STRONG AND FEW
SEVERE STORMS STILL LOOK LIKE A GOOD BET AS HAS BEEN THE RECENT
TREND.
UPPER RIDGING BEGINS TO TAKE OVER SATURDAY INTO SUNDAY AND A SFC
HIGH SLIDING SOUTH ALONG THE EAST COAST LOOKS TO RESULT IN HYBRID
CAD. THE WEDGE FRONT LATER SATURDAY MAY PROVIDE SOME ENHANCED
FORCING AND FOCUS FOR CONVECTION. WHILE THE CAD LOOKS TO BE
SHORT-LIVED AS THE PARENT HIGH SLIDES EVENT FARTHER SOUTH...THE
RIDGING SHOULD STILL SERVE TO STABILIZE MUCH OF THE AREA FROM THE
EAST AND LESSEN SHOWER/STORM POTENTIAL SUNDAY THROUGH MONDAY. BETTER
STORM CHANCE STARTS TO RETURN TO THE AREA BY TUESDAY AS THE RIDGE
BREAKS DOWN.
FOR TEMPS...MADE SLIGHT ADJUSTMENTS FROM A GENERAL BLEND OF GUIDANCE
AND VALUES GENERALLY 5 DEGREES ABOVE NORMAL LOOK REASONABLE.
SLIGHTLY COOLER TEMPS ON TAP SUNDAY AND MONDAY FROM BRIEF WEDGE.
BAKER
&&
.AVIATION...
00Z UPDATE...
OUTFLOW DRIVEN CONVECTION WEAKENING NEAR ATL THIS EVENING.
EXPECT THIS TREND TO CONTINUE FOR THE NEXT TWO OR THREE HOURS.
ALSO...SOME PATCHY MVFR IS POSSIBLE WHERE IT RAINS. WILL HAVE TO
MONITOR AND MAY HAVE TO ADD TO THE ATL TAF IN LATER AMENDMENTS.
SCT AFTERNOON THUNDERSTORMS POSSIBLE AGAIN ON THURSDAY.
//ATL CONFIDENCE...00Z UPDATE...
MEDIUM CONFIDENCE ON EVE CONVECTION. HIGH CONFIDENCE REMAINING
ELEMENTS.
&&
.PRELIMINARY POINT TEMPS/POPS...
ATHENS 65 88 64 88 / 40 40 40 40
ATLANTA 67 85 67 86 / 50 40 30 40
BLAIRSVILLE 59 83 61 82 / 40 40 40 40
CARTERSVILLE 63 86 63 87 / 50 40 30 40
COLUMBUS 68 88 67 88 / 40 40 30 40
GAINESVILLE 66 86 66 86 / 40 40 40 40
MACON 65 88 65 88 / 70 40 30 40
ROME 64 86 63 87 / 50 40 30 40
PEACHTREE CITY 64 86 63 87 / 50 40 30 40
VIDALIA 69 90 69 90 / 70 40 30 40
&&
.FFC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
1242 PM CDT TUE MAY 27 2014
.DISCUSSION...
334 AM CDT
FORECAST CONCERNS CONTINUE TO FOCUS ON PRECIP/CONVECTION TRENDS
TODAY INTO TONIGHT...AS WEAK COLD FRONT SAGS SOUTH INTO THE AREA.
SHARP COOLING AND FOG LIKELY ALONG THE LAKE AS WINDS SHIFT NORTHEAST
LATER TODAY. FRONT CONTINUES TO PUSH VERY SLOWLY SOUTH OF THE
FORECAST AREA WEDNESDAY-THURSDAY WITH SCATTERED MAINLY DIURNAL
SHOWERS/STORMS LINGERING ACROSS CENTRAL IL/IN THROUGH MID-WEEK.
TEMPS COOL A BIT BEHIND THE FRONT...THOUGH MAINLY COOLER NEAR LAKE
MICHIGAN AS WINDS TURN NORTHEAST. TEMPS AWAY FROM THE LAKE NEAR
NORMAL...WITH A WARMING TREND INTO THE WEEKEND.
EARLY MORNING SURFACE MAP DEPICTS A WEAK AREA OF LOW PRESSURE OVER
THE UPPER MISSISSIPPI VALLEY...WITH A NEARLY STATIONARY COLD FRONTAL
BOUNDARY EXTENDING ACROSS NORTH CENTRAL WI TO NEAR THE SOO. ALOFT...
CLOSED UPPER LOW WELL TO OUR SOUTH CONTINUES TO DRIFT ALONG THE
TEXAS/OKLAHOMA BORDER...WHILE A SLOW MOVING MID-LEVEL TROUGH WAS
NOTED OVER MN/IA ALONG THE SOUTHERN PERIPHERY OF FASTER FLOW ALONG
THE CANADIAN BORDER. LITTLE IN THE WAY OF SIGNIFICANT FORCING NOTED
WITH JUST A COUPLE OF WEAK VORT MAXIMA MOVING THROUGH MODEST FLOW
ALOFT. EXPECTATION IS THAT DIURNAL INSTABILITY AND APPROACH OF THE
COLD FRONT FROM THE NORTH THIS AFTERNOON WILL BE THE BEST FOCUS FOR
RENEWED SHOWER AND THUNDERSTORM DEVELOPMENT. RECENT RUNS OF THE HRRR
CONCUR...AND HAVE MAINTAINED ONLY SOME SLIGHT CHANCE POPS FOR
ISOLATED SHRA/TSRA THIS MORNING. THUNDERSTORM COVERAGE THEN EXPECTED
TO INCREASE ALONG/SOUTH OF THE APPROACHING FRONT ACROSS SOUTHERN WI
AND NORTHERN IL DURING THE AFTERNOON. MODELS HAVE CONTINUED TO SHOW
SOME DIFFERENCES IN THE DETAILS OF THE SPEED OF THE WEAK FRONT...
WITH A PREFERENCE FOR SLIGHTLY FASTER GFS/LOCAL WRF SOLUTIONS WHICH
SLIDE FRONT DOWN THE ILLINOIS LAKE SHORE DURING THE LATE AFTERNOON
HOURS. WINDS SHIFTING NORTHEAST BEHIND THE FRONT ARE EXPECTED TO
BRING QUICK COOLING (NEAR 80 DROPPING INTO 60S) TO THE NORTH SHORE
AND ADJACENT AREAS BEFORE EVENING...ALONG WITH SOME FOG DUE TO COOL
LAKE AND HUMID AIR MASS. FORECAST SOUNDINGS INDICATE MLCAPES AROUND
500 J/KG WITH WEAK FLOW ALOFT CONTRIBUTING TO WEAK DEEP LAYER SHEAR.
THUS NOT EXPECTING SEVERE STORMS...THOUGH PRECIPITABLE WATER VALUES
ABOVE 1.50" PER 00Z DVN SOUNDING INDICATE HEAVY DOWNPOURS POSSIBLE.
STORMS SHOULD DECREASE IN COVERAGE WITH SUNSET...AS DIURNAL
INSTABILITY DECREASES.
FRONT CONTINUES TO PUSH SLOWLY SOUTH ACROSS THE FORECAST AREA
WEDNESDAY...MOVING JUST SOUTH OF THE CWA BY WEDNESDAY NIGHT. WITH A
WEAK MID-LEVEL TROUGH OVERHEAD THE FRONTAL BOUNDARY IS EXPECTED TO
AGAIN BE A FOCUS FOR SCATTERED DIURNAL CONVECTION...MAINLY SOUTH OF
I-80 CORRIDOR. PRECIP THREAT SHOULD DIMINISH SIGNIFICANTLY FARTHER
NORTH...AS COOLER MORE STABLE AIR SPREADS IN FROM THE NORTHEAST.
AFTER MAX TEMPS IN THE LOW-MID 80S TODAY...READINGS EXPECTED TO
RANGE FROM THE MID 60S ALONG THE LAKE TO THE MID-UPPER 70S
WEDNESDAY...WITH LOW 80S SOUTH CLOSER TO THE FRONT. UPPER RIDGE THEN
DEVELOPS AND BUILDS OVER THE REGION THURSDAY-FRIDAY DOWNSTREAM OF
HIGHLY AMPLIFIED WEST COAST TROUGH. SURFACE HIGH PRESSURE RIDGE OVER
THE NORTHERN/WESTERN LAKES WILL KEEP LAKE COOLING IN PLAY THROUGH
FRIDAY WHILE TEMPS OTHERWISE MODERATE BACK INTO THE 80S FARTHER
INLAND BENEATH BUILDING UPPER RIDGE. EFFECT OF LAKE COOLING WILL
DIMINISH INTO THE WEEKEND AS SURFACE WINDS GRADUALLY BECOME MORE
SOUTHEAST THAN NORTHEAST.
THE NEXT CHANCE OF SHOWERS AND THUNDERSTORMS WILL ARRIVE SUNDAY INTO
MONDAY AS JET STREAK AND SHORT WAVE PROPAGATE ACROSS THE UPPER
MIDWEST AND FLATTEN UPPER RIDGE. ECMWF REMAINS DEEPER THAN GFS AND
GEFS MEMBERS WITH THE SHORT WAVE...AND IN BRINGING COLD FRONT ACROSS
THE AREA SUNDAY NIGHT. GFS KEEPS FRONT TO OUR NORTH THROUGH
MONDAY...WITH SUPPORT OF GEFS ENSEMBLES WHICH MAINTAIN CONSISTENCY
AND SHOW FAIRLY MINIMAL SPREAD. THUS CONFIDENCE FAIRLY LOW IN
PICKING EITHER EXTREME IN VARIOUS SOLUTIONS AT THIS DISTANCE...AND
FORECAST FOR SUNDAY/MONDAY REPRESENT A BLEND TOWARD THE GEFS.
RATZER
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 18Z...
* SCATTERED THUNDERSTORMS THIS AFTERNOON/EVENING.
* SW WINDS SHIFTING TO THE NE BY LATE AFTERNOON/EARLY THIS
EVENING.
* LOW MVFR TO IFR CIGS DEVELOPING LATER THIS EVENING/OVERNIGHT.
KJB
//DISCUSSION...UPDATED 18Z...
THE MAIN WEATHER CONCERNS THIS AFTERNOON AND EARLY EVENING IS THE
TIMING OF THE WIND SHIFT OUT OF THE NORTH-NORTHEAST AS WELL AS THE
TIMING OF CONVECTIVE ACTIVITY OVER THE TERMINALS.
A COLD FRONTAL BOUNDARY IS CURRENTLY DROPPING SOUTH DOWN LAKE
MICHIGAN AND SOUTHERN PORTIONS OF WISCONSIN EARLY THIS AFTERNOON.
THIS FRONT IS INTERACTING WITH A WARM...MOIST AND UNSTABLE
ENVIRONMENT...LEADING TO SCATTERED SHOWERS AND STORMS IN ITS VICINITY
ACROSS SOUTHERN WISCONSIN AT THIS TIME. GIVEN THAT THIS BOUNDARY
WILL LIKELY BE THE MAIN FOCUS FOR CONVECTIVE ACTIVITY...AS IT
CONTINUES TO SAG SOUTHWARD LATER THIS AFTERNOON AND EVENING...SO TO
WILL THE THUNDERSTORMS. THEREFORE...IT STILL APPEARS THE MAIN THREAT
OF THUNDERSTORMS OVER AND NEAR THE EASTERN TERMINALS WILL BE AFTER
21 UTC TIMEFRAME...THROUGH ABOUT 00-01 UTC THIS EVENING. GIVEN THE
ABUNDANCE OF MOISTURE IN THE ATMOSPHERE...THESE THUNDERSTORMS WILL
BE CAPABLE OF PRODUCING A PERIOD OR TWO OF HEAVY
RAINFALL...POTENTIALLY LEADING TO SOME LOW VIS UNDER 2SM FOR A BRIEF
PERIOD.
IN ADDITION TO THE THUNDERSTORMS EXPECTED IN ASSOCIATION WITH THE
COLD FRONT...THERE MAY BE SOME ADDITIONAL ISOLATED TO WIDELY
SCATTERED THUNDERSTORMS DEVELOPING ACROSS PORTIONS OF NORTHERN
ILLINOIS AND PORTIONS OF NORTHWESTERN INDIANA EARLY THIS AFTERNOON.
THE LATEST AMDAR SOUNDING OUT OF KMDW INDICATES LITTLE TO NO CAP IN
PLACE TO PREVENT CONVECTIVE DEVELOPMENT. THEREFORE...ANY SUBTLE
SURFACE BOUNDARIES OR ASCENT COULD SPARK OFF A FEW ISOLATED SHOWERS
OR THUNDERSTORMS EARLIER THAN THE CURRENT TIMING ADVERTISED IN THE
TAFS. IT APPEARS THE AREAL COVERAGE OF THIS ACTIVITY WILL BE TOO
LOW TO INCLUDE IN THE TAF AT THIS TIME.
WINDS WILL QUICKLY SHIFT OUT OF THE NORTH-NORTHEAST IN THE WAKE OF
THIS FRONTAL BOUNDARY. THE CURRENT TIMING OF 00 UTC FOR ORD COULD
BE A BIT LATE...WITH THE POTENTIAL OF A PASSAGE AS EARLY AS THE 22
TO 23 UTC HOUR. HOWEVER...RATHER THAN SWITCHING TIMES NOW...WITH
LOWER CONFIDENCE...I WOULD LIKE TO WATCH THE TRENDS OVER THE NEXT
FEW HOURS BEFORE MAKING A CHANGE TO THIS TIMING.
LOW CLOUDS AND POSSIBLY EVEN SOME FOG ARE PROBABLE LATER THIS EVENING
AND OVERNIGHT. IT APPEARS THAT LOW END MVFR TO EVEN IFR CIGS COULD
DEVELOP ACROSS THE AREA FOR A PERIOD TONIGHT BEFORE IMPROVING BY
EARLY WEDNESDAY MORNING.
KJB
//ORD AND MDW CONFIDENCE...UPDATED 18Z...
* HIGH WITH SOME WIDELY SCATTERED THUNDERSTORMS LATER TODAY.
* MEDIUM IN TIMING AND ACTUAL IMPACTS AT TERMINALS.
* LOW MEDIUM IN LOW MVFR/IFR TONIGHT.
* MEDIUM IN TIMING OF WIND SHIFT THIS EVENING.
KJB
//OUTLOOK FOR ORD/MDW FOR 00Z THURSDAY-12Z TUESDAY...UPDATED 12Z...
WEDNESDAY NIGHT THROUGH SATURDAY...VFR. PRIMARILY NORTHEAST/EAST
WINDS.
SUNDAY...CHC THUNDERSTORMS.
MONDAY...SLT CHC THUNDERSTORMS.
BMD
&&
.MARINE...
251 AM CDT
A COLD FRONT CURRENTLY DRAPED ACROSS THE NORTHERN THIRD OF THE LAKE
WILL CONTINUE TO SAG SOUTH THROUGH THE DAY...CLEARING THE SOUTH END
OF THE LAKE THIS EVENING. AHEAD OF THE FRONT...SOUTH TO SOUTHWEST
WINDS HAVE TRANSPORTED MOIST AIR OVER THE COOL STABLE WATERS OF THE
LAKE RESULTING IN DENSE FOG DEVELOPING OVER THE OPEN WATERS. ONCE
WINDS TURN NORTHERLY BEHIND THE FRONT...DRIER AIR WILL GRADUALLY
ERODE THE FOG AND VISIBILITY SHOULD IMPROVE FROM THE NORTH THIS
EVENING AND TONIGHT. SOME OF THIS FOG MAY BE SHUNTED BACK INTO THE
IL/IN NEARSHORE WATERS THIS EVENING AS THE FRONT PUSHES ACROSS. HIGH
PRESSURE BUILDS ACROSS THE GREAT LAKES MIDWEEK AND REMAINS SITUATED
THERE FOR THE REMAINDER OF THE WEEK WITH A PERIOD OF MODEST NORTH TO
NORTHEAST FLOW THROUGH FRIDAY. WINDS MAY BE LIGHT ENOUGH TO TURN A
LAKE BREEZE RESULTING IN ONSHORE FLOW IN THE AFTERNOON AND EVENING
HOURS EACH DAY. WINDS BEGIN TO VEER BACK TOWARDS THE SOUTH SATURDAY
AS LOW PRESSURE DEEPENS OVER THE PLAINS AND LIFTS A WARM FRONT BACK
ACROSS LAKE MICHIGAN THIS WEEKEND.
BMD
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...DENSE FOG ADVISORY...LMZ261-LMZ362-LMZ364-LMZ366-LMZ563-LMZ565-
LMZ567-LMZ868 UNTIL 3 PM TUESDAY.
DENSE FOG ADVISORY...LMZ080-LMZ669-LMZ671-LMZ673-LMZ675-LMZ777-
LMZ779-LMZ870-LMZ872-LMZ874-LMZ876-LMZ878 UNTIL 9 PM
TUESDAY.
&&
$$
VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
WWW.FACEBOOK.COM/US.NATIONALWEATHERSERVICE.CHICAGO.GOV
WWW.TWITTER.COM/NWSCHICAGO
WWW.YOUTUBE.COM/NWSCHICAGO
Area Forecast Discussion
National Weather Service Lincoln IL
1237 PM CDT Tue May 27 2014
.DISCUSSION...
ISSUED 1040 AM CDT Tue May 27 2014
Not much of a shift overall from yesterday. Storm system brewing
over the Southern Plains and warm humid air surging into the FA
this morning. Broken mid/high clouds out there, but still expecting the
development of a cu field as well. Diurnally driven showers and
thunder this afternoon likely, though coverage will be in the
scattered range. Have reduced pops overall to slightly better
reflect the similarity to yesterday. Going forecast is doing well
for the afternoon as far as temperatures into the 80s but a couple
degrees cooler than yesterday with a little more in the way of
cloud cover. Updates out momentarily.
&&
.AVIATION...
ISSUED 1234 PM CDT Tue May 27 2014
Forecast almost identical to 24 hrs ago, with more west/southwesterly
winds. Continuing VFR conditions through the forecast because of
uncertainty as to where afternoon showers may affect llvl RH. Cu
slow to form over this region under existing mid/high cloud cover. Afternoon
ts will be scattered enough to keep to a vc mention until storms
form. Sct cu will diminish with loss of daytime heating, but
likely linger a mention of a sct group before the broken mid/high.
Similar through the morning. Surface dew points will need to climb
a couple more degrees before amending for an MVFR vis drop for the
early morning hours.
HJS
&&
.PREV DISCUSSION...
ISSUED 215 AM CDT Tue May 27 2014
Weak surface low centered just east of Minneapolis early this
morning, with a boundary extending southwest into north central
Iowa. Earlier showers/storms in southwest Illinois, associated
with a weak trough around 925 mb, have largely faded with just
some sprinkles perhaps in the far southwest CWA west of
Jacksonville. Persistent large upper low evident on water vapor
imagery continues to make slow progress east-southeast, and was
centered over the Texas panhandle, with a broad trough extending
northward through the Plains.
SHORT TERM...Today through Thursday:
Still not much change in the weather pattern during this part of
the forecast. Main concern will be with diurnal showers and
storms. While the upper low will not directly impact us, it still
will have a bit of influence with a shortwave in the northern
stream, which will slip a backdoor cold front through the forecast
area on Wednesday. This front will bring slightly cooler
temperatures by mid week, namely lower 80s vs mid/upper 80s.
Similar to yesterday, scattered showers and thunderstorms are
expected to develop late morning, becoming more numerous in the
afternoon before dying off in the evening. Instability expected to
be rather modest, with the NAM and RAP keeping CAPE`s over most of
the forecast area below 1000 J/kg, so severe weather is of little
concern. However, precipitable water values around 1.6 inches
would favor some heavier downpours, but the scattered nature of
the storms will result in widely varying precipitation amounts.
Somewhat better rain chances expected on Wednesday as the front
arrives and provides some better forcing, and have increased
PoP`s to around 60% across the central third of the CWA. For
Thursday, the evening model runs have started a trend of shifting
the rain chances a bit further south due to the movement of the
front. Have reduced rain chances to around 20% northwest of the
Illinois River as a result, but continued the mention of scattered
storms elsewhere.
LONG TERM...Friday through Monday:
Upper ridge will be drifting through the Mississippi Valley late
in the week, flattening out early next week. Our next rain chances
will be focused on a shortwave that will ride along the top of
what`s left of the ridge late in the weekend. Main rain chances
with this feature look to be Sunday afternoon and evening. The
model solutions then begin to diverge early next week, with the
ECMWF wetter, but its solution has also shifted its rain/frontal
boundary quite a bit further north than the last run. Still looks
to be scattered storms in the general area on Monday with either
this solution or the GFS solution.
Geelhart
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
1114 AM CDT TUE MAY 27 2014
.DISCUSSION...
334 AM CDT
FORECAST CONCERNS CONTINUE TO FOCUS ON PRECIP/CONVECTION TRENDS
TODAY INTO TONIGHT...AS WEAK COLD FRONT SAGS SOUTH INTO THE AREA.
SHARP COOLING AND FOG LIKELY ALONG THE LAKE AS WINDS SHIFT NORTHEAST
LATER TODAY. FRONT CONTINUES TO PUSH VERY SLOWLY SOUTH OF THE
FORECAST AREA WEDNESDAY-THURSDAY WITH SCATTERED MAINLY DIURNAL
SHOWERS/STORMS LINGERING ACROSS CENTRAL IL/IN THROUGH MID-WEEK.
TEMPS COOL A BIT BEHIND THE FRONT...THOUGH MAINLY COOLER NEAR LAKE
MICHIGAN AS WINDS TURN NORTHEAST. TEMPS AWAY FROM THE LAKE NEAR
NORMAL...WITH A WARMING TREND INTO THE WEEKEND.
EARLY MORNING SURFACE MAP DEPICTS A WEAK AREA OF LOW PRESSURE OVER
THE UPPER MISSISSIPPI VALLEY...WITH A NEARLY STATIONARY COLD FRONTAL
BOUNDARY EXTENDING ACROSS NORTH CENTRAL WI TO NEAR THE SOO. ALOFT...
CLOSED UPPER LOW WELL TO OUR SOUTH CONTINUES TO DRIFT ALONG THE
TEXAS/OKLAHOMA BORDER...WHILE A SLOW MOVING MID-LEVEL TROUGH WAS
NOTED OVER MN/IA ALONG THE SOUTHERN PERIPHERY OF FASTER FLOW ALONG
THE CANADIAN BORDER. LITTLE IN THE WAY OF SIGNIFICANT FORCING NOTED
WITH JUST A COUPLE OF WEAK VORT MAXIMA MOVING THROUGH MODEST FLOW
ALOFT. EXPECTATION IS THAT DIURNAL INSTABILITY AND APPROACH OF THE
COLD FRONT FROM THE NORTH THIS AFTERNOON WILL BE THE BEST FOCUS FOR
RENEWED SHOWER AND THUNDERSTORM DEVELOPMENT. RECENT RUNS OF THE HRRR
CONCUR...AND HAVE MAINTAINED ONLY SOME SLIGHT CHANCE POPS FOR
ISOLATED SHRA/TSRA THIS MORNING. THUNDERSTORM COVERAGE THEN EXPECTED
TO INCREASE ALONG/SOUTH OF THE APPROACHING FRONT ACROSS SOUTHERN WI
AND NORTHERN IL DURING THE AFTERNOON. MODELS HAVE CONTINUED TO SHOW
SOME DIFFERENCES IN THE DETAILS OF THE SPEED OF THE WEAK FRONT...
WITH A PREFERENCE FOR SLIGHTLY FASTER GFS/LOCAL WRF SOLUTIONS WHICH
SLIDE FRONT DOWN THE ILLINOIS LAKE SHORE DURING THE LATE AFTERNOON
HOURS. WINDS SHIFTING NORTHEAST BEHIND THE FRONT ARE EXPECTED TO
BRING QUICK COOLING (NEAR 80 DROPPING INTO 60S) TO THE NORTH SHORE
AND ADJACENT AREAS BEFORE EVENING...ALONG WITH SOME FOG DUE TO COOL
LAKE AND HUMID AIR MASS. FORECAST SOUNDINGS INDICATE MLCAPES AROUND
500 J/KG WITH WEAK FLOW ALOFT CONTRIBUTING TO WEAK DEEP LAYER SHEAR.
THUS NOT EXPECTING SEVERE STORMS...THOUGH PRECIPITABLE WATER VALUES
ABOVE 1.50" PER 00Z DVN SOUNDING INDICATE HEAVY DOWNPOURS POSSIBLE.
STORMS SHOULD DECREASE IN COVERAGE WITH SUNSET...AS DIURNAL
INSTABILITY DECREASES.
FRONT CONTINUES TO PUSH SLOWLY SOUTH ACROSS THE FORECAST AREA
WEDNESDAY...MOVING JUST SOUTH OF THE CWA BY WEDNESDAY NIGHT. WITH A
WEAK MID-LEVEL TROUGH OVERHEAD THE FRONTAL BOUNDARY IS EXPECTED TO
AGAIN BE A FOCUS FOR SCATTERED DIURNAL CONVECTION...MAINLY SOUTH OF
I-80 CORRIDOR. PRECIP THREAT SHOULD DIMINISH SIGNIFICANTLY FARTHER
NORTH...AS COOLER MORE STABLE AIR SPREADS IN FROM THE NORTHEAST.
AFTER MAX TEMPS IN THE LOW-MID 80S TODAY...READINGS EXPECTED TO
RANGE FROM THE MID 60S ALONG THE LAKE TO THE MID-UPPER 70S
WEDNESDAY...WITH LOW 80S SOUTH CLOSER TO THE FRONT. UPPER RIDGE THEN
DEVELOPS AND BUILDS OVER THE REGION THURSDAY-FRIDAY DOWNSTREAM OF
HIGHLY AMPLIFIED WEST COAST TROUGH. SURFACE HIGH PRESSURE RIDGE OVER
THE NORTHERN/WESTERN LAKES WILL KEEP LAKE COOLING IN PLAY THROUGH
FRIDAY WHILE TEMPS OTHERWISE MODERATE BACK INTO THE 80S FARTHER
INLAND BENEATH BUILDING UPPER RIDGE. EFFECT OF LAKE COOLING WILL
DIMINISH INTO THE WEEKEND AS SURFACE WINDS GRADUALLY BECOME MORE
SOUTHEAST THAN NORTHEAST.
THE NEXT CHANCE OF SHOWERS AND THUNDERSTORMS WILL ARRIVE SUNDAY INTO
MONDAY AS JET STREAK AND SHORT WAVE PROPAGATE ACROSS THE UPPER
MIDWEST AND FLATTEN UPPER RIDGE. ECMWF REMAINS DEEPER THAN GFS AND
GEFS MEMBERS WITH THE SHORT WAVE...AND IN BRINGING COLD FRONT ACROSS
THE AREA SUNDAY NIGHT. GFS KEEPS FRONT TO OUR NORTH THROUGH
MONDAY...WITH SUPPORT OF GEFS ENSEMBLES WHICH MAINTAIN CONSISTENCY
AND SHOW FAIRLY MINIMAL SPREAD. THUS CONFIDENCE FAIRLY LOW IN
PICKING EITHER EXTREME IN VARIOUS SOLUTIONS AT THIS DISTANCE...AND
FORECAST FOR SUNDAY/MONDAY REPRESENT A BLEND TOWARD THE GEFS.
RATZER
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 16Z...
* SCATTERED THUNDERSTORMS THIS AFTERNOON/EVENING.
* SW WINDS SHIFTING TO THE NE BY THIS EVENING.
* LOW MVFR TO IFR CIGS DEVELOPING LATER THIS EVENING/OVERNIGHT.
BMD/KB
//DISCUSSION...UPDATED 12Z...
A COLD FRONT IS STARTING TO SAG SOUTH ACROSS LAKE MICHIGAN THIS
MORNING. OUT AHEAD OF THE FRONT...SOUTHWEST WINDS WILL PREVAIL TODAY
WITH PRIMARILY VFR CONDITIONS OUTSIDE OF SOME PATCHY FOG THIS THIS
MORNING. WITH DAYTIME HEATING...MODERATE INSTABILITY WILL BUILD
ACROSS THE REGION ALLOWING SCATTERED THUNDERSTORMS TO DEVELOP. WITH
LITTLE TO NO CAP IN PLACE TODAY...CANNOT RULE OUT A THUNDERSTORM
IMPACTING THE TERMINALS AT ANY TIME THIS AFTERNOON...BUT THE CHANCES
APPEAR MOST FAVORABLE MID TO LATE AFTERNOON AS THE COLD FRONT
APPROACHES. THE FRONT WILL LIKELY SURGE DOWN THE LAKE WITH AN
ENHANCED LAKE BREEZE TURNING WINDS NORTHEASTERLY LATE THIS AFTERNOON
OR EARLY EVENING. THE THUNDER THREAT SHOULD DISSIPATE ONCE THE WINDS
TURN NORTHEASTERLY...BUT THEN THE CONCERN WILL TURN TO LOWER VSBY
AND CIGS. DENSE FOG IS IN PLACE ACROSS LAKE MICHIGAN...AND MAY SPILL
INLAND AS THE WINDS TURN LATER TODAY...LIFTING TO AN IFR OR LOWER
MVFR DECK AS IT REACHES THE TERMINALS THIS EVENING/TONIGHT.
CONFIDENCE IS LOW HOW THIS WILL PLAY OUT WITH CONSIDERABLE
DIFFERENCES IN THE GUIDANCE. WILL MAINTAIN MENTION OF MVFR CIGS IN
THE MEANTIME.
BMD
//ORD AND MDW CONFIDENCE...UPDATED 16Z...
* HIGH WITH SOME WIDELY SCATTERED THUNDERSTORMS LATER TODAY.
* MEDIUM IN TIMING AND ACTUAL IMPACTS AT TERMINALS.
* LOW MEDIUM IN LOW MVFR/IFR TONIGHT.
* MEDIUM IN TIMING OF WIND SHIFT THIS EVENING.
BMD/KB
//OUTLOOK FOR ORD/MDW FOR 00Z THURSDAY-12Z TUESDAY...UPDATED 12Z...
WEDNESDAY NIGHT THROUGH SATURDAY...VFR. PRIMARILY NORTHEAST/EAST
WINDS.
SUNDAY...CHC THUNDERSTORMS.
MONDAY...SLT CHC THUNDERSTORMS.
BMD
&&
.MARINE...
251 AM CDT
A COLD FRONT CURRENTLY DRAPED ACROSS THE NORTHERN THIRD OF THE LAKE
WILL CONTINUE TO SAG SOUTH THROUGH THE DAY...CLEARING THE SOUTH END
OF THE LAKE THIS EVENING. AHEAD OF THE FRONT...SOUTH TO SOUTHWEST
WINDS HAVE TRANSPORTED MOIST AIR OVER THE COOL STABLE WATERS OF THE
LAKE RESULTING IN DENSE FOG DEVELOPING OVER THE OPEN WATERS. ONCE
WINDS TURN NORTHERLY BEHIND THE FRONT...DRIER AIR WILL GRADUALLY
ERODE THE FOG AND VISIBILITY SHOULD IMPROVE FROM THE NORTH THIS
EVENING AND TONIGHT. SOME OF THIS FOG MAY BE SHUNTED BACK INTO THE
IL/IN NEARSHORE WATERS THIS EVENING AS THE FRONT PUSHES ACROSS. HIGH
PRESSURE BUILDS ACROSS THE GREAT LAKES MIDWEEK AND REMAINS SITUATED
THERE FOR THE REMAINDER OF THE WEEK WITH A PERIOD OF MODEST NORTH TO
NORTHEAST FLOW THROUGH FRIDAY. WINDS MAY BE LIGHT ENOUGH TO TURN A
LAKE BREEZE RESULTING IN ONSHORE FLOW IN THE AFTERNOON AND EVENING
HOURS EACH DAY. WINDS BEGIN TO VEER BACK TOWARDS THE SOUTH SATURDAY
AS LOW PRESSURE DEEPENS OVER THE PLAINS AND LIFTS A WARM FRONT BACK
ACROSS LAKE MICHIGAN THIS WEEKEND.
BMD
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...DENSE FOG ADVISORY...LMZ261-LMZ362-LMZ364-LMZ366-LMZ563-LMZ565-
LMZ567-LMZ868 UNTIL 3 PM TUESDAY.
DENSE FOG ADVISORY...LMZ080-LMZ669-LMZ671-LMZ673-LMZ675-LMZ777-
LMZ779-LMZ870-LMZ872-LMZ874-LMZ876-LMZ878 UNTIL 9 PM
TUESDAY.
&&
$$
VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
WWW.FACEBOOK.COM/US.NATIONALWEATHERSERVICE.CHICAGO.GOV
WWW.TWITTER.COM/NWSCHICAGO
WWW.YOUTUBE.COM/NWSCHICAGO
Area Forecast Discussion
National Weather Service Lincoln IL
1047 AM CDT Tue May 27 2014
.DISCUSSION...
ISSUED 1040 AM CDT Tue May 27 2014
Not much of a shift overall from yesterday. Storm system brewing
over the Southern Plains and warm humid air surging into the FA
this morning. Broken mid/high clouds out there, but still expecting the
development of a cu field as well. Diurnally driven showers and
thunder this afternoon likely, though coverage will be in the
scattered range. Have reduced pops overall to slightly better
reflect the similarity to yesterday. Going forecast is doing well
for the afternoon as far as temperatures into the 80s but a couple
degrees cooler than yesterday with a little more in the way of
cloud cover. Updates out momentarily.
HJS
&&
.AVIATION...
ISSUED 600 AM CDT Tue May 27 2014
VFR conditions expected into tonight with the possibility of some
MVFR vsbys in fog. Any convection that affects a TAF site this
afternoon or early this evening will be capable of bringing cigs
and vsbys down to MVFR for a brief time, but coverage expected
to be too limited once again so will continue with VCTS at or
just aftr 20z. Forecast soundings suggest cumulus to form aftr
15z with bases in the 4000-5000 foot range before dissipating
aftr 23z. Overnight, we may see some MVFR vsbys in fog/hz develop
aftr 09z, especially at any location that receives rainfall
today or this evening.
Surface winds will continue from a southwest direction today at
10 to 15 kts with a few gusts up to 20 kts this afternoon. A cold
front will shift south into our far northern areas late tonight
but it appears the boundary will stay just north of our TAF sites.
Winds overnight will be from a southwest to west direction at 5 to
10 kts.
Smith
&&
.PREV DISCUSSION...
ISSUED 215 AM CDT Tue May 27 2014
Weak surface low centered just east of Minneapolis early this
morning, with a boundary extending southwest into north central
Iowa. Earlier showers/storms in southwest Illinois, associated
with a weak trough around 925 mb, have largely faded with just
some sprinkles perhaps in the far southwest CWA west of
Jacksonville. Persistent large upper low evident on water vapor
imagery continues to make slow progress east-southeast, and was
centered over the Texas panhandle, with a broad trough extending
northward through the Plains.
SHORT TERM...Today through Thursday:
Still not much change in the weather pattern during this part of
the forecast. Main concern will be with diurnal showers and
storms. While the upper low will not directly impact us, it still
will have a bit of influence with a shortwave in the northern
stream, which will slip a backdoor cold front through the forecast
area on Wednesday. This front will bring slightly cooler
temperatures by mid week, namely lower 80s vs mid/upper 80s.
Similar to yesterday, scattered showers and thunderstorms are
expected to develop late morning, becoming more numerous in the
afternoon before dying off in the evening. Instability expected to
be rather modest, with the NAM and RAP keeping CAPE`s over most of
the forecast area below 1000 J/kg, so severe weather is of little
concern. However, precipitable water values around 1.6 inches
would favor some heavier downpours, but the scattered nature of
the storms will result in widely varying precipitation amounts.
Somewhat better rain chances expected on Wednesday as the front
arrives and provides some better forcing, and have increased
PoP`s to around 60% across the central third of the CWA. For
Thursday, the evening model runs have started a trend of shifting
the rain chances a bit further south due to the movement of the
front. Have reduced rain chances to around 20% northwest of the
Illinois River as a result, but continued the mention of scattered
storms elsewhere.
LONG TERM...Friday through Monday:
Upper ridge will be drifting through the Mississippi Valley late
in the week, flattening out early next week. Our next rain chances
will be focused on a shortwave that will ride along the top of
what`s left of the ridge late in the weekend. Main rain chances
with this feature look to be Sunday afternoon and evening. The
model solutions then begin to diverge early next week, with the
ECMWF wetter, but its solution has also shifted its rain/frontal
boundary quite a bit further north than the last run. Still looks
to be scattered storms in the general area on Monday with either
this solution or the GFS solution.
Geelhart
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
639 AM CDT TUE MAY 27 2014
.DISCUSSION...
334 AM CDT
FORECAST CONCERNS CONTINUE TO FOCUS ON PRECIP/CONVECTION TRENDS
TODAY INTO TONIGHT...AS WEAK COLD FRONT SAGS SOUTH INTO THE AREA.
SHARP COOLING AND FOG LIKELY ALONG THE LAKE AS WINDS SHIFT NORTHEAST
LATER TODAY. FRONT CONTINUES TO PUSH VERY SLOWLY SOUTH OF THE
FORECAST AREA WEDNESDAY-THURSDAY WITH SCATTERED MAINLY DIURNAL
SHOWERS/STORMS LINGERING ACROSS CENTRAL IL/IN THROUGH MID-WEEK.
TEMPS COOL A BIT BEHIND THE FRONT...THOUGH MAINLY COOLER NEAR LAKE
MICHIGAN AS WINDS TURN NORTHEAST. TEMPS AWAY FROM THE LAKE NEAR
NORMAL...WITH A WARMING TREND INTO THE WEEKEND.
EARLY MORNING SURFACE MAP DEPICTS A WEAK AREA OF LOW PRESSURE OVER
THE UPPER MISSISSIPPI VALLEY...WITH A NEARLY STATIONARY COLD FRONTAL
BOUNDARY EXTENDING ACROSS NORTH CENTRAL WI TO NEAR THE SOO. ALOFT...
CLOSED UPPER LOW WELL TO OUR SOUTH CONTINUES TO DRIFT ALONG THE
TEXAS/OKLAHOMA BORDER...WHILE A SLOW MOVING MID-LEVEL TROUGH WAS
NOTED OVER MN/IA ALONG THE SOUTHERN PERIPHERY OF FASTER FLOW ALONG
THE CANADIAN BORDER. LITTLE IN THE WAY OF SIGNIFICANT FORCING NOTED
WITH JUST A COUPLE OF WEAK VORT MAXIMA MOVING THROUGH MODEST FLOW
ALOFT. EXPECTATION IS THAT DIURNAL INSTABILITY AND APPROACH OF THE
COLD FRONT FROM THE NORTH THIS AFTERNOON WILL BE THE BEST FOCUS FOR
RENEWED SHOWER AND THUNDERSTORM DEVELOPMENT. RECENT RUNS OF THE HRRR
CONCUR...AND HAVE MAINTAINED ONLY SOME SLIGHT CHANCE POPS FOR
ISOLATED SHRA/TSRA THIS MORNING. THUNDERSTORM COVERAGE THEN EXPECTED
TO INCREASE ALONG/SOUTH OF THE APPROACHING FRONT ACROSS SOUTHERN WI
AND NORTHERN IL DURING THE AFTERNOON. MODELS HAVE CONTINUED TO SHOW
SOME DIFFERENCES IN THE DETAILS OF THE SPEED OF THE WEAK FRONT...
WITH A PREFERENCE FOR SLIGHTLY FASTER GFS/LOCAL WRF SOLUTIONS WHICH
SLIDE FRONT DOWN THE ILLINOIS LAKE SHORE DURING THE LATE AFTERNOON
HOURS. WINDS SHIFTING NORTHEAST BEHIND THE FRONT ARE EXPECTED TO
BRING QUICK COOLING (NEAR 80 DROPPING INTO 60S) TO THE NORTH SHORE
AND ADJACENT AREAS BEFORE EVENING...ALONG WITH SOME FOG DUE TO COOL
LAKE AND HUMID AIR MASS. FORECAST SOUNDINGS INDICATE MLCAPES AROUND
500 J/KG WITH WEAK FLOW ALOFT CONTRIBUTING TO WEAK DEEP LAYER SHEAR.
THUS NOT EXPECTING SEVERE STORMS...THOUGH PRECIPITABLE WATER VALUES
ABOVE 1.50" PER 00Z DVN SOUNDING INDICATE HEAVY DOWNPOURS POSSIBLE.
STORMS SHOULD DECREASE IN COVERAGE WITH SUNSET...AS DIURNAL
INSTABILITY DECREASES.
FRONT CONTINUES TO PUSH SLOWLY SOUTH ACROSS THE FORECAST AREA
WEDNESDAY...MOVING JUST SOUTH OF THE CWA BY WEDNESDAY NIGHT. WITH A
WEAK MID-LEVEL TROUGH OVERHEAD THE FRONTAL BOUNDARY IS EXPECTED TO
AGAIN BE A FOCUS FOR SCATTERED DIURNAL CONVECTION...MAINLY SOUTH OF
I-80 CORRIDOR. PRECIP THREAT SHOULD DIMINISH SIGNIFICANTLY FARTHER
NORTH...AS COOLER MORE STABLE AIR SPREADS IN FROM THE NORTHEAST.
AFTER MAX TEMPS IN THE LOW-MID 80S TODAY...READINGS EXPECTED TO
RANGE FROM THE MID 60S ALONG THE LAKE TO THE MID-UPPER 70S
WEDNESDAY...WITH LOW 80S SOUTH CLOSER TO THE FRONT. UPPER RIDGE THEN
DEVELOPS AND BUILDS OVER THE REGION THURSDAY-FRIDAY DOWNSTREAM OF
HIGHLY AMPLIFIED WEST COAST TROUGH. SURFACE HIGH PRESSURE RIDGE OVER
THE NORTHERN/WESTERN LAKES WILL KEEP LAKE COOLING IN PLAY THROUGH
FRIDAY WHILE TEMPS OTHERWISE MODERATE BACK INTO THE 80S FARTHER
INLAND BENEATH BUILDING UPPER RIDGE. EFFECT OF LAKE COOLING WILL
DIMINISH INTO THE WEEKEND AS SURFACE WINDS GRADUALLY BECOME MORE
SOUTHEAST THAN NORTHEAST.
THE NEXT CHANCE OF SHOWERS AND THUNDERSTORMS WILL ARRIVE SUNDAY INTO
MONDAY AS JET STREAK AND SHORT WAVE PROPAGATE ACROSS THE UPPER
MIDWEST AND FLATTEN UPPER RIDGE. ECMWF REMAINS DEEPER THAN GFS AND
GEFS MEMBERS WITH THE SHORT WAVE...AND IN BRINGING COLD FRONT ACROSS
THE AREA SUNDAY NIGHT. GFS KEEPS FRONT TO OUR NORTH THROUGH
MONDAY...WITH SUPPORT OF GEFS ENSEMBLES WHICH MAINTAIN CONSISTENCY
AND SHOW FAIRLY MINIMAL SPREAD. THUS CONFIDENCE FAIRLY LOW IN
PICKING EITHER EXTREME IN VARIOUS SOLUTIONS AT THIS DISTANCE...AND
FORECAST FOR SUNDAY/MONDAY REPRESENT A BLEND TOWARD THE GEFS.
RATZER
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 12Z...
* SCATTERED THUNDERSTORMS THIS AFTERNOON/EVENING.
* SW WINDS SHIFTING TO THE NE THIS EVENING.
BMD
//DISCUSSION...UPDATED 12Z...
A COLD FRONT IS STARTING TO SAG SOUTH ACROSS LAKE MICHIGAN THIS
MORNING. OUT AHEAD OF THE FRONT...SOUTHWEST WINDS WILL PREVAIL TODAY
WITH PRIMARILY VFR CONDITIONS OUTSIDE OF SOME PATCHY FOG THIS THIS
MORNING. WITH DAYTIME HEATING...MODERATE INSTABILITY WILL BUILD
ACROSS THE REGION ALLOWING SCATTERED THUNDERSTORMS TO DEVELOP. WITH
LITTLE TO NO CAP IN PLACE TODAY...CANNOT RULE OUT A THUNDERSTORM
IMPACTING THE TERMINALS AT ANY TIME THIS AFTERNOON...BUT THE CHANCES
APPEAR MOST FAVORABLE MID TO LATE AFTERNOON AS THE COLD FRONT
APPROACHES. THE FRONT WILL LIKELY SURGE DOWN THE LAKE WITH AN
ENHANCED LAKE BREEZE TURNING WINDS NORTHEASTERLY LATE THIS AFTERNOON
OR EARLY EVENING. THE THUNDER THREAT SHOULD DISSIPATE ONCE THE WINDS
TURN NORTHEASTERLY...BUT THEN THE CONCERN WILL TURN TO LOWER VSBY
AND CIGS. DENSE FOG IS IN PLACE ACROSS LAKE MICHIGAN...AND MAY SPILL
INLAND AS THE WINDS TURN LATER TODAY...LIFTING TO AN IFR OR LOWER
MVFR DECK AS IT REACHES THE TERMINALS THIS EVENING/TONIGHT.
CONFIDENCE IS LOW HOW THIS WILL PLAY OUT WITH CONSIDERABLE
DIFFERENCES IN THE GUIDANCE. WILL MAINTAIN MENTION OF MVFR CIGS IN
THE MEANTIME.
BMD
//ORD AND MDW CONFIDENCE...UPDATED 12Z...
* HIGH CONFIDENCE IN SCATTERED THUNDERSTORMS...MEDIUM CONFIDENCE
IN TIMING IMPACTS AT TERMINALS.
* HIGH CONFIDENCE IN VFR CONDITIONS TODAY...LOW CONFIDENCE IN IFR
TONIGHT.
* MEDIUM CONFIDENCE IN TIMING OF WIND SHIFT THIS EVENING.
BMD
//OUTLOOK FOR ORD/MDW FOR 00Z THURSDAY-12Z TUESDAY...UPDATED 12Z...
WEDNESDAY NIGHT THROUGH SATURDAY...VFR. PRIMARILY NORTHEAST/EAST
WINDS.
SUNDAY...CHC THUNDERSTORMS.
MONDAY...SLT CHC THUNDERSTORMS.
BMD
&&
.MARINE...
251 AM CDT
A COLD FRONT CURRENTLY DRAPED ACROSS THE NORTHERN THIRD OF THE LAKE
WILL CONTINUE TO SAG SOUTH THROUGH THE DAY...CLEARING THE SOUTH END
OF THE LAKE THIS EVENING. AHEAD OF THE FRONT...SOUTH TO SOUTHWEST
WINDS HAVE TRANSPORTED MOIST AIR OVER THE COOL STABLE WATERS OF THE
LAKE RESULTING IN DENSE FOG DEVELOPING OVER THE OPEN WATERS. ONCE
WINDS TURN NORTHERLY BEHIND THE FRONT...DRIER AIR WILL GRADUALLY
ERODE THE FOG AND VISIBILITY SHOULD IMPROVE FROM THE NORTH THIS
EVENING AND TONIGHT. SOME OF THIS FOG MAY BE SHUNTED BACK INTO THE
IL/IN NEARSHORE WATERS THIS EVENING AS THE FRONT PUSHES ACROSS. HIGH
PRESSURE BUILDS ACROSS THE GREAT LAKES MIDWEEK AND REMAINS SITUATED
THERE FOR THE REMAINDER OF THE WEEK WITH A PERIOD OF MODEST NORTH TO
NORTHEAST FLOW THROUGH FRIDAY. WINDS MAY BE LIGHT ENOUGH TO TURN A
LAKE BREEZE RESULTING IN ONSHORE FLOW IN THE AFTERNOON AND EVENING
HOURS EACH DAY. WINDS BEGIN TO VEER BACK TOWARDS THE SOUTH SATURDAY
AS LOW PRESSURE DEEPENS OVER THE PLAINS AND LIFTS A WARM FRONT BACK
ACROSS LAKE MICHIGAN THIS WEEKEND.
BMD
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...DENSE FOG ADVISORY...LMZ261-LMZ362-LMZ364-LMZ366-LMZ563-LMZ565-
LMZ567-LMZ868 UNTIL 3 PM TUESDAY.
DENSE FOG ADVISORY...LMZ080-LMZ669-LMZ671-LMZ673-LMZ675-LMZ777-
LMZ779-LMZ870-LMZ872-LMZ874-LMZ876-LMZ878 UNTIL 9 PM
TUESDAY.
&&
$$
VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
WWW.FACEBOOK.COM/US.NATIONALWEATHERSERVICE.CHICAGO.GOV
WWW.TWITTER.COM/NWSCHICAGO
WWW.YOUTUBE.COM/NWSCHICAGO
Area Forecast Discussion
National Weather Service Lincoln IL
602 AM CDT Tue May 27 2014
.DISCUSSION...
ISSUED 215 AM CDT Tue May 27 2014
Weak surface low centered just east of Minneapolis early this
morning, with a boundary extending southwest into north central
Iowa. Earlier showers/storms in southwest Illinois, associated
with a weak trough around 925 mb, have largely faded with just
some sprinkles perhaps in the far southwest CWA west of
Jacksonville. Persistent large upper low evident on water vapor
imagery continues to make slow progress east-southeast, and was
centered over the Texas panhandle, with a broad trough extending
northward through the Plains.
SHORT TERM...Today through Thursday:
Still not much change in the weather pattern during this part of
the forecast. Main concern will be with diurnal showers and
storms. While the upper low will not directly impact us, it still
will have a bit of influence with a shortwave in the northern
stream, which will slip a backdoor cold front through the forecast
area on Wednesday. This front will bring slightly cooler
temperatures by mid week, namely lower 80s vs mid/upper 80s.
Similar to yesterday, scattered showers and thunderstorms are
expected to develop late morning, becoming more numerous in the
afternoon before dying off in the evening. Instability expected to
be rather modest, with the NAM and RAP keeping CAPE`s over most of
the forecast area below 1000 J/kg, so severe weather is of little
concern. However, precipitable water values around 1.6 inches
would favor some heavier downpours, but the scattered nature of
the storms will result in widely varying precipitation amounts.
Somewhat better rain chances expected on Wednesday as the front
arrives and provides some better forcing, and have increased
PoP`s to around 60% across the central third of the CWA. For
Thursday, the evening model runs have started a trend of shifting
the rain chances a bit further south due to the movement of the
front. Have reduced rain chances to around 20% northwest of the
Illinois River as a result, but continued the mention of scattered
storms elsewhere.
LONG TERM...Friday through Monday:
Upper ridge will be drifting through the Mississippi Valley late
in the week, flattening out early next week. Our next rain chances
will be focused on a shortwave that will ride along the top of
what`s left of the ridge late in the weekend. Main rain chances
with this feature look to be Sunday afternoon and evening. The
model solutions then begin to diverge early next week, with the
ECMWF wetter, but its solution has also shifted its rain/frontal
boundary quite a bit further north than the last run. Still looks
to be scattered storms in the general area on Monday with either
this solution or the GFS solution.
Geelhart
&&
.AVIATION...
ISSUED 600 AM CDT Tue May 27 2014
VFR conditions expected into tonight with the possibility of some
MVFR vsbys in fog. Any convection that affects a TAF site this
afternoon or early this evening will be capable of bringing cigs
and vsbys down to MVFR for a brief time, but coverage expected
to be too limited once again so will continue with VCTS at or
just aftr 20z. Forecast soundings suggest cumulus to form aftr
15z with bases in the 4000-5000 foot range before dissipating
aftr 23z. Overnight, we may see some MVFR vsbys in fog/hz develop
aftr 09z, especially at any location that receives rainfall
today or this evening.
Surface winds will continue from a southwest direction today at
10 to 15 kts with a few gusts up to 20 kts this afternoon. A cold
front will shift south into our far northern areas late tonight
but it appears the boundary will stay just north of our TAF sites.
Winds overnight will be from a southwest to west direction at 5 to
10 kts.
Smith
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
252 AM CDT TUE MAY 27 2014
.DISCUSSION...
854 PM CDT
SOME ADJUSTMENTS MADE TO THE REMAINDER OF THE TONIGHT
FORECAST...BUT MAINLY TO HOURLY TRENDS OF TEMPERATURES. DID
BUMP DOWN POPS FOR TUESDAY MORNING GIVEN DIURNAL TREND SEEN AND
EXPECTED IN CONVECTION. ALSO HAVE ENDED UP ADDING AREAS OF FOG
MENTION FOR TUESDAY NIGHT ALONG THE LAKE MICHIGAN
SHORE...INCLUDING DOWNTOWN CHICAGO...BASED ON UPSTREAM LAKE
MICHIGAN TRENDS FOR DENSE FOG ALREADY SEEN.
AN AREA OF ORGANIZED SHOWERS WITH EMBEDDED THUNDERSTORMS
CONTINUES TO MOVE EASTWARD ACROSS NORTHERN INDIANA...NOW BEING
MAINLY DRIVEN BY A COLD POOL. IMMEDIATELY BEHIND THIS...THE AIR
IS PRETTY WORKED OVER. FURTHER WEST HOWEVER...INTO NORTHWEST
IL...PLUME OF HIGHER PRECIPITABLE WATER AIR /1.68 INCHES AT DVN AT
00Z/ AND A SHORT WAVE NEAR THE MO/IA/IL INTERSECTION IS HELPING TO
SUSTAIN ISOLATED SHOWERS/STORMS. WHILE ELEVATED INSTABILITY
PERSISTS THROUGH THE NIGHT...BELIEVE THAT BEHIND THIS SHORT WAVE
IT WILL BE DIFFICULT TO GET THUNDER OVERNIGHT...BUT UNTIL THEN
COULD SEE SOME ISOLATED STRIKES ACROSS NORTH CENTRAL IL. A NOW
INVERSION IN THE LOW-LEVELS SHOULD PREVENT THE STRONGER
DOWNDRAFTS SUCH AS THOSE SEEN EARLIER.
COLD POOLS BROUGHT TEMPERATURES DOWN AND DEW POINTS UP EARLIER.
WITH THE CALM WINDS AM A LITTLE CONCERNED FOR FOG...HOWEVER
HIGH/MID CLOUD COVER WILL LIKELY PREVENT TEMPERATURES FROM
DROPPING VERY MUCH MORE. SO DO NOT EXPECT MANY HOURS OF SATURATION
THAT WOULD LEAD TO DENSE FOG...BUT WILL BE SOMETHING TO WATCH.
SPEAKING OF FOG...LATE DAY VISIBLE SATELLITE IMAGERY INDICATED
LIKELY FOG OVER MUCH OF NORTHERN LAKE MICHIGAN...WITH A SHIP
OBSERVATION INDICATING DENSE FOG. THE HIGH DEW POINT AIR OVER THE
COLD LAKE WATERS WILL LIKELY BLOSSOM DENSE FOG FOR MUCH OF THE
NORTH AND SOME PARTS OF THE SOUTHERN LAKE TONIGHT. AS THE FRONTAL
BOUNDARY SHIFTS SOUTH TUESDAY AFTERNOON AND EVENING...SOME OF THIS
FOG WILL LIKELY APPROACH THE SHORE AND COULD MOVE IN. THIS IS MOST
FAVORED AFTER SUNSET TUESDAY...AS ANY CONVECTION/COLD POOLS
DISSIPATE AND THE LAKE-ENHANCED FRONT PROGRESSES SOUTH.
MTF
//PREV DISCUSSION...
245 PM CDT
A TRANSITION TO LESS SETTLED WEATHER IS UNDERWAY THIS AFTERNOON.
MULTIPLE PERIODS OF SHOWERS AND THUNDERSTORMS ARE POSSIBLE FOR THE
ENTIRE AREA THIS AFTERNOON AS WELL AS TONIGHT AND TOMORROW...AND
FOR SOUTHERN PORTIONS OF THE AREA ON WEDNESDAY AND THURSDAY...BEFORE
DRIER WEATHER LOOKS POISED TO RETURN FOR FRIDAY INTO NEXT WEEKEND.
THE UPPER LEVEL RIDGE THAT RECENTLY BROUGHT US SEVERAL DAYS OF
LOVELY WEATHER IS NOW POSITIONED EAST OF THE FORECAST AREA THIS
AFTERNOON...WITH ITS AXIS RUNNING FROM THE EASTERN GULF THROUGH THE
CENTRAL GREAT LAKES. MULTIPLE SHORTWAVE IMPULSES...ROUGHLY
FOUR...RIDING OVER THIS RIDGE ARE EVIDENT ON THE WATER VAPOR
SATELLITE CHANNEL...WITH THE FIRST ALREADY MOVING INTO THE LOCAL
AREA AND SUPPORTING CONVECTIVE DEVELOPMENT.
MODELS MATCH SATELLITE DATA IN SHOWING THE FOURTH IN THIS SERIES OF
SHORTWAVES...MOVING OUT OF NORTHEAST TEXAS...AS BEING THE MOST
PRONOUNCED. THIS WOULD REACH THE AREA TOMORROW AFTERNOON...WHICH IN
CONJUNCTION WITH DIURNAL HEATING AND MID 60S DEWPOINTS...SUPPORTS
THE IDEA OF LIKELY POPS FOR MUCH OF THE AREA. IN BETWEEN...WILL
PLAN TO MAINTAIN GENERALLY 40 TO 50 PERCENT POPS TO ACCOUNT FOR THE
TWO INTERMEDIATE SHORTWAVES...THOUGH LOW LEVEL THERMODYNAMIC SUPPORT
WILL BE RELATIVELY LESS FAVORABLE DURING THE OVERNIGHT AND EARLY
MORNING HOURS. ACTIVITY OVER THE NEXT DAY OR SO WILL BE SOMEWHAT
UNFOCUSED WITH NO CLEAR SYNOPTIC BOUNDARIES TO ENHANCE CONVERGENCE.
BY TUESDAY NIGHT INTO WEDNESDAY THE PASSAGE OF A WEAK COLD FRONT
AHEAD OF A SURFACE RIDGE BUILDING IN FROM THE NORTH WILL TURN WINDS
NORTHEAST FOR MUCH OF THE AREA AND TRAP THE BETTER MOISTURE TO THE
SOUTH WHERE IT POOLS ALONG A WEST TO EAST FRONTAL ZONE. THIS
SUPPORTS THE GOING FORECAST WHICH HAS SLIGHT CHANCE TO CHANCE POPS
ALONG THE LAKE AND TOWARD THE WI LINE...AND CHANCE TO LIKELY POPS
INCREASING TOWARD CENTRAL IL AND WEST CENTRAL INDIANA. THE OTHER
EFFECT WILL BE COOLER TEMPERATURES STARTING WEDNESDAY AND
THURSDAY...ESPECIALLY IN AREAS NEAR THE LAKE.
BY FRIDAY INTO MOST OF NEXT WEEKEND...THE GFS AND ECMWF AGREE IN
FURTHER BUILDING THE UPPER RIDGE AND SURFACE HIGH ACROSS THE WESTERN
GREAT LAKES AND PUSHING THE GULF MOISTURE WEST OF THE AREA INTO THE
MISSOURI VALLEY. MOISTURE AND CHANCE POPS MOVE BACK INTO THE AREA
LATE SUNDAY AS THE HIGH BEGINS TO LOSE ITS LOCAL INFLUENCE.
LENNING
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 06Z...
* POTENTIAL FOR FOG OVERNIGHT.
* SW TO W WINDS TONIGHT THROUGH TUESDAY SWITCHING TO NORTHEAST
TUESDAY EVENING.
* POTENTIAL FOR FOG/IFR CIGS BEHIND FRONT TUESDAY EVENING/NIGHT.
BMD
//DISCUSSION...UPDATED 06Z...
A COLD FRONT IS LAID OUT EAST TO WEST BISECTING WISCONSIN LATE THIS
EVENING AND IS PROGGED TO SLOWLY SAG SOUTH ACROSS THE REGION THROUGH
THE FORECAST PERIOD. AHEAD OF THE FRONT TONIGHT THROUGH MID TUESDAY
MORNING...LIGHT SOUTHWEST WINDS WILL PREVAIL. HUMID CONDITIONS MAY
RESULT IN PATCHY FOG OVERNIGHT BUT OVERCAST SKIES WILL LIMIT
RADIATIONAL COOLING. FOR NOW WILL ADD MVFR CONDITIONS TO RFD/DPA BUT
KEEP IT OUT OF THE LESS FOG PRONE CHICAGO TERMINALS AND MONITOR
CONDITIONS OVERNIGHT. INSTABILITY WILL QUICKLY BUILD AS THE SURFACE
HEATS UP DURING THE DAY TUESDAY AND SCATTERED THUNDERSTORMS ARE ONCE
AGAIN EXPECTED TO DEVELOP. THERE MAY BE SOME FOCUS OF THUNDERSTORM
ACTIVITY NEAR AND IMMEDIATELY AHEAD OF THE COLD FRONT...BUT UNCAPPED
CONDITIONS COULD RESULT IN SCATTERED THUNDERSTORMS ANYWHERE ACROSS
NORTHERN ILLINOIS FROM EARLY AFTERNOON ON. WILL FOCUS THE TIMING IN
THE TAF ON THE BETTER CHANCES NEAR FROPA. THE FRONT WILL LIKELY
SURGE DOWN THE LAKE WITH THE HELP OF THE COOLER LAKE WATERS...WITH
AN ENHANCED LAKE BREEZE PUSHING ACROSS THE TERMINALS LATE AFTERNOON
TO EARLY EVENING AND TURNING WINDS NORTHEASTERLY. FOG OVER LAKE
MICHIGAN WILL LIKELY SPILL INLAND BUT IT IS UNCERTAIN HOW FAR...AND
MAY LIFT TO AN IFR OR LOWER MVFR CIG BY THE TIME IT REACHES ORD/MDW.
WILL REMAIN CONSERVATIVE FOR NOW PER MET/MAV GUIDANCE. THUNDERSTORM
CHANCES SHOULD QUICKLY FADE NORTH OF THE FRONT.
BMD
//ORD AND MDW CONFIDENCE...UPDATED 06Z...
* LOW CONFIDENCE IN FOG TONIGHT....AND AGAIN TUESDAY NIGHT ALONG
WITH IFR CIGS.
* HIGH CONFIDENCE IN SCATTERED THUNDERSTORMS...LOW-MEDIUM
CONFIDENCE IN TIMING IMPACTS AT TERMINALS.
BMD
//OUTLOOK FOR ORD/MDW FOR 12Z WEDNESDAY-12Z MONDAY...UPDATED 00Z...
WEDNESDAY THROUGH SUNDAY...GENERALLY VFR. GENERALLY EAST OR
NORTHEAST WINDS THROUGH THE PERIOD.
IZZI
&&
.MARINE...
251 AM CDT
A COLD FRONT CURRENTLY DRAPED ACROSS THE NORTHERN THIRD OF THE LAKE
WILL CONTINUE TO SAG SOUTH THROUGH THE DAY...CLEARING THE SOUTH END
OF THE LAKE THIS EVENING. AHEAD OF THE FRONT...SOUTH TO SOUTHWEST
WINDS HAVE TRANSPORTED MOIST AIR OVER THE COOL STABLE WATERS OF THE
LAKE RESULTING IN DENSE FOG DEVELOPING OVER THE OPEN WATERS. ONCE
WINDS TURN NORTHERLY BEHIND THE FRONT...DRIER AIR WILL GRADUALLY
ERODE THE FOG AND VISIBILITY SHOULD IMPROVE FROM THE NORTH THIS
EVENING AND TONIGHT. SOME OF THIS FOG MAY BE SHUNTED BACK INTO THE
IL/IN NEARSHORE WATERS THIS EVENING AS THE FRONT PUSHES ACROSS. HIGH
PRESSURE BUILDS ACROSS THE GREAT LAKES MIDWEEK AND REMAINS SITUATED
THERE FOR THE REMAINDER OF THE WEEK WITH A PERIOD OF MODEST NORTH TO
NORTHEAST FLOW THROUGH FRIDAY. WINDS MAY BE LIGHT ENOUGH TO TURN A
LAKE BREEZE RESULTING IN ONSHORE FLOW IN THE AFTERNOON AND EVENING
HOURS EACH DAY. WINDS BEGIN TO VEER BACK TOWARDS THE SOUTH SATURDAY
AS LOW PRESSURE DEEPENS OVER THE PLAINS AND LIFTS A WARM FRONT BACK
ACROSS LAKE MICHIGAN THIS WEEKEND.
BMD
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...DENSE FOG ADVISORY...LMZ261-LMZ362-LMZ364-LMZ366-LMZ563-LMZ565-
LMZ567-LMZ868 UNTIL 3 PM TUESDAY.
DENSE FOG ADVISORY...LMZ080-LMZ669-LMZ671-LMZ673-LMZ675-LMZ777-
LMZ779-LMZ870-LMZ872-LMZ874-LMZ876-LMZ878 UNTIL 9 PM
TUESDAY.
&&
$$
VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
WWW.FACEBOOK.COM/US.NATIONALWEATHERSERVICE.CHICAGO.GOV
WWW.TWITTER.COM/NWSCHICAGO
WWW.YOUTUBE.COM/NWSCHICAGO
Area Forecast Discussion
National Weather Service Lincoln IL
217 AM CDT Tue May 27 2014
.DISCUSSION...
ISSUED 215 AM CDT Tue May 27 2014
Weak surface low centered just east of Minneapolis early this
morning, with a boundary extending southwest into north central
Iowa. Earlier showers/storms in southwest Illinois, associated
with a weak trough around 925 mb, have largely faded with just
some sprinkles perhaps in the far southwest CWA west of
Jacksonville. Persistent large upper low evident on water vapor
imagery continues to make slow progress east-southeast, and was
centered over the Texas panhandle, with a broad trough extending
northward through the Plains.
SHORT TERM...Today through Thursday:
Still not much change in the weather pattern during this part of
the forecast. Main concern will be with diurnal showers and
storms. While the upper low will not directly impact us, it still
will have a bit of influence with a shortwave in the northern
stream, which will slip a backdoor cold front through the forecast
area on Wednesday. This front will bring slightly cooler
temperatures by mid week, namely lower 80s vs mid/upper 80s.
Similar to yesterday, scattered showers and thunderstorms are
expected to develop late morning, becoming more numerous in the
afternoon before dying off in the evening. Instability expected to
be rather modest, with the NAM and RAP keeping CAPE`s over most of
the forecast area below 1000 J/kg, so severe weather is of little
concern. However, precipitable water values around 1.6 inches
would favor some heavier downpours, but the scattered nature of
the storms will result in widely varying precipitation amounts.
Somewhat better rain chances expected on Wednesday as the front
arrives and provides some better forcing, and have increased
PoP`s to around 60% across the central third of the CWA. For
Thursday, the evening model runs have started a trend of shifting
the rain chances a bit further south due to the movement of the
front. Have reduced rain chances to around 20% northwest of the
Illinois River as a result, but continued the mention of scattered
storms elsewhere.
LONG TERM...Friday through Monday:
Upper ridge will be drifting through the Mississippi Valley late
in the week, flattening out early next week. Our next rain chances
will be focused on a shortwave that will ride along the top of
what`s left of the ridge late in the weekend. Main rain chances
with this feature look to be Sunday afternoon and evening. The
model solutions then begin to diverge early next week, with the
ECMWF wetter, but its solution has also shifted its rain/frontal
boundary quite a bit further north than the last run. Still looks
to be scattered storms in the general area on Monday with either
this solution or the GFS solution.
Geelhart
&&
.AVIATION...
ISSUED 1155 PM CDT Mon May 26 2014
An area of showers and isolated thunderstorms north of St Louis
will weaken as it drifts NE toward SW TAF sites especially SPI
during overnight. Added VCSH to SPI, PIA and DEC to account for
this but think most areas will stay dry thru Tue morning with just
isolated showers. A light fog possible after 08Z with vsbys 4-6
miles especially at PIA where temp/dew point spread down to 5F
and best chances of reaching crossover temperatures within a
couple hours of sunrise. Isolated to scattered convection to
develop again by mid and late Tue afternoon in unstable air mass
with late afternoon CAPES peaking from 800-1600 j/kg and highest
near southeast airports of CMI and DEC. This convection to
dissipate around sunset so included VCTS after 20Z across the 5
central IL TAFs. SW winds 4-7 kts overnight into early Tue morning
to increase to near 10 kts after 15Z/10 AM Tue and diminish to
around 5 kts after sunset.
07
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS INDIANAPOLIS IN
1018 PM EDT WED MAY 28 2014
.UPDATE...
THE AVIATION SECTION HAS BEEN UPDATED BELOW.
&&
.SYNOPSIS...
ISSUED AT 328 PM EDT WED MAY 28 2014
A WEAK COLD FRONT WILL MOVE THROUGH CENTRAL INDIANA TONIGHT AND
THURSDAY BRINGING SOME SHOWERS AND THUNDERSTORMS WITH IT. FRIDAY AND
SATURDAY WILL BE DRY WITH HIGH PRESSURE IN CONTROL...BUT CHANCES FOR
RAIN RETURN FOR LATE SUNDAY INTO NEXT WEEK AS ANOTHER SYSTEM BEGINS
TO INFLUENCE THE AREA. TEMPERATURES WILL REMAIN WARM THROUGH THE
PERIOD.
&&
.NEAR TERM /OVERNIGHT/...
ISSUED AT 923 PM EDT WED MAY 28 2014
SURFACE ANALYSIS EARLY THIS EVENING SHOWS A SLOWING FRONTAL
BOUNDARY NEAR INTERSTATE 70. RAIN COOLED AIR NORTH OF THE FRONT
HAS RESULTED IN COOLER TEMPS...LOWER DEW POINTS AND MORE STABLE
AIR. SOUTH OF THE FRONT...THE AIR MASS REMAINED UNSTABLE AND SCT
SHRA/TSRA WERE DEVELOPING. HOWEVER...WITH HEATING WANING...ANY
SHOWERS OR STORMS THAT DEVELOP ARE EXPECTED TO WEAKEN QUICKLY
DURING THE NEXT SEVERAL HOURS. HRRR AGREES. AS FOR TEMPS HAVE
TRENDED LOWS A BIT COOLER IN THE RAIN COOLED AIR MASS TO THE
NORTH...AND STUCK WARMER AHEAD OF THE FRONT TO THE SOUTH.
&&
.SHORT TERM /THURSDAY THROUGH SATURDAY/...
ISSUED AT 328 PM EDT WED MAY 28 2014
FOCUS IS ON CHANCES FOR RAIN EARLY IN THE PERIOD. MODELS ARE CLOSE
ENOUGH THAT A BLEND CAN BE USED.
WITH FRONT IN THE AREA ON THURSDAY CONTINUED CHANCE POPS MOST
AREAS...HIGHEST IN THE SOUTH CLOSEST TO THE FRONT. DO NOT SEE ENOUGH
FORCING FOR LIKELY OR HIGHER POPS WITH NO UPPER SUPPORT. TIMING OF
BEST CHANCES WILL BE LATE MORNING INTO AFTERNOON AS INSTABILITY
BUILDS.
AS FRONT CONTINUES ITS SLOW JOURNEY SOUTH KEPT LINGERING SLIGHT
CHANCE TO LOW CHANCE POPS IN THE SOUTHWEST FORECAST AREA THURSDAY
EVENING. FRONT SHOULD BE FAR ENOUGH SOUTH AND INSTABILITY LOW ENOUGH
OVERNIGHT THURSDAY FOR DRY POPS.
ON FRIDAY AND SATURDAY UPPER HIGH WILL BUILD IN AND PROVIDE DRY
CONDITIONS.
GENERALLY TRENDED TOWARD THE MAV MOS THROUGH THE PERIOD AS MET LOOKS
A BIT COOL WITH NO GOOD SHOT OF COOLER AIR MOVING IN.
&&
.LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/...
ISSUED AT 213 PM EDT WED MAY 28 2014
HIGH PRESSURE OVER THE EASTERN U.S. AND AN UPPER RIDGE OF HIGH
PRESSURE MOVING EAST OF OUR AREA WHILE UPPER TROUGHING DEVELOPS OVER
THE WESTERN STATES SPELLS WARM TEMPERATURES AND RETURN OF GULF
MOISTURE AND HIGHER HUMIDITY BY SUNDAY NIGHT. MINOR SHORT WAVES
MOVING THROUGH THE FLOW MEAN TIMING ISSUES FOR PRECIPITATION AND
HARD TO PINPOINT MOST LIKELY WINDOWS OF OPPORTUNITY FOR RAIN. HAVE
THUS CARRIED CHANCE POPS FOR NEARLY ALL PERIODS STARTING SUNDAY
WHICH ACTUALLY TIES TO ALL MODEL SOLUTIONS OF SOME PRECIPITATION
POSSIBLE DAY OR NIGHT INTO MIDWEEK.
AS FOR TEMPERATURES...WITH ABOVE NORMAL HEIGHTS AND INCREASING
DEWPOINTS STARTING SUNDAY EXPECT MAXS AND MINS TO BE ABOVE NORMAL
FOR THIS TIME OF YEAR. NO SIGNIFICANT ADJUSTMENTS TO CURRENT
FORECAST TEMPS WERE MADE...USING A MIX OF MOS DATA AND BLENDED
SETS.
&&
.AVIATION /DISCUSSION FOR 290300Z IND TAF UPDATE/...
ISSUED AT 1018 PM EDT WED MAY 28 2014
ISOLATED THUNDERSTORMS WELL WEST OF THE TERMINAL AND MOVING LITTLE.
SO...AS INSTABILITY CONTINUES TO DIMINISH OWING TO THE LOSS OF SOLAR
HEATING...DO NOT SEE ANY STORM EFFECTING IND.
PREVIOUS DISCUSSION FOLLOWS...
CONFIDENCE IS WANING FOR STORM COVERAGE...ESPECIALLY AT HUF AND
IND...WHERE INSTABILITY HAS NOT BEEN TOO IMPRESSIVE. THAT
SAID...OUTFLOW FROM NORTHERN STORMS MOVING INTO NORTHEASTERN MARION
COUNTY COULD TRIGGER A STORM OR TWO AS THE BOUNDARY DROPS FURTHER
SOUTH. THE ATMOSPHERE IS MORE UNSTABLE ACROSS SOUTH CENTRAL
INDIANA...AND RADAR WAS SHOWING ISOLATED TO SCATTERED THUNDERSTORMS
DEVELOPING AND LIFTING SLOWLY NORTHEAST. WITH ALL THAT SAID...NO
FORCING ALOFT...SO AM NOT CONFIDENT ENOUGH TO HOLD ON TO VCTS ANY
LONGER THAN AN HOUR AFTER SUNSET AKA 02Z.
NEAR SURFACE SHOULD BE A LITTLE MORE MOIST OVERNIGHT THAN LAST
NIGHT..ESPECIALLY IF ANY OF THE TAF SITES GET RAIN. SO...WILL GO
WITH A PERIOD OF MVFR FOR NEAR AND JUST AFTER SUNRISE FROM AROUND
09Z-12Z. COULD ONCE AGAIN SEE SCATTERED STORMS AFTER 16Z TOMORROW
MAINLY AT BMG AND HUF AS THE FRONT SHOULD BE SOUTH OF THE OTHER
TERMINALS.
WINDS WILL BE LIGHT SOUTHWEST AHEAD OF THE FRONT AND OUTFLOW AND
LIGHT NORTHEAST BEHIND IT.
&&
.IND WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...50
NEAR TERM...PUMA
SHORT TERM...50
LONG TERM....TUCEK
AVIATION...MK
VISIT US AT HTTP://WWW.WEATHER.GOV/IND
FOLLOW US ON TWITTER AND YOUTUBE AT:
WWW.TWITTER.COM/NWSINDIANAPOLIS
WWW.YOUTUBE.COM/NWSINDIANAPOLIS
AREA FORECAST DISCUSSION
NWS INDIANAPOLIS IN
944 PM EDT WED MAY 28 2014
.UPDATE...
THE NEAR TERM SECTION HAS BEEN UPDATED BELOW.
&&
.SYNOPSIS...
ISSUED AT 328 PM EDT WED MAY 28 2014
A WEAK COLD FRONT WILL MOVE THROUGH CENTRAL INDIANA TONIGHT AND
THURSDAY BRINGING SOME SHOWERS AND THUNDERSTORMS WITH IT. FRIDAY AND
SATURDAY WILL BE DRY WITH HIGH PRESSURE IN CONTROL...BUT CHANCES FOR
RAIN RETURN FOR LATE SUNDAY INTO NEXT WEEK AS ANOTHER SYSTEM BEGINS
TO INFLUENCE THE AREA. TEMPERATURES WILL REMAIN WARM THROUGH THE
PERIOD.
&&
.NEAR TERM /OVERNIGHT/...
ISSUED AT 923 PM EDT WED MAY 28 2014
SURFACE ANALYSIS EARLY THIS EVENING SHOWS A SLOWING FRONTAL
BOUNDARY NEAR INTERSTATE 70. RAIN COOLED AIR NORTH OF THE FRONT
HAS RESULTED IN COOLER TEMPS...LOWER DEW POINTS AND MORE STABLE
AIR. SOUTH OF THE FRONT...THE AIR MASS REMAINED UNSTABLE AND SCT
SHRA/TSRA WERE DEVELOPING. HOWEVER...WITH HEATING WANING...ANY
SHOWERS OR STORMS THAT DEVELOP ARE EXPECTED TO WEAKEN QUICKLY
DURING THE NEXT SEVERAL HOURS. HRRR AGREES. AS FOR TEMPS HAVE
TRENDED LOWS A BIT COOLER IN THE RAIN COOLED AIR MASS TO THE
NORTH...AND STUCK WARMER AHEAD OF THE FRONT TO THE SOUTH.
&&
.SHORT TERM /THURSDAY THROUGH SATURDAY/...
ISSUED AT 328 PM EDT WED MAY 28 2014
FOCUS IS ON CHANCES FOR RAIN EARLY IN THE PERIOD. MODELS ARE CLOSE
ENOUGH THAT A BLEND CAN BE USED.
WITH FRONT IN THE AREA ON THURSDAY CONTINUED CHANCE POPS MOST
AREAS...HIGHEST IN THE SOUTH CLOSEST TO THE FRONT. DO NOT SEE ENOUGH
FORCING FOR LIKELY OR HIGHER POPS WITH NO UPPER SUPPORT. TIMING OF
BEST CHANCES WILL BE LATE MORNING INTO AFTERNOON AS INSTABILITY
BUILDS.
AS FRONT CONTINUES ITS SLOW JOURNEY SOUTH KEPT LINGERING SLIGHT
CHANCE TO LOW CHANCE POPS IN THE SOUTHWEST FORECAST AREA THURSDAY
EVENING. FRONT SHOULD BE FAR ENOUGH SOUTH AND INSTABILITY LOW ENOUGH
OVERNIGHT THURSDAY FOR DRY POPS.
ON FRIDAY AND SATURDAY UPPER HIGH WILL BUILD IN AND PROVIDE DRY
CONDITIONS.
GENERALLY TRENDED TOWARD THE MAV MOS THROUGH THE PERIOD AS MET LOOKS
A BIT COOL WITH NO GOOD SHOT OF COOLER AIR MOVING IN.
&&
.LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/...
ISSUED AT 213 PM EDT WED MAY 28 2014
HIGH PRESSURE OVER THE EASTERN U.S. AND AN UPPER RIDGE OF HIGH
PRESSURE MOVING EAST OF OUR AREA WHILE UPPER TROUGHING DEVELOPS OVER
THE WESTERN STATES SPELLS WARM TEMPERATURES AND RETURN OF GULF
MOISTURE AND HIGHER HUMIDITY BY SUNDAY NIGHT. MINOR SHORT WAVES
MOVING THROUGH THE FLOW MEAN TIMING ISSUES FOR PRECIPITATION AND
HARD TO PINPOINT MOST LIKELY WINDOWS OF OPPORTUNITY FOR RAIN. HAVE
THUS CARRIED CHANCE POPS FOR NEARLY ALL PERIODS STARTING SUNDAY
WHICH ACTUALLY TIES TO ALL MODEL SOLUTIONS OF SOME PRECIPITATION
POSSIBLE DAY OR NIGHT INTO MIDWEEK.
AS FOR TEMPERATURES...WITH ABOVE NORMAL HEIGHTS AND INCREASING
DEWPOINTS STARTING SUNDAY EXPECT MAXS AND MINS TO BE ABOVE NORMAL
FOR THIS TIME OF YEAR. NO SIGNIFICANT ADJUSTMENTS TO CURRENT
FORECAST TEMPS WERE MADE...USING A MIX OF MOS DATA AND BLENDED
SETS.
&&
.AVIATION /DISCUSSION FOR 290000Z TAF ISSUANCE/...
ISSUED AT 645 PM EDT WED MAY 28 2014
CONFIDENCE IS WANING FOR STORM COVERAGE...ESPECIALLY AT HUF AND
IND...WHERE INSTABILITY HAS NOT BEEN TOO IMPRESSIVE. THAT
SAID...OUTFLOW FROM NORTHERN STORMS MOVING INTO NORTHEASTERN MARION
COUNTY COULD TRIGGER A STORM OR TWO AS THE BOUNDARY DROPS FURTHER
SOUTH. THE ATMOSPHERE IS MORE UNSTABLE ACROSS SOUTH CENTRAL
INDIANA...AND RADAR WAS SHOWING ISOLATED TO SCATTERED THUNDERSTORMS
DEVELOPING AND LIFTING SLOWLY NORTHEAST. WITH ALL THAT SAID...NO
FORCING ALOFT...SO AM NOT CONFIDENT ENOUGH TO HOLD ON TO VCTS ANY
LONGER THAN AN HOUR AFTER SUNSET AKA 02Z.
NEAR SURFACE SHOULD BE A LITTLE MORE MOIST OVERNIGHT THAN LAST
NIGHT..ESPECIALLY IF ANY OF THE TAF SITES GET RAIN. SO...WILL GO
WITH A PERIOD OF MVFR FOR NEAR AND JUST AFTER SUNRISE FROM AROUND
09Z-12Z. COULD ONCE AGAIN SEE SCATTERED STORMS AFTER 16Z TOMORROW
MAINLY AT BMG AND HUF AS THE FRONT SHOULD BE SOUTH OF THE OTHER
TERMINALS.
WINDS WILL BE LIGHT SOUTHWEST AHEAD OF THE FRONT AND OUTFLOW AND
LIGHT NORTHEAST BEHIND IT.
&&
.IND WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...50
NEAR TERM...PUMA
SHORT TERM...50
LONG TERM....TUCEK
AVIATION...MK
VISIT US AT HTTP://WWW.WEATHER.GOV/IND
FOLLOW US ON TWITTER AND YOUTUBE AT:
WWW.TWITTER.COM/NWSINDIANAPOLIS
WWW.YOUTUBE.COM/NWSINDIANAPOLIS
AREA FORECAST DISCUSSION
NWS NORTHERN INDIANA
822 PM EDT WED MAY 28 2014
.SYNOPSIS...
ISSUED AT 516 PM EDT WED MAY 28 2014
A FRONTAL BOUNDARY IS EXPECTED SHIFT SOUTH OUT OF THE AREA
TONIGHT...BRINGING AN END TO SHOWERS AND THUNDERSTORMS. HIGH
PRESSURE WILL THEN BUILD IN FOR THE END OF THE WEEK AND INTO THE
START OF THE WEEKEND. LOWS TONIGHT WILL RANGE FROM THE 50S NORTH
TO LOWER 60S SOUTH WITH HIGHS ON THURSDAY AROUND 80 DEGREES
EXCEPT FOR NEAR LAKE MICHIGAN WHICH WILL BE IN THE 70S.
&&
.SHORT TERM...(THIS EVENING THROUGH THURSDAY)
ISSUED AT 336 PM EDT WED MAY 28 2014
LOOSELY DEFINED "COLD" FRONT...MORE ACCURATELY DESCRIBED AS A WEAK
SURFACE PRESSURE TROUGH WITH A MODEST MOISTURE/DENSITY
GRADIENT...CONTINUES TO SLOWLY PUSH SOUTH ACROSS THE AREA AT PRESS
TIME. AS PREVIOUSLY NOTED...VERY LITTLE SYNOPTIC SUPPORT ALONG THIS
FRONT WITH JUST A VERY WEAK VORTICITY LOBE WINDING DOWN ACROSS THE
REGION. SHOWERS AND THUNDERSTORMS BEING DRIVEN BY SUBTLE CONVERGENCE
ALONG OLD OUTFLOW/DIFFERENTIAL HEATING BOUNDARIES IN A MOIST AND
MARGINALLY UNSTABLE AIRMASS. EARLY DAY INSOLATION ALLOWED FOR A
DECENT RISE IN MLCAPE VALUES ACROSS OUR SOUTHERN COUNTIES WHILE FAR
NORTHERN ZONES REMAIN LARGELY CAPPED AND STABLE. NUMEROUS SHOWERS
AND THUNDERSTORMS HAVE THEREFORE DEVELOPED IN OUR SOUTHERN CWA AS
EXPECTED. LACK OF APPRECIABLE SHEAR AND/OR CLEAR FORCING MECHANISM
WILL CONTINUE TO SUPPORT PULSE/MULTICELLULAR MODE THROUGH THE
EVENING. AN ISOLATED WET MICROBURST MAY BE POSSIBLE ONCE AGAIN BUT
THREAT FOR MORE WIDESPREAD SEVERE WEATHER IS VERY LOW. HEAVY RAIN IS
STILL THE MAIN THREAT WITH HIGH PW VALUES...WEAK FLOW PARALLEL TO
THE FRONT...AND MORE EFFICIENT WARM RAIN PROCESSES. HRRR AND OTHER
HI-RES GUIDANCE HAVE HAD A VERY GOOD HANDLE ON CONVECTION SO FAR
TODAY AND SUGGEST THUNDERSTORMS WILL DISSIPATE AND DRIFT SOUTH BY
AROUND 03Z WITH THE LOSS OF DAYTIME HEATING AND GRADUAL SOUTHWARD
PUSH OF FRONT. DRY CONDITIONS THEN EXPECTED FOR THE REST OF THE
PERIOD AS HIGH AMPLITUDE RIDGE FOLDS INTO THE GREAT LAKES AND
SUPPORTS SURFACE HIGH PRESSURE. A STRAY SHOWER MAY BE POSSIBLE
TOMORROW MORNING IN OUR FAR SOUTHERN COUNTIES BUT CHANCES ARE VERY
LOW. THERMAL PROFILES BEHIND THIS FRONT ARE NOT VERY DIFFERENT FROM
CURRENT VALUES AND EXPECT INCREASING SUN TO SUPPORT ANOTHER DAY OF
HIGHS NEAR 80F. DEWPOINTS WILL BE TOUCH LOWER THOUGH...TAKING THE
HUMIDITY DOWN A NOTCH.
&&
.LONG TERM...(THURSDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 336 PM EDT WED MAY 28 2014
LONG WAVE PATTERN WITH HIGHLY AMPLIFIED RIDGE OVER THE CENTRAL US
WILL START THE LONG TERM PERIOD. TROF ALONG THE NOAM WEST COAST
EJECTS EASTWARD AND WHILE MODELS DIFFER ON THE TIMING AND
EVOLUTION THERE IS ENOUGH CONSENSUS TO SUPPORT A FLATTENING OF THE
RIDGE OVER THE GREAT LAKES REGION TOWARD THE END OF THE LONG TERM
PERIOD.
THE CHALLENGE IS THE SIGNIFICANT DIFFERENCE BETWEEN THE 06Z AND 12Z
GFS RUN. 12Z MODEL IS MORE CLOSELY ALIGNED WITH THE GEM/ECMWF AND
UKMET - THE 06Z AS THE OUTLIER HAD THE LOW EJECTING FROM THE PLAINS
IN WHAT APPEARS TO BE MUCH TO FAST AND TOO FAR SOUTH.
REGARDLESS WITH ABUNDANT LOW LEVEL MOISTURE AND THE AREA WITHIN THE
WARM SECTOR...EXPECT TO SEE CONVECTION DEVELOP AS CURRENTLY FORECAST
AND SHOULD NOT CAUSE A DRAMATIC CHANGE TO CURRENT GRIDDED FORECAST.
AS THE RIDGE FLATTENS AND WESTERLY FLOW INCREASES WOULD EXPECT TO
SEE THE FRONTAL BOUNDARY PUSH SOUTH OF THE AREA DURING THE LATTER
PART OF THE EXTENDED PERIOD...WITH SLIGHT COOLING. TEMPERATURES
SHOULD STILL REMAIN ABOVE NORMAL THROUGH THE PERIOD.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z THURSDAY EVENING)
ISSUED AT 820 PM EDT WED MAY 28 2014
COUPLE CLOUD TO GROUND STRIKES SOUTH OF KFWA NECESSITATES VCTS AS BACK
BUILDING CONTINUES TO ANCHOR STORM FOR AT LEAST NEXT HOUR.
OTHERWISE FOCUS IS SHIFTING TO BR/LOW CEILING POTENTIAL OVERNIGHT
AS MOIST/WELL MIXED BOUNDARY LAYER COOLS. POTENTIAL FOR WIDESPREAD
STRATUS INTO IFR RANGE LATE TONIGHT/NEAR DAYBREAK AND HAVE
TRENDED NORTHERN INDIANA TAFS MORE PESSIMISTICALLY IN THIS REGARD.
RELATIVELY QUICK BURNOFF/LIFTING CONDENSATION LEVELS TO BRING
RETURN TO VFR MET CONDITIONS BY LATE MORNING THROUGH REMAINDER OF
FORECAST PERIOD.
&&
.IWX WATCHES/WARNINGS/ADVISORIES...
IN...NONE.
MI...NONE.
OH...NONE.
LM...NONE.
&&
$$
SYNOPSIS...CEO
SHORT TERM...AGD
LONG TERM...LEWIS
AVIATION...MURPHY
VISIT US AT WWW.WEATHER.GOV/IWX (ALL LOWER CASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
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WWW.TWITTER.COM/NWSIWX
WWW.YOUTUBE.COM/NWSNORTHERNINDIANA
AREA FORECAST DISCUSSION
NWS NORTHERN INDIANA
143 AM EDT TUE MAY 27 2014
.SYNOPSIS...
ISSUED AT 755 PM EDT MON MAY 26 2014
HIGH PRESSURE WILL CONTINUE TO SHIFT EAST AHEAD OF AN APPROACHING
UPPER LEVEL DISTURBANCE AND SURFACE COLD FRONT. INCREASING CLOUDS
AND CHANCES FOR SHOWERS AND THUNDERSTORMS WILL BE IN STORE...
ESPECIALLY FOR TUESDAY AFTERNOON. LOW TEMPERATURES WILL ONLY DROP
INTO THE MID AND UPPER 60S TONIGHT WITH HIGHS IN THE LOWER TO MID
80S AGAIN ON TUESDAY.
&&
.SHORT TERM...(THIS EVENING THROUGH TUESDAY)
ISSUED AT 335 PM EDT MON MAY 26 2014
OHIO VALLEY REMAINS LARGELY UNDER THE INFLUENCE OF EXPANSIVE
RIDGING ALOFT AHEAD OF SOUTHERN PLAINS CUTOFF LOW. DESPITE THIS
FACT...A WEAK COLD FRONT EXTENDING FROM A SURFACE LOW OVER QUEBEC
WILL GRADUALLY SETTLE SOUTH ACROSS THE GREAT LAKES TONIGHT AND
TOMORROW. MIDLEVEL HEIGHT FALLS/CVA ARE DISPLACED WELL TO THE
NORTHEAST BUT STABLE LAKE AGGREGATE WILL HELP NUDGE THIS COLD
FRONT SOUTH. MEANWHILE...A VERY HIGH THETA-E AIRMASS IS BEING
ADVECTED INTO THE REGION FROM THE SOUTHERN PLAINS AND WESTERN
GULF. A COMPARISON OF THE 12Z KILX AND KDTX SOUNDINGS ILLUSTRATES
THIS ONGOING MOISTURE SURGE. LOCAL PW VALUES ARE EXPECTED TO
APPROACH OR EXCEED 1.75 INCHES BY LATER TONIGHT AND PERSIST
THROUGH TOMORROW. AFTER A SLOW START THIS MORNING...SURFACE
DEWPOINTS HAVE FINALLY SURGED INTO THE LOW/MID 60S ACROSS OUR
AREA. LATEST SPC/RAP MESOANALYSIS INDICATES AROUND 1000 J/KG OF
MLCAPE FINALLY NOSING INTO OUR CWA DESPITE PALTRY MIDLEVEL LAPSE
RATES. THE PROBLEM HERE REMAINS A LACK OF ANY SYNOPTIC
SUPPORT/TRIGGERING MECHANISM. CONVERGENT BOUNDARY REMAINS WELL TO
OUR NORTH WITH RIDGE AXIS FIRMLY IN PLACE OVER OUR AREA.
THUNDERSTORM CHANCES THROUGH THE EVENING WILL DEPEND ON FINER
SCALE DETAILS SUCH AS POTENTIAL OUTFLOW BOUNDARIES FROM UPSTREAM
CONVECTION. LATEST HRRR GENERATES SOME VERY ISOLATED CONVECTION IN
OUR WESTERN COUNTIES AROUND 22Z BUT SUGGESTS THE BEST POTENTIAL
FOR RAIN WILL BE AFTER 00Z WHEN WHATEVER IS LEFT OF CONVECTION
OVER WESTERN ILLINOIS FINALLY WASHES INTO OUR CWA. WITH THE LOSS
OF DAYTIME HEATING THIS ACTIVITY WILL LIKELY BE WEAKENING
SUBSTANTIALLY BY THE TIME IT REACHES US THOUGH. WILL MAINTAIN
LOWER END CHANCE POPS WITH THE HIGHEST VALUES IN OUR WESTERN
COUNTIES. IN VERY SUMMER-LIKE FASHION...EXPECT "POPCORN"
THUNDERSTORMS WITH VERY LOW SEVERE RISK GIVEN LIGHT WINDS
ALOFT/LIMITED SHEAR. BRIEF HEAVY RAIN WILL PROBABLY BE THE BIGGEST
THREAT WITH SLOW STORM MOTION...HIGH MOISTURE CONTENT...AND DEEP
WARM CLOUD LAYER.
SUBTLE HEIGHT FALLS/VORTICITY MAXIMA WILL THEN APPROACH THE REGION
LATE TONIGHT. DIURNAL STABILIZATION WILL PREVENT ANY SURFACE BASED
CONVECTION BUT FORECAST SOUNDINGS INDICATE ENOUGH ELEVATED
INSTABILITY TO SUPPORT A FEW LINGERING SHOWERS/THUNDERSTORMS THROUGH
THE MORNING HOURS. COVERAGE EXPECTED TO BE LOW HOWEVER. MUCH BETTER
CHANCES FOR RAIN/STORMS WILL ARRIVE TOMORROW AFTERNOON AS FRONTAL
BOUNDARY APPROACHES AND TAKES ADVANTAGE OF VERY MOIST AND MARGINALLY
UNSTABLE AIRMASS IN PLACE. EXPECT HIGH SURFACE DEWPOINTS AND LITTLE
TO NO CAPPING INVERSION TO SUPPORT NUMEROUS PULSE STORMS FROM LATE
MORNING THROUGH THE EVENING. MLCAPE VALUES ARE LOW...GENERALLY 1000
J/KG OR LESS...AND THERE IS VIRTUALLY NO SHEAR TO HELP ORGANIZE ANY
SIGNIFICANT UPDRAFTS THAT DO MANAGE TO DEVELOP. SEVERE WEATHER RISK
IS THEREFORE LOW BUT ONCE AGAIN LOCALIZED HEAVY RAIN WILL BE
POSSIBLE...ESPECIALLY GIVEN INCREASED POTENTIAL FOR BACK-BUILDING
AND TRAINING STORMS.
&&
.LONG TERM...(TUESDAY NIGHT THROUGH MONDAY)
ISSUED AT 335 PM EDT MON MAY 26 2014
SHRTWV OVER ONTARIO MOVG THROUGH TOP OF WRN GRTLKS RIDGE THIS AFTN
EXPECTED TO DROP SEWD TO THE ERN GRTLKS BY TUE EVE. ASSOCIATED SFC
CDFNT TRAILING WSW THROUGH MN WILL BECOME MORE E-W ORIENTED BY THE
TIME IT REACHES OUR CWA TUE NGT... THEN MOVE SLOWLY SOUTH ACROSS OUR
AREA THROUGH WED NGT. SCT MAINLY AFTN/EVE CONVECTION EXPECTED IN THE
VCNTY OF THE FRONT AS IT MOVES THROUGH. INITIALLY WK DRY AIR PUSH
BEHIND THE FRONT SO SOME DIURNALLY DRIVEN LAKE BREEZE CONVECTION
PSBL EVEN AFTER THE FRONT MOVES TO CENTRAL IN/OH. VERY WK FLOW/MOIST
AIRMASS AND EFFICIENT RAINFALL PROCESSES SUGGEST SOME LOCALLY HEAVY
RAINFALL PSBL AS THE FRONT MOVES THROUGH WED AFTN/EVE WHEN
INSTABILITY MAXIMIZED.
FOR THE EXTENDED FCST... RIDGING EXPECTED TO STRENGTHEN OVER CENTRAL
CONUS/CANADA AGAIN THU-FRI AS WEST COAST TROF DEEPENS. RIDGE
EXPECTED TO MOVE EAST ACROSS THE GRTLKS OVER THE WEEKEND AS A RATHER
STRONG SHRTWV LIFTS NE OUT OF THE WRN TROF. MEDIUM RANGE MODELS HAVE
SGFNT DIFFERENCES ON TIMING OF THIS SYSTEM... BUT STILL APPEARS IT
MAY IMPACT THE AREA WITH TSTMS AND A FROPA IN THE SUNDAY-MONDAY
TIMEFRAME. TEMPS SHOULD WARM WELL ABOVE NORMAL AGAIN OVER THE
WEEKEND AS THE UPR RIDGE MOVES OVERHEAD AND SOUTHERLY SFC WINDS
DEVELOP ON BACKSIDE OF SFC RIDGE... WITH FROPA LOWERING TEMPS BACK
CLOSE TO NORMAL EARLY NEXT WEEK.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT)
ISSUED AT 136 AM EDT TUE MAY 27 2014
MOIST AND UNSTABLE AIR WAS HELPING MAINTAIN SHOWERS ACROSS THE
REGION EARLY THIS MORNING DESPITE LACK OF A STRONG FORCING
MECHANISM AND STABILIZED LOWER LEVELS. RADAR MOSAIC INDICATES KSBN
COULD SEE SOME LIGHT SHOWERS FOR A FEW HOURS BEFORE ENDING. CIGS
AND VIS LOOK TO REMAIN VFR WITH THESE SHOWERS BUT WITH LIGHT WINDS
AND MOIST BOUNDARY LAYER CONCERNED THAT ANY BREAKS IN CLOUD COVER
TOWARD DAYBREAK WILL YIELD MVFR BR. SHOWERS HAVE ENDED AT KFWA
WITH OUTFLOW MOVING AWAY AND WINDS WILL QUICKLY RETURN TO LIGHT
AND VARIABLE AS BUBBLE HIGH MOVES IN. SIMILAR CONCERNS WITH MVFR
BR HERE AS WELL. WEAK FRONT WILL SAG INTO THE AREA EARLY TUE
EVENING. MODEST INSTABILITY TODAY AND WITH NUMEROUS REMNANT
OUTFLOW BOUNDARIES COULD SEE SHOWER OR TSRA AT ABOUT ANY TIME
TODAY. CONFINED VCTS MENTION TO AFTERNOON AND EVENING WITH BEST
INSTABILITY AND APPROACH OF FRONT.
&&
.IWX WATCHES/WARNINGS/ADVISORIES...
IN...NONE.
MI...NONE.
OH...NONE.
LM...NONE.
&&
$$
SYNOPSIS...MURPHY
SHORT TERM...AGD
LONG TERM...JT
AVIATION...LASHLEY
VISIT US AT WWW.WEATHER.GOV/IWX (ALL LOWER CASE)
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AREA FORECAST DISCUSSION
NWS QUAD CITIES IA IL
704 PM CDT WED MAY 28 2014
.SYNOPSIS...
ISSUED AT 310 PM CDT WED MAY 28 2014
12Z UA ANALYSIS HAS A WEAK UPPER LOW IN NORTHEAST IOWA WITH A
STRONGER UPPER LOW IN SOUTHWEST ARKANSAS. SEVERAL WEAK DISTURBANCES
WERE ROTATING AROUND THE LOWS. SATELLITE/RADAR TRENDS THROUGH MID
AFTERNOON SHOW DIURNAL CONVECTION ACROSS EASTERN IOWA AND NORTHERN
ILLINOIS THAT WAS SLOWLY ROTATING AROUND THE UPPER LOW IN EASTERN
IOWA.
18Z SFC ANALYSIS HAS AS WEAK LOW NEAR KAWG WITH A BOUNDARY EASTWARD
THROUGH CENTRAL ILLINOIS. DEW POINTS WERE IN THE 60S FROM THE GULF
COAST INTO THE MID MISSISSIPPI AND OHIO VALLEYS. DEW POINTS IN THE
40S AND 50S WERE ACROSS THE GREAT LAKES.
&&
.SHORT TERM...(THIS EVENING THROUGH THURSDAY)
ISSUED AT 310 PM CDT WED MAY 28 2014
RECENT RAP TRENDS INDICATE THE EFFECTIVE BOUNDARY WILL REMAIN NEARLY
STATIONARY FROM ABOUT KAWG TO NEAR KPNT THROUGH LATE AFTERNOON. WITH
THE WEAK UPPER LOW JUST WEST OF THE QUAD CITIES...CONVECTION WILL
DRIFT SLOWLY SOUTH WEST OF THE MISSISSIPPI AND SLOWLY NORTH EAST OF
THE MISSISSIPPI.
DUE TO THE SLOW MOVEMENT OF STORMS...LOCALLY HEAVY RAINFALL WILL BE
SEEN.
BY EARLY EVENING AND CONTINUING THROUGH SUNSET CONVECTION WILL
SLOWLY DISSIPATE WITH CONVECTION BECOMING VERY ISOLATED BY MIDNIGHT.
DURING THE EVENING THE BOUNDARY WILL SLOWLY DRIFT SOUTH AND WILL BE
THE FOCUS FOR MAINTAINING ISOLATED CONVECTION PAST SUNSET.
AFTER MIDNIGHT MOST OF THE AREA IS EXPECTED TO REMAIN DRY AS THE
BOUNDARY CONTINUES A SLOW DRIFT TO THE SOUTH. ANY REMAINING RAIN
WILL BE CONFINED TO AREAS CLOSE TO THE FRONT.
THURSDAY MORNING THERE MAY BE SOME LINGERING SHOWERS ACROSS THE FAR
SOUTH CLOSE TO THE BOUNDARY WHILE THE REMAINDER OF THE AREA IS DRY.
NEW DIURNAL CONVECTION IS EXPECTED TO DEVELOP BY LATE MORNING AND
CONTINUE THROUGH THURSDAY AFTERNOON SOUTH OF I-80. THIS NEW
CONVECTION IS EXPECTED TO BE ISOLATED IN NATURE BUT MAY BE MORE
SCATTERED BETWEEN KBRL AND KUIN.
.LONG TERM...(THURSDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 310 PM CDT WED MAY 28 2014
SURFACE AND UPPER RIDGING WILL MOVE THROUGH THE REGION LATE THIS
WEEK KEEPING DRY WEATHER OVER THE AREA. THUNDERSTORM CHANCES WILL
RETURN TO THE FORECAST OVER THE WEEKEND AND EARLY NEXT WEEK AS LOW
LEVEL MOISTURE INCREASES BEHIND THE DEPARTING RIDGE. THE BEST CHANCE
OF THUNDERSTORMS WILL BE TUESDAY INTO WEDNESDAY AS A COLD FRONT MOVES
SLOWLY THROUGH THE REGION.
THURSDAY NIGHT INTO FRIDAY NIGHT LESS HUMID CONDITIONS WILL BE IN PLACE
WITH A SURFACE HIGH OVER THE WESTERN GREAT LAKES FEEDING DRY AIR
INTO THE REGION. TEMPERATURES SHOULD BE SEASONAL WITH HIGHS FRIDAY
IN THE LOW 80S AND LOWS THURSDAY AND FRIDAY MORNINGS IN THE MID 50S
TO MID 60S.
THUNDERSTORM CHANCES CREEP BACK INTO THE FORECAST FOR THE WEEKEND AS
THE UPPER AND SURFACE RIDING MOVE EAST ALLOWING MOIST RETURN FLOW
TO SET UP. FOR NOW WITHOUT ANY OBVIOUS FORCING MECHANISMS SHOWN IN
THE MODEL SOLUTIONS KEPT POPS IN THE LOW CHANCE CATEGORY.
MODEL SOLUTIONS SHOW A BETTER THREAT OF THUNDERSTORMS EARLY NEXT
WEEK WITH A PERSISTENT SOUTHWEST TROF IN PLACE AND A SERIES OF S/WS
EJECTING OUT OF THE TROF INTO THE PLAINS AND UPPER MIDWEST. THIS
WILL SEND A SLOW MOVING COLD FRONT THROUGH THE REGION TUESDAY INTO
WEDNESDAY. THE GFS/ECMWF GENERALLY AGREE ON THE OVER ALL SYNOPTIC
PATTERN EARLY NEXT WEEK BUT HAVE DIFFERENT TAKES ON HANDLING THE
S/WS IN THE SOUTHWEST FLOW AND THE SURFACE FRONT. THE GFS BRINGS
OUT A MAIN S/W MONDAY NIGHT AND TUESDAY WHICH PUSHES THE COLD FRONT
SOUTHEAST OF THE FORECAST AREA BY WEDNESDAY. THE ECMWF IS MORE
FRAGMENTED WITH THE S/WS AND STALLS THE FRONT OVER OR JUST SOUTH OF
THE CWA BY LATE TUESDAY. EITHER SOLUTION THOUGH SUPPORTS AN ACTIVE
PATTERN.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z THURSDAY EVENING)
ISSUED AT 644 PM CDT WED MAY 28 2014
SHOWERS AND A FEW STORMS MORE PREVALENT EAST OF THE MISSISSIPPI WITHIN
LOW LEVEL MOISTURE CONVERGENCE AHEAD OF LAKE ENHANCED FRONT. ALL
SHOWER/STORM ACTIVITY EXPECTED TO DISSIPATE AFTER SUNSET DUE TO
LOSS OF HEATING. STILL AN ISOLD SHOWER NOT OUT OF QUESTION
OVERNIGHT AND THURSDAY MOSTLY SOUTH OF THE TERMINALS ALONG FRONT.
GENERALLY VFR CONDITIONS EXPECTED INTO THE OVERNIGHT. MODEL GUIDANCE
SUGGESTS MVFR TO IFR CONDITIONS IN LOW CLOUDS AND FOG DEVELOPING
OVERNIGHT IN EASTERLY FLOW. CONFIDENCE OVERALL IS LOW GIVEN LACK
OF LOW CIGS PER SATELLITE TRENDS AND OBS...AND MAY HAVE BETTER CHC
OF MVFR TO IFR CONDITIONS MET DUE TO VSBY RESTRICTIONS BUT LOW
CONFIDENCE ALSO WITH E/NE WINDS BRINGING IN DRIER AIR. HAVE BACKED OFF
ON LOW CIGS BUT MAINTAINED GENERAL MVFR VSBYS AT THE TERMINALS
OVERNIGHT AND EARLY THURSDAY MORNING FOR NOW.
&&
.DVN WATCHES/WARNINGS/ADVISORIES...
IA...NONE.
IL...NONE.
MO...NONE.
&&
$$
SYNOPSIS...08
SHORT TERM...08
LONG TERM...DLF
AVIATION...05
AREA FORECAST DISCUSSION
NWS GOODLAND KS
500 PM MDT TUE MAY 27 2014
.SHORT TERM...(THIS EVENING THROUGH WEDNESDAY)
ISSUED AT 1244 PM MDT TUE MAY 27 2014
MOSTLY SUNNY SKIES...WITH A CUMULUS FIELD DEVELOPING...EXIST OVER
THE CWA THIS AFTERNOON. AN UPPER LOW IS CURRENTLY CIRCULATING OVER
THE SOUTH CENTRAL PLAINS WITH UPPER LEVEL RIDGING MOVING INTO THE
HIGH PLAINS. ENERGY FROM A SHORTWAVE TROUGH OVER THE MIDWEST IS
ROTATING THROUGH EASTERN NEBRASKA. THE REMAINDER OF THE AFTERNOON
SHOULD REMAIN DRY...EVEN THOUGH THE HRRR AND THE PREVIOUS NAM
DEVELOPED SHOWERS OVER RED WILLOW COUNTY NEBRASKA AND NORTON
COUNTY KANSAS LATER THIS AFTERNOON. SINCE THE SHORTWAVE ENERGY
APPEARS TO NOT STRETCH THIS FAR WEST...AND CONSIDERING THE HRRR
HAS NOT BEEN CONSISTENT FROM RUN TO RUN AND THE 12Z NAM REMOVED
PRECIP FROM THE CWA...DECIDED TO GO WITH A DRY FORECAST FOR THIS
AFTERNOON. WINDS WILL BE OUT OF THE EAST NORTHEAST...SHIFTING TO
THE SOUTHEAST OVERNIGHT TO THE SOUTHWEST BY MORNING...AND WILL
REMAIN LIGHT. SCATTERED TO BROKEN CUMULUS THAT DEVELOPS THIS
AFTERNOON WILL DECREASE AFTER SUNSET AS INSTABILITY
DIMINISHES...LEAVING MOSTLY CLEAR SKIES TONIGHT INTO TOMORROW
MORNING.
MOSTLY DRY AND WARM CONDITIONS WILL PERSIST OVER THE CWA TOMORROW.
INCREASED TEMPERATURES SLIGHTLY INTO THE UPPER 80S TO LOW 90S AS
THE RIDGE MOVES OVERHEAD AND 850MB TEMPS RISE INTO THE 20C TO 25C
RANGE. BY AFTERNOON...WINDS WILL SHIFT TO THE EAST SOUTHEAST AT
10 TO 15 MPH...WHICH WILL PROVIDE UPSLOPE FLOW. UPSLOPE FLOW
COMBINED WITH TEMPERATURES HEATING UP COULD PRODUCE THUNDERSTORMS
ALONG THE HIGHER TERRAIN IN COLORADO THAT COULD MOVE EAST INTO FAR
EASTERN COLORADO. SOME OF THE MODELS WERE PICKING UP ON THIS...SO
WENT WITH A SLIGHT CHANCE OF SHOWERS AND ISOLATED THUNDERSTORMS
TOMORROW AFTERNOON...AROUND 21Z TO 23Z...FOR PORTIONS OF EASTERN
COLORADO. CAPE IS UNDER 100O J/KG...SO THUNDERSTORMS THAT DEVELOP
WILL BE ISOLATED AND MAY NOT HAVE ENOUGH STRENGTH TO MAKE IT INTO
THE CWA BUT KEPT IT AT SLIGHT CHANCE FOR ANY THAT MAY MAKE INTO
THE CWA. MOST LOCATIONS SHOULD REMAIN DRY TOMORROW WITH A FEW
CLOUDS AND MOSTLY SUNNY SKIES.
.LONG TERM...(WEDNESDAY NIGHT THROUGH TUESDAY)
ISSUED AT 152 PM MDT TUE MAY 27 2014
UPPER RIDGING WILL RESULT IN DRY AND WARM CONDITIONS THROUGH
THURSDAY. UPSLOPE FLOW INTO THE HIGHER TERRAIN THURSDAY AFTERNOON
WILL INITIATE CONVECTION NEAR THE FRONT RANGE...WHICH MIGHT MAKE
IT INTO NORTHEAST COLORADO BEFORE DISSIPATING THURSDAY EVENING.
THAT PATTERN REPEATS ON FRIDAY...BUT WITH THE UPPER RIDGE MOVING
FURTHER EAST THERE IS A BETTER CHANCE THAT THE COLORADO CONVECTION
WILL MAKE IT INTO THE WESTERN HALF OF THE LOCAL FORECAST AREA
FRIDAY EVENING. ON SATURDAY...WEAK SHORTWAVE EMBEDDED IN THE
SOUTHWEST FLOW AND LEE TROUGH AT THE SURFACE WILL COMBINE TO
INITIATE CONVECTION FURTHER EAST WITH SCATTERED STORMS THROUGH
SATURDAY NIGHT. BEST CHANCES FOR THUNDERSTORMS IN THE PERIOD
APPEAR TO BE ON SUNDAY WITH STRONGER AND BETTER DEFINED UPPER
SHORTWAVE. SLIGHT TO LOW CHANCES FOR THUNDERSTORMS WILL CONTINUE
EARLY NEXT WEEK...BUT MAIN FORCING WILL BE NORTH OF THE AREA AND
PATTERN SUGGESTS A RATHER ROBUST DRY SLOT FURTHER SOUTH WHICH MAY
INHIBIT CHANCES HERE. TEMPERATURES WILL BE SLIGHTLY ABOVE NORMAL
THROUGH THE ENTIRE PERIOD.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z WEDNESDAY EVENING)
ISSUED AT 500 PM MDT TUE MAY 27 2014
KGLD AND KMCK...VFR CONDITIONS THROUGH THE PERIOD. LIGHT/VARIABLE
WINDS UNDER 8KTS EXPECTED AT BOTH TERMINALS THROUGH 16Z THEN
BECOMING SOUTHEASTERLY AROUND 10KTS FROM 17Z THROUGH THE REST OF
THE TAF.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
SHORT TERM...ALW
LONG TERM...024
AVIATION...99
AREA FORECAST DISCUSSION
NWS GOODLAND KS
205 PM MDT TUE MAY 27 2014
.SHORT TERM...(THIS EVENING THROUGH WEDNESDAY)
ISSUED AT 1244 PM MDT TUE MAY 27 2014
MOSTLY SUNNY SKIES...WITH A CUMULUS FIELD DEVELOPING...EXIST OVER
THE CWA THIS AFTERNOON. AN UPPER LOW IS CURRENTLY CIRCULATING OVER
THE SOUTH CENTRAL PLAINS WITH UPPER LEVEL RIDGING MOVING INTO THE
HIGH PLAINS. ENERGY FROM A SHORTWAVE TROUGH OVER THE MIDWEST IS
ROTATING THROUGH EASTERN NEBRASKA. THE REMAINDER OF THE AFTERNOON
SHOULD REMAIN DRY...EVEN THOUGH THE HRRR AND THE PREVIOUS NAM
DEVELOPED SHOWERS OVER RED WILLOW COUNTY NEBRASKA AND NORTON
COUNTY KANSAS LATER THIS AFTERNOON. SINCE THE SHORTWAVE ENERGY
APPEARS TO NOT STRETCH THIS FAR WEST...AND CONSIDERING THE HRRR
HAS NOT BEEN CONSISTENT FROM RUN TO RUN AND THE 12Z NAM REMOVED
PRECIP FROM THE CWA...DECIDED TO GO WITH A DRY FORECAST FOR THIS
AFTERNOON. WINDS WILL BE OUT OF THE EAST NORTHEAST...SHIFTING TO
THE SOUTHEAST OVERNIGHT TO THE SOUTHWEST BY MORNING...AND WILL
REMAIN LIGHT. SCATTERED TO BROKEN CUMULUS THAT DEVELOPS THIS
AFTERNOON WILL DECREASE AFTER SUNSET AS INSTABILITY
DIMINISHES...LEAVING MOSTLY CLEAR SKIES TONIGHT INTO TOMORROW
MORNING.
MOSTLY DRY AND WARM CONDITIONS WILL PERSIST OVER THE CWA TOMORROW.
INCREASED TEMPERATURES SLIGHTLY INTO THE UPPER 80S TO LOW 90S AS
THE RIDGE MOVES OVERHEAD AND 850MB TEMPS RISE INTO THE 20C TO 25C
RANGE. BY AFTERNOON...WINDS WILL SHIFT TO THE EAST SOUTHEAST AT
10 TO 15 MPH...WHICH WILL PROVIDE UPSLOPE FLOW. UPSLOPE FLOW
COMBINED WITH TEMPERATURES HEATING UP COULD PRODUCE THUNDERSTORMS
ALONG THE HIGHER TERRAIN IN COLORADO THAT COULD MOVE EAST INTO FAR
EASTERN COLORADO. SOME OF THE MODELS WERE PICKING UP ON THIS...SO
WENT WITH A SLIGHT CHANCE OF SHOWERS AND ISOLATED THUNDERSTORMS
TOMORROW AFTERNOON...AROUND 21Z TO 23Z...FOR PORTIONS OF EASTERN
COLORADO. CAPE IS UNDER 100O J/KG...SO THUNDERSTORMS THAT DEVELOP
WILL BE ISOLATED AND MAY NOT HAVE ENOUGH STRENGTH TO MAKE IT INTO
THE CWA BUT KEPT IT AT SLIGHT CHANCE FOR ANY THAT MAY MAKE INTO
THE CWA. MOST LOCATIONS SHOULD REMAIN DRY TOMORROW WITH A FEW
CLOUDS AND MOSTLY SUNNY SKIES.
.LONG TERM...(WEDNESDAY NIGHT THROUGH TUESDAY)
ISSUED AT 152 PM MDT TUE MAY 27 2014
UPPER RIDGING WILL RESULT IN DRY AND WARM CONDITIONS THROUGH
THURSDAY. UPSLOPE FLOW INTO THE HIGHER TERRAIN THURSDAY AFTERNOON
WILL INITIATE CONVECTION NEAR THE FRONT RANGE...WHICH MIGHT MAKE
IT INTO NORTHEAST COLORADO BEFORE DISSIPATING THURSDAY EVENING.
THAT PATTERN REPEATS ON FRIDAY...BUT WITH THE UPPER RIDGE MOVING
FURTHER EAST THERE IS A BETTER CHANCE THAT THE COLORADO CONVECTION
WILL MAKE IT INTO THE WESTERN HALF OF THE LOCAL FORECAST AREA
FRIDAY EVENING. ON SATURDAY...WEAK SHORTWAVE EMBEDDED IN THE
SOUTHWEST FLOW AND LEE TROUGH AT THE SURFACE WILL COMBINE TO
INITIATE CONVECTION FURTHER EAST WITH SCATTERED STORMS THROUGH
SATURDAY NIGHT. BEST CHANCES FOR THUNDERSTORMS IN THE PERIOD
APPEAR TO BE ON SUNDAY WITH STRONGER AND BETTER DEFINED UPPER
SHORTWAVE. SLIGHT TO LOW CHANCES FOR THUNDERSTORMS WILL CONTINUE
EARLY NEXT WEEK...BUT MAIN FORCING WILL BE NORTH OF THE AREA AND
PATTERN SUGGESTS A RATHER ROBUST DRY SLOT FURTHER SOUTH WHICH MAY
INHIBIT CHANCES HERE. TEMPERATURES WILL BE SLIGHTLY ABOVE NORMAL
THROUGH THE ENTIRE PERIOD.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON)
ISSUED AT 1114 AM MDT TUE MAY 27 2014
VFR CONDITIONS WILL PREVAIL THROUGH THE TAF PERIOD AS AN UPPER
LEVEL RIDGE OF HIGH PRESSURE MOVES OVER THE HIGH PLAINS. A VERY
WEAK SHORTWAVE TROUGH COULD CLIP THE NORTHEAST EDGE OF THE CWA THIS
AFTERNOON...BUT WAS NOT CONFIDENT ENOUGH IN PRECIP RESULTING FROM
IT AT KMCK. THEREFORE...WENT WITH INCREASING CLOUDS THIS AFTERNOON
WHICH ARE ALREADY APPARENT ON SATELLITE AND FROM THE OFFICE.
INCLUDED A SCATTERED CUMULUS FIELD AT KGLD AND A BROKEN CUMULUS
FIELD AT KMCK FROM 20Z/21Z TO 02Z TONIGHT. WINDS WILL REMAIN ON
THE LIGHT SIDE THIS AFTERNOON INTO TOMORROW MORNING. WINDS WILL
INITIALLY BE FROM THE EAST NORTHEAST BETWEEN 5 TO 10 KTS SHIFTING
TO THE EAST SOUTHEAST THIS EVENING AND THEN TO THE SOUTHWEST BY
MORNING.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
SHORT TERM...ALW
LONG TERM...024
AVIATION...ALW
AREA FORECAST DISCUSSION
NWS GOODLAND KS
108 PM MDT TUE MAY 27 2014
.SHORT TERM...(THIS EVENING THROUGH WEDNESDAY)
ISSUED AT 1244 PM MDT TUE MAY 27 2014
MOSTLY SUNNY SKIES...WITH A CUMULUS FIELD DEVELOPING...EXIST OVER
THE CWA THIS AFTERNOON. AN UPPER LOW IS CURRENTLY CIRCULATING OVER
THE SOUTH CENTRAL PLAINS WITH UPPER LEVEL RIDGING MOVING INTO THE
HIGH PLAINS. ENERGY FROM A SHORTWAVE TROUGH OVER THE MIDWEST IS
ROTATING THROUGH EASTERN NEBRASKA. THE REMAINDER OF THE AFTERNOON
SHOULD REMAIN DRY...EVEN THOUGH THE HRRR AND THE PREVIOUS NAM
DEVELOPED SHOWERS OVER RED WILLOW COUNTY NEBRASKA AND NORTON
COUNTY KANSAS LATER THIS AFTERNOON. SINCE THE SHORTWAVE ENERGY
APPEARS TO NOT STRETCH THIS FAR WEST...AND CONSIDERING THE HRRR
HAS NOT BEEN CONSISTENT FROM RUN TO RUN AND THE 12Z NAM REMOVED
PRECIP FROM THE CWA...DECIDED TO GO WITH A DRY FORECAST FOR THIS
AFTERNOON. WINDS WILL BE OUT OF THE EAST NORTHEAST...SHIFTING TO
THE SOUTHEAST OVERNIGHT TO THE SOUTHWEST BY MORNING...AND WILL
REMAIN LIGHT. SCATTERED TO BROKEN CUMULUS THAT DEVELOPS THIS
AFTERNOON WILL DECREASE AFTER SUNSET AS INSTABILITY
DIMINISHES...LEAVING MOSTLY CLEAR SKIES TONIGHT INTO TOMORROW
MORNING.
MOSTLY DRY AND WARM CONDITIONS WILL PERSIST OVER THE CWA TOMORROW.
INCREASED TEMPERATURES SLIGHTLY INTO THE UPPER 80S TO LOW 90S AS
THE RIDGE MOVES OVERHEAD AND 850MB TEMPS RISE INTO THE 20C TO 25C
RANGE. BY AFTERNOON...WINDS WILL SHIFT TO THE EAST SOUTHEAST AT
10 TO 15 MPH...WHICH WILL PROVIDE UPSLOPE FLOW. UPSLOPE FLOW
COMBINED WITH TEMPERATURES HEATING UP COULD PRODUCE THUNDERSTORMS
ALONG THE HIGHER TERRAIN IN COLORADO THAT COULD MOVE EAST INTO FAR
EASTERN COLORADO. SOME OF THE MODELS WERE PICKING UP ON THIS...SO
WENT WITH A SLIGHT CHANCE OF SHOWERS AND ISOLATED THUNDERSTORMS
TOMORROW AFTERNOON...AROUND 21Z TO 23Z...FOR PORTIONS OF EASTERN
COLORADO. CAPE IS UNDER 100O J/KG...SO THUNDERSTORMS THAT DEVELOP
WILL BE ISOLATED AND MAY NOT HAVE ENOUGH STRENGTH TO MAKE IT INTO
THE CWA BUT KEPT IT AT SLIGHT CHANCE FOR ANY THAT MAY MAKE INTO
THE CWA. MOST LOCATIONS SHOULD REMAIN DRY TOMORROW WITH A FEW
CLOUDS AND MOSTLY SUNNY SKIES.
.LONG TERM...(FRIDAY THROUGH MONDAY)
ISSUED AT 1239 PM MDT MON MAY 26 2014
RIDGING ON THE BACKSIDE OF THE UPPER LOW MOVING ACROSS THE
SOUTHERN PLAINS WILL BE THE DOMINANT FEATURE THROUGH THE END OF
THE WEEK. DRY AND WARM CONDITIONS ARE EXPECTED AS A RESULT.
TEMPERATURES WILL BE MODERATED SOMEWHAT BY A PERSISTENT EAST TO
SOUTHEAST WIND DUE TO SURFACE HIGH PRESSURE SITUATED NEAR THE
GREAT LAKES AND TROUGHING OVER EASTERN COLORADO. HIGHS WILL
GENERALLY BE IN THE MID TO UPPER 80S AND LOWS IN THE 50S AND 60S.
NEXT CHANCE FOR PRECIPITATION ARRIVES FRIDAY NIGHT ASSUMING THE
RIDGE HAS MOVED FAR ENOUGH EAST. THOSE CHANCES WILL CONTINUE
OVER THE WEEKEND WITH A SERIES OF SHORTWAVE TROUGHS COMING OUT
OF THE SOUTHWEST AND STALLED FRONTAL BOUNDARY AT THE SURFACE. BASIC
SEVERE PARAMETERS SHOW MODERATE INSTABILITY AND WEAK TO MODERATE DEEP
LAYER SHEAR...SO A FEW SEVERE STORMS CANNOT BE RULED OUT. BY
MONDAY MODELS IN POOR AGREEMENT WITH GFS BRINGING A DRY SLOT OVER
THE CENTRAL PLAINS BUT THE ECMWF REMAINING MOIST AND UNSTABLE.
WILL GO WITH PERSISTENCE AND CARRY LOW CHANCES FOR THUNDERSTORMS
THROUGH THE END OF THE PERIOD. TEMPERATURES WILL CONTINUE TO BE
ABOVE NORMAL.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON)
ISSUED AT 1114 AM MDT TUE MAY 27 2014
VFR CONDITIONS WILL PREVAIL THROUGH THE TAF PERIOD AS AN UPPER
LEVEL RIDGE OF HIGH PRESSURE MOVES OVER THE HIGH PLAINS. A VERY
WEAK SHORTWAVE TROUGH COULD CLIP THE NORTHEAST EDGE OF THE CWA THIS
AFTERNOON...BUT WAS NOT CONFIDENT ENOUGH IN PRECIP RESULTING FROM
IT AT KMCK. THEREFORE...WENT WITH INCREASING CLOUDS THIS AFTERNOON
WHICH ARE ALREADY APPARENT ON SATELLITE AND FROM THE OFFICE.
INCLUDED A SCATTERED CUMULUS FIELD AT KGLD AND A BROKEN CUMULUS
FIELD AT KMCK FROM 20Z/21Z TO 02Z TONIGHT. WINDS WILL REMAIN ON
THE LIGHT SIDE THIS AFTERNOON INTO TOMORROW MORNING. WINDS WILL
INITIALLY BE FROM THE EAST NORTHEAST BETWEEN 5 TO 10 KTS SHIFTING
TO THE EAST SOUTHEAST THIS EVENING AND THEN TO THE SOUTHWEST BY
MORNING.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
SHORT TERM...ALW
LONG TERM...MCK
AVIATION...ALW
AREA FORECAST DISCUSSION
NWS GOODLAND KS
1100 PM MDT MON MAY 26 2014
.SHORT TERM...(THIS AFTERNOON THROUGH TUESDAY)
ISSUED AT 1155 AM MDT MON MAY 26 2014
LATEST WV IMAGERY AND RAP UPPER LEVEL ANALYSIS SHOWS UPPER LOW
CENTERED OVER NE NEW MEXICO WITH PLUME OF MOISTURE STILL MOVING
NORTH AND WEST ACROSS THE PLAINS AROUND THE EASTERN EDGE OF THIS
FEATURE. SHOWERS/THUNDERSTORMS HAVE DEVELOPED ACROSS SW KANSAS IN
RESPONSE TO STEEP LOW LEVEL LAPSE RATES AND COLD POOL ALOFT.
THIS ACTIVITY SHOULD CONTINUE TO INCREASE IN COVERAGE AS IT SPREADS
NORTH AND ADDITIONAL SHOWERS/THUNDERSTORMS SHOULD DEVELOP LOCALLY
OVER OUR CWA. I STILL THINK SCATTERED COVERAGE IS
APPROPRIATE...THOUGH GUIDANCE CONTINUES TO INDICATE A VORT MAX
AIDING IN THUNDERSTORM DEVELOPMENT ACROSS THE EASTERN CWA LATER THIS
AFTERNOON. WILL NEED TO MONITOR FOR FURTHER ADJUSTMENTS. MODERATE SB
CAPE HAS DEVELOPED ACROSS THE NORTHERN AND EASTERN CWA...AND COULD
HELP LEAD TO A FEW STRONGER STORMS. SHEER IS STILL VERY WEAK...SO
OTHER THAN MARGINAL HAIL/WIND OR LOCALLY HEAVY RAIN (LOCALIZED
FLOODING)...THERE SHOULDNT BE A WELL ORGANIZED SEVERE THREAT.
AMENDED HWO TO MENTION THIS LIMITED THREAT WITH BETTER INSTABILITY
IN PLACE THAN ORIGINALLY ANTICIPATED. AS MENTIONED IN PREVIOUS
DISCUSSION...NON-SUPERCELL TORNADO THREAT EXISTS WITH COLD POOL
DOMINATED/UPPER LOW ACROSS PLAINS...HOWEVER THIS FAR NORTH THE
THREAT IS SO LOW IT IS NOT WORTH MENTIONING BEYOND THIS DISCUSSION
AT THIS POINT.
AS UPPER LOW FINALLY BEGINS TO SHIFT EAST AND RIDGE DEVELOPS INTO
THE CWA...LARGE SCALE SUBSIDENCE ALONG WITH A QUICKLY STABILIZING
POST SUNSET AIR MASS WILL HELP END SHOWER/THUNDERSTORM THREAT FROM
THE WEST TO THE EAST. THERE IS STILL A LITTLE BIT OF UPPER LEVEL
FORCING IN PLACE LATER TONIGHT IN THE EAST...SO I DID KEEP A SLIGHT
CHANCE LINGERING A LITTLE LONGER THERE...OTHERWISE I WENT WITH A
PREDOMINATELY DRY FORECAST AFTER MIDNIGHT. DRY CONDITIONS AND MUCH
ABOVE NORMAL TEMPS (MID-UPPER 80S) ARE THEN EXPECTED ACROSS THE THE
CWA ON TUESDAY.
.LONG TERM...(TUESDAY NIGHT THROUGH MONDAY)
ISSUED AT 1239 PM MDT MON MAY 26 2014
RIDGING ON THE BACKSIDE OF THE UPPER LOW MOVING ACROSS THE
SOUTHERN PLAINS WILL BE THE DOMINANT FEATURE THROUGH THE END OF
THE WEEK. DRY AND WARM CONDITIONS ARE EXPECTED AS A RESULT.
TEMPERATURES WILL BE MODERATED SOMEWHAT BY A PERSISTENT EAST TO
SOUTHEAST WIND DUE TO SURFACE HIGH PRESSURE SITUATED NEAR THE
GREAT LAKES AND TROUGHING OVER EASTERN COLORADO. HIGHS WILL
GENERALLY BE IN THE MID TO UPPER 80S AND LOWS IN THE 50S AND 60S.
NEXT CHANCE FOR PRECIPITATION ARRIVES FRIDAY NIGHT ASSUMING THE
RIDGE HAS MOVED FAR ENOUGH EAST. THOSE CHANCES WILL CONTINUE
OVER THE WEEKEND WITH A SERIES OF SHORTWAVE TROUGHS COMING OUT
OF THE SOUTHWEST AND STALLED FRONTAL BOUNDARY AT THE SURFACE. BASIC
SEVERE PARAMETERS SHOW MODERATE INSTABILITY AND WEAK TO MODERATE DEEP
LAYER SHEAR...SO A FEW SEVERE STORMS CANNOT BE RULED OUT. BY
MONDAY MODELS IN POOR AGREEMENT WITH GFS BRINGING A DRY SLOT OVER
THE CENTRAL PLAINS BUT THE ECMWF REMAINING MOIST AND UNSTABLE.
WILL GO WITH PERSISTENCE AND CARRY LOW CHANCES FOR THUNDERSTORMS
THROUGH THE END OF THE PERIOD. TEMPERATURES WILL CONTINUE TO BE
ABOVE NORMAL.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT)
ISSUED AT 1100 PM MDT MON MAY 26 2014
VFR THROUGH THE PERIOD AT KGLD AND KMCK.
KGLD...LIGHT SOUTHWEST WINDS AT TAF ISSUANCE WILL GRADUALLY VEER
TO THE WEST BY 09Z...NORTH AT 15Z AND NORTHEAST AROUND 18Z ALL
UNDER 10KTS. AFTER 02Z WINDS BECOME VRB06KTS.
KMCK...LIGHT SOUTHWEST WINDS AT TAF ISSUANCE WILL BECOME VARIBLE
AROUND 4KTS FROM 10Z THROUGH THE REST OF THE TAF PERIOD.
NO PRECIPITATION EXPECTED AT EITHER TERMINAL.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
SHORT TERM...DR
LONG TERM...024
AVIATION...99
AREA FORECAST DISCUSSION...UPDATED
NWS JACKSON KY
816 AM EDT TUE MAY 27 2014
.UPDATE...
ISSUED AT 755 AM EDT TUE MAY 27 2014
HOURLY GRIDS HAVE BEEN FRESHENED UP BASED ON THE LATEST OBS AND TO
ACCOUNT FOR TRENDS IN THE CONVECTION OVER THE EASTERN PART OF THE
CWA. THE POPS FOR THE REMAINDER OF THE DAY HAVE BEEN TRENDED TOWARD
RECENT HRRR AND NAM RUNS. THIS LED TO SLIGHTLY LOWER POPS ACROSS MUCH
OF THE AREA.
&&
.SHORT TERM...(TODAY THROUGH WEDNESDAY)
ISSUED AT 345 AM EDT TUE MAY 27 2014
SPLIT FLOW REMAINS ACROSS THE CONUS WITH AN UPPER LEVEL LOW WORKING
ACROSS THE SOUTHERN PLAINS WHILE THE WESTERLIES ARE DISPLACE FROM THE
PACIFIC COAST GENERALLY EAST NEAR THE US CANADIAN BORDER...BEFORE
DIPPING INTO THE NORTHEASTERN US. UPPER LEVEL RIDGING EXTENDS NORTH
FROM THE GULF OF MEXICO AND SOUTHEASTERN CONUS INTO THE SOUTHERN
APPALACHIANS AND LOWER OH VALLEY REGION. LYING GENERALLY JUST TO THE
SOUTH OF THESE WESTERLIES WAS A BOUNDARY FROM LOW PRESSURE SOUTHEAST
OF THE MARITIMES TO ANOTHER SFC LOW OVER SOUTHEAST QUEBEC AND THEN
WEST SOUTHEAST FROM THAT LOW INTO THE NORTHERN GREAT LAKES AND UPPER
MS VALLEY AND NORTHERN PLAINS.
THROUGH WED...THE RIDGING OVER THE GULF OF MEXICO AND SOUTHEASTERN
CONUS WILL SHIFT FURTHER SOUTH AND DAMPEN WHILE DISTURBANCES IN THE
WESTERLIES LEAD TO A GRADUAL LOWERING OF HEIGHTS ACROSS THE SOUTHERN
GREAT LAKES REGION...PARTS OF THE OH VALLEY AND MID ATLANTIC STATES.
AT THE SAME TIME...THE UPPER LEVEL LOW WILL MEANDER TO THE ARKLATEX
REGION BY THE END OF THE PERIOD WHILE A WEAKER MID LEVEL TROUGH
APPROACHES THE OH RIVER VALLEY. AT THE SFC...THE SFC LOW INITIALLY
OVER QUEBEC WILL DROP SOUTHEAST TO THE MID ATLANTIC STATES THROUGH
DAWN ON WED. THE TRAILING COLD FRONT WILL GRADUALLY DROP TOWARD
NORTHERN AND NORTHEASTERN KY BY THE END OF THE PERIOD.
MOST OF THE MODELS HAVE CONVECTION DEVELOPING PRIOR TO DAWN...THOUGH
THE RAP IS HANDLING THE CURRENT CONVECTION A BIT BETTER THAN THE
HRRR. BOTH THE RAP AND HRRR POINT TOWARD THE ACTIVITY GRADUALLY
SHIFTING INTO THE SOUTHEAST PART OF THE CWA OR DEVELOPING IN THAT
AREA PRIOR TO DAWN AND LINGERING A BIT INTO THE DAY ON TUESDAY. THE
HRRR AND SOME OF THE OTHER GUIDANCE INCLUDING THE 0Z NAM HAD SOME
CONVECTION FROM THE LOZ AND SME AREA SOUTHEAST TOWARD THE HIGHER
TERRAIN OF HARLAN AND LETCHER COUNTY. ALTHOUGH THE CONVECTION SO FAR
HAS BEEN OVER THE EASTERN BLUEGRASS REGION...ADDITIONAL DEVELOPMENT
JUST ABOUT ANYWHERE IS POSSIBLE THROUGH AROUND DAWN. THE OVERALL
MODEL CONSENSUS IS FOR THIS TO AFFECT PARTS OF THE BIG SANDY REGION
AND PARTS OF THE VA BORDER OVER THE NEXT 4 TO 6 HOURS AND WENT WITH
THE HIGHEST POPS IN THOSE AREAS.
OTHERWISE...CONVECTION SHOULD HAVE A MAINLY DIURNAL TREND TODAY AND
INTO TONIGHT AS A WEAK SHORTWAVE IS PROGGED TO WORK AROUND THE
RIDGING OVER THE SOUTHEAST CONUS AND AFFECT THE OH VALLEY REGION
AROUND PEAK HEATING. ONCE GAIN TONIGHT...CONVECTION CANNOT BE RULED
OUT AS MID LEVEL HEIGHTS ARE PROGGED TO LOWER.
A COLD FRONT SAGGING INTO THE OH VALLEY REGION AND A WEAK MID LEVEL
SHORTWAVE MAY PROVIDE A FOCUS FOR CONVECTION...ESPECIALLY LATER IN
THE DAY ON WED IN THE CENTRAL AND NORTH. MODELS HAVE SOME HEIGHT
RISES BACK INTO EAST TN AND INTO SOUTH CENTRAL KY DURING THE DAY ON
WED AS THE RIDGE AXIS FROM THE SOUTHEASTERN RIDGE SHOULD EXTEND BACK
IN THAT DIRECTION BY THE END OF THE PERIOD. CONFIDENCE IN CONVECTION
IN THE SOUTHWEST PART OF THE CWA IS THE LOWEST FOR WED. SOME OF THAT
AREA COULD EXPERIENCE MORE SCATTERED CONVECTION RATHER THAN LIKELY
COVERAGE.
TEMPERATURES THROUGH THE PERIOD WILL REMAIN MILD FOR LATE MAY...ABOUT
5 TO 10 DEGREE ABOVE NORMAL. HIGHS TODAY WILL BE IN THE MID 80S ON
AVERAGE. CLOUD COVER SHOULD BE HIGHER ON AVERAGE ON WED...AND HOLD
TEMPS INTO THE LOW TO MID 80S. IF SKIES WERE TO CLEAR TONIGHT OR IF
WERE TO REMAIN GENERALLY FREE OF CONVECTION...TUE NIGHT...VALLEY FOG
COULD BECOME A CONCERN AND TEMPS MIGHT DISPLAY MORE OF A MODERATE
RIDGE/VALLEY SPLIT RANGE.
.LONG TERM...(WEDNESDAY NIGHT THROUGH MONDAY)
ISSUED AT 328 AM EDT TUE MAY 27 2014
THE MODELS WERE IN DECENT AGREEMENT THROUGHOUT THE EXTENDED...WITH
SIMILAR DETAILS REGARDING THE OVERALL LARGE SCALE WEATHER
PATTERN...SMALLER SCALE DETAILS...AND TIMING OF SYSTEM MOVEMENT AND
PRECIPITATION EVOLUTION. THE PERIOD IS PROGGED TO START OUT WITH
TROUGHS OF LOW PRESSURE DEVELOPING OVER THE CENTRAL GULF COAST AND
PACIFIC NORTHWEST...A RIDGE OF HIGH PRESSURE OVER THE SOUTHERN
ROCKIES...AND ANOTHER RIDGE SITUATED OVER NORTHERN NEW ENGLAND. THE
LATEST MODEL DATA SUGGEST THAT A FRONTAL BOUNDARY WILL BECOME
ESTABLISHED FROM THE MID ATLANTIC REGION WESTWARD TO THE SOUTHERN
PLAINS. THIS BOUNDARY WILL BRING PERIODS OF SHOWERS AND STORMS TO
EASTERN KENTUCKY THROUGH FRIDAY NIGHT. A NORTHERN PLAINS RIDGE WILL
BEGIN TO PUSH THE FRONT SOUTH AND OUT OF THE AREA BY FRIDAY EVENING.
THE RIDGE SHOULD KEEP THINGS DRY ACROSS THE AREA FROM FRIDAY EVENING
THROUGH SUNDAY EVENING. ANOTHER COLD FRONT IS PROGGED TO EVENTUALLY
DISPLACE THE RIDGE TO BEGIN THE NEW WORK WEEK...AND WOULD BRING MORE
SHOWERS AND STORMS TO THE AREA SHOULD THE MODELS TURN OUT TO BE
CORRECT. FOR NOW...WILL GO WITH CHANCES OF SHOWERS AND STORMS FOR
MOST OF THE PERIOD...WITH THE PEAK ACTIVITY OCCURRING DURING THE
AFTERNOON PEAK HEATING HOURS AND LULLS DURING THE OVERNIGHT PERIODS.
THE EXCEPTION TO THIS WILL BE OVER THE WEEKEND WHEN A RIDGE OF HIGH
PRESSURE WILL SETTLE OVER THE AREA...BRINGING WARM AND DRY WEATHER
TO EASTERN KENTUCKY. TEMPERATURES THROUGHOUT THE PERIOD SHOULD BE
ABOVE NORMAL SLIGHTLY ABOVE NORMAL AS REPEATED INVASIONS OF HIGH
PRESSURE DRY THINGS OUT. HIGHS WILL BE GENERALLY BE IN THE LOW TO
MID 80S AND OVERNIGHT LOWS IN THE 60S.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z WEDNESDAY MORNING)
ISSUED AT 755 AM EDT TUE MAY 27 2014
A TYPICAL SUMMERTIME PATTERN IS ANTICIPATED THROUGH THU. INITIAL
CONVECTION SHOULD AFFECT THE FAR EASTERN CWA THROUGH THE 13Z TO 14Z
PERIOD. THEN...A LULL SHOULD OCCUR THROUGH 16Z- 17Z...WHEN COVERAGE
IS EXPECTED TO INCREASE TO SCATTERED. FROM ABOUT 22Z ON...COVERAGE
SHOULD DIMINISH TO ISOLATED ONCE AGAIN...THOUGH SOME LATE NIGHT
CONVECTION AFTER ABOUT 6Z IS AGAIN POSSIBLE. CONDITIONS WILL REMAIN
VFR OTHER THAN IFR OR MVFR IN HEAVIER SHRA AND TSRA.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...JP
SHORT TERM...JP
LONG TERM...AR
AVIATION...JP
AREA FORECAST DISCUSSION
NWS JACKSON KY
409 AM EDT TUE MAY 27 2014
.SHORT TERM...(TODAY THROUGH WEDNESDAY)
ISSUED AT 345 AM EDT TUE MAY 27 2014
SPLIT FLOW REMAINS ACROSS THE CONUS WITH AN UPPER LEVEL LOW WORKING
ACROSS THE SOUTHERN PLAINS WHILE THE WESTERLIES ARE DISPLACE FROM THE
PACIFIC COAST GENERALLY EAST NEAR THE US CANADIAN BORDER...BEFORE
DIPPING INTO THE NORTHEASTERN US. UPPER LEVEL RIDGING EXTENDS NORTH
FROM THE GULF OF MEXICO AND SOUTHEASTERN CONUS INTO THE SOUTHERN
APPALACHIANS AND LOWER OH VALLEY REGION. LYING GENERALLY JUST TO THE
SOUTH OF THESE WESTERLIES WAS A BOUNDARY FROM LOW PRESSURE SOUTHEAST
OF THE MARITIMES TO ANOTHER SFC LOW OVER SOUTHEAST QUEBEC AND THEN
WEST SOUTHEAST FROM THAT LOW INTO THE NORTHERN GREAT LAKES AND UPPER
MS VALLEY AND NORTHERN PLAINS.
THROUGH WED...THE RIDGING OVER THE GULF OF MEXICO AND SOUTHEASTERN
CONUS WILL SHIFT FURTHER SOUTH AND DAMPEN WHILE DISTURBANCES IN THE
WESTERLIES LEAD TO A GRADUAL LOWERING OF HEIGHTS ACROSS THE SOUTHERN
GREAT LAKES REGION...PARTS OF THE OH VALLEY AND MID ATLANTIC STATES.
AT THE SAME TIME...THE UPPER LEVEL LOW WILL MEANDER TO THE ARKLATEX
REGION BY THE END OF THE PERIOD WHILE A WEAKER MID LEVEL TROUGH
APPROACHES THE OH RIVER VALLEY. AT THE SFC...THE SFC LOW INITIALLY
OVER QUEBEC WILL DROP SOUTHEAST TO THE MID ATLANTIC STATES THROUGH
DAWN ON WED. THE TRAILING COLD FRONT WILL GRADUALLY DROP TOWARD
NORTHERN AND NORTHEASTERN KY BY THE END OF THE PERIOD.
MOST OF THE MODELS HAVE CONVECTION DEVELOPING PRIOR TO DAWN...THOUGH
THE RAP IS HANDLING THE CURRENT CONVECTION A BIT BETTER THAN THE
HRRR. BOTH THE RAP AND HRRR POINT TOWARD THE ACTIVITY GRADUALLY
SHIFTING INTO THE SOUTHEAST PART OF THE CWA OR DEVELOPING IN THAT
AREA PRIOR TO DAWN AND LINGERING A BIT INTO THE DAY ON TUESDAY. THE
HRRR AND SOME OF THE OTHER GUIDANCE INCLUDING THE 0Z NAM HAD SOME
CONVECTION FROM THE LOZ AND SME AREA SOUTHEAST TOWARD THE HIGHER
TERRAIN OF HARLAN AND LETCHER COUNTY. ALTHOUGH THE CONVECTION SO FAR
HAS BEEN OVER THE EASTERN BLUEGRASS REGION...ADDITIONAL DEVELOPMENT
JUST ABOUT ANYWHERE IS POSSIBLE THROUGH AROUND DAWN. THE OVERALL
MODEL CONSENSUS IS FOR THIS TO AFFECT PARTS OF THE BIG SANDY REGION
AND PARTS OF THE VA BORDER OVER THE NEXT 4 TO 6 HOURS AND WENT WITH
THE HIGHEST POPS IN THOSE AREAS.
OTHERWISE...CONVECTION SHOULD HAVE A MAINLY DIURNAL TREND TODAY AND
INTO TONIGHT AS A WEAK SHORTWAVE IS PROGGED TO WORK AROUND THE
RIDGING OVER THE SOUTHEAST CONUS AND AFFECT THE OH VALLEY REGION
AROUND PEAK HEATING. ONCE GAIN TONIGHT...CONVECTION CANNOT BE RULED
OUT AS MID LEVEL HEIGHTS ARE PROGGED TO LOWER.
A COLD FRONT SAGGING INTO THE OH VALLEY REGION AND A WEAK MID LEVEL
SHORTWAVE MAY PROVIDE A FOCUS FOR CONVECTION...ESPECIALLY LATER IN
THE DAY ON WED IN THE CENTRAL AND NORTH. MODELS HAVE SOME HEIGHT
RISES BACK INTO EAST TN AND INTO SOUTH CENTRAL KY DURING THE DAY ON
WED AS THE RIDGE AXIS FROM THE SOUTHEASTERN RIDGE SHOULD EXTEND BACK
IN THAT DIRECTION BY THE END OF THE PERIOD. CONFIDENCE IN CONVECTION
IN THE SOUTHWEST PART OF THE CWA IS THE LOWEST FOR WED. SOME OF THAT
AREA COULD EXPERIENCE MORE SCATTERED CONVECTION RATHER THAN LIKELY
COVERAGE.
TEMPERATURES THROUGH THE PERIOD WILL REMAIN MILD FOR LATE MAY...ABOUT
5 TO 10 DEGREE ABOVE NORMAL. HIGHS TODAY WILL BE IN THE MID 80S ON
AVERAGE. CLOUD COVER SHOULD BE HIGHER ON AVERAGE ON WED...AND HOLD
TEMPS INTO THE LOW TO MID 80S. IF SKIES WERE TO CLEAR TONIGHT OR IF
WERE TO REMAIN GENERALLY FREE OF CONVECTION...TUE NIGHT...VALLEY FOG
COULD BECOME A CONCERN AND TEMPS MIGHT DISPLAY MORE OF A MODERATE
RIDGE/VALLEY SPLIT RANGE.
.LONG TERM...(WEDNESDAY NIGHT THROUGH MONDAY)
ISSUED AT 328 AM EDT TUE MAY 27 2014
THE MODELS WERE IN DECENT AGREEMENT THROUGHOUT THE EXTENDED...WITH
SIMILAR DETAILS REGARDING THE OVERALL LARGE SCALE WEATHER
PATTERN...SMALLER SCALE DETAILS...AND TIMING OF SYSTEM MOVEMENT AND
PRECIPITATION EVOLUTION. THE PERIOD IS PROGGED TO START OUT WITH
TROUGHS OF LOW PRESSURE DEVELOPING OVER THE CENTRAL GULF COAST AND
PACIFIC NORTHWEST...A RIDGE OF HIGH PRESSURE OVER THE SOUTHERN
ROCKIES...AND ANOTHER RIDGE SITUATED OVER NORTHERN NEW ENGLAND. THE
LATEST MODEL DATA SUGGEST THAT A FRONTAL BOUNDARY WILL BECOME
ESTABLISHED FROM THE MID ATLANTIC REGION WESTWARD TO THE SOUTHERN
PLAINS. THIS BOUNDARY WILL BRING PERIODS OF SHOWERS AND STORMS TO
EASTERN KENTUCKY THROUGH FRIDAY NIGHT. A NORTHERN PLAINS RIDGE WILL
BEGIN TO PUSH THE FRONT SOUTH AND OUT OF THE AREA BY FRIDAY EVENING.
THE RIDGE SHOULD KEEP THINGS DRY ACROSS THE AREA FROM FRIDAY EVENING
THROUGH SUNDAY EVENING. ANOTHER COLD FRONT IS PROGGED TO EVENTUALLY
DISPLACE THE RIDGE TO BEGIN THE NEW WORK WEEK...AND WOULD BRING MORE
SHOWERS AND STORMS TO THE AREA SHOULD THE MODELS TURN OUT TO BE
CORRECT. FOR NOW...WILL GO WITH CHANCES OF SHOWERS AND STORMS FOR
MOST OF THE PERIOD...WITH THE PEAK ACTIVITY OCCURRING DURING THE
AFTERNOON PEAK HEATING HOURS AND LULLS DURING THE OVERNIGHT PERIODS.
THE EXCEPTION TO THIS WILL BE OVER THE WEEKEND WHEN A RIDGE OF HIGH
PRESSURE WILL SETTLE OVER THE AREA...BRINGING WARM AND DRY WEATHER
TO EASTERN KENTUCKY. TEMPERATURES THROUGHOUT THE PERIOD SHOULD BE
ABOVE NORMAL SLIGHTLY ABOVE NORMAL AS REPEATED INVASIONS OF HIGH
PRESSURE DRY THINGS OUT. HIGHS WILL BE GENERALLY BE IN THE LOW TO
MID 80S AND OVERNIGHT LOWS IN THE 60S.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT)
ISSUED AT 200 AM EDT TUE MAY 27 2014
A TYPICAL SUMMERTIME PATTERN IS ANTICIPATED THROUGH THU. INITIAL CONCERNS
ARE FOR FOG DEVELOPMENT OVERNIGHT. THIS SHOULD FAVOR AREAS HIT WITH
SHOWERS/STORMS ON MON...MAINLY LOZ. THIS FOG HAD BEEN SLOW TO
FORM...BUT SOME MVFR HAS OCCURRED AT TIMES...AND SOME IFR STILL COULD
OCCUR THERE. HOWEVER...IF CONVECTION DEVELOPS OVER THE NEXT FEW HOURS
ISOLATED SHRA/TSRA MAY AFFECT SOME OF THE TAF SITES THROUGH 14Z. AT THIS
POINT...LOZ...JKL AND SJS APPEAR TO BE MOST FAVORED. DEPENDING ON
CONVECTION EVOLUTION...SJS AND JKL MAY EXPERIENCE FOG LIFTING IN FROM
NEARBY VALLEYS. WE HAVE CONTINUED THE TREND TOWARD AN INCREASE IN MID
CLOUDS FROM ABOUT 10Z ON...WHICH ALSO SHOULD HELP FOG SCATTER OUT AT
LOZ...AND THE OTHER TAF STIES. ANY STORMS SHOULD REMAIN ISOLATED
UNTIL 16Z-17Z...WHEN COVERAGE IS EXPECTED TO INCREASE TO SCATTERED.
FROM ABOUT 22Z ON...COVERAGE SHOULD DIMINISH TO ISOLATED ONCE AGAIN.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...JP
LONG TERM...AR
AVIATION...JP
AREA FORECAST DISCUSSION...UPDATED
NWS JACKSON KY
207 AM EDT TUE MAY 27 2014
.UPDATE...
ISSUED AT 140 AM EDT TUE MAY 27 2014
CONFIDENCE IN THE DETAIL OF THE OVERNIGHT PERIOD IS RATHER LOW. IT
WILL LIKELY NOT BE RAIN FREE...HOWEVER. THE NEAR TERM MODELS SUCH AS
THE RAP AND HRRR AS WELL AS THE NAM AND GFS DEVELOP CONVECTION TOWARD
DAWN ACROSS PARTS OF THE CWA. THIS DEVELOPMENT MAY BE FOCUSED ALONG
OLD OUTFLOW BOUNDARIES THAT HAVE BECOME ILL DEFINED AT THIS POINT.
THE RECENT HRRR RUNS GENERALLY DEVELOP SOME CONVECTION OVER THE
CUMBERLAND VALLEY REGION OVER THE NEXT FEW HOURS AND THEN CLOSER TO
DAWN ACROSS PARTS OF THE KY RIVER VALLEY EAST INTO THE BIG SANDY
REGION. THE 0Z NAM FOCUSED CONVECTION BETWEEN JKL AND LOZ SOUTHEAST
TOWARD THE HARLAN AND LETCHER COUNTY AREA OVERNIGHT INTO EARLY ON
TUE...WITH SOME SCATTERED ACTIVITY OUTSIDE OF THAT AREA. THE GFS WAS
OVERDONE WITH CONVECTION FORM INITIALIZATION TO THIS POINT AND WAS
NOT USED. THE 4Z RUC HAS DEVELOPMENT OVER THE MIDDLE OF THE CWA
AROUND 8Z AND THEN TRANSLATES THIS EAST INTO VA AND WV SHORTLY AFTER
DAWN. OVERALL...A BLEND OF THE PREVIOUS FORECAST WITH THE CONSSHORT
AND 4Z HRRR WAS USED FOR POPS THROUGH ABOUT 15Z ON TUE. THIS LED TO A
DRY FORECAST THROUGH ABOUT 4 AM...AND THEN SLIGHT CHANCE POPS FOR
MOST AREAS AFTER THAT. SLIGHTLY HIGHER POPS WERE USED IN SOME AREAS
OF THE CUMBERLAND VALLEY AND BIG SANDY REGION...GIVING A BIT MORE
WEIGHT TO THE HRRR.
LOCATIONS THAT EXPERIENCE LESS CLOUD DEVELOPMENT OR CONVECTION OVER
THE NEXT FEW HOURS WILL BE AFFECT BY VALLEY FOG THROUGH ABOUT 8 AM.
UPDATED GRIDS AND ZFP IS ALREADY OUT.
UPDATE ISSUED AT 950 PM EDT MON MAY 26 2014
FORECAST REMAINS ON TRACK TONIGHT AND ONLY MINOR TWEAKS NEEDED.
EARLIER CONVECTION HAS DISSIPATED BUT HI-RES NEAR TERM GUIDANCE
STILL INDICATES A FEW STORMS MAY FIRE AFTER MIDNIGHT...PERHAPS AS
OUTFLOWS FROM CONVECTION NOW OVER SOUTHERN INDIANA MOVE INTO THE
AREA. THE FOCUS IN THE MODELING FOR ADDITIONAL CONVECTION IS OVER
OUR NORTHERN COUNTIES...BUT WITH NUMEROUS OUTFLOWS MEANDERING ABOUT
THE AREA WILL KEEP WITH A 20 POP IN LATER TONIGHT AREAWIDE.
&&
.SHORT TERM...(THIS EVENING THROUGH TUESDAY NIGHT)
ISSUED AT 345 PM EDT MON MAY 26 2014
THE LATEST SURFACE MAP FEATURES AN AREA OF SURFACE HIGH PRESSURE
CENTERED OFF THE CAROLINA COAST...WITH WEAK RETURN FLOW ALLOWING FOR
AN INFLUX OF GULF MOISTURE INTO THE TENNESSEE AND OHIO VALLEYS.
ALOFT...A RIDGE AXIS REMAINS POISED ACROSS THE MISSISSIPPI VALLEY...
HELPING TO KEEP CONVECTION FROM GETTING TOO STRONG.
THE MODELS REMAIN IN GOOD AGREEMENT THROUGH THE SHORT TERM...WITH THE
RIDGE AXIS GRADUALLY BREAKING DOWN AS AN UPPER LEVEL LOW CURRENTLY
CHURNING NEAR THE TX/AZ BORDER SLIDES EAST TOWARDS THE ARKLATEX
REGION THROUGH THE NEXT 36 HOURS. FOCUSING ON ANY PARTICULAR WEAK
SIGNAL OUT THERE REMAINS FUTILE...AS THE MODELS HAVE BEEN PRODUCING
CONVECTION AT JUST ABOUT ANY TIME. WILL THEREFORE STICK WITH
PERSISTENCE...KEEPING THE CONVECTION MORE DIURNALLY INFLUENCED FOR
THE MOST PART.
FOR TONIGHT...EXPECT ISOLATED TO SCATTERED CONVECTION TO WIND DOWN
EARLY IN THE EVENING...WITH PERHAPS A BIT OF OF AN UPTICK TOWARDS
DAWN WITH A WEAK LOW LEVEL JET LINGERING IN THE VICINITY AND MORE
MOISTURE TO WORK WITH COMPARED TO LAST NIGHT.
HEATING WILL ALLOW FOR MORE SCATTERED COVERAGE DURING THE DAY ON
TUESDAY...AS THE MOISTURE WILL BE JUST A BIT BETTER OVERALL ALONG
WITH A WEAKER UPPER LEVEL RIDGE IN PLACE. EXPECT A SIMILAR INITIAL DROP
OFF IN ACTIVITY TUESDAY EVENING BEFORE PERHAPS A SLIGHT INCREASE
ONCE AGAIN TOWARDS DAWN EARLY WEDNESDAY MORNING.
LOWS TONIGHT AND TUESDAY NIGHT WILL BE MORE BALMY...GENERALLY IN THE
LOW TO MID 60S...WITH HIGHS ON TUESDAY IN THE LOW TO MID 80S.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 345 PM EDT MON MAY 26 2014
UPPER LEVEL PATTERN REMAINS ON COURSE THROUGH THE EXTENDED...WITH A
WEAK OMEGA BLOCK PUTTING A RIDGE ACROSS MUCH OF THE NORTHERN CONUS
AND TWO CLOSED LOWS OFF THE NORTH PACIFIC AND ATLANTIC COASTS. THIS
RIDGE WILL BE FURTHER AMPLIFIED OVER THE OHIO RIVER VALLEY AS
ANOTHER CLOSED LOW CONTINUES TO ROTATE IN THE TEXAS/OKLAHOMA AREA.
AS WE HEAD INTO THE START OF THE PERIOD AT 12Z WEDNESDAY...THE UPPER
LEVEL LOW OVER TEXAS AND OKLAHOMA WILL HAVE SHIFTED
SOUTHWARD...REACHING EAST TEXAS AND LOUISIANA AND THEN REMAINING
FAIRLY STATIONARY FOR MUCH OF THE REST OF THE WEEK. THIS SHIFT
SOUTHWARD WILL ALLOW THE TROUGHING PATTERN OVER THE NE TO ALSO SHIFT
SLIGHTLY SOUTHWARD. AT THE SURFACE...A WEAK BACKDOOR COLD FRONT WILL
SHIFT FROM THE NE TO THE SW...PASSING INTO EASTERN KY BY WEDNESDAY
AFTERNOON/EVENING. AND THEN JUST AS THE CLOSED LOW BECOMES
STATIONARY TO OUR SW...SO WILL TO THIS FRONTAL BOUNDARY ACROSS SOUTH
AND WESTERN KY.
ALTHOUGH THIS BOUNDARY WILL BE WEAK...WITH LITTLE CHANGES EXPECTED
IN THE WAY OF TEMPERATURES THROUGHOUT THE REMAINDER OF THE EXTENDED
/SHOULD STAY AROUND THE LOW 80S WITH THE WARM GULF AIR FILTERING
IN/...IT WILL BE ENOUGH TO ALLOW FOR LIFT AND SCATTERED TO NUMEROUS
SHOWER AND THUNDERSTORM DEVELOPMENT WEDNESDAY AND THURSDAY...MAINLY
IN THE AFTERNOON WITH THE PEAK
INSTABILITY/HEATING. CONTINUED CHANCES OF AFTERNOON SHOWERS AND
THUNDERSTORMS WILL BE POSSIBLE FRIDAY AS WELL...THOUGH BY SATURDAY
THE BOUNDARY SHOULD FINALLY DROP JUST ENOUGH SOUTHWARD THAT DRY AIR
WILL BEGIN TO FILTER IN TO THE NORTH AND THEN OVERSPREAD MUCH OF THE
REGION BY SUNDAY. `
BY MONDAY...A SHORT WAVE WILL WORK IN FROM THE NE...BRINGING YET
ANOTHER CHANCE FOR SHOWERS AND THUNDERSTORMS DURING THE DAY. THOUGH
AT THIS POINT...MODELS SEEM QUITE DIVERGENT IN UPPER LEVEL
SOLUTIONS...SO WILL STICK CLOSE TO THE ALLBLEND GUIDANCE AT THIS
TIME.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT)
ISSUED AT 200 AM EDT TUE MAY 27 2014
A TYPICAL SUMMERTIME PATTERN IS ANTICIPATED THROUGH THU. INITIAL CONCERNS
ARE FOR FOG DEVELOPMENT OVERNIGHT. THIS SHOULD FAVOR AREAS HIT WITH
SHOWERS/STORMS ON MON...MAINLY LOZ. THIS FOG HAD BEEN SLOW TO
FORM...BUT SOME MVFR HAS OCCURRED AT TIMES...AND SOME IFR STILL COULD
OCCUR THERE. HOWEVER...IF CONVECTION DEVELOPS OVER THE NEXT FEW HOURS
ISOLATED SHRA/TSRA MAY AFFECT SOME OF THE TAF SITES THROUGH 14Z. AT THIS
POINT...LOZ...JKL AND SJS APPEAR TO BE MOST FAVORED. DEPENDING ON
CONVECTION EVOLUTION...SJS AND JKL MAY EXPERIENCE FOG LIFTING IN FROM
NEARBY VALLEYS. WE HAVE CONTINUED THE TREND TOWARD AN INCREASE IN MID
CLOUDS FROM ABOUT 10Z ON...WHICH ALSO SHOULD HELP FOG SCATTER OUT AT
LOZ...AND THE OTHER TAF STIES. ANY STORMS SHOULD REMAIN ISOLATED
UNTIL 16Z-17Z...WHEN COVERAGE IS EXPECTED TO INCREASE TO SCATTERED.
FROM ABOUT 22Z ON...COVERAGE SHOULD DIMINISH TO ISOLATED ONCE AGAIN.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...JP
SHORT TERM...GEOGERIAN
LONG TERM...JMW
AVIATION...JP
AREA FORECAST DISCUSSION
NWS LAKE CHARLES LA
1158 PM CDT MON MAY 26 2014
.DISCUSSION...
FOR THE 06Z TAF PACKAGE.
&&
.AVIATION...
AREAS OF LIGHT RAIN ARE ALL THAT REMAINS OVER EARLIER EAST TEXAS
CONVECTION...WHICH THE HRRR DID A FINE JOB WITH THIS EVENING.
LATEST HIGH RESOLUTION AND GLOBAL MODELS DEPICT CONVECTION
OCCURRING BY MID TO LATE MORNING ACROSS SE TX/SW LA...SPREADING
EAST THROUGH THE AFTERNOON AND EARLY EVENING HOURS. FIRST 12 HOURS
OR SO OF PREVIOUS FORECASTS WERE LEFT INTACT...WITH TEMPO MVFR OR
PREVAILING MVFR DURING THE OVERNIGHT/EARLY MORNING HOURS. THE
ADDITIONS INCLUDED PROB30S AT ALL SITES FOR THE EXPECTED
CONVECTION TOMORROW...WHICH WILL LIKELY BECOME PREVAILING IN
SUBSEQUENT FORECASTS AS CONFIDENCE INCREASES IN TIMING AND SPATIAL
EXTENT.
13
&&
.PREV DISCUSSION... /ISSUED 748 PM CDT MON MAY 26 2014/
DISCUSSION...
FOR THE 00Z TAF PACKAGE.
AVIATION...
LARGE AREA OF SHOWERS AND EMBEDDED THUNDERSTORMS CONTINUES TO
CHURN ACROSS EASTERN TEXAS FROM THE HOUSTON AREA NORTH TO NEAR
CARTHAGE. MOST INTENSE THUNDERSTORM ACTIVITY CURRENTLY CROSSING
GALVESTON BAY. LATEST GUIDANCE SUGGESTS THIS CONVECTION SHOULD
GRADUALLY WANE OVER THE NEXT COUPLE OF HOURS...AND RADAR/SATELLITE
TRENDS DO INDICATE THIS IS ALREADY UNDERWAY TO SOME DEGREE. WILL
CONTINUE TO MONITOR...BUT AT THIS TIME THE IMPACTS TO KBPT ARE
EXPECTED TO BE MINIMAL. OTHERWISE...NO BIG CHANGES WERE MADE FROM
THE INHERITED 18Z FORECAST...BUT DID CARRY MVFR AT KBPT AND KLCH
FOR A COUPLE OF HOURS THIS EVENING BASED ON CURRENT OBS. VFR
EXPECTED TO PREVAIL ELSEWHERE THROUGH THE EVENING...WITH TEMPO
MVFR TOWARD EARLY MORNING ALL BUT KBPT...WHERE PREVAILING MVFR WAS
RETAINED. WILL TAKE A CLOSER LOOK AT CONVECTIVE PROSPECTS TOMORROW
WITH THE 06Z ISSUANCE.
13
PREV DISCUSSION... /ISSUED 738 PM CDT MON MAY 26 2014/
DISCUSSION...
RADAR SHOWS MCS OVER SE TX MOVING EAST AT 15 TO 20 MPH ACROSS
GALVESTON BAY...ONLY WEAKENING SLIGHTLY WITHIN THE LAST HOUR.
ALONG WITH HOUSTON...BELIEVE THE SVR WX THREAT...ESPECIALLY FOR
TORNADOES...HAS DIMINISHED. THUS...CANCELLED TORNADO WATCH 189.
MOST GUIDANCE SHOWS THIS MCS CONTINUING TO WEAKEN THIS EVENING AS
IT MOVES ACROSS SE TX TOWARDS BPT & ADJACENT COASTAL WATERS. RE-
ADJUSTED POPS THIS EVENING ACROSS SE TX FOR THE WEAKENING MCS AND
ASSOCIATED RAIN SHIELD TO THE NORTH TOWARDS THE LAKES REGION.
OTHERWISE...NO OTHER CHANGES MADE.
DML
PREV DISCUSSION... /ISSUED 442 PM CDT MON MAY 26 2014/
DISCUSSION...
CLOUDS CONTINUE TO STREAM ACROSS THE REGION THIS AFTERNOON AS
STORMS OVER THE HOUSTON AREA MOVE EAST. SOME OF THESE STORMS HAVE
PRODUCED WIND DAMAGE AND WITH THE EASTWARD MOVEMENT... A TOR WATCH
WAS ISSUED FOR SOUTHEAST TEXAS COUNTIES OF HARDIN...JEFFERSON AND
ORANGE TILL 9 PM.
THE RIDGE THAT HAS BEEN IN PLACE OVER THE REGION OVER THE LAST
SEVERAL WEEKS IS FINALLY BREAKING DOWN AND SHIFTING OFF TO THE
EAST. THE APPROACH OF THE UPPER LEVEL LOW FROM THE WEST IS
SUPPORTING STORM DEVELOPMENT. THE LOW IS EXPECTED TO STALL OVER
THE REGION GIVING SE TX AND SRN LA THE FIRST REAL SHOT AT SOME
MUCH NEEDED RAINFALL. RAINFALL CHANCES WILL INCREASE ON TUESDAY
INTO WEDNESDAY AND CONTINUE THROUGH THE REST OF THE WEEK. THERE
WILL BE A CHANCE THAT SOME STORMS TOMORROW MAY HAVE THE POTENTIAL
OF BECOMING SEVERE. SINCE THIS WILL BE AN EVENT THAT LASTS FOR
FOUR TO FIVE DAYS RAINFALL TOTALS OF TWO TO THREE INCHES WILL BE
POSSIBLE WITH UPWARDS TO SIX INCHES OR MORE POSSIBLE IN ISOLATED
LOCATIONS.
&&
.PRELIMINARY POINT TEMPS/POPS...
KLCH 72 84 70 81 70 / 20 50 60 80 50
KBPT 74 85 71 83 70 / 30 50 60 70 40
KAEX 69 84 68 81 67 / 20 60 60 80 40
KLFT 72 85 71 81 71 / 20 50 60 80 40
&&
.LCH WATCHES/WARNINGS/ADVISORIES...
LA...NONE.
TX...NONE.
GM...NONE.
&&
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&&
$$
AREA FORECAST DISCUSSION
NWS CARIBOU ME
430 PM EDT TUE MAY 27 2014
.SYNOPSIS...
COOL HIGH PRESSURE WILL REMAIN TO OUR NORTH TONIGHT THEN CREST
OVER THE AREA WEDNESDAY INTO WEDNESDAY NIGHT. THE HIGH WILL MOVE
EAST OF THE REGION THURSDAY THEN A TROUGH OF LOW PRESSURE WILL
CROSS THE AREA FRIDAY.
&&
.NEAR TERM /THROUGH WEDNESDAY/...
WEAK AREA OF LOW PRES MOVING ACROSS NORTHERN NYS AS OF 18Z WHILE
AN INVERTED TROF EXTENDS OFF THIS LOW INTO WSW MAINE WHILE HIGH
PRES IS WEDGING ITS WAY DOWN ACROSS NORTHERN AND EASTERN SECTIONS
OF THE CWA. IN THE UPPER LEVELS, A DISTURBANCE WAS SWINGING ACROSS
SOUTHERN QUEBEC. THIS WILL ACT W/THE SFC FRONT TO LEAD TO SHOWER
ACTIVITY AS THE LATEST RADAR LOOP SHOWED RAIN NOW EXTENDING
FURTHER NORTH INTO NW AREAS. DECIDED TO BRING RAINFALL CHANCES
FURTHER TO THE NORTH W/THIS PACKAGE USING A BLEND OF THE RAP AND
GFS SHOWING FORCING IN THE MID LEVELS EDGING NORTH OVERNIGHT.
LEANED TOWARD A BLEND OF THE NERFC AND HPC FOR QPF TONIGHT INTO
WEDNESDAY WHICH SUPPORTS 0.15 TO 0.25" MAINLY IN WESTERN AREAS.
CLOUDS HAVE STAYED ALL THE WAY THROUGH TODAY BUT SOME DRIER AIR
WAS TRYING TO SEEP SOUTH FROM CANADA PER THE LATEST SATELLITE
IMAGERY. THE CLOUDS WILL KEEP TEMPERATURES FROM FALLING BACK BELOW
40F ESPECIALLY FOR THE WESTERN AND CENTRAL AREAS. FAR NORTHERN
AREAS WILL SEE SOME PARTIAL CLEARING TAKING PLACE AFTER MIDNIGHT
W/THAT DRYING DRAINING DOWN FROM CANADA. THIS WILL LEAD TO
TEMPERATURES BY EARLY WEDNESDAY MORNING HITTING THE MID TO UPPER
30S ACROSS FAR NORTH AND NORTHWESTERN AREAS. THEREFORE, ADDED
PATCHY FROST INTO THE FORECAST FOR THESE AREAS.
RAIN WILL SHIFT FURTHER SOUTH AS THE SURFACE AND THE UPPER LOW PASSES
TO THE EAST AND HIGH PRES WEDGES DOWN FROM CANADA. CLOUDS WILL
GRADUALLY BREAK UP FROM NORTH TO SOUTH DURING THE DAY W/THE
DOWNEAST AND THE COAST BEING THE LAST TO CLEAR OUT. THEREFORE,
THIS WILL LEAD TO QUITE A CHALLENGE W/DAYTIME TEMPERATURES AS THE
NORTHERN 1/2 F THE CWA WILL BE MUCH WARMER W/MID 60S AT LEAST AND
LOWER 60S FOR THE DOWNEAST AND THE COAST.
&&
.SHORT TERM /WEDNESDAY NIGHT THROUGH THURSDAY/...
HIGH PRESSURE WILL BUILD IN FROM THE NORTH WEDNESDAY NIGHT THEN
MOVE TO THE SOUTHWEST THURSDAY. A COLD FRONT WILL APPROACH FROM
THE NORTHWEST THURSDAY NIGHT THEN MOVE INTO THE AREA FRIDAY. THIS
FRONT IS THEN EXPECTED TO STALL OVER NEW ENGLAND WITH LOW PRESSURE
DEVELOPING ALONG THE FRONT. WILL USE A BLEND OF THE
NAM...GFS...SREF AND ECMWF TO INITIALIZE THE POPS AND QPF WITH
SOME MANUAL ADJUSTMENTS. FOR THE WIND GRIDS HAVE USED THE MOSG25.
TEMPERATURE AND DEW POINT FROM THE SUPPER BLEND.
&&
.LONG TERM /THURSDAY NIGHT THROUGH TUESDAY/...
A COLD FRONT WILL MOVE INTO NEW ENGLAND FRIDAY WITH LOW PRESSURE
DEVELOPING ALONG THE FRONT. THE LOW WILL THEN MOVE TO THE
SOUTHEAST LATE FRIDAY NIGHT AND SATURDAY. HIGH PRESSURE WILL THEN
BUILD OVER THE STATE SATURDAY NIGHT INTO SUNDAY. ANOTHER COLD
FRONT WILL THEN APPROACH FROM THE NORTHWEST SUNDAY NIGHT AND MOVE
THROUGH THE REGION MONDAY. HAVE USED THE GMOS TO POPULATE GRIDS
WITH SOME MINOR ADJUSTMENTS TO TEMPERATURES.
&&
.AVIATION /20Z TUESDAY THROUGH SUNDAY/...
NEAR TERM: VFR THIS EVENING DROPPING TO MVFR TONIGHT W/EVEN THE
POTENTIAL FOR IFR MAINLY KBGR AND KBHB. EXPECTING CONDITIONS TO
IMPROVE TO VFR BY THE AFTERNOON ON WEDNESDAY ESPECIALLY NORTH OF KHUL.
KBGR AND KBHB COULD HANG ON TO MVFR CIGS A WHILE LONGER W/A
CONTINUED EASTERLY FLOW.
SHORT TERM: EXPECT VFR CONDITIONS THURSDAY. IFR/MVFR CONDITIONS
EXPECTED FRIDAY AND SATURDAY. VFR CONDITIONS EXPECTED SUNDAY.
&&
.MARINE...
NEAR TERM: NO SCA HEADLINES FORESEEN ATTM. SOME FOG HAS DEVELOPED
ACROSS THE WATERS PER THE LATEST OB FROM 33034 W/WIND LESS THAN 10
KTS. ADDED AREAS OF FOG FOR THE WATERS FOR TONIGHT. EXPECTING VSBY
TO IMPROVE AND FOG TO CLEAR AS WINDS PICK UP FROM THE ENE ON
WEDNESDAY. KEPT SPEEDS AROUND 10 KTS TONIGHT AND DECIDED TO BRING
SPEEDS UP TO 10 TO 15 KTS. SEAS WILL STAY AT 2-3 FT.
SHORT TERM: HAVE USED THE SREF FOR SUSTAINED WIND SPEED. FOR
WAVES: PRIMARY WAVE GROUP THURSDAY WAVE GROUP THURSDAY INTO
SATURDAY WILL BE EAST TO SOUTHEAST LONG PERIOD WAVE SYSTEM AROUND
2 FEET/8-9 SECONDS. WIND WAVE IS EXPECTED TO BE SUPPRESSED THIS
PERIOD DUE TO THE BOUNDARY CONDITIONS. A MORE SIGNIFICANT
SOUTHEASTERLY FETCH IS EXPECTED TO DEVELOP OVER THE WEEKEND
SOUTHEAST OF THE GULF OF MAINE. THIS MAY PRODUCE LONG PERIOD WAVE
FROM THE SOUTHEAST AROUND 3 FEET.
&&
.CAR WATCHES/WARNINGS/ADVISORIES...
ME...NONE.
MARINE...NONE.
&&
$$
NEAR TERM...HEWITT
SHORT TERM...MIGNONE
LONG TERM...MIGNONE
AVIATION...HEWITT/MIGNONE
MARINE...HEWITT/MIGNONE
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
410 PM EDT TUE MAY 27 2014
.SHORT TERM...(THIS EVENING THROUGH WEDNESDAY)
ISSUED AT 409 PM EDT TUE MAY 27 2014
WV IMAGERY AND RUC ANALYSIS INDICATED A MID/UPPER LEVEL RIDGE FROM
THEN WRN PLAINS TO NW ONTARIO BETWEEN TROUGHS OFF THE PAC NW AND THE
CANADIAN MARITIMES. AT THE SFC...A RIDGE EXTENDED FROM WRN HUDSON BAY
INTO THE NRN GREAT LAKES. SOME LIGHT SHOWERS LINGERED OVER NRN WI
SUPPORTED BY A WEAK SHRTWV NORTH OF A FRONT LOW OVER SE MN AND FRONT
THROUGH SRN WI.
TONIGHT...EXPECT THE WI SHRTWV AND REMAINING MID CLOUDS INTO THE SRN
PORTION OF THE CWA TO DRIFT TO THE SE. AN AREA OF VERY DRY AIR WILL
DROP INTO THE NRN LAKES WITH PWAT VALUES FALLING TO NEAR 0.3 INCH.
FAVORABLE RADIATIONAL COOLING CONDITIONS WITH LIGHT WINDS AND MOSTLY
CLEAR SKIES WILL ALLOW TEMPS TO DROP TOWARD THE LOWER END OF
GUIDANCE.
WEDNESDAY...THE MID/UPPER LEVEL RIDGE WILL CONTINUE TO BUILD INTO
THE REGION AS SFC HIGH PRES ALSO DOMINATES. A STRENGTHENING
SUBSIDENCE INVERSION MAY LIMIT THE MIXING DEPTH...BUT WITH MOSTLY
SUNNY SKIES TEMPS SHOULD STILL CLIMB INTO THE MID AND UPPER 70S.
LAKE BREEZES WILL KEEP READINGS MAINLY IN THE UPPER 50S AND 60S NEAR
LAKE SUPERIOR. WITH THE VERY DRY 900-750 MB LAYER...EXPECT DEWPOINTS
WILL DROP TOWARD THE LOWER END OF GUIDANCE WITH RH DOWN TO NEAR 20
PERCENT OVER THE INTERIOR WEST.
.LONG TERM...(WEDNESDAY NIGHT THROUGH TUESDAY)
ISSUED AT 325 PM EDT TUE MAY 27 2014
MUCH OF THE LONG TERM PERIOD WILL BE DRY DUE TO CANADIAN HIGH
PRESSURE OVER THE AREA THROUGH THE FIRST PART OF THE WEEKEND.
THIS HIGH PRESSURE RIDGE...WHICH IS CURRENTLY STRETCHING SOUTHEAST
OVER THE NORTHWESTERN HALF OF UPPER MICHIGAN...WILL SLOWLY SLIDE
SOUTHEAST ACROSS THE AREA THROUGH SATURDAY (AS THE PARENT HIGH MOVES
EAST FROM CENTRAL CANADA AND INTO QUEBEC). AS THIS OCCURS...THE
UPPER RIDGE AXIS OVER ONTARIO WILL AMPLIFY AND PUT THE UPPER GREAT
LAKES UNDER IT INTO SATURDAY NIGHT. WITH THE DRY AIR ASSOCIATED WITH
THE RIDGES...EXPECT A MOSTLY CLEAR SKY TO BE IN PLACE ALTHOUGH THERE
COULD BE A FEW MID-HIGH CLOUDS THAT BRUSH THE NORTHERN HALF OF THE
CWA AT TIMES. IN ADDITION...THERE ARE A COUPLE HINTS OF SOME LOWER
LEVEL MOISTURE AND WITH DIURNAL HEATING AND LAKE BREEZES...COULD SEE
A FEW DIURNAL CU. WINDS DURING THIS PERIOD WILL BE LIGHT AND EITHER
VARIABLE OR OUT OF AT NORTHERLY DIRECTION...WHICH WITH DIURNAL
HEATING AND THE COLD GREAT LAKES TEMPERATURES...EXPECT AFTERNOON
LAKE BREEZES TO BE THE NORM ON MOST DAYS. THUS...INTERIOR LOCATIONS
WILL EXPERIENCE THE WARMEST TEMPERATURES (HIGHS GENERALLY IN THE 70S
AND LOWER 80S) WHILE THE LAKESHORES WILL WARM UP IN THE MORNING AND
THEN START COOLING BY EARLY AFTERNOON. DECENT MIXING OVER THE INLAND
AREAS WILL SUPPORT LOWER RH VALUES IN THE AFTERNOONS (MID 20S TO MID
30S PERCENT)...BUT LIGHT WINDS AND A RAPIDLY OCCURRING GREEN UP WILL
LIMIT FIRE WEATHER CONCERNS.
HEADING INTO THE WEEKEND...THE GENERAL IDEA OF A COLD FRONT SLOWLY
APPROACHING THE AREA SATURDAY NIGHT AND THEN MOVING THROUGH THE
AREA OVER THE NEXT COUPLE OF DAYS IS CONSISTENT IN THE MODELS. THE
MAIN UNCERTAINTY IS THE AMOUNT OF MOISTURE ASSOCIATED WITH THE
FRONT AND EXACT TIMING. A CONSENSUS OF THE MODELS WITH THE FRONT
MOVING THROUGH DURING THE SUNDAY INTO SUNDAY NIGHT TIME FRAME SEEMS
REASONABLE AND WILL CONTINUE TO HIGHLIGHT CHANCE POPS THEN. A BRIEF
HIGH PRESSURE RIDGE MAY MOVE OVER THE AREA BEHIND THE FRONT ON
MONDAY...BUT MODELS ARE INDICATING THE UPPER RIDGE SHIFTING EAST AND
A BROAD LOW PRESSURE SYSTEM MOVING TOWARDS THE GREAT LAKES REGION
FOR TUESDAY.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON)
ISSUED AT 128 PM EDT TUE MAY 27 2014
EXPECT VFR CONDITIONS TO DOMINATE THIS FCST PERIOD WITH A DRY NE
FLOW ON THE SOUTHERN FLANK OF HIGH PRESSURE BUILDING FROM NRN
ONTARIO INTO THE WESTERN GREAT LAKES.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 409 PM EDT TUE MAY 27 2014
WITH RELATIVELY WEAK PRES GRADIENT TYPICAL OF THE WARM SEASON
DOMINATING THRU THIS FORECAST PERIOD...EXPECT WINDS MOSTLY UNDER
20KT TO PREVAIL THROUGH SAT. SOUTH WINDS MAY NEAR OR EXCEED 20 KNOTS
BY SAT NIGHT INTO SUN AHEAD OF A FRONTAL SYSTEM APPROACHING FROM THE
NW.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...JLB
LONG TERM...SRF
AVIATION...JLB
MARINE...JLB
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
325 PM EDT TUE MAY 27 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 415 AM EDT TUE MAY 27 2014
00Z RAOBS/LATEST WV IMAGERY AND RUC ANALYSIS SHOW UPR RDG DOMINATING
THE NCENTRAL CONUS/CENTRAL CANADA BTWN TROFS OFF THE PAC NW AND THE
CNDN MARITIMES AND N OF CLOSED LO DRIFTING THRU THE SRN PLAINS. SFC
HI PRES OVER CENTRAL CANADA IS BLDG INTO NW ONTARIO...AND A N WIND
ON THE SRN FLANK OF THIS FEATURE IS ADVECTING DRIER LLVL AIR SHOWN
ON THE 00Z INL/YPL RAOBS INTO THE UPR LKS IN THE WAKE OF A SFC COLD
FROPA A BIT FASTER THAN MUCH OF THE GUIDANCE HAD INDICATED
PREVIOUSLY. WITH A NNE WIND CLOSE TO 15 MPH AT HOUGHTON...THE SFC
DEWPT FELL FM 56 AT 27/00Z TO 45 AT 27/05Z. THE 05Z SFC DEWPT
DEPRESSION WAS 14 DEGREES THERE. N WIND UP TO 24 KTS REPORTED AT
STANNARD ROCK LIGHTHOUSE HAS ENHANCED THIS LLVL DRYING TREND. THERE
WAS SOME FOG ON LK SUP EARLIER...BUT RECENT SHIP OBS/STLT IMAGERY
INDICATE PATCHY FOG LINGERS OVER PORTIONS OF ONLY ERN LK SUP. THE
LLVL DRYING HAS BEEN SLOWER TO DVLP OVER THE E AND SCENTRAL...AND
SOME LO CLDS AND FOG HAVE FORMED IN THESE AREAS. A NEARLY STNRY LINE
OF SHOWERS/SOME TS LINGERS FM SCENTRAL MN ACROSS NCENTRAL WI TO LK
MI JUST S OF MENOMINEE TO THE S OF THE SFC COLD FNT WHERE THE BULK
OF THE MODEL GUIDANCE SHOW SOME DEEP LYR QVECTOR CNVGC ASSOCIATED
WITH A WEAK SHRTWV MOVING W TO E THRU THE UPR MS RIVER VALLEY.
MAIN FCST CONCERNS IN THE SHORT TERM INVOLVE IMPACT OF CURRENT LLVL
DRYING TRENDS AND WHETHER ANY OF THE SHOWERS IN WI WL IMPACT THE SRN
COUNTIES TODAY.
TODAY...SHRTWV NOW OVER SCENTRAL MN INVIGORATING AREA OF SHOWERS TO
THE S OF UPR MI IS FCST TO DRIFT SLOWLY TO THE ESE THRU THE DAY AND
WEAKEN UNDER SLOW H5 RISES AS THE UPR RDG SLOWLY BUILDS INTO THE
CWA. ACCOMPANYING AREA OF QVECTOR CNVGC IS FCST TO FADE AWAY BY 18Z
AS A RESULT OF THE WEAKENING SHRTWV AND CONTINUED DRY ADVCTN ON THE
SRN FLANK OF THE HI PRES IN ONTARIO FCST TO BUILD INTO NCENTRAL LK
SUP THIS AFTN. CONSIDERING THE TRENDS AND THE STRONGER DRY ADVCTN
NOTED ABOVE...OPTED TO FOLLOW THE DRIER MODEL GUIDANCE ALIGNED
TOWARD THE 00Z GFS AND REMOVE POPS FM ALL BUT MENOMINEE COUNTY THIS
MRNG. IF THERE ARE ANY LO CLDS/FOG OVER MAINLY THE ERN CWA WHERE THE
LLVL DRYING HAS SO FAR BEEN MORE MARGINAL...THIS SHOULD DSPT WITH
CONTINUED DRY ADVECTION ON THE SRN FLANK OF BLDG HI PRES/DAYTIME
HEATING AND MIXING. MIXING TO H8 ON FCST SDNGS YIELDS HI TEMPS
APRCHG 80 OVER THE SCENTRAL FARTHER FM THE COOLING INFLUENCE OF LK
SUP. TEMPS NEAR THE BIG LK SHOULD HOLD IN THE 50S. DEEP MIXING OFF
THE DRIER GFS SDNGS WOULD INDICATE SFC DEWPTS COULD MIX OUT INTO THE
TEENS TODAY. GIVEN THE 00Z INL/YPL RAOBS...35 TO 45 FOR THE DEWPTS
SEEMS MORE RSNBL...RESULTING IN MIN RH FALLING AS LO AS 25 TO 30 PCT
BY LATE AFTN OVER THE INTERIOR W HALF.
TNGT...POCKET OF VERY DRY AIR IS FCST TO DROP INTO THE UPR LKS...
WITH H85-5 MEAN RH FALLING AS LO AS 20 PCT. PWAT FCST 0.33-0.50 INCH
WL BE 50-75 PCT OF NORMAL. WITH LGT WINDS/MOCLR SKIES UNDER SFC RDG
AXIS...OPTED TO TREND TOWARD THE LO END OF GUIDANCE FOR MIN TEMPS
FCST.
.LONG TERM...(WEDNESDAY NIGHT THROUGH TUESDAY)
ISSUED AT 325 PM EDT TUE MAY 27 2014
MUCH OF THE LONG TERM PERIOD WILL BE DRY DUE TO CANADIAN HIGH
PRESSURE OVER THE AREA THROUGH THE FIRST PART OF THE WEEKEND.
THIS HIGH PRESSURE RIDGE...WHICH IS CURRENTLY STRETCHING SOUTHEAST
OVER THE NORTHWESTERN HALF OF UPPER MICHIGAN...WILL SLOWLY SLIDE
SOUTHEAST ACROSS THE AREA THROUGH SATURDAY (AS THE PARENT HIGH MOVES
EAST FROM CENTRAL CANADA AND INTO QUEBEC). AS THIS OCCURS...THE
UPPER RIDGE AXIS OVER ONTARIO WILL AMPLIFY AND PUT THE UPPER GREAT
LAKES UNDER IT INTO SATURDAY NIGHT. WITH THE DRY AIR ASSOCIATED WITH
THE RIDGES...EXPECT A MOSTLY CLEAR SKY TO BE IN PLACE ALTHOUGH THERE
COULD BE A FEW MID-HIGH CLOUDS THAT BRUSH THE NORTHERN HALF OF THE
CWA AT TIMES. IN ADDITION...THERE ARE A COUPLE HINTS OF SOME LOWER
LEVEL MOISTURE AND WITH DIURNAL HEATING AND LAKE BREEZES...COULD SEE
A FEW DIURNAL CU. WINDS DURING THIS PERIOD WILL BE LIGHT AND EITHER
VARIABLE OR OUT OF AT NORTHERLY DIRECTION...WHICH WITH DIURNAL
HEATING AND THE COLD GREAT LAKES TEMPERATURES...EXPECT AFTERNOON
LAKE BREEZES TO BE THE NORM ON MOST DAYS. THUS...INTERIOR LOCATIONS
WILL EXPERIENCE THE WARMEST TEMPERATURES (HIGHS GENERALLY IN THE 70S
AND LOWER 80S) WHILE THE LAKESHORES WILL WARM UP IN THE MORNING AND
THEN START COOLING BY EARLY AFTERNOON. DECENT MIXING OVER THE INLAND
AREAS WILL SUPPORT LOWER RH VALUES IN THE AFTERNOONS (MID 20S TO MID
30S PERCENT)...BUT LIGHT WINDS AND A RAPIDLY OCCURRING GREEN UP WILL
LIMIT FIRE WEATHER CONCERNS.
HEADING INTO THE WEEKEND...THE GENERAL IDEA OF A COLD FRONT SLOWLY
APPROACHING THE AREA SATURDAY NIGHT AND THEN MOVING THROUGH THE
AREA OVER THE NEXT COUPLE OF DAYS IS CONSISTENT IN THE MODELS. THE
MAIN UNCERTAINTY IS THE AMOUNT OF MOISTURE ASSOCIATED WITH THE
FRONT AND EXACT TIMING. A CONSENSUS OF THE MODELS WITH THE FRONT
MOVING THROUGH DURING THE SUNDAY INTO SUNDAY NIGHT TIME FRAME SEEMS
REASONABLE AND WILL CONTINUE TO HIGHLIGHT CHANCE POPS THEN. A BRIEF
HIGH PRESSURE RIDGE MAY MOVE OVER THE AREA BEHIND THE FRONT ON
MONDAY...BUT MODELS ARE INDICATING THE UPPER RIDGE SHIFTING EAST AND
A BROAD LOW PRESSURE SYSTEM MOVING TOWARDS THE GREAT LAKES REGION
FOR TUESDAY.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON)
ISSUED AT 128 PM EDT TUE MAY 27 2014
EXPECT VFR CONDITIONS TO DOMINATE THIS FCST PERIOD WITH A DRY NE
FLOW ON THE SOUTHERN FLANK OF HIGH PRESSURE BUILDING FROM NRN
ONTARIO INTO THE WESTERN GREAT LAKES.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 415 AM EDT TUE MAY 27 2014
WITH RELATIVELY WEAK PRES GRADIENT TYPICAL OF THE WARM SEASON
DOMINATING THRU THIS FORECAST PERIOD...EXPECT WINDS MOSTLY UNDER
20KT TO PREVAIL THRU SAT.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...KC
LONG TERM...SRF
AVIATION...JLB
MARINE...KC
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
129 PM EDT TUE MAY 27 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 415 AM EDT TUE MAY 27 2014
00Z RAOBS/LATEST WV IMAGERY AND RUC ANALYSIS SHOW UPR RDG DOMINATING
THE NCENTRAL CONUS/CENTRAL CANADA BTWN TROFS OFF THE PAC NW AND THE
CNDN MARITIMES AND N OF CLOSED LO DRIFTING THRU THE SRN PLAINS. SFC
HI PRES OVER CENTRAL CANADA IS BLDG INTO NW ONTARIO...AND A N WIND
ON THE SRN FLANK OF THIS FEATURE IS ADVECTING DRIER LLVL AIR SHOWN
ON THE 00Z INL/YPL RAOBS INTO THE UPR LKS IN THE WAKE OF A SFC COLD
FROPA A BIT FASTER THAN MUCH OF THE GUIDANCE HAD INDICATED
PREVIOUSLY. WITH A NNE WIND CLOSE TO 15 MPH AT HOUGHTON...THE SFC
DEWPT FELL FM 56 AT 27/00Z TO 45 AT 27/05Z. THE 05Z SFC DEWPT
DEPRESSION WAS 14 DEGREES THERE. N WIND UP TO 24 KTS REPORTED AT
STANNARD ROCK LIGHTHOUSE HAS ENHANCED THIS LLVL DRYING TREND. THERE
WAS SOME FOG ON LK SUP EARLIER...BUT RECENT SHIP OBS/STLT IMAGERY
INDICATE PATCHY FOG LINGERS OVER PORTIONS OF ONLY ERN LK SUP. THE
LLVL DRYING HAS BEEN SLOWER TO DVLP OVER THE E AND SCENTRAL...AND
SOME LO CLDS AND FOG HAVE FORMED IN THESE AREAS. A NEARLY STNRY LINE
OF SHOWERS/SOME TS LINGERS FM SCENTRAL MN ACROSS NCENTRAL WI TO LK
MI JUST S OF MENOMINEE TO THE S OF THE SFC COLD FNT WHERE THE BULK
OF THE MODEL GUIDANCE SHOW SOME DEEP LYR QVECTOR CNVGC ASSOCIATED
WITH A WEAK SHRTWV MOVING W TO E THRU THE UPR MS RIVER VALLEY.
MAIN FCST CONCERNS IN THE SHORT TERM INVOLVE IMPACT OF CURRENT LLVL
DRYING TRENDS AND WHETHER ANY OF THE SHOWERS IN WI WL IMPACT THE SRN
COUNTIES TODAY.
TODAY...SHRTWV NOW OVER SCENTRAL MN INVIGORATING AREA OF SHOWERS TO
THE S OF UPR MI IS FCST TO DRIFT SLOWLY TO THE ESE THRU THE DAY AND
WEAKEN UNDER SLOW H5 RISES AS THE UPR RDG SLOWLY BUILDS INTO THE
CWA. ACCOMPANYING AREA OF QVECTOR CNVGC IS FCST TO FADE AWAY BY 18Z
AS A RESULT OF THE WEAKENING SHRTWV AND CONTINUED DRY ADVCTN ON THE
SRN FLANK OF THE HI PRES IN ONTARIO FCST TO BUILD INTO NCENTRAL LK
SUP THIS AFTN. CONSIDERING THE TRENDS AND THE STRONGER DRY ADVCTN
NOTED ABOVE...OPTED TO FOLLOW THE DRIER MODEL GUIDANCE ALIGNED
TOWARD THE 00Z GFS AND REMOVE POPS FM ALL BUT MENOMINEE COUNTY THIS
MRNG. IF THERE ARE ANY LO CLDS/FOG OVER MAINLY THE ERN CWA WHERE THE
LLVL DRYING HAS SO FAR BEEN MORE MARGINAL...THIS SHOULD DSPT WITH
CONTINUED DRY ADVECTION ON THE SRN FLANK OF BLDG HI PRES/DAYTIME
HEATING AND MIXING. MIXING TO H8 ON FCST SDNGS YIELDS HI TEMPS
APRCHG 80 OVER THE SCENTRAL FARTHER FM THE COOLING INFLUENCE OF LK
SUP. TEMPS NEAR THE BIG LK SHOULD HOLD IN THE 50S. DEEP MIXING OFF
THE DRIER GFS SDNGS WOULD INDICATE SFC DEWPTS COULD MIX OUT INTO THE
TEENS TODAY. GIVEN THE 00Z INL/YPL RAOBS...35 TO 45 FOR THE DEWPTS
SEEMS MORE RSNBL...RESULTING IN MIN RH FALLING AS LO AS 25 TO 30 PCT
BY LATE AFTN OVER THE INTERIOR W HALF.
TNGT...POCKET OF VERY DRY AIR IS FCST TO DROP INTO THE UPR LKS...
WITH H85-5 MEAN RH FALLING AS LO AS 20 PCT. PWAT FCST 0.33-0.50 INCH
WL BE 50-75 PCT OF NORMAL. WITH LGT WINDS/MOCLR SKIES UNDER SFC RDG
AXIS...OPTED TO TREND TOWARD THE LO END OF GUIDANCE FOR MIN TEMPS
FCST.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 329 AM EDT TUE MAY 27 2014
QUIET START TO THE LONG TERM WITH NO PRECIP EXPECTED FROM 12Z WED
THROUGH MOST OF SAT DUE TO HIGH PRESSURE AND DRY AIR OVERHEAD.
AN UPPER RIDGE WILL BUILD INTO THE CWA WED INTO SAT AS SFC RIDGING
REMAINS MOSTLY DOMINANT OVER THE CWA. THE AIRMASS WILL NOT CHANGE
MUCH ON WED AND THU WITH 850MB TEMPS GENERALLY OF 10-14C. THIS IS
EXPECTED TO RESULT IN HIGH TEMPS IN THE 70S TO LOW 80S INLAND...WITH
COOLER TEMPS IN THE 50S AND 60S RIGHT ALONG THE GREAT LAKES SHORES
DUE TO LAKE BREEZES.
STILL LOOKS LIKE A WEAK BACK DOOR COLD FRONT MAY MOVE INTO THE NERN
CWA ON FRI...WHICH MAY BRING TEMPS DOWN A BIT OVER THE NERN CWA.
WITH THE UPPER RIDGE BUILDING INTO THE WRN CWA...TEMPS SHOULD BE
WARMER THERE THAN ON WED-THU. THINK HIGHS IN THE UPPER 60S OVER THE
INTERIOR E AND IN THE LOW 80S INTERIOR W ARE REASONABLE...WITH
COOLER TEMPS NEAR THE GREAT LAKES SHORES.
THERE ARE STILL ISSUES WITH MODEL AGREEMENT ON THE TIMING OF
FEATURES OVER THE WEEKEND INTO EARLY NEXT WEEK...BUT THE GENERAL
SETUP IS AS FOLLOWS. THE UPPER RIDGE AXIS MOVES TO E OF THE CWA ON
SAT AS AN UPPER SHORTWAVE WILL MOVE TO NRN HUDSON BAY. THE SFC
TROUGH MOVING INTO MN BY 00Z SUN WILL LEAD TO INCREASED SLY FLOW.
850MB TEMPS ARE SHOWN BY MODELS TO INCREASE TO 17C BY 00Z SUN. HIGH
TEMPS IN THE MID 80S OVER THE INTERIOR CENTRAL AND W ARE CERTAINLY
NOT OUT OF THE QUESTION ON SAT. MODELS DO CONTINUE TO TREND SLOWER
ON THE PASSAGE OF THE SFC TROUGH/COLD FRONT...WHICH AT THIS POINT
APPEARS TO OCCUR SAT NIGHT AND/OR SUN. ADDITIONALLY...THE ECMWF IS
MORE PROGRESSIVE WITH THE FRONT WHILE THE GFS BRINGS SHORTWAVE
ENERGY UP THE FRONT AND STALLS IT OVER THE CWA INTO MON. SUN AND MON
ARE QUITE UNCERTAIN...BUT THE BEST CHANCE OF PRECIP IS IN THIS
PERIOD. WILL CONTINUE TO USE A CONSENSUS OF GUIDANCE...WITH CHANCE
POPS GIVEN UNCERTAINTY IN TIMING AND EXACT DETAILS.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON)
ISSUED AT 128 PM EDT TUE MAY 27 2014
EXPECT VFR CONDITIONS TO DOMINATE THIS FCST PERIOD WITH A DRY NE
FLOW ON THE SOUTHERN FLANK OF HIGH PRESSURE BUILDING FROM NRN
ONTARIO INTO THE WESTERN GREAT LAKES.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 415 AM EDT TUE MAY 27 2014
WITH RELATIVELY WEAK PRES GRADIENT TYPICAL OF THE WARM SEASON
DOMINATING THRU THIS FORECAST PERIOD...EXPECT WINDS MOSTLY UNDER
20KT TO PREVAIL THRU SAT.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...KC
LONG TERM...TITUS
AVIATION...JLB
MARINE...KC
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
727 AM EDT TUE MAY 27 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 415 AM EDT TUE MAY 27 2014
00Z RAOBS/LATEST WV IMAGERY AND RUC ANALYSIS SHOW UPR RDG DOMINATING
THE NCENTRAL CONUS/CENTRAL CANADA BTWN TROFS OFF THE PAC NW AND THE
CNDN MARITIMES AND N OF CLOSED LO DRIFTING THRU THE SRN PLAINS. SFC
HI PRES OVER CENTRAL CANADA IS BLDG INTO NW ONTARIO...AND A N WIND
ON THE SRN FLANK OF THIS FEATURE IS ADVECTING DRIER LLVL AIR SHOWN
ON THE 00Z INL/YPL RAOBS INTO THE UPR LKS IN THE WAKE OF A SFC COLD
FROPA A BIT FASTER THAN MUCH OF THE GUIDANCE HAD INDICATED
PREVIOUSLY. WITH A NNE WIND CLOSE TO 15 MPH AT HOUGHTON...THE SFC
DEWPT FELL FM 56 AT 27/00Z TO 45 AT 27/05Z. THE 05Z SFC DEWPT
DEPRESSION WAS 14 DEGREES THERE. N WIND UP TO 24 KTS REPORTED AT
STANNARD ROCK LIGHTHOUSE HAS ENHANCED THIS LLVL DRYING TREND. THERE
WAS SOME FOG ON LK SUP EARLIER...BUT RECENT SHIP OBS/STLT IMAGERY
INDICATE PATCHY FOG LINGERS OVER PORTIONS OF ONLY ERN LK SUP. THE
LLVL DRYING HAS BEEN SLOWER TO DVLP OVER THE E AND SCENTRAL...AND
SOME LO CLDS AND FOG HAVE FORMED IN THESE AREAS. A NEARLY STNRY LINE
OF SHOWERS/SOME TS LINGERS FM SCENTRAL MN ACROSS NCENTRAL WI TO LK
MI JUST S OF MENOMINEE TO THE S OF THE SFC COLD FNT WHERE THE BULK
OF THE MODEL GUIDANCE SHOW SOME DEEP LYR QVECTOR CNVGC ASSOCIATED
WITH A WEAK SHRTWV MOVING W TO E THRU THE UPR MS RIVER VALLEY.
MAIN FCST CONCERNS IN THE SHORT TERM INVOLVE IMPACT OF CURRENT LLVL
DRYING TRENDS AND WHETHER ANY OF THE SHOWERS IN WI WL IMPACT THE SRN
COUNTIES TODAY.
TODAY...SHRTWV NOW OVER SCENTRAL MN INVIGORATING AREA OF SHOWERS TO
THE S OF UPR MI IS FCST TO DRIFT SLOWLY TO THE ESE THRU THE DAY AND
WEAKEN UNDER SLOW H5 RISES AS THE UPR RDG SLOWLY BUILDS INTO THE
CWA. ACCOMPANYING AREA OF QVECTOR CNVGC IS FCST TO FADE AWAY BY 18Z
AS A RESULT OF THE WEAKENING SHRTWV AND CONTINUED DRY ADVCTN ON THE
SRN FLANK OF THE HI PRES IN ONTARIO FCST TO BUILD INTO NCENTRAL LK
SUP THIS AFTN. CONSIDERING THE TRENDS AND THE STRONGER DRY ADVCTN
NOTED ABOVE...OPTED TO FOLLOW THE DRIER MODEL GUIDANCE ALIGNED
TOWARD THE 00Z GFS AND REMOVE POPS FM ALL BUT MENOMINEE COUNTY THIS
MRNG. IF THERE ARE ANY LO CLDS/FOG OVER MAINLY THE ERN CWA WHERE THE
LLVL DRYING HAS SO FAR BEEN MORE MARGINAL...THIS SHOULD DSPT WITH
CONTINUED DRY ADVECTION ON THE SRN FLANK OF BLDG HI PRES/DAYTIME
HEATING AND MIXING. MIXING TO H8 ON FCST SDNGS YIELDS HI TEMPS
APRCHG 80 OVER THE SCENTRAL FARTHER FM THE COOLING INFLUENCE OF LK
SUP. TEMPS NEAR THE BIG LK SHOULD HOLD IN THE 50S. DEEP MIXING OFF
THE DRIER GFS SDNGS WOULD INDICATE SFC DEWPTS COULD MIX OUT INTO THE
TEENS TODAY. GIVEN THE 00Z INL/YPL RAOBS...35 TO 45 FOR THE DEWPTS
SEEMS MORE RSNBL...RESULTING IN MIN RH FALLING AS LO AS 25 TO 30 PCT
BY LATE AFTN OVER THE INTERIOR W HALF.
TNGT...POCKET OF VERY DRY AIR IS FCST TO DROP INTO THE UPR LKS...
WITH H85-5 MEAN RH FALLING AS LO AS 20 PCT. PWAT FCST 0.33-0.50 INCH
WL BE 50-75 PCT OF NORMAL. WITH LGT WINDS/MOCLR SKIES UNDER SFC RDG
AXIS...OPTED TO TREND TOWARD THE LO END OF GUIDANCE FOR MIN TEMPS
FCST.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 329 AM EDT TUE MAY 27 2014
QUIET START TO THE LONG TERM WITH NO PRECIP EXPECTED FROM 12Z WED
THROUGH MOST OF SAT DUE TO HIGH PRESSURE AND DRY AIR OVERHEAD.
AN UPPER RIDGE WILL BUILD INTO THE CWA WED INTO SAT AS SFC RIDGING
REMAINS MOSTLY DOMINANT OVER THE CWA. THE AIRMASS WILL NOT CHANGE
MUCH ON WED AND THU WITH 850MB TEMPS GENERALLY OF 10-14C. THIS IS
EXPECTED TO RESULT IN HIGH TEMPS IN THE 70S TO LOW 80S INLAND...WITH
COOLER TEMPS IN THE 50S AND 60S RIGHT ALONG THE GREAT LAKES SHORES
DUE TO LAKE BREEZES.
STILL LOOKS LIKE A WEAK BACK DOOR COLD FRONT MAY MOVE INTO THE NERN
CWA ON FRI...WHICH MAY BRING TEMPS DOWN A BIT OVER THE NERN CWA.
WITH THE UPPER RIDGE BUILDING INTO THE WRN CWA...TEMPS SHOULD BE
WARMER THERE THAN ON WED-THU. THINK HIGHS IN THE UPPER 60S OVER THE
INTERIOR E AND IN THE LOW 80S INTERIOR W ARE REASONABLE...WITH
COOLER TEMPS NEAR THE GREAT LAKES SHORES.
THERE ARE STILL ISSUES WITH MODEL AGREEMENT ON THE TIMING OF
FEATURES OVER THE WEEKEND INTO EARLY NEXT WEEK...BUT THE GENERAL
SETUP IS AS FOLLOWS. THE UPPER RIDGE AXIS MOVES TO E OF THE CWA ON
SAT AS AN UPPER SHORTWAVE WILL MOVE TO NRN HUDSON BAY. THE SFC
TROUGH MOVING INTO MN BY 00Z SUN WILL LEAD TO INCREASED SLY FLOW.
850MB TEMPS ARE SHOWN BY MODELS TO INCREASE TO 17C BY 00Z SUN. HIGH
TEMPS IN THE MID 80S OVER THE INTERIOR CENTRAL AND W ARE CERTAINLY
NOT OUT OF THE QUESTION ON SAT. MODELS DO CONTINUE TO TREND SLOWER
ON THE PASSAGE OF THE SFC TROUGH/COLD FRONT...WHICH AT THIS POINT
APPEARS TO OCCUR SAT NIGHT AND/OR SUN. ADDITIONALLY...THE ECMWF IS
MORE PROGRESSIVE WITH THE FRONT WHILE THE GFS BRINGS SHORTWAVE
ENERGY UP THE FRONT AND STALLS IT OVER THE CWA INTO MON. SUN AND MON
ARE QUITE UNCERTAIN...BUT THE BEST CHANCE OF PRECIP IS IN THIS
PERIOD. WILL CONTINUE TO USE A CONSENSUS OF GUIDANCE...WITH CHANCE
POPS GIVEN UNCERTAINTY IN TIMING AND EXACT DETAILS.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z WEDNESDAY MORNING)
ISSUED AT 726 AM EDT TUE MAY 27 2014
EXPECT VFR CONDITIONS TO DOMINATE THIS FCST PERIOD WITH A DRY NNE
FLOW ON THE SRN FLANK OF HI PRES BLDG FM ONTARIO TOWARD LK SUPERIOR.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 415 AM EDT TUE MAY 27 2014
WITH RELATIVELY WEAK PRES GRADIENT TYPICAL OF THE WARM SEASON
DOMINATING THRU THIS FORECAST PERIOD...EXPECT WINDS MOSTLY UNDER
20KT TO PREVAIL THRU SAT.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...KC
LONG TERM...TITUS
AVIATION...KC
MARINE...KC
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
504 AM EDT TUE MAY 27 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 415 AM EDT TUE MAY 27 2014
00Z RAOBS/LATEST WV IMAGERY AND RUC ANALYSIS SHOW UPR RDG DOMINATING
THE NCENTRAL CONUS/CENTRAL CANADA BTWN TROFS OFF THE PAC NW AND THE
CNDN MARITIMES AND N OF CLOSED LO DRIFTING THRU THE SRN PLAINS. SFC
HI PRES OVER CENTRAL CANADA IS BLDG INTO NW ONTARIO...AND A N WIND
ON THE SRN FLANK OF THIS FEATURE IS ADVECTING DRIER LLVL AIR SHOWN
ON THE 00Z INL/YPL RAOBS INTO THE UPR LKS IN THE WAKE OF A SFC COLD
FROPA A BIT FASTER THAN MUCH OF THE GUIDANCE HAD INDICATED
PREVIOUSLY. WITH A NNE WIND CLOSE TO 15 MPH AT HOUGHTON...THE SFC
DEWPT FELL FM 56 AT 27/00Z TO 45 AT 27/05Z. THE 05Z SFC DEWPT
DEPRESSION WAS 14 DEGREES THERE. N WIND UP TO 24 KTS REPORTED AT
STANNARD ROCK LIGHTHOUSE HAS ENHANCED THIS LLVL DRYING TREND. THERE
WAS SOME FOG ON LK SUP EARLIER...BUT RECENT SHIP OBS/STLT IMAGERY
INDICATE PATCHY FOG LINGERS OVER PORTIONS OF ONLY ERN LK SUP. THE
LLVL DRYING HAS BEEN SLOWER TO DVLP OVER THE E AND SCENTRAL...AND
SOME LO CLDS AND FOG HAVE FORMED IN THESE AREAS. A NEARLY STNRY LINE
OF SHOWERS/SOME TS LINGERS FM SCENTRAL MN ACROSS NCENTRAL WI TO LK
MI JUST S OF MENOMINEE TO THE S OF THE SFC COLD FNT WHERE THE BULK
OF THE MODEL GUIDANCE SHOW SOME DEEP LYR QVECTOR CNVGC ASSOCIATED
WITH A WEAK SHRTWV MOVING W TO E THRU THE UPR MS RIVER VALLEY.
MAIN FCST CONCERNS IN THE SHORT TERM INVOLVE IMPACT OF CURRENT LLVL
DRYING TRENDS AND WHETHER ANY OF THE SHOWERS IN WI WL IMPACT THE SRN
COUNTIES TODAY.
TODAY...SHRTWV NOW OVER SCENTRAL MN INVIGORATING AREA OF SHOWERS TO
THE S OF UPR MI IS FCST TO DRIFT SLOWLY TO THE ESE THRU THE DAY AND
WEAKEN UNDER SLOW H5 RISES AS THE UPR RDG SLOWLY BUILDS INTO THE
CWA. ACCOMPANYING AREA OF QVECTOR CNVGC IS FCST TO FADE AWAY BY 18Z
AS A RESULT OF THE WEAKENING SHRTWV AND CONTINUED DRY ADVCTN ON THE
SRN FLANK OF THE HI PRES IN ONTARIO FCST TO BUILD INTO NCENTRAL LK
SUP THIS AFTN. CONSIDERING THE TRENDS AND THE STRONGER DRY ADVCTN
NOTED ABOVE...OPTED TO FOLLOW THE DRIER MODEL GUIDANCE ALIGNED
TOWARD THE 00Z GFS AND REMOVE POPS FM ALL BUT MENOMINEE COUNTY THIS
MRNG. IF THERE ARE ANY LO CLDS/FOG OVER MAINLY THE ERN CWA WHERE THE
LLVL DRYING HAS SO FAR BEEN MORE MARGINAL...THIS SHOULD DSPT WITH
CONTINUED DRY ADVECTION ON THE SRN FLANK OF BLDG HI PRES/DAYTIME
HEATING AND MIXING. MIXING TO H8 ON FCST SDNGS YIELDS HI TEMPS
APRCHG 80 OVER THE SCENTRAL FARTHER FM THE COOLING INFLUENCE OF LK
SUP. TEMPS NEAR THE BIG LK SHOULD HOLD IN THE 50S. DEEP MIXING OFF
THE DRIER GFS SDNGS WOULD INDICATE SFC DEWPTS COULD MIX OUT INTO THE
TEENS TODAY. GIVEN THE 00Z INL/YPL RAOBS...35 TO 45 FOR THE DEWPTS
SEEMS MORE RSNBL...RESULTING IN MIN RH FALLING AS LO AS 25 TO 30 PCT
BY LATE AFTN OVER THE INTERIOR W HALF.
TNGT...POCKET OF VERY DRY AIR IS FCST TO DROP INTO THE UPR LKS...
WITH H85-5 MEAN RH FALLING AS LO AS 20 PCT. PWAT FCST 0.33-0.50 INCH
WL BE 50-75 PCT OF NORMAL. WITH LGT WINDS/MOCLR SKIES UNDER SFC RDG
AXIS...OPTED TO TREND TOWARD THE LO END OF GUIDANCE FOR MIN TEMPS
FCST.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 329 AM EDT TUE MAY 27 2014
QUIET START TO THE LONG TERM WITH NO PRECIP EXPECTED FROM 12Z WED
THROUGH MOST OF SAT DUE TO HIGH PRESSURE AND DRY AIR OVERHEAD.
AN UPPER RIDGE WILL BUILD INTO THE CWA WED INTO SAT AS SFC RIDGING
REMAINS MOSTLY DOMINANT OVER THE CWA. THE AIRMASS WILL NOT CHANGE
MUCH ON WED AND THU WITH 850MB TEMPS GENERALLY OF 10-14C. THIS IS
EXPECTED TO RESULT IN HIGH TEMPS IN THE 70S TO LOW 80S INLAND...WITH
COOLER TEMPS IN THE 50S AND 60S RIGHT ALONG THE GREAT LAKES SHORES
DUE TO LAKE BREEZES.
STILL LOOKS LIKE A WEAK BACK DOOR COLD FRONT MAY MOVE INTO THE NERN
CWA ON FRI...WHICH MAY BRING TEMPS DOWN A BIT OVER THE NERN CWA.
WITH THE UPPER RIDGE BUILDING INTO THE WRN CWA...TEMPS SHOULD BE
WARMER THERE THAN ON WED-THU. THINK HIGHS IN THE UPPER 60S OVER THE
INTERIOR E AND IN THE LOW 80S INTERIOR W ARE REASONABLE...WITH
COOLER TEMPS NEAR THE GREAT LAKES SHORES.
THERE ARE STILL ISSUES WITH MODEL AGREEMENT ON THE TIMING OF
FEATURES OVER THE WEEKEND INTO EARLY NEXT WEEK...BUT THE GENERAL
SETUP IS AS FOLLOWS. THE UPPER RIDGE AXIS MOVES TO E OF THE CWA ON
SAT AS AN UPPER SHORTWAVE WILL MOVE TO NRN HUDSON BAY. THE SFC
TROUGH MOVING INTO MN BY 00Z SUN WILL LEAD TO INCREASED SLY FLOW.
850MB TEMPS ARE SHOWN BY MODELS TO INCREASE TO 17C BY 00Z SUN. HIGH
TEMPS IN THE MID 80S OVER THE INTERIOR CENTRAL AND W ARE CERTAINLY
NOT OUT OF THE QUESTION ON SAT. MODELS DO CONTINUE TO TREND SLOWER
ON THE PASSAGE OF THE SFC TROUGH/COLD FRONT...WHICH AT THIS POINT
APPEARS TO OCCUR SAT NIGHT AND/OR SUN. ADDITIONALLY...THE ECMWF IS
MORE PROGRESSIVE WITH THE FRONT WHILE THE GFS BRINGS SHORTWAVE
ENERGY UP THE FRONT AND STALLS IT OVER THE CWA INTO MON. SUN AND MON
ARE QUITE UNCERTAIN...BUT THE BEST CHANCE OF PRECIP IS IN THIS
PERIOD. WILL CONTINUE TO USE A CONSENSUS OF GUIDANCE...WITH CHANCE
POPS GIVEN UNCERTAINTY IN TIMING AND EXACT DETAILS.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT)
ISSUED AT 137 AM EDT TUE MAY 27 2014
THE N WIND BEHIND A COLD FRONT PASSING THRU THE AREA EARLY THIS MRNG
WL BRING THE POTENTIAL FOR SOME LO CLDS/IFR CIGS AT MAINLY SAW...
WHERE THIS WIND PRESENTS A SHARPER UPSLOPE WIND COMPONENT. BUT THE
MAGNITUDE OF RECENT DRYING AT IWD AND ESPECIALLY CMX INDICATES
CONDITIONS LOWER THAN VFR ARE NOT LIKELY. IF THE MORE AGGRESSIVE
LLVL DRYING CONTINUES...THE LO CLDS FCST AT SAW MAY NOT MATERIALIZE.
ANY LO CLDS/FOG THAT FORM WL DSPT LATER THIS MORNING AS CONTINUED DRY
ADVECTION TO THE S OF BLDG HI PRES IN ONTARIO AND HIGH LATE MAY SUN
ANGLE DRY THE LLVLS.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 415 AM EDT TUE MAY 27 2014
WITH RELATIVELY WEAK PRES GRADIENT TYPICAL OF THE WARM SEASON
DOMINATING THRU THIS FORECAST PERIOD...EXPECT WINDS MOSTLY UNDER
20KT TO PREVAIL THRU SAT.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...KC
LONG TERM...TITUS
AVIATION...KC
MARINE...KC
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
433 AM EDT TUE MAY 27 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 415 AM EDT TUE MAY 27 2014
00Z RAOBS/LATEST WV IMAGERY AND RUC ANALYSIS SHOW UPR RDG DOMINATING
THE NCENTRAL CONUS/CENTRAL CANADA BTWN TROFS OFF THE PAC NW AND THE
CNDN MARITIMES AND N OF CLOSED LO DRIFTING THRU THE SRN PLAINS. SFC
HI PRES OVER CENTRAL CANADA IS BLDG INTO NW ONTARIO...AND A N WIND
ON THE SRN FLANK OF THIS FEATURE IS ADVECTING DRIER LLVL AIR SHOWN
ON THE 00Z INL/YPL RAOBS INTO THE UPR LKS IN THE WAKE OF A SFC COLD
FROPA A BIT FASTER THAN MUCH OF THE GUIDANCE HAD INDICATED
PREVIOUSLY. WITH A NNE WIND CLOSE TO 15 MPH AT HOUGHTON...THE SFC
DEWPT FELL FM 56 AT 27/00Z TO 45 AT 27/05Z. THE 05Z SFC DEWPT
DEPRESSION WAS 14 DEGREES THERE. N WIND UP TO 24 KTS REPORTED AT
STANNARD ROCK LIGHTHOUSE HAS ENHANCED THIS LLVL DRYING TREND. THERE
WAS SOME FOG ON LK SUP EARLIER...BUT RECENT SHIP OBS/STLT IMAGERY
INDICATE PATCHY FOG LINGERS OVER PORTIONS OF ONLY ERN LK SUP. THE
LLVL DRYING HAS BEEN SLOWER TO DVLP OVER THE E AND SCENTRAL...AND
SOME LO CLDS AND FOG HAVE FORMED IN THESE AREAS. A NEARLY STNRY LINE
OF SHOWERS/SOME TS LINGERS FM SCENTRAL MN ACROSS NCENTRAL WI TO LK
MI JUST S OF MENOMINEE TO THE S OF THE SFC COLD FNT WHERE THE BULK
OF THE MODEL GUIDANCE SHOW SOME DEEP LYR QVECTOR CNVGC ASSOCIATED
WITH A WEAK SHRTWV MOVING W TO E THRU THE UPR MS RIVER VALLEY.
MAIN FCST CONCERNS IN THE SHORT TERM INVOLVE IMPACT OF CURRENT LLVL
DRYING TRENDS AND WHETHER ANY OF THE SHOWERS IN WI WL IMPACT THE SRN
COUNTIES TODAY.
TODAY...SHRTWV NOW OVER SCENTRAL MN INVIGORATING AREA OF SHOWERS TO
THE S OF UPR MI IS FCST TO DRIFT SLOWLY TO THE ESE THRU THE DAY AND
WEAKEN UNDER SLOW H5 RISES AS THE UPR RDG SLOWLY BUILDS INTO THE
CWA. ACCOMPANYING AREA OF QVECTOR CNVGC IS FCST TO FADE AWAY BY 18Z
AS A RESULT OF THE WEAKENING SHRTWV AND CONTINUED DRY ADVCTN ON THE
SRN FLANK OF THE HI PRES IN ONTARIO FCST TO BUILD INTO NCENTRAL LK
SUP THIS AFTN. CONSIDERING THE TRENDS AND THE STRONGER DRY ADVCTN
NOTED ABOVE...OPTED TO FOLLOW THE DRIER MODEL GUIDANCE ALIGNED
TOWARD THE 00Z GFS AND REMOVE POPS FM ALL BUT MENOMINEE COUNTY THIS
MRNG. IF THERE ARE ANY LO CLDS/FOG OVER MAINLY THE ERN CWA WHERE THE
LLVL DRYING HAS SO FAR BEEN MORE MARGINAL...THIS SHOULD DSPT WITH
CONTINUED DRY ADVECTION ON THE SRN FLANK OF BLDG HI PRES/DAYTIME
HEATING AND MIXING. MIXING TO H8 ON FCST SDNGS YIELDS HI TEMPS
APRCHG 80 OVER THE SCENTRAL FARTHER FM THE COOLING INFLUENCE OF LK
SUP. TEMPS NEAR THE BIG LK SHOULD HOLD IN THE 50S. DEEP MIXING OFF
THE DRIER GFS SDNGS WOULD INDICATE SFC DEWPTS COULD MIX OUT INTO THE
TEENS TODAY. GIVEN THE 00Z INL/YPL RAOBS...35 TO 45 FOR THE DEWPTS
SEEMS MORE RSNBL...RESULTING IN MIN RH FALLING AS LO AS 25 TO 30 PCT
BY LATE AFTN OVER THE INTERIOR W HALF.
TNGT...POCKET OF VERY DRY AIR IS FCST TO DROP INTO THE UPR LKS...
WITH H85-5 MEAN RH FALLING AS LO AS 20 PCT. PWAT FCST 0.33-0.50 INCH
WL BE 50-75 PCT OF NORMAL. WITH LGT WINDS/MOCLR SKIES UNDER SFC RDG
AXIS...OPTED TO TREND TOWARD THE LO END OF GUIDANCE FOR MIN TEMPS
FCST.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 329 AM EDT TUE MAY 27 2014
QUIET START TO THE LONG TERM WITH NO PRECIP EXPECTED FROM 12Z WED
THROUGH MOST OF SAT DUE TO HIGH PRESSURE AND DRY AIR OVERHEAD.
AN UPPER RIDGE WILL BUILD INTO THE CWA WED INTO SAT AS SFC RIDGING
REMAINS MOSTLY DOMINANT OVER THE CWA. THE AIRMASS WILL NOT CHANGE
MUCH ON WED AND THU WITH 850MB TEMPS GENERALLY OF 10-14C. THIS IS
EXPECTED TO RESULT IN HIGH TEMPS IN THE 70S TO LOW 80S INLAND...WITH
COOLER TEMPS IN THE 50S AND 60S RIGHT ALONG THE GREAT LAKES SHORES
DUE TO LAKE BREEZES.
STILL LOOKS LIKE A WEAK BACK DOOR COLD FRONT MAY MOVE INTO THE NERN
CWA ON FRI...WHICH MAY BRING TEMPS DOWN A BIT OVER THE NERN CWA.
WITH THE UPPER RIDGE BUILDING INTO THE WRN CWA...TEMPS SHOULD BE
WARMER THERE THAN ON WED-THU. THINK HIGHS IN THE UPPER 60S OVER THE
INTERIOR E AND IN THE LOW 80S INTERIOR W ARE REASONABLE...WITH
COOLER TEMPS NEAR THE GREAT LAKES SHORES.
THERE ARE STILL ISSUES WITH MODEL AGREEMENT ON THE TIMING OF
FEATURES OVER THE WEEKEND INTO EARLY NEXT WEEK...BUT THE GENERAL
SETUP IS AS FOLLOWS. THE UPPER RIDGE AXIS MOVES TO E OF THE CWA ON
SAT AS AN UPPER SHORTWAVE WILL MOVE TO NRN HUDSON BAY. THE SFC
TROUGH MOVING INTO MN BY 00Z SUN WILL LEAD TO INCREASED SLY FLOW.
850MB TEMPS ARE SHOWN BY MODELS TO INCREASE TO 17C BY 00Z SUN. HIGH
TEMPS IN THE MID 80S OVER THE INTERIOR CENTRAL AND W ARE CERTAINLY
NOT OUT OF THE QUESTION ON SAT. MODELS DO CONTINUE TO TREND SLOWER
ON THE PASSAGE OF THE SFC TROUGH/COLD FRONT...WHICH AT THIS POINT
APPEARS TO OCCUR SAT NIGHT AND/OR SUN. ADDITIONALLY...THE ECMWF IS
MORE PROGRESSIVE WITH THE FRONT WHILE THE GFS BRINGS SHORTWAVE
ENERGY UP THE FRONT AND STALLS IT OVER THE CWA INTO MON. SUN AND MON
ARE QUITE UNCERTAIN...BUT THE BEST CHANCE OF PRECIP IS IN THIS
PERIOD. WILL CONTINUE TO USE A CONSENSUS OF GUIDANCE...WITH CHANCE
POPS GIVEN UNCERTAINTY IN TIMING AND EXACT DETAILS.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT)
ISSUED AT 137 AM EDT TUE MAY 27 2014
THE N WIND BEHIND A COLD FRONT PASSING THRU THE AREA EARLY THIS MRNG
WL BRING THE POTENTIAL FOR SOME LO CLDS/IFR CIGS AT MAINLY SAW...
WHERE THIS WIND PRESENTS A SHARPER UPSLOPE WIND COMPONENT. BUT THE
MAGNITUDE OF RECENT DRYING AT IWD AND ESPECIALLY CMX INDICATES
CONDITIONS LOWER THAN VFR ARE NOT LIKELY. IF THE MORE AGGRESSIVE
LLVL DRYING CONTINUES...THE LO CLDS FCST AT SAW MAY NOT MATERIALIZE.
ANY LO CLDS/FOG THAT FORM WL DSPT LATER THIS MORNING AS CONTINUED DRY
ADVECTION TO THE S OF BLDG HI PRES IN ONTARIO AND HIGH LATE MAY SUN
ANGLE DRY THE LLVLS.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 415 AM EDT TUE MAY 27 2014
WITH RELATIVELY WEAK PRES GRADIENT TYPICAL OF THE WARM SEASON
DOMINATING THRU THIS FORECAST PERIOD...EXPECT WINDS MOSTLY UNDER
20KT TO PREVAIL THRU SAT.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
DENSE FOG ADVISORY UNTIL 8 AM EDT THIS MORNING FOR LMZ248-250.
&&
$$
SHORT TERM...KC
LONG TERM...TITUS
AVIATION...KC
MARINE...KC
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
331 AM EDT TUE MAY 27 2014
.SHORT TERM...(THIS EVENING THROUGH TUESDAY)
ISSUED AT 511 PM EDT MON MAY 26 2014
WATER VAPOR IMAGERY AND RUC ANALYSIS SHOW A BROAD RIDGE OVER CNTRL
NAMERICA. VIGOROUS LOOKING SHORTWAVE HAS ROUNDED THE RIDGE AND IS
MOVING ACROSS FAR NRN ONTARIO...TOO FAR N TO HAVE MUCH IF ANY IMPACT
FORCING-WISE ACROSS UPPER MI AS 500MB HEIGHTS ARE RISING SLIGHTLY
THIS AFTN. AT THE SFC...ASSOCIATED COLD FRONT APPEARS TO BE DRIFTING
ACROSS WRN LAKE SUPERIOR...BUT LAKE BREEZE DEVELOPMENT IS MAKING
IT DIFFICULT TO DETERMINE EXACT LOCATION OVER THE UPPER LAKES. AS
EXPECTED...CONSIDERABLE MOISTENING OF THE AIR MASS HAS OCCURRED OVER
THE LAST 12 TO 18HRS. 00Z KGRB SOUNDING SHOWED PRECIPITABLE WATER AT
0.5 INCHES/72PCT OF NORMAL WHILE 12Z SOUNDING SHOWED 1.45
INCHES/208PCT OF NORMAL. AS A RESULT...MORNING SUNSHINE LED TO QUICK
CU DEVELOPMENT THIS MORNING...AND NOW SCT SHRA AND ISOLD TSRA ARE
OCCURRING OVER MAINLY THE INTERIOR W 2/3RDS OF UPPER MI. LATEST SPC
MESOANALYIS SHOWS MLCAPES IN THE 500-1000J/KG RANGE. WEAK SHEAR
MOSTLY UNDER 20KT IS KEEPING STORMS IN CHECK. LOCALLY HIGHER DEEP
LAYER SHEAR CLOSER TO 30KT HAS LED TO A FEW STRONG STORMS IN NE WI
TO THE W AND NW OF KMNM. STORMS THERE HAVE BEEN SHOWING BRIEF
CIRCULATION AND HAIL SIGNATURES. UPSTREAM...BEHIND COLD FRONT...
CONSIDERABLE STRATUS AND FOG WAS OBSERVED EARLY THIS MORNING ACROSS
NW MN INTO NRN ONTARIO. WITH HIGH LATE MAY SUN ANGLE...THE
STRATUS/FOG HAS COMPLETELY MIXED OUT THIS AFTN. MEANWHILE...SHRA
THAT MOVED ACROSS LAKE MICHIGAN THIS MORNING HELPED GENERATE FOG
THAT HAS QUICKLY ADVECTED N TO THE UPPER MI SHORELINE. PER SATELLITE
IMAGERY AND WEBCAMS...FOG IS ALSO DEVELOPING OVER W AND CNTRL LAKE
SUPERIOR...APPARENTLY ALONG THE FRONTAL CONVERGENCE ZONE.
WITH ONGOING CONVECTION SOLELY EXISTING BECAUSE OF DAYTIME HEATING
AND RESULTING INSTABILITY...EXPECT SHRA/TSRA TO GRADUALLY END FROM N
TO S THIS EVENING. HOWEVER...THERE ARE INDICATIONS OF A WEAK
SHORTWAVE DRIFTING E FROM MN...AND MODELS INDICATE WEAK DEEP LAYER
QVECTOR CONVERGENCE SHIFTING ACROSS NRN WI/ADJACENT UPPER MI. IN
LIGHT OF THIS...WILL MAINTAIN SCHC POPS ACROSS THE WI/MI BORDER INTO
SCNTRL UPPER MI THRU THE NIGHT. OTHER ISSUE TONIGHT IS POTENTIAL OF
FOG/LOW CLOUDS AND PERHAPS SOME -DZ NEAR LAKE SUPERIOR. THE
DEVELOPMENT OF SOME FOG TODAY ON LAKE SUPERIOR GREATLY INCREASES THE
POTENTIAL FOR FOG/DZ NEAR THE LAKE WHERE WINDS SHIFT MORE DIRECTLY
ONSHORE WITH PASSAGE OF WEAK COLD FRONT DURING THE NIGHT. THUS...
FCST WILL REFLECT SOME FOG DEVELOPMENT NEAR LAKE SUPERIOR WITH BEST
CHC OF LOWER VIS AND -DZ OVER NCNTRL UPPER MI LATE TONIGHT INTO TUE
MORNING AS FLOW BECOME MORE SHARPLY UPSLOPE IN THAT AREA.
ANY MORNING FOG/LOW CLOUDS/-DZ NEAR LAKE SUPERIOR WILL GIVE WAY TO
SUNNY SKIES DURING THE AFTN AS DRIER AIR SPREADS S IN ASSOCIATION
WITH HUDSON BAY HIGH PRES RIDGE BUILDING SOUTHWARD INTO THE UPPER
LAKES. KEPT A SCHC MENTION OF -SHRA ALONG MI/WI BORDER INTO THE MID
AFTN HRS UNTIL DRIER AIR MAKES A STRONGER PRESENCE AS SFC BOUNDARY
CONTINUES TO DRIFT FARTHER S. IT WILL BE CONSIDERABLY COOLER NEAR
LAKE SUPERIOR ON TUE COMPARED TO TODAY UNDER NORTHERLY WIND ENHANCED
BY LAKE BREEZE COMPONENT. MANY LAKESIDE LOCATIONS WILL NOT GET OUT
OF THE 50S AND SOME MAY SPEND MUCH OF THE DAY IN THE 40S. ACROSS THE
S...MIXING TOWARD 800MB ON FCST SOUNDINGS SUGGESTS HIGHS WILL REACH
WELL INTO THE 70S.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 329 AM EDT TUE MAY 27 2014
QUIET START TO THE LONG TERM WITH NO PRECIP EXPECTED FROM 12Z WED
THROUGH MOST OF SAT DUE TO HIGH PRESSURE AND DRY AIR OVERHEAD.
AN UPPER RIDGE WILL BUILD INTO THE CWA WED INTO SAT AS SFC RIDGING
REMAINS MOSTLY DOMINANT OVER THE CWA. THE AIRMASS WILL NOT CHANGE
MUCH ON WED AND THU WITH 850MB TEMPS GENERALLY OF 10-14C. THIS IS
EXPECTED TO RESULT IN HIGH TEMPS IN THE 70S TO LOW 80S INLAND...WITH
COOLER TEMPS IN THE 50S AND 60S RIGHT ALONG THE GREAT LAKES SHORES
DUE TO LAKE BREEZES.
STILL LOOKS LIKE A WEAK BACK DOOR COLD FRONT MAY MOVE INTO THE NERN
CWA ON FRI...WHICH MAY BRING TEMPS DOWN A BIT OVER THE NERN CWA.
WITH THE UPPER RIDGE BUILDING INTO THE WRN CWA...TEMPS SHOULD BE
WARMER THERE THAN ON WED-THU. THINK HIGHS IN THE UPPER 60S OVER THE
INTERIOR E AND IN THE LOW 80S INTERIOR W ARE REASONABLE...WITH
COOLER TEMPS NEAR THE GREAT LAKES SHORES.
THERE ARE STILL ISSUES WITH MODEL AGREEMENT ON THE TIMING OF
FEATURES OVER THE WEEKEND INTO EARLY NEXT WEEK...BUT THE GENERAL
SETUP IS AS FOLLOWS. THE UPPER RIDGE AXIS MOVES TO E OF THE CWA ON
SAT AS AN UPPER SHORTWAVE WILL MOVE TO NRN HUDSON BAY. THE SFC
TROUGH MOVING INTO MN BY 00Z SUN WILL LEAD TO INCREASED SLY FLOW.
850MB TEMPS ARE SHOWN BY MODELS TO INCREASE TO 17C BY 00Z SUN. HIGH
TEMPS IN THE MID 80S OVER THE INTERIOR CENTRAL AND W ARE CERTAINLY
NOT OUT OF THE QUESTION ON SAT. MODELS DO CONTINUE TO TREND SLOWER
ON THE PASSAGE OF THE SFC TROUGH/COLD FRONT...WHICH AT THIS POINT
APPEARS TO OCCUR SAT NIGHT AND/OR SUN. ADDITIONALLY...THE ECMWF IS
MORE PROGRESSIVE WITH THE FRONT WHILE THE GFS BRINGS SHORTWAVE
ENERGY UP THE FRONT AND STALLS IT OVER THE CWA INTO MON. SUN AND MON
ARE QUITE UNCERTAIN...BUT THE BEST CHANCE OF PRECIP IS IN THIS
PERIOD. WILL CONTINUE TO USE A CONSENSUS OF GUIDANCE...WITH CHANCE
POPS GIVEN UNCERTAINTY IN TIMING AND EXACT DETAILS.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT)
ISSUED AT 137 AM EDT TUE MAY 27 2014
THE N WIND BEHIND A COLD FRONT PASSING THRU THE AREA EARLY THIS MRNG
WL BRING THE POTENTIAL FOR SOME LO CLDS/IFR CIGS AT MAINLY SAW...
WHERE THIS WIND PRESENTS A SHARPER UPSLOPE WIND COMPONENT. BUT THE
MAGNITUDE OF RECENT DRYING AT IWD AND ESPECIALLY CMX INDICATES
CONDITIONS LOWER THAN VFR ARE NOT LIKELY. IF THE MORE AGGRESSIVE
LLVL DRYING CONTINUES...THE LO CLDS FCST AT SAW MAY NOT MATERIALIZE.
ANY LO CLDS/FOG THAT FORM WL DSPT LATER THIS MORNING AS CONTINUED DRY
ADVECTION TO THE S OF BLDG HI PRES IN ONTARIO AND HIGH LATE MAY SUN
ANGLE DRY THE LLVLS.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 511 PM EDT MON MAY 26 2014
WITH RELATIVELY WEAK PRES GRADIENT TYPICAL OF THE WARM SEASON
DOMINATING THRU THIS FORECAST PERIOD...EXPECT WINDS MOSTLY UNDER
20KT TO PREVAIL. IN THE NEAR TERM...FOG THAT HAS DEVELOPED OVER
PORTIONS OF W AND CNTRL LAKE SUPERIOR WILL SPREAD S TO THE UPPER
MI SHORE TONIGHT AS COLD FRONT DRIFTS S INTO UPPER MI. THIS FOG
SHOULD DISSIPATE TUE MORNING AS WINDS BECOME MORE ANTICYCLONIC AND
DRIER AIR ADVECTS SOUTHWARD.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
DENSE FOG ADVISORY UNTIL 8 AM EDT THIS MORNING FOR LMZ248-250.
&&
$$
SHORT TERM...ROLFSON
LONG TERM...TITUS
AVIATION...KC
MARINE...ROLFSON
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
139 AM EDT TUE MAY 27 2014
.SHORT TERM...(THIS EVENING THROUGH TUESDAY)
ISSUED AT 511 PM EDT MON MAY 26 2014
WATER VAPOR IMAGERY AND RUC ANALYSIS SHOW A BROAD RIDGE OVER CNTRL
NAMERICA. VIGOROUS LOOKING SHORTWAVE HAS ROUNDED THE RIDGE AND IS
MOVING ACROSS FAR NRN ONTARIO...TOO FAR N TO HAVE MUCH IF ANY IMPACT
FORCING-WISE ACROSS UPPER MI AS 500MB HEIGHTS ARE RISING SLIGHTLY
THIS AFTN. AT THE SFC...ASSOCIATED COLD FRONT APPEARS TO BE DRIFTING
ACROSS WRN LAKE SUPERIOR...BUT LAKE BREEZE DEVELOPMENT IS MAKING
IT DIFFICULT TO DETERMINE EXACT LOCATION OVER THE UPPER LAKES. AS
EXPECTED...CONSIDERABLE MOISTENING OF THE AIR MASS HAS OCCURRED OVER
THE LAST 12 TO 18HRS. 00Z KGRB SOUNDING SHOWED PRECIPITABLE WATER AT
0.5 INCHES/72PCT OF NORMAL WHILE 12Z SOUNDING SHOWED 1.45
INCHES/208PCT OF NORMAL. AS A RESULT...MORNING SUNSHINE LED TO QUICK
CU DEVELOPMENT THIS MORNING...AND NOW SCT SHRA AND ISOLD TSRA ARE
OCCURRING OVER MAINLY THE INTERIOR W 2/3RDS OF UPPER MI. LATEST SPC
MESOANALYIS SHOWS MLCAPES IN THE 500-1000J/KG RANGE. WEAK SHEAR
MOSTLY UNDER 20KT IS KEEPING STORMS IN CHECK. LOCALLY HIGHER DEEP
LAYER SHEAR CLOSER TO 30KT HAS LED TO A FEW STRONG STORMS IN NE WI
TO THE W AND NW OF KMNM. STORMS THERE HAVE BEEN SHOWING BRIEF
CIRCULATION AND HAIL SIGNATURES. UPSTREAM...BEHIND COLD FRONT...
CONSIDERABLE STRATUS AND FOG WAS OBSERVED EARLY THIS MORNING ACROSS
NW MN INTO NRN ONTARIO. WITH HIGH LATE MAY SUN ANGLE...THE
STRATUS/FOG HAS COMPLETELY MIXED OUT THIS AFTN. MEANWHILE...SHRA
THAT MOVED ACROSS LAKE MICHIGAN THIS MORNING HELPED GENERATE FOG
THAT HAS QUICKLY ADVECTED N TO THE UPPER MI SHORELINE. PER SATELLITE
IMAGERY AND WEBCAMS...FOG IS ALSO DEVELOPING OVER W AND CNTRL LAKE
SUPERIOR...APPARENTLY ALONG THE FRONTAL CONVERGENCE ZONE.
WITH ONGOING CONVECTION SOLELY EXISTING BECAUSE OF DAYTIME HEATING
AND RESULTING INSTABILITY...EXPECT SHRA/TSRA TO GRADUALLY END FROM N
TO S THIS EVENING. HOWEVER...THERE ARE INDICATIONS OF A WEAK
SHORTWAVE DRIFTING E FROM MN...AND MODELS INDICATE WEAK DEEP LAYER
QVECTOR CONVERGENCE SHIFTING ACROSS NRN WI/ADJACENT UPPER MI. IN
LIGHT OF THIS...WILL MAINTAIN SCHC POPS ACROSS THE WI/MI BORDER INTO
SCNTRL UPPER MI THRU THE NIGHT. OTHER ISSUE TONIGHT IS POTENTIAL OF
FOG/LOW CLOUDS AND PERHAPS SOME -DZ NEAR LAKE SUPERIOR. THE
DEVELOPMENT OF SOME FOG TODAY ON LAKE SUPERIOR GREATLY INCREASES THE
POTENTIAL FOR FOG/DZ NEAR THE LAKE WHERE WINDS SHIFT MORE DIRECTLY
ONSHORE WITH PASSAGE OF WEAK COLD FRONT DURING THE NIGHT. THUS...
FCST WILL REFLECT SOME FOG DEVELOPMENT NEAR LAKE SUPERIOR WITH BEST
CHC OF LOWER VIS AND -DZ OVER NCNTRL UPPER MI LATE TONIGHT INTO TUE
MORNING AS FLOW BECOME MORE SHARPLY UPSLOPE IN THAT AREA.
ANY MORNING FOG/LOW CLOUDS/-DZ NEAR LAKE SUPERIOR WILL GIVE WAY TO
SUNNY SKIES DURING THE AFTN AS DRIER AIR SPREADS S IN ASSOCIATION
WITH HUDSON BAY HIGH PRES RIDGE BUILDING SOUTHWARD INTO THE UPPER
LAKES. KEPT A SCHC MENTION OF -SHRA ALONG MI/WI BORDER INTO THE MID
AFTN HRS UNTIL DRIER AIR MAKES A STRONGER PRESENCE AS SFC BOUNDARY
CONTINUES TO DRIFT FARTHER S. IT WILL BE CONSIDERABLY COOLER NEAR
LAKE SUPERIOR ON TUE COMPARED TO TODAY UNDER NORTHERLY WIND ENHANCED
BY LAKE BREEZE COMPONENT. MANY LAKESIDE LOCATIONS WILL NOT GET OUT
OF THE 50S AND SOME MAY SPEND MUCH OF THE DAY IN THE 40S. ACROSS THE
S...MIXING TOWARD 800MB ON FCST SOUNDINGS SUGGESTS HIGHS WILL REACH
WELL INTO THE 70S.
.LONG TERM...(TUESDAY NIGHT THROUGH MONDAY)
ISSUED AT 456 PM EDT MON MAY 26 2014
TUE NIGHT INTO THU...AS THE MID LEVEL RIDGE BUILDS OVER THE
PLAINS...A SFC RIDGE WILL EXTEND FROM NRN ONTARIO INTO THE WRN GREAT
LAKES. AS A RESULT...DRY WEATHER WITH LIGHT WINDS WILL PREVAIL
ACROSS UPPER MICHIGAN. WHILE INLAND TEMPS WILL CLIMB INTO THE UPPER
70S INLAND WED AND THE LOWER 80S THU ...PROMINENT LAKE BREEZES WILL
KEEP READINGS IN THE UPPER 50S AND 60S ALONG THE GREAT LAKES.
THU NIGHT INTO FRI...THE GFS/GEM SUGGEST THAT THE RIDGE INTO THE
UPPER MS VALLEY WILL BE FAR ENOUGH TO THE WEST TO ALLOW A BACK DOOR
COLD FRONT TO SLIDE IN THE FROM NNE WHILE THE ECMWF WHICH PUSHES THE
RIDGE A BIT FARTHER TO THE EAST. EXPECT THERE MAY BE SOME
COOLING...ESPECIALLY OVER THE NORTH AS WINDS DEVELOP OFF OF LAKE
SUPERIOR. WITH A RELATIVELY DRY AIRMASS OVER THE AREA...ANY WEAK
SHRTWVS TOPPING THE RIDGE ARE NOT EXPECTED TO PRODUCE ANY PCPN.
SAT-MON...THE LAST SEVERAL RUNS OF THE ECMWF HAVE TRENDED SLOWER
WITH THE BREAKDOWN OF THE RIDGE RESULTING FROM A SHRTWV MOVING
TOWARD HUDSON BAY. THE GFS AND GEM HAVE RETAINED THERE SLOWER
SOLUTION AND HAVE ALSO TRENDED SLIGHTLY SLOWER. HOWEVER...TIMING
DIFFERENCES REMAIN AS THE FASTER ECMWF BRINGS THE FRONT AND
ASSOCIATED SHRA/TSRA CHANCES INTO UPPER MI SAT NIGHT INTO SUN WITH
DRY WEATHER BY SUN NIGHT AND MON WHILE THE GFS REMAINED SIGNFICANTLY
SLOWER. UNTIL THE DIFFERENCES ARE RESOLVED SHRA/TSRA CHANCES FROM SAT
NIGHT INTO MON...PER MDLS CONSENSUS AND ENSEMBLE MEANS...ARE
WARRANTED.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT)
ISSUED AT 137 AM EDT TUE MAY 27 2014
THE N WIND BEHIND A COLD FRONT PASSING THRU THE AREA EARLY THIS MRNG
WL BRING THE POTENTIAL FOR SOME LO CLDS/IFR CIGS AT MAINLY SAW...
WHERE THIS WIND PRESENTS A SHARPER UPSLOPE WIND COMPONENT. BUT THE
MAGNITUDE OF RECENT DRYING AT IWD AND ESPECIALLY CMX INDICATES
CONDITIONS LOWER THAN VFR ARE NOT LIKELY. IF THE MORE AGGRESSIVE
LLVL DRYING CONTINUES...THE LO CLDS FCST AT SAW MAY NOT MATERIALIZE.
ANY LO CLDS/FOG THAT FORM WL DSPT LATER THIS MORNING AS CONTINUED DRY
ADVECTION TO THE S OF BLDG HI PRES IN ONTARIO AND HIGH LATE MAY SUN
ANGLE DRY THE LLVLS.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 511 PM EDT MON MAY 26 2014
WITH RELATIVELY WEAK PRES GRADIENT TYPICAL OF THE WARM SEASON
DOMINATING THRU THIS FORECAST PERIOD...EXPECT WINDS MOSTLY UNDER
20KT TO PREVAIL. IN THE NEAR TERM...FOG THAT HAS DEVELOPED OVER
PORTIONS OF W AND CNTRL LAKE SUPERIOR WILL SPREAD S TO THE UPPER
MI SHORE TONIGHT AS COLD FRONT DRIFTS S INTO UPPER MI. THIS FOG
SHOULD DISSIPATE TUE MORNING AS WINDS BECOME MORE ANTICYCLONIC AND
DRIER AIR ADVECTS SOUTHWARD.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
DENSE FOG ADVISORY UNTIL 8 AM EDT THIS MORNING FOR LMZ248-250.
&&
$$
SHORT TERM...ROLFSON
LONG TERM...JLB
AVIATION...KC
MARINE...ROLFSON
AREA FORECAST DISCUSSION
NWS TWIN CITIES/CHANHASSEN MN
112 PM CDT TUE MAY 27 2014
.UPDATE...
ISSUED AT 100 PM CDT TUE MAY 27 2014
UPDATED TO INCLUDE 18Z AVIATION DISCUSSION BELOW.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 241 AM CDT TUE MAY 27 2014
LATEST RADAR IMAGERY SHOWS THE MAJORITY OF THE FORECAST AREA
PCPN-FREE... BUT THERE ARE AREAS OF SHOWERS WITH SOME OCCASIONAL
LIGHTNING. THE ACTIVITY IS FOCUSED ALONG THE NORTHERN PERIPHERY OF
A COMPACT MID-UPPER LEVEL SHORTWAVE FEATURE WHICH IS EVIDENT ON
WATER VAPOR IMAGERY AND BEST DEPICTED BY THE 400-300 MB PV FROM
THE RAP AND NAM. PCPN IS FOCUSED ALONG THE NORTHERN EDGE OF THE PV
ANOMALY... COINCIDENT WITH THE GRADIENT OF A COMPACT 300 MB JET IN
THE NEIGHBORHOOD OF 40 KT. THE FEATURE IS ALSO LENDING ITSELF TO
SOME MID-LEVEL DEFORMATION... WHICH IS HELPING THINGS OUT BY
PROVIDING A BIT OF MID-LEVEL FRONTOGENESIS. ALL OF THESE THINGS
ARE WORKING TOGETHER TO PRODUCE A SHIELD OF PATCHY PCPN WITH
EMBEDDED CONVECTION GIVEN THE LINGERING CONVECTIVE INSTABILITY
PRESENT OVER THE AREA... WITH MUCAPE VALUES FROM THE SPC SFCOA
RUNNING AROUND 250-500 J/KG. UNLIKE THE PAST FEW NIGHT... THE
THALER QG DIAGNOSTICS ARE EVEN SHOWING A HINT OF LARGE SCALE QG
FORCING WITH THIS FEATURE... AND MANAGE TO WRING OUT SOME QG-
FORCED PCPN THROUGH EARLY THIS MORNING. THE NAM AND RAP BOTH
SUGGEST THE MID-UPPER LEVEL FEATURE IS CURRENTLY NEARING ITS
NORTHERN MOST REACH... AND SHOULD BEGIN TO START SLOWLY SLIDING
SOUTHEAST AND WEAKEN AS IT SHEARS OUT A BIT DURING THE MORNING
HOURS. HOWEVER... AS WE PROGRESS THROUGH THE DAY WE SHOULD SEE
SOME FILTERED SUNSHINE AND WARMING ONCE AGAIN... WHICH WILL HELP
BUMP UP INSTABILITY... AND INCREASE THE CHANCES FOR ADDITIONAL
SHRA/TSRA WHEREVER WE HAVE LINGERING FORCING FROM THIS LARGER
SCALE FEATURE OR LOCALIZED WEAK LOW LEVEL FORCING FROM THE SURFACE
TROUGH WHICH REMAINS OVER THE AREA. OVERALL... THE IMPACT OF EACH
OF THOSE THINGS SHOULD BE SHIFTING SOUTHEAST THROUGH THE DAY... SO
WILL START TO SHIFT POPS SOUTHEAST LATE MORNING AND AFTERNOON
THROUGH THE EVENING... WHILE ALLOWING FOR A PERIOD OF SOMEWHAT
HIGHER POPS COINCIDENT WITH MAX HEATING.
HAVE SOME CONCERN WE COULD SEE SOME PCPN SNEAK IN FROM THE
NORTHWEST DURING THE EVENING HOURS DUE TO CONVECTION WHICH IS
EXPECTED UPSTREAM OVER THE DAKOTAS ONCE AGAIN... BUT WILL LEAVE
THAT OUT OF THE MIX FOR NOW WITH INDICATIONS FROM THE CAMS THAT IT
SHOULD REMAIN TO THE WEST/NORTHWEST. THE THALER QG DIAGNOSTICS
ALSO INDICATE INCREASED SUBSIDENCE FROM OUR NORTHWEST INTO CENTRAL
FORECAST AREA DURING THE EVENING... WHICH WOULD HELP MITIGATE THE
POTENTIAL OF ANYTHING UPSTREAM WORKING INTO THE AREA. ONCE
AGAIN... SEVERE WEATHER DOES NOT APPEAR TO BE A CONCERN IN OUR
AREA GIVEN A LACK OF DEEP LAYER AND LOW-LEVEL SHEAR. HOWEVER...
LOCALLY HEAVY RAIN COULD CERTAINLY BE AN ISSUE ONCE AGAIN WITH
SLOWLY MOVING STORMS AND REMAINING MOISTURE... PARTICULARLY OVER
THE SOUTHEAST HALF OF THE AREA THIS AFTERNOON. IN ADDITION...
COULD SEE SOME FUNNEL CLOUDS ONCE AGAIN THIS AFTERNOON SHOULD
UPDRAFTS COLLOCATE THEMSELVES WITH THE LINGERING SURFACE BOUNDARY
AS THEY DID YESTERDAY... AND MANAGE TO STRETCH THE BACKGROUND
SURFACE VERTICAL VORTICITY ALONG IT. THE BEST CHANCE OF THAT
OCCURRING WOULD APPEAR TO BE OVER THE SOUTH AND FAR SOUTHEAST
PORTION OF THE AREA... WHERE THE BOUNDARY IS EXPECTED TO BE
LOCATED LATER IN THE DAY WHEN THE MOST POTENT UPDRAFTS WOULD BE
EXPECTED.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 241 AM CDT TUE MAY 27 2014
LONGER TERM TRENDS CONTINUE TO SHOW A GENERAL DRYING TREND FOR THE
FIRST HALF OF THE PERIOD...ALONG WITH THE ABOVE NORMAL TEMPERATURE
TREND.
RIDGING ALOFT DEVELOPS OVER THE AREA WEDNESDAY. RESIDUAL
MOISTURE/HIGHER DEWPOINTS ARE DRIVEN WEST AS SURFACE HIGH DROPS
OVER THE GREAT LAKES. THIS WILL PROVIDE SOME MINOR COOLING...MAINLY
TO THE EAST INTO THURSDAY. AFTER THAT...TEMPERATURES SHOULD WARM
THROUGH 80S ACROSS THE AREA AS THE SURFACE FLOW BECOMES MORE
SOUTHEAST/SOUTH WITH TIME. THERE IS SOME THREAT OF ISOLATED
THUNDER INTO WEDNESDAY...MAINLY ACROSS SOUTH CENTRAL MN INTO THE
AFTERNOON...AS DRIER AIR WORKS TO THE EAST. SHOULD SEE SOME
TOWERING CUMULUS DEVELOP ALONG THE CONVERGENCE AREA TO THE
SOUTHWEST.
WITH ACTIVE NORTHERN STREAM THERE IS ALSO SOME THREAT OF REMNANTS
OF DAKOTAS CONVECTION MAKING IT INTO NORTHWEST MINNESOTA LATE
THURSDAY NIGHT...AND AGAIN LATE FRIDAY NIGHT. WILL CONTINUE TO
MENTION A SMALL POP IN THE NORTHWEST CWA THROUGH FRIDAY NIGHT. THE
REMAINDER OF THE CWA SHOULD REMAIN WARM AND DRY.
THE GFS AND ECMWF ARE IN FAIRLY GOOD AGREEMENT ON MOVING THE NEXT
COLD FRONT ACROSS THE AREA OVER THE WEEKEND. WE WILL HAVE DECENT
MOISTURE IN PLACE ONCE AGAIN WITH SOME ADDITIONAL TROPICAL PLUME
MOISTURE ADDED TO THE MIX AS THE FRONT MOVES THROUGH. HEAVY RAIN
WILL BE A THREAT ALONG WITH SOME SEVERE WEATHER POSSIBLE WITH THE
FRONTAL PASSAGE. THE GFS STALLS THE FRONT WELL INTO OUR CWA BY
MONDAY...WITH THE ECMWF DRIVING IT SOUTH TO AT LEAST THE MN/IA
BORDER BY THAT TIME. IN ANY CASE...WE SHOULD REMAIN IN AN ACTIVE
WEATHER PATTERN FOR THE WEEKEND AND INTO EARLY NEXT WEEK.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON)
ISSUED AT 103 PM CDT TUE MAY 27 2014
TRICKY FIRST FEW HOURS OF THE 27/18Z TAFS DUE TO SUCH VARIABILITY
IN LOW LEVEL MOISTURE AND SPOTTY SHOWERS...WHICH WILL ERODE THE
RE-FORM LOWER CEILINGS...ALL UNDERNEATH A DEPARTING ROTATING UPPER
LEVEL LOW. AS THE LOW EXITS FURTHER TO THE E...CEILINGS WILL
OVERALL IMPROVE TO VFR...MAINLY BY LATE THIS AFTN INTO THE EARLY
EVE HRS. CIGS WILL THEN WILL SCATTER OUT...LEAVING MAINLY HIGH
CLOUDS FOR TMRW AS HIGH PRES ARRIVES. WINDS MAINLY SE TO E WITH
SPEEDS 10 KT OR LESS.
KMSP...CEILINGS WILL LIKELY BOUNCE BETWEEN 2-4 KFT FOR THE FIRST
COUPLE HOURS OF THIS 18Z SET...THEN EVENTUALLY REMAIN ABOVE 4 KFT
FROM LATE THIS AFTN THRU THE DAY TMRW. OCNL SHWRS MAY STILL DRIFT
ACRS THE FIELD...BUT AM NOT XPCTG ANYTHING THAT WILL REDUCE VSBY
TO LESS THAN 6SM.
/OUTLOOK FOR KMSP/
WED NIGHT...VFR. SE WIND 5-10 KT.
THU...VFR. WIND SE 5-10 KT.
FRI...VFR. WIND SE 5-10 KT.
SAT...MAINLY VFR. POSSIBLE MVFR WITH CHC SHWRS/TSTMS. WIND S 10
KT.
&&
.MPX WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...NONE.
&&
$$
UPDATE...JPC
SHORT TERM...
LONG TERM...DWE
AVIATION...JPC
AREA FORECAST DISCUSSION
NWS TWIN CITIES/CHANHASSEN MN
614 AM CDT TUE MAY 27 2014
.UPDATE...
ISSUED AT 605 AM CDT TUE MAY 27 2014
UPDATED TO INCLUDE 12Z AVIATION DISCUSSION BELOW.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 241 AM CDT TUE MAY 27 2014
LATEST RADAR IMAGERY SHOWS THE MAJORITY OF THE FORECAST AREA
PCPN-FREE... BUT THERE ARE AREAS OF SHOWERS WITH SOME OCCASIONAL
LIGHTNING. THE ACTIVITY IS FOCUSED ALONG THE NORTHERN PERIPHERY OF A
COMPACT MID-UPPER LEVEL SHORTWAVE FEATURE WHICH IS EVIDENT ON WATER
VAPOR IMAGERY AND BEST DEPICTED BY THE 400-300 MB PV FROM THE RAP
AND NAM. PCPN IS FOCUSED ALONG THE NORTHERN EDGE OF THE PV
ANOMALY... COINCIDENT WITH THE GRADIENT OF A COMPACT 300 MB JET IN
THE NEIGHBORHOOD OF 40 KT. THE FEATURE IS ALSO LENDING ITSELF TO
SOME MID-LEVEL DEFORMATION... WHICH IS HELPING THINGS OUT BY
PROVIDING A BIT OF MID-LEVEL FRONTOGENESIS. ALL OF THESE THINGS ARE
WORKING TOGETHER TO PRODUCE A SHIELD OF PATCHY PCPN WITH EMBEDDED
CONVECTION GIVEN THE LINGERING CONVECTIVE INSTABILITY PRESENT OVER
THE AREA... WITH MUCAPE VALUES FROM THE SPC SFCOA RUNNING AROUND
250-500 J/KG. UNLIKE THE PAST FEW NIGHT... THE THALER QG DIAGNOSTICS
ARE EVEN SHOWING A HINT OF LARGE SCALE QG FORCING WITH THIS
FEATURE... AND MANAGE TO WRING OUT SOME QG-FORCED PCPN THROUGH EARLY
THIS MORNING. THE NAM AND RAP BOTH SUGGEST THE MID-UPPER LEVEL
FEATURE IS CURRENTLY NEARING ITS NORTHERN MOST REACH... AND SHOULD
BEGIN TO START SLOWLY SLIDING SOUTHEAST AND WEAKEN AS IT SHEARS OUT
A BIT DURING THE MORNING HOURS. HOWEVER... AS WE PROGRESS THROUGH
THE DAY WE SHOULD SEE SOME FILTERED SUNSHINE AND WARMING ONCE
AGAIN... WHICH WILL HELP BUMP UP INSTABILITY... AND INCREASE THE
CHANCES FOR ADDITIONAL SHRA/TSRA WHEREVER WE HAVE LINGERING FORCING
FROM THIS LARGER SCALE FEATURE OR LOCALIZED WEAK LOW LEVEL FORCING
FROM THE SURFACE TROUGH WHICH REMAINS OVER THE AREA. OVERALL... THE
IMPACT OF EACH OF THOSE THINGS SHOULD BE SHIFTING SOUTHEAST THROUGH
THE DAY... SO WILL START TO SHIFT POPS SOUTHEAST LATE MORNING AND
AFTERNOON THROUGH THE EVENING... WHILE ALLOWING FOR A PERIOD OF
SOMEWHAT HIGHER POPS COINCIDENT WITH MAX HEATING.
HAVE SOME CONCERN WE COULD SEE SOME PCPN SNEAK IN FROM THE NORTHWEST
DURING THE EVENING HOURS DUE TO CONVECTION WHICH IS EXPECTED
UPSTREAM OVER THE DAKOTAS ONCE AGAIN... BUT WILL LEAVE THAT OUT OF
THE MIX FOR NOW WITH INDICATIONS FROM THE CAMS THAT IT SHOULD REMAIN
TO THE WEST/NORTHWEST. THE THALER QG DIAGNOSTICS ALSO INDICATE
INCREASED SUBSIDENCE FROM OUR NORTHWEST INTO CENTRAL FORECAST AREA
DURING THE EVENING... WHICH WOULD HELP MITIGATE THE POTENTIAL OF
ANYTHING UPSTREAM WORKING INTO THE AREA. ONCE AGAIN... SEVERE
WEATHER DOES NOT APPEAR TO BE A CONCERN IN OUR AREA GIVEN A LACK OF
DEEP LAYER AND LOW-LEVEL SHEAR. HOWEVER... LOCALLY HEAVY RAIN COULD
CERTAINLY BE AN ISSUE ONCE AGAIN WITH SLOWLY MOVING STORMS AND
REMAINING MOISTURE... PARTICULARLY OVER THE SOUTHEAST HALF OF THE
AREA THIS AFTERNOON. IN ADDITION... COULD SEE SOME FUNNEL CLOUDS
ONCE AGAIN THIS AFTERNOON SHOULD UPDRAFTS COLLOCATE THEMSELVES WITH
THE LINGERING SURFACE BOUNDARY AS THEY DID YESTERDAY... AND MANAGE
TO STRETCH THE BACKGROUND SURFACE VERTICAL VORTICITY ALONG IT. THE
BEST CHANCE OF THAT OCCURRING WOULD APPEAR TO BE OVER THE SOUTH AND
FAR SOUTHEAST PORTION OF THE AREA... WHERE THE BOUNDARY IS EXPECTED
TO BE LOCATED LATER IN THE DAY WHEN THE MOST POTENT UPDRAFTS WOULD
BE EXPECTED.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 241 AM CDT TUE MAY 27 2014
LONGER TERM TRENDS CONTINUE TO SHOW A GENERAL DRYING TREND FOR THE
FIRST HALF OF THE PERIOD...ALONG WITH THE ABOVE NORMAL TEMPERATURE TREND.
RIDGING ALOFT DEVELOPS OVER THE AREA WEDNESDAY. RESIDUAL
MOISTURE/HIGHER DEWPOINTS ARE DRIVEN WEST AS SURFACE HIGH DROPS
OVER THE GREAT LAKES. THIS WILL PROVIDE SOME MINOR COOLING...MAINLY
TO THE EAST INTO THURSDAY. AFTER THAT...TEMPERATURES SHOULD WARM
THROUGH 80S ACROSS THE AREA AS THE SURFACE FLOW BECOMES MORE
SOUTHEAST/SOUTH WITH TIME. THERE IS SOME THREAT OF ISOLATED
THUNDER INTO WEDNESDAY...MAINLY ACROSS SOUTH CENTRAL MN INTO THE
AFTERNOON...AS DRIER AIR WORKS TO THE EAST. SHOULD SEE SOME
TOWERING CUMULUS DEVELOP ALONG THE CONVERGENCE AREA TO THE
SOUTHWEST.
WITH ACTIVE NORTHERN STREAM THERE IS ALSO SOME THREAT OF REMNANTS
OF DAKOTAS CONVECTION MAKING IT INTO NORTHWEST MINNESOTA LATE
THURSDAY NIGHT...AND AGAIN LATE FRIDAY NIGHT. WILL CONTINUE TO
MENTION A SMALL POP IN THE NORTHWEST CWA THROUGH FRIDAY NIGHT. THE
REMAINDER OF THE CWA SHOULD REMAIN WARM AND DRY.
THE GFS AND ECMWF ARE IN FAIRLY GOOD AGREEMENT ON MOVING THE NEXT
COLD FRONT ACROSS THE AREA OVER THE WEEKEND. WE WILL HAVE DECENT
MOISTURE IN PLACE ONCE AGAIN WITH SOME ADDITIONAL TROPICAL PLUME
MOISTURE ADDED TO THE MIX AS THE FRONT MOVES THROUGH. HEAVY RAIN
WILL BE A THREAT ALONG WITH SOME SEVERE WEATHER POSSIBLE WITH THE
FRONTAL PASSAGE. THE GFS STALLS THE FRONT WELL INTO OUR CWA BY
MONDAY...WITH THE ECMWF DRIVING IT SOUTH TO AT LEAST THE MN/IA
BORDER BY THAT TIME. IN ANY CASE...WE SHOULD REMAIN IN AN ACTIVE
WEATHER PATTERN FOR THE WEEKEND AND INTO EARLY NEXT WEEK.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z WEDNESDAY MORNING)
ISSUED AT 605 AM CDT TUE MAY 27 2014
A DIFFICULT FORECAST PERIOD LOOKS TO BE IN STORE... PARTICULARLY
FOR THE FIRST 6-12 HOURS. THE SURFACE TROUGH REMAINS IN THE
VICINITY... AND WILL BE THE FOCUS FOR CONVECTION LATER THIS
AFTERNOON ONCE THE INSTABILITY INCREASES. HOWEVER... BEST
INDICATIONS FROM THE HIGH RESOLUTION GUIDANCE AND EXTRAPOLATION OF
TRENDS WOULD SUGGEST THE MAIN ACTION WITH THAT REJUVENATION WILL
BE SOUTHEAST OF THE TAF SITES. HOWEVER... EVEN IF THE FORECAST
SITES MISS OUT ON LATER CONVECTION... THEY FIRST NEED TO DEAL WITH
THE AREA OF PCPN CURRENTLY ROTATING IN PLACE OVER THE AREA. THIS
PCPN IS BEING FORCED BY A MID-UPPER LEVEL DISTURBANCE WHICH MOVED
NORTHEAST INTO SOUTHERN MINNESOTA OVERNIGHT. IT IS EXPECTED TO
WEAKEN SOME AND DRIFT SOUTHEAST AS THE DAY PROGRESSES... WHICH
SHOULD EVENTUALLY DRAG ITS MORE WIDESPREAD PCPN AWAY FROM THE TAF
SITES. BUT IN THE MEANTIME WE/LL NEED TO DEAL WITH ITS PCPN AND
ASSOCIATED REDUCED VISIBILITIES AND CEILINGS. THERE IS CURRENTLY A
HUGE RANGE IN FLIGHT CONDITIONS ACROSS THE AREA... WITH
IMPROVEMENT TO THE NORTHWEST... WHICH WILL EVENTUALLY OVERSPREAD
THE AREA TONIGHT. FORECASTS ARE BASED TO A LARGE DEGREE ON CURRENT
OBSERVATIONS THEN TRENDING TOWARD THE RAP AND NAM SOLUTIONS. DON/T
HAVE A TON OF CONFIDENCE BEYOND THE SHORT TERM IN EXPLICITLY
INCLUDING PCPN OR OVERLY POOR FLIGHT CONDITIONS. HOWEVER... THINGS
WILL LIKELY NEED TO BE WATCHED CLOSELY AND AMENDMENTS ARE LIKELY
FOR A TIME TODAY.
KMSP...FORECAST CONFIDENCE IS LOW OVERALL... WITH RESPECT TO
CEILINGS AND VISIBILITIES THIS MORNING. ONCE THE CURRENT BATCH OF
PCPN WORKS OUT THEN WE SHOULD SEE IMPROVEMENT TO VFR... BUT IT/S
POSSIBLE WE COULD STILL BE CLOSE ENOUGH TO THE SURFACE BOUNDARY
AND WEAKENING UPPER LEVEL DISTURBANCE TO SEE SOME CONVECTION
DEVELOP THIS AFTERNOON... WHICH WOULD RESULT IN CONDITIONS WORSE
THAN CURRENTLY FORECAST. OVERALL... THINGS WILL NEED TO BE WATCHED
AND ADJUSTED THROUGH MUCH OF THE DAY BASED ON TRENDS.
/OUTLOOK FOR KMSP/
WEDNESDAY AFTERNOON...BRIEF MVFR CONDITIONS POSSIBLE WITH A CHANCE
OF PCPN... OTHERWISE VFR. EAST WIND LESS THAN 5 KT BECOMING SOUTHEAST.
WEDNESDAY NIGHT THROUGH FRIDAY...VFR. SOUTHEAST WIND LESS THAN 10
KT INCREASING TO 5 TO 15 KT THURSDAY AFTERNOON THEN 10 TO 20 KT FRIDAY.
&&
.MPX WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...NONE.
&&
$$
UPDATE...
SHORT TERM...
LONG TERM...DWE
AVIATION...
AREA FORECAST DISCUSSION
NWS TWIN CITIES/CHANHASSEN MN
312 AM CDT TUE MAY 27 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 241 AM CDT TUE MAY 27 2014
LATEST RADAR IMAGERY SHOWS THE MAJORITY OF THE FORECAST AREA
PCPN-FREE... BUT THERE ARE AREAS OF SHOWERS WITH SOME OCCASIONAL
LIGHTNING. THE ACTIVITY IS FOCUSED ALONG THE NORTHERN PERIPHERY OF A
COMPACT MID-UPPER LEVEL SHORTWAVE FEATURE WHICH IS EVIDENT ON WATER
VAPOR IMAGERY AND BEST DEPICTED BY THE 400-300 MB PV FROM THE RAP
AND NAM. PCPN IS FOCUSED ALONG THE NORTHERN EDGE OF THE PV
ANOMALY... COINCIDENT WITH THE GRADIENT OF A COMPACT 300 MB JET IN
THE NEIGHBORHOOD OF 40 KT. THE FEATURE IS ALSO LENDING ITSELF TO
SOME MID-LEVEL DEFORMATION... WHICH IS HELPING THINGS OUT BY
PROVIDING A BIT OF MID-LEVEL FRONTOGENESIS. ALL OF THESE THINGS ARE
WORKING TOGETHER TO PRODUCE A SHIELD OF PATCHY PCPN WITH EMBEDDED
CONVECTION GIVEN THE LINGERING CONVECTIVE INSTABILITY PRESENT OVER
THE AREA... WITH MUCAPE VALUES FROM THE SPC SFCOA RUNNING AROUND
250-500 J/KG. UNLIKE THE PAST FEW NIGHT... THE THALER QG DIAGNOSTICS
ARE EVEN SHOWING A HINT OF LARGE SCALE QG FORCING WITH THIS
FEATURE... AND MANAGE TO WRING OUT SOME QG-FORCED PCPN THROUGH EARLY
THIS MORNING. THE NAM AND RAP BOTH SUGGEST THE MID-UPPER LEVEL
FEATURE IS CURRENTLY NEARING ITS NORTHERN MOST REACH... AND SHOULD
BEGIN TO START SLOWLY SLIDING SOUTHEAST AND WEAKEN AS IT SHEARS OUT
A BIT DURING THE MORNING HOURS. HOWEVER... AS WE PROGRESS THROUGH
THE DAY WE SHOULD SEE SOME FILTERED SUNSHINE AND WARMING ONCE
AGAIN... WHICH WILL HELP BUMP UP INSTABILITY... AND INCREASE THE
CHANCES FOR ADDITIONAL SHRA/TSRA WHEREVER WE HAVE LINGERING FORCING
FROM THIS LARGER SCALE FEATURE OR LOCALIZED WEAK LOW LEVEL FORCING
FROM THE SURFACE TROUGH WHICH REMAINS OVER THE AREA. OVERALL... THE
IMPACT OF EACH OF THOSE THINGS SHOULD BE SHIFTING SOUTHEAST THROUGH
THE DAY... SO WILL START TO SHIFT POPS SOUTHEAST LATE MORNING AND
AFTERNOON THROUGH THE EVENING... WHILE ALLOWING FOR A PERIOD OF
SOMEWHAT HIGHER POPS COINCIDENT WITH MAX HEATING.
HAVE SOME CONCERN WE COULD SEE SOME PCPN SNEAK IN FROM THE NORTHWEST
DURING THE EVENING HOURS DUE TO CONVECTION WHICH IS EXPECTED
UPSTREAM OVER THE DAKOTAS ONCE AGAIN... BUT WILL LEAVE THAT OUT OF
THE MIX FOR NOW WITH INDICATIONS FROM THE CAMS THAT IT SHOULD REMAIN
TO THE WEST/NORTHWEST. THE THALER QG DIAGNOSTICS ALSO INDICATE
INCREASED SUBSIDENCE FROM OUR NORTHWEST INTO CENTRAL FORECAST AREA
DURING THE EVENING... WHICH WOULD HELP MITIGATE THE POTENTIAL OF
ANYTHING UPSTREAM WORKING INTO THE AREA. ONCE AGAIN... SEVERE
WEATHER DOES NOT APPEAR TO BE A CONCERN IN OUR AREA GIVEN A LACK OF
DEEP LAYER AND LOW-LEVEL SHEAR. HOWEVER... LOCALLY HEAVY RAIN COULD
CERTAINLY BE AN ISSUE ONCE AGAIN WITH SLOWLY MOVING STORMS AND
REMAINING MOISTURE... PARTICULARLY OVER THE SOUTHEAST HALF OF THE
AREA THIS AFTERNOON. IN ADDITION... COULD SEE SOME FUNNEL CLOUDS
ONCE AGAIN THIS AFTERNOON SHOULD UPDRAFTS COLLOCATE THEMSELVES WITH
THE LINGERING SURFACE BOUNDARY AS THEY DID YESTERDAY... AND MANAGE
TO STRETCH THE BACKGROUND SURFACE VERTICAL VORTICITY ALONG IT. THE
BEST CHANCE OF THAT OCCURRING WOULD APPEAR TO BE OVER THE SOUTH AND
FAR SOUTHEAST PORTION OF THE AREA... WHERE THE BOUNDARY IS EXPECTED
TO BE LOCATED LATER IN THE DAY WHEN THE MOST POTENT UPDRAFTS WOULD
BE EXPECTED.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 241 AM CDT TUE MAY 27 2014
LONGER TERM TRENDS CONTINUE TO SHOW A GENERAL DRYING TREND FOR THE
FIRST HALF OF THE PERIOD...ALONG WITH THE ABOVE NORMAL TEMPERATURE TREND.
RIDGING ALOFT DEVELOPS OVER THE AREA WEDNESDAY. RESIDUAL
MOISTURE/HIGHER DEWPOINTS ARE DRIVEN WEST AS SURFACE HIGH DROPS
OVER THE GREAT LAKES. THIS WILL PROVIDE SOME MINOR COOLING...MAINLY
TO THE EAST INTO THURSDAY. AFTER THAT...TEMPERATURES SHOULD WARM
THROUGH 80S ACROSS THE AREA AS THE SURFACE FLOW BECOMES MORE
SOUTHEAST/SOUTH WITH TIME. THERE IS SOME THREAT OF ISOLATED
THUNDER INTO WEDNESDAY...MAINLY ACROSS SOUTH CENTRAL MN INTO THE
AFTERNOON...AS DRIER AIR WORKS TO THE EAST. SHOULD SEE SOME
TOWERING CUMULUS DEVELOP ALONG THE CONVERGENCE AREA TO THE
SOUTHWEST.
WITH ACTIVE NORTHERN STREAM THERE IS ALSO SOME THREAT OF REMNANTS
OF DAKOTAS CONVECTION MAKING IT INTO NORTHWEST MINNESOTA LATE
THURSDAY NIGHT...AND AGAIN LATE FRIDAY NIGHT. WILL CONTINUE TO
MENTION A SMALL POP IN THE NORTHWEST CWA THROUGH FRIDAY NIGHT. THE
REMAINDER OF THE CWA SHOULD REMAIN WARM AND DRY.
THE GFS AND ECMWF ARE IN FAIRLY GOOD AGREEMENT ON MOVING THE NEXT
COLD FRONT ACROSS THE AREA OVER THE WEEKEND. WE WILL HAVE DECENT
MOISTURE IN PLACE ONCE AGAIN WITH SOME ADDITIONAL TROPICAL PLUME
MOISTURE ADDED TO THE MIX AS THE FRONT MOVES THROUGH. HEAVY RAIN
WILL BE A THREAT ALONG WITH SOME SEVERE WEATHER POSSIBLE WITH THE
FRONTAL PASSAGE. THE GFS STALLS THE FRONT WELL INTO OUR CWA BY
MONDAY...WITH THE ECMWF DRIVING IT SOUTH TO AT LEAST THE MN/IA
BORDER BY THAT TIME. IN ANY CASE...WE SHOULD REMAIN IN AN ACTIVE
WEATHER PATTERN FOR THE WEEKEND AND INTO EARLY NEXT WEEK.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT)
ISSUED AT 1107 PM CDT MON MAY 26 2014
THERE IS A SLOW MOVING SYSTEM PASSING THROUGH MN/WI...WHICH MEANS
SCATTERED SHOWERS WITH ISOLATED THUNDERSTORMS WILL CONTINUE
THROUGH MOST OF THE NIGHT. THERE WILL AGAIN BE A BETTER CHANCE FOR
THUNDER TOMORROW AFTERNOON. THE RAIN...LOOK FOR WINDS TO BECOME
NEAR CALM AND THE POTENTIAL FOR FOG OR MIST EARLY IN THE MORNING.
KMSP...
NO MAJOR AVIATION WEATHER CONCERNS ARE EXPECTED TONIGHT OR
TOMORROW MORNING. LIGHT SHOWERS ARE POSSIBLE BUT THE THREAT FOR
THUNDER IS VERY MINIMAL.
/OUTLOOK FOR KMSP/
WED...VFR. SE WND LESS THAN 5 KT.
WED NGT THRU FRI. VFR. S-SE WND 5 KT OR LESS BCMG SE 10-15 KT FRI.
&&
.MPX WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...NONE.
&&
$$
SHORT TERM...TRH
LONG TERM...DWE
AVIATION...CLF
AREA FORECAST DISCUSSION...UPDATED AVIATION
NWS ST LOUIS MO
1147 PM CDT Mon May 26 2014
.UPDATE:
Issued at 949 PM CDT Mon May 26 2014
Quick update to bring likely PoPs late this evening into the metro
area before tapering them off as the forcing weakens overnight.
Showers and thunderstorms have progressed steadily eastward the
past two hours eastward into east central Missouri and will likely
continue to move east and northeast through 05Z per the RAP.
Britt
Issued at 758 PM CDT Mon May 26 2014
Updated forecast to increase PoPs over central and northeast
Missouri. This is where showers and thunderstorms are being
generated by a pocket of low level moisture convergence ahead of
weak mid level vort max. Latest RAP shows this convergence
weakening over next few hours, though the HRRR reflectivity does
hold on to some scattered thunderstorms through the mid evening
hours across eastern Missouri. Will go will a slow decrease in
areal coverage of showers and thunderstorms the next few hours
based on this guidance. Only minor tweaks needed to going
temperature and wind forecast.
Britt
&&
.SHORT TERM: (Through Late Tonight)
Issued at 355 PM CDT Mon May 26 2014
Decent amount of convection developed across most of the FA this
afternoon. Since daytime heating appeared to be the primary
driving force, loss of heating as we head into the evening hours
should lead to a decrease in coverage and intensity. There does
appear to be a bit of shortwave energy brushing northwest areas of
the CWA early tonight, so have held onto the precip the longest in that
area.
Not sure how much activity there will be heading into the predawn
hours, but there does seem to be some consensus that shortwave
sweeping through east side of upper low may approach s MO during
by daybreak. So have reintroduced some low PoPs over southern
sections of the FA for late tonight.
Truett
.LONG TERM: (Tuesday through Next Monday)
Issued at 355 PM CDT Mon May 26 2014
Precip chances will continue to be the primary concern throughout
much of this week due to a combination of features propagating
through the unseasonably strong upper ridge that remains anchored
over the central CONUS. Of course, the main feature is the cutoff
low which is still progged to continue to toss pieces of energy our
way as it gradually heads to the LA coast by Thursday. Meanwhile,
12z model runs are also continuing the idea of weak shortwave
overtopping the ridge at midweek, with this feature trickling down
the east side of the ridge and into the Mississippi Valley on
Thursday.
These features, combined with the weakly unstable and uncapped AMS
that will remain locked over the area, should mean a persistent
threat of showers and thunderstorms. It still appears that PoPs
will continue to exhibit a fairly strong diurnal swing, and have
attempted to place highest PoPs where the combination of instability
and weak dynamics will co-exist during the afternoon hours.
Unfortunately, this pattern does not lend itself to a high level
of precision regarding timing and location, so additional
refinement will be limited to first period/nowcast part of
forecast.
For Friday and Saturday, the latest raw model data and associated
MOS continue to suggest low PoPs across the FA, despite the fact
that by this time the upper low will be over the Gulf and
500mb heights over the mid-Mississippi Valley will be aoa
586dm. There does seem to be some feeble weakness in the UA field
that gets locked beneath the ridge (perhaps a remnant of Thursday
shortwave), and this combined with the fact that this threat has
been a consistent message for several days have continued low
chance PoPs during this time, with Saturday`s PoPs confined to
areas along and west of Mississippi River in most unstable AMS.
Precip chances should increase a bit more heading into next week
as a series of shortwaves begin to flatten the ridge.
With no real change in AMS over the next 7 days temperatures
should follow persistence in most areas, with highs in the 80s and
lows in the 60s.
Truett
&&
.AVIATION: (For the 06z TAFs through 06z Tuesday Night)
Issued at 1135 PM CDT Mon May 26 2014
Specifics for KCOU, KUIN: Some light fog is possible overnight if
winds become calm and skies clear out. Scattered thunderstorms are
expected to develop after 18z and dissipate with the loss of
daytime heating. The prevailing wind direction remains south or
southwest, but outflow boundaries from earlier convection may
temporarily alter the flow.
Specifics for KSTL, KSUS, KCPS: Areas of precipitation have moved
away from the St. Louis metro area terminals, but the additional
low-level moisture may contribute to overnight fog formation at
KSUS/KCPS, especially if any clearing occurs. T/Td spreads at KSTL
at TAF issuance were large enough to limit the expected fog
threat, but this will need to be monitored through the night.
Scattered thunderstorms are expected to develop after 18z and
dissipate with the loss of daytime heating. The prevailing wind
direction remains south or southwest, but outflow boundaries from
earlier convection may temporarily alter the flow.
Kanofsky
&&
.LSX WATCHES/WARNINGS/ADVISORIES:
MO...NONE.
IL...NONE.
&&
$$
WFO LSX
AREA FORECAST DISCUSSION
NWS NORTH PLATTE NE
602 PM CDT WED MAY 28 2014
.SYNOPSIS...
ISSUED AT 356 PM CDT WED MAY 28 2014
THE CENTRAL PLAINS ARE UNDERNEATH A LARGE 500HPA RIDGE AHEAD OF AN
INCOMING TROUGH AFFECTING THE PACIFIC NORTHWEST. THE AREA OF LOW
PRESSURE ALOFT HAS MOVED INTO THE MISSISSIPPI DELTA REGION. AT THE
SURFACE...ONE LOW PRESSURE SYSTEM EXISTS ACROSS THE FAR NORTHERN
PLAINS AND ONE OVER THE LOWER GREAT LAKES. HIGH PRESSURE SITUATED IN
SOUTHERN COLORADO COMBINED WITH THE UPPER LEVEL RIDGE ARE PROVIDING
HOT AND MAINLY DRY CONDITIONS TO NEBRASKA.
&&
.SHORT TERM...(THIS EVENING THROUGH THURSDAY)
ISSUED AT 356 PM CDT WED MAY 28 2014
ISOLATED THUNDERSTORMS ARE POSSIBLE THIS AFTERNOON ACROSS PORTIONS
OF THE WESTERN SANDHILLS AND SOUTHWEST NEBRASKA. THE HRRR MODEL HAS
BEEN HINTING AT DEVELOPMENT FOR SEVERAL RUNS AND A CUMULUS FIELD
SHOWED UP ON VISIBLE SATELLITE EARLY AFTERNOON. IN ADDITION...MANY
LOCATIONS HAVE REACHED THE CONVECTIVE TEMPERATURE BASED ON THE
28/12Z KLBF RAOB. ANY THUNDERSTORM SHOULD DISSIPATE SHORTLY AFTER
SUNSET AS THE CAP STRENGTHENS. TEMPERATURE TRENDS FOR OVERNIGHT LOWS
AND THURSDAY HIGHS LOOKED GOOD FROM PREVIOUS FORECAST. ONLY CHANGES
WERE DROPPED A DEGREE OR SO TONIGHT BASED ON GUIDANCE AND THE DEW
POINT FORECAST...AND RAISED A DEGREE THURSDAY FOR CONTINUED SUNSHINE
AND SOUTH WINDS. MOISTURE ADVECTS INTO THE AREA THURSDAY AHEAD OF
THE NEXT WEATHER SYSTEM...AS SURFACE DEW POINTS REACH THE LOWER 60S
ACROSS NORTH CENTRAL NEBRASKA. ANY PRECIPITATION WILL HOLD OFF UNTIL
THE LONG TERM FORECAST PERIOD.
.LONG TERM...(THURSDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 356 PM CDT WED MAY 28 2014
AN ACTIVE WEATHER PATTERN WILL BE ONGOING ACROSS THE CENTRAL
PLAINS LATER THIS WEEK INTO NEXT WEEK.
THE UPPER LEVEL LOW CURRENTLY OVER ARKANSAS/LOUISIANA AND EASTERN
TEXAS WILL SEE LITTLE MOVEMENT OVER THE NEXT SEVERAL DAYS AS IT
BECOMES CUTOFF FROM THE GENERAL FLOW AND REMAINS NEARLY STATIONARY
UNDER THE RIDGE WHICH WILL BE CENTERED OVER THE NORTHERN PLAINS
AND UPPER MISSISSIPPI RIVER VALLEY AT 00Z FRIDAY. OVER THE NEXT
SEVERAL DAYS THE RIDGE AXIS WILL MOVE EASTWARD AS A STRONG TROUGH
MOVES ONSHORE OVER THE WEST COAST ON SATURDAY. THIS PATTERN SHIFT
WILL BRING STRONGER UPPER LEVEL FLOW TO THE REGION...ALONG WITH A
MULTITUDE OF WEAK BOUTS OF SHORTWAVE ENERGY FROM THE SOUTHWEST
FLOW INTO THE CENTRAL PLAINS.
ALTHOUGH THE MODELS ARE IN GOOD CONSENSUS WITH THE GENERAL
PATTERN...THERE IS SOME DISCONTINUITY ON THE TRACK OF THE
SHORTWAVES AS WELL AS THE MOVEMENT OF THE LONGWAVE TROUGH OUT WEST
INTO NEXT WEEK. THEREFORE...USED A MODEL CONSENSUS FOR MUCH OF THE
LONG TERM PORTION OF THE FORECAST AS CONFIDENCE ISN/T REAL HIGH ON
TIMING OF PRECIPITATION CHANCES.
STARTING THURSDAY EVENING...RIDGING IS STILL WELL IN PLACE ACROSS
THE CENTRAL PLAINS AND WITH THE MID-LEVEL FLOW NORTH-NORTHWEST
CONVECTION DEVELOPING ACROSS NORTHERN COLORADO AND THE WESTERN
PANHANDLE MAY JUST SKIRT THE NORTHWEST PART OF THE FORECAST AREA.
SO LIMITED THE CHANCES FOR SHOWERS AND STORMS TO PORTIONS OF
SHERIDAN COUNTY.
DURING THE DAY ON FRIDAY...SHOWER AND STORM CHANCES WILL AGAIN BE
CONFINED TO AREAS OVER THE WESTERN PART OF THE FORECAST
AREA...MAINLY THE PANHANDLE AND THE WESTERN SANDHILLS AS
CONVECTION SHOULD DEVELOP OVER THE HIGHER ELEVATIONS ACROSS
COLORADO AND THE WESTERN PANHANDLE WHERE THERE WILL BE BETTER
SHORTWAVE ENERGY...ALONG WITH SOME UPSLOPE FLOW AND A FOCUS OF
MOISTURE TRANSPORT. THE LOW LEVEL JET WILL VEER INTO THE EVENING
WHICH WILL THEN SUPPORT STORMS TRANSITIONING EAST ACROSS NORTHERN
NEBRASKA AND INTO SOUTH DAKOTA. PRECIPITATION CHANCES HAVE BEEN
TRENDED IN THIS DIRECTION.
ON SATURDAY A FAIRLY STRONG SHORTWAVE TROUGH IS EXPECTED TO MOVE
ACROSS THE NORTHERN PLAINS AND INTO NORTHERN NEBRASKA. THIS WILL
PUSH A COLD FRONT INTO THE FORECAST AREA THROUGH THE DAY HOWEVER
IT DOESN/T LOOK TO PROGRESS VERY FAR EAST. EXPECTING TO GET
DEVELOPMENT ALONG THE FRONT SATURDAY AFTERNOON. ANY STORMS
DEVELOPING ON SATURDAY COULD GET STRONG TO SEVERE AS THE INCREASE
IN THE UPPER LEVEL FLOW WILL HELP TO STRENGTHEN THE DEEP LAYER
SHEAR TO GET STORMS HAVE THE POTENTIAL TO BECOME MORE ORGANIZED.
BEYOND SATURDAY IS WHEN THE DIFFERENCES IN TIMING OF ANY SHORTWAVE
ENERGY MOVING THROUGH THE AREA BECOME MORE APPARENT. SO THE
CHANCES FOR SHOWERS AND THUNDERSTORMS FOR MUCH OF THE AREA
CONTINUE DAILY THROUGH THE EARLY PORTIONS OF NEXT WEEK. ALTHOUGH
SEVERE STORMS ARE NOT OUT OF THE QUESTION ANY DAY AS THERE SHOULD
BE DECENT INSTABILITY AND WIND SHEER EACH DAY...THERE ISN/T A PERIOD
THAT LOOKS BETTER THAN OTHERS TO HIGHLIGHT THE CHANCES FOR SEVERE
STORMS.
AS FOR TEMPERATURES...FRIDAY WILL BE ANOTHER WARM DAY WITH HIGHS
IN THE MID TO UPPER 80S. ON SATURDAY...THE NORTHWEST MAY BE A BIT
COOLER IN THE 70S AS THE COLD FRONT MOVES THROUGH THAT
AREA...WITH THE REMAINDER OF THE FORECAST AREA IN THE 80S. THEN
THE REST OF THE FORECAST PERIOD HAS HIGHS IN THE 70S AND 80S AS
SHOWERS/STORMS/CLOUDS WILL PLAGUE MUCH OF THE AREA KEEPING
TEMPERATURES IN CHECK. AS FOR LOWS...DEWPOINTS IN THE UPPER 40S TO
LOW 60S THROUGHOUT THE PERIOD WILL KEEP TEMPERATURES FROM FALLING
TOO FAR AND WILL STAY SLIGHTLY ABOVE NORMAL.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z THURSDAY EVENING)
ISSUED AT 601 PM CDT WED MAY 28 2014
OVER THE NEXT 24 HOURS...EXPECT MAINLY CLEAR SKIES AT THE KLBF AND
KVTN TERMINALS. SOME SCATTERED MID LEVEL CLOUDINESS AON 8000 FT
AGL IS POSSIBLE ON THURSDAY AFTER 19Z. WINDS WILL BE FROM THE
SOUTHEAST TONIGHT AT UNDER 10 KTS. LOOK FOR WINDS TO INCREASE FROM
THE SOUTHEAST AND SOUTH SOUTHEAST AT 10 TO 20 KTS THURSDAY
AFTERNOON. SOME GUSTS MAY APPROACH 25 KTS AT THE KVTN TERMINAL
THURSDAY AFTERNOON.
&&
.LBF WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...DS
SHORT TERM...DS
LONG TERM...BROOKS
AVIATION...CLB
AREA FORECAST DISCUSSION
NWS NORTH PLATTE NE
1239 PM CDT TUE MAY 27 2014
.UPDATE...
ISSUED AT 1033 AM CDT TUE MAY 27 2014
THE FORECAST WAS UPDATED FOR AREAL COVERAGE OF SHOWER AND
THUNDERSTORM CHANCES THIS AFTERNOON. 27.12Z KLBF SOUNDING SHOWED
STEEP LAPSE RATES IN THE MID LEVELS WITH A GOOD AMOUNT OF
INSTABILITY. FORECAST MODELS INDICATE THIS WILL CHANGE LITTLE
THROUGH THE DAY. SO EXPECTING TO GET CUMULUS TO DEVELOP ALONG WITH
SOME SHOWERS AND THUNDERSTORMS THIS AFTERNOON UPON REACHING
SURFACE CONVECTIVE TEMPERATURE. MOISTURE WON/T BE GREAT THOUGH SO
THINKING COVERAGE SHOULD BE LIMITED TO ISOLATED...AND HAVE THE
CHANCES MAINLY OVER THE EASTERN PARTS OF THE FORECAST AREA AND THE
NORTHWEST WHERE THERE WILL BE SLIGHTLY MORE MOISTURE. STEERING
FLOW IS LIGHT...AND DEEP LAYER SHEAR IS MINIMAL SO EXPECTING
GENERALLY SLOW MOVING GARDEN VARIETY TYPE SHOWERS AND STORMS.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 316 AM CDT TUE MAY 27 2014
TODAY AND TONIGHT...THE MODEL CONSENSUS INDICATES GOOD MOISTURE WILL
REMAIN IN PLACE TODAY FOR ADDITIONAL DIURNAL TSTM DEVELOPMENT. WINDS
ALOFT WILL REMAIN WEAK AND CAPE MODEST. K INDICES SHOULD RISE TO
AROUND 35C AND PRECIPITABLE WATER TO 1 TO 1.25 INCHES. GIVEN THE
WEAK STEERING WINDS ALOFT STORM MOTION WOULD BE LESS THAN 10 MPH AS
INDICATED IN THE NAM AND GFS. THIS WOULD SUPPORT LOCALLY HEAVY
RAINFALL BUT NOT ON A GROSS SCALE AS OFTEN OCCURS IN JULY AND AUGUST
WHEN THE PRECIPITABLE WATER INCREASES TO 1.5 INCHES OR HIGHER.
THE TSTMS SHOULD FOCUS ACROSS NCNTL NEB NEAR OR A BIT SOUTH OF
MONDAYS DEVELOPMENT. THE MODEL CONSENSUS INDICATED THEDFORD SOUTH
AND EAST THRU CUSTER COUNTY AND AREAS NORTH. THE RUC INDICATED
ISOLATED STORMS ACROSS SHERIDAN COUNTY THIS AFTN ALSO WHICH APPEARS
CONSISTENT WITH THE MOISTURE ON THE HIGH PLAINS. THE ONLY PROBLEM
WITH THE FORECAST IS H700MB TEMPS WARM A FEW DEGREES TODAY WHICH
COULD INHIBIT DEVELOPMENT.
THE ATMOSPHERE STABILIZES LATE THIS EVENING. MODEL POPS WERE TIME
SHIFTED 3 HOURS FORWARD AS IT APPEARED STORMS WOULD DEVELOP FROM
21Z-03Z AND COVERAGE WOULD BE ISOLATED TO SCATTERED.
THE TEMPERATURE FORECAST USES THE WARMER GUIDANCE NUMBERS SUPPORTED
BY THE SLIGHT WARMING AT H700MB FOR HIGHS IN THE MID TO UPPER 80S.
THE MIXING HEIGHT MONDAY AFTN AT KLBF WAS 715 MB AND 750 MB AT KUNR.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 316 AM CDT TUE MAY 27 2014
WEDNESDAY AND BEYOND. WARM...SUMMER LIKE TEMPERATURES HEADLINE
THE EXTENDED DISCUSSION INITIALLY...THEN THUNDERSTORM CHANCES
INCREASE LATE WEEK AND NEXT WEEKEND. AMPLIFIED UPPER RIDGING WILL
CONTINUE TO BUILD NORTHEAST FROM THE WESTERN CONUS ACROSS THE
CENTRAL/NORTHERN PLAINS MIDWEEK...WITH A TROUGH MOVING INTO THE
PACIFIC NORTHWEST. THIS UPPER RIDGING WILL DOMINATE THE REGIONAL
WEATHER PATTERN THROUGH AT LEAST EARLY FRIDAY...BEFORE SHOWING
SIGNS OF A BREAKDOWN WITH THE APPROACH/ESTABLISHMENT OF THE
WESTERN CONUS TROUGH. RAIN CHANCES LOOK TO REMAIN NIL THROUGH
EARLY FRIDAY FOR THE CWA. TEMPERATURES WILL BE WARM AS A 587DM
UPPER HIGH BUILDS ACROSS THE PLAINS. GUIDANCE SUGGESTS SFC
TEMPERATURES WEDNESDAY...THURSDAY AND FRIDAY...WELL INTO THE
80S/LOWER 90S...WITH LOWS GENERALLY IN THE 50S AND LOWER 60S. FOR
LATE WEEK AND THE WEEKEND...UPPER LEVEL RIDGE AXIS WILL SHIFT EAST
OF THE MISSOURI VALLEY...PLACING THE ROCKIES AND ADJACENT HIGH
PLAINS UNDER SOUTHWEST FLOW ALOFT. WITH THE PLACEMENT OF THE RIDGE
STILL WITHIN THE REGION...MOST OF THE CWA SHOULD BE DRY FRIDAY
AFTERNOON...HOWEVER WILL CONTINUE TO CARRY 20-40% POPS ACROSS OUR
WEST /GENERALLY WEST OF HIGHWAY 61/ AS ENHANCED UPPER LEVEL JET
ENERGY PASSES THROUGH SW FLOW ALOFT. FOR THE WEEKEND...A NORTHERN
PLAINS SHORTWAVE WILL EJECT FROM THE PARENT WESTERN CONUS TROUGH
AND HELP INCREASE THUNDERSTORM CHANCES. THERE REMAINS TIMING AND
LOCATIONAL DIFFERENCES OF ANY PROJECTED BOUNDARY TO FOCUS THESE
STORMS...SO ATTM WON/T VENTURE AWAY FROM THE ALLBLEND PROCEDURE
WHICH RESPONDED WITH 40% POPS AND LESS FOR THE ENTIRE WEEKEND.
THIS SEEMS REASONABLE. WITH MODEST INSTABILITY IN PLACE...A FEW
STRONG STORMS WILL BE POSSIBLE...HOWEVER SHEAR VALUES ARE WEAK
UNTIL SUNDAY...SO SVR CHANCES ARE LOW INITIALLY...BUT MAY INCREASE
LATE WEEKEND. TEMPERATURES FOR THE WEEKEND WILL BE SLIGHTLY
COOLER...BUT SHOULD REMAIN ABOVE SEASONAL NORMS BY SEVERAL DEGREES
FOR MOST PLACES. INTO EARLY NEXT WEEK...INCREASING OMEGA
ASSOCIATED WITH THE EASTWARD ADVANCE OF A PIECE OF THE WESTERN
CONUS TROUGH WILL PROVIDE FOR STORM CHANCES THROUGH NEXT
TUESDAY....BUT AGAIN THIS WILL BE DEPENDENT ON THE LOCATION OF
BOUNDARIES.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON)
ISSUED AT 1238 PM CDT TUE MAY 27 2014
WEAK FLOW WILL BE ONGOING THROUGH WEDNESDAY MORNING...WHICH WILL
KEEP WINDS LIGHT AND VARIABLE MUCH OF TODAY AND TONIGHT BEFORE
SWITCHING PRIMARILY TO THE SOUTH LATE WEDNESDAY MORNING. DAYTIME
CUMULUS CLOUDS WILL BE SEEN ACROSS MUCH OF WESTERN AND NORTH
CENTRAL NEBRASKA AND THERE IS A CHANCE FOR ISOLATED TO SCATTERED
SHOWERS AND THUNDERSTORMS THIS AFTERNOON EAST OF A LINE FROM KLBF
TO KANW AS WELL AS OVER THE NORTHERN PANHANDLE ALONG AND WEST OF A
LINE FROM KAIA TO KIEN. CONFIDENCE ON COVERAGE OF ANY ACTIVITY
DEVELOPING OVER EITHER TERMINAL IS LOW SO HELD OFF FROM INCLUDING
IN THE FORECAST AT THIS TIME.
&&
.LBF WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...BROOKS
SHORT TERM...CDC
LONG TERM...JACOBS
AVIATION...BROOKS
AREA FORECAST DISCUSSION...UPDATED
NWS NORTH PLATTE NE
1034 AM CDT TUE MAY 27 2014
.UPDATE...
ISSUED AT 1033 AM CDT TUE MAY 27 2014
THE FORECAST WAS UPDATED FOR AREAL COVERAGE OF SHOWER AND
THUNDERSTORM CHANCES THIS AFTERNOON. 27.12Z KLBF SOUNDING SHOWED
STEEP LAPSE RATES IN THE MID LEVELS WITH A GOOD AMOUNT OF
INSTABILITY. FORECAST MODELS INDICATE THIS WILL CHANGE LITTLE
THROUGH THE DAY. SO EXPECTING TO GET CUMULUS TO DEVELOP ALONG WITH
SOME SHOWERS AND THUNDERSTORMS THIS AFTERNOON UPON REACHING
SURFACE CONVECTIVE TEMPERATURE. MOISTURE WON/T BE GREAT THOUGH SO
THINKING COVERAGE SHOULD BE LIMITED TO ISOLATED...AND HAVE THE
CHANCES MAINLY OVER THE EASTERN PARTS OF THE FORECAST AREA AND THE
NORTHWEST WHERE THERE WILL BE SLIGHTLY MORE MOISTURE. STEERING
FLOW IS LIGHT...AND DEEP LAYER SHEAR IS MINIMAL SO EXPECTING
GENERALLY SLOW MOVING GARDEN VARIETY TYPE SHOWERS AND STORMS.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 316 AM CDT TUE MAY 27 2014
TODAY AND TONIGHT...THE MODEL CONSENSUS INDICATES GOOD MOISTURE WILL
REMAIN IN PLACE TODAY FOR ADDITIONAL DIURNAL TSTM DEVELOPMENT. WINDS
ALOFT WILL REMAIN WEAK AND CAPE MODEST. K INDICES SHOULD RISE TO
AROUND 35C AND PRECIPITABLE WATER TO 1 TO 1.25 INCHES. GIVEN THE
WEAK STEERING WINDS ALOFT STORM MOTION WOULD BE LESS THAN 10 MPH AS
INDICATED IN THE NAM AND GFS. THIS WOULD SUPPORT LOCALLY HEAVY
RAINFALL BUT NOT ON A GROSS SCALE AS OFTEN OCCURS IN JULY AND AUGUST
WHEN THE PRECIPITABLE WATER INCREASES TO 1.5 INCHES OR HIGHER.
THE TSTMS SHOULD FOCUS ACROSS NCNTL NEB NEAR OR A BIT SOUTH OF
MONDAYS DEVELOPMENT. THE MODEL CONSENSUS INDICATED THEDFORD SOUTH
AND EAST THRU CUSTER COUNTY AND AREAS NORTH. THE RUC INDICATED
ISOLATED STORMS ACROSS SHERIDAN COUNTY THIS AFTN ALSO WHICH APPEARS
CONSISTENT WITH THE MOISTURE ON THE HIGH PLAINS. THE ONLY PROBLEM
WITH THE FORECAST IS H700MB TEMPS WARM A FEW DEGREES TODAY WHICH
COULD INHIBIT DEVELOPMENT.
THE ATMOSPHERE STABILIZES LATE THIS EVENING. MODEL POPS WERE TIME
SHIFTED 3 HOURS FORWARD AS IT APPEARED STORMS WOULD DEVELOP FROM
21Z-03Z AND COVERAGE WOULD BE ISOLATED TO SCATTERED.
THE TEMPERATURE FORECAST USES THE WARMER GUIDANCE NUMBERS SUPPORTED
BY THE SLIGHT WARMING AT H700MB FOR HIGHS IN THE MID TO UPPER 80S.
THE MIXING HEIGHT MONDAY AFTN AT KLBF WAS 715 MB AND 750 MB AT KUNR.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 316 AM CDT TUE MAY 27 2014
WEDNESDAY AND BEYOND. WARM...SUMMER LIKE TEMPERATURES HEADLINE
THE EXTENDED DISCUSSION INITIALLY...THEN THUNDERSTORM CHANCES
INCREASE LATE WEEK AND NEXT WEEKEND. AMPLIFIED UPPER RIDGING WILL
CONTINUE TO BUILD NORTHEAST FROM THE WESTERN CONUS ACROSS THE
CENTRAL/NORTHERN PLAINS MIDWEEK...WITH A TROUGH MOVING INTO THE
PACIFIC NORTHWEST. THIS UPPER RIDGING WILL DOMINATE THE REGIONAL
WEATHER PATTERN THROUGH AT LEAST EARLY FRIDAY...BEFORE SHOWING
SIGNS OF A BREAKDOWN WITH THE APPROACH/ESTABLISHMENT OF THE
WESTERN CONUS TROUGH. RAIN CHANCES LOOK TO REMAIN NIL THROUGH
EARLY FRIDAY FOR THE CWA. TEMPERATURES WILL BE WARM AS A 587DM
UPPER HIGH BUILDS ACROSS THE PLAINS. GUIDANCE SUGGESTS SFC
TEMPERATURES WEDNESDAY...THURSDAY AND FRIDAY...WELL INTO THE
80S/LOWER 90S...WITH LOWS GENERALLY IN THE 50S AND LOWER 60S. FOR
LATE WEEK AND THE WEEKEND...UPPER LEVEL RIDGE AXIS WILL SHIFT EAST
OF THE MISSOURI VALLEY...PLACING THE ROCKIES AND ADJACENT HIGH
PLAINS UNDER SOUTHWEST FLOW ALOFT. WITH THE PLACEMENT OF THE RIDGE
STILL WITHIN THE REGION...MOST OF THE CWA SHOULD BE DRY FRIDAY
AFTERNOON...HOWEVER WILL CONTINUE TO CARRY 20-40% POPS ACROSS OUR
WEST /GENERALLY WEST OF HIGHWAY 61/ AS ENHANCED UPPER LEVEL JET
ENERGY PASSES THROUGH SW FLOW ALOFT. FOR THE WEEKEND...A NORTHERN
PLAINS SHORTWAVE WILL EJECT FROM THE PARENT WESTERN CONUS TROUGH
AND HELP INCREASE THUNDERSTORM CHANCES. THERE REMAINS TIMING AND
LOCATIONAL DIFFERENCES OF ANY PROJECTED BOUNDARY TO FOCUS THESE
STORMS...SO ATTM WON/T VENTURE AWAY FROM THE ALLBLEND PROCEDURE
WHICH RESPONDED WITH 40% POPS AND LESS FOR THE ENTIRE WEEKEND.
THIS SEEMS REASONABLE. WITH MODEST INSTABILITY IN PLACE...A FEW
STRONG STORMS WILL BE POSSIBLE...HOWEVER SHEAR VALUES ARE WEAK
UNTIL SUNDAY...SO SVR CHANCES ARE LOW INITIALLY...BUT MAY INCREASE
LATE WEEKEND. TEMPERATURES FOR THE WEEKEND WILL BE SLIGHTLY
COOLER...BUT SHOULD REMAIN ABOVE SEASONAL NORMS BY SEVERAL DEGREES
FOR MOST PLACES. INTO EARLY NEXT WEEK...INCREASING OMEGA
ASSOCIATED WITH THE EASTWARD ADVANCE OF A PIECE OF THE WESTERN
CONUS TROUGH WILL PROVIDE FOR STORM CHANCES THROUGH NEXT
TUESDAY....BUT AGAIN THIS WILL BE DEPENDENT ON THE LOCATION OF
BOUNDARIES.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z WEDNESDAY MORNING)
ISSUED AT 605 AM CDT TUE MAY 27 2014
VFR IS GENERALLY EXPECTED ALL AREAS TODAY AND TONIGHT.
THE MODEL CONSENSUS INDICATES ISOLATED SHRA/TSTM DEVELOPMENT 21Z-
03Z TODAY ACROSS TWO MAIN AREAS. 1...ACROSS THE ERN NEB PANHANDLE
NORTH OF I-80 AND 2...EAST OF KTIF THROUGH KBBW-KONL. STORM
ACTIVITY SHOULD DISSIPATE WITH THE LOSS OF HEATING AROUND 03Z.
&&
.LBF WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...BROOKS
SHORT TERM...CDC
LONG TERM...JACOBS
AVIATION...CDC
AREA FORECAST DISCUSSION...UPDATED
NWS NORTH PLATTE NE
608 AM CDT TUE MAY 27 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 316 AM CDT TUE MAY 27 2014
TODAY AND TONIGHT...THE MODEL CONSENSUS INDICATES GOOD MOISTURE WILL
REMAIN IN PLACE TODAY FOR ADDITIONAL DIURNAL TSTM DEVELOPMENT. WINDS
ALOFT WILL REMAIN WEAK AND CAPE MODEST. K INDICES SHOULD RISE TO
AROUND 35C AND PRECIPITABLE WATER TO 1 TO 1.25 INCHES. GIVEN THE
WEAK STEERING WINDS ALOFT STORM MOTION WOULD BE LESS THAN 10 MPH AS
INDICATED IN THE NAM AND GFS. THIS WOULD SUPPORT LOCALLY HEAVY
RAINFALL BUT NOT ON A GROSS SCALE AS OFTEN OCCURS IN JULY AND AUGUST
WHEN THE PRECIPITABLE WATER INCREASES TO 1.5 INCHES OR HIGHER.
THE TSTMS SHOULD FOCUS ACROSS NCNTL NEB NEAR OR A BIT SOUTH OF
MONDAYS DEVELOPMENT. THE MODEL CONSENSUS INDICATED THEDFORD SOUTH
AND EAST THRU CUSTER COUNTY AND AREAS NORTH. THE RUC INDICATED
ISOLATED STORMS ACROSS SHERIDAN COUNTY THIS AFTN ALSO WHICH APPEARS
CONSISTENT WITH THE MOISTURE ON THE HIGH PLAINS. THE ONLY PROBLEM
WITH THE FORECAST IS H700MB TEMPS WARM A FEW DEGREES TODAY WHICH
COULD INHIBIT DEVELOPMENT.
THE ATMOSPHERE STABILIZES LATE THIS EVENING. MODEL POPS WERE TIME
SHIFTED 3 HOURS FORWARD AS IT APPEARED STORMS WOULD DEVELOP FROM
21Z-03Z AND COVERAGE WOULD BE ISOLATED TO SCATTERED.
THE TEMPERATURE FORECAST USES THE WARMER GUIDANCE NUMBERS SUPPORTED
BY THE SLIGHT WARMING AT H700MB FOR HIGHS IN THE MID TO UPPER 80S.
THE MIXING HEIGHT MONDAY AFTN AT KLBF WAS 715 MB AND 750 MB AT KUNR.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 316 AM CDT TUE MAY 27 2014
WEDNESDAY AND BEYOND. WARM...SUMMER LIKE TEMPERATURES HEADLINE
THE EXTENDED DISCUSSION INITIALLY...THEN THUNDERSTORM CHANCES
INCREASE LATE WEEK AND NEXT WEEKEND. AMPLIFIED UPPER RIDGING WILL
CONTINUE TO BUILD NORTHEAST FROM THE WESTERN CONUS ACROSS THE
CENTRAL/NORTHERN PLAINS MIDWEEK...WITH A TROUGH MOVING INTO THE
PACIFIC NORTHWEST. THIS UPPER RIDGING WILL DOMINATE THE REGIONAL
WEATHER PATTERN THROUGH AT LEAST EARLY FRIDAY...BEFORE SHOWING
SIGNS OF A BREAKDOWN WITH THE APPROACH/ESTABLISHMENT OF THE
WESTERN CONUS TROUGH. RAIN CHANCES LOOK TO REMAIN NIL THROUGH
EARLY FRIDAY FOR THE CWA. TEMPERATURES WILL BE WARM AS A 587DM
UPPER HIGH BUILDS ACROSS THE PLAINS. GUIDANCE SUGGESTS SFC
TEMPERATURES WEDNESDAY...THURSDAY AND FRIDAY...WELL INTO THE
80S/LOWER 90S...WITH LOWS GENERALLY IN THE 50S AND LOWER 60S. FOR
LATE WEEK AND THE WEEKEND...UPPER LEVEL RIDGE AXIS WILL SHIFT EAST
OF THE MISSOURI VALLEY...PLACING THE ROCKIES AND ADJACENT HIGH
PLAINS UNDER SOUTHWEST FLOW ALOFT. WITH THE PLACEMENT OF THE RIDGE
STILL WITHIN THE REGION...MOST OF THE CWA SHOULD BE DRY FRIDAY
AFTERNOON...HOWEVER WILL CONTINUE TO CARRY 20-40% POPS ACROSS OUR
WEST /GENERALLY WEST OF HIGHWAY 61/ AS ENHANCED UPPER LEVEL JET
ENERGY PASSES THROUGH SW FLOW ALOFT. FOR THE WEEKEND...A NORTHERN
PLAINS SHORTWAVE WILL EJECT FROM THE PARENT WESTERN CONUS TROUGH
AND HELP INCREASE THUNDERSTORM CHANCES. THERE REMAINS TIMING AND
LOCATIONAL DIFFERENCES OF ANY PROJECTED BOUNDARY TO FOCUS THESE
STORMS...SO ATTM WON/T VENTURE AWAY FROM THE ALLBLEND PROCEDURE
WHICH RESPONDED WITH 40% POPS AND LESS FOR THE ENTIRE WEEKEND.
THIS SEEMS REASONABLE. WITH MODEST INSTABILITY IN PLACE...A FEW
STRONG STORMS WILL BE POSSIBLE...HOWEVER SHEAR VALUES ARE WEAK
UNTIL SUNDAY...SO SVR CHANCES ARE LOW INITIALLY...BUT MAY INCREASE
LATE WEEKEND. TEMPERATURES FOR THE WEEKEND WILL BE SLIGHTLY
COOLER...BUT SHOULD REMAIN ABOVE SEASONAL NORMS BY SEVERAL DEGREES
FOR MOST PLACES. INTO EARLY NEXT WEEK...INCREASING OMEGA
ASSOCIATED WITH THE EASTWARD ADVANCE OF A PIECE OF THE WESTERN
CONUS TROUGH WILL PROVIDE FOR STORM CHANCES THROUGH NEXT
TUESDAY....BUT AGAIN THIS WILL BE DEPENDENT ON THE LOCATION OF
BOUNDARIES.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z WEDNESDAY MORNING)
ISSUED AT 605 AM CDT TUE MAY 27 2014
VFR IS GENERALLY EXPECTED ALL AREAS TODAY AND TONIGHT.
THE MODEL CONSENSUS INDICATES ISOLATED SHRA/TSTM DEVELOPMENT 21Z-
03Z TODAY ACROSS TWO MAIN AREAS. 1...ACROSS THE ERN NEB PANHANDLE
NORTH OF I-80 AND 2...EAST OF KTIF THROUGH KBBW-KONL. STORM
ACTIVITY SHOULD DISSIPATE WITH THE LOSS OF HEATING AROUND 03Z.
&&
.LBF WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...CDC
LONG TERM...JACOBS
AVIATION...CDC
AREA FORECAST DISCUSSION
NWS NORTH PLATTE NE
316 AM CDT TUE MAY 27 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 316 AM CDT TUE MAY 27 2014
TODAY AND TONIGHT...THE MODEL CONSENSUS INDICATES GOOD MOISTURE WILL
REMAIN IN PLACE TODAY FOR ADDITIONAL DIURNAL TSTM DEVELOPMENT. WINDS
ALOFT WILL REMAIN WEAK AND CAPE MODEST. K INDICES SHOULD RISE TO
AROUND 35C AND PRECIPITABLE WATER TO 1 TO 1.25 INCHES. GIVEN THE
WEAK STEERING WINDS ALOFT STORM MOTION WOULD BE LESS THAN 10 MPH AS
INDICATED IN THE NAM AND GFS. THIS WOULD SUPPORT LOCALLY HEAVY
RAINFALL BUT NOT ON A GROSS SCALE AS OFTEN OCCURS IN JULY AND AUGUST
WHEN THE PRECIPITABLE WATER INCREASES TO 1.5 INCHES OR HIGHER.
THE TSTMS SHOULD FOCUS ACROSS NCNTL NEB NEAR OR A BIT SOUTH OF
MONDAYS DEVELOPMENT. THE MODEL CONSENSUS INDICATED THEDFORD SOUTH
AND EAST THRU CUSTER COUNTY AND AREAS NORTH. THE RUC INDICATED
ISOLATED STORMS ACROSS SHERIDAN COUNTY THIS AFTN ALSO WHICH APPEARS
CONSISTENT WITH THE MOISTURE ON THE HIGH PLAINS. THE ONLY PROBLEM
WITH THE FORECAST IS H700MB TEMPS WARM A FEW DEGREES TODAY WHICH
COULD INHIBIT DEVELOPMENT.
THE ATMOSPHERE STABILIZES LATE THIS EVENING. MODEL POPS WERE TIME
SHIFTED 3 HOURS FORWARD AS IT APPEARED STORMS WOULD DEVELOP FROM
21Z-03Z AND COVERAGE WOULD BE ISOLATED TO SCATTERED.
THE TEMPERATURE FORECAST USES THE WARMER GUIDANCE NUMBERS SUPPORTED
BY THE SLIGHT WARMING AT H700MB FOR HIGHS IN THE MID TO UPPER 80S.
THE MIXING HEIGHT MONDAY AFTN AT KLBF WAS 715 MB AND 750 MB AT KUNR.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 316 AM CDT TUE MAY 27 2014
WEDNESDAY AND BEYOND. WARM...SUMMER LIKE TEMPERATURES HEADLINE
THE EXTENDED DISCUSSION INITIALLY...THEN THUNDERSTORM CHANCES
INCREASE LATE WEEK AND NEXT WEEKEND. AMPLIFIED UPPER RIDGING WILL
CONTINUE TO BUILD NORTHEAST FROM THE WESTERN CONUS ACROSS THE
CENTRAL/NORTHERN PLAINS MIDWEEK...WITH A TROUGH MOVING INTO THE
PACIFIC NORTHWEST. THIS UPPER RIDGING WILL DOMINATE THE REGIONAL
WEATHER PATTERN THROUGH AT LEAST EARLY FRIDAY...BEFORE SHOWING
SIGNS OF A BREAKDOWN WITH THE APPROACH/ESTABLISHMENT OF THE
WESTERN CONUS TROUGH. RAIN CHANCES LOOK TO REMAIN NIL THROUGH
EARLY FRIDAY FOR THE CWA. TEMPERATURES WILL BE WARM AS A 587DM
UPPER HIGH BUILDS ACROSS THE PLAINS. GUIDANCE SUGGESTS SFC
TEMPERATURES WEDNESDAY...THURSDAY AND FRIDAY...WELL INTO THE
80S/LOWER 90S...WITH LOWS GENERALLY IN THE 50S AND LOWER 60S. FOR
LATE WEEK AND THE WEEKEND...UPPER LEVEL RIDGE AXIS WILL SHIFT EAST
OF THE MISSOURI VALLEY...PLACING THE ROCKIES AND ADJACENT HIGH
PLAINS UNDER SOUTHWEST FLOW ALOFT. WITH THE PLACEMENT OF THE RIDGE
STILL WITHIN THE REGION...MOST OF THE CWA SHOULD BE DRY FRIDAY
AFTERNOON...HOWEVER WILL CONTINUE TO CARRY 20-40% POPS ACROSS OUR
WEST /GENERALLY WEST OF HIGHWAY 61/ AS ENHANCED UPPER LEVEL JET
ENERGY PASSES THROUGH SW FLOW ALOFT. FOR THE WEEKEND...A NORTHERN
PLAINS SHORTWAVE WILL EJECT FROM THE PARENT WESTERN CONUS TROUGH
AND HELP INCREASE THUNDERSTORM CHANCES. THERE REMAINS TIMING AND
LOCATIONAL DIFFERENCES OF ANY PROJECTED BOUNDARY TO FOCUS THESE
STORMS...SO ATTM WON/T VENTURE AWAY FROM THE ALLBLEND PROCEDURE
WHICH RESPONDED WITH 40% POPS AND LESS FOR THE ENTIRE WEEKEND.
THIS SEEMS REASONABLE. WITH MODEST INSTABILITY IN PLACE...A FEW
STRONG STORMS WILL BE POSSIBLE...HOWEVER SHEAR VALUES ARE WEAK
UNTIL SUNDAY...SO SVR CHANCES ARE LOW INITIALLY...BUT MAY INCREASE
LATE WEEKEND. TEMPERATURES FOR THE WEEKEND WILL BE SLIGHTLY
COOLER...BUT SHOULD REMAIN ABOVE SEASONAL NORMS BY SEVERAL DEGREES
FOR MOST PLACES. INTO EARLY NEXT WEEK...INCREASING OMEGA
ASSOCIATED WITH THE EASTWARD ADVANCE OF A PIECE OF THE WESTERN
CONUS TROUGH WILL PROVIDE FOR STORM CHANCES THROUGH NEXT
TUESDAY....BUT AGAIN THIS WILL BE DEPENDENT ON THE LOCATION OF
BOUNDARIES.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT)
ISSUED AT 1222 AM CDT TUE MAY 27 2014
ISOLATED SHOWERS AND THUNDERSTORMS IN CENTRAL AND NORTH CENTRAL
NEBRASKA WILL CONTINUE THROUGH TONIGHT IN CENTRAL AND NORTHE CENTRAL
NEBRASKA. AT THIS TIME...IT DOES NOT APPEAR THAT ANY ORGANIZED
PRECIPITATION SYSTEM WILL DEVELOP.
OTHERWISE...LIGHT WIND AND VISUAL METEOROLOGICAL CONDITIONS WILL
CONTINUE IN CENTRAL AND WESTERN NEBRASKA TONIGHT THROUGH TUESDAY.
&&
.LBF WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...CDC
LONG TERM...JACOBS
AVIATION...CDC
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
719 PM EDT WED MAY 28 2014
.SYNOPSIS...
HIGH PRESSURE OVER NEW ENGLAND WILL PROVIDE FAIR WEATHER FOR
TOMORROW. A WEAK COLD FRONT WILL BRING SCATTERED SHOWERS TO THE
AREA ON FRIDAY PRIMARILY EAST OF INTERSTATE 81. THE WEEKEND WILL
BE DRY WITH MODERATING TEMPERATURES.
&&
.NEAR TERM /UNTIL 6 AM THURSDAY MORNING/...
700 PM EDT UPDATE...
NO SIGNIFICANT CHANGES WERE MADE TO THE FORECAST.
PREVIOUS FORECAST....
345 PM UPDATE...
MOSTLY CLOUDY SKIES RESIDE OVER THE FINGER LAKES REGION EAST TO
THE WESTERN MOHAWK VALLEY AND SOUTH THROUGH THE CATSKILLS AND
POCONOS. REST OF THE AREA IS BASKING IN PARTLY SUNNY SKIES.
FOR TONIGHT, SFC HIGH PRES OVER NRN NEW ENGLAND WILL GRADUALLY
BUILD SOUTH. A MOIST E/SE FLOW WILL PERSIST OVERNIGHT BRINGING
STRATUS AND PATCHY DRIZZLE OVER NORTHEAST PENNSYLVANIA AND THE
SOUTHERN TIER. TOWARD DAYBREAK LOW LEVEL DRYING WILL OCCUR IN
THE WESTERN MOHAWK AND CHERRY VALLEY AREA WITH SOME CLEARING
EXPECTED. OVERNIGHT LOWS WILL RANGE IN THE LOWER 40S TO AROUND 50.
&&
.SHORT TERM /6 AM THURSDAY MORNING THROUGH SATURDAY/...
THURSDAY...SFC HIGH PRES WILL RESIDE ALONG THE NEW ENGLAND COAST
AND PROVIDE A COOL SOUTHEAST FLOW ACROSS THE REGION. PARTLY SUNNY
SKIES WILL BECOME MORE WIDESPREAD THAN TODAY AS SOME LOW LEVEL
DRYING OCCURS BUT THE MORNING HOURS WILL STILL BE PRIMARILY MOSTLY
CLOUDY. MAX TEMPS WILL GENERALLY RANGE IN THE MID TO UPPER 60S.
THURSDAY NIGHT/FRIDAY...H5 TROF AND ASSOCIATED SHORT WAVES WILL
MOVE THROUGH THE NORTHEAST AS A WEAK SFC TROF PASSES FRIDAY
MORNING. THE CHANCE FOR SHOWERS WILL INCREASE TOWARD DAYBREAK
FRIDAY WITH HIGHEST POPS OVER ERN PTN OF FA. BY MIDDAY FRIDAY
WILL CONTINUE WITH HIGH CHC POPS CATSKILLS AND SLIGHT CHANCE OVER
THE EASTERN FINGER LAKES REGION. MODEL SOUNDINGS SHOW SEVERAL
HUNDRED J/KG OF CAPE SO WILL CONTINUE MENTION OF ISOLATED TRW EAST
OF I81.
FRIDAY NIGHT/SATURDAY...H5 LOW WILL DROP SOUTH FROM NOVA SCOTIA
TO WELL OFF COASTAL NEW ENGLAND. HIGH PRES WILL GRADUALLY BUILD
EAST FROM THE WESTERN LAKES. PERIOD WILL BE DRY BUT RATHER BREEZY
WITH SEASONAL TEMPERATURES.
&&
.LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/...
BEAUTIFUL WEATHER EXPECTED AT THE START OF THE PERIOD AS A STRONG
RIDGE OF HIGH PRESSURE REMAINS PARKED OVER THE AREA. WITH 500-HPA
HEIGHTS EXPECTED TO BUILD TO APPROXIMATELY 584-DM...AFTERNOON
TEMPS BOTH SUNDAY AND MONDAY LOOK TO WARM INTO THE UPPER 70S TO
LWR 80S...WITH POTENTIALLY WARMER VALUES NOT OUT OF THE QUESTION.
HEADING INTO EARLY NEXT WEEK...FCST BECOMES A BIT MORE CHALLENGING
AS ALL EXTENDED GUIDANCE THIS AFTERNOON SHOWS A SOUTHWARD SAGGING
COLD FRONT WHICH WILL BE HEADING OUR WAY FROM EASTERN CANADA BY
MIDWEEK. BEFORE THIS HOWEVER...A WARM FRONT WILL LIFT NORTHEAST
FROM THE OHIO VLY WHICH BY MONDAY WHICH WILL LIKELY LEAD TO THE
FIRST ROUND OF SHWRS/STORMS AS EARLY AS MONDAY AFTERNOON. MAIN
CONCERN FROM THIS VANTAGE POINT IS THE MODEL/S FORECAST OF VERY
HIGH PWAT VALUES /I.E. CLOSE TO 2.00"/ WHICH COULD LEAD TO A
HEAVY RAIN CONCERN THROUGH MIDWEEK...ESPECIALLY AS SECONDARY FRONT
FROM SOUTHERN CANADA ARRIVES. FOR NOW...WILL MAINTAIN CHC POPS
THROUGH THE CONCLUSION OF THE FCST PERIOD.
&&
.AVIATION /23Z WEDNESDAY THROUGH MONDAY/...
USED COMBINATION OF RAP AND LOCAL WRF TO FORECAST THE LOW STRATUS
MARINE LAYER PROGGED TO SLIDE FROM EAST TO WEST OVERNIGHT. THINK
THIS AIRMASS WILL RESULT IN MAINLY MVFR CEILINGS, THOUGH THE
HIGHER BGM ELEVATION WILL HAVE A STRONG SHOT AT IFR.
CLOUDS WILL BURN OFF BETWEEN LATE MORNING AND EARLY AFTERNOON ON
THURSDAY. VFR CONDITIONS ARE FORECAST FOR ALL TERMINALS.
OUTLOOK...
FRI...BRIEF RESTRICTIONS POSSIBLE IN DEVELOPING SHWRS.
FRI NGT THROUGH SUNDAY...MAINLY VFR...HOWEVER EARLY MORNING
RESTRICTIONS POSSIBLE AT ELM IN VALLEY FOG.
MON/TUE...RESTRICTIONS POSSIBLE IN DEVELOPING SHWRS/STORMS.
&&
.BGM WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NY...NONE.
&&
$$
SYNOPSIS...RRM
NEAR TERM...KAH/RRM
SHORT TERM...RRM
LONG TERM...CMG
AVIATION...DJP
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
155 PM EDT TUE MAY 27 2014
.SYNOPSIS...
A FRONTAL SYSTEM WILL DROP INTO NY STATE, AND KEEP OUR WEATHER
UNSETTLED THROUGH WEDNESDAY WITH THE CHANCE FOR SHOWERS AND
THUNDERSTORMS. HIGH PRESSURE WILL BRING FAIR WEATHER FOR THURSDAY,
BEFORE A WEAK FRONT BRINGS A FEW SHOWERS TO THE REGION EARLY
FRIDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
1256 PM UPDATE...
MORE INSTABILITY THAN ORIGINALLY EXPECTED HAS DEVELOPED. MLCAPES
ARE IN THE 1000 J/KG RANGE, WITH A SLIM WEDGE OF 150-200 0-3KM SRH
VALUES DEVELOPING AHEAD OF ONCOMING THUNDERSTORM CLUSTER. HAVE
UPGRADED THE THUNDER POTENTIAL IN THE GRIDS, AND UPDATED THE HWO
AND GRAPHICAL HWO PRODUCTS.
1041 AM UPDATE...
REORGANIZED POP GRIDS TODAY TO FOCUS LIKELY POPS MAINLY ALONG THE
NY/PA BORDER SOUTHWARD, WHERE THE INSTABILITY AND MOISTURE WILL BE
HIGHEST TODAY. TAPERED OFF TO CHANCE POPS TO THE NORTH.
CAPES IN THE 600-800 J/KG RANGE WILL COMBINE WITH A LOW FLOW WIND
FIELD, SUGGESTING LITTLE TO NO SEVERE THREAT. MORE INTERESTING IS
THE 1.50+ PWAT. GIVEN MBE VELOCITIES OF 4 TO 8 KTS, THERE IS
POTENTIAL FOR HEAVY RAIN AND EVEN SOME TRAINING. PEAK TIME FOR
CONVECTION IS BETWEEN 18Z AND 00Z.
640 AM UPDATE...
RISING DWPTS AND EXTENSIVE CLD CVR DID NOT ALLOW TEMPS TO DROP OFF
MUCH AT ALL THIS MRNG ACRS THE MOHAWK VLY/FINGER LKS WITH SYR
STILL UP ARND 70F. A FEW RENEGADE SHOWERS COURTESY OF A SUBTLE
S/WV IN NW FLOW ARE HEADING TWD ALBANY AT THIS TIME BUT HAD TO
EXPAND 20 POPS FURTHER TO THE EAST TO ACCNT FOR THESE THIS MRNG.
EXPECT A MORE PROMINENT BATCH OF SHRA/TSRA TO DVLP AFT 17Z IN
INCRSGLY MOIST FLOW AHD OF SLOW-MVG CLD FRONT.
PREV DISCO BLO...
255 AM UPDATE...
A WK S/WV IS SPARKING OFF A FEW SPRINKLES IN FINGER LKS REGION.
THESE SPRINKLES ARE FALLING OUT OF AN OVERCAST MID-DECK SO NOT
EXPECTING THEM TO AMNT TO MUCH BFR 12Z. AFT 12Z, PW VALUES WL INCRS
TO > 1.30 INCHES WHICH IS APPCHG 2 SD ABV NORMAL FOR THIS TIME OF
YR. LATEST RUC GUIDANCE APPEARS TO BE RIGHT ON TARGET WITH BLENDED
TPW PRODUCT AS OF 06Z, WITH AMNTS < 1 INCH ACRS CWA WITH PW VALUES
NEARING 1.40 INCHES IN NWPA. EXPECT HIGHER PW VALUES TO HEAD EAST
AND INTO AREA THIS AFTN WITH AMNTS BTWN 2-3 SD ABV NORMAL APPCHG
1.60 INCHES.
SFC LOPRES SITTING ALONG ONTARIO/QUEBEC BORDER WITH SFC BNDRYS
EXTNDG EAST AND WEST FM CENTER. THIS LOW DRIFTS SOUTH TDA AND ALL
MODELS BUT THE GFS AGREE ON PLACEMENT OF LOW CNTR OVR SERN ONTARIO
AS OF 18Z THIS AFTN. MAIN CDFNT WL BE LOCATED ACRS SRN PORTIONS OF
ONTARIO BACK INTO LWR MICHIGAN WHILE A BACKDOOR-TYPE COLD FRONT WL
BE PUSHING IN FM NEW ENGLAND LATE AFTN/EVNG HRS AS STRONG HIPRES
BUILDS DOWN INTO THE CANADIAN MARITIMES.
WHILE PW VALUES WL BE ANONYMOUSLY HIGH CORFIDI VECTORS PROGGED TO BE
ARND 10KTS DRG THE DAY. EVEN THO WINDS WL BE RELATIVELY LGT, STILL
SEEMS THAT THERE WL BE ENUF FLOW TO KEEP STORMS MVG TO PREVENT
THREAT FOR MAJOR FLASH FLOODING. CANNOT RULE OUT LOCALLY HEAVY
DOWNPOURS IN STORMS THAT ARE ABLE TO DVLP DUE TO SATD ATMOSPHERE IN
PLACE AND WL WORD AS SUCH IN HWO. CAPE VALUES WL BE TALL AND SKINNY
AND RANGE FM 500-1000 J/KG, THUS POTENTIAL ALSO EXISTS FOR SMALL
HAIL. WITH VRY LITTLE DRY AIR ALOFT EXPECTED TO WORK IN THIS AFTN,
LOOKING AT A LESSOR WIND THREAT THAN HAIL.
MAX TEMPS WL FALL A FEW DEGREES SHORT OF YDA`S VALUES AS EXTENSIVE
CLD CVR WL LIMIT SOLAR INSOLATION. HIGHS WL ONLY REACH INTO THE
U70S/ARND 80 ACRS MAJORITY OF CWA THIS AFTN.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH FRIDAY/...
415 AM UPDATE...
BACKDOOR FRONT WL ENCROACH FM THE EAST LATE TONIGHT, KEEPING THE CHC
FOR POPS AND POSSIBLY THUNDER THRU MIDNIGHT AS K-INDICES RMN IN THE
30S AND THEN QUICKLY DIMINISH AFT 04Z AS MID-LVL LAPSE RATES WEAKEN.
DRIER DWPTS AND COOLER MINS EXPECTED ACRS ERN ZONES TONIGHT AS
BACKDOOR FRONT SLIDES IN FM NEW ENGLAND THO LATEST NAM IS CERTAINLY
MORE BULLISH THAN OTHER MED RANGE GUIDANCE SO HV GONE WITH A BLEND
OF NAM, GFS AND EURO FOR T/TD/WINDS AND POPS FOR TONIGHT.
PCPN CHANCES WL WIND DOWN BY LATE AFTN WED AS SFC TROF OVR CWA WL
CONT TO PROVIDE SOURCE OF LIFT WITH DIURNAL HTG, THO POPS WL ONLY
GET AS HIGH AS 50% DRG THE DAY. SFC WINDS WL BE FM THE EAST FOR
AREAS EAST OF THE I-81 CORRIDOR, RESULTING IN COOLER HIGHS FOR WED
AFTN WHILE AREAS TWD THE FINGER LKS WL BE CLOSE TO NRML VALUES WITH
MAXES IN THE 70S.
HIPRES WL THEN BUILD IN FM NEW ENGLAND LATE WED NGT, ALLOWING SKIES
TO BEGIN TO CLR FM EAST TO WEST. COOLER TEMPS WL ACCOMPANY HIGH
PRESSURE AND ERLY FLOW WITH MRNG LOWS DIPPING INTO THE 40S OVR WRN
CATS AND 50S ELSEWHERE. ONLY A LINGERING SHOWER OR TWO IS EXPECTED
WED EVNG AS LACKLUSTER TROF PUSHES OFF TO THE EAST WITH MINIMAL FRCG
EXPECTED.
&&
.LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/...
MEDIUM RANGE MODELS ARE IN FAIR AGREEMENT THROUGH THE EXTENDED
PERIOD. FRIDAY NIGHT THROUGH SUNDAY, A FLAT UPPER LEVEL RIDGE WILL
RESIDE OVER THE AREA AS SFC HIGH PRES MOVES FROM THE VICINITY TO
ALONG THE NEW JERSEY COAST. THESE FEATURES WILL PROVIDE DRY
CONDITIONS ALONG WITH MODIFYING TEMPERATURES.
MONDAY THROUGH TUESDAY, A COLD FRONT WILL DROP SOUTH ACROSS THE
REGION AS SFC LOW PRES TRACKS ACROSS SOUTHERN CANADA. WILL CONTINUE
WITH CHC POPS THROUGH THE PERIOD FOR CONVECTION. TEMPS WILL REMAIN
CLOSE TO SEASONAL.
&&
.AVIATION /18Z TUESDAY THROUGH SUNDAY/...
MODERATE INSTABILITY COMBINED WITH A MOIST AIRMASS WILL LEAD TO
SCATTERED TO WIDESPREAD CONVECTION FROM MID AFTERNOON THROUGH
EARLY EVENING ESPECIALLY OVER THE CENTRAL AND SOUTHERN TERMINALS.
AT KRME/KSYR ONLY INCLUDED UNRESTRICTED SHOWERS THROUGH LATE
AFTERNOON. ELSEWHERE, INCLUDED MVFR THUNDERSTORMS UNTIL 21Z THEN
JUST MVFR RAIN SHOWERS UNTIL 00Z.
OVERNIGHT, A BACK DOOR COLD FRONT WILL APPROACH THE REGION
RESULTING IN LOW LEVEL SATURATION AND UPSLOPE FLOW. AFTER 06Z
GENERALLY INCLUDED MVFR/LOW MVFR CIGS. LIGHT SHOWER OR DRIZZLE MAY
ALSO OCCUR BUT NOT INCLUDED DUE TO LOW PROBABILITY.
WEDNESDAY MORNING CIGS WILL GRADUALLY IMPROVE TO LOW VFR/MVFR.
WESTERLY WINDS AROUND 10 KNOTS BECOMING NORTHWEST AROUND 5 KNOTS
OVERNIGHT THEN N/NE ON WEDNESDAY AT 5-10 KNOTS.
OUTLOOK...
WED NGT/THU...MAINLY VFR.
THU NGT/FRI...RESTRICTIONS POSSIBLE IN SHOWERS. CHANCE TSRA FRI.
FRI NGT THROUGH SUNDAY...VFR.
&&
.BGM WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NY...NONE.
&&
$$
SYNOPSIS...DJP
NEAR TERM...DJP
SHORT TERM...PVN
LONG TERM...RRM
AVIATION...RRM
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
1258 PM EDT TUE MAY 27 2014
.SYNOPSIS...
A FRONTAL SYSTEM WILL DROP INTO NY STATE, AND KEEP OUR WEATHER
UNSETTLED THROUGH WEDNESDAY WITH THE CHANCE FOR SHOWERS AND
THUNDERSTORMS. HIGH PRESSURE WILL BRING FAIR WEATHER FOR THURSDAY,
BEFORE A WEAK FRONT BRINGS A FEW SHOWERS TO THE REGION EARLY
FRIDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
1256 PM UPDATE...
MORE INSTABILITY THAN ORIGINALLY EXPECTED HAS DEVELOPED. MLCAPES
ARE IN THE 1000 J/KG RANGE, WITH A SLIM WEDGE OF 150-200 0-3KM SRH
VALUES DEVELOPING AHEAD OF ONCOMING THUNDERSTORM CLUSTER. HAVE
UPGRADED THE THUNDER POTENTIAL IN THE GRIDS, AND UPDATED THE HWO
AND GRAPHICAL HWO PRODUCTS.
1041 AM UPDATE...
REORGANIZED POP GRIDS TODAY TO FOCUS LIKELY POPS MAINLY ALONG THE
NY/PA BORDER SOUTHWARD, WHERE THE INSTABILITY AND MOISTURE WILL BE
HIGHEST TODAY. TAPERED OFF TO CHANCE POPS TO THE NORTH.
CAPES IN THE 600-800 J/KG RANGE WILL COMBINE WITH A LOW FLOW WIND
FIELD, SUGGESTING LITTLE TO NO SEVERE THREAT. MORE INTERESTING IS
THE 1.50+ PWAT. GIVEN MBE VELOCITIES OF 4 TO 8 KTS, THERE IS
POTENTIAL FOR HEAVY RAIN AND EVEN SOME TRAINING. PEAK TIME FOR
CONVECTION IS BETWEEN 18Z AND 00Z.
640 AM UPDATE...
RISING DWPTS AND EXTENSIVE CLD CVR DID NOT ALLOW TEMPS TO DROP OFF
MUCH AT ALL THIS MRNG ACRS THE MOHAWK VLY/FINGER LKS WITH SYR
STILL UP ARND 70F. A FEW RENEGADE SHOWERS COURTESY OF A SUBTLE
S/WV IN NW FLOW ARE HEADING TWD ALBANY AT THIS TIME BUT HAD TO
EXPAND 20 POPS FURTHER TO THE EAST TO ACCNT FOR THESE THIS MRNG.
EXPECT A MORE PROMINENT BATCH OF SHRA/TSRA TO DVLP AFT 17Z IN
INCRSGLY MOIST FLOW AHD OF SLOW-MVG CLD FRONT.
PREV DISCO BLO...
255 AM UPDATE...
A WK S/WV IS SPARKING OFF A FEW SPRINKLES IN FINGER LKS REGION.
THESE SPRINKLES ARE FALLING OUT OF AN OVERCAST MID-DECK SO NOT
EXPECTING THEM TO AMNT TO MUCH BFR 12Z. AFT 12Z, PW VALUES WL INCRS
TO > 1.30 INCHES WHICH IS APPCHG 2 SD ABV NORMAL FOR THIS TIME OF
YR. LATEST RUC GUIDANCE APPEARS TO BE RIGHT ON TARGET WITH BLENDED
TPW PRODUCT AS OF 06Z, WITH AMNTS < 1 INCH ACRS CWA WITH PW VALUES
NEARING 1.40 INCHES IN NWPA. EXPECT HIGHER PW VALUES TO HEAD EAST
AND INTO AREA THIS AFTN WITH AMNTS BTWN 2-3 SD ABV NORMAL APPCHG
1.60 INCHES.
SFC LOPRES SITTING ALONG ONTARIO/QUEBEC BORDER WITH SFC BNDRYS
EXTNDG EAST AND WEST FM CENTER. THIS LOW DRIFTS SOUTH TDA AND ALL
MODELS BUT THE GFS AGREE ON PLACEMENT OF LOW CNTR OVR SERN ONTARIO
AS OF 18Z THIS AFTN. MAIN CDFNT WL BE LOCATED ACRS SRN PORTIONS OF
ONTARIO BACK INTO LWR MICHIGAN WHILE A BACKDOOR-TYPE COLD FRONT WL
BE PUSHING IN FM NEW ENGLAND LATE AFTN/EVNG HRS AS STRONG HIPRES
BUILDS DOWN INTO THE CANADIAN MARITIMES.
WHILE PW VALUES WL BE ANONYMOUSLY HIGH CORFIDI VECTORS PROGGED TO BE
ARND 10KTS DRG THE DAY. EVEN THO WINDS WL BE RELATIVELY LGT, STILL
SEEMS THAT THERE WL BE ENUF FLOW TO KEEP STORMS MVG TO PREVENT
THREAT FOR MAJOR FLASH FLOODING. CANNOT RULE OUT LOCALLY HEAVY
DOWNPOURS IN STORMS THAT ARE ABLE TO DVLP DUE TO SATD ATMOSPHERE IN
PLACE AND WL WORD AS SUCH IN HWO. CAPE VALUES WL BE TALL AND SKINNY
AND RANGE FM 500-1000 J/KG, THUS POTENTIAL ALSO EXISTS FOR SMALL
HAIL. WITH VRY LITTLE DRY AIR ALOFT EXPECTED TO WORK IN THIS AFTN,
LOOKING AT A LESSOR WIND THREAT THAN HAIL.
MAX TEMPS WL FALL A FEW DEGREES SHORT OF YDA`S VALUES AS EXTENSIVE
CLD CVR WL LIMIT SOLAR INSOLATION. HIGHS WL ONLY REACH INTO THE
U70S/ARND 80 ACRS MAJORITY OF CWA THIS AFTN.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH FRIDAY/...
415 AM UPDATE...
BACKDOOR FRONT WL ENCROACH FM THE EAST LATE TONIGHT, KEEPING THE CHC
FOR POPS AND POSSIBLY THUNDER THRU MIDNIGHT AS K-INDICES RMN IN THE
30S AND THEN QUICKLY DIMINISH AFT 04Z AS MID-LVL LAPSE RATES WEAKEN.
DRIER DWPTS AND COOLER MINS EXPECTED ACRS ERN ZONES TONIGHT AS
BACKDOOR FRONT SLIDES IN FM NEW ENGLAND THO LATEST NAM IS CERTAINLY
MORE BULLISH THAN OTHER MED RANGE GUIDANCE SO HV GONE WITH A BLEND
OF NAM, GFS AND EURO FOR T/TD/WINDS AND POPS FOR TONIGHT.
PCPN CHANCES WL WIND DOWN BY LATE AFTN WED AS SFC TROF OVR CWA WL
CONT TO PROVIDE SOURCE OF LIFT WITH DIURNAL HTG, THO POPS WL ONLY
GET AS HIGH AS 50% DRG THE DAY. SFC WINDS WL BE FM THE EAST FOR
AREAS EAST OF THE I-81 CORRIDOR, RESULTING IN COOLER HIGHS FOR WED
AFTN WHILE AREAS TWD THE FINGER LKS WL BE CLOSE TO NRML VALUES WITH
MAXES IN THE 70S.
HIPRES WL THEN BUILD IN FM NEW ENGLAND LATE WED NGT, ALLOWING SKIES
TO BEGIN TO CLR FM EAST TO WEST. COOLER TEMPS WL ACCOMPANY HIGH
PRESSURE AND ERLY FLOW WITH MRNG LOWS DIPPING INTO THE 40S OVR WRN
CATS AND 50S ELSEWHERE. ONLY A LINGERING SHOWER OR TWO IS EXPECTED
WED EVNG AS LACKLUSTER TROF PUSHES OFF TO THE EAST WITH MINIMAL FRCG
EXPECTED.
&&
.LONG TERM /FRIDAY NIGHT THROUGH MONDAY/...
MEDIUM RANGE MODELS ARE IN FAIR AGREEMENT THROUGH THE EXTENDED
PERIOD. FRIDAY NIGHT THROUGH SUNDAY, A FLAT UPPER LEVEL RIDGE WILL
RESIDE OVER THE AREA AS SFC HIGH PRES MOVES FROM THE VICINITY TO
ALONG THE NEW JERSEY COAST. THESE FEATURES WILL PROVIDE DRY
CONDITIONS ALONG WITH MODIFYING TEMPERATURES.
MONDAY THROUGH TUESDAY, A COLD FRONT WILL DROP SOUTH ACROSS THE
REGION AS SFC LOW PRES TRACKS ACROSS SOUTHERN CANADA. WILL CONTINUE
WITH CHC POPS THROUGH THE PERIOD FOR CONVECTION. TEMPS WILL REMAIN
CLOSE TO SEASONAL.
&&
.AVIATION /18Z TUESDAY THROUGH SUNDAY/...
12Z UPDATE...
MAINLY VFR CONDITIONS EXPECTED THROUGH TODAY BUT WITH SOME BRIEF
MVFR/IFR POSSIBLE THIS AFTERNOON IN DEVELOPING SCT -TSRA AS COLD
FRONT SINKS SOUTH ACROSS THE AREA...AT SAME TIME WEAK WAVES TRAVEL
WNW TO ESE ALOFT. BEST CHANCE FOR CONVECTION WILL BE AS FRONT SAGS
SOUTH OF KSYR-KRME DURING PEAK HEATING AND INSTABILITY...FOR
KBGM-KITH-KELM-KAVP. AS FRONT STALLS...LINGERING SHRA/TSRA WILL BE
POSSIBLE THROUGH EVENING. HAVE HANDLED INITIALLY VIA TEMPO GROUPS
FOR EXPECTED DEVELOPING SCT TSRA EARLY TO MID AFTERNOON...THEN PROB30
TSRA GROUPS INTO A PORTION OF THE EVENING FOR CENTRAL TO SOUTHERN
TERMINALS. FARTHER NORTH...KSYR-KRME LESS CONFIDENCE IN
INSTABILITY BEING REALIZED IN THE FORM OF THUNDER SO LEFT OUT OF
TAFS IN FAVOR ON NON-RESTRICTIVE SHOWERS...BUT AMENDMENTS WILL BE
MADE IF NECESSARY. TONIGHT...EXPECTING SEVERAL TERMINALS TO SLIP
INTO MVFR CIG AS SHALLOW FRONT CONTINUES TO SAG SOUTH...IFR CIG
NOT OUT OF THE QUESTION. ALSO...AREAS THAT GET RAINFALL TODAY MAY
DEVELOP FOG AND/OR LOW STRATUS LATE TONIGHT FROM LEFTOVER
MOISTURE.
OUTLOOK...
WED...RESTRICTIONS POSSIBLE FROM SCT SHRA MAINLY SOUTH OF KSYR-
KRME.
WED NGT/THU...MAINLY VFR.
THU NGT/FRI...RESTRICTIONS POSSIBLE IN SHOWERS. CHANCE TSRA FRI.
FRI NGT/SAT...MAINLY VFR.
&&
.BGM WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NY...NONE.
&&
$$
SYNOPSIS...DJP
NEAR TERM...DJP
SHORT TERM...PVN
LONG TERM...RRM
AVIATION...MDP
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
1215 PM EDT TUE MAY 27 2014
.SYNOPSIS...
A FRONTAL SYSTEM WILL DROP INTO NY STATE, AND KEEP OUR WEATHER
UNSETTLED THROUGH WEDNESDAY WITH THE CHANCE FOR SHOWERS AND
THUNDERSTORMS. HIGH PRESSURE WILL BRING FAIR WEATHER FOR THURSDAY,
BEFORE A WEAK FRONT BRINGS A FEW SHOWERS TO THE REGION EARLY
FRIDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
1041 AM UPDATE...
REORGANIZED POP GRIDS TODAY TO FOCUS LIKELY POPS MAINLY ALONG THE
NY/PA BORDER SOUTHWARD, WHERE THE INSTABILITY AND MOISTURE WILL BE
HIGHEST TODAY. TAPERED OFF TO CHANCE POPS TO THE NORTH.
CAPES IN THE 600-800 J/KG RANGE WILL COMBINE WITH A LOW FLOW WIND
FIELD, SUGGESTING LITTLE TO NO SEVERE THREAT. MORE INTERESTING IS
THE 1.50+ PWAT. GIVEN MBE VELOCITIES OF 4 TO 8 KTS, THERE IS
POTENTIAL FOR HEAVY RAIN AND EVEN SOME TRAINING. PEAK TIME FOR
CONVECTION IS BETWEEN 18Z AND 00Z.
640 AM UPDATE...
RISING DWPTS AND EXTENSIVE CLD CVR DID NOT ALLOW TEMPS TO DROP OFF
MUCH AT ALL THIS MRNG ACRS THE MOHAWK VLY/FINGER LKS WITH SYR
STILL UP ARND 70F. A FEW RENEGADE SHOWERS COURTESY OF A SUBTLE
S/WV IN NW FLOW ARE HEADING TWD ALBANY AT THIS TIME BUT HAD TO
EXPAND 20 POPS FURTHER TO THE EAST TO ACCNT FOR THESE THIS MRNG.
EXPECT A MORE PROMINENT BATCH OF SHRA/TSRA TO DVLP AFT 17Z IN
INCRSGLY MOIST FLOW AHD OF SLOW-MVG CLD FRONT.
PREV DISCO BLO...
255 AM UPDATE...
A WK S/WV IS SPARKING OFF A FEW SPRINKLES IN FINGER LKS REGION.
THESE SPRINKLES ARE FALLING OUT OF AN OVERCAST MID-DECK SO NOT
EXPECTING THEM TO AMNT TO MUCH BFR 12Z. AFT 12Z, PW VALUES WL INCRS
TO > 1.30 INCHES WHICH IS APPCHG 2 SD ABV NORMAL FOR THIS TIME OF
YR. LATEST RUC GUIDANCE APPEARS TO BE RIGHT ON TARGET WITH BLENDED
TPW PRODUCT AS OF 06Z, WITH AMNTS < 1 INCH ACRS CWA WITH PW VALUES
NEARING 1.40 INCHES IN NWPA. EXPECT HIGHER PW VALUES TO HEAD EAST
AND INTO AREA THIS AFTN WITH AMNTS BTWN 2-3 SD ABV NORMAL APPCHG
1.60 INCHES.
SFC LOPRES SITTING ALONG ONTARIO/QUEBEC BORDER WITH SFC BNDRYS
EXTNDG EAST AND WEST FM CENTER. THIS LOW DRIFTS SOUTH TDA AND ALL
MODELS BUT THE GFS AGREE ON PLACEMENT OF LOW CNTR OVR SERN ONTARIO
AS OF 18Z THIS AFTN. MAIN CDFNT WL BE LOCATED ACRS SRN PORTIONS OF
ONTARIO BACK INTO LWR MICHIGAN WHILE A BACKDOOR-TYPE COLD FRONT WL
BE PUSHING IN FM NEW ENGLAND LATE AFTN/EVNG HRS AS STRONG HIPRES
BUILDS DOWN INTO THE CANADIAN MARITIMES.
WHILE PW VALUES WL BE ANONYMOUSLY HIGH CORFIDI VECTORS PROGGED TO BE
ARND 10KTS DRG THE DAY. EVEN THO WINDS WL BE RELATIVELY LGT, STILL
SEEMS THAT THERE WL BE ENUF FLOW TO KEEP STORMS MVG TO PREVENT
THREAT FOR MAJOR FLASH FLOODING. CANNOT RULE OUT LOCALLY HEAVY
DOWNPOURS IN STORMS THAT ARE ABLE TO DVLP DUE TO SATD ATMOSPHERE IN
PLACE AND WL WORD AS SUCH IN HWO. CAPE VALUES WL BE TALL AND SKINNY
AND RANGE FM 500-1000 J/KG, THUS POTENTIAL ALSO EXISTS FOR SMALL
HAIL. WITH VRY LITTLE DRY AIR ALOFT EXPECTED TO WORK IN THIS AFTN,
LOOKING AT A LESSOR WIND THREAT THAN HAIL.
MAX TEMPS WL FALL A FEW DEGREES SHORT OF YDA`S VALUES AS EXTENSIVE
CLD CVR WL LIMIT SOLAR INSOLATION. HIGHS WL ONLY REACH INTO THE
U70S/ARND 80 ACRS MAJORITY OF CWA THIS AFTN.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH FRIDAY/...
415 AM UPDATE...
BACKDOOR FRONT WL ENCROACH FM THE EAST LATE TONIGHT, KEEPING THE CHC
FOR POPS AND POSSIBLY THUNDER THRU MIDNIGHT AS K-INDICES RMN IN THE
30S AND THEN QUICKLY DIMINISH AFT 04Z AS MID-LVL LAPSE RATES WEAKEN.
DRIER DWPTS AND COOLER MINS EXPECTED ACRS ERN ZONES TONIGHT AS
BACKDOOR FRONT SLIDES IN FM NEW ENGLAND THO LATEST NAM IS CERTAINLY
MORE BULLISH THAN OTHER MED RANGE GUIDANCE SO HV GONE WITH A BLEND
OF NAM, GFS AND EURO FOR T/TD/WINDS AND POPS FOR TONIGHT.
PCPN CHANCES WL WIND DOWN BY LATE AFTN WED AS SFC TROF OVR CWA WL
CONT TO PROVIDE SOURCE OF LIFT WITH DIURNAL HTG, THO POPS WL ONLY
GET AS HIGH AS 50% DRG THE DAY. SFC WINDS WL BE FM THE EAST FOR
AREAS EAST OF THE I-81 CORRIDOR, RESULTING IN COOLER HIGHS FOR WED
AFTN WHILE AREAS TWD THE FINGER LKS WL BE CLOSE TO NRML VALUES WITH
MAXES IN THE 70S.
HIPRES WL THEN BUILD IN FM NEW ENGLAND LATE WED NGT, ALLOWING SKIES
TO BEGIN TO CLR FM EAST TO WEST. COOLER TEMPS WL ACCOMPANY HIGH
PRESSURE AND ERLY FLOW WITH MRNG LOWS DIPPING INTO THE 40S OVR WRN
CATS AND 50S ELSEWHERE. ONLY A LINGERING SHOWER OR TWO IS EXPECTED
WED EVNG AS LACKLUSTER TROF PUSHES OFF TO THE EAST WITH MINIMAL FRCG
EXPECTED.
&&
.LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/...
MEDIUM RANGE MODELS ARE IN FAIR AGREEMENT THROUGH THE EXTENDED
PERIOD. FRIDAY NIGHT THROUGH SUNDAY, A FLAT UPPER LEVEL RIDGE WILL
RESIDE OVER THE AREA AS SFC HIGH PRES MOVES FROM THE VICINITY TO
ALONG THE NEW JERSEY COAST. THESE FEATURES WILL PROVIDE DRY
CONDITIONS ALONG WITH MODIFYING TEMPERATURES.
MONDAY THROUGH TUESDAY, A COLD FRONT WILL DROP SOUTH ACROSS THE
REGION AS SFC LOW PRES TRACKS ACROSS SOUTHERN CANADA. WILL CONTINUE
WITH CHC POPS THROUGH THE PERIOD FOR CONVECTION. TEMPS WILL REMAIN
CLOSE TO SEASONAL.
&&
.AVIATION /16Z TUESDAY THROUGH SATURDAY/...
12Z UPDATE...
MAINLY VFR CONDITIONS EXPECTED THROUGH TODAY BUT WITH SOME BRIEF
MVFR/IFR POSSIBLE THIS AFTERNOON IN DEVELOPING SCT -TSRA AS COLD
FRONT SINKS SOUTH ACROSS THE AREA...AT SAME TIME WEAK WAVES TRAVEL
WNW TO ESE ALOFT. BEST CHANCE FOR CONVECTION WILL BE AS FRONT SAGS
SOUTH OF KSYR-KRME DURING PEAK HEATING AND INSTABILITY...FOR
KBGM-KITH-KELM-KAVP. AS FRONT STALLS...LINGERING SHRA/TSRA WILL BE
POSSIBLE THROUGH EVENING. HAVE HANDLED INITIALLY VIA TEMPO GROUPS
FOR EXPECTED DEVELOPING SCT TSRA EARLY TO MID AFTERNOON...THEN PROB30
TSRA GROUPS INTO A PORTION OF THE EVENING FOR CENTRAL TO SOUTHERN
TERMINALS. FARTHER NORTH...KSYR-KRME LESS CONFIDENCE IN
INSTABILITY BEING REALIZED IN THE FORM OF THUNDER SO LEFT OUT OF
TAFS IN FAVOR ON NON-RESTRICTIVE SHOWERS...BUT AMENDMENTS WILL BE
MADE IF NECESSARY. TONIGHT...EXPECTING SEVERAL TERMINALS TO SLIP
INTO MVFR CIG AS SHALLOW FRONT CONTINUES TO SAG SOUTH...IFR CIG
NOT OUT OF THE QUESTION. ALSO...AREAS THAT GET RAINFALL TODAY MAY
DEVELOP FOG AND/OR LOW STRATUS LATE TONIGHT FROM LEFTOVER
MOISTURE.
OUTLOOK...
WED...RESTRICTIONS POSSIBLE FROM SCT SHRA MAINLY SOUTH OF KSYR-
KRME.
WED NGT/THU...MAINLY VFR.
THU NGT/FRI...RESTRICTIONS POSSIBLE IN SHOWERS. CHANCE TSRA FRI.
FRI NGT/SAT...MAINLY VFR.
&&
.BGM WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NY...NONE.
&&
$$
SYNOPSIS...DJP
NEAR TERM...DJP
SHORT TERM...PVN
LONG TERM...RRM
AVIATION...MDP
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
1044 AM EDT TUE MAY 27 2014
.SYNOPSIS...
A FRONTAL SYSTEM WILL DROP INTO NY STATE, AND KEEP OUR WEATHER
UNSETTLED THROUGH WEDNESDAY WITH THE CHANCE FOR SHOWERS AND
THUNDERSTORMS. HIGH PRESSURE WILL BRING FAIR WEATHER FOR THURSDAY,
BEFORE A WEAK FRONT BRINGS A FEW SHOWERS TO THE REGION EARLY
FRIDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
1041 AM UPDATE...
REORGANIZED POP GRIDS TODAY TO FOCUS LIKELY POPS MAINLY ALONG THE
NY/PA BORDER SOUTHWARD, WHERE THE INSTABILITY AND MOISTURE WILL BE
HIGHEST TODAY. TAPERED OFF TO CHANCE POPS TO THE NORTH.
CAPES IN THE 600-800 J/KG RANGE WILL COMBINE WITH A LOW FLOW WIND
FIELD, SUGGESTING LITTLE TO NO SEVERE THREAT. MORE INTERESTING IS
THE 1.50+ PWAT. GIVEN MBE VELOCITIES OF 4 TO 8 KTS, THERE IS
POTENTIAL FOR HEAVY RAIN AND EVEN SOME TRAINING. PEAK TIME FOR
CONVECTION IS BETWEEN 18Z AND 00Z.
640 AM UPDATE...
RISING DWPTS AND EXTENSIVE CLD CVR DID NOT ALLOW TEMPS TO DROP OFF
MUCH AT ALL THIS MRNG ACRS THE MOHAWK VLY/FINGER LKS WITH SYR
STILL UP ARND 70F. A FEW RENEGADE SHOWERS COURTESY OF A SUBTLE
S/WV IN NW FLOW ARE HEADING TWD ALBANY AT THIS TIME BUT HAD TO
EXPAND 20 POPS FURTHER TO THE EAST TO ACCNT FOR THESE THIS MRNG.
EXPECT A MORE PROMINENT BATCH OF SHRA/TSRA TO DVLP AFT 17Z IN
INCRSGLY MOIST FLOW AHD OF SLOW-MVG CLD FRONT.
PREV DISCO BLO...
255 AM UPDATE...
A WK S/WV IS SPARKING OFF A FEW SPRINKLES IN FINGER LKS REGION.
THESE SPRINKLES ARE FALLING OUT OF AN OVERCAST MID-DECK SO NOT
EXPECTING THEM TO AMNT TO MUCH BFR 12Z. AFT 12Z, PW VALUES WL INCRS
TO > 1.30 INCHES WHICH IS APPCHG 2 SD ABV NORMAL FOR THIS TIME OF
YR. LATEST RUC GUIDANCE APPEARS TO BE RIGHT ON TARGET WITH BLENDED
TPW PRODUCT AS OF 06Z, WITH AMNTS < 1 INCH ACRS CWA WITH PW VALUES
NEARING 1.40 INCHES IN NWPA. EXPECT HIGHER PW VALUES TO HEAD EAST
AND INTO AREA THIS AFTN WITH AMNTS BTWN 2-3 SD ABV NORMAL APPCHG
1.60 INCHES.
SFC LOPRES SITTING ALONG ONTARIO/QUEBEC BORDER WITH SFC BNDRYS
EXTNDG EAST AND WEST FM CENTER. THIS LOW DRIFTS SOUTH TDA AND ALL
MODELS BUT THE GFS AGREE ON PLACEMENT OF LOW CNTR OVR SERN ONTARIO
AS OF 18Z THIS AFTN. MAIN CDFNT WL BE LOCATED ACRS SRN PORTIONS OF
ONTARIO BACK INTO LWR MICHIGAN WHILE A BACKDOOR-TYPE COLD FRONT WL
BE PUSHING IN FM NEW ENGLAND LATE AFTN/EVNG HRS AS STRONG HIPRES
BUILDS DOWN INTO THE CANADIAN MARITIMES.
WHILE PW VALUES WL BE ANONYMOUSLY HIGH CORFIDI VECTORS PROGGED TO BE
ARND 10KTS DRG THE DAY. EVEN THO WINDS WL BE RELATIVELY LGT, STILL
SEEMS THAT THERE WL BE ENUF FLOW TO KEEP STORMS MVG TO PREVENT
THREAT FOR MAJOR FLASH FLOODING. CANNOT RULE OUT LOCALLY HEAVY
DOWNPOURS IN STORMS THAT ARE ABLE TO DVLP DUE TO SATD ATMOSPHERE IN
PLACE AND WL WORD AS SUCH IN HWO. CAPE VALUES WL BE TALL AND SKINNY
AND RANGE FM 500-1000 J/KG, THUS POTENTIAL ALSO EXISTS FOR SMALL
HAIL. WITH VRY LITTLE DRY AIR ALOFT EXPECTED TO WORK IN THIS AFTN,
LOOKING AT A LESSOR WIND THREAT THAN HAIL.
MAX TEMPS WL FALL A FEW DEGREES SHORT OF YDA`S VALUES AS EXTENSIVE
CLD CVR WL LIMIT SOLAR INSOLATION. HIGHS WL ONLY REACH INTO THE
U70S/ARND 80 ACRS MAJORITY OF CWA THIS AFTN.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH WEDNESDAY NIGHT/...
415 AM UPDATE...
BACKDOOR FRONT WL ENCROACH FM THE EAST LATE TONIGHT, KEEPING THE CHC
FOR POPS AND POSSIBLY THUNDER THRU MIDNIGHT AS K-INDICES RMN IN THE
30S AND THEN QUICKLY DIMINISH AFT 04Z AS MID-LVL LAPSE RATES WEAKEN.
DRIER DWPTS AND COOLER MINS EXPECTED ACRS ERN ZONES TONIGHT AS
BACKDOOR FRONT SLIDES IN FM NEW ENGLAND THO LATEST NAM IS CERTAINLY
MORE BULLISH THAN OTHER MED RANGE GUIDANCE SO HV GONE WITH A BLEND
OF NAM, GFS AND EURO FOR T/TD/WINDS AND POPS FOR TONIGHT.
PCPN CHANCES WL WIND DOWN BY LATE AFTN WED AS SFC TROF OVR CWA WL
CONT TO PROVIDE SOURCE OF LIFT WITH DIURNAL HTG, THO POPS WL ONLY
GET AS HIGH AS 50% DRG THE DAY. SFC WINDS WL BE FM THE EAST FOR
AREAS EAST OF THE I-81 CORRIDOR, RESULTING IN COOLER HIGHS FOR WED
AFTN WHILE AREAS TWD THE FINGER LKS WL BE CLOSE TO NRML VALUES WITH
MAXES IN THE 70S.
HIPRES WL THEN BUILD IN FM NEW ENGLAND LATE WED NGT, ALLOWING SKIES
TO BEGIN TO CLR FM EAST TO WEST. COOLER TEMPS WL ACCOMPANY HIGH
PRESSURE AND ERLY FLOW WITH MRNG LOWS DIPPING INTO THE 40S OVR WRN
CATS AND 50S ELSEWHERE. ONLY A LINGERING SHOWER OR TWO IS EXPECTED
WED EVNG AS LACKLUSTER TROF PUSHES OFF TO THE EAST WITH MINIMAL FRCG
EXPECTED.
&&
.LONG TERM /THURSDAY THROUGH MONDAY/...
415 AM UPDATE...
FAIRLY QUIET PERIOD OF WEATHER...ONLY INTERRUPTED BY A WEAK
FRONTAL PASSAGE THURSDAY NIGHT INTO FRIDAY...AND THEN APPROACH OF
A FRONTAL SYSTEM EARLY NEXT WEEK.
ON THURSDAY...OUR WEATHER WILL BE DOMINATED BY BROAD HIGH PRESSURE
CENTERED OVER COASTAL NEW ENGLAND. MODELS INDICATE THAT MOISTURE
TRAPPED UNDER SUBSIDENCE INVERSION MAY BE RELUCTANT TO MIX
OUT...ESPECIALLY CONSIDERING STABLE MARINE LAYER INFLUENCE FROM
SOUTHEAST FLOW AROUND THE HIGH. STILL EXPECTING DRY WEATHER...BUT
SHALLOW LAYER OF CLOUDS AND MARINE LAYER PROMPTED ME TO SCALE BACK
HIGH TEMPERATURES A BIT MORE...INTO MAINLY MID TO UPPER 60S
EXCEPT FOR LOW 70S IN THE LAKE PLAIN. POCONOS/WESTERN CATSKILLS
MAY EVEN BE STUCK IN THE LOW 60S FOR HIGHS.
DIVIDING THE COASTAL HIGH...FROM ANOTHER HIGH PRESSURE CENTER OVER
HUDSON BAY...WILL BE A WEAK FRONT THAT WILL DROP THROUGH SOMETIME
AROUND FRIDAY MORNING. I HAVE CENTERED LOW TO MID CHANCE RANGE
POPS AROUND LATE THURSDAY NIGHT-FRIDAY MORNING TIME FRAME.
DIURNALLY UNFAVORABLE TIMING OF FRONTAL PASSAGE...AND MARGINAL AT
BEST INSTABILITY ALONG WITH LIMITED MOISTURE...COMPELLED ME TO
ONLY INCLUDE SLIGHT CHANCE OF THUNDER AT THIS TIME.
HUDSON BAY HIGH PRESSURE WILL THEN BUILD OVER THE NORTHEAST STATES
OVER THE WEEKEND...YIELDING DRY WEATHER...FAIR SKIES...AND AT LEAST
NEAR NORMAL TEMPERATURES THAT SHOULD TREND SLIGHTLY WARMER WITH
TIME. I WAS ABLE TO DELAY NEXT MENTIONABLE CHANCE OF RAIN UNTIL AT
LEAST MONDAY...BUT MODELS DISAGREE ON WHEN THIS ENTERS THE
PICTURE. ECMWF IS FASTER TO FLATTEN UPPER RIDGE AND ALLOWS FRONTAL
SYSTEM IN AS EARLY AS MONDAY...GFS MEANWHILE MAINTAINS RIDGING YET
ALSO ALLOWS SLIGHTLY MORE UNSTABLE AIRMASS INTO REGION WITH TIME
WITH MORE OF A WARM FRONTAL REGIME.
&&
.AVIATION /15Z TUESDAY THROUGH SATURDAY/...
12Z UPDATE...
MAINLY VFR CONDITIONS EXPECTED THROUGH TODAY BUT WITH SOME BRIEF
MVFR/IFR POSSIBLE THIS AFTERNOON IN DEVELOPING SCT -TSRA AS COLD
FRONT SINKS SOUTH ACROSS THE AREA...AT SAME TIME WEAK WAVES TRAVEL
WNW TO ESE ALOFT. BEST CHANCE FOR CONVECTION WILL BE AS FRONT SAGS
SOUTH OF KSYR-KRME DURING PEAK HEATING AND INSTABILITY...FOR
KBGM-KITH-KELM-KAVP. AS FRONT STALLS...LINGERING SHRA/TSRA WILL BE
POSSIBLE THROUGH EVENING. HAVE HANDLED INITIALLY VIA TEMPO GROUPS
FOR EXPECTED DEVELOPING SCT TSRA EARLY TO MID AFTERNOON...THEN PROB30
TSRA GROUPS INTO A PORTION OF THE EVENING FOR CENTRAL TO SOUTHERN
TERMINALS. FARTHER NORTH...KSYR-KRME LESS CONFIDENCE IN
INSTABILITY BEING REALIZED IN THE FORM OF THUNDER SO LEFT OUT OF
TAFS IN FAVOR ON NON-RESTRICTIVE SHOWERS...BUT AMENDMENTS WILL BE
MADE IF NECESSARY. TONIGHT...EXPECTING SEVERAL TERMINALS TO SLIP
INTO MVFR CIG AS SHALLOW FRONT CONTINUES TO SAG SOUTH...IFR CIG
NOT OUT OF THE QUESTION. ALSO...AREAS THAT GET RAINFALL TODAY MAY
DEVELOP FOG AND/OR LOW STRATUS LATE TONIGHT FROM LEFTOVER
MOISTURE.
OUTLOOK...
WED...RESTRICTIONS POSSIBLE FROM SCT SHRA MAINLY SOUTH OF KSYR-
KRME.
WED NGT/THU...MAINLY VFR.
THU NGT/FRI...RESTRICTIONS POSSIBLE IN SHOWERS. CHANCE TSRA FRI.
FRI NGT/SAT...MAINLY VFR.
&&
.BGM WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NY...NONE.
&&
$$
SYNOPSIS...DJP
NEAR TERM...DJP
SHORT TERM...PVN
LONG TERM...MDP
AVIATION...MDP
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
704 AM EDT TUE MAY 27 2014
.SYNOPSIS...
A STORM SYSTEM WILL MOVE INTO THE REGION TODAY BRINGING A CHANCE
FOR SHOWERS AND THUNDERSTORMS THROUGH WEDNESDAY AFTERNOON. MAINLY
DRY WEATHER IS FIGURED LATER THIS WEEK THROUGH NEXT WEEKEND...EXCEPT
FOR A CHANCE OF SHOWERS AND THUNDERSTORMS THURSDAY NIGHT INTO
FRIDAY AS A WEAK FRONT MOVES THROUGH THE REGION.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
640 AM UPDATE...
RISING DWPTS AND EXTENSIVE CLD CVR DID NOT ALLOW TEMPS TO DROP OFF
MUCH AT ALL THIS MRNG ACRS THE MOHAWK VLY/FINGER LKS WITH SYR
STILL UP ARND 70F. A FEW RENEGADE SHOWERS COURTESY OF A SUBTLE
S/WV IN NW FLOW ARE HEADING TWD ALBANY AT THIS TIME BUT HAD TO
EXPAND 20 POPS FURTHER TO THE EAST TO ACCNT FOR THESE THIS MRNG.
EXPECT A MORE PROMINENT BATCH OF SHRA/TSRA TO DVLP AFT 17Z IN
INCRSGLY MOIST FLOW AHD OF SLOW-MVG CLD FRONT.
PREV DISCO BLO...
255 AM UPDATE...
A WK S/WV IS SPARKING OFF A FEW SPRINKLES IN FINGER LKS REGION.
THESE SPRINKLES ARE FALLING OUT OF AN OVERCAST MID-DECK SO NOT
EXPECTING THEM TO AMNT TO MUCH BFR 12Z. AFT 12Z, PW VALUES WL INCRS
TO > 1.30 INCHES WHICH IS APPCHG 2 SD ABV NORMAL FOR THIS TIME OF
YR. LATEST RUC GUIDANCE APPEARS TO BE RIGHT ON TARGET WITH BLENDED
TPW PRODUCT AS OF 06Z, WITH AMNTS < 1 INCH ACRS CWA WITH PW VALUES
NEARING 1.40 INCHES IN NWPA. EXPECT HIGHER PW VALUES TO HEAD EAST
AND INTO AREA THIS AFTN WITH AMNTS BTWN 2-3 SD ABV NORMAL APPCHG
1.60 INCHES.
SFC LOPRES SITTING ALONG ONTARIO/QUEBEC BORDER WITH SFC BNDRYS
EXTNDG EAST AND WEST FM CENTER. THIS LOW DRIFTS SOUTH TDA AND ALL
MODELS BUT THE GFS AGREE ON PLACEMENT OF LOW CNTR OVR SERN ONTARIO
AS OF 18Z THIS AFTN. MAIN CDFNT WL BE LOCATED ACRS SRN PORTIONS OF
ONTARIO BACK INTO LWR MICHIGAN WHILE A BACKDOOR-TYPE COLD FRONT WL
BE PUSHING IN FM NEW ENGLAND LATE AFTN/EVNG HRS AS STRONG HIPRES
BUILDS DOWN INTO THE CANADIAN MARITIMES.
WHILE PW VALUES WL BE ANONYMOUSLY HIGH CORFIDI VECTORS PROGGED TO BE
ARND 10KTS DRG THE DAY. EVEN THO WINDS WL BE RELATIVELY LGT, STILL
SEEMS THAT THERE WL BE ENUF FLOW TO KEEP STORMS MVG TO PREVENT
THREAT FOR MAJOR FLASH FLOODING. CANNOT RULE OUT LOCALLY HEAVY
DOWNPOURS IN STORMS THAT ARE ABLE TO DVLP DUE TO SATD ATMOSPHERE IN
PLACE AND WL WORD AS SUCH IN HWO. CAPE VALUES WL BE TALL AND SKINNY
AND RANGE FM 500-1000 J/KG, THUS POTENTIAL ALSO EXISTS FOR SMALL
HAIL. WITH VRY LITTLE DRY AIR ALOFT EXPECTED TO WORK IN THIS AFTN,
LOOKING AT A LESSOR WIND THREAT THAN HAIL.
MAX TEMPS WL FALL A FEW DEGREES SHORT OF YDA`S VALUES AS EXTENSIVE
CLD CVR WL LIMIT SOLAR INSOLATION. HIGHS WL ONLY REACH INTO THE
U70S/ARND 80 ACRS MAJORITY OF CWA THIS AFTN.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH WEDNESDAY NIGHT/...
415 AM UPDATE...
BACKDOOR FRONT WL ENCROACH FM THE EAST LATE TONIGHT, KEEPING THE CHC
FOR POPS AND POSSIBLY THUNDER THRU MIDNIGHT AS K-INDICES RMN IN THE
30S AND THEN QUICKLY DIMINISH AFT 04Z AS MID-LVL LAPSE RATES WEAKEN.
DRIER DWPTS AND COOLER MINS EXPECTED ACRS ERN ZONES TONIGHT AS
BACKDOOR FRONT SLIDES IN FM NEW ENGLAND THO LATEST NAM IS CERTAINLY
MORE BULLISH THAN OTHER MED RANGE GUIDANCE SO HV GONE WITH A BLEND
OF NAM, GFS AND EURO FOR T/TD/WINDS AND POPS FOR TONIGHT.
PCPN CHANCES WL WIND DOWN BY LATE AFTN WED AS SFC TROF OVR CWA WL
CONT TO PROVIDE SOURCE OF LIFT WITH DIURNAL HTG, THO POPS WL ONLY
GET AS HIGH AS 50% DRG THE DAY. SFC WINDS WL BE FM THE EAST FOR
AREAS EAST OF THE I-81 CORRIDOR, RESULTING IN COOLER HIGHS FOR WED
AFTN WHILE AREAS TWD THE FINGER LKS WL BE CLOSE TO NRML VALUES WITH
MAXES IN THE 70S.
HIPRES WL THEN BUILD IN FM NEW ENGLAND LATE WED NGT, ALLOWING SKIES
TO BEGIN TO CLR FM EAST TO WEST. COOLER TEMPS WL ACCOMPANY HIGH
PRESSURE AND ERLY FLOW WITH MRNG LOWS DIPPING INTO THE 40S OVR WRN
CATS AND 50S ELSEWHERE. ONLY A LINGERING SHOWER OR TWO IS EXPECTED
WED EVNG AS LACKLUSTER TROF PUSHES OFF TO THE EAST WITH MINIMAL FRCG
EXPECTED.
&&
.LONG TERM /THURSDAY THROUGH MONDAY/...
415 AM UPDATE...
FAIRLY QUIET PERIOD OF WEATHER...ONLY INTERRUPTED BY A WEAK
FRONTAL PASSAGE THURSDAY NIGHT INTO FRIDAY...AND THEN APPROACH OF
A FRONTAL SYSTEM EARLY NEXT WEEK.
ON THURSDAY...OUR WEATHER WILL BE DOMINATED BY BROAD HIGH PRESSURE
CENTERED OVER COASTAL NEW ENGLAND. MODELS INDICATE THAT MOISTURE
TRAPPED UNDER SUBSIDENCE INVERSION MAY BE RELUCTANT TO MIX
OUT...ESPECIALLY CONSIDERING STABLE MARINE LAYER INFLUENCE FROM
SOUTHEAST FLOW AROUND THE HIGH. STILL EXPECTING DRY WEATHER...BUT
SHALLOW LAYER OF CLOUDS AND MARINE LAYER PROMPTED ME TO SCALE BACK
HIGH TEMPERATURES A BIT MORE...INTO MAINLY MID TO UPPER 60S
EXCEPT FOR LOW 70S IN THE LAKE PLAIN. POCONOS/WESTERN CATSKILLS
MAY EVEN BE STUCK IN THE LOW 60S FOR HIGHS.
DIVIDING THE COASTAL HIGH...FROM ANOTHER HIGH PRESSURE CENTER OVER
HUDSON BAY...WILL BE A WEAK FRONT THAT WILL DROP THROUGH SOMETIME
AROUND FRIDAY MORNING. I HAVE CENTERED LOW TO MID CHANCE RANGE
POPS AROUND LATE THURSDAY NIGHT-FRIDAY MORNING TIME FRAME.
DIURNALLY UNFAVORABLE TIMING OF FRONTAL PASSAGE...AND MARGINAL AT
BEST INSTABILITY ALONG WITH LIMITED MOISTURE...COMPELLED ME TO
ONLY INCLUDE SLIGHT CHANCE OF THUNDER AT THIS TIME.
HUDSON BAY HIGH PRESSURE WILL THEN BUILD OVER THE NORTHEAST STATES
OVER THE WEEKEND...YIELDING DRY WEATHER...FAIR SKIES...AND AT LEAST
NEAR NORMAL TEMPERATURES THAT SHOULD TREND SLIGHTLY WARMER WITH
TIME. I WAS ABLE TO DELAY NEXT MENTIONABLE CHANCE OF RAIN UNTIL AT
LEAST MONDAY...BUT MODELS DISAGREE ON WHEN THIS ENTERS THE
PICTURE. ECMWF IS FASTER TO FLATTEN UPPER RIDGE AND ALLOWS FRONTAL
SYSTEM IN AS EARLY AS MONDAY...GFS MEANWHILE MAINTAINS RIDGING YET
ALSO ALLOWS SLIGHTLY MORE UNSTABLE AIRMASS INTO REGION WITH TIME
WITH MORE OF A WARM FRONTAL REGIME.
&&
.AVIATION /11Z TUESDAY THROUGH SATURDAY/...
12Z UPDATE...
MAINLY VFR CONDITIONS EXPECTED THROUGH TODAY BUT WITH SOME BRIEF
MVFR/IFR POSSIBLE THIS AFTERNOON IN DEVELOPING SCT -TSRA AS COLD
FRONT SINKS SOUTH ACROSS THE AREA...AT SAME TIME WEAK WAVES TRAVEL
WNW TO ESE ALOFT. BEST CHANCE FOR CONVECTION WILL BE AS FRONT SAGS
SOUTH OF KSYR-KRME DURING PEAK HEATING AND INSTABILITY...FOR
KBGM-KITH-KELM-KAVP. AS FRONT STALLS...LINGERING SHRA/TSRA WILL BE
POSSIBLE THROUGH EVENING. HAVE HANDLED INITIALLY VIA TEMPO GROUPS
FOR EXPECTED DEVELOPING SCT TSRA EARLY TO MID AFTERNOON...THEN PROB30
TSRA GROUPS INTO A PORTION OF THE EVENING FOR CENTRAL TO SOUTHERN
TERMINALS. FARTHER NORTH...KSYR-KRME LESS CONFIDENCE IN
INSTABILITY BEING REALIZED IN THE FORM OF THUNDER SO LEFT OUT OF
TAFS IN FAVOR ON NON-RESTRICTIVE SHOWERS...BUT AMENDMENTS WILL BE
MADE IF NECESSARY. TONIGHT...EXPECTING SEVERAL TERMINALS TO SLIP
INTO MVFR CIG AS SHALLOW FRONT CONTINUES TO SAG SOUTH...IFR CIG
NOT OUT OF THE QUESTION. ALSO...AREAS THAT GET RAINFALL TODAY MAY
DEVELOP FOG AND/OR LOW STRATUS LATE TONIGHT FROM LEFTOVER
MOISTURE.
OUTLOOK...
WED...RESTRICTIONS POSSIBLE FROM SCT SHRA MAINLY SOUTH OF KSYR-
KRME.
WED NGT/THU...MAINLY VFR.
THU NGT/FRI...RESTRICTIONS POSSIBLE IN SHOWERS. CHANCE TSRA FRI.
FRI NGT/SAT...MAINLY VFR.
&&
.BGM WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NY...NONE.
&&
$$
SYNOPSIS...MDP/PVN
NEAR TERM...PVN
SHORT TERM...PVN
LONG TERM...MDP
AVIATION...MDP
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
640 AM EDT TUE MAY 27 2014
.SYNOPSIS...
A STORM SYSTEM WILL MOVE INTO THE REGION TODAY BRINGING A CHANCE
FOR SHOWERS AND THUNDERSTORMS THROUGH WEDNESDAY AFTERNOON. MAINLY
DRY WEATHER IS FIGURED LATER THIS WEEK THROUGH NEXT WEEKEND...EXCEPT
FOR A CHANCE OF SHOWERS AND THUNDERSTORMS THURSDAY NIGHT INTO
FRIDAY AS A WEAK FRONT MOVES THROUGH THE REGION.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
640 AM UPDATE...
RISING DWPTS AND EXTENSIVE CLD CVR DID NOT ALLOW TEMPS TO DROP OFF
MUCH AT ALL THIS MRNG ACRS THE MOHAWK VLY/FINGER LKS WITH SYR
STILL UP ARND 70F. A FEW RENEGADE SHOWERS COURTESY OF A SUBTLE
S/WV IN NW FLOW ARE HEADING TWD ALBANY AT THIS TIME BUT HAD TO
EXPAND 20 POPS FURTHER TO THE EAST TO ACCNT FOR THESE THIS MRNG.
EXPECT A MORE PROMINENT BATCH OF SHRA/TSRA TO DVLP AFT 17Z IN
INCRSGLY MOIST FLOW AHD OF SLOW-MVG CLD FRONT.
PREV DISCO BLO...
255 AM UPDATE...
A WK S/WV IS SPARKING OFF A FEW SPRINKLES IN FINGER LKS REGION.
THESE SPRINKLES ARE FALLING OUT OF AN OVERCAST MID-DECK SO NOT
EXPECTING THEM TO AMNT TO MUCH BFR 12Z. AFT 12Z, PW VALUES WL INCRS
TO > 1.30 INCHES WHICH IS APPCHG 2 SD ABV NORMAL FOR THIS TIME OF
YR. LATEST RUC GUIDANCE APPEARS TO BE RIGHT ON TARGET WITH BLENDED
TPW PRODUCT AS OF 06Z, WITH AMNTS < 1 INCH ACRS CWA WITH PW VALUES
NEARING 1.40 INCHES IN NWPA. EXPECT HIGHER PW VALUES TO HEAD EAST
AND INTO AREA THIS AFTN WITH AMNTS BTWN 2-3 SD ABV NORMAL APPCHG
1.60 INCHES.
SFC LOPRES SITTING ALONG ONTARIO/QUEBEC BORDER WITH SFC BNDRYS
EXTNDG EAST AND WEST FM CENTER. THIS LOW DRIFTS SOUTH TDA AND ALL
MODELS BUT THE GFS AGREE ON PLACEMENT OF LOW CNTR OVR SERN ONTARIO
AS OF 18Z THIS AFTN. MAIN CDFNT WL BE LOCATED ACRS SRN PORTIONS OF
ONTARIO BACK INTO LWR MICHIGAN WHILE A BACKDOOR-TYPE COLD FRONT WL
BE PUSHING IN FM NEW ENGLAND LATE AFTN/EVNG HRS AS STRONG HIPRES
BUILDS DOWN INTO THE CANADIAN MARITIMES.
WHILE PW VALUES WL BE ANONYMOUSLY HIGH CORFIDI VECTORS PROGGED TO BE
ARND 10KTS DRG THE DAY. EVEN THO WINDS WL BE RELATIVELY LGT, STILL
SEEMS THAT THERE WL BE ENUF FLOW TO KEEP STORMS MVG TO PREVENT
THREAT FOR MAJOR FLASH FLOODING. CANNOT RULE OUT LOCALLY HEAVY
DOWNPOURS IN STORMS THAT ARE ABLE TO DVLP DUE TO SATD ATMOSPHERE IN
PLACE AND WL WORD AS SUCH IN HWO. CAPE VALUES WL BE TALL AND SKINNY
AND RANGE FM 500-1000 J/KG, THUS POTENTIAL ALSO EXISTS FOR SMALL
HAIL. WITH VRY LITTLE DRY AIR ALOFT EXPECTED TO WORK IN THIS AFTN,
LOOKING AT A LESSOR WIND THREAT THAN HAIL.
MAX TEMPS WL FALL A FEW DEGREES SHORT OF YDA`S VALUES AS EXTENSIVE
CLD CVR WL LIMIT SOLAR INSOLATION. HIGHS WL ONLY REACH INTO THE
U70S/ARND 80 ACRS MAJORITY OF CWA THIS AFTN.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH WEDNESDAY NIGHT/...
415 AM UPDATE...
BACKDOOR FRONT WL ENCROACH FM THE EAST LATE TONIGHT, KEEPING THE CHC
FOR POPS AND POSSIBLY THUNDER THRU MIDNIGHT AS K-INDICES RMN IN THE
30S AND THEN QUICKLY DIMINISH AFT 04Z AS MID-LVL LAPSE RATES WEAKEN.
DRIER DWPTS AND COOLER MINS EXPECTED ACRS ERN ZONES TONIGHT AS
BACKDOOR FRONT SLIDES IN FM NEW ENGLAND THO LATEST NAM IS CERTAINLY
MORE BULLISH THAN OTHER MED RANGE GUIDANCE SO HV GONE WITH A BLEND
OF NAM, GFS AND EURO FOR T/TD/WINDS AND POPS FOR TONIGHT.
PCPN CHANCES WL WIND DOWN BY LATE AFTN WED AS SFC TROF OVR CWA WL
CONT TO PROVIDE SOURCE OF LIFT WITH DIURNAL HTG, THO POPS WL ONLY
GET AS HIGH AS 50% DRG THE DAY. SFC WINDS WL BE FM THE EAST FOR
AREAS EAST OF THE I-81 CORRIDOR, RESULTING IN COOLER HIGHS FOR WED
AFTN WHILE AREAS TWD THE FINGER LKS WL BE CLOSE TO NRML VALUES WITH
MAXES IN THE 70S.
HIPRES WL THEN BUILD IN FM NEW ENGLAND LATE WED NGT, ALLOWING SKIES
TO BEGIN TO CLR FM EAST TO WEST. COOLER TEMPS WL ACCOMPANY HIGH
PRESSURE AND ERLY FLOW WITH MRNG LOWS DIPPING INTO THE 40S OVR WRN
CATS AND 50S ELSEWHERE. ONLY A LINGERING SHOWER OR TWO IS EXPECTED
WED EVNG AS LACKLUSTER TROF PUSHES OFF TO THE EAST WITH MINIMAL FRCG
EXPECTED.
&&
.LONG TERM /THURSDAY THROUGH MONDAY/...
415 AM UPDATE...
FAIRLY QUIET PERIOD OF WEATHER...ONLY INTERRUPTED BY A WEAK
FRONTAL PASSAGE THURSDAY NIGHT INTO FRIDAY...AND THEN APPROACH OF
A FRONTAL SYSTEM EARLY NEXT WEEK.
ON THURSDAY...OUR WEATHER WILL BE DOMINATED BY BROAD HIGH PRESSURE
CENTERED OVER COASTAL NEW ENGLAND. MODELS INDICATE THAT MOISTURE
TRAPPED UNDER SUBSIDENCE INVERSION MAY BE RELUCTANT TO MIX
OUT...ESPECIALLY CONSIDERING STABLE MARINE LAYER INFLUENCE FROM
SOUTHEAST FLOW AROUND THE HIGH. STILL EXPECTING DRY WEATHER...BUT
SHALLOW LAYER OF CLOUDS AND MARINE LAYER PROMPTED ME TO SCALE BACK
HIGH TEMPERATURES A BIT MORE...INTO MAINLY MID TO UPPER 60S
EXCEPT FOR LOW 70S IN THE LAKE PLAIN. POCONOS/WESTERN CATSKILLS
MAY EVEN BE STUCK IN THE LOW 60S FOR HIGHS.
DIVIDING THE COASTAL HIGH...FROM ANOTHER HIGH PRESSURE CENTER OVER
HUDSON BAY...WILL BE A WEAK FRONT THAT WILL DROP THROUGH SOMETIME
AROUND FRIDAY MORNING. I HAVE CENTERED LOW TO MID CHANCE RANGE
POPS AROUND LATE THURSDAY NIGHT-FRIDAY MORNING TIME FRAME.
DIURNALLY UNFAVORABLE TIMING OF FRONTAL PASSAGE...AND MARGINAL AT
BEST INSTABILITY ALONG WITH LIMITED MOISTURE...COMPELLED ME TO
ONLY INCLUDE SLIGHT CHANCE OF THUNDER AT THIS TIME.
HUDSON BAY HIGH PRESSURE WILL THEN BUILD OVER THE NORTHEAST STATES
OVER THE WEEKEND...YIELDING DRY WEATHER...FAIR SKIES...AND AT LEAST
NEAR NORMAL TEMPERATURES THAT SHOULD TREND SLIGHTLY WARMER WITH
TIME. I WAS ABLE TO DELAY NEXT MENTIONABLE CHANCE OF RAIN UNTIL AT
LEAST MONDAY...BUT MODELS DISAGREE ON WHEN THIS ENTERS THE
PICTURE. ECMWF IS FASTER TO FLATTEN UPPER RIDGE AND ALLOWS FRONTAL
SYSTEM IN AS EARLY AS MONDAY...GFS MEANWHILE MAINTAINS RIDGING YET
ALSO ALLOWS SLIGHTLY MORE UNSTABLE AIRMASS INTO REGION WITH TIME
WITH MORE OF A WARM FRONTAL REGIME.
&&
.AVIATION /12Z TUESDAY THROUGH SATURDAY/...
06Z UPDATE...
MAINLY VFR CONDITIONS EXPECTED BUT WITH SOME BRIEF MVFR/IFR POSSIBLE
THIS AFTERNOON IN DEVELOPING SCT -TSRA AS COLD FRONT SINKS SOUTH
ACROSS THE AREA...AT SAME TIME WEAK WAVES TRAVEL WNW TO ESE ALOFT.
BEST CHANCE FOR CONVECTION WILL BE AS FRONT SAGS SOUTH OF KSYR-
KRME DURING PEAK HEATING AND INSTABILITY...FOR KBGM-KITH-KELM-KAVP.
AS FRONT STALLS...LINGERING SHRA/TSRA WILL BE POSSIBLE THROUGH
EVENING. HAVE HANDLED INITIALLY VIA TEMPO GROUPS FOR EXPECTED
DEVELOPING SCT TSRA THIS AFTERNOON...THEN PROB30 TSRA GROUPS INTO
A PORTION OF THE EVENING FOR CENTRAL TO SOUTHERN TERMINALS.
FARTHER NORTH...KSYR-KRME PROB30 GROUPS THIS AFTERNOON...WHERE
THERE IS LESS CONFIDENCE IN INSTABILITY BEING REALIZED IN THE FORM
OF THUNDER. TUESDAY NIGHT...EXPECTING SEVERAL TERMINALS TO SLIP
INTO MVFR CIG AS SHALLOW FRONT CONTINUES TO SAG SOUTH AND/OR SCT
SHRA-TSRA CONTINUES ALONG IT.
OUTLOOK...
LATE TUE NGT/WED...RESTRICTIONS POSSIBLE FROM SCT SHRA/TSRA MAINLY
SOUTH OF KSYR-KRME.
WED NGT/THU...MAINLY VFR.
THU NGT/FRI...RESTRICTIONS POSSIBLE IN SHOWERS. CHANCE TSRA FRI.
FRI NGT/SAT...MAINLY VFR.
&&
.BGM WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NY...NONE.
&&
$$
SYNOPSIS...MDP/PVN
NEAR TERM...PVN
SHORT TERM...PVN
LONG TERM...MDP
AVIATION...MDP
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
418 AM EDT TUE MAY 27 2014
.SYNOPSIS...
A STORM SYSTEM WILL MOVE INTO THE REGION TODAY BRINGING A CHANCE
FOR SHOWERS AND THUNDERSTORMS THROUGH WEDNESDAY AFTERNOON. MAINLY
DRY WEATHER IS FIGURED LATER THIS WEEK THROUGH NEXT WEEKEND...EXCEPT
FOR A CHANCE OF SHOWERS AND THUNDERSTORMS THURSDAY NIGHT INTO
FRIDAY AS A WEAK FRONT MOVES THROUGH THE REGION.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
255 AM UPDATE...
A WK S/WV IS SPARKING OFF A FEW SPRINKLES IN FINGER LKS REGION.
THESE SPRINKLES ARE FALLING OUT OF AN OVERCAST MID-DECK SO NOT
EXPECTING THEM TO AMNT TO MUCH BFR 12Z. AFT 12Z, PW VALUES WL INCRS
TO > 1.30 INCHES WHICH IS APPCHG 2 SD ABV NORMAL FOR THIS TIME OF
YR. LATEST RUC GUIDANCE APPEARS TO BE RIGHT ON TARGET WITH BLENDED
TPW PRODUCT AS OF 06Z, WITH AMNTS < 1 INCH ACRS CWA WITH PW VALUES
NEARING 1.40 INCHES IN NWPA. EXPECT HIGHER PW VALUES TO HEAD EAST
AND INTO AREA THIS AFTN WITH AMNTS BTWN 2-3 SD ABV NORMAL APPCHG
1.60 INCHES.
SFC LOPRES SITTING ALONG ONTARIO/QUEBEC BORDER WITH SFC BNDRYS
EXTNDG EAST AND WEST FM CENTER. THIS LOW DRIFTS SOUTH TDA AND ALL
MODELS BUT THE GFS AGREE ON PLACEMENT OF LOW CNTR OVR SERN ONTARIO
AS OF 18Z THIS AFTN. MAIN CDFNT WL BE LOCATED ACRS SRN PORTIONS OF
ONTARIO BACK INTO LWR MICHIGAN WHILE A BACKDOOR-TYPE COLD FRONT WL
BE PUSHING IN FM NEW ENGLAND LATE AFTN/EVNG HRS AS STRONG HIPRES
BUILDS DOWN INTO THE CANADIAN MARITIMES.
WHILE PW VALUES WL BE ANONYMOUSLY HIGH CORFIDI VECTORS PROGGED TO BE
ARND 10KTS DRG THE DAY. EVEN THO WINDS WL BE RELATIVELY LGT, STILL
SEEMS THAT THERE WL BE ENUF FLOW TO KEEP STORMS MVG TO PREVENT
THREAT FOR MAJOR FLASH FLOODING. CANNOT RULE OUT LOCALLY HEAVY
DOWNPOURS IN STORMS THAT ARE ABLE TO DVLP DUE TO SATD ATMOSPHERE IN
PLACE AND WL WORD AS SUCH IN HWO. CAPE VALUES WL BE TALL AND SKINNY
AND RANGE FM 500-1000 J/KG, THUS POTENTIAL ALSO EXISTS FOR SMALL
HAIL. WITH VRY LITTLE DRY AIR ALOFT EXPECTED TO WORK IN THIS AFTN,
LOOKING AT A LESSOR WIND THREAT THAN HAIL.
MAX TEMPS WL FALL A FEW DEGREES SHORT OF YDA`S VALUES AS EXTENSIVE
CLD CVR WL LIMIT SOLAR INSOLATION. HIGHS WL ONLY REACH INTO THE
U70S/ARND 80 ACRS MAJORITY OF CWA THIS AFTN.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH WEDNESDAY NIGHT/...
415 AM UPDATE...
BACKDOOR FRONT WL ENCROACH FM THE EAST LATE TONIGHT, KEEPING THE CHC
FOR POPS AND POSSIBLY THUNDER THRU MIDNIGHT AS K-INDICES RMN IN THE
30S AND THEN QUICKLY DIMINISH AFT 04Z AS MID-LVL LAPSE RATES WEAKEN.
DRIER DWPTS AND COOLER MINS EXPECTED ACRS ERN ZONES TONIGHT AS
BACKDOOR FRONT SLIDES IN FM NEW ENGLAND THO LATEST NAM IS CERTAINLY
MORE BULLISH THAN OTHER MED RANGE GUIDANCE SO HV GONE WITH A BLEND
OF NAM, GFS AND EURO FOR T/TD/WINDS AND POPS FOR TONIGHT.
PCPN CHANCES WL WIND DOWN BY LATE AFTN WED AS SFC TROF OVR CWA WL
CONT TO PROVIDE SOURCE OF LIFT WITH DIURNAL HTG, THO POPS WL ONLY
GET AS HIGH AS 50% DRG THE DAY. SFC WINDS WL BE FM THE EAST FOR
AREAS EAST OF THE I-81 CORRIDOR, RESULTING IN COOLER HIGHS FOR WED
AFTN WHILE AREAS TWD THE FINGER LKS WL BE CLOSE TO NRML VALUES WITH
MAXES IN THE 70S.
HIPRES WL THEN BUILD IN FM NEW ENGLAND LATE WED NGT, ALLOWING SKIES
TO BEGIN TO CLR FM EAST TO WEST. COOLER TEMPS WL ACCOMPANY HIGH
PRESSURE AND ERLY FLOW WITH MRNG LOWS DIPPING INTO THE 40S OVR WRN
CATS AND 50S ELSEWHERE. ONLY A LINGERING SHOWER OR TWO IS EXPECTED
WED EVNG AS LACKLUSTER TROF PUSHES OFF TO THE EAST WITH MINIMAL FRCG
EXPECTED.
&&
.LONG TERM /THURSDAY THROUGH MONDAY/...
415 AM UPDATE...
FAIRLY QUIET PERIOD OF WEATHER...ONLY INTERRUPTED BY A WEAK
FRONTAL PASSAGE THURSDAY NIGHT INTO FRIDAY...AND THEN APPROACH OF
A FRONTAL SYSTEM EARLY NEXT WEEK.
ON THURSDAY...OUR WEATHER WILL BE DOMINATED BY BROAD HIGH PRESSURE
CENTERED OVER COASTAL NEW ENGLAND. MODELS INDICATE THAT MOISTURE
TRAPPED UNDER SUBSIDENCE INVERSION MAY BE RELUCTANT TO MIX
OUT...ESPECIALLY CONSIDERING STABLE MARINE LAYER INFLUENCE FROM
SOUTHEAST FLOW AROUND THE HIGH. STILL EXPECTING DRY WEATHER...BUT
SHALLOW LAYER OF CLOUDS AND MARINE LAYER PROMPTED ME TO SCALE BACK
HIGH TEMPERATURES A BIT MORE...INTO MAINLY MID TO UPPER 60S
EXCEPT FOR LOW 70S IN THE LAKE PLAIN. POCONOS/WESTERN CATSKILLS
MAY EVEN BE STUCK IN THE LOW 60S FOR HIGHS.
DIVIDING THE COASTAL HIGH...FROM ANOTHER HIGH PRESSURE CENTER OVER
HUDSON BAY...WILL BE A WEAK FRONT THAT WILL DROP THROUGH SOMETIME
AROUND FRIDAY MORNING. I HAVE CENTERED LOW TO MID CHANCE RANGE
POPS AROUND LATE THURSDAY NIGHT-FRIDAY MORNING TIME FRAME.
DIURNALLY UNFAVORABLE TIMING OF FRONTAL PASSAGE...AND MARGINAL AT
BEST INSTABILITY ALONG WITH LIMITED MOISTURE...COMPELLED ME TO
ONLY INCLUDE SLIGHT CHANCE OF THUNDER AT THIS TIME.
HUDSON BAY HIGH PRESSURE WILL THEN BUILD OVER THE NORTHEAST STATES
OVER THE WEEKEND...YIELDING DRY WEATHER...FAIR SKIES...AND AT LEAST
NEAR NORMAL TEMPERATURES THAT SHOULD TREND SLIGHTLY WARMER WITH
TIME. I WAS ABLE TO DELAY NEXT MENTIONABLE CHANCE OF RAIN UNTIL AT
LEAST MONDAY...BUT MODELS DISAGREE ON WHEN THIS ENTERS THE
PICTURE. ECMWF IS FASTER TO FLATTEN UPPER RIDGE AND ALLOWS FRONTAL
SYSTEM IN AS EARLY AS MONDAY...GFS MEANWHILE MAINTAINS RIDGING YET
ALSO ALLOWS SLIGHTLY MORE UNSTABLE AIRMASS INTO REGION WITH TIME
WITH MORE OF A WARM FRONTAL REGIME.
&&
.AVIATION /08Z TUESDAY THROUGH SATURDAY/...
06Z UPDATE...
MAINLY VFR CONDITIONS EXPECTED BUT WITH SOME BRIEF MVFR/IFR POSSIBLE
THIS AFTERNOON IN DEVELOPING SCT -TSRA AS COLD FRONT SINKS SOUTH
ACROSS THE AREA...AT SAME TIME WEAK WAVES TRAVEL WNW TO ESE ALOFT.
BEST CHANCE FOR CONVECTION WILL BE AS FRONT SAGS SOUTH OF KSYR-
KRME DURING PEAK HEATING AND INSTABILITY...FOR KBGM-KITH-KELM-KAVP.
AS FRONT STALLS...LINGERING SHRA/TSRA WILL BE POSSIBLE THROUGH
EVENING. HAVE HANDLED INITIALLY VIA TEMPO GROUPS FOR EXPECTED
DEVELOPING SCT TSRA THIS AFTERNOON...THEN PROB30 TSRA GROUPS INTO
A PORTION OF THE EVENING FOR CENTRAL TO SOUTHERN TERMINALS.
FARTHER NORTH...KSYR-KRME PROB30 GROUPS THIS AFTERNOON...WHERE
THERE IS LESS CONFIDENCE IN INSTABILITY BEING REALIZED IN THE FORM
OF THUNDER. TUESDAY NIGHT...EXPECTING SEVERAL TERMINALS TO SLIP
INTO MVFR CIG AS SHALLOW FRONT CONTINUES TO SAG SOUTH AND/OR SCT
SHRA-TSRA CONTINUES ALONG IT.
OUTLOOK...
LATE TUE NGT/WED...RESTRICTIONS POSSIBLE FROM SCT SHRA/TSRA MAINLY
SOUTH OF KSYR-KRME.
WED NGT/THU...MAINLY VFR.
THU NGT/FRI...RESTRICTIONS POSSIBLE IN SHOWERS. CHANCE TSRA FRI.
FRI NGT/SAT...MAINLY VFR.
&&
.BGM WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NY...NONE.
&&
$$
SYNOPSIS...MDP/PVN
NEAR TERM...PVN
SHORT TERM...PVN
LONG TERM...MDP
AVIATION...MDP
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
417 AM EDT TUE MAY 27 2014
.SYNOPSIS...
A STORM SYSTEM WILL MOVE INTO THE REGION TODAY BRINGING A CHANCE
FOR SHOWERS AND THUNDERSTORMS THROUGH WEDNESDAY AFTERNOON. MAINLY
DRY WEATHER IS FIGURED LATER THIS WEEK THROUGH NEXT WEEKEND...EXCEPT
FOR A CHANCE OF SHOWERS AND THUNDERSTORMS THURSDAY NIGHT INTO
FRIDAY AS A WEAK FRONT MOVES THROUGH THE REGION.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
255 AM UPDATE...
A WK S/WV IS SPARKING OFF A FEW SPRINKLES IN FINGER LKS REGION.
THESE SPRINKLES ARE FALLING OUT OF AN OVERCAST MID-DECK SO NOT
EXPECTING THEM TO AMNT TO MUCH BFR 12Z. AFT 12Z, PW VALUES WL INCRS
TO > 1.30 INCHES WHICH IS APPCHG 2 SD ABV NORMAL FOR THIS TIME OF
YR. LATEST RUC GUIDANCE APPEARS TO BE RIGHT ON TARGET WITH BLENDED
TPW PRODUCT AS OF 06Z, WITH AMNTS < 1 INCH ACRS CWA WITH PW VALUES
NEARING 1.40 INCHES IN NWPA. EXPECT HIGHER PW VALUES TO HEAD EAST
AND INTO AREA THIS AFTN WITH AMNTS BTWN 2-3 SD ABV NORMAL APPCHG
1.60 INCHES.
SFC LOPRES SITTING ALONG ONTARIO/QUEBEC BORDER WITH SFC BNDRYS
EXTNDG EAST AND WEST FM CENTER. THIS LOW DRIFTS SOUTH TDA AND ALL
MODELS BUT THE GFS AGREE ON PLACEMENT OF LOW CNTR OVR SERN ONTARIO
AS OF 18Z THIS AFTN. MAIN CDFNT WL BE LOCATED ACRS SRN PORTIONS OF
ONTARIO BACK INTO LWR MICHIGAN WHILE A BACKDOOR-TYPE COLD FRONT WL
BE PUSHING IN FM NEW ENGLAND LATE AFTN/EVNG HRS AS STRONG HIPRES
BUILDS DOWN INTO THE CANADIAN MARITIMES.
WHILE PW VALUES WL BE ANONYMOUSLY HIGH CORFIDI VECTORS PROGGED TO BE
ARND 10KTS DRG THE DAY. EVEN THO WINDS WL BE RELATIVELY LGT, STILL
SEEMS THAT THERE WL BE ENUF FLOW TO KEEP STORMS MVG TO PREVENT
THREAT FOR MAJOR FLASH FLOODING. CANNOT RULE OUT LOCALLY HEAVY
DOWNPOURS IN STORMS THAT ARE ABLE TO DVLP DUE TO SATD ATMOSPHERE IN
PLACE AND WL WORD AS SUCH IN HWO. CAPE VALUES WL BE TALL AND SKINNY
AND RANGE FM 500-1000 J/KG, THUS POTENTIAL ALSO EXISTS FOR SMALL
HAIL. WITH VRY LITTLE DRY AIR ALOFT EXPECTED TO WORK IN THIS AFTN,
LOOKING AT A LESSOR WIND THREAT THAN HAIL.
MAX TEMPS WL FALL A FEW DEGREES SHORT OF YDA`S VALUES AS EXTENSIVE
CLD CVR WL LIMIT SOLAR INSOLATION. HIGHS WL ONLY REACH INTO THE
U70S/ARND 80 ACRS MAJORITY OF CWA THIS AFTN.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH WEDNESDAY NIGHT/...
300 PM EDT UPDATE...
EARLY TUES MORNING THE PREVIOUS MENTIONED SFC LOW WILL MOVE CLOSER
TO THE BORDER OF WESTERN NY. THE SFC LOW WILL BRING A PRE-FRONTAL
TROUGH/BOUNDARY INTO THE REGION. THIS "BOUNDARY" WILL LINGER OVER
NY/PA THROUGH LATE TUES NIGHT. TUES MORNING A VORT MAX WILL MOVE
AROUND THE OUTER EDGE OF THE UPPR RIDGE AND INTERSECT THIS
BOUNDARY TO CAUSE SHOWERS TO DEVELOP EARLY TUES MORNING. THIS WAVE
AND BOUNDARY ARE EXPECTED TO SLOWLY DRIFT SOUTH THROUGH THE
MORNING HOURS.
TUES AFTERNOON THE THETA-E RIDGE PUSHES INTO THE REGION AND
COPIOUS AMOUNTS MOISTURE WILL BE ADVECTED INTO NY/PA. PWAT VALUES
WILL INCREASE TO AROUND 1.5 INCHES...THIS BEING AROUND ONE
STANDARD DEVIATION ABOVE NORMAL. THE HEAVIEST AXIS OF MOISTURE
WILL REMAIN SOUTH OF THE CWA AND IS ROUGHLY TWO STANDARD
DEVIATIONS ABOVE NORMAL. ML CAPE VALUES WILL INCREASE TO >1000
J/KG OVER PA AND VALUES WILL BE AT OR BELOW 1000 J/KG NORTH OF THE
BORDER OF NY. MODEST MID AND LOW LVL LAPSE RATES WILL BE PRESENT
WHICH WILL ALLOW SHOWERS AND THUNDERSTORMS TO PROLONG ONCE THEY
DEVELOP INTO AFTERNOON. 0-6KM BULK SHEAR WILL BE ROUGHLY 20
KNOTS. DUE TO ALL THE ABOVE MENTIONED FACTORS... THERE WILL BE A CHANCE
FOR HEAVY RAINFALL TUESDAY AFTERNOON. EXPECT SHOWERS AND
THUNDERSTORMS TO BE WIDESPREAD ACROSS THE CWA TOMORROW AFTERNOON
WITH THE GREATEST COVERAGE TO BE CLOSE TO THE BORDER OF NY AND
OVER NORTHEAST PA.
THE SFC LOW WILL CONTINUE TO MOVE SOUTH OVER THE REGION INTO WED
MORNING AND BRING THE FRONT ACROSS THE AREA. MODEL GUIDANCE
HAS DISCREPANCIES IN TIMING OF THE FRONTAL PASSAGE. HOWEVER...ALL
GUIDANCE HAS IT THROUGH THE CWA BY LATE WED MORNING. SHOWERS MAY
LINGER THROUGH WED AFTERNOON AND ARE EXPECTED TO DIMINISH BY WED
NIGHT.
TEMPERATURES DURING THIS TIME PERIOD WILL REMAIN ABOVE NORMAL
REACHING THE 70S. AND LOW TEMPERATURES ARE EXPECTED TO FALL INTO
THE 50S.
&&
.LONG TERM /THURSDAY THROUGH MONDAY/...
415 AM UPDATE...
FAIRLY QUIET PERIOD OF WEATHER...ONLY INTERRUPTED BY A WEAK
FRONTAL PASSAGE THURSDAY NIGHT INTO FRIDAY...AND THEN APPROACH OF
A FRONTAL SYSTEM EARLY NEXT WEEK.
ON THURSDAY...OUR WEATHER WILL BE DOMINATED BY BROAD HIGH PRESSURE
CENTERED OVER COASTAL NEW ENGLAND. MODELS INDICATE THAT MOISTURE
TRAPPED UNDER SUBSIDENCE INVERSION MAY BE RELUCTANT TO MIX
OUT...ESPECIALLY CONSIDERING STABLE MARINE LAYER INFLUENCE FROM
SOUTHEAST FLOW AROUND THE HIGH. STILL EXPECTING DRY WEATHER...BUT
SHALLOW LAYER OF CLOUDS AND MARINE LAYER PROMPTED ME TO SCALE BACK
HIGH TEMPERATURES A BIT MORE...INTO MAINLY MID TO UPPER 60S
EXCEPT FOR LOW 70S IN THE LAKE PLAIN. POCONOS/WESTERN CATSKILLS
MAY EVEN BE STUCK IN THE LOW 60S FOR HIGHS.
DIVIDING THE COASTAL HIGH...FROM ANOTHER HIGH PRESSURE CENTER OVER
HUDSON BAY...WILL BE A WEAK FRONT THAT WILL DROP THROUGH SOMETIME
AROUND FRIDAY MORNING. I HAVE CENTERED LOW TO MID CHANCE RANGE
POPS AROUND LATE THURSDAY NIGHT-FRIDAY MORNING TIME FRAME.
DIURNALLY UNFAVORABLE TIMING OF FRONTAL PASSAGE...AND MARGINAL AT
BEST INSTABILITY ALONG WITH LIMITED MOISTURE...COMPELLED ME TO
ONLY INCLUDE SLIGHT CHANCE OF THUNDER AT THIS TIME.
HUDSON BAY HIGH PRESSURE WILL THEN BUILD OVER THE NORTHEAST STATES
OVER THE WEEKEND...YIELDING DRY WEATHER...FAIR SKIES...AND AT LEAST
NEAR NORMAL TEMPERATURES THAT SHOULD TREND SLIGHTLY WARMER WITH
TIME. I WAS ABLE TO DELAY NEXT MENTIONABLE CHANCE OF RAIN UNTIL AT
LEAST MONDAY...BUT MODELS DISAGREE ON WHEN THIS ENTERS THE
PICTURE. ECMWF IS FASTER TO FLATTEN UPPER RIDGE AND ALLOWS FRONTAL
SYSTEM IN AS EARLY AS MONDAY...GFS MEANWHILE MAINTAINS RIDGING YET
ALSO ALLOWS SLIGHTLY MORE UNSTABLE AIRMASS INTO REGION WITH TIME
WITH MORE OF A WARM FRONTAL REGIME.
&&
.AVIATION /08Z TUESDAY THROUGH SATURDAY/...
06Z UPDATE...
MAINLY VFR CONDITIONS EXPECTED BUT WITH SOME BRIEF MVFR/IFR POSSIBLE
THIS AFTERNOON IN DEVELOPING SCT -TSRA AS COLD FRONT SINKS SOUTH
ACROSS THE AREA...AT SAME TIME WEAK WAVES TRAVEL WNW TO ESE ALOFT.
BEST CHANCE FOR CONVECTION WILL BE AS FRONT SAGS SOUTH OF KSYR-
KRME DURING PEAK HEATING AND INSTABILITY...FOR KBGM-KITH-KELM-KAVP.
AS FRONT STALLS...LINGERING SHRA/TSRA WILL BE POSSIBLE THROUGH
EVENING. HAVE HANDLED INITIALLY VIA TEMPO GROUPS FOR EXPECTED
DEVELOPING SCT TSRA THIS AFTERNOON...THEN PROB30 TSRA GROUPS INTO
A PORTION OF THE EVENING FOR CENTRAL TO SOUTHERN TERMINALS.
FARTHER NORTH...KSYR-KRME PROB30 GROUPS THIS AFTERNOON...WHERE
THERE IS LESS CONFIDENCE IN INSTABILITY BEING REALIZED IN THE FORM
OF THUNDER. TUESDAY NIGHT...EXPECTING SEVERAL TERMINALS TO SLIP
INTO MVFR CIG AS SHALLOW FRONT CONTINUES TO SAG SOUTH AND/OR SCT
SHRA-TSRA CONTINUES ALONG IT.
OUTLOOK...
LATE TUE NGT/WED...RESTRICTIONS POSSIBLE FROM SCT SHRA/TSRA MAINLY
SOUTH OF KSYR-KRME.
WED NGT/THU...MAINLY VFR.
THU NGT/FRI...RESTRICTIONS POSSIBLE IN SHOWERS. CHANCE TSRA FRI.
FRI NGT/SAT...MAINLY VFR.
&&
.BGM WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NY...NONE.
&&
$$
SYNOPSIS...MDP/PVN
NEAR TERM...PVN
SHORT TERM...KAH
LONG TERM...MDP
AVIATION...MDP
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
255 AM EDT TUE MAY 27 2014
.SYNOPSIS...
PARTLY CLOUDY SKIES WILL EXIST OVERNIGHT. A STORM SYSTEM WILL
MOVE INTO THE REGION TODAY BRINGING A CHANCE FOR SHOWERS AND
THUNDERSTORMS THROUGH WEDNESDAY AFTERNOON. HIGH PRESSURE WILL
RETURN THURSDAY BRINGING DRY WEATHER AGAIN.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
255 AM UPDATE...
A WK S/WV IS SPARKING OFF A FEW SPRINKLES IN FINGER LKS REGION.
THESE SPRINKLES ARE FALLING OUT OF AN OVERCAST MID-DECK SO NOT
EXPECTING THEM TO AMNT TO MUCH BFR 12Z. AFT 12Z, PW VALUES WL INCRS
TO > 1.30 INCHES WHICH IS APPCHG 2 SD ABV NORMAL FOR THIS TIME OF
YR. LATEST RUC GUIDANCE APPEARS TO BE RIGHT ON TARGET WITH BLENDED
TPW PRODUCT AS OF 06Z, WITH AMNTS < 1 INCH ACRS CWA WITH PW VALUES
NEARING 1.40 INCHES IN NWPA. EXPECT HIGHER PW VALUES TO HEAD EAST
AND INTO AREA THIS AFTN WITH AMNTS BTWN 2-3 SD ABV NORMAL APPCHG
1.60 INCHES.
SFC LOPRES SITTING ALONG ONTARIO/QUEBEC BORDER WITH SFC BNDRYS
EXTNDG EAST AND WEST FM CENTER. THIS LOW DRIFTS SOUTH TDA AND ALL
MODELS BUT THE GFS AGREE ON PLACEMENT OF LOW CNTR OVR SERN ONTARIO
AS OF 18Z THIS AFTN. MAIN CDFNT WL BE LOCATED ACRS SRN PORTIONS OF
ONTARIO BACK INTO LWR MICHIGAN WHILE A BACKDOOR-TYPE COLD FRONT WL
BE PUSHING IN FM NEW ENGLAND LATE AFTN/EVNG HRS AS STRONG HIPRES
BUILDS DOWN INTO THE CANADIAN MARITIMES.
WHILE PW VALUES WL BE ANONYMOUSLY HIGH CORFIDI VECTORS PROGGED TO BE
ARND 10KTS DRG THE DAY. EVEN THO WINDS WL BE RELATIVELY LGT, STILL
SEEMS THAT THERE WL BE ENUF FLOW TO KEEP STORMS MVG TO PREVENT
THREAT FOR MAJOR FLASH FLOODING. CANNOT RULE OUT LOCALLY HEAVY
DOWNPOURS IN STORMS THAT ARE ABLE TO DVLP DUE TO SATD ATMOSPHERE IN
PLACE AND WL WORD AS SUCH IN HWO. CAPE VALUES WL BE TALL AND SKINNY
AND RANGE FM 500-1000 J/KG, THUS POTENTIAL ALSO EXISTS FOR SMALL
HAIL. WITH VRY LITTLE DRY AIR ALOFT EXPECTED TO WORK IN THIS AFTN,
LOOKING AT A LESSOR WIND THREAT THAN HAIL.
MAX TEMPS WL FALL A FEW DEGREES SHORT OF YDA`S VALUES AS EXTENSIVE
CLD CVR WL LIMIT SOLAR INSOLATION. HIGHS WL ONLY REACH INTO THE
U70S/ARND 80 ACRS MAJORITY OF CWA THIS AFTN.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH THURSDAY/...
300 PM EDT UPDATE...
EARLY TUES MORNING THE PREVIOUS MENTIONED SFC LOW WILL MOVE CLOSER
TO THE BORDER OF WESTERN NY. THE SFC LOW WILL BRING A PRE-FRONTAL
TROUGH/BOUNDARY INTO THE REGION. THIS "BOUNDARY" WILL LINGER OVER
NY/PA THROUGH LATE TUES NIGHT. TUES MORNING A VORT MAX WILL MOVE
AROUND THE OUTER EDGE OF THE UPPR RIDGE AND INTERSECT THIS
BOUNDARY TO CAUSE SHOWERS TO DEVELOP EARLY TUES MORNING. THIS WAVE
AND BOUNDARY ARE EXPECTED TO SLOWLY DRIFT SOUTH THROUGH THE
MORNING HOURS.
TUES AFTERNOON THE THETA-E RIDGE PUSHES INTO THE REGION AND
COPIOUS AMOUNTS MOISTURE WILL BE ADVECTED INTO NY/PA. PWAT VALUES
WILL INCREASE TO AROUND 1.5 INCHES...THIS BEING AROUND ONE
STANDARD DEVIATION ABOVE NORMAL. THE HEAVIEST AXIS OF MOISTURE
WILL REMAIN SOUTH OF THE CWA AND IS ROUGHLY TWO STANDARD
DEVIATIONS ABOVE NORMAL. ML CAPE VALUES WILL INCREASE TO >1000
J/KG OVER PA AND VALUES WILL BE AT OR BELOW 1000 J/KG NORTH OF THE
BORDER OF NY. MODEST MID AND LOW LVL LAPSE RATES WILL BE PRESENT
WHICH WILL ALLOW SHOWERS AND THUNDERSTORMS TO PROLONG ONCE THEY
DEVELOP INTO AFTERNOON. 0-6KM BULK SHEAR WILL BE ROUGHLY 20
KNOTS. DUE TO ALL THE ABOVE MENTIONED FACTORS... THERE WILL BE A CHANCE
FOR HEAVY RAINFALL TUESDAY AFTERNOON. EXPECT SHOWERS AND
THUNDERSTORMS TO BE WIDESPREAD ACROSS THE CWA TOMORROW AFTERNOON
WITH THE GREATEST COVERAGE TO BE CLOSE TO THE BORDER OF NY AND
OVER NORTHEAST PA.
THE SFC LOW WILL CONTINUE TO MOVE SOUTH OVER THE REGION INTO WED
MORNING AND BRING THE FRONT ACROSS THE AREA. MODEL GUIDANCE
HAS DISCREPANCIES IN TIMING OF THE FRONTAL PASSAGE. HOWEVER...ALL
GUIDANCE HAS IT THROUGH THE CWA BY LATE WED MORNING. SHOWERS MAY
LINGER THROUGH WED AFTERNOON AND ARE EXPECTED TO DIMINISH BY WED
NIGHT.
HIGH PRESSURE WILL BUILD INTO THE REGION FROM THE EAST ON
THURSDAY. EXPECT THURSDAY TO BE DRY BUT CLOUDY.
TEMPERATURES DURING THIS TIME PERIOD WILL REMAIN ABOVE NORMAL
REACHING THE 70S. AND LOW TEMPERATURES ARE EXPECTED TO FALL
INTO THE 50S.
&&
.LONG TERM /THURSDAY NIGHT THROUGH MONDAY/...
MEDIUM RANGE MODELS ARE IN GOOD AGREEMENT THROUGH THE EARLY PART
OF THE UPCOMING WEEKEND THEN SHOW SIGNIFICANT DIFFERENCES BY
SUNDAY/MONDAY. IN GENERAL FOLLOWED WPC GUIDANCE WHICH IS A
GFS/ECMWF BLEND.
INITIALLY PERIOD BEGINS WITH NORTHWEST UPPER LEVEL FLOW AS TROF
AXIS WILL RESIDE OVER EASTERN CANADA/NEW ENGLAND. SHORT WAVES
EMBEDDED IN THIS FLOW COMBINED WITH A COLD FRONTAL PASSAGE ON
FRIDAY WILL BRING THE CHANCE FOR SHOWERS THURSDAY NIGHT AND
SHOWERS AND THUNDERSTORMS ON FRIDAY. FRIDAY NIGHT THROUGH SUNDAY,
SFC HIGH PRES IN THE VCNTY AND RISING HEIGHTS ALOFT WILL MAKE FOR
A DRY PERIOD WITH SEASONAL TEMPERATURES. SUNDAY NIGHT INTO MONDAY
A SYSTEM IN THE WESTERN GREAT LAKES WILL START IMPACTING OUR
WEATHER SO WILL CARRY CHC POPS FOR SHOWERS/THUNDERSTORMS.
&&
.AVIATION /07Z TUESDAY THROUGH SATURDAY/...
06Z UPDATE...
MAINLY VFR CONDITIONS EXPECTED BUT WITH SOME BRIEF MVFR/IFR POSSIBLE
THIS AFTERNOON IN DEVELOPING SCT -TSRA AS COLD FRONT SINKS SOUTH
ACROSS THE AREA...AT SAME TIME WEAK WAVES TRAVEL WNW TO ESE ALOFT.
BEST CHANCE FOR CONVECTION WILL BE AS FRONT SAGS SOUTH OF KSYR-
KRME DURING PEAK HEATING AND INSTABILITY...FOR KBGM-KITH-KELM-KAVP.
AS FRONT STALLS...LINGERING SHRA/TSRA WILL BE POSSIBLE THROUGH
EVENING. HAVE HANDLED INITIALLY VIA TEMPO GROUPS FOR EXPECTED
DEVELOPING SCT TSRA THIS AFTERNOON...THEN PROB30 TSRA GROUPS INTO
A PORTION OF THE EVENING FOR CENTRAL TO SOUTHERN TERMINALS.
FARTHER NORTH...KSYR-KRME PROB30 GROUPS THIS AFTERNOON...WHERE
THERE IS LESS CONFIDENCE IN INSTABILITY BEING REALIZED IN THE FORM
OF THUNDER. TUESDAY NIGHT...EXPECTING SEVERAL TERMINALS TO SLIP
INTO MVFR CIG AS SHALLOW FRONT CONTINUES TO SAG SOUTH AND/OR SCT
SHRA-TSRA CONTINUES ALONG IT.
OUTLOOK...
LATE TUE NGT/WED...RESTRICTIONS POSSIBLE FROM SCT SHRA/TSRA MAINLY
SOUTH OF KSYR-KRME.
WED NGT/THU...MAINLY VFR.
THU NGT/FRI...RESTRICTIONS POSSIBLE IN SHOWERS. CHANCE TSRA FRI.
FRI NGT/SAT...MAINLY VFR.
&&
.BGM WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NY...NONE.
&&
$$
SYNOPSIS...KAH/PVN
NEAR TERM...PVN
SHORT TERM...KAH
LONG TERM...RRM
AVIATION...MDP
AREA FORECAST DISCUSSION
NWS RALEIGH NC
920 PM EDT WED MAY 28 2014
.SYNOPSIS...A WARM AND MOIST AIRMASS WILL PERSIST ACROSS THE REGION
THIS EVENING. A BACK DOOR COLD FRONT WILL MOVE SOUTHWARD INTO
CENTRAL NORTH CAROLINA LATE TONIGHT...AND WILL STALL ACROSS SOUTHERN
PORTIONS OF THE STATE ON THURSDAY BEFORE MOVING SOUTH OF THE AREA ON
FRIDAY. HIGH PRESSURE WILL EXTEND INTO THE REGION FROM THE NORTHEAST
OVER THE WEEKEND.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 920 PM WEDNESDAY...
PRIMARY CHANGE THIS EVENING IS A REORIENTATION OF PRECIP CHANCES
ACROSS THE CWA TO INCREASE THEM ACROSS THE NORTHEAST QUARTER OF THE
CWA AND DECREASE THEM ELSEWHERE. AS OF 9 PM THE BACKDOOR SURFACE
FRONT EXTENDED FROM JUST SOUTH OF CHI ACROSS FAR NRN IN/OH AND SW
PA/DC/DELMARVA. AS ONE MIGHT EXPECT WITHIN A REGIME OF MARGINAL TO
MODERATE INSTABILITY AND VERY WEAK SHEAR... THE LATEST SURFACE
ANALYSIS SHOWS NUMEROUS WEAK BOUNDARIES AND CONVECTIVE OUTFLOWS
ACROSS THE REGION... THE MOST PROFOUND OF WHICH NOW STRETCHES FROM
WEST CENTRAL VA SE TO SE VA AND NE NC WITH NUMEROUS SHOWERS AND
STORMS AND THE ASSOCIATED COLD POOL PROPAGATING GENERALLY
SOUTHWARD... OUT AHEAD OF THE SYNOPTIC FRONT. EARLIER HRRR RUNS
TODAY HAVE NOT DONE VERY WELL BUT THE LATEST HRRR RUN APPEARS TO BE
HANDLING THE ONGOING CONVECTION TO OUR NNE WELL... AND IT PROGRESSES
THIS ACTIVITY SOUTHWARD AND SE OVER THE NORTHEAST CWA... IN LINE
WITH EXTRAPOLATION OF EXISTING FEATURES. THE AIR MASS IN THIS REGION
REMAINS MODERATELY UNSTABLE WITH MLCAPE VALUES OF 1500-2000 J/KG
ACCORDING TO THE SPC MESOANALYSIS... AND WHILE CINH IS STARTING TO
CREEP UP... LAPSE RATES REMAIN HIGH ENOUGH WITH REMAINING ELEVATED
CAPE TO SUPPORT THE ONGOING CONVECTION AS IT TRANSLATES INTO THE
CENTRAL NC. HAVE RAISED POPS TO SCATTERED FROM RALEIGH TO THE NORTH
AND EAST... PUSHING SOUTHEAST THROUGH THE NIGHT... WITH ISOLATED
POPS SURROUNDING THIS AREA... AND LITTLE TO NO POP OVER THE WRN AND
SW CWA. WITH A TREND TOWARD MOSTLY CLOUDY SKIES... EXPECT LOWS OF 66-
71. -GIH
&&
.SHORT TERM /THURSDAY AND THURSDAY NIGHT/...
AS OF 245 PM WEDNESDAY...
THE BACKDOOR COLD FRONT SLIDING TOWARD CENTRAL NC FROM THE NORTH
WILL STALL OUT AROUND THE VA/NC BORDER. SURFACE CONVERGENCE BETWEEN
THE HIGH TO THE NE AND LOW TO THE SW...AND THE RESULTANT MOISTURE
AND TEMPERATURE BOUNDARIES...WILL RESULT IN INCREASED CHANCES FOR
CONVECTION...ESPECIALLY ACROSS THE SOUTH WHERE THE BEST MOISTURE AND
HIGHEST TEMPS ARE EXPECTED. THE BEST UPPER LEVEL FORCING WILL OCCUR
AROUND/AFTER 00Z FRIDAY AS SHORTWAVE ENERGY MOVES AROUND THE BASE OF
THE UPPER LEVEL TROUGH AND SWINGS THROUGH THE AREA. SHEAR AND
INSTABILITY PARAMETERS ARE EXPECTED TO BE SIMILAR TO TUESDAY AND
WEDNESDAY...WITH PWATS IN THE 1.50-1.75 INCH RANGE. THUS...AN
ISOLATED SEVERE STORM OR TWO AND HEAVY RAIN CANNOT BE RULED
OUT...WITH THE BEST CHANCES ACROSS THE SOUTH.
&&
.LONG TERM /FRIDAY THROUGH WEDNESDAY/...
AS OF 245 PM WEDNESDAY...
THE FRONT WILL LINGER NEAR THE SOUTHERN PORTION OF THE FORECAST AREA
ON FRIDAY...BEFORE BEING PUSHED EVEN FURTHER SOUTH OVER THE WEEKEND
BY HIGH PRESSURE BUILDING DOWN OUT OF THE NORTHEAST. GOOD MOISTURE
WILL REMAIN OVER THE AREA (PWAT VALUES NEAR 1.25-1.75 INCHES...
HIGHEST ACROSS THE SOUTH) BEFORE DRIER AIR FILTERS IN LATE FRIDAY
INTO SATURDAY. AS A RESULT... DECENT PRECIP CHANCES WILL ONCE AGAIN
OCCUR ACROSS THE AREA ON FRIDAY (HIGHEST ACROSS THE SOUTH IN THE
VICINITY OF THE FRONT AND BEST DESTABILIZATION). TEMPS WILL
GENERALLY BE IN THE UPPER 70S TO LOWER 80S.
THEN...FAIRLY STRONG HIGH PRESSURE (~1025 MB) WILL BUILD DOWN THE
EAST COAST OVER THE WEEKEND...PUSHING THE BOUNDARY EVEN FURTHER
SOUTH. THIS WILL VIRTUALLY BRING AN END TO OUR PRECIP CHANCES AS
STABLE NORTHEASTERLY FLOW DOMINATES. HIGH PRESSURE WILL THEN
DOMINATE THROUGH EARLY NEXT WEEK...SHIFTING OFFSHORE BY TUESDAY.
THEREFORE...AM EXPECTING THE AREA TO BE MOSTLY DRY...WITH MAYBE SOME
DIURNAL TYPE PRECIP RETURNING TUESDAY INTO WEDNESDAY AS MOISTURE
GRADUALLY INCREASES IN THE INCREASING RETURN FLOW...ESPECIALLY
ACROSS THE WESTERN PORTIONS OF THE FORECAST AREA. TEMPS WILL BE
SLIGHTLY BELOW NORMAL FOR THE WEEKEND...BEFORE GRADUALLY MODERATING
NEXT WEEK TO BACK TO ABOVE NORMAL BY TUESDAY.
&&
.AVIATION /00Z THURSDAY THROUGH MONDAY/...
AS OF 740 PM WEDNESDAY...
24 HOUR TAF PERIOD: VFR CONDITIONS SHOULD PREVAIL AT MOST LOCATIONS
THROUGH AT LEAST THE FIRST 10 HOURS OF THE TAF PERIOD BEFORE ADVERSE
CONDITIONS TAKE OVER AT MOST LOCATIONS. CEILINGS WILL BE THE MAIN
THREAT TO VFR CONDITIONS AS A FRONT APPROACHES FROM THE NORTH. WINDS
WILL BE VARIABLE OVERNIGHT AT LESS THAN 5 KTS EARLY ON BUT THEN
PICKING UP TO 5-10 KTS AS THE FRONT STARTS TO MOVE THROUGH DURING
THE EARLY MORNING HOURS. WINDS WILL SHIFT AROUND TO NORTHEASTERLY
AND CEILINGS WILL DROP FIRST TO IFR IN SOME LOCATIONS BUT THEN
SETTLE IN AT MVFR LEVELS AFTER 12Z. CEILINGS MAY REMAIN MVFR THROUGH
THE TAF PERIOD IN MOST LOCATIONS EXCEPT FOR KFAY WHICH COULD STAY
VFR MUCH LONGER. SOME MVFR VISIBILITIES ARE ALSO POSSIBLE AT ALL
SITES ON THURSDAY. THAT BEING SAID...CONFIDENCE IN CONTINUOUS
ADVERSE CONDITIONS IS ONLY MODERATE. THERE COULD BE BREAKOUT PERIODS
OF VFR THROUGH THE DAY TOMORROW DEPENDENT ON THE LOCATION OF SHOWERS
AND THUNDERSTORMS WHICH COULD BE AREA WIDE BY TOMORROW AFTERNOON AND
EVENING.
LONG TERM: SUB-VFR CEILINGS WILL BE POSSIBLE EARLY FRIDAY MORNING
BEFORE VFR CONDITIONS RETURN FOR THE WEEKEND AND EARLY NEXT WEEK.
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...BLAES
NEAR TERM...HARTFIELD
SHORT TERM...KC
LONG TERM...KRD
AVIATION...ELLIS
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
648 AM EDT TUE MAY 27 2014
.SYNOPSIS...
WARM AND HUMID WEATHER IS EXPECTED OVER THE NEXT SEVERAL DAYS
WHICH MAY GIVE RISE TO SCATTERED MAINLY AFTERNOON THUNDERSTORMS. A
BACK DOOR COLD FRONT WILL SLOWLY SINK SOUTH ACROSS THE AREA
THURSDAY INTO FRIDAY. HIGH PRESSURE THEN BUILDS IN FROM THE NORTH
OVER THE WEEKEND KEEPING THE AREA RAIN FREE.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 650 AM TUESDAY...A NARROW UPPER LEVEL RIDGE EXTENDING FROM THE
SOUTHERN APPALACHIANS TO THE FLORIDA PANHANDLE WILL DEAMPLIFY TODAY
AS IT MOVES EAST TOWARD THE COAST THIS EVENING. IN THE LOW LEVELS
BERMUDA HIGH PRESSURE WILL EXTEND A RIDGE AXIS WESTWARD ACROSS
NORTHERN FLORIDA WHILE A PIEDMONT TROUGH DEVELOPS ACROSS THE
INTERIOR CAROLINAS. A WEAK UPPER DISTURBANCE NOW CROSSING INTERSTATE
95 HAS BEEN EARLIER PRODUCED ISOLATED SHOWERS ACROSS THE PIEDMONT.
AS THIS DISTURBANCE MAKES IT WAY EASTWARD TO THE COAST BY LATE
MORNING MID CLOUDS WILL INCREASE ALTHOUGH PRECIP CHANCES APPEAR
QUITE SMALL.
THE POTENTIAL FOR MORE WIDESPREAD SURFACE-BASED CONVECTION WILL
DEVELOP THIS AFTERNOON AS SURFACE-BASED CAPE INCREASES TO 1500 J/KG.
ALTHOUGH THIS MORNING`S WEAK UPPER DISTURBANCE WILL BE OFFSHORE BY
AFTERNOON...A DIFFERENTIAL HEATING BOUNDARY ALONG THE PIEDMONT/
SANDHILLS INTERFACE PLUS THE SEABREEZE COULD INITIATE NEW SHOWERS
AND STORMS IN THIS UNSTABLE AIRMASS. THE NAM IS MUCH MORE AGGRESSIVE
WITH THIS POTENTIAL THAN THE GFS...WITH THE HRRR AND RUC IN THE
MIDDLE. MY FORECAST POPS ARE AROUND 30 PERCENT...BUT A LITTLE LOWER
IN THE WILMINGTON AREA WHERE PRECIPITABLE WATER VALUES WILL REMAIN
LOWEST. HIGH TEMPERATURES SHOULD REACH THE MID TO UPPER 80S...EXCEPT
AROUND 90 IN THE DARLINGTON-BENNETTSVILLE AREA.
AFTERNOON CONVECTION SHOULD DIE AWAY QUICKLY THIS EVENING...ALTHOUGH
CLOUD COVER MAY REMAIN A BIT MORE EXTENSIVE OVERNIGHT THAN WE HAVE
SEEN THE PAST SEVERAL NIGHTS GIVEN THE INCREASE IN MID-LEVEL
MOISTURE AHEAD OF AN UPPER LEVEL LOW OVER THE WESTERN GULF COAST.
LOWS SHOULD FALL INTO THE UPPER 60S INLAND TO NEAR 70 ON THE COAST.
&&
.SHORT TERM /WEDNESDAY THROUGH THURSDAY NIGHT/...
AS OF 3 AM TUESDAY...WEDNESDAY FINDS AN UPPER TROUGH SLOWLY
PROGRESSING EAST ACROSS THE GULF STATES. AHEAD OF THIS FEATURE A
SHORTWAVE RIDGE WILL REMAIN POKED UP OVER THE CAROLINAS. THE RIDGE
WILL NOT BE SUFFICIENTLY STRONG TO CAP OFF ALL CONVECTION ACROSS THE
REGION BUT COVERAGE MAY BE AT A RELATIVE MINIMUM COMPARED TO OTHER
DAYS OF THE FCST. PIEDMONT TROUGH TO OUR WEST MORE A FOCUS ACCORDING
TO WRF WHEREAS GFS SEEMS TO LIKE GFS BETTER. GIVEN THAT STORM
MOTION WILL HAVE A GOOD EASTERLY COMPONENT FEEL THAT THE MOS POPS
GENERALLY AROUND 40 WILL SUFFICE AREA-WIDE. TEMPERATURES WILL BE A
FEW DEGREES ABOVE CLIMO WITH MOST PLACES WITHIN A FEW DEGREES OF 90.
A BACKDOOR COLD FRONT WILL SLOWLY SAG SOUTHWARD ACROSS THE REGION ON
THURSDAY. THIS WILL BE THE MAIN FOCUS FOR CONVECTION AND SO PICKING
OUT FAVORED AREAS WILL DEPEND ON THE SPEED/LOCATION OF THE BOUNDARY
SINCE PLACES SHOULD TEND TO STABILIZE TO ITS NORTH.
&&
.LONG TERM /FRIDAY THROUGH MONDAY/...
AS OF 3 AM TUESDAY...MAIN RAIN CHANCES SHIFTING SOUTH ON FRIDAY
ALONG WITH POSITION OF BOUNDARY...ALTHOUGH ITS HARD TO TELL THIS FAR
OUT IN TIME HOW MUCH DRYING OCCURS OVER NRN ZONES. WITH AN
ADDITIONAL SHIFT OF EVERYTHING TO THE SOUTH THANKS TO THE DEEPENING
UPPER TROUGH OFF THE NE COAST SATURDAY MAY BE DRY FOR ALL BUT
SOUTHERNMOST AREAS. THIS SETUP LASTS INTO SUNDAY...GENERALLY
RAIN-FREE CONDITIONS WITH TEMPERATURES A LITTLE BELOW CLIMO. HIGH
BUILDS OVERHEAD ON MONDAY WHICH SHOULD FAVOR A RETURN OF TEMPS NEAR
NORMAL IF NOT A TAD HIGHER.
&&
.AVIATION /12Z TUESDAY THROUGH SATURDAY/...
AS OF 12Z...ATMOSPHERE WILL CONTINUE TO MOISTEN UP OVER THE NEXT 24
HOURS WITH PRECIPITABLE WATER VALUES EXPECTED TO RISE FROM ABOUT 1.3
INCHES TO AROUND 1.7 INCHES BY THE END OF THE FORECAST PERIOD. HIGH
PRESSURE WILL CONTINUE TO RECEDE WITH A WEAK THERMAL TROUGH EXPECTED
THIS AFTERNOON. GUSTY SOUTHWEST WINDS WILL CONTINUE TO TRANSPORT
MOISTURE. SCATTERED CONVECTION IS EXPECTED TO DEVELOP BY EARLY
AFTERNOON. THE COASTAL TERMINALS COULD SEE SOME CONVECTION
EARLY...BUT THE SEA BREEZE BOUNDARY SHOULD KEEP THE ACTIVITY WEST OF
THE TERMINALS BY 20Z. INLAND TERMINALS WILL HAVE CONVECTION ON OR
NEARBY THE AREA THROUGH EARLY EVENING...DIMINISHING DIURNALLY BY
02Z. SOUTHWEST FLOW OVERNIGHT WILL LIKELY BE TOO STRONG TO SUPPORT
FOG.
EXTENDED OUTLOOK...SCATTERED SHOWERS/TSTMS EXPECTED WEDNESDAY
THROUGH FRIDAY...MAINLY IN THE AFTN HOURS...WITH BRIEF AND ISOLATED
PERIODS OF SUB-VFR CONDITIONS POSSIBLE. SATURDAY WILL BE DRIER AS A
COLD FRONT FINALLY DROPS SOUTHWARD INTO THE CAROLINAS.
&&
.MARINE...
NEAR TERM /THROUGH TONIGHT/...
AS OF 650 AM TUESDAY...HIGH PRESSURE OVER BERMUDA WILL EXTEND A
RIDGE AXIS WESTWARD ALONG 30 DEGREES NORTH LATITUDE TODAY. A
PIEDMONT TROUGH OVER THE INTERIOR CAROLINAS WILL HELP COMPRESS THE
PRESSURE GRADIENT WITH SUSTAINED WINDS AVERAGING 15 KNOTS. ADD TO
THAT THE AFTERNOON SEABREEZE AND WE COULD SEE WINDS NEARSHORE
INCREASE TO 20 KNOTS DURING THE AFTERNOON AND EARLY EVENING HOURS.
MARINE MOS GUIDANCE BASED OFF THE 00Z GFS EVEN HAS 24 KNOTS AT
WRIGHTSVILLE BEACH AT 21Z THIS AFTERNOON...WHILE THE 06Z GFS HAS
INCREASED THAT TO 26 KNOTS! WHILE MY FORECAST IS NOT QUITE THAT
STRONG... IT STILL SHOULD BECOME QUITE BREEZY NEAR THE COAST AND
ACROSS THE NEARSHORE WATERS THIS AFTERNOON.
ISOLATED SHOWERS AND THUNDERSTORMS WILL BECOME POSSIBLE THIS
AFTERNOON. ALTHOUGH LOW-LEVEL WINDS WILL BE ONSHORE THROUGH THE
DAY...WINDS UP AT CLOUD LEVEL WILL BE FROM THE WEST PUSHING ANY
POTENTIAL SHOWERS/T-STORMS EASTWARD. SEAS CURRENTLY 2-3 FEET SHOULD
BUILD TO 3-4 FEET BY LATE IN THE DAY.
SHORT TERM /WEDNESDAY THROUGH THURSDAY NIGHT/...
AS OF 3 AM TUESDAY...A BIT OF A PREFRONTAL FLOW REGIME IN PLACE ON
WEDNESDAY. MORE ACCURATE TO SAY THAT SW WINDS THE RESULT OF PIEDMONT
TROUGH SINCE THE ACTUAL BACKDOOR FRONT WILL BE WELL TO THE NORTH. IT
WILL DROP INTO THE REGION ON THURSDAY HOWEVER AND BE QUITE SLOW TO
MAKE ITS WAY SOUTHWARD. JUST AHEAD OF THE FRONT WINDS WILL TEND TO
GO LIGHT AND VARIABLE. THEN A N TO NE FLOW WILL SPREAD SOUTHWARD
ACROSS THE MARINE ZONES.
LONG TERM /FRIDAY THROUGH SATURDAY/...
AS OF 3 AM TUESDAY...COASTAL ZONES MAY END UP BISECTED NORTH TO
SOUTH BY A BACK DOOR COLD FRONT FOR MUCH OF FRIDAY. A LIGHT NE WIND
WILL THUS SPREAD ACROSS NORTHERN ZONES WITH SOUTHWESTERLY WIND OVER
SOUTHERN ZONES AND AN AREA OF LIGHT AND VARIABLE WINDS BETWEEN. SEAS
THUS REMAIN QUITE TAME...GENERALLY JUST 2 FT OR LESS. HIGHER WINDS
AND SEAS WILL BECOME ESTABLISHED ON SATURDAY AS THE BOUNDARY SINKS
FURTHER TO THE SOUTH AND HIGH PRESSURE MANAGES TO BUILD IN FROM THE
NORTH. A NE GRADIENT WILL TIGHTEN LEADING TO THE DETERIORATED
CONDITIONS BUT NO ADVISORY OR EVEN HEADLINES EXPECTED.
&&
.ILM WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
NC...NONE.
MARINE...NONE.
&&
$$
NEAR TERM...TRA
SHORT TERM...MBB
LONG TERM...MBB
AVIATION...43
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
642 AM EDT TUE MAY 27 2014
.SYNOPSIS...
WARM AND HUMID WEATHER IS EXPECTED OVER THE NEXT SEVERAL DAYS
WHICH MAY GIVE RISE TO SCATTERED MAINLY AFTERNOON THUNDERSTORMS. A
BACK DOOR COLD FRONT WILL SLOWLY SINK SOUTH ACROSS THE AREA
THURSDAY INTO FRIDAY. HIGH PRESSURE THEN BUILDS IN FROM THE NORTH
OVER THE WEEKEND KEEPING THE AREA RAIN FREE.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 3 AM TUESDAY...A NARROW UPPER LEVEL RIDGE EXTENDING FROM THE
SOUTHERN APPALACHIANS TO THE FLORIDA PANHANDLE WILL DEAMPLIFY TODAY
AS IT MOVES EAST TOWARD THE COAST THIS EVENING. IN THE LOW LEVELS
BERMUDA HIGH PRESSURE WILL EXTEND A RIDGE AXIS WESTWARD ACROSS
NORTHERN FLORIDA WHILE A PIEDMONT TROUGH DEVELOPS ACROSS THE
INTERIOR CAROLINAS. A WEAK UPPER DISTURBANCE CURRENTLY JUST WEST OF
INTERSTATE 95 HAS BEEN PRODUCING ISOLATED SHOWERS ACROSS THE
PIEDMONT EARLY THIS MORNING. AS THIS DISTURBANCE MAKES IT WAY
EASTWARD TO THE COAST BY LATE MORNING CLOUDS WILL INCREASE ALTHOUGH
PRECIP CHANCES APPEAR QUITE SMALL.
THE POTENTIAL FOR MORE WIDESPREAD SURFACE-BASED CONVECTION WILL
DEVELOP THIS AFTERNOON AS SURFACE-BASED CAPE INCREASES TO 1500 J/KG.
ALTHOUGH THIS MORNING`S WEAK UPPER DISTURBANCE WILL BE OFFSHORE BY
AFTERNOON...A DIFFERENTIAL HEATING BOUNDARY ALONG THE PIEDMONT/
SANDHILLS INTERFACE PLUS THE SEABREEZE COULD INITIATE NEW SHOWERS
AND STORMS IN THIS UNSTABLE AIRMASS. THE NAM IS MUCH MORE AGGRESSIVE
WITH THIS POTENTIAL THAN THE GFS...WITH THE HRRR AND RUC IN THE
MIDDLE. MY FORECAST POPS ARE AROUND 30 PERCENT...BUT A LITTLE LOWER
IN THE WILMINGTON AREA WHERE PRECIPITABLE WATER VALUES WILL REMAIN
LOWEST. HIGH TEMPERATURES SHOULD REACH THE MID TO UPPER 80S...EXCEPT
AROUND 90 IN THE DARLINGTON-BENNETTSVILLE AREA.
AFTERNOON CONVECTION SHOULD DIE AWAY QUICKLY THIS EVENING...ALTHOUGH
CLOUD COVER MAY REMAIN A BIT MORE EXTENSIVE OVERNIGHT THAN WE HAVE
SEEN THE PAST SEVERAL NIGHTS GIVEN THE INCREASE IN MID-LEVEL
MOISTURE AHEAD OF AN UPPER LEVEL LOW OVER THE WESTERN GULF COAST.
LOWS SHOULD FALL INTO THE UPPER 60S INLAND TO NEAR 70 ON THE COAST.
&&
.SHORT TERM /WEDNESDAY THROUGH THURSDAY NIGHT/...
AS OF 3 AM TUESDAY...WEDNESDAY FINDS AN UPPER TROUGH SLOWLY
PROGRESSING EAST ACROSS THE GULF STATES. AHEAD OF THIS FEATURE A
SHORTWAVE RIDGE WILL REMAIN POKED UP OVER THE CAROLINAS. THE RIDGE
WILL NOT BE SUFFICIENTLY STRONG TO CAP OFF ALL CONVECTION ACROSS THE
REGION BUT COVERAGE MAY BE AT A RELATIVE MINIMUM COMPARED TO OTHER
DAYS OF THE FCST. PIEDMONT TROUGH TO OUR WEST MORE A FOCUS ACCORDING
TO WRF WHEREAS GFS SEEMS TO LIKE GFS BETTER. GIVEN THAT STORM
MOTION WILL HAVE A GOOD EASTERLY COMPONENT FEEL THAT THE MOS POPS
GENERALLY AROUND 40 WILL SUFFICE AREA-WIDE. TEMPERATURES WILL BE A
FEW DEGREES ABOVE CLIMO WITH MOST PLACES WITHIN A FEW DEGREES OF 90.
A BACKDOOR COLD FRONT WILL SLOWLY SAG SOUTHWARD ACROSS THE REGION ON
THURSDAY. THIS WILL BE THE MAIN FOCUS FOR CONVECTION AND SO PICKING
OUT FAVORED AREAS WILL DEPEND ON THE SPEED/LOCATION OF THE BOUNDARY
SINCE PLACES SHOULD TEND TO STABILIZE TO ITS NORTH.
&&
.LONG TERM /FRIDAY THROUGH MONDAY/...
AS OF 3 AM TUESDAY...MAIN RAIN CHANCES SHIFTING SOUTH ON FRIDAY
ALONG WITH POSITION OF BOUNDARY...ALTHOUGH ITS HARD TO TELL THIS FAR
OUT IN TIME HOW MUCH DRYING OCCURS OVER NRN ZONES. WITH AN
ADDITIONAL SHIFT OF EVERYTHING TO THE SOUTH THANKS TO THE DEEPENING
UPPER TROUGH OFF THE NE COAST SATURDAY MAY BE DRY FOR ALL BUT
SOUTHERNMOST AREAS. THIS SETUP LASTS INTO SUNDAY...GENERALLY
RAIN-FREE CONDITIONS WITH TEMPERATURES A LITTLE BELOW CLIMO. HIGH
BUILDS OVERHEAD ON MONDAY WHICH SHOULD FAVOR A RETURN OF TEMPS NEAR
NORMAL IF NOT A TAD HIGHER.
&&
.AVIATION /12Z TUESDAY THROUGH SATURDAY/...
AS OF 12Z...ATMOSPHERE WILL CONTINUE TO MOISTEN UP OVER THE NEXT 24
HOURS WITH PRECIPITABLE WATER VALUES EXPECTED TO RISE FROM ABOUT 1.3
INCHES TO AROUND 1.7 INCHES BY THE END OF THE FORECAST PERIOD. HIGH
PRESSURE WILL CONTINUE TO RECEDE WITH A WEAK THERMAL TROUGH EXPECTED
THIS AFTERNOON. GUSTY SOUTHWEST WINDS WILL CONTINUE TO TRANSPORT
MOISTURE. SCATTERED CONVECTION IS EXPECTED TO DEVELOP BY EARLY
AFTERNOON. THE COASTAL TERMINALS COULD SEE SOME CONVECTION
EARLY...BUT THE SEA BREEZE BOUNDARY SHOULD KEEP THE ACTIVITY WEST OF
THE TERMINALS BY 20Z. INLAND TERMINALS WILL HAVE CONVECTION ON OR
NEARBY THE AREA THROUGH EARLY EVENING...DIMINISHING DIURNALLY BY
02Z. SOUTHWEST FLOW OVERNIGHT WILL LIKELY BE TOO STRONG TO SUPPORT
FOG.
EXTENDED OUTLOOK...SCATTERED SHOWERS/TSTMS EXPECTED WEDNESDAY
THROUGH FRIDAY...MAINLY IN THE AFTN HOURS...WITH BRIEF AND ISOLATED
PERIODS OF SUB-VFR CONDITIONS POSSIBLE. SATURDAY WILL BE DRIER AS A
COLD FRONT FINALLY DROPS SOUTHWARD INTO THE CAROLINAS.
&&
.MARINE...
NEAR TERM /THROUGH TONIGHT/...
AS OF 3 AM TUESDAY...HIGH PRESSURE OVER BERMUDA WILL EXTEND A RIDGE
AXIS WESTWARD ALONG 30 DEGREES NORTH LATITUDE TODAY. A PIEDMONT
TROUGH OVER THE INTERIOR CAROLINAS WILL HELP COMPRESS THE PRESSURE
GRADIENT WITH SUSTAINED WINDS AVERAGING 15 KNOTS. ADD TO THAT
THE AFTERNOON SEABREEZE AND WE COULD SEE WINDS NEARSHORE INCREASE TO
20 KNOTS DURING THE AFTERNOON AND EARLY EVENING HOURS. MARINE MOS
GUIDANCE BASED OFF THE GFS EVEN HAS 24 KNOTS AT WRIGHTSVILLE BEACH
AT 21Z THIS AFTERNOON. WHILE MY FORECAST IS NOT QUITE THAT STRONG...
IT STILL SHOULD BECOME QUITE BREEZY AT THE BEACHES AND ACROSS THE
NEARSHORE WATERS THIS AFTERNOON.
ISOLATED SHOWERS AND THUNDERSTORMS WILL BECOME POSSIBLE THIS
AFTERNOON. ALTHOUGH LOW-LEVEL WINDS WILL BE ONSHORE THROUGH THE
DAY...WINDS UP AT CLOUD LEVEL WILL BE FROM THE WEST PUSHING ANY
POTENTIAL SHOWERS/T-STORMS EASTWARD. SEAS CURRENTLY 2-3 FEET SHOULD
BUILD TO 3-4 FEET BY LATE IN THE DAY.
SHORT TERM /WEDNESDAY THROUGH THURSDAY NIGHT/...
AS OF 3 AM TUESDAY...A BIT OF A PREFRONTAL FLOW REGIME IN PLACE ON
WEDNESDAY. MORE ACCURATE TO SAY THAT SW WINDS THE RESULT OF PIEDMONT
TROUGH SINCE THE ACTUAL BACKDOOR FRONT WILL BE WELL TO THE NORTH. IT
WILL DROP INTO THE REGION ON THURSDAY HOWEVER AND BE QUITE SLOW TO
MAKE ITS WAY SOUTHWARD. JUST AHEAD OF THE FRONT WINDS WILL TEND TO
GO LIGHT AND VARIABLE. THEN A N TO NE FLOW WILL SPREAD SOUTHWARD
ACROSS THE MARINE ZONES.
LONG TERM /FRIDAY THROUGH SATURDAY/...
AS OF 3 AM TUESDAY...COASTAL ZONES MAY END UP BISECTED NORTH TO
SOUTH BY A BACK DOOR COLD FRONT FOR MUCH OF FRIDAY. A LIGHT NE WIND
WILL THUS SPREAD ACROSS NORTHERN ZONES WITH SOUTHWESTERLY WIND OVER
SOUTHERN ZONES AND AN AREA OF LIGHT AND VARIABLE WINDS BETWEEN. SEAS
THUS REMAIN QUITE TAME...GENERALLY JUST 2 FT OR LESS. HIGHER WINDS
AND SEAS WILL BECOME ESTABLISHED ON SATURDAY AS THE BOUNDARY SINKS
FURTHER TO THE SOUTH AND HIGH PRESSURE MANAGES TO BUILD IN FROM THE
NORTH. A NE GRADIENT WILL TIGHTEN LEADING TO THE DETERIORATED
CONDITIONS BUT NO ADVISORY OR EVEN HEADLINES EXPECTED.
&&
.ILM WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
NC...NONE.
MARINE...NONE.
&&
$$
NEAR TERM...TRA
SHORT TERM...MBB
LONG TERM...MBB
AVIATION...43
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
330 AM EDT TUE MAY 27 2014
.SYNOPSIS...
WARM AND HUMID WEATHER IS EXPECTED OVER THE NEXT SEVERAL DAYS
WHICH MAY GIVE RISE TO SCATTERED MAINLY AFTERNOON THUNDERSTORMS. A
BACK DOOR COLD FRONT WILL SLOWLY SINK SOUTH ACROSS THE AREA
THURSDAY INTO FRIDAY. HIGH PRESSURE THEN BUILDS IN FROM THE NORTH
OVER THE WEEKEND KEEPING THE AREA RAIN FREE.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 3 AM TUESDAY...A NARROW UPPER LEVEL RIDGE EXTENDING FROM THE
SOUTHERN APPALACHIANS TO THE FLORIDA PANHANDLE WILL DEAMPLIFY TODAY
AS IT MOVES EAST TOWARD THE COAST THIS EVENING. IN THE LOW LEVELS
BERMUDA HIGH PRESSURE WILL EXTEND A RIDGE AXIS WESTWARD ACROSS
NORTHERN FLORIDA WHILE A PIEDMONT TROUGH DEVELOPS ACROSS THE
INTERIOR CAROLINAS. A WEAK UPPER DISTURBANCE CURRENTLY JUST WEST OF
INTERSTATE 95 HAS BEEN PRODUCING ISOLATED SHOWERS ACROSS THE
PIEDMONT EARLY THIS MORNING. AS THIS DISTURBANCE MAKES IT WAY
EASTWARD TO THE COAST BY LATE MORNING CLOUDS WILL INCREASE ALTHOUGH
PRECIP CHANCES APPEAR QUITE SMALL.
THE POTENTIAL FOR MORE WIDESPREAD SURFACE-BASED CONVECTION WILL
DEVELOP THIS AFTERNOON AS SURFACE-BASED CAPE INCREASES TO 1500 J/KG.
ALTHOUGH THIS MORNING`S WEAK UPPER DISTURBANCE WILL BE OFFSHORE BY
AFTERNOON...A DIFFERENTIAL HEATING BOUNDARY ALONG THE PIEDMONT/
SANDHILLS INTERFACE PLUS THE SEABREEZE COULD INITIATE NEW SHOWERS
AND STORMS IN THIS UNSTABLE AIRMASS. THE NAM IS MUCH MORE AGGRESSIVE
WITH THIS POTENTIAL THAN THE GFS...WITH THE HRRR AND RUC IN THE
MIDDLE. MY FORECAST POPS ARE AROUND 30 PERCENT...BUT A LITTLE LOWER
IN THE WILMINGTON AREA WHERE PRECIPITABLE WATER VALUES WILL REMAIN
LOWEST. HIGH TEMPERATURES SHOULD REACH THE MID TO UPPER 80S...EXCEPT
AROUND 90 IN THE DARLINGTON-BENNETTSVILLE AREA.
AFTERNOON CONVECTION SHOULD DIE AWAY QUICKLY THIS EVENING...ALTHOUGH
CLOUD COVER MAY REMAIN A BIT MORE EXTENSIVE OVERNIGHT THAN WE HAVE
SEEN THE PAST SEVERAL NIGHTS GIVEN THE INCREASE IN MID-LEVEL
MOISTURE AHEAD OF AN UPPER LEVEL LOW OVER THE WESTERN GULF COAST.
LOWS SHOULD FALL INTO THE UPPER 60S INLAND TO NEAR 70 ON THE COAST.
&&
.SHORT TERM /WEDNESDAY THROUGH THURSDAY NIGHT/...
AS OF 3 AM TUESDAY...WEDNESDAY FINDS AN UPPER TROUGH SLOWLY
PROGRESSING EAST ACROSS THE GULF STATES. AHEAD OF THIS FEATURE A
SHORTWAVE RIDGE WILL REMAIN POKED UP OVER THE CAROLINAS. THE RIDGE
WILL NOT BE SUFFICIENTLY STRONG TO CAP OFF ALL CONVECTION ACROSS THE
REGION BUT COVERAGE MAY BE AT A RELATIVE MINIMUM COMPARED TO OTHER
DAYS OF THE FCST. PIEDMONT TROUGH TO OUR WEST MORE A FOCUS ACCORDING
TO WRF WHEREAS GFS SEEMS TO LIKE GFS BETTER. GIVEN THAT STORM
MOTION WILL HAVE A GOOD EASTERLY COMPONENT FEEL THAT THE MOS POPS
GENERALLY AROUND 40 WILL SUFFICE AREA-WIDE. TEMPERATURES WILL BE A
FEW DEGREES ABOVE CLIMO WITH MOST PLACES WITHIN A FEW DEGREES OF 90.
A BACKDOOR COLD FRONT WILL SLOWLY SAG SOUTHWARD ACROSS THE REGION ON
THURSDAY. THIS WILL BE THE MAIN FOCUS FOR CONVECTION AND SO PICKING
OUT FAVORED AREAS WILL DEPEND ON THE SPEED/LOCATION OF THE BOUNDARY
SINCE PLACES SHOULD TEND TO STABILIZE TO ITS NORTH.
&&
.LONG TERM /FRIDAY THROUGH MONDAY/...
AS OF 3 AM TUESDAY...MAIN RAIN CHANCES SHIFTING SOUTH ON FRIDAY
ALONG WITH POSITION OF BOUNDARY...ALTHOUGH ITS HARD TO TELL THIS FAR
OUT IN TIME HOW MUCH DRYING OCCURS OVER NRN ZONES. WITH AN
ADDITIONAL SHIFT OF EVERYTHING TO THE SOUTH THANKS TO THE DEEPENING
UPPER TROUGH OFF THE NE COAST SATURDAY MAY BE DRY FOR ALL BUT
SOUTHERNMOST AREAS. THIS SETUP LASTS INTO SUNDAY...GENERALLY
RAIN-FREE CONDITIONS WITH TEMPERATURES A LITTLE BELOW CLIMO. HIGH
BUILDS OVERHEAD ON MONDAY WHICH SHOULD FAVOR A RETURN OF TEMPS NEAR
NORMAL IF NOT A TAD HIGHER.
&&
.AVIATION /06Z TUESDAY THROUGH SATURDAY/...
AS OF 06Z...EXPECT VFR TO PREVAIL OVERNIGHT WITH SOUTHWEST WINDS 5-8
KTS. HAVE REMOVED MENTION OF MVFR VSBYS AT KFLO/KLBT AS IT APPEARS
SFC WINDS WILL REMAIN AROUND 5 KTS THROUGH DAYBREAK...AND FOG SEEMS
UNLIKELY. INCREASING MOISTURE DURING THE DAY WILL HELP FUEL
SCATTERED SHOWERS AND TSTMS THROUGH THE AFTERNOON. INLAND SFC TROUGH
WILL LIKELY BE THE MAIN FOCUS FOR CONVECTION...SO WILL INCLUDE VCTS
FOR KFLO/KLBT AFTER MIDDAY. THIS IS WHERE THE GREATEST INSTABILITY
IS EXPECTED TO DEVELOP WITH DAYTIME HEATING. WE COULD ALSO SEE SOME
SHOWER ACTIVITY ALONG THE SEA BREEZE...WHICH WARRANTS VCSH FOR
KMYR/KCRE/KILM AFTER 18Z. WEAK WESTERLY STEERING FLOW ALOFT WILL
PUSH INLAND ACTIVITY TOWARD THE COAST LATER IN THE DAY...SO THE
COASTAL TERMS COULD SEE PCPN EVEN AFTER 00Z WEDNESDAY. VFR WILL
PREVAIL TODAY...BUT BRIEF AND LOCALIZED PERIODS OF MVFR/IFR VSBYS
ARE POSSIBLE IN STORMS. THE WINDS WILL BE SOUTHWEST 10-15 KTS WITH
GUSTS OF 20 KTS AT THE COASTAL SITES BY THE AFTERNOON.
EXTENDED OUTLOOK...SCATTERED SHOWERS/TSTMS EXPECTED WEDNESDAY
THROUGH FRIDAY...MAINLY IN THE AFTN HOURS...WITH BRIEF AND ISOLATED
PERIODS OF SUB-VFR CONDITIONS POSSIBLE. SATURDAY WILL BE DRIER AS A
COLD FRONT FINALLY DROPS SOUTHWARD INTO THE CAROLINAS.
&&
.MARINE...
NEAR TERM /THROUGH TONIGHT/...
AS OF 3 AM TUESDAY...HIGH PRESSURE OVER BERMUDA WILL EXTEND A RIDGE
AXIS WESTWARD ALONG 30 DEGREES NORTH LATITUDE TODAY. A PIEDMONT
TROUGH OVER THE INTERIOR CAROLINAS WILL HELP COMPRESS THE PRESSURE
GRADIENT WITH SUSTAINED WINDS AVERAGING 15 KNOTS. ADD TO THAT
THE AFTERNOON SEABREEZE AND WE COULD SEE WINDS NEARSHORE INCREASE TO
20 KNOTS DURING THE AFTERNOON AND EARLY EVENING HOURS. MARINE MOS
GUIDANCE BASED OFF THE GFS EVEN HAS 24 KNOTS AT WRIGHTSVILLE BEACH
AT 21Z THIS AFTERNOON. WHILE MY FORECAST IS NOT QUITE THAT STRONG...
IT STILL SHOULD BECOME QUITE BREEZY AT THE BEACHES AND ACROSS THE
NEARSHORE WATERS THIS AFTERNOON.
ISOLATED SHOWERS AND THUNDERSTORMS WILL BECOME POSSIBLE THIS
AFTERNOON. ALTHOUGH LOW-LEVEL WINDS WILL BE ONSHORE THROUGH THE
DAY...WINDS UP AT CLOUD LEVEL WILL BE FROM THE WEST PUSHING ANY
POTENTIAL SHOWERS/T-STORMS EASTWARD. SEAS CURRENTLY 2-3 FEET SHOULD
BUILD TO 3-4 FEET BY LATE IN THE DAY.
SHORT TERM /WEDNESDAY THROUGH THURSDAY NIGHT/...
AS OF 3 AM TUESDAY...A BIT OF A PREFRONTAL FLOW REGIME IN PLACE ON
WEDNESDAY. MORE ACCURATE TO SAY THAT SW WINDS THE RESULT OF PIEDMONT
TROUGH SINCE THE ACTUAL BACKDOOR FRONT WILL BE WELL TO THE NORTH. IT
WILL DROP INTO THE REGION ON THURSDAY HOWEVER AND BE QUITE SLOW TO
MAKE ITS WAY SOUTHWARD. JUST AHEAD OF THE FRONT WINDS WILL TEND TO
GO LIGHT AND VARIABLE. THEN A N TO NE FLOW WILL SPREAD SOUTHWARD
ACROSS THE MARINE ZONES.
LONG TERM /FRIDAY THROUGH SATURDAY/...
AS OF 3 AM TUESDAY...COASTAL ZONES MAY END UP BISECTED NORTH TO
SOUTH BY A BACK DOOR COLD FRONT FOR MUCH OF FRIDAY. A LIGHT NE WIND
WILL THUS SPREAD ACROSS NORTHERN ZONES WITH SOUTHWESTERLY WIND OVER
SOUTHERN ZONES AND AN AREA OF LIGHT AND VARIABLE WINDS BETWEEN. SEAS
THUS REMAIN QUITE TAME...GENERALLY JUST 2 FT OR LESS. HIGHER WINDS
AND SEAS WILL BECOME ESTABLISHED ON SATURDAY AS THE BOUNDARY SINKS
FURTHER TO THE SOUTH AND HIGH PRESSURE MANAGES TO BUILD IN FROM THE
NORTH. A NE GRADIENT WILL TIGHTEN LEADING TO THE DETERIORATED
CONDITIONS BUT NO ADVISORY OR EVEN HEADLINES EXPECTED.
&&
.ILM WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
NC...NONE.
MARINE...NONE.
&&
$$
NEAR TERM...TRA
SHORT TERM...MBB
LONG TERM...MBB
AVIATION...BJR
AREA FORECAST DISCUSSION
NWS BISMARCK ND
1003 PM CDT WED MAY 28 2014
.UPDATE...
ISSUED AT 1002 CDT WED MAY 28 2014
QUICK UPDATE AGAIN TO BETTER REFLECT LIGHT RAIN ACROSS FAR
WEST...WHERE POPS WERE TOO LOW. MAINTAINED CONVECTIVE CHANCES AS
PREVIOUSLY SHOWN AND CONTINUING TO WATCH CONVECTION IN EAST
CENTRAL MT WHICH HAS STRENGTHENED IN PAST HALF HOUR.
UPDATE ISSUED AT 943 PM CDT WED MAY 28 2014
MAIN CHANGES WERE ADJUSTMENTS TO POPS. AS MENTIONED IN SPC MCD
ISSUED A FEW MINUTES AGO CONVECTION ACROSS EAST CENTRAL MONTANA IS
LESS ORGANIZED THAN THE CLUSTER OF STORMS ACROSS NORTH CENTRAL
MONTANA. HI RES MODELS CONTINUE TO HAVE CHALLENGES WITH ONGOING
CONVECTION. HRRR INITIALIZED WELL WITH 01Z RUN...BUT APPEARS TO
OVERDUE EXPANSION OF CONVECTION IN SUBSEQUENT HOURS. RAP TIMING
APPEARS TO BE SLOWER AND MORE ACCURATE. BOTH MODELS HINT AT
STRONGER CLUSTER IN NORTH CENTRAL MONTANA MOVING NORTHEAST INTO
CANADA. GIVEN THESE TRENDS...HAVE LOWERED POPS NEXT COUPLE HOURS
AND MAINTAINED BEST CHANCE ACROSS NORTHWEST ND. DID INTRODUCE SOME
POPS ACROSS SOUTHWEST BASED ON WEAK RETURNS APPROACHING ON BOWMAN
RADAR.
UPDATE ISSUED AT 713 PM CDT WED MAY 28 2014
MAIN UPDATE CONCERN IS CONVECTIVE POTENTIAL TONIGHT. CURRENTLY
MOST OF MONTANA IS IN A SEVERE THUNDERSTORM WATCH. RADAR MOSAIC
SHOWS THUNDERSTORMS STILL WELL WEST OF NORTH DAKOTA. ATMOSPHERE
STILL WELL CAPPED AND HI-RES MODELS /RAP AND HRRR/ ARE TOO FAR
EAST WITH CONVECTION COMPARED TO CURRENT RADAR. HAVE TRIMMED BACK
POPS FOR EARLY EVENING AND WILL CONTINUE TO MONITOR TRENDS FOR
NEXT UPDATE. LATEST BUFR SOUNDINGS FOR KISN ALSO SHOW SUBSTANTIAL
CAP IN PLACE THROUGH THE EVENING. 18Z NAM KEEPS CWA DRY OVERNIGHT
WHILE GFS SPREADS SOME SHOWERS/THUNDERSTORMS INTO THE WEST BY 06Z.
ALSO UPDATED HOURLY GRIDS TO ACCOUNT FOR LESS CLOUD COVER AND
SLIGHT TEMP ADJUSTMENTS FOR WEST WHICH WAS RUNNING SLIGHTLY COOLER
THAN NORMAL AND THE EAST WHICH WAS A LITTLE WARMER THAN CURRENT
FORECAST.
&&
.SHORT TERM...(THIS AFTERNOON THROUGH THURSDAY)
ISSUED AT 321 PM CDT WED MAY 28 2014
THE MAIN CHALLENGE FOR THE PERIOD WILL BE DETERMINING THE SEVERE
POTENTIAL OVER EXTREME NORTHWESTERN NORTH DAKOTA TONIGHT...AND AGAIN
OVER WESTERN AND NORTH CENTRAL NORTH DAKOTA LATE THURSDAY AFTERNOON.
MSAS ANALYSIS INDICATES A SURFACE LOW DEEPENING OVER CENTRAL MONTANA
THIS AFTERNOON...WHICH IS SERVING TO INCREASE THE LOW-LEVEL JET
OVER WESTERN NORTH DAKOTA. THE INCREASING LOW-LEVEL MOISTURE FEED IS
INCREASING SURFACE-BASED CAPE OVER SOUTHWESTERN NORTH DAKOTA/EASTERN
MONTANA THIS AFTERNOON. HOWEVER...CONVECTION IS HAVING A DIFFICULT
TIME INITIATING AS MUCH COOLER BOUNDARY LAYER TEMPERATURES IN THE WAKE
OF AN MCV HAS GENERATED VERY WEAK LOW-LEVEL LAPSE RATES (0-3 KM
LAPSE RATES AROUND 6 C/KM OVER WESTERN NORTH DAKOTA PER SPC
ANALYSIS). RAPID DESTABILIZATION WILL NEED TO OCCUR TO GET
CONVECTION TO DEVELOP ALONG THE SURFACE TROUGH SETTING UP OVER
CENTRAL MONTANA LATER THIS AFTERNOON AND EARLY EVENING. FURTHER
COMPLICATING THE CONVECTIVE POTENTIAL IS A STRENGTHENING CAP OVER
WESTERN NORTH DAKOTA AHEAD OF THE DEEPENING LOW. MODELS CONTINUE TO
PROG CIN GREATER THAN 500 J/KG DEVELOPING OVER WESTERN NORTH DAKOTA
AFTER SUNSET AND CONTINUING OVERNIGHT. WITH THAT BEING SAID...THE
GREATEST DYNAMICS/SURFACE FORCING IS PROGGED TO SET UP OVER SOUTH
CENTRAL SASKATCHEWAN EARLY THIS EVENING. IF SAID CONVECTION
DEVELOPS...IT COULD DEVELOP ITS OWN COLD POOL AND ADVECT INTO THE
EXTREME NORTHWESTERN PORTIONS OF NORTH DAKOTA. AS A
RESULT...INCLUDED A SEVERE MENTION IN THE FORECAST FOR THE
NORTHWESTERN COUNTIES BETWEEN 00Z-06Z TONIGHT...CONSISTENT WITH
SPC`S DAY 1 OUTLOOK. THE MAIN THREATS WILL BE LARGE HAIL AND
DAMAGING WINDS. ISOLATED TORNADOES WILL ALSO BE POSSIBLE.
THIS ACTIVITY IS PROGGED TO WANE AFTER MIDNIGHT AS THE BOUNDARY
LAYER STABILIZES. DRY CONDITIONS ARE FORECAST TO CONTINUE AREAWIDE
THROUGH LATE THURSDAY MORNING.
BY THURSDAY AFTERNOON...A SURFACE TROUGH IS PROGGED TO STALL ACROSS
WESTERN NORTH DAKOTA. ENHANCED SURFACE MOISTURE CONVERGENCE ALONG
THE BOUNDARY COMBINED WITH MUCAPE VALUES BETWEEN 1500-2000
J/KG...AND 0-6KM SHEAR AROUND 35 KNOTS WILL LIKELY PRODUCE A LINE OF
THUNDERSTORMS EXTENDING FROM NORTH CENTRAL NORTH DAKOTA INTO
SOUTHWESTERN NORTH DAKOTA. THIS LINE COULD DEVELOP INTO A SQUALL
LINE WITH HEAVY RAINFALL AND DAMAGING WINDS BEING THE PRIMARY
THREATS. WILL HIGHLIGHT THIS POTENTIAL IN THE HWO FOR NOW.
.LONG TERM...(THURSDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 321 PM CDT WED MAY 28 2014
VERY ACTIVE WEATHER PATTERN THROUGH EARLY NEXT WEEK.
FORECAST HIGHLIGHTS IN THE LONG TERM PERIOD WILL BE CHANCES FOR
STRONG TO SEVERE THUNDERSTORMS AND VERY HEAVY RAINFALL THURSDAY
NIGHT THROUGH FRIDAY NIGHT...CONTINUED CHANCES FOR HEAVY RAIN OVER
THE WEEKEND AND INTO EARLY PORTIONS OF NEXT WEEK...ALONG WITH
COOLER TEMPERATURES OVER MUCH OF THE PERIOD.
SFC TROUGH MOVES SLOWLY EAST ACROSS WESTERN INTO CENTRAL NORTH
DAKOTA THURSDAY NIGHT...AND WILL BE THE FOCUS FOR DIURNALLY
DRIVEN THUNDERSTORMS...SOME POTENTIALLY SEVERE GIVEN THE
INSTABILITY AND FORCING ADVERTISED. MODELS STILL PORTRAY STRONG
MOISTURE TRANSPORT AHEAD OF THE SFC TROUGH POOLING ALONG THE
BOUNDARY...INCREASING THE POTENTIAL FOR HEAVY RAIN. PW VALUES ARE
PROJECTED TO NEAR THE 99TH PERCENTILE SO PLENTY OF MOISTURE TO
WORK WITH GENERATING WIDESPREAD 1-2 INCH RAINFALL. LOCALLY HIGHER
AMOUNTS WITH HEAVIER THUNDERSTORMS WILL BE VERY LIKELY. SFC TROUGH
SLOWLY MOVES EAST FRIDAY...BECOMING QUASI-STATIONARY OVER THE
SOUTH CENTRAL EAST INTO THE JAMES AND RED RIVER VALLEY REGIONS.
THUS ANOTHER ROUND OF STRONG TO SEVERE STORMS WITH HEAVY RAIN
LIKELY ALONG TO AHEAD OF THE SFC BOUNDARY. WILL MAINTAIN A DRY
FORECAST ACROSS THE NORTHWEST QUARTER OF ND FRIDAY WITH HIGH
PRESSURE AND A STABLE AIRMASS DEVELOPING SOUTH AND EAST FROM
CANADA IN THE WAKE OF THE TROUGH.
COOLER TEMPERATURES AND MORE STABLE CONDITIONS ARE STILL FORECAST
BY BOTH THE 12Z GFS/ECMWF SATURDAY THROUGH MONDAY WITH A COOL
NORTHEAST/EASTERLY FLOW DEVELOPING WITH HIGH PRESSURE OVER SOUTH
CENTRAL CANADA AND SURFACE LOW PRESSURE DEVELOPING FROM THE HIGH
PLAINS OF WYOMING EASTERLY INTO NEBRASKA/SOUTH DAKOTA. IDEAL
PLACEMENT FOR STRONG OVERRUNNING FLOW ACROSS NORTH
DAKOTA...SETTING US UP FOR A PROLONGED PERIOD OF MODERATE TO HEAVY
PRECIPITATION. WHILE THE MORE STABLE CONDITIONS RESULTS IN MINIMAL
CHANCES FOR SEVERE WEATHER...SOME GUIDANCE DOES TRY TO CREEP
MARGINAL INSTABILITY ACROSS MY FAR SOUTH SO WILL NOT COMPLETELY
RULE THIS OUT. HEAVY RAIN WILL BE THE MAIN IMPACT.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z THURSDAY EVENING)
ISSUED AT 713 PM CDT WED MAY 28 2014
EXPECT BREEZY/WINDY SOUTHEASTERLY WINDS DEVELOPING OVERNIGHT AND
THURSDAY AS A STORM SYSTEM TRACKS FROM MONTANA NORTHEASTWARD TO
CANADA. SOME SHOWERS/THUNDERSTORMS ARE POSSIBLE ACROSS THE WEST
/KISN/ OVERNIGHT. THE ASSOCIATED COLD FRONT SLOWLY MOVES INTO THE
STATE BY THURSDAY AFTERNOON WITH WINDS SHIFTING TO THE
WEST/NORTHWEST BEHIND IT. SHOWERS/THUNDERSTORMS ARE EXPECTED TO
DEVELOP ALONG THIS FRONT POSSIBLY AFFECTING KISN/KDIK LATE
AFTERNOON. NOT ENOUGH CONFIDENCE IN TIMING OR PLACEMENT TO MENTION
IN THE TAFS YET...ESPECIALLY SINCE PRECIP MAY OCCUR AFTER 00Z FRI.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...JNS
SHORT TERM...TM
LONG TERM...NH
AVIATION...JNS
AREA FORECAST DISCUSSION
NWS BISMARCK ND
943 PM CDT WED MAY 28 2014
.UPDATE...
ISSUED AT 943 PM CDT WED MAY 28 2014
MAIN CHANGES WERE ADJUSTMENTS TO POPS. AS MENTIONED IN SPC MCD
ISSUED A FEW MINUTES AGO CONVECTION ACROSS EAST CENTRAL MONTANA IS
LESS ORGANIZED THAN THE CLUSTER OF STORMS ACROSS NORTH CENTRAL
MONTANA. HI RES MODELS CONTINUE TO HAVE CHALLENGES WITH ONGOING
CONVECTION. HRRR INITIALIZED WELL WITH 01Z RUN...BUT APPEARS TO
OVERDUE EXPANSION OF CONVECTION IN SUBSEQUENT HOURS. RAP TIMING
APPEARS TO BE SLOWER AND MORE ACCURATE. BOTH MODELS HINT AT
STRONGER CLUSTER IN NORTH CENTRAL MONTANA MOVING NORTHEAST INTO
CANADA. GIVEN THESE TRENDS...HAVE LOWERED POPS NEXT COUPLE HOURS
AND MAINTAINED BEST CHANCE ACROSS NORTHWEST ND. DID INTRODUCE SOME
POPS ACROSS SOUTHWEST BASED ON WEAK RETURNS APPROACHING ON BOWMAN
RADAR.
UPDATE ISSUED AT 713 PM CDT WED MAY 28 2014
MAIN UPDATE CONCERN IS CONVECTIVE POTENTIAL TONIGHT. CURRENTLY
MOST OF MONTANA IS IN A SEVERE THUNDERSTORM WATCH. RADAR MOSAIC
SHOWS THUNDERSTORMS STILL WELL WEST OF NORTH DAKOTA. ATMOSPHERE
STILL WELL CAPPED AND HI-RES MODELS /RAP AND HRRR/ ARE TOO FAR
EAST WITH CONVECTION COMPARED TO CURRENT RADAR. HAVE TRIMMED BACK
POPS FOR EARLY EVENING AND WILL CONTINUE TO MONITOR TRENDS FOR
NEXT UPDATE. LATEST BUFR SOUNDINGS FOR KISN ALSO SHOW SUBSTANTIAL
CAP IN PLACE THROUGH THE EVENING. 18Z NAM KEEPS CWA DRY OVERNIGHT
WHILE GFS SPREADS SOME SHOWERS/THUNDERSTORMS INTO THE WEST BY 06Z.
ALSO UPDATED HOURLY GRIDS TO ACCOUNT FOR LESS CLOUD COVER AND
SLIGHT TEMP ADJUSTMENTS FOR WEST WHICH WAS RUNNING SLIGHTLY COOLER
THAN NORMAL AND THE EAST WHICH WAS A LITTLE WARMER THAN CURRENT
FORECAST.
&&
.SHORT TERM...(THIS AFTERNOON THROUGH THURSDAY)
ISSUED AT 321 PM CDT WED MAY 28 2014
THE MAIN CHALLENGE FOR THE PERIOD WILL BE DETERMINING THE SEVERE
POTENTIAL OVER EXTREME NORTHWESTERN NORTH DAKOTA TONIGHT...AND AGAIN
OVER WESTERN AND NORTH CENTRAL NORTH DAKOTA LATE THURSDAY AFTERNOON.
MSAS ANALYSIS INDICATES A SURFACE LOW DEEPENING OVER CENTRAL MONTANA
THIS AFTERNOON...WHICH IS SERVING TO INCREASE THE LOW-LEVEL JET
OVER WESTERN NORTH DAKOTA. THE INCREASING LOW-LEVEL MOISTURE FEED IS
INCREASING SURFACE-BASED CAPE OVER SOUTHWESTERN NORTH DAKOTA/EASTERN
MONTANA THIS AFTERNOON. HOWEVER...CONVECTION IS HAVING A DIFFICULT
TIME INITIATING AS MUCH COOLER BOUNDARY LAYER TEMPERATURES IN THE WAKE
OF AN MCV HAS GENERATED VERY WEAK LOW-LEVEL LAPSE RATES (0-3 KM
LAPSE RATES AROUND 6 C/KM OVER WESTERN NORTH DAKOTA PER SPC
ANALYSIS). RAPID DESTABILIZATION WILL NEED TO OCCUR TO GET
CONVECTION TO DEVELOP ALONG THE SURFACE TROUGH SETTING UP OVER
CENTRAL MONTANA LATER THIS AFTERNOON AND EARLY EVENING. FURTHER
COMPLICATING THE CONVECTIVE POTENTIAL IS A STRENGTHENING CAP OVER
WESTERN NORTH DAKOTA AHEAD OF THE DEEPENING LOW. MODELS CONTINUE TO
PROG CIN GREATER THAN 500 J/KG DEVELOPING OVER WESTERN NORTH DAKOTA
AFTER SUNSET AND CONTINUING OVERNIGHT. WITH THAT BEING SAID...THE
GREATEST DYNAMICS/SURFACE FORCING IS PROGGED TO SET UP OVER SOUTH
CENTRAL SASKATCHEWAN EARLY THIS EVENING. IF SAID CONVECTION
DEVELOPS...IT COULD DEVELOP ITS OWN COLD POOL AND ADVECT INTO THE
EXTREME NORTHWESTERN PORTIONS OF NORTH DAKOTA. AS A
RESULT...INCLUDED A SEVERE MENTION IN THE FORECAST FOR THE
NORTHWESTERN COUNTIES BETWEEN 00Z-06Z TONIGHT...CONSISTENT WITH
SPC`S DAY 1 OUTLOOK. THE MAIN THREATS WILL BE LARGE HAIL AND
DAMAGING WINDS. ISOLATED TORNADOES WILL ALSO BE POSSIBLE.
THIS ACTIVITY IS PROGGED TO WANE AFTER MIDNIGHT AS THE BOUNDARY
LAYER STABILIZES. DRY CONDITIONS ARE FORECAST TO CONTINUE AREAWIDE
THROUGH LATE THURSDAY MORNING.
BY THURSDAY AFTERNOON...A SURFACE TROUGH IS PROGGED TO STALL ACROSS
WESTERN NORTH DAKOTA. ENHANCED SURFACE MOISTURE CONVERGENCE ALONG
THE BOUNDARY COMBINED WITH MUCAPE VALUES BETWEEN 1500-2000
J/KG...AND 0-6KM SHEAR AROUND 35 KNOTS WILL LIKELY PRODUCE A LINE OF
THUNDERSTORMS EXTENDING FROM NORTH CENTRAL NORTH DAKOTA INTO
SOUTHWESTERN NORTH DAKOTA. THIS LINE COULD DEVELOP INTO A SQUALL
LINE WITH HEAVY RAINFALL AND DAMAGING WINDS BEING THE PRIMARY
THREATS. WILL HIGHLIGHT THIS POTENTIAL IN THE HWO FOR NOW.
.LONG TERM...(THURSDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 321 PM CDT WED MAY 28 2014
VERY ACTIVE WEATHER PATTERN THROUGH EARLY NEXT WEEK.
FORECAST HIGHLIGHTS IN THE LONG TERM PERIOD WILL BE CHANCES FOR
STRONG TO SEVERE THUNDERSTORMS AND VERY HEAVY RAINFALL THURSDAY
NIGHT THROUGH FRIDAY NIGHT...CONTINUED CHANCES FOR HEAVY RAIN OVER
THE WEEKEND AND INTO EARLY PORTIONS OF NEXT WEEK...ALONG WITH
COOLER TEMPERATURES OVER MUCH OF THE PERIOD.
SFC TROUGH MOVES SLOWLY EAST ACROSS WESTERN INTO CENTRAL NORTH
DAKOTA THURSDAY NIGHT...AND WILL BE THE FOCUS FOR DIURNALLY
DRIVEN THUNDERSTORMS...SOME POTENTIALLY SEVERE GIVEN THE
INSTABILITY AND FORCING ADVERTISED. MODELS STILL PORTRAY STRONG
MOISTURE TRANSPORT AHEAD OF THE SFC TROUGH POOLING ALONG THE
BOUNDARY...INCREASING THE POTENTIAL FOR HEAVY RAIN. PW VALUES ARE
PROJECTED TO NEAR THE 99TH PERCENTILE SO PLENTY OF MOISTURE TO
WORK WITH GENERATING WIDESPREAD 1-2 INCH RAINFALL. LOCALLY HIGHER
AMOUNTS WITH HEAVIER THUNDERSTORMS WILL BE VERY LIKELY. SFC TROUGH
SLOWLY MOVES EAST FRIDAY...BECOMING QUASI-STATIONARY OVER THE
SOUTH CENTRAL EAST INTO THE JAMES AND RED RIVER VALLEY REGIONS.
THUS ANOTHER ROUND OF STRONG TO SEVERE STORMS WITH HEAVY RAIN
LIKELY ALONG TO AHEAD OF THE SFC BOUNDARY. WILL MAINTAIN A DRY
FORECAST ACROSS THE NORTHWEST QUARTER OF ND FRIDAY WITH HIGH
PRESSURE AND A STABLE AIRMASS DEVELOPING SOUTH AND EAST FROM
CANADA IN THE WAKE OF THE TROUGH.
COOLER TEMPERATURES AND MORE STABLE CONDITIONS ARE STILL FORECAST
BY BOTH THE 12Z GFS/ECMWF SATURDAY THROUGH MONDAY WITH A COOL
NORTHEAST/EASTERLY FLOW DEVELOPING WITH HIGH PRESSURE OVER SOUTH
CENTRAL CANADA AND SURFACE LOW PRESSURE DEVELOPING FROM THE HIGH
PLAINS OF WYOMING EASTERLY INTO NEBRASKA/SOUTH DAKOTA. IDEAL
PLACEMENT FOR STRONG OVERRUNNING FLOW ACROSS NORTH
DAKOTA...SETTING US UP FOR A PROLONGED PERIOD OF MODERATE TO HEAVY
PRECIPITATION. WHILE THE MORE STABLE CONDITIONS RESULTS IN MINIMAL
CHANCES FOR SEVERE WEATHER...SOME GUIDANCE DOES TRY TO CREEP
MARGINAL INSTABILITY ACROSS MY FAR SOUTH SO WILL NOT COMPLETELY
RULE THIS OUT. HEAVY RAIN WILL BE THE MAIN IMPACT.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z THURSDAY EVENING)
ISSUED AT 713 PM CDT WED MAY 28 2014
EXPECT BREEZY/WINDY SOUTHEASTERLY WINDS DEVELOPING OVERNIGHT AND
THURSDAY AS A STORM SYSTEM TRACKS FROM MONTANA NORTHEASTWARD TO
CANADA. SOME SHOWERS/THUNDERSTORMS ARE POSSIBLE ACROSS THE WEST
/KISN/ OVERNIGHT. THE ASSOCIATED COLD FRONT SLOWLY MOVES INTO THE
STATE BY THURSDAY AFTERNOON WITH WINDS SHIFTING TO THE
WEST/NORTHWEST BEHIND IT. SHOWERS/THUNDERSTORMS ARE EXPECTED TO
DEVELOP ALONG THIS FRONT POSSIBLY AFFECTING KISN/KDIK LATE
AFTERNOON. NOT ENOUGH CONFIDENCE IN TIMING OR PLACEMENT TO MENTION
IN THE TAFS YET...ESPECIALLY SINCE PRECIP MAY OCCUR AFTER 00Z FRI.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...JNS
SHORT TERM...TM
LONG TERM...NH
AVIATION...JNS
AREA FORECAST DISCUSSION
NWS GRAND FORKS ND
1232 PM CDT TUE MAY 27 2014
.UPDATE...
ISSUED AT 1232 PM CDT TUE MAY 27 2014
EARLY AFTN UPDATE FOCUSED MORE ON POPS. CAN SEE SOME CU
DEVELOPMENT AHEAD OF SFC BOUNDARY ROUGHLY FROM WRN GF COUNTY
THROUGH RANSOM/SARGENT COUNTY. 4KM WRF SHOWS SOME CONVECTION
DEVELOP ALONG THIS BOUNDARY AND PETER OUT AS IT MOVES INTO
MN...WITH A SECOND BAND MOVING THROUGH LATER TONIGHT. GFS/NAM/RUC
ALL APPEAR TO HAVE MUCH TOO WIDESPREAD QPF AMOUNTS AND LEANING
TOWARD THE 4KM WRF SOLUTION...WITH MOST CONFIDENCE IN SERN ND
WHERE THERE IS THE MOST SOLAR AND CU IS BEGINNING TO DEVELOP.
STILL HAVE CHANCE POPS OVER DVL REGION BUT REMOVED POPS A BIT
FASTER THAN PREV FCST AS BEST INSTABILITY (STILL NEEDS TO OVERCOME
CIN) WILL BE ACROSS THE SOUTH. OVERALL NOT A LOT OF FORCING BUT DEW
POINTS ARE IN THE MID 50S...SO MOST ACTIVITY SHOULD DECLINE BY MID
EVENING WITH LOSS OF SOLAR.
UPDATE ISSUED AT 931 AM CDT TUE MAY 27 2014
LATEST OBS SHOW SFC BOUNDARY BETWEEN MINOT AND RUGBY WITH MOST
CONVECTIVE ACTIVITY WEST OF BIS AND LAKE SAKAKAWEA BEGINNING TO
WEAKEN. LATEST RAP SHOWING INCREASING CIN OVER EASTERN ND AND
MODELED SOUNDINGS (12Z NAM) SHOW NEG ENERGY "DECREASING" TO ABOUT
NEG 13 J/KG BY 21Z...THEN INCREASING QUICKLY WITH LOWERING SUN
ANGLE. LIKE THE IDEA OF CHANCE POPS VS LIKELIES GIVEN THE CIN AND
WEAK LLJ FLOW THIS EVENING. WILL MAINLY ADDRESS TEMPS WITH THIS
FCST AND NO SIGNIFICANT CHANGES TO POPS.
UPDATE ISSUED AT 628 AM CDT TUE MAY 27 2014
NO FORECAST CHANGES MADE THIS UPDATE PERIOD.
&&
.SHORT TERM...(TODAY THROUGH WEDNESDAY)
ISSUED AT 330 AM CDT TUE MAY 27 2014
FORECAST CHALLENGE WILL CONTINUE TO BE WARM TEMPERATURES AND PCPN
CHANCES. MODELS IN FAIR AGREEMENT AND WILL USE BLEND.
IN THE NEAR TERM WILL BE MONITORING WEAK CONVECTION OVER THE NW FA
TO SEE HOW FAR EAST IT GETS BEFORE WEAKENING.
OTHERWISE WEAK SURFACE BOUNDARY ACROSS THE WESTERN DAKOTAS WILL
PROPAGATE EAST INTO THE CENTRAL DAKOTAS THIS AFTERNOON. AIRMASS
AHEAD OF BOUNDARY BECOMES MODERATELY UNSTABLE WITH LI`S TO -4 AND
ML CAPE FROM 500-1000 J/KG. PRECIPITABLE H2O VALUES CONTINUE IN
EXCESS OF AN INCH. APPEARS THAT A WEAK WAVE WILL LIFT NE THIS
AFTERNOON AND MAY PROVIDE SOME MODEST UPPER SUPPORT. STRONGEST DEEP
LAYERED SHEAR REMAINS WEST OF THE FA. OVERALL EXPECT SCT
CONVECTION DEVELOPING WITH BEST POTENTIAL INTO THE EVENING ACROSS
THE DVL BASIN. LOW LEVEL JET NON-EXISTENT SO SHOULD SEE A DIURNAL
WEAKENING WITH LOSS OF HEATING LATER THIS EVENING. THERE WILL BE
SOME CONVECTIVE DEBRIS CLOUD COVER THIS MORNING HOWEVER COLUMN
REMAINS WARM SO ABOVE AVERAGE TEMPERATURES EXPECTED AGAIN TODAY.
WARMEST TEMPERATURES WILL AGAIN BE IN THE SOUTHERN VALLEY AND
ADJACENT PORTIONS WHERE MID 80S AGAIN LIKELY. DEW POINTS LOOK A
LITTLE HIGHER TONIGHT SO MINIMUM TEMPERATURES GENERALLY IN THE 50S
TO LOWER 60S.
BOUNDARY WEAKENS BUT REMAINS OVER THE FA ON WEDNESDAY. AS HAS BEEN
THE CASE DOES NOT APPEAR TO BE ANY UPPER FORCING SO ANY COVERAGE
OF LINGERING PCPN IN QUESTION. FOR NOW WILL HOLD ON TO SLIGHT
CHANCE POPS AS SEE NO REASON TO INCREASE. SAME STORY WITH
TEMPERATURES AS COLUMN REMAINS WARM A DEGREE OF SOLAR WILL IMPACT
HOW WARM WE TOP OUT AT.
.LONG TERM...(WEDNESDAY NIGHT THROUGH MONDAY)
ISSUED AT 330 AM CDT TUE MAY 27 2014
LOW PRESSURE REORGANIZES OVER EASTERN MT WEDNESDAY NIGHT.
ASSOCIATED E-W BOUNDARY ACROSS NORTHERN ND SO WILL CONTINUE WITH
CHANCES ACROSS THE FAR NW LATE.
UPPER RIDGE AMPLIFIES OVER FA ON THURSDAY WITH ASSOCIATED WARMING.
CONVECTIVE TEMPERATURES INCREASE SETTING UP SOME HEALTHY CIN SO
WILL TAKE SOME TIME FOR THE CAP TO GO SO BETTER STORM CHANCES WILL
BE IN THE EVENING. BOUNDARY SLOW MOVING BEING PARALLEL TO THE
UPPER FLOW SO BEST CHANCES WILL AGAIN BE OVER THE DVL
BASIN...MAYBE FARTHER WEST.
FRIDAY-MONDAY...THE UPPER RIDGE WILL BREAK DOWN ON FRIDAY AS AN
UPPER TROUGH PASSES TO NORTH. A SFC BOUNDARY WILL PROGRESS INTO THE
AREA...HELPING TO FOCUS CONVECTIVE ACTIVITY. THE BOUNDARY WILL BE
SLOW TO MOVE SOUTHWARD...WITH FLOW ALOFT PARALLEL TO IT. INCREASING
MID-LEVEL SUBTROPICAL MOISTURE IN SOUTHWEST FLOW ALOFT WILL
CONTRIBUTE TO PWATS ABOVE 1.6 INCHES ALONG THE BOUNDARY.
THUS...RAINFALL POTENTIAL WILL NEED TO BE MONITORED IN ADDITION TO
THE CONVECTIVE THREAT. THE GFS/ECMWF STILL DIFFER WITH RESPECT TO
BOUNDARY POSITION...WITH THE GFS HOLDING THE BOUNDARY CLOSE ENOUGH
TO THE REGION FOR PRECIP CHANCES THROUGH THE WEEKEND...WHILE THE
ECMWF BRINGS A WEAK SFC HIGH IN BY SUNDAY MORNING. THUS...THERE IS
NOT A LOT OF CONFIDENCE TOWARDS THE END OF THE PERIOD. MODELS DO
HINT AT A CONTINUED ACTIVE PATTERN ACROSS THE PLAINS EARLY NEXT WEEK
AS ANOTHER SHORTWAVE TROUGH PUSHES OUT OF THE ROCKIES. AS FOR
TEMPS...VERY WARM CONDITIONS WILL CONTINUE AHEAD OF THE BOUNDARY FOR
FRIDAY INTO SATURDAY...WITH MORE SEASONABLE TEMPS BEHIND IT.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z WEDNESDAY MORNING)
ISSUED AT 628 AM CDT TUE MAY 27 2014
EXPECT VFR CONDITIONS WITH VARIABLE WINDS THROUGH THE PERIOD. THERE
WILL BE SOME ISOLATED SHOWERS AND STORMS MOVING FROM WEST TO EAST
LATER THIS AFTERNOON AND TONIGHT. HAVE MENTIONED SOME THUNDER MAINLY
AT KFAR/KDVL WITH VCSH AT KGFK.
&&
.FGF WATCHES/WARNINGS/ADVISORIES...
ND...NONE.
MN...NONE.
&&
$$
UPDATE...SPEICHER
SHORT TERM...VOELKER
LONG TERM...MAKOWSKI/VOELKER
AVIATION...DK
AREA FORECAST DISCUSSION
NWS GRAND FORKS ND
931 AM CDT TUE MAY 27 2014
.UPDATE...
ISSUED AT 931 AM CDT TUE MAY 27 2014
LATEST OBS SHOW SFC BOUNDARY BETWEEN MINOT AND RUGBY WITH MOST
CONVECTIVE ACTIVITY WEST OF BIS AND LAKE SAKAKAWEA BEGINNING TO
WEAKEN. LATEST RAP SHOWING INCREASING CIN OVER EASTERN ND AND
MODELED SOUNDINGS (12Z NAM) SHOW NEG ENERGY "DECREASING" TO ABOUT
NEG 13 J/KG BY 21Z...THEN INCREASING QUICKLY WITH LOWERING SUN
ANGLE. LIKE THE IDEA OF CHANCE POPS VS LIKELIES GIVEN THE CIN AND
WEAK LLJ FLOW THIS EVENING. WILL MAINLY ADDRESS TEMPS WITH THIS
FCST AND NO SIGNIFICANT CHANGES TO POPS.
UPDATE ISSUED AT 628 AM CDT TUE MAY 27 2014
NO FORECAST CHANGES MADE THIS UPDATE PERIOD.
&&
.SHORT TERM...(TODAY THROUGH WEDNESDAY)
ISSUED AT 330 AM CDT TUE MAY 27 2014
FORECAST CHALLENGE WILL CONTINUE TO BE WARM TEMPERATURES AND PCPN
CHANCES. MODELS IN FAIR AGREEMENT AND WILL USE BLEND.
IN THE NEAR TERM WILL BE MONITORING WEAK CONVECTION OVER THE NW FA
TO SEE HOW FAR EAST IT GETS BEFORE WEAKENING.
OTHERWISE WEAK SURFACE BOUNDARY ACROSS THE WESTERN DAKOTAS WILL
PROPAGATE EAST INTO THE CENTRAL DAKOTAS THIS AFTERNOON. AIRMASS
AHEAD OF BOUNDARY BECOMES MODERATELY UNSTABLE WITH LI`S TO -4 AND
ML CAPE FROM 500-1000 J/KG. PRECIPITABLE H2O VALUES CONTINUE IN
EXCESS OF AN INCH. APPEARS THAT A WEAK WAVE WILL LIFT NE THIS
AFTERNOON AND MAY PROVIDE SOME MODEST UPPER SUPPORT. STRONGEST DEEP
LAYERED SHEAR REMAINS WEST OF THE FA. OVERALL EXPECT SCT
CONVECTION DEVELOPING WITH BEST POTENTIAL INTO THE EVENING ACROSS
THE DVL BASIN. LOW LEVEL JET NON-EXISTENT SO SHOULD SEE A DIURNAL
WEAKENING WITH LOSS OF HEATING LATER THIS EVENING. THERE WILL BE
SOME CONVECTIVE DEBRIS CLOUD COVER THIS MORNING HOWEVER COLUMN
REMAINS WARM SO ABOVE AVERAGE TEMPERATURES EXPECTED AGAIN TODAY.
WARMEST TEMPERATURES WILL AGAIN BE IN THE SOUTHERN VALLEY AND
ADJACENT PORTIONS WHERE MID 80S AGAIN LIKELY. DEW POINTS LOOK A
LITTLE HIGHER TONIGHT SO MINIMUM TEMPERATURES GENERALLY IN THE 50S
TO LOWER 60S.
BOUNDARY WEAKENS BUT REMAINS OVER THE FA ON WEDNESDAY. AS HAS BEEN
THE CASE DOES NOT APPEAR TO BE ANY UPPER FORCING SO ANY COVERAGE
OF LINGERING PCPN IN QUESTION. FOR NOW WILL HOLD ON TO SLIGHT
CHANCE POPS AS SEE NO REASON TO INCREASE. SAME STORY WITH
TEMPERATURES AS COLUMN REMAINS WARM A DEGREE OF SOLAR WILL IMPACT
HOW WARM WE TOP OUT AT.
.LONG TERM...(WEDNESDAY NIGHT THROUGH MONDAY)
ISSUED AT 330 AM CDT TUE MAY 27 2014
LOW PRESSURE REORGANIZES OVER EASTERN MT WEDNESDAY NIGHT.
ASSOCIATED E-W BOUNDARY ACROSS NORTHERN ND SO WILL CONTINUE WITH
CHANCES ACROSS THE FAR NW LATE.
UPPER RIDGE AMPLIFIES OVER FA ON THURSDAY WITH ASSOCIATED WARMING.
CONVECTIVE TEMPERATURES INCREASE SETTING UP SOME HEALTHY CIN SO
WILL TAKE SOME TIME FOR THE CAP TO GO SO BETTER STORM CHANCES WILL
BE IN THE EVENING. BOUNDARY SLOW MOVING BEING PARALLEL TO THE
UPPER FLOW SO BEST CHANCES WILL AGAIN BE OVER THE DVL
BASIN...MAYBE FARTHER WEST.
FRIDAY-MONDAY...THE UPPER RIDGE WILL BREAK DOWN ON FRIDAY AS AN
UPPER TROUGH PASSES TO NORTH. A SFC BOUNDARY WILL PROGRESS INTO THE
AREA...HELPING TO FOCUS CONVECTIVE ACTIVITY. THE BOUNDARY WILL BE
SLOW TO MOVE SOUTHWARD...WITH FLOW ALOFT PARALLEL TO IT. INCREASING
MID-LEVEL SUBTROPICAL MOISTURE IN SOUTHWEST FLOW ALOFT WILL
CONTRIBUTE TO PWATS ABOVE 1.6 INCHES ALONG THE BOUNDARY.
THUS...RAINFALL POTENTIAL WILL NEED TO BE MONITORED IN ADDITION TO
THE CONVECTIVE THREAT. THE GFS/ECMWF STILL DIFFER WITH RESPECT TO
BOUNDARY POSITION...WITH THE GFS HOLDING THE BOUNDARY CLOSE ENOUGH
TO THE REGION FOR PRECIP CHANCES THROUGH THE WEEKEND...WHILE THE
ECMWF BRINGS A WEAK SFC HIGH IN BY SUNDAY MORNING. THUS...THERE IS
NOT A LOT OF CONFIDENCE TOWARDS THE END OF THE PERIOD. MODELS DO
HINT AT A CONTINUED ACTIVE PATTERN ACROSS THE PLAINS EARLY NEXT WEEK
AS ANOTHER SHORTWAVE TROUGH PUSHES OUT OF THE ROCKIES. AS FOR
TEMPS...VERY WARM CONDITIONS WILL CONTINUE AHEAD OF THE BOUNDARY FOR
FRIDAY INTO SATURDAY...WITH MORE SEASONABLE TEMPS BEHIND IT.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z WEDNESDAY MORNING)
ISSUED AT 628 AM CDT TUE MAY 27 2014
OVERALL EXPECT VFR CONDITIONS WITH MAINLY MID/UPPER LEVEL CLOUDS
THINNING DURING THE DAY. THUNDERSTORMS ARE EXPECTED TO DEVELOP
OVER THE CENTRAL DAKOTAS MOVING EAST THIS EVENING IN AREAS ALONG
AND EAST OF THE VALLEY. THUNDERSTORM COVERAGE LOOKS SPOTTY AND
SHOULD DIMINISH LATER THIS EVENING.
&&
.FGF WATCHES/WARNINGS/ADVISORIES...
ND...NONE.
MN...NONE.
&&
$$
UPDATE...SPEICHER
SHORT TERM...VOELKER
LONG TERM...MAKOWSKI/VOELKER
AVIATION...VOELKER
AREA FORECAST DISCUSSION
NWS BISMARCK ND
1252 AM CDT TUE MAY 27 2014
.UPDATE...
ISSUED AT 1251 AM CDT TUE MAY 27 2014
UPDATED MAINLY FOR CONVECTION ACROSS SOUTHWEST AND CENTRAL NORTH
DAKOTA...BASED ON LATEST SATELLITE AND RADAR IMAGERY.
THUNDERSTORMS HAVE SHOWN A DOWNTREND OVER THE PAST HOUR AND
CURRENTLY NO SEVERE WEATHER PRODUCTS ARE IN EFFECT. LATEST HRRR
SHOWS THE LINE OF CONVECTION MOVING TOWARD BISMARCK DISSIPATING
QUICKLY AS IT APPROACHES BISMARCK. CONVECTION ACROSS THE NORTH
CENTRAL HAS ALL BUT MOVED OUT OF THE FORECAST AREA AND REMAINS
BELOW SEVERE LIMITS.
UPDATE ISSUED AT 953 PM CDT MON MAY 26 2014
THE 01 UTC HRRR SUGGESTS THAT THE SUPERCELL ACROSS DUNN COUNTY AND
MULTI CELL CLUSTERS ACROSS SOUTHEAST MCKENZIE AND BILLINGS
COUNTIES AS OF 245 UTC WILL CONTINUE TO PROPAGATE SOUTHEAST OVER
THE NEXT TWO TO FOUR HOURS...POTENTIALLY INTO THE BISMARCK/MANDAN
AREA...DICKINSON...MOTT AND GLEN ULLIN. GIVEN INSTABILITY AND
SHEAR PROFILES SUPPORTIVE OF CONTINUED ORGANIZED CONVECTION...AND A
WEAK LOW LEVEL JET...FOLLOWED CLOSELY TO HRRR FOR POPS. WILL ALSO
HAVE TO MONITOR THE CLUSTER OF STORMS NEAR THE INTERNATIONAL
BORDER. ADDED A SEVERE MENTION FOR ALL POPS THROUGH 06 UTC TONIGHT
FOR NOW AND WILL RE-EVALUATE LATER.
UPDATE ISSUED AT 636 PM CDT MON MAY 26 2014
THIS UPDATE TO FOCUS IN THUNDERSTORMS ACROSS THE NORTHWEST.
TRIMMED POPS SOUTH AND EAST FOR THE EVENING AND LOWERED CLOUDS
ALSO.
UPDATE ISSUED AT 518 PM CDT MON MAY 26 2014
SEVERAL STRONG THUNDERSTORMS ARE IMPACTING NORTHWEST NORTH DAKOTA
AND ADDED LARGE HAIL TO THE WEATHER GRIDS FOR SEVERAL HOURS EARLY
THIS EVENING. OTHERWISE WILL CONTINUE TO UPDATE POPS THROUGH THE
EVENING WITH THE LINE AS IT MOVES EAST.
&&
.SHORT TERM...(THIS AFTERNOON THROUGH TUESDAY)
ISSUED AT 252 PM CDT MON MAY 26 2014
THE MAIN FORECAST CHALLENGE WILL BE THE CONVECTIVE POTENTIAL OVER
WESTERN NORTH DAKOTA THIS AFTERNOON AND EVENING...AND AGAIN OVER
WESTERN AND CENTRAL NORTH DAKOTA TUESDAY.
CONVECTION IS ALREADY FIRING OVER NORTHEASTERN MONTANA ALONG A
SURFACE TROUGH. THE ENVIRONMENT IS CHARACTERIZED BY SFC-BASED CAPE
AROUND 1400 J/KG AND 0-6 KM WIND SHEAR AROUND 40 KNOTS. SOME OF
THESE STORMS COULD BECOME SEVERE LATER THIS AFTERNOON AS THEY MOVE
INTO NORTHWESTERN NORTH DAKOTA...WITH LARGE HAIL AND DAMAGING
WINDS BEING THE PRIMARY THREATS. ADDED SEVERE MENTION TO THE
NORTHWESTERN ZONES FOR LATER THIS AFTERNOON AND EVENING AS A
RESULT.
ONGOING CONVECTION IS EXPECTED TO SLOWLY MOVE EAST INTO CENTRAL
NORTH DAKOTA TONIGHT. HOWEVER...THUNDERSTORM INTENSITY SHOULD
DECREASE AS THE BOUNDARY LAYER STABILIZES DUE TO LOSS OF DAYTIME
HEATING.
BY TUESDAY...THE SURFACE TROUGH IS PROGGED TO STALL OVER CENTRAL
NORTH DAKOTA. INCREASING MUCAPE VALUES AROUND 1500 J/KG COMBINED
WITH A WEAK UPPER WAVE WILL GENERATE CHANCE TO LIKELY POPS OVER
CENTRAL NORTH DAKOTA TUESDAY AFTERNOON. HOWEVER...IT LOOKS LIKE
THE BEST DEEP LAYER SHEAR WILL LIFT NORTH INTO CANADA TUESDAY
AFTERNOON. GIVEN THE MARGINAL DEEP LAYER SHEAR...REMOVED SEVERE
MENTION FROM TUESDAY`S FORECAST...CONSISTENT WITH THE LATEST SPC
DAY 2 OUTLOOK. HOWEVER...STRONG THUNDERSTORMS WILL STILL BE
POSSIBLE WITH SMALL HAIL AND GUSTY WINDS POSSIBLE IN THE STRONGER
STORMS.
.LONG TERM...(TUESDAY NIGHT THROUGH MONDAY)
ISSUED AT 252 PM CDT MON MAY 26 2014
FORECAST HIGHLIGHTS IN THE LONG TERM PERIOD WILL BE WARM
TEMPERATURES WEDNESDAY AND THURSDAY FOLLOWED BY A COOL DOWN FRIDAY
THROUGH THE WEEKEND...ALONG WITH CHANCES FOR STRONG TO SEVERE
THUNDERSTORMS WEDNESDAY...THURSDAY...AND FOR PORTIONS OF THE AREA
FRIDAY.
FOR TUESDAY EVENING...UPPER LEVEL LOW PRESSURE SYSTEMS OVER NORTHERN
TEXAS AND THE PACIFIC NORTHWEST WITH AN UPPER LEVEL RIDGE EXTENDING
FROM THE DESERT SOUTHWEST NORTHEAST INTO THE CENTRAL PLAINS.
POSSIBLE STRONG TO SEVERE CONVECTION FROM TUESDAY AFTERNOON WILL BE
ONGOING OR EXITING OVER MY EASTERN COUNTIES TUESDAY EVENING AS AN
EMBEDDED S/WV IMPULSE TRACKS EAST ACROSS NORTH DAKOTA. RIDGE AXIS
BUILDS NORTH ACROSS THE DAKOTAS LATER TUESDAY NIGHT INTO WEDNESDAY
MORNING...AND SHOULD ACT TO STEER ANY OTHER EMBEDDED WAVES NORTHERLY
ACROSS EASTERN MONTANA...PERHAPS GRAZING WEST OR NORTH CENTRAL NORTH
DAKOTA DURING THE AM HOURS. WE ARE THEN VERY MUCH CAPPED DURING THE
DAY WEDNESDAY WITH STRONG SOUTHERLY FLOW/WAA ACROSS THE REGION. BEST
CHANCES FOR STORMS WEDNESDAY NIGHT WILL BE ACROSS THE WEST CLOSER TO
SOUTHWESTERLY FLOW ALOFT AND NEAR A SFC TROUGH NEARING THE MT/ND
BORDER.
SFC TROUGH MOVES SLOWLY EAST ACROSS WESTERN INTO CENTRAL NORTH
DAKOTA THURSDAY AFTERNOON AND THURSDAY NIGHT...AND WILL BE THE FOCUS
FOR DIURNALLY DRIVEN THUNDERSTORMS...SOME POTENTIALLY SEVERE GIVEN
THE INSTABILITY ADVERTISED. MID LEVEL SUPPORT UNCERTAIN. ANOTHER
ROUND OF STORMS POSSIBLE OVER MY SOUTHEAST ON FRIDAY AS THE SFC
TROUGH STALLS ACROSS THE FAR SOUTH CENTRAL...NORTHEAST THROUGH THE
JAMES AND RED RIVER VALLEYS.
UNCERTAINTY RAMPS UP FOR THE COMING WEEKEND AND INTO EARLY NEXT
WEEK...WITH MODELS DISAGREEING ON THE EVOLUTION OF AN AREA OF UPPER
LEVEL LOW PRESSURE DEVELOPING OVER THE DESERT SOUTHWEST AND THE
TIMING AND TRACK OF THIS FEATURE AS IT IS EVENTUALLY EJECTED NORTH
AND EAST. WHICHEVER MODEL VERIFIES...COOLER TEMPERATURES ARE
FORECAST THROUGH THE WEEKEND...AND EVENTUALLY WILL SEE PRECIPITATION
CHANCES INCREASE AS THE LOW APPROACHES AND MOVES THROUGH THE REGION.
ALLBLEND MODEL GUIDANCE WAS USED FOR NOW.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT)
ISSUED AT 1251 AM CDT TUE MAY 27 2014
CONVECTION ONGOING AT TAF ISSUANCE FOR KDIK. UNSURE IF CONVECTION
WILL HOLD TOGETHER AS IT MOVES INTO BISMARCK BUT DID INCLUDE A
MENTION OF THUNDER AT KBIS FOR NOW FROM 06-08Z. OTHERWISE VFR
CONDITIONS WITH A GENERAL SOUTHERLY FLOW LATE TONIGHT INTO
TUESDAY. EXPECT CONVECTION TO FIRE AGAIN ACROSS THE AREA ON
TUESDAY WITH THE GREATEST THREAT EARLIER IN THE DAY AT KDIK THEN
SPREADING INTO KMOT AND KBIS MID DAY TO EARLY AFTERNOON...AND KJMS
MID TO LATE AFTERNOON. KISN SHOULD HAVE THE LEAST THREAT OF
CONVECTION ON TUESDAY.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...TWH
SHORT TERM...TM
LONG TERM...NH
AVIATION...TWH
AREA FORECAST DISCUSSION
NWS NORMAN OK
339 AM CDT TUE MAY 27 2014
.DISCUSSION...
FORECAST CONCERN REMAINS SQUARELY FOCUSED ON PRECIPITATION CHANCES
THROUGH TODAY.
CURRENTLY... AN MCV... WHICH DEVELOPED LAST EVENING... CONTINUES TO
CHURN OVER WRN OK... WELL VISUALIZED BY THE MESONET OBS AND RADAR
MOSAIC. SHOWERS AND THUNDERSTORMS ASSOCIATED WITH THIS MCV CONTINUE
TO EVOLVE SLOWLY THIS MORNING... WITH THE MAIN AREA OF PRECIP
CONTINUING TO LIFT NORTHWARD ACROSS W/NW OK. S/SE OF THIS FEATURE...
A LARGER AREA OF THUNDERSTORMS HAS CONTINUED TO MOVE E/NE ACROSS NRN
TX. THIS CONVECTION WAS INITIALLY ASSOCIATED WITH A SECOND MCV
IN CENTRAL TX... BUT NOW IT`S DRIVEN MORE BY THE CUTOFF LOW...
WITH MAINTENANCE PROVIDED BY A MODERATE LLJ AND DECENT ISENTROPIC
ASCENT IN THE 305-310 K LEVELS. SPEAKING OF OUR CUTOFF LOW...
IT`S FINALLY ON THE MOVE... WITH CURRENT WV PLACING IT NEAR/OVER
THE ERN TX PANHANDLE/OK BORDER.
MESOSCALE GUIDANCE... PRIMARILY FROM THE HRRR AND RAP... CONTINUE TO
SUGGEST A SLIGHT FILLING IN OF CONVECTION BETWEEN THE ACTIVITY
ASSOCIATED WITH THE MCV AND THE CONVECTION JUST SOUTH OF THE RED
RIVER IN NRN TX. DISCLAIMER... AND AS MANY HAVE NOTICED...
MESOSCALE GUIDANCE HAS NOT BEEN VERY RELIABLE OVER THE PAST 3 TO 4
DAYS... AS OVER CONVECTING HAS BEEN A PROBLEM WITH MULTIPLE
RUNS/MODELS. HOWEVER... THROUGH 0830Z... UPDRAFTS HAVE CONTINUED
TO DEVELOP WELL NE OF THE WICHITA MTNS AND JUST WEST OF I-44.
MEANWHILE... THE AREA OF RAIN ACROSS NRN TX IS STARTING TO LIFT
NORTHWARD INTO SRN OK. IT APPEARS THAT THE INFLUENCE FROM THE
SYNOPTIC SCALE IS BEGINNING TO WIN OUT OVER THAT OF THE
MESOSCALE... THINK MCV VS CUTOFF LOW. WITH THAT SAID... IT`S GOING
TO BE ANOTHER WAIT AND SEE MORNING REGARDING THE EVOLUTION OF THIS
CONVECTION THROUGH SUNRISE. ALTHOUGH NOT OVERLY OPTIMISTIC...
EXPECT ISOLATED SHOWERS AND THUNDERSTORMS TO CONTINUE TO DEVELOP
OVER THE NEXT 2 TO 3 HOURS ACROSS SRN OK... POSSIBLY BRIDGING THE
GAP BETWEEN THE NORTH AND SOUTH CONVECTION. FIRST STAB WOULD BE
ISOLATED SHOWERS/THUNDER WILL BE BUILDING INTO CENTRAL OK NEAR OR
JUST AFTER SUNRISE.
THROUGH THE MORNING... INITIALLY ISOLATED CONVECTION WILL BECOME
MORE SCATTERED IN NATURE... WITH CHANCES FOR PRECIP INCREASING
THROUGH THE LATE MORNING ACROSS CENTRAL OK AS THE H500 CUTOFF LOW
TAKES A TRACK ALONG THE RED RIVER VALLEY THROUGH NOON. RAIN CHANCES
WILL DIMINISH QUICKLY ACROSS WRN AND CENTRAL OK THROUGH THE AFTN...
AS SHOWERS AND STORMS PUSH INTO ERN OK. WITH THE UPPER LOW SINKING
ACROSS THE ARKLATEX OVERNIGHT... LINGERING RAIN CHANCES WILL EXIST
ACROSS ERN OK... BUT THEY WILL BE LOW.
FOR WEDNESDAY... CANNOT RULE OUT SOME ISOLATED SHOWERS ACROSS
PORTIONS OF ERN AND POSSIBLY CENTRAL OK. BY 18Z WED... THE H500
CUTOFF LOW WILL SLOW AND LINGER OVER THE ARKLATEX. TO THE WEST...
ACROSS THE SRN ROCKIES A STEEP RIDGE WILL BUILD INTO THE NRN
PLAINS AS A DIGGING SHORTWAVE DIVES INTO THE PACNW. AS THE RIDGE
BUILDS INTO THE MID-MISSOURI VALLEY... THE CUTOFF LOW WILL STALL
OUT OVER THE LOWER MISSISSIPPI VALLEY BY THURSDAY MORNING. IN
SHORT... BASICALLY A REX BLOCK WILL DEVELOP OVER THE CENTRAL
CONUS. THIS BLOCKING PATTERN WILL RESULT IN A FAIRLY STAGNANT
SYNOPTIC PATTERN... RESULTING IN NEAR CONTINUAL PRECIP CHANCES FOR
PORTIONS OF THE SRN PLAINS... THE OZARKS... AND TO THE GULF COAST.
GIVEN OK AND NRN TX WILL BE ON THE NW SIDE OF THE CUTOFF LOW...
CHANCES WILL BE SLIGHT... WITH ISOLATED SHOWERS POSSIBLE ACROSS
ERN OK AT VARIOUS TIMES THROUGH SAT BEFORE THE BLOCKING PATTERN
BEGINS TO BREAK DOWN LATE IN THE WEEKEND WITH THE ARRIVAL OF A
DIGGING TROUGH ON THE WEST COAST.
AFTER SEASONABLE HIGHS THIS WEEK... EXPECT A SLOW WARM UP FROM
SUNDAY INTO MONDAY... WITH HIGHS NEARING THE UPPER 80S TO 90S ONCE
AGAIN. PRECIP CHANCES WILL REMAIN VERY LOW... WITH ONLY A SLIGHT
CHANCE ACROSS FAR NRN OK SUN-TUE AS A FEW WEAK SHORTWAVES TRAVERSE
THE WRN TROUGH... RIDING ACROSS THE CENTRAL PLAINS.
JTK
&&
.PRELIMINARY POINT TEMPS/POPS...
OKLAHOMA CITY OK 77 61 84 63 / 60 20 20 10
HOBART OK 79 59 86 60 / 50 10 0 10
WICHITA FALLS TX 82 62 86 63 / 40 10 10 10
GAGE OK 82 59 88 60 / 20 0 0 0
PONCA CITY OK 77 61 85 64 / 50 20 10 10
DURANT OK 77 64 82 65 / 60 40 30 20
&&
.OUN WATCHES/WARNINGS/ADVISORIES...
OK...NONE.
TX...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS PORTLAND OR
226 PM PDT TUE MAY 27 2014
.SYNOPSIS...AN UPPER LEVEL LOW OFF THE COAST WILL SWING ONSHORE
TUESDAY NIGHT AND WEDNESDAY FOR INCREASING SHOWERS WITH POSSIBLY A
FEW THUNDERSTORMS. A SURFACE THERMAL TROUGH WILL PROVIDE WARMER
TEMPERATURES LATE IN THE WEEK AS A BROAD UPPER TROUGH HOLDS OVER THE
AREA...AND MAINTAINS A THREAT FOR AFTERNOON MOUNTAIN SHOWERS AND
THUNDERSTORMS.
&&
.SHORT TERM...TUESDAY AFTERNOON THROUGH FRIDAY...FORECAST CONCERNS
REVOLVE AROUND CONVECTIVE EVOLUTION THROUGH WEDNESDAY. AREA OF SLOW
MOVING SHOWERS IN THE COAST RANGE WHERE THEY WERE GENERALLY PROGGED
TO FORM TODAY...AND EVEN SOME ON THE WEST SLOPES OF THE CASCADES.
SPC MESOANALYSIS BASED ON THE RAP 40KM MODEL SUGGESTS THE CAP IS
JUST ABOUT ERODED OFFSHORE AND IS ERODING INLAND...AND THIS IS
CONFIRMED BY ACARS/AMDAR SOUNDINGS OUT OF KPDX WITH THE MID LEVEL
WARM NOSE AROUND 750 MB GETTING LESS PRONOUNCED...BUT STILL THERE.
WE ARE STARTING TO SEE THE UPPER TROUGH PUSH CLOSER TO SHORE...AND
UPPER LEVEL TEMPERATURES ARE DROPPING WHICH IS AIDING THE CAP
EROSION...BUT THIS PROCESS IS TAKING SOME TIME INLAND GIVEN THE
BROKEN CLOUD COVER. LATER THIS AFTERNOON AND EVENING THE UPPER
TROUGH AXIS DRIFTS CLOSER TO SHORE AND THE CAP EASES A BIT MORE.
MODEL INSTABILITY PARAMETERS STILL LOOK REALLY WEAK...BUT VARIOUS
CONVECTIVE ALLOWING MODELS DRIFT THE CURRENT AREA OF SHOWERS WITH
SOME 50DBZ ECHOES THROUGH MUCH OF THE NORTHERN HALF OF THE
AREA...MAINLY ALONG THE COAST RANGE AND WILLAPA HILLS THEN SPREADING
INLAND TO NEAR THE FOOTHILLS THIS EVENING. ENOUGH INSTABILITY MAY
EXIST TO POP AN ISOLATED T-STORM OR TWO. INSTABILITY PARAMETERS
WEAKEN THROUGH THE NIGHT INLAND AND SHOULD JUST BE SHOWERS BY TIME
THEY GET TO THE CASCADES. PRECIPITABLE WATER VALUES ARE NOT VERY
HIGH...BUT THE SHOWERS AND STORMS ARE SOMEWHAT SLOW MOVING WHICH MAY
LEAD TO OCCASIONAL MODERATE RAINFALL.
TONIGHT...THESE SHOWERS WILL CONTINUE EAST INTO THE CASCADES. MORE
WIDESPREAD SHOWER DEVELOPMENT IS EXPECTED ALONG THE COAST TONIGHT
AND SPREADING INLAND OVERNIGHT INTO WEDNESDAY AS THE UPPER LOW MOVES
ONSHORE. THE UPPER LOW SHOULD REACH THE COAST BY MIDNIGHT...BE OVER
THE VALLEY BY DAYBREAK. THE CORE OF THE UPPER LOW WILL ALREADY BE
EAST OF THE CASCADES IN THE AFTERNOON. THUNDERSTORMS ARE POSSIBLE AT
THE COAST OVERNIGHT...AND INLAND AS EARLY AS TOMORROW MORNING....BUT
EITHER WAY WEDNESDAY LOOKS TO BE COOL AND SHOWERY. FREEZING LEVELS
LOWER TO ABOUT 5K FEET...AND THUS SOME SMALL HAIL IS POSSIBLE IN THE
HEAVIER SHOWERS. SNOW LEVELS WILL DROP TO APPROXIMATELY 4500 FEET
AND A SLUSHY INCH OF SNOW WILL BE POSSIBLE OVER SANTIAM AND
WILLAMETTE PASSES AND POSSIBLY AT GOVERNMENT CAMP EARLY WEDNESDAY
MORNING. ANY SNOW IMPACTS WILL BE SHORT LIVED DUE TO THE STRONG
SOLAR INPUT THIS TIME OF YEAR. MODELS SHOW GREATER INSTABILITY
WEDNESDAY WITH MIXED LAYER CAPE AROUND 300 J/KG...ENOUGH TO SUPPORT
THE SLIGHT CHANCE FOR THUNDERSTORM MENTION.
THE UPPER LOW PULLS EAST BUT ITS TROUGH AXIS WILL LINGER OVER THE
AREA INTO THURSDAY...THUS EXPECT CLOUDS TO LINGER AROUND WEDNESDAY
NIGHT INTO EARLY THURSDAY WITH SHOWERS GENERALLY DECREASING FROM
SOUTH TO NORTH...HANGING ON THE LONGEST ALONG AND NORTH OF THE
COLUMBIA RIVER THURSDAY. A SURFACE THERMAL TROUGH OVER NORTHERN CA
WILL EXPAND NORTHWARD INTO SOUTHERN OREGON THURSDAY AFTERNOON AND
TEMPERATURES WILL REBOUND CLOSER TO NORMAL.
FRIDAY THE AIRMASS CONTINUES TO WARM AS A SECONDARY UPPER LOW DIGS
OFF THE CALIFORNIA COAST. A THETA-E RIDGE BUILDS ALONG THE CASCADES
IN THE SW FLOW ALOFT...AND THERE IS A CHANCE FOR A SHOWER OR T-STORM
IN THESE AREAS LATER IN THE DAY. MOST AREAS ELSEWHERE REMAIN DRY AND
SIGNIFICANTLY WARMER...WITH UPPER 70S TO LOW 80S FOR THE INTERIOR
LOWLANDS. KMD
.LONG TERM...FRIDAY NIGHT THROUGH MONDAY...AN UPPER LEVEL TROUGH
WILL REMAIN OVER THE PAC NW FROM FRI NIGHT THROUGH NEXT WEEKEND.
SOME OF THE FCST MODEL ENSEMBLES ARE INDICATING THAT THE TROUGH
COULD DEVELOP INTO A CLOSED LOW ON SATURDAY. WILL KEEP A CHANCE FOR
SHOWERS AND THUNDERSTORMS OVER THE CASCADES LATE FRI THROUGH SUNDAY
NIGHT...MAINLY DURING THE AFTERNOON AND EVENING HOURS.
ELSEWHERE...EXPECT DRY AND WARM CONDITIONS TO REMAIN IN CONTROL.
MAINLY ONSHORE FLOW OVER THE EXTENDED PERIOD SHOULD MEAN OVERNIGHT
AND MORNING CLOUDS AT THE COAST...POSSIBLY PUSHING INTO PARTS OF THE
INTERIOR VALLEYS. INLAND VALLEY HIGHS WILL LIKELY REACH WELL INTO
THE 70S OVER THE WEEKEND...RUNNING ABOUT 5 DEGREES ABOVE SEASONAL
NORMALS. THE UPPER LEVEL TROUGH WILL FINALLY PUSH EAST OF THE REGION
EARLY NEXT WEEK...BUT ANOTHER WEEK SHORTWAVE MAY PUSH IN ON MONDAY.
PYLE
&&
.AVIATION...VFR PREVAILS ACROSS THE AREA EARLY THIS AFTERNOON
ALTHOUGH SHOWER ACTIVITY HAS STARTED TO PICK UP OVER THE COAST
RANGE AND HIGHER TERRAIN IN SW WA. VFR TO PREVAIL THROUGH AT LEAST
07Z WED...BUT MAY BE SOME ISOLATED MVFR CIGS THROUGH THIS EVENING
OVER THE COAST RANGE AND IN SW WA DUE TO THE SHOWER ACTIVITY. BETTER
CHANCE FOR MVFR ALONG THE COAST...COAST RANGE AND SW WA OVERNIGHT AS
REMNANTS OF THE UPPER LOW MOVE INLAND OVER THOSE AREAS AND ONSHORE
LOW-LEVEL FLOW INCREASES.
KPDX AND APPROACHES...VFR TO PREVAIL THROUGH AT LEAST 12Z WED.
STILL EXPECTING ISOLATED TO SCATTERED SHOWER ACTIVITY AT THE
TERMINAL AND VICINITY THROUGH 03Z WED. WILL ALSO MAINTAIN A 10
PERCENT CHANCE OF THUNDERSTORMS WITHIN 10 MILES OF THE TERMINAL.
ONSHORE LOW-LEVEL FLOW INCREASES AFTER 12Z WED...WHICH MAY RESULT
IN MORNING AREAS OF MVFR CIGS UNTIL 18Z WED. WEISHAAR.
&&
.MARINE...SURFACE LOW PRES CENTER JUST SOUTH TO SOUTHWEST OF BUOY
46404 AT 20Z. NOT MUCH LEFT OF THE LOW BY THIS EVENING. REMNANTS
FORECAST TO MOVE ASHORE NEAR NEWPORT BETWEEN 06Z AND 12Z WED.
SURFACE GRADIENTS NOT ALL THAT IMPRESSIVE THROUGH TONIGHT...WITH
WIND SPEEDS AT 15 KT OR LESS.
HIGH PRES DEVELOPS OVER THE WATERS LATE TONIGHT AND THEN SETTLES
OVER THE NE PAC THE REST OF THE WEEK. SURFACE THERMAL LOW PRES
FORMS ALONG THE N CALIFORNIA COAST WED AFTERNOON...AND THEN
SPREADS TO THE S OREGON COAST WED NIGHT AND THU. WIND SPEEDS
INCREASE INTO THE 15 TO 20 KT RANGE WED...WITH THE POTENTIAL FOR
25 KT GUSTS OVER THE S WATERS BEGINNING THU AFTERNOON. LITTLE
CHANGE IN THE OVERALL PATTERN FRI THROUGH THE WEEKEND.
SEAS GENERALLY 3 TO 5 FT THROUGH WED...THEN BUMPING UP INTO THE 5
TO 7 FT RANGE. THE STRONGER N WIND MIDWEEK AND BEYOND WILL CREATE
CHOPPY WIND DRIVEN SEAS...ESPECIALLY S OF CASCADE HEAD LATE IN THE
WEEK AND OVER THE WEEKEND. WEISHAAR.
&&
.PQR WATCHES/WARNINGS/ADVISORIES...
OR...NONE.
WA...NONE.
PZ...NONE.
&&
$$
MORE WEATHER INFORMATION ONLINE AT...
HTTP://WEATHER.GOV/PORTLAND
INTERACT WITH US VIA SOCIAL MEDIA
WWW.FACEBOOK.COM/US.NATIONALWEATHERSERVICE.PORTLAND.GOV
WWW.TWITTER.COM/NWSPORTLAND
THIS DISCUSSION IS FOR NORTHWEST OREGON AND SOUTHWEST WASHINGTON FROM
THE CASCADE CREST TO 60 NAUTICAL MILES OFFSHORE. THE AREA IS COMMONLY
REFERRED TO AS THE FORECAST AREA.
AREA FORECAST DISCUSSION
NWS PORTLAND OR
909 AM PDT TUE MAY 27 2014
.SYNOPSIS...AN UPPER LEVEL LOW OFF THE B.C. COAST WILL MOVE
SOUTH OFF THE COAST TODAY...THEN SWING ONSHORE TUESDAY
NIGHT AND WEDNESDAY FOR INCREASING SHOWERS WITH POSSIBLY A FEW
THUNDERSTORMS. A SURFACE THERMAL TROUGH WILL PROVIDE WARMER
TEMPERATURES LATE IN THE WEEK AS A BROAD UPPER TROUGH HOLDS OVER THE
AREA...AND MAINTAINS A THREAT FOR AFTERNOON MOUNTAIN SHOWERS AND
THUNDERSTORMS.
&&
.MORNING UPDATE...FORECAST CONCERNS REVOLVE AROUND CONVECTIVE
EVOLUTION TODAY. AREA OF SLOW MOVING SHOWERS OFFSHORE SHOULD CONTINUE
TO MIGRATE INLAND TODAY. PRETTY STOUT CAP ON THE MORNING SALEM
SOUNDING...BUT LATER THIS AFTERNOON AND EVENING THE UPPER TROUGH AXIS
DRIFTS CLOSER TO SHORE AND THE CAP SHOULD GET MUCH WEAKER IF NOT
ERODE. MODEL INSTABILITY PARAMETERS STILL LOOK PRETTY WEAK...BUT
VARIOUS CONVECTIVE ALLOWING MODELS DRIFT THE CURRENT AREA OF SHOWERS
OFF THE COAST ONSHORE LATER TODAY WHILE ADDITIONAL SHOWERS POP THIS
AFTERNOON FARTHER INLAND. TWO OF THESE HIGHER TIME RESOLUTION MODELS
INCLUDING THE NSSL CAPS AND HRRR DEPICT SOME INFREQUENT 50 DBZ
ECHOES IN THEIR RADAR REFLECTIVITY OUTPUT IN THE CURRENT AREA OF
ISOLATED THUNDER COVERAGE...BUT ALSO SPREAD SOME FARTHER INLAND FROM
ABOUT SALEM NORTHWARD. THEREFORE...WILL EXPAND THE ISOLATED THUNDER
COVERAGE IN THROUGH THE PORTLAND METRO AS THE CAP LOOKS TO ERODE
ENOUGH LATE TO POP AN ISOLATED T-STORM OR TWO. INSTABILITY
PARAMETERS WEAKEN THROUGH THE NIGHT INLAND AND SHOULD JUST BE
SHOWERS BY TIME THEY GET TO THE CASCADES.
SREF CALIBRATED PROBABILITY OF THUNDERSTORMS HAS BEEN WAVERING
BETWEEN 20-40% OVER THE PAST FEW RUNS...AND TYPICALLY 30% IS A DECENT
THRESHOLD...SO THIS CONTINUES TO SUPPORT SHOWERS WITH MAYBE AN
ISOLATED THUNDERSTORM...BUT FEEL WITH DECENT UPPER FORCING AND THE
CAP IN PLACE THAT THE ONES THAT DO POP MAY HAVE SOME BRIEF KICK TO
THEM. /KMD
.SHORT TERM...TODAY THROUGH THURSDAY NIGHT...WATER VAPOR SATELLITE
IMAGERY SHOWS AN UPPER LEVEL LOW CENTERED NEAR 47N 132W EARLY THIS
MORNING. INFRARED AND RADAR IMAGERY SHOWS A BAND OF SHOWERS
CIRCULATING AROUND THIS LOW AROUND 40 MILES OFFSHORE OF THE SOUTHERN
WASHINGTON AND NORTHERN OREGON COAST. THIS BAND OF SHOWERS WILL MOVE
CLOSER TO THESE COAST LATER THIS MORNING AND POSSIBLY PRODUCE A FEW
SHOWERS.
THE CHANCE FOR SHOWERS WILL INCREASE THIS AFTERNOON AS THE UPPER LOW
AND ASSOCIATED COLD POOL...MOVES SOUTHWARD. AFTERNOON SURFACE HEATING
AFTERNOON WILL INCREASE INSTABILITY AND EXPECT AN INCREASE OF SHOWERS
OVER THE COAST RANGE AND POSSIBLY A FEW THUNDERSTORMS. MODELS
FORECAST
MARGINAL NEGATIVE LI`S AND CAPE VALUES...BETWEEN 300-600 J/KG WITH
LOW QPF PRODUCING SHOWERS...WITH THE GREATEST THREAT OVER THE COAST
RANGE BETWEEN 1 PM AND 5 PM. HAVE GREATER FORECAST CONFIDENCE IN
AFTERNOON SHOWERS THAN AFTERNOON THUNDERSTORMS.
THE THREAT FOR SHOWERS WILL SPREAD INLAND TONIGHT AND WEDNESDAY
MORNING AS THE UPPER LOW MOVES OVER SW WASHINGTON AND NW OREGON.
WEDNESDAY WILL BE THE COOLEST DAY OF THE WEEK AND INLAND0
TEMPERATURES WILL BE AROUND 5 DEGREES BELOW THE SEASONAL NORMAL.
SNOW LEVELS WILL DROP TO APPROXIMATELY 4500 FEET AND A SLUSHY INCH OF
SNOW WILL BE POSSIBLE OVER SANTIAM AND WILLAMETTE PASSES AND POSSIBLY
AT GOVERNMENT CAMP EARLY WEDNESDAY MORNING. ANY SNOW IMPACTS WILL BE
SHORT LIVED DUE TO THE STRONG SOLAR INPUT THIS TIME OF YEAR. MODELS
SHOW GREATER INSTABILITY WEDNESDAY AFTERNOON WITH LI`S AROUND -2C AND
CAPE 700-1000 J/KG...AND THE SLIGHT CHANCE FOR THUNDERSTORMS WILL
CONTINUE.
SHOWERS WILL WEAKEN AND END FROM SOUTH TO NORTH WEDNESDAY NIGHT AND
THURSDAY AS THE UPPER LOW MOVES NE INTO CANADA AND AN UPPER RIDGE
BUILDS OFFSHORE. A SURFACE THERMAL TROUGH OVER NORTHERN CA WILL
EXPAND NORTHWARD INTO SOUTHERN OREGON THURSDAY AFTERNOON AND
TEMPERATURES WILL REBOUND CLOSER TO THE SEASONAL NORMAL. A BROAD
UPPER TROUGH WILL REMAIN OVER THE REGION THURSDAY NIGHT. HARTLEY
.LONG TERM...NO CHANGES. PREVIOUS DISCUSSION FOLLOWS...FRIDAY THROUGH
SUNDAY NIGHT... A TROUGH OF UPPER LEVEL LOW PRESSURE IS EXPECTED TO
REMAIN POSITIONED SQUARELY OVER THE PAC NW TROUGH THE END OF THE WEEK
BEFORE SLOWLY PUSHING EASTWARD NEXT WEEKEND. THIS MAY BRING A THREAT
FOR DIURNAL DAYTIME HEATING DRIVEN SHOWERS AND THUNDERSTORMS...MAINLY
IN THE HIGHER TERRAIN. WILL CARRY A SLIGHT CHANCE OF AFTERNOON AND
EVENING SHOWERS AND THUNDERSTORMS OVER THE CASCADES EACH DAY.
OTHERWISE...EXPECT THE LONG TERM FCST PERIOD WILL BE MOSTLY DRY.
MODEL 850MB TEMPS INDICATE WARMER WEATHER WILL BUILD IN FOR FRI
THROUGH NEXT WEEKEND. EXPECT HIGHS FOR THE INTERIOR LOWLANDS TO REACH
WELL INTO THE 70S. PYLE
&&
.AVIATION...NOT MUCH CHANGE FROM PREVIOUS FORECAST. INCREASING
MID CLOUDS OVER REGION TODAY. GENERALLY VFR THROUGH THE FORECAST
PERIOD. INCREASING INSTABILITY DURING THE AFTERNOON WILL LEAD TO
SHOWER ACTIVITY...BUT RESULTANT CIGS SHOULD STILL REMAIN VFR.
SMALL CHANCE...ABOUT 20 PERCENT...OF THUNDERSTORMS. BEST CHANCE OF
THUNDERSTORMS LOOKS TO BE SW WA AND EXTREME NW OREGON 19Z THROUGH
ABOUT 03Z...CLOSEST TO THE LOW CENTER.
KPDX AND APPROACHES...GENERAL VFR THROUGH THE FORECAST PERIOD.
CIGS AROUND 5000 TO 6000 FT...BUT LIKELY TO LOWER A BIT THIS
EVENING. SHOWER THREAT AFTER 19Z. A MINIMAL THREAT...10 PERCENT
CHANCE OR LESS...OF A THUNDERSTORM WITHIN 10 MILES OF THE TERMINAL
FROM 22Z THROUGH 02Z WED. WEISHAAR.
&&
.MARINE...A 1018 MB SURFACE LOW ABOUT 300 NM W OF CAPE
DISAPPOINTMENT AT 12Z WILL CONTINUE TO WEAKEN TODAY AS IT DRIFTS
SE TOWARD THE COASTLINE. NOT MUCH LEFT OF THE LOW BY 00Z WED.
SURFACE GRADIENTS NOT ALL THAT IMPRESSIVE TODAY THROUGH
TONIGHT...WITH WIND SPEEDS AT 15 KT OR LESS.
HIGH PRES DEVELOPS OVER THE WATERS TONIGHT AND THEN SETTLES OVER
THE NE PAC THE REST OF THE WEEK. SURFACE THERMAL LOW PRES FORMS
ALONG THE N CALIFORNIA COAST WED AFTERNOON...AND THEN SPREADS TO
THE S OREGON COAST WED NIGHT AND THU. WIND SPEEDS INCREASE INTO
THE 15 TO 20 KT RANGE WED...WITH THE POTENTIAL FOR 25 KT GUSTS
OVER THE S WATERS BEGINNING THU.
SEAS GENERALLY 3 TO 5 FT THROUGH THE WEEK. THE STRONGER N WIND
MIDWEEK AND BEYOND WILL CREATE CHOPPY WIND DRIVEN SEAS REACHING 7
TO 9 FT ON THE WATERS S OF NEWPORT BY FRI AND SAT. WEISHAAR.
&&
.PQR WATCHES/WARNINGS/ADVISORIES...
OR...NONE.
WA...NONE.
PZ...NONE.
&&
$$
MORE WEATHER INFORMATION ONLINE AT...
HTTP://WEATHER.GOV/PORTLAND
INTERACT WITH US VIA SOCIAL MEDIA
WWW.FACEBOOK.COM/US.NATIONALWEATHERSERVICE.PORTLAND.GOV
WWW.TWITTER.COM/NWSPORTLAND
THIS DISCUSSION IS FOR NORTHWEST OREGON AND SOUTHWEST WASHINGTON FROM
THE CASCADE CREST TO 60 NAUTICAL MILES OFFSHORE. THE AREA IS COMMONLY
REFERRED TO AS THE FORECAST AREA.
AREA FORECAST DISCUSSION...UPDATED
NWS ABERDEEN SD
1224 PM CDT TUE MAY 27 2014
.UPDATE...
NO MAJOR CHANGES MADE TO THE FORECAST THIS MORNING. DID REMOVE THE
MENTION OF PRECIPITATION FROM THE FAR EASTERN CWA FOR THIS
AFTERNOON AS IT LOOKS TO BE EARLY EVENING BEFORE ANYTHING REACHES
THAT AREA. NO CHANGES MADE TO WINDS OR TEMPERATURES AT THIS TIME.
18Z TAFS DISCUSSION BELOW...
&&
.PREVIOUS DISCUSSION...
.SHORT TERM...TODAY THROUGH THURSDAY
MAIN FOCUS IN THE FORECAST IS ON PRECIP/STORM CHANCES TODAY.
ANOTHER CONVECTIVE COMPLEX IS ON THE HEELS OF LAST NIGHTS ACTIVITY
AND IS CURRENTLY ENTERING SOUTHWEST ND AND NORTHWEST SD. SURFACE
FRONTAL BOUNDARY WILL BE LOCATED FROM NORTH CENTRAL ND INTO
NORTHWEST SD BY LATER THIS AFTERNOON. THIS WILL BE THE MAIN FOCUS
FOR CONVECTION LATER TODAY AS MODERATE INSTABILITY DEVELOPS. ONCE
AGAIN THOUGH...OVERALL SHEAR VALUES ARE WEAK...BUT MODELS DO SHOW
VALUES AROUND 30 KNOTS ALONG AND WEST OF THE MISSOURI RIVER.
CANNOT RULE OUT A FEW STRONG TO SEVERE STORMS OVER THE NORTHWEST
CWA LATER THIS AFTERNOON AS ACTIVITY DEVELOPS ALONG THE FRONT.
MUCH LOWER CONFIDENCE IN THUNDERSTORM POTENTIAL FURTHER EAST.
GENERAL AIR MASS LATER TODAY WILL ONCE AGAIN BE WARM AND
HUMID...WITH VERY LITTLE IN THE WAY OF CAPPING. HI RES MODELS DO
SHOW SOME ISOLATED DEVELOPMENT OVER THE EASTERN CWA...SO HAVE
INCLUDED A SLIGHT CHANCE POPS...BUT CONFIDENCE IN JUST HOW FAR
WEST TO CARRY THIS IS LOW. HAVE A FEELING JUST ABOUT ANYWHERE IN
THE CWA IS GAME FOR SMALL/ISOLATED CELLS LATER THIS AFTERNOON...BUT
THE MAIN FOCUS WILL DEFINITELY BE THE FRONTAL BOUNDARY OVER
CENTRAL/WESTERN DAKOTAS. ANY SUBTLE BOUNDARIES FLOATING AROUND THE
CWA MAY ACT AS A TRIGGER AS WELL...ESPECIALLY WHATEVER BOUNDARY IS
LEFT OVER ACROSS NORTHERN SD FROM THE ND MCS. TAKING A LOOK AT THE
LATEST HRRR RUN COMING IN AND IT SHOWS A CLUSTER OF STRONGER CELLS
ACROSS CORSON/DEWEY COUNTIES AROUND 22Z. TEND TO HAVE RATHER HIGH
CONFIDENCE IN THIS SCENARIO AS IT IS SUPPORTED BY OTHER MODELS AND
IT MAKES SENSE AS WELL GIVEN THE SFC FRONT PLACEMENT BY LATER
TODAY. SHEAR IS STRONGEST HERE AND MODERATE INSTABILITY/WEAK
CAPPING EXIST AS WELL.
CAPPING BECOMES MORE PRONOUNCED OVER THE REGION WEDNESDAY AND
THURSDAY AS UPPER LEVEL HEIGHTS RISE. WILL KEEP FORECAST DRY WITH
VERY WARM TEMPERATURES IN THE MID TO UPPER 80S. SOME AREAS MAY
EVEN HIT 90 DEGREES. WITH DEWPOINTS RIGHT AROUND 60 DEGREES GIVE
OR TAKE...CONDITIONS WILL FEEL A BIT MUGGY.
.LONG TERM...THURSDAY NIGHT THROUGH MONDAY
THE LONG TERM PERIOD STARTS OUT WITH DECENT MID LEVEL RIDGING
ACROSS THE NORTHERN PLAINS AND MOSTLY DRY CONDITIONS. HOWEVER
ENERGY TOPPING THE RIDGE OVER THE WEEKEND WILL BRING ABOUT HEIGHT
FALLS...AND A FOCUSING SURFACE FRONT ADVECTING SLOWLY ACROSS THE
FORECAST AREA. SCT AND EVEN LIKELY POPS SEEM APPROPRIATE FRIDAY
AND SATURDAY BASED ON THE AMOUNT OF INSTABILITY THAT WILL BE
PRESENT OVER THE REGION. BUT DEEP LAYER SHEAR VALUES ARE STILL
PRETTY MARGINAL THROUGH THE WEEKEND...AND THUS HEAVY RAIN
PRODUCERS MIGHT BE THE MAIN THUNDERSTORM THEME. BY LATE WEEKEND
AND EARLY NEXT WEEK THERE ARE SOME DIFFERENCES IN THE
MODELS...ENOUGH THAT FORECASTER CONFIDENCE FOR SUNDAY AND MONDAY
IS SOMEWHAT LOW. THE ECMWF SUPPRESSES THE MAIN BAROCLINIC ZONE/SFC
FRONT FURTHER SOUTH VS THE GFS AND THUS IS COOLER WITH LESS
INSTABILITY AND LESS RAINFALL. HARD TO SAY FOR SURE WHICH MODEL IS
CORRECT. TEMPERATURES WILL START OUT ABOVE NORMAL BUT THEN TREND
TOWARD NORMAL BY THE END OF THE PERIOD.
&&
.AVIATION...
18Z TAFS FOR THE KABR...KATY...KPIR AND KMBG TERMINALS
A WEAK PRESSURE PATTERN WILL RESULT IN LIGHT WINDS. CIGS AND VISBY
WILL REMAIN VFR THOUGH CANT RULE OUT AN ISOLATED/WEAK THUNDERSTORM
DEVELOPING BETWEEN THE KMBG/KABR TERMINALS.
&&
.ABR WATCHES/WARNINGS/ADVISORIES...
SD...NONE.
MN...NONE.
&&
$$
UPDATE...PARKIN
SHORT TERM...TMT
LONG TERM...TDK
AVIATION...CONNELLY
WEATHER.GOV/ABERDEEN
AREA FORECAST DISCUSSION...UPDATED
NWS ABERDEEN SD
1016 AM CDT TUE MAY 27 2014
.UPDATE...
NO MAJOR CHANGES MADE TO THE FORECAST THIS MORNING. DID REMOVE THE
MENTION OF PRECIPITATION FROM THE FAR EASTERN CWA FOR THIS
AFTERNOON AS IT LOOKS TO BE EARLY EVENING BEFORE ANYTHING REACHES
THAT AREA. NO CHANGES MADE TO WINDS OR TEMPERATURES AT THIS TIME.
&&
.PREVIOUS DISCUSSION...
.SHORT TERM...TODAY THROUGH THURSDAY
MAIN FOCUS IN THE FORECAST IS ON PRECIP/STORM CHANCES TODAY.
ANOTHER CONVECTIVE COMPLEX IS ON THE HEELS OF LAST NIGHTS ACTIVITY
AND IS CURRENTLY ENTERING SOUTHWEST ND AND NORTHWEST SD. SURFACE
FRONTAL BOUNDARY WILL BE LOCATED FROM NORTH CENTRAL ND INTO
NORTHWEST SD BY LATER THIS AFTERNOON. THIS WILL BE THE MAIN FOCUS
FOR CONVECTION LATER TODAY AS MODERATE INSTABILITY DEVELOPS. ONCE
AGAIN THOUGH...OVERALL SHEAR VALUES ARE WEAK...BUT MODELS DO SHOW
VALUES AROUND 30 KNOTS ALONG AND WEST OF THE MISSOURI RIVER.
CANNOT RULE OUT A FEW STRONG TO SEVERE STORMS OVER THE NORTHWEST
CWA LATER THIS AFTERNOON AS ACTIVITY DEVELOPS ALONG THE FRONT.
MUCH LOWER CONFIDENCE IN THUNDERSTORM POTENTIAL FURTHER EAST.
GENERAL AIR MASS LATER TODAY WILL ONCE AGAIN BE WARM AND
HUMID...WITH VERY LITTLE IN THE WAY OF CAPPING. HI RES MODELS DO
SHOW SOME ISOLATED DEVELOPMENT OVER THE EASTERN CWA...SO HAVE
INCLUDED A SLIGHT CHANCE POPS...BUT CONFIDENCE IN JUST HOW FAR
WEST TO CARRY THIS IS LOW. HAVE A FEELING JUST ABOUT ANYWHERE IN
THE CWA IS GAME FOR SMALL/ISOLATED CELLS LATER THIS AFTERNOON...BUT
THE MAIN FOCUS WILL DEFINITELY BE THE FRONTAL BOUNDARY OVER
CENTRAL/WESTERN DAKOTAS. ANY SUBTLE BOUNDARIES FLOATING AROUND THE
CWA MAY ACT AS A TRIGGER AS WELL...ESPECIALLY WHATEVER BOUNDARY IS
LEFT OVER ACROSS NORTHERN SD FROM THE ND MCS. TAKING A LOOK AT THE
LATEST HRRR RUN COMING IN AND IT SHOWS A CLUSTER OF STRONGER CELLS
ACROSS CORSON/DEWEY COUNTIES AROUND 22Z. TEND TO HAVE RATHER HIGH
CONFIDENCE IN THIS SCENARIO AS IT IS SUPPORTED BY OTHER MODELS AND
IT MAKES SENSE AS WELL GIVEN THE SFC FRONT PLACEMENT BY LATER
TODAY. SHEAR IS STRONGEST HERE AND MODERATE INSTABILITY/WEAK
CAPPING EXIST AS WELL.
CAPPING BECOMES MORE PRONOUNCED OVER THE REGION WEDNESDAY AND
THURSDAY AS UPPER LEVEL HEIGHTS RISE. WILL KEEP FORECAST DRY WITH
VERY WARM TEMPERATURES IN THE MID TO UPPER 80S. SOME AREAS MAY
EVEN HIT 90 DEGREES. WITH DEWPOINTS RIGHT AROUND 60 DEGREES GIVE
OR TAKE...CONDITIONS WILL FEEL A BIT MUGGY.
.LONG TERM...THURSDAY NIGHT THROUGH MONDAY
THE LONG TERM PERIOD STARTS OUT WITH DECENT MID LEVEL RIDGING
ACROSS THE NORTHERN PLAINS AND MOSTLY DRY CONDITIONS. HOWEVER
ENERGY TOPPING THE RIDGE OVER THE WEEKEND WILL BRING ABOUT HEIGHT
FALLS...AND A FOCUSING SURFACE FRONT ADVECTING SLOWLY ACROSS THE
FORECAST AREA. SCT AND EVEN LIKELY POPS SEEM APPROPRIATE FRIDAY
AND SATURDAY BASED ON THE AMOUNT OF INSTABILITY THAT WILL BE
PRESENT OVER THE REGION. BUT DEEP LAYER SHEAR VALUES ARE STILL
PRETTY MARGINAL THROUGH THE WEEKEND...AND THUS HEAVY RAIN
PRODUCERS MIGHT BE THE MAIN THUNDERSTORM THEME. BY LATE WEEKEND
AND EARLY NEXT WEEK THERE ARE SOME DIFFERENCES IN THE
MODELS...ENOUGH THAT FORECASTER CONFIDENCE FOR SUNDAY AND MONDAY
IS SOMEWHAT LOW. THE ECMWF SUPPRESSES THE MAIN BAROCLINIC ZONE/SFC
FRONT FURTHER SOUTH VS THE GFS AND THUS IS COOLER WITH LESS
INSTABILITY AND LESS RAINFALL. HARD TO SAY FOR SURE WHICH MODEL IS
CORRECT. TEMPERATURES WILL START OUT ABOVE NORMAL BUT THEN TREND
TOWARD NORMAL BY THE END OF THE PERIOD.
&&
.AVIATION...
12Z TAFS FOR THE KABR...KATY...KPIR AND KMBG TERMINALS
AFTER SOME PATCHY MORNING IFR FOG AND CIGS...THE REST OF THE DAY
SHOULD PROVE TO BE VFR AT ALL TERMINALS. THE BEST CHANCE FOR
CONVECTION THROUGH TNT WILL EXIST LATER THIS AFTERNOON AT
KMBG...AND THEN KABR TOWARD SUNSET.
&&
.ABR WATCHES/WARNINGS/ADVISORIES...
SD...NONE.
MN...NONE.
&&
$$
UPDATE...PARKIN
SHORT TERM...TMT
LONG TERM...TDK
AVIATION...TDK
WEATHER.GOV/ABERDEEN
AREA FORECAST DISCUSSION
NWS ABERDEEN SD
426 AM CDT TUE MAY 27 2014
.SHORT TERM...TODAY THROUGH THURSDAY
MAIN FOCUS IN THE FORECAST IS ON PRECIP/STORM CHANCES TODAY.
ANOTHER CONVECTIVE COMPLEX IS ON THE HEELS OF LAST NIGHTS ACTIVITY
AND IS CURRENTLY ENTERING SOUTHWEST ND AND NORTHWEST SD. SURFACE
FRONTAL BOUNDARY WILL BE LOCATED FROM NORTH CENTRAL ND INTO
NORTHWEST SD BY LATER THIS AFTERNOON. THIS WILL BE THE MAIN FOCUS
FOR CONVECTION LATER TODAY AS MODERATE INSTABILITY DEVELOPS. ONCE
AGAIN THOUGH...OVERALL SHEAR VALUES ARE WEAK...BUT MODELS DO SHOW
VALUES AROUND 30 KNOTS ALONG AND WEST OF THE MISSOURI RIVER.
CANNOT RULE OUT A FEW STRONG TO SEVERE STORMS OVER THE NORTHWEST
CWA LATER THIS AFTERNOON AS ACTIVITY DEVELOPS ALONG THE FRONT.
MUCH LOWER CONFIDENCE IN THUNDERSTORM POTENTIAL FURTHER EAST.
GENERAL AIR MASS LATER TODAY WILL ONCE AGAIN BE WARM AND
HUMID...WITH VERY LITTLE IN THE WAY OF CAPPING. HI RES MODELS DO
SHOW SOME ISOLD DEVELOPMENT OVER THE EASTERN CWA...SO HAVE
INCLUDED A SLIGHT CHANCE POPS...BUT CONFIDENCE IN JUST HOW FAR
WEST TO CARRY THIS IS LOW. HAVE A FEELING JUST ABOUT ANYWHERE IN
THE CWA IS GAME FOR SMALL/ISOLD CELLS LATER THIS AFTERNOON...BUT
THE MAIN FOCUS WILL DEFINITELY BE THE FRONTAL BOUNDARY OVER
CENTRAL/WESTERN DAKOTAS. ANY SUBTLE BOUNDARIES FLOATING AROUND THE
CWA MAY ACT AS A TRIGGER AS WELL...ESPECIALLY WHATEVER BOUNDARY IS
LEFT OVER ACROSS NORTHERN SD FROM THE ND MCS. TAKING A LOOK AT THE
LATEST HRRR RUN COMING IN AND IT SHOWS A CLUSTER OF STRONGER CELLS
ACROSS CORSON/DEWEY COUNTIES AROUND 22Z. TEND TO HAVE RATHER HIGH
CONFIDENCE IN THIS SCENARIO AS IT IS SUPPORTED BY OTHER MODELS AND
IT MAKES SENSE AS WELL GIVEN THE SFC FRONT PLACEMENT BY LATER
TODAY. SHEAR IS STRONGEST HERE AND MODERATE INSTABILITY/WEAK
CAPPING EXIST AS WELL.
CAPPING BECOMES MORE PRONOUNCED OVER THE REGION WEDNESDAY AND
THURSDAY AS UPPER LEVEL HEIGHTS RISE. WILL KEEP FORECAST DRY WITH
VERY WARM TEMPERATURES IN THE MID TO UPPER 80S. SOME AREAS MAY
EVEN HIT 90 DEGREES. WITH DEWPOINTS RIGHT AROUND 60 DEGREES GIVE
OR TAKE...CONDITIONS WILL FEEL A BIT MUGGY.
.LONG TERM...THURSDAY NIGHT THROUGH MONDAY
THE LONG TERM PERIOD STARTS OUT WITH DECENT MID LEVEL RIDGING
ACROSS THE NORTHERN PLAINS AND MOSTLY DRY CONDITIONS. HOWEVER
ENERGY TOPPING THE RIDGE OVER THE WEEKEND WILL BRING ABOUT HEIGHT
FALLS...AND A FOCUSING SURFACE FRONT ADVECTING SLOWLY ACROSS THE
FORECAST AREA. SCT AND EVEN LIKELY POPS SEEM APPROPRIATE FRIDAY
AND SATURDAY BASED ON THE AMOUNT OF INSTABILITY THAT WILL BE
PRESENT OVER THE REGION. BUT DEEP LAYER SHEAR VALUES ARE STILL
PRETTY MARGINAL THROUGH THE WEEKEND...AND THUS HEAVY RAIN
PRODUCERS MIGHT BE THE MAIN THUNDERSTORM THEME. BY LATE WEEKEND
AND EARLY NEXT WEEK THERE ARE SOME DIFFERENCES IN THE
MODELS...ENOUGH THAT FORECASTER CONFIDENCE FOR SUNDAY AND MONDAY
IS SOMEWHAT LOW. THE ECMWF SUPPRESSES THE MAIN BAROCLINIC ZONE/SFC
FRONT FURTHER SOUTH VS THE GFS AND THUS IS COOLER WITH LESS
INSTABILITY AND LESS RAINFALL. HARD TO SAY FOR SURE WHICH MODEL IS
CORRECT. TEMPERATURES WILL START OUT ABOVE NORMAL BUT THEN TREND
TOWARD NORMAL BY THE END OF THE PERIOD.
&&
.AVIATION...
06Z TAFS FOR THE KABR...KATY...KPIR AND KMBG TERMINALS
WITH THE LIGHT WINDS IN THE LOW LEVELS ALONG WITH HIGH DEW
POINTS...EXPECT SOME FOG TO FORM TONIGHT AT ALL LOCATIONS WITH
MAYBE SOME VISIBILITIES DOWN TO A MILE AT TIMES.
OTHERWISE...TUESDAY SHOULD BE VFR WITH SOME FEW-SCT CU CLOUDS
FORMING AND THEN DISSIPATING IN THE EVENING.
&&
.ABR WATCHES/WARNINGS/ADVISORIES...
SD...NONE.
MN...NONE.
&&
$$
SHORT TERM...TMT
LONG TERM...TDK
AVIATION...TDK
WEATHER.GOV/ABERDEEN
AREA FORECAST DISCUSSION
NWS MEMPHIS TN
1157 PM CDT MON MAY 26 2014
.UPDATE...
UPDATED TO INCLUDE 06Z AVIATION DISCUSSION BELOW.
&&
.PREV DISCUSSION... /ISSUED 933 PM CDT MON MAY 26 2014/
UPDATE...
MIDEVENING GOES WATER VAPOR IMAGERY SHOWED AN UPPER LOW OVER THE TX
PANHANDLE...LIFTING SLOWLY EAST. EXTENSIVE HIGH CLOUDINESS WAS
SPREADING DOWNSTREAM OF THIS FEATURE...INTO THE MIDSOUTH. CLOUDS
WILL CONTINUE TO INCREASE DURING THE OVERNIGHT...LIMITING
RADIATIONAL COOLING POTENTIAL.
NEWLY ARRIVED 00Z NAM DEPICTED THE MIDSOUTH FREE OF RAIN DURING
THE OVERNIGHT...FOLLOWED BY SHOWERS AND THUNDERSTORMS INCREASING
DURING THE MORNING DAYLIGHT HOURS AS CONVECTIVE TEMPS ARE REACHED.
00Z HRRR SHOWED A POTENTIAL FOR ELEVATED PREDAWN WARM ADVECTION
SHOWERS MAINLY WEST OF THE RIVER.
FORECAST WAS RECENTLY UPDATED TO WITH A SLIGHT NOD GIVEN TO THE
HRRR PREDAWN PRECIP CHANCES. OTHERWISE...FEW OTHER CHANGES.
PWB
&&
.PREV DISCUSSION... /ISSUED 317 PM CDT MON MAY 26 2014/
DISCUSSION...
TEMPERATURES RANGE FROM THE MIDDLE 80S TO AROUND 90 DEGREES EARLY
THIS AFTERNOON. HIGHS ARE PROBABLY STILL ANOTHER HOUR OR SO AWAY
AND WILL LIKELY TOP OUT IN THE UPPER 80S TO LOW 90S. UNLIKE
YESTERDAY LITTLE TO NO CONVECTION IS ON THE RADAR THIS AFTERNOON.
INSTABILITY IS ELEVATED...ENHANCED BY SURFACE DEW POINTS IN THE
MIDDLE 60S. CAPES ARE CURRENTLY RUNNING FROM AROUND 500 TO 1500
J/KG WITH LI`S FROM -2 TO -4C. AN ISOLATED SHOWER OR THUNDERSTORM
CANNOT BE TOTALLY RULED OUT...BUT LACK OF ANY UPPER SUPPORT SUCH
AS WE SAW YESTERDAY OR SURFACE BOUNDARY TO HELP FOCUS LIFT HAS
RESULTED IN A QUIET RADAR.
TONIGHT ANY LINGERING CONVECTION SHOULD DISSIPATE QUICKLY AND
TEMPERATURES WILL FALL INTO THE MID 60S TO LOW 70S.
TOMORROW INTO MIDWEEK...SURFACE HIGH PRESSURE WILL WEAKEN AS IT
SHIFTS EAST AND AN UPPER LOW WILL SHIFT ACROSS THE SOUTHERN
PLAINS ENHANCING RAIN SHOWERS AND THUNDERSTORM CHANCES ACROSS THE
MIDSOUTH. THE GFS IS MUCH MORE BULLISH IN RAINFALL CHANCES AND
RESULTING RAINFALL TOTALS THAN THE ECMWF AND NAM. FORECAST
INSTABILITIES WILL LIKELY BE LOWER THAN GUIDANCE SUGGESTS DUE TO
CLOUD COVER AND WE STILL WILL NOT HAVE ANY WELL DEFINED SURFACE
FEATURES TO HELP FOCUS LIFT. AS A RESULT...LEANING SLIGHTLY
TOWARD THE DRIER SOLUTIONS...EXPECTING SHOWERY PRECIPITATION WITH
EMBEDDED THUNDERSTORMS. THUNDERSTORMS SHOULD REMAIN UNDER SEVERE
LIMITS...ALTHOUGH THIS TIME OF YEAR STORMS CAN PULSE SO AN
ISOLATED SEVERE STORM IS NOT OUT OF THE QUESTION. WILL NOT MENTION
EVEN STRONG STORMS IN THE HAZARDOUS WEATHER OUTLOOK. HIGHS TUESDAY
AND WEDNESDAY WILL STILL BE ABOVE NORMAL...BUT LIKELY 3-6 DEGREES
COOLER THAN TODAY.
THE ECMWF KEEPS THE UPPER LOW INTACT THROUGH THE END OF THE WORK
WEEK AND STALLS IT OVER NORTH LOUISIANA. THE GFS WEAKENS IT
CONSIDERABLY AND TAKES IT NEAR THE GULF COAST IN SOUTH LOUISIANA.
THE LATTER SOLUTION WOULD RESULT IN DRIER AND WARMER CONDITIONS
MIDWEEK. WILL FAVOR THAT SCENARIO...BUT KEEP TEMPERATURES SLIGHTLY
BELOW GFS MOS.
OVER THE WEEKEND INTO NEXT WEEK...A RIDGE WILL BUILD BACK IN.
EXPECT EARLY SUMMER-LIKE CONDITIONS WITH HIGHS IN THE UPPER 80S TO
LOW 90S AND MAINLY AFTERNOON SHOWERS AND THUNDERSTORMS...IN THE
20-30 PERCENT COVERAGE RANGE.
30
&&
.AVIATION...
06Z TAF CYCLE
VFR CONDITIONS WILL PREVAIL OVER THE NEXT 24 HOURS. WINDS WILL
REMAIN SOUTH TO SOUTHWEST 2 TO 5 KTS OVERNIGHT...INCREASING TO 7
TO 10 KTS BY TOMORROW AFTERNOON. CIRRUS CLOUDS WILL FILTER IN
LATE TONIGHT AND ISOLATED SHOWERS ARE EXPECTED TO DEVELOP AFTER
27/10Z. COVERAGE IS EXPECTED TO BE PATCHY SO WENT VCSH. BY 27/15Z
SCATTERED SHOWERS AND THUNDERSTORMS WILL DEVELOP NEAR ALL SITES AS
CONVECTIVE TEMPERATURES ARE REACHED. COVERAGE WILL BE SPARSE
WARRANTING VCTS THROUGH SUNSET. SHOWERS WILL DIMINISH IN COVERAGE
AFTER 28/01Z WITH THE LOSS OF DAYTIME HEATING.
AC3
&&
.MEG WATCHES/WARNINGS/ADVISORIES...
AR...NONE.
MO...NONE.
MS...NONE.
TN...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS HOUSTON/GALVESTON TX
1143 PM CDT MON MAY 26 2014
.DISCUSSION...
SEE 06Z AVIATION DISCUSSION.
&&
.AVIATION...
CONVECTION OVER CENTRAL TEXAS WILL MOVE INTO THE NW ZONES BETWEEN
09-10Z IF ITS HOLD TOGETHER. SHORT TERM MODELS SUPPORT THIS
ACTIVITY HOLDING TOGETHER SO SPED UP THE TIME SHRA/TSRA WILL
DEVELOP AT KCLL AND KUTS. HAVE AGAIN LEANED HEAVILY TOWARD THE
ARW-EAST AND RAP 13 FOR THE TAF PACKAGE. CONFIDENCE IS A BIT
HIGHER NOW THAT THE GFS AND NAM ARE MORE BULLISH WITH RAIN
CHANCES ON TUES MORNING/AFTN. COLD BE SEVERAL ROUNDS OF CONVECTION
ON TUESDAY SO HAVE AN EXTENDED TEMPO GROUP BUT NOT QUITE SURE HOW
ELSE TO HANDLE RAIN CHANCES. POOR AVIATION CONDS ARE EXPECTED TUES
MORNING INTO TUES AFTN WITH SOME MINOR IMPROVEMENT TUESDAY
EVENING. 43
&&
.PREV DISCUSSION... /ISSUED 1025 PM CDT MON MAY 26 2014/
UPDATE...
SEE DISCUSSION FOR EVENING UPDATE.
DISCUSSION...
HEAVY RAINFALL FELL TODAY ACROSS THE CENTRAL PARTS OF OUR CWA WITH
TOTALS UP TO SEVEN INCHES IN JACKSON COUNTY. BECAUSE OF THIS WE
WILL CONTINUE THE FLASH FLOOD WATCH UNTIL 1 PM TOMORROW AFTERNOON.
THE WATCH MIGHT HAVE TO BE EXTENDED OR RECONFIGURED BASED ON WHERE
THE HEAVIEST RAIN SETS UP TOMORROW.
MODELS ARE IN PRETTY GOOD AGREEMENT WITH THE CHANCE OF RAIN
TOMORROW BUT HAVE FOR THE MOST PART HAD TROUBLE INITIALIZING. HIGH
RES ARW AND HRRR SHOW CURRENT CONVECTION IN THE SAN ANGELO AREA
HOLDING TOGETHER AND PUSHING THROUGH OUR AREA TOMORROW MORNING.
HIGH RES NMM AND TEXAS TECH WRF ARE NOT AS CONFIDENT WITH RAINFALL
TOMORROW. ANOTHER ROUND OF RAIN DOES SEEM TO MAKE SENSE THOUGH
GIVEN UPPER LEVEL LOW SPINNING OVER THE TEXAS PANHANDLE WHICH IS
SCHEDULED TO PUSH TO THE EAST. THE NEW 0Z NAM AGAIN SHOWS ANOTHER
SLUG OF PVA HEADING TOWARDS OUR AREA FOR TOMORROW WHICH COULD SET
UP ANOTHER ROUND OF HEAVY RAIN. THE UPPER LEVEL JET ALSO LOOKS TO
TEMPORARILY MOVE US INTO A LFQ IN THE MORNING BUT ONLY TO
TRANSITION INTO CONVERGENT REGIONS (RFQ/ LRQ) OF THE JET BY
AFTERNOON. MODELS DUE SEEM TO BE CONVERGING ON RAIN MAKING IT INTO
OUR NORTHWESTERN ZONES AROUND 5 AM (KCLL) AND THEN PUSHING INTO
HOUSTON AROUND 8 AM. PLEASE STAY TUNED FOR UPDATES AS TIMING AN
EXACT LOCATIONS OF HEAVY RAIN CONTINUE TO GET REFINED. 23
CLIMATE...
RAINFALL TOTALS FOR TODAY:
2.91" - KIAH (RECORD)
3.22" - KHOU (RECORD)
1.51" - KSGR (RECORD)
23/43
PREV DISCUSSION... /ISSUED 744 PM CDT MON MAY 26 2014/
UPDATE...
THE TORNADO WATCH HAS NOW BEEN CANCELLED. NEW ZONES ALREADY OUT.
23
PREV DISCUSSION... /ISSUED 404 PM CDT MON MAY 26 2014/
DISCUSSION...
PROPAGATION OF THE OVERNIGHT PCPN THROUGH SE TX THIS AFTN LIKELY
HELPED BY SPLITTING JET ALOFT/INFLUX OF ABUNDANT LOW-LEVEL MOIST-
URE FROM THE GULF. SAVE FOR THE LEADING TSRA (WHICH PROMPTED THE
WARNINGS) THE REST OF THE ACTIVITY SHOULD CONTINUE TO BE GENERAL-
LY MODERATE/HEAVY RAINFALL PRODUCERS. NOT SEEING MUCH BEHIND THE
SYSTEM...SO WITH THE LOSS OF DAYTIME HEATING WILL EXPECT A BREAK
OVERNIGHT. BUT PER WV IMAGERY ADDITIONAL DISTURBANCES SEEM TO BE
HEADED THIS WAY.
AND SO...THE FCST FOR THE NEXT FEW DAYS SHOULD REMAIN ON THE ACT-
IVE SIDE WITH THE SLOW APPROACH/POSSIBLE STALLING OF THE MAIN UP-
PER LOW OVER SE TX. MOST NOTICEABLE DIFFERENCES FOR THE 12Z RUNS
SEEM TO BE WITH THE END OF PCPN CHCS...WHICH COULD EXTEND TO SAT.
OTHERWISE NOT TOO MANY CHANGES WITH THE GRIDS AS MODELS ARE/HAVE
BEEN HANDLING THIS SYSTEM RATHER CONSISTENTLY. GIVEN THE PROGGED
DYNAMICS AND ONGOING TRENDS THE FCST OF POSSIBLE SEVERE WX/HEAVY
RAINS FOR THE NEXT COUPLE OF DAYS LOOK REASONABLE AT THIS POINT.
&&
.PRELIMINARY POINT TEMPS/POPS...
COLLEGE STATION (CLL) 68 82 69 83 70 / 60 70 50 50 30
HOUSTON (IAH) 69 82 70 84 71 / 40 70 40 60 40
GALVESTON (GLS) 73 82 73 83 74 / 30 60 40 60 40
&&
.HGX WATCHES/WARNINGS/ADVISORIES...
TX...FLASH FLOOD WATCH THROUGH TUESDAY AFTERNOON FOR THE FOLLOWING
ZONES: AUSTIN...BRAZORIA...BRAZOS...BURLESON...CHAMBERS...
COLORADO...FORT BEND...GALVESTON...GRIMES...HARRIS...
HOUSTON...JACKSON...LIBERTY...MADISON...MATAGORDA...
MONTGOMERY...POLK...SAN JACINTO...TRINITY...WALKER...
WALLER...WASHINGTON...WHARTON.
GM...SMALL CRAFT SHOULD EXERCISE CAUTION UNTIL 4 AM CDT TUESDAY FOR
THE FOLLOWING ZONES: WATERS FROM FREEPORT TO THE MATAGORDA
SHIP CHANNEL 20 NM TO 60 NM...WATERS FROM FREEPORT TO THE
MATAGORDA SHIP CHANNEL OUT 20 NM...WATERS FROM HIGH ISLAND
TO FREEPORT 20 TO 60 NM...WATERS FROM HIGH ISLAND TO
FREEPORT OUT 20 NM.
&&
$$
DISCUSSION...23
AVIATION/MARINE...43
AREA FORECAST DISCUSSION
NWS BLACKSBURG VA
149 PM EDT TUE MAY 27 2014
.SYNOPSIS...
HIGH PRESSURE WILL CONTINUE TO STAY OFF THE SOUTHEAST COAST TODAY
AND TONIGHT. A BACKDOOR COLD FRONT ENTERS THE MID ATLANTIC REGION
WEDNESDAY...PUSHING SLOWLY SOUTH INTO THE CAROLINAS BY LATE
THURSDAY. HIGH PRESSURE WILL BUILD IN BEHIND THE FRONT AT THE END
OF THE WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 130 PM EDT TUESDAY...
CONVECTION MAKING TOWARD THE PIEDMONT THIS AFTERNOON WITH MAINLY
SCT COVERAGE. FORECAST ON TRACK IN TERMS OF THIS INTO THE LATE
AFTERNOON...SO NO CHANGES WERE MADE. SOME TEMPS ADJUSTED UP AND
DOWN BASED ON CONVECTION/CLOUD LOCATIONS...BUT OVERALL NOT MUCH
CHANGE THERE AS WELL.
PREVIOUS DISCUSSION...
VERY MOIST AIRMASS IN THE REGION WITH PWATS FROM 1.2 TO 1.5.
CLUSTER OF SHRA/ISOLATED TSRA FROM ERN KY INTO THE MTN EMPIRE OF
SW VA WILL CONTINUE TO SLOWLY TRACK EAST-SOUTHEAST THIS MORNING.
WEAK VORT DEPICTED PER LATEST RUC MESOANALYSIS OVER ERN WV WILL
TRACK SE INTO THE PIEDMONT BY MID AFTERNOON. NOT A LOT TO FOCUS ON
SPECIFICALLY IN TERMS OF AREAL COVERAGE OF SHOWERS AND STORMS THIS
AFTERNOON...SO GOING TO TRY TO DEPICT AT LEAST INTO MIDDAY THE
LATEST HRRR AND TO SOME EXTENT THE WRF THAT SHOWS CLUSTERS OF
SHOWERS AND STORMS OVER THE WEST AND SOUTHWEST...THEN COVERAGE
WILL BE MORE SCATTERED AND AT TIMES NUMEROUS THIS AFTERNOON AFTER
2-3 PM EVERYWHERE.
TEMPS ARE RUNNING WARMER IN THE EASTERN 2/3RDS OF THE CWA OUTSIDE
THE CLOUD COVER AND SHOWERS OVER THE SW. MADE SOME ADJUSTMENTS UP
TO ACCOUNT FOR THIS...BUT GIVEN CLOUDS WILL INCREASE AS WILL
SHOWERS...AND STORMS THREAT...WILL SEE TEMPS GET AFFECTED SOME
AFTER 2-3 PM. STILL LOOKS LIKE HIGHS AROUND 90 IN THE SOUTHEAST.
THE UPPER TROF WEAKENS THRU TONIGHT. PRECIPITATION MAY NOT
COMPLETELY DISSIPATE AFTER SUNSET THIS EVENING...BUT AREAL
COVERAGE WILL CERTAINLY BE REDUCED.
WITH FORECAST AREA REMAINING IN THE WARM SECTOR OVERNIGHT...MINIMUM
TEMPERATURES WILL STAY MILD. BLEND OF BIAS CORRECTED MAV/MET
GUIDANCE LOOKED REASONABLE.
&&
.SHORT TERM /WEDNESDAY THROUGH FRIDAY NIGHT/...
AS OF 330 AM EDT TUESDAY...
BACKDOOR FRONT WILL BE THE PRIMARY TRIGGER OF SHOWERS AND
THUNDERSTORMS...AS IT SLOWLY DROPS FROM NE TO SW WEDNESDAY AND
THURSDAY. TOUGH TO PINPOINT ONE AREA OVER ANOTHER FOR STORM
DEVELOPMENT...HOWEVER ALONG AND JUST TO THE WEST/EAST OF THE BLUE
RIDGE IS TYPICALLY FAVORED. RATHER WEAK FLOW COULD LEAD TO COLLIDING
OUTFLOWS AND/OR BACKBUILDING STORMS...AND HEAVY RAINFALL. THE GFS IS
THE ONLY MODEL WHICH HANGS THE FRONT CLOSE ENOUGH ON FRIDAY TO KEEP
STORMS IN THE FORECAST FOR THE SOUTHERN QUARTER OF THE CWA...WITH
POSSIBLY SOME SURFACE CONVERGENCE THROUGH NW NC. ALL OTHER MODELS
PLUNGE DRIER AND COOLER AIR FURTHER SOUTH WHICH SHUTS OFF STORMS
ACROSS THE ENTIRE REGION. TEMPS WILL BE TOUGH...HIGHLY DEPENDENT
UPON WHICH CITIES GET RAIN...AND THEN ON FRIDAY...HOW FAR SOUTH THE
COOLER MORE STABLE AIRMASS PENETRATES.
&&
.LONG TERM /SATURDAY THROUGH MONDAY/...
AS OF 345 PM EDT MONDAY...
MODELS INDICATING GREATER AMPLIFICATION OF THE UPPER FLOW THROUGH
THE LONG TERM THAN INDICATED YESTERDAY...RESULTING IN THE
AFOREMENTIONED BACKDOOR FRONT BEING PUSHED WELL SOUTH OF THE CWA
BY LATE FRI...WITH VERY DRY AIR POISED TO SPREAD SOUTHWARD INTO
THE REGION FROM THE NORTH FOR THE WEEKEND. FRONTAL/BAROCLINIC ZONE
ASSOCIATED SHRA/TSRA FRI WILL BE CONFINED TO THE WESTERN PART OF
THE FORECAST AREA...MAINLY WEST OF I-77 INTO THE NW NC MOUNTAINS.
HAVE GENERALLY DROPPED POPS FROM THE CWA FOR THE WEEKEND...EXCEPT
STILL SOME SMALL CHANCE THROUGH THE NW NC MOUNTAINS WHERE SLIGHTLY
BETTER INSTABILITY AND DIFFERENTIAL HEATING WILL BE PRESENT.
THE ECMWF IS SLIGHTLY QUICKER TO BREAK DOWN THE UPPER RIDGE TO
THE WEST OF THE REGION EARLY NEXT WEEK...ALLOWING THE NEXT
UPSTREAM WEATHER SYSTEM TO RESULT IN AN INCREASE IN SHRA/TSRA
ACTIVITY ACROSS THE ALLEGHANYS EARLY NEXT WEEK. FOR NOW...HAVE
KEPT POPS FOR MON-TUE FROM THE ALLEGHANYS WESTWARD.
NEAR NORMAL TEMPERATURES EXPECTED THROUGH THE PERIOD WITH
INCREASING AMOUNTS OF SUNSHINE AND DRY AIR OFFSETTING THE SLIGHTLY
COOLER AIR BEHIND THE FRONT. WARMER TEMPERATURES CAN BE EXPECTED
EARLY NEXT WEEK AS THE UPPER RIDGE AXIS DRIFTS SLOWLY EAST AND
850MB TEMPS WARM FROM +12C BACK TOWARD +16C BY MON/TUE. STILL NO
SIGNS OF ANY APPRECIABLE HOT WEATHER. MORNING TEMPS WILL BE COOLER
OVER THE WEEKEND OWING LARGELY TO THE DRIER AIR BEHIND THE
FRONT. SOME VERY PLEASANT MORNING LOWS IN THE 50S CAN BE EXPECTED.
&&
.AVIATION /18Z TUESDAY THROUGH SUNDAY/...
AS OF 130 PM EDT TUESDAY...
SCATTERED COVERAGE OF SHRA/TSRA TO STICK AROUND INTO EARLY
EVENING/01Z BEFORE DISSIPATING. LOOKS LIKELY THAT DAN/LWB WILL GET
A PERIOD OF TSRA BETWEEN 19-21Z. OTHERWISE VFR EXPECTED OUTSIDE OF
ANY STORMS...ALTHOUGH BLF CIGS STAYING MVFR TO EARLY EVENING.
TONIGHT...THE ISSUE WILL BE IF MID/HIGH CLOUDS IMPACT FOG
FORMATION OVERNIGHT. THINK THE CLOUD COVER WILL BE THERE...SO ONLY
TAKING LWB/BCB/LYH/DAN TO LOW END MVFR/HIGH END IFR LATE TONIGHT.
POSSIBILITY EXISTS GIVEN THE RAIN THIS AFTERNOON THAT LOWER VSBYS
NOT OUT OF THE QUESTION.
FOG GOING TO LIFT AFTER 12Z...TO BKN MID/HIGH CLOUDS WITH SCT/BKN
LOWER CU/SC INTO BLF/LWB...WHERE NEXT THREAT OF SHRA/TSRA ARRIVES
AFTER 14Z....BUT COVERAGE NOT HIGH ENOUGH TO HAVE THEM IN THE
PREDOMINATE GROUP...JUST VCTS.
THROUGH THURSDAY...THE WEATHER PATTERN FAVORS CHANCE FOR
AFTERNOON AND EVENING SHOWER AND THUNDERSTORMS...AND MVFR FOG
OVERNIGHT ESPECIALLY AT THE CLIMATOLOGICALLY FAVORED SITES SUCH AS
LWB/BCB/LYH. BEST COVERAGE OF SHOWERS AND THUNDERSTORMS WILL BE ON
THURSDAY WITH A COLD FRONT PUSHING THROUGH THROUGH THE AREA. THE
FRONT WILL BRING DRIER AIR AND VFR CONDITIONS BACK INTO THE REGION
FOR FRIDAY NIGHT AND SATURDAY.
&&
.RNK WATCHES/WARNINGS/ADVISORIES...
VA...NONE.
NC...NONE.
WV...NONE.
&&
$$
SYNOPSIS...AMS
NEAR TERM...AMS/WP
SHORT TERM...KM
LONG TERM...RAB
AVIATION...AMS/PM/WP
AREA FORECAST DISCUSSION
NWS BLACKSBURG VA
1029 AM EDT TUE MAY 27 2014
.SYNOPSIS...
HIGH PRESSURE WILL CONTINUE TO STAY OFF THE SOUTHEAST COAST TODAY
AND TONIGHT. A BACKDOOR COLD FRONT ENTERS THE MID ATLANTIC REGION
WEDNESDAY...PUSHING SLOWLY SOUTH INTO THE CAROLINAS BY LATE
THURSDAY. HIGH PRESSURE WILL BUILD IN BEHIND THE FRONT AT THE END
OF THE WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 1020 AM EDT TUESDAY...
VERY MOIST AIRMASS IN THE REGION WITH PWATS FROM 1.2 TO 1.5.
CLUSTER OF SHRA/ISOLATED TSRA FROM ERN KY INTO THE MTN EMPIRE OF
SW VA WILL CONTINUE TO SLOWLY TRACK EAST-SOUTHEAST THIS MORNING.
WEAK VORT DEPICTED PER LATEST RUC MESOANALYSIS OVER ERN WV WILL
TRACK SE INTO THE PIEDMONT BY MID AFTERNOON. NOT A LOT TO FOCUS ON
SPECIFICALLY IN TERMS OF AREAL COVERAGE OF SHOWERS AND STORMS THIS
AFTERNOON...SO GOING TO TRY TO DEPICT AT LEAST INTO MIDDAY THE
LATEST HRRR AND TO SOME EXTENT THE WRF THAT SHOWS CLUSTERS OF
SHOWERS AND STORMS OVER THE WEST AND SOUTHWEST...THEN COVERAGE
WILL BE MORE SCATTERED AND AT TIMES NUMEROUS THIS AFTERNOON AFTER
2-3 PM EVERYWHERE.
TEMPS ARE RUNNING WARMER IN THE EASTERN 2/3RDS OF THE CWA OUTSIDE
THE CLOUD COVER AND SHOWERS OVER THE SW. MADE SOME ADJUSTMENTS UP
TO ACCOUNT FOR THIS...BUT GIVEN CLOUDS WILL INCREASE AS WILL
SHOWERS...AND STORMS THREAT...WILL SEE TEMPS GET AFFECTED SOME
AFTER 2-3 PM. STILL LOOKS LIKE HIGHS AROUND 90 IN THE SOUTHEAST.
PREVIOUS VALID DISCUSSION...
AT THE SURFACE HIGH PRESSURE WAS WELL OFF THE SOUTHEAST COAST
WITH A WEAK TROF IN THE LEE OF THE APPALACHIANS THIS MORNING. THE
UPPER TROF WEAKENS THRU TONIGHT. PRECIPITATION MAY NOT
COMPLETELY DISSIPATE AFTER SUNSET THIS EVENING...BUT AREAL
COVERAGE WILL CERTAINLY BE REDUCED.
WITH FORECAST AREA REMAINING IN THE WARM SECTOR OVERNIGHT...MINIMUM
TEMPERATURES WILL STAY MILD. BLEND OF BIAS CORRECTED MAV/MET
GUIDANCE LOOKED REASONABLE.
&&
.SHORT TERM /WEDNESDAY THROUGH FRIDAY NIGHT/...
AS OF 330 AM EDT TUESDAY...
BACKDOOR FRONT WILL BE THE PRIMARY TRIGGER OF SHOWERS AND
THUNDERSTORMS...AS IT SLOWLY DROPS FROM NE TO SW WEDNESDAY AND
THURSDAY. TOUGH TO PINPOINT ONE AREA OVER ANOTHER FOR STORM
DEVELOPMENT...HOWEVER ALONG AND JUST TO THE WEST/EAST OF THE BLUE
RIDGE IS TYPICALLY FAVORED. RATHER WEAK FLOW COULD LEAD TO COLLIDING
OUTFLOWS AND/OR BACKBUILDING STORMS...AND HEAVY RAINFALL. THE GFS IS
THE ONLY MODEL WHICH HANGS THE FRONT CLOSE ENOUGH ON FRIDAY TO KEEP
STORMS IN THE FORECAST FOR THE SOUTHERN QUARTER OF THE CWA...WITH
POSSIBLY SOME SURFACE CONVERGENCE THROUGH NW NC. ALL OTHER MODELS
PLUNGE DRIER AND COOLER AIR FURTHER SOUTH WHICH SHUTS OFF STORMS
ACROSS THE ENTIRE REGION. TEMPS WILL BE TOUGH...HIGHLY DEPENDENT
UPON WHICH CITIES GET RAIN...AND THEN ON FRIDAY...HOW FAR SOUTH THE
COOLER MORE STABLE AIRMASS PENETRATES.
&&
.LONG TERM /SATURDAY THROUGH MONDAY/...
AS OF 345 PM EDT MONDAY...
MODELS INDICATING GREATER AMPLIFICATION OF THE UPPER FLOW THROUGH
THE LONG TERM THAN INDICATED YESTERDAY...RESULTING IN THE
AFOREMENTIONED BACKDOOR FRONT BEING PUSHED WELL SOUTH OF THE CWA
BY LATE FRI...WITH VERY DRY AIR POISED TO SPREAD SOUTHWARD INTO
THE REGION FROM THE NORTH FOR THE WEEKEND. FRONTAL/BAROCLINIC ZONE
ASSOCIATED SHRA/TSRA FRI WILL BE CONFINED TO THE WESTERN PART OF
THE FORECAST AREA...MAINLY WEST OF I-77 INTO THE NW NC MOUNTAINS.
HAVE GENERALLY DROPPED POPS FROM THE CWA FOR THE WEEKEND...EXCEPT
STILL SOME SMALL CHANCE THROUGH THE NW NC MOUNTAINS WHERE SLIGHTLY
BETTER INSTABILITY AND DIFFERENTIAL HEATING WILL BE PRESENT.
THE ECMWF IS SLIGHTLY QUICKER TO BREAK DOWN THE UPPER RIDGE TO
THE WEST OF THE REGION EARLY NEXT WEEK...ALLOWING THE NEXT
UPSTREAM WEATHER SYSTEM TO RESULT IN AN INCREASE IN SHRA/TSRA
ACTIVITY ACROSS THE ALLEGHANYS EARLY NEXT WEEK. FOR NOW...HAVE
KEPT POPS FOR MON-TUE FROM THE ALLEGHANYS WESTWARD.
NEAR NORMAL TEMPERATURES EXPECTED THROUGH THE PERIOD WITH
INCREASING AMOUNTS OF SUNSHINE AND DRY AIR OFFSETTING THE SLIGHTLY
COOLER AIR BEHIND THE FRONT. WARMER TEMPERATURES CAN BE EXPECTED
EARLY NEXT WEEK AS THE UPPER RIDGE AXIS DRIFTS SLOWLY EAST AND
850MB TEMPS WARM FROM +12C BACK TOWARD +16C BY MON/TUE. STILL NO
SIGNS OF ANY APPRECIABLE HOT WEATHER. MORNING TEMPS WILL BE COOLER
OVER THE WEEKEND OWING LARGELY TO THE DRIER AIR BEHIND THE
FRONT. SOME VERY PLEASANT MORNING LOWS IN THE 50S CAN BE EXPECTED.
&&
.AVIATION /15Z TUESDAY THROUGH SATURDAY/...
AS OF 720 AM EDT MONDAY...
CLUSTER OF SHOWERS AND THUNDERSTORMS IN EASTERN KENTUCKY WAS
MOVING SOUTHEAST AND WILL REACH KBLF AROUND 12Z/8AM...AND KBCB
AROUND 13Z/9AM. EXPECTING MVFR CEILINGS AT KBLF WITH THIS
PRECIPITATION.
HIGH CONFIDENCE OF SCATTERED SHOWERS AND THUNDERSTORMS ACROSS THE
REGION THIS AFTERNOON AND EVENING. LOW CONFIDENCE AS TO EXACTLY
WHERE STORMS WILL DEVELOP SO HAVE ONLY INCLUDED VCTS IN THE TAFS
FOR NOW. COVERAGE OF SHOWERS AND THUNDERSTORMS WILL DIMINISH...BUT
PROBABLY NOT COMPLETELY ERODE AFTER SUNSET. LOCATIONS THAT GET
RAIN THIS AFTERNOON...THEN CLEAR OUT OVERNIGHT WILL HAVE A HIGH
PROBABILITY OF MVFR TO IFR FOG AFTER MIDNIGHT.
THROUGH THURSDAY...THE WEATHER PATTERN FAVORS THE INCREASING
CHANCE FOR AFTERNOON AND EVENING SHOWER AND THUNDERSTORMS...AND
MVFR FOG OVERNIGHT ESPECIALLY AT THE CLIMATOLOGICALLY FAVORED
SITES SUCH AS LWB/BCB/LYH. BEST COVERAGE OF SHOWERS AND
THUNDERSTORMS WILL BE ON THURSDAY WITH A COLD FRONT PUSHING
THROUGH THROUGH THE AREA. THE FRONT WILL BRING DRIER AIR AND VFR
CONDITIONS BACK INTO THE REGION FOR FRIDAY NIGHT AND SATURDAY.
&&
.RNK WATCHES/WARNINGS/ADVISORIES...
VA...NONE.
NC...NONE.
WV...NONE.
&&
$$
SYNOPSIS...AMS
NEAR TERM...AMS/WP
SHORT TERM...KM
LONG TERM...RAB
AVIATION...AMS/PM
AREA FORECAST DISCUSSION
NWS BLACKSBURG VA
437 AM EDT TUE MAY 27 2014
.SYNOPSIS...
HIGH PRESSURE WILL CONTINUE TO STAY OFF THE SOUTHEAST COAST TODAY
AND TONIGHT. A BACKDOOR COLD FRONT ENTERS THE MID ATLANTIC REGION
WEDNESDAY...PUSHING SLOWLY SOUTH INTO THE CAROLINAS BY LATE
THURSDAY. HIGH PRESSURE WILL BUILD IN BEHIND THE FRONT AT THE END
OF THE WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 400 AM EDT TUESDAY...
AT THE SURFACE HIGH PRESSURE WAS WELL OFF THE SOUTHEAST COAST WITH A
WEAK TROF IN THE LEE OF THE APPALACHIANS. THE UPPER TROF WEAKENS
TODAY AND TONIGHT. LEE TROF AND POSSIBLY OUTFLOW FROM THE MORE
ORGANIZED SHOWERS AND THUNDERSTORMS ACROSS THE OHIO VALLEY THROUGH
SOUTHERN PENNSYLVANIA WILL BE THE MORE FAVORABLE LOCATIONS FOR
SCATTERED THUNDERSTORM DEVELOPMENT THIS AFTERNOON. THERE WILL BE
LITTLE TO NO UPPER SUPPORT OR SHORT WAVE ENERGY TO NARROW DOWN MORE
LIKELY LOCATION OR TIMING FOR STORMS. ALSO...06Z HRRR HAD ISOLATED
SHOWERS AND THUNDERSTORMS MOVING INTO THE MOUNTAIN EMPIRE REGION
AFTER 10Z/6AM. THIS MAY BE PICKING UP ON THE SHOWERS AND
THUNDERSTORMS THAT WERE DEVELOPING IN NORTH CENTRAL KENTUCKY AT
4AM. PRECIPITATION MAY NOT COMPLETELY DISSIPATE AFTER SUNSET
THIS EVENING...BUT AREAL COVERAGE WILL CERTAINLY BE REDUCED.
MOST LOCATIONS IN THE MID 50S TO MID 60S THIS MORNING. STAYED CLOSER
TO WARMER MAV GUIDANCE FOR MAXIMUM TEMPERATURES...BUT THIS WILL BE
HIGHLY DEPENDENT ON HOW FAST CLOUD COVER FILLS IN THIS MORNING.
WITH FORECAST AREA REMAINING IN THE WARM SECTOR OVERNIGHT...MINIMUM
TEMPERATURES WILL STAY MILD. BLEND OF BIAS CORRECTED MAV/MET
GUIDANCE LOOKED REASONABLE.
&&
.SHORT TERM /WEDNESDAY THROUGH FRIDAY NIGHT/...
AS OF 330 AM EDT TUESDAY...
BACKDOOR FRONT WILL BE THE PRIMARY TRIGGER OF SHOWERS AND
THUNDERSTORMS...AS IT SLOWLY DROPS FROM NE TO SW WEDNESDAY AND
THURSDAY. TOUGH TO PINPOINT ONE AREA OVER ANOTHER FOR STORM
DEVELOPMENT...HOWEVER ALONG AND JUST TO THE WEST/EAST OF THE BLUE
RIDGE IS TYPICALLY FAVORED. RATHER WEAK FLOW COULD LEAD TO COLLIDING
OUTFLOWS AND/OR BACKBUILDING STORMS...AND HEAVY RAINFALL. THE GFS IS
THE ONLY MODEL WHICH HANGS THE FRONT CLOSE ENOUGH ON FRIDAY TO KEEP
STORMS IN THE FORECAST FOR THE SOUTHERN QUARTER OF THE CWA...WITH
POSSIBLY SOME SURFACE CONVERGENCE THROUGH NW NC. ALL OTHER MODELS
PLUNGE DRIER AND COOLER AIR FURTHER SOUTH WHICH SHUTS OFF STORMS
ACROSS THE ENTIRE REGION. TEMPS WILL BE TOUGH...HIGHLY DEPENDENT
UPON WHICH CITIES GET RAIN...AND THEN ON FRIDAY...HOW FAR SOUTH THE
COOLER MORE STABLE AIRMASS PENETRATES.
&&
.LONG TERM /SATURDAY THROUGH MONDAY/...
AS OF 345 PM EDT MONDAY...
MODELS INDICATING GREATER AMPLIFICATION OF THE UPPER FLOW THROUGH
THE LONG TERM THAN INDICATED YESTERDAY...RESULTING IN THE
AFOREMENTIONED BACKDOOR FRONT BEING PUSHED WELL SOUTH OF THE CWA
BY LATE FRI...WITH VERY DRY AIR POISED TO SPREAD SOUTHWARD INTO
THE REGION FROM THE NORTH FOR THE WEEKEND. FRONTAL/BAROCLINIC ZONE
ASSOCIATED SHRA/TSRA FRI WILL BE CONFINED TO THE WESTERN PART OF
THE FORECAST AREA...MAINLY WEST OF I-77 INTO THE NW NC MOUNTAINS.
HAVE GENERALLY DROPPED POPS FROM THE CWA FOR THE WEEKEND...EXCEPT
STILL SOME SMALL CHANCE THROUGH THE NW NC MOUNTAINS WHERE SLIGHTLY
BETTER INSTABILITY AND DIFFERENTIAL HEATING WILL BE PRESENT.
THE ECMWF IS SLIGHTLY QUICKER TO BREAK DOWN THE UPPER RIDGE TO
THE WEST OF THE REGION EARLY NEXT WEEK...ALLOWING THE NEXT
UPSTREAM WEATHER SYSTEM TO RESULT IN AN INCREASE IN SHRA/TSRA
ACTIVITY ACROSS THE ALLEGHANYS EARLY NEXT WEEK. FOR NOW...HAVE
KEPT POPS FOR MON-TUE FROM THE ALLEGHANYS WESTWARD.
NEAR NORMAL TEMPERATURES EXPECTED THROUGH THE PERIOD WITH
INCREASING AMOUNTS OF SUNSHINE AND DRY AIR OFFSETTING THE SLIGHTLY
COOLER AIR BEHIND THE FRONT. WARMER TEMPERATURES CAN BE EXPECTED
EARLY NEXT WEEK AS THE UPPER RIDGE AXIS DRIFTS SLOWLY EAST AND
850MB TEMPS WARM FROM +12C BACK TOWARD +16C BY MON/TUE. STILL NO
SIGNS OF ANY APPRECIABLE HOT WEATHER. MORNING TEMPS WILL BE COOLER
OVER THE WEEKEND OWING LARGELY TO THE DRIER AIR BEHIND THE
FRONT. SOME VERY PLEASANT MORNING LOWS IN THE 50S CAN BE EXPECTED.
&&
.AVIATION /09Z TUESDAY THROUGH SATURDAY/...
AS OF 140 AM EDT MONDAY...
RADAR SHOWED SMALL...ISOLATED SHOWERS IN SOUTHEAST WEST VIRGINIA
EARLY THIS MORNING. DO NOT EXPECT MUCH CHANGE IN THIS PATTERN
THROUGH 12Z/8AM SO IT IS POSSIBLE A SHOWER COULD BE IN THE
VICINITY OF THE KBLF OR KLWB AIRPORT. PATCHY MVFR FOG WILL ALSO
DEVELOP ACROSS THE REGION...ESPECIALLY IN NORTHWEST NORTH CAROLINA
WHERE THERE WAS RAIN MONDAY AFTERNOON. ANY FOG WILL BURN OFF BY
13Z/9AM THIS MORNING.
HIGH CONFIDENCE OF SCATTERED TO BROKEN VFR CUMULUS DEVELOPMENT
THIS AFTERNOON ALONG WITH SCATTERED SHOWERS AND THUNDERSTORMS. LOW
CONFIDENCE AS TO EXACTLY WHERE STORMS WILL DEVELOP BUT KLWB AND
KBLF ARE THE AIRPORTS MOST LIKELY TO BE IMPACTED WITH MVFR
CONDITIONS DUE TO THE STORMS.
THROUGH MUCH OF THE WEEK...THE WEATHER PATTERN FAVORS THE
INCREASING CHANCE FOR AFTERNOON AND EVENING SHOWER AND
THUNDERSTORMS...AND MVFR FOG OVERNIGHT ESPECIALLY AT THE
CLIMATOLOGICALLY FAVORED SITES SUCH AS LWB/BCB/LYH. BEST COVERAGE
OF SHOWERS AND THUNDERSTORMS WILL BE ON THURSDAY WITH A COLD FRONT
PUSHING THROUGH THROUGH THE AREA. THE FRONT WILL BRING DRIER AIR
AND VFR CONDITIONS BACK INTO THE REGION FOR FRIDAY NIGHT AND
SATURDAY.
&&
.RNK WATCHES/WARNINGS/ADVISORIES...
VA...NONE.
NC...NONE.
WV...NONE.
&&
$$
SYNOPSIS...AMS
NEAR TERM...AMS
SHORT TERM...KM
LONG TERM...RAB
AVIATION...AMS/PM
AREA FORECAST DISCUSSION...UPDATED
NWS MILWAUKEE/SULLIVAN WI
930 PM CDT WED MAY 28 2014
.UPDATE...
SHORT WAVE HAS SETTLED FAR ENOUGH TO THE SOUTH...AND ALONG WITH
NOCTURNAL STABILIZATION...HAS ALLOWED SKIES TO CLEAR OVER SRN WI.
LOBE OF SURFACE HIGH PRESSURE THAT BUILT DOWN OVER THE LAKE THIS
AFTERNOON HAS EXPANDED TO WEAKEN GRADIENT OVER THE FAR SE AND
REDUCE WIND GUSTS THAT REACHED 22-25 KNOTS FROM MILWAUKEE SOUTH
INTO NE IL LATE THIS AFTERNOON INTO THE EARLY EVENING. 925 MB
PROFILER WINDS NEVER EXCEEDED 15 KNOTS...SO IT APPEARS GRADIENT
WINDS WERE AIDED BY DENSITY DISCONTINUITY BETWEEN THE COLDER LAKE
AIR AND THE WARMER INLAND AIR MASS. EXCEPT FOR SOME MINOR TWEAKS
TO SKY AND TEMPERATURES GOING FORECAST LOOKS GOOD.
&&
.AVIATION/06Z TAFS/...
LOOKING AT VFR CONDITIONS THROUGH THE FORECAST. WILL AWAIT THE
REST OF THE 00Z DATA...BUT APPEARS 00Z NAM MET MOS GUIDANCE AND
PREVIOUS GFS MAV ARE TOO HIGH WITH SFC DEW POINTS...LEADING TO
MVFR VSBY IN FOG/HAZE AND VFR CIGS IN OUTPUT OVERNIGHT. COULD SEE
SOME PATCHY FOG...BUT CHANCE APPEARS TOO LOW TO MENTION IN
FORECAST.
&&
.PREV DISCUSSION... /ISSUED 236 PM CDT WED MAY 28 2014/
SHORT TERM...TONIGHT AND THURSDAY.
LATEST RUC ANALYSIS AND SATELLITE/RADAR IMAGERY SHOW SEVERAL
SHORTWAVE TROUGHS MOVING SLOWLY SOUTHEAST OVER THE SOUTHERN
WISCONSIN...NORTHERN ILLINOIS...AND EASTERN IOWA REGION. A SURFACE
COLD FRONT LIES FROM SOUTHERN IOWA TO NORTHERN INDIANA AND MARKS
THE TRANSITION FROM A HUMID SUMMER AIRMASS AND A MUCH COOLER/DRIER
CANADIAN AIRMASS. A FEW LIGHT SHOWERS AND SPRINKLE CONTINUE TO
SHOW UP ON AREA RADARS EARLY THIS AFTERNOON OVER SOUTH-CENTRAL AND
SOUTHEAST WISCONSIN WHERE MID-LEVEL MOISTURE HAS YET TO DEPART...BUT
THE DEEPER CONVECTION RESIDES CLOSER TO THE FRONT JUST SOUTH OF
THE INTERSTATE 80 CORRIDOR. THE BACK EDGE OF THE MID-LEVEL CLOUD
DECK CONTINUES TO GRADUALLY DROP SOUTHWARD OVER CENTRAL AND
NORTHERN WISCONSIN. FORECAST CONCERNS INCLUDE LIGHT SHOWER AND
CLOUD TRENDS FOLLOWED BY TEMPS.
TONIGHT...SHORTWAVE TROUGHING OVER THE WESTERN GREAT LAKES WILL
SLIDE GRADUALLY SOUTHWARD AND WEAKEN AT THE SAME TIME. SCATTERED
TO BROKEN MID-LEVEL CLOUDS WILL BE LINGERING AT LEAST ALONG AND
SOUTH OF INTERSTATE 94 AT THE START OF THE EVENING IF NOT A LITTLE
FARTHER NORTH...BUT WILL END THE LIGHT SHOWER OR SPRINKLE CHANCE
AT THE START OF THE PERIOD. THEN WILL SEE A SLOW DECREASING CLOUD
TREND FROM NORTH TO SOUTH OVER THE COURSE OF THE NIGHT. IT WILL BE
A COOLER AND LESS HUMID NIGHT WITH TEMPS RANGING FROM THE MID 40S
TO MID 50S.
THURSDAY...HUDSON BAY HIGH PRESSURE WILL BUILD SOUTHWARD OVER THE
CENTRAL GREAT LAKES. NORTHEAST WINDS ORIGINATING OUT OF THIS HIGH
WILL ADVECT A DRY AIRMASS INTO THE REGION. SHOULD SEE PLENTY OF
SUNSHINE WITH HIGHS RANGING THROUGH THE 70S EXCEPT NEAR LAKE
MICHIGAN.
LONG TERM...THURSDAY NIGHT THROUGH NEXT WEDNESDAY.
THURSDAY NIGHT THROUGH SATURDAY...THE HIGH PRESSURE SYSTEM WILL BE
HANGING AROUND THE REGION THROUGH FRIDAY NIGHT...THEN BEGIN TO
DEPART TO THE EAST ON SATURDAY. AS A RESULT...SHOULD SEE MOSTLY CLEAR AND
PLEASANT CONDITIONS OVER THE PERIOD. TEMPERATURES WILL WARM A
DEGREE OR TWO ON BOTH FRIDAY AND SATURDAY. LOWS MAINLY IN THE
50S.
REST OF THE FORECAST...A CHANGE OF AIRMASS WILL OCCUR SATURDAY
NIGHT INTO SUNDAY WHEN A WARM FRONT MOVES EAST ACROSS THE REGION.
PWATS WILL INCREASE UPWARDS OF 1.50 TO 1.75 INCHES AND WILL HAVE
WEAK SHORTWAVE ENERGY TRAVERSING THE NORTHERN MISSISSIPPI VALLEY.
SHOWER AND THUNDERSTORM CHANCES WILL IMPROVE SATURDAY NIGHT OVER
THE WESTERN FORECAST AREA AND ON SUNDAY ACROSS EAST. WILL LIKELY
SEE A LARGE DIURNAL COMPONENT TO THE CONVECTION SINCE FORCING
ALOFT IS RELATIVELY WEAK. THE THREAT OF STORMS WILL CONTINUE
THROUGH TUESDAY WHEN A COLD FRONT MOVES ACROSS THE REGION. LIKE
THE PREVIOUS FORECASTER MENTIONED...THE THREAT OF SEVERE STORMS IS
ON THE LOW SIDE DUE TO WEAK WIND FIELDS ALOFT ON SUNDAY AND
MONDAY...BUT COULD IMPROVE AHEAD OF THE COLD FRONT HEADING INTO
TUESDAY.
MARINE...NORTHEAST WINDS WILL DIMINISH LATE TONIGHT AND LEAD TO
SUBSIDING WAVES. LIGHT NORTHEAST FLOW WILL THEN CONTINUE INTO
FRIDAY.
&&
.MKX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
LM...NONE.
&&
$$
UPDATE...REM
TONIGHT/THURSDAY AND AVIATION/MARINE...MPC
THURSDAY NIGHT THROUGH WEDNESDAY...MPC
FORECAST DISCUSSION FOR ROUTINE AFTERNOON FORECAST ISSUANCE
.SHORT TERM...TONIGHT AND WEDNESDAY
ISSUED AT 315 PM CDT TUE MAY 27 2014
THE LATEST RUC ANALYSIS AND SATELLITE/RADAR IMAGERY SHOW A WEAK
SURFACE COLD FRONT STRETCHING FROM SOUTHERN MINNESOTA TO SOUTHERN
WISCONSIN EARLY THIS AFTERNOON. OVER WESTERN WISCONSIN AND EASTERN
MINNESOTA IS SHORTWAVE THAT IS VERY SLOWLY SLIDING SOUTHEAST.
DESPITE BEING LOCATED NORTH OF THE COLD FRONT...THE ATMOSPHERE
REMAINS VERY MOIST THROUGH THE COLUMN OVER CENTRAL AND EAST-CENTRAL
WISCONSIN WHERE RAIN SHOWERS HAVE BEEN THE MOST PERSISTENT. THE
AREA SOUTH OF WISCONSIN RAPIDS AND WAUTOMA ARE BEGINNING TO
DESTABILIZE THIS AFTERNOON...AFTER THE RAIN LIFTED OFF TO THEIR
NORTH. SOME POTENTIAL FOR ADDITIONAL SHOWER AND STORM DEVELOPMENT
IN THIS AREA FOR THE REST OF THE AFTERNOON. OTHERWISE...MAINLY
LOOKING AT SCATTERED SHOWERS MOSTLY SOUTH OF A MERRILL TO MANITOWOC
LINE THROUGH EARLY THIS EVENING. MUCH DRIER AIR RESIDES OVER THE
UPPER PENINSULA AND LAKE SUPERIOR...AND LIGHT NORTHEAST WINDS WILL
CONTINUE TO ERODE ANY SHOWER ACTIVITY AS IT TRIES TO LIFT
NORTHWARD. PRECIP CHANCES REMAIN THE MAIN FORECAST CONCERN IN THE
SHORT TERM...FOLLOWED BY TEMPS.
TONIGHT...THE SHORTWAVE TROUGH SPINNING OVER SOUTHEAST MINNESOTA AND
WESTERN WISCONSIN IS PROJECTED TO SLIDE SOUTHEAST TONIGHT WHILE THE
WEAK COOL FRONT SHIFTS SOUTH ACROSS FAR SOUTHERN WISCONSIN AND
NORTHERN ILLINOIS. MID-LEVEL CONVERGENCE AND MOISTURE AXIS WILL
SHIFT SOUTH WITH THESE FEATURES...BUT THINK THE PROXIMITY OF THE
SHORTWAVE AND PWATS UPWARDS OF 1.5 INCHES WILL KEEP A CHANCE OF
SHOWERS GOING OVER CENTRAL WISCONSIN AND THE FOX VALLEY THROUGH LATE
IN THE EVENING. MEANWHILE...VERY DRY AIR OVER THE LAKE SUPERIOR
REGION WILL BE SURGING SOUTHWARD INTO NORTH-CENTRAL AND NORTHEAST
WISCONSIN BY LATE IN THE EVENING AND THE REST OF THE REGION BY
WEDNESDAY MORNING. AS A RESULT...SHOULD SEE A SLOW DECREASING CLOUD
TREND OVER THE COURSE OF THE NIGHT. THE INFLUX OF DRIER AIR AND
DIMINISHING CLOUDS WILL LEAD TO A MUCH COOLER AND LESS HUMID NIGHT.
LOWS FROM THE MID 40S NORTH TO MID 50S SOUTH.
WEDNESDAY...ANY LINGERING MID AND HIGH LEVEL CLOUDS WILL GRADUALLY
DEPART CENTRAL AND EAST-CENTRAL WISCONSIN AS A VERY DRY AIRMASS FROM
A HUDSON BAY HIGH DRIFTS INTO THE REGION. WITH PLENTY OF
SUNSHINE...TEMPS SHOULD REACH THE MIDDLE 70S TO LOWER 80S WEST OF
THE FOX VALLEY AND BAY OF GREEN BAY WHERE LIGHT EAST WINDS WILL
KEEPS HIGHS COMPARATIVELY COOLER.
.LONG TERM...WEDNESDAY NIGHT THROUGH TUESDAY
ISSUED AT 315 PM CDT TUE MAY 27 2014
HIGH PRESSURE ANCHORED OVER THE REGION LATER THIS WEEK WILL
PROVIDE VERY PLEASANT WEATHER FOR THE REMAINDER OF MAY. THE WEATHER
PATTERN WILL THEN TURN A BIT MORE ACTIVE FOR THE START OF JUNE.
UPPER RIDGE WITH SURFACE HIGH PRESSURE TO PRODUCE PLENTY OF SUNSHINE
AND MILD DAYS THROUGH SATURDAY...WITH THE EXCEPTION OF THE COOLER
READINGS ALONG LAKE MICH AND THE BAY WITH THE PERSISTENT EASTERLY
WIND. THE DRIER AIR MASS UNDER CLEAR SKIES WILL LIKELY CREATE SOME
LARGE RANGES IN MIN TEMPS OVERNIGHT AS WELL.
FOR THE NEXT FRONTAL SYSTEM FOR THIS WEEKEND...24 HOUR TRENDS
HAVE INDICATED A SLOW DOWN. THE GEM WAS THE QUICKEST WITH
PRODUCING SOME QPF OVER THE WEST HALF OF THE STATE INCLUDING PARTS
OF CENTRAL WISCONSIN SATURDAY AFTERNOON. THE ECMWF AND GEM WERE MORE
PROGRESSIVE WITH THE FRONT WORKING INTO THE AREA ON SUNDAY WHILE
THE GFS KEEPS THE FRONT AND PRECIPITATION MAINLY NORTHWEST OF THE
AREA FOR MOST OF SUNDAY. THESE TIMING ISSUES MAGNIFY INTO EARLY
NEXT WEEK WITH THE ECMWF DROPPING THE FRONT SOUTH OF THE AREA
TOWARD MONDAY WHILE THE SLOWER GFS SUPPORTS MORE PRECIPITATION.
BLEND OF THE RUNS THEN INDICATE THE FRONT WILL RETURN NORTH AGAIN
WITH DEVELOPING SOUTHWEST FLOW ALOFT AHEAD OF AN NORTHERN PLAINS
TROUGH.
&&
.AVIATION...FOR 18Z TAF ISSUANCE
ISSUED AT 1236 PM CDT TUE MAY 27 2014
AN UPPER LEVEL DISTURBANCE WILL PRODUCE SCATTERED SHOWERS
AND THUNDERSTORMS TODAY. THE GREATEST AMOUNT OF ACTIVITY SHOULD BE
SOUTH OF A MERRILL TO MANITOWOC LINE. MVFR AND OCCASIONAL IFR
CONDITIONS ARE LIKELY WHERE THE SHOWERS OCCUR. THE SHOWERS WILL
DISSIPATE THIS EVENING WITH VFR CONDITIONS OVER ALL OF THE REGION
LATE TONIGHT THROUGH WEDNESDAY.
&&
.GRB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM.....MPC
LONG TERM......TDH
AVIATION.......MPC
AREA FORECAST DISCUSSION
NWS MILWAUKEE/SULLIVAN WI
231 PM CDT TUE MAY 27 2014
.TONIGHT - CONFIDENCE...MEDIUM
FRONTAL BOUNDARY BEING GIVEN EXTRA PUSH IN ERN WI DUE TO CONVECTIVE
OUTFLOWS AND THE COLDER LAKE WATERS. BOUNDARY LINED UP MORE OR LESS
FROM THE FAR SE CORNER OF THE CWA EXTENDING NW TOWARDS THE DELLS. VERY
LITTLE WIND UPSTAIRS WITH UPPER FLOW NOT DOING MUCH. MID LEVEL
LAPSE RATES NOT IMPRESSIVE AND NEITHER IS 0-6KM SHEAR. PLENTY OF WATER
IN THE COLUMN WITH PRECIPITABLE WATER VALUES RUNNING AROUND 1.6 PER SPC
MESO PAGE. CORFIDI VECTORS ARE LIGHT AND CURVED SO MAIN CONCERN IS POCKETS
OF HEAVIER RAINFALL INTO THE EVENING HOURS. 4KM SPC WRF SUGGESTING A
FAIRLY RAPID DROPOFF IN ACTIVITY THIS EVENING WHILE THE HRRR IS LENDING
CREDENCE TO THE WEAK SUPPORT FROM RELATIVELY WEAK MID LEVEL CIRCULATION
IN SRN MN. THIS SOLUTION KEEPS STORMS GOING MUCH LATER IN THE EVENING
ACROSS THE CWA. AS THE NIGHT PROGRESSES LOSS OF HEATING AND A GRADUAL
SOUTHWESTWARD SINKING OF THE BOUNDARY RESULTS IN A LOWERING OF POPS AND
TRENDING THE POPS SW WITH TIME. HOWEVER GIVEN HELP OF SOME WEAK PIVA INTO
WRN WI ASSOC WITH MID LEVEL SHORTWAVE...DECIDED TO LINGER POPS LONGER THAN
MY ORIGINAL THOUGHTS. ISODROSOTHERM ANALYSIS SHOWS THE DRIER AIR STARTING
TO WORK IN FROM THE NE.
.WEDNESDAY - CONFIDENCE...MEDIUM
MODELS TO VARYING DEGREES LINGER PRECIP IN THE SOUTHERN CWA DURING THE
MORNING IN CLOSER PROXIMITY TO LINGERING FORCING WITH SURFACE BOUNDARY.
WILL CARRY SOME POPS THERE TO ACCOUNT FOR THIS...BUT THEN GO DRY IN THE
AFTERNOON CWA WIDE WITH DRIER AND MORE STABLE INFLUENCE OF THE APPROACHING
HIGH TAKING HOLD.
.WEDENSDAY THROUGH SATURDAY...FORECAST CONFIDENCE IS HIGH.
A VERY QUIET...VERY PLEASANT STRETCH IS EXPECTED FOR THE LAST
HALF OF THE WEEK. CANADIAN HIGH PRESSURE WILL SETTLE OVER THE
CENTRAL GREAT LAKES KEEPING A PERSISTENT LIGHT EAST TO SOUTHEAST
FLOW ACROSS THE AREA. THE FLOW SHOULD BE LIGHT ENOUGH TO KEEP THE
LAKE MICHIGAN COOLING MACHINE LIMITED TO THE FAR EASTERN AREAS.
HIGHS WILL GENERALLY HIT THE MID 70S TO AROUND 80 WITH LOWS AT
NIGHT FALLING INTO THE UPPER 40S TO LOWER 50S...BUT THOSE LOWS
WILL MODIFY THROUGH THE END OF THE WEEK. TEMPERATURES WILL BE
COOLER NEAR THE LAKE OF COURSE.
.SUNDAY THROUGH TUESDAY...FORECAST CONFIDENCE IS MEDIUM.
A SOMEWHAT COMPLEX SCENARIO TAKES SHAPE FOR EARLY NEXT WEEK. THE
GFS AND THE ECMWF ARE STILL TRYING TO WORK OUT THEIR DIFFERENCES.
IN GENERAL...IT APPEARS LOW PRESSURE WILL TRACK TO THE NORTH OF
THE AREA SATURDAY NIGHT...ALLOWING A COLD FRONT/TROF TO DROP SOUTH
INTO THE AREA ON SUNDAY. THE FRONT WILL THEN STALL IN THE AREA
BEFORE LIFTING BACK NORTH AS ANOTHER LOW PRESSURE SYSTEM MOVES IN
FROM THE CENTRAL PLAINS. THIS WILL LIKELY RESULT IN A FAIRLY
ACTIVE PERIOD WITH ROUNDS OF THUNDERSTORMS. HOW THIS ALL EVOLVES
AND THE TIMING IS BEING HANDLED DIFFERENTLY BY THE GFS/ECMWF.
BUT...THE SIMILAR MESSAGE IS THAT IT WILL BE UNSETTLED WITHIN A
WARM AND HUMID AIRMASS.
&&
.AVIATION/00Z TAFS/...MAIN CONCERN WILL BE CONVECTIVE TRENDS INTO
THE EVENING HOURS WITH SOUTHWARD SAGGING FRONTAL BOUNDARY AND
LINGERING DAYTIME INSTABILITY. BRIEF HEAVY RAINS AND SMALL HAIL THE
PRIMARY CONCERNS. 4KM WRF AND HRRR SEEM TO HAVE A HANDLE ON THINGS. WILL
LINGER SOME SHRA/TSRA INTO THE EVENING WITH SOME HELP FROM WEAK MID LEVEL
TROUGH AXIS ACRS MN/IA. SURFACE HIGH GRADUALLY BUILDING IN FROM THE NORTH
THROUGH WEDNESDAY SO EXPECT A DRYER DAY.
&&
.MKX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
LM...NONE.
&&
$$
TONIGHT/WEDNESDAY AND AVIATION/MARINE...COLLAR
WEDNESDAY NIGHT THROUGH TUESDAY...DAVIS
AREA FORECAST DISCUSSION
NWS MILWAUKEE/SULLIVAN WI
1020 AM CDT TUE MAY 27 2014
.UPDATE...DECIDED TO SCALE BACK POPS FOR A WHILE TO ACCOUNT FOR
ONGOING DRYING TREND IN SRN WI. POCKET OF HIGHER CIN IN THE SW
CWA WITH ANY FOCUS FURTHER NE JUST NORTH OF SFC BOUNDARY SAGGING
SOUTHWARD. STILL EXPECT ADDITIONAL CONVECTION TO FIRE UP THIS
AFTERNOON PER TRENDS IN HRRR/4KM SPC WRF.
PC
&&
.AVIATION/18Z TAFS/...MAIN CONCERN WILL BE CONVECTIVE TRENDS THIS
AFTERNOON. EXPECT STORMS TO DEVELOP IN A SIMILAR FASHION TO
YESTERDAY PRODUCING BRIEF HEAVY RAINS AND MAINLY SMALL HAIL. 4KM
WRF AND HRRR SEEM TO HAVE A HANDLE ON THINGS WITH A QUIET PERIOD
INTO EARLY AFTERNOON. SURFACE HIGH GRADUALLY BUILDING IN FROM THE
NORTH THROUGH WEDNESDAY SO EXPECT A DRYER DAY.
PC
&&
.MARINE...DECIDED TO EXTEND DENSE FOG ADVISORY THROUGH AT LEAST
18Z PER SHEBOYGAN/PORT WASHINGTON WEBCAMS.
PC
&&
.PREV DISCUSSION... /ISSUED 329 AM CDT TUE MAY 27 2014/
TODAY AND TONIGHT...FORECAST CONFIDENCE IS HIGH.
THE MAIN 250 MB JET IS ACROSS SOUTHERN CANADA WITH A WEAK TROUGH
FROM MINNESOTA TO NORTHERN TEXAS. THE WEAK TROUGH MOVES INTO
WISCONSIN TONIGHT. THE UPPER FLOW IS WEAK WITH WEAK 250 MB
DIVERGENCE ACROSS SOUTHERN WISCONSIN. THE WEAK 500 MB TROUGH ACROSS
IOWA AND SOUTHERN MINNESOTA PUSHES INTO SOUTHERN WISCONSIN THIS
EVENING. 925/850/700/500 MB ARE MOIST WITH PRECIPITABLE WATER
VALUES AROUND 1.5 INCHES. 700 AND 850 MB WINDS ALSO WEAKEN TO 10
KNOTS OR LESS AS THE LOWER LEVEL TROUGH ARRIVES.
FORECAST SOUNDINGS HAVE ZERO TO 1 KM MIXED LAYER CAPES AROUND 500
JOULES/KG BY AFTERNOON WITH LITTLE OR NO CAP. THEREFORE EXPECT
ANOTHER DAY OF DIURUNALLY DRIVEN MOIST CONVECTION...WITH AN ADDED
FOCUS ON THE WEAK COLD FRONT SAGGING SOUTH AND APPROACHING TROUGH
FROM THE WEST.
WITH THE WEAK WINDS AND SLOW MOVEMENT...ANY OF THE THUNDERSTORMS
COULD PRODUCE LOCALLY HEAVY RAINFALL. SEVERE HAIL PARAMETERS ARE
LOW...BUT ISOLATED PULSE WET MICROBURSTS/HAIL ARE POSSIBLE WITH THE
STRONGER STORMS.
AREAS OF FOG ARE EXPECTED TO FORM EARLY THIS MORNING...AS WINDS
WEAKEN AND HUMID CONDITIONS LINGER. ANY FOG/LOW STRATUS SHOULD
DISSIPATE WITH DAYTIME HEATING.
WEDNESDAY...FORECAST CONFIDENCE...MEDIUM
MODELS DIFFER WITH THE PLACEMENT OF DEEP MOISTURE AND THE LOW/MID
LEVEL FRONTAL BOUNDARY WEDNESDAY MORNING. THE NORTHERN GEM/NAM
SOLUTIONS KEEP A CHANCE OF SHOWERS/STORMS THROUGH THE MORNING AND
INTO AT LEAST EARLY AFTERNOON. THE FARTHER SOUTH GFS/ECMWF SUGGEST
DRY WEATHER AS HIGH PRESSURE BUILDS IN FASTER FROM THE NORTH.
WENT WITH A CONSENSUS APPROACH FOR POPS...RESULTING IN A LOW
CHANCE MAINLY ACROSS THE SOUTH. SHOULD SEE TEMPS NEAR TO A FEW
DEGREES ABOVE NORMAL AWAY FROM LAKE MICHIGAN...WITH EAST WINDS
RESULTING IN NEAR TO BELOW NORMAL TEMPS NEAR THE LAKE.
THURSDAY THROUGH SATURDAY...FORECAST CONFIDENCE...HIGH
HIGH PRESSURE OVER THE GREAT LAKES WILL RESULT IN VERY PLEASANT
WEATHER FROM THURSDAY THROUGH SATURDAY. EXPECT PLENTY OF SUNSHINE
EACH DAY...WITH TEMPERATURES REMAINING ABOVE NORMAL MOST
PLACES. COOLER TEMPERATURES ARE LIKELY NEAR LAKE MICHIGAN THOUGH
AS ONSHORE WINDS WILL BE PERSISTENT THROUGH THIS PERIOD.
SUNDAY AND MONDAY...FORECAST CONFIDENCE...MEDIUM
MODELS ARE IN DECENT AGREEMENT THAT A CHANCE FOR SHOWERS AND
STORMS WILL RETURN EARLY NEXT WEEK AS HIGH PRESSURE HEADS
EASTWARD. WARM TEMPERATURES WILL LIKELY ALSO CONTINUE.
AVIATION/00Z TAFS/...
THE LIGHT WINDS AND MOIST AIRMASS WILL LEAD TO IFR/MVFR FOG
FORMATION AND POSSIBLE LOW STRATUS DEVELOPMENT THAT WILL LINGER INTO
MID MORNING.
ANY FOG/LOW STRATUS SHOULD DISSIPATE WITH HEATING. EXPECT ANOTHER
DAY OF DIURUNALLY DRIVEN MOIST CONVECTION. WITH THE WEAK WINDS AND
SLOW MOVEMENT...ANY OF THE THUNDERSTORMS COULD PRODUCE LOCALLY HEAVY
RAINFALL. SEVERE HAIL PARAMETERS ARE LOW...BUT ISOLATED WET
MICROBURSTS ARE POSSIBLE.
MARINE...
HIGH DEW POINTS MOVING OVER THE COLD LAKE MICHIGAN WATERS WILL BRING
AREAS OF DENSE FOG TO THE NEARSHORE WATERS. THE DENSE FOG SHOULD
LINGER INTO MID MORNING...AS WINDS BECOME LIGHT. A DENSE FOG
ADVISORY CONTINUES UNTIL 15Z.
AREAS OF FOG WILL LINGER THROUGH THE REST OF TODAY...BEFORE ENDING
FROM NORTH TO SOUTH TUESDAY NIGHT...AS DRIER AIR MOVES INTO THE AREA.
EXPECT ANOTHER DAY OF DIURUNALLY DRIVEN MOIST CONVECTION. WITH THE
WEAK WINDS AND SLOW MOVEMENT...ANY OF THE THUNDERSTORMS COULD
PRODUCE LOCALLY HEAVY RAINFALL. SEVERE HAIL PARAMETERS ARE
LOW...BUT ISOLATED WET MICROBURSTS ARE POSSIBLE.
&&
.MKX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
LM...DENSE FOG ADVISORY UNTIL 1 PM CDT THIS AFTERNOON FOR LMZ643>646.
&&
$$
TODAY/TONIGHT AND AVIATION/MARINE...HENTZ
WEDNESDAY THROUGH MONDAY...DDV
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
1125 PM CDT MON MAY 26 2014
.UPDATE...
ISSUED AT 748 PM CDT MON MAY 26 2014
CONVECTION HAS REMAINED TAME EARLY THIS EVENING ACROSS THE
FORECAST AREA...DUE TO A COMBINATION OF POOR MID LEVEL LAPSE
RATES...SURFACE BASED CAPE MAINLY IN THE RANGE OF 500-1500 J/KG...
AND LACK OF A STRONG DYNAMIC FORCING MECHANISM. IN FACT...
LIGHTNING HAS BEEN ISOLATED AT BEST WITH MUCH OF THE CONVECTION
VERTICALLY IN THE ZONE WARMER THAN -4C. THE ONLY REAL NOTICEABLE
MID-LEVEL DYNAMIC FEATURE IS AN UPPER LOW SITUATED OVER SOUTHWEST
MN...SEEN BOTH IN WATER VAPOR AND RADAR IMAGERY.
MUCH OF THE CONVECTION IS STRONGLY DRIVEN BY INSTABILITY PRODUCED
BY DAYTIME HEATING. THUS...AS RAIN AND OUTFLOW OCCUR...THE STORMS
DISSIPATE. NOW THAT WE ARE HEADING INTO THE NOCTURNAL COOLING
PERIOD AND NO EVIDENCE OF ANY LOW LEVEL MOISTURE TRANSPORT TO HELP
KEEP CONVECTION GOING...ANTICIPATING THE COOLING TEMPERATURES TO
CAUSE THE CONVECTION TO GRADUALLY DISSIPATE. HRRR AS WELL AS THE
26.12Z PARALLEL RUNS OF THE HIRES ARW/NMM ARE IN VERY GOOD
AGREEMENT WITH THIS SCENARIO AS WELL. THEREFORE...HAVE LOWERED
PRECIPITATION CHANCES AFTER MIDNIGHT TO JUST 20. ITS POSSIBLE A
GOOD PORTION OF THE FORECAST AREA ENDS UP DRY BUT HARD TO TELL
WHERE. GIVEN THE LACK OF LIGHTNING EARLY THIS EVENING AND
DIMINISHING INSTABILITY THROUGH THE EVENING...HAVE ALSO REMOVED
THUNDER AFTER MIDNIGHT INTO MID TUESDAY MORNING.
RAISED LOW TEMPERATURES AS WELL A COUPLE DEGREES AS MOIST AIRMASS
COMBINED WITH CLOUDS FROM CONVECTIVE BLOWOFF/SUBTROPICAL MOISTURE
ALOFT HELP TO LIMIT THE TEMPERATURE FALL.
&&
.SHORT TERM...(TONIGHT AND TUESDAY)
ISSUED AT 235 PM CDT MON MAY 26 2014
AFTER A WEEK OF DRY WEATHER...AIRMASS-LIKE SHOWERS AND THUNDERSTORMS
HAVE BEEN FORMING AROUND THE REGION NOW THAT DEEPER MOISTURE AND
SUBTLE LIFT IS IN PLACE. SLIGHTLY HIGHER MIXED LAYER CAPE VALUES
OVER SOUTHERN WISCONSIN GENERATING BULK OF SCATTERED THUNDERSTORM
ACTIVITY AS OF 19Z BUT STILL EXPECTING MORE DEVELOPMENT HEADING INTO
THE EVENING. EVEN WITH MODEST INSTABILITY OUT THERE...WIND SHEAR
NEXT TO NOTHING SO OUTSIDE OF SOME EFFICIENT RAIN PRODUCERS AND
OCCASIONAL LIGHTNING...SEVERE WEATHER THREAT IS LOW.
WITH UPPER LOW STILL PART OF BLOCKED FLOW ACROSS SOUTHERN PLAINS...
STRONGER NORTHERN FLOW OVER RIDGE IS PUSHING A WEAK COLD FRONT
CLOSER TO AREA...STRETCHED ACROSS CENTRAL MINNESOTA THIS AFTERNOON.
THIS FEATURE SHOULD ALSO AID IN ADDITIONAL CONVECTIVE DEVELOPMENT
TONIGHT INTO TUESDAY AS IT SLOWLY SLIDES THROUGH.
CONTINUE TO TRY AND EMPHASIZE HIGHER RAIN THREATS DURING HEATING
PERIODS AND EARLY EVENING...WITH LOWER POPS OVERNIGHT BUT COVERAGE
AREA AND TIMING A BIT DIFFICULT WITH NO DISTINCT FEATURES TO FOCUS
ON. MODEL GUIDANCE CONTINUES TO SUGGEST STORM DEVELOPMENT COULD BE
MORE ACROSS SOUTHERN FORECAST AREA TUESDAY GIVEN FRONT PLACEMENT SO
KEPT LIKELY CHANCES GOING.
.LONG TERM...(TUESDAY NIGHT THROUGH MONDAY)
ISSUED AT 235 PM CDT MON MAY 26 2014
THERE HAS BEEN QUESTIONS ABOUT HOW FAR THIS FRONTAL BOUNDARY WILL
PUSH SOUTH LATER IN THE WEEK FOR DAYS NOW. SIGNAL FOR A DRYING TREND
IS A BIT STRONGER AND FASTER VIA 26.12Z MEDIUM RANGE GUIDANCE. AS
UPPER RIDGE BUILDS IN WEDNESDAY...DRIER NORTHEAST TO EAST LOW LEVEL
FLOW WILL LIKELY PUSH REMNANTS OF FRONT SOUTH SO RAIN CHANCES WILL
ALSO BE LOWERED AND SHIFTED THAT DIRECTION BEFORE GOING ALL DRY FROM
WEDNESDAY NIGHT INTO THE WEEKEND. ABOVE NORMAL TEMPERATURES LIKELY
IN THIS FLOW WITH MAINLY 80S FOR HIGHS.
NEXT WEEK FAIRLY CONSISTENT SIGNAL OF SHORT WAVE ACROSS THE NORTHERN
U.S. DRIVING A STRONGER COLD FRONT TOWARDS THE WESTERN GREAT LAKES.
TOO FAR OUT IN THE FORECAST PROCESS FOR TIMING DETAILS BUT BULK OF
RAIN COULD HOLD OFF TO THE WEST AND NORTHWEST FOR SATURDAY BEFORE
FRONT CRASHES THROUGH SUNDAY WITH MUCH HIGHER STORM THREAT.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT)
ISSUED AT 1125 PM CDT MON MAY 26 2014
ISOLATED-SCATTERED SHOWERS PERSIST NEAR THE TAF SITES...RESULTING
FROM LINGERING INSTABILITY AND AN APPROACHING LOW PRESSURE AREA IN
SOUTHWEST MINNESOTA. HAVE MAINTAINED A VCSH WITH NO VISIBILITY
RESTRICTION UNTIL 09Z IN CASE THESE IMPACT THE SITES. SO FAR THE
SITES HAVE AVOIDED RAINFALL...WHICH IS SIGNIFICANT TO WHETHER OR
NOT BR WILL FORM THIS MORNING. HAVE CONTINUED A VFR BR MENTION...
BUT SHOULD RAIN IMPACT A TAF SITE...VISIBILITIES IN THAT 09-14Z
WINDOW COULD DROP TO MVFR OR EVEN BRIEFLY TOUCH IFR. DAYTIME
HEATING COMBINED WITH THE APPROACHING LOW AS WELL AS A COLD FRONT
DROPPING OUT OF NORTHERN WI SHOULD HELP INITIATE MORE SHOWERS AND
THUNDERSTORMS...ESPECIALLY IN THE AFTERNOON. RIGHT NOW IT APPEARS
THE 20-02Z TIME PERIOD WOULD BE MOST LIKELY FOR THE TAF SITES TO
EXPERIENCE THE THUNDERSTORMS. FURTHER REFINEMENT TO INCLUDE TSRA
AND SUB VFR CEILINGS/VISIBILITIES IS LIKELY IN LATER FORECASTS
WITH A GOOD SIGNAL SOMETIME IN THAT 20-02Z PERIOD FOR STORMS.
SOME SHOWERS COULD LINGER BEYOND 02Z BUT ANTICIPATING THE REST OF
THE EVENING TO SEE VFR CEILINGS AND VISIBILITIES. MAY HAVE TO
WATCH FOR ANOTHER ROUND OF BR AFTER 06Z.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
UPDATE...AJ
SHORT TERM...SHEA
LONG TERM....SHEA
AVIATION...AJ
AREA FORECAST DISCUSSION...UPDATED
NWS CHEYENNE WY
1231 PM MDT TUE MAY 27 2014
.UPDATE...
ISSUED AT 1230 PM MDT TUE MAY 27 2014
ISSUED A QUICK UPDATE TO BUMP POPS DOWN UNTIL 3 PM FOR MOST AREAS
WHERE WE HAD SLIGHT CHANCE OF THUNDERSTORMS IN FORECAST.
CONVECTIVE INITIATION IS LATER GETTING STARTED TODAY WITH WARMER
MIDLEVEL TEMPS. WE ARE STARTING TO SEE SOME CONVECTIVE TOWERS
GOING UP OVER THE NORTHERN LARAMIE RANGE AND OVER THE SNOWY RANGE
AROUND ENCAMPMENT WITH AN ISOLATED SHOWER STARTING AROUND HARRIS
PARK. OTHERWISE...SATELLITE AND RADAR ARE FAIRLY CLEAR MOST ZONES.
WITH HIGH INSOLATION...RELATIVELY LIGHT BOUNDARY LAYER WINDS AND
DRIER AIRMASS WE ARE SEEING TEMPS RISE A LITTLE QUICKER TODAY SO
BUMPED WESTERN NEBRASKA PANHANDLE ZONES UP INTO THE UPPER 80S AND
LOWERED DEWPOINTS A FEW DEGREES IN THE CENTRAL AND EASTERN ZONES.
OTHER PARAMETERS ON TRACK FOR THE REST OF TODAY.
&&
.SHORT TERM...(TODAY THROUGH THURSDAY)
ISSUED AT 345 AM MDT TUE MAY 27 2014
WATER VAPOR SATELLITE AND OBJECTIVE UPPER AIR ANALYSIS SHOW THE
STRONG UPPER LOW TRANSLATING EWD INTO THE SOUTHERN PLAINS STATES
EARLY THIS AM. TRANQUIL WEATHER HAS BEEN THE RULE FOR MUCH OF THE
OVERNIGHT PERIOD AS UPPER-LEVEL RIDGING BUILDS INTO THE CWA IN
RESPONSE TO THE DEPARTING LOW. SAW SOME SCATTERED SHOWERS DEVELOP
AROUND CYS SHORTLY AFTER MIDNIGHT ALONG OUTFLOW ORIGINATING FROM
ACTIVITY OVER HIGHER TERRAIN OUT WEST. JUST A FEW HUNDREDTHS OF AN
INCH REPORTED FROM THAT ACTIVITY BEFORE DISSIPATING. WARMING TREND
CONTINUES TODAY WITH WIDESPREAD H7 TEMPS IN THE TEENS C. POTENTIAL
WILL EXIST FOR AFTN CONVECTION...WITH THE GREATEST COVERAGE OVER
THE MOUNTAINS. LARGE SCALE SUBSIDENCE BENEATH THE RIDGE WILL MOST
LIKELY LIMIT STORM COVERAGE. HOWEVER...THE MODELS SUGGEST NEAR-SFC
UPSLOPE FLOW WILL GRADUALLY DEVELOP AHEAD OF A WEAK SFC LOW MOVING
ACROSS SOUTHWEST WY. RESULTING LLVL CONVERGENCE COULD INITIATE A
FEW TSTMS IN A MODERATELY UNSTABLE AIR MASS CHARACTERIZED BY CAPES
BETWEEN 1000 AND 1500 J/KG AS ADVERTISED BY THE NAM. LIGHT QPF IS
BEING GENERATED BY THE NAM AND ECMWF...AND A FEW CELLS ARE SHOWING
UP ON THE HRRR BY 20Z. ADDED SLIGHT CHANCE POPS OVER THE PLAINS...
MAINLY NORTH AND EAST ALONG THE EDGE OF THE RIDGE WHERE INHIBITION
WILL BE WEAKEST.
WARMEST DAY OF THE PERIOD SHOULD BE WED. 1000-500 HPA THICKNESSES
INCREASE TO AROUND 580 DM AMID EXCELLENT SUBSIDENCE WITH MUCH OF
THE CWA DIRECTLY UNDER THE THERMAL RIDGE AXIS. MAV/MET GUIDANCE
STILL SUGGESTING MID 90S FOR CDR...WHILE THE ECM IS COOLER. GIVEN
THE FAVORABLE PATTERN...CONTINUED TO TREND UPWARDS FOR FCST HIGHS
WITH WIDESPREAD UPPER 80S AND LOW 90S OVER LOWER ELEVATIONS. ANY
CONVECTIVE CHANCES FOR WED SHOULD BE CONFINED TO AREAS WEST OF THE
LARAMIE RANGE...CLOSER TO TO THE MIDLVL SOUTHWESTERLIES. PATTERN
REMAINS INTACT THROUGH THU WITH TSTM CHANCES INCREASING AS THE
RIDGE AXIS SHIFTS EWD AND ALLOWS A MORE MONSOONAL PATTERN TO TAKE
SHAPE OVER THE CWA WITH REMNANT TROPICAL MOISTURE STREAMING NWD
INTO THE CENTRAL ROCKIES FROM HURRICANE AMANDA. AN UNSTABLE AIR
MASS AND IMPROVING VERTICAL SHEAR PROFILES SUGGESTS AN INCREASED
RISK FOR STRONG TO SEVERE STORMS LATE IN THE PERIOD.
.LONG TERM...(FRIDAY THROUGH MONDAY)
ISSUED AT 345 AM MDT TUE MAY 27 2014
UPPER TROUGH DIGGING ONTO THE PACIFIC COAST LATE THIS WEEK WILL PULL
MID AND UPPER LEVEL MOISTURE NORTHWARD FROM REMNANTS OF HURRICANE
AMANDA WHICH IS CURRENTLY SOUTH OF BAJA CALIFORNIA. THIS MOISTURE
COULD FURTHER AGGRAVATE RIVER FLOODING OVER PORTIONS OF SOUTHEAST
WYOMING AS ANY RAINFALL WILL ENHANCE SNOWMELT WHILE ALSO ADDING
MOISTURE TO THE RIVERS. SEE THE HYDROLOGICAL DISCUSSION BELOW FOR
MORE INFORMATION.
CHANCES FOR SHOWERS AND THUNDERSTORMS WILL INCREASE THURSDAY NIGHT
INTO FRIDAY. TIMING OF LEFTOVER AMANDA MOISTURE WILL BE CRITICAL.
SHOULD THE BULK OF THE MOISTURE MOVE THROUGH THURSDAY NIGHT INTO
FRIDAY MORNING...THE CHANCES FOR HIGH RAINFALL RATES AND WIDESPREAD
SHOWERS AND THUNDERSTORMS WILL BE REDUCED. BUT SHOULD MOST OF THE
MOISTURE MOVE INTO THE AREA FRIDAY AFTERNOON/EVENING...THAT WOULD BE
A DIFFERENT STORY. AT THIS TIME THE GFS PUSHES THE BULK OF THE
MOISTURE EAST OF THE MOUNTAINS BY FRIDAY AFTERNOON. WILL KEEP A
CLOSE EYE ON THIS THE NEXT FEW DAYS.
INTO THE WEEKEND AND EARLY NEXT WEEK THE WEATHER PATTERN LOOKS TO
REMAIN ACTIVE WITH AN UPPER TROUGH HANGING OVER THE WESTERN 1/3RD OF
THE CONUS. THIS WILL ALLOW ENERGY TO PERIODICAL MOVE INTO THE
ROCKIES. LIKE USUAL THE DEVIL WILL BE IN THE DETAILS. ECMWF AND GFS
HAVE DIFFERENT IDEAS ON THE LOCATIONS OF A FRONTAL BOUNDARY THIS
WEEKEND. THE GFS MUCH MORE AGGRESSIVE PUSHING THE BOUNDARY
NORTH...MAKING FOR A VERY WARM TO DOWN RIGHT HOT WEEKEND WITH HIGHS
MOSTLY IN THE 80S AND 90S WITH MINIMAL CHANCES FOR THUNDERSTORMS.
THE ECMWF PLACES THE BOUNDARY NEAR THE WYOMING COLORADO BORDER...
WHICH WOULD MEAN COOLER TEMPERATURES BUT ALSO THE POTENTIAL FOR
WIDESPREAD THUNDERSTORM ACTIVITY AND A GREATER THREAT FOR SEVERE
STORMS. REGARDLESS OF WHICH SOLUTION IS CLOSER TO REALITY...THE
BATTLE GROUND BETWEEN COOL AIR TO THE NORTH AND WARM TO THE SOUTH IS
LIKELY TO BE IN PLACE WELL INTO NEXT WEEK.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY MORNING)
ISSUED AT 1047 AM MDT TUE MAY 27 2014
VFR CONDITIONS EXPECTED THROUGH THE NEXT 24 HOURS WITH WESTERLY
DOWNSLOPING WINDS. STILL SOME RESIDUAL MOISTURE THIS AFTERNOON
FOR ISOLATED THUNDERSTORM ACTIVITY OUT IN THE PANHANDLE AND HERE
IN SOUTHEAST WYOMING AT KCYS AND KRWL. ADDED VCTS WORDING INTO
TAFS FOR LATE AFTERNOON/EARLY EVENING TO ACCOUNT FOR THIS
ACTIVITY. CONVECTION TO END SHORTLY AFTER SUNSET.
&&
.FIRE WEATHER...
ISSUED AT 259 AM MDT TUE MAY 27 2014
MINIMAL FIRE WEATHER CONCERNS THROUGH THIS AFTERNOON. AREA FUELS
ARE STILL IN GREEN UP AND SOME LOCATIONS HAVE SEEN SIGNIFICANT
RAINFALL OVER THE WEEKEND. THE WEATHER WILL TREND WARMER AND DRIER
THROUGH THE REMAINDER OF THE WEEK AS A STRONG HIGH PRESSURE RIDGE
BUILDS INTO THE CENTRAL ROCKIES AND HIGH PLAINS. ELEVATED FIRE
WEATHER CONCERNS ON WEDNESDAY AND THURSDAY AFTERNOONS MAINLY FOR
AREAS ALONG AND WEST OF THE LARAMIE RANGE. RH VALUES COULD FALL
BELOW 15 PERCENT ALONG WITH GUSTY SOUTHWEST WINDS BETWEEN 20 AND
25 MPH.
&&
.HYDROLOGY...
ISSUED AT 259 AM MDT TUE MAY 27 2014
EVERYTHING IS STILL ON TRACK FOR AN EXTENDED PERIOD OF VERY WARM
TEMPERATURES ACROSS THE AREA. FREEZING LEVELS BETWEEN 14K AND 15K
FEET WILL RESULT IN SIGNIFICANT MELTING OF MOUNTAIN SNOWPACK OVER
THE SNOWY AND SIERRA MADRE RANGES THIS WEEK. FORECAST POINTS AND
SMALLER CREEKS AND STREAMS THAT HAVE NOT ALREADY RISEN TO FLOOD
STAGE ARE LIKELY TO DO SO OVER THE NEXT FEW DAYS. FLOOD WARNINGS
ARE IN EFFECT FOR THE ENCAMPMENT RIVER AT ENCAMPMENT...THE LITTLE
SNAKE RIVER AT SAVERY...AND THE NORTH PLATTE RIVER AT SINCLAIR AND
SARATOGA. WE WENT AHEAD AND EXTENDED THE CURRENT FLOOD WATCH FOR
ANOTHER 24 HOURS...NOW EXPIRING EARLY WED EVENING AS THE SNOW MELT
WILL CERTAINLY NOT BE STOPPING ANYTIME SOON. WILL BE WATCHING FOR
INCREASING PRECIPITATION CHANCES LATE THIS WEEK INTO THE WEEKEND
AS REMNANT TROPICAL MOISTURE STREAMS NORTHWARD INTO THE AREA. FOR
PUBLIC INFORMATION REGARDING THE DEVELOPING FLOOD THREAT...REFER
TO FFACYS. WARNING INFORMATION IS AVAILABLE UNDER FLWCYS AND
FLSCYS.
&&
.CYS WATCHES/WARNINGS/ADVISORIES...
WY...FLOOD WATCH THROUGH WEDNESDAY AFTERNOON FOR WYZ105-109-110-113-
115.
NE...NONE.
&&
$$
UPDATE...GARMON
SHORT TERM...HAMMER
LONG TERM...SML
AVIATION...CLAYCOMB
FIRE WEATHER...HAMMER
HYDROLOGY...HAMMER
AREA FORECAST DISCUSSION
NWS CHEYENNE WY
1053 AM MDT TUE MAY 27 2014
.SHORT TERM...(TODAY THROUGH THURSDAY)
ISSUED AT 345 AM MDT TUE MAY 27 2014
WATER VAPOR SATELLITE AND OBJECTIVE UPPER AIR ANALYSIS SHOW THE
STRONG UPPER LOW TRANSLATING EWD INTO THE SOUTHERN PLAINS STATES
EARLY THIS AM. TRANQUIL WEATHER HAS BEEN THE RULE FOR MUCH OF THE
OVERNIGHT PERIOD AS UPPER-LEVEL RIDGING BUILDS INTO THE CWA IN
RESPONSE TO THE DEPARTING LOW. SAW SOME SCATTERED SHOWERS DEVELOP
AROUND CYS SHORTLY AFTER MIDNIGHT ALONG OUTFLOW ORIGINATING FROM
ACTIVITY OVER HIGHER TERRAIN OUT WEST. JUST A FEW HUNDREDTHS OF AN
INCH REPORTED FROM THAT ACTIVITY BEFORE DISSIPATING. WARMING TREND
CONTINUES TODAY WITH WIDESPREAD H7 TEMPS IN THE TEENS C. POTENTIAL
WILL EXIST FOR AFTN CONVECTION...WITH THE GREATEST COVERAGE OVER
THE MOUNTAINS. LARGE SCALE SUBSIDENCE BENEATH THE RIDGE WILL MOST
LIKELY LIMIT STORM COVERAGE. HOWEVER...THE MODELS SUGGEST NEAR-SFC
UPSLOPE FLOW WILL GRADUALLY DEVELOP AHEAD OF A WEAK SFC LOW MOVING
ACROSS SOUTHWEST WY. RESULTING LLVL CONVERGENCE COULD INITIATE A
FEW TSTMS IN A MODERATELY UNSTABLE AIR MASS CHARACTERIZED BY CAPES
BETWEEN 1000 AND 1500 J/KG AS ADVERTISED BY THE NAM. LIGHT QPF IS
BEING GENERATED BY THE NAM AND ECMWF...AND A FEW CELLS ARE SHOWING
UP ON THE HRRR BY 20Z. ADDED SLIGHT CHANCE POPS OVER THE PLAINS...
MAINLY NORTH AND EAST ALONG THE EDGE OF THE RIDGE WHERE INHIBITION
WILL BE WEAKEST.
WARMEST DAY OF THE PERIOD SHOULD BE WED. 1000-500 HPA THICKNESSES
INCREASE TO AROUND 580 DM AMID EXCELLENT SUBSIDENCE WITH MUCH OF
THE CWA DIRECTLY UNDER THE THERMAL RIDGE AXIS. MAV/MET GUIDANCE
STILL SUGGESTING MID 90S FOR CDR...WHILE THE ECM IS COOLER. GIVEN
THE FAVORABLE PATTERN...CONTINUED TO TREND UPWARDS FOR FCST HIGHS
WITH WIDESPREAD UPPER 80S AND LOW 90S OVER LOWER ELEVATIONS. ANY
CONVECTIVE CHANCES FOR WED SHOULD BE CONFINED TO AREAS WEST OF THE
LARAMIE RANGE...CLOSER TO TO THE MIDLVL SOUTHWESTERLIES. PATTERN
REMAINS INTACT THROUGH THU WITH TSTM CHANCES INCREASING AS THE
RIDGE AXIS SHIFTS EWD AND ALLOWS A MORE MONSOONAL PATTERN TO TAKE
SHAPE OVER THE CWA WITH REMNANT TROPICAL MOISTURE STREAMING NWD
INTO THE CENTRAL ROCKIES FROM HURRICANE AMANDA. AN UNSTABLE AIR
MASS AND IMPROVING VERTICAL SHEAR PROFILES SUGGESTS AN INCREASED
RISK FOR STRONG TO SEVERE STORMS LATE IN THE PERIOD.
.LONG TERM...(FRIDAY THROUGH MONDAY)
ISSUED AT 345 AM MDT TUE MAY 27 2014
UPPER TROUGH DIGGING ONTO THE PACIFIC COAST LATE THIS WEEK WILL PULL
MID AND UPPER LEVEL MOISTURE NORTHWARD FROM REMNANTS OF HURRICANE
AMANDA WHICH IS CURRENTLY SOUTH OF BAJA CALIFORNIA. THIS MOISTURE
COULD FURTHER AGGRAVATE RIVER FLOODING OVER PORTIONS OF SOUTHEAST
WYOMING AS ANY RAINFALL WILL ENHANCE SNOWMELT WHILE ALSO ADDING
MOISTURE TO THE RIVERS. SEE THE HYDROLOGICAL DISCUSSION BELOW FOR
MORE INFORMATION.
CHANCES FOR SHOWERS AND THUNDERSTORMS WILL INCREASE THURSDAY NIGHT
INTO FRIDAY. TIMING OF LEFTOVER AMANDA MOISTURE WILL BE CRITICAL.
SHOULD THE BULK OF THE MOISTURE MOVE THROUGH THURSDAY NIGHT INTO
FRIDAY MORNING...THE CHANCES FOR HIGH RAINFALL RATES AND WIDESPREAD
SHOWERS AND THUNDERSTORMS WILL BE REDUCED. BUT SHOULD MOST OF THE
MOISTURE MOVE INTO THE AREA FRIDAY AFTERNOON/EVENING...THAT WOULD BE
A DIFFERENT STORY. AT THIS TIME THE GFS PUSHES THE BULK OF THE
MOISTURE EAST OF THE MOUNTAINS BY FRIDAY AFTERNOON. WILL KEEP A
CLOSE EYE ON THIS THE NEXT FEW DAYS.
INTO THE WEEKEND AND EARLY NEXT WEEK THE WEATHER PATTERN LOOKS TO
REMAIN ACTIVE WITH AN UPPER TROUGH HANGING OVER THE WESTERN 1/3RD OF
THE CONUS. THIS WILL ALLOW ENERGY TO PERIODICAL MOVE INTO THE
ROCKIES. LIKE USUAL THE DEVIL WILL BE IN THE DETAILS. ECMWF AND GFS
HAVE DIFFERENT IDEAS ON THE LOCATIONS OF A FRONTAL BOUNDARY THIS
WEEKEND. THE GFS MUCH MORE AGGRESSIVE PUSHING THE BOUNDARY
NORTH...MAKING FOR A VERY WARM TO DOWN RIGHT HOT WEEKEND WITH HIGHS
MOSTLY IN THE 80S AND 90S WITH MINIMAL CHANCES FOR THUNDERSTORMS.
THE ECMWF PLACES THE BOUNDARY NEAR THE WYOMING COLORADO BORDER...
WHICH WOULD MEAN COOLER TEMPERATURES BUT ALSO THE POTENTIAL FOR
WIDESPREAD THUNDERSTORM ACTIVITY AND A GREATER THREAT FOR SEVERE
STORMS. REGARDLESS OF WHICH SOLUTION IS CLOSER TO REALITY...THE
BATTLE GROUND BETWEEN COOL AIR TO THE NORTH AND WARM TO THE SOUTH IS
LIKELY TO BE IN PLACE WELL INTO NEXT WEEK.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY MORNING)
ISSUED AT 1047 AM MDT TUE MAY 27 2014
VFR CONDITIONS EXPECTED THROUGH THE NEXT 24 HOURS WITH WESTERLY
DOWNSLOPING WINDS. STILL SOME RESIDUAL MOISTURE THIS AFTERNOON
FOR ISOLATED THUNDERSTORM ACTIVITY OUT IN THE PANHANDLE AND HERE
IN SOUTHEAST WYOMING AT KCYS AND KRWL. ADDED VCTS WORDING INTO
TAFS FOR LATE AFTERNOON/EARLY EVENING TO ACCOUNT FOR THIS
ACTIVITY. CONVECTION TO END SHORTLY AFTER SUNSET.
&&
.FIRE WEATHER...
ISSUED AT 259 AM MDT TUE MAY 27 2014
MINIMAL FIRE WEATHER CONCERNS THROUGH THIS AFTERNOON. AREA FUELS
ARE STILL IN GREEN UP AND SOME LOCATIONS HAVE SEEN SIGNIFICANT
RAINFALL OVER THE WEEKEND. THE WEATHER WILL TREND WARMER AND DRIER
THROUGH THE REMAINDER OF THE WEEK AS A STRONG HIGH PRESSURE RIDGE
BUILDS INTO THE CENTRAL ROCKIES AND HIGH PLAINS. ELEVATED FIRE
WEATHER CONCERNS ON WEDNESDAY AND THURSDAY AFTERNOONS MAINLY FOR
AREAS ALONG AND WEST OF THE LARAMIE RANGE. RH VALUES COULD FALL
BELOW 15 PERCENT ALONG WITH GUSTY SOUTHWEST WINDS BETWEEN 20 AND
25 MPH.
&&
.HYDROLOGY...
ISSUED AT 259 AM MDT TUE MAY 27 2014
EVERYTHING IS STILL ON TRACK FOR AN EXTENDED PERIOD OF VERY WARM
TEMPERATURES ACROSS THE AREA. FREEZING LEVELS BETWEEN 14K AND 15K
FEET WILL RESULT IN SIGNIFICANT MELTING OF MOUNTAIN SNOWPACK OVER
THE SNOWY AND SIERRA MADRE RANGES THIS WEEK. FORECAST POINTS AND
SMALLER CREEKS AND STREAMS THAT HAVE NOT ALREADY RISEN TO FLOOD
STAGE ARE LIKELY TO DO SO OVER THE NEXT FEW DAYS. FLOOD WARNINGS
ARE IN EFFECT FOR THE ENCAMPMENT RIVER AT ENCAMPMENT...THE LITTLE
SNAKE RIVER AT SAVERY...AND THE NORTH PLATTE RIVER AT SINCLAIR AND
SARATOGA. WE WENT AHEAD AND EXTENDED THE CURRENT FLOOD WATCH FOR
ANOTHER 24 HOURS...NOW EXPIRING EARLY WED EVENING AS THE SNOW MELT
WILL CERTAINLY NOT BE STOPPING ANYTIME SOON. WILL BE WATCHING FOR
INCREASING PRECIPITATION CHANCES LATE THIS WEEK INTO THE WEEKEND
AS REMNANT TROPICAL MOISTURE STREAMS NORTHWARD INTO THE AREA. FOR
PUBLIC INFORMATION REGARDING THE DEVELOPING FLOOD THREAT...REFER
TO FFACYS. WARNING INFORMATION IS AVAILABLE UNDER FLWCYS AND
FLSCYS.
&&
.CYS WATCHES/WARNINGS/ADVISORIES...
WY...FLOOD WATCH THROUGH WEDNESDAY AFTERNOON FOR WYZ105-109-110-113-
115.
NE...NONE.
&&
$$
SHORT TERM...HAMMER
LONG TERM...SML
AVIATION...CLAYCOMB
FIRE WEATHER...HAMMER
AREA FORECAST DISCUSSION
NWS CHEYENNE WY
554 AM MDT TUE MAY 27 2014
.SHORT TERM...(TODAY THROUGH THURSDAY)
ISSUED AT 345 AM MDT TUE MAY 27 2014
WATER VAPOR SATELLITE AND OBJECTIVE UPPER AIR ANALYSIS SHOW THE
STRONG UPPER LOW TRANSLATING EWD INTO THE SOUTHERN PLAINS STATES
EARLY THIS AM. TRANQUIL WEATHER HAS BEEN THE RULE FOR MUCH OF THE
OVERNIGHT PERIOD AS UPPER-LEVEL RIDGING BUILDS INTO THE CWA IN
RESPONSE TO THE DEPARTING LOW. SAW SOME SCATTERED SHOWERS DEVELOP
AROUND CYS SHORTLY AFTER MIDNIGHT ALONG OUTFLOW ORIGINATING FROM
ACTIVITY OVER HIGHER TERRAIN OUT WEST. JUST A FEW HUNDREDTHS OF AN
INCH REPORTED FROM THAT ACTIVITY BEFORE DISSIPATING. WARMING TREND
CONTINUES TODAY WITH WIDESPREAD H7 TEMPS IN THE TEENS C. POTENTIAL
WILL EXIST FOR AFTN CONVECTION...WITH THE GREATEST COVERAGE OVER
THE MOUNTAINS. LARGE SCALE SUBSIDENCE BENEATH THE RIDGE WILL MOST
LIKELY LIMIT STORM COVERAGE. HOWEVER...THE MODELS SUGGEST NEAR-SFC
UPSLOPE FLOW WILL GRADUALLY DEVELOP AHEAD OF A WEAK SFC LOW MOVING
ACROSS SOUTHWEST WY. RESULTING LLVL CONVERGENCE COULD INITIATE A
FEW TSTMS IN A MODERATELY UNSTABLE AIR MASS CHARACTERIZED BY CAPES
BETWEEN 1000 AND 1500 J/KG AS ADVERTISED BY THE NAM. LIGHT QPF IS
BEING GENERATED BY THE NAM AND ECMWF...AND A FEW CELLS ARE SHOWING
UP ON THE HRRR BY 20Z. ADDED SLIGHT CHANCE POPS OVER THE PLAINS...
MAINLY NORTH AND EAST ALONG THE EDGE OF THE RIDGE WHERE INHIBITION
WILL BE WEAKEST.
WARMEST DAY OF THE PERIOD SHOULD BE WED. 1000-500 HPA THICKNESSES
INCREASE TO AROUND 580 DM AMID EXCELLENT SUBSIDENCE WITH MUCH OF
THE CWA DIRECTLY UNDER THE THERMAL RIDGE AXIS. MAV/MET GUIDANCE
STILL SUGGESTING MID 90S FOR CDR...WHILE THE ECM IS COOLER. GIVEN
THE FAVORABLE PATTERN...CONTINUED TO TREND UPWARDS FOR FCST HIGHS
WITH WIDESPREAD UPPER 80S AND LOW 90S OVER LOWER ELEVATIONS. ANY
CONVECTIVE CHANCES FOR WED SHOULD BE CONFINED TO AREAS WEST OF THE
LARAMIE RANGE...CLOSER TO TO THE MIDLVL SOUTHWESTERLIES. PATTERN
REMAINS INTACT THROUGH THU WITH TSTM CHANCES INCREASING AS THE
RIDGE AXIS SHIFTS EWD AND ALLOWS A MORE MONSOONAL PATTERN TO TAKE
SHAPE OVER THE CWA WITH REMNANT TROPICAL MOISTURE STREAMING NWD
INTO THE CENTRAL ROCKIES FROM HURRICANE AMANDA. AN UNSTABLE AIR
MASS AND IMPROVING VERTICAL SHEAR PROFILES SUGGESTS AN INCREASED
RISK FOR STRONG TO SEVERE STORMS LATE IN THE PERIOD.
.LONG TERM...(FRIDAY THROUGH MONDAY)
ISSUED AT 345 AM MDT TUE MAY 27 2014
UPPER TROUGH DIGGING ONTO THE PACIFIC COAST LATE THIS WEEK WILL PULL
MID AND UPPER LEVEL MOISTURE NORTHWARD FROM REMNANTS OF HURRICANE
AMANDA WHICH IS CURRENTLY SOUTH OF BAJA CALIFORNIA. THIS MOISTURE
COULD FURTHER AGGRAVATE RIVER FLOODING OVER PORTIONS OF SOUTHEAST
WYOMING AS ANY RAINFALL WILL ENHANCE SNOWMELT WHILE ALSO ADDING
MOISTURE TO THE RIVERS. SEE THE HYDROLOGICAL DISCUSSION BELOW FOR
MORE INFORMATION.
CHANCES FOR SHOWERS AND THUNDERSTORMS WILL INCREASE THURSDAY NIGHT
INTO FRIDAY. TIMING OF LEFTOVER AMANDA MOISTURE WILL BE CRITICAL.
SHOULD THE BULK OF THE MOISTURE MOVE THROUGH THURSDAY NIGHT INTO
FRIDAY MORNING...THE CHANCES FOR HIGH RAINFALL RATES AND WIDESPREAD
SHOWERS AND THUNDERSTORMS WILL BE REDUCED. BUT SHOULD MOST OF THE
MOISTURE MOVE INTO THE AREA FRIDAY AFTERNOON/EVENING...THAT WOULD BE
A DIFFERENT STORY. AT THIS TIME THE GFS PUSHES THE BULK OF THE
MOISTURE EAST OF THE MOUNTAINS BY FRIDAY AFTERNOON. WILL KEEP A
CLOSE EYE ON THIS THE NEXT FEW DAYS.
INTO THE WEEKEND AND EARLY NEXT WEEK THE WEATHER PATTERN LOOKS TO
REMAIN ACTIVE WITH AN UPPER TROUGH HANGING OVER THE WESTERN 1/3RD OF
THE CONUS. THIS WILL ALLOW ENERGY TO PERIODICAL MOVE INTO THE
ROCKIES. LIKE USUAL THE DEVIL WILL BE IN THE DETAILS. ECMWF AND GFS
HAVE DIFFERENT IDEAS ON THE LOCATIONS OF A FRONTAL BOUNDARY THIS
WEEKEND. THE GFS MUCH MORE AGGRESSIVE PUSHING THE BOUNDARY
NORTH...MAKING FOR A VERY WARM TO DOWN RIGHT HOT WEEKEND WITH HIGHS
MOSTLY IN THE 80S AND 90S WITH MINIMAL CHANCES FOR THUNDERSTORMS.
THE ECMWF PLACES THE BOUNDARY NEAR THE WYOMING COLORADO BORDER...
WHICH WOULD MEAN COOLER TEMPERATURES BUT ALSO THE POTENTIAL FOR
WIDESPREAD THUNDERSTORM ACTIVITY AND A GREATER THREAT FOR SEVERE
STORMS. REGARDLESS OF WHICH SOLUTION IS CLOSER TO REALITY...THE
BATTLE GROUND BETWEEN COOL AIR TO THE NORTH AND WARM TO THE SOUTH IS
LIKELY TO BE IN PLACE WELL INTO NEXT WEEK.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z WEDNESDAY MORNING)
ISSUED AT 550 AM MDT TUE MAY 27 2014
MINIMAL AVIATION CONCERNS TODAY OR TONIGHT. WINDS WILL GENERALLY
BE ON THE LIGHT SIDE AT 5 TO 15 MPH ACROSS THE AREA TODAY. SOME
GUSTS UP TO 30 MPH POSSIBLE WEST OF THE LARAMIE RANGE THIS
AFTERNOON. ISOLATED SHOWERS AND THUNDERSTORMS THIS AFTERNOON.
GUSTY WINDS POSSIBLE NEAR SHOWERS AND THUNDERSTORMS. OUTSIDE
THUNDERSTORM ACTIVITY...VFR THROUGH THE TAF PERIOD.
&&
.FIRE WEATHER...
ISSUED AT 259 AM MDT TUE MAY 27 2014
MINIMAL FIRE WEATHER CONCERNS THROUGH THIS AFTERNOON. AREA FUELS
ARE STILL IN GREEN UP AND SOME LOCATIONS HAVE SEEN SIGNIFICANT
RAINFALL OVER THE WEEKEND. THE WEATHER WILL TREND WARMER AND DRIER
THROUGH THE REMAINDER OF THE WEEK AS A STRONG HIGH PRESSURE RIDGE
BUILDS INTO THE CENTRAL ROCKIES AND HIGH PLAINS. ELEVATED FIRE
WEATHER CONCERNS ON WEDNESDAY AND THURSDAY AFTERNOONS MAINLY FOR
AREAS ALONG AND WEST OF THE LARAMIE RANGE. RH VALUES COULD FALL
BELOW 15 PERCENT ALONG WITH GUSTY SOUTHWEST WINDS BETWEEN 20 AND
25 MPH.
&&
.HYDROLOGY...
ISSUED AT 259 AM MDT TUE MAY 27 2014
EVERYTHING IS STILL ON TRACK FOR AN EXTENDED PERIOD OF VERY WARM
TEMPERATURES ACROSS THE AREA. FREEZING LEVELS BETWEEN 14K AND 15K
FEET WILL RESULT IN SIGNIFICANT MELTING OF MOUNTAIN SNOWPACK OVER
THE SNOWY AND SIERRA MADRE RANGES THIS WEEK. FORECAST POINTS AND
SMALLER CREEKS AND STREAMS THAT HAVE NOT ALREADY RISEN TO FLOOD
STAGE ARE LIKELY TO DO SO OVER THE NEXT FEW DAYS. FLOOD WARNINGS
ARE IN EFFECT FOR THE ENCAMPMENT RIVER AT ENCAMPMENT...THE LITTLE
SNAKE RIVER AT SAVERY...AND THE NORTH PLATTE RIVER AT SINCLAIR AND
SARATOGA. WE WENT AHEAD AND EXTENDED THE CURRENT FLOOD WATCH FOR
ANOTHER 24 HOURS...NOW EXPIRING EARLY WED EVENING AS THE SNOW MELT
WILL CERTAINLY NOT BE STOPPING ANYTIME SOON. WILL BE WATCHING FOR
INCREASING PRECIPITATION CHANCES LATE THIS WEEK INTO THE WEEKEND
AS REMNANT TROPICAL MOISTURE STREAMS NORTHWARD INTO THE AREA. FOR
PUBLIC INFORMATION REGARDING THE DEVELOPING FLOOD THREAT...REFER
TO FFACYS. WARNING INFORMATION IS AVAILABLE UNDER FLWCYS AND
FLSCYS.
&&
.CYS WATCHES/WARNINGS/ADVISORIES...
WY...FLOOD WATCH THROUGH WEDNESDAY AFTERNOON FOR WYZ105-109-110-113-
115.
NE...NONE.
&&
$$
SHORT TERM...HAMMER
LONG TERM...SML
AVIATION...SML
FIRE WEATHER...HAMMER
AREA FORECAST DISCUSSION
NWS CHEYENNE WY
419 AM MDT TUE MAY 27 2014
.SHORT TERM...(TODAY THROUGH THURSDAY)
ISSUED AT 345 AM MDT TUE MAY 27 2014
WATER VAPOR SATELLITE AND OBJECTIVE UPPER AIR ANALYSIS SHOW THE
STRONG UPPER LOW TRANSLATING EWD INTO THE SOUTHERN PLAINS STATES
EARLY THIS AM. TRANQUIL WEATHER HAS BEEN THE RULE FOR MUCH OF THE
OVERNIGHT PERIOD AS UPPER-LEVEL RIDGING BUILDS INTO THE CWA IN
RESPONSE TO THE DEPARTING LOW. SAW SOME SCATTERED SHOWERS DEVELOP
AROUND CYS SHORTLY AFTER MIDNIGHT ALONG OUTFLOW ORIGINATING FROM
ACTIVITY OVER HIGHER TERRAIN OUT WEST. JUST A FEW HUNDREDTHS OF AN
INCH REPORTED FROM THAT ACTIVITY BEFORE DISSIPATING. WARMING TREND
CONTINUES TODAY WITH WIDESPREAD H7 TEMPS IN THE TEENS C. POTENTIAL
WILL EXIST FOR AFTN CONVECTION...WITH THE GREATEST COVERAGE OVER
THE MOUNTAINS. LARGE SCALE SUBSIDENCE BENEATH THE RIDGE WILL MOST
LIKELY LIMIT STORM COVERAGE. HOWEVER...THE MODELS SUGGEST NEAR-SFC
UPSLOPE FLOW WILL GRADUALLY DEVELOP AHEAD OF A WEAK SFC LOW MOVING
ACROSS SOUTHWEST WY. RESULTING LLVL CONVERGENCE COULD INITIATE A
FEW TSTMS IN A MODERATELY UNSTABLE AIR MASS CHARACTERIZED BY CAPES
BETWEEN 1000 AND 1500 J/KG AS ADVERTISED BY THE NAM. LIGHT QPF IS
BEING GENERATED BY THE NAM AND ECMWF...AND A FEW CELLS ARE SHOWING
UP ON THE HRRR BY 20Z. ADDED SLIGHT CHANCE POPS OVER THE PLAINS...
MAINLY NORTH AND EAST ALONG THE EDGE OF THE RIDGE WHERE INHIBITION
WILL BE WEAKEST.
WARMEST DAY OF THE PERIOD SHOULD BE WED. 1000-500 HPA THICKNESSES
INCREASE TO AROUND 580 DM AMID EXCELLENT SUBSIDENCE WITH MUCH OF
THE CWA DIRECTLY UNDER THE THERMAL RIDGE AXIS. MAV/MET GUIDANCE
STILL SUGGESTING MID 90S FOR CDR...WHILE THE ECM IS COOLER. GIVEN
THE FAVORABLE PATTERN...CONTINUED TO TREND UPWARDS FOR FCST HIGHS
WITH WIDESPREAD UPPER 80S AND LOW 90S OVER LOWER ELEVATIONS. ANY
CONVECTIVE CHANCES FOR WED SHOULD BE CONFINED TO AREAS WEST OF THE
LARAMIE RANGE...CLOSER TO TO THE MIDLVL SOUTHWESTERLIES. PATTERN
REMAINS INTACT THROUGH THU WITH TSTM CHANCES INCREASING AS THE
RIDGE AXIS SHIFTS EWD AND ALLOWS A MORE MONSOONAL PATTERN TO TAKE
SHAPE OVER THE CWA WITH REMNANT TROPICAL MOISTURE STREAMING NWD
INTO THE CENTRAL ROCKIES FROM HURRICANE AMANDA. AN UNSTABLE AIR
MASS AND IMPROVING VERTICAL SHEAR PROFILES SUGGESTS AN INCREASED
RISK FOR STRONG TO SEVERE STORMS LATE IN THE PERIOD.
.LONG TERM...(FRIDAY THROUGH MONDAY)
ISSUED AT 345 AM MDT TUE MAY 27 2014
UPPER TROUGH DIGGING ONTO THE PACIFIC COAST LATE THIS WEEK WILL PULL
MID AND UPPER LEVEL MOISTURE NORTHWARD FROM REMNANTS OF HURRICANE
AMANDA WHICH IS CURRENTLY SOUTH OF BAJA CALIFORNIA. THIS MOISTURE
COULD FURTHER AGGRAVATE RIVER FLOODING OVER PORTIONS OF SOUTHEAST
WYOMING AS ANY RAINFALL WILL ENHANCE SNOWMELT WHILE ALSO ADDING
MOISTURE TO THE RIVERS. SEE THE HYDROLOGICAL DISCUSSION BELOW FOR
MORE INFORMATION.
CHANCES FOR SHOWERS AND THUNDERSTORMS WILL INCREASE THURSDAY NIGHT
INTO FRIDAY. TIMING OF LEFTOVER AMANDA MOISTURE WILL BE CRITICAL.
SHOULD THE BULK OF THE MOISTURE MOVE THROUGH THURSDAY NIGHT INTO
FRIDAY MORNING...THE CHANCES FOR HIGH RAINFALL RATES AND WIDESPREAD
SHOWERS AND THUNDERSTORMS WILL BE REDUCED. BUT SHOULD MOST OF THE
MOISTURE MOVE INTO THE AREA FRIDAY AFTERNOON/EVENING...THAT WOULD BE
A DIFFERENT STORY. AT THIS TIME THE GFS PUSHES THE BULK OF THE
MOISTURE EAST OF THE MOUNTAINS BY FRIDAY AFTERNOON. WILL KEEP A
CLOSE EYE ON THIS THE NEXT FEW DAYS.
INTO THE WEEKEND AND EARLY NEXT WEEK THE WEATHER PATTERN LOOKS TO
REMAIN ACTIVE WITH AN UPPER TROUGH HANGING OVER THE WESTERN 1/3RD OF
THE CONUS. THIS WILL ALLOW ENERGY TO PERIODICAL MOVE INTO THE
ROCKIES. LIKE USUAL THE DEVIL WILL BE IN THE DETAILS. ECMWF AND GFS
HAVE DIFFERENT IDEAS ON THE LOCATIONS OF A FRONTAL BOUNDARY THIS
WEEKEND. THE GFS MUCH MORE AGGRESSIVE PUSHING THE BOUNDARY
NORTH...MAKING FOR A VERY WARM TO DOWN RIGHT HOT WEEKEND WITH HIGHS
MOSTLY IN THE 80S AND 90S WITH MINIMAL CHANCES FOR THUNDERSTORMS.
THE ECMWF PLACES THE BOUNDARY NEAR THE WYOMING COLORADO BORDER...
WHICH WOULD MEAN COOLER TEMPERATURES BUT ALSO THE POTENTIAL FOR
WIDESPREAD THUNDERSTORM ACTIVITY AND A GREATER THREAT FOR SEVERE
STORMS. REGARDLESS OF WHICH SOLUTION IS CLOSER TO REALITY...THE
BATTLE GROUND BETWEEN COOL AIR TO THE NORTH AND WARM TO THE SOUTH IS
LIKELY TO BE IN PLACE WELL INTO NEXT WEEK.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT)
ISSUED AT 1141 PM MDT MON MAY 26 2014
A FEW LINGERING SHOWERS NEAR THE LARAMIE RANGE WILL DIE OFF BY
07Z. GUSTS UP TO 30 MPH POSSIBLE NEAR THE DYING SHOWERS. VFR
ACROSS THE AREA TONIGHT AND TOMORROW WITH AN UPPER LEVEL RIDGE
BUILDING INTO THE ROCKY MOUNTAIN REGION. GENERALLY LOOKING AT
LIGHT WINDS ACROSS THE AREA TONIGHT AND TUESDAY. SOME GUSTS TO 30
MPH WEST OF THE LARAMIE RANGE.
&&
.FIRE WEATHER...
ISSUED AT 259 AM MDT TUE MAY 27 2014
MINIMAL FIRE WEATHER CONCERNS THROUGH THIS AFTERNOON. AREA FUELS
ARE STILL IN GREEN UP AND SOME LOCATIONS HAVE SEEN SIGNIFICANT
RAINFALL OVER THE WEEKEND. THE WEATHER WILL TREND WARMER AND DRIER
THROUGH THE REMAINDER OF THE WEEK AS A STRONG HIGH PRESSURE RIDGE
BUILDS INTO THE CENTRAL ROCKIES AND HIGH PLAINS. ELEVATED FIRE
WEATHER CONCERNS ON WEDNESDAY AND THURSDAY AFTERNOONS MAINLY FOR
AREAS ALONG AND WEST OF THE LARAMIE RANGE. RH VALUES COULD FALL
BELOW 15 PERCENT ALONG WITH GUSTY SOUTHWEST WINDS BETWEEN 20 AND
25 MPH.
&&
.HYDROLOGY...
ISSUED AT 259 AM MDT TUE MAY 27 2014
EVERYTHING IS STILL ON TRACK FOR AN EXTENDED PERIOD OF VERY WARM
TEMPERATURES ACROSS THE AREA. FREEZING LEVELS BETWEEN 14K AND 15K
FEET WILL RESULT IN SIGNIFICANT MELTING OF MOUNTAIN SNOWPACK OVER
THE SNOWY AND SIERRA MADRE RANGES THIS WEEK. FORECAST POINTS AND
SMALLER CREEKS AND STREAMS THAT HAVE NOT ALREADY RISEN TO FLOOD
STAGE ARE LIKELY TO DO SO OVER THE NEXT FEW DAYS. FLOOD WARNINGS
ARE IN EFFECT FOR THE ENCAMPMENT RIVER AT ENCAMPMENT...THE LITTLE
SNAKE RIVER AT SAVERY...AND THE NORTH PLATTE RIVER AT SINCLAIR AND
SARATOGA. WE WENT AHEAD AND EXTENDED THE CURRENT FLOOD WATCH FOR
ANOTHER 24 HOURS...NOW EXPIRING EARLY WED EVENING AS THE SNOW MELT
WILL CERTAINLY NOT BE STOPPING ANYTIME SOON. WILL BE WATCHING FOR
INCREASING PRECIPITATION CHANCES LATE THIS WEEK INTO THE WEEKEND
AS REMNANT TROPICAL MOISTURE STREAMS NORTHWARD INTO THE AREA. FOR
PUBLIC INFORMATION REGARDING THE DEVELOPING FLOOD THREAT...REFER
TO FFACYS. WARNING INFORMATION IS AVAILABLE UNDER FLWCYS AND
FLSCYS.
&&
.CYS WATCHES/WARNINGS/ADVISORIES...
WY...FLOOD WATCH THROUGH WEDNESDAY AFTERNOON FOR
WYZ105-109-110-113-115.
NE...NONE.
&&
$$
SHORT TERM...HAMMER
LONG TERM...SML
AVIATION...SML
FIRE WEATHER...HAMMER
HYDROLOGY...HAMMER
AREA FORECAST DISCUSSION
NWS CHEYENNE WY
1151 PM MDT MON MAY 26 2014
.UPDATE...
ISSUED AT 1056 PM MDT MON MAY 26 2014
SCATTERED SHOWERS AND T-STORMS REDEVELOPED THIS EVENING OVER CARBON
COUNTY...AND CONTINUE TO MOVE SOUTHEAST THROUGH ALBANY COUNTY AT
THIS HOUR. THE RAP MODEL SHOWS THIS ACTIVITY WEAKENING
SIGNIFICANTLY BY MIDNIGHT...SO ADDED IN MENTION FOR SCT STORMS IN
THE FORECAST THROUGH THIS TIME. NOT CONFIDENT THIS ACTIVITY WILL
MAKE MUCH OF A SPLASH AS IT MOVES EAST OF THE LARAMIE RANGE SINCE
IT WILL LOSE OROGRAPHIC SUPPORT. OTHERWISE...CONDITIONS WILL
REMAIN FAIRLY CALM ACROSS THE CWA TONIGHT WITH PARTLY CLOUDY SKIES
AND LIGHT WINDS.
&&
.SHORT TERM...(THIS EVENING THROUGH WEDNESDAY NIGHT)
ISSUED AT 320 PM MDT MON MAY 26 2014
IN THE VERY NEAR TERM...MAIN CONCERNS ARE WITH TRAINING
THUNDERSTORMS PRODUCING HEAVY RAINS OVER 2 INCHES FROM CHEYENNE
EAST INTO THE SOUTHERN NEBRASKA PANHANDLE. ENVIRONMENT IN
NORTHWESTERLY MIDLEVEL FLOW PATTERN IS CONDUCIVE FOR STORMS TO
REGENERATE TO THE NORTH FOR THE NEXT FEW HOURS. MODERATELY
UNSTABLE AIRMASS IN PLACE REGION-WIDE (MUCAPES AROUND 1000 J/KG)
WITH MOSTLY ISOLATED STORMS EXPECTED THROUGH SUNSET IN THE
NORTHERN AND WESTERN ZONES. STORMS WILL CONTINUE TO BE A LITTLE
MORE NUMEROUS IN THE REGION OF BEST INSTABILITY (MUCAPES 1200-1500
J/KG) SOUTHEAST OF A LARAMIE...TO SCOTTSBLUFF TO CHADRON LINE. WE
CURRENTLY HAVE FLASH FLOOD WARNINGS ONGOING IN PORTIONS OF KIMBALL
AND CHEYENNE COUNTIES OF NEBRASKA WHERE STORMS CONTINUE TO
BACK BUILD AND TRAIN OVER THE SAME AREAS. EXPECT THE COVERAGE OF
STORMS TO TO START DIMINISHING SHORTLY AFTER SUNSET WITH DECREASED
INSTABILITY. 18Z HRRR SHOWS CONVECTION IN THE SOUTHEASTERN
FORECAST AREA DIMINISHING AFTER 01Z...BUT HANGS ON TO SCATTERED
CONVECTION TO THE NORTHWEST COMING OUT OF THE CASPER AREA. PROBLEM
IS...HRRR HAS BEEN OVER-FORECASTING CONVECTION TO THE NORTHWEST
TODAY SO FOR NOW WILL HAVE SLIGHT POPS IN THE HIGHER TERRAIN OVER
THE NORTHWESTERN ZONES THROUGH MID EVENING.
AS THE UPPER LOW OVER THE TEXAS PANHANDLE THIS EVENING PUSHES
FARTHER TO THE EAST THROUGH TOMORROW...DEEP LAYERED DRYSLOT (AS
NOTED IN WATER VAPOR IMAGERY EXTENDING FROM CALIFORNIA TO UTAH)
WILL SHIFT EAST ACROSS OUR FORECAST AREA TUESDAY THROUGH
WEDNESDAY. THIS WILL RESULT IN SIGNIFICANTLY DIMINISHED POPS
TUESDAY THROUGH WEDNESDAY WITH SMALL POTENTIAL FOR STORMS IN THE
MOUNTAINS. WITH DEEPLY SUBSIDENT AIRMASS IN PLACE TUESDAY THROUGH
WEDNESDAY...WE HAVE GONE A FEW DEGREES ABOVE MODEL GUIDANCE ON
HIGH TEMPERATURES FOR THE MIDWEEK TIMEFRAME WITH LOWER TO MAYBE
EVEN A FEW MID 90S POSSIBLE SOME AREAS IN THE NEBRASKA PANHANDLE
BY WEDNESDAY...WITH MID TO UPPER 80S IN THE LOWER ELEVATIONS IN
SOUTHEAST WYOMING. THIS WILL ACCELERATE THE SNOWMELT PROCESS
ABOVE 9000 FT...AND WILL CAUSE RISES AND AN INCREASED FLOOD THREAT
ON SOME RIVERS IN THE WEST (PLEASE REFER TO THE HYDROLOGIC
DISCUSSION SECTION IN THIS PRODUCT FOR MORE DETAILED INFORMATION).
.LONG TERM...(THURSDAY THROUGH MONDAY)
ISSUED AT 320 PM MDT MON MAY 26 2014
UNSETTLED WEATHER RETURNS IN THE LONG TERM. FORECAST CHALLENGES
DEAL WITH PRECIP COVERAGE.
FOR THURSDAY...UPPER RIDGE BEGINS TO MOVE EAST INTO THE CENTRAL
PLAINS AND A LONG WAVE TROUGH DEVELOPS OVER THE WEST COAST.
SOUTHWESTERLY FLOW BEGINS TO PULL UP SOME SUBTROPICAL MOISTURE
FROM THE DESERT SOUTHWEST. INITIALLY...IT LOOKS LIKE OUR WESTERN
ZONES WILL SEE THE CONVECTION THURSDAY AFTERNOON. ALL THREE MODELS
ARE SHOWING SOME SHOWER ACTIVITY OUT WEST. ECMWF MOST BULLISH ON
QPF WITH THE GFS KEEPING THIS RAINFALL MAINLY OVER WESTERN
COLORADO.
PWATS CONTINUE TO INCREASE INTO FRIDAY AS THE SUBTROPICAL MOISTURE
TAP GETS GOING. ECMWF HAS SHOWERS EXTENDING FROM ARIZONA ALL THE
WAY UP INTO WESTERN SOUTH DAKOTA FRIDAY. GFS PWATS OVER RAWLINS
INCREASES FROM ROUGHLY .45 INCHES TO OVER .60 INCHES BY FRIDAY.
ECMWF SHOWING WIDESPREAD MODERATE PRECIP OVER THE CWFA FRIDAY
NIGHT INTO SATURDAY ACROSS MUCH OF THE AREA.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY EVENING)
ISSUED AT 1141 PM MDT MON MAY 26 2014
A FEW LINGERING SHOWERS NEAR THE LARAMIE RANGE WILL DIE OFF BY
07Z. GUSTS UP TO 30 MPH POSSIBLE NEAR THE DYING SHOWERS. VFR
ACROSS THE AREA TONIGHT AND TOMORROW WITH AN UPPER LEVEL RIDGE
BUILDING INTO THE ROCKY MOUNTAIN REGION. GENERALLY LOOKING AT
LIGHT WINDS ACROSS THE AREA TONIGHT AND TUESDAY. SOME GUSTS TO 30
MPH WEST OF THE LARAMIE RANGE.
&&
.FIRE WEATHER...
ISSUED AT 320 PM MDT MON MAY 26 2014
MINIMAL FIRE WEATHER CONCERNS THROUGH TUESDAY. FUELS CONTINUE
TO BE IN GREEN UP AND SOME AREAS HAVE SEEN SIGNIFICANT RAINFALL
OVER THE PAST FEW DAYS. WARMER AND DRIER CONDITIONS ARE EXPECTED
WEDNESDAY THROUGH LATE THIS WEEK AS HIGH PRESSURE STRENGTHENS OVER
THE CENTRAL PLAINS INCREASING THE SOUTHERLY WINDS OVER WYOMING
AND NEBRASKA. NEAR-CRITICAL CONDITIONS ARE POSSIBLE MID TO LATE
WEEK AS AFTERNOON HUMIDITY VALUES FALL BELOW 15 PERCENT WITH
GUSTY WINDS EXPECTED OVER THE HIGHER ELEVATIONS. CHANCES OF
SHOWERS AND THUNDERSTORMS WILL INCREASE FRIDAY INTO SATURDAY.
&&
.CYS WATCHES/WARNINGS/ADVISORIES...
WY...FLOOD WATCH THROUGH TUESDAY AFTERNOON FOR WYZ105-109-110-113-115.
NE...NONE.
&&
$$
UPDATE...RJM
SHORT TERM...GARMON
LONG TERM...CLAYCOMB
AVIATION...SML
FIRE WEATHER...GARMON
AREA FORECAST DISCUSSION
NWS CHEYENNE WY
1056 PM MDT MON MAY 26 2014
.UPDATE...
ISSUED AT 1056 PM MDT MON MAY 26 2014
SCATTERED SHOWERS AND T-STORMS REDEVELOPED THIS EVENING OVER CARBON
COUNTY...AND CONTINUE TO MOVE SOUTHEAST THROUGH ALBANY COUNTY AT
THIS HOUR. THE RAP MODEL SHOWS THIS ACTIVITY WEAKENING
SIGNIFICANTLY BY MIDNIGHT...SO ADDED IN MENTION FOR SCT STORMS IN
THE FORECAST THROUGH THIS TIME. NOT CONFIDENT THIS ACTIVITY WILL
MAKE MUCH OF A SPLASH AS IT MOVES EAST OF THE LARAMIE RANGE SINCE
IT WILL LOSE OROGRAPHIC SUPPORT. OTHERWISE...CONDITIONS WILL
REMAIN FAIRLY CALM ACROSS THE CWA TONIGHT WITH PARTLY CLOUDY SKIES
AND LIGHT WINDS.
&&
.SHORT TERM...(THIS EVENING THROUGH WEDNESDAY NIGHT)
ISSUED AT 320 PM MDT MON MAY 26 2014
IN THE VERY NEAR TERM...MAIN CONCERNS ARE WITH TRAINING
THUNDERSTORMS PRODUCING HEAVY RAINS OVER 2 INCHES FROM CHEYENNE
EAST INTO THE SOUTHERN NEBRASKA PANHANDLE. ENVIRONMENT IN
NORTHWESTERLY MIDLEVEL FLOW PATTERN IS CONDUCIVE FOR STORMS TO
REGENERATE TO THE NORTH FOR THE NEXT FEW HOURS. MODERATELY
UNSTABLE AIRMASS IN PLACE REGION-WIDE (MUCAPES AROUND 1000 J/KG)
WITH MOSTLY ISOLATED STORMS EXPECTED THROUGH SUNSET IN THE
NORTHERN AND WESTERN ZONES. STORMS WILL CONTINUE TO BE A LITTLE
MORE NUMEROUS IN THE REGION OF BEST INSTABILITY (MUCAPES 1200-1500
J/KG) SOUTHEAST OF A LARAMIE...TO SCOTTSBLUFF TO CHADRON LINE. WE
CURRENTLY HAVE FLASH FLOOD WARNINGS ONGOING IN PORTIONS OF KIMBALL
AND CHEYENNE COUNTIES OF NEBRASKA WHERE STORMS CONTINUE TO
BACK BUILD AND TRAIN OVER THE SAME AREAS. EXPECT THE COVERAGE OF
STORMS TO TO START DIMINISHING SHORTLY AFTER SUNSET WITH DECREASED
INSTABILITY. 18Z HRRR SHOWS CONVECTION IN THE SOUTHEASTERN
FORECAST AREA DIMINISHING AFTER 01Z...BUT HANGS ON TO SCATTERED
CONVECTION TO THE NORTHWEST COMING OUT OF THE CASPER AREA. PROBLEM
IS...HRRR HAS BEEN OVER-FORECASTING CONVECTION TO THE NORTHWEST
TODAY SO FOR NOW WILL HAVE SLIGHT POPS IN THE HIGHER TERRAIN OVER
THE NORTHWESTERN ZONES THROUGH MID EVENING.
AS THE UPPER LOW OVER THE TEXAS PANHANDLE THIS EVENING PUSHES
FARTHER TO THE EAST THROUGH TOMORROW...DEEP LAYERED DRYSLOT (AS
NOTED IN WATER VAPOR IMAGERY EXTENDING FROM CALIFORNIA TO UTAH)
WILL SHIFT EAST ACROSS OUR FORECAST AREA TUESDAY THROUGH
WEDNESDAY. THIS WILL RESULT IN SIGNIFICANTLY DIMINISHED POPS
TUESDAY THROUGH WEDNESDAY WITH SMALL POTENTIAL FOR STORMS IN THE
MOUNTAINS. WITH DEEPLY SUBSIDENT AIRMASS IN PLACE TUESDAY THROUGH
WEDNESDAY...WE HAVE GONE A FEW DEGREES ABOVE MODEL GUIDANCE ON
HIGH TEMPERATURES FOR THE MIDWEEK TIMEFRAME WITH LOWER TO MAYBE
EVEN A FEW MID 90S POSSIBLE SOME AREAS IN THE NEBRASKA PANHANDLE
BY WEDNESDAY...WITH MID TO UPPER 80S IN THE LOWER ELEVATIONS IN
SOUTHEAST WYOMING. THIS WILL ACCELERATE THE SNOWMELT PROCESS
ABOVE 9000 FT...AND WILL CAUSE RISES AND AN INCREASED FLOOD THREAT
ON SOME RIVERS IN THE WEST (PLEASE REFER TO THE HYDROLOGIC
DISCUSSION SECTION IN THIS PRODUCT FOR MORE DETAILED INFORMATION).
.LONG TERM...(THURSDAY THROUGH MONDAY)
ISSUED AT 320 PM MDT MON MAY 26 2014
UNSETTLED WEATHER RETURNS IN THE LONG TERM. FORECAST CHALLENGES
DEAL WITH PRECIP COVERAGE.
FOR THURSDAY...UPPER RIDGE BEGINS TO MOVE EAST INTO THE CENTRAL
PLAINS AND A LONG WAVE TROUGH DEVELOPS OVER THE WEST COAST.
SOUTHWESTERLY FLOW BEGINS TO PULL UP SOME SUBTROPICAL MOISTURE
FROM THE DESERT SOUTHWEST. INITIALLY...IT LOOKS LIKE OUR WESTERN
ZONES WILL SEE THE CONVECTION THURSDAY AFTERNOON. ALL THREE MODELS
ARE SHOWING SOME SHOWER ACTIVITY OUT WEST. ECMWF MOST BULLISH ON
QPF WITH THE GFS KEEPING THIS RAINFALL MAINLY OVER WESTERN
COLORADO.
PWATS CONTINUE TO INCREASE INTO FRIDAY AS THE SUBTROPICAL MOISTURE
TAP GETS GOING. ECMWF HAS SHOWERS EXTENDING FROM ARIZONA ALL THE
WAY UP INTO WESTERN SOUTH DAKOTA FRIDAY. GFS PWATS OVER RAWLINS
INCREASES FROM ROUGHLY .45 INCHES TO OVER .60 INCHES BY FRIDAY.
ECMWF SHOWING WIDESPREAD MODERATE PRECIP OVER THE CWFA FRIDAY
NIGHT INTO SATURDAY ACROSS MUCH OF THE AREA.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY EVENING)
ISSUED AT 1056 PM MDT MON MAY 26 2014
AN AREA OF SHOWERS AND TSTORMS WILL MOVE OVER THE LARAMIE RANGE
THROUGH 07Z...AND SHOULD DISSIPATE AS IT VENTURES FURTHER EAST
ACROSS THE PLAINS. OTHERWISE...VFR CONDITIONS WILL PREVAIL
THROUGH THE PERIOD WITH GENERALLY LIGHT WINDS EXPECTED. THERE IS
ANOTHER CHANCE FOR ISOLATED T-STORMS LATE TUESDAY AFTERNOON FOR
AREAS ALONG AND WEST OF THE LARAMIE RANGE...WITH A FEW STORMS
DEVELOPING AND MOVING ACROSS THE EASTERN PLAINS AS WELL IN THE
EVENING. GUSTY SOUTHWEST WINDS UP TO 25 KTS ARE LIKELY AT KRWL
AFTER 17Z.
&&
.FIRE WEATHER...
ISSUED AT 320 PM MDT MON MAY 26 2014
MINIMAL FIRE WEATHER CONCERNS THROUGH TUESDAY. FUELS CONTINUE
TO BE IN GREEN UP AND SOME AREAS HAVE SEEN SIGNIFICANT RAINFALL
OVER THE PAST FEW DAYS. WARMER AND DRIER CONDITIONS ARE EXPECTED
WEDNESDAY THROUGH LATE THIS WEEK AS HIGH PRESSURE STRENGTHENS OVER
THE CENTRAL PLAINS INCREASING THE SOUTHERLY WINDS OVER WYOMING
AND NEBRASKA. NEAR-CRITICAL CONDITIONS ARE POSSIBLE MID TO LATE
WEEK AS AFTERNOON HUMIDITY VALUES FALL BELOW 15 PERCENT WITH
GUSTY WINDS EXPECTED OVER THE HIGHER ELEVATIONS. CHANCES OF
SHOWERS AND THUNDERSTORMS WILL INCREASE FRIDAY INTO SATURDAY.
&&
.CYS WATCHES/WARNINGS/ADVISORIES...
WY...FLOOD WATCH THROUGH TUESDAY AFTERNOON FOR WYZ105-109-110-113-115.
NE...NONE.
&&
$$
UPDATE...RJM
SHORT TERM...GARMON
LONG TERM...CLAYCOMB
AVIATION...RJM
FIRE WEATHER...GARMON
HYDROLOGY...CLAYCOMB
AREA FORECAST DISCUSSION
NWS PUEBLO CO
1109 PM MDT WED MAY 28 2014
.SHORT TERM...(THIS EVENING THROUGH THURSDAY)
ISSUED AT 325 PM MDT WED MAY 28 2014
CURRENTLY...
SHOWERS NOTED MAINLY OVER THE HIGHER TRRN...ESPECIALLY ACROSS THE SW
MTNS AND WETS AND S SANGRES. FLOW ALOFT IS WEAK SO SHOWERS MOVING
VERY SLOWLY. OTHERWISE IT WAS QUITE WARM WITH TEMPS IN THE 80S TO 90
ACROSS THE PLAINS...70 TO L80S VALLEYS...AND 50S AND 60S MTNS.
REST OF TODAY AND TONITE...
MAIN CHANGE I MADE TO THE FCST WAS TO INCLUDE SOME LOW END POPS TO N
EL PASO COUNTY AND TO THE SAN LUIS VALLEY FOR THE REST OF THIS
AFTERNOON AND EARLY EVENING. HRRR INDICATING A FEW SHOWERS WILL MOVE
OUT A LITTLE FARTHER ONTO THE PLAINS.
DISTURBANCE OFFSHORE OF S CALIF COAST IS BRINGING IN SOME HIGHER
LEVEL MOISTURE TO THE SW...AND THESE CLOUDS SHOULD MOVE OVER THE
REGION STARTING LATER THIS EVENING.
TOMORROW(THURSDAY)...
SHOULD SEE AN UPTICK IN HIGH CLOUDS AND SHOWERS OVER THE REGION
TOMORROW...WITH A BETTER CHANCE OF SHOWERS MOVING A BIT FARTHER ONTO
THE PLAINS AS FLOW ALOFT SHIFTS TO MORE SW ALOFT...ESPECIALLY OVER
THE WESTERN SECTIONS OF THE PLAINS. FAR EASTERN PLAINS SHOULD REMAIN
DRY THROUGH LATE TOMORROW AFTERNOON. MAX TEMPS TOMORROW SHOULD BE
ABOUT SIMILAR TO TODAYS HIGHS. /HODANISH
.LONG TERM...(THURSDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 325 PM MDT WED MAY 28 2014
PRIMARY METEOROLOGICAL ISSUES DURING THE LONGER TERM APPEAR TO BE
TEMPERATURES AND POPS...WITH ATTENDANT HEAVY RAIN/SEVERE THREAT
AT TIMES DURING PERIODS OF DEEPER ATMOSPHERIC MOISTURE
INTRUSIONS.
INITIALLY...RECENT LONGER TERM COMPUTER SIMULATIONS AND FORECAST
MODEL SOUNDINGS SUGGEST THAT A SOMEWHAT ACTIVE METEOROLOGICAL
PATTERN SHOULD BE NOTED AT TIMES OVER THE FORECAST DISTRICT FROM
THURSDAY EVENING INTO SATURDAY AS UPPER ENERGY ROTATING AROUND
UPPER LOW OVER THE PACIFIC NORTHWEST/INTER-MOUNTAIN REGION
INTERACTS WITH ADEQUATE ATMOSPHERIC MOISTURE VALUES. WFO PUEBLO
WILL NEED TO MONITOR FOR STRONG STORMS AND LOCALLY HEAVY
RAIN(ESPECIALLY OVER/NEAR AREA BURN SCARS) DURING THIS
TIME-FRAME.
SATURDAY NIGHT INTO SUNDAY APPEARS TO BE A TRANSITION DAY TO
DRIER CONDITIONS AS UPPER DISTURBANCE MOVING INTO/ACROSS MONTANA
ALLOWS A DRIER AIRMASS TO DEVELOP OVER THE MAJORITY OF THE CWFA.
FORECAST DISTRICT SHOULD CONTINUE TO NOTICE BASICALLY DRY
CONDITIONS INTO TUESDAY AS TRANSITORY UPPER ZONAL TO UPPER
RIDGING PATTERN IMPACTS THE FORECAST DISTRICT.
A RETURN TO A MORE UNSETTLED METEOROLOGICAL REGIME SHOULD THEN
DEVELOP FROM LATER TUESDAY INTO AT LEAST NEXT WEDNESDAY AS DEEPER
ATMOSPHERIC MOISTURE...NORTHERLY SURGE OVER EASTERN SECTIONS AND
UPPER DISTURBANCES IMPACT SOUTHERN COLORADO.
LATEST COMPUTER SIMULATIONS SUGGEST THAT THE SEVERE WEATHER
THREAT MAY BE INCREASING BY NEXT WEDNESDAY(ESPECIALLY EASTERN
SECTIONS) AS MEAN LAYER SHEAR...ATMOSPHERIC MOISTURE AND
INSTABILITIES ALL BECOME MORE FAVORABLE.
FINALLY...ABOVE CLIMATOLOGICAL LATE MAY/EARLY JUNE TEMPERATURES
ARE ANTICIPATED DURING THE LONGER TERM WITH THE WEEKEND EXPECTED
TO EXPERIENCE THE WARMEST CONDITIONS...WHILE BY MID-WEEK NEXT
WEEK TEMPERATURES DROP TO NEAR SEASONAL AVERAGES.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z THURSDAY NIGHT)
ISSUED AT 1106 PM MDT WED MAY 28 2014
VFR CONDITIONS AT ALL THREE TERMINALS THROUGH THURSDAY LATE
MORNING TO EARLY AFTERNOON. WINDS WILL GENERALLY BE SOUTHERLY
UNDER 15 KTS AT ALL THREE TERMINALS. THE LATEST MODELS DEVELOP
SHOWER AND THUNDERSTORM ACTIVITY OVER THE MOUNTAINS BY EARLY
AFTERNOON AND MOVE IT INTO THE SAN LUIS VALLEY AND PALMER DIVIDE
REGIONS THROUGH THE AFTERNOON AND EVENING...IMPACTING KALS AND
KCOS. MOZLEY
&&
.PUB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AVIATION...MOZLEY
AREA FORECAST DISCUSSION
NWS PEACHTREE CITY GA
128 AM EDT THU MAY 29 2014
.UPDATE...
/ISSUED AT 729 PM EDT WED MAY 28 2014/
OUTFLOW DRIVEN CONVECTION WILL CONTINUE ACROSS MUCH OF THE CWFA
FOR THE NEXT FEW HOURS. HAVE UPDATED THE POPS ACCORDING TO THE
LATEST RADAR TRENDS. ALSO...THE HRRR DOES KEEP SOME ISOLATED
ACTIVITY IN AFTER 06Z...SO HAVE DONE THE SAME.
&&
.PREV DISCUSSION... /ISSUED 341 PM EDT WED MAY 28 2014/
SHORT TERM /TONIGHT THROUGH THURSDAY NIGHT/...
NO SIGNIFICANT CHANGES TO THE GENERAL TRENDS THROUGH THE SHORT TERM
FORECAST PERIOD. STRANDED UPPER LOW OVER THE LOWER MISSISSIPPI
VALLEY GETS NO KICKER TO MOVE AS MEDIUM RANGE MODELS SHOW IT DOES
NOT CONNECT WITH THE EAST COAST UPPER TROUGH BEFORE THE BUILDING
UPPER RIDGE ISOLATES IT ONCE AGAIN. ISOLATED TO SCATTERED DIURNAL
CONVECTION PATTERN WILL CONTINUE THROUGH THURSDAY NIGHT. INDICATIONS
ARE THAT MID-LEVEL LAPSE RATES SLOWLY DECREASE THROUGH THE PERIOD SO
CHANCES FOR STRONG TO SEVERE THUNDERSTORMS...ALTHOUGH NOT ZERO...
REMAIN SMALL AND SHOULD ACTUALLY DIMINISH SOME AGAIN THURSDAY.
OVERNIGHT LOWS ARE EXPECTED TO REMAIN MILD AND NEAR SEASONAL NORMALS
WITH AFTERNOON HIGHS AT OR SLIGHTLY ABOVE AVERAGE.
20
LONG TERM /FRIDAY THROUGH WEDNESDAY/...
LONG TERM FORECAST STILL LOOKS VERY SIMILAR WITH PULSE
THUNDERSTORM CONVECTION EACH DAY THROUGH SATURDAY BUT LOSING SOME
INSTABILITY FOR SUNDAY INTO MONDAY AS A WEDGE HELPS TO STABILIZE
THE AREA. CURRENT LONG TERM FORECAST IS ON TRACK SO VERY LITTLE IN
TERMS OF CHANGES. THE PREVIOUS DISCUSSION FOLLOWS.
11
/ISSUED AT 358 AM EDT WED MAY 28 2014/
MODELS ARE IN GOOD CONSENSUS THROUGH MUCH OF THE LONG TERM. WEAK
UPPER LOW WITH A BROAD AND DEEP MOISTURE FIELD LINGERS ACROSS THE
SOUTHEAST CONUS INTO THE WEEKEND ALLOWING FOR DECENT CHANCE POPS FOR
SHOWERS AND THUNDERSTORMS IN THE AFTERNOON AND EVENING PERIODS THEN
SOME CONTINUED WEAKER ACTIVITY POSSIBLE OVERNIGHT. LITTLE TO NO
SHEAR WITH MODERATE INSTABILITY WILL KEEP CONVECTIVE MODE OF THE
PULSE VARIETY WITH EVOLUTION LARGELY OUTFLOW DRIVEN OR RIDING ALONG
WAVES OF GULF MOISTURE FROM THE SOUTHWEST. SOME STRONG AND FEW
SEVERE STORMS STILL LOOK LIKE A GOOD BET AS HAS BEEN THE RECENT
TREND.
UPPER RIDGING BEGINS TO TAKE OVER SATURDAY INTO SUNDAY AND A SFC
HIGH SLIDING SOUTH ALONG THE EAST COAST LOOKS TO RESULT IN HYBRID
CAD. THE WEDGE FRONT LATER SATURDAY MAY PROVIDE SOME ENHANCED
FORCING AND FOCUS FOR CONVECTION. WHILE THE CAD LOOKS TO BE
SHORT-LIVED AS THE PARENT HIGH SLIDES EVENT FARTHER SOUTH...THE
RIDGING SHOULD STILL SERVE TO STABILIZE MUCH OF THE AREA FROM THE
EAST AND LESSEN SHOWER/STORM POTENTIAL SUNDAY THROUGH MONDAY. BETTER
STORM CHANCE STARTS TO RETURN TO THE AREA BY TUESDAY AS THE RIDGE
BREAKS DOWN.
FOR TEMPS...MADE SLIGHT ADJUSTMENTS FROM A GENERAL BLEND OF GUIDANCE
AND VALUES GENERALLY 5 DEGREES ABOVE NORMAL LOOK REASONABLE.
SLIGHTLY COOLER TEMPS ON TAP SUNDAY AND MONDAY FROM BRIEF WEDGE.
BAKER
&&
.AVIATION...
06Z UPDATE...
ISOLATED CONVECTION CONTINUES OVER NORTH GA BUT THIS SHOULD
DISSIPATE BY 09Z AND SHOULD NOT MOVE OVER ANY OF THE TAF SITES.
AREAS OF FOG WILL DEVELOP IN AHN/MCN/PDK/FTY WHERE RAIN FELL OVER OR
IN THE VICINITY OF THE AIRPORT DURING YESTERDAY EVENING. MUCH OF THE
SAME FOR LATER TODAY WITH CU FIELD FORMING AND SCATTERED CONVECTION
DEVELOPING DURING THE LATE MORNING AND AFTERNOON...DIMINISHING
DURING THE EVENING. WILL MAINTAIN A PROB30 TSRA FOR THE AFTERNOON
ALL LOCATIONS. WINDS WILL REMAIN CALM/NEAR CALM EARLY THIS
MORNING...THEN SOUTHWEST LESS THAN 10 KTS THROUGH THE REST OF TODAY.
//ATL CONFIDENCE...06Z UPDATE...
HIGH CONFIDENCE ON ALL ELEMENTS.
&&
.PRELIMINARY POINT TEMPS/POPS...
ATHENS 65 88 64 88 / 40 40 40 40
ATLANTA 67 85 67 86 / 50 40 30 40
BLAIRSVILLE 59 83 61 82 / 40 40 40 40
CARTERSVILLE 63 86 63 87 / 50 40 30 40
COLUMBUS 68 88 67 88 / 40 40 30 40
GAINESVILLE 66 86 66 86 / 40 40 40 40
MACON 65 88 65 88 / 70 40 30 40
ROME 64 86 63 87 / 50 40 30 40
PEACHTREE CITY 64 86 63 87 / 50 40 30 40
VIDALIA 69 90 69 90 / 70 40 30 40
&&
.FFC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
347 AM CDT THU MAY 29 2014
.DISCUSSION...
346 AM CDT
FORECAST CONCERNS THIS MORNING FOCUS ON DRIER NORTHEAST LOW LEVEL
WINDS TODAY...WITH DECREASING CLOUDINESS AND THREAT OF AFTERNOON
THUNDERSTORMS SHIFTING DOWNSTATE ALONG/SOUTH OF WFO LOT/ILX BORDER.
DRY AND MILD CONDITIONS ANTICIPATED OVER THE NEXT FEW DAYS WITH A
WARMING TREND INTO THE WEEKEND...AND A GRADUAL DECREASE IN LAKE
COOLING. A PERIOD OF ACTIVE WEATHER WITH HEAVY RAINFALL AND
INCREASING SEVERE THUNDERSTORM POTENTIAL APPEARS TO BE SHAPING UP
FOR DAYS 4-7 (SUNDAY-NEXT WEDNESDAY)...AS A COLD FRONT SAGS INTO
WARM/HUMID AIR MASS WHICH TAKES UP RESIDENCE ACROSS THE AREA.
WEAK SURFACE LOW PRESSURE CONTINUES TO SETTLE SOUTHWARD ACROSS
EASTERN MISSOURI THIS MORNING...WITH A NEARLY STATIONARY COLD FRONT
STRETCHING WEST-EAST ACROSS SOUTH CENTRAL IL/IN. THIS BOUNDARY WILL
CONTINUE TO BE THE FOCUS FOR DIURNAL SHOWER/THUNDERSTORM DEVELOPMENT
THIS AFTERNOON...AS WEAKENING SHEARED MID-LEVEL VORT MAXIMA
CONTINUES TO DRIFT SOUTH WHILE GETTING PULLED INTO CIRCULATION
AROUND CLOSED UPPER LOW OVER THE LOWER MISSISSIPPI VALLEY. VARIOUS
HIGH-RES CONVECTIVE-ALLOWING GUIDANCE DEPICTS AFTERNOON CONVECTION
DEVELOPING GENERALLY ALONG/SOUTH OF OUR SOUTHERN CWA BORDER...THUS
HAVE MAINTAINED SOME SLIGHT CHANCE POPS SOUTH OF ABOUT A FAIRBURY TO
WATSEKA TO FOWLER LINE. FARTHER NORTH...NORTHEAST LOW LEVEL WINDS
CONTINUE TO BRING DRIER AND MORE STABLE AIR INTO THE AREA FROM
ACROSS THE LAKES. PATCHY LOW CLOUD COVER OVER PARTS OF THE AREA
SHOULD CLEAR OUT LATER THIS MORNING...WITH MODEL FORECAST SOUNDINGS
INDICATING WARMING AND DRYING FROM ABOVE AS SUBSIDENCE DEVELOPS WITH
UPPER RIDGE BUILDING INTO THE UPPER MIDWEST. THIS UPPER RIDGE
CONTINUES TO BUILD AND SLOWLY DRIFT SOUTHEAST ACROSS THE REGION INTO
SATURDAY...PRODUCING DRY CONDITIONS WITH A STEADY MODERATION IN
TEMPERATURES. SURFACE HIGH PRESSURE WILL REMAIN TO OUR NORTHEAST AND
EAST DURING THE PERIOD...GRADUALLY WEAKENING AND PULLING OFF TO THE
EAST AND ALLOWING NORTHEAST SURFACE WINDS TO GRADUALLY VEER
SOUTHEAST AND DECREASING THE AMOUNT OF LAKE COOLING. WITH A GOOD
AMOUNT OF SUNSHINE EXPECTED TODAY...FRIDAY AND SATURDAY...HAVE
GENERALLY UTILIZED WARMER GUIDANCE FOR HIGH TEMPS...WITH UPPER 70S
AND LOWER 80S EXPECTED TODAY WELL AWAY FROM THE LAKE WARMING TO THE
LOW-MID 80S BY SATURDAY. AS FETCH ACROSS THE LAKE DECREASES WITH
VEERING LOW LEVEL WINDS...SHORE AREAS SHOULD ALSO MODERATE FROM THE
LOW-MID 60S TODAY TO THE LOW-MID 70S BY SATURDAY. DRY AIR WILL
SUPPORT COOL OVERNIGHT TEMPS PARTICULARLY ACROSS NORTHEAST IL...WITH
A FEW UPPER 40S POSSIBLE TONIGHT NEAR THE LAKE.
ON SATURDAY...THE UPPER RIDGE AXIS WILL SHIFT SOUTHEAST OF THE AREA
AS A STRONG UPPER JET MAX SPREADS ACROSS ONTARIO AND THE FAR UPPER
MIDWEST. MEDIUM RANGE MODEL SOLUTIONS ARE IN GOOD AGREEMENT IN
DEPICTING A SHORT WAVE LIFTING FROM THE PLAINS TOWARD THE UPPER
MISSISSIPPI VALLEY SATURDAY AFTERNOON/NIGHT...HELPING INDUCE SURFACE
PRESSURE FALLS ACROSS THE UPPER MISSISSIPPI VALLEY AND VEERING LOW
LEVEL WINDS MORE SOUTHERLY. WARM/MOIST ADVECTION IN RETURN FLOW WILL
BRING WARM AND HUMID CONDITIONS BACK TO THE FORECAST AREA BY
SUNDAY...WITH THE POTENTIAL FOR A FEW ELEVATED THUNDERSTORMS ACROSS
NORTHWEST IL TOWARD SUNDAY MORNING ALONG EASTERN PERIPHERY OF BROAD
SOUTHWESTERLY LOW LEVEL JET AND THE SUBTLE WARM FRONT. POTENTIAL FOR
THUNDERSTORMS INCREASES AS AREA BECOMES FIRMLY ENTRENCHED IN THE
WARM SECTOR SUNDAY AND SUNDAY NIGHT...WITH TEMPS MID-UPPER 80S AND
DEW POINT TEMPS 65-70 PROGGED.
GUIDANCE DIFFERS WITH DETAILS OF SHORT WAVES MOVING THROUGH
SOUTHWEST FLOW ALOFT INTO EARLY NEXT WEEK...THOUGH THE POTENTIAL
EXISTS FOR SEVERAL ROUNDS OF THUNDERSTORMS TO AFFECT THE REGION INTO
AT LEAST TUESDAY AS COLD FRONT SLOWLY MOVES SOUTH INTO A VERY WARM
AND MOIST AIR MASS. WEST-SOUTHWEST TO EAST-NORTHEAST ORIENTATION OF
BOUNDARY COMBINED WITH HIGH PRECIPITABLE WATER VALUES (1.5-2.0
INCHES PER GFS SOUNDINGS) WILL LIKELY SUPPORT A HEAVY RAINFALL
THREAT...AND INCREASING DEEP LAYER BULK SHEAR ESPECIALLY MON-WED
ALSO SUGGESTS SEVERE MCS POTENTIAL. FOR NOW HAVE MAINTAINED RATHER
BROAD-BRUSHED CHANCE POPS FROM SUNDAY ONWARD...THOUGH DETAILS SUCH
AS THE LOCATION OF THE FRONTAL BOUNDARY (LIKELY MODULATED BY
CONVECTIVE OUTFLOWS)...AS WELL AS INDIVIDUAL LOW-AMPLITUDE WAVES
WILL ULTIMATELY DRIVE CONVECTIVE TRENDS AND TIMING DURING THIS
PERIOD.
RATZER
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 06Z...
* MVFR CIGS OVERSPREADING TERMINALS OVERNIGHT.
BMD
//DISCUSSION...UPDATED 06Z...
HIGH PRESSURE IS SETTLING OVER THE NORTHERN GREAT LAKES REGION
WHERE IT WILL REMAIN THROUGH THE TAF PERIOD PROVIDING LIGHT
NORTHEASTERLY WINDS. WINDS WILL LIKELY PICK UP SOME DURING THE DAY
THURSDAY AND MAY PUSH A LITTLE ABOVE 10 KT FOR A WHILE WITH AN
EXTRA PUSH FROM THE LAKE. THE ONLY MINOR CONCERN THIS FORECAST
PERIOD IS THE PRESENCE OF MVFR CIGS IN THE AREA WHICH ARE PROGGED
TO SPREAD WEST OVER THE TERMINALS TONIGHT. GUIDANCE MAY BE
OVERDOING THE LOW LEVEL MOISTURE SOME BUT THERE IS A BROAD AREA OF
STRATUS/FOG OVER LAKE MICHIGAN AS WELL AS PATCHY MVFR STRATUS OVER
N IN/SW MI THAT COULD POTENTIALLY SPREAD OVER THE TERMINALS
TONIGHT.
BMD
//ORD AND MDW CONFIDENCE...UPDATED 06Z...
* LOW CONFIDENCE IN MVFR CIGS/TIMING.
BMD
//OUTLOOK FOR ORD/MDW FOR 12Z FRIDAY-12Z WEDNESDAY...UPDATED 00Z...
FRIDAY AND SATURDAY...VFR.
SUNDAY THROUGH TUESDAY...MAINLY VFR WITH PERIODIC CHANCES FOR
THUNDERSTORMS.
MDB
&&
.MARINE...
246 AM CDT
HIGH PRESSURE EXTENDS FROM HUDSON BAY INTO THE CENTRAL GREAT LAKES
REGION WHERE IT WILL SLOWLY MIGRATE TO THE EASTERN LAKES BY
SATURDAY. IN THE MEANTIME...MODEST NORTHEAST TO EAST WINDS WILL
PREVAIL ACROSS LAKE MICHIGAN. WINDS ARE EXPECTED TO BE STRONGEST ON
THE SOUTH END OF THE LAKE WHERE IT MAY PEAK AROUND 15 TO 20 KT THIS
AFTERNOON. A WARM FRONT WILL LIFT ACROSS LAKE MICHIGAN THIS WEEKEND
WITH WINDS VEERING AROUND TO THE SOUTH BY SUNDAY. SOUTH TO SOUTHWEST
WINDS ARE THEN EXPECTED TO PERSIST THROUGH AROUND MIDWEEK WITH
ANOTHER COLD FRONT DROPS ACROSS THE LAKE.
BMD
&&
.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:
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[top]
Area Forecast Discussion
National Weather Service Lincoln IL
252 AM CDT Thu May 29 2014
.DISCUSSION...
ISSUED 250 AM CDT Thu May 29 2014
Weak frontal boundary centered just north of the I-70 corridor
early this morning. High pressure over the Great Lakes is
providing a northeast flow behind the front, which has dropped dew
points into the 50s from Galesburg to Bloomington northward, while
mid to upper 60s still prevail elsewhere. Still a fair amount of
cloud cover over the forecast area, some streaming north from the
ever-present upper low, now centered in south central Arkansas.
There were a few showers recently near the boundary which drifted
northwest due to that low, although these have now faded out.
Rain chances continue to be the primary forecast concern, with
next week`s chances a bit more challenging due to more model
disagreement.
SHORT TERM...Today through Saturday:
The frontal boundary should be quasi-stationary between the I-72
and I-70 corridors today, and will be the focus for the next round
of scattered showers and storms beginning around noon. Have had
some heavier pockets of rain recently, and with precipitable water
values around 1.5 to 1.6 inches, today shouldn`t be any different.
Severe weather threat remains minimal due to low shear values, but
cannot rule out some isolated funnels or land spouts similar to
yesterday, with the boundary overhead. Non-supercell tornado
parameter from the RAP model focuses on a couple areas, one along
the I-74 corridor just north of the main precipitation area, and
the other along I-72 near the boundary. Any such activity would be
most likely between noon and 4 pm.
The boundary will be pushed southward again tonight as an upper
high slides moves into the upper Mississippi Valley. As it will
not make it terribly far, the convection on Friday and Saturday will
be close by, but mostly out of our forecast area. Have maintained
some 20% PoP`s along the southern CWA border Friday afternoon, but
kept Saturday dry for now.
LONG TERM...Sunday through Wednesday:
Upper ridging breaks down during the weekend with more of a
southwest flow across the nation early next week, and the northern
jet stream along the Canadian border. Right now the ECMWF is the
odd model out in developing an upper low over the upper
Mississippi Valley which slowly drifts eastward through the Great
Lakes during the week, while the GFS, GEM and GFS ensembles have
more of periodic shortwave interaction between the two upper flows.
Sunday into early Monday are in most agreement with rain chances,
but trends widen after that. The ECMWF and the GEM to an extent
have the surface cyclone somewhat in agreement into Tuesday with
the cold front coming through, which would support the rain
chances continuing. Toward mid week, there is much more
uncertainty as the GFS never actually brings the front through and
holds it up near I-80, thus lingering rain chances, while the
ECMWF is dry. Have kept some PoP`s in for Wednesday for now, but
scaled them back from the initial blended guidance.
Geelhart
&&
.AVIATION...
ISSUED 1150 PM CDT Wed May 28 2014
The potential for some MVFR fog will increase after 08z for PIA
and BMI as those terminal sites received the most rain today.
Also, their dew point spreads are beginning to fall. BMI is 5 deg
and PIA is still 7 deg, but upstream trends show potential for
fog. La Salle/Peru is down to 4SM BR already. The other TAF sites
did not see much in the way of rain today, so any vis reduction
from fog should generally remain VFR.
Convection is forecast to develop north of the front tomorrow,
mainly from late morning through late afternoon. Storms could
reach as far north as BMI, but higher potential should remain
south of I-72. We included VCTS for storms only at SPI and DEC,
with VCSH for showers at CMI and BMI. PIA was left dry as they
should be far enough north of the cold front with dry low levels
filtering into N IL under high pressure.
Winds will remain light from the E-NE the rest of tonight.
Thursday morning, wind directions should veer to the east-
southeast during the day, but return to E-NE after 00z/7pm Thur.
Speeds are expected to generally remain less than 10kt under a
weak surface pressure gradient and wind speeds aloft.
Shimon
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS QUAD CITIES IA IL
1149 PM CDT WED MAY 28 2014
.SYNOPSIS...
ISSUED AT 310 PM CDT WED MAY 28 2014
12Z UA ANALYSIS HAS A WEAK UPPER LOW IN NORTHEAST IOWA WITH A
STRONGER UPPER LOW IN SOUTHWEST ARKANSAS. SEVERAL WEAK DISTURBANCES
WERE ROTATING AROUND THE LOWS. SATELLITE/RADAR TRENDS THROUGH MID
AFTERNOON SHOW DIURNAL CONVECTION ACROSS EASTERN IOWA AND NORTHERN
ILLINOIS THAT WAS SLOWLY ROTATING AROUND THE UPPER LOW IN EASTERN
IOWA.
18Z SFC ANALYSIS HAS AS WEAK LOW NEAR KAWG WITH A BOUNDARY EASTWARD
THROUGH CENTRAL ILLINOIS. DEW POINTS WERE IN THE 60S FROM THE GULF
COAST INTO THE MID MISSISSIPPI AND OHIO VALLEYS. DEW POINTS IN THE
40S AND 50S WERE ACROSS THE GREAT LAKES.
&&
.SHORT TERM...(THIS EVENING THROUGH THURSDAY)
ISSUED AT 310 PM CDT WED MAY 28 2014
RECENT RAP TRENDS INDICATE THE EFFECTIVE BOUNDARY WILL REMAIN NEARLY
STATIONARY FROM ABOUT KAWG TO NEAR KPNT THROUGH LATE AFTERNOON. WITH
THE WEAK UPPER LOW JUST WEST OF THE QUAD CITIES...CONVECTION WILL
DRIFT SLOWLY SOUTH WEST OF THE MISSISSIPPI AND SLOWLY NORTH EAST OF
THE MISSISSIPPI.
DUE TO THE SLOW MOVEMENT OF STORMS...LOCALLY HEAVY RAINFALL WILL BE
SEEN.
BY EARLY EVENING AND CONTINUING THROUGH SUNSET CONVECTION WILL
SLOWLY DISSIPATE WITH CONVECTION BECOMING VERY ISOLATED BY MIDNIGHT.
DURING THE EVENING THE BOUNDARY WILL SLOWLY DRIFT SOUTH AND WILL BE
THE FOCUS FOR MAINTAINING ISOLATED CONVECTION PAST SUNSET.
AFTER MIDNIGHT MOST OF THE AREA IS EXPECTED TO REMAIN DRY AS THE
BOUNDARY CONTINUES A SLOW DRIFT TO THE SOUTH. ANY REMAINING RAIN
WILL BE CONFINED TO AREAS CLOSE TO THE FRONT.
THURSDAY MORNING THERE MAY BE SOME LINGERING SHOWERS ACROSS THE FAR
SOUTH CLOSE TO THE BOUNDARY WHILE THE REMAINDER OF THE AREA IS DRY.
NEW DIURNAL CONVECTION IS EXPECTED TO DEVELOP BY LATE MORNING AND
CONTINUE THROUGH THURSDAY AFTERNOON SOUTH OF I-80. THIS NEW
CONVECTION IS EXPECTED TO BE ISOLATED IN NATURE BUT MAY BE MORE
SCATTERED BETWEEN KBRL AND KUIN.
.LONG TERM...(THURSDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 310 PM CDT WED MAY 28 2014
SURFACE AND UPPER RIDGING WILL MOVE THROUGH THE REGION LATE THIS
WEEK KEEPING DRY WEATHER OVER THE AREA. THUNDERSTORM CHANCES WILL
RETURN TO THE FORECAST OVER THE WEEKEND AND EARLY NEXT WEEK AS LOW
LEVEL MOISTURE INCREASES BEHIND THE DEPARTING RIDGE. THE BEST CHANCE
OF THUNDERSTORMS WILL BE TUESDAY INTO WEDNESDAY AS A COLD FRONT MOVES
SLOWLY THROUGH THE REGION.
THURSDAY NIGHT INTO FRIDAY NIGHT LESS HUMID CONDITIONS WILL BE IN PLACE
WITH A SURFACE HIGH OVER THE WESTERN GREAT LAKES FEEDING DRY AIR
INTO THE REGION. TEMPERATURES SHOULD BE SEASONAL WITH HIGHS FRIDAY
IN THE LOW 80S AND LOWS THURSDAY AND FRIDAY MORNINGS IN THE MID 50S
TO MID 60S.
THUNDERSTORM CHANCES CREEP BACK INTO THE FORECAST FOR THE WEEKEND AS
THE UPPER AND SURFACE RIDING MOVE EAST ALLOWING MOIST RETURN FLOW
TO SET UP. FOR NOW WITHOUT ANY OBVIOUS FORCING MECHANISMS SHOWN IN
THE MODEL SOLUTIONS KEPT POPS IN THE LOW CHANCE CATEGORY.
MODEL SOLUTIONS SHOW A BETTER THREAT OF THUNDERSTORMS EARLY NEXT
WEEK WITH A PERSISTENT SOUTHWEST TROF IN PLACE AND A SERIES OF S/WS
EJECTING OUT OF THE TROF INTO THE PLAINS AND UPPER MIDWEST. THIS
WILL SEND A SLOW MOVING COLD FRONT THROUGH THE REGION TUESDAY INTO
WEDNESDAY. THE GFS/ECMWF GENERALLY AGREE ON THE OVER ALL SYNOPTIC
PATTERN EARLY NEXT WEEK BUT HAVE DIFFERENT TAKES ON HANDLING THE
S/WS IN THE SOUTHWEST FLOW AND THE SURFACE FRONT. THE GFS BRINGS
OUT A MAIN S/W MONDAY NIGHT AND TUESDAY WHICH PUSHES THE COLD FRONT
SOUTHEAST OF THE FORECAST AREA BY WEDNESDAY. THE ECMWF IS MORE
FRAGMENTED WITH THE S/WS AND STALLS THE FRONT OVER OR JUST SOUTH OF
THE CWA BY LATE TUESDAY. EITHER SOLUTION THOUGH SUPPORTS AN ACTIVE
PATTERN.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z THURSDAY NIGHT)
ISSUED AT 1140 PM CDT WED MAY 28 2014
DRIER AIR ON NORTHEAST WINDS AROUND 10 KTS SHOULD LIMIT FOG TO VERY
PATCHY (2-6SM) NATURE AND MAINLY ACROSS THE FAR SOUTHERN CWA
WITHIN BETTER LOW LEVEL MOISTURE OR IN AREAS THAT RECEIVED RAIN
WED PM. OTHERWISE...VFR CONDITIONS EXPECTED THROUGH THE TAF CYCLE.
A FEW SHOWERS AND STORMS EXPECTED TO DEVELOP YET AGAIN THURSDAY PM
BUT MAINLY WELL SOUTH OF I-80 WITHIN RESIDUAL MOIST AXIS AND ATTENDANT
TO UPPER DISTURBANCE...WITH ANY ACTIVITY DISSIPATING TOWARD SUNSET.
&&
.DVN WATCHES/WARNINGS/ADVISORIES...
IA...NONE.
IL...NONE.
MO...NONE.
&&
$$
SYNOPSIS...08
SHORT TERM...08
LONG TERM...DLF
AVIATION...05
AREA FORECAST DISCUSSION...UPDATED
NWS NORTH PLATTE NE
1223 AM CDT THU MAY 29 2014
.SYNOPSIS...
ISSUED AT 356 PM CDT WED MAY 28 2014
THE CENTRAL PLAINS ARE UNDERNEATH A LARGE 500HPA RIDGE AHEAD OF AN
INCOMING TROUGH AFFECTING THE PACIFIC NORTHWEST. THE AREA OF LOW
PRESSURE ALOFT HAS MOVED INTO THE MISSISSIPPI DELTA REGION. AT THE
SURFACE...ONE LOW PRESSURE SYSTEM EXISTS ACROSS THE FAR NORTHERN
PLAINS AND ONE OVER THE LOWER GREAT LAKES. HIGH PRESSURE SITUATED IN
SOUTHERN COLORADO COMBINED WITH THE UPPER LEVEL RIDGE ARE PROVIDING
HOT AND MAINLY DRY CONDITIONS TO NEBRASKA.
&&
.SHORT TERM...(THIS EVENING THROUGH THURSDAY)
ISSUED AT 356 PM CDT WED MAY 28 2014
ISOLATED THUNDERSTORMS ARE POSSIBLE THIS AFTERNOON ACROSS PORTIONS
OF THE WESTERN SANDHILLS AND SOUTHWEST NEBRASKA. THE HRRR MODEL HAS
BEEN HINTING AT DEVELOPMENT FOR SEVERAL RUNS AND A CUMULUS FIELD
SHOWED UP ON VISIBLE SATELLITE EARLY AFTERNOON. IN ADDITION...MANY
LOCATIONS HAVE REACHED THE CONVECTIVE TEMPERATURE BASED ON THE
28/12Z KLBF RAOB. ANY THUNDERSTORM SHOULD DISSIPATE SHORTLY AFTER
SUNSET AS THE CAP STRENGTHENS. TEMPERATURE TRENDS FOR OVERNIGHT LOWS
AND THURSDAY HIGHS LOOKED GOOD FROM PREVIOUS FORECAST. ONLY CHANGES
WERE DROPPED A DEGREE OR SO TONIGHT BASED ON GUIDANCE AND THE DEW
POINT FORECAST...AND RAISED A DEGREE THURSDAY FOR CONTINUED SUNSHINE
AND SOUTH WINDS. MOISTURE ADVECTS INTO THE AREA THURSDAY AHEAD OF
THE NEXT WEATHER SYSTEM...AS SURFACE DEW POINTS REACH THE LOWER 60S
ACROSS NORTH CENTRAL NEBRASKA. ANY PRECIPITATION WILL HOLD OFF UNTIL
THE LONG TERM FORECAST PERIOD.
.LONG TERM...(THURSDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 356 PM CDT WED MAY 28 2014
AN ACTIVE WEATHER PATTERN WILL BE ONGOING ACROSS THE CENTRAL
PLAINS LATER THIS WEEK INTO NEXT WEEK.
THE UPPER LEVEL LOW CURRENTLY OVER ARKANSAS/LOUISIANA AND EASTERN
TEXAS WILL SEE LITTLE MOVEMENT OVER THE NEXT SEVERAL DAYS AS IT
BECOMES CUTOFF FROM THE GENERAL FLOW AND REMAINS NEARLY STATIONARY
UNDER THE RIDGE WHICH WILL BE CENTERED OVER THE NORTHERN PLAINS
AND UPPER MISSISSIPPI RIVER VALLEY AT 00Z FRIDAY. OVER THE NEXT
SEVERAL DAYS THE RIDGE AXIS WILL MOVE EASTWARD AS A STRONG TROUGH
MOVES ONSHORE OVER THE WEST COAST ON SATURDAY. THIS PATTERN SHIFT
WILL BRING STRONGER UPPER LEVEL FLOW TO THE REGION...ALONG WITH A
MULTITUDE OF WEAK BOUTS OF SHORTWAVE ENERGY FROM THE SOUTHWEST
FLOW INTO THE CENTRAL PLAINS.
ALTHOUGH THE MODELS ARE IN GOOD CONSENSUS WITH THE GENERAL
PATTERN...THERE IS SOME DISCONTINUITY ON THE TRACK OF THE
SHORTWAVES AS WELL AS THE MOVEMENT OF THE LONGWAVE TROUGH OUT WEST
INTO NEXT WEEK. THEREFORE...USED A MODEL CONSENSUS FOR MUCH OF THE
LONG TERM PORTION OF THE FORECAST AS CONFIDENCE ISN/T REAL HIGH ON
TIMING OF PRECIPITATION CHANCES.
STARTING THURSDAY EVENING...RIDGING IS STILL WELL IN PLACE ACROSS
THE CENTRAL PLAINS AND WITH THE MID-LEVEL FLOW NORTH-NORTHWEST
CONVECTION DEVELOPING ACROSS NORTHERN COLORADO AND THE WESTERN
PANHANDLE MAY JUST SKIRT THE NORTHWEST PART OF THE FORECAST AREA.
SO LIMITED THE CHANCES FOR SHOWERS AND STORMS TO PORTIONS OF
SHERIDAN COUNTY.
DURING THE DAY ON FRIDAY...SHOWER AND STORM CHANCES WILL AGAIN BE
CONFINED TO AREAS OVER THE WESTERN PART OF THE FORECAST
AREA...MAINLY THE PANHANDLE AND THE WESTERN SANDHILLS AS
CONVECTION SHOULD DEVELOP OVER THE HIGHER ELEVATIONS ACROSS
COLORADO AND THE WESTERN PANHANDLE WHERE THERE WILL BE BETTER
SHORTWAVE ENERGY...ALONG WITH SOME UPSLOPE FLOW AND A FOCUS OF
MOISTURE TRANSPORT. THE LOW LEVEL JET WILL VEER INTO THE EVENING
WHICH WILL THEN SUPPORT STORMS TRANSITIONING EAST ACROSS NORTHERN
NEBRASKA AND INTO SOUTH DAKOTA. PRECIPITATION CHANCES HAVE BEEN
TRENDED IN THIS DIRECTION.
ON SATURDAY A FAIRLY STRONG SHORTWAVE TROUGH IS EXPECTED TO MOVE
ACROSS THE NORTHERN PLAINS AND INTO NORTHERN NEBRASKA. THIS WILL
PUSH A COLD FRONT INTO THE FORECAST AREA THROUGH THE DAY HOWEVER
IT DOESN/T LOOK TO PROGRESS VERY FAR EAST. EXPECTING TO GET
DEVELOPMENT ALONG THE FRONT SATURDAY AFTERNOON. ANY STORMS
DEVELOPING ON SATURDAY COULD GET STRONG TO SEVERE AS THE INCREASE
IN THE UPPER LEVEL FLOW WILL HELP TO STRENGTHEN THE DEEP LAYER
SHEAR TO GET STORMS HAVE THE POTENTIAL TO BECOME MORE ORGANIZED.
BEYOND SATURDAY IS WHEN THE DIFFERENCES IN TIMING OF ANY SHORTWAVE
ENERGY MOVING THROUGH THE AREA BECOME MORE APPARENT. SO THE
CHANCES FOR SHOWERS AND THUNDERSTORMS FOR MUCH OF THE AREA
CONTINUE DAILY THROUGH THE EARLY PORTIONS OF NEXT WEEK. ALTHOUGH
SEVERE STORMS ARE NOT OUT OF THE QUESTION ANY DAY AS THERE SHOULD
BE DECENT INSTABILITY AND WIND SHEER EACH DAY...THERE ISN/T A PERIOD
THAT LOOKS BETTER THAN OTHERS TO HIGHLIGHT THE CHANCES FOR SEVERE
STORMS.
AS FOR TEMPERATURES...FRIDAY WILL BE ANOTHER WARM DAY WITH HIGHS
IN THE MID TO UPPER 80S. ON SATURDAY...THE NORTHWEST MAY BE A BIT
COOLER IN THE 70S AS THE COLD FRONT MOVES THROUGH THAT
AREA...WITH THE REMAINDER OF THE FORECAST AREA IN THE 80S. THEN
THE REST OF THE FORECAST PERIOD HAS HIGHS IN THE 70S AND 80S AS
SHOWERS/STORMS/CLOUDS WILL PLAGUE MUCH OF THE AREA KEEPING
TEMPERATURES IN CHECK. AS FOR LOWS...DEWPOINTS IN THE UPPER 40S TO
LOW 60S THROUGHOUT THE PERIOD WILL KEEP TEMPERATURES FROM FALLING
TOO FAR AND WILL STAY SLIGHTLY ABOVE NORMAL.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z THURSDAY NIGHT)
ISSUED AT 1222 AM CDT THU MAY 29 2014
OVER THE NEXT 24 HOURS...EXPECT CLEAR SKIES AT THE KLBF AND KVTN
TERMINALS. THE EXCEPTION MAY BE SOME SCATTERED MID LEVEL CLOUDINESS
AON 8000 FT AGL THURSDAY AFTERNOON. WINDS WILL BE FROM THE SOUTHEAST
AT AROUND 10 KTS OVERNIGHT TONIGHT AND THURSDAY EVENING. ON
THURSDAY...WIND SPEEDS OF 10 TO 20 KTS ARE EXPECTED WITH SOME GUSTS
APPG 25 KTS THURSDAY AFTERNOON AT THE KVTN TERMINAL.
&&
.LBF WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...DS
SHORT TERM...DS
LONG TERM...BROOKS
AVIATION...CDC
AREA FORECAST DISCUSSION
NWS RALEIGH NC
250 AM EDT THU MAY 29 2014
.SYNOPSIS...A COLD FRONT WILL MOVE SOUTHWEST THROUGH CENTRAL NORTH
CAROLINA TODAY...THEN STALL OUT SOUTH OF THE AREA ON FRIDAY. HIGH
PRESSURE WILL EXTEND INTO THE REGION FROM THE NORTH OVER THE WEEKEND.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 920 PM WEDNESDAY...
PRIMARY CHANGE THIS EVENING IS A REORIENTATION OF PRECIP CHANCES
ACROSS THE CWA TO INCREASE THEM ACROSS THE NORTHEAST QUARTER OF THE
CWA AND DECREASE THEM ELSEWHERE. AS OF 9 PM THE BACKDOOR SURFACE
FRONT EXTENDED FROM JUST SOUTH OF CHI ACROSS FAR NRN IN/OH AND SW
PA/DC/DELMARVA. AS ONE MIGHT EXPECT WITHIN A REGIME OF MARGINAL TO
MODERATE INSTABILITY AND VERY WEAK SHEAR... THE LATEST SURFACE
ANALYSIS SHOWS NUMEROUS WEAK BOUNDARIES AND CONVECTIVE OUTFLOWS
ACROSS THE REGION... THE MOST PROFOUND OF WHICH NOW STRETCHES FROM
WEST CENTRAL VA SE TO SE VA AND NE NC WITH NUMEROUS SHOWERS AND
STORMS AND THE ASSOCIATED COLD POOL PROPAGATING GENERALLY
SOUTHWARD... OUT AHEAD OF THE SYNOPTIC FRONT. EARLIER HRRR RUNS
TODAY HAVE NOT DONE VERY WELL BUT THE LATEST HRRR RUN APPEARS TO BE
HANDLING THE ONGOING CONVECTION TO OUR NNE WELL... AND IT PROGRESSES
THIS ACTIVITY SOUTHWARD AND SE OVER THE NORTHEAST CWA... IN LINE
WITH EXTRAPOLATION OF EXISTING FEATURES. THE AIR MASS IN THIS REGION
REMAINS MODERATELY UNSTABLE WITH MLCAPE VALUES OF 1500-2000 J/KG
ACCORDING TO THE SPC MESOANALYSIS... AND WHILE CINH IS STARTING TO
CREEP UP... LAPSE RATES REMAIN HIGH ENOUGH WITH REMAINING ELEVATED
CAPE TO SUPPORT THE ONGOING CONVECTION AS IT TRANSLATES INTO THE
CENTRAL NC. HAVE RAISED POPS TO SCATTERED FROM RALEIGH TO THE NORTH
AND EAST... PUSHING SOUTHEAST THROUGH THE NIGHT... WITH ISOLATED
POPS SURROUNDING THIS AREA... AND LITTLE TO NO POP OVER THE WRN AND
SW CWA. WITH A TREND TOWARD MOSTLY CLOUDY SKIES... EXPECT LOWS OF 66-
71. -GIH
&&
.SHORT TERM /THURSDAY AND FRIDAY/...
AS OF 245 PM WEDNESDAY...
THE BACKDOOR COLD FRONT SLIDING TOWARD CENTRAL NC FROM THE NORTH
WILL STALL OUT AROUND THE VA/NC BORDER. SURFACE CONVERGENCE BETWEEN
THE HIGH TO THE NE AND LOW TO THE SW...AND THE RESULTANT MOISTURE
AND TEMPERATURE BOUNDARIES...WILL RESULT IN INCREASED CHANCES FOR
CONVECTION...ESPECIALLY ACROSS THE SOUTH WHERE THE BEST MOISTURE AND
HIGHEST TEMPS ARE EXPECTED. THE BEST UPPER LEVEL FORCING WILL OCCUR
AROUND/AFTER 00Z FRIDAY AS SHORTWAVE ENERGY MOVES AROUND THE BASE OF
THE UPPER LEVEL TROUGH AND SWINGS THROUGH THE AREA. SHEAR AND
INSTABILITY PARAMETERS ARE EXPECTED TO BE SIMILAR TO TUESDAY AND
WEDNESDAY...WITH PWATS IN THE 1.50-1.75 INCH RANGE. THUS...AN
ISOLATED SEVERE STORM OR TWO AND HEAVY RAIN CANNOT BE RULED
OUT...WITH THE BEST CHANCES ACROSS THE SOUTH. THE FRONT WILL LINGER
NEAR THE SOUTHERN PORTION OF THE FORECAST AREA ON FRIDAY...BEFORE
BEING PUSHED EVEN FURTHER SOUTH OVER THE WEEKEND BY HIGH PRESSURE
BUILDING DOWN OUT OF THE NORTHEAST. GOOD MOISTURE WILL REMAIN OVER
THE AREA (PWAT VALUES NEAR 1.25-1.75 INCHES... HIGHEST ACROSS THE
SOUTH) BEFORE DRIER AIR FILTERS IN LATE FRIDAY INTO SATURDAY. AS A
RESULT... DECENT PRECIP CHANCES WILL ONCE AGAIN OCCUR ACROSS THE
AREA ON FRIDAY (HIGHEST ACROSS THE SOUTH IN THE VICINITY OF THE
FRONT AND BEST DESTABILIZATION). TEMPS WILL GENERALLY BE IN THE
UPPER 70S TO LOWER 80S.
&&
.LONG TERM /FRIDAY NIGHT THROUGH WEDNESDAY/...
AS OF 250 AM THURSDAY...
MODEL CONSENSUS WOULD BRING CLEARING FROM NORTHEAST TO SOUTHWEST
ACROSS CENTRAL NC FRIDAY NIGHT AND SATURDAY MORNING. THIS OCCURS AS
DRIER AIR IS DRIVEN INTO THE REGION COURTESY OF THE STRENGTHENING
(1030+ MB) SURFACE HIGH PRESSURE LOCATED TO OUR NORTH. HOWEVER...
THERE SHOULD STILL BE ENOUGH OF AN EASTERLY UPSLOPE TYPE COMPONENT
TO THE FLOW TO KEEP VARIABLY CLOUDY SKIES INTO SATURDAY OR SATURDAY
NIGHT OVER PORTIONS OF THE WESTERN PIEDMONT. LITTLE IF ANY CHANCE OF
SHOWERS IS NOTED IN THE LATEST MODEL RUNS PAST FRI EVENING. WE WILL
MAINTAIN OUR ONGOING FORECAST OF MOSTLY SUNNY/MOSTLY CLEAR SAT-
MON... EXCEPT VARIABLY CLOUDY FRI NIGHT AND SATURDAY FAR WESTERN
PIEDMONT. LOWS IN THE 50S NE TO NEAR 60 SW SATURDAY AND SUNDAY.
HIGHS GENERALLY 78-83.
FOR MONDAY AND BEYOND... THERE IS STILL NOT MUCH OF AN INDICATION OF
A WIDESPREAD SHOWER OR THUNDERSTORM THREAT THROUGH AT LEAST MIDWEEK.
GRADUAL WARMING TO HOT BY WEDNESDAY AS HIGHS RETURN INTO THE 80S
(SOME LOWER 90S BY WED). LOWS INCREASE INTO THE 60S. THE ONLY
MENTION OF RAIN CHANCES WILL BE A SLIGHT CHANCE OF PM SHOWERS/STORMS
WED.
&&
.AVIATION /06Z THURSDAY THROUGH MONDAY/...
AS OF 200 AM THURSDAY...
24-HR TAF PERIOD: VFR CONDITIONS WILL PREVAIL AT MOST TERMINALS
THROUGH THE REMAINDER OF THE MORNING. IFR CEILINGS OBSERVED OVER
SOUTHEAST VA AND NORTHEAST NC AT 06Z ARE EXPECTED TO MOVE SOUTHWEST
INTO THE NORTHEAST COASTAL PLAIN BY ~12Z...AND WILL LIKELY AFFECT
THE KRWI TERMINAL AROUND THAT TIME...SLOWLY LIFTING TO MVFR BY NOON.
IT IS POSSIBLE THAT THE KRDU TERMINAL COULD SEE A PERIOD OF MVFR
CEILINGS BETWEEN 12-16Z...THOUGH UNCERTAINTY IS SUFFICIENT ENOUGH TO
PRECLUDE MENTION AT THIS TIME. OTHERWISE...EXPECT SCATTERED TO
NUMEROUS SHOWERS AND THUNDERSTORMS TO AFFECT THE INT/GSO/RDU/FAY
TERMINALS THIS AFTERNOON AS A BACK DOOR COLD FRONT CONTINUES TO MOVE
SOUTHWEST INTO CENTRAL NC. EXPECT IFR/LIFR CEILINGS TO DEVELOP ON
THE COOL SIDE OF THE BACK DOOR FRONT BY THE END OF THE TAF PERIOD
(TONIGHT) AT ALL TERMINALS.
LOOKING AHEAD: SUB-VFR CEILINGS ARE LIKELY TO PERSIST IN MOST AREAS
FRIDAY INTO FRIDAY NIGHT. EXPECT VFR CONDITIONS TO RETURN SAT-MON AS
DRY HIGH PRESSURE EXTENDS INTO THE REGION FROM THE NORTH. -VINCENT
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...VINCENT
NEAR TERM...HARTFIELD
SHORT TERM...KC
LONG TERM...32
AVIATION...VINCENT
AREA FORECAST DISCUSSION
NWS RALEIGH NC
216 AM EDT THU MAY 29 2014
.SYNOPSIS...A BACK DOOR COLD FRONT WILL MOVE SOUTHWEST THROUGH
CENTRAL NORTH CAROLINA TODAY...THEN STALL OUT SOUTH OF THE AREA ON
FRIDAY. HIGH PRESSURE WILL EXTEND INTO THE REGION FROM THE NORTH
OVER THE WEEKEND.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 920 PM WEDNESDAY...
PRIMARY CHANGE THIS EVENING IS A REORIENTATION OF PRECIP CHANCES
ACROSS THE CWA TO INCREASE THEM ACROSS THE NORTHEAST QUARTER OF THE
CWA AND DECREASE THEM ELSEWHERE. AS OF 9 PM THE BACKDOOR SURFACE
FRONT EXTENDED FROM JUST SOUTH OF CHI ACROSS FAR NRN IN/OH AND SW
PA/DC/DELMARVA. AS ONE MIGHT EXPECT WITHIN A REGIME OF MARGINAL TO
MODERATE INSTABILITY AND VERY WEAK SHEAR... THE LATEST SURFACE
ANALYSIS SHOWS NUMEROUS WEAK BOUNDARIES AND CONVECTIVE OUTFLOWS
ACROSS THE REGION... THE MOST PROFOUND OF WHICH NOW STRETCHES FROM
WEST CENTRAL VA SE TO SE VA AND NE NC WITH NUMEROUS SHOWERS AND
STORMS AND THE ASSOCIATED COLD POOL PROPAGATING GENERALLY
SOUTHWARD... OUT AHEAD OF THE SYNOPTIC FRONT. EARLIER HRRR RUNS
TODAY HAVE NOT DONE VERY WELL BUT THE LATEST HRRR RUN APPEARS TO BE
HANDLING THE ONGOING CONVECTION TO OUR NNE WELL... AND IT PROGRESSES
THIS ACTIVITY SOUTHWARD AND SE OVER THE NORTHEAST CWA... IN LINE
WITH EXTRAPOLATION OF EXISTING FEATURES. THE AIR MASS IN THIS REGION
REMAINS MODERATELY UNSTABLE WITH MLCAPE VALUES OF 1500-2000 J/KG
ACCORDING TO THE SPC MESOANALYSIS... AND WHILE CINH IS STARTING TO
CREEP UP... LAPSE RATES REMAIN HIGH ENOUGH WITH REMAINING ELEVATED
CAPE TO SUPPORT THE ONGOING CONVECTION AS IT TRANSLATES INTO THE
CENTRAL NC. HAVE RAISED POPS TO SCATTERED FROM RALEIGH TO THE NORTH
AND EAST... PUSHING SOUTHEAST THROUGH THE NIGHT... WITH ISOLATED
POPS SURROUNDING THIS AREA... AND LITTLE TO NO POP OVER THE WRN AND
SW CWA. WITH A TREND TOWARD MOSTLY CLOUDY SKIES... EXPECT LOWS OF 66-
71. -GIH
&&
.SHORT TERM /THURSDAY AND THURSDAY NIGHT/...
AS OF 245 PM WEDNESDAY...
THE BACKDOOR COLD FRONT SLIDING TOWARD CENTRAL NC FROM THE NORTH
WILL STALL OUT AROUND THE VA/NC BORDER. SURFACE CONVERGENCE BETWEEN
THE HIGH TO THE NE AND LOW TO THE SW...AND THE RESULTANT MOISTURE
AND TEMPERATURE BOUNDARIES...WILL RESULT IN INCREASED CHANCES FOR
CONVECTION...ESPECIALLY ACROSS THE SOUTH WHERE THE BEST MOISTURE AND
HIGHEST TEMPS ARE EXPECTED. THE BEST UPPER LEVEL FORCING WILL OCCUR
AROUND/AFTER 00Z FRIDAY AS SHORTWAVE ENERGY MOVES AROUND THE BASE OF
THE UPPER LEVEL TROUGH AND SWINGS THROUGH THE AREA. SHEAR AND
INSTABILITY PARAMETERS ARE EXPECTED TO BE SIMILAR TO TUESDAY AND
WEDNESDAY...WITH PWATS IN THE 1.50-1.75 INCH RANGE. THUS...AN
ISOLATED SEVERE STORM OR TWO AND HEAVY RAIN CANNOT BE RULED
OUT...WITH THE BEST CHANCES ACROSS THE SOUTH.
&&
.LONG TERM /FRIDAY THROUGH WEDNESDAY/...
AS OF 245 PM WEDNESDAY...
THE FRONT WILL LINGER NEAR THE SOUTHERN PORTION OF THE FORECAST AREA
ON FRIDAY...BEFORE BEING PUSHED EVEN FURTHER SOUTH OVER THE WEEKEND
BY HIGH PRESSURE BUILDING DOWN OUT OF THE NORTHEAST. GOOD MOISTURE
WILL REMAIN OVER THE AREA (PWAT VALUES NEAR 1.25-1.75 INCHES...
HIGHEST ACROSS THE SOUTH) BEFORE DRIER AIR FILTERS IN LATE FRIDAY
INTO SATURDAY. AS A RESULT... DECENT PRECIP CHANCES WILL ONCE AGAIN
OCCUR ACROSS THE AREA ON FRIDAY (HIGHEST ACROSS THE SOUTH IN THE
VICINITY OF THE FRONT AND BEST DESTABILIZATION). TEMPS WILL
GENERALLY BE IN THE UPPER 70S TO LOWER 80S.
THEN...FAIRLY STRONG HIGH PRESSURE (~1025 MB) WILL BUILD DOWN THE
EAST COAST OVER THE WEEKEND...PUSHING THE BOUNDARY EVEN FURTHER
SOUTH. THIS WILL VIRTUALLY BRING AN END TO OUR PRECIP CHANCES AS
STABLE NORTHEASTERLY FLOW DOMINATES. HIGH PRESSURE WILL THEN
DOMINATE THROUGH EARLY NEXT WEEK...SHIFTING OFFSHORE BY TUESDAY.
THEREFORE...AM EXPECTING THE AREA TO BE MOSTLY DRY...WITH MAYBE SOME
DIURNAL TYPE PRECIP RETURNING TUESDAY INTO WEDNESDAY AS MOISTURE
GRADUALLY INCREASES IN THE INCREASING RETURN FLOW...ESPECIALLY
ACROSS THE WESTERN PORTIONS OF THE FORECAST AREA. TEMPS WILL BE
SLIGHTLY BELOW NORMAL FOR THE WEEKEND...BEFORE GRADUALLY MODERATING
NEXT WEEK TO BACK TO ABOVE NORMAL BY TUESDAY.
&&
.AVIATION /06Z THURSDAY THROUGH MONDAY/...
AS OF 200 AM THURSDAY...
24-HR TAF PERIOD: VFR CONDITIONS WILL PREVAIL AT MOST TERMINALS
THROUGH THE REMAINDER OF THE MORNING. IFR CEILINGS OBSERVED OVER
SOUTHEAST VA AND NORTHEAST NC AT 06Z ARE EXPECTED TO MOVE SOUTHWEST
INTO THE NORTHEAST COASTAL PLAIN BY ~12Z...AND WILL LIKELY AFFECT
THE KRWI TERMINAL AROUND THAT TIME...SLOWLY LIFTING TO MVFR BY NOON.
IT IS POSSIBLE THAT THE KRDU TERMINAL COULD SEE A PERIOD OF MVFR
CEILINGS BETWEEN 12-16Z...THOUGH UNCERTAINTY IS SUFFICIENT ENOUGH TO
PRECLUDE MENTION AT THIS TIME. OTHERWISE...EXPECT SCATTERED TO
NUMEROUS SHOWERS AND THUNDERSTORMS TO AFFECT THE INT/GSO/RDU/FAY
TERMINALS THIS AFTERNOON AS A BACK DOOR COLD FRONT CONTINUES TO MOVE
SOUTHWEST INTO CENTRAL NC. EXPECT IFR/LIFR CEILINGS TO DEVELOP ON
THE COOL SIDE OF THE BACK DOOR FRONT BY THE END OF THE TAF PERIOD
(TONIGHT) AT ALL TERMINALS.
LOOKING AHEAD: SUB-VFR CEILINGS ARE LIKELY TO PERSIST IN MOST AREAS
FRIDAY INTO FRIDAY NIGHT. EXPECT VFR CONDITIONS TO RETURN SAT-MON AS
DRY HIGH PRESSURE EXTENDS INTO THE REGION FROM THE NORTH. -VINCENT
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...VINCENT
NEAR TERM...HARTFIELD
SHORT TERM...KC
LONG TERM...KRD
AVIATION...VINCENT
AREA FORECAST DISCUSSION
NWS BISMARCK ND
1220 AM CDT THU MAY 29 2014
.UPDATE...
ISSUED AT 1220 AM CDT THU MAY 29 2014
MAIN ADJUSTMENT TO THE FORECAST WAS TO REMOVE THE SEVERE
THUNDERSTORM WORDING FOR TONIGHT IN THE WEST. AREA RADARS HAVE
SHOWN A DECREASING TREND IN THE STORM INTENSITY AS THE CONVECTION
MOVES INTO WESTERN NORTH DAKOTA. THE LATEST SHORT TERM MODELS
SUGGEST THE CONVECTION WILL LIKELY PERSIST FOR ANOTHER SEVERAL
HOURS...BUT SHOULD GRADUALLY WANE LATER THIS MORNING.
UPDATE ISSUED AT 1002 CDT WED MAY 28 2014
QUICK UPDATE AGAIN TO BETTER REFLECT LIGHT RAIN ACROSS FAR
WEST...WHERE POPS WERE TOO LOW. MAINTAINED CONVECTIVE CHANCES AS
PREVIOUSLY SHOWN AND CONTINUING TO WATCH CONVECTION IN EAST
CENTRAL MT WHICH HAS STRENGTHENED IN PAST HALF HOUR.
UPDATE ISSUED AT 943 PM CDT WED MAY 28 2014
MAIN CHANGES WERE ADJUSTMENTS TO POPS. AS MENTIONED IN SPC MCD
ISSUED A FEW MINUTES AGO CONVECTION ACROSS EAST CENTRAL MONTANA IS
LESS ORGANIZED THAN THE CLUSTER OF STORMS ACROSS NORTH CENTRAL
MONTANA. HI RES MODELS CONTINUE TO HAVE CHALLENGES WITH ONGOING
CONVECTION. HRRR INITIALIZED WELL WITH 01Z RUN...BUT APPEARS TO
OVERDUE EXPANSION OF CONVECTION IN SUBSEQUENT HOURS. RAP TIMING
APPEARS TO BE SLOWER AND MORE ACCURATE. BOTH MODELS HINT AT
STRONGER CLUSTER IN NORTH CENTRAL MONTANA MOVING NORTHEAST INTO
CANADA. GIVEN THESE TRENDS...HAVE LOWERED POPS NEXT COUPLE HOURS
AND MAINTAINED BEST CHANCE ACROSS NORTHWEST ND. DID INTRODUCE SOME
POPS ACROSS SOUTHWEST BASED ON WEAK RETURNS APPROACHING ON BOWMAN
RADAR.
UPDATE ISSUED AT 713 PM CDT WED MAY 28 2014
MAIN UPDATE CONCERN IS CONVECTIVE POTENTIAL TONIGHT. CURRENTLY
MOST OF MONTANA IS IN A SEVERE THUNDERSTORM WATCH. RADAR MOSAIC
SHOWS THUNDERSTORMS STILL WELL WEST OF NORTH DAKOTA. ATMOSPHERE
STILL WELL CAPPED AND HI-RES MODELS /RAP AND HRRR/ ARE TOO FAR
EAST WITH CONVECTION COMPARED TO CURRENT RADAR. HAVE TRIMMED BACK
POPS FOR EARLY EVENING AND WILL CONTINUE TO MONITOR TRENDS FOR
NEXT UPDATE. LATEST BUFR SOUNDINGS FOR KISN ALSO SHOW SUBSTANTIAL
CAP IN PLACE THROUGH THE EVENING. 18Z NAM KEEPS CWA DRY OVERNIGHT
WHILE GFS SPREADS SOME SHOWERS/THUNDERSTORMS INTO THE WEST BY 06Z.
ALSO UPDATED HOURLY GRIDS TO ACCOUNT FOR LESS CLOUD COVER AND
SLIGHT TEMP ADJUSTMENTS FOR WEST WHICH WAS RUNNING SLIGHTLY COOLER
THAN NORMAL AND THE EAST WHICH WAS A LITTLE WARMER THAN CURRENT
FORECAST.
&&
.SHORT TERM...(THIS AFTERNOON THROUGH THURSDAY)
ISSUED AT 321 PM CDT WED MAY 28 2014
THE MAIN CHALLENGE FOR THE PERIOD WILL BE DETERMINING THE SEVERE
POTENTIAL OVER EXTREME NORTHWESTERN NORTH DAKOTA TONIGHT...AND AGAIN
OVER WESTERN AND NORTH CENTRAL NORTH DAKOTA LATE THURSDAY AFTERNOON.
MSAS ANALYSIS INDICATES A SURFACE LOW DEEPENING OVER CENTRAL MONTANA
THIS AFTERNOON...WHICH IS SERVING TO INCREASE THE LOW-LEVEL JET
OVER WESTERN NORTH DAKOTA. THE INCREASING LOW-LEVEL MOISTURE FEED IS
INCREASING SURFACE-BASED CAPE OVER SOUTHWESTERN NORTH DAKOTA/EASTERN
MONTANA THIS AFTERNOON. HOWEVER...CONVECTION IS HAVING A DIFFICULT
TIME INITIATING AS MUCH COOLER BOUNDARY LAYER TEMPERATURES IN THE WAKE
OF AN MCV HAS GENERATED VERY WEAK LOW-LEVEL LAPSE RATES (0-3 KM
LAPSE RATES AROUND 6 C/KM OVER WESTERN NORTH DAKOTA PER SPC
ANALYSIS). RAPID DESTABILIZATION WILL NEED TO OCCUR TO GET
CONVECTION TO DEVELOP ALONG THE SURFACE TROUGH SETTING UP OVER
CENTRAL MONTANA LATER THIS AFTERNOON AND EARLY EVENING. FURTHER
COMPLICATING THE CONVECTIVE POTENTIAL IS A STRENGTHENING CAP OVER
WESTERN NORTH DAKOTA AHEAD OF THE DEEPENING LOW. MODELS CONTINUE TO
PROG CIN GREATER THAN 500 J/KG DEVELOPING OVER WESTERN NORTH DAKOTA
AFTER SUNSET AND CONTINUING OVERNIGHT. WITH THAT BEING SAID...THE
GREATEST DYNAMICS/SURFACE FORCING IS PROGGED TO SET UP OVER SOUTH
CENTRAL SASKATCHEWAN EARLY THIS EVENING. IF SAID CONVECTION
DEVELOPS...IT COULD DEVELOP ITS OWN COLD POOL AND ADVECT INTO THE
EXTREME NORTHWESTERN PORTIONS OF NORTH DAKOTA. AS A
RESULT...INCLUDED A SEVERE MENTION IN THE FORECAST FOR THE
NORTHWESTERN COUNTIES BETWEEN 00Z-06Z TONIGHT...CONSISTENT WITH
SPC`S DAY 1 OUTLOOK. THE MAIN THREATS WILL BE LARGE HAIL AND
DAMAGING WINDS. ISOLATED TORNADOES WILL ALSO BE POSSIBLE.
THIS ACTIVITY IS PROGGED TO WANE AFTER MIDNIGHT AS THE BOUNDARY
LAYER STABILIZES. DRY CONDITIONS ARE FORECAST TO CONTINUE AREAWIDE
THROUGH LATE THURSDAY MORNING.
BY THURSDAY AFTERNOON...A SURFACE TROUGH IS PROGGED TO STALL ACROSS
WESTERN NORTH DAKOTA. ENHANCED SURFACE MOISTURE CONVERGENCE ALONG
THE BOUNDARY COMBINED WITH MUCAPE VALUES BETWEEN 1500-2000
J/KG...AND 0-6KM SHEAR AROUND 35 KNOTS WILL LIKELY PRODUCE A LINE OF
THUNDERSTORMS EXTENDING FROM NORTH CENTRAL NORTH DAKOTA INTO
SOUTHWESTERN NORTH DAKOTA. THIS LINE COULD DEVELOP INTO A SQUALL
LINE WITH HEAVY RAINFALL AND DAMAGING WINDS BEING THE PRIMARY
THREATS. WILL HIGHLIGHT THIS POTENTIAL IN THE HWO FOR NOW.
.LONG TERM...(THURSDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 321 PM CDT WED MAY 28 2014
VERY ACTIVE WEATHER PATTERN THROUGH EARLY NEXT WEEK.
FORECAST HIGHLIGHTS IN THE LONG TERM PERIOD WILL BE CHANCES FOR
STRONG TO SEVERE THUNDERSTORMS AND VERY HEAVY RAINFALL THURSDAY
NIGHT THROUGH FRIDAY NIGHT...CONTINUED CHANCES FOR HEAVY RAIN OVER
THE WEEKEND AND INTO EARLY PORTIONS OF NEXT WEEK...ALONG WITH
COOLER TEMPERATURES OVER MUCH OF THE PERIOD.
SFC TROUGH MOVES SLOWLY EAST ACROSS WESTERN INTO CENTRAL NORTH
DAKOTA THURSDAY NIGHT...AND WILL BE THE FOCUS FOR DIURNALLY
DRIVEN THUNDERSTORMS...SOME POTENTIALLY SEVERE GIVEN THE
INSTABILITY AND FORCING ADVERTISED. MODELS STILL PORTRAY STRONG
MOISTURE TRANSPORT AHEAD OF THE SFC TROUGH POOLING ALONG THE
BOUNDARY...INCREASING THE POTENTIAL FOR HEAVY RAIN. PW VALUES ARE
PROJECTED TO NEAR THE 99TH PERCENTILE SO PLENTY OF MOISTURE TO
WORK WITH GENERATING WIDESPREAD 1-2 INCH RAINFALL. LOCALLY HIGHER
AMOUNTS WITH HEAVIER THUNDERSTORMS WILL BE VERY LIKELY. SFC TROUGH
SLOWLY MOVES EAST FRIDAY...BECOMING QUASI-STATIONARY OVER THE
SOUTH CENTRAL EAST INTO THE JAMES AND RED RIVER VALLEY REGIONS.
THUS ANOTHER ROUND OF STRONG TO SEVERE STORMS WITH HEAVY RAIN
LIKELY ALONG TO AHEAD OF THE SFC BOUNDARY. WILL MAINTAIN A DRY
FORECAST ACROSS THE NORTHWEST QUARTER OF ND FRIDAY WITH HIGH
PRESSURE AND A STABLE AIRMASS DEVELOPING SOUTH AND EAST FROM
CANADA IN THE WAKE OF THE TROUGH.
COOLER TEMPERATURES AND MORE STABLE CONDITIONS ARE STILL FORECAST
BY BOTH THE 12Z GFS/ECMWF SATURDAY THROUGH MONDAY WITH A COOL
NORTHEAST/EASTERLY FLOW DEVELOPING WITH HIGH PRESSURE OVER SOUTH
CENTRAL CANADA AND SURFACE LOW PRESSURE DEVELOPING FROM THE HIGH
PLAINS OF WYOMING EASTERLY INTO NEBRASKA/SOUTH DAKOTA. IDEAL
PLACEMENT FOR STRONG OVERRUNNING FLOW ACROSS NORTH
DAKOTA...SETTING US UP FOR A PROLONGED PERIOD OF MODERATE TO HEAVY
PRECIPITATION. WHILE THE MORE STABLE CONDITIONS RESULTS IN MINIMAL
CHANCES FOR SEVERE WEATHER...SOME GUIDANCE DOES TRY TO CREEP
MARGINAL INSTABILITY ACROSS MY FAR SOUTH SO WILL NOT COMPLETELY
RULE THIS OUT. HEAVY RAIN WILL BE THE MAIN IMPACT.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z THURSDAY NIGHT)
ISSUED AT 1220 AM CDT THU MAY 29 2014
BREEZY SOUTHEASTERLY WINDS WILL CONTINUE OVERNIGHT INTO THURSDAY
AS A STORM SYSTEM TRACKS FROM MONTANA NORTHEASTWARD TO CANADA.
SOME SHOWERS/THUNDERSTORMS ARE POSSIBLE ACROSS THE WEST /KISN/
OVER THE NEXT COUPLE OF HOURS. SO FAR...MOST LIGHTNING STRIKES
HAVE STAYED WEST OF KISN...SO WILL GO WITH SHOWERS FOR NOW AND
UPDATE TO ADD THUNDERSTORMS IF NECESSARY. A COLD FRONT SLOWLY
MOVES INTO WESTERN NORTH DAKOTA BY THURSDAY AFTERNOON WITH WINDS
SHIFTING TO THE WEST/NORTHWEST BEHIND IT. SHOWERS/THUNDERSTORMS
ARE EXPECTED TO DEVELOP ALONG THE FRONT...POSSIBLY AFFECTING
KMOT/KDIK LATE AFTERNOON. WILL KEEP THE MENTION OF PRECIPITATION
OUT OF KISN FOR NOW SINCE IT APPEARS MOST OF THE ACTIVITY MAY STAY
JUST EAST. DID INTRODUCE A PROB30 GROUP FOR KMOT/KDIK AS THE
CHANCES FOR CONVECTION INCREASE THURSDAY EVENING.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...CK
SHORT TERM...TM
LONG TERM...NH
AVIATION...CK
AREA FORECAST DISCUSSION
NWS TAMPA BAY RUSKIN FL
950 AM EDT THU MAY 29 2014
.UPDATE...
13Z WATER VAPOR AND H4 RAP ANALYSIS SHOWS A NORTHERN STREAM FLOW
ARRIVING OVER THE PACIFIC NORTHWEST AROUND THE BASE OF A SHARP
TROUGH AXIS BEFORE RIDGING BACK TO THE NORTH THROUGH SOUTH-CENTRAL
CANADA. THE FLOW THEN DROPS BACK TO THE SOUTHEAST THROUGH THE GREAT
LAKES AND THEN OFF THE NEW ENGLAND COAST. THE OTHER FEATURE OF NOTE
IS A CUT-OFF UPPER LOW STALLED NEAR THE BASE OF THE NORTHERN STREAM
RIDGE OVER THE SOUTHERN MS VALLEY. THIS FEATURE WILL NEVER REALLY
HAVE A SIGNIFICANT INFLUENCE ON OUR LOCAL WEATHER AS IT SPINS AND
PLACE AND SLOWLY FILLS DURING THE NEXT 24-48 HOURS.
29/12Z KTBW SOUNDING SHOWS A SEASONABLE PROFILE WITH A PW VALUES OF
JUST UNDER 1.5". MID-LEVEL TEMPS ARE A BIT ON THE COOL SIDE WITH A
MEASURED 500MB TEMP AROUND -11C. THIS IS ABOUT A DEGREE COOLER THAN
THE NAM/GFS FORECAST. A DEGREE DOES NOT SOUND LIKE MUCH...BUT CAN BE
ALL THE DIFFERENCE IN THE WORLD OF A RISING AIR PARCEL. EITHER
WAY...-11C IS ON THE COOL SIDE AND SHOULD HELP SUPPORT
AFTERNOON/EVENING STORM DEVELOPMENT...AT LEAST INITIALLY UNTIL
LATENT HEAT RELEASE FROM THE EARLY CONVECTION BEGINS TO CONTAMINATE
THE OVERALL COLUMN.
AT THE SURFACE...THE FL PENINSULA RESIDES ON THE WESTERN PERIPHERY
OF THE SUBTROPICAL RIDGE AXIS PROVIDING A GENERAL SOUTHEAST FLOW
PATTERN IN THE 1000-700MB LAYER. AS LONG AS THE COLUMN IS NOT TOO
DRY (WHICH IT IS NOT)...THEN THIS FLOW PATTERN TENDS TO BE WET ONE
IN TERMS OF STORMS COVERAGE THROUGH THE COURSE OF THE DAY.
CLIMATOLOGY UNDER THIS FLOW WOULD SUGGEST THAT INITIALLY THE BEST
STORM CHANCES WILL BE DOWN ACROSS THE SOUTHERN PART OF THE FORECAST
AREA...FT MYERS TO PUNTA GORDA...WITH THE FUTURE DEVELOPMENT
"RIPPLING" UP THE SEA-BREEZE TOWARD TAMPA BAY AND THE NATURE COAST
DURING THE LATER AFTERNOON AND ESPECIALLY EARLY EVENING HOURS.
LOCAL WRFARW ENSEMBLES ALSO AGREE WITH THIS SOLUTION...AND HAVE
UPDATED THE SPATIAL AND TEMPORAL EVOLUTION OF THE STORM PATTERN IN
THE FORECAST GRIDS TO MATCH THIS PHILOSOPHY.
LOCAL HIRES ARW SOLUTIONS ARE ALSO INDICATING MAXIMUM UPDRAFT
VELOCITIES BETWEEN 14-16 M/S. THIS VALUES ARE NOT OVERLY
IMPRESSIVE...BUT ENOUGH TO SUPPORT A FEW STRONGER STORMS. THESE
UPDRAFT VELOCITY VALUES OBVIOUSLY ARE NOT PERFECT...IN TERMS OF
EXACT VALUES OR LOCATIONS...BUT DO GIVE A GOOD REPRESENTATION OF
ATMOSPHERIC POTENTIAL.
THE SW FLOW PATTERN USUALLY HAS AN EARLIER ENDING TO THE SOUTH OF
TAMPA BAY AND A LATER ENDING FROM TAMPA BAY NORTHWARD. SO...KEEP
RAIN CHANCES IN FOR THE NORTHERN ZONES THROUGH 10-11 PM AND THEN
WIND EVERYTHING DOWN. THIS WILL GIVE US A GENERALLY QUIET OVERNIGHT
PERIOD. THE SYNOPTIC PATTERN AND STORMS SETUP LOOKS VERY SIMILAR FOR
FRIDAY...SO APPEARS THAT WE WILL DO IT ALL OVER AGAIN TOMORROW.
&&
.AVIATION...
VFR CONDITIONS PREVAIL ACROSS THE REGION THIS MORNING. A SCT-BKN
CUMULUS FIELDS WILL DEVELOP INTO THE EARLY AFTERNOON WHICH WILL GIVE
WAY TO A SCATTERING OF THUNDERSTORMS BY THE SECOND HALF OF THE
AFTERNOON. THREAT FOR STORMS SHOULD FIRST EXIST AROUND KFMY/KRSW
DURING THE MIDDLE AFTERNOON AND THEN SPREAD UP THE COAST TOWARD THE
TAMPA BAY TERMINALS BY THE EARLY EVENING HOURS. SHOWERS AND STORMS
SHIFT SHIFT NORTH AND WEST OF THE TERMINALS WITHIN A FEW HOURS OF
SUNSET ALLOWING FOR GENERAL VFR CONDITIONS TO PREVAIL FOR THE
MAJORITY OF THE OVERNIGHT.
&&
.MARINE...
HIGH PRESSURE IN THE ATLANTIC CONTINUES TO RIDGE OVER FLORIDA INTO
THE GULF WATERS PRODUCING SOUTHEAST WINDS IN THE 8 TO 12 KNOT RANGE.
WINDS ALONG THE COAST WILL VEER AROUND TO THE SOUTH SOUTHWEST EACH
AFTERNOON WITH THE ONSET OF THE SEA BREEZE. SEAS WILL REMAIN LESS
THAN 2 FEET THROUGH THE REMAINDER OF THE WEEK. THE MAIN MARINE
CONCERN WILL BE SCATTERED AFTERNOON AND EVENING THUNDERSTORMS
PRODUCING BRIEF GUSTY WINDS AND HIGHER SEAS.
&&
.PRELIMINARY POINT TEMPS/POPS...
TPA 88 72 89 74 / 60 50 60 40
FMY 91 71 90 72 / 60 30 60 40
GIF 91 71 90 71 / 60 30 60 30
SRQ 87 71 87 71 / 60 50 40 40
BKV 89 67 89 68 / 60 50 60 40
SPG 88 75 88 75 / 60 50 50 40
&&
.TBW WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
GULF WATERS...NONE.
&&
$$
UPDATE/AVIATION...MROCZKA
MARINE...WYNN/PERRINI
AREA FORECAST DISCUSSION
NWS MELBOURNE FL
913 AM EDT THU MAY 29 2014
.DISCUSSION...
A GREATER CHANCE FOR SHOWER AND THUNDERSTORM ACTIVITY WILL EXIST
ACROSS THE AREA TODAY AS RIDGE ALOFT CONTINUES TO BREAK DOWN AND
MOISTURE INCREASES IN A LOW LEVEL S/SE FLOW. 10Z SOUNDING FROM THE
CAPE ALREADY SHOWS A MORE MOIST COLUMN WITH PW VALUES UP TO 1.7
INCHES. ALSO LATEST SATELLITE IMAGERY SHOWS FEW CLOUDS OVER THE
REGION INITIALLY THIS MORNING WHICH WILL LEAD TO MORE THAN
SUFFICIENT INSTABILITY INTO THE AFTERNOON FOR SCATTERED
THUNDERSTORM DEVELOPMENT...ESPECIALLY OVER THE INTERIOR.
CONVECTION SHOULD START TO INCREASE ALONG THE TREASURE COAST WITH
ADDITIONAL SHOWERS AND STORMS FORMING FARTHER NORTH AND INLAND
THROUGH THE AFTERNOON.
GREATEST COVERAGE EXPECTED OVER THE INTERIOR...ESPECIALLY NEAR TO
WEST OF THE I-4 CORRIDOR LATER IN THE DAY WHERE SEA BREEZE
INTERACTIONS ARE MORE LIKELY. HAVE INCREASED RAIN CHANCES UP TO
30-40% ALONG THE TREASURE COAST BASED ON LATEST RADAR TRENDS AND
OUTPUT FROM THE HRRR AND LOCAL WRF. OTHERWISE RAIN CHANCES REMAIN
THE SAME...RANGING FROM 20 PERCENT ALONG THE BREVARD AND VOLUSIA
COAST UP TO 50-60 PERCENT OVER THE INTERIOR. A FEW STRONG STORMS
WILL ONCE AGAIN BE POSSIBLE WITH STRONG WIND GUSTS...SMALL
HAIL...FREQUENT LIGHTNING AND LOCALLY HEAVY RAINFALL THE MAIN
THREATS.
INCREASING CLOUD COVER EXPECTED INTO THE AFTERNOON AS CONVECTION
CONTINUES TO DEVELOP. THIS MAY LEAD TO MAX TEMPS A SLIGHTLY LOWER
OVER THE INTERIOR TODAY. CURRENTLY HAVE HIGHS FORECAST FOR THE
UPPER 80S/AROUND 90 INLAND WITH MID-UPPER 80S ALONG THE COAST.
&&
.AVIATION...MAINLY VFR THROUGH THIS MORNING THEN TEMPO IFR/MVFR
CONDS IN INCREASING SHOWER AND THUNDERSTORM ACTIVITY ALONG AND
INLAND OF THE EAST COAST SEA BREEZE THROUGH THE AFTERNOON. HIGHEST
COVERAGE EXPECTED OVER THE INTERIOR...ESPECIALLY NEAR TO WEST OF
KMCO LATER IN THE DAY WHERE SEA BREEZE INTERACTIONS WILL BE MOST
LIKELY. CONVECTION WILL WIND DOWN OVER THE INTERIOR THIS EVENING
WITH VFR CONDITIONS EXPECTED OVERNIGHT.
&&
.MARINE...
TODAY-TONIGHT...SURFACE RIDGE AXIS REMAINS JUST NORTH OF THE AREA.
EAST TO SOUTHEAST WINDS 5 TO 10 KNOTS EARLY THEN INCREASING TO 10
TO 15 KNOTS IN THE AFTERNOON DUE TO SEA BREEZE CONTRIBUTIONS.
WINDS VEER TO THE SOUTH TO SOUTHEAST TONIGHT AND AVERAGE 10 TO 15
KNOTS. SEAS RANGING FROM 1-2 FEET.
&&
.MLB WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
AM...NONE.
&&
$$
WEITLICH/KELLY
Area Forecast Discussion
National Weather Service Lincoln IL
1036 AM CDT Thu May 29 2014
.DISCUSSION...
ISSUED 1036 AM CDT Thu May 29 2014
Back-door cool front has slipped south to just north of the I-70
corridor. True push of cool/dry air lags well north of the front,
though northeast flow north of the boundary has brought slightly
cooler and less humid air into the far northern CWA with dewpoints
in the low 60s, while upper 60s dewpoints remain over the central
and south. Aloft, water vapor imagery indicates a cutoff low
spinning through the lower MS valley with the northern fringes of
this feature bringing clouds into the southern CWA and lift
producing showers in far southern IL/IN. A separate weak shortwave
was noted in NW IL and is forecast to get absorbed into the
circulation of the upper low as is shifts SE today. 12Z ILX
sounding shows little airmass change from yesterday even as the
front has shifted south. Given afternoon CAPEs near 2000 J/kg and
light wind fields aloft, expect isolated to scattered thunderstorm
development as convective temperatures are reached. Hi-res models
show this possible for much of the CWA except the far north where
somewhat drier air should keep areas north of Peoria and Galesburg
dry. For the bulk of the CWA, slow moving iso/sct storms will
produce brief heavy rain rates. Given high instability and weak
shear with a boundary in the area, isolated land spouts will again
be a concern. Non-supercell tor parameters off RAP and NAM
suggest the central/southern CWA will again be at risk during
early to mid afternoon, especially near the main synoptic boundary or
mesoscale boundary interactions. Raised max temps a degree or two
with highs in the lower 80s.
25
&&
.AVIATION...
ISSUED 600 AM CDT Thu May 29 2014
Areas of MVFR cigs/vsbys possible thru 14z...then VFR conditions
expected into this evening. The front that moved thru our area
last evening has shifted well south of the TAF sites. As a result,
winds have become east to northeast over the entire area and are
expected to remain that way today. A band of MVFR cigs with some
local IFR cigs noted on the latest satellite data just to our
north and east, tracking west and northwest. The bulk of the lower
cigs will remain just to our north over the next few hours but
over the past few hours have noted an increase in stratus on the
southwest flank of the cloud bank so may have to include a period
of IFR cigs at KBMI in the 12z-15z time frame.
Once we burn of the fog/hz and cig restrictions this morning,
forecast soundings suggest a rapid increase in cumulus after 15z
with scattered to broken cigs at or above 5000 feet by late morning
into the afternoon hours. Will continue with VCTS at all TAF sites
but it appears the better coverage of storms will be south of I74
this afternoon. Any convection that does develop this afternoon
should dissipate by early this evening but with the residual low
level moisture in place, we could see some MVFR vsbys develop again
in fog aftr 08z. East to northeast winds will prevail today with
speeds of 8 to 13 kts and the trend more from an east direction
tonight at less than 10 kts.
Smith
&&
.PREV DISCUSSION...
ISSUED 250 AM CDT Thu May 29 2014
Weak frontal boundary centered just north of the I-70 corridor
early this morning. High pressure over the Great Lakes is
providing a northeast flow behind the front, which has dropped dew
points into the 50s from Galesburg to Bloomington northward, while
mid to upper 60s still prevail elsewhere. Still a fair amount of
cloud cover over the forecast area, some streaming north from the
ever-present upper low, now centered in south central Arkansas.
There were a few showers recently near the boundary which drifted
northwest due to that low, although these have now faded out.
Rain chances continue to be the primary forecast concern, with
next week`s chances a bit more challenging due to more model
disagreement.
SHORT TERM...Today through Saturday:
The frontal boundary should be quasi-stationary between the I-72
and I-70 corridors today, and will be the focus for the next round
of scattered showers and storms beginning around noon. Have had
some heavier pockets of rain recently, and with precipitable water
values around 1.5 to 1.6 inches, today shouldn`t be any different.
Severe weather threat remains minimal due to low shear values, but
cannot rule out some isolated funnels or land spouts similar to
yesterday, with the boundary overhead. Non-supercell tornado
parameter from the RAP model focuses on a couple areas, one along
the I-74 corridor just north of the main precipitation area, and
the other along I-72 near the boundary. Any such activity would be
most likely between noon and 4 pm.
The boundary will be pushed southward again tonight as an upper
high slides moves into the upper Mississippi Valley. As it will
not make it terribly far, the convection on Friday and Saturday will
be close by, but mostly out of our forecast area. Have maintained
some 20% PoP`s along the southern CWA border Friday afternoon, but
kept Saturday dry for now.
LONG TERM...Sunday through Wednesday:
Upper ridging breaks down during the weekend with more of a
southwest flow across the nation early next week, and the northern
jet stream along the Canadian border. Right now the ECMWF is the
odd model out in developing an upper low over the upper
Mississippi Valley which slowly drifts eastward through the Great
Lakes during the week, while the GFS, GEM and GFS ensembles have
more of periodic shortwave interaction between the two upper flows.
Sunday into early Monday are in most agreement with rain chances,
but trends widen after that. The ECMWF and the GEM to an extent
have the surface cyclone somewhat in agreement into Tuesday with
the cold front coming through, which would support the rain
chances continuing. Toward mid week, there is much more
uncertainty as the GFS never actually brings the front through and
holds it up near I-80, thus lingering rain chances, while the
ECMWF is dry. Have kept some PoP`s in for Wednesday for now, but
scaled them back from the initial blended guidance.
Geelhart
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
633 AM CDT THU MAY 29 2014
.DISCUSSION...
346 AM CDT
FORECAST CONCERNS THIS MORNING FOCUS ON DRIER NORTHEAST LOW LEVEL
WINDS TODAY...WITH DECREASING CLOUDINESS AND THREAT OF AFTERNOON
THUNDERSTORMS SHIFTING DOWNSTATE ALONG/SOUTH OF WFO LOT/ILX BORDER.
DRY AND MILD CONDITIONS ANTICIPATED OVER THE NEXT FEW DAYS WITH A
WARMING TREND INTO THE WEEKEND...AND A GRADUAL DECREASE IN LAKE
COOLING. A PERIOD OF ACTIVE WEATHER WITH HEAVY RAINFALL AND
INCREASING SEVERE THUNDERSTORM POTENTIAL APPEARS TO BE SHAPING UP
FOR DAYS 4-7 (SUNDAY-NEXT WEDNESDAY)...AS A COLD FRONT SAGS INTO
WARM/HUMID AIR MASS WHICH TAKES UP RESIDENCE ACROSS THE AREA.
WEAK SURFACE LOW PRESSURE CONTINUES TO SETTLE SOUTHWARD ACROSS
EASTERN MISSOURI THIS MORNING...WITH A NEARLY STATIONARY COLD FRONT
STRETCHING WEST-EAST ACROSS SOUTH CENTRAL IL/IN. THIS BOUNDARY WILL
CONTINUE TO BE THE FOCUS FOR DIURNAL SHOWER/THUNDERSTORM DEVELOPMENT
THIS AFTERNOON...AS WEAKENING SHEARED MID-LEVEL VORT MAXIMA
CONTINUES TO DRIFT SOUTH WHILE GETTING PULLED INTO CIRCULATION
AROUND CLOSED UPPER LOW OVER THE LOWER MISSISSIPPI VALLEY. VARIOUS
HIGH-RES CONVECTIVE-ALLOWING GUIDANCE DEPICTS AFTERNOON CONVECTION
DEVELOPING GENERALLY ALONG/SOUTH OF OUR SOUTHERN CWA BORDER...THUS
HAVE MAINTAINED SOME SLIGHT CHANCE POPS SOUTH OF ABOUT A FAIRBURY TO
WATSEKA TO FOWLER LINE. FARTHER NORTH...NORTHEAST LOW LEVEL WINDS
CONTINUE TO BRING DRIER AND MORE STABLE AIR INTO THE AREA FROM
ACROSS THE LAKES. PATCHY LOW CLOUD COVER OVER PARTS OF THE AREA
SHOULD CLEAR OUT LATER THIS MORNING...WITH MODEL FORECAST SOUNDINGS
INDICATING WARMING AND DRYING FROM ABOVE AS SUBSIDENCE DEVELOPS WITH
UPPER RIDGE BUILDING INTO THE UPPER MIDWEST. THIS UPPER RIDGE
CONTINUES TO BUILD AND SLOWLY DRIFT SOUTHEAST ACROSS THE REGION INTO
SATURDAY...PRODUCING DRY CONDITIONS WITH A STEADY MODERATION IN
TEMPERATURES. SURFACE HIGH PRESSURE WILL REMAIN TO OUR NORTHEAST AND
EAST DURING THE PERIOD...GRADUALLY WEAKENING AND PULLING OFF TO THE
EAST AND ALLOWING NORTHEAST SURFACE WINDS TO GRADUALLY VEER
SOUTHEAST AND DECREASING THE AMOUNT OF LAKE COOLING. WITH A GOOD
AMOUNT OF SUNSHINE EXPECTED TODAY...FRIDAY AND SATURDAY...HAVE
GENERALLY UTILIZED WARMER GUIDANCE FOR HIGH TEMPS...WITH UPPER 70S
AND LOWER 80S EXPECTED TODAY WELL AWAY FROM THE LAKE WARMING TO THE
LOW-MID 80S BY SATURDAY. AS FETCH ACROSS THE LAKE DECREASES WITH
VEERING LOW LEVEL WINDS...SHORE AREAS SHOULD ALSO MODERATE FROM THE
LOW-MID 60S TODAY TO THE LOW-MID 70S BY SATURDAY. DRY AIR WILL
SUPPORT COOL OVERNIGHT TEMPS PARTICULARLY ACROSS NORTHEAST IL...WITH
A FEW UPPER 40S POSSIBLE TONIGHT NEAR THE LAKE.
ON SATURDAY...THE UPPER RIDGE AXIS WILL SHIFT SOUTHEAST OF THE AREA
AS A STRONG UPPER JET MAX SPREADS ACROSS ONTARIO AND THE FAR UPPER
MIDWEST. MEDIUM RANGE MODEL SOLUTIONS ARE IN GOOD AGREEMENT IN
DEPICTING A SHORT WAVE LIFTING FROM THE PLAINS TOWARD THE UPPER
MISSISSIPPI VALLEY SATURDAY AFTERNOON/NIGHT...HELPING INDUCE SURFACE
PRESSURE FALLS ACROSS THE UPPER MISSISSIPPI VALLEY AND VEERING LOW
LEVEL WINDS MORE SOUTHERLY. WARM/MOIST ADVECTION IN RETURN FLOW WILL
BRING WARM AND HUMID CONDITIONS BACK TO THE FORECAST AREA BY
SUNDAY...WITH THE POTENTIAL FOR A FEW ELEVATED THUNDERSTORMS ACROSS
NORTHWEST IL TOWARD SUNDAY MORNING ALONG EASTERN PERIPHERY OF BROAD
SOUTHWESTERLY LOW LEVEL JET AND THE SUBTLE WARM FRONT. POTENTIAL FOR
THUNDERSTORMS INCREASES AS AREA BECOMES FIRMLY ENTRENCHED IN THE
WARM SECTOR SUNDAY AND SUNDAY NIGHT...WITH TEMPS MID-UPPER 80S AND
DEW POINT TEMPS 65-70 PROGGED.
GUIDANCE DIFFERS WITH DETAILS OF SHORT WAVES MOVING THROUGH
SOUTHWEST FLOW ALOFT INTO EARLY NEXT WEEK...THOUGH THE POTENTIAL
EXISTS FOR SEVERAL ROUNDS OF THUNDERSTORMS TO AFFECT THE REGION INTO
AT LEAST TUESDAY AS COLD FRONT SLOWLY MOVES SOUTH INTO A VERY WARM
AND MOIST AIR MASS. WEST-SOUTHWEST TO EAST-NORTHEAST ORIENTATION OF
BOUNDARY COMBINED WITH HIGH PRECIPITABLE WATER VALUES (1.5-2.0
INCHES PER GFS SOUNDINGS) WILL LIKELY SUPPORT A HEAVY RAINFALL
THREAT...AND INCREASING DEEP LAYER BULK SHEAR ESPECIALLY MON-WED
ALSO SUGGESTS SEVERE MCS POTENTIAL. FOR NOW HAVE MAINTAINED RATHER
BROAD-BRUSHED CHANCE POPS FROM SUNDAY ONWARD...THOUGH DETAILS SUCH
AS THE LOCATION OF THE FRONTAL BOUNDARY (LIKELY MODULATED BY
CONVECTIVE OUTFLOWS)...AS WELL AS INDIVIDUAL LOW-AMPLITUDE WAVES
WILL ULTIMATELY DRIVE CONVECTIVE TRENDS AND TIMING DURING THIS
PERIOD.
RATZER
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 12Z...
* MVFR/IFR CIGS SCATTERING OUT MID TO LATE MORNING.
BMD
//DISCUSSION...UPDATED 12Z...
IFR/MVFR STRATUS HAS OVERSPREAD THE TERMINALS THIS MORNING AND IS
EXPECTED TO PERSIST FOR A FEW HOURS BEFORE SCATTERING OUT MID TO
LATE THIS MORNING AND RETURNING TO VFR. HIGH PRESSURE OVER THE GREAT
LAKES WILL THEN PROVIDE FAIR WEATHER WITH MODEST NORTHEAST WIND
THROUGH THE REMAINDER OF THE DAY. WINDS WILL GRADUALLY PICK UP
THROUGH THE MORNING...TOPPING OUT A LITTLE OVER 10 KTS BY LATE
MORNING THROUGH THE AFTERNOON HOURS AND EARLY EVENING HOURS.
ANOTHER VFR DAY IS ON TAP TOMORROW WITH WINDS OUT OF THE EAST.
BMD
//ORD AND MDW CONFIDENCE...UPDATED 12Z...
* MEDIUM CONFIDENCE IN DURATION OF LOWER CIGS.
* HIGH CONFIDENCE IN REMAINING FORECAST ELEMENTS....
BMD
//OUTLOOK FOR ORD/MDW FOR 00Z SATURDAY-12Z THURSDAY...UPDATED 12Z...
FRIDAY NIGHT THROUGH SATURDAY...VFR.
SUNDAY THROUGH WEDNESDAY...PERIODIC CHANCES FOR THUNDERSTORMS.
PRIMARILY VFR.
BMD
&&
.MARINE...
246 AM CDT
HIGH PRESSURE EXTENDS FROM HUDSON BAY INTO THE CENTRAL GREAT LAKES
REGION WHERE IT WILL SLOWLY MIGRATE TO THE EASTERN LAKES BY
SATURDAY. IN THE MEANTIME...MODEST NORTHEAST TO EAST WINDS WILL
PREVAIL ACROSS LAKE MICHIGAN. WINDS ARE EXPECTED TO BE STRONGEST ON
THE SOUTH END OF THE LAKE WHERE IT MAY PEAK AROUND 15 TO 20 KT THIS
AFTERNOON. A WARM FRONT WILL LIFT ACROSS LAKE MICHIGAN THIS WEEKEND
WITH WINDS VEERING AROUND TO THE SOUTH BY SUNDAY. SOUTH TO SOUTHWEST
WINDS ARE THEN EXPECTED TO PERSIST THROUGH AROUND MIDWEEK WITH
ANOTHER COLD FRONT DROPS ACROSS THE LAKE.
BMD
&&
.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:
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WWW.TWITTER.COM/NWSCHICAGO
WWW.YOUTUBE.COM/NWSCHICAGO
Area Forecast Discussion
National Weather Service Lincoln IL
602 AM CDT Thu May 29 2014
.DISCUSSION...
ISSUED 250 AM CDT Thu May 29 2014
Weak frontal boundary centered just north of the I-70 corridor
early this morning. High pressure over the Great Lakes is
providing a northeast flow behind the front, which has dropped dew
points into the 50s from Galesburg to Bloomington northward, while
mid to upper 60s still prevail elsewhere. Still a fair amount of
cloud cover over the forecast area, some streaming north from the
ever-present upper low, now centered in south central Arkansas.
There were a few showers recently near the boundary which drifted
northwest due to that low, although these have now faded out.
Rain chances continue to be the primary forecast concern, with
next week`s chances a bit more challenging due to more model
disagreement.
SHORT TERM...Today through Saturday:
The frontal boundary should be quasi-stationary between the I-72
and I-70 corridors today, and will be the focus for the next round
of scattered showers and storms beginning around noon. Have had
some heavier pockets of rain recently, and with precipitable water
values around 1.5 to 1.6 inches, today shouldn`t be any different.
Severe weather threat remains minimal due to low shear values, but
cannot rule out some isolated funnels or land spouts similar to
yesterday, with the boundary overhead. Non-supercell tornado
parameter from the RAP model focuses on a couple areas, one along
the I-74 corridor just north of the main precipitation area, and
the other along I-72 near the boundary. Any such activity would be
most likely between noon and 4 pm.
The boundary will be pushed southward again tonight as an upper
high slides moves into the upper Mississippi Valley. As it will
not make it terribly far, the convection on Friday and Saturday will
be close by, but mostly out of our forecast area. Have maintained
some 20% PoP`s along the southern CWA border Friday afternoon, but
kept Saturday dry for now.
LONG TERM...Sunday through Wednesday:
Upper ridging breaks down during the weekend with more of a
southwest flow across the nation early next week, and the northern
jet stream along the Canadian border. Right now the ECMWF is the
odd model out in developing an upper low over the upper
Mississippi Valley which slowly drifts eastward through the Great
Lakes during the week, while the GFS, GEM and GFS ensembles have
more of periodic shortwave interaction between the two upper flows.
Sunday into early Monday are in most agreement with rain chances,
but trends widen after that. The ECMWF and the GEM to an extent
have the surface cyclone somewhat in agreement into Tuesday with
the cold front coming through, which would support the rain
chances continuing. Toward mid week, there is much more
uncertainty as the GFS never actually brings the front through and
holds it up near I-80, thus lingering rain chances, while the
ECMWF is dry. Have kept some PoP`s in for Wednesday for now, but
scaled them back from the initial blended guidance.
Geelhart
&&
.AVIATION...
ISSUED 600 AM CDT Thu May 29 2014
Areas of MVFR cigs/vsbys possible thru 14z...then VFR conditions
expected into this evening. The front that moved thru our area
last evening has shifted well south of the TAF sites. As a result,
winds have become east to northeast over the entire area and are
expected to remain that way today. A band of MVFR cigs with some
local IFR cigs noted on the latest satellite data just to our
north and east, tracking west and northwest. The bulk of the lower
cigs will remain just to our north over the next few hours but
over the past few hours have noted an increase in stratus on the
southwest flank of the cloud bank so may have to include a period
of IFR cigs at KBMI in the 12z-15z time frame.
Once we burn of the fog/hz and cig restrictions this morning,
forecast soundings suggest a rapid increase in cumulus after 15z
with scattered to broken cigs at or above 5000 feet by late morning
into the afternoon hours. Will continue with VCTS at all TAF sites
but it appears the better coverage of storms will be south of I74
this afternoon. Any convection that does develop this afternoon
should dissipate by early this evening but with the residual low
level moisture in place, we could see some MVFR vsbys develop again
in fog aftr 08z. East to northeast winds will prevail today with
speeds of 8 to 13 kts and the trend more from an east direction
tonight at less than 10 kts.
Smith
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS INDIANAPOLIS IN
1028 AM EDT THU MAY 29 2014
.UPDATE...
AVIATION SECTION UPDATED.
&&
.SYNOPSIS...
ISSUED AT 317 AM EDT THU MAY 29 2014
SCATTERED THUNDERSTORMS ARE EXPECTED ONCE AGAIN TODAY AS A SLOW
MOVING FRONT DROPS SOUTH. THE FRONT WILL EVENTUALLY SLIP SOUTH OF
THE OHIO RIVER TONIGHT AS STRONG HIGH PRESSURE BUILDS IN FROM THE
NORTH. WARM DRY WEATHER IS ANTICIPATED INTO SUNDAY AS THE HIGH
CENTERS OVER THE REGION. A MORE UNSETTLED PATTERN RETURNS FOR THE
FIRST HALF OF NEXT WEEK WITH CHANCES FOR THUNDERSTORMS.
&&
.NEAR TERM /REST OF TODAY/...
ISSUED AT 937 AM EDT THU MAY 29 2014
1330Z UPDATE...FEW CHANGES TO GOING FORECAST...MAINLY TO ACCOUNT
FOR MUCH DRIER TREND EARLY THIS MORNING AND TO DROP FOG FROM
FORECAST. OTHERWISE FORECAST LOOKS TO BE IN PRETTY GOOD SHAPE.
PREVIOUS DISCUSSION FOLLOWS.
ANOTHER STICKY MORNING WITH PLENTY OF CLOUD DEBRIS ACROSS THE
REGION. CONVECTION HAS LARGELY DIMINISHED WITH THE EXCEPTION OF A
SMALL PERSISTENT CELL NEAR KMIE WHICH WAS FINALLY WEAKENING. TEMPS
WERE GENERALLY IN THE 60S AS OF 07Z WITH PATCHY FOG DEVELOPING IN
AREAS THAT RECEIVED RAIN ON WEDNESDAY.
THE CATALYSTS FOR CONVECTIVE DEVELOPMENT WILL BE THE SAME AS THEY
HAVE BEEN THE LAST FEW DAYS...MODEST INSTABILITY AND THE PRESENCE OF
THE SLOWLY SOUTHWARD MOVING FRONTAL BOUNDARY. A REMNANT OUTFLOW
BOUNDARY THAT APPEARS TO BE LOCATED FROM NEAR KHUF SOUTHEAST TO KBMG
AND SEYMOUR IS THE WILDCARD TODAY...AS IT WILL LIKELY BE A FOCAL
POINT FOR STORMS TO FIRE ONCE CONVECTIVE TEMPS ARE MET BY EARLY
AFTERNOON. SHORT RANGE MODEL GUIDANCE ALSO HINTING AT A WEAK AXIS OF
MID LEVEL FORCING ALIGNING NORTHWEST-SOUTHEAST ACROSS THE CENTER OF
THE FORECAST AREA THIS AFTERNOON BEFORE GRADUALLY SHIFTING SOUTH.
WHILE THE GREATEST CONVECTIVE COVERAGE WILL BE FOUND PRIMARILY SOUTH
OF I-70...THE PRESENCE OF THE WEAK FORCING ALOFT SUPPORTS SCATTERED
CONVECTION ALL THE WAY NORTH TO A CRAWFORDSVILLE-NOBLESVILLE-
ANDERSON LINE. HRRR AND WRF REFLECTIVITY PROGS FOR THIS AFTERNOON
BOTH SUPPORT THIS IDEA IN THE 18-21Z TIME PERIOD BEFORE SHIFTING
STORMS SOUTH AS DRIER AIR ATTEMPTS TO ADVECT IN FROM THE NORTHEAST.
WILL CARRY CHANCE POPS FOR ALL BUT THE FAR NORTHERN COUNTIES
TODAY...WITH HIGHEST POPS DURING THE AFTERNOON AND ACROSS THE
SOUTHERN HALF OF THE FORECAST AREA. LARGELY DISORGANIZED
MULTICELLULAR CONVECTION ONCE AGAIN FAVORED IN THE ABSENCE OF BL
SHEAR...WITH TORRENTIAL RAINFALL AND LOCALIZED FLOODING THE PRIMARY
IMPACT AS STORM MOTIONS WILL BE GENERALLY 10KTS OR LESS.
TEMPS...DEPENDING ON HOW QUICKLY STORMS GET GOING...POTENTIAL EXISTS
FOR TEMPS TO OVERACHIEVE A BIT TODAY. WENT AT OR JUST ABOVE WARMER
MAVMOS.
&&
.SHORT TERM /TONIGHT THROUGH SATURDAY NIGHT/...
ISSUED AT 317 AM EDT THU MAY 29 2014
FORECAST CHALLENGES ARE FEW THROUGH THE PERIOD...AS HIGH PRESSURE
ASSERTS CONTROL OVER THE REGION FOR MUCH OF THE SHORT TERM.
ANTICIPATE LINGERING CONVECTION FOCUSED OVER SOUTHERN COUNTIES NEAR
THE REMNANT FRONTAL BOUNDARY THIS EVENING...WITH STORMS DIMINISHING
BY MIDNIGHT AS THE AIRMASS STABILIZES AND PROGRESSIVELY DRIER AIR
SPREADS IN WITH THE HIGH PRESSURE TO THE NORTH. DEEPER MOISTURE AXIS
WILL REMAIN JUST TO THE SOUTHWEST OF THE FORECAST AREA ON
FRIDAY...CLOSE ENOUGH THAT AN ISOLATED STORM CANNOT BE ENTIRELY
RULED OUT OVER THE EXTREME SOUTHWEST FORECAST AREA. HOWEVER WITH
COVERAGE SPARSE AT BEST WILL MAINTAIN A DRY FORECAST.
OVER THE REMAINDER OF THE FORECAST AREA...THE SURFACE HIGH WILL TAKE
ROOT WITH STRONG RIDGING ALOFT ESTABLISHING AS WELL. MODEL SOUNDINGS
AND RH PROGS INDICATE DEEP SUBSIDENCE ACCOMPANYING THE HIGH WITH
ABUNDANT SUNSHINE ANTICIPATED FRIDAY AND SATURDAY AS A PREDOMINANT
DRY E/NE FLOW CONTINUES. ALL IN ALL...SHAPING UP TO BE A GREAT
WEEKEND FOR CENTRAL INDIANA.
TEMPS...DESPITE SLIGHTLY COOLER 850MB TEMPS FRIDAY AND SATURDAY...
PRESENCE OF THE UPPER RIDGE AND ABUNDANT SUNSHINE WILL COMPENSATE
WITH HIGHS INTO THE 80S FRIDAY AND SATURDAY. LEANED TOWARDS WARMER
MAVMOS GUIDANCE BOTH DAYS. EXPECT LOWS INTO THE 50S IN SOME OF OUR
NORMAL COOL SPOTS BOTH TONIGHT AND FRIDAY NIGHT...ESPECIALLY NORTH
AND EAST OF THE INDY METRO. WENT ABOVE GUIDANCE AT INDY FOR LOWS
TONIGHT AND FRIDAY NIGHT WITH A LIGHT E/NE FLOW.
&&
.LONG TERM /SUNDAY THROUGH WEDNESDAY/...
ISSUED AT 317 AM EDT THU MAY 29 2014
AN UPPER RIDGE OVER CENTRAL INDIANA WILL MOVE EAST AND WIND UP OFF
THE EAST COAST BY THE END OF THE LONG TERM. AN UPPER TROUGH OVER THE
WESTERN U.S. WILL ALLOW WEAK SHORTWAVES TO MOVE THROUGH THE FLOW AND
BRING THUNDERSTORM CHANCES TO CENTRAL INDIANA THROUGHOUT THE LONG
TERM. WITH THE SOUTHWESTERLY FLOW OVER THE AREA CONDITIONS WILL
REMAIN WARM AND HUMID AS THE GULF REMAINS OPEN. NO STRONG FEATURES
TO FOCUS ON SO STUCK WITH INITIALIZATION CHANCE POPS FROM SUNDAY
NIGHT ON. FOR SUNDAY MORNING THE UPPER RIDGE WILL JUST BE STARTING
TO MOVE EAST AND THUS THINK PRECIPITATION WILL HAVE A HARD TIME
MOVING EAST INTO THE AREA UNDER UPPER SUBSIDENCE. THUS WENT DRY FOR
SUNDAY MORNING AND BROUGHT IN LOW CHANCE POPS IN THE WEST IN THE
AFTERNOON.
&&
.AVIATION /DISCUSSION FOR THE 291200Z IND TAF UPDATE/...
ONGOING TAF IS GOOD SHAPE AND ONLY MINOR CHANGES HAVE BEEN MADE.
CONVECTIVE TEMPS IN THE UPPER 70S SHOULD BE EASILY REACHED LATE
THIS MORNING AND CU DEVELOPMENT SHOULD BEGIN. HRRR CONTINUES TO
SUGGEST SCT SHRA/TSRA DEVELOPMENT THIS AFTERNOON IN THE I-70
CORRIDOR...THUS WILL CONTINUE THE USE OF VCTS FOR NOW.
PREVIOUS DISCUSSION BELOW
/DISCUSSION FOR 291200Z TAF ISSUANCE/...
ISSUED AT 652 AM EDT THU MAY 29 2014
COULD HAVE AN HOUR OR SO OF MVFR FOG AT THE OUTLYING SITES. AT KLAF
SHOULD SEE IFR CEILINGS STICK AROUND FOR A COUPLE HOURS BEFORE IT
MIXES UP AND SCATTERS OUT. AFTER THAT WILL SEE SOME CHANCES FOR
THUNDERSTORMS DURING THE AFTERNOON AND EVENING AT ALL BUT KLAF WITH
THE COLD FRONT SLOWLY SINKING SOUTH THROUGH CENTRAL/SOUTHERN
INDIANA. HRRR AND RAP SHOW QPF DEVELOPING ALONG/SOUTH OF I-70
STARTING AFTER 18Z OR SO AND LASTING THROUGH AROUND 1Z AND INCLUDED
VCTS DURING THIS TIME. COULD SEE MVFR VISIBILITIES AND POSSIBLY
CEILINGS DEVELOP AGAIN DURING THE OVERNIGHT HOURS. WINDS LESS THAN
10 KTS THROUGH THE PERIOD.
&&
.IND WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...RYAN
NEAR TERM...SMF/RYAN
SHORT TERM...RYAN
LONG TERM....CP
AVIATION...CP/JP
VISIT US AT HTTP://WWW.WEATHER.GOV/IND
FOLLOW US ON TWITTER AND YOUTUBE AT:
WWW.TWITTER.COM/NWSINDIANAPOLIS
WWW.YOUTUBE.COM/NWSINDIANAPOLIS
AREA FORECAST DISCUSSION
NWS INDIANAPOLIS IN
940 AM EDT THU MAY 29 2014
.UPDATE...
THE NEAR TERM SECTION HAS BEEN UPDATED BELOW.
&&
.SYNOPSIS...
ISSUED AT 317 AM EDT THU MAY 29 2014
SCATTERED THUNDERSTORMS ARE EXPECTED ONCE AGAIN TODAY AS A SLOW
MOVING FRONT DROPS SOUTH. THE FRONT WILL EVENTUALLY SLIP SOUTH OF
THE OHIO RIVER TONIGHT AS STRONG HIGH PRESSURE BUILDS IN FROM THE
NORTH. WARM DRY WEATHER IS ANTICIPATED INTO SUNDAY AS THE HIGH
CENTERS OVER THE REGION. A MORE UNSETTLED PATTERN RETURNS FOR THE
FIRST HALF OF NEXT WEEK WITH CHANCES FOR THUNDERSTORMS.
&&
.NEAR TERM /REST OF TODAY/...
ISSUED AT 937 AM EDT THU MAY 29 2014
1330Z UPDATE...FEW CHANGES TO GOING FORECAST...MAINLY TO ACCOUNT
FOR MUCH DRIER TREND EARLY THIS MORNING AND TO DROP FOG FROM
FORECAST. OTHERWISE FORECAST LOOKS TO BE IN PRETTY GOOD SHAPE.
PREVIOUS DISCUSSION FOLLOWS.
ANOTHER STICKY MORNING WITH PLENTY OF CLOUD DEBRIS ACROSS THE
REGION. CONVECTION HAS LARGELY DIMINISHED WITH THE EXCEPTION OF A
SMALL PERSISTENT CELL NEAR KMIE WHICH WAS FINALLY WEAKENING. TEMPS
WERE GENERALLY IN THE 60S AS OF 07Z WITH PATCHY FOG DEVELOPING IN
AREAS THAT RECEIVED RAIN ON WEDNESDAY.
THE CATALYSTS FOR CONVECTIVE DEVELOPMENT WILL BE THE SAME AS THEY
HAVE BEEN THE LAST FEW DAYS...MODEST INSTABILITY AND THE PRESENCE OF
THE SLOWLY SOUTHWARD MOVING FRONTAL BOUNDARY. A REMNANT OUTFLOW
BOUNDARY THAT APPEARS TO BE LOCATED FROM NEAR KHUF SOUTHEAST TO KBMG
AND SEYMOUR IS THE WILDCARD TODAY...AS IT WILL LIKELY BE A FOCAL
POINT FOR STORMS TO FIRE ONCE CONVECTIVE TEMPS ARE MET BY EARLY
AFTERNOON. SHORT RANGE MODEL GUIDANCE ALSO HINTING AT A WEAK AXIS OF
MID LEVEL FORCING ALIGNING NORTHWEST-SOUTHEAST ACROSS THE CENTER OF
THE FORECAST AREA THIS AFTERNOON BEFORE GRADUALLY SHIFTING SOUTH.
WHILE THE GREATEST CONVECTIVE COVERAGE WILL BE FOUND PRIMARILY SOUTH
OF I-70...THE PRESENCE OF THE WEAK FORCING ALOFT SUPPORTS SCATTERED
CONVECTION ALL THE WAY NORTH TO A CRAWFORDSVILLE-NOBLESVILLE-
ANDERSON LINE. HRRR AND WRF REFLECTIVITY PROGS FOR THIS AFTERNOON
BOTH SUPPORT THIS IDEA IN THE 18-21Z TIME PERIOD BEFORE SHIFTING
STORMS SOUTH AS DRIER AIR ATTEMPTS TO ADVECT IN FROM THE NORTHEAST.
WILL CARRY CHANCE POPS FOR ALL BUT THE FAR NORTHERN COUNTIES
TODAY...WITH HIGHEST POPS DURING THE AFTERNOON AND ACROSS THE
SOUTHERN HALF OF THE FORECAST AREA. LARGELY DISORGANIZED
MULTICELLULAR CONVECTION ONCE AGAIN FAVORED IN THE ABSENCE OF BL
SHEAR...WITH TORRENTIAL RAINFALL AND LOCALIZED FLOODING THE PRIMARY
IMPACT AS STORM MOTIONS WILL BE GENERALLY 10KTS OR LESS.
TEMPS...DEPENDING ON HOW QUICKLY STORMS GET GOING...POTENTIAL EXISTS
FOR TEMPS TO OVERACHIEVE A BIT TODAY. WENT AT OR JUST ABOVE WARMER
MAVMOS.
&&
.SHORT TERM /TONIGHT THROUGH SATURDAY NIGHT/...
ISSUED AT 317 AM EDT THU MAY 29 2014
FORECAST CHALLENGES ARE FEW THROUGH THE PERIOD...AS HIGH PRESSURE
ASSERTS CONTROL OVER THE REGION FOR MUCH OF THE SHORT TERM.
ANTICIPATE LINGERING CONVECTION FOCUSED OVER SOUTHERN COUNTIES NEAR
THE REMNANT FRONTAL BOUNDARY THIS EVENING...WITH STORMS DIMINISHING
BY MIDNIGHT AS THE AIRMASS STABILIZES AND PROGRESSIVELY DRIER AIR
SPREADS IN WITH THE HIGH PRESSURE TO THE NORTH. DEEPER MOISTURE AXIS
WILL REMAIN JUST TO THE SOUTHWEST OF THE FORECAST AREA ON
FRIDAY...CLOSE ENOUGH THAT AN ISOLATED STORM CANNOT BE ENTIRELY
RULED OUT OVER THE EXTREME SOUTHWEST FORECAST AREA. HOWEVER WITH
COVERAGE SPARSE AT BEST WILL MAINTAIN A DRY FORECAST.
OVER THE REMAINDER OF THE FORECAST AREA...THE SURFACE HIGH WILL TAKE
ROOT WITH STRONG RIDGING ALOFT ESTABLISHING AS WELL. MODEL SOUNDINGS
AND RH PROGS INDICATE DEEP SUBSIDENCE ACCOMPANYING THE HIGH WITH
ABUNDANT SUNSHINE ANTICIPATED FRIDAY AND SATURDAY AS A PREDOMINANT
DRY E/NE FLOW CONTINUES. ALL IN ALL...SHAPING UP TO BE A GREAT
WEEKEND FOR CENTRAL INDIANA.
TEMPS...DESPITE SLIGHTLY COOLER 850MB TEMPS FRIDAY AND SATURDAY...
PRESENCE OF THE UPPER RIDGE AND ABUNDANT SUNSHINE WILL COMPENSATE
WITH HIGHS INTO THE 80S FRIDAY AND SATURDAY. LEANED TOWARDS WARMER
MAVMOS GUIDANCE BOTH DAYS. EXPECT LOWS INTO THE 50S IN SOME OF OUR
NORMAL COOL SPOTS BOTH TONIGHT AND FRIDAY NIGHT...ESPECIALLY NORTH
AND EAST OF THE INDY METRO. WENT ABOVE GUIDANCE AT INDY FOR LOWS
TONIGHT AND FRIDAY NIGHT WITH A LIGHT E/NE FLOW.
&&
.LONG TERM /SUNDAY THROUGH WEDNESDAY/...
ISSUED AT 317 AM EDT THU MAY 29 2014
AN UPPER RIDGE OVER CENTRAL INDIANA WILL MOVE EAST AND WIND UP OFF
THE EAST COAST BY THE END OF THE LONG TERM. AN UPPER TROUGH OVER THE
WESTERN U.S. WILL ALLOW WEAK SHORTWAVES TO MOVE THROUGH THE FLOW AND
BRING THUNDERSTORM CHANCES TO CENTRAL INDIANA THROUGHOUT THE LONG
TERM. WITH THE SOUTHWESTERLY FLOW OVER THE AREA CONDITIONS WILL
REMAIN WARM AND HUMID AS THE GULF REMAINS OPEN. NO STRONG FEATURES
TO FOCUS ON SO STUCK WITH INITIALIZATION CHANCE POPS FROM SUNDAY
NIGHT ON. FOR SUNDAY MORNING THE UPPER RIDGE WILL JUST BE STARTING
TO MOVE EAST AND THUS THINK PRECIPITATION WILL HAVE A HARD TIME
MOVING EAST INTO THE AREA UNDER UPPER SUBSIDENCE. THUS WENT DRY FOR
SUNDAY MORNING AND BROUGHT IN LOW CHANCE POPS IN THE WEST IN THE
AFTERNOON.
&&
.AVIATION /DISCUSSION FOR 291200Z TAF ISSUANCE/...
ISSUED AT 652 AM EDT THU MAY 29 2014
COULD HAVE AN HOUR OR SO OF MVFR FOG AT THE OUTLYING SITES. AT KLAF
SHOULD SEE IFR CEILINGS STICK AROUND FOR A COUPLE HOURS BEFORE IT
MIXES UP AND SCATTERS OUT. AFTER THAT WILL SEE SOME CHANCES FOR
THUNDERSTORMS DURING THE AFTERNOON AND EVENING AT ALL BUT KLAF WITH
THE COLD FRONT SLOWLY SINKING SOUTH THROUGH CENTRAL/SOUTHERN
INDIANA. HRRR AND RAP SHOW QPF DEVELOPING ALONG/SOUTH OF I-70
STARTING AFTER 18Z OR SO AND LASTING THROUGH AROUND 1Z AND INCLUDED
VCTS DURING THIS TIME. COULD SEE MVFR VISIBILITIES AND POSSIBLY
CEILINGS DEVELOP AGAIN DURING THE OVERNIGHT HOURS. WINDS LESS THAN
10 KTS THROUGH THE PERIOD.
&&
.IND WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...RYAN
NEAR TERM...SMF/RYAN
SHORT TERM...RYAN
LONG TERM....CP
AVIATION...CP
VISIT US AT HTTP://WWW.WEATHER.GOV/IND
FOLLOW US ON TWITTER AND YOUTUBE AT:
WWW.TWITTER.COM/NWSINDIANAPOLIS
WWW.YOUTUBE.COM/NWSINDIANAPOLIS
AREA FORECAST DISCUSSION
NWS INDIANAPOLIS IN
653 AM EDT THU MAY 29 2014
.UPDATE...
THE AVIATION SECTION HAS BEEN UPDATED BELOW.
&&
.SYNOPSIS...
ISSUED AT 317 AM EDT THU MAY 29 2014
SCATTERED THUNDERSTORMS ARE EXPECTED ONCE AGAIN TODAY AS A SLOW
MOVING FRONT DROPS SOUTH. THE FRONT WILL EVENTUALLY SLIP SOUTH OF
THE OHIO RIVER TONIGHT AS STRONG HIGH PRESSURE BUILDS IN FROM THE
NORTH. WARM DRY WEATHER IS ANTICIPATED INTO SUNDAY AS THE HIGH
CENTERS OVER THE REGION. A MORE UNSETTLED PATTERN RETURNS FOR THE
FIRST HALF OF NEXT WEEK WITH CHANCES FOR THUNDERSTORMS.
&&
.NEAR TERM /TODAY/...
ISSUED AT 317 AM EDT THU MAY 29 2014
ANOTHER STICKY MORNING WITH PLENTY OF CLOUD DEBRIS ACROSS THE
REGION. CONVECTION HAS LARGELY DIMINISHED WITH THE EXCEPTION OF A
SMALL PERSISTENT CELL NEAR KMIE WHICH WAS FINALLY WEAKENING. TEMPS
WERE GENERALLY IN THE 60S AS OF 07Z WITH PATCHY FOG DEVELOPING IN
AREAS THAT RECEIVED RAIN ON WEDNESDAY.
THE CATALYSTS FOR CONVECTIVE DEVELOPMENT WILL BE THE SAME AS THEY
HAVE BEEN THE LAST FEW DAYS...MODEST INSTABILITY AND THE PRESENCE OF
THE SLOWLY SOUTHWARD MOVING FRONTAL BOUNDARY. A REMNANT OUTFLOW
BOUNDARY THAT APPEARS TO BE LOCATED FROM NEAR KHUF SOUTHEAST TO KBMG
AND SEYMOUR IS THE WILDCARD TODAY...AS IT WILL LIKELY BE A FOCAL
POINT FOR STORMS TO FIRE ONCE CONVECTIVE TEMPS ARE MET BY EARLY
AFTERNOON. SHORT RANGE MODEL GUIDANCE ALSO HINTING AT A WEAK AXIS OF
MID LEVEL FORCING ALIGNING NORTHWEST-SOUTHEAST ACROSS THE CENTER OF
THE FORECAST AREA THIS AFTERNOON BEFORE GRADUALLY SHIFTING SOUTH.
WHILE THE GREATEST CONVECTIVE COVERAGE WILL BE FOUND PRIMARILY SOUTH
OF I-70...THE PRESENCE OF THE WEAK FORCING ALOFT SUPPORTS SCATTERED
CONVECTION ALL THE WAY NORTH TO A CRAWFORDSVILLE-NOBLESVILLE-
ANDERSON LINE. HRRR AND WRF REFLECTIVITY PROGS FOR THIS AFTERNOON
BOTH SUPPORT THIS IDEA IN THE 18-21Z TIME PERIOD BEFORE SHIFTING
STORMS SOUTH AS DRIER AIR ATTEMPTS TO ADVECT IN FROM THE NORTHEAST.
WILL CARRY CHANCE POPS FOR ALL BUT THE FAR NORTHERN COUNTIES
TODAY...WITH HIGHEST POPS DURING THE AFTERNOON AND ACROSS THE
SOUTHERN HALF OF THE FORECAST AREA. LARGELY DISORGANIZED
MULTICELLULAR CONVECTION ONCE AGAIN FAVORED IN THE ABSENCE OF BL
SHEAR...WITH TORRENTIAL RAINFALL AND LOCALIZED FLOODING THE PRIMARY
IMPACT AS STORM MOTIONS WILL BE GENERALLY 10KTS OR LESS.
TEMPS...DEPENDING ON HOW QUICKLY STORMS GET GOING...POTENTIAL EXISTS
FOR TEMPS TO OVERACHIEVE A BIT TODAY. WENT AT OR JUST ABOVE WARMER
MAVMOS.
&&
.SHORT TERM /TONIGHT THROUGH SATURDAY NIGHT/...
ISSUED AT 317 AM EDT THU MAY 29 2014
FORECAST CHALLENGES ARE FEW THROUGH THE PERIOD...AS HIGH PRESSURE
ASSERTS CONTROL OVER THE REGION FOR MUCH OF THE SHORT TERM.
ANTICIPATE LINGERING CONVECTION FOCUSED OVER SOUTHERN COUNTIES NEAR
THE REMNANT FRONTAL BOUNDARY THIS EVENING...WITH STORMS DIMINISHING
BY MIDNIGHT AS THE AIRMASS STABILIZES AND PROGRESSIVELY DRIER AIR
SPREADS IN WITH THE HIGH PRESSURE TO THE NORTH. DEEPER MOISTURE AXIS
WILL REMAIN JUST TO THE SOUTHWEST OF THE FORECAST AREA ON
FRIDAY...CLOSE ENOUGH THAT AN ISOLATED STORM CANNOT BE ENTIRELY
RULED OUT OVER THE EXTREME SOUTHWEST FORECAST AREA. HOWEVER WITH
COVERAGE SPARSE AT BEST WILL MAINTAIN A DRY FORECAST.
OVER THE REMAINDER OF THE FORECAST AREA...THE SURFACE HIGH WILL TAKE
ROOT WITH STRONG RIDGING ALOFT ESTABLISHING AS WELL. MODEL SOUNDINGS
AND RH PROGS INDICATE DEEP SUBSIDENCE ACCOMPANYING THE HIGH WITH
ABUNDANT SUNSHINE ANTICIPATED FRIDAY AND SATURDAY AS A PREDOMINANT
DRY E/NE FLOW CONTINUES. ALL IN ALL...SHAPING UP TO BE A GREAT
WEEKEND FOR CENTRAL INDIANA.
TEMPS...DESPITE SLIGHTLY COOLER 850MB TEMPS FRIDAY AND SATURDAY...
PRESENCE OF THE UPPER RIDGE AND ABUNDANT SUNSHINE WILL COMPENSATE
WITH HIGHS INTO THE 80S FRIDAY AND SATURDAY. LEANED TOWARDS WARMER
MAVMOS GUIDANCE BOTH DAYS. EXPECT LOWS INTO THE 50S IN SOME OF OUR
NORMAL COOL SPOTS BOTH TONIGHT AND FRIDAY NIGHT...ESPECIALLY NORTH
AND EAST OF THE INDY METRO. WENT ABOVE GUIDANCE AT INDY FOR LOWS
TONIGHT AND FRIDAY NIGHT WITH A LIGHT E/NE FLOW.
&&
.LONG TERM /SUNDAY THROUGH WEDNESDAY/...
ISSUED AT 317 AM EDT THU MAY 29 2014
AN UPPER RIDGE OVER CENTRAL INDIANA WILL MOVE EAST AND WIND UP OFF
THE EAST COAST BY THE END OF THE LONG TERM. AN UPPER TROUGH OVER THE
WESTERN U.S. WILL ALLOW WEAK SHORTWAVES TO MOVE THROUGH THE FLOW AND
BRING THUNDERSTORM CHANCES TO CENTRAL INDIANA THROUGHOUT THE LONG
TERM. WITH THE SOUTHWESTERLY FLOW OVER THE AREA CONDITIONS WILL
REMAIN WARM AND HUMID AS THE GULF REMAINS OPEN. NO STRONG FEATURES
TO FOCUS ON SO STUCK WITH INITIALIZATION CHANCE POPS FROM SUNDAY
NIGHT ON. FOR SUNDAY MORNING THE UPPER RIDGE WILL JUST BE STARTING
TO MOVE EAST AND THUS THINK PRECIPITATION WILL HAVE A HARD TIME
MOVING EAST INTO THE AREA UNDER UPPER SUBSIDENCE. THUS WENT DRY FOR
SUNDAY MORNING AND BROUGHT IN LOW CHANCE POPS IN THE WEST IN THE
AFTERNOON.
&&
.AVIATION /DISCUSSION FOR 291200Z TAF ISSUANCE/...
ISSUED AT 652 AM EDT THU MAY 29 2014
COULD HAVE AN HOUR OR SO OF MVFR FOG AT THE OUTLYING SITES. AT KLAF
SHOULD SEE IFR CEILINGS STICK AROUND FOR A COUPLE HOURS BEFORE IT
MIXES UP AND SCATTERS OUT. AFTER THAT WILL SEE SOME CHANCES FOR
THUNDERSTORMS DURING THE AFTERNOON AND EVENING AT ALL BUT KLAF WITH
THE COLD FRONT SLOWLY SINKING SOUTH THROUGH CENTRAL/SOUTHERN
INDIANA. HRRR AND RAP SHOW QPF DEVELOPING ALONG/SOUTH OF I-70
STARTING AFTER 18Z OR SO AND LASTING THROUGH AROUND 1Z AND INCLUDED
VCTS DURING THIS TIME. COULD SEE MVFR VISIBILITIES AND POSSIBLY
CEILINGS DEVELOP AGAIN DURING THE OVERNIGHT HOURS. WINDS LESS THAN
10 KTS THROUGH THE PERIOD.
&&
.IND WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...RYAN
NEAR TERM...RYAN
SHORT TERM...RYAN
LONG TERM....CP
AVIATION...CP
VISIT US AT HTTP://WWW.WEATHER.GOV/IND
FOLLOW US ON TWITTER AND YOUTUBE AT:
WWW.TWITTER.COM/NWSINDIANAPOLIS
WWW.YOUTUBE.COM/NWSINDIANAPOLIS
AREA FORECAST DISCUSSION
NWS INDIANAPOLIS IN
435 AM EDT THU MAY 29 2014
.UPDATE...
THE AVIATION SECTION HAS BEEN UPDATED BELOW.
&&
.SYNOPSIS...
ISSUED AT 317 AM EDT THU MAY 29 2014
SCATTERED THUNDERSTORMS ARE EXPECTED ONCE AGAIN TODAY AS A SLOW
MOVING FRONT DROPS SOUTH. THE FRONT WILL EVENTUALLY SLIP SOUTH OF
THE OHIO RIVER TONIGHT AS STRONG HIGH PRESSURE BUILDS IN FROM THE
NORTH. WARM DRY WEATHER IS ANTICIPATED INTO SUNDAY AS THE HIGH
CENTERS OVER THE REGION. A MORE UNSETTLED PATTERN RETURNS FOR THE
FIRST HALF OF NEXT WEEK WITH CHANCES FOR THUNDERSTORMS.
&&
.NEAR TERM /TODAY/...
ISSUED AT 317 AM EDT THU MAY 29 2014
ANOTHER STICKY MORNING WITH PLENTY OF CLOUD DEBRIS ACROSS THE
REGION. CONVECTION HAS LARGELY DIMINISHED WITH THE EXCEPTION OF A
SMALL PERSISTENT CELL NEAR KMIE WHICH WAS FINALLY WEAKENING. TEMPS
WERE GENERALLY IN THE 60S AS OF 07Z WITH PATCHY FOG DEVELOPING IN
AREAS THAT RECEIVED RAIN ON WEDNESDAY.
THE CATALYSTS FOR CONVECTIVE DEVELOPMENT WILL BE THE SAME AS THEY
HAVE BEEN THE LAST FEW DAYS...MODEST INSTABILITY AND THE PRESENCE OF
THE SLOWLY SOUTHWARD MOVING FRONTAL BOUNDARY. A REMNANT OUTFLOW
BOUNDARY THAT APPEARS TO BE LOCATED FROM NEAR KHUF SOUTHEAST TO KBMG
AND SEYMOUR IS THE WILDCARD TODAY...AS IT WILL LIKELY BE A FOCAL
POINT FOR STORMS TO FIRE ONCE CONVECTIVE TEMPS ARE MET BY EARLY
AFTERNOON. SHORT RANGE MODEL GUIDANCE ALSO HINTING AT A WEAK AXIS OF
MID LEVEL FORCING ALIGNING NORTHWEST-SOUTHEAST ACROSS THE CENTER OF
THE FORECAST AREA THIS AFTERNOON BEFORE GRADUALLY SHIFTING SOUTH.
WHILE THE GREATEST CONVECTIVE COVERAGE WILL BE FOUND PRIMARILY SOUTH
OF I-70...THE PRESENCE OF THE WEAK FORCING ALOFT SUPPORTS SCATTERED
CONVECTION ALL THE WAY NORTH TO A CRAWFORDSVILLE-NOBLESVILLE-
ANDERSON LINE. HRRR AND WRF REFLECTIVITY PROGS FOR THIS AFTERNOON
BOTH SUPPORT THIS IDEA IN THE 18-21Z TIME PERIOD BEFORE SHIFTING
STORMS SOUTH AS DRIER AIR ATTEMPTS TO ADVECT IN FROM THE NORTHEAST.
WILL CARRY CHANCE POPS FOR ALL BUT THE FAR NORTHERN COUNTIES
TODAY...WITH HIGHEST POPS DURING THE AFTERNOON AND ACROSS THE
SOUTHERN HALF OF THE FORECAST AREA. LARGELY DISORGANIZED
MULTICELLULAR CONVECTION ONCE AGAIN FAVORED IN THE ABSENCE OF BL
SHEAR...WITH TORRENTIAL RAINFALL AND LOCALIZED FLOODING THE PRIMARY
IMPACT AS STORM MOTIONS WILL BE GENERALLY 10KTS OR LESS.
TEMPS...DEPENDING ON HOW QUICKLY STORMS GET GOING...POTENTIAL EXISTS
FOR TEMPS TO OVERACHIEVE A BIT TODAY. WENT AT OR JUST ABOVE WARMER
MAVMOS.
&&
.SHORT TERM /TONIGHT THROUGH SATURDAY NIGHT/...
ISSUED AT 317 AM EDT THU MAY 29 2014
FORECAST CHALLENGES ARE FEW THROUGH THE PERIOD...AS HIGH PRESSURE
ASSERTS CONTROL OVER THE REGION FOR MUCH OF THE SHORT TERM.
ANTICIPATE LINGERING CONVECTION FOCUSED OVER SOUTHERN COUNTIES NEAR
THE REMNANT FRONTAL BOUNDARY THIS EVENING...WITH STORMS DIMINISHING
BY MIDNIGHT AS THE AIRMASS STABILIZES AND PROGRESSIVELY DRIER AIR
SPREADS IN WITH THE HIGH PRESSURE TO THE NORTH. DEEPER MOISTURE AXIS
WILL REMAIN JUST TO THE SOUTHWEST OF THE FORECAST AREA ON
FRIDAY...CLOSE ENOUGH THAT AN ISOLATED STORM CANNOT BE ENTIRELY
RULED OUT OVER THE EXTREME SOUTHWEST FORECAST AREA. HOWEVER WITH
COVERAGE SPARSE AT BEST WILL MAINTAIN A DRY FORECAST.
OVER THE REMAINDER OF THE FORECAST AREA...THE SURFACE HIGH WILL TAKE
ROOT WITH STRONG RIDGING ALOFT ESTABLISHING AS WELL. MODEL SOUNDINGS
AND RH PROGS INDICATE DEEP SUBSIDENCE ACCOMPANYING THE HIGH WITH
ABUNDANT SUNSHINE ANTICIPATED FRIDAY AND SATURDAY AS A PREDOMINANT
DRY E/NE FLOW CONTINUES. ALL IN ALL...SHAPING UP TO BE A GREAT
WEEKEND FOR CENTRAL INDIANA.
TEMPS...DESPITE SLIGHTLY COOLER 850MB TEMPS FRIDAY AND SATURDAY...
PRESENCE OF THE UPPER RIDGE AND ABUNDANT SUNSHINE WILL COMPENSATE
WITH HIGHS INTO THE 80S FRIDAY AND SATURDAY. LEANED TOWARDS WARMER
MAVMOS GUIDANCE BOTH DAYS. EXPECT LOWS INTO THE 50S IN SOME OF OUR
NORMAL COOL SPOTS BOTH TONIGHT AND FRIDAY NIGHT...ESPECIALLY NORTH
AND EAST OF THE INDY METRO. WENT ABOVE GUIDANCE AT INDY FOR LOWS
TONIGHT AND FRIDAY NIGHT WITH A LIGHT E/NE FLOW.
&&
.LONG TERM /SUNDAY THROUGH WEDNESDAY/...
ISSUED AT 317 AM EDT THU MAY 29 2014
AN UPPER RIDGE OVER CENTRAL INDIANA WILL MOVE EAST AND WIND UP OFF
THE EAST COAST BY THE END OF THE LONG TERM. AN UPPER TROUGH OVER THE
WESTERN U.S. WILL ALLOW WEAK SHORTWAVES TO MOVE THROUGH THE FLOW AND
BRING THUNDERSTORM CHANCES TO CENTRAL INDIANA THROUGHOUT THE LONG
TERM. WITH THE SOUTHWESTERLY FLOW OVER THE AREA CONDITIONS WILL
REMAIN WARM AND HUMID AS THE GULF REMAINS OPEN. NO STRONG FEATURES
TO FOCUS ON SO STUCK WITH INITIALIZATION CHANCE POPS FROM SUNDAY
NIGHT ON. FOR SUNDAY MORNING THE UPPER RIDGE WILL JUST BE STARTING
TO MOVE EAST AND THUS THINK PRECIPITATION WILL HAVE A HARD TIME
MOVING EAST INTO THE AREA UNDER UPPER SUBSIDENCE. THUS WENT DRY FOR
SUNDAY MORNING AND BROUGHT IN LOW CHANCE POPS IN THE WEST IN THE
AFTERNOON.
&&
.AVIATION /DISCUSSION FOR 290900Z TAF UPDATE/...
ISSUED AT 435 AM EDT THU MAY 29 2014
COULD SEE SOME MVFR FOG AT ALL THE SITES STARTING AROUND 9-10Z AND
MIXING OUT BY 12-13Z. ALSO COULD SEE SOME IFR CEILINGS AND
VISIBILITIES AT KLAF BASED ON SATELLITE LOOP SHOWING AREA OF LOW
CEILINGS NEAR KOKOMO ADVECTING WEST AND THIS COULD LAST THROUGH MID
MORNING. OTHER THAN THAT...CONDITIONS SHOULD BE MOSTLY VFR THROUGH
EVENING WITH CU AND AC. SOME CHANCES FOR THUNDERSTORMS IN THE
AFTERNOON BUT LOW ENOUGH PROBABILITY TO LEAVE OUT AT THIS TIME.
COLD FRONT SHOULD SINK SOUTH PAST BMG AROUND OR SHORTLY AFTER 12Z.
STILL...WINDS WILL BE LESS THAN 10 KNOTS THROUGH THE PERIOD.
&&
.IND WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
SYNOPSIS...RYAN
NEAR TERM...RYAN
SHORT TERM...RYAN
LONG TERM....CP
AVIATION...MK/CP
VISIT US AT HTTP://WWW.WEATHER.GOV/IND
FOLLOW US ON TWITTER AND YOUTUBE AT:
WWW.TWITTER.COM/NWSINDIANAPOLIS
WWW.YOUTUBE.COM/NWSINDIANAPOLIS
AREA FORECAST DISCUSSION
NWS INDIANAPOLIS IN
317 AM EDT THU MAY 29 2014
.UPDATE...
THE SYNOPSIS...NEAR TERM...SHORT TERM AND LONG TERM SECTIONS HAVE
BEEN UPDATED BELOW.
&&
.SYNOPSIS...
ISSUED AT 317 AM EDT THU MAY 29 2014
SCATTERED THUNDERSTORMS ARE EXPECTED ONCE AGAIN TODAY AS A SLOW
MOVING FRONT DROPS SOUTH. THE FRONT WILL EVENTUALLY SLIP SOUTH OF
THE OHIO RIVER TONIGHT AS STRONG HIGH PRESSURE BUILDS IN FROM THE
NORTH. WARM DRY WEATHER IS ANTICIPATED INTO SUNDAY AS THE HIGH
CENTERS OVER THE REGION. A MORE UNSETTLED PATTERN RETURNS FOR THE
FIRST HALF OF NEXT WEEK WITH CHANCES FOR THUNDERSTORMS.
&&
.NEAR TERM /TODAY/...
ISSUED AT 317 AM EDT THU MAY 29 2014
ANOTHER STICKY MORNING WITH PLENTY OF CLOUD DEBRIS ACROSS THE
REGION. CONVECTION HAS LARGELY DIMINISHED WITH THE EXCEPTION OF A
SMALL PERSISTENT CELL NEAR KMIE WHICH WAS FINALLY WEAKENING. TEMPS
WERE GENERALLY IN THE 60S AS OF 07Z WITH PATCHY FOG DEVELOPING IN
AREAS THAT RECEIVED RAIN ON WEDNESDAY.
THE CATALYSTS FOR CONVECTIVE DEVELOPMENT WILL BE THE SAME AS THEY
HAVE BEEN THE LAST FEW DAYS...MODEST INSTABILITY AND THE PRESENCE OF
THE SLOWLY SOUTHWARD MOVING FRONTAL BOUNDARY. A REMNANT OUTFLOW
BOUNDARY THAT APPEARS TO BE LOCATED FROM NEAR KHUF SOUTHEAST TO KBMG
AND SEYMOUR IS THE WILDCARD TODAY...AS IT WILL LIKELY BE A FOCAL
POINT FOR STORMS TO FIRE ONCE CONVECTIVE TEMPS ARE MET BY EARLY
AFTERNOON. SHORT RANGE MODEL GUIDANCE ALSO HINTING AT A WEAK AXIS OF
MID LEVEL FORCING ALIGNING NORTHWEST-SOUTHEAST ACROSS THE CENTER OF
THE FORECAST AREA THIS AFTERNOON BEFORE GRADUALLY SHIFTING SOUTH.
WHILE THE GREATEST CONVECTIVE COVERAGE WILL BE FOUND PRIMARILY SOUTH
OF I-70...THE PRESENCE OF THE WEAK FORCING ALOFT SUPPORTS SCATTERED
CONVECTION ALL THE WAY NORTH TO A CRAWFORDSVILLE-NOBLESVILLE-
ANDERSON LINE. HRRR AND WRF REFLECTIVITY PROGS FOR THIS AFTERNOON
BOTH SUPPORT THIS IDEA IN THE 18-21Z TIME PERIOD BEFORE SHIFTING
STORMS SOUTH AS DRIER AIR ATTEMPTS TO ADVECT IN FROM THE NORTHEAST.
WILL CARRY CHANCE POPS FOR ALL BUT THE FAR NORTHERN COUNTIES
TODAY...WITH HIGHEST POPS DURING THE AFTERNOON AND ACROSS THE
SOUTHERN HALF OF THE FORECAST AREA. LARGELY DISORGANIZED
MULTICELLULAR CONVECTION ONCE AGAIN FAVORED IN THE ABSENCE OF BL
SHEAR...WITH TORRENTIAL RAINFALL AND LOCALIZED FLOODING THE PRIMARY
IMPACT AS STORM MOTIONS WILL BE GENERALLY 10KTS OR LESS.
TEMPS...DEPENDING ON HOW QUICKLY STORMS GET GOING...POTENTIAL EXISTS
FOR TEMPS TO OVERACHIEVE A BIT TODAY. WENT AT OR JUST ABOVE WARMER
MAVMOS.
&&
.SHORT TERM /TONIGHT THROUGH SATURDAY NIGHT/...
ISSUED AT 317 AM EDT THU MAY 29 2014
FORECAST CHALLENGES ARE FEW THROUGH THE PERIOD...AS HIGH PRESSURE
ASSERTS CONTROL OVER THE REGION FOR MUCH OF THE SHORT TERM.
ANTICIPATE LINGERING CONVECTION FOCUSED OVER SOUTHERN COUNTIES NEAR
THE REMNANT FRONTAL BOUNDARY THIS EVENING...WITH STORMS DIMINISHING
BY MIDNIGHT AS THE AIRMASS STABILIZES AND PROGRESSIVELY DRIER AIR
SPREADS IN WITH THE HIGH PRESSURE TO THE NORTH. DEEPER MOISTURE AXIS
WILL REMAIN JUST TO THE SOUTHWEST OF THE FORECAST AREA ON
FRIDAY...CLOSE ENOUGH THAT AN ISOLATED STORM CANNOT BE ENTIRELY
RULED OUT OVER THE EXTREME SOUTHWEST FORECAST AREA. HOWEVER WITH
COVERAGE SPARSE AT BEST WILL MAINTAIN A DRY FORECAST.
OVER THE REMAINDER OF THE FORECAST AREA...THE SURFACE HIGH WILL TAKE
ROOT WITH STRONG RIDGING ALOFT ESTABLISHING AS WELL. MODEL SOUNDINGS
AND RH PROGS INDICATE DEEP SUBSIDENCE ACCOMPANYING THE HIGH WITH
ABUNDANT SUNSHINE ANTICIPATED FRIDAY AND SATURDAY AS A PREDOMINANT
DRY E/NE FLOW CONTINUES. ALL IN ALL...SHAPING UP TO BE A GREAT
WEEKEND FOR CENTRAL INDIANA.
TEMPS...DESPITE SLIGHTLY COOLER 850MB TEMPS FRIDAY AND SATURDAY...
PRESENCE OF THE UPPER RIDGE AND ABUNDANT SUNSHINE WILL COMPENSATE
WITH HIGHS INTO THE 80S FRIDAY AND SATURDAY. LEANED TOWARDS WARMER
MAVMOS GUIDANCE BOTH DAYS. EXPECT LOWS INTO THE 50S IN SOME OF OUR
NORMAL COOL SPOTS BOTH TONIGHT AND FRIDAY NIGHT...ESPECIALLY NORTH
AND EAST OF THE INDY METRO. WENT ABOVE GUIDANCE AT INDY FOR LOWS
TONIGHT AND FRIDAY NIGHT WITH A LIGHT E/NE FLOW.
&&
.LONG TERM /SUNDAY THROUGH WEDNESDAY/...
ISSUED AT 317 AM EDT THU MAY 29 2014
AN UPPER RIDGE OVER CENTRAL INDIANA WILL MOVE EAST AND WIND UP OFF
THE EAST COAST BY THE END OF THE LONG TERM. AN UPPER TROUGH OVER THE
WESTERN U.S. WILL ALLOW WEAK SHORTWAVES TO MOVE THROUGH THE FLOW AND
BRING THUNDERSTORM CHANCES TO CENTRAL INDIANA THROUGHOUT THE LONG
TERM. WITH THE SOUTHWESTERLY FLOW OVER THE AREA CONDITIONS WILL
REMAIN WARM AND HUMID AS THE GULF REMAINS OPEN. NO STRONG FEATURES
TO FOCUS ON SO STUCK WITH INITIALIZATION CHANCE POPS FROM SUNDAY
NIGHT ON. FOR SUNDAY MORNING THE UPPER RIDGE WILL JUST BE STARTING
TO MOVE EAST AND THUS THINK PRECIPITATION WILL HAVE A HARD TIME
MOVING EAST INTO THE AREA UNDER UPPER SUBSIDENCE. THUS WENT DRY FOR
SUNDAY MORNING AND BROUGHT IN LOW CHANCE POPS IN THE WEST IN THE
AFTERNOON.
&&
.AVIATION /DISCUSSION FOR 290600Z TAF ISSUANCE/...
ISSUED AT 1253 AM EDT THU MAY 29 2014
WOULD NOT RULE OUT A STRAY THUNDERSTORM OVERNIGHT...BUT CHANCES ARE
LOW ENOUGH THAT WILL NOT PUT IN ANY OF THE TAFS. COULD SEE SOME MVFR
FOG AFTER 09Z...OTHER THAN THAT...CONDITIONS SHOULD BE MOSTLY VFR
THROUGH TOMORROW EVENING WITH CU AND AC.
COLD FRONT SHOULD BE NEAR OR SOUTH OF HUF AND IND AT ISSUANCE TIME
AND BMG LIKELY AROUND OR SHORTLY AFTER 12Z. STILL...WINDS WILL BE
LESS THAN 10 KNOTS THROUGH THE PERIOD.
&&
.IND WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
SYNOPSIS...RYAN
NEAR TERM...RYAN
SHORT TERM...RYAN
LONG TERM....CP
AVIATION...MK/CP
VISIT US AT HTTP://WWW.WEATHER.GOV/IND
FOLLOW US ON TWITTER AND YOUTUBE AT:
WWW.TWITTER.COM/NWSINDIANAPOLIS
WWW.YOUTUBE.COM/NWSINDIANAPOLIS
AREA FORECAST DISCUSSION
NWS NORTHERN INDIANA
200 AM EDT THU MAY 29 2014
.SYNOPSIS...
ISSUED AT 155 AM EDT THU MAY 29 2014
A RIDGE OF HIGH PRESSURE WILL SLOWLY SAG INTO THE REGION TODAY
PROVIDING MAINLY DRY CONDITIONS. SCATTERED SHOWERS AND ISOLATED
THUNDERSTORMS WILL BE POSSIBLE ONCE AGAIN FROM CENTRAL ILLINOIS
INTO CENTRAL INDIANA. THIS RIDGE OF HIGH PRESSURE WILL PROVIDE DRY
CONDITIONS THROUGH MOST OF THE UPCOMING WEEKEND. HIGH TEMPERATURES
ON THURSDAY WILL RANGE FROM THE MID 70S TO AROUND 80. LOW
TEMPERATURES THURSDAY NIGHT WILL DROP INTO THE LOWER AND MID 50S.
&&
.SHORT TERM...(THIS EVENING THROUGH THURSDAY)
ISSUED AT 336 PM EDT WED MAY 28 2014
LOOSELY DEFINED "COLD" FRONT...MORE ACCURATELY DESCRIBED AS A WEAK
SURFACE PRESSURE TROUGH WITH A MODEST MOISTURE/DENSITY
GRADIENT...CONTINUES TO SLOWLY PUSH SOUTH ACROSS THE AREA AT PRESS
TIME. AS PREVIOUSLY NOTED...VERY LITTLE SYNOPTIC SUPPORT ALONG THIS
FRONT WITH JUST A VERY WEAK VORTICITY LOBE WINDING DOWN ACROSS THE
REGION. SHOWERS AND THUNDERSTORMS BEING DRIVEN BY SUBTLE CONVERGENCE
ALONG OLD OUTFLOW/DIFFERENTIAL HEATING BOUNDARIES IN A MOIST AND
MARGINALLY UNSTABLE AIRMASS. EARLY DAY INSOLATION ALLOWED FOR A
DECENT RISE IN MLCAPE VALUES ACROSS OUR SOUTHERN COUNTIES WHILE FAR
NORTHERN ZONES REMAIN LARGELY CAPPED AND STABLE. NUMEROUS SHOWERS
AND THUNDERSTORMS HAVE THEREFORE DEVELOPED IN OUR SOUTHERN CWA AS
EXPECTED. LACK OF APPRECIABLE SHEAR AND/OR CLEAR FORCING MECHANISM
WILL CONTINUE TO SUPPORT PULSE/MULTICELLULAR MODE THROUGH THE
EVENING. AN ISOLATED WET MICROBURST MAY BE POSSIBLE ONCE AGAIN BUT
THREAT FOR MORE WIDESPREAD SEVERE WEATHER IS VERY LOW. HEAVY RAIN IS
STILL THE MAIN THREAT WITH HIGH PW VALUES...WEAK FLOW PARALLEL TO
THE FRONT...AND MORE EFFICIENT WARM RAIN PROCESSES. HRRR AND OTHER
HI-RES GUIDANCE HAVE HAD A VERY GOOD HANDLE ON CONVECTION SO FAR
TODAY AND SUGGEST THUNDERSTORMS WILL DISSIPATE AND DRIFT SOUTH BY
AROUND 03Z WITH THE LOSS OF DAYTIME HEATING AND GRADUAL SOUTHWARD
PUSH OF FRONT. DRY CONDITIONS THEN EXPECTED FOR THE REST OF THE
PERIOD AS HIGH AMPLITUDE RIDGE FOLDS INTO THE GREAT LAKES AND
SUPPORTS SURFACE HIGH PRESSURE. A STRAY SHOWER MAY BE POSSIBLE
TOMORROW MORNING IN OUR FAR SOUTHERN COUNTIES BUT CHANCES ARE VERY
LOW. THERMAL PROFILES BEHIND THIS FRONT ARE NOT VERY DIFFERENT FROM
CURRENT VALUES AND EXPECT INCREASING SUN TO SUPPORT ANOTHER DAY OF
HIGHS NEAR 80F. DEWPOINTS WILL BE TOUCH LOWER THOUGH...TAKING THE
HUMIDITY DOWN A NOTCH.
&&
.LONG TERM...(THURSDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 336 PM EDT WED MAY 28 2014
LONG WAVE PATTERN WITH HIGHLY AMPLIFIED RIDGE OVER THE CENTRAL US
WILL START THE LONG TERM PERIOD. TROF ALONG THE NOAM WEST COAST
EJECTS EASTWARD AND WHILE MODELS DIFFER ON THE TIMING AND
EVOLUTION THERE IS ENOUGH CONSENSUS TO SUPPORT A FLATTENING OF THE
RIDGE OVER THE GREAT LAKES REGION TOWARD THE END OF THE LONG TERM
PERIOD.
THE CHALLENGE IS THE SIGNIFICANT DIFFERENCE BETWEEN THE 06Z AND 12Z
GFS RUN. 12Z MODEL IS MORE CLOSELY ALIGNED WITH THE GEM/ECMWF AND
UKMET - THE 06Z AS THE OUTLIER HAD THE LOW EJECTING FROM THE PLAINS
IN WHAT APPEARS TO BE MUCH TO FAST AND TOO FAR SOUTH.
REGARDLESS WITH ABUNDANT LOW LEVEL MOISTURE AND THE AREA WITHIN THE
WARM SECTOR...EXPECT TO SEE CONVECTION DEVELOP AS CURRENTLY FORECAST
AND SHOULD NOT CAUSE A DRAMATIC CHANGE TO CURRENT GRIDDED FORECAST.
AS THE RIDGE FLATTENS AND WESTERLY FLOW INCREASES WOULD EXPECT TO
SEE THE FRONTAL BOUNDARY PUSH SOUTH OF THE AREA DURING THE LATTER
PART OF THE EXTENDED PERIOD...WITH SLIGHT COOLING. TEMPERATURES
SHOULD STILL REMAIN ABOVE NORMAL THROUGH THE PERIOD.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z THURSDAY NIGHT)
ISSUED AT 155 AM EDT THU MAY 29 2014
PATCHY STRATUS IS EXPECTED TO CONTINUE OVERNIGHT WITH LINGERING
LOW LEVEL MOISTURE AND FAIRLY WEAK GRADIENT IN PLACE. MVFR
CONDITIONS ARE CURRENTLY BEING REPORTED AT TERMINALS...AND MAY SEE
SOME BUILD DOWN OF THIS STRATUS OVERNIGHT. THUS...WILL MAINTAIN
TREND TO IFR CIGS OVERNIGHT FROM PREVIOUS FORECAST. ANY LINGERING
IFR OR MVFR CONDITIONS WILL IMPROVE TO VFR BY MID MORNING
THURSDAY. DRY AIR ADVECTION ASSOCIATED WITH SFC TROUGH WILL KEEP
FOCUS FOR ISOLD/SCT AFTERNOON SHOWERS SOUTH OF THE TERMINALS.
NORTHEAST WINDS TO CONTINUE THROUGH THIS PERIOD WITH SPEEDS
GENERALLY AT OR BELOW 10 KNOTS.
&&
.IWX WATCHES/WARNINGS/ADVISORIES...
IN...NONE.
MI...NONE.
OH...NONE.
LM...NONE.
&&
$$
SYNOPSIS...MARSILI
SHORT TERM...AGD
LONG TERM...LEWIS
AVIATION...MARSILI
VISIT US AT WWW.WEATHER.GOV/IWX (ALL LOWER CASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
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WWW.TWITTER.COM/NWSIWX
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AREA FORECAST DISCUSSION
NWS INDIANAPOLIS IN
1253 AM EDT THU MAY 29 2014
.UPDATE...
THE AVIATION SECTION HAS BEEN UPDATED BELOW.
&&
.SYNOPSIS...
ISSUED AT 328 PM EDT WED MAY 28 2014
A WEAK COLD FRONT WILL MOVE THROUGH CENTRAL INDIANA TONIGHT AND
THURSDAY BRINGING SOME SHOWERS AND THUNDERSTORMS WITH IT. FRIDAY AND
SATURDAY WILL BE DRY WITH HIGH PRESSURE IN CONTROL...BUT CHANCES FOR
RAIN RETURN FOR LATE SUNDAY INTO NEXT WEEK AS ANOTHER SYSTEM BEGINS
TO INFLUENCE THE AREA. TEMPERATURES WILL REMAIN WARM THROUGH THE
PERIOD.
&&
.NEAR TERM /OVERNIGHT/...
ISSUED AT 923 PM EDT WED MAY 28 2014
SURFACE ANALYSIS EARLY THIS EVENING SHOWS A SLOWING FRONTAL
BOUNDARY NEAR INTERSTATE 70. RAIN COOLED AIR NORTH OF THE FRONT
HAS RESULTED IN COOLER TEMPS...LOWER DEW POINTS AND MORE STABLE
AIR. SOUTH OF THE FRONT...THE AIR MASS REMAINED UNSTABLE AND SCT
SHRA/TSRA WERE DEVELOPING. HOWEVER...WITH HEATING WANING...ANY
SHOWERS OR STORMS THAT DEVELOP ARE EXPECTED TO WEAKEN QUICKLY
DURING THE NEXT SEVERAL HOURS. HRRR AGREES. AS FOR TEMPS HAVE
TRENDED LOWS A BIT COOLER IN THE RAIN COOLED AIR MASS TO THE
NORTH...AND STUCK WARMER AHEAD OF THE FRONT TO THE SOUTH.
&&
.SHORT TERM /THURSDAY THROUGH SATURDAY/...
ISSUED AT 328 PM EDT WED MAY 28 2014
FOCUS IS ON CHANCES FOR RAIN EARLY IN THE PERIOD. MODELS ARE CLOSE
ENOUGH THAT A BLEND CAN BE USED.
WITH FRONT IN THE AREA ON THURSDAY CONTINUED CHANCE POPS MOST
AREAS...HIGHEST IN THE SOUTH CLOSEST TO THE FRONT. DO NOT SEE ENOUGH
FORCING FOR LIKELY OR HIGHER POPS WITH NO UPPER SUPPORT. TIMING OF
BEST CHANCES WILL BE LATE MORNING INTO AFTERNOON AS INSTABILITY
BUILDS.
AS FRONT CONTINUES ITS SLOW JOURNEY SOUTH KEPT LINGERING SLIGHT
CHANCE TO LOW CHANCE POPS IN THE SOUTHWEST FORECAST AREA THURSDAY
EVENING. FRONT SHOULD BE FAR ENOUGH SOUTH AND INSTABILITY LOW ENOUGH
OVERNIGHT THURSDAY FOR DRY POPS.
ON FRIDAY AND SATURDAY UPPER HIGH WILL BUILD IN AND PROVIDE DRY
CONDITIONS.
GENERALLY TRENDED TOWARD THE MAV MOS THROUGH THE PERIOD AS MET LOOKS
A BIT COOL WITH NO GOOD SHOT OF COOLER AIR MOVING IN.
&&
.LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/...
ISSUED AT 213 PM EDT WED MAY 28 2014
HIGH PRESSURE OVER THE EASTERN U.S. AND AN UPPER RIDGE OF HIGH
PRESSURE MOVING EAST OF OUR AREA WHILE UPPER TROUGHING DEVELOPS OVER
THE WESTERN STATES SPELLS WARM TEMPERATURES AND RETURN OF GULF
MOISTURE AND HIGHER HUMIDITY BY SUNDAY NIGHT. MINOR SHORT WAVES
MOVING THROUGH THE FLOW MEAN TIMING ISSUES FOR PRECIPITATION AND
HARD TO PINPOINT MOST LIKELY WINDOWS OF OPPORTUNITY FOR RAIN. HAVE
THUS CARRIED CHANCE POPS FOR NEARLY ALL PERIODS STARTING SUNDAY
WHICH ACTUALLY TIES TO ALL MODEL SOLUTIONS OF SOME PRECIPITATION
POSSIBLE DAY OR NIGHT INTO MIDWEEK.
AS FOR TEMPERATURES...WITH ABOVE NORMAL HEIGHTS AND INCREASING
DEWPOINTS STARTING SUNDAY EXPECT MAXS AND MINS TO BE ABOVE NORMAL
FOR THIS TIME OF YEAR. NO SIGNIFICANT ADJUSTMENTS TO CURRENT
FORECAST TEMPS WERE MADE...USING A MIX OF MOS DATA AND BLENDED
SETS.
&&
.AVIATION /DISCUSSION FOR 290600Z TAF ISSUANCE/...
ISSUED AT 1253 AM EDT THU MAY 29 2014
WOULD NOT RULE OUT A STRAY THUNDERSTORM OVERNIGHT...BUT CHANCES ARE
LOW ENOUGH THAT WILL NOT PUT IN ANY OF THE TAFS. COULD SEE SOME MVFR
FOG AFTER 09Z...OTHER THAN THAT...CONDITIONS SHOULD BE MOSTLY VFR
THROUGH TOMORROW EVENING WITH CU AND AC.
COLD FRONT SHOULD BE NEAR OR SOUTH OF HUF AND IND AT ISSUANCE TIME
AND BMG LIKELY AROUND OR SHORTLY AFTER 12Z. STILL...WINDS WILL BE
LESS THAN 10 KNOTS THROUGH THE PERIOD.
&&
.IND WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...50
NEAR TERM...PUMA
SHORT TERM...50
LONG TERM....TUCEK
AVIATION...MK/CP
VISIT US AT HTTP://WWW.WEATHER.GOV/IND
FOLLOW US ON TWITTER AND YOUTUBE AT:
WWW.TWITTER.COM/NWSINDIANAPOLIS
WWW.YOUTUBE.COM/NWSINDIANAPOLIS
AREA FORECAST DISCUSSION
NWS SHREVEPORT LA
1100 AM CDT THU MAY 29 2014
.DISCUSSION...
THE UPPER LOW REMAINS CENTERED OVER EXTREME SE AR THIS MORNING...WITH
THE SHORT TERM PROGS IN GENERAL AGREEMENT WITH THE LOW WOBBLING OVER
THIS AREA AND NE LA THROUGH THE AFTERNOON BEFORE SLOWLY RETROGRADING W
INTO SW AR/NW LA TONIGHT. A 40NM MILE WIDE BAND OF CONVECTION OVER
SCNTRL AND NE LA AHEAD OF THE LOW HAS NOT SHOWN ANY WWD BACKBUILDING
INTO THE ERN SECTIONS OF NCNTRL LA THIS MORNING...WITH THE HRRR AND
12Z NAM MAINTAINING THIS CONVECTION JUST E OF THE REGION THROUGH AT
LEAST EARLY AFTERNOON BEFORE SHUNTING IT E ACROSS THE MS RIVER.
HOWEVER...VISIBLE SATELLITE DOES REVEAL TOWERS DEVELOPING OVER MUCH OF
THE REGION...WITH A MORE AGITATED CU FIELD NEAR/NW OF THE CLOSED LOW
OVER WCNTRL AR/SE OK. WITH ADDED HEATING...SHOULD SEE SCT CONVECTION
DEVELOP WITHIN THE NEXT HOUR OR SO OVER THESE AREAS...WHICH WOULD
SHIFT SSW INTO EXTREME NE TX/SW AR/NW LA DURING THE AFTERNOON.
DID REDUCE POPS THIS MORNING AREAWIDE GIVEN THE LACK OF CONVECTION
ATTM...AND ALSO TONED DOWN POPS SLIGHTLY /TO LIKELY/ ACROSS SCNTRL
AR/ERN SECTIONS OF NCNTRL LA. MID/HIGH CHANCE POPS SHOULD SUFFICE OVER
MUCH OF E TX/WCNTRL LA...FARTHER AWAY FROM THE CENTER OF THE CLOSED
LOW. MUCH OF THIS CONVECTION SHOULD WIND DOWN THIS EVENING WITH THE
LOSS OF HEATING.
DID MAKE MINOR ADJUSTMENTS TO MAX TEMPS THIS AFTERNOON...MAINLY TO
LOWER THEM A COUPLE DEGREES ACROSS SW AR...AND ALSO RAISING THEM
SLIGHTLY ACROSS THE WRN SECTIONS OF E TX WHICH ARE ALREADY IN THE
MID/UPPER 70S AS OF 1530Z. OTHERWISE...THE REMAINDER OF THE FORECAST
IS ON TRACK.
ZONE UPDATE ALREADY OUT...GRIDS WILL BE AVAILABLE SHORTLY.
15
&&
.PRELIMINARY POINT TEMPS/POPS...
SHV 81 68 83 68 86 / 60 30 70 30 50
MLU 80 67 82 67 86 / 70 30 70 30 50
DEQ 79 67 83 67 85 / 60 30 70 30 40
TXK 80 67 83 67 86 / 60 40 70 40 50
ELD 78 67 83 66 86 / 70 40 60 30 50
TYR 84 68 83 68 85 / 40 20 60 40 30
GGG 82 68 83 68 86 / 40 30 60 40 30
LFK 84 68 83 69 86 / 30 30 60 30 40
&&
.SHV WATCHES/WARNINGS/ADVISORIES...
AR...NONE.
LA...NONE.
OK...NONE.
TX...NONE.
&&
$$
15
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
1019 AM EDT THU MAY 29 2014
.SYNOPSIS...
A SLOW MOVING COLD FRONT WILL STALL ACROSS THE EASTERN CAROLINAS
TODAY AND FRIDAY...CREATING WIDESPREAD SHOWERS AND THUNDERSTORMS.
HIGH PRESSURE WILL BUILD DOWN FROM THE NORTH OVER THE WEEKEND
BRINGING DRIER AND COOLER AIR TO THE REGION. THIS HIGH PRESSURE WILL
PUSH OFFSHORE ON MONDAY...WITH A WARMING TREND EXPECTED INTO THE
MIDDLE OF NEXT WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 10:20 AM THURSDAY...ANALYSIS OF MORNING SOUNDINGS AND LATEST
DATA CONFIRM A MODERATELY TO STRONGLY UNSTABLE AND MOIST AIRMASS
TODAY WITH WEAK VERTICAL SHEAR AND A BOUNDARY-RICH ENVIRONMENT.
ALSO...A COLD FRONT CONTINUES TO STEADILY ADVANCE SOUTH AND IS NOW
ENTERING PENDER COUNTY. THIS CONFIRMS EARLIER PROGNOSIS...SEE
DISCUSSION BELOW...OF A CONVECTIVE-LY ACTIVE AFTERNOON AND EVENING
WITH PULSE-TYPE CONVECTION BRINGING THE THREAT OF HEAVY
RAIN...FREQUENT LIGHTNING AND DAMAGING WINDS. LATEST HRRR DATA AND
MODEL SOUNDINGS INDICATE STORMS WILL BEGIN TO FIRE UP IN THE 1 TO
2 PM TIME-FRAME. FORECAST REMAINS ON TRACK. SEE PREVIOUS
DISCUSSION BELOW:
A COLD FRONT CURRENTLY DROPPING SOUTH EAST-CENTRAL NORTH CAROLINA
WILL REACH SOUTHEASTERN NORTH CAROLINA BY NOON...SLOWING AND
PRACTICALLY STALLING AS SUCH FRONTS OFTEN DO DURING INTENSE SOLAR
HEATING. THIS FRONT IS A SEPARATE ENTITY FROM A CONVECTIVE OUTFLOW
BOUNDARY WHICH HAS STALLED IN THE VICINITY OF THE NC/SC STATE
LINE. THIS OUTFLOW BOUNDARY ORIGINATED FROM A LARGE CLUSTER OF
OVERNIGHT STORMS IN NORTHEASTERN NORTH CAROLINA. THE BOUNDARY WAS
EARLIER VISIBLE ON RADAR LOOPS AND ALTHOUGH IS DIFFICULT TO FIND
NOW...IT WILL ALMOST CERTAINLY BECOME VISIBLE THIS AFTERNOON WHEN
STORMS BEGIN TO FIRE.
THE ENVIRONMENT SHOULD BECOME MODERATELY TO STRONGLY UNSTABLE THIS
AFTERNOON WITH SURFACE-BASED CAPE RISING TO 2000-3000 J/KG AND
LIFTED INDICES FALLING TO NEAR -7. SYNOPTIC SCALE LOW-LEVEL
CONVERGENCE WILL BECOME MAXIMIZED ALONG THE STALLED FRONT. THE
ADDITION OF THE SEABREEZE BOUNDARY AND THE OLD OUTFLOW BOUNDARY
SHOULD GIVE PLENTY OF POTENTIAL TRIGGERS FOR STORMS TO DEVELOP.
LAPSE RATES WILL BE PARTICULARLY STEEP UP THROUGH 650 MB...INDUCING
LARGE INITIAL PARCEL ACCELERATION AND A RAPID ERUPTION OF STORMS
ONCE CONVECTIVE TEMPERATURES ARE REACHED. FORECAST POPS TODAY RANGE
FROM 70 PERCENT ACROSS INTERIOR SE NORTH CAROLINA TO 40 PERCENT
ALONG THE SANTEE RIVER...GRADUALLY TAPERING DOWN LATE THIS EVENING
AS CONVECTIVE OVERTURNING STABILIZES THE ATMOSPHERE.
MID AND UPPER LEVEL WINDS WILL BE EXCEEDINGLY WEAK TODAY...5-8 KT AT
850 MB...5-10 KT AT 500 MB...AND AROUND 10 KT AT 300 MB. THIS SHOULD
PROMOTE SINGLE-CELL STORMS WITH VERY LITTLE ORGANIZATION. STORMS
WILL CHOKE ON THEIR OWN COLD OUTFLOW BUT BOUNDARY COLLISIONS SHOULD
EASILY CREATE A NUMBER OF NEW CELLS. VERY SLOW CELL MOTION WILL
PRODUCE A PATCHWORK OF VERY HEAVY RAINFALL AMOUNTS...POSSIBLY 2-3
INCHES IN ISOLATED SPOTS...INTERSPERSED WITH LIGHTER TOTALS. HIGH
WINDS FROM WET MICRO BURSTS WILL BE THE MAIN SEVERE WEATHER THREAT
WITH A POTENTIAL OF ISOLATED HAIL AS WELL. THESE STORMS COULD ALSO
BECOME VERY PROLIFIC LIGHTNING PRODUCERS SINCE THEORETICAL
PARCEL-MINUS-ENVIRONMENTAL TEMPERATURE DIFFERENCES SHOULD REMAIN
LARGE (6-8 DEGREES C) UP THROUGH THE -10 TO -30C LAYER.
HIGH TEMPERATURES SHOULD REACH THE UPPER 80S TO AROUND 90
TODAY...WARMEST ACROSS THE SC PEE DEE REGION. LOWS TONIGHT SHOULD
FALL INTO THE UPPER 60S FOR MOST AREAS.
&&
.SHORT TERM /FRIDAY THROUGH SATURDAY NIGHT/...
AS OF 300 AM THURSDAY...INTERESTING PATTERN FOR THE SHORT TERM...AS
AMPLIFIED AND BLOCKED 5H FLOW FORCES SYSTEMS TO RETROGRADE ALOFT.
TWO LARGE UPPER LOWS...ONE NEARLY STATIONARY ACROSS THE ARKLATEX
REGION...AND ANOTHER RE-STRENGTHENING OVER SOUTHEAST CANADA...WILL
CONTINUE THEIR LOCAL INFLUENCES INTO THE WKND...WITH THE CAROLINAS
REMAINING SANDWICHED BETWEEN THE TWO. ATOP THE ARKLATEX LOW...A
RIDGE OF HIGH PRESSURE BLOSSOMING NEAR THE GREAT LAKES WILL BE
FORCED SOUTHEAST TOWARDS THE AREA ON SATURDAY AS IT...ALMOST
LITERALLY...GETS SQUEEZED OUT BY THE NORTHEAST TROUGH...FORCING THE
ARKLATEX LOW TO RETROGRADE AND WEAKEN ACROSS EAST TEXAS. AT THE
SURFACE...A BACK DOOR TYPE COLD FRONT WILL SINK SLOWLY ACROSS THE
AREA FRIDAY...DROPPING SOUTH LATE SATURDAY...AS ITS MOTION GETS BOTH
ASSISTED (BY NORTHEAST TROUGH) AND IMPEDED (BY UPPER
RIDGE)...CAUSING ITS SLOW PROGRESSION. THIS FRONT WILL BE THE
IMPETUS FOR CONVECTION EACH DAY...AND THE MAIN CHALLENGE FOR TEMPS
AS WELL.
FRIDAY LOOKS TO BE THE MORE ACTIVE...AND WARMER DAY OF THE SHORT
TERM. FRONT WILL BE ROUGHLY BISECTING THE CWA...ALIGNED EAST TO WEST
NEAR THE SC/NC LINE...FRIDAY MORNING. THE AIR MASS IMMEDIATELY
BEHIND THIS FEATURE IS NOT DRASTICALLY DIFFERENT THAN THAT AHEAD OF
IT...SO WHILE TEMPS ACROSS THE NORTHERN HALF OF THE CWA WILL BE
SLIGHTLY COOLER THAN THOSE IN THE SOUTH...STILL EXPECT HIGHS IN THE
LOW/MID 80S NORTH...MID/UPR 80S SOUTH. LOWS FRIDAY NIGHT WILL DROP
TO NEAR CLIMO VALUES...LOW/MID 60S...HIGHEST IN THE SOUTHERN
ZONES.
MORE SIGNIFICANTLY...SHOWERS/TSTMS ARE EXPECTED TO BE WIDESPREAD ON
FRIDAY...AS EVIDENCED BY A LARGE SWATH OF 90% 12-HR SREF PROBS FOR
0.01 INCHES ACROSS THE AREA. THE HIGHEST PROBS ARE ACROSS SC...BUT
THE ENTIRE CWA IS LIKELY TO SEE CONVECTION ON FRIDAY. SBCAPE VALUES
RISE TO AROUND 1500 J/KG SOUTH OF THE FRONT...BUT RAPIDLY FALL OFF
BEHIND IT. A SIMILAR PWAT GRADIENT EXISTS AS WELL...FROM ABOUT 1.9
INCHES WELL SOUTH...TO 1.3 INCHES FAR NORTH...IN A COLUMN
CHARACTERIZED BY AROUND 10 KFT OF WARM CLOUD DEPTH. THIS SETUP
SUPPORTS VERY HEAVY RAIN POTENTIAL...AS EFFICIENT PRECIPITATION
PROCESSES ARE LIKELY DUE TO MODERATELY STRONG UPDRAFTS INTO A DEEPLY
SATURATED COLUMN. ALTHOUGH LAPSE RATES ARE NOT VERY
IMPRESSIVE...CREATING LOW NORMALIZED-CAPE VALUES...THIS HAS BEEN
SHOWN TO FURTHER ENHANCE PRECIPITATION EFFICIENCY...AND THUS HEAVY
RAINFALL WILL BE THE PRIMARY RISK ON FRIDAY...ESPECIALLY NOTING
THE ADDED CAVEAT OF SLOW STORM MOTIONS. AT THE SAME TIME...A MID-
LEVEL IMPULSE IS PROGGED TO ROTATE DOWN WITHIN THE NW
FLOW...MOVING ATOP THE FRONT DURING THE LATE AFTN...WHICH WILL
ONLY ACT TO ENHANCE COVERAGE AND INTENSITY OF SHOWERS/STORMS. THIS
SUGGESTS THE STRONGEST CONVECTION WILL BE IN THE SOUTHERN THIRD OF
THE CWA...AND HIGHEST POP...LIKELY...WILL BE SHOWN
THERE...TRENDING DOWN TO CHC IN THE NORTH. WITH THIS SETUP IN
PLACE...AND THURSDAY EXPECTED TO BE WET AS WELL...LOCALIZED
FLOODING MAY BECOME A CONCERN...ESPECIALLY ACROSS SOUTH CAROLINA
ZONES...AND THIS WILL NEED TO BE MONITORED CLOSELY DURING THE NEXT
DAY.
A QUIETER DAY SATURDAY...BUT WITH THE FRONT STILL SLOWLY SINKING
SOUTH...SOME DIURNALLY ENHANCED SHOWERS/TSTMS ARE
POSSIBLE...ESPECIALLY IN THE PEE DEE REGION AND ALONG THE SOUTH
SANTEE RIVER. PROFILES SHOW PRETTY QUICK DRYING FROM NORTH TO SOUTH
THROUGH THE DAY...SO BEST PRECIP CHANCES WILL BE EARLY IN THE
AFTN...WITH POP DROPPING TO SILENT BY THE EVENING. TEMPS WILL BE
COOLER BY A FEW DEGREES BEHIND THE FRONT...LOW/MID 80S AREA-WIDE
WITH LOWS POTENTIALLY FALLING BELOW 60 IN THE FAR NORTH SATURDAY
NIGHT...LOW 60S ELSEWHERE.
&&
.LONG TERM /SUNDAY THROUGH WEDNESDAY/...
AS OF 300 AM THURSDAY...UPPER RIDGE DROPS ACROSS THE AREA EARLY IN
THE PERIOD...BEFORE FLATTENING INTO THE MIDDLE OF NEXT WEEK. AT THE
SURFACE...COOL HIGH PRESSURE DROPS SOUTH OUT OF NEW ENGLAND ON
SUNDAY BEFORE MOVING OVERHEAD EARLY NEXT WEEK AND THEN OFFSHORE LATE
IN THE EXTENDED. THIS PATTERN PRODUCES MOSTLY QUIET WEATHER WITH
SEASONABLE TO SLIGHTLY BELOW CLIMO TEMPS SUN/MON AND WITH MUCH
DECREASED HUMIDITY. ALTHOUGH THE UPPER PATTERN FLATTENS NEXT
WEEK...THE HIGH PRESSURE MOVING OFFSHORE WILL BEGIN TO DRIVE
WARM/MOIST RETURN FLOW BACK INTO THE CAROLINAS TUE/WED. WHILE TEMPS
ARE NOT EXPECTED TO REACH WELL ABOVE NORMAL LEVELS LIKE WE SAW
FREQUENTLY IN MAY...SLIGHTLY ABOVE CLIMO VALUES ARE EXPECTED FOR THE
MIDDLE OF NEXT WEEK...ALONG WITH SLOWLY INCREASING DIURNAL TSTM
CHANCES.
&&
.AVIATION /14Z THURSDAY THROUGH MONDAY/...
AS OF 12Z...VFR WILL PREVAIL THROUGH THE AFTERNOON HOURS WITH THE
EXCEPTION OF SOME SHORT-LIVED PERIODS OF MARGINAL MVFR DUE TO FOG
THIS MORNING. PERIODS OF MVFR DUE TO FOG/REDUCED VSBYS IN ISOLATED
TO SCATTERED CONVECTION LATER TODAY AND TONIGHT POSSIBLE AS WELL.
VFR PREVAILS ACROSS THE AREA WITH LIGHT WINDS THIS MORNING...WITH THE
EXCEPTION OF MARGINAL MVFR DUE TO PATCHY FOG AT KILM ATTM. AN
APPROACHING COLD FRONT FROM THE NORTH WILL MOVE DOWN INTO THE AREA
TODAY...AND WITH AN OVERALL FAVORABLE ENVIRONMENT...ANTICIPATE
INCREASING CHANCES FOR SHOWERS AND THUNDERSTORMS THIS AFTERNOON AND
INTO THE EVENING HOURS. REDUCED RESTRICTIONS WILL BE POSSIBLE IN ANY
HEAVY DOWNPOUR OR PATCHY FOG. WEST WINDS THIS MORNING WILL SHIFT TO
THE EAST-NORTHEAST BY THIS AFTERNOON DEPENDING ON THE LOCATION OF
THE AFOREMENTIONED FRONTAL BOUNDARY. BUT OVERALL WINDS WILL BE AOB
10 KTS. INTO THE OVERNIGHT HOURS...ACTIVITY WILL TAPER OFF FOR THE
REMAINDER OF THE VALID TAF PERIOD WITH LIGHT WINDS...LOW CIGS AND
PATCHY FOG LIKELY...POSSIBLY CREATING MVFR/IFR CONDITIONS THROUGH
THE END OF THE PERIOD.
EXTENDED OUTLOOK...SCATTERED SHOWERS/TSTMS WITH BRIEF PERIODS OF
SUB-VFR CONDITIONS EXPECTED THROUGH FRIDAY...MAINLY IN THE AFTERNOON
AND EARLY EVENING HOURS. VFR SATURDAY THROUGH MONDAY.
&&
.MARINE...
NEAR TERM /THROUGH TONIGHT/...
AS OF 10:20 AM THURSDAY...NO CHANGES TO THE FORECAST WITH THE
LATEST UPDATE. PREVIOUS DISCUSSION FOLLOWS:
A COLD FRONT RECENTLY MOVED SOUTH OF CAPE LOOKOUT AND SHOULD REACH
SOUTHEASTERN NORTH CAROLINA NORTH OF CAPE FEAR BEFORE NOON. THE
FRONT SHOULD THEN STALL AND TEMPORARILY BECOME DIFFUSE WITH THE
DEVELOPING AFTERNOON SEABREEZE CIRCULATION. THIS SHOULD LEAD TO A
VARIETY OF WIND DIRECTIONS ACROSS THE COASTAL WATERS: MAINLY
NORTHEAST NORTH OF CAPE FEAR...AND MAINLY SOUTHWEST SOUTH OF CAPE
FEAR...BUT WITH THE SEABREEZE DETERMINING THE EVENTUAL DIRECTION.
FAIRLY WIDESPREAD THUNDERSTORMS SHOULD DEVELOP INLAND THIS
AFTERNOON. VERY SLOW MOVEMENT MEANS MOST OF THESE STORM CELLS WILL
REMAIN INLAND ON THE WEST SIDE OF THE SEABREEZE...HOWEVER A FEW
COULD DRIFT OUT PAST THE BEACHES INTO THE NEARSHORE WATERS. ANY
STORMS WILL BE ACCOMPANIED BY GUSTY WINDS AND A GOOD DEAL OF
LIGHTNING.
THE FRONT SHOULD SINK SOUTHWARD INTO THE MYRTLE BEACH/MURRELLS INLET
AREA OVERNIGHT. AS INLAND THUNDERSTORMS DIE DOWN DURING THE EVENING
THERE IS THE POTENTIAL THE CONVECTIVE RISK COULD SHIFT OFFSHORE.
SEAS CURRENTLY AROUND 2 FEET SHOULD CHANGE LITTLE THROUGH TONIGHT
WITH MAINLY LIGHT WINDS EITHER SIDE OF THE FRONT. OBVIOUSLY NEAR ANY
THUNDERSTORMS WINDS AND SEAS COULD TEMPORARILY BUILD QUITE A BIT
HIGHER.
SHORT TERM /THURSDAY THROUGH FRIDAY NIGHT/...
AS OF 300 AM THURSDAY...SLOW MOVING BACK DOOR COLD FRONT WILL DROP
SOUTH ACROSS THE WATERS...BUT WILL TAKE UNTIL SATURDAY MORNING TO
MAKE IT ALL THE WAY SOUTH OF THE AREA. THIS WILL CREATE LIGHT AND
VARIABLE WINDS ON FRIDAY...FROM THE NE ON THE NORTH SIDE OF THIS
FRONT...AND THE S/SE TO THE SOUTH. BY SATURDAY...ALL WINDS WILL
BECOME N/NE WITH A WEAK SURGE CAUSING AN INCREASE IN SPEED TO 10-15
KTS. SEAS FRIDAY WILL BE PRIMARILY 1-2 FT...BUT WILL START TO RISE
TOWARDS 3 FT FRIDAY NIGHT ACROSS THE NC WATERS. SATURDAY SEAS WILL
BE DRIVEN BY THE ENHANCED NE WINDS...BECOMING 2-4 FT ALL WATERS.
LONG TERM /SATURDAY THROUGH MONDAY/...
AS OF 300 AM THURSDAY... HIGH PRESSURE BUILDING DOWN THE COAST WILL
DRIVE A PINCHED GRADIENT OVER THE WATERS ON SUNDAY...WITH NE WINDS
OF AROUND 15 KTS COMMON THROUGH THE DAY. THIS HIGH WILL BUILD DOWN
ACROSS THE WATERS SUNDAY NIGHT...THEN DRIFT OFFSHORE
MONDAY...CAUSING WINDS TO WEAKEN AND VEER SLOWLY...TO THE SW AT 5-10
KTS BY THE END OF THE PERIOD. SEAS OF 2-4 FT ARE EXPECTED SUNDAY
WITH A NE WIND CHOP PREDOMINANT WITHIN THE WAVE SPECTRUM. WAVE
HEIGHTS FALL TO 2-3 FT MONDAY AS THE WINDS EASE.
&&
.ILM WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
NC...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...TRA/JDW
NEAR TERM...REK/TRA
SHORT TERM...JDW
LONG TERM...JDW
AVIATION...SGL
MARINE...REK/TRA/JDW
AREA FORECAST DISCUSSION
NWS MEMPHIS TN
1029 AM CDT THU MAY 29 2014
.UPDATE...
AN UPPER LEVEL LOW PRESSURE SYSTEM WILL CONTINUE TO BRING
NUMEROUS SHOWERS WITH A FEW EMBEDDED THUNDERSTORMS TO THE MIDSOUTH
TODAY. LATEST HRRR SHOWS A BAND MOVING NORTHWARD FROM CENTRAL
MISSISSIPPI INTO NORTH MISSISSIPPI...THE MEMPHIS METRO AREA...AND
EVENTUALLY SPREADING INTO NORTHEAST ARKANSAS BETWEEN 1-4 PM. WILL UPDATE
TO EXPAND 80 POPS NORTHWARD TO COVER THIS AREA. WILL ALSO UPDATE
TO LOWER TEMPS DUE TO CLOUD COVER AND SHOWER ACTIVITY. UPDATE WILL
BE OUT SHORTLY.
KRM
&&
.DISCUSSION... /ISSUED 301 AM CDT THU MAY 29 2014/
CURRENT UPPER LOW WAS CENTERED OVER SOUTH CENTRAL ARKANSAS WITH
MODELS SUGGESTING THIS AS ITS CLOSEST POSITION TO THE MIDSOUTH
BEFORE SLOWLY DRIFTING SOUTHWESTWARD. ON THE SURFACE WINDS HAVE
BACKED TO A MORE EASTERLY COMPONENT AS AN INDUCED SURFACE LOW HAS
DEVELOPED IN THE SAME AREA. AS OF 3AM TEMPERATURES WERE BETWEEN
65F AND 70F...AND RADAR WAS SHOWING SCATTERED LIGHT SHOWERS
DRIFTING NORTHWARD OVER THE SOUTHWEST DELTA COUNTIES.
FOR TODAY AND TOMORROW...THE REGION WILL REMAIN INFLUENCED BY THE
CLOSED LOW WITH SCATTERED TO NUMEROUS SHOWERS ANTICIPATED DURING
THE HEAT OF THE DAY...AND LESS COVERAGE AT NIGHT. AGREED MODEL
CONSISTENCY POINTS TO THE REGION SOUTH AND WEST OF MEMPHIS WITH
THE GREATEST PROBABILITY OF PRECIPITATION...WHERE A WEAK INDUCED
INVERTED SURFACE TROUGH WILL FORM. THE HIGHEST QPF AMOUNTS WILL
BE OVER THIS AREA...WITH PERHAPS UP TO AN INCH AND HALF THROUGH
FRIDAY AFTERNOON. SIGNIFICANT CLOUD COVER WILL KEEP TEMPERATURES
BELOW NORMAL TODAY...AND CLOSER TO NORMAL TOMORROW. THIS...IN
ADDITION TO THE ONGOING MOIST ADIABATIC LAPSE RATES OFF FORECAST
SOUNDINGS SUGGESTS A REDUCTION IN THUNDERSTORM COVERAGE. A FEW
MORE BREAKS IN THE CLOUD COVER IS ANTICIPATED
TOMORROW...ESPECIALLY OVER THE NORTHERN HALF OF THE CWA AS THE LOW
CENTER MOVES TO NEAR LAKE SABINE IN WESTERN LOUISIANA. THEREFORE
THUNDERSTORM COVERAGE WILL REBOUND BACK...AND NORTH MISSISSIPPI
WILL STILL RUN THE GREATEST RISK FOR RAIN.
SATURDAY AND SUNDAY...NOT MUCH CHANGE WAS NEEDED WITH THE FORECAST
THIS PERIOD...WITH ONLY A SLIGHT INCREASE IN POPS AND A DEGREE
COOLER IN TEMPERATURES. THE REGION WILL REMAIN MOIST AS THE UPPER
LOW OPENS AND A WEAK SHEAR AXIS HANGS ALONG THE MISSISSIPPI RIVER.
LESS CLOUD COVER WILL ALLOW TEMPERATURES TO SHIFT BACK CLOSER TO
90F...WHICH MAY TRIGGER AN ISOLATED STRONG STORM DURING THE
AFTERNOON HOURS.
MONDAY THROUGH WEDNESDAY NIGHT...A SERIES OF WEAK SHORTWAVES WILL
CROSS THE ROCKIES AND THE MIDWEST WITH THE MIDSOUTH SHIFTING FROM
A LIGHT SOUTHEASTERLY/SOUTHERLY UPPER FLOW TO MORE WESTERLY. THE
ECMWF IS A BIT MORE BULLISH WITH QPF AMOUNTS OVER THE AREA FROM
FRONTAL MCS GENERATION IN THE MIDWEST...WHILE THE GFS KEEPS THE
WEAK FRONT AND CONVECTIVE CONCENTRATION IN THE CORN BELT. FOR NOW
HAVE KEPT RAIN CHANCES MORE CONSERVATIVE AND DIURNAL. TEMPERATURES
NEXT WEEK WILL REMAIN NEAR 90F FOR HIGHS AND 70F FOR LOWS...WITH A
SLIGHT SOUTHERLY BREEZE PROVIDING SOME RELIEF.
JAB
&&
.AVIATION...
12Z TAF CYCLE (29/12Z-30/12Z)
AN UPPER LEVEL LOW PRESSURE SYSTEM ALONG THE ARKANSAS AND LOUISIANA
BORDER WILL CONTINUE TO INFLUENCE MIDSOUTH WEATHER TODAY INTO
TONIGHT. SCATTERED TO NUMEROUS SHOWERS WILL OCCUR TODAY LASTING INTO
THIS EVENING. ALSO INCLUDED VCTS FOR THIS AFTERNOON AND EARLY
EVENING. MVFR TO IFR CONDITIONS WILL BECOME MAINLY MVFR BY 15Z THEN
PREDOMINATELY VFR BY 19Z OUTSIDE SHOWERS AND THUNDERSTORMS.
CONDITIONS LOWERING AGAIN AFTER 30/05Z TO MVFR AND IFR. WINDS
TODAY BECOMING SE-S 8-11 KTS...DECREASING TONIGHT TO 3-7 KTS AND
BECOMING MORE EASTERLY AT KJBR.
JCL
&&
&&
.MEG WATCHES/WARNINGS/ADVISORIES...
AR...NONE.
MO...NONE.
MS...NONE.
TN...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS BLACKSBURG VA
938 AM EDT THU MAY 29 2014
.SYNOPSIS...
LOW PRESSURE WAS IN SOUTHERN PENNSYLVANIA WITH A COLD FRONT
EXTENDING INTO NORTHEAST NORTH CAROLINA. THIS FRONT WILL MOVE
SOUTH TODAY AND STALL IN THE CAROLINAS TONIGHT. HIGH PRESSURE WILL
BUILD IN OVER THE EASTERN UNITED STATES BY THE WEEKEND WITH
SLIGHTLY COOLER AND DRIER AIR FOR SATURDAY AND SUNDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 921 AM EDT THURSDAY...
BACKDOOR COLD FRONT...HIGHLIGHTED NICELY BY MSAS ANALYSIS OF
LIFTED INDEX AND PRESSURE CHANGES...PUSHING INTO EASTERN PORTIONS
OF FORECAST AREA THIS MORNING. KFCX 88D SHOWED A FEW SHOWERS
MOVING EAST ACROSS THE NORTH. SATELLITE IMAGES INDICATED SUNSHINE
IN THE WEST WITH LOW CLOUDS ADVANCING WESTWARD TOWARDS BLUE RIDGE.
SFC OBS REPORT THAT IFR CLOUDS HAVE REACH LYH AND DAN THIS
MORNING. OUTSIDE THE LOW CLOUDS...TEMPERATURES HAVE CLIMB QUICKLY
THIS MORNING. MODIFIED TEMPERATURES AND HIGHS UP AS FEW DEGREES
WHERE READINGS ARE WARMER WITH ADDITIONAL SUNSHINE. STILL LOOKS
LIKE MOST LOCATIONS WILL BE CLOUDY BY 18Z THIS AFTERNOON. THE
COMBINATION OF LOW LEVEL CONVERGENCE ALONG THE SURFACE FRONT AND
THE LIFT FROM THE PASSING SHORT WAVE WILL RESULT IN SCATTERED TO
NUMEROUS SHOWERS AND THUNDERSTORMS THIS AFTERNOON AND EVENING. THE
LOCAL RNK WRFARW AND HRRR SUGGEST THAT MOST OF THE CONVECTION
STARTS AFTER 18Z THIS AFTERNOON...WITH NUMEROUS COVERAGE BY 00Z
THIS EVENING. MORE CHANGES LATER THIS MORNING...
AS OF 400 AM EDT THURSDAY...
500 MB PATTERN AMPLIFIES WITH A TROF ALONG THE EAST COAST DURING
THIS TIME FRAME. A SHORT WAVE AND ASSOCIATED JET STREAK CROSS FROM
THE OHIO VALLEY INTO NORTH CAROLINA BY MIDNIGHT.
MSAS ANALYSIS OF LIFTED INDEX AND PRESSURE CHANGES SHOWED FRONT WAS
JUST INTO THE EASTERN COUNTY WARNING AREA AT 3AM. MODELS BRING THE
BOUNDARY AS FAR WEST AS ROANOKE DURING THE DAY THEN EXPECTING THE
STABLE AIR TO ADVANCE DOWN THE EAST SLOPES OF THE BLUE
RIDGE...ALTHOUGH VERY SHALLOW OVERNIGHT. MOISTURE ABOVE 700MB GETS
PUSHED TO THE FAR SOUTHWEST COUNTIES OF THE FORECAST AREA BY
MORNING. BUT STILL AMPLE LOW LEVEL MOISTURE THROUGH TONIGHT.
THE COMBINATION OF LOW LEVEL CONVERGENCE ALONG THE SURFACE FRONT AND
THE LIFT FROM THE PASSING SHORT WAVE WILL RESULT IN SCATTERED TO
NUMEROUS SHOWERS THIS AFTERNOON AND EVENING. THE AIR MASS WEST OF
THE BOUNDARY WILL STILL BE UNSTABLE ENOUGH FOR THUNDERSTORMS. BUFKIT
FOR ROANOKE WAS ALSO SHOWING SUPPORT FOR ELEVATED CONVECTION TODAY.
CLOUDS...PRECIPITATION AND COOLER AIR MASS BEHIND THE FRONT WILL
LEAD TO COOLER MAXIMUM TEMPERATURES THAN PAST FEW DAYS IN THE EAST.
WESTERN PARTS OF THE COUNTY WARNING AREA THAT STILL GET ENOUGH SUN
WILL AGAIN REACH THE 80S FOR HIGHS. USED AN NON-DIURNAL
TEMPERATURES CURVE FOR TODAY AND STAYED CLOSE TO MET GUIDANCE FOR
MAXIMUM TEMPERATURES. ALSO USED SLIGHTLY COOLER MET FOR LOWS
TONIGHT.
&&
.SHORT TERM /FRIDAY THROUGH SUNDAY NIGHT/...
AS OF 400 AM EDT THURSDAY...
AN ABNORMAL PATTERN FOR LATE MAY...WITH A DEVELOPING REX BLOCK OVER
THE MISSISSIPPI RIVER VALLEY...AND A DEEPENING UPPER TROUGH OVER NEW
ENGLAND. VEERING THE EASTERLY FLOW TO THE S AND SW WILL BE A VERY
SLOW PROCESS...UNTIL THE NEW ENGLAND TROUGH FINALLY MOVES OFF THE
COAST AND THE UPPER RIDGE CLOSES OFF OVER THE SOUTHEAST BY MONDAY.
CONTINUED WHAT HAS BEEN A NIGHTLY TREND OF LOWERING MAX T JUST ABOUT
EACH DAY...ESPECIALLY BELOW THE MEX GUIDANCE WHICH JUST CAN`T HANDLE
THIS ODD ARRANGEMENT OF UPPER HIGHS AND LOWS. HIGHS TEMPS THROUGH
THIS PERIOD MAY FALL BELOW NORMAL...SAVE EXTREME SW VA AND SE WEST
VA. STILL SOME CLASHING OF AIRMASSES AND SURFACE CONVERGENCE KEEPS
SHOWERS/STORMS IN THE FORECAST THROUGH NW NC AND EXTREME SW VA ON
FRIDAY. ANOTHER STRONGER SURFACE HIGH ROLLING ACROSS THE LAKES AND
INTO NEW ENGLAND BY SUNDAY...WILL LIKELY KEEP ANY SHOWER
DEVELOPMENT SUPPRESSED TO NW NC...IF AT ALL SATURDAY AND SUNDAY.
MODELS HINTING AT SOME DRIZZLE/FOG/LIGHT RAIN SHOWERS BOTH FRIDAY
AND SATURDAY NIGHT WITH EASTERLY UPSLOPE FLOW ALONG THE BLUE
RIDGE. ALSO...CLOUDS WILL PROBABLY FILL BACK IN DURING THE
OVERNIGHTS...AS AFTERNOON MIXING ENDS.
&&
.LONG TERM /MONDAY THROUGH WEDNESDAY/...
AS OF 1245 PM EDT WEDNESDAY...
GOING TO BE HEADING BACK TO SUMMER TEMPS EARLY NEXT WEEK AS UPPER
RIDGE SITUATES ITSELF OVER THE WRN SIDE OF THE APPALACHIANS. BY
MIDWEEK...MODELS BREAK DOWN THE UPPER RIDGE AS TROUGH DIGS ACROSS
SRN CANADA. AT THE SFC...HIGH PRESSURE WORKS FROM THE MID ATLANTIC
TO THE SOUTHEAST COAST.
THE PATTERN SUGGESTS NO ORGANIZED SYSTEMS TO AFFECT US...BUT WILL
HAVE TO WATCH UPSTREAM ESPECIALLY TUE-WED AS THE 5H FLOW FLATTENS
FOR FASTER MOVING SHORTWAVES. OVERALL WILL BE TYPICAL SUMMER DIURNAL
RANGE IN SHRA/TSRA THREAT...WITH BEST CHANCES IN THE MOUNTAINS
ESPECIALLY TUE-WED. A LEE TROUGH SETS UP AS WELL OVER THE PIEDMONT
WHICH COULD AID IN STORM DEVELOPMENT.
FOR NOW KEEPING IN POPS IN THE CHANCE RANGE...WITH SUNDAY LOOKING
DRY.
&&
.AVIATION /13Z THURSDAY THROUGH MONDAY/...
AS OF 730 AM EDT THURSDAY...
MULTIPLE CHANGES IN WEATHER CONDITIONS ARE EXPECTED TODAY INTO
TONIGHT. CEILINGS HAVE LOWERED TO IFR BEHIND THE FRONT...INCLUDING
AT KLYH AND KDAN. EXPECT ONLY LIMITED IMPROVEMENT THROUGH
16Z/NOON...MAYBE TO MVFR.
A SHORT WAVE TRACKING OUT OF THE OHIO VALLEY WILL CROSS THE
REGION AND INTERACT WITH THE FRONT...LEADING TO NUMEROUS SHOWERS
AND SCATTERED THUNDERSTORMS. ONCE THIS FEATURE PASSES TO THE
SOUTHEAST...MUCH OF THE PRECIPITATION WILL BE LIMITED TO THE
EASTERN SLOPES OF THE BLUE RIDGE...WITH LIGHT RAIN OR DRIZZLE.
THERE MAY BE A BRIEF PERIOD OF VFR CEILINGS AND VISIBILITIES
AFTER THE BULK SHOWERS AND THUNDERSTORMS ENDS AND BEFORE SUNSET
BUT CONFIDENCE IS LOW ON THE TIMING ANY AMOUNT OF IMPROVEMENT.
AFTER 00Z CEILINGS WILL LOWER TO IFR. FOG WILL ALSO DEVELOP
OVERNIGHT... WITH THE LOWER VISIBILITIES EAST OF THE BLUE RIDGE.
SURFACE RIDGE OF HIGH PRESSURE GRADUALLY BUILDING IN BEHIND THE
FRONT FROM THE NORTHEAST WILL ALLOW FOR A SLOW RETURN TO VFR
CONDITIONS IN MOST AREAS BY FRIDAY NIGHT...BUT SOME LOCALIZED MVFR
RESTRICTIONS MAY STILL PERSIST INTO THE WEEKEND ACROSS THE
SOUTHWEST MOUNTAINS...MAINLY SOUTH OF KBLF. BY SUNDAY NIGHT AND
MONDAY THE ENTIRE REGION WILL TRANSITION BACK TO VFR CONDITIONS.
&&
.RNK WATCHES/WARNINGS/ADVISORIES...
VA...NONE.
NC...NONE.
WV...NONE.
&&
$$
SYNOPSIS...AMS
NEAR TERM...AMS/KK
SHORT TERM...KM
LONG TERM...WP
AVIATION...AMS/WERT
AREA FORECAST DISCUSSION
NWS DENVER/BOULDER CO
1049 AM MDT THU MAY 29 2014
...CORRECTED HYDRO SECTION...
.UPDATE...
ISSUED AT 1049 AM MDT THU MAY 29 2014
TEMPERATURES OVER THE EASTERN PLAINS ARE WARMER THAN FORECAST AS
THE SOUTHERLY WINDS HAVE BEEN INCREASING EARLY TODAY. HAVE
ADJUSTED THOSE TEMPERATURES. WEAK ECHOES OVER THE MOUNTAINS HAVE
BEEN APPEARING ON RADAR AS MORE SUN DUE TO LESS HIGH CLOUD COVER THAN
ORIGINALLY THOUGHT HAS OCCURRED. HAVE MOVED UP CHANCES OF
PRECIPITATION ACROSS THE MOUNTAINS AND URBAN CORRIDOR A COUPLE
HOURS.
NEW NAM AND HIGH RES RUC AND HRRR ARE SHOWING A PATTERN OF
AFTERNOON CONVECTION INCREASING WITH A SURGE OF MOISTURE MOVING UP
LATE THIS AFTERNOON FROM THE SOUTH PARK AREA....THEN ANOTHER WAVE
MOVING UP AROUND MIDNIGHT. WITH PRECIPITABLE WATER VALUES ALREADY
ABOUT 0.2 UP FROM YESTERDAY AND THE EXPECTED SLOW MOVING STORM
MOTIONS TO THE NORTHEAST...WILL KEEP AN EYE ON DEVELOPMENT AND
POTENTIAL FOR LOCALLY HEAVY RAIN.
&&
.SHORT TERM...(TODAY THROUGH TONIGHT )
ISSUED AT 246 AM MDT THU MAY 29 2014
HIGH LEVEL MOISTURE HAS BEEN SLOW TO SPREAD EASTWARD AS THE RIDGE
AXIS IS STILL OVER EASTERN COLORADO. NAM IS THE OUTLIER IN
BRINGING THIS EASTWARD MORE QUICKLY...PREFER THE GFS AND OTHER
MODELS WHICH HOLD THE HIGHER LEVEL OVER THE MOUNTAINS TODAY BUT
THEN SPREAD CONVECTION EASTWARD OVERNIGHT. EXPECT THE PLAINS TO
BE CAPPED...BUT SHOWERS AND STORMS OVER THE MOUNTAINS WILL SPREAD
EASTWARD IN THE LATE AFTERNOON AND EVENING. END RESULT IS JUST TO
SLOW EVERYTHING DOWN A FEW HOURS. CAPES ARE STILL PRETTY
LOW...300-600 J/KG SO I THINK FOR THE AFTERNOON STORMS WILL MAINLY
BE WEAK...SOME BRIEF HEAVY RAIN POSSIBLE WITH THE STRONGER CELLS.
WITH SOUTHERLY WINDS AT ALL LEVELS...EXPECT CELLS TO MOVE ALONG
WELL ENOUGH. SOME POTENTIAL FOR SOME SLOWING AS STORMS GET ONTO
THE PLAINS THIS EVENING DUE TO THE STRONGER LOW LEVEL WINDS
CAUSING SOUTHWARD DEVELOPMENT...BUT I DO NOT EXPECT THIS TO BE
STRONG ENOUGH FOR TRAINING OR STATIONARY STORMS. IN ADDITION THE
AVAILABLE MOISTURE IS NOT THAT GREAT ANYWAY. HIGHS ON THE PLAINS
MAY NEED TO BE SLIGHTLY WARMER IF THE CLOUDS ARE DELAYED...BUT
LEFT THEM ALONE SINCE THERE SEEMS A DECENT CHANCE OF GETTING SOME
CLOUDS SPREADING OFF THE MOUNTAINS BY MID AFTERNOON.
.LONG TERM...(FRIDAY THROUGH WEDNESDAY)
ISSUED AT 246 AM MDT THU MAY 29 2014
ON FRIDAY...A MOIST AND UNSTABLE AIRMASS WILL BE OVER THE REGION
WITH THE UPPER LEVEL RIDGE AXIS SHIFTED TO THE EAST. PRECIPITABLE
WATER VALUES ARE PROGGED TO BE AROUND 0.80 INCHES IN DENVER...WITH
CAPES AROUND 400 J/KG EARLY FRIDAY AFTN. TOWARDS AKRON...THE PW
VALUES CLIMB TO AROUND 1.1 INCHES WITH SFC BASED CAPES CLOSE TO
1500 J/KG. A FRONTAL BOUNDARY IS PROGGED TO SLIP INTO THE
NORTHEASTERN PLAINS IN THE AFTN. THE FRONT MAY ACT AS A TRIGGER
FOR THE DEVELOPMENT OF THE STORMS...BUT IF IT STABILIZES TOO FAST
BEHIND THE FRONT THE STORMS MAY NOT LAST VERY LONG OVER THE PLAINS
IN SPITE OF THE MUCH HIGHER CAPE. THERE IS SOME CIN OF AROUND -80
J/KG SO CAP COULD PREVENT DEEP CONVECTION BEHIND THE FRONT.
THE MAIN AREA OF CONCERN WILL BE WHERE THE FRONT SETTLES ALONG
THE FRONT RANGE. INCREASING LOW LEVEL MOISTURE FM THE EAST WILL
ELEVATE THE CAPE AND COULD ALSO PRODUCE ENOUGH SHALLOW UPSLOPE TO
FOCUS THE THUNDERSTORMS ALONG THE FRONT RANGE DURING THE LATE AFTN
AND EVENING HOURS. THIS SCENARIO COULD ELEVATE THE FLOOD
POTENTIAL...ESPECIALLY ALONG ALREADY SWOLLEN CREEKS AND STREAMS
EXACERBATED BY THE RUNOFF. THE STORM MOTION IS PROGGED TO BE QUITE
WEAK...SOUTHWEST AT AROUND 5 KTS.
FOR SATURDAY...A DRIER SOUTHWESTERLY FLOW ALOFT WILL DEVELOP
ACROSS THE REGION. PLENTY OF LOW LEVEL MOISTURE STILL AROUND
HOWEVER. BETTER SHEAR WITH SOME SORT OF DRYLINE LIKELY DEVELOPING
AS WELL. LOWER PW VALUES AND BETTER STORM MOTIONS WILL LESSEN THE
FLASH FLOOD THREAT BUT INCREASE THE SEVERE THUNDERSTORM POTENTIAL.
LARGE HAIL AND TSTM WINDS ALONG WITH A TORNADO THREAT AS WELL.
NAM12 SOUNDINGS YIELD CAPES AROUND 900 J/KG OVER THE URBAN
CORRIDOR WITH CLOSE TO 2000 J/KG OVER THE NORTHEAST PLAINS.
NOTHING HAS CHANGED IN THE GRIDS THE REST OF THE PERIOD. THE DRIER
PATTERN IS EXPECTED TO DEVELOP SUNDAY THROUGH TUESDAY...AHEAD OF
AN UPPER TROUGH WHICH WILL MOVE INTO NEVADA. SLGT CHC POPS OVER
THE MOUNTAINS EACH DAY...WITH A GREATER CHANCE OF STORMS POSSIBLY
DEVELOPING OVER THE FAR NORTHEAST PLAINS BY TUESDAY.
&&
.AVIATION...(FOR THE TAFS THROUGH 18Z FRIDAY MORNING)
ISSUED AT 1049 AM MDT THU MAY 29 2014
DENVER CYCLONE HAS BEEN SPINNING AROUND KDEN THIS MORNING KEEP THE
STRONGER SOUTHERLY WINDS JUST THE THE EAST. THIS WILL KEEP WIND
DIRECTIONS TRICKY...ESPECIALLY AT KDEN. ASSUMING ONCE TEMPERATURES
WARM MORE THE SOUTHEASTERLIES WILL BE ABLE TO PUSH IN A LITTLE
FARTHER WEST TO AFFECT AT LEAST KDEN AND KAPA. LOOKING FOR
CONVECTION TO BEGIN AFFECTING THE AIRPORTS AFTER 20Z.
OVERALL...VFR CONDITIONS SHOULD PREVAIL THROUGH TONIGHT. STORM
BASES WILL GENERALLY BE HIGH BUT INSTRUMENT APPROACHES MAY BE
NEEDED AT KDEN FOR A SHORT TIME IF THE STORMS ARE MORE ORGANIZED
THAN EXPECTED. THESE STORMS WILL BE GENERALLY SLOW MOVING AND WILL
HAVE THE CHANCE OF PRODUCING GUSTY OUTFLOW WINDS TO 30 KTS.
&&
.HYDROLOGY...
ISSUED AT 1053 AM MDT THU MAY 29 2014
REISSUED THE FLOOD WARNING FOR THE CACHE LA POUDRE RIVER AT GREELEY
DUE TO THE RIVER REMAINING HIGH FROM SNOWMELT...AND THE EXPECTED
RAIN OVER THE NEXT COUPLE DAYS. NO CHANGES TO THE OTHER ADVISORIES
IN EFFECT THIS MORNING. GENERALLY RISEN OVER THE LAST COUPLE OF DAYS
WITH THE WARMING.
IN GENERAL THE FLOWS ARE NOT EXPECTED TO PRODUCE MORE THAN MINOR
LOWLAND FLOODING UNLESS THERE IS SIGNIFICANT RAINFALL...UNLIKELY
TODAY BUT POSSIBLE THE NEXT COUPLE OF DAYS. GREATEST RISK IS THE
NORTH PLATTE RIVER NEAR THE WYOMING BORDER WHERE THE SNOWMELT IS
GREATEST...AND IN BOULDER AND LARIMER COUNTIES WHERE THE STREAMS
WILL BE FULL AND THERE WILL BE A HIGHER THREAT OF SIGNIFICANT
RAIN AS DESCRIBED BELOW.
FOR FRIDAY AND FRIDAY NIGHT...INCREASING MOISTURE AND INSTABILITY
IS EXPECTED...ESPECIALLY AFTER 21Z. A FRONTAL BOUNDARY IS PROGGED
TO PUSH ITSELF INTO THE FRONT RANGE...WHICH COULD HELP TO ANCHOR
THE DEVELOPMENT OF THUNDERSTORMS ALONG AND WEST OF THE FRONT. THIS
COUPLED THE STORM MOTIONS OF 5 KTS AND ONGOING RUNOFF COULD
INCREASE THE FLASH FLOOD THREAT. ON SATURDAY...THERE WILL BE SOME
DECREASE IN THE HEAVY RAIN THREAT WITH DRIER MID LEVEL AIR
INTRUDING FROM THE SOUTHWEST. THIS COUPLED WITH GREATER WEST TO
EAST STORM MOTION MAY ALSO HELP TO SHIFT THE FOCUS FOR THE STORMS
TO THE EAST OF THE FRONT RANGE. SOME OF THE STORMS HOWEVER COULD
BE SEVERE PRODUCING LARGE HAIL AND DAMAGING WINDS ESPECIALLY OVER
THE NORTHEAST PLAINS. THE HEAVY RAIN THREAT WILL STILL EXIST OVER
THE NORTHEAST PLAINS. SUNDAY THROUGH TUESDAY...THE THREAT OF
STORMS WILL BE EVEN LOWER WITH JUST A SLIGHT CHANCE OF
THUNDERSTORM EACH DAY. RUNOFF AT THAT TIME WILL BE PRIMARILY A
PRODUCT OF THE SNOWMELT.
&&
.BOU WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...KRIEDERMAN
SHORT TERM...GIMMESTAD
LONG TERM...COOPER
AVIATION...KRIEDERMAN
HYDROLOGY...COOPER/GIMMESTAD/KRIEDERMAN
AREA FORECAST DISCUSSION
NWS TAMPA BAY RUSKIN FL
340 PM EDT THU MAY 29 2014
.SYNOPSIS...
19Z WATER VAPOR AND H4 RAP ANALYSIS SHOWS A NORTHERN STREAM FLOW
ARRIVING OVER THE PACIFIC NORTHWEST AROUND THE BASE OF A SHARP
TROUGH AXIS BEFORE RIDGING BACK TO THE NORTH THROUGH SOUTH-CENTRAL
CANADA. THE FLOW THEN DROPS BACK TO THE SOUTHEAST THROUGH THE GREAT
LAKES AND THEN OFF THE NEW ENGLAND COAST. THE OTHER FEATURE OF NOTE
IS A CUT-OFF UPPER LOW STALLED NEAR THE BASE OF THE NORTHERN STREAM
RIDGE OVER THE SOUTHERN MS VALLEY. THIS FEATURE WILL NEVER REALLY
HAVE A SIGNIFICANT INFLUENCE ON OUR LOCAL WEATHER AS IT SPINS AND
PLACE AND SLOWLY FILLS DURING THE NEXT 24-48 HOURS.
29/12Z KTBW SOUNDING SHOWS A SEASONABLE PROFILE WITH A PW VALUES OF
JUST UNDER 1.5". MID-LEVEL TEMPS ARE A BIT ON THE COOL SIDE WITH A
MEASURED 500MB TEMP AROUND -11C. THIS IS ABOUT A DEGREE COOLER THAN
THE NAM/GFS FORECAST. A DEGREE DOES NOT SOUND LIKE MUCH...BUT CAN BE
ALL THE DIFFERENCE IN THE WORLD OF A RISING AIR PARCEL. EITHER
WAY...-11C IS ON THE COOL SIDE AND SHOULD HELP SUPPORT
AFTERNOON/EVENING STORM DEVELOPMENT...AT LEAST INITIALLY UNTIL
LATENT HEAT RELEASE FROM THE EARLY CONVECTION BEGINS TO CONTAMINATE
THE OVERALL COLUMN.
AT THE SURFACE...THE FL PENINSULA RESIDES ON THE WESTERN PERIPHERY
OF THE SUBTROPICAL RIDGE AXIS PROVIDING A GENERAL SOUTHEAST FLOW
PATTERN IN THE 1000-700MB LAYER. AS LONG AS THE COLUMN IS NOT TOO
DRY (WHICH IT IS NOT)...THEN THIS FLOW PATTERN TENDS TO BE WET ONE
IN TERMS OF STORMS COVERAGE THROUGH THE COURSE OF THE
AFTERNOON/EVENING.
&&
.SHORT TERM (REST OF TODAY THROUGH FRIDAY)...
AS WOULD BE EXPECTED WITH A MODERATE SE FLOW REGIME IN THE LOWER
LEVELS...THE EARLIER ACTIVITY HAS FORMED OVER THE SOUTHERN ZONES.
HAVE SEEN A FEW MORE FOCUSED STORMS OVER THE NATURE COAST...BUT THE
WIDESPREAD CONVECTION HAS BEEN DOWN TOWARD FORT MYERS AND PUNTA
GORDA. WOULD EXPECT THIS ACTIVITY TO "RIPPLE" NORTHWARD UP THE
SEA-BREEZE DURING THE NEXT SEVERAL HOURS INTO THE TAMPA BAY/I-4
CORRIDOR AND THEN EVEN FURTHER NORTHWARD WITH TIME. LOCAL HIRES
WRFARW RUNS AND LATEST HRRR CONTINUE TO SUGGEST MODERATE UPDRAFT
STRENGTH...INDICATIVE OF A FEW STRONGER STORMS...BUT GENERALLY NOT
WIDESPREAD SEVERE. CURRENT RAIN CHANCES THROUGH THE EARLY EVENING
CONTINUE TO INDICATE LIKELY WORDING UP ALONG THE I-75 CORRIDOR AND
SEE LITTLE REASON TO MAKE SIGNIFICANT CHANGES AT THIS TIME.
THIS FLOW REGIME USUALLY SEES THE EARLIER ENDING TO THE CONVECTION
OVER THE SOUTHERN ZONES WITH THE TAMPA BAY AREA AND NATURE COAST
HOLDING HIGHER RAIN CHANCES THROUGH 00-02 UTC. BY LATER THIS
EVENING...ALL AREAS SHOULD QUIET DOWN AND RESULT IN A GENERALLY DRY
OVERNIGHT PERIOD WITH SEASONABLE TEMPS.
A VERY SIMILAR SYNOPTIC PATTERN APPEARS TO BE IN PLACE FOR FRIDAY AS
WELL. 1000-700MB FLOW IS MODERATE (~10KNOTS) FROM THE
SOUTHEAST...AND WITH SIMILAR MOISTURE THROUGH THE COLUMN WITH SHOW
EARLY/MID AFTERNOON CONVECTION OVER THE SOUTHERN ZONES SPREADING
NORTH WITH TIME. THOSE WITH FRIDAY AFTERNOON/EVENING PLANS OUTDOORS
SHOULD BE PREPARED TO DEAL WITH AT LEAST A BRIEF PERIOD OF
RAIN/LIGHTNING. THE SYNOPTIC FLOW REGIME LOOKS TO FAVOR THE FLORIDA
WEST COAST SEA BREEZE FOR CONVECTIVE COVERAGE INTO THE UPCOMING
WEEKEND.
&&
.MID TERM (FRIDAY-SATURDAY)...
AN UPPER LEVEL RIDGE WILL BEGIN TO BUILD OVER THE SOUTHEASTERN
U.S. ON SATURDAY WITH A REINFORCING SURFACE HIGH BEGINNING TO SINK
SOUTHWARD FROM THE NORTH. EAST TO SOUTHEAST WINDS CONTINUE FOR
SATURDAY AFTERNOON...AND STILL EXPECTING A CHANCE FOR RAIN THROUGH
THE AFTERNOON AND EVENING HOURS WITH SEA BREEZE AND OUTFLOW BOUNDARY
INTERACTIONS. TEMPERATURES ARE EXPECTED TO BE NEAR NORMAL VALUES.
.LONG TERM (SATURDAY NIGHT-WEDNESDAY)...
THE UPPER-LEVEL HIGH WILL CONTINUE TO BUILD OVER THE REGION WITH
SURFACE HIGH PRESSURE RIDGING ACROSS THE AREA FROM THE NORTH FOR
THE START OF THE LONG TERM PERIOD. EASTERLY WINDS WILL REMAIN IN
PLACE FOR SATURDAY NIGHT INTO SUNDAY...WITH SCATTERED AFTERNOON
AND EVENING SHOWERS AND THUNDERSTORMS EXPECTED SUNDAY ALONG SEA
BREEZE AND OUTFLOW BOUNDARIES. THE SURFACE HIGH WILL DRIFT
SOUTHWARD EARLY NEXT WEEK...WITH MODELS SHOWING SOME DRIER AIR
WORKING SOUTHWARD AS WELL. BACKGROUND EASTERLY WINDS WILL CONTINUE
AND WILL STILL SHOW AT LEAST A SLIGHT CHANCE OF RAIN FOR MOST
AREAS EACH DAY...AND MORE OF A CHANCE FOR THE SOUTH WHERE THE
INFLUENCE OF DRIER AIR WILL BE LESS. TEMPERATURES WILL REMAIN NEAR
OR SLIGHTLY ABOVE NORMAL THROUGH THE PERIOD.
&&
.AVIATION...
SHOWERS AND STORMS ARE BEGINNING TO FILL IN THE AREA WITH SOUTHERN
TERMINALS OF KRSW TO KPGD ALREADY BEING AFFECTED. CONVECTIVE
COVERAGE FOR THESE AREAS SHOULD DIMINISH BY EARLY EVENING WHILE
STORMS WORK THEIR WAY NORTHWARD TO THE TAMPA BAY AREA TERMINALS.
WITHIN A FEW HOURS OF SUNSET THE ACTIVITY SHOULD DIMINISH AND RESULT
IN A QUIET OVERNIGHT PERIOD WITH MAINLY VFR CONDITIONS. MORE
AFTERNOON AND EVENING STORMS WILL FIRE UP ON FRIDAY WITH A GOOD
CHANCE TO SEE A STORM AT EACH TERMINAL.
&&
.MARINE...
HIGH PRESSURE IN THE ATLANTIC CONTINUES TO RIDGE OVER FLORIDA INTO
THE GULF WATERS PRODUCING SOUTHEAST WINDS IN THE 8 TO 12 KNOT RANGE.
WINDS ALONG THE COAST WILL VEER AROUND TO THE SOUTH SOUTHWEST EACH
AFTERNOON WITH THE ONSET OF THE SEA BREEZE. SEAS WILL REMAIN LESS
THAN 2 FEET THROUGH THE REMAINDER OF THE WEEK. THE MAIN MARINE
CONCERN WILL BE SCATTERED AFTERNOON AND EVENING THUNDERSTORMS
PRODUCING BRIEF GUSTY WINDS AND HIGHER SEAS.
&&
.FIRE WEATHER...
THE WEATHER PATTERN WILL NOT CHANGE MUCH OVER THE NEXT SEVERAL DAYS.
MOIST LOWER LEVELS WILL PREVENT RELATIVE HUMIDITY FROM REACHING
CRITICAL LEVELS...AND NO SIGNIFICANT FIRE WEATHER CONCERNS ARE
ANTICIPATED. EXPECT TYPICAL AFTERNOON STORMS TO DEVELOP EACH DAY
AS WELL...WITH RAIN CHANCES REMAINING AT OR ABOVE SEASONAL NORMALS
THROUGH THE WEEKEND.
FOG POTENTIAL...PATCHY GROUND FOG WILL BE POSSIBLE LATE EACH NIGHT
INTO THE EARLY MORNING HOURS EACH DAY.
&&
.PRELIMINARY POINT TEMPS/POPS...
TPA 75 88 74 88 / 50 50 40 50
FMY 72 91 72 91 / 30 70 20 50
GIF 72 89 71 89 / 30 40 30 50
SRQ 72 89 71 88 / 50 50 30 50
BKV 69 88 68 89 / 50 50 40 50
SPG 76 87 75 89 / 50 40 40 40
&&
.TBW WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
GULF WATERS...NONE.
&&
$$
SYNOPSIS/SHORT TERM/AVIATION/MARINE/FIRE WX...MROCZKA
MID TERM/LONG TERM...CARLISLE
AREA FORECAST DISCUSSION
NWS COLUMBIA SC
237 PM EDT THU MAY 29 2014
.SYNOPSIS...
A COLD FRONT WILL PUSH SOUTHWARD INTO THE NORTHERN PORTION OF
SOUTH CAROLINA THIS EVENING...AND THEN CONTINUE SLOWLY SOUTHWARD
INTO THE SOUTHERN PORTIONS OF THE AREA THROUGH FRIDAY NIGHT/EARLY
SATURDAY. THIS FRONT WILL STALL JUST SOUTH OF THE AREA
SUNDAY...WHILE DRIER AIR PUSHED INTO THE FORECAST AREA FROM THE
NORTH TO START OFF THE WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
THIS AFTERNOON...THE MAIN UPPER-LEVEL LOW WILL REMAIN IN THE
LOWER MISSISSIPPI RIVER VALLEY WITH A RIDGE AXIS OVER THE FORECAST
AREA. A SHORTWAVE TROUGH MAY BE CAUGHT IN THIS RIDGE. THE MAIN
SURFACE FRONT WILL BE NEAR THE NORTH PART OF THE FORECAST AREA
THIS AFTERNOON WITH CONVERGENCE OCCURRING AHEAD OF THE FRONT. THE
PATTERN SUPPORTS SCATTERED THUNDERSTORMS WITH COVERAGE LIMITED BY
SLOW MOVEMENT. THE HRRR INDICATES SCATTERED THROUGH THE AFTERNOON.
WE HAVE CONTINUED THE FORECAST OF CHANCE POPS OVER MOST AREAS.
EARLY AFTERNOON LAPS SOUNDINGS HAD PLENTY OF MOISTURE...WITH
PRECIPITABLE WATER VALUES ABOVE 1.7 OF AN INCH. THE SOUNDINGS
SHOWED STEEP LOW-LEVEL LAPSE RATES. HEAVY PRECIPITATION LOADING AND
THE LAPSE RATES INDICATE A POTENTIAL FOR STRONG GUSTY DOWNBURST
WINDS...WHILE THE MAIN WIND PATTERN REMAINS RELATIVELY WEAK
ASSOCIATED WITH THE UPPER RIDGING WHICH SUPPORTS SLOW STORM
MOVEMENT AND HEAVY RAIN. THE TEMPERATURE FORECAST IS ON TRACK
WITH HIGHS AROUND 90.
TONIGHT...CONVERGENCE ASSOCIATED WITH THE FRONT AND INTERACTING
OUTFLOW BOUNDARIES SUPPORT A CONTINUED CHANCE OF THUNDERSTORMS
TONIGHT. THE SPC AND CAE WRF INDICATE SIGNIFICANT COVERAGE MAINLY
IN THE NORTH PART OF THE FORECAST AREA THROUGH LATE TONIGHT.
HOWEVER...WE FORECASTED A LOWER POP LATE BECAUSE OF DIURNAL
COOLING AND PREVIOUS CONVECTIVE OVERTURNING. THE TEMPERATURE
GUIDANCE WAS CLOSE WITH LOWS IN THE UPPER 60S.
&&
.SHORT TERM /FRIDAY THROUGH SATURDAY NIGHT/...
UPPER LEVEL LOW WILL CONTINUE TO SLOWLY ERODE OVER THE WESTERN GULF
STATES WITH THE WEAK FRONT ACROSS THE CENTRAL ATLANTIC STATES EDGING
SOUTHWARD INTO THE AREA FRIDAY. THE FRONT THE SLOWLY TRACK THROUGH
THE THE NORTHERN MIDLANDS ON FRIDAY...BE STRETCHED ACROSS THE
CENTRAL MIDLANDS ON SATURDAY...FINALLY MOVING SOUTH OF THE AREA
EARLY SATURDAY NIGHT. WITH THE FRONT MOVING INTO THE AREA ON FRIDAY
AND INSTABILITY MODERATE EXPECT THUNDERSTORM COVERAGE TO THE THE
HIGHEST SO FAR THIS WEEK. SEVERE THUNDERSTORM CONCERN FOR FRIDAY
REMAINS LOW AS WET BULB ZERO HEIGHTS WILL BE AROUND 12 KFT AND
FREEZING LEVELS OVER 13 KFT...HOWEVER WITH PWAT VALUES BEING 1.7
INCHES OR GREATER ACROSS THE CENTRAL MIDLANDS AND CSRA DAMAGING
WINDS FROM PRECIPITATION LOADING WILL AGAIN BE POSSIBLE. LOCALIZED
HEAVY RAINFALL WILL ALSO BE POSSIBLE AS WINDS THROUGH THE COLUMN
WILL BE 20 KNOTS OR LESS.
ON SATURDAY PWAT VALUES WILL BE 1.5 INCHES OR GREATER THROUGH THE
CENTRAL MIDLANDS AND CSRA WITH DRIER AIR MOVING INTO THE NORTHERN
MIDLANDS. THIS WILL CREATE ANOTHER ROUND OF AFTERNOON AND EVENING
SHOWERS AND THUNDERSTORMS WITH HIGHEST CHANCES OF CONVECTION ACROSS
THE CSRA WHERE CONVERGENCE AHEAD OF THE FRONT WILL BE
STRONGEST...WHILE DRIER AIR ENTERING THE NORTHERN MIDLANDS WILL HELP
SUPPRESS CONVECTION. THE POTENTIAL FOR SEVERE THUNDERSTORMS WILL
AGAIN BE LOW...HOWEVER WITH WEAK WINDS ALOFT PERSISTING AND
RESULTING IN SLOW MOVING CELLS THE POTENTIAL FOR LOCALIZED HEAVY
RAINFALL WILL CONTINUE.
TEMPERATURES WILL BE IN THE MIDDLE TO UPPER 80S FOR AFTERNOON HIGHS
WITH OVERNIGHT LOWS IN THE MIDDLE TO UPPER 60S.
&&
.LONG TERM /SUNDAY THROUGH THURSDAY/...
MODELS ARE IN GOOD AGREEMENT AND HAVE BEEN CONSISTENT OVER THE PAST
SEVERAL RUNS FOR THE LONG TERM. UPPER LEVEL RIDGING WILL BE OVER THE
REGION THROUGH MONDAY WITH THE UPPER LEVEL PATTERN BECOMING MORE
ZONAL FOR TUESDAY ONWARD. THE FRONT MOVE JUST SOUTH OF THE AREA
SUNDAY AND STALL AS HIGH PRESSURE JUST OFFSHORE OF NC TAKES CONTROL
OF THE AREA. THIS WILL KEEP DRIER AIR OVER THE FORECAST AREA FOR
SUNDAY AND MONDAY WITH MOISTURE RETURNING TO THE AREA MONDAY NIGHT
AS THE NEXT COLD FRONT TRACKS TOWARD THE AREA FROM THE WEST. THIS
WILL BRING CHANCES OF SHOWERS AND THUNDERSTORMS BACK INTO THE
FORECAST FOR TUESDAY AND WEDNESDAY. TEMPERATURES THROUGH THE LONG
TERM WILL BE NEAR NORMAL.
&&
.AVIATION /19Z THURSDAY THROUGH TUESDAY/...
A COLD FRONT APPROACHING FROM THE NORTH WILL BE IN THE AREA
TONIGHT. CONVERGENCE ASSOCIATED WITH THE FRONT WILL SUPPORT
THUNDERSTORMS BUT COVERAGE WILL BE LIMITED BECAUSE OF UPPER-LEVEL
RIDGING AND SLOW STORM MOVEMENT. HIGH PRECIPITABLE WATER AND
PRECIPITATION LOADING PLUS STEEP LOW-LEVEL LAPSE RATES MAY SUPPORT
STRONG GUSTY WINDS NEAR ANY THUNDERSTORMS. THE HIGH RESOLUTION
MODELS SUPPORT SCATTERED COVERAGE. THE GREATEST COVERAGE WILL
LIKELY BE NEAR MAXIMUM HEATING. CONVERGENCE ASSOCIATED WITH THE
FRONT WILL SUPPORT A CONTINUED CHANCE THROUGH TONIGHT. HIGH LOW-
LEVEL MOISTURE MAY LEAD TO STATUS AND FOG DURING THE EARLY MORNING
HOURS. THE GFS MOS AND LAMP PLUS NAM MOS WERE CONSISTENT
INDICATING IFR OR MVFR FOG AT THE RIVER VALLEY TERMINALS OF AGS
AND DNL.
EXTENDED AVIATION OUTLOOK...MOISTURE ASSOCIATED WITH THE REMNANTS
OF A STALLED FRONT WILL CONTINUE DURING MUCH OF THE OUTLOOK
PERIOD. EXPECT RESTRICTIONS AT TIMES MAINLY FROM AFTERNOON AND
EVENING THUNDERSTORMS AND EARLY MORNING STRATUS AND FOG.
&&
.CAE WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
GA...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS COLUMBIA SC
142 PM EDT THU MAY 29 2014
.SYNOPSIS...
A COLD FRONT WILL PUSH SOUTHWARD INTO THE NORTHERN PORTION OF
SOUTH CAROLINA THIS EVENING...AND THEN CONTINUE SLOWLY SOUTHWARD
INTO THE SOUTHERN PORTIONS OF THE AREA THROUGH FRIDAY NIGHT/EARLY
SATURDAY. THIS FRONT WILL STALL JUST SOUTH OF THE AREA
SUNDAY...WHILE DRIER AIR PUSHED INTO THE FORECAST AREA FROM THE
NORTH TO START OFF THE WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
THIS AFTERNOON...THE MAIN UPPER-LEVEL LOW WILL REMAIN IN THE
LOWER MISSISSIPPI RIVER VALLEY WITH A RIDGE AXIS OVER THE FORECAST
AREA. A SHORTWAVE TROUGH MAY BE CAUGHT IN THIS RIDGE. THE MAIN
SURFACE FRONT WILL BE NEAR THE NORTH PART OF THE FORECAST AREA
THIS AFTERNOON WITH CONVERGENCE OCCURRING AHEAD OF THE FRONT. THE
PATTERN SUPPORTS SCATTERED THUNDERSTORMS WITH COVERAGE LIMITED BY
SLOW MOVEMENT. THE HRRR INDICATES SCATTERED THROUGH THE AFTERNOON.
WE HAVE CONTINUED THE FORECAST OF CHANCE POPS OVER MOST AREAS.
EARLY AFTERNOON LAPS SOUNDINGS HAD PLENTY OF MOISTURE...WITH
PRECIPITABLE WATER VALUES ABOVE 1.7 OF AN INCH. THE SOUNDINGS
SHOWED STEEP LOW-LEVEL LAPSE RATES. HEAVY PRECIPITATION LOADING AND
THE LAPSE RATES INDICATE A POTENTIAL FOR STRONG GUSTY DOWNBURST
WINDS...WHILE THE MAIN WIND PATTERN REMAINS RELATIVELY WEAK
ASSOCIATED WITH THE UPPER RIDGING WHICH SUPPORTS SLOW STORM
MOVEMENT AND HEAVY RAIN. THE TEMPERATURE FORECAST IS ON TRACK
WITH HIGHS AROUND 90.
TONIGHT...CONVERGENCE ASSOCIATED WITH THE FRONT AND INTERACTING
OUTFLOW BOUNDARIES SUPPORT A CONTINUED CHANCE OF THUNDERSTORMS
TONIGHT. THE SPC AND CAE WRF INDICATE SIGNIFICANT COVERAGE MAINLY
IN THE NORTH PART OF THE FORECAST AREA THROUGH LATE TONIGHT.
HOWEVER...WE FORECASTED A LOWER POP LATE BECAUSE OF DIURNAL
COOLING AND PREVIOUS CONVECTIVE OVERTURNING. THE TEMPERATURE
GUIDANCE WAS CLOSE WITH LOWS IN THE UPPER 60S.
&&
.SHORT TERM /FRIDAY THROUGH SATURDAY NIGHT/...
UPPER LEVEL LOW ACROSS THE WESTERN GULF STATES WILL REMAIN QUASI-
STATIONARY THROUGH FRIDAY NIGHT WITH THE UPPER LEVEL TROUGH JUST
OFFSHORE OF THE EAST COAST DIGS SOUTHWARD. FRONTAL BOUNDARY WILL
CONTINUE SLOWLY PUSHING INTO THE SOUTHERN CWA THROUGH
FRIDAY...BEFORE STALLING OUT IN THE SOUTH FRIDAY NIGHT INTO
SATURDAY MORNING. THE PROXIMITY TO THE FRONT WILL ALLOW FOR A
CONTINUATION OF ISOLATED TO SCATTERED SHOWERS AND THUNDERSTORMS
INTO SATURDAY. AFTERNOON TEMPERATURES WILL BE IN THE MID TO UPPER
80S BOTH DAYS...WHILE LOWS WILL FALL INTO THE MIDDLE TO UPPER 60S.
&&
.LONG TERM /SUNDAY THROUGH WEDNESDAY/...
MODELS ARE IN GOOD AGREEMENT THROUGH THE LONG TERM. THE CENTER OF
AN UPPER LEVEL RIDGE THAT HAD BEEN ACROSS THE UPPER MID-WEST WILL
SLIDE SOUTHEASTWARD...SETTLING OVER THE SOUTHEASTERN UNITED STATES
BY SUNDAY. STRONG UPPER LOW WILL SPIN WELL OFF THE MID-ATLANTIC
COAST. SURFACE HIGH PRESSURE AND SLIGHTLY DRIER AIR WILL
DOMINATE INTO THE EARLY PART OF THE WEEK. MOISTURE BEGINS TO
RETURN TO THE AREA ON TUESDAY INTO WEDNESDAY. TEMPERATURES THROUGH THE
LONG TERM WILL BE NEAR TO SLIGHTLY BELOW NORMAL.
&&
.AVIATION /18Z THURSDAY THROUGH TUESDAY/...
A COLD FRONT APPROACHING FROM THE NORTH WILL BE IN THE AREA
TONIGHT. CONVERGENCE ASSOCIATED WITH THE FRONT WILL SUPPORT
THUNDERSTORMS BUT COVERAGE WILL BE LIMITED BECAUSE OF UPPER-LEVEL
RIDGING AND SLOW STORM MOVEMENT. HIGH PRECIPITABLE WATER AND
PRECIPITATION LOADING PLUS STEEP LOW-LEVEL LAPSE RATES MAY SUPPORT
STRONG GUSTY WINDS NEAR ANY THUNDERSTORMS. THE HIGH RESOLUTION
MODELS SUPPORT SCATTERED COVERAGE. THE GREATEST COVERAGE WILL
LIKELY BE NEAR MAXIMUM HEATING. CONVERGENCE ASSOCIATED WITH THE
FRONT WILL SUPPORT A CONTINUED CHANCE THROUGH TONIGHT. HIGH LOW-
LEVEL MOISTURE MAY LEAD TO STATUS AND FOG DURING THE EARLY MORNING
HOURS. THE GFS MOS AND LAMP PLUS NAM MOS WERE CONSISTENT
INDICATING IFR OR MVFR FOG AT THE RIVER VALLEY TERMINALS OF AGS
AND DNL.
EXTENDED AVIATION OUTLOOK...MOISTURE ASSOCIATED WITH THE REMNANTS
OF A STALLED FRONT WILL CONTINUE DURING MUCH OF THE OUTLOOK
PERIOD. EXPECT RESTRICTIONS AT TIMES MAINLY FROM AFTERNOON AND
EVENING THUNDERSTORMS AND EARLY MORNING STRATUS AND FOG.
&&
.CAE WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
GA...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
106 PM CDT THU MAY 29 2014
.DISCUSSION...
1131 AM CDT
MORNING UPDATE...
MADE SOME MINOR TWEAKS TO GOING FORECAST...MAINLY TO ADJUST SKY
TRENDS FOR EROSION OF STUBBORN LOW STRATUS OVER SOUTH AND
SOUTHWEST CWA AND TO RAISE TEMPERATURES A FEW DEGREES IN SOME
AREAS. DESPITE CWA BEING ON "COOL" SIDE OF STATIONARY FRONTAL
BOUNDARY DRAPPED ACROSS CENTRAL ILLINOIS...AIR MASS IS STILL QUITE
WARM AWAY FROM LAKE MICHIGAN INFLUENCE...WITH +14C AND +15C
RESPECTIVELY ON 12Z DVN AND ILX RAOBS AT 850 MB. SOUNDINGS DON`T
SHOW MIXING QUITE TO THIS LEVEL...BUT DRY ADIABATING MIXING TO 900
MB SHOULD YIELD LOW 80S MOST PLACES AWAY FROM THE LAKE AND SOME
MID 80S FAR SOUTH WHERE IT IS ALREADY 80 AS OF 11AM AT TIP.
ALONG IMMEDIATE LAKESHORE...MAINTAINED GOING HIGHS. NOT EXPECTING
STRATUS TO SURGE INLAND LIKE LATE YESTERDAY...BUT ENHANCED LAKE
COOLING SHOULD PUSH INLAND LATER TODAY.
OTHER CONCERN IS FOR THUNDERSTORMS IN THE SOUTHERN
CWA JUST TO THE NORTH OF STALLED BOUNDARY. DEWPOINTS HAVE
REMAINED WELL INTO THE 60S AND MODIFYING THE MORNING ILX SOUNDING
FOR CURRENT CONDITIONS OUTSIDE THE STRATUS DECK RESULTS IN VERY
LITTLE IF ANY CAP REMAINING. GIVEN PRESENCE OF REMNANT SHORTWAVE
FROM YESTERDAY AND STATIONARY BOUNDARY...AND POSSIBLE INFLUENCE
OF DIFFERENTIAL HEATING AS LOW CLOUDS ERODE...COVERAGE COULD BE A
BIT HIGHER THAN 20 POPS INDICATED IN GRIDS IN FAR SOUTHERN CWA.
FOR NOW...HAVE MAINTAINED GOING POPS AS CONVECTION HAS STARTED TO
FIRE IN AGITATED CU FIELD TO THE SOUTH IN THE ILX CWA. WILL
CONTINUE TO MONITOR TRENDS. IF CONVECTION DOES BECOME MORE
WIDESPREAD IN OUR FAR SOUTHERN COUNTIES...SIMILAR TO THE PAST FEW
DAYS...THE MAIN THREAT WILL BE HEAVY RAIN DUE TO VERY SLOW STORM
MOTIONS.
RC
//PREV DISCUSSION...
346 AM CDT
FORECAST CONCERNS THIS MORNING FOCUS ON DRIER NORTHEAST LOW LEVEL
WINDS TODAY...WITH DECREASING CLOUDINESS AND THREAT OF AFTERNOON
THUNDERSTORMS SHIFTING DOWNSTATE ALONG/SOUTH OF WFO LOT/ILX BORDER.
DRY AND MILD CONDITIONS ANTICIPATED OVER THE NEXT FEW DAYS WITH A
WARMING TREND INTO THE WEEKEND...AND A GRADUAL DECREASE IN LAKE
COOLING. A PERIOD OF ACTIVE WEATHER WITH HEAVY RAINFALL AND
INCREASING SEVERE THUNDERSTORM POTENTIAL APPEARS TO BE SHAPING UP
FOR DAYS 4-7 (SUNDAY-NEXT WEDNESDAY)...AS A COLD FRONT SAGS INTO
WARM/HUMID AIR MASS WHICH TAKES UP RESIDENCE ACROSS THE AREA.
WEAK SURFACE LOW PRESSURE CONTINUES TO SETTLE SOUTHWARD ACROSS
EASTERN MISSOURI THIS MORNING...WITH A NEARLY STATIONARY COLD FRONT
STRETCHING WEST-EAST ACROSS SOUTH CENTRAL IL/IN. THIS BOUNDARY WILL
CONTINUE TO BE THE FOCUS FOR DIURNAL SHOWER/THUNDERSTORM DEVELOPMENT
THIS AFTERNOON...AS WEAKENING SHEARED MID-LEVEL VORT MAXIMA
CONTINUES TO DRIFT SOUTH WHILE GETTING PULLED INTO CIRCULATION
AROUND CLOSED UPPER LOW OVER THE LOWER MISSISSIPPI VALLEY. VARIOUS
HIGH-RES CONVECTIVE-ALLOWING GUIDANCE DEPICTS AFTERNOON CONVECTION
DEVELOPING GENERALLY ALONG/SOUTH OF OUR SOUTHERN CWA BORDER...THUS
HAVE MAINTAINED SOME SLIGHT CHANCE POPS SOUTH OF ABOUT A FAIRBURY TO
WATSEKA TO FOWLER LINE. FARTHER NORTH...NORTHEAST LOW LEVEL WINDS
CONTINUE TO BRING DRIER AND MORE STABLE AIR INTO THE AREA FROM
ACROSS THE LAKES. PATCHY LOW CLOUD COVER OVER PARTS OF THE AREA
SHOULD CLEAR OUT LATER THIS MORNING...WITH MODEL FORECAST SOUNDINGS
INDICATING WARMING AND DRYING FROM ABOVE AS SUBSIDENCE DEVELOPS WITH
UPPER RIDGE BUILDING INTO THE UPPER MIDWEST. THIS UPPER RIDGE
CONTINUES TO BUILD AND SLOWLY DRIFT SOUTHEAST ACROSS THE REGION INTO
SATURDAY...PRODUCING DRY CONDITIONS WITH A STEADY MODERATION IN
TEMPERATURES. SURFACE HIGH PRESSURE WILL REMAIN TO OUR NORTHEAST AND
EAST DURING THE PERIOD...GRADUALLY WEAKENING AND PULLING OFF TO THE
EAST AND ALLOWING NORTHEAST SURFACE WINDS TO GRADUALLY VEER
SOUTHEAST AND DECREASING THE AMOUNT OF LAKE COOLING. WITH A GOOD
AMOUNT OF SUNSHINE EXPECTED TODAY...FRIDAY AND SATURDAY...HAVE
GENERALLY UTILIZED WARMER GUIDANCE FOR HIGH TEMPS...WITH UPPER 70S
AND LOWER 80S EXPECTED TODAY WELL AWAY FROM THE LAKE WARMING TO THE
LOW-MID 80S BY SATURDAY. AS FETCH ACROSS THE LAKE DECREASES WITH
VEERING LOW LEVEL WINDS...SHORE AREAS SHOULD ALSO MODERATE FROM THE
LOW-MID 60S TODAY TO THE LOW-MID 70S BY SATURDAY. DRY AIR WILL
SUPPORT COOL OVERNIGHT TEMPS PARTICULARLY ACROSS NORTHEAST IL...WITH
A FEW UPPER 40S POSSIBLE TONIGHT NEAR THE LAKE.
ON SATURDAY...THE UPPER RIDGE AXIS WILL SHIFT SOUTHEAST OF THE AREA
AS A STRONG UPPER JET MAX SPREADS ACROSS ONTARIO AND THE FAR UPPER
MIDWEST. MEDIUM RANGE MODEL SOLUTIONS ARE IN GOOD AGREEMENT IN
DEPICTING A SHORT WAVE LIFTING FROM THE PLAINS TOWARD THE UPPER
MISSISSIPPI VALLEY SATURDAY AFTERNOON/NIGHT...HELPING INDUCE SURFACE
PRESSURE FALLS ACROSS THE UPPER MISSISSIPPI VALLEY AND VEERING LOW
LEVEL WINDS MORE SOUTHERLY. WARM/MOIST ADVECTION IN RETURN FLOW WILL
BRING WARM AND HUMID CONDITIONS BACK TO THE FORECAST AREA BY
SUNDAY...WITH THE POTENTIAL FOR A FEW ELEVATED THUNDERSTORMS ACROSS
NORTHWEST IL TOWARD SUNDAY MORNING ALONG EASTERN PERIPHERY OF BROAD
SOUTHWESTERLY LOW LEVEL JET AND THE SUBTLE WARM FRONT. POTENTIAL FOR
THUNDERSTORMS INCREASES AS AREA BECOMES FIRMLY ENTRENCHED IN THE
WARM SECTOR SUNDAY AND SUNDAY NIGHT...WITH TEMPS MID-UPPER 80S AND
DEW POINT TEMPS 65-70 PROGGED.
GUIDANCE DIFFERS WITH DETAILS OF SHORT WAVES MOVING THROUGH
SOUTHWEST FLOW ALOFT INTO EARLY NEXT WEEK...THOUGH THE POTENTIAL
EXISTS FOR SEVERAL ROUNDS OF THUNDERSTORMS TO AFFECT THE REGION INTO
AT LEAST TUESDAY AS COLD FRONT SLOWLY MOVES SOUTH INTO A VERY WARM
AND MOIST AIR MASS. WEST-SOUTHWEST TO EAST-NORTHEAST ORIENTATION OF
BOUNDARY COMBINED WITH HIGH PRECIPITABLE WATER VALUES (1.5-2.0
INCHES PER GFS SOUNDINGS) WILL LIKELY SUPPORT A HEAVY RAINFALL
THREAT...AND INCREASING DEEP LAYER BULK SHEAR ESPECIALLY MON-WED
ALSO SUGGESTS SEVERE MCS POTENTIAL. FOR NOW HAVE MAINTAINED RATHER
BROAD-BRUSHED CHANCE POPS FROM SUNDAY ONWARD...THOUGH DETAILS SUCH
AS THE LOCATION OF THE FRONTAL BOUNDARY (LIKELY MODULATED BY
CONVECTIVE OUTFLOWS)...AS WELL AS INDIVIDUAL LOW-AMPLITUDE WAVES
WILL ULTIMATELY DRIVE CONVECTIVE TRENDS AND TIMING DURING THIS
PERIOD.
RATZER
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 18Z...
* NELY-ELY WINDS ARND 10KT OR SLIGHTLY HIGHER THROUGH SUNSET.
KREIN
//DISCUSSION...UPDATED 18Z...
THE LOW STRATUS BURNED OFF BY LATE MORNING AND VFR CONDITIONS ARE
EXPECTED TO PREVAIL FOR THE REMAINDER OF THE DAY AND INTO TONIGHT.
THE MAIN FORECAST CONCERN WILL BE WIND DIRECTION. WITH HIGH
PRESSURE OVER THE UPPER GREAT LAKES AND COMPLEX TROUGHING OVER THE
CENTRAL PLAINS...WINDS WILL BE ELY OR ENEY THROUGH THE PERIOD WITH
SPEEDS NEAR OR SLIGHTLY GREATER THAN 10KT. WITH WEAK WINDS
ALOFT...DO NOT EXPECT MUCH IN THE WAY OF GUSTINESS...THOUGH AN
OCCASIONAL GUST TO 15KT IS POSSIBLE. UNDER CLEAR SKIES...EXPECT
THE LOW LEVELS TO DECOUPLE AT SUNSET AND WINDS SHOULD DROP OFF TO
AROUND 5KT OR LESS. WITH HIGH PRESSURE CONTINUING TO BUILD SOUTH
ACROSS THE WESTERN GREAT LAKES REGION AND INTO THE MIDDLE
MISSISSIPPI VALLEY...EXPECT GENERALLY LIGHT WINDS AND MOSTLY CLEAR
SKIES TO PREVAIL THROUGH THE PERIOD. THERE IS SOME CONCERN FOR
SOME ISOLD BR DEVELOPMENT DURG THE PRE-DAWN HOURS...BUT ANY VIS
RESTRICTIONS WOULD LIKELY BE AT RFD/DPA RATHER THAN THE MORE URBAN
SITES.
KREIN
//ORD AND MDW CONFIDENCE...UPDATED 18Z...
* HIGH CONFIDENCE IN ALL FORECAST ELEMENTS.
KREIN
//OUTLOOK FOR ORD/MDW FOR 00Z SATURDAY-12Z THURSDAY...UPDATED 12Z...
FRIDAY NIGHT THROUGH SATURDAY...VFR.
SUNDAY THROUGH WEDNESDAY...PERIODIC CHANCES FOR THUNDERSTORMS.
PRIMARILY VFR.
BMD
&&
.MARINE...
246 AM CDT
HIGH PRESSURE EXTENDS FROM HUDSON BAY INTO THE CENTRAL GREAT LAKES
REGION WHERE IT WILL SLOWLY MIGRATE TO THE EASTERN LAKES BY
SATURDAY. IN THE MEANTIME...MODEST NORTHEAST TO EAST WINDS WILL
PREVAIL ACROSS LAKE MICHIGAN. WINDS ARE EXPECTED TO BE STRONGEST ON
THE SOUTH END OF THE LAKE WHERE IT MAY PEAK AROUND 15 TO 20 KT THIS
AFTERNOON. A WARM FRONT WILL LIFT ACROSS LAKE MICHIGAN THIS WEEKEND
WITH WINDS VEERING AROUND TO THE SOUTH BY SUNDAY. SOUTH TO SOUTHWEST
WINDS ARE THEN EXPECTED TO PERSIST THROUGH AROUND MIDWEEK WITH
ANOTHER COLD FRONT DROPS ACROSS THE LAKE.
BMD
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...NONE.
&&
$$
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Area Forecast Discussion
National Weather Service Lincoln IL
1215 PM CDT Thu May 29 2014
.DISCUSSION...
ISSUED 1036 AM CDT Thu May 29 2014
Back-door cool front has slipped south to just north of the I-70
corridor. True push of cool/dry air lags well north of the front,
though northeast flow north of the boundary has brought slightly
cooler and less humid air into the far northern CWA with dewpoints
in the low 60s, while upper 60s dewpoints remain over the central
and south. Aloft, water vapor imagery indicates a cutoff low
spinning through the lower MS valley with the northern fringes of
this feature bringing clouds into the southern CWA and lift
producing showers in far southern IL/IN. A separate weak shortwave
was noted in NW IL and is forecast to get absorbed into the
circulation of the upper low as is shifts SE today. 12Z ILX
sounding shows little airmass change from yesterday even as the
front has shifted south. Given afternoon CAPEs near 2000 J/kg and
light wind fields aloft, expect isolated to scattered thunderstorm
development as convective temperatures are reached. Hi-res models
show this possible for much of the CWA except the far north where
somewhat drier air should keep areas north of Peoria and Galesburg
dry. For the bulk of the CWA, slow moving iso/sct storms will
produce brief heavy rain rates. Given high instability and weak
shear with a boundary in the area, isolated land spouts will again
be a concern. Non-supercell tor parameters off RAP and NAM
suggest the central/southern CWA will again be at risk during
early to mid afternoon, especially near the main synoptic boundary or
mesoscale boundary interactions. Raised max temps a degree or two
with highs in the lower 80s.
&&
.AVIATION...
ISSUED 1215 PM CDT Thu May 29 2014
A weak cool front has slipped south of the I-72 terminals this
morning. Calm winds in the vicinity of the boundary become
ENE at 5-10 kts north of the boundary. This general wind flow is
expected through this TAF cycle as the front slowly shifts farther
south, and high pressure remains perched over the Great Lakes.
Isolated to scattered instability showers/storms have already
developed and will continue through late afternoon, despite the
front being to our south. Due to low coverage, have VCTS in TAFs and
will amend for tempo groups if conditions warrant. Brief reductions
to IFR cigs/vsbys possible in +TSRA. Diurnal decrease in activity
this evening with VFR conditions predominant through Thu morning.
Exception would be within a few hours of sunrise, with patchy MVFR
fog possible due to light winds and high RH.
25
&&
.PREV DISCUSSION...
ISSUED 250 AM CDT Thu May 29 2014
Weak frontal boundary centered just north of the I-70 corridor
early this morning. High pressure over the Great Lakes is
providing a northeast flow behind the front, which has dropped dew
points into the 50s from Galesburg to Bloomington northward, while
mid to upper 60s still prevail elsewhere. Still a fair amount of
cloud cover over the forecast area, some streaming north from the
ever-present upper low, now centered in south central Arkansas.
There were a few showers recently near the boundary which drifted
northwest due to that low, although these have now faded out.
Rain chances continue to be the primary forecast concern, with
next week`s chances a bit more challenging due to more model
disagreement.
SHORT TERM...Today through Saturday:
The frontal boundary should be quasi-stationary between the I-72
and I-70 corridors today, and will be the focus for the next round
of scattered showers and storms beginning around noon. Have had
some heavier pockets of rain recently, and with precipitable water
values around 1.5 to 1.6 inches, today shouldn`t be any different.
Severe weather threat remains minimal due to low shear values, but
cannot rule out some isolated funnels or land spouts similar to
yesterday, with the boundary overhead. Non-supercell tornado
parameter from the RAP model focuses on a couple areas, one along
the I-74 corridor just north of the main precipitation area, and
the other along I-72 near the boundary. Any such activity would be
most likely between noon and 4 pm.
The boundary will be pushed southward again tonight as an upper
high slides moves into the upper Mississippi Valley. As it will
not make it terribly far, the convection on Friday and Saturday will
be close by, but mostly out of our forecast area. Have maintained
some 20% PoP`s along the southern CWA border Friday afternoon, but
kept Saturday dry for now.
LONG TERM...Sunday through Wednesday:
Upper ridging breaks down during the weekend with more of a
southwest flow across the nation early next week, and the northern
jet stream along the Canadian border. Right now the ECMWF is the
odd model out in developing an upper low over the upper
Mississippi Valley which slowly drifts eastward through the Great
Lakes during the week, while the GFS, GEM and GFS ensembles have
more of periodic shortwave interaction between the two upper flows.
Sunday into early Monday are in most agreement with rain chances,
but trends widen after that. The ECMWF and the GEM to an extent
have the surface cyclone somewhat in agreement into Tuesday with
the cold front coming through, which would support the rain
chances continuing. Toward mid week, there is much more
uncertainty as the GFS never actually brings the front through and
holds it up near I-80, thus lingering rain chances, while the
ECMWF is dry. Have kept some PoP`s in for Wednesday for now, but
scaled them back from the initial blended guidance.
Geelhart
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
1103 AM CDT THU MAY 29 2014
.DISCUSSION...
346 AM CDT
FORECAST CONCERNS THIS MORNING FOCUS ON DRIER NORTHEAST LOW LEVEL
WINDS TODAY...WITH DECREASING CLOUDINESS AND THREAT OF AFTERNOON
THUNDERSTORMS SHIFTING DOWNSTATE ALONG/SOUTH OF WFO LOT/ILX BORDER.
DRY AND MILD CONDITIONS ANTICIPATED OVER THE NEXT FEW DAYS WITH A
WARMING TREND INTO THE WEEKEND...AND A GRADUAL DECREASE IN LAKE
COOLING. A PERIOD OF ACTIVE WEATHER WITH HEAVY RAINFALL AND
INCREASING SEVERE THUNDERSTORM POTENTIAL APPEARS TO BE SHAPING UP
FOR DAYS 4-7 (SUNDAY-NEXT WEDNESDAY)...AS A COLD FRONT SAGS INTO
WARM/HUMID AIR MASS WHICH TAKES UP RESIDENCE ACROSS THE AREA.
WEAK SURFACE LOW PRESSURE CONTINUES TO SETTLE SOUTHWARD ACROSS
EASTERN MISSOURI THIS MORNING...WITH A NEARLY STATIONARY COLD FRONT
STRETCHING WEST-EAST ACROSS SOUTH CENTRAL IL/IN. THIS BOUNDARY WILL
CONTINUE TO BE THE FOCUS FOR DIURNAL SHOWER/THUNDERSTORM DEVELOPMENT
THIS AFTERNOON...AS WEAKENING SHEARED MID-LEVEL VORT MAXIMA
CONTINUES TO DRIFT SOUTH WHILE GETTING PULLED INTO CIRCULATION
AROUND CLOSED UPPER LOW OVER THE LOWER MISSISSIPPI VALLEY. VARIOUS
HIGH-RES CONVECTIVE-ALLOWING GUIDANCE DEPICTS AFTERNOON CONVECTION
DEVELOPING GENERALLY ALONG/SOUTH OF OUR SOUTHERN CWA BORDER...THUS
HAVE MAINTAINED SOME SLIGHT CHANCE POPS SOUTH OF ABOUT A FAIRBURY TO
WATSEKA TO FOWLER LINE. FARTHER NORTH...NORTHEAST LOW LEVEL WINDS
CONTINUE TO BRING DRIER AND MORE STABLE AIR INTO THE AREA FROM
ACROSS THE LAKES. PATCHY LOW CLOUD COVER OVER PARTS OF THE AREA
SHOULD CLEAR OUT LATER THIS MORNING...WITH MODEL FORECAST SOUNDINGS
INDICATING WARMING AND DRYING FROM ABOVE AS SUBSIDENCE DEVELOPS WITH
UPPER RIDGE BUILDING INTO THE UPPER MIDWEST. THIS UPPER RIDGE
CONTINUES TO BUILD AND SLOWLY DRIFT SOUTHEAST ACROSS THE REGION INTO
SATURDAY...PRODUCING DRY CONDITIONS WITH A STEADY MODERATION IN
TEMPERATURES. SURFACE HIGH PRESSURE WILL REMAIN TO OUR NORTHEAST AND
EAST DURING THE PERIOD...GRADUALLY WEAKENING AND PULLING OFF TO THE
EAST AND ALLOWING NORTHEAST SURFACE WINDS TO GRADUALLY VEER
SOUTHEAST AND DECREASING THE AMOUNT OF LAKE COOLING. WITH A GOOD
AMOUNT OF SUNSHINE EXPECTED TODAY...FRIDAY AND SATURDAY...HAVE
GENERALLY UTILIZED WARMER GUIDANCE FOR HIGH TEMPS...WITH UPPER 70S
AND LOWER 80S EXPECTED TODAY WELL AWAY FROM THE LAKE WARMING TO THE
LOW-MID 80S BY SATURDAY. AS FETCH ACROSS THE LAKE DECREASES WITH
VEERING LOW LEVEL WINDS...SHORE AREAS SHOULD ALSO MODERATE FROM THE
LOW-MID 60S TODAY TO THE LOW-MID 70S BY SATURDAY. DRY AIR WILL
SUPPORT COOL OVERNIGHT TEMPS PARTICULARLY ACROSS NORTHEAST IL...WITH
A FEW UPPER 40S POSSIBLE TONIGHT NEAR THE LAKE.
ON SATURDAY...THE UPPER RIDGE AXIS WILL SHIFT SOUTHEAST OF THE AREA
AS A STRONG UPPER JET MAX SPREADS ACROSS ONTARIO AND THE FAR UPPER
MIDWEST. MEDIUM RANGE MODEL SOLUTIONS ARE IN GOOD AGREEMENT IN
DEPICTING A SHORT WAVE LIFTING FROM THE PLAINS TOWARD THE UPPER
MISSISSIPPI VALLEY SATURDAY AFTERNOON/NIGHT...HELPING INDUCE SURFACE
PRESSURE FALLS ACROSS THE UPPER MISSISSIPPI VALLEY AND VEERING LOW
LEVEL WINDS MORE SOUTHERLY. WARM/MOIST ADVECTION IN RETURN FLOW WILL
BRING WARM AND HUMID CONDITIONS BACK TO THE FORECAST AREA BY
SUNDAY...WITH THE POTENTIAL FOR A FEW ELEVATED THUNDERSTORMS ACROSS
NORTHWEST IL TOWARD SUNDAY MORNING ALONG EASTERN PERIPHERY OF BROAD
SOUTHWESTERLY LOW LEVEL JET AND THE SUBTLE WARM FRONT. POTENTIAL FOR
THUNDERSTORMS INCREASES AS AREA BECOMES FIRMLY ENTRENCHED IN THE
WARM SECTOR SUNDAY AND SUNDAY NIGHT...WITH TEMPS MID-UPPER 80S AND
DEW POINT TEMPS 65-70 PROGGED.
GUIDANCE DIFFERS WITH DETAILS OF SHORT WAVES MOVING THROUGH
SOUTHWEST FLOW ALOFT INTO EARLY NEXT WEEK...THOUGH THE POTENTIAL
EXISTS FOR SEVERAL ROUNDS OF THUNDERSTORMS TO AFFECT THE REGION INTO
AT LEAST TUESDAY AS COLD FRONT SLOWLY MOVES SOUTH INTO A VERY WARM
AND MOIST AIR MASS. WEST-SOUTHWEST TO EAST-NORTHEAST ORIENTATION OF
BOUNDARY COMBINED WITH HIGH PRECIPITABLE WATER VALUES (1.5-2.0
INCHES PER GFS SOUNDINGS) WILL LIKELY SUPPORT A HEAVY RAINFALL
THREAT...AND INCREASING DEEP LAYER BULK SHEAR ESPECIALLY MON-WED
ALSO SUGGESTS SEVERE MCS POTENTIAL. FOR NOW HAVE MAINTAINED RATHER
BROAD-BRUSHED CHANCE POPS FROM SUNDAY ONWARD...THOUGH DETAILS SUCH
AS THE LOCATION OF THE FRONTAL BOUNDARY (LIKELY MODULATED BY
CONVECTIVE OUTFLOWS)...AS WELL AS INDIVIDUAL LOW-AMPLITUDE WAVES
WILL ULTIMATELY DRIVE CONVECTIVE TRENDS AND TIMING DURING THIS
PERIOD.
RATZER
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 16Z...
* NELY-ELY WINDS ARND 10KT OR SLIGHTLY HIGHER THROUGH EARLY
EVENING.
KREIN
//DISCUSSION...UPDATED 12Z...
IFR/MVFR STRATUS HAS OVERSPREAD THE TERMINALS THIS MORNING AND IS
EXPECTED TO PERSIST FOR A FEW HOURS BEFORE SCATTERING OUT MID TO
LATE THIS MORNING AND RETURNING TO VFR. HIGH PRESSURE OVER THE GREAT
LAKES WILL THEN PROVIDE FAIR WEATHER WITH MODEST NORTHEAST WIND
THROUGH THE REMAINDER OF THE DAY. WINDS WILL GRADUALLY PICK UP
THROUGH THE MORNING...TOPPING OUT A LITTLE OVER 10 KTS BY LATE
MORNING THROUGH THE AFTERNOON HOURS AND EARLY EVENING HOURS.
ANOTHER VFR DAY IS ON TAP TOMORROW WITH WINDS OUT OF THE EAST.
BMD
//ORD AND MDW CONFIDENCE...UPDATED 16Z...
* HIGH CONFIDENCE IN ALL FORECAST ELEMENTS.
KREIN
//OUTLOOK FOR ORD/MDW FOR 00Z SATURDAY-12Z THURSDAY...UPDATED 12Z...
FRIDAY NIGHT THROUGH SATURDAY...VFR.
SUNDAY THROUGH WEDNESDAY...PERIODIC CHANCES FOR THUNDERSTORMS.
PRIMARILY VFR.
BMD
&&
.MARINE...
246 AM CDT
HIGH PRESSURE EXTENDS FROM HUDSON BAY INTO THE CENTRAL GREAT LAKES
REGION WHERE IT WILL SLOWLY MIGRATE TO THE EASTERN LAKES BY
SATURDAY. IN THE MEANTIME...MODEST NORTHEAST TO EAST WINDS WILL
PREVAIL ACROSS LAKE MICHIGAN. WINDS ARE EXPECTED TO BE STRONGEST ON
THE SOUTH END OF THE LAKE WHERE IT MAY PEAK AROUND 15 TO 20 KT THIS
AFTERNOON. A WARM FRONT WILL LIFT ACROSS LAKE MICHIGAN THIS WEEKEND
WITH WINDS VEERING AROUND TO THE SOUTH BY SUNDAY. SOUTH TO SOUTHWEST
WINDS ARE THEN EXPECTED TO PERSIST THROUGH AROUND MIDWEEK WITH
ANOTHER COLD FRONT DROPS ACROSS THE LAKE.
BMD
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...NONE.
&&
$$
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Area Forecast Discussion
National Weather Service Lincoln IL
1036 AM CDT Thu May 29 2014
.DISCUSSION...
ISSUED 1036 AM CDT Thu May 29 2014
Back-door cool front has slipped south to just north of the I-70
corridor. True push of cool/dry air lags well north of the front,
though northeast flow north of the boundary has brought slightly
cooler and less humid air into the far northern CWA with dewpoints
in the low 60s, while upper 60s dewpoints remain over the central
and south. Aloft, water vapor imagery indicates a cutoff low
spinning through the lower MS valley with the northern fringes of
this feature bringing clouds into the southern CWA and lift
producing showers in far southern IL/IN. A separate weak shortwave
was noted in NW IL and is forecast to get absorbed into the
circulation of the upper low as is shifts SE today. 12Z ILX
sounding shows little airmass change from yesterday even as the
front has shifted south. Given afternoon CAPEs near 2000 J/kg and
light wind fields aloft, expect isolated to scattered thunderstorm
development as convective temperatures are reached. Hi-res models
show this possible for much of the CWA except the far north where
somewhat drier air should keep areas north of Peoria and Galesburg
dry. For the bulk of the CWA, slow moving iso/sct storms will
produce brief heavy rain rates. Given high instability and weak
shear with a boundary in the area, isolated land spouts will again
be a concern. Non-supercell tor parameters off RAP and NAM
suggest the central/southern CWA will again be at risk during
early to mid afternoon, especially near the main synoptic boundary or
mesoscale boundary interactions. Raised max temps a degree or two
with highs in the lower 80s.
25
&&
.AVIATION...
ISSUED 600 AM CDT Thu May 29 2014
Areas of MVFR cigs/vsbys possible thru 14z...then VFR conditions
expected into this evening. The front that moved thru our area
last evening has shifted well south of the TAF sites. As a result,
winds have become east to northeast over the entire area and are
expected to remain that way today. A band of MVFR cigs with some
local IFR cigs noted on the latest satellite data just to our
north and east, tracking west and northwest. The bulk of the lower
cigs will remain just to our north over the next few hours but
over the past few hours have noted an increase in stratus on the
southwest flank of the cloud bank so may have to include a period
of IFR cigs at KBMI in the 12z-15z time frame.
Once we burn of the fog/hz and cig restrictions this morning,
forecast soundings suggest a rapid increase in cumulus after 15z
with scattered to broken cigs at or above 5000 feet by late morning
into the afternoon hours. Will continue with VCTS at all TAF sites
but it appears the better coverage of storms will be south of I74
this afternoon. Any convection that does develop this afternoon
should dissipate by early this evening but with the residual low
level moisture in place, we could see some MVFR vsbys develop again
in fog aftr 08z. East to northeast winds will prevail today with
speeds of 8 to 13 kts and the trend more from an east direction
tonight at less than 10 kts.
Smith
&&
.PREV DISCUSSION...
ISSUED 250 AM CDT Thu May 29 2014
Weak frontal boundary centered just north of the I-70 corridor
early this morning. High pressure over the Great Lakes is
providing a northeast flow behind the front, which has dropped dew
points into the 50s from Galesburg to Bloomington northward, while
mid to upper 60s still prevail elsewhere. Still a fair amount of
cloud cover over the forecast area, some streaming north from the
ever-present upper low, now centered in south central Arkansas.
There were a few showers recently near the boundary which drifted
northwest due to that low, although these have now faded out.
Rain chances continue to be the primary forecast concern, with
next week`s chances a bit more challenging due to more model
disagreement.
SHORT TERM...Today through Saturday:
The frontal boundary should be quasi-stationary between the I-72
and I-70 corridors today, and will be the focus for the next round
of scattered showers and storms beginning around noon. Have had
some heavier pockets of rain recently, and with precipitable water
values around 1.5 to 1.6 inches, today shouldn`t be any different.
Severe weather threat remains minimal due to low shear values, but
cannot rule out some isolated funnels or land spouts similar to
yesterday, with the boundary overhead. Non-supercell tornado
parameter from the RAP model focuses on a couple areas, one along
the I-74 corridor just north of the main precipitation area, and
the other along I-72 near the boundary. Any such activity would be
most likely between noon and 4 pm.
The boundary will be pushed southward again tonight as an upper
high slides moves into the upper Mississippi Valley. As it will
not make it terribly far, the convection on Friday and Saturday will
be close by, but mostly out of our forecast area. Have maintained
some 20% PoP`s along the southern CWA border Friday afternoon, but
kept Saturday dry for now.
LONG TERM...Sunday through Wednesday:
Upper ridging breaks down during the weekend with more of a
southwest flow across the nation early next week, and the northern
jet stream along the Canadian border. Right now the ECMWF is the
odd model out in developing an upper low over the upper
Mississippi Valley which slowly drifts eastward through the Great
Lakes during the week, while the GFS, GEM and GFS ensembles have
more of periodic shortwave interaction between the two upper flows.
Sunday into early Monday are in most agreement with rain chances,
but trends widen after that. The ECMWF and the GEM to an extent
have the surface cyclone somewhat in agreement into Tuesday with
the cold front coming through, which would support the rain
chances continuing. Toward mid week, there is much more
uncertainty as the GFS never actually brings the front through and
holds it up near I-80, thus lingering rain chances, while the
ECMWF is dry. Have kept some PoP`s in for Wednesday for now, but
scaled them back from the initial blended guidance.
Geelhart
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS INDIANAPOLIS IN
206 PM EDT THU MAY 29 2014
.UPDATE...
THE LONG TERM SECTION HAS BEEN UPDATED BELOW.
&&
.SYNOPSIS...
ISSUED AT 317 AM EDT THU MAY 29 2014
SCATTERED THUNDERSTORMS ARE EXPECTED ONCE AGAIN TODAY AS A SLOW
MOVING FRONT DROPS SOUTH. THE FRONT WILL EVENTUALLY SLIP SOUTH OF
THE OHIO RIVER TONIGHT AS STRONG HIGH PRESSURE BUILDS IN FROM THE
NORTH. WARM DRY WEATHER IS ANTICIPATED INTO SUNDAY AS THE HIGH
CENTERS OVER THE REGION. A MORE UNSETTLED PATTERN RETURNS FOR THE
FIRST HALF OF NEXT WEEK WITH CHANCES FOR THUNDERSTORMS.
&&
.NEAR TERM /REST OF TODAY/...
ISSUED AT 937 AM EDT THU MAY 29 2014
1330Z UPDATE...FEW CHANGES TO GOING FORECAST...MAINLY TO ACCOUNT
FOR MUCH DRIER TREND EARLY THIS MORNING AND TO DROP FOG FROM
FORECAST. OTHERWISE FORECAST LOOKS TO BE IN PRETTY GOOD SHAPE.
PREVIOUS DISCUSSION FOLLOWS.
ANOTHER STICKY MORNING WITH PLENTY OF CLOUD DEBRIS ACROSS THE
REGION. CONVECTION HAS LARGELY DIMINISHED WITH THE EXCEPTION OF A
SMALL PERSISTENT CELL NEAR KMIE WHICH WAS FINALLY WEAKENING. TEMPS
WERE GENERALLY IN THE 60S AS OF 07Z WITH PATCHY FOG DEVELOPING IN
AREAS THAT RECEIVED RAIN ON WEDNESDAY.
THE CATALYSTS FOR CONVECTIVE DEVELOPMENT WILL BE THE SAME AS THEY
HAVE BEEN THE LAST FEW DAYS...MODEST INSTABILITY AND THE PRESENCE OF
THE SLOWLY SOUTHWARD MOVING FRONTAL BOUNDARY. A REMNANT OUTFLOW
BOUNDARY THAT APPEARS TO BE LOCATED FROM NEAR KHUF SOUTHEAST TO KBMG
AND SEYMOUR IS THE WILDCARD TODAY...AS IT WILL LIKELY BE A FOCAL
POINT FOR STORMS TO FIRE ONCE CONVECTIVE TEMPS ARE MET BY EARLY
AFTERNOON. SHORT RANGE MODEL GUIDANCE ALSO HINTING AT A WEAK AXIS OF
MID LEVEL FORCING ALIGNING NORTHWEST-SOUTHEAST ACROSS THE CENTER OF
THE FORECAST AREA THIS AFTERNOON BEFORE GRADUALLY SHIFTING SOUTH.
WHILE THE GREATEST CONVECTIVE COVERAGE WILL BE FOUND PRIMARILY SOUTH
OF I-70...THE PRESENCE OF THE WEAK FORCING ALOFT SUPPORTS SCATTERED
CONVECTION ALL THE WAY NORTH TO A CRAWFORDSVILLE-NOBLESVILLE-
ANDERSON LINE. HRRR AND WRF REFLECTIVITY PROGS FOR THIS AFTERNOON
BOTH SUPPORT THIS IDEA IN THE 18-21Z TIME PERIOD BEFORE SHIFTING
STORMS SOUTH AS DRIER AIR ATTEMPTS TO ADVECT IN FROM THE NORTHEAST.
WILL CARRY CHANCE POPS FOR ALL BUT THE FAR NORTHERN COUNTIES
TODAY...WITH HIGHEST POPS DURING THE AFTERNOON AND ACROSS THE
SOUTHERN HALF OF THE FORECAST AREA. LARGELY DISORGANIZED
MULTICELLULAR CONVECTION ONCE AGAIN FAVORED IN THE ABSENCE OF BL
SHEAR...WITH TORRENTIAL RAINFALL AND LOCALIZED FLOODING THE PRIMARY
IMPACT AS STORM MOTIONS WILL BE GENERALLY 10KTS OR LESS.
TEMPS...DEPENDING ON HOW QUICKLY STORMS GET GOING...POTENTIAL EXISTS
FOR TEMPS TO OVERACHIEVE A BIT TODAY. WENT AT OR JUST ABOVE WARMER
MAVMOS.
&&
.SHORT TERM /TONIGHT THROUGH SATURDAY NIGHT/...
ISSUED AT 317 AM EDT THU MAY 29 2014
FORECAST CHALLENGES ARE FEW THROUGH THE PERIOD...AS HIGH PRESSURE
ASSERTS CONTROL OVER THE REGION FOR MUCH OF THE SHORT TERM.
ANTICIPATE LINGERING CONVECTION FOCUSED OVER SOUTHERN COUNTIES NEAR
THE REMNANT FRONTAL BOUNDARY THIS EVENING...WITH STORMS DIMINISHING
BY MIDNIGHT AS THE AIRMASS STABILIZES AND PROGRESSIVELY DRIER AIR
SPREADS IN WITH THE HIGH PRESSURE TO THE NORTH. DEEPER MOISTURE AXIS
WILL REMAIN JUST TO THE SOUTHWEST OF THE FORECAST AREA ON
FRIDAY...CLOSE ENOUGH THAT AN ISOLATED STORM CANNOT BE ENTIRELY
RULED OUT OVER THE EXTREME SOUTHWEST FORECAST AREA. HOWEVER WITH
COVERAGE SPARSE AT BEST WILL MAINTAIN A DRY FORECAST.
OVER THE REMAINDER OF THE FORECAST AREA...THE SURFACE HIGH WILL TAKE
ROOT WITH STRONG RIDGING ALOFT ESTABLISHING AS WELL. MODEL SOUNDINGS
AND RH PROGS INDICATE DEEP SUBSIDENCE ACCOMPANYING THE HIGH WITH
ABUNDANT SUNSHINE ANTICIPATED FRIDAY AND SATURDAY AS A PREDOMINANT
DRY E/NE FLOW CONTINUES. ALL IN ALL...SHAPING UP TO BE A GREAT
WEEKEND FOR CENTRAL INDIANA.
TEMPS...DESPITE SLIGHTLY COOLER 850MB TEMPS FRIDAY AND SATURDAY...
PRESENCE OF THE UPPER RIDGE AND ABUNDANT SUNSHINE WILL COMPENSATE
WITH HIGHS INTO THE 80S FRIDAY AND SATURDAY. LEANED TOWARDS WARMER
MAVMOS GUIDANCE BOTH DAYS. EXPECT LOWS INTO THE 50S IN SOME OF OUR
NORMAL COOL SPOTS BOTH TONIGHT AND FRIDAY NIGHT...ESPECIALLY NORTH
AND EAST OF THE INDY METRO. WENT ABOVE GUIDANCE AT INDY FOR LOWS
TONIGHT AND FRIDAY NIGHT WITH A LIGHT E/NE FLOW.
&&
.LONG TERM /SUNDAY NIGHT THROUGH THURSDAY/...
ISSUED AT 202 PM EDT THU MAY 29 2014
UNSETTLED...WARM AND HUMID WEATHER APPEARS IN STORE FOR MUCH OF
NEXT WEEK. ECMWF AND GFS HINT AT RIDGING SETTING UP ALOFT EAST OF
INDIANA...ALLOWING A WARM AND HUMID AIR MASS TO ARRIVE IN THE OHIO
VALLEY ON SOUTHERLY WINDS. UPPER SUPPORT THROUGH THE PERIOD IS
UNORGANIZED AS A FEW WEAK SHORT WAVES APPEAR TO PUSH OUT OF THE
CENTRAL PLAINS INTO THE OHIO VALLEY...HOWEVER...CONFIDENCE REMAINS
QUITE LOW. HOWEVER GIVEN THE VERY WARM AND MOIST AIR MASS THAT
WILL BE IN PLACE...DIURNAL SHRA AND TSRA WILL NOT BE OUT OF THE
QUESTION. THUS WILL TREND TOWARD DAILY CHANCES WITH ABOVE NORMAL
HIGHS AND ABOVE NORMAL LOWS.
&&
.AVIATION /DISCUSSION FOR THE 291800Z IND TAFS/...
ISSUED AT 1210 PM EDT THU MAY 29 2014
MAINLY VFR CONDITIONS ARE EXPECTED THIS TAF PERIOD...HOWEVER BRIEF
MVFR CONDITIONS WILL BE POSSIBLE WITH ANY TSRA THAT DOES STRIKE A
TAF SITE. ALSO VFR CONDITIONS WILL BE POSSIBLE LATE TONIGHT DUE TO
DIURNAL FOG.
WEAK...POORLY DEFINED COLD FRONTAL BOUNDARY STILL LINGERING ACROSS
CENTRAL INDIANA EARLY THIS AFTERNOON. FORECAST SOUNDINGS STILL
REVEAL A CONDITIONALLY UNSTABLE...MOIST AIR MASS OVER THE TAF
SITES. AS CONVECTIVE TEMPERATURES ARE REACHED THIS
AFTERNOON...EXPECT DIURNALLY DRIVEN SCT SHRA/TSRA TO DEVELOP
THROUGH THE PEAK HEATING HOURS OF THE AFTERNOON. WILL CONTINUE TO
USE VCTS TO COVER THIS FOR NOW...BUT WILL UPDATE TAFS QUICKLY IF A
STRIKE ON A TAF SITE APPEARS IMMINENT.
AFTER HEATING IS LOST THIS EVENING...CONVECTIVE ACTIVITY WILL
DISSIPATE AS SUGGESTED BY THE HRRR. TIME HEIGHTS AND FORECAST
SOUNDINGS THEN SHOW DRYER AIR WORKING INTO THE STATE ON EASTERLY
WINDS AS THE COLD FRONT SAGS SLOWLY SOUTHWARD. ANY SPOT THAT DOES
RECEIVE RAIN THIS AFTERNOON MAY HAVE ENOUGH MOISTURE TO RESULT IN
PATCHY MVFR FOG OVERNIGHT DUE TO GOOD LOWER LEVEL MOISTURE AND
IDEAL RADIATIONAL COOLING CONDITIONS.
AMID DRY AIR ON FRIDAY...CONVECTIVE TEMPERATURES ARE EXPECTED TO
BE TOO WARM AND CU DEVELOPMENT IS NOT EXPECTED.
&&
.IND WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...RYAN
NEAR TERM...SMF/RYAN
SHORT TERM...RYAN
LONG TERM....PUMA
AVIATION...JP
VISIT US AT HTTP://WWW.WEATHER.GOV/IND
FOLLOW US ON TWITTER AND YOUTUBE AT:
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AREA FORECAST DISCUSSION
NWS INDIANAPOLIS IN
1227 PM EDT THU MAY 29 2014
.UPDATE...
THE AVIATION SECTION HAS BEEN UPDATED BELOW.
&&
.SYNOPSIS...
ISSUED AT 317 AM EDT THU MAY 29 2014
SCATTERED THUNDERSTORMS ARE EXPECTED ONCE AGAIN TODAY AS A SLOW
MOVING FRONT DROPS SOUTH. THE FRONT WILL EVENTUALLY SLIP SOUTH OF
THE OHIO RIVER TONIGHT AS STRONG HIGH PRESSURE BUILDS IN FROM THE
NORTH. WARM DRY WEATHER IS ANTICIPATED INTO SUNDAY AS THE HIGH
CENTERS OVER THE REGION. A MORE UNSETTLED PATTERN RETURNS FOR THE
FIRST HALF OF NEXT WEEK WITH CHANCES FOR THUNDERSTORMS.
&&
.NEAR TERM /REST OF TODAY/...
ISSUED AT 937 AM EDT THU MAY 29 2014
1330Z UPDATE...FEW CHANGES TO GOING FORECAST...MAINLY TO ACCOUNT
FOR MUCH DRIER TREND EARLY THIS MORNING AND TO DROP FOG FROM
FORECAST. OTHERWISE FORECAST LOOKS TO BE IN PRETTY GOOD SHAPE.
PREVIOUS DISCUSSION FOLLOWS.
ANOTHER STICKY MORNING WITH PLENTY OF CLOUD DEBRIS ACROSS THE
REGION. CONVECTION HAS LARGELY DIMINISHED WITH THE EXCEPTION OF A
SMALL PERSISTENT CELL NEAR KMIE WHICH WAS FINALLY WEAKENING. TEMPS
WERE GENERALLY IN THE 60S AS OF 07Z WITH PATCHY FOG DEVELOPING IN
AREAS THAT RECEIVED RAIN ON WEDNESDAY.
THE CATALYSTS FOR CONVECTIVE DEVELOPMENT WILL BE THE SAME AS THEY
HAVE BEEN THE LAST FEW DAYS...MODEST INSTABILITY AND THE PRESENCE OF
THE SLOWLY SOUTHWARD MOVING FRONTAL BOUNDARY. A REMNANT OUTFLOW
BOUNDARY THAT APPEARS TO BE LOCATED FROM NEAR KHUF SOUTHEAST TO KBMG
AND SEYMOUR IS THE WILDCARD TODAY...AS IT WILL LIKELY BE A FOCAL
POINT FOR STORMS TO FIRE ONCE CONVECTIVE TEMPS ARE MET BY EARLY
AFTERNOON. SHORT RANGE MODEL GUIDANCE ALSO HINTING AT A WEAK AXIS OF
MID LEVEL FORCING ALIGNING NORTHWEST-SOUTHEAST ACROSS THE CENTER OF
THE FORECAST AREA THIS AFTERNOON BEFORE GRADUALLY SHIFTING SOUTH.
WHILE THE GREATEST CONVECTIVE COVERAGE WILL BE FOUND PRIMARILY SOUTH
OF I-70...THE PRESENCE OF THE WEAK FORCING ALOFT SUPPORTS SCATTERED
CONVECTION ALL THE WAY NORTH TO A CRAWFORDSVILLE-NOBLESVILLE-
ANDERSON LINE. HRRR AND WRF REFLECTIVITY PROGS FOR THIS AFTERNOON
BOTH SUPPORT THIS IDEA IN THE 18-21Z TIME PERIOD BEFORE SHIFTING
STORMS SOUTH AS DRIER AIR ATTEMPTS TO ADVECT IN FROM THE NORTHEAST.
WILL CARRY CHANCE POPS FOR ALL BUT THE FAR NORTHERN COUNTIES
TODAY...WITH HIGHEST POPS DURING THE AFTERNOON AND ACROSS THE
SOUTHERN HALF OF THE FORECAST AREA. LARGELY DISORGANIZED
MULTICELLULAR CONVECTION ONCE AGAIN FAVORED IN THE ABSENCE OF BL
SHEAR...WITH TORRENTIAL RAINFALL AND LOCALIZED FLOODING THE PRIMARY
IMPACT AS STORM MOTIONS WILL BE GENERALLY 10KTS OR LESS.
TEMPS...DEPENDING ON HOW QUICKLY STORMS GET GOING...POTENTIAL EXISTS
FOR TEMPS TO OVERACHIEVE A BIT TODAY. WENT AT OR JUST ABOVE WARMER
MAVMOS.
&&
.SHORT TERM /TONIGHT THROUGH SATURDAY NIGHT/...
ISSUED AT 317 AM EDT THU MAY 29 2014
FORECAST CHALLENGES ARE FEW THROUGH THE PERIOD...AS HIGH PRESSURE
ASSERTS CONTROL OVER THE REGION FOR MUCH OF THE SHORT TERM.
ANTICIPATE LINGERING CONVECTION FOCUSED OVER SOUTHERN COUNTIES NEAR
THE REMNANT FRONTAL BOUNDARY THIS EVENING...WITH STORMS DIMINISHING
BY MIDNIGHT AS THE AIRMASS STABILIZES AND PROGRESSIVELY DRIER AIR
SPREADS IN WITH THE HIGH PRESSURE TO THE NORTH. DEEPER MOISTURE AXIS
WILL REMAIN JUST TO THE SOUTHWEST OF THE FORECAST AREA ON
FRIDAY...CLOSE ENOUGH THAT AN ISOLATED STORM CANNOT BE ENTIRELY
RULED OUT OVER THE EXTREME SOUTHWEST FORECAST AREA. HOWEVER WITH
COVERAGE SPARSE AT BEST WILL MAINTAIN A DRY FORECAST.
OVER THE REMAINDER OF THE FORECAST AREA...THE SURFACE HIGH WILL TAKE
ROOT WITH STRONG RIDGING ALOFT ESTABLISHING AS WELL. MODEL SOUNDINGS
AND RH PROGS INDICATE DEEP SUBSIDENCE ACCOMPANYING THE HIGH WITH
ABUNDANT SUNSHINE ANTICIPATED FRIDAY AND SATURDAY AS A PREDOMINANT
DRY E/NE FLOW CONTINUES. ALL IN ALL...SHAPING UP TO BE A GREAT
WEEKEND FOR CENTRAL INDIANA.
TEMPS...DESPITE SLIGHTLY COOLER 850MB TEMPS FRIDAY AND SATURDAY...
PRESENCE OF THE UPPER RIDGE AND ABUNDANT SUNSHINE WILL COMPENSATE
WITH HIGHS INTO THE 80S FRIDAY AND SATURDAY. LEANED TOWARDS WARMER
MAVMOS GUIDANCE BOTH DAYS. EXPECT LOWS INTO THE 50S IN SOME OF OUR
NORMAL COOL SPOTS BOTH TONIGHT AND FRIDAY NIGHT...ESPECIALLY NORTH
AND EAST OF THE INDY METRO. WENT ABOVE GUIDANCE AT INDY FOR LOWS
TONIGHT AND FRIDAY NIGHT WITH A LIGHT E/NE FLOW.
&&
.LONG TERM /SUNDAY THROUGH WEDNESDAY/...
ISSUED AT 317 AM EDT THU MAY 29 2014
AN UPPER RIDGE OVER CENTRAL INDIANA WILL MOVE EAST AND WIND UP OFF
THE EAST COAST BY THE END OF THE LONG TERM. AN UPPER TROUGH OVER THE
WESTERN U.S. WILL ALLOW WEAK SHORTWAVES TO MOVE THROUGH THE FLOW AND
BRING THUNDERSTORM CHANCES TO CENTRAL INDIANA THROUGHOUT THE LONG
TERM. WITH THE SOUTHWESTERLY FLOW OVER THE AREA CONDITIONS WILL
REMAIN WARM AND HUMID AS THE GULF REMAINS OPEN. NO STRONG FEATURES
TO FOCUS ON SO STUCK WITH INITIALIZATION CHANCE POPS FROM SUNDAY
NIGHT ON. FOR SUNDAY MORNING THE UPPER RIDGE WILL JUST BE STARTING
TO MOVE EAST AND THUS THINK PRECIPITATION WILL HAVE A HARD TIME
MOVING EAST INTO THE AREA UNDER UPPER SUBSIDENCE. THUS WENT DRY FOR
SUNDAY MORNING AND BROUGHT IN LOW CHANCE POPS IN THE WEST IN THE
AFTERNOON.
&&
.AVIATION /DISCUSSION FOR THE 291800Z IND TAFS/...
ISSUED AT 1210 PM EDT THU MAY 29 2014
MAINLY VFR CONDITIONS ARE EXPECTED THIS TAF PERIOD...HOWEVER BRIEF
MVFR CONDITIONS WILL BE POSSIBLE WITH ANY TSRA THAT DOES STRIKE A
TAF SITE. ALSO VFR CONDITIONS WILL BE POSSIBLE LATE TONIGHT DUE TO
DIURNAL FOG.
WEAK...POORLY DEFINED COLD FRONTAL BOUNDARY STILL LINGERING ACROSS
CENTRAL INDIANA EARLY THIS AFTERNOON. FORECAST SOUNDINGS STILL
REVEAL A CONDITIONALLY UNSTABLE...MOIST AIR MASS OVER THE TAF
SITES. AS CONVECTIVE TEMPERATURES ARE REACHED THIS
AFTERNOON...EXPECT DIURNALLY DRIVEN SCT SHRA/TSRA TO DEVELOP
THROUGH THE PEAK HEATING HOURS OF THE AFTERNOON. WILL CONTINUE TO
USE VCTS TO COVER THIS FOR NOW...BUT WILL UPDATE TAFS QUICKLY IF A
STRIKE ON A TAF SITE APPEARS IMMINENT.
AFTER HEATING IS LOST THIS EVENING...CONVECTIVE ACTIVITY WILL
DISSIPATE AS SUGGESTED BY THE HRRR. TIME HEIGHTS AND FORECAST
SOUNDINGS THEN SHOW DRYER AIR WORKING INTO THE STATE ON EASTERLY
WINDS AS THE COLD FRONT SAGS SLOWLY SOUTHWARD. ANY SPOT THAT DOES
RECEIVE RAIN THIS AFTERNOON MAY HAVE ENOUGH MOISTURE TO RESULT IN
PATCHY MVFR FOG OVERNIGHT DUE TO GOOD LOWER LEVEL MOISTURE AND
IDEAL RADIATIONAL COOLING CONDITIONS.
AMID DRY AIR ON FRIDAY...CONVECTIVE TEMPERATURES ARE EXPECTED TO
BE TOO WARM AND CU DEVELOPMENT IS NOT EXPECTED.
&&
.IND WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...RYAN
NEAR TERM...SMF/RYAN
SHORT TERM...RYAN
LONG TERM....CP
AVIATION...JP
VISIT US AT HTTP://WWW.WEATHER.GOV/IND
FOLLOW US ON TWITTER AND YOUTUBE AT:
WWW.TWITTER.COM/NWSINDIANAPOLIS
WWW.YOUTUBE.COM/NWSINDIANAPOLIS
AREA FORECAST DISCUSSION
NWS QUAD CITIES IA IL
1253 PM CDT THU MAY 29 2014
.UPDATE...
ISSUED AT 1248 PM CDT THU MAY 29 2014
NEW CONVECTION HAS DEVELOPED FROM NORTHERN MISSOURI INTO CENTRAL
ILLINOIS. BASED ON SUGGESTED DATA AND RAP TRENDS...NEW DIURNAL
CONVECTION SHOULD BEGIN DEVELOPING AND INCREASING ACROSS THE
SOUTH THIRD THIS AFTERNOON. IF THE GEM TRENDS ARE CORRECT...
CONVECTION MAY APPROACH I-80 BY LATE AFTERNOON.
UPDATE ISSUED AT 1117 AM CDT THU MAY 29 2014
THE LOW STRATUS THAT ADVECTED IN FROM INDIANA ACROSS THE NORTHEAST
AREAS HAS DISSIPATED AS ARE THE ISOLATED SHOWERS OVER THE FAR SOUTHWEST.
SATELLITE TRENDS SHOW NEW CONVECTIVE CLOUDS HAVE DEVELOPED IN THE
PAST HOUR FROM NORTHERN MISSOURI INTO CENTRAL ILLINOIS. BASED ON
CLOUD RATE GROWTH...NEW DIURNAL CONVECTION WILL BE DEVELOPING IN
ERNEST OVER THE NEXT 90 MINUTES.
&&
.SYNOPSIS...
ISSUED AT 310 AM CDT THU MAY 29 2014
THE BACK DOOR COOL FRONT HAS MADE ITS WAY THROUGH MUCH OF THE CWA BY
2 AM THIS MORNING. MODELS ARE NOT EVEN REMOTELY CLOSE IN HANDLING
THIS. THE MAIN IMPACT BETWEEN FORECAST MODELS AND OBSERVED DATA IS
THAT ACTUAL DEWPOINTS ARE FALLING FASTER AS THIS AIRMASS IS QUITE
DRY...AT LEAST AT SHALLOW LEVELS. DEWPOINTS IN THE MID 40S TO LOWER
50S ARE SPREADING WEST INTO THE CWA...AND SHOULD ESTABLISH AT LEAST
WIDESPREAD 50S BY SUNRISE IN ALL LOCATIONS. TEMPERATURES ARE ALSO
FALLING...INTO THE MID 50S NORTHEAST ALREADY. THE SOUTHWEST...STILL
NEAR THE FRONT...REMAINS MILD AND MOIST BUT WILL EVENTUALLY FALL BY
SUNRISE.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 310 AM CDT THU MAY 29 2014
THE MODEL MOISTURE PROBLEM WILL CERTAINLY IMPACT TODAYS FORECAST. I
WILL KEEP OUR SHARP GRADIENT BETWEEN SLIGHT/CHC POPS IN THE FAR
SOUTH TO AROUND ZERO NORTH OF INTERSTATE 80 GOING TODAY AS DIURNAL
DRIVEN CONVECTION REMAINS POSSIBLE NEAR THE BOUNDARY. HOWEVER...I AM
FARTHER SOUTH THAN MODELS DUE TO THE DRY AIR INTRUSION BEING MORE
AGGRESSIVE THAN MODELS HAVE. AGAIN...THIS SEEMS TO BE ONLY A SHALLOW
FEATURE...AS WE CONTINUE TO HAVE PLENTY OF PATCHY MID CLOUDS AROUND
POST FRONTAL. THUS...THE POPS WILL REMAIN IN THE SOUTH VS TOTALLY
REMOVING THEM. TEMPERATURES TODAY SHOULD REBOUND NICELY...TO THE
UPPER 70S NORTHEAST TO LOWER 80S SOUTHWEST. WITH DRY AIR IN PLACE IN
AT LOW LEVELS...AND CROPS NOT YET LARGE IN SIZE...WE SHOULD ONLY
REBOUND DEWPOINTS TO AROUND 57 TO 60 EXCEPT IN THE FAR SOUTH WERE
SOME MID 60S ARE POSSIBLE. THIS WILL MAKE FOR A VERY PLEASANT LATE
SPRING DAY FOR MOST OF THE CWA.
TONIGHT...WITH LIGHT EAST FLOW CONTINUING...IT WILL BE ANOTHER GOOD
NIGHT TO LEAVE THE WINDOWS OPEN. LOWS WILL ONCE AGAIN FALL TO THE
LOWER 50S TO LOWER 60S FROM EAST TO WEST. WE WILL MISS THIS WEATHER
ONCE THE TRUE HEAT OF SUMMER ARRIVES.
ERVIN
.LONG TERM...(FRIDAY THROUGH WEDNESDAY)
ISSUED AT 310 AM CDT THU MAY 29 2014
HIGHER HUMIDITY AND RAIN CHANCES CREEP BACK INTO THE FORECAST
SATURDAY ONWARD AS THE SURFACE HIGH OVER THE GREAT LAKES EDGES EAST
AND THE UPPER RIDGE GIVES WAY TO A MORE ACTIVE...NEARLY ZONAL FLOW
THAT WILL PERSIST THROUGH AT LEAST THE MIDDLE PART OF NEXT WEEK.
FRIDAY...HIGH PRESSURE CENTERED OVER LOWER MI WILL CONTINUE TO
CHANNEL A DRY EASTERLY FLOW MAINTAINING LOW DEWPOINTS...ESPECIALLY
OVER NORTHEAST HALF OF THE FORECAST AREA. SIMILAR TO THIS
MORNING...SUSPECT MODELS ARE OVERDONE WITH FORECAST DEWPOINTS IN THE
60S AND EVEN LOWER 70S OVER THE SOUTH...WHEN WIDESPREAD 50S AND
POSSIBLY A FEW UPPER 40S WILL BE MORE LIKELY IN THIS AIRMASS.
LARGELY BASED ON THESE SUSPICIOUS HIGHER DEWPOINTS AND ASSOCIATED
HIGHER CAPES...MODELS BREAKOUT CONVECTION OVER NORTHEAST MO...SE IA
AND W CENTRAL IL DURING THE DAY. CONSIDERING THIS BIAS ALONG WITH
THE LACK OF FOCUSING BOUNDARIES AND SUPPRESSION FROM THE UPPER RIDGE
OVERHEAD...WILL CONTINUE TO UNDERCUT GUIDANCE POPS AND PROVIDE ONLY
SLIGHT TO LOW END CHANCES FOR THUNDERSTORMS OVER THE FAR SOUTH AND
SOUTHWEST IN THE AFTERNOON. OTHERWISE...IT SHOULD BE A MOSTLY SUNNY
DAY WITH HIGHS REACHING AROUND 80 TO THE LOWER 80S. THE DRY AIRMASS
WILL REMAIN IN PLACE OVERNIGHT...WITH LIGHT WINDS ALLOWING
TEMPERATURES TO COOL TO A RANGE FROM THE MID 50S EAST AND NORTH TO
THE LOWER 60S SOUTH AND WEST.
SATURDAY...THE UPPER RIDGE AXIS SHIFTS TO THE EAST WITH MORE
SOUTHERLY SURFACE WINDS BEGINNING TO RETURN HIGHER LOW LEVEL
MOISTURE INTO THE AREA DURING THE DAY. THE INCREASING MOISTURE AND
TRIGGER FROM A WEAK UPPER LEVEL IMPULSE MAY BE SUFFICIENT TO PRODUCE
THUNDERSTORMS OVER THE WEST AND HAVE LOW CHANCE POPS FOR THE
AFTERNOON. FORECAST THERMAL FIELDS INDICATE HIGHS AGAIN REACHING THE
LOWER TO POSSIBLY MID 80S.
SUNDAY ONWARD...THE UPPER RIDGE TO THE EAST FLATTENS GIVING WAY TO
AN ACTIVE WAVE-TRAIN OF UPPER LEVEL SHORTWAVES THROUGH THE REGION
FOR MUCH OF NEXT WEEK. THIS LEADS TO AN EXTENDED PERIOD OF RAIN AND
THUNDERSTORM CHANCES AS RETURNING GULF MOISTURE INTERACTS WITH A
FRONTAL BOUNDARY. THE MOST NOTABLE CHANGE IN THE 00Z MODEL RUN WAS
THE NOW OUTLIER ECMWF WITH ITS STRONGER SURFACE LOW AND CLOSED UPPER
LOW ROLLING BY TO THE NORTH MONDAY AND TUESDAY IN CONTRAST TO THE
MORE CONSISTENT GFS...AND TO SOME EXTENT UKMET AND GEM THAT HAVE A
MUCH WEAKER INITIAL LOW/SHORTWAVE AND THEN A LINGERING FRONT OVER THE
AREA THROUGH WED. EITHER SCENARIO POINTS TOWARD HIGHER CONSENSUS
POPS ON MONDAY ACROSS THE NORTH...WHERE WE HAVE GONE WITH LIKELY
POPS. HIGH END CHANCE POPS ARE THEN CARRIED THROUGH MID WEEK LARGELY
BASED ON THE NON-ECMWF SOLUTIONS. THIS SETUP WOULD BE FAVORABLE FOR
A THREAT OF HEAVY RAINFALL AND POSSIBLE SEVERE STORMS FROM MONDAY
NIGHT THROUGH WED. HIGHS ARE ADVERTISED IN THE 80S FOR MONDAY...THEN
UPPER 70S TO LOWER 80S TUE AND WED...WHERE CONFIDENCE IN
TEMPERATURES IS LOWER DUE TO UNCERTAINTIES IN THE CRITICAL LOCATION
OF THE BOUNDARY. HIGH DEWPOINTS WILL HOLD MINS IN THE 60S TO AROUND
70 THROUGHOUT.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z FRIDAY AFTERNOON)
ISSUED AT 1248 PM CDT THU MAY 29 2014
MAINLY VFR CONDITIONS WILL BE SEEN THROUGH 06Z/30 EXCEPT AROUND
SHRA/TSRA THAT MAY BRIEFLY CREATE MVFR/IFR CONDITIONS. KBRL HAS
THE BEST CHANCE OF BEING IMPACTED BY A SHRA/TSRA. AFT 06Z/30
MAINLY VFR CONDITIONS ARE EXPECTED BUT THE POTENTIAL DOES EXIST
FOR MVFR VSBYS/CLOUDS TO DEVELOP.
&&
.DVN WATCHES/WARNINGS/ADVISORIES...
IA...NONE.
IL...NONE.
MO...NONE.
&&
$$
UPDATE...08
SYNOPSIS...ERVIN
SHORT TERM...ERVIN
LONG TERM...SHEETS
AVIATION...08
AREA FORECAST DISCUSSION
NWS SHREVEPORT LA
1206 PM CDT THU MAY 29 2014
.AVIATION...
UPPER LOW OVER SOUTHCENTRAL AR...TO RETROGRADE SLOWLY SWWD THRU
PERIOD. MOISTURE WRAPPING AROUND NORTH SIDE OF LOW WILL LIKELY
AFFECT SW AR TERMINALS OF KTXK AND KELD...AND KMLU...BY MID
AFTN...WITH SCATTERED TO NUMEROUS CONVECTIVE COVERAGE. CONVECTION
MAY HOLD OFF CLOSER TO 30/00Z AT REMAINING TERMINAL SITES...AS
UPPER LOW BEGINS TO MOVE OVHD. THIS AFTN...EXPECT HIGH MVFR TO LOW
VFR CIGS TO PERSIST UNTIL AROUND 30/04-07Z...WITH LOWERING CIGS
AND POSSIBLY PATCHY DENSE FOG AND IFR CIGS LATER TONIGHT. MOSTLY
LIGHT AND VRBL WINDS...CIRCULATING AROUND LOW PRESSURE./VII/
&&
.PREV DISCUSSION... /ISSUED 1100 AM CDT THU MAY 29 2014/
DISCUSSION...
THE UPPER LOW REMAINS CENTERED OVER EXTREME SE AR THIS MORNING...WITH
THE SHORT TERM PROGS IN GENERAL AGREEMENT WITH THE LOW WOBBLING OVER
THIS AREA AND NE LA THROUGH THE AFTERNOON BEFORE SLOWLY RETROGRADING W
INTO SW AR/NW LA TONIGHT. A 40NM MILE WIDE BAND OF CONVECTION OVER
SCNTRL AND NE LA AHEAD OF THE LOW HAS NOT SHOWN ANY WWD BACKBUILDING
INTO THE ERN SECTIONS OF NCNTRL LA THIS MORNING...WITH THE HRRR AND
12Z NAM MAINTAINING THIS CONVECTION JUST E OF THE REGION THROUGH AT
LEAST EARLY AFTERNOON BEFORE SHUNTING IT E ACROSS THE MS RIVER.
HOWEVER...VISIBLE SATELLITE DOES REVEAL TOWERS DEVELOPING OVER MUCH OF
THE REGION...WITH A MORE AGITATED CU FIELD NEAR/NW OF THE CLOSED LOW
OVER WCNTRL AR/SE OK. WITH ADDED HEATING...SHOULD SEE SCT CONVECTION
DEVELOP WITHIN THE NEXT HOUR OR SO OVER THESE AREAS...WHICH WOULD
SHIFT SSW INTO EXTREME NE TX/SW AR/NW LA DURING THE AFTERNOON.
DID REDUCE POPS THIS MORNING AREAWIDE GIVEN THE LACK OF CONVECTION
ATTM...AND ALSO TONED DOWN POPS SLIGHTLY /TO LIKELY/ ACROSS SCNTRL
AR/ERN SECTIONS OF NCNTRL LA. MID/HIGH CHANCE POPS SHOULD SUFFICE OVER
MUCH OF E TX/WCNTRL LA...FARTHER AWAY FROM THE CENTER OF THE CLOSED
LOW. MUCH OF THIS CONVECTION SHOULD WIND DOWN THIS EVENING WITH THE
LOSS OF HEATING.
DID MAKE MINOR ADJUSTMENTS TO MAX TEMPS THIS AFTERNOON...MAINLY TO
LOWER THEM A COUPLE DEGREES ACROSS SW AR...AND ALSO RAISING THEM
SLIGHTLY ACROSS THE WRN SECTIONS OF E TX WHICH ARE ALREADY IN THE
MID/UPPER 70S AS OF 1530Z. OTHERWISE...THE REMAINDER OF THE FORECAST
IS ON TRACK.
ZONE UPDATE ALREADY OUT...GRIDS WILL BE AVAILABLE SHORTLY.
15
&&
.PRELIMINARY POINT TEMPS/POPS...
SHV 81 68 83 68 86 / 60 30 70 30 50
MLU 80 67 82 67 86 / 70 30 70 30 50
DEQ 79 67 83 67 85 / 60 30 70 30 40
TXK 80 67 83 67 86 / 60 40 70 40 50
ELD 78 67 83 66 86 / 70 40 60 30 50
TYR 84 68 83 68 85 / 40 20 60 40 30
GGG 82 68 83 68 86 / 40 30 60 40 30
LFK 84 68 83 69 86 / 30 30 60 30 40
&&
.SHV WATCHES/WARNINGS/ADVISORIES...
AR...NONE.
LA...NONE.
OK...NONE.
TX...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS TAUNTON MA
701 PM EDT THU MAY 29 2014
.SYNOPSIS...
ANOTHER NIGHT OF COOL AND DRY WEATHER FOLLOWED BY A COLD FRONT
WITH SHOWERS AND THUNDERSTORMS FRIDAY INTO FRIDAY NIGHT. COOL
WEATHER LINGERS THROUGH THE WEEKEND...BUT EXPECT WARMER CONDITIONS
INTO EARLY NEXT WEEK PRIOR TO A RENEWED THREAT OF WET-WEATHER BY
MIDWEEK.
&&
.NEAR TERM /UNTIL 6 AM FRIDAY MORNING/...
7 PM UPDATE...
FORECAST IN GOOD SHAPE. ONLY FEW HIGH CLOUDS OVER REGION THIS
EVENING WITH MORE SOLID CLOUD COVER REMAINING BACK ACROSS NEW YORK
STATE. HIGH-RES RAP STILL INSISTS ON LOW CLOUDS/FOG REACHING S
COAST OVERNIGHT. EARLIER DISCUSSION FOLLOWS...
MOSTLY CLEAR SKIES AND LIGHT WINDS WILL LEAD TO ANOTHER EVENING
OF EFFECTIVE RADIATIONAL COOLING. HIGHEST CONFIDENCE ACROSS SE
MA...W-CAPE...AND MARTHAS VINEYARD. WOULD NOT BE SURPRISED TO HAVE
A FEW LOCALES IN THOSE AREAS FALL BELOW 40-DEGREES. THOSE AREAS
THAT RADIATE OUT EFFECTIVELY...WOULD EXPECT PATCHY GROUND FOG.
SOME UNCERTAINTY...WATCHING THE CLOUD DECK WELL OFFSHORE. PLAUSIBLE
THAT WITH S/SE WINDS LOW CLOUDS AND FOG WILL IMPACT THE S-COASTLINE
OF NEW ENGLAND. WILL PREVAIL IN THE FORECAST ACROSS SE CAPE COD
WHERE CONFIDENCE IS HIGHEST. UNCERTAIN AS TO ELSEWHERE. WILL LEAVE
FOR THE OVERNIGHT CREW TO ASSESS.
TO THE W...MID-LEVEL IMPULSE AND ACCOMPANYING TROUGH SWEEP NW-SE
THROUGH THE REGION. BROKEN-OVERCAST CLOUDS VIA SATELLITE ACROSS THE
MID-ATLANTIC TO LAKE ONTARIO ADVECT N AND W IN RESPONSE TO ASCENT
AHEAD OF THE TROUGH AXIS. SOME LIGHT SHOWER ACTIVITY ACROSS N/W-
FACES OF HIGHER TERRAIN IS POSSIBLE. SHOULD SEE MILDER CONDITIONS WITH
LOWS DOWN TO AROUND THE UPPER-40S UNDER LIGHT S/SW-WINDS.
&&
.SHORT TERM /6 AM FRIDAY MORNING THROUGH FRIDAY NIGHT/...
FRIDAY INTO FRIDAY NIGHT...
ANOTHER MID-LEVEL IMPULSE DIVES NW-SE ACROSS THE NE-CONUS DURING THE
DAY. SUBSEQUENT TROUGHING AND FALLING HEIGHTS PARENT WITH A COLD
FRONT YIELDS AN AREA OF STRONG ASCENT OVER MUCH OF S NEW ENGLAND
BENEATH CYCLING FLOW AND MOIST-ADIABATIC MID-LEVEL LAPSE RATES OF
6C PER KM. EXPECTING A POSSIBLE LINE OF SHOWERS AND
THUNDERSTORMS.
BUT SOME CONSIDERATIONS TO POINT OUT:
WITH CLOUDS ADVECTING E OVERNIGHT WILL ASSUME LESSER DESTABILIZATION
TO THE W. ANTICIPATE CENTRAL-S/E PORTIONS OF S NEW ENGLAND TO SEE
SUNSHINE ALLOWING BOUNDARY-LAYER MIXING AND LOW-LEVEL LAPSE RATES TO
STEEPEN TO DRY-ADIABATIC. INSTABILITY SUBSEQUENTLY BUILDS TO AROUND
500 J/KG...AN AXIS OF WHICH WILL EXIST OVER THE INTERIOR AWAY
FROM THE IMMEDIATE COAST WITH ANTICIPATED ONSHORE SEA-BREEZE
BEHIND WHICH COOLER AND MORE STABLE AIR PREVAILS.
ALSO MUST NOTE THAT STRONGEST WINDS AND BETTER DYNAMICS RESIDE WELL
W OF THE REGION. WHILE NW-SE UNIDIRECTIONAL SHEAR PREVAILS...IT IS
MINOR TO MODEST AT MOST...NOT OVERWHELMING. MORE NOTABLY...0-6 KM
MEAN WINDS NW-SE ARE LIGHT AND CARVED VECTORS ARE NEAR-ZERO.
TAKING THE POINTS ABOVE INTO CONSIDERATION AND EVALUATING HIGH-RES
FORECAST MODELS ALONG WITH THE WEAK WIND PATTERN...ANTICIPATE A LINE
OF SHOWERS TO DEVELOP INITIALLY ALONG THE FRONT...BUT AS IT RACES SE
IT IS LIKELY TO INTERACT WITH A MORE UNSTABLE AIRMASS AND CLASH WITH
THE ONSHORE SEA-BREEZE. EXACTLY WHERE IS SOMEWHAT UNCERTAIN. HIGHEST
CONFIDENCE ACROSS THE INTERIOR W OF THE SEA-BREEZE FRONT.
SHOULD SEE EMBEDDED HEAVY RAIN AND THUNDERSTORMS. LOW CONFIDENCE
CONCERNING SEVERE WEATHER THREATS YET CAN NOT RULE OUT POSSIBLE
HAIL AS WET-BULB FREEZING LEVEL HEIGHTS ARE LOW AROUND 7 KFT. AM
MORE CONCERNED WITH THE THREAT OF HEAVY RAIN ALONG WITH URBAN AND
POOR DRAINAGE FLOODING ESP ALONG THE N/W FACING SLOPES OF HIGH
TERRAIN. PWATS UP TO AN INCH ARE FORECAST. WILL INSERT THE THREAT
OF HEAVY RAIN INTO THE FORECAST. HIGHS GETTING UP TO 70-DEGREES.
ACTIVITY TO LINGER INTO THE EVENING PERIOD GRADUALLY DISSIPATING
OVERNIGHT. CLOUDS AND LIGHT SHOWERY WEATHER LIKELY TO LINGER WITHIN
THE CYCLONIC CONVERGENT FLOW ACROSS E NEW ENGLAND...BUT ALL ASIDE
WITH WINDS PREVAILING OUT OF THE N ANOTHER CHILLY NIGHT IS EXPECTED.
&&
.LONG TERM /SATURDAY THROUGH THURSDAY/...
HIGHLIGHTS...
* COOL ONSHORE FLOW SAT WITH FEW A SHOWERS INLAND
* DRY AND WARMER SUN/MON
* SHOWERS AT TIMES TUE-THU WITH NEAR AVERAGE TEMPS
OVERVIEW...ENSEMBLES AND MEDIUM RANGE MODELS REMAIN IN GOOD
AGREEMENT THROUGH EARLY NEXT WEEK...THEN DIVERGE SIGNIFICANTLY FOR
MID TO LATE WEEK WHICH LENDS LOW CONFIDENCE IN FORECAST. CLOSED LOW
WELL OFF NEW ENGLAND COAST HEADS FARTHER OUT TO SEA SAT...WHICH
ALLOWS SOME OF MIDWEST RIDGING TO SHIFT E INTO OUR AREA SUN/MON.
RIDGE BREAKS DOWN FROM THERE AS NEXT UPPER TROUGH SWINGS DOWN OUT OF
NORTHERN PLAINS. MODELS/ENSEMBLES VARY CONSIDERABLY WITH STRENGTH
AND POSITION OF THIS FEATURE AS IT REACHES GREAT LAKES/NORTHEAST MID
TO LATE WEEK...WHICH AFFECTS POSITION OF WARM FRONT WHICH SHOULD
BECOME STATIONARY NEAR NEW ENGLAND.
SATURDAY...HIGH CONFIDENCE.
LAST SHORT WAVE ROTATING AROUND UPPER LOW WELL OFFSHORE SHOULD
PRODUCE SCATTERED SHOWERS/ISOLATED THUNDER AS COLD TEMPERATURES
ALOFT /NEAR -20C AT 500 MB/ YIELD STEEP MID LEVEL LAPSE RATES.
ACTIVITY SHOULD BECOME FOCUSED OVER WESTERN NEW ENGLAND BY AFTERNOON
AS DRIER AIR ADVECTS IN FROM OCEAN. ONSHORE FLOW WILL KEEP HIGHS IN
60S TO NEAR 70.
SUNDAY AND MONDAY...HIGH CONFIDENCE.
HIGH PRESSURE BUILDS OVER NEW ENGLAND SUN WITH PLENTY OF SUNSHINE
AND AFTERNOON SEA BREEZES. SW FLOW GETS UNDERWAY MON AS HIGH BUILDS
TO MID ATLANTIC COAST WITH INCREASING CLOUDS DURING AFTERNOON AHEAD
OF NEXT SYSTEM. SCATTERED SHOWERS SHOULD ARRIVE MON NIGHT. HIGHS
SHOULD TOP OUT IN 60S COAST/70S INLAND SUN THEN WARM INTO 70S/NEAR
80 MON AWAY FROM S COAST /60S/.
TUESDAY THROUGH THURSDAY...LOW CONFIDENCE.
FORECAST HINGES ON POSITION OF WARM FRONT WHICH IS HIGHLY UNCERTAIN
THIS FAR OUT IN TIME...BUT SHOULD BECOME STATIONARY OVER OR JUST S
OF NEW ENGLAND. EXPECT TO SEE AT LEAST SCATTERED SHOWERS DURING THIS
PERIOD...ESPECIALLY TUE AND AGAIN WED NIGHT/THU PER ENSEMBLES...BUT
ALL THREE DAYS LIKELY TO FEATURE GOOD AMOUNT OF CLOUDS AND S/SE
FLOW. RELYING HEAVILY ON BLEND OF MODEL GUIDANCE WITH HIGHS IN
60S/70S EACH DAY.
&&
.AVIATION /00Z FRIDAY THROUGH TUESDAY/...
FORECASTER CONFIDENCE LEVELS...
LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.
SHORT-TERM /THROUGH FRIDAY/...MODERATE CONFIDENCE.
VFR. SEA BREEZES DECAY THIS EVENING. IFR CIGS/VSBYS STILL ON TRACK
TO REACH CAPE COD AND ISLANDS AFTER 06Z AND SHOULD DISSIPATE
AROUND SUNRISE.
HIGHER CONFIDENCE WITH THE DEVELOPMENT OF SHRA/TSRA SWEEPING NW
TO SE BEGINNING FRIDAY MIDDAY AND CONTINUING INTO THE EVENING.
ACCOMPANYING TEMPO MVFR-IFR CONDITIONS POSSIBLE.
KBOS TAF...HIGH CONFIDENCE IN TAF.
KBDL TAF...HIGH CONFIDENCE IN TAF.
OUTLOOK...SATURDAY THROUGH TUESDAY...
SATURDAY...HIGH CONFIDENCE. VFR EXCEPT SCT SHOWERS/LOCAL MVFR ACROSS
WESTERN NEW ENGLAND.
SUNDAY AND MONDAY...HIGH CONFIDENCE. VFR. SEA BREEZES SUN AFTERNOON.
TUESDAY...MODERATE CONFIDENCE. MVFR IN SCT SHOWERS.
&&
.MARINE...
FORECASTER CONFIDENCE LEVELS...
LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.
.SHORT-TERM /THROUGH FRIDAY/...HIGH CONFIDENCE.
WHILE QUIET BOATING WEATHER IS EXPECTED...WINDS WILL VEER OUT OF
THE S. THERE IS THE CHANCE OF SHOWERS AND POSSIBLY THE THREAT OF
THUNDERSTORMS FRIDAY EVENING.
OUTLOOK...SATURDAY THROUGH TUESDAY...
SATURDAY...HIGH CONFIDENCE. NE WINDS AS LOW PRESSURE PASSES WELL SE
OF NEW ENGLAND...STRONGEST NEAR CAPE COD/ISLANDS BUT SHOULD REMAIN
BELOW SCA. SEAS MAY REACH 5 FT WELL OFFSHORE.
SUNDAY AND MONDAY...HIGH CONFIDENCE. HIGH PRESSURE BUILDS OVER NEW
ENGLAND WITH AFTERNOON SEA BREEZES SUN...THEN MORE OF S/SW FLOW MON
AS HIGH SHIFTS S OF WATERS. LEFTOVER E SWELL NEAR 5 FT MAY PERSIST
ON OUTER WATERS.
TUESDAY...MODERATE CONFIDENCE. S/SE FLOW GETS UNDERWAY AHEAD OF
APPROACHING WARM FRONT WITH SCATTERED SHOWERS. WINDS SHOULD REMAIN
BELOW SCA BUT SEAS ON OUTER WATERS MAY REACH 5 FT.
&&
.BOX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
MA...NONE.
NH...NONE.
RI...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...SIPPRELL/JWD
NEAR TERM...JWD
SHORT TERM...SIPPRELL
LONG TERM...JWD
AVIATION...SIPPRELL/JWD
MARINE...SIPPRELL/JWD
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
139 PM EDT THU MAY 29 2014
.SYNOPSIS...
A SLOW MOVING COLD FRONT WILL STALL ACROSS THE EASTERN CAROLINAS
TODAY AND FRIDAY...CREATING WIDESPREAD SHOWERS AND THUNDERSTORMS.
HIGH PRESSURE WILL BUILD DOWN FROM THE NORTH OVER THE WEEKEND
BRINGING DRIER AND COOLER AIR TO THE REGION. THIS HIGH PRESSURE
WILL PUSH OFFSHORE ON MONDAY...WITH A WARMING TREND EXPECTED INTO
THE MIDDLE OF NEXT WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 1:30 PM THURSDAY...FIRST SHOWERS OF THE DAY BREAKING OUT
RIGHT ON SCHEDULE. NO LIGHTNING THUS FAR...BUT EXPECT
THUNDERSTORMS TO FORM SHORTLY. BASED ON LATEST ANALYSIS AND SPC
DISCUSSION LOOKS LIKE SEVERE POTENTIAL A BIT LESS THAN EARLIER
EXPECTED...ALTHOUGH WE STILL CANNOT RULE IT OUT. ATMOSPHERE MAY
TREND MORE TOWARDS THE MODERATELY UNSTABLE CATEGORY THAN THE
STRONGLY UNSTABLE. HAVE TONED BACK SEVERE WORDING IN THE ZONES
WITH THE LATEST ISSUANCE...OTHERWISE FORECAST CONTINUES WITH
LITTLE CHANGE. COLD FRONT IS CURRENTLY DROPPING SOUTH ACROSS OUR
NC COUNTIES. PREVIOUS DISCUSSIONS FOLLOW:
ANALYSIS OF MORNING SOUNDINGS AND LATEST DATA CONFIRM A MODERATELY
TO STRONGLY UNSTABLE AND MOIST AIRMASS TODAY WITH WEAK VERTICAL
SHEAR AND A BOUNDARY-RICH ENVIRONMENT. ALSO...A COLD FRONT
CONTINUES TO STEADILY ADVANCE SOUTH AND IS NOW ENTERING PENDER
COUNTY. THIS CONFIRMS EARLIER PROGNOSIS...SEE DISCUSSION
BELOW...OF A CONVECTIVE-LY ACTIVE AFTERNOON AND EVENING WITH
PULSE-TYPE CONVECTION BRINGING THE THREAT OF HEAVY RAIN...FREQUENT
LIGHTNING AND DAMAGING WINDS. LATEST HRRR DATA AND MODEL SOUNDINGS
INDICATE STORMS WILL BEGIN TO FIRE UP IN THE 1 TO 2 PM TIME-FRAME.
FORECAST REMAINS ON TRACK. SEE PREVIOUS DISCUSSION BELOW:
A COLD FRONT CURRENTLY DROPPING SOUTH EAST-CENTRAL NORTH CAROLINA
WILL REACH SOUTHEASTERN NORTH CAROLINA BY NOON...SLOWING AND
PRACTICALLY STALLING AS SUCH FRONTS OFTEN DO DURING INTENSE SOLAR
HEATING. THIS FRONT IS A SEPARATE ENTITY FROM A CONVECTIVE OUTFLOW
BOUNDARY WHICH HAS STALLED IN THE VICINITY OF THE NC/SC STATE
LINE. THIS OUTFLOW BOUNDARY ORIGINATED FROM A LARGE CLUSTER OF
OVERNIGHT STORMS IN NORTHEASTERN NORTH CAROLINA. THE BOUNDARY WAS
EARLIER VISIBLE ON RADAR LOOPS AND ALTHOUGH IS DIFFICULT TO FIND
NOW...IT WILL ALMOST CERTAINLY BECOME VISIBLE THIS AFTERNOON WHEN
STORMS BEGIN TO FIRE.
THE ENVIRONMENT SHOULD BECOME MODERATELY TO STRONGLY UNSTABLE THIS
AFTERNOON WITH SURFACE-BASED CAPE RISING TO 2000-3000 J/KG AND
LIFTED INDICES FALLING TO NEAR -7. SYNOPTIC SCALE LOW-LEVEL
CONVERGENCE WILL BECOME MAXIMIZED ALONG THE STALLED FRONT. THE
ADDITION OF THE SEABREEZE BOUNDARY AND THE OLD OUTFLOW BOUNDARY
SHOULD GIVE PLENTY OF POTENTIAL TRIGGERS FOR STORMS TO DEVELOP.
LAPSE RATES WILL BE PARTICULARLY STEEP UP THROUGH 650 MB...INDUCING
LARGE INITIAL PARCEL ACCELERATION AND A RAPID ERUPTION OF STORMS
ONCE CONVECTIVE TEMPERATURES ARE REACHED. FORECAST POPS TODAY RANGE
FROM 70 PERCENT ACROSS INTERIOR SE NORTH CAROLINA TO 40 PERCENT
ALONG THE SANTEE RIVER...GRADUALLY TAPERING DOWN LATE THIS EVENING
AS CONVECTIVE OVERTURNING STABILIZES THE ATMOSPHERE.
MID AND UPPER LEVEL WINDS WILL BE EXCEEDINGLY WEAK TODAY...5-8 KT AT
850 MB...5-10 KT AT 500 MB...AND AROUND 10 KT AT 300 MB. THIS SHOULD
PROMOTE SINGLE-CELL STORMS WITH VERY LITTLE ORGANIZATION. STORMS
WILL CHOKE ON THEIR OWN COLD OUTFLOW BUT BOUNDARY COLLISIONS SHOULD
EASILY CREATE A NUMBER OF NEW CELLS. VERY SLOW CELL MOTION WILL
PRODUCE A PATCHWORK OF VERY HEAVY RAINFALL AMOUNTS...POSSIBLY 2-3
INCHES IN ISOLATED SPOTS...INTERSPERSED WITH LIGHTER TOTALS. HIGH
WINDS FROM WET MICRO BURSTS WILL BE THE MAIN SEVERE WEATHER THREAT
WITH A POTENTIAL OF ISOLATED HAIL AS WELL. THESE STORMS COULD ALSO
BECOME VERY PROLIFIC LIGHTNING PRODUCERS SINCE THEORETICAL
PARCEL-MINUS-ENVIRONMENTAL TEMPERATURE DIFFERENCES SHOULD REMAIN
LARGE (6-8 DEGREES C) UP THROUGH THE -10 TO -30C LAYER.
HIGH TEMPERATURES SHOULD REACH THE UPPER 80S TO AROUND 90
TODAY...WARMEST ACROSS THE SC PEE DEE REGION. LOWS TONIGHT SHOULD
FALL INTO THE UPPER 60S FOR MOST AREAS.
&&
.SHORT TERM /FRIDAY THROUGH SATURDAY NIGHT/...
AS OF 300 AM THURSDAY...INTERESTING PATTERN FOR THE SHORT TERM...AS
AMPLIFIED AND BLOCKED 5H FLOW FORCES SYSTEMS TO RETROGRADE ALOFT.
TWO LARGE UPPER LOWS...ONE NEARLY STATIONARY ACROSS THE ARKLATEX
REGION...AND ANOTHER RE-STRENGTHENING OVER SOUTHEAST CANADA...WILL
CONTINUE THEIR LOCAL INFLUENCES INTO THE WKND...WITH THE CAROLINAS
REMAINING SANDWICHED BETWEEN THE TWO. ATOP THE ARKLATEX LOW...A
RIDGE OF HIGH PRESSURE BLOSSOMING NEAR THE GREAT LAKES WILL BE
FORCED SOUTHEAST TOWARDS THE AREA ON SATURDAY AS IT...ALMOST
LITERALLY...GETS SQUEEZED OUT BY THE NORTHEAST TROUGH...FORCING THE
ARKLATEX LOW TO RETROGRADE AND WEAKEN ACROSS EAST TEXAS. AT THE
SURFACE...A BACK DOOR TYPE COLD FRONT WILL SINK SLOWLY ACROSS THE
AREA FRIDAY...DROPPING SOUTH LATE SATURDAY...AS ITS MOTION GETS BOTH
ASSISTED (BY NORTHEAST TROUGH) AND IMPEDED (BY UPPER
RIDGE)...CAUSING ITS SLOW PROGRESSION. THIS FRONT WILL BE THE
IMPETUS FOR CONVECTION EACH DAY...AND THE MAIN CHALLENGE FOR TEMPS
AS WELL.
FRIDAY LOOKS TO BE THE MORE ACTIVE...AND WARMER DAY OF THE SHORT
TERM. FRONT WILL BE ROUGHLY BISECTING THE CWA...ALIGNED EAST TO WEST
NEAR THE SC/NC LINE...FRIDAY MORNING. THE AIR MASS IMMEDIATELY
BEHIND THIS FEATURE IS NOT DRASTICALLY DIFFERENT THAN THAT AHEAD OF
IT...SO WHILE TEMPS ACROSS THE NORTHERN HALF OF THE CWA WILL BE
SLIGHTLY COOLER THAN THOSE IN THE SOUTH...STILL EXPECT HIGHS IN THE
LOW/MID 80S NORTH...MID/UPR 80S SOUTH. LOWS FRIDAY NIGHT WILL DROP
TO NEAR CLIMO VALUES...LOW/MID 60S...HIGHEST IN THE SOUTHERN
ZONES.
MORE SIGNIFICANTLY...SHOWERS/TSTMS ARE EXPECTED TO BE WIDESPREAD ON
FRIDAY...AS EVIDENCED BY A LARGE SWATH OF 90% 12-HR SREF PROBS FOR
0.01 INCHES ACROSS THE AREA. THE HIGHEST PROBS ARE ACROSS SC...BUT
THE ENTIRE CWA IS LIKELY TO SEE CONVECTION ON FRIDAY. SBCAPE VALUES
RISE TO AROUND 1500 J/KG SOUTH OF THE FRONT...BUT RAPIDLY FALL OFF
BEHIND IT. A SIMILAR PWAT GRADIENT EXISTS AS WELL...FROM ABOUT 1.9
INCHES WELL SOUTH...TO 1.3 INCHES FAR NORTH...IN A COLUMN
CHARACTERIZED BY AROUND 10 KFT OF WARM CLOUD DEPTH. THIS SETUP
SUPPORTS VERY HEAVY RAIN POTENTIAL...AS EFFICIENT PRECIPITATION
PROCESSES ARE LIKELY DUE TO MODERATELY STRONG UPDRAFTS INTO A DEEPLY
SATURATED COLUMN. ALTHOUGH LAPSE RATES ARE NOT VERY
IMPRESSIVE...CREATING LOW NORMALIZED-CAPE VALUES...THIS HAS BEEN
SHOWN TO FURTHER ENHANCE PRECIPITATION EFFICIENCY...AND THUS HEAVY
RAINFALL WILL BE THE PRIMARY RISK ON FRIDAY...ESPECIALLY NOTING
THE ADDED CAVEAT OF SLOW STORM MOTIONS. AT THE SAME TIME...A MID-
LEVEL IMPULSE IS PROGGED TO ROTATE DOWN WITHIN THE NW
FLOW...MOVING ATOP THE FRONT DURING THE LATE AFTN...WHICH WILL
ONLY ACT TO ENHANCE COVERAGE AND INTENSITY OF SHOWERS/STORMS. THIS
SUGGESTS THE STRONGEST CONVECTION WILL BE IN THE SOUTHERN THIRD OF
THE CWA...AND HIGHEST POP...LIKELY...WILL BE SHOWN
THERE...TRENDING DOWN TO CHC IN THE NORTH. WITH THIS SETUP IN
PLACE...AND THURSDAY EXPECTED TO BE WET AS WELL...LOCALIZED
FLOODING MAY BECOME A CONCERN...ESPECIALLY ACROSS SOUTH CAROLINA
ZONES...AND THIS WILL NEED TO BE MONITORED CLOSELY DURING THE NEXT
DAY.
A QUIETER DAY SATURDAY...BUT WITH THE FRONT STILL SLOWLY SINKING
SOUTH...SOME DIURNALLY ENHANCED SHOWERS/TSTMS ARE
POSSIBLE...ESPECIALLY IN THE PEE DEE REGION AND ALONG THE SOUTH
SANTEE RIVER. PROFILES SHOW PRETTY QUICK DRYING FROM NORTH TO SOUTH
THROUGH THE DAY...SO BEST PRECIP CHANCES WILL BE EARLY IN THE
AFTN...WITH POP DROPPING TO SILENT BY THE EVENING. TEMPS WILL BE
COOLER BY A FEW DEGREES BEHIND THE FRONT...LOW/MID 80S AREA-WIDE
WITH LOWS POTENTIALLY FALLING BELOW 60 IN THE FAR NORTH SATURDAY
NIGHT...LOW 60S ELSEWHERE.
&&
.LONG TERM /SUNDAY THROUGH THURSDAY/...
AS OF 300 AM THURSDAY...UPPER RIDGE DROPS ACROSS THE AREA EARLY IN
THE PERIOD...BEFORE FLATTENING INTO THE MIDDLE OF NEXT WEEK. AT THE
SURFACE...COOL HIGH PRESSURE DROPS SOUTH OUT OF NEW ENGLAND ON
SUNDAY BEFORE MOVING OVERHEAD EARLY NEXT WEEK AND THEN OFFSHORE LATE
IN THE EXTENDED. THIS PATTERN PRODUCES MOSTLY QUIET WEATHER WITH
SEASONABLE TO SLIGHTLY BELOW CLIMO TEMPS SUN/MON AND WITH MUCH
DECREASED HUMIDITY. ALTHOUGH THE UPPER PATTERN FLATTENS NEXT
WEEK...THE HIGH PRESSURE MOVING OFFSHORE WILL BEGIN TO DRIVE
WARM/MOIST RETURN FLOW BACK INTO THE CAROLINAS TUE/WED. WHILE TEMPS
ARE NOT EXPECTED TO REACH WELL ABOVE NORMAL LEVELS LIKE WE SAW
FREQUENTLY IN MAY...SLIGHTLY ABOVE CLIMO VALUES ARE EXPECTED FOR THE
MIDDLE OF NEXT WEEK...ALONG WITH SLOWLY INCREASING DIURNAL TSTM
CHANCES.
&&
.AVIATION /18Z THURSDAY THROUGH TUESDAY/...
AS OF 18Z...POSSIBLE PERIODS OF MVFR DUE TO FOG/REDUCED VSBYS IN
ISOLATED TO SCATTERED CONVECTION LATER TODAY AND TONIGHT
POSSIBLE...AS WELL AS MVFR FOG LATE OVERNIGHT INTO THE EARLY
MORNING HOURS. OTHERWISE EXPECT VFR.
VFR PREVAILS THIS AFTERNOON WITH VARYING FEW/SCT/BKN CLOUD
HEIGHTS...LOW TO HIGH LEVEL AND LIGHT AND VARIABLE WINDS. AN
APPROACHING COLD FRONT FROM THE NORTH WILL MOVE DOWN INTO THE AREA
TODAY...AND WITH AN OVERALL FAVORABLE ENVIRONMENT...ANTICIPATE
INCREASING CHANCES FOR SHOWERS AND THUNDERSTORMS THIS AFTERNOON
AND INTO THE EVENING HOURS. REDUCED RESTRICTIONS WILL BE POSSIBLE
IN ANY HEAVY DOWNPOUR OR PATCHY FOG. WEST WINDS THIS MORNING WILL
SHIFT TO THE EAST-NORTHEAST BY THIS AFTERNOON DEPENDING ON THE
LOCATION OF THE AFOREMENTIONED FRONTAL BOUNDARY. BUT OVERALL WINDS
WILL BE AOB 10 KTS. INTO THE OVERNIGHT HOURS...ACTIVITY WILL TAPER
OFF WITH LIGHT WINDS...LOW CIGS AND PATCHY FOG LIKELY...POSSIBLY
CREATING MVFR/IFR CONDITIONS THROUGH MORNING. BY FRIDAY
MORNING...EXPECT VFR TO PREVAIL WITH LIGHT WINDS.
EXTENDED OUTLOOK...SCATTERED SHOWERS/TSTMS WITH BRIEF PERIODS OF
SUB-VFR CONDITIONS EXPECTED THROUGH FRIDAY...MAINLY IN THE
AFTERNOON AND EARLY EVENING HOURS. VFR SATURDAY THROUGH MONDAY.
&&
.MARINE...
NEAR TERM /THROUGH TONIGHT/...
AS OF 1:30 PM THURSDAY...COLD FRONT NOW DROPPING SOUTH ACROSS OUR
NC WATERS WITH WINDS TURNING NE NORTH OF CAPE FEAR. NO CHANGES
TO THE FORECAST WITH THE LATEST UPDATE. PREVIOUS DISCUSSION
FOLLOWS:
A COLD FRONT RECENTLY MOVED SOUTH OF CAPE LOOKOUT AND SHOULD REACH
SOUTHEASTERN NORTH CAROLINA NORTH OF CAPE FEAR BEFORE NOON. THE
FRONT SHOULD THEN STALL AND TEMPORARILY BECOME DIFFUSE WITH THE
DEVELOPING AFTERNOON SEABREEZE CIRCULATION. THIS SHOULD LEAD TO A
VARIETY OF WIND DIRECTIONS ACROSS THE COASTAL WATERS: MAINLY
NORTHEAST NORTH OF CAPE FEAR...AND MAINLY SOUTHWEST SOUTH OF CAPE
FEAR...BUT WITH THE SEABREEZE DETERMINING THE EVENTUAL DIRECTION.
FAIRLY WIDESPREAD THUNDERSTORMS SHOULD DEVELOP INLAND THIS
AFTERNOON. VERY SLOW MOVEMENT MEANS MOST OF THESE STORM CELLS WILL
REMAIN INLAND ON THE WEST SIDE OF THE SEABREEZE...HOWEVER A FEW
COULD DRIFT OUT PAST THE BEACHES INTO THE NEARSHORE WATERS. ANY
STORMS WILL BE ACCOMPANIED BY GUSTY WINDS AND A GOOD DEAL OF
LIGHTNING.
THE FRONT SHOULD SINK SOUTHWARD INTO THE MYRTLE BEACH/MURRELLS INLET
AREA OVERNIGHT. AS INLAND THUNDERSTORMS DIE DOWN DURING THE EVENING
THERE IS THE POTENTIAL THE CONVECTIVE RISK COULD SHIFT OFFSHORE.
SEAS CURRENTLY AROUND 2 FEET SHOULD CHANGE LITTLE THROUGH TONIGHT
WITH MAINLY LIGHT WINDS EITHER SIDE OF THE FRONT. OBVIOUSLY NEAR ANY
THUNDERSTORMS WINDS AND SEAS COULD TEMPORARILY BUILD QUITE A BIT
HIGHER.
SHORT TERM /THURSDAY THROUGH FRIDAY NIGHT/...
AS OF 300 AM THURSDAY...SLOW MOVING BACK DOOR COLD FRONT WILL DROP
SOUTH ACROSS THE WATERS...BUT WILL TAKE UNTIL SATURDAY MORNING TO
MAKE IT ALL THE WAY SOUTH OF THE AREA. THIS WILL CREATE LIGHT AND
VARIABLE WINDS ON FRIDAY...FROM THE NE ON THE NORTH SIDE OF THIS
FRONT...AND THE S/SE TO THE SOUTH. BY SATURDAY...ALL WINDS WILL
BECOME N/NE WITH A WEAK SURGE CAUSING AN INCREASE IN SPEED TO 10-15
KTS. SEAS FRIDAY WILL BE PRIMARILY 1-2 FT...BUT WILL START TO RISE
TOWARDS 3 FT FRIDAY NIGHT ACROSS THE NC WATERS. SATURDAY SEAS WILL
BE DRIVEN BY THE ENHANCED NE WINDS...BECOMING 2-4 FT ALL WATERS.
LONG TERM /SATURDAY THROUGH MONDAY/...
AS OF 300 AM THURSDAY... HIGH PRESSURE BUILDING DOWN THE COAST WILL
DRIVE A PINCHED GRADIENT OVER THE WATERS ON SUNDAY...WITH NE WINDS
OF AROUND 15 KTS COMMON THROUGH THE DAY. THIS HIGH WILL BUILD DOWN
ACROSS THE WATERS SUNDAY NIGHT...THEN DRIFT OFFSHORE
MONDAY...CAUSING WINDS TO WEAKEN AND VEER SLOWLY...TO THE SW AT 5-10
KTS BY THE END OF THE PERIOD. SEAS OF 2-4 FT ARE EXPECTED SUNDAY
WITH A NE WIND CHOP PREDOMINANT WITHIN THE WAVE SPECTRUM. WAVE
HEIGHTS FALL TO 2-3 FT MONDAY AS THE WINDS EASE.
&&
.ILM WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
NC...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...TRA/JDW
NEAR TERM...REK/TRA
SHORT TERM...JDW
LONG TERM...JDW
AVIATION...SGL
MARINE...REK/TRA/JDW
AREA FORECAST DISCUSSION
NWS GREENVILLE-SPARTANBURG SC
446 PM EDT THU MAY 29 2014
.SYNOPSIS...
A BACKDOOR COLD FRONT WILL SLOWLY CROSS THE FORECAST AREA FROM THE
NORTHEAST THROUGH FRIDAY NIGHT. HIGH PRESSURE WILL BUILD IN FROM THE
NORTHEAST THIS WEEKEND...AND MOVE OFFSHORE EARLY NEXT WEEK.
&&
.NEAR TERM /THROUGH FRIDAY/...
430 PM UPDATE...FOR THE REMAINDER OF THE AFTERNOON...CONVECTION
SHOULD CONTINUE TO BLOSSOM. CURRENT ACTIVITY IS MAINLY IN CLUSTERS
ALONG OLD OUTFLOW BOUNDARIES...PARTICULARLY ONE LINEAR CLUSTER
HAVING PROPAGATED IN THIS WAY OVER THE TUGALOO/SAVANNAH RIVERS.
ANOTHER CLUSTER IS DEVELOPING ALONG THE BACKDOOR FRONT JUST NE OF
CHARLOTTE. IN GENERAL THE LATEST HRRR SEEMS TO BE DOING A REASONABLY
GOOD JOB AND ALLOWS THE CURRENT ACTIVITY TO DIE DOWN DIURNALLY OVER
THE WRN HALF OF THE FA...BUT INCREASING COVERAGE OVER THE NC
PIEDMONT ALONG THE FRONT. HAVE MAINTAINED THIS IN THE FCST. STEERING
FLOW IS RATHER WEAK...SO STORMS WILL MOVE ONLY SLOWLY. FLASH
FLOODING COULD BE AN ISSUE WITH THE SLOW MOVEMENT OF THE STORMS AND
THE RELATIVELY DEEP MOISTURE. WE MAY SEE A FEW PULSE-TYPE SEVERE
THUNDERSTORMS AS BUOYANCY LOOKS SUFFICIENT AND GENERALLY CLIMBING UP
ABOVE 2000 J/KG...AND DCAPE HAS NOW BECOME INTERESTING /600-900 J/
SOUTH OF THE SRN NC BORDER.
OVER THE NEXT 24 HOURS...THE MAIN CONCERN WILL BE THE FRONTAL ZONE
DROPPING DOWN FROM THE NORTH. A SURFACE REFLECTION ALREADY SHOWS IN
THE CAPE ANALYSIS NUDGING INTO THE NW PIEDMONT...WITH LOW CLOUDINESS
AND STABLE AIR IN N CENTRAL NC. A SHORT WAVE DROPPING DOWN INTO THE
UPPER TROF OFF THE EAST COAST WILL CONTINUE TO DRIVE THIS BOUNDARY
FARTHER SOUTH AND EAST THIS EVENING. THE MODELS DO NOT REALLY SHOW
MUCH IN THE WAY OF LOW LEVEL FORCING BUT THIS COULD BE MASKED BY THE
DIURNAL CONVERGENCE TOWARD THE MTNS. IT STANDS TO REASON THAT THE
BOUNDARY MAY PROVIDE THE FOCUS FOR CONVECTION WELL INTO THE
NIGHTTIME HOURS. THERE IS SOME CONCERN FOR FLASH FLOOD POTENTIAL
OVER THE NC BLUE RIDGE AND FOOTHILLS IF THE BOUNDARY MOVES FAR
ENOUGH SOUTH TO DEVELOP A LOW LEVEL EASTERLY FLOW THAT COULD ANCHOR
STORMS NEAR THE BLUE RIDGE...BUT NOT ENOUGH CONCERN TO ENTERTAIN A
WATCH. EXPECT A DIURNAL REDUCTION IN STORM COVERAGE AFTER MIDNIGHT
IN SPITE OF THE BOUNDARY...SO SOME OF THE LATEST SREF WAS BLENDED
INTO THE POP. ON FRIDAY...SHOWERS AND STORMS SHOULD DEVELOP YET
AGAIN ACROSS THE ENTIRE FCST AREA...BUT WE MIGHT BE COVERED WITH A
LOW CLOUD CEILING BANKED UP AGAINST THE BLUE RIDGE THAT WILL CUT
DOWN ON THE POTENTIAL FOR SEVERE STORMS. TEMPS SHOULD BE A BIT
COOLER WITH THE ADDITIONAL CLOUD COVER AND EASTERLY FLOW DEVELOPING.
&&
.SHORT TERM /FRIDAY NIGHT THROUGH SUNDAY/...
AT 215 PM EDT THURSDAY...ON FRIDAY NIGHT AN UPPER RIDGE OVER THE
NORTHERN PLAINS WILL MOVE SOUTHEAST BETWEEN A CLOSED LOW OVER LA AND
AND UPPER TROUGH OFF THE EAST COAST...REACHING THE SOUTHERN
APPALACHIANS. THE RIDGE CENTER WILL MOVE OVER THE OH RIVER VALLEY ON
SATURDAY...AND OVER GA ON SUNDAY.
A BACK DOOR COLD FRONT WILL DRIFT VERY SLOWLY SOUTH ACROSS SC ON
FRIDAY NIGHT...AND ACROSS THE SAVANNAH RIVER VALLEY ON SATURDAY.
MODEL SOUNDINGS SHOW ELEVATED INSTABILITY VERY SLOWLY DECREASING
ALONG THE BOUNDARY ON FRIDAY NIGHT...AND INCREASING AGAIN ON
SATURDAY...MAINTAINING A THREAT OF CONVECTION AND HEAVY RAINFALL. ON
SATURDAY NIGHT THE FRONT MOVES SOUTHWEST OF OUR AREA...BUT LINGERING
LOW LEVEL MOISTURE AND AN EASTERLY UPSLOPE COMPONENT WILL SUPPORT A
CHANCE PRECIPITATION ALONG THE SOUTHERN BLUE RIDGE ESCARPMENT. DRIER
AIR WORKING INTO THE AREA FROM THE NW ON SUNDAY WILL REDUCE THE
CHANCE OF PRECIPITATION...BUT THE MODEL SUGGEST THAT MOISTURE BANKED
UP AGAINST THE SOUTHERN BLUE RIDGE WILL PERSIST...AND SMALL POPS
WILL BE CARRIED THERE AGAIN.
TEMPERATURES WILL RUN ABOVE NORMAL WITH RISING HEIGHTS ALOFT...UNTIL
COOLER AIR BEHIND THE FRONT WORKS INTO THE AREA ON SUNDAY.
&&
.LONG TERM /SUNDAY NIGHT THROUGH THURSDAY/...
AT 215 PM EDT THURSDAY...ON MONDAY AN UPPER RIDGE WILL EXTEND FROM
FL TO THE EASTERN GREAT LAKES...WHILE A CLOSED UPPER LOW WILL BE
OVER THE WESTERN ATLANTIC AND AN UPPER TROUGH WILL BE OVER THE WEST
COAST. THE UPPER RIDGE PROGRESS TO THE EAST COAST BY TUESDAY...WHILE
A SHORTWAVE MOVES ACROSS THE GREAT LAKES AREA. THE PATTERN
DEAMPLIFIES BY WEDNESDAY...LEADING TO A LARGELY ZONAL FLOW ACROSS
THE NATION...AND WEAK FLAT RIDGING OVER THE SOUTHEAST...A PATTERN
THAT PERSISTS INTO THURSDAY.
SURFACE HIGH PRESSURE WILL BE CENTERED NEAR THE COASTAL VA AND NC ON
MONDAY...AND ALTHOUGH GULF INFLOW ON THE WEST SIDE OF THIS RIDGE
WILL BE FOCUSED OVER THE MS...TN AND OH VALLEYS...THE MODELS
INDICATE MOISTURE OVER THE SOUTHERN APPALACHIANS...WITH UPSLOPE FLOW
AND INCREASING INSTABILITY SUPPORTING DIURNALLY DRIVEN CONVECTION.
AS THE SURFACE HIGH DRIFTS SE AND OFFSHORE FROM TUESDAY THROUGH
THURSDAY...GULF INFLOW WEAKENS...BUT SPREADS EAST...COVERING NE GA
AND THE WESTERN CAROLINAS. UPSLOPE FLOW INTO ELEVATED TERRAIN WILL
BE RATHER WEAK...BUT ENOUGH TO SUPPORT THE BEST CHANCES OF
CONVECTION REMAINING ALONG THE BLUE RIDGE...EVEN AS CONVECTIVE
CHANCES INCREASE TO THE EAST.
TEMPERATURES WILL RISE FROM NEAR NORMAL VALUES...TO ABOVE NORMAL...
EVEN AS HEIGHTS FALL ALOFT...AS COOL NE FLOW VEERS TO THE SW...
AND WARM ADVECTION ENSUES.
&&
.AVIATION /21Z THURSDAY THROUGH TUESDAY/...
AT KCLT...FOR THE REST OF THE DAYLIGHT HOURS...VFR CONDITIONS ARE
EXPECTED OUTSIDE OF THUNDERSTORMS. CLOUD BASES SHOULD BE AROUND
045-050. KEPT THE LOW CLOUDS FEW OR SCT FOR THE INITIAL PERIOD BUT
THERE COULD EASILY BE A TEMPORARY CEILING AT THAT LEVEL. THIS
POSSIBILITY WAS LEFT OUT FOR BREVITY. THE CONVECTION ALLOWING MODELS
ARE STILL GOING FOR A WINDOW OF THUNDERSTORM ACTIVITY DURING THE
LATE AFTERNOON AND EARLY EVENING HOURS...SO THE TEMPO FOR
THUNDERSTORMS WAS KEPT. THE STORMS COULD LINGER THROUGH THE EVENING
AND EARLY MORNING HOURS AS A BACK DOOR COLD FRONT DROPS INTO THE
REGION. INCLUDING A MENTION OF VCSH FOR NOW BUT EXPECT A TEMPO TO BE
ADDED AGAIN AFTER THE FIRST TEMPO EXPIRES. FRONT WILL BRING AN MVFR
CEILING INTO THE PIEDMONT FOR THE HOURS AROUND DAYBREAK. THE LOW
CLOUD CEILING SHOULD LIFT AND SCATTER BY MID MORNING FRIDAY. SOME
DETAIL WAS LEFT OUT OF THE TAF AFTER SUNRISE FRIDAY.
ELSEWHERE...EXPECT MAINLY AFTN AND EVENING CONVECTION WILL FOCUS
ALONG AN APPROACHING BACKDOOR COLD FRONT...WITH TSRA CHANCES HIGHER
FROM KAVL TO KHKY THAN FARTHER S AT THE UPSTATE SC SITES. SHOWERS
AND ISOLD TO SCT TSTMS MAY LINGER THROUGH THE NIGHT...ESPECIALLY
NEAR THE ERN SLOPES OF THE MTNS FROM KAVL TO NEAR KGSP. SFC WINDS
WILL ADJUST TO NRLY TO NELY WITH THE ARRIVAL OF THE FRONT TODAY AT
THE NC SITES...WHILE CONTINUED SW FLOW IS LIKELY AT THE UPSTATE
SITES BEFORE BECOMING LIGHT AND VARIABLE THIS EVENING.
OUTLOOK...ALTHOUGH GRADUAL DRYING WILL DEVELOP FROM THE NE OVER THE
WEEKEND INTO EARLY NEXT WEEK...CONTINUED BOUNDARY LAYER MOISTURE
WILL PRODUCE ISOLATED TO SCATTERED DIURNAL CONVECTION EACH
DAY...WITH MORNING RESTRICTIONS POSSIBLE.
CONFIDENCE TABLE...
20-02Z 02-08Z 08-14Z 14-20Z
KCLT HIGH 100% HIGH 92% MED 64% HIGH 86%
KGSP HIGH 100% HIGH 100% LOW 45% HIGH 91%
KAVL HIGH 100% MED 71% HIGH 83% HIGH 86%
KHKY HIGH 100% MED 77% MED 67% MED 68%
KGMU HIGH 100% HIGH 100% LOW 56% HIGH 91%
KAND HIGH 100% HIGH 94% HIGH 86% HIGH 91%
THE PERCENTAGE REFLECTS THE NUMBER OF GUIDANCE MEMBERS AGREEING
WITH THE SCHEDULED TAF ISSUANCE FLIGHT RULE CATEGORY. COMPLETE
HOURLY EXPERIMENTAL AVIATION FORECAST CONSISTENCY TABLES AND ENSEMBLE
FORECASTS ARE AVAILABLE AT THE FOLLOWING LINK: (MUST BE LOWER CASE)
WWW.WEATHER.GOV/GSP/AVIATION_TABLES
&&
.GSP WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
NC...NONE.
SC...NONE.
&&
$$
SYNOPSIS...JAT
NEAR TERM...PM/WIMBERLEY
SHORT TERM...JAT
LONG TERM...JAT
AVIATION...PM/WIMBERLEY
AREA FORECAST DISCUSSION
NWS MEMPHIS TN
1226 PM CDT THU MAY 29 2014
.DISCUSSION... /ISSUED 1029 AM CDT THU MAY 29 2014/
UPDATE...
AN UPPER LEVEL LOW PRESSURE SYSTEM WILL CONTINUE TO BRING
NUMEROUS SHOWERS WITH A FEW EMBEDDED THUNDERSTORMS TO THE MIDSOUTH
TODAY. LATEST HRRR SHOWS A BAND MOVING NORTHWARD FROM CENTRAL
MISSISSIPPI INTO NORTH MISSISSIPPI...THE MEMPHIS METRO AREA...AND
EVENTUALLY SPREADING INTO NORTHEAST ARKANSAS BETWEEN 1-4 PM. WILL UPDATE
TO EXPAND 80 POPS NORTHWARD TO COVER THIS AREA. WILL ALSO UPDATE
TO LOWER TEMPS DUE TO CLOUD COVER AND SHOWER ACTIVITY. UPDATE WILL
BE OUT SHORTLY.
KRM
DISCUSSION... /ISSUED 301 AM CDT THU MAY 29 2014/
CURRENT UPPER LOW WAS CENTERED OVER SOUTH CENTRAL ARKANSAS WITH
MODELS SUGGESTING THIS AS ITS CLOSEST POSITION TO THE MIDSOUTH
BEFORE SLOWLY DRIFTING SOUTHWESTWARD. ON THE SURFACE WINDS HAVE
BACKED TO A MORE EASTERLY COMPONENT AS AN INDUCED SURFACE LOW HAS
DEVELOPED IN THE SAME AREA. AS OF 3AM TEMPERATURES WERE BETWEEN
65F AND 70F...AND RADAR WAS SHOWING SCATTERED LIGHT SHOWERS
DRIFTING NORTHWARD OVER THE SOUTHWEST DELTA COUNTIES.
FOR TODAY AND TOMORROW...THE REGION WILL REMAIN INFLUENCED BY THE
CLOSED LOW WITH SCATTERED TO NUMEROUS SHOWERS ANTICIPATED DURING
THE HEAT OF THE DAY...AND LESS COVERAGE AT NIGHT. AGREED MODEL
CONSISTENCY POINTS TO THE REGION SOUTH AND WEST OF MEMPHIS WITH
THE GREATEST PROBABILITY OF PRECIPITATION...WHERE A WEAK INDUCED
INVERTED SURFACE TROUGH WILL FORM. THE HIGHEST QPF AMOUNTS WILL
BE OVER THIS AREA...WITH PERHAPS UP TO AN INCH AND HALF THROUGH
FRIDAY AFTERNOON. SIGNIFICANT CLOUD COVER WILL KEEP TEMPERATURES
BELOW NORMAL TODAY...AND CLOSER TO NORMAL TOMORROW. THIS...IN
ADDITION TO THE ONGOING MOIST ADIABATIC LAPSE RATES OFF FORECAST
SOUNDINGS SUGGESTS A REDUCTION IN THUNDERSTORM COVERAGE. A FEW
MORE BREAKS IN THE CLOUD COVER IS ANTICIPATED
TOMORROW...ESPECIALLY OVER THE NORTHERN HALF OF THE CWA AS THE LOW
CENTER MOVES TO NEAR LAKE SABINE IN WESTERN LOUISIANA. THEREFORE
THUNDERSTORM COVERAGE WILL REBOUND BACK...AND NORTH MISSISSIPPI
WILL STILL RUN THE GREATEST RISK FOR RAIN.
SATURDAY AND SUNDAY...NOT MUCH CHANGE WAS NEEDED WITH THE FORECAST
THIS PERIOD...WITH ONLY A SLIGHT INCREASE IN POPS AND A DEGREE
COOLER IN TEMPERATURES. THE REGION WILL REMAIN MOIST AS THE UPPER
LOW OPENS AND A WEAK SHEAR AXIS HANGS ALONG THE MISSISSIPPI RIVER.
LESS CLOUD COVER WILL ALLOW TEMPERATURES TO SHIFT BACK CLOSER TO
90F...WHICH MAY TRIGGER AN ISOLATED STRONG STORM DURING THE
AFTERNOON HOURS.
MONDAY THROUGH WEDNESDAY NIGHT...A SERIES OF WEAK SHORTWAVES WILL
CROSS THE ROCKIES AND THE MIDWEST WITH THE MIDSOUTH SHIFTING FROM
A LIGHT SOUTHEASTERLY/SOUTHERLY UPPER FLOW TO MORE WESTERLY. THE
ECMWF IS A BIT MORE BULLISH WITH QPF AMOUNTS OVER THE AREA FROM
FRONTAL MCS GENERATION IN THE MIDWEST...WHILE THE GFS KEEPS THE
WEAK FRONT AND CONVECTIVE CONCENTRATION IN THE CORN BELT. FOR NOW
HAVE KEPT RAIN CHANCES MORE CONSERVATIVE AND DIURNAL. TEMPERATURES
NEXT WEEK WILL REMAIN NEAR 90F FOR HIGHS AND 70F FOR LOWS...WITH A
SLIGHT SOUTHERLY BREEZE PROVIDING SOME RELIEF.
JAB
&&
.AVIATION...
18Z TAF CYCLE (29/18Z-30/18Z)
AN UPPER LEVEL LOW PRESSURE SYSTEM OVER SOUTHERN AR WILL DRIFT SLOWLY
TO THE SW INTO NW LA-ERN TX BY 30/18Z AND CONTINUE UNSETTLED WEATHER
ACROSS THE MIDSOUTH THRU FRI. SCATTERED SHOWERS WILL CONTINUE TO
OCCUR THRU THE PERIOD...WITH BEST CHANCES FOR TS IN THE AFTERNOON
TO EARLY EVENING HOURS. DID TAKE VCSH OUT OF MKL/TUP LATER TONIGHT
AS COVERAGE SHOULD DIMINISH SOME AS THE LOW MOVES FURTHER FROM
THESE LOCATIONS. WINDS REMAIN ESE-SE THRU THE PERIOD...INCREASING
SLIGHTLY DURING THE LATE MORNING TO AFTERNOON HOURS. CIGS
GENERALLY EXPECTED TO INCREASE TO VFR BY EARLY-MID AFTERNOON WITH
MVFR CIG/VIS STILL POSS IN AREAS OF SHRA/TS. CIGS EXPECTED TO
AGAIN DECREASE BY MIDNIGHT OR SHORTLY THEREAFTER...WITH SOME
PATCHY IFR POSS AT ALL LOCATIONS...BEST CHANCES BETWEEN 08-13Z.
BROUGHT BACK MENTION OF VCTS TOMORROW AT 17Z CONTINUING DIURNAL
TRENDS WITH THE UPPER-LEVEL SYSTEM TO THE SOUTHWEST.
NGU
&&
.MEG WATCHES/WARNINGS/ADVISORIES...
AR...NONE.
MO...NONE.
MS...NONE.
TN...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS BLACKSBURG VA
140 PM EDT THU MAY 29 2014
.SYNOPSIS...
LOW PRESSURE WAS IN SOUTHERN PENNSYLVANIA WITH A COLD FRONT
EXTENDING INTO NORTHEAST NORTH CAROLINA. THIS FRONT WILL MOVE
SOUTH TODAY AND STALL IN THE CAROLINAS TONIGHT. HIGH PRESSURE WILL
BUILD IN OVER THE EASTERN UNITED STATES BY THE WEEKEND WITH
SLIGHTLY COOLER AND DRIER AIR FOR SATURDAY AND SUNDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 921 AM EDT THURSDAY...
BACKDOOR COLD FRONT...HIGHLIGHTED NICELY BY MSAS ANALYSIS OF
LIFTED INDEX AND PRESSURE CHANGES...PUSHING INTO EASTERN PORTIONS
OF FORECAST AREA THIS MORNING. KFCX 88D SHOWED A FEW SHOWERS
MOVING EAST ACROSS THE NORTH. SATELLITE IMAGES INDICATED SUNSHINE
IN THE WEST WITH LOW CLOUDS ADVANCING WESTWARD TOWARDS BLUE RIDGE.
SFC OBS REPORT THAT IFR CLOUDS HAVE REACH LYH AND DAN THIS
MORNING. OUTSIDE THE LOW CLOUDS...TEMPERATURES HAVE CLIMB QUICKLY
THIS MORNING. MODIFIED TEMPERATURES AND HIGHS UP AS FEW DEGREES
WHERE READINGS ARE WARMER WITH ADDITIONAL SUNSHINE. STILL LOOKS
LIKE MOST LOCATIONS WILL BE CLOUDY BY 18Z THIS AFTERNOON. THE
COMBINATION OF LOW LEVEL CONVERGENCE ALONG THE SURFACE FRONT AND
THE LIFT FROM THE PASSING SHORT WAVE WILL RESULT IN SCATTERED TO
NUMEROUS SHOWERS AND THUNDERSTORMS THIS AFTERNOON AND EVENING. THE
LOCAL RNK WRFARW AND HRRR SUGGEST THAT MOST OF THE CONVECTION
STARTS AFTER 18Z THIS AFTERNOON...WITH NUMEROUS COVERAGE BY 00Z
THIS EVENING. MORE CHANGES LATER THIS MORNING...
AS OF 400 AM EDT THURSDAY...
500 MB PATTERN AMPLIFIES WITH A TROF ALONG THE EAST COAST DURING
THIS TIME FRAME. A SHORT WAVE AND ASSOCIATED JET STREAK CROSS FROM
THE OHIO VALLEY INTO NORTH CAROLINA BY MIDNIGHT.
MSAS ANALYSIS OF LIFTED INDEX AND PRESSURE CHANGES SHOWED FRONT WAS
JUST INTO THE EASTERN COUNTY WARNING AREA AT 3AM. MODELS BRING THE
BOUNDARY AS FAR WEST AS ROANOKE DURING THE DAY THEN EXPECTING THE
STABLE AIR TO ADVANCE DOWN THE EAST SLOPES OF THE BLUE
RIDGE...ALTHOUGH VERY SHALLOW OVERNIGHT. MOISTURE ABOVE 700MB GETS
PUSHED TO THE FAR SOUTHWEST COUNTIES OF THE FORECAST AREA BY
MORNING. BUT STILL AMPLE LOW LEVEL MOISTURE THROUGH TONIGHT.
THE COMBINATION OF LOW LEVEL CONVERGENCE ALONG THE SURFACE FRONT AND
THE LIFT FROM THE PASSING SHORT WAVE WILL RESULT IN SCATTERED TO
NUMEROUS SHOWERS THIS AFTERNOON AND EVENING. THE AIR MASS WEST OF
THE BOUNDARY WILL STILL BE UNSTABLE ENOUGH FOR THUNDERSTORMS. BUFKIT
FOR ROANOKE WAS ALSO SHOWING SUPPORT FOR ELEVATED CONVECTION TODAY.
CLOUDS...PRECIPITATION AND COOLER AIR MASS BEHIND THE FRONT WILL
LEAD TO COOLER MAXIMUM TEMPERATURES THAN PAST FEW DAYS IN THE EAST.
WESTERN PARTS OF THE COUNTY WARNING AREA THAT STILL GET ENOUGH SUN
WILL AGAIN REACH THE 80S FOR HIGHS. USED AN NON-DIURNAL
TEMPERATURES CURVE FOR TODAY AND STAYED CLOSE TO MET GUIDANCE FOR
MAXIMUM TEMPERATURES. ALSO USED SLIGHTLY COOLER MET FOR LOWS
TONIGHT.
&&
.SHORT TERM /FRIDAY THROUGH SUNDAY NIGHT/...
AS OF 400 AM EDT THURSDAY...
AN ABNORMAL PATTERN FOR LATE MAY...WITH A DEVELOPING REX BLOCK OVER
THE MISSISSIPPI RIVER VALLEY...AND A DEEPENING UPPER TROUGH OVER NEW
ENGLAND. VEERING THE EASTERLY FLOW TO THE S AND SW WILL BE A VERY
SLOW PROCESS...UNTIL THE NEW ENGLAND TROUGH FINALLY MOVES OFF THE
COAST AND THE UPPER RIDGE CLOSES OFF OVER THE SOUTHEAST BY MONDAY.
CONTINUED WHAT HAS BEEN A NIGHTLY TREND OF LOWERING MAX T JUST ABOUT
EACH DAY...ESPECIALLY BELOW THE MEX GUIDANCE WHICH JUST CAN`T HANDLE
THIS ODD ARRANGEMENT OF UPPER HIGHS AND LOWS. HIGHS TEMPS THROUGH
THIS PERIOD MAY FALL BELOW NORMAL...SAVE EXTREME SW VA AND SE WEST
VA. STILL SOME CLASHING OF AIRMASSES AND SURFACE CONVERGENCE KEEPS
SHOWERS/STORMS IN THE FORECAST THROUGH NW NC AND EXTREME SW VA ON
FRIDAY. ANOTHER STRONGER SURFACE HIGH ROLLING ACROSS THE LAKES AND
INTO NEW ENGLAND BY SUNDAY...WILL LIKELY KEEP ANY SHOWER
DEVELOPMENT SUPPRESSED TO NW NC...IF AT ALL SATURDAY AND SUNDAY.
MODELS HINTING AT SOME DRIZZLE/FOG/LIGHT RAIN SHOWERS BOTH FRIDAY
AND SATURDAY NIGHT WITH EASTERLY UPSLOPE FLOW ALONG THE BLUE
RIDGE. ALSO...CLOUDS WILL PROBABLY FILL BACK IN DURING THE
OVERNIGHTS...AS AFTERNOON MIXING ENDS.
&&
.LONG TERM /MONDAY THROUGH WEDNESDAY/...
AS OF 1245 PM EDT WEDNESDAY...
GOING TO BE HEADING BACK TO SUMMER TEMPS EARLY NEXT WEEK AS UPPER
RIDGE SITUATES ITSELF OVER THE WRN SIDE OF THE APPALACHIANS. BY
MIDWEEK...MODELS BREAK DOWN THE UPPER RIDGE AS TROUGH DIGS ACROSS
SRN CANADA. AT THE SFC...HIGH PRESSURE WORKS FROM THE MID ATLANTIC
TO THE SOUTHEAST COAST.
THE PATTERN SUGGESTS NO ORGANIZED SYSTEMS TO AFFECT US...BUT WILL
HAVE TO WATCH UPSTREAM ESPECIALLY TUE-WED AS THE 5H FLOW FLATTENS
FOR FASTER MOVING SHORTWAVES. OVERALL WILL BE TYPICAL SUMMER DIURNAL
RANGE IN SHRA/TSRA THREAT...WITH BEST CHANCES IN THE MOUNTAINS
ESPECIALLY TUE-WED. A LEE TROUGH SETS UP AS WELL OVER THE PIEDMONT
WHICH COULD AID IN STORM DEVELOPMENT.
FOR NOW KEEPING IN POPS IN THE CHANCE RANGE...WITH SUNDAY LOOKING
DRY.
&&
.AVIATION /18Z THURSDAY THROUGH TUESDAY/...
AS OF 135 PM EDT THURSDAY...
MULTIPLE CHANGES IN WEATHER CONDITIONS ARE EXPECTED THIS AFTERNOON
INTO TONIGHT. CEILINGS HAVE LOWERED TO IFR/LIFR BEHIND THE
FRONT...INCLUDING AT KLYH AND KDAN. EXPECT ONLY LIMITED
IMPROVEMENT THIS AFTERNOON INTO TONIGHT...MAYBE TO MVFR.
A SHORT WAVE TRACKING OUT OF THE OHIO VALLEY WILL CROSS THE
REGION AND INTERACT WITH THE FRONT...LEADING TO NUMEROUS SHOWERS
AND SCATTERED THUNDERSTORMS. ONCE THIS FEATURE PASSES TO THE
SOUTHEAST...MUCH OF THE PRECIPITATION WILL BE LIMITED TO THE
EASTERN SLOPES OF THE BLUE RIDGE...WITH LIGHT RAIN OR DRIZZLE.
THERE MAY BE A BRIEF PERIOD OF VFR CEILINGS AND VISIBILITIES
AFTER THE BULK SHOWERS AND THUNDERSTORMS ENDS AND BEFORE SUNSET
BUT CONFIDENCE IS LOW ON THE TIMING ANY AMOUNT OF IMPROVEMENT.
AFTER 00Z CEILINGS WILL LOWER TO IFR. FOG WILL ALSO DEVELOP
OVERNIGHT... WITH THE LOWER VISIBILITIES EAST OF THE BLUE RIDGE.
SURFACE RIDGE OF HIGH PRESSURE GRADUALLY BUILDING IN BEHIND THE
FRONT FROM THE NORTHEAST WILL ALLOW FOR A SLOW RETURN TO VFR
CONDITIONS IN MOST AREAS BY FRIDAY NIGHT.
MEDIUM CONFIDENCE IN CEILINGS AND VISIBILITIES DURING THE TAF
PERIOD. HIGH TO MEDIUM CONFIDENCE IN WINDS DURING THE PERIOD.
VFR CONDITIONS WILL PREVAIL...BUT SOME LOCALIZED MVFR
RESTRICTIONS MAY STILL PERSIST INTO THE WEEKEND ACROSS THE
SOUTHWEST MOUNTAINS...MAINLY SOUTH OF KBLF. BY SUNDAY NIGHT AND
MONDAY THE ENTIRE REGION WILL TRANSITION BACK TO VFR CONDITIONS.
&&
.RNK WATCHES/WARNINGS/ADVISORIES...
VA...NONE.
NC...NONE.
WV...NONE.
&&
$$
SYNOPSIS...AMS
NEAR TERM...AMS/KK
SHORT TERM...KM
LONG TERM...WP
AVIATION...AMS/KK
AREA FORECAST DISCUSSION
NWS PORTLAND OR
255 PM PDT THU MAY 29 2014
.SYNOPSIS...A WEAK UPPER LEVEL TROUGH OF LOW PRES OVER THE PACIFIC
NW WILL LINGER INTO THE WEEKEND...BEFORE MOVING E OVER THE WEEKEND.
SURFACE HIGH PRES OVER THE NE PACIFIC WILL STRENGTHEN THIS WEEKEND
BRINGING AND ONSHORE FLOW THAT WILL LAST THROUGH EARLY NEXT WEEK.
&&
.SHORT TERM...THE UPPER TROUGH SEEN IN WATER VAPOR PICTURES TODAY
OVER THE PACIFIC NW IS FORECAST BY MODELS TO LINGER INTO SAT...
BEFORE PUSHING OFF TO THE E. DESPITE THE TROUGH...12Z SOUNDINGS AT
UIL SLE AND MFR ALL SHOWED A SUBSIDENCE INVERSION BETWEEN 850 MB AND
700 MB THIS MORNING. MODEL SOUNDINGS INDICATE THE SUBSIDENCE TO
CONTINUE TO STRENGTHEN A BIT AND LOWER THROUGH TONIGHT. AS LOW LEVEL
FLOW TURNS MORE NORTHERLY TONIGHT EXPECT CLOUDS TO BREAK UP FURTHER
THIS EVENING...WITH CLOUDS BECOMING A LITTLE MORE CONCENTRATED
CLOSER TO THE COAST.
NOT A LOT OF MOISTURE EXPECTED TO WORK WITH FRI AND SAT OUTSIDE OF
RESIDUAL LOW LEVEL MOISTURE. MODEL SOUNDINGS DO INDICATE MARGINAL
INSTABILITY OVER THE CASCADES FRI AFTERNOON AND AGAIN SAT AFTERNOON.
POTENTIAL INSTABILITY IS DEEP ENOUGH TO MAINTAIN A SLIGHT CHANCE FOR
THUNDERSTORMS OVER THE HIGH CASCADES AND IN TO THE HOOD RIVER
VALLEY. GFS AND ECWMF BOTH SHOW A SHORT WAVE ROTATING THROUGH SW WA
AND NW OREGON FRI NIGHT...ALTHOUGH LITTLE MOISTURE ACCOMPANIES IT.
WILL EXTEND A SLIGHT CHANCE FOR SHOWERS OVER THE CASCADES THROUGH
THE LATTER PART OF FRI NIGHT. TEMPS WILL WARM BACK A BIT ABOVE
NORMALS FRI IN RESPONSE TO SUBSIDENCE AND WARMING 850 MB TEMPS.
THE MAIN TROUGH SHIFTS E SAT NIGHT AND SUN...ALTHOUGH REGION REMAINS
UNDER A BROAD CYCLONIC FLOW ON THE BACKSIDE OF THE LOW.
STRENGTHENING HIGH PRES OFFSHORE WILL KEEP A MARINE AIR MASS OVER
THE REGION THROUGH SUN WITH ONSHORE FLOW. SOME HINTS IN MODELS AT
ANOTHER WEAK SHORTWAVE ARRIVING SUN MORNING WHICH COUPLED WITH
MARINE MOISTURE WILL KEEP A SLIGHT CHANCE FOR MORNING SHOWERS NEAR
THE COAST SUNDAY.
.LONG TERM...SUNDAY NIGHT THROUGH THURSDAY...A RIDGE OF HIGH
PRESSURE WILL REMAIN OFFSHORE NEXT WEEK WITH NORTHERLY FLOW OVER THE
REGION. THIS PATTERN WILL BRING SEVERAL DAYS OF DRY WEATHER TO THE
REGION NEXT WEEK. TEMPERATURES WILL RUN NEAR NORMAL ALONG THE COAST
AND 2 TO 4 DEGREES ABOVE NORMAL INLAND. TW
&&
.AVIATION...VFR CIGS 050-070 WILL CONTINUE THRU 02Z ALONG THE
COAST AND N AND CENTRAL WILLAMETTE VALLEY WITH TOPS AROUND 080.
SCATTERED CLOUDS OVER THE SOUTHERN VALLEY AND THE CASCADES AND
FOOTHILLS IN LANE COUNTY. THESE CLOUDS WILL PROBABLY BECOME
SCATTERED OVER MUCH OF THE INLAND AREAS AFTER SUNSET. STRATUS
EXPECTED RE FORM OVERNIGHT OVER THE N INTERIOR AND SOUTHWEST
WASHINGTON AROUND 020 FOR MVFR CIGS AFTER 12Z. THIS STRATUS WILL
LIKELY DISSIPATE LATER BY FRIDAY AFTERNOON. HIGH AND MID CLOUDS
EXPECTED TO MOVE DOWN FROM THE NORTH ASSOCIATED WITH AN UPPER
TROUGH THAT WILL MOVE SOUTH ON FRIDAY.
KPDX AND APPROACHES...VFR WITH SCT-BKN 060 THRU 03Z FRIDAY...
BECOMING SCATTERED CLOUDS 060 AFT 21Z. THERE IS A 50% CHANCE OF MVFR
CIG AT THE TERMINAL 12Z-18Z. SCHNEIDER
&&
.MARINE...THERMAL TROUGH BEGINNING TO FORM ALONG THE S OREGON
COAST THIS AFTERNOON AND WILL STRENGTHEN A LITTLE THIS EVENING.
THE THERMAL TROUGH SHIFTS INLAND BY FRIDAY AFTERNOON IN RESPONSE
TO AN UPPER LEVEL LOW MOVING SOUTH FROM WASHINGTON AND BRITISH
COLUMBIA. THE PRESSURE GRADIENT WILL REMAIN STRONG DURING THE
AFTERNOONS ALTHOUGH THE DIRECTION WILL FAVOR MORE OF A
WESTNORTHWEST WIND. SINCE WINDS WERE LIGHT TODAY THERE HAS NOT
BEEN TOO MUCH OF A WIND WAVE BUT THEY WILL BE INCREASING TONIGHT
AND TOMORROW. A NORTHWEST SWELL IS EXPECTED TO ARRIVE TONIGHT AND
TOMORROW WHICH WILL INCREASE THE WAVE PERIOD BUT THERE IS NOT
MUCH ENERGY IN THIS SWELL SO SIG WAVE HEIGHTS WILL REMAIN BELOW 7
FT. FOR THE REMAINDER OF THE WEEKEND AND EARLY NEXT WEEK THERE
WILL BE A HIGH PRESSURE OFFSHORE AND LOW PRESSURE INLAND AND
EXPECT SMALL CRAFT WINDS DURING THE AFTERNOON AND EVENING HOURS
MOST DAYS.
SCHNEIDER
&&
.PQR WATCHES/WARNINGS/ADVISORIES...
OR...NONE.
WA...NONE.
PZ...SMALL CRAFT ADVISORY FOR WINDS UNTIL 11 PM PDT FRIDAY FOR
COASTAL WATERS FROM CASCADE HEAD OR TO FLORENCE OR OUT 60 NM.
&&
$$
MORE WEATHER INFORMATION ONLINE AT...
HTTP://WEATHER.GOV/PORTLAND
INTERACT WITH US VIA SOCIAL MEDIA
WWW.FACEBOOK.COM/US.NATIONALWEATHERSERVICE.PORTLAND.GOV
WWW.TWITTER.COM/NWSPORTLAND
THIS DISCUSSION IS FOR NORTHWEST OREGON AND SOUTHWEST WASHINGTON FROM
THE CASCADE CREST TO 60 NAUTICAL MILES OFFSHORE. THE AREA IS COMMONLY
REFERRED TO AS THE FORECAST AREA.
[top]
Area Forecast Discussion
National Weather Service Spokane WA
246 PM PDT THU MAY 29 2014
.SYNOPSIS...
Showers and isolated thunderstorms will be confined mainly to the
northern mountains this evening as a low pressure system pulls
away from the region. Much warmer weather develops Friday and
continues into the weekend. Many areas will be in the upper 70s
to lower 80s Friday through Wednesday. Most areas will be dry
through the middle of next week...shower or thunderstorm
development is possible in the mountains each afternoon and
evening.
&&
.DISCUSSION...
Tonight: Although temperatures are warming aloft with the upper
level low pressure system well off to the northeast now, we are
still holding onto to some weak surface based instability across
the Northeast Mtns. A weak impulse moving through the northwest
flow out of BC is triggering a batch of showers near Republic. The
HRRR model takes these showers and slides them southeast with time
this evening. This will impact the communities of Colville,
Metaline Falls and eventually into Sandpoint and Bonners Ferry if
they continue to hold together that long. These showers seem to
be producing fairly weak updrafts due to only a marginally
unstable atmosphere, so not convinced we will see any lightning
from these showers through the rest of the afternoon into the
evening; however, guidance off of the HRRR and SPC SREF page
indicates a slight chance that we could still see a thunderstorm
develop up till about 8:00 PM this evening or so. Showers will
quickly dissipate over the evening as we lose our daytime heating.
Skies will clear out overnight with dew points sitting in the low
to mid 30s. Winds will also be light and strong radiational
cooling is anticipated to take place overnight. Expect lows
tonight to drop into the low to mid 30s across the northern
valleys and colder pockets may drop down to freezing; this will
include locations such as Republic, Springdale and Republic. With
the idea that showers will continue into the evening across the
northern mountains, I added patchy fog to the forecast for late
tonight into early Friday morning.
Friday: We will see a significant rise to temperatures tomorrow of
around 8-10 degrees compared to this afternoon. This will begin a
warming trend into the weekend. Another upper level disturbance,
currently located in northwestern BC, will begin to drop down into
the northern WA Cascades by the afternoon. This will result in
some developing showers north of the Canadian border in BC and
along the Cascade Mtns. These showers may also produce a few
thunderstorms; all other areas will likely remain dry. /SVH
Fri Nt through Sunday: The entire weekend will be dominated by a
slow-moving upper trough...first moving into Ern Wa and N Id Fri
Nt, then not exiting into Wrn Montana until late Sunday. This low
will weaken slowly in general, and is not showing the magnitude
of stretching/strong weakening as model guidance hinted at
yesterday. The good new, at least confidence- wise, is that there
is much more agreement between guidance versus the previous runs.
Even so, there will still be a number of embedded vort maxes
within this upper low, each having the potential to enhance
localized regions of heavier convective pcpn. But given the lack
of notable instability, it`s likely that the pcpn will be dominated
by diurnal processes...ie, the vast majority of the pcpn will be
confined to the afternoon/early evening and driven mostly by
insolation (peak heating) over the elevated heat and moisture
sources of the mountain zones. We`ll be watching closely how these
embedded vort maxes evolve according to the models, then try to
fine tune the fcst to locate the best potential for showers and
thunderstorms. bz
Sunday evening through Thursday...Longwave trof continues to
influence the majority of this time interval. The synoptic
features nested in this longwave trof include a parts of a
shortwave trof and embedded low along with minor disturbances
rotating around its periphery lifting out slowly and clumsily
Sunday evening into Monday evening. This may result in relatively
low pops depicting the low potential for showers and
thunderstorms. Tuesday morning into Tuesday afternoon there is
another hint at a shortwave trof dropping down in a northwest to
southeast trajectory that may be more of a breezy wind and wind
gust maker in addition to having some potential for light
precipitationso more wording for showers and thunderstorms
remain in various shape or form over North Idaho and over and near
the mountainous terrain of Northeast Washington. Wednesday and
Thursday the flow over Eastern Washington and North Idaho still
remains somewhat trof like in appearance but the ECMWF and GFS
differ in timing and passage of northwest to southeast traversing
synoptic/mesoscale features through the trof. So all in all there
really isn`t a period void of pops or a mention of convection in
some shape or form in the forecast area. Since the trof isn`t
substantially deep daytime heating and not too much cloud cover to
inhibit it should result in forecast temperatures on slightly on
the warm side of what would be considered normal for this time of
year. /Pelatti
&&
.AVIATION...
18Z TAFS: An upper level low pressure system will begin to exit
the region today. Some weak surface based instability will result
in a redevelopment of showers this afternoon over the mountains.
Isolated thunderstorms will be possible across the northern
mountains of eastern WA and in the ID Panhandle, but will not
impact the taf sites. All taf locations will see some flat cumulus
in the afternoon with VFR conditions expected through 18Z Friday.
/SVH
&&
.PRELIMINARY POINT TEMPS/POPS...
Spokane 45 74 50 78 51 78 / 10 0 10 10 20 10
Coeur d`Alene 39 75 46 78 51 78 / 10 0 10 20 20 20
Pullman 36 74 45 75 49 76 / 0 0 20 20 20 20
Lewiston 45 81 52 80 54 82 / 0 0 10 20 20 20
Colville 41 75 44 79 49 80 / 20 10 10 10 10 10
Sandpoint 37 74 44 76 46 72 / 10 0 0 10 10 20
Kellogg 41 74 45 76 48 74 / 0 0 10 20 20 30
Moses Lake 44 80 50 83 51 84 / 0 0 0 0 0 0
Wenatchee 50 80 56 82 56 84 / 0 0 0 0 0 0
Omak 41 78 48 81 49 83 / 10 10 10 0 10 10
&&
.OTX WATCHES/WARNINGS/ADVISORIES...
ID...None.
WA...None.
&&
$$