Forecast Discussions mentioning any of
"HRRR" "RAP" "RR" "RUC13" "RUC" received at GSD on 06/24/15
AREA FORECAST DISCUSSION
NWS PHOENIX AZ
307 PM MST MON JUN 22 2015
.SYNOPSIS...
ABOVE NORMAL TEMPERATURES WILL PERSIST ACROSS THE REGION THROUGH MUCH
OF THE UPCOMING WEEK...BUT WILL RETREAT FROM THE RECORD-TYING VALUES
SEEN LAST WEEK. MEANWHILE...MOISTURE WILL BEGIN TO MOVE INTO THE AREA
FROM MEXICO...WITH INCREASING CHANCES OF MOUNTAIN SHOWERS AND
THUNDERSTORMS FROM WEDNESDAY ONWARD. THERE IS ALSO INCREASING CHANCES
FOR THUNDERSTORM IMPACTS SUCH AS GUSTY WINDS AND BLOWING DUST.
&&
.DISCUSSION...
LATEST STREAMLINE ANALYSIS SHOWS THE MONSOON HIGH ACROSS
NM...SPRAWLED OUT EAST TO WEST WITH A WARM SOUTHERLY FLOW ACROSS THE
DESERT SOUTHWEST. TWC 12Z SOUNDING MEASURED A PWAT OF 1.12
INCHES...WHICH IS ABOVE NORMAL FOR THIS TIME OF YEAR...THOUGH SURFACE
DEWPOINTS ACROSS THE LOWER DESERTS ARE CONSIDERABLY LOWER THAN THEY
WERE THIS TIME YESTERDAY.
LATEST CONVECTIVE ALLOWING MODELS INCLUDING THE HRRR CONTINUE TO
SUGGEST THAT ISOLATED SHOWERS AND THUNDERSTORMS WILL DEVELOP THIS
AFTERNOON ACROSS FAR SE AZ...BUT WITH NO IMPACT ACROSS SOUTH-
CENTRAL AZ. LATEST SATELLITE IMAGERY SHOWS THAT CONVECTION IS HAVING
A DIFFICULT TIME INITIATING IN THESE AREAS BUT LOOKS MORE FAVORABLE
ACROSS THE WHITE MOUNTAINS. FOR TONIGHT...EXPECT MOSTLY CLEAR SKIES
WITH A CONTINUATION OF THE ABOVE NORMAL TEMPERATURES.
MODELS INDICATE THAT THE SOUTHERLY FLOW WILL PERSIST TUESDAY. A
SLIGHT BUMP IN THICKNESSES WILL YIELD AN INCREASE IN TEMPERATURES AND
AN EXCESSIVE HEAT WARNING REMAINS IN EFFECT FOR MUCH OF THE AREA.
INCREASING MOISTURE WILL TAKE A BITE OUT OF THE TEMPERATURES
WEDNESDAY...PARTICULARLY ACROSS EASTERN AZ...THOUGH THE LATEST
BLENDS SUGGEST THAT AN EXCESSIVE HEAT WARNING IS AGAIN WARRANTED FOR
SOUTH AND WEST-CENTRAL AZ.
&&
.PREVIOUS DISCUSSION...
THE FORECAST TURNS DECIDEDLY MORE MONSOON-LIKE ON WEDNESDAY AS THE
RIDGE AXIS THAT BROUGHT US THE RECENT STRETCH OF HEAT SHIFTS TO THE
EAST AND EAST/SOUTHEAST FLOW SETS UP ACROSS MUCH OF ARIZONA. GFS/EURO
BL MIXING RATIOS START TO CLIMB TO AROUND 6 G/KG AROUND THE PHOENIX
AREA...WITH VALUES CLOSER TO 8 G/KG ACROSS FAR EASTERN ARIZONA. BOTH
MODELS INDICATE A FEW HUNDRED J/KG MLCAPE AHEAD OF A WEAK INVERTED
TROUGH AND NOT SURPRISINGLY...SEVERAL HI-RES MODELS SUGGEST
CONVECTION DEVELOPING ALONG THE HIGHER TERRAIN EAST OF PHOENIX AND
DESCENDING INTO THE DESERTS WEDNESDAY AFTERNOON. MLCAPES QUICKLY DROP
OFF TO ZERO AROUND THE PHOENIX METRO SO ANY PRECIP THAT FALLS SHOULD
BE CONFINED TO THE MOUNTAINS. HOWEVER THERE`S CERTAINLY A NON-ZERO
CHANCE OF COLLIDING OUTFLOWS TRIGGERING NEW STORMS AND I MADE SOME
UPWARD ADJUSTMENTS TO POPS WEDNESDAY EVENING. WILL NEED ASSESS THE
POSSIBILITY OF BLDU WEDNESDAY AFTERNOON/EVENING. IF THE FORECAST
PLAYS OUT AS ADVERTISED...DUST MAY BE LOCALIZED IN NATURE GIVEN THE
DIRECTION FROM WHICH THE OUTFLOWS ARE ORIGINATING /MOUNTAINS NE OF
PHOENIX/. IF STORMS END UP DEVELOPING ACROSS PORTIONS OF SOUTHEAST
ARIZONA...MORE WIDESPREAD DUST AND DUST-RELATED IMPACTS ARE POSSIBLE.
EAST/SOUTHEAST FLOW FORECAST TO CONTINUE EACH DAY THROUGH THE END OF
THE FORECAST PERIOD. BL MOISTURE REMAINS MARGINAL ACROSS THE DESERTS
THROUGH THE END OF THE WEEK BUT SHOULD BE SUFFICIENT IN THE MOUNTAINS
FOR MEASURABLE PRECIP. POPS WERE ALSO RAISED IN THE MOUNTAINS THROUGH
SATURDAY. I WOULD GO HIGHER BUT AT LEAST AT THIS POINT THERE AREN`T
ANY OBVIOUS TRIGGERS/TROUGHS/PV ANOMALIES IN THE FLOW TO WARRANT
ANYTHING HIGHER THAN 20-30 POPS. BETTER CHANCES APPEAR TO BE NEXT
SUNDAY WHEN MORE SUBSTANTIAL BL MOISTURE /MIXING RATIOS AROUND 7-9
G/KG/ OVERSPREADS THE AREA IMMEDIATELY AHEAD OF A WEAK INVERTED
TROUGH. SUNDAY LOOKS TO BE THE MOST PROMISING DAY FOR SHOWERS AND
THUNDERSTORMS ACROSS THE DESERTS ALTHOUGH CONFIDENCE IN EARLY-SEASON
EVENTS IS ALWAYS LOW.
&&
.AVIATION...SOUTH-CENTRAL ARIZONA INCLUDING KPHX...KIWA...AND
KSDL...SOUTHEAST CALIFORNIA AND SOUTHWEST ARIZONA INCLUDING KIPL AND
KBLH...
SOUTHWEST AND WEST DIRECTIONS WILL BE FAVORED THROUGH TUESDAY OVER
SOUTH-CENTRAL ARIZONA...INCLUDING PHOENIX METRO...AND SOUTHERLY
ELSEWHERE. ANTICIPATE LIGHT AND VARIABLE CONDITIONS FROM ABOUT 09Z-
16Z. SKIES WILL BE CLEAR THE REST OF THE AFTERNOON AND NIGHT
OVER THE TAF SITES WITH CUMULUS BUILDUPS LIMITED TO THE WHITE
MOUNTAINS AREA. STORM ACTIVITY OVER SONORA MAY LEAD TO SOME REMNANT
DEBRIS CLOUDINESS AOA FL180 AFTER 12Z...MORE LIKELY FOR SOUTHWEST
ARIZONA AND SOUTHEAST CALIFORNIA. ANTICIPATE MORE CUMULUS BUILDUPS
AND ISOLATED STORMS OVER WHITE MOUNTAINS AND SOUTHEAST ARIZONA
TUESDAY WITH EVEN MORE COVERAGE WEDNESDAY.
AVIATION DISCUSSION NOT UPDATED FOR AMENDED TAFS.
&&
.FIRE WEATHER...THURSDAY THROUGH MONDAY...
STORM CHANCES EXPAND TO THE LOWER DESERTS OF SOUTH-CENTRAL ARIZONA
THURSDAY AND EXPANDS TO THE LOWER COLORADO RIVER VALLEY BY
SUNDAY...ALONG WITH JOSHUA TREE NATIONAL PARK. THUS STRONG
THUNDERSTORM RELATED WINDS AND LIGHTNING BECOME MORE LIKELY WITH
TIME. TEMPERATURES WILL ALSO BE CLOSER TO NORMAL. MINIMUM
HUMIDITY VALUES WILL GENERALLY BE 10-20 PERCENT WITH GOOD OVERNIGHT
RECOVERY.
&&
.SPOTTER INFORMATION STATEMENT...
SPOTTERS ARE ENCOURAGED TO REPORT ANY SIGNIFICANT WEATHER CONDITIONS
ACCORDING TO STANDARD OPERATING PROCEDURES.
&&
.PSR WATCHES/WARNINGS/ADVISORIES...
AZ...EXCESSIVE HEAT WARNING FROM 10 AM TUESDAY TO 8 PM MST WEDNESDAY
FOR AZZ021>023-027-028.
EXCESSIVE HEAT WARNING FROM 10 AM TO 8 PM MST TUESDAY FOR AZZ020-
024>026.
CA...EXCESSIVE HEAT WARNING FROM 10 AM TO 8 PM PDT TUESDAY FOR
CAZ031>033.
&&
$$
VISIT US ON FACEBOOK...TWITTER...AND AT WEATHER.GOV/PHOENIX
DISCUSSION...HIRSCH
PREVIOUS DISCUSSION...LEINS
AVIATION...AJ
FIRE WEATHER...AJ
AREA FORECAST DISCUSSION
NWS PHOENIX AZ
920 AM MST MON JUN 22 2015
.SYNOPSIS...
ABOVE NORMAL TEMPERATURES WILL PERSIST ACROSS THE REGION THROUGH MUCH
OF THE UPCOMING WEEK...BUT WILL RETREAT FROM THE RECORD-TYING VALUES
SEEN LAST WEEK. MEANWHILE...MOISTURE WILL BEGIN TO MOVE INTO THE AREA
FROM MEXICO...WITH INCREASING CHANCES OF MOUNTAIN SHOWERS AND
THUNDERSTORMS FROM WEDNESDAY ONWARD.
&&
.DISCUSSION...
LATEST STREAMLINE ANALYSIS SHOWS THE MONSOON HIGH ACROSS
NM...SPRAWLED OUT EAST TO WEST WITH A WARM SOUTHERLY FLOW ACROSS THE
DESERT SOUTHWEST. TWC 12Z SOUNDING MEASURED A PWAT OF 1.12
INCHES...WHICH IS ABOVE NORMAL FOR THIS TIME OF YEAR...THOUGH SURFACE
DEWPOINTS ACROSS THE LOWER DESERTS ARE CONSIDERABLY LOWER THAN THEY
WERE THIS TIME YESTERDAY.
LATEST CONVECTIVE ALLOWING MODELS INCLUDING THE HRRR CONTINUE TO
SUGGEST THAT ISOLATED SHOWERS AND THUNDERSTORMS WILL DEVELOP ACROSS
FAR SE AZ TODAY...BUT WITH NO IMPACT ACROSS SOUTH-CENTRAL AZ.
ALTHOUGH EXCESSIVE HEAT IS NOT EXPECTED TODAY...TEMPERATURES WILL
CONTINUE A FEW DEGREES ABOVE AVERAGE. SOME MINOR ADJUSTMENTS WERE
MADE TO THE SHORT-TERM TEMPERATURES AND DEWPOINTS. OTHERWISE...FORECAST
REMAINS ON TRACK.
&&
.PREVIOUS DISCUSSION...
QUITE A BIT OF MOISTURE MADE ITS WAY INTO THE DESERTS ON SUNDAY AND
DEWPOINTS NEVER MIXED OUT SUBSTANTIALLY DURING THE AFTERNOON HOURS.
PWATS ACROSS THE AREA WILL BE VERY SIMILAR TO THOSE SEEN ON
SUNDAY...FORECAST SOUNDINGS ALSO INDICATE DEWPOINTS WILL ONLY MIX
INTO THE LOW/MID 40S LATER TODAY. THESE FACTORS...IN ADDITION TO THE
POSSIBILITY OF SOME HIGH CLOUDS MOVING INTO THE AREA COURTESY OF THE
DECAYING COMPLEX OF STORMS SHOULD LIMIT HOW HIGH TEMPERATURES WILL
RISE TODAY. IN MANY LOCATIONS...TEMPS SHOULD ONLY BE ABOUT 2-3
DEGREES ABOVE CLIMATOLOGICAL NORMALS FOR LATE JUNE. HOWEVER LOOKING
AHEAD TO TUESDAY...925-850MB TEMPS ARE FORECAST TO RISE A DEGREE OR
TWO WITH DESERT HIGHS ONCE AGAIN RETURNING TO THE 110-114 RANGE.
GOING TO MAKE SOME ADJUSTMENTS TO THE EXCESSIVE HEAT WARNING AND WILL
DROP IT FOR TODAY...BUT LEAVE IT IN EFFECT ON TUESDAY. WILL EMPHASIZE
THAT TODAY`S HIGHS WILL BE A BRIEF REPRIEVE FROM RECORD-TYING TEMPS
OF LAST WEEK...BUT THAT DANGEROUSLY HOT TEMPS ARE POSSIBLE ONCE AGAIN
ON TUESDAY.
THE FORECAST TURNS DECIDEDLY MORE MONSOON-LIKE ON WEDNESDAY AS THE
RIDGE AXIS THAT BROUGHT US THE RECENT STRETCH OF HEAT SHIFTS TO THE
EAST AND EAST/SOUTHEAST FLOW SETS UP ACROSS MUCH OF ARIZONA.
GFS/EURO BL MIXING RATIOS START TO CLIMB TO AROUND 6 G/KG AROUND THE
PHOENIX AREA...WITH VALUES CLOSER TO 8 G/KG ACROSS FAR EASTERN
ARIZONA. BOTH MODELS INDICATE A FEW HUNDRED J/KG MLCAPE AHEAD OF A
WEAK INVERTED TROUGH AND NOT SURPRISINGLY...SEVERAL HI-RES MODELS
SUGGEST CONVECTION DEVELOPING ALONG THE HIGHER TERRAIN EAST OF
PHOENIX AND DESCENDING INTO THE DESERTS WEDNESDAY AFTERNOON. MLCAPES
QUICKLY DROP OFF TO ZERO AROUND THE PHOENIX METRO SO ANY PRECIP THAT
FALLS SHOULD BE CONFINED TO THE MOUNTAINS. HOWEVER THERE`S CERTAINLY
A NON-ZERO CHANCE OF COLLIDING OUTFLOWS TRIGGERING NEW STORMS AND I
MADE SOME UPWARD ADJUSTMENTS TO POPS WEDNESDAY EVENING. WILL NEED
ASSESS THE POSSIBILITY OF BLDU WEDNESDAY AFTERNOON/EVENING. IF THE
FORECAST PLAYS OUT AS ADVERTISED...DUST MAY BE LOCALIZED IN NATURE
GIVEN THE DIRECTION FROM WHICH THE OUTFLOWS ARE ORIGINATING
/MOUNTAINS NE OF PHOENIX/. IF STORMS END UP DEVELOPING ACROSS
PORTIONS OF SOUTHEAST ARIZONA...MORE WIDESPREAD DUST AND DUST-RELATED
IMPACTS ARE POSSIBLE.
EAST/SOUTHEAST FLOW FORECAST TO CONTINUE EACH DAY THROUGH THE END OF
THE FORECAST PERIOD. BL MOISTURE REMAINS MARGINAL ACROSS THE DESERTS
THROUGH THE END OF THE WEEK BUT SHOULD BE SUFFICIENT IN THE MOUNTAINS
FOR MEASURABLE PRECIP. POPS WERE ALSO RAISED IN THE MOUNTAINS THROUGH
SATURDAY. I WOULD GO HIGHER BUT AT LEAST AT THIS POINT THERE AREN`T
ANY OBVIOUS TRIGGERS/TROUGHS/PV ANOMALIES IN THE FLOW TO WARRANT
ANYTHING HIGHER THAN 20-30 POPS. BETTER CHANCES APPEAR TO BE NEXT
SUNDAY WHEN MORE SUBSTANTIAL BL MOISTURE /MIXING RATIOS AROUND 7-9
G/KG/ OVERSPREADS THE AREA IMMEDIATELY AHEAD OF A WEAK INVERTED
TROUGH. SUNDAY LOOKS TO BE THE MOST PROMISING DAY FOR SHOWERS AND
THUNDERSTORMS ACROSS THE DESERTS ALTHOUGH CONFIDENCE IN EARLY-SEASON
EVENTS IS ALWAYS LOW.
&&
.AVIATION...
SOUTH-CENTRAL ARIZONA INCLUDING KPHX...KIWA...AND KSDL...
SOUTHEAST CALIFORNIA AND SOUTHWEST ARIZONA INCLUDING KIPL AND KBLH...
HOT AND DRY CONDITIONS TO CONTINUE TODAY WITH AM SKIES SEEING SOME
DEBRIS CLOUDINESS MOVING IN FROM THE SOUTH AND GRADUALLY DISSIPATING
INTO THE DAY. SOUTH-SOUTHEASTERLY WINDS WILL CONTINUE FOR KIPL AND
KBLH. PHOENIX AREA TERMINALS WILL MAINTAIN LIGHT WESTERLY HEADINGS
THIS AM BEFORE SPEEDS GRADUALLY INCREASE INTO THE AFTERNOON HOURS.
AVIATION DISCUSSION NOT UPDATED FOR AMENDED TAFS.
&&
.FIRE WEATHER...
WEDNESDAY THROUGH SUNDAY...
DEEP MOISTURE OVER MEXICO AND THE SOUTHERN PLAINS IS EXPECTED TO
MOVE INTO MAINLY SOUTHERN AND EASTERN ARIZONA AS THE WEEK PROGRESSES
WHICH WILL LEAD TO INCREASING HUMIDITIES...CLOUDS...AND THE CHANCES
FOR THUNDERSTORMS OVER THE ARIZONA HIGHER TERRAIN. BEFORE THE DEEP
MOISTURE ARRIVES...SHALLOW INCURSIONS OF HUMID AIR ARE ANTICIPATED
FROM TIME TO TIME. THUNDERSTORM ACTIVITY OVER SONORA MEXICO COULD
LEAD TO MORE RAPID ONSET OF HIGHER HUMIDITIES AND STORM CHANCES.
CONVERSELY...IF THE DEEP MOISTURE REMAINS AT BAY AND THE SHALLOW
INCURSIONS OF MOISTURE DO NOT MATERIALIZE...THEN VERY HIGH
TEMPERATURES...HIGH HAINES VALUES...AND LOW HUMIDITIES CAN BE
EXPECTED.
&&
.SPOTTER INFORMATION STATEMENT...
SPOTTERS ARE ENCOURAGED TO REPORT ANY SIGNIFICANT WEATHER CONDITIONS
ACCORDING TO STANDARD OPERATING PROCEDURES.
&&
.PSR WATCHES/WARNINGS/ADVISORIES...
AZ...EXCESSIVE HEAT WARNING FROM 10 AM TO 8 PM MST TUESDAY FOR
AZZ020>028.
CA...EXCESSIVE HEAT WARNING FROM 10 AM TO 8 PM PDT TUESDAY FOR
CAZ031>033.
&&
$$
VISIT US ON FACEBOOK...TWITTER...AND AT WEATHER.GOV/PHOENIX
DISCUSSION...HIRSCH
PREVIOUS DISCUSSION...LEINS
AVIATION...NOLTE
FIRE WEATHER...AJ
AREA FORECAST DISCUSSION
NWS PUEBLO CO
1232 PM MDT MON JUN 22 2015
.UPDATE...
ISSUED AT 1229 PM MDT MON JUN 22 2015
UPDATED TEMPS AND WINDS FOR THE AFTERNOON. TEMPS HAVE BEEN FALLING
ON THE PLAINS BEHIND THE FRONT...AND WHILE SOME AREAS MAY BOUNCE
BACK A FEW DEGREES...SUSPECT MANY LOCATIONS ARE NEAR OR HAVE
ALREADY HIT THEIR HIGHS FOR THE DAY.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 506 AM MDT MON JUN 22 2015
SHORTWAVE MOVING ALONG THE NORTHERN TIER COMBINED WITH OUTFLOW FROM
MCS ACROSS THE DAKOTAS WILL SEND A FRONT THROUGH SOUTHEAST COLORADO
THIS AFTERNOON. MSAS 3HR PRESSURE CHANGE CHARTS SHOW AROUND 3-5 MB
PRESSURE RISES ACROSS EASTERN WY. HRRR AND NAM12 BRING THE FRONT
INTO NORTHEAST CO AROUND 12Z...WHICH WILL CONTINUE SOUTHWARD INTO
SOUTHEAST COLORADO DURING THE LATE MORNING AND AFTERNOON HOURS.
GUSTY NORTH WINDS WILL SHIFT AROUND FROM THE EAST. INITIALLY WINDS
WILL MIX OUT SHALLOW MOISTURE NEAR THE SURFACE...BUT BY AFTERNOON
SHOULD SEE DEW POINTS INCREASE AGAIN FROM WEST TO EAST AS COOLER AND
MORE STABLE AIRMASS PUSHES IN. ANY POPS TODAY SHOULD STAY CONFINED
TO LOCATIONS ALONG THE FRONT WHICH WILL BE IN THE VICINITY OF THE
RATON MESA REGION...THOUGH STRONG CAP FROM RIDGING ALOFT SHOULD
SUPPRESS ANY CONVECTION UNTIL THE LATE AFTERNOON EARLY EVENING
HOURS. WILL MAINTAIN THE LOW GRADE ISOLATED POPS ACROSS THE
SOUTHERN PORTIONS OF THE SE PLAINS...AS WELL AS THE WETS AND PERHAPS
THE PIKES PEAK REGION. WITH QUITE A BIT OF CIN BEHIND THE
FRONT...THINK ANY THUNDERSTORMS SHOULD DIMINISH QUICKLY AS THEY PUSH
OFF THE MOUNTAINS. EXCEPTION TO THIS MAY BE ALONG THE RATON MESA
REGION WHERE CONVERGENCE MAY BE SUFFICIENT ALONG THE FRONT TO
FIRE/MAINTAIN ONE OR TWO STRONGER STORMS. HOWEVER...DEEP LAYER
SHEARS APPEAR FAIRLY WEAK IN THIS REGION...SO SEVERE THREAT LOOKS
LOW TODAY. TEMPERATURES TODAY WILL BE A CHALLENGE. WENT SLIGHTLY
COOLER FOR THE PLAINS THAN WHAT OCCURRED YESTERDAY...BUT TIMING OF
FRONT WILL MEAN EVERYTHING. TRENDED TOWARDS THE WARMER SIDE OF
CONSENSUS GRIDS...THOUGH NOT AS WARM AS OVERLY WARM MET/MAV GUIDANCE
IS GOING. MEANWHILE...FORECAST PERSISTENCE LOOKS BEST FOR THE
MOUNTAINS AND VALLEYS AS H7 TEMPERATURES ARE PRETTY SIMILAR TO
YESTERDAY.
MODELS DIFFER IN COVERAGE OF THUNDERSTORMS ACROSS THE PLAINS.
ALWAYS LEERY OF A LOW LEVEL JET IN VCNTY OF THE FRONT ACROSS THE
AREA...AS IT COULD GENERATE THUNDERSTORMS NORTH OF THE FRONT WITH
UPGLIDE. HOWEVER...CAP IS QUITE STOUT IN MODEL SOUNDINGS...AND NOT
SURE IF UPGLIDE WILL BE STRONG ENOUGH TO BREACH IT. NAM12 IS PRETTY
DRY...GFS KEEPS ANY SHOWER/THUNDERSTORM POTENTIAL FARTHER TO THE
NORTHEAST...THOUGH DOES HAVE SOME LIGHT QPF OVER THE UPSLOPE REGIONS
OF THE SE MTS. ARW LOOKS FAIRLY DRY...AND NMM PRINTS OUT WHAT LOOKS
LIKE SOME STRATIFORM SHOWERS/LIGHT QPF ACROSS NORTHEAST SECTIONS OF
THE AREA LATE TONIGHT. FOR NOW...KEPT POPS IN THE EVENING ALONG THE
SOUTHERN BORDER OF THE SOUTHEAST PLAINS...WITH SILENT POPS THROUGH
THE NIGHT FOR THE REMAINDER OF THE PLAINS. DID INCREASE SKY COVER
TO ACCOUNT FOR POTENTIAL FOR STRATUS TO DEVELOP ALONG THE SE
MTS/PORTIONS OF THE PLAINS OVERNIGHT. LOWS TONIGHT SHOULD BE COOLER
THAN READINGS THIS MORNING. -KT
.LONG TERM...(TUESDAY THROUGH SUNDAY)
ISSUED AT 506 AM MDT MON JUN 22 2015
SOME ADJUSTMENTS NEEDED DURING THE LONGER TERM WITH PRIMARY
METEOROLOGICAL CONCERNS BEING TEMPERATURES AND POPS...WITH HIGHEST
POTENTIAL OF MORE WIDESPREAD PRECIPITATION EXPECTED FROM FRIDAY
INTO FRIDAY NIGHT.
BY 12Z TUESDAY...UPPER RIDGE LOCATED OVER THE OKLAHOMA/TEXAS
PANHANDLES WILL SHIFT INTO ARKANSAS BY 12Z WEDNESDAY AND THEN
BECOME CENTERED OVER THE SOUTHEASTERN UNITED STATES THROUGH LATE
WEEK WHILE NEXT UPPER RIDGE DEVELOPS OVER THE ARIZONA/UTAH BORDER
FROM LATER THURSDAY INTO THE WEEKEND.
RECENT LONGER TERM COMPUTER SIMULATIONS...PV ANALYSIS AND FORECAST
MODEL SOUNDINGS SUGGEST THAT INCREASED ATMOSPHERIC MOISTURE WILL
DEVELOP OVER MANY SECTIONS OF THE FORECAST DISTRICT FROM LATER
THURSDAY INTO AT LEAST THE EARLY WEEKEND IN COMBINATION WITH
A NORTHEASTERLY TO EASTERLY SURFACE FLOW DEVELOPING ACROSS
EASTERN SECTIONS FROM LATER THURSDAY INTO AT LEAST FRIDAY.
ALSO...UPPER DISTURBANCES WILL BE IMPACTING THE FORECAST
DISTRICT AT TIMES...PRIMARILY FROM LATER THIS WEEK INTO THE
WEEKEND.
INCREASED POPS ARE EXPECTED BY LATER THIS WEEK...MAXIMIZING FROM
FRIDAY INTO FRIDAY NIGHT. IN ADDITION...STRONGER STORMS WILL ALSO
BE POSSIBLE...ESPECIALLY FROM LATER THURSDAY INTO THE WEEKEND AT
LOCALIZED CAPES...LIS AND 0 TO 6 KM BULK SHEARS EXCEED 1500
J/KG...-5C AND 30 KNOTS AT TIMES.
WARMEST CONDITIONS DURING THE LONGER TERM ARE ANTICIPATED FROM
TUESDAY INTO THURSDAY WITH COOLER CONDITIONS THEN EXPECTED FROM
FRIDAY INTO THE WEEKEND.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON)
ISSUED AT 1128 AM MDT MON JUN 22 2015
AT KCOS AND KPUB...COLD FRONT HAS COME THROUGH WITH N-NE WINDS
GRADUALLY BECOMING E-SE THIS AFTERNOON. VFR CIGS/VIS ARE EXPECTED
INTO THIS EVENING...WITH UPSLOPE FLOW THEN PRODUCING SOME STRATUS
AT BOTH TERMINALS LATE TONIGHT THROUGH EARLY TUESDAY MORNING.
CIGS WILL LIKELY RANGE FROM MVFR AT KPUB TO IFR AT KCOS. THERE IS
A SMALL CHANCE OF A -SHRA/-TSRA OVER THE PLAINS LATE TONIGHT INTO
EARLY FRI MORNING...THOUGH WON`T MENTION IN EITHER TAF AT THIS
POINT.
AT KALS...VFR THROUGH THE PERIOD...WITH BREEZY SOUTHWEST
WINDS AROUND 15 KTS EXPECTED THIS AFTERNOON.
&&
.PUB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...PETERSEN
AVIATION...PETERSEN
AREA FORECAST DISCUSSION
NWS PUEBLO CO
1137 AM MDT MON JUN 22 2015
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 506 AM MDT MON JUN 22 2015
SHORTWAVE MOVING ALONG THE NORTHERN TIER COMBINED WITH OUTFLOW FROM
MCS ACROSS THE DAKOTAS WILL SEND A FRONT THROUGH SOUTHEAST COLORADO
THIS AFTERNOON. MSAS 3HR PRESSURE CHANGE CHARTS SHOW AROUND 3-5 MB
PRESSURE RISES ACROSS EASTERN WY. HRRR AND NAM12 BRING THE FRONT
INTO NORTHEAST CO AROUND 12Z...WHICH WILL CONTINUE SOUTHWARD INTO
SOUTHEAST COLORADO DURING THE LATE MORNING AND AFTERNOON HOURS.
GUSTY NORTH WINDS WILL SHIFT AROUND FROM THE EAST. INITIALLY WINDS
WILL MIX OUT SHALLOW MOISTURE NEAR THE SURFACE...BUT BY AFTERNOON
SHOULD SEE DEW POINTS INCREASE AGAIN FROM WEST TO EAST AS COOLER AND
MORE STABLE AIRMASS PUSHES IN. ANY POPS TODAY SHOULD STAY CONFINED
TO LOCATIONS ALONG THE FRONT WHICH WILL BE IN THE VICINITY OF THE
RATON MESA REGION...THOUGH STRONG CAP FROM RIDGING ALOFT SHOULD
SUPPRESS ANY CONVECTION UNTIL THE LATE AFTERNOON EARLY EVENING
HOURS. WILL MAINTAIN THE LOW GRADE ISOLATED POPS ACROSS THE
SOUTHERN PORTIONS OF THE SE PLAINS...AS WELL AS THE WETS AND PERHAPS
THE PIKES PEAK REGION. WITH QUITE A BIT OF CIN BEHIND THE
FRONT...THINK ANY THUNDERSTORMS SHOULD DIMINISH QUICKLY AS THEY PUSH
OFF THE MOUNTAINS. EXCEPTION TO THIS MAY BE ALONG THE RATON MESA
REGION WHERE CONVERGENCE MAY BE SUFFICIENT ALONG THE FRONT TO
FIRE/MAINTAIN ONE OR TWO STRONGER STORMS. HOWEVER...DEEP LAYER
SHEARS APPEAR FAIRLY WEAK IN THIS REGION...SO SEVERE THREAT LOOKS
LOW TODAY. TEMPERATURES TODAY WILL BE A CHALLENGE. WENT SLIGHTLY
COOLER FOR THE PLAINS THAN WHAT OCCURRED YESTERDAY...BUT TIMING OF
FRONT WILL MEAN EVERYTHING. TRENDED TOWARDS THE WARMER SIDE OF
CONSENSUS GRIDS...THOUGH NOT AS WARM AS OVERLY WARM MET/MAV GUIDANCE
IS GOING. MEANWHILE...FORECAST PERSISTENCE LOOKS BEST FOR THE
MOUNTAINS AND VALLEYS AS H7 TEMPERATURES ARE PRETTY SIMILAR TO
YESTERDAY.
MODELS DIFFER IN COVERAGE OF THUNDERSTORMS ACROSS THE PLAINS.
ALWAYS LEERY OF A LOW LEVEL JET IN VCNTY OF THE FRONT ACROSS THE
AREA...AS IT COULD GENERATE THUNDERSTORMS NORTH OF THE FRONT WITH
UPGLIDE. HOWEVER...CAP IS QUITE STOUT IN MODEL SOUNDINGS...AND NOT
SURE IF UPGLIDE WILL BE STRONG ENOUGH TO BREACH IT. NAM12 IS PRETTY
DRY...GFS KEEPS ANY SHOWER/THUNDERSTORM POTENTIAL FARTHER TO THE
NORTHEAST...THOUGH DOES HAVE SOME LIGHT QPF OVER THE UPSLOPE REGIONS
OF THE SE MTS. ARW LOOKS FAIRLY DRY...AND NMM PRINTS OUT WHAT LOOKS
LIKE SOME STRATIFORM SHOWERS/LIGHT QPF ACROSS NORTHEAST SECTIONS OF
THE AREA LATE TONIGHT. FOR NOW...KEPT POPS IN THE EVENING ALONG THE
SOUTHERN BORDER OF THE SOUTHEAST PLAINS...WITH SILENT POPS THROUGH
THE NIGHT FOR THE REMAINDER OF THE PLAINS. DID INCREASE SKY COVER
TO ACCOUNT FOR POTENTIAL FOR STRATUS TO DEVELOP ALONG THE SE
MTS/PORTIONS OF THE PLAINS OVERNIGHT. LOWS TONIGHT SHOULD BE COOLER
THAN READINGS THIS MORNING. -KT
.LONG TERM...(TUESDAY THROUGH SUNDAY)
ISSUED AT 506 AM MDT MON JUN 22 2015
SOME ADJUSTMENTS NEEDED DURING THE LONGER TERM WITH PRIMARY
METEOROLOGICAL CONCERNS BEING TEMPERATURES AND POPS...WITH HIGHEST
POTENTIAL OF MORE WIDESPREAD PRECIPITATION EXPECTED FROM FRIDAY
INTO FRIDAY NIGHT.
BY 12Z TUESDAY...UPPER RIDGE LOCATED OVER THE OKLAHOMA/TEXAS
PANHANDLES WILL SHIFT INTO ARKANSAS BY 12Z WEDNESDAY AND THEN
BECOME CENTERED OVER THE SOUTHEASTERN UNITED STATES THROUGH LATE
WEEK WHILE NEXT UPPER RIDGE DEVELOPS OVER THE ARIZONA/UTAH BORDER
FROM LATER THURSDAY INTO THE WEEKEND.
RECENT LONGER TERM COMPUTER SIMULATIONS...PV ANALYSIS AND FORECAST
MODEL SOUNDINGS SUGGEST THAT INCREASED ATMOSPHERIC MOISTURE WILL
DEVELOP OVER MANY SECTIONS OF THE FORECAST DISTRICT FROM LATER
THURSDAY INTO AT LEAST THE EARLY WEEKEND IN COMBINATION WITH
A NORTHEASTERLY TO EASTERLY SURFACE FLOW DEVELOPING ACROSS
EASTERN SECTIONS FROM LATER THURSDAY INTO AT LEAST FRIDAY.
ALSO...UPPER DISTURBANCES WILL BE IMPACTING THE FORECAST
DISTRICT AT TIMES...PRIMARILY FROM LATER THIS WEEK INTO THE
WEEKEND.
INCREASED POPS ARE EXPECTED BY LATER THIS WEEK...MAXIMIZING FROM
FRIDAY INTO FRIDAY NIGHT. IN ADDITION...STRONGER STORMS WILL ALSO
BE POSSIBLE...ESPECIALLY FROM LATER THURSDAY INTO THE WEEKEND AT
LOCALIZED CAPES...LIS AND 0 TO 6 KM BULK SHEARS EXCEED 1500
J/KG...-5C AND 30 KNOTS AT TIMES.
WARMEST CONDITIONS DURING THE LONGER TERM ARE ANTICIPATED FROM
TUESDAY INTO THURSDAY WITH COOLER CONDITIONS THEN EXPECTED FROM
FRIDAY INTO THE WEEKEND.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON)
ISSUED AT 1128 AM MDT MON JUN 22 2015
AT KCOS AND KPUB...COLD FRONT HAS COME THROUGH WITH N-NE WINDS
GRADUALLY BECOMING E-SE THIS AFTERNOON. VFR CIGS/VIS ARE EXPECTED
INTO THIS EVENING...WITH UPSLOPE FLOW THEN PRODUCING SOME STRATUS
AT BOTH TERMINALS LATE TONIGHT THROUGH EARLY TUESDAY MORNING.
CIGS WILL LIKELY RANGE FROM MVFR AT KPUB TO IFR AT KCOS. THERE IS
A SMALL CHANCE OF A -SHRA/-TSRA OVER THE PLAINS LATE TONIGHT INTO
EARLY FRI MORNING...THOUGH WON`T MENTION IN EITHER TAF AT THIS
POINT.
AT KALS...VFR THROUGH THE PERIOD...WITH BREEZY SOUTHWEST
WINDS AROUND 15 KTS EXPECTED THIS AFTERNOON.
&&
.PUB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AVIATION...PETERSEN
AREA FORECAST DISCUSSION
NWS PUEBLO CO
506 AM MDT MON JUN 22 2015
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 506 AM MDT MON JUN 22 2015
SHORTWAVE MOVING ALONG THE NORTHERN TIER COMBINED WITH OUTFLOW FROM
MCS ACROSS THE DAKOTAS WILL SEND A FRONT THROUGH SOUTHEAST COLORADO
THIS AFTERNOON. MSAS 3HR PRESSURE CHANGE CHARTS SHOW AROUND 3-5 MB
PRESSURE RISES ACROSS EASTERN WY. HRRR AND NAM12 BRING THE FRONT
INTO NORTHEAST CO AROUND 12Z...WHICH WILL CONTINUE SOUTHWARD INTO
SOUTHEAST COLORADO DURING THE LATE MORNING AND AFTERNOON HOURS.
GUSTY NORTH WINDS WILL SHIFT AROUND FROM THE EAST. INITIALLY WINDS
WILL MIX OUT SHALLOW MOISTURE NEAR THE SURFACE...BUT BY AFTERNOON
SHOULD SEE DEW POINTS INCREASE AGAIN FROM WEST TO EAST AS COOLER AND
MORE STABLE AIRMASS PUSHES IN. ANY POPS TODAY SHOULD STAY CONFINED
TO LOCATIONS ALONG THE FRONT WHICH WILL BE IN THE VICINITY OF THE
RATON MESA REGION...THOUGH STRONG CAP FROM RIDGING ALOFT SHOULD
SUPPRESS ANY CONVECTION UNTIL THE LATE AFTERNOON EARLY EVENING
HOURS. WILL MAINTAIN THE LOW GRADE ISOLATED POPS ACROSS THE
SOUTHERN PORTIONS OF THE SE PLAINS...AS WELL AS THE WETS AND PERHAPS
THE PIKES PEAK REGION. WITH QUITE A BIT OF CIN BEHIND THE
FRONT...THINK ANY THUNDERSTORMS SHOULD DIMINISH QUICKLY AS THEY PUSH
OFF THE MOUNTAINS. EXCEPTION TO THIS MAY BE ALONG THE RATON MESA
REGION WHERE CONVERGENCE MAY BE SUFFICIENT ALONG THE FRONT TO
FIRE/MAINTAIN ONE OR TWO STRONGER STORMS. HOWEVER...DEEP LAYER
SHEARS APPEAR FAIRLY WEAK IN THIS REGION...SO SEVERE THREAT LOOKS
LOW TODAY. TEMPERATURES TODAY WILL BE A CHALLENGE. WENT SLIGHTLY
COOLER FOR THE PLAINS THAN WHAT OCCURRED YESTERDAY...BUT TIMING OF
FRONT WILL MEAN EVERYTHING. TRENDED TOWARDS THE WARMER SIDE OF
CONSENSUS GRIDS...THOUGH NOT AS WARM AS OVERLY WARM MET/MAV GUIDANCE
IS GOING. MEANWHILE...FORECAST PERSISTENCE LOOKS BEST FOR THE
MOUNTAINS AND VALLEYS AS H7 TEMPERATURES ARE PRETTY SIMILAR TO
YESTERDAY.
MODELS DIFFER IN COVERAGE OF THUNDERSTORMS ACROSS THE PLAINS.
ALWAYS LEERY OF A LOW LEVEL JET IN VCNTY OF THE FRONT ACROSS THE
AREA...AS IT COULD GENERATE THUNDERSTORMS NORTH OF THE FRONT WITH
UPGLIDE. HOWEVER...CAP IS QUITE STOUT IN MODEL SOUNDINGS...AND NOT
SURE IF UPGLIDE WILL BE STRONG ENOUGH TO BREACH IT. NAM12 IS PRETTY
DRY...GFS KEEPS ANY SHOWER/THUNDERSTORM POTENTIAL FARTHER TO THE
NORTHEAST...THOUGH DOES HAVE SOME LIGHT QPF OVER THE UPSLOPE REGIONS
OF THE SE MTS. ARW LOOKS FAIRLY DRY...AND NMM PRINTS OUT WHAT LOOKS
LIKE SOME STRATIFORM SHOWERS/LIGHT QPF ACROSS NORTHEAST SECTIONS OF
THE AREA LATE TONIGHT. FOR NOW...KEPT POPS IN THE EVENING ALONG THE
SOUTHERN BORDER OF THE SOUTHEAST PLAINS...WITH SILENT POPS THROUGH
THE NIGHT FOR THE REMAINDER OF THE PLAINS. DID INCREASE SKY COVER
TO ACCOUNT FOR POTENTIAL FOR STRATUS TO DEVELOP ALONG THE SE
MTS/PORTIONS OF THE PLAINS OVERNIGHT. LOWS TONIGHT SHOULD BE COOLER
THAN READINGS THIS MORNING. -KT
.LONG TERM...(TUESDAY THROUGH SUNDAY)
ISSUED AT 506 AM MDT MON JUN 22 2015
SOME ADJUSTMENTS NEEDED DURING THE LONGER TERM WITH PRIMARY
METEOROLOGICAL CONCERNS BEING TEMPERATURES AND POPS...WITH HIGHEST
POTENTIAL OF MORE WIDESPREAD PRECIPITATION EXPECTED FROM FRIDAY
INTO FRIDAY NIGHT.
BY 12Z TUESDAY...UPPER RIDGE LOCATED OVER THE OKLAHOMA/TEXAS
PANHANDLES WILL SHIFT INTO ARKANSAS BY 12Z WEDNESDAY AND THEN
BECOME CENTERED OVER THE SOUTHEASTERN UNITED STATES THROUGH LATE
WEEK WHILE NEXT UPPER RIDGE DEVELOPS OVER THE ARIZONA/UTAH BORDER
FROM LATER THURSDAY INTO THE WEEKEND.
RECENT LONGER TERM COMPUTER SIMULATIONS...PV ANALYSIS AND FORECAST
MODEL SOUNDINGS SUGGEST THAT INCREASED ATMOSPHERIC MOISTURE WILL
DEVELOP OVER MANY SECTIONS OF THE FORECAST DISTRICT FROM LATER
THURSDAY INTO AT LEAST THE EARLY WEEKEND IN COMBINATION WITH
A NORTHEASTERLY TO EASTERLY SURFACE FLOW DEVELOPING ACROSS
EASTERN SECTIONS FROM LATER THURSDAY INTO AT LEAST FRIDAY.
ALSO...UPPER DISTURBANCES WILL BE IMPACTING THE FORECAST
DISTRICT AT TIMES...PRIMARILY FROM LATER THIS WEEK INTO THE
WEEKEND.
INCREASED POPS ARE EXPECTED BY LATER THIS WEEK...MAXIMIZING FROM
FRIDAY INTO FRIDAY NIGHT. IN ADDITION...STRONGER STORMS WILL ALSO
BE POSSIBLE...ESPECIALLY FROM LATER THURSDAY INTO THE WEEKEND AT
LOCALIZED CAPES...LIS AND 0 TO 6 KM BULK SHEARS EXCEED 1500
J/KG...-5C AND 30 KNOTS AT TIMES.
WARMEST CONDITIONS DURING THE LONGER TERM ARE ANTICIPATED FROM
TUESDAY INTO THURSDAY WITH COOLER CONDITIONS THEN EXPECTED FROM
FRIDAY INTO THE WEEKEND.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z TUESDAY MORNING)
ISSUED AT 506 AM MDT MON JUN 22 2015
NORTH WINDS WILL INCREASE AT THE KCOS AND KPUB TAF SITES THIS
MORNING...BEFORE SWINGING AROUND FROM THE EAST TO SOUTHEAST DURING
THE AFTERNOON. GUSTS UP TO 25 KTS WILL BE POSSIBLE ALONG/BEHIND THE
FRONT FOR BOTH LOCATIONS. VFR CIGS/VIS CAN BE EXPECTED...THOUGH
WITH UPSLOPE FLOW TONIGHT...THERE IS THE POTENTIAL FOR SOME STRATUS
TO DEVELOP FOR BOTH TERMINALS LATE TONIGHT THROUGH EARLY TUESDAY
MORNING. CIGS COULD RANGE FROM THE MVFR TO THE IFR CATEGORIES.
KALS WILL REMAIN VFR THROUGH THE PERIOD...WITH BREEZY SOUTHWEST
WINDS AROUND 15 KTS EXPECTED DURING THE AFTERNOON. -KT
&&
.PUB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS MELBOURNE FL
310 PM EDT MON JUN 22 2015
.DISCUSSION...
...CONTINUED HOT WITH LOW RAIN CHANCES ESPECIALLY ALONG THE COAST...
...EXCELLENT BOATING AND BEACH CONDITIONS CONTINUE OVER THE ATLC...
...PATTERN BEGINS TO BREAK DOWN THIS WEEKEND WITH INCREASING RAIN
CHANCES...
CURRENT-TONIGHT...CONDS PRETTY SIMILAR TO SUNDAY WITH A DEARTH OF
DIURNAL CONVECTION THUS FAR. KMLB SHOWS MINIMAL SHOWER ACTIVITY
WHILE KTBW INDICATES A FEW DECENT CELLS ALONG/OUT AHEAD OF THE WCSB.
VISIBLE SATELLITE SHOWS A RATHER SPARSE DIURNAL CU FIELD...PERHAPS
EVEN BIT LESS THAN SUNDAY ON THE EASTERN SIDE OF THE PENINSULA.
THE 17Z HRRR INDICATES THAT THE LATE DAY SEA BREEZE COLLISION WILL
OCCUR OVER LAKE COUNTY...PRETTY CLOSE TO WHERE IT INDICATES THIS
MORNING. GIVEN THE CURRENT LACK OF ECSB ACTIVITY...THE EVENING FCST
WHICH KEEPS PRECIP CONFINED TO WEST OF THE ST JOHNS RIVER WILL
SUFFICE...AND WILL NOT NEED TO RUN WITH A PRE-FIRST PERIOD FOR THIS
CYCLE. DON`T EXPECT A REPEAT OF THIS MORNING`S EARLY FLAREUP AS THE
MID LEVEL REFLECTION OF THE ATLC RIDGE SHOULD KEEP THE WEAK VORT
OUT OVER THE EASTERN GOMEX. WENT WITH A TEMPERATURE SPREAD SIMILAR TO
LAST NIGHT...MOSTLY M-U70S...WITH A FEW L70S AT THE USUAL SHELTERED
ASOS SITES WHICH LIE BENEATH THE SFC RIDGE AXIS.
TUE-WED...LITTLE CHANGE TO THE CURRENT SYNOPTIC PATTERN AS DEEP
LAYER RIDGING REMAINS OVERHEAD. ONE INTERESTING NOTE IS THE GFS
SHOWS SOME SUBTLE ENHANCEMENT OF A RIBBON OF H50 VORTICITY ACROSS THE
CENTRAL AND NORTHERN CWA BY WED. NOT ENTIRELY SURE OF THE VERACTIY
OF THIS FEATURE CONSIDERING NEITHER THE ECM NOR THE NAM SHOW THIS.
CONSEQUENTLY...FORECAST IS PRETTY MUCH PERSISTENCE AS LIGHT SSE TO
SW SFC FLOW ABOUT THE RIDGE AXIS REMAINS IN PLACE. ECSB WILL FORM
AND MOVE STEADILY INLAND...WITH A SLIGHTLY FASTER/FARTHER INLAND
PUSH INLAND FROM THE TREASURE COAST. MAX/MIN TEMPS REMAIN WHERE
THEY`VE BEEN THE PAST SEVERAL DAYS...GENERALLY IN THE L90S AT THE
COAST AND M90S INLAND....A FEW U90S IN NORMALLY HOTTER LOCALES. MINS
GENERALLY IN THE M-U70S...A FEW L70S NEAR THE RIDGE AXIS.
THU-MON (MODIFIED PREV)...A WELCOME TREND FOR INCREASING RAIN CHCS
(ESPECIALLY FOR THE FL EAST COAST) IS EXPECTED FROM LATE WEEK INTO
THIS WEEKEND AS THE ZONAL JET BRINGS THE NEXT SHORT WAVE TROF ACRS
THE UPR MIDWEST/GREAT LAKES REGION EN ROUTE FOR NEW ENGLAND AND THE
MID ATLC FOR THE WEEKEND. WHILE THE TROF WILL HAVE LITTLE CHANCE OF
UPROOTING THE DEEPLY ENTRENCHED ATLC RIDGE THRU WEEK`S END...IT WILL
BE ABLE TO SUPPRESS ITS AXIS BACK TO THE SOUTH.
BOTH GFS/ECMWF MODELS INDICATE THE LOW LEVEL RIDGE AXIS REMAINING
OVER THE CTRL-SRN CWA...BEFORE DRIFTING SWD INTO SOUTH FL THRU THE
WEEKEND. THE RESULTING H100-H70 FLOW WILL SHIFT TO THE S BY SUNSET
THU...THEN TO THE SW BY DAYBREAK SAT...RESULTING IN A GRADUAL SHIFT
OF HIGHEST DIURNAL POPS FROM THE INTERIOR COUNTIES BACK TO THE E FL
COAST. TEMPS NEAR OR SLIGHTLY ABV AVG WITH MAXES L/M90S...MINS
L/M70S.
SFC AND MID LEVEL TROUGHS DEEPEN FURTHER ACROSS NORTH FL BY MON...
WHICH WILL LIKELY PORTEND EVEN HIGHER RAIN CHANCES NEXT MONDAY.
&&
.AVIATION...ECSB MAY GET WEST OF THE MCO-SFB CORRIDOR WITHOUT MUCH
FANFARE. LIKE SUNDAY..COLLISION TOWARD 00Z WILL GIVE BEST CHC FOR
SHRA/TS INVOF THE KLEE-KISM AERODROMES THROUGH ABOUT 02Z.
&&
.MARINE...TUE-SAT...STEADY STATE CONDITIONS THRU THE UPCOMING WEEK.
ATLC RIDGE AXIS WILL REMAIN OVER THE FL PANHANDLE/NRN PENINSULA THRU
MIDWEEK...MAINTAINING A GENTLE TO MODERATE SW TO SE BREEZE ABOUT THE
RIDGE AXIS. WINDS WILL BECOME SERLY EACH AFTERNOON NEAR SHORE IN THE
LOCAL SEA BREEZE CIRC. WINDS VEER MORE TO THE SW BY THIS WEEKEND AS
THE RIDGE AXIS DRIFTS INTO SOUTH FL AHEAD OF AN APPROACHING FRONTAL
TROUGH.
LOCAL WAVE MODEL GUIDANCE CONTINUES TO AVERAGE ABOUT A FT TOO HIGH
OVER MOST OF THE MAOR. WHILE THE FCST CONTINUES TO ADVERTISE SEAS
MAINLY IN THE 2-3FT RANGE FROM TUE ONWARD...IT HAS BEEN SHOWING 2-
3FT SINCE SATURDAY...AND HAS HAD TO BE PARED BACK TO 1-2FT SEVERAL
CYCLES IN A ROW. CONSEQUENTLY...SEAS WILL LIKELY WIND UP BEING 2FT
OR LESS.
&&
.CLIMATE...DAYTONA BEACH INT`L APRT TIED THEIR RECORD HIGH OF 96F
WHICH WAS ORIGINALLY SET IN 2009. ORLANDO INT`L MAY COME WITHIN A
DEGREE OR TWO OF THEIR RECORD...WHILE THE RECORD HIGHS ARE SAFE
ELSEWHERE.
RECORD HIGHS FOR TODAY JUNE 22ND...
DAYTONA BEACH 96 IN 2009. (TIED TODAY)
ORLANDO INTL 98 IN 1987.
MELBOURNE 99 IN 2009.
VERO BEACH 102 IN 2009.
&&
.PRELIMINARY POINT TEMPS/POPS...
DAB 77 93 76 92 / 20 20 10 20
MCO 78 95 75 95 / 20 30 30 30
MLB 76 91 76 91 / 10 20 10 20
VRB 75 91 74 92 / 10 20 10 20
LEE 78 96 78 94 / 40 30 40 30
SFB 78 95 76 94 / 20 30 20 30
ORL 78 95 77 94 / 20 30 30 30
FPR 74 91 73 92 / 10 20 10 20
&&
.MLB WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
AM...NONE.
&&
$$
PUBLIC FORECASTS...CRISTALDI
RADAR/AVIATION/IMPACT WX...MOSES
AREA FORECAST DISCUSSION
NWS MELBOURNE FL
945 AM EDT MON JUN 22 2015
.UPDATE...
...ABOVE NORMAL TEMPERATURES WILL CONTINUE TO START OFF THE WEEK
WITH HIGHEST RAIN CHANCES OVER THE INTERIOR...
SFC AND MID LEVEL RIDGES ARE NOW PRETTY WELL ALIGNED/STACKED THIS
MORNING...WITH THEIR AXES NEAR A KVRB-KZPH LINE. WHILE CONDS ARE
QUITE OVER ECFL...IT WAS A CONVECTIVELY ACTIVE EARLY MORNING ON THE
WEST SIDE OF THE PENINSULA. HIGHER STORM COVERAGE COMPARED TO
SATURDAY...WHICH WAS THE MORE ACTIVE OF THE TWO WEEKEND DAYS. STORMS
HAVE WEAKENED SOME SINCE 09Z-12Z...WITH A PRETTY COOL LOOKING UPPER
TROPOSPHERIC GRAVITY WAVE SIGNATURE EMANATING FROM THE CONVECTION...
WHICH HAS WEAKENED IN THE LAST HOUR OR SO.
MORNING RAOBS SHOW SIMILAR PWAT VALUES TO SUNDAY (1.8") WHICH WAS A
FAIRLY INACTIVE DAY...HOWEVER RH VALUES APPEAR TO BE A LITTLE HIGHER
BTWN H85 AND H70. TEMPS ALOFT HAVE COOLED A LITTLE...ABOUT 0.5C THRU
THE H50-H85 LAYER. VIS SATELLITE SHOWS CU FIELD IS DEVELOPING LITTLE
EARLIER AND IS MORE ROBUST ALONG THE TREASURE COAST COMPARED TO SUN.
GIVEN SLIGHT NWD SHIFT OF LOW LEVEL RIDGE AXIS...EXPECT EAST COAST
SEA BREEZE TO DEVELOP AND MOVE INLAND JUST A BIT FASTER ALONG THE
TREASURE COAST TODAY COMPARED TO VOLUSIA/BREVARD. NOT MUCH TO
QUIBBLE WITH IN THE GRIDS...MAY STRETCH THE SLGT CHC A HAIR CLOSER
TO THE COAST....BUT THAS`S ABOUT IT. TEMPS LOOK FINE...L-M90S OVER
THE COASTAL COS AND 95-96F INLAND...A FEW U90S IN NORMALLY HOTTER
LOCALES.
&&
.AVIATION...SPOTTY MVFR CIGS BKN020-030 PSBL MLB-SUA AS DIURNAL CU
FIELD DEVELOPS IN ADVANCE OF ECSB. ISOLD SHRA/TS PSBL...BUT LIKELY
WEST OF THE COASTAL AERODROMES. 12Z HRRR SUGGEST BEST CHC FOR TS
NEAR LATE DAY COLLISION NEAR KLEE-KISM.
&&
.MARINE...LIGHT WIND FLOW AOB10KT ABOUT SFC RIDGE AXIS...S-SE TO THE
SOUTH OF SEBASTIAN INLET...AND S-SE TO THE NORTH. LOCAL SEA BREEZE
CIRC WILL TURN WINDS ONSHORE ALL AREAS NEAR SHORE BY THIS AFTERNOON.
BASED UPON CURRENT BUOY OBS...WILL CAP SEAS AT 2FT THROUGH TONIGHT.
FOR SEVERAL DAYS NOW BOTH THE WNA AND NWPS HAVE BEEN SHOWING AREAS
OF 3FT SEAS OFFSHORE THAT HAVE FAILED TO DEVELOP...AND AS THERE IS
NOTHING IN THE BUOY DATA TO SUGGEST HIGHER SEAS CREEPING INTO THE
CWA ATTM.
&&
UPDATE...CRISTALDI
RADAR/AVIATION...MOSES
&&
.PREV DISCUSSION... /ISSUED 415 AM EDT MON JUN 22 2015/
TUE-WED...
ZONAL JET PATTERN OVER THE NRN TIER STATES WILL PERSIST INTO
MIDWEEK. THE JET WILL PUSH A WEAK H100-H70 CYCLONE OVER NEW ENGLAND
INTO THE N ATLC...FORCING IT TO ABANDON ITS SRN TROF EXTENSION OVER
THE MID ATLC. THIS LATTER FEATURE WILL DAMPEN OUT BY DAYBREAK
TUE...ALLOWING THE ATLC RIDGE AXIS TO REBUILD OVER THE FL
PANHANDLE/DEEP SOUTH. H30-H20 JET ACTIVITY OVER THE SRN TIER STATES
IS ALMOST NON EXISTENT AND SHOWING NO SIGNS OF UNDERGOING ANY
SIGNIFICANT STRENGTHENING THRU MIDWEEK.
LATEST STREAM LINE ANALYSIS OF THE H100-H70 LYR OVER THE TROPICAL
ATLC REVEALS NO MEANINGFUL ERLY WAVE ACTIVITY OUT TO PUERTO RICO...
SUGGESTING THAT ONCE THE RIDGE AXIS LIFTS N THE RESULTING E/SE
STEERING FLOW WILL REMAIN ON THE WEAK SIDE...BUT STILL DEEP ENOUGH
TO PROMOTE THE EARLY FORMATION OF THE EAST COAST SEA BREEZE WHILE
SIMULTANEOUSLY FOCUSING DIURNAL CONVECTION OVER THE WRN HALF OF THE
PENINSULA.
BAHAMAS/HISPANIOLA WILL BE SOURCE REGION ONCE THE RIDGE LIFTS
NWD...AN AREA CURRENTLY SHOWING SIGNIFICANT SUPPRESSION DUE TO THE
PRESENCE OF A CLOSED TUTT CIRCULATION N OF PUERTO RICO.
FURTHERMORE...WATER VAPOR IMAGERY SHOWS SIG UPR LVL MOISTURE ACRS
THE DEEP SOUTH/GOMEX REGION THAT WILL LEND ITSELF TO THE FORMATION
OF MID/UPR LVL DEBRIS CLOUDS THAT WOULD TEND TO DELAY SFC HEATING
ACRS THE FL PENINSULA. INDEED...WHILE MODEL SOUNDINGS INDICATE PWAT
VALUES GENERALLY IN THE 1.7"-1.9" RANGE OVER MOST OF THE CWA... MUCH
OF IT IS TRAPPED IN AN H40-H20 SATURATION LYR WHILE THE H85-H50
SHOWS A SIGNIFICANT AMT OF DRY AIR.
WITH SATURATED UPR LYRS...DRY MID LYRS...AND LIGHT BUT DEEP ERLY
FLOW...POPS WILL BE ON THE LOW SIDE. WILL GO WITH THE USUAL
EAST/WEST DISTRIBUTION...KEEPING 20/10 POPS IN FOR THE COAST AND
30/20 INTERIOR THRU THE DAY/EVNG HRS RESPECTIVELY. TEMPS CONT ABV
AVG WITH MAXES IN THE L90 ALONG THE COAST AND M90S INTERIOR...MINS
L/M70S AREAWIDE.
THU-SUN...
INCREASING PRECIP TREND THRU THE LATTER HALF OF THE WEEK AS THE
ZONAL JET BRINGS THE NEXT SHORT WAVE TROF ACRS THE UPR MIDWEST/GREAT
LAKES REGION EN ROUTE FOR NEW ENGLAND AND THE MID ATLC FOR THE
WEEKEND. WHILE THE TROF WILL HAVE LITTLE CHANCE OF UPROOTING THE
DEEPLY ENTRENCHED ATLC RIDGE THRU WEEK`S END...IT WILL BE ABLE TO
SUPPRESS ITS AXIS BACK TO THE S.
BOTH GFS/ECMWF MODELS INDICATE THE AXIS DRIFTING ACRS CENTRAL FL
THRU THE THU/FRI TIME FRAME...THEN INTO S FL THRU THE WEEKEND. THE
RESULTING H100-H70 FLOW WILL SHIFT TO THE S BY SUNSET THU...THEN TO
THE SW BY DAYBREAK SAT...RESULTING IN A GRADUAL SHIFT OF HIGHEST
DIURNAL POPS FROM THE INTERIOR COUNTIES BACK TO THE E FL COAST.
TEMPS NEAR OR SLIGHTLY ABV AVG WITH MAXES L/M90S...MINS L/M70S.
&&
.AVIATION...
ISOLATED SHRA/TSRA SHOULD DEVELOP JUST WEST OF KSFB-KMCO CORRIDOR
AND MOVE WEST TWD KLEE BY 22Z-02Z AND BECOME SCATTERED THIS EVENING.
MAINLY VFR OUTSIDE OF CONVECTION TODAY. SHOULD BE MAINLY DRY FOR
CSTL TERMINALS THOUGH MAY SEE SOME CONVECTION TRY TO MAKE IT BACK
TWD KDAB VCNTY THIS EVENING.
&&
.MARINE...
TODAY-TONIGHT...S/SW WINDS THIS MORNING WILL VEER TO THE SE THIS
AFTERNOON INTO TONIGHT WITH SPEEDS TO 10-15 KNOTS. SEAS 1-2 FT
TODAY WILL BUILD TO 2-3 FT TONIGHT.
TUE-FRI...STEADY STATE CONDITIONS THRU THE UPCOMING WEEK. ATLC RIDGE
AXIS WILL REMAIN OVER THE FL PANHANDLE/NRN PENINSULA THRU MIDWEEK...
MAINTAINING A GENTLE TO MODERATE SERLY BREEZE THRU MID WEEK. WINDS
WILL VEER SLIGHTLY TO THE S/SW INTO WEEK`S END AS A FRONTAL TROF
PRESSES INTO THE MIDWEST/NEW ENGLAND REGION AND SUPPRESSES THE RIDGE
AXIS INTO THE CENTRAL FL PENINSULA. SEAS 2-3FT THRU THE UPCOMING
WEEK...OCNL 4FT IN THE GULF STREAM.
&&
.CLIMATE...
IT DOES NOT LOOK LIKE RECORDS WILL BE BROKEN AT ANY OF OUR CLIMATE
SITES BUT HIGH TEMPS MAY COME WITHIN A ONE TO TWO DEGREES AT DAYTONA
BEACH AND ORLANDO.
RECORD HIGHS FOR TODAY...
DAYTONA BEACH 96 IN 2009.
ORLANDO INTL 98 IN 1987.
MELBOURNE 99 IN 2009.
VERO BEACH 102 IN 2009.
&&
.MLB WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
AM...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS LINCOLN IL
305 PM CDT MON JUN 22 2015
.SHORT TERM...(TONIGHT)
ISSUED AT 304 PM CDT MON JUN 22 2015
SURFACE ANALYSIS THIS AFTERNOON SHOWING THE COLD FRONT WELL OFF TO
THE NORTHWEST OVER NW IA THIS AFTERNOON. OUTFLOW BOUNDARY FROM THE
MCS THIS MORNING AND AFTERNOON OVER NRN IL STILL MAKING ITS WAY
ACROSS THE STATE AND CLEARLY VISIBLE ON SAT IMAGERY. RAPP/RUC AND
HRRR STILL REDEVELOPING THE PRECIPITATION/TS ALONG THE BOUNDARY THIS
AFTERNOON. SAME SHORT TERM MODELS BRINGING PRECIP LATER AFTER 00Z
IN THE EXTREME WEST AND SPREADING OVER MUCH OF THE AREA WEST OF I-55
BEFORE 04Z. STILL LOOKS TO BE MORE SCATTERED FURTHER TO THE
EAST...AND NARROW EITHER WAY. NOT MUCH OF A SHIFT IN THE OVERNIGHT
GRIDS OVERALL. SOME CONCERN WITH WIND THREAT WITH THUNDERSTORMS
TONIGHT AND EVENTUALLY HAIL AS THE COLDER AIRMASS GETS CLOSER. SO
FAR, PRECIP HAS FIRED JUST AHEAD OF THE COLD FRONT, SO TIMING MAY
BECOME AN ISSUE SHOULD THE SHOWERS MAINTAIN.
&&
.LONG TERM...(TUESDAY THROUGH MONDAY)
ISSUED AT 304 PM CDT MON JUN 22 2015
OUTFLOW BOUNDARY AND COLD FRONT FROM TONIGHTS MCS/SEVERE WEATHER
WILL LIKELY PUSH THROUGH THE CWA AND END UP SOMEWHERE IN SOUTHERN
IL. SO POPS WILL CONTINUE ACROSS SOUTHEASTERN PARTS OF THE CWA
TUESDAY. THIS BOUNDARY/FRONT WILL NOT STAY SOUTH VERY LONG AND THEN
WILL BEGIN TO LIFT BACK NORTHWARD THROUGH THE AREA AND THEN BECOME
SOMEWHAT STATIONARY OVER THE AREA AS A SERIES OF MCS`S MOVE ACROSS
THE AREA THROUGH MOST OF THE WEEK. CHANCE OF STORMS WILL REMAIN IN
THE FORECAST THROUGH FRIDAY. SEVERE WEATHER WILL BE POSSIBLE ANY DAY
DURING THE WEEK WITH LOTS OF MOISTURE AND A FRONT IN THE AREA.
LOCATION OF POSSIBLE SEVERE WEATHER IS VERY UNCERTAIN. THEN A
STRONGER HIGH PRESSURE AREA WILL FINALLY PUSH THE FRONT SOUTH ENOUGH
THAT DRIER WEATHER WILL BE FELT IN THE CWA FOR THE NORTHERN HALF OF
THE AREA FRIDAY NIGHT/MOST OF THE AREA SATURDAY/AND WHOLE AREA SAT
NIGHT. THUNDERSTORMS CHANCES RETURN IN THE NORTH FOR SUN AND SUN
NIGHT AND THEN THE WHOLE AREA FOR MONDAY.
TEMPS THROUGH THUR WILL REMAIN WARM UNTIL THE FRONT PUSHES SOUTH OF
THE AREA LATE IN THE WEEK. THEN COOLER TEMPS WILL BE SEEN FOR FRIDAY
THROUGH MONDAY.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON)
ISSUED AT 1244 PM CDT MON JUN 22 2015
SHORT TERM MODELS LIKE RUC/RAPP AND THE HRRR ARE STILL SHUNTING
THE MAJORITY OF THE PRECIP/CONVECTION OFF TO THE NORTH AND EAST OF
THE ILX TERMINALS. INSTEAD OF DEVELOPMENT ALONG THE OUTFLOW THAT
IS CURRENTLY MAKING ITS WAY THROUGH THE REGION, THE MODELS
CONTINUE TO KEY IN ON DEVELOPMENT ALONG THE COLD FRONT AS IT
SETTLES INTO THE REGION TONIGHT. THE BETTER CHANCES TO SEE ACTUAL
CONVECTION AT THIS POINT IS CLOSER TO PIA, AND HAVE ADDED A TEMPO
TO REFLECT THAT, WITH A VCTS FOR THE REMAINING TAF SITES. VFR FOR
MOST LOCATIONS, WITH THE TS TEMPO WITH AN MVFR VIS.
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...HJS
LONG TERM...AUTEN
AVIATION...HJS
AREA FORECAST DISCUSSION
NWS LINCOLN IL
1248 PM CDT MON JUN 22 2015
.UPDATE...
ISSUED AT 1042 AM CDT MON JUN 22 2015
LOW PRESSURE CENTER MOVING INTO THE UPPER MIDWEST THIS MORNING
WITH A MCS OVER SRN WI AND NORTHERN IL. SHORT TERM MODELS HAVE
BEEN RATHER CONSISTENT WITH LIMITING PRECIP ALONG ANY
OUTFLOW...INSTEAD FIRING PRECIP ALONG THE COLD FRONT LATER
TONIGHT. AS A RESULT, THE POPS REMAIN LOW IN THE NORTHERN TIER.
WITH THE BULK OF THE CONVECTION AND SUBSEQUENT CLOUD COVER PUSHED
TO THE NORTH, TEMPERATURES ARE WELL ON THEIR WAY INTO THE LOWER
90S AND NO UPDATES ARE ANTICIPATED AT THIS TIME.
&&
.SHORT TERM...(TODAY)
ISSUED AT 318 AM CDT MON JUN 22 2015
08Z/3AM SURFACE ANALYSIS SHOWS WARM FRONT LIFTING SLOWLY NORTHWARD
THROUGH THE AREA. MOST HIGH-RES MODEL SOLUTIONS SUGGEST WIDELY
SCATTERED CONVECTION WILL DEVELOP ALONG/AHEAD OF THE BOUNDARY OVER
THE NEXT COUPLE OF HOURS BEFORE SHIFTING INTO NORTHERN ILLINOIS BY
MID-MORNING. HAVE THEREFORE INCLUDED SLIGHT CHANCE POPS
ALONG/NORTH OF I-74 THROUGH 15Z. FURTHER NORTHWEST...A LARGE
COMPLEX OF THUNDERSTORMS IS CURRENTLY DEVELOPING OVER SOUTH
DAKOTA. THESE STORMS ARE GENERALLY TRACKING EASTWARD AND WILL
LIKELY STAY WELL NORTH OF THE KILX CWA. WILL HOWEVER NEED TO KEEP
A CLOSE EYE ON THEIR EVOLUTION...AS CORFIDI VECTORS SUGGEST A
SLIGHT TURN TO THE SOUTHEAST AS THEY APPROACH THE GREAT LAKES
LATER THIS MORNING. DUE TO UNCERTAINTY REGARDING THE EXACT TRACK
OF THIS COMPLEX...HAVE MAINTAINED SLIGHT CHANCE POPS ACROSS THE
FAR NORTHERN CWA THROUGH MIDDAY. AFTER THAT...ATTENTION TURNS TO
AN APPROACHING COLD FRONT THAT COULD POTENTIALLY TRIGGER A LINE OF
STRONG TO SEVERE THUNDERSTORMS LATER TODAY INTO TONIGHT. ALL
MODELS SHOW STORMS DEVELOPING ALONG THE FRONT ACROSS EASTERN
IOWA LATE...HOWEVER SOME MINOR TIMING DIFFERENCES EXIST. 12KM
NAM/4KM NAM/RAPID REFRESH ALL KEEP CONVECTION NORTHWEST OF THE
AREA UNTIL EVENING...WHILE THE 4KM WRF AND SREF ARE SLIGHTLY
FASTER AND POTENTIALLY BRING IT INTO THE FAR NW CWA AROUND
GALESBURG BY LATE AFTERNOON. HAVE INCLUDED SLIGHT CHANCE POPS
NORTHWEST OF THE ILLINOIS RIVER AFTER 21Z ACCORDINGLY...WITH
BETTER STORM CHANCES HOLDING OFF UNTIL EVENING. OUTSIDE OF THE
SLIM STORM CHANCES TODAY...THE MAIN WEATHER STORY WILL BE THE
WINDY AND HOT CONDITIONS. ONCE THE WARM FRONT LIFTS
NORTHWARD...SOUTHWESTERLY WINDS WILL GUST TO BETWEEN 25 AND 30 MPH
THIS AFTERNOON WITH HIGH TEMPERATURES SOARING INTO THE LOWER 90S.
.LONG TERM...(TONIGHT THROUGH SUNDAY)
ISSUED AT 318 AM CDT MON JUN 22 2015
LINE OF CONVECTION WILL PUSH INTO WEST-CENTRAL ILLINOIS DURING THE
EVENING HOURS...REACHING A BLOOMINGTON TO JACKSONVILLE LINE BY MID
TO LATE EVENING. AIRMASS WILL INITIALLY BE CAPPED ALONG/AHEAD OF
THE FRONT...BUT MODELS SHOW THE CAP WEAKENING BY LATE
AFTERNOON/EVENING AS SHORT-WAVE TROUGH APPROACHES FROM THE WEST.
ONCE CAP IS BROKEN...GOOD CONVERGENCE ALONG THE FRONT WILL INTERACT
WITH A STRONGLY UNSTABLE AND SHEARED ENVIRONMENT TO PRODUCE STRONG
TO POTENTIALLY SEVERE THUNDERSTORMS. LARGE HAIL AND DAMAGING WIND
GUSTS WILL BE THE PRIMARY THREATS. HAVE BOOSTED POPS TO LIKELY
ALONG/NORTH OF I-72 DURING THE EVENING ACCORDINGLY. STORMS WILL
TEND TO WEAKEN AS THEY TRACK FURTHER E/SE OVERNIGHT...SO HAVE
DECREASED POPS AFTER MIDNIGHT.
FRONT WILL DROP INTO SOUTHERN ILLINOIS ON TUESDAY...PROVIDING A
BREAK FROM THE HEAT AND RAIN CHANCES. WILL MAINTAIN LOW CHANCE POPS
ALONG/SOUTH OF A TAYLORVILLE TO MARSHALL LINE...WITH DRY WEATHER
FURTHER NORTH ACROSS THE REMAINDER OF THE AREA. WILL BE SEVERAL
DEGREES COOLER...WITH HIGHS RANGING FROM THE LOWER 80S NORTH TO THE
UPPER 80S FAR SOUTH. FRONT WILL BEGIN LIFTING BACK NORTHWARD
TUESDAY NIGHT INTO WEDNESDAY...SO HAVE SPREAD POPS BACK ACROSS THE
ENTIRE AREA. BEST FORCING FOR PRECIP WILL BE FOCUSED ALONG/WEST OF
THE MISSISSIPPI RIVER...SO HAVE GONE WITH HIGHEST POPS IN THE
ILLINOIS RIVER VALLEY...TAPERING DOWN TO JUST LOW CHANCE ALONG THE
INDIANA BORDER.
WITH THE FRONTAL BOUNDARY WAVERING IN THE VICINITY FOR SEVERAL
DAYS...RAIN CHANCES WILL CONTINUE FOR BOTH THURSDAY AND FRIDAY
BEFORE COOLER/DRIER CONDITIONS ARRIVE BY THE WEEKEND. ALL MODELS
DEVELOP A STRONG UPPER RIDGE OVER THE ROCKIES/GREAT BASIN BY THE END
OF THE WEEK...RESULTING IN A SIGNIFICANT DOWNSTREAM TROUGH OVER THE
GREAT LAKES/MIDWEST. 12Z ECMWF HAD FEATURED A PROMINENT SURFACE LOW
IN THE BASE OF THE TROUGH...WHICH WOULD HAVE KEPT RAIN CHANCES ALIVE
INTO THE WEEKEND...HOWEVER THE 00Z RUN HAS DROPPED THAT SOLUTION IN
FAVOR OF THE DRY GFS/GEM CONSENSUS. AS A RESULT...AM GOING WITH A
DRY FORECAST SATURDAY THROUGH MONDAY WITH TEMPERATURES DROPPING INTO
THE UPPER 70S AND LOWER 80S.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON)
ISSUED AT 1244 PM CDT MON JUN 22 2015
SHORT TERM MODELS LIKE RUC/RAPP AND THE HRRR ARE STILL SHUNTING
THE MAJORITY OF THE PRECIP/CONVECTION OFF TO THE NORTH AND EAST OF
THE ILX TERMINALS. INSTEAD OF DEVELOPMENT ALONG THE OUTFLOW THAT
IS CURRENTLY MAKING ITS WAY THROUGH THE REGION, THE MODELS
CONTINUE TO KEY IN ON DEVELOPMENT ALONG THE COLD FRONT AS IT
SETTLES INTO THE REGION TONIGHT. THE BETTER CHANCES TO SEE ACTUAL
CONVECTION AT THIS POINT IS CLOSER TO PIA, AND HAVE ADDED A TEMPO
TO REFLECT THAT, WITH A VCTS FOR THE REMAINING TAF SITES. VFR FOR
MOST LOCATIONS, WITH THE TS TEMPO WITH AN MVFR VIS.
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...HJS
SHORT TERM...BARNES
LONG TERM...BARNES
AVIATION...HJS
AREA FORECAST DISCUSSION
NWS LINCOLN IL
1159 PM CDT SUN JUN 21 2015
.UPDATE...
ISSUED AT 900 PM CDT SUN JUN 21 2015
TREND FOR THE REST OF THE NIGHT IS FOR DRY CONDITIONS UNTIL LATE
TONIGHT. HRRR AND RAP OUTPUT BOTH SHOW INCREASING CHANCES AFTER
09Z. THERE IS SOME INDICATION OF A LINE OF SHOWERS DEVELOPING NEAR
SPI AND EXTENDING IN A NW TO SE LINE AS THEY MOVE NORTHEAST ACROSS
OUR AREA. THE SHOWERS APPEAR TO BE SPOTTY, AND MOST AREAS SHOULD
REMAIN DRY. WE REDUCED POPS THIS EVENING IN ALL AREAS, AND KEPT A
GRADUAL INCREASE OF POPS AFTER MIDNIGHT.
THE HRRR IS ADVERTISING A STRONG MCS ROLLING ACROSS NORTHERN IOWA
TONIGHT AND REACHING NORTHERN IL BETWEEN 12Z-14Z. THE RAP SHOWS
INCREASE COVERAGE OF STORMS IN OUR WESTERN CWA, WITH A WAVE
APPROACHING FROM THE NW LATE TONIGHT, BUT NOT NEARLY AS VIGOROUS
AS THE HRRR. THE HRRR TRACK SHOWS THE STRONGEST STORMS SHOULD
REMAIN NORTH OF OUR COUNTIES TOMORROW MORNING, BUT SPC HAS KEPT US
IN A MARGINAL RISK FOR SEVERE STORMS (5%) NORTH OF PEORIA.
SATELLITE IMAGES SHOW A THIN LAYER OF HIGH CLOUDS WILL LIKELY
COVER ALL BUT THE NORTHERN COUNTIES FOR MUCH OF THE NIGHT. THE
INSULATING EFFECT OF THE CLOUDS AND HIGH SURFACE DEWPOINTS SHOULD
HELP TO KEEP LOWS IN THE UPPER 60S TO LOW 70S. LIGHT FOG COULD
DEVELOP IN LOW LYING AREAS, AS SURFACE WINDS REMAIN LIGHT THE REST
OF THE NIGHT.
&&
.SHORT TERM...(TONIGHT)
ISSUED AT 259 PM CDT SUN JUN 21 2015
MCS WITH SHOWERS AND THUNDERSTORMS OVER CENTRAL MO AND DEVELOPING
EASTWARD INTO SW HALF OF IL WITH THUNDERSTORMS AS FAR EAST AS
EASTERN SHELBY COUNTY. DIURNALLY INDUCED INSTABILITY AS CAPES
RISING INTO THE 1500-3000 J/KG RANGE AND HIGHEST OVER OVER SW CWA
AT MID AFTERNOON. CAPES RISE TO 4000 J/KG AND HIGHER OVER CENTRAL
AND WESTERN MO AND 4000-6000 J/KG FURTHER WEST OVER KS. SOME CIN
RESTRICTING CONVECTION DEVELOPMENT OVER SOUTHEAST IL BUT THAT IS
FADING AND EXPECT SCATTERED CONVECTION TO DEVELOP THERE AS WELL
LATE THIS AFTERNOON/EARLY EVENING. AN OLD OUTFLOW BOUNDARY EXTENDS
FROM FAR NORTHERN MO INTO FAR SW IL CLOSER TO MS RIVER VALLEY.
EXPECT THE BOUNDARY TO GRADUALLY SHIFT BACK NORTHWARD LATE THIS
AFTERNOON AND INTO TONIGHT ACROSS CENTRAL AND EVENTUALLY NORTHERN
IL WITH UPPER LEVEL SHORT WAVE CURRENT TRACKING EAST SOUTHEAST
ACROSS THE NORTHERN PLAINS. HAVE LIKELY CHANCES OF SHOWERS AND
THUNDERSTORMS OVER SW CWA THIS AFTERNOON INTO EARLY EVENING AND
THEN TAPERS TO SLIGHT CHANCES FROM I-74 NE. OUR NE CWA FROM I-74
NE TO SEE THERE BEST CHANCES OF SHOWERS AND THUNDERSTORMS AFTER
SUNSET TONIGHT. SPC CONTINUES SLIGHT CHANCE OF SEVERE STORMS FROM
RUSHVILLE TO TERRE HAUTE SW REST OF THIS AFTERNOON AND INTO THIS
EVENING WHILE ENHANCED RISK IS FURTHER SW OF CWA OVER CENTRAL MO
INTO SW IL WHERE AIRMASS IS MORE UNSTABLE. LOCALLY HEAVE RAIN
POSSIBLE SW CWA AS WELL WITH PRECIPITABLE WATER VALUES RANGING
FROM 1.5-2 INCHES WHILE AROUND 2 INCHES OVER PARTS OF CENTRAL MO.
MUGGY LOWS TONIGHT IN THE LOWER 70S WITH A FEW UPPER 60S NE OF
I-74.
.LONG TERM...(MONDAY THROUGH SUNDAY)
ISSUED AT 259 PM CDT SUN JUN 21 2015
LOOKS LIKE WE WILL GET A BRIEF BREAK FROM THE CHANCE OF SHOWERS AND
STORMS MONDAY AS THE FRONTAL BOUNDARY WILL LIFT BACK NORTH DURING
THE MORNING AND THEN BE ACROSS NORTHERN IL OR EVEN SOUTHERN WI. BUT
WE WILL KEEP A SMALL CHANCE OF PCPN IN MONDAY IN THE EXTREME NORTH
PARTS OF THE CWA. UNFORTUNATELY THIS WILL NOT LAST LONG AS ANOTHER
COLD FRONT WILL DROP THROUGH THE AREA MONDAY NIGHT WITH MORE SHOWERS
AND THUNDERSTORMS. THIS FRONT WILL LIKELY NOT DROP TOO FAR AND
BECOME QUASI-STATIONARY OVER THE SOUTHERN HALF OF ILLINOIS FOR
TUESDAY AND TUESDAY NIGHT. SO PCPN CHANCES WILL CONTINUE IN THE
SOUTHEAST FOR TUE AND THEN OVER THE WHOLE AREA FOR TUE NIGHT AS
ANOTHER POSSIBLE MCS DEVELOPS WEST OF THE AREA AND ROLLS INTO IL FOR
TUE NIGHT INTO WED. ANY OUTFLOW BOUNDARY WILL BE OVER THE AREA WED
NIGHT AND THUR THUS CONTINUING THE CHANCES OF SHOWERS AND STORMS
THROUGH THUR. FOR THE REMAINDER OF THE WEEK AND INTO THE WEEKEND...A
FRONTAL BOUNDARY WILL REMAIN OVER THE AREA...WHICH WILL KEEP THE
CHANCE OF SHOWERS AND STORMS IN THE AREA THROUGH THE END OF THE WEEK
AND INTO THE WEEKEND.
TEMPS WILL BE QUITE WARM THROUGH THUR AND WITH DEWPOINTS IN THE
LOWER 70S HEAT INDEX VALUES WILL GET INTO THE 95 TO 100 RANGE ON
MONDAY AND WED. THIS WORTH NOTING...BUT NOT ENOUGH FOR A HEAT
ADVISORY. A COLD FRONT WILL SLIDE THROUGH THE AREA LATER IN THE WEEK
AND THEN SHOULD BRING COOLER TEMPS TO THE REGION FOR FRIDAY THROUGH
SUNDAY.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT)
ISSUED AT 1159 PM CDT SUN JUN 21 2015
THE 03Z/10PM SURFACE ANALYSIS SHOWS THE STATIONARY FRONT EXTENDING
ACROSS SOUTHERN IL. STRONG STORMS HAVE JUST RECENTLY DEVELOPED NORTH
OF THE BOUNDARY IN OUR COUNTIES ALONG AND SOUTH OF I-70. THE
AIRMASS NORTH OF THE FRONT CONTAINS A HIGH MOISTURE CONTENT, WITH
DEWPOINTS IN THE LOWER 70S ALL THE WAY NORTH TO LACON. DEWPOINT
DEPRESSIONS ARE DOWN TO 1-3F FOR THE TAF SITES. DESPITE THE HIGH
CLOUD COVER, SOME LIGHT MVFR FOG WILL BE POSSIBLE LATER TONIGHT.
WE WENT WITH A PREVAILING MVFR VIS FROM 11-14Z.
SCATTERED SHOWERS ARE INDICATED TO ERUPT LATER TONIGHT IN A WEST
TO EAST LINE ACROSS OUR SOUTHERN COUNTIES, INCLUDING SPI. THE HRRR
SHOWS THOSE SHOWERS/STORMS LIFTING TO THE NORTHEAST OVERNIGHT, BUT
DISSIPATING AS THE REACH TOWARD CMI. WE INCLUDED VCSH FOR ALL BUT
PIA FOR LATE TONIGHT FOR NOW.
A BREAK IN THE PRECIP IS EXPECTED DURING THE DAY TOMORROW, WITH
ALL SITES SEEING STORM CHANCES INCREASE TOMORROW EVENING. WE
INCLUDED VCTS AT ALL TAF SITES AFTER 00Z.
SOUTHWEST WINDS WILL INCREASE TO 15G25KT ACROSS THE BOARD
TOMORROW, AND SUSTAIN IN THE 10-15KT RANGE INTO THE EVENING.
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...SHIMON
SHORT TERM...07
LONG TERM...AUTEN
AVIATION...SHIMON
AREA FORECAST DISCUSSION
NWS NORTHERN INDIANA
112 PM EDT MON JUN 22 2015
.SYNOPSIS...
ISSUED AT 300 AM EDT MON JUN 22 2015
SEVERE STORMS ARE POSSIBLE THIS AFTERNOON TONIGHT...ESPECIALLY
FROM FAR SOUTHERN LOWER MICHIGAN INTO NORTHERN INDIANA AND
NORTHWEST OHIO AS A STRONG UPPER LEVEL SYSTEM TRACKS EASTWARD
THROUGH THE GREAT LAKES. HIGHS TODAY WILL GENERALLY BE IN THE
UPPER 80S. LOWS TONIGHT WILL BE IN THE UPPER 60S TO LOWER 70S.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 406 AM EDT MON JUN 22 2015
A WARM FRONT WAS LIFTING NORTHEAST ALONG WITH THE
LEADING EDGE OF AN ELEVATED MIXED LAYER. SOME STORMS WERE ALREADY
FORMING OVER EAST IA ALONG THIS BOUNDARY. ADDED A MENTION OF THUNDER
THIS MORNING MOST AREAS AS THIS BOUNDARY LIFTS NORTHEAST OVER THE
FORECAST AREA. VERY UNSTABLE CONDITIONS WILL DEVELOP THIS AFTERNOON
SOUTH OF CONVECTION WITH CAPE VALUES APPROACHING 5000 J/KG PER NAM
BUFKIT. NCEP HIGH RES MODELS...ESPECIALLY THE HRRR HAD INITIALIZED
UPSTREAM CONVECTION VERY GOOD AND APPEARED TO BB HANDLING STORM
DEVELOPMENT AND PROPAGATION WELL. MADE SOME FAIRLY SIGNIFICANT
UPDATES IN REGARD TO THE TIMING OF STORMS TODAY AS AN UPSTREAM SHORT
WAVE ARRIVES. COORDINATED SEVERE CHANCES WITH SPC AND SURROUNDING
OFFICES IN REGARD TO THE MENTION OF SEVERE STORMS THIS AFTERNOON AND
TONIGHT. IN ADDITION TO DAMAGING WINDS...HEAVY RAINFALL IS LIKELY.
CONCERN WITH ONGOING FLOODING WITH ADDITIONAL HEAVY RAINFALL. WILL
MENTION HEAVY RAINFALL IN THE HAZARDOUS WEATHER OUTLOOK.
&&
.LONG TERM...(TUESDAY THROUGH SUNDAY)
ISSUED AT 406 AM EDT MON JUN 22 2015
ACTIVE PATTERN TO CONTINUE INTO NEXT WEEKEND...WITH PRIMARY
FORECAST FOCUS ON THE WEDNESDAY NIGHT-THURSDAY TIMEFRAME.
SOME LINGERING SHOWERS AND THUNDERSTORMS ARE POSSIBLE ACROSS THE
EXTREME SOUTHEAST PORTIONS OF THE FORECAST AREA TUESDAY MORNING AS
COLD FRONT SWEEPS ACROSS THE AREA. OTHERWISE...TUESDAY IS STILL
SHAPING UP TO BE A QUIET AND NOTICEABLY LESS HUMID TODAY AS
DRY...COOL LOW LEVEL AIR ADVECTION OVERSPREADS THE AREA. NO
SIGNIFICANT SHORT WAVES APPEAR POISED TO CAUSE IMMEDIATE NORTHWARD
ADVANCE OF LOW LEVEL THETAE BOUNDARY FOR THE TUESDAY-WEDNESDAY
TIMEFRAME AND HAVE MAINTAINED JUST LOW CHANCE POPS RETURNING ACROSS
THE WEST/SOUTHWEST PORTIONS OF THE AREA FOR WEDNESDAY AFTERNOON.
A MORE PRONOUNCED MID LEVEL TROUGH IS EXPECTED TO APPROACH MID MS
RIVER VALLEY LATE WEDNESDAY NIGHT WITH A SHARP RAMP OF S-SW LLJ.
STRONG MOISTURE CONVERGENCE AT THE NOSE OF THIS LOW LEVEL JET AND
INCREASING LARGE SCALE SUPPORT IN BROAD RIGHT ENTRANCE REGION TO 100
KNOT GREAT LAKES UPPER JET STREAK SHOULD SUPPORT SHOWERS AND
THUNDERSTORMS OVERSPREADING THE AREA WEDNESDAY NIGHT INTO THURSDAY
MORNING. CONVECTIVE EVOLUTION MAY TAKE THE SHAPE OF ANOTHER MCS
MOVING THROUGH THE AREA FROM THE MID MS RIVER VALLEY. PROLONGED
STRONG LOW LEVEL MOISTURE CONVERGENCE AND WARM CLOUD DEPTHS
INCREASING TO 12-13K FT SUGGEST HEAVY RAIN POTENTIAL STILL IN ORDER.
SEVERE THREAT SOMEWHAT UNCLEAR DEPENDING ON EXACT ORIENTATION OF
LOW/MID LEVEL THETAE AXIS BUT EARLY INDICATIONS WOULD SUGGEST
PERHAPS SOUTHERN HALF WITH BEST COMBINATION OF SHEAR/INSTABILITY FOR
SEVERE THREAT. BETTER CHANCE OF SEVERE STORMS MAY SHIFT SOUTH OF
LOCAL AREA BY THURSDAY WITH COMPOSITE OUTFLOW BOUNDARY...BUT STILL A
GOOD DEAL OF UNCERTAINTY WITH MESOSCALE FACTORS REGARDING UPSTREAM
EVOLUTION WEDNESDAY/WEDNESDAY NIGHT STILL OF LOW CONFIDENCE.
THREAT OF HEAVIER SHOWERS AND STORMS SHOULD WANE BY FRIDAY AS FRONT
SAGS SOUTH AGAIN. COOLER TEMPS BACK IN THE 70S ARE EXPECTED FOR
REMAINDER OF THE PERIOD ALTHOUGH DID OPT TO KEEP BROAD BRUSH CHANCE
POPS THROUGH NEXT WEEKEND DUE TO PERTURBED NORTHWEST FLOW.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON)
ISSUED AT 110 PM EDT MON JUN 22 2015
LINE OF TS MOVG ACROSS NRN IL WAS WKNG EARLY THIS AFTN AS STORMS
MOVE AWAY FROM STRONGER FORCING... SO WILL LEAVE MENTION OF TS OUT
OF TAFS FOR THIS AFTN WITH MAINLY VFR CONDITIONS EXPECTED. ANOTHER
LINE OF TS IS EXPECTED TO DEVELOP NEAR CDFNT LATE THIS AFTN AND
DROP SE ACROSS NRN INDIANA TONIGHT. PREVIOUS TAFS TIMING/STRENGTH
OF THIS ACTIVITY STILL LOOKS REASONABLE AND NO CHANGES MADE. FROPA
EXPECTED AROUND 09Z AT SBN AND 12Z AT FWA. SOME POTENTIAL FOR
BRIEF LOW MVFR OR IFR CIGS ALONG THE FRONT BUT FOR NOW FAVORED
SOMEWHAT DRIER GFS WITH JUST SCT LOW CLOUDS AROUND THIS TIME. IN
EITHER CASE EXPECT CONDITIONS TO BE VFR AND CIG FREE BY LATE
MORNING WITH MODEST NW WINDS BEHIND THE FRONT.
&&
.IWX WATCHES/WARNINGS/ADVISORIES...
IN...BEACH HAZARDS STATEMENT THROUGH LATE TONIGHT FOR INZ003.
MI...BEACH HAZARDS STATEMENT THROUGH LATE TONIGHT FOR MIZ077.
OH...NONE.
LM...SMALL CRAFT ADVISORY UNTIL MIDNIGHT EDT TONIGHT FOR LMZ043-046.
&&
$$
SYNOPSIS...SKIPPER
SHORT TERM...SKIPPER
LONG TERM...MARSILI
AVIATION...JT
VISIT US AT WWW.WEATHER.GOV/IWX (ALL LOWER CASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
WWW.FACEBOOK.COM/NWSNORTHERNINDIANA
WWW.TWITTER.COM/NWSIWX
WWW.YOUTUBE.COM/NWSNORTHERNINDIANA
AREA FORECAST DISCUSSION
NWS NORTHERN INDIANA
603 AM EDT MON JUN 22 2015
.SYNOPSIS...
ISSUED AT 300 AM EDT MON JUN 22 2015
SEVERE STORMS ARE POSSIBLE THIS AFTERNOON TONIGHT...ESPECIALLY
FROM FAR SOUTHERN LOWER MICHIGAN INTO NORTHERN INDIANA AND
NORTHWEST OHIO AS A STRONG UPPER LEVEL SYSTEM TRACKS EASTWARD
THROUGH THE GREAT LAKES. HIGHS TODAY WILL GENERALLY BE IN THE
UPPER 80S. LOWS TONIGHT WILL BE IN THE UPPER 60S TO LOWER 70S.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 406 AM EDT MON JUN 22 2015
A WARM FRONT WAS LIFTING NORTHEAST ALONG WITH THE
LEADING EDGE OF AN ELEVATED MIXED LAYER. SOME STORMS WERE ALREADY
FORMING OVER EAST IA ALONG THIS BOUNDARY. ADDED A MENTION OF THUNDER
THIS MORNING MOST AREAS AS THIS BOUNDARY LIFTS NORTHEAST OVER THE
FORECAST AREA. VERY UNSTABLE CONDITIONS WILL DEVELOP THIS AFTERNOON
SOUTH OF CONVECTION WITH CAPE VALUES APPROACHING 5000 J/KG PER NAM
BUFKIT. NCEP HIGH RES MODELS...ESPECIALLY THE HRRR HAD INITIALIZED
UPSTREAM CONVECTION VERY GOOD AND APPEARED TO BB HANDLING STORM
DEVELOPMENT AND PROPAGATION WELL. MADE SOME FAIRLY SIGNIFICANT
UPDATES IN REGARD TO THE TIMING OF STORMS TODAY AS AN UPSTREAM SHORT
WAVE ARRIVES. COORDINATED SEVERE CHANCES WITH SPC AND SURROUNDING
OFFICES IN REGARD TO THE MENTION OF SEVERE STORMS THIS AFTERNOON AND
TONIGHT. IN ADDITION TO DAMAGING WINDS...HEAVY RAINFALL IS LIKELY.
CONCERN WITH ONGOING FLOODING WITH ADDITIONAL HEAVY RAINFALL. WILL
MENTION HEAVY RAINFALL IN THE HAZARDOUS WEATHER OUTLOOK.
&&
.LONG TERM...(TUESDAY THROUGH SUNDAY)
ISSUED AT 406 AM EDT MON JUN 22 2015
ACTIVE PATTERN TO CONTINUE INTO NEXT WEEKEND...WITH PRIMARY
FORECAST FOCUS ON THE WEDNESDAY NIGHT-THURSDAY TIMEFRAME.
SOME LINGERING SHOWERS AND THUNDERSTORMS ARE POSSIBLE ACROSS THE
EXTREME SOUTHEAST PORTIONS OF THE FORECAST AREA TUESDAY MORNING AS
COLD FRONT SWEEPS ACROSS THE AREA. OTHERWISE...TUESDAY IS STILL
SHAPING UP TO BE A QUIET AND NOTICEABLY LESS HUMID TODAY AS
DRY...COOL LOW LEVEL AIR ADVECTION OVERSPREADS THE AREA. NO
SIGNIFICANT SHORT WAVES APPEAR POISED TO CAUSE IMMEDIATE NORTHWARD
ADVANCE OF LOW LEVEL THETAE BOUNDARY FOR THE TUESDAY-WEDNESDAY
TIMEFRAME AND HAVE MAINTAINED JUST LOW CHANCE POPS RETURNING ACROSS
THE WEST/SOUTHWEST PORTIONS OF THE AREA FOR WEDNESDAY AFTERNOON.
A MORE PRONOUNCED MID LEVEL TROUGH IS EXPECTED TO APPROACH MID MS
RIVER VALLEY LATE WEDNESDAY NIGHT WITH A SHARP RAMP OF S-SW LLJ.
STRONG MOISTURE CONVERGENCE AT THE NOSE OF THIS LOW LEVEL JET AND
INCREASING LARGE SCALE SUPPORT IN BROAD RIGHT ENTRANCE REGION TO 100
KNOT GREAT LAKES UPPER JET STREAK SHOULD SUPPORT SHOWERS AND
THUNDERSTORMS OVERSPREADING THE AREA WEDNESDAY NIGHT INTO THURSDAY
MORNING. CONVECTIVE EVOLUTION MAY TAKE THE SHAPE OF ANOTHER MCS
MOVING THROUGH THE AREA FROM THE MID MS RIVER VALLEY. PROLONGED
STRONG LOW LEVEL MOISTURE CONVERGENCE AND WARM CLOUD DEPTHS
INCREASING TO 12-13K FT SUGGEST HEAVY RAIN POTENTIAL STILL IN ORDER.
SEVERE THREAT SOMEWHAT UNCLEAR DEPENDING ON EXACT ORIENTATION OF
LOW/MID LEVEL THETAE AXIS BUT EARLY INDICATIONS WOULD SUGGEST
PERHAPS SOUTHERN HALF WITH BEST COMBINATION OF SHEAR/INSTABILITY FOR
SEVERE THREAT. BETTER CHANCE OF SEVERE STORMS MAY SHIFT SOUTH OF
LOCAL AREA BY THURSDAY WITH COMPOSITE OUTFLOW BOUNDARY...BUT STILL A
GOOD DEAL OF UNCERTAINTY WITH MESOSCALE FACTORS REGARDING UPSTREAM
EVOLUTION WEDNESDAY/WEDNESDAY NIGHT STILL OF LOW CONFIDENCE.
THREAT OF HEAVIER SHOWERS AND STORMS SHOULD WANE BY FRIDAY AS FRONT
SAGS SOUTH AGAIN. COOLER TEMPS BACK IN THE 70S ARE EXPECTED FOR
REMAINDER OF THE PERIOD ALTHOUGH DID OPT TO KEEP BROAD BRUSH CHANCE
POPS THROUGH NEXT WEEKEND DUE TO PERTURBED NORTHWEST FLOW.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z TUESDAY MORNING)
ISSUED AT 600 AM EDT MON JUN 22 2015
A WARM FRONT WAS LIFTING NORTHEAST ALONG WITH THE LEADING EDGE OF
AN ELEVATED MIXED LAYER. SOME STORMS WERE ALREADY FORMING OVER
EAST IA ALONG THIS BOUNDARY. ADJUSTED SLIGHTLY A MENTION OF
THUNDER AT SBN FROM 15Z TO 19Z AS THIS BOUNDARY LIFTS NORTHEAST.
VERY UNSTABLE CONDITIONS WILL DEVELOP LATE THIS AFTERNOON SOUTH OF
CONVECTION WITH CAPE VALUES APPROACHING 5000 J/KG PER NAM BUFKIT.
THE BEST CHANCE FOR THUNDER TONIGHT SHOULD BE AROUND OR AFTER
03Z...SO PLACED TIMING OF STORMS IN TAFS TONIGHT.
&&
.IWX WATCHES/WARNINGS/ADVISORIES...
IN...BEACH HAZARDS STATEMENT FROM 1 PM CDT THIS AFTERNOON THROUGH
LATE TONIGHT FOR INZ003.
MI...BEACH HAZARDS STATEMENT FROM 2 PM EDT THIS AFTERNOON THROUGH
LATE TONIGHT FOR MIZ077.
OH...NONE.
LM...SMALL CRAFT ADVISORY FROM 2 PM THIS AFTERNOON TO MIDNIGHT EDT
TONIGHT FOR LMZ043-046.
&&
$$
SYNOPSIS...SKIPPER
SHORT TERM...SKIPPER
LONG TERM...MARSILI
AVIATION...SKIPPER
VISIT US AT WWW.WEATHER.GOV/IWX (ALL LOWER CASE)
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AREA FORECAST DISCUSSION
NWS NORTHERN INDIANA
407 AM EDT MON JUN 22 2015
.SYNOPSIS...
ISSUED AT 300 AM EDT MON JUN 22 2015
SEVERE STORMS ARE POSSIBLE THIS AFTERNOON TONIGHT...ESPECIALLY
FROM FAR SOUTHERN LOWER MICHIGAN INTO NORTHERN INDIANA AND
NORTHWEST OHIO AS A STRONG UPPER LEVEL SYSTEM TRACKS EASTWARD
THROUGH THE GREAT LAKES. HIGHS TODAY WILL GENERALLY BE IN THE
UPPER 80S. LOWS TONIGHT WILL BE IN THE UPPER 60S TO LOWER 70S.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 406 AM EDT MON JUN 22 2015
A WARM FRONT WAS LIFTING NORTHEAST ALONG WITH THE
LEADING EDGE OF AN ELEVATED MIXED LAYER. SOME STORMS WERE ALREADY
FORMING OVER EAST IA ALONG THIS BOUNDARY. ADDED A MENTION OF THUNDER
THIS MORNING MOST AREAS AS THIS BOUNDARY LIFTS NORTHEAST OVER THE
FORECAST AREA. VERY UNSTABLE CONDITIONS WILL DEVELOP THIS AFTERNOON
SOUTH OF CONVECTION WITH CAPE VALUES APPROACHING 5000 J/KG PER NAM
BUFKIT. NCEP HIGH RES MODELS...ESPECIALLY THE HRRR HAD INITIALIZED
UPSTREAM CONVECTION VERY GOOD AND APPEARED TO BB HANDLING STORM
DEVELOPMENT AND PROPAGATION WELL. MADE SOME FAIRLY SIGNIFICANT
UPDATES IN REGARD TO THE TIMING OF STORMS TODAY AS AN UPSTREAM SHORT
WAVE ARRIVES. COORDINATED SEVERE CHANCES WITH SPC AND SURROUNDING
OFFICES IN REGARD TO THE MENTION OF SEVERE STORMS THIS AFTERNOON AND
TONIGHT. IN ADDITION TO DAMAGING WINDS...HEAVY RAINFALL IS LIKELY.
CONCERN WITH ONGOING FLOODING WITH ADDITIONAL HEAVY RAINFALL. WILL
MENTION HEAVY RAINFALL IN THE HAZARDOUS WEATHER OUTLOOK.
&&
.LONG TERM...(TUESDAY THROUGH SUNDAY)
ISSUED AT 406 AM EDT MON JUN 22 2015
ACTIVE PATTERN TO CONTINUE INTO NEXT WEEKEND...WITH PRIMARY
FORECAST FOCUS ON THE WEDNESDAY NIGHT-THURSDAY TIMEFRAME.
SOME LINGERING SHOWERS AND THUNDERSTORMS ARE POSSIBLE ACROSS THE
EXTREME SOUTHEAST PORTIONS OF THE FORECAST AREA TUESDAY MORNING AS
COLD FRONT SWEEPS ACROSS THE AREA. OTHERWISE...TUESDAY IS STILL
SHAPING UP TO BE A QUIET AND NOTICEABLY LESS HUMID TODAY AS
DRY...COOL LOW LEVEL AIR ADVECTION OVERSPREADS THE AREA. NO
SIGNIFICANT SHORT WAVES APPEAR POISED TO CAUSE IMMEDIATE NORTHWARD
ADVANCE OF LOW LEVEL THETAE BOUNDARY FOR THE TUESDAY-WEDNESDAY
TIMEFRAME AND HAVE MAINTAINED JUST LOW CHANCE POPS RETURNING ACROSS
THE WEST/SOUTHWEST PORTIONS OF THE AREA FOR WEDNESDAY AFTERNOON.
A MORE PRONOUNCED MID LEVEL TROUGH IS EXPECTED TO APPROACH MID MS
RIVER VALLEY LATE WEDNESDAY NIGHT WITH A SHARP RAMP OF S-SW LLJ.
STRONG MOISTURE CONVERGENCE AT THE NOSE OF THIS LOW LEVEL JET AND
INCREASING LARGE SCALE SUPPORT IN BROAD RIGHT ENTRANCE REGION TO 100
KNOT GREAT LAKES UPPER JET STREAK SHOULD SUPPORT SHOWERS AND
THUNDERSTORMS OVERSPREADING THE AREA WEDNESDAY NIGHT INTO THURSDAY
MORNING. CONVECTIVE EVOLUTION MAY TAKE THE SHAPE OF ANOTHER MCS
MOVING THROUGH THE AREA FROM THE MID MS RIVER VALLEY. PROLONGED
STRONG LOW LEVEL MOISTURE CONVERGENCE AND WARM CLOUD DEPTHS
INCREASING TO 12-13K FT SUGGEST HEAVY RAIN POTENTIAL STILL IN ORDER.
SEVERE THREAT SOMEWHAT UNCLEAR DEPENDING ON EXACT ORIENTATION OF
LOW/MID LEVEL THETAE AXIS BUT EARLY INDICATIONS WOULD SUGGEST
PERHAPS SOUTHERN HALF WITH BEST COMBINATION OF SHEAR/INSTABILITY FOR
SEVERE THREAT. BETTER CHANCE OF SEVERE STORMS MAY SHIFT SOUTH OF
LOCAL AREA BY THURSDAY WITH COMPOSITE OUTFLOW BOUNDARY...BUT STILL A
GOOD DEAL OF UNCERTAINTY WITH MESOSCALE FACTORS REGARDING UPSTREAM
EVOLUTION WEDNESDAY/WEDNESDAY NIGHT STILL OF LOW CONFIDENCE.
THREAT OF HEAVIER SHOWERS AND STORMS SHOULD WANE BY FRIDAY AS FRONT
SAGS SOUTH AGAIN. COOLER TEMPS BACK IN THE 70S ARE EXPECTED FOR
REMAINDER OF THE PERIOD ALTHOUGH DID OPT TO KEEP BROAD BRUSH CHANCE
POPS THROUGH NEXT WEEKEND DUE TO PERTURBED NORTHWEST FLOW.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT)
ISSUED AT 300 AM EDT MON JUN 22 2015
A WARM FRONT WAS LIFTING NORTHEAST ALONG WITH THE LEADING EDGE OF
AN ELEVATED MIXED LAYER. SOME STORMS WERE ALREADY FORMING OVER
EAST IA ALONG THIS BOUNDARY. ADDED A MENTION OF THUNDER AT SBN
FROM 16Z TO 19Z AS THIS BOUNDARY LIFTS NORTHEAST. VERY UNSTABLE
CONDITIONS WILL DEVELOP LATE THIS AFTERNOON SOUTH OF CONVECTION
WITH CAPE VALUES APPROACHING 5000 J/KG PER NAM BUFKIT. THE BEST
CHANCE FOR THUNDER TONIGHT SHOULD BE AROUND OR AFTER 06Z...SO
KEPT THUNDER OUT EARLY TONIGHT...BUT WILL BE MENTIONING THUNDER
TONIGHT ON THE 12Z TAF ISSUANCE. CONDITIONS INDICATE STORMS COULD
BECOME SEVERE WITH WIND GUSTS 50 KTS OR HIGHER ESPECIALLY AT SBN
AT SOME POINT TONIGHT.
&&
.IWX WATCHES/WARNINGS/ADVISORIES...
IN...BEACH HAZARDS STATEMENT FROM 1 PM CDT THIS AFTERNOON THROUGH
LATE TONIGHT FOR INZ003.
MI...BEACH HAZARDS STATEMENT FROM 2 PM EDT THIS AFTERNOON THROUGH
LATE TONIGHT FOR MIZ077.
OH...NONE.
LM...SMALL CRAFT ADVISORY FROM 2 PM THIS AFTERNOON TO MIDNIGHT EDT
TONIGHT FOR LMZ043-046.
&&
$$
SYNOPSIS...SKIPPER
SHORT TERM...SKIPPER
LONG TERM...MARSILI
AVIATION...SKIPPER
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WWW.TWITTER.COM/NWSIWX
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AREA FORECAST DISCUSSION
NWS QUAD CITIES IA IL
356 PM CDT MON JUN 22 2015
.SYNOPSIS...
ISSUED AT 355 PM CDT MON JUN 22 2015
BOW ECHO THAT PRODUCED 70 TO 90 MPH DESTRUCTIVE WINDS ACROSS OUR
FAR NORTHERN COUNTIES THIS MORNING HAS LEFT A RAIN COOLED BOUNDARY
NORTH OF I-80. STRONG MOISTURE TRANSPORT AND STRONG SHEAR HAD DEVELOPED
AN ISOLATED ELEVATED SEVERE THUNDERSTORM EARLY THIS AFTERNOON IN
THE CEDAR RAPIDS AREA...WITH HAIL UP TO BASEBALL SIZE. ISOLATED
ELEVATED THUNDERSTORMS WITH MAINLY VERY LARGE HAIL WILL CONTINUE
TO FESTER THROUGH THE AFTERNOON. WITH THE CLOUD COVER I HAVE
LOWERED TEMPERATURES AND DEWPOINTS SEVERAL DEGREES.
LATER THIS AFTERNOON THROUGH THE EVENING...STRONG COLD FRONT IN NW
IA WILL BE PUSHING INTO OUR FAR NW CWA BY EVENING. DEWPOINTS WERE
IN THE 40S WITH GUSTY NW WINDS BEHIND THE FRONT. CAPES WILL BUILD
AS THE AFTERNOON PROGRESSES WITH STORMS BECOMING SURFACE BASED.
THE HRRR DEVELOPS DISCRETE SUPERCELLS NEAR HIGHWAY 30 BY MID TO
LATE AFTERNOON THEN PROGRESSING SOUTHEAST AND FORMING INTO ANOTHER
BOW ECHO. THESE STORMS WILL PRODUCE VERY LARGE HAIL AND A FEW TORNADOES
TRANSITIONING TO WIDESPREAD DAMAGING WINDS OF 70+ MPH AS IT PUSHES
INTO OUR SOUTHERN AND EASTERN COUNTIES. TO SAY THE LEAST THIS IS
ANOTHER DANGEROUS SEVERE WEATHER SITUATION UNFOLDING. THE SEVERE
THREAT WILL END WITH THE PASSAGE OF THE FRONT AND SHOULD BE PRETTY
MUCH OVER WITH IN THE DVN CWA BY MIDNIGHT.
3 PM TEMPERATURES RANGED FROM THE LOWER 70S IN RAIN AREAS IN OUR
NORTH TO THE MID 80S SOUTH. DEWPOINTS WERE IN THE 70S. SPC MESO
ANALYSIS INDICATED SBCAPES OF 6000 J/KG IN NW MO WITH A TIGHT
GRADIENT OVER EASTERN IA (BEWARE OF THE GRADIENT). EFFECTIVE BULK
SHEAR WAS 70 KNOTS...HELICITY 300 M2/S2 WITH 1 KM EHI OF 5. STRONG
850 MB MOISTURE TRANSPORT WAS EVIDENT ALONG WITH PWAT`S OF NEARLY
2 INCHES.
&&
.SHORT TERM...(THIS EVENING THROUGH TUESDAY)
ISSUED AT 355 PM CDT MON JUN 22 2015
FORECAST FOCUS ON SEVERE WEATHER THIS EVENING THEN BRIEFLY QUIET
ON TUESDAY.
TONIGHT...MOST OF THE DETAILS WERE NOTED IN THE SYNOPSIS SECTION
ABOVE BUT THE MAIN MESSAGE WILL BE THE SEVERE WEATHER THREAT WILL
END BY 10 OR 11 PM. THIS IS DUE TO A COLD FRONT MOVING ACROSS THE
CWA AS WINDS TURN NORTHWEST...USHERING COOLER AND LESS HUMID AIR
INTO THE AREA. MINIMUM TEMPERATURES WILL RANGE AROUND 60 ALONG
HIGHWAY 20 TO THE UPPER 60S FAR SOUTH.
TUESDAY...WEAK HIGH PRESSURE WILL PROVIDE A RATHER PLEASANT DAY
WITH COMFORTABLE HUMIDITY AND COOLER TEMPERATURES...WITH NORTH
WINDS AROUND 10 MPH. DEWPOINTS SHOULD BE IN THE 50S WITH AFTERNOON
HIGH TEMPERATURES IN THE UPPER 70S TO LOWER 80S.
.LONG TERM...(TUESDAY NIGHT THROUGH MONDAY)
ISSUED AT 355 PM CDT MON JUN 22 2015
FORECAST FOCUS ON THUNDERSTORMS RETURNING TUESDAY NIGHT THROUGH
MOST OF THE REMAINDER OF THE WEEK...THEN COOLER BY THE WEEKEND.
TUESDAY NIGHT THROUGH FRIDAY...FRONTAL BOUNDARY RETURNS AS A WARM
FRONT TUESDAY NIGHT WITH A CHANCE OF STORMS IN OUR FAR SOUTH. ON
WEDNESDAY THE FRONT LOOKS TO STALL OVER THE DVN WITH THE POTENTIAL
FOR HEAVY RAINFALL AND SEVERE WEATHER AGAIN. SPC HAS THE ENTIRE
CWA IN A SLIGHT RISK. DEWPOINTS WILL BE RISING WELL INTO THE 60S
TO LOWER 70S WITH AFTERNOON MAXIMUM TEMPERATURES IN THE UPPER 70S
NORTH TO UPPER 80S SOUTH. THE ECMWF SUGGESTS THE FRONT TO DROP
SOUTHWARD LATE IN THE WEEK WITH ONLY OUR FAR SOUTH STILL HAVING A
CHANCE OF STORMS. THE GFS HAS THE FRONT WELL TO OUR SOUTH WITH DRY
WEATHER BY FRIDAY.
THIS WEEKEND...NORTHWEST TO NORTH FLOW ALOFT WITH COMFORTABLE
TEMPERATURES AND HUMIDITY AND MAINLY DRY. HIGHS WILL BE IN THE 70S
TO NEAR 80 WITH LOWS AROUND 60.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON)
ISSUED AT 125 PM CDT MON JUN 22 2015
VFR CONDS THROUGH THIS TAF CYCLE EXCEPT MVFR/IFR CONDS IN
THUNDERSTORMS. DISCRETE SUPERCELLS THIS AFTERNOON AND EARLY
EVENING WILL UPSCALE INTO A BOW ECHO AS IT PUSHES SOUTHEAST ACROSS
THE TAF SITES. VERY LARGE HAIL...DAMAGING WINDS OF 70+ MPH AND A
FEW TORNADOES ARE ALL LIKELY THROUGH THIS EVENING. SOUTH TO
SOUTHWEST WINDS 10 TO 20 KNOTS AHEAD OF THE FRONT THEN NORTHWEST
TO NORTH BEHIND THE FRONT TONIGHT AND TUESDAY.
&&
.DVN WATCHES/WARNINGS/ADVISORIES...
IA...NONE.
IL...NONE.
MO...NONE.
&&
$$
SYNOPSIS...HAASE
SHORT TERM...HAASE
LONG TERM...HAASE
AVIATION...HAASE
AREA FORECAST DISCUSSION
NWS QUAD CITIES IA IL
124 PM CDT MON JUN 22 2015
.UPDATE...
ISSUED AT 125 PM CDT MON JUN 22 2015
BOW ECHO THAT PRODUCED 70 TO 90 MPH DESTRUCTIVE WINDS ACROSS OUR
FAR NORTHERN COUNTIES THIS MORNING HAS LEFT A RAIN COOLED BOUNDARY
NORTH OF I-80. STRONG MOISTURE TRANSPORT AND STRONG SHEAR HAS
DEVELOPED AN ISOLATED ELEVATED SEVERE THUNDERSTORM IN THE CEDAR
RAPIDS AREA...WITH HAIL UP TO HEN EGG SIZE. ISOLATED ELEVATED
THUNDERSTORMS WITH MAINLY VERY LARGE HAIL WILL CONTINUE TO FESTER
THROUGH THE AFTERNOON. WITH THE CLOUD COVER I HAVE LOWERED TEMPERATURES
AND DEWPOINTS SEVERAL DEGREES.
LATER THIS AFTERNOON THROUGH THE EVENING...STRONG COLD FRONT IN NW
IA WILL BE PUSHING INTO OUR FAR NW CWA BY EVENING. DEWPOINTS WERE
IN THE 40S WITH GUSTY NW WINDS BEHIND THE FRONT. CAPES WILL BUILD
AS THE AFTERNOON PROGRESSES WITH STORMS BECOMING SURFACE BASED.
THE HRRR DEVELOPS DISCRETE SUPERCELLS IN OUR NW CWA BY MID TO LATE
AFTERNOON THEN PROGRESSING SOUTHEAST AND FORMING INTO ANOTHER BOW
ECHO. THESE STORMS WILL PRODUCE VERY LARGE HAIL AND A FEW TORNADOES
TRANSITIONING TO WIDESPREAD DAMAGING WINDS OF 70+ MPH AS IT PUSHES
INTO OUR SOUTHERN AND EASTERN COUNTIES. TO SAY THE LEAST THIS IS
ANOTHER DANGEROUS SEVERE WEATHER SITUATION UNFOLDING. THE SEVERE
THREAT WILL END WITH THE PASSAGE OF THE FRONT AND SHOULD BE PRETTY
MUCH OVER WITH IN THE DVN CWA BY MIDNIGHT.
UPDATE ISSUED AT 635 AM CDT MON JUN 22 2015
FEW UPDATES TO FORECAST. HAVE INCREASED POPS SLIGHTLY AS NORTHERN
CWA MAY GET A GLANCING PASS BY THE SEVERE MCS TO OUR NORTH. THINK
THAT THE STORMS WILL BE WEAKENING. AN ISOLATED 50 MPH GUST AND
EVEN A SEVERE GUST CANNOT BE RULED OUT. WAA AS ADVANCED THROUGH
THE CWA.
&&
.SYNOPSIS...
ISSUED AT 330 AM CDT MON JUN 22 2015
WARM ADVECTION WING IN FULL MOTION THIS MORNING AS MOISTURE SURGES
NORTH IN RESPONSE TO A LOW PRESSURE SYSTEM DEEPENING AND MOVING
TO THE NORTH OF THE AREA. A RATHER STICKY NIGHT FOR US AS SOME
LIGHT SHOWERS HAVE DEVELOPED ON THIS WING OF WAA. SOME
THUNDERSTORMS HAVE ALSO FORMED ACROSS FAR NW ZONES THIS MORNING AS
THE WARM FRONT MOVES TO THE NORTH. THIS WARM FRONT IS EXPECTED TO
CONTINUE SURGING NORTH. CURRENT PRESSURE FALLS SUPPORT THE NOTION
OF THIS AS WELL. THIS WILL KEEP THE SEVERE MCS TO OUR NORTH THIS
MORNING.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 330 AM CDT MON JUN 22 2015
MAIN FORECAST CONCERN FOR THE SHORT TERM FORECAST ARE THE CHANCES
FOR STRONG TO SEVERE WEATHER TODAY ACROSS THE AREA. CONCERNS
REMAIN ABOUT CONVECTION THIS MORNING AND OVERALL COVERAGE ONCE
STORMS INITIATE THIS AFTERNOON.
CONVECTION ONGOING ACROSS SOUTH DAKOTA WILL LIKELY STAY NORTH OR
JUST CLIP FAR NORTHERN ZONES OF THE CWA TODAY. THIS MEANS THAT
CLOUD COVER WILL BE ACROSS THE AREA ALONG WITH SOME OFBS. THESE
OFBS AND DIFFERENTIAL HEATING BOUNDARIES WILL SERVE AS POTENTIAL
INITIATION POINTS BEFORE THE COLD FRONT COMES THROUGH THE AREA.
THESE SPECIFICS WILL BECOME CLEARER AFTER THE MORNINGS CONVECTION
MOVES THROUGH THE AREA.
VERY WARM AND MOIST AIRMASS IS IN PLACE AND WILL STAY IN PLACE
THROUGH THE DAY TODAY. STRONG H7 CAPPING IS IN PLACE FROM THE SW TO THE NE. ALL MODELS
SUGGEST THAT THE FRONTAL CIRCULATION WILL BREAK THIS CAP AS IT
APPROACHES. WITH THE WARM AND MOIST AIRMASS ACROSS US...EXPECT
VERY LARGE CAPE...AOA 4000 J/KG...BELIEVE THAT THE NAM IS
OVERDOING THE VALUES. REGARDLESS ONCE THIS CAP BREAKS THUNDERSTORM
DEVELOPMENT WILL BE FAST. INITIAL STORM MODE WILL BE SUPERCELLS
CAPABLE OF VERY LARGE HAIL....DAMAGING WINDS AND ISOLATED
TORNADOES...ESPECIALLY CLOSE TO WI WHERE PROXIMITY TO OFBS AND THE
WARM FRONT COULD INCREASE LOW LEVEL HODOGRAPHS. THESE STORMS WILL
LIKELY GROW INTO BOWING SEGMENTS WITH STRONG DAMAGING WINDS BEING
THE MAIN THREATS.
MY CURRENT THINKING IS THIS...WE WILL WATCH A CU FIELD PERCOLATE
THROUGH MOST OF THE AFTERNOON. THE CAP WILL BE BROKEN AROUND 00Z
AND EXPLOSIVE DEVELOPMENT OF SUPERCELLS WILL OCCUR AROUND THE COLD
FRONT. I THINK THAT THE CELLS WILL BE ISOLATED AT FIRST AND MAY
PERSIST THAT WAY FOR A COUPLE OF HOURS. WITH THE 0-6 KM SHEAR
VECTOR NOWHERE NEAR PERPENDICULAR TO THE BOUNDARY...STORMS WILL
QUICKLY GROW UPSCALE ONCE COVERAGE INCREASES.
PWATS ARE EXCEPTIONALLY HIGH. HEAVY RAINS ARE ALSO POSSIBLE...I
THINK ANY FLOODING WOULD BE TIED DIRECTLY TO TRAINING STORMS. I
DONT SEE THIS AS MUCH OF A THREAT AS STORMS WILL LIKELY BE GROWING
UPSCALE INTO AN MCS JUST OUT OR JUST NEAR OUR BORDERS TO THE SOUTH
AND EAST.
TODAY IS A DAY TO PAY ATTENTION TO THE WEATHER AND HAVE A PLAN
IN CASE SEVERE WEATHER DEVELOPS.
ONCE THE FRONT MOVES THROUGH...HIGH PRESSURE AND MUCH COOLER DRIER
AIR MOVES INTO THE AREA.
.LONG TERM...(TUESDAY THROUGH SUNDAY)
ISSUED AT 330 AM CDT MON JUN 22 2015
SIGNIFICANT RAINS MID WEEK AND GENERALLY BELOW NORMAL TEMPERATURES.
LONG TERM FORECAST CONFIDENCE ASSESSMENT...FAIR TO POOR OR AVERAGE
TO BELOW AVERAGE. MAIN ISSUE IS AGAIN PRECIPITATION EVENT LATE
TUESDAY NIGHT THROUGH WEDNESDAY NIGHT. AMERICAN SOLUTIONS TOO FAR
NORTH WITH WARM AIR AND PRECIPITATION. FAST W-NW UPPER FLOW AND
HIGH MOISTURE LEVELS WILL SPAWN LOTS OF CONVECTION WHICH SHOULD KEEP
AREA CLOUDY AND COOLER THIS PERIOD WITH STALLED FRONT TO THE SOUTH
LIKE THE HI-RES ECMWF. LOCAL HEAVY RAIN TECHNIQUES AND UPPER FORCING
ALSO SHOW BEST PLACEMENT OF HEAVY RAINS SHOULD BE ALL OR OVER MOSTLY
THE SOUTHERN HALF OF THE AREA.
OVERVIEW...INITIALIZATION AND VERIFICATION ONCE AGAIN ARE TOO HIGH
ON BL MOISTURE (DEWPOINTS) AND RESULTING IN TOO COPIOUS QPF FIELDS
TO ACTUAL. FAVORED PATTERN ALSO FOR COOL POOLS...OR OUTFLOW
BOUNDARIES WHICH ARE NON-HYDROSTATIC AND NOT ABLE TO BE CAPTURED BY
SOLUTIONS. PREFER A 75/25 MIX OF HI-RES ECMWF TO GFS THROUGH DAY 3
AND THEN WITH NW FLOW A 50/50 BLEND WITH MOSTLY DRY AND BELOW NORMAL
TEMPERATURES.
TUESDAY AND TUESDAY NIGHT...TRENDS CONTINUE FOR A SLIGHTLY STRONGER
AND COOLER WEAK HIGH PRESSURE SYSTEM. HAVE LOWERED TEMPERATURES A
DEGREE OR TOO AND ALSO DEWPOINTS 2 TO 3 DEGREES AS DISCUSSED LAST
NIGHT COULD BE THE CASE AND THIS IS ON TRACK. LATER SHIFTS MAY NEED
TO TRIM A DEGREE OR TWO MORE...ESPECIALLY FOR DEWPOINTS NORTHERN
SECTIONS MAKING FOR ANOTHER NICE AND COMFORTABLE SUMMER DAY.
TUESDAY NIGHT...EXPECT A CONVECTIVE COMPLEX NEAR NE/KS BORDER THAT
WILL LIKELY MOVE EAST INTO FAR SW SECTIONS BY MORNING. LOTS OF
CLOUDS EXPECTED OVER MOST TO ALL THE REGION BY DAYBREAK. RATE OF
CLOUDINESS INCREASING OVERNIGHT WILL IMPACT MINS.
IF CLOUDS DELAYED THEN NE 1/3 OR MORE OF AREA MINS MAY NEED TRIMMING
BY AT LEAST A CATEGORY OR 3 DEGREES...INTO THE UPPER 50S. FAR SW
SECTIONS COULD SEE .5 TO 1 INCH AMOUNTS BY MORNING WITH COMPLEX WITH
A LOW POSSIBILITY OF SEVERE SINCE FRONT SHOULD BE TOO OUR
SOUTH...LIMITING INSTABILITY.
WEDNESDAY AND WEDNESDAY NIGHT...LITTLE CHANGE WITH LOTS OF CLOUDS
AND PRECIPITATION. HEAVIEST PRECIPITATION STILL SLATED BE ROUGHLY
ALONG OR SOUTH OF HIGHWAY 34. FORCING AND MOISTURE PROFILES FAVOR
WIDESPREAD .5 TO 1.5+ AMOUNTS ALONG AND SOUTH OF HIGHWAY 30 WITH
LOCALLY 2 TO 3+ POSSIBLE SOUTH OF HIGHWAY 34. COMBINED WITH TUESDAY
NIGHT EVENT LIKELY WOULD RESULT IN RENEWED HYDRO ISSUES. SEVERE RISK
CONTINUES TO APPEAR WILL BE PROBABLY SOUTH OF IA/MO BORDER. HIGH
TEMPERATURES HAVE LOWERED AS MENTIONED LAST NIGHT AND BASED ON THIS
PATTERN LIKELY NEED LOWERING ANOTHER 5 TO 8+ DEGREES ALONG AND NORTH
OF HIGHWAY 34 DUE TO GOOD EVAPORATIVE COOLING. LOTS OF MID TO UPPER
70S FOR HIGHS APPEAR VERY POSSIBLE...IF NOT PROBABLE FOR LATER
SHIFTS.
FOR THE 24+ HOUR PERIOD...SEE LOCALLY 2 TO 3 INCH AMOUNTS LIKELY FOR
SOME AREAS...THIS SHOULD PUSH SOME AREA RIVERS ONCE AGAIN NEAR TO
OVER BANKFULL WITH SOME RENEWED FLOODING. LOWER END FLASH FLOODING
ALSO MAY OCCUR WITH AMOUNTS OVER 2 INCHES IF FALLS FAST ENOUGH...AS
IN A FEW HOURS OR LESS.
THURSDAY THROUGH SUNDAY...INCREASINGLY STRONGER NW UPPER LEVEL FLOW
TO RESULT IN COOLER AND DRIER WEATHER WITH LITTLE OR NO SIGNIFICANT
ADDITIONAL RAINFALL. TEMPERATURES MOSTLY 3 TO 8 DEGREES BELOW NORMAL
WITH HIGHS MID 70S TO LOWER 80S MOST DAYS AND MINS MID 50S TO LOWER
60S.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON)
ISSUED AT 125 PM CDT MON JUN 22 2015
VFR CONDS THROUGH THIS TAF CYCLE EXCEPT MVFR/IFR CONDS IN
THUNDERSTORMS. DISCRETE SUPERCELLS THIS AFTERNOON AND EARLY
EVENING WILL UPSCALE INTO A BOW ECHO AS IT PUSHES SOUTHEAST ACROSS
THE TAF SITES. VERY LARGE HAIL...DAMAGING WINDS OF 70+ MPH AND A
FEW TORNADOES ARE ALL LIKELY THROUGH THIS EVENING. SOUTH TO
SOUTHWEST WINDS 10 TO 20 KNOTS AHEAD OF THE FRONT THEN NORTHWEST
TO NORTH BEHIND THE FRONT TONIGHT AND TUESDAY.
&&
.DVN WATCHES/WARNINGS/ADVISORIES...
IA...NONE.
IL...NONE.
MO...NONE.
&&
$$
UPDATE...HAASE
SYNOPSIS...GIBBS
SHORT TERM...GIBBS
LONG TERM...NICHOLS
AVIATION...HAASE
AREA FORECAST DISCUSSION
NWS GOODLAND KS
525 PM MDT TUE JUN 23 2015
.SHORT TERM...(THIS AFTERNOON THROUGH WEDNESDAY)
ISSUED AT 154 PM MDT TUE JUN 23 2015
EARLY AFTERNOON WV IMAGERY AND RAP H5 ANALYSIS SHOWS RIDGE STILL IN
PLACE ACROSS SOUTHERN PLAINS WITH WESTERLY ZONAL FLOW ACROSS THE
NORTHERN PLAINS. WEAK SHORTWAVE TROUGHS AND MONSOONAL/PACIFIC FLOW
CONTINUE TO ROTATE ALONG THE WESTERN PERIPHERY OF THE RIDGE AND
INTO THE CENTRAL ROCKIES. AT THE SURFACE STATIONARY FRONT HAS
LIFTED TO NEAR SCOTT CITY JUST SOUTH OF OUR CWA WITH STATIONARY
FRONT ALONG FRONT RANGE.
THIS AFTERNOON-TONIGHT...GUIDANCE CONTINUES TO SHOW WARM FRONT
LIFTING NORTH THROUGH THE AFTERNOON AND EVENING AS LEE TROUGH
DEEPENS. THUNDERSTORMS HAVE ALREADY DEVELOPED ACROSS SOUTH CENTRAL
COLORADO. HIGH RES GUIDANCE CONTINUES TO SHOW CAP WEAKENING
ALONG THE FRONT FROM THE WEST TO THE EAST...AND THUNDERSTORMS
EITHER DEVELOPING OR MOVING INTO THE SW PART OF THE CWA SPREADING
NORTH AND EAST THIS EVENING. WHILE PWATS AND TD VALUES ARE
IMPRESSIVE...DEEP LAYER MIXING RATIOS/MOISTURE PROFILES ARE LESS
THAN FAVORABLE FOR WIDESPREAD COVERAGE LOCALLY WITHOUT
ORGANIZATION INTO MORE OF A CLUSTER FROM THE WEST. SHORTWAVE
TROUGH ADVERTISED TO MOVE ACROSS CWA THIS EVENING COULD HELP WITH
INITIATION...SO DESPITE THE DRY LAYERS ALOFT 20 TO 30 POPS STILL
SEEMS REASONABLE. VEERING SHEER PROFILES IN THE 0-3KM LAYER COULD
HELP SUPERCELL POTENTIAL ASSUMING THUNDERSTORMS DEVELOP THIS
AFTERNOON/EARLY EVENING ALONG WARM FRONT BEFORE LOW LEVELS
STABILIZE. AS EVENING PROGRESSES PROFILES FAVOR MAINLY ELEVATED
THUNDERSTORMS...AND GOOD EFFECTIVE SHEER VALUES SHOULD STILL
SUPPORT LARGE HAIL/DAMAGING WIND THREAT WITH ANY ONGOING ACTIVITY.
WEDNESDAY...WARM FRONT STALLS NEAR THE KS/NE BORDER EARLY WEDNESDAY
MORNING WITH MOISTURE POOLING NORTH OF THIS FRONT EARLY WEDNESDAY
MORNING WHEN FOG/STRATUS COULD DEVELOP. GUIDANCE STILL SHOWING A
POTENTIAL BUT I AM STILL NOT SURE VIS WILL BE LOW ENOUGH TO INCLUDE
MENTION IN FORECAST...SO WILL MONITOR SHORT RANGE
GUIDANCE/TRENDS. FRONT SETS UP ROUGHLY THROUGH THE CENTRAL PART OF
THE CWA AS SURFACE LOW SHIFTS EAST WEDNESDAY AFTERNOON...WITH NEAR
100F TEMPS SOUTH OF THIS FRONT AND IN THE 90S TO THE NW. THIS
FRONT WILL ACT AS A FOCUS FOR POSSIBLY THUNDERSTORM DEVELOPMENT IN
THE AFTERNOON...AGAIN AIDED BY HEIGHT FALLS FROM WEAK SHORTWAVE
ROTATING INTO THE REGION FROM THE WEST. I KEPT 20 POPS CONFINED TO
THE SW IN THE AFTERNOON...THOUGH DEPENDING ON CAP STRENGTH I COULD
SEE A ISOLATED THUNDERSTORM FURTHER EAST. NOT A STRONG SIGNAL IN
THE AFTERNOON FURTHER EAST..SO I FAVOR STICKING WITH A
CONSERVATIVE APPROACH FOR NOW.
.LONG TERM...(WEDNESDAY NIGHT THROUGH TUESDAY)
ISSUED AT 318 PM MDT TUE JUN 23 2015
FORECAST PROBLEMS WILL BE CHANCES OF THUNDERSTORMS THROUGH FRIDAY.
SATELLITE SHOWING A PROGRESSIVE/NEAR ZONAL FLOW FROM THE PACIFIC
INTO THE WESTERN ATLANTIC. BROAD UPPER RIDGE NOW IN PLACE OVER MOST
OF THE SOUTHERN HALF OF THE COUNTRY.
AT JET LEVEL...MODELS START OUT FINE. AT MID LEVELS...THE CANADIAN
AND GFS WERE DOING A LITTLE BETTER THAN THE NAM AND ECMWF. THE ECMWF
WAS DOING A LITTLE BETTER THAN THE SREF/GFS/NAM ON THE SURFACE WIND
AND PRESSURE FIELD. THE SREF/ECMWF/NAM WERE DOING A LITTLE BETTER
THAN THE REST OF THE OUTPUT ON THE LOW LEVEL THERMAL FIELD.
WEDNESDAY NIGHT...RIGHT REAR QUADRANT OF JET CONTINUES ACROSS THE
NORTHERN HALF OF THE AREA THROUGH THE NIGHT ALTHOUGH IT WEAKENS A
LITTLE LATER IN THE NIGHT. BY LATE IN THE AFTERNOON THE FRONT HAS
SAGGED DOWN THROUGH ABOUT THE WHOLE AREA EXCEPT MAYBE FOR THE
SOUTHERN FRINGE. MID LEVEL SHORTWAVE/LIFT MOVE AFFECT THE
NORTHWEST HALF OF THE AREA THROUGH MIDDLE OF THE NIGHT BEFORE
MOVING OUT OF THE NORTHERN PORTION DURING THE OVERNIGHT HOURS. SO
THE NORTHWEST HALF OF THE AREA WILL HAVE THE HIGHEST POPS
ESPECIALLY THE FAR WEST AND NORTH.
THURSDAY/THURSDAY NIGHT... SHORTWAVE TROUGHS IN NORTHWEST FLOW IS
ALWAYS A TRICKY AND POTENTIALLY ACTIVE SETUP FOR THE AREA. THERE
LOOKS TO BE SOME WEAK LIFT FROM THE RIGHT REAR QUADRANT DURING THE
AFTERNOON. MAIN JET LOOKS TO STAY NORTH OF THE AREA DURING THE
NIGHT. THE FRONT INITIALLY STAYS CLOSE TO THE SOUTHERN PORTION OF
THE AREA BEFORE MOVING EVEN FARTHER SOUTH.
MULTIPLE SHORTWAVE TROUGHS MAKE AFTERNOON AND NIGHTTIME
PRECIPITATION FORECAST MESSY. ONE SHORTWAVE WILL AFFECT THE
SOUTHEAST PORTION OF THE AREA DURING THE AFTERNOON AS ANOTHER WAVE
APPROACHES THE FAR WEST. ALSO POST FRONTAL UPSLOPE OR THE
PROXIMITY OF THE BOUNDARY TO THE WESTERN PORTION OF THE AREA WILL
HELP DEVELOP STORMS. SO AT THIS TIME WILL HAVE SLIGHT CHANCE TO
LOW CHANCE POPS ALONG THE SOUTHEAST AND WESTERN PORTIONS OF THE
AREA.
FOR THE NIGHT...A DECENT BAROCLINIC ZONE LOOKS TO MOVE ACROSS IN
ADVANCE OF A FEW SHORTWAVE TROUGHS. ONE SHORTWAVE TROUGH MOVES
ACROSS THE SOUTHWEST PORTION WITH ANOTHER MOVING ACROSS THE NORTHERN
PORTION. COMBINATION OF THE BAROCLINIC ZONE AND FAVORABLE THETA-E
LAPSE RATES SHOULD ALLOW FOR A GOOD RESPONSE TO THE LIFT. SO CHANCE
POPS WILL TRANSITION FROM NORTHWEST TO SOUTHEAST DURING THIS TIME.
SEE THE POTENTIAL FOR THE POPS TO BE RAISED FROM THIS.
AS STATED ABOVE MOST IF NOT ALL OF THE AREA WILL BE IN POST FRONTAL
UPSLOPE FLOW AND LINGERING CLOUD COVER. AS A RESULT THE HIGH
TEMPERATURES WILL BE COOLER. DEPENDING ON HOW LONG LOW LEVEL CLOUD
COVER LASTS...TEMPERATURES MAY NEED TO BE MADE EVEN COOLER THAN WHAT
IS IN THERE NOW.
FRIDAY...MAIN JET REMAINS NORTH OF THE AREA. DECENT BAROCLINIC ZONE
AND COLD AIR ADVECTION WILL CONTINUE TO MOVE ACROSS DURING THE DAY.
SHORTWAVES WILL ROTATE THROUGH THE NORTHERLY FLOW ALOFT WITH A
MODERATELY STRONG SHORTWAVE MOVING THROUGH FROM LATE IN THE
MORNING THROUGH MID AFTERNOON. SO HAVE SLIGHT TO CHANCE POPS FOR
NOW.
COLD AIR ALOFT...POST FRONTAL SURFACE WINDS...CLOUD COVER AND
PRECIPITATION WILL HELP KEEP TEMPERATURES FROM RISING TOO MUCH.
TEMPERATURES LOOK TO BE COOLER THAN THE PREVIOUS DAY BUT ONCE AGAIN
THE POTENTIAL IS THERE AGAIN TO HAVE TO MAKE THESE TEMPERATURES
COOLER.
FRIDAY NIGHT THROUGH TUESDAY...PATTERN WILL AMPLIFY THROUGH THE
PERIOD WITH A RATHER STRONG/SHARP UPPER RIDGE TO OUR WEST. MODELS
ARE IN GOOD AGREEMENT WITH THIS. PERIODIC SHORTWAVE TROUGHS ALONG
WITH THE ASSOCIATED SURFACE FEATURES WILL MOVE THROUGH IN THE
NORTHWEST TO EVENTUALLY NORTH FLOW ALOFT.
HARD TO RULE OUT PRECIPITATION IN THIS PERIOD. AT THIS TIME...IT
LOOKS LIKE ISOLATED AFTERNOON AND EVENING CONVECTION...MAINLY IN MY
WESTERN/NORTHERN PORTIONS THROUGH THE PERIOD. THE CRH_INIT DEPICTED
THIS SCENARIO NICELY AND DID NOT CHANGE THE POPS THAT I WAS GIVEN.
THE ONLY TRULY DRY PERIOD LOOKS TO BE MONDAY AND MONDAY NIGHT.
TEMPERATURES SHOULD NOT GET TOO HOT OR WAY ABOVE NORMAL DUE TO THE
NORTHERLY FLOW ALOFT AND PERSISTENT EASTERLY SURFACE WINDS OF SOME
SORT. THIS IS ALSO DEPICTED NICELY BY THE INIT AND DID NOT CHANGE.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z WEDNESDAY EVENING)
ISSUED AT 522 PM MDT TUE JUN 23 2015
VFR CONDITIONS ARE EXPECTED AT KGLD AND KMCK THIS EVENING AND
OVERNIGHT. THERE IS A SLIGHT CHANCE OF THUNDERSTORMS THIS EVENING
AT KGLD. LATER TONIGHT SOME STRATUS MAY MOVE INTO KMCK AS A WARM
FRONT LIFTS TO THE NORTH ACROSS KANSAS. VFR CONDITIONS ARE
EXPECTED WEDNESDAY AT BOTH SITES.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
SHORT TERM...DR
LONG TERM...BULLER
AVIATION...FS
...UPDATE TO AVIATION FORECAST DISCUSSION...
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 323 AM CDT TUE JUN 23 2015
AN UPPER LEVEL RIDGE CONTINUED TO B CENTERED ACROSS THE SOUTHERN
PLAINS AND EXTEND WEST INTO THE SOUTHWEST US. A NEARLY ZONAL MID AND
UPPER LEVEL JET EXTENDED ACROSS THE NORTHERN AND CENTRAL PLAINS.
A SURFACE COLD FRONT HAS PUSHED SOUTH OF THE CWA AND WAS LOCATED
FROM NORTH OF CNU AND EXTENDED WEST-SOUTHWEST TO SOUTH OF P28, THEN
WEST TO NORTH OF LBL. THIS FRONT WILL BECOME STATIONARY THROUGH THE
MORNING HOURS AND SLOWLY MOVE NORTH THROUGH THE DAY TUESDAYS.
ONCE AGAIN THE MODEL SOLUTIONS DIFFER ON QPF ACROSS THE CWA AND
MESOSCALE MODELS SUCH AS THE WRF SHOW NO QPF ACROSS THE CWA.
EARLY THIS MORNING A FEW SHOWERS WERE BEGINNING TO DEVELOP ACROSS
CENTRAL KS IN RESPONSE TO WEAK ISENTROPIC LIFT ALOFT. THE HRRR AND
NAM MODELS CONTINUE TO SHOW ELEVATED THUNDERSTORMS DEVELOPING
ACROSS CENTRAL KS, THEN MOVING EAST-NORTHEAST ACROSS THE NORTHERN
HALF OF THE CWA. THEREFORE, I`LL KEEP A SLIGHT RISK FOR SHOWERS
AND THUNDERSTORMS ACROSS THE NORTHERN HALF OF THE CWA THROUGH THE
DAY. AT THIS TIME MOST OF THE STORMS LOOK TO BE ELEVATED. IF A
SURFACE BASED STORM WERE TO DEVELOP THIS AFTERNOON IT COULD BECOME
SEVERE OR STRONG GIVEN MLCAPES OF 2,000 J/KG AND 30 KTS EFFECTIVE
SHEAR. HOWEVER, THE WARM TEMPERATURES ALOFT WILL SHOULD LIMIT HAIL
SIZE FROM ANY ORGANIZED STORM.
HIGHS TODAY WILL BE DEPENDENT ON HOW FAST THE FRONT MOVES NORTH. THE
FRONT IS PROGGED TO BE SOUTH OF I-70 BY LATE THIS AFTERNOON. THE
SOUTHERN COUNTIES OF THE CWA MAY SEE LOWER TO MID 90S WITH MID TO
UPPER 80S ALONG THE I-70 CORRIDOR AND LOWER 80S ALONG THE NE BORDER.
TONIGHT, AS THE WARM FRONT MOVES NORTH TO THE NE BORDER. THE BEST
ISENTROPIC LIFT WILL OCCUR NORTH OF THE CWA ACROSS NE. I KEPT SLIGHT
CHANCE POPS IN THE EXTREME NORTHERN COUNTIES OF THE CWA IN CASE
SHOWERS AND STORMS TRY TO BUILD SOUTHWARD TO THE FRONT. ANY COMPLEX
OF STORMS THAT DEVELOP ACROSS THE HIGH PLAINS OF NORTHEAST CO AND
WESTERN NE SHOULD MOVE EAST ACROSS CENTRAL AND SOUTHERN NE.
OVERNIGHT LOWS WILL ONLY DROP BACK TO THE UPPER 60S TO LOWER 70S.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 323 AM CDT TUE JUN 23 2015
TOMORROW THE UPPER RIDGE BEGINS TO PROGRESS EASTWARD WHILE THE
QUASIZONAL FLOW ACROSS THE NORTHERN US REMAINS ACTIVE WITH SHORTWAVE
ACTIVITY. ALTHOUGH THESE SHORTWAVES WILL TRACK NORTH OF THE AREA
THEY WILL LIKELY SEND A FRONT SOUTHWARD ACROSS THE REGION DURING THE
DAY THURSDAY, WHICH WOULD PLACE THE FORECAST AREA UNDER THE THERMAL
RIDGE AXIS TOMORROW. HIGH TEMPERATURES LOOK TO REACH THE MID TO
UPPER 90S WITH THE HIGHEST TEMPERATURES LOCATED IN CENTRAL KS CLOSER
TO THE THERMAL RIDGE AHEAD OF THE FRONTAL ZONE. DEWPOINT ARE
FORECAST TO BE IN THE UPPER 60S TO LOW 70S CAUSING HEAT INDICES TO
REACH THE LOW 100S. ON THURSDAY THE FRONT SLIDES THROUGH NORTHEAST
KS BRINGING THE CHANCE FOR SCATTERED THUNDERSTORMS MOST LIKELY
DURING PEAK HEATING. DEPENDING ON THE FRONTAL PLACEMENT THERE COULD
BE A DECENT TEMPERATURE GRADIENT ACROSS THE AREA WITH THE NORTHERN
COUNTIES IN THE 80S AND SOUTHERN COUNTIES IN THE 90S. STORM COVERAGE
SHOULD BE DETERMINED BY WHERE THE CAP BREAKS AND IF CONVERGENCE
ALONG THE FRONT CAN SUPPLY ENOUGH LIFT. BEHIND THE FRONT THE
MID/UPPER LEVEL TROUGH BEGINS TO DIG INTO THE CENTER OF THE COUNTRY.
THIS WILL ENHANCE THE LIFT OVER THE FRONTAL ZONE, AND SUPPORT A
BETTER CHANCE OF PRECPITITATION THURSDAY NIGHT INTO FRIDAY.
NORTHWEST FLOW ALOFT THEN BECOMES MORE ESTABLISHED THROUGH THE REST
OF THE WEEK BRINGING COOLER TEMPERATURES INTO THE REGION. ALSO, THE
MODELS ARE HINTING AT SHORTWAVES TRACKING OUT OF CANADA AND OVER THE
UPPER MIDWEST AND GREAT LAKES REGION BRINGING MORE CHANCE FOR
SHOWERS AND STORMS. THIS ACTIVITY APPEARS TO OCCUR LATE WEEKEND INTO
EARLY NEXT WEEK.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON)
ISSUED AT 1217 PM CDT TUE JUN 23 2015
TAFS SHOULD REMAIN VFR FOR THE ENTIRE PERIOD. THERE IS A SMALL
CHANCE OF AN ISOLATED SHOWER OR THUNDERSTORM NEAR THE TERMINALS
BUT FOR THE MOST PART SHOULD STAY TO THE NORTH. CONFIDENCE IN A
STORM HAPPENING NEAR THE TAF SITES IS LOW. MOST TRENDS AND
GUIDANCE SUGGESTS THE BEST POTENTIAL REMAINS OFF TO THE NORTH AND
NORTHEAST NEAR THE KANSAS/NEBRASKA BORDER. EXPECT WINDS TO VEER TO
THE SOUTH BY MORNING. GOOD CONFIDENCE IN THE OVERALL SYNOPTIC
SETUP WITH THIS AS WELL AS GENERAL TIME FRAMES.
&&
.TOP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...GARGAN
LONG TERM...SANDERS
AVIATION...DRAKE
AREA FORECAST DISCUSSION
NWS GOODLAND KS
327 PM MDT MON JUN 22 2015
.SHORT TERM...(THIS AFTERNOON THROUGH TUESDAY)
ISSUED AT 222 PM MDT MON JUN 22 2015
WV IMAGERY AND RAP H5 ANALYSIS SHOWS BROAD 597DM RIDGE IN PLACE
ACROSS THE SOUTHER PLAINS WITH ZONAL FLOW ACROSS THE NORTHERN US.
NORTHERN JET STREAM IS ACROSS THE NORTHERN PLAINS...WITH POSITIVELY
TILTED TROUGH OVER NORTHERN MINNESOTA. THERE IS A WEAK SHORTWAVE
OVER NORTH CENTRAL COLORADO WITH MINOR HEIGHT FALLS.
THIS AFTERNOON-EVENING...VERY HIGH CINH/CAP WILL BE IN PLACE THIS
AFTERNOON AND EVENING. FRONT IS NOW ALONG THE SOUTHERN EDGE OF
CWA...WITH PRIMARY CONVERGENCE ALONG PRE FRONTAL TROUGH IN SW
KANSAS. AT THIS POINT IT SEEMS UNLIKELY THE CAP WILL WEAKEN OR
BREAK THIS AFTERNOON OR EARLY THIS EVENING...WITH ANY INITIATION
LIMITED TO SW KANSAS OR HIGHER TERRAIN IN COLORADO.
TONIGHT-TUESDAY MORNING...SHORTWAVE TROUGH OVERNIGHT COULD COMBINE
WITH WEAK H85-H7 WAA ACROSS NE COLORADO TO PRODUCE A FEW ELEVATED
THUNDERSTORMS NEAR STALLED FRONTAL ZONE. GUIDANCE IS SHOWING PRECIP
SIGNAL IN THIS AREA SPREADING EASTWARD. MOISTURE PROFILES ARE
UNIMPRESSIVE WITH LOW MIXING RATIOS/HIGH TD DEPRESSIONS THAT WOULD
LIKELY LIMIT CONFIDENCE IN INITIATION OR COVERAGE. IF THUNDERSTORMS
WERE TO DEVELOP MODERATE CAPE AND GOOD EFFECTIVE SHEER COULD SUPPORT
SEVERE THUNDERSTORM DEVELOPMENT. I AM JUST NOT SURE IF WE ARE GOING
TO SEE ANYTHING DEVELOP...SO I KEPT POPS LIMITED TO 20. GUIDANCE
SHOWS GOOD BL MOISTURE ADVECTING WIT EASTERLY FLOW NORTH OF
FRONT...POSSIBLY POOLING ALONG FRONTAL ZONE IN EASTERN COLORADO LATE
TONIGHT/EARLY TUESDAY MORNING. I DECIDED TO KEEP OUT MENTION OF FOG
WITH GUIDANCE KEEPING VISIBILITIES HIGH...HOWEVER THIS SHOULD BE
MONITORED.
TUESDAY...HI RES MODELS GENERALLY SHOW ANY THUNDERSTORM ACTIVITY
TRANSITIONING EAST OF THE CWA BY MIDDAY TUESDAY WITH MEAN
FLOW...AND I KEPT THIS TIMING IN PLACE. ANOTHER WEAK
SHORTWAVE/RIPPLE WITHIN MEAN FLOW BEGINS TO APPROACH THE CWA FROM
THE WEST TUESDAY AFTERNOON. FRONT WILL BE IN THE PROCESS OF
LIFTING OVER THE CWA...SO WE COULD SEE INCREASING SURFACE
CONVERGENCE THROUGH THE LATE AFTERNOON...WHICH COULD BE ENOUGH TO
WEAKEN THE DAYTIME CAP. MODELS ARE SHOWING A FAIRLY LARGE SPREAD
IN FRONT POSITION/TIMING...SO HIGH TEMPS AND THIS POTENTIAL FOR
INITIATION IS UNCERTAIN. BEST MODEL CONSENSUS IS ON DEVELOPMENT
BY LATE AFTERNOON IN THE SW...THOUGH THIS COULD STILL BE A LITTLE
EARLY BASED ON MODEL TIMING OF BEST UPPER LEVEL FORCING/HEIGHT
FALLS. WITH FRONTAL ZONE OVER CWA...THERE COULD BE BETTER SHEER
PROFILES WITH VEERING ALONG FRONTAL ZONE AND ESPECIALLY IN THE
WEST NEAR SURFACE TROUGH. RESULT COULD BE A BETTER CHANCE FOR
SUPERCELL DEVELOPMENT IF THUNDERSTORMS DO DEVELOP.
.LONG TERM...(TUESDAY NIGHT THROUGH MONDAY)
ISSUED AT 324 PM MDT MON JUN 22 2015
FORECAST PROBLEMS WILL BE CHANCES OF THUNDERSTORMS THROUGH THURSDAY
AND HOW HOT DOES IT GET. SATELLITE SHOWING A PROGRESSIVE/NEAR ZONAL
FLOW FROM THE PACIFIC INTO THE WESTERN ATLANTIC. BROAD UPPER RIDGE
NOW IN PLACE OVER MOST OF THE SOUTHERN HALF OF THE COUNTRY.
AT JET LEVEL...MODELS STARTED OUT FINE. AT MID LEVELS...THE GFS AND
CANADIAN WERE DOING A LITTLE BETTER THAN THE REMAINING OUTPUT. THE
ECMWF WAS DOING A LITTLE BETTER THAN THE NAM. THE GFS...CANADIAN...
AND THE ECMWF WERE DOING THE BEST ON THE LOW LEVEL THERMAL FIELD.
TUESDAY NIGHT...MAIN JET WELL NORTH. POSSIBLY A WEAK REAR QUADRANT
THAT MOVES ACROSS NEAR OR JUST NORTH OF OUR AREA. SURFACE TROUGH
RESIDES OVER THE FAR WESTERN PORTION OF THE AREA LATE IN THE
AFTERNOON/EARLY EVENING. AT THE SAME TIME A SHORTWAVE TROUGH WILL
BEGIN AFFECTING THE FAR WEST LATE IN THE DAY AND THEN MOVE ACROSS
THE AREA THROUGH THE REMAINDER OF THE NIGHT. PROBLEM IN THE
BEGINNING COULD BE IF THE CAP IS TOO STRONG PLUS THE MODELS DIFFER
ON HOW STRONG THE MID LIFT WILL BE. MODEL QPF IS NOT OVERLY
IMPRESSIVE BUT IT DOES LOOK LIKE WE SHOULD BE GETTING MORE THAN WHAT
IS CURRENTLY SHOWN. CHOSE TO PLAY IT CONSERVATIVELY AND ONLY GO
SLIGHT CHANCE AT THIS TIME.
WEDNESDAY/WEDNESDAY NIGHT...A LOT OF MODEL DIFFERENCES START SHOWING
UP. A WEAKER RIGHT REAR QUADRANT STARTS AFFECTING THE NORTHERN THIRD
TO HALF OF THE AREA DURING THE AFTERNOON INTO AT LEAST THE EVENING
AND POSSIBLY INTO THE OVERNIGHT HOURS DEPENDING ON WHICH MODEL YOU
CHOOSE. A SHORTWAVE TROUGH AND ITS SURFACE REFLECTION MOVE INTO THE
NORTHWEST OF THE AREA BY 18Z AND THEN PROGRESS IT SOUTH AND EAST
THROUGH THE AREA.
PROBLEM IS IN HOW AGGRESSIVE THEY ARE IN MOVING THE FRONT THROUGH.
THE NAM IS THE FASTEST WITH THE GFS MUCH SLOWER AND ONLY ABOUT
HALF WAY THROUGH THE AREA BY LATE IN THE DAY. THE ECMWF IS
SLIGHTLY SLOWER THAN THE NAM. AT THE SAME TIME THE MID LEVEL
TEMPERATURES ARE NEAR PLUS 15. SO WHERE WILL THE SURFACE FOCUS BE
AND IF THE CAP WILL BREAK. ALSO THE STRENGTH OF THE MID LIFT IS IN
QUESTION. AGAIN DUE TO A LOT OF MODEL DIFFERENCE ON TIMING AND
STRENGTH OF FEATURES...NOT A LOT OF CONFIDENCE IN WHAT WILL
HAPPEN. SO ONCE AGAIN CHOSE ONLY TO GO SLIGHT CHANCE BUT IF BETTER
MODEL AGREEMENT WOULD HAPPEN WOULD FEEL A HIGHER CHANCE IS
DESERVED.
DUE TO THE BIG MODEL DIFFERENCES IN WHERE THE BOUNDARY...THERE IS A
HUGE DIFFERENCE IN HOW WARM THEY MAKE IT. CHOSE TO GO IN THE MIDDLE
AND CLOSER TO THE OUTPUT THAT HAS BEEN DOING BETTER RECENTLY.
THURSDAY...DIFFERENCE IN FRONTAL POSITION CONTINUE. MAJORITY OF THE
OUTPUT WOULD SUPPORT THE FRONT BEING A LITTLE FURTHER SOUTH OF THE
FORECAST AREA. SO FELT BETTER ABOUT GOING COOLER. PROXIMITY OF THE
BOUNDARY AND MID LEVEL LIFT ROUGHLY ALONG THE SOUTHERN AND WESTERN
HOURS SUPPORT HAVING THE AFTERNOON POPS IN THE SOUTH AND WEST BUT
NOT VERY CONFIDENT.
THURSDAY NIGHT THROUGH MONDAY...MODELS START THE AMPLIFICATION
PROCESS TO A STRONG WESTERN RIDGE AND EASTERN CONUS TROUGH. FLOW
BECOMES SHIFTS MORE TOWARD THE NORTH BY THE END OF THE PERIOD.
MODELS HAVING A LOT OF DIFFERENCE IN HOW THEY HANDLE THE POSITION
OF WHERE THE SURFACE BOUNDARY ENDS UP. MORE THAN LIKELY WILL
INITIALLY HAVE THE FRONT STAY OR START JUST TO THE SOUTH OF THE
FORECAST AREA AND THEN WILL HAVE ADDITIONAL COLD INTRUSIONS.
DID NOT MAKE ANY CHANGES TO WHAT THE CRH_INIT GRIDS GAVE ME DUE TO
THE INITIAL UNCERTAIN ABOUT THE SURFACE FEATURES. THE MOST ACTIVE
AND WET PART OF THE PERIOD WILL BE THURSDAY NIGHT INTO SATURDAY
NIGHT. AFTER THAT IT BECOMES DRIER AS THE RIDGE EXERTS ITS
INFLUENCE ALONG WITH THE DRIER NORTHERLY FLOW. ONLY ISOLATED
PRECIPITATION IS EXPECTED FROM SUNDAY INTO MONDAY. TEMPERATURES
WILL NOT WARM UP TOO MUCH DUE TO THE NORTHERLY FLOW. MAY BE
POSSIBLE THAT TEMPERATURES MAY NEED TO BE LOWERED A LITTLE AS WE
GET CLOSER TO THIS PERIOD.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON)
ISSUED AT 1130 AM MDT MON JUN 22 2015
VFR CONDITIONS ARE CURRENTLY EXPECTED TO PREVAIL AT BOTH KGLD AND
KMCK TERMINALS THROUGH THE TAF PERIOD. THERE COULD BE A BRIEF
PERIOD OF 2500-3500 KFT CIGS AT KGLD BETWEEN 10-15Z...HOWEVER
BETTER LOW LEVEL MOISTURE POOLING WILL BE ACROSS EASTERN COLORADO
AND CONFIDENCE IS TOO LOW FOR INCLUSION. GUIDANCE CONTINUES TO
SHOW POSSIBILITY OF ISOLATED-SCATTERED THUNDERSTORMS LATE TONIGHT
PRIMARILY ACROSS SW NEBRASKA. INITIATION AND COVERAGE ARE BOTH
QUESTIONS...AND CONFIDENCE IN IMPACT AT EITHER TERMINAL IS TOO LOW
FOR INCLUSION IN TAFS.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
SHORT TERM...DR
LONG TERM...BULLER
AVIATION...DR
AREA FORECAST DISCUSSION
NWS GOODLAND KS
222 PM MDT MON JUN 22 2015
.SHORT TERM...(THIS AFTERNOON THROUGH TUESDAY)
ISSUED AT 222 PM MDT MON JUN 22 2015
WV IMAGERY AND RAP H5 ANALYSIS SHOWS BROAD 597DM RIDGE IN PLACE
ACROSS THE SOUTHER PLAINS WITH ZONAL FLOW ACROSS THE NORTHERN US.
NORTHERN JET STREAM IS ACROSS THE NORTHERN PLAINS...WITH POSITIVELY
TILTED TROUGH OVER NORTHERN MINNESOTA. THERE IS A WEAK SHORTWAVE
OVER NORTH CENTRAL COLORADO WITH MINOR HEIGHT FALLS.
THIS AFTERNOON-EVENING...VERY HIGH CINH/CAP WILL BE IN PLACE THIS
AFTERNOON AND EVENING. FRONT IS NOW ALONG THE SOUTHERN EDGE OF
CWA...WITH PRIMARY CONVERGENCE ALONG PRE FRONTAL TROUGH IN SW
KANSAS. AT THIS POINT IT SEEMS UNLIKELY THE CAP WILL WEAKEN OR
BREAK THIS AFTERNOON OR EARLY THIS EVENING...WITH ANY INITIATION
LIMITED TO SW KANSAS OR HIGHER TERRAIN IN COLORADO.
TONIGHT-TUESDAY MORNING...SHORTWAVE TROUGH OVERNIGHT COULD COMBINE
WITH WEAK H85-H7 WAA ACROSS NE COLORADO TO PRODUCE A FEW ELEVATED
THUNDERSTORMS NEAR STALLED FRONTAL ZONE. GUIDANCE IS SHOWING PRECIP
SIGNAL IN THIS AREA SPREADING EASTWARD. MOISTURE PROFILES ARE
UNIMPRESSIVE WITH LOW MIXING RATIOS/HIGH TD DEPRESSIONS THAT WOULD
LIKELY LIMIT CONFIDENCE IN INITIATION OR COVERAGE. IF THUNDERSTORMS
WERE TO DEVELOP MODERATE CAPE AND GOOD EFFECTIVE SHEER COULD SUPPORT
SEVERE THUNDERSTORM DEVELOPMENT. I AM JUST NOT SURE IF WE ARE GOING
TO SEE ANYTHING DEVELOP...SO I KEPT POPS LIMITED TO 20. GUIDANCE
SHOWS GOOD BL MOISTURE ADVECTING WIT EASTERLY FLOW NORTH OF
FRONT...POSSIBLY POOLING ALONG FRONTAL ZONE IN EASTERN COLORADO LATE
TONIGHT/EARLY TUESDAY MORNING. I DECIDED TO KEEP OUT MENTION OF FOG
WITH GUIDANCE KEEPING VISIBILITIES HIGH...HOWEVER THIS SHOULD BE
MONITORED.
TUESDAY...HI RES MODELS GENERALLY SHOW ANY THUNDERSTORM ACTIVITY
TRANSITIONING EAST OF THE CWA BY MIDDAY TUESDAY WITH MEAN
FLOW...AND I KEPT THIS TIMING IN PLACE. ANOTHER WEAK
SHORTWAVE/RIPPLE WITHIN MEAN FLOW BEGINS TO APPROACH THE CWA FROM
THE WEST TUESDAY AFTERNOON. FRONT WILL BE IN THE PROCESS OF
LIFTING OVER THE CWA...SO WE COULD SEE INCREASING SURFACE
CONVERGENCE THROUGH THE LATE AFTERNOON...WHICH COULD BE ENOUGH TO
WEAKEN THE DAYTIME CAP. MODELS ARE SHOWING A FAIRLY LARGE SPREAD
IN FRONT POSITION/TIMING...SO HIGH TEMPS AND THIS POTENTIAL FOR
INITIATION IS UNCERTAIN. BEST MODEL CONSENSUS IS ON DEVELOPMENT
BY LATE AFTERNOON IN THE SW...THOUGH THIS COULD STILL BE A LITTLE
EARLY BASED ON MODEL TIMING OF BEST UPPER LEVEL FORCING/HEIGHT
FALLS. WITH FRONTAL ZONE OVER CWA...THERE COULD BE BETTER SHEER
PROFILES WITH VEERING ALONG FRONTAL ZONE AND ESPECIALLY IN THE
WEST NEAR SURFACE TROUGH. RESULT COULD BE A BETTER CHANCE FOR
SUPERCELL DEVELOPMENT IF THUNDERSTORMS DO DEVELOP.
.LONG TERM...(THURSDAY THROUGH SUNDAY)
ISSUED AT 227 AM MDT MON JUN 22 2015
QUASI ZONAL UPPER LEVEL FLOW WILL START OUT THE LONG TERM FORECAST
PERIOD ON THURSDAY...WITH THE MAIN JET STREAM WELL TO THE NORTH OF
THE TRI STATE AREA. UPPER LEVEL HIGH PRESSURE WILL REMAIN OVER THE
FORECAST AREA WITH WEAK STEERING WINDS UNTIL FRIDAY WHERE THE UPPER
FLOW PATTERN BECOMES MORE AMPLIFIED WITH A RIDGE BUILDING IN THE
WESTERN PORTION OF THE CONUS AND A TROUGH BUILDING IN THE EASTERN
THIRD OF THE CONUS. TRANSIENT FLOW BETWEEN THE UPPER HIGH AND UPPER
LOW WILL BE POSITIONED OVER THE HIGH PLAINS REGION FOR THE WEEKEND.
ALTHOUGH THERE WILL BE A LACK OF A STRONG JET STREAM IN THE PROFILE
ACROSS THE FORECAST AREA...ECMWF/GFS FORECASTS INDICATE A WEAK
SHORTWAVE TROUGH POSITIONED OVER EASTERN COLORADO AND WESTERN KANSAS
DURING THE AFTERNOON ON THURSDAY...WHICH WILL BRING SOME CHANCES FOR
AFTERNOON SHOWERS AND THUNDERSTORMS. GFS MODEL SOUNDINGS SHOW STEEP
UPPER LEVEL LAPSE RATES AND GOOD MOISTURE IN THE PROFILE...SO ANY
LIFT FROM THE WEAK SHORTWAVE TROUGH IN COMBINATION WITH STRONG
SURFACE HEATING WILL HELP THUNDERSTORM DEVELOPMENT.
A WEAK COOL FRONT WILL PUSH THROUGH THE AREA FRIDAY...BUT SURFACE
UPSLOPE FLOW WILL ADVECT MOISTURE INTO THE REGION FROM THE EAST WITH
SURFACE DEW POINTS REACHING THE MID TO UPPER 50S. AS A RESULT WITH
A MORE NORTHWESTERLY FLOW AT THE MID LEVELS...SHOWERS AND ISOLATED
THUNDERSTORMS ARE POSSIBLE FRIDAY NIGHT INTO SATURDAY MORNING.
THE DEVELOPMENT OF A SURFACE TROUGH SATURDAY AFTERNOON WILL KEEP
SURFACE WINDS VARIABLE FOR THE REST OF THE PERIOD. WITH LACK OF
SURFACE MOISTURE ADVECTION OR THE PRESENCE OF ANY FORCING
MECHANISMS...CONFIDENCE FOR OCCURRING PRECIPITATION IS SHAKY AT THIS
POINT. FORECAST CONSENSUS INDICATED AT LEAST SOME SLIGHT CHANCES
FOR PRECIPITATION...SO KEPT POPS AS IS FOR THE LATER PORTION OF THIS
FORECAST PERIOD.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON)
ISSUED AT 1130 AM MDT MON JUN 22 2015
VFR CONDITIONS ARE CURRENTLY EXPECTED TO PREVAIL AT BOTH KGLD AND
KMCK TERMINALS THROUGH THE TAF PERIOD. THERE COULD BE A BRIEF
PERIOD OF 2500-3500 KFT CIGS AT KGLD BETWEEN 10-15Z...HOWEVER
BETTER LOW LEVEL MOISTURE POOLING WILL BE ACROSS EASTERN COLORADO
AND CONFIDENCE IS TOO LOW FOR INCLUSION. GUIDANCE CONTINUES TO
SHOW POSSIBILITY OF ISOLATED-SCATTERED THUNDERSTORMS LATE TONIGHT
PRIMARILY ACROSS SW NEBRASKA. INITIATION AND COVERAGE ARE BOTH
QUESTIONS...AND CONFIDENCE IN IMPACT AT EITHER TERMINAL IS TOO LOW
FOR INCLUSION IN TAFS.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
SHORT TERM...DR
LONG TERM...MK
AVIATION...DR
AREA FORECAST DISCUSSION
NWS TOPEKA KS
637 AM CDT Mon Jun 22 2015
...Update to aviation forecast discussion...
.SHORT TERM...(Today and Tonight)
Issued at 325 AM CDT MON JUN 22 2015
A broad upper level ridge continues to extend from the southwestern
US east into the southern plains. An upper level trough was moving
eastward across the northern plains and southern Canada. A broad
band of stronger mid and upper level westerly flow continued on the
north side of the upper level ridge across the central and northern
plains.
As the northern plains H5 trough moves east into the upper Midwest
and northern Great Lakes states, a surface cold front across SD will
move southward across NE and into northern KS by late this afternoon.
A surface and 850mb trough extended from an area of low pressure
across southern SD, southwest across western KS. The surface/850mb
trough will slowly shift east across eastern NE into central KS
during the late afternoon hours. Southwesterly 850mb winds will
continue to advect deep moisture and warm air northeast across the
CWA. south-southwest winds will increase by the mid morning hours to
20 to 30 MPH with gusts to 30 to 40 MPH. Forecast soundings show
boundary layer mixing to be around 850mb across the eastern counties
of the CWA with the mixed boundary layer reaching around 800mb
across the southwest counties. Given 850mb temps of 24 to 27
degrees, most areas should reach the mid to upper 90s with some 100
degree readings possible across the southwest counties. Given
dewpoints from the upper 60s to lower 70s most area will see heat
indices reach the 104 to 109 degree range this afternoon. Therefore,
I will keep the heat advisory going for this afternoon. The surface
cold front will move into northern counties of the CWA this
afternoon
Once again there are various model solutions to the
location of developing thunderstorms along the surface front late
this afternoon. The ARW, ECMWF and GFS show the CAP holding across
the CWA with the tail end line of storms developing southwest along
the front into northwest MO. The NAM, RAP and NMM show isolated
thunderstorms developing along the front from northeast KS,
southwest into the central counties of the CWA. If thunderstorms do
develop they will be strong to severe given an environment ahead of
the front with 5,000 to 6,000 J/KG of MLCAPE and 30 to 40 KT of sfc
to 6KM effective shear. The primary hazards from any organized
updraft rotating updraft will be large hail, despite the warmer
temperatures aloft, and damaging wind gusts.
The isolated storms should weaken
near sunset as the surface front pushes south of I-70 and then
become stationary. Elevated showers and thunderstorms may redevelop
later Tonight across the CWA as the veered 850mb winds begin to back
to more of a southerly directions, which may provide for isentropic
lift north of the boundary. However, there will not be much upper
level support as an H5 ridge axis begins to amplify across the high
plains. Overnight lows will dip into the mid 60s along the NE border
with lower 70s across east central KS.
.LONG TERM...(Tuesday through Sunday)
Issued at 325 AM CDT MON JUN 22 2015
Some 700-850mb moisture convergence takes place over mainly northern
locations Tuesday north of the front, with modest though somewhat
deep isentropic upglide on 315 and 310K surfaces. Elevated CAPE of
around 2000 J/kg and effective shear of around 40kt progged by NAM
and GFS could support at least brief severe storms. Have dropped
temps a few degrees in increasing agreement in some precip and
cloud, though gradient could easily be much stronger than forecast.
Convergence shifts northeast in the afternoon and evening hours for
diminishing chances. Deep southwest low level flow brings warmer air
back in for Wednesday. Air temps should easily reach the 90s, though
persistent trajectories from the southwest from earlier periods
should keep dewpoints somewhat lower and apparent temps around 100.
Next front sinks south through eastern Kansas Thursday into Friday
with upper ridge beginning to build over the western ConUS. Cooling
mid level temps and deeper moisture should support a more widespread
precip event, with wind fields not supporting much in way of severe
storms. Front continues south in increasingly amplified upper flow
with dropping to below normal levels for the weekend.
&&
.AVIATION...(For the 12Z TAFs through 12Z Tuesday Morning)
Issued at 632 AM CDT MON JUN 22 2015
Expect VFR conditions for the next 24 hours. South-southwest winds
will pick up after 14Z to 15 KTS to 20 KTS...with gusts to 20 KTS
to 25 KTS through the afternoon hours. Isolated thunderstorms may
develop between 00Z-04Z TUE, though the better chances will be
north and northeast of the terminals.
&&
.TOP WATCHES/WARNINGS/ADVISORIES...
HEAT ADVISORY from 1 PM this afternoon to 7 PM CDT this evening
FOR KSZ010>012-020>024-026-034>036-038>040-054>056.
&&
$$
SHORT TERM...Gargan
LONG TERM...65
AVIATION...Gargan
AREA FORECAST DISCUSSION
NWS TOPEKA KS
325 AM CDT Mon Jun 22 2015
.SHORT TERM...(Today and Tonight)
Issued at 325 AM CDT MON JUN 22 2015
A broad upper level ridge continues to extend from the southwestern
US east into the southern plains. An upper level trough was moving
eastward across the northern plains and southern Canada. A broad
band of stronger mid and upper level westerly flow continued on the
north side of the upper level ridge across the central and northern
plains.
As the northern plains H5 trough moves east into the upper Midwest
and northern Great Lakes states, a surface cold front across SD will
move southward across NE and into northern KS by late this afternoon.
A surface and 850mb trough extended from an area of low pressure
across southern SD, southwest across western KS. The surface/850mb
trough will slowly shift east across eastern NE into central KS
during the late afternoon hours. Southwesterly 850mb winds will
continue to advect deep moisture and warm air northeast across the
CWA. south-southwest winds will increase by the mid morning hours to
20 to 30 MPH with gusts to 30 to 40 MPH. Forecast soundings show
boundary layer mixing to be around 850mb across the eastern counties
of the CWA with the mixed boundary layer reaching around 800mb
across the southwest counties. Given 850mb temps of 24 to 27
degrees, most areas should reach the mid to upper 90s with some 100
degree readings possible across the southwest counties. Given
dewpoints from the upper 60s to lower 70s most area will see heat
indices reach the 104 to 109 degree range this afternoon. Therefore,
I will keep the heat advisory going for this afternoon. The surface
cold front will move into northern counties of the CWA this
afternoon
Once again there are various model solutions to the
location of developing thunderstorms along the surface front late
this afternoon. The ARW, ECMWF and GFS show the CAP holding across
the CWA with the tail end line of storms developing southwest along
the front into northwest MO. The NAM, RAP and NMM show isolated
thunderstorms developing along the front from northeast KS,
southwest into the central counties of the CWA. If thunderstorms do
develop they will be strong to severe given an environment ahead of
the front with 5,000 to 6,000 J/KG of MLCAPE and 30 to 40 KT of sfc
to 6KM effective shear. The primary hazards from any organized
updraft rotating updraft will be large hail, despite the warmer
temperatures aloft, and damaging wind gusts.
The isolated storms should weaken
near sunset as the surface front pushes south of I-70 and then
become stationary. Elevated showers and thunderstorms may redevelop
later Tonight across the CWA as the veered 850mb winds begin to back
to more of a southerly directions, which may provide for isentropic
lift north of the boundary. However, there will not be much upper
level support as an H5 ridge axis begins to amplify across the high
plains. Overnight lows will dip into the mid 60s along the NE border
with lower 70s across east central KS.
.LONG TERM...(Tuesday through Sunday)
Issued at 325 AM CDT MON JUN 22 2015
Some 700-850mb moisture convergence takes place over mainly northern
locations Tuesday north of the front, with modest though somewhat
deep isentropic upglide on 315 and 310K surfaces. Elevated CAPE of
around 2000 J/kg and effective shear of around 40kt progged by NAM
and GFS could support at least brief severe storms. Have dropped
temps a few degrees in increasing agreement in some precip and
cloud, though gradient could easily be much stronger than forecast.
Convergence shifts northeast in the afternoon and evening hours for
diminishing chances. Deep southwest low level flow brings warmer air
back in for Wednesday. Air temps should easily reach the 90s, though
persistent trajectories from the southwest from earlier periods
should keep dewpoints somewhat lower and apparent temps around 100.
Next front sinks south through eastern Kansas Thursday into Friday
with upper ridge beginning to build over the western ConUS. Cooling
mid level temps and deeper moisture should support a more widespread
precip event, with wind fields not supporting much in way of severe
storms. Front continues south in increasingly amplified upper flow
with dropping to below normal levels for the weekend.
&&
.AVIATION...(For the 06Z TAFs through 06Z Monday Night)
Issued at 1137 PM CDT SUN JUN 21 2015
For the 06z TAFs, VFR conditions are expected through the period.
Southerly winds will be gusty at times overnight with increasing
winds by mid-morning, resulting in gusts upwards of 25-30kts through
the afternoon. A cold front will sink southward toward the TAF sites
by late afternoon, with winds shifting to the north late afternoon
through the evening hours. With the front slowly pivoting over the
TAF sites Monday evening, could see a couple of hours of variable wind
directions. There is the potential for some isolated to scattered
storms to develop along this boundary late afternoon into the
evening hours, but have not mentioned it in the TAF at this time due
to uncertainty in timing and occurrence. However, this potential
will be monitored for future TAF updates.
&&
.TOP WATCHES/WARNINGS/ADVISORIES...
HEAT ADVISORY from 1 PM this afternoon to 7 PM CDT this evening
FOR KSZ009>012-021>024-026-034>040-054>056.
&&
$$
SHORT TERM...Gargan
LONG TERM...65
AVIATION...Hennecke
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
1207 AM CDT MON JUN 22 2015
...UPDATE TO AVIATION...
.SYNOPSIS...
ISSUED AT 1100 PM CDT SUN JUN 21 2015
WV IMAGERY AND 00Z UPPER AIR ANALYSIS INDICATE A WEAK UPPER LEVEL
RIDGE OF HIGH PRESSURE MOVING EASTWARD ACROSS THE FOUR CORNERS
REGION. MEANWHILE, AN UPPER LEVEL SHORTWAVE TROUGH IS PUSHING
EASTWARD OUT OF THE CANADIAN ROCKIES. NEAR THE SURFACE, A FRONTAL
BOUNDARY IS LIFTING SLOWLY NORTHWARD ACROSS NORTHWEST AND NORTH
CENTRAL KANSAS.
&&
.SHORT TERM...(THIS EVENING THROUGH MONDAY)
ISSUED AT 231 PM CDT SUN JUN 21 2015
THIS MORNINGS UPPER AIR ANALYSIS SHOWED AN UPPER LEVEL RIDGE CONTINUING
TO STRETCH FROM A HIGH CENTERED NEAR THE FOUR CORNERS REGION EASTWARD
ALONG THE KANSAS/OKLAHOMA BORDER INTO THE SOUTHEASTERN STATES. THE
STRONGEST UPPER LEVEL WESTERLY FLOW CONTINUES TO BE LOCATED ACROSS
THE NORTHERN CONUS. TWO SHORTWAVE TROUGHS IN THE WESTERLY FLOW
WERE LOCATED OVER SOUTHERN PORTIONS OF BRITISH COLUMBIA AND ALBERTA
AS WELL AS OVER THE WEST COAST OF OREGON AND FAR NORTHERN CALIFORNIA.
ACROSS THE CENTRAL PLAINS, AN OUTFLOW BOUNDARY THAT WAS DRIVEN SOUTH
INTO WESTERN KANSAS THIS MORNING WAS LIFTING BACK NORTHWARD THIS
AFTERNOON AS SOUTHERLY WINDS WERE RETURNING TO ALL THE OBSERVATION
SITES IN WESTERN AND CENTRAL KANSAS.
OVER THE NEXT 24-36 HOURS, THE UPPER LEVEL HIGH OVER THE SOUTHWEST WILL
SLOWLY PROPAGATE EAST INTO THE CENTRAL/SOUTHERN PLAINS. THE DISTURBANCES
OVER THE PACIFIC NORTHWEST ARE PROGGED TO COME INTO PHASE AND TRACK
EAST ACROSS THE NORTHERN PLAINS INTO THE WESTERN GREAT LAKES BY MONDAY
EVENING. EXPECTING ANOTHER QUIET PERIOD THIS EVENING AND OVERNIGHT.
MOST MODEL SOLUTIONS DO NOT GENERATE ANY PRECIPITATION ACROSS WESTERN
KANSAS THIS EVENING ALTHOUGH THE RAP AND ESPECIALLY THE HRRR DEVELOP
THUNDERSTORMS ALONG AND SOUTH OF I-70 IN CENTRAL KANSAS LATE THIS
AFTERNOON AND EVENING. MODEL SOUNDINGS SHOW A NICE CAPPING INVERSION
AROUND 700 MILLIBARS WHICH SHOULD EFFECTIVELY KEEP A LID ON ANY
CONVECTIVE DEVELOPMENT. WHILE I COULDN`T TOTALLY RULE OUT AN
ISOLATED THUNDERSTORM SIMILAR TO SATURDAY EVENING, WILL LEAVE THE
FORECAST DRY FOR NOW. SOUTHERLY WINDS WILL CONTINUE AROUND 10-20
MPH OVERNIGHT WHICH SHOULD HOLD OVERNIGHT LOWS UP A FEW MORE
DEGREES THAN LAST NIGHT.
ON MONDAY, A WEAK COLD FRONT WILL PUSH SOUTHWARD INTO WEST CENTRAL KANSAS
BY MIDDAY OR EARLY AFTERNOON. THIS COULD HOLD TEMPERATURES BACK A FEW
DEGREES AND HAVE LOWERED HIGHS A FEW DEGREES FROM HAYS THROUGH SYRACUSE
MONDAY AFTERNOON. FARTHER SOUTH OVER THE REMAINDER OF SOUTHWEST KANSAS,
WE SHOULD SEE HIGHS BACK UP TO AROUND 100 DEGREES.
.LONG TERM...(MONDAY NIGHT THROUGH SUNDAY)
ISSUED AT 307 PM CDT SUN JUN 21 2015
UPPER LEVEL RIDGING OVER THE SOUTHERN PLAINS THROUGH MIDWEEK
WILL SHIFT WESTWARD INTO THE ROCKIES BY THURSDAY AND THROUGH THE
WEEKEND WHILE GRADUALLY AMPLIFYING. THIS WILL GENERALLY BE A HOT
PATTERN THROUGH THURSDAY OR FRIDAY, WITH SMALL CHANCES FOR
THUNDERSTORMS NEAR A FRONTAL ZONE ACROSS WEST CENTRAL KANSAS AND
NEAR INTERSTATE 70. GIVEN THE WEAK WINDS AT UPPER LEVELS, THESE
STORMS WILL PROBABLY NOT BE SEVERE, WITH ONLY AN ISOLATED
DAMAGING WIND GUST AND SMALL HAIL. HIGH TEMPERATURES WILL MAINLY
BE IN THE MID TO UPPER 90S THROUGH FRIDAY, WITH LOWS GENERALLY IN
THE UPPER 60S TO LOWER 70S. TEMPERATURES COULD BE SLIGHT COOLER
ALONG INTERSTATE 70 DEPENDING ON THE EXACT LOCATION OF THE FRONTAL
BOUNDARY AND ANY POSSIBLE THUNDERSTORM CLUSTERS PRODUCING COOL
OUTFLOW. AS THE UPPER LEVEL RIDGE RETROGRADES BACK OVER THE WEST
AND AMPLIFIES BY THE WEEKEND, HIGH TEMPERATURES WILL DROP BACK
INTO THE MID 80S TO LOWER 90S STARTING SATURDAY, ALONG WITH A FEW
THUNDERSTORMS AS THE COLD FRONT PASSES FROM THURSDAY NIGHT THROUGH
FRIDAY NIGHT.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT)
ISSUED AT 1205 AM CDT MON JUN 22 2015
VFR CONDITIONS WILL PREVAIL AT ALL TAF SITES THROUGH LATE MONDAY
AFTERNOON. SOUTHERLY WINDS AROUND 15 TO 25KT WILL PERSIST OVERNIGHT
AS A LEE SIDE TROUGH OF LOW PRESSURE REMAINS ANCHORED ACROSS EASTERN
COLORADO. A WEAK COLD FRONT IS THEN EXPECTED TO MOVE SOUTHEAST INTO
WESTERN KANSAS EARLY MONDAY AFTERNOON BEFORE STALLING OUT ACROSS
SOUTHWEST AND CENTRAL KANSAS NEAR THE OKLAHOMA BORDER. WINDS WILL
BECOME NORTH-NORTHEASTERLY 15 TO 25KT BEHIND THE FRONT.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 70 97 72 97 / 10 0 10 0
GCK 69 98 72 96 / 20 0 20 10
EHA 70 97 71 95 / 20 0 10 10
LBL 70 97 71 95 / 10 0 0 0
HYS 70 93 73 97 / 20 10 10 20
P28 72 96 73 95 / 10 0 0 0
&&
.DDC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...JJOHNSON
SHORT TERM...GERARD
LONG TERM...FINCH
AVIATION...JJOHNSON
AREA FORECAST DISCUSSION
NWS LOUISVILLE KY
320 PM EDT Mon Jun 22 2015
.SHORT TERM (Now through Tuesday Night)...
Updated at 300 PM EDT Mon Jun 22 2015
...Strong to Severe Storms Possible Tuesday Afternoon...
Thunderstorms to our north in Michigan our sending plenty of
subsiding cirrus our way this afternoon. Visible satellite imagery
indicates our cumulus field is being held at bay because of this
flow aloft, and latest radar over western KY shows earlier cells are
decaying as well. Cannot rule out an isolated shower surviving in
our southwest.
Latest HRRR indicates a line of storms would fire in southeast
Iowa/northern Illinois and head southeast through the evening,
perhaps getting to our area as just a line of gusty winds or even an
very isolated shower by daybreak Tuesday. Would expect wherever this
boundary sets up to be the focus for further convection by late
morning or early afternoon Tuesday. NAM soundings are very unstable
for the afternoon, and surface temp/dewpoints are in line with what
we expect tomorrow. Soundings show a layer of dry air in the 600-700
mb range, allowing the chance for both larger hail and stronger
downburst winds. Bust potential for this forecast would be just how
many clouds remain from the line that comes through overnight and
how this affects surface temperatures. Clouds over LEX this hour are
keeping temperatures ~5 degrees cooler than areas in the clear! Will
highlight potential for severe wind gusts and hail in the stronger
storms with our hazardous weather outlook.
Again, highs Tuesday will depend greatly on extent of clouds in the
morning. Based on current forecast, expect highs around 90. This
should push heat indices into the mid to upper 90s for most
locations. The best chance to get up to around 100 would be south of
the I-64 corridor and west of a Bardstown to Glasgow line.
.LONG TERM (Wednesday through Monday)...
Issued at 300 PM EDT Mon Jun 22 2015
The synoptic pattern at the start of the long term period will
feature an expansive ridge across the southern CONUS, placing the
Ohio Valley on the periphery of the swift northwest flow found
across much of the northern CONUS. This regime will amplify through
the end of the long term period as the southern ridge breaks down
and a trough builds into the Ohio Valley, bringing some relief from
the precip chances and the hot and humid weather we`ve experienced
as of late.
Generally low-resolution synoptic models are notorious for
struggling with convection and MCS development, so confidence in the
long term period on timing and convective coverage is generally low,
especially Wednesday. That being said, have attempted to best time
the convection using a general model blend and ensemble data. This
method brings just chance pops to the region Wednesday into
Wednesday night, as there does not appear to be any substantial
triggering PV anomaly to spark convection.
By Thursday, the southern ridge will begin to break down as a strong
trough dives into the northern CONUS. Timing as of now keeps much
of the convection just north of the region through much of the
daylight hours on Thursday. Good southwesterly flow ahead of an
area of low pressure coupled with some expected sunshine and 850mb
temps rising to around 20C means Thursday could end up being quite
warm, assuming clouds/precip remain to the north. Have gone with
highs in the low to mid 90s, which coupled with dewpoints in the low
to mid 70s, will push heat index values on either side of 100
degrees.
The trough and associated surface front will slowly push through the
region Thursday night into Friday night. Mid-level flow will be
sufficient to support some strong/severe storms, but the potential
for storms Thursday night may hinder destabilization on Friday given
the expected cloud cover. If we are able to see some sun break out
on Friday, then a few strong/severe storms will be possible. Again,
predictability in the mesoscale details at this timeframe are rather
low, but the strength of the system pushing through does support the
potential for some strong/severe storm development, especially
across southern KY on Friday. Given the slow movement of the front
through the area, we could also have some local flooding issues as
well, so that will be something to continue to monitor.
The passing cold front and building trough aloft will make for
rather pleasant conditions moving in by the weekend. Temperatures
will fall into the upper 70s and lower 80s for highs on Saturday and
Sunday. Conditions should be generally dry Saturday night through
Sunday, as the deeper moisture finally gets shunted to the east with
the passing cold front.
&&
.AVIATION (18Z TAF Update)...
Updated at 115 PM EDT Mon Jun 22 2015
Have the remains of earlier storms over southern Indiana maintaining
mid-level cloudiness over KLEX this hour. Also have cirrus
streaming in from the north, which looks to be squashing convection
across the area, according to latest visible satellite imagery. Have
put in VCSH for KBWG, but not confident the showers to the west will
survive. Low pressure to our west will keep our winds generally from
the southwest this period.
&&
.LMK WATCHES/WARNINGS/ADVISORIES...
KY...NONE.
IN...NONE.
&&
$$
Short Term........RJS
Long Term.........KJD
Aviation..........RJS
AREA FORECAST DISCUSSION
NWS JACKSON KY
217 PM EDT MON JUN 22 2015
.UPDATE...
ISSUED AT 217 PM EDT MON JUN 22 2015
FORECAST IS PRETTY MUCH ON TRACK. IT APPEARS THAT THE HRRR HAS
FINALLY GOTTEN THE TRENDS RIGHT WITH SOME OF THE MORE RECENT
RUNS. SOME ISOLD THUNDERSTORMS ARE BEGINNING TO FIRE ACROSS
SOUTHERN PORTIONS OF OUR CWA. WE CAN EXPECT ADDITIONAL HIT/MISS
TYPE POP UP THUNDERSTORMS THROUGH THE REMAINDER OF THE AFTERNOON.
TWEAKED AFTERNOON HIGHS JUST A BIT. CU FILED HAS DEVELOPED AND A
MORE SIGNIFICANT AREA OF CLOUD COVER DRIFTING SLOWLY ACROSS THE
CENTRAL PORTIONS OF OUR CWA WILL HELP KEEP AFTERNOON HIGHS DOWN
JUST A BIT ACROSS THE MID TO LOWER PORTIONS OF THE KENTUCKY RIVER
VALLEY.
UPDATE ISSUED AT 1130 AM EDT MON JUN 22 2015
UPDATED GRIDS THIS MORNING FOR MOST RECENT HOURLY OBS. ALSO
FRESHENED UP ZONE WORDING AND REMOVED FOG. LITTLE IF ANYTHING
LEFT IN OUR AREA TO INDICATE STORM COMPLEXES ROLLED THROUGH CNTRL
KY LAST NIGHT INTO EARLY THIS MORNING. THE HRRR HINTS AT SOME
REGENERATION OF STORMS ACROSS OUR AREA THIS AFTERNOON ALONG WHAT
MAY BE A WEAK SFC CONVECTIVE BOUNDARY FROM LAST NIGHTS ACTIVITY.
BUT OTHER MODELS HAVE DISCOUNTED THIS POSSIBILITY. ELONGATED RIDGE
FROM THE WEST DOES BEGIN AN ATTEMPT AT NOSING ITS WAY BACK INTO
OUR AREA TODAY WHICH COULD EXPLAIN THE DISCONTINUITY IN NEAR TERM
SOLUTIONS. WILL HAVE TO MONITOR TO SEE IF ANYTHING CAN FIRE. FOR
NOW WENT WITH AN OPTIMISTIC ISOLD POPS FOR THE REMAINDER OF THE
DAY.
UPDATE ISSUED AT 705 AM EDT MON JUN 22 2015
UPSTREAM THUNDERSTORM COMPLEX IS WEAKENING FAST AND PROBABLY WILL
NOT MAKE IT INTO OUR AREA. NO CHANGES WILL BE NEEDED AT THIS TIME
WITH JUST A SMALL CHANCE OF STORMS ACROSS THE AREA TODAY.
&&
.SHORT TERM...(TODAY THROUGH TUESDAY)
ISSUED AT 348 AM EDT MON JUN 22 2015
UPPER LEVEL RIDGE WILL BUILD EASTWARD INTO THE AREA THROUGH
TUESDAY. WHILE THAT TRANSITION TAKES PLACE...WE WILL REMAIN IN
NORTHWEST FLOW ALOFT THROUGH THE DAY TODAY. A SMALL THUNDERSTORM
COMPLEX OVER SOUTHERN ILLINOIS AND INDIANA HAS DEVELOPED ON A
NARROW BELT OF MORE MOIST 850 MB AIR OVERLAPPING MUCAPE VALUES OF
OVER 1000 J/KG. THE RAP INDICATES THIS BELT OF RICHER/MORE
UNSTABLE AIR WILL SHIFT EASTWARD THROUGH THE MORNING AND CANNOT
RULE OUT THIS COMPLEX OF STORMS HOLDING TOGETHER IN SOME FORM OR
FASHION AND MAKING IT INTO EAST KENTUCKY AFTER DAWN. LATER IN THE
DAY...THE LIKELIHOOD OF SHOWERS/STORMS IS MUCH LESS COMPARED TO
YESTERDAY AS MID LEVEL CAPPING BEGINS TO DEVELOP DURING THE
AFTERNOON WITH THE BUILDING RIDGE GAINING INFLUENCE ON OUR
WEATHER.
THE OVERNIGHT HOURS TONIGHT INTO TUESDAY MORNING SHOULD BE DRY
WITH A STRONG MID LEVEL CAP IN PLACE...BUT A COLD FRONT WILL BE
DROPPING SOUTHEAST INTO THE OHIO VALLEY DURING THE DAY. THIS
SHOULD SPAWN SHOWERS AND STORMS TO OUR NORTH EARLY IN THE DAY.
OUTFLOWS FROM THESE STORMS WILL THEN LIKELY MOVE INTO OUR NORTHERN
COUNTIES LATE IN THE AFTERNOON PROVIDING THE FOCUS FOR CONVECTIVE
DEVELOPMENT ONCE THE CAP BREAKS. FORECAST MODELS INDICATE A VERY
UNSTABLE ATMOSPHERE OVER NORTHERN KENTUCKY WITH SBCAPE OVER 4000
J/KG...SO ANY STORM WILL LIKELY QUICKLY BECOME QUITE STRONG AND
SPC HAS HIGHLIGHTED OUR NORTHERN COUNTIES WITH A SLIGHT RISK.
TEMPERATURES WILL INCH UP A BIT OVER THE NEXT COUPLE OF DAYS WITH
MOST LOCATIONS REACHING THE 90 TO 95 DEGREE RANGE BY TUESDAY. WITH
DEW POINTS REMAINING GENERALLY IN THE 70 T0 75 DEGREE
RANGE...HEAT INDICES WILL CLIMB INTO THE MID TO UPPER 90S TODAY
AND TO AROUND 100 ON TUESDAY.
.LONG TERM...(TUESDAY NIGHT THROUGH SUNDAY)
ISSUED AT 348 AM EDT MON JUN 22 2015
THE FORECAST LONG WAVE PATTERN WILL BEGIN WITH AN UPPER LEVEL RIDGE
GRADUALLY DAMPENING AS IT HEADS EAST ACROSS THE LOWER MISSISSIPPI
VALLEY...THANKS TO PASSING NORTHERN STREAM SHORT WAVE ENERGY. THE
PATTERN WILL THEN AMPLIFY BY THE LATTER HALF OF THE WEEK...WITH
RIDGING BECOMING ESTABLISHED ACROSS THE WESTERN CONUS...WITH
TROUGHING IN THE EAST. DETAILS ON HOW THE AMPLIFICATION EVOLVES WITH
RESPECT TO SURFACE FEATURES REMAINS LOW CONFIDENCE THIS FAR OUT...SO
STUCK CLOSE TO THE BLENDED GUIDANCE.
PLENTY OF HEAT AND HUMIDITY WILL REMAIN IN PLACE ACROSS EASTERN
KENTUCKY THROUGH THURSDAY...WITH HIGHS CLOSE TO THE 90 DEGREE
MARK...AND HEAT INDICES IN THE 95 TO 100 DEGREE RANGE AT TIMES. A
FRONTAL BOUNDARY LINGERING IN THE VICINITY WILL KEEP STORM CHANCES IN
THE FORECAST...WITH LARGER THUNDERSTORM COMPLEXES LIKELY PLAYING A
ROLE AT SOME POINT.
TROUGHING WILL THEN INCREASE ACROSS THE OHIO AND TENNESSEE VALLEYS
FRIDAY THROUGH SUNDAY...ALLOWING FOR MORE SUSTAINED PERIODS OF
UNSETTLED WEATHER. THIS WILL ALSO BE ACCOMPANIED BY COOLER
TEMPERATURES...WITH HIGHS DROPPING BACK INTO THE LOW TO MID 80S WITH
A LITTLE LESS HUMIDITY.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON)
ISSUED AT 217 PM EDT MON JUN 22 2015
VFR CONDITIONS EXPECTED THROUGH THE FORECAST PERIOD. WILL HAVE
SOME ISOLATED THUNDERSTORMS FIRING THIS AFTERNOON...MAINLY IN OUR
SOUTH AND EAST. CAN ALSO EXPECT THE TYPICAL PATCHY VALLEY FOG
THROUGH THE OVERNIGHT. WINDS ARE LIGHT FROM THE WEST...SOUTHWEST
BUT WILL INCREASE TO AROUND 10 KTS BY TOMORROW AS A COLD FRONTAL
BOUNDARY DROPS SOUTHWARD TOWARDS THE OHIO RIVER LATE IN THE DAY.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
UPDATE...RAY
SHORT TERM...ABE
LONG TERM...GEOGERIAN
AVIATION...RAY
AREA FORECAST DISCUSSION
NWS LOUISVILLE KY
120 PM EDT Mon Jun 22 2015
...Updated Aviation Discussion...
...Forecast Update...
Updated at 1155 AM EDT Mon Jun 22 2015
Sent another set of zones out to remove the morning shower wording.
Updated at 850 AM EDT Mon Jun 22 2015
Complex from earlier is fading fast, and have pulled thunder wording
from the rest of the morning. Still do not see any upper level
feature to enhance precip chances today, and latest HRRR is
seemingly the only model handling current feature well. It`s
forecast remains dry the rest of the day as well, so have kept in a
dry afternoon forecast. Once these clouds dissipate, we should warm
to around 90 degrees this afternoon, with heat indices topping out
in the mid to upper 90s. Perhaps a spot or two will touch 100.
Updated at 655 AM EDT Mon Jun 22 2015
The current complex of showers/storms over southern IN/central KY is
weakening and will continue to do so as it moves east into east
central KY. The current forecast handles this well.
Some of the latest high-res models indicates another upper level
shortwave could cause another complex of storms this afternoon.
Will stick with the majority of models giving a dry forecast for now
but it is something to watch as this pattern contains many subtle
waves.
Also will issue an SPS for heat indices maxing out just over 100
degrees each afternoon through Thurs.
.SHORT TERM (Now through Tuesday)...
Updated at 325 AM EDT Mon Jun 22 2015
...Strong Storms Possible Early this Morning...
Water vapor imagery shows a mid level shortwave which was producing
showers/storms over southern IL/southwest IN early this morning.
This wave looks to continue to push ESE through the Ohio Valley
through the morning hours. Mesoanalysis shows minimal CAPE values
over our region except for an area south of an Evansville to E-town
to Lake Cumberland line where elevated mixed layer CAPE values were
running around 500-1500 J/KG. An effective bulk shear axis of 35-40
kts was pointed southeast from Evansville along that same area.
While the upper level shortwave may support the current complex of
storms as it moves ESE along the I-64 corridor, we would expect
perhaps some weakening due to a less favorable environment. The
latest radar trends indicate some southward develop from the ongoing
complex which may become a trend as we go through the morning hours
with the better environment SSE of the current complex. As we saw
yesterday evening, mesoscale boundaries will have the ability to
increase storm strength as they collide with ongoing convection.
Overall feel that storms this morning will remain sub-severe with
wind gusts up to 50 mph and perhaps some small hail. However, can`t
rule out an isld severe storm...a 60 mph gust was measured around 2
am EDT/1 am CDT in Robinson, IL. Also, storms will continue to
produce a lot of lightning and very heavy downpours. If current
timing holds, this complex of storms should be clear of the area by
early afternoon.
For the rest of the afternoon and tonight, upper level ridging
should build into the region enough to result in dry conditions.
High temps should reach the lower 90s as skies become only partly
cloudy this afternoon. Heat indices will max out in the 98-102
range this afternoon. Tonight we won`t see much of a cool down with
the hot, humid airmass staying in place. Expect lows in the low to
mid 70s.
Tuesday a sfc front and upper level shortwave trough will drop south
into the Ohio Valley. With such a warm/moist/unstable airmass ahead
of it, strong to severe storms will be on the table. The main
threats will be damaging winds and large hail in addition to
torrential downpours. Storms should enter southern Indiana by late
morning limiting high temps to the upper 80s. However, low to mid
90s look likely for most of central KY. Heat indices will again top
out in the upper 90s to low 100s Tue afternoon.
.LONG TERM (Tuesday Night through Sunday)...
Issued at 312 AM EDT Mon Jun 22 2015
Upper level ridging will be entrenched across the southern CONUS at
the beginning of the long term period. A cold front moving south
across the area Tuesday will stall out as it runs into this ridging.
Storms will likely be ongoing Tuesday evening. These storms should
gradually weaken into the late evening to overnight hours as daytime
heating wanes. Temperatures on Wednesday will rise into the upper
80s to lower 90s with storms firing up along the washed out boundary
across central Kentucky. Thursday will be more of the same as
temperatures rise into the lower 90s. Heat index values each
afternoon Wednesday and Thursday will peak in the mid 90s to lower
100s. With these heat indices caution should be exercised during the
afternoon hours for those who are outside.
Friday into Friday night should actually see a transition into a bit
cooler pattern. A low pressure system will track northeast across
the lower Ohio Valley Friday night and drag a cold front through on
Saturday. Ahead of the cold front at least a portion of the region
will be in the warm sector on Friday afternoon into Friday night.
Storms will develop Friday and continue overnight as the low moves
through. Though it is fairly far out in the forecast period, it is
possible some of the storms could become strong. In addition, with
precipitable water values around 2 inches, rainfall with the storms
will be moderate to heavy at times. Rain should finally come to an
end by Saturday afternoon/evening, with scattered storms developing
again on Sunday. Temperatures Saturday and Sunday in the wake of the
cold front will be cooler with highs in the low to mid 80s and lows
in the mid to upper 60s.
&&
.AVIATION (18Z TAF Update)...
Updated at 115 PM EDT Mon Jun 22 2015
Have the remains of earlier storms over southern Indiana maintaining
mid-level cloudiness over KLEX this hour. Also have cirrus
streaming in from the north, which looks to be squashing convection
across the area, according to latest visible satellite imagery. Have
put in VCSH for KBWG, but not confident the showers to the west will
survive. Low pressure to our west will keep our winds generally from
the southwest this period.
&&
.LMK WATCHES/WARNINGS/ADVISORIES...
KY...NONE.
IN...NONE.
&&
$$
Updates........RJS/AMS
Short Term.....AMS
Long Term......EER
Aviation.......RJS
AREA FORECAST DISCUSSION
NWS LOUISVILLE KY
1156 AM EDT Mon Jun 22 2015
...Forecast Update...
Updated at 1155 AM EDT Mon Jun 22 2015
Sent another set of zones out to remove the morning shower wording.
Updated at 850 AM EDT Mon Jun 22 2015
Complex from earlier is fading fast, and have pulled thunder wording
from the rest of the morning. Still do not see any upper level
feature to enhance precip chances today, and latest HRRR is
seemingly the only model handling current feature well. It`s
forecast remains dry the rest of the day as well, so have kept in a
dry afternoon forecast. Once these clouds dissipate, we should warm
to around 90 degrees this afternoon, with heat indices topping out
in the mid to upper 90s. Perhaps a spot or two will touch 100.
Updated at 655 AM EDT Mon Jun 22 2015
The current complex of showers/storms over southern IN/central KY is
weakening and will continue to do so as it moves east into east
central KY. The current forecast handles this well.
Some of the latest high-res models indicates another upper level
shortwave could cause another complex of storms this afternoon.
Will stick with the majority of models giving a dry forecast for now
but it is something to watch as this pattern contains many subtle
waves.
Also will issue an SPS for heat indices maxing out just over 100
degrees each afternoon through Thurs.
.SHORT TERM (Now through Tuesday)...
Updated at 325 AM EDT Mon Jun 22 2015
...Strong Storms Possible Early this Morning...
Water vapor imagery shows a mid level shortwave which was producing
showers/storms over southern IL/southwest IN early this morning.
This wave looks to continue to push ESE through the Ohio Valley
through the morning hours. Mesoanalysis shows minimal CAPE values
over our region except for an area south of an Evansville to E-town
to Lake Cumberland line where elevated mixed layer CAPE values were
running around 500-1500 J/KG. An effective bulk shear axis of 35-40
kts was pointed southeast from Evansville along that same area.
While the upper level shortwave may support the current complex of
storms as it moves ESE along the I-64 corridor, we would expect
perhaps some weakening due to a less favorable environment. The
latest radar trends indicate some southward develop from the ongoing
complex which may become a trend as we go through the morning hours
with the better environment SSE of the current complex. As we saw
yesterday evening, mesoscale boundaries will have the ability to
increase storm strength as they collide with ongoing convection.
Overall feel that storms this morning will remain sub-severe with
wind gusts up to 50 mph and perhaps some small hail. However, can`t
rule out an isld severe storm...a 60 mph gust was measured around 2
am EDT/1 am CDT in Robinson, IL. Also, storms will continue to
produce a lot of lightning and very heavy downpours. If current
timing holds, this complex of storms should be clear of the area by
early afternoon.
For the rest of the afternoon and tonight, upper level ridging
should build into the region enough to result in dry conditions.
High temps should reach the lower 90s as skies become only partly
cloudy this afternoon. Heat indices will max out in the 98-102
range this afternoon. Tonight we won`t see much of a cool down with
the hot, humid airmass staying in place. Expect lows in the low to
mid 70s.
Tuesday a sfc front and upper level shortwave trough will drop south
into the Ohio Valley. With such a warm/moist/unstable airmass ahead
of it, strong to severe storms will be on the table. The main
threats will be damaging winds and large hail in addition to
torrential downpours. Storms should enter southern Indiana by late
morning limiting high temps to the upper 80s. However, low to mid
90s look likely for most of central KY. Heat indices will again top
out in the upper 90s to low 100s Tue afternoon.
.LONG TERM (Tuesday Night through Sunday)...
Issued at 312 AM EDT Mon Jun 22 2015
Upper level ridging will be entrenched across the southern CONUS at
the beginning of the long term period. A cold front moving south
across the area Tuesday will stall out as it runs into this ridging.
Storms will likely be ongoing Tuesday evening. These storms should
gradually weaken into the late evening to overnight hours as daytime
heating wanes. Temperatures on Wednesday will rise into the upper
80s to lower 90s with storms firing up along the washed out boundary
across central Kentucky. Thursday will be more of the same as
temperatures rise into the lower 90s. Heat index values each
afternoon Wednesday and Thursday will peak in the mid 90s to lower
100s. With these heat indices caution should be exercised during the
afternoon hours for those who are outside.
Friday into Friday night should actually see a transition into a bit
cooler pattern. A low pressure system will track northeast across
the lower Ohio Valley Friday night and drag a cold front through on
Saturday. Ahead of the cold front at least a portion of the region
will be in the warm sector on Friday afternoon into Friday night.
Storms will develop Friday and continue overnight as the low moves
through. Though it is fairly far out in the forecast period, it is
possible some of the storms could become strong. In addition, with
precipitable water values around 2 inches, rainfall with the storms
will be moderate to heavy at times. Rain should finally come to an
end by Saturday afternoon/evening, with scattered storms developing
again on Sunday. Temperatures Saturday and Sunday in the wake of the
cold front will be cooler with highs in the low to mid 80s and lows
in the mid to upper 60s.
&&
.AVIATION (12Z TAF Update)...
Updated at 645 AM EDT Mon Jun 22 2015
A complex of showers/storms was decreasing in strength this morning
as it crosses I-65. Expect another hr or so of showers with
embedded t-storms at SDF likely not causing any restrictions or
perhaps just brief MVFR. VCSH will be possible at LEX between
12-14Z, but the complex will likely diminish almost completely
before reaching LEX. The rest of the TAF period is VFR. Some
models indicate we could see additional showers/storms today if we
can get a shortwave to kick off convection. However, confidence is
very low at this time with most models remaining dry so will leave
the TAFs dry.
SSW winds will be gusty this afternoon outside of any convection
with gusts up to 20 kts possible.
&&
.LMK WATCHES/WARNINGS/ADVISORIES...
KY...NONE.
IN...NONE.
&&
$$
Updates........RJS/AMS
Short Term.....AMS
Long Term......EER
Aviation.......AMS
AREA FORECAST DISCUSSION
NWS JACKSON KY
1130 AM EDT MON JUN 22 2015
.UPDATE...
ISSUED AT 1130 AM EDT MON JUN 22 2015
UPDATED GRIDS THIS MORNING FOR MOST RECENT HOURLY OBS. ALSO
FRESHENED UP ZONE WORDING AND REMOVED FOG. LITTLE IF ANYTHING
LEFT IN OUR AREA TO INDICATE STORM COMPLEXES ROLLED THROUGH CNTRL
KY LAST NIGHT INTO EARLY THIS MORNING. THE HRRR HINTS AT SOME
REGENERATION OF STORMS ACROSS OUR AREA THIS AFTERNOON ALONG WHAT
MAY BE A WEAK SFC CONVECTIVE BOUNDARY FROM LAST NIGHTS ACTIVITY.
BUT OTHER MODELS HAVE DISCOUNTED THIS POSSIBILITY. ELONGATED RIDGE
FROM THE WEST DOES BEGIN AN ATTEMPT AT NOSING ITS WAY BACK INTO
OUR AREA TODAY WHICH COULD EXPLAIN THE DISCONTINUITY IN NEAR TERM
SOLUTIONS. WILL HAVE TO MONITOR TO SEE IF ANYTHING CAN FIRE. FOR
NOW WENT WITH AN OPTIMISTIC ISOLD POPS FOR THE REMAINDER OF THE
DAY.
UPDATE ISSUED AT 705 AM EDT MON JUN 22 2015
UPSTREAM THUNDERSTORM COMPLEX IS WEAKENING FAST AND PROBABLY WILL
NOT MAKE IT INTO OUR AREA. NO CHANGES WILL BE NEEDED AT THIS TIME
WITH JUST A SMALL CHANCE OF STORMS ACROSS THE AREA TODAY.
&&
.SHORT TERM...(TODAY THROUGH TUESDAY)
ISSUED AT 348 AM EDT MON JUN 22 2015
UPPER LEVEL RIDGE WILL BUILD EASTWARD INTO THE AREA THROUGH
TUESDAY. WHILE THAT TRANSITION TAKES PLACE...WE WILL REMAIN IN
NORTHWEST FLOW ALOFT THROUGH THE DAY TODAY. A SMALL THUNDERSTORM
COMPLEX OVER SOUTHERN ILLINOIS AND INDIANA HAS DEVELOPED ON A
NARROW BELT OF MORE MOIST 850 MB AIR OVERLAPPING MUCAPE VALUES OF
OVER 1000 J/KG. THE RAP INDICATES THIS BELT OF RICHER/MORE
UNSTABLE AIR WILL SHIFT EASTWARD THROUGH THE MORNING AND CANNOT
RULE OUT THIS COMPLEX OF STORMS HOLDING TOGETHER IN SOME FORM OR
FASHION AND MAKING IT INTO EAST KENTUCKY AFTER DAWN. LATER IN THE
DAY...THE LIKELIHOOD OF SHOWERS/STORMS IS MUCH LESS COMPARED TO
YESTERDAY AS MID LEVEL CAPPING BEGINS TO DEVELOP DURING THE
AFTERNOON WITH THE BUILDING RIDGE GAINING INFLUENCE ON OUR
WEATHER.
THE OVERNIGHT HOURS TONIGHT INTO TUESDAY MORNING SHOULD BE DRY
WITH A STRONG MID LEVEL CAP IN PLACE...BUT A COLD FRONT WILL BE
DROPPING SOUTHEAST INTO THE OHIO VALLEY DURING THE DAY. THIS
SHOULD SPAWN SHOWERS AND STORMS TO OUR NORTH EARLY IN THE DAY.
OUTFLOWS FROM THESE STORMS WILL THEN LIKELY MOVE INTO OUR NORTHERN
COUNTIES LATE IN THE AFTERNOON PROVIDING THE FOCUS FOR CONVECTIVE
DEVELOPMENT ONCE THE CAP BREAKS. FORECAST MODELS INDICATE A VERY
UNSTABLE ATMOSPHERE OVER NORTHERN KENTUCKY WITH SBCAPE OVER 4000
J/KG...SO ANY STORM WILL LIKELY QUICKLY BECOME QUITE STRONG AND
SPC HAS HIGHLIGHTED OUR NORTHERN COUNTIES WITH A SLIGHT RISK.
TEMPERATURES WILL INCH UP A BIT OVER THE NEXT COUPLE OF DAYS WITH
MOST LOCATIONS REACHING THE 90 TO 95 DEGREE RANGE BY TUESDAY. WITH
DEWPOINTS REMAINING GENERALLY IN THE 70 T0 75 DEGREE RANGE...HEAT
INDICES WILL CLIMB INTO THE MID TO UPPER 90S TODAY AND TO AROUND
100 ON TUESDAY.
.LONG TERM...(TUESDAY NIGHT THROUGH SUNDAY)
ISSUED AT 348 AM EDT MON JUN 22 2015
THE FORECAST LONG WAVE PATTERN WILL BEGIN WITH AN UPPER LEVEL RIDGE
GRADUALLY DAMPENING AS IT HEADS EAST ACROSS THE LOWER MISSISSIPPI
VALLEY...THANKS TO PASSING NORTHERN STREAM SHORT WAVE ENERGY. THE
PATTERN WILL THEN AMPLIFY BY THE LATTER HALF OF THE WEEK...WITH
RIDGING BECOMING ESTABLISHED ACROSS THE WESTERN CONUS...WITH
TROUGHING IN THE EAST. DETAILS ON HOW THE AMPLIFICATION EVOLVES WITH
RESPECT TO SURFACE FEATURES REMAINS LOW CONFIDENCE THIS FAR OUT...SO
STUCK CLOSE TO THE BLENDED GUIDANCE.
PLENTY OF HEAT AND HUMIDITY WILL REMAIN IN PLACE ACROSS EASTERN
KENTUCKY THROUGH THURSDAY...WITH HIGHS CLOSE TO THE 90 DEGREE
MARK...AND HEAT INDICES IN THE 95 TO 100 DEGREE RANGE AT TIMES. A
FRONTAL BOUNDARY LINGERING IN THE VICINITY WILL KEEP STORM CHANCES IN
THE FORECAST...WITH LARGER THUNDERSTORM COMPLEXES LIKELY PLAYING A
ROLE AT SOME POINT.
TROUGHING WILL THEN INCREASE ACROSS THE OHIO AND TENNESSEE VALLEYS
FRIDAY THROUGH SUNDAY...ALLOWING FOR MORE SUSTAINED PERIODS OF
UNSETTLED WEATHER. THIS WILL ALSO BE ACCOMPANIED BY COOLER
TEMPERATURES...WITH HIGHS DROPPING BACK INTO THE LOW TO MID 80S WITH
A LITTLE LESS HUMIDITY.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z TUESDAY MORNING)
ISSUED AT 705 AM EDT MON JUN 22 2015
VFR CONDITIONS ARE ANTICIPATED OUTSIDE OF SOME PATCHY MVFR FOG
EARLY. JUST A SMALL CHANCE OF THUNDERSTORMS TODAY. WINDS WILL BE
WEST-SOUTHWEST AND A BIT GUSTY DURING THE AFTERNOON...ESPECIALLY
FOR OUR WESTERN SITES.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
UPDATE...RAY
SHORT TERM...ABE
LONG TERM...GEOGERIAN
AVIATION...ABE
AREA FORECAST DISCUSSION
NWS LOUISVILLE KY
852 AM EDT Mon Jun 22 2015
...Forecast Update...
Updated at 850 AM EDT Mon Jun 22 2015
Complex from earlier is fading fast, and have pulled thunder wording
from the rest of the morning. Still do not see any upper level
feature to enhance precip chances today, and latest HRRR is
seemingly the only model handling current feature well. It`s
forecast remains dry the rest of the day as well, so have kept in a
dry afternoon forecast. Once these clouds dissipate, we should warm
to around 90 degrees this afternoon, with heat indices topping out
in the mid to upper 90s. Perhaps a spot or two will touch 100.
Updated at 655 AM EDT Mon Jun 22 2015
The current complex of showers/storms over southern IN/central KY is
weakening and will continue to do so as it moves east into east
central KY. The current forecast handles this well.
Some of the latest high-res models indicates another upper level
shortwave could cause another complex of storms this afternoon.
Will stick with the majority of models giving a dry forecast for now
but it is something to watch as this pattern contains many subtle
waves.
Also will issue an SPS for heat indices maxing out just over 100
degrees each afternoon through Thurs.
.SHORT TERM (Now through Tuesday)...
Updated at 325 AM EDT Mon Jun 22 2015
...Strong Storms Possible Early this Morning...
Water vapor imagery shows a mid level shortwave which was producing
showers/storms over southern IL/southwest IN early this morning.
This wave looks to continue to push ESE through the Ohio Valley
through the morning hours. Mesoanalysis shows minimal CAPE values
over our region except for an area south of an Evansville to E-town
to Lake Cumberland line where elevated mixed layer CAPE values were
running around 500-1500 J/KG. An effective bulk shear axis of 35-40
kts was pointed southeast from Evansville along that same area.
While the upper level shortwave may support the current complex of
storms as it moves ESE along the I-64 corridor, we would expect
perhaps some weakening due to a less favorable environment. The
latest radar trends indicate some southward develop from the ongoing
complex which may become a trend as we go through the morning hours
with the better environment SSE of the current complex. As we saw
yesterday evening, mesoscale boundaries will have the ability to
increase storm strength as they collide with ongoing convection.
Overall feel that storms this morning will remain sub-severe with
wind gusts up to 50 mph and perhaps some small hail. However, can`t
rule out an isld severe storm...a 60 mph gust was measured around 2
am EDT/1 am CDT in Robinson, IL. Also, storms will continue to
produce a lot of lightning and very heavy downpours. If current
timing holds, this complex of storms should be clear of the area by
early afternoon.
For the rest of the afternoon and tonight, upper level ridging
should build into the region enough to result in dry conditions.
High temps should reach the lower 90s as skies become only partly
cloudy this afternoon. Heat indices will max out in the 98-102
range this afternoon. Tonight we won`t see much of a cool down with
the hot, humid airmass staying in place. Expect lows in the low to
mid 70s.
Tuesday a sfc front and upper level shortwave trough will drop south
into the Ohio Valley. With such a warm/moist/unstable airmass ahead
of it, strong to severe storms will be on the table. The main
threats will be damaging winds and large hail in addition to
torrential downpours. Storms should enter southern Indiana by late
morning limiting high temps to the upper 80s. However, low to mid
90s look likely for most of central KY. Heat indices will again top
out in the upper 90s to low 100s Tue afternoon.
.LONG TERM (Tuesday Night through Sunday)...
Issued at 312 AM EDT Mon Jun 22 2015
Upper level ridging will be entrenched across the southern CONUS at
the beginning of the long term period. A cold front moving south
across the area Tuesday will stall out as it runs into this ridging.
Storms will likely be ongoing Tuesday evening. These storms should
gradually weaken into the late evening to overnight hours as daytime
heating wanes. Temperatures on Wednesday will rise into the upper
80s to lower 90s with storms firing up along the washed out boundary
across central Kentucky. Thursday will be more of the same as
temperatures rise into the lower 90s. Heat index values each
afternoon Wednesday and Thursday will peak in the mid 90s to lower
100s. With these heat indices caution should be exercised during the
afternoon hours for those who are outside.
Friday into Friday night should actually see a transition into a bit
cooler pattern. A low pressure system will track northeast across
the lower Ohio Valley Friday night and drag a cold front through on
Saturday. Ahead of the cold front at least a portion of the region
will be in the warm sector on Friday afternoon into Friday night.
Storms will develop Friday and continue overnight as the low moves
through. Though it is fairly far out in the forecast period, it is
possible some of the storms could become strong. In addition, with
precipitable water values around 2 inches, rainfall with the storms
will be moderate to heavy at times. Rain should finally come to an
end by Saturday afternoon/evening, with scattered storms developing
again on Sunday. Temperatures Saturday and Sunday in the wake of the
cold front will be cooler with highs in the low to mid 80s and lows
in the mid to upper 60s.
&&
.AVIATION (12Z TAF Update)...
Updated at 645 AM EDT Mon Jun 22 2015
A complex of showers/storms was decreasing in strength this morning
as it crosses I-65. Expect another hr or so of showers with
embedded t-storms at SDF likely not causing any restrictions or
perhaps just brief MVFR. VCSH will be possible at LEX between
12-14Z, but the complex will likely diminish almost completely
before reaching LEX. The rest of the TAF period is VFR. Some
models indicate we could see additional showers/storms today if we
can get a shortwave to kick off convection. However, confidence is
very low at this time with most models remaining dry so will leave
the TAFs dry.
SSW winds will be gusty this afternoon outside of any convection
with gusts up to 20 kts possible.
&&
.LMK WATCHES/WARNINGS/ADVISORIES...
KY...NONE.
IN...NONE.
&&
$$
Updates........RJS/AMS
Short Term.....AMS
Long Term......EER
Aviation.......AMS
AREA FORECAST DISCUSSION
NWS JACKSON KY
705 AM EDT MON JUN 22 2015
.UPDATE...
ISSUED AT 705 AM EDT MON JUN 22 2015
UPSTREAM THUNDERSTORM COMPLEX IS WEAKENING FAST AND PROBABLY WILL
NOT MAKE IT INTO OUR AREA. NO CHANGES WILL BE NEEDED AT THIS TIME
WITH JUST A SMALL CHANCE OF STORMS ACROSS THE AREA TODAY.
&&
.SHORT TERM...(TODAY THROUGH TUESDAY)
ISSUED AT 348 AM EDT MON JUN 22 2015
UPPER LEVEL RIDGE WILL BUILD EASTWARD INTO THE AREA THROUGH
TUESDAY. WHILE THAT TRANSITION TAKES PLACE...WE WILL REMAIN IN
NORTHWEST FLOW ALOFT THROUGH THE DAY TODAY. A SMALL THUNDERSTORM
COMPLEX OVER SOUTHERN ILLINOIS AND INDIANA HAS DEVELOPED ON A
NARROW BELT OF MORE MOIST 850 MB AIR OVERLAPPING MUCAPE VALUES OF
OVER 1000 J/KG. THE RAP INDICATES THIS BELT OF RICHER/MORE
UNSTABLE AIR WILL SHIFT EASTWARD THROUGH THE MORNING AND CANNOT
RULE OUT THIS COMPLEX OF STORMS HOLDING TOGETHER IN SOME FORM OR
FASHION AND MAKING IT INTO EAST KENTUCKY AFTER DAWN. LATER IN THE
DAY...THE LIKELIHOOD OF SHOWERS/STORMS IS MUCH LESS COMPARED TO
YESTERDAY AS MID LEVEL CAPPING BEGINS TO DEVELOP DURING THE
AFTERNOON WITH THE BUILDING RIDGE GAINING INFLUENCE ON OUR
WEATHER.
THE OVERNIGHT HOURS TONIGHT INTO TUESDAY MORNING SHOULD BE DRY
WITH A STRONG MID LEVEL CAP IN PLACE...BUT A COLD FRONT WILL BE
DROPPING SOUTHEAST INTO THE OHIO VALLEY DURING THE DAY. THIS
SHOULD SPAWN SHOWERS AND STORMS TO OUR NORTH EARLY IN THE DAY.
OUTFLOWS FROM THESE STORMS WILL THEN LIKELY MOVE INTO OUR NORTHERN
COUNTIES LATE IN THE AFTERNOON PROVIDING THE FOCUS FOR CONVECTIVE
DEVELOPMENT ONCE THE CAP BREAKS. FORECAST MODELS INDICATE A VERY
UNSTABLE ATMOSPHERE OVER NORTHERN KENTUCKY WITH SBCAPE OVER 4000
J/KG...SO ANY STORM WILL LIKELY QUICKLY BECOME QUITE STRONG AND
SPC HAS HIGHLIGHTED OUR NORTHERN COUNTIES WITH A SLIGHT RISK.
TEMPERATURES WILL INCH UP A BIT OVER THE NEXT COUPLE OF DAYS WITH
MOST LOCATIONS REACHING THE 90 TO 95 DEGREE RANGE BY TUESDAY. WITH
DEWPOINTS REMAINING GENERALLY IN THE 70 T0 75 DEGREE RANGE...HEAT
INDICES WILL CLIMB INTO THE MID TO UPPER 90S TODAY AND TO AROUND
100 ON TUESDAY.
.LONG TERM...(TUESDAY NIGHT THROUGH SUNDAY)
ISSUED AT 348 AM EDT MON JUN 22 2015
THE FORECAST LONG WAVE PATTERN WILL BEGIN WITH AN UPPER LEVEL RIDGE
GRADUALLY DAMPENING AS IT HEADS EAST ACROSS THE LOWER MISSISSIPPI
VALLEY...THANKS TO PASSING NORTHERN STREAM SHORT WAVE ENERGY. THE
PATTERN WILL THEN AMPLIFY BY THE LATTER HALF OF THE WEEK...WITH
RIDGING BECOMING ESTABLISHED ACROSS THE WESTERN CONUS...WITH
TROUGHING IN THE EAST. DETAILS ON HOW THE AMPLIFICATION EVOLVES WITH
RESPECT TO SURFACE FEATURES REMAINS LOW CONFIDENCE THIS FAR OUT...SO
STUCK CLOSE TO THE BLENDED GUIDANCE.
PLENTY OF HEAT AND HUMIDITY WILL REMAIN IN PLACE ACROSS EASTERN
KENTUCKY THROUGH THURSDAY...WITH HIGHS CLOSE TO THE 90 DEGREE
MARK...AND HEAT INDICES IN THE 95 TO 100 DEGREE RANGE AT TIMES. A
FRONTAL BOUNDARY LINGERING IN THE VICINITY WILL KEEP STORM CHANCES IN
THE FORECAST...WITH LARGER THUNDERSTORM COMPLEXES LIKELY PLAYING A
ROLE AT SOME POINT.
TROUGHING WILL THEN INCREASE ACROSS THE OHIO AND TENNESSEE VALLEYS
FRIDAY THROUGH SUNDAY...ALLOWING FOR MORE SUSTAINED PERIODS OF
UNSETTLED WEATHER. THIS WILL ALSO BE ACCOMPANIED BY COOLER
TEMPERATURES...WITH HIGHS DROPPING BACK INTO THE LOW TO MID 80S WITH
A LITTLE LESS HUMIDITY.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z TUESDAY MORNING)
ISSUED AT 705 AM EDT MON JUN 22 2015
VFR CONDITIONS ARE ANTICIPATED OUTSIDE OF SOME PATCHY MVFR FOG
EARLY. JUST A SMALL CHANCE OF THUNDERSTORMS TODAY. WINDS WILL BE
WEST-SOUTHWEST AND A BIT GUSTY DURING THE AFTERNOON...ESPECIALLY
FOR OUR WESTERN SITES.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...ABE
SHORT TERM...ABE
LONG TERM...GEOGERIAN
AVIATION...ABE
AREA FORECAST DISCUSSION
NWS JACKSON KY
348 AM EDT MON JUN 22 2015
.SHORT TERM...(TODAY THROUGH TUESDAY)
ISSUED AT 348 AM EDT MON JUN 22 2015
UPPER LEVEL RIDGE WILL BUILD EASTWARD INTO THE AREA THROUGH
TUESDAY. WHILE THAT TRANSITION TAKES PLACE...WE WILL REMAIN IN
NORTHWEST FLOW ALOFT THROUGH THE DAY TODAY. A SMALL THUNDERSTORM
COMPLEX OVER SOUTHERN ILLINOIS AND INDIANA HAS DEVELOPED ON A
NARROW BELT OF MORE MOIST 850 MB AIR OVERLAPPING MUCAPE VALUES OF
OVER 1000 J/KG. THE RAP INDICATES THIS BELT OF RICHER/MORE
UNSTABLE AIR WILL SHIFT EASTWARD THROUGH THE MORNING AND CANNOT
RULE OUT THIS COMPLEX OF STORMS HOLDING TOGETHER IN SOME FORM OR
FASHION AND MAKING IT INTO EAST KENTUCKY AFTER DAWN. LATER IN THE
DAY...THE LIKELIHOOD OF SHOWERS/STORMS IS MUCH LESS COMPARED TO
YESTERDAY AS MID LEVEL CAPPING BEGINS TO DEVELOP DURING THE
AFTERNOON WITH THE BUILDING RIDGE GAINING INFLUENCE ON OUR
WEATHER.
THE OVERNIGHT HOURS TONIGHT INTO TUESDAY MORNING SHOULD BE DRY
WITH A STRONG MID LEVEL CAP IN PLACE...BUT A COLD FRONT WILL BE
DROPPING SOUTHEAST INTO THE OHIO VALLEY DURING THE DAY. THIS
SHOULD SPAWN SHOWERS AND STORMS TO OUR NORTH EARLY IN THE DAY.
OUTFLOWS FROM THESE STORMS WILL THEN LIKELY MOVE INTO OUR NORTHERN
COUNTIES LATE IN THE AFTERNOON PROVIDING THE FOCUS FOR CONVECTIVE
DEVELOPMENT ONCE THE CAP BREAKS. FORECAST MODELS INDICATE A VERY
UNSTABLE ATMOSPHERE OVER NORTHERN KENTUCKY WITH SBCAPE OVER 4000
J/KG...SO ANY STORM WILL LIKELY QUICKLY BECOME QUITE STRONG AND
SPC HAS HIGHLIGHTED OUR NORTHERN COUNTIES WITH A SLIGHT RISK.
TEMPERATURES WILL INCH UP A BIT OVER THE NEXT COUPLE OF DAYS WITH
MOST LOCATIONS REACHING THE 90 TO 95 DEGREE RANGE BY TUESDAY. WITH
DEWPOINTS REMAINING GENERALLY IN THE 70 T0 75 DEGREE RANGE...HEAT
INDICES WILL CLIMB INTO THE MID TO UPPER 90S TODAY AND TO AROUND
100 ON TUESDAY.
.LONG TERM...(TUESDAY NIGHT THROUGH SUNDAY)
ISSUED AT 348 AM EDT MON JUN 22 2015
THE FORECAST LONG WAVE PATTERN WILL BEGIN WITH AN UPPER LEVEL RIDGE
GRADUALLY DAMPENING AS IT HEADS EAST ACROSS THE LOWER MISSISSIPPI
VALLEY...THANKS TO PASSING NORTHERN STREAM SHORT WAVE ENERGY. THE
PATTERN WILL THEN AMPLIFY BY THE LATTER HALF OF THE WEEK...WITH
RIDGING BECOMING ESTABLISHED ACROSS THE WESTERN CONUS...WITH
TROUGHING IN THE EAST. DETAILS ON HOW THE AMPLIFICATION EVOLVES WITH
RESPECT TO SURFACE FEATURES REMAINS LOW CONFIDENCE THIS FAR OUT...SO
STUCK CLOSE TO THE BLENDED GUIDANCE.
PLENTY OF HEAT AND HUMIDITY WILL REMAIN IN PLACE ACROSS EASTERN
KENTUCKY THROUGH THURSDAY...WITH HIGHS CLOSE TO THE 90 DEGREE
MARK...AND HEAT INDICES IN THE 95 TO 100 DEGREE RANGE AT TIMES. A
FRONTAL BOUNDARY LINGERING IN THE VICINITY WILL KEEP STORM CHANCES IN
THE FORECAST...WITH LARGER THUNDERSTORM COMPLEXES LIKELY PLAYING A
ROLE AT SOME POINT.
TROUGHING WILL THEN INCREASE ACROSS THE OHIO AND TENNESSEE VALLEYS
FRIDAY THROUGH SUNDAY...ALLOWING FOR MORE SUSTAINED PERIODS OF
UNSETTLED WEATHER. THIS WILL ALSO BE ACCOMPANIED BY COOLER
TEMPERATURES...WITH HIGHS DROPPING BACK INTO THE LOW TO MID 80S WITH
A LITTLE LESS HUMIDITY.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT)
ISSUED AT 122 AM EDT MON JUN 22 2015
THUNDERSTORM COMPLEX DROPPING INTO LAKE CUMBERLAND REGION WILL
DIRECTLY IMPACT SME OVER THE NEXT HOUR OR TWO...AND INDIRECTLY
AFFECT REMAINING TAF SITES AS DEBRIS CLOUDS COMPLICATES POTENTIAL
FOG DEVELOPMENT. DUE TO THIS BLANKET OF MID/HIGH LEVEL CLOUDS...I
BACKED OFF ON FOG EXPECTATIONS IN THIS ROUND OF TAFS. OTHERWISE...
VFR CONDITIONS ARE ANTICIPATED ON MONDAY WITH ONLY ISOLATED
THUNDERSTORMS EXPECTED TO DEVELOP DURING THE AFTERNOON. WINDS WILL
BE LIGHT AND GENERALLY FROM THE WEST-SOUTHWEST.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...ABE
LONG TERM...GEOGERIAN
AVIATION...ABE
AREA FORECAST DISCUSSION
NWS LOUISVILLE KY
134 AM EDT Mon Jun 22 2015
...Updated Aviation Discussion...
...Forecast Update...
Updated at 1205 AM EDT Mon Jun 22 2015
After much deliberation and helpful collaboration with PAH and WHAS,
have decided to up PoPs slightly for the overnight hours into the
40% range across southern Indiana and north central Kentucky. The
reason is that convection is currently refiring over southern
Illinois and sliding to the ESE. The NSSL-WRF is about the only
model that shows this (and shows it rather well, actually), with
some slight support from the SPC SREF. The NSSL-WRF brings the
showers and storms right across southwest Indiana and north central
Kentucky, roughly along the I-64 corridor. These overnight storms
are expected to remain slightly elevated and severe weather is not
expected. Having said that, though, the storms over the past several
hours have been impressive lightning producers, and that may
continue into the overnight. Sub-severe gusty winds and pea size
hail aren`t entirely out of the question overnight, especially west
of Louisville.
Updated at 752 PM EDT Sun Jun 21 2015
After chatting with SPC, will allow the Severe Thunderstorm Watch to
expire on time as instability lessens and CIN increases. Will need
to hold on to scattered PoPs for the remainder of the evening hours
however with some weak low level jetting from Missouri to central
Illinois, the entrance region of a small upper jetlet crossing
central Indiana, and a weak 5H wave approaching from the west.
Could see some patchy fog late but there should be enough cirrus
overhead to keep it from becoming too widespread or dense.
.SHORT TERM (Now through Monday Night)...
Updated at 244 PM EDT Sun Jun 21 2015
...Strong to Severe Storms Possible Late This Afternoon into This
Evening...
The synoptic pattern early this afternoon features an expansive
ridge building in across the southern CONUS, whose reach extends up
into portions of southern KY. Further north, an active northern
stream continues to send generally subtle PV anomalies through the
flow, each of which continue to set off clusters of convection.
The forecast for late this afternoon into this evening remains a
rather difficult one, as there are many subtle features to contend
with. Have fairly high confidence that any thunderstorm activity
late this afternoon will be focused across central and southern KY.
KLVX showed a nice boundary push through earlier this afternoon, and
SPC mesoanalysis shows strong moisture convergence along it. The
latest satellite loop confirms this, as a line of cumulus has now
formed along the boundary. Along and south of this boundary is
where the best coverage of storms will be this afternoon.
Forecast soundings still suggest there will be a cap to contend with
across central/southern KY which may help limit updraft intensity to
some extent. However, MLCAPEs in this area have risen to 3000-4000
J/kg according to the latest mesoanalysis data (though this may be a
bit overdone). This strong instability coupled with 20 to 30 knots
of effective shear may lead to some loose storm organization. The
high DCAPE environment suggest localized damaging wind gusts will be
the main threat, although some quarter-sized hail will be possible
as well given the strong instability in place.
That activity should sag south by early this evening, as attention
then shifts to the current convection ongoing over MO. The CAMs are
really struggling with what will happen with this activity through
the rest of the afternoon into this evening, as some want to keep it
mainly elevated and fade it this evening, while others develop it
into a severe linear MCS and plow it southeast into our region
tonight around/after 00Z. The area downstream of this activity over
IL has been slow to destabilize given a thick cirrus shield in place
through much of the day, but that cirrus has now mostly dissipated.
Dprog/dt of the typically reliable HRRR shows a very inconsistent
solution, so confidence is low. Will go with a rather conservative
approach to pops and keep them around 40 percent for the potential
of this activity getting in here later tonight. If it does develop
a cold pool and begin to bow out, then it could bring some severe
wind gusts into portions of southern IN and KY later this evening,
mainly west of I-65. Once this moves through, the rest of the
overnight period will be mainly dry as upper-level ridging builds
overhead.
The ridge will really take hold Monday into Monday night, bringing
mostly dry and hot conditions. Can`t completely rule out a stray
storm Monday afternoon, but forcing mechanisms are lacking and the
mid-level cap will be strong. Therefore, will go with a dry
forecast. Highs will be in the low to mid 90s, with heat indices in
excess of 100 degrees at times. Overnight lows on Monday will be
quite muggy out ahead of another system slated to push through on
Tuesday, with readings only dropping into the mid and upper 70s.
.LONG TERM (Tuesday through Sunday)...
Issued at 220 PM EDT Sun Jun 21 2015
Models have not changed much in their overall pattern, with a ridge
near but centered just southwest of the region early on and then
transition to a more dominant western ridge by the end of the work
week, with troughing over us. That should mean hot days at first
and a little cooler by the end of the work week, but with rain
chances pretty much every day.
&&
.AVIATION (06Z TAF Update)...
Updated at 130 AM EDT Mon Jun 22 2015
The latest high res models indicate that the shower/storms over
south central IL will slowly move ESE toward along the I-64 corridor
later this morning. If this complex holds together as current
models suggest, it would impact SDF between 11-15Z and LEX between
15-18Z. Therefore did include a VCTS group for SDF/LEX later this
morning. BWG should stay clear of additional convection attm.
However, BWG could see some brief light MVFR fog during the pre-dawn
hours. Overall the TAFs are mostly VFR but each TAF site could see
brief periods of flight restrictions based on the above reasons.
Winds will become mostly SSW during the pre-dawn hours remaining
between 5-10 kts. SW winds will be gusty this afternoon outside of
any convection with gusts up to 20 kts possible.
&&
.LMK WATCHES/WARNINGS/ADVISORIES...
KY...NONE.
IN...NONE.
&&
$$
Update.........13
Short Term.....KJD
Long Term......RJS
Aviation.......AMS
AREA FORECAST DISCUSSION
NWS JACKSON KY
122 AM EDT MON JUN 22 2015
.UPDATE...
ISSUED AT 100 AM EDT MON JUN 22 2015
THUNDERSTORM COMPLEX CONTINUES TO DROP SOUTHEAST INTO THE LAKE
CUMBERLAND REGION. TRENDS SEEN IN CLOUD TOP TEMPS...LIGHTNING...
AND RADAR DATA SUGGEST STORMS ARE WEAKENING...BUT UPPED POPS WEST
OF I-75 TO ACCOUNT FOR THIS ACTIVITY AND SKY COVER TO ACCOUNT FOR
DEBRIS CLOUDS. NO OTHER CHANGES MADE AT THIS TIME.
UPDATE ISSUED AT 1058 PM EDT SUN JUN 21 2015
CONVECTION IS TRACKING SOUTHEAST ACROSS CENTRAL KY BUT HAS
WEAKENED A BIT OVERALL AS IT MOVES INTO MORE STABLE AIR BUT STILL
REMAINS RATHER STRONG FOR LATE EVENING. THERE IS SOME ADDITIONAL
STRAY SHOWERS OVER THE BLUEGRASS REGION. THE NEAR TERM CONVECTIVE
ALLOWING MODELS HAVE NOT BEEN HANDLING THIS CENTRAL KY CONVECTION
ALL THAT WELL THOUGH THE 2Z HRRR SEEMS TO BE MORE REALISTIC
COMPARED TO PREVIOUS RUNS BUT PROBABLY IS A BIT TOO SLOW MOVING IT
SOUTHEAST. AT THIS POINT WE HAVE EXTRAPOLATED THIS CONVECTION
SOUTHEAST TOWARD THE LAKE CUMBERLAND REGION...WITH GRADUALLY
DECREASING POPS AND HELD ONTO AT LEAST A SLIGHT CHANCE POP FOR THE
ENTIRE NIGHT. OTHERWISE...HOURLY TEMPS AND DEWPOINTS HAVE ADJUSTED
BASED ON RECENT OBSERVATIONS.
UPDATE ISSUED AT 752 PM EDT SUN JUN 21 2015
APPEARS THAT MOST OF THE ACTIVE WEATHER TONIGHT WAS SOUTH OF THE
MOUNTAIN PARKWAY. THUNDERSTORMS ARE GRADUALLY DISSIPATING THIS
EVENING. WILL KEEP A CHANCE TO SLIGHT POP THROUGH ABOUT MIDNIGHT
FOR ANY RESIDUAL SHOWERS AND THUNDERSTORMS. HRRR SUGGEST A QUIET
OVERNIGHT THEREAFTER. MAY SEE AN ISOLD SHOWER OR THUNDERSTORM
TOMORROW...BUT BUILDING MID AND UPPER LEVEL RIDGE WILL TEND TO CAP
MOST IF NOT ALL CONVECTION AS THE FRONTAL ZONE THAT HAS BEEN
IN OUR VICINITY TAKES A TEMPORARY JOG NORTHWARD. BEEFED UP FOG
THROUGH THE OVERNIGHT FOR THOSE LOCATIONS THAT SAW THE MOST
PRECIPITATION LATE THIS AFTERNOON AND THIS EVENING. OTHERWISE...
AFTER UPDATING THE FORECAST PACKAGE TO BRING IN LINE WITH LATEST
THOUGHTS AND TRENDS ADJUSTED GRIDS TOWARDS MOST RECENT HOURLY OBS.
&&
.SHORT TERM...(THIS EVENING THROUGH MONDAY NIGHT)
ISSUED AT 442 PM EDT SUN JUN 21 2015
CONVECTION IS FIRING ALONG AN OUTFLOW BOUNDARY THAT SETTLED DOWN
INTO OUR AREA TODAY...PRODUCED BY AN MCS TO OUR NORTHWEST LAST
NIGHT. WITH AMPLE SFC BASED INSTABILITY TO DRAW FROM...STORMS HAVE
BEGUN TO FIRE WITH SOME LIKELY REACHING SEVERE LEVELS. WE HAVE
GOTTEN SOME CALLS OF THE POSSIBILITY OF SOME TREES DOWN IN
SOUTHERN PERRY COUNTY...BUT STILL TRYING TO CONFIRM. SPC HAS
ISSUED A SEVERE THUNDERSTORM WATCH FOR AREAS GENERALLY ALONG AND
SOUTH OF THE MOUNTAIN PARKWAY UNTIL 8 PM EDT THIS EVENING. THIS
ACTIVITY WILL SHIFT SOUTHWARD THROUGH THE LATE AFTERNOON AND EARLY
EVENING HOURS BEFORE DISSIPATING.
ELONGATED RIDGE STRETCHING ACROSS THE SOUTHERN CONUS WILL BUILD
BACK TO THE EAST THROUGH THE SHORT TERM...CONTINUING THE HEAT AND
HUMIDITY THAT WILL DRIVE HEAT INDEX VALUES WELL INTO THE 90S...
AND CLOSE TO 100 OVER THE NEXT COUPLE OF AFTERNOONS. THIS RIDGE
WILL TEND TO KEEP ACTIVE WEATHER FROM CORE WESTERLIES TO OUR NORTH
THROUGH THE SHORT TERM PERIOD AS WELL. A TRUE SUMMERTIME PATTERN
TO WELCOME IN THE BEGINNING OF SUMMER.
.LONG TERM...(TUESDAY THROUGH SUNDAY)
ISSUED AT 318 PM EDT SUN JUN 21 2015
MODELS CONTINUE TO BE IN FAIRLY GOOD AGREEMENT THROUGH NEXT
WEEKEND. UNFORTUNATELY...THE HEAT...HUMIDITY...AND CHANCES FOR
PRECIP ARE EXPECTED TO CONTINUE DURING THIS TIME AS WELL. WE WILL
START OFF WITH A BROAD AREA OF RIDGING ACROSS THE SOUTHERN
CONUS...CONTINUING TO REACH ITS WAY EASTWARD INTO THE OHIO RIVER
VALLEY THROUGH THE DAY WEDNESDAY. MEANWHILE...A STRONG SHORTWAVE
WILL PASS SOUTHWARD ALONG THE GREAT LAKES REGION...CREATING AN AREA
OF PACKED ISOBARS AND STRONG WINDS JUST NORTH OF KENTUCKY. THE WNW
FLOW THAT THIS CREATES WILL ALLOW SEVERAL SMALLER SHORTWAVES TO
TRAVERSE THE REGION THROUGH THE WEEK...BRINGING OFF AND ON CHANCES
OF PRECIP AND POSSIBILITIES FOR LARGER MCS DEVELOPMENT.
BY THURSDAY...THE SHORTWAVE THAT MOVED ACROSS THE GREAT LAKES REGION
WILL BECOME WRAPPED UP IN A STRENGTHENING UPPER LEVEL LOW OVER THE
SOUTHEAST CANADIAN COAST. THIS WILL DEEPEN THE NORTHWEST FLOW ACROSS
THE OHIO RIVER VALLEY...AND PUSH THE RIDGING TO OUR SOUTH BACK
WESTWARD TOWARDS THE SOUTHERN PLAINS...AND EVENTUALLY THE FOUR
CORNER STATES BY THURSDAY NIGHT. KINKS IN THIS NW FLOW /SMALL
SHORTWAVES/ WILL CONTINUE TO SHIFT SE TOWARDS THE OHIO RIVER VALLEY
AS THIS OCCURS...STRENGTHENING AS WE HEAD INTO THE WEEKEND AND THE
LONG TERM MODELS TRY TO PRODUCE ANOTHER STRONG UPPER LEVEL LOW WHICH
WILL LEAD TO A DIGGING TROUGH OVER MUCH OF THE EASTERN CONUS. WHILE
THE EXACT TIMING OF THESE FEATURES IS STILL A BIT OFF THIS FAR OUT
IN THE FORECAST...THE OVERALL PATTERN IS QUITE SIMILAR.
AT THE SURFACE...LOW PRESSURE WILL SET UP BELOW THE CLOSED LOW
MOVING FROM THE GREAT LAKES TO SOUTHEASTERN CANADA. FROM THIS LOW A
FRONTAL BOUNDARY WILL EXTEND WESTWARD...BECOMING CAUGHT AND
ELONGATED IN THE WSW FLOW ACROSS THE OHIO RIVER VALLEY. THIS
BOUNDARY IS EXPECTED TO FLUCTUATE...SHIFTING NORTH AS THE NW FLOW
DEEPENS...AND THEN BACK SOUTHWARD AGAIN AS THE LONGWAVE TROUGH
BEGINS TO DIG FARTHER SOUTH. THE COMBINATION OF THIS BOUNDARY AND
PASSING SHORTWAVES WILL CREATING THE RESULTING PRECIP CHANCES
THROUGH THE WEEK. TEMPERATURES WILL BE WARMEST TUESDAY WITH
SOUTHERLY FLOW STILL IN PLACE JUST AHEAD OF THE DROPPING COLD
FRONT...THEN ARE EXPECTED TO FALL SLIGHTLY AS THE FRONT SHEARS OUT
AND SHIFTS BACK AND FORTH ACROSS THE REGION. IF THE EXTENDED MODELS
HOLD TRUE...THE DIGGING TROUGH LATE IN THE WEEKEND WILL RESULT IN A
SURFACE LOW DEVELOPING JUST NORTH OF THE REGION...AND BRINGING OUR
BEST WIDESPREAD CHANCE FOR PRECIP.
GIVEN THE HOT AND HUMID CONDITIONS IN ADDITION TO THE CLOSE
PROXIMITY OF THE BOUNDARY...EXPECT ANY PRECIP THAT DEVELOPS TO HAVE
SOME THUNDER COMPONENT TO IT AND BE MOST PROMINENT DURING THE
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT)
ISSUED AT 122 AM EDT MON JUN 22 2015
THUNDERSTORM COMPLEX DROPPING INTO LAKE CUMBERLAND REGION WILL
DIRECTLY IMPACT SME OVER THE NEXT HOUR OR TWO...AND INDIRECTLY
AFFECT REMAINING TAF SITES AS DEBRIS CLOUDS COMPLICATES POTENTIAL
FOG DEVELOPMENT. DUE TO THIS BLANKET OF MID/HIGH LEVEL CLOUDS...I
BACKED OFF ON FOG EXPECTATIONS IN THIS ROUND OF TAFS. OTHERWISE...
VFR CONDITIONS ARE ANTICIPATED ON MONDAY WITH ONLY ISOLATED
THUNDERSTORMS EXPECTED TO DEVELOP DURING THE AFTERNOON. WINDS WILL
BE LIGHT AND GENERALLY FROM THE WEST-SOUTHWEST.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...ABE
SHORT TERM...RAY
LONG TERM...JMW
AVIATION...ABE
AREA FORECAST DISCUSSION
NWS JACKSON KY
100 AM EDT MON JUN 22 2015
.UPDATE...
ISSUED AT 100 AM EDT MON JUN 22 2015
THUNDERSTORM COMPLEX CONTINUES TO DROP SOUTHEAST INTO THE LAKE
CUMBERLAND REGION. TRENDS SEEN IN CLOUD TOP TEMPS...LIGHTNING...
AND RADAR DATA SUGGEST STORMS ARE WEAKENING...BUT UPPED POPS WEST
OF I-75 TO ACCOUNT FOR THIS ACTIVITY AND SKY COVER TO ACCOUNT FOR
DEBRIS CLOUDS. NO OTHER CHANGES MADE AT THIS TIME.
UPDATE ISSUED AT 1058 PM EDT SUN JUN 21 2015
CONVECTION IS TRACKING SOUTHEAST ACROSS CENTRAL KY BUT HAS
WEAKENED A BIT OVERALL AS IT MOVES INTO MORE STABLE AIR BUT STILL
REMAINS RATHER STRONG FOR LATE EVENING. THERE IS SOME ADDITIONAL
STRAY SHOWERS OVER THE BLUEGRASS REGION. THE NEAR TERM CONVECTIVE
ALLOWING MODELS HAVE NOT BEEN HANDLING THIS CENTRAL KY CONVECTION
ALL THAT WELL THOUGH THE 2Z HRRR SEEMS TO BE MORE REALISTIC
COMPARED TO PREVIOUS RUNS BUT PROBABLY IS A BIT TOO SLOW MOVING IT
SOUTHEAST. AT THIS POINT WE HAVE EXTRAPOLATED THIS CONVECTION
SOUTHEAST TOWARD THE LAKE CUMBERLAND REGION...WITH GRADUALLY
DECREASING POPS AND HELD ONTO AT LEAST A SLIGHT CHANCE POP FOR THE
ENTIRE NIGHT. OTHERWISE...HOURLY TEMPS AND DEWPOINTS HAVE ADJUSTED
BASED ON RECENT OBSERVATIONS.
UPDATE ISSUED AT 752 PM EDT SUN JUN 21 2015
APPEARS THAT MOST OF THE ACTIVE WEATHER TONIGHT WAS SOUTH OF THE
MOUNTAIN PARKWAY. THUNDERSTORMS ARE GRADUALLY DISSIPATING THIS
EVENING. WILL KEEP A CHANCE TO SLIGHT POP THROUGH ABOUT MIDNIGHT
FOR ANY RESIDUAL SHOWERS AND THUNDERSTORMS. HRRR SUGGEST A QUIET
OVERNIGHT THEREAFTER. MAY SEE AN ISOLD SHOWER OR THUNDERSTORM
TOMORROW...BUT BUILDING MID AND UPPER LEVEL RIDGE WILL TEND TO CAP
MOST IF NOT ALL CONVECTION AS THE FRONTAL ZONE THAT HAS BEEN
IN OUR VICINITY TAKES A TEMPORARY JOG NORTHWARD. BEEFED UP FOG
THROUGH THE OVERNIGHT FOR THOSE LOCATIONS THAT SAW THE MOST
PRECIPITATION LATE THIS AFTERNOON AND THIS EVENING. OTHERWISE...
AFTER UPDATING THE FORECAST PACKAGE TO BRING IN LINE WITH LATEST
THOUGHTS AND TRENDS ADJUSTED GRIDS TOWARDS MOST RECENT HOURLY OBS.
&&
.SHORT TERM...(THIS EVENING THROUGH MONDAY NIGHT)
ISSUED AT 442 PM EDT SUN JUN 21 2015
CONVECTION IS FIRING ALONG AN OUTFLOW BOUNDARY THAT SETTLED DOWN
INTO OUR AREA TODAY...PRODUCED BY AN MCS TO OUR NORTHWEST LAST
NIGHT. WITH AMPLE SFC BASED INSTABILITY TO DRAW FROM...STORMS HAVE
BEGUN TO FIRE WITH SOME LIKELY REACHING SEVERE LEVELS. WE HAVE
GOTTEN SOME CALLS OF THE POSSIBILITY OF SOME TREES DOWN IN
SOUTHERN PERRY COUNTY...BUT STILL TRYING TO CONFIRM. SPC HAS
ISSUED A SEVERE THUNDERSTORM WATCH FOR AREAS GENERALLY ALONG AND
SOUTH OF THE MOUNTAIN PARKWAY UNTIL 8 PM EDT THIS EVENING. THIS
ACTIVITY WILL SHIFT SOUTHWARD THROUGH THE LATE AFTERNOON AND EARLY
EVENING HOURS BEFORE DISSIPATING.
ELONGATED RIDGE STRETCHING ACROSS THE SOUTHERN CONUS WILL BUILD
BACK TO THE EAST THROUGH THE SHORT TERM...CONTINUING THE HEAT AND
HUMIDITY THAT WILL DRIVE HEAT INDEX VALUES WELL INTO THE 90S...
AND CLOSE TO 100 OVER THE NEXT COUPLE OF AFTERNOONS. THIS RIDGE
WILL TEND TO KEEP ACTIVE WEATHER FROM CORE WESTERLIES TO OUR NORTH
THROUGH THE SHORT TERM PERIOD AS WELL. A TRUE SUMMERTIME PATTERN
TO WELCOME IN THE BEGINNING OF SUMMER.
.LONG TERM...(TUESDAY THROUGH SUNDAY)
ISSUED AT 318 PM EDT SUN JUN 21 2015
MODELS CONTINUE TO BE IN FAIRLY GOOD AGREEMENT THROUGH NEXT
WEEKEND. UNFORTUNATELY...THE HEAT...HUMIDITY...AND CHANCES FOR
PRECIP ARE EXPECTED TO CONTINUE DURING THIS TIME AS WELL. WE WILL
START OFF WITH A BROAD AREA OF RIDGING ACROSS THE SOUTHERN
CONUS...CONTINUING TO REACH ITS WAY EASTWARD INTO THE OHIO RIVER
VALLEY THROUGH THE DAY WEDNESDAY. MEANWHILE...A STRONG SHORTWAVE
WILL PASS SOUTHWARD ALONG THE GREAT LAKES REGION...CREATING AN AREA
OF PACKED ISOBARS AND STRONG WINDS JUST NORTH OF KENTUCKY. THE WNW
FLOW THAT THIS CREATES WILL ALLOW SEVERAL SMALLER SHORTWAVES TO
TRAVERSE THE REGION THROUGH THE WEEK...BRINGING OFF AND ON CHANCES
OF PRECIP AND POSSIBILITIES FOR LARGER MCS DEVELOPMENT.
BY THURSDAY...THE SHORTWAVE THAT MOVED ACROSS THE GREAT LAKES REGION
WILL BECOME WRAPPED UP IN A STRENGTHENING UPPER LEVEL LOW OVER THE
SOUTHEAST CANADIAN COAST. THIS WILL DEEPEN THE NORTHWEST FLOW ACROSS
THE OHIO RIVER VALLEY...AND PUSH THE RIDGING TO OUR SOUTH BACK
WESTWARD TOWARDS THE SOUTHERN PLAINS...AND EVENTUALLY THE FOUR
CORNER STATES BY THURSDAY NIGHT. KINKS IN THIS NW FLOW /SMALL
SHORTWAVES/ WILL CONTINUE TO SHIFT SE TOWARDS THE OHIO RIVER VALLEY
AS THIS OCCURS...STRENGTHENING AS WE HEAD INTO THE WEEKEND AND THE
LONG TERM MODELS TRY TO PRODUCE ANOTHER STRONG UPPER LEVEL LOW WHICH
WILL LEAD TO A DIGGING TROUGH OVER MUCH OF THE EASTERN CONUS. WHILE
THE EXACT TIMING OF THESE FEATURES IS STILL A BIT OFF THIS FAR OUT
IN THE FORECAST...THE OVERALL PATTERN IS QUITE SIMILAR.
AT THE SURFACE...LOW PRESSURE WILL SET UP BELOW THE CLOSED LOW
MOVING FROM THE GREAT LAKES TO SOUTHEASTERN CANADA. FROM THIS LOW A
FRONTAL BOUNDARY WILL EXTEND WESTWARD...BECOMING CAUGHT AND
ELONGATED IN THE WSW FLOW ACROSS THE OHIO RIVER VALLEY. THIS
BOUNDARY IS EXPECTED TO FLUCTUATE...SHIFTING NORTH AS THE NW FLOW
DEEPENS...AND THEN BACK SOUTHWARD AGAIN AS THE LONGWAVE TROUGH
BEGINS TO DIG FARTHER SOUTH. THE COMBINATION OF THIS BOUNDARY AND
PASSING SHORTWAVES WILL CREATING THE RESULTING PRECIP CHANCES
THROUGH THE WEEK. TEMPERATURES WILL BE WARMEST TUESDAY WITH
SOUTHERLY FLOW STILL IN PLACE JUST AHEAD OF THE DROPPING COLD
FRONT...THEN ARE EXPECTED TO FALL SLIGHTLY AS THE FRONT SHEARS OUT
AND SHIFTS BACK AND FORTH ACROSS THE REGION. IF THE EXTENDED MODELS
HOLD TRUE...THE DIGGING TROUGH LATE IN THE WEEKEND WILL RESULT IN A
SURFACE LOW DEVELOPING JUST NORTH OF THE REGION...AND BRINGING OUR
BEST WIDESPREAD CHANCE FOR PRECIP.
GIVEN THE HOT AND HUMID CONDITIONS IN ADDITION TO THE CLOSE
PROXIMITY OF THE BOUNDARY...EXPECT ANY PRECIP THAT DEVELOPS TO HAVE
SOME THUNDER COMPONENT TO IT AND BE MOST PROMINENT DURING THE
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z MONDAY EVENING)
ISSUED AT 752 PM EDT SUN JUN 21 2015
STORMS IN THE SOUTH...AFFECTING KLOZ AND KSME ARE GRADUALLY
DISSIPATING. VERY MOIST BOUNDARY LAYER AND RECENT PRECIPITATION
WILL LEAD TO SOME PATCHY DENSE FOG IN PLACES...A LITTLE MORE
WIDESPREAD IN AREAS THAT SAW RAIN LATE THIS AFTERNOON AND THIS
EVENING. CONSEQUENTLY HIT OUR SOUTHERN TERMINALS A BIT HARDER
WITH FOG THAN THE NORTHERN SITES. CONDITIONS IMPROVE TOMORROW
MORNING AS DIURNAL HEATING BURNS OFF MOST FOG BY MID MORNING.
OTHERWISE LOOKING AT LIGHT AND VARIABLE WINDS...INCREASING FROM
THE SOUTHWEST AT AROUND 5KT MONDAY.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...ABE
SHORT TERM...RAY
LONG TERM...JMW
AVIATION...RAY
AREA FORECAST DISCUSSION
NWS LOUISVILLE KY
1206 AM EDT Mon Jun 22 2015
...Forecast Update...
Updated at 1205 AM EDT Mon Jun 22 2015
After much deliberation and helpful collaboration with PAH and WHAS,
have decided to up PoPs slightly for the overnight hours into the
40% range across southern Indiana and north central Kentucky. The
reason is that convection is currently refiring over southern
Illinois and sliding to the ESE. The NSSL-WRF is about the only
model that shows this (and shows it rather well, actually), with
some slight support from the SPC SREF. The NSSL-WRF brings the
showers and storms right across southwest Indiana and north central
Kentucky, roughly along the I-64 corridor. These overnight storms
are expected to remain slightly elevated and severe weather is not
expected. Having said that, though, the storms over the past several
hours have been impressive lightning producers, and that may
continue into the overnight. Sub-severe gusty winds and pea size
hail aren`t entirely out of the question overnight, especially west
of Louisville.
Updated at 752 PM EDT Sun Jun 21 2015
After chatting with SPC, will allow the Severe Thunderstorm Watch to
expire on time as instability lessens and CIN increases. Will need
to hold on to scattered PoPs for the remainder of the evening hours
however with some weak low level jetting from Missouri to central
Illinois, the entrance region of a small upper jetlet crossing
central Indiana, and a weak 5H wave approaching from the west.
Could see some patchy fog late but there should be enough cirrus
overhead to keep it from becoming too widespread or dense.
.SHORT TERM (Now through Monday Night)...
Updated at 244 PM EDT Sun Jun 21 2015
...Strong to Severe Storms Possible Late This Afternoon into This
Evening...
The synoptic pattern early this afternoon features an expansive
ridge building in across the southern CONUS, whose reach extends up
into portions of southern KY. Further north, an active northern
stream continues to send generally subtle PV anomalies through the
flow, each of which continue to set off clusters of convection.
The forecast for late this afternoon into this evening remains a
rather difficult one, as there are many subtle features to contend
with. Have fairly high confidence that any thunderstorm activity
late this afternoon will be focused across central and southern KY.
KLVX showed a nice boundary push through earlier this afternoon, and
SPC mesoanalysis shows strong moisture convergence along it. The
latest satellite loop confirms this, as a line of cumulus has now
formed along the boundary. Along and south of this boundary is
where the best coverage of storms will be this afternoon.
Forecast soundings still suggest there will be a cap to contend with
across central/southern KY which may help limit updraft intensity to
some extent. However, MLCAPEs in this area have risen to 3000-4000
J/kg according to the latest mesoanalysis data (though this may be a
bit overdone). This strong instability coupled with 20 to 30 knots
of effective shear may lead to some loose storm organization. The
high DCAPE environment suggest localized damaging wind gusts will be
the main threat, although some quarter-sized hail will be possible
as well given the strong instability in place.
That activity should sag south by early this evening, as attention
then shifts to the current convection ongoing over MO. The CAMs are
really struggling with what will happen with this activity through
the rest of the afternoon into this evening, as some want to keep it
mainly elevated and fade it this evening, while others develop it
into a severe linear MCS and plow it southeast into our region
tonight around/after 00Z. The area downstream of this activity over
IL has been slow to destabilize given a thick cirrus shield in place
through much of the day, but that cirrus has now mostly dissipated.
Dprog/dt of the typically reliable HRRR shows a very inconsistent
solution, so confidence is low. Will go with a rather conservative
approach to pops and keep them around 40 percent for the potential
of this activity getting in here later tonight. If it does develop
a cold pool and begin to bow out, then it could bring some severe
wind gusts into portions of southern IN and KY later this evening,
mainly west of I-65. Once this moves through, the rest of the
overnight period will be mainly dry as upper-level ridging builds
overhead.
The ridge will really take hold Monday into Monday night, bringing
mostly dry and hot conditions. Can`t completely rule out a stray
storm Monday afternoon, but forcing mechanisms are lacking and the
mid-level cap will be strong. Therefore, will go with a dry
forecast. Highs will be in the low to mid 90s, with heat indices in
excess of 100 degrees at times. Overnight lows on Monday will be
quite muggy out ahead of another system slated to push through on
Tuesday, with readings only dropping into the mid and upper 70s.
.LONG TERM (Tuesday through Sunday)...
Issued at 220 PM EDT Sun Jun 21 2015
Models have not changed much in their overall pattern, with a ridge
near but centered just southwest of the region early on and then
transition to a more dominant western ridge by the end of the work
week, with troughing over us. That should mean hot days at first
and a little cooler by the end of the work week, but with rain
chances pretty much every day.
&&
.AVIATION (00Z TAF Update)...
Updated at 711 PM EDT Sun Jun 21 2015
Kept a couple hours of VCTS in the BWG TAF for the cells that are
currently in the area plus new ones attempting to come in from
western Kentucky. Also went ahead and put in a couple hours of VCTS
at SDF in case the convection currently over central Indiana can
survive all the way to the airport. LEX should remain high and dry
for the foreseeable future.
With the rain that fell at BWG this evening and with lighter winds
expected tonight than last night, included some high-end MVFR BR for
a few hours toward dawn. A cirrus canopy overhead will help to keep
the fog from getting out of hand (and possibly from forming at all).
Ridging will keep us dry tomorrow other than perhaps a stray cell in
the afternoon.
&&
.LMK WATCHES/WARNINGS/ADVISORIES...
KY...NONE.
IN...NONE.
&&
$$
Update.........13
Short Term.....KJD
Long Term......RJS
Aviation.......13
AREA FORECAST DISCUSSION...UPDATED
NWS GRAY ME
1201 PM EDT MON JUN 22 2015
.SYNOPSIS...
HIGH PRESSURE WILL BUILD OVER THE REGION TODAY AND WILL SHIFT
OFFSHORE TONIGHT. A COLD FRONT WILL CROSS THE AREA ON TUESDAY.
HIGH PRESSURE WILL BUILD IN FROM THE WEST TUESDAY NIGHT AND
WEDNESDAY AND WILL SHIFT OFFSHORE ON THURSDAY. WEAK LOW PRESSURE
WILL PASS SOUTH OF NEW ENGLAND FRIDAY THROUGH FRIDAY NIGHT. HIGH
PRESSURE WILL BUILD IN FROM THE NORTHEAST SATURDAY AND WILL HOLD
OVER THE REGION ON SUNDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
UPDATE...HAVE ADJUSTED GRIDS TO BETTER MATCH LATEST OBSERVATIONAL
TRENDS. CLOUDS HAVE THINNED...BUT SUNSHINE AND COLD POOL ALOFT ARE
COMBINING TO PRODUCE ABUNDANT DIURNAL CU. THERE WILL BE SCATTERED
SHOWERS FROM THESE...ESPECIALLY FAR WRN ME AS THEY DRIFT OFF THE
ELEVATED HEAT SOURCE IN THE MTNS.
PREV DISC...
LATEST RADAR IMAGERY CONTINUES TO SHOW SHOWER ACTIVITY...SOME OF
IT HEAVY...EXITING INTO EASTERN AREAS...WITH A SECOND BATCH OF
SHOWERS NOW CROSSING INTO THE MOUNTAINS. THIS IS IN ASSOCIATION
WITH A SHORT WAVE MOVING OVER NORTHERN MAINE EARLY THIS MORNING.
LATEST HRRR RUN SHOWS THIS LARGE BAND EXITING OFF THE COAST BY
12Z...WITH ADDITIONAL SHOWERS MOVING ACROSS THE MOUNTAINS AND INTO
CENTRAL MAINE TODAY.
ABSENCE OF NORTHWEST GRADIENT BEHIND THE DEPARTING REMAINS OF
TROPICAL DEPRESSION BILL WILL COMPLICATE THE FORECAST FOR TODAY.
WITH LACK OF DOWNSLOPING AND ONLY THE ADVECTION OF SLIGHTLY DRIER
AIR INTO THE REGION TODAY...EXPECT MOISTURE AND CLOUDS TO REMAIN
IN PLACE. CU WILL ALSO DEVELOP DURING THE DAY WITH A COLD POOL
REMAINING ALOFT AND CYCLONIC FLOW OVER THE REGION.
MAXIMUM TEMPERATURES WILL NEED TO BE MODIFIED DOWNWARDS ONCE
AGAIN. THIS IS A COOLER FORECAST...HOWEVER SOUTHERNMOST NEW
HAMPSHIRE SHOULD STILL REACH THE LOWER 80S WITH SOME ADDITIONAL
SUNSHINE.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM TUESDAY/...
UPDATE...CURSORY GLANCE AT OVERNIGHT HI-RES GUIDANCE AND 12Z NAM
RUN CONTINUE TO ADVERTISE A POTENTIALLY HIGHER END SEVERE WEATHER
THREAT TUE AFTERNOON ACROSS PARTS OF THE FORECAST AREA. THE
GREATEST QUESTION REGARDING THREAT AREA REVOLVES AROUND
MORNING...ELEVATED...NON-SEVERE TSTMS THAT ARE FORECAST TO CROSS
PARTS OF NEW ENGLAND. CONVECTION ALLOWING GUIDANCE BRINGS THIS
FEATURE NEWD THRU NRN ZONES...LEAVING THE S MAINLY RAIN AND CLOUD
FREE. THIS WOULD ALLOW AMPLE HEATING AND INSTABILITY TO
DEVELOP...INCREASING THE THREAT FOR SEVERE STORMS. SOME
GUIDANCE...LIKE THE 12Z NAM...BRINGS IT MORE EWD AND THRU THE
CENTRAL FORECAST AREA. THIS WOULD DELAY DESTABILIZATION AND
DECREASE THE SEVERE THREAT...OR PUSH IT FARTHER S.
PREVIOUS DISCUSSION...PATCHY FOG WILL FORM TONIGHT UNDER LIGHT
WINDS AND THE PRESENCE OF LOW LEVEL MOISTURE. THIS WILL KEEP LOWS
MAINLY IN THE 50S SOUTH OF THE MOUNTAINS.
BY TUESDAY...MODELS BEGIN TO DIVERGE ON THE NORTHERN EXTENT THE
WARM SECTOR REACHES IN OUR FORECAST AREA. ALL MODELS DEVELOP A
WAVE ALONG THE FRONTAL BOUNDARIES THAT WILL BE CROSSING THE
FORECAST AREA TUESDAY AFTERNOON. SOUTH OF THIS WAVE...CAPE VALUES
BRIEFLY INCREASE TO OVER 1000 J/KG AS STRONG JET MAX ENTERS THE
REGION ALOFT. THIS WILL AID IN SHOWER AND THUNDERSTORM
DEVELOPMENT...WITH THE GREATEST THREAT FOR SEVERE STORMS BEING
OVER SOUTHERN NEW HAMPSHIRE AND SOUTHWEST MAINE. DAMAGING WIND
GUSTS WOULD BE THE PRIMARY THREAT...WHICH SPC HAS ALSO HIGHLIGHTED
IN THEIR DISCUSSIONS. HAVE INCLUDED ENHANCED WORDING IN THE
FORECAST.
PRECIPITABLE WATER VALUES WILL BE CLOSE TO 2 INCHES.
HOWEVER...FAST MOVEMENT OF STORMS SHOULD LIMIT HEAVY RAIN
POTENTIAL. NEVERTHELESS...ANY TRAINING STORMS COULD DROP LOCALLY
HEAVY RAINFALL.
&&
.LONG TERM /TUESDAY NIGHT THROUGH SUNDAY/...
COLD FRONT WILL SHIFT OFFSHORE TUESDAY EVENING AND ANY
LINGERING CLOUDS WILL CLEAR OVERNIGHT AS HIGH PRESSURE
BUILDS IN FROM THE WEST. LOWS WILL GENERALLY RANGE
THROUGH THE 50S TO NEAR 60.
REMAINDER OF THE WEEK AND INTO THE WEEKEND LOOKING QUIET
AS HIGH PRESSURE STAYS IN CONTROL ACROSS THE NORTHEAST.
VERY WEAK SECONDARY COLD FRONT MAY PRODUCE ENOUGH INSTABILITY
IN FAR NORTHERN ZONES LATE IN THE DAY WEDNESDAY TO PRODUCE A
FEW SCATTERED SHOWERS AND THUNDERSTORMS...BUT THE REMAINDER OF
THE FORECAST AREA SHOULD SEE A DRY DAY WITH MOSTLY SUNNY SKIES
AND SEASONABLE TEMPS.
HIGH PRESSURE WILL PUSH OFF THE NEW ENGLAND COAST ON THURSDAY
PRODUCING ANOTHER MOSTLY SUNNY DAY WITH HIGHS RANGING THROUGH
THE 70S.
ONLY POSSIBLE SPOILER WILL COME ON FRIDAY AS WEAK LOW PRESSURE
FORECAST TO TRACK EAST ALONG A STALLED FRONTAL BOUNDARY INTO
SOUTHERN NEW ENGLAND. AT THIS POINT APPEARS ANY ASSOCIATED
PRECIP WILL REMAIN SOUTH OF THE FORECAST AREA WITH JUST HIGH
AND MID LEVEL CLOUDINESS PASSING THROUGH SOUTHERN NEW HAMPSHIRE
AND MAINE. DEPENDING ON THE ECMWF`S TAKE ON THIS...MAY INCLUDE
SOME LOW CHANCE POPS FOR LATE FRIDAY AND FRIDAY NIGHT IN
SOUTHERN NEW HAMPSHIRE...BUT EXPECT ANY SHOWERS TO BE LIGHT AND
SPOTTY MAINLY FRIDAY NIGHT.
HIGH PRESSURE BUILDING IN FROM THE NORTHEAST WILL HELP TO SUPPRESS
THIS FRONTAL BOUNDARY TO THE SOUTH ON SATURDAY AS SEVERAL MORE
WEAK AREAS OF LOW PRESSURE TRACK EAST ALONG IT. INCREASING ONSHORE
FLOW MAY HAVE OCEAN STRATUS FLIRTING WITH SOUTHERN NEW HAMPSHIRE.
EXPECT THE MAJORITY OF THE AREA TO SEE AT LEAST PARTLY SUNNY SKIES
WITH SEASONABLE TEMPS.
FAIR WEATHER WILL PERSIST ACROSS THE REGION AGAIN ON SUNDAY AND
MONDAY AS HIGH PRESSURE STRENGTHENS OVER THE REGION.
&&
.AVIATION /16Z MONDAY THROUGH FRIDAY/...
SHORT TERM...AREAS IFR AND LIFR IN PATCHY FOG EARLY THIS MORNING.
CONDITIONS LOWERING AGAIN TONIGHT WITH PATCHY FOG REDEVELOPING.
ISOLATED LIFR CONDITIONS IN STRONG STORMS BY TUESDAY AFTERNOON.
LONG TERM...VFR TUESDAY NIGHT THROUGH FRIDAY.
&&
.MARINE...
SHORT TERM...WINDS AND SEAS WILL APPROACH SMALL CRAFT ADVISORY
THRESHOLDS TUESDAY AHEAD/ALONG THE FRONTAL SYSTEMS.
LONG TERM...NO PROBLEMS NOTED.
&&
.GYX WATCHES/WARNINGS/ADVISORIES...
ME...NONE.
NH...NONE.
MARINE...NONE.
&&
$$
NEAR TERM...LEGRO
SHORT TERM...LEGRO
AREA FORECAST DISCUSSION
NWS CARIBOU ME
1128 AM EDT MON JUN 22 2015
.SYNOPSIS...
AFTER AN UPPER TROUGH CROSSES THE REGION THIS MORNING...HIGH
PRESSURE WILL BUILD INTO THE AREA THIS AFTERNOON AND THEN SLIDE
EAST OF THE REGION TONIGHT. AN OCCLUDED FRONT WILL CROSS THE
REGION LATER TUESDAY THROUGH EARLY TUESDAY NIGHT. HIGH PRESSURE
RETURNS WEDNESDAY INTO THE WEEKEND.
&&
.NEAR TERM /THROUGH TONIGHT/...
11:30 UPDATE...DECREASED CLOUD COVER A BIT IN WESTERN AREAS AND
LOWERED TEMPS A BIT THROUGH THE MIDDAY HOURS. OTHERWISE, NO MAJOR
CHANGES.
ORGNL DISC: LATEST OBS HAVE INDICATED THE DISSIPATION OF FOG AND
MOST OF THE DZ AS WINDS BECAME NRLY OVR THE LAST 3 TO 6 HRS ACROSS
THE REGION. LATEST RADAR REF IMAGERY SHOWS SOME SHWRS FROM A
FAIRLY LARGE AREA OF RNFL OVR NRN NH AND WRN ME BEGINNING TO CROSS
OVR INTO THE CNTRL HIGHLANDS AND WRN DOWNEAST PTNS OF OUR FA.
LATEST HRLY HRRR MODEL SIM RADAR REF SHOWS SOME OF THIS SHWR
ACTIVITY TO CONT OVR MSLY OUR SW ZONES INTO THE MORN HRS AS A
WEAKENING UPPER TROF CROSSES W TO E ACROSS THE FA...WITH UP TO A
TENTH OF AN INCH AND LCLY MORE OF RNFL OVR LCTNS BORDERING MID ME.
WHATS LEFT OF ANY SHWR ACTIVITY SHOULD THEN LARGELY DISSIPATE BY
AFTN AS THE UPPER TROF SLIDES E OF THE FA INTO THE MARITIMES...
WITH DECREASING CLDNSS BY MID TO LATE AFTN OVR MOST LCTNS. A RIDGE
OF SFC HIGH PRES SHOULD THEN PROVIDE FAIR SKIES WITH CLR-PTLY CLDY
SKIES INTO THE OVRNGT HRS.
A MDTLY STRONG S/WV TROF AND ASSOCIATED OCCLUDED FRONT MOVING ENE
FROM S CNTRL CAN INTO QB WILL BRING AN INCREASING BL-850MB RETURN
SSW WIND LATE TNGT...WITH SREF CATEGORY CLG PROBS SUGGESTING THE
NWRD ADVC OF MARINE ST FROM THE NRN GULF OF ME INTO OUR FA BY
DAYBREAK TUE. THIS MAY BE IN ADVC OF THE HI/MID CLD CANOPY AHEAD
OF THE OCCLUDED FRONT.
HI TEMPS TDY SHOULD BE WARMER BY 5 TO 10 DEG F ACROSS THE REGION
COMPARED TO YSTDY...BUT STILL 4 TO 8 DEG F BELOW AVG FOR THIS TM
OF SEASON. OVRNGT LOWS WILL BE HELD UP TO NEAR NORMAL DUE TO
INCREASING WINDS AND POTENTIAL CLD CVR LATE AT NGT.
&&
.SHORT TERM /TUESDAY THROUGH WEDNESDAY NIGHT/...
FOR TUESDAY...A FAST MOVING OCCLUDED FRONT WILL MOVE INTO THE
AREA. A SOUTHEASTERLY SURFACE FLOW WILL ENSURE THE MORNING STARTS
WITH LOW CLOUDS AND THESE STABLE LOW LEVEL CLOUDS WILL PERSIST
UNTIL THE FRONT HAS CLEARED THE AREA TUESDAY EVENING. THIS WILL
KEEP HIGHS IN THE UPPER 50S TO LOWER 60S RAIN WILL RAPIDLY MOVE IN
FROM WEST TO EAST DURING THE MORNING AND SHOULD COVER THE ENTIRE
FORECAST AREA BY MIDDAY. THERE WILL BE A DECENT AMOUNT OF RAIN
WITH THIS FRONTAL SYSTEM WITH A SHARP UPPER TROUGH THAT WILL HAVE
SOME NEGATIVE TILT...A STRONG LOW LEVEL JET AND THE LEFT EXIT
REGION OF A STRONG UPPER JET. THESE FACTORS ALSO POINT TO ELEVATED
CONVECTION DURING THE AFTERNOON. THE CASE FOR THUNDERSTORMS IS
FURTHER STRENGTHENED BY DIFFLUENCE ALOFT...A STRONG LOW LEVEL
THERMAL RIDGE JUST ABOVE THE INVERSION AND DECENT MUCAPE. MOST
AREAS SHOULD RECEIVE THE BETTER PART OF A HALF INCH WITH HEAVIER
AMOUNTS IN THUNDERSTORMS. PRECIPITATION WILL MOVE RAPIDLY OUT OF
THE DOWN EAST REGION IN THE EARLY EVENING BUT WILL TEND TO LINGER
TOWARDS THE CROWN OF MAINE THROUGH MIDNIGHT. CLEARING ARRIVES
AFTER MIDNIGHT WITH LOWS IN THE LOW TO MID 50S. A DRY WESTERLY
FLOW IS EXPECTED FOR WEDNESDAY WITH LITTLE LOW LEVEL MOISTURE AND
LOW HUMIDITY. WELL-MIXED LOW LEVELS WILL PRODUCE GUSTS TO 25 MPH.
AN UPPER TROUGH WILL CROSS THE AREA IN THE AFTERNOON AND MAY SET
OFF A FEW SHOWERS...BUT THE LACK OF MOISTURE WILL BE A DETERMENT
TO WIDESPREAD SHOWER ACTIVITY. HIGHS WILL RANGE FROM THE UPPER 60S
IN THE SAINT JOHN VALLEY TO THE MID 70S FOR BANGOR AND DOWN EAST
WHERE THE WESTERLY FLOW WILL PREVENT ANY ONSHORE FLOW OF COLD
MARINE AIR. A COOL AND CLEAR NIGHT FOLLOWS WEDNESDAY NIGHT WITH
LOWS IN THE UPPER 40S TO LOWER 50S.
&&
.LONG TERM /THURSDAY THROUGH SUNDAY/...
HIGH PRESSURE IS EXPECTED TO BE IN CONTROL THROUGH THE PERIOD WITH
LOW HUMIDITY AND PLEASANT TEMPERATURES. A FEW LIGHT AFTERNOON
SHOWERS CANNOT BE RULED OUT WITH DIURNAL HEATING AND MINOR UPPER
TROUGHS ROTATING AROUND AN UPPER LOW IN THE CANADIAN
MARITIMES...BUT WILL NOT ASSIGN POPS ANY HIGHER THAN SLIGHT CHC.
THURSDAY WILL BE QUITE WINDY WITH GUSTS TOWARDS 30 MPH...BUT WINDS
WILL DECREASE FOR FRIDAY AND SATURDAY. THE NEXT ORGANIZED WEATHER
SYSTEM MAY ARRIVE LATER SUNDAY. AN ONSHORE FLOW MAY ALSO COMMENCE
SUNDAY AS THE HIGH MOVES EAST AND HAVE INCREASED CLOUDINESS FOR
SUNDAY.
&&
.AVIATION /16Z MONDAY THROUGH FRIDAY/...
NEAR TERM: MOST SITES WILL BE RECOVERING FROM MVFR CLGS THIS MORN
TO VFR THIS AFTN. VFR CONDITIONS SHOULD CONT INTO THIS EVE...WITH
SREF MODEL CLG CATEGORY PROBS SUGGESTING THE RETURN OF MARINE LOW
MVFR AND PERHAPS IFR ST FROM S TO N ACROSS THE FA LATE TNGT AS
RETURN BL-850MB S WINDS BEGIN TO INCREASE.
SHORT TERM: MVFR TEMPO IFR TUESDAY AND TUESDAY EVENING DUE TO CIGS
AND HEAVIER SHOWERS. EMBEDDED THUNDERSTORMS ARE POSSIBLE TUESDAY
AFTERNOON. EXPECT VFR FROM LATER TUESDAY EVENING THROUGH FRIDAY.
&&
.MARINE...
NEAR TERM: NO HDLNS XPCTD TDY THRU TNGT...WITH ANY LEFT OVR MARINE
FOG LIFTING ERLY THIS MORN. WENT WITH ABOUT 85 PERCENT OF WW3 WV
GUIDANCE THRU THE NEAR TERM FOR OUR WATERS THIS UPDATE.
SHORT TERM: THERE IS A STRONG CASE FOR AN SCA TUESDAY INTO TUESDAY
EVENING DUE TO A STRONG PRESSURE GRADIENT CREATING GUSTS TO 30 KTS
AND SEAS GRADUALLY BUILDING OVER 5 FT. WILL HOLD OFF ON ISSUING
NOW...BUT CONFIDENCE IS HIGH. ALSO ANTICIPATE THUNDERSTORMS OVER
THE WATERS LATER TUESDAY. A PERIOD OF FOG IS ALSO LIKELY TUESDAY
EVENING. NO SIGNIFICANT WEATHER IS EXPECTED FROM LATER TUESDAY
NIGHT THROUGH NEXT WEEKEND.
&&
.CAR WATCHES/WARNINGS/ADVISORIES...
ME...NONE.
MARINE...NONE.
&&
$$
NEAR TERM...VJN/MCB
SHORT TERM...MCW
LONG TERM...MCW
AVIATION...VJN/MCW
MARINE...VJN/MCW
AREA FORECAST DISCUSSION
NWS CARIBOU ME
825 AM EDT MON JUN 22 2015
.SYNOPSIS...
AFTER AN UPPER TROUGH CROSSES THE REGION THIS MORNING...HIGH
PRESSURE WILL BUILD INTO THE AREA THIS AFTERNOON AND THEN SLIDE
EAST OF THE REGION TONIGHT. AN OCCLUDED FRONT WILL CROSS THE
REGION LATER TUESDAY THROUGH EARLY TUESDAY NIGHT. HIGH PRESSURE
RETURNS WEDNESDAY INTO THE WEEKEND.
&&
.NEAR TERM /THROUGH TONIGHT/...
8:30 AM UPDATE...A FEW BREAKS IN THE OVERCAST ARE OCCURING IN
WESTERN AREAS SO CUT BACK ON CLOUD COVER JUST A LITTLE BIT TO THE
WEST. OTHERWISE, NO MAJOR CHANGES THIS HOUR.
ORGNL DISC: LATEST OBS HAVE INDICATED THE DISSIPATION OF FOG AND
MOST OF THE DZ AS WINDS BECAME NRLY OVR THE LAST 3 TO 6 HRS ACROSS
THE REGION. LATEST RADAR REF IMAGERY SHOWS SOME SHWRS FROM A
FAIRLY LARGE AREA OF RNFL OVR NRN NH AND WRN ME BEGINNING TO CROSS
OVR INTO THE CNTRL HIGHLANDS AND WRN DOWNEAST PTNS OF OUR FA.
LATEST HRLY HRRR MODEL SIM RADAR REF SHOWS SOME OF THIS SHWR
ACTIVITY TO CONT OVR MSLY OUR SW ZONES INTO THE MORN HRS AS A
WEAKENING UPPER TROF CROSSES W TO E ACROSS THE FA...WITH UP TO A
TENTH OF AN INCH AND LCLY MORE OF RNFL OVR LCTNS BORDERING MID ME.
WHATS LEFT OF ANY SHWR ACTIVITY SHOULD THEN LARGELY DISSIPATE BY
AFTN AS THE UPPER TROF SLIDES E OF THE FA INTO THE MARITIMES...
WITH DECREASING CLDNSS BY MID TO LATE AFTN OVR MOST LCTNS. A RIDGE
OF SFC HIGH PRES SHOULD THEN PROVIDE FAIR SKIES WITH CLR-PTLY CLDY
SKIES INTO THE OVRNGT HRS.
A MDTLY STRONG S/WV TROF AND ASSOCIATED OCCLUDED FRONT MOVING ENE
FROM S CNTRL CAN INTO QB WILL BRING AN INCREASING BL-850MB RETURN
SSW WIND LATE TNGT...WITH SREF CATEGORY CLG PROBS SUGGESTING THE
NWRD ADVC OF MARINE ST FROM THE NRN GULF OF ME INTO OUR FA BY
DAYBREAK TUE. THIS MAY BE IN ADVC OF THE HI/MID CLD CANOPY AHEAD
OF THE OCCLUDED FRONT.
HI TEMPS TDY SHOULD BE WARMER BY 5 TO 10 DEG F ACROSS THE REGION
COMPARED TO YSTDY...BUT STILL 4 TO 8 DEG F BELOW AVG FOR THIS TM
OF SEASON. OVRNGT LOWS WILL BE HELD UP TO NEAR NORMAL DUE TO
INCREASING WINDS AND POTENTIAL CLD CVR LATE AT NGT.
&&
.SHORT TERM /TUESDAY THROUGH WEDNESDAY NIGHT/...
FOR TUESDAY...A FAST MOVING OCCLUDED FRONT WILL MOVE INTO THE
AREA. A SOUTHEASTERLY SURFACE FLOW WILL ENSURE THE MORNING STARTS
WITH LOW CLOUDS AND THESE STABLE LOW LEVEL CLOUDS WILL PERSIST
UNTIL THE FRONT HAS CLEARED THE AREA TUESDAY EVENING. THIS WILL
KEEP HIGHS IN THE UPPER 50S TO LOWER 60S RAIN WILL RAPIDLY MOVE IN
FROM WEST TO EAST DURING THE MORNING AND SHOULD COVER THE ENTIRE
FORECAST AREA BY MIDDAY. THERE WILL BE A DECENT AMOUNT OF RAIN
WITH THIS FRONTAL SYSTEM WITH A SHARP UPPER TROUGH THAT WILL HAVE
SOME NEGATIVE TILT...A STRONG LOW LEVEL JET AND THE LEFT EXIT
REGION OF A STRONG UPPER JET. THESE FACTORS ALSO POINT TO ELEVATED
CONVECTION DURING THE AFTERNOON. THE CASE FOR THUNDERSTORMS IS
FURTHER STRENGTHENED BY DIFFLUENCE ALOFT...A STRONG LOW LEVEL
THERMAL RIDGE JUST ABOVE THE INVERSION AND DECENT MUCAPE. MOST
AREAS SHOULD RECEIVE THE BETTER PART OF A HALF INCH WITH HEAVIER
AMOUNTS IN THUNDERSTORMS. PRECIPITATION WILL MOVE RAPIDLY OUT OF
THE DOWN EAST REGION IN THE EARLY EVENING BUT WILL TEND TO LINGER
TOWARDS THE CROWN OF MAINE THROUGH MIDNIGHT. CLEARING ARRIVES
AFTER MIDNIGHT WITH LOWS IN THE LOW TO MID 50S. A DRY WESTERLY
FLOW IS EXPECTED FOR WEDNESDAY WITH LITTLE LOW LEVEL MOISTURE AND
LOW HUMIDITY. WELL-MIXED LOW LEVELS WILL PRODUCE GUSTS TO 25 MPH.
AN UPPER TROUGH WILL CROSS THE AREA IN THE AFTERNOON AND MAY SET
OFF A FEW SHOWERS...BUT THE LACK OF MOISTURE WILL BE A DETERMENT
TO WIDESPREAD SHOWER ACTIVITY. HIGHS WILL RANGE FROM THE UPPER 60S
IN THE SAINT JOHN VALLEY TO THE MID 70S FOR BANGOR AND DOWN EAST
WHERE THE WESTERLY FLOW WILL PREVENT ANY ONSHORE FLOW OF COLD
MARINE AIR. A COOL AND CLEAR NIGHT FOLLOWS WEDNESDAY NIGHT WITH
LOWS IN THE UPPER 40S TO LOWER 50S.
&&
.LONG TERM /THURSDAY THROUGH SUNDAY/...
HIGH PRESSURE IS EXPECTED TO BE IN CONTROL THROUGH THE PERIOD WITH
LOW HUMIDITY AND PLEASANT TEMPERATURES. A FEW LIGHT AFTERNOON
SHOWERS CANNOT BE RULED OUT WITH DIURNAL HEATING AND MINOR UPPER
TROUGHS ROTATING AROUND AN UPPER LOW IN THE CANADIAN
MARITIMES...BUT WILL NOT ASSIGN POPS ANY HIGHER THAN SLIGHT CHC.
THURSDAY WILL BE QUITE WINDY WITH GUSTS TOWARDS 30 MPH...BUT WINDS
WILL DECREASE FOR FRIDAY AND SATURDAY. THE NEXT ORGANIZED WEATHER
SYSTEM MAY ARRIVE LATER SUNDAY. AN ONSHORE FLOW MAY ALSO COMMENCE
SUNDAY AS THE HIGH MOVES EAST AND HAVE INCREASED CLOUDINESS FOR
SUNDAY.
&&
.AVIATION /13Z MONDAY THROUGH FRIDAY/...
NEAR TERM: MOST SITES WILL BE RECOVERING FROM MVFR CLGS THIS MORN
TO VFR THIS AFTN. VFR CONDITIONS SHOULD CONT INTO THIS EVE...WITH
SREF MODEL CLG CATEGORY PROBS SUGGESTING THE RETURN OF MARINE LOW
MVFR AND PERHAPS IFR ST FROM S TO N ACROSS THE FA LATE TNGT AS
RETURN BL-850MB S WINDS BEGIN TO INCREASE.
SHORT TERM: MVFR TEMPO IFR TUESDAY AND TUESDAY EVENING DUE TO CIGS
AND HEAVIER SHOWERS. EMBEDDED THUNDERSTORMS ARE POSSIBLE TUESDAY
AFTERNOON. EXPECT VFR FROM LATER TUESDAY EVENING THROUGH FRIDAY.
&&
.MARINE...
NEAR TERM: NO HDLNS XPCTD TDY THRU TNGT...WITH ANY LEFT OVR MARINE
FOG LIFTING ERLY THIS MORN. WENT WITH ABOUT 85 PERCENT OF WW3 WV
GUIDANCE THRU THE NEAR TERM FOR OUR WATERS THIS UPDATE.
SHORT TERM: THERE IS A STRONG CASE FOR AN SCA TUESDAY INTO TUESDAY
EVENING DUE TO A STRONG PRESSURE GRADIENT CREATING GUSTS TO 30 KTS
AND SEAS GRADUALLY BUILDING OVER 5 FT. WILL HOLD OFF ON ISSUING
NOW...BUT CONFIDENCE IS HIGH. ALSO ANTICIPATE THUNDERSTORMS OVER
THE WATERS LATER TUESDAY. A PERIOD OF FOG IS ALSO LIKELY TUESDAY
EVENING. NO SIGNIFICANT WEATHER IS EXPECTED FROM LATER TUESDAY
NIGHT THROUGH NEXT WEEKEND.
&&
.CAR WATCHES/WARNINGS/ADVISORIES...
ME...NONE.
MARINE...NONE.
&&
$$
NEAR TERM...VJN/MCB
SHORT TERM...MCW
LONG TERM...MCW
AVIATION...VJN/MCW
MARINE...VJN/MCW
AREA FORECAST DISCUSSION
NWS GRAY ME
722 AM EDT MON JUN 22 2015
.SYNOPSIS...
HIGH PRESSURE WILL BUILD OVER THE REGION TODAY AND WILL SHIFT
OFFSHORE TONIGHT. A COLD FRONT WILL CROSS THE AREA ON TUESDAY.
HIGH PRESSURE WILL BUILD IN FROM THE WEST TUESDAY NIGHT AND
WEDNESDAY AND WILL SHIFT OFFSHORE ON THURSDAY. WEAK LOW PRESSURE
WILL PASS SOUTH OF NEW ENGLAND FRIDAY THROUGH FRIDAY NIGHT. HIGH
PRESSURE WILL BUILD IN FROM THE NORTHEAST SATURDAY AND WILL HOLD
OVER THE REGION ON SUNDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
UPDATE...
HAVE UPDATED THE GRIDS BASED ON CURRENT CONDITIONS. MESOSCALE
MODELS CONTINUE TO ADVECT AND DEVELOP SHOWERS OVER CENTRAL AND
NORTHERN AREAS TODAY. THIS PRECIPITATION OCCURS IN ASSOCIATION
WITH A COLD POOL AND CYCLONIC FLOW ALOFT.
PREV DISC...
LATEST RADAR IMAGERY CONTINUES TO SHOW SHOWER ACTIVITY...SOME OF
IT HEAVY...EXITING INTO EASTERN AREAS...WITH A SECOND BATCH OF
SHOWERS NOW CROSSING INTO THE MOUNTAINS. THIS IS IN ASSOCIATION
WITH A SHORT WAVE MOVING OVER NORTHERN MAINE EARLY THIS MORNING.
LATEST HRRR RUN SHOWS THIS LARGE BAND EXITING OFF THE COAST BY
12Z...WITH ADDITIONAL SHOWERS MOVING ACROSS THE MOUNTAINS AND INTO
CENTRAL MAINE TODAY.
ABSENCE OF NORTHWEST GRADIENT BEHIND THE DEPARTING REMAINS OF
TROPICAL DEPRESSION BILL WILL COMPLICATE THE FORECAST FOR TODAY.
WITH LACK OF DOWNSLOPING AND ONLY THE ADVECTION OF SLIGHTLY DRIER
AIR INTO THE REGION TODAY...EXPECT MOISTURE AND CLOUDS TO REMAIN
IN PLACE. CU WILL ALSO DEVELOP DURING THE DAY WITH A COLD POOL
REMAINING ALOFT AND CYCLONIC FLOW OVER THE REGION.
MAXIMUM TEMPERATURES WILL NEED TO BE MODIFIED DOWNWARDS ONCE
AGAIN. THIS IS A COOLER FORECAST...HOWEVER SOUTHERNMOST NEW
HAMPSHIRE SHOULD STILL REACH THE LOWER 80S WITH SOME ADDITIONAL
SUNSHINE.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM TUESDAY/...
PATCHY FOG WILL FORM TONIGHT UNDER LIGHT WINDS AND THE PRESENCE OF
LOW LEVEL MOISTURE. THIS WILL KEEP LOWS MAINLY IN THE 50S SOUTH OF
THE MOUNTAINS.
BY TUESDAY...MODELS BEGIN TO DIVERGE ON THE NORTHERN EXTENT THE
WARM SECTOR REACHES IN OUR FORECAST AREA. ALL MODELS DEVELOP A
WAVE ALONG THE FRONTAL BOUNDARYS THAT WILL BE CROSSING THE
FORECAST AREA TUESDAY AFTERNOON. SOUTH OF THIS WAVE...CAPE VALUES
BRIEFLY INCREASE TO OVER 1000 J/KG AS STRONG JET MAX ENTERS THE
REGION ALOFT. THIS WILL AID IN SHOWER AND THUNDERSTORM
DEVELOPMENT...WITH THE GREATEST THREAT FOR SEVERE STORMS BEING
OVER SOUTHERN NEW HAMPSHIRE AND SOUTHWEST MAINE. DAMAGING WIND
GUSTS WOULD BE THE PRIMARY THREAT...WHICH SPC HAS ALSO HIGHLIGHTED
IN THEIR DISCUSSIONS. HAVE INCLUDED ENHANCED WORDING IN THE
FORECAST.
PRECIPITABLE WATER VALUES WILL BE CLOSE TO 2 INCHES.
HOWEVER...FAST MOVEMENT OF STORMS SHOULD LIMIT HEAVY RAIN
POTENTIAL. NEVERTHELESS...ANY TRAINING STORMS COULD DROP LOCALLY
HEAVY RAINFALL.
&&
.LONG TERM /TUESDAY NIGHT THROUGH SUNDAY/...
COLD FRONT WILL SHIFT OFFSHORE TUESDAY EVENING AND ANY
LINGERING CLOUDS WILL CLEAR OVERNIGHT AS HIGH PRESSURE
BUILDS IN FROM THE WEST. LOWS WILL GENERALLY RANGE
THROUGH THE 50S TO NEAR 60.
REMAINDER OF THE WEEK AND INTO THE WEEKEND LOOKING QUIET
AS HIGH PRESSURE STAYS IN CONTROL ACROSS THE NORTHEAST.
VERY WEAK SECONDARY COLD FRONT MAY PRODUCE ENOUGH INSTABILITY
IN FAR NORTHERN ZONES LATE IN THE DAY WEDNESDAY TO PRODUCE A
FEW SCATTERED SHOWERS AND THUNDERSTORMS...BUT THE REMAINDER OF
THE FORECAST AREA SHOULD SEE A DRY DAY WITH MOSTLY SUNNY SKIES
AND SEASONABLE TEMPS.
HIGH PRESSURE WILL PUSH OFF THE NEW ENGLAND COAST ON THURSDAY
PRODUCING ANOTHER MOSTLY SUNNY DAY WITH HIGHS RANGING THROUGH
THE 70S.
ONLY POSSIBLE SPOILER WILL COME ON FRIDAY AS WEAK LOW PRESSURE
FORECAST TO TRACK EAST ALONG A STALLED FRONTAL BOUNDARY INTO
SOUTHERN NEW ENGLAND. AT THIS POINT APPEARS ANY ASSOCIATED
PRECIP WILL REMAIN SOUTH OF THE FORECAST AREA WITH JUST HIGH
AND MID LEVEL CLOUDINESS PASSING THROUGH SOUTHERN NEW HAMPSHIRE
AND MAINE. DEPENDING ON THE ECMWF`S TAKE ON THIS...MAY INCLUDE
SOME LOW CHANCE POPS FOR LATE FRIDAY AND FRIDAY NIGHT IN
SOUTHERN NEW HAMPSHIRE...BUT EXPECT ANY SHOWERS TO BE LIGHT AND
SPOTTY MAINLY FRIDAY NIGHT.
HIGH PRESSURE BUILDING IN FROM THE NORTHEAST WILL HELP TO SUPPRESS
THIS FRONTAL BOUNDARY TO THE SOUTH ON SATURDAY AS SEVERAL MORE
WEAK AREAS OF LOW PRESSURE TRACK EAST ALONG IT. INCREASING ONSHORE
FLOW MAY HAVE OCEAN STRATUS FLIRTING WITH SOUTHERN NEW HAMPSHIRE.
EXPECT THE MAJORITY OF THE AREA TO SEE AT LEAST PARTLY SUNNY SKIES
WITH SEASONABLE TEMPS.
FAIR WEATHER WILL PERSIST ACROSS THE REGION AGAIN ON SUNDAY AND
MONDAY AS HIGH PRESSURE STRENGTHENS OVER THE REGION.
&&
.AVIATION /12Z MONDAY THROUGH FRIDAY/...
SHORT TERM...AREAS IFR AND LIFR IN PATCHY FOG EARLY THIS MORNING.
CONDITIONS LOWERING AGAIN TONIGHT WITH PATCHY FOG REDEVELOPING.
ISOLATED LIFR CONDITIONS IN STRONG STORMS BY TUESDAY AFTERNOON.
LONG TERM...VFR TUESDAY NIGHT THROUGH FRIDAY.
&&
.MARINE...
SHORT TERM...WINDS AND SEAS WILL APPROACH SMALL CRAFT ADVISORY
THRESHOLDS TUESDAY AHEAD/ALONG THE FRONTAL SYSTEMS.
LONG TERM...NO PROBLEMS NOTED.
&&
.GYX WATCHES/WARNINGS/ADVISORIES...
ME...NONE.
NH...NONE.
MARINE...NONE.
&&
$$
JC
AREA FORECAST DISCUSSION
NWS CARIBOU ME
622 AM EDT MON JUN 22 2015
.SYNOPSIS...
AFTER AN UPPER TROUGH CROSSES THE REGION THIS MORNING...HIGH
PRESSURE WILL BUILD INTO THE AREA THIS AFTERNOON AND THEN SLIDE
EAST OF THE REGION TONIGHT. AN OCCLUDED FRONT WILL CROSS THE
REGION LATER TUESDAY THROUGH EARLY TUESDAY NIGHT. HIGH PRESSURE
RETURNS WEDNESDAY INTO THE WEEKEND.
&&
.NEAR TERM /THROUGH TONIGHT/...
615 AM UPDATE: BASED ON RADAR REF INTENSITY AND CVRG...WE
INCREASED POPS INTO THE LIKELY RANGE ERLY THIS MORN FOR PTNS OF
XTRM SW PTNS OF OUR FA. CORRESPONDING 6 HRLY QPFS WERE ALSO
INCREASED TO REF MDT RNFL RATES TIL ABOUT 9 AM EDT.
ORGNL DISC: LATEST OBS HAVE INDICATED THE DISSIPATION OF FOG AND
MOST OF THE DZ AS WINDS BECAME NRLY OVR THE LAST 3 TO 6 HRS ACROSS
THE REGION. LATEST RADAR REF IMAGERY SHOWS SOME SHWRS FROM A
FAIRLY LARGE AREA OF RNFL OVR NRN NH AND WRN ME BEGINNING TO CROSS
OVR INTO THE CNTRL HIGHLANDS AND WRN DOWNEAST PTNS OF OUR FA.
LATEST HRLY HRRR MODEL SIM RADAR REF SHOWS SOME OF THIS SHWR
ACTIVITY TO CONT OVR MSLY OUR SW ZONES INTO THE MORN HRS AS A
WEAKENING UPPER TROF CROSSES W TO E ACROSS THE FA...WITH UP TO A
TENTH OF AN INCH AND LCLY MORE OF RNFL OVR LCTNS BORDERING MID ME.
WHATS LEFT OF ANY SHWR ACTIVITY SHOULD THEN LARGELY DISSIPATE BY
AFTN AS THE UPPER TROF SLIDES E OF THE FA INTO THE MARITIMES...
WITH DECREASING CLDNSS BY MID TO LATE AFTN OVR MOST LCTNS. A RIDGE
OF SFC HIGH PRES SHOULD THEN PROVIDE FAIR SKIES WITH CLR-PTLY CLDY
SKIES INTO THE OVRNGT HRS.
A MDTLY STRONG S/WV TROF AND ASSOCIATED OCCLUDED FRONT MOVING ENE
FROM S CNTRL CAN INTO QB WILL BRING AN INCREASING BL-850MB RETURN
SSW WIND LATE TNGT...WITH SREF CATEGORY CLG PROBS SUGGESTING THE
NWRD ADVC OF MARINE ST FROM THE NRN GULF OF ME INTO OUR FA BY
DAYBREAK TUE. THIS MAY BE IN ADVC OF THE HI/MID CLD CANOPY AHEAD
OF THE OCCLUDED FRONT.
HI TEMPS TDY SHOULD BE WARMER BY 5 TO 10 DEG F ACROSS THE REGION
COMPARED TO YSTDY...BUT STILL 4 TO 8 DEG F BELOW AVG FOR THIS TM
OF SEASON. OVRNGT LOWS WILL BE HELD UP TO NEAR NORMAL DUE TO
INCREASING WINDS AND POTENTIAL CLD CVR LATE AT NGT.
&&
.SHORT TERM /TUESDAY THROUGH WEDNESDAY NIGHT/...
FOR TUESDAY...A FAST MOVING OCCLUDED FRONT WILL MOVE INTO THE
AREA. A SOUTHEASTERLY SURFACE FLOW WILL ENSURE THE MORNING STARTS
WITH LOW CLOUDS AND THESE STABLE LOW LEVEL CLOUDS WILL PERSIST
UNTIL THE FRONT HAS CLEARED THE AREA TUESDAY EVENING. THIS WILL
KEEP HIGHS IN THE UPPER 50S TO LOWER 60S RAIN WILL RAPIDLY MOVE IN
FROM WEST TO EAST DURING THE MORNING AND SHOULD COVER THE ENTIRE
FORECAST AREA BY MIDDAY. THERE WILL BE A DECENT AMOUNT OF RAIN
WITH THIS FRONTAL SYSTEM WITH A SHARP UPPER TROUGH THAT WILL HAVE
SOME NEGATIVE TILT...A STRONG LOW LEVEL JET AND THE LEFT EXIT
REGION OF A STRONG UPPER JET. THESE FACTORS ALSO POINT TO ELEVATED
CONVECTION DURING THE AFTERNOON. THE CASE FOR THUNDERSTORMS IS
FURTHER STRENGTHENED BY DIFFLUENCE ALOFT...A STRONG LOW LEVEL
THERMAL RIDGE JUST ABOVE THE INVERSION AND DECENT MUCAPE. MOST
AREAS SHOULD RECEIVE THE BETTER PART OF A HALF INCH WITH HEAVIER
AMOUNTS IN THUNDERSTORMS. PRECIPITATION WILL MOVE RAPIDLY OUT OF
THE DOWN EAST REGION IN THE EARLY EVENING BUT WILL TEND TO LINGER
TOWARDS THE CROWN OF MAINE THROUGH MIDNIGHT. CLEARING ARRIVES
AFTER MIDNIGHT WITH LOWS IN THE LOW TO MID 50S. A DRY WESTERLY
FLOW IS EXPECTED FOR WEDNESDAY WITH LITTLE LOW LEVEL MOISTURE AND
LOW HUMIDITY. WELL-MIXED LOW LEVELS WILL PRODUCE GUSTS TO 25 MPH.
AN UPPER TROUGH WILL CROSS THE AREA IN THE AFTERNOON AND MAY SET
OFF A FEW SHOWERS...BUT THE LACK OF MOISTURE WILL BE A DETERMENT
TO WIDESPREAD SHOWER ACTIVITY. HIGHS WILL RANGE FROM THE UPPER 60S
IN THE SAINT JOHN VALLEY TO THE MID 70S FOR BANGOR AND DOWN EAST
WHERE THE WESTERLY FLOW WILL PREVENT ANY ONSHORE FLOW OF COLD
MARINE AIR. A COOL AND CLEAR NIGHT FOLLOWS WEDNESDAY NIGHT WITH
LOWS IN THE UPPER 40S TO LOWER 50S.
&&
.LONG TERM /THURSDAY THROUGH SUNDAY/...
HIGH PRESSURE IS EXPECTED TO BE IN CONTROL THROUGH THE PERIOD WITH
LOW HUMIDITY AND PLEASANT TEMPERATURES. A FEW LIGHT AFTERNOON
SHOWERS CANNOT BE RULED OUT WITH DIURNAL HEATING AND MINOR UPPER
TROUGHS ROTATING AROUND AN UPPER LOW IN THE CANADIAN
MARITIMES...BUT WILL NOT ASSIGN POPS ANY HIGHER THAN SLIGHT CHC.
THURSDAY WILL BE QUITE WINDY WITH GUSTS TOWARDS 30 MPH...BUT WINDS
WILL DECREASE FOR FRIDAY AND SATURDAY. THE NEXT ORGANIZED WEATHER
SYSTEM MAY ARRIVE LATER SUNDAY. AN ONSHORE FLOW MAY ALSO COMMENCE
SUNDAY AS THE HIGH MOVES EAST AND HAVE INCREASED CLOUDINESS FOR
SUNDAY.
&&
.AVIATION /07Z MONDAY THROUGH FRIDAY/...
NEAR TERM: MOST SITES WILL BE RECOVERING FROM MVFR CLGS THIS MORN
TO VFR THIS AFTN. VFR CONDITIONS SHOULD CONT INTO THIS EVE...WITH
SREF MODEL CLG CATEGORY PROBS SUGGESTING THE RETURN OF MARINE LOW
MVFR AND PERHAPS IFR ST FROM S TO N ACROSS THE FA LATE TNGT AS
RETURN BL-850MB S WINDS BEGIN TO INCREASE.
SHORT TERM: MVFR TEMPO IFR TUESDAY AND TUESDAY EVENING DUE TO CIGS
AND HEAVIER SHOWERS. EMBEDDED THUNDERSTORMS ARE POSSIBLE TUESDAY
AFTERNOON. EXPECT VFR FROM LATER TUESDAY EVENING THROUGH FRIDAY.
&&
.MARINE...
NEAR TERM: NO HDLNS XPCTD TDY THRU TNGT...WITH ANY LEFT OVR MARINE
FOG LIFTING ERLY THIS MORN. WENT WITH ABOUT 85 PERCENT OF WW3 WV
GUIDANCE THRU THE NEAR TERM FOR OUR WATERS THIS UPDATE.
SHORT TERM: THERE IS A STRONG CASE FOR AN SCA TUESDAY INTO TUESDAY
EVENING DUE TO A STRONG PRESSURE GRADIENT CREATING GUSTS TO 30 KTS
AND SEAS GRADUALLY BUILDING OVER 5 FT. WILL HOLD OFF ON ISSUING
NOW...BUT CONFIDENCE IS HIGH. ALSO ANTICIPATE THUNDERSTORMS OVER
THE WATERS LATER TUESDAY. A PERIOD OF FOG IS ALSO LIKELY TUESDAY
EVENING. NO SIGNIFICANT WEATHER IS EXPECTED FROM LATER TUESDAY
NIGHT THROUGH NEXT WEEKEND.
&&
.CAR WATCHES/WARNINGS/ADVISORIES...
ME...NONE.
MARINE...NONE.
&&
$$
NEAR TERM...VJN
SHORT TERM...MCW
LONG TERM...MCW
AVIATION...VJN/MCW
MARINE...VJN/MCW
AREA FORECAST DISCUSSION
NWS CARIBOU ME
550 AM EDT MON JUN 22 2015
.SYNOPSIS...
AFTER AN UPPER TROUGH CROSSES THE REGION THIS MORNING...HIGH
PRESSURE WILL BUILD INTO THE AREA THIS AFTERNOON AND THEN SLIDE
EAST OF THE REGION TONIGHT. AN OCCLUDED FRONT WILL CROSS THE
REGION LATER TUESDAY THROUGH EARLY TUESDAY NIGHT. HIGH PRESSURE
RETURNS WEDNESDAY INTO THE WEEKEND.
&&
.NEAR TERM /THROUGH TONIGHT/...
535 AM UPDATE: ONLY CHGS MADE THIS UPDATE WAS TO ADD PATCHY DZ TIL
9 AM AND MINOR CHGS TO FCST HRLY TEMPS TIL MIDDAY BASED ON 5 AM
OBS.
ORGNL DISC: LATEST OBS HAVE INDICATED THE DISSIPATION OF FOG AND
MOST OF THE DZ AS WINDS BECAME NRLY OVR THE LAST 3 TO 6 HRS ACROSS
THE REGION. LATEST RADAR REF IMAGERY SHOWS SOME SHWRS FROM A
FAIRLY LARGE AREA OF RNFL OVR NRN NH AND WRN ME BEGINNING TO CROSS
OVR INTO THE CNTRL HIGHLANDS AND WRN DOWNEAST PTNS OF OUR FA.
LATEST HRLY HRRR MODEL SIM RADAR REF SHOWS SOME OF THIS SHWR
ACTIVITY TO CONT OVR MSLY OUR SW ZONES INTO THE MORN HRS AS A
WEAKENING UPPER TROF CROSSES W TO E ACROSS THE FA...WITH UP TO A
TENTH OF AN INCH AND LCLY MORE OF RNFL OVR LCTNS BORDERING MID ME.
WHATS LEFT OF ANY SHWR ACTIVITY SHOULD THEN LARGELY DISSIPATE BY
AFTN AS THE UPPER TROF SLIDES E OF THE FA INTO THE MARITIMES...
WITH DECREASING CLDNSS BY MID TO LATE AFTN OVR MOST LCTNS. A RIDGE
OF SFC HIGH PRES SHOULD THEN PROVIDE FAIR SKIES WITH CLR-PTLY CLDY
SKIES INTO THE OVRNGT HRS.
A MDTLY STRONG S/WV TROF AND ASSOCIATED OCCLUDED FRONT MOVING ENE
FROM S CNTRL CAN INTO QB WILL BRING AN INCREASING BL-850MB RETURN
SSW WIND LATE TNGT...WITH SREF CATEGORY CLG PROBS SUGGESTING THE
NWRD ADVC OF MARINE ST FROM THE NRN GULF OF ME INTO OUR FA BY
DAYBREAK TUE. THIS MAY BE IN ADVC OF THE HI/MID CLD CANOPY AHEAD
OF THE OCCLUDED FRONT.
HI TEMPS TDY SHOULD BE WARMER BY 5 TO 10 DEG F ACROSS THE REGION
COMPARED TO YSTDY...BUT STILL 4 TO 8 DEG F BELOW AVG FOR THIS TM
OF SEASON. OVRNGT LOWS WILL BE HELD UP TO NEAR NORMAL DUE TO
INCREASING WINDS AND POTENTIAL CLD CVR LATE AT NGT.
&&
.SHORT TERM /TUESDAY THROUGH WEDNESDAY NIGHT/...
FOR TUESDAY...A FAST MOVING OCCLUDED FRONT WILL MOVE INTO THE
AREA. A SOUTHEASTERLY SURFACE FLOW WILL ENSURE THE MORNING STARTS
WITH LOW CLOUDS AND THESE STABLE LOW LEVEL CLOUDS WILL PERSIST
UNTIL THE FRONT HAS CLEARED THE AREA TUESDAY EVENING. THIS WILL
KEEP HIGHS IN THE UPPER 50S TO LOWER 60S RAIN WILL RAPIDLY MOVE IN
FROM WEST TO EAST DURING THE MORNING AND SHOULD COVER THE ENTIRE
FORECAST AREA BY MIDDAY. THERE WILL BE A DECENT AMOUNT OF RAIN
WITH THIS FRONTAL SYSTEM WITH A SHARP UPPER TROUGH THAT WILL HAVE
SOME NEGATIVE TILT...A STRONG LOW LEVEL JET AND THE LEFT EXIT
REGION OF A STRONG UPPER JET. THESE FACTORS ALSO POINT TO ELEVATED
CONVECTION DURING THE AFTERNOON. THE CASE FOR THUNDERSTORMS IS
FURTHER STRENGTHENED BY DIFFLUENCE ALOFT...A STRONG LOW LEVEL
THERMAL RIDGE JUST ABOVE THE INVERSION AND DECENT MUCAPE. MOST
AREAS SHOULD RECEIVE THE BETTER PART OF A HALF INCH WITH HEAVIER
AMOUNTS IN THUNDERSTORMS. PRECIPITATION WILL MOVE RAPIDLY OUT OF
THE DOWN EAST REGION IN THE EARLY EVENING BUT WILL TEND TO LINGER
TOWARDS THE CROWN OF MAINE THROUGH MIDNIGHT. CLEARING ARRIVES
AFTER MIDNIGHT WITH LOWS IN THE LOW TO MID 50S. A DRY WESTERLY
FLOW IS EXPECTED FOR WEDNESDAY WITH LITTLE LOW LEVEL MOISTURE AND
LOW HUMIDITY. WELL-MIXED LOW LEVELS WILL PRODUCE GUSTS TO 25 MPH.
AN UPPER TROUGH WILL CROSS THE AREA IN THE AFTERNOON AND MAY SET
OFF A FEW SHOWERS...BUT THE LACK OF MOISTURE WILL BE A DETERMENT
TO WIDESPREAD SHOWER ACTIVITY. HIGHS WILL RANGE FROM THE UPPER 60S
IN THE SAINT JOHN VALLEY TO THE MID 70S FOR BANGOR AND DOWN EAST
WHERE THE WESTERLY FLOW WILL PREVENT ANY ONSHORE FLOW OF COLD
MARINE AIR. A COOL AND CLEAR NIGHT FOLLOWS WEDNESDAY NIGHT WITH
LOWS IN THE UPPER 40S TO LOWER 50S.
&&
.LONG TERM /THURSDAY THROUGH SUNDAY/...
HIGH PRESSURE IS EXPECTED TO BE IN CONTROL THROUGH THE PERIOD WITH
LOW HUMIDITY AND PLEASANT TEMPERATURES. A FEW LIGHT AFTERNOON
SHOWERS CANNOT BE RULED OUT WITH DIURNAL HEATING AND MINOR UPPER
TROUGHS ROTATING AROUND AN UPPER LOW IN THE CANADIAN
MARITIMES...BUT WILL NOT ASSIGN POPS ANY HIGHER THAN SLIGHT CHC.
THURSDAY WILL BE QUITE WINDY WITH GUSTS TOWARDS 30 MPH...BUT WINDS
WILL DECREASE FOR FRIDAY AND SATURDAY. THE NEXT ORGANIZED WEATHER
SYSTEM MAY ARRIVE LATER SUNDAY. AN ONSHORE FLOW MAY ALSO COMMENCE
SUNDAY AS THE HIGH MOVES EAST AND HAVE INCREASED CLOUDINESS FOR
SUNDAY.
&&
.AVIATION /07Z MONDAY THROUGH FRIDAY/...
NEAR TERM: MOST SITES WILL BE RECOVERING FROM MVFR CLGS THIS MORN
TO VFR THIS AFTN. VFR CONDITIONS SHOULD CONT INTO THIS EVE...WITH
SREF MODEL CLG CATEGORY PROBS SUGGESTING THE RETURN OF MARINE LOW
MVFR AND PERHAPS IFR ST FROM S TO N ACROSS THE FA LATE TNGT AS
RETURN BL-850MB S WINDS BEGIN TO INCREASE.
SHORT TERM: MVFR TEMPO IFR TUESDAY AND TUESDAY EVENING DUE TO CIGS
AND HEAVIER SHOWERS. EMBEDDED THUNDERSTORMS ARE POSSIBLE TUESDAY
AFTERNOON. EXPECT VFR FROM LATER TUESDAY EVENING THROUGH FRIDAY.
&&
.MARINE...
NEAR TERM: NO HDLNS XPCTD TDY THRU TNGT...WITH ANY LEFT OVR MARINE
FOG LIFTING ERLY THIS MORN. WENT WITH ABOUT 85 PERCENT OF WW3 WV
GUIDANCE THRU THE NEAR TERM FOR OUR WATERS THIS UPDATE.
SHORT TERM: THERE IS A STRONG CASE FOR AN SCA TUESDAY INTO TUESDAY
EVENING DUE TO A STRONG PRESSURE GRADIENT CREATING GUSTS TO 30 KTS
AND SEAS GRADUALLY BUILDING OVER 5 FT. WILL HOLD OFF ON ISSUING
NOW...BUT CONFIDENCE IS HIGH. ALSO ANTICIPATE THUNDERSTORMS OVER
THE WATERS LATER TUESDAY. A PERIOD OF FOG IS ALSO LIKELY TUESDAY
EVENING. NO SIGNIFICANT WEATHER IS EXPECTED FROM LATER TUESDAY
NIGHT THROUGH NEXT WEEKEND.
&&
.CAR WATCHES/WARNINGS/ADVISORIES...
ME...NONE.
MARINE...NONE.
&&
$$
NEAR TERM...VJN
SHORT TERM...MCW
LONG TERM...MCW
AVIATION...VJN/MCW
MARINE...VJN/MCW
AREA FORECAST DISCUSSION
NWS GRAY ME
522 AM EDT MON JUN 22 2015
.SYNOPSIS...
HIGH PRESSURE WILL BUILD OVER THE REGION TODAY AND WILL SHIFT
OFFSHORE TONIGHT. A COLD FRONT WILL CROSS THE AREA ON TUESDAY.
HIGH PRESSURE WILL BUILD IN FROM THE WEST TUESDAY NIGHT AND
WEDNESDAY AND WILL SHIFT OFFSHORE ON THURSDAY. WEAK LOW PRESSURE
WILL PASS SOUTH OF NEW ENGLAND FRIDAY THROUGH FRIDAY NIGHT. HIGH
PRESSURE WILL BUILD IN FROM THE NORTHEAST SATURDAY AND WILL HOLD
OVER THE REGION ON SUNDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
515 AM UPDATE...
LATEST RADAR IMAGERY CONTINUES TO SHOW SHOWER ACTIVITY...SOME OF
IT HEAVY...EXITING INTO EASTERN AREAS...WITH A SECOND BATCH OF
SHOWERS NOW CROSSING INTO THE MOUNTAINS. THIS IS IN ASSOCIATION
WITH A SHORT WAVE MOVING OVER NORTHERN MAINE EARLY THIS MORNING.
LATEST HRRR RUN SHOWS THIS LARGE BAND EXITING OFF THE COAST BY
12Z...WITH ADDITIONAL SHOWERS MOVING ACROSS THE MOUNTAINS AND INTO
CENTRAL MAINE TODAY.
ABSENCE OF NORTHWEST GRADIENT BEHIND THE DEPARTING REMAINS OF
TROPICAL DEPRESSION BILL WILL COMPLICATE THE FORECAST FOR TODAY.
WITH LACK OF DOWNSLOPING AND ONLY THE ADVECTION OF SLIGHTLY DRIER
AIR INTO THE REGION TODAY...EXPECT MOISTURE AND CLOUDS TO REMAIN
IN PLACE. CU WILL ALSO DEVELOP DURING THE DAY WITH A COLD POOL
REMAINING ALOFT AND CYCLONIC FLOW OVER THE REGION.
MAXIMUM TEMPERATURES WILL NEED TO BE MODIFIED DOWNWARDS ONCE
AGAIN. THIS IS A COOLER FORECAST...HOWEVER SOUTHERNMOST NEW
HAMPSHIRE SHOULD STILL REACH THE LOWER 80S WITH SOME ADDITIONAL
SUNSHINE.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM TUESDAY/...
PATCHY FOG WILL FORM TONIGHT UNDER LIGHT WINDS AND THE PRESENCE OF
LOW LEVEL MOISTURE. THIS WILL KEEP LOWS MAINLY IN THE 50S SOUTH OF
THE MOUNTAINS.
BY TUESDAY...MODELS BEGIN TO DIVERGE ON THE NORTHERN EXTENT THE
WARM SECTOR REACHES IN OUR FORECAST AREA. ALL MODELS DEVELOP A
WAVE ALONG THE FRONTAL BOUNDARYS THAT WILL BE CROSSING THE
FORECAST AREA TUESDAY AFTERNOON. SOUTH OF THIS WAVE...CAPE VALUES
BRIEFLY INCREASE TO OVER 1000 J/KG AS STRONG JET MAX ENTERS THE
REGION ALOFT. THIS WILL AID IN SHOWER AND THUNDERSTORM
DEVELOPMENT...WITH THE GREATEST THREAT FOR SEVERE STORMS BEING
OVER SOUTHERN NEW HAMPSHIRE AND SOUTHWEST MAINE. DAMAGING WIND
GUSTS WOULD BE THE PRIMARY THREAT...WHICH SPC HAS ALSO HIGHLIGHTED
IN THEIR DISCUSSIONS. HAVE INCLUDED ENHANCED WORDING IN THE
FORECAST.
PRECIPITABLE WATER VALUES WILL BE CLOSE TO 2 INCHES.
HOWEVER...FAST MOVEMENT OF STORMS SHOULD LIMIT HEAVY RAIN
POTENTIAL. NEVERTHELESS...ANY TRAINING STORMS COULD DROP LOCALLY
HEAVY RAINFALL.
&&
.LONG TERM /TUESDAY NIGHT THROUGH SUNDAY/...
COLD FRONT WILL SHIFT OFFSHORE TUESDAY EVENING AND ANY
LINGERING CLOUDS WILL CLEAR OVERNIGHT AS HIGH PRESSURE
BUILDS IN FROM THE WEST. LOWS WILL GENERALLY RANGE
THROUGH THE 50S TO NEAR 60.
REMAINDER OF THE WEEK AND INTO THE WEEKEND LOOKING QUIET
AS HIGH PRESSURE STAYS IN CONTROL ACROSS THE NORTHEAST.
VERY WEAK SECONDARY COLD FRONT MAY PRODUCE ENOUGH INSTABILITY
IN FAR NORTHERN ZONES LATE IN THE DAY WEDNESDAY TO PRODUCE A
FEW SCATTERED SHOWERS AND THUNDERSTORMS...BUT THE REMAINDER OF
THE FORECAST AREA SHOULD SEE A DRY DAY WITH MOSTLY SUNNY SKIES
AND SEASONABLE TEMPS.
HIGH PRESSURE WILL PUSH OFF THE NEW ENGLAND COAST ON THURSDAY
PRODUCING ANOTHER MOSTLY SUNNY DAY WITH HIGHS RANGING THROUGH
THE 70S.
ONLY POSSIBLE SPOILER WILL COME ON FRIDAY AS WEAK LOW PRESSURE
FORECAST TO TRACK EAST ALONG A STALLED FRONTAL BOUNDARY INTO
SOUTHERN NEW ENGLAND. AT THIS POINT APPEARS ANY ASSOCIATED
PRECIP WILL REMAIN SOUTH OF THE FORECAST AREA WITH JUST HIGH
AND MID LEVEL CLOUDINESS PASSING THROUGH SOUTHERN NEW HAMPSHIRE
AND MAINE. DEPENDING ON THE ECMWF`S TAKE ON THIS...MAY INCLUDE
SOME LOW CHANCE POPS FOR LATE FRIDAY AND FRIDAY NIGHT IN
SOUTHERN NEW HAMPSHIRE...BUT EXPECT ANY SHOWERS TO BE LIGHT AND
SPOTTY MAINLY FRIDAY NIGHT.
HIGH PRESSURE BUILDING IN FROM THE NORTHEAST WILL HELP TO SUPPRESS
THIS FRONTAL BOUNDARY TO THE SOUTH ON SATURDAY AS SEVERAL MORE
WEAK AREAS OF LOW PRESSURE TRACK EAST ALONG IT. INCREASING ONSHORE
FLOW MAY HAVE OCEAN STRATUS FLIRTING WITH SOUTHERN NEW HAMPSHIRE.
EXPECT THE MAJORITY OF THE AREA TO SEE AT LEAST PARTLY SUNNY SKIES
WITH SEASONABLE TEMPS.
FAIR WEATHER WILL PERSIST ACROSS THE REGION AGAIN ON SUNDAY AND
MONDAY AS HIGH PRESSURE STRENGTHENS OVER THE REGION.
&&
.AVIATION /10Z MONDAY THROUGH FRIDAY/...
SHORT TERM...AREAS IFR AND LIFR IN PATCHY FOG EARLY THIS MORNING.
CONDITIONS LOWERING AGAIN TONIGHT WITH PATCHY FOG REDEVELOPING.
ISOLATED LIFR CONDITIONS IN STRONG STORMS BY TUESDAY AFTERNOON.
LONG TERM...VFR TUESDAY NIGHT THROUGH FRIDAY.
&&
.MARINE...
SHORT TERM...WINDS AND SEAS WILL APPROACH SMALL CRAFT ADVISORY
THRESHOLDS TUESDAY AHEAD/ALONG THE FRONTAL SYSTEMS.
LONG TERM...NO PROBLEMS NOTED.
&&
.GYX WATCHES/WARNINGS/ADVISORIES...
ME...NONE.
NH...NONE.
MARINE...NONE.
&&
$$
JC
AREA FORECAST DISCUSSION
NWS GRAND RAPIDS MI
552 PM EDT MON JUN 22 2015
LATEST UPDATE...
MESOSCALE DISCUSSION/MARINE
.MESOSCALE DISCUSSION...
ISSUED AT 552 PM EDT MON JUN 22 2015
ALTHOUGH WE ARE CURRENTLY CATCHING A BREAK...THE LARGE SCALE
ENVIRONMENT STILL REMAINS FAVORABLE FOR SUPERCELLS THIS EVENING
AND THE HI RES MODELS SUCH AS THE HRRR AND THE NCAR ENSEMBLE
SHOWS POTENTIAL FOR STORMS AHEAD OF THE COLD FRONT TO AFFECT THE
FORECAST AREA FROM ABOUT 01Z TO 05Z. WE WILL CONTINUE TO WATCH THE
PROGRESS OF THE STORMS ACROSS WISCONSIN AND ILLINOIS.
&&
.SYNOPSIS...
ISSUED AT 328 PM EDT MON JUN 22 2015
SEVERE THUNDERSTORMS ARE POSSIBLE THIS EVENING AHEAD OF A COLD
FRONT. THE STORMS SHOULD BE ENDING SHORTLY AFTER MIDNIGHT. THEN
CLEARING AND LESS HUMID WEATHER IS EXPECTED FOR TUESDAY MORNING.
FAIR WEATHER SHOULD CONTINUE INTO WEDNESDAY THEN MORE SHOWERS AND
THUNDERSTORMS ARE EXPECTED ON THURSDAY.
&&
.SHORT TERM...(THIS EVENING THROUGH WEDNESDAY NIGHT)
ISSUED AT 328 PM EDT MON JUN 22 2015
SEVERE WEATHER THREAT CONTINUES THIS EVENING WITH SHEAR PROFILES
AND HELICITY VALUES CONDUCIVE TO SUPERCELLS. INSTABILITY WILL
INCREASE AS ATMOSPHERE QUICKLY RECOVERS FROM THE STORMS THIS
AFTERNOON. HI RES MODELS SUCH AS THE HRR AND NCAR ENSEMBLE SHOWS
THE STORMS ARRIVING BY 9 PM AND ENDING AROUND 1 AM. THE MAIN
THREAT WILL BE DOWNBURSTS...WITH TORNADOES AND LARGE HAIL FROM THE
MORE PERSISTENT UPDRAFTS.
DRYING TAKES PLACE LATER TONIGHT WITH COLD FROPA AND FAIR WEATHER
IS EXPECTED THROUGH WEDNESDAY. THE FRONT STALLS SOUTH OF LOWER
MICHIGAN AND RETURNS AS A WARM FRONT...SO RAIN IS COMING BACK FOR
WEDNESDAY EVENING AND ESPECIALLY LATE WEDNESDAY NIGHT.
&&
.LONG TERM...(THURSDAY THROUGH MONDAY)
ISSUED AT 328 PM EDT MON JUN 22 2015
MAIN EVENT IN THE EXTENDED IS A BATCH OF RAIN AND EMBEDDED
THUNDERSTORMS ON THURSDAY AS SFC LOW TRACKS ACROSS THE SOUTHERN
FORECAST AREA. ELEVATED INSTABILITY AND INCREASING SHEAR SHOULD
ALLOW ORGANIZED CONVECTION...PERHAPS AN MCS...TO AFFECT AT LEAST
THE SOUTHERN HALF OF THE FORECAST AREA.
THE UPPER FLOW AMPLIFIES OVER THE WEEKEND AND COOLER AND CLOUDY
WEATHER.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON)
ISSUED AT 142 PM EDT MON JUN 22 2015
SHOWERS AND THUNDERSTORMS WILL BRING SOME PERIODS OF IFR
CONDITIONS THROUGH 06Z. BRIEF LIFR AND WINDS OVER 40 KNOTS ARE
ALSO POSSIBLE...ALONG WITH THE THREATS OF HAIL AND A TORNADO THIS
EVENING.
CONDITIONS SHOULD IMPROVE TO VFR AFTER 06Z. SOUTH TO SOUTHWEST
WINDS WILL GUST OVER 20 KNOTS THROUGH THIS EVENING...EVEN OUTSIDE
OF THUNDERSTORMS. WINDS WILL GO NORTHWEST AND DECREASE TO AROUND
10 KNOTS LATE TONIGHT.
&&
.MARINE...
ISSUED AT 552 PM EDT MON JUN 22 2015
HAVE ISSUED A GALE WARNING FOR ALL THE NEARSHORE ZONES. STRONG
ENVIRONMENTAL WINDS MIXING DOWN THIS EVENING...AND PERHAPS
OVERNIGHT...COULD SEE GUSTS TO 35 KNOTS PERSIST FOR SEVERAL HOURS.
THERE IS ALSO THE CHANCE FOR STRONG TO SEVERE THUNDERSTORMS FROM
ABOUT 8 PM TO 10 PM.
&&
.HYDROLOGY...
ISSUED AT 233 PM EDT MON JUN 22 2015
STRONG THUNDERSTORMS SO FAR THIS AFTERNOON HAVE PRODUCED HEAVY
RAINFALL IN SHORT AMOUNTS OF TIME. REPORTS SO FAR HAVE RANGED
BETWEEN A HALF INCH AND ONE INCH IN 30-45 MINUTES. BRIEF VERY HEAVY
RAINFALL MAY OVERWHELM STORM DRAINS AND CAUSE LOCALIZED
FLOODING...ESPECIALLY IN URBAN AND LOW-LYING AREAS.
THUNDERSTORMS WILL PROGRESS ACROSS SOUTHWEST LOWER MICHIGAN THROUGH
4 PM OR SO...WITH A LULL EXPECTED FROM LATE AFTERNOON THROUGH EARLY
EVENING. A SECOND ROUND OF STRONG TO SEVERE THUNDERSTORMS CAPABLE OF
HEAVY RAINFALL AND FLOODING IS EXPECTED FROM AROUND 8 PM THIS
EVENING THROUGH MIDNIGHT. THE RAINFALL THIS AFTERNOON AND EVENING
WILL CAUSE RISES ON AREA RIVERS AND STREAMS THIS EVENING THROUGH THE
REST OF THE WEEK. ADDITIONAL RIVER FLOOD ADVISORIES MAY BE NECESSARY
FOR RIVERS EXCEEDING BANKFULL.
BEYOND LATE THIS EVENING...THE POTENTIAL FOR HEAVY RAINFALL IS LOW.
WE COULD SEE LIGHT RAIN ON THURSDAY WITH A FRONTAL SYSTEM MOVING
THROUGH.
&&
.GRR WATCHES/WARNINGS/ADVISORIES...
MI...BEACH HAZARDS STATEMENT THROUGH TUESDAY MORNING FOR MIZ037-043-
050-056-064-071.
LM...GALE WARNING UNTIL 5 AM EDT TUESDAY FOR LMZ844>849.
&&
$$
MESOSCALE...OSTUNO
SYNOPSIS...OSTUNO
SHORT TERM...OSTUNO
LONG TERM...OSTUNO
AVIATION...OSTUNO
HYDROLOGY...EBW
MARINE...OSTUNO
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
418 PM EDT MON JUN 22 2015
.SHORT TERM...(THIS EVENING THROUGH TUESDAY)
ISSUED AT 418 PM EDT MON JUN 22 2015
WV IMAGERY AND RAP ANALYSIS INDICATED A ZONAL PATTERN ACROSS THE NRN
CONUS WITH A SHORTWAVE TROUGH FROM NW ONTARIO INTO NRN MN. THE
RESIDUAL MCV GENERATED FROM THE LARGE MCS EARLIER TODAY WAS LOCATED
NEAR NW LOWER MI. FORCING ASSOCIATED WITH THIS FEATURE AND 305K-310K
ISENTROPIC ASCENT AHEAD OF THE SHRTWV SUPPORTED SOME SHRA OVER NRN
UPPER MI. AT THE SFC...A COLD FRONT EXTENDED ACROSS ERN MN. SCT SHRA
AND ISOLATED TS HAS ALSO DEVELOPED ALONG AND AHEAD OF THE FRONT
WHERE HEIGHT FALLS AHEAD OF THE SHRTWV WERE MOVING IN.
CLOUDS AND AREAS OF SHOWERS HAVE LIMITED HEATING/INSTABILITY WITH
HIGHEST SB/MU CAPE VALUES ONLY UP TO AROUND 500 J/KG OVER THE WEST.
EXPECT SCT SHRA/TSRA TO CONTINUE TO PUSH FROM NW WI THROUGH UPPER MI
THIS EVENING. ALTHOUGH 0-6KM/0-1KM SHEAR VALUES OF 40-60KT/25-35KT
WOULD BE FAVORABLE FOR SOME STRONG/SVR STORMS. EVEN WITH SOME
ADDITIONAL CAPE RECOVERY...THE MARGINAL INSTABILITY WILL LIMIT THE
SVR POTENTIAL. NEVERTHELESS...AN ISOLATED SVR STORM CANNOT BE RULED
OUT. THE SCT SHRA/TSRA ARE EXPECTED TO MOVE OUT OF THE CNTRL AND
EAST BTWN 03Z-06Z WITH DRY WEATHER THE REST OF THE NIGHT. GUSTY
WINDS WILL DEVELOP BEHIND THE FRONT AND LOW PRES WITH THE PRES RISE
MAX MOVING THROUGH THIS EVENING AND A TIGHT PRES GRADIENT LINGERING
OVERNIGHT.
TUE...HIGH PRES BUILDING FROM THE UPPER MS VALLEY INTO THE WRN GREAT
LAKES WITH MUCH DRIER AIR WILL BRING MOSTLY SUNNY SKIES...BREEZY NW
WINDS AND TEMPS NEAR SEASONAL AVERAGES FROM THE LOWER TO MID 70S.
.LONG TERM...(TUESDAY NIGHT THROUGH MONDAY)
ISSUED AT 325 PM EDT MON JUN 22 2015
SEVERAL SHORTWAVES WILL AFFECT THE UPPER GREAT LAKES REGION THROUGH
THE REST OF THE WORK WEEK AND INTO THE WEEKEND...WHICH WILL SLOWLY
DEVELOP AN UPPER TROUGH OVER THE GREAT LAKES REGION THIS WEEKEND.
ONCE THE UPPER TROUGH BECOMES ESTABLISHED IN THE GREAT LAKES
REGION...ECMWF/GFS ENSEMBLES ARE CONSISTENT ON THE UPPER RIDGE
DEVELOPING OVER THE PACIFIC NORTHWEST THIS WEEKEND TO SLOWLY SHIFT
TO THE NORTHWEST AND REMAIN IN PLACE THROUGH THE FIRST WEEK OF
JULY. THAT WILL LEAD TO A PERSISTENT PERIOD OF NORMAL TO BELOW
NORMAL TEMPERATURES FOR THE GREAT LAKES REGION.
SHIFTING BACK TO THIS WEEK...THE FIRST WAVE THAT WILL AFFECT THE
CWA WILL BE MOVING ACROSS FAR NORTHERN ONTARIO ON TUESDAY
NIGHT...WITH SOUTHWESTERN EDGE OF THAT WAVE BRUSHING THE NORTHEAST
PART OF LAKE SUPERIOR. AT THE SURFACE...A WEAK TROUGH WILL BE
MOVING ACROSS THE LAKE AND EXPECT THERE TO BE SOME SHOWERS ALONG IT
IN NORTHWEST ONTARIO ON TUESDAY AFTERNOON. BUT WITH THE LOSS OF
DIURNAL HEATING...LIMITED MOISTURE...AND THE BEST FORCING STAYING
WELL TO THE NORTHEAST OF THE CWA...WILL ONLY SHOW SLIGHT CHANCE
POPS MOVING SOUTHEAST ACROSS NORTHEAST LAKE SUPERIOR. DID BRUSH THE
KEWEENAW WITH THOSE SLIGHT CHANCE POPS WITH A DECENT NUMBER OF
MODELS SHOWING A FEW HUNDREDTHS OF QPF. OTHERWISE...EXPECT THE REST
OF THE AREA TO BE PARTLY CLOUDY TO MOSTLY CLEAR ON TUESDAY NIGHT DUE
TO THE RESIDUAL EFFECTS OF THE SLOWLY DEPARTING SURFACE RIDGE.
THAT SURFACE RIDGE WILL STILL BE OVER THE GREAT LAKES REGION ON
WEDNESDAY MORNING...AS THE PARENT HIGH MOVES INTO THE MID ATLANTIC
STATES. BUT THE NEXT SHORTWAVE WILL BE QUICKLY APPROACHING THE AREA
ON WEDNESDAY AFTERNOON. MODELS CONTINUE TO DEPICT LINGERING
MOISTURE ASSOCIATED WITH THE TUESDAY NIGHT SURFACE TROUGH BEING
OVER THE U.P. ON WEDNESDAY AFTERNOON AND THAT WILL COMBINE WITH THE
ARRIVAL OF ADDITIONAL MOISTURE/FORCING AND LAKE BREEZE DEVELOPMENT
TO LEAD TO SHOWERS AND A FEW THUNDERSTORMS OVER PORTIONS OF
WEST/CENTRAL UPPER MICHIGAN. WILL CONTINUE TO SHOW THE BEST CHANCE
FOR SHOWERS OVER THE LAND AREAS AND INLAND FROM THE GREAT
LAKES...WITH THE BEST OPPORTUNITY ALONG THE EXPECTED LAKE BREEZE
FROM CENTRAL MARQUETTE COUNTY WESTWARD TOWARDS ONTONAGON COUNTY.
WILL CONTINUE TO KEEP THUNDER VALUES IN THE SLIGHT CHANCE CATEGORY
WITH MLCAPE VALUES GENERALLY UNDER 500J/KG (BEST INSTABILITY WELL
TO THE SOUTH AND TIED TO THE STRONG STORMS LIKELY MOVING THROUGH
SOUTHERN MINNESOTA/WISCONSIN LATE WEDNESDAY AFTERNOON/NIGHT). 0-6KM
BULK SHEAR VALUES LOOK FAIRLY STRONG (APPROACHING 50KTS)...BUT
LOOKING AT THE SOUNDINGS...THAT IS ALL TIED TO THE STRONG JET
BETWEEN 5-6KM. THUS...THINK THE EFFECTIVE SHEAR VALUES AROUND 20KTS
ARE MORE REASONABLE AND BELIEVE THE POTENTIAL FOR STRONG STORMS IS
LIMITED AT THIS POINT. THE ONLY CONCERN WOULD BE WITH THE SLOW STORM
MOTIONS LEADING TO LOCALIZED HEAVY RAIN WHERE THE THUNDERSTORMS
OCCUR.
WHILE THAT FIRST WAVE WILL AFFECT THE AREA WEDNESDAY
AFTERNOON/EVENING...THERE ARE SEVERAL WEAK WAVES TRAILING IT THAT
WILL HAVE AN INFLUENCE ON THE WEATHER FOR THE U.P. THROUGH THURSDAY
NIGHT. WILL SHOW CHANCE POPS AS THESE DISTURBANCES MOVE THROUGH AND
CONTINUE SLIGHT CHANCE FOR THUNDER (ALTHOUGH THAT APPEARS TO BE
FAIRLY OPTIMISTIC). THOSE WAVES WILL AMPLIFY AN UPPER TROUGH OVER
THE GREAT LAKES REGION THIS WEEKEND AND LIKELY CONTINUE INTO EARLY
JULY. THERE IS THE POTENTIAL FOR SOME DIURNAL SHOWERS THIS
WEEKEND...ALTHOUGH THE SUBSIDENCE FROM A HIGH PRESSURE RIDGE MOVING
THROUGH SHOULD LIMIT THE COVERAGE...BEFORE ANOTHER STRONGER WAVE
DROPS SOUTHEAST ACROSS THE AREA ON MONDAY.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON)
ISSUED AT 152 PM EDT MON JUN 22 2015MID/HIGH A LEVEL CLOUDS OVER
THE AREA WILL SUPPRESS CHANCES FOR SHRA/TSRA THIS AFTERNOON.
HOWEVER...SOME HEATING LATE THIS AFTERNOON AHEAD OF A COLD FRONT MAY
STILL BE ENOUGH FOR SOME SHRA/TSRA TO DEVELOP. CONFIDENCE WAS NOT
HIGH ENOUGH THROUGH TO INCLUDE MENTION OF TS. A PERIOD OF MVFR CIGS
IS POSSIBLE ESPECIALLY AT CMX BEHIND THE FRONT...PER UPSTREAM TRENDS.
EXPECT GUSTY WINDS THIS AFTERNOON AHEAD OF THE COLD FRONT AND IN THE
EVENING BEHIND A COLD FRONT AT ALL SITES. WITH DRY ADVECTION BEHIND
THE FRONT EXPECT IMPROVEMENT TO VFR LATE EVENING AND OVERNIGHT.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 418 PM EDT MON JUN 22 2015
A LOW PRES SYSTEM WIL MOVE EAST OF LAKE SUPERIOR TONIGHT. A TIGHT
PRES GRADIENT AND COLD ADVECTION ON THE BACK SIDE OF THIS LOW WILL
SUPPORT A PERIOD OF WNW 35 KNOT GALES LATE TONIGHT INTO TUE
MORNING...STRONGEST OVER THE EAST HALF OF LAKE SUPERIOR. HIGH PRES
BUILDING BACK OVER THE AREA WILL THEN KEEP WINDS LIGHT AGAIN FROM
LATE TUE INTO FRI.
LINGERING LOW-LVL MOISTURE AND HIGH DEWPOINTS WILL SUPPORT FOG
ACROSS THE LAKE...THAT COULD BE LOCALLY DENSE INTO THIS EVENING.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
GALE WARNING FROM 1 AM TO 10 AM EDT TUESDAY FOR LSZ251-266-267.
LAKE MICHIGAN...
DENSE FOG ADVISORY UNTIL MIDNIGHT EDT TONIGHT FOR LMZ221-248-250.
&&
$$
SHORT TERM...JLB
LONG TERM...SRF
AVIATION...JLB
MARINE...JLB
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
326 PM EDT MON JUN 22 2015
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 522 AM EDT MON JUN 22 2015
WV IMAGERY AND RAP ANALYSIS INDICATES A ZONAL PATTERN ACROSS THE NRN
CONUS WITH A WELL-DEFINED SHORTWAVE TROUGH UPSTREAM OVER SRN
SASKATCHEWAN AND NE MT. THIS SHORTWAVE HAS AIDED IN THE DEVELOPMENT
OF AN MCS WHICH HAS ENVELOPED MUCH OF THE ERN HALF OF SD EARLY THIS
MORNING IN AN ENVIRONMENT OF HIGH MUCAPE...STRONG 850-700 MB
MOISTURE TRANSPORT AND STRONG DEEP LAYER SHEAR. OVER UPPER MI THE
WEATHER IS MUCH QUIETER AND GENERALLY PCPN FREE UNDER SFC HIGH PRES
RIDGE. AREAS OF FOG HAVE DEVELOPED ESPECIALLY OVER THE ERN HALF OF
THE CWA AND OVER LAKE MI AS HIGHER DEWPOINTS IN THE MID TO UPPER 50S
CONTINUE TO ADVECT NORTHWARD AHEAD OF THE SYSTEM APPROACHING FM THE
NRN PLAINS.
TODAY...LATEST 03Z SREF ENSEMBLE DATA ALONG WITH MAJORITY OF 00Z AND
06Z OPERATIONAL MODEL RUNS INDICATE THE MCS OVER SD WILL CONTINUE TO
TRACK ESE INTO SRN MN AND THE SRN HALF OF WI THIS MORNING INTO EARLY
AFTERNOON FOLLOWING THE GRADIENT OF HIGHEST MLCAPE/MUCAPES IN EXCESS
OF 2000 J/KG. CONTINUED TO FOLLOW PREV FCST SHIFT WITH SLOWER PCPN
ARRIVAL BACKING OFF PCPN TIMING/POPS INTO WRN UPPER MI UNTIL LATE
MORNING AND INTO CENTRAL UPPER MI EARLY/MID AFTERNOON WHEN DEEP
LAYER Q-VECT CONV AND MID-LVL MOISTURE ARRIVES AHEAD OF THE NRN
PLAINS SHORTWAVE ALONG WITH STRONG ISENTROPIC ASCENT AT THE NOSE OF
THE IMPINGING 30-40 KT LOW-LVL JET. INCREASING CONVECTIVE CLOUD
DEBRIS SPREADING IN AHEAD OF MCS TO THE SW WILL TEND TO LIMIT
EXTREME INSTABILITY FROM REACHING FAR NORTH INTO UPPER MI.
HOWEVER...IF ENOUGH CLEARING/HEATING DEVELOPS IN THE AFTERNOON
BEHIND THE INITIAL BATCH OF CONVECTIVE DEBRIS OR LIGHT RAIN TO BOOST
TEMPS TO THE MID 70S AND CAPES TO AROUND 1K J/KG...SEVERE TSRA WILL
BE POSSIBLE AS THE SHORTWAVE AND SFC TROUGH APPROACH. LARGE 0-6KM/0-
1KM SHEAR VALUE OF 55-70KT/30-40KT AND LARGE HELICITY VALUES WILL
SUPPORT THE POTENTIAL FOR SUPERCELL DEVELOPMENT THAT COULD
EVOLVE/ORGANIZE INTO SEVERE STORM CLUSTERS OR AN MCS. DAMAGING
WINDS...LARGE HAIL AND EVEN A TORNADO WOULD BE POSSIBLE MAINLY OVER
THE FAR SCNTRL FCST AREA...CLOSER TO THE HIGHER INSTABILITY GRADIENT
TO THE SOUTH.
TONIGHT...MAY SEE SOME LIGHT RAIN SHOWERS/DRIZZLE OVER FAR ERN UPPER
MI DOWNWIND OF LAKE SUPERIOR AS A POTENT SYSTEM MOVES EAST OUT OF
THE AREA. OTHERWISE...SFC HIGH PRESSURE MOVING INTO THE REGION WILL
LEAD TO CLEARING SKIES LATE TONIGHT WITH GUSTY NW WINDS ON THE
BACKSIDE OF THE SYSTEM. THE STRONG WINDS POSSIBLY REACHING 40 MPH
NEAR THE LAKE SUPERIOR SHORELINE FROM PICTURED ROCKS EASTWARD COULD
LEAD TO MINOR BEACH EROSION.
.LONG TERM...(TUESDAY NIGHT THROUGH MONDAY)
ISSUED AT 325 PM EDT MON JUN 22 2015
SEVERAL SHORTWAVES WILL AFFECT THE UPPER GREAT LAKES REGION THROUGH
THE REST OF THE WORK WEEK AND INTO THE WEEKEND...WHICH WILL SLOWLY
DEVELOP AN UPPER TROUGH OVER THE GREAT LAKES REGION THIS WEEKEND.
ONCE THE UPPER TROUGH BECOMES ESTABLISHED IN THE GREAT LAKES
REGION...ECMWF/GFS ENSEMBLES ARE CONSISTENT ON THE UPPER RIDGE
DEVELOPING OVER THE PACIFIC NORTHWEST THIS WEEKEND TO SLOWLY SHIFT
TO THE NORTHWEST AND REMAIN IN PLACE THROUGH THE FIRST WEEK OF
JULY. THAT WILL LEAD TO A PERSISTENT PERIOD OF NORMAL TO BELOW
NORMAL TEMPERATURES FOR THE GREAT LAKES REGION.
SHIFTING BACK TO THIS WEEK...THE FIRST WAVE THAT WILL AFFECT THE
CWA WILL BE MOVING ACROSS FAR NORTHERN ONTARIO ON TUESDAY
NIGHT...WITH SOUTHWESTERN EDGE OF THAT WAVE BRUSHING THE NORTHEAST
PART OF LAKE SUPERIOR. AT THE SURFACE...A WEAK TROUGH WILL BE
MOVING ACROSS THE LAKE AND EXPECT THERE TO BE SOME SHOWERS ALONG IT
IN NORTHWEST ONTARIO ON TUESDAY AFTERNOON. BUT WITH THE LOSS OF
DIURNAL HEATING...LIMITED MOISTURE...AND THE BEST FORCING STAYING
WELL TO THE NORTHEAST OF THE CWA...WILL ONLY SHOW SLIGHT CHANCE
POPS MOVING SOUTHEAST ACROSS NORTHEAST LAKE SUPERIOR. DID BRUSH THE
KEWEENAW WITH THOSE SLIGHT CHANCE POPS WITH A DECENT NUMBER OF
MODELS SHOWING A FEW HUNDREDTHS OF QPF. OTHERWISE...EXPECT THE REST
OF THE AREA TO BE PARTLY CLOUDY TO MOSTLY CLEAR ON TUESDAY NIGHT DUE
TO THE RESIDUAL EFFECTS OF THE SLOWLY DEPARTING SURFACE RIDGE.
THAT SURFACE RIDGE WILL STILL BE OVER THE GREAT LAKES REGION ON
WEDNESDAY MORNING...AS THE PARENT HIGH MOVES INTO THE MID ATLANTIC
STATES. BUT THE NEXT SHORTWAVE WILL BE QUICKLY APPROACHING THE AREA
ON WEDNESDAY AFTERNOON. MODELS CONTINUE TO DEPICT LINGERING
MOISTURE ASSOCIATED WITH THE TUESDAY NIGHT SURFACE TROUGH BEING
OVER THE U.P. ON WEDNESDAY AFTERNOON AND THAT WILL COMBINE WITH THE
ARRIVAL OF ADDITIONAL MOISTURE/FORCING AND LAKE BREEZE DEVELOPMENT
TO LEAD TO SHOWERS AND A FEW THUNDERSTORMS OVER PORTIONS OF
WEST/CENTRAL UPPER MICHIGAN. WILL CONTINUE TO SHOW THE BEST CHANCE
FOR SHOWERS OVER THE LAND AREAS AND INLAND FROM THE GREAT
LAKES...WITH THE BEST OPPORTUNITY ALONG THE EXPECTED LAKE BREEZE
FROM CENTRAL MARQUETTE COUNTY WESTWARD TOWARDS ONTONAGON COUNTY.
WILL CONTINUE TO KEEP THUNDER VALUES IN THE SLIGHT CHANCE CATEGORY
WITH MLCAPE VALUES GENERALLY UNDER 500J/KG (BEST INSTABILITY WELL
TO THE SOUTH AND TIED TO THE STRONG STORMS LIKELY MOVING THROUGH
SOUTHERN MINNESOTA/WISCONSIN LATE WEDNESDAY AFTERNOON/NIGHT). 0-6KM
BULK SHEAR VALUES LOOK FAIRLY STRONG (APPROACHING 50KTS)...BUT
LOOKING AT THE SOUNDINGS...THAT IS ALL TIED TO THE STRONG JET
BETWEEN 5-6KM. THUS...THINK THE EFFECTIVE SHEAR VALUES AROUND 20KTS
ARE MORE REASONABLE AND BELIEVE THE POTENTIAL FOR STRONG STORMS IS
LIMITED AT THIS POINT. THE ONLY CONCERN WOULD BE WITH THE SLOW STORM
MOTIONS LEADING TO LOCALIZED HEAVY RAIN WHERE THE THUNDERSTORMS
OCCUR.
WHILE THAT FIRST WAVE WILL AFFECT THE AREA WEDNESDAY
AFTERNOON/EVENING...THERE ARE SEVERAL WEAK WAVES TRAILING IT THAT
WILL HAVE AN INFLUENCE ON THE WEATHER FOR THE U.P. THROUGH THURSDAY
NIGHT. WILL SHOW CHANCE POPS AS THESE DISTURBANCES MOVE THROUGH AND
CONTINUE SLIGHT CHANCE FOR THUNDER (ALTHOUGH THAT APPEARS TO BE
FAIRLY OPTIMISTIC). THOSE WAVES WILL AMPLIFY AN UPPER TROUGH OVER
THE GREAT LAKES REGION THIS WEEKEND AND LIKELY CONTINUE INTO EARLY
JULY. THERE IS THE POTENTIAL FOR SOME DIURNAL SHOWERS THIS
WEEKEND...ALTHOUGH THE SUBSIDENCE FROM A HIGH PRESSURE RIDGE MOVING
THROUGH SHOULD LIMIT THE COVERAGE...BEFORE ANOTHER STRONGER WAVE
DROPS SOUTHEAST ACROSS THE AREA ON MONDAY.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON)
ISSUED AT 152 PM EDT MON JUN 22 2015MID/HIGH A LEVEL CLOUDS OVER
THE AREA WILL SUPPRESS CHANCES FOR SHRA/TSRA THIS AFTERNOON.
HOWEVER...SOME HEATING LATE THIS AFTERNOON AHEAD OF A COLD FRONT MAY
STILL BE ENOUGH FOR SOME SHRA/TSRA TO DEVELOP. CONFIDENCE WAS NOT
HIGH ENOUGH THROUGH TO INCLUDE MENTION OF TS. A PERIOD OF MVFR CIGS
IS POSSIBLE ESPECIALLY AT CMX BEHIND THE FRONT...PER UPSTREAM TRENDS.
EXPECT GUSTY WINDS THIS AFTERNOON AHEAD OF THE COLD FRONT AND IN THE
EVENING BEHIND A COLD FRONT AT ALL SITES. WITH DRY ADVECTION BEHIND
THE FRONT EXPECT IMPROVEMENT TO VFR LATE EVENING AND OVERNIGHT.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 515 AM EDT MON JUN 22 2015
A LOW PRES SYSTEM FROM THE NORTHERN PLAINS WILL OVE OVER THE UPPER
GREAT LAKES TODAY INTO THIS EVENING. A TIGHT PRES GRADIENT AND COLD
ADVECTION ON THE BACK SIDE OF THIS LOW WILL SUPPORT A PERIOD OF WNW
35 KNOT GALES LATE TONIGHT INTO TUE MORNING...STRONGEST OVER THE
EAST HALF OF LAKE SUPERIOR. HIGH PRES BUILDING BACK OVER THE AREA
WILL THEN KEEP WINDS LIGHT AGAIN FROM LATE TUE INTO THU.
LINGERING LOW-LVL MOISTURE AND HIGH DEWPOINTS WILL SUPPORT FOG
ACROSS THE LAKE...THAT COULD BE LOCALLY DENSE INTO THIS EVENING.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
GALE WARNING FROM 1 AM TO 10 AM EDT TUESDAY FOR LSZ251-266-267.
LAKE MICHIGAN...
DENSE FOG ADVISORY UNTIL MIDNIGHT EDT TONIGHT FOR LMZ221-248-250.
&&
$$
SHORT TERM...VOSS
LONG TERM...SRF
AVIATION...JLB
MARINE...VOSS
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
153 PM EDT MON JUN 22 2015
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 522 AM EDT MON JUN 22 2015
WV IMAGERY AND RAP ANALYSIS INDICATES A ZONAL PATTERN ACROSS THE NRN
CONUS WITH A WELL-DEFINED SHORTWAVE TROUGH UPSTREAM OVER SRN
SASKATCHEWAN AND NE MT. THIS SHORTWAVE HAS AIDED IN THE DEVELOPMENT
OF AN MCS WHICH HAS ENVELOPED MUCH OF THE ERN HALF OF SD EARLY THIS
MORNING IN AN ENVIRONMENT OF HIGH MUCAPE...STRONG 850-700 MB
MOISTURE TRANSPORT AND STRONG DEEP LAYER SHEAR. OVER UPPER MI THE
WEATHER IS MUCH QUIETER AND GENERALLY PCPN FREE UNDER SFC HIGH PRES
RIDGE. AREAS OF FOG HAVE DEVELOPED ESPECIALLY OVER THE ERN HALF OF
THE CWA AND OVER LAKE MI AS HIGHER DEWPOINTS IN THE MID TO UPPER 50S
CONTINUE TO ADVECT NORTHWARD AHEAD OF THE SYSTEM APPROACHING FM THE
NRN PLAINS.
TODAY...LATEST 03Z SREF ENSEMBLE DATA ALONG WITH MAJORITY OF 00Z AND
06Z OPERATIONAL MODEL RUNS INDICATE THE MCS OVER SD WILL CONTINUE TO
TRACK ESE INTO SRN MN AND THE SRN HALF OF WI THIS MORNING INTO EARLY
AFTERNOON FOLLOWING THE GRADIENT OF HIGHEST MLCAPE/MUCAPES IN EXCESS
OF 2000 J/KG. CONTINUED TO FOLLOW PREV FCST SHIFT WITH SLOWER PCPN
ARRIVAL BACKING OFF PCPN TIMING/POPS INTO WRN UPPER MI UNTIL LATE
MORNING AND INTO CENTRAL UPPER MI EARLY/MID AFTERNOON WHEN DEEP
LAYER Q-VECT CONV AND MID-LVL MOISTURE ARRIVES AHEAD OF THE NRN
PLAINS SHORTWAVE ALONG WITH STRONG ISENTROPIC ASCENT AT THE NOSE OF
THE IMPINGING 30-40 KT LOW-LVL JET. INCREASING CONVECTIVE CLOUD
DEBRIS SPREADING IN AHEAD OF MCS TO THE SW WILL TEND TO LIMIT
EXTREME INSTABILITY FROM REACHING FAR NORTH INTO UPPER MI.
HOWEVER...IF ENOUGH CLEARING/HEATING DEVELOPS IN THE AFTERNOON
BEHIND THE INITIAL BATCH OF CONVECTIVE DEBRIS OR LIGHT RAIN TO BOOST
TEMPS TO THE MID 70S AND CAPES TO AROUND 1K J/KG...SEVERE TSRA WILL
BE POSSIBLE AS THE SHORTWAVE AND SFC TROUGH APPROACH. LARGE 0-6KM/0-
1KM SHEAR VALUE OF 55-70KT/30-40KT AND LARGE HELICITY VALUES WILL
SUPPORT THE POTENTIAL FOR SUPERCELL DEVELOPMENT THAT COULD
EVOLVE/ORGANIZE INTO SEVERE STORM CLUSTERS OR AN MCS. DAMAGING
WINDS...LARGE HAIL AND EVEN A TORNADO WOULD BE POSSIBLE MAINLY OVER
THE FAR SCNTRL FCST AREA...CLOSER TO THE HIGHER INSTABILITY GRADIENT
TO THE SOUTH.
TONIGHT...MAY SEE SOME LIGHT RAIN SHOWERS/DRIZZLE OVER FAR ERN UPPER
MI DOWNWIND OF LAKE SUPERIOR AS A POTENT SYSTEM MOVES EAST OUT OF
THE AREA. OTHERWISE...SFC HIGH PRESSURE MOVING INTO THE REGION WILL
LEAD TO CLEARING SKIES LATE TONIGHT WITH GUSTY NW WINDS ON THE
BACKSIDE OF THE SYSTEM. THE STRONG WINDS POSSIBLY REACHING 40 MPH
NEAR THE LAKE SUPERIOR SHORELINE FROM PICTURED ROCKS EASTWARD COULD
LEAD TO MINOR BEACH EROSION.
.LONG TERM...(TUESDAY THROUGH SUNDAY)
ISSUED AT 338 AM EDT MON JUN 22 2015
MAY SEE SOME LIGHT RAIN SHOWERS/DRIZZLE OVER FAR ERN UPPER MI
DOWNWIND OF LAKE SUPERIOR AS A POTENT SYSTEM MOVES OUT OF THE AREA.
OTHERWISE...SFC HIGH PRESSURE MOVING INTO THE REGION WILL LEAD TO
CLEARING SKIES. BREEZY CONDITIONS IN THE MORNING WILL DIMINISH
TROUGH THE DAY AS THE PRESSURE GRADIENT WEAKENS. EXPECT HIGH TEMPS
IN THE 60S AND 70S.
COULD SEE SOME LIGHT SHOWERS OVER THE NRN CWA LATE TUE EVENING INTO
TUE NIGHT AS A WEAK SHORTWAVE MOVES DOWN THE NW FLOW. MODELS SHOW
THOSE DIMINISHING AS INSTABILITY WEAKENS LATE IN THE DAY AND ALREADY
LIMITED MOISTURE STAYS OVER THE NRN CWA. WILL CONTINUE SLIGHT CHANCE
TO LOW CHANCE POPS.
NEXT SHORTWAVE MOVES IN AROUND PEAK HEATING WED
AFTERNOON/EVENING...WHICH SHOULD BE ABLE TO GENERATE SHOWERS MAINLY
OVER LAND AREAS. WITH LIMITED INSTABILITY JUST WENT WITH SLIGHT
CHANCES OF THUNDER. TEMPS SHOULD BE SIMILAR TO TUE WITH HIGHS IN THE
60S AND 70S.
NOT REAL SURE ON THE FORECAST FOR WED NIGHT INTO THU NIGHT AS MODEL
VARY ON THE TIMING OF A STRONGER SHORTWAVE. THE ECMWF AND NAM ARE
FASTER THAN THE GFS...RESULTING IN SHOWERS AND POSSIBLY SOME THUNDER
WED NIGHT INTO THU BUT MOSTLY DRY THU NIGHT WHILE THE GFS IS ABOUT
12 HOURS SLOWER.
LOTS OF UNCERTAINTY LOOKING AT THE WEEKEND...ESPECIALLY LATER IN THE
WEEKEND...SO WILL JUST RUN WITH A CONSENSUS BLEND.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON)
ISSUED AT 152 PM EDT MON JUN 22 2015MID/HIGH A LEVEL CLOUDS OVER
THE AREA WILL SUPPRESS CHANCES FOR SHRA/TSRA THIS AFTERNOON.
HOWEVER...SOME HEATING LATE THIS AFTERNOON AHEAD OF A COLD FRONT MAY
STILL BE ENOUGH FOR SOME SHRA/TSRA TO DEVELOP. CONFIDENCE WAS NOT
HIGH ENOUGH THROUGH TO INCLUDE MENTION OF TS. A PERIOD OF MVFR CIGS
IS POSSIBLE ESPECIALLY AT CMX BEHIND THE FRONT...PER UPSTREAM TRENDS.
EXPECT GUSTY WINDS THIS AFTERNOON AHEAD OF THE COLD FRONT AND IN THE
EVENING BEHIND A COLD FRONT AT ALL SITES. WITH DRY ADVECTION BEHIND
THE FRONT EXPECT IMPROVEMENT TO VFR LATE EVENING AND OVERNIGHT.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 515 AM EDT MON JUN 22 2015
A LOW PRES SYSTEM FROM THE NORTHERN PLAINS WILL OVE OVER THE UPPER
GREAT LAKES TODAY INTO THIS EVENING. A TIGHT PRES GRADIENT AND COLD
ADVECTION ON THE BACK SIDE OF THIS LOW WILL SUPPORT A PERIOD OF WNW
35 KNOT GALES LATE TONIGHT INTO TUE MORNING...STRONGEST OVER THE
EAST HALF OF LAKE SUPERIOR. HIGH PRES BUILDING BACK OVER THE AREA
WILL THEN KEEP WINDS LIGHT AGAIN FROM LATE TUE INTO THU.
LINGERING LOW-LVL MOISTURE AND HIGH DEWPOINTS WILL SUPPORT FOG
ACROSS THE LAKE...THAT COULD BE LOCALLY DENSE INTO THIS EVENING.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
GALE WARNING FROM 1 AM TO 10 AM EDT TUESDAY FOR LSZ251-266-267.
LAKE MICHIGAN...
DENSE FOG ADVISORY UNTIL MIDNIGHT EDT TONIGHT FOR LMZ221-248-250.
&&
$$
SHORT TERM...VOSS
LONG TERM...TITUS
AVIATION...JLB
MARINE...VOSS
AREA FORECAST DISCUSSION
NWS GAYLORD MI
148 PM EDT MON JUN 22 2015
.UPDATE...
ISSUED AT 148 PM EDT MON JUN 22 2015
NO HUGE CHANGES TO EARLIER THINKING. HAVE BACKED OFF ON AFTERNOON
POPS NORTH OF M-32...WHICH LOOKS TO BE IN A GAP BETWEEN
CONVECTION. STRONGER TO SVR CELLS THIS AFTERNOON WILL BE MAINLY
DOWNSTATE...WITH THE 1K J/KG MLCAPE PLUME STILL SOUTH OF US-10.
GLADWIN/ARENAC COUNTIES HAVE BEEN INCLUDED IN A SVR T-STORM
WATCH...AS THEY MAY BE GRAZED BY STRONGER CELLS TO THE SOUTH THIS
AFTERNOON.
WILL NEED TO WATCH WAKE LOW WINDS POKING INTO THE DECAYING MCS.
TIGHTEST PRESSURE GRADIENT IS OVER SOUTHERN WI...WHERE SOME
40-45KT NON-TSTORM GUSTS HAVE BEEN OBSERVED. THIS TIGHTER GRADIENT
LOOKS TO ADVANCE ACROSS CENTRAL LOWER MI...WITH BETTER WINDS
FOCUSED JUST SOUTH OF THIS FORECAST AREA.
LATE-DAY POSSIBILITIES FOR SVR STORMS REMAIN UNCERTAIN. AS IS ALL
TOO TYPICAL...CLOUDS/PRECIP ARE GOING TO MAKE IT DIFFICULT TO
RELOAD BEFORE THE COLD FRONT ARRIVES. CLOUD COVER IS THINNING IN
WESTERN WI...SO OUR WINDOW ISN/T COMPLETELY CLOSED...BUT IT
CERTAINLY IS NOT CRANKED WIDE OPEN EITHER.
UPDATE ISSUED AT 937 AM EDT MON JUN 22 2015
UPSTREAM MCS IS CROSSING WESTERN WI/EASTERN MN/ADJOINING AREAS.
NORTHERN MI IS PRESENTLY QUITE COOL/DRY/STABLE. INSTABILITY/
MOISTURE WILL BUBBLE UP IN THE SOUTH HALF OF LOWER MI BEFORE THE
MCS ARRIVES (SURFACE DEW POINTS ARE NEARING 70F IN FAR SOUTHERN
LOWER). BUT IT IS UNLIKELY THAT WE WILL SEE SIGNIFICANT INSTABILITY
BUILD HERE BEFORE THE MCS ARRIVES (DOESN/T HELP THAT WE ARE ABOUT
TO START CLOUDING OVER). SHEAR IS ALSO ONLY JUST STARTING TO
INCREASE AT MIDDAY.
SO SHOWERS/A FEW EMBEDDED TSRA ARE LIKELY MIDDAY INTO MID
AFTERNOON WITH THE INCOMING MCS. BEST CHANCE OF TSRA WILL BE IN
SOUTHERN SECTIONS. A STRAY SVR STORM ISN/T COMPLETELY OUT OF THE
QUESTION...BUT SVR WX WITH THIS PORTION OF THE EVENT IS UNLIKELY.
OUR SVR THREAT LOOKS CONSIDERABLY HIGHER IN THE WAKE OF THIS
MCS...UP UNTIL WHEN THE COLD FRONT PASSES THIS EVENING. OF
COURSE...THIS IS DEPENDENT ON SUBSTANTIAL AND RAPID
DESTABILIZATION LATE THIS AFTERNOON/EARLY THIS EVENING. THE
WINDOW FOR SUCH IS SHORT. BUT THE SURFACE WARM FRONT SHOULD
ROCKET NORTHWARD AS SW 850MB WINDS INCREASE TO 50KT BY EARLY
EVENING. IN PARTICULAR...ANY STORMS THAT FORM NEAR THAT WARM FRONT
(AS THE SPC HRRR WANTS TO DO) COULD POSE THE ENTIRE GAMUT OF SVR
WX THREATS.
&&
.NEAR TERM...(TODAY THROUGH TONIGHT)
ISSUED AT 400 AM EDT MON JUN 22 2015
HIGH IMPACT WEATHER: SEVERE THUNDERSTORMS THIS AFTERNOON AND THIS
EVENING.
...SEVERE STORM POTENTIAL LOOKS BETTER USUAL...
SYNOPTIC PATTERN AND OBSERVATIONS:
EARLY THIS MORNING...PRETTY QUIET OUT THERE THIS MORNING WITH SFC
HIGH PRESSURE AND LIGHT WINDS OVERHEAD. AREAS OF FOG AND STRATUS
FAIRLY WIDESPREAD ACROSS EASTERN UPPER...DEVELOPING OVER PARTS OF
LAKE HURON...AND STRETCHING NORTH ACROSS LAKE MICHIGAN. THIS IS
ASSOCIATED WITH INCREASING LOW LEVEL MOISTURE FROM SOUTHERLY
WINDS. SYNOPTICALLY...A DEVELOPING AND NORTHWARD MOVING WARM FRONT
STRETCHED FROM LOW PRESSURE IN SOUTHERN SD...THROUGH IOWA AND
DOWN ACROSS IL/IN. A COLD FRONT EXTENDED SOUTH OF THE LOW PRESSURE
ACROSS THE WESTERN SD. A STRENGTHENING LOW LEVEL JET WITH THETA-E
ADVECTION IS STRONG INTO SD WHILE CONDITIONS ALOFT ARE IMPRESSIVE.
STEEP 6.5 TO 7.0 C/KM LAPSE RATES...WITH GOOD UPPER LEVEL
DIVERGENCE IN A STRENGTHENING UPPER LEVEL JET AHEAD OF A
SHARPENING SHORTWAVE TROUGH. ONE CONVECTIVE COMPLEX WAS CROSSING
MN WITH AN ASSOCIATED MCV...WHILE STRONGER CONVECTION WAS ACROSS
THE DAKOTAS...MORE SPOTTY STORMS IN IOWA...ALONG THE WARM FRONT.
SYNOPTIC PATTERN EVOLUTION AND ASSOCIATED WEATHER:
HIGH LEVEL CLOUDS WERE NEARING NRN MICHIGAN...AHEAD OF THE MCV AND
SHOWERS IN MN. CLOUDS WILL THICKEN IN THE UPPER LEVELS THROUGH
THE MORNING...DRIVEN BY THE ADVANCING MCV...DESPITE A FAIRLY DRY
00Z APX SOUNDING AND WARMING CLOUD TOPS. MEANWHILE...THE STORMS
FROM SD WILL ADVANCE/DEVELOP FURTHER...INTO SRN MN/IOWA AS THE LLJ
VEERS MORE WEST...AND WHERE THE UPPER DIVERGENCE SIGNATURE SHIFTS.
THIS IS ALSO WHERE THE DEEPER MOISTURE AND INSTABILITY RESIDES...A
MOST COMMON PLACE WHERE OVERNIGHT CONVECTION PROPAGATES INTO. THE
MAIN UPPER TROUGH SHARPENS FURTHER AND CROSSES THROUGH THE GREAT
LAKES TONIGHT...DEEPENING THE SFC LOW PRESSURE...LIFTING IN INTO
ONTARIO. STRONG UPPER LEVEL WINDS WORK IN OVERHEAD...90-100KT
UPPER JET AND DIVERGENCE...AND 35-45KT LLJ POINTING INTO NRN
MICHIGAN. THIS IDEA IS FOR STRONG LOW TO MID LEVEL WAA OVER US
THIS AFTERNOON...WITH THE WARM FRONT MAKING IT UP INTO NRN LOWER
MICHIGAN...WHILE THE COLD FRONT FOLLOWS THIS EVENING AND EXITING
OVERNIGHT. BULK SHEAR VALUES ARE INCREDIBLE AT 60+ KTS WITH STEEP
LAPSE RATES AND INCREASED LOW LEVEL HELICITIES TO 300+ M2/S2 WITH
THE WARM FRONT. REALLY STILL TOO EARLY TO SEE HOW THE CLOUD COVER
SITUATION...AND THE WARM FRONTAL CONVECTIVE SCENARIO WILL PLAY
OUT...AND THUS...HOW BELIEVABLE THAT THE WARM FRONT MAKES IT UP
HERE. THIS ALSO PLAYS INTO HOW MUCH INSTABILITY WE CAN GENERATE.
THE SHORTWAVE COULD CONCEIVABLY FORCE FEED THE WARM FRONT UP
HERE...BUT WE WILL REALLY BE NEEDING THE MORNING WARM FRONTAL
STORMS/CLOUDS/PRECIP TO NOT STALL THE FRONT WELL TO OUR SOUTH.
RIGHT NOW...THIS IS NOT THE CASE WITH JUST SOME SPOTTY CONVECTION
OVER IOWA...AND THE BULK OF THE STORMS WELL WEST OF HERE. SO...AM
STILL GOING TO LEAN TO THE IDEA OF SURFACE BASED HEATING AND A
JUMP OF THE WARM FRONT INTO NRN MICHIGAN. THIS GENERATES 1000-2000
J/KG...ABLE TO TAP INTO THE STRONG WINDS ALOFT FOR A DAMAGING WIND
THREAT. STRONGER UPDRAFTS COULD ALSO RESULT IN LARGE HAIL...AND
THE HIGH HELICITIES WITH THE WARM FRONT ALSO PROMOTES POTENTIAL
TORNADOS. THIS SET UP LOOKS BETTER THAN MOST TIMES AROUND NRN
MICHIGAN. IF IT IS TO OCCUR...THOSE CLOUDS CANNOT PUT A LID ON SFC
HEATING...AND AGAIN...DONT THINK THAT WILL HAPPEN (FOR NOW).
NRN MICHIGAN FOLKS NEED TO BE AWARE OF THIS POTENTIALLY VOLATILE
SEVERE WEATHER SET UP...AND REMAIN ALERT TO THE DEVELOPING WEATHER
THROUGH THE DAY. SPC DAY 1 OUTLOOK HAS NRN MICHIGAN IN A SLIGHT
RISK EVERYWHERE...WITH AN ENHANCED SEVERE CHANCE ALONG AND SOUTH
OF M-72. THE COLD FRONT PASSES OVERNIGHT AND COLDER/DRIER AIR
SWEEPS IN...ENDING THE SHOWERS/STORMS.
&&
.SHORT TERM...(TUESDAY THROUGH WEDNESDAY NIGHT)
ISSUED AT 400 AM EDT MON JUN 22 2015
NEARLY ZONAL FLOW FOR THE REMAINDER OF THE WEEK. INCREASING RIDGING
(AND TRIPLE DIGIT HEAT) ALONG THE WEST COAST SHOULD EVENTUALLY
DEEPEN A TROUGH ACROSS THE GREAT LAKES...BUT THIS MAY NOT OCCUR
UNTIL EARLY NEXT WEEK. THE MAIN SHORT TERM FORECAST CONCERNS ARE THE
TIMING OF POSSIBLE POPS AND THE POTENTIAL FOR THUNDERSTORMS
WEDNESDAY NIGHT.
TUESDAY INTO TUESDAY NIGHT...WITH THE EXCEPTION OF POSSIBLE STRATUS
TO START OFF THE DAY...HIGH PRESSURE AT THE SURFACE AND SUBTLE
HEIGHT RISES SHOULD LEAD TO CLEARING SKIES AND SLIGHTLY LESS MUGGY
CONDITIONS. HIGHS GENERALLY IN THE UPPER 60S TO MIDDLE 70S WITH LOWS
RANGING FROM THE MORE COMFORTABLE UPPER 40S NORTH TO THE MIDDLE 50S
SOUTH.
WEDNESDAY INTO WEDNESDAY NIGHT...HIGH PRESSURE MOVES OFF TO THE EAST
ALLOWING FOR SLOWLY INCREASING MOISTURE (PW/S RISING TO NEAR 1.25
INCHES BY 12Z THU). MEANWHILE...A WEAK SHORT WAVE MOVING THROUGH THE
FLOW WILL BRING CHANCES FOR SHOWERS AND POSSIBLE THUNDERSTORMS
WEDNESDAY NIGHT (THOUGH INSTABILITY LOOKS ON THE MEAGER SIDE). HIGHS
RANGING FROM THE LOWER 70S NORTH TO THE UPPER 70S SOUTH. LOWS IN THE
MILDER MIDDLE 50S TO AROUND 60.
&&
.LONG TERM...(THURSDAY THROUGH SUNDAY)
ISSUED AT 400 AM EDT MON JUN 22 2015
A SHORT WAVE MOVING THROUGH THE FLOW WILL BRING CONTINUED CHANCES
FOR SHOWERS AND THUNDERSTORMS THURSDAY. NORTHERN MICHIGAN THEN ENDS
UP BETWEEN JET STREAMS AFTER THAT (WITH ENERGY MOVING BY TO THE
NORTH AND SOUTH) SO ONLY SLIGHT OR LOWER END CHANCES FOR SHOWERS ARE
EXPECTED FOR THE REMAINDER OF THE PERIOD. MODELS ARE THEN HINTING AT
POSSIBLE DEEPER TROUGHING NEXT WEEK AS THE HEAT BUILDS OUT WEST.
TEMPERATURES WILL REMAIN NEAR TO SLIGHTLY BELOW AVERAGE FOR LATER
JUNE.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON)
ISSUED AT 148 PM EDT MON JUN 22 2015
SHRA/PERHAPS TSRA THIS AFTERNOON. TSRA LIKELY THIS EVENING.
COLD FRONT WILL CROSS NORTHERN MI LATE THIS EVENING. INITIAL ROUND
OF SHRA/TSRA ENTERING LOWER MI...WITH STRONGER TSRA LARGELY
EXPECTED TO STAY TO OUR SOUTH THIS AFTERNOON. SOME THREAT FOR
BRIEF MVFR CONDITIONS. STRONGER TSRA POSSIBLE FOR THIS EVENING
WITH THE COLD FRONT...THOUGH THIS IS NOT CERTAIN GIVEN POTENTIAL
LACK OF INSTABILITY. GUSTY WINDS CERTAINLY POSSIBLE WITH EVENING
TSRA...AND BRIEF MVFR/IFR CONDITIONS. WE WILL DRY OUT OVERNIGHT
INTO TUESDAY MORNING BEHIND THE FRONT.
SOUTHERLY WINDS THIS AFTERNOON...GUSTY AT TIMES. WINDS VEERING W
AND NW OVERNIGHT AND TUESDAY...GUSTY TUESDAY.
&&
.MARINE...
ISSUED AT 400 AM EDT MON JUN 22 2015
SFC HIGH PRESSURE SHIFTS EAST TODAY WHILE LOW PRESSURE LIFTS
THROUGH THE ARROWHEAD...AND THEN ACROSS ONTARIO TONIGHT. LIGHT
WINDS SHIFT OUT OF THE SOUTH/SE AND INCREASE TO SOLID ADVISORY
LEVELS THROUGH TONIGHT...AND THROUGH TUESDAY FOR MOST NEARSHORES.
HIGH PRESSURE SETTLES BACK IN FOR WEDNESDAY WITH LIGHT WINDS.
MORE CONCERNING IS THE POTENTIAL FOR SHOWERS AND SEVERE
THUNDERSTORMS THIS AFTERNOON AND THIS EVENING...ASSOCIATED WITH A
WARM FRONT (THIS AFTERNOON) AND A FOLLOWING COLD FRONT (THIS
EVENING). AREAS OF FOG WILL ALSO BE COMMON ACROSS THE LAKES.
THE MAIN THREAT WILL BE DAMAGING WINDS...BUT HAIL IS ALSO
EXPECTED.
&&
.APX WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LH...SMALL CRAFT ADVISORY FROM 5 PM THIS AFTERNOON TO 5 PM EDT
TUESDAY FOR LHZ345>349.
LM...SMALL CRAFT ADVISORY FROM 5 PM THIS AFTERNOON TO 5 PM EDT
TUESDAY FOR LMZ341-342.
SMALL CRAFT ADVISORY UNTIL 8 AM EDT TUESDAY FOR LMZ323-344>346.
LS...SMALL CRAFT ADVISORY FROM 5 PM THIS AFTERNOON TO 5 PM EDT
TUESDAY FOR LSZ321-322.
&&
$$
UPDATE...JAZ
NEAR TERM...SMD
SHORT TERM...SULLIVAN
LONG TERM...SULLIVAN
AVIATION...JAZ
MARINE...SMD
AREA FORECAST DISCUSSION
NWS GAYLORD MI
937 AM EDT MON JUN 22 2015
.UPDATE...
ISSUED AT 937 AM EDT MON JUN 22 2015
UPSTREAM MCS IS CROSSING WESTERN WI/EASTERN MN/ADJOINING AREAS.
NORTHERN MI IS PRESENTLY QUITE COOL/DRY/STABLE. INSTABILITY/
MOISTURE WILL BUBBLE UP IN THE SOUTH HALF OF LOWER MI BEFORE THE
MCS ARRIVES (SURFACE DEW POINTS ARE NEARING 70F IN FAR SOUTHERN
LOWER). BUT IT IS UNLIKELY THAT WE WILL SEE SIGNIFICANT INSTABILITY
BUILD HERE BEFORE THE MCS ARRIVES (DOESN/T HELP THAT WE ARE ABOUT
TO START CLOUDING OVER). SHEAR IS ALSO ONLY JUST STARTING TO
INCREASE AT MIDDAY.
SO SHOWERS/A FEW EMBEDDED TSRA ARE LIKELY MIDDAY INTO MID
AFTERNOON WITH THE INCOMING MCS. BEST CHANCE OF TSRA WILL BE IN
SOUTHERN SECTIONS. A STRAY SVR STORM ISN/T COMPLETELY OUT OF THE
QUESTION...BUT SVR WX WITH THIS PORTION OF THE EVENT IS UNLIKELY.
OUR SVR THREAT LOOKS CONSIDERABLY HIGHER IN THE WAKE OF THIS
MCS...UP UNTIL WHEN THE COLD FRONT PASSES THIS EVENING. OF
COURSE...THIS IS DEPENDENT ON SUBSTANTIAL AND RAPID
DESTABILIZATION LATE THIS AFTERNOON/EARLY THIS EVENING. THE
WINDOW FOR SUCH IS SHORT. BUT THE SURFACE WARM FRONT SHOULD
ROCKET NORTHWARD AS SW 850MB WINDS INCREASE TO 50KT BY EARLY
EVENING. IN PARTICULAR...ANY STORMS THAT FORM NEAR THAT WARM FRONT
(AS THE SPC HRRR WANTS TO DO) COULD POSE THE ENTIRE GAMUT OF SVR
WX THREATS.
&&
.NEAR TERM...(TODAY THROUGH TONIGHT)
ISSUED AT 400 AM EDT MON JUN 22 2015
HIGH IMPACT WEATHER: SEVERE THUNDERSTORMS THIS AFTERNOON AND THIS
EVENING.
...SEVERE STORM POTENTIAL LOOKS BETTER USUAL...
SYNOPTIC PATTERN AND OBSERVATIONS:
EARLY THIS MORNING...PRETTY QUIET OUT THERE THIS MORNING WITH SFC
HIGH PRESSURE AND LIGHT WINDS OVERHEAD. AREAS OF FOG AND STRATUS
FAIRLY WIDESPREAD ACROSS EASTERN UPPER...DEVELOPING OVER PARTS OF
LAKE HURON...AND STRETCHING NORTH ACROSS LAKE MICHIGAN. THIS IS
ASSOCIATED WITH INCREASING LOW LEVEL MOISTURE FROM SOUTHERLY
WINDS. SYNOPTICALLY...A DEVELOPING AND NORTHWARD MOVING WARM FRONT
STRETCHED FROM LOW PRESSURE IN SOUTHERN SD...THROUGH IOWA AND
DOWN ACROSS IL/IN. A COLD FRONT EXTENDED SOUTH OF THE LOW PRESSURE
ACROSS THE WESTERN SD. A STRENGTHENING LOW LEVEL JET WITH THETA-E
ADVECTION IS STRONG INTO SD WHILE CONDITIONS ALOFT ARE IMPRESSIVE.
STEEP 6.5 TO 7.0 C/KM LAPSE RATES...WITH GOOD UPPER LEVEL
DIVERGENCE IN A STRENGTHENING UPPER LEVEL JET AHEAD OF A
SHARPENING SHORTWAVE TROUGH. ONE CONVECTIVE COMPLEX WAS CROSSING
MN WITH AN ASSOCIATED MCV...WHILE STRONGER CONVECTION WAS ACROSS
THE DAKOTAS...MORE SPOTTY STORMS IN IOWA...ALONG THE WARM FRONT.
SYNOPTIC PATTERN EVOLUTION AND ASSOCIATED WEATHER:
HIGH LEVEL CLOUDS WERE NEARING NRN MICHIGAN...AHEAD OF THE MCV AND
SHOWERS IN MN. CLOUDS WILL THICKEN IN THE UPPER LEVELS THROUGH
THE MORNING...DRIVEN BY THE ADVANCING MCV...DESPITE A FAIRLY DRY
00Z APX SOUNDING AND WARMING CLOUD TOPS. MEANWHILE...THE STORMS
FROM SD WILL ADVANCE/DEVELOP FURTHER...INTO SRN MN/IOWA AS THE LLJ
VEERS MORE WEST...AND WHERE THE UPPER DIVERGENCE SIGNATURE SHIFTS.
THIS IS ALSO WHERE THE DEEPER MOISTURE AND INSTABILITY RESIDES...A
MOST COMMON PLACE WHERE OVERNIGHT CONVECTION PROPAGATES INTO. THE
MAIN UPPER TROUGH SHARPENS FURTHER AND CROSSES THROUGH THE GREAT
LAKES TONIGHT...DEEPENING THE SFC LOW PRESSURE...LIFTING IN INTO
ONTARIO. STRONG UPPER LEVEL WINDS WORK IN OVERHEAD...90-100KT
UPPER JET AND DIVERGENCE...AND 35-45KT LLJ POINTING INTO NRN
MICHIGAN. THIS IDEA IS FOR STRONG LOW TO MID LEVEL WAA OVER US
THIS AFTERNOON...WITH THE WARM FRONT MAKING IT UP INTO NRN LOWER
MICHIGAN...WHILE THE COLD FRONT FOLLOWS THIS EVENING AND EXITING
OVERNIGHT. BULK SHEAR VALUES ARE INCREDIBLE AT 60+ KTS WITH STEEP
LAPSE RATES AND INCREASED LOW LEVEL HELICITIES TO 300+ M2/S2 WITH
THE WARM FRONT. REALLY STILL TOO EARLY TO SEE HOW THE CLOUD COVER
SITUATION...AND THE WARM FRONTAL CONVECTIVE SCENARIO WILL PLAY
OUT...AND THUS...HOW BELIEVABLE THAT THE WARM FRONT MAKES IT UP
HERE. THIS ALSO PLAYS INTO HOW MUCH INSTABILITY WE CAN GENERATE.
THE SHORTWAVE COULD CONCEIVABLY FORCE FEED THE WARM FRONT UP
HERE...BUT WE WILL REALLY BE NEEDING THE MORNING WARM FRONTAL
STORMS/CLOUDS/PRECIP TO NOT STALL THE FRONT WELL TO OUR SOUTH.
RIGHT NOW...THIS IS NOT THE CASE WITH JUST SOME SPOTTY CONVECTION
OVER IOWA...AND THE BULK OF THE STORMS WELL WEST OF HERE. SO...AM
STILL GOING TO LEAN TO THE IDEA OF SURFACE BASED HEATING AND A
JUMP OF THE WARM FRONT INTO NRN MICHIGAN. THIS GENERATES 1000-2000
J/KG...ABLE TO TAP INTO THE STRONG WINDS ALOFT FOR A DAMAGING WIND
THREAT. STRONGER UPDRAFTS COULD ALSO RESULT IN LARGE HAIL...AND
THE HIGH HELICITIES WITH THE WARM FRONT ALSO PROMOTES POTENTIAL
TORNADOS. THIS SET UP LOOKS BETTER THAN MOST TIMES AROUND NRN
MICHIGAN. IF IT IS TO OCCUR...THOSE CLOUDS CANNOT PUT A LID ON SFC
HEATING...AND AGAIN...DONT THINK THAT WILL HAPPEN (FOR NOW).
NRN MICHIGAN FOLKS NEED TO BE AWARE OF THIS POTENTIALLY VOLATILE
SEVERE WEATHER SET UP...AND REMAIN ALERT TO THE DEVELOPING WEATHER
THROUGH THE DAY. SPC DAY 1 OUTLOOK HAS NRN MICHIGAN IN A SLIGHT
RISK EVERYWHERE...WITH AN ENHANCED SEVERE CHANCE ALONG AND SOUTH
OF M-72. THE COLD FRONT PASSES OVERNIGHT AND COLDER/DRIER AIR
SWEEPS IN...ENDING THE SHOWERS/STORMS.
&&
.SHORT TERM...(TUESDAY THROUGH WEDNESDAY NIGHT)
ISSUED AT 400 AM EDT MON JUN 22 2015
NEARLY ZONAL FLOW FOR THE REMAINDER OF THE WEEK. INCREASING RIDGING
(AND TRIPLE DIGIT HEAT) ALONG THE WEST COAST SHOULD EVENTUALLY
DEEPEN A TROUGH ACROSS THE GREAT LAKES...BUT THIS MAY NOT OCCUR
UNTIL EARLY NEXT WEEK. THE MAIN SHORT TERM FORECAST CONCERNS ARE THE
TIMING OF POSSIBLE POPS AND THE POTENTIAL FOR THUNDERSTORMS
WEDNESDAY NIGHT.
TUESDAY INTO TUESDAY NIGHT...WITH THE EXCEPTION OF POSSIBLE STRATUS
TO START OFF THE DAY...HIGH PRESSURE AT THE SURFACE AND SUBTLE
HEIGHT RISES SHOULD LEAD TO CLEARING SKIES AND SLIGHTLY LESS MUGGY
CONDITIONS. HIGHS GENERALLY IN THE UPPER 60S TO MIDDLE 70S WITH LOWS
RANGING FROM THE MORE COMFORTABLE UPPER 40S NORTH TO THE MIDDLE 50S
SOUTH.
WEDNESDAY INTO WEDNESDAY NIGHT...HIGH PRESSURE MOVES OFF TO THE EAST
ALLOWING FOR SLOWLY INCREASING MOISTURE (PW/S RISING TO NEAR 1.25
INCHES BY 12Z THU). MEANWHILE...A WEAK SHORT WAVE MOVING THROUGH THE
FLOW WILL BRING CHANCES FOR SHOWERS AND POSSIBLE THUNDERSTORMS
WEDNESDAY NIGHT (THOUGH INSTABILITY LOOKS ON THE MEAGER SIDE). HIGHS
RANGING FROM THE LOWER 70S NORTH TO THE UPPER 70S SOUTH. LOWS IN THE
MILDER MIDDLE 50S TO AROUND 60.
&&
.LONG TERM...(THURSDAY THROUGH SUNDAY)
ISSUED AT 400 AM EDT MON JUN 22 2015
A SHORT WAVE MOVING THROUGH THE FLOW WILL BRING CONTINUED CHANCES
FOR SHOWERS AND THUNDERSTORMS THURSDAY. NORTHERN MICHIGAN THEN ENDS
UP BETWEEN JET STREAMS AFTER THAT (WITH ENERGY MOVING BY TO THE
NORTH AND SOUTH) SO ONLY SLIGHT OR LOWER END CHANCES FOR SHOWERS ARE
EXPECTED FOR THE REMAINDER OF THE PERIOD. MODELS ARE THEN HINTING AT
POSSIBLE DEEPER TROUGHING NEXT WEEK AS THE HEAT BUILDS OUT WEST.
TEMPERATURES WILL REMAIN NEAR TO SLIGHTLY BELOW AVERAGE FOR LATER
JUNE.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z TUESDAY MORNING)
ISSUED AT 713 AM EDT MON JUN 22 2015
FOG/STRATUS WILL MIX OUT QUICKLY THIS MORNING. BIG ISSUE IS FOR
SHOWERS AND THUNDERSTORMS THIS AFTERNOON AND EVENING AS A WARM
FRONT LIFTS INTO THE REGION...WHICH WILL BE FOLLOWED BY A COLD
FRONT IN THE EVENING. VERY IMPRESSIVE WIND FIELDS AND POTENTIAL
STORM ORGANIZATION FOR SEVERE WEATHER. WIND/HAIL AND TORNADOS ARE
ALL POSSIBLE PROVIDED WE CAN GET UNSTABLE TODAY WITH DAYTIME
HEATING/SUN. ALL OF THIS PREDICATED UPON SHOWER AND STORM
EVOLUTION ACROSS SRN MN/NE IOWA (WHETHER THIS AND OTHER STORM
DEVELOPMENT THERE WILL BRING IN CLOUDS AND A SUBSEQUENT LESS
UNSTABLE SCENARIO BY KEEPING THE WARM FRONT SOUTH OF US). BIGGEST
THREAT FOR SEVERE WEATHER IS LIKELY THIS EVENING...WITH STRONGEST
WIND FIELDS AND DAMAGING WIND THREAT AHEAD OF APPROACHING COLD
FRONT. ANY SHOWERS/STORMS ARE LIKELY EXIT AROUND/SHORTLY AFTER
MIDNIGHT.
&&
.MARINE...
ISSUED AT 400 AM EDT MON JUN 22 2015
SFC HIGH PRESSURE SHIFTS EAST TODAY WHILE LOW PRESSURE LIFTS
THROUGH THE ARROWHEAD...AND THEN ACROSS ONTARIO TONIGHT. LIGHT
WINDS SHIFT OUT OF THE SOUTH/SE AND INCREASE TO SOLID ADVISORY
LEVELS THROUGH TONIGHT...AND THROUGH TUESDAY FOR MOST NEARSHORES.
HIGH PRESSURE SETTLES BACK IN FOR WEDNESDAY WITH LIGHT WINDS.
MORE CONCERNING IS THE POTENTIAL FOR SHOWERS AND SEVERE
THUNDERSTORMS THIS AFTERNOON AND THIS EVENING...ASSOCIATED WITH A
WARM FRONT (THIS AFTERNOON) AND A FOLLOWING COLD FRONT (THIS
EVENING). AREAS OF FOG WILL ALSO BE COMMON ACROSS THE LAKES.
THE MAIN THREAT WILL BE DAMAGING WINDS...BUT HAIL IS ALSO
EXPECTED.
&&
.APX WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LH...SMALL CRAFT ADVISORY FROM 5 PM THIS AFTERNOON TO 5 PM EDT
TUESDAY FOR LHZ345>349.
LM...SMALL CRAFT ADVISORY FROM 5 PM THIS AFTERNOON TO 5 PM EDT
TUESDAY FOR LMZ341-342.
SMALL CRAFT ADVISORY FROM 2 PM THIS AFTERNOON TO 8 AM EDT
TUESDAY FOR LMZ323-344>346.
LS...SMALL CRAFT ADVISORY FROM 5 PM THIS AFTERNOON TO 5 PM EDT
TUESDAY FOR LSZ321-322.
&&
$$
UPDATE...JAZ
NEAR TERM...SMD
SHORT TERM...SULLIVAN
LONG TERM...SULLIVAN
AVIATION...SMD
MARINE...SMD
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
749 AM EDT MON JUN 22 2015
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 522 AM EDT MON JUN 22 2015
WV IMAGERY AND RAP ANALYSIS INDICATES A ZONAL PATTERN ACROSS THE NRN
CONUS WITH A WELL-DEFINED SHORTWAVE TROUGH UPSTREAM OVER SRN
SASKATCHEWAN AND NE MT. THIS SHORTWAVE HAS AIDED IN THE DEVELOPMENT
OF AN MCS WHICH HAS ENVELOPED MUCH OF THE ERN HALF OF SD EARLY THIS
MORNING IN AN ENVIRONMENT OF HIGH MUCAPE...STRONG 850-700 MB
MOISTURE TRANSPORT AND STRONG DEEP LAYER SHEAR. OVER UPPER MI THE
WEATHER IS MUCH QUIETER AND GENERALLY PCPN FREE UNDER SFC HIGH PRES
RIDGE. AREAS OF FOG HAVE DEVELOPED ESPECIALLY OVER THE ERN HALF OF
THE CWA AND OVER LAKE MI AS HIGHER DEWPOINTS IN THE MID TO UPPER 50S
CONTINUE TO ADVECT NORTHWARD AHEAD OF THE SYSTEM APPROACHING FM THE
NRN PLAINS.
TODAY...LATEST 03Z SREF ENSEMBLE DATA ALONG WITH MAJORITY OF 00Z AND
06Z OPERATIONAL MODEL RUNS INDICATE THE MCS OVER SD WILL CONTINUE TO
TRACK ESE INTO SRN MN AND THE SRN HALF OF WI THIS MORNING INTO EARLY
AFTERNOON FOLLOWING THE GRADIENT OF HIGHEST MLCAPE/MUCAPES IN EXCESS
OF 2000 J/KG. CONTINUED TO FOLLOW PREV FCST SHIFT WITH SLOWER PCPN
ARRIVAL BACKING OFF PCPN TIMING/POPS INTO WRN UPPER MI UNTIL LATE
MORNING AND INTO CENTRAL UPPER MI EARLY/MID AFTERNOON WHEN DEEP
LAYER Q-VECT CONV AND MID-LVL MOISTURE ARRIVES AHEAD OF THE NRN
PLAINS SHORTWAVE ALONG WITH STRONG ISENTROPIC ASCENT AT THE NOSE OF
THE IMPINGING 30-40 KT LOW-LVL JET. INCREASING CONVECTIVE CLOUD
DEBRIS SPREADING IN AHEAD OF MCS TO THE SW WILL TEND TO LIMIT
EXTREME INSTABILITY FROM REACHING FAR NORTH INTO UPPER MI.
HOWEVER...IF ENOUGH CLEARING/HEATING DEVELOPS IN THE AFTERNOON
BEHIND THE INITIAL BATCH OF CONVECTIVE DEBRIS OR LIGHT RAIN TO BOOST
TEMPS TO THE MID 70S AND CAPES TO AROUND 1K J/KG...SEVERE TSRA WILL
BE POSSIBLE AS THE SHORTWAVE AND SFC TROUGH APPROACH. LARGE 0-6KM/0-
1KM SHEAR VALUE OF 55-70KT/30-40KT AND LARGE HELICITY VALUES WILL
SUPPORT THE POTENTIAL FOR SUPERCELL DEVELOPMENT THAT COULD
EVOLVE/ORGANIZE INTO SEVERE STORM CLUSTERS OR AN MCS. DAMAGING
WINDS...LARGE HAIL AND EVEN A TORNADO WOULD BE POSSIBLE MAINLY OVER
THE FAR SCNTRL FCST AREA...CLOSER TO THE HIGHER INSTABILITY GRADIENT
TO THE SOUTH.
TONIGHT...MAY SEE SOME LIGHT RAIN SHOWERS/DRIZZLE OVER FAR ERN UPPER
MI DOWNWIND OF LAKE SUPERIOR AS A POTENT SYSTEM MOVES EAST OUT OF
THE AREA. OTHERWISE...SFC HIGH PRESSURE MOVING INTO THE REGION WILL
LEAD TO CLEARING SKIES LATE TONIGHT WITH GUSTY NW WINDS ON THE
BACKSIDE OF THE SYSTEM. THE STRONG WINDS POSSIBLY REACHING 40 MPH
NEAR THE LAKE SUPERIOR SHORELINE FROM PICTURED ROCKS EASTWARD COULD
LEAD TO MINOR BEACH EROSION.
.LONG TERM...(TUESDAY THROUGH SUNDAY)
ISSUED AT 338 AM EDT MON JUN 22 2015
MAY SEE SOME LIGHT RAIN SHOWERS/DRIZZLE OVER FAR ERN UPPER MI
DOWNWIND OF LAKE SUPERIOR AS A POTENT SYSTEM MOVES OUT OF THE AREA.
OTHERWISE...SFC HIGH PRESSURE MOVING INTO THE REGION WILL LEAD TO
CLEARING SKIES. BREEZY CONDITIONS IN THE MORNING WILL DIMINISH
TROUGH THE DAY AS THE PRESSURE GRADIENT WEAKENS. EXPECT HIGH TEMPS
IN THE 60S AND 70S.
COULD SEE SOME LIGHT SHOWERS OVER THE NRN CWA LATE TUE EVENING INTO
TUE NIGHT AS A WEAK SHORTWAVE MOVES DOWN THE NW FLOW. MODELS SHOW
THOSE DIMINISHING AS INSTABILITY WEAKENS LATE IN THE DAY AND ALREADY
LIMITED MOISTURE STAYS OVER THE NRN CWA. WILL CONTINUE SLIGHT CHANCE
TO LOW CHANCE POPS.
NEXT SHORTWAVE MOVES IN AROUND PEAK HEATING WED
AFTERNOON/EVENING...WHICH SHOULD BE ABLE TO GENERATE SHOWERS MAINLY
OVER LAND AREAS. WITH LIMITED INSTABILITY JUST WENT WITH SLIGHT
CHANCES OF THUNDER. TEMPS SHOULD BE SIMILAR TO TUE WITH HIGHS IN THE
60S AND 70S.
NOT REAL SURE ON THE FORECAST FOR WED NIGHT INTO THU NIGHT AS MODEL
VARY ON THE TIMING OF A STRONGER SHORTWAVE. THE ECMWF AND NAM ARE
FASTER THAN THE GFS...RESULTING IN SHOWERS AND POSSIBLY SOME THUNDER
WED NIGHT INTO THU BUT MOSTLY DRY THU NIGHT WHILE THE GFS IS ABOUT
12 HOURS SLOWER.
LOTS OF UNCERTAINTY LOOKING AT THE WEEKEND...ESPECIALLY LATER IN THE
WEEKEND...SO WILL JUST RUN WITH A CONSENSUS BLEND.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z TUESDAY MORNING)
ISSUED AT 744 AM EDT MON JUN 22 2015
VLIFR CONDITIONS IN FOG/STRATUS WILL LIFT AT KSAW BY 14Z...THEN
ACTIVE WEATHER IS EXPECTED WITH HEAVIER RAIN AND MVFR CONDITIONS
ARRIVING THIS AFTERNOON. THERE PROBABLY WILL BE THUNDER AT TIMES
AT KSAW AND KIWD SO INCLUDED VCTS THERE...BUT CONFIDENCE TOO LOW TO
INCLUDE AT KCMX AT THIS TIME. WILL GET GUSTY IN THE AFTERNOON OUT
AHEAD OF A COLD FRONT AND IN THE EVENING BEHIND A COLD FRONT AT ALL
SITES AND CONDITIONS QUICKLY IMPROVE TO VFR.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 515 AM EDT MON JUN 22 2015
A LOW PRES SYSTEM FROM THE NORTHERN PLAINS WILL OVE OVER THE UPPER
GREAT LAKES TODAY INTO THIS EVENING. A TIGHT PRES GRADIENT AND COLD
ADVECTION ON THE BACK SIDE OF THIS LOW WILL SUPPORT A PERIOD OF WNW
35 KNOT GALES LATE TONIGHT INTO TUE MORNING...STRONGEST OVER THE
EAST HALF OF LAKE SUPERIOR. HIGH PRES BUILDING BACK OVER THE AREA
WILL THEN KEEP WINDS LIGHT AGAIN FROM LATE TUE INTO THU.
LINGERING LOW-LVL MOISTURE AND HIGH DEWPOINTS WILL SUPPORT FOG
ACROSS THE LAKE...THAT COULD BE LOCALLY DENSE INTO THIS EVENING.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
GALE WARNING FROM 1 AM TO 10 AM EDT TUESDAY FOR LSZ251-266-267.
LAKE MICHIGAN...
DENSE FOG ADVISORY UNTIL MIDNIGHT EDT TONIGHT FOR LMZ221-248-250.
&&
$$
SHORT TERM...VOSS
LONG TERM...TITUS
AVIATION...VOSS
MARINE...VOSS
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
523 AM EDT MON JUN 22 2015
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 522 AM EDT MON JUN 22 2015
WV IMAGERY AND RAP ANALYSIS INDICATES A ZONAL PATTERN ACROSS THE NRN
CONUS WITH A WELL-DEFINED SHORTWAVE TROUGH UPSTREAM OVER SRN
SASKATCHEWAN AND NE MT. THIS SHORTWAVE HAS AIDED IN THE DEVELOPMENT
OF AN MCS WHICH HAS ENVELOPED MUCH OF THE ERN HALF OF SD EARLY THIS
MORNING IN AN ENVIRONMENT OF HIGH MUCAPE...STRONG 850-700 MB
MOISTURE TRANSPORT AND STRONG DEEP LAYER SHEAR. OVER UPPER MI THE
WEATHER IS MUCH QUIETER AND GENERALLY PCPN FREE UNDER SFC HIGH PRES
RIDGE. AREAS OF FOG HAVE DEVELOPED ESPECIALLY OVER THE ERN HALF OF
THE CWA AND OVER LAKE MI AS HIGHER DEWPOINTS IN THE MID TO UPPER 50S
CONTINUE TO ADVECT NORTHWARD AHEAD OF THE SYSTEM APPROACHING FM THE
NRN PLAINS.
TODAY...LATEST 03Z SREF ENSEMBLE DATA ALONG WITH MAJORITY OF 00Z AND
06Z OPERATIONAL MODEL RUNS INDICATE THE MCS OVER SD WILL CONTINUE TO
TRACK ESE INTO SRN MN AND THE SRN HALF OF WI THIS MORNING INTO EARLY
AFTERNOON FOLLOWING THE GRADIENT OF HIGHEST MLCAPE/MUCAPES IN EXCESS
OF 2000 J/KG. CONTINUED TO FOLLOW PREV FCST SHIFT WITH SLOWER PCPN
ARRIVAL BACKING OFF PCPN TIMING/POPS INTO WRN UPPER MI UNTIL LATE
MORNING AND INTO CENTRAL UPPER MI EARLY/MID AFTERNOON WHEN DEEP
LAYER Q-VECT CONV AND MID-LVL MOISTURE ARRIVES AHEAD OF THE NRN
PLAINS SHORTWAVE ALONG WITH STRONG ISENTROPIC ASCENT AT THE NOSE OF
THE IMPINGING 30-40 KT LOW-LVL JET. INCREASING CONVECTIVE CLOUD
DEBRIS SPREADING IN AHEAD OF MCS TO THE SW WILL TEND TO LIMIT
EXTREME INSTABILITY FROM REACHING FAR NORTH INTO UPPER MI.
HOWEVER...IF ENOUGH CLEARING/HEATING DEVELOPS IN THE AFTERNOON
BEHIND THE INITIAL BATCH OF CONVECTIVE DEBRIS OR LIGHT RAIN TO BOOST
TEMPS TO THE MID 70S AND CAPES TO AROUND 1K J/KG...SEVERE TSRA WILL
BE POSSIBLE AS THE SHORTWAVE AND SFC TROUGH APPROACH. LARGE 0-6KM/0-
1KM SHEAR VALUE OF 55-70KT/30-40KT AND LARGE HELICITY VALUES WILL
SUPPORT THE POTENTIAL FOR SUPERCELL DEVELOPMENT THAT COULD
EVOLVE/ORGANIZE INTO SEVERE STORM CLUSTERS OR AN MCS. DAMAGING
WINDS...LARGE HAIL AND EVEN A TORNADO WOULD BE POSSIBLE MAINLY OVER
THE FAR SCNTRL FCST AREA...CLOSER TO THE HIGHER INSTABILITY GRADIENT
TO THE SOUTH.
TONIGHT...MAY SEE SOME LIGHT RAIN SHOWERS/DRIZZLE OVER FAR ERN UPPER
MI DOWNWIND OF LAKE SUPERIOR AS A POTENT SYSTEM MOVES EAST OUT OF
THE AREA. OTHERWISE...SFC HIGH PRESSURE MOVING INTO THE REGION WILL
LEAD TO CLEARING SKIES LATE TONIGHT WITH GUSTY NW WINDS ON THE
BACKSIDE OF THE SYSTEM. THE STRONG WINDS POSSIBLY REACHING 40 MPH
NEAR THE LAKE SUPERIOR SHORELINE FROM PICTURED ROCKS EASTWARD COULD
LEAD TO MINOR BEACH EROSION.
.LONG TERM...(TUESDAY THROUGH SUNDAY)
ISSUED AT 338 AM EDT MON JUN 22 2015
MAY SEE SOME LIGHT RAIN SHOWERS/DRIZZLE OVER FAR ERN UPPER MI
DOWNWIND OF LAKE SUPERIOR AS A POTENT SYSTEM MOVES OUT OF THE AREA.
OTHERWISE...SFC HIGH PRESSURE MOVING INTO THE REGION WILL LEAD TO
CLEARING SKIES. BREEZY CONDITIONS IN THE MORNING WILL DIMINISH
TROUGH THE DAY AS THE PRESSURE GRADIENT WEAKENS. EXPECT HIGH TEMPS
IN THE 60S AND 70S.
COULD SEE SOME LIGHT SHOWERS OVER THE NRN CWA LATE TUE EVENING INTO
TUE NIGHT AS A WEAK SHORTWAVE MOVES DOWN THE NW FLOW. MODELS SHOW
THOSE DIMINISHING AS INSTABILITY WEAKENS LATE IN THE DAY AND ALREADY
LIMITED MOISTURE STAYS OVER THE NRN CWA. WILL CONTINUE SLIGHT CHANCE
TO LOW CHANCE POPS.
NEXT SHORTWAVE MOVES IN AROUND PEAK HEATING WED
AFTERNOON/EVENING...WHICH SHOULD BE ABLE TO GENERATE SHOWERS MAINLY
OVER LAND AREAS. WITH LIMITED INSTABILITY JUST WENT WITH SLIGHT
CHANCES OF THUNDER. TEMPS SHOULD BE SIMILAR TO TUE WITH HIGHS IN THE
60S AND 70S.
NOT REAL SURE ON THE FORECAST FOR WED NIGHT INTO THU NIGHT AS MODEL
VARY ON THE TIMING OF A STRONGER SHORTWAVE. THE ECMWF AND NAM ARE
FASTER THAN THE GFS...RESULTING IN SHOWERS AND POSSIBLY SOME THUNDER
WED NIGHT INTO THU BUT MOSTLY DRY THU NIGHT WHILE THE GFS IS ABOUT
12 HOURS SLOWER.
LOTS OF UNCERTAINTY LOOKING AT THE WEEKEND...ESPECIALLY LATER IN THE
WEEKEND...SO WILL JUST RUN WITH A CONSENSUS BLEND.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT)
ISSUED AT 133 AM EDT MON JUN 22 2015
WITH THE EXCEPTION OF FOG/STRATUS DEVELOPING AT KSAW...FAIRLY QUIET
WEATHER IS EXPECTED FOR THE FIRST PART OF THE FORECAST...FOLLOWED BY
ACTIVE WEATHER WITH HEAVIER RAIN AND MVFR CONDITIONS ARRIVING BY MON
AFTERNOON. ENOUGH LOW LEVEL MOISTURE IS EXPECTED AT SAW FOR SOME FOG
AND LOWER CIGS TO REDEVELOP OVERNIGHT AIDED BY WEAK SRLY FLOW.
LIFR/VLIFR CONDITIONS WILL DEVELOP WITH SOUTH UPSLOPE FLOW OFF OF
LAKE MICHIGAN AT SAW AND THEY SHOULD AGAIN LIFT TO VFR BY MID TO LATE
MORNING. THERE PROBABLY WILL BE THUNDER AT TIMES MON...BUT CONFIDENCE
LOW ENOUGH TO KEEP OUT OF FORECAST FOR NOW. WILL GET GUSTY IN THE
AFTERNOON OUT AHEAD OF A COLD FRONT AND IN THE EVENING BEHIND A COLD
FRONT AT ALL SITES.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 515 AM EDT MON JUN 22 2015
A LOW PRES SYSTEM FROM THE NORTHERN PLAINS WILL OVE OVER THE UPPER
GREAT LAKES TODAY INTO THIS EVENING. A TIGHT PRES GRADIENT AND COLD
ADVECTION ON THE BACK SIDE OF THIS LOW WILL SUPPORT A PERIOD OF WNW
35 KNOT GALES LATE TONIGHT INTO TUE MORNING...STRONGEST OVER THE
EAST HALF OF LAKE SUPERIOR. HIGH PRES BUILDING BACK OVER THE AREA
WILL THEN KEEP WINDS LIGHT AGAIN FROM LATE TUE INTO THU.
LINGERING LOW-LVL MOISTURE AND HIGH DEWPOINTS WILL SUPPORT FOG
ACROSS THE LAKE...THAT COULD BE LOCALLY DENSE INTO THIS EVENING.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
GALE WARNING FROM 1 AM TO 10 AM EDT TUESDAY FOR LSZ251-266-267.
LAKE MICHIGAN...
DENSE FOG ADVISORY UNTIL MIDNIGHT EDT TONIGHT FOR LMZ221-248-250.
&&
$$
SHORT TERM...VOSS
LONG TERM...TITUS
AVIATION...07
MARINE...VOSS
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
517 AM EDT MON JUN 22 2015
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 515 AM EDT MON JUN 22 2015
WV IMAGERY AND RAP ANALYSIS INDICATES A ZONAL PATTERN ACROSS THE NRN
CONUS WITH A WELL-DEFINED SHORTWAVE TROUGH UPSTREAM OVER SRN
SASKATCHEWAN AND NE MT. THIS SHORTWAVE HAS AIDED IN THE DEVELOPMENT
OF AN MCS WHICH HAS ENVELOPED MUCH OF THE ERN HALF OF SD EARLY THIS
MORNING IN AN ENVIRONMENT OF HIGH MUCAPE...STRONG 850-700 MB
MOISTURE TRANSPORT AND STRONG DEEP LAYER SHEAR. OVER UPPER MI THE
WEATHER IS MUCH QUIETER AND GENERALLY PCPN FREE UNDER SFC HIGH PRES
RIDGE. AREAS OF FOG HAVE DEVELOPED ESPECIALLY OVER THE ERN HALF OF
THE CWA AND OVER LAKE MI AS HIGHER DEWPOINTS IN THE MID TO UPPER 50S
CONTINUE TO ADVECT NORTHWARD AHEAD OF THE SYSTEM APPROACHING FM THE
NRN PLAINS.
TODAY...LATEST 03Z SREF ENSEMBLE DATA ALONG WITH MAJORITY OF 00Z AND
06Z OPERATIONAL MODEL RUNS INDICATE THE MCS OVER SD WILL CONTINUE TO
TRACK ESE INTO SRN MN AND THE SRN HALF OF WI THIS MORNING INTO EARLY
AFTERNOON FOLLOWING THE GRADIENT OF HIGHEST MLCAPE/MUCAPES IN EXCESS
OF 2000 J/KG. CONTINUED TO FOLLOW PREV FCST SHIFT WITH SLOWER PCPN
ARRIVAL BACKING OFF PCPN TIMING/POPS INTO WRN UPPER MI UNTIL LATE
MORNING AND INTO CENTRAL UPPER MI EARLY/MID AFTERNOON WHEN DEEP
LAYER Q-VECT CONV AND MID-LVL MOISTURE ARRIVES AHEAD OF THE NRN
PLAINS SHORTWAVE ALONG WITH STRONG ISENTROPIC ASCENT AT THE NOSE OF
THE IMPINGING 30-40 KT LOW-LVL JET. INCREASING CONVECTIVE CLOUD
DEBRIS SPREADING IN AHEAD OF MCS TO THE SW WILL TEND TO LIMIT
EXTREME INSTABILITY FROM REACHING FAR NORTH INTO UPPER MI.
HOWEVER...IF ENOUGH CLEARING/HEATING DEVELOPS IN THE AFTERNOON
BEHIND THE INITIAL BATCH OF CONVECTIVE DEBRIS OR LIGHT RAIN TO BOOST
TEMPS TO THE MID 70S AND CAPES TO AROUND 1K J/KG...SEVERE TSRA WILL
BE POSSIBLE AS THE SHORTWAVE AND SFC TROUGH APPROACH. LARGE 0-6KM/0-
1KM SHEAR VALUE OF 55-70KT/30-40KT AND LARGE HELICITY VALUES WILL
SUPPORT THE POTENTIAL FOR SUPERCELL DEVELOPMENT THAT COULD
EVOLVE/ORGANIZE INTO SEVERE STORM CLUSTERS OR AN MCS. DAMAGING
WINDS...LARGE HAIL AND EVEN A TORNADO WOULD BE POSSIBLE MAINLY OVER
THE FAR SCNTRL FCST AREA...CLOSER TO THE HIGHER INSTABILITY GRADIENT
TO THE SOUTH.
TONIGHT...MAY SEE SOME LIGHT RAIN SHOWERS/DRIZZLE OVER FAR ERN UPPER
MI DOWNWIND OF LAKE SUPERIOR AS A POTENT SYSTEM MOVES EAST OUT OF
THE AREA. OTHERWISE...SFC HIGH PRESSURE MOVING INTO THE REGION WILL
LEAD TO CLEARING SKIES LATE TONIGHT WITH GUSTY NW WINDS ON THE
BACKSIDE OF THE SYSTEM...POSSIBLY REACHING 40 MPH NEAR THE LAKE
SUPERIOR SHORELINE FROM PICTURED ROCKS EASTWARD.
.LONG TERM...(TUESDAY THROUGH SUNDAY)
ISSUED AT 338 AM EDT MON JUN 22 2015
MAY SEE SOME LIGHT RAIN SHOWERS/DRIZZLE OVER FAR ERN UPPER MI
DOWNWIND OF LAKE SUPERIOR AS A POTENT SYSTEM MOVES OUT OF THE AREA.
OTHERWISE...SFC HIGH PRESSURE MOVING INTO THE REGION WILL LEAD TO
CLEARING SKIES. BREEZY CONDITIONS IN THE MORNING WILL DIMINISH
TROUGH THE DAY AS THE PRESSURE GRADIENT WEAKENS. EXPECT HIGH TEMPS
IN THE 60S AND 70S.
COULD SEE SOME LIGHT SHOWERS OVER THE NRN CWA LATE TUE EVENING INTO
TUE NIGHT AS A WEAK SHORTWAVE MOVES DOWN THE NW FLOW. MODELS SHOW
THOSE DIMINISHING AS INSTABILITY WEAKENS LATE IN THE DAY AND ALREADY
LIMITED MOISTURE STAYS OVER THE NRN CWA. WILL CONTINUE SLIGHT CHANCE
TO LOW CHANCE POPS.
NEXT SHORTWAVE MOVES IN AROUND PEAK HEATING WED
AFTERNOON/EVENING...WHICH SHOULD BE ABLE TO GENERATE SHOWERS MAINLY
OVER LAND AREAS. WITH LIMITED INSTABILITY JUST WENT WITH SLIGHT
CHANCES OF THUNDER. TEMPS SHOULD BE SIMILAR TO TUE WITH HIGHS IN THE
60S AND 70S.
NOT REAL SURE ON THE FORECAST FOR WED NIGHT INTO THU NIGHT AS MODEL
VARY ON THE TIMING OF A STRONGER SHORTWAVE. THE ECMWF AND NAM ARE
FASTER THAN THE GFS...RESULTING IN SHOWERS AND POSSIBLY SOME THUNDER
WED NIGHT INTO THU BUT MOSTLY DRY THU NIGHT WHILE THE GFS IS ABOUT
12 HOURS SLOWER.
LOTS OF UNCERTAINTY LOOKING AT THE WEEKEND...ESPECIALLY LATER IN THE
WEEKEND...SO WILL JUST RUN WITH A CONSENSUS BLEND.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT)
ISSUED AT 133 AM EDT MON JUN 22 2015
WITH THE EXCEPTION OF FOG/STRATUS DEVELOPING AT KSAW...FAIRLY QUIET
WEATHER IS EXPECTED FOR THE FIRST PART OF THE FORECAST...FOLLOWED BY
ACTIVE WEATHER WITH HEAVIER RAIN AND MVFR CONDITIONS ARRIVING BY MON
AFTERNOON. ENOUGH LOW LEVEL MOISTURE IS EXPECTED AT SAW FOR SOME FOG
AND LOWER CIGS TO REDEVELOP OVERNIGHT AIDED BY WEAK SRLY FLOW.
LIFR/VLIFR CONDITIONS WILL DEVELOP WITH SOUTH UPSLOPE FLOW OFF OF
LAKE MICHIGAN AT SAW AND THEY SHOULD AGAIN LIFT TO VFR BY MID TO LATE
MORNING. THERE PROBABLY WILL BE THUNDER AT TIMES MON...BUT CONFIDENCE
LOW ENOUGH TO KEEP OUT OF FORECAST FOR NOW. WILL GET GUSTY IN THE
AFTERNOON OUT AHEAD OF A COLD FRONT AND IN THE EVENING BEHIND A COLD
FRONT AT ALL SITES.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 515 AM EDT MON JUN 22 2015
A LOW PRES SYSTEM FROM THE NORTHERN PLAINS WILL OVE OVER THE UPPER
GREAT LAKES TODAY INTO THIS EVENING. A TIGHT PRES GRADIENT AND COLD
ADVECTION ON THE BACK SIDE OF THIS LOW WILL SUPPORT A PERIOD OF WNW
35 KNOT GALES LATE TONIGHT INTO TUE MORNING...STRONGEST OVER THE
EAST HALF OF LAKE SUPERIOR. HIGH PRES BUILDING BACK OVER THE AREA
WILL THEN KEEP WINDS LIGHT AGAIN FROM LATE TUE INTO THU.
LINGERING LOW-LVL MOISTURE AND HIGH DEWPOINTS WILL SUPPORT FOG
ACROSS THE LAKE...THAT COULD BE LOCALLY DENSE INTO THIS EVENING.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
GALE WARNING FROM 1 AM TO 10 AM EDT TUESDAY FOR LSZ251-266-267.
LAKE MICHIGAN...
DENSE FOG ADVISORY UNTIL MIDNIGHT EDT TONIGHT FOR LMZ221-248-250.
&&
$$
SHORT TERM...VOSS
LONG TERM...TITUS
AVIATION...07
MARINE...VOSS
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
339 AM EDT MON JUN 22 2015
.SHORT TERM...(THIS EVENING THROUGH MONDAY)
ISSUED AT 437 PM EDT SUN JUN 21 2015
WV IMAGERY AND RAP ANALYSIS INDICATED A ZONAL PATTERN ACROSS THE NRN
CONUS. THE NEXT SIGNIFICANT UPSTREAM SHORTWAVE TROUGH WAS LOCATED
FROM SRN ALBERTA INTO NW MONTANA. AT THE SFC...A WEAK RIDGE EXTENDED
FROM WRN LAKE SUPERIOR INTO WI. THE MAIN FRONTAL BOUNDARY WAS WELL
TO THE SOUTH...EXTENDING FROM NRN KS TO CNTRL INDIANA. SATELLITE LOOP
SHOWED CLEARING OVER THE WEST AND SOUTH WITH LINGERING CLOUDS OVER
THE NORTH AND EAST.
TONIGHT...MID-LVL RIDGING MOVING ACROSS THE AREA WILL KEEP THE FCST
AREA DRY. HIGHER DEW POINTS IN THE UPPER 50S ADVECTING IN WITH A
DEVELOPING SOUTHERLY FLOW AHEAD OF PLAINS SYSTEM WILL ALSO
CONTRIBUTE TO MORE FOG/STRATUS FORMATION ACROSS MUCH OF THE
CWA...ESPECIALLY LATE TONIGHT OVER THE EAST HALF OF UPPER
MI...DOWNWIND OF LAKE MICHIGAN.
MON...THE MORE PLAUSIBLE HIGHER RES MODEL SCENARIO...SHOWS AN
ONGOING MCS INTO SRN MN WILL SPREAD TO THE ESE TO SRN WI OR NRN IL
ALONG OR NEAR THE MUCAPE GRADIENT. SO...HAVE BACKED OFF ON THE PCPN
TIMING/POPS INTO WRN UPPER MI MON MORNING INTO EARLY AFTERNOON AS
THE GFS AND ESPECIALLY THE NAM SEEM TOO AGGRESSIVE WITH THE PCPN.
SEVERAL OF THE HIGH RES MODELS KEEP UPPER MI DRY THROUGH 18Z.
SHOWERS AND SOME EMBEDDED TSRA MAY SPREAD INTO THE WEST HALF IN THE
MORNING SUPPORTED INCREASING MOISTURE ADVECTION AND 305K-310K
ISENTROPIC LIFT AHEAD OF THE TROUGH MOVING TOWARD THE UPPER MS
VALLEY. HOWEVER...CONFIDENCE IN PCPN COVERAGE/TIMING IS LOW WITH
UNCERTAINTY ON THE IMPACTS OF THE MCS TO THE SOUTH. IF ENOUGH
CLEARING/HEATING DEVELOPS IN THE AFTERNOON BEHIND THE INITIAL BATCH
OF CONVECTIVE DEBRIS OR LIGHT RAIN TO BOOST TEMPS TO THE MID 70S AND
CAPES TO AROUND 1K J/KG...SEVERE TSRA WILL BE POSSIBLE AS THE
SHORTWAVE AND SFC TROUGH APPROACH. LARGE 0-6KM/0-1KM SHEAR VALUE OF
50-60KT/30-40KT AND LARGE HELICITY VALUES WILL SUPPORT THE POTENTIAL
FOR SUPERCELL DEVELOPMENT THAT MAY EVOLVE/ORGANIZE INTO SEVERE STORM
CLUSTERS OR AN MCS. DAMAGING WINDS...LARGE HAIL AND EVEN TORNADOS
WOULD BE POSSIBLE. HOWEVER...THIS IS CONDITIONAL AS CONFIDENCE IN THE
AMOUNT OF INSTABILITY THAT WILL DEVELOP IS LOW.
.LONG TERM...(TUESDAY THROUGH SUNDAY)
ISSUED AT 338 AM EDT MON JUN 22 2015
MAY SEE SOME LIGHT RAIN SHOWERS/DRIZZLE OVER FAR ERN UPPER MI
DOWNWIND OF LAKE SUPERIOR AS A POTENT SYSTEM MOVES OUT OF THE AREA.
OTHERWISE...SFC HIGH PRESSURE MOVING INTO THE REGION WILL LEAD TO
CLEARING SKIES. BREEZY CONDITIONS IN THE MORNING WILL DIMINISH
TROUGH THE DAY AS THE PRESSURE GRADIENT WEAKENS. EXPECT HIGH TEMPS
IN THE 60S AND 70S.
COULD SEE SOME LIGHT SHOWERS OVER THE NRN CWA LATE TUE EVENING INTO
TUE NIGHT AS A WEAK SHORTWAVE MOVES DOWN THE NW FLOW. MODELS SHOW
THOSE DIMINISHING AS INSTABILITY WEAKENS LATE IN THE DAY AND ALREADY
LIMITED MOISTURE STAYS OVER THE NRN CWA. WILL CONTINUE SLIGHT CHANCE
TO LOW CHANCE POPS.
NEXT SHORTWAVE MOVES IN AROUND PEAK HEATING WED
AFTERNOON/EVENING...WHICH SHOULD BE ABLE TO GENERATE SHOWERS MAINLY
OVER LAND AREAS. WITH LIMITED INSTABILITY JUST WENT WITH SLIGHT
CHANCES OF THUNDER. TEMPS SHOULD BE SIMILAR TO TUE WITH HIGHS IN THE
60S AND 70S.
NOT REAL SURE ON THE FORECAST FOR WED NIGHT INTO THU NIGHT AS MODEL
VARY ON THE TIMING OF A STRONGER SHORTWAVE. THE ECMWF AND NAM ARE
FASTER THAN THE GFS...RESULTING IN SHOWERS AND POSSIBLY SOME THUNDER
WED NIGHT INTO THU BUT MOSTLY DRY THU NIGHT WHILE THE GFS IS ABOUT
12 HOURS SLOWER.
LOTS OF UNCERTAINTY LOOKING AT THE WEEKEND...ESPECIALLY LATER IN THE
WEEKEND...SO WILL JUST RUN WITH A CONSENSUS BLEND.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT)
ISSUED AT 133 AM EDT MON JUN 22 2015
WITH THE EXCEPTION OF FOG/STRATUS DEVELOPING AT KSAW...FAIRLY QUIET
WEATHER IS EXPECTED FOR THE FIRST PART OF THE FORECAST...FOLLOWED BY
ACTIVE WEATHER WITH HEAVIER RAIN AND MVFR CONDITIONS ARRIVING BY MON
AFTERNOON. ENOUGH LOW LEVEL MOISTURE IS EXPECTED AT SAW FOR SOME FOG
AND LOWER CIGS TO REDEVELOP OVERNIGHT AIDED BY WEAK SRLY FLOW.
LIFR/VLIFR CONDITIONS WILL DEVELOP WITH SOUTH UPSLOPE FLOW OFF OF
LAKE MICHIGAN AT SAW AND THEY SHOULD AGAIN LIFT TO VFR BY MID TO LATE
MORNING. THERE PROBABLY WILL BE THUNDER AT TIMES MON...BUT CONFIDENCE
LOW ENOUGH TO KEEP OUT OF FORECAST FOR NOW. WILL GET GUSTY IN THE
AFTERNOON OUT AHEAD OF A COLD FRONT AND IN THE EVENING BEHIND A COLD
FRONT AT ALL SITES.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 437 PM EDT SUN JUN 21 2015
HIGH PRES OVER THE AREA TONIGHT WILL KEEP WINDS UNDER 20 KTS. A LOW
PRES SYSTEM WILL THEN MOVE OVER THE UPPER GREAT LAKES MONDAY INTO
MON EVENING. A TIGHT PRES GRADIENT AND COLD ADVECTION ON THE BACK
SIDE OF THIS LOW WILL SUPPORT A PERIOD OF WNW 35 KNOT GALES LATE
MONDAY NIGHT INTO TUE MORNING...STRONGEST OVER THE EAST HALF OF LAKE
SUPERIOR. HIGH PRES BUILDING BACK OVER THE AREA WILL THEN KEEP WINDS
LIGHT AGAIN FROM LATE TUE INTO THU.
LINGERING LOW-LVL MOISTURE WILL SUPPORT FOG ACROSS THE LAKE...THAT
COULD BE LOCALLY DENSE FROM TONIGHT INTO MONDAY.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
GALE WARNING FROM 1 AM TO 10 AM EDT TUESDAY FOR LSZ251-266-267.
LAKE MICHIGAN...
DENSE FOG ADVISORY UNTIL MIDNIGHT EDT TONIGHT FOR LMZ221-248-250.
&&
$$
SHORT TERM...JLB
LONG TERM...TITUS
AVIATION...07
MARINE...JLB
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
138 AM EDT MON JUN 22 2015
.SHORT TERM...(THIS EVENING THROUGH MONDAY)
ISSUED AT 437 PM EDT SUN JUN 21 2015
WV IMAGERY AND RAP ANALYSIS INDICATED A ZONAL PATTERN ACROSS THE NRN
CONUS. THE NEXT SIGNIFICANT UPSTREAM SHORTWAVE TROUGH WAS LOCATED
FROM SRN ALBERTA INTO NW MONTANA. AT THE SFC...A WEAK RIDGE EXTENDED
FROM WRN LAKE SUPERIOR INTO WI. THE MAIN FRONTAL BOUNDARY WAS WELL
TO THE SOUTH...EXTENDING FROM NRN KS TO CNTRL INDIANA. SATELLITE LOOP
SHOWED CLEARING OVER THE WEST AND SOUTH WITH LINGERING CLOUDS OVER
THE NORTH AND EAST.
TONIGHT...MID-LVL RIDGING MOVING ACROSS THE AREA WILL KEEP THE FCST
AREA DRY. HIGHER DEW POINTS IN THE UPPER 50S ADVECTING IN WITH A
DEVELOPING SOUTHERLY FLOW AHEAD OF PLAINS SYSTEM WILL ALSO
CONTRIBUTE TO MORE FOG/STRATUS FORMATION ACROSS MUCH OF THE
CWA...ESPECIALLY LATE TONIGHT OVER THE EAST HALF OF UPPER
MI...DOWNWIND OF LAKE MICHIGAN.
MON...THE MORE PLAUSIBLE HIGHER RES MODEL SCENARIO...SHOWS AN
ONGOING MCS INTO SRN MN WILL SPREAD TO THE ESE TO SRN WI OR NRN IL
ALONG OR NEAR THE MUCAPE GRADIENT. SO...HAVE BACKED OFF ON THE PCPN
TIMING/POPS INTO WRN UPPER MI MON MORNING INTO EARLY AFTERNOON AS
THE GFS AND ESPECIALLY THE NAM SEEM TOO AGGRESSIVE WITH THE PCPN.
SEVERAL OF THE HIGH RES MODELS KEEP UPPER MI DRY THROUGH 18Z.
SHOWERS AND SOME EMBEDDED TSRA MAY SPREAD INTO THE WEST HALF IN THE
MORNING SUPPORTED INCREASING MOISTURE ADVECTION AND 305K-310K
ISENTROPIC LIFT AHEAD OF THE TROUGH MOVING TOWARD THE UPPER MS
VALLEY. HOWEVER...CONFIDENCE IN PCPN COVERAGE/TIMING IS LOW WITH
UNCERTAINTY ON THE IMPACTS OF THE MCS TO THE SOUTH. IF ENOUGH
CLEARING/HEATING DEVELOPS IN THE AFTERNOON BEHIND THE INITIAL BATCH
OF CONVECTIVE DEBRIS OR LIGHT RAIN TO BOOST TEMPS TO THE MID 70S AND
CAPES TO AROUND 1K J/KG...SEVERE TSRA WILL BE POSSIBLE AS THE
SHORTWAVE AND SFC TROUGH APPROACH. LARGE 0-6KM/0-1KM SHEAR VALUE OF
50-60KT/30-40KT AND LARGE HELICITY VALUES WILL SUPPORT THE POTENTIAL
FOR SUPERCELL DEVELOPMENT THAT MAY EVOLVE/ORGANIZE INTO SEVERE STORM
CLUSTERS OR AN MCS. DAMAGING WINDS...LARGE HAIL AND EVEN TORNADOS
WOULD BE POSSIBLE. HOWEVER...THIS IS CONDITIONAL AS CONFIDENCE IN THE
AMOUNT OF INSTABILITY THAT WILL DEVELOP IS LOW.
.LONG TERM...(MONDAY NIGHT THROUGH SUNDAY)
ISSUED AT 259 PM EDT SUN JUN 21 2015
A POTENT SHORTWAVE WILL BE MOVING ACROSS THE GREAT LAKES REGION AT
THE START OF THE LONG TERM PERIOD. A SURFACE LOW OF AROUND 1000MB
WILL BE LOCATED OVER CENTRAL UPPER MICHIGAN AT THE START OF THE
PERIOD AND IT WILL QUICKLY MOVE NORTH OF LAKE HURON BY 06Z AND
CONTINUE TO THE NORTHEAST INTO QUEBEC BY 12Z TUESDAY. CONVECTION
EARLIER IN THE DAY WILL DETERMINE THE EVOLUTION OF THE POPS FOR
THE MONDAY NIGHT PERIOD...BUT WILL SHOW THE HIGHEST POPS OVER THE
EASTERN CWA AHEAD OF THE SURFACE LOW AND WITH THE COLD FRONT MOVING
EAST THROUGH THE AREA. BEHIND THESE FEATURES...A TRAILING SURFACE
TROUGH TO THE NORTHWEST MAY LEAD TO A SECONDARY AREA OF SHOWERS
UNDER THE WRAP AROUND NORTHWESTERLY FLOW DURING THE EVENING AND
EARLY OVERNIGHT HOURS IN THE WESTERN CWA AND THEN OVER THE NORTH
CENTRAL AND EAST LATE IN THE NIGHT INTO THE FIRST HALF OF TUESDAY
MORNING. WILL JUST SHOW SLIGHT CHANCE WORDING FOR THOSE SHOWERS.
GUSTY NORTHWESTERLY WINDS WILL DEVELOP ON THE BACK SIDE OF THE
LOW...WITH GUSTS UP TO 30 KNOTS OVER LAKE SUPERIOR AND THE SHORELINE
AREAS. WINDS JUST ABOVE THE SURFACE ARE IN THE 35-40KT RANGE ON ALL
OF THE MODELS...WHILE THE OVER LAKE INSTABILITY IS STILL VERY LOW AS
TEMPERATURES JUST ABOVE THE SURFACE ARE STILL AROUND 13-14C. BUT
WITH DECENT PRESSURE FALLS BEHIND THE LOW ON EASTERN LAKE
SUPERIOR...FEEL COMFORTABLE ENOUGH PUTTING IN SOME GALE FORCE GUSTS
IN THAT AREA FOR LATE MONDAY NIGHT INTO TUESDAY MORNING.
A HIGH PRESSURE RIDGE WILL QUICKLY MOVE INTO UPPER MICHIGAN ON
TUESDAY AND DIMINISH THE WINDS ACROSS THE AREA. OTHERWISE...EXPECT
ANY LINGERING LOW CLOUDS OVER THE AREA TUESDAY MORNING TO DIMINISH
BY THE AFTERNOON HOURS AND WITH AFTERNOON MIXING HIGHS SHOULD RISE
TO NEAR NORMAL VALUES. A WEAK SURFACE TROUGH WILL DROP SOUTHEAST
INTO THE AREA ON TUESDAY NIGHT. EXPECT SHOWERS TO BE OCCURRING OVER
NORTHWESTERN ONTARIO WITH THE TROUGH...BUT THE LOSS OF DIURNAL
HEATING AND THE MAIN SHORTWAVE FORCING AND MOISTURE BRUSHING
NORTHEAST LAKE SUPERIOR WILL KEEP THE SHOWERS MAINLY OVER THAT
PORTION OF THE LAKE. BEHIND THAT WAVE...THE AREA WILL BE BETWEEN
SYSTEMS ON WEDNESDAY MORNING...AS THE NEXT SHORTWAVE APPROACHES FROM
THE WEST. THIS WILL LEAD TO SHOWERS MOVING INTO OR DEVELOPING OVER
WESTERN UPPER MICHIGAN LATER WEDNESDAY AFTERNOON AND CONTINUING INTO
WEDNESDAY NIGHT. THERE ARE SOME HINTS OF WEAK INSTABILITY WITH THIS
NEXT WAVE (EVEN WITH THE SHORTWAVE MOVING THROUGH AT A
CLIMATOLOGICALLY POOR TIME)...SO WILL MENTION JUST A SLIGHT CHANCE
OF THUNDER. THIS WAVE WILL CONTINUE TO PRODUCE THE POTENTIAL FOR
SHOWERS/THUNDERSTORMS OVER THE AREA INTO THURSDAY. MODELS DIFFER ON
HOW QUICKLY THE LAST OF THE EMBEDDED SHORTWAVES DEPARTS THE AREA ON
THURSDAY NIGHT...SO WILL SLOWLY DIMINISH POPS DURING THAT PERIOD.
HIGH PRESSURE MOVES INTO THE AREA FOR FRIDAY...BUT COULD STILL SEE
SOME DIURNAL SHOWERS OVER THE INTERIOR WEST/CENTRAL AND WILL HAVE
SLIGHT CHANCE POPS DURING THE LATE MORNING AND AFTERNOON.
MODELS CONTINUE TO SHOW THE FLOW TRANSITIONING TO NORTHWESTERLY
ALOFT AS AN UPPER TROUGH DEVELOP OVER THE GREAT LAKES REGION. THIS
MAY PUSH A FEW WEAK WAVES ACROSS THE AREA THIS WEEKEND...BUT RAIN
POTENTIAL LOOKS TO BE LIMITED AT THIS TIME.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT)
ISSUED AT 133 AM EDT MON JUN 22 2015
WITH THE EXCEPTION OF FOG/STRATUS DEVELOPING AT KSAW...FAIRLY QUIET
WEATHER IS EXPECTED FOR THE FIRST PART OF THE FORECAST...FOLLOWED BY
ACTIVE WEATHER WITH HEAVIER RAIN AND MVFR CONDITIONS ARRIVING BY MON
AFTERNOON. ENOUGH LOW LEVEL MOISTURE IS EXPECTED AT SAW FOR SOME FOG
AND LOWER CIGS TO REDEVELOP OVERNIGHT AIDED BY WEAK SRLY FLOW.
LIFR/VLIFR CONDITIONS WILL DEVELOP WITH SOUTH UPSLOPE FLOW OFF OF
LAKE MICHIGAN AT SAW AND THEY SHOULD AGAIN LIFT TO VFR BY MID TO LATE
MORNING. THERE PROBABLY WILL BE THUNDER AT TIMES MON...BUT CONFIDENCE
LOW ENOUGH TO KEEP OUT OF FORECAST FOR NOW. WILL GET GUSTY IN THE
AFTERNOON OUT AHEAD OF A COLD FRONT AND IN THE EVENING BEHIND A COLD
FRONT AT ALL SITES. &&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 437 PM EDT SUN JUN 21 2015
HIGH PRES OVER THE AREA TONIGHT WILL KEEP WINDS UNDER 20 KTS. A LOW
PRES SYSTEM WILL THEN MOVE OVER THE UPPER GREAT LAKES MONDAY INTO
MON EVENING. A TIGHT PRES GRADIENT AND COLD ADVECTION ON THE BACK
SIDE OF THIS LOW WILL SUPPORT A PERIOD OF WNW 35 KNOT GALES LATE
MONDAY NIGHT INTO TUE MORNING...STRONGEST OVER THE EAST HALF OF LAKE
SUPERIOR. HIGH PRES BUILDING BACK OVER THE AREA WILL THEN KEEP WINDS
LIGHT AGAIN FROM LATE TUE INTO THU.
LINGERING LOW-LVL MOISTURE WILL SUPPORT FOG ACROSS THE LAKE...THAT
COULD BE LOCALLY DENSE FROM TONIGHT INTO MONDAY.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...JLB
LONG TERM...SRF
AVIATION...07
MARINE...JLB
AREA FORECAST DISCUSSION
NWS DULUTH MN
1240 AM CDT MON JUN 22 2015
.UPDATE...
ISSUED AT 1235 AM CDT MON JUN 22 2015
UPDATED AVIATION SECTION BELOW.
&&
.SHORT TERM...(THIS EVENING THROUGH MONDAY)
ISSUED AT 315 PM CDT SUN JUN 21 2015
CANT RULE OUT A STRAY SPRINKLE/LIGHT SHOWER THIS EVENING AS
LATEST SPC RUC ANALYSIS SHOWS 500-1000 J/KG OF CAPE SITTING OVER
THE FORECAST AREA. CURRENT RADAR IMAGERY IS PICKING UP ON A FEW
ISOLATED SHOWERS TRYING TO GAIN MOMENTUM OVER NW WISCONSIN.
HOWEVER...THESE SHOWERS WILL DISSIPATE NEAR SUNSET WITH THE LOSS
OF DAYTIME HEATING.
FOCUS TURNS TO THE ON GOING CONVECTION IN THE DAKOTAS...WHERE A
SVR THUNDERSTORM WATCH IS IN EFFECT. LATEST GUIDANCE CONTINUES TO
SUGGEST AN APPROACHING SHORT WAVE WITH DEEPENING H85/SFC LOW WILL
ALLOW THE CONVECTION TO DEVELOP INTO A MESOSCALE CONVECTIVE
COMPLEX...WHICH TRANSLATES ACROSS THE EASTERN DAKOTAS AND INTO
MINNESOTA OVERNIGHT. ALTHOUGH THE EXACT TRACK IS STILL SOMEWHAT
UNCERTAIN...LATEST HIGH RESOLUTION MODELS SHOW THE CONVECTION
REACHING THE WESTERN BORDER OF THE DLH CWA AROUND
MIDNIGHT...REACHING THE TWIN PORTS AROUND DAY BREAK MONDAY.
THE SHORT WAVES WITH SFC TROUGH/H85 LOW WILL CONTINUE ITS PUSH
EAST ACROSS THE FORECAST AREA THROUGH MONDAY AFTERNOON. THERE IS
A POTENTIAL FOR FEW STORMS TO BECOME STRONG TO SEVERE MONDAY. THE
MAIN THREAT FOR SEVERE WEATHER WILL BE ASSOCIATED WITH THE FRONTAL
PASSAGE OVER NORTHERN WISCONSIN. ALTHOUGH THERE IS SUFFICIENT
SHEAR AND MOISTURE TO SUPPORT ORGANIZED CONVECTION ACROSS THE
ENTIRE FORECAST AREA...THE CAPE VALUES ARE MAXIMIZED OVER
WISCONSIN DURING THE LATE MORNING/EARLY AFTERNOON.
.LONG TERM...(MONDAY NIGHT THROUGH SUNDAY)
ISSUED AT 315 PM CDT SUN JUN 21 2015
.LONG TERM...(MONDAY NIGHT THROUGH SUNDAY)
SEASONABLE TO MILD WEEK AHEAD WITH A CHANCE FOR SOME MID/LATE WEEK
SHOWERS AND STORMS.
ON THE SYNOPTIC SCALE THERE WILL BE FAST FLOW ALOFT WITH A 100KT JET
STREAK MOVING ACROSS THE NORTHERN TIER OF THE COUNTRY THROUGH THE
FIRST HALF OF THE WEEK. THIS IS MAINLY DUE TO A MID/UPPER LEVEL
RIDGE ACROSS THE SOUTHERN PLAINS INTO THE SOUTHEAST. EXPECTING QUIET
WEATHER ON TUESDAY...A CHANCE FOR SHOWERS AND STORMS LATE TUES INTO
THURSDAY...THEN A SLIGHT CHANCE FOR PRECIP THROUGH THE WEEKEND.
TEMPS WILL BE GENERALLY SEASONABLE TO MILD.
MONDAY NIGHT...SHOWERS/STORMS SHOULD BE EXITING THE REGION FOLLOWING
A LOW PRESSURE THAT MOVES THROUGH EARLIER IN THE DAY. PRECIP WILL
LIKELY END BY 06Z AS SUBSIDENCE DEVELOPS...WITH THE BEST CHANCE FOR
PRECIP ALONG THE INTERNATIONAL BORDER TO THE ARROWHEAD REGION.
TUESDAY...GENERALLY SUNNY AND DRY DUE TO AN AREA OF HIGH PRESSURE
OVER THE MID MISSISSIPPI VALLEY DRIFTING EAST. A FEW SHOWERS/STORMS
MAY FIRE ALONG THE INTERNATIONAL BORDER DUE TO A WEAK FRONT DRIFTING
SOUTH OUT OF CANADA. LOOKS LIKE ENOUGH INSTABILITY FOR A SMALL
HAIL/GUSTY WIND THREAT FROM THE STRONGEST STORMS...BUT SHEAR ALOFT
APPEARS TO BE INSUFFICIENT FOR WIDESPREAD SEVERE THUNDERSTORMS.
RELATIVE HUMIDITY VALUES COULD DROP TO 35-40 PERCENT IN THE
AFTERNOON...THOUGH THIS WILL DEPEND ON AFTERNOON CLOUD COVER. HIGHS
IN THE MID TO UPPER 70S WITH A LIGHT WEST WIND.
TUESDAY NIGHT INTO THURSDAY NIGHT...AS HIGH PRESSURE DRIFTS EASTWARD
THERE WILL BE A NUMBER OF WEAK DISTURBANCES IN THE MID-LEVEL FLOW
HEADED TOWARDS THE UPPER MIDWEST. THE PATTERN WILL BE FAIRLY
COMPLEX...BUT IN GENERAL EXPECT PRECIP CHANCES TO INCREASE FROM LATE
TUESDAY...THROUGH THURSDAY. MODEL DIFFERENCES MAKE IT TOUGH TO
DETERMINE WHICH DAY WOULD HAVE THE BEST CHANCE FOR PRECIP...BUT NO
DAY LOOKS LIKE A COMPLETE WASHOUT. TEMPS REMAINING NEAR NORMAL WITH
HIGHS IN THE MID TO UPPER 70S AND LOWS IN 50S.
FRI...SAT...SUN...SEASONABLE TO MILD PATTERN CONTINUES. FLOW ALOFT
BECOMES MORE NORTHWESTERLY AS A RIDGE DEVELOPS OVER THE WEST COAST
AND TROUGH EVENTUALLY DEEPENING OVER THE EASTERN THIRD OF THE
COUNTRY. THIS PATTERN WILL RESULT IN THE UPPER MIDWEST CONTINUING TO
BE IN THE PATH OF A NUMBER OF WEAK DISTURBANCES AND FRONTAL
PASSAGES. ECMWF/GFS/GEFS ARE ALL IN FAIRLY GOOD AGREEMENT WITH THIS
PATTERN...AND ALSO DEEPEN AN UPPER LOW SOMEWHERE NEAR HUDSON
BAY...WHICH MAY RESULT IN MORE ORGANIZED PATTERN SATURDAY/SUNDAY.
TEMPS AGAIN MORE OF THE SAME...HIGHS IN THE MID TO UPPER 70S AND
LOWS IN THE 50S.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT)
ISSUED AT 1235 AM CDT MON JUN 22 2015
VFR CONDITIONS AS OF ISSUANCE TIME TO BE OVERRUN BY A DECAYING
COMPLEX OF THUNDERSTORMS BEGINNING AROUND 08Z...BRINGING MVFR
CEILINGS AND VISIBILITIES TO KBRD...BUT REMAINING SITES SHOULD
REMAIN VFR AS THE COMPLEX TURNS SOUTHEAST IN THE NEXT FEW HOURS.
THE STORMS ARE PRODUCING IFR CEILINGS AND VISIBILITIES OVER
EASTERN ND AT THIS TIME...SO WILL HAVE TO WATCH STRENGTH OF STORMS
TO SEE IF ADJUSTMENTS ARE NEEDED. NEW STORM DEVELOPMENT IS
EXPECTED TO MOVE INTO THE TERMINALS AFTER 15Z...AND CONTINUE
THROUGH 21Z BEFORE THE SYSTEM SWEEPS EAST. FOR NOW HAVE GONE WITH
MAINLY VCTS AS UNCERTAINTY IN TIMING AND PLACEMENT OF THESE STORMS
IS FAIRLY HIGH.
&&
.PRELIMINARY POINT TEMPS/POPS...
DLH 53 76 55 76 / 10 0 10 30
INL 51 75 52 76 / 10 20 30 60
BRD 55 78 57 78 / 0 0 10 30
HYR 56 76 53 77 / 10 0 10 20
ASX 55 76 55 75 / 10 0 10 30
&&
.DLH WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
LS...NONE.
&&
$$
UPDATE...LE
SHORT TERM...GRANING
LONG TERM...JJM
AVIATION...LE
AREA FORECAST DISCUSSION
NWS SPRINGFIELD MO
621 PM CDT Tue Jun 23 2015
...00Z Aviation Update...
.SHORT TERM...(This Evening through Thursday)
Issued at 200 PM CDT TUE JUN 23 2015
A front has stalled out across the area. This frontal boundary
shows up very nicely on the visible satellite imagery and surface
obs this afternoon. The front was currently located from near
Nevada to near Eminence. This front will start to slowly back up
northward later this evening and tonight. There is a complex of
storms northwest of the Kansas City area which are moving east-
southeastward.
The latest Hi-Res models suggest this complex if it holds together
may clip our central Missouri counties late this afternoon and
early evening. The HRRR and the ARW continues to suggest a few
isolated showers and storms developing near the stalled out
frontal boundary across central Missouri into the eastern Missouri
Ozarks. There will be a limited risk for a strong storm or two
with small hail and gusty winds as the main threat. Any convection
should either dissipate or move off to the east of the area after sunset.
Wednesday and Thursday will be hot and humid with the upper level
ridge nosing in a bit over the area. High temperatures may be a
couple degrees warmer than today with most areas in the lower to
middle 90s. Heat index will be around 100. Southwest winds will be
gusty up to 30 mph for areas west of Highway 65.
.LONG TERM...(Thursday Night through Tuesday)
Issued at 200 PM CDT TUE JUN 23 2015
A stronger shortwave will move through the Midwest and Ohio River
Valley region on Friday. This feature will begin to carve out a
trough across the eastern U.S. while an upper level ridge builds
across the western U.S. A cold front will move down into the
region starting Thursday night. Showers and thunderstorms will
begin to impact portions of central Missouri late Thursday night
and area wide by Friday. Will not rule out a few strong storms
possible Friday with gusty winds and small hail the main threats.
The front will clear through the area by Friday night with rain
ending from north to south.
The weekend is shaping up to be extremely nice. Drier air will
move into the area with dewpoints in the 50s. The latest model
guidance came in a degree or two cooler with lows Saturday night
and Sunday night in the upper 50s to lower 60s. Highs will be in
the upper 70s to lower 80s and Mostly sunny skies. Looks like the
below average temperatures will continue into early next week.
Another weak front may try to move into the area by Monday night
with a few showers and storms possible.
&&
.AVIATION...(For the 00Z TAFS through 00Z Wednesday Evening)
Issued at 616 PM CDT TUE JUN 23 2015
Convection should remain north and east of the terminals this
evening, though mid and high level cloud cover can be expected
through the first part of the evening. A frontal boundary has just
moved through the SGF terminal, and it`s not clear whether it will
make to JLN before stalling; it is not expected to make it as far
as BBG. That boundary will then move back north later tonight. The
result will be initial north winds behind the front becoming
southeasterly, and then southwesterly by tomorrow.
&&
.SGF WATCHES/WARNINGS/ADVISORIES...
MO...NONE.
KS...NONE.
&&
$$
SHORT TERM...Griffin
LONG TERM...Griffin
AVIATION...Boxell
AREA FORECAST DISCUSSION
NWS KANSAS CITY/PLEASANT HILL MO
1153 PM CDT Sun Jun 21 2015
.DISCUSSION...
Issued at 518 PM CDT SUN JUN 21 2015
Tonight - Monday:
Elevated convection redeveloping across northwest MO where airmass
is being feed by increasing feed of accas forming across northeast
KS. While the HRRR has had some issues its also been adamant that
scattered convection would from over northwest MO late this
afternoon and evening. SPC Meso Analysis depicts region of deep
moisture convergence and advection of better instability into
northwest MO to support the continued development. Isolated severe
is possible as 40kt 0-6km shear supports activity. Convection will
likely begin to fall apart as we head towards sunset and instability
begins to wane. Boundary currently over west central MO will
eventually lift north and into IA overnight allowing southerly flow
to reestablish itself.
Hot and humid air funnels back into the region as a stiff
southwesterly low level jet pushes in. Hot h7 temperatures in the
+14C to +17C range will effectively cap the airmass for most of the
day. Highs should rebound back into the lower to middle 90s with
hottest air over west central/northwest MO and eastern KS. Add in
surface dewpoints in the 71F-74F range and HI values will likely top
out around 105F. So issued a heat advisory for afternoon hours.
Fast zonal flow across the northern tier of states will allow a fast
moving shortwave to force a cold front south and east into northwest
MO by very late afternoon. Hot h7 temperatures will hold back
convection but operational models "cooling" at h7 by 00z Tuesday
suggest cooling due to convection. While convection will likely hold
off until Monday night will transition to that with a small window
of slight chance PoPs over far northwest MO.
Monday night - Tuesday night:
Aforementioned cold front will be the focus for scattered convection
Monday evening. Moderate/extreme instability and 0-6km bulk shear of
30-35kt will support a severe threat across northern MO down to the
MO River.
This frontal boundary is expected to stall across central MO on
Tuesday then lift back north as a warm front. Thus this boundary
will once again be the focus for a third round of potential severe
weather Tuesday through Tuesday night. Should see a 10-15 degree
thermal contrast across the boundary. High precipitable water values
during this period will support a continued heavy rain threat as
some training of cells is possible.
Wednesday:
The warm front is expected to lift north into IA and allow the cap
to reform and give us a chance to dry out. But the hot and humid air
is the trade off.
Thursday - Saturday:
The bouncing front is expected to head back south during this period
and in the vicinity of the CWA such that moderately high PoPs are
required. Extensive cloud cover and the rain cooled air should bring
reasonably cool air to the region, but at a cost...high humidity and
the threat of heavy rains.
&&
.AVIATION...(For the 06Z TAFS through 06Z Monday Night)
Issued at 1123 PM CDT SUN JUN 21 2015
Overnight, low-level moisture could produce some IFR stratus over all
of the terminal sites. Ceiling heights may be further reduced,
depending on how well the stratus layer can maintain itself in light
of modest wind speeds. The primary impact for Monday afternoon will
be gusty winds out of the southwest. Daytime winds will sustain
around 15 knots gusting to 25-30kts during the afternoon hours.
Toward the end of the period, a cold front pushing through the region
from the north could lead to scattered convection Monday night. Winds
will continue to veer following the frontal passage, ultimately
transitioning out of the north while weakening.
&&
.EAX WATCHES/WARNINGS/ADVISORIES...
KS...HEAT ADVISORY from 1 PM to 7 PM CDT Monday FOR KSZ025-057-
102>105.
MO...HEAT ADVISORY from 1 PM to 7 PM CDT Monday FOR MOZ002>006-
011>015-020>023-028>031-037-038-043.
&&
$$
DISCUSSION...MJ
AVIATION...Welsh
AREA FORECAST DISCUSSION
NWS OMAHA/VALLEY NE
1005 PM CDT TUE JUN 23 2015
.UPDATE...
ISSUED AT 1005 PM CDT TUE JUN 23 2015
GOING FORECAST IN PRETTY GOOD SHAPE TONIGHT AND WE ARE ONLY MAKING
MINOR CHANGES TO TIMING OF PRECIP OVERNIGHT. EARLIER THIS EVENING
A FEW SHOWERS DEVELOPED OVER WRN IA AND THE 00Z KOAX SOUNDING
INDICATED THAT THESE WERE BASED AROUND 700 MB. THE CWA IS
CURRENTLY PRECIP FREE ATTM...BUT MODIFICATION OF THE SOUNDING
INDICATES WEAK INHIBITION BASED ON UPSTREAM MOISTURE PROFILES WITH
AROUND 1500 J/KG OF MUCAPE POSSIBLE. AS THE LOW LEVEL JET
INCREASES OVERNIGHT WE WILL LIKELY SEE AN INCREASED IN SHRA/TSRA
ACTIVITY ALONG THE H8 BOUNDARY OVER NE NEB SEWD INTO WESTERN IA.
SHORT TERM MODELS INDICATE THAT THIS IS LIKELY TO START TO HAPPEN
BETWEEN 06-08Z. SHEAR WITHIN THE CLOUD BEARING LAYER AND DEGREE OF
INSTABILITY DOESN`T RULE OUT AN ISO SVR STORM OVERNIGHT BUT ANY
COVERAGE OF SVR IS EXPECTED TO BE ISO. WILL INCREASE POPS NEAR THE
EXPECTED PLACEMENT OF THE BOUNDARY AFTER MIDNIGHT.
OTHERWISE WE WILL LIKELY SEE SOME CONVECTION CONT INTO WED
MRNG...EITHER MOVING IN FROM THE HIGH PLAINS OR CONTD IN
ASSOCIATION WITH LOWER-TROPOSPHERIC WAA AT THE NOSE OF THE LLJ.
THIS ACTIVITY WILL LIKELY SHIFT EWD AND/OR DISSIPATE BY MID TO
LATE MRNG OVER THE FA. THE NEW 00Z THEN DEPICTS A VOLATILE
ENVIRONMENT FOR SVR STORMS BY LATE AFTN WITH THE WARM
FRONT/OUTFLOW BOUNDARY LIFTING SLOWLY NWD THROUGH THE CWA. THE NAM
DOES REDEVELOP CONVECTION BY LATE AFTN ALONG THIS BOUNDARY BUT
SOME CAUTION SHOULD BE USED HERE. MODEL LOW-LEVEL MOISTURE
APPEARS HIGH WITH MID AND UPPER 70 DEW POINTS. MODIFICATION OF
POINT FORECAST SOUNDINGS WITH NEAR OR LOWER 70S DEW POINTS YIELDS
MUCH HIGHER MLCIN VALUES THAN MODEL PLANER FIELDS. THIS...ALONG
WITH THE EXPECTED STRONG EML OVERSPREADING THE AREA BY AFTERNOON
WITH H7 TEMPS OF 12-15 C MAKES CI HIGHLY UNCERTAIN. THE NAM AND
EARLIER GFS RUNS DO INDC A LOW-AMPLITUDE SHRTWV TROF AND
ASSOCIATED WEAK HEIGHT FALLS MOVG ACRS THE AREA DURING PEAK
HEATING...WHICH ALONG WITH SOME CONVERGENCE ALONG THE BOUNDARY MAY
HELP WITH CI. ALL THIS SAID THERE IS A GOOD DEAL OF UNCERTAINTY AS
TO CONVECTIVE EVOLUTION ON WED/WED NIGHT BUT THERE IS SOME THREAT
OF SIG SEVERE WEATHER GIVEN STORM INITIATION ON WED AFTN WITH ALL
MODES POSSIBLE IF STORMS DEVELOP.
&&
.SHORT TERM...(TONIGHT THROUGH FRIDAY)
ISSUED AT 257 PM CDT TUE JUN 23 2015
THUNDERSTORMS ARE MOVING ACROSS SOUTHEAST NEB THIS AFTERNOON.
SUBJECTIVE 12Z UPPER AIR ANALYSIS INDICATES BROAD UPPER-LEVEL HIGH
ACROSS THE SOUTHERN US...WITH SEASONALLY STRONG UPPER-LEVEL JET
ACROSS THE NORTHERN TIER FROM MT/DAKOTAS THROUGH THE GREAT LAKES TO
NORTHERN NEW ENGLAND. 850MB RIDGE WAS IN PLACE FROM EASTERN KS
THROUGH NEB INTO SD/SOUTHWESTERN ND. MOISTURE HAD BEEN SHUNTED
SOUTHWARD...WITH 8C+ DEWPOINTS FROM THE GREAT LAKES TO THE IA/MO
BORDER AND KS/NEB BORDER TOWARD SOUTHEASTERN NM. SURFACE HIGH AT
19Z WAS CENTERED IN IA/SOUTHEASTERN SD/SOUTHWESTERN MN.
MAIN FORECAST CONCERN IS CONVECTIVE POTENTIAL THROUGH THIS EVENING
AND LATER TONIGHT. SHORT-TERM MODELS ARE NOT HANDLING ONGOING
CONVECTION ALL THAT WELL...WITH MOST A LITTLE LATER ON DEVELOPMENT
THAN OCCURRED THIS AFTERNOON. RAP/NAM HAVE CAPTURED ONGOING
CONVECTION AND DO WEAKEN IT THROUGH THE AFTERNOON...AND HAVE
FOLLOWED THIS TREND AS CONVECTION SHOULD BE ENTERING A MORE HOSTILE
ENVIRONMENT. ONCE IT EXITS...MODEL CONSENSUS KEEPS AREA DRY THROUGH
MUCH OF THE EVENING...WITH CONVECTION BEGINNING TO DEVELOP SOMEWHERE
AROUND WEST CENTRAL IA INTO EAST CENTRAL/NORTHEAST NEB BY AROUND 06Z
ALONG THE 850MB BOUNDARY...ON THE NOSE OF INCREASING 850MB WINDS.
SOUTHERN CWA IS LIKELY TO AVOID CONVECTION...AND NORTHERNMOST CWA
MIGHT AS WELL...AND HAVE NARROWED BAND OF POPS TONIGHT. EVOLUTION
THROUGH THE DAY WEDNESDAY IS A LITTLE LESS CERTAIN...BUT SHOULD SEE
STORMS GENERALLY SHIFT NORTHWARD THROUGH THE DAY AS 850MB BOUNDARY
LIFTS...WITH SOME ARCING BACK INTO NORTHEAST TO CENTRAL NEB POSSIBLE.
FRONT SLIDES THROUGH THE CWA ON WEDNESDAY NIGHT/THURSDAY...AND HAVE
MAINTAINED LOW POPS IN THE SOUTHERN CWA. BY THURSDAY NIGHT...CWA
MAY BE IN A STUCK IN THE MIDDLE PATTERN...WITH CONVECTION ALONG THE
BOUNDARY IN KS/MO POSSIBLY JUST CLIPPING OUR SOUTHERNMOST CWA...AND
MORE NEBULOUS POTENTIAL FOR SHOWERS AND THUNDERSTORMS REACHING
NORTHEASTERN NEB AS CONVECTION ROLLS OFF THE HIGH PLAINS. HAVE
LOWERED POPS ACROSS MOST OF THE CWA IN BETWEEN THESE TWO AREAS...BUT
MAINTAINED A CHANCE ON FRIDAY AS CONVECTIVE REMNANTS AND/OR
REDEVELOPMENT ARE PROGGED IN EASTERN NEB.
.LONG TERM...(FRIDAY NIGHT THROUGH TUESDAY)
ISSUED AT 257 PM CDT TUE JUN 23 2015
UPPER-LEVEL TROUGH IS PROGGED TO DIG INTO THE GREAT LAKES...WITH
UPPER-LEVEL RIDGE TO THE WEST AND NORTH TO NORTHWEST FLOW OVER THE
CENTRAL PLAINS. GENERALLY NEAR TO BELOW NORMAL TEMPERATURES ARE
EXPECTED FROM THE END OF THE WORK WEEK...THROUGH THE WEEKEND...AND
INTO NEXT WEEK. CURRENT FORECAST IS LARGELY DRY FOR THE WEEKEND INTO
EARLY NEXT WEEK...THOUGH A HIT-OR-MISS SHOWER/THUNDERSTORM IS
POSSIBLE IN THE NORTHWEST FLOW.
&&
.AVIATION...(00Z TAFS FOR KOFK...KLNK AND KOMA.)
ISSUED AT 615 PM CDT TUE JUN 23 2015
VFR CONDITIONS THROUGH THE PERIOD...WITH CONVECTIVE DEVELOPMENT
THE PRIMARY CONCERN. A WARM FRONT WILL BE LIFTING NORTH TOWARD
THE AREA. LATEST HRRR MODEL SUGGESTS A FEW SHOWERS MAY TRY TO
DEVELOP NEAR KOMA 02-05Z. STRONG STORMS MAY DEVELOP FURTHER NORTH
AT KOFK BY 05-09Z. IF THESE DEVELOP...THEY MAY INITIALLY COULD BE
NORTH OF KOMA...BUT COULD THEN AFFECT KOMA BY 08-12Z. BELIEVE KLNK
WILL REMAIN DRY THROUGH THE PERIOD. THE FRONT DOES LIFT NORTH OF
KLNK/KOMA BY 15-16Z WHICH WILL BRING WINDS TO 170-190 KNOTS WITH
INCREASE IN SPEED TO 12 TO 18 KNOTS. FRONT ARRIVES AT KOFK BY 18Z.
POTENTIAL CONVECTIVE DEVELOPMENT MAY OCCUR WEDNESDAY
AFTERNOON...BUT NORTH OF THE TAF SITES.
&&
.OAX WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
IA...NONE.
&&
$$
UPDATE...BOUSTEAD
SHORT TERM...MAYES
LONG TERM...MAYES
AVIATION...DEWALD
AREA FORECAST DISCUSSION
NWS OMAHA/VALLEY NE
616 PM CDT TUE JUN 23 2015
.SHORT TERM...(TONIGHT THROUGH FRIDAY)
ISSUED AT 257 PM CDT TUE JUN 23 2015
THUNDERSTORMS ARE MOVING ACROSS SOUTHEAST NEB THIS AFTERNOON.
SUBJECTIVE 12Z UPPER AIR ANALYSIS INDICATES BROAD UPPER-LEVEL HIGH
ACROSS THE SOUTHERN US...WITH SEASONALLY STRONG UPPER-LEVEL JET
ACROSS THE NORTHERN TIER FROM MT/DAKOTAS THROUGH THE GREAT LAKES TO
NORTHERN NEW ENGLAND. 850MB RIDGE WAS IN PLACE FROM EASTERN KS
THROUGH NEB INTO SD/SOUTHWESTERN ND. MOISTURE HAD BEEN SHUNTED
SOUTHWARD...WITH 8C+ DEWPOINTS FROM THE GREAT LAKES TO THE IA/MO
BORDER AND KS/NEB BORDER TOWARD SOUTHEASTERN NM. SURFACE HIGH AT
19Z WAS CENTERED IN IA/SOUTHEASTERN SD/SOUTHWESTERN MN.
MAIN FORECAST CONCERN IS CONVECTIVE POTENTIAL THROUGH THIS EVENING
AND LATER TONIGHT. SHORT-TERM MODELS ARE NOT HANDLING ONGOING
CONVECTION ALL THAT WELL...WITH MOST A LITTLE LATER ON DEVELOPMENT
THAN OCCURRED THIS AFTERNOON. RAP/NAM HAVE CAPTURED ONGOING
CONVECTION AND DO WEAKEN IT THROUGH THE AFTERNOON...AND HAVE
FOLLOWED THIS TREND AS CONVECTION SHOULD BE ENTERING A MORE HOSTILE
ENVIRONMENT. ONCE IT EXITS...MODEL CONSENSUS KEEPS AREA DRY THROUGH
MUCH OF THE EVENING...WITH CONVECTION BEGINNING TO DEVELOP SOMEWHERE
AROUND WEST CENTRAL IA INTO EAST CENTRAL/NORTHEAST NEB BY AROUND 06Z
ALONG THE 850MB BOUNDARY...ON THE NOSE OF INCREASING 850MB WINDS.
SOUTHERN CWA IS LIKELY TO AVOID CONVECTION...AND NORTHERNMOST CWA
MIGHT AS WELL...AND HAVE NARROWED BAND OF POPS TONIGHT. EVOLUTION
THROUGH THE DAY WEDNESDAY IS A LITTLE LESS CERTAIN...BUT SHOULD SEE
STORMS GENERALLY SHIFT NORTHWARD THROUGH THE DAY AS 850MB BOUNDARY
LIFTS...WITH SOME ARCING BACK INTO NORTHEAST TO CENTRAL NEB POSSIBLE.
FRONT SLIDES THROUGH THE CWA ON WEDNESDAY NIGHT/THURSDAY...AND HAVE
MAINTAINED LOW POPS IN THE SOUTHERN CWA. BY THURSDAY NIGHT...CWA
MAY BE IN A STUCK IN THE MIDDLE PATTERN...WITH CONVECTION ALONG THE
BOUNDARY IN KS/MO POSSIBLY JUST CLIPPING OUR SOUTHERNMOST CWA...AND
MORE NEBULOUS POTENTIAL FOR SHOWERS AND THUNDERSTORMS REACHING
NORTHEASTERN NEB AS CONVECTION ROLLS OFF THE HIGH PLAINS. HAVE
LOWERED POPS ACROSS MOST OF THE CWA IN BETWEEN THESE TWO AREAS...BUT
MAINTAINED A CHANCE ON FRIDAY AS CONVECTIVE REMNANTS AND/OR
REDEVELOPMENT ARE PROGGED IN EASTERN NEB.
.LONG TERM...(FRIDAY NIGHT THROUGH TUESDAY)
ISSUED AT 257 PM CDT TUE JUN 23 2015
UPPER-LEVEL TROUGH IS PROGGED TO DIG INTO THE GREAT LAKES...WITH
UPPER-LEVEL RIDGE TO THE WEST AND NORTH TO NORTHWEST FLOW OVER THE
CENTRAL PLAINS. GENERALLY NEAR TO BELOW NORMAL TEMPERATURES ARE
EXPECTED FROM THE END OF THE WORK WEEK...THROUGH THE WEEKEND...AND
INTO NEXT WEEK. CURRENT FORECAST IS LARGELY DRY FOR THE WEEKEND INTO
EARLY NEXT WEEK...THOUGH A HIT-OR-MISS SHOWER/THUNDERSTORM IS
POSSIBLE IN THE NORTHWEST FLOW.
&&
.AVIATION...(00Z TAFS FOR KOFK...KLNK AND KOMA.)
ISSUED AT 615 PM CDT TUE JUN 23 2015
VFR CONDITIONS THROUGH THE PERIOD...WITH CONVECTIVE DEVELOPMENT
THE PRIMARY CONCERN. A WARM FRONT WILL BE LIFTING NORTH TOWARD
THE AREA. LATEST HRRR MODEL SUGGESTS A FEW SHOWERS MAY TRY TO
DEVELOP NEAR KOMA 02-05Z. STRONG STORMS MAY DEVELOP FURTHER NORTH
AT KOFK BY 05-09Z. IF THESE DEVELOP...THEY MAY INITIALLY COULD BE
NORTH OF KOMA...BUT COULD THEN AFFECT KOMA BY 08-12Z. BELIEVE KLNK
WILL REMAIN DRY THROUGH THE PERIOD. THE FRONT DOES LIFT NORTH OF
KLNK/KOMA BY 15-16Z WHICH WILL BRING WINDS TO 170-190 KNOTS WITH
INCREASE IN SPEED TO 12 TO 18 KNOTS. FRONT ARRIVES AT KOFK BY 18Z.
POTENTIAL CONVECTIVE DEVELOPMENT MAY OCCUR WEDNESDAY
AFTERNOON...BUT NORTH OF THE TAF SITES.
&&
.OAX WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
IA...NONE.
&&
$$
SHORT TERM...MAYES
LONG TERM...MAYES
AVIATION...DEWALD
AREA FORECAST DISCUSSION
NWS NORTH PLATTE NE
350 AM CDT MON JUN 22 2015
...CORRECTION FOR TYPO...
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 350 AM CDT MON JUN 22 2015
VERY STRONG CAP OVER WESTERN NEBRASKA TONIGHT AND SO FAR CONVECTION
IN THE DAKOTAS STAYING THERE. DEWPOINTS IN THE LOW 70S OVER MUCH OF
WESTERN NEBRASKA EARLY THIS MORNING. WITH STRATUS AND PATCHY FOG
BEGINNING TO DEVELOP OVER THE SANDHILLS WILL INCLUDE SOME IN THE
FORECAST WITH TEMPERATURE DEW POINT SPREADS JUST 1F-2F.
STRONG INVERSION THIS MORNING AND VERY UNSTABLE ATMOSPHERE. SURFACE
LOW PRESSURE 999MB OVER KVTN. COOL FRONT TRAILING WITH NORTH WINDS
OVER THE BLACK HILLS INTO SOUTHWEST SOUTH DAKOTA INTO NORTHEAST
WYOMING. FRONTAL BOUNDARY INTO NORTHWEST ZONES AROUND 11Z AND ACROSS
ALL OF WESTERN NEBRASKA BY 18Z. TIGHT PRESSURE GRADIENT WITH STRONG
NORTH WINDS AT 15 TO 25 MPH AND GUSTS INTO THE 30S OVER THE
SANDHILLS. COOLER TODAY WITH HIGHS IN THE UPPER 70S NORTHWEST AND
80S OVER THE REMAINDER OF THE FORECAST AREA. THE BIG CHANGE WILL BE
WITH DEW POINTS AS 70S MOVE SOUTH AND EAST AND 50S MOVE ACROSS THE
AREA.
CLEAR SKIES TONIGHT AND TEMPERATURES DROPPING INTO THE 50S AND 60S
FOR OVER NIGHT LOWS.
.LONG TERM...(TUESDAY THROUGH SUNDAY)
ISSUED AT 350 AM CDT MON JUN 22 2015
12Z TUESDAY AND BEYOND. ZONAL FLOW ALOFT WILL GRADUALLY GIVE WAY TO
NORTHWESTERLY ATOP THE CENTRAL PLAINS LATE WEEK AS A RIDGE BECOMES
FIRMLY ESTABLISHED ACROSS THE WESTERN CONUS...AND A LONGWAVE TROUGH
OVER THE EAST. THIS WILL FAVOR ISOLATED TO SCATTERED PRECIPITATION
CHANCES ACROSS THE HIGH PLAINS AND WEST CENTRAL NEBRASKA FROM
MID-WEEK INTO THE FIRST PART OF THE WEEKEND. FOR SUNDAY AND
BEYOND...THERE/S SUPPORT IN THE LONG RANGE SOLUTIONS OF THE RIDGE
EXPANDING EASTWARD...FOCUSING THE STORMS EAST OF THE FORECAST AREA.
TIMING OF INDIVIDUAL WAVES AND LOCATION OF A WAFFLING BAROCLINIC
ZONES HAS BEEN A RECENT CHALLENGE...WITH THE MODELS NOT ONLY AT ODDS
WITH EACH OTHER...BUT AT ODDS WITH EACH OF IT/S OWN SUCCESSIVE RUNS
AT TIMES. FORECAST CONFIDENCE IN CONVECTIVE DEVELOPMENT REMAINS
LOWER THAN AVERAGE...THUS A GENERAL BLEND OF THE AVAILABLE MEDIUM
RANGE MODELS WAS USED TO DERIVE THE LOCATIONS AND TIMING OF THE POP
FORECAST. AT THIS POINT THE GREATEST CHANCES OF POPS IN THE MEDIUM
RANGE APPEARS TO ARRIVE TUESDAY NIGHT AND INTO EARLY WEDNESDAY AS A
STRONG PV MAX MOVES EAST ACROSS THE DAKOTAS WHILE A WARM FRONT
RETURNS NORTH TO THE SANDHILLS. MODELS /GFS AND EC/ DIFFER ON THE
TIMING AND NORTHWARD ADVANCE OF THE FRONT AND INFLUENCE FROM THE PV
MAX...BUT AGREE ON A QUASI WEST TO EAST BAND OF QPF DEVELOPING OVER
THE CWA LATE TUESDAY/EARLY WEDNESDAY. WHERE THE FRONT SETS
UP...COUPLED WITH INCREASED UPPER FORCING...STORMS SHOULD BE
ISOLATED TO SCATTERED...BUT COULD BE SEVERE AS ENHANCED ZONAL FLOW
ALOFT NORTH OF THE LIFTING FRONT CONTRIBUTES 40-50KTS OF 0-6KM SHEAR
IN A MODERATELY UNSTABLE ATMOSPHERE. UPSCALE GROWTH IS POSSIBLE AS
A LLJ DEVELOPS OVERNIGHT.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT)
ISSUED AT 1110 PM CDT SUN JUN 21 2015
THE LATEST RUNS OF THE HRRR AND RAP MODELS SUGGEST SEVERE WEATHER
IS LIKELY ACROSS SD AND PERHAPS NRN NEB TONIGHT. IN GENERAL THE
MODELS HAVE BEEN TRENDING NORTH IN RESPONSE TO A STRONG 700 MB
CAP...WHICH COULD WEAKEN THOUGH. IF THIS HAPPENS THEN STORMS WOULD
BRUSH NRN NEB AND DEPART BY 12Z-13Z.
STRONG NORTH WINDS COULD DEVELOP BRIEFLY AS A COLD FRONT ACROSS
NERN WY MOVE THROUGH TOWARD MORNING. VFR IS EXPECTED ALL AREAS
THEREAFTER THROUGH MONDAY EVENING.
&&
.LBF WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...POWER
LONG TERM...JACOBS
AVIATION...CDC
AREA FORECAST DISCUSSION...UPDATED
NWS NORTH PLATTE NE
1110 PM CDT SUN JUN 21 2015
.SHORT TERM...(THIS EVENING THROUGH MONDAY)
ISSUED AT 328 PM CDT SUN JUN 21 2015
A WARM AND MUGGY AIRMASS IS IN PLACE THIS AFTERNOON IN THE PRESENCE
OF STRONG INSOLATION AND MOIST SOUTHEASTERLY FLOW. THIS HAS LED TO
THE DEVELOPMENT OF A VERY UNSTABLE BOUNDARY LAYER WITH SBCAPE VALUES
IN EXCESS OF 3000 J/KG. HOWEVER...A STOUT EML HAS EFFECTIVELY PUT A
LID ON ANY CONVECTIVE DEVELOPMENT. WITH WEAK UPPER LEVEL HEIGHT
RISES AND A LACK OF ANY WELL DEFINED BOUNDARY FOR INITIATION...NOT
ANTICIPATING THAT ANY SURFACE BASED PARCEL WILL BE ABLE TO BREAK THE
CAP TODAY AND CONFIDENCE TOO LOW TO INCLUDE ANY POP MENTION IN THE
GRIDS. BEST CHANCE FOR STORMS CONTINUES TO BE ACROSS OUR FAR
NORTHERN TIER COUNTIES AS AN UPPER LEVEL PV ANOMOLY TRACKS ACROSS
THE CANADIAN BORDER TONIGHT. A STRONG LOW LEVEL JET DEVLOPS LATER
THIS EVENING AND OVERNIGHT...OVERSPREADING A WARM FRONT DRAPED NEAR
TO JUST NORTH OF THE SD/NEB BORDER. DEEP CONVECTION WILL LIKELY MOVE
OUT OF THE HIGHER TERRAIN OF MT/WY THIS EVENING AND CONGEAL INTO AN
MCS AS IT FOLLOWS THE CONVERGENT NOSE OF THE LLJ AND TRACKS ACROSS
SOUTH DAKOTA...POSSIBLY GRAZING PARTS OF NORTHWEST AND NORTH CENTRAL
NEBRASKA. 50+ KTS OF DEEP LAYER SHEAR AND DRY MID-LEVELS WITH VERY
STEEP LAPSE RATES WILL PROMOTE A THREAT FOR DAMAGING WINDS...AND
POSSIBLE A FEW LARGE HAIL STONES...WITH ANY THUNDERSTORM ACTIVITY.
UPPER LEVEL PV KICKS EAST MONDAY...LEAVING THE CENTRAL/NORTHERN
PLAINS IN SYNOPTIC SCALE SUBSIDENCE WITH QG CONVERGENCE ALOFT. A
COLD FRONT TRACKS THROUGH THE CWA OVERNIGHT. BREEZY NORTHERLY WINDS
BEHIND THE FRONT WILL USHER IN SOME DRIER AIR AS COMPARED TO TODAY.
EXPECTING MOSTLY SUNNY SKIES WITH HIGHS IN THE UPPER 70S IN
NORTHWEST NEBRSAKA...TO NEAR 90 IN THE SOUTHWEST.
.LONG TERM...(MONDAY NIGHT THROUGH SUNDAY)
ISSUED AT 328 PM CDT SUN JUN 21 2015
AS DICUSSED PREVIOUSLY THE LARGE SCALE PATTERN TRANSITIONS TO A MORE
AMPLIFIED UPPER FLOW BY NEXT WEEKEND WITH A BUILDING RIDGE IN THE WRN
STATES AND LONG WAVE TROUGH IN THE EAST. BY THE END OF THE FORECAST
PERIOD...WESTERN AND NORTH CENTRAL NEBRASKA WILL BE INFLUENCED BY
FAST NWRLY FLOW ALOFT AND TEMPERATURES AT OR SLIGHTLY ABOVE AVERAGE
FOR THIS TIME OF YEAR.
FOR THE FIRST PART OF THE WEEK...ZONAL FLOW ALOFT WILL BRING QUICK
MOVING SHORT WAVE TROUGHS ACROSS THE NRN PLAINS. EACH ITERATION OF
THIS SCENARIO WILL DRAG AN ASSOCIATED COLD FRONT ACROSS THE AREA BUT
STALLING ACROSS THE CENTRAL HIGH PLAINS AS ASSOCIATED SFC PRESSURE
RISES REMAIN CLOSER TO THE UPPER FEATURES. HOWEVER...AS
THUNDERSTORMS DEVELOP IN ASSOCIATION WITH THE FRONT AND UPPER
FORCING...COLD POOL ORGANIZATION WILL ALSO SERVE TO ALTER THE MEAN
POSITION OF THE BOUNDARY WHICH MAKES THUNDERSTORM FORECASTS...AND
RESULTANT TEMPERATURE AND CLOUD FORECASTS...CHALLENGING.
MONDAY NIGHT...THE FRONT WILL HAVE CLEARED THE AREA AND RETURN
UPSLOPE FLOW WILL COMMENCE ACROSS THE PANHANDLE AND ADJACENT
PORTIONS OF THE WY/SD/CO HIGH PLAINS. THIS WILL KEEP LOW LEVEL
MOISTURE IN PLACE NORTH OF THE STALLED FRONT. SUBTLE PV ANOMALY IN
THE MODELS SHOULD WORK IN CONCERT WITH UPSLOPE FLOW AND ASSOCIATED
FORCING ALONG THE HIGHER TERRAIN TO GENERATE ISO TO SCT
THUNDERSTORMS MONDAY NIGHT WHICH WOULD EVENTUALLY MOVE INTO WRN
AREAS. ALSO OF CONCERN IS THE ACTUAL POSITION OF THE STALLED FRONT
NEAR THE NEB/KS BORDER AS A MORE SWD DISPLACED PV ANOMALY PROGRESSES TWD
THE SRN PLAINS BY TUES MORN. MODELS ARE INCONSISTENT IN DEVELOPMENT
OF PRECIPITATION ASSOCIATED WITH THIS LATTER SCENARIO AND THEREFORE
CONFIDENCE IS LOW. OF MORE CERTAINTY WILL BE THE POTENTIAL FOR LOW
CLOUDS NORTH OF THE STALLED FRONT WHICH WILL LIMIT INSOLATION
TUESDAY. AS NEXT AND POSSIBLY MORE SIGNIFICANT PV ANOMALY MOVES
ACROSS THE NRN ROCKIES TUES NIGHT...SFC PRESSURES LOWER ALONG THE
LEE SIDE AND IN RESPONSE SRLY WINDS INCREASE AND ALLOW THE
STATIONARY FRONT TO RETURN NWD AS A WARM FRONT. MODELS DIFFER AGAIN
ON ACTUAL POSITION AND GFS/NAM SUGGEST LOW PRESSURE DEVELOPING NERN
CO BY WED AFTERNOON. UPPER FORCING SHOULD BE SUFFICIENT TO ENCOURAGE
ENHANCED CONVERGENCE WHEREVER THE FRONT ENDS UP...HOWEVER
SIGNIFICANT DIFFS ALSO EXIST IN AMOUNT OF LOW LEVEL MOISTURE AND
RESULTANT INSTABILITY ACROSS THE AREA. HOWEVER...MODEL QPF IS NEARLY
NON-EXISTANT WHICH YIELDS TO LOW CONFIDENCE IN THE OVERALL EXTENDED
FCST...LEADING INTO THE LATTER HALF OF THE WEEK AS WELL.
BY THE END OF THE WEEK AND INTO THE FIRST OF THE WEEKEND
HOWEVER...MODEL CONSENSUS ON THE OVERALL PATTERN OF BUILDING RIDGE IN
THE WEST SHOULD ALLOW THE STORM TRACK TO BE BETTER DEFINED AND
SHOULD FOCUS MORE ACROSS THE HIGH PLAINS LEADING TO INCREASING
PRECIP CHANCES TWD THE WEEKEND. WITH INCREASINGLY NW FLOW
ALOFT...ANY ORGANIZED MCS DEVELOPMENT AND ASSOCIATED MOVEMENT WOULD
BE FAVORED TO BE MORE TWD WESTERN AND NORTH CENTRAL NEB.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT)
ISSUED AT 1110 PM CDT SUN JUN 21 2015
THE LATEST RUNS OF THE HRRR AND RAP MODELS SUGGEST SEVERE WEATHER
IS LIKELY ACROSS SD AND PERHAPS NRN NEB TONIGHT. IN GENERAL THE
MODELS HAVE BEEN TRENDING NORTH IN RESPONSE TO A STRONG 700 MB
CAP...WHICH COULD WEAKEN THOUGH. IF THIS HAPPENS THEN STORMS WOULD
BRUSH NRN NEB AND DEPART BY 12Z-13Z.
STRONG NORTH WINDS COULD DEVELOP BRIEFLY AS A COLD FRONT ACROSS
NERN WY MOVE THROUGH TOWARD MORNING. VFR IS EXPECTED ALL AREAS
THEREAFTER THROUGH MONDAY EVENING.
&&
.LBF WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...MARTIN
LONG TERM...JWS
AVIATION...CDC
AREA FORECAST DISCUSSION
NWS BUFFALO NY
754 PM EDT TUE JUN 23 2015
.SYNOPSIS...
A COLD FRONT WILL SAG SOUTH OF THE AREA THIS EVENING BRINGING DRIER
AIR AND CLEARING SKIES. GUSTY NORTHWESTERLY WINDS BEHIND THE
FRONT WILL DIMINISH THIS EVENING AS HIGH PRESSURE BUILDS INTO THE
GREAT LAKES. THE NEXT CHANCE FOR PRECIPITATION WILL COME THURSDAY
AS A STORM SYSTEM TRACKS JUST SOUTH OF NEW YORK.
&&
.NEAR TERM /THROUGH WEDNESDAY/...
THE COLD FRONT WHICH MOVED ACROSS THE REGION THIS AFTERNOON IS NOW
TO THE SOUTH OF THE CWA THIS EVENING. GUSTY NORTHWEST WINDS BEHIND
THIS FRONT WILL DIMINISH THIS EVENING AS HIGH PRESSURE BEGINS TO
RIDGE IN FROM OHIO. THIS WILL BRING IN A DRIER AND LESS MUGGY AIR.
MOSTLY CLEAR SKIES SHOULD RESULT IN DECENT RADIATIONAL COOLING
WITH OVERNIGHT LOWS IN THE 50S. NAM BUFKIT AND HRRR GUIDANCE SHOW
A FAIR AMOUNT OF LOW LEVEL MOISTURE AND PATCHY FOG IN THE
SOUTHERN TIER VALLEYS AND EAST OF LAKE ONTARIO CANNOT BE RULED OUT.
HOWEVER THE DRIER AIR SHOULD LIMIT FOG DEVELOPMENT.
ON WEDNESDAY...HIGH PRESSURE WILL CONTINUE TO BUILD INTO OHIO...WITH
LIGHTER WESTERLY WINDS IN PLACE ACROSS THE FORECAST AREA. EXPECT
LAKE BREEZES NORTHWEST OF BOTH LAKES ERIE AND ONTARIO... BRINING
SLIGHTLY COOLER TEMPERATURES TO THE BUFFALO / WATERTOWN AREA.
OVERALL... 850 MB TEMPERATURES REMAIN IN THE +11 TO +12 C
RANGE...AND WILL TRANSLATE TO HIGH TEMPERATURES IN THE 70S. WITH
LIGHT WINDS AND MOSTLY SUNNY SKIES...EXPECT A VERY PLEASANT DAY
ON WEDNESDAY.
&&
.SHORT TERM /WEDNESDAY NIGHT THROUGH THURSDAY NIGHT/...
ANY ISOLATED CONVECTION ACROSS THE SAINT LAWRENCE VALLEY
WEDNESDAY EVENING WILL END WITH THE LOSS OF DAYTIME HEATING AND
EXIT OF THE SURFACE AND MID LEVEL TROUGH. THIS WILL LEAVE MAINLY
DRY CONDITIONS OVERNIGHT AS THE WEAK OHIO VALLEY HIGH REMAINS IN
PLACE. WARM ADVECTION WILL INCREASE ACROSS WESTERN NY LATE
WEDNESDAY NIGHT WHICH WILL BRING INCREASING MID/HIGH CLOUDS.
ON THURSDAY...THE NEXT IN A PARADE OF MID LEVEL SHORTWAVES WILL MOVE
INTO THE WESTERN OHIO VALLEY WITH A WEAK SURFACE LOW TAKING A
SIMILAR TRACK. INCREASING WARM ADVECTION DOWNSTREAM OF THIS SYSTEM
WILL BRING AN INCREASING CHANCE OF A FEW SHOWERS TO WESTERN AND
CENTRAL NY...ESPECIALLY DURING THE AFTERNOON. ENOUGH INSTABILITY MAY
DEVELOP DURING THE AFTERNOON AND EVENING TO SUPPORT A FEW
THUNDERSTORMS AS WELL. THE SHOWER CHANCES WILL CONTINUE THURSDAY
NIGHT MAINLY ACROSS THE SOUTHERN HALF OF THE AREA AS WEAK WARM
ADVECTION CONTINUES IN THE MID LEVELS DOWNSTREAM OF THE OHIO VALLEY
LOW. A SURFACE RIDGE BUILDING INTO NORTHERN ONTARIO AND QUEBEC MAY
BRING ENOUGH OF A PUSH OF DRY AIR INTO THE NORTH COUNTRY TO KEEP
SHOWERS SOUTH OF THAT PORTION OF THE CWA.
A WAVE OF LOW PRESSURE WILL DEVELOP FRIDAY ALONG A BOUNDARY THAT
WILL RUN OVER THE OHIO VALLEY TO THE MID ATLANTIC STATES. IT APPEARS
SOME MOISTURE AND FORCING COULD SLIP FAR ENOUGH NORTH ACROSS THE
AREA FRIDAY AND FRIDAY NIGHT AND BRING AN INCREASING RISK FOR
SHOWERS...ESPECIALLY TO THE SOUTHERN HALF OF THE AREA.
&&
.LONG TERM /FRIDAY THROUGH TUESDAY/...
ZONAL FLOW ACROSS THE GREAT LAKES REGION WILL GIVE WAY TO A
DEVELOPING TROUGH DURING THIS PERIOD...THE RESULT OF AMPLIFICATION
OF THE RIDGE OVER THE WEST. THIS PATTERN WILL LIKELY LEAD TO BELOW
NORMAL TEMPERATURES AND INCREASING CHANCES FOR SHOWERS AND
THUNDERSTORMS. LATEST GUIDANCE SUGGEST THAT A DEVELOPING WAVE OF LOW
PRESSURE SPILLING DOWN THE BACK SIDE OF THE DEVELOP TROUGH ON
SATURDAY WILL TAKE FORM OVER OHIO. IT WILL THEN RIDE ALONG A STALLED
BOUNDARY EXTENDING FROM OHIO ACROSS THE MID ATLANTIC STATES. THIS
WILL LIKELY LEAD TO SOME SHOWER ACTIVITY...ALTHOUGH LOW LEVEL
NORTHEAST FLOW AND RELATIVELY COOL TEMPERATURES SHOULD LIMIT
INSTABILITY AND THE RISK FOR THUNDERSTORMS ON THE DAY SUNDAY. BEYOND
SUNDAY...THE NEXT SYSTEM LOOKS TO BRING A COLD FRONT CROSS THE
REGION SOMETIME TUESDAY. THIS SHOULD LEAD TO ANOTHER ROUND OF
SHOWERS AND THUNDERSTORMS AHEAD OF THE FRONT AND WITH ITS PASSAGE.
OVERALL...LOOK FOR HIGHS GENERALLY IN THE LOW 70S EACH DAY AND
OVERNIGHT LOWS IN THE 50S.
&&
.AVIATION /00Z WEDNESDAY THROUGH SUNDAY/...
FOR THE MOST PART EXPECT VFR CONDITIONS THROUGH THE 00Z TAF CYCLE
THROUGH 00Z THURSDAY. THERE IS A SMALL POTENTIAL FOR FOG AND/OR
LOW CIGS FROM LOW LEVEL MOISTURE TRAPPED BENEATH AN INVERSION AS
HIGH PRESSURE BUILDS IN TONIGHT. THE BEST CHANCE FOR THIS IS AT
JHW/ART...WITH BUF/ROC/IAG LIKELY TO REMAIN VFR THROUGHOUT THE
NIGHT. EXPECT WIDESPREAD VFR CONDITIONS WEDNESDAY AS SURFACE HIGH
PRESSURE BUILDS IN.
OUTLOOK...
THURSDAY THROUGH SUNDAY...MAINLY VFR WITH A CHANCE OF SHOWERS.
&&
.MARINE...
NORTHWESTERLY WINDS WILL CONTINUE TO DIMINISH THIS EVENING AS HIGH
PRESSURE RIDGES FROM THE OHIO VALLEY ACROSS THE LOWER LAKES. THIS
WILL ALLOW SMALL CRAFT ADVISORY HEADLINES TO BE DROPPED FROM W-E
THIS EVENING. OTHERWISE...WINDS WILL BECOME LIGHT AND MORE
WESTERLY OVERNIGHT AND INTO WEDNESDAY AS HIGH PRESSURE CONTINUES
TO BUILD OVER OHIO.
&&
.BUF WATCHES/WARNINGS/ADVISORIES...
NY...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 11 PM EDT THIS EVENING FOR
LOZ043>045.
&&
$$
SYNOPSIS...APFFEL/CHURCH
NEAR TERM...APFFEL/CHURCH
SHORT TERM...FRANKLIN
LONG TERM...AR
AVIATION...APFFEL
MARINE...APFFEL/CHURCH
AREA FORECAST DISCUSSION
NWS RALEIGH NC
619 PM EDT MON JUN 22 2015
.SYNOPSIS...WEST TO NORTHWEST FLOW ALOFT WILL PREVAIL ACROSS THE
REGION THROUGH MID-WEEK...ON THE NORTHEAST PERIPHERY OF AN UPPER
LEVLE RIDGE CENTERED OVER THE LOWER MIDWEST AND LOWER MISSISSIPPI
RIVER VALLEY.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 615 PM MONDAY...
CENTRAL NC REMAINS WITHIN A LOW-LEVEL MOISTURE MINIMUM THIS
AFTERNOON...AS INDICATED BY 925-850 MB DEWPOINTS ~14C (PER SPC
MESOANALYSIS)...AND AS ONE MIGHT INFER GIVEN WEAK/MODEST MID-LEVEL
LAPSE RATES (NO SIGNIFICANT CAP) AND A LACK OF DIURNAL CU. AS A
RESULT...INSTABILITY IS WEAKER AND CONVECTIVE INHIBITION IS GREATER
THAN IN SURROUNDING AREAS...AND IT IS UNLIKELY THAT CONVECTION WILL
DEVELOP WITHIN CENTRAL NC THE REMAINDER OF THE AFTERNOON.
AN MCV WAS NOTED UPSTREAM OVER SOUTHEAST KY AT 21Z THIS AFTERNOON.
THE LATEST RAP GUIDANCE INDICATES THIS FEATURE WILL TRACK SLOWLY ESE
INTO SOUTHWEST VA BY ~00Z...SOUTHEASTWARD TO BOONE NC BY ~03Z...
SSE/SOUTHWARD TO MORGANTON BY ~06Z AND CHARLOTTE BY ~09Z. IT IS
POSSIBLE THAT DPVA ASSOCIATED WITH THIS FEATURE COULD PROVIDE
SUFFICIENT FORCING TO AID CONVECTIVE DEVELOPMENT IN NORTHWEST NC
AFTER 00Z...WITH PROPAGATION INTO THE TRIAD/NW PIEDMONT POSSIBLE BY
~03Z. IT SHOULD BE NOTED THAT NONE OF THE 12Z CAMS SUPPORT SUCH
DEVELOPMENT...PROBABLY DUE TO UNFAVORABLE DIURNAL TIMING AND A
DRIER/LESS SUPPORTIVE CONVECTIVE ENVIRONMENT...ASSUMING NO
SIGNIFICANT LOW-LEVEL MOISTURE RECOVERY AFTER SUNSET. SHOULD
CONVECTION DEVELOP OR PROPAGATE INTO THE TRIAD...DCAPE VALUES
RANGING FROM 1000-1200 J/KG SUGGESTS ROBUST DOWNDRAFTS/COLD POOLS
AND AN ATTENDANT POTENTIAL FOR DAMAGING WINDS...THOUGH DEEP LAYER
SHEAR WILL BE MARGINALLY SUPPORTIVE OF MULTICELLULAR ORGANIZATION
(AT BEST). -VINCENT
&&
.SHORT TERM /TUESDAY AND TUESDAY NIGHT/...
AS OF 240 PM MONDAY...
THE SUB-TROPICAL RIDGE WILL STRENGTHEN TO 325-326 DM OVER THE MID-
SOUTH ON TUE...WITH AN ASSOCIATED UPTICK IN DOWNSTREAM LOW LEVEL
THICKNESS VALUES AOA 1440 METERS OVER CENTRAL NC. HIGH TEMPERATURES
ARE CONSEQUENTLY EXPECTED TO REACH THE UPPER 90S TO AROUND 100
DEGREES...LIKELY THE HOTTEST DAY OF THE WEEK. MODEL GUIDANCE
SUGGESTS SFC DEWPOINTS WILL NOT MIX OUT AS MUCH AS PREVIOUS
DAYS...AT LEAST NOT IN THE COASTAL PLAIN AND EASTERN SANDHILLS...
WHERE AOA 70 DEGREES IS EXPECTED. AS SUCH...HEAT INDEX VALUES ARE
FORECAST AROUND 105 DEGREES OR SO DURING THE AFTERNOON; AND ANOTHER
HEAT ADVISORY HAS BEEN ISSUED FOR THE AREAS GENERALLY ALONG AND EAST
OF INTERSTATE 95.
SINCE THE PRIMARY FRONT...LIKELY A CONVECTIVELY-MODULATED ONE WILL
REMAIN NORTH OF THE VA/NC BORDER THROUGH AT LEAST 12Z WED...FORCING
AT THIS LATITUDE WILL NEED TO COME FROM OUTFLOW AND/OR AN MCV FROM
UPSTREAM CONVECTION...NEITHER OF WHICH CAN BE FORECAST WITH MUCH
CONFIDENCE AT THIS TIME RANGE. POP WILL CONSEQUENTLY BE KEPT IN THE
SLIGHT TO LOW CHANCE RANGE...WITH THE RELATIVE BEST CHANCE ACROSS
THE NORTHERN PIEDMONT LATE IN THE AFTERNOON AND EARLY EVENING GIVEN
THE ORIENTATION OF THE RIDGE TO THE SOUTH AND ASSOCIATED TRACK OF
MCS/S ACROSS THE TN VALLEY-CENTRAL APPALACHIANS.
&&
.LONG TERM /WEDNESDAY THROUGH MONDAY/...
AS OF 315 PM MONDAY...
WED/WED NIGHT: THE EXTENDED PERIOD WILL START WITH THE UPPER LEVEL
HIGH CENTERED OVER THE MID-MS RIVER VALLEY AND THE UPPER LEVEL LOW
OVER NE CANADA. CENTRAL NC WILL BE SANDWICHED IN BETWEEN THE
TWO...WITH GENERALLY NW FLOW ALOFT. THE RIDGE WILL WEAKEN THROUGHOUT
THE DAY...WITH INCREASING CHANCES FOR CONVECTION AS THE TROUGH
PUSHES SOUTHWARD. MEANWHILE...A SURFACE BACKDOOR COLD FRONT WILL
SLIDE SOUTH... STALLING OUT AROUND THE NC/VA BORDER BY LATE WED
AFT/EVE. HIGHS WILL GENERALLY BE IN THE MID TO UPPER 90S NORTH TO
SOUTH. OVERNIGHT LOWS IN THE LOW TO MID 70S.
THROUGH THE WEEKEND: FOR THE REMAINDER OF THE EXTENDED...THE SURFACE
FRONT WILL LIFT NORTHWARD AND PUSH SOUTHWARD AS A LOW SLOWLY
DEVELOPS OVER THE UPPER MIDWEST. THE NEARLY ZONAL FLOW ALOFT WITH A
S/W OR TWO WILL GRADUALLY BECOME A MORE AMPLIFIED TROUGH LATE IN THE
WEEK... PROGRESSING INTO THE EASTERN U.S. LATE IN THE WEEK AND OVER
THE WEEKEND. CONFIDENCE REGARDING CONVECTIVE CHANCES/TIMING/COVERAGE
IS NOT TERRIBLY HIGH AT THIS TIME...HOWEVER THERE IS AT LEAST A
CHANCE FOR SHOWERS/STORMS NEARLY EVERY DAY. HIGHS WILL GENERALLY BE
IN THE MID 90S THROUGH FRIDAY...WITH THE INDICATION IN THE MODELS OF
A COOLING TREND OVER THE WEEKEND. HIGHS SAT IN THE UPPER 80S TO LOW
90S. LOWS WILL FOLLOW A SIMILAR TREND... DECREASING INTO THE UPPER
60S TO MID 70S BY FRI NIGHT.
SATURDAY NIGHT ONWARD: THE MODELS ARE CONSISTENTLY INDICATING COOL
SURFACE HIGH PRESSURE RIDGING INTO CENTRAL NC FROM THE NORTHEAST BY
SUNDAY...WHICH WOULD RESULT IN COOLER TEMPERATURES ACROSS THE
REGION. ALTHOUGH NOT TERRIBLY CONFIDENT...HIGHS SUNDAY COULD BE IN
THE MID TO UPPER 80S...WITH LOWS IN THE MID 60S TO LOW 70S.
&&
.AVIATION /18Z MONDAY THROUGH SATURDAY/...
AS OF 155 PM MONDAY...
VFR CONDITIONS ARE GENERALLY EXPECTED UNDER THE INFLUENCE OF SUB-
TROPICAL HIGH PRESSURE OVER THE SOUTHEAST STATES. THE EXCEPTION WILL
BE IN SHOWERS AND STORMS WHOSE PROBABILITY OF OCCURRENCE WILL BE
RELATIVELY LOW (~20 PERCENT) UNTIL A CONVECTIVE OUTFLOW-MODULATED
FRONT SETTLES SOUTH INTO VA-NC ON WED AND SUPPORTS A BETTER CHANCE
(30-50 PERCENT) AT THAT TIME. AFTER THE FRONT BRIEFLY RETREATS NORTH
OF OUR AREA ON THU...THE PROBABILITY OF SHOWERS AND STORMS WILL
FURTHER INCREASE WHEN THE FRONT SETTLES SOUTH AND STALLS OVER NC FRI
THROUGH THE WEEKEND. SOME SUB-VFR CEILINGS EVEN OUTSIDE OF
CONVECTION WILL ALSO BE POSSIBLE AT THAT TIME.
&&
.CLIMATE...
REC
DAY MAX YR
RDU RECORDS
06/22 100 1981
06/23 100 1986
06/24 99 2010
GSO RECORDS
06/22 100 1914
06/23 102 1914
06/24 103 1914
FAY RECORDS
06/22 101 1990
06/23 102 1981
06/24 102 1914
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
HEAT ADVISORY UNTIL 7 PM EDT THIS EVENING FOR NCZ027-028-042-
043-077-078-085-086-088-089.
&&
$$
SYNOPSIS...VINCENT
NEAR TERM...VINCENT
SHORT TERM...26
LONG TERM...RAH
AVIATION...26
CLIMATE...RAH
AREA FORECAST DISCUSSION
NWS NEWPORT/MOREHEAD CITY NC
1256 PM EDT MON JUN 22 2015
.SYNOPSIS...
A WEAK FRONT WILL PASS THROUGH THE NORTHEAST CORNER OF THE STATE
TODAY. ANOTHER FRONT WILL MOVE IN ON WEDNESDAY AND BECOME
STATIONARY ACROSS THE REGION THROUGH SATURDAY. IT WILL THEN LIFT
NORTH AS A WARM FRONT SUNDAY.
&&
.NEAR TERM /TODAY/...
AS OF 1250 PM MON...BERMUDA HIGH REMAINS IN PLACE WITH A VERY
WARM AND HUMID AIRMASS. NO SIG CHANGES NEEDED TO PREVIOUS FORECAST
FOR UPDATE. LOW LEVEL THICKNESS VALUES AND 850MB TEMPS 19-20C
SUPPORT HIGHS IN THE 90S TODAY...UPPER MID/UPPER 90S INLAND. HEAT
INDEX TEMPS IN THE ADVISORY RANGE AND WILL CONTINUE THE ADVISORY
FOR ALL BUT THE OUTER BANKS...FOR HEAT INDEX VALUES 105-109 THIS
AFTERNOON. THOUGH NOW SEEMS TO BE MORE MARGINAL FOR THE COASTAL
PLAIN WITH DEWPOINTS AROUND 70. WEAK FRONTAL BOUNDARY...CURRENTLY
ANALYZED OVER SE VA...WILL PASS THROUGH THE NORTHEAST PORTION OF
THE STATE TODAY. THAT AND THE SEABREEZE WILL BE ENOUGH TO CONTINUE
SLIGHT CHANCE POPS THIS AFTERNOON AND EARLY EVENING. HRRR AND NSSL
WRF SHOW ISOLATED TO WIDELY SCATTERED CONVECTION DEVELOPING THIS
AFTERNOON. AN ISOLATED STRONG THUNDERSTORM WITH GUSTY WINDS WILL
BE POSSIBLE.
&&
.SHORT TERM /TONIGHT/...
AS OF 3 AM MON...WEAK DYNAMICS FOR CONVECTION SO ANYTHING THAT
DEVELOPS WILL DISSIPATE QUICKLY THIS EVENING WITH THE LOSS OF
DAYTIME HEATING. WARM AND MUGGY OVERNIGHT WITH LOWS IN THE UPPER
70S TO LOWER 80S.
&&
.LONG TERM /TUESDAY THROUGH SUNDAY/...
AS OF 330 AM MONDAY...HEAT AND HUMIDITY WILL START THE WEEK BUT
BETTER CHANCES OF RAINFALL AND SLIGHTLY COOLER WEATHER RETURNS FOR
MID TO LATE WEEK.
TUESDAY/TUESDAY NIGHT...TUESDAY SHOULD BE THE HOTTEST DAY OF THE
WEEK AS RISING UPPER HEIGHTS WILL COMBINE WITH A MOIST SW FLOW TO
PUSH HIGH TEMPERATURES INTO THE UPPER 90S INLAND WITH LOWER 90S
COAST WITH HEAT INDICES OVER 105 DEGREES. RAIN CHANCES WILL BE
MINIMAL TUESDAY...MAINLY WITH THE SEA BREEZE OVER INLAND SOUTHERN
SECTIONS OF THE CWA.
WEDNESDAY/WEDNESDAY NIGHT...WEAK BACK DOOR FRONT DROPS INTO THE
AREA LATE WEDNESDAY NIGHT. CONVERGENCE AHEAD OF THE FRONT WILL
LEAD TO A CHANCE OF SHOWERS/THUNDERSTORMS DURING THE
AFTERNOON...GREATEST CHANCES OVER THE NORTHERN CWA. AS UPPER
HEIGHTS FALL AND SEVERAL MID-LEVEL SHORTWAVES CROSS THE AREA IN
THE NORTHWEST FLOW ALOFT...WILL CONTINUE THE RAIN CHANCES THROUGH
WEDNESDAY NIGHT. THE FRONT STALLS AND EVENTUALLY WASHES OUT BY
EARLY THURSDAY.
THURSDAY/THURSDAY NIGHT...WITH A CONTINUED MOIST SOUTHWEST FLOW
AND LOWERING MID-LEVEL HEIGHTS...WILL HAVE INCREASED CLOUD COVER
AND BETTER CHANCES OF SHOWERS/THUNDERSTORMS THURSDAY AND THURSDAY
NIGHT. HIGH TEMPERATURES WILL STILL REACH THE LOW/MID 90S...BUT
NIGHTTIME TEMPERATURES WILL BE COOLER WITH AREAS OF RAIN-COOLED
AIR.
FRIDAY THROUGH SUNDAY...AN UNSETTLED PATTERN CONTINUES FOR FRIDAY
THROUGH NEXT WEEKEND WITH THE COMBINATION OF FALLING UPPER LEVEL
HEIGHTS AND A MOIST SOUTHWEST FLOW WITH A WEAK FRONTAL BOUNDARY
STALLING NEAR THE REGION. WILL KEEP CHANCE POPS IN THE FORECAST
FOR SCATTERED SHOWERS/THUNDERSTORMS AT MOST ANYTIME THROUGH THE
PERIOD. THANKFULLY...TEMPERATURES WILL BE A BIT COOLER...WITH
HIGHS GENERALLY UPPER 80S TO LOWER 90S AND LOWS IN THE LOW/MID
70S.
&&
.AVIATION /18Z MONDAY THROUGH SATURDAY/...
SHORT TERM /THROUGH TUESDAY/...
AS OF 1250 PM MON...PRED VFR CONDITIONS EXPECTED THROUGH THE
PERIOD. ISOLATED TO WIDELY SCT SEABREEZE CONVECTION EXPECTED THIS
AFTERNOON. WITH LITTLE CHANGE TO AIRMASS...WILL FOLLOW
PERSISTENCE AND INCLUDE MVFR FOG IN OAJ OVERNIGHT AND EARLY
TUESDAY MORNING. SW WIND GUSTS TO 15-20KT TUE AFTERNOON.
LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/...
AS OF 345 AM MONDAY...GENERALLY VFR CONDITIONS ARE EXPECTED FOR
MOST OF THE EXTENDED PERIOD. SCATTERED SHOWERS/THUNDERSTORMS MAY
BRIEFLY REDUCE CONDITIONS TO MVFR. IN AREAS THAT DO RECEIVE
RAINFALL...PATCHES OF LATE NIGHT FOG AND STRATUS MAY ALSO BRIEFLY
REDUCE CONDITIONS TO MVFR AND PERHAPS TO IFR THROUGH THE PERIOD.
&&
.MARINE...
SHORT TERM /THROUGH TONIGHT/...
AS OF 1250 PM MON...LATEST OBS SHOW VARIABLE WINDS ACROSS THE
WATERS AS WEAK BOUNDARY OVER SE VA CONTINUES TO SLOWLY MOVE
SOUTHWARD. N/NE WINDS 5-10KT ACROSS THE SOUNDS AND NORTHERN
WATERS...AND WSW/SW WINDS 5-15KT SOUTH...WITH SEAS 2-4FT. BERMUDA
HIGH REMAINS THE MAIN FEATURE. WIND DIRECTIONS WILL CONTINUE TO BE
TRICKY TODAY AS BOUNDARY SAGS SOUTH...LIGHTER WINDS ACROSS THE
NORTH AND SLIGHTLY STRONGER IN THE SOUTHERN WATERS. BOUNDARY IS
EXPECTED TO WASH OUT/LIFT BACK TO THE NORTH TONIGHT WITH WINDS
RETURNING S/SW ACROSS ALL WATERS BY LATE TONIGHT...AS SEAS
CONTINUE AT 2-4FT.
LONG TERM /TUESDAY THROUGH FRIDAY/...
AS OF 350 AM MONDAY...SOUTHWEST WINDS WILL BECOME GUSTY DURING THE
AFTERNOON AND EVENING ON TUESDAY WITH THE GRADIENT BETWEEN INLAND
TROUGH AND HIGH PRESSURE OFFSHORE. WILL SEE SOME 15 TO 20 KNOT
WINDS WITH SEAS BUILDING TO 3 TO 5 FEET...ESPECIALLY OVER THE
CENTRAL WATERS. A WEAK BACK DOOR COLD FRONT WILL DROP INTO THE
WATERS WEDNESDAY AND WEDNESDAY NIGHT BUT WILL QUICKLY WASH OUT
WITH A S/SW WIND FLOW RESUMING BY EARLY THURSDAY. SOUTHWEST
GRADIENT AGAIN INCREASES BEHIND SURFACE LOW MOVES ACROSS VIRGINIA
AND HIGH OFFSHORE THURSDAY NIGHT AND ESPECIALLY FRIDAY WITH THE
LATEST WAVE MODELS SHOWING SEAS BUILDING TO AS HIGH AS 6 TO 7 FEET
BY FRIDAY WITH SMALL CRAFT ADVISORIES LIKELY BY THIS TIME.
&&
.CLIMATE...
RECORD HIGH TEMPERATURES MONDAY: 6/22
LOCATION-----TEMP/YEAR--NOTES
NEW BERN 97/1994 (KEWN ASOS)
HATTERAS 92/1994 (KHSE ASOS)
GREENVILLE 102/1933 (COOP - NOT KPGV ASOS)
MOREHEAD CITY 94/1994 (COOP - NOT KMRH ASOS)
KINSTON 100/1952 (COOP - NOT KISO ASOS)
JACKSONVILLE 100/1981 (KNCA AWOS)
RECORD HIGH TEMPERATURES TUESDAY: 6/23
LOCATION-----TEMP/YEAR--NOTES
NEW BERN 98/1988 (KEWN ASOS)
HATTERAS 88/1996 (KHSE ASOS)
GREENVILLE 100/1933 (COOP - NOT KPGV ASOS)
MOREHEAD CITY 95/1988 (COOP - NOT KMRH ASOS)
KINSTON 102/1911 (COOP - NOT KISO ASOS)
JACKSONVILLE 99/2010 (KNCA AWOS)
&&
.MHX WATCHES/WARNINGS/ADVISORIES...
NC...HEAT ADVISORY UNTIL 8 PM EDT THIS EVENING FOR NCZ029-044>047-
079>081-090>095-098.
MARINE...NONE.
&&
$$
SYNOPSIS...HSA
NEAR TERM...CQD/HSA
SHORT TERM...HSA
LONG TERM...CTC
AVIATION...CTC/CQD
MARINE...CTC/CQD/HSA
CLIMATE...MHX
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
1220 PM EDT MON JUN 22 2015
.SYNOPSIS...
HIGH HEAT AND HUMIDITY WILL CONTINUE THROUGH AT LEAST THE MIDDLE
OF THE WEEK...WITH ISOLATED SHOWERS AND THUNDERSTORMS DURING THE
AFTERNOONS AND EVENINGS. SLIGHTLY COOLER TEMPERATURES ALONG WITH A
BETTER CHANCE OF SHOWERS AND THUNDERSTORMS WILL DEVELOP THIS
WEEKEND.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 1030 AM MONDAY...HOT WEATHER CONTINUES WITH WELL ABOVE
NORMAL TEMPERATURES COMBINING WITH HIGH HUMIDITY TO CREATE
POTENTIALLY DANGEROUS HEAT INDICES VALUES TODAY. A HEAT ADVISORY
WILL REMAIN IN EFFECT FOR ALL COUNTIES FROM LATE THIS MORNING AND
INTO THE EVENING HOURS...WITH HEAT INDEX VALUES RANGING FROM 104F
TO 109F DURING THOSE TIMES. ACTUAL TEMPERATURES WILL RANGE FROM
THE LOWER 90S NEAR THE BEACHES TO AROUND 100 WELL INLAND.
HIGH PRESSURE OFFSHORE IN COMBINATION WITH A THERMAL TROUGH INLAND
WILL CONTINUE A LIGHT AND MOIST SOUTHWESTERLY FLOW THAT WILL KEEP
DEWPOINTS ELEVATED FROM THE UPPER 60S TO MID 70S. THE UPPER RIDGE
BEGINS TO RE-STRENGTHEN DURING THIS PERIOD...AND THIS WILL HELP TO
SUPPRESS WIDESPREAD CONVECTION DESPITE AN UNSTABLE ATMOSPHERE AND
STEEP LOW LEVEL LAPSE RATES. HOWEVER...WITH SUCH STRONG SURFACE
HEATING WE CAN EXPECT ISOLATED TO WIDELY SCATTERED CONVECTION
CONCENTRATED ALONG THE SEA BREEZE FRONT THIS AFTERNOON AND
EVENING. HRRR SHOWS VERY ISOLATED ACTIVITY ALONG SEA BREEZE THIS
AFTERNOON. THE STEERING FLOW IS VERY WEAK AND THEREFORE ANY
SHOWERS WILL POP UP AND DIE FAIRLY RAPIDLY POSSIBLY PUTTING DOWN A
QUICK DOWNPOUR. OVERALL EXPECTING PLENTY OF SUNSHINE AND
POTENTIALLY DANGEROUS HEAT.
&&
.SHORT TERM /TUESDAY THROUGH WEDNESDAY NIGHT/...
AS OF 300 AM MONDAY...THE MID LEVEL FLOW/PATTERN WILL FEATURE A SUBTLE
NORTHWEST FLOW WITH 500MB HEIGHTS REMAINING AROUND 593-594DM. THIS
WILL KEEP THE VERY WARM TEMPERATURES IN PLACE THROUGH THE PERIOD.
EXCESSIVE HEAT WARNINGS REMAIN A POSSIBILITY EACH DAY BUT MORE
LIKELY THE CONTINUATION OF THE HEAT ADVISORY WILL SUFFICE. EXPECT
HIGHS TO ECLIPSE TRIPLE DIGITS INLAND WITH UPPER 90S ALONG THE
COAST. SOUNDINGS DO SHOW A SLIGHTLY BETTER CHANCE FOR CONVECTION
WEDNESDAY BUT OVERALL COVERAGE WILL REMAIN LIMITED.
&&
.LONG TERM /THURSDAY THROUGH SUNDAY/...
AS OF 300 AM MONDAY...THE BIG STORY REMAINS THE PATTERN CHANGE EXPECTED TO
OCCUR IN THE SECOND HALF OF THE PERIOD AS MID LEVEL TROUGHING
DEVELOPS OVER THE TENNESSEE VALLEY TO SOME DEGREE. THIS WILL BRING A
PROLONGED PERIOD OF A GOOD CHANCE OF SHOWERS AND THUNDERSTORMS ALONG
WITH TEMPERATURES EXPECTED TO TREND TOWARD CLIMATOLOGY. THE HIGHEST
POPS CURRENTLY ARE FOR SATURDAY WITH HIGH CHANCE VALUES. EITHER SIDE
OF THIS POPS ARE IN THE CHANCE RANGE WITH MORE OF A DIURNAL NATURE.
TEMPERATURES REMAIN ON THE VERY WARM SIDE THURSDAY AND FRIDAY. WITH
THE ADDED CONVECTION AND LOWER HEIGHTS...READINGS SCALE BACK
SOMEWHAT FOR THE WEEKEND.
&&
.AVIATION /18Z MONDAY THROUGH SATURDAY/...
AS OF 17Z...TERMINALS CONTINUE TO BE VFR THIS EARLY AFTERNOON.
EXPECT TYPICAL SUMMER WEATHER PATTERN WITH LIGHT SW-W WINDS...EXCEPT
BECOMING S-SSW AT THE COASTAL TERMINALS BY EARLY AFTERNOON AS THE SEA
BREEZE DEVELOPS AND MOVES INLAND. MOISTURE IS LACKING BUT GIVEN THE
INSTABILITY ISOLATED THUNDERSTORMS SHOULD DEVELOP ALONG THE SEA BREEZE
BOUNDARY AND ALONG THE PIEDMONT TROUGH INLAND. BEST TIME FRAME FOR VCTS
AT THE COASTAL TERMINALS WILL BE 18-21Z OR UNTIL THE SEA BREEZE BOUNDARY
MOVES FAR ENOUGH INLAND...AND INLAND TERMINALS 20-24Z. CONVECTION
DISSIPATES THIS EVENING WITH LIGHT SW WINDS CONTINUING THROUGH THE NIGHT.
VFR CONDITIONS WILL CONTINUE THROUGHOUT THE OVERNIGHT PERIOD AND THROUGH
23/18Z WITH DRY ATMOSPHERE DO NOT EXPECT VSBY TO DROP TO MVFR.
EXTENDED OUTLOOK...CHANCE OF SHOWERS/THUNDERSTORMS TUE-SAT WITH
MAINLY VFR.
&&
.MARINE...
NEAR TERM /THROUGH TONIGHT/...
AS OF 1030 AM MONDAY...LIGHT SOUTHWEST FLOW AROUND ATLANTIC HIGH
PRESSURE WILL CONTINUE THROUGH TONIGHT. WINDS WILL SPIKE UP
BECOMING GUSTY AS THEY BACK SLIGHTLY IN A SLIGHTLY TIGHTER
GRADIENT THIS AFTERNOON BETWEEN THERMAL TROUGH INLAND AND HIGH
OFF SHORE. OVERALL EXPECT SW WINDS 10 TO 15 KTS. SEAS UP AROUND 3
TO 4 FT IN A STRONGER SOUTHERLY PUSH YESTERDAY WILL SUBSIDE DOWN
TO 2 TO 3 FT BY TONIGHT. EXPECT CHOPPIER SEAS IN SEA BREEZE
THROUGH THIS AFTERNOON.
SHORT TERM /TUESDAY THROUGH WEDNESDAY NIGHT/...
AS OF 300 AM MONDAY...SOUTHWEST WINDS OF 10-15 KNOTS WILL PREVAIL
ACROSS THE COASTAL WATERS THROUGH THE PERIOD. THERE WILL BE SOME
BACKING OF THE WIND DIRECTION ALONG THE COAST DURING THE AFTERNOON
HOURS WITH SOME ACCELERATION AS WELL. WINDS MAY ALSO INCREASE FOR A
FEW HOURS OVERNIGHT MONDAY INTO TUESDAY MORNING VIA A STRONGER LOW
LEVEL JET. OVERALL PERSISTENCE FORECAST WILL COVER THE SEAS...2-4
FEET.
LONG TERM /THURSDAY THROUGH FRIDAY/...
AS OF 300 AM MONDAY...PERSISTENCE FORECAST FOR THE MARINE
COMMUNITY THROUGH THE END OF THE WEEK. SOUTHWEST WINDS OF 10-15
KNOTS WITH SOME INCREASE TO WARRANT 15-20 KNOTS FOR THE OVERNIGHT
HOURS VIA LOW LEVEL JETTING. SEAS REMAIN REPRESENTATIVE OF THE
SUMMERTIME PATTERN WITH 2-4 FEET.
&&
.ILM WATCHES/WARNINGS/ADVISORIES...
SC...HEAT ADVISORY UNTIL 8 PM EDT THIS EVENING FOR SCZ017-023-024-
032-033-039-053>056.
NC...HEAT ADVISORY UNTIL 8 PM EDT THIS EVENING FOR NCZ087-096-099-
105>110.
MARINE...NONE.
&&
$$
NEAR TERM...RGZ
SHORT TERM...SHK
LONG TERM...SHK
AVIATION...MRR/MAC
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
1124 AM EDT MON JUN 22 2015
.SYNOPSIS...
HIGH HEAT AND HUMIDITY WILL CONTINUE THROUGH AT LEAST THE MIDDLE
OF THE WEEK...WITH ISOLATED SHOWERS AND THUNDERSTORMS DURING THE
AFTERNOONS AND EVENINGS. SLIGHTLY COOLER TEMPERATURES ALONG WITH A
BETTER CHANCE OF SHOWERS AND THUNDERSTORMS WILL DEVELOP THIS
WEEKEND.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 1030 AM MONDAY...HOT WEATHER CONTINUES WITH WELL ABOVE
NORMAL TEMPERATURES COMBINING WITH HIGH HUMIDITY TO CREATE
POTENTIALLY DANGEROUS HEAT INDICES VALUES TODAY. A HEAT ADVISORY
WILL REMAIN IN EFFECT FOR ALL COUNTIES FROM LATE THIS MORNING AND
INTO THE EVENING HOURS...WITH HEAT INDEX VALUES RANGING FROM 104F
TO 109F DURING THOSE TIMES. ACTUAL TEMPERATURES WILL RANGE FROM
THE LOWER 90S NEAR THE BEACHES TO AROUND 100 WELL INLAND.
HIGH PRESSURE OFFSHORE IN COMBINATION WITH A THERMAL TROUGH INLAND
WILL CONTINUE A LIGHT AND MOIST SOUTHWESTERLY FLOW THAT WILL KEEP
DEWPOINTS ELEVATED FROM THE UPPER 60S TO MID 70S. THE UPPER RIDGE
BEGINS TO RE-STRENGTHEN DURING THIS PERIOD...AND THIS WILL HELP TO
SUPPRESS WIDESPREAD CONVECTION DESPITE AN UNSTABLE ATMOSPHERE AND
STEEP LOW LEVEL LAPSE RATES. HOWEVER...WITH SUCH STRONG SURFACE
HEATING WE CAN EXPECT ISOLATED TO WIDELY SCATTERED CONVECTION
CONCENTRATED ALONG THE SEA BREEZE FRONT THIS AFTERNOON AND
EVENING. HRRR SHOWS VERY ISOLATED ACTIVITY ALONG SEA BREEZE THIS
AFTERNOON. THE STEERING FLOW IS VERY WEAK AND THEREFORE ANY
SHOWERS WILL POP UP AND DIE FAIRLY RAPIDLY POSSIBLY PUTTING DOWN A
QUICK DOWNPOUR. OVERALL EXPECTING PLENTY OF SUNSHINE AND
POTENTIALLY DANGEROUS HEAT.
&&
.SHORT TERM /TUESDAY THROUGH WEDNESDAY NIGHT/...
AS OF 300 AM MONDAY...THE MID LEVEL FLOW/PATTERN WILL FEATURE A SUBTLE
NORTHWEST FLOW WITH 500MB HEIGHTS REMAINING AROUND 593-594DM. THIS
WILL KEEP THE VERY WARM TEMPERATURES IN PLACE THROUGH THE PERIOD.
EXCESSIVE HEAT WARNINGS REMAIN A POSSIBILITY EACH DAY BUT MORE
LIKELY THE CONTINUATION OF THE HEAT ADVISORY WILL SUFFICE. EXPECT
HIGHS TO ECLIPSE TRIPLE DIGITS INLAND WITH UPPER 90S ALONG THE
COAST. SOUNDINGS DO SHOW A SLIGHTLY BETTER CHANCE FOR CONVECTION
WEDNESDAY BUT OVERALL COVERAGE WILL REMAIN LIMITED.
&&
.LONG TERM /THURSDAY THROUGH SUNDAY/...
AS OF 300 AM MONDAY...THE BIG STORY REMAINS THE PATTERN CHANGE EXPECTED TO
OCCUR IN THE SECOND HALF OF THE PERIOD AS MID LEVEL TROUGHING
DEVELOPS OVER THE TENNESSEE VALLEY TO SOME DEGREE. THIS WILL BRING A
PROLONGED PERIOD OF A GOOD CHANCE OF SHOWERS AND THUNDERSTORMS ALONG
WITH TEMPERATURES EXPECTED TO TREND TOWARD CLIMATOLOGY. THE HIGHEST
POPS CURRENTLY ARE FOR SATURDAY WITH HIGH CHANCE VALUES. EITHER SIDE
OF THIS POPS ARE IN THE CHANCE RANGE WITH MORE OF A DIURNAL NATURE.
TEMPERATURES REMAIN ON THE VERY WARM SIDE THURSDAY AND FRIDAY. WITH
THE ADDED CONVECTION AND LOWER HEIGHTS...READINGS SCALE BACK
SOMEWHAT FOR THE WEEKEND.
&&
.AVIATION /14Z MONDAY THROUGH FRIDAY/...
AS OF 12Z...TERMINALS ARE VFR THIS MORNING. TYPICAL SUMMER WEATHER
PATTERN WITH LIGHT SW-W WINDS...EXCEPT BECOMING S-SSW AT THE COASTAL
TERMINALS LATE MORNING/EARLY AFTERNOON AS THE SEA BREEZE DEVELOPS
AND MOVES INLAND. MOISTURE IS LACKING BUT GIVEN THE INSTABILITY
ISOLATED THUNDERSTORMS SHOULD DEVELOP ALONG THE SEA BREEZE BOUNDARY
AND ALONG THE PIEDMONT TROUGH INLAND. BEST TIME FRAME FOR VCTS AT
THE COASTAL TERMINALS WILL BE 17-21Z OR UNTIL THE SEA BREEZE
BOUNDARY MOVES FAR ENOUGH INLAND...AND INLAND TERMINALS 20-24Z.
CONVECTION DISSIPATES THIS EVENING WITH LIGHT SW WINDS CONTINUING
THROUGH THE NIGHT.
EXTENDED OUTLOOK...CHANCE OF SHOWERS/THUNDERSTORMS TUE-SAT WITH
MAINLY VFR.
&&
.MARINE...
NEAR TERM /THROUGH TONIGHT/...
AS OF 1030 AM MONDAY...LIGHT SOUTHWEST FLOW AROUND ATLANTIC HIGH
PRESSURE WILL CONTINUE THROUGH TONIGHT. WINDS WILL SPIKE UP
BECOMING GUSTY AS THEY BACK SLIGHTLY IN A SLIGHTLY TIGHTER
GRADIENT THIS AFTERNOON BETWEEN THERMAL TROUGH INLAND AND HIGH
OFF SHORE. OVERALL EXPECT SW WINDS 10 TO 15 KTS. SEAS UP AROUND 3
TO 4 FT IN A STRONGER SOUTHERLY PUSH YESTERDAY WILL SUBSIDE DOWN
TO 2 TO 3 FT BY TONIGHT. EXPECT CHOPPIER SEAS IN SEA BREEZE
THROUGH THIS AFTERNOON.
SHORT TERM /TUESDAY THROUGH WEDNESDAY NIGHT/...
AS OF 300 AM MONDAY...SOUTHWEST WINDS OF 10-15 KNOTS WILL PREVAIL
ACROSS THE COASTAL WATERS THROUGH THE PERIOD. THERE WILL BE SOME
BACKING OF THE WIND DIRECTION ALONG THE COAST DURING THE AFTERNOON
HOURS WITH SOME ACCELERATION AS WELL. WINDS MAY ALSO INCREASE FOR A
FEW HOURS OVERNIGHT MONDAY INTO TUESDAY MORNING VIA A STRONGER LOW
LEVEL JET. OVERALL PERSISTENCE FORECAST WILL COVER THE SEAS...2-4
FEET.
LONG TERM /THURSDAY THROUGH FRIDAY/...
AS OF 300 AM MONDAY...PERSISTENCE FORECAST FOR THE MARINE
COMMUNITY THROUGH THE END OF THE WEEK. SOUTHWEST WINDS OF 10-15
KNOTS WITH SOME INCREASE TO WARRANT 15-20 KNOTS FOR THE OVERNIGHT
HOURS VIA LOW LEVEL JETTING. SEAS REMAIN REPRESENTATIVE OF THE
SUMMERTIME PATTERN WITH 2-4 FEET.
&&
.ILM WATCHES/WARNINGS/ADVISORIES...
SC...HEAT ADVISORY UNTIL 8 PM EDT THIS EVENING FOR SCZ017-023-024-
032-033-039-053>056.
NC...HEAT ADVISORY UNTIL 8 PM EDT THIS EVENING FOR NCZ087-096-099-
105>110.
MARINE...NONE.
&&
$$
NEAR TERM...RGZ
SHORT TERM...SHK
LONG TERM...SHK
AVIATION...MRR
AREA FORECAST DISCUSSION
NWS NEWPORT/MOREHEAD CITY NC
957 AM EDT MON JUN 22 2015
.SYNOPSIS...
A WEAK FRONT WILL PASS THROUGH THE NORTHEAST CORNER OF THE STATE
TODAY. ANOTHER FRONT WILL MOVE IN ON WEDNESDAY AND BECOME
STATIONARY ACROSS THE REGION THROUGH SATURDAY. IT WILL THEN LIFT
NORTH AS A WARM FRONT SUNDAY.
&&
.NEAR TERM /TODAY/...
AS OF 955 AM MON...BERMUDA HIGH REMAINS IN PLACE WITH A VERY WARM
AND HUMID AIRMASS. NO SIG CHANGES NEEDED TO PREVIOUS FORECAST FOR
UPDATE. LOW LEVEL THICKNESS VALUES AND 850MB TEMPS 19-20C SUPPORT
HIGHS IN THE 90S TODAY...UPPER MID/UPPER 90S INLAND. HEAT INDEX
TEMPS IN THE ADVISORY RANGE AND WILL CONTINUE THE ADVISORY FOR ALL
BUT THE OUTER BANKS...FOR HEAT INDEX VALUES 105-109 THIS
AFTERNOON. WEAK FRONTAL BOUNDARY...CURRENTLY ANALYZED OVER SE
VA...WILL PASS THROUGH THE NORTHEAST PORTION OF THE STATE TODAY.
THAT AND THE SEABREEZE WILL BE ENOUGH TO CONTINUE SLIGHT CHANCE
POPS THIS AFTERNOON AND EARLY EVENING. HRRR AND NSSL WRF SHOW
ISOLATED TO WIDELY SCATTERED CONVECTION DEVELOPING THIS
AFTERNOON. AN ISOLATED STRONG THUNDERSTORM WITH GUSTY WINDS WILL
BE POSSIBLE.
&&
.SHORT TERM /TONIGHT/...
AS OF 3 AM MON...WEAK DYNAMICS FOR CONVECTION SO ANYTHING THAT
DEVELOPS WILL DISSIPATE QUICKLY THIS EVENING WITH THE LOSS OF
DAYTIME HEATING. WARM AND MUGGY OVERNIGHT WITH LOWS IN THE UPPER
70S TO LOWER 80S.
&&
.LONG TERM /TUESDAY THROUGH SUNDAY/...
AS OF 330 AM MONDAY...HEAT AND HUMIDITY WILL START THE WEEK BUT
BETTER CHANCES OF RAINFALL AND SLIGHTLY COOLER WEATHER RETURNS FOR
MID TO LATE WEEK.
TUESDAY/TUESDAY NIGHT...TUESDAY SHOULD BE THE HOTTEST DAY OF THE
WEEK AS RISING UPPER HEIGHTS WILL COMBINE WITH A MOIST SW FLOW TO
PUSH HIGH TEMPERATURES INTO THE UPPER 90S INLAND WITH LOWER 90S
COAST WITH HEAT INDICES OVER 105 DEGREES. RAIN CHANCES WILL BE
MINIMAL TUESDAY...MAINLY WITH THE SEA BREEZE OVER INLAND SOUTHERN
SECTIONS OF THE CWA.
WEDNESDAY/WEDNESDAY NIGHT...WEAK BACK DOOR FRONT DROPS INTO THE
AREA LATE WEDNESDAY NIGHT. CONVERGENCE AHEAD OF THE FRONT WILL
LEAD TO A CHANCE OF SHOWERS/THUNDERSTORMS DURING THE
AFTERNOON...GREATEST CHANCES OVER THE NORTHERN CWA. AS UPPER
HEIGHTS FALL AND SEVERAL MID-LEVEL SHORTWAVES CROSS THE AREA IN
THE NORTHWEST FLOW ALOFT...WILL CONTINUE THE RAIN CHANCES THROUGH
WEDNESDAY NIGHT. THE FRONT STALLS AND EVENTUALLY WASHES OUT BY
EARLY THURSDAY.
THURSDAY/THURSDAY NIGHT...WITH A CONTINUED MOIST SOUTHWEST FLOW
AND LOWERING MID-LEVEL HEIGHTS...WILL HAVE INCREASED CLOUD COVER
AND BETTER CHANCES OF SHOWERS/THUNDERSTORMS THURSDAY AND THURSDAY
NIGHT. HIGH TEMPERATURES WILL STILL REACH THE LOW/MID 90S...BUT
NIGHTTIME TEMPERATURES WILL BE COOLER WITH AREAS OF RAIN-COOLED
AIR.
FRIDAY THROUGH SUNDAY...AN UNSETTLED PATTERN CONTINUES FOR FRIDAY
THROUGH NEXT WEEKEND WITH THE COMBINATION OF FALLING UPPER LEVEL
HEIGHTS AND A MOIST SOUTHWEST FLOW WITH A WEAK FRONTAL BOUNDARY
STALLING NEAR THE REGION. WILL KEEP CHANCE POPS IN THE FORECAST
FOR SCATTERED SHOWERS/THUNDERSTORMS AT MOST ANYTIME THROUGH THE
PERIOD. THANKFULLY...TEMPERATURES WILL BE A BIT COOLER...WITH
HIGHS GENERALLY UPPER 80S TO LOWER 90S AND LOWS IN THE LOW/MID
70S.
&&
.AVIATION /14Z MONDAY THROUGH FRIDAY/...
SHORT TERM /THROUGH MON NIGHT/...
AS OF 7 AM MONDAY...EARLY MORNING PATCHY FOG WILL BURN OFF IN THE
NEXT HOUR OR SO. SURFACE FLOW FROM THE SOUTHWEST 10-15 KNOTS BY
DAY AND LESS THAN 10 KNOTS AT NIGHT. ISOLATED DIURNAL CONVECTION
POSSIBLE MAINLY FROM EARLY AFTERNOON THROUGH EARLY EVENING. MOSTLY
CLEAR OVERNIGHT BUT MOIST BOUNDARY LAYER MAY ALLOW PATCHY IFR/MVFR
FOG TO DEVELOP AGAIN.
LONG TERM /TUESDAY THROUGH FRIDAY/...
AS OF 345 AM MONDAY...GENERALLY VFR CONDITIONS ARE EXPECTED FOR
MOST OF THE EXTENDED PERIOD. SCATTERED SHOWERS/THUNDERSTORMS MAY
BRIEFLY REDUCE CONDITIONS TO MVFR. IN AREAS THAT DO RECEIVE
RAINFALL...PATCHES OF LATE NIGHT FOG AND STRATUS MAY ALSO BRIEFLY
REDUCE CONDITIONS TO MVFR AND PERHAPS TO IFR THROUGH THE PERIOD.
&&
.MARINE...
SHORT TERM /THROUGH TONIGHT/...
AS OF 955 AM MON...LATEST OBS SHOW VARIABLE WINDS ACROSS THE
WATERS AS WEAK BOUNDARY OVER SE VA CONTINUES TO SLOWLY MOVE
SOUTHWARD. N/NW WINDS 5-10KT ACROSS THE ALBEMARLE SOUND AND
NORTHERN WATERS...AND WSW/SW WINDS 5-15KT SOUTH...WITH SEAS 2-4FT.
BERMUDA HIGH REMAINS THE MAIN FEATURE. WIND DIRECTIONS WILL
CONTINUE TO BE TRICKY TODAY AS BOUNDARY SAGS SOUTH...LIGHTER
WINDS ACROSS THE NORTH AND SLIGHTLY STRONGER IN THE SOUTHERN
WATERS. BOUNDARY IS EXPECTED TO WASH OUT/LIFT BACK TO THE NORTH
TONIGHT WITH WINDS RETURNING S/SW ACROSS ALL WATERS BY LATE
TONIGHT...AS SEAS CONTINUE AT 2-4FT.
LONG TERM /TUESDAY THROUGH FRIDAY/...
AS OF 350 AM MONDAY...SOUTHWEST WINDS WILL BECOME GUSTY DURING THE
AFTERNOON AND EVENING ON TUESDAY WITH THE GRADIENT BETWEEN INLAND
TROUGH AND HIGH PRESSURE OFFSHORE. WILL SEE SOME 15 TO 20 KNOT
WINDS WITH SEAS BUILDING TO 3 TO 5 FEET...ESPECIALLY OVER THE
CENTRAL WATERS. A WEAK BACK DOOR COLD FRONT WILL DROP INTO THE
WATERS WEDNESDAY AND WEDNESDAY NIGHT BUT WILL QUICKLY WASH OUT
WITH A S/SW WIND FLOW RESUMING BY EARLY THURSDAY. SOUTHWEST
GRADIENT AGAIN INCREASES BEHIND SURFACE LOW MOVES ACROSS VIRGINIA
AND HIGH OFFSHORE THURSDAY NIGHT AND ESPECIALLY FRIDAY WITH THE
LATEST WAVE MODELS SHOWING SEAS BUILDING TO AS HIGH AS 6 TO 7 FEET
BY FRIDAY WITH SMALL CRAFT ADVISORIES LIKELY BY THIS TIME.
&&
.CLIMATE...
RECORD HIGH TEMPERATURES MONDAY: 6/22
LOCATION-----TEMP/YEAR--NOTES
NEW BERN 97/1994 (KEWN ASOS)
HATTERAS 92/1994 (KHSE ASOS)
GREENVILLE 102/1933 (COOP - NOT KPGV ASOS)
MOREHEAD CITY 94/1994 (COOP - NOT KMRH ASOS)
KINSTON 100/1952 (COOP - NOT KISO ASOS)
JACKSONVILLE 100/1981 (KNCA AWOS)
RECORD HIGH TEMPERATURES TUESDAY: 6/23
LOCATION-----TEMP/YEAR--NOTES
NEW BERN 98/1988 (KEWN ASOS)
HATTERAS 88/1996 (KHSE ASOS)
GREENVILLE 100/1933 (COOP - NOT KPGV ASOS)
MOREHEAD CITY 95/1988 (COOP - NOT KMRH ASOS)
KINSTON 102/1911 (COOP - NOT KISO ASOS)
JACKSONVILLE 99/2010 (KNCA AWOS)
&&
.MHX WATCHES/WARNINGS/ADVISORIES...
NC...HEAT ADVISORY UNTIL 8 PM EDT THIS EVENING FOR NCZ029-044>047-
079>081-090>095-098.
MARINE...NONE.
&&
$$
SYNOPSIS...HSA
NEAR TERM...CQD/HSA
SHORT TERM...HSA
LONG TERM...CTC
AVIATION...CTC/HSA
MARINE...CTC/CQD/HSA
CLIMATE...MHX
AREA FORECAST DISCUSSION
NWS BISMARCK ND
943 PM CDT TUE JUN 23 2015
.UPDATE...
ISSUED AT 937 PM CDT TUE JUN 23 2015
THE CHALLENGE FOR THE REMAINDER OF THE NIGHT IS THE COVERAGE AND
INTENSITY OF CONVECTION LATE TONIGHT ACROSS WESTERN AND CENTRAL
NORTH DAKOTA FROM THUNDERSTORM ACTIVITY THAT WILL PROPAGATE EAST
FROM CENTRAL AND EASTERN MONTANA. THE 01 UTC RAP DEPICTS MULTIPLE
IMPULSES EVIDENCED BY ONGOING CONVECTION ACROSS MONTANA
PROPAGATING INTO NORTH DAKOTA TONIGHT. 850 MB CAPE VALUES ARE IN
THE 500-800 J/KG RANGE WITH STRONG DEEP LAYER SHEAR WITH THE FAST
WESTERLIES ALOFT. THUS...SMALL HAIL APPEARS TO BE THE LIKELY
THREAT WITH SCATTERED CONVECTION SUSTAINED BY A STRENGTHENING LOW
LEVEL JET AND WARM AIR ADVECTION INTO NORTH DAKOTA.
UPDATE ISSUED AT 543 PM CDT TUE JUN 23 2015
THE 19-21 UTC HRRR ITERATIONS HAVE A GOOD HANDLE ON THE ONGOING
CONVECTION ACROSS WESTERN NORTH DAKOTA...AND WILL USE A BLEND OF
THEIR SOLUTIONS FOR SKY COVER AND POPS THROUGH THE EVENING AND
OVERNIGHT.
A MARGINAL THREAT FOR LARGE HAIL AND DAMAGING WINDS WILL CONTINUE
ACROSS SOUTHWEST AND POSSIBLY INTO SOUTH CENTRAL NORTH DAKOTA
THROUGH SUNSET. THE 22 UTC RAP ANALYSIS DEPICTS STRONG DEEP LAYER
SHEAR OF 40 KTS...WITH ML CAPE VALUES AROUND 1000-1500 J/KG...400
J/KG OF HAIL CAPE AND DOWNDRAFT CAPE AROUND 1000 J/KG.
OVERALL...DEEPER MOISTURE APPEARS TO BE A MITIGATING FACTOR FOR
GREATER STORM INTENSITY. MULTIPLE FUNNEL CLOUD REPORTS HAVE ALSO
BEEN RECEIVED ACROSS THE SOUTHWEST GIVEN THE AT TIMES SUPERCELLUR
NATURE OF THE STORMS. HOWEVER...LOW LEVEL KINEMATIC FIELDS ARE NOT
OVERLY SUPPORTIVE OF TORNADOES.
&&
.SHORT TERM...(THIS AFTERNOON THROUGH WEDNESDAY)
ISSUED AT 129 PM CDT TUE JUN 23 2015
FORECAST HIGHLIGHTS IN THE SHORT TERM PERIOD WILL BE CHANCES FOR
THUNDERSTORMS THROUGH THE PERIOD...SOME MARGINALLY SEVERE SOUTHWEST
THIS AFTERNOON/EVENING...AND ACROSS WESTERN AND CENTRAL NORTH DAKOTA
WEDNESDAY.
CURRENTLY...ACTIVE WEST-NORTHWEST FLOW ALOFT WITH A SFC TROUGH
STATIONARY ACROSS THE NORTHERN HIGH PLAINS OF MT/WY. UPPER LEVEL
DIVERGENCE IN THE EXIT REGION OF AN UPPER LEVEL JET COUPLED WITH
DIURNAL INSTABILITY WILL SEE THE CHANCE FOR SHOWERS AND
THUNDERSTORMS THIS AFTERNOON WEST AND NORTH...THEN SPREADING SLOWLY
SOUTHEAST TONIGHT. BEST CHANCE FOR STRONGER STORMS REMAINS ACROSS
THE WESTERN THIRD OF THE STATE...MORE SO THE SOUTHWEST WHERE MODELS
PORTRAY 800-1200 J/KG OF MUCAPE ALONG WITH 50KTS OF 0-6KM SHEAR.
LATEST HRRR ALONG WITH THE 00Z 4KM NSSL WRF INDICATE CONVECTIVE
DEVELOPMENT EARLY TO MID AFTERNOON FROM EASTERN MONTANA INTO
SOUTHWEST AND WEST CENTRAL NORTH DAKOTA. WILL MAINTAIN HIGH CHANCE
SCATTERED POPS FOR THIS AREA.
FOR WEDNESDAY...FLOW ALOFT AND UPPER DIVERGENCE REMAINS UNCHANGED
OVER THE NORTHERN PLAINS. SFC TROUGH ADVANCES EAST WED MORNING AND
AFTERNOON INTO THE CENTRAL DAKOTAS. DAYTIME INSTABILITY AND BULK
SHEAR INDICATE CHANCE FOR THUNDERSTORMS AREA WIDE...MARGINALLY
SEVERE OVER THE ENTIRE COUNTY WARNING AREA (ALL OF WEST AND CENTRAL
ND). WILL MAINTAIN POSSIBLE SEVERE WORDING IN THE HWO. DUE TO THE
UNCERTAINTY...OPTED TO NOT INCLUDE IN THE GRIDS AT THIS TIME.
.LONG TERM...(WEDNESDAY NIGHT THROUGH TUESDAY)
ISSUED AT 129 PM CDT TUE JUN 23 2015
CHANCES FOR SHOWERS AND THUNDERSTORMS ARE EXPECTED TO PERSIST INTO
WEDNESDAY NIGHT...AS AN UPPER LEVEL SHORTWAVE TROUGH CONTINUES ON AN
EASTWARD TRACK OUT OF THE STATE.
A TRANSITION FROM QUASI ZONAL FLOW ALOFT INTO NORTHWEST FLOW IS
EXPECTED THROUGH THURSDAY. THE CURRENT MODEL PACKAGE PROVIDES GOOD
AGREEMENT ON NORTH/NORTHWEST FLOW ALOFT REMAINING IN PLACE THROUGH
THE REST OF THE EXTENDED. SEVERAL EMBEDDED MID-LEVEL SHORTWAVES ARE
PROJECTED ACROSS THE AREA...RESULTING IN FREQUENT CHANCES FOR
ISOLATED/SCATTERED THUNDERSTORMS THOUGH PREDICTABILITY IS LOW.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z WEDNESDAY EVENING)
ISSUED AT 937 PM CDT TUE JUN 23 2015
AS OF 245 UTC...SCATTERED THUNDERSTORMS ACROSS SOUTHWEST NORTH
DAKOTA ARE NOT EXPECTED TO IMPACT THE TERMINALS. LATER TONIGHT
AND THROUGH THE DAY ON WEDNESDAY THUNDERSTORM COVERAGE WILL ONCE
AGAIN INCREASE. MVFR STRATUS IS POSSIBLE TONIGHT ACROSS WESTERN
AND CENTRAL NORTH DAKOTA. HOWEVER...ITS FORMATION REMAINS A BIT
UNCERTAIN.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...AYD
SHORT TERM...NH
LONG TERM...AC
AVIATION...AYD
AREA FORECAST DISCUSSION
NWS BISMARCK ND
1224 PM CDT MON JUN 22 2015
.UPDATE...
ISSUED AT 1224 PM CDT MON JUN 22 2015
LATEST VISIBLE SATELLITE IMAGERY SHOWS A LARGE CUMULUS FIELD
ACROSS WESTERN AND CENTRAL NORTH DAKOTA. SUBSIDENCE/DRY AIR ALOFT
BEHIND DEPARTING SHORTWAVE PER TIME/HEIGHT CROSS SECTIONS WILL
KEEP VERTICAL EXTENT/GROWTH OF THE CUMULUS LIMITED THIS AFTERNOON
WITH AN OVERALL DRY WEATHER REGIME. HIGH RESOLUTION MODELS ARE DRY
WITH THE EXCEPTION OF THE HRRR WHICH IS WAY OVERDONE WITH
PRECIPITATION AS OF 17Z. THUS HAVE TRIMMED THE SLIGHT CHC POPS
BACK TO THE TURTLE MOUNTAINS SOUTH TO THE JAMES RIVER VALLEY.
REST OF FORECAST REMAINS ON TRACK.
UPDATE ISSUED AT 939 AM CDT MON JUN 22 2015
MAIN UPDATE WAS TO SHRINK POPS EAST CENTRAL/JAMES RIVER VALLEY
THROUGH 18Z AS LOCAL RADAR SHOWS AN ABSENCE OF SHOWERS. LATEST
SUITE OF SATELLITE IMAGERY SHOWS THE 700MB-500MB TROUGH AXIS
EXITING CENTRAL NORTH DAKOTA. SUBSIDENCE BEHIND THIS SHORTWAVE
TROUGH WILL LIMIT DEPTH OF CUMULUS DEVELOPMENT AND POTENTIAL SHOWER
DEVELOPMENT THIS AFTERNOON. MINIMAL CAPE AND LIMITED CUMULUS
DEPTH/MOISTURE WILL RESULT IN WEAK PROSPECTS FOR SHOWERS. WILL
LOOK FURTHER INTO THE 12Z DATA. REST OF FORECAST REMAINS ON TRACK
FOR A DRY/BREEZY DAY.
UPDATE ISSUED AT 633 AM CDT MON JUN 22 2015
LATEST SATELLITE AND RADAR ANALYSIS INDICATES MOSTLY CLEAR SKIES
OVER WESTERN NORTH DAKOTA...WITH PATCHY MVFR-IFR CLOUDINESS FROM
MINOT TO JAMESTOWN IN THE WAKE OF THE OVERNIGHT CONVECTIVE SYSTEM.
MADE SOME MINOR ADJUSTMENTS TO POPS AND SKY COVER...AND REMOVED
MENTION OF THUNDER FOR THIS MORNING. OTHERWISE NO SIGNIFICANT
CHANGES TO THE GOING FORECAST.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 251 AM CDT MON JUN 22 2015
THUNDERSTORMS CONTINUE EARLY THIS MORNING ACROSS SOUTHEASTERN
NORTH DAKOTA. GENERALLY THESE STORMS ARE ON A DOWNWARD TREND.
HEAVY RAIN AND LIGHTNING WILL BE THE MAIN THREAT THROUGH THE
EARLY MORNING. BRIEF INTENSIFICATION MAY OCCUR...THEREFORE THE
SEVERE THUNDERSTORM WATCH REMAINS IN EFFECT. A COLD
FRONT...CURRENTLY SPREAD FROM NEAR BOWMAN UP THROUGH
BOTTINEAU...WILL CONTINUE TO PROPAGATE SOUTHEAST THIS MORNING.
ISOLATED SHOWERS ARE POSSIBLE ALONG THE FRONT. POST-FRONTAL
DIURNALLY DRIVEN CONVECTION IS POSSIBLE THIS AFTERNOON...MAINLY
EAST OF THE MISSOURI RIVER. THEREFORE...PUT IN A SLIGHT CHANCE FOR
ISOLATED THUNDERSTORMS THROUGH THE AFTERNOON.
TODAY WILL FEEL COOLER AS COLD AIR ADVECTING NORTHWEST WINDS
BRING IN COOL...AND SLIGHTLY DRIER AIR. HOWEVER...THIS WILL BE
SHORT-LIVED AS HIGH PRESSURE QUICKLY DEPARTS AND RETURN FLOW
KICKS IN TONIGHT.
.LONG TERM...(TUESDAY THROUGH SUNDAY)
ISSUED AT 251 AM CDT MON JUN 22 2015
SURFACE HIGH PRESSURE AND UPPER LEVEL RIDGING REMAIN OVER THE REGION
TO BEGIN THE LONG TERM PERIOD. COULD SEE AN ISOLATED SHOWER OR
THUNDERSTORM FAR WEST AND NORTH ON TUESDAY...BUT BY AND LARGE IT
LOOKS LIKE A DRY DAY.
MODELS ARE IN GENERAL AGREEMENT WITH A SHORTWAVE TROUGH THAT MOVES
THROUGH THE FORECAST AREA TUESDAY NIGHT AND WEDNESDAY BRINGING
SCATTERED SHOWERS AND THUNDERSTORMS.
WE BEGIN TO TRANSITION INTO A NORTHWEST FLOW TOWARD THE END OF THE
WORK WEEK AND INTO THE UPCOMING WEEKEND AS A STRONG UPPER LEVEL
RIDGE DEVELOPS OVER THE WESTERN U.S. ALTHOUGH THERE ARE MODEL
DIFFERENCES...WE REMAIN IN A NORTHWEST FLOW PATTERN. THUS WE WILL
CONTINUE TO SEE ALMOST DAILY CHANCES OF SHOWERS AND THUNDERSTORMS.
HOWEVER...EXPECT MUCH LESS AREAL COVERAGE...ESPECIALLY AS THE UPPER
LEVEL RIDGE BECOMES BETTER ESTABLISHED OVER THE WEEKEND AND INTO
EARLY NEXT WEEK.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON)
ISSUED AT 1224 PM CDT MON JUN 22 2015
SCT CUMULUS CLOUDS RANGING FROM 3500FT TO 5000FT WILL DISSIPATE
BY AROUND SUNSET...AS WILL THE NORTHWEST WINDS OF 15KT TO 25KT.
VFR CIGS/VSBYS NEXT 24HR.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...KS
SHORT TERM...AJ
LONG TERM...TWH
AVIATION...KS
AREA FORECAST DISCUSSION
NWS BISMARCK ND
1220 AM CDT MON JUN 22 2015
.UPDATE...
ISSUED AT 1215 AM CDT MON JUN 22 2015
MINOR UPDATE TO CAPTURE LATEST TRENDS. THE FIRST CLUSTER OF STORMS
HAS EXITED TO THE SOUTHEAST. ANOTHER LINE OF STORMS CONTINUES TO
PUSH EAST ALONG THE ND/SD BORDER. AT THIS TIME IT REMAINS BELOW
SEVERE LIMITS...HOWEVER GUSTY WINDS...LIGHTNING AND VERY HEAVY
RAIN IS LIKELY WITH THIS CLUSTER OF STORMS. IT SHOULD PUSH OUT OF
THE AREA BY AROUND 4 AM CDT.
UPDATE ISSUED AT 1053 PM CDT SUN JUN 21 2015
QUICK UPDATE TO CANCEL TORNADO WATCH AND REPLACE SOUTHERN COUNTIES
WITH SEVERE THUNDERSTORM WATCH NUMBER 327 UNTIL 5AM CDT. AN AREA
OF SEVERE STORMS ACROSS MCINTOSH AND DICKEY ARE EXPECTED TO
CONTINUE TO PUSH EAST OVER THE NEXT HOUR OR SO. ANOTHER COMPLEX OF
SEVERE STORMS ACROSS SOUTHWEST NORTH DAKOTA IS EXPECTED TO RIDE
ALONG THE ND/SD BORDER THROUGH THE OVERNIGHT AND INTO THE EARLY
MORNING HOURS.
UPDATE ISSUED AT 923 PM CDT SUN JUN 21 2015
UPDATE TO CANCEL MOUNTRAIL...WARD...RENVILLE.....
BOTTINEAU...MCHENRY...ROLETTE AND PIERCE COUNTIES FROM TORNADO
WATCH 324.
FOCUS IS TURNING BACK TO MONTANA AGAIN AS ANOTHER SUPERCELL JUST
EAST OF MILES CITY AS OF 225 UTC IS RAPIDLY PROPAGATING EAST.
HOWEVER...STILL UNCERTAIN IF THE STORM WILL START TURNING RIGHT
AND MISS FAR SOUTHWEST NORTH DAKOTA.
UPDATE ISSUED AT 647 PM CDT SUN JUN 21 2015
UPDATE TO CANCEL THE TORNADO WATCH FOR WILLIAMS...DIVIDE AND BURKE
COUNTIES.
OTHERWISE...AS OF 2345 UTC...ANVIL SHADING APPEARS TO HAVE COOLED
THE BOUNDARY LAYER JUST ENOUGH TO HOLD MOST CONVECTION ACROSS
WESTERN AND CENTRAL NORTH DAKOTA TO BELOW SEVERE LIMITS FOR NOW.
THE EXCEPTION BEING THE DOMINANT SUPERCELL ACROSS BOWMAN COUNTY
WHICH IS IN THE RELATIVELY UNDISTURBED ENVIRONMENT ON THE FAR
SOUTHERN END OF THE LINE OF CONVECTION ACROSS WESTERN NORTH
DAKOTA. THE 21-22 UTC HRRR RUNS STILL SUGGEST CONGEALING OF
CONVECTION....WHICH IS CONSISTENT WITH RECENT RADAR
TRENDS...ACROSS CENTRAL NORTH DAKOTA WITH TWO POTENTIAL
LINES...ONE ON THE NORTHERN FRINGE OF INSTABILITY ACROSS THE US
HIGHWAY 2 CORRIDOR AND A SECOND ACROSS SOUTHWEST AND SOUTH CENTRAL
NORTH DAKOTA. OVERALL...THE TORNADIC THREAT IS LIMITED SOMEWHAT BY
ANVIL SHADING AND BOUNDARY LAYER COOLING...WITH LARGE HAIL AND
DAMAGING WINDS THE PRIMARY THREATS.
&&
.SHORT TERM...(THIS EVENING THROUGH MONDAY)
ISSUED AT 211 PM CDT SUN JUN 21 2015
MAIN HIGHLIGHT IS THE SLIGHT RISK AND ENHANCED THUNDERSTORM
RISK CATEGORY ACROSS WESTERN AND CENTRAL NORTH DAKOTA THROUGH
SUNDAY NIGHT.
LATEST HIGH RESOLUTION MODELS CONTINUE TO PORTRAY TWO ROUNDS OF
SHOWERS/THUNDERSTORMS. LATEST REGIONAL/LOCAL RADAR SHOWS SCATTERED
SHOWERS/THUNDERSTORMS IN NORTHWEST NORTH DAKOTA...AND AN INCREASE
IN COVERAGE AND GROWTH EXPECTED IN THE NEXT FEW HOURS. HRRR REFLECTIVITY
FORECAST SHOWS SUPERCELLS DEVELOPING REST OF THIS AFTERNOON AND
MERGING INTO A COUPLE OF LINES/BOWING SEGMENTS 00Z THROUGH 05Z AS
THEY CROSS INTO THE JAMES RIVER VALLEY. ANOTHER ROUND OF THUNDERSTORMS
DEPICTED TO DEVELOP ALONG AND SOUTH OF INTERSTATE 94 BETWEEN 05Z
AND 12Z MONDAY. MORE THAN SUFFICIENT CAPE/SHEAR FOR A PLETHORA OF
SEVERE WEATHER THROUGH TONIGHT. CAPE NEARING 3000 J/KG ACROSS THE
SOUTHWEST WITH 65KT OF 0-6KM SHEAR. THIS WAS WELL ADVERTISED IN
PREVIOUS FORECASTS AND REMAINS WITH THIS DISCUSSION. LINGERING
SHOWERS/THUNDERSTORMS MONDAY MORNING CENTRAL THEN TAPERING OFF
BEFORE 18Z. DRY WEATHER MONDAY AFTERNOON.
.LONG TERM...(MONDAY NIGHT THROUGH SUNDAY)
ISSUED AT 211 PM CDT SUN JUN 21 2015
THE CURRENT ENSEMBLE AND DETERMINISTIC MODELS ARE PROJECTING QUASI
ZONAL FLOW ALOFT GIVING WAY TO NORTHWEST FLOW...AS AN UPPER LEVEL
TROUGH MOVES EASTWARD ACROSS THE STATE THROUGH WEDNESDAY...CREATING
WIDESPREAD CHANCES FOR SHOWERS AND THUNDERSTORMS.
THOUGH THE MODELS BEGIN TO WAVER LATER IN THE PERIOD...NORTHWEST
FLOW ALOFT IS EXPECTED TO REMAIN IN PLACE OVER THE NORTHERN PLAINS
THROUGH THE REST OF EXTENDED...AS A HIGH PRESSURE BUILDS OVER THE
CONUS SOUTHWEST.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT)
ISSUED AT 1215 AM CDT MON JUN 22 2015
GENERALLY VFR CONDITIONS ARE EXPECTED. MVFR CONDITIONS IN SHOWERS
AND THUNDERSTORMS ARE POSSIBLE AT KDIK/KBIS/KJMS EARLY THIS
MORNING. THE THREAT FOR SEVERE WEATHER WILL DIMINISH OVER THE NEXT
SEVERAL HOURS.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...AJ
SHORT TERM...KS
LONG TERM...AC
AVIATION...AJ
AREA FORECAST DISCUSSION
NWS CLEVELAND OH
718 AM EDT MON JUN 22 2015
.SYNOPSIS...
A STATIONARY FRONT ACROSS CENTRAL OHIO WILL LIFT BACK NORTH ACROSS
THE LOCAL AREA A WARM FRONT THIS AFTERNOON. A DEEPENING AREA OF LOW
PRESSURE WILL CROSS THE NORTHERN GREAT LAKES LATER TODAY AND
TONIGHT. A COLD FRONT FROM THIS LOW WILL MOVE SOUTHEAST ACROSS THE
AREA LATE TONIGHT AND EARLY TUESDAY. HIGH PRESSURE WILL SLIDE
ACROSS THE EASTERN GREAT LAKES WEDNESDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
WILL HAVE TO WATCH THE CONVECTION OVER IA/MN TO SEE IF IT HOLDS
TOGETHER. MOST OF THE GUIDANCE HAS THIS ACTIVITY MISSING THE AREA
BUT THE HRRR CONTINUES TO SHOW IT ARRIVING LATE IN THE AFTERNOON.
STILL THINK THE MAIN SHOW WILL BE TONIGHT. HAVE ADDED SEVERE
WORDING TO THE EVENING PORTION OF THE FORECAST. ADJUSTED CLOUD
COVER TO BETTER MATCH CURRENT CONDITIONS.
PREVIOUS...A COUPLE ROGUE SHOWERS REMAIN OVER EASTERN LAKE ERIE
BUT THE REMAINDER OF THE FORECAST AREA IS AGAIN DRY. JUST SOME
HIGH AND MID LEVEL CLOUDS RIGHT NOW. THE FRONT THAT MOVED THROUGH
SUNDAY HAS STALLED ACROSS CENTRAL OHIO AND IS EXPECTED TO COME
BACK NORTH ACROSS THE AREA AS A WARM FRONT LATER THIS AFTERNOON.
LOT`S OF UNCERTAINTY ON WHEN AND IF THIS FRONT WITH INITIATE
PRECIP THIS AFTERNOON. THE NAM APPEARS APPEARS TO BE THE OUTLIER
BY DEVELOPING A LOT OF PRECIP BY 00Z. THE OTHER GUIDANCE KEEPS THE
AREA MAINLY DRY AND THIS WILL BE THE SCENARIO FOLLOWED. HAVE
REMOVED THE PRECIP MENTION FROM THE FORECAST FOR TODAY EXCEPT IN
FAR NW OHIO. BETTER CHANCES FOR PRECIP WILL COME TONIGHT. EXPECT A
FAIR AMOUNT ON SUNSHINE TODAY AND THIS SHOULD PUSH TEMPS SEVERAL
DEGREES WARMER THAN THEY WERE ON SUNDAY.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH THURSDAY NIGHT/...
MAINLY ZONAL FLOW ALOFT IS EXPECTED DURING THE PERIOD SO NO
AIRMASS CHANGE WILL OCCUR THIS WEEK. LOT`S OF MODEL DIFFERENCES
TODAY CONCERNING TIMING OF PRECIP. ALL OF THE GUIDANCE APPEARS TO
BE HAVING TROUBLE WITH CONVECTIVE FEEDBACK. PRETTY CONFIDENT THAT
IT WILL RAIN TONIGHT...JUST NOT SURE WHEN. THE CHALLENGE TODAY IS
FIGURING OUT IF THE CONVECTION OVER MN RIGHT NOW WILL HOLD
TOGETHER AS IT DIVES SE ACROSS THE LAKES TODAY. THE GUIDANCE
DIFFERS ON THIS AND WILL GO WITH THE GFS/ECMWF SOLUTION OF HAVING
IT FALL APART BEFORE IT GETS HERE. AT THE SAME TIME THESE MODELS
DEVELOP ANOTHER LINE OF CONVECTION OVER THE WESTERN LAKES THIS
AFTERNOON. THIS PRECIP WILL HOLD TOGETHER AND SHOULD ARRIVE LATE
IN THE EVENING AND OVERNIGHT AND WILL BE JUST AHEAD OF THE SURFACE
COLD FRONT. THIS PRECIP WILL BE HELPED ALONG BY FAVORABLE DYNAMICS
ALOFT INCLUDING A TROUGH. TIME OF DAY WILL WORK IN FAVOR FOR THE
LOCAL AREA AS THE THREAT FOR SEVERE WEATHER WILL BE SOMEWHAT DIMINISHED
GIVEN THE TIME OF DAY. HAVE GONE AHEAD AND BUMPED PRECIP CHANCES
TO LIKELY MOST OF THE AREA FOR TONIGHT. BY MID TUESDAY
MORNING...THE FRONT AND MOST OF THE PRECIP SHOULD BE SOUTHEAST OF
THE AREA. THEN WILL TRY FOR A 36 TO 42 HOUR DRY PERIOD AS WEAK
HIGH PRESSURE PASSES TO THE NORTH. BOTH THE GFS AND ECMWF HAVE
SLOWED DOWN THE RETURN OF THE PRECIP TO THE AREA AND WEDNESDAY
SHOULD BE DRY. A WARM FRONT WILL WORK ITS WAY INTO THE AREA
WEDNESDAY NIGHT AND THAT SHOULD SIGNAL THE RETURN OF THUNDERSTORM
CHANCES. THE BOUNDARY WILL STALL AND KEEP THE PRECIP THREAT GOING
THROUGH THE END OF THE PERIOD. TEMPS WILL CONTINUE TO AVERAGE A
LITTLE ABOVE NORMAL FOR THE WEEK.
&&
.LONG TERM /FRIDAY THROUGH SUNDAY/...
AMPLIFICATION OF THE RIDGE IN THE WEST WILL RESULT IN
TROUGHING IN THE EAST BY WEEKS END. THIS WILL SEND A TREND TOWARD
COOLER TEMPERATURES INTO THE FORECAST AREA.
AS TROUGHINESS DEVELOPS IN THE UPPER LEVELS OVER THE FORECAST
AREA...TROUGH SLOWLY BECOMES NEUTRALLY TILTED AND EVENTUALLY CAUSES
A WAVE OF LOW PRESSURE TO DEVELOP OVER THE OHIO VALLEY AND MOVE
EAST. AT THIS TIME...IT APPEARS SOME MOISTURE AND UPPER LEVEL
SUPPORT COULD SLIP NORTH ACROSS THE AREA SATURDAY INTO SUNDAY AND
BRING A THREAT FOR SHOWERS AND THUNDERSTORMS TO THE AREA.
ALTHOUGH...PROBABILITIES WILL BE MINIMAL AND SO FAR THE TREND MAY BE
TO GRADUALLY TAPER THE SHOWER AND THUNDERSTORM THREAT OUT OF THE
FORECAST AS THE POTENTIAL EXISTS FOR KEEPING THE MOISTURE JUST SOUTH
OF THE FORECAST AREA. BUT...UNTIL THERE IS A BETTER HANDLE ON EXTENT
OF ACTIVITY...WILL KEEP THE MINIMAL CHANCE IN THE FORECAST.
TEMPERATURES WILL COOL DOWN A BIT INTO THE 70S FOR HIGHS EACH DAY AS
SOME WEAK COLD AIR ADVECTION SLIPS INTO THE FORECAST AREA. OVERNIGHT
LOWS WILL HOVER IN THE LOWER 60S.
&&
.AVIATION /12Z MONDAY THROUGH FRIDAY/...
BIG ISSUES TO DEAL WITH TODAY. WINDS ARE EXPECTED TO INCREASE
ALONG AND BEHIND THE WARM FRONT THIS AFTERNOON OUT OF THE
SOUTHWEST. A LINE OF SHOWERS AND THUNDERSTORMS COULD POSSIBLY
REACH TOLEDO AND FINDLAY BY LATE THIS AFTERNOON AND WEAKEN.
A THUNDERSTORM COMPLEX IS PROGGED TO MOVE INTO OUR AREA LATER
TONIGHT AND COULD BRING A ROUND OF STRONG THUNDERSTORMS TO THE
FORECAST AREA. TIMING WOULD PUT IT INTO THE TOLEDO AND FINDLAY
AREA AROUND MIDNIGHT OR SO BUT ACROSS THE REST OF THE AREA DURING
THE REST OF THE NIGHT.
OUTLOOK...NON VFR LIKELY EARLY TUESDAY AND AGAIN THURSDAY IN
SHOWERS AND THUNDERSTORMS.
&&
.MARINE...
LAKE IS GOING TO GET STIRRED UP ONCE AGAIN STARTING THIS
AFTERNOON INTO TUESDAY. WARM FRONT IS PROGGED TO MOVE NORTHEAST
ACROSS THE AREA THIS AFTERNOON FOLLOWED BY A COLD FRONT LATER
TONIGHT. AS STORM SYSTEM MOVES THROUGH THE AREA...SURFACE ISOBAR
GRADIENT WILL TIGHTEN ALLOWING WINDS TO INCREASE. WILL LIKELY NEED
TO HOIST A SMALL CRAFT ADVISORY LASTING INTO TUESDAY DUE TO THE
WINDS. WIND DO DIMINISH LATER IN THE DAY ON TUESDAY BECOMING LIGHT
AND VARIABLE TUESDAY NIGHT. THE LIGHT WIND FLOW CONTINUES THROUGH
MUCH OF WEDNESDAY WITH A BRIEF INCREASE WEDNESDAY NIGHT INTO
THURSDAY MORNING AS HIGH PRESSURE BUILDS INTO THE LAKES AREA. BUT
THEN WINDS INCREASE AGAIN ON FRIDAY AS LOW PRESSURE PASSES TO THE
SOUTH OF THE LAKE.
&&
.CLE WATCHES/WARNINGS/ADVISORIES...
OH...NONE.
PA...NONE.
MARINE...SMALL CRAFT ADVISORY FROM 2 AM TO 2 PM EDT TUESDAY FOR
LEZ147>149.
&&
$$
SYNOPSIS...KUBINA
NEAR TERM...KUBINA
SHORT TERM...KUBINA
LONG TERM...LOMBARDY
AVIATION...LOMBARDY
MARINE...LOMBARDY
AREA FORECAST DISCUSSION
NWS WILMINGTON OH
647 AM EDT MON JUN 22 2015
.SYNOPSIS...
A FRONTAL BOUNDARY LOCATED NEAR THE OHIO RIVER WILL LIFT
NORTHEAST AS A WARM FRONT TODAY...PROVIDING A CHANCE OF SHOWERS
AND THUNDERSTORMS. A COLD FRONT WILL BRING A BETTER CHANCE FOR
SHOWERS AND THUNDERSTORMS ON TUESDAY. HIGH PRESSURE WILL BUILD INTO
THE REGION FOR WEDNESDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
COMPLEX WEATHER SCENARIO IS SETTING UP FOR TODAY. BOUNDARY THAT
PUSHED THROUGH THE FA YESTERDAY...STRETCHES BACK TO THE WEST INTO
THE MID MS VALLEY. CONVECTION CONTINUES TO FIRE ALONG THIS
BOUNDARY AS IS EVIDENCED BY ANOTHER CLUSTER OF THUNDERSTORMS
WORKING OUT OF SRN IL INTO KY. FARTHER NW ON THE BOUNDARY IN IA
ANOTHER AREA HAS DEVELOPED. THIS ALL LEADS UP TO A LARGE MCS IN THE
NRN PLAINS. HRRR AND TO SOME EXTENT THE NAM ARE THE QUICKEST AND
FARTHEST SOUTH WITH THEIR HANDLING OF THE COMPLEX IN THE NRN
PLAINS. THEY TAKE IT INTO THE SRN PART OF THE LP OF MI BY 21Z.
OTHER MODELS ARE A LITTLE SLOWER. MEANWHILE...THE BOUNDARY IS FCST
TO LIFT NWD TODAY. SOME SCATTERED CONVECTION COULD DEVELOP ON IT.
WENT AHEAD LEANED TOWARDS THE HRRR/NAM SOLUTION AND BROUGHT SOME
HIGH CHANCE POPS INTO THE NRN COUNTIES LATE THIS AFTERNOON TO
COVER THE POSSIBILITY OF THE THUNDERSTORMS ON THE SRN EDGE OF THE
SYSTEM PASSING TO THE N. ELSEWHERE USED SLIGHT CHC POPS TO COVER
THE POSSIBILITY OF CONVECTION ALONG THE BOUNDARY.
HIGHS TODAY WILL BE SLIGHTLY ABOVE NORMAL RANGING FROM THE MID 80S
IN WEST CENTRAL OHIO TO AROUND 90 IN THE TRI-STATE.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH WEDNESDAY/...
TONIGHT...THERE SHOULD BE A LULL IN THE CONVECTION DURING THE
EVENING HOURS. AFTER MIDNIGHT...A CDFNT SWINGING THROUGH THE GREAT
LAKES WILL PUSH TOWARDS THE REGION. NRN PORTIONS OF THE FA WILL
HAVE A CHANCE OF SEEING THUNDERSTORMS LATE TONIGHT.
THE FRONT PUSH SOUTH THROUGH THE FA ON TUESDAY...BRINGING THE
CHANCE OF THUNDERSTORMS TO THE ENTIRE FA. AS SFC TEMPS WARM AHEAD
OF THE FRONT...MODERATE INSTABILITY SHOULD DEVELOP WITH CAPE FROM
2500 TO 3500 J/KG. FORECAST 0-6 KM SHEAR IS FROM 45 TO 50 KT. THUS
THE ONGOING THUNDERSTORMS SHOULD BE ABLE TO INTENSIFY AND SOME
STORMS COULD REACH SEVERE LIMITS. HAIL AND DAMAGING WIND GUSTS AS
WELL SHOULD BE POSSIBLE.
BY TUESDAY NIGHT THE FRONT AND CONVECTION SHOULD BE SOUTH OF THE
FA. WEAK HIGH PRESSURE BUILDS IN FOR WEDNESDAY.
LOWS WILL BE VERY WARM TONIGHT...STAYING IN THE LOWER TO MID 70S.
ON TUESDAY THE CONVECTION WILL HELP KEEP TEMPERATURES DOWN A
LITTLE. HIGHS WILL RANGE FORM THE LOWER 80S IN THE NW TO THE UPPER
80S IN THE NRN KY. SIMILAR HIGHS ARE EXPECTED FOR WEDNESDAY.
&&
.LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/...
MID LEVEL RIDGE ACROSS THE SOUTHERN US WITH ACTIVE BAND OF
WESTERLIES ACROSS THE NORTHERN TIER OF STATES AND GREAT LAKES TO
DOMINATE THE WEATHER THRU THE END OF THE WEEK. A SERIES OF
PERTURBATIONS TO COME THRU THE WESTERLY FLOW WITH E-W SURFACE
FRONTAL BOUNDARY OSCILLATING NORTH/SOUTH ACRS THE REGION.
FRONT LIFTS BACK NORTH LATER WED INTO THURSDAY AHEAD OF NEXT SFC
WAVE. ENHANCED CHANCE FOR PRECIP LOOKS TO BE ON THURSDAY WITH THE
PASSAGE OF THIS SFC WAVE.
MID LEVEL FLOW AMPLIFIES AND BECOMES NORTHWESTERLY AS THIS SFC WAVE
SHIFTS EAST. FRIDAY MAY END UP BEING DRY BUT FOR NOW HAVE DIMINISHED
POPS TO SLIGHT CHANCE WITH TIMING DIFFERENCES FROM VARIOUS SOLNS.
BETTER CHANCE FOR PCPN DEVELOPS SATURDAY WITH NEXT SFC WAVE PIVOTING
THRU GREAT LAKES. HAVE SPREAD CHANCE POPS BACK IN FRIDAY NIGHT INTO
SATURDAY. THIS CHANCE CONTINUE INTO NEXT SUNDAY WITH PASSAGE OF SFC
WAVE.
TEMPERATURES ARE EXPECTED TO BE AT OR ABOVE NORMAL WITH HIGHS
THRU THURSDAY RANGING FROM THE LOWER 80S FAR NORTH TO UPPER
80S/NEAR 90 SOUTH. TEMPERATURES SLIGHTLY COOLER NEXT
FRIDAY/SATURDAY AND SUNDAY WITH HIGHS FROM UPR 70S/NEAR 80 NORTH
TO LOWER 80S SOUTH.
&&
.AVIATION /12Z MONDAY THROUGH FRIDAY/...
A QUIET NEXT 24-30 HOURS IS IN STORE FOR THE REGIONS TAF SITES.
ANY MORNING FOG WILL LIFT WITHIN THE NEXT HOUR OR TWO. A WARM
FRONT WILL LIFT NORTHEAST THROUGH OHIO THIS MORNING AND WINDS WILL
BECOME SSW AT 10-12KTS WITH SCATTERED CU DEVELOPMENT. A PASSING
SHOWER IS POSSIBLE IN THE EARLY AFTERNOON...MORESO TOWARDS CENTRAL
OHIO. HAVE LEFT SHOWERS OUT OF THE FORECAST IN FAVOR OF WAITING TO
SEE IF THEY DO INITIATE AND IF SO...WHETHER THEY TRACK TOWARDS A
TAF SITE.
WINDS WILL SEE GUSTS TO 20KT THIS AFTERNOON...AND SKIES SHOULD
CLEAR IN THE EVENING. A COLD FRONT WILL TRACK SOUTHEAST THROUGH
THE REGION AND MAY SPARK SOME SHOWERS AROUND OR SHORTLY AFTER
DAYBREAK TUESDAY.
OUTLOOK...THUNDERSTORMS WILL BE POSSIBLE ON TUESDAY AFTERNOON.
THUNDERSTORMS WILL ALSO BE POSSIBLE AT TIMES FROM WEDNESDAY NIGHT
THROUGH FRIDAY.
&&
.ILN WATCHES/WARNINGS/ADVISORIES...
OH...NONE.
KY...NONE.
IN...NONE.
&&
$$
SYNOPSIS...CONIGLIO/SITES
NEAR TERM...SITES
SHORT TERM...SITES
LONG TERM...AR
AVIATION...FRANKS
AREA FORECAST DISCUSSION
NWS CLEVELAND OH
627 AM EDT MON JUN 22 2015
.SYNOPSIS...
A STATIONARY FRONT ACROSS CENTRAL OHIO WILL LIFT BACK NORTH ACROSS
THE LOCAL AREA A WARM FRONT THIS AFTERNOON. A DEEPENING AREA OF LOW
PRESSURE WILL CROSS THE NORTHERN GREAT LAKES LATER TODAY AND
TONIGHT. A COLD FRONT FROM THIS LOW WILL MOVE SOUTHEAST ACROSS THE
AREA LATE TONIGHT AND EARLY TUESDAY. HIGH PRESSURE WILL SLIDE
ACROSS THE EASTERN GREAT LAKES WEDNESDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
WILL HAVE TO WATCH THE CONVECTION OVER IA/MN TO SEE IF IT HOLDS
TOGETHER. MOST OF THE GUIDANCE HAS THIS ACTIVITY MISSING THE AREA
BUT THE HRRR CONTINUES TO SHOW IT ARRIVING LATE IN THE AFTERNOON.
STILL THINK THE MAIN SHOW WILL BE TONIGHT. HAVE ADDED SEVERE
WORDING TO THE EVENING PORTION OF THE FORECAST. ADJUSTED CLOUD
COVER TO BETTER MATCH CURRENT CONDITIONS.
PREVIOUS...A COUPLE ROGUE SHOWERS REMAIN OVER EASTERN LAKE ERIE
BUT THE REMAINDER OF THE FORECAST AREA IS AGAIN DRY. JUST SOME
HIGH AND MID LEVEL CLOUDS RIGHT NOW. THE FRONT THAT MOVED THROUGH
SUNDAY HAS STALLED ACROSS CENTRAL OHIO AND IS EXPECTED TO COME
BACK NORTH ACROSS THE AREA AS A WARM FRONT LATER THIS AFTERNOON.
LOT`S OF UNCERTAINTY ON WHEN AND IF THIS FRONT WITH INITIATE
PRECIP THIS AFTERNOON. THE NAM APPEARS APPEARS TO BE THE OUTLIER
BY DEVELOPING A LOT OF PRECIP BY 00Z. THE OTHER GUIDANCE KEEPS THE
AREA MAINLY DRY AND THIS WILL BE THE SCENARIO FOLLOWED. HAVE
REMOVED THE PRECIP MENTION FROM THE FORECAST FOR TODAY EXCEPT IN
FAR NW OHIO. BETTER CHANCES FOR PRECIP WILL COME TONIGHT. EXPECT A
FAIR AMOUNT ON SUNSHINE TODAY AND THIS SHOULD PUSH TEMPS SEVERAL
DEGREES WARMER THAN THEY WERE ON SUNDAY.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH THURSDAY NIGHT/...
MAINLY ZONAL FLOW ALOFT IS EXPECTED DURING THE PERIOD SO NO
AIRMASS CHANGE WILL OCCUR THIS WEEK. LOT`S OF MODEL DIFFERENCES
TODAY CONCERNING TIMING OF PRECIP. ALL OF THE GUIDANCE APPEARS TO
BE HAVING TROUBLE WITH CONVECTIVE FEEDBACK. PRETTY CONFIDENT THAT
IT WILL RAIN TONIGHT...JUST NOT SURE WHEN. THE CHALLENGE TODAY IS
FIGURING OUT IF THE CONVECTION OVER MN RIGHT NOW WILL HOLD
TOGETHER AS IT DIVES SE ACROSS THE LAKES TODAY. THE GUIDANCE
DIFFERS ON THIS AND WILL GO WITH THE GFS/ECMWF SOLUTION OF HAVING
IT FALL APART BEFORE IT GETS HERE. AT THE SAME TIME THESE MODELS
DEVELOP ANOTHER LINE OF CONVECTION OVER THE WESTERN LAKES THIS
AFTERNOON. THIS PRECIP WILL HOLD TOGETHER AND SHOULD ARRIVE LATE
IN THE EVENING AND OVERNIGHT AND WILL BE JUST AHEAD OF THE SURFACE
COLD FRONT. THIS PRECIP WILL BE HELPED ALONG BY FAVORABLE DYNAMICS
ALOFT INCLUDING A TROUGH. TIME OF DAY WILL WORK IN FAVOR FOR THE
LOCAL AREA AS THE THREAT FOR SEVERE WEATHER WILL BE SOMEWHAT DIMINISHED
GIVEN THE TIME OF DAY. HAVE GONE AHEAD AND BUMPED PRECIP CHANCES
TO LIKELY MOST OF THE AREA FOR TONIGHT. BY MID TUESDAY
MORNING...THE FRONT AND MOST OF THE PRECIP SHOULD BE SOUTHEAST OF
THE AREA. THEN WILL TRY FOR A 36 TO 42 HOUR DRY PERIOD AS WEAK
HIGH PRESSURE PASSES TO THE NORTH. BOTH THE GFS AND ECMWF HAVE
SLOWED DOWN THE RETURN OF THE PRECIP TO THE AREA AND WEDNESDAY
SHOULD BE DRY. A WARM FRONT WILL WORK ITS WAY INTO THE AREA
WEDNESDAY NIGHT AND THAT SHOULD SIGNAL THE RETURN OF THUNDERSTORM
CHANCES. THE BOUNDARY WILL STALL AND KEEP THE PRECIP THREAT GOING
THROUGH THE END OF THE PERIOD. TEMPS WILL CONTINUE TO AVERAGE A
LITTLE ABOVE NORMAL FOR THE WEEK.
&&
.LONG TERM /FRIDAY THROUGH SUNDAY/...
AMPLIFICATION OF THE RIDGE IN THE WEST WILL RESULT IN
TROUGHING IN THE EAST BY WEEKS END. THIS WILL SEND A TREND TOWARD
COOLER TEMPERATURES INTO THE FORECAST AREA.
AS TROUGHINESS DEVELOPS IN THE UPPER LEVELS OVER THE FORECAST
AREA...TROUGH SLOWLY BECOMES NEUTRALLY TILTED AND EVENTUALLY CAUSES
A WAVE OF LOW PRESSURE TO DEVELOP OVER THE OHIO VALLEY AND MOVE
EAST. AT THIS TIME...IT APPEARS SOME MOISTURE AND UPPER LEVEL
SUPPORT COULD SLIP NORTH ACROSS THE AREA SATURDAY INTO SUNDAY AND
BRING A THREAT FOR SHOWERS AND THUNDERSTORMS TO THE AREA.
ALTHOUGH...PROBABILITIES WILL BE MINIMAL AND SO FAR THE TREND MAY BE
TO GRADUALLY TAPER THE SHOWER AND THUNDERSTORM THREAT OUT OF THE
FORECAST AS THE POTENTIAL EXISTS FOR KEEPING THE MOISTURE JUST SOUTH
OF THE FORECAST AREA. BUT...UNTIL THERE IS A BETTER HANDLE ON EXTENT
OF ACTIVITY...WILL KEEP THE MINIMAL CHANCE IN THE FORECAST.
TEMPERATURES WILL COOL DOWN A BIT INTO THE 70S FOR HIGHS EACH DAY AS
SOME WEAK COLD AIR ADVECTION SLIPS INTO THE FORECAST AREA. OVERNIGHT
LOWS WILL HOVER IN THE LOWER 60S.
&&
.AVIATION /06Z MONDAY THROUGH FRIDAY/...
BIG ISSUES TO DEAL WITH TODAY. FIRST OF ALL WINDS ARE EXPECTED TO
INCREASE ALONG AND BEHIND THE WARM FRONT THIS AFTERNOON OUT OF THE
SOUTHWEST. SECOND...THUNDERSTORM COMPLEX IS PROGGED TO MOVE INTO
OUR AREA LATER TONIGHT AND COULD BRING A ROUND OF STRONG
THUNDERSTORMS TO THE FORECAST AREA. TIMING WOULD PUT IT INTO THE
TOLEDO AND FINDLAY AREA TOWARD THE END OF THE FORECAST PERIOD BUT
ACROSS THE REST OF THE AREA DURING THE REST OF THE NIGHT. IN THE
MEAN TIME...SOME MVFR FOG POSSIBLE THIS MORNING SHOULD BURN OFF
AFTER SUNRISE.
OUTLOOK...NON VFR WITH SHOWERS AND THUNDERSTORMS LATE TONIGHT.
NON VFR LIKELY EARLY TUESDAY AND AGAIN THURSDAY IN SHOWERS AND
THUNDERSTORMS.
&&
.MARINE...
LAKE IS GOING TO GET STIRRED UP ONCE AGAIN STARTING THIS
AFTERNOON INTO TUESDAY. WARM FRONT IS PROGGED TO MOVE NORTHEAST
ACROSS THE AREA THIS AFTERNOON FOLLOWED BY A COLD FRONT LATER
TONIGHT. AS STORM SYSTEM MOVES THROUGH THE AREA...SURFACE ISOBAR
GRADIENT WILL TIGHTEN ALLOWING WINDS TO INCREASE. WILL LIKELY NEED
TO HOIST A SMALL CRAFT ADVISORY LASTING INTO TUESDAY DUE TO THE
WINDS. WIND DO DIMINISH LATER IN THE DAY ON TUESDAY BECOMING LIGHT
AND VARIABLE TUESDAY NIGHT. THE LIGHT WIND FLOW CONTINUES THROUGH
MUCH OF WEDNESDAY WITH A BRIEF INCREASE WEDNESDAY NIGHT INTO
THURSDAY MORNING AS HIGH PRESSURE BUILDS INTO THE LAKES AREA. BUT
THEN WINDS INCREASE AGAIN ON FRIDAY AS LOW PRESSURE PASSES TO THE
SOUTH OF THE LAKE.
&&
.CLE WATCHES/WARNINGS/ADVISORIES...
OH...NONE.
PA...NONE.
MARINE...SMALL CRAFT ADVISORY FROM 2 AM TO 2 PM EDT TUESDAY FOR
LEZ147>149.
&&
$$
SYNOPSIS...KUBINA
NEAR TERM...KUBINA
SHORT TERM...KUBINA
LONG TERM...LOMBARDY
AVIATION...LOMBARDY
MARINE...LOMBARDY
AREA FORECAST DISCUSSION
NWS WILMINGTON OH
453 AM EDT MON JUN 22 2015
.SYNOPSIS...
A FRONTAL BOUNDARY LOCATED NEAR THE OHIO RIVER WILL LIFT
NORTHEAST AS A WARM FRONT TODAY...PROVIDING A CHANCE OF SHOWERS
AND THUNDERSTORMS. A COLD FRONT WILL BRING A BETTER CHANCE FOR
SHOWERS AND THUNDERSTORMS ON TUESDAY. HIGH PRESSURE WILL BUILD INTO
THE REGION FOR WEDNESDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
COMPLEX WEATHER SCENARIO IS SETTING UP FOR TODAY. BOUNDARY THAT
PUSHED THROUGH THE FA YESTERDAY...STRETCHES BACK TO THE WEST INTO
THE MID MS VALLEY. CONVECTION CONTINUES TO FIRE ALONG THIS
BOUNDARY AS IS EVIDENCED BY ANOTHER CLUSTER OF THUNDERSTORMS
WORKING OUT OF SRN IL INTO KY. FARTHER NW ON THE BOUNDARY IN IA
ANOTHER AREA HAS DEVELOPED. THIS ALL LEADS UP TO A LARGE MCS IN THE
NRN PLAINS. HRRR AND TO SOME EXTENT THE NAM ARE THE QUICKEST AND
FARTHEST SOUTH WITH THEIR HANDLING OF THE COMPLEX IN THE NRN
PLAINS. THEY TAKE IT INTO THE SRN PART OF THE LP OF MI BY 21Z.
OTHER MODELS ARE A LITTLE SLOWER. MEANWHILE...THE BOUNDARY IS FCST
TO LIFT NWD TODAY. SOME SCATTERED CONVECTION COULD DEVELOP ON IT.
WENT AHEAD LEANED TOWARDS THE HRRR/NAM SOLUTION AND BROUGHT SOME
HIGH CHANCE POPS INTO THE NRN COUNTIES LATE THIS AFTERNOON TO
COVER THE POSSIBILITY OF THE THUNDERSTORMS ON THE SRN EDGE OF THE
SYSTEM PASSING TO THE N. ELSEWHERE USED SLIGHT CHC POPS TO COVER
THE POSSIBILITY OF CONVECTION ALONG THE BOUNDARY.
HIGHS TODAY WILL BE SLIGHTLY ABOVE NORMAL RANGING FROM THE MID 80S
IN WEST CENTRAL OHIO TO AROUND 90 IN THE TRI-STATE.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH WEDNESDAY/...
TONIGHT...THERE SHOULD BE A LULL IN THE CONVECTION DURING THE
EVENING HOURS. AFTER MIDNIGHT...A CDFNT SWINGING THROUGH THE GREAT
LAKES WILL PUSH TOWARDS THE REGION. NRN PORTIONS OF THE FA WILL
HAVE A CHANCE OF SEEING THUNDERSTORMS LATE TONIGHT.
THE FRONT PUSH SOUTH THROUGH THE FA ON TUESDAY...BRINGING THE
CHANCE OF THUNDERSTORMS TO THE ENTIRE FA. AS SFC TEMPS WARM AHEAD
OF THE FRONT...MODERATE INSTABILITY SHOULD DEVELOP WITH CAPE FROM
2500 TO 3500 J/KG. FORECAST 0-6 KM SHEAR IS FROM 45 TO 50 KT. THUS
THE ONGOING THUNDERSTORMS SHOULD BE ABLE TO INTENSIFY AND SOME
STORMS COULD REACH SEVERE LIMITS. HAIL AND DAMAGING WIND GUSTS AS
WELL SHOULD BE POSSIBLE.
BY TUESDAY NIGHT THE FRONT AND CONVECTION SHOULD BE SOUTH OF THE
FA. WEAK HIGH PRESSURE BUILDS IN FOR WEDNESDAY.
LOWS WILL BE VERY WARM TONIGHT...STAYING IN THE LOWER TO MID 70S.
ON TUESDAY THE CONVECTION WILL HELP KEEP TEMPERATURES DOWN A
LITTLE. HIGHS WILL RANGE FORM THE LOWER 80S IN THE NW TO THE UPPER
80S IN THE NRN KY. SIMILAR HIGHS ARE EXPECTED FOR WEDNESDAY.
&&
.LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/...
MID LEVEL RIDGE ACROSS THE SOUTHERN US WITH ACTIVE BAND OF
WESTERLIES ACROSS THE NORTHERN TIER OF STATES AND GREAT LAKES TO
DOMINATE THE WEATHER THRU THE END OF THE WEEK. A SERIES OF
PERTURBATIONS TO COME THRU THE WESTERLY FLOW WITH E-W SURFACE
FRONTAL BOUNDARY OSCILLATING NORTH/SOUTH ACRS THE REGION.
FRONT LIFTS BACK NORTH LATER WED INTO THURSDAY AHEAD OF NEXT SFC
WAVE. ENHANCED CHANCE FOR PRECIP LOOKS TO BE ON THURSDAY WITH THE
PASSAGE OF THIS SFC WAVE.
MID LEVEL FLOW AMPLIFIES AND BECOMES NORTHWESTERLY AS THIS SFC WAVE
SHIFTS EAST. FRIDAY MAY END UP BEING DRY BUT FOR NOW HAVE DIMINISHED
POPS TO SLIGHT CHANCE WITH TIMING DIFFERENCES FROM VARIOUS SOLNS.
BETTER CHANCE FOR PCPN DEVELOPS SATURDAY WITH NEXT SFC WAVE PIVOTING
THRU GREAT LAKES. HAVE SPREAD CHANCE POPS BACK IN FRIDAY NIGHT INTO
SATURDAY. THIS CHANCE CONTINUE INTO NEXT SUNDAY WITH PASSAGE OF SFC
WAVE.
TEMPERATURES ARE EXPECTED TO BE AT OR ABOVE NORMAL WITH HIGHS
THRU THURSDAY RANGING FROM THE LOWER 80S FAR NORTH TO UPPER
80S/NEAR 90 SOUTH. TEMPERATURES SLIGHTLY COOLER NEXT
FRIDAY/SATURDAY AND SUNDAY WITH HIGHS FROM UPR 70S/NEAR 80 NORTH
TO LOWER 80S SOUTH.
&&
.AVIATION /08Z MONDAY THROUGH FRIDAY/...
A QUIET NEXT 24-30 HOURS IS IN STORE FOR THE REGIONS TAF SITES.
SOME MORNING FOG WILL OCCUR THROUGH DAYBREAK. A WARM FRONT WILL
LIFT NORTHEAST THROUGH OHIO DURING THE MORNING AND WINDS WILL
BECOME SSW AT 10-12KTS WITH SCATTERED CU DEVELOPMENT. A PASSING
SHOWER IS POSSIBLE IN THE EARLY AFTERNOON...MORESO TOWARDS CENTRAL
OHIO. HAVE LEFT SHOWERS OUT OF THE FORECAST IN FAVOR OF WAITING TO
SEE IF THEY DO INITIATE AND IF SO...WHETHER THEY TRACK TOWARDS A
TAF SITE.
WINDS WILL SEE GUSTS TO 20KT THIS AFTERNOON...AND SKIES SHOULD
CLEAR IN THE EVENING. A COLD FRONT WILL TRACK SOUTHEAST THROUGH
THE REGION AND MAY SPARK SOME SHOWERS AFTER DAYBREAK TUESDAY.
OUTLOOK...THUNDERSTORMS WILL BE POSSIBLE ON TUESDAY AFTERNOON.
THUNDERSTORMS WILL ALSO BE POSSIBLE AT TIMES FROM WEDNESDAY NIGHT
THROUGH FRIDAY.
&&
.ILN WATCHES/WARNINGS/ADVISORIES...
OH...NONE.
KY...NONE.
IN...NONE.
&&
$$
SYNOPSIS...CONIGLIO/SITES
NEAR TERM...SITES
SHORT TERM...SITES
LONG TERM...AR
AVIATION...FRANKS
AREA FORECAST DISCUSSION
NWS CHARLESTON WV
231 AM EDT MON JUN 22 2015
.SYNOPSIS...
A FRONT MEANDERING NORTH AND SOUTH ACROSS THE REGION WILL BRING
ON AND OFF ROUNDS OF SHOWERS AND THUNDERSTORMS THROUGH MUCH OF THE
WEEK. TEMPERATURES SHOULD BE COOLER FOR THE WEEKEND.
&&
.NEAR TERM /THROUGH TONIGHT/...
SENT A QUICK UPDATE TO INCREASE HOURLY TEMPERATURES AND LOWS FOR
TONIGHT PER LATEST SFC OBS IN THE MID TO UPPER 70S. ADJUSTED SKY
GRIDS USING IR SATELLITE IMAGES SHOWING AREAS OF CLEARING ACROSS
THE NORTH AND CENTRAL WV. UPPER CLOUDS FROM A DYING MCS ACROSS
CENTRAL KY WILL SPREAD EAST OVER PORTIONS OF SOUTHERN WV
OVERNIGHT. REMOVED ALL POPS OVERNIGHT PER RADAR AND LATEST HIGH
RESOLUTION MODELS SHOWING NO PCPN FOR THE REST OF THE NIGHT.
PREVIOUS DISCUSSION BELOW...
630 PM UPDATE...
MADE A FEW TWEAKS TO THE FORECAST FOR THIS
AFTERNOON/EVENING. REDUCED POPS ACROSS THE NORTH A BIT FROM
PREVIOUS FORECAST...AND LESS ACTIVITY THERE DUE TO DRIER
ATMOSPHERE. DID ELECT TO ADD IN A SLIGHT CHANCE TO CHANCE ON
MONDAY...WITH ACTIVITY STARTING IN THE MORNING...AS NEAR TERM
MODELS INDICATING POSSIBILITY FOR ACTIVITY IN CENTRAL INDIANA TO
MAKE ITS WAY/SURVIVE INTO OUR CWA BY MORNING. CONTINUED SLIGHT TO
CHANCE TOMORROW AS FRONTAL BOUNDARY IS PROGGED GRADUALLY LIFT BACK
NORTH ACROSS THE CWA.
PREVIOUS DISCUSSION FOLLOWS...
FAIRLY UNIFORM CU FIELD OVER THE CWA THIS AFTERNOON WITH MOIST BL
IN PLACE. REMAINING DEBRIS CLOUDS HAVE SHIFTED INTO SOUTHERN COAL
FIELDS AND CENTRAL VA. OTHERWISE...SWIFT MID LEVEL FLOW LEADING TO
A FEW GUSTY WIND REPORTS HERE AND THERE. LATEST RAP AND HRRR
MODELS BOTH SEEM TO ADVERTISE THAT THE BEST FOCUS FOR CONVECTIVE
INITIATION THIS AFTERNOON WILL BE ACROSS THE SOUTHERN COAL FIELDS
OF WV. MAIN AXIS OF INSTABILITY AND MOISTURE STRETCHES ACROSS
CENTRAL KY AND INTO SRN WV WHICH CORRELATES WELL WITH HIRES
MODELS...AND EXPECTED CONVECTIVE DEVELOPMENT. 88D RETURNS FROM
1820Z ARE JUST STARTING TO SHOW SIGNS OF DEVELOPMENT IN KY...AND
VA WV BORDERS. FOR TEMPS...MADE MINOR TWEAKS TO TEMPS MAX
TEMPS...LEANING A LITTLE CLOSER TO MAV NUMBERS OVER THE MET.
&&
.SHORT TERM /TUESDAY THROUGH THURSDAY/...
COLD FRONT MOVES SOUTHEAST ON TUESDAY. AS IS USUALLY THE CASE IN
THE SUMMER...TIMING THE FRONT SOUTH...AND HOW FAR SOUTH IT MAKES IT
BY WEDNESDAY MORNING IS DIFFICULT.
AHEAD OF THE FRONT...IT SHOULD GET QUITE WARM...OR EVEN HOT...WITH
AFTERNOON READINGS ACROSS THE LOWLANDS IN THE UPPER 80S TO LOWER
90S. COMBINATION OF THESE TEMPERATURES AND ABUNDANT LOW-LEVEL
MOISTURE WILL RESULT IN THE AIRMASS BECOME QUITE UNSTABLE.
SPC HAS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS THE NORTHERN
TWO-THIRDS OF OUR FORECAST AREA...WITH A MARGINAL RISK ACROSS THE
SOUTH.
CURRENT THINKING IS THAT THE FRONT WILL BECOME STATIONARY EITHER
ACROSS OUR EXTREME SOUTHERN COUNTIES...OR JUST TO THE SOUTH OF THESE
COUNTIES TUESDAY NIGHT.
FRONT SHOULD REMAIN NEARLY STATIONARY WEDNESDAY INTO WEDNESDAY NIGHT
AS SURFACE HIGH PRESSURE SLIDES EAST TO OUR SOUTH. EXPECT HIGHEST
PRECIP CHANCES FOR THIS PERIOD TO BE LOCATED ACROSS OUR SOUTHERN
COUNTIES.
THE FRONT SHOULD THEN BEGIN TO MOVE BACK NORTH AS WARM FRONT LATE
WEDNESDAY NIGHT INTO THURSDAY. EXPECT THUNDERSTORM CHANCES SHOULD
SPREAD NORTH DURING THE DAY.
&&
.LONG TERM /THURSDAY NIGHT THROUGH SUNDAY/...
WE CONTINUE TO RIDE THE RAIN TRAIN WITH THE FRONTAL ZONE
OSCILLATING IN OUR VICINITY. WITH THE 500 MB RIDGE OUT WEST...HAVE
AFTERNOON TEMPERATURES TRENDING TOWARD BELOW NORMAL BY THE
WEEKEND.
REMAIN HAVE THE FRONT LIFTING BACK NORTH WEDNESDAY NIGHT INTO THURSDAY.
SO WILL INCREASE POPS CENTRAL AND NORTHERN COUNTIES DURING THE DAY ON THURSDAY.
MOST SIGNIFICANT WAVE ACTION/500 MB TROF/ APPEARS TO BE SATURDAY INTO
SATURDAY...SO DESPITE BEING DAY 6/7 WILL INCLUDE SOME LIKELY POPS.
THOSE MAXIMUM TEMPERATURES SHOULD BE HELD DOWN TOO.
USE WPC MEDIUM RANGE GUIDANCE FOR MAJORITY OF TIME FRAME.
&&
.AVIATION /07Z MONDAY THROUGH FRIDAY/...
AREAS OF CLEARING ARE EVIDENT ON SATELLITE IMAGES ACROSS MOST
SITES. HOWEVER...HIGH LEVEL DEBRIS CLOUDS FROM A DYING MCS OVER
CENTRAL KY WILL MOVE EAST INTO PORTIONS OF SOUTHEAST OH AND WV
OVERNIGHT. THE NORTHERN SECTIONS COULD SEE MORE CLEARING THROUGH
AT LEAST 09Z. THIS COULD ALLOW FOR RADIATIONAL COOLING AND PATCHY
FOG DEVELOPMENT AT EKN AND BKW DURING THE PREDAWN HOURS. IT WILL
TAKE SOME TIME TO STILL WARM TEMPERATURES TO REACH THEIR DEWPOINTS
OVERNIGHT. THEREFORE...EXPECT MOSTLY VFR CONDITIONS WITH
OCCASIONAL MVFR CEILINGS OVER PKB AND CRW...BUT TEMPORARILY IFR
CONDITIONS AT EKN AND BKW.
CONDITIONS WILL IMPROVE QUICKLY BY 12Z AREAWIDE WITH SOME HIGH
LEVEL CLOUDS.
A WEAK DISTURBANCE EARLY MONDAY MORNING COULD CREATE ISOLD
SHOWERS OR EVEN AN ISOLD THUNDERSTORM...12Z- 20Z TIME
PERIOD...CREATING BRIEF MVFR CONDITIONS AND GUSTY WINDS...MAINLY
ACROSS THE SOUTHERN HALF OF THE CWA.
OTHERWISE...EXPECTING MAINLY VFR CONDITIONS WITH LIGHT SURFACE
WINDS.
FORECAST CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 06Z MONDAY...
FORECAST CONFIDENCE: LOW TO MEDIUM.
ALTERNATE SCENARIOS: DEVELOPMENT OF MVFR/IFR FOG TONIGHT IN
QUESTION. DEVELOPMENT OF ISOLD CONVECTION ON MONDAY MAY DIFFER
FROM FORECAST.
.AFTER 06Z MONDAY... IFR POSSIBLE TUESDAY IN SHOWERS AND
THUNDERSTORMS.
&&
.RLX WATCHES/WARNINGS/ADVISORIES...
WV...NONE.
OH...NONE.
KY...NONE.
VA...NONE.
&&
$$
SYNOPSIS...JSH/ARJ
NEAR TERM...KMC/ARJ/SL
SHORT TERM...JSH
LONG TERM...KTB
AVIATION...ARJ
AREA FORECAST DISCUSSION
NWS CHARLESTON WV
120 AM EDT MON JUN 22 2015
.SYNOPSIS...
A MEANDERING EAST TO WEST FRONT WILL MEANDER/OSCILLATE
NORTH AND SOUTH. ROUNDS OF CONVECTION. TEMPERATURES MAY TREND
LOWER TOWARD THE WEEKEND.
&&
.NEAR TERM /THROUGH TODAY/...
SENT A QUICK UPDATE TO INCREASE HOURLY TEMPERATURES AND LOWS FOR
TONIGHT PER LATEST SFC OBS IN THE MID TO UPPER 70S. ADJUSTED SKY
GRIDS USING IR SATELLITE IMAGES SHOWING AREAS OF CLEARING ACROSS
THE NORTH AND CENTRAL WV. UPPER CLOUDS FROM A DYING MCS ACROSS
CENTRAL KY WILL SPREAD EAST OVER PORTIONS OF SOUTHERN WV
OVERNIGHT. REMOVED ALL POPS OVERNIGHT PER RADAR AND LATEST HIGH
RESOLUTION MODELS SHOWING NO PCPN FOR THE REST OF THE NIGHT.
PREVIOUS DISCUSSION BELOW...
630 PM UPDATE...
MADE A FEW TWEAKS TO THE FORECAST FOR THIS
AFTERNOON/EVENING. REDUCED POPS ACROSS THE NORTH A BIT FROM
PREVIOUS FORECAST...AND LESS ACTIVITY THERE DUE TO DRIER
ATMOSPHERE. DID ELECT TO ADD IN A SLIGHT CHANCE TO CHANCE ON
MONDAY...WITH ACTIVITY STARTING IN THE MORNING...AS NEAR TERM
MODELS INDICATING POSSIBILITY FOR ACTIVITY IN CENTRAL INDIANA TO
MAKE ITS WAY/SURVIVE INTO OUR CWA BY MORNING. CONTINUED SLIGHT TO
CHANCE TOMORROW AS FRONTAL BOUNDARY IS PROGGED GRADUALLY LIFT BACK
NORTH ACROSS THE CWA.
PREVIOUS DISCUSSION FOLLOWS...
FAIRLY UNIFORM CU FIELD OVER THE CWA THIS AFTERNOON WITH MOIST BL
IN PLACE. REMAINING DEBRIS CLOUDS HAVE SHIFTED INTO SOUTHERN COAL
FIELDS AND CENTRAL VA. OTHERWISE...SWIFT MID LEVEL FLOW LEADING TO
A FEW GUSTY WIND REPORTS HERE AND THERE. LATEST RAP AND HRRR
MODELS BOTH SEEM TO ADVERTISE THAT THE BEST FOCUS FOR CONVECTIVE
INITIATION THIS AFTERNOON WILL BE ACROSS THE SOUTHERN COAL FIELDS
OF WV. MAIN AXIS OF INSTABILITY AND MOISTURE STRETCHES ACROSS
CENTRAL KY AND INTO SRN WV WHICH CORRELATES WELL WITH HIRES
MODELS...AND EXPECTED CONVECTIVE DEVELOPMENT. 88D RETURNS FROM
1820Z ARE JUST STARTING TO SHOW SIGNS OF DEVELOPMENT IN KY...AND
VA WV BORDERS. FOR TEMPS...MADE MINOR TWEAKS TO TEMPS MAX
TEMPS...LEANING A LITTLE CLOSER TO MAV NUMBERS OVER THE MET.
&&
.SHORT TERM /TONIGHT THROUGH WEDNESDAY NIGHT/...
FIGURING THE BOUNDARY LAYER WINDS WILL INCREASE MONDAY NIGHT...WILL
GO WITH A WARMER NIGHT IN THE OHIO VALLEY COUNTIES. 925 MB WINDS
WINDS ON NAM ABOUT 30 TO 35 KNOTS VCNTY PKB.
AS IS USUALLY THE CASE IN THE SUMMER...TIMING THE FRONT SOUTH...AND
HOW FAR SOUTH IT MAKES IT BY WEDNESDAY MORNING IS DIFFICULT. WILL
NOT GO WITH THE FASTER 12Z GFS AT THIS TIME...BUT STILL PLAY UP
FAVORABLE TIMING FOR AFTERNOON CONVECTION. FIGURING 2500 CAPE COULD
DEVELOP...WITH SOME SEVERE CELLS POSSIBLE.
HAVE POPS LOWERING NORTH TO SOUTH...OVERNIGHT TUESDAY NIGHT...AS
FRONT SINKS SOUTH.
NOT CONFIDENT AT THIS TIME...THAT THE FRONTAL ZONE WILL CLEAR
SOUTHERN COUNTIES...SO LEFT SOME 20/30 POPS EVEN DURING THE
PREDAWN/DAWN TIME FRAME FOR WEDNESDAY. WILL TRY TO KEEP NORTHERN
COUNTIES DRY A BIT LONGER ON WEDNESDAY. HAVE THE FRONT LIFTING BACK
NORTH WEDNESDAY NIGHT INTO THURSDAY.
&&
.LONG TERM /THURSDAY THROUGH SUNDAY/...
WE CONTINUE TO RIDE THE RAIN TRAIN WITH THE FRONTAL ZONE OSCILLATING IN OUR
VICINITY. WITH THE 500 MB RIDGE OUT WEST...HAVE AFTERNOON TEMPERATURES
TRENDING TOWARD BELOW NORMAL BY THE WEEKEND.
REMAIN HAVE THE FRONT LIFTING BACK NORTH WEDNESDAY NIGHT INTO THURSDAY.
SO WILL INCREASE POPS CENTRAL AND NORTHERN COUNTIES DURING THE DAY ON THURSDAY.
MOST SIGNIFICANT WAVE ACTION/500 MB TROF/ APPEARS TO BE SATURDAY INTO
SATURDAY...SO DESPITE BEING DAY 6/7 WILL INCLUDE SOME LIKELY POPS.
THOSE MAXIMUM TEMPERATURES SHOULD BE HELD DOWN TOO.
USE WPC MEDIUM RANGE GUIDANCE FOR MAJORITY OF TIME FRAME.
&&
.AVIATION /05Z MONDAY THROUGH FRIDAY/...
AREAS OF CLEARING ARE EVIDENT ON SATELLITE IMAGES ACROSS MOST
SITES. HOWEVER...HIGH LEVEL DEBRI CLOUDS FROM A DYING MCS OVER
CENTRAL KY WILL MOVE EAST INTO PORTIONS OF SOUTHEAST OH AND WV
OVERNIGHT. THE NORTHERN SECTIONS COULD SEE MORE CLEARING THROUGH
AT LEAST 09Z. THIS COULD ALLOW FOR RADIATIONAL COOLING AND PATCHY
FOG DEVELOPMENT AT EKN AND BKW DURING THE PREDAWN HOURS. IT WILL
TAKE SOME TIME TO STILL WARM TEMPERATURES TO REACH THEIR DEWPOINTS
OVERNIGHT. THEREFORE...EXPECT MOSTLY VFR CONDITIONS WITH
OCCASIONAL MVFR CEILINGS OVER PKB AND CRW...BUT TEMPORARILY IFR
CONDITIONS AT EKN AND BKW.
CONDITIONS WILL IMPROVE QUICKLY BY 12Z AREAWIDE WITH SOME HIGH
LEVEL CLOUDS.
A WEAK DISTURBANCE EARLY MONDAY MORNING COULD CREATE ISOLD
SHOWERS OR EVEN AN ISOLD THUNDERSTORM...12Z- 20Z TIME
PERIOD...CREATING BRIEF MVFR CONDITIONS AND GUSTY WINDS...MAINLY
ACROSS THE SOUTHERN HALF OF THE CWA.
OTHERWISE...EXPECTING MAINLY VFR CONDITIONS WITH LIGHT SURFACE
WINDS.
FORECAST CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 06Z MONDAY...
FORECAST CONFIDENCE: LOW TO MEDIUM.
ALTERNATE SCENARIOS: DEVELOPMENT OF MVFR/IFR FOG TONIGHT IN
QUESTION. DEVELOPMENT OF ISOLD CONVECTION ON MONDAY MAY DIFFER
FROM FORECAST.
.AFTER 06Z MONDAY... IFR POSSIBLE TUESDAY IN SHOWERS AND
THUNDERSTORMS.
&&
.RLX WATCHES/WARNINGS/ADVISORIES...
WV...NONE.
OH...NONE.
KY...NONE.
VA...NONE.
&&
$$
SYNOPSIS...JSH/ARJ
NEAR TERM...KMC/ARJ/SL
SHORT TERM...JSH/KTB
LONG TERM...KTB
AVIATION...ARJ
AREA FORECAST DISCUSSION
NWS GREENVILLE-SPARTANBURG SC
439 PM EDT MON JUN 22 2015
.SYNOPSIS...
ONG HIGH PRESSURE WILL PERSIST ACROSS THE REGION THROUGH THE
MIDDLE OF THE WEEK MAINTAINING WELL ABOVE NORMAL TEMPERATURES. A
BROAD UPPER LEVEL TROF WILL MOVE OVER THE REGION OVER THE WEEKEND
RETURNING TEMPERATURES TO SEASONAL LEVELS BY SUNDAY AND INCREASING
CHANCES FOR WIDESPREAD SHOWERS AND THUNDERSTORMS.
&&
.NEAR TERM /THROUGH TUESDAY/...
AS OF 430 PM EDT...SOME STRONG THUNDERSTORMS HAVE DEVELOPED OVER
HIGHER TERRAIN AREAS OF WESTERN NORTH CAROLINA AND ADJACENT AREAS TO
THE EAST. HRRR GUIDANCE HAS ACTIVITY CONTINUING BUT MOVING OFF OF
THE MOUNTAINS INTO SOUTH CAROLINA AND DECREASING AFTER 0Z.
ADJUSTED POP AND WEATHER FOR LATEST RADAR AND CAM TRENDS. ALSO
ADJUSTED TEMPERATURES TO REDUCE TEMPERATURES IN RAIN-AFFECTED
AREAS.
AS OF 230 PM EDT...EXPECT THE GRADUAL EXPANSION OF CVRG ACRS THE
MTNS TO CONTINUE THROUGH LATE AFTERNOON WITH THE RISK OF ISOLATED
ACTIVITY IN THE PIEDMONT. DIURNALLY DRIVEN DEEP CONVECTION WILL WANE
WITH LOSS OF HTG THIS EVENING FOLLOWED BY A FAIR OVERNIGHT PERIOD.
THE PATTERN LOOKS TO BE NOMINALLY LESS SUPPRESSIVE ON TUESDAY WITH
SLIGHTLY BETTER LLVL MOISTURE AND MEAN FLOW. FOR NOW...WILL PLAN
ON RAMPING UP TO SCATTERED DIURNAL MTN CVRG AND ISOLATED ELSEWHERE.
TEMPERATURES WILL BE NEAR PERSISTENCE...PEAKING NEAR RECORD LEVELS
AGAIN TOMORROW. SFC DWPTS SHOULD BE ABLE TO MIX LOWER INTO/THRU THE
60S...KEEPING PIEDMONT HEAT INDEX VALUES BELOW ADVISORY THRESHOLD.
&&
.SHORT TERM /TUESDAY NIGHT THROUGH THURSDAY/...
AS OF 205 PM MONDAY...A COLD FRONT TRAILING FROM A LOW IN EASTERN
CANADA WILL BE LOSING STEAM AS IT GRADUALLY PUSHES TOWARD THE
WESTERN CAROLINAS AND NE GA. THE 12Z NAM/GFS ARE SIMILAR IN ALLOWING
WHAT IS LEFT OF THE FRONT TO DROP INTO THE LEE TROUGH EARLY WED
EXTENDING FROM UPSTATE SC...SW INTO NE GA. THE WEAK BOUNDARY IS
FORECAST TO REMAIN QUASI-STATIONARY ACROSS THE AREA INTO WED NIGHT
BEFORE MOVING NE AS A WARM FRONT ON THU AS ANOTHER LOW MOVES INTO
THE LOWER GREAT LAKES. ALOFT THE UPPER HIGH OVER THE SOUTHERN PLAINS
IS FORECAST TO NOSE EASTWARD INTO THE SOUTHERN APPALACHIANS THROUGH
THU WHICH WILL KEEP THICKNESSES HIGH WHICH SUPPORT A CONTINUATION OF
THE HOT TEMPS.
IN REGARD TO SENSIBLE WEATHER...ASSOCIATED CONVECTION WITH THE
FRONTAL BOUNDARY IS FORECAST TO MAKE A RUN AT THE MOUNTAINS TUE
EVENING...BUT AS IS USUALLY THE CASE THE THUNDERSTORM ACTIVITY IS
FORECAST TO DIMINISH AS IT TRIES TO TRAVERSE THE MOUNTAINS IN A
DIMINISHING CAPE ENVIRONMENT.
ON WED...MODEL RESPONSE FOR CONVECTIVE DEVLOPMENT IS RATHER MUTED
OUTSIDE THE MOUNTAINS AS PROFILES EXHIBIT SOME DRYING AND QUITE A
BIT OF CIN TO OVERCOME. LOOKS LIKE ISOLATED STORMS AT BEST THERE.
THE MOUNTAINS ARE A DIFFERENT STORY WITH SBCAPES FORECAST TO EXCEED
2000J WITH LESS CIN TO OVERCOME. PLUS SOME UPSTREAM CONVECTION MAY
MAKE A RUN AT THE MOUNTAINS. HENCE...WILL HAVE SOLID SCT TYPE POPS
ALL ACROSS THE HIGH TERRAIN. MOUNTAIN STORMS MAY SLIP INTO THE
ADJACENT FOOTHILLS AND EVEN THE PIEDMONT WED EVENING...SO WILL HAVE
POPS INCREASING THERE WED EVENING. GFS LOOKS OVERDONE WITH THE
AMOUNT OF CONVECTION OUTSIDE THE MOUNTAINS WED NIGHT...SO WILL TREND
FORECAST TOWARD NAM/SREF WHICH ARE CONSIDERABLY DRYER.
ON THU...A SIMILAR SCENARIO IS EXPECTED TO WED EVEN WITH THE WEAK
BOUNDARY MOVING OUT OF THE AREA. FORECAST SOUNDINGS AGAIN EXHIBIT
CONSIDERABLE CAPE...BUT PROFILES AGAIN SHOW ENOUGH CIN OUTSIDE THE
MOUNTAINS TO LIMIT CONVECTIVE INITIATION. WILL AGAIN FEATURE SCT
TYPE POPS ACROSS THE MOUNTAINS THU AFTERNOON IN STRONG DIFFERENTIAL
HEATING ENVIORNMENT.
TEMPS WILL REMAIN HOT AND WELL ABOVE CLIMO EACH DAY BUT BELOW RECORD
LEVELS.
&&
.LONG TERM /THURSDAY NIGHT THROUGH MONDAY/...
AS OF 230 PM EDT MONDAY...THE MEDIUM RANGE FCST PICKS UP AT 00Z ON
FRIDAY WITH A LARGE SCALE PATTERN SHIFT IN PROGRESS. HEIGHTS
GRADUALLY LOWER THRU THE FIRST PART OF THE PERIOD OVER THE SOUTHEAST
WHILE UPPER RIDGING STEEPENS OVER THE WESTERN CONUS. BY SUNDAY...THE
UPPER PATTERN IS VERY AMPLIFIED WITH A FAIRLY DEEP UPPER TROF OVER
THE EASTERN CONUS AND VERY STEEP RIDGING OVER THE WEST. THIS PATTERN
APPEARS LIKELY TO HOLD WELL BEYOND DAY 7. AT THE SFC...THE BERMUDA
HIGH WILL PERSIST OVER THE REGION THRU THE PERIOD WITH NUMEROUS WEAK
LOWS BEING GENERATED TO OUR WEST AND PROPAGATING EASTWARD. ON
FRIDAY...THE MODELS CONTINUE TO GENERATE SOME DEGREE OF LEE TROFFING
DURING THE LATER PART OF THE DAY/NIGHT AS A GREAT LAKES LOW MOVES
WELL NORTHEAST OF THE CWFA. ON SAT...ANOTHER LOW TRIES TO SPIN UP IN
THE VICINITY OF THE FCST AREA OR JUST TO OUR NE AND THEN SLOWLY
PROPAGATE NE AND OFF THE NEW ENGLAND COAST. A BROAD AREA OF DEEPER
LYR MOISTURE ASSOCIATED WITH THE LOW WILL SPREAD OVER THE FCST AREA
BY EARLY SAT AND REMAIN OVER THE CWFA THRU ROUGHLY THE FIRST HALF OF
SUN BEFORE MOVING OFF THE CAROLINA COAST. WEAK HIGH PRESSURE BRIEFLY
SPREADS BACK OVER THE AREA IN THE LOWS WAKE FOR MONDAY. AS FOR THE
SENSIBLE FCST...DIURNAL CONVECTION IS POSSIBLE EACH DAY WITH CHANCES
GENERALLY HIGHER OVER THE MTS AND NC FOOTHILLS. CHANCES INCREASE FOR
SAT AND SUN WITH THE INCREASING DEEP LYR MOISTURE OVER THE REGION
AND BETTER UPPER LVL SUPPORT OVERHEAD. TEMPS START OUT ABOVE
CLIMATOLOGY AND GRADUALLY DECREASE THRU THE PERIOD WITH HIGH TEMPS
ENDING A FEW DEGREES BELOW NORMAL.
&&
.AVIATION /21Z MONDAY THROUGH SATURDAY/...
AT KCLT...HIGHER LVL BASED CU WILL BE SEEN UNTIL LOSS OF HTG THIS
EVENING...FOLLOWED BY FAIR CONDITIONS TONIGHT WITH NO RESTRICTIONS
EXPECTED. LIGHT SOUTHERLY WINDS WILL CONTINUE TO VEER SOME THROUGH
THE REST OF THE DAY.
ELSEWHERE...THERE IS THE ONGOING RISK OF DIURNALLY FIRED SCATTERED
TSTMS ACRS THE NC MTNS AND EVENTUALLY INTO THE FTHLS LATER TODAY BUT
CVRG IS EXPECTED TO BE SPARSE ENUF TO FORGO ANY MENTION IN THE
TERMINALS. GIVEN THE DRY LLVL AIRMASS...TUESDAY MORNING MVFR FOG
POSSIBILITIES SHOULD BE LIMITED TO THE NC MTN VALLEYS AND POSSIBLY
AWAY FROM THE KAVL TERMINAL.
OUTLOOK...ISOLD TO SCT DIURNAL TSTM CHANCES WILL CONTINUE THROUGH
THE WEEK IN THE WARM AIRMASS. PRECIPITATION CHANCES WILL INCREASE
LATE IN THE WEEK AS A FRONT APPROACHES FROM THE NW. MORNING
RESTRICTIONS DUE TO FOG AND/OR STRATUS ARE POSSIBLE...PARTICULARLY
WHERE HEAVY RAIN FELL THE PREVIOUS DAY...AND MOST LIKELY IN THE MTN
VALLEYS.
CONFIDENCE TABLE...
20-02Z 02-08Z 08-14Z 14-18Z
KCLT HIGH 100% HIGH 100% HIGH 100% HIGH 100%
KGSP HIGH 100% HIGH 100% HIGH 100% HIGH 100%
KAVL HIGH 100% HIGH 100% HIGH 100% HIGH 100%
KHKY HIGH 100% HIGH 100% HIGH 100% HIGH 100%
KGMU HIGH 100% HIGH 100% HIGH 100% HIGH 100%
KAND HIGH 100% HIGH 100% HIGH 100% HIGH 100%
THE PERCENTAGE REFLECTS THE NUMBER OF GUIDANCE MEMBERS AGREEING
WITH THE SCHEDULED TAF ISSUANCE FLIGHT RULE CATEGORY. COMPLETE HOURLY
EXPERIMENTAL AVIATION FORECAST CONSISTENCY TABLES AND ENSEMBLE FORECASTS
ARE AVAILABLE AT THE FOLLOWING LINK: (MUST BE LOWER CASE)
WWW.WEATHER.GOV/GSP/AVIATION_TABLES
&&
.CLIMATE...
RECORD MAXIMUM TEMPERATURES FOR THIS WEEK...WITH YEARS IN WHICH THE
VALUES WERE LAST REACHED.
MONDAY JUNE 22...
AVL 94 1964
CLT 98 1956
GSP 99 2006
TUESDAY JUNE 23...
AVL 93 1988
CLT 98 1988
GSP 99 1988
WEDNESDAY JUNE 24...
AVL 94 1952
CLT 102 1930
GSP 100 1952
THURSDAY JUNE 25...
AVL 96 1952
CLT 102 1914
GSP 101 1952
&&
.GSP WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
NC...NONE.
SC...NONE.
&&
$$
SYNOPSIS...JPT
NEAR TERM...CSH/WJM
SHORT TERM...LG
LONG TERM...JP/JPT
AVIATION...CSH
CLIMATE...
AREA FORECAST DISCUSSION
NWS GREENVILLE-SPARTANBURG SC
336 AM EDT MON JUN 22 2015
.SYNOPSIS...
STRONG HIGH PRESSURE WILL PERSIST ACROSS THE REGION THROUGH THE
MIDDLE OF THE WEEK AND MAINTAIN WELL ABOVE NORMAL TEMPERATURES. A
LARGE UPPER LEVEL TROF WILL PUSH INTO THE REGION OVER THE WEEKEND
RETURNING TEMPERATURES TO SEASONAL LEVELS BY SUNDAY.
&&
.NEAR TERM /THROUGH TUESDAY/...
AS OF 245 AM EDT...RADAR AND SATELLITE OBSERVATIONS SHOW A STEADILY
DIMINISHING MCS OVER CENTRAL KY AND NRN TN EARLY THIS MORNING. THIS
ACTIVITY WILL MOVE INTO A REGION OF LESSER INSTABILITY ACROSS ERN TN
THROUGH THE EARLY MORNING HOURS AND WILL GRADUALLY DISSIPATE. THIS
IS IN AGREEMENT WITH THE LATEST HRRR RUNS...WHICH HAVE LITTLE TO NO
SIMULATED REFLECTIVITY REACHING THE WRN MOUNTAINS AROUND DAYBREAK.
OTHERWISE...THE MAIN STORY WILL BE THE BUILDING HEAT AS 500 MB
HEIGHTS INCREASE FROM THE SOUTHERN PLAINS TO THE SOUTHEAST TODAY
THROUGH TONIGHT. THE HEAT INDEX FORECAST REMAINS SOMEWHAT
CHALLENGING DUE MAINLY TO DEWPOINT UNCERTAINTY GIVEN THE HISTORY OF
SLIGHT MIXING EACH AFTERNOON IN THIS REGIME. ANTICIPATE PLENTY OF
MID TO UPPER 90S EAST OF THE MTNS...BUT WITH HEAT INDEX VALUES
GENERALLY UPPER 90S TO LOWER 100S...WITH JUST A SLIVER OF 105 ACROSS
THE EXTREME LOWER PIEDMONT. GREENWOOD COUNTY WILL BE MOST AT RISK OF
105 THIS AFTN AND A HEAT ADVISORY WILL BE POSTED THERE.
REGARDING CONVECTION...INITIAL DEVELOPMENT ON THE CONVECTION
ALLOWING MODELS IS FOCUSED ALONG THE ERN SLOPES OF THE MTNS AGAIN
THIS AFTERNOON AND THIS IS CONSISTENT WITH THE REGION OF BEST LOW
LEVEL CONVERGENCE. ALL MODEL PROFILES HAVE QUITE A BIT OF CIN AND
CAPPING TO OVERCOME TODAY...THE GFS MORE SO THAN THE NAM. THE GFS
PROFILES AND LOW LEVEL DEWPOINTS ARE PREFERRED AND THIS SOLUTION OF
LESS COVERAGE WILL BE FOLLOWED...WITH MAINLY A MTN FOCUS...POSSIBLY
TRANSITIONING TO THE PIEDMONT IN LEE TROUGH CONVERGENCE TOWARD
EVENING. STRONG TO SEVERE STORMS WILL BE POSSIBLE WITH ANYTHING THAT
BREAKS THE CAP GIVEN THE STEEP LAPSE RATES ALOFT. ANY CONVECTION
WILL DIMINISH QUICKLY WITH THE LOSS OF HEATING THIS EVENING...WITH
JUST DEBRIS CLOUDS AROUND DURING THE WARM TONIGHT PERIOD.
&&
.SHORT TERM /TUESDAY NIGHT THROUGH WEDNESDAY NIGHT/...
AS OF 305 AM MONDAY...DEEP SUBTROPICAL RIDGING REMAINS ACROSS THE FA
TUE THRU WED WITH SUBTLE LOWERING OF HEIGHTS BEGINNING TUE AFTERNOON
AND DECREASING MORESO WED WITH FRONTAL SYSTEM PUSHING IN FROM THE
NORTH. TUES WILL BE THE DRIER AND WARMER DAY. THE FLOW BELOW H9 WILL
BRING LOW-END MOISTURE ADV TO THE WRN ZONES TUE LIMITING PULSE
SHRA/TSTM ACTIVITY ACROSS THE SW MTNS. MEANWHILE...A DISTINCTLY
STRONGER W/LY FLOW WITHIN THE H9/H8 LAYER WILL ALIGN CORRECTLY FOR
DOWNSLOPE WARMING. WITH DEEP NEG OMEGA AND HIGH INSOL IN PLACE...MAX
TEMPS WILL REACH ARND 100 F ACROSS THE PIEDMONT REGIONS. DEWPOINTS
WILL ALSO MIX OUT THE BEST IN THESE AREAS KEEPING THE BETTER CHANCE
OF 105 F HI/S ACROSS THE SRN TIER COUNTIES. THE SAME GENERAL
SCENARIO GOES FOR WED...BUT A FRONT STALLING OUT ACROSS THE NRN
ZONES WILL CREATE A LLVL COL AND REDUCE THE AMOUNT OF ADDED MECH
HEAT. THUS HI/S WILL STILL BE HIGH...BUT THE 105 F AREAS WILL BE
MORE LIMITED. BOTH DAYS WILL RECIEVE A GENERAL HWO MENTION.
WITH THE AFOREMENTIONED FRONTAL SYSTEM PUSHING IN EARLY WED
MORNING...NOCTURNAL CONVEC ACTIVITY WILL CONTINUE WITHIN GOOD
ELCAPE. THIS BNDRY WILL PROVIDE AND GOOD FOCUSING ZONE FOR AFTERNOON
STORMS ACROSS THE MTNS AND ARND THE I-40 COORIDOR. MODEL SOUNDINGS
FOR KHKY BECOME HIGHLY SATURATED WED AFTERNOON WHILE WARM CLOUD
LAYERS DEEPEN...SO A HYDRO CONCERN IS POSSIBLE GIVEN LIMITED STORM
MOTIONS.
&&
.LONG TERM /THURSDAY THROUGH SUNDAY/...
AS OF 330 AM EDT MONDAY...WELL ABOVE NORMAL TEMPS ARE IN STORE FOR
THU AND FRI HOWEVER MAXES WILL LOWER ENUF FOR HI/S TO BECOME LESS OF
A CONCERN CWFA/WIDE. THE UPPER RIDGE CONFIG REMAINS RELATIVELY
UNCHANGED THU ALLOWING GOOD HEATING WITH A LEE TROF DEVELOPING AND
THE LLVL FLOW BECOMES MORE SW/LY INCREASING MOISTURE FLUX INTO THE
MTNS. THE PREVIOUS DAY/S FRONTAL SYSTEM BECOMES DIFFUSE SO THE
BETTER CHANCE POPS WILL BE ACROSS THE MTNS...MAINLY A CLIMO PATTERN
OVER THE FA. THINGS BEGIN TO CHANGE FRI AS UPPER HEIGHTS BECOME MORE
CYCLONIC WITH A LARGE SCALE TROF DEVELOPING TO THE WEST. THIS WILL
HAVE THE EFFECT OF MAINTAINING NOCTURNAL CONVEC THRU THE
WEEKEND...MAINLY MTNS AND ENHANCE THE LEE TROF. AS FAR AS POPS...A
BIT ABOVE CLIMO FRI/SAT AS TROF AXIS REMAINS EAST OF THE CWFA. THE
TROF WILL PUSH A COLD FRONT INTO THE AREA LATE SAT...BUT BY THIS
TIME THE DEEPER DYNAMICS WILL BE NORTH OF THE FA...SO THE FRONT WILL
LIKELY BECOME DISRUPTED AS IT CROSSES THE MTNS. MAX TEMPS OVER THE
WEEKEND WILL BE NOTICEABLY COOLER ESP SUN WITH NEAR NORMAL VALUES
RETURNING.
&&
.AVIATION /08Z MONDAY THROUGH FRIDAY/...
AT KCLT...ANTICIPATE MAINLY HIGH LEVEL DEBRIS CLOUDS THROUGH THE
MORNING HOURS. MODEL PROFILES HAVE JUST ENOUGHT CIN AND CAPPING TO
LARGELY PRECLUDE A THUNDER MENTION TODAY...ALTHOUGH A FEW TSTMS WILL
BE POSSIBLE IF STRONGER CONVERGENCE DEVELOPS IN A LEE TROUGH. WINDS
WILL BE LIGHT AND SOMEWHAT VARIABLE...GENERALLY NE THIS MORNING AND
SRLY FROM MIDDAY ONWARD.
ELSEWHERE...ISOLD TO SCATTERED TSTMS COULD DEVELOP NEAR KAVL ONCE
AGAIN IN LOW LEVEL WIND FIELD CONVERGENCE. PROFILES REMAIN GENERALLY
CAPPED WITH DECENT CIN FOR THE BULK OF THE DAY...BUT KAVL WILL STAND
THE BEST CHANCE OF SOMETHING FORMING NEARBY GIVEN THE TERRAIN
INFLUENCE. EXPECT MOSTLY HIGH DEBRIS CLOUDS THIS MORNING FROM THE
UPSTREAM MCS...WITH JUST FEW TO SCT HIGH BASED CUMULUS FOR
THE AFTERNOON AND EARLY EVENING HOURS ALONG WITH MORE DEBRIS CLOUDS
LATE FROM ANY MTN CONVECTION. LIGHT WINDS WILL TURN FROM NE TO SRLY
THROUGH THE COURSE OF THE DAY...EXCEPT STAYING MAINLY NW AT KAVL.
BRIEF MORNING VALLEY FOG WILL BE POSSIBLE AROUND DAYBREAK IF THE
HIGH LEVEL DEBRIS CLOUDS DO NOT APPRECIABLY THICKEN.
OUTLOOK...ISOLD TO SCT DIURNAL TSTM CHANCES WILL CONTINUE THROUGH
THE WEEK IN THE WARM AIRMASS. PRECIPITATION CHANCES WILL INCREASE
LATE IN THE WEEK AS A FRONT APPROACHES FROM THE NW. MORNING
RESTRICTIONS DUE TO FOG AND/OR STRATUS ARE POSSIBLE...PARTICULARLY
WHERE HEAVY RAIN FELL THE PREVIOUS DAY...AND MOST LIKELY IN THE MTN
VALLEYS.
CONFIDENCE TABLE...
07-13Z 13-19Z 19-01Z 01-06Z
KCLT HIGH 100% HIGH 100% HIGH 100% HIGH 100%
KGSP HIGH 100% HIGH 100% HIGH 100% HIGH 100%
KAVL HIGH 100% HIGH 100% HIGH 100% HIGH 100%
KHKY HIGH 100% HIGH 100% HIGH 100% HIGH 100%
KGMU HIGH 100% HIGH 100% HIGH 100% HIGH 100%
KAND HIGH 100% HIGH 100% HIGH 100% HIGH 100%
THE PERCENTAGE REFLECTS THE NUMBER OF GUIDANCE MEMBERS AGREEING
WITH THE SCHEDULED TAF ISSUANCE FLIGHT RULE CATEGORY. COMPLETE HOURLY
EXPERIMENTAL AVIATION FORECAST CONSISTENCY TABLES AND ENSEMBLE FORECASTS
ARE AVAILABLE AT THE FOLLOWING LINK: (MUST BE LOWER CASE)
WWW.WEATHER.GOV/GSP/AVIATION_TABLES
&&
.CLIMATE...
RECORD MAXIMUM TEMPERATURES FOR THIS WEEK...WITH YEARS IN WHICH THE
VALUES WERE LAST REACHED.
MONDAY JUNE 22...
AVL 94 1964
CLT 98 1956
GSP 99 2006
TUESDAY JUNE 23...
AVL 93 1988
CLT 98 1988
GSP 99 1988
WEDNESDAY JUNE 24...
AVL 94 1952
CLT 102 1930
GSP 100 1952
THURSDAY JUNE 25...
AVL 96 1952
CLT 102 1914
GSP 101 1952
&&
.GSP WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
NC...NONE.
SC...HEAT ADVISORY FROM NOON TODAY TO 7 PM EDT THIS EVENING FOR
SCZ019.
&&
$$
SYNOPSIS...SBK
NEAR TERM...HG
SHORT TERM...SBK
LONG TERM...SBK
AVIATION...HG
CLIMATE...WIMBERLEY
AREA FORECAST DISCUSSION
NWS GREENVILLE-SPARTANBURG SC
158 AM EDT MON JUN 22 2015
.SYNOPSIS...
DEEP HIGH PRESSURE WILL PERSIST OVER THE REGION THROUGH THE MIDDLE OF
THE WEEK. HOT TEMPERATURES WILL ALSO RETURN AS A STALLED FRONT
REMAINS NORTH OF THE FORECAST AREA. AN UPPER TROF IS EXPECTED TO
MOVE TOWARDS THE REGION OVER THE WEEKEND BRINGING COOLER
TEMPERATURES AND INCREASED CHANCES FOR WIDESPREAD THUNDERSTORMS.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 145 AM EDT...RADAR AND SATELLITE OBSERVATIONS SHOW A GRADUALLY
DIMINISHING MCS OVER CENTRAL KY AND NRN TN EARLY THIS MORNING. THIS
ACTIVITY WILL BE MOVING INTO A REGION OF LESSER INSTABILITY ACROSS
ERN TN THROUGH THE EARLY MORNING HOURS AND IT SHOULD GRADUALLY
DIMINISH. THE LATEST HRRR RUNS HAVE LITTLE TO NO SIMULATED
REFLECTIVITY REACHING THE WRN MOUNTAINS AROUND DAYBREAK...SO THE
OVERNIGHT FORECAST WILL BE DRY.
OTHERWISE...THE MAIN STORY WILL BE THE BUILDING HEAT AS 500 MB
HEIGHTS INCREASE FROM THE SOUTHERN PLAINS TO THE SOUTHEAST TODAY
THROUGH TONIGHT. THE HEAT INDEX FORECAST REMAINS SOMEWHAT
CHALLENGING DUE MAINLY TO DEWPOINT UNCERTAINTY GIVEN THE HISTORY OF
SLIGHT MIXING EACH AFTERNOON IN THIS REGIME. ANTICIPATE PLENTY OF
MID TO UPPER 90S EAST OF THE MTNS...BUT WITH HEAT INDEX VALUES
GENERALLY UPPER 90S TO LOWER 100S...WITH JUST A SLIVER OF 105 ACROSS
THE EXTREME LOWER PIEDMONT. GREENWOOD COUNTY WILL BE MOST AT RISK OF
105 THIS AFTN AND A HEAT ADVISORY WILL BE WEIGHED THERE AND IN
NEARBY PIEDMONT ZONES.
REGARDING CONVECTION...INITIAL DEVELOPMENT ON THE CONVECTION
ALLOWING MODELS IS FOCUSED ALONG THE ERN SLOPES OF THE MTNS AGAIN
THIS AFTERNOON AND THIS IS CONSISTENT WITH THE REGION OF BEST LOW
LEVEL CONVERGENCE. ALL MODEL PROFILES HAVE QUITE A BIT OF CIN AND
CAPPING TO OVERCOME TODAY...BUT THE GFS MORE SO THAN THE NAM. THE
GFS PROFILES AND LOW LEVEL DEWPOINTS ARE PREFERRED AND THIS SOLUTION
OF LESS COVERAGE WILL BE FOLLOWED...WITH MAINLY A MTN
FOCUS...POSSIBLY TRANSITIONING TO THE PIEDMONT IN LEE TROUGH
CONVERGENCE TOWARD EVENING. STRONG TO SEVERE STORMS WILL BE POSSIBLE
WITH ANYTHING THAT BREAKS THE CAP GIVEN THE STEEP LAPSE RATES ALOFT.
ANY CONVECTION WILL DIMINISH QUICKLY WITH THE LOSS OF HEATING THIS
EVENING...WITH JUST DEBRIS CLOUDS AROUND DURING THE WARM TONIGHT
PERIOD.
&&
.SHORT TERM /TUESDAY THROUGH WEDNESDAY/...
AS OF 200 PM SUNDAY...MON NIGHT INTO EARLY TUE A WELL DEVELOPED LOW
PRESSURE SYSTEM WILL CROSS THE NRN GREAT LAKES...BRINGING A COLD
FRONT INTO THE MID MISSISSIPPI VALLEY. MEANWHILE BROAD RIDGE OVER THE
SRN TIER OF THE CONUS WILL PERSIST. AS THE LOW PASSES NORTH OF THE
FCST AREA...SLIGHT TROUGHING COULD OCCUR AS FAR SWD AS THE
CAROLINAS...BUT THIS IS REALLY ONLY INDICATED BY THE GFS. ONCE
DIURNAL ACTIVITY DIES DOWN MON EVENING WE SHOULD BE DRY UNTIL THE
RAMP-UP WITH HEATING ON TUE. SUBSIDENCE CAPPING WILL PROBABLY KEEP
THE PIEDMONT DRY TUE BUT A CHANCE RETURNS OVER THE MTNS.
INTERESTINGLY THE NAM BRINGS THE SEA BREEZE AS FAR NORTH AS OUR SRN
SC/GA ZONES NEAR SUNSET...BUT CONFIDENCE IS TOO LOW ON THIS TO
REFLECT IT IN THE FCST. THIS COULD HOWEVER PROVIDE ENOUGH LIFT TO
OVERCOME A WEAK CAP.
WHILE THE ACTUAL FRONT WILL STILL BE MAKING SWD PROGRESS ACRS THE
OHIO VALLEY THRU THE DAY IT IS UNLIKELY TO ENCROACH ON OUR AREA UNTIL
WED AT THE EARLIEST. NAM SHOWS IT MARCHING SWD OVERNIGHT TUE NIGHT
BUT IT APPEARS WEAK ENOUGH IT WOULD MORE LIKELY STALL...BEFORE
PERHAPS ARRIVING AFTER DAYBREAK. SOUTHERLY FLOW AROUND THE INCUMBENT
HIGH PRESSURE IS TOO STRONG FOR THE FRONT THOUGH...AND IT WASHES OUT
OVER THE AREA WED. PROFILES ARE SLIGHTLY MORE UNSTABLE AND UNCAPPED
EAST OF THE MTNS SO MENTIONABLE POPS ARE INCLUDED ACRS THE CWFA.
VERTICAL PROFILES HAVE SUFFICIENT DRY AIR ALOFT THAT ISOLATED PULSE
STORMS PRODUCING DAMAGING WINDS MIGHT OCCUR DURING PEAK HEATING.
MAX TEMPS WILL CONTINUE TO BE 7 TO 10 DEGREES ABOVE NORMAL. CHOSE
BLENDS OF T/TD GUIDANCE BASED ON THOSE THAT VERIFIED BEST WITH THE
HOT CONDITIONS LAST WEEK. THE AMOUNT OF MIXING THAT OCCURS WILL
AFFECT TD/S BUT THE BEST VERIFYING GUIDANCE REFLECTS LITTLE OF THIS.
PORTIONS ALONG AND SOUTH OF I-85 WILL SEE HEAT INDICES PEAK NEAR 105
BOTH DAYS...AND ADVISORIES CANNOT BE RULED OUT. WILL ADD EXCESSIVE
HEAT WORDING TO THE HWO FOR WED.
&&
.LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/...
AS OF 205 PM EDT SUNDAY...THE MEDIUM RANGE FCST PICKS UP AT 00Z ON
THURSDAY WITH BROAD UPPER RIDGING OVER THE CENTRAL AND EASTERN CONUS
AND UPPER TROFFING OVER SE CANADA. OVER THE NEXT COUPLE OF
DAYS...HEIGHTS GRADUALLY LOWER WHILE MULTIPLE LOBES OF EMBEDDED
SHORTWAVE ENERGY RIPPLE BY TO OUR NORTH. OVER THE WEEKEND...THE LONG
RANGE GUIDANCE HAS THE UPPER RIDGE AMPLIFYING OVER THE WESTERN CONUS
WHILE A SOUTHERN STREAM UPPER TROF DIGS DOWN ACROSS THE MISS RIVER
VALLEY AND TOWARDS THE CWFA. AT THE SFC...THE BERMUDA HIGH WILL
REMAIN IN CONTROL OF THE SYNOPTIC PATTERN FOR THE REGION THRU THE
PERIOD WITH NUMEROUS WEAK LOWS BEING GENERATED OVER THE PLAINS AND
PROPAGATING EASTWARD. THESE SYSTEMS SHOULD REMAIN TO OUR NORTH WITH
THEIR ASSOCIATED FRONTS MOSTLY WASHING OUT AS THEY DRIFT SOUTHWARD.
IT DOES APPEAR THAT SOME DEGREE OF LEE TROFFING WILL DEVELOP EACH
DAY WITH IT BEING MORE PRONOUNCED ON SAT AND SUN AS THE LOWS
GENERATED APPEAR TO BE MORE ORGANIZED. AS FOR THE SENSIBLE
FCST...DIURNAL CONVECTION IS POSSIBLE EACH DAY WITH CHANCES
GENERALLY HIGHER OVER THE MTS AND NC FOOTHILLS. CHANCES INCREASE FOR
SAT AND SUN WITH THE INCREASING DEEP LYR MOISTURE OVER THE REGION
AND BETTER UPPER LVL SUPPORT OVERHEAD. TEMPS START OUT WELL ABOVE
CLIMATOLOGY AND GRADUALLY DECREASE THRU THE PERIOD WITH VALUES
ENDING RIGHT AROUND NORMAL...IF NOT JUST ABOVE...BY DAY 7.
&&
.AVIATION /06Z MONDAY THROUGH FRIDAY/...
AT KCLT...ANTICIPATE MAINLY HIGH LEVEL DEBRIS CLOUDS THROUGH THE
MORNING HOURS. MODEL PROFILES HAVE JUST ENOUGHT CIN AND CAPPING TO
LARGELY PRECLUDE A THUNDER MENTION TODAY...ALTHOUGH A FEW TSTMS WILL
BE POSSIBLE IF STRONGER CONVERGENCE DEVELOPS IN A LEE TROUGH. WINDS
WILL BE LIGHT AND SOMEWHAT VARIABLE...GENERALLY NE THIS MORNING AND
SRLY FROM MIDDAY ONWARD.
ELSEWHERE...ISOLD TO SCATTERED TSTMS COULD DEVELOP NEAR KAVL ONCE
AGAIN IN LOW LEVEL WIND FIELD CONVERGENCE. PROFILES REMAIN GENERALLY
CAPPED WITH DECENT CIN FOR THE BULK OF THE DAY...BUT KAVL WILL STAND
THE BEST CHANCE OF SOMETHING FORMING NEARBY GIVEN THE TERRAIN
INFLUENCE. EXPECT MOSTLY HIGH DEBRIS CLOUDS THIS MORNING FROM THE
UPSTREAM MCS AND EARLIER CONVECTION...WITH JUST FEW TO SCT HIGH
BASED CUMULUS FOR THE AFTERNOON AND EARLY EVENING HOURS ALONG WITH
MORE DEBRIS CLOUDS LATE FROM ANY MTN CONVECTION. LIGHT WINDS WILL
TURN FROM NE TO SRLY THROUGH THE COURSE OF THE DAY..EXCEPT STAYING
MAINLY NW AT KAVL. BRIEF MORNING VALLEY FOG WILL BE POSSIBLE AROUND
DAYBREAK IF THE HIGH LEVEL DEBRIS CLOUDS DO NOT APPRECIABLY THICKEN.
OUTLOOK...ISOLD TO SCT DIURNAL TSTM CHANCES WILL CONTINUE THROUGH
THE WEEK IN THE WARM AIRMASS. PRECIPITATION CHANCES WILL INCREASE
LATE IN THE WEEK AS A FRONT APPROACHES FROM THE NW. MORNING
RESTRICTIONS DUE TO FOG AND/OR STRATUS ARE POSSIBLE...PARTICULARLY
WHERE HEAVY RAIN FELL THE PREVIOUS DAY...AND MOST LIKELY IN THE MTN
VALLEYS.
CONFIDENCE TABLE...
06-12Z 12-18Z 18-24Z 00-06Z
KCLT HIGH 100% HIGH 100% HIGH 100% HIGH 100%
KGSP HIGH 100% HIGH 100% HIGH 100% HIGH 100%
KAVL HIGH 100% HIGH 100% HIGH 100% HIGH 100%
KHKY HIGH 100% HIGH 100% HIGH 100% HIGH 100%
KGMU HIGH 100% HIGH 100% HIGH 100% HIGH 100%
KAND HIGH 100% HIGH 100% HIGH 100% HIGH 100%
THE PERCENTAGE REFLECTS THE NUMBER OF GUIDANCE MEMBERS AGREEING
WITH THE SCHEDULED TAF ISSUANCE FLIGHT RULE CATEGORY. COMPLETE HOURLY
EXPERIMENTAL AVIATION FORECAST CONSISTENCY TABLES AND ENSEMBLE FORECASTS
ARE AVAILABLE AT THE FOLLOWING LINK: (MUST BE LOWER CASE)
WWW.WEATHER.GOV/GSP/AVIATION_TABLES
&&
.CLIMATE...
RECORD MAXIMUM TEMPERATURES FOR THIS WEEK...WITH YEARS IN WHICH THE
VALUES WERE LAST REACHED.
MONDAY JUNE 22...
AVL 94 1964
CLT 98 1956
GSP 99 2006
TUESDAY JUNE 23...
AVL 93 1988
CLT 98 1988
GSP 99 1988
WEDNESDAY JUNE 24...
AVL 94 1952
CLT 102 1930
GSP 100 1952
THURSDAY JUNE 25...
AVL 96 1952
CLT 102 1914
GSP 101 1952
&&
.GSP WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
NC...NONE.
SC...NONE.
&&
$$
SYNOPSIS...JPT
NEAR TERM...HG
SHORT TERM...WIMBERLEY
LONG TERM...JPT
AVIATION...HG
CLIMATE...
AREA FORECAST DISCUSSION
NWS MEMPHIS TN
1022 PM CDT TUE JUN 23 2015
.UPDATE...EVENING UPDATE
IT NOW LOOKS MORE LIKELY THAT THUNDERSTORMS WILL CONTINUE
OVERNIGHT PUSHING SOUTH ACROSS MOST IF NOT ALL OF THE MIDSOUTH.
ADJUSTED POPS ACCORDINGLY. STORMS WILL MAINLY IMPACT WEST
TENNESSEE AND NORTH MISSISSIPPI...BUT CANNOT BE RULED OUT
ANYWHERE. FREQUENT LIGHTENING AND VERY HEAVY RAINFALL CAN BE
EXPECTED. LOCALIZED FLOODING IS POSSIBLE. WIDESPREAD SEVERE
WEATHER IS NOT ANTICIPATED AT THIS TIME.
30
&&
.PREV DISCUSSION... /ISSUED 719 PM CDT TUE JUN 23 2015/
UPDATE...EVENING UPDATE.
DISCUSSION...
INCREASED POPS ACROSS WEST TENNESSEE...THE MISSOURI BOOTHEEL AND
NORTHEAST ARKANSAS. DON`T THINK THERE IS ANY REAL SEVERE THREAT
BUT LOCALLY HEAVY RAIN AND FREQUENT LIGHTNING IS LIKELY. STORMS
SHOULD DIMINISH IN BOTH INTENSITY AND COVERAGE AFTER SUNSET.
PREV DISCUSSION... /ISSUED 623 PM CDT TUE JUN 23 2015/
CURRENTLY...STRONG UPPER RIDGE EXTENDS FROM THE SOUTHERN PLAINS
INTO THE MIDSOUTH. MEANWHILE A WEAK COLD FRONT HAS PUSHED INTO
SOUTHERN MISSOURI AND WESTERN KY...JUST NORTH OF THE MIDSOUTH.
VERY WARM AIR HAS PUSHED INTO THE MIDSOUTH WITH TEMPS IN THE MID
90S ACROSS MUCH OF THE AREA. SURFACE DEWPOINTS ARE POOLING ACROSS
THE REGION...SOUTH OF THE COLD FRONT...WITH READINGS IN THE MID
TO SOMETIMES UPPER 70S. THIS IS CREATING HEAT INDEX VALUES ABOVE
105 ACROSS MUCH OF THE MIDSOUTH. HAVE EXPANDED THE HEAT ADVISORY
TO COVER MOST OF THE MIDSOUTH THIS AFTERNOON INTO WEDNESDAY.
THE HRRR HAS BEEN TRYING TO DEVELOP CONVECTION ALONG THE WEAK COLD
FRONT TO THE NORTH FOR THE LAST FEW HOURS BUT IT HAS NOT HAPPENED
YET. GIVEN THE WEAK CAP AND SBCAPES AROUND 5000 J/KG THERE IS
STILL THE POSSIBILITY OF ISOLATED STORMS DEVELOPING OVER THE NEXT
FEW HOURS.
TONIGHT...ANY CONVECTION WILL DISSIPATE BY 02Z OR SO WITH MOSTLY
CLEAR SKIES AND WARM TEMPERATURES OVERNIGHT. LOWS IN THE 70S.
WEDNESDAY...ANOTHER VERY HOT AND HUMID DAY WITH THE UPPER RIDGE
CENTERED OVER THE AREA. EXPECT HIGHS IN THE MID 90S AND DEWPOINTS
IN THE MID 70S. THE HEAT ADVISORY HAS BEEN EXTENDED THROUGH 7 PM
THURSDAY FOR MOST OF THE MIDSOUTH FOR HEAT INDICES EXCEEDING 105
DEGREES WEDNESDAY AFTERNOON. AN ISOLATED AFTERNOON STORM COULD
OCCUR ANYWHERE BUT THE BEST CHANCE WILL PROBABLY BE ACROSS NORTH
MISSISSIPPI.
THURSDAY...THE UPPER RIDGE WEAKENS A BIT ON THURSDAY BUT STILL
HOT AND HUMID. HEAT ADVISORIES MAY NEED TO BE EXTENDED. STILL VERY
WARM AIRMASS ACROSS THE REGION WITH 925MB TEMPS OF 28C ACROSS MUCH
OF THE AREA. MODELS ARE POINTING TOWARD INCREASING MOISTURE MOVING
UP FROM THE GULF WITH BETTER CHANCES OF AFTERNOON SHOWERS AND
THUNDERSTORMS ACROSS NORTH MISSISSIPPI.
FRIDAY AND SATURDAY...MAJOR PATTERN SHIFT AS THE UPPER RIDGE
BREAKS DOWN AND A DEEP UPPER TROF DEVELOPS OVER THE EASTERN U.S.
A COLD FRONT WILL PUSH THROUGH THE AREA FRIDAY INTO SATURDAY
MORNING WITH NUMEROUS SHOWERS AND THUNDERSTORMS. A FEW STRONG TO
SEVERE STORMS ARE POSSIBLE DURING THIS PERIOD. MUCH COOLER AND
DRIER WEATHER WILL SETTLE OVER THE REGION LATER SATURDAY INTO
EARLY NEXT WEEK AS THE REGION REMAINS UNDER THE INFLUENCE OF THE
UNSEASONABLE DEEP UPPER TROF.
SJM
&&
.AVIATION...00Z TAF CYCLE
VFR CONDITIONS EXPECTED TO PERSIST THROUGH MUCH OF THE PERIOD.
ISOLATED/SCATTERED SHOWERS AND THUNDERSTORMS MAY HAVE THE
POTENTIAL TO PRODUCE VCTS AT MKL/JBR AND PERHAPS MEM EARLY THIS
EVENING AND AT TUP WEDNESDAY AFTERNOON. LIGHT W/NW WINDS WILL VEER
N ON WEDNESDAY.
CJC
&&
.MEG WATCHES/WARNINGS/ADVISORIES...
AR...HEAT ADVISORY FROM NOON TO 7 PM CDT WEDNESDAY FOR CLAY-CRAIGHEAD-
CRITTENDEN-CROSS-GREENE-LAWRENCE-LEE AR-MISSISSIPPI-
PHILLIPS-POINSETT-RANDOLPH-ST. FRANCIS.
MO...HEAT ADVISORY FROM NOON TO 7 PM CDT WEDNESDAY FOR DUNKLIN-
PEMISCOT.
MS...HEAT ADVISORY FROM NOON TO 7 PM CDT WEDNESDAY FOR ALCORN-BENTON
MS-CALHOUN-CHICKASAW-COAHOMA-DESOTO-ITAWAMBA-LAFAYETTE-LEE
MS-MARSHALL-MONROE-PANOLA-PONTOTOC-PRENTISS-QUITMAN-
TALLAHATCHIE-TATE-TIPPAH-TISHOMINGO-TUNICA-UNION-YALOBUSHA.
TN...HEAT ADVISORY FROM NOON TO 7 PM CDT WEDNESDAY FOR CHESTER-
CROCKETT-DYER-FAYETTE-HARDEMAN-HARDIN-HAYWOOD-LAKE-
LAUDERDALE-MADISON-MCNAIRY-OBION-SHELBY-TIPTON.
&&
$$
AREA FORECAST DISCUSSION
NWS NASHVILLE TN
939 PM CDT TUE JUN 23 2015
.UPDATE...
18Z GFS RUN SHOWING UPPER HIGH OVER EASTERN OK WITH THE RIDGE AXIS
EXTENDING ESE ACROSS NRN AL. CURVATURE AND SHEAR NOTED UPSTREAM
WITH VORT MAX NOW MOVING THROUGH NRN MIDDLE TN. PVA IS CURRENTLY
ACROSS SOUTHERN MIDDLE TN AND IS COUPLING WITH DIVERGENCE
ALOFT...JUST NORTH OF THE RIDGE AXIS. MEAN 700-500MB FLOW IS
RATHER WEAK AND THUS STORMS ARE SLOW MOVERS. PWATS ARE STILL
RATHER HIGH AND ISOL AREAS OF FLOODING IS ONGOING.
FOR THE UPDATE...WILL INCREASE POPS ACROSS SOUTHWESTERN AREAS AND
THE SOUTHERN AND CENTRAL PLATEAU...PER ONGOING CONVECTION. WILL
ALSO MAKE A SLIGHT UPWARD TWEAK WITH THE SKY GRIDS.
&&
.PREV DISCUSSION... /ISSUED 801 PM CDT TUE JUN 23 2015/
UPDATE...
WILL ISSUE A QUICK UPDATE AND INCREASE POPS INTO THE CHANCE
CATEGORY AREA WIDE BETWEEN NOW AND 03Z. ALSO...WILL INCLUDE FOG
ACROSS THE PLATEAU FOR THE AFT MIDNIGHT PERIOD.
WILL ALLOW THE SLIGHT CHANCE TO COVER THE PRECIP CHANCES FROM 03Z
TO 06Z. THE FRONT IS APPROACHING THE KY/TN BORDER AT THIS TIME. IT
IS QUITE WEAK AND THE UPPER RIDGING BUILDING IN FROM THE WEST IS
STRENGTHENING. THEREFORE...THIS ACTIVITY SHOULD DIE OUT AS THE
NIGHT PROGRESSES. HRRR AND ISC BOTH CONCUR.
UPDATE OUT SHORTLY.
PREV DISCUSSION... /ISSUED 703 PM CDT TUE JUN 23 2015/
UPDATE...FOR 00Z AVIATION DISCUSSION.
AVIATION UPDATE...00Z AVIATION DISCUSSION.
SFC FRONT IS EXPECTED TO MOVE S OF MID STATE BY 24/06Z...WHICH WILL USHER IN
SOME DRIER AIR TO THE AREA...BUT BEFORE THAT...DIURNAL DRIVEN ISO SHWRS/TSTMS
SHOULD PERSIST UNTIL AT LEAST 24/02Z-24/03Z. WITH UNCERTAINTIES IN DEVELOPMENT/
IMPACTS OF SHWRS/TSTMS AT PARTICULAR TAF SITES...WILL ADDRESS CURRENTLY WITH
PREVAILING VCTS REMARKS ONLY. SOME MVFR FOG INDUCED VSBYS/CEILINGS POSSIBLE
CKV/BNA AROUND 24/06Z-24/15Z PER SUITABLE DEWPOINT DEPRESSIONS RESULTING
FROM LOW LEVEL MOISTURE POOLING POTENTIAL ALONG WITH LIGHTER WINDS...AIDED
BY POTENTIALLY LOCALLY CLRING SKIES. BEST LOW LEVEL MOISTURE POOLING POTENTIAL
WILL BE NEAR CSV WHERE LIFR TEMPO FOG INDUCED CEILINGS/VSBYS POSSIBLE. WITH
DRIER AIR WORKING INTO MID STATE THRU 24/24Z...BELIEVE POTENTIAL FOR ISO
SHWRS/TSTMS WILL BE OVERALL LESS THAN THIS AFTERNOON`S COVERAGE AND WILL
MENTION ONLY SCT CU...SCT/BKN AC...AND SCT/BKN CI.
PREV DISCUSSION.../ISSUED 404 PM CDT TUE JUN 23 2015/
DISCUSSION...
TEMPS AND DEWPOINTS SOARING AGAIN THIS AFTERNOON...HEAT INDICES
WILL BE BETWEEN 100 AND 104 TODAY. A FEW STORMS HAVE BEEN MOVING
ACROSS NORTHERN KENTUCKY THIS AFTERNOON AHEAD OF A COLD FRONT
SLOWLY MAKING ITS WAY THROUGH THE OHIO VALLEY. MODELS INDICATE IT
WILL MAKE IT FAR ENOUGH SOUTH THIS EVENING TO BRING A FEW ISOLATED
SHOWERS AND THUNDERSTORMS TO MIDDLE TENNESSEE...WITH THE BEST
CHANCE FOR PRECIP IN THE NORTHEAST COUNTIES. SOME STORMS MAY
BECOME STRONG WITH GUSTY WINDS AND HEAVY RAIN. WINDS WILL SHIFT
OUT OF THE NORTH OVERNIGHT TONIGHT BRINGING IN SLIGHTLY DRIER
AIR...WHICH LOOKS TO KEEP OUR DEWPOINTS LOW ENOUGH ON WEDNESDAY TO
ALLOW US TO ONCE AGAIN AVOID A HEAT ADVISORY. HOWEVER, THE HEAT
INDICES ARE STILL EXPECTED TO BE IN THE 100 TO 105 RANGE FOR OUR
SOUTHERN COUNTIES...SO WE`LL CONTINUE TO KEEP AN EYE ON DEWPOINTS
AND TEMPS THROUGHOUT THE DAY IN THAT AREA. WITH WEDNESDAY`S DRIER
AIR COMES LOWER POPS WITH ONLY AN AFTERNOON THUNDERSTORM OR TWO
EXPECTED.
DEWPOINTS RECOVER ON THURSDAY AS A SURFACE HIGH PASSES NORTHEAST
OF THE TENNESSEE VALLEY STIRRING UP A LIGHT SOUTHERLY FLOW AND AN
INCREASE IN MOISTURE OVER MIDDLE TENNESSEE. CONSEQUENTLY EXPECT A
FEW MORE SHOWERS AND THUNDERSTORMS THURSDAY AFTERNOON AND EVENING
ALONG WITH HEAT INDICES AROUND ADVISORY CRITERIA...105 TO 108.
WILL HOLD OFF ON ISSUING AN ADVISORY AT THIS TIME UNTIL CONFIDENCE
IS HIGHER.
PRECIP CHANCES INCREASE AS WE HEAD INTO FRIDAY. AN UPPER TROUGH
WILL DEEPEN OVER THE EASTERN U.S. AND SWING A COLD FRONT THROUGH
THE TENNESSEE VALLEY EARLY SATURDAY MORNING. THIS WILL ALLOW FOR
A GOOD FOCUSING MECHANISM FOR THUNDERSTORM DEVELOPMENT. FRIDAY
AFTERNOON INSTABILITY IS HIGH ENOUGH FOR THUNDERSTORM
DEVELOPMENT...HOWEVER THE FRONT WILL BE LOCATED TO THE NORTH OF
THE CWA DURING THIS TIME...SO ANY STORMS WILL LIKELY SPARK DUE TO
AFTERNOON HEATING. ALONG WITH THE LACK OF A FOCUSING
MECHANISM...ORGANIZATION MAY BE LIMITED BY BULK SHEAR VALUES
LESS THAN 30KTS...HOWEVER SOME SEVERE STORMS WILL STILL BE
POSSIBLE WITH THE AMOUNT OF INSTABILITY IN PLACE. PWATS ARE
IMPRESSIVE DURING THIS TIME FRAME WITH VALUES OF 1.9 TO 2.00
INCHES STILL INDICATED ON BOTH THE NAM AND THE GFS...SO EXPECTING
STRONG...POSSIBLY SEVERE STORMS WITH HEAVY RAINFALL FRIDAY
AFTERNOON AND EVENING.
AS THE FRONT APPROACHES ON SATURDAY MORNING BULK SHEAR VALUES
INCREASE TO AROUND 40KTS. COULD SEE A SPIKE IN THUNDERSTORM
ACTIVITY EARLY SATURDAY MORNING ALONG THE FRONTAL BOUNDARY THEN
COOLER TEMPS DURING THE AFTERNOON WITH MOSTLY CLOUDY SKIES BEHIND
THE FRONT. CONDITIONS DRY OUT GOING INTO SUNDAY AS THE PREVIOUS
SYSTEM CONTINUES OFF TO THE EAST AND LEAVES THE MID STATE WITH
MUCH MORE PLEASANT DEWPOINTS AND HIGH TEMPERATURES. SUNDAY LOOKS
TO BE A GREAT DAY TO GET OUTSIDE AND ENJOY TEMPERATURES AROUND 80
WITH DEWPOINTS IN THE LOW 60S. TEMPERATURES GRADUALLY WARM DURING
THE FIRST HALF OF THE WORK WEEK NEXT WEEK AS A WEAK SURFACE HIGH
MOVES ACROSS THE TENNESSEE VALLEY. A CHANCE OF THUNDERSTORMS
CREEPS INTO THE FORECAST BY TUESDAY.
PREV DISCUSSION... /ISSUED 108 PM CDT TUE JUN 23 2015/
AVIATION UPDATE...
SURFACE FRONT JUST NORTH OF THE OHIO RIVER WILL MOVE SOUTHWARD AS
WE GO THROUGH THE AFTERNOON AND INTO TONIGHT. AM LOOKING FOR A LINE
OF CONVECTION TO FIRE OFF ALONG THE OHIO RIVER 20Z-21Z TIME FRAME
AND SINK SOUTHWARD WITH THE LEADING EDGE ALONG THE TENNESSEE/KENTUCKY
BORDER AROUND 00Z AND CONTINUE SOUTHWARD INTO MIDDLE TENNESSEE DURING
THE EVENING. FOR NOW WILL RUN VICINITY THUNDERSTORMS AT TERMINALS
BUT WILL UPDATE ONCE LINE DEVELOPS AND TRY AND TIME IT A LITTLE
BETTER. ALSO...LOOKING FOR SOME LATE NIGHT FOG.
&&
.PRELIMINARY POINT TEMPS/POPS...
NASHVILLE 74 92 73 96 / 30 20 10 20
CLARKSVILLE 72 89 72 94 / 30 20 10 10
CROSSVILLE 70 86 68 90 / 40 20 10 20
COLUMBIA 74 93 73 97 / 30 20 10 20
LAWRENCEBURG 74 93 73 95 / 50 20 10 20
WAVERLY 73 91 73 95 / 30 20 10 20
&&
.OHX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
21
AREA FORECAST DISCUSSION
NWS NASHVILLE TN
801 PM CDT TUE JUN 23 2015
.UPDATE...
WILL ISSUE A QUICK UPDATE AND INCREASE POPS INTO THE CHANCE
CATEGORY AREA WIDE BETWEEN NOW AND 03Z. ALSO...WILL INCLUDE FOG
ACROSS THE PLATEAU FOR THE AFT MIDNIGHT PERIOD.
WILL ALLOW THE SLIGHT CHANCE TO COVER THE PRECIP CHANCES FROM 03Z
TO 06Z. THE FRONT IS APPROACHING THE KY/TN BORDER AT THIS TIME. IT
IS QUITE WEAK AND THE UPPER RIDGING BUILDING IN FROM THE WEST IS
STRENGTHENING. THEREFORE...THIS ACTIVITY SHOULD DIE OUT AS THE
NIGHT PROGRESSES. HRRR AND ISC BOTH CONCUR.
UPDATE OUT SHORTLY.
&&
.PREV DISCUSSION... /ISSUED 703 PM CDT TUE JUN 23 2015/
UPDATE...FOR 00Z AVIATION DISCUSSION.
AVIATION UPDATE...00Z AVIATION DISCUSSION.
SFC FRONT IS EXPECTED TO MOVE S OF MID STATE BY 24/06Z...WHICH WILL USHER IN
SOME DRIER AIR TO THE AREA...BUT BEFORE THAT...DIURNAL DRIVEN ISO SHWRS/TSTMS
SHOULD PERSIST UNTIL AT LEAST 24/02Z-24/03Z. WITH UNCERTAINTIES IN DEVELOPMENT/
IMPACTS OF SHWRS/TSTMS AT PARTICULAR TAF SITES...WILL ADDRESS CURRENTLY WITH
PREVAILING VCTS REMARKS ONLY. SOME MVFR FOG INDUCED VSBYS/CEILINGS POSSIBLE
CKV/BNA AROUND 24/06Z-24/15Z PER SUITABLE DEWPOINT DEPRESSIONS RESULTING
FROM LOW LEVEL MOISTURE POOLING POTENTIAL ALONG WITH LIGHTER WINDS...AIDED
BY POTENTIALLY LOCALLY CLRING SKIES. BEST LOW LEVEL MOISTURE POOLING POTENTIAL
WILL BE NEAR CSV WHERE LIFR TEMPO FOG INDUCED CEILINGS/VSBYS POSSIBLE. WITH
DRIER AIR WORKING INTO MID STATE THRU 24/24Z...BELIEVE POTENTIAL FOR ISO
SHWRS/TSTMS WILL BE OVERALL LESS THAN THIS AFTERNOON`S COVERAGE AND WILL
MENTION ONLY SCT CU...SCT/BKN AC...AND SCT/BKN CI.
PREV DISCUSSION.../ISSUED 404 PM CDT TUE JUN 23 2015/
DISCUSSION...
TEMPS AND DEWPOINTS SOARING AGAIN THIS AFTERNOON...HEAT INDICES
WILL BE BETWEEN 100 AND 104 TODAY. A FEW STORMS HAVE BEEN MOVING
ACROSS NORTHERN KENTUCKY THIS AFTERNOON AHEAD OF A COLD FRONT
SLOWLY MAKING ITS WAY THROUGH THE OHIO VALLEY. MODELS INDICATE IT
WILL MAKE IT FAR ENOUGH SOUTH THIS EVENING TO BRING A FEW ISOLATED
SHOWERS AND THUNDERSTORMS TO MIDDLE TENNESSEE...WITH THE BEST
CHANCE FOR PRECIP IN THE NORTHEAST COUNTIES. SOME STORMS MAY
BECOME STRONG WITH GUSTY WINDS AND HEAVY RAIN. WINDS WILL SHIFT
OUT OF THE NORTH OVERNIGHT TONIGHT BRINGING IN SLIGHTLY DRIER
AIR...WHICH LOOKS TO KEEP OUR DEWPOINTS LOW ENOUGH ON WEDNESDAY TO
ALLOW US TO ONCE AGAIN AVOID A HEAT ADVISORY. HOWEVER, THE HEAT
INDICES ARE STILL EXPECTED TO BE IN THE 100 TO 105 RANGE FOR OUR
SOUTHERN COUNTIES...SO WE`LL CONTINUE TO KEEP AN EYE ON DEWPOINTS
AND TEMPS THROUGHOUT THE DAY IN THAT AREA. WITH WEDNESDAY`S DRIER
AIR COMES LOWER POPS WITH ONLY AN AFTERNOON THUNDERSTORM OR TWO
EXPECTED.
DEWPOINTS RECOVER ON THURSDAY AS A SURFACE HIGH PASSES NORTHEAST
OF THE TENNESSEE VALLEY STIRRING UP A LIGHT SOUTHERLY FLOW AND AN
INCREASE IN MOISTURE OVER MIDDLE TENNESSEE. CONSEQUENTLY EXPECT A
FEW MORE SHOWERS AND THUNDERSTORMS THURSDAY AFTERNOON AND EVENING
ALONG WITH HEAT INDICES AROUND ADVISORY CRITERIA...105 TO 108.
WILL HOLD OFF ON ISSUING AN ADVISORY AT THIS TIME UNTIL CONFIDENCE
IS HIGHER.
PRECIP CHANCES INCREASE AS WE HEAD INTO FRIDAY. AN UPPER TROUGH
WILL DEEPEN OVER THE EASTERN U.S. AND SWING A COLD FRONT THROUGH
THE TENNESSEE VALLEY EARLY SATURDAY MORNING. THIS WILL ALLOW FOR
A GOOD FOCUSING MECHANISM FOR THUNDERSTORM DEVELOPMENT. FRIDAY
AFTERNOON INSTABILITY IS HIGH ENOUGH FOR THUNDERSTORM
DEVELOPMENT...HOWEVER THE FRONT WILL BE LOCATED TO THE NORTH OF
THE CWA DURING THIS TIME...SO ANY STORMS WILL LIKELY SPARK DUE TO
AFTERNOON HEATING. ALONG WITH THE LACK OF A FOCUSING
MECHANISM...ORGANIZATION MAY BE LIMITED BY BULK SHEAR VALUES
LESS THAN 30KTS...HOWEVER SOME SEVERE STORMS WILL STILL BE
POSSIBLE WITH THE AMOUNT OF INSTABILITY IN PLACE. PWATS ARE
IMPRESSIVE DURING THIS TIME FRAME WITH VALUES OF 1.9 TO 2.00
INCHES STILL INDICATED ON BOTH THE NAM AND THE GFS...SO EXPECTING
STRONG...POSSIBLY SEVERE STORMS WITH HEAVY RAINFALL FRIDAY
AFTERNOON AND EVENING.
AS THE FRONT APPROACHES ON SATURDAY MORNING BULK SHEAR VALUES
INCREASE TO AROUND 40KTS. COULD SEE A SPIKE IN THUNDERSTORM
ACTIVITY EARLY SATURDAY MORNING ALONG THE FRONTAL BOUNDARY THEN
COOLER TEMPS DURING THE AFTERNOON WITH MOSTLY CLOUDY SKIES BEHIND
THE FRONT. CONDITIONS DRY OUT GOING INTO SUNDAY AS THE PREVIOUS
SYSTEM CONTINUES OFF TO THE EAST AND LEAVES THE MID STATE WITH
MUCH MORE PLEASANT DEWPOINTS AND HIGH TEMPERATURES. SUNDAY LOOKS
TO BE A GREAT DAY TO GET OUTSIDE AND ENJOY TEMPERATURES AROUND 80
WITH DEWPOINTS IN THE LOW 60S. TEMPERATURES GRADUALLY WARM DURING
THE FIRST HALF OF THE WORK WEEK NEXT WEEK AS A WEAK SURFACE HIGH
MOVES ACROSS THE TENNESSEE VALLEY. A CHANCE OF THUNDERSTORMS
CREEPS INTO THE FORECAST BY TUESDAY.
PREV DISCUSSION... /ISSUED 108 PM CDT TUE JUN 23 2015/
AVIATION UPDATE...
SURFACE FRONT JUST NORTH OF THE OHIO RIVER WILL MOVE SOUTHWARD AS
WE GO THROUGH THE AFTERNOON AND INTO TONIGHT. AM LOOKING FOR A LINE
OF CONVECTION TO FIRE OFF ALONG THE OHIO RIVER 20Z-21Z TIME FRAME
AND SINK SOUTHWARD WITH THE LEADING EDGE ALONG THE TENNESSEE/KENTUCKY
BORDER AROUND 00Z AND CONTINUE SOUTHWARD INTO MIDDLE TENNESSEE DURING
THE EVENING. FOR NOW WILL RUN VICINITY THUNDERSTORMS AT TERMINALS
BUT WILL UPDATE ONCE LINE DEVELOPS AND TRY AND TIME IT A LITTLE
BETTER. ALSO...LOOKING FOR SOME LATE NIGHT FOG.
&&
.PRELIMINARY POINT TEMPS/POPS...
NASHVILLE 74 92 73 96 / 30 20 10 20
CLARKSVILLE 72 89 72 94 / 30 20 10 10
CROSSVILLE 70 86 68 90 / 30 20 10 20
COLUMBIA 74 93 73 97 / 30 20 10 20
LAWRENCEBURG 74 93 73 95 / 30 20 10 20
WAVERLY 73 91 73 95 / 30 20 10 20
&&
.OHX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
21
AREA FORECAST DISCUSSION
NWS MEMPHIS TN
719 PM CDT TUE JUN 23 2015
.UPDATE...EVENING UPDATE.
&&
.DISCUSSION...
INCREASED POPS ACROSS WEST TENNESSEE...THE MISSOURI BOOTHEEL AND
NORTHEAST ARKANSAS. DON`T THINK THERE IS ANY REAL SEVERE THREAT
BUT LOCALLY HEAVY RAIN AND FREQUENT LIGHTNING IS LIKELY. STORMS
SHOULD DIMINISH IN BOTH INTENSITY AND COVERAGE AFTER SUNSET.
&&
.PREV DISCUSSION... /ISSUED 623 PM CDT TUE JUN 23 2015/
CURRENTLY...STRONG UPPER RIDGE EXTENDS FROM THE SOUTHERN PLAINS
INTO THE MIDSOUTH. MEANWHILE A WEAK COLD FRONT HAS PUSHED INTO
SOUTHERN MISSOURI AND WESTERN KY...JUST NORTH OF THE MIDSOUTH.
VERY WARM AIR HAS PUSHED INTO THE MIDSOUTH WITH TEMPS IN THE MID
90S ACROSS MUCH OF THE AREA. SURFACE DEWPOINTS ARE POOLING ACROSS
THE REGION...SOUTH OF THE COLD FRONT...WITH READINGS IN THE MID
TO SOMETIMES UPPER 70S. THIS IS CREATING HEAT INDEX VALUES ABOVE
105 ACROSS MUCH OF THE MIDSOUTH. HAVE EXPANDED THE HEAT ADVISORY
TO COVER MOST OF THE MIDSOUTH THIS AFTERNOON INTO WEDNESDAY.
THE HRRR HAS BEEN TRYING TO DEVELOP CONVECTION ALONG THE WEAK COLD
FRONT TO THE NORTH FOR THE LAST FEW HOURS BUT IT HAS NOT HAPPENED
YET. GIVEN THE WEAK CAP AND SBCAPES AROUND 5000 J/KG THERE IS
STILL THE POSSIBILITY OF ISOLATED STORMS DEVELOPING OVER THE NEXT
FEW HOURS.
TONIGHT...ANY CONVECTION WILL DISSIPATE BY 02Z OR SO WITH MOSTLY
CLEAR SKIES AND WARM TEMPERATURES OVERNIGHT. LOWS IN THE 70S.
WEDNESDAY...ANOTHER VERY HOT AND HUMID DAY WITH THE UPPER RIDGE
CENTERED OVER THE AREA. EXPECT HIGHS IN THE MID 90S AND DEWPOINTS
IN THE MID 70S. THE HEAT ADVISORY HAS BEEN EXTENDED THROUGH 7 PM
THURSDAY FOR MOST OF THE MIDSOUTH FOR HEAT INDICES EXCEEDING 105
DEGREES WEDNESDAY AFTERNOON. AN ISOLATED AFTERNOON STORM COULD
OCCUR ANYWHERE BUT THE BEST CHANCE WILL PROBABLY BE ACROSS NORTH
MISSISSIPPI.
THURSDAY...THE UPPER RIDGE WEAKENS A BIT ON THURSDAY BUT STILL
HOT AND HUMID. HEAT ADVISORIES MAY NEED TO BE EXTENDED. STILL VERY
WARM AIRMASS ACROSS THE REGION WITH 925MB TEMPS OF 28C ACROSS MUCH
OF THE AREA. MODELS ARE POINTING TOWARD INCREASING MOISTURE MOVING
UP FROM THE GULF WITH BETTER CHANCES OF AFTERNOON SHOWERS AND
THUNDERSTORMS ACROSS NORTH MISSISSIPPI.
FRIDAY AND SATURDAY...MAJOR PATTERN SHIFT AS THE UPPER RIDGE
BREAKS DOWN AND A DEEP UPPER TROF DEVELOPS OVER THE EASTERN U.S.
A COLD FRONT WILL PUSH THROUGH THE AREA FRIDAY INTO SATURDAY
MORNING WITH NUMEROUS SHOWERS AND THUNDERSTORMS. A FEW STRONG TO
SEVERE STORMS ARE POSSIBLE DURING THIS PERIOD. MUCH COOLER AND
DRIER WEATHER WILL SETTLE OVER THE REGION LATER SATURDAY INTO
EARLY NEXT WEEK AS THE REGION REMAINS UNDER THE INFLUENCE OF THE
UNSEASONABLE DEEP UPPER TROF.
SJM
&&
.AVIATION...00Z TAF CYCLE
VFR CONDITIONS EXPECTED TO PERSIST THROUGH MUCH OF THE PERIOD.
ISOLATED/SCATTERED SHOWERS AND THUNDERSTORMS MAY HAVE THE
POTENTIAL TO PRODUCE VCTS AT MKL/JBR AND PERHAPS MEM EARLY THIS
EVENING AND AT TUP WEDNESDAY AFTERNOON. LIGHT W/NW WINDS WILL VEER
N ON WEDNESDAY.
CJC
&&
.MEG WATCHES/WARNINGS/ADVISORIES...
AR...HEAT ADVISORY UNTIL 7 PM CDT WEDNESDAY FOR CLAY-CRAIGHEAD-
CRITTENDEN-CROSS-GREENE-LAWRENCE-LEE AR-MISSISSIPPI-
PHILLIPS-POINSETT-RANDOLPH-ST. FRANCIS.
MO...HEAT ADVISORY UNTIL 7 PM CDT WEDNESDAY FOR DUNKLIN-PEMISCOT.
MS...HEAT ADVISORY UNTIL 7 PM CDT WEDNESDAY FOR ALCORN-BENTON MS-
CALHOUN-CHICKASAW-COAHOMA-DESOTO-ITAWAMBA-LAFAYETTE-LEE MS-
MARSHALL-MONROE-PANOLA-PONTOTOC-PRENTISS-QUITMAN-
TALLAHATCHIE-TATE-TIPPAH-TISHOMINGO-TUNICA-UNION-YALOBUSHA.
TN...HEAT ADVISORY UNTIL 7 PM CDT WEDNESDAY FOR CHESTER-CROCKETT-DYER-
FAYETTE-HARDEMAN-HARDIN-HAYWOOD-LAKE-LAUDERDALE-MADISON-
MCNAIRY-OBION-SHELBY-TIPTON.
&&
$$
AREA FORECAST DISCUSSION
NWS MEMPHIS TN
623 PM CDT TUE JUN 23 2015
.UPDATE...
UPDATED TO ADD 00Z AVIATION DISCUSSION.
&&
.PREV DISCUSSION... /ISSUED 333 PM CDT TUE JUN 23 2015/
DISCUSSION...
CURRENTLY...STRONG UPPER RIDGE EXTENDS FROM THE SOUTHERN PLAINS
INTO THE MIDSOUTH. MEANWHILE A WEAK COLD FRONT HAS PUSHED INTO
SOUTHERN MISSOURI AND WESTERN KY...JUST NORTH OF THE MIDSOUTH.
VERY WARM AIR HAS PUSHED INTO THE MIDSOUTH WITH TEMPS IN THE MID
90S ACROSS MUCH OF THE AREA. SURFACE DEWPOINTS ARE POOLING ACROSS
THE REGION...SOUTH OF THE COLD FRONT...WITH READINGS IN THE MID
TO SOMETIMES UPPER 70S. THIS IS CREATING HEAT INDEX VALUES ABOVE
105 ACROSS MUCH OF THE MIDSOUTH. HAVE EXPANDED THE HEAT ADVISORY
TO COVER MOST OF THE MIDSOUTH THIS AFTERNOON INTO WEDNESDAY.
THE HRRR HAS BEEN TRYING TO DEVELOP CONVECTION ALONG THE WEAK COLD
FRONT TO THE NORTH FOR THE LAST FEW HOURS BUT IT HAS NOT HAPPENED
YET. GIVEN THE WEAK CAP AND SBCAPES AROUND 5000 J/KG THERE IS
STILL THE POSSIBILITY OF ISOLATED STORMS DEVELOPING OVER THE NEXT
FEW HOURS.
TONIGHT...ANY CONVECTION WILL DISSIPATE BY 02Z OR SO WITH MOSTLY
CLEAR SKIES AND WARM TEMPERATURES OVERNIGHT. LOWS IN THE 70S.
WEDNESDAY...ANOTHER VERY HOT AND HUMID DAY WITH THE UPPER RIDGE
CENTERED OVER THE AREA. EXPECT HIGHS IN THE MID 90S AND DEWPOINTS
IN THE MID 70S. THE HEAT ADVISORY HAS BEEN EXTENDED THROUGH 7 PM
THURSDAY FOR MOST OF THE MIDSOUTH FOR HEAT INDICES EXCEEDING 105
DEGREES WEDNESDAY AFTERNOON. AN ISOLATED AFTERNOON STORM COULD
OCCUR ANYWHERE BUT THE BEST CHANCE WILL PROBABLY BE ACROSS NORTH
MISSISSIPPI.
THURSDAY...THE UPPER RIDGE WEAKENS A BIT ON THURSDAY BUT STILL
HOT AND HUMID. HEAT ADVISORIES MAY NEED TO BE EXTENDED. STILL VERY
WARM AIRMASS ACROSS THE REGION WITH 925MB TEMPS OF 28C ACROSS MUCH
OF THE AREA. MODELS ARE POINTING TOWARD INCREASING MOISTURE MOVING
UP FROM THE GULF WITH BETTER CHANCES OF AFTERNOON SHOWERS AND
THUNDERSTORMS ACROSS NORTH MISSISSIPPI.
FRIDAY AND SATURDAY...MAJOR PATTERN SHIFT AS THE UPPER RIDGE
BREAKS DOWN AND A DEEP UPPER TROF DEVELOPS OVER THE EASTERN U.S.
A COLD FRONT WILL PUSH THROUGH THE AREA FRIDAY INTO SATURDAY
MORNING WITH NUMEROUS SHOWERS AND THUNDERSTORMS. A FEW STRONG TO
SEVERE STORMS ARE POSSIBLE DURING THIS PERIOD. MUCH COOLER AND
DRIER WEATHER WILL SETTLE OVER THE REGION LATER SATURDAY INTO
EARLY NEXT WEEK AS THE REGION REMAINS UNDER THE INFLUENCE OF THE
UNSEASONABLE DEEP UPPER TROF.
SJM
&&
.AVIATION...
00Z TAF CYCLE
VFR CONDITIONS EXPECTED TO PERSIST THROUGH MUCH OF THE PERIOD.
ISOLATED/SCATTERED SHOWERS AND THUNDERSTORMS MAY HAVE THE
POTENTIAL TO PRODUCE VCTS AT MKL/JBR AND PERHAPS MEM EARLY THIS
EVENING AND AT TUP WEDNESDAY AFTERNOON. LIGHT W/NW WINDS WILL VEER
N ON WEDNESDAY.
CJC
&&
.MEG WATCHES/WARNINGS/ADVISORIES...
AR...HEAT ADVISORY UNTIL 7 PM CDT WEDNESDAY FOR CLAY-CRAIGHEAD-
CRITTENDEN-CROSS-GREENE-LAWRENCE-LEE AR-MISSISSIPPI-
PHILLIPS-POINSETT-RANDOLPH-ST. FRANCIS.
MO...HEAT ADVISORY UNTIL 7 PM CDT WEDNESDAY FOR DUNKLIN-PEMISCOT.
MS...HEAT ADVISORY UNTIL 7 PM CDT WEDNESDAY FOR ALCORN-BENTON MS-
CALHOUN-CHICKASAW-COAHOMA-DESOTO-ITAWAMBA-LAFAYETTE-LEE MS-
MARSHALL-MONROE-PANOLA-PONTOTOC-PRENTISS-QUITMAN-
TALLAHATCHIE-TATE-TIPPAH-TISHOMINGO-TUNICA-UNION-YALOBUSHA.
TN...HEAT ADVISORY UNTIL 7 PM CDT WEDNESDAY FOR CHESTER-CROCKETT-DYER-
FAYETTE-HARDEMAN-HARDIN-HAYWOOD-LAKE-LAUDERDALE-MADISON-
MCNAIRY-OBION-SHELBY-TIPTON.
&&
$$
AREA FORECAST DISCUSSION
NWS MEMPHIS TN
318 PM CDT MON JUN 22 2015
.DISCUSSION...
CURRENTLY...A STRONG UPPER RIDGE CONTINUES TO BUILD EAST FROM THE
SOUTHERN PLAINS. MOISTURE HAS POOLED ACROSS THE MIDSOUTH TODAY
WITH PRECIP H20 VALUES APPROACHING 2 INCHES AND SURFACE DEWPOINTS
IN THE MID 70S. THIS DEEPER MOISTURE COMBINED WITH A WEAK
DISTURBANCE MOVING AROUND THE WESTERN EDGE OF THE UPPER RIDGE HAS
TOUCHED OFF AN AREA OF THUNDERSTORMS ACROSS PARTS OF WEST
TENNESSEE AND NORTHEAST MISSISSIPPI. THE HRRR DID AN EXCELLENT
JOB WITH COMPLEX. TO THE WEST OF THE THUNDERSTORMS THE HEAT AND
HUMIDITY IS BUILDING. HEAT INDEX VALUES HAVE REACHED 105 AT
JONESBORO AND WEST MEMPHIS.
TONIGHT...THUNDERSTORMS ACROSS EASTERN SECTIONS WILL PUSH EAST
AND DISSIPATE BY EARLY THIS EVENING LEAVING BEHIND MOSTLY CLEAR
SKIES. TEMPS WILL BE MILD WITH LOWS IN THE 70S.
TUESDAY THROUGH THURSDAY...THE STRONG UPPER RIDGE WILL CONTINUE
TO BUILD OVER THE AREA ON TUESDAY. BY WEDNESDAY IT WILL BE
CENTERED DIRECTLY OVER THE AREA THEN START TO GRADUALLY WEAKEN ON
THURSDAY. THIS WILL BE A HOT AND HUMID PERIOD. THOUGH ISOLATED
SHOWERS AND THUNDERSTORMS CANNOT BE RULED OUT TUESDAY AND
WEDNESDAY COVERAGE SHOULD BE MINIMAL. HIGHS ON TUESDAY WILL PUSH
INTO THE MID 90S WHICH WHEN COMBINED WITH HIGH HUMIDITY WILL
CREATE HEAT INDEX VALUES GREATER THAN 105 ACROSS MUCH OF THE MS
DELTA INCLUDING THE MEMPHIS METRO AREA. A HEAT ADVISORY CONTINUES
THROUGH 7 PM TUESDAY FOR THE AFOREMENTIONED AREA. BY WEDNESDAY
TEMPS MAY HIT THE UPPER 90S IN A FEW SPOTS AND THE HEAT ADVISORY
WILL PROBABLY NEED TO BE EXPANDED. BY THURSDAY THE UPPER RIDGE
WEAKENS SLIGHTLY AND SOME DEEPER MOISTURE MOVES IN FROM THE SOUTH
WHICH WILL RESULT IN BETTER SHOWER/THUNDERSTORM COVERAGE...ESPECIALLY
ACROSS NORTH MISSISSIPPI. IT WILL STILL BE QUITE HOT WITH HIGHS IN
THE MID 90S IN SOME PLACES SO HEAT ADVISORIES MAY BE NEEDED ON
THURSDAY AS WELL.
FRIDAY INTO THE WEEKEND...MEDIUM RANGE MODELS ARE IN GOOD
AGREEMENT WITH BREAKING DOWN THE UPPER RIDGE AS A DEEP UPPER TROF
DEVELOPS OVER THE EASTERN U.S. A COLD FRONT WILL PUSH THROUGH THE
MIDSOUTH FRIDAY AND SATURDAY WITH NUMEROUS SHOWERS AND
THUNDERSTORMS. RAIN CHANCES WILL DIMINISH LATER SATURDAY AND
SUNDAY. MUCH COOLER AIR WILL PUSH INTO THE AREA FOR THE WEEKEND
WITH HIGHS IN THE 80S AND LOWS IN THE 60S.
SJM
&&
.AVIATION...
18Z TAF CYCLE
VFR CONDITIONS WILL PERSIST THROUGH THE ENTIRE FORECAST PERIOD.
THUNDERSTORMS WILL BE POSSIBLE THROUGH THE AFTERNOON AND EVENING
HOURS...THUS A VCTS HAS BEEN INCLUDED FOR ALL SITES THROUGH AROUND
00Z. GUSTY WINDS THIS AFTERNOON WILL SUBSIDE TO BE LESS THAN 8
KTS OVERNIGHT.
ZDM
&&
.MEG WATCHES/WARNINGS/ADVISORIES...
AR...HEAT ADVISORY UNTIL 7 PM CDT TUESDAY FOR CRAIGHEAD-CRITTENDEN-
CROSS-LEE AR-MISSISSIPPI-PHILLIPS-POINSETT-ST. FRANCIS.
MO...NONE.
MS...HEAT ADVISORY UNTIL 7 PM CDT TUESDAY FOR COAHOMA-DESOTO-PANOLA-
QUITMAN-TALLAHATCHIE-TATE-TUNICA.
TN...HEAT ADVISORY UNTIL 7 PM CDT TUESDAY FOR SHELBY-TIPTON.
&&
$$
AREA FORECAST DISCUSSION
NWS MEMPHIS TN
1243 PM CDT MON JUN 22 2015
.UPDATE...
UPDATED TO INCLUDE 18Z AVIATION DISCUSSION.
&&
.PREV DISCUSSION... /ISSUED 1048 AM CDT MON JUN 22 2015/
DISCUSSION...
UPPER LEVEL RIDGE CONTINUES TO EXPAND EASTWARD OVER THE MIDSOUTH.
SUNSHINE IS MORE PREVALENT TODAY AS THE MID AND HIGH CLOUDS OVER
NORTH MS CONTINUE TO BREAK. TEMPS ARE RUNNING A LITTLE WARMER THAN
YESTERDAY. THE WARMER TEMPS COMBINED WITH VERY HIGH DEWPOINTS IN
THE MID 70S AND HEAT INDEX VALUES ARE APPROACHING 100 DEGREES IN
SOME AREAS. EXPECTING HIGHS IN THE LOWER TO MID 90S. HEAT ADVISORY
IN EFFECT FOR MUCH OF THE MS DELTA INCLUDING MEMPHIS THROUGH
TUESDAY.
QUESTION FOR THIS AFTERNOON CONCERNS CONVECTIVE DEVELOPMENT.
LATEST HRRR/RAP DOES INITIATE A FAIR AMOUNT OF CONVECTION ACROSS
PARTS OF THE MIDSOUTH BY NOON TODAY...CONTINUING THROUGH THE AFTN
HOURS. LOW LEVEL MOISTURE HAS INCREASED QUITE A BIT FROM
YESTERDAY. 12Z PRECIP H20 AT KLZK HAS INCREASED FROM 1.37 INCHES
TO 1.81 INCHES OVER THE PAST 24 HOURS. KINDEX VALUES ARE GREATER
THAN 30 ACROSS THE AREA. SURFACE HEATING WILL CREATE LARGE CAPE
VALUES THOUGH MID LEVEL LAPSE RATES ARE POOR. THE UPPER RIDGE IS
ALSO NOT STRONG ENOUGH TO PRODUCE A SIGNIFICANT CAP YET. STRONGER
LOW LEVEL FLOW EXISTS ACROSS WESTERN ARKANSAS AND PERHAPS THIS
WILL CREATE ENOUGH LIFT TO HELP INITIATE STORMS OVER EASTERN
ARKANSAS LIKE THE 14Z HRRR INDICATES. FOR NOW WILL ADD A SMALL
POP ACROSS THE MIDSOUTH AND MENTION A STRONG STORM IN THE HWO.
SJM
PREV DISCUSSION... /ISSUED 416 AM CDT MON JUN 22 2015/
EXCESSIVE HEAT IS THE MAIN STORY THROUGH MID-WEEK...THEN A COLD
FRONT WILL APPROACH AND MOVE THROUGH THE AREA FRIDAY AND SATURDAY
CAUSING NUMEROUS SHOWERS AND THUNDERSTORMS.
TRANQUIL WEATHER WAS OCCURRING ACROSS THE MIDSOUTH EARLY THIS
MORNING. TEMPERATURES WERE IN THE 70S WITH A BAND OF MIDDLE AND
HIGH LEVEL CLOUDS STRETCHING FROM EAST CENTRAL AR ACROSS NORTH MS
INTO SOUTHWEST TN.
BEGINNING AT NOON TODAY...EXPANDED THE HEAT ADVISORY TO INCLUDE
MUCH OF NORTHEAST AND EAST CENTRAL AR...PORTIONS OF SOUTHWEST TN
AND NORTHWEST MS. THIS INCLUDE THE CITIES OF JONESBORO AND
MEMPHIS. HEAT INDEX READING ARE FORECAST TO CLIMB TO AROUND 105
DEGREES IN THIS AREA THIS AFTERNOON. SOUTHWEST WINDS WILL
FEED HOTTER AIR INTO THE REGION AS A STRONG UPPER LEVEL RIDGE
CENTERED OVER THE SOUTHWESTERN UNITED STATES EXPANDS EASTWARD.
THERE IS A WEAKNESS ACROSS THE MIDSOUTH BETWEEN THIS RIDGE AND
AND UPPER HIGH CENTERED OFF THE ATLANTIC COAST. MODELS ARE
INDICATING A SLIGHT CHANCE OF SHOWERS AND THUNDERSTORMS TODAY
ALONG AND AHEAD OF THIS WEAKNESS AS IT MOVES TO THE EAST. INCLUDED
20 PERCENT POPS ALONG AND SOUTHEAST OF INTERSTATE 40.
THE WESTERN UPPER LEVEL RIDGE WILL CONTINUE TO BUILD ACROSS THE
MIDSOUTH TUESDAY AND REMAIN OVER THE AREA INTO WEDNESDAY. H5
HEIGHTS WILL INCREASE TO 596 DM ACROSS THE MIDSOUTH. LITTLE IF ANY
RAIN IS EXPECTED TUESDAY...AND INCLUDED JUST A 20 PERCENT CHANCE
OF AFTERNOON AND EVENING SHOWERS AND THUNDERSTORMS WEDNESDAY FOR
NORTHEAST MS. CONTINUED THE HEAT ADVISORY THROUGH TUESDAY FOR THE
SAME AS AREA AS TODAY...BUT LATER FORECASTS MAY NEED TO EXPAND THE
ADVISORY TO INCLUDE MORE OF THE MIDSOUTH TUESDAY. IN
ADDITION...THE HEAT ADVISORY WILL PROBABLY NEED TO BE EXTENDED
INTO WEDNESDAY FOR MUCH OF THE MIDSOUTH.
THE UPPER LEVEL RIDGE OVER THE MIDSOUTH IS FORECAST TO BEGIN TO
WEAKEN THURSDAY WITH MOISTURE INCREASING FROM THE SOUTH. A SLIGHT
CHANCE TO CHANCE OF SHOWERS AND THUNDERSTORMS IS FORECAST FOR
MUCH OF THE REGION.
THE ECMWF AND GFS ARE IN GOOD AGREEMENT IN A SIGNIFICANT CHANGE IN
THE WEATHER PATTERN THAT WILL TAKE PLACE LATE IN THE WORK WEEK AND
OVER THE WEEKEND. BY FRIDAY...THE UPPER LEVEL RIDGE OVER THE
MIDSOUTH IS FORECAST TO COLLAPSE WITH THE REGION FIRMLY IN
NORTHWEST FLOW ALOFT. AN UNSEASONABLY STRONG UPPER LEVEL TROUGH
FOR THIS TIME OF THE YEAR IS FORECAST TO EVOLVE ALONG THE EASTERN
UNITED STATES. A COLD FRONT IS FORECAST TO APPROACH THE MIDSOUTH
FROM THE NORTH FRIDAY AND MOVE THROUGH THE REGION SATURDAY.
UNSTABLE AND MOIST AIR AHEAD OF THE COLD FRONT WILL RESULT IN A
CHANCE OF SEVERE THUNDERSTORMS. ALSO...PRECIPITABLE WATER VALUES
WILL CLIMB TO ABOVE 2 INCHES AHEAD OF THE FRONT LEADING TO LOCALLY
HEAVY RAINFALL. SINCE THE MODELS ARE IN GOOD AGREEMENT...WENT
AHEAD AND MENTIONED THESE THREATS IN THE HAZARDOUS WEATHER
OUTLOOK.
JCL
&&
.AVIATION...
18Z TAF CYCLE
VFR CONDITIONS WILL PERSIST THROUGH THE ENTIRE FORECAST PERIOD.
THUNDERSTORMS WILL BE POSSIBLE THROUGH THE AFTERNOON AND EVENING
HOURS...THUS A VCTS HAS BEEN INCLUDED FOR ALL SITES THROUGH AROUND
00Z. GUSTY WINDS THIS AFTERNOON WILL SUBSIDE TO BE LESS THAN 8
KTS OVERNIGHT.
ZDM
&&
.MEG WATCHES/WARNINGS/ADVISORIES...
AR...HEAT ADVISORY UNTIL 7 PM CDT TUESDAY FOR CRAIGHEAD-CRITTENDEN-
CROSS-LEE AR-MISSISSIPPI-PHILLIPS-POINSETT-ST. FRANCIS.
MO...NONE.
MS...HEAT ADVISORY UNTIL 7 PM CDT TUESDAY FOR COAHOMA-DESOTO-PANOLA-
QUITMAN-TALLAHATCHIE-TATE-TUNICA.
TN...HEAT ADVISORY UNTIL 7 PM CDT TUESDAY FOR SHELBY-TIPTON.
&&
$$
AREA FORECAST DISCUSSION
NWS MEMPHIS TN
1048 AM CDT MON JUN 22 2015
.DISCUSSION...
UPPER LEVEL RIDGE CONTINUES TO EXPAND EASTWARD OVER THE MIDSOUTH.
SUNSHINE IS MORE PREVALENT TODAY AS THE MID AND HIGH CLOUDS OVER
NORTH MS CONTINUE TO BREAK. TEMPS ARE RUNNING A LITTLE WARMER THAN
YESTERDAY. THE WARMER TEMPS COMBINED WITH VERY HIGH DEWPOINTS IN
THE MID 70S AND HEAT INDEX VALUES ARE APPROACHING 100 DEGREES IN
SOME AREAS. EXPECTING HIGHS IN THE LOWER TO MID 90S. HEAT ADVISORY
IN EFFECT FOR MUCH OF THE MS DELTA INCLUDING MEMPHIS THROUGH
TUESDAY.
QUESTION FOR THIS AFTERNOON CONCERNS CONVECTIVE DEVELOPMENT.
LATEST HRRR/RAP DOES INITIATE A FAIR AMOUNT OF CONVECTION ACROSS
PARTS OF THE MIDSOUTH BY NOON TODAY...CONTINUING THROUGH THE AFTN
HOURS. LOW LEVEL MOISTURE HAS INCREASED QUITE A BIT FROM
YESTERDAY. 12Z PRECIP H20 AT KLZK HAS INCREASED FROM 1.37 INCHES
TO 1.81 INCHES OVER THE PAST 24 HOURS. KINDEX VALUES ARE GREATER
THAN 30 ACROSS THE AREA. SURFACE HEATING WILL CREATE LARGE CAPE
VALUES THOUGH MID LEVEL LAPSE RATES ARE POOR. THE UPPER RIDGE IS
ALSO NOT STRONG ENOUGH TO PRODUCE A SIGNIFICANT CAP YET. STRONGER
LOW LEVEL FLOW EXISTS ACROSS WESTERN ARKANSAS AND PERHAPS THIS
WILL CREATE ENOUGH LIFT TO HELP INITIATE STORMS OVER EASTERN
ARKANSAS LIKE THE 14Z HRRR INDICATES. FOR NOW WILL ADD A SMALL
POP ACROSS THE MIDSOUTH AND MENTION A STRONG STORM IN THE HWO.
SJM
&&
PREV DISCUSSION... /ISSUED 416 AM CDT MON JUN 22 2015/
EXCESSIVE HEAT IS THE MAIN STORY THROUGH MID-WEEK...THEN A COLD
FRONT WILL APPROACH AND MOVE THROUGH THE AREA FRIDAY AND SATURDAY
CAUSING NUMEROUS SHOWERS AND THUNDERSTORMS.
TRANQUIL WEATHER WAS OCCURRING ACROSS THE MIDSOUTH EARLY THIS
MORNING. TEMPERATURES WERE IN THE 70S WITH A BAND OF MIDDLE AND
HIGH LEVEL CLOUDS STRETCHING FROM EAST CENTRAL AR ACROSS NORTH MS
INTO SOUTHWEST TN.
BEGINNING AT NOON TODAY...EXPANDED THE HEAT ADVISORY TO INCLUDE
MUCH OF NORTHEAST AND EAST CENTRAL AR...PORTIONS OF SOUTHWEST TN
AND NORTHWEST MS. THIS INCLUDE THE CITIES OF JONESBORO AND
MEMPHIS. HEAT INDEX READING ARE FORECAST TO CLIMB TO AROUND 105
DEGREES IN THIS AREA THIS AFTERNOON. SOUTHWEST WINDS WILL
FEED HOTTER AIR INTO THE REGION AS A STRONG UPPER LEVEL RIDGE
CENTERED OVER THE SOUTHWESTERN UNITED STATES EXPANDS EASTWARD.
THERE IS A WEAKNESS ACROSS THE MIDSOUTH BETWEEN THIS RIDGE AND
AND UPPER HIGH CENTERED OFF THE ATLANTIC COAST. MODELS ARE
INDICATING A SLIGHT CHANCE OF SHOWERS AND THUNDERSTORMS TODAY
ALONG AND AHEAD OF THIS WEAKNESS AS IT MOVES TO THE EAST. INCLUDED
20 PERCENT POPS ALONG AND SOUTHEAST OF INTERSTATE 40.
THE WESTERN UPPER LEVEL RIDGE WILL CONTINUE TO BUILD ACROSS THE
MIDSOUTH TUESDAY AND REMAIN OVER THE AREA INTO WEDNESDAY. H5
HEIGHTS WILL INCREASE TO 596 DM ACROSS THE MIDSOUTH. LITTLE IF ANY
RAIN IS EXPECTED TUESDAY...AND INCLUDED JUST A 20 PERCENT CHANCE
OF AFTERNOON AND EVENING SHOWERS AND THUNDERSTORMS WEDNESDAY FOR
NORTHEAST MS. CONTINUED THE HEAT ADVISORY THROUGH TUESDAY FOR THE
SAME AS AREA AS TODAY...BUT LATER FORECASTS MAY NEED TO EXPAND THE
ADVISORY TO INCLUDE MORE OF THE MIDSOUTH TUESDAY. IN
ADDITION...THE HEAT ADVISORY WILL PROBABLY NEED TO BE EXTENDED
INTO WEDNESDAY FOR MUCH OF THE MIDSOUTH.
THE UPPER LEVEL RIDGE OVER THE MIDSOUTH IS FORECAST TO BEGIN TO
WEAKEN THURSDAY WITH MOISTURE INCREASING FROM THE SOUTH. A SLIGHT
CHANCE TO CHANCE OF SHOWERS AND THUNDERSTORMS IS FORECAST FOR
MUCH OF THE REGION.
THE ECMWF AND GFS ARE IN GOOD AGREEMENT IN A SIGNIFICANT CHANGE IN
THE WEATHER PATTERN THAT WILL TAKE PLACE LATE IN THE WORK WEEK AND
OVER THE WEEKEND. BY FRIDAY...THE UPPER LEVEL RIDGE OVER THE
MIDSOUTH IS FORECAST TO COLLAPSE WITH THE REGION FIRMLY IN
NORTHWEST FLOW ALOFT. AN UNSEASONABLY STRONG UPPER LEVEL TROUGH
FOR THIS TIME OF THE YEAR IS FORECAST TO EVOLVE ALONG THE EASTERN
UNITED STATES. A COLD FRONT IS FORECAST TO APPROACH THE MIDSOUTH
FROM THE NORTH FRIDAY AND MOVE THROUGH THE REGION SATURDAY.
UNSTABLE AND MOIST AIR AHEAD OF THE COLD FRONT WILL RESULT IN A
CHANCE OF SEVERE THUNDERSTORMS. ALSO...PRECIPITABLE WATER VALUES
WILL CLIMB TO ABOVE 2 INCHES AHEAD OF THE FRONT LEADING TO LOCALLY
HEAVY RAINFALL. SINCE THE MODELS ARE IN GOOD AGREEMENT...WENT
AHEAD AND MENTIONED THESE THREATS IN THE HAZARDOUS WEATHER
OUTLOOK.
JCL
&&
.AVIATION...
12Z TAFS
VFR CONDITIONS ARE EXPECTED THROUGH THE PERIOD. WINDS WILL BECOME
A LITTLE BIT GUSTY AFTER 17Z ON MONDAY WITH GUSTS APPROACHING 20
MPH THROUGH THE AFTERNOON FROM THE WEST-SOUTHWEST. THESE WILL DIE
DOWN QUICKLY AFTER 00Z WITH LIGHT WINDS THROUGH THE OVERNIGHT
PERIOD.
TVT
&&
.MEG WATCHES/WARNINGS/ADVISORIES...
AR...HEAT ADVISORY UNTIL 7 PM CDT TUESDAY FOR CRAIGHEAD-CRITTENDEN-
CROSS-LEE AR-MISSISSIPPI-PHILLIPS-POINSETT-ST. FRANCIS.
MO...NONE.
MS...HEAT ADVISORY UNTIL 7 PM CDT TUESDAY FOR COAHOMA-DESOTO-PANOLA-
QUITMAN-TALLAHATCHIE-TATE-TUNICA.
TN...HEAT ADVISORY UNTIL 7 PM CDT TUESDAY FOR SHELBY-TIPTON.
&&
$$
AREA FORECAST DISCUSSION
NWS MEMPHIS TN
1118 PM CDT SUN JUN 21 2015
.UPDATE...AVIATION DISCUSSION.
&&
.PREV DISCUSSION... /ISSUED 919 PM CDT SUN JUN 21 2015/
DISCUSSION...WATER VAPOR SATELLITE ALONG WITH 00Z UPPER AIR
ANALYSIS INDICATES AN UPPER LEVEL RIDGE CENTERED OVER THE
SOUTHWEST UNITED STATES AND EXTENDING INTO PORTIONS OF THE CENTRAL
AND SOUTHERN PLAINS. MEANWHILE...THE LOWER MISSISSIPPI VALLEY AND
MID SOUTH REMAIN ON THE EASTERN PERIPHERY OF THIS UPPER LEVEL
RIDGE AXIS. ISOLATED SHOWERS AND THUNDERSTORMS HAVE DIMINISHED
THIS EVENING WITH THE LOSS OF DAYTIME INSTABILITY. 00Z WRF AND
LATEST HRRR INDICATE A POTENTIAL FOR ISOLATED SHOWERS AND PERHAPS
A THUNDERSTORM TO DEVELOP ACROSS THE MID SOUTH OVERNIGHT.
HOWEVER...CONFIDENCE IN OCCURRENCE AND OVERALL COVERAGE REMAINS
TOO LOW TO JUSTIFY MENTION IN OVERNIGHT FORECAST AT THIS MOMENT
BUT WILL CONTINUE TO MONITOR SHORT TERM TRENDS. WILL UPDATE
FORECAST TO REMOVE EVENING POPS ACROSS NORTH MISSISSIPPI AND TO
ADJUST ALL OTHER ELEMENTS AS NEEDED. HEAT INDEX READINGS ARE
EXPECTED TO APPROACH 105 DEGREES AROUND/AFTER 12 PM MONDAY.
UPDATED GRIDS WILL BE AVAILABLE SHORTLY.
CJC
PREV DISCUSSION... /ISSUED 625 PM CDT SUN JUN 21 2015/
UPDATE...AVIATION DISCUSSION.
PREV DISCUSSION... /ISSUED 259 PM CDT SUN JUN 21 2015/
DISCUSSION...
BLOW OFF CLOUD COVER ASSOCIATED WITH CONVECTION OVER THE RED
RIVER VALLEY HAS KEPT TEMPERATURES FROM GETTING AS WARM AS
PREVIOUSLY THOUGHT. ALTHOUGH...DEWPOINTS REMAIN IN THE MID 70S SO
IN PEAKS OF SUNSHINE...HEAT INDICES COULD STILL REACH NEAR 105
DEGREES. WILL LEAVE HEAT ADVISORY AS IS.
MEANWHILE...SPOTTY THUNDERSTORMS CONTINUE TO DEVELOP OVER THE
AREA. CAN/T RULE OUT ONE OF THEM BECOMING SEVERE PRODUCING A WET
MICROBURST. WILL KEEP 20 POPS ACROSS NORTH MISSISSIPPI THROUGH THE
EVENING HOURS.
EXPECT THE UPPER RIDGE TO BUILD IN FURTHER ON MONDAY AND TUESDAY.
LESS CLOUD COVER SHOULD BE AROUND THUS TEMPERATURES SHOULD GET
INTO THE MID TO UPPER 90S PRETTY EASILY. THE COMBINATION OF THE
HOT TEMPERATURES AND DEWPOINTS IN THE 70-75 DEGREE RANGE WILL
PRODUCE HEAT INDICES OF 105 DEGREES OR GREATER BY TUESDAY ACROSS
THE ENTIRE CWA. THE HEAT ADVISORY MAY NEED TO BE EXPANDED.
ON WEDNESDAY...MODELS ARE INDICATING THAT THE RIDGE MAY WEAKEN
SLIGHTLY OVER THE AREA THAT COULD ALLOW DIURNAL CONVECTION TO FIRE
UP. IN ADDITION...BOTH THE ECMWF AND GFS SHOW AN MCS DEVELOPING
TUESDAY NIGHT THAT MAY POSSIBLY MOVE INTO AREAS OF WEST TENNESSEE
NEAR THE TENNESSEE RIVER ON WEDNESDAY. THE CLOUDS AND CONVECTION
MAY KEEP TEMPERATURES DOWN JUST A TAD. THUS ALLOWING HEAT INDICES
TO STAY BELOW 15 DEGREES BUT WILL HAVE TO WAIT TO SEE WHAT
HAPPENS.
EACH DAY THEREAFTER...THE RIDGE GETS A LITTLE WEAKER. MODELS
ARE SHOWING MORE AND MORE CONVECTION FIRING UP ESPECIALLY IN THE
FRIDAY THROUGH SATURDAY NIGHT TIME PERIOD AS THE GFS AND ECMWF SHOW
A COLD FRONT SINKING INTO THE AREA AND AN UPPER TROF MOVING
THROUGH THE REGION.
LINGERING SHOWERS AND THUNDERSTORMS COULD OCCUR ACROSS NORTH
MISSISSIPPI ON SUNDAY BUT TEMPERATURES SHOULD FEEL MORE PLEASANT
WITH READINGS IN THE LOWER TO MID 80S.
KRM
&&
.AVIATION...06Z TAFS
VFR CONDITIONS ARE EXPECTED THROUGH THE PERIOD. W/SW WINDS AROUND
5KT OVERNIGHT INCREASING TO 10-15 TOMORROW. ISOLATED
THUNDERSTORMS ARE POSSIBLE BUT NOT NUMEROUS ENOUGH TO INCLUDE IN
TAFS.
&&
.MEG WATCHES/WARNINGS/ADVISORIES...
AR...HEAT ADVISORY FROM 10 AM TO 7 PM CDT MONDAY FOR CRITTENDEN-CROSS-
LEE AR-PHILLIPS-ST. FRANCIS.
MO...NONE.
MS...HEAT ADVISORY FROM 10 AM TO 7 PM CDT MONDAY FOR COAHOMA-DESOTO-
PANOLA-QUITMAN-TALLAHATCHIE-TATE-TUNICA.
TN...HEAT ADVISORY FROM 10 AM TO 7 PM CDT MONDAY FOR SHELBY.
&&
$$
AREA FORECAST DISCUSSION
NWS AUSTIN/SAN ANTONIO TX
217 PM CDT MON JUN 22 2015
.SHORT TERM (TONIGHT THROUGH TUESDAY NIGHT)...
THERE IS NOT MUCH RAIN ACTIVITY ONGOING ACROSS SOUTH-CENTRAL
TEXAS THIS AFTERNOON. THERE IS ONE AREA OF LIGHT TO MODERATE RAIN
REMAINING ACROSS THE EXTREME SOUTHWESTERN COUNTIES...BUT THE REST
OF THE CWA REMAINS MOSTLY DRY. PRECIPITABLE WATER VALUES CONTINUE
TO SLOWLY DECREASE AS A 700 MB RIDGE AXIS BUILDS INTO SOUTHEAST
TEXAS FROM THE EAST. SUBSIDENCE FROM THIS SYSTEM AND SLIGHTLY
DRIER AIR IS KEEPING THE COVERAGE OF ACTIVITY MUCH LESS THAN
PREVIOUS DAYS. THE HRRR IS STILL FORECASTING SOME ISOLATED
CONVECTION LATER THIS AFTERNOON AND WILL KEEP 20 POPS IN THE
FORECAST FOR THE EVENING FOR MUCH OF THE AREA. AN UPPER LOW
REMAINS JUST WEST OF THE CWA AND WILL HAVE 30 POPS THIS EVENING
CLOSER TO THE RIO GRANDE TO ACCOUNT FOR BETTER LIFT IN THIS PART
OF THE CWA.
FOR TOMORROW...THE 700 MB RIDGE AXIS WILL REMAIN TO OUR EAST WITH
THE UPPER LOW TO OUR WEST WEAKENING AND BEGINNING TO SHIFT WEST.
MOISTURE VALUES WILL BE HIGH ENOUGH TO WARRANT 20 POPS FOR MUCH OF
THE CWA FOR ANY CONVECTION THAT DEVELOPS IN THE WEAK SOUTHEAST
FLOW. TEMPERATURES TOMORROW AFTERNOON WILL ONLY REACH THE UPPER
80S TO NEAR 90 DEGREES. HOWEVER...DEWPOINTS ARE NOT EXPECTED TO
MIX OUT AND WILL REMAIN IN THE LOWER 70S. HEAT INDICES TOMORROW
AFTERNOON MAY BE AS HIGH AS THE UPPER 90S.
&&
.LONG TERM (WEDNESDAY THROUGH MONDAY)...
WEDNESDAY/THURSDAY WILL BE A SIMILAR SETUP TO TUESDAY...BUT OUR
WESTERN UPPER LOW WILL BE A NON-PLAYER WEATHER WISE. THE GULF OF
MEXICO WILL REMAIN OPENED UP WITH SOUTHEAST FLOW AND AFTERNOON
CONVECTION WILL REMAIN POSSIBLE MAINLY ACROSS THE SOUTHERN
AND SOUTHEASTERN COUNTIES. THE UPPER RIDGE WILL STRENGTHEN OVER
THE AREA FRIDAY AND THE REGION SHOULD REMAIN MOSTLY DRY.
BY LATE SATURDAY AND INTO SUNDAY...THE UPPER PATTERN WILL BE
SHIFTING. A STRONG RIDGE WILL AMPLIFY ACROSS THE WESTERN CONUS
WITH A DEEP TROUGH OVER THE EASTERN CONUS. THIS PLACES THE CENTRAL
PLAINS IN NORTHWEST FLOW BETWEEN THE SYSTEMS. MODELS ARE SHOWING A
WEAK FRONTAL BOUNDARY NEARING THE CWA SATURDAY NIGHT AND SUNDAY
AND WILL INCREASE POPS TO ACCOUNT FOR THIS FEATURE. WILL HAVE TO
WATCH FOR POSSIBLE LOCALLY HEAVY RAINFALL GIVEN THERE WILL BE A
BOUNDARY PRESENT AND DECENT MOISTURE. IT IS TOO EARLY TO GET INTO
SPECIFICS BECAUSE OF MANY UNKNOWNS ON THE MESOSCALE BUT IT IS
SOMETHING TO WATCH.
&&
.PRELIMINARY POINT TEMPS/POPS...
AUSTIN CAMP MABRY 73 90 73 90 74 / 10 20 10 20 10
AUSTIN BERGSTROM INTL AIRPORT 72 90 72 90 73 / 10 20 10 20 10
NEW BRAUNFELS MUNI AIRPORT 73 89 73 89 74 / 20 20 10 20 10
BURNET MUNI AIRPORT 72 89 72 88 73 / 10 10 10 10 10
DEL RIO INTL AIRPORT 73 89 74 89 75 / 30 20 20 20 10
GEORGETOWN MUNI AIRPORT 72 89 73 89 74 / 10 10 10 10 10
HONDO MUNI AIRPORT 73 88 73 88 74 / 20 20 10 20 10
SAN MARCOS MUNI AIRPORT 73 89 73 89 74 / 10 20 10 20 10
LA GRANGE - FAYETTE REGIONAL 74 90 74 89 75 / - 20 10 30 10
SAN ANTONIO INTL AIRPORT 74 89 74 88 75 / 20 20 10 20 10
STINSON MUNI AIRPORT 75 89 74 89 75 / 20 20 10 20 10
&&
.EWX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
MESOSCALE/AVIATION...ALLEN
SYNOPTIC/GRIDS...HAMPSHIRE
PUBLIC SERVICE/DATA COLLECTION...30
AREA FORECAST DISCUSSION...UPDATED
NWS AUSTIN/SAN ANTONIO TX
1257 PM CDT MON JUN 22 2015
.AVIATION.../18Z TAF CYCLE/
MIXTURE OF MVFR (KSAT/KSSF) AND VFR (KDRT/KAUS) CONDITIONS ONGOING
THROUGH EARLY AFTERNOON AS LOWER STRATUS AND SHRA LINGER ACROSS
THE REGION. KSAT/KSSF SHOULD SLOWLY IMPROVE THROUGH THE MID/LATE
AFTN HOURS OVERALL BUT PERIODIC SHOWER GENERATION SHOULD MOVE OVER
THOSE TERMINALS 20-00Z. THESE SHOWERS AND SOME POSSIBLE ISOLATED
TSRA ACTIVITY COULD REDUCE OBS BACK TO MVFR FOR LOWER CIGS AND
REDUCED VIS. KAUS COULD ALSO RECEIVE SOME SHRA THIS AFTN INTO
EARLY EVENING AS WELL WITH VCSH PLACED IN TAF FOR NOW. KDRT WILL
ALSO HAVE SHRA AND SOME TSRA POSSIBILITIES THROUGH THE AFTN AND
EARLY EVENING. ALL SITES WILL FALL TO MVFR AND THEN IFR OVERNIGHT.
SOME LIFR CONDITIONS COULD BE POSSIBLE FOR KSAT/KSSF WITH CIGS
LOWER THAN 500 FT 10-14Z. SOME DZ IS QUITE POSSIBLE OVERNIGHT AS
WELL GIVEN THE SATURATED LOWER ATMOSPHERE. A VERY SLOW IMPROVEMENT
IS EXPECTED TUESDAY AS A WEATHER DISTURBANCE OVER THE RIO GRANDE
VALLEY REMAINS NEAR THE REGION. SURFACE WINDS WILL BE NEAR 10 KT
OR LESS FROM THE SOUTH THROUGH THE PERIOD. SOME HIGHER GUSTS COULD
BE POSSIBLE NEAR ORGANIZED TSRA OR OUTFLOW BOUNDARIES.
&&
.PREV DISCUSSION... /ISSUED 941 AM CDT MON JUN 22 2015/
UPDATE...
SCATTERED AREAS OF MOSTLY LIGHT RAIN CONTINUE ACROSS SOUTH CENTRAL
TEXAS WITH ONE MODERATE NARROW BAND OF RAIN ACROSS MAVERICK AND
KINNEY COUNTIES. PRECIPITABLE WATER VALUES ARE A BIT LESS THAN
YESTERDAY AS SLIGHTLY DRIER AIR MOVES IN FROM THE WEST AS A 700 MB
RIDGE AXIS SLOWLY BUILDS INTO SOUTHEAST TEXAS. THERE WILL BE
ENOUGH HEATING AND MOISTURE FOR AFTERNOON CONVECTION...ESPECIALLY
WITH AN UPPER DISTURBANCE REMAINING TO OUR WEST...BUT RAIN RATES
SHOULD BE A BIT LESS AND PROBABLY NOT THE SAME AMOUNT OF COVERAGE
AS THE PREVIOUS COUPLE OF DAYS. RAINFALL AMOUNTS WILL AVERAGE LESS
THAN AN INCH BUT 1-2 INCHES WILL BE POSSIBLE FROM THE HEAVIEST
STORMS.
PREV DISCUSSION... /ISSUED 609 AM CDT MON JUN 22 2015/
AVIATION DISCUSSION...FOR 12Z TAF PACKAGE...
TSRA CURRENTLY OBSERVED ON RADAR AND SATELLITE IS MOVING NORTHWEST
AWAY FROM THE KSAT/KSSF TERMINALS. ADDITIONAL DEVELOPMENT THIS
MORNING WILL BE POSSIBLE SO INCLUDED VCTS IN THE MID MORNING
TIME FRAME AND PERSISTING THROUGH THE AFTERNOON. THE ISOLATED
NATURE OF THESE STORMS MAKE IT DIFFICULT TO HONE IN ON A
PREVAILING LINE.
CIG AND VIS IMPROVEMENT IS EXPECTED TO MVFR BY MID MORNING AS PER
PREVIOUS MORNINGS WITH A 4-5 KFT DECK IN PLACE MUCH OF THE DAY FOR
ALL TERMINALS. IFR CIGS ARE EXPECTED TO RETURN OVERNIGHT
TONIGHT...ESPECIALLY AT THE KSAT/KSSF TERMINALS.
PREV DISCUSSION... /ISSUED 324 AM CDT MON JUN 22 2015/
SHORT TERM (TODAY THROUGH TUESDAY)...MODELS HAVE HAD A HARD TIME
WITH THE EVOLUTION OF THE MID LEVEL CYCLONIC CIRCULATION ACROSS
MEXICO AND ASSOCIATED TROUGH AXIS EXTENDING THROUGH THE WESTERN
CWA. THE MID LEVEL LOW ACROSS MEXICO APPEARS TO BE CLOSER TO THE
RIO GRANDE THAN MODELS INDICATED YESTERDAY...LOCATED SOUTH OF
EAGLE PASS AND NORTHWEST OF LAREDO. A SLIGHT DRIFT NORTH OR
NORTHWEST IS EXPECTED TODAY BEFORE EVENTUALLY OPENING AND MOVING
WEST TUESDAY. DUE TO THE CLOSER PROXIMITY OF THE LOW AND SLOWER
EVOLUTION TO THE WEST...DRYING HAS BEEN DELAYED AND MID LEVEL
FORCING CONTINUES.
A SLIGHT DOWNWARD TREND IN ONGOING SHOWER ACTIVITY ACROSS THE
WESTERN CWA MAY TAKE PLACE THIS MORNING. THEN DE-STABILIZATION
THIS AFTERNOON COMBINED WITH MID LEVEL ASCENT ACROSS THE CENTRAL
AND WESTERN CWA SHOULD RESULT IN A SIMILAR REPEAT TO CONVECTION
FROM YESTERDAY. HRRR AGAIN DEPICTS THE I-35 CORRIDOR WITH QPF THIS
AFTERNOON AS WELL AS THE 00Z ECMWF...WHILE GFS AND NAM12 ARE MORE
ACROSS THE WINTER GARDEN AND WESTERN HILL COUNTRY REGION.
SCATTERED POPS HAVE BEEN INDICATED NEAR THE I-35 CORRIDOR COUNTIES
AND WESTWARD FOR THIS AFTERNOON...AND ACROSS THE WESTERN CWA
TONIGHT. SOME STORMS COULD PRODUCE QUICK...HEAVY DOWNPOURS TODAY
ALONG WITH SOME STRONGER WIND GUSTS...SIMILAR TO YESTERDAY.
ASSUMING THE MID LEVEL LOW DOES MOVE WEST AND OPEN TUESDAY...THERE
SHOULD BE A DOWNWARD TREND IN THE POPS ON TUESDAY...WITH MAINLY
ISOLATED COVERAGE...EXPECT CLOSE TO THE RIO GRANDE WHERE BETTER
MOISTURE POOLING AND WEAK FORCING MAY CONTINUE HIGHER COVERAGE.
CONTINUED BELOW NORMAL HIGH TEMPS FOR TODAY AND TUESDAY.
LONG TERM (TUESDAY NIGHT THROUGH SUNDAY)...POPS WEDNESDAY AND
THURSDAY WILL BE CONFINED MAINLY ACROSS SOUTHERN AND EASTERN
AREAS...MAINLY EAST OF I-35...AND WILL BE DIURNALLY DRIVEN.
DRIER AND WARMER CONDITIONS ARE EXPECTED FRIDAY AND SATURDAY...
WITH HIGHS INCHING BACK CLOSER TO NORMAL.
ECMWF AND GFS BOTH INDICATE AN UPPER LEVEL RIDGE AMPLIFYING ACROSS
THE GREAT BASIN FRIDAY AND SATURDAY...DEEPENING A TROUGH THROUGH
THE CENTRAL PLAINS AND MISSISSIPPI RIVER VALLEY. THIS APPEARS TO
PUSH A RARE LATE JUNE COLD FRONT INTO NORTH-CENTRAL TEXAS SATURDAY
NIGHT. ECMWF IS FARTHER SOUTH WITH THE FRONT...REACHING THE
NORTHERN CWA SUNDAY. EVEN IF THE FRONT DOES NOT MAKE IT INTO THE
CWA...THE UPPER LEVEL PATTERN WILL BE CONDUCIVE FOR ANY ORGANIZED
UPSTREAM CONVECTION ACROSS NORTH OR WEST-CENTRAL TEXAS TO MAKE IT
INTO AT LEAST THE NORTHERN CWA LATE SATURDAY NIGHT AND SUNDAY AND
POTENTIALLY AGAIN SUNDAY NIGHT. A FARTHER SOUTHWARD SOLUTION LIKE
THE ECMWF HAS BEEN INDICATING WOULD ONLY FURTHER INCREASE POPS.
&&
.PRELIMINARY POINT TEMPS/POPS...
AUSTIN CAMP MABRY 73 90 73 90 74 / 10 20 - 10 -
AUSTIN BERGSTROM INTL AIRPORT 72 90 72 90 73 / 10 20 - 10 10
NEW BRAUNFELS MUNI AIRPORT 73 89 73 89 74 / 20 20 10 20 10
BURNET MUNI AIRPORT 72 89 72 88 73 / 10 10 - - -
DEL RIO INTL AIRPORT 73 89 74 89 75 / 40 40 20 20 20
GEORGETOWN MUNI AIRPORT 72 89 73 89 74 / 10 10 - - -
HONDO MUNI AIRPORT 73 88 73 88 74 / 30 20 10 20 10
SAN MARCOS MUNI AIRPORT 73 89 73 89 74 / 20 20 10 20 10
LA GRANGE - FAYETTE REGIONAL 74 90 74 89 75 / - 20 - 20 10
SAN ANTONIO INTL AIRPORT 74 89 74 88 75 / 20 20 10 20 -
STINSON MUNI AIRPORT 75 89 74 89 75 / 10 20 10 20 10
&&
.EWX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
MESOSCALE/AVIATION...ALLEN
SYNOPTIC/GRIDS...HAMPSHIRE
PUBLIC SERVICE/DATA COLLECTION...30
AREA FORECAST DISCUSSION...UPDATED
NWS BROWNSVILLE TX
1236 PM CDT MON JUN 22 2015
.DISCUSSION...UPDATED FOR LATEST AVIATION DISCUSSION BELOW.
&&
.AVIATION...MIDLEVEL CLOUD SHIELD CONTINUES TO OVERSPREAD THE
REGION...KEEPING TEMPERATURES JUST LOW ENOUGH TO INHIBIT LOWER CU
FIELD FORMATION. THIS HAS PUSHED BACK THE TIMING OF SHOWER
ACTIVITY INTO LATER THIS AFTERNOON. SOME OF THE LIGHT RAIN FROM
THIS MORNING REMAINS TO THE NW OF KMFE...AND WILL LIKELY REMAIN
AWAY FROM LOCAL AIRPORTS FOR THE NEXT SEVERAL HOURS. STILL HAVE
SOME VCTS FOR LATER THIS AFTERNOON DURING PEAK HEATING...BUT AREAL
COVERAGE LIKELY TOO LOW FOR PREDOMINANT RAIN IN TAFS. CIGS WILL
LOWER TO AROUND 2000 FT OVERNIGHT WITH WINDS LOWERING TO 5 TO
10KTS.
&&
.PREV DISCUSSION... /ISSUED 631 AM CDT MON JUN 22 2015/
DISCUSSION...UPDATED FOR LATEST AVIATION DISCUSSION BELOW.
AVIATION...INVERTED MID LEVEL TROUGH WILL REMAIN NEAR/OVER THE
AREA THROUGH MUCH OF THIS TAF PERIOD KEEPING MID/HIGH LEVEL CLOUDS
ACROSS DEEP SOUTH TEXAS AND A CHANCE FOR SHRA/TSRA ALTHOUGH
CONFIDENCE IS LOWERED TODAY IN ANY ONE TERMINAL BEING AFFECTED.
MVFR NOW WILL BECOME VFR BY MID MORNING AT WHICH TIME WINDS WILL
BEGIN TO PICK UP WITH 20 KNOTS GUSTS POSSIBLE THROUGH THE
AFTERNOON. WINDS WILL DECREASE AFTER SUNSET WITH MVFR RETURNING BY
MIDNIGHT.
PREV DISCUSSION... /ISSUED 356 AM CDT MON JUN 22 2015/
SHORT TERM.../NOW THROUGH TUESDAY/...THE AREA REMAINS UNDERNEATH
500MB INVERTED TROUGH WITH WEAK RIDGING LOCATED ACROSS THE SOUTHEAST
CONUS AND STRONGER RIDGING ACROSS THE SOUTHWEST CONUS. 00Z BRO
SOUNDING SHOWED 1.98 INCHES OF PWAT AND SOUTHEASTERLY WINDS UP
THROUGH 500MB. EARLY MORNING RADAR SHOWED SOUTHEASTERLY STREAMER
SHOWERS ACROSS THE GULF WATERS AND MOSTLY STRATIFORM RAIN IN
SOUTHERLY/SOUTHWESTERLY FLOW ON EAST SIDE OF THE INVERTED TROUGH
ACROSS MAINLY THE WESTERN HALF OF THE CWA. DON/T SEE ANY REASON WHY
SOME OF THAT PRECIPITATION WILL NOT MAKE IT INTO THE EASTERN HALF OF
THE CWA THIS MORNING. HRRR DOES SHOW THIS OCCURRING THIS MORNING. AS
SUCH...HAVE RAISED POPS THIS MORNING TO ACCOUNT FOR WHATS FALLING
NOW AND EXPAND EASTWARD THROUGH THE DAY. HIGHS DID NOT REACH FULL
POTENTIAL TODAY AND WITH EXPECTED CLOUD COVER HAVE DROPPED HIGHS A
FEW DEGREES TODAY...ESPECIALLY FURTHER WEST. WINDS WILL PICK UP
SLIGHTLY TODAY WITH TROUGHING OUT WEST INTERACTING WITH HIGH
PRESSURE ACROSS THE GULF.
MID LEVEL INVERTED TROUGH BEGINS TO MAKE SOME SLOW PROGRESS WESTWARD
AS HIGH PRESSURE STRENGTHENS TO OUR EAST AND BUILDS IN THROUGH THE
COASTAL WATERS. PWATS DO NOT REALLY FALL OFF AND REMAIN IN THE 1.9-
2.0 INCH RANGE THROUGH TUESDAY. GIVEN THE CLOSE PROXIMITY OF THE
TROUGH TO OUR WESTERN SECTIONS WILL ADD SLIGHT CHANCE POPS WEST
OVERNIGHT MONDAY NIGHT. ON TUESDAY A SURFACE TROUGH STRENGTHENS WITH
SFC WINDS BECOMING A LITTLE MORE ESE. ALONG WITH A LITTLE SPEED
CONVERGENCE THINK THE SEABREEZE WILL GET GOING TUESDAY LATE MORNING
THEN PROGRESS WESTWARD THROUGH THE AFTERNOON. HIGHS WILL BE AROUND A
DEGREE WARMER ON TUESDAY BUT HIGH CLOUDS SHOULD BE AROUND TO KEEP
HIGHS FROM REACHING THE MIDDLE 90S.
LONG TERM /TUESDAY NIGHT THROUGH SUNDAY/...NAM AND GFS INDICATE
ANOTHER SURFACE INVERTED TROUGH OR A NORTHWARD EXTENSION OF A
TROPICAL WAVE CROSSING THE BAY OF CAMPECHE TUESDAY NIGHT AND
WEDNESDAY. FORECAST SOUNDINGS CONTINUE TO SHOW MODEST MOISTURE
CONTENT PWATS 1.8 TO 2 INCHES AND GOOD INSTABILITY WITH NO CAP.
LIFT WILL BE INITIATED BY DAYTIME HEATING AND THE SEA BREEZE AS
WINDS BACK ESE AND WEAKEN WITH THE APPROACH AND WESTWARD TRACK OF
THE INVERTED SURFACE TROUGH. MODEL POP GUIDANCE ALSO ON THE BAND
WAGON WITH POPS AS HIGH AS 50 PERCENT WEDNESDAY AFTERNOON. A
BROAD BRUSH OF LOW END CHANCE POPS /30 PERCENT/ LOOK OK AT THIS
TIME WITH POSSIBLE LATER SHIFT BUMPING CHANCES UPWARD.
PRECIPIATION CHANCES FINALLY BEGIN TO TAPER OFF THURSDAY WITH
EVEN LOWER CHANCES FRIDAY AND SATURDAY. MOISTURE CONTENT LOWERS
AND A WESTWARD BUILDING OF THE BERMUDA HIGH TO WARM THE MID LAYERS
DEVELOPING A WEAK CAP. CAN NOT RULE ISOLATED ACTIVITY ALONG A SEA
BREEZE EACH DAY AND OVER THE COASTAL WATERS OVERNIGHT BUT CHANCES
WILL BE LIMITED ESPECIALLY FRIDAY AND THE BEGINNING OF THE
WEEKEND.
BY THE END OF THE WEEKEND AND EARLY NEXT WEEK...GFS ONCE AGAIN
SHOWS A TROPICAL WAVE OR WEAK LOW PRESSURE AREA OVER THE BAY OF
CAMPECHE. TROPICAL MOISTURE TO SEEP NORTHWARD ALONG THE WESTERN
PERIPHERY OF THE BERMUDA HIGH GIVING RISE TO ANOTHER SHOT
PRECIPITATION. CHANCES ARE LOW AT THIS TIME WITH ECMWF KEEPING
RAIN CHANCES AT BAY WITH MORE SUBSIDENCE OVER THE AREA MAINTAIN A
MORE DRIER SCENARIO.
FINALLY...TEMPERATURES LOOK TO BE SEASONAL WITH WARM MUGGY NIGHT
AND HOT HUMID DAYS. A BLEND OF THE MODEL GUIDANCE LOOKS WITHIN
REASON WITH GUIDANCE ONLY SEPERATE BY A DEGREE OR TWO THROUGH THE
LONG TERM.
MARINE...NOW THROUGH TUESDAY...MODERATE SOUTHEAST WINDS WILL
PREVAIL THROUGH THE PERIOD. LOW PRESSURE WILL STRENGTHEN TO OUR WEST
AND WITH HIGH PRESSURE ACROSS THE GULF WATERS WINDS WILL REAMIN
AROUND 12 TO 17 KNOTS THROUGH THE SHORT TERM PERIOD. THIS WILL KEEP
WAVE HEIGHTS FAIRLY CONSTANT WITH HEIGHTS OF 4 TO 5 FEET.
TUESDAY NIGHT THROUGH FRIDAY...MODELS IN GOOD AGREEMENT WITH BROAD
SURFACE HIGH PRESSURE OVER THE NORTHERN GULF AND WEAK LOWER
PRESSURE ACROSS THE BAY OF CAMPECHE. A LIGHT TO MODERATE SOUTHEAST
FLOW AND MODERATE TO SLIGHT SEAS TO PERSIST THROUGH THE PERIOD.
&&
.BRO WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
GM...NONE.
&&
$$
THIS PRODUCT IS ALSO AVAILABLE ON THE WEB AT:
HTTP://WEATHER.GOV/RGV
64/64
AREA FORECAST DISCUSSION
NWS AMARILLO TX
1230 PM CDT MON JUN 22 2015
.AVIATION...
18Z TAFS...AN UPPER-LEVEL RIDGE OF HIGH PRESSURE WILL MAINTAIN VFR
CONDITIONS THROUGH THE TAF PERIOD. BREEZY SOUTHWEST WINDS WILL GUST
TO AROUND 25 KTS THROUGH EARLY EVENING. THE GUSTS WILL SUBSIDE AFTER
SUNSET...BUT THEN PICK BACK UP BY MID TO LATE TUESDAY MORNING.
KB
&&
.PREV DISCUSSION... /ISSUED 319 AM CDT MON JUN 22 2015/
DISCUSSION...
LATEST WATER VAPOR IMAGERY WITH RAP 500 MB ANALYSIS OVERLAY SHOWS A
596 DM UPPER LEVEL HIGH CENTERED OVER CENTRAL NEW MEXICO. BROAD
SURFACE LOW WAS DEVELOPING OVER THE DAKOTAS AND NEBRASKA IN RESPONSE
TO A QUICK MOVING MID-UPPER WAVE IN THE NORTHERN PLAINS. SURFACE
TROUGH WILL SHIFT EASTWARD ACROSS THE CENTRAL PLAINS THROUGH THE
AFTERNOON ACCORDINGLY AND BECOME INCREASINGLY BAROCLINIC ACROSS
KANSAS. IN THE FAR NORTHWEST PORTION OF OUR AREA A WIND SHIFT MAY
OCCUR BUT LITTLE IMPACT ON TEMPERATURES IS EVIDENT IN SHORT RANGE
GUIDANCE. IN FACT...THIS MAY BE THE WARMEST SECTION OF THE AREA AS
LOW LEVEL MOISTURE SEEMS COMPARATIVELY SHALLOW AND MIXING BEING MOST
EFFECTIVE AT BRINGING DOWN DRY AIR. 100 DEGREES WILL PROBABLY BE
REACHED OR EXCEEDED AT OR NEAR BOISE CITY...GUYMON AND DALHART.
ELSEWHERE ACROSS THE AREA...THE POSITION OF UPPER HIGH MAY ALLOW
TEMPERATURES TO RISE ANOTHER COUPLE OF DEGREES ABOVE WHAT OCCURRED
YESTERDAY. USED PREVIOUS DAY MAXIMUM TEMPERATURE OBSERVATION
GRID...NUDGED SLIGHTLY UPWARD...AND MANUALLY ADJUSTED VALUES SLIGHTLY
BASED ON 850 TEMPERATURES SPATIAL CHANGES SEEN IN SHORT TERM MODEL
GUIDANCE.
SOME HIGH BASED CONVECTION MAY FORM NEAR THE RATON MESA LATE THIS
AFTERNOON ALONG AFOREMENTIONED CONVERGENT SURFACE BOUNDARY. IMPACTS
TO THE FAR NORTHWEST INCLUDING CIMARRON COUNTY SHOULD BE LIMITED TO
JUST CLOUD DEBRIS THIS EVENING.
THROUGH MID WEEK THE UPPER RIDGE WILL DRIFT EAST AND FLATTEN. 500 MB
HEIGHTS PEAK EARLY TUESDAY AND THEN DECREASE GRADUALLY. A MUCH MORE
AMPLIFIED UPPER FLOW PATTERN WILL EVOLVE LATE IN THE WEEK. FORECAST
UNCERTAINTY INCREASES DURING THE MIDDLE OF THE WEEK EVEN BEFORE
SIGNIFICANT AMPLIFICATION OF THE FLOW PATTERN OCCURS. WEAK DIFFICULT
TO RESOLVE SHORTWAVES WILL MOVE EAST-SOUTHEAST ON THE NORTHERN
PERIPHERY OF UPPER RIDGE. THESE MAY AID IN DEVELOPMENT OF CONVECTION
STARTING AS EARLY AS WEDNESDAY EVENING PARTICULARLY ACROSS THE NORTH.
A MORE PROMINENT SHORTWAVE WILL FORCE A WEAK COLD FRONT INTO THE
NORTHERN PORTION OF THE AREA THURSDAY NIGHT. THIS FRONT SHOULD
PROGRESS SLOWLY SOUTHWARD ACROSS THE AREA THROUGH FRIDAY AND BECOME
DIFFUSE ON SATURDAY PER MEDIUM RANGE MODEL CONSENSUS. THROUGH THIS
PERIOD MEAN FLOW WILL ONLY STRENGTHEN A LITTLE BUT WILL REMAIN FAIRLY
WEAK OVERALL MAKING IT DIFFICULT FOR OROGRAPHIC CONVECTION TO OUR
NORTHWEST TO PROPAGATE INTO THE AREA. MOST OF THE CONVECTION THAT
HAPPENS THURSDAY NIGHT THROUGH SATURDAY WILL PROBABLY BE DRIVEN BY
MOIST NORTHEASTERLY UPSLOPE SURFACE WINDS AND LOW LEVEL CONVERGENCE
IN WEAKLY CAPPED UNSTABLE ENVIRONMENT WITH A MAXIMA IN COVERAGE TIED
TO DIURNAL HEATING. WEAK DEEP LAYER SHEAR SHOULD LIMIT SEVERE
POTENTIAL BUT EFFICIENT RAIN PRODUCING THUNDERSTORMS MOVING SLOW SEEM
POSSIBLE IN A HIGH PWAT ENVIRONMENT (EXCEEDING 1.5 INCHES FRIDAY
NIGHT AND SATURDAY). THIS COULD LEAD TO A LOCALIZED FLOODING THREAT
ESPECIALLY IF STORMS BECOMES NUMEROUS ENOUGH. OTHERWISE NO WEATHER
HAZARDOUS ARE FORESEEN.
MEDIUM RANGE ENSEMBLE GUIDANCE IS IN AGREEMENT SUNDAY INTO EARLY
NEXT WEEK KEEPING THE AMPLIFIED NON-PROGRESSIVE PATTERN. POSITIVE
HEIGHT ANOMALIES WILL STAY TO OUR WEST AND SO TEMPERATURES SHOULD BE
AROUND NORMAL FOR LATE JUNE. WITH MEAN NORTHWESTERLY FLOW...ALBEIT
RELATIVELY WEAK...AND MOIST LOW LEVELS...COULD NOT JUSTIFY LOWER
THAN CLIMO PRECIPITATION PROBABILITIES DURING THIS PERIOD ESPECIALLY
ACROSS THE WESTERN SECTIONS SO HAVE CONTINUED 15-20 POP IN THE WEST.
BRB
&&
.AMA WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
OK...NONE.
&&
$$
08/02
AREA FORECAST DISCUSSION
NWS AUSTIN/SAN ANTONIO TX
941 AM CDT MON JUN 22 2015
.UPDATE...
SCATTERED AREAS OF MOSTLY LIGHT RAIN CONTINUE ACROSS SOUTH CENTRAL
TEXAS WITH ONE MODERATE NARROW BAND OF RAIN ACROSS MAVERICK AND
KINNEY COUNTIES. PRECIPITABLE WATER VALUES ARE A BIT LESS THAN
YESTERDAY AS SLIGHTLY DRIER AIR MOVES IN FROM THE WEST AS A 700 MB
RIDGE AXIS SLOWLY BUILDS INTO SOUTHEAST TEXAS. THERE WILL BE
ENOUGH HEATING AND MOISTURE FOR AFTERNOON CONVECTION...ESPECIALLY
WITH AN UPPER DISTURBANCE REMAINING TO OUR WEST...BUT RAIN RATES
SHOULD BE A BIT LESS AND PROBABLY NOT THE SAME AMOUNT OF COVERAGE
AS THE PREVIOUS COUPLE OF DAYS. RAINFALL AMOUNTS WILL AVERAGE LESS
THAN AN INCH BUT 1-2 INCHES WILL BE POSSIBLE FROM THE HEAVIEST
STORMS.
&&
.PREV DISCUSSION... /ISSUED 609 AM CDT MON JUN 22 2015/
AVIATION DISCUSSION...FOR 12Z TAF PACKAGE...
TSRA CURRENTLY OBSERVED ON RADAR AND SATELLITE IS MOVING NORTHWEST
AWAY FROM THE KSAT/KSSF TERMINALS. ADDITIONAL DEVELOPMENT THIS
MORNING WILL BE POSSIBLE SO INCLUDED VCTS IN THE MID MORNING
TIME FRAME AND PERSISTING THROUGH THE AFTERNOON. THE ISOLATED
NATURE OF THESE STORMS MAKE IT DIFFICULT TO HONE IN ON A
PREVAILING LINE.
CIG AND VIS IMPROVEMENT IS EXPECTED TO MVFR BY MID MORNING AS PER
PREVIOUS MORNINGS WITH A 4-5 KFT DECK IN PLACE MUCH OF THE DAY FOR
ALL TERMINALS. IFR CIGS ARE EXPECTED TO RETURN OVERNIGHT
TONIGHT...ESPECIALLY AT THE KSAT/KSSF TERMINALS.
PREV DISCUSSION... /ISSUED 324 AM CDT MON JUN 22 2015/
SHORT TERM (TODAY THROUGH TUESDAY)...MODELS HAVE HAD A HARD TIME
WITH THE EVOLUTION OF THE MID LEVEL CYCLONIC CIRCULATION ACROSS
MEXICO AND ASSOCIATED TROUGH AXIS EXTENDING THROUGH THE WESTERN
CWA. THE MID LEVEL LOW ACROSS MEXICO APPEARS TO BE CLOSER TO THE
RIO GRANDE THAN MODELS INDICATED YESTERDAY...LOCATED SOUTH OF
EAGLE PASS AND NORTHWEST OF LAREDO. A SLIGHT DRIFT NORTH OR
NORTHWEST IS EXPECTED TODAY BEFORE EVENTUALLY OPENING AND MOVING
WEST TUESDAY. DUE TO THE CLOSER PROXIMITY OF THE LOW AND SLOWER
EVOLUTION TO THE WEST...DRYING HAS BEEN DELAYED AND MID LEVEL
FORCING CONTINUES.
A SLIGHT DOWNWARD TREND IN ONGOING SHOWER ACTIVITY ACROSS THE
WESTERN CWA MAY TAKE PLACE THIS MORNING. THEN DE-STABILIZATION
THIS AFTERNOON COMBINED WITH MID LEVEL ASCENT ACROSS THE CENTRAL
AND WESTERN CWA SHOULD RESULT IN A SIMILAR REPEAT TO CONVECTION
FROM YESTERDAY. HRRR AGAIN DEPICTS THE I-35 CORRIDOR WITH QPF THIS
AFTERNOON AS WELL AS THE 00Z ECMWF...WHILE GFS AND NAM12 ARE MORE
ACROSS THE WINTER GARDEN AND WESTERN HILL COUNTRY REGION.
SCATTERED POPS HAVE BEEN INDICATED NEAR THE I-35 CORRIDOR COUNTIES
AND WESTWARD FOR THIS AFTERNOON...AND ACROSS THE WESTERN CWA
TONIGHT. SOME STORMS COULD PRODUCE QUICK...HEAVY DOWNPOURS TODAY
ALONG WITH SOME STRONGER WIND GUSTS...SIMILAR TO YESTERDAY.
ASSUMING THE MID LEVEL LOW DOES MOVE WEST AND OPEN TUESDAY...THERE
SHOULD BE A DOWNWARD TREND IN THE POPS ON TUESDAY...WITH MAINLY
ISOLATED COVERAGE...EXPECT CLOSE TO THE RIO GRANDE WHERE BETTER
MOISTURE POOLING AND WEAK FORCING MAY CONTINUE HIGHER COVERAGE.
CONTINUED BELOW NORMAL HIGH TEMPS FOR TODAY AND TUESDAY.
LONG TERM (TUESDAY NIGHT THROUGH SUNDAY)...POPS WEDNESDAY AND
THURSDAY WILL BE CONFINED MAINLY ACROSS SOUTHERN AND EASTERN
AREAS...MAINLY EAST OF I-35...AND WILL BE DIURNALLY DRIVEN.
DRIER AND WARMER CONDITIONS ARE EXPECTED FRIDAY AND SATURDAY...
WITH HIGHS INCHING BACK CLOSER TO NORMAL.
ECMWF AND GFS BOTH INDICATE AN UPPER LEVEL RIDGE AMPLIFYING ACROSS
THE GREAT BASIN FRIDAY AND SATURDAY...DEEPENING A TROUGH THROUGH
THE CENTRAL PLAINS AND MISSISSIPPI RIVER VALLEY. THIS APPEARS TO
PUSH A RARE LATE JUNE COLD FRONT INTO NORTH-CENTRAL TEXAS SATURDAY
NIGHT. ECMWF IS FARTHER SOUTH WITH THE FRONT...REACHING THE
NORTHERN CWA SUNDAY. EVEN IF THE FRONT DOES NOT MAKE IT INTO THE
CWA...THE UPPER LEVEL PATTERN WILL BE CONDUCIVE FOR ANY ORGANIZED
UPSTREAM CONVECTION ACROSS NORTH OR WEST-CENTRAL TEXAS TO MAKE IT
INTO AT LEAST THE NORTHERN CWA LATE SATURDAY NIGHT AND SUNDAY AND
POTENTIALLY AGAIN SUNDAY NIGHT. A FARTHER SOUTHWARD SOLUTION LIKE
THE ECMWF HAS BEEN INDICATING WOULD ONLY FURTHER INCREASE POPS.
&&
.PRELIMINARY POINT TEMPS/POPS...
AUSTIN CAMP MABRY 87 73 90 72 90 / 40 20 20 - 10
AUSTIN BERGSTROM INTL AIRPORT 87 72 90 71 90 / 40 20 20 - 10
NEW BRAUNFELS MUNI AIRPORT 87 73 90 72 90 / 40 20 20 - 20
BURNET MUNI AIRPORT 87 72 89 71 89 / 30 20 10 - 10
DEL RIO INTL AIRPORT 87 73 89 73 89 / 40 40 30 30 20
GEORGETOWN MUNI AIRPORT 87 72 90 71 89 / 30 20 10 - 10
HONDO MUNI AIRPORT 86 72 89 72 89 / 40 20 20 10 20
SAN MARCOS MUNI AIRPORT 87 73 90 72 89 / 40 20 20 - 20
LA GRANGE - FAYETTE REGIONAL 90 74 90 73 90 / 20 10 20 - 30
SAN ANTONIO INTL AIRPORT 86 74 90 74 89 / 40 20 20 10 20
STINSON MUNI AIRPORT 86 74 90 73 90 / 40 20 20 10 20
&&
.EWX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
MESOSCALE/AVIATION...ALLEN
SYNOPTIC/GRIDS...HAMPSHIRE
PUBLIC SERVICE/DATA COLLECTION...30
AREA FORECAST DISCUSSION
NWS BROWNSVILLE TX
631 AM CDT MON JUN 22 2015
.DISCUSSION...UPDATED FOR LATEST AVIATION DISCUSSION BELOW.
&&
.AVIATION...INVERTED MID LEVEL TROUGH WILL REMAIN NEAR/OVER THE
AREA THROUGH MUCH OF THIS TAF PERIOD KEEPING MID/HIGH LEVEL CLOUDS
ACROSS DEEP SOUTH TEXAS AND A CHANCE FOR SHRA/TSRA ALTHOUGH
CONFIDENCE IS LOWERED TODAY IN ANY ONE TERMINAL BEING AFFECTED.
MVFR NOW WILL BECOME VFR BY MID MORNING AT WHICH TIME WINDS WILL
BEGIN TO PICK UP WITH 20 KNOTS GUSTS POSSIBLE THROUGH THE
AFTERNOON. WINDS WILL DECREASE AFTER SUNSET WITH MVFR RETURNING BY
MIDNIGHT.
&&
.PREV DISCUSSION... /ISSUED 356 AM CDT MON JUN 22 2015/
SHORT TERM.../NOW THROUGH TUESDAY/...THE AREA REMAINS UNDERNEATH
500MB INVERTED TROUGH WITH WEAK RIDGING LOCATED ACROSS THE SOUTHEAST
CONUS AND STRONGER RIDGING ACROSS THE SOUTHWEST CONUS. 00Z BRO
SOUNDING SHOWED 1.98 INCHES OF PWAT AND SOUTHEASTERLY WINDS UP
THROUGH 500MB. EARLY MORNING RADAR SHOWED SOUTHEASTERLY STREAMER
SHOWERS ACROSS THE GULF WATERS AND MOSTLY STRATIFORM RAIN IN
SOUTHERLY/SOUTHWESTERLY FLOW ON EAST SIDE OF THE INVERTED TROUGH
ACROSS MAINLY THE WESTERN HALF OF THE CWA. DON/T SEE ANY REASON WHY
SOME OF THAT PRECIPITATION WILL NOT MAKE IT INTO THE EASTERN HALF OF
THE CWA THIS MORNING. HRRR DOES SHOW THIS OCCURRING THIS MORNING. AS
SUCH...HAVE RAISED POPS THIS MORNING TO ACCOUNT FOR WHATS FALLING
NOW AND EXPAND EASTWARD THROUGH THE DAY. HIGHS DID NOT REACH FULL
POTENTIAL TODAY AND WITH EXPECTED CLOUD COVER HAVE DROPPED HIGHS A
FEW DEGREES TODAY...ESPECIALLY FURTHER WEST. WINDS WILL PICK UP
SLIGHTLY TODAY WITH TROUGHING OUT WEST INTERACTING WITH HIGH
PRESSURE ACROSS THE GULF.
MID LEVEL INVERTED TROUGH BEGINS TO MAKE SOME SLOW PROGRESS WESTWARD
AS HIGH PRESSURE STRENGTHENS TO OUR EAST AND BUILDS IN THROUGH THE
COASTAL WATERS. PWATS DO NOT REALLY FALL OFF AND REMAIN IN THE 1.9-
2.0 INCH RANGE THROUGH TUESDAY. GIVEN THE CLOSE PROXIMITY OF THE
TROUGH TO OUR WESTERN SECTIONS WILL ADD SLIGHT CHANCE POPS WEST
OVERNIGHT MONDAY NIGHT. ON TUESDAY A SURFACE TROUGH STRENGTHENS WITH
SFC WINDS BECOMING A LITTLE MORE ESE. ALONG WITH A LITTLE SPEED
CONVERGENCE THINK THE SEABREEZE WILL GET GOING TUESDAY LATE MORNING
THEN PROGRESS WESTWARD THROUGH THE AFTERNOON. HIGHS WILL BE AROUND A
DEGREE WARMER ON TUESDAY BUT HIGH CLOUDS SHOULD BE AROUND TO KEEP
HIGHS FROM REACHING THE MIDDLE 90S.
LONG TERM /TUESDAY NIGHT THROUGH SUNDAY/...NAM AND GFS INDICATE
ANOTHER SURFACE INVERTED TROUGH OR A NORTHWARD EXTENSION OF A
TROPICAL WAVE CROSSING THE BAY OF CAMPECHE TUESDAY NIGHT AND
WEDNESDAY. FORECAST SOUNDINGS CONTINUE TO SHOW MODEST MOISTURE
CONTENT PWATS 1.8 TO 2 INCHES AND GOOD INSTABILITY WITH NO CAP.
LIFT WILL BE INITIATED BY DAYTIME HEATING AND THE SEA BREEZE AS
WINDS BACK ESE AND WEAKEN WITH THE APPROACH AND WESTWARD TRACK OF
THE INVERTED SURFACE TROUGH. MODEL POP GUIDANCE ALSO ON THE BAND
WAGON WITH POPS AS HIGH AS 50 PERCENT WEDNESDAY AFTERNOON. A
BROAD BRUSH OF LOW END CHANCE POPS /30 PERCENT/ LOOK OK AT THIS
TIME WITH POSSIBLE LATER SHIFT BUMPING CHANCES UPWARD.
PRECIPIATION CHANCES FINALLY BEGIN TO TAPER OFF THURSDAY WITH
EVEN LOWER CHANCES FRIDAY AND SATURDAY. MOISTURE CONTENT LOWERS
AND A WESTWARD BUILDING OF THE BERMUDA HIGH TO WARM THE MID LAYERS
DEVELOPING A WEAK CAP. CAN NOT RULE ISOLATED ACTIVITY ALONG A SEA
BREEZE EACH DAY AND OVER THE COASTAL WATERS OVERNIGHT BUT CHANCES
WILL BE LIMITED ESPECIALLY FRIDAY AND THE BEGINNING OF THE
WEEKEND.
BY THE END OF THE WEEKEND AND EARLY NEXT WEEK...GFS ONCE AGAIN
SHOWS A TROPICAL WAVE OR WEAK LOW PRESSURE AREA OVER THE BAY OF
CAMPECHE. TROPICAL MOISTURE TO SEEP NORTHWARD ALONG THE WESTERN
PERIPHERY OF THE BERMUDA HIGH GIVING RISE TO ANOTHER SHOT
PRECIPITATION. CHANCES ARE LOW AT THIS TIME WITH ECMWF KEEPING
RAIN CHANCES AT BAY WITH MORE SUBSIDENCE OVER THE AREA MAINTAIN A
MORE DRIER SCENARIO.
FINALLY...TEMPERATURES LOOK TO BE SEASONAL WITH WARM MUGGY NIGHT
AND HOT HUMID DAYS. A BLEND OF THE MODEL GUIDANCE LOOKS WITHIN
REASON WITH GUIDANCE ONLY SEPERATE BY A DEGREE OR TWO THROUGH THE
LONG TERM.
MARINE...NOW THROUGH TUESDAY...MODERATE SOUTHEAST WINDS WILL
PREVAIL THROUGH THE PERIOD. LOW PRESSURE WILL STRENGTHEN TO OUR WEST
AND WITH HIGH PRESSURE ACROSS THE GULF WATERS WINDS WILL REAMIN
AROUND 12 TO 17 KNOTS THROUGH THE SHORT TERM PERIOD. THIS WILL KEEP
WAVE HEIGHTS FAIRLY CONSTANT WITH HEIGHTS OF 4 TO 5 FEET.
TUESDAY NIGHT THROUGH FRIDAY...MODELS IN GOOD AGREEMENT WITH BROAD
SURFACE HIGH PRESSURE OVER THE NORTHERN GULF AND WEAK LOWER
PRESSURE ACROSS THE BAY OF CAMPECHE. A LIGHT TO MODERATE SOUTHEAST
FLOW AND MODERATE TO SLIGHT SEAS TO PERSIST THROUGH THE PERIOD.
&&
.BRO WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
GM...NONE.
&&
$$
THIS PRODUCT IS ALSO AVAILABLE ON THE WEB AT:
HTTP://WEATHER.GOV/RGV
55
AREA FORECAST DISCUSSION
NWS AUSTIN/SAN ANTONIO TX
609 AM CDT MON JUN 22 2015
.AVIATION DISCUSSION...FOR 12Z TAF PACKAGE...
TSRA CURRENTLY OBSERVED ON RADAR AND SATELLITE IS MOVING NORTHWEST
AWAY FROM THE KSAT/KSSF TERMINALS. ADDITIONAL DEVELOPMENT THIS
MORNING WILL BE POSSIBLE SO INCLUDED VCTS IN THE MID MORNING
TIME FRAME AND PERSISTING THROUGH THE AFTERNOON. THE ISOLATED
NATURE OF THESE STORMS MAKE IT DIFFICULT TO HONE IN ON A
PREVAILING LINE.
CIG AND VIS IMPROVEMENT IS EXPECTED TO MVFR BY MID MORNING AS PER
PREVIOUS MORNINGS WITH A 4-5 KFT DECK IN PLACE MUCH OF THE DAY FOR
ALL TERMINALS. IFR CIGS ARE EXPECTED TO RETURN OVERNIGHT
TONIGHT...ESPECIALLY AT THE KSAT/KSSF TERMINALS.
&&
.PREV DISCUSSION... /ISSUED 324 AM CDT MON JUN 22 2015/
SHORT TERM (TODAY THROUGH TUESDAY)...MODELS HAVE HAD A HARD TIME
WITH THE EVOLUTION OF THE MID LEVEL CYCLONIC CIRCULATION ACROSS
MEXICO AND ASSOCIATED TROUGH AXIS EXTENDING THROUGH THE WESTERN
CWA. THE MID LEVEL LOW ACROSS MEXICO APPEARS TO BE CLOSER TO THE
RIO GRANDE THAN MODELS INDICATED YESTERDAY...LOCATED SOUTH OF
EAGLE PASS AND NORTHWEST OF LAREDO. A SLIGHT DRIFT NORTH OR
NORTHWEST IS EXPECTED TODAY BEFORE EVENTUALLY OPENING AND MOVING
WEST TUESDAY. DUE TO THE CLOSER PROXIMITY OF THE LOW AND SLOWER
EVOLUTION TO THE WEST...DRYING HAS BEEN DELAYED AND MID LEVEL
FORCING CONTINUES.
A SLIGHT DOWNWARD TREND IN ONGOING SHOWER ACTIVITY ACROSS THE
WESTERN CWA MAY TAKE PLACE THIS MORNING. THEN DE-STABILIZATION
THIS AFTERNOON COMBINED WITH MID LEVEL ASCENT ACROSS THE CENTRAL
AND WESTERN CWA SHOULD RESULT IN A SIMILAR REPEAT TO CONVECTION
FROM YESTERDAY. HRRR AGAIN DEPICTS THE I-35 CORRIDOR WITH QPF THIS
AFTERNOON AS WELL AS THE 00Z ECMWF...WHILE GFS AND NAM12 ARE MORE
ACROSS THE WINTER GARDEN AND WESTERN HILL COUNTRY REGION.
SCATTERED POPS HAVE BEEN INDICATED NEAR THE I-35 CORRIDOR COUNTIES
AND WESTWARD FOR THIS AFTERNOON...AND ACROSS THE WESTERN CWA
TONIGHT. SOME STORMS COULD PRODUCE QUICK...HEAVY DOWNPOURS TODAY
ALONG WITH SOME STRONGER WIND GUSTS...SIMILAR TO YESTERDAY.
ASSUMING THE MID LEVEL LOW DOES MOVE WEST AND OPEN TUESDAY...THERE
SHOULD BE A DOWNWARD TREND IN THE POPS ON TUESDAY...WITH MAINLY
ISOLATED COVERAGE...EXPECT CLOSE TO THE RIO GRANDE WHERE BETTER
MOISTURE POOLING AND WEAK FORCING MAY CONTINUE HIGHER COVERAGE.
CONTINUED BELOW NORMAL HIGH TEMPS FOR TODAY AND TUESDAY.
LONG TERM (TUESDAY NIGHT THROUGH SUNDAY)...POPS WEDNESDAY AND
THURSDAY WILL BE CONFINED MAINLY ACROSS SOUTHERN AND EASTERN
AREAS...MAINLY EAST OF I-35...AND WILL BE DIURNALLY DRIVEN.
DRIER AND WARMER CONDITIONS ARE EXPECTED FRIDAY AND SATURDAY...
WITH HIGHS INCHING BACK CLOSER TO NORMAL.
ECMWF AND GFS BOTH INDICATE AN UPPER LEVEL RIDGE AMPLIFYING ACROSS
THE GREAT BASIN FRIDAY AND SATURDAY...DEEPENING A TROUGH THROUGH
THE CENTRAL PLAINS AND MISSISSIPPI RIVER VALLEY. THIS APPEARS TO
PUSH A RARE LATE JUNE COLD FRONT INTO NORTH-CENTRAL TEXAS SATURDAY
NIGHT. ECMWF IS FARTHER SOUTH WITH THE FRONT...REACHING THE
NORTHERN CWA SUNDAY. EVEN IF THE FRONT DOES NOT MAKE IT INTO THE
CWA...THE UPPER LEVEL PATTERN WILL BE CONDUCIVE FOR ANY ORGANIZED
UPSTREAM CONVECTION ACROSS NORTH OR WEST-CENTRAL TEXAS TO MAKE IT
INTO AT LEAST THE NORTHERN CWA LATE SATURDAY NIGHT AND SUNDAY AND
POTENTIALLY AGAIN SUNDAY NIGHT. A FARTHER SOUTHWARD SOLUTION LIKE
THE ECMWF HAS BEEN INDICATING WOULD ONLY FURTHER INCREASE POPS.
&&
.PRELIMINARY POINT TEMPS/POPS...
AUSTIN CAMP MABRY 89 73 90 72 90 / 40 20 20 - 10
AUSTIN BERGSTROM INTL AIRPORT 89 72 90 71 90 / 40 20 20 - 10
NEW BRAUNFELS MUNI AIRPORT 88 73 90 72 90 / 40 20 20 - 20
BURNET MUNI AIRPORT 88 72 89 71 89 / 30 20 10 - 10
DEL RIO INTL AIRPORT 89 73 89 73 89 / 30 40 30 30 20
GEORGETOWN MUNI AIRPORT 89 72 90 71 89 / 30 20 10 - 10
HONDO MUNI AIRPORT 88 72 89 72 89 / 40 20 20 10 20
SAN MARCOS MUNI AIRPORT 88 73 90 72 89 / 40 20 20 - 20
LA GRANGE - FAYETTE REGIONAL 90 74 90 73 90 / 20 10 20 - 30
SAN ANTONIO INTL AIRPORT 88 74 90 74 89 / 40 20 20 10 20
STINSON MUNI AIRPORT 88 74 90 73 90 / 40 20 20 10 20
&&
.EWX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
MESOSCALE/AVIATION...TB3
SYNOPTIC/GRIDS...RUNYEN
AREA FORECAST DISCUSSION
NWS BROWNSVILLE TX
356 AM CDT MON JUN 22 2015
.SHORT TERM.../NOW THROUGH TUESDAY/...THE AREA REMAINS UNDERNEATH
500MB INVERTED TROUGH WITH WEAK RIDGING LOCATED ACROSS THE SOUTHEAST
CONUS AND STRONGER RIDGING ACROSS THE SOUTHWEST CONUS. 00Z BRO
SOUNDING SHOWED 1.98 INCHES OF PWAT AND SOUTHEASTERLY WINDS UP
THROUGH 500MB. EARLY MORNING RADAR SHOWED SOUTHEASTERLY STREAMER
SHOWERS ACROSS THE GULF WATERS AND MOSTLY STRATIFORM RAIN IN
SOUTHERLY/SOUTHWESTERLY FLOW ON EAST SIDE OF THE INVERTED TROUGH
ACROSS MAINLY THE WESTERN HALF OF THE CWA. DON/T SEE ANY REASON WHY
SOME OF THAT PRECIPITATION WILL NOT MAKE IT INTO THE EASTERN HALF OF
THE CWA THIS MORNING. HRRR DOES SHOW THIS OCCURRING THIS MORNING. AS
SUCH...HAVE RAISED POPS THIS MORNING TO ACCOUNT FOR WHATS FALLING
NOW AND EXPAND EASTWARD THROUGH THE DAY. HIGHS DID NOT REACH FULL
POTENTIAL TODAY AND WITH EXPECTED CLOUD COVER HAVE DROPPED HIGHS A
FEW DEGREES TODAY...ESPECIALLY FURTHER WEST. WINDS WILL PICK UP
SLIGHTLY TODAY WITH TROUGHING OUT WEST INTERACTING WITH HIGH
PRESSURE ACROSS THE GULF.
MID LEVEL INVERTED TROUGH BEGINS TO MAKE SOME SLOW PROGRESS WESTWARD
AS HIGH PRESSURE STRENGTHENS TO OUR EAST AND BUILDS IN THROUGH THE
COASTAL WATERS. PWATS DO NOT REALLY FALL OFF AND REMAIN IN THE 1.9-
2.0 INCH RANGE THROUGH TUESDAY. GIVEN THE CLOSE PROXIMITY OF THE
TROUGH TO OUR WESTERN SECTIONS WILL ADD SLIGHT CHANCE POPS WEST
OVERNIGHT MONDAY NIGHT. ON TUESDAY A SURFACE TROUGH STRENGTHENS WITH
SFC WINDS BECOMING A LITTLE MORE ESE. ALONG WITH A LITTLE SPEED
CONVERGENCE THINK THE SEABREEZE WILL GET GOING TUESDAY LATE MORNING
THEN PROGRESS WESTWARD THROUGH THE AFTERNOON. HIGHS WILL BE AROUND A
DEGREE WARMER ON TUESDAY BUT HIGH CLOUDS SHOULD BE AROUND TO KEEP
HIGHS FROM REACHING THE MIDDLE 90S.
.LONG TERM /TUESDAY NIGHT THROUGH SUNDAY/...NAM AND GFS INDICATE
ANOTHER SURFACE INVERTED TROUGH OR A NORTHWARD EXTENSION OF A
TROPICAL WAVE CROSSING THE BAY OF CAMPECHE TUESDAY NIGHT AND
WEDNESDAY. FORECAST SOUNDINGS CONTINUE TO SHOW MODEST MOISTURE
CONTENT PWATS 1.8 TO 2 INCHES AND GOOD INSTABILITY WITH NO CAP.
LIFT WILL BE INITIATED BY DAYTIME HEATING AND THE SEA BREEZE AS
WINDS BACK ESE AND WEAKEN WITH THE APPROACH AND WESTWARD TRACK OF
THE INVERTED SURFACE TROUGH. MODEL POP GUIDANCE ALSO ON THE BAND
WAGON WITH POPS AS HIGH AS 50 PERCENT WEDNESDAY AFTERNOON. A
BROAD BRUSH OF LOW END CHANCE POPS /30 PERCENT/ LOOK OK AT THIS
TIME WITH POSSIBLE LATER SHIFT BUMPING CHANCES UPWARD.
PRECIPIATION CHANCES FINALLY BEGIN TO TAPER OFF THURSDAY WITH
EVEN LOWER CHANCES FRIDAY AND SATURDAY. MOISTURE CONTENT LOWERS
AND A WESTWARD BUILDING OF THE BERMUDA HIGH TO WARM THE MID LAYERS
DEVELOPING A WEAK CAP. CAN NOT RULE ISOLATED ACTIVITY ALONG A SEA
BREEZE EACH DAY AND OVER THE COASTAL WATERS OVERNIGHT BUT CHANCES
WILL BE LIMITED ESPECIALLY FRIDAY AND THE BEGINNING OF THE
WEEKEND.
BY THE END OF THE WEEKEND AND EARLY NEXT WEEK...GFS ONCE AGAIN
SHOWS A TROPICAL WAVE OR WEAK LOW PRESSURE AREA OVER THE BAY OF
CAMPECHE. TROPICAL MOISTURE TO SEEP NORTHWARD ALONG THE WESTERN
PERIPHERY OF THE BERMUDA HIGH GIVING RISE TO ANOTHER SHOT
PRECIPITATION. CHANCES ARE LOW AT THIS TIME WITH ECMWF KEEPING
RAIN CHANCES AT BAY WITH MORE SUBSIDENCE OVER THE AREA MAINTAIN A
MORE DRIER SCENARIO.
FINALLY...TEMPERATURES LOOK TO BE SEASONAL WITH WARM MUGGY NIGHT
AND HOT HUMID DAYS. A BLEND OF THE MODEL GUIDANCE LOOKS WITHIN
REASON WITH GUIDANCE ONLY SEPERATE BY A DEGREE OR TWO THROUGH THE
LONG TERM.
&&
.MARINE...NOW THROUGH TUESDAY...MODERATE SOUTHEAST WINDS WILL
PREVAIL THROUGH THE PERIOD. LOW PRESSURE WILL STRENGTHEN TO OUR WEST
AND WITH HIGH PRESSURE ACROSS THE GULF WATERS WINDS WILL REAMIN
AROUND 12 TO 17 KNOTS THROUGH THE SHORT TERM PERIOD. THIS WILL KEEP
WAVE HEIGHTS FAIRLY CONSTANT WITH HEIGHTS OF 4 TO 5 FEET.
TUESDAY NIGHT THROUGH FRIDAY...MODELS IN GOOD AGREEMENT WITH BROAD
SURFACE HIGH PRESSURE OVER THE NORTHERN GULF AND WEAK LOWER
PRESSURE ACROSS THE BAY OF CAMPECHE. A LIGHT TO MODERATE SOUTHEAST
FLOW AND MODERATE TO SLIGHT SEAS TO PERSIST THROUGH THE PERIOD.
&&
.PRELIMINARY POINT TEMPS/POPS...
BAYVIEW/PORT ISABEL 91 79 90 79 / 20 10 10 20
BROWNSVILLE 92 78 93 79 / 30 10 20 20
HARLINGEN 93 77 93 77 / 30 10 20 20
MCALLEN 94 78 94 78 / 30 10 20 10
RIO GRANDE CITY 93 77 94 77 / 30 20 20 10
SOUTH PADRE ISLAND 88 80 87 79 / 20 10 10 20
&&
.BRO WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
GM...NONE.
&&
$$
THIS PRODUCT IS ALSO AVAILABLE ON THE WEB AT:
HTTP://WEATHER.GOV/RGV
55...SHORT TERM
59...LONG TERM
58...GRAPHICS
AREA FORECAST DISCUSSION
NWS AUSTIN/SAN ANTONIO TX
324 AM CDT MON JUN 22 2015
.SHORT TERM (TODAY THROUGH TUESDAY)...MODELS HAVE HAD A HARD TIME
WITH THE EVOLUTION OF THE MID LEVEL CYCLONIC CIRCULATION ACROSS
MEXICO AND ASSOCIATED TROUGH AXIS EXTENDING THROUGH THE WESTERN
CWA. THE MID LEVEL LOW ACROSS MEXICO APPEARS TO BE CLOSER TO THE
RIO GRANDE THAN MODELS INDICATED YESTERDAY...LOCATED SOUTH OF
EAGLE PASS AND NORTHWEST OF LAREDO. A SLIGHT DRIFT NORTH OR
NORTHWEST IS EXPECTED TODAY BEFORE EVENTUALLY OPENING AND MOVING
WEST TUESDAY. DUE TO THE CLOSER PROXIMITY OF THE LOW AND SLOWER
EVOLUTION TO THE WEST...DRYING HAS BEEN DELAYED AND MID LEVEL
FORCING CONTINUES.
A SLIGHT DOWNWARD TREND IN ONGOING SHOWER ACTIVITY ACROSS THE
WESTERN CWA MAY TAKE PLACE THIS MORNING. THEN DE-STABILIZATION
THIS AFTERNOON COMBINED WITH MID LEVEL ASCENT ACROSS THE CENTRAL
AND WESTERN CWA SHOULD RESULT IN A SIMILAR REPEAT TO CONVECTION
FROM YESTERDAY. HRRR AGAIN DEPICTS THE I-35 CORRIDOR WITH QPF THIS
AFTERNOON AS WELL AS THE 00Z ECMWF...WHILE GFS AND NAM12 ARE MORE
ACROSS THE WINTER GARDEN AND WESTERN HILL COUNTRY REGION.
SCATTERED POPS HAVE BEEN INDICATED NEAR THE I-35 CORRIDOR COUNTIES
AND WESTWARD FOR THIS AFTERNOON...AND ACROSS THE WESTERN CWA
TONIGHT. SOME STORMS COULD PRODUCE QUICK...HEAVY DOWNPOURS TODAY
ALONG WITH SOME STRONGER WIND GUSTS...SIMILAR TO YESTERDAY.
ASSUMING THE MID LEVEL LOW DOES MOVE WEST AND OPEN TUESDAY...THERE
SHOULD BE A DOWNWARD TREND IN THE POPS ON TUESDAY...WITH MAINLY
ISOLATED COVERAGE...EXPECT CLOSE TO THE RIO GRANDE WHERE BETTER
MOISTURE POOLING AND WEAK FORCING MAY CONTINUE HIGHER COVERAGE.
CONTINUED BELOW NORMAL HIGH TEMPS FOR TODAY AND TUESDAY.
&&
.LONG TERM (TUESDAY NIGHT THROUGH SUNDAY)...POPS WEDNESDAY AND
THURSDAY WILL BE CONFINED MAINLY ACROSS SOUTHERN AND EASTERN
AREAS...MAINLY EAST OF I-35...AND WILL BE DIURNALLY DRIVEN.
DRIER AND WARMER CONDITIONS ARE EXPECTED FRIDAY AND SATURDAY...
WITH HIGHS INCHING BACK CLOSER TO NORMAL.
ECMWF AND GFS BOTH INDICATE AN UPPER LEVEL RIDGE AMPLIFYING ACROSS
THE GREAT BASIN FRIDAY AND SATURDAY...DEEPENING A TROUGH THROUGH
THE CENTRAL PLAINS AND MISSISSIPPI RIVER VALLEY. THIS APPEARS TO
PUSH A RARE LATE JUNE COLD FRONT INTO NORTH-CENTRAL TEXAS SATURDAY
NIGHT. ECMWF IS FARTHER SOUTH WITH THE FRONT...REACHING THE
NORTHERN CWA SUNDAY. EVEN IF THE FRONT DOES NOT MAKE IT INTO THE
CWA...THE UPPER LEVEL PATTERN WILL BE CONDUCIVE FOR ANY ORGANIZED
UPSTREAM CONVECTION ACROSS NORTH OR WEST-CENTRAL TEXAS TO MAKE IT
INTO AT LEAST THE NORTHERN CWA LATE SATURDAY NIGHT AND SUNDAY AND
POTENTIALLY AGAIN SUNDAY NIGHT. A FARTHER SOUTHWARD SOLUTION LIKE
THE ECMWF HAS BEEN INDICATING WOULD ONLY FURTHER INCREASE POPS.
&&
.PRELIMINARY POINT TEMPS/POPS...
AUSTIN CAMP MABRY 89 73 90 72 90 / 40 20 20 - 10
AUSTIN BERGSTROM INTL AIRPORT 89 72 90 71 90 / 40 20 20 - 10
NEW BRAUNFELS MUNI AIRPORT 88 73 90 72 90 / 40 20 20 - 20
BURNET MUNI AIRPORT 88 72 89 71 89 / 30 20 10 - 10
DEL RIO INTL AIRPORT 89 73 89 73 89 / 30 40 30 30 20
GEORGETOWN MUNI AIRPORT 89 72 90 71 89 / 30 20 10 - 10
HONDO MUNI AIRPORT 88 72 89 72 89 / 40 20 20 10 20
SAN MARCOS MUNI AIRPORT 88 73 90 72 89 / 40 20 20 - 20
LA GRANGE - FAYETTE REGIONAL 90 74 90 73 90 / 20 10 20 - 30
SAN ANTONIO INTL AIRPORT 88 74 90 74 89 / 40 20 20 10 20
STINSON MUNI AIRPORT 88 74 90 73 90 / 40 20 20 10 20
&&
.EWX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
MESOSCALE/AVIATION...TB3
SYNOPTIC/GRIDS...RUNYEN
AREA FORECAST DISCUSSION
NWS AMARILLO TX
319 AM CDT MON JUN 22 2015
.DISCUSSION...
LATEST WATER VAPOR IMAGERY WITH RAP 500 MB ANALYSIS OVERLAY SHOWS A
596 DM UPPER LEVEL HIGH CENTERED OVER CENTRAL NEW MEXICO. BROAD
SURFACE LOW WAS DEVELOPING OVER THE DAKOTAS AND NEBRASKA IN RESPONSE
TO A QUICK MOVING MID-UPPER WAVE IN THE NORTHERN PLAINS. SURFACE
TROUGH WILL SHIFT EASTWARD ACROSS THE CENTRAL PLAINS THROUGH THE
AFTERNOON ACCORDINGLY AND BECOME INCREASINGLY BAROCLINIC ACROSS
KANSAS. IN THE FAR NORTHWEST PORTION OF OUR AREA A WIND SHIFT MAY
OCCUR BUT LITTLE IMPACT ON TEMPERATURES IS EVIDENT IN SHORT RANGE
GUIDANCE. IN FACT...THIS MAY BE THE WARMEST SECTION OF THE AREA AS
LOW LEVEL MOISTURE SEEMS COMPARATIVELY SHALLOW AND MIXING BEING MOST
EFFECTIVE AT BRINGING DOWN DRY AIR. 100 DEGREES WILL PROBABLY BE
REACHED OR EXCEEDED AT OR NEAR BOISE CITY...GUYMON AND DALHART.
ELSEWHERE ACROSS THE AREA...THE POSITION OF UPPER HIGH MAY ALLOW
TEMPERATURES TO RISE ANOTHER COUPLE OF DEGREES ABOVE WHAT OCCURRED
YESTERDAY. USED PREVIOUS DAY MAXIMUM TEMPERATURE OBSERVATION
GRID...NUDGED SLIGHTLY UPWARD...AND MANUALLY ADJUSTED VALUES SLIGHTLY
BASED ON 850 TEMPERATURES SPATIAL CHANGES SEEN IN SHORT TERM MODEL
GUIDANCE.
SOME HIGH BASED CONVECTION MAY FORM NEAR THE RATON MESA LATE THIS
AFTERNOON ALONG AFOREMENTIONED CONVERGENT SURFACE BOUNDARY. IMPACTS
TO THE FAR NORTHWEST INCLUDING CIMARRON COUNTY SHOULD BE LIMITED TO
JUST CLOUD DEBRIS THIS EVENING.
THROUGH MID WEEK THE UPPER RIDGE WILL DRIFT EAST AND FLATTEN. 500 MB
HEIGHTS PEAK EARLY TUESDAY AND THEN DECREASE GRADUALLY. A MUCH MORE
AMPLIFIED UPPER FLOW PATTERN WILL EVOLVE LATE IN THE WEEK. FORECAST
UNCERTAINTY INCREASES DURING THE MIDDLE OF THE WEEK EVEN BEFORE
SIGNIFICANT AMPLIFICATION OF THE FLOW PATTERN OCCURS. WEAK DIFFICULT
TO RESOLVE SHORTWAVES WILL MOVE EAST-SOUTHEAST ON THE NORTHERN
PERIPHERY OF UPPER RIDGE. THESE MAY AID IN DEVELOPMENT OF CONVECTION
STARTING AS EARLY AS WEDNESDAY EVENING PARTICULARLY ACROSS THE NORTH.
A MORE PROMINENT SHORTWAVE WILL FORCE A WEAK COLD FRONT INTO THE
NORTHERN PORTION OF THE AREA THURSDAY NIGHT. THIS FRONT SHOULD
PROGRESS SLOWLY SOUTHWARD ACROSS THE AREA THROUGH FRIDAY AND BECOME
DIFFUSE ON SATURDAY PER MEDIUM RANGE MODEL CONSENSUS. THROUGH THIS
PERIOD MEAN FLOW WILL ONLY STRENGTHEN A LITTLE BUT WILL REMAIN FAIRLY
WEAK OVERALL MAKING IT DIFFICULT FOR ORGAGRAPHIC CONVECTION TO OUR
NORTHWEST TO PROPAGATE INTO THE AREA. MOST OF THE CONVECTION THAT
HAPPENS THURSDAY NIGHT THROUGH SATURDAY WILL PROBABLY BE DRIVEN BY
MOIST NORTHEASTERLY UPSLOPE SURFACE WINDS AND LOW LEVEL CONVERGENCE
IN WEAKLY CAPPED UNSTABLE ENVIRONMENT WITH A MAXIMA IN COVERAGE TIED
TO DIURNAL HEATING. WEAK DEEP LAYER SHEAR SHOULD LIMIT SEVERE
POTENTIAL BUT EFFICIENT RAIN PRODUCING THUNDERSTORMS MOVING SLOW SEEM
POSSIBLE IN A HIGH PWAT ENVIRONMENT (EXCEEDING 1.5 INCHES FRIDAY
NIGHT AND SATURDAY). THIS COULD LEAD TO A LOCALIZED FLOODING THREAT
ESPECIALLY IF STORMS BECOMES NUMEROUS ENOUGH. OTHERWISE NO WEATHER
HAZARDOUS ARE FORESEEN.
MEDIUM RANGE ENSEMBLE GUIDANCE IS IN AGREEMENT SUNDAY INTO EARLY
NEXT WEEK KEEPING THE AMPLIFIED NON-PROGRESSIVE PATTERN. POSITIVE
HEIGHT ANOMALIES WILL STAY TO OUR WEST AND SO TEMPERATURES SHOULD BE
AROUND NORMAL FOR LATE JUNE. WITH MEAN NORTHWESTERLY FLOW...ALBEIT
RELATIVELY WEAK...AND MOIST LOW LEVELS...COULD NOT JUSTIFY LOWER
THAN CLIMO PRECIPITATION PROBABILITIES DURING THIS PERIOD ESPECIALLY
ACROSS THE WESTERN SECTIONS SO HAVE CONTINUED 15-20 POP IN THE WEST.
BRB
&&
.PRELIMINARY POINT TEMPS/POPS...
AMARILLO TX 91 67 90 66 90 / 0 0 0 0 5
BEAVER OK 97 71 98 70 96 / 0 5 0 0 5
BOISE CITY OK 101 67 95 66 93 / 10 10 5 5 10
BORGER TX 96 71 94 70 93 / 0 0 0 0 5
BOYS RANCH TX 97 68 94 66 93 / 0 0 0 0 5
CANYON TX 93 66 90 64 90 / 0 0 0 0 5
CLARENDON TX 91 68 91 67 91 / 0 0 0 0 5
DALHART TX 100 66 93 64 92 / 5 5 0 5 5
GUYMON OK 100 69 97 69 95 / 5 5 0 0 5
HEREFORD TX 93 66 90 63 89 / 0 0 0 0 5
LIPSCOMB TX 95 70 95 70 94 / 0 0 0 0 0
PAMPA TX 91 67 90 67 91 / 0 0 0 0 5
SHAMROCK TX 91 68 93 68 92 / 0 0 0 0 0
WELLINGTON TX 92 69 94 69 93 / 0 0 0 0 0
&&
.AMA WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
OK...NONE.
&&
$$
03/17
AREA FORECAST DISCUSSION
NWS BLACKSBURG VA
733 PM EDT TUE JUN 23 2015
.SYNOPSIS...
A COLD FRONT WILL MOVE INTO AND THROUGH THE AREA
TONIGHT...ACCOMPANIED BY SHOWERS AND STORMS ALONG AND IN ADVANCE OF
THE SYSTEM. DRIER HIGH PRESSURE WILL BUILD INTO THE AREA ON
WEDNESDAY...WITH ONLY ISOLATED SHOWERS OR STORMS EXPECTED LATE IN
THE DAY ACROSS THE SOUTHERN THIRD OF THE REGION. SHOWERS AND STORMS
INCREASE IN NUMBER AGAIN ON THURSDAY...AND CONTINUE INTO THE WEEKEND
WITH A TREND TOWARD COOLER TEMPERATURES BY THE WEEKEND.
&&
.NEAR TERM /THROUGH WEDNESDAY/...
AS OF 710 PM EDT TUESDAY...
GETTING A WEAKENING TREND DESPITE HIGH CAPES THIS EVENING. THINK
CAP IN PLACE HAS LIMITED DEVELOPMENT...BUT CONCERN IS THAT WITH
EVENING THE CAP WEAKENS AND STORMS MAY TAKE OFF. ATTM...KEPT
LIKELY POPS OVER THE WEST AND NORTH...TRYING TO LEAN TOWARD 21Z
HRRR AND RAP...BUT THEN SHOWING MORE SPLIT IN POPS TOWARD LATE
EVENING...WITH ONE AREA MOVING TOWARD TN AND THE OTHER IN THE VA
PIEDMONT.
WILL KEEP THE WATCH GOING...THOUGH SVR THREAT IS ISOLATED ATTM.
PREVIOUS VALID DISCUSSION...
A COLD FRONT EXTENDED FROM WEST CENTRAL PA SOUTHWEST INTO
SOUTHERN INDIANA. SOME ACTIVE CONVECTION WAS ALONG THIS FRONT FROM
CENTRAL OH INTO CENTRAL PA.
BY 02Z/10PM...GUIDANCE IS NOT QUITE AS UNIFORM AS TO THE
POSITIONING OF THE PRECIPITATION. THE HRRR GIVES MORE CREDENCE TO
WESTERLY FLOW LIMITING THE AMOUNT OF COVERAGE OVER SOUTHSIDE
VIRGINIA AND NEIGHBORING PARTS OF NORTH CENTRAL NORTH
CAROLINA...KEEPING ANY LINGERING PRECIPITATION ACROSS THE MOUNTAIN
EMPIRE REGION OF SOUTHWEST VIRGINIA AND THE NORTHERN MOUNTAINS AND
FOOTHILLS OF NC. THE RNK WRF ON THE OTHER HAND OFFERS A SOLUTION
OF GENEROUS COVERAGE NOT ONLY THE AFOREMENTIONED WESTERN
AREAS...BUT SOUTHSIDE VIRGINIA AND NORTH CENTRAL NORTH CAROLINA AS
WELL. OUR FORECAST WILL LEAN MORE TOWARDS THE RNK WRF...BUT NOT AS
ROBUST OF COVERAGE AS THE RNK WRF IN THE SOUTHEAST PART OF THE
REGION. BY MIDNIGHT...ALL MODELS ARE GOOD AGREEMENT THAT LITTLE IF
ANY PRECIPITATION WILL REMAIN ACROSS THE AREA. IF IT DOES...IT
WOULD MOST LIKELY BE IN THE SOUTHEAST PART OF THE AREA...CLOSEST
TO THE COLD FRONT. THE PUSH OF DRIER AIR INTO THE REGION DOES NOT
START UNTIL WEDNESDAY...SO WE EXPECT LOW TEMPERATURES TONIGHT
COMPARABLE TO THOSE OF LAST NIGHT.
THE DAY ONE SEVERE OUTLOOK FROM THE STORM PREDICTION CENTER STILL
OFFERS A SLIGHT RISK OF SEVERE WEATHER ACROSS THE AREA WITH THE
PASSING OF THE MAIN AREA OF PRECIPITATION...WITH DAMAGING WINDS AND
LARGE HAIL BEING THE MAIN CONCERNS. ISOLATED TORNADOES CANNOT BE
RULE OUT.
ON WEDNESDAY...THE COLD FRONT IS EXPECTED TO BE SOUTH OF THE AREA
WITH DRIER HIGH PRESSURE AND SLIGHT COOLER AIR WORKING ITS WAY INTO
THE REGION. HIGHS ARE EXPECTED TO RANGE FROM THE LOW TO MID 80S
ACROSS THE MOUNTAINS AND AROUND 90 TO THE LOWER 90S ACROSS THE
PIEDMONT. PRECIPITATION CHANCE WILL BE LIMITED TO MAINLY ISOLATED
COVERAGE LATE IN THE DAY NEAR THE VA/NC BORDER AND POINTS SOUTH.
THIS AREA WILL BE CLOSEST TO THE DEPARTED COLD FRONT...AND ITS
PROXIMITY AND DAYTIME HEATING WILL ALLOW FOR A FEW SHOWERS AND
STORMS.
&&
.SHORT TERM /WEDNESDAY NIGHT THROUGH FRIDAY/...
AS OF 300 PM EDT TUESDAY...
UPPER PATTERN KEEPS TRACK OF SHORT WAVES FROM THE UPPER MISSISSIPPI
VALLEY INTO THE GREAT LAKES AND OHIO VALLEY THROUGH THURSDAY...THEN
PATTERN BECOMES MUCH MORE AMPLIFIED THURSDAY NIGHT AND FRIDAY WITH A
DEEP TROF OVER THE CENTRAL AND EASTERN UNITED STATES AND A STRONG
RIDGE IN THE WEST.
MODELS SHOWED GOOD AGREEMENT THAT BULK OF DEEP MOISTURE AND LIFT
WILL BE SOUTH OF THE FORECAST AREA ON WEDNESDAY NIGHT. THEN THE NEXT
VORTICITY MAXIMUM...AREA OF LIFT...AND DEEP MOISTURE RETURNS TO THE
AREA AGAIN ON THURSDAY AFTERNOON. THE HIGHEST PROBABILITY OF
PRECIPITATION WILL BE IN THE NORTH AND NORTHWEST COUNTY WARNING
AREA.
GFS IS REASONABLE WITH SURFACE FEATURES WEDNESDAY NIGHT THROUGH
FRIDAY. SLIGHTLY LOWER DEW POINTS ON WEDNESDAY NIGHT WILL RESULT IN
COOLER MINIMUM TEMPERATURES. ON THURSDAY NIGHT LOW PRESSURE OVER THE
MIDWEST WILL TRACK EAST AND OFF THE MID ATLANTIC COAST BY FRIDAY
MORNING...LEAVING A WAVY STATIONARY BOUNDARY ACROSS THE REGION.
&&
.LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/...
AS OF 130 PM EDT TUESDAY...
MODELS CONTINUE TO SUGGEST AN UPPER LOW MAY CUT OFF OVER THE GREAT
LAKES OR OHIO VALLEY AS A SERIES OF SHORT WAVES TRACK DOWN THE WEST
SIDE OF THE UPPER TROF. THE PATTERN WILL REMAIN AMPLIFIED THROUGH
TUESDAY. SO EXPECTING LOWER 500 MB HEIGHTS AND COOLER 850 MB
TEMPERATURES THROUGH THE PERIOD. THE TROUGH DIGS ENOUGH THAT RIGHT
REAR QUADRANT OF THE JET STREAKS ASSOCIATED WITH EACH SHORT WAVE
WILL ENHANCE THE LIFT OVER THE FORECAST AREA ON FRIDAY NIGHT INTO
SATURDAY NIGHT. LIFT WILL ALSO BE AIDED BY 25 TO 30 KNOT EAST 850 MB
WINDS AS A SURFACE LOW TRACKS ACROSS THE TENNESSEE VALLEY AND MID
ATLANTIC REGION THIS WEEKEND.
NCEP FAVORED THE GENERAL TIMING AND POSITION OF THE ECMWF WHICH HAS
ANOTHER FRONTAL SYSTEM AND WAVE OF LOW PRESSURE OVER THE TENNESSEE
VALLEY ON TUESDAY. WIDESPREAD CLOUDS AND PRECIPITATION ON SATURDAY
AND SUNDAY WILL RESULT IN BELOW NORMAL TEMPERATURES. HAVE LOWERED
MAXIMUM TEMPERATURES FOR BOTH DAYS.
&&
.AVIATION /00Z WEDNESDAY THROUGH SUNDAY/...
AS OF 720 PM EDT TUESDAY...
CONVECTION IS WANING ACROSS THE NRV AND SE WV...THOUGH STRONGER
STORMS EXIST ALONG A BROKEN/SCATTERED LINE FROM EKN TO EAST OF
CRW...THEN OVER ERN KY. ATTM...CONFIDENCE IS LOW ON AIRPORTS
RECEIVING PREDOMINANT THUNDER...BUT WILL HAVE VCTS AT ALL SITES
THIS EVENING BEFORE CONVECTION WANES OVERNIGHT.
ISSUE OVERNIGHT WILL BE FOG DEVELOPMENT. MODELS VARY ON SKY COVER
AND THINK SOME LINGERING HIGH CLOUDS WILL LIMIT SOME FOG...BUT
THINK A GOOD CHANCE THAT LWB/BCB WILL GET IFR OR WORSE BY
DAWN...AND POSSIBLY BLF.
WEDNESDAY MORNING...ANY SUB-VFR CONDITIONS WILL IMPROVE TO VFR AS
HIGH PRESSURE BUILDS INTO THE REGION.
EXTENDED AVIATION DISCUSSION...
STORM COVERAGE LOOKS LESS WEDNESDAY AND DEVELOPING MORE OVER THE
TN/NC AREA. THE FRONT WILL RETURN NORTH ACROSS THE AREA ON
THURSDAY AS OUR NEXT SHORTWAVE TROUGH APPROACHES FROM THE
NORTHWEST. LOOK FOR A RETURN OF ISOLATED TO SCATTERED COVERAGE FOR
THE AREA.
THURSDAY NIGHT INTO FRIDAY...THE SHORTWAVE CROSSES THROUGH THE
MID-ATLANTIC STATES BRINGING AN ASSOCIATED COLD FRONT WITH IT.
PRECIPITATION CHANCES WILL INCREASE EVEN MORE...WITH A BETTER
CHANCE OF MORE EXPANSIVE SUB-VFR CONDITIONS.
THROUGH THE WEEKEND...AN UPPER TROUGH STALLS AND DEEPENS OVER THE
MIDWEST WITH A PERSISTENT BAROCLINIC ZONE ACROSS OUR REGION. LOOK
FOR COOLER CONDITIONS...BETTER CHANCES OF SUB-VFR CONDITIONS AND
ADDITIONAL SHOWERS AND STORMS.
&&
.EQUIPMENT...
THE NOAA WEATHER RADIO IN LYNCHBURG...BROADCASTING ON A FREQUENCY
OF 162.550 MHZ...IS WORKING ON THE SECONDARY TRANSMITTER.
TECHNICIANS CONTINUE TO WORK ON THE ISSUE AND HAVE ADVISED THAT
BOTH TRANSMITTERS WONT BE FULLY OPERATIONAL UNTIL THURSDAY.
&&
.RNK WATCHES/WARNINGS/ADVISORIES...
VA...NONE.
NC...NONE.
WV...NONE.
&&
$$
SYNOPSIS...DS
NEAR TERM...DS/WP
SHORT TERM...AMS
LONG TERM...AMS
AVIATION...DS/WP
EQUIPMENT...DS
AREA FORECAST DISCUSSION
NWS BLACKSBURG VA
522 PM EDT MON JUN 22 2015
.SYNOPSIS...
WE WILL CONTINUE TO EXPERIENCE AN ACTIVE WEATHER PATTERN THROUGH
THE REMAINDER OF THE WEEK. THE COMBINATION OF DAYTIME HEATING AND
DISTURBANCES MOVING INTO AND THROUGH THE REGION FROM THE
NORTHWEST...WILL KEEP SHOWERS AND STORMS IN THE FORECAST EACH DAY.
THE PATTERN WILL CONTINUE THIS COMING WEEKEND INTO EARLY NEXT
WEEK...BUT TEMPERATURE TRENDS WILL TURN COOLER.
&&
.NEAR TERM /THROUGH TUESDAY/...
AS OF 522 PM EDT MONDAY...
MADE SOME MINOR ADJUSTMENTS IN POPS AND WEATHER WITH LATEST RADAR
TRENDS AND BLENDED TOWARDS THE RNK WRFARW AND HRRR FOR THIS
EVENING INTO TONIGHT. ALSO MODIFIED TEMPERATURES FOR THIS EVENING
WITH LATEST OBS AND CONVECTION. MORE CHANGES LATER TONIGHT.
AS OF 230 PM EDT MONDAY...
ISOLATED SHOWERS HAVE STARTED TO DEVELOP ALONG THE CREST OF THE BLUE
RIDGE IN NORTH CAROLINA...AND ALSO NORTH OF I-64. AS THE AFTERNOON
CONTINUES...ADDITIONAL HEATING IS EXPECTED TO PROMPT MORE SHOWER AND
THUNDERSTORM DEVELOPMENT. THE BULK OF THE CONVECTION IS EXPECTED TO
BE ACROSS WESTERN INTO SOUTHERN PARTS OF THE AREA...FOLLOWING THE
PATH OF THE REMNANTS OF A THUNDERSTORM COMPLEX THAT DISSIPATED OVER
EASTERN KENTUCKY EARLY THIS MORNING.
OVERNIGHT...THE EVENING CONVECTION IS EXPECTED TO EXIT THE REGION OR
DISSIPATE COMPLETELY BY 10PM-11PM. AFTER THIS TIME...CLOUDS WILL
TREND TO PARTLY CLOUDY TROUGH ROUGHLY 2-3AM TUESDAY. AFTER THIS TIME
FRAME...SOME GUIDANCE HINTS AT A RESURGENCE OF LOW LEVEL MOISTURE
ACROSS WESTERN PARTS OF THE REGION...SO A RETURN TO MOSTLY CLOUDY
SKIES IN AREAS BETWEEN ROUGHLY BLUEFIELD TO LEWISBURG WEST VIRGINIA
IS POSSIBLE. PATCHY LATE NIGHT AND EARLY MORNING FOG WILL BE
POSSIBLE...ESPECIALLY IN THE RIVER AND MOUNTAIN VALLEYS WERE ANY
SUBSTANTIAL PRECIPITATION FALLS THIS AFTERNOON AND EVENING. LOW
TEMPERATURES WILL CONTINUE TO BE ON THE MILD SIDE. READINGS IN THE
MID TO UPPER 60S ARE EXPECTED ACROSS THE MOUNTAINS WITH UPPER 60S TO
AROUND 70 ACROSS THE PIEDMONT.
ON TUESDAY...THE FEATURE THAT IS CURRENTLY PROGRESSING THROUGH THE
GREAT LAKES REGION IS EXPECTED TO BE IMPACTING OUR WEATHER. AS THIS
SYSTEM HEADS SOUTHEAST....OUTFLOW AHEAD OF IT WILL ENTER OUR REGION
TOMORROW AFTERNOON. THIS BOUNDARY AND ASSOCIATED DAYTIME HEATING
WILL HELP GENERATE SHOWERS AND STORMS. THE LATEST DAY 2 CONVECTIVE
OUTLOOK FROM THE STORM PREDICTION CENTER OFFERS A SLIGHT RISK OF
SEVERE WEATHER IN ASSOCIATION WITH THIS THUNDERSTORM ACTIVITY. THE
GREATEST CONCERN WILL BE STRONG TO DAMAGING WINDS WITH SOME OF THE
STORMS. OUR FORECAST WILL REFLECT AN AFTERNOON ARRIVAL...WITH THE
BEST ACTIVITY ACROSS THE NORTHERN THIRD OF THE AREA BY THE LATE
AFTERNOON. PORTIONS OF THE NORTH CAROLINA PIEDMONT AND FOOTHILLS MAY
NEED TO WAIT UNTIL TUESDAY EVENING FOR THE ACTIVITY TO ARRIVE.
TEMPERATURES ON TUESDAY ARE FORECAST TO BE THE HOTTEST OF THE WEEK
THANKS TO INCREASING 850 MB TEMPS OF ABOUT 20 C IN THE WEST AND 24 C
IN THE EAST. HIGHS ARE FORECAST IN THE MID 80S TO AROUND 90 IN THE
MOUNTAINS TO THE MID TO UPPER 90S ACROSS THE PIEDMONT. HEAT INDICIES
WILL BRIEFLY TOUCH THE 100 TO 102 RANGE ROUGHLY ALONG AND EAST OF
A REIDSVILLE NC TO BUCKINGHAM VA LINE LATE IN THE AFTERNOON.
&&
.SHORT TERM /TUESDAY NIGHT THROUGH THURSDAY/...
AS OF 300 PM EDT MONDAY...
NORTHERN STREAM ALOFT REMAINS LINED UP FROM SOUTHWEST CANADA INTO
NEW ENGLAND THROUGH THURSDAY. 500 MB HEIGHTS OVER THE MID ATLANTIC
REGION REMAIN CLOSE TO 590DM WITH A PIECE OF THE UPPER RIDGE STILL
OVER THE SOUTHEAST UNITED STATES. WITH THIS PATTERN...LITTLE CHANGE
IS EXPECTED IN THE WEATHER THROUGH THURSDAY. TEMPERATURES WILL
REMAIN ABOVE NORMAL AND WITH DAILY SCATTERED TO NUMEROUS SHOWERS AND
THUNDERSTORMS. EXTENT...SEVERITY AND TIMING OF THE PRECIPITATION
WILL DEPEND ON THE CONVECTIVE COMPLEXES UPSTREAM OF THE FORECAST
AREA AND WHERE THE RESIDUAL OUTFLOW BOUNDARIES ARE EACH DAY AT THE
TIME OF MAXIMUM HEATING.
THE SURFACE FRONT WILL BE IN THE NORTHERN PART OF THE FORECAST AREA
ON TUESDAY EVENING AND SOUTH OF THE FORECAST AREA ON WEDNESDAY.
THIS FRONT AND RESIDUAL OUTFLOW BOUNDARIES WILL BE THE MAIN TRIGGERS
FOR SHOWERS AND THUNDERSTORMS TUESDAY NIGHT AND WEDNESDAY.
NCEP FAVORS THE ECMWF SOLUTION OF A WAVE DEVELOPING ALONG THE FRONT
OVER THE OHIO VALLEY THEN TRACKING INTO THE MID ATLANTIC REGION ON
THURSDAY. SO THE PROBABILITY OF PRECIPITATION FOR THE AREA WILL
CONTINUE.
&&
.LONG TERM /THURSDAY NIGHT THROUGH MONDAY/...
AS OF 300 PM EDT MONDAY...
UPPER FLOW CHANGES TO A MORE AMPLIFIED PATTERN IN THIS TIME
FRAME...WITH A DEEP TROF OVER THE EASTERN UNITED STATES AND A STRONG
RIDGE IN THE WEST. THIS WILL PROLONG THE CHANCE OF WIDESPREAD
PRECIPITATION THROUGH AT LEAST SUNDAY.
SURFACE LOW PRESSURE DEEPENS OVER THE TENNESSEE VALLEY ON SATURDAY
THEN TRACKS TO OFF THE NEW JERSEY COAST BY LATE SUNDAY. WILL BE
INCREASING THE PROBABILITY OF PRECIPITATION ACROSS THE FORECAST AREA
FOR SATURDAY.
ENOUGH CLOUDS...PRECIPITATION AND LOWER 500 MB HEIGHTS TO BRING
TEMPERATURES BACK DOWN AROUND NORMAL FOR FRIDAY THROUGH SUNDAY.
&&
.AVIATION /21Z MONDAY THROUGH SATURDAY/...
SHOWERS AND THUNDERSTORMS ARE EXPECTED TO DEVELOP THIS AFTERNOON
DURING PEAK HEATING...AND WITHIN THE REGION OF THE LEFTOVER
BOUNDARIES ASSOCIATED WITH A THUNDERSTORM COMPLEX THAT DISSIPATED
OVER EASTERN KENTUCKY EARLY THIS MORNING. THE REMNANTS OF THIS
FEATURE ARE NOW OVER WESTERN PARTS OF THE FORECAST AREA...AND ARE
EXPECTED TO TREND SOUTHEAST AS THE AFTERNOON PROGRESSES. MAINLY
VFR CONDITIONS ARE EXPECTED THIS AFTERNOON. BRIEF SUB-VFR
CONDITIONS ARE POSSIBLE UNDER ANY OF THE HEAVIER PRECIPITATION
CORES THAT FORM. ALSO...WESTERN SECTIONS OF THE AREA STILL HAVE
LCL VALUES IN THE HIGH END OF MVFR RANGE. THERE COULD BE POCKETS
OF STRATO-CU CEILINGS IN THIS AREA DUE SIMPLY TO DAYTIME HEATING.
AFTER ABOUT 20Z/4PM...LCL VALUES SHOULD BE LOW END VFR. THE
ACTIVITY SHOULD WANE OR BE OUT OF THE REGION BY 02-03Z/10-11PM.
OVERNIGHT...MAINLY VFR CONDITIONS ARE EXPECTED. THERE COULD BE A
FEW SPOTS OF MVFR VSBYS IN THE PREFERRED RIVER AND MOUNTAIN
VALLEYS...ESPECIALLY ANY LOCATION THAT RECEIVES A NOTABLE AMOUNT
OF RAINFALL WITH THE ACTIVITY EXPECTED THIS AFTERNOON AND EARLY
EVENING. ALSO...GUIDANCE IS SUGGESTED A RESURGENCE OF MVFR LEVEL
MOISTURE ACROSS WESTERN PARTS OF THE AREA. COULD SEE A MVFR CIG
ALONG AND NEAR A KBLF-KLWB LINE.
ON TUESDAY...ANY SUB-VFR CONDITIONS SHOULD IMPROVE TO VFR BY THE
LATE MORNING. LIMITED CHANCES OF PRECIPITATION EXIST THROUGH THE
END OF THE CURRENT TAF FORECAST PERIOD. ISOLATED SHOWERS OR STORMS
MAY DEVELOP OF MOVE INTO THE KBLF-KLWB AREA OR PARTS WEST AROUND
18Z/2PM.
EXTENDED AVIATION DISCUSSION...
TUESDAY AFTERNOON AND EVENING...A COLD FRONT WILL APPROACH AND
THEN CROSS THE AREA. ANTICIPATE INCREASING CHANCES OF SHOWERS AND
STORMS IN ASSOCIATION WITH THE FRONT. SOME OF THE STORMS MAY
CONTAIN VERY STRONG WIND GUSTS. ALSO...BRIEF SUB-VFR CONDITIONS
ARE EXPECTED UNDER THE HEAVIER CORES.
HIGH PRESSURE WILL BUILD INTO THE AREA FOR WEDNESDAY AND THURSDAY.
HOWEVER...THE FRONT FROM TUESDAY WILL STILL BE NEAR THE SOUTHERN
EDGE OF OUR REGION...AND BECOME STALLED. IN ADDITION...AN UPPER
TROUGH WILL BE POSITIONED ACROSS THE NORTHEAST U.S. THESE FEATURES
WILL CONTINUE TO SERVE AS THE FOCUS FOR ADDITIONAL SHOWERS AND
STORMS.
FRIDAY INTO SATURDAY...A SHORTWAVE TROUGH RIDES SOUTHEAST ALONG
THE ESTABLISHED BAROCLINIC ZONE...AND HELPS TO CARVE OUT AN EVEN
DEEPER EAST COAST TROUGH. LOOK FOR INCREASED COVERAGE OF SHOWERS
AND STORMS WITH A GREATER RANGE OF REAL ESTATE THAT WILL
EXPERIENCE SUB-VFR CIGS AND VSBYS.
&&
.EQUIPMENT...
THE NOAA WEATHER RADIO IN LYNCHBURG...BROADCASTING ON A FREQUENCY
OF 162.550 MHZ...WILL BE PERIODICALLY OFF THE AIR THROUGH TONIGHT.
TECHNICIANS CONTINUE TO WORK ON THE ISSUE AND HAVE ADVISED THAT IT
MAY NOT BE FULLY OPERATIONAL UNTIL TUESDAY.
&&
.RNK WATCHES/WARNINGS/ADVISORIES...
VA...NONE.
NC...NONE.
WV...NONE.
&&
$$
SYNOPSIS...DS
NEAR TERM...DS/KK
SHORT TERM...AMS
LONG TERM...AMS
AVIATION...DS
EQUIPMENT...DS
AREA FORECAST DISCUSSION
NWS BLACKSBURG VA
201 AM EDT MON JUN 22 2015
.SYNOPSIS...
LOW PRESSURE OVER THE UPPER MISSISSIPPI VALLEY WILL MOVE EAST
TONIGHT AND MONDAY AND PUSH A COLD FRONT INTO THE REGION ON
TUESDAY. TEMPERATURES WILL REMAIN ABOVE NORMAL THROUGH THE END OF
THE WEEK WITH A DAILY THREAT OF SHOWERS AND THUNDERSTORMS.
&&
.NEAR TERM /THROUGH TODAY/...
AS OF 1000 PM EDT SUNDAY...
AIRMASS CONTINUES TO STABILIZE LATE THIS EVENING. MAIN AXIS OF
CONVERGENCE SITUATED FROM NE TN INTO THE SRN BLUE RIDGE OF VA. FEW
SHOWERS...SOME THUNDER FROM THE GREENBRIER VALLEY...BUT EXPECT
THESE TO DIE OFF BY MIDNIGHT...SO KEPT SLIGHT CHANCE IN THE NRN
CWA TIL MIDNIGHT.
THINK THE SW CWA WILL KEEP A THREAT OF SHOWERS A LITTLE
LONGER...BUT OVERALL DRY WX EXPECTED AFTER MIDNIGHT...WITH FOG
FORMATION EXPECTED IN THE VALLEYS.
TEMPS WERE RUNNING A LITTLE COOLER OVER THE SW DUE RAIN...BUT
SHOULD STEADY OUT OVERNIGHT...WITH MID 60S WEST TO LOWER 70S EAST.
PREVIOUS VALID DISCUSSION...
UPSTREAM....AREA OF STORMS FROM IND-MT VERNON IL ARE MAY SET THE
STAGE FOR MORE SHOWERS/STORMS TOMORROW. LATEST HRRR AND WRF
FAVORING SOMETHING OVER ERN KY TO OHIO...THOUGH SOME RISING
HEIGHTS/TEMPS ALOFT MAY LIMIT SE ADVANCE.
ON MONDAY...LOW LEVEL FLOW WILL SWITCH TO THE SOUTHWEST AS AN
UPPER RIDGE STARTS BUILDING TO OUR WEST. THIS WILL HAVE THE IMPACT
OF STARTING TO YIELD EVEN HIGHER TEMPERATURES THANKS TO THE START
OF WARM AIR ADVECTION. AFTERNOON HEATING WILL PEAK WITH THE
CROSSING OF AN 850 MB WARM FRONT...WHICH IN TURN WILL HELP ACT AS
A FOCUSING MECHANISM FOR MORE ORGANIZED CONVECTION. HIGH
TEMPERATURES WILL BE A DEGREE OR TWO HIGHER THAN THOSE REALIZED
TODAY WITH MID TO UPPER 80S ACROSS THE MOUNTAINS AND LOW TO NEARLY
MID 90S ACROSS THE PIEDMONT.
&&
.SHORT TERM /TONIGHT THROUGH WEDNESDAY/...
AS OF 300 PM EDT SUNDAY...
ON TUESDAY COLD FRONT WITH GOOD SURFACE CONVERGENCE ENTERS THE
FORECAST AREA FROM THE NORTHWEST. MODELS SHOWED STRONG Q-V FORCING
ALONG WITH MOISTURE POOLING AHEAD OF THE FRONT. IN ADDITION...VERY
WARM AIR MASS WILL RESULT IN A LARGE AMOUNT OF INSTABILITY BY
TUESDAY AFTERNOON AND EVENING. WILL HAVE ONLY LOW PROBABILITY OF
PRECIPITATION ON MONDAY NIGHT BUT WILL INCREASE PROBABILITY BY LATE
TUESDAY AFTERNOON. CLOUD COVER FROM ANY UPSTREAM THUNDERSTORMS IN
THE MORNING MAY LIMIT HEATING EARLY IN THE DAY AND VERY WARM
TEMPERATURES ARE ADVECTING IN AT MID LEVELS WHICH MAY CAP GROWTH OF
STORMS UNTIL LATE TUESDAY. BUFKIT IS FAVORING HE CAP WHICH WOULD
MEAN LESS STORMS FOR ALL BUT THE FAR NORTHERN FORECAST AREA.
GFS POSITION OF THE FRONT IS FAVORED WHICH PLACES THE BOUNDARY JUST
SOUTH OF THE FORECAST AREA ON WEDNESDAY. THIS WILL BE THE FOCUS FOR
SHOWERS AND THUNDERSTORMS ON WEDNESDAY AFTERNOON. WILL HOLD ON TO
CHANCE SHOWERS AND THUNDERSTORMS ACROSS THE SOUTHERN COUNTY WARNING
AREA.
&&
.LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/...
AS OF 300 PM EDT SUNDAY...
500 MB ZONAL FLOW UNTIL THURSDAY THEN BROAD TROUGHING DEVELOPS IN
THE EAST WITH THE ECMWF STILL SHOWING AN MORE AMPLIFIED WAVE OVER
THE OHIO VALLEY SATURDAY NIGHT AND SUNDAY. AT THE SURFACE LOW
PRESSURE AND THE ASSOCIATED COLD FRONT WILL TRACK INTO THE OHIO
VALLEY ON SUNDAY. AT THIS POINT THE MOST LIKELY DAYS THAT WILL HAVE
MORE WIDESPREAD COVERAGE OF SHOWERS AND THUNDERSTORMS LOOK TO BE
SATURDAY AND SUNDAY. TEMPERATURES WILL REMAIN AT OR ABOVE NORMAL
THROUGH THE PERIOD.
&&
.AVIATION /06Z MONDAY THROUGH FRIDAY/...
AS OF 150 AM EDT MONDAY...
NORTHWEST FLOW ALOFT WILL PREVAIL THROUGH THE TAF VALID
PERIOD...AND THE FORECAST WILL BE LARGELY SUBJECT TO TIMING OF
CONVECTIVE COMPLEXES AND/OR ASSOCIATED OUTFLOW BOUNDARIES AND
SUBSEQUENT CONVECTION.
IMMEDIATE CONCERN IS MCS TRANSLATING ESE OUT OF CENTRAL/EASTERN
KY. MODELS SEEM TO BE IN GOOD AGREEMENT WITH CURRENT
SATELLITE/RADAR TRENDS THAT THIS ACTIVITY WILL DRIFT INTO SOUTHERN
WV/EASTERN TN/SOUTHWESTERN VA TOWARD 12Z AND DISSIPATE...THEN
REDEVELOP DURING THE LATE MORNING/EARLY AFTERNOON IN THE
LWB/BLF/BCB AREA DRIFTING EAST TOWARD THE PIEDMONT BY MID-LATE
AFTERNOON. THUS...HAVE INTRODUCED VCTS FOR ALL SITES...STARTING IN
THE WEST AROUND 17Z AND ACROSS THE PIEDMONT IN THE 20-21Z TIME
FRAME. AS WAS THE CASE ON SUNDAY...HOWEVER...SUCH TIMING IS
SUBJECT TO CONSIDERABLE ADJUSTMENT BASED ON DEVELOPMENT ON
RESIDUAL OUTFLOW BOUNDARIES AND AREAS OF DIFFERENTIAL HEATING FROM
MORNING CLOUD COVER. AS WAS THE CASE YESTERDAY...THERE REMAINS THE
POTENTIAL FOR A FEW STRONG TO SEVERE THUNDERSTORMS WITH GUSTY
WINDS BEING THE MAIN THREAT. IT WOULD APPEAR BASED ON THE BEST
LINEUP OF OUTFLOW BOUNDARIES AND HEATING...THAT THE PIEDMONT WOULD
BE THE PRIME AREA TODAY FOR CONVECTION. BRIEF PERIODS OF MVFR
CIGS/VSBYS WILL ACCOMPANY CONVECTION.
OUTSIDE THE CONVECTION...GENERALLY LOOKING AT VFR CONDITIONS WITH
THE EXCEPTION OF MORNING FOG. GIVEN EXTENSIVE MID/HIGH CLOUD COVER
FROM UPSTREAM CONVECTION AND WARM TEMPERATURES...THIS DOES NOT
APPEAR TO BE A SIGNIFICANT ISSUE. HAVE BACKED OFF THE DENSE FOG AT
LWB A TAD AS THEY STILL HAVE A 4-DEGREE SPREAD AND CLOUD COVER.
RESIDUAL SHOWERS AND OUTFLOW WINDS FROM UPSTREAM CONVECTION MAY
REACH BLF/LWB BEFORE DAYBREAK AS WELL...FURTHER REDUCING THE
POTENTIAL FOR FOG.
WINDS OUTSIDE THUNDERSTORMS WILL BE SW-WNW 5-7KTS THROUGH MUCH OF
THE PERIOD...NEAR CALM AT NIGHT AT BCB/LWB.
MEDIUM CONFIDENCE IN CIGS THROUGH THE TAF VALID PERIOD.
MEDIUM TO HIGH CONFIDENCE IN VSBYS THROUGH THE TAF VALID PERIOD.
MEDIUM TO HIGH CONFIDENCE IN WIND SPD/DIR THROUGH THE TAF VALID
PERIOD.
MEDIUM CONFIDENCE IN TSRA POTENTIAL TODAY.
EXTENDED AVIATION DISCUSSION...
BUILDING HEIGHTS WILL INCREASE THE CAP STRENGTH OVERHEAD TUESDAY
AND HELP LIMIT ADDITIONAL CONVECTION. HOWEVER...A LINGERING
BOUNDARY OVER THE AREA MAY PROVIDE THE FOCUS NEEDED FOR SOME
ADDITIONAL SHOWERS AND STORMS.
COVERAGE WILL INCREASE AGAIN LATE TUESDAY AFTERNOON AND THE
TUESDAY NIGHT AS A COLD FRONT MOVES THROUGH THE AREA. THIS
FEATURE WILL STALL ACROSS THE AREA AND ACT AS A STRONGER FOCUS FOR
ADDITIONAL SHOWERS AND STORMS THROUGH FRIDAY...ESPECIALLY AS
UPSTREAM CONVECTION RIDES SOUTHEAST ALONG THE BOUNDARY.
DURING THIS PERIOD...THERE WILL BE THE POTENTIAL FOR THE TYPICAL
LATE NIGHT/EARLY MORNING DEVELOPMENT OF MOUNTAIN AND RIVER VALLEY
FOG...ESPECIALLY IN AREAS THAT WOULD HAVE RECEIVED PRECIPITATION
THE PREVIOUS DAY.
&&
.RNK WATCHES/WARNINGS/ADVISORIES...
VA...NONE.
NC...NONE.
WV...NONE.
&&
$$
SYNOPSIS...AMS
NEAR TERM...DS/WP
SHORT TERM...AMS
LONG TERM...AMS
AVIATION...DS/RAB/WP
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
620 PM CDT TUE JUN 23 2015
.SHORT TERM...(THIS EVENING THROUGH WEDNESDAY)
ISSUED AT 341 PM CDT TUE JUN 23 2015
CURRENTLY AS OF 20Z...WATER VAPOR LOOP AND RAP 500MB HEIGHT ANALYSIS
SHOWED SUBTROPICAL RIDGING ENCOMPASSING THE SOUTHERN U.S.. WHILE A
WEST-NORTHWEST FLOW RUNS FROM THE PACIFIC NORTHWEST INTO THE MID-
ATLANTIC. THE TWO MAIN SHORTWAVES OF NOTE WERE OVER THE SIOUX FALLS
AREA AND SOUTHERN BRITISH COLUMBIA. THE ONE IN SIOUX FALLS ALONG
WITH A WIDE AREA OF LOW TO MID LEVEL FRONTOGENESIS WAS HELPING TO
PRODUCE PLENTY OF ALTOSTRATUS FROM SOUTH DAKOTA/NEBRASKA EAST INTO
THE SOUTHERN PORTION OF THE FORECAST AREA. AIRMASS HAS BEEN TOO DRY
TO SUPPORT ANY PRECIPITATION DESPITE SEEING ECHOES ON RADAR...AS
REFLECTED BY THE 12Z MPX SOUNDING WITH A 700MB DEWPOINT DEPRESSION
OF 40C. ONLY A VERY FEW SITES HAVE REPORTED SPRINKLES. MAIN SURFACE
FRONTAL BOUNDARY ASSOCIATED WITH THE FRONTOGENESIS WAS WELL TO THE
SOUTH...SITUATED JUST SOUTH OF I-70 AND WAS VERY SLOWLY LIFTING
NORTH TODAY. THAT NORTHWARD PROGRESS HAS BEEN HELD BACK BY A
PERSISTENT COMPLEX OF CONVECTION FROM SOUTHEAST NEBRASKA INTO THE
KANSAS CITY AREA. SUNSHINE TODAY COMBINED WITH 850MB TEMPS AROUND
10C HAS RESULTED IN HIGHS MOSTLY IN THE 70S. MUCH LOWER DEWPOINTS
TODAY THAN YESTERDAY WITH MIXING AND DRY AIR RESULTING IN READINGS
OF 45 TO 55F.
LOOK FOR A CONTINUATION OF QUIET CONDITIONS TONIGHT ACROSS THE
FORECAST AREA AS THE AREA OF HIGH PRESSURE HELPING TO PROVIDE THE
DRY CONDITIONS ONLY DRIFTS OFF TO THE SOUTHEAST. WE WILL HAVE TO
DEAL WITH THE SOME HIGHER BASED FRONTOGENESIS...YIELDING SOME
ALTOSTRATUS AS WE ARE SEEING TODAY. THESE CLOUDS SHOULD HELP TO
PRECLUDE FOG FORMATION...AND ALSO KEEP TEMPERATURES FROM FALLING
BELOW THE MID 50S.
THE MORE INTERESTING PART OF THE SHORT TERM IS FOR WEDNESDAY. MODELS
CONTINUE TO ADVERTISE THAT THE FRONTAL BOUNDARY IN KANSAS WILL LIFT
NORTHWARD OVER THE NEXT 24 HOURS...IN RESPONSE TO A MONSOONAL
SHORTWAVE COMING OUT OF COLORADO AND ROTATING AROUND THE SOUTHERN
U.S. SUBTROPICAL RIDGE. AS THIS OCCURS WITH THE NOCTURNAL LOW LEVEL
JET...MODELS ARE ADVERTISING AT LEAST CONVECTION IF NOT AN MCS TO
DEVELOP OVER EASTERN NEBRASKA AND WESTERN IOWA LATE TONIGHT. CORFIDI
VECTORS WOULD TAKE THIS MCS INTO NORTHERN MO WEDNESDAY MORNING...
HOLDING THE FRONT BACK. HOWEVER...SOME GUIDANCE LIKE THE 23.12Z
GFS/NAM WANT TO KEEP MOVING THE FRONT NORTH INTO THE AFTERNOON...
SPREADING EITHER PREVIOUS OR NEW CONVECTION INTO NORTHEAST IA AND
SOUTHWEST WI. BELIEVE THIS IS GOING TO BE TOUGH AS CLOUD DEBRIS
LIMITS DAYTIME MIXING...AND CONVECTIVE OUTFLOW HOLDS THE BOUNDARY
BACK. MORE LIKELY...WHEN NEW CONVECTION FIRES IT WILL BE FARTHER
SOUTH CLOSER TO THE FRONT...WHICH SHOULD BE HUNG UP NEAR THE MO/IA
BORDER BY 00Z THU. THE 23.12Z ECMWF REMAINS THE FARTHEST SOUTH MODEL
WITH THE FRONT AND CONVECTION...AND SEEMS MOST REASONABLE GIVEN
EXPECTED CONVECTION TRACKS. THEREFORE...PRECIPITATION CHANCES ARE
HIGHEST IN NORTHEAST IA BUT STILL ONLY AS MUCH AS 50 PERCENT BY LATE
IN THE DAY GIVEN ANTICIPATION FOR MOST CONVECTION TO STAY SOUTH.
GIVEN THE MAJORITY OF CAPE TO STAY WELL SOUTH OF THE AREA...THE
SLIGHT RISK ON SPCS DAY 2 OUTLOOK WAS SHIFTED MOSTLY OUT OF THE
FORECAST AREA. ITS WORTH NOTING THAT MODELS...OUTSIDE THE 23.12Z
ECMWF...HAVE REALLY STRUGGLED WITH THE ONGOING CONVECTION NORTH OF
THE FRONT IN THE KANSAS CITY AREA.
THERE IS ALSO SOME CONCERN FOR SHOWERS AND STORMS TO FIRE NORTH OF
HIGHWAY 29 WEDNESDAY AFTERNOON...RELATED TO THE SHORTWAVE IN BRITISH
COLUMBIA HEADING INTO NORTHERN PORTIONS OF MN OR WI. THE ECMWF IS
SLOWEST WITH THE SHORTWAVE AND THEREFORE IS DRY...WHEREAS THE GFS
AND NAM ARE FASTER AND HAVE PRECIP. THE GFS/NAM ALSO HAVE HIGHER
SURFACE DEWPOINTS WHICH SEEM TOO HIGH. THEREFORE...HAVE ONLY KEPT A
20 PERCENT CHANCE IN TAYLOR COUNTY LATE IN THE DAY.
WITH 850MB TEMPS IN THE 12-14C RANGE AND SOME SUN LIKELY FOR AT
LEAST THE MORNING HOURS...HIGHS SHOULD PUSH INTO THE MID 70S TO LOW
80S...WARMEST TO THE NORTH WHERE LONGER PERIOD OF SUN IS EXPECTED.
.LONG TERM...(WEDNESDAY NIGHT THROUGH TUESDAY)
ISSUED AT 341 PM CDT TUE JUN 23 2015
23.12Z ECMWF/GFS/CANADIAN MAINTAIN THE SAME LONG WAVE PATTERN THEY
HAVE BEEN SHOWING THE PAST SEVERAL DAYS...WITH STRONG SUBTROPICAL
RIDGING SHIFTING AND BUILDING OVER THE WESTERN U.S. ON
THURSDAY...CAUSING FAIRLY DEEP TROUGHING FOR THIS TIME OF YEAR OVER
THE EASTERN U.S.. THIS SHIFT IS IN RESPONSE TO THE MADDEN JULIAN
OSCILLATION GOING INTO AN ANOMALOUSLY STRONG PHASE 6. WHAT THIS
MEANS FOR THE FORECAST AREA IS TEMPERATURES TO HOLD AT OR NEAR
SEASONABLE NORMALS...WITH PERHAPS A SLOW WARMUP LATE IN THE WEEKEND
INTO EARLY NEXT WEEK. ANY GULF OF MEXICO RETURN OF MOISTURE SHOULD
GET SHUTOFF WITH MOISTURE SOURCES MOSTLY TURNING TO
EVAPOTRANSPIRATION AND WHAT SYSTEMS CAN BRING OFF THE PACIFIC DOWN
THE RIDGE.
THE MAIN FOCUS FOR PRECIPITATION REMAINS WEDNESDAY NIGHT.
HOWEVER...SIMILAR TO WEDNESDAY...HOW FAR NORTH THE WARM FRONT NEAR
THE IA/MO BORDER AT 00Z THU REALLY DETERMINES THE CONVECTION
CHANCES. CURRENT THINKING LIES ALONG THE MORE PREFERRED ECMWF VERSUS
THE BIASED NORTH GFS/NAM/SREF/CANADIAN...WHICH SUGGESTS ANOTHER MCS
FORMING OVER CENTRAL IOWA WEDNESDAY EVENING...MARCHING LIKELY
SOUTHEASTWARD FOLLOWING CORFIDI VECTORS. THIS IS IN LINE WITH THE
HIGHEST SPC DAY 2 OUTLOOK PROBABILITIES. THE NORTHERN PART OF THIS
MCS COULD CLIP OUR FAR SOUTH...THUS HAVE THE HIGHEST 50-60 PERCENT
CHANCES THERE FOR THE EVENING. TRIMMED CHANCES BACK FARTHER NORTH
AND AREAS NORTH OF U.S. HIGHWAY 18 MAY END UP DRY. THE LONE
EXCEPTION WOULD BE NORTH OF HIGHWAY 29...CLOSER TO THAT SHORTWAVE
TROUGH MARCHING ACROSS MN AND NORTHERN WI. PRECIPITATION SHOULD
DIMINISH WEST TO EAST DURING THE OVERNIGHT HOURS AS THE MCS AND
SHORTWAVE TROUGHS MOVE FURTHER AWAY FROM THE AREA.
FOR THURSDAY AND FRIDAY...THE 23.12Z GFS AND TO A LESSER EXTENT THE
NAM WANT TO FIRE UP SOME DIURNAL SHOWERS AND STORMS...ASSOCIATED
WITH WEAK SHORTWAVES DROPPING THROUGH THE NORTHWEST FLOW. THE 23.12Z
ECMWF SHOWS THESE SAME SHORTWAVES BUT IS DRY. MUCH OF THE DIFFERENCE
RELATES TO BOUNDARY LAYER MOISTURE AND ITS IMPACT TO CAPE. AT BOTH
00Z FRI AND 00Z SAT...THE GFS IS NEARLY 10F HIGHER ON SURFACE
DEWPOINTS TO THE ECMWF. THINKING THE ECMWF IS MORE CORRECT AND THUS
HAVE ONLY 20-30 PERCENT CHANCES AT MOST...HIGHEST IN WESTERN AREAS.
SATURDAY LOOKS DRY WITH HIGH PRESSURE IN PLACE...BUT THEN THERE IS
AN ISSUE WITH SUNDAY INTO MONDAY WITH MODELS TIMING A STRONGER
SHORTWAVE TROUGH DROPPING THROUGH THE NORTHWEST FLOW. THE 23.12Z
ECMWF IS FASTEST AND SPREADS SOME CONVECTION ACROSS THE AREA ON
SUNDAY...WHEREAS THE 23.12Z CANADIAN/GFS WAIT UNTIL EITHER LATER
SUNDAY NIGHT OR MONDAY. GIVEN THE SPREAD...HAVE KEPT A 20-40 PERCENT
CHANCE FOR ALL 3 12 HOUR TIME PERIOD. NEEDLESS TO SAY A GOOD PORTION
CAN PROBABLY BE DRIED OUT IN LATER FORECASTS ONCE THE TIMING GETS
RESOLVED. ANOTHER NORTHWEST FLOW WAVE IS PROGGED FOR TUESDAY...
RESULTING IN MORE CHANCES OF PRECIPITATION.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z WEDNESDAY EVENING)
ISSUED AT 620 PM CDT TUE JUN 23 2015
THIS LOOKS TO BE A QUIET PERIOD OF VFR WEATHER...BUT THERE IS SOME
UNCERTAINTY IN THIS BY LATE WEDNESDAY AFTERNOON. A COLD FRONT IS
OVER SOUTHERN KANSAS AND MISSOURI LATE THIS AFTERNOON. THE 23.18Z
NAM...23.12Z HI-RES ARW AND 23.19Z HRRR SHOW THAT AS THE LOW
LEVEL JET INCREASES THIS EVENING AND IMPINGES ON THE
FRONT...ANOTHER COMPLEX OF STORMS SHOULD DEVELOP ALONG OR SOUTH OF
INTERSTATE 80 AND THEN MOVE OFF TO THE SOUTHEAST AND NOT IMPACT
THE LOCAL AREA. HOWEVER...GIVEN THE CURRENT LOCATION OF THE
FRONT...THE ACTIVITY THAT DEVELOPS OVERNIGHT HAS THE POTENTIAL TO
BE EVEN FARTHER SOUTH. THE FRONT SHOULD MAKE SOME NORTHWARD
PROGRESS WEDNESDAY ONCE THE OVERNIGHT CONVECTION MOVES OFF...BUT
THE QUESTION BECOMES HOW FAR NORTH IT WILL GET. THE NAM AND ARW
WOULD SUGGEST IT COULD GET INTO CENTRAL IOWA WITH THE NEXT ROUND
OF CONVECTION FORMING LATE WEDNESDAY AFTERNOON OVER NORTHERN IOWA.
ONCE AGAIN...THE MODELS MAY BE TOO FAR NORTH WITH THE FRONT AND
THE CONVECTION WEDNESDAY MAY BE WELL TO THE SOUTH. BELIEVE THAT
THE CONVECTION STAYING WELL TO THE SOUTH IS THE MORE LIKELY
OUTCOME...WHICH WAS THE TREND FROM THE PREVIOUS FORECASTS AND HAVE
CONTINUED THAT TREND.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...AJ
LONG TERM...AJ
AVIATION...04
AREA FORECAST DISCUSSION
NWS MILWAUKEE/SULLIVAN WI
351 PM CDT MON JUN 22 2015
.SHORT TERM...
.TONIGHT AND TUESDAY...FORECAST CONFIDENCE IS MEDIUM.
SWLY WIND GUSTS MAINLY IN THE 30 MPH RANGE WILL CONTINUE UNTIL THE
MIXING CEASES TOWARD EVENING. OTHERWISE CHANCES OF TSTORMS REMAIN
FOR THE LATE AFTERNOON AND EARLY EVENING AS CAPE BUILDS AND CIN
WEAKENS ALONG THE COLD FRONT OVER WRN WI. OVERALL THOUGH BELIEVE
SOME CIN WILL REMAIN OVER THE CWA AND LIMIT TSTORM POTENTIAL WITH
ONLY LOW CHANCES OF SVR TSTORMS. THE LATEST HRRR MODEL ONLY
INDICATES MINOR DEVELOPMENT OVER SRN WI BUT MORE ROBUST DEVELOPMENT
OVER ERN IA AND NRN IL. COLD AND DRY AIR ADVECTION TO THEN PREVAIL
LATER TONIGHT INTO TUE AM. HIGH PRESSURE TO BUILD INTO WI LATE ON
TUE. A PLEASANT SUMMER DAY IS EXPECTED WITH LOW RELATIVE HUMIDITY.
LAKE BREEZE DEVELOPMENT IS EXPECTED IN THE AFTERNOON.
.WEDNESDAY AND THURSDAY...FORECAST CONFIDENCE IS MEDIUM.
A SHORTWAVE EMBEDDED IN NW FLOW ALOFT IN CONJUNCTION WITH THE EXIT
REGION OF A ZONAL JET STREAK WILL PROVIDE UPPER LEVEL SUPPORT FOR
SHOWERS AND THUNDERSTORMS DURING THIS PERIOD...ESPECIALLY
WEDNESDAY AFTERNOON THROUGH THURSDAY MORNING. CLOSER TO THE
SURFACE...LOW PRESSURE OVER THE CENTRAL PLAINS WILL MOVE NORTHWEST
INTO THE REGION...REACHING SOUTHERN WISCONSIN SOMETIME WEDNESDAY
EVENING OR THURSDAY MORNING. THE LOW TO MID LEVELS BECOME
SATURATED JUST THE ARRIVAL OF THE LOW...SETTING THE STAGE FOR
SHOWERS. MODEST INSTABILITY...ALONG WITH MODERATE TO STRONG
SHEAR..WILL SUPPORT SHOWERS AND THUNDERSTORMS FROM WEDNESDAY
AFTERNOON THROUGH THURSDAY. THERE IS SOME DISAGREEMENT AMONG THE
MODELS REGARDING THE TIMING AND INTENSITY OF THIS SYSTEM. GFS/GEM
COME IN WITH A RELATIVELY DEEP LOW AND PRECIP BULLSEYE EARLY
THURSDAY MORNING WHILE THE ECMWF BRINGS A MORE MEAGER LOW SOUTH OF
THE FORECAST AREA WITH LESS PRECIP FOR SOUTHERN WISCONSIN.
.LONG TERM...
FRIDAY AND SATURDAY...FORECAST CONFIDENCE IS MEDIUM.
AFTER THE PREVIOUSLY MENTIONED SHORTWAVE SWINGS THROUGH THE
AREA...SE WI WILL BE ENTRENCHED IN NW FLOW ALOFT WITH LITTLE
SUPPORT FOR UPWARD MOTION. LATEST GFS CONTINUES TO PRODUCE A FEW
ROUNDS OF VERY LIGHT QPF WHILE THE EURO REMAINS DRY. WILL BE
KEEPING SOME PRECIP CHANCES TO ACCOUNT FOR GFS QPF...BUT AT THIS
POINT HAVE LOW CONFIDENCE FOR PRECIP.
.SUNDAY AND MONDAY...FORECAST CONFIDENCE IS MEDIUM.
THE ECMWF AND GFS ARE IN GOOD AGREEMENT WITH THE INTENSITY AND
TIMING OF AN UPPER-LEVEL SHORTWAVE TROF/SURFACE LOW PRESSURE SYSTEM
THAT WILL MOVE THROUGH SOUTHERN WISCONSIN DURING THIS PERIOD. GIVEN
MODEST THE INSTABILITY IN BOTH MODELS...THERE IS A SHOT AT SHOWERS
AND THUNDERSTORMS BEGINNING ON SUNDAY AFTERNOON AND CONTINUING INTO
MONDAY MORNING.
&&
.AVIATION/00Z TAFS/...
GUSTY SWLY WINDS WILL PREVAIL INTO THE EARLY EVENING BEFORE
DIMINISHING WITH SUNSET. ALSO BROKEN STRATOCUMULUS FROM 1.5-3.0
KFT WILL OVERSPREAD SOUTH CENTRAL WI AHEAD OF AN APPROACHING COLD
FRONT LATE THIS AFTERNOON AND EARLY EVENING. THE STRATOCUMULUS MAY
MOVE INTO SE WI AS WELL BUT CONFIDENCE IS LOW. OTHERWISE...CHANCES
OF SHOWERS AND TSTORMS ARE POSSIBLE WITH THE COLD FRONT PASSAGE.
VFR CONDITIONS AND CLEARING SKIES ARE EXPECTED LATE THIS EVENING.
VFR CONDITIONS TO PREVAIL ON TUE.
&&
.MARINE...
BREEZY SWLY WINDS WITH WIND GUSTS APPROACHING GALE FORCE
WILL CONTINUE INTO THE EARLY EVENING BEFORE WEAKENING. A SMALL CRAFT
ADVISORY IS IN EFFECT UNTIL 10 PM.
&&
.BEACHES...
A BEACH HAZARD STATEMENT WILL REMAIN IN EFFECT FOR THE
BEACHES OF SHEBOYGAN COUNTY DUE TO BREEZY SOUTH TO SOUTHEAST WINDS.
THE WINDS WILL EVENTUALLY VEER SOUTHWEST BUT THIS MAY NOT OCCUR
UNTIL THE EARLY EVENING.
.MKX WATCHES/WARNINGS/ADVISORIES...
WI...BEACH HAZARDS STATEMENT UNTIL 10 PM CDT THIS EVENING FOR WIZ052.
LM...SMALL CRAFT ADVISORY UNTIL 10 PM CDT THIS EVENING FOR LMZ643>646.
&&
$$
TONIGHT/TUESDAY AND AVIATION/MARINE...GEHRING
TUESDAY NIGHT THROUGH MONDAY...BSH
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
247 PM CDT MON JUN 22 2015
.SHORT TERM...(THIS EVENING THROUGH TUESDAY)
ISSUED AT 247 PM CDT MON JUN 22 2015
CURRENTLY AS OF 19Z...WATER VAPOR LOOP AND RAP 500MB HEIGHT ANALYSIS
SHOWED SUBTROPICAL RIDGING ENCOMPASSING MUCH OF THE SOUTHERN U.S.
WHILE MAINLY ZONAL FLOW WAS OVER THE NORTHERN U.S.. WITHIN THIS
FLOW...A POTENT SHORTWAVE TROUGH WAS CROSSING NORTHERN MN WHILE THE
SHORTWAVE THAT FORMED FROM THIS MORNINGS CONVECTION WAS OVER LOWER
MI. SUBSIDENCE IN THE WAKE OF THE CONVECTIVE SHORTWAVE...COMBINED
WITH CLEARING NOT OCCURRING UNTIL EARLY THIS AFTERNOON...HAS HELPED
TO PREVENT ADDITIONAL CONVECTION FROM FIRING. RAP DEPICTING
ANYWHERE FROM 50 TO 200 J/KG OF MLCIN. THIS WAS DESPITE A
COLD FRONT TRACKING THROUGH THE FORECAST AREA ASSOCIATED WITH THE
POTENT TROUGH. THAT FRONT WAS NOW LOCATED FROM NORTHEAST WISCONSIN
THROUGH SOUTHWEST IOWA. MUCH DRIER AIR FLOWING IN BEHIND THE
FRONT...NOTED BY PRECIPITABLE WATER IN THE 2 INCH RANGE OVER
SOUTHEAST IOWA TO 0.5-0.75 INCHES IN THE DAKOTAS AND CENTRAL MN.
SOME STRATOCUMULUS DEVELOPMENT HAS OCCURRED IMMEDIATELY BEHIND THE
FRONT AS WELL...ASSOCIATED WITH MOISTURE TRAPPED IN THE COLD
FRONTAL INVERSION. TEMPERATURES ARE MOSTLY IN THE 70S TO LOWER 80S.
MUCH QUIETER SHORT TERM PERIOD EXPECTED. THE POTENT SHORTWAVE TROUGH
OVER MN WILL CONTINUE ITS MARCH QUICKLY EASTWARD TOWARDS EASTERN
ONTARIO BY 12Z TUE. EXPECT SUBSIDENCE AND DRYING TO SPREAD INTO THE
FORECAST AREA THIS EVENING BEHIND THE TROUGHS COLD FRONTAL
PASSAGE. THAT FRONT SHOULD CLEAR THE AREA BY 00Z...TAKING ANY
CONVECTION CHANCES WITH IT...WHICH ARE MINIMAL DUE TO ALL OF THE
MLCIN...LACK OF CONVERGENCE ALONG THE FRONT AND BEING IN THE RIGHT
EXIT REGION OF A 100KT JET CORE TRACKING INTO NORTHERN WI. MAY STILL
HAVE TO DEAL WITH SOME POST-FRONTAL STRATOCUMULUS...BUT THAT TOO
SHOULD CLEAR BY 06Z AS DRIER AIR CONTINUES TO WORK IN. ALL OF
TUESDAY LOOKS TO REMAIN DRY...THOUGH SOME MID CLOUDS SHOULD SPREAD
ACROSS THE AREA DURING THE DAY ASSOCIATED WITH MID LEVEL
FRONTOGENESIS.
WINDS WILL GRADUALLY DIMINISH DURING THE NIGHT AS HIGH PRESSURE
BUILDS IN. COULD SEE SOME PATCHY FOG DEVELOP IN OUR TYPICAL COLD
SPOTS AS A RESULT WITH WINDS DECOUPLING THERE AND RECENT RAIN...BUT
ENOUGH WIND LOOKS TO CONTINUE TO PREVENT FOG ELSEWHERE. LOWS IN THE
50S TO LOW 60S PER GUIDANCE SEEMS REASONABLE. 925MB TEMPS OF
16-18C ON TUESDAY SHOULD RESULT IN HIGHS IN THE 70S WITH A FEW LOW
80S POSSIBLE IN RIVER VALLEYS.
.LONG TERM...(TUESDAY NIGHT THROUGH MONDAY)
ISSUED AT 247 PM CDT MON JUN 22 2015
MUCH OF THE LONG TERM PERIOD THE FORECAST AREA RESIDES IN NORTHWEST
FLOW ALOFT...WHICH BECOMES EVEN MORE NORTHERLY FOR THE WEEKEND INTO
EARLY NEXT WEEK AS ANAMOULSY STRONG SUBTROPICAL RIDGING BUILDS OVER
THE WESTERN U.S.. THIS TYPE OF PATTERN WILL HOLD TEMPERATURES AT OR
BELOW SEASONABLE NORMS.
ON THE PRECIPITATION SIDE OF THINGS...A COUPLE OF TIME PERIODS OF
CONCERN...
1. WEDNESDAY. A SHORTWAVE COMING OUT OF NEBRASKA AND SOUTH DAKOTA
LOOKS TO TRACK INTO ILLINOIS. THIS SHORTWAVE WILL HELP TO PULL THE
CURRENT FRONTAL BOUNDARY...WHICH STALLS NEAR I-70 ON TUESDAY...BACK
NORTHWARD. THE QUESTION IS HOW FAR NORTH. THE ECMWF IS FARTHEST
SOUTH...HOLDING IT OVER NORTHERN MO...WHILE THE GFS...NAM AND
CANADIAN PULL IT AT LEAST TO I-80. SHOWERS AND THUNDERSTORMS...
ISENTROPICALLY AND FRONTOGENETICALLY DRIVEN ON ITS NORTH SIDE...MAY
TRY TO MAKE A RUN TOWARDS THE FORECAST AREA. HOWEVER...CONVECTIVE
OUTFLOWS FROM THE PRECIPITATION MAY TEND TO HOLD THE FRONT BACK.
ADDITIONALLY...THE FRONT IS PARALLEL TO THE UPPER FLOW WHICH ISNT
GOOD FOR LIFTING IT NORTHWARD. THEREFORE...HAVE TRENDED
PRECIPITATION CHANCES DOWN WITH THE HIGHEST CHANCES IN NORTHEAST
IOWA CLOSEST TO THE FRONTAL BOUNDARY.
2. WEDNESDAY NIGHT INTO THURSDAY. ANOTHER SERIES OF SHORTWAVES
ARE PROGGED TO COME OUT OF THE DAKOTAS THROUGH THE FORECAST AREA.
HOW MUCH PRECIPITATION THEY PRODUCE WILL DEPEND ON HOW FAR NORTH
THAT WARM FRONTAL BOUNDARY GETS ON WEDNESDAY. LIKE THE MODEL SPREAD
ON WEDNESDAY...THE ECMWF REMAINS THE FARTHEST SOUTH WHILE THE NAM
AND ESPECIALLY THE GFS AND CANADIAN ARE FARTHER NORTH. THE LATTER 3
MODELS PRODUCE MUCH MORE CONVECTION AND PRECIPITATION FOR US WHILE
THE ECMWF IS NEARLY DRY WITH ITS CONVECTION SOUTH OF THE FORECAST
AREA. GIVEN THE NAM/GFS/CANADIAN BIAS OVERALL THIS YEAR TO BE TOO
FAR NORTH...THE NORTHWEST FLOW PATTERN AND CONVECTIVE
OUTFLOWS HOLDING UP THE FRONT...FEEL A MORE SOUTHERN TRACK OF THE
ECMWF IS MORE LIKELY TO OCCUR. THEREFORE...PRECIPITATION CHANCES FOR
THE MOST PART ARE IN THE 20-50 RANGE. HARD TO GET TOO EXCITED ABOUT
ANY SEVERE CHANCES GIVEN THIS SPREAD IN CONVECTION LOCATION AS
WELL.
3. BEYOND THURSDAY THROUGH EARLY NEXT WEEK. MODELS ARE DRIVING
MULTIPLE SHORTWAVES DOWN ACROSS THE FORECAST AREA. PROBLEM IS THE
MOISTURE AS THE MAIN FRONTAL BOUNDARY AFTER THE SHORTWAVES PASS ON
THURSDAY GETS SHUNTED DOWN TO THE GULF COAST. NEW 22.12Z ECMWF
REALLY HAS BACKED OFF ON PRECIPITATION AND DEPICTS MONDAY AS THE
ONLY TIME PERIOD OF SEEING SOME PRECIPITATION. MEANWHILE...THE
22.12Z GFS/CANADIAN BOTH WANT TO KEEP THE AREA GETTING HIT BY
SPORADIC SHOWERS/STORMS WITH THE SHORTWAVES. IT APPEARS THESE MODELS
MAY BE PRODUCING TOO MUCH EVAPOTRANSPIRATION TO BOOST UP BOUNDARY
LAYER MOISTURE. THEREFORE...CHANCES OF PRECIPITATION FOR THE REST OF
THE FORECAST HAVE BEEN TRENDED DOWNWARD. LATER FORECASTS SHOULD BE
ABLE TO GIVE SOME DRY PERIODS.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON)
ISSUED AT 1210 PM CDT MON JUN 22 2015
CONVECTIVE COMPLEX QUICKLY MOVED INTO EASTERN WI LATE THIS
MORNING...WITH SUBSIDENCE/DRYING IN ITS WAKE CLEARING OUT MUCH OF
THE LOW/MIDDLE CLOUDS. RESIDUAL LOWER LEVEL MOISTURE WITH THE RAINS
THIS MORNING AND SOME DIURNAL WARMING EXPECTED TO PRODUCE SOME
SCT...MAINLY VFR CUMULUS THIS AFTERNOON INTO EARLY THIS EVENING.
WITH PASSAGE OF THE COLD FRONT...SOUTH-SOUTHWEST WINDS AROUND 15KT
G25KTS WILL GRADUALLY BECOME NORTHWEST THRU THE AFTERNOON...THEN
NORTHWEST TO NORTH AND DECREASE EARLY THIS EVENING AS HIGH PRESSURE
BUILDS EAST ACROSS THE NORTHERN PLAINS. SUBSIDENCE/DRYING CONTINUE
TONIGHT WITH SKC EXPECTED...THEN A FEW DIURNAL 4K-5K FT CUMULUS TUE
MORNING.
&&
.HYDROLOGY...
ISSUED AT 247 PM CDT MON JUN 22 2015
THE STORMS FROM THIS MORNING HIT MUCH OF THE UPPER IOWA RIVER
BASIN AND NORTHERN PORTION OF THE CEDAR RIVER BASIN PRETTY HARD.
COMBINATION OF RADAR AND OBSERVATIONS SHOWED ANYWHERE FROM 3 TO 5
INCHES. THE NORTHERN END OF THE TURKEY AND SOUTHERN END OF THE
KICKAPOO ALSO GOT HIT WITH 1 TO 2 INCHES OF RAIN. AS A
RESULT...THESE RIVERS ARE RISING WITH SOME FLOOD WARNINGS OUT.
SINCE THEY ARE QUICK RESPONDING...MOST SHOULD DROP BELOW FLOOD
STAGE IN THE NEXT 1 TO 2 DAYS...ESPECIALLY GIVEN LITTLE OR NO
ADDITIONAL RAINFALL EXPECTED.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...AJ
LONG TERM...AJ
AVIATION.....RRS
HYDROLOGY...AJ
AREA FORECAST DISCUSSION
NWS CHEYENNE WY
921 PM MDT TUE JUN 23 2015
.UPDATE...
ISSUED AT 857 PM MDT TUE JUN 23 2015
STRONG CAPPING AND A LACK OF ANY SUBSTANTIAL FORCING MECHANISM
PREVENTED CONVECTION ACROSS MUCH OF THE AREA THIS EVE. ALTHOUGH
A FEW STRONG STORMS WERE ABLE TO DEVELOP ACROSS NORTHERN CO...
EVEN LLVL CUMULUS WAS HARD TO COME BAY ACROSS MUCH OF SOUTH
CENTRAL AND SOUTHEAST WY. REMOVED POPS THROUGH THE EARLY TO MID
EVENING AS WE ARE UNLIKELY TO SEE ANY MEASURABLE PCPN THROUGH AT
LEAST 10 PM OR SO. WHILE THE LACK OF CLOUD COVER UPSTREAM OVER
NORTHERN WY IS CONCERNING FOR FUTURE DEVELOPMENT...BELIEVE LARGE
SCALE ASCENT AHEAD OF A MID LEVEL SHORTWAVE MOVING INTO NORTHWEST
WY WILL PROVIDE EXTRA SUPPORT OVERNIGHT ONCE THE NOCTURNAL LLJ
RAMPS UP. GOOD WARM ADVECTION/CONVERGENCE ON THE NOSE OF 30+ KT
WINDS AT H8-H85 FROM EAST CENTRAL WY INTO THE NORTHERN PANHANDLE
SHOULD GIVE WAY TO AT LEAST SCATTERED STORMS. PLENTY OF ELEVATED
INSTABILITY AND STRONG FLOW ALOFT...SO WILL MAINTAIN MENTION OF
SEVERE STORMS ALONG AND NORTH OF A DGW-BFF LINE. BEST CHANCE OF
THIS APPEARS TO BE AFTER MIDNIGHT.
&&
.SHORT TERM...(THIS EVENING THROUGH THURSDAY NIGHT)
ISSUED AT 200 PM MDT TUE JUN 23 2015
VERY CONDITIONAL FORECAST FOR THIS EVENING INTO WEDNESDAY.
FORECAST CHALLENGES DEAL WITH TIMING/LOCATION OF CONVECTION
TONIGHT INTO WEDNESDAY MORNING.
CURRENTLY...VERY HIGH DEW POINTS BEING OBSERVED ACROSS THE
PANHANDLE WESTWARD TO THE LARAMIE RANGE EARLY THIS AFTERNOON. DEW
POINTS RANGE FROM 61 AT SIDNEY...TO 60 AT CHEYENNE TO 55 AT
DOUGLAS AT 1PM. WATER VAPOR IMAGERY SHOWING THE ANTICIPATED UPPER
LEVEL SHORTWAVE CURRENTLY IN SOUTHERN IDAHO THIS AFTERNOON MOVING
AT A FAIRLY GOOD CLIP DUE EAST INTO WEST CENTRAL WYOMING. VISIBLE
SATELLITE IMAGERY STARTING TO SHOW ISOLATED CU DEVELOPMENT OVER
THE NORTHERN PANHANDLE AND POSSIBLY AROUND THE LARAMIE AREA/SOUTH
LARAMIE RANGE.
THE ATMOSPHERE IS STRONGLY CAPPED THIS AFTERNOON EAST OF THE
LARAMIE RANGE. LATEST NAM SOUNDINGS SHOWING RIGHT AROUND 750MB
HERE AT CHEYENNE...730MB AT CHADRON. FORECAST SOUNDINGS KEEP THIS
CAP IN PLACE AT LEAST UNTIL AFTER 00Z WITH CONVECTIVE INHIBITION
ANYWHERE FROM -60 J/KG HERE AT CHEYENNE TO -100 J/KG AT CHADRON
FROM SPC`S PAGE. GOING TO TAKE A WHILE TO BREAK THIS CAP...IF WE
DO IT AT ALL.
DO THINK CURRENT IDEA OF LATE DEVELOPMENT OF THUNDERSTORMS IS
STILL ON TRACK. WITH THE APPROACH OF THE UPPER SHORTWAVE THIS
EVENING...LAPSE RATES SHOULD CONTINUE TO STEEPEN. ALREADY SEEING
THESE STEEP LAPSE RATES IN WESTERN WYOMING AHEAD OF THAT
SHORTWAVE. LATEST HRRR CONVECTIVE SIMULATION SHOWING CONVECTION
BEGINNING TO BREAK OUT AFTER 00Z NEAR LUSK UP INTO NORTHEASTERN
WYOMING. ALSO SHOWING A PRETTY STRONG CELL DEVELOPING FURTHER
SOUTH NEAR CHEYENNE AND MOVING INTO THE SOUTHERN PANHANDLE. SO DO
FEEL THE LATEST SPIC SLIGHT RISK AREA IS STILL IN GOOD SHAPE. WILL
CONTINUE TO ADVERTISE SEVERE THUNDERSTORMS TONIGHT INTO EARLY
WEDNESDAY MORNING.
GFS AND ECMWF QPF OUTPUT HAS CONVECTION PERSISTING INTO 12Z BEFORE
FINALLY ENDING AS THE SHORTWAVE MOVES EAST OF THE FORECAST AREA.
DO HAVE ANOTHER FAIRLY VIGOROUS SHORTWAVE THURSDAY AFTERNOON THAT
COULD KICK OFF SCATTERED SHOWERS. TIMING IS PERFECT FOR AFTERNOON
AND EVENING ISOLATED SEVERE STORMS ONCE AGAIN.
.LONG TERM...(FRIDAY THROUGH TUESDAY)
ISSUED AT 250 PM MDT TUE JUN 23 2015
THE LAST OF A SERIES OF DISTURBANCES WILL EXIT INTO THE EASTERN
GREAT PLAINS FRIDAY WITH ISOLATED AFTERNOON CONVECTION OVER FAR
SOUTHEAST WY AND WESTERN NE. NORTHWEST TO NORTH FLOW IN THE
MID/UPPER LEVELS WILL PREVAIL THIS WEEKEND INTO EARLY NEXT WEEK AS
THE WESTERN CONUS RIDGE BUILDS INTO THE ROCKY MOUNTAINS REGION AND
HIGH PLAINS. THE MODELS...PARTICULARLY THE GFS...CONTINUE TO
DEPICT SOME LIGHT QPF ASSOCIATED WITH DIURNALLY-DRIVEN CONVECTION
OVER THE SOUTHEAST WY MOUNTAINS THIS WEEKEND. COVERAGE WILL BE
ISOLATED. THE PLAINS WILL BE VOID OF CONVECTION AS THE MID LEVELS
WARM. HIGH TEMPERATURES WILL BE WARMING A FEW DEGREES EACH DAY.
CONVECTIVE INHIBITION INCREASES MORESO EARLY WEEK WITH STOUT MID
LEVEL CAP. THE UPSHOT IS A DRY AND WARM FORECAST FOR MONDAY AND
TUESDAY WITH MOSTLY CLEAR SKIES.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z WEDNESDAY EVENING)
ISSUED AT 622 PM MDT TUE JUN 23 2015
MAIN AVIATION CHALLENGE INITIALLY IS TRYING TO PIN DOWN THE
TIMING AND LOCATION OF ISOLD EVENING CONVECTION. THE NEXT UPPER-
LEVEL WEATHER DISTURBANCE IS ON THE DOORSTEP OF AREA TERMINALS
EARLY THIS EVENING...BUT ASIDE FROM A LONE THUNDERSTORM ACROSS
NORTHERN COLORADO...IT HAS DONE LITTLE TO SUGGEST ADDL CONVECTIVE
DEVELOPMENT. THE LATEST FORECAST MODELS CONTINUE TO INDICATE AT
LEAST THE POTENTIAL FOR ISOLATED THUNDERSTORMS THIS EVENING...SO
HAVE LEFT VCTS MENTION IN THIS EVENING AT AIRFIELDS EAST OF THE
MOUNTAINS. REGARDLESS IF THUNDERSTORMS ARE ABLE TO GET GOING THIS
EVENING OR NOT...IT LOOKS LIKE THUNDERSTORM COVERAGE WILL BE
GREATER AFTER 18Z WEDNESDAY. THE OTHER CONCERN OVERNIGHT WILL THE
LIKELY REDEVELOPMENT OF IFR/MVFR CIGS/VSBYS AT ERN PLAINS
TERMINALS 09-15Z TIMEFRAME.
&&
.FIRE WEATHER...
ISSUED AT 200 PM MDT TUE JUN 23 2015
PRETTY DRY CONDITIONS ACROSS CARBON COUNTY AND AREAS WEST OF THE
LARAMIE RANGE. AFTERNOON HUMIDITIES AGAIN EXPECTED TO FALL TO
CRITICAL LEVELS THIS AFTERNOON AND AGAIN WEDNESDAY FOR ZONES
303...304...306 AND POSSIBLY 308. AFTERNOON WIND GUSTS TO 25-30
MPH IN THESE LOCATIONS COULD CREATE ISOLATED AREAS OF CRITICAL
FIRE WEATHER CONDITIONS. BUT SINCE MOST AREAS ARE STILL GREEN ON
FUELS...FIRE WEATHER CONCERNS REMAIN LOW. BETTER CHANCES FOR
WIDESPREAD WETTING RAINS THURSDAY AS AN UPPER LEVEL DISTURBANCE
MOVES INTO THE AREA FROM THE NORTHWEST AND INTERACTS WITH THE
STALLED FRONT ALONG THE LARAMIE RANGE. WETTING RAINS EXPECTED FROM
LARAMIE EAST INTO THE PANHANDLE. MORE DRIER...HIGH BASED
THUNDERSTORMS FOR CARBON COUNTY THURSDAY AFTERNOON/EVENING.
&&
.CYS WATCHES/WARNINGS/ADVISORIES...
WY...NONE.
NE...NONE.
&&
$$
UPDATE...CLH
SHORT TERM...GCC
LONG TERM...MAJ
AVIATION...CAH
FIRE WEATHER...GCC
AREA FORECAST DISCUSSION
NWS CHEYENNE WY
622 PM MDT TUE JUN 23 2015
.SHORT TERM...(THIS EVENING THROUGH THURSDAY NIGHT)
ISSUED AT 200 PM MDT TUE JUN 23 2015
VERY CONDITIONAL FORECAST FOR THIS EVENING INTO WEDNESDAY.
FORECAST CHALLENGES DEAL WITH TIMING/LOCATION OF CONVECTION
TONIGHT INTO WEDNESDAY MORNING.
CURRENTLY...VERY HIGH DEW POINTS BEING OBSERVED ACROSS THE
PANHANDLE WESTWARD TO THE LARAMIE RANGE EARLY THIS AFTERNOON. DEW
POINTS RANGE FROM 61 AT SIDNEY...TO 60 AT CHEYENNE TO 55 AT
DOUGLAS AT 1PM. WATER VAPOR IMAGERY SHOWING THE ANTICIPATED UPPER
LEVEL SHORTWAVE CURRENTLY IN SOUTHERN IDAHO THIS AFTERNOON MOVING
AT A FAIRLY GOOD CLIP DUE EAST INTO WEST CENTRAL WYOMING. VISIBLE
SATELLITE IMAGERY STARTING TO SHOW ISOLATED CU DEVELOPMENT OVER
THE NORTHERN PANHANDLE AND POSSIBLY AROUND THE LARAMIE AREA/SOUTH
LARAMIE RANGE.
THE ATMOSPHERE IS STRONGLY CAPPED THIS AFTERNOON EAST OF THE
LARAMIE RANGE. LATEST NAM SOUNDINGS SHOWING RIGHT AROUND 750MB
HERE AT CHEYENNE...730MB AT CHADRON. FORECAST SOUNDINGS KEEP THIS
CAP IN PLACE AT LEAST UNTIL AFTER 00Z WITH CONVECTIVE INHIBITION
ANYWHERE FROM -60 J/KG HERE AT CHEYENNE TO -100 J/KG AT CHADRON
FROM SPC`S PAGE. GOING TO TAKE A WHILE TO BREAK THIS CAP...IF WE
DO IT AT ALL.
DO THINK CURRENT IDEA OF LATE DEVELOPMENT OF THUNDERSTORMS IS
STILL ON TRACK. WITH THE APPROACH OF THE UPPER SHORTWAVE THIS
EVENING...LAPSE RATES SHOULD CONTINUE TO STEEPEN. ALREADY SEEING
THESE STEEP LAPSE RATES IN WESTERN WYOMING AHEAD OF THAT
SHORTWAVE. LATEST HRRR CONVECTIVE SIMULATION SHOWING CONVECTION
BEGINNING TO BREAK OUT AFTER 00Z NEAR LUSK UP INTO NORTHEASTERN
WYOMING. ALSO SHOWING A PRETTY STRONG CELL DEVELOPING FURTHER
SOUTH NEAR CHEYENNE AND MOVING INTO THE SOUTHERN PANHANDLE. SO DO
FEEL THE LATEST SPIC SLIGHT RISK AREA IS STILL IN GOOD SHAPE. WILL
CONTINUE TO ADVERTISE SEVERE THUNDERSTORMS TONIGHT INTO EARLY
WEDNESDAY MORNING.
GFS AND ECMWF QPF OUTPUT HAS CONVECTION PERSISTING INTO 12Z BEFORE
FINALLY ENDING AS THE SHORTWAVE MOVES EAST OF THE FORECAST AREA.
DO HAVE ANOTHER FAIRLY VIGOROUS SHORTWAVE THURSDAY AFTERNOON THAT
COULD KICK OFF SCATTERED SHOWERS. TIMING IS PERFECT FOR AFTERNOON
AND EVENING ISOLATED SEVERE STORMS ONCE AGAIN.
.LONG TERM...(FRIDAY THROUGH TUESDAY)
ISSUED AT 250 PM MDT TUE JUN 23 2015
THE LAST OF A SERIES OF DISTURBANCES WILL EXIT INTO THE EASTERN
GREAT PLAINS FRIDAY WITH ISOLATED AFTERNOON CONVECTION OVER FAR
SOUTHEAST WY AND WESTERN NE. NORTHWEST TO NORTH FLOW IN THE
MID/UPPER LEVELS WILL PREVAIL THIS WEEKEND INTO EARLY NEXT WEEK AS
THE WESTERN CONUS RIDGE BUILDS INTO THE ROCKY MOUNTAINS REGION AND
HIGH PLAINS. THE MODELS...PARTICULARLY THE GFS...CONTINUE TO
DEPICT SOME LIGHT QPF ASSOCIATED WITH DIURNALLY-DRIVEN CONVECTION
OVER THE SOUTHEAST WY MOUNTAINS THIS WEEKEND. COVERAGE WILL BE
ISOLATED. THE PLAINS WILL BE VOID OF CONVECTION AS THE MID LEVELS
WARM. HIGH TEMPERATURES WILL BE WARMING A FEW DEGREES EACH DAY.
CONVECTIVE INHIBITION INCREASES MORESO EARLY WEEK WITH STOUT MID
LEVEL CAP. THE UPSHOT IS A DRY AND WARM FORECAST FOR MONDAY AND
TUESDAY WITH MOSTLY CLEAR SKIES.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z WEDNESDAY EVENING)
ISSUED AT 622 PM MDT TUE JUN 23 2015
MAIN AVIATION CHALLENGE INITIALLY IS TRYING TO PIN DOWN THE
TIMING AND LOCATION OF ISOLD EVENING CONVECTION. THE NEXT UPPER-
LEVEL WEATHER DISTURBANCE IS ON THE DOORSTEP OF AREA TERMINALS
EARLY THIS EVENING...BUT ASIDE FROM A LONE THUNDERSTORM ACROSS
NORTHERN COLORADO...IT HAS DONE LITTLE TO SUGGEST ADDL CONVECTIVE
DEVELOPMENT. THE LATEST FORECAST MODELS CONTINUE TO INDICATE AT
LEAST THE POTENTIAL FOR ISOLATED THUNDERSTORMS THIS EVENING...SO
HAVE LEFT VCTS MENTION IN THIS EVENING AT AIRFIELDS EAST OF THE
MOUNTAINS. REGARDLESS IF THUNDERSTORMS ARE ABLE TO GET GOING THIS
EVENING OR NOT...IT LOOKS LIKE THUNDERSTORM COVERAGE WILL BE
GREATER AFTER 18Z WEDNESDAY. THE OTHER CONCERN OVERNIGHT WILL THE
LIKELY REDEVELOPMENT OF IFR/MVFR CIGS/VSBYS AT ERN PLAINS
TERMINALS 09-15Z TIMEFRAME.
&&
.FIRE WEATHER...
ISSUED AT 200 PM MDT TUE JUN 23 2015
PRETTY DRY CONDITIONS ACROSS CARBON COUNTY AND AREAS WEST OF THE
LARAMIE RANGE. AFTERNOON HUMIDITIES AGAIN EXPECTED TO FALL TO
CRITICAL LEVELS THIS AFTERNOON AND AGAIN WEDNESDAY FOR ZONES
303...304...306 AND POSSIBLY 308. AFTERNOON WIND GUSTS TO 25-30
MPH IN THESE LOCATIONS COULD CREATE ISOLATED AREAS OF CRITICAL
FIRE WEATHER CONDITIONS. BUT SINCE MOST AREAS ARE STILL GREEN ON
FUELS...FIRE WEATHER CONCERNS REMAIN LOW. BETTER CHANCES FOR
WIDESPREAD WETTING RAINS THURSDAY AS AN UPPER LEVEL DISTURBANCE
MOVES INTO THE AREA FROM THE NORTHWEST AND INTERACTS WITH THE
STALLED FRONT ALONG THE LARAMIE RANGE. WETTING RAINS EXPECTED FROM
LARAMIE EAST INTO THE PANHANDLE. MORE DRIER...HIGH BASED
THUNDERSTORMS FOR CARBON COUNTY THURSDAY AFTERNOON/EVENING.
&&
.CYS WATCHES/WARNINGS/ADVISORIES...
WY...NONE.
NE...NONE.
&&
$$
SHORT TERM...GCC
LONG TERM...MAJ
AVIATION...CAH
FIRE WEATHER...GCC
AREA FORECAST DISCUSSION
NWS DENVER/BOULDER CO
350 AM MDT WED JUN 24 2015
.SHORT TERM...(TODAY THROUGH TONIGHT )
ISSUED AT 350 AM MDT WED JUN 24 2015
THE FLOW ALOFT WILL REMAIN NEARLY ZONAL TODAY THRU TONIGHT WITH SOME
MID LVL MOISTURE MOVING ACROSS THE AREA. EXPECT SCT TSTMS OVER THE
HIGHER TERRAIN THIS AFTN WITH WIDELY SCT ACTIVITY OVER THE VALLEYS.
OVER NERN CO AN OUTFLOW BNDRY FM CONVECTION OVER NWRN NEBRASKA AND
WRN SOUTH DAKOTA WILL EVENTUALLY MOVE INTO NERN CO BY MIDDAY AND
THEN MOVE WESTWARD INTO THE FRONT RANGE BY MID TO LATE AFTN IF HRRR
IS CORRECT. AHEAD OF THIS BNDRY WINDS ARE SUPPOSED TO BECOME MORE
WNW ALONG THE FRONT RANGE AS BEST INSTABILITY STAYS OVER THE FAR
NERN PLAINS FOR MOST OF AFTN. OVERALL NOT SURE HOW THINGS ARE GOING
TO EVOLVE THIS AFTN SO WILL KEEP WDLY SCT TSTMS OVER THE PLAINS.
BEST CHC FOR SVR LOOKS TO BE NE OF A LINE FM GREELEY TO FORT MORGAN
TO LIMON WITH MARGINAL LARGE HAIL AND STG WINDS.
AS FOR HIGHS WILL KEEP READINGS SIMILAR TO YESTERDAY AS 850-700 MB
TEMPS CHANGE LITTLE HOWEVER IF WNW DOWNSLOPE WINDS DO DVLP ALONG THE
FRONT RANGE HIGHS COULD END UP BEING A FEW DEGREES WARMER THAN FCST.
FOR TONIGHT TSTMS SHOULD END OVER THE HIGHER TERRAIN DURING THE
EARLY EVENING HOURS. OVER THE PLAINS MAY SEE SOME ACTIVITY LINGER
INTO THE MID EVENING HOURS WITH AN OUTSIDE CHC OF AN MCS CLIPPING
THE FAR NERN CORNER LATE TONIGHT.
.LONG TERM...(THURSDAY THROUGH TUESDAY)
ISSUED AT 350 AM MDT WED JUN 24 2015
A TYPICAL SUMMER WEATHER PATTERN FOR COLORADO WILL BE IN PLACE
THROUGH THE FORECAST PERIOD...BRINGING TEMPERATURES AROUND
SEASONAL NORMALS AND A CHANCE OR SLIGHT CHANCE OF AFTERNOON
SHOWERS ACROSS THE FORECAST AREA EACH DAY. INITIALLY...MODERATE
WESTERLY FLOW ALOFT WILL BE IN PLACE AS AN UPPER RIDGE CONTINUES
OVER THE SOUTHEASTERN UNITED STATES. AT LOWER AND MID LEVELS...
MOISTURE AND INSTABILITY WILL BE MOVING INTO THE STATE FROM THE
SOUTHERN PLAINS. DAYTIME HEATING WILL DE-STABILIZE THE AIRMASS IN
THE AFTERNOONS...LEADING TO THUNDERSTORM DEVELOPMENT OVER THE
MOUNTAINS AND FOOTHILLS WHICH WILL DRIFT EASTWARD THROUGH THE
EARLY EVENINGS. ON THURSDAY NIGHT A SURFACE COLD FRONT WILL MOVE
INTO NORTHEAST COLORADO...WHICH WILL KEEP TEMPERATURES COOLER ON
FRIDAY. AT THE SAME TIME HIGH PRESSURE ALOFT OVER THE WESTERN U.S.
WILL STRENGTHEN...BRINGING COLORADO UNDER A MORE NORTHWESTERLY
FLOW ALOFT. GULF MOISTURE AT LOW AND MID-LEVELS WILL CONTINUE
MOVING INTO EASTERN COLORADO THROUGH THE WEEKEND AND EACH DAY WILL
BE A BALANCE BETWEEN WEAK SUBSIDENCE DOWNSTREAM FROM THE WESTERN
U.S. UPPER RIDGE AND DAYTIME HEATING OF THE AIRMASS PRODUCING THE
CHANCE OF AFTERNOON SHOWERS EACH DAY. THE NORTHWESTERLY FLOW AT
MID AND UPPER LEVELS COULD ASSIST IN THE DEVELOPMENT OF SHOWER
ACTIVITY DUE TO FAVORABLE VERTICAL WIND SHEAR PROFILES THAT WILL
RESULT. IN THE END...EACH DAY SHOULD SEE PLENTY OF SUNSHINE
THROUGH MORNING AND EARLY AFTERNOONS...AND THEN THE DEVELOPMENT OF
CLOUDS AND SHOWERS THROUGH THE LATE AFTERNOONS. THE EXCEPTION TO
THIS MAY BE FRIDAY MORNING WHEN STRATUS AND LOW CLOUDS WILL BE
POSSIBLE IN THE POST-FRONTAL AIRMASS. THIS WILL BE ADDRESSED IN
LATER FORECASTS.
&&
.AVIATION...(FOR THE TAFS THROUGH 12Z THURSDAY MORNING)
ISSUED AT 350 AM MDT WED JUN 24 2015
THERE IS A WK DENVER CYCLONE NR DIA SO EXPECT LOW CLOUDS AND SOME
FOG TO DVLP BY 11Z TO THE N AND NW OF THE AIRPORT. IF THE WINDS
BECOME LIGHT WNW THEN COULD SEE SOME STRATUS/FOG FOR A FEW HOURS
THRU 14Z AT DIA.
OTHERWISE EXPECT ISOLD TO WDLY SCT HIGHER BASED TSTMS WILL BE
POSSIBLE IN THE 21Z-01Z TIMEFRAME WITH GUSTY OUTFLOW WINDS.
AS FOR WINDS BOTH THE HRRR AND RAP SHOW WINDS BECOMING MORE WNW BY
15Z AND LASTING THRU 18Z. AFTER 18Z THEY DIVERGE AS THE RAP KEEPS
THEM MAINLY WNW THRU THE REST OF THE AFTN WHILE THE HRRR HAS THEM
BECOMING MORE ELY AS A WK BNDRY MOVES IN FM THE NE. FOR NOW WILL
TREND MORE WITH THE HRRR SOLUTION. FOR THIS EVENING WINDS SHOULD
GRADUALLY TREND TOWARDS TO MORE OF A SSW DIRECTION AND REMAIN
DRAINAGE OVERNIGHT.
&&
.HYDROLOGY...
ISSUED AT 350 AM MDT WED JUN 24 2015
STORMS WILL MOVE RATHER QUICKLY THIS AFTN AND EVENING SO RAINFALL
AMOUNTS SHOULD BE MAINLY UNDER A QUARTER INCH.
&&
.BOU WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...RPK
LONG TERM...DANKERS
AVIATION...RPK
HYDROLOGY...RPK
AREA FORECAST DISCUSSION
NWS GOODLAND KS
304 AM MDT WED JUN 24 2015
.SHORT TERM...(THIS AFTERNOON THROUGH WEDNESDAY)
ISSUED AT 154 PM MDT TUE JUN 23 2015
EARLY AFTERNOON WV IMAGERY AND RAP H5 ANALYSIS SHOWS RIDGE STILL IN
PLACE ACROSS SOUTHERN PLAINS WITH WESTERLY ZONAL FLOW ACROSS THE
NORTHERN PLAINS. WEAK SHORTWAVE TROUGHS AND MONSOONAL/PACIFIC FLOW
CONTINUE TO ROTATE ALONG THE WESTERN PERIPHERY OF THE RIDGE AND
INTO THE CENTRAL ROCKIES. AT THE SURFACE STATIONARY FRONT HAS
LIFTED TO NEAR SCOTT CITY JUST SOUTH OF OUR CWA WITH STATIONARY
FRONT ALONG FRONT RANGE.
THIS AFTERNOON-TONIGHT...GUIDANCE CONTINUES TO SHOW WARM FRONT
LIFTING NORTH THROUGH THE AFTERNOON AND EVENING AS LEE TROUGH
DEEPENS. THUNDERSTORMS HAVE ALREADY DEVELOPED ACROSS SOUTH CENTRAL
COLORADO. HIGH RES GUIDANCE CONTINUES TO SHOW CAP WEAKENING
ALONG THE FRONT FROM THE WEST TO THE EAST...AND THUNDERSTORMS
EITHER DEVELOPING OR MOVING INTO THE SW PART OF THE CWA SPREADING
NORTH AND EAST THIS EVENING. WHILE PWATS AND TD VALUES ARE
IMPRESSIVE...DEEP LAYER MIXING RATIOS/MOISTURE PROFILES ARE LESS
THAN FAVORABLE FOR WIDESPREAD COVERAGE LOCALLY WITHOUT
ORGANIZATION INTO MORE OF A CLUSTER FROM THE WEST. SHORTWAVE
TROUGH ADVERTISED TO MOVE ACROSS CWA THIS EVENING COULD HELP WITH
INITIATION...SO DESPITE THE DRY LAYERS ALOFT 20 TO 30 POPS STILL
SEEMS REASONABLE. VEERING SHEER PROFILES IN THE 0-3KM LAYER COULD
HELP SUPERCELL POTENTIAL ASSUMING THUNDERSTORMS DEVELOP THIS
AFTERNOON/EARLY EVENING ALONG WARM FRONT BEFORE LOW LEVELS
STABILIZE. AS EVENING PROGRESSES PROFILES FAVOR MAINLY ELEVATED
THUNDERSTORMS...AND GOOD EFFECTIVE SHEER VALUES SHOULD STILL
SUPPORT LARGE HAIL/DAMAGING WIND THREAT WITH ANY ONGOING ACTIVITY.
WEDNESDAY...WARM FRONT STALLS NEAR THE KS/NE BORDER EARLY WEDNESDAY
MORNING WITH MOISTURE POOLING NORTH OF THIS FRONT EARLY WEDNESDAY
MORNING WHEN FOG/STRATUS COULD DEVELOP. GUIDANCE STILL SHOWING A
POTENTIAL BUT I AM STILL NOT SURE VIS WILL BE LOW ENOUGH TO INCLUDE
MENTION IN FORECAST...SO WILL MONITOR SHORT RANGE
GUIDANCE/TRENDS. FRONT SETS UP ROUGHLY THROUGH THE CENTRAL PART OF
THE CWA AS SURFACE LOW SHIFTS EAST WEDNESDAY AFTERNOON...WITH NEAR
100F TEMPS SOUTH OF THIS FRONT AND IN THE 90S TO THE NW. THIS
FRONT WILL ACT AS A FOCUS FOR POSSIBLY THUNDERSTORM DEVELOPMENT IN
THE AFTERNOON...AGAIN AIDED BY HEIGHT FALLS FROM WEAK SHORTWAVE
ROTATING INTO THE REGION FROM THE WEST. I KEPT 20 POPS CONFINED TO
THE SW IN THE AFTERNOON...THOUGH DEPENDING ON CAP STRENGTH I COULD
SEE A ISOLATED THUNDERSTORM FURTHER EAST. NOT A STRONG SIGNAL IN
THE AFTERNOON FURTHER EAST..SO I FAVOR STICKING WITH A
CONSERVATIVE APPROACH FOR NOW.
.LONG TERM...(SATURDAY THROUGH WEDNESDAY) ISSUED AT 302 AM MDT
WED JUN 24 2015
AT THE BEGINNING OF THE EXTENDED PERIOD MODELS ARE SHOWING THE
LONGWAVE PATTERN AMPLIFYING THROUGH THE END OF THE PERIOD. A
STRONG UPPER RIDGE IS LOCATED TO OUR WEST ALONG THE ROCKIES AND
EXTENDING WELL INTO WESTERN CANADA. AT THE SAME TIME A DEEPENING
TROUGH IS LOCATED OVER THE GREAT LAKES REGION AND EXTENDING IN THE
SOUTHEASTERN U.S. THIS PATTERN SETS UP A PREDOMINANTLY
NORTHWESTERLY UPPER FLOW OVER THE TRI STATE AREA. ON THE SURFACE
THE LOCATED AREA WILL BE UNDER THE INFLUENCE OF A HIGH PRESSURE
CENTER TO THE WEST OF THE CWA.
THERE IS A SLIGHT CHANCES OF PRECIPITATION... MOSTLY IN THE FORM
OF ISOLATED AFTERNOON AND EVENING CONVECTION... ASSOCIATED WITH
THE OCCASIONAL SHORTWAVE TROUGHS THAT WILL MOVE THROUGH THE AREA
FROM THE NORTH. OTHERWISE... EXPECT A MOSTLY DRY PERIOD WITH
TEMPERATURES CLOSER TO NORMAL DUE TO THE NORTHERLY FLOW ALOFT AND
A PERSISTENT EASTERLY SURFACE WINDS.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z WEDNESDAY NIGHT)
ISSUED AT 1027 PM MDT TUE JUN 23 2015
CURRENT RADAR AND STORM TRENDS INDICATE INCREASING CHANCES THAT A
STORM WILL MOVE INTO KMCK NEAR THE BEGINNING OF THIS FORECAST. A
VICINITY THUNDERSTORM CANNOT BE RULED OUT NEAR KGLD AS WELL.
OVERNIGHT STORMS WILL WEAKEN AND DISSIPATE. FORECAST SOUNDINGS
INDICATE STRATUS AT KMCK TOWARD SUNRISE AND THEN BREAKING OUT
AROUND 15Z. CONDITIONS MAY GET CLOSE TO MVFR AT KMCK. DURING THE
DAY WEDNESDAY, EXPECT VFR CONDITIONS AT BOTH SITES WITH A SLIGHT
CHANCE OF THUNDERSTORMS NEAR KGLD DURING THE EVENING.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
SHORT TERM...DR
LONG TERM...BW
AVIATION...FS
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
152 AM CDT WED JUN 24 2015
...UPDATE TO LONG TERM...
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 132 AM CDT WED JUN 24 2015
EARLY MORNING CONVECTION NORTH OF THE I-70 CORRIDOR RELATED WELL
WITH WHERE 850MB WARM AIR CONVECTION, LOCATED NEAR THE NOSE OF A
50KT 850MB JET, WAS OCCURRING JUST NORTH OF THE 700MB 12C TO 14C
BAROCLINIC ZONE. THIS WAS ALSO JUST NORTH OF A SURFACE BOUNDARY
WHICH EXTENDED FROM WEST TO EAST ACROSS NORTH CENTRAL KANSAS. THE
RAP AND NAM WERE BOTH IN GOOD AGREEMENT EARLY THIS MORNING WITH
KEEPING THIS CONVECTION NORTH OF ELLIS AND TREGO COUNTIES AS THESE
THUNDERSTORMS WEAKEN DURING THE EARLY MORNING HOURS. AT THIS TIME
WILL LEAN TOWARDS NOT INSERTING ANY MENTION OF EARLY MORNING
CONVECTION IN THE HAYS OR WAKEENEY AREAS, HOWEVER WILL CONTINUE TO
MONITOR THE ONGOING CONVECTION GIVEN THE DEVELOPING NORTHWEST TO
SOUTHEAST ORIENTATION OF THE 700MB BAROCLINIC ZONE DURING THE
PREDAWN HOURS.
THE WEST TO EAST SURFACE FRONTAL BOUNDARY WILL MOVE NORTH ACROSS
NORTHWEST AND NORTH CENTRAL KANSAS TODAY AS AN UPPER HIGH SHIFTS
SLOWLY NORTH OUT OF NORTHERN OKLAHOMA INTO SOUTHERN KANSAS. THE
WARM 700MB TEMPERATURE THAT WAS LOCATED OVER SOUTHWEST KANSAS AT
00Z WEDNESDAY WILL ALSO LIFT SLOWLY NORTH AND BY 00Z THURSDAY
THESE WARM 700MB TEMPERATURES WILL EXTEND FROM EAST CENTRAL
COLORADO INTO NORTH CENTRAL KANSAS. 850MB NET 24 HOUR TEMPERATURE
TRENDS ACROSS SOUTHWEST KANSAS WILL CHANGE VERY LITTLE BETWEEN 00Z
THURSDAY TO 00Z FRIDAY AS THE 700MB TEMPERATURES COOL BY A COUPLE
OF DEGREES NEAR THE OKLAHOMA BORDER. BASED ON THESE TEMPERATURE
TRENDS AND A MIXING DEPTH OF 800MB WILL STAY CLOSE TO THE PREVIOUS
FORECAST WITH HIGHS RANGING FROM THE MID 90S IN SOUTH CENTRAL
KANSAS TO AROUND 100 DEGREES ACROSS WEST CENTRAL AND NORTH CENTRAL
KANSAS.
CONVECTION LATE THURSDAY SHOULD BE CONFINED NEAR A SURFACE TROUGH
OF LOW PRESSURE THAT WILL BE LOCATED WEST OF THE COLORADO BORDER
AS A WEAK UPPER LEVEL TROUGH EXITS THE ROCKIES AND BEGINS TO CROSS
THE CENTRAL HIGH PLAINS. 21Z THURSDAY AND 00Z FRIDAY CAPE VALUES
FROM THE NAM INDICATED THAT THE INSTABILITY AXIS OF 2000 TO 3000
J/KG WILL STRETCH FROM EASTERN COLORADO INTO NORTHWEST KANSAS LATE
DAY AND EARLY THIS EVENING WITH A 20 KNOT 0-6KM SHEAR. WIDELY
SCATTERED THUNDERSTORMS WILL BE POSSIBLE IN THIS REGION LATE DAY
BUT THESE STORMS ARE EXPECTED WEAKEN/DISSIPATE AS THEY MOVE EAST
INTO A MORE STABLE AIR MASS AFTER SUNSET.
TEMPERATURES TONIGHT WILL BE SIMILAR AS THE LOWS EARLY THIS
MORNING GIVEN A SOUTHERLY WIND AT AROUND 15 MPH, HIGH CLOUDS
SPREADING INCREASING ACROSS WEST CENTRAL/NORTH CENTRAL KANSAS
AFTER MIDNIGHT, AND EARLY MORNING DEWPOINTS IN THE UPPER 50S TO
LOWER 60S.
.LONG TERM...(THURSDAY THROUGH TUESDAY)
ISSUED AT 150 AM CDT WED JUN 24 2015
PRECIP CHANCES PICK UP LATE THIS WEEK AS MEDIUM RANGE MODELS
INDICATE A NORTHWEST FLOW ALOFT DEVELOPING ACROSS THE WESTERN HIGH
PLAINS LATE THURSDAY WHILE AN UPPER LEVEL RIDGE OF HIGH PRESSURE
BUILDS ACROSS THE GREAT BASIN. MEANWHILE, THE GFS AND ECWMF
CONTINUE TO SHOW A SERIES OF H5 VORT MAXIMA COMING OFF THE
AMPLIFYING RIDGE AXIS AND DIGGING SOUTHEAST OUT OF THE NORTHERN
ROCKIES INTO THE PLAINS OF SOUTH DAKOTA AND NEBRASKA. AN ATTENDANT
COLD FRONT IS PROJECTED TO PUSH SOUTHWARD INTO WESTERN KANSAS
SOMETIME THURSDAY NIGHT/EARLY FRIDAY PROVIDING THE FOCUS FOR
POTENTIAL THUNDERSTORMS ACROSS PORTIONS OF CENTRAL AND WESTERN
KANSAS. THE NORTHWEST FLOW ALOFT WILL INCREASE SOME AS AN UPPER
LEVEL JET CRESTING THE RIDGE AXIS OUT WEST, DIGS SOUTHEAST INTO
THE SOUTHERN DAKOTAS AND NEBRASKA. ALONG WITH AMPLE LOW/MID LEVEL
MOISTURE AND INSTABILITY PRESENT, THE POTENTIAL FOR THUNDERSTORMS
WILL INCREASE THURSDAY NIGHT INTO FRIDAY. THUNDERSTORM CHANCES
WILL LESSEN SATURDAY AS THE UPPER LEVEL RIDGE CONTINUES TO AMPLIFY
OUT WEST WHILE THE AFOREMENTIONED COLD FRONT PUSHES FURTHER SOUTH
INTO NORTH TEXAS. THERE IS AN OUTSIDE SHOT AT ISOLATED THUNDERSTORMS
COMING OFF THE ROCKIES WITHIN A SOUTHEASTERLY UPSLOPE FLOW AND
POTENTIALLY DRIFTING INTO EXTREME SOUTHWEST KANSAS SATURDAY
EVENING.
SEASONAL TEMPERATURES WILL CONTINUE THURSDAY EVEN AS A WEAK COLD
FRONT/TROUGH AXIS BEGINS PUSHING INTO NORTHWEST AND NORTH CENTRAL
KANSAS. SO LOOK FOR HIGHS BACK UP INTO THE 90S(F) ACROSS MUCH OF
CENTRAL AND SOUTHWEST KANSAS THURSDAY AFTERNOON. THE COLD FRONT
WILL PUSH FURTHER SOUTH ACROSS SOUTHWEST AND CENTRAL KANSAS INTO
OKLAHOMA LATE THURSDAY NIGHT ALLOWING SLIGHTLY COOLER AIR TO
FILTER SOUTHWARD INTO THE AREA. THIS WILL LOWER HIGHS TO ONLY THE
80S(F) FRIDAY AFTERNOON. HIGHS WILL GRADUALLY REBOUND THROUGHOUT
THE WEEKEND AS A LOW LEVEL SOUTH TO SOUTHEASTERLY FLOW RETURNS TO
WESTERN KANSAS.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z WEDNESDAY NIGHT)
ISSUED AT 1201 AM CDT WED JUN 24 2015
VFR CONDITIONS ARE EXPECTED OVERNIGHT AS ONLY MID AND HIGH LEVEL
MOISTURE PRECEDES AN UPPER LEVEL TROUGH AS IT CROSSES WESTERN
KANSAS. AS THIS UPPER LEVEL DISTURBANCE PASSES SKIES WILL CLEAR
FROM WEST TO EAST EARLY THURSDAY MORNING. SOUTH TO SOUTHWEST WINDS
OVERNIGHT WILL BE AT 10 TO 15 KNOTS. RAP AND NAM WERE SIMILAR WITH
HAVING A 50 KNOT LOW LEVEL JET ACROSS SOUTHWEST KANSAS BETWEEN
06Z AND 12Z. THIS JET AXIS APPEARS TO BE LOCATED NEAR AND WEST OF
GCK AND HYS SO WILL INSERT AS WIND SHEAR GROUP INTO THESE TAFS
THROUGH 12Z THURSDAY. BY LATE MORNING THESE SOUTHERLY WINDS
INCREASE INTO THE 20 TO NEAR 25 KNOTS RANGE AS STRONGER WINDS
LOCATED IN THE 900MB TO 850MB LEVEL BEGIN TO MIX DOWN TO THE
SURFACE. THESE GUSTY WINDS WILL THEN CONTINUE THROUGH THE
REMAINDER OF THE AFTERNOON.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 97 71 96 67 / 0 0 30 30
GCK 98 71 95 65 / 0 10 30 30
EHA 95 69 95 65 / 0 0 30 30
LBL 96 70 97 67 / 0 0 30 30
HYS 100 73 92 65 / 10 10 30 40
P28 98 73 97 70 / 0 0 30 30
&&
.DDC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...BURGERT
LONG TERM...JJOHNSON
AVIATION...BURGERT
AREA FORECAST DISCUSSION...CORRECTED
NWS DODGE CITY KS
136 AM CDT WED JUN 24 2015
...UPDATED SHORT TERM DISCUSSION
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 132 AM CDT WED JUN 24 2015
EARLY MORNING CONVECTION NORTH OF THE I-70 CORRIDOR RELATED WELL
WITH WHERE 850MB WARM AIR CONVECTION, LOCATED NEAR THE NOSE OF A
50KT 850MB JET, WAS OCCURRING JUST NORTH OF THE 700MB 12C TO 14C
BAROCLINIC ZONE. THIS WAS ALSO JUST NORTH OF A SURFACE BOUNDARY
WHICH EXTENDED FROM WEST TO EAST ACROSS NORTH CENTRAL KANSAS. THE
RAP AND NAM WERE BOTH IN GOOD AGREEMENT EARLY THIS MORNING WITH
KEEPING THIS CONVECTION NORTH OF ELLIS AND TREGO COUNTIES AS THESE
THUNDERSTORMS WEAKEN DURING THE EARLY MORNING HOURS. AT THIS TIME
WILL LEAN TOWARDS NOT INSERTING ANY MENTION OF EARLY MORNING
CONVECTION IN THE HAYS OR WAKEENEY AREAS, HOWEVER WILL CONTINUE TO
MONITOR THE ONGOING CONVECTION GIVEN THE DEVELOPING NORTHWEST TO
SOUTHEAST ORIENTATION OF THE 700MB BAROCLINIC ZONE DURING THE
PREDAWN HOURS.
THE WEST TO EAST SURFACE FRONTAL BOUNDARY WILL MOVE NORTH ACROSS
NORTHWEST AND NORTH CENTRAL KANSAS TODAY AS AN UPPER HIGH SHIFTS
SLOWLY NORTH OUT OF NORTHERN OKLAHOMA INTO SOUTHERN KANSAS. THE
WARM 700MB TEMPERATURE THAT WAS LOCATED OVER SOUTHWEST KANSAS AT
00Z WEDNESDAY WILL ALSO LIFT SLOWLY NORTH AND BY 00Z THURSDAY
THESE WARM 700MB TEMPERATURES WILL EXTEND FROM EAST CENTRAL
COLORADO INTO NORTH CENTRAL KANSAS. 850MB NET 24 HOUR TEMPERATURE
CHANGE ACROSS SOUTHWEST KANSAS WILL CHANGE VERY LITTLE BETWEEN
00Z WEDNESDAY TO 00Z THURSDAY AS THE 700MB TEMPERATURES COOL BY A
COUPLE OF DEGREES NEAR THE OKLAHOMA BORDER. BASED ON THESE
TEMPERATURE TRENDS AND A MIXING DEPTH OF 800MB WILL STAY CLOSE TO
THE PREVIOUS FORECAST WITH HIGHS RANGING FROM THE MID 90S IN SOUTH
CENTRAL KANSAS TO AROUND 100 DEGREES ACROSS WEST CENTRAL AND NORTH
CENTRAL KANSAS.
CONVECTION LATE WEDNESDAY SHOULD BE CONFINED NEAR A SURFACE
TROUGH OF LOW PRESSURE THAT WILL BE LOCATED WEST OF THE COLORADO
BORDER AS A WEAK UPPER LEVEL TROUGH EXITS THE ROCKIES AND BEGINS
TO CROSS THE CENTRAL HIGH PLAINS. 21Z WEDNESDAY AND 00Z THURSDAY CAPE
VALUES FROM THE NAM INDICATED THAT THE INSTABILITY AXIS OF 2000 TO
3000 J/KG WILL STRETCH FROM EASTERN COLORADO INTO NORTHWEST KANSAS
LATE DAY AND EARLY THIS EVENING WITH A 20 KNOT 0-6KM SHEAR. WIDELY
SCATTERED THUNDERSTORMS WILL BE POSSIBLE IN THIS REGION LATE DAY
BUT THESE STORMS ARE EXPECTED WEAKEN/DISSIPATE AS THEY MOVE EAST
INTO A MORE STABLE AIR MASS AFTER SUNSET.
TEMPERATURES TONIGHT WILL BE SIMILAR AS THE LOWS EARLY THIS
MORNING GIVEN A SOUTHERLY WIND AT AROUND 15 MPH, HIGH CLOUDS
SPREADING INCREASING ACROSS WEST CENTRAL/NORTH CENTRAL KANSAS
AFTER MIDNIGHT, AND EARLY MORNING DEWPOINTS IN THE UPPER 50S TO
LOWER 60S.
.LONG TERM...(WEDNESDAY NIGHT THROUGH TUESDAY)
ISSUED AT 201 PM CDT TUE JUN 23 2015
ECMWF SHOWS SOME CONVECTION DEVELOPING ACROSS THE EASTERN ZONES
THURSDAY EVENING. THIS MATCHES THE TAIL END OF THE 4 KM NAM.
WILL HAVE CHANCE POPS HERE AND SLIGHT POPS TO THE WEST. WIND AND
HAIL MAY BE POSSIBLE WITH THIS ACTIVITY AS THERE IS LOW END SHEAR
AND MODERATE CAPE. LOWS WILL BE MORE MILD FOR FAR WESTERN KANSAS
FRIDAY MORNING AS COOLER AIR ADVECTS IN. SPEAKING OF, HIGHS FRIDAY
WILL BE COOLER WITH 80S INSTEAD OF 90S POST FRONTAL. LOWS IN THE
60S ARE EXPECTED FOR SATURDAY MORNING. ANOTHER DAY WITH A BREAK IN
THE HEAT IS EXPECTED FOR SATURDAY WITH HIGHS IN THE 80S AGAIN. FOR
NEXT WEEK, THE WARM SECTOR WILL LIFT NORTHWARD WITH 90S RETURNING.
THE REALLY INTENSE HEAT LOOKS TO REMAIN WEST OF HERE AS THE RIDGE
AMPLIFIES OUT WEST AND NORTHERLY FLOW DEVELOPS ACROSS KANSAS.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z WEDNESDAY NIGHT)
ISSUED AT 1201 AM CDT WED JUN 24 2015
VFR CONDITIONS ARE EXPECTED OVERNIGHT AS ONLY MID AND HIGH LEVEL
MOISTURE PRECEDES AN UPPER LEVEL TROUGH AS IT CROSSES WESTERN
KANSAS. AS THIS UPPER LEVEL DISTURBANCE PASSES SKIES WILL CLEAR
FROM WEST TO EAST EARLY THURSDAY MORNING. SOUTH TO SOUTHWEST WINDS
OVERNIGHT WILL BE AT 10 TO 15 KNOTS. RAP AND NAM WERE SIMILAR WITH
HAVING A 50 KNOT LOW LEVEL JET ACROSS SOUTHWEST KANSAS BETWEEN
06Z AND 12Z. THIS JET AXIS APPEARS TO BE LOCATED NEAR AND WEST OF
GCK AND HYS SO WILL INSERT AS WIND SHEAR GROUP INTO THESE TAFS
THROUGH 12Z THURSDAY. BY LATE MORNING THESE SOUTHERLY WINDS
INCREASE INTO THE 20 TO NEAR 25 KNOTS RANGE AS STRONGER WINDS
LOCATED IN THE 900MB TO 850MB LEVEL BEGIN TO MIX DOWN TO THE
SURFACE. THESE GUSTY WINDS WILL THEN CONTINUE THROUGH THE
REMAINDER OF THE AFTERNOON.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 97 71 96 68 / 0 0 20 30
GCK 98 71 95 66 / 0 10 20 20
EHA 98 69 95 66 / 0 0 20 20
LBL 97 70 97 68 / 0 0 20 20
HYS 100 73 92 66 / 10 10 40 40
P28 97 73 97 71 / 0 0 20 40
&&
.DDC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...BURGERT
LONG TERM...99
AVIATION...BURGERT
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
1204 AM CDT WED JUN 24 2015
...UPDATED SYNOPSIS AND AVIATION DISCUSSION...
.SYNOPSIS...
ISSUED AT 1201 AM CDT WED JUN 24 2015
AT 00Z WEDNESDAY A 500MB HIGH EXTENDED FROM NEAR THE FOUR CORNERS
REGION TO EASTERN OKLAHOMA NORTH OF THIS UPPER HIGH A WESTERLY
FLOW EXTENDED FROM THE ROCKIES TO THE MISSISSIPPI VALLEY. WATER
VAPOR LOOP AND 00Z WEDNESDAYS UPPER AIR ANALYSIS INDICATED SEVERAL
WEAK UPPER LEVEL TROUGH EMBEDDED IN THIS WESTERLY FLOW. OVER THE
CENTRAL HIGH PLAINS A SURFACE WARM FRONT EXTENDED FROM AN AREA OF
LOW PRESSURE OVER CENTRAL COLORADO TO EAST CENTRAL KANSAS. 850MB
TEMPERATURES EARLIER THIS EVENING INDICATED A BAROCLINIC ZONE
STRETCHED FROM WESTERN NEBRASKA TO NORTH EASTERN KANSAS AND
TEMPERATURES ACROSS THIS BAROCLNIC ZONE RANGE FROM +26C AT DODGE
CITY TO +14C AT OMAHA. 700MB TEMPERATURES VARIED FROM +12C AT
TOPEKA TO +16C AT DODGE CITY TO +17C AT DENVER.
&&
.SHORT TERM...(THIS EVENING THROUGH WEDNESDAY)
ISSUED AT 324 PM CDT TUE JUN 23 2015
A DRY FORECAST WILL CONTINUE TONIGHT THROUGH WEDNESDAY AS AN
EAST-WEST ORIENTED MID-UPPER TROPOSPHERIC ANTICYCLONE WILL
BASICALLY REMAIN UNCHANGED THROUGH WEDNESDAY. WE WILL CONTINUE TO
SEE STRONG FAIRLY STRONG DIURNAL WINDS ON WEDNESDAY, MUCH LIKE
TODAY. THE MOST INTENSE THERMAL RIDGE WILL BE FROM WEST CENTRAL
INTO NORTHWEST KANSAS ON WEDNESDAY, AND THIS WILL BE WHERE THE
WARMEST TEMPERATURES WILL BE IN THE FORECAST...AROUND 100 FROM
NEAR SYRACUSE NORTHEAST TO WAKEENEY-HAYS. OTHERWISE, MID TO UPPER
90S CAN BE EXPECTED ELSEWHERE. THUNDERSTORMS DEVELOPING ACROSS THE
HIGHER TERRAIN OF COLORADO LATE THIS AFTERNOON/EVENING WILL MOVE
NORTHEAST AND ARE EXPECTED TO REMAIN OUTSIDE OF THE DODGE CITY NWS
AREA OF FORECAST RESPONSIBILITY.
.LONG TERM...(WEDNESDAY NIGHT THROUGH TUESDAY)
ISSUED AT 201 PM CDT TUE JUN 23 2015
ECMWF SHOWS SOME CONVECTION DEVELOPING ACROSS THE EASTERN ZONES
THURSDAY EVENING. THIS MATCHES THE TAIL END OF THE 4 KM NAM.
WILL HAVE CHANCE POPS HERE AND SLIGHT POPS TO THE WEST. WIND AND
HAIL MAY BE POSSIBLE WITH THIS ACTIVITY AS THERE IS LOW END SHEAR
AND MODERATE CAPE. LOWS WILL BE MORE MILD FOR FAR WESTERN KANSAS
FRIDAY MORNING AS COOLER AIR ADVECTS IN. SPEAKING OF, HIGHS FRIDAY
WILL BE COOLER WITH 80S INSTEAD OF 90S POST FRONTAL. LOWS IN THE
60S ARE EXPECTED FOR SATURDAY MORNING. ANOTHER DAY WITH A BREAK IN
THE HEAT IS EXPECTED FOR SATURDAY WITH HIGHS IN THE 80S AGAIN. FOR
NEXT WEEK, THE WARM SECTOR WILL LIFT NORTHWARD WITH 90S RETURNING.
THE REALLY INTENSE HEAT LOOKS TO REMAIN WEST OF HERE AS THE RIDGE
AMPLIFIES OUT WEST AND NORTHERLY FLOW DEVELOPS ACROSS KANSAS.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z WEDNESDAY NIGHT)
ISSUED AT 1201 AM CDT WED JUN 24 2015
VFR CONDITIONS ARE EXPECTED OVERNIGHT AS ONLY MID AND HIGH LEVEL
MOISTURE PRECEDES AN UPPER LEVEL TROUGH AS IT CROSSES WESTERN
KANSAS. AS THIS UPPER LEVEL DISTURBANCE PASSES SKIES WILL CLEAR
FROM WEST TO EAST EARLY THURSDAY MORNING. SOUTH TO SOUTHWEST WINDS
OVERNIGHT WILL BE AT 10 TO 15 KNOTS. RAP AND NAM WERE SIMILAR WITH
HAVING A 50 KNOT LOW LEVEL JET ACROSS SOUTHWEST KANSAS BETWEEN
06Z AND 12Z. THIS JET AXIS APPEARS TO BE LOCATED NEAR AND WEST OF
GCK AND HYS SO WILL INSERT AS WIND SHEAR GROUP INTO THESE TAFS
THROUGH 12Z THURSDAY. BY LATE MORNING THESE SOUTHERLY WINDS
INCREASE INTO THE 20 TO NEAR 25 KNOTS RANGE AS STRONGER WINDS
LOCATED IN THE 900MB TO 850MB LEVEL BEGIN TO MIX DOWN TO THE
SURFACE. THESE GUSTY WINDS WILL THEN CONTINUE THROUGH THE
REMAINDER OF THE AFTERNOON.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 71 96 68 87 / 0 10 10 20
GCK 71 95 66 87 / 10 10 10 20
EHA 69 95 66 88 / 0 10 10 20
LBL 70 97 68 88 / 0 10 10 30
HYS 73 92 66 85 / 10 10 10 20
P28 73 97 71 90 / 0 10 10 30
&&
.DDC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...BURGERT
SHORT TERM...UMSCHEID
LONG TERM...99
AVIATION...BURGERT
AREA FORECAST DISCUSSION
NWS GOODLAND KS
1041 PM MDT TUE JUN 23 2015
.SHORT TERM...(THIS AFTERNOON THROUGH WEDNESDAY)
ISSUED AT 154 PM MDT TUE JUN 23 2015
EARLY AFTERNOON WV IMAGERY AND RAP H5 ANALYSIS SHOWS RIDGE STILL IN
PLACE ACROSS SOUTHERN PLAINS WITH WESTERLY ZONAL FLOW ACROSS THE
NORTHERN PLAINS. WEAK SHORTWAVE TROUGHS AND MONSOONAL/PACIFIC FLOW
CONTINUE TO ROTATE ALONG THE WESTERN PERIPHERY OF THE RIDGE AND
INTO THE CENTRAL ROCKIES. AT THE SURFACE STATIONARY FRONT HAS
LIFTED TO NEAR SCOTT CITY JUST SOUTH OF OUR CWA WITH STATIONARY
FRONT ALONG FRONT RANGE.
THIS AFTERNOON-TONIGHT...GUIDANCE CONTINUES TO SHOW WARM FRONT
LIFTING NORTH THROUGH THE AFTERNOON AND EVENING AS LEE TROUGH
DEEPENS. THUNDERSTORMS HAVE ALREADY DEVELOPED ACROSS SOUTH CENTRAL
COLORADO. HIGH RES GUIDANCE CONTINUES TO SHOW CAP WEAKENING
ALONG THE FRONT FROM THE WEST TO THE EAST...AND THUNDERSTORMS
EITHER DEVELOPING OR MOVING INTO THE SW PART OF THE CWA SPREADING
NORTH AND EAST THIS EVENING. WHILE PWATS AND TD VALUES ARE
IMPRESSIVE...DEEP LAYER MIXING RATIOS/MOISTURE PROFILES ARE LESS
THAN FAVORABLE FOR WIDESPREAD COVERAGE LOCALLY WITHOUT
ORGANIZATION INTO MORE OF A CLUSTER FROM THE WEST. SHORTWAVE
TROUGH ADVERTISED TO MOVE ACROSS CWA THIS EVENING COULD HELP WITH
INITIATION...SO DESPITE THE DRY LAYERS ALOFT 20 TO 30 POPS STILL
SEEMS REASONABLE. VEERING SHEER PROFILES IN THE 0-3KM LAYER COULD
HELP SUPERCELL POTENTIAL ASSUMING THUNDERSTORMS DEVELOP THIS
AFTERNOON/EARLY EVENING ALONG WARM FRONT BEFORE LOW LEVELS
STABILIZE. AS EVENING PROGRESSES PROFILES FAVOR MAINLY ELEVATED
THUNDERSTORMS...AND GOOD EFFECTIVE SHEER VALUES SHOULD STILL
SUPPORT LARGE HAIL/DAMAGING WIND THREAT WITH ANY ONGOING ACTIVITY.
WEDNESDAY...WARM FRONT STALLS NEAR THE KS/NE BORDER EARLY WEDNESDAY
MORNING WITH MOISTURE POOLING NORTH OF THIS FRONT EARLY WEDNESDAY
MORNING WHEN FOG/STRATUS COULD DEVELOP. GUIDANCE STILL SHOWING A
POTENTIAL BUT I AM STILL NOT SURE VIS WILL BE LOW ENOUGH TO INCLUDE
MENTION IN FORECAST...SO WILL MONITOR SHORT RANGE
GUIDANCE/TRENDS. FRONT SETS UP ROUGHLY THROUGH THE CENTRAL PART OF
THE CWA AS SURFACE LOW SHIFTS EAST WEDNESDAY AFTERNOON...WITH NEAR
100F TEMPS SOUTH OF THIS FRONT AND IN THE 90S TO THE NW. THIS
FRONT WILL ACT AS A FOCUS FOR POSSIBLY THUNDERSTORM DEVELOPMENT IN
THE AFTERNOON...AGAIN AIDED BY HEIGHT FALLS FROM WEAK SHORTWAVE
ROTATING INTO THE REGION FROM THE WEST. I KEPT 20 POPS CONFINED TO
THE SW IN THE AFTERNOON...THOUGH DEPENDING ON CAP STRENGTH I COULD
SEE A ISOLATED THUNDERSTORM FURTHER EAST. NOT A STRONG SIGNAL IN
THE AFTERNOON FURTHER EAST..SO I FAVOR STICKING WITH A
CONSERVATIVE APPROACH FOR NOW.
.LONG TERM...(WEDNESDAY NIGHT THROUGH TUESDAY)
ISSUED AT 318 PM MDT TUE JUN 23 2015
FORECAST PROBLEMS WILL BE CHANCES OF THUNDERSTORMS THROUGH FRIDAY.
SATELLITE SHOWING A PROGRESSIVE/NEAR ZONAL FLOW FROM THE PACIFIC
INTO THE WESTERN ATLANTIC. BROAD UPPER RIDGE NOW IN PLACE OVER MOST
OF THE SOUTHERN HALF OF THE COUNTRY.
AT JET LEVEL...MODELS START OUT FINE. AT MID LEVELS...THE CANADIAN
AND GFS WERE DOING A LITTLE BETTER THAN THE NAM AND ECMWF. THE ECMWF
WAS DOING A LITTLE BETTER THAN THE SREF/GFS/NAM ON THE SURFACE WIND
AND PRESSURE FIELD. THE SREF/ECMWF/NAM WERE DOING A LITTLE BETTER
THAN THE REST OF THE OUTPUT ON THE LOW LEVEL THERMAL FIELD.
WEDNESDAY NIGHT...RIGHT REAR QUADRANT OF JET CONTINUES ACROSS THE
NORTHERN HALF OF THE AREA THROUGH THE NIGHT ALTHOUGH IT WEAKENS A
LITTLE LATER IN THE NIGHT. BY LATE IN THE AFTERNOON THE FRONT HAS
SAGGED DOWN THROUGH ABOUT THE WHOLE AREA EXCEPT MAYBE FOR THE
SOUTHERN FRINGE. MID LEVEL SHORTWAVE/LIFT MOVE AFFECT THE
NORTHWEST HALF OF THE AREA THROUGH MIDDLE OF THE NIGHT BEFORE
MOVING OUT OF THE NORTHERN PORTION DURING THE OVERNIGHT HOURS. SO
THE NORTHWEST HALF OF THE AREA WILL HAVE THE HIGHEST POPS
ESPECIALLY THE FAR WEST AND NORTH.
THURSDAY/THURSDAY NIGHT... SHORTWAVE TROUGHS IN NORTHWEST FLOW IS
ALWAYS A TRICKY AND POTENTIALLY ACTIVE SETUP FOR THE AREA. THERE
LOOKS TO BE SOME WEAK LIFT FROM THE RIGHT REAR QUADRANT DURING THE
AFTERNOON. MAIN JET LOOKS TO STAY NORTH OF THE AREA DURING THE
NIGHT. THE FRONT INITIALLY STAYS CLOSE TO THE SOUTHERN PORTION OF
THE AREA BEFORE MOVING EVEN FARTHER SOUTH.
MULTIPLE SHORTWAVE TROUGHS MAKE AFTERNOON AND NIGHTTIME
PRECIPITATION FORECAST MESSY. ONE SHORTWAVE WILL AFFECT THE
SOUTHEAST PORTION OF THE AREA DURING THE AFTERNOON AS ANOTHER WAVE
APPROACHES THE FAR WEST. ALSO POST FRONTAL UPSLOPE OR THE
PROXIMITY OF THE BOUNDARY TO THE WESTERN PORTION OF THE AREA WILL
HELP DEVELOP STORMS. SO AT THIS TIME WILL HAVE SLIGHT CHANCE TO
LOW CHANCE POPS ALONG THE SOUTHEAST AND WESTERN PORTIONS OF THE
AREA.
FOR THE NIGHT...A DECENT BAROCLINIC ZONE LOOKS TO MOVE ACROSS IN
ADVANCE OF A FEW SHORTWAVE TROUGHS. ONE SHORTWAVE TROUGH MOVES
ACROSS THE SOUTHWEST PORTION WITH ANOTHER MOVING ACROSS THE NORTHERN
PORTION. COMBINATION OF THE BAROCLINIC ZONE AND FAVORABLE THETA-E
LAPSE RATES SHOULD ALLOW FOR A GOOD RESPONSE TO THE LIFT. SO CHANCE
POPS WILL TRANSITION FROM NORTHWEST TO SOUTHEAST DURING THIS TIME.
SEE THE POTENTIAL FOR THE POPS TO BE RAISED FROM THIS.
AS STATED ABOVE MOST IF NOT ALL OF THE AREA WILL BE IN POST FRONTAL
UPSLOPE FLOW AND LINGERING CLOUD COVER. AS A RESULT THE HIGH
TEMPERATURES WILL BE COOLER. DEPENDING ON HOW LONG LOW LEVEL CLOUD
COVER LASTS...TEMPERATURES MAY NEED TO BE MADE EVEN COOLER THAN WHAT
IS IN THERE NOW.
FRIDAY...MAIN JET REMAINS NORTH OF THE AREA. DECENT BAROCLINIC ZONE
AND COLD AIR ADVECTION WILL CONTINUE TO MOVE ACROSS DURING THE DAY.
SHORTWAVES WILL ROTATE THROUGH THE NORTHERLY FLOW ALOFT WITH A
MODERATELY STRONG SHORTWAVE MOVING THROUGH FROM LATE IN THE
MORNING THROUGH MID AFTERNOON. SO HAVE SLIGHT TO CHANCE POPS FOR
NOW.
COLD AIR ALOFT...POST FRONTAL SURFACE WINDS...CLOUD COVER AND
PRECIPITATION WILL HELP KEEP TEMPERATURES FROM RISING TOO MUCH.
TEMPERATURES LOOK TO BE COOLER THAN THE PREVIOUS DAY BUT ONCE AGAIN
THE POTENTIAL IS THERE AGAIN TO HAVE TO MAKE THESE TEMPERATURES
COOLER.
FRIDAY NIGHT THROUGH TUESDAY...PATTERN WILL AMPLIFY THROUGH THE
PERIOD WITH A RATHER STRONG/SHARP UPPER RIDGE TO OUR WEST. MODELS
ARE IN GOOD AGREEMENT WITH THIS. PERIODIC SHORTWAVE TROUGHS ALONG
WITH THE ASSOCIATED SURFACE FEATURES WILL MOVE THROUGH IN THE
NORTHWEST TO EVENTUALLY NORTH FLOW ALOFT.
HARD TO RULE OUT PRECIPITATION IN THIS PERIOD. AT THIS TIME...IT
LOOKS LIKE ISOLATED AFTERNOON AND EVENING CONVECTION...MAINLY IN MY
WESTERN/NORTHERN PORTIONS THROUGH THE PERIOD. THE CRH_INIT DEPICTED
THIS SCENARIO NICELY AND DID NOT CHANGE THE POPS THAT I WAS GIVEN.
THE ONLY TRULY DRY PERIOD LOOKS TO BE MONDAY AND MONDAY NIGHT.
TEMPERATURES SHOULD NOT GET TOO HOT OR WAY ABOVE NORMAL DUE TO THE
NORTHERLY FLOW ALOFT AND PERSISTENT EASTERLY SURFACE WINDS OF SOME
SORT. THIS IS ALSO DEPICTED NICELY BY THE INIT AND DID NOT CHANGE.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z WEDNESDAY NIGHT)
ISSUED AT 1027 PM MDT TUE JUN 23 2015
CURRENT RADAR AND STORM TRENDS INDICATE INCREASING CHANCES THAT A
STORM WILL MOVE INTO KMCK NEAR THE BEGINNING OF THIS FORECAST. A
VICINITY THUNDERSTORM CANNOT BE RULED OUT NEAR KGLD AS WELL.
OVERNIGHT STORMS WILL WEAKEN AND DISSIPATE. FORECAST SOUNDINGS
INDICATE STRATUS AT KMCK TOWARD SUNRISE AND THEN BREAKING OUT
AROUND 15Z. CONDITIONS MAY GET CLOSE TO MVFR AT KMCK. DURING THE
DAY WEDNESDAY, EXPECT VFR CONDITIONS AT BOTH SITES WITH A SLIGHT
CHANCE OF THUNDERSTORMS NEAR KGLD DURING THE EVENING.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
SHORT TERM...DR
LONG TERM...BULLER
AVIATION...FS
AREA FORECAST DISCUSSION
NWS NEW ORLEANS LA
333 AM CDT WED JUN 24 2015
.SHORT TERM...
CURRENTLY MONITORING TRENDS AND EVOLUTION OF CONVECTION OVER
ALABAMA AND NORTHERN MISSISSIPPI THIS MORNING AS A RESULT OF A
LARGE OUTFLOW BOUNDARY THAT IS MOWING SOUTHWEST THROUGH AN
UNSTABLE AIR MASS. THE SOUTHERN ALABAMA ACTIVITY HAS CONGEALED
INTO A RATHER LARGE AND EXPANDING MCS WITH PLENTY OF IN-CLOUD
LIGHTNING AND ONLY ABOUT 10 PERCENT CLOUD-TO-GROUND PRODUCTION.
THE LARGER SCALE MODELS ARE NOT HANDLING THIS DEVELOPMENT
PARTICULARLY WELLL BUT THE HIGHER RESOLUTION SHORT-RANGE
CONVECTIVE BASED MODELS LIKE THE HRRR AND WRF ARE LATCHED IN ON
CURRENT TRENDS. AS A RESULT...HAVE OPTED TO INCREASE RAIN CHANCES
TO 50 PERCENT WITH EARLY ONSET ON THE MISSISIPPI COAST...AND
EARLIER THAN TYPICAL IN LOUISIANA BY MID-MORNING. HIGH CAPE AND
LOW SHEAR ENVIRONMENT WOULD SUGGEST MAIN THREAT TO BE WET
MICROBURSTS OVER LAND AREAS AFTER SUNRISE AND TYPE II WATERSPOUT
PRODUCTION IN THE COASTAL WATERS AND POSSIBLY OVER AREA BAYS AND
INLAND WATERWAYS. RAINFALL CAN ALSO BE EFFICIENT WITH SOME
LOCALIZED PONDING POSSIBLE...THOUGH MUCH OF THE RAINFALL WILL BE
ANVIL DECAY TYPE AWAY FROM THE PRIMARY CORES. MOVEMENT AND
PROPAGATION DUE TO OUTFLOW SHOULD BE ABLE TO KEEP STORM TOTAL
RAINFALL AT MANAGEABLE LEVELS TODAY. CONVECTION WILL ALSO LIKELY
DISRUPT THE SEA BREEZE CYCLE TODAY...OR AT LEAST GREATLY DELAY THE
ONSET UNTIL MUCH LATER IN THE AFTERNOON AS THE AIR MASS WILL NEED
TIME TO RECOVER AFTER MORNING CONVECTION AND INDUCTION OF DEEPER
NORTHERLY FLOW ALOFT. OTHERWISE...TEMPERATURES OF MODEL CONSENSUS
WILL BE PROVIDED BUT MAY BE IN LINE FOR SOME BUSTS OR AT LEAST
ATYPICAL DIURNAL TREND BEHAVIORS DUE TO CLOUD COVER EARLY ON.
FRIDAY COULD BE A REPEAT AS A COLD POOL REMAINS IN PLACE ALOFT AND
NOCTURNAL CONVECTION MAY ONCE AGAIN ERUPT DUE TO OUTFLOW FEATURES
GENERATED FROM CONVECTION ALONG THE FRINGES OF UPPER RIDGE FARTHER
NORTH.
.LONG TERM...
MODELS ARE STILL IN VERY GOOD AGREEMENT WITH LARGE SCALE TROUGHING
TO TAKE PLACE OVER THE WEEKEND. THIS SHOULD ALLOW A SURFACE
FRONTAL FEATURE TO SETTLE INTO THE AREA...POSSIBLY DROPPING INTO
THE NORTH GULF LATE SUNDAY...AND PROVIDING A GENERALLY COOLING TO
AT LEAST NEAR NORMAL TEMPERATURES FOR NEXT WEEK. THE PATTERN WOULD
ALSO FAVOR INCREASED CHANCES AT RAINFALL EACH DAY POSSIBLY IN MCS
FASHION IN BASE OF TROUGH BY MID-WEEK. CONSENSUS MODEL GUIDANCE ON
TEMPERATURES AND POPS DURING THE EXTENDED PORTION. 24/RR
&&
.AVIATION...
EXPECT VFR CONDITIONS TO PREVAIL THROUGH THE TAF PERIOD WITH
GENERALLY LIGHT AND VARIABLE WINDS. HOWEVER OVERNIGHT CONVECTION
FROM SOUTH CENTRAL ALABAMA CONTINUES TO DRIFT TOWARDS THE FORECAST
AREA THIS MORNING AND WILL PROBABLY HAVE TO AMEND TAFS BEFORE THE
12Z ISSUANCE TO ADD THUNDERSTORMS INTO THE KGPT TAF AND TO START
CONVECTION EARLIER AT KMCB AND KASD. WILL HAVE TO CONTINUE TO WATCH.
GUSTY WINDS AND FREQUENT LIGHTNING WILL BE THE MAIN THREATS. VSBY
WITHIN THUNDERSTORMS COULD DROP TO IFR CONDITIONS BUT OUTSIDE
OF CONVECTION EXPECT MOSTLY VFR CONDITIONS. 13/MH
&&
.MARINE...
A WEAK SURFACE RIDGE REMAINS ACROSS THE REGION WITH NO
MAJOR CHANGES TO THE FORECAST AS WINDS WILL BE GENERALLY 10 KNOTS OR
LESS. ISOLATED TO SCATTERED CONVECTION IS POSSIBLE EACH AFTERNOON.
THE PATTERN SHOULD BE BROKEN BY AN APPROACHING COLD FRONT ON
SATURDAY AS WIND SPEEDS AND SEAS WILL BEGIN TO PICK UP. 13/MH
&&
.DECISION SUPPORT...
DSS CODE...BLUE.
DEPLOYED...NONE.
ACTIVATION...NONE.
ACTIVITIES...RIVER FLOOD WARNINGS ON MISSISSIPPI RIVER.
DECISION SUPPORT SERVICES (DSS) CODE LEGEND
GREEN = NO WEATHER IMPACTS THAT REQUIRE ACTION
BLUE = LONG FUSED WATCH/WARNING/ADVISORY IN EFFECT OR HIGH
VISIBILITY EVENT
YELLOW = HEIGHTENED IMPACTS WITH SHORT FUSED WATCH/WARNING/ADVISORY
ISSUANCES; RADAR SUPPORT
ORANGE = HIGH IMPACTS - SLIGHT TO MODERATE RISK SEVERE; NEARBY
TROPICAL EVENTS; HAZMAT OR OTHER LARGE EPISODES
RED = FULL ENGAGEMENT FOR MODERATE RISK SVR AND/OR DIRECT
TROPICAL THREATS; EVENTS OF NATIONAL SIGNIFICANCE
&&
.PRELIMINARY POINT TEMPS/POPS...
MCB 94 74 91 74 / 50 30 40 20
BTR 95 76 92 75 / 50 30 40 10
ASD 94 77 91 77 / 50 20 40 20
MSY 94 78 91 77 / 50 20 40 20
GPT 93 79 91 78 / 50 30 40 20
PQL 93 77 91 78 / 50 30 30 20
&&
.LIX WATCHES/WARNINGS/ADVISORIES...
LA...NONE.
GM...NONE.
MS...NONE.
GM...NONE.
&&
$$
24/RR
13/MH
AREA FORECAST DISCUSSION...UPDATED
NWS JACKSON MS
1104 PM CDT TUE JUN 23 2015
.UPDATE...CLUSTER OF STORMS OVER TN WILL MAKE A MORE SOUTHWARD
PUSH AND LIKELY ENTER THE N-CENTRAL AND NE PORTIONS OF THE CWA AS IT
BEGINS TO WEAKEN. THE LATEST ANALYSIS ALONG WITH HRRR GUID SUPPORTS
THE STORM CLUSTER TO MAKE A MUCH FURTHER SOUTHWARD PROGRESS THAN
EXPECTED. LOW LEVEL TRAJECTORIES SUPPORT STORM PROPAGATION INTO THE
NE CWA WITH TIMING OF THE CLUSTER BETWEEN 1-2 AM. VERY ANOMALOUS
HEAT/HUMIDITY EXIST FOR THIS TIME OF EVENING AND SBCAPE IS HOLDING
AT ROUGHLY 4000 J/KG ALONG WITH SFC THETA E >360 K AND 850MB THETA E
AROUND 350 K. THESE INGREDIENTS SHOULD BE PLENTY TO SUPPORT THESE
STORMS AS THEY ENTER N/NE MS BUT EXPECTATIONS ARE FOR THINGS TO
BECOME LESS FAVORABLE AS THEY NEAR THE CWA BOARDER AND THE HWY 82
CORRIDOR. AT THIS POINT...JUST STRONG GUSTS ARE EXPECTED BUT SOME
SEVERE THREAT CANNOT BE TOTALLY RULED OUT. HOWEVER...WILL SIDE WITH
THE HRRR AND FORECAST WEAKENING AS IT NEARS THE CWA. THE FORECAST
HAS BEEN ADJUSTED TO INCREASE POPS. /CME/
&&
.AVIATION...VFR CONDITIONS WILL PREVAIL MORE HAZY HOT CONDITIONS.
LIKE THE PREV DAYS...THE HAZE LOOKS TO NOT IMPACT CONDITIONS WITH
VIS REMAINING AT 6SM OR GREATER. MORE OF AN OPPORTUNITY FOR
CONVECTION LOOKS TO EXIST AFTER 21Z WED AND VCTS WAS INCLUDED FOR
THAT PERIOD AT A FEW LOCATIONS. /CME/
&&
.PRELIMINARY POINT TEMPS/POPS...
JACKSON 77 96 76 93 / 9 33 27 40
MERIDIAN 76 96 74 94 / 13 38 27 45
VICKSBURG 76 96 75 93 / 6 29 25 33
HATTIESBURG 76 97 75 93 / 5 48 37 50
NATCHEZ 75 94 75 91 / 5 37 32 35
GREENVILLE 76 98 77 95 / 12 18 14 31
GREENWOOD 76 95 76 94 / 25 21 16 34
&&
.JAN WATCHES/WARNINGS/ADVISORIES...
MS...HEAT ADVISORY FROM 11 AM TO 7 PM CDT WEDNESDAY FOR MSZ026>033-
036>039-042>046-048>052.
HEAT ADVISORY UNTIL 7 PM CDT WEDNESDAY FOR MSZ018-019-025-034-
035-040-041-047-053.
LA...HEAT ADVISORY UNTIL 7 PM CDT WEDNESDAY FOR LAZ007>009-015-016-
023-025.
AR...HEAT ADVISORY UNTIL 7 PM CDT WEDNESDAY FOR ARZ074-075.
&&
$$
CME
AREA FORECAST DISCUSSION
NWS SPRINGFIELD MO
1202 AM CDT Wed Jun 24 2015
.SHORT TERM...(This Evening through Thursday)
Issued at 200 PM CDT TUE JUN 23 2015
A front has stalled out across the area. This frontal boundary
shows up very nicely on the visible satellite imagery and surface
obs this afternoon. The front was currently located from near
Nevada to near Eminence. This front will start to slowly back up
northward later this evening and tonight. There is a complex of
storms northwest of the Kansas City area which are moving east-
southeastward.
The latest Hi-Res models suggest this complex if it holds together
may clip our central Missouri counties late this afternoon and
early evening. The HRRR and the ARW continues to suggest a few
isolated showers and storms developing near the stalled out
frontal boundary across central Missouri into the eastern Missouri
Ozarks. There will be a limited risk for a strong storm or two
with small hail and gusty winds as the main threat. Any convection
should either dissipate or move off to the east of the area after sunset.
Wednesday and Thursday will be hot and humid with the upper level
ridge nosing in a bit over the area. High temperatures may be a
couple degrees warmer than today with most areas in the lower to
middle 90s. Heat index will be around 100. Southwest winds will be
gusty up to 30 mph for areas west of Highway 65.
.LONG TERM...(Thursday Night through Tuesday)
Issued at 200 PM CDT TUE JUN 23 2015
A stronger shortwave will move through the Midwest and Ohio River
Valley region on Friday. This feature will begin to carve out a
trough across the eastern U.S. while an upper level ridge builds
across the western U.S. A cold front will move down into the
region starting Thursday night. Showers and thunderstorms will
begin to impact portions of central Missouri late Thursday night
and area wide by Friday. Will not rule out a few strong storms
possible Friday with gusty winds and small hail the main threats.
The front will clear through the area by Friday night with rain
ending from north to south.
The weekend is shaping up to be extremely nice. Drier air will
move into the area with dewpoints in the 50s. The latest model
guidance came in a degree or two cooler with lows Saturday night
and Sunday night in the upper 50s to lower 60s. Highs will be in
the upper 70s to lower 80s and Mostly sunny skies. Looks like the
below average temperatures will continue into early next week.
Another weak front may try to move into the area by Monday night
with a few showers and storms possible.
&&
.AVIATION...(For the 06Z TAFS through 06Z Wednesday Night)
Issued at 1159 PM CDT TUE JUN 23 2015
Mostly clear skies and VFR conditions will continue through
Wednesday evening. Winds will increase out of the southwest on
Wednesday and will become somewhat gusty around Joplin.
&&
.SGF WATCHES/WARNINGS/ADVISORIES...
MO...NONE.
KS...NONE.
&&
$$
SHORT TERM...Griffin
LONG TERM...Griffin
AVIATION...Schaumann
AREA FORECAST DISCUSSION
NWS BISMARCK ND
1220 AM CDT WED JUN 24 2015
.UPDATE...
ISSUED AT 1216 AM CDT WED JUN 24 2015
NO MAJOR CHANGES WITH THIS UPDATE. THUNDERSTORMS CONTINUE TO
DIMINISH EARLY THIS MORNING. ANOTHER ROUND OF THUNDERSTORMS IS
EXPECTED LATER THIS MORNING ACROSS EASTERN MONTANA AND WESTERN
NORTH DAKOTA.
UPDATE ISSUED AT 937 PM CDT TUE JUN 23 2015
THE CHALLENGE FOR THE REMAINDER OF THE NIGHT IS THE COVERAGE AND
INTENSITY OF CONVECTION LATE TONIGHT ACROSS WESTERN AND CENTRAL
NORTH DAKOTA FROM THUNDERSTORM ACTIVITY THAT WILL PROPAGATE EAST
FROM CENTRAL AND EASTERN MONTANA. THE 01 UTC RAP DEPICTS MULTIPLE
IMPULSES EVIDENCED BY ONGOING CONVECTION ACROSS MONTANA
PROPAGATING INTO NORTH DAKOTA TONIGHT. 850 MB CAPE VALUES ARE IN
THE 500-800 J/KG RANGE WITH STRONG DEEP LAYER SHEAR WITH THE FAST
WESTERLIES ALOFT. THUS...SMALL HAIL APPEARS TO BE THE LIKELY
THREAT WITH SCATTERED CONVECTION SUSTAINED BY A STRENGTHENING LOW
LEVEL JET AND WARM AIR ADVECTION INTO NORTH DAKOTA.
UPDATE ISSUED AT 543 PM CDT TUE JUN 23 2015
THE 19-21 UTC HRRR ITERATIONS HAVE A GOOD HANDLE ON THE ONGOING
CONVECTION ACROSS WESTERN NORTH DAKOTA...AND WILL USE A BLEND OF
THEIR SOLUTIONS FOR SKY COVER AND POPS THROUGH THE EVENING AND
OVERNIGHT.
A MARGINAL THREAT FOR LARGE HAIL AND DAMAGING WINDS WILL CONTINUE
ACROSS SOUTHWEST AND POSSIBLY INTO SOUTH CENTRAL NORTH DAKOTA
THROUGH SUNSET. THE 22 UTC RAP ANALYSIS DEPICTS STRONG DEEP LAYER
SHEAR OF 40 KTS...WITH ML CAPE VALUES AROUND 1000-1500 J/KG...400
J/KG OF HAIL CAPE AND DOWNDRAFT CAPE AROUND 1000 J/KG.
OVERALL...DEEPER MOISTURE APPEARS TO BE A MITIGATING FACTOR FOR
GREATER STORM INTENSITY. MULTIPLE FUNNEL CLOUD REPORTS HAVE ALSO
BEEN RECEIVED ACROSS THE SOUTHWEST GIVEN THE AT TIMES SUPERCELLUR
NATURE OF THE STORMS. HOWEVER...LOW LEVEL KINEMATIC FIELDS ARE NOT
OVERLY SUPPORTIVE OF TORNADOES.
&&
.SHORT TERM...(THIS AFTERNOON THROUGH WEDNESDAY)
ISSUED AT 129 PM CDT TUE JUN 23 2015
FORECAST HIGHLIGHTS IN THE SHORT TERM PERIOD WILL BE CHANCES FOR
THUNDERSTORMS THROUGH THE PERIOD...SOME MARGINALLY SEVERE SOUTHWEST
THIS AFTERNOON/EVENING...AND ACROSS WESTERN AND CENTRAL NORTH DAKOTA
WEDNESDAY.
CURRENTLY...ACTIVE WEST-NORTHWEST FLOW ALOFT WITH A SFC TROUGH
STATIONARY ACROSS THE NORTHERN HIGH PLAINS OF MT/WY. UPPER LEVEL
DIVERGENCE IN THE EXIT REGION OF AN UPPER LEVEL JET COUPLED WITH
DIURNAL INSTABILITY WILL SEE THE CHANCE FOR SHOWERS AND
THUNDERSTORMS THIS AFTERNOON WEST AND NORTH...THEN SPREADING SLOWLY
SOUTHEAST TONIGHT. BEST CHANCE FOR STRONGER STORMS REMAINS ACROSS
THE WESTERN THIRD OF THE STATE...MORE SO THE SOUTHWEST WHERE MODELS
PORTRAY 800-1200 J/KG OF MUCAPE ALONG WITH 50KTS OF 0-6KM SHEAR.
LATEST HRRR ALONG WITH THE 00Z 4KM NSSL WRF INDICATE CONVECTIVE
DEVELOPMENT EARLY TO MID AFTERNOON FROM EASTERN MONTANA INTO
SOUTHWEST AND WEST CENTRAL NORTH DAKOTA. WILL MAINTAIN HIGH CHANCE
SCATTERED POPS FOR THIS AREA.
FOR WEDNESDAY...FLOW ALOFT AND UPPER DIVERGENCE REMAINS UNCHANGED
OVER THE NORTHERN PLAINS. SFC TROUGH ADVANCES EAST WED MORNING AND
AFTERNOON INTO THE CENTRAL DAKOTAS. DAYTIME INSTABILITY AND BULK
SHEAR INDICATE CHANCE FOR THUNDERSTORMS AREA WIDE...MARGINALLY
SEVERE OVER THE ENTIRE COUNTY WARNING AREA (ALL OF WEST AND CENTRAL
ND). WILL MAINTAIN POSSIBLE SEVERE WORDING IN THE HWO. DUE TO THE
UNCERTAINTY...OPTED TO NOT INCLUDE IN THE GRIDS AT THIS TIME.
.LONG TERM...(WEDNESDAY NIGHT THROUGH TUESDAY)
ISSUED AT 129 PM CDT TUE JUN 23 2015
CHANCES FOR SHOWERS AND THUNDERSTORMS ARE EXPECTED TO PERSIST INTO
WEDNESDAY NIGHT...AS AN UPPER LEVEL SHORTWAVE TROUGH CONTINUES ON AN
EASTWARD TRACK OUT OF THE STATE.
A TRANSITION FROM QUASI ZONAL FLOW ALOFT INTO NORTHWEST FLOW IS
EXPECTED THROUGH THURSDAY. THE CURRENT MODEL PACKAGE PROVIDES GOOD
AGREEMENT ON NORTH/NORTHWEST FLOW ALOFT REMAINING IN PLACE THROUGH
THE REST OF THE EXTENDED. SEVERAL EMBEDDED MID-LEVEL SHORTWAVES ARE
PROJECTED ACROSS THE AREA...RESULTING IN FREQUENT CHANCES FOR
ISOLATED/SCATTERED THUNDERSTORMS THOUGH PREDICTABILITY IS LOW.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z WEDNESDAY NIGHT)
ISSUED AT 1216 AM CDT WED JUN 24 2015
VFR CONDITIONS EXPECTED AT ALL TAF SITES THROUGH THE PERIOD.
THUNDERSTORMS ARE ONCE AGAIN POSSIBLE BEGINNING LATE THIS MORNING
AND EARLY THIS AFTERNOON ACROSS WESTERN NORTH DAKOTA AND
SPREADING EAST THROUGH THE EVENING.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...AJ
SHORT TERM...NH
LONG TERM...AC
AVIATION...AJ
AREA FORECAST DISCUSSION
NWS GREENVILLE-SPARTANBURG SC
452 AM EDT WED JUN 24 2015
.SYNOPSIS...
STRONG MID LEVEL HIGH PRESSURE WILL PERSIST ACROSS THE REGION
THROUGH THE REMAINDER OF THE WORK WEEK...MAINTAINING WELL ABOVE
NORMAL TEMPERATURES. A BROAD UPPER LEVEL TROF WILL MOVE OVER THE
REGION OVER THE WEEKEND RETURNING TEMPERATURES TO SEASONAL LEVELS BY
SUNDAY AND INCREASING CHANCES FOR WIDESPREAD SHOWERS AND
THUNDERSTORMS. A COOLER AND DRIER PATTERN WILL TAKE SHAPE AFTER A
FRONT PASSES EARLY IN THE WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 445 AM EDT...THE LATEST HRRR RUNS ALLOW ANY LINGERING ERN TN
CONVECTION TO DIMINISH OVER THE WESTERN MOUNTAINS THROUGH DAYBREAK.
OTHERWISE...THE WEAK SURFACE FRONTAL BOUNDARY WILL STALL IN THE
FORECAST AREA TODAY AND THEN LIKELY LIFT NORTHWARD AS A WARM FRONT
TONIGHT. THE HRRR HAS ALSO TRENDED TOWARD BETTER TSTM COVERAGE IN
SRN SECTIONS THIS AFTN...SOUTH OF THE BOUNDARY. MODEL PROFILES
REMAIN FAIRLY WARM ALOFT...HOWEVER...SEVERE WEATHER WILL BE A THREAT
WITH ANY TSTMS THAT FORM AS MODERATE OR BETTER CAPE LOOKS LIKELY
ALONG WITH MID LEVEL DRY AIR AND ASSOCIATED THETA E LAPSES YIELDING
SOME MEASURE OF MICROBURST POTENTIAL. THE SRN HALF WILL BE MOST AT
RISK GIVEN THE BOUNDARY LOCATION AND LIKELY SBCAPE VALUES OF 3000 TO
3500 J/KG THERE DURING PEAK HEATING.
TEMPERATURES AND ASSOCIATED HEAT INDEX VALUES WILL BE THE OTHER
ISSUE FOR THE FORECAST TODAY. BL AND 850 TEMPS LOOK COMPARABLE TO
YESTERDAY...BUT SO DOES THE POTENTIAL FOR SOME DEWPOINT MIXING IN
THE WARMEST PIEDMONT SECTIONS. PLUS...THERE COULD BE DEBRIS CLOUDS
AROUND AT TIMES TODAY. WILL KEEP HEAT INDEX VALUES IN THE SRN
PIEDMONT AT 100 TO 104 THIS AFTN. ANTICIPATE ANOTHER VERY MILD NIGHT
WITH PRECIPITATION CHANCES STEADILY WANING WITH THE LOSS OF HEATING.
&&
.SHORT TERM /THURSDAY THROUGH FRIDAY/...
AS OF 245 AM WEDNESDAY...ON THURSDAY...THE H5 AND H7 RIDGE WILL
REMAIN CENTERED OVER THE DEEP SOUTH. HOWEVER...HEIGHTS SHOULD RISE
FROM THE SOUTH AS THE RIDGE CENTER DRIFTS EAST DURING THE DAY. USING
A BLEND OF PREFERRED GUIDANCE...I WILL FORECAST HIGHS AROUND 90
WITHIN THE MTN VALLEYS TO MID TO HIGH 90S ACROSS THE FOOTHILLS AND
PIEDMONT. A WEST TO EAST FRONT WILL REMAIN ACROSS THE OHIO RIVER
VALLEYS AS A SFC TROF COVERS THE FOOTHILLS AND PIEDMONT. GIVEN THE
SFC PATTERN...LLVL WINDS ARE FORECAST TO REMAIN LIGHT FROM THE WSW.
FORECAST SOUNDINGS REVEAL THAT A SIGNIFICANT LAYER OF CIN WILL
REMAIN AROUND H75...VALUES RANGING FROM 40-60 J/KG. THE LACK OF
FORCING AND LINGERING CAPPING SHOULD FAVOR LITTLE TO NO COVERAGE OF
DEEP CONVECTION ON THURSDAY. I WILL FORECAST DRY CONDITIONS EAST OF
THE MTNS...WITH SCHC OVER THE RIDGES.
ON FRIDAY...SHORT RANGE MODELS INDICATE THAT A WEAK MID LEVEL LOW
WILL LINGER NEAR THE GA/FL LINE DURING THE DAY. IN ADDITION...A
POSITIVE TILTED L/W TROF WILL BEGIN TO AMPLIFY ACROSS THE MID
WEST...SLIDING EAST. AT THE SFC...A BROAD AREA OF LOW PRESSURE IS
EXPECTED TO DEVELOP ACROSS THE CAROLINAS AS A SFC FRONT STALLS OVER
THE REGION. FORECAST SOUNDINGS INDICATE THAT MOISTURE WILL SURGE
ACROSS THE REGION...WITH PW VALUES OVER 2 INCHES BY THE AFTERNOON.
THE MOISTURE COMBINED WITH WELL ABOVE AVERAGE HIGH TEMPERATURES
SHOULD YIELD WIDESPREAD MODERATE VALUES OF CAPE. GIVEN THE BROAD
AREA OF LLVL MOISTURE CONVERGENCE...INSTABILITY...AND INCREASING MID
LEVEL FORCING...TSRA COVERAGE WILL INCREASE SIGNIFICANTLY FROM
THURSDAY. I WILL FORECAST LIKELY POPS ACROSS THE MTNS WITH VALUES IN
THE 40 TO 50 RANGE EAST.
&&
.LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/...
AS OF 3 AM WEDNESDAY...SIGNIFICANT PATTERN CHANGE WILL SETTLE OVER
THE REGION THIS WEEKEND AND SHOULD REMAIN THROUGH THE EXTENDED
PERIOD. MODELS INDICATE THAT THE AXIS OF A L/W TROUGH WILL SWEEP
ACROSS THE REGION THIS WEEKEND...WITH A SECONDARY WAVE EXPECTED TO
CROSS THE APPALACHIANS ON TUESDAY. AT THE SFC...THE CENTER OF A
DEEPENING LOW WILL MOVE FROM THE OHIO RIVER VALLEY ON SATURDAY TO
SOUTHERN NY BY SUNDAY EVENING. A COLD FRONT SHOULD PUSH ACROSS THE
REGION LATE SATURDAY AFTERNOON AND EVENING. THE ENVIRONMENT AHEAD OF
THE FRONT WILL FEATURE WIDESPREAD INSTABILITY AND WEAK
SHEAR...POSSIBLY SUPPORTING A BAND OF TSRA SAT AFTERNOON. I WILL
FORECAST CATE COVERAGE NEAR THE TN LINE...WITH GENERALLY LIKELY POPS
ACROSS THE REST OF THE CWA. DRIER AIR WILL BUILD ACROSS THE REGION
ON SUNDAY...RESULTING IN FALLING POP VALUES. I WILL FORECAST
PRIMARILY DIURNAL POPS ACROSS THE REGION MON AND TUES. TEMPERATURES
THROUGH THE EXTENDED ARE FORECAST TO RANGE FROM BELOW NORMAL THIS
WEEKEND TO NEAR NORMAL BY TUESDAY.
&&
.AVIATION /09Z WEDNESDAY THROUGH SUNDAY/...
AT KCLT...EXPECT MAINLY LIGHT SW TO WSW FLOW EARLY THIS MORNING AS A
WEAK FRONT SAGS SOUTH TOWARD THE TERMINAL...WITH FLOW TOGGLING NW
AND THEN NE TODAY BEHIND THE BOUNDARY. PRECIPITATION CHANCES LOOK
RATHER SMALL AROUND THE AIRFIELD GIVEN THE WARM PROFILES ALOFT...BUT
ANY CONVECTION THAT FORMS WILL BE STRONG. VFR CONDITIONS WILL
CONTINUE WITH HIGH BASED CUMULUS FORMING AND BEING TOPPED BY TEMPO
HIGH CLOUD DEBRIS CIGS FROM TIME TO TIME.
ELSEWHERE...CONVECTIVE CHANCES REMAIN GREATEST AT KAVL THIS AFTN DUE
TO TERRAIN FLOW AND LOW LEVEL CONVERGENCE...BUT A TSRA CANNOT BE
RULED OUT ACROSS THE UPSTATE SITES WHERE INSTABILITY WILL BE THE
GREATEST. ANY TSRA WOULD BE QUITE STRONG WITH THE POTENTIAL FOR
GUSTY WINDS GIVEN THE MID LEVEL DRY AIR. EXPECT SFC WINDS TO TOGGLE
NW THEN NE THROUGH THE DAY BEFORE TURNING AROUND THE DIAL TO SE
LATE. THE BEST CHANCE FOR DAYBREAK RESTRICTIONS WILL BE IN THE MTN
VALLEYS...BUT WILL CONFINE THE FOG TO MVFR AT KAVL FOR NOW.
OUTLOOK...SCT DIURNAL TSTM CHANCES WILL INCREASE LATE WEEK INTO THE
WEEKEND AS A FRONT EVENTUALLY APPROACHES FROM THE NW. MORNING
RESTRICTIONS DUE TO FOG AND/OR STRATUS ARE POSSIBLE...PARTICULARLY
WHERE HEAVY RAIN FELL THE PREVIOUS DAY...AND IN THE MOUNTAIN RIVER
VALLEYS.
CONFIDENCE TABLE...
09-15Z 15-21Z 21-03Z 03-06Z
KCLT HIGH 100% HIGH 100% HIGH 100% HIGH 100%
KGSP HIGH 100% HIGH 100% HIGH 100% HIGH 100%
KAVL HIGH 88% HIGH 100% HIGH 100% HIGH 100%
KHKY HIGH 100% HIGH 100% HIGH 100% HIGH 100%
KGMU HIGH 100% HIGH 100% HIGH 100% HIGH 100%
KAND HIGH 91% HIGH 100% HIGH 100% HIGH 100%
THE PERCENTAGE REFLECTS THE NUMBER OF GUIDANCE MEMBERS AGREEING
WITH THE SCHEDULED TAF ISSUANCE FLIGHT RULE CATEGORY. COMPLETE HOURLY
EXPERIMENTAL AVIATION FORECAST CONSISTENCY TABLES AND ENSEMBLE FORECASTS
ARE AVAILABLE AT THE FOLLOWING LINK: (MUST BE LOWER CASE)
WWW.WEATHER.GOV/GSP/AVIATION_TABLES
&&
.CLIMATE...
RECORD MAXIMUM TEMPERATURES FOR THIS WEEK...WITH YEARS IN WHICH THE
VALUES WERE LAST REACHED.
WEDNESDAY JUNE 24...
AVL 94 1952
CLT 102 1930
GSP 100 1952
THURSDAY JUNE 25...
AVL 96 1952
CLT 102 1914
GSP 101 1952
&&
.GSP WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
NC...NONE.
SC...NONE.
&&
$$
SYNOPSIS...NED
NEAR TERM...HG/WJM
SHORT TERM...NED
LONG TERM...NED
AVIATION...HG
CLIMATE...
AREA FORECAST DISCUSSION
NWS GREENVILLE-SPARTANBURG SC
307 AM EDT WED JUN 24 2015
.SYNOPSIS...
STRONG MID LEVEL HIGH PRESSURE WILL PERSIST ACROSS THE REGION
THROUGH THE REMAINDER OF THE WORK WEEK...MAINTAINING WELL ABOVE
NORMAL TEMPERATURES. A BROAD UPPER LEVEL TROF WILL MOVE OVER THE
REGION OVER THE WEEKEND RETURNING TEMPERATURES TO SEASONAL LEVELS BY
SUNDAY AND INCREASING CHANCES FOR WIDESPREAD SHOWERS AND
THUNDERSTORMS. A COOLER AND DRIER PATTERN WILL TAKE SHAPE AFTER A
FRONT PASSES EARLY IN THE WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 250 AM EDT...THE LATEST HRRR RUNS ALLOW LINGERING EARLY
MORNING DECAYING CONVECTION TO PASS MAINLY NE OF THE AREA ALONG THE
FRONTAL BOUNDARY DROPPING SWD...AND ALSO W OF THE AREA WITH
CONVECTION FANNING OUT IN THE BETTER INSTABILITY ACROSS SRN TN AND
INTO THE DEEP SOUTH OVERNIGHT. LITTLE MORE THAN AN ISOLD TO SCT
EARLY MORNING SHRA/TSRA MENTION WILL BE NEEDED ALONG THE SPINE OF
THE SOUTHERN APPALACHIANS.
OTHERWISE...THE WEAK SURFACE FRONTAL BOUNDARY WILL STALL IN THE
FORECAST AREA TODAY AND THEN LIKELY LIFT NORTHWARD AS A WARM FRONT
TONIGHT. THE NUMERICAL MODELS HAVE SURPRISINGLY LITTLE CONVECTION
FIRING OVER THE FORECAST AREA THIS AFTN GIVEN THE BOUNDARY IN THE
REGION. THIS APPEARS TO BE DUE TO WARM PROFILES ALOFT AND NEGATIVE
AREA IN MODEL SOUNDINGS. HOWEVER...SEVERE WEATHER WILL BE A THREAT
WITH ANY TSTMS THAT FORM AS MODERATE OR BETTER CAPE LOOKS LIKELY
ALONG WITH MID LEVEL DRY AIR AND ASSOCIATED THETA E LAPSES YIELDING
SOME MEASURE OF MICROBURST POTENTIAL. THE SRN HALF WILL BE MOST AT
RISK GIVEN THE BOUNDARY LOCATION AND LIKELY SBCAPE VALUES OF 3000 TO
3500 J/KG THERE DURING PEAK HEATING.
TEMPERATURES AND ASSOCIATED HEAT INDEX VALUES WILL BE THE OTHER
ISSUE FOR THE FORECAST TODAY. BL AND 850 TEMPS LOOK COMPARABLE TO
YESTERDAY...BUT SO DOES THE POTENTIAL FOR SOME DEWPOINT MIXING IN
THE WARMEST PIEDMONT SECTIONS. PLUS...THERE COULD BE CONSIDERABLE
DEBRIS CLOUDS AROUND AT TIMES TODAY. WILL KEEP HEAT INDEX VALUES IN
THE SRN PIEDMONT AT 100 TO 104 THIS AFTN. ANTICIPATE ANOTHER VERY
MILD NIGHT WITH PRECIPITATION CHANCES STEADILY WANING WITH THE LOSS
OF HEATING.
&&
.SHORT TERM /THURSDAY THROUGH FRIDAY/...
AS OF 245 AM WEDNESDAY...ON THURSDAY...THE H5 AND H7 RIDGE WILL
REMAIN CENTERED OVER THE DEEP SOUTH. HOWEVER...HEIGHTS SHOULD RISE
FROM THE SOUTH AS THE RIDGE CENTER DRIFTS EAST DURING THE DAY. USING
A BLEND OF PREFERRED GUIDANCE...I WILL FORECAST HIGHS AROUND 90
WITHIN THE MTN VALLEYS TO MID TO HIGH 90S ACROSS THE FOOTHILLS AND
PIEDMONT. A WEST TO EAST FRONT WILL REMAIN ACROSS THE OHIO RIVER
VALLEYS AS A SFC TROF COVERS THE FOOTHILLS AND PIEDMONT. GIVEN THE
SFC PATTERN...LLVL WINDS ARE FORECAST TO REMAIN LIGHT FROM THE WSW.
FORECAST SOUNDINGS REVEAL THAT A SIGNIFICANT LAYER OF CIN WILL
REMAIN AROUND H75...VALUES RANGING FROM 40-60 J/KG. THE LACK OF
FORCING AND LINGERING CAPPING SHOULD FAVOR LITTLE TO NO COVERAGE OF
DEEP CONVECTION ON THURSDAY. I WILL FORECAST DRY CONDITIONS EAST OF
THE MTNS...WITH SCHC OVER THE RIDGES.
ON FRIDAY...SHORT RANGE MODELS INDICATE THAT A WEAK MID LEVEL LOW
WILL LINGER NEAR THE GA/FL LINE DURING THE DAY. IN ADDITION...A
POSITIVE TILTED L/W TROF WILL BEGIN TO AMPLIFY ACROSS THE MID
WEST...SLIDING EAST. AT THE SFC...A BROAD AREA OF LOW PRESSURE IS
EXPECTED TO DEVELOP ACROSS THE CAROLINAS AS A SFC FRONT STALLS OVER
THE REGION. FORECAST SOUNDINGS INDICATE THAT MOISTURE WILL SURGE
ACROSS THE REGION...WITH PW VALUES OVER 2 INCHES BY THE AFTERNOON.
THE MOISTURE COMBINED WITH WELL ABOVE AVERAGE HIGH TEMPERATURES
SHOULD YIELD WIDESPREAD MODERATE VALUES OF CAPE. GIVEN THE BROAD
AREA OF LLVL MOISTURE CONVERGENCE...INSTABILITY...AND INCREASING MID
LEVEL FORCING...TSRA COVERAGE WILL INCREASE SIGNIFICANTLY FROM
THURSDAY. I WILL FORECAST LIKELY POPS ACROSS THE MTNS WITH VALUES IN
THE 40 TO 50 RANGE EAST.
&&
.LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/...
AS OF 3 AM WEDNESDAY...SIGNIFICANT PATTERN CHANGE WILL SETTLE OVER
THE REGION THIS WEEKEND AND SHOULD REMAIN THROUGH THE EXTENDED
PERIOD. MODELS INDICATE THAT THE AXIS OF A L/W TROUGH WILL SWEEP
ACROSS THE REGION THIS WEEKEND...WITH A SECONDARY WAVE EXPECTED TO
CROSS THE APPALACHIANS ON TUESDAY. AT THE SFC...THE CENTER OF A
DEEPENING LOW WILL MOVE FROM THE OHIO RIVER VALLEY ON SATURDAY TO
SOUTHERN NY BY SUNDAY EVENING. A COLD FRONT SHOULD PUSH ACROSS THE
REGION LATE SATURDAY AFTERNOON AND EVENING. THE ENVIRONMENT AHEAD OF
THE FRONT WILL FEATURE WIDESPREAD INSTABILITY AND WEAK
SHEAR...POSSIBLY SUPPORTING A BAND OF TSRA SAT AFTERNOON. I WILL
FORECAST CATE COVERAGE NEAR THE TN LINE...WITH GENERALLY LIKELY POPS
ACROSS THE REST OF THE CWA. DRIER AIR WILL BUILD ACROSS THE REGION
ON SUNDAY...RESULTING IN FALLING POP VALUES. I WILL FORECAST
PRIMARILY DIURNAL POPS ACROSS THE REGION MON AND TUES. TEMPERATURES
THROUGH THE EXTENDED ARE FORECAST TO RANGE FROM BELOW NORMAL THIS
WEEKEND TO NEAR NORMAL BY TUESDAY.
&&
.AVIATION /07Z WEDNESDAY THROUGH SUNDAY/...
AT KCLT...EXPECT MAINLY LIGHT SW TO WSW FLOW EARLY THIS MORNING AS A
WEAK FRONT SAGS SOUTH TOWARD THE TERMINAL...WITH FLOW TOGGLING NW
AND THEN NE TODAY BEHIND THE BOUNDARY. PRECIPITATION CHANCES
CONTINUE TO LOOK SMALL AROUND THE AIRFIELD GIVEN THE WARM PROFILES
ALOFT...BUT ANY CONVECTION THAT FORMS WILL BE STRONG. VFR CONDITIONS
WILL CONTINUE WITH HIGH BASED CUMULUS FORMING AND BEING TOPPED BY
TEMPO HIGH CLOUD DEBRIS CIGS FROM TIME TO TIME.
ELSEWHERE...CONVECTIVE CHANCES REMAIN GREATEST AT KAVL THIS AFTN DUE
TO TERRAIN FLOW AND LOW LEVEL CONVERGENCE...BUT A TSRA CANNOT BE
RULED OUT ACROSS THE UPSTATE SITES WHERE INSTABILITY WILL BECOME THE
GREATEST. ANY TSRA WOULD BE QUITE STRONG WITH THE POTENTIAL FOR
GUSTY WINDS GIVEN THE MID LEVEL DRY AIR. EXPECT SFC WINDS TO TOGGLE
NW THEN NE THROUGH THE DAY BEFORE TURNING AROUND THE DIAL TO SE
LATE. THE BEST CHANCE FOR DAYBREAK RESTRICTIONS WILL BE IN THE MTN
VALLEYS...BUT WILL CONFINE THE FOG TO MVFR AT KAVL FOR NOW.
OUTLOOK...SCT DIURNAL TSTM CHANCES WILL INCREASE LATE WEEK INTO THE
WEEKEND AS A FRONT EVENTUALLY APPROACHES FROM THE NW. MORNING
RESTRICTIONS DUE TO FOG AND/OR STRATUS ARE POSSIBLE...PARTICULARLY
WHERE HEAVY RAIN FELL THE PREVIOUS DAY...AND IN THE MOUNTAIN RIVER
VALLEYS.
CONFIDENCE TABLE...
07-13Z 13-19Z 19-01Z 01-06Z
KCLT HIGH 100% HIGH 100% HIGH 100% HIGH 100%
KGSP HIGH 96% HIGH 100% HIGH 100% HIGH 100%
KAVL HIGH 100% HIGH 95% HIGH 100% HIGH 100%
KHKY HIGH 100% HIGH 100% HIGH 100% HIGH 100%
KGMU HIGH 100% HIGH 100% HIGH 100% HIGH 100%
KAND HIGH 93% HIGH 100% HIGH 100% HIGH 100%
THE PERCENTAGE REFLECTS THE NUMBER OF GUIDANCE MEMBERS AGREEING
WITH THE SCHEDULED TAF ISSUANCE FLIGHT RULE CATEGORY. COMPLETE HOURLY
EXPERIMENTAL AVIATION FORECAST CONSISTENCY TABLES AND ENSEMBLE FORECASTS
ARE AVAILABLE AT THE FOLLOWING LINK: (MUST BE LOWER CASE)
WWW.WEATHER.GOV/GSP/AVIATION_TABLES
&&
.CLIMATE...
RECORD MAXIMUM TEMPERATURES FOR THIS WEEK...WITH YEARS IN WHICH THE
VALUES WERE LAST REACHED.
WEDNESDAY JUNE 24...
AVL 94 1952
CLT 102 1930
GSP 100 1952
THURSDAY JUNE 25...
AVL 96 1952
CLT 102 1914
GSP 101 1952
&&
.GSP WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
NC...NONE.
SC...NONE.
&&
$$
SYNOPSIS...LEV/NED
NEAR TERM...HG/WJM
SHORT TERM...NED
LONG TERM...NED
AVIATION...HG
CLIMATE...
AREA FORECAST DISCUSSION
NWS GREENVILLE-SPARTANBURG SC
229 AM EDT WED JUN 24 2015
.SYNOPSIS...
STRONG MID LEVEL HIGH PRESSURE WILL PERSIST ACROSS THE REGION
THROUGH THE REMAINDER OF THE WORK WEEK...MAINTAINING WELL ABOVE
NORMAL TEMPERATURES. A BROAD UPPER LEVEL TROF WILL MOVE OVER THE
REGION OVER THE WEEKEND RETURNING TEMPERATURES TO SEASONAL LEVELS BY
SUNDAY AND INCREASING CHANCES FOR WIDESPREAD SHOWERS AND
THUNDERSTORMS. A COOLER AND DRIER PATTERN WILL TAKE SHAPE AFTER A
FRONT PASSES EARLY IN THE WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 210 AM EDT...THE LATEST HRRR RUNS ALLOW CONVECTION TO PASS
MAINLY NE OF THE AREA ALONG THE FRONTAL BOUNDARY DROPPING SWD...AND
ALSO W OF THE AREA WITH CONVECTION FANNING OUT IN THE BETTER
INSTABILITY ACROSS SRN TN AND INTO THE DEEP SOUTH OVERNIGHT. LITTLE
MORE THAN AN ISOLD TO SCT EARLY MORNING SHRA/TSRA MENTION WILL BE
NEEDED ALONG THE SPINE OF THE SOUTHERN APPALACHIANS.
OTHERWISE...A SURFACE FRONTAL BOUNDARY WILL STALL IN THE FORECAST
AREA TODAY AND THEN LIKELY LIFT NORTHWARD AS A WARM FRONT TONIGHT.
THE NUMERICAL MODELS HAVE SURPRISINGLY LITTLE CONVECTION FIRING OVER
THE FORECAST AREA THIS AFTN GIVEN THE BOUNDARY IN THE REGION. THIS
APPEARS TO BE DUE TO WARM PROFILES ALOFT AND NEGATIVE AREA IN MODEL
SOUNDINGS. HOWEVER...SEVERE WEATHER WILL BE A THREAT WITH ANY TSTMS
THAT FORM AS MODERATE OR BETTER CAPE LOOKS LIKELY ALONG WITH SOME
MID LEVEL DRY AIR AND ASSOCIATED THETA E LAPSES YIELDING SOME
MICROBURST POTENTIAL. THE SRN HALF WILL BE MOST AT RISK GIVEN THE
BOUNDARY LOCATION AND LIKELY SBCAPE VALUES OF 3000 TO 3500 J/KG
THERE DURING PEAK HEATING.
TEMPERATURES AND ASSOCIATED HEAT INDEX VALUES WILL BE THE OTHER
ISSUE FOR THE FORECAST TODAY. BL AND 850 TEMPS LOOK COMPARABLE TO
YESTERDAY...BUT SO DOES THE POTENTIAL FOR SOME DEWPOINT MIXING IN
THE WARMEST PIEDMONT SECTIONS. PLUS...THERE COULD BE CONSIDERABLE
DEBRIS CLOUDS AROUND AT TIMES TODAY. WILL KEEP HEAT INDEX VALUES IN
THE SRN PIEDMONT AT 100 TO 104 THIS AFTN. ANTICIPATE ANOTHER VERY
MILD NIGHT WITH PRECIPITATION CHANCES STEADILY WANING WITH THE LOSS
OF HEATING.
&&
.SHORT TERM /THURSDAY THROUGH FRIDAY/...
AS OF 205 PM TUESDAY...SOME SUBTLE CHANGES OCCUR BY THE END OF THE
SHORT TERM PERIOD WHICH WILL PORTEND AN EVENTUAL END TO THE
ABNORMALLY HOT CONDITIONS THAT HAVE PREVAILED. HOWEVER PRIOR TO
THAT...THE UPPER HIGH OVER THE TN VALLEY WILL CONTINUE TO NOSE
EASTWARD INTO THE SOUTHERN APPALACHIANS AND WESTERN CAROLINAS WED
NIGHT AND THEN SLOWLY WEAKEN AS IT SLIDES EASTWARD TO THE COAST BY
EARLY FRIDAY. THIS IS IN REPONSE TO A SHORT WAVE TROUGH DIGGING SE
INTO THE MIDWEST WHICH WILL BEGIN LOWERING HEIGHTS ACROSS THE SE
STATES DURING FRIDAY.
AT THE SURFACE...THE WEAK FRONTAL BOUNDARY IS FORECAST TO LIE FROM
NEAR CLT...SW THROUGH GREENVILLE INTO NE GA WEDNESDAY EVENING. BOTH
THE NAM AND GFS USE THIS BOUNDARY TO FIRE UP SOME WED EVENING
CONVECTION. HENCE...WILL NEED TO ADDRESS THIS POSSIBILITY WITH SOME
SCT TYPE POPS. BOTH THE NAM AND GFS ARE IN AGREEMENT THAT CONVECTIVE
CHANCES WILL BE SUPRESSED ON THURSDAY AS THE WEAKENING UPPER HIGH
SLIDES EAST INTO THE AREA. THE SYNOPTIC SUBSIDENCE ASSOCIATED WITH
THE UPPER HIGH SHOULD SERVE TO LIMIT CONVECTION TO THE MOUNTAINS AND
THAT MAY BE JUST ALONG THE BLUE RIDGE WHERE BEST DIFFERENTIAL
HEATING SETS UP. MODEL SOUNDINGS INDICATE CONSIDERABLE CINH TO
OVERCOME SO WILL LIMIT POPS TO WIDELY SCT OVER THE MOUNTAINS. IT
WILL REMAIN QUITE HOT ON THURSDAY AND WILL TREND MAX TEMPERATURES
TOWARD THE UPPER RANGE OF GUIDANCE WHICH MEANS MID TO UPPER 90S
OUTSIDE THE MOUNTAINS.
ON FRIDAY AS HEIGHTS BEGIN TO LOWER...WE SHOULD SEE A NOTABLE UPTICK
IN CONVECTIVE COVERAGE. THEREFORE...WILL FEATURE SCT-NUMEROUS TYPE
POPS WITH THE BEST COVERAGE OVER THE MOUNTAINS AND WESTERN AREAS.
THE INCREASED CONVECTIVE COVERAGE SHOULD SERVE TO KEEP MAXIMUM
TEMPERATURES IN CHECK SOMEWHAT. HOWEVER...IT WILL STILL BE QUITE
WARM WITH THE HOTTEST TEMPS OVER THE I-77 CORRIDOR WHERE MID 90S ARE
IN THE FORECAST.
&&
.LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/...
AS OF 230 PM TUESDAY...THE BEGINNING OF THE MEDIUM RANGE FEATURES A
PRONOUNCED TRANSITION IN THE SYNOPTIC PATTERN OVER THE CONUS. AN H5
TROUGH WILL DIG DEEP INTO THE SOUTHEAST ON SATURDAY...WITH A TRAIL
OF SURFACE LOWS ROUNDING THE BASE OF THE TROUGH AND TRACKING THROUGH
THE OHIO RIVER VALLEY. A FRONTAL BOUNDARY ASSOCIATED WITH A CLOSED
SURFACE LOW ON THAT TRACK WILL APPROACH THE FORECAST AREA SATURDAY
AND EARLY SUNDAY...BRINGING LIKELY POPS TO THE ENTIRE CWA. THE FRONT
WILL PASS THE AREA BY LATE SUNDAY. THERE IS SOME DISCREPANCY IN THE
AMOUNT OF CLEARING BEHIND THE FRONT...WITH THE ECMWF MAINTAINING
MORE MOISTURE AFTER THE FRONTAL PASSAGE THAN THE DRY GFS. THE
PATTERN DOES LOOK TO DRY OUT SOMEWHAT MONDAY AND TUESDAY AS A
SURFACE HIGH BUILDS OVER THE SOUTHEAST...WITH POPS PEAKING DIURNALLY
YET REMAINING JUST BELOW CLIMO THROUGH THE END OF THE EXTENDED
PERIOD.
THE EXTENDED PERIOD WILL BEGIN WITH MAX TEMPS JUST ABOVE CLIMO...AND
WILL TAPER TO NEAR AVEAGE OVER THE WEEKEND. TEMPS WILL BE A CATEGORY
OR TWO COOLER THAN THE SHORT TERM ON MONDAY AND TUESDAY AFTER THE
FRONTAL PASSAGE.
&&
.AVIATION /07Z WEDNESDAY THROUGH SUNDAY/...
AT KCLT...EXPECT MAINLY LIGHT SW TO WSW FLOW EARLY THIS MORNING AS A
WEAK FRONT SAGS SOUTH INTO THE REGION...WITH FLOW TOGGLING NW AND
THEN NE TODAY BEHIND THE BOUNDARY. PRECIPITATION CHANCES CONTINUE TO
LOOK SMALL AROUND THE AIRFIELD GIVEN THE WARM PROFILES ALOFT...BUT
ANY CONVECTION THAT FORMS WILL BE STRONG. VFR CONDITIONS WILL
CONTINUE WITH HIGH BASED CUMULUS FORMING AND BEING TOPPED BY TEMPO
HIGH CLOUD DEBRIS CIGS FROM TIME TO TIME.
ELSEWHERE...CONVECTIVE CHANCES REMAIN GREATEST AT KAVL THIS AFTN DUE
TO TERRAIN FLOW AND LOW LEVEL CONVERGENCE...BUT A TSRA CANNOT BE
RULED OUT ACROSS THE UPSTATE SITES WHERE INSTABILITY WILL BECOME THE
GREATEST. ANY TSRA WOULD BE QUITE STRONG WITH THE POTENTIAL FOR
GUSTY WINDS GIVEN THE MID LEVEL DRY AIR. EXPECT SFC WINDS TO TOGGLE
NW THEN NE THROUGH THE DAY BEFORE TURNING AROUND THE DIAL TO SE
LATE. THE BEST CHANCE FOR DAYBREAK RESTRICTIONS WILL BE IN THE MTN
VALLEYS...BUT WILL CONFINE IT TO MVFR AT KAVL FOR NOW.
OUTLOOK...SCT DIURNAL TSTM CHANCES WILL INCREASE LATE WEEK INTO THE
WEEKEND AS A FRONT EVENTUALLY APPROACHES FROM THE NW. MORNING
RESTRICTIONS DUE TO FOG AND/OR STRATUS ARE POSSIBLE...PARTICULARLY
WHERE HEAVY RAIN FELL THE PREVIOUS DAY...AND IN THE MOUNTAIN RIVER
VALLEYS.
CONFIDENCE TABLE...
06-12Z 12-18Z 18-24Z 00-06Z
KCLT HIGH 100% HIGH 100% HIGH 100% HIGH 100%
KGSP HIGH 100% HIGH 100% HIGH 100% HIGH 100%
KAVL HIGH 100% HIGH 91% HIGH 100% HIGH 100%
KHKY HIGH 100% HIGH 100% HIGH 100% HIGH 100%
KGMU HIGH 100% HIGH 100% HIGH 100% HIGH 100%
KAND HIGH 94% HIGH 100% HIGH 100% HIGH 100%
THE PERCENTAGE REFLECTS THE NUMBER OF GUIDANCE MEMBERS AGREEING
WITH THE SCHEDULED TAF ISSUANCE FLIGHT RULE CATEGORY. COMPLETE HOURLY
EXPERIMENTAL AVIATION FORECAST CONSISTENCY TABLES AND ENSEMBLE FORECASTS
ARE AVAILABLE AT THE FOLLOWING LINK: (MUST BE LOWER CASE)
WWW.WEATHER.GOV/GSP/AVIATION_TABLES
&&
.CLIMATE...
RECORD MAXIMUM TEMPERATURES FOR THIS WEEK...WITH YEARS IN WHICH THE
VALUES WERE LAST REACHED.
WEDNESDAY JUNE 24...
AVL 94 1952
CLT 102 1930
GSP 100 1952
THURSDAY JUNE 25...
AVL 96 1952
CLT 102 1914
GSP 101 1952
&&
.GSP WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
NC...NONE.
SC...NONE.
&&
$$
SYNOPSIS...LEV
NEAR TERM...HG/WJM
SHORT TERM...LG
LONG TERM...JP/LEV
AVIATION...HG
CLIMATE...
AREA FORECAST DISCUSSION...UPDATED
NWS NASHVILLE TN
1154 PM CDT TUE JUN 23 2015
.UPDATE...FOR 06Z AVIATION DISCUSSION.
&&
.AVIATION UPDATE...06Z AVIATION DISCUSSION.
SFC FRONT IS EXPECTED TO MOVE S OF MID STATE BY 24/12Z...WHICH WILL USHER IN
SOME DRIER AIR TO THE AREA. WITH CONVECTION THIS EVENING NOW HAVING MOVED
S OF TERMINALS..SOME MVFR FOG INDUCED VSBYS/CEILINGS POSSIBLE CKV/BNA AROUND
24/06Z-24/15Z PER SUITABLE DEWPOINT DEPRESSIONS AND FROM RAINFALL FROM THIS
EVENING`S CONVECTION ALONG WITH LOW LEVEL MOISTURE POOLING POTENTIAL AND
SLOWLY CLRING SKIES APPROACHING 24/12Z. WITH DRIER AIR WORKING INTO MID
STATE THRU 25/06Z...BELIEVE POTENTIAL FOR ISO SHWRS/TSTMS WILL BE OVERALL
LESS THAN THIS AFTERNOON`S COVERAGE AND WILL MENTION ONLY SCT CU...SCT/BKN
AC...AND SCT/BKN CI THRU 25/02Z...WITH BKN CI THRU 25/06Z.
&&
.PREV DISCUSSION... /ISSUED 939 PM CDT TUE JUN 23 2015/
UPDATE...
18Z GFS RUN SHOWING UPPER HIGH OVER EASTERN OK WITH THE RIDGE AXIS
EXTENDING ESE ACROSS NRN AL. CURVATURE AND SHEAR NOTED UPSTREAM
WITH VORT MAX NOW MOVING THROUGH NRN MIDDLE TN. PVA IS CURRENTLY
ACROSS SOUTHERN MIDDLE TN AND IS COUPLING WITH DIVERGENCE
ALOFT...JUST NORTH OF THE RIDGE AXIS. MEAN 700-500MB FLOW IS
RATHER WEAK AND THUS STORMS ARE SLOW MOVERS. PWATS ARE STILL
RATHER HIGH AND ISOL AREAS OF FLOODING IS ONGOING.
FOR THE UPDATE...WILL INCREASE POPS ACROSS SOUTHWESTERN AREAS AND
THE SOUTHERN AND CENTRAL PLATEAU...PER ONGOING CONVECTION. WILL
ALSO MAKE A SLIGHT UPWARD TWEAK WITH THE SKY GRIDS.
PREV DISCUSSION... /ISSUED 801 PM CDT TUE JUN 23 2015/
UPDATE...
WILL ISSUE A QUICK UPDATE AND INCREASE POPS INTO THE CHANCE
CATEGORY AREA WIDE BETWEEN NOW AND 03Z. ALSO...WILL INCLUDE FOG
ACROSS THE PLATEAU FOR THE AFT MIDNIGHT PERIOD.
WILL ALLOW THE SLIGHT CHANCE TO COVER THE PRECIP CHANCES FROM 03Z
TO 06Z. THE FRONT IS APPROACHING THE KY/TN BORDER AT THIS TIME. IT
IS QUITE WEAK AND THE UPPER RIDGING BUILDING IN FROM THE WEST IS
STRENGTHENING. THEREFORE...THIS ACTIVITY SHOULD DIE OUT AS THE
NIGHT PROGRESSES. HRRR AND ISC BOTH CONCUR.
UPDATE OUT SHORTLY.
PREV DISCUSSION... /ISSUED 703 PM CDT TUE JUN 23 2015/
UPDATE...FOR 00Z AVIATION DISCUSSION.
AVIATION UPDATE...00Z AVIATION DISCUSSION.
SFC FRONT IS EXPECTED TO MOVE S OF MID STATE BY 24/12Z...WHICH WILL USHER IN
SOME DRIER AIR TO THE AREA. WITH CONVECTION THIS EVENING NOW HAVING MOVED
S OF TERMINALS..SOME MVFR FOG INDUCED VSBYS/CEILINGS POSSIBLE CKV/BNA AROUND
24/06Z-24/15Z PER SUITABLE DEWPOINT DEPRESSIONS AND FROM RAINFALL FROM THIS
EVENING`S CONVECTION ALONG WITH LOW LEVEL MOISTURE POOLING POTENTIAL AND
SLOWLY CLRING SKIES APPROACHING 24/12Z. WITH DRIER AIR WORKING INTO MID
STATE THRU 25/06Z...BELIEVE POTENTIAL FOR ISO SHWRS/TSTMS WILL BE OVERALL
LESS THAN THIS AFTERNOON`S COVERAGE AND WILL MENTION ONLY SCT CU...SCT/BKN
AC...AND SCT/BKN CI THRU 25/02Z...WITH BKN CI THRU 25/06Z.
PREV DISCUSSION.../ISSUED 404 PM CDT TUE JUN 23 2015/
DISCUSSION...
TEMPS AND DEWPOINTS SOARING AGAIN THIS AFTERNOON...HEAT INDICES
WILL BE BETWEEN 100 AND 104 TODAY. A FEW STORMS HAVE BEEN MOVING
ACROSS NORTHERN KENTUCKY THIS AFTERNOON AHEAD OF A COLD FRONT
SLOWLY MAKING ITS WAY THROUGH THE OHIO VALLEY. MODELS INDICATE IT
WILL MAKE IT FAR ENOUGH SOUTH THIS EVENING TO BRING A FEW ISOLATED
SHOWERS AND THUNDERSTORMS TO MIDDLE TENNESSEE...WITH THE BEST
CHANCE FOR PRECIP IN THE NORTHEAST COUNTIES. SOME STORMS MAY
BECOME STRONG WITH GUSTY WINDS AND HEAVY RAIN. WINDS WILL SHIFT
OUT OF THE NORTH OVERNIGHT TONIGHT BRINGING IN SLIGHTLY DRIER
AIR...WHICH LOOKS TO KEEP OUR DEWPOINTS LOW ENOUGH ON WEDNESDAY TO
ALLOW US TO ONCE AGAIN AVOID A HEAT ADVISORY. HOWEVER, THE HEAT
INDICES ARE STILL EXPECTED TO BE IN THE 100 TO 105 RANGE FOR OUR
SOUTHERN COUNTIES...SO WE`LL CONTINUE TO KEEP AN EYE ON DEWPOINTS
AND TEMPS THROUGHOUT THE DAY IN THAT AREA. WITH WEDNESDAY`S DRIER
AIR COMES LOWER POPS WITH ONLY AN AFTERNOON THUNDERSTORM OR TWO
EXPECTED.
DEWPOINTS RECOVER ON THURSDAY AS A SURFACE HIGH PASSES NORTHEAST
OF THE TENNESSEE VALLEY STIRRING UP A LIGHT SOUTHERLY FLOW AND AN
INCREASE IN MOISTURE OVER MIDDLE TENNESSEE. CONSEQUENTLY EXPECT A
FEW MORE SHOWERS AND THUNDERSTORMS THURSDAY AFTERNOON AND EVENING
ALONG WITH HEAT INDICES AROUND ADVISORY CRITERIA...105 TO 108.
WILL HOLD OFF ON ISSUING AN ADVISORY AT THIS TIME UNTIL CONFIDENCE
IS HIGHER.
PRECIP CHANCES INCREASE AS WE HEAD INTO FRIDAY. AN UPPER TROUGH
WILL DEEPEN OVER THE EASTERN U.S. AND SWING A COLD FRONT THROUGH
THE TENNESSEE VALLEY EARLY SATURDAY MORNING. THIS WILL ALLOW FOR
A GOOD FOCUSING MECHANISM FOR THUNDERSTORM DEVELOPMENT. FRIDAY
AFTERNOON INSTABILITY IS HIGH ENOUGH FOR THUNDERSTORM
DEVELOPMENT...HOWEVER THE FRONT WILL BE LOCATED TO THE NORTH OF
THE CWA DURING THIS TIME...SO ANY STORMS WILL LIKELY SPARK DUE TO
AFTERNOON HEATING. ALONG WITH THE LACK OF A FOCUSING
MECHANISM...ORGANIZATION MAY BE LIMITED BY BULK SHEAR VALUES
LESS THAN 30KTS...HOWEVER SOME SEVERE STORMS WILL STILL BE
POSSIBLE WITH THE AMOUNT OF INSTABILITY IN PLACE. PWATS ARE
IMPRESSIVE DURING THIS TIME FRAME WITH VALUES OF 1.9 TO 2.00
INCHES STILL INDICATED ON BOTH THE NAM AND THE GFS...SO EXPECTING
STRONG...POSSIBLY SEVERE STORMS WITH HEAVY RAINFALL FRIDAY
AFTERNOON AND EVENING.
AS THE FRONT APPROACHES ON SATURDAY MORNING BULK SHEAR VALUES
INCREASE TO AROUND 40KTS. COULD SEE A SPIKE IN THUNDERSTORM
ACTIVITY EARLY SATURDAY MORNING ALONG THE FRONTAL BOUNDARY THEN
COOLER TEMPS DURING THE AFTERNOON WITH MOSTLY CLOUDY SKIES BEHIND
THE FRONT. CONDITIONS DRY OUT GOING INTO SUNDAY AS THE PREVIOUS
SYSTEM CONTINUES OFF TO THE EAST AND LEAVES THE MID STATE WITH
MUCH MORE PLEASANT DEWPOINTS AND HIGH TEMPERATURES. SUNDAY LOOKS
TO BE A GREAT DAY TO GET OUTSIDE AND ENJOY TEMPERATURES AROUND 80
WITH DEWPOINTS IN THE LOW 60S. TEMPERATURES GRADUALLY WARM DURING
THE FIRST HALF OF THE WORK WEEK NEXT WEEK AS A WEAK SURFACE HIGH
MOVES ACROSS THE TENNESSEE VALLEY. A CHANCE OF THUNDERSTORMS
CREEPS INTO THE FORECAST BY TUESDAY.
PREV DISCUSSION... /ISSUED 108 PM CDT TUE JUN 23 2015/
AVIATION UPDATE...
SURFACE FRONT JUST NORTH OF THE OHIO RIVER WILL MOVE SOUTHWARD AS
WE GO THROUGH THE AFTERNOON AND INTO TONIGHT. AM LOOKING FOR A LINE
OF CONVECTION TO FIRE OFF ALONG THE OHIO RIVER 20Z-21Z TIME FRAME
AND SINK SOUTHWARD WITH THE LEADING EDGE ALONG THE TENNESSEE/KENTUCKY
BORDER AROUND 00Z AND CONTINUE SOUTHWARD INTO MIDDLE TENNESSEE DURING
THE EVENING. FOR NOW WILL RUN VICINITY THUNDERSTORMS AT TERMINALS
BUT WILL UPDATE ONCE LINE DEVELOPS AND TRY AND TIME IT A LITTLE
BETTER. ALSO...LOOKING FOR SOME LATE NIGHT FOG.
&&
.PRELIMINARY POINT TEMPS/POPS...
NASHVILLE 74 92 73 96 / 30 20 10 20
CLARKSVILLE 72 89 72 94 / 30 20 10 10
CROSSVILLE 70 86 68 90 / 40 20 10 20
COLUMBIA 74 93 73 97 / 30 20 10 20
LAWRENCEBURG 74 93 73 95 / 50 20 10 20
WAVERLY 73 91 73 95 / 30 20 10 20
&&
.OHX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
31
AREA FORECAST DISCUSSION
NWS MEMPHIS TN
1124 PM CDT TUE JUN 23 2015
.UPDATE...
UPDATED TO ADD 06Z AVIATION DISCUSSION.
&&
.PREV DISCUSSION... /ISSUED 1022 PM CDT TUE JUN 23 2015/
UPDATE...EVENING UPDATE
IT NOW LOOKS MORE LIKELY THAT THUNDERSTORMS WILL CONTINUE
OVERNIGHT PUSHING SOUTH ACROSS MOST IF NOT ALL OF THE MIDSOUTH.
ADJUSTED POPS ACCORDINGLY. STORMS WILL MAINLY IMPACT WEST
TENNESSEE AND NORTH MISSISSIPPI...BUT CANNOT BE RULED OUT
ANYWHERE. FREQUENT LIGHTENING AND VERY HEAVY RAINFALL CAN BE
EXPECTED. LOCALIZED FLOODING IS POSSIBLE. WIDESPREAD SEVERE
WEATHER IS NOT ANTICIPATED AT THIS TIME.
30
PREV DISCUSSION... /ISSUED 719 PM CDT TUE JUN 23 2015/
UPDATE...EVENING UPDATE.
DISCUSSION...
INCREASED POPS ACROSS WEST TENNESSEE...THE MISSOURI BOOTHEEL AND
NORTHEAST ARKANSAS. DON`T THINK THERE IS ANY REAL SEVERE THREAT
BUT LOCALLY HEAVY RAIN AND FREQUENT LIGHTNING IS LIKELY. STORMS
SHOULD DIMINISH IN BOTH INTENSITY AND COVERAGE AFTER SUNSET.
PREV DISCUSSION... /ISSUED 623 PM CDT TUE JUN 23 2015/
CURRENTLY...STRONG UPPER RIDGE EXTENDS FROM THE SOUTHERN PLAINS
INTO THE MIDSOUTH. MEANWHILE A WEAK COLD FRONT HAS PUSHED INTO
SOUTHERN MISSOURI AND WESTERN KY...JUST NORTH OF THE MIDSOUTH.
VERY WARM AIR HAS PUSHED INTO THE MIDSOUTH WITH TEMPS IN THE MID
90S ACROSS MUCH OF THE AREA. SURFACE DEWPOINTS ARE POOLING ACROSS
THE REGION...SOUTH OF THE COLD FRONT...WITH READINGS IN THE MID
TO SOMETIMES UPPER 70S. THIS IS CREATING HEAT INDEX VALUES ABOVE
105 ACROSS MUCH OF THE MIDSOUTH. HAVE EXPANDED THE HEAT ADVISORY
TO COVER MOST OF THE MIDSOUTH THIS AFTERNOON INTO WEDNESDAY.
THE HRRR HAS BEEN TRYING TO DEVELOP CONVECTION ALONG THE WEAK COLD
FRONT TO THE NORTH FOR THE LAST FEW HOURS BUT IT HAS NOT HAPPENED
YET. GIVEN THE WEAK CAP AND SBCAPES AROUND 5000 J/KG THERE IS
STILL THE POSSIBILITY OF ISOLATED STORMS DEVELOPING OVER THE NEXT
FEW HOURS.
TONIGHT...ANY CONVECTION WILL DISSIPATE BY 02Z OR SO WITH MOSTLY
CLEAR SKIES AND WARM TEMPERATURES OVERNIGHT. LOWS IN THE 70S.
WEDNESDAY...ANOTHER VERY HOT AND HUMID DAY WITH THE UPPER RIDGE
CENTERED OVER THE AREA. EXPECT HIGHS IN THE MID 90S AND DEWPOINTS
IN THE MID 70S. THE HEAT ADVISORY HAS BEEN EXTENDED THROUGH 7 PM
THURSDAY FOR MOST OF THE MIDSOUTH FOR HEAT INDICES EXCEEDING 105
DEGREES WEDNESDAY AFTERNOON. AN ISOLATED AFTERNOON STORM COULD
OCCUR ANYWHERE BUT THE BEST CHANCE WILL PROBABLY BE ACROSS NORTH
MISSISSIPPI.
THURSDAY...THE UPPER RIDGE WEAKENS A BIT ON THURSDAY BUT STILL
HOT AND HUMID. HEAT ADVISORIES MAY NEED TO BE EXTENDED. STILL VERY
WARM AIRMASS ACROSS THE REGION WITH 925MB TEMPS OF 28C ACROSS MUCH
OF THE AREA. MODELS ARE POINTING TOWARD INCREASING MOISTURE MOVING
UP FROM THE GULF WITH BETTER CHANCES OF AFTERNOON SHOWERS AND
THUNDERSTORMS ACROSS NORTH MISSISSIPPI.
FRIDAY AND SATURDAY...MAJOR PATTERN SHIFT AS THE UPPER RIDGE
BREAKS DOWN AND A DEEP UPPER TROF DEVELOPS OVER THE EASTERN U.S.
A COLD FRONT WILL PUSH THROUGH THE AREA FRIDAY INTO SATURDAY
MORNING WITH NUMEROUS SHOWERS AND THUNDERSTORMS. A FEW STRONG TO
SEVERE STORMS ARE POSSIBLE DURING THIS PERIOD. MUCH COOLER AND
DRIER WEATHER WILL SETTLE OVER THE REGION LATER SATURDAY INTO
EARLY NEXT WEEK AS THE REGION REMAINS UNDER THE INFLUENCE OF THE
UNSEASONABLE DEEP UPPER TROF.
SJM
&&
.AVIATION...
06Z TAF CYCLE
SHOWERS AND THUNDERSTORMS WILL AFFECT TUP THROUGH 24/08Z.
OTHERWISE...SHORT TERM TRENDS SUGGEST A WEAK SURFACE BOUNDARY AND
LEFTOVER OUTFLOW BOUNDARIES FROM TONIGHT/S CONVECTIVE ACTIVITY MAY
INTERACT WITH AN UNSTABLE ATMOSPHERE TO TRIGGER REDEVELOPMENT OF SHOWERS
AND THUNDERSTORMS ACROSS TAF SITES...PREDOMINANTLY AT
MKL...TUP...AND MEM MAINLY AFTER 24/17Z. TEMPORARY IFR CONDITIONS
POSSIBLE WITHIN THUNDERSTORMS. OTHERWISE...VFR CONDITIONS EXPECTED
TO PERSIST THROUGH MUCH OF THE PERIOD. LIGHT W/NW WINDS WILL VEER
N ON WEDNESDAY.
CJC
&&
.MEG WATCHES/WARNINGS/ADVISORIES...
AR...HEAT ADVISORY FROM NOON TO 7 PM CDT WEDNESDAY FOR CLAY-CRAIGHEAD-
CRITTENDEN-CROSS-GREENE-LAWRENCE-LEE AR-MISSISSIPPI-
PHILLIPS-POINSETT-RANDOLPH-ST. FRANCIS.
MO...HEAT ADVISORY FROM NOON TO 7 PM CDT WEDNESDAY FOR DUNKLIN-
PEMISCOT.
MS...HEAT ADVISORY FROM NOON TO 7 PM CDT WEDNESDAY FOR ALCORN-BENTON
MS-CALHOUN-CHICKASAW-COAHOMA-DESOTO-ITAWAMBA-LAFAYETTE-LEE
MS-MARSHALL-MONROE-PANOLA-PONTOTOC-PRENTISS-QUITMAN-
TALLAHATCHIE-TATE-TIPPAH-TISHOMINGO-TUNICA-UNION-YALOBUSHA.
TN...HEAT ADVISORY FROM NOON TO 7 PM CDT WEDNESDAY FOR CHESTER-
CROCKETT-DYER-FAYETTE-HARDEMAN-HARDIN-HAYWOOD-LAKE-
LAUDERDALE-MADISON-MCNAIRY-OBION-SHELBY-TIPTON.
&&
$$
AREA FORECAST DISCUSSION...UPDATED
NWS AUSTIN/SAN ANTONIO TX
110 AM CDT WED JUN 24 2015
.UPDATE...
PLEASE SEE THE 06Z AVIATION DISCUSSION BELOW.
&&
.AVIATION...
LITTLE CHANGES HAVE BEEN MADE TO THE ONGOING AVIATION FORECASTS.
THE LATEST RADAR DATA DOES SHOW SOME CONVECTION ACROSS THE WESTERN
HILL COUNTRY...SOUTHERN EDWARDS PLATEAU AND RIO GRANDE PLAINS
EARLY THIS MORNING. THIS ACTIVITY IS EXPECTED TO REMAIN TOO
ISOLATED TO MENTION IN THE LATEST FORECAST. OTHERWISE...LOW CLOUDS
WILL CONTINUE TO DEVELOP OVERNIGHT...LEADING TO MVFR AND IFR
CONDITIONS THROUGH ROUGHLY 16Z. CLOUDS WILL LIFT WITH VFR EXPECTED
FOR TOMORROW AFTERNOON.
&&
.PREV DISCUSSION... /ISSUED 1124 PM CDT TUE JUN 23 2015/
UPDATE...
HAVE MADE A QUICK PRE-MORNING PACKAGE UPDATE TO THE ONGOING
FORECAST BASED ON CURRENT RADAR TRENDS AND RECENT RUNS OF THE
HRRR. THE HRRR SUGGESTS THAT THE VERY ISOLATED SHOWERS THAT ARE
CURRENTLY ONGOING FROM COMSTOCK...EAST TO HONDO...AND NORTH TO
LLANO WILL CONTINUE THROUGH THE EARLY MORNING HOURS. HAVE ADDED
SLIGHT CHANCE POPS TO THE WESTERN HILL COUNTRY...EDWARDS
PLATEAU...AND RIO GRANDE PLAINS. HAVE ALSO RETRENDED HOURLY GRIDS.
PREV DISCUSSION... /ISSUED 543 PM CDT TUE JUN 23 2015/
UPDATE... /SLIGHT ADJUSTMENT TO EVENING POPS/
SOME POPS WERE ADDED DEEPER INTO THE HILL COUNTRY TO ACCOUNT FOR
SOME SEA-BREEZE ENHANCED STREAMER CONVECTION...AND WERE RAISED TO
30 PERCENT WHERE SOME CLUSTERS HAVE FORMED OVER THE RIO GRANDE
PLAINS. RAPID REFRESH MODELS STILL SHOW A WEAKENING TREND WITH
THE LOSS OF DAYTIME HEATING...SO THE AFTERNOON FORECAST PACKAGE
REMAINS ON TRACK FOR THE REST OF TONIGHT.
PREV DISCUSSION... /ISSUED 233 PM CDT TUE JUN 23 2015/
SHORT TERM (TONIGHT THROUGH WEDNESDAY NIGHT)...
STARTING TO SEE MORE EFFECTS FROM THE UPPER RIDGE TODAY AND THE
OVERALL COVERAGE OF SHOWERS AND THUNDERSTORMS IS LOWER. WE DO
HAVE A FEW STORMS ACROSS THE SOUTHERN COUNTIES...BUT THIS IS NOT
ACCOUNTING FOR MUCH RAINFALL. SHOULD SEE THIS ACTIVITY LINGER FOR
THE NEXT SEVERAL HOURS BEFORE DISSIPATING WITH THE LOSS OF DAYTIME
HEATING. WILL CARRY 20 POPS AFTER 00Z FOR VAL VERDE COUNTY AS
HIGH-RES MODELS ARE HINTING AT SOME ACTIVITY REMAINING CLOSER TO
THE DEPARTING UPPER LOW. TOMORROW SHOULD BE SIMILAR TO TODAY WITH
20-40 POPS ACROSS THE SOUTHERN AND SOUTHEASTERN CWA FOR ANY
ACTIVITY ASSOCIATED WITH THE AFTERNOON SEA BREEZE. HIGHS TOMORROW
WILL BE NEAR 90 DEGREES AND WITH AFTERNOON DEWPOINTS REMAINING IN
THE LOW 70S...HEAT INDICES WILL REACH THE UPPER 90S.
LONG TERM (THURSDAY THROUGH TUESDAY)...
THURSDAY SHOULD CONTINUE TO SAME FORECAST AS THE PREVIOUS COUPLE
OF DAYS. WE COULD SEE THE BEST DAY FOR SEA BREEZE ACTIVITY AS
LOW-LEVEL WINDS ARE A BIT LESS AND SHOULD PROMOTE A BIT MORE
COVERAGE OF SHOWERS AND STORMS. THE ATMOSPHERE SHOULD TEMPORARILY
DRY OUT A BIT FRIDAY AND WE SHOULD NOT SEE MUCH ACTIVITY.
THE FOCUS OF THE REMAINING FORECASTS SHIFTS TO A POSSIBLE COLD
FRONT AFFECTING THE AREA AND INCREASING RAIN CHANCES SATURDAY
NIGHT THROUGH TUESDAY. A STRONG RIDGE WILL AMPLIFY ACROSS THE
WESTERN CONUS THIS WEEKEND WITH A DEEP TROUGH ACROSS THE EASTERN
CONUS. THIS WILL ALLOW A LATE-SEASON COLD FRONT TO DIVE SOUTH AND
BEGIN TO ENTER OUR NORTHERN CWA SATURDAY NIGHT. POPS FOR NOW WILL
BE IN THE 20 TO 50 PERCENT RANGE BUT COULD BE RAISED AS
CONFIDENCE INCREASES CLOSER TO THIS WEEKEND. PRECIPITABLE WATER
VALUES WILL BE NEAR 2 INCHES AND THIS COMBINED WITH A FRONTAL
BOUNDARY AND EXPECTED SLOW STORM MOTIONS COULD LEAD TO LOCALLY
HEAVY RAINFALL. THIS WILL BE SOMETHING THAT NEEDS TO BE WATCHED
CLOSELY AS WE NEAR THE WEEKEND. THE FRONT IS EXPECTED TO LIFT
NORTH ON MONDAY AND ADDITIONAL RAIN CHANCES WILL CONTINUE THROUGH
TUESDAY WITH PLENTY OF MOISTURE LEFT OVER.
&&
.PRELIMINARY POINT TEMPS/POPS...
AUSTIN CAMP MABRY 90 72 89 73 91 / 20 10 20 10 -
AUSTIN BERGSTROM INTL AIRPORT 89 71 88 72 90 / 20 10 20 10 -
NEW BRAUNFELS MUNI AIRPORT 89 72 89 73 91 / 20 10 20 10 -
BURNET MUNI AIRPORT 88 71 89 72 91 / 10 10 10 10 -
DEL RIO INTL AIRPORT 89 73 91 73 93 / 20 10 10 10 -
GEORGETOWN MUNI AIRPORT 89 72 89 73 91 / 10 10 10 10 -
HONDO MUNI AIRPORT 88 72 89 72 90 / 20 10 20 10 -
SAN MARCOS MUNI AIRPORT 88 72 88 73 90 / 20 10 20 10 -
LA GRANGE - FAYETTE REGIONAL 90 73 89 74 90 / 30 10 40 10 10
SAN ANTONIO INTL AIRPORT 88 73 89 74 90 / 20 10 20 10 -
STINSON MUNI AIRPORT 89 73 89 73 91 / 20 10 20 10 -
&&
.EWX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
MESOSCALE/AVIATION...24
SYNOPTIC/GRIDS...TREADWAY
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
346 AM CDT WED JUN 24 2015
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 346 AM CDT WED JUN 24 2015
LATEST WATER VAPOR SATELLITE IMAGERY INDICATING WEST TO EAST ZONAL
FLOW ACROSS THE NORTHERN TIER STATES WITH SEVERAL PIECES OF
ENERGY EMBEDDED IN THE FLOW. LATEST 08Z SURFACE ANALYSIS SHOWS
SURFACE FRONT EXTENDING FROM WESTERN KANSAS INTO WESTERN KENTUCKY.
CURRENT MOSAIC RADAR INDICATES SHOWERS AND THUNDERSTORMS OVER
EASTERN NEBRASKA...CENTRAL AND WESTERN IOWA. THIS IS IN RESPONSE
TO 850-700MB MOISTURE TRANSPORT/CONVERGENCE IN ASSOCIATION WITH A
SUBTLE SHORTWAVE TROUGH OVER CENTRAL NEBRASKA.
MAIN FORECAST CONCERNS TODAY INTO TONIGHT CONTINUE TO BE PLACEMENT
OF SURFACE FRONT AND HOW FAR NORTH SURFACE FRONT MOVES TODAY.
FIRST WEAK SHORTWAVE OVER EASTERN NEBRASKA/WESTERN IOWA AND
ASSOCIATED CONVECTION IS EXPECTED TO REMAIN TO THE SOUTH OF THE
FORECAST AREA THIS MORNING. A SECOND PIECE OF ENERGY OVER WESTERN
SOUTH DAKOTA WILL QUICKLY PUSH INTO CENTRAL IOWA AROUND 18Z TODAY
AND SPREAD SCATTERED CONVECTION INTO THE FAR SOUTHERN PART OF THE
FORECAST AREA.
THEN FOCUS TURNS TO SURFACE FRONT...AS THE LATEST 24.00Z GFS/NAM
CONTINUE TO LIFT SURFACE FRONT INTO CENTRAL IOWA...AND THE 24.00Z
ECMWF SUGGEST FRONT WILL REMAIN OVER IOWA/MISSOURI BORDER THIS
AFTERNOON INTO TONIGHT. HIGH RESOLUTION MODELS...ARW/NMM/NAM
NEST...SHOW SETTLE DIFFERENCES ON PLACEMENT OF SURFACE FRONT OVER
SOUTHERN IOWA. WITH THE 24.00Z GFS/NAM FARTHER NORTH SOLUTION...CONVECTION
DEVELOPS OVER THE SOUTHERN HALF OF THE FORECAST AREA. WITH THE
FARTHER SOLUTION PLACEMENT OF THE FRONT...THE 24.00Z ECMWF AND
HIGH RESOLUTION MODELS FOCUS CONVECTION OVER THE FAR SOUTHERN
FORECAST AREA OR JUST TO THE SOUTH OF THE FORECAST AREA THIS
AFTERNOON INTO TONIGHT. WITH THIS...CONFIDENCE TODAY INTO TONIGHT
REMAINS ON THE LOW SIDE. GIVEN THE HIGH RESOLUTION MODELS ARE
SOMEWHAT IN AGREEMENT WITH THE 24.00Z ECMWF...WILL CONTINUE TO
FOCUS HIGHER PRECIPITATION CHANCES OVER THE SOUTHERN PART OF THE
FORECAST AREA TODAY INTO TONIGHT.
MODELS CONTINUE TO SHOW DECENT SHEAR OF 30 TO 40 KNOTS OF 0-3KM
SHEAR/AROUND 50 KNOTS OF 0-6KM SHEAR ACROSS MUCH OF THE FORECAST
AREA...AND 0-6KM MOST UNSTABLE CAPE OF 1000-2000 J/KG ACROSS THE
EXTREME SOUTHERN PORTION OF THE FORECAST AREA. CANNOT RULE THE
POSSIBILITY OF AN ISOLATED LARGE HAIL OR DAMAGING WIND WITH ANY
THUNDERSTORMS CONFINED TO THE FAR SOUTHERN PART OF THE FORECAST
AREA. THE BIGGEST CONCERN IS THE POSSIBILITY OF ENTRAINMENT OF
CONVECTION ACROSS THE FAR SOUTHERN PART OF THE FORECAST AREA LATE
THIS EVENING INTO TONIGHT...WHICH WOULD POSE A FLASH FLOODING
THREAT. THE MAJORITY OF THE HIGH RESOLUTION MODELS SUGGEST
ENTRAINMENT OF THE CONVECTION TO BE JUST SOUTH OF THE FORECAST
AREA. IF CONVECTION DEVELOPS FARTHER NORTH...THEN THE FAR SOUTHERN
FORECAST AREA...COULD SEE THE POTENTIAL FOR LOCALLY HEAVY
RAINFALL.
.LONG TERM...(THURSDAY THROUGH TUESDAY)
ISSUED AT 346 AM CDT WED JUN 24 2015
MAIN SHORTWAVE TROUGH PUSHES EAST OF THE FORECAST AREA AND WEAK
SUBSIDENCE BEHIND SHORTWAVE TROUGH WILL ALLOW FOR PRECIPITATION TO
MOVE EAST OF THE FORECAST AREA THURSDAY INTO THURSDAY NIGHT. THE
24.00Z GFS/NAM/ECMWF ARE IN AGREEMENT IN DIGGING UPPER LEVEL
TROUGH INTO THE OHIO RIVER VALLEY FRIDAY. WITH DEEPER
MOISTURE/CONVERGENCE WEST/SOUTH OF THE FORECAST AREA...AND A DRY
EASTERLY FLOW ALOFT OVER FORECAST AREA. HAVE REDUCED PRECIPITATION
CHANCES OVER THE EASTERN FORECAST AREA AND KEPT PRECIPITATION
CHANCES CONFINED OVER THE WESTERN FORECAST AREA.
THE LATEST 24.00Z GFS/ECMWF/GEM CONTINUE TO DIG UPPER LEVEL TROUGH
OVER THE OHIO RIVER VALLEY SATURDAY INTO EARLY NEXT WEEK. TIMING
DIFFERENCES ON EACH INDIVIDUAL IMPULSE EMBEDDED IN THE NORTHWEST
FLOW ALOFT ARE INDICATED BETWEEN THE MODELS THROUGH THIS PERIOD.
WILL CONTINUE WITH TREND OF PERIODIC SMALL CHANCES OF PRECIPITATION
SATURDAY THROUGH TUESDAY. TEMPERATURES THROUGH THE PERIOD ARE
EXPECTED TO BE SLIGHTLY BELOW NORMAL OR NEAR NORMAL...AS NORTHERLY
FLOW ALOFT ADVECTS COOLER AIRMASS INTO THE FORECAST AREA.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z WEDNESDAY NIGHT)
ISSUED AT 1141 PM CDT TUE JUN 23 2015
THE FRONT REMAINS OVER CENTRAL KANSAS INTO CENTRAL MISSOURI LATE
THIS EVENING. CONVECTION HAS FORMED NEAR AN AREA OF LOW PRESSURE
OVER EASTERN COLORADO AND WAS MOVING EAST ALONG AND NORTH OF THE
FRONT. NO MODEL IS PICKING UP ON THIS CONVECTION WITH THE 24.00Z
NAM AND 24.03Z HRRR COMPLETELY WHIFFING ON THIS. THE 24.00Z SPC
WRF AT LEAST SHOWED THIS BUT THEN DIES IT OUT IN FAVOR OF
DEVELOPING CONVECTION OVER EASTERN NEBRASKA AND SOUTHERN
IOWA...WHICH IS WHERE THE NAM AND HRRR ALSO TRY TO INITIATE
OVERNIGHT. WITH BOTH SCENARIOS...THE CONVECTION WILL STAY TO THE
SOUTH TONIGHT BUT IT WILL IMPACT HOW FAR NORTH THE FRONT CAN
PROGRESS WEDNESDAY. THE NAM WITH THE 00Z RUN IS EVEN FARTHER NORTH
WITH DEVELOPMENT LATE WEDNESDAY AFTERNOON AND EVENING THAN WHAT
THE 18Z RUN WAS. THE SPC WRF SUGGESTS THE FRONT STAYS WELL TO THE
SOUTH WITH DEVELOPMENT OCCURRING ACROSS SOUTHERN NEBRASKA AND IOWA
INTO NORTHERN MISSOURI. THE 24.00Z GFS LOOKS TO BE IN BETWEEN
THESE OTHER TWO SOLUTIONS WITH MOST OF THE ACTIVITY OVER THE
NORTHERN HALF OF IOWA. WITH TWO OUT THREE OF THE NEW MODEL RUNS
KEEPING THE CONVECTION SOUTH OF THE AREA WEDNESDAY...PLAN TO TO DO
THE SAME WITH THE UPCOMING TAFS.
&&
.HYDROLOGY...
ISSUED AT 346 AM CDT WED JUN 24 2015
THE RECENT RAINFALL THAT OCCURRED MONDAY MORNING NEAR THE
MINNESOTA/IOWA BORDER HAS CAUSED HIGH RIVER LEVELS ON AREA RIVERS
AND STREAMS. MANY OF THE RIVERS HAVE BEGUN TO RECEDE...HOWEVER SOME
FLOODING REMAINS ALONG THE CEDAR RIVER. REFER TO THE LATEST FLOOD
STATEMENTS FOR THE LATEST STAGES AND FORECAST.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...DTJ
LONG TERM...DTJ
AVIATION...04
HYDROLOGY...DTJ
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
1141 PM CDT TUE JUN 23 2015
.SHORT TERM...(THIS EVENING THROUGH WEDNESDAY)
ISSUED AT 341 PM CDT TUE JUN 23 2015
CURRENTLY AS OF 20Z...WATER VAPOR LOOP AND RAP 500MB HEIGHT ANALYSIS
SHOWED SUBTROPICAL RIDGING ENCOMPASSING THE SOUTHERN U.S.. WHILE A
WEST-NORTHWEST FLOW RUNS FROM THE PACIFIC NORTHWEST INTO THE MID-
ATLANTIC. THE TWO MAIN SHORTWAVES OF NOTE WERE OVER THE SIOUX FALLS
AREA AND SOUTHERN BRITISH COLUMBIA. THE ONE IN SIOUX FALLS ALONG
WITH A WIDE AREA OF LOW TO MID LEVEL FRONTOGENESIS WAS HELPING TO
PRODUCE PLENTY OF ALTOSTRATUS FROM SOUTH DAKOTA/NEBRASKA EAST INTO
THE SOUTHERN PORTION OF THE FORECAST AREA. AIRMASS HAS BEEN TOO DRY
TO SUPPORT ANY PRECIPITATION DESPITE SEEING ECHOES ON RADAR...AS
REFLECTED BY THE 12Z MPX SOUNDING WITH A 700MB DEWPOINT DEPRESSION
OF 40C. ONLY A VERY FEW SITES HAVE REPORTED SPRINKLES. MAIN SURFACE
FRONTAL BOUNDARY ASSOCIATED WITH THE FRONTOGENESIS WAS WELL TO THE
SOUTH...SITUATED JUST SOUTH OF I-70 AND WAS VERY SLOWLY LIFTING
NORTH TODAY. THAT NORTHWARD PROGRESS HAS BEEN HELD BACK BY A
PERSISTENT COMPLEX OF CONVECTION FROM SOUTHEAST NEBRASKA INTO THE
KANSAS CITY AREA. SUNSHINE TODAY COMBINED WITH 850MB TEMPS AROUND
10C HAS RESULTED IN HIGHS MOSTLY IN THE 70S. MUCH LOWER DEWPOINTS
TODAY THAN YESTERDAY WITH MIXING AND DRY AIR RESULTING IN READINGS
OF 45 TO 55F.
LOOK FOR A CONTINUATION OF QUIET CONDITIONS TONIGHT ACROSS THE
FORECAST AREA AS THE AREA OF HIGH PRESSURE HELPING TO PROVIDE THE
DRY CONDITIONS ONLY DRIFTS OFF TO THE SOUTHEAST. WE WILL HAVE TO
DEAL WITH THE SOME HIGHER BASED FRONTOGENESIS...YIELDING SOME
ALTOSTRATUS AS WE ARE SEEING TODAY. THESE CLOUDS SHOULD HELP TO
PRECLUDE FOG FORMATION...AND ALSO KEEP TEMPERATURES FROM FALLING
BELOW THE MID 50S.
THE MORE INTERESTING PART OF THE SHORT TERM IS FOR WEDNESDAY. MODELS
CONTINUE TO ADVERTISE THAT THE FRONTAL BOUNDARY IN KANSAS WILL LIFT
NORTHWARD OVER THE NEXT 24 HOURS...IN RESPONSE TO A MONSOONAL
SHORTWAVE COMING OUT OF COLORADO AND ROTATING AROUND THE SOUTHERN
U.S. SUBTROPICAL RIDGE. AS THIS OCCURS WITH THE NOCTURNAL LOW LEVEL
JET...MODELS ARE ADVERTISING AT LEAST CONVECTION IF NOT AN MCS TO
DEVELOP OVER EASTERN NEBRASKA AND WESTERN IOWA LATE TONIGHT. CORFIDI
VECTORS WOULD TAKE THIS MCS INTO NORTHERN MO WEDNESDAY MORNING...
HOLDING THE FRONT BACK. HOWEVER...SOME GUIDANCE LIKE THE 23.12Z
GFS/NAM WANT TO KEEP MOVING THE FRONT NORTH INTO THE AFTERNOON...
SPREADING EITHER PREVIOUS OR NEW CONVECTION INTO NORTHEAST IA AND
SOUTHWEST WI. BELIEVE THIS IS GOING TO BE TOUGH AS CLOUD DEBRIS
LIMITS DAYTIME MIXING...AND CONVECTIVE OUTFLOW HOLDS THE BOUNDARY
BACK. MORE LIKELY...WHEN NEW CONVECTION FIRES IT WILL BE FARTHER
SOUTH CLOSER TO THE FRONT...WHICH SHOULD BE HUNG UP NEAR THE MO/IA
BORDER BY 00Z THU. THE 23.12Z ECMWF REMAINS THE FARTHEST SOUTH MODEL
WITH THE FRONT AND CONVECTION...AND SEEMS MOST REASONABLE GIVEN
EXPECTED CONVECTION TRACKS. THEREFORE...PRECIPITATION CHANCES ARE
HIGHEST IN NORTHEAST IA BUT STILL ONLY AS MUCH AS 50 PERCENT BY LATE
IN THE DAY GIVEN ANTICIPATION FOR MOST CONVECTION TO STAY SOUTH.
GIVEN THE MAJORITY OF CAPE TO STAY WELL SOUTH OF THE AREA...THE
SLIGHT RISK ON SPCS DAY 2 OUTLOOK WAS SHIFTED MOSTLY OUT OF THE
FORECAST AREA. ITS WORTH NOTING THAT MODELS...OUTSIDE THE 23.12Z
ECMWF...HAVE REALLY STRUGGLED WITH THE ONGOING CONVECTION NORTH OF
THE FRONT IN THE KANSAS CITY AREA.
THERE IS ALSO SOME CONCERN FOR SHOWERS AND STORMS TO FIRE NORTH OF
HIGHWAY 29 WEDNESDAY AFTERNOON...RELATED TO THE SHORTWAVE IN BRITISH
COLUMBIA HEADING INTO NORTHERN PORTIONS OF MN OR WI. THE ECMWF IS
SLOWEST WITH THE SHORTWAVE AND THEREFORE IS DRY...WHEREAS THE GFS
AND NAM ARE FASTER AND HAVE PRECIP. THE GFS/NAM ALSO HAVE HIGHER
SURFACE DEWPOINTS WHICH SEEM TOO HIGH. THEREFORE...HAVE ONLY KEPT A
20 PERCENT CHANCE IN TAYLOR COUNTY LATE IN THE DAY.
WITH 850MB TEMPS IN THE 12-14C RANGE AND SOME SUN LIKELY FOR AT
LEAST THE MORNING HOURS...HIGHS SHOULD PUSH INTO THE MID 70S TO LOW
80S...WARMEST TO THE NORTH WHERE LONGER PERIOD OF SUN IS EXPECTED.
.LONG TERM...(WEDNESDAY NIGHT THROUGH TUESDAY)
ISSUED AT 341 PM CDT TUE JUN 23 2015
23.12Z ECMWF/GFS/CANADIAN MAINTAIN THE SAME LONG WAVE PATTERN THEY
HAVE BEEN SHOWING THE PAST SEVERAL DAYS...WITH STRONG SUBTROPICAL
RIDGING SHIFTING AND BUILDING OVER THE WESTERN U.S. ON
THURSDAY...CAUSING FAIRLY DEEP TROUGHING FOR THIS TIME OF YEAR OVER
THE EASTERN U.S.. THIS SHIFT IS IN RESPONSE TO THE MADDEN JULIAN
OSCILLATION GOING INTO AN ANOMALOUSLY STRONG PHASE 6. WHAT THIS
MEANS FOR THE FORECAST AREA IS TEMPERATURES TO HOLD AT OR NEAR
SEASONABLE NORMALS...WITH PERHAPS A SLOW WARMUP LATE IN THE WEEKEND
INTO EARLY NEXT WEEK. ANY GULF OF MEXICO RETURN OF MOISTURE SHOULD
GET SHUTOFF WITH MOISTURE SOURCES MOSTLY TURNING TO
EVAPOTRANSPIRATION AND WHAT SYSTEMS CAN BRING OFF THE PACIFIC DOWN
THE RIDGE.
THE MAIN FOCUS FOR PRECIPITATION REMAINS WEDNESDAY NIGHT.
HOWEVER...SIMILAR TO WEDNESDAY...HOW FAR NORTH THE WARM FRONT NEAR
THE IA/MO BORDER AT 00Z THU REALLY DETERMINES THE CONVECTION
CHANCES. CURRENT THINKING LIES ALONG THE MORE PREFERRED ECMWF VERSUS
THE BIASED NORTH GFS/NAM/SREF/CANADIAN...WHICH SUGGESTS ANOTHER MCS
FORMING OVER CENTRAL IOWA WEDNESDAY EVENING...MARCHING LIKELY
SOUTHEASTWARD FOLLOWING CORFIDI VECTORS. THIS IS IN LINE WITH THE
HIGHEST SPC DAY 2 OUTLOOK PROBABILITIES. THE NORTHERN PART OF THIS
MCS COULD CLIP OUR FAR SOUTH...THUS HAVE THE HIGHEST 50-60 PERCENT
CHANCES THERE FOR THE EVENING. TRIMMED CHANCES BACK FARTHER NORTH
AND AREAS NORTH OF U.S. HIGHWAY 18 MAY END UP DRY. THE LONE
EXCEPTION WOULD BE NORTH OF HIGHWAY 29...CLOSER TO THAT SHORTWAVE
TROUGH MARCHING ACROSS MN AND NORTHERN WI. PRECIPITATION SHOULD
DIMINISH WEST TO EAST DURING THE OVERNIGHT HOURS AS THE MCS AND
SHORTWAVE TROUGHS MOVE FURTHER AWAY FROM THE AREA.
FOR THURSDAY AND FRIDAY...THE 23.12Z GFS AND TO A LESSER EXTENT THE
NAM WANT TO FIRE UP SOME DIURNAL SHOWERS AND STORMS...ASSOCIATED
WITH WEAK SHORTWAVES DROPPING THROUGH THE NORTHWEST FLOW. THE 23.12Z
ECMWF SHOWS THESE SAME SHORTWAVES BUT IS DRY. MUCH OF THE DIFFERENCE
RELATES TO BOUNDARY LAYER MOISTURE AND ITS IMPACT TO CAPE. AT BOTH
00Z FRI AND 00Z SAT...THE GFS IS NEARLY 10F HIGHER ON SURFACE
DEWPOINTS TO THE ECMWF. THINKING THE ECMWF IS MORE CORRECT AND THUS
HAVE ONLY 20-30 PERCENT CHANCES AT MOST...HIGHEST IN WESTERN AREAS.
SATURDAY LOOKS DRY WITH HIGH PRESSURE IN PLACE...BUT THEN THERE IS
AN ISSUE WITH SUNDAY INTO MONDAY WITH MODELS TIMING A STRONGER
SHORTWAVE TROUGH DROPPING THROUGH THE NORTHWEST FLOW. THE 23.12Z
ECMWF IS FASTEST AND SPREADS SOME CONVECTION ACROSS THE AREA ON
SUNDAY...WHEREAS THE 23.12Z CANADIAN/GFS WAIT UNTIL EITHER LATER
SUNDAY NIGHT OR MONDAY. GIVEN THE SPREAD...HAVE KEPT A 20-40 PERCENT
CHANCE FOR ALL 3 12 HOUR TIME PERIOD. NEEDLESS TO SAY A GOOD PORTION
CAN PROBABLY BE DRIED OUT IN LATER FORECASTS ONCE THE TIMING GETS
RESOLVED. ANOTHER NORTHWEST FLOW WAVE IS PROGGED FOR TUESDAY...
RESULTING IN MORE CHANCES OF PRECIPITATION.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z WEDNESDAY NIGHT)
ISSUED AT 1141 PM CDT TUE JUN 23 2015
THE FRONT REMAINS OVER CENTRAL KANSAS INTO CENTRAL MISSOURI LATE
THIS EVENING. CONVECTION HAS FORMED NEAR AN AREA OF LOW PRESSURE
OVER EASTERN COLORADO AND WAS MOVING EAST ALONG AND NORTH OF THE
FRONT. NO MODEL IS PICKING UP ON THIS CONVECTION WITH THE 24.00Z
NAM AND 24.03Z HRRR COMPLETELY WHIFFING ON THIS. THE 24.00Z SPC
WRF AT LEAST SHOWED THIS BUT THEN DIES IT OUT IN FAVOR OF
DEVELOPING CONVECTION OVER EASTERN NEBRASKA AND SOUTHERN
IOWA...WHICH IS WHERE THE NAM AND HRRR ALSO TRY TO INITIATE
OVERNIGHT. WITH BOTH SCENARIOS...THE CONVECTION WILL STAY TO THE
SOUTH TONIGHT BUT IT WILL IMPACT HOW FAR NORTH THE FRONT CAN
PROGRESS WEDNESDAY. THE NAM WITH THE 00Z RUN IS EVEN FARTHER NORTH
WITH DEVELOPMENT LATE WEDNESDAY AFTERNOON AND EVENING THAN WHAT
THE 18Z RUN WAS. THE SPC WRF SUGGESTS THE FRONT STAYS WELL TO THE
SOUTH WITH DEVELOPMENT OCCURRING ACROSS SOUTHERN NEBRASKA AND IOWA
INTO NORTHERN MISSOURI. THE 24.00Z GFS LOOKS TO BE IN BETWEEN
THESE OTHER TWO SOLUTIONS WITH MOST OF THE ACTIVITY OVER THE
NORTHERN HALF OF IOWA. WITH TWO OUT THREE OF THE NEW MODEL RUNS
KEEPING THE CONVECTION SOUTH OF THE AREA WEDNESDAY...PLAN TO TO DO
THE SAME WITH THE UPCOMING TAFS.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...AJ
LONG TERM...AJ
AVIATION...04
AREA FORECAST DISCUSSION
NWS JACKSONVILLE FL
921 AM EDT WED JUN 24 2015
...A FEW STRONG TO SEVERE STORMS POSSIBLE THIS AFTERNOON...
.UPDATE...SFC RIDGE CONTS WELL S OF THE AREA WITH PREVAILING SW
TO W FLOW OVER THE LOCAL REGION. WATER VAPOR AND IR IMAGERY SHOWS
A SLOWLY WEAKENING MCS OVER SRN AL WITH SOME DEBRIS MID LEVEL
CLOUDS OVER PORTIONS OF NE FL AND SE GA. THESE CLOUDS MAY SLOW
HEATING SOMEWHAT BUT SHOULD STILL BE ABLE TO REACH THE LOWER TO
MID 90S TODAY. A MID LEVEL TROUGH ACROSS EXTREME SE GA AND NE FL
WILL SLOWLY SINK SWD AND COMBINE WITH HIGH MOISTURE (PWATS NEAR 2
INCHES) AND SEA BREEZES TO PRODUCE SCT TO NUMEROUS SHOWERS AND
STORMS LATER TODAY. SHORT RANGE GUIDANCE AND VSBY IMAGERY SUGGESTS
LIKELY INITIATION OF CONVECTION FROM THE W COAST SEA BREEZE
BOUNDARY...WHICH WILL MOVE INTO THE I-75 CORRIDOR BY EARLY AFTN.
BEST COVERAGE CONTINUES TO POINT TOWARD NE FL DUE TO BETTER
MOISTURE AND DYNAMICS. A MODIFIED RAP SOUNDING SHOWS SBCAPE OF
ABOUT 2600 J/KG AND LI OF -6 AND DCAPE SUPPORTIVE OF STRONG TO
POSSIBLY SEVERE WET DOWNBURSTS OF 50-60 MPH. WEAK STORM MOTION AND
HIGH CAPE VALUES WILL LEAD TO TORRENTIAL DOWNPOURS WITH LOCAL
FLOODING ISSUES POSSIBLE. SCT EVENING CONVECTION WILL SLOWLY
DISSIPATE LATE TONIGHT.
&&
.AVIATION...VFR PREVAILS THROUGH EARLY AFTN WITH A GOOD CHANCE OF
TSTMS AT GNV BY MID AFTN THEN REST OF TAFS BY MID TO LATE AFTN.
VCTS FOR MOST TAFS LOOKS GOOD AT THIS POINT WITH TEMPO GROUP FOR
GNV 17Z-20Z. MVFR VSBY/CIG WITH STRONG WIND GUSTS LIKELY IN
STRONGER STORMS THIS AFTERNOON.
&&
.MARINE...CURRENT FCST ON TRACK WITH OFFSHORE FLOW TURNING MORE S
AND SE BY LATE AFTN FROM E COAST SEA BREEZE. SEAS OF 3 FT OR LESS
WITH SHOWERS AND STORMS POSSIBLE THIS AFTN. WINDS INCREASE AGAIN
TONIGHT TO NEAR SCEC CONDS OFFSHORE. MAIN CONCERNS CENTERED AROUND
TSTMS ACTIVITY LATER THIS AFTN OVER THE NEARSHORE WATERS. WILL
ADJUST WX FCST A BIT TODAY AND TONIGHT FOR THE MORNING UPDATE.
RIP CURRENTS: LOW RISK THROUGH THU OWING TO LIGHT SWELLS AND
PREVAILING OFFSHORE FLOW.
&&
.PRELIMINARY POINT TEMPS/POPS...
AMG 96 74 95 74 / 20 20 40 40
SSI 90 77 89 78 / 30 30 40 30
JAX 93 75 90 74 / 50 40 50 40
SGJ 90 75 89 75 / 60 50 50 40
GNV 92 73 89 72 / 60 50 50 40
OCF 91 75 89 73 / 50 50 50 40
&&
.JAX WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
GA...NONE.
AM...NONE.
&&
$$
SHASHY/ALLEN
AREA FORECAST DISCUSSION
NWS CHARLESTON SC
1139 AM EDT WED JUN 24 2015
.SYNOPSIS...
ATLANTIC HIGH PRESSURE WILL PREVAIL MUCH OF THIS WEEK WHILE A TROUGH
OF LOW PRESSURE PERSISTS INLAND. A COLD FRONT WILL STALL TO THE NORTH
LATE WEEK INTO THE WEEKEND BEFORE FINALLY CROSSING THE AREA LATE
SUNDAY. THE FRONT MAY STALL JUST OFFSHORE BEFORE DISSIPATING EARLY
NEXT WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
FOR THE MIDDAY UPDATE WE HAVE MADE MINOR CHANGES TO HOURLY
TEMPS...POPS AND SKY COVER...BUT NOTHING MAJOR. SATELLITE IMAGES
AND SURFACE ANALYSIS SHOWING AN OUTFLOW BOUNDARY FROM THE PREVIOUS
MCS MOVING SOUTHWARD FROM FAR SE NC THROUGH THE PEE-DEE AND
UPSTATE OF SC INTO NORTHERN GA. THIS IS WHERE CONVECTION WILL
LIKELY START POPPING FIRST.
AFTER OUR BRIEF RESPITE FROM THE EXTREME HEAT AND HUMIDITY
COMBINATION YESTERDAY...IT/S BACK TO THE OPPRESSIVE AND STICKY
CONDITIONS THAT WE HAVE SEEN MUCH OF THE PAST 2 WEEKS. TEMPS ARE
RUNNING ON AVERAGE ABOUT 2-3F WARMER THAN 24 HOURS AGO...AND WITH
850 MB TEMPS OF 19-20C AND PLENTY OF INSOLATION...WE/RE ON OUR WAY
TO THE MID AND UPPER 90S INLAND FROM US-17. A FEW SPOTS MIGHT EVEN
PEAK AT THE CENTURY MARK. DEW POINTS WILL MIX OUT A BIT
INLAND...BUT WILL POOL BEHIND THE SEA BREEZE...WHICH SUPPORTS MOST
HEAT INDICES AS HIGH AS 105-109F...BUT A FEW SPOTS OF THE COASTAL
CORRIDOR WILL MAX OUT AT 110-112F AROUND THE TIME OF THE SEA
BREEZE PASSAGE. OUR HEAT ADVISORY WILL OBVIOUSLY REMAIN ACTIVE.
THE FORECAST FOR HOW CONVECTION WILL PAN OUT IS FAR FROM CERTAIN
GIVEN A WIDE DISPARITY IN VARIOUS MODELS. WE STILL HAVE A SUBTLE
WEAKNESS IN THE RIDGING ALOFT...BUT THAT LOOKS TO BE JUST OFF THE
COAST. THERE WILL BE VARIOUS MESO-SCALE BOUNDARIES SUCH S OUTFLOW
FROM EARLIER MCS THAT MOVED OFF THE MID-ATLANTIC AND ANOTHER FROM
ALABAMA. THERE IS ALSO THE EVER PRESENT PIEDMONT TROUGH AND THE
SEA BREEZE BOUNDARY. THESE FACTORS SHOULD PROVIDE THE NECESSARY
INITIATION...BUT THERE IS STILL A STRONG 3-5C CAP AND UNFAVORABLE
MID LEVEL LAPSE RATES WITH WARM 500 MB TEMPS...IMPLYING THAT
STORMS MAY HAVE A DIFFICULT TIME IN ATTAINING MUCH VERTICAL
GROWTH. ON THE FAVORABLE SIDE OUR LOW LEVEL LAPSE RATES ARE
FAVORABLE AND THERE IS PLENTY OF INSTABILITY WITH SBCAPES FORECAST
TO REACH 4000-4500 J/KG AND LIFTED INDEX OF -6 TO -8C. LOOK FOR
CONVECTION TO GET GOING AROUND 1-2 PM AS WE HIT OUR CONVECTIVE
TEMP IN THE MID 90S.
FOR THE MOMENT A PULSE TYPE ENVIRONMENT SEEMS A MORE LIKELY
CONVECTIVE MODE RATHER THAN MULTI-CELLULAR...BUT IF BOUNDARY
INTERACTIONS AND MERGERS TAKE PLACE THAT COULD CHANGE. WE/LL
MAINTAIN A PROBABILITY FORECAST OF 20-30 PERCENT...HIGHEST INLAND
AND MAINTAIN A CLOSE WATCH ON MESO-SCALE TRENDS TO SEE IF WE NEED
TO RAISE POPS.
DCAPES OF 1000-1200 J/KG AND WINDEX VALUES OF 65 KT WOULD SUPPORT
STRONG DOWNBURST WINDS...AIDED BY PRECIP LOADING WITH PWATS CLOSE
TO THE 90TH PERCENTILE FOR LATE JUNE. OTHER HAZARDS INCLUDE
FREQUENT LIGHTNING STRIKES...VERY HEAVY RAINS DUE TO A STORM
MOTION OF ONLY AROUND 5 MPH AND SHOULD ANY TALL STORMS DEVELOP
THERE IS ALSO HAIL RISK. PROBABILITY OF SEVERE WEATHER IS STILL
TOO LOW TO INCLUDE IN THE HAZARDOUS WEATHER OUTLOOK...MOST NOTABLY
DUE TO THE HRRR SHOWING LITTLE IN THE WAY OF CONVECTIVE
ORGANIZATION.
CONDITIONS SHOULD BE MAINLY QUIET TONIGHT WITH PARTLY CLOUDY SKIES
AND LOWS A BIT WARMER THAN WEDNESDAY MORNING...ESPECIALLY IF TSTMS
COVERAGE IS LOWER END TODAY.
&&
.SHORT TERM /THURSDAY THROUGH SATURDAY/...
THURSDAY...PERSISTENT MID LEVEL RIDGE WILL HOLD FAIRLY STRONG FOR
ONE MORE DAY...ALTHOUGH SUBTLE WEAKENING WILL BEGIN TO OCCUR. THE
SURFACE PATTERN WILL CONTINUE TO BE FAIRLY STATIC AS THE AREA
REMAINS ON THE WESTERN PERIPHERY OF ATLANTIC HIGH PRESSURE WITH A
PIEDMONT TROUGH SITUATED INLAND. HIGH TEMPERATURES IN THE MID/UPPER
90S AWAY FROM THE COAST WILL COMBINE WITH MODERATE HUMIDITY LEVELS
TO PRODUCE HEAT INDICES OF 105-108 IN THE AFTERNOON. THUS A HEAT
ADVISORY WILL LIKELY BE NEEDED. LARGE SCALE FORCING WILL LARGELY BE
MISSING HOWEVER CONVECTION WILL DEVELOP AS A RESULT OF SEA BREEZE
AND/OR CONVERGENCE ALONG SURFACE TROUGH. FORECAST SURFACE BASED
CAPE NEAR 3000 J/KG MAY SUPPORT A FEW STRONGER POSSIBLY SEVERE
STORMS...WITH GUSTY WINDS THE PRIMARY THREAT GIVEN DCAPE VALUES IN
EXCESS OF 1000 J/KG. THURSDAY NIGHT...SURFACE LOW PRESSURE WILL
CROSS THE MID-ATLANTIC STATES ABSORBING THE PIEDMONT TROUGH. AN
ATTENDANT FRONT WILL STALL NORTH OF THE AREA. LOWS WILL BE QUITE
MILD RANGING FROM THE MID 70S INLAND TO AROUND 80 ALONG THE COAST.
FRIDAY...AN AREA OF LOW PRESSURE WILL DEVELOP OVER THE CAROLINAS
ALONG THE AFOREMENTIONED STALLED FRONT. DEEP MOISTURE AND PROXIMITY
TO BOUNDARY WILL ALLOW FOR HIGHER COVERAGE OF SHOWERS AND
THUNDERSTORMS. FORECAST CURRENTLY FEATURES HIGH CHANCE POPS OVER
MUCH OF THE AREA DURING PEAK HEATING HOURS. A FEW STRONGER STORMS
WILL BE POSSIBLE ESPECIALLY IN THE NORTHERN ZONES WHERE INSTABILITY
AND MID LEVEL ENVIRONMENT IS MORE FAVORABLE...WITH GUSTY WINDS
PRIMARY THREAT. FORECAST HEAT INDICES MAY BRIEFLY REACH THE LOCAL
HEAT ADVISORY CRITERIA OF 105 IN THE AFTERNOON WITH HIGH
TEMPERATURES IN THE LOW/MID 90S...HOWEVER DURATION AND AREAL EXTENT
WILL BE MARGINAL AT BEST AND GIVEN EXPECTED CONVECTION...THINK A
HEAT ADVISORY WILL LIKELY NOT BE NEEDED. CONVECTION MAY LINGER INTO
THE OVERNIGHT PERIOD...WITH FOCUS SHIFTING MORE TO THE COASTAL
WATERS. LOWS WILL AGAIN BE IN THE MID TO UPPER 70S.
SATURDAY...THE UPPER LEVEL PATTERN WILL BECOME MUCH MORE AMPLIFIED
AS DEEPENING TROUGH AND ASSOCIATED VORT MAX DIGS INTO THE GREAT
LAKES REGION. THIS WILL HELP SEND ANOTHER AREA OF LOW PRESSURE
TOWARDS EAST COAST WHICH WILL EVENTUALLY ENGULF THE STATIONARY
FRONT/LOW. BETTER UPPER SUPPORT...DEEP MOISTURE AND VARIOUS SURFACE
BOUNDARIES WILL ALLOW FOR A FAIRLY ACTIVE DAY WITH STRONGER STORMS
POSSIBLE GIVEN DECENT SHEAR AND FORECAST INSTABILITY. HIGH
TEMPERATURES WILL MAINLY BE IN THE LOW 90S.
&&
.LONG TERM /SATURDAY NIGHT THROUGH TUESDAY/...
BROAD UPPER TROUGH WILL ENCOMPASS THE EASTERN U.S. THROUGH THE LONG
TERM PERIOD. A POTENT SHORTWAVE WILL SEND AN AREA OF LOW PRESSURE
AND ATTENDANT FRONT THROUGH THE FORECAST AREA ON SUNDAY. GIVEN
FORCING FROM UPPER JET...SHORTWAVE ENERGY AND COLD FRONT...IT SHOULD
BE A PRETTY ACTIVE DAY ESPECIALLY GIVEN DECENT SHEAR AND DEEP
MOISTURE. THE FRONT WILL LIKELY PUSH OFF THE COAST EARLY
MONDAY...AND REMAIN STATIONARY OFFSHORE BEFORE DISSIPATING TUESDAY.
WEAK HIGH PRESSURE IS EXPECTED TO PREVAIL BY MID WEEK. TEMPERATURES
WILL BE AT OR BELOW CLIMO THROUGH THE PERIOD.
&&
.AVIATION /16Z WEDNESDAY THROUGH SUNDAY/...
VFR THROUGH 12Z THURSDAY. POTENTIAL FOR AFTERNOON AND EVENING
SHOWERS AND TSTMS TODAY IS TOO LOW FOR ANY MENTIONS IN THE CURRENT
TAF CYCLE AT THIS TIME...ESPECIALLY WITH UNCERTAINTIES WITH
TIMING AND COVERAGE.
EXTENDED AVIATION OUTLOOK...BRIEF FLIGHT RESTRICTIONS POSSIBLE IN
AFTERNOON SHOWERS/THUNDERSTORMS...ESPECIALLY THIS WEEKEND.
&&
.MARINE...
THE COASTAL WATERS SYNOPTIC PATTERN IS NOT CHANGING MUCH AND
MARINERS FAMILIAR WITH THE SUMMER PATTERNS WILL NOT GET ANY BIG
SURPRISES THROUGH TONIGHT. SOUTH/SW SEA BREEZE CIRCULATIONS THIS
AFTERNOON AND SW NOCTURNAL SURGES WILL PUSH SPEEDS INTO THE 15-20
KT RANGE WITH SOME HIGHER GUSTS AT FAVORED AREAS SUCH AS THE
CHARLESTON LAND/SEA INTERFACE. SEAS WILL BE 2-4 FT ON
AVERAGE...HIGHEST WELL OFFSHORE. WAVES IN THE HARBOR WILL BE 1 TO
2 FT THROUGH THIS EVENING.
THURSDAY THROUGH MONDAY...ATLANTIC HIGH PRESSURE WILL PREVAIL OVER
THE COASTAL WATERS WHILE A TROUGH OF LOW PRESSURE PERSISTS INLAND
THROUGH THE REMAINDER OF THE WEEK. A COLD FRONT IS EXPECTED TO
APPROACH THE WATERS OVER THE WEEKEND AND EVENTUALLY STALL AND
DISSIPATE EARLY NEXT WEEK. TIGHTENED PRESSURE GRADIENT WILL KEEP
WINDS FAIRLY ELEVATED THROUGH THE PERIOD. NOCTURNAL JETTING AND
AFTERNOON SEA BREEZE CIRCULATIONS WILL RESULT IN SOUTH/SOUTHWEST
WINDS PEAKING AROUND 15-20 KT...ESPECIALLY ACROSS THE CHARLESTON
COUNTY COASTAL WATERS. GUSTS MAY REACH NEAR SMALL CRAFT ADVISORY
CRITERIA OF 25 KT AT TIMES...AND HEADLINES MAY NEED TO BE
CONSIDERED. SEAS WILL MAINLY BE 2-4 FEET...BUT MAY REACH 5-6 FEET IN
THE OUTER PORTIONS OF THE WATERS DURING SURGES.
&&
.CLIMATE...
RECORD HIGH MINIMUMS FOR JUNE 24TH...
KCHS...79 SET IN 1998.
KCXM...85 SET IN 1998.
KSAV...80 SET IN 1914.
RECORD HIGH MINIMUMS FOR JUNE 25TH...
KCHS...79 SET IN 2010.
KCXM...83 SET IN 1998.
KSAV...80 SET IN 1914.
&&
.CHS WATCHES/WARNINGS/ADVISORIES...
GA...HEAT ADVISORY UNTIL 7 PM EDT THIS EVENING FOR GAZ087-088-
099>101-114>119-137>141.
SC...HEAT ADVISORY UNTIL 7 PM EDT THIS EVENING FOR SCZ040-042>045-
047>052.
MARINE...NONE.
&&
$$
SYNOPSIS...
NEAR TERM...
SHORT TERM...ECT
LONG TERM...ECT
AVIATION...
MARINE...
CLIMATE...
AREA FORECAST DISCUSSION
NWS CHARLESTON SC
1022 AM EDT WED JUN 24 2015
.SYNOPSIS...
ATLANTIC HIGH PRESSURE WILL PREVAIL MUCH OF THIS WEEK WHILE A TROUGH
OF LOW PRESSURE PERSISTS INLAND. A COLD FRONT WILL STALL TO THE NORTH
LATE WEEK INTO THE WEEKEND BEFORE FINALLY CROSSING THE AREA LATE
SUNDAY. THE FRONT MAY STALL JUST OFFSHORE BEFORE DISSIPATING EARLY
NEXT WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
AFTER OUR BRIEF RESPITE FROM THE EXTREME HEAT AND HUMIDITY
COMBINATION YESTERDAY...IT/S BACK TO THE OPPRESSIVE AND STICKY
CONDITIONS THAT WE HAVE SEEN MUCH OF THE PAST 2 WEEKS. TEMPS ARE
RUNNING ON AVERAGE ABOUT 2-3F WARMER THAN 24 HOURS AGO...AND WITH
850 MB TEMPS OF 19-20C AND PLENTY OF INSOLATION...WE/RE ON OUR WAY
TO THE MID AND UPPER 90S INLAND FROM US-17. A FEW SPOTS MIGHT EVEN
PEAK AT THE CENTURY MARK. DEW POINTS WILL MIX OUT A BIT
INLAND...BUT WILL POOL BEHIND THE SEA BREEZE...WHICH SUPPORTS MOST
HEAT INDICES AS HIGH AS 105-109F...BUT A FEW SPOTS OF THE COASTAL
CORRIDOR WILL MAX OUT AT 110-112F AROUND THE TIME OF THE SEA
BREEZE PASSAGE. OUR HEAT ADVISORY WILL OBVIOUSLY REMAIN ACTIVE.
THE FORECAST FOR HOW CONVECTION WILL PAN OUT IS FAR FROM CERTAIN
GIVEN A WIDE DISPARITY IN VARIOUS MODELS. WE STILL HAVE A SUBTLE
WEAKNESS IN THE RIDGING ALOFT...BUT THAT LOOKS TO BE JUST OFF THE
COAST. THERE WILL BE VARIOUS MESO-SCALE BOUNDARIES SUCH S OUTFLOW
FROM EARLIER MCS THAT MOVED OFF THE MID-ATLANTIC AND ANOTHER FROM
ALABAMA. THERE IS ALSO THE EVER PRESENT PIEDMONT TROUGH AND THE
SEA BREEZE BOUNDARY. THESE FACTORS SHOULD PROVIDE THE NECESSARY
INITIATION...BUT THERE IS STILL A STRONG 3-5C CAP AND UNFAVORABLE
MID LEVEL LAPSE RATES WITH WARM 500 MB TEMPS...IMPLYING THAT
STORMS MAY HAVE A DIFFICULT TIME IN ATTAINING MUCH VERTICAL
GROWTH. ON THE FAVORABLE SIDE OUR LOW LEVEL LAPSE RATES ARE
FAVORABLE AND THERE IS PLENTY OF INSTABILITY WITH SBCAPES FORECAST
TO REACH 4000-4500 J/KG AND LIFTED INDEX OF -6 TO -8C. LOOK FOR
CONVECTION TO GET GOING AROUND 1-2 PM AS WE HIT OUR CONVECTIVE
TEMP IN THE MID 90S.
FOR THE MOMENT A PULSE TYPE ENVIRONMENT SEEMS A MORE LIKELY
CONVECTIVE MODE RATHER THAN MULTI-CELLULAR...BUT IF BOUNDARY
INTERACTIONS AND MERGERS TAKE PLACE THAT COULD CHANGE. WE/LL
MAINTAIN A PROBABILITY FORECAST OF 20-30 PERCENT...HIGHEST INLAND
AND MAINTAIN A CLOSE WATCH ON MESO-SCALE TRENDS TO SEE IF WE NEED
TO RAISE POPS.
DCAPES OF 1000-1200 J/KG AND WINDEX VALUES OF 65 KT WOULD SUPPORT
STRONG DOWNBURST WINDS...AIDED BY PRECIP LOADING WITH PWATS CLOSE
TO THE 90TH PERCENTILE FOR LATE JUNE. OTHER HAZARDS INCLUDE
FREQUENT LIGHTNING STRIKES...VERY HEAVY RAINS DUE TO A STORM
MOTION OF ONLY AROUND 5 MPH AND SHOULD ANY TALL STORMS DEVELOP
THERE IS ALSO HAIL RISK. PROBABILITY OF SEVERE WEATHER IS STILL
TOO LOW TO INCLUDE IN THE HAZARDOUS WEATHER OUTLOOK...MOST NOTABLY
DUE TO THE HRRR SHOWING LITTLE IN THE WAY OF CONVECTIVE
ORGANIZATION.
CONDITIONS SHOULD BE MAINLY QUIET TONIGHT WITH PARTLY CLOUDY SKIES
AND LOWS A BIT WARMER THAN WEDNESDAY MORNING...ESPECIALLY IF TSTMS
COVERAGE IS LOWER END TODAY.
&&
.SHORT TERM /THURSDAY THROUGH SATURDAY/...
THURSDAY...PERSISTENT MID LEVEL RIDGE WILL HOLD FAIRLY STRONG FOR
ONE MORE DAY...ALTHOUGH SUBTLE WEAKENING WILL BEGIN TO OCCUR. THE
SURFACE PATTERN WILL CONTINUE TO BE FAIRLY STATIC AS THE AREA
REMAINS ON THE WESTERN PERIPHERY OF ATLANTIC HIGH PRESSURE WITH A
PIEDMONT TROUGH SITUATED INLAND. HIGH TEMPERATURES IN THE MID/UPPER
90S AWAY FROM THE COAST WILL COMBINE WITH MODERATE HUMIDITY LEVELS
TO PRODUCE HEAT INDICES OF 105-108 IN THE AFTERNOON. THUS A HEAT
ADVISORY WILL LIKELY BE NEEDED. LARGE SCALE FORCING WILL LARGELY BE
MISSING HOWEVER CONVECTION WILL DEVELOP AS A RESULT OF SEA BREEZE
AND/OR CONVERGENCE ALONG SURFACE TROUGH. FORECAST SURFACE BASED
CAPE NEAR 3000 J/KG MAY SUPPORT A FEW STRONGER POSSIBLY SEVERE
STORMS...WITH GUSTY WINDS THE PRIMARY THREAT GIVEN DCAPE VALUES IN
EXCESS OF 1000 J/KG. THURSDAY NIGHT...SURFACE LOW PRESSURE WILL
CROSS THE MID-ATLANTIC STATES ABSORBING THE PIEDMONT TROUGH. AN
ATTENDANT FRONT WILL STALL NORTH OF THE AREA. LOWS WILL BE QUITE
MILD RANGING FROM THE MID 70S INLAND TO AROUND 80 ALONG THE COAST.
FRIDAY...AN AREA OF LOW PRESSURE WILL DEVELOP OVER THE CAROLINAS
ALONG THE AFOREMENTIONED STALLED FRONT. DEEP MOISTURE AND PROXIMITY
TO BOUNDARY WILL ALLOW FOR HIGHER COVERAGE OF SHOWERS AND
THUNDERSTORMS. FORECAST CURRENTLY FEATURES HIGH CHANCE POPS OVER
MUCH OF THE AREA DURING PEAK HEATING HOURS. A FEW STRONGER STORMS
WILL BE POSSIBLE ESPECIALLY IN THE NORTHERN ZONES WHERE INSTABILITY
AND MID LEVEL ENVIRONMENT IS MORE FAVORABLE...WITH GUSTY WINDS
PRIMARY THREAT. FORECAST HEAT INDICES MAY BRIEFLY REACH THE LOCAL
HEAT ADVISORY CRITERIA OF 105 IN THE AFTERNOON WITH HIGH
TEMPERATURES IN THE LOW/MID 90S...HOWEVER DURATION AND AREAL EXTENT
WILL BE MARGINAL AT BEST AND GIVEN EXPECTED CONVECTION...THINK A
HEAT ADVISORY WILL LIKELY NOT BE NEEDED. CONVECTION MAY LINGER INTO
THE OVERNIGHT PERIOD...WITH FOCUS SHIFTING MORE TO THE COASTAL
WATERS. LOWS WILL AGAIN BE IN THE MID TO UPPER 70S.
SATURDAY...THE UPPER LEVEL PATTERN WILL BECOME MUCH MORE AMPLIFIED
AS DEEPENING TROUGH AND ASSOCIATED VORT MAX DIGS INTO THE GREAT
LAKES REGION. THIS WILL HELP SEND ANOTHER AREA OF LOW PRESSURE
TOWARDS EAST COAST WHICH WILL EVENTUALLY ENGULF THE STATIONARY
FRONT/LOW. BETTER UPPER SUPPORT...DEEP MOISTURE AND VARIOUS SURFACE
BOUNDARIES WILL ALLOW FOR A FAIRLY ACTIVE DAY WITH STRONGER STORMS
POSSIBLE GIVEN DECENT SHEAR AND FORECAST INSTABILITY. HIGH
TEMPERATURES WILL MAINLY BE IN THE LOW 90S.
&&
.LONG TERM /SATURDAY NIGHT THROUGH TUESDAY/...
BROAD UPPER TROUGH WILL ENCOMPASS THE EASTERN U.S. THROUGH THE LONG
TERM PERIOD. A POTENT SHORTWAVE WILL SEND AN AREA OF LOW PRESSURE
AND ATTENDANT FRONT THROUGH THE FORECAST AREA ON SUNDAY. GIVEN
FORCING FROM UPPER JET...SHORTWAVE ENERGY AND COLD FRONT...IT SHOULD
BE A PRETTY ACTIVE DAY ESPECIALLY GIVEN DECENT SHEAR AND DEEP
MOISTURE. THE FRONT WILL LIKELY PUSH OFF THE COAST EARLY
MONDAY...AND REMAIN STATIONARY OFFSHORE BEFORE DISSIPATING TUESDAY.
WEAK HIGH PRESSURE IS EXPECTED TO PREVAIL BY MID WEEK. TEMPERATURES
WILL BE AT OR BELOW CLIMO THROUGH THE PERIOD.
&&
.AVIATION /14Z WEDNESDAY THROUGH SUNDAY/...
VFR THROUGH 12Z THURSDAY. POTENTIAL FOR AFTERNOON AND EVENING
SHOWERS AND TSTMS TODAY IS TOO LOW FOR ANY MENTIONS IN THE CURRENT
TAF CYCLE AT THIS TIME...ESPECIALLY WITH UNCERTAINTIES WITH
TIMING AND COVERAGE.
EXTENDED AVIATION OUTLOOK...BRIEF FLIGHT RESTRICTIONS POSSIBLE IN
AFTERNOON SHOWERS/THUNDERSTORMS...ESPECIALLY THIS WEEKEND.
&&
.MARINE...
THE COASTAL WATERS SYNOPTIC PATTERN IS NOT CHANGING MUCH AND
MARINERS FAMILIAR WITH THE SUMMER PATTERNS WILL NOT GET ANY BIG
SURPRISES THROUGH TONIGHT. SOUTH/SW SEA BREEZE CIRCULATIONS AND SW
NOCTURNAL SURGES WILL PUSH SPEEDS INTO THE 15-20 KT RANGE WITH
SOME HIGHER GUSTS AT FAVORED AREAS SUCH AS THE CHARLESTON LAND/SEA
INTERFACE WITH SEAS 2-4 FT ON AVERAGE...HIGHEST WELL OFFSHORE.
WAVES IN THE HARBOR WILL BUILD TO 1 TO 2 FT THROUGH THIS EVENING.
THURSDAY THROUGH MONDAY...ATLANTIC HIGH PRESSURE WILL PREVAIL OVER
THE COASTAL WATERS WHILE A TROUGH OF LOW PRESSURE PERSISTS INLAND
THROUGH THE REMAINDER OF THE WEEK. A COLD FRONT IS EXPECTED TO
APPROACH THE WATERS OVER THE WEEKEND AND EVENTUALLY STALL AND
DISSIPATE EARLY NEXT WEEK. TIGHTENED PRESSURE GRADIENT WILL KEEP
WINDS FAIRLY ELEVATED THROUGH THE PERIOD. NOCTURNAL JETTING AND
AFTERNOON SEA BREEZE CIRCULATIONS WILL RESULT IN SOUTH/SOUTHWEST
WINDS PEAKING AROUND 15-20 KT...ESPECIALLY ACROSS THE CHARLESTON
COUNTY COASTAL WATERS. GUSTS MAY REACH NEAR SMALL CRAFT ADVISORY
CRITERIA OF 25 KT AT TIMES...AND HEADLINES MAY NEED TO BE
CONSIDERED. SEAS WILL MAINLY BE 2-4 FEET...BUT MAY REACH 5-6 FEET IN
THE OUTER PORTIONS OF THE WATERS DURING SURGES.
&&
.CLIMATE...
RECORD HIGH MINIMUMS FOR JUNE 24TH...
KCHS...79 SET IN 1998.
KCXM...85 SET IN 1998.
KSAV...80 SET IN 1914.
RECORD HIGH MINIMUMS FOR JUNE 25TH...
KCHS...79 SET IN 2010.
KCXM...83 SET IN 1998.
KSAV...80 SET IN 1914.
&&
.CHS WATCHES/WARNINGS/ADVISORIES...
GA...HEAT ADVISORY UNTIL 7 PM EDT THIS EVENING FOR GAZ087-088-
099>101-114>119-137>141.
SC...HEAT ADVISORY UNTIL 7 PM EDT THIS EVENING FOR SCZ040-042>045-
047>052.
MARINE...NONE.
&&
$$
SYNOPSIS...
NEAR TERM...
SHORT TERM...ECT
LONG TERM...ECT
AVIATION...
MARINE...
CLIMATE...
AREA FORECAST DISCUSSION
NWS NEW ORLEANS LA
831 AM CDT WED JUN 24 2015
...SOUNDING DISCUSSION...
THE SOUNDING THIS MORNING DEPICTS AN ATMOSPHERE THAT IS MOIST AND
UNSTABLE. PW IS ABOVE AVERAGE AT 1.96 INCHES AND MIXED LAYER CAPE
IS 1000 J/KG... MOST UNSTABLE CAPE IS 2700 J/KG. A SHALLOW
TEMPERATURE INVERSION IS AT THE SFC TO 1500 FT AND WILL MIX OUT
QUICKLY. WINDS ARE LIGHT AND NORTHEASTERLY FROM THE SFC TO 500 MB
THEN BECOME EASTERLY THROUGH THE REST OF THE PROFILE. CONVECTIVE
TEMPERATURE ON THE SOUNDING IS LISTED AT 93F AND STORMS ARE
EXPECTED TO FIRE WITH DAYTIME HEATING SIMILAR TO THE PAST FEW
DAYS.
KRAUTMANN
&&
.PREV DISCUSSION... /ISSUED 333 AM CDT WED JUN 24 2015/
SHORT TERM...
CURRENTLY MONITORING TRENDS AND EVOLUTION OF CONVECTION OVER
ALABAMA AND NORTHERN MISSISSIPPI THIS MORNING AS A RESULT OF A
LARGE OUTFLOW BOUNDARY THAT IS MOWING SOUTHWEST THROUGH AN
UNSTABLE AIR MASS. THE SOUTHERN ALABAMA ACTIVITY HAS CONGEALED
INTO A RATHER LARGE AND EXPANDING MCS WITH PLENTY OF IN-CLOUD
LIGHTNING AND ONLY ABOUT 10 PERCENT CLOUD-TO-GROUND PRODUCTION.
THE LARGER SCALE MODELS ARE NOT HANDLING THIS DEVELOPMENT
PARTICULARLY WELLL BUT THE HIGHER RESOLUTION SHORT-RANGE
CONVECTIVE BASED MODELS LIKE THE HRRR AND WRF ARE LATCHED IN ON
CURRENT TRENDS. AS A RESULT...HAVE OPTED TO INCREASE RAIN CHANCES
TO 50 PERCENT WITH EARLY ONSET ON THE MISSISIPPI COAST...AND
EARLIER THAN TYPICAL IN LOUISIANA BY MID-MORNING. HIGH CAPE AND
LOW SHEAR ENVIRONMENT WOULD SUGGEST MAIN THREAT TO BE WET
MICROBURSTS OVER LAND AREAS AFTER SUNRISE AND TYPE II WATERSPOUT
PRODUCTION IN THE COASTAL WATERS AND POSSIBLY OVER AREA BAYS AND
INLAND WATERWAYS. RAINFALL CAN ALSO BE EFFICIENT WITH SOME
LOCALIZED PONDING POSSIBLE...THOUGH MUCH OF THE RAINFALL WILL BE
ANVIL DECAY TYPE AWAY FROM THE PRIMARY CORES. MOVEMENT AND
PROPAGATION DUE TO OUTFLOW SHOULD BE ABLE TO KEEP STORM TOTAL
RAINFALL AT MANAGEABLE LEVELS TODAY. CONVECTION WILL ALSO LIKELY
DISRUPT THE SEA BREEZE CYCLE TODAY...OR AT LEAST GREATLY DELAY THE
ONSET UNTIL MUCH LATER IN THE AFTERNOON AS THE AIR MASS WILL NEED
TIME TO RECOVER AFTER MORNING CONVECTION AND INDUCTION OF DEEPER
NORTHERLY FLOW ALOFT. OTHERWISE...TEMPERATURES OF MODEL CONSENSUS
WILL BE PROVIDED BUT MAY BE IN LINE FOR SOME BUSTS OR AT LEAST
ATYPICAL DIURNAL TREND BEHAVIORS DUE TO CLOUD COVER EARLY ON.
FRIDAY COULD BE A REPEAT AS A COLD POOL REMAINS IN PLACE ALOFT AND
NOCTURNAL CONVECTION MAY ONCE AGAIN ERUPT DUE TO OUTFLOW FEATURES
GENERATED FROM CONVECTION ALONG THE FRINGES OF UPPER RIDGE FARTHER
NORTH.
LONG TERM...
MODELS ARE STILL IN VERY GOOD AGREEMENT WITH LARGE SCALE TROUGHING
TO TAKE PLACE OVER THE WEEKEND. THIS SHOULD ALLOW A SURFACE
FRONTAL FEATURE TO SETTLE INTO THE AREA...POSSIBLY DROPPING INTO
THE NORTH GULF LATE SUNDAY...AND PROVIDING A GENERALLY COOLING TO
AT LEAST NEAR NORMAL TEMPERATURES FOR NEXT WEEK. THE PATTERN WOULD
ALSO FAVOR INCREASED CHANCES AT RAINFALL EACH DAY POSSIBLY IN MCS
FASHION IN BASE OF TROUGH BY MID-WEEK. CONSENSUS MODEL GUIDANCE ON
TEMPERATURES AND POPS DURING THE EXTENDED PORTION. 24/RR
AVIATION...
EXPECT VFR CONDITIONS TO PREVAIL THROUGH THE TAF PERIOD WITH
GENERALLY LIGHT AND VARIABLE WINDS. HOWEVER OVERNIGHT CONVECTION
FROM SOUTH CENTRAL ALABAMA CONTINUES TO DRIFT TOWARDS THE FORECAST
AREA THIS MORNING AND WILL PROBABLY HAVE TO AMEND TAFS BEFORE THE
12Z ISSUANCE TO ADD THUNDERSTORMS INTO THE KGPT TAF AND TO START
CONVECTION EARLIER AT KMCB AND KASD. WILL HAVE TO CONTINUE TO WATCH.
GUSTY WINDS AND FREQUENT LIGHTNING WILL BE THE MAIN THREATS. VSBY
WITHIN THUNDERSTORMS COULD DROP TO IFR CONDITIONS BUT OUTSIDE
OF CONVECTION EXPECT MOSTLY VFR CONDITIONS. 13/MH
MARINE...
A WEAK SURFACE RIDGE REMAINS ACROSS THE REGION WITH NO
MAJOR CHANGES TO THE FORECAST AS WINDS WILL BE GENERALLY 10 KNOTS OR
LESS. ISOLATED TO SCATTERED CONVECTION IS POSSIBLE EACH AFTERNOON.
THE PATTERN SHOULD BE BROKEN BY AN APPROACHING COLD FRONT ON
SATURDAY AS WIND SPEEDS AND SEAS WILL BEGIN TO PICK UP. 13/MH
DECISION SUPPORT...
DSS CODE...BLUE.
DEPLOYED...NONE.
ACTIVATION...NONE.
ACTIVITIES...RIVER FLOOD WARNINGS ON MISSISSIPPI RIVER.
DECISION SUPPORT SERVICES (DSS) CODE LEGEND
GREEN = NO WEATHER IMPACTS THAT REQUIRE ACTION
BLUE = LONG FUSED WATCH/WARNING/ADVISORY IN EFFECT OR HIGH
VISIBILITY EVENT
YELLOW = HEIGHTENED IMPACTS WITH SHORT FUSED WATCH/WARNING/ADVISORY
ISSUANCES; RADAR SUPPORT
ORANGE = HIGH IMPACTS - SLIGHT TO MODERATE RISK SEVERE; NEARBY
TROPICAL EVENTS; HAZMAT OR OTHER LARGE EPISODES
RED = FULL ENGAGEMENT FOR MODERATE RISK SVR AND/OR DIRECT
TROPICAL THREATS; EVENTS OF NATIONAL SIGNIFICANCE
&&
.PRELIMINARY POINT TEMPS/POPS...
MCB 94 74 91 74 / 50 30 40 20
BTR 95 76 92 75 / 50 30 40 10
ASD 94 77 91 77 / 50 20 40 20
MSY 94 78 91 77 / 50 20 40 20
GPT 93 79 91 78 / 50 30 40 20
PQL 93 77 91 78 / 50 30 30 20
&&
.LIX WATCHES/WARNINGS/ADVISORIES...
LA...NONE.
GM...NONE.
MS...NONE.
GM...NONE.
&&
$$
AREA FORECAST DISCUSSION...UPDATED
NWS MARQUETTE MI
1122 AM EDT WED JUN 24 2015
.UPDATE...
ISSUED AT 1120 AM EDT WED JUN 24 2015
ONLY MINOR TWEAKS TO THE GOING FORECAST WITH THIS MORNINGS UPDATE.
A SHORTWAVE MOVING THROUGH NORTHERN MINNESOTA HAS SPREAD SOME
SHOWERS AND A FEW THUNDERSTORMS EAST-SOUTHEAST INTO WESTERN LAKE
SUPERIOR...BETWEEN THE APOSTLE ISLANDS AND ISLE ROYALE. EXPECT THIS
WAVE TO CONTINUE TO THE EAST AND SPREAD SHOWERS ACROSS THE NORTHERN
HALF OF THE KEWEENAW PENINSULA EARLY THIS AFTERNOON. THE QUESTION
FOR THIS AFTERNOON WILL BE THE AMOUNT OF SHOWER DEVELOPMENT THAT
WILL OCCUR OVER THE LAND AREAS...WHICH WILL BE AIDED BY LAKE
BREEZES. SURFACE DEWPOINTS AT THE 11AM WERE IN THE MID-UPPER
50S...BUT THE 12Z KGRB SOUNDING AND RAP ANALYSIS SOUNDINGS SHOW A
DECENT POCKET OF DRY AIR JUST ABOVE THE SURFACE AND THROUGH
800MB/7KFT. EXPECT THE SUN THAT IS OCCURRING OVER THE AREA TO AID
MIXING OF THAT DRIER AIR TO THE SURFACE OVER THE NEXT COUPLE OF
HOURS...WHICH WILL LIMIT THE INSTABILITY OVER THE AREA (DEWPOINTS
FALLING INTO THE LOWER 50S AND PROBABLY UPPER 40S TOWARDS THE
WISCONSIN BORDER). WHILE THERE WILL BE ENOUGH MOISTURE ABOVE THAT
DRY AIR TO DEVELOP CLOUDS AND LIKELY SOME SHOWERS...CONFIDENCE IS
LOWER ON WIDESPREAD SHOWERS AND HEAVIER RAIN. MODIFIED SOUNDINGS TO
EXPECTED AFTERNOON T/TD VALUES CONTINUES TO SHOW 500-600J/KG OF
MLCAPE...SO THUNDER REMAINS POSSIBLE ALONG WITH BRIEF GUSTY WINDS
DUE TO ABUNDANT LOW LEVEL DRY AIR PUSHING DCAPE VALUES OVER 800-
900J/KG OVER AT LEAST THE SOUTHERN HALF OF THE CWA. OVERALL EXPECT
THE GREATEST FOCUS OF SHOWERS TO BE OVER THE INTERIOR CENTRAL CWA
WHEN THEY DEVELOP AROUND MID AFTERNOON AND THEN MOVE TO THE
SOUTHEAST AROUND 20-25KTS.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 411 AM EDT WED JUN 24 2015
A COLD FRONT AND A SUBTLE UPPER SHORTWAVE WILL MOVE THROUGH TODAY.
THESE FEATURES AND LAKE BREEZE FORMATION WILL PROVIDE FORCING FOR
CONVECTION MAINLY INLAND FROM THE GREAT LAKES. SBCAPE VALUES SHOULD
BE IN THE 500-800J/KG RANGE INLAND...WITH RELATIVELY WEAK SHEAR DUE
TO NEARLY CALM WINDS AT AND BELOW 800MB. INVERTED V SOUNDINGS WITH
DRY LOW LEVELS AND EVEN AN INDICATION OF AN EML MAY LEAD TO SOME
GUSTY WINDS UNDER ANY COLLAPSING STORMS...BUT SEVERE IS NOT EXPECTED
AS BEST CONVECTION SHOULD BE WHERE LOW LEVEL MOISTURE IS
GREATER...AWAY FROM THE WI BORDER. CONVECTION IS STILL EXPECTED
ALONG THE WI BORDER...JUST TO A LESSER EXTENT.
NOT SURE ON EXACTLY HOW THINGS PLAY OUT TONIGHT AS A SHORTWAVE
CURRENTLY NEAR THE MT/ALBERTA BORDER MOVES INTO OR NEAR THE CWA
WHILE A SFC TROUGH MOVES THROUGH. THE NAM...GFS...GEM AND ECMWF HAVE
PRECIP MOVING ALONG WITH THESE FEATURES THROUGH THE CWA...BUT A
COUPLE OF HIGH-RES MODELS DO NOT SHOW NEARLY THE EXTENT OF PRECIP.
AT THIS TIME...SIDED WITH THE MAJORITY OF MODELS AND HAVE HIGH
CHANCE TO LIKELY POPS...BUT IS IS ENTIRELY POSSIBLE THAT SOME
LOCATIONS WILL STAY DRY TONIGHT.
.LONG TERM...(THURSDAY THROUGH TUESDAY)
ISSUED AT 426 AM EDT WED JUN 24 2015
SEVERAL PERIODS OF LIGHT SHOWERS ARE EXPECTED ACROSS UPPER MICHIGAN
DURING THE LONG TERM PERIOD...FIRST WITH LINGERING SHOWERS ON
THURSDAY FROM A PASSING SHORTWAVE...AND AGAIN DURING THE LATER PART
OF THE WEEKEND AND INTO EARLY NEXT WEEK.
THURSDAY...PASSING SHORTWAVE IN A NW FLOW COULD ALLOW SOME ISOLD TO
SCT SHOWERS TO LINGER DURING THE MORNING INTO EARLY AFTERNOON HOURS
AS MODELS GENERALLY SHOW 200-400 J/KG MLCAPE FOR INSTABILITY OVER
INLAND LOCATIONS. OTHERWISE...CONFLUENT FLOW ALOFT AHEAD OF BUILDING
RIDGE AND ASSOC MID-LVL Q-VECT DIV/SUBSIDENCE SHOULD GENERALLY LEAD
TO DRYING CONDITIONS ESPECIALLY BY LATE AFTERNOON.
TEMPORARY SPLIT-FLOW PATTERN DEVELOPING WILL ALLOW AN AREA OF SFC
HIGH PRESSURE TO DROP SOUTHEAST ACROSS THE UPPER GREAT LAKES REGION
THU NIGHT AND PERSIST INTO SATURDAY RESULTING IN MAINLY DRY
CONDITIONS. 00Z NAM HINTS AT A FEW DIURNAL SHOWERS DEVELOPING ON
FRIDAY ALONG THE LAKE BREEZES BUT FOR NOW WL MAINTAIN DRY FCST AS
MID-LVLS WILL LIKELY BE TOO DRY FOR SHRA DEVELOPMENT. OTHERWISE
SHOULD SEE PARTLY CLOUDY TO MOSTLY CLEAR SKIES OVER THE AREA.
AMPLIFICATION OF UPSTREAM RIDGE OVER THE WRN CONUS ALONG WITH A
SERIES OF WAVES DIVING SOUTH THROUGH THE NRN AND CENTRAL PLAINS LATE
THIS WEEK WILL HELP AMPLIFY THE UPPER TROUGH OVER THE EASTERN HALF
OF THE CONUS FOR THIS WEEKEND. WHILE THE TROUGH WILL WEAKEN AND
SHIFT EAST INTO EARLY NEXT WEEK...A SERIES OF SHORTWAVES DROPPING
SOUTHEAST INTO THE GREAT LAKES REGION SUNDAY INTO TUESDAY WILL
REINFORCE THE UPPER TROUGH OVER THE GREAT LAKES REGION FOR NEXT
WEEK. THIS WILL YIELD NORMAL TO BELOW NORMAL TEMPERATURES ALONG WITH
PERIODS OF RAIN SHOWERS AND MAYBE EVEN A FEW THUNDERSTORMS.
ALSO SOMETHING TO WATCH...THE LATEST 00Z RUN OF THE ECMWF SHOWS 850
MB TEMPS PLUMMETING TO AROUND 1C BY NEXT TUE EVENING (THE LAST DAY
OF JUNE)...BRRR! THIS 00Z SOLUTION IS DEFINITELY MORE AMPLIFIED
WITH THE MID-UPR TROUGH INTO THE UPPER GREAT LAKES THAN EITHER THE
00Z GFS OR THE PREVIOUS 12Z ECMWF SOLN...ALLOWING A DIRECT PATH FOR
ARCTIC AIR TO DIVE SOUTH INTO THE REGION. AGAIN THIS IS JUST ONE
MODEL RUN...BUT IT WILL BE SOMETHING TO MONITOR OVER THE NEXT
SEVERAL MODEL RUNS AS A TREND TOWARD THIS MORE AMPLIFIED AND COLDER
SOLUTION COULD RESULT IN A BRIEF SPELL OF WELL BELOW NORMAL TEMPS
FOR THE MIDDLE OF NEXT WEEK.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z THURSDAY MORNING)
ISSUED AT 741 AM EDT WED JUN 24 2015
MAINLY VFR CONDITIONS AS HIGH BASED SHOWERS AND POSSIBLY SOME
THUNDER THIS AFTERNOON AND EARLY EVENING. ADDITIONAL SHOWERS WILL
MOVE IN FROM THE WEST THIS EVENING/TONIGHT...BRINGING SOME LOWERING
CIGS LATE TONIGHT.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 411 AM EDT WED JUN 24 2015
WINDS WILL REMAIN BELOW 20KTS INTO THE MIDDLE OF NEXT WEEK. A LOW
PRESSURE SYSTEM DEVELOPING IN THE CENTRAL PLAINS TODAY WILL SLIDE E
THROUGH FRIDAY...WHILE ELONGATING OVER THE TENNESSEE VALLEY. A HIGH
OVER W ONTARIO THURSDAY MORNING WILL REMAIN OVER THE W GREAT LAKES
THROUGH SATURDAY. THIS RIDGE WILL SLIDE SLOWLY TO THE SE SATURDAY
NIGHT INTO SUNDAY AS A LOW SLIDES ACROSS N ONTARIO.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
UPDATE...SRF
SHORT TERM...TITUS
LONG TERM...VOSS
AVIATION...TITUS
MARINE...TITUS
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
907 AM EDT WED JUN 24 2015
.SYNOPSIS...
HIGH PRESSURE WILL RESULT IN DRY WEATHER WITH INCREASING AMOUNTS
OF SUNSHINE THIS AFTERNOON. A PASSING WAVE OF LOW PRESSURE WILL
BRING SHOWERS THROUGH THE REGION LATE THURSDAY. OUR PATTERN WILL
REMAIN SLIGHTLY COOLER THAN NORMAL...AND UNSETTLED WITH PERIODIC
CHANCES OF SHOWERS THROUGH THE WEEKEND.
&&
.NEAR TERM /THROUGH TONIGHT/...
9 AM UPDATE...
VISIBLE SATELLITE IMAGERY SHOWS AN OVC LAYER OF STRATOCUMULUS
ACROSS NORTH CENTRAL NY TO THE CATSKILLS...EASTERN SOUTHERN TIER
OF NY AND SOUTH INTO THE POCONOS AND SCRANTON/WILKES BARRE AREAS
OF PA. THIS LAYER WAS BTWN 1800 AND 3000 FEET AND SLOWLY
DEVELOPING TO THE W-SW AS A LOW-LEVEL NW FLOW ASCENDS UP THE HILLS
OF C NY AND NE PA AND SATURATES OUT. THIS IS AIDED BY SOME
BOUNDARY LAYER HEATING. AS THE BNDRY LAYER HEATS AND GROWS INTO
THE AFTERNOON DRIER AIR FROM ABOVE WILL ENTRAIN DOWNWARD AND MUCH
OF THE CLOUDINESS WILL BREAK UP. MODEL SOUNDINGS FROM
NAM...GFS...RAP AND HRRR ALL SEEM TO QUICK TO MIX OUT THE OVC
LAYER. THE NAM4KM MODEL SOUNDINGS APPEAR TO HAVE THE BEST HANDLE
ON THE PRESENT SITUATION AND DELAY THE CLOUDS BREAKING UP INTO
THE AFTERNOON. SO WILL FOLLOW NAM 4KM. LOOKING AT THE CU RULE
WHICH TAKES THE 850 MB TEMP AND SUBTRACTS THE 1000 MB DWPT THE GFS...NAM
AND ECMWF SUGGEST A SCT CUMULUS LAYER THIS AFTERNOON AS THE BNDRY
LAYER REACHES ITS MAX HGHT PROBABLY ARND 5-6 KFT. SO WILL KEEP PC
SKIES BY MID AFTERNOON AS WE BELIEVE THE PRESENT OVC SC LAYER WILL
EVOLVE INTO SCT CU BY 19-20Z. ALSO ADJUSTED TEMPS DOWN A TAD TO
ACCOUNT FOR MORE CLOUD COVER. HARD TO BELIEVE IT IS LATE JUNE HERE
AT BGM AS THE SKY LOOKS VERY MUCH LIKE NOVEMBER NOW!!
4 AM UPDATE...
NORTHWEST WINDS WILL CONTINUE TO ADVECT IN A DRY AIR MASS...AS
HIGH PRESSURE SPREADS IN FROM THE MIDWEST. PLENTY OF SUNSHINE CAN
BE EXPECTED...WITH HIGHS TODAY MAINLY IN THE 70S...A FEW TO
SEVERAL DEGREES SHORT OF CLIMATOLOGY. DEWPOINTS WILL ONLY BE LOW
TO MID 50S...WHICH FOR MOST IS VERY COMFORTABLE.
QUIET CONDITIONS PERSIST TONIGHT WITH A MAINLY CLEAR SKY...THEN
INCREASING HIGH THIN CLOUDS TOWARDS DAWN AHEAD OF THE NEXT
DISTURBANCE...WITH LOWS IN THE 50S.
&&
.SHORT TERM /THURSDAY THROUGH FRIDAY NIGHT/...
4 AM UPDATE...
THURSDAY STARTS OFF FAIRLY QUIET...BUT A NORTHERN STREAM SUMMER
CLIPPER OF SORTS...WILL ARRIVE FROM THE UPPER MIDWEST MID TO LATE
AFTERNOON. MEANWHILE...SOUTHERN STREAM WARM FRONT WILL ATTEMPT TO
LIFT NORTHWARD FROM THE MIDATLANTIC STATES BUT WILL FALL SHORT.
BAROCLINIC LIFT WILL OCCUR NORTH OF THAT WARM FRONT...AS THE
NORTHERN STREAM WAVE ALSO PASSES. HOWEVER...INSTABILITY LOOKING
MORE DOUBTFUL...AND THUS EXPECTING MAINLY JUST SHOWERS OR EVEN
STRATIFORM RAIN INSTEAD OF THUNDER. I INCLUDE ONLY A SLIGHT CHANCE
OF THUNDER IN NORTHEAST PA AT THIS TIME...TO ACCOMPANY LIKELIHOOD
OF SHOWERS LATE THURSDAY INTO THURSDAY EVENING. FURTHER
NORTH...CHANCES DROP OFF...TO THE POINT THAT SOME PORTIONS OF
CENTRAL NY MAY RECEIVE VERY LITTLE RAIN FROM THIS SYSTEM.
00Z NAM APPEARS TO BE SUFFERING FROM CONVECTIVE FEEDBACK GIVEN
THE FAIR AMOUNT OF STABILITY...AND THUS ITS QPF AMOUNTS LOOK
UNREASONABLE. SOMETHING ON THE ORDER OF UP TO A FEW TENTHS OF AN
INCH...OR CONSENSUS OF NON-NAM MODELS...APPEARS MORE PROBABLE...AND
THOSE AMOUNTS FOCUSED MAINLY TWIN TIERS SOUTHWARD.
WITH TIME...EASTERN UPPER TROUGH WILL BE SETTING UP. SO WHILE
CHANCES OF ADDITIONAL SHOWERS FRIDAY-FRIDAY NIGHT ARE NOT THAT
HIGH...WE COULD STILL HAVE SCATTERED SHOWERS POPPING UP WITH WEAK
SHORTWAVES EMBEDDED IN THE LARGER DEVELOPING TROUGH...COMBINED
WITH DIURNAL HEATING.
TEMPERATURES THROUGH THE PERIOD WILL GENERALLY BE A FEW TO SEVERAL
DEGREES BELOW NORMAL VALUES.
&&
.LONG TERM /SATURDAY THROUGH TUESDAY/...
115 PM EDT UPDATE...
CLOSELY FOLLOWED WPC GUIDANCE.
A VERY ACTIVE PATTERN CONTINUES AND WILL REMAIN IN PLACE THRU THE
END OF THE FORECAST PERIOD. THIS PATTERN CONSISTS OF TROUGHING OVER
THE EAST AND RIDGING OVER THE WEST. KEPT A CHANCE FOR PRECIP OVER
THE CWA THRU THE WHOLE PERIOD. MULT WAVES WILL RIDE AROUND THE
TROUGH AND CREATE ENOUGH UPPR LVL SUPPORT FOR SHOWERS. THIS PATTERN
WILL ALSO CREATE CLOUDY SKIES ALONG WITH BELOW NORMAL TEMPS FOR THIS
TIME OF YR.
&&
.AVIATION /13Z WEDNESDAY THROUGH SUNDAY/...
PATCH OF SC OVER ERN NY BRINGING MVFR CIGS TO SYR AND RME THIS
MRNG. BRIEF FOG PSBL WEST OF THE CLDS...ESP AT ITH...OTRW HIPRES
WILL BRING MAINLY CLR SKIES AND VFR CONDS TO THE TAF SITES FOR THE
NEXT 24 HRS. WINDS WILL BE WEST BHD YSTRDYS COLD FNT...GNRLY 10
KTS OR LESS.
.OUTLOOK...
THURS AFTN/FRI/SAT/SUN...CHANCE OF SHRA AND ASSOCIATED
RESTRICTIONS.
&&
.BGM WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NY...NONE.
&&
$$
SYNOPSIS...PCF/DJN
NEAR TERM...DJN/MDP
SHORT TERM...MDP
LONG TERM...MDP
AVIATION...DGM
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
1137 AM EDT WED JUN 24 2015
.SYNOPSIS...
HOT AND HUMID CONDITIONS WILL PERSIST THROUGH THE END OF THE WEEK
WITH ISOLATED SHOWERS AND THUNDERSTORMS PRIMARILY DURING THE
AFTERNOONS AND EVENINGS. MUCH COOLER TEMPERATURES ALONG WITH A
BETTER CHANCE OF SHOWERS AND THUNDERSTORMS WILL DEVELOP THIS
WEEKEND. A DRYING TREND WILL BEGIN NEXT WEEK AS FRONT STALLED IN
THE AREA DISSIPATES AND HIGH PRESSURE RETURNS.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 1000 AM WEDNESDAY...A HEAT ADVISORY REMAINS IN EFFECT
TODAY AS TEMPS SOAR INTO AND THROUGH THE 90S ONCE AGAIN AND
COMBINE WITH A VERY HUMID AIR MASS TO CREATE DANGEROUS HEAT. A
COLD FRONT EXTENDING FROM THE MOUNTAINS OF WESTERN NC E-NE TOWARD
NC/VA COAST THIS MORNING WILL PUSH ONLY SLOWLY SOUTH AS IT WASHES
OUT. THIS WILL HELP TO ADVECT SLIGHTLY DRIER AIR IN FROM THE N-NW
AND WILL CREATE A TIGHTER GRADIENT FLOW PRODUCING ENHANCED LOW
LEVEL CONVERGENCE ALONG TROUGH AHEAD OF IT. OVERALL IT WILL JUST
PRODUCE A WIND SHIFT TO A MORE N-NE DIRECTION BEHIND IT AS IT
REACHES DOWN ALONG THE NC/SC BORDER CUTTING ACROSS OUR LOCAL
FORECAST AREA THIS AFTERNOON. THE MUCH LOWER DEWPOINT AIR WILL
REMAIN WELL TO THE NORTH AS SW FLOW AT THE SURFACE CONTINUES TO
KEEP A MOISTURE RICH AIR MASS OVER MUCH OF LOCAL FORECAST
AREA....WITH DEWPOINT TEMPS INTO THE 70S THIS MORNING AND PCP
WATER VALUES NEAR 2 INCHES. ML CAPE VALUES WERE REACHING CLOSE TO
4000 J/KG WITH LI VALUES TO -11. THIS UNSTABLE ENVIRONMENT WILL
INCREASE THE POTENTIAL FOR CONVECTIVE DEVELOPMENT THIS AFTERNOON.
OVERALL THE FORCING WILL BE SHALLOW WITH STEEP LOW LEVEL LAPSE
RATES TO INITIATE STORM DEVELOPMENT THIS AFTERNOON. THE FOCUS OF
CONVECTION WILL BE ALONG THIS SFC BOUNDARY AS IT SHIFTS SLIGHTLY
SOUTH THROUGH THIS AFTERNOON AND COMBINES WITH ENHANCED
CONVERGENCE ALONG SEA BREEZE BOUNDARY AS IT ADVANCES INLAND AND
OTHER LOCALIZED BOUNDARIES. WITH ALL THIS BEING SAID...THERE IS
NOT MUCH IN THE WAY OF UPPER LEVEL SUPPORT AS WE REMAIN ON THE TOP
OF RIDGE ALOFT. THE SW FLOW FROM THE SFC THROUGH THE LOW LEVEL
FLOW WILL VEER TO BECOME MORE WESTERLY WHICH WILL AID IN DOWNSLOPE
FLOW AND HEATING...SOME DRYING AND WILL ALSO HELP TO KEEP SEA
BREEZE PINNED CLOSER TO THE COAST INITIALLY. AS HEATING INCREASES
EXPECT CU AND SHWRS/TSTMS TO FORM ALONG CONVERGENT BOUNDARIES. SPC
HAS KEPT OUR AREA IN A MARGINAL RISK FOR SVR STORMS AS A
MODERATELY UNSTABLE AIR MASS YIELDS STRONG UPDRAFT/DOWNDRAFT
GROWTH WITH POTENTIAL FOR ISOLATED DAMAGING WINDS. THE HRRR SHOWS
MAIN FOCUS ALONG WEAKENING FRONT FROM MARLBORO TO PENDER COUNTIES
BY 18Z AND OTHER MORE ISOLATED CONVECTIVE DEVELOPMENT ALONG SEA
BREEZE FROM GEORGETOWN COUNTY UP THROUGH THE GRAND STRAND INTO THE
CAPE FEAR AREA. THE STEERING FLOW WILL BE OUT OF THE NW WHICH WILL
PUSH ALL STORMS SOUTHEAST AND TOWARD THE COAST WITH OTHER STORMS
DEVELOPING ALONG COLLIDING BOUNDARIES.
MOST OF THIS ACTIVITY WILL END THIS EVENING AS CONVECTION WILL BE
ALMOST EXCLUSIVELY DIURNALLY FORCED. MIN TEMPS TONIGHT WILL AGAIN
BE QUITE WARM...DROPPING ONLY TO AROUND 80 AT THE BEACHES...75
WELL INLAND.
&&
.SHORT TERM /THURSDAY THROUGH FRIDAY NIGHT/...
AS OF 3 AM WEDNESDAY...LONG LIVED MID LEVEL RIDGE WILL START SHOWING
SIGNS OF WEAKENING DURING THE PERIOD ALTHOUGH THE HEAT AND HUMIDITY
WILL CONTINUE. RIDGE HOLDS ON THU BUT STARTS TO BREAK DOWN LATER FRI
AS 5H TROUGH APPROACHES FROM THE NORTHWEST. AT THE SURFACE THE
BERMUDA HIGH AND PIEDMONT TROUGH REMAIN IN PLACE ALONG WITH DAILY
DEVELOPMENT OF THE AFTERNOON SEA BREEZE. DEEP MOISTURE REMAINS IN
PLACE WITH PRECIPITABLE WATER VALUES RUNNING BETWEEN 1.75 AND 2
INCHES. MID LEVEL LAPSE RATES ARE STEEP ENOUGH FOR DEVELOPMENT OF
MODERATE TO STRONG UPDRAFTS WITH ONLY A SHALLOW LAYER OF LESS
FAVORABLE LAPSE RATES TO OVERCOME. THE PROBLEM IS THE HEIGHT OF THIS
SHALLOW STABLE LAYER WHICH IS BASED BETWEEN 7K AND 8K FT. THIS MAY
BE TOO HIGH FOR THE SEA BREEZE AND PIEDMONT TROUGH TO OVERCOME ON
THEIR OWN. ATMOSPHERE MAY REQUIRE SOME BOUNDARY INTERACTION...WITH
LEFT OVER CONVECTIVE BOUNDARIES...AND HEATING BEFORE DEEPER
CONVECTION IS ABLE TO DEVELOP. WILL CARRY CHC POP EACH AFTERNOON BUT
FAVOR A LATER TIMING GIVEN THE AFOREMENTIONED LIMITATIONS.
TEMPERATURES WILL CONTINUE TO RUN WELL ABOVE CLIMO WITH HIGHS IN THE
MID 90S AND LOWS IN THE MID TO UPPER 70S.
&&
.LONG TERM /SATURDAY THROUGH TUESDAY/...
AS OF 3 AM WEDNESDAY...MID LEVEL TROUGH AND STALLED SURFACE BOUNDARY
WILL RESULT IN UNSETTLED WEATHER FOR MUCH OF THE PERIOD. LARGE 5H
TROUGH SETS UP OVER THE EASTERN CONUS BUT THE TROUGHS AXIS WILL
REMAIN WEST OF THE AREA THROUGH TUE. COMBINATION OF DIURNAL
HEATING...DEEP AND MOIST SOUTHWEST FLOW...AND AN OCCASIONAL
SHORTWAVE ROTATING AROUND THE BASE OF THE TROUGH WILL LEAD TO AN
INCREASE IN SHOWER AND THUNDERSTORM ACTIVITY ACROSS THE AREA. BEST
CHANCES WILL BE SAT INTO SUN AS THE TROUGH ARRIVES AND PUSHES A COLD
FRONT INTO THE AREA. DEEP MOISTURE PRESENT AHEAD OF THE TROUGH ALONG
WITH SHORTWAVE ENERGY WARRANTS AT LEAST HIGH CHC TO LIKELY POP SAT.
MOISTURE LINGERS THROUGH THE FIRST HALF OF SUN BUT LOW LEVEL
INSTABILITY DECREASES. WILL HOLD ONTO PRECIP CHANCES SUN AND SUN
NIGHT BUT TREND POP DOWNWARD...ESPECIALLY SUN NIGHT.
MID LEVEL DRY AIR WORKS IN FOR LATE SUN THROUGH TUE AS A LOBE OF THE
5H TROUGH EJECTS NORTHEAST...WITH WEAK SUBSIDENCE OVER THE
SOUTHEAST. LONGWAVE TROUGH AXIS REMAINS WEST OF THE AREA AND THE
DISSIPATING FRONT WILL REMAIN STALLED OVER OR JUST EAST OF THE AREA.
THE LACK OF MID LEVEL MOISTURE WILL HINDER DEEPER CONVECTION BUT
STILL EXPECT AT LEAST SOME DEVELOPMENT. PLAN TO MAINTAIN INHERITED
SILENT POP MON AND TUE GIVEN AN UNFAVORABLE ENVIRONMENT AND A FAIR
AMOUNT OF UNCERTAINTY.
HIGH TEMPERATURES WILL BE NEAR TO SLIGHTLY BELOW CLIMO DUE TO THE
INCREASED MOISTURE/CLOUD COVER ALONG WITH THE POTENTIAL FOR MORE
CONVECTION. LOWS WILL CONTINUE TO RUN ABOVE CLIMO.
&&
.AVIATION /12Z WEDNESDAY THROUGH SUNDAY/...
AS OF 12Z...TERMINALS ARE VFR THIS MORNING AND VFR WILL LIKELY
CONTINUE THROUGH 18Z. WINDS WILL BE SW-W 5-10 KTS EXCEPT BECOMING
SSW AT THE COASTAL TERMINALS MID MORNING ON.
THUNDERSTORMS RESULTING IN TEMPO REDUCED FLIGHT CONDITIONS AND GUSTY
WINDS WILL BE THE BIGGEST THREATS TO AVIATION MAINLY THIS AFTERNOON
AND EVENING. THUNDERSTORMS SHOULD DEVELOP AFTER 17Z INITIALLY ALONG
A WEAK FRONT NEAR KLBT TO N OF KILM. DRY AIR IN THE MID LEVELS
SHOULD ALLOW FOR LESS ACTIVITY TO DEVELOP ELSEWHERE. SOME BOUNDARIES
COULD THROWN OFF TO THE SOUTH ALLOWING THUNDERSTORMS TO DEVELOP
FURTHER S IN THE AFTERNOON AND EVENING. CONFIDENCE OF THUNDERSTORM
OCCURRENCE IS HIGHEST N.
ACTIVITY DISSIPATES DURING THE EVENING. WINDS MAY BE VARIABLE IN THE
EVENING/EARLY MORNING WHERE STORMS HAVE OCCURRED...BUT GENERALLY
LIGHT SW WINDS CAN BE EXPECTED OVERNIGHT WITH VFR CONDITIONS.
EXTENDED OUTLOOK...ISOLATED SHOWERS AND STORMS THURSDAY. MODERATE
CONFIDENCE FOR SCATTERED TO NUMEROUS SHOWERS AND STORMS FRIDAY
AFTERNOON THROUGH SUNDAY WITH MVFR/IFR CONDITIONS AND POSSIBLE HEAVY
RAIN.
&&
.MARINE...
NEAR TERM /THROUGH TONIGHT/...
AS OF 1000 AM WEDNESDAY...A SCEC REMAINS IN EFFECT UNTIL NOON AS
MODERATE SW WINDS CONTINUED. CONDITIONS WILL IMPROVE AS WINDS
DIMINISH.
WINDS AND SEAS WILL EASE THIS AFTN AS THE LLJ WEAKENS AND THE
OVERALL GRADIENT RELAXES A BIT. WINDS WILL REMAIN FROM THE SW
THROUGH TODAY...BUT FALL TO AROUND 15 KTS...AND SEAS WILL DROP IN
TANDEM TO 3-4 FT WITH THE SW WIND CHOP DOMINATING THE SPECTRUM.
SHORT TERM /THURSDAY THROUGH FRIDAY NIGHT/...
AS OF 3 AM WEDNESDAY...BERMUDA HIGH AND PIEDMONT TROUGH COMBO
WILL MAINTAIN SOUTHWEST FLOW ACROSS THE WATERS THROUGH THE PERIOD.
GRADIENT WILL INCREASE THU INTO FRI WITH SOLID 20 KT DEVELOPING
THU NIGHT AND CONTINUING THROUGH THE END OF THE PERIOD. SEAS 3 TO
4 FT AT THE START OF THE PERIOD WILL BUILD TO 3 TO 5 FT AND
POSSIBLY 4 TO 6 FT FRI AND FRI NIGHT. HEADLINES MAY BE REQUIRED
FOR THE SECOND HALF OF THE PERIOD.
LONG TERM /SATURDAY THROUGH SUNDAY/...
AS OF 3 AM WEDNESDAY...BERMUDA HIGH COMBINED WITH LOW PRESSURE
ROTATING THROUGH THE MID ATLANTIC AND THE APPROACH OF THE
ASSOCIATED COLD FRONT WILL PINCH THE SURFACE GRADIENT SAT INTO
SUN. SOUTHWEST FLOW WILL REMAIN 15 TO 20 KT THOUGH THE PERIOD.
FRONT IS NOT EXPECTED TO MOVE OVER THE WATERS BUT INSTEAD REMAIN
STALLED INLAND. THIS WILL KEEP WINDS OUT OF THE SOUTHWEST THROUGH
SUN. SEAS WILL RUN 3 TO 5 FT BUT GIVEN THE EXTENDED PERIOD OF
WINDS AROUND 20 KT CANNOT RULE OUT SOME 6 FT SEAS...ESPECIALLY
WATERS NEAR 20 NM OPEN TO SOUTHWEST FETCH AND HEADLINES COULD BE
REQUIRED FOR AT LEAST A PORTION OF THE PERIOD.
&&
.ILM WATCHES/WARNINGS/ADVISORIES...
SC...HEAT ADVISORY UNTIL 8 PM EDT THIS EVENING FOR SCZ017-023-024-
032-033-039-053>056.
NC...HEAT ADVISORY UNTIL 8 PM EDT THIS EVENING FOR NCZ087-096-099-
105>110.
MARINE...NONE.
&&
$$
NEAR TERM...RGZ
SHORT TERM...III
LONG TERM...III
AVIATION...MRR
AREA FORECAST DISCUSSION
NWS BISMARCK ND
956 AM CDT WED JUN 24 2015
.UPDATE...
ISSUED AT 940 AM CDT WED JUN 24 2015
THE LATEST RADAR INDICATES CONVECTION IS MOVING FASTER THAN A
CONSENSUS OF THE LAST THREE HRRR RUNS. PRECIPITATION CHANCES WERE
UPDATED TO DO A BETTER JOB OF INDICATING THE MOST LIKELY TIMES FOR
PRECIPITATION AS A MID LEVEL SHORTWAVE RACES ACROSS THE STATE
TODAY. ANOTHER ROUND OF SHOWERS AND THUNDERSTORMS WILL COMMENCE AS
THE NEXT IN A LONG TRAIN OF SHORTWAVES MOVES FROM WESTERN MONTANA
INTO THE DAKOTAS AFTER MIDNIGHT TONIGHT...SO THAT WILL BE THE
SHORT TERM FOCUS FOR LATER FORECAST UPDATES.
UPDATE ISSUED AT 618 AM CDT WED JUN 24 2015
APPROACHING SHORT WAVE IS BRINGING SCATTERED SHOWERS/THUNDERSTORMS
ACROSS EASTERN MONTANA NUDGING INTO NORTHWEST NORTH DAKOTA. HAVE
ADJUSTED POPS A BIT TO ACCOUNT FOR THIS. HAVE ALSO ADJUSTED CLOUD
COVER WITH THE APPROACHING STORMS AND TO ACCOUNT FOR CLOUDS STREAMING
OFF THE ONGOING CONVECTION OVER SOUTHWEST/SOUTH CENTRAL SOUTH
DAKOTA.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 333 AM CDT WED JUN 24 2015
THUNDERSTORMS ONCE AGAIN HIGHLIGHT THE SHORT TERM.
WITH PERSISTENT ZONAL FLOW AND UPPER LEVEL JET PARKED OVER THE
REGION...AND LEE CYCLOGENESIS...DIURNAL THUNDERSTORMS WILL
CONTINUE TO BE POSSIBLE. SHORT TERM MODELS INDICATE THUNDERSTORM
DEVELOPMENT ACROSS EASTERN MONTANA AND WESTERN NORTH DAKOTA LATE
THIS MORNING INTO THE EARLY AFTERNOON HOURS...SPREADING ACROSS
CENTRAL NORTH DAKOTA LATE IN THE AFTERNOON AND EVENING HOURS. A
MOIST AND UNSTABLE BOUNDARY LAYER REMAINS ACROSS THE NORTHERN
PLAINS. WITH SOUTHERLY FLOW AT THE SURFACE AND STRONG WESTERLIES
ALOFT...SHEAR WILL CONTINUE TO BE VERY STRONG. SPC HAS NORTH
DAKOTA IN A MARGINAL RISK FOR SEVERE STORMS TODAY. WITH PERSISTENT
CAPE GREATER THAN 1K J/KG AND SHEAR GREATER THAN 50 KNOTS...ANY
STORMS THAT DO FORM COULD QUICKLY BECOME SUPERCELLULAR WITH THE
THREAT FOR DAMAGING WIND AND HAIL.
.LONG TERM...(THURSDAY THROUGH TUESDAY)
ISSUED AT 333 AM CDT WED JUN 24 2015
HIGHLIGHT IN THE LONG TERM WILL BE DIMINISHING THUNDERSTORM
CHANCES GOING INTO THE WEEKEND ALONG WITH A WARMING TREND.
WEST/NORTHWEST FLOW CONTINUES ON THURSDAY WHILE UPPER RIDGE OVER
THE WESTERN CONUS STARTS TO GRADUALLY INTENSIFY. VARIETY OF WEAK
DISTURBANCES CONTINUE TO MOVE THROUGH THE FLOW BRINGING
THUNDERSTORM CHANCES. MODEST SHEAR/INSTABILITY OVER MOST OF THE
AREA WILL KEEP SEVERE THREAT ON THE LOW SIDE...THOUGH OVER THE
SOUTHWEST 0-6 KM BULK SHEAR WILL APPROACH 40KTS WITH CAPE VALUES
~1-1.5 KJ/KG WILL BRING A MARGINAL SEVERE THREAT.
FOR FRIDAY RIDGE CONTINUES TO AMPLIFY WITH UPPER FLOW SHIFTING
MORE NORTHWESTERLY...THOUGH A FEW WEAK WAVES MOVING THROUGH MAY
BRING A FEW THUNDERSTORMS TO THE AREA.
FOR THE WEEKEND...RIDGE CONTINUES TO AMPLIFY. THIS WILL BRING DRY
CONDITIONS OVER OUR WEST...WITH POSSIBLY A FEW STORMS TOWARDS THE
EAST AS A FEW WEAK WAVES MOVE THROUGH. TEMPERATURES WILL WARM TO
ABOVE AVERAGE.
WARM TEMPERATURES CONTINUE INTO EARLY NEXT WEEK WITH OCCASIONAL
LOW THUNDERSTORMS CHANCES AS A FEW WEAK WAVES MOVE THROUGH
NORTHWESTERLY UPPER LEVEL FLOW.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z THURSDAY MORNING)
ISSUED AT 618 AM CDT WED JUN 24 2015
ISOLD/SCT TSRA EXPECTED THROUGH TODAY INTO TONIGHT ACROSS WESTERN
AND CENTRAL NORTH DAKOTA. OTHERWISE...VFR CONDITIONS WILL PREVAIL.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...SCHECK
SHORT TERM...AJ
LONG TERM...JJS
AVIATION...AJ
AREA FORECAST DISCUSSION
NWS GREENVILLE-SPARTANBURG SC
707 AM EDT WED JUN 24 2015
.SYNOPSIS...
STRONG MID LEVEL HIGH PRESSURE WILL PERSIST ACROSS THE REGION
THROUGH THE REMAINDER OF THE WORK WEEK...MAINTAINING WELL ABOVE
NORMAL TEMPERATURES. A BROAD UPPER LEVEL TROF WILL MOVE OVER THE
REGION OVER THE WEEKEND RETURNING TEMPERATURES TO SEASONAL LEVELS BY
SUNDAY AND INCREASING CHANCES FOR WIDESPREAD SHOWERS AND
THUNDERSTORMS. A COOLER AND DRIER PATTERN WILL TAKE SHAPE AFTER A
FRONT PASSES EARLY IN THE WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 700 AM EDT...DEBRIS CLOUDS HAVE KEPT ANY MORNING VALLEY FOG TO
A MINIMUM. OTHERWISE...THE WEAK SURFACE FRONTAL BOUNDARY IS FORECAST
TO STALL OVER THE FORECAST AREA TODAY AND THEN GRADUALLY LIFT
NORTHWARD AS A WARM FRONT TONIGHT. THE HRRR CONTINUES TO TREND
TOWARD BETTER TSTM COVERAGE IN SRN SECTIONS THIS AFTN...SOUTH OF THE
BOUNDARY. MODEL PROFILES REMAIN FAIRLY WARM ALOFT...HOWEVER...SEVERE
WEATHER WILL BE A THREAT WITH ANY TSTMS THAT FORM AS MODERATE OR
BETTER CAPE LOOKS LIKELY ALONG WITH MID LEVEL DRY AIR AND ASSOCIATED
THETA E LAPSES YIELDING SOME MEASURE OF MICROBURST POTENTIAL. THE
SRN HALF WILL BE MOST AT RISK GIVEN THE BOUNDARY LOCATION AND LIKELY
SBCAPE VALUES OF 3000 TO 3500 J/KG THERE DURING PEAK HEATING.
TEMPERATURES AND ASSOCIATED HEAT INDEX VALUES WILL BE THE OTHER
ISSUE FOR THE FORECAST TODAY. BL AND 850 TEMPS LOOK COMPARABLE TO
YESTERDAY...BUT SO DOES THE POTENTIAL FOR SOME DEWPOINT MIXING IN
THE WARMEST PIEDMONT SECTIONS. PLUS...THERE COULD BE DEBRIS CLOUDS
AROUND AT TIMES TODAY. WILL KEEP HEAT INDEX VALUES IN THE SRN
PIEDMONT AT 100 TO 104 THIS AFTN. ANTICIPATE ANOTHER VERY MILD NIGHT
WITH PRECIPITATION CHANCES STEADILY WANING WITH THE LOSS OF HEATING.
&&
.SHORT TERM /THURSDAY THROUGH FRIDAY/...
AS OF 245 AM WEDNESDAY...ON THURSDAY...THE H5 AND H7 RIDGE WILL
REMAIN CENTERED OVER THE DEEP SOUTH. HOWEVER...HEIGHTS SHOULD RISE
FROM THE SOUTH AS THE RIDGE CENTER DRIFTS EAST DURING THE DAY. USING
A BLEND OF PREFERRED GUIDANCE...I WILL FORECAST HIGHS AROUND 90
WITHIN THE MTN VALLEYS TO MID TO HIGH 90S ACROSS THE FOOTHILLS AND
PIEDMONT. A WEST TO EAST FRONT WILL REMAIN ACROSS THE OHIO RIVER
VALLEYS AS A SFC TROF COVERS THE FOOTHILLS AND PIEDMONT. GIVEN THE
SFC PATTERN...LLVL WINDS ARE FORECAST TO REMAIN LIGHT FROM THE WSW.
FORECAST SOUNDINGS REVEAL THAT A SIGNIFICANT LAYER OF CIN WILL
REMAIN AROUND H75...VALUES RANGING FROM 40-60 J/KG. THE LACK OF
FORCING AND LINGERING CAPPING SHOULD FAVOR LITTLE TO NO COVERAGE OF
DEEP CONVECTION ON THURSDAY. I WILL FORECAST DRY CONDITIONS EAST OF
THE MTNS...WITH SCHC OVER THE RIDGES.
ON FRIDAY...SHORT RANGE MODELS INDICATE THAT A WEAK MID LEVEL LOW
WILL LINGER NEAR THE GA/FL LINE DURING THE DAY. IN ADDITION...A
POSITIVE TILTED L/W TROF WILL BEGIN TO AMPLIFY ACROSS THE MID
WEST...SLIDING EAST. AT THE SFC...A BROAD AREA OF LOW PRESSURE IS
EXPECTED TO DEVELOP ACROSS THE CAROLINAS AS A SFC FRONT STALLS OVER
THE REGION. FORECAST SOUNDINGS INDICATE THAT MOISTURE WILL SURGE
ACROSS THE REGION...WITH PW VALUES OVER 2 INCHES BY THE AFTERNOON.
THE MOISTURE COMBINED WITH WELL ABOVE AVERAGE HIGH TEMPERATURES
SHOULD YIELD WIDESPREAD MODERATE VALUES OF CAPE. GIVEN THE BROAD
AREA OF LLVL MOISTURE CONVERGENCE...INSTABILITY...AND INCREASING MID
LEVEL FORCING...TSRA COVERAGE WILL INCREASE SIGNIFICANTLY FROM
THURSDAY. I WILL FORECAST LIKELY POPS ACROSS THE MTNS WITH VALUES IN
THE 40 TO 50 RANGE EAST.
&&
.LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/...
AS OF 3 AM WEDNESDAY...SIGNIFICANT PATTERN CHANGE WILL SETTLE OVER
THE REGION THIS WEEKEND AND SHOULD REMAIN THROUGH THE EXTENDED
PERIOD. MODELS INDICATE THAT THE AXIS OF A L/W TROUGH WILL SWEEP
ACROSS THE REGION THIS WEEKEND...WITH A SECONDARY WAVE EXPECTED TO
CROSS THE APPALACHIANS ON TUESDAY. AT THE SFC...THE CENTER OF A
DEEPENING LOW WILL MOVE FROM THE OHIO RIVER VALLEY ON SATURDAY TO
SOUTHERN NY BY SUNDAY EVENING. A COLD FRONT SHOULD PUSH ACROSS THE
REGION LATE SATURDAY AFTERNOON AND EVENING. THE ENVIRONMENT AHEAD OF
THE FRONT WILL FEATURE WIDESPREAD INSTABILITY AND WEAK
SHEAR...POSSIBLY SUPPORTING A BAND OF TSRA SAT AFTERNOON. I WILL
FORECAST CATE COVERAGE NEAR THE TN LINE...WITH GENERALLY LIKELY POPS
ACROSS THE REST OF THE CWA. DRIER AIR WILL BUILD ACROSS THE REGION
ON SUNDAY...RESULTING IN FALLING POP VALUES. I WILL FORECAST
PRIMARILY DIURNAL POPS ACROSS THE REGION MON AND TUES. TEMPERATURES
THROUGH THE EXTENDED ARE FORECAST TO RANGE FROM BELOW NORMAL THIS
WEEKEND TO NEAR NORMAL BY TUESDAY.
&&
.AVIATION /11Z WEDNESDAY THROUGH SUNDAY/...
AT KCLT...A WEAK FRONT SAGGING SOUTH ACROSS THE TERMINAL AREA THIS
MORNING WILL TOGGLE SURFACE WINDS TO NE LATE MORNING THROUGH THE
AFTN. PRECIPITATION CHANCES LOOK RATHER SMALL AROUND THE AIRFIELD
GIVEN THE WARM PROFILES ALOFT...BUT ANY CONVECTION THAT FORMS WILL
BE STRONG. VFR CONDITIONS WILL CONTINUE WITH HIGH BASED CUMULUS
FORMING AND BEING TOPPED BY TEMPO HIGH CLOUD DEBRIS CIGS FROM TIME
TO TIME.
ELSEWHERE...CONVECTIVE CHANCES REMAIN GREATEST AT KAVL THIS AFTN DUE
TO TERRAIN FLOW AND LOW LEVEL CONVERGENCE...BUT A TSRA CANNOT BE
RULED OUT ACROSS THE UPSTATE SITES WHERE INSTABILITY WILL BE THE
GREATEST. ANY TSRA WOULD BE QUITE STRONG WITH THE POTENTIAL FOR
GUSTY WINDS GIVEN THE MID LEVEL DRY AIR. EXPECT SFC WINDS TO TOGGLE
NW THEN NE THROUGH THE DAY BEFORE TURNING AROUND THE DIAL TO SE
LATE. THE BEST CHANCE FOR RESTRICTIONS EARLY THU MORNING WILL BE IN
THE MTN VALLEYS...BUT WILL CONFINE THE FOG TO MVFR AT KAVL FOR NOW.
OUTLOOK...SCT DIURNAL TSTM CHANCES WILL INCREASE LATE WEEK INTO THE
WEEKEND AS A COLD FRONT EVENTUALLY APPROACHES FROM THE NW. MORNING
RESTRICTIONS DUE TO FOG AND/OR STRATUS ARE POSSIBLE...PARTICULARLY
WHERE HEAVY RAIN FELL THE PREVIOUS DAY...AND IN THE MOUNTAIN RIVER
VALLEYS.
CONFIDENCE TABLE...
11-17Z 17-23Z 23-05Z 05-06Z
KCLT HIGH 100% HIGH 100% HIGH 100% HIGH 100%
KGSP HIGH 100% HIGH 100% HIGH 100% HIGH 100%
KAVL HIGH 94% HIGH 100% HIGH 100% HIGH 100%
KHKY HIGH 100% HIGH 100% HIGH 100% HIGH 100%
KGMU HIGH 100% HIGH 100% HIGH 100% HIGH 100%
KAND HIGH 100% HIGH 100% HIGH 100% HIGH 100%
THE PERCENTAGE REFLECTS THE NUMBER OF GUIDANCE MEMBERS AGREEING
WITH THE SCHEDULED TAF ISSUANCE FLIGHT RULE CATEGORY. COMPLETE HOURLY
EXPERIMENTAL AVIATION FORECAST CONSISTENCY TABLES AND ENSEMBLE FORECASTS
ARE AVAILABLE AT THE FOLLOWING LINK: (MUST BE LOWER CASE)
WWW.WEATHER.GOV/GSP/AVIATION_TABLES
&&
.CLIMATE...
RECORD MAXIMUM TEMPERATURES FOR THIS WEEK...WITH YEARS IN WHICH THE
VALUES WERE LAST REACHED.
WEDNESDAY JUNE 24...
AVL 94 1952
CLT 102 1930
GSP 100 1952
THURSDAY JUNE 25...
AVL 96 1952
CLT 102 1914
GSP 101 1952
&&
.GSP WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
NC...NONE.
SC...NONE.
&&
$$
SYNOPSIS...NED
NEAR TERM...HG
SHORT TERM...NED
LONG TERM...NED
AVIATION...HG
CLIMATE...
AREA FORECAST DISCUSSION
NWS LITTLE ROCK AR
227 PM CDT WED JUN 24 2015
.SHORT TERM...TONIGHT THROUGH SATURDAY NIGHT
QUITE A BIT OF CLOUDS HAVE BEEN POPPING UP AROUND THE STATE TODAY
WITH TEMPS AND DEW POINTS FAIRLY SIMILAR TO WHAT WAS SEEN YESTERDAY.
HAVE ALREADY BEGAN TO SEE A FEW SHOWERS AND THUNDERSTORMS FIRE ALONG
THE MISSISSIPPI RIVER...AND THEREFORE HAVE ADDED POPS TO MUCH OF THE
EASTERN PORTIONS OF THE CWA. BOTH HRRR AND WRF AGREE POP UP SHOWERS
AND THUNDERSTORMS WILL BE POSSIBLE IN EASTERN ARKNASAS...HOWEVER DO
BELIEVE THE BETTER CHANCES FOR PRECIPITATION WILL REMAIN EAST OF THE
RIVER AND THUS JUST HAVE SLIGHT CHANCE POPS AT THIS TIME.
SIMILAR CONDITIONS WILL BE EXPECTED ON THURSDAY WITH CHANCES FOR
DIURNALLY DRIVEN PRECIPITATION ACROSS SOUTHERN AND EASTERN ARKANSAS.
CONDITIONS WILL ONCE AGAIN BE HOT AND HUMID ON THURSDAY...SO A HEAT
ADVISORY WILL ONCE AGAIN BE IN EFFECT.
ATTENTION THEN SHIFTS TO FRIDAY AS THE UPPER LEVEL RIDGE RETROGRADES
TO THE WEST AND NW FLOW ALOFT DRIVES A COLD FRONT INTO THE STATE
LATE FRIDAY AND INTO SATURDAY. SHOWERS AND THUNDERSTORMS WILL
DEVELOP AHEAD OF THE FRONT FRIDAY AFTERNOON AND EVENING...RESULTING
IN CHANCES FOR STRONG TO SEVERE THUNDERSTORMS. THE MAIN THREATS WITH
THESE STORMS WOULD BE DAMAGING WINDS.
DO BELIEVE THE COLD FRONT WILL CLEAR THE STATE BY MID DAY ON
SATURDAY WHICH IS A LITTLE EARLIER THAN PREVIOUSLY ADVERTISED. AS A
RESULT...DID BEGIN TO TREND POPS DOWN SATURDAY MORNING AND REMOVE
THEM SATURDAY AFTERNOON. THIS SETS THE STAGE FOR COOLER AND DRY AIR
IN THE FORECAST FOR THE LONG TERM.
&&
.LONG TERM...SUNDAY THROUGH THURSDAY
UPPER AIR PATTERNS ACROSS NORTH AMERICA WILL BE WELL AMPLIFIED AT
THE START OF THIS PERIOD...WITH A 2 SIGMA RIDGE CENTERED OVER THE
NORTHERN ROCKIES...AND A 2 SIGMA TROUGH CENTERED OVER THE OHIO
VALLEY. WELL BELOW NORMAL TEMPERATURES ARE EXPECTED A THE START OF
THE PERIOD...WITH A SLOW WARMING TREND EXPECTED THEREAFTER...AS
THE PATTERN DEAMPLIFIES.
&&
.PRELIMINARY POINT TEMPS/POPS...
BATESVILLE AR 74 95 74 90 / 20 20 30 60
CAMDEN AR 73 96 75 92 / 20 20 10 40
HARRISON AR 71 93 71 85 / 10 10 30 60
HOT SPRINGS AR 74 97 75 92 / 20 10 10 50
LITTLE ROCK AR 76 96 76 93 / 20 10 20 50
MONTICELLO AR 76 96 75 93 / 20 20 20 40
MOUNT IDA AR 70 95 73 91 / 10 10 10 50
MOUNTAIN HOME AR 71 95 71 86 / 10 20 30 60
NEWPORT AR 74 96 74 90 / 20 20 30 60
PINE BLUFF AR 75 96 74 92 / 20 20 20 50
RUSSELLVILLE AR 72 96 73 92 / 10 10 20 60
SEARCY AR 73 95 74 92 / 20 10 20 60
STUTTGART AR 76 96 75 92 / 20 20 20 50
&&
.LZK WATCHES/WARNINGS/ADVISORIES...
HEAT ADVISORY UNTIL 6 PM CDT THIS EVENING FOR ARKANSAS-BRADLEY-
CALHOUN-CLEBURNE-CLEVELAND-DALLAS-DESHA-DREW-FAULKNER-GRANT-
INDEPENDENCE-JACKSON-JEFFERSON-LINCOLN-LONOKE-MONROE-PRAIRIE-
PULASKI-SALINE-WHITE-WOODRUFF.
HEAT ADVISORY FROM 1 PM TO 6 PM CDT THURSDAY FOR ARKANSAS-
BRADLEY-CALHOUN-CLEBURNE-CLEVELAND-DALLAS-DESHA-DREW-FAULKNER-
GRANT-INDEPENDENCE-JACKSON-JEFFERSON-LINCOLN-LONOKE-MONROE-
PRAIRIE-PULASKI-SALINE-WHITE-WOODRUFF.
&&
$$
SHORT TERM...65 / LONG TERM...55
AREA FORECAST DISCUSSION
NWS JACKSONVILLE FL
250 PM EDT WED JUN 24 2015
...ISOLD STRONG TO SEVERE STORMS REST OF TODAY...
.SHORT TERM...SO FAR TODAY ONLY ISOLD TO SCT CONVECTION OVER NE FL
SLOWLY MOVING ENEWD. WITH SBCAPE VALUES OF 2000-3000J...HIGH
CONFIDENCE CONVECTION WILL FURTHER INCREASE AND PROPAGATE SLOWLY EWD
GIVEN THE PREVAILING SWLY TO WLY FLOW AT ABOUT 5-10 MPH THROUGH
ABOUT 12 KFT. WET DOWNBURSTS ARE THE PRIMARY THREAT WITH GUSTS OF 50-
60 MPH POSSIBLE. HAVE PAINTED POPS OF 40-60 PERCENT IN NE FL AND 20-
40 PERCENT IN SE GA. FOR TONIGHT...ISOLD TO SCT CONVECTION WILL BE
ONGOING IN THE EVENING WITH BEST COVERAGE IN NE FL. EXPECT
CONVECTION TO WIND DOWN LATER TODAY THOUGH SOME ISOLD CELLS...MAINLY
SHOWERS WILL BE POSSIBLE WELL AFTER MIDNIGHT. MIN TEMPS IN THE LOWER
TO MID 70S EXPECTED.
THURSDAY...LOW LEVEL TROUGH REMAINS ENTRENCHED FROM THE CAROLINAS
SWWD TO CENTRAL AL AND MS. BEST MOISTURE POSITIONED AGAIN OVER NE FL
AND PORTIONS OF SE GA WITH GFS SOUNDING SHOW PWAT OF 2 INCHES.
GUIDANCE INDICATING AN ACTIVE DAY...MORE THAN TODAY. FOR NOW SHOWED
SOLID 60 PERCENT FOR NE FL AND 40-60 IN SE GA. PRIMARY THREATS
REMAIN FREQUENT LIGHTNING AND STRONG DOWNBURST WINDS WITH PULSE
STORMS GIVEN WEAK BULK SHEAR VALUES. HIGHS WILL BE A BIT LOWER THAN
THE PAST FEW DAYS...PREVAILING IN THE LOWER 90S.
UPPER PATTERN TRANSITIONS THURSDAY NIGHT THRU FRIDAY NIGHT FROM
UPPER RIDGE SOUTHERN STATES...ZONAL WESTERLIES NORTHERN STATES...TO
A PATTERN FEATURING A STRONG WESTERN UPR RIDGE...STRONG E-CTRL UPR
TROF BY SAT MORNING. WILL CONTINUE PATTERN OF CHANCE POPS FOR
AFTERNOON/EVENING SHOWERS/T-STORMS THRU FRIDAY EVENING. SLIGHTLY
LOWER HIGH TEMPS EXPECTED FRIDAY WITH LWR 90S INTERIOR...AROUND 90
EASTERN COUNTIES..UPR 80S COAST. LOW TEMPS LWR-MID 70S INLAND...MID-
UPR 70S COAST THURSDAY AND FRIDAY NIGHTS.
.LONG TERM /SATURDAY THRU WEDNESDAY/...
WEEKEND FEATURES STRONG UPR TROF OVER EASTERN STATES WITH SURFACE
COLD FRONT DRIFTING SE OVER SRN GA. ANTICIPATE A DECENT FRONTAL BAND
OF SHOWERS/ FEW T-STORMS OVER SRN GA SAT AFTN/NIGHT...AND ACROSS
ENTIRE FORECAST AREA SUNDAY. TEMPTED TO GO LIKELY POPS THESE
AREAS...BUT CAPPED AT 50 PCT FOR THE MOMENT...LATER SHIFTS MAY
INCREASE POPS FURTHER AS CERTAINTY ON THAT LEVEL OF COVERAGE
INCREASES. HIGH TEMPS SAT AROUND 90 COAST AND SCTRL GA... LWR 90S
ELSEWHERE. FOR SUNDAY...SLIGHTLY LOWER...WITH UPR 80S SRN GA AND
COAST...AROUND 90 INLAND NE FL.
UPPER PATTERN CHANGES VERY LITTLE THROUGH THE MIDDLE OF NEXT WEEK.
FRONTAL MOISTURE BAND SITS OVER NRN FL...WITH DECENT CHANCE POPS
EACH DAY ACROSS NE FL...LESSER CHANCES ACRS SE GA. CONSENSUS MODEL
GUIDANCE SUGGESTS SOME TEMPS EXPECTED TO BE CLOSE TO NORMAL EARLY
NEXT WEEK.
&&
.AVIATION...A FEW TSTMS CAN BE EXPECTED IN AND NEAR THE NE FL TAFS
REST OF TODAY WITH MVFR AND GUSTY WINDS. TEMPO GROUPS ADVERTISED
GENERALLY FROM 19Z-23Z...BUT THESE MAY NEED TO BE EXTENDED FURTHER
INTO THE EVENING BASED ON LATEST HRRR GUIDANCE. HOWEVER...ANTICIPATE
CONVECTION WILL BE ON A DOWNWARD TREND AFTER 01Z/02Z WITH VFR
PREVAILING THEREAFTER.
&&
.MARINE....SURFACE TROUGH REMAINS OVER SC INTO CTRL GA...WHILE
SURFACE HIGH PRESSURE IS CENTERED WELL EAST OF THE WATERS...SETTING
UP A S TO SW FLOW PATTERN OVER THE WATERS DURING THE REMAINDER OF
THE WEEK. NOCTURNAL SW FLOW SURGES MAY LEAD TO WINDS CLOSE TO
EXERCISE CAUTION LEVELS IN THE OFFSHORE COMPONENT EACH NIGHT.
A COLD FRONT APPROACHES FROM THE NW DURING THE WEEKEND...WHICH COULD
ENHANCE SW FLOW OVER THE WATERS THEN.
RIP CURRENTS: LOW RISK THROUGH THURSDAY.
&&
.PRELIMINARY POINT TEMPS/POPS...
AMG 74 95 74 91 / 30 50 40 50
SSI 77 91 77 88 / 20 40 30 50
JAX 74 92 74 90 / 40 60 40 50
SGJ 75 89 75 89 / 50 60 40 50
GNV 73 91 73 90 / 50 60 40 50
OCF 74 91 73 90 / 40 60 40 50
&&
.JAX WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
GA...NONE.
AM...NONE.
&&
$$
SHASHY/WOLF/WALSH
AREA FORECAST DISCUSSION
NWS CHARLESTON SC
401 PM EDT WED JUN 24 2015
.SYNOPSIS...
ATLANTIC HIGH PRESSURE WILL PREVAIL MUCH OF THIS WEEK WHILE A TROUGH
OF LOW PRESSURE PERSISTS INLAND. A COLD FRONT WILL STALL TO THE
NORTH LATE WEEK INTO THE WEEKEND BEFORE FINALLY CROSSING THE AREA
SUNDAY. THE FRONT COULD STALL JUST OFFSHORE BEFORE DISSIPATING EARLY
NEXT WEEK.
&&
.NEAR TERM /UNTIL 6 AM THURSDAY MORNING/...
THROUGH THIS EVENING...SATELLITE PICTURES INDICATE THAT WE/RE
FINALLY STARTING TO SEE SOME VERTICAL DEVELOPMENT TO THE CUMULUS
CLOUD FIELD...FEEDING OFF THE STEEPENING LAPSE RATES. THERE ARE
VARIOUS MESO-SCALE BOUNDARIES SUCH AS OUTFLOW FROM EARLIER MCS/S AND
THE EVER PRESENT PIEDMONT TROUGH. BUT THEY`RE OUTSIDE THE CWFA...SO
WE NEED TO FOCUS INITIALLY IN OUR AREA ON THE SEA BREEZE INLAND
FROM US-17 AND A FEW POPCORN TYPE CELLS THAT FORM DURING THE MAX
HEATING OF THE DAY. BUT DUE TO THE WARM MID LEVELS THEY STILL
MIGHT HAVE SOME DIFFICULTY IN REACHING ANY APPRECIABLE VERTICAL
GROWTH. HOWEVER THERE IS AN ABUNDANCE OF INSTABILITY...WITH
SBCAPES ARE 4000-5000 J/KG AND LIFTED INDICES AS COLD AS -6 TO
-8C. SO IF BOUNDARY MERGERS GET GOING WE WOULD CERTAINLY SEE AN
INCREASE IN BOTH COVERAGE AND UPDRAFT STRENGTH TO THE CONVECTION.
WITH DCAPES OF 1000-1200 J/KG AND WINDEX VALUES OF 65 KT THIS
WOULD SUPPORT STRONG DOWNBURST WINDS...AIDED BY PRECIP LOADING
WITH PWATS CLOSE TO THE 90TH PERCENTILE FOR LATE JUNE. OTHER
HAZARDS INCLUDE FREQUENT LIGHTNING STRIKES...VERY HEAVY RAINS DUE
TO A STORM MOTION OF ONLY AROUND 5 MPH AND SHOULD ANY TALL STORMS
DEVELOP THERE IS ALSO HAIL RISK. PROBABILITY OF SEVERE WEATHER IS
STILL TOO LOW TO INCLUDE IN THE HAZARDOUS WEATHER OUTLOOK...MOST
NOTABLY DUE TO THE HRRR SHOWING LITTLE IN THE WAY OF SIGNIFICANT
CONVECTIVE DEVELOPMENT/ORGANIZATION. WE/LL MAINTAIN A FORECAST OF
ISOLATED TO SCATTERED COVERAGE...ESPECIALLY INLAND...ALTHOUGH ANY
LOW-END SEVERE POTENTIAL LOOKS TO BE FROM ABOUT 6-9 PM. STORMS
WILL GRADUALLY DWINDLE IN BOTH INTENSITY AND AREAL SCOPE...COMING
TO AN END ENTIRELY 11 PM-MIDNIGHT.
THE HEAT ADVISORY HAS WORKED PERFECTLY WITH MANY SITES HAVING HIT
105-110F...WITH EVEN A FEW LOCATIONS SUCH AS WITHERBEE...GOOSE CREEK
AND SYLVANIA REACHING 111-114F. PROVIDED SHOWERS AND T-STORMS DON/T
ORGANIZE TOO MUCH TO IMPACT THE TEMP CURVE...THE HEAT ADVISORY WILL
CONTINUE THROUGH 7 PM.
FOR THE REST OF TONIGHT...THERE ARE HINTS THAT CONVECTION MIGHT GO
OVERNIGHT...BUT ODDS FAVOR THAT ANY ACTIVITY AFTER MIDNIGHT WOULD
IMPACT THE WATERS OUT NEAR THE GULF STREAM AS NOCTURNAL CINH
INCREASES. CONVECTIVE DEBRIS CLOUDINESS WILL DWINDLE AND
FADE...LEAVING US WITH MOSTLY CLEAR OR PARTLY CLOUDY SKIES. A WARM
SW SYNOPTIC FLOW AND MUCH OF THE AREA NEVER FULLY DECOUPLING WILL
PREVENT TEMPS FROM DROPPING ANY LOWER THAN 73-78 INLAND AND 79-82
ON THE COAST AND IN DOWNTOWN CHARLESTON.
&&
.SHORT TERM /6 AM THURSDAY MORNING THROUGH SATURDAY/...
THURSDAY...A LARGE MID LVL RIDGE OF HIGH PRESSURE WILL PERSIST OVER
THE AREA. AT THE SFC...THE AREA WILL BE POSITIONED ALONG THE WESTERN
PERIPHERY OF ATLANTIC HIGH PRESSURE WHILE A PIEDMONT TROUGH BECOMES
SLIGHTLY MORE PRONOUNCED WITH A LOW PRESSURE SYSTEM TRACKING OVER
THE MID ATLANTIC STATES. DESPITE LARGE SCALE SINKING MOTION
ASSOCIATED WITH HIGH PRESSURE ALOFT...THE PROXIMITY OF THE LOW
PRESSURE TROUGH INLAND AND A STALLING COLD FRONT TO OUR NORTH SHOULD
SUPPORT A SLIGHT CHANCE TO LOW-END CHANCE OF SHOWERS AND
THUNDERSTORMS DURING AFTERNOON/EVENING HOURS. DCAPES IN EXCESS OF
1000 J/KG SUGGEST DAMAGING WIND GUST POTENTIAL WITH A FEW STRONGER
THUNDERSTORMS THAT DEVELOP. HOWEVER...THE THREAT OF WIDESPREAD
SEVERE WEATHER IS NOT EXPECTED.
THE MAIN CONCERN ON THURSDAY WILL BE HEAT/HUMIDITY LEVELS...WHICH
WILL BE DEPENDENT ON HOW MUCH CONVECTIVE ACTIVITY OCCURS BEFORE
TYPICAL PEAK HEATING HOURS. AT THIS TIME...HIGH TEMPS ARE FORECAST
TO REACH THE MID/UPPER 90S...WARMEST INLAND. HOWEVER...STRONG
HEATING SHOULD MIX OUT SFC DEWPTS TO AROUND 70 INLAND...WHILE DEWPTS
REMAIN IN THE MID 70S NEAR/BEHIND AN INLAND MOVING SEABREEZE. THESE
TEMPS AND MOISTURE LEVELS SHOULD SUPPORT HEAT INDEX VALUES NEAR 105
DEGREES FOR A FEW HOURS THURSDAY AFTERNOON AND A HEAT ADVISORY COULD
EVENTUALLY BE NEEDED. HOWEVER...SHOULD CLOUD COVER OR PRECIP SHIFT
OVER THE AREA EARLY...HEAT INDEX VALUES WILL LIKELY FALL JUST SHORT
OF ADVISORY LEVELS. OVERNIGHT LOWS WILL REMAIN MILD...IN THE
MID/UPPER 70S INLAND TO LOWER 80S ALONG THE COAST.
FRIDAY AND SATURDAY...MODELS INDICATE LOWERING 500 MB HEIGHTS OVER
THE AREA THIS WEEKEND AS THE MID LVL RIDGE OF HIGH PRESSURE WEAKENS
IN RESPONSE TO A TROUGH OF LOW PRESSURE DIGGING OVER THE
MIDWEST/GREAT LAKES REGION. MOISTURE LEVELS ARE EXPECTED TO INCREASE
AHEAD OF THE APPROACHING TROUGH...WITH PWATS PROJECTED TO BE NEAR
2.0 INCHES OVER THE SOUTHEASTERN UNITED STATES. THESE MOISTURE
LEVELS ALONG WITH INCREASED FORCING FROM A SFC LOW THAT DEVELOPS
ALONG A STALLED FRONT TO OUR NORTH...WILL LIKELY RESULT IN AT LEAST
CHANCES OF SHOWERS/THUNDERSTORMS ON FRIDAY. BY SATURDAY...GREATER
FORCING AND SHEAR WILL LIKELY ARRIVE AS STRONGER WIND FIELDS ROUND
THE SOUTHERN PERIPHERY OF THE MID/UPPER LOW CENTERED OVER THE GREAT
LAKES REGION. SHOWERS AND THUNDERSTORMS WILL LIKELY OCCUR SATURDAY
AFTERNOON...WITH SOME STRONGER THUNDERSTORMS POSSIBLE AHEAD OF A SFC
COLD FRONT MAKING WAY INTO THE SOUTHEASTERN UNITED STATES. DAMAGING
WIND GUSTS APPEAR TO BE THE MAIN THREAT WITH STRONGER THUNDERSTORMS
ON SATURDAY. GIVEN THE AMPLE MOISTURE...SOME THUNDERSTORMS COULD
ALSO PRODUCE HEAVY RAINFALL.
TEMPS ARE EXPECTED TO BE SLIGHTLY COOLER OVER THE WEEKEND...WITH MAX
TEMPS IN THE LOW/MID 90S ON FRIDAY...THEN LOW 90S ON SATURDAY DUE TO
AN INCREASE IN CONVECTIVE COVERAGE. GIVEN THE COOLING TREND...HEAT
ADVISORIES WILL LIKELY NO LONGER BE NEEDED THIS WEEKEND. OVERNIGHT
LOWS SHOULD REMAIN IN THE MID/UPPER 70S.&&
.LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/...
BROAD UPPER TROUGH WILL ENCOMPASS THE EASTERN U.S. THROUGH THE LONG
TERM PERIOD. A POTENT SHORTWAVE WILL SEND AN AREA OF LOW PRESSURE
AND ATTENDANT FRONT THROUGH THE FORECAST AREA ON SUNDAY. GIVEN
FORCING FROM UPPER JET...SHORTWAVE ENERGY AND COLD FRONT...IT SHOULD
BE A PRETTY ACTIVE DAY ESPECIALLY GIVEN DECENT SHEAR AND DEEP
MOISTURE. THE FRONT WILL LIKELY PUSH OFF THE COAST EARLY
MONDAY...AND REMAIN STATIONARY OFFSHORE BEFORE DISSIPATING TUESDAY.
WEAK HIGH PRESSURE IS EXPECTED TO PREVAIL BY MID WEEK. TEMPERATURES
WILL BE AT OR BELOW CLIMO THROUGH THE PERIOD.
&&
.AVIATION /20Z WEDNESDAY THROUGH MONDAY/...
VFR THROUGH 18Z THURSDAY.
ISOLATED SHRA/TSRA WILL CONTINUE TO DEVELOP IN THE VICINITY OF
KCHS THROUGH 01Z...AND WE WILL AMEND AS NECESSARY SHOULD ANYTHING
LOOK TO MORE DIRECTLY AFFECT THE AIRFIELD.
WHILE WE CAN/T RULE OUT A TSRA IMPACTING KSAV FROM ABOUT
21-01Z...PROBABILITIES ARE STILL TOO LOW TO INCLUDE WITH THE
LATEST TAF SET.
EXTENDED AVIATION OUTLOOK...FLIGHT RESTRICTIONS ARE POSSIBLE IN
AFTERNOON SHOWERS/THUNDERSTORMS...ESPECIALLY LATE THIS WEEKEND.
&&
.MARINE...
TONIGHT...IT/S STATUS QUO IN REGARDS TO THE SYNOPTIC PATTERN AND
RESULTING CONDITIONS ACROSS THE COASTAL WATERS...WITH SUB-TROPICAL
RIDGING TO THE SOUTH/SE...MESO-HIGH PRESSURE IN THE NE GULF OF
MEXICO AND A NE-SW ALIGNED TROUGH INLAND. ADEQUATE MIXING OF 20-25
KT GEOSTROPHIC WINDS AND A MODEST GRADIENT WILL ALLOW FOR SOUTH/SW
WINDS UP TO 15 OR 20 KT WITH OCCASIONAL HIGHER GUSTS. WAVES OF 1-2
FT WILL BE COMMON IN CHARLESTON HARBOR...WITH 2-4 FT IN THE OPEN
ATLANTIC...HIGHEST ON AMZ350-374.
THURSDAY THROUGH MONDAY...ATLANTIC HIGH PRESSURE WILL DOMINATE THE
COASTAL WATERS WHILE A TROUGH OF LOW PRESSURE PERSISTS INLAND
THROUGH LATE WEEK. A COLD FRONT IS EXPECTED TO SHIFT OVER THE WATERS
LATE WEEKEND...BEFORE EVENTUALLY STALLING/DISSIPATING EARLY NEXT
WEEK. A TIGHTENED PRESSURE GRADIENT WILL KEEP WINDS FAIRLY ELEVATED
THROUGH THE PERIOD. NOCTURNAL JETTING AND AFTERNOON SEA BREEZE
CIRCULATIONS WILL RESULT IN SOUTH/SOUTHWEST WINDS PEAKING AROUND 15-
20 KTS AT TIMES...ESPECIALLY ACROSS THE CHARLESTON COUNTY COASTAL
WATERS. WIND GUSTS COULD REACH SMALL CRAFT ADVISORY CRITERIA
SATURDAY AFTERNOON OR NIGHT...THEN SLOWLY IMPROVE EARLY NEXT WEE,
SEAS WILL MAINLY BE 2-4 FEET...BUT COULD REACH 6 FEET IN THE OUTER
PORTIONS OF THE WATERS THIS WEEKEND.
&&
.CLIMATE...
RECORD HIGH MINIMUMS FOR JUNE 24TH...
KCHS...79 SET IN 1998.
KCXM...85 SET IN 1998.
KSAV...80 SET IN 1914.
RECORD HIGH MINIMUMS FOR JUNE 25TH...
KCHS...79 SET IN 2010.
KCXM...83 SET IN 1998.
KSAV...80 SET IN 1914.
&&
.CHS WATCHES/WARNINGS/ADVISORIES...
GA...HEAT ADVISORY UNTIL 7 PM EDT THIS EVENING FOR GAZ087-088-
099>101-114>119-137>141.
SC...HEAT ADVISORY UNTIL 7 PM EDT THIS EVENING FOR SCZ040-042>045-
047>052.
MARINE...NONE.
&&
$$
SYNOPSIS...
NEAR TERM...
SHORT TERM...
LONG TERM...
AVIATION...
MARINE...
CLIMATE...
AREA FORECAST DISCUSSION
NWS CHARLESTON SC
138 PM EDT WED JUN 24 2015
.SYNOPSIS...
ATLANTIC HIGH PRESSURE WILL PREVAIL MUCH OF THIS WEEK WHILE A TROUGH
OF LOW PRESSURE PERSISTS INLAND. A COLD FRONT WILL STALL TO THE NORTH
LATE WEEK INTO THE WEEKEND BEFORE FINALLY CROSSING THE AREA LATE
SUNDAY. THE FRONT MAY STALL JUST OFFSHORE BEFORE DISSIPATING EARLY
NEXT WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
FOR THE AFTERNOON UPDATE WE HAVE MADE MINOR CHANGES TO HOURLY/MAX
TEMPS...POPS AND SKY COVER...BUT NOTHING MAJOR. CONVECTION HAS
BEEN SLOW IN DEVELOPING...WITH ONLY FEW-SCATTERED CUMULUS
FORMATION. WE/LL SOON HIT OUR CONVECTIVE TEMP IN THE MID 90S...SO
THE GENERAL TREND OF THE FORECAST IS STILL ON TRACK.
AFTER OUR BRIEF RESPITE FROM THE EXTREME HEAT AND HUMIDITY
COMBINATION YESTERDAY...IT/S BACK TO THE OPPRESSIVE AND STICKY
CONDITIONS THAT WE HAVE SEEN MUCH OF THE PAST 2 WEEKS. TEMPS ARE
RUNNING ON AVERAGE ABOUT 2-3F WARMER THAN 24 HOURS AGO...AND WITH
850 MB TEMPS OF 19-20C AND PLENTY OF INSOLATION...WE/RE ON OUR WAY
TO THE MID AND UPPER 90S INLAND FROM US-17. A FEW SPOTS MIGHT EVEN
PEAK AT THE CENTURY MARK. DEW POINTS WILL MIX OUT A BIT
INLAND...BUT WILL POOL BEHIND THE SEA BREEZE...WHICH SUPPORTS MOST
HEAT INDICES AS HIGH AS 105-109F...BUT A FEW SPOTS OF THE COASTAL
CORRIDOR WILL MAX OUT AT 110-114F AROUND THE TIME OF THE SEA
BREEZE PASSAGE. OUR HEAT ADVISORY WILL OBVIOUSLY REMAIN ACTIVE.
THE FORECAST FOR HOW CONVECTION WILL PAN OUT IS FAR FROM CERTAIN
GIVEN A WIDE DISPARITY IN VARIOUS MODELS. WE STILL HAVE A SUBTLE
WEAKNESS IN THE RIDGING ALOFT...BUT THAT LOOKS TO BE JUST OFF THE
COAST. THERE WILL BE VARIOUS MESO-SCALE BOUNDARIES SUCH AS
OUTFLOW FROM EARLIER MCS THAT MOVED OFF THE MID-ATLANTIC AND
ANOTHER FROM ALABAMA. THERE IS ALSO THE EVER PRESENT PIEDMONT
TROUGH AND THE SEA BREEZE BOUNDARY. THESE FACTORS SHOULD PROVIDE
THE NECESSARY INITIATION...BUT THERE IS STILL A STRONG 3-5C CAP
AND UNFAVORABLE MID LEVEL LAPSE RATES WITH WARM 500 MB
TEMPS...IMPLYING THAT STORMS MAY HAVE A DIFFICULT TIME IN
ATTAINING MUCH VERTICAL GROWTH. ON THE FAVORABLE SIDE OUR LOW
LEVEL LAPSE RATES ARE FAVORABLE AND THERE IS PLENTY OF INSTABILITY
WITH SBCAPES FORECAST TO REACH 4000-4500 J/KG AND LIFTED INDEX OF
-6 TO -8C. LOOK FOR CONVECTION TO GET GOING AROUND 3-4 PM AS WE
HIT OUR CONVECTIVE TEMP IN THE MID 90S.
FOR THE MOMENT A PULSE TYPE ENVIRONMENT SEEMS A MORE LIKELY
CONVECTIVE MODE RATHER THAN MULTI-CELLULAR...BUT IF BOUNDARY
INTERACTIONS AND MERGERS TAKE PLACE THAT COULD CHANGE. WE/LL
MAINTAIN A PROBABILITY FORECAST OF 20-30 PERCENT...HIGHEST INLAND
AND MAINTAIN A CLOSE WATCH ON MESO-SCALE TRENDS TO SEE IF WE NEED
TO RAISE POPS.
DCAPES OF 1000-1200 J/KG AND WINDEX VALUES OF 65 KT WOULD SUPPORT
STRONG DOWNBURST WINDS...AIDED BY PRECIP LOADING WITH PWATS CLOSE
TO THE 90TH PERCENTILE FOR LATE JUNE. OTHER HAZARDS INCLUDE
FREQUENT LIGHTNING STRIKES...VERY HEAVY RAINS DUE TO A STORM
MOTION OF ONLY AROUND 5 MPH AND SHOULD ANY TALL STORMS DEVELOP
THERE IS ALSO HAIL RISK. PROBABILITY OF SEVERE WEATHER IS STILL
TOO LOW TO INCLUDE IN THE HAZARDOUS WEATHER OUTLOOK...MOST NOTABLY
DUE TO THE HRRR SHOWING LITTLE IN THE WAY OF CONVECTIVE
ORGANIZATION.
CONDITIONS SHOULD BE MAINLY QUIET TONIGHT WITH PARTLY CLOUDY SKIES
AND LOWS A BIT WARMER THAN WEDNESDAY MORNING...ESPECIALLY IF TSTMS
COVERAGE IS LOWER END TODAY.
&&
.SHORT TERM /THURSDAY THROUGH SATURDAY/...
THURSDAY...PERSISTENT MID LEVEL RIDGE WILL HOLD FAIRLY STRONG FOR
ONE MORE DAY...ALTHOUGH SUBTLE WEAKENING WILL BEGIN TO OCCUR. THE
SURFACE PATTERN WILL CONTINUE TO BE FAIRLY STATIC AS THE AREA
REMAINS ON THE WESTERN PERIPHERY OF ATLANTIC HIGH PRESSURE WITH A
PIEDMONT TROUGH SITUATED INLAND. HIGH TEMPERATURES IN THE MID/UPPER
90S AWAY FROM THE COAST WILL COMBINE WITH MODERATE HUMIDITY LEVELS
TO PRODUCE HEAT INDICES OF 105-108 IN THE AFTERNOON. THUS A HEAT
ADVISORY WILL LIKELY BE NEEDED. LARGE SCALE FORCING WILL LARGELY BE
MISSING HOWEVER CONVECTION WILL DEVELOP AS A RESULT OF SEA BREEZE
AND/OR CONVERGENCE ALONG SURFACE TROUGH. FORECAST SURFACE BASED
CAPE NEAR 3000 J/KG MAY SUPPORT A FEW STRONGER POSSIBLY SEVERE
STORMS...WITH GUSTY WINDS THE PRIMARY THREAT GIVEN DCAPE VALUES IN
EXCESS OF 1000 J/KG. THURSDAY NIGHT...SURFACE LOW PRESSURE WILL
CROSS THE MID-ATLANTIC STATES ABSORBING THE PIEDMONT TROUGH. AN
ATTENDANT FRONT WILL STALL NORTH OF THE AREA. LOWS WILL BE QUITE
MILD RANGING FROM THE MID 70S INLAND TO AROUND 80 ALONG THE COAST.
FRIDAY...AN AREA OF LOW PRESSURE WILL DEVELOP OVER THE CAROLINAS
ALONG THE AFOREMENTIONED STALLED FRONT. DEEP MOISTURE AND PROXIMITY
TO BOUNDARY WILL ALLOW FOR HIGHER COVERAGE OF SHOWERS AND
THUNDERSTORMS. FORECAST CURRENTLY FEATURES HIGH CHANCE POPS OVER
MUCH OF THE AREA DURING PEAK HEATING HOURS. A FEW STRONGER STORMS
WILL BE POSSIBLE ESPECIALLY IN THE NORTHERN ZONES WHERE INSTABILITY
AND MID LEVEL ENVIRONMENT IS MORE FAVORABLE...WITH GUSTY WINDS
PRIMARY THREAT. FORECAST HEAT INDICES MAY BRIEFLY REACH THE LOCAL
HEAT ADVISORY CRITERIA OF 105 IN THE AFTERNOON WITH HIGH
TEMPERATURES IN THE LOW/MID 90S...HOWEVER DURATION AND AREAL EXTENT
WILL BE MARGINAL AT BEST AND GIVEN EXPECTED CONVECTION...THINK A
HEAT ADVISORY WILL LIKELY NOT BE NEEDED. CONVECTION MAY LINGER INTO
THE OVERNIGHT PERIOD...WITH FOCUS SHIFTING MORE TO THE COASTAL
WATERS. LOWS WILL AGAIN BE IN THE MID TO UPPER 70S.
SATURDAY...THE UPPER LEVEL PATTERN WILL BECOME MUCH MORE AMPLIFIED
AS DEEPENING TROUGH AND ASSOCIATED VORT MAX DIGS INTO THE GREAT
LAKES REGION. THIS WILL HELP SEND ANOTHER AREA OF LOW PRESSURE
TOWARDS EAST COAST WHICH WILL EVENTUALLY ENGULF THE STATIONARY
FRONT/LOW. BETTER UPPER SUPPORT...DEEP MOISTURE AND VARIOUS SURFACE
BOUNDARIES WILL ALLOW FOR A FAIRLY ACTIVE DAY WITH STRONGER STORMS
POSSIBLE GIVEN DECENT SHEAR AND FORECAST INSTABILITY. HIGH
TEMPERATURES WILL MAINLY BE IN THE LOW 90S.
&&
.LONG TERM /SATURDAY NIGHT THROUGH TUESDAY/...
BROAD UPPER TROUGH WILL ENCOMPASS THE EASTERN U.S. THROUGH THE LONG
TERM PERIOD. A POTENT SHORTWAVE WILL SEND AN AREA OF LOW PRESSURE
AND ATTENDANT FRONT THROUGH THE FORECAST AREA ON SUNDAY. GIVEN
FORCING FROM UPPER JET...SHORTWAVE ENERGY AND COLD FRONT...IT SHOULD
BE A PRETTY ACTIVE DAY ESPECIALLY GIVEN DECENT SHEAR AND DEEP
MOISTURE. THE FRONT WILL LIKELY PUSH OFF THE COAST EARLY
MONDAY...AND REMAIN STATIONARY OFFSHORE BEFORE DISSIPATING TUESDAY.
WEAK HIGH PRESSURE IS EXPECTED TO PREVAIL BY MID WEEK. TEMPERATURES
WILL BE AT OR BELOW CLIMO THROUGH THE PERIOD.
&&
.AVIATION /18Z WEDNESDAY THROUGH MONDAY/...
VFR THROUGH 18Z THURSDAY. WHILE WE CAN/T RULE OUT A TSRA IMPACTING
EITHER TERMINAL FROM ABOUT 20Z-01Z...PROBABILITIES ARE STILL TOO
LOW TO INCLUDE WITH THE LATEST TAF SET.
EXTENDED AVIATION OUTLOOK...BRIEF FLIGHT RESTRICTIONS POSSIBLE IN
AFTERNOON SHOWERS/THUNDERSTORMS...ESPECIALLY THIS WEEKEND.
&&
.MARINE...
THE COASTAL WATERS SYNOPTIC PATTERN IS NOT CHANGING MUCH AND
MARINERS FAMILIAR WITH THE SUMMER PATTERNS WILL NOT GET ANY BIG
SURPRISES THROUGH TONIGHT. SOUTH/SW SEA BREEZE CIRCULATIONS THIS
AFTERNOON AND SW NOCTURNAL SURGES WILL PUSH SPEEDS INTO THE 15-20
KT RANGE WITH SOME HIGHER GUSTS AT FAVORED AREAS SUCH AS THE
CHARLESTON LAND/SEA INTERFACE. SEAS WILL BE 2-4 FT ON
AVERAGE...HIGHEST WELL OFFSHORE. WAVES IN THE HARBOR WILL BE 1 TO
2 FT THROUGH THIS EVENING.
THURSDAY THROUGH MONDAY...ATLANTIC HIGH PRESSURE WILL PREVAIL OVER
THE COASTAL WATERS WHILE A TROUGH OF LOW PRESSURE PERSISTS INLAND
THROUGH THE REMAINDER OF THE WEEK. A COLD FRONT IS EXPECTED TO
APPROACH THE WATERS OVER THE WEEKEND AND EVENTUALLY STALL AND
DISSIPATE EARLY NEXT WEEK. TIGHTENED PRESSURE GRADIENT WILL KEEP
WINDS FAIRLY ELEVATED THROUGH THE PERIOD. NOCTURNAL JETTING AND
AFTERNOON SEA BREEZE CIRCULATIONS WILL RESULT IN SOUTH/SOUTHWEST
WINDS PEAKING AROUND 15-20 KT...ESPECIALLY ACROSS THE CHARLESTON
COUNTY COASTAL WATERS. GUSTS MAY REACH NEAR SMALL CRAFT ADVISORY
CRITERIA OF 25 KT AT TIMES...AND HEADLINES MAY NEED TO BE
CONSIDERED. SEAS WILL MAINLY BE 2-4 FEET...BUT MAY REACH 5-6 FEET IN
THE OUTER PORTIONS OF THE WATERS DURING SURGES.
&&
.CLIMATE...
RECORD HIGH MINIMUMS FOR JUNE 24TH...
KCHS...79 SET IN 1998.
KCXM...85 SET IN 1998.
KSAV...80 SET IN 1914.
RECORD HIGH MINIMUMS FOR JUNE 25TH...
KCHS...79 SET IN 2010.
KCXM...83 SET IN 1998.
KSAV...80 SET IN 1914.
&&
.CHS WATCHES/WARNINGS/ADVISORIES...
GA...HEAT ADVISORY UNTIL 7 PM EDT THIS EVENING FOR GAZ087-088-
099>101-114>119-137>141.
SC...HEAT ADVISORY UNTIL 7 PM EDT THIS EVENING FOR SCZ040-042>045-
047>052.
MARINE...NONE.
&&
$$
SYNOPSIS...
NEAR TERM...
SHORT TERM...ECT
LONG TERM...ECT
AVIATION...
MARINE...
CLIMATE...
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
517 PM CDT WED JUN 24 2015
.SHORT TERM...
317 PM CDT
THROUGH SATURDAY...
WILL BE PUSHING BACK THE START TIME OF THE FLASH FLOOD WATCH OVER
EASTERN SECTIONS OF THE AREA TILL AROUND 06 UTC THIS
EVENING...OTHERWISE NO CHANGES TO THE WATCH PLANNED.
THE EARLY MORNING SHOWERS AND THUNDERSTORMS OVER WEST CENTRAL
ILLINOIS PUSHED AN OUTFLOW BOUNDARY SOUTHWARD OVER MISSOURI...AND
THIS HAS EFFECTIVELY PUSHED THE SURFACE WARM FRONT AND BETTER
INSTABILITY FARTHER SOUTH OVER MISSOURI. AS SUCH...I HAVE SOME
CONCERNS THAT THE HEAVY RAIN AND SEVERE THREAT...AT LEAST INITIALLY
THIS EVENING MAY BE DELAYED AND FOCUSED OVER WESTERN PORTIONS OF
ILLINOIS AND IOWA. THE HRRR RUNS HAVE BEEN PICKING UP ON THIS
POSSIBILITY OVER THE PAST COUPLE HOURS...AND WITH THE SURFACE
BOUNDARY STILL OVER CENTRAL AND WESTERN SECTIONS OF MISSOURI...I AM
THINKING IT MAY BE HEADING IN THE RIGHT DIRECTION. WITH THIS IN MIND
I DID CUT BACK ON POPS THIS EVENING OVER EASTERN SECTIONS OF THE
REGION AND HAVE PUSHED THE FLASH FLOOD WATCH OFF UNTIL 05 UTC FOR
THE CHICAGO METRO AREA AND NORTHWESTERN INDIANA.
THE CONVECTIVE ACTIVITY OVER IOWA IS ASSOCIATED WITH AN MCV...AND
THIS MAY MOVE OVER PORTIONS OF NORTHERN ILLINOIS LATE THIS
AFTERNOON AND EARLY THIS EVENING. HOWEVER...IT APPEARS WITH THE
INSTABILITY GRADIENT REMAINING TO OUR SOUTHWEST...THUNDERSTORMS WILL
LIKELY BECOME MORE SCATTERED WITH THE EASTWARD EXTENT OF THIS
PRECIPITATION. THEREFORE...ONLY A FEW LINGERING SHOWERS AND PERHAPS
A FEW THUNDERSTORMS MAY MOVE OVER THE AREA THROUGH EARLY THIS
EVENING.
THUNDERSTORMS WILL STILL LIKELY BEGIN TO DEVELOP UPSTREAM OVER
EASTERN IOWA AND INTO WESTERN ILLINOIS THROUGH THE EVENING A
SOUTHWESTERLY LOW LEVEL JET NOSES INTO THIS AREA. THIS WILL RESULT
IN BACKBULDING AND TRAINING THUNDERSTORMS WITH HEAVY RAINFALL.
HOWEVER...IT APPEARS THE MAIN FOCUS FOR THIS ACTIVITY MAY REMAIN JUST
WEST OF MY AREA...AT LEAST FOR MUCH OF THE EVENING. WITH TIME...IT
APPEARS THE FOCUS MAY BEGIN TO SHIFT EASTWARD INTO NORTHEASTERN
ILLINOIS AND NORTHWESTERN INDIANA...BUT THIS MAY NOT BE UNTIL AFTER
MIDNIGHT TONIGHT. HEAVY RAIN RATES WILL STILL BE A CONCERN...AND IT
APPEARS THE HEAVIEST RAIN MAY FALL SOUTH OF INTERSTATE 88.
THE HEAVY RAIN THREAT WILL CONTINUE INTO THE LATE MORNING/EARLY
AFTERNOON ON THURSDAY...ESPECIALLY SOUTH OF I-80 AS THE SURFACE
SYSTEM MOVES OVER THE AREA. HOWEVER...ONCE THE SURFACE LOW PASSES
EAST...THE FRONTAL BOUNDARY WILL SHIFT SOUTH OF THE AREA LATER IN
THE DAY...BRINGING THE SHOWER AND STORM THREAT TO AN END.
AS FOR THE SEVERE THREAT...IT APPEARS THIS TOO MAY END UP BEING
FARTHER SOUTH THAN PREVIOUSLY THOUGHT. ALTHOUGH UNCERTAINTY REMAINS
AS TO HOW THE SEVERE THREAT WILL EVOLVE TONIGHT. IT APPEARS AT THIS
POINT THAT THE HIGHEST THREAT MAY END UP BEING PRIMARILY SOUTH OF
INTERSTATE 80...AND BE MAINLY A DAMAGING WIND THREAT.
MUCH COOLER WEATHER WILL BUILD IN OVER MUCH OF THE REGION IN THE
WAKE OF THIS FRONT. ANOTHER SYSTEM LOOKS TO DEVELOP AND IMPACT THE
OHIO VALLEY REGION LATER FRIDAY INTO EARLY SATURDAY AS AN UPPER
TROUGH DIGS OVER THE LOWER GREAT LAKES REGION. IT APPEARS MOST OF THE
PRECIP WITH THIS SYSTEM WILL REMAIN SOUTH OF MOST OF MY AREA. COOL
CONDITIONS WILL BE THE RULE FOR A FEW DAYS...WITH A BREAK IN THE
WEATHER...FINALLY.
KJB
&&
.LONG TERM...
346 AM CDT
ADVERTISED UPPER LEVEL PATTERN SHIFT TO A MUCH HIGHER AMPLITUDE FLOW
WILL BE IN PLACE BY SUNDAY. THIS HIGH AMPLIFIED PATTERN WILL BREAK
DOWN GRADUALLY WITH TIME THROUGH THE 4 DAY PERIOD BUT A NORTHWEST
FLOW ALOFT WILL PERSIST THROUGH WEDNESDAY. WHILE MODELS TO DEPICT A
SERIES OF UPPER LEVEL SHORTWAVES TO SLIDE ACROSS THE AREA THROUGH
THE PERIOD THE NATURE OF THE PRECIPITATION SYSTEMS THESE FEATURES
WILL PRODUCE WILL BE MUCH DIFFERENT COMPARED TO THE PAST 3 WEEKS.
DESPITE MENTION OF POPS EACH DAY THERE WILL BE LONG DRY SPELLS IN
BETWEEN AND ANY RAIN THAT DOES FALL WILL BE GENERALLY BRIEF AND
RELATIVELY LIGHT. THE BETTER WINDOWS FOR RAINFALL APPEAR TO BE
DIURNALLY ENHANCED DURING THE AFTERNOONS MONDAY AND TUESDAY AND
ASSOCIATED WITH A PAIR OF WEAK SECONDARY COLD FRONTS BEING DRIVEN
SOUTH VIA UPPER LEVEL IMPULSES. TEMPERATURES WILL REMAIN BELOW
AVERAGE THROUGH THE PERIOD WITH LAKE BREEZES EXPECTED SUNDAY AND
WEDNESDAY... AND POSSIBLY LATE TUESDAY AS WELL.
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 22Z...
* AREA OF LGT-MOD RA TO MOVE ACROSS TERMINALS ROUGHLY 2330Z-0200Z.
LITTLE IN WAY OF LIGHTNING EXPECTED...THOUGH BRIEF 4-6SM VIS AND
MID/HIGH BASED MVFR CIG POSSIBLE DURING PRECIP.
* LIGHT/VARIABLE WINDS LESS THAN 10 KT INTO EARLY THIS EVENING...
THOUGH MAY FAVOR A TREND IN DIRECTION FROM SW BACKING TO SE OR E
BY EARLY EVENING.
* THUNDERSTORM POTENTIAL APPEARS TO BE DECREASING THROUGH MIDNIGHT
AS FOCUS EXPECTED TO BE FROM WEST/CENTRAL IA INTO CENTRAL IL AT
THIS TIME.
RATZER
//DISCUSSION...UPDATED 22Z...
MCV...MESOSCALE VORTICITY CENTER...CURRENTLY CENTERED JUST EAST OF
KCID/CEDAR RAPIDS IOWA AT 22Z. AREA OF LIGHT-MODERATE RAIN IN
ADVANCE OF THIS MID-LEVEL FEATURE EXTENDS INTO NORTHWEST/NORTH
CENTRAL IL AND EXTRAPOLATION OF RADAR FEATURES SUGGESTS A PERIOD
OF LIGHT-MODERATE RAIN FOR TERMINALS ALREADY BEGUN AT KRFD...WILL
ARRIVE CHI TERMINALS BETWEEN 23-00Z. LIGHTNING DETECTION NETWORK
SHOWING DECREASING TREND WITH INTRA-CLOUD DISCHARGES...AND
DECREASING INSTABILITY FARTHER EAST SUGGESTS ONLY LOW THUNDER
PROBABILITY FOR TERMINALS. TIMING OF TRAILING EDGE SUGGESTS RAIN
ENDING AROUND 01Z FOR KRFD...02Z-ISH FOR CHICAGO TERMINALS.
THUNDER THREAT LATER THIS EVENING LOOKS LATER THAN PREVIOUS
FORECAST...AND HAVE PUSHED THUNDER BACK TO AFTER MIDNIGHT.
RATZER
PREVIOUS DISCUSSION FROM 18Z...
AT THE SURFACE...A LARGE AREA OF HIGH PRESSURE IS CENTERED ALONG
THE IN/OH BORDER AS A MID LEVEL IMPULSE CROSSING THE MIDDLE
MISSISSIPPI VALLEY IS BRINGING AN AREA OF SHOWERS AND
THUNDERSTORMS FROM IOWA THROUGH CENTRAL IL TO CENTRAL IN. BASED ON
THE LATEST RADAR TRENDS...EXPECT THAT ANY PCPN AND TS SHOULD
REMAIN SOUTH OF OF THE TERMINALS EARLY THIS EVENING...THROUGH IT
COULD CLIP THE SOUTHERN PORTIONS OF THE C90 TRACON AREA. AS THE
CENTER OF THE HIGH CONTINUES TO SHIFT TO THE EAST...WINDS HAVE
BECOME SSWLY AND ARE INCREASING TO ARND 10KT. LATEST RADAR IMAGERY
AND COASTAL OBSERVATIONS SHOW A LAKE BREEZE MOVING ONSHORE NEAR
KUGN...BUT THERE IS LITTLE WESTWARD PROGRESSION AND DO NOT EXPECT
THAT THE BOUNDARY WILL REACH AS FAR WEST AS ORD/MDW.
RATHER...EXPECT THAT WINDS WILL GRADUALLY BACK TO MORE SELY
THROUGH THE AFTERNOON AND INTO THE EVENING IN RESPONSE TO THE
LARGER SCALE PRESSURE PATTERN WITH THE HIGH MOVING OFF TO THE EAST
AND LOW PRESSURE DEVELOPING OVER THE CNTRL PLAINS.
THE OTHER CONCERN FOR THE PERIOD WILL BE TIMING THE NEXT ROUND OF
THUNDERSTORMS TO IMPACT THE REGION. WHILE THE ONGOING PCPN SHOULD
REMAIN SOUTH OF THE TERMINALS...CONFIDENCE IS HIGHER THAT ANOTHER
ROUND OF THUNDERSTORMS WILL DEVELOP TONIGHT OVER THE CNTRL
PLAINS/IOWA AND THEN TRACK EASTWARD. LATEST GUIDANCE IS A LITTLE
FASTER THAN PREVIOUS MODEL RUNS AND SUGGESTS THAT TS COULD REACH
RFD BY ARND 03Z...AND THEN QUICKLY PUSHING TO THE EAST ACROSS THE
CHICAGO AREA TERMINALS. WHILE CONFIDENCE IS RELATIVELY HIGH IN TS
IMPACTING THE TERMINALS OVERNIGHT TONIGHT...TIMING AND DURATION IS
A LITTLE LOWER. ALSO...AS THE MAIN SFC LOW TRACKS ALONG A
DEVELOPING WARM FRONT EXPECTED TO SET THROUGH CNTRL OR NRN IL/IN
AND WITH UPPER LEVEL FLOW SETTING UP TO BE PARALLEL TO THE SFC
FRONT...AN EXTENDED PERIOD OF TSRA IMPACTING THE TERMINALS IS
QUITE POSSIBLE OVERNIGHT AND POSSIBLY EVEN INTO TOMORROW MORNING.
KREIN
//ORD AND MDW CONFIDENCE...UPDATED 22Z...
* MEDIUM CONFIDENCE IN WIND DIRECTION TRENDS...HIGH CONFIDENCE IN
WINDS GENERALLY LESS THAN 10 KTS THIS EVE.
* HIGH CONFIDENCE IN RA TIMING AND GENERAL LACK OF TSRA THIS
EVENING.
* LOW CONFIDENCE IN TSRA AFFECTING TERMINALS OVERNIGHT AND WITH
TIMING IF THEY DO.
RATZER
//OUTLOOK FOR ORD/MDW FOR 00Z FRIDAY-12Z WEDNESDAY...UPDATED 12Z...
THURSDAY NIGHT...VFR. WX NIL. NELY WINDS.
FRIDAY...VFR. WX NIL. NELY WINDS.
SATURDAY...VFR. WX NIL. NELY WINDS BACKING NWLY LATE.
SUNDAY...CHANCE TSRA. MVFR POSSIBLE. NWLY WINDS BACKING SWLY.
MONDAY...CHANCE TSRA. MVFR POSSIBLE. SWLY WINDS VEERING NWLY
TUESDAY...SLIGHT CHANCE TSRA. VRBL WINDS.
KREIN
&&
.MARINE...
258 PM CDT
HIGH PRESSURE RIDGING ACROSS THE SOUTHERN GREAT LAKES WILL EXIT
THE AREA TO THE EAST THIS EVENING ALLOWING LOW PRESSURE OVER THE
CENTRAL PLAINS TO MOVE NORTHEAST INTO NORTHERN ILLINOIS BY
THURSDAY MORNING. MEANWHILE A WEAK COLD FRONT ACROSS THE NORTHERN
GREAT LAKES WILL SAG SOUTH AHEAD OF HIGH PRESSURE OVER ONTARIO AND
WASH OUT AS THE AFFOREMENTIONED LOW PRESSURE AREA MOVES INTO
ILLINOIS. AS THIS LOW MOVES EAST TO OHIO THURSDAY NIGHT ITS
ASSOCIATED COLD FRONT WILL DROP SOUTH AWAY FROM THE AREA ALLOWING
ANOTHER AREA OF WEAK HIGH PRESSURE TO BUILD ACROSS THE GREAT
LAKES. THIS HIGH WILL DRIFT EAST SUNDAY NIGHT INTO MONDAY ALLOWING
A SECONDARY COLD FRONT TO SAG SOUTH ACROSS THE NORTHERN GREAT
LAKES.
ED F
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...FLASH FLOOD WATCH...ILZ003-ILZ004-ILZ008-ILZ010-ILZ011-ILZ019-
ILZ021-ILZ032-ILZ039 UNTIL 1 PM THURSDAY.
FLASH FLOOD WATCH...ILZ005-ILZ006-ILZ012-ILZ013-ILZ014-ILZ020-
ILZ022-ILZ023-ILZ033...MIDNIGHT THURSDAY TO 1 PM THURSDAY.
IN...FLASH FLOOD WATCH...INZ001-INZ002-INZ010-INZ011-
INZ019...MIDNIGHT THURSDAY TO 1 PM THURSDAY.
LM...NONE.
&&
$$
VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
WWW.FACEBOOK.COM/NWSCHICAGO
WWW.TWITTER.COM/NWSCHICAGO
WWW.YOUTUBE.COM/NWSCHICAGO
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
346 PM CDT WED JUN 24 2015
.SHORT TERM...
317 PM CDT
THROUGH SATURDAY...
WILL BE PUSHING BACK THE START TIME OF THE FLASH FLOOD WATCH OVER
EASTERN SECTIONS OF THE AREA TILL AROUND 06 UTC THIS
EVENING...OTHERWISE NO CHANGES TO THE WATCH PLANNED.
THE EARLY MORNING SHOWERS AND THUNDERSTORMS OVER WEST CENTRAL
ILLINOIS PUSHED AN OUTFLOW BOUNDARY SOUTHWARD OVER MISSOURI...AND
THIS HAS EFFECTIVELY PUSHED THE SURFACE WARM FRONT AND BETTER
INSTABILITY FARTHER SOUTH OVER MISSOURI. AS SUCH...I HAVE SOME
CONCERNS THAT THE HEAVY RAIN AND SEVERE THREAT...AT LEAST INITIALLY
THIS EVENING MAY BE DELAYED AND FOCUSED OVER WESTERN PORTIONS OF
ILLINOIS AND IOWA. THE HRRR RUNS HAVE BEEN PICKING UP ON THIS
POSSIBILITY OVER THE PAST COUPLE HOURS...AND WITH THE SURFACE
BOUNDARY STILL OVER CENTRAL AND WESTERN SECTIONS OF MISSOURI...I AM
THINKING IT MAY BE HEADING IN THE RIGHT DIRECTION. WITH THIS IN MIND
I DID CUT BACK ON POPS THIS EVENING OVER EASTERN SECTIONS OF THE
REGION AND HAVE PUSHED THE FLASH FLOOD WATCH OFF UNTIL 05 UTC FOR
THE CHICAGO METRO AREA AND NORTHWESTERN INDIANA.
THE CONVECTIVE ACTIVITY OVER IOWA IS ASSOCIATED WITH AN MCV...AND
THIS MAY MOVE OVER PORTIONS OF NORTHERN ILLINOIS LATE THIS
AFTERNOON AND EARLY THIS EVENING. HOWEVER...IT APPEARS WITH THE
INSTABILITY GRADIENT REMAINING TO OUR SOUTHWEST...THUNDERSTORMS WILL
LIKELY BECOME MORE SCATTERED WITH THE EASTWARD EXTENT OF THIS
PRECIPITATION. THEREFORE...ONLY A FEW LINGERING SHOWERS AND PERHAPS
A FEW THUNDERSTORMS MAY MOVE OVER THE AREA THROUGH EARLY THIS
EVENING.
THUNDERSTORMS WILL STILL LIKELY BEGIN TO DEVELOP UPSTREAM OVER
EASTERN IOWA AND INTO WESTERN ILLINOIS THROUGH THE EVENING A
SOUTHWESTERLY LOW LEVEL JET NOSES INTO THIS AREA. THIS WILL RESULT
IN BACKBULDING AND TRAINING THUNDERSTORMS WITH HEAVY RAINFALL.
HOWEVER...IT APPEARS THE MAIN FOCUS FOR THIS ACTIVITY MAY REMAIN JUST
WEST OF MY AREA...AT LEAST FOR MUCH OF THE EVENING. WITH TIME...IT
APPEARS THE FOCUS MAY BEGIN TO SHIFT EASTWARD INTO NORTHEASTERN
ILLINOIS AND NORTHWESTERN INDIANA...BUT THIS MAY NOT BE UNTIL AFTER
MIDNIGHT TONIGHT. HEAVY RAIN RATES WILL STILL BE A CONCERN...AND IT
APPEARS THE HEAVIEST RAIN MAY FALL SOUTH OF INTERSTATE 88.
THE HEAVY RAIN THREAT WILL CONTINUE INTO THE LATE MORNING/EARLY
AFTERNOON ON THURSDAY...ESPECIALLY SOUTH OF I-80 AS THE SURFACE
SYSTEM MOVES OVER THE AREA. HOWEVER...ONCE THE SURFACE LOW PASSES
EAST...THE FRONTAL BOUNDARY WILL SHIFT SOUTH OF THE AREA LATER IN
THE DAY...BRINGING THE SHOWER AND STORM THREAT TO AN END.
AS FOR THE SEVERE THREAT...IT APPEARS THIS TOO MAY END UP BEING
FARTHER SOUTH THAN PREVIOUSLY THOUGHT. ALTHOUGH UNCERTAINTY REMAINS
AS TO HOW THE SEVERE THREAT WILL EVOLVE TONIGHT. IT APPEARS AT THIS
POINT THAT THE HIGHEST THREAT MAY END UP BEING PRIMARILY SOUTH OF
INTERSTATE 80...AND BE MAINLY A DAMAGING WIND THREAT.
MUCH COOLER WEATHER WILL BUILD IN OVER MUCH OF THE REGION IN THE
WAKE OF THIS FRONT. ANOTHER SYSTEM LOOKS TO DEVELOP AND IMPACT THE
OHIO VALLEY REGION LATER FRIDAY INTO EARLY SATURDAY AS AN UPPER
TROUGH DIGS OVER THE LOWER GREAT LAKES REGION. IT APPEARS MOST OF THE
PRECIP WITH THIS SYSTEM WILL REMAIN SOUTH OF MOST OF MY AREA. COOL
CONDITIONS WILL BE THE RULE FOR A FEW DAYS...WITH A BREAK IN THE
WEATHER...FINALLY.
KJB
&&
.LONG TERM...
346 AM CDT
ADVERTISED UPPER LEVEL PATTERN SHIFT TO A MUCH HIGHER AMPLITUDE FLOW
WILL BE IN PLACE BY SUNDAY. THIS HIGH AMPLIFIED PATTERN WILL BREAK
DOWN GRADUALLY WITH TIME THROUGH THE 4 DAY PERIOD BUT A NORTHWEST
FLOW ALOFT WILL PERSIST THROUGH WEDNESDAY. WHILE MODELS TO DEPICT A
SERIES OF UPPER LEVEL SHORTWAVES TO SLIDE ACROSS THE AREA THROUGH
THE PERIOD THE NATURE OF THE PRECIPITATION SYSTEMS THESE FEATURES
WILL PRODUCE WILL BE MUCH DIFFERENT COMPARED TO THE PAST 3 WEEKS.
DESPITE MENTION OF POPS EACH DAY THERE WILL BE LONG DRY SPELLS IN
BETWEEN AND ANY RAIN THAT DOES FALL WILL BE GENERALLY BRIEF AND
RELATIVELY LIGHT. THE BETTER WINDOWS FOR RAINFALL APPEAR TO BE
DIURNALLY ENHANCED DURING THE AFTERNOONS MONDAY AND TUESDAY AND
ASSOCIATED WITH A PAIR OF WEAK SECONDARY COLD FRONTS BEING DRIVEN
SOUTH VIA UPPER LEVEL IMPULSES. TEMPERATURES WILL REMAIN BELOW
AVERAGE THROUGH THE PERIOD WITH LAKE BREEZES EXPECTED SUNDAY AND
WEDNESDAY... AND POSSIBLY LATE TUESDAY AS WELL.
&&
ED F
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 20Z...
* CHANCE OF LAKE BREEZE DEVELOPMENT LATE THIS AFTERNOON.
* THUNDERSTORMS LIKELY OVERNIGHT TONIGHT...MVFR-IFR CIGS/VIS
LIKELY.
KREIN
//DISCUSSION...UPDATED 18Z...
AT THE SURFACE...A LARGE AREA OF HIGH PRESSURE IS CENTERED ALONG
THE IN/OH BORDER AS A MID LEVEL IMPULSE CROSSING THE MIDDLE
MISSISSIPPI VALLEY IS BRINGING AN AREA OF SHOWERS AND
THUNDERSTORMS FROM IOWA THROUGH CENTRAL IL TO CENTRAL IN. BASED
ON THE LATEST RADAR TRENDS...EXPECT THAT ANY PCPN AND TS SHOULD
REMAIN SOUTH OF OF THE TERMINALS EARLY THIS EVENING...THROUGH IT
COULD CLIP THE SOUTHERN PORTIONS OF THE C90 TRACON AREA. AS THE
CENTER OF THE HIGH CONTINUES TO SHIFT TO THE EAST...WINDS HAVE
BECOME SSWLY AND ARE INCREASING TO ARND 10KT. LATEST RADAR IMAGERY
AND COASTAL OBSERVATIONS SHOW A LAKE BREEZE MOVING ONSHORE NEAR
KUGN...BUT THERE IS LITTLE WESTWARD PROGRESSION AND DO NOT EXPECT
THAT THE BOUNDARY WILL REACH AS FAR WEST AS ORD/MDW.
RATHER...EXPECT THAT WINDS WILL GRADUALLY BACK TO MORE SELY
THROUGH THE AFTERNOON AND INTO THE EVENING IN RESPONSE TO THE
LARGER SCALE PRESSURE PATTERN WITH THE HIGH MOVING OFF TO THE EAST
AND LOW PRESSURE DEVELOPING OVER THE CNTRL PLAINS.
THE OTHER CONCERN FOR THE PERIOD WILL BE TIMING THE NEXT ROUND OF
THUNDERSTORMS TO IMPACT THE REGION. WHILE THE ONGOING PCPN SHOULD
REMAIN SOUTH OF THE TERMINALS...CONFIDENCE IS HIGHER THAT ANOTHER
ROUND OF THUNDERSTORMS WILL DEVELOP TONIGHT OVER THE CNTRL
PLAINS/IOWA AND THEN TRACK EASTWARD. LATEST GUIDANCE IS A LITTLE
FASTER THAN PREVIOUS MODEL RUNS AND SUGGESTS THAT TS COULD REACH
RFD BY ARND 03Z...AND THEN QUICKLY PUSHING TO THE EAST ACROSS THE
CHICAGO AREA TERMINALS. WHILE CONFIDENCE IS RELATIVELY HIGH IN TS
IMPACTING THE TERMINALS OVERNIGHT TONIGHT...TIMING AND DURATION IS
A LITTLE LOWER. ALSO...AS THE MAIN SFC LOW TRACKS ALONG A
DEVELOPING WARM FRONT EXPECTED TO SET THROUGH CNTRL OR NRN IL/IN
AND WITH UPPER LEVEL FLOW SETTING UP TO BE PARALLEL TO THE SFC
FRONT...AN EXTENDED PERIOD OF TSRA IMPACTING THE TERMINALS IS
QUITE POSSIBLE OVERNIGHT AND POSSIBLY EVEN INTO TOMORROW MORNING.
KREIN
//ORD AND MDW CONFIDENCE...UPDATED 20Z...
* MEDIUM TO HIGH CONFIDENCE IN GENERAL WIND TRENDS.
* MEDIUM CONFIDENCE IN LAKE BREEZE DETAILS...AND THAT THE LAKE
BREEZE BOUNDARY WILL REMAIN EAST OF THE TERMINALS.
* MEDIUM TO HIGH CONFIDENCE IN TS IMPACTING THE TERMINALS THIS
EVENING AND TONIGHT...LOWER CONFIDENCE IN EXACT TIMING AND
DURATION.
* MEDIUM CONFIDENCE IN A PERIOD OF MVFR-IFR CIGS/VIS WITH THE
TSRA/PCPN OVERNIGHT TONIGHT AND INTO TOMORROW MORNING.
KREIN
//OUTLOOK FOR ORD/MDW FOR 00Z FRIDAY-12Z WEDNESDAY...UPDATED 12Z...
THURSDAY NIGHT...VFR. WX NIL. NELY WINDS.
FRIDAY...VFR. WX NIL. NELY WINDS.
SATURDAY...VFR. WX NIL. NELY WINDS BACKING NWLY LATE.
SUNDAY...CHANCE TSRA. MVFR POSSIBLE. NWLY WINDS BACKING SWLY.
MONDAY...CHANCE TSRA. MVFR POSSIBLE. SWLY WINDS VEERING NWLY
TUESDAY...SLIGHT CHANCE TSRA. VRBL WINDS.
KREIN
&&
.MARINE...
258 PM CDT
HIGH PRESSURE RIDGING ACROSS THE SOUTHERN GREAT LAKES WILL EXIT
THE AREA TO THE EAST THIS EVENING ALLOWING LOW PRESSURE OVER THE
CENTRAL PLAINS TO MOVE NORTHEAST INTO NORTHERN ILLINOIS BY
THURSDAY MORNING. MEANWHILE A WEAK COLD FRONT ACROSS THE NORTHERN
GREAT LAKES WILL SAG SOUTH AHEAD OF HIGH PRESSURE OVER ONTARIO AND
WASH OUT AS THE AFFOREMENTIONED LOW PRESSURE AREA MOVES INTO
ILLINOIS. AS THIS LOW MOVES EAST TO OHIO THURSDAY NIGHT ITS
ASSOCIATED COLD FRONT WILL DROP SOUTH AWAY FROM THE AREA ALLOWING
ANOTHER AREA OF WEAK HIGH PRESSURE TO BUILD ACROSS THE GREAT
LAKES. THIS HIGH WILL DRIFT EAST SUNDAY NIGHT INTO MONDAY ALLOWING
A SECONDARY COLD FRONT TO SAG SOUTH ACROSS THE NORTHERN GREAT
LAKES.
ED F
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...FLASH FLOOD WATCH...ILZ003-ILZ004-ILZ008-ILZ010-ILZ011-ILZ019-
ILZ021-ILZ032-ILZ039...7 PM WEDNESDAY TO 1 PM THURSDAY.
FLASH FLOOD WATCH...ILZ005-ILZ006-ILZ012-ILZ013-ILZ014-ILZ020-
ILZ022-ILZ023-ILZ033...MIDNIGHT THURSDAY TO 1 PM THURSDAY.
IN...FLASH FLOOD WATCH...INZ001-INZ002-INZ010-INZ011-
INZ019...MIDNIGHT THURSDAY TO 1 PM THURSDAY.
LM...NONE.
&&
$$
VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
WWW.FACEBOOK.COM/NWSCHICAGO
WWW.TWITTER.COM/NWSCHICAGO
WWW.YOUTUBE.COM/NWSCHICAGO
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
318 PM CDT WED JUN 24 2015
.SHORT TERM...
317 PM CDT
THROUGH SATURDAY...
WILL BE PUSHING BACK THE START TIME OF THE FLASH FLOOD WATCH OVER
EASTERN SECTIONS OF THE AREA TILL AROUND 06 UTC THIS
EVENING...OTHERWISE NO CHANGES TO THE WATCH PLANNED.
THE EARLY MORNING SHOWERS AND THUNDERSTORMS OVER WEST CENTRAL
ILLINOIS PUSHED AN OUTFLOW BOUNDARY SOUTHWARD OVER MISSOURI...AND
THIS HAS EFFECTIVELY PUSHED THE SURFACE WARM FRONT AND BETTER
INSTABILITY FARTHER SOUTH OVER MISSOURI. AS SUCH...I HAVE SOME
CONCERNS THAT THE HEAVY RAIN AND SEVERE THREAT...AT LEAST INITIALLY
THIS EVENING MAY BE DELAYED AND FOCUSED OVER WESTERN PORTIONS OF
ILLINOIS AND IOWA. THE HRRR RUNS HAVE BEEN PICKING UP ON THIS
POSSIBILITY OVER THE PAST COUPLE HOURS...AND WITH THE SURFACE
BOUNDARY STILL OVER CENTRAL AND WESTERN SECTIONS OF MISSOURI...I AM
THINKING IT MAY BE HEADING IN THE RIGHT DIRECTION. WITH THIS IN MIND
I DID CUT BACK ON POPS THIS EVENING OVER EASTERN SECTIONS OF THE
REGION AND HAVE PUSHED THE FLASH FLOOD WATCH OFF UNTIL 05 UTC FOR
THE CHICAGO METRO AREA AND NORTHWESTERN INDIANA.
THE CONVECTIVE ACTIVITY OVER IOWA IS ASSOCIATED WITH AN MCV...AND
THIS MAY MOVE OVER PORTIONS OF NORTHERN ILLINOIS LATE THIS
AFTERNOON AND EARLY THIS EVENING. HOWEVER...IT APPEARS WITH THE
INSTABILITY GRADIENT REMAINING TO OUR SOUTHWEST...THUNDERSTORMS WILL
LIKELY BECOME MORE SCATTERED WITH THE EASTWARD EXTENT OF THIS
PRECIPITATION. THEREFORE...ONLY A FEW LINGERING SHOWERS AND PERHAPS
A FEW THUNDERSTORMS MAY MOVE OVER THE AREA THROUGH EARLY THIS
EVENING.
THUNDERSTORMS WILL STILL LIKELY BEGIN TO DEVELOP UPSTREAM OVER
EASTERN IOWA AND INTO WESTERN ILLINOIS THROUGH THE EVENING A
SOUTHWESTERLY LOW LEVEL JET NOSES INTO THIS AREA. THIS WILL RESULT
IN BACKBULDING AND TRAINING THUNDERSTORMS WITH HEAVY RAINFALL.
HOWEVER...IT APPEARS THE MAIN FOCUS FOR THIS ACTIVITY MAY REMAIN JUST
WEST OF MY AREA...AT LEAST FOR MUCH OF THE EVENING. WITH TIME...IT
APPEARS THE FOCUS MAY BEGIN TO SHIFT EASTWARD INTO NORTHEASTERN
ILLINOIS AND NORTHWESTERN INDIANA...BUT THIS MAY NOT BE UNTIL AFTER
MIDNIGHT TONIGHT. HEAVY RAIN RATES WILL STILL BE A CONCERN...AND IT
APPEARS THE HEAVIEST RAIN MAY FALL SOUTH OF INTERSTATE 88.
THE HEAVY RAIN THREAT WILL CONTINUE INTO THE LATE MORNING/EARLY
AFTERNOON ON THURSDAY...ESPECIALLY SOUTH OF I-80 AS THE SURFACE
SYSTEM MOVES OVER THE AREA. HOWEVER...ONCE THE SURFACE LOW PASSES
EAST...THE FRONTAL BOUNDARY WILL SHIFT SOUTH OF THE AREA LATER IN
THE DAY...BRINGING THE SHOWER AND STORM THREAT TO AN END.
AS FOR THE SEVERE THREAT...IT APPEARS THIS TOO MAY END UP BEING
FARTHER SOUTH THAN PREVIOUSLY THOUGHT. ALTHOUGH UNCERTAINTY REMAINS
AS TO HOW THE SEVERE THREAT WILL EVOLVE TONIGHT. IT APPEARS AT THIS
POINT THAT THE HIGHEST THREAT MAY END UP BEING PRIMARILY SOUTH OF
INTERSTATE 80...AND BE MAINLY A DAMAGING WIND THREAT.
MUCH COOLER WEATHER WILL BUILD IN OVER MUCH OF THE REGION IN THE
WAKE OF THIS FRONT. ANOTHER SYSTEM LOOKS TO DEVELOP AND IMPACT THE
OHIO VALLEY REGION LATER FRIDAY INTO EARLY SATURDAY AS AN UPPER
TROUGH DIGS OVER THE LOWER GREAT LAKES REGION. IT APPEARS MOST OF THE
PRECIP WITH THIS SYSTEM WILL REMAIN SOUTH OF MOST OF MY AREA. COOL
CONDITIONS WILL BE THE RULE FOR A FEW DAYS...WITH A BREAK IN THE
WEATHER...FINALLY.
KJB
&&
.LONG TERM...
340 AM CDT
THURSDAY THROUGH TUESDAY...
THE UPPER LEVEL ZONAL FLOW FINALLY SHIFTS EAST LATE THIS WEEK AS AN
UPPER LEVEL TROUGH MOVES OVER THE REGION FRIDAY NIGHT. THE TROUGH
AXIS SHIFTS EAST SATURDAY WITH NORTHWEST FLOW SUNDAY. ANOTHER WEAKER
TROUGH IS POSSIBLE EARLY NEXT WEEK.
A SFC LOW WILL BE OVER NORTHERN IL AND NORTHWEST IN THURSDAY MORNING
AS A DYING MCS SLOWLY SHIFTS EAST. RAISED QPF AMOUNTS THURSDAY
MORNING AS THE DYING MCS SHOULD PRODUCE AT LEAST ANOTHER 0.35-0.5
INCHES OF RAIN SOUTH OF I-88. GUIDANCE DIFFERS ON HOW QUICKLY THE
MCS WILL EXIT THE REGION...BUT HAVE HIGH CONFIDENCE IN DRY
CONDITIONS THURSDAY NIGHT.
SADLY THERE IS A VERY SMALL BREAK BEFORE THE NEXT LOW PRESSURE
BRINGS MORE RAIN AND STORMS TO AREAS SOUTH OF I-80 FRIDAY. THE NEXT
LOW FORMS OVER THE SOUTHERN PLAINS THURSDAY NIGHT. IT THEN PASSES
OVER THE MID MISSISSIPPI VALLEY AND ALONG THE OHIO RIVER THROUGH
SATURDAY NIGHT. IT LOOKS LIKE THE MAJORITY OF PRECIP WILL FALL OVER
CENTRAL AND SOUTHERN IL...BUT KEPT A SLIGHT CHANCE TO CHANCE OF
THUNDERSTORMS SOUTH OF I-88. WE FINALLY SEE A DRY SPELL LATE THIS
WEEK AS THE LOW SHIFTS EAST AND HIGH PRESSURE SPREADS OVERHEAD.
THE NEXT CHANCE OF RAIN AND STORMS ARRIVES EARLY NEXT WEEK AS AN
UPPER LEVEL TROUGH SWINGS THROUGH. GUIDANCE DIFFERS ON HOW STRONG
THE TROUGH WILL BE AND HOW FAR SOUTH IT WILL TRAVEL...BUT HAVE
ENOUGH CONFIDENCE TO KEEP A CHANCE OF PRECIP IN THE FORECAST. WE
COULD SEE MULTIPLE VORTICITY STREAMERS SWING THROUGH AS THE TROUGH
SITS OVERHEAD SO KEPT A CHANCE OF PRECIP FROM SUNDAY NIGHT THROUGH
TUESDAY. DESPITE THE CONSTANT CHANCE OF RAIN...ONLY EXPECTING
PERIODS OF SHOWERS AND STORMS AT THIS POINT AND NOT COMPLETE
RAIN OUTS.
FOR TEMPS...THURSDAY LOOKS LIKE THE WARMEST DAY WITH HIGHS IN THE
UPPER 70S TO LOW 80S. LAKE COOLING WILL KEEP LAKEFRONT LOCATIONS IN
THE LOW 70S. COOLER AIR SINKS SOUTH THURSDAY NIGHT LEADING TO HIGH
TEMPS FRIDAY IN THE 70S WITH 60S ALONG THE LAKE. A SLOW WARM UP IS
EXPECTED WITH HIGHS BACK IN THE LOW 80S TUESDAY.
JEE
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 20Z...
* CHANCE OF LAKE BREEZE DEVELOPMENT LATE THIS AFTERNOON.
* THUNDERSTORMS LIKELY OVERNIGHT TONIGHT...MVFR-IFR CIGS/VIS
LIKELY.
KREIN
//DISCUSSION...UPDATED 18Z...
AT THE SURFACE...A LARGE AREA OF HIGH PRESSURE IS CENTERED ALONG
THE IN/OH BORDER AS A MID LEVEL IMPULSE CROSSING THE MIDDLE
MISSISSIPPI VALLEY IS BRINGING AN AREA OF SHOWERS AND
THUNDERSTORMS FROM IOWA THROUGH CENTRAL IL TO CENTRAL IN. BASED
ON THE LATEST RADAR TRENDS...EXPECT THAT ANY PCPN AND TS SHOULD
REMAIN SOUTH OF OF THE TERMINALS EARLY THIS EVENING...THROUGH IT
COULD CLIP THE SOUTHERN PORTIONS OF THE C90 TRACON AREA. AS THE
CENTER OF THE HIGH CONTINUES TO SHIFT TO THE EAST...WINDS HAVE
BECOME SSWLY AND ARE INCREASING TO ARND 10KT. LATEST RADAR IMAGERY
AND COASTAL OBSERVATIONS SHOW A LAKE BREEZE MOVING ONSHORE NEAR
KUGN...BUT THERE IS LITTLE WESTWARD PROGRESSION AND DO NOT EXPECT
THAT THE BOUNDARY WILL REACH AS FAR WEST AS ORD/MDW.
RATHER...EXPECT THAT WINDS WILL GRADUALLY BACK TO MORE SELY
THROUGH THE AFTERNOON AND INTO THE EVENING IN RESPONSE TO THE
LARGER SCALE PRESSURE PATTERN WITH THE HIGH MOVING OFF TO THE EAST
AND LOW PRESSURE DEVELOPING OVER THE CNTRL PLAINS.
THE OTHER CONCERN FOR THE PERIOD WILL BE TIMING THE NEXT ROUND OF
THUNDERSTORMS TO IMPACT THE REGION. WHILE THE ONGOING PCPN SHOULD
REMAIN SOUTH OF THE TERMINALS...CONFIDENCE IS HIGHER THAT ANOTHER
ROUND OF THUNDERSTORMS WILL DEVELOP TONIGHT OVER THE CNTRL
PLAINS/IOWA AND THEN TRACK EASTWARD. LATEST GUIDANCE IS A LITTLE
FASTER THAN PREVIOUS MODEL RUNS AND SUGGESTS THAT TS COULD REACH
RFD BY ARND 03Z...AND THEN QUICKLY PUSHING TO THE EAST ACROSS THE
CHICAGO AREA TERMINALS. WHILE CONFIDENCE IS RELATIVELY HIGH IN TS
IMPACTING THE TERMINALS OVERNIGHT TONIGHT...TIMING AND DURATION IS
A LITTLE LOWER. ALSO...AS THE MAIN SFC LOW TRACKS ALONG A
DEVELOPING WARM FRONT EXPECTED TO SET THROUGH CNTRL OR NRN IL/IN
AND WITH UPPER LEVEL FLOW SETTING UP TO BE PARALLEL TO THE SFC
FRONT...AN EXTENDED PERIOD OF TSRA IMPACTING THE TERMINALS IS
QUITE POSSIBLE OVERNIGHT AND POSSIBLY EVEN INTO TOMORROW MORNING.
KREIN
//ORD AND MDW CONFIDENCE...UPDATED 20Z...
* MEDIUM TO HIGH CONFIDENCE IN GENERAL WIND TRENDS.
* MEDIUM CONFIDENCE IN LAKE BREEZE DETAILS...AND THAT THE LAKE
BREEZE BOUNDARY WILL REMAIN EAST OF THE TERMINALS.
* MEDIUM TO HIGH CONFIDENCE IN TS IMPACTING THE TERMINALS THIS
EVENING AND TONIGHT...LOWER CONFIDENCE IN EXACT TIMING AND
DURATION.
* MEDIUM CONFIDENCE IN A PERIOD OF MVFR-IFR CIGS/VIS WITH THE
TSRA/PCPN OVERNIGHT TONIGHT AND INTO TOMORROW MORNING.
KREIN
//OUTLOOK FOR ORD/MDW FOR 00Z FRIDAY-12Z WEDNESDAY...UPDATED 12Z...
THURSDAY NIGHT...VFR. WX NIL. NELY WINDS.
FRIDAY...VFR. WX NIL. NELY WINDS.
SATURDAY...VFR. WX NIL. NELY WINDS BACKING NWLY LATE.
SUNDAY...CHANCE TSRA. MVFR POSSIBLE. NWLY WINDS BACKING SWLY.
MONDAY...CHANCE TSRA. MVFR POSSIBLE. SWLY WINDS VEERING NWLY
TUESDAY...SLIGHT CHANCE TSRA. VRBL WINDS.
KREIN
&&
.MARINE...
258 PM CDT
HIGH PRESSURE RIDGING ACROSS THE SOUTHERN GREAT LAKES WILL EXIT
THE AREA TO THE EAST THIS EVENING ALLOWING LOW PRESSURE OVER THE
CENTRAL PLAINS TO MOVE NORTHEAST INTO NORTHERN ILLINOIS BY
THURSDAY MORNING. MEANWHILE A WEAK COLD FRONT ACROSS THE NORTHERN
GREAT LAKES WILL SAG SOUTH AHEAD OF HIGH PRESSURE OVER ONTARIO AND
WASH OUT AS THE AFFOREMENTIONED LOW PRESSURE AREA MOVES INTO
ILLINOIS. AS THIS LOW MOVES EAST TO OHIO THURSDAY NIGHT ITS
ASSOCIATED COLD FRONT WILL DROP SOUTH AWAY FROM THE AREA ALLOWING
ANOTHER AREA OF WEAK HIGH PRESSURE TO BUILD ACROSS THE GREAT
LAKES. THIS HIGH WILL DRIFT EAST SUNDAY NIGHT INTO MONDAY ALLOWING
A SECONDARY COLD FRONT TO SAG SOUTH ACROSS THE NORTHERN GREAT
LAKES.
ED F
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...FLASH FLOOD WATCH...ILZ003-ILZ004-ILZ008-ILZ010-ILZ011-ILZ019-
ILZ021-ILZ032-ILZ039...7 PM WEDNESDAY TO 1 PM THURSDAY.
FLASH FLOOD WATCH...ILZ005-ILZ006-ILZ012-ILZ013-ILZ014-ILZ020-
ILZ022-ILZ023-ILZ033...MIDNIGHT THURSDAY TO 1 PM THURSDAY.
IN...FLASH FLOOD WATCH...INZ001-INZ002-INZ010-INZ011-
INZ019...MIDNIGHT THURSDAY TO 1 PM THURSDAY.
LM...NONE.
&&
$$
VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
WWW.FACEBOOK.COM/NWSCHICAGO
WWW.TWITTER.COM/NWSCHICAGO
WWW.YOUTUBE.COM/NWSCHICAGO
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
258 PM CDT WED JUN 24 2015
.UPDATE...
1217 PM CDT
ALL INDICATIONS THIS MORNING CONTINUE TO POINT TO A CLASSIC TYPE
HEAVY RAIN EVENT ACROSS THE AREA. THE THREAT OF SEVERE THUNDERSTORMS
IS ALSO DECENT WITH THIS ACTIVITY AS WELL LATER THIS EVENING...AND
THIS PRIMARILY LOOKS TO BE IN THE FORM OF STRONG STRAIGHT LINE WINDS.
SHOWERS...WITH SOME EMBEDDED THUNDERSTORMS CONTINUE TO WEAKEN OVER
CENTRAL ILLINOIS AS THEY MOVE AWAY FROM THE BETTER FOCUS OF LAST
NIGHTS LOW LEVEL JET. SATELLITE IMAGERY CONTINUES TO INDICATE CLOUD
TOPS WARMING WITH THIS ACTIVITY...AND EVEN INDICATES SOME BREAKS IN
THE CLOUDS OVER FAR NORTHERN ILLINOIS. FARTHER WEST...HOWEVER...AN
AREA OF CONVECTION OVER EASTERN NE AND NEAR FAR WESTERN IOWA
CONTINUES TO MAINTAIN ITSELF. IT IS CERTAINLY POSSIBLE THAT THIS
ACTIVITY COULD CONTINUE TO MOVE EAST OVER IOWA INTO THIS
AFTERNOON...THEN SHIFT MORE SOUTHEAST ALONG THE MLCAPE GRADIENT. THIS
ACTIVITY...SHOULD IT MAINTAIN ITSELF THOUGH THE DAY...WOULD LIKELY
MISS MOST OF MY AREA...POSSIBLY ONLY IMPACTING MY SOUTHWESTERN
COUNTIES. SOME OF THE LATEST HRRR SOLUTIONS ARE IN LINE WITH THIS
THINKING.
OTHERWISE...THE FOCUS CONTINUES TO CENTER ON THIS EVENING THROUGH
THE OVERNIGHT FOR THE POTENTIAL OF VERY HEAVY RAIN AND FLASH
FLOODING. IT IS STILL ANTICIPATED THAT RENEWED CONVECTION WILL
DEVELOP LATER THIS AFTERNOON/EARLY THIS EVENING OVER PORTIONS OF
EASTERN IOWA INTO NORTHWESTERN ILLINOIS ALONG AND ON THE COOL SIDE
OF A NORTHWARD MOVING WARM FRONTAL BOUNDARY. THIS ACTIVITY WOULD
THEN LIKELY CONTINUE TO GROW UPSCALE AS RENEWED DEVELOPMENT
CONTINUES UPSTREAM THANKS TO A PERSISTENT SOUTHWESTERLY 40+ KT LOW
LEVEL JET CONTINUALLY REPLENISHING THE DEEP MOISTURE. THESE STORMS
WILL OCCUR WITHIN AROUND A 2 INCH PRECIPITABLE WATER
ENVIRONMENT...SO EXTREMELY HEAVY RAIN RATES WILL BE A HIGH CONCERN.
ALSO...WITH CONTINUAL UPSTREAM DEVELOPMENT LOOKING LIKELY...TRAINING
AND BACKBULDING OF CELLS COULD RESULT IN PROLONGED PERIODS OF THESE
VERY HEAVY RAIN RATES OCCURRING OVER THE SAME AREAS. AS SUCH...SOME
ISOLATED AREAS OVER THE AREA COULD EXPERIENCE 4-5+ INCH AMOUNTS OF
RAIN BEFORE THIS ACTIVITY ABATES LATER TONIGHT OR EARLY THURSDAY
MORNING. THERE ARE STILL SOME UNCERTAINTIES ON WHERE EXACTLY THE
HEAVIEST RAINFALL AMOUNTS WILL FALL. HOWEVER...WITH THE ACTIVITY
LIKELY TO MOVE EAST-SOUTHEAST WITH TIME...IT WOULD APPEAR THAT AREAS
ALONG AND SOUTH OF INTERSTATE 88 WOULD LIKELY STAND THE BEST
POTENTIAL TO EXPERIENCE RAINFALL AMOUNTS IN EXCESS OF 1 TO 2 INCHES.
WITHIN THESE TRAINING THUNDERSTORMS...THE KINEMATIC FIELDS OVER THE
AREA WILL ALSO LIKELY SUPPORT FORWARD PROPAGATING EAST-SOUTHEASTWARD
MOVING BOWING SEGMENTS OVER THE AREA. THEREFORE...STRONG DAMAGING
WINDS...PERHAPS IN EXCESS OF 70 MPH...WILL ALSO BE A THREAT WITH
THESE STORMS. A TORNADO OR TWO CAN ALSO NOT BE RULED OUT. HOWEVER...
THIS THREAT APPEARS TO BE THE HIGHEST OVER MY SOUTHEASTERN CWA THIS
EVENING IN CLOSER PROXIMATELY TO THE APPROACHING WARM FRONTAL
BOUNDARY.
KJB
&&
.SHORT TERM...
320 AM CDT
THROUGH WEDNESDAY NIGHT...
STRONG TO SEVERE THUNDERSTORMS COMPRISE THE PRIMARY FORECAST
CONCERNS FOR TODAY AND TONIGHT.
EARLY THIS MORNING...SURFACE HIGH PRESSURE IS CENTERED ACROSS
CENTRAL ILLINOIS PROVIDING MOSTLY CLEAR SKIES AND LIGHT WINDS
ACROSS NORTHERN ILLINOIS AND NORTHWEST INDIANA. FARTHER WEST...A
SURFACE TROUGH IS ANALYZED FROM NORTHERN KANSAS NE ACROSS THE MID-
MISSOURI VALLEY INTO CENTRAL IOWA. WATER VAPOR IMAGERY SHOWS A
SUBTLE/SHEARED WAVE EMBEDDED WITHIN THE MAINLY ZONAL FLOW ALOFT
MOVING ACROSS NORTHERN IOWA WHERE NOCTURNAL THUNDERSTORMS HAVE
DEVELOPED MAINLY FOCUSED ACROSS THE I-80 CORRIDOR IN IOWA. NAM/GFS
INITIALIZE ON THIS AREA OF THUNDERSTORMS AND KEEPS THE FORCING
FOCUSED TO THE WEST OF THE FORECAST AREA THROUGH MOST OF THE DAY
TODAY...ALONG WITH THE INSTABILITY. CANT RULE OUT SOME DECAYING
ELEVATED CONVECTION PROPAGATING INTO THE FORECAST AREA LATER
TODAY...HOWEVER EXPECT MOST OF THE CWA TO BE DRY THIS MORNING INTO
AT LEAST EARLY EVENING. WILL HAVE TO KEEP AN EYE ON HOW EARLY
MORNING CONVECTION IMPACTS THE MOVEMENT OF THE WARM FRONT THROUGH
THE DAY.
THIS EVENING...SURFACE TROUGH/WARM FRONT IS PROGGED TO SETTLE
ACROSS CENTRAL/NORTHERN IOWA INTO NORTHERN ILLINOIS THOUGH THERE
ARE NOTABLE DIFFERENCES AT THIS POINT AS TO EXACTLY HOW FAR NORTH.
VERY STRONG INSTABILITY IS EXPECTED TO DEVELOP SOUTH OF THE FRONT
WITH THUNDERSTORMS EXPECTED TO REDEVELOP/RESTRENGTHEN ACROSS IOWA
AFTERNOON INTO THE EVENING AS ANOTHER SHEARED VORT LOBE TRAVERSES
ACROSS THE REGION AND RIGHT ENTRANCE REGION TO THE LOW LEVEL JET
PROVIDES ADDITIONAL SYNOPTIC SCALE ASCENT. ASSUMING ATMOSPHERE
EFFECTIVELY RECOVERS FROM MORNING CONVECTION...FAVORABLE
SHEAR/INSTABILITY PROFILES...IMPRESSIVE CYCLONICALLY CURVED
HODOGRAPHS AND WHAT SHOULD BE SUFFICIENT FORCING TO OVERCOME ANY
CAPPING INVERSION WILL RESULT IN STRONG TO SEVERE THUNDERSTORMS
DEVELOPING WEST OF THE CWA...POSSIBLY IN A DISCRETE/SUPERCELL MODE
INITIALLY WITH THE FULL GAMUT OF SEVERE WEATHER POSSIBLE.
STRENGTHENING NOCTURNAL LOW LEVEL JET INTO THE EVENING WILL RESULT
IN STORMS MERGING INTO AN MCS AND PUSHING EAST INTO THE LOCAL
FORECAST AREA. AS THIS OCCURS...EXPECT THE PRIMARY SEVERE THREAT
TO CHANGE TO MORE OF A STRAIGHT LINE WIND DAMAGE AND FLOODING
THREAT. CORFIDI VECTORS DROP OFF TO AROUND 5 KT OR SO ON THE
SOUTHERN FLANK OF THE STORMS SO BACKBUILDING AND TRAINING
THUNDERSTORMS REMAIN A CONCERN. A FLASH FLOOD WATCH WAS ISSUED
YESTERDAY AND OPTED TO EXPAND NORTHWARD GIVEN THE TRENDS FROM THE
GFS/NAM...ALTHOUGH CONFIDENCE IS ADMITTEDLY A BIT LOWER ACROSS THE
NORTHERN TIER OF COUNTIES.
DEUBELBEISS
&&
.LONG TERM...
340 AM CDT
THURSDAY THROUGH TUESDAY...
THE UPPER LEVEL ZONAL FLOW FINALLY SHIFTS EAST LATE THIS WEEK AS AN
UPPER LEVEL TROUGH MOVES OVER THE REGION FRIDAY NIGHT. THE TROUGH
AXIS SHIFTS EAST SATURDAY WITH NORTHWEST FLOW SUNDAY. ANOTHER WEAKER
TROUGH IS POSSIBLE EARLY NEXT WEEK.
A SFC LOW WILL BE OVER NORTHERN IL AND NORTHWEST IN THURSDAY MORNING
AS A DYING MCS SLOWLY SHIFTS EAST. RAISED QPF AMOUNTS THURSDAY
MORNING AS THE DYING MCS SHOULD PRODUCE AT LEAST ANOTHER 0.35-0.5
INCHES OF RAIN SOUTH OF I-88. GUIDANCE DIFFERS ON HOW QUICKLY THE
MCS WILL EXIT THE REGION...BUT HAVE HIGH CONFIDENCE IN DRY
CONDITIONS THURSDAY NIGHT.
SADLY THERE IS A VERY SMALL BREAK BEFORE THE NEXT LOW PRESSURE
BRINGS MORE RAIN AND STORMS TO AREAS SOUTH OF I-80 FRIDAY. THE NEXT
LOW FORMS OVER THE SOUTHERN PLAINS THURSDAY NIGHT. IT THEN PASSES
OVER THE MID MISSISSIPPI VALLEY AND ALONG THE OHIO RIVER THROUGH
SATURDAY NIGHT. IT LOOKS LIKE THE MAJORITY OF PRECIP WILL FALL OVER
CENTRAL AND SOUTHERN IL...BUT KEPT A SLIGHT CHANCE TO CHANCE OF
THUNDERSTORMS SOUTH OF I-88. WE FINALLY SEE A DRY SPELL LATE THIS
WEEK AS THE LOW SHIFTS EAST AND HIGH PRESSURE SPREADS OVERHEAD.
THE NEXT CHANCE OF RAIN AND STORMS ARRIVES EARLY NEXT WEEK AS AN
UPPER LEVEL TROUGH SWINGS THROUGH. GUIDANCE DIFFERS ON HOW STRONG
THE TROUGH WILL BE AND HOW FAR SOUTH IT WILL TRAVEL...BUT HAVE
ENOUGH CONFIDENCE TO KEEP A CHANCE OF PRECIP IN THE FORECAST. WE
COULD SEE MULTIPLE VORTICITY STREAMERS SWING THROUGH AS THE TROUGH
SITS OVERHEAD SO KEPT A CHANCE OF PRECIP FROM SUNDAY NIGHT THROUGH
TUESDAY. DESPITE THE CONSTANT CHANCE OF RAIN...ONLY EXPECTING
PERIODS OF SHOWERS AND STORMS AT THIS POINT AND NOT COMPLETE
RAIN OUTS.
FOR TEMPS...THURSDAY LOOKS LIKE THE WARMEST DAY WITH HIGHS IN THE
UPPER 70S TO LOW 80S. LAKE COOLING WILL KEEP LAKEFRONT LOCATIONS IN
THE LOW 70S. COOLER AIR SINKS SOUTH THURSDAY NIGHT LEADING TO HIGH
TEMPS FRIDAY IN THE 70S WITH 60S ALONG THE LAKE. A SLOW WARM UP IS
EXPECTED WITH HIGHS BACK IN THE LOW 80S TUESDAY.
JEE
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 20Z...
* CHANCE OF LAKE BREEZE DEVELOPMENT LATE THIS AFTERNOON.
* THUNDERSTORMS LIKELY OVERNIGHT TONIGHT...MVFR-IFR CIGS/VIS
LIKELY.
KREIN
//DISCUSSION...UPDATED 18Z...
AT THE SURFACE...A LARGE AREA OF HIGH PRESSURE IS CENTERED ALONG
THE IN/OH BORDER AS A MID LEVEL IMPULSE CROSSING THE MIDDLE
MISSISSIPPI VALLEY IS BRINGING AN AREA OF SHOWERS AND
THUNDERSTORMS FROM IOWA THROUGH CENTRAL IL TO CENTRAL IN. BASED
ON THE LATEST RADAR TRENDS...EXPECT THAT ANY PCPN AND TS SHOULD
REMAIN SOUTH OF OF THE TERMINALS EARLY THIS EVENING...THROUGH IT
COULD CLIP THE SOUTHERN PORTIONS OF THE C90 TRACON AREA. AS THE
CENTER OF THE HIGH CONTINUES TO SHIFT TO THE EAST...WINDS HAVE
BECOME SSWLY AND ARE INCREASING TO ARND 10KT. LATEST RADAR IMAGERY
AND COASTAL OBSERVATIONS SHOW A LAKE BREEZE MOVING ONSHORE NEAR
KUGN...BUT THERE IS LITTLE WESTWARD PROGRESSION AND DO NOT EXPECT
THAT THE BOUNDARY WILL REACH AS FAR WEST AS ORD/MDW.
RATHER...EXPECT THAT WINDS WILL GRADUALLY BACK TO MORE SELY
THROUGH THE AFTERNOON AND INTO THE EVENING IN RESPONSE TO THE
LARGER SCALE PRESSURE PATTERN WITH THE HIGH MOVING OFF TO THE EAST
AND LOW PRESSURE DEVELOPING OVER THE CNTRL PLAINS.
THE OTHER CONCERN FOR THE PERIOD WILL BE TIMING THE NEXT ROUND OF
THUNDERSTORMS TO IMPACT THE REGION. WHILE THE ONGOING PCPN SHOULD
REMAIN SOUTH OF THE TERMINALS...CONFIDENCE IS HIGHER THAT ANOTHER
ROUND OF THUNDERSTORMS WILL DEVELOP TONIGHT OVER THE CNTRL
PLAINS/IOWA AND THEN TRACK EASTWARD. LATEST GUIDANCE IS A LITTLE
FASTER THAN PREVIOUS MODEL RUNS AND SUGGESTS THAT TS COULD REACH
RFD BY ARND 03Z...AND THEN QUICKLY PUSHING TO THE EAST ACROSS THE
CHICAGO AREA TERMINALS. WHILE CONFIDENCE IS RELATIVELY HIGH IN TS
IMPACTING THE TERMINALS OVERNIGHT TONIGHT...TIMING AND DURATION IS
A LITTLE LOWER. ALSO...AS THE MAIN SFC LOW TRACKS ALONG A
DEVELOPING WARM FRONT EXPECTED TO SET THROUGH CNTRL OR NRN IL/IN
AND WITH UPPER LEVEL FLOW SETTING UP TO BE PARALLEL TO THE SFC
FRONT...AN EXTENDED PERIOD OF TSRA IMPACTING THE TERMINALS IS
QUITE POSSIBLE OVERNIGHT AND POSSIBLY EVEN INTO TOMORROW MORNING.
KREIN
//ORD AND MDW CONFIDENCE...UPDATED 20Z...
* MEDIUM TO HIGH CONFIDENCE IN GENERAL WIND TRENDS.
* MEDIUM CONFIDENCE IN LAKE BREEZE DETAILS...AND THAT THE LAKE
BREEZE BOUNDARY WILL REMAIN EAST OF THE TERMINALS.
* MEDIUM TO HIGH CONFIDENCE IN TS IMPACTING THE TERMINALS THIS
EVENING AND TONIGHT...LOWER CONFIDENCE IN EXACT TIMING AND
DURATION.
* MEDIUM CONFIDENCE IN A PERIOD OF MVFR-IFR CIGS/VIS WITH THE
TSRA/PCPN OVERNIGHT TONIGHT AND INTO TOMORROW MORNING.
KREIN
//OUTLOOK FOR ORD/MDW FOR 00Z FRIDAY-12Z WEDNESDAY...UPDATED 12Z...
THURSDAY NIGHT...VFR. WX NIL. NELY WINDS.
FRIDAY...VFR. WX NIL. NELY WINDS.
SATURDAY...VFR. WX NIL. NELY WINDS BACKING NWLY LATE.
SUNDAY...CHANCE TSRA. MVFR POSSIBLE. NWLY WINDS BACKING SWLY.
MONDAY...CHANCE TSRA. MVFR POSSIBLE. SWLY WINDS VEERING NWLY
TUESDAY...SLIGHT CHANCE TSRA. VRBL WINDS.
KREIN
&&
.MARINE...
258 PM CDT
HIGH PRESSURE RIDGING ACROSS THE SOUTHERN GREAT LAKES WILL EXIT
THE AREA TO THE EAST THIS EVENING ALLOWING LOW PRESSURE OVER THE
CENTRAL PLAINS TO MOVE NORTHEAST INTO NORTHERN ILLINOIS BY
THURSDAY MORNING. MEANWHILE A WEAK COLD FRONT ACROSS THE NORTHERN
GREAT LAKES WILL SAG SOUTH AHEAD OF HIGH PRESSURE OVER ONTARIO AND
WASH OUT AS THE AFFOREMENTIONED LOW PRESSURE AREA MOVES INTO
ILLINOIS. AS THIS LOW MOVES EAST TO OHIO THURSDAY NIGHT ITS
ASSOCIATED COLD FRONT WILL DROP SOUTH AWAY FROM THE AREA ALLOWING
ANOTHER AREA OF WEAK HIGH PRESSURE TO BUILD ACROSS THE GREAT
LAKES. THIS HIGH WILL DRIFT EAST SUNDAY NIGHT INTO MONDAY ALLOWING
A SECONDARY COLD FRONT TO SAG SOUTH ACROSS THE NORTHERN GREAT
LAKES.
ED F
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...FLASH FLOOD WATCH...ILZ003-ILZ004-ILZ008-ILZ010-ILZ011-ILZ019-
ILZ021-ILZ032-ILZ039...7 PM WEDNESDAY TO 1 PM THURSDAY.
FLASH FLOOD WATCH...ILZ005-ILZ006-ILZ012-ILZ013-ILZ014-ILZ020-
ILZ022-ILZ023-ILZ033...MIDNIGHT THURSDAY TO 1 PM THURSDAY.
IN...FLASH FLOOD WATCH...INZ001-INZ002-INZ010-INZ011-
INZ019...MIDNIGHT THURSDAY TO 1 PM THURSDAY.
LM...NONE.
&&
$$
VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
WWW.FACEBOOK.COM/NWSCHICAGO
WWW.TWITTER.COM/NWSCHICAGO
WWW.YOUTUBE.COM/NWSCHICAGO
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
235 PM CDT WED JUN 24 2015
.UPDATE...
1217 PM CDT
ALL INDICATIONS THIS MORNING CONTINUE TO POINT TO A CLASSIC TYPE
HEAVY RAIN EVENT ACROSS THE AREA. THE THREAT OF SEVERE THUNDERSTORMS
IS ALSO DECENT WITH THIS ACTIVITY AS WELL LATER THIS EVENING...AND
THIS PRIMARILY LOOKS TO BE IN THE FORM OF STRONG STRAIGHT LINE WINDS.
SHOWERS...WITH SOME EMBEDDED THUNDERSTORMS CONTINUE TO WEAKEN OVER
CENTRAL ILLINOIS AS THEY MOVE AWAY FROM THE BETTER FOCUS OF LAST
NIGHTS LOW LEVEL JET. SATELLITE IMAGERY CONTINUES TO INDICATE CLOUD
TOPS WARMING WITH THIS ACTIVITY...AND EVEN INDICATES SOME BREAKS IN
THE CLOUDS OVER FAR NORTHERN ILLINOIS. FARTHER WEST...HOWEVER...AN
AREA OF CONVECTION OVER EASTERN NE AND NEAR FAR WESTERN IOWA
CONTINUES TO MAINTAIN ITSELF. IT IS CERTAINLY POSSIBLE THAT THIS
ACTIVITY COULD CONTINUE TO MOVE EAST OVER IOWA INTO THIS
AFTERNOON...THEN SHIFT MORE SOUTHEAST ALONG THE MLCAPE GRADIENT. THIS
ACTIVITY...SHOULD IT MAINTAIN ITSELF THOUGH THE DAY...WOULD LIKELY
MISS MOST OF MY AREA...POSSIBLY ONLY IMPACTING MY SOUTHWESTERN
COUNTIES. SOME OF THE LATEST HRRR SOLUTIONS ARE IN LINE WITH THIS
THINKING.
OTHERWISE...THE FOCUS CONTINUES TO CENTER ON THIS EVENING THROUGH
THE OVERNIGHT FOR THE POTENTIAL OF VERY HEAVY RAIN AND FLASH
FLOODING. IT IS STILL ANTICIPATED THAT RENEWED CONVECTION WILL
DEVELOP LATER THIS AFTERNOON/EARLY THIS EVENING OVER PORTIONS OF
EASTERN IOWA INTO NORTHWESTERN ILLINOIS ALONG AND ON THE COOL SIDE
OF A NORTHWARD MOVING WARM FRONTAL BOUNDARY. THIS ACTIVITY WOULD
THEN LIKELY CONTINUE TO GROW UPSCALE AS RENEWED DEVELOPMENT
CONTINUES UPSTREAM THANKS TO A PERSISTENT SOUTHWESTERLY 40+ KT LOW
LEVEL JET CONTINUALLY REPLENISHING THE DEEP MOISTURE. THESE STORMS
WILL OCCUR WITHIN AROUND A 2 INCH PRECIPITABLE WATER
ENVIRONMENT...SO EXTREMELY HEAVY RAIN RATES WILL BE A HIGH CONCERN.
ALSO...WITH CONTINUAL UPSTREAM DEVELOPMENT LOOKING LIKELY...TRAINING
AND BACKBULDING OF CELLS COULD RESULT IN PROLONGED PERIODS OF THESE
VERY HEAVY RAIN RATES OCCURRING OVER THE SAME AREAS. AS SUCH...SOME
ISOLATED AREAS OVER THE AREA COULD EXPERIENCE 4-5+ INCH AMOUNTS OF
RAIN BEFORE THIS ACTIVITY ABATES LATER TONIGHT OR EARLY THURSDAY
MORNING. THERE ARE STILL SOME UNCERTAINTIES ON WHERE EXACTLY THE
HEAVIEST RAINFALL AMOUNTS WILL FALL. HOWEVER...WITH THE ACTIVITY
LIKELY TO MOVE EAST-SOUTHEAST WITH TIME...IT WOULD APPEAR THAT AREAS
ALONG AND SOUTH OF INTERSTATE 88 WOULD LIKELY STAND THE BEST
POTENTIAL TO EXPERIENCE RAINFALL AMOUNTS IN EXCESS OF 1 TO 2 INCHES.
WITHIN THESE TRAINING THUNDERSTORMS...THE KINEMATIC FIELDS OVER THE
AREA WILL ALSO LIKELY SUPPORT FORWARD PROPAGATING EAST-SOUTHEASTWARD
MOVING BOWING SEGMENTS OVER THE AREA. THEREFORE...STRONG DAMAGING
WINDS...PERHAPS IN EXCESS OF 70 MPH...WILL ALSO BE A THREAT WITH
THESE STORMS. A TORNADO OR TWO CAN ALSO NOT BE RULED OUT. HOWEVER...
THIS THREAT APPEARS TO BE THE HIGHEST OVER MY SOUTHEASTERN CWA THIS
EVENING IN CLOSER PROXIMATELY TO THE APPROACHING WARM FRONTAL
BOUNDARY.
KJB
&&
.SHORT TERM...
320 AM CDT
THROUGH WEDNESDAY NIGHT...
STRONG TO SEVERE THUNDERSTORMS COMPRISE THE PRIMARY FORECAST
CONCERNS FOR TODAY AND TONIGHT.
EARLY THIS MORNING...SURFACE HIGH PRESSURE IS CENTERED ACROSS
CENTRAL ILLINOIS PROVIDING MOSTLY CLEAR SKIES AND LIGHT WINDS
ACROSS NORTHERN ILLINOIS AND NORTHWEST INDIANA. FARTHER WEST...A
SURFACE TROUGH IS ANALYZED FROM NORTHERN KANSAS NE ACROSS THE MID-
MISSOURI VALLEY INTO CENTRAL IOWA. WATER VAPOR IMAGERY SHOWS A
SUBTLE/SHEARED WAVE EMBEDDED WITHIN THE MAINLY ZONAL FLOW ALOFT
MOVING ACROSS NORTHERN IOWA WHERE NOCTURNAL THUNDERSTORMS HAVE
DEVELOPED MAINLY FOCUSED ACROSS THE I-80 CORRIDOR IN IOWA. NAM/GFS
INITIALIZE ON THIS AREA OF THUNDERSTORMS AND KEEPS THE FORCING
FOCUSED TO THE WEST OF THE FORECAST AREA THROUGH MOST OF THE DAY
TODAY...ALONG WITH THE INSTABILITY. CANT RULE OUT SOME DECAYING
ELEVATED CONVECTION PROPAGATING INTO THE FORECAST AREA LATER
TODAY...HOWEVER EXPECT MOST OF THE CWA TO BE DRY THIS MORNING INTO
AT LEAST EARLY EVENING. WILL HAVE TO KEEP AN EYE ON HOW EARLY
MORNING CONVECTION IMPACTS THE MOVEMENT OF THE WARM FRONT THROUGH
THE DAY.
THIS EVENING...SURFACE TROUGH/WARM FRONT IS PROGGED TO SETTLE
ACROSS CENTRAL/NORTHERN IOWA INTO NORTHERN ILLINOIS THOUGH THERE
ARE NOTABLE DIFFERENCES AT THIS POINT AS TO EXACTLY HOW FAR NORTH.
VERY STRONG INSTABILITY IS EXPECTED TO DEVELOP SOUTH OF THE FRONT
WITH THUNDERSTORMS EXPECTED TO REDEVELOP/RESTRENGTHEN ACROSS IOWA
AFTERNOON INTO THE EVENING AS ANOTHER SHEARED VORT LOBE TRAVERSES
ACROSS THE REGION AND RIGHT ENTRANCE REGION TO THE LOW LEVEL JET
PROVIDES ADDITIONAL SYNOPTIC SCALE ASCENT. ASSUMING ATMOSPHERE
EFFECTIVELY RECOVERS FROM MORNING CONVECTION...FAVORABLE
SHEAR/INSTABILITY PROFILES...IMPRESSIVE CYCLONICALLY CURVED
HODOGRAPHS AND WHAT SHOULD BE SUFFICIENT FORCING TO OVERCOME ANY
CAPPING INVERSION WILL RESULT IN STRONG TO SEVERE THUNDERSTORMS
DEVELOPING WEST OF THE CWA...POSSIBLY IN A DISCRETE/SUPERCELL MODE
INITIALLY WITH THE FULL GAMUT OF SEVERE WEATHER POSSIBLE.
STRENGTHENING NOCTURNAL LOW LEVEL JET INTO THE EVENING WILL RESULT
IN STORMS MERGING INTO AN MCS AND PUSHING EAST INTO THE LOCAL
FORECAST AREA. AS THIS OCCURS...EXPECT THE PRIMARY SEVERE THREAT
TO CHANGE TO MORE OF A STRAIGHT LINE WIND DAMAGE AND FLOODING
THREAT. CORFIDI VECTORS DROP OFF TO AROUND 5 KT OR SO ON THE
SOUTHERN FLANK OF THE STORMS SO BACKBUILDING AND TRAINING
THUNDERSTORMS REMAIN A CONCERN. A FLASH FLOOD WATCH WAS ISSUED
YESTERDAY AND OPTED TO EXPAND NORTHWARD GIVEN THE TRENDS FROM THE
GFS/NAM...ALTHOUGH CONFIDENCE IS ADMITTEDLY A BIT LOWER ACROSS THE
NORTHERN TIER OF COUNTIES.
DEUBELBEISS
&&
.LONG TERM...
340 AM CDT
THURSDAY THROUGH TUESDAY...
THE UPPER LEVEL ZONAL FLOW FINALLY SHIFTS EAST LATE THIS WEEK AS AN
UPPER LEVEL TROUGH MOVES OVER THE REGION FRIDAY NIGHT. THE TROUGH
AXIS SHIFTS EAST SATURDAY WITH NORTHWEST FLOW SUNDAY. ANOTHER WEAKER
TROUGH IS POSSIBLE EARLY NEXT WEEK.
A SFC LOW WILL BE OVER NORTHERN IL AND NORTHWEST IN THURSDAY MORNING
AS A DYING MCS SLOWLY SHIFTS EAST. RAISED QPF AMOUNTS THURSDAY
MORNING AS THE DYING MCS SHOULD PRODUCE AT LEAST ANOTHER 0.35-0.5
INCHES OF RAIN SOUTH OF I-88. GUIDANCE DIFFERS ON HOW QUICKLY THE
MCS WILL EXIT THE REGION...BUT HAVE HIGH CONFIDENCE IN DRY
CONDITIONS THURSDAY NIGHT.
SADLY THERE IS A VERY SMALL BREAK BEFORE THE NEXT LOW PRESSURE
BRINGS MORE RAIN AND STORMS TO AREAS SOUTH OF I-80 FRIDAY. THE NEXT
LOW FORMS OVER THE SOUTHERN PLAINS THURSDAY NIGHT. IT THEN PASSES
OVER THE MID MISSISSIPPI VALLEY AND ALONG THE OHIO RIVER THROUGH
SATURDAY NIGHT. IT LOOKS LIKE THE MAJORITY OF PRECIP WILL FALL OVER
CENTRAL AND SOUTHERN IL...BUT KEPT A SLIGHT CHANCE TO CHANCE OF
THUNDERSTORMS SOUTH OF I-88. WE FINALLY SEE A DRY SPELL LATE THIS
WEEK AS THE LOW SHIFTS EAST AND HIGH PRESSURE SPREADS OVERHEAD.
THE NEXT CHANCE OF RAIN AND STORMS ARRIVES EARLY NEXT WEEK AS AN
UPPER LEVEL TROUGH SWINGS THROUGH. GUIDANCE DIFFERS ON HOW STRONG
THE TROUGH WILL BE AND HOW FAR SOUTH IT WILL TRAVEL...BUT HAVE
ENOUGH CONFIDENCE TO KEEP A CHANCE OF PRECIP IN THE FORECAST. WE
COULD SEE MULTIPLE VORTICITY STREAMERS SWING THROUGH AS THE TROUGH
SITS OVERHEAD SO KEPT A CHANCE OF PRECIP FROM SUNDAY NIGHT THROUGH
TUESDAY. DESPITE THE CONSTANT CHANCE OF RAIN...ONLY EXPECTING
PERIODS OF SHOWERS AND STORMS AT THIS POINT AND NOT COMPLETE
RAIN OUTS.
FOR TEMPS...THURSDAY LOOKS LIKE THE WARMEST DAY WITH HIGHS IN THE
UPPER 70S TO LOW 80S. LAKE COOLING WILL KEEP LAKEFRONT LOCATIONS IN
THE LOW 70S. COOLER AIR SINKS SOUTH THURSDAY NIGHT LEADING TO HIGH
TEMPS FRIDAY IN THE 70S WITH 60S ALONG THE LAKE. A SLOW WARM UP IS
EXPECTED WITH HIGHS BACK IN THE LOW 80S TUESDAY.
JEE
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 20Z...
* CHANCE OF LAKE BREEZE DEVELOPMENT LATE THIS AFTERNOON.
* THUNDERSTORMS LIKELY OVERNIGHT TONIGHT...MVFR-IFR CIGS/VIS
LIKELY.
KREIN
//DISCUSSION...UPDATED 18Z...
AT THE SURFACE...A LARGE AREA OF HIGH PRESSURE IS CENTERED ALONG
THE IN/OH BORDER AS A MID LEVEL IMPULSE CROSSING THE MIDDLE
MISSISSIPPI VALLEY IS BRINGING AN AREA OF SHOWERS AND
THUNDERSTORMS FROM IOWA THROUGH CENTRAL IL TO CENTRAL IN. BASED
ON THE LATEST RADAR TRENDS...EXPECT THAT ANY PCPN AND TS SHOULD
REMAIN SOUTH OF OF THE TERMINALS EARLY THIS EVENING...THROUGH IT
COULD CLIP THE SOUTHERN PORTIONS OF THE C90 TRACON AREA. AS THE
CENTER OF THE HIGH CONTINUES TO SHIFT TO THE EAST...WINDS HAVE
BECOME SSWLY AND ARE INCREASING TO ARND 10KT. LATEST RADAR IMAGERY
AND COASTAL OBSERVATIONS SHOW A LAKE BREEZE MOVING ONSHORE NEAR
KUGN...BUT THERE IS LITTLE WESTWARD PROGRESSION AND DO NOT EXPECT
THAT THE BOUNDARY WILL REACH AS FAR WEST AS ORD/MDW.
RATHER...EXPECT THAT WINDS WILL GRADUALLY BACK TO MORE SELY
THROUGH THE AFTERNOON AND INTO THE EVENING IN RESPONSE TO THE
LARGER SCALE PRESSURE PATTERN WITH THE HIGH MOVING OFF TO THE EAST
AND LOW PRESSURE DEVELOPING OVER THE CNTRL PLAINS.
THE OTHER CONCERN FOR THE PERIOD WILL BE TIMING THE NEXT ROUND OF
THUNDERSTORMS TO IMPACT THE REGION. WHILE THE ONGOING PCPN SHOULD
REMAIN SOUTH OF THE TERMINALS...CONFIDENCE IS HIGHER THAT ANOTHER
ROUND OF THUNDERSTORMS WILL DEVELOP TONIGHT OVER THE CNTRL
PLAINS/IOWA AND THEN TRACK EASTWARD. LATEST GUIDANCE IS A LITTLE
FASTER THAN PREVIOUS MODEL RUNS AND SUGGESTS THAT TS COULD REACH
RFD BY ARND 03Z...AND THEN QUICKLY PUSHING TO THE EAST ACROSS THE
CHICAGO AREA TERMINALS. WHILE CONFIDENCE IS RELATIVELY HIGH IN TS
IMPACTING THE TERMINALS OVERNIGHT TONIGHT...TIMING AND DURATION IS
A LITTLE LOWER. ALSO...AS THE MAIN SFC LOW TRACKS ALONG A
DEVELOPING WARM FRONT EXPECTED TO SET THROUGH CNTRL OR NRN IL/IN
AND WITH UPPER LEVEL FLOW SETTING UP TO BE PARALLEL TO THE SFC
FRONT...AN EXTENDED PERIOD OF TSRA IMPACTING THE TERMINALS IS
QUITE POSSIBLE OVERNIGHT AND POSSIBLY EVEN INTO TOMORROW MORNING.
KREIN
//ORD AND MDW CONFIDENCE...UPDATED 20Z...
* MEDIUM TO HIGH CONFIDENCE IN GENERAL WIND TRENDS.
* MEDIUM CONFIDENCE IN LAKE BREEZE DETAILS...AND THAT THE LAKE
BREEZE BOUNDARY WILL REMAIN EAST OF THE TERMINALS.
* MEDIUM TO HIGH CONFIDENCE IN TS IMPACTING THE TERMINALS THIS
EVENING AND TONIGHT...LOWER CONFIDENCE IN EXACT TIMING AND
DURATION.
* MEDIUM CONFIDENCE IN A PERIOD OF MVFR-IFR CIGS/VIS WITH THE
TSRA/PCPN OVERNIGHT TONIGHT AND INTO TOMORROW MORNING.
KREIN
//OUTLOOK FOR ORD/MDW FOR 00Z FRIDAY-12Z WEDNESDAY...UPDATED 12Z...
THURSDAY NIGHT...VFR. WX NIL. NELY WINDS.
FRIDAY...VFR. WX NIL. NELY WINDS.
SATURDAY...VFR. WX NIL. NELY WINDS BACKING NWLY LATE.
SUNDAY...CHANCE TSRA. MVFR POSSIBLE. NWLY WINDS BACKING SWLY.
MONDAY...CHANCE TSRA. MVFR POSSIBLE. SWLY WINDS VEERING NWLY
TUESDAY...SLIGHT CHANCE TSRA. VRBL WINDS.
KREIN
&&
.MARINE...
410 AM CDT
HIGH PRESSURE IS OVER THE REGION WITH LIGHT SOUTHWEST WINDS. WINDS
REMAIN LIGHT AND BECOME EAST THURSDAY MORNING AS A LOW PRESSURE
SYSTEM MOVES OVER THE SOUTHERN END OF THE LAKE. GUIDANCE DIFFERS ON
HOW STRONG THE LOW WILL BE SO WIND SPEEDS COULD BE STRONGER OVER THE
SOUTHERN END OF THE LAKE IF THE LOW IS STRONGER. THE LOW SHIFTS
EAST AND ANOTHER LOW PASSES WELL SOUTH OF THE LAKE OVER THE OHIO
RIVER LATE THIS WEEK. PERSISTENT NORTH TO NORTHEAST WINDS AT 20KT OR
LESS ARE EXPECTED THROUGH SATURDAY NIGHT. HIGH PRESSURE SPREADS
SOUTH OF THE LAKE WHILE A LOW SPREADS OVER THE LAKE SUNDAY NIGHT
WITH WINDS BCMG SOUTH SUNDAY EVENING AND REMAINING SOUTH TO
SOUTHWEST THROUGH MONDAY NIGHT.
JEE
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...FLASH FLOOD WATCH...ILZ003-ILZ004-ILZ005-ILZ006-ILZ008-ILZ010-
ILZ011-ILZ012-ILZ013-ILZ014-ILZ019-ILZ020-ILZ021-ILZ022-
ILZ023-ILZ032-ILZ033-ILZ039...7 PM WEDNESDAY TO 1 PM
THURSDAY.
IN...FLASH FLOOD WATCH...INZ001-INZ002-INZ010-INZ011-INZ019...7 PM
WEDNESDAY TO 1 PM THURSDAY.
LM...NONE.
&&
$$
VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
WWW.FACEBOOK.COM/NWSCHICAGO
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WWW.YOUTUBE.COM/NWSCHICAGO
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
1238 PM CDT WED JUN 24 2015
.UPDATE...
1217 PM CDT
ALL INDICATIONS THIS MORNING CONTINUE TO POINT TO A CLASSIC TYPE
HEAVY RAIN EVENT ACROSS THE AREA. THE THREAT OF SEVERE THUNDERSTORMS
IS ALSO DECENT WITH THIS ACTIVITY AS WELL LATER THIS EVENING...AND
THIS PRIMARILY LOOKS TO BE IN THE FORM OF STRONG STRAIGHT LINE WINDS.
SHOWERS...WITH SOME EMBEDDED THUNDERSTORMS CONTINUE TO WEAKEN OVER
CENTRAL ILLINOIS AS THEY MOVE AWAY FROM THE BETTER FOCUS OF LAST
NIGHTS LOW LEVEL JET. SATELLITE IMAGERY CONTINUES TO INDICATE CLOUD
TOPS WARMING WITH THIS ACTIVITY...AND EVEN INDICATES SOME BREAKS IN
THE CLOUDS OVER FAR NORTHERN ILLINOIS. FARTHER WEST...HOWEVER...AN
AREA OF CONVECTION OVER EASTERN NE AND NEAR FAR WESTERN IOWA
CONTINUES TO MAINTAIN ITSELF. IT IS CERTAINLY POSSIBLE THAT THIS
ACTIVITY COULD CONTINUE TO MOVE EAST OVER IOWA INTO THIS
AFTERNOON...THEN SHIFT MORE SOUTHEAST ALONG THE MLCAPE GRADIENT. THIS
ACTIVITY...SHOULD IT MAINTAIN ITSELF THOUGH THE DAY...WOULD LIKELY
MISS MOST OF MY AREA...POSSIBLY ONLY IMPACTING MY SOUTHWESTERN
COUNTIES. SOME OF THE LATEST HRRR SOLUTIONS ARE IN LINE WITH THIS
THINKING.
OTHERWISE...THE FOCUS CONTINUES TO CENTER ON THIS EVENING THROUGH
THE OVERNIGHT FOR THE POTENTIAL OF VERY HEAVY RAIN AND FLASH
FLOODING. IT IS STILL ANTICIPATED THAT RENEWED CONVECTION WILL
DEVELOP LATER THIS AFTERNOON/EARLY THIS EVENING OVER PORTIONS OF
EASTERN IOWA INTO NORTHWESTERN ILLINOIS ALONG AND ON THE COOL SIDE
OF A NORTHWARD MOVING WARM FRONTAL BOUNDARY. THIS ACTIVITY WOULD
THEN LIKELY CONTINUE TO GROW UPSCALE AS RENEWED DEVELOPMENT
CONTINUES UPSTREAM THANKS TO A PERSISTENT SOUTHWESTERLY 40+ KT LOW
LEVEL JET CONTINUALLY REPLENISHING THE DEEP MOISTURE. THESE STORMS
WILL OCCUR WITHIN AROUND A 2 INCH PRECIPITABLE WATER
ENVIRONMENT...SO EXTREMELY HEAVY RAIN RATES WILL BE A HIGH CONCERN.
ALSO...WITH CONTINUAL UPSTREAM DEVELOPMENT LOOKING LIKELY...TRAINING
AND BACKBULDING OF CELLS COULD RESULT IN PROLONGED PERIODS OF THESE
VERY HEAVY RAIN RATES OCCURRING OVER THE SAME AREAS. AS SUCH...SOME
ISOLATED AREAS OVER THE AREA COULD EXPERIENCE 4-5+ INCH AMOUNTS OF
RAIN BEFORE THIS ACTIVITY ABATES LATER TONIGHT OR EARLY THURSDAY
MORNING. THERE ARE STILL SOME UNCERTAINTIES ON WHERE EXACTLY THE
HEAVIEST RAINFALL AMOUNTS WILL FALL. HOWEVER...WITH THE ACTIVITY
LIKELY TO MOVE EAST-SOUTHEAST WITH TIME...IT WOULD APPEAR THAT AREAS
ALONG AND SOUTH OF INTERSTATE 88 WOULD LIKELY STAND THE BEST
POTENTIAL TO EXPERIENCE RAINFALL AMOUNTS IN EXCESS OF 1 TO 2 INCHES.
WITHIN THESE TRAINING THUNDERSTORMS...THE KINEMATIC FIELDS OVER THE
AREA WILL ALSO LIKELY SUPPORT FORWARD PROPAGATING EAST-SOUTHEASTWARD
MOVING BOWING SEGMENTS OVER THE AREA. THEREFORE...STRONG DAMAGING
WINDS...PERHAPS IN EXCESS OF 70 MPH...WILL ALSO BE A THREAT WITH
THESE STORMS. A TORNADO OR TWO CAN ALSO NOT BE RULED OUT. HOWEVER...
THIS THREAT APPEARS TO BE THE HIGHEST OVER MY SOUTHEASTERN CWA THIS
EVENING IN CLOSER PROXIMATELY TO THE APPROACHING WARM FRONTAL
BOUNDARY.
KJB
&&
.SHORT TERM...
320 AM CDT
THROUGH WEDNESDAY NIGHT...
STRONG TO SEVERE THUNDERSTORMS COMPRISE THE PRIMARY FORECAST
CONCERNS FOR TODAY AND TONIGHT.
EARLY THIS MORNING...SURFACE HIGH PRESSURE IS CENTERED ACROSS
CENTRAL ILLINOIS PROVIDING MOSTLY CLEAR SKIES AND LIGHT WINDS
ACROSS NORTHERN ILLINOIS AND NORTHWEST INDIANA. FARTHER WEST...A
SURFACE TROUGH IS ANALYZED FROM NORTHERN KANSAS NE ACROSS THE MID-
MISSOURI VALLEY INTO CENTRAL IOWA. WATER VAPOR IMAGERY SHOWS A
SUBTLE/SHEARED WAVE EMBEDDED WITHIN THE MAINLY ZONAL FLOW ALOFT
MOVING ACROSS NORTHERN IOWA WHERE NOCTURNAL THUNDERSTORMS HAVE
DEVELOPED MAINLY FOCUSED ACROSS THE I-80 CORRIDOR IN IOWA. NAM/GFS
INITIALIZE ON THIS AREA OF THUNDERSTORMS AND KEEPS THE FORCING
FOCUSED TO THE WEST OF THE FORECAST AREA THROUGH MOST OF THE DAY
TODAY...ALONG WITH THE INSTABILITY. CANT RULE OUT SOME DECAYING
ELEVATED CONVECTION PROPAGATING INTO THE FORECAST AREA LATER
TODAY...HOWEVER EXPECT MOST OF THE CWA TO BE DRY THIS MORNING INTO
AT LEAST EARLY EVENING. WILL HAVE TO KEEP AN EYE ON HOW EARLY
MORNING CONVECTION IMPACTS THE MOVEMENT OF THE WARM FRONT THROUGH
THE DAY.
THIS EVENING...SURFACE TROUGH/WARM FRONT IS PROGGED TO SETTLE
ACROSS CENTRAL/NORTHERN IOWA INTO NORTHERN ILLINOIS THOUGH THERE
ARE NOTABLE DIFFERENCES AT THIS POINT AS TO EXACTLY HOW FAR NORTH.
VERY STRONG INSTABILITY IS EXPECTED TO DEVELOP SOUTH OF THE FRONT
WITH THUNDERSTORMS EXPECTED TO REDEVELOP/RESTRENGTHEN ACROSS IOWA
AFTERNOON INTO THE EVENING AS ANOTHER SHEARED VORT LOBE TRAVERSES
ACROSS THE REGION AND RIGHT ENTRANCE REGION TO THE LOW LEVEL JET
PROVIDES ADDITIONAL SYNOPTIC SCALE ASCENT. ASSUMING ATMOSPHERE
EFFECTIVELY RECOVERS FROM MORNING CONVECTION...FAVORABLE
SHEAR/INSTABILITY PROFILES...IMPRESSIVE CYCLONICALLY CURVED
HODOGRAPHS AND WHAT SHOULD BE SUFFICIENT FORCING TO OVERCOME ANY
CAPPING INVERSION WILL RESULT IN STRONG TO SEVERE THUNDERSTORMS
DEVELOPING WEST OF THE CWA...POSSIBLY IN A DISCRETE/SUPERCELL MODE
INITIALLY WITH THE FULL GAMUT OF SEVERE WEATHER POSSIBLE.
STRENGTHENING NOCTURNAL LOW LEVEL JET INTO THE EVENING WILL RESULT
IN STORMS MERGING INTO AN MCS AND PUSHING EAST INTO THE LOCAL
FORECAST AREA. AS THIS OCCURS...EXPECT THE PRIMARY SEVERE THREAT
TO CHANGE TO MORE OF A STRAIGHT LINE WIND DAMAGE AND FLOODING
THREAT. CORFIDI VECTORS DROP OFF TO AROUND 5 KT OR SO ON THE
SOUTHERN FLANK OF THE STORMS SO BACKBUILDING AND TRAINING
THUNDERSTORMS REMAIN A CONCERN. A FLASH FLOOD WATCH WAS ISSUED
YESTERDAY AND OPTED TO EXPAND NORTHWARD GIVEN THE TRENDS FROM THE
GFS/NAM...ALTHOUGH CONFIDENCE IS ADMITTEDLY A BIT LOWER ACROSS THE
NORTHERN TIER OF COUNTIES.
DEUBELBEISS
&&
.LONG TERM...
340 AM CDT
THURSDAY THROUGH TUESDAY...
THE UPPER LEVEL ZONAL FLOW FINALLY SHIFTS EAST LATE THIS WEEK AS AN
UPPER LEVEL TROUGH MOVES OVER THE REGION FRIDAY NIGHT. THE TROUGH
AXIS SHIFTS EAST SATURDAY WITH NORTHWEST FLOW SUNDAY. ANOTHER WEAKER
TROUGH IS POSSIBLE EARLY NEXT WEEK.
A SFC LOW WILL BE OVER NORTHERN IL AND NORTHWEST IN THURSDAY MORNING
AS A DYING MCS SLOWLY SHIFTS EAST. RAISED QPF AMOUNTS THURSDAY
MORNING AS THE DYING MCS SHOULD PRODUCE AT LEAST ANOTHER 0.35-0.5
INCHES OF RAIN SOUTH OF I-88. GUIDANCE DIFFERS ON HOW QUICKLY THE
MCS WILL EXIT THE REGION...BUT HAVE HIGH CONFIDENCE IN DRY
CONDITIONS THURSDAY NIGHT.
SADLY THERE IS A VERY SMALL BREAK BEFORE THE NEXT LOW PRESSURE
BRINGS MORE RAIN AND STORMS TO AREAS SOUTH OF I-80 FRIDAY. THE NEXT
LOW FORMS OVER THE SOUTHERN PLAINS THURSDAY NIGHT. IT THEN PASSES
OVER THE MID MISSISSIPPI VALLEY AND ALONG THE OHIO RIVER THROUGH
SATURDAY NIGHT. IT LOOKS LIKE THE MAJORITY OF PRECIP WILL FALL OVER
CENTRAL AND SOUTHERN IL...BUT KEPT A SLIGHT CHANCE TO CHANCE OF
THUNDERSTORMS SOUTH OF I-88. WE FINALLY SEE A DRY SPELL LATE THIS
WEEK AS THE LOW SHIFTS EAST AND HIGH PRESSURE SPREADS OVERHEAD.
THE NEXT CHANCE OF RAIN AND STORMS ARRIVES EARLY NEXT WEEK AS AN
UPPER LEVEL TROUGH SWINGS THROUGH. GUIDANCE DIFFERS ON HOW STRONG
THE TROUGH WILL BE AND HOW FAR SOUTH IT WILL TRAVEL...BUT HAVE
ENOUGH CONFIDENCE TO KEEP A CHANCE OF PRECIP IN THE FORECAST. WE
COULD SEE MULTIPLE VORTICITY STREAMERS SWING THROUGH AS THE TROUGH
SITS OVERHEAD SO KEPT A CHANCE OF PRECIP FROM SUNDAY NIGHT THROUGH
TUESDAY. DESPITE THE CONSTANT CHANCE OF RAIN...ONLY EXPECTING
PERIODS OF SHOWERS AND STORMS AT THIS POINT AND NOT COMPLETE
RAIN OUTS.
FOR TEMPS...THURSDAY LOOKS LIKE THE WARMEST DAY WITH HIGHS IN THE
UPPER 70S TO LOW 80S. LAKE COOLING WILL KEEP LAKEFRONT LOCATIONS IN
THE LOW 70S. COOLER AIR SINKS SOUTH THURSDAY NIGHT LEADING TO HIGH
TEMPS FRIDAY IN THE 70S WITH 60S ALONG THE LAKE. A SLOW WARM UP IS
EXPECTED WITH HIGHS BACK IN THE LOW 80S TUESDAY.
JEE
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 18Z...
* CHANCE OF LAKE BREEZE DEVELOPMENT LATE THIS AFTERNOON.
* THUNDERSTORMS LIKELY OVERNIGHT TONIGHT...MVFR-IFR CIGS/VIS
LIKELY.
KREIN
//DISCUSSION...UPDATED 18Z...
AT THE SURFACE...A LARGE AREA OF HIGH PRESSURE IS CENTERED ALONG
THE IN/OH BORDER AS A MID LEVEL IMPULSE CROSSING THE MIDDLE
MISSISSIPPI VALLEY IS BRINGING AN AREA OF SHOWERS AND
THUNDERSTORMS FROM IOWA THROUGH CENTRAL IL TO CENTRAL IN. BASED
ON THE LATEST RADAR TRENDS...EXPECT THAT ANY PCPN AND TS SHOULD
REMAIN SOUTH OF OF THE TERMINALS EARLY THIS EVENING...THROUGH IT
COULD CLIP THE SOUTHERN PORTIONS OF THE C90 TRACON AREA. AS THE
CENTER OF THE HIGH CONTINUES TO SHIFT TO THE EAST...WINDS HAVE
BECOME SSWLY AND ARE INCREASING TO ARND 10KT. LATEST RADAR IMAGERY
AND COASTAL OBSERVATIONS SHOW A LAKE BREEZE MOVING ONSHORE NEAR
KUGN...BUT THERE IS LITTLE WESTWARD PROGRESSION AND DO NOT EXPECT
THAT THE BOUNDARY WILL REACH AS FAR WEST AS ORD/MDW.
RATHER...EXPECT THAT WINDS WILL GRADUALLY BACK TO MORE SELY
THROUGH THE AFTERNOON AND INTO THE EVENING IN RESPONSE TO THE
LARGER SCALE PRESSURE PATTERN WITH THE HIGH MOVING OFF TO THE EAST
AND LOW PRESSURE DEVELOPING OVER THE CNTRL PLAINS.
THE OTHER CONCERN FOR THE PERIOD WILL BE TIMING THE NEXT ROUND OF
THUNDERSTORMS TO IMPACT THE REGION. WHILE THE ONGOING PCPN SHOULD
REMAIN SOUTH OF THE TERMINALS...CONFIDENCE IS HIGHER THAT ANOTHER
ROUND OF THUNDERSTORMS WILL DEVELOP TONIGHT OVER THE CNTRL
PLAINS/IOWA AND THEN TRACK EASTWARD. LATEST GUIDANCE IS A LITTLE
FASTER THAN PREVIOUS MODEL RUNS AND SUGGESTS THAT TS COULD REACH
RFD BY ARND 03Z...AND THEN QUICKLY PUSHING TO THE EAST ACROSS THE
CHICAGO AREA TERMINALS. WHILE CONFIDENCE IS RELATIVELY HIGH IN TS
IMPACTING THE TERMINALS OVERNIGHT TONIGHT...TIMING AND DURATION IS
A LITTLE LOWER. ALSO...AS THE MAIN SFC LOW TRACKS ALONG A
DEVELOPING WARM FRONT EXPECTED TO SET THROUGH CNTRL OR NRN IL/IN
AND WITH UPPER LEVEL FLOW SETTING UP TO BE PARALLEL TO THE SFC
FRONT...AN EXTENDED PERIOD OF TSRA IMPACTING THE TERMINALS IS
QUITE POSSIBLE OVERNIGHT AND POSSIBLY EVEN INTO TOMORROW MORNING.
KREIN
//ORD AND MDW CONFIDENCE...UPDATED 18Z...
* MEDIUM TO HIGH CONFIDENCE IN GENERAL WIND TRENDS.
* MEDIUM CONFIDENCE IN LAKE BREEZE DETAILS...AND THAT THE LAKE
BREEZE BOUNDARY WILL REMAIN EAST OF THE TERMINALS.
* MEDIUM TO HIGH CONFIDENCE IN TS IMPACTING THE TERMINALS THIS
EVENING AND TONIGHT...LOWER CONFIDENCE IN EXACT TIMING AND
DURATION.
* MEDIUM CONFIDENCE IN A PERIOD OF MVFR-IFR CIGS/VIS WITH THE
TSRA/PCPN OVERNIGHT TONIGHT AND INTO TOMORROW MORNING.
KREIN
//OUTLOOK FOR ORD/MDW FOR 00Z FRIDAY-12Z WEDNESDAY...UPDATED 12Z...
THURSDAY NIGHT...VFR. WX NIL. NELY WINDS.
FRIDAY...VFR. WX NIL. NELY WINDS.
SATURDAY...VFR. WX NIL. NELY WINDS BACKING NWLY LATE.
SUNDAY...CHANCE TSRA. MVFR POSSIBLE. NWLY WINDS BACKING SWLY.
MONDAY...CHANCE TSRA. MVFR POSSIBLE. SWLY WINDS VEERING NWLY
TUESDAY...SLIGHT CHANCE TSRA. VRBL WINDS.
KREIN
&&
.MARINE...
410 AM CDT
HIGH PRESSURE IS OVER THE REGION WITH LIGHT SOUTHWEST WINDS. WINDS
REMAIN LIGHT AND BECOME EAST THURSDAY MORNING AS A LOW PRESSURE
SYSTEM MOVES OVER THE SOUTHERN END OF THE LAKE. GUIDANCE DIFFERS ON
HOW STRONG THE LOW WILL BE SO WIND SPEEDS COULD BE STRONGER OVER THE
SOUTHERN END OF THE LAKE IF THE LOW IS STRONGER. THE LOW SHIFTS
EAST AND ANOTHER LOW PASSES WELL SOUTH OF THE LAKE OVER THE OHIO
RIVER LATE THIS WEEK. PERSISTENT NORTH TO NORTHEAST WINDS AT 20KT OR
LESS ARE EXPECTED THROUGH SATURDAY NIGHT. HIGH PRESSURE SPREADS
SOUTH OF THE LAKE WHILE A LOW SPREADS OVER THE LAKE SUNDAY NIGHT
WITH WINDS BCMG SOUTH SUNDAY EVENING AND REMAINING SOUTH TO
SOUTHWEST THROUGH MONDAY NIGHT.
JEE
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...FLASH FLOOD WATCH...ILZ003-ILZ004-ILZ005-ILZ006-ILZ008-ILZ010-
ILZ011-ILZ012-ILZ013-ILZ014-ILZ019-ILZ020-ILZ021-ILZ022-
ILZ023-ILZ032-ILZ033-ILZ039...7 PM WEDNESDAY TO 1 PM
THURSDAY.
IN...FLASH FLOOD WATCH...INZ001-INZ002-INZ010-INZ011-INZ019...7 PM
WEDNESDAY TO 1 PM THURSDAY.
LM...NONE.
&&
$$
VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
WWW.FACEBOOK.COM/NWSCHICAGO
WWW.TWITTER.COM/NWSCHICAGO
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AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
1218 PM CDT WED JUN 24 2015
.UPDATE...
1217 PM CDT
ALL INDICATIONS THIS MORNING CONTINUE TO POINT TO A CLASSIC TYPE
HEAVY RAIN EVENT ACROSS THE AREA. THE THREAT OF SEVERE THUNDERSTORMS
IS ALSO DECENT WITH THIS ACTIVITY AS WELL LATER THIS EVENING...AND
THIS PRIMARILY LOOKS TO BE IN THE FORM OF STRONG STRAIGHT LINE WINDS.
SHOWERS...WITH SOME EMBEDDED THUNDERSTORMS CONTINUE TO WEAKEN OVER
CENTRAL ILLINOIS AS THEY MOVE AWAY FROM THE BETTER FOCUS OF LAST
NIGHTS LOW LEVEL JET. SATELLITE IMAGERY CONTINUES TO INDICATE CLOUD
TOPS WARMING WITH THIS ACTIVITY...AND EVEN INDICATES SOME BREAKS IN
THE CLOUDS OVER FAR NORTHERN ILLINOIS. FARTHER WEST...HOWEVER...AN
AREA OF CONVECTION OVER EASTERN NE AND NEAR FAR WESTERN IOWA
CONTINUES TO MAINTAIN ITSELF. IT IS CERTAINLY POSSIBLE THAT THIS
ACTIVITY COULD CONTINUE TO MOVE EAST OVER IOWA INTO THIS
AFTERNOON...THEN SHIFT MORE SOUTHEAST ALONG THE MLCAPE GRADIENT. THIS
ACTIVITY...SHOULD IT MAINTAIN ITSELF THOUGH THE DAY...WOULD LIKELY
MISS MOST OF MY AREA...POSSIBLY ONLY IMPACTING MY SOUTHWESTERN
COUNTIES. SOME OF THE LATEST HRRR SOLUTIONS ARE IN LINE WITH THIS
THINKING.
OTHERWISE...THE FOCUS CONTINUES TO CENTER ON THIS EVENING THROUGH
THE OVERNIGHT FOR THE POTENTIAL OF VERY HEAVY RAIN AND FLASH
FLOODING. IT IS STILL ANTICIPATED THAT RENEWED CONVECTION WILL
DEVELOP LATER THIS AFTERNOON/EARLY THIS EVENING OVER PORTIONS OF
EASTERN IOWA INTO NORTHWESTERN ILLINOIS ALONG AND ON THE COOL SIDE
OF A NORTHWARD MOVING WARM FRONTAL BOUNDARY. THIS ACTIVITY WOULD
THEN LIKELY CONTINUE TO GROW UPSCALE AS RENEWED DEVELOPMENT
CONTINUES UPSTREAM THANKS TO A PERSISTENT SOUTHWESTERLY 40+ KT LOW
LEVEL JET CONTINUALLY REPLENISHING THE DEEP MOISTURE. THESE STORMS
WILL OCCUR WITHIN AROUND A 2 INCH PRECIPITABLE WATER
ENVIRONMENT...SO EXTREMELY HEAVY RAIN RATES WILL BE A HIGH CONCERN.
ALSO...WITH CONTINUAL UPSTREAM DEVELOPMENT LOOKING LIKELY...TRAINING
AND BACKBULDING OF CELLS COULD RESULT IN PROLONGED PERIODS OF THESE
VERY HEAVY RAIN RATES OCCURRING OVER THE SAME AREAS. AS SUCH...SOME
ISOLATED AREAS OVER THE AREA COULD EXPERIENCE 4-5+ INCH AMOUNTS OF
RAIN BEFORE THIS ACTIVITY ABATES LATER TONIGHT OR EARLY THURSDAY
MORNING. THERE ARE STILL SOME UNCERTAINTIES ON WHERE EXACTLY THE
HEAVIEST RAINFALL AMOUNTS WILL FALL. HOWEVER...WITH THE ACTIVITY
LIKELY TO MOVE EAST-SOUTHEAST WITH TIME...IT WOULD APPEAR THAT AREAS
ALONG AND SOUTH OF INTERSTATE 88 WOULD LIKELY STAND THE BEST
POTENTIAL TO EXPERIENCE RAINFALL AMOUNTS IN EXCESS OF 1 TO 2 INCHES.
WITHIN THESE TRAINING THUNDERSTORMS...THE KINEMATIC FIELDS OVER THE
AREA WILL ALSO LIKELY SUPPORT FORWARD PROPAGATING EAST-SOUTHEASTWARD
MOVING BOWING SEGMENTS OVER THE AREA. THEREFORE...STRONG DAMAGING
WINDS...PERHAPS IN EXCESS OF 70 MPH...WILL ALSO BE A THREAT WITH
THESE STORMS. A TORNADO OR TWO CAN ALSO NOT BE RULED OUT. HOWEVER...
THIS THREAT APPEARS TO BE THE HIGHEST OVER MY SOUTHEASTERN CWA THIS
EVENING IN CLOSER PROXIMATELY TO THE APPROACHING WARM FRONTAL
BOUNDARY.
KJB
&&
.SHORT TERM...
320 AM CDT
THROUGH WEDNESDAY NIGHT...
STRONG TO SEVERE THUNDERSTORMS COMPRISE THE PRIMARY FORECAST
CONCERNS FOR TODAY AND TONIGHT.
EARLY THIS MORNING...SURFACE HIGH PRESSURE IS CENTERED ACROSS
CENTRAL ILLINOIS PROVIDING MOSTLY CLEAR SKIES AND LIGHT WINDS
ACROSS NORTHERN ILLINOIS AND NORTHWEST INDIANA. FARTHER WEST...A
SURFACE TROUGH IS ANALYZED FROM NORTHERN KANSAS NE ACROSS THE MID-
MISSOURI VALLEY INTO CENTRAL IOWA. WATER VAPOR IMAGERY SHOWS A
SUBTLE/SHEARED WAVE EMBEDDED WITHIN THE MAINLY ZONAL FLOW ALOFT
MOVING ACROSS NORTHERN IOWA WHERE NOCTURNAL THUNDERSTORMS HAVE
DEVELOPED MAINLY FOCUSED ACROSS THE I-80 CORRIDOR IN IOWA. NAM/GFS
INITIALIZE ON THIS AREA OF THUNDERSTORMS AND KEEPS THE FORCING
FOCUSED TO THE WEST OF THE FORECAST AREA THROUGH MOST OF THE DAY
TODAY...ALONG WITH THE INSTABILITY. CANT RULE OUT SOME DECAYING
ELEVATED CONVECTION PROPAGATING INTO THE FORECAST AREA LATER
TODAY...HOWEVER EXPECT MOST OF THE CWA TO BE DRY THIS MORNING INTO
AT LEAST EARLY EVENING. WILL HAVE TO KEEP AN EYE ON HOW EARLY
MORNING CONVECTION IMPACTS THE MOVEMENT OF THE WARM FRONT THROUGH
THE DAY.
THIS EVENING...SURFACE TROUGH/WARM FRONT IS PROGGED TO SETTLE
ACROSS CENTRAL/NORTHERN IOWA INTO NORTHERN ILLINOIS THOUGH THERE
ARE NOTABLE DIFFERENCES AT THIS POINT AS TO EXACTLY HOW FAR NORTH.
VERY STRONG INSTABILITY IS EXPECTED TO DEVELOP SOUTH OF THE FRONT
WITH THUNDERSTORMS EXPECTED TO REDEVELOP/RESTRENGTHEN ACROSS IOWA
AFTERNOON INTO THE EVENING AS ANOTHER SHEARED VORT LOBE TRAVERSES
ACROSS THE REGION AND RIGHT ENTRANCE REGION TO THE LOW LEVEL JET
PROVIDES ADDITIONAL SYNOPTIC SCALE ASCENT. ASSUMING ATMOSPHERE
EFFECTIVELY RECOVERS FROM MORNING CONVECTION...FAVORABLE
SHEAR/INSTABILITY PROFILES...IMPRESSIVE CYCLONICALLY CURVED
HODOGRAPHS AND WHAT SHOULD BE SUFFICIENT FORCING TO OVERCOME ANY
CAPPING INVERSION WILL RESULT IN STRONG TO SEVERE THUNDERSTORMS
DEVELOPING WEST OF THE CWA...POSSIBLY IN A DISCRETE/SUPERCELL MODE
INITIALLY WITH THE FULL GAMUT OF SEVERE WEATHER POSSIBLE.
STRENGTHENING NOCTURNAL LOW LEVEL JET INTO THE EVENING WILL RESULT
IN STORMS MERGING INTO AN MCS AND PUSHING EAST INTO THE LOCAL
FORECAST AREA. AS THIS OCCURS...EXPECT THE PRIMARY SEVERE THREAT
TO CHANGE TO MORE OF A STRAIGHT LINE WIND DAMAGE AND FLOODING
THREAT. CORFIDI VECTORS DROP OFF TO AROUND 5 KT OR SO ON THE
SOUTHERN FLANK OF THE STORMS SO BACKBUILDING AND TRAINING
THUNDERSTORMS REMAIN A CONCERN. A FLASH FLOOD WATCH WAS ISSUED
YESTERDAY AND OPTED TO EXPAND NORTHWARD GIVEN THE TRENDS FROM THE
GFS/NAM...ALTHOUGH CONFIDENCE IS ADMITTEDLY A BIT LOWER ACROSS THE
NORTHERN TIER OF COUNTIES.
DEUBELBEISS
&&
.LONG TERM...
340 AM CDT
THURSDAY THROUGH TUESDAY...
THE UPPER LEVEL ZONAL FLOW FINALLY SHIFTS EAST LATE THIS WEEK AS AN
UPPER LEVEL TROUGH MOVES OVER THE REGION FRIDAY NIGHT. THE TROUGH
AXIS SHIFTS EAST SATURDAY WITH NORTHWEST FLOW SUNDAY. ANOTHER WEAKER
TROUGH IS POSSIBLE EARLY NEXT WEEK.
A SFC LOW WILL BE OVER NORTHERN IL AND NORTHWEST IN THURSDAY MORNING
AS A DYING MCS SLOWLY SHIFTS EAST. RAISED QPF AMOUNTS THURSDAY
MORNING AS THE DYING MCS SHOULD PRODUCE AT LEAST ANOTHER 0.35-0.5
INCHES OF RAIN SOUTH OF I-88. GUIDANCE DIFFERS ON HOW QUICKLY THE
MCS WILL EXIT THE REGION...BUT HAVE HIGH CONFIDENCE IN DRY
CONDITIONS THURSDAY NIGHT.
SADLY THERE IS A VERY SMALL BREAK BEFORE THE NEXT LOW PRESSURE
BRINGS MORE RAIN AND STORMS TO AREAS SOUTH OF I-80 FRIDAY. THE NEXT
LOW FORMS OVER THE SOUTHERN PLAINS THURSDAY NIGHT. IT THEN PASSES
OVER THE MID MISSISSIPPI VALLEY AND ALONG THE OHIO RIVER THROUGH
SATURDAY NIGHT. IT LOOKS LIKE THE MAJORITY OF PRECIP WILL FALL OVER
CENTRAL AND SOUTHERN IL...BUT KEPT A SLIGHT CHANCE TO CHANCE OF
THUNDERSTORMS SOUTH OF I-88. WE FINALLY SEE A DRY SPELL LATE THIS
WEEK AS THE LOW SHIFTS EAST AND HIGH PRESSURE SPREADS OVERHEAD.
THE NEXT CHANCE OF RAIN AND STORMS ARRIVES EARLY NEXT WEEK AS AN
UPPER LEVEL TROUGH SWINGS THROUGH. GUIDANCE DIFFERS ON HOW STRONG
THE TROUGH WILL BE AND HOW FAR SOUTH IT WILL TRAVEL...BUT HAVE
ENOUGH CONFIDENCE TO KEEP A CHANCE OF PRECIP IN THE FORECAST. WE
COULD SEE MULTIPLE VORTICITY STREAMERS SWING THROUGH AS THE TROUGH
SITS OVERHEAD SO KEPT A CHANCE OF PRECIP FROM SUNDAY NIGHT THROUGH
TUESDAY. DESPITE THE CONSTANT CHANCE OF RAIN...ONLY EXPECTING
PERIODS OF SHOWERS AND STORMS AT THIS POINT AND NOT COMPLETE
RAIN OUTS.
FOR TEMPS...THURSDAY LOOKS LIKE THE WARMEST DAY WITH HIGHS IN THE
UPPER 70S TO LOW 80S. LAKE COOLING WILL KEEP LAKEFRONT LOCATIONS IN
THE LOW 70S. COOLER AIR SINKS SOUTH THURSDAY NIGHT LEADING TO HIGH
TEMPS FRIDAY IN THE 70S WITH 60S ALONG THE LAKE. A SLOW WARM UP IS
EXPECTED WITH HIGHS BACK IN THE LOW 80S TUESDAY.
JEE
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 16Z...
* CHANCE OF LAKE BREEZE DEVELOPMENT LATE THIS AFTERNOON.
* THUNDERSTORMS LIKELY OVERNIGHT TONIGHT.
KREIN
//DISCUSSION...UPDATED 12Z...
AT THE SURFACE...A LARGE AREA OF HIGH PRESSURE IS CENTERED OVER
THE SOUTHERN TIP OF LAKE MICHIGAN KEEPING A VERY WEAK PRESSURE
GRADIENT OVER THE REGION. A MID LEVEL IMPULSE CROSSING THE MIDDLE
MISSISSIPPI VALLEY IS BRINGING AN AREA OF SHOWERS AND
THUNDERSTORMS TO SERN IOWA AND INTO CENTRAL ILLINOIS. BASED ON THE
LATEST RADAR TRENDS...EXPECT THAT ANY PCPN AND TS SHOULD REMAIN
SOUTH OF OF THE TERMINALS THIS MORNING...THROUGH IT COULD CLIP THE
SOUTHERN PORTIONS OF THE C90 TRACON AREA. AS THE CENTER OF THE
HIGH SHIFT TO THE EAST TODAY...WINDS SHOULD BACK FROM SSWLY TO
SELY THROUGH THE DAY. BY THIS AFTERNOON...WINDS ALOFT SHOULD BE
LESS THAN 10KT WHILE SFC WINDS ALSO REMAIN LESS THAN 10KT...SO
THERE IS A CHANCE FOR A LAKE BREEZE TO FORM. CONFIDENCE IS LOWER
ON WHETHER THE LAKE BREEZE WILL PUSH FAR ENOUGH INLAND TO REACH
ORD/MDW...AND WHETHER WINDS WILL BACK FURTHER FROM SELY TO ELY. AT
THIS POINT...CONFIDENCE IS LOW ON THE LAKE BREEZE REACHING ORD/MDW
WITH WINDS SYNOPTICALLY SETTING UP SELY THIS AFTERNOON.
THE OTHER CONCERN FOR THE PERIOD WILL BE TIMING THE NEXT ROUND OF
THUNDERSTORMS TO IMPACT THE REGION. WHILE THE ONGOING PCPN SHOULD
REMAIN SOUTH OF THE TERMINALS...CONFIDENCE IS HIGHER THAT ANOTHER
ROUND OF THUNDERSTORMS WILL DEVELOP TONIGHT OVER THE CNTRL
PLAINS/IOWA AND THEN TRACK EASTWARD AS A STRONG LINE OF
THUNDERSTORMS. LATEST GUIDANCE SUGGESTS THAT TS COULD REACH RFD
ARND 06Z...AND THEN QUICKLY PUSHING TO THE EAST ACROSS THE CHICAGO
AREA TERMINALS. WHILE CONFIDENCE IS RELATIVELY HIGH IN TS
IMPACTING THE TERMINALS OVERNIGHT TONIGHT...TIMING AND DURATION IS
A LITTLE LOWER AND THERE IS A CHANCE THAT TS COULD REACH THE
TERMINALS A LITTLE EARLIER THAN CURRENTLY INDICATED IN THE TAFS.
KREIN
//ORD AND MDW CONFIDENCE...UPDATED 16Z...
* MEDIUM TO HIGH CONFIDENCE IN GENERAL WIND TRENDS.
* LOW TO MEDIUM CONFIDENCE IN LAKE BREEZE DETAILS AND WHETHER THE
LAKE BREEZE WILL REACH ORD/MDW.
* MEDIUM TO HIGH CONFIDENCE IN TS IMPACTING THE TERMINALS THIS
EVENING AND TONIGHT...LOWER CONFIDENCE IN EXACT TIMING...
DURATION AND IMPACTS.
KREIN
//OUTLOOK FOR ORD/MDW FOR 00Z FRIDAY-12Z WEDNESDAY...UPDATED 12Z...
THURSDAY NIGHT...VFR. WX NIL. NELY WINDS.
FRIDAY...VFR. WX NIL. NELY WINDS.
SATURDAY...VFR. WX NIL. NELY WINDS BACKING NWLY LATE.
SUNDAY...CHANCE TSRA. MVFR POSSIBLE. NWLY WINDS BACKING SWLY.
MONDAY...CHANCE TSRA. MVFR POSSIBLE. SWLY WINDS VEERING NWLY
TUESDAY...SLIGHT CHANCE TSRA. VRBL WINDS.
KREIN
&&
.MARINE...
410 AM CDT
HIGH PRESSURE IS OVER THE REGION WITH LIGHT SOUTHWEST WINDS. WINDS
REMAIN LIGHT AND BECOME EAST THURSDAY MORNING AS A LOW PRESSURE
SYSTEM MOVES OVER THE SOUTHERN END OF THE LAKE. GUIDANCE DIFFERS ON
HOW STRONG THE LOW WILL BE SO WIND SPEEDS COULD BE STRONGER OVER THE
SOUTHERN END OF THE LAKE IF THE LOW IS STRONGER. THE LOW SHIFTS
EAST AND ANOTHER LOW PASSES WELL SOUTH OF THE LAKE OVER THE OHIO
RIVER LATE THIS WEEK. PERSISTENT NORTH TO NORTHEAST WINDS AT 20KT OR
LESS ARE EXPECTED THROUGH SATURDAY NIGHT. HIGH PRESSURE SPREADS
SOUTH OF THE LAKE WHILE A LOW SPREADS OVER THE LAKE SUNDAY NIGHT
WITH WINDS BCMG SOUTH SUNDAY EVENING AND REMAINING SOUTH TO
SOUTHWEST THROUGH MONDAY NIGHT.
JEE
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...FLASH FLOOD WATCH...ILZ003-ILZ004-ILZ005-ILZ006-ILZ008-ILZ010-
ILZ011-ILZ012-ILZ013-ILZ014-ILZ019-ILZ020-ILZ021-ILZ022-
ILZ023-ILZ032-ILZ033-ILZ039...7 PM WEDNESDAY TO 1 PM
THURSDAY.
IN...FLASH FLOOD WATCH...INZ001-INZ002-INZ010-INZ011-INZ019...7 PM
WEDNESDAY TO 1 PM THURSDAY.
LM...NONE.
&&
$$
VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
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AREA FORECAST DISCUSSION
NWS NORTHERN INDIANA
406 PM EDT WED JUN 24 2015
.SYNOPSIS...
ISSUED AT 400 PM EDT WED JUN 24 2015
A WARM FRONT WILL MOVE NORTH INTO THE REGION TONIGHT INTO
THURSDAY...PROVIDING THE FOCUS FOR SHOWERS AND THUNDERSTORMS.
LOCALLY HEAVY RAINFALL WILL BE THE MAIN THREAT...BUT A RISK OF
DAMAGING WINDS DOES EXIST WITH THE STRONGEST STORMS. LOWS TONIGHT
WILL BE IN THE LOWER TO MIDDLE 60S. CLOUDS AND EXPECTED RAINFALL
WILL KEEP HIGHS IN THE MIDDLE 70S TO NEAR 80.
&&
.SHORT TERM...(THIS EVENING THROUGH THURSDAY)
ISSUED AT 400 PM EDT WED JUN 24 2015
AS USUAL WITH SUMMER CONVECTION...A VERY COMPLICATED SETUP WITH
OVERNIGHT AND THURSDAY CONVECTION HIGHLY DEPENDENT ON WHAT HAPPENS
UPSTREAM TONIGHT. SEVERE WEATHER AND LOCALLY HEAVY RAINFALL THE MAIN
CONCERNS.
SEVERAL CLUSTERS OF CONVECTION ONGOING THIS AFTERNOON. WEAKENING
CONVECTION IN IL HAS STALLED NORTHWARD MOVEMENT OF WARM FRONTAL
BOUNDARY BUT CONVECTION OVER IA BEING FUELED BY STRONG MOISTURE
ADVECTION AND LOW LEVEL JET OVER SURGING BOUNDARY. EXPECT EARLY
EVENING TO BE DRY IN OUR REGION BUT FIRST FOCUS WILL BE ON DECAYING
COMPLEX FROM IA MOVING INTO OUR NORTHWEST LATER THIS EVENING. HRRR
AND RAP NOW PICKING UP ON THIS WHILE LOWER RES SPECTRAL MODELS SEEM
TO KEEP THIS SYSTEM TOGETHER AND MOVE ACROSS OUR NORTH. THINK THE
HIGHER RES GUIDANCE HAVE A GOOD HANDLE ON THIS SYSTEM AS INSTABILITY
REMAINS WEAK TO NON EXISTENT UNTIL LATER TONIGHT WHEN MUCAPES RISE
TO BETWEEN 1000 AND 1500 J/KG. 0-3 KM AND DEEPER LAYER SHEAR ALSO
INCREASE LATE WITH STRENGTHENING WEST TO SOUTHWEST LOW LEVEL JET
FUELING SECONDARY MCS DEVELOPMENT UPSTREAM. THIS SYSTEM EXPECTED TO
PROPAGATE INTO OUR WEST AND SOUTH CLOSER TO DAYBREAK. THIS WOULD BE
THE SYSTEM TO BRING FIRST ROUND OF POTENTIAL SEVERE WEATHER IN FORM
OF MAINLY DAMAGING WINDS AND HEAVY RAINFALL BUT AN ISOLATED TORNADO
COULD OCCUR GIVEN MAGNITUDE OF SHEAR AND LOW LEVEL BOUNDARY WITH
BACKED WINDS. THUS THE ENHANCED TO SLIGHT RISK OUTLOOK FOR THIS
AREA.
NEXT FOCUS WILL BE ON POSSIBILITY OF ANOTHER ROUND OF SEVERE WEATHER
AND HEAVY RAIN THURSDAY AFTERNOON ALONG SFC BOUNDARY. THIS REMAINS
HIGHLY CONDITIONAL ON WHAT HAPPENS OVERNIGHT AND HOW MUCH WE CAN
DESTABILIZE THURSDAY AFTERNOON. SOUTHERN AREAS LOOK TO BE IN THE
MOST FAVORABLE AREA AND HEAVY RAINFALL REMAINS POSSIBLE WITH PWAT
VALUES IN THE 1.25 TO 1.50 INCH RANGE. ALL OF THESE FACTORS FOR
HEAVY RAINFALL POTENTIAL WITH MULTIPLE SYSTEMS COUPLED WITH THE VERY
SATURATED GROUND AND STILL NEARLY FULL RIVERS...STREAMS AND
RESERVOIRS WARRANTED THE FLASH FLOOD WATCH IN THESE AREAS THAT
CANNOT TAKE MUCH RAINFALL.
&&
.LONG TERM...(THURSDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 400 PM EDT WED JUN 24 2015
THURSDAY NIGHT THROUGH WEDNESDAY...
WESTERLY FLOW WILL BUCKLE AND THE EASTERN TROF WILL DEEPENG
BEGINNING FRIDAY AND PERSISTING THROUGH THE REMAINDER OF THE
EXTNENDED FORECAST. WITH THE HIGH AMPLITUDE RIDGE OVER THE WESTERN
US...EXPECT TO SEE CONTINUED BELOW NORMAL TEMPERATURES...MOSTLY
CLOUDY SKIES AND CONTINUED THREAT OF SHOWERS / THUNHDERSTORMS.
BAROCLINIC DEEPENING FORECAST TO OCCUR OVER THE CENTRAL MISSISSIPPI
RIVER VALLEY FRIDAY NIGHT EJECTS INTO THE OHIO RIVER VALLEY DURING
THE DAY SATURDAY AND THIS WILL FAVOR RAINFALL OVER THE EASTERN HALF
OF THE CWA. THIS WILL BE SLOW TO MOVE OUT AS YET ANOTHER IN A SERIES
OF SHORT WAVES DIVES INTO THE REGION. THIS WILL DEEPEN THE TROF.
ALL LONG RANGE MODELS SUGGEST SEVERAL SHORTWAVES TO DROP THROUGH THE
GREAT LAKES REGION THROUGHOUT THE PERIOD...AND EACH HAS SLIGHT
TIMING AND INTENSITY DIFFERENCES. WITH THE WARM WATER TEMPERATURES
AND THE COLD FLOW OVER THE REGION...EXPECT A PROLONGED PERIOD OF
CLOUDS AND -SHRA TO CONTINUE FROM SUN-WEDNESDAY. APPEARS THAT THE
FRONTAL BOUNDARY WILL REMAIN SOUTH...OVER THE OHIO RIVER VALLEY AND
THIS WILL HELP KEEP SIGNIFICANT AND HEAVIER RAINFALL TO OUR SOUTH.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z THURSDAY AFTERNOON)
ISSUED AT 133 PM EDT WED JUN 24 2015
THUNDERSTORM CHANCES REMAIN PRIMARY CONCERN FOR AVIATION THIS
PERIOD. MID AND HIGH CLOUDS TO THIN THIS AFTERNOON BUT SHOULD SEE
VFR CONDITIONS THROUGH THE EVENING. A CONVECTIVE COMPLEX IS
EXPECTED TO MOVE THROUGH IL LATE TONIGHT AND LIKELY WILL DIVE INTO
NORTHERN INDIANA AFTER 06Z. SPREAD AMONG HIRES MODELS REMAINS HIGH
ON TRACK AND LOCATION OF STRONGEST THUNDERSTORMS. LOOKS LIKE BOTH
TAF SITES SHOULD AT LEAST SEE SOME SHOWERS WITH VICINITY THUNDER
SO CONTINUED THAT TREND WITH THIS PACKAGE UNTIL MORE DETAIL CAN BE
ADDED. IFR CIGS AND VIS POSSIBLE IF THIS SYSTEM TRACKS DIRECTLY
OVER TAF SITES WITH STRONG WIND GUSTS AND HEAVY RAIN POTENTIAL AS
WELL...MAINLY AFTER 06Z.
&&
.IWX WATCHES/WARNINGS/ADVISORIES...
IN...FLASH FLOOD WATCH FROM LATE TONIGHT THROUGH THURSDAY EVENING FOR
INZ003-012>015-020-022>027-032>034.
MI...NONE.
OH...NONE.
LM...NONE.
&&
$$
SYNOPSIS...FISHER
SHORT TERM...LASHLEY
LONG TERM...LEWIS
AVIATION...LASHLEY
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AREA FORECAST DISCUSSION
NWS DES MOINES IA
342 PM CDT WED JUN 24 2015
.SHORT TERM /TONIGHT/...
ISSUED AT 341 PM CDT WED JUN 24 2015
COMPLEX SCENARIO SETTING UP ACROSS IOWA TONIGHT WITH A
WARM FRONT SURGING NORTH-NORTHEAST INTO SOUTHWEST IOWA PROVIDING
SOME DESTABILIZATION OVER SOUTHWEST IOWA. MUCH OF THIS AREA REMAINS
CAPPED AT THE MOMENT...BUT WITH IMPRESSIVE EFFECTIVE SHEAR AND HIGH
CAPE VALUES AVAILABLE...IF STORMS DEVELOP IN THIS LOCATION THEY
LIKELY WILL RAPIDLY BECOME SEVERE THIS AFTERNOON AND EVENING.
SUPERCELLS ARE CERTAINLY POSSIBLE ON INITIATION WITH STRONG VEERING
AND DEEP LAYER SHEAR WILL PROVIDE A TORNADIC THREAT THROUGH THE MID-
EVENING HOURS.
HOWEVER...THINKING THIS AREA SHOULD REMAIN CAPPED UNTIL LLJ DEVELOPS
TONIGHT COMBINED WITH THE TIMING OF A STRONG SHORTWAVE OVER THE HIGH
PLAINS PUSH ACROSS THE STATE. EXPECTING THE WARM FRONT TO SURGE
NORTH BETWEEN THE INTERSTATE 80 TO HIGHWAY 20 CORRIDOR. STORM
REDEVELOPMENT THIS EVENING LOOKS TO BETWEEN 02Z TO 05Z THURSDAY OVER
THIS CORRIDOR FROM WEST TO EAST AND THE FRONT SHOULD LIGHT UP ALONG
THIS REGION. THE 24.19Z HRRR HAS A DECENT HANDLE ON CURRENT RADAR
TRENDS...ALTHOUGH DIMINISHES THE CURRENT CONVECTION OVER
CRAWFORD/CARROLL COUNTIES THIS AFTERNOON. POTENTIAL FOR STORMS TO
LINGER A LITTLE LONGER THAN WHAT THE HRRR SUGGESTS BUT STILL LOOKING
AT A BREAK BETWEEN REDEVELOPMENT LATER THIS EVENING. SEVERE
POTENTIAL STILL EXISTS DURING THE OVERNIGHT BUT LOOKING MORE LIKELY
STRAIGHT LINE WIND EVENT POTENTIAL.
.LONG TERM /THURSDAY THROUGH WEDNESDAY/...
ISSUED AT 341 PM CDT WED JUN 24 2015
MAIN SHORT WAVE TO TRACK SOUTHEAST OF AREA BY 12Z...BUT RESIDUAL
CONVECTION MAY LINGER OVER THE SOUTHEAST THROUGH MORNING. AS FRONT
SAGS SOUTH THURSDAY...EXPECTING A BREAK FROM THE CONVECTION THROUGH
LATE AFTERNOON. ANOTHER UPPER LEVEL SHORTWAVE WILL DROP SOUTHEAST
ACROSS THE AREA THURSDAY NIGHT AND INTO FRIDAY WITH ENOUGH LIFT AND
INSTABILITY TO PRODUCE SCT THUNDERSTORMS THROUGH THE DAY. WITH
CLOUDS ACROSS THE REGION EXPECT THAT HIGHS WILL BE HELD BACK IN THE
70S FOR ALL OF THE AREA. THE TROUGH FINALLY PULLS SOUTHEAST OF THE
REGION FRIDAY NIGHT WITH A PERIOD OF QUIET WEATHER FROM FRIDAY NIGHT
THROUGH SATURDAY EVENING. OVER THE NEXT FEW DAYS THE PATTERN WILL
SHIFT TO A NORTHWESTERLY FLOW ALOFT. THIS WILL LESSEN THE CHANCES
FOR HEAVY RAINFALL AND ALSO BRING TEMPERATURES TO NEAR NORMAL OR
SLIGHTLY BELOW NORMAL. ANOTHER NORTHERN STREAM SHORTWAVE AND COOL
FRONT WILL DROP SOUTH SATURDAY EVENING WITH ADDITIONAL SCATTERED
THUNDERSTORMS SUNDAY. HIGHS SATURDAY AND SUNDAY WILL BE SOMEWHAT
COOLER WITH NORTHWEST FLOW. HIGHS WILL REMAIN IN THE UPPER 70S TO
LOWER 80S. WITH THE NORTHWEST FLOW IN PLACE THROUGH MIDWEEK NEXT
WEEK...EXPECT MORE OF THE SAME. THE RIDGE SHOULD REMAIN WEST OF IOWA
WITH SOME CHANCES FOR SHOWERS OR THUNDERSTORMS AS COOL FRONTS DROP
SOUTH INTO THE PLAINS AND GREAT LAKES. TEMPERATURES WILL CHANGE
LITTLE WITH HIGHS IN THE 70S TO LOWER 80S AND LOWS IN THE 50S TO
60S.
&&
.AVIATION...24/18Z
ISSUED AT 115 PM CDT WED JUN 24 2015
STORM ACTIVITY WILL CONTINUE ACROSS CENTRAL TO NORTH-CENTRAL IOWA
THIS AFTERNOON INTO THE EVENING. CERTAINLY MVFR FOR CIGS AND VIS
ARE POSSIBLE AND EVEN TO IFR/LIFR CONDITIONS WITH THE HEAVY
TS...BUT LOW CONFIDENCE WITH MENTIONING IFR/LIFR CONDITIONS AS
DIFFICULT TO TIME AND LOCATE OF STORMS LATER THIS AFTERNOON. ONCE
THIS FIRST ROUND OF STORMS MOVES EAST BY 22Z...ANOTHER ROUND LOOKS
TO DEVELOP ALONG THE WARM FRONT LATER THIS EVENING. HAVE MVFR VIS
OR CIGS FOR RAIN MENTIONED BY 03Z.
&&
.HYDROLOGY...
ISSUED AT 341 PM CDT WED JUN 24 2015
WILL STILL NEED TO CONSIDER FLASH FLOODING OVERNIGHT AND HAVE
EXPANDED THE WATCH FARTHER WEST. VERY GOOD MOISTURE TRANSPORT...
WARM LAYER CLOUD DEPTHS IN THE 13-14KFT RANGE AND PRECIPITABLE
WATER VALUES WELL OVER 2 INCHES TONIGHT. FAIRLY HIGH CONFIDENCE IN
WIDESPREAD FLASH FLOODING OVER THE INTERSTATE 80 TO HIGHWAY 20
CORRIDOR. RAINFALL RATES OF 2 TO 4 INCHES PER HOUR ARE LIKELY AND
WITH THE RAIN THAT FELL ALREADY TODAY...IT WILL NOT TAKE MUCH TO
CAUSE SOME FLASH FLOODING AND POTENTIAL SIGNIFICANT FLASH
FLOODING ISSUES OVER THE AFOREMENTIONED CORRIDOR. THUS...EXPANDED
THE FLASH FLOOD WATCH FURTHER WEST AND INCREASED POPS AND QPF
CONSIDERABLY B/T 03-09Z THURSDAY.
&&
.DMX WATCHES/WARNINGS/ADVISORIES...
FLASH FLOOD WATCH THROUGH THURSDAY MORNING FOR ADAIR-APPANOOSE-
AUDUBON-BLACK HAWK-BOONE-BREMER-BUTLER-CALHOUN-CARROLL-CLARKE-
CRAWFORD-DALLAS-DAVIS-FRANKLIN-GREENE-GRUNDY-GUTHRIE-HAMILTON-
HARDIN-HUMBOLDT-JASPER-LUCAS-MADISON-MAHASKA-MARION-MARSHALL-
MONROE-POLK-POWESHIEK-SAC-STORY-TAMA-WAPELLO-WARREN-WEBSTER-
WRIGHT.
&&
$$
SHORT TERM...PODRAZIK
LONG TERM...REV
AVIATION...PODRAZIK
HYDROLOGY...PODRAZIK
AREA FORECAST DISCUSSION
NWS QUAD CITIES IA IL
322 PM CDT WED JUN 24 2015
.SYNOPSIS...
ISSUED AT 305 PM CDT WED JUN 24 2015
12Z UA ANALYSYS HAS AN 850MB WARM FRONT FROM CENTRAL
NEBRASKA...THROUGH SOUTHWEST IOWA...AND INTO SOUTHERN ILLINOIS.
ALONG AND SOUTH OF THIS FRONT WAS VERY WARM AND MOIST AIR. A WEAK
LLJ RAN FROM WEST TEXAS INTO CENTRAL KANSAS. SATELLITE/RADAR
TRENDS THROUGH MID AFTERNOON HAS A LOOSELY ORGANIZED CONVECTIVE
COMPLEX MOVING ACROSS IOWA WITH ANOTHER DEVELOPING BACK ALONG THE
MISSOURI RIVER.
18Z SFC DATA PLACES AN INFERRED LOW JUST EAST OF KOMA WITH A WARM
FRONT RUNNING FROM THE LOW TO NEAR KSTL. DEW POINTS ALONG AND
SOUTH OF THE WARM FRONT WERE IN THE UPPER 60S TO LOWER 70S. NORTH
OF THE WARM FRONT DEW POINTS WERE IN THE 50S TO LOWER 60S.
&&
.SHORT TERM...(THIS EVENING THROUGH THURSDAY)
ISSUED AT 305 PM CDT WED JUN 24 2015
RADAR AND RAP TRENDS WILL TAKE THE CURRENT CONVECTIVE COMPLEX EAST
LATE THIS AFTERNOON AND INTO THE EARLY EVENING. THE LACK OF
INSTABILITY ACROSS THE AREA MEANS THE COMPLEX WILL BE RAIN WITH
EMBEDDED THUNDERSTORMS. LOCALLY HEAVY RAINFALL WILL BE POSSIBLE
WITH THE STRONGER CONVECTION.
THERE ARE STILL QUESTIONS REGARDING THE OVERALL SEVERE THREAT FOR
LATE THIS AFTERNOON AND EVENING. THE SECONDARY CONVECTIVE COMPLEX
BACK ALONG THE MISSOURI RIVER IN WESTERN IOWA MAY POSE THE BETTER
THREAT OF SEVERE STORMS. IF SEVERE STORMS DO OCCUR LATE THIS
AFTERNOON AND EVENING...AREAS SOUTH OF I-80 WOULD BE MORE AT
THREAT.
AFTER SUNSET AND THROUGH SUNRISE THURSDAY...THE SECONDARY
CONVECTIVE COMPLEX WILL GROW UPSCALE AS FORCING AND MOISTURE
INCREASES ACROSS THE AREA. THE MODELS DO SUGGEST A SURFACE LOW
MOVING THROUGH THE CENTRAL PART OF THE AREA TONIGHT HELPING TO
ENHANCE THE RAINFALL. HEAVY RAIN IS DEFINITELY A THREAT AS STORMS
MAY MOVE REPEATEDLY OVER THE SAME AREAS.
BASED ON WHAT HAS ALREADY OCCURRED TODAY...RAINFALL OF 2 TO 4
INCHES IS PLAUSIBLE SHORTLY AFTER SUNRISE THURSDAY.
ON THURSDAY...RAIN WILL SLOWLY END FROM NORTHWEST TO SOUTHEAST
DURING THE DAY. IF CLOUDS REMAIN ACROSS THE AREA FOR MUCH OF THE
DAY...THE NORTH HALF OF THE AREA MAY BE DRY DURING THE AFTERNOON
HOURS.
.LONG TERM...(THURSDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 305 PM CDT WED JUN 24 2015
FORECAST HIGHLIGHTS OF THE LONG TERM PERIOD INCLUDE A TRANSITION TO
NORTHWEST FLOW...COOLER TEMPERATURES...AND PERIODIC RAIN CHANCES.
FOR THURSDAY NIGHT...THE FAR SOUTHERN FRINGE REMAINS IN THE MARGINAL
RISK AREA FOR SEVERE STORMS ALONG THE RESIDUAL BOUNDARY. WILL ALSO
HAVE TO MONITOR THIS AREA FOR HEAVY RAIN PER THE 12Z NAM...ALTHOUGH
THAT PARTICULAR MODEL IS THE MOST BULLISH ON QPF. ON FRIDAY...EXPECT
ADDITIONAL SCATTERED SHOWERS AND STORMS AS AN UPPER TROUGH DIPS
THROUGH THE REGION IN SHARPENING NORTHWEST FLOW. THIS FORCING WILL
EXIT QUICKLY FRIDAY NIGHT FOR A DRY PERIOD CONTINUING THROUGH
SATURDAY.
LOOKING AHEAD...ADDITIONAL SCATTERED RAIN WILL BE POSSIBLE EVERY DAY
FROM SUNDAY THROUGH WEDNESDAY. PERSISTENT NORTHWEST FLOW WILL GUIDE
PERIODIC SHORT WAVE ENERGY INTO THE FORECAST AREA. CONSENSUS BLENDED
POPS OF 20-40 PERCENT ARE REASONABLE. THE OVERALL SEVERE WEATHER
THREAT THROUGH THIS PERIOD IS LOW. SLIGHTLY BELOW NORMAL
TEMPERATURES ARE EXPECTED THROUGH THE BULK OF THE LONG TERM
PERIOD...WITH HIGHS MAINLY IN THE UPPER 70S...PERHAPS OCCASIONALLY
TOUCHING THE LOWER 80S.&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z THURSDAY AFTERNOON)
ISSUED AT 1233 PM CDT WED JUN 24 2015
CONVECTION ACROSS IOWA AND CENTRAL ILLINOIS WILL SLOWLY INCREASE
IN COVERAGE THROUGH 00Z/25 AND THEN EVOLVE INTO AN ORGANIZED
THUNDERSTORM COMPLEX AFT 00Z/25. VFR CONDITIONS ARE EXPECTED TO
CONTINUE THROUGH 00Z/25 WITH SPOTTY MVFR/IFR CONDITIONS IN
SHRA/TSRA. AFT 00Z/25 CONDITIONS WILL SLOWLY DETERIORATE TO MVFR
AS THE THUNDERSTORM COMPLEX DEVELOPS. PERIODS OF IFR CONDITIONS
ARE POSSIBLE IF A STRONGER STORM AFFECTS A TAF SITE.
&&
.HYDROLOGY...
ISSUED AT 305 PM CDT WED JUN 24 2015
ANOTHER ROUND OF HEAVY RAIN WILL BE SEEN ACROSS THE AREA FROM LATE
THIS AFTERNOON INTO THURSDAY MORNING. SOILS ACROSS THE AREA ARE
ALREADY QUITE MOIST AND THIS ADDITIONAL RAINFALL WILL QUICKLY
SATURATE THE SOILS. AREA RIVERS ARE ALREADY RUNNING HIGH FROM
HEAVY RAINFALL OVER THE PAST 10 DAYS AND SOME ARE IN FLOOD. THIS
ADDITIONAL RAIN WILL RESULT IN ADDITIONAL RISES...SOME POSSIBLY
SIGNIFICANT...ON AREA RIVERS AND INCREASE THE FLOOD THREAT.
&&
.DVN WATCHES/WARNINGS/ADVISORIES...
IA...FLASH FLOOD WATCH THROUGH THURSDAY MORNING FOR BENTON-BUCHANAN-
CEDAR-CLINTON-DELAWARE-DES MOINES-DUBUQUE-HENRY IA-IOWA-
JACKSON-JEFFERSON-JOHNSON-JONES-KEOKUK-LEE-LINN-LOUISA-
MUSCATINE-SCOTT-VAN BUREN-WASHINGTON.
IL...FLASH FLOOD WATCH THROUGH THURSDAY MORNING FOR BUREAU-CARROLL-
HANCOCK-HENDERSON-HENRY IL-JO DAVIESS-MCDONOUGH-MERCER-
PUTNAM-ROCK ISLAND-STEPHENSON-WARREN-WHITESIDE.
MO...FLASH FLOOD WATCH THROUGH THURSDAY MORNING FOR CLARK-SCOTLAND.
&&
$$
SYNOPSIS...08
SHORT TERM...08
LONG TERM...RP KINNEY
AVIATION...08
HYDROLOGY...08
AREA FORECAST DISCUSSION
NWS GOODLAND KS
225 PM MDT WED JUN 24 2015
.SHORT TERM...(THIS EVENING THROUGH THURSDAY)
ISSUED AT 206 PM MDT WED JUN 24 2015
MAIN PROBLEM IS WHERE THE FRONT CURRENTLY WAFFLING BACK AND FORTH
OVER OUR AREA IS GOING TO GO AND HOW FAST. INITIALLY THE FRONT
CAME FURTHER SOUTH FASTER THAN ANYTHING DEPICTED. THE LAST FEW
HOURS IT HAS STALLED NEAR A BURLINGTON TO GOODLAND TO OBERLIN TO
NORTON LINE. BOUNDARY IS FORECAST TO SLOWLY SAG SOUTH THROUGH
TOMORROW. MODELS...ESPECIALLY THE LARGE SCALE OUTPUT...NOT DOING
WELL WITH THE FRONT POSITION. THE RAP IS THE CLOSEST TO REALITY
RIGHT NOW.
FOR TONIGHT...700 MB TEMPERATURES ARE LESS BUT STILL NEAR PLUS 15.
SOME WEAK SHORTWAVE ENERGY IS OVER THE SOUTHEAST PORTION NEAREST
THE FRONT WITH ANOTHER SHORTWAVE TROUGH MOVING IN FROM THE WEST
DURING THE EVENING. SO GOING BY ABOVE REASONING WHICH MATCHES WHAT
THE RAP IS SHOWING...ISOLATED CONVECTION DEVELOPS ALONG AND JUST
TO THE EAST OF THE FRONTAL BOUNDARY. THIS CONVECTION GOES THROUGH
ROUGHLY MID EVENING. BELIEVE THAT THUNDERSTORMS WILL MOVE IN FROM
THE WEST MUCH LIKE LAST NIGHT. MODELS DO NOT SHOW THEM MAKING IT
VERY FAR INTO THE FORECAST AREA. THINK THAT THEY WILL MAKE FURTHER
THAN INDICATED AND THIS WILL NEED TO BE WATCHED. WENT AHEAD AND
HAVE SLIGHT CHANCE TO LOW CHANCE POPS FOR TONIGHT.
FOR THURSDAY...MODELS VERY SLOW IN MOVING THE FRONT SOUTH. NOT
SURE HOW FAR SOUTH IT WILL GO/WHERE IT WILL BE SINCE THE MODEL
OUTPUT IS SO POOR RIGHT NOW. NAM STILL DOES NOT HAVE IT THROUGH
THE AREA BY LATE TOMORROW. OTHER OUTPUT HAS IT JUST SOUTH OF THE
AREA. DO HAVE HAVE LOW LEVEL UPSLOPE BUT NOT A LOT OF FORCING IN
THE MID AND UPPER LEVELS. SINCE AM NOT SURE OF THE FINAL FRONTAL
POSITION AND THE POSSIBILITY OF A WEAK SHORTWAVE AFFECTING THE
AREA JUST HAVE SLIGHT POPS IN THE AFTERNOON AT THIS TIME.
TEMPERATURES WILL BE COOLER BUT HOW MUCH WILL BE DETERMINED BY
FRONTAL POSITION. WENT NEAR TO SLIGHTLY BELOW GUIDANCE AT THIS
TIME.
.LONG TERM...(THURSDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 225 PM MDT WED JUN 24 2015
THURSDAY NIGHT...MODELS CONTINUE TO SHOW POTENTIAL FOR THUNDERSTORM
INITIATION ALONG FRONTAL ZONE ACROSS THE SOUTHERN PART OF OUR CWA.
WITH LIMITING FORCING ALOFT I AM NOT SURE WHAT COVERAGE WILL
INITIALLY LOOK LIKE EARLY IN THE EVENING. INCREASING MOISTURE
FLUX/MODERATE INSTABILITY...AND PEAK HEIGHT FALLS/FORCING WILL OCCUR
LATER IN THE EVENING WITH SHORTWAVE TROUGH ROTATING INTO THE REGION
FROM THE NORTHERN PLAINS. THUNDERSTORM COMPLEX MAY DEVELOP OVER
NORTH CENTRAL NEBRASKA AND MOVE SOUTH INTO OUR CWA. TRACK WILL BE
DEPENDENT ON MAIN INSTABILITY AXIS/FRONT POSITION...HOWEVER THIS
SHOULD GENERALLY REMAIN ACROSS THE NORTH/NORTHEAST HALF OF THE CWA.
CONSIDERING THE VERY MOIST AIR MASS IN PLACE I COULD SEE LOCALLY
HEAVY RAINFALL...THOUGH SLOWEST STORMS WOULD BE ALONG FRONTAL ZONE
EARLY IN THE EVENING AS GUIDANCE SEEMS TO FAVOR A MORE PROGRESSIVE
FLOW LATER IN THE EVENING WHEN BETTER COVERAGE IS EXPECTED. MODERATE
INSTABILITY A GOOD EFFECTIVE SHEER WILL ALSO SUPPORT DAMAGING
WIND/SEVERE HAIL THREAT...PARTICULARLY WITH THUNDERSTORM COMPLEX
LATER IN THE EVENING.
FRIDAY-FRIDAY NIGHT...H5 RIDGE WILL BEGIN TO AMPLIFY WITH TROUGH
DEEPENING AS IT SLIDES EAST. MOISTURE ADVECTION/ LINGERING
INSTABILITY MAY ALLOW FOR FURTHER THUNDERSTORM DEVELOPMENT ALONG
FRONTAL ZONE LINGERING THROUGH FRIDAY NIGHT. LARGE SCALE FORCING
WILL BE LIMITED TO THE NORTHEAST...AND WITH SUBSIDENCE LIKELY
SPREADING INTO THE REGION FROM THE NORTHWEST FRIDAY AFTERNOON-FRIDAY
NIGHT. I KEPT POPS LIMITED TO 20...SINCE I AM NOT VERY CONFIDENT IN
MEASURABLE PRECIP DURING THESE PERIODS.
SATURDAY-WEDNESDAY...H5 RIDGE CONTINUES TO AMPLIFY OVER THE WESTERN
US WITH OMEGA BLOCK PATTERN EVENTUALLY ESTABLISHING ITSELF THROUGH
THE REMAINING EXTENDED PERIOD. THIS KEEPS AMPLIFIED NW FLOW IN PLACE
ACROSS THE PLAINS WITH PRIMARY STORM TRACK WELL OUTSIDE OF CWA.
MODELS SHOW LEE TROUGH ATTEMPTING TO REESTABLISH ITSELF WITH
SHORTWAVES ALONG THE MISSISSIPPI RIVER VALLEY OCCASIONAL KICKING
BACKDOOR FRONTS TOWARDS THE WESTERN PLAINS. TREND WILL BE TOWARDS
PRIMARILY DRY CONDITIONS AND NEAR SEASONAL HIGHS MOST PERIODS.
GUIDANCE IS SHOWING A LITTLE BIT BETTER PRECIP SIGNAL FROM THE ECMWF
WITH SHORTWAVE PASSAGE OVER OUR CWA TUESDAY AFTERNOON-TUESDAY
NIGHT...AS GFS/GEFS SHOWS LOWERING HEIGHTS ALOFT WITH RIDGE
FLATTENING SLIGHTLY. THERE ISN`T A LOT OF CONSISTENCY BETWEEN
MODELS...SO I LIMITED POPS TO 20/30. TUESDAY IS ALSO THE DAY WITH
THE LARGEST TEMP SPREAD ALOFT/AT THE SURFACE WITH GFS POSSIBLY
SUPPORTING NEAR 100F AND ECMWF CLOSER TO THE LOW/MID 90S. I KEPT MID-
UPPER 90S INHERITED FROM WEIGHTED BLEND CONSIDERING THE RANGE.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z THURSDAY AFTERNOON)
ISSUED AT 1133 AM MDT WED JUN 24 2015
VERY LOW CONFIDENCE AND UNCERTAIN FORECAST DUE TO POOR MODEL
PERFORMANCE IN THE HANDLING THE FRONT CURRENTLY OVER OUR AREA. RAP
MODEL IS THE CLOSEST BUT IT STILL IS NOT FAR ENOUGH SOUTH. USED
THE RAP FOR THE WIND FORECAST THEN BLENDED IN THE OTHER MODEL
OUTPUT THAT FITS IN WITH THE RAP SCENARIO. AT THIS TIME THINK ANY
THUNDERSTORMS WILL DEVELOP TO THE EAST AND SOUTH OF BOTH SITES.
FOR MOST OF THE PERIOD EXPECT VFR CONDITIONS. HOWEVER MVFR
CONDITIONS WILL BE POSSIBLE AFTER 06Z...ESPECIALLY WITH THE
CEILINGS.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
SHORT TERM...BULLER
LONG TERM...DR
AVIATION...BULLER
AREA FORECAST DISCUSSION
NWS GOODLAND KS
220 PM MDT WED JUN 24 2015
.SHORT TERM...(THIS EVENING THROUGH THURSDAY)
ISSUED AT 206 PM MDT WED JUN 24 2015
MAIN PROBLEM IS WHERE THE FRONT CURRENTLY WAFFLING BACK AND FORTH
OVER OUR AREA IS GOING TO GO AND HOW FAST. INITIALLY THE FRONT
CAME FURTHER SOUTH FASTER THAN ANYTHING DEPICTED. THE LAST FEW
HOURS IT HAS STALLED NEAR A BURLINGTON TO GOODLAND TO OBERLIN TO
NORTON LINE. BOUNDARY IS FORECAST TO SLOWLY SAG SOUTH THROUGH
TOMORROW. MODELS...ESPECIALLY THE LARGE SCALE OUTPUT...NOT DOING
WELL WITH THE FRONT POSITION. THE RAP IS THE CLOSEST TO REALITY
RIGHT NOW.
FOR TONIGHT...700 MB TEMPERATURES ARE LESS BUT STILL NEAR PLUS 15.
SOME WEAK SHORTWAVE ENERGY IS OVER THE SOUTHEAST PORTION NEAREST
THE FRONT WITH ANOTHER SHORTWAVE TROUGH MOVING IN FROM THE WEST
DURING THE EVENING. SO GOING BY ABOVE REASONING WHICH MATCHES WHAT
THE RAP IS SHOWING...ISOLATED CONVECTION DEVELOPS ALONG AND JUST
TO THE EAST OF THE FRONTAL BOUNDARY. THIS CONVECTION GOES THROUGH
ROUGHLY MID EVENING. BELIEVE THAT THUNDERSTORMS WILL MOVE IN FROM
THE WEST MUCH LIKE LAST NIGHT. MODELS DO NOT SHOW THEM MAKING IT
VERY FAR INTO THE FORECAST AREA. THINK THAT THEY WILL MAKE FURTHER
THAN INDICATED AND THIS WILL NEED TO BE WATCHED. WENT AHEAD AND
HAVE SLIGHT CHANCE TO LOW CHANCE POPS FOR TONIGHT.
FOR THURSDAY...MODELS VERY SLOW IN MOVING THE FRONT SOUTH. NOT
SURE HOW FAR SOUTH IT WILL GO/WHERE IT WILL BE SINCE THE MODEL
OUTPUT IS SO POOR RIGHT NOW. NAM STILL DOES NOT HAVE IT THROUGH
THE AREA BY LATE TOMORROW. OTHER OUTPUT HAS IT JUST SOUTH OF THE
AREA. DO HAVE HAVE LOW LEVEL UPSLOPE BUT NOT A LOT OF FORCING IN
THE MID AND UPPER LEVELS. SINCE AM NOT SURE OF THE FINAL FRONTAL
POSITION AND THE POSSIBILITY OF A WEAK SHORTWAVE AFFECTING THE
AREA JUST HAVE SLIGHT POPS IN THE AFTERNOON AT THIS TIME.
TEMPERATURES WILL BE COOLER BUT HOW MUCH WILL BE DETERMINED BY
FRONTAL POSITION. WENT NEAR TO SLIGHTLY BELOW GUIDANCE AT THIS
TIME.
.LONG TERM...(SATURDAY THROUGH WEDNESDAY) ISSUED AT 302 AM MDT
WED JUN 24 2015
AT THE BEGINNING OF THE EXTENDED PERIOD MODELS ARE SHOWING THE
LONGWAVE PATTERN AMPLIFYING THROUGH THE END OF THE PERIOD. A
STRONG UPPER RIDGE IS LOCATED TO OUR WEST ALONG THE ROCKIES AND
EXTENDING WELL INTO WESTERN CANADA. AT THE SAME TIME A DEEPENING
TROUGH IS LOCATED OVER THE GREAT LAKES REGION AND EXTENDING IN THE
SOUTHEASTERN U.S. THIS PATTERN SETS UP A PREDOMINANTLY
NORTHWESTERLY UPPER FLOW OVER THE TRI STATE AREA. ON THE SURFACE
THE LOCATED AREA WILL BE UNDER THE INFLUENCE OF A HIGH PRESSURE
CENTER TO THE WEST OF THE CWA.
THERE IS A SLIGHT CHANCES OF PRECIPITATION... MOSTLY IN THE FORM
OF ISOLATED AFTERNOON AND EVENING CONVECTION... ASSOCIATED WITH
THE OCCASIONAL SHORTWAVE TROUGHS THAT WILL MOVE THROUGH THE AREA
FROM THE NORTH. OTHERWISE... EXPECT A MOSTLY DRY PERIOD WITH
TEMPERATURES CLOSER TO NORMAL DUE TO THE NORTHERLY FLOW ALOFT AND
A PERSISTENT EASTERLY SURFACE WINDS.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z THURSDAY AFTERNOON)
ISSUED AT 1133 AM MDT WED JUN 24 2015
VERY LOW CONFIDENCE AND UNCERTAIN FORECAST DUE TO POOR MODEL
PERFORMANCE IN THE HANDLING THE FRONT CURRENTLY OVER OUR AREA. RAP
MODEL IS THE CLOSEST BUT IT STILL IS NOT FAR ENOUGH SOUTH. USED
THE RAP FOR THE WIND FORECAST THEN BLENDED IN THE OTHER MODEL
OUTPUT THAT FITS IN WITH THE RAP SCENARIO. AT THIS TIME THINK ANY
THUNDERSTORMS WILL DEVELOP TO THE EAST AND SOUTH OF BOTH SITES.
FOR MOST OF THE PERIOD EXPECT VFR CONDITIONS. HOWEVER MVFR
CONDITIONS WILL BE POSSIBLE AFTER 06Z...ESPECIALLY WITH THE
CEILINGS.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
SHORT TERM...BULLER
LONG TERM...BW
AVIATION...BULLER
AREA FORECAST DISCUSSION
NWS GOODLAND KS
1138 AM MDT WED JUN 24 2015
.UPDATE...
ISSUED AT 1027 AM MDT WED JUN 24 2015
COLD FRONT HAS COME MUCH FURTHER SOUTH THAN EXPECTED. COMBINATION
OF COLD OUTFLOW FROM STORMS UP NORTH AND SURFACE LOWS OVER EASTERN
COLORADO DEVELOPING DIFFERENTLY THAN WHAT THE MODELS WERE
ANTICIPATING. NOTHING IS REALLY CATCHING THIS RIGHT NOW WITH THE
RAP THE CLOSEST. HOWEVER...IT STILL IS NOT FAR ENOUGH SOUTH.
ALSO SOME WEAK THUNDERSTORM DEVELOPMENT HAS OCCURRED ALONG THE
FRONT. SO HAD TO UPDATE THE FORECAST FOR THE WINDS...COOLER
TEMPERATURES IN THE NORTHERN PORTION OF THE AREA...MORE CLOUD
COVER...AND A WIDER AREA AND SOONER INITIATION OF ISOLATED
THUNDERSTORMS THROUGH THIS EVENING. WILL PROBABLY NOT BE THE LAST
UPDATE.
&&
.SHORT TERM...(TODAY THROUGH FRIDAY NIGHT)
ISSUED AT 344 AM MDT WED JUN 24 2015
FORECAST FOCUS IS ON THE POSSIBILITY OF SEVERE THUNDERSTORMS
ACROSS THE FORECAST AREA LATE THURSDAY INTO THURSDAY NIGHT.
THE UPPER LEVEL ZONAL FLOW PATTERN ACROSS THE UNITED STATES
TRANSITIONS TO A MORE MERIDIONAL PATTERN THURSDAY AND THURSDAY
NIGHT. A RIDGE BUILDS OVER THE INTERMOUNTAIN WEST WHILE A TROUGH
DEEPENS IN THE LEE OF THE ROCKIES AND OVER THE PLAINS STATES WITH
THE PATTERN BECOMING MORE HIGHLY AMPLIFIED ON FRIDAY AND FRIDAY
NIGHT.
THE INITIAL SHORT WAVE TROUGH MOVING THROUGH THE WESTERLY FLOW
ALOFT ACROSS THE NORTHERN PLAINS TODAY LIFTS A LOW CENTER OUT OF
THE LOW PRESSURE AREA IN PLACE OVER THE FORECAST AREA. A PORTION
OF THE SURFACE LOW REMAINS ANCHORED OVER THE CENTRAL HIGH PLAINS
AND MOVES FURTHER SOUTH OVER THE PANHANDLE REGION THURSDAY AND
THURSDAY NIGHT ALONG WITH THE FRONTAL BOUNDARY AS HIGH PRESSURE
MOVES INTO THE NORTHERN SECTIONS OF THE CENTRAL HIGH PLAINS. THIS
WILL BRING SOMEWHAT COOLER TEMPERATURES TO MAINLY THE NORTHERN
SECTIONS OF THE REGION ON THURSDAY. IT WILL ALSO BRING A BETTER
CHANCE OF THUNDERSTORMS TO THE REGION LATE THURSDAY INTO THURSDAY
NIGHT. THE MARGINAL TO SLIGHT RISK OF SEVERE THUNDERSTORMS ALSO
TRANSITIONS SOUTHWARD FROM THE NORTHERN PLAINS TODAY TO THE
CENTRAL PLAINS ON THURSDAY AND THE SOUTHERN PLAIN ON FRIDAY.
COOLER MORE SEASONABLE TEMPERATURES WILL REMAIN IN PLACE THROUGH
FRIDAY AND FRIDAY NIGHT.
.LONG TERM...(SATURDAY THROUGH WEDNESDAY) ISSUED AT 302 AM MDT
WED JUN 24 2015
AT THE BEGINNING OF THE EXTENDED PERIOD MODELS ARE SHOWING THE
LONGWAVE PATTERN AMPLIFYING THROUGH THE END OF THE PERIOD. A
STRONG UPPER RIDGE IS LOCATED TO OUR WEST ALONG THE ROCKIES AND
EXTENDING WELL INTO WESTERN CANADA. AT THE SAME TIME A DEEPENING
TROUGH IS LOCATED OVER THE GREAT LAKES REGION AND EXTENDING IN THE
SOUTHEASTERN U.S. THIS PATTERN SETS UP A PREDOMINANTLY
NORTHWESTERLY UPPER FLOW OVER THE TRI STATE AREA. ON THE SURFACE
THE LOCATED AREA WILL BE UNDER THE INFLUENCE OF A HIGH PRESSURE
CENTER TO THE WEST OF THE CWA.
THERE IS A SLIGHT CHANCES OF PRECIPITATION... MOSTLY IN THE FORM
OF ISOLATED AFTERNOON AND EVENING CONVECTION... ASSOCIATED WITH
THE OCCASIONAL SHORTWAVE TROUGHS THAT WILL MOVE THROUGH THE AREA
FROM THE NORTH. OTHERWISE... EXPECT A MOSTLY DRY PERIOD WITH
TEMPERATURES CLOSER TO NORMAL DUE TO THE NORTHERLY FLOW ALOFT AND
A PERSISTENT EASTERLY SURFACE WINDS.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z THURSDAY AFTERNOON)
ISSUED AT 1133 AM MDT WED JUN 24 2015
VERY LOW CONFIDENCE AND UNCERTAIN FORECAST DUE TO POOR MODEL
PERFORMANCE IN THE HANDLING THE FRONT CURRENTLY OVER OUR AREA. RAP
MODEL IS THE CLOSEST BUT IT STILL IS NOT FAR ENOUGH SOUTH. USED
THE RAP FOR THE WIND FORECAST THEN BLENDED IN THE OTHER MODEL
OUTPUT THAT FITS IN WITH THE RAP SCENARIO. AT THIS TIME THINK ANY
THUNDERSTORMS WILL DEVELOP TO THE EAST AND SOUTH OF BOTH SITES.
FOR MOST OF THE PERIOD EXPECT VFR CONDITIONS. HOWEVER MVFR
CONDITIONS WILL BE POSSIBLE AFTER 06Z...ESPECIALLY WITH THE
CEILINGS.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
UPDATE...BULLER
SHORT TERM...LOCKHART
LONG TERM...BW
AVIATION...BULLER
AREA FORECAST DISCUSSION
NWS LAKE CHARLES LA
410 PM CDT WED JUN 24 2015
.SYNOPSIS...MOISTURE CONTINUES TO DEEPEN IN RESPONSE TO AN UPPER
LOW OVER THE SOUTHWESTERN GULF AND A PERSISTENT RIDGE OF HIGH
PRESSURE IN THE LOWER LEVELS OVER THE EASTERN GULF. THIS WILL GIVE
THE AREA A DECENT CHANCE FOR SHOWERS AND THUNDERSTORMS MAINLY
DURING THE AFTERNOON AND EVENING ON THURSDAY.
&&
.SHORT RANGE...THE HRRR DEPICTS ANOTHER IMPULSE MOVING THROUGH THE
ATCHAFALAYA IN EASTERLY FLOW AND MOVING INTO THE ACADIANA AREA
THIS EVENING BRINGING SCATTERED SHOWERS AND THUNDERSTORMS. WENT
HIGHER THAN GUIDANCE ON POPS DUE TO THIS FEATURE AS WELL AS HIGH
THETA AIR AND AMPLE MOISTURE WITH PRECIP WATER VALUES CONTINUING
ABOUT A STANDARD DEVIATION ABOVE CLIMO.
&&
.LONG RANGE...MODELS ARE STILL CONSISTENT ON A DIGGING UPPER LEVEL
TROF INTO THE MIDWEST WITH A FAIRLY DEEP LOW FOR THIS TIME OF YEAR
SOUTH OF THE GREAT LAKES. THIS WILL DRIVE A WEAK COLD FRONT INTO
OUR AREA AND BRING A LIKELY CHANCE FOR SHOWERS AND TSTMS THIS
WEEKEND. THE UPPER TROF REMAINS A FEATURE INTO NEXT WEEK OVER THE
EASTERN PORTION OF THE U.S. WHICH WILL WEAKEN THE RIDGE OVER OUR
AREA AND ALLOW FOR HIGHER THAN NORMAL RAIN CHANCES NEXT WEEK.
SWEENEY
&&
.PRELIMINARY POINT TEMPS/POPS...
AEX 73 91 77 90 / 30 40 20 30
LCH 75 90 79 88 / 30 40 10 30
LFT 77 92 77 88 / 30 40 10 30
BPT 76 90 78 89 / 30 30 10 30
&&
.LCH WATCHES/WARNINGS/ADVISORIES...
LA...NONE.
TX...NONE.
GM...NONE.
&&
$$
PUBLIC...11
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
353 PM EDT WED JUN 24 2015
.UPDATE...
ISSUED AT 1120 AM EDT WED JUN 24 2015
ONLY MINOR TWEAKS TO THE GOING FORECAST WITH THIS MORNINGS UPDATE.
A SHORTWAVE MOVING THROUGH NORTHERN MINNESOTA HAS SPREAD SOME
SHOWERS AND A FEW THUNDERSTORMS EAST-SOUTHEAST INTO WESTERN LAKE
SUPERIOR...BETWEEN THE APOSTLE ISLANDS AND ISLE ROYALE. EXPECT THIS
WAVE TO CONTINUE TO THE EAST AND SPREAD SHOWERS ACROSS THE NORTHERN
HALF OF THE KEWEENAW PENINSULA EARLY THIS AFTERNOON. THE QUESTION
FOR THIS AFTERNOON WILL BE THE AMOUNT OF SHOWER DEVELOPMENT THAT
WILL OCCUR OVER THE LAND AREAS...WHICH WILL BE AIDED BY LAKE
BREEZES. SURFACE DEWPOINTS AT THE 11AM WERE IN THE MID-UPPER
50S...BUT THE 12Z KGRB SOUNDING AND RAP ANALYSIS SOUNDINGS SHOW A
DECENT POCKET OF DRY AIR JUST ABOVE THE SURFACE AND THROUGH
800MB/7KFT. EXPECT THE SUN THAT IS OCCURRING OVER THE AREA TO AID
MIXING OF THAT DRIER AIR TO THE SURFACE OVER THE NEXT COUPLE OF
HOURS...WHICH WILL LIMIT THE INSTABILITY OVER THE AREA (DEWPOINTS
FALLING INTO THE LOWER 50S AND PROBABLY UPPER 40S TOWARDS THE
WISCONSIN BORDER). WHILE THERE WILL BE ENOUGH MOISTURE ABOVE THAT
DRY AIR TO DEVELOP CLOUDS AND LIKELY SOME SHOWERS...CONFIDENCE IS
LOWER ON WIDESPREAD SHOWERS AND HEAVIER RAIN. MODIFIED SOUNDINGS TO
EXPECTED AFTERNOON T/TD VALUES CONTINUES TO SHOW 500-600J/KG OF
MLCAPE...SO THUNDER REMAINS POSSIBLE ALONG WITH BRIEF GUSTY WINDS
DUE TO ABUNDANT LOW LEVEL DRY AIR PUSHING DCAPE VALUES OVER 800-
900J/KG OVER AT LEAST THE SOUTHERN HALF OF THE CWA. OVERALL EXPECT
THE GREATEST FOCUS OF SHOWERS TO BE OVER THE INTERIOR CENTRAL CWA
WHEN THEY DEVELOP AROUND MID AFTERNOON AND THEN MOVE TO THE
SOUTHEAST AROUND 20-25KTS.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 411 AM EDT WED JUN 24 2015
A COLD FRONT AND A SUBTLE UPPER SHORTWAVE WILL MOVE THROUGH TODAY.
THESE FEATURES AND LAKE BREEZE FORMATION WILL PROVIDE FORCING FOR
CONVECTION MAINLY INLAND FROM THE GREAT LAKES. SBCAPE VALUES SHOULD
BE IN THE 500-800J/KG RANGE INLAND...WITH RELATIVELY WEAK SHEAR DUE
TO NEARLY CALM WINDS AT AND BELOW 800MB. INVERTED V SOUNDINGS WITH
DRY LOW LEVELS AND EVEN AN INDICATION OF AN EML MAY LEAD TO SOME
GUSTY WINDS UNDER ANY COLLAPSING STORMS...BUT SEVERE IS NOT EXPECTED
AS BEST CONVECTION SHOULD BE WHERE LOW LEVEL MOISTURE IS
GREATER...AWAY FROM THE WI BORDER. CONVECTION IS STILL EXPECTED
ALONG THE WI BORDER...JUST TO A LESSER EXTENT.
NOT SURE ON EXACTLY HOW THINGS PLAY OUT TONIGHT AS A SHORTWAVE
CURRENTLY NEAR THE MT/ALBERTA BORDER MOVES INTO OR NEAR THE CWA
WHILE A SFC TROUGH MOVES THROUGH. THE NAM...GFS...GEM AND ECMWF HAVE
PRECIP MOVING ALONG WITH THESE FEATURES THROUGH THE CWA...BUT A
COUPLE OF HIGH-RES MODELS DO NOT SHOW NEARLY THE EXTENT OF PRECIP.
AT THIS TIME...SIDED WITH THE MAJORITY OF MODELS AND HAVE HIGH
CHANCE TO LIKELY POPS...BUT IS IS ENTIRELY POSSIBLE THAT SOME
LOCATIONS WILL STAY DRY TONIGHT.
.LONG TERM...(THURSDAY THROUGH TUESDAY)
ISSUED AT 426 AM EDT WED JUN 24 2015
SEVERAL PERIODS OF LIGHT SHOWERS ARE EXPECTED ACROSS UPPER MICHIGAN
DURING THE LONG TERM PERIOD...FIRST WITH LINGERING SHOWERS ON
THURSDAY FROM A PASSING SHORTWAVE...AND AGAIN DURING THE LATER PART
OF THE WEEKEND AND INTO EARLY NEXT WEEK.
THURSDAY...PASSING SHORTWAVE IN A NW FLOW COULD ALLOW SOME ISOLD TO
SCT SHOWERS TO LINGER DURING THE MORNING INTO EARLY AFTERNOON HOURS
AS MODELS GENERALLY SHOW 200-400 J/KG MLCAPE FOR INSTABILITY OVER
INLAND LOCATIONS. OTHERWISE...CONFLUENT FLOW ALOFT AHEAD OF BUILDING
RIDGE AND ASSOC MID-LVL Q-VECT DIV/SUBSIDENCE SHOULD GENERALLY LEAD
TO DRYING CONDITIONS ESPECIALLY BY LATE AFTERNOON.
TEMPORARY SPLIT-FLOW PATTERN DEVELOPING WILL ALLOW AN AREA OF SFC
HIGH PRESSURE TO DROP SOUTHEAST ACROSS THE UPPER GREAT LAKES REGION
THU NIGHT AND PERSIST INTO SATURDAY RESULTING IN MAINLY DRY
CONDITIONS. 00Z NAM HINTS AT A FEW DIURNAL SHOWERS DEVELOPING ON
FRIDAY ALONG THE LAKE BREEZES BUT FOR NOW WL MAINTAIN DRY FCST AS
MID-LVLS WILL LIKELY BE TOO DRY FOR SHRA DEVELOPMENT. OTHERWISE
SHOULD SEE PARTLY CLOUDY TO MOSTLY CLEAR SKIES OVER THE AREA.
AMPLIFICATION OF UPSTREAM RIDGE OVER THE WRN CONUS ALONG WITH A
SERIES OF WAVES DIVING SOUTH THROUGH THE NRN AND CENTRAL PLAINS LATE
THIS WEEK WILL HELP AMPLIFY THE UPPER TROUGH OVER THE EASTERN HALF
OF THE CONUS FOR THIS WEEKEND. WHILE THE TROUGH WILL WEAKEN AND
SHIFT EAST INTO EARLY NEXT WEEK...A SERIES OF SHORTWAVES DROPPING
SOUTHEAST INTO THE GREAT LAKES REGION SUNDAY INTO TUESDAY WILL
REINFORCE THE UPPER TROUGH OVER THE GREAT LAKES REGION FOR NEXT
WEEK. THIS WILL YIELD NORMAL TO BELOW NORMAL TEMPERATURES ALONG WITH
PERIODS OF RAIN SHOWERS AND MAYBE EVEN A FEW THUNDERSTORMS.
ALSO SOMETHING TO WATCH...THE LATEST 00Z RUN OF THE ECMWF SHOWS 850
MB TEMPS PLUMMETING TO AROUND 1C BY NEXT TUE EVENING (THE LAST DAY
OF JUNE)...BRRR! THIS 00Z SOLUTION IS DEFINITELY MORE AMPLIFIED
WITH THE MID-UPR TROUGH INTO THE UPPER GREAT LAKES THAN EITHER THE
00Z GFS OR THE PREVIOUS 12Z ECMWF SOLN...ALLOWING A DIRECT PATH FOR
ARCTIC AIR TO DIVE SOUTH INTO THE REGION. AGAIN THIS IS JUST ONE
MODEL RUN...BUT IT WILL BE SOMETHING TO MONITOR OVER THE NEXT
SEVERAL MODEL RUNS AS A TREND TOWARD THIS MORE AMPLIFIED AND COLDER
SOLUTION COULD RESULT IN A BRIEF SPELL OF WELL BELOW NORMAL TEMPS
FOR THE MIDDLE OF NEXT WEEK.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z THURSDAY AFTERNOON)
ISSUED AT 152 PM EDT WED JUN 24 2015
DIURNAL HEATING HAS LED TO THE DEVELOPMENT OF CLOUDS AND SHOWERS
OVER THE INTERIOR PORTIONS OF UPPER MICHIGAN...WHILE A WEAK UPPER
LEVEL DISTURBANCE MOVING EAST ACROSS THE NORTHERN HALF OF LAKE
SUPERIOR IS PRODUCING SHOWERS THERE TOO. EXPECT THE SHOWERS THAT
ARE AFFECTING KCMX TO PUSH EAST AND DIMINISH OVER THE NEXT FEW
HOURS. MEANWHILE...THE SHOWERS DEVELOPING OVER THE INTERIOR
WEST/CENTRAL U.P. WILL CONTINUE TO EXPAND IN COVERAGE AND AFFECT
KIWD/KSAW A LITTLE LATER THIS AFTERNOON. THERE IS ENOUGH
INSTABILITY FOR SOME RUMBLES OF THUNDER...BUT DIDN/T FEEL CONFIDENT
ENOUGH TO INCLUDE AT KSAW/KIWD AND WILL AMEND AS NECESSARY IF THEY
DEVELOP. FOR TONIGHT...ANOTHER DISTURBANCE WILL MOVE THROUGH THE
AREA AND IT SHOULD LEAD TO SHOWERS AT ALL THREE SITES. DEPENDING ON
THE RAIN...COULD SEE SOME PATCHY GROUND FOG DEVELOP AND HAVE
INCLUDED A BRIEF MVFR VSBY FOR KSAW DUE TO THAT. THAT DISTURBANCE
WILL SHIFT EAST OF THE AREA THROUGH THE DAY TOMORROW.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 352 PM EDT WED JUN 24 2015
THERE WAS SOME LOW CLOUDS AND FOG OVER PORTIONS OF LAKE
SUPERIOR THIS MORNING. SOME OF THAT HAS DISSIPATED AND THE NORTHERN
PORTIONS HAVE BEEN COVERED BY CLOUDS. THUS...HAVE LIMITED CONFIDENCE
ON COVERAGE AND THICKNESS.
HIGH PRESSURE DROPPING SOUTH OVER LAKE SUPERIOR TONIGHT WILL LEAD
TO WINDS STAYING BELOW 20KTS THROUGH AT LEAST SATURDAY. THEN A
SERIES OF WEAK TROUGHS WILL DROP SOUTHEAST ACROSS LAKE SUPERIOR
SUNDAY INTO EARLY NEXT WEEK...BUT WINDS ARE STILL EXPECTED TO STAY
BELOW 20KTS.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
UPDATE...SRF
SHORT TERM...TITUS
LONG TERM...VOSS
AVIATION...SRF
MARINE...SRF
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
153 PM EDT WED JUN 24 2015
.UPDATE...
ISSUED AT 1120 AM EDT WED JUN 24 2015
ONLY MINOR TWEAKS TO THE GOING FORECAST WITH THIS MORNINGS UPDATE.
A SHORTWAVE MOVING THROUGH NORTHERN MINNESOTA HAS SPREAD SOME
SHOWERS AND A FEW THUNDERSTORMS EAST-SOUTHEAST INTO WESTERN LAKE
SUPERIOR...BETWEEN THE APOSTLE ISLANDS AND ISLE ROYALE. EXPECT THIS
WAVE TO CONTINUE TO THE EAST AND SPREAD SHOWERS ACROSS THE NORTHERN
HALF OF THE KEWEENAW PENINSULA EARLY THIS AFTERNOON. THE QUESTION
FOR THIS AFTERNOON WILL BE THE AMOUNT OF SHOWER DEVELOPMENT THAT
WILL OCCUR OVER THE LAND AREAS...WHICH WILL BE AIDED BY LAKE
BREEZES. SURFACE DEWPOINTS AT THE 11AM WERE IN THE MID-UPPER
50S...BUT THE 12Z KGRB SOUNDING AND RAP ANALYSIS SOUNDINGS SHOW A
DECENT POCKET OF DRY AIR JUST ABOVE THE SURFACE AND THROUGH
800MB/7KFT. EXPECT THE SUN THAT IS OCCURRING OVER THE AREA TO AID
MIXING OF THAT DRIER AIR TO THE SURFACE OVER THE NEXT COUPLE OF
HOURS...WHICH WILL LIMIT THE INSTABILITY OVER THE AREA (DEWPOINTS
FALLING INTO THE LOWER 50S AND PROBABLY UPPER 40S TOWARDS THE
WISCONSIN BORDER). WHILE THERE WILL BE ENOUGH MOISTURE ABOVE THAT
DRY AIR TO DEVELOP CLOUDS AND LIKELY SOME SHOWERS...CONFIDENCE IS
LOWER ON WIDESPREAD SHOWERS AND HEAVIER RAIN. MODIFIED SOUNDINGS TO
EXPECTED AFTERNOON T/TD VALUES CONTINUES TO SHOW 500-600J/KG OF
MLCAPE...SO THUNDER REMAINS POSSIBLE ALONG WITH BRIEF GUSTY WINDS
DUE TO ABUNDANT LOW LEVEL DRY AIR PUSHING DCAPE VALUES OVER 800-
900J/KG OVER AT LEAST THE SOUTHERN HALF OF THE CWA. OVERALL EXPECT
THE GREATEST FOCUS OF SHOWERS TO BE OVER THE INTERIOR CENTRAL CWA
WHEN THEY DEVELOP AROUND MID AFTERNOON AND THEN MOVE TO THE
SOUTHEAST AROUND 20-25KTS.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 411 AM EDT WED JUN 24 2015
A COLD FRONT AND A SUBTLE UPPER SHORTWAVE WILL MOVE THROUGH TODAY.
THESE FEATURES AND LAKE BREEZE FORMATION WILL PROVIDE FORCING FOR
CONVECTION MAINLY INLAND FROM THE GREAT LAKES. SBCAPE VALUES SHOULD
BE IN THE 500-800J/KG RANGE INLAND...WITH RELATIVELY WEAK SHEAR DUE
TO NEARLY CALM WINDS AT AND BELOW 800MB. INVERTED V SOUNDINGS WITH
DRY LOW LEVELS AND EVEN AN INDICATION OF AN EML MAY LEAD TO SOME
GUSTY WINDS UNDER ANY COLLAPSING STORMS...BUT SEVERE IS NOT EXPECTED
AS BEST CONVECTION SHOULD BE WHERE LOW LEVEL MOISTURE IS
GREATER...AWAY FROM THE WI BORDER. CONVECTION IS STILL EXPECTED
ALONG THE WI BORDER...JUST TO A LESSER EXTENT.
NOT SURE ON EXACTLY HOW THINGS PLAY OUT TONIGHT AS A SHORTWAVE
CURRENTLY NEAR THE MT/ALBERTA BORDER MOVES INTO OR NEAR THE CWA
WHILE A SFC TROUGH MOVES THROUGH. THE NAM...GFS...GEM AND ECMWF HAVE
PRECIP MOVING ALONG WITH THESE FEATURES THROUGH THE CWA...BUT A
COUPLE OF HIGH-RES MODELS DO NOT SHOW NEARLY THE EXTENT OF PRECIP.
AT THIS TIME...SIDED WITH THE MAJORITY OF MODELS AND HAVE HIGH
CHANCE TO LIKELY POPS...BUT IS IS ENTIRELY POSSIBLE THAT SOME
LOCATIONS WILL STAY DRY TONIGHT.
.LONG TERM...(THURSDAY THROUGH TUESDAY)
ISSUED AT 426 AM EDT WED JUN 24 2015
SEVERAL PERIODS OF LIGHT SHOWERS ARE EXPECTED ACROSS UPPER MICHIGAN
DURING THE LONG TERM PERIOD...FIRST WITH LINGERING SHOWERS ON
THURSDAY FROM A PASSING SHORTWAVE...AND AGAIN DURING THE LATER PART
OF THE WEEKEND AND INTO EARLY NEXT WEEK.
THURSDAY...PASSING SHORTWAVE IN A NW FLOW COULD ALLOW SOME ISOLD TO
SCT SHOWERS TO LINGER DURING THE MORNING INTO EARLY AFTERNOON HOURS
AS MODELS GENERALLY SHOW 200-400 J/KG MLCAPE FOR INSTABILITY OVER
INLAND LOCATIONS. OTHERWISE...CONFLUENT FLOW ALOFT AHEAD OF BUILDING
RIDGE AND ASSOC MID-LVL Q-VECT DIV/SUBSIDENCE SHOULD GENERALLY LEAD
TO DRYING CONDITIONS ESPECIALLY BY LATE AFTERNOON.
TEMPORARY SPLIT-FLOW PATTERN DEVELOPING WILL ALLOW AN AREA OF SFC
HIGH PRESSURE TO DROP SOUTHEAST ACROSS THE UPPER GREAT LAKES REGION
THU NIGHT AND PERSIST INTO SATURDAY RESULTING IN MAINLY DRY
CONDITIONS. 00Z NAM HINTS AT A FEW DIURNAL SHOWERS DEVELOPING ON
FRIDAY ALONG THE LAKE BREEZES BUT FOR NOW WL MAINTAIN DRY FCST AS
MID-LVLS WILL LIKELY BE TOO DRY FOR SHRA DEVELOPMENT. OTHERWISE
SHOULD SEE PARTLY CLOUDY TO MOSTLY CLEAR SKIES OVER THE AREA.
AMPLIFICATION OF UPSTREAM RIDGE OVER THE WRN CONUS ALONG WITH A
SERIES OF WAVES DIVING SOUTH THROUGH THE NRN AND CENTRAL PLAINS LATE
THIS WEEK WILL HELP AMPLIFY THE UPPER TROUGH OVER THE EASTERN HALF
OF THE CONUS FOR THIS WEEKEND. WHILE THE TROUGH WILL WEAKEN AND
SHIFT EAST INTO EARLY NEXT WEEK...A SERIES OF SHORTWAVES DROPPING
SOUTHEAST INTO THE GREAT LAKES REGION SUNDAY INTO TUESDAY WILL
REINFORCE THE UPPER TROUGH OVER THE GREAT LAKES REGION FOR NEXT
WEEK. THIS WILL YIELD NORMAL TO BELOW NORMAL TEMPERATURES ALONG WITH
PERIODS OF RAIN SHOWERS AND MAYBE EVEN A FEW THUNDERSTORMS.
ALSO SOMETHING TO WATCH...THE LATEST 00Z RUN OF THE ECMWF SHOWS 850
MB TEMPS PLUMMETING TO AROUND 1C BY NEXT TUE EVENING (THE LAST DAY
OF JUNE)...BRRR! THIS 00Z SOLUTION IS DEFINITELY MORE AMPLIFIED
WITH THE MID-UPR TROUGH INTO THE UPPER GREAT LAKES THAN EITHER THE
00Z GFS OR THE PREVIOUS 12Z ECMWF SOLN...ALLOWING A DIRECT PATH FOR
ARCTIC AIR TO DIVE SOUTH INTO THE REGION. AGAIN THIS IS JUST ONE
MODEL RUN...BUT IT WILL BE SOMETHING TO MONITOR OVER THE NEXT
SEVERAL MODEL RUNS AS A TREND TOWARD THIS MORE AMPLIFIED AND COLDER
SOLUTION COULD RESULT IN A BRIEF SPELL OF WELL BELOW NORMAL TEMPS
FOR THE MIDDLE OF NEXT WEEK.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z THURSDAY AFTERNOON)
ISSUED AT 152 PM EDT WED JUN 24 2015
DIURNAL HEATING HAS LED TO THE DEVELOPMENT OF CLOUDS AND SHOWERS
OVER THE INTERIOR PORTIONS OF UPPER MICHIGAN...WHILE A WEAK UPPER
LEVEL DISTURBANCE MOVING EAST ACROSS THE NORTHERN HALF OF LAKE
SUPERIOR IS PRODUCING SHOWERS THERE TOO. EXPECT THE SHOWERS THAT
ARE AFFECTING KCMX TO PUSH EAST AND DIMINISH OVER THE NEXT FEW
HOURS. MEANWHILE...THE SHOWERS DEVELOPING OVER THE INTERIOR
WEST/CENTRAL U.P. WILL CONTINUE TO EXPAND IN COVERAGE AND AFFECT
KIWD/KSAW A LITTLE LATER THIS AFTERNOON. THERE IS ENOUGH
INSTABILITY FOR SOME RUMBLES OF THUNDER...BUT DIDN/T FEEL CONFIDENT
ENOUGH TO INCLUDE AT KSAW/KIWD AND WILL AMEND AS NECESSARY IF THEY
DEVELOP. FOR TONIGHT...ANOTHER DISTURBANCE WILL MOVE THROUGH THE
AREA AND IT SHOULD LEAD TO SHOWERS AT ALL THREE SITES. DEPENDING ON
THE RAIN...COULD SEE SOME PATCHY GROUND FOG DEVELOP AND HAVE
INCLUDED A BRIEF MVFR VSBY FOR KSAW DUE TO THAT. THAT DISTURBANCE
WILL SHIFT EAST OF THE AREA THROUGH THE DAY TOMORROW.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 411 AM EDT WED JUN 24 2015
WINDS WILL REMAIN BELOW 20KTS INTO THE MIDDLE OF NEXT WEEK. A LOW
PRESSURE SYSTEM DEVELOPING IN THE CENTRAL PLAINS TODAY WILL SLIDE E
THROUGH FRIDAY...WHILE ELONGATING OVER THE TENNESSEE VALLEY. A HIGH
OVER W ONTARIO THURSDAY MORNING WILL REMAIN OVER THE W GREAT LAKES
THROUGH SATURDAY. THIS RIDGE WILL SLIDE SLOWLY TO THE SE SATURDAY
NIGHT INTO SUNDAY AS A LOW SLIDES ACROSS N ONTARIO.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
UPDATE...SRF
SHORT TERM...TITUS
LONG TERM...VOSS
AVIATION...SRF
MARINE...TITUS
AREA FORECAST DISCUSSION
NWS BILLINGS MT
328 PM MDT WED JUN 24 2015
.SHORT TERM...VALID FOR THU AND FRI...
THUNDERSTORMS REMAIN THE MAIN FOCUS IN THE SHORT TERM.
THUNDERSTORM CHANCES THE REST OF TODAY HAVE SHIFTED TOWARDS BIG
HORN AND SHERIDAN COUNTIES. MUCH OF THE ENERGY WHAT WAS EXPECTED
TO BE IN THE EASTERN ZONES HAS BEEN DISSIPATED BY CONVECTION
EARLIER THIS MORNING. MUCH OF THE HI RES GUIDANCE SHOWS LIMITED
CAPE VALUES FROM CUSTER AND POWDER RIVER COUNTIES EASTWARD. ACROSS
BIG HORN AND SHERIDAN COUNTIES CAPE VALUES REACH 1000 TO 1200 J/KG
ALONG WITH SHEAR VALUES FROM 0 TO 6 KM REACHING 50 TO 60 KNOTS.
MID MORNING RUNS OF THE HRRR...ALONG WITH THE 12Z NSSL WRF...SHOWS
ACTIVITY DEVELOPING OVER THE THE SNOWY MOUNTAINS AND THEN
STRENGTHENING ACROSS BIG HORN COUNTY IN THE BETTER ENVIRONMENT.
THE CAVEAT TO THIS IS THE HIGH CLOUDS OVER MUCH OF THE AREA AND
THE LOW CLOUDS THAT HAVE HUNG AROUND IN SHERIDAN INTO EARLY
AFTERNOON. THE LATEST RUNS OF THE HRRR ARE RATHER QUIET THIS
AFTERNOON. EVEN WITH THE SHORTWAVE MOVING THROUGH THE
AREA...MODELS ARE NOT GIVING A HIGH DEGREE OF CONFIDENCE IN THE
CHANCES FOR THUNDERSTORMS. GIVEN THE SHEAR AND CAPE...AT LEAST
ACROSS PART OF THE AREA...IF STORMS CAN DEVELOP THEY HAVE THE
POTENTIAL TO BE STRONG TO SEVERE.
THE SETUP FOR THURSDAY DOES NOT LOOK AS GOOD FOR SEVERE
WEATHER...ALTHOUGH SOME STORMS STILL COULD BE STRONGER. THE AREA
WILL BEGIN TO SEE THE INFLUENCE OF THE RIDGE THAT IS BUILDING INTO
THE WESTERN US. THIS WILL RESULT IN SUBTLE RISING HEIGHTS. THIS
WILL HELP TO DECREASE RAIN CHANCES SOME. THAT SAID ANOTHER
SHORTWAVE WILL MOVE ACROSS SOUTHEASTERN MONTANA...WHICH WILL
PLACES THE BEST CHANCES FOR CONVECTION AGAIN FROM POWDER RIVER AND
CUSTER COUNTIES EAST.
FRIDAY THE AREA IS WILL UNDER THE INFLUENCE OF THE BUILDING RIDGE
AND WILL SEE RAIN CHANCES DIMINISH. TEMPERATURES WILL ALSO BEGIN
THEIR INCREASE INTO THE WEEKEND. REIMER
.LONG TERM...VALID FOR SAT...SUN...MON...TUE...WED...
VERY HOT WEATHER IS EXPECTED THIS WEEKEND AND INTO EARLY NEXT WEEK
THANKS TO A LARGE 500-MB RIDGE THAT WILL DEVELOP OVER THE WESTERN
UNITED STATES. THE MULTI-MODEL CONSENSUS THAT WE USED TO BUILD
THE FORECAST CALLS FOR HIGHS WELL INTO THE 90S F SATURDAY AND
SUNDAY...AND WE ARE STILL CALLING FOR HIGHS OF 100 F IN MANY SPOTS
ON MONDAY WHEN 700-MB TEMPERATURES PEAK AT +15 TO +18 C. THE 12
UTC GFS AND ECMWF SUGGEST THAT THE RIDGE WILL RETROGRADE A BIT
NEXT TUESDAY AND WEDNESDAY...WHICH WILL SHOULD LET HIGHS DROP BACK
A BIT INTO THE LOWER TO MIDDLE 90S F. THE FORECAST IS ESSENTIALLY
A DRY ONE AT THIS POINT SINCE MODEL OUTPUT HAS ONLY A WEAK SIGNAL
OF MONSOONAL MOISTURE REACHING THE REGION UNDERNEATH THE LARGE
RIDGE ALOFT. SCHULTZ
&&
.AVIATION...
A FEW SHOWERS AND THUNDERSTORMS ARE POSSIBLE ACROSS SOUTHERN MT
AND NORTH CENTRAL WY THROUGH TONIGHT...BUT OUR CONFIDENCE IS LOW
WITH REGARD TO THE COVERAGE OF THAT ACTIVITY. SUB-VFR CONDITIONS
ARE POSSIBLE IN ANY STORMS THAT DEVELOP...BUT VFR WEATHER WILL
OTHERWISE PREVAIL THROUGH TONIGHT. SCHULTZ
&&
.PRELIMINARY POINT TEMP/POPS...
THU FRI SAT SUN MON TUE WED
-----------------------------------------------------------
BIL 060/084 060/091 061/093 063/096 066/100 068/094 064/090
22/T 10/U 00/U 01/U 11/U 11/B 11/U
LVM 053/086 051/093 053/095 056/098 056/100 059/093 056/093
21/B 10/U 01/U 11/U 11/B 11/B 11/B
HDN 060/086 057/093 060/095 063/099 064/101 066/095 063/091
33/T 20/B 00/U 00/U 00/G 11/B 11/U
MLS 059/083 059/088 061/093 062/095 063/097 066/092 063/089
23/T 21/B 00/U 00/U 00/U 11/B 11/U
4BQ 059/081 058/086 058/090 060/093 062/095 065/092 061/088
34/T 31/B 00/U 00/U 11/U 11/B 11/U
BHK 056/080 057/084 058/089 059/089 061/091 062/086 059/084
24/T 31/B 10/U 00/U 00/U 11/B 12/T
SHR 057/080 054/085 055/088 056/091 057/093 061/091 058/086
33/T 21/B 10/U 11/U 11/U 11/B 11/B
&&
.BYZ WATCHES/WARNINGS/ADVISORIES...
MT...NONE.
WY...NONE.
&&
$$
WEATHER.GOV/BILLINGS
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
200 PM EDT WED JUN 24 2015
.SYNOPSIS...
HIGH PRESSURE WILL RESULT IN DRY WEATHER WITH INCREASING AMOUNTS
OF SUNSHINE THIS AFTERNOON. A PASSING WAVE OF LOW PRESSURE WILL
BRING SHOWERS THROUGH THE REGION LATE THURSDAY. OUR PATTERN WILL
REMAIN SLIGHTLY COOLER THAN NORMAL...AND UNSETTLED WITH PERIODIC
CHANCES OF SHOWERS THROUGH THE WEEKEND.
&&
.NEAR TERM /THROUGH TONIGHT/...
9 AM UPDATE...
VISIBLE SATELLITE IMAGERY SHOWS AN OVC LAYER OF STRATOCUMULUS
ACROSS NORTH CENTRAL NY TO THE CATSKILLS...EASTERN SOUTHERN TIER
OF NY AND SOUTH INTO THE POCONOS AND SCRANTON/WILKES BARRE AREAS
OF PA. THIS LAYER WAS BTWN 1800 AND 3000 FEET AND SLOWLY
DEVELOPING TO THE W-SW AS A LOW-LEVEL NW FLOW ASCENDS UP THE HILLS
OF C NY AND NE PA AND SATURATES OUT. THIS IS AIDED BY SOME
BOUNDARY LAYER HEATING. AS THE BNDRY LAYER HEATS AND GROWS INTO
THE AFTERNOON DRIER AIR FROM ABOVE WILL ENTRAIN DOWNWARD AND MUCH
OF THE CLOUDINESS WILL BREAK UP. MODEL SOUNDINGS FROM
NAM...GFS...RAP AND HRRR ALL SEEM TO QUICK TO MIX OUT THE OVC
LAYER. THE NAM4KM MODEL SOUNDINGS APPEAR TO HAVE THE BEST HANDLE
ON THE PRESENT SITUATION AND DELAY THE CLOUDS BREAKING UP INTO
THE AFTERNOON. SO WILL FOLLOW NAM 4KM. LOOKING AT THE CU RULE
WHICH TAKES THE 850 MB TEMP AND SUBTRACTS THE 1000 MB DWPT THE GFS...NAM
AND ECMWF SUGGEST A SCT CUMULUS LAYER THIS AFTERNOON AS THE BNDRY
LAYER REACHES ITS MAX HGHT PROBABLY ARND 5-6 KFT. SO WILL KEEP PC
SKIES BY MID AFTERNOON AS WE BELIEVE THE PRESENT OVC SC LAYER WILL
EVOLVE INTO SCT CU BY 19-20Z. ALSO ADJUSTED TEMPS DOWN A TAD TO
ACCOUNT FOR MORE CLOUD COVER. HARD TO BELIEVE IT IS LATE JUNE HERE
AT BGM AS THE SKY LOOKS VERY MUCH LIKE NOVEMBER NOW!!
4 AM UPDATE...
NORTHWEST WINDS WILL CONTINUE TO ADVECT IN A DRY AIR MASS...AS
HIGH PRESSURE SPREADS IN FROM THE MIDWEST. PLENTY OF SUNSHINE CAN
BE EXPECTED...WITH HIGHS TODAY MAINLY IN THE 70S...A FEW TO
SEVERAL DEGREES SHORT OF CLIMATOLOGY. DEWPOINTS WILL ONLY BE LOW
TO MID 50S...WHICH FOR MOST IS VERY COMFORTABLE.
QUIET CONDITIONS PERSIST TONIGHT WITH A MAINLY CLEAR SKY...THEN
INCREASING HIGH THIN CLOUDS TOWARDS DAWN AHEAD OF THE NEXT
DISTURBANCE...WITH LOWS IN THE 50S.
&&
.SHORT TERM /THURSDAY THROUGH FRIDAY NIGHT/...
4 AM UPDATE...
THURSDAY STARTS OFF FAIRLY QUIET...BUT A NORTHERN STREAM SUMMER
CLIPPER OF SORTS...WILL ARRIVE FROM THE UPPER MIDWEST MID TO LATE
AFTERNOON. MEANWHILE...SOUTHERN STREAM WARM FRONT WILL ATTEMPT TO
LIFT NORTHWARD FROM THE MIDATLANTIC STATES BUT WILL FALL SHORT.
BAROCLINIC LIFT WILL OCCUR NORTH OF THAT WARM FRONT...AS THE
NORTHERN STREAM WAVE ALSO PASSES. HOWEVER...INSTABILITY LOOKING
MORE DOUBTFUL...AND THUS EXPECTING MAINLY JUST SHOWERS OR EVEN
STRATIFORM RAIN INSTEAD OF THUNDER. I INCLUDE ONLY A SLIGHT CHANCE
OF THUNDER IN NORTHEAST PA AT THIS TIME...TO ACCOMPANY LIKELIHOOD
OF SHOWERS LATE THURSDAY INTO THURSDAY EVENING. FURTHER
NORTH...CHANCES DROP OFF...TO THE POINT THAT SOME PORTIONS OF
CENTRAL NY MAY RECEIVE VERY LITTLE RAIN FROM THIS SYSTEM.
00Z NAM APPEARS TO BE SUFFERING FROM CONVECTIVE FEEDBACK GIVEN
THE FAIR AMOUNT OF STABILITY...AND THUS ITS QPF AMOUNTS LOOK
UNREASONABLE. SOMETHING ON THE ORDER OF UP TO A FEW TENTHS OF AN
INCH...OR CONSENSUS OF NON-NAM MODELS...APPEARS MORE PROBABLE...AND
THOSE AMOUNTS FOCUSED MAINLY TWIN TIERS SOUTHWARD.
WITH TIME...EASTERN UPPER TROUGH WILL BE SETTING UP. SO WHILE
CHANCES OF ADDITIONAL SHOWERS FRIDAY-FRIDAY NIGHT ARE NOT THAT
HIGH...WE COULD STILL HAVE SCATTERED SHOWERS POPPING UP WITH WEAK
SHORTWAVES EMBEDDED IN THE LARGER DEVELOPING TROUGH...COMBINED
WITH DIURNAL HEATING.
TEMPERATURES THROUGH THE PERIOD WILL GENERALLY BE A FEW TO SEVERAL
DEGREES BELOW NORMAL VALUES.
&&
.LONG TERM /SATURDAY THROUGH TUESDAY/...
115 PM EDT UPDATE...
CLOSELY FOLLOWED WPC GUIDANCE.
A VERY ACTIVE PATTERN CONTINUES AND WILL REMAIN IN PLACE THRU THE
END OF THE FORECAST PERIOD. THIS PATTERN CONSISTS OF TROUGHING OVER
THE EAST AND RIDGING OVER THE WEST. KEPT A CHANCE FOR PRECIP OVER
THE CWA THRU THE WHOLE PERIOD. MULT WAVES WILL RIDE AROUND THE
TROUGH AND CREATE ENOUGH UPPR LVL SUPPORT FOR SHOWERS. THIS PATTERN
WILL ALSO CREATE CLOUDY SKIES ALONG WITH BELOW NORMAL TEMPS FOR THIS
TIME OF YR.
&&
.AVIATION /18Z WEDNESDAY THROUGH MONDAY/...
SCT-BKN CUMULUS HAS EVOLVED FROM AN MVFR STRATOCUMULUS DECK OF
THIS MORNING WITH THE STRONG LATE SUMMER SUN. CLOUD BASES WERE UP
TO 5 KFT AND MAY EVEN REACH 6 KFT. HAVE TAFS ALL VFR SCT CUMULUS
FOR THE AFTERNOON. SKIES WILL CLEAR OUT QUICKLY BY SUNSET. THEN WE
WILL SEE HIGH CLOUDS STREAM IN ACRS OUR NRN TAF SITES BTWN 5-6Z
AND THESE CLOUDS WILL SPREAD SOUTHWARD BY 12Z-13Z ACRS REST OF TAF
SITES. AN ALTOCUMULUS DECK ARND 10 TO 12 KFT WILL REACH KRME AND
KSYR BY 12-13Z. THE REST OF THE NY TAFS CUD SEE SOME PATCHY MID
CLDS UNDER BKN-OVC CIRRUS.
WITH MAINLY CLEAR SKIES MOST OF THE NGT...WE EXPECT IFR FG TO
DEVELOP AT LEAST FOR A FEW HOURS AT KELM. CROSS-OVER TEMPS WILL
FALL TO ABT 52-53F THIS PM WITH MINS EXPECTED TO BE CLOSE TO 50F
AT KELM. OUR LOCAL ELM FOG CHECKLIST RETURNS IFR FOG AT LEAST A
FEW HOURS OR SO BETWEEN 9 AND 13Z AND THUS HAVE PATCHY IFR FG AT
KELM. REST OF TAFS VFR THRU 18Z THU.
WINDS WILL BE NW ARND 10 KNOTS THIS AFTERNOON AND LIGHT WESTERLY
AFTER SUNSET AND W-SW 5-10 KNOTS THU AM.
.OUTLOOK...
THURS NGT/FRI/SAT/SUN/MON...CHANCE OF SHRA AND ASSOCIATED
RESTRICTIONS.
&&
.BGM WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NY...NONE.
&&
$$
SYNOPSIS...PCF
NEAR TERM...DJN/MDP
SHORT TERM...MDP
LONG TERM...MDP
AVIATION...DJN
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
347 PM EDT WED JUN 24 2015
.SYNOPSIS...
HOT AND HUMID CONDITIONS WILL PERSIST THROUGH THE END OF THE WEEK
WITH ISOLATED SHOWERS AND THUNDERSTORMS PRIMARILY DURING THE
AFTERNOONS AND EVENINGS. MUCH COOLER TEMPERATURES ALONG WITH A
BETTER CHANCE OF SHOWERS AND THUNDERSTORMS WILL DEVELOP THIS
WEEKEND. A DRYING TREND WILL BEGIN NEXT WEEK AS FRONT STALLED IN
THE AREA DISSIPATES AND HIGH PRESSURE RETURNS.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 200 PM WEDNESDAY...A HEAT ADVISORY REMAINS IN EFFECT
THROUGH EARLY THIS EVENING AS TEMPS SOAR INTO AND THROUGH THE 90S
ONCE AGAIN AND COMBINE WITH A VERY HUMID AIR MASS TO CREATE
DANGEROUS HEAT. VISIBLE IMAGERY KEEPING MOSTLY SUNNY SKIES OVER
MUCH OF THE AREA VERY EARLY THIS AFTERNOON BUT CU WAS DEVELOPING
AND CLUSTERING MAINLY OVER NORTHERN TIER COUNTIES WITH SOME ALSO
EVIDENT ALONG SEA BREEZE BOUNDARY.
NORTHERLY WINDS REACHING DOWN TO NORTH/SC BORDER EARLY THIS AFTN
AS WEAKENING COLD FRONT DROPS SLOWLY SOUTH. THIS WILL HELP TO
ADVECT SLIGHTLY DRIER AIR IN FROM THE N-NW AND WILL CREATE A
TIGHTER GRADIENT FLOW AND ENHANCED LOW LEVEL CONVERGENCE. OVERALL
IT WILL JUST PRODUCE A WIND SHIFT TO A MORE N-NE DIRECTION BEHIND
IT AS IT REACHES DOWN ALONG THE NC/SC BORDER CUTTING ACROSS OUR
LOCAL FORECAST AREA THIS AFTERNOON. THE MUCH DRIER AIR WILL
REMAIN WELL TO THE NORTHWEST AS SW FLOW AT THE SURFACE CONTINUES
TO KEEP A MOISTURE RICH AIR MASS OVER MUCH OF LOCAL FORECAST
AREA....WITH DEWPOINT TEMPS INTO THE 70S AND PCP WATER VALUES
NEAR 2 INCHES. ML CAPE VALUES WERE REACHING CLOSE TO 4000 J/KG
WITH LI VALUES TO -11. THIS UNSTABLE ENVIRONMENT WILL INCREASE THE
POTENTIAL FOR CONVECTIVE DEVELOPMENT THIS AFTERNOON. OVERALL THE
FORCING WILL BE SHALLOW WITH STEEP LOW LEVEL LAPSE RATES TO
INITIATE STORM DEVELOPMENT THIS AFTERNOON.
THE FOCUS OF CONVECTION WILL BE ALONG THIS SFC BOUNDARY AS IT
SHIFTS SLIGHTLY SOUTH THROUGH THIS AFTERNOON AND COMBINES WITH
ENHANCED CONVERGENCE ALONG SEA BREEZE BOUNDARY AS IT ADVANCES
INLAND ALONG WITH OTHER LOCALIZED BOUNDARIES. WITH ALL THIS BEING
SAID...THERE IS NOT MUCH IN THE WAY OF UPPER LEVEL SUPPORT AS WE
REMAIN ON THE TOP OF RIDGE ALOFT. THE SW FLOW FROM THE SFC THROUGH
THE LOW LEVEL FLOW WILL VEER TO BECOME MORE WESTERLY WHICH WILL
AID IN DOWNSLOPE FLOW AND HEATING...SOME DRYING AND WILL ALSO HELP
TO KEEP SEA BREEZE PINNED CLOSER TO THE COAST INITIALLY. AS
HEATING INCREASES EXPECT CU AND SHWRS/TSTMS TO FORM ALONG
CONVERGENT BOUNDARIES. SPC HAS KEPT OUR AREA IN A MARGINAL RISK
FOR SVR STORMS AS A MODERATELY UNSTABLE AIR MASS YIELDS STRONG
UPDRAFT/DOWNDRAFT GROWTH WITH POTENTIAL FOR ISOLATED DAMAGING
WINDS. THE HRRR SHOWS MAIN FOCUS ALONG WEAKENING FRONT FROM
MARLBORO TO PENDER COUNTIES BY 18Z AND OTHER MORE ISOLATED
CONVECTIVE DEVELOPMENT ALONG SEA BREEZE FROM GEORGETOWN COUNTY UP
THROUGH THE GRAND STRAND INTO THE CAPE FEAR AREA. THE STEERING
FLOW WILL BE OUT OF THE NW WHICH WILL PUSH ALL STORMS SOUTHEAST
AND TOWARD THE COAST WITH OTHER STORMS DEVELOPING ALONG COLLIDING
BOUNDARIES.
MOST OF THIS ACTIVITY WILL END THIS EVENING AS CONVECTION WILL BE
ALMOST EXCLUSIVELY DIURNALLY FORCED. KEPT SOME LINGERING POPS INTO
LATE THIS EVENING BUT NOT TOO CONFIDENT AS TO HOW MUCH WILL LINGER
AFTER DARK. MIN TEMPS TONIGHT WILL AGAIN BE QUITE WARM...DROPPING
ONLY TO AROUND 80 AT THE BEACHES...75 WELL INLAND.
&&
.SHORT TERM /THURSDAY THROUGH FRIDAY NIGHT/...
AS OF 3 AM WEDNESDAY...LONG LIVED MID LEVEL RIDGE WILL START SHOWING
SIGNS OF WEAKENING DURING THE PERIOD ALTHOUGH THE HEAT AND HUMIDITY
WILL CONTINUE. RIDGE HOLDS ON THU BUT STARTS TO BREAK DOWN LATER FRI
AS 5H TROUGH APPROACHES FROM THE NORTHWEST. AT THE SURFACE THE
BERMUDA HIGH AND PIEDMONT TROUGH REMAIN IN PLACE ALONG WITH DAILY
DEVELOPMENT OF THE AFTERNOON SEA BREEZE. DEEP MOISTURE REMAINS IN
PLACE WITH PRECIPITABLE WATER VALUES RUNNING BETWEEN 1.75 AND 2
INCHES. MID LEVEL LAPSE RATES ARE STEEP ENOUGH FOR DEVELOPMENT OF
MODERATE TO STRONG UPDRAFTS WITH ONLY A SHALLOW LAYER OF LESS
FAVORABLE LAPSE RATES TO OVERCOME. THE PROBLEM IS THE HEIGHT OF THIS
SHALLOW STABLE LAYER WHICH IS BASED BETWEEN 7K AND 8K FT. THIS MAY
BE TOO HIGH FOR THE SEA BREEZE AND PIEDMONT TROUGH TO OVERCOME ON
THEIR OWN. ATMOSPHERE MAY REQUIRE SOME BOUNDARY INTERACTION...WITH
LEFT OVER CONVECTIVE BOUNDARIES...AND HEATING BEFORE DEEPER
CONVECTION IS ABLE TO DEVELOP. WILL CARRY CHC POP EACH AFTERNOON BUT
FAVOR A LATER TIMING GIVEN THE AFOREMENTIONED LIMITATIONS.
TEMPERATURES WILL CONTINUE TO RUN WELL ABOVE CLIMO WITH HIGHS IN THE
MID 90S AND LOWS IN THE MID TO UPPER 70S.
&&
.LONG TERM /SATURDAY THROUGH TUESDAY/...
AS OF 3 AM WEDNESDAY...MID LEVEL TROUGH AND STALLED SURFACE BOUNDARY
WILL RESULT IN UNSETTLED WEATHER FOR MUCH OF THE PERIOD. LARGE 5H
TROUGH SETS UP OVER THE EASTERN CONUS BUT THE TROUGHS AXIS WILL
REMAIN WEST OF THE AREA THROUGH TUE. COMBINATION OF DIURNAL
HEATING...DEEP AND MOIST SOUTHWEST FLOW...AND AN OCCASIONAL
SHORTWAVE ROTATING AROUND THE BASE OF THE TROUGH WILL LEAD TO AN
INCREASE IN SHOWER AND THUNDERSTORM ACTIVITY ACROSS THE AREA. BEST
CHANCES WILL BE SAT INTO SUN AS THE TROUGH ARRIVES AND PUSHES A COLD
FRONT INTO THE AREA. DEEP MOISTURE PRESENT AHEAD OF THE TROUGH ALONG
WITH SHORTWAVE ENERGY WARRANTS AT LEAST HIGH CHC TO LIKELY POP SAT.
MOISTURE LINGERS THROUGH THE FIRST HALF OF SUN BUT LOW LEVEL
INSTABILITY DECREASES. WILL HOLD ONTO PRECIP CHANCES SUN AND SUN
NIGHT BUT TREND POP DOWNWARD...ESPECIALLY SUN NIGHT.
MID LEVEL DRY AIR WORKS IN FOR LATE SUN THROUGH TUE AS A LOBE OF THE
5H TROUGH EJECTS NORTHEAST...WITH WEAK SUBSIDENCE OVER THE
SOUTHEAST. LONGWAVE TROUGH AXIS REMAINS WEST OF THE AREA AND THE
DISSIPATING FRONT WILL REMAIN STALLED OVER OR JUST EAST OF THE AREA.
THE LACK OF MID LEVEL MOISTURE WILL HINDER DEEPER CONVECTION BUT
STILL EXPECT AT LEAST SOME DEVELOPMENT. PLAN TO MAINTAIN INHERITED
SILENT POP MON AND TUE GIVEN AN UNFAVORABLE ENVIRONMENT AND A FAIR
AMOUNT OF UNCERTAINTY.
HIGH TEMPERATURES WILL BE NEAR TO SLIGHTLY BELOW CLIMO DUE TO THE
INCREASED MOISTURE/CLOUD COVER ALONG WITH THE POTENTIAL FOR MORE
CONVECTION. LOWS WILL CONTINUE TO RUN ABOVE CLIMO.
&&
.AVIATION /17Z WEDNESDAY THROUGH SUNDAY/...
AS OF 12Z...TERMINALS ARE VFR THIS MORNING AND VFR WILL LIKELY
CONTINUE THROUGH 18Z. WINDS WILL BE SW-W 5-10 KTS EXCEPT BECOMING
SSW AT THE COASTAL TERMINALS MID MORNING ON.
THUNDERSTORMS RESULTING IN TEMPO REDUCED FLIGHT CONDITIONS AND GUSTY
WINDS WILL BE THE BIGGEST THREATS TO AVIATION MAINLY THIS AFTERNOON
AND EVENING. THUNDERSTORMS SHOULD DEVELOP AFTER 17Z INITIALLY ALONG
A WEAK FRONT NEAR KLBT TO N OF KILM. DRY AIR IN THE MID LEVELS
SHOULD ALLOW FOR LESS ACTIVITY TO DEVELOP ELSEWHERE. SOME BOUNDARIES
COULD THROWN OFF TO THE SOUTH ALLOWING THUNDERSTORMS TO DEVELOP
FURTHER S IN THE AFTERNOON AND EVENING. CONFIDENCE OF THUNDERSTORM
OCCURRENCE IS HIGHEST N.
ACTIVITY DISSIPATES DURING THE EVENING. WINDS MAY BE VARIABLE IN THE
EVENING/EARLY MORNING WHERE STORMS HAVE OCCURRED...BUT GENERALLY
LIGHT SW WINDS CAN BE EXPECTED OVERNIGHT WITH VFR CONDITIONS.
EXTENDED OUTLOOK...ISOLATED SHOWERS AND STORMS THURSDAY. MODERATE
CONFIDENCE FOR SCATTERED TO NUMEROUS SHOWERS AND STORMS FRIDAY
AFTERNOON THROUGH SUNDAY WITH MVFR/IFR CONDITIONS AND POSSIBLE HEAVY
RAIN.
&&
.MARINE...
NEAR TERM /THROUGH TONIGHT/...
AS OF 200 PM WEDNESDAY...WINDS WILL REMAIN OUT OF THE SW BETWEEN
ATLANTIC HIGH PRESSURE AND TROUGH INLAND. SHOULD REMAIN BETWEEN 10
AND 15 KTS OVER MOST OF THE WATERS...BUT WILL SEE SOME HIGHER
GUSTS OVER 20 KTS. SEAS WILL BE 2 TO 4 FT WITH THE SW WIND CHOP
DOMINATING. WINDS WILL SPIKE UP AND REMAIN GUSTIER THROUGH EARLY THIS
EVENING AS SEA BREEZE ENHANCES THE FLOW.
SHORT TERM /THURSDAY THROUGH FRIDAY NIGHT/...
AS OF 3 AM WEDNESDAY...BERMUDA HIGH AND PIEDMONT TROUGH COMBO
WILL MAINTAIN SOUTHWEST FLOW ACROSS THE WATERS THROUGH THE PERIOD.
GRADIENT WILL INCREASE THU INTO FRI WITH SOLID 20 KT DEVELOPING
THU NIGHT AND CONTINUING THROUGH THE END OF THE PERIOD. SEAS 3 TO
4 FT AT THE START OF THE PERIOD WILL BUILD TO 3 TO 5 FT AND
POSSIBLY 4 TO 6 FT FRI AND FRI NIGHT. HEADLINES MAY BE REQUIRED
FOR THE SECOND HALF OF THE PERIOD.
LONG TERM /SATURDAY THROUGH SUNDAY/...
AS OF 3 AM WEDNESDAY...BERMUDA HIGH COMBINED WITH LOW PRESSURE
ROTATING THROUGH THE MID ATLANTIC AND THE APPROACH OF THE
ASSOCIATED COLD FRONT WILL PINCH THE SURFACE GRADIENT SAT INTO
SUN. SOUTHWEST FLOW WILL REMAIN 15 TO 20 KT THOUGH THE PERIOD.
FRONT IS NOT EXPECTED TO MOVE OVER THE WATERS BUT INSTEAD REMAIN
STALLED INLAND. THIS WILL KEEP WINDS OUT OF THE SOUTHWEST THROUGH
SUN. SEAS WILL RUN 3 TO 5 FT BUT GIVEN THE EXTENDED PERIOD OF
WINDS AROUND 20 KT CANNOT RULE OUT SOME 6 FT SEAS...ESPECIALLY
WATERS NEAR 20 NM OPEN TO SOUTHWEST FETCH AND HEADLINES COULD BE
REQUIRED FOR AT LEAST A PORTION OF THE PERIOD.
&&
.ILM WATCHES/WARNINGS/ADVISORIES...
SC...HEAT ADVISORY UNTIL 8 PM EDT THIS EVENING FOR SCZ017-023-024-
032-033-039-053>056.
HEAT ADVISORY FROM 10 AM TO 8 PM EDT THURSDAY FOR SCZ017-023-
024-032-033-039-053>056.
NC...HEAT ADVISORY UNTIL 8 PM EDT THIS EVENING FOR NCZ087-096-099-
105>110.
HEAT ADVISORY FROM 10 AM TO 8 PM EDT THURSDAY FOR NCZ087-096-
099-105>110.
MARINE...NONE.
&&
$$
NEAR TERM...RGZ
SHORT TERM...III
LONG TERM...III
AVIATION...RGZ/MRR
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
130 PM EDT WED JUN 24 2015
.SYNOPSIS...
HOT AND HUMID CONDITIONS WILL PERSIST THROUGH THE END OF THE WEEK
WITH ISOLATED SHOWERS AND THUNDERSTORMS PRIMARILY EACH AFTERNOON AND
EVENING. COOLER TEMPERATURES ALONG WITH A BETTER CHANCE OF SHOWERS
AND THUNDERSTORMS WILL DEVELOP THIS WEEKEND. A DRYING TREND WILL
BEGIN NEXT WEEK AS FRONT STALLED IN THE AREA DISSIPATES AND HIGH
PRESSURE RETURNS.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 10 AM WEDNESDAY...A HEAT ADVISORY REMAINS IN EFFECT THROUGH
EARLY THIS EVENING AS TEMPS SOAR INTO AND THROUGH THE 90S ONCE AGAIN
AND COMBINE WITH A VERY HUMID AIR MASS TO CREATE DANGEROUS HEAT.
A COLD FRONT EXTENDING FROM THE MOUNTAINS OF WESTERN NC E-NE TOWARD
NC/VA COAST THIS MORNING WILL PUSH ONLY SLOWLY SOUTH AS IT WASHES
OUT. THIS WILL HELP TO ADVECT SLIGHTLY DRIER AIR IN FROM THE N-NW
AND WILL CREATE A TIGHTER GRADIENT FLOW PRODUCING ENHANCED LOW LEVEL
CONVERGENCE ALONG TROUGH AHEAD OF IT. OVERALL IT WILL JUST PRODUCE A
WIND SHIFT TO A MORE N-NE DIRECTION BEHIND IT AS IT REACHES DOWN
ALONG THE NC/SC BORDER CUTTING ACROSS OUR LOCAL FORECAST AREA THIS
AFTERNOON. THE MUCH LOWER DEWPOINT AIR WILL REMAIN WELL TO THE NORTH
AS SW FLOW AT THE SURFACE CONTINUES TO KEEP A MOISTURE RICH AIR MASS
OVER MUCH OF LOCAL FORECAST AREA....WITH DEWPOINT TEMPS INTO THE 70S
THIS MORNING AND PCP WATER VALUES NEAR 2 INCHES. ML CAPE VALUES WERE
REACHING CLOSE TO 4000 J/KG WITH LI VALUES TO -11. THIS UNSTABLE
ENVIRONMENT WILL INCREASE THE POTENTIAL FOR CONVECTIVE DEVELOPMENT
THIS AFTERNOON. OVERALL THE FORCING WILL BE SHALLOW WITH STEEP LOW
LEVEL LAPSE RATES TO INITIATE STORM DEVELOPMENT THIS AFTERNOON.
THE FOCUS OF CONVECTION WILL BE ALONG THIS SFC BOUNDARY AS IT SHIFTS
SLIGHTLY SOUTH THROUGH THIS AFTERNOON AND COMBINES WITH ENHANCED
CONVERGENCE ALONG SEA BREEZE BOUNDARY AS IT ADVANCES INLAND AND
OTHER LOCALIZED BOUNDARIES. WITH ALL THIS BEING SAID...THERE IS NOT
MUCH IN THE WAY OF UPPER LEVEL SUPPORT AS WE REMAIN ON THE TOP OF
RIDGE ALOFT. THE SW FLOW FROM THE SFC THROUGH THE LOW LEVEL FLOW
WILL VEER TO BECOME MORE WESTERLY WHICH WILL AID IN DOWNSLOPE FLOW
AND HEATING...SOME DRYING AND WILL ALSO HELP TO KEEP SEA BREEZE
PINNED CLOSER TO THE COAST INITIALLY. AS HEATING INCREASES EXPECT CU
AND SHWRS/TSTMS TO FORM ALONG CONVERGENT BOUNDARIES. SPC HAS KEPT
OUR AREA IN A MARGINAL RISK FOR SVR STORMS AS A MODERATELY UNSTABLE
AIR MASS YIELDS STRONG UPDRAFT/DOWNDRAFT GROWTH WITH POTENTIAL FOR
ISOLATED DAMAGING WINDS. THE HRRR SHOWS MAIN FOCUS ALONG WEAKENING
FRONT FROM MARLBORO TO PENDER COUNTIES BY 18Z AND OTHER MORE
ISOLATED CONVECTIVE DEVELOPMENT ALONG SEA BREEZE FROM GEORGETOWN
COUNTY UP THROUGH THE GRAND STRAND INTO THE CAPE FEAR AREA. THE
STEERING FLOW WILL BE OUT OF THE NW WHICH WILL PUSH ALL STORMS
SOUTHEAST AND TOWARD THE COAST WITH OTHER STORMS DEVELOPING ALONG
COLLIDING BOUNDARIES.
MOST OF THIS ACTIVITY WILL END THIS EVENING AS CONVECTION WILL BE
ALMOST EXCLUSIVELY DIURNALLY FORCED. MIN TEMPS TONIGHT WILL AGAIN BE
QUITE WARM...DROPPING ONLY TO AROUND 80 AT THE BEACHES...75 WELL
INLAND.
&&
.SHORT TERM /THURSDAY THROUGH FRIDAY NIGHT/...
AS OF 130 PM WEDNESDAY...HOT/HUMID SOUTHWESTERLY FLOW WILL CONTINUE
THURSDAY AND FRIDAY NIGHT WHILE MID/UPPER RIDGE MAINTAINS ITS
PRESENCE FOR A COUPLE MORE DAYS. THE HEAT INDEX IS PROJECTED TO
SURPASS HEAT ADVISORY CRITERIA THURSDAY AND WILL LIKELY DO SO AGAIN
ON FRIDAY. THE SOUTHWESTERLY FLOW WILL ALSO SUPPORT ABOVE NORMAL MIN
TEMPERATURES EACH NIGHT WITH LOWS IN THE MID TO UPPER 70S. HIGHS
EACH DAY ARE EXPECTED TO RANGE FROM THE LOWER 90S AT THE COAST TO
THE UPPER 90S TO AROUND 100. ALTHOUGH THE BETTER CHANCES FOR
SHOWERS/TSTMS EXISTS IN THE EXTENDED A CHANCE EXISTS PRIMARILY FOR
EACH AFTERNOON AND EVENING WITH THE SEA BREEZE AS A TRIGGER. PLENTY
OF INSTABILITY EXISTS SO ANY STORM THAT DOES FIRE COULD BE STRONG.
&&
.LONG TERM /SATURDAY THROUGH WEDNESDAY/...
AS OF 130 PM WEDNESDAY...A LONG WAVE TROUGH WILL DEVELOP OVER THE
GREAT LAKES BY SATURDAY AND BRING SOME RELIEF FROM THE EXTENDED HEAT
WAVE OF THE LAST COUPLE OF WEEKS. SOUTHWEST FLOW EAST OF THE TROUGH
AXIS WILL RESULT IN A SURGE OF GULF MOISTURE AND UNSETTLED WEATHER
SATURDAY INTO EARLY SUNDAY. CONVECTION WILL COME TO AN END AS A COLD
FRONT MOVES OFF THE COAST BY SUNDAY MORNING...AND SURFACE HIGH
PRESSURE SHOULD BRING TEMPERATURES DOWN TO AROUND CLIMO FOR MONDAY.
RETURN FLOW WILL SET UP TUESDAY AND CONTINUE WEDNESDAY BUT THE LACK
OF DEEP MOISTURE WILL KEEP CONVECTION SCATTERED AT BEST.
&&
.AVIATION /18Z WEDNESDAY THROUGH MONDAY/...
AS OF 1730Z...TERMINALS ARE VFR THIS AFTERNOON. WINDS ARE LIGHT AND
VARIABLE AT KFLO/KLBT SSW-W AT THE COASTAL TERMINALS.
THUNDERSTORMS RESULTING IN TEMPO REDUCED FLIGHT CONDITIONS AND GUSTY
WINDS WILL BE THE BIGGEST THREATS TO AVIATION MAINLY THIS AFTERNOON
AND EVENING. MOSTLY ISOLATED THUNDERSTORMS WILL DEVELOP ALONG A WEAK
TROUGH AHEAD OF A WEAK COLD FRONT FROM KLBT TO N OF KILM. BEST
CONFIDENCE OF OCCURRENCE WILL BE AT KILM WITH TROUGH/SEA BREEZE
BOUNDARY INTERACTIONS. SOME OUTFLOW BOUNDARIES COULD BE THROWN OFF
TO THE SOUTH ALLOWING THUNDERSTORMS TO RE-DEVELOP FURTHER S TOWARDS
THE SOUTHERN TERMINALS LATER THIS AFTERNOON AND EVENING...BUT
ACTIVITY SHOULD BE WEAKER AND EVEN ISOLATED.
ACTIVITY DISSIPATES DURING THE EVENING WITH LOSS OF HEATING. WINDS
MAY BE VARIABLE IN THE EVENING/EARLY MORNING WHERE STORMS HAVE
OCCURRED...BUT GENERALLY WILL RECOVER TO LIGHT SW FOR THE OVERNIGHT
WITH VFR CONDITIONS. VFR CONTINUES AFTER SUNRISE WITH LIGHT SW WINDS
CONTINUING.
EXTENDED OUTLOOK...ISOLATED SHOWERS AND STORMS THURSDAY. MODERATE
CONFIDENCE FOR SCATTERED TO NUMEROUS SHOWERS AND STORMS FRIDAY
AFTERNOON THROUGH SUNDAY WITH MVFR/IFR CONDITIONS AND POSSIBLE HEAVY
RAIN.
&&
.MARINE... NEAR TERM /THROUGH TONIGHT/...
AS OF 12 PM WEDNESDAY...WINDS WILL REMAIN OUT OF THE SW 10 TO 15 KTS
BETWEEN ATLANTIC HIGH PRESSURE AND TROUGH INLAND. SEAS WILL BE 2 TO
4 FT WITH THE SW WIND CHOP DOMINATING. WINDS WILL SPIKE UP AND BE
GUSTY THROUGH THIS AFTERNOON AS SEA BREEZE ENHANCES THE FLOW.
SHORT TERM /THURSDAY THROUGH FRIDAY NIGHT/...
AS OF 130 PM WEDNESDAY...THE SOUTHWEST PRESSURE GRADIENT WILL
PERSIST BETWEEN INLAND TROUGH OF LOW PRESSURE AND HIGH PRESSURE OFF
THE SOUTHEAST UNITED STATES COAST EACH DAY. THE GRADIENT WILL
TIGHTEN BY THURSDAY AFTERNOON AND BREEZY SOUTHWEST FLOW WILL CARRY
INTO FRIDAY. WAVE GUIDANCE INDICATES THAT A 1-2 FT SOUTHEAST SWELL
WILL REMAIN MASKED BY THE MORE DOMINANT LOWER PERIOD WAVES AS A
RESULT OF THE SOUTHWESTERLY FETCH. THUS NOT THE BEST OF BOATING FOR
THE COASTAL WATERS WITH SOME STEEP CONDITIONS POSSIBLE.
LONG TERM /SATURDAY THROUGH MONDAY/...
AS OF 130 PM WEDNESDAY...SOUTHWEST FLOW WILL INCREASE SATURDAY WITH
A TIGHTENING GRADIENT AHEAD OF A COLD FRONT. SMALL CRAFT ADVISORY
CONDITIONS ARE POSSIBLE SATURDAY INTO EARLY SUNDAY AS WINDS SPEEDS
ARE EXPECTED TO REACH 20-25 KTS. THE GRADIENT WILL RELAX WITH THE
APPROACH FROM THE WEST OF THE SURFACE TROUGH AND ASSOCIATED COLD
FRONT. SCATTERED TO NUMEROUS SHOWERS AND TSTMS AHEAD OF THE FRONT
WILL DIMINISH ON SUNDAY...AND WINDS ARE EXPECTED TO SHIFT TO THE
NORTHEAST SUNDAY NIGHT AS HIGH PRESSURE BUILDS OVER THE WATERS.
&&
.ILM WATCHES/WARNINGS/ADVISORIES...
SC...HEAT ADVISORY UNTIL 8 PM EDT THIS EVENING FOR SCZ017-023-024-
032-033-039-053>056.
HEAT ADVISORY FROM 10 AM TO 8 PM EDT THURSDAY FOR SCZ017-023-
024-032-033-039-053>056.
NC...HEAT ADVISORY UNTIL 8 PM EDT THIS EVENING FOR NCZ087-096-099-
105>110.
HEAT ADVISORY FROM 10 AM TO 8 PM EDT THURSDAY FOR NCZ087-096-
099-105>110.
MARINE...NONE.
&&
$$
NEAR TERM...RGZ
SHORT TERM...SRP
LONG TERM...CRM
AVIATION...MRR/RGZ
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
1212 PM EDT WED JUN 24 2015
.SYNOPSIS...
HOT AND HUMID CONDITIONS WILL PERSIST THROUGH THE END OF THE WEEK
WITH ISOLATED SHOWERS AND THUNDERSTORMS PRIMARILY DURING THE
AFTERNOONS AND EVENINGS. MUCH COOLER TEMPERATURES ALONG WITH A
BETTER CHANCE OF SHOWERS AND THUNDERSTORMS WILL DEVELOP THIS
WEEKEND. A DRYING TREND WILL BEGIN NEXT WEEK AS FRONT STALLED IN
THE AREA DISSIPATES AND HIGH PRESSURE RETURNS.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 1000 AM WEDNESDAY...A HEAT ADVISORY REMAINS IN EFFECT
THROUGH EARLY THIS EVENING AS TEMPS SOAR INTO AND THROUGH THE 90S
ONCE AGAIN AND COMBINE WITH A VERY HUMID AIR MASS TO CREATE
DANGEROUS HEAT.
A COLD FRONT EXTENDING FROM THE MOUNTAINS OF WESTERN NC E-NE
TOWARD NC/VA COAST THIS MORNING WILL PUSH ONLY SLOWLY SOUTH AS IT
WASHES OUT. THIS WILL HELP TO ADVECT SLIGHTLY DRIER AIR IN FROM
THE N-NW AND WILL CREATE A TIGHTER GRADIENT FLOW PRODUCING
ENHANCED LOW LEVEL CONVERGENCE ALONG TROUGH AHEAD OF IT. OVERALL
IT WILL JUST PRODUCE A WIND SHIFT TO A MORE N-NE DIRECTION BEHIND
IT AS IT REACHES DOWN ALONG THE NC/SC BORDER CUTTING ACROSS OUR
LOCAL FORECAST AREA THIS AFTERNOON. THE MUCH LOWER DEWPOINT AIR
WILL REMAIN WELL TO THE NORTH AS SW FLOW AT THE SURFACE CONTINUES
TO KEEP A MOISTURE RICH AIR MASS OVER MUCH OF LOCAL FORECAST
AREA....WITH DEWPOINT TEMPS INTO THE 70S THIS MORNING AND PCP
WATER VALUES NEAR 2 INCHES. ML CAPE VALUES WERE REACHING CLOSE TO
4000 J/KG WITH LI VALUES TO -11. THIS UNSTABLE ENVIRONMENT WILL
INCREASE THE POTENTIAL FOR CONVECTIVE DEVELOPMENT THIS AFTERNOON.
OVERALL THE FORCING WILL BE SHALLOW WITH STEEP LOW LEVEL LAPSE
RATES TO INITIATE STORM DEVELOPMENT THIS AFTERNOON.
THE FOCUS OF CONVECTION WILL BE ALONG THIS SFC BOUNDARY AS IT
SHIFTS SLIGHTLY SOUTH THROUGH THIS AFTERNOON AND COMBINES WITH
ENHANCED CONVERGENCE ALONG SEA BREEZE BOUNDARY AS IT ADVANCES
INLAND AND OTHER LOCALIZED BOUNDARIES. WITH ALL THIS BEING
SAID...THERE IS NOT MUCH IN THE WAY OF UPPER LEVEL SUPPORT AS WE
REMAIN ON THE TOP OF RIDGE ALOFT. THE SW FLOW FROM THE SFC THROUGH
THE LOW LEVEL FLOW WILL VEER TO BECOME MORE WESTERLY WHICH WILL
AID IN DOWNSLOPE FLOW AND HEATING...SOME DRYING AND WILL ALSO HELP
TO KEEP SEA BREEZE PINNED CLOSER TO THE COAST INITIALLY. AS
HEATING INCREASES EXPECT CU AND SHWRS/TSTMS TO FORM ALONG
CONVERGENT BOUNDARIES. SPC HAS KEPT OUR AREA IN A MARGINAL RISK
FOR SVR STORMS AS A MODERATELY UNSTABLE AIR MASS YIELDS STRONG
UPDRAFT/DOWNDRAFT GROWTH WITH POTENTIAL FOR ISOLATED DAMAGING
WINDS. THE HRRR SHOWS MAIN FOCUS ALONG WEAKENING FRONT FROM
MARLBORO TO PENDER COUNTIES BY 18Z AND OTHER MORE ISOLATED
CONVECTIVE DEVELOPMENT ALONG SEA BREEZE FROM GEORGETOWN COUNTY UP
THROUGH THE GRAND STRAND INTO THE CAPE FEAR AREA. THE STEERING
FLOW WILL BE OUT OF THE NW WHICH WILL PUSH ALL STORMS SOUTHEAST
AND TOWARD THE COAST WITH OTHER STORMS DEVELOPING ALONG COLLIDING
BOUNDARIES.
MOST OF THIS ACTIVITY WILL END THIS EVENING AS CONVECTION WILL BE
ALMOST EXCLUSIVELY DIURNALLY FORCED. MIN TEMPS TONIGHT WILL AGAIN
BE QUITE WARM...DROPPING ONLY TO AROUND 80 AT THE BEACHES...75
WELL INLAND.
&&
.SHORT TERM /THURSDAY THROUGH FRIDAY NIGHT/...
AS OF 3 AM WEDNESDAY...LONG LIVED MID LEVEL RIDGE WILL START SHOWING
SIGNS OF WEAKENING DURING THE PERIOD ALTHOUGH THE HEAT AND HUMIDITY
WILL CONTINUE. RIDGE HOLDS ON THU BUT STARTS TO BREAK DOWN LATER FRI
AS 5H TROUGH APPROACHES FROM THE NORTHWEST. AT THE SURFACE THE
BERMUDA HIGH AND PIEDMONT TROUGH REMAIN IN PLACE ALONG WITH DAILY
DEVELOPMENT OF THE AFTERNOON SEA BREEZE. DEEP MOISTURE REMAINS IN
PLACE WITH PRECIPITABLE WATER VALUES RUNNING BETWEEN 1.75 AND 2
INCHES. MID LEVEL LAPSE RATES ARE STEEP ENOUGH FOR DEVELOPMENT OF
MODERATE TO STRONG UPDRAFTS WITH ONLY A SHALLOW LAYER OF LESS
FAVORABLE LAPSE RATES TO OVERCOME. THE PROBLEM IS THE HEIGHT OF THIS
SHALLOW STABLE LAYER WHICH IS BASED BETWEEN 7K AND 8K FT. THIS MAY
BE TOO HIGH FOR THE SEA BREEZE AND PIEDMONT TROUGH TO OVERCOME ON
THEIR OWN. ATMOSPHERE MAY REQUIRE SOME BOUNDARY INTERACTION...WITH
LEFT OVER CONVECTIVE BOUNDARIES...AND HEATING BEFORE DEEPER
CONVECTION IS ABLE TO DEVELOP. WILL CARRY CHC POP EACH AFTERNOON BUT
FAVOR A LATER TIMING GIVEN THE AFOREMENTIONED LIMITATIONS.
TEMPERATURES WILL CONTINUE TO RUN WELL ABOVE CLIMO WITH HIGHS IN THE
MID 90S AND LOWS IN THE MID TO UPPER 70S.
&&
.LONG TERM /SATURDAY THROUGH TUESDAY/...
AS OF 3 AM WEDNESDAY...MID LEVEL TROUGH AND STALLED SURFACE BOUNDARY
WILL RESULT IN UNSETTLED WEATHER FOR MUCH OF THE PERIOD. LARGE 5H
TROUGH SETS UP OVER THE EASTERN CONUS BUT THE TROUGHS AXIS WILL
REMAIN WEST OF THE AREA THROUGH TUE. COMBINATION OF DIURNAL
HEATING...DEEP AND MOIST SOUTHWEST FLOW...AND AN OCCASIONAL
SHORTWAVE ROTATING AROUND THE BASE OF THE TROUGH WILL LEAD TO AN
INCREASE IN SHOWER AND THUNDERSTORM ACTIVITY ACROSS THE AREA. BEST
CHANCES WILL BE SAT INTO SUN AS THE TROUGH ARRIVES AND PUSHES A COLD
FRONT INTO THE AREA. DEEP MOISTURE PRESENT AHEAD OF THE TROUGH ALONG
WITH SHORTWAVE ENERGY WARRANTS AT LEAST HIGH CHC TO LIKELY POP SAT.
MOISTURE LINGERS THROUGH THE FIRST HALF OF SUN BUT LOW LEVEL
INSTABILITY DECREASES. WILL HOLD ONTO PRECIP CHANCES SUN AND SUN
NIGHT BUT TREND POP DOWNWARD...ESPECIALLY SUN NIGHT.
MID LEVEL DRY AIR WORKS IN FOR LATE SUN THROUGH TUE AS A LOBE OF THE
5H TROUGH EJECTS NORTHEAST...WITH WEAK SUBSIDENCE OVER THE
SOUTHEAST. LONGWAVE TROUGH AXIS REMAINS WEST OF THE AREA AND THE
DISSIPATING FRONT WILL REMAIN STALLED OVER OR JUST EAST OF THE AREA.
THE LACK OF MID LEVEL MOISTURE WILL HINDER DEEPER CONVECTION BUT
STILL EXPECT AT LEAST SOME DEVELOPMENT. PLAN TO MAINTAIN INHERITED
SILENT POP MON AND TUE GIVEN AN UNFAVORABLE ENVIRONMENT AND A FAIR
AMOUNT OF UNCERTAINTY.
HIGH TEMPERATURES WILL BE NEAR TO SLIGHTLY BELOW CLIMO DUE TO THE
INCREASED MOISTURE/CLOUD COVER ALONG WITH THE POTENTIAL FOR MORE
CONVECTION. LOWS WILL CONTINUE TO RUN ABOVE CLIMO.
&&
.AVIATION /16Z WEDNESDAY THROUGH SUNDAY/...
AS OF 12Z...TERMINALS ARE VFR THIS MORNING AND VFR WILL LIKELY
CONTINUE THROUGH 18Z. WINDS WILL BE SW-W 5-10 KTS EXCEPT BECOMING
SSW AT THE COASTAL TERMINALS MID MORNING ON.
THUNDERSTORMS RESULTING IN TEMPO REDUCED FLIGHT CONDITIONS AND GUSTY
WINDS WILL BE THE BIGGEST THREATS TO AVIATION MAINLY THIS AFTERNOON
AND EVENING. THUNDERSTORMS SHOULD DEVELOP AFTER 17Z INITIALLY ALONG
A WEAK FRONT NEAR KLBT TO N OF KILM. DRY AIR IN THE MID LEVELS
SHOULD ALLOW FOR LESS ACTIVITY TO DEVELOP ELSEWHERE. SOME BOUNDARIES
COULD THROWN OFF TO THE SOUTH ALLOWING THUNDERSTORMS TO DEVELOP
FURTHER S IN THE AFTERNOON AND EVENING. CONFIDENCE OF THUNDERSTORM
OCCURRENCE IS HIGHEST N.
ACTIVITY DISSIPATES DURING THE EVENING. WINDS MAY BE VARIABLE IN THE
EVENING/EARLY MORNING WHERE STORMS HAVE OCCURRED...BUT GENERALLY
LIGHT SW WINDS CAN BE EXPECTED OVERNIGHT WITH VFR CONDITIONS.
EXTENDED OUTLOOK...ISOLATED SHOWERS AND STORMS THURSDAY. MODERATE
CONFIDENCE FOR SCATTERED TO NUMEROUS SHOWERS AND STORMS FRIDAY
AFTERNOON THROUGH SUNDAY WITH MVFR/IFR CONDITIONS AND POSSIBLE HEAVY
RAIN.
&&
.MARINE...
NEAR TERM /THROUGH TONIGHT/...
AS OF 1200 PM WEDNESDAY...WINDS WILL REMAIN OUT OF THE SW 10 TO 15
KTS BETWEEN ATLANTIC HIGH PRESSURE AND TROUGH INLAND. SEAS WILL BE
2 TO 4 FT WITH THE SW WIND CHOP DOMINATING. WINDS WILL SPIKE UP
AND BE GUSTY THROUGH THIS AFTERNOON AS SEA BREEZE ENHANCES THE
FLOW.
SHORT TERM /THURSDAY THROUGH FRIDAY NIGHT/...
AS OF 3 AM WEDNESDAY...BERMUDA HIGH AND PIEDMONT TROUGH COMBO
WILL MAINTAIN SOUTHWEST FLOW ACROSS THE WATERS THROUGH THE PERIOD.
GRADIENT WILL INCREASE THU INTO FRI WITH SOLID 20 KT DEVELOPING
THU NIGHT AND CONTINUING THROUGH THE END OF THE PERIOD. SEAS 3 TO
4 FT AT THE START OF THE PERIOD WILL BUILD TO 3 TO 5 FT AND
POSSIBLY 4 TO 6 FT FRI AND FRI NIGHT. HEADLINES MAY BE REQUIRED
FOR THE SECOND HALF OF THE PERIOD.
LONG TERM /SATURDAY THROUGH SUNDAY/...
AS OF 3 AM WEDNESDAY...BERMUDA HIGH COMBINED WITH LOW PRESSURE
ROTATING THROUGH THE MID ATLANTIC AND THE APPROACH OF THE
ASSOCIATED COLD FRONT WILL PINCH THE SURFACE GRADIENT SAT INTO
SUN. SOUTHWEST FLOW WILL REMAIN 15 TO 20 KT THOUGH THE PERIOD.
FRONT IS NOT EXPECTED TO MOVE OVER THE WATERS BUT INSTEAD REMAIN
STALLED INLAND. THIS WILL KEEP WINDS OUT OF THE SOUTHWEST THROUGH
SUN. SEAS WILL RUN 3 TO 5 FT BUT GIVEN THE EXTENDED PERIOD OF
WINDS AROUND 20 KT CANNOT RULE OUT SOME 6 FT SEAS...ESPECIALLY
WATERS NEAR 20 NM OPEN TO SOUTHWEST FETCH AND HEADLINES COULD BE
REQUIRED FOR AT LEAST A PORTION OF THE PERIOD.
&&
.ILM WATCHES/WARNINGS/ADVISORIES...
SC...HEAT ADVISORY UNTIL 8 PM EDT THIS EVENING FOR SCZ017-023-024-
032-033-039-053>056.
NC...HEAT ADVISORY UNTIL 8 PM EDT THIS EVENING FOR NCZ087-096-099-
105>110.
MARINE...NONE.
&&
$$
NEAR TERM...RGZ
SHORT TERM...III
LONG TERM...III
AVIATION...MRR
AREA FORECAST DISCUSSION
NWS BISMARCK ND
107 PM CDT WED JUN 24 2015
.UPDATE...
ISSUED AT 1253 PM CDT WED JUN 24 2015
AS THE FOCUS BEGINS TO SHIFT TO THE NEXT ROUND OF SHOWERS AND
THUNDERSTORMS...TIMING ONCE AGAIN NEEDED ADJUSTMENT ON THE BROKEN
LINE OF SHOWERS AND THUNDERSTORMS MOVING THROUGH THE U.S. 83
CORRIDOR.
UPDATE ISSUED AT 940 AM CDT WED JUN 24 2015
THE LATEST RADAR INDICATES CONVECTION IS MOVING FASTER THAN A
CONSENSUS OF THE LAST THREE HRRR RUNS. PRECIPITATION CHANCES WERE
UPDATED TO DO A BETTER JOB OF INDICATING THE MOST LIKELY TIMES FOR
PRECIPITATION AS A MID LEVEL SHORTWAVE RACES ACROSS THE STATE
TODAY. ANOTHER ROUND OF SHOWERS AND THUNDERSTORMS WILL COMMENCE AS
THE NEXT IN A LONG TRAIN OF SHORTWAVES MOVES FROM WESTERN MONTANA
INTO THE DAKOTAS AFTER MIDNIGHT TONIGHT...SO THAT WILL BE THE
SHORT TERM FOCUS FOR LATER FORECAST UPDATES.
UPDATE ISSUED AT 618 AM CDT WED JUN 24 2015
APPROACHING SHORT WAVE IS BRINGING SCATTERED SHOWERS/THUNDERSTORMS
ACROSS EASTERN MONTANA NUDGING INTO NORTHWEST NORTH DAKOTA. HAVE
ADJUSTED POPS A BIT TO ACCOUNT FOR THIS. HAVE ALSO ADJUSTED CLOUD
COVER WITH THE APPROACHING STORMS AND TO ACCOUNT FOR CLOUDS STREAMING
OFF THE ONGOING CONVECTION OVER SOUTHWEST/SOUTH CENTRAL SOUTH
DAKOTA.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 333 AM CDT WED JUN 24 2015
THUNDERSTORMS ONCE AGAIN HIGHLIGHT THE SHORT TERM.
WITH PERSISTENT ZONAL FLOW AND UPPER LEVEL JET PARKED OVER THE
REGION...AND LEE CYCLOGENESIS...DIURNAL THUNDERSTORMS WILL
CONTINUE TO BE POSSIBLE. SHORT TERM MODELS INDICATE THUNDERSTORM
DEVELOPMENT ACROSS EASTERN MONTANA AND WESTERN NORTH DAKOTA LATE
THIS MORNING INTO THE EARLY AFTERNOON HOURS...SPREADING ACROSS
CENTRAL NORTH DAKOTA LATE IN THE AFTERNOON AND EVENING HOURS. A
MOIST AND UNSTABLE BOUNDARY LAYER REMAINS ACROSS THE NORTHERN
PLAINS. WITH SOUTHERLY FLOW AT THE SURFACE AND STRONG WESTERLIES
ALOFT...SHEAR WILL CONTINUE TO BE VERY STRONG. SPC HAS NORTH
DAKOTA IN A MARGINAL RISK FOR SEVERE STORMS TODAY. WITH PERSISTENT
CAPE GREATER THAN 1K J/KG AND SHEAR GREATER THAN 50 KNOTS...ANY
STORMS THAT DO FORM COULD QUICKLY BECOME SUPERCELLULAR WITH THE
THREAT FOR DAMAGING WIND AND HAIL.
.LONG TERM...(THURSDAY THROUGH TUESDAY)
ISSUED AT 333 AM CDT WED JUN 24 2015
HIGHLIGHT IN THE LONG TERM WILL BE DIMINISHING THUNDERSTORM
CHANCES GOING INTO THE WEEKEND ALONG WITH A WARMING TREND.
WEST/NORTHWEST FLOW CONTINUES ON THURSDAY WHILE UPPER RIDGE OVER
THE WESTERN CONUS STARTS TO GRADUALLY INTENSIFY. VARIETY OF WEAK
DISTURBANCES CONTINUE TO MOVE THROUGH THE FLOW BRINGING
THUNDERSTORM CHANCES. MODEST SHEAR/INSTABILITY OVER MOST OF THE
AREA WILL KEEP SEVERE THREAT ON THE LOW SIDE...THOUGH OVER THE
SOUTHWEST 0-6 KM BULK SHEAR WILL APPROACH 40KTS WITH CAPE VALUES
~1-1.5 KJ/KG WILL BRING A MARGINAL SEVERE THREAT.
FOR FRIDAY RIDGE CONTINUES TO AMPLIFY WITH UPPER FLOW SHIFTING
MORE NORTHWESTERLY...THOUGH A FEW WEAK WAVES MOVING THROUGH MAY
BRING A FEW THUNDERSTORMS TO THE AREA.
FOR THE WEEKEND...RIDGE CONTINUES TO AMPLIFY. THIS WILL BRING DRY
CONDITIONS OVER OUR WEST...WITH POSSIBLY A FEW STORMS TOWARDS THE
EAST AS A FEW WEAK WAVES MOVE THROUGH. TEMPERATURES WILL WARM TO
ABOVE AVERAGE.
WARM TEMPERATURES CONTINUE INTO EARLY NEXT WEEK WITH OCCASIONAL
LOW THUNDERSTORMS CHANCES AS A FEW WEAK WAVES MOVE THROUGH
NORTHWESTERLY UPPER LEVEL FLOW.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z THURSDAY AFTERNOON)
ISSUED AT 1253 PM CDT WED JUN 24 2015
A BROKEN LINE OF CONVECTION STRETCHING FROM KMOT TO KBIS WILL
PROGRESS EAST TO KJMS TODAY. A SECOND ROUND OF SHOWERS AND
THUNDERSTORMS ARE FORECAST FOR TONIGHT...WITH LOW CONFIDENCE ON
TIMING IN TAFS INDICATED BY VCTS AT KBIS/KISN/KDIK.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...SCHECK
SHORT TERM...AJ
LONG TERM...JJS
AVIATION...SCHECK
AREA FORECAST DISCUSSION
NWS CLEVELAND OH
658 PM EDT WED JUN 24 2015
.SYNOPSIS...
HIGH PRESSURE OVER THE AREA WILL MOVE EAST INTO PENNSYLVANIA BY
MORNING. LOW PRESSURE WILL MOVE SLOWLY EAST ACROSS OHIO BY
THURSDAY EVENING AND SOUTHEAST OF THE AREA BY FRIDAY. ANOTHER WAVE
OF LOW PRESSURE WILL FORM ALONG A STALLED FRONT OVER THE LOWER
OHIO VALLEY ON FRIDAY AND TRACK INTO PENNSYLVANIA ON SUNDAY.
&&
.NEAR TERM /UNTIL 6 AM THURSDAY MORNING/...
A FAIRLY THICK CIRRUS DECK HAS OVERSPREAD THE AREA AND RAISED
CLOUD COVER IN THE FORECAST THROUGH THE EVENING. CLOUDS WILL
THIN SOME LATER THIS EVENING AND THEN INCREASE AGAIN OVERNIGHT AS
MID-LEVEL MOISTURE ADVECTION ARRIVES.
ALSO MADE SOME ADJUSTMENTS TO HIGH TEMPERATURES ON THURDSDAY.
ALTHOUGH CAN NOT ENTIRELY RULE OUT THE MORE NORTHERN TRACK OF THE
LOW EXHIBITED BY SOME OF THE HIGH RESOLUTION MODELS...THE 18Z
SUITE CONTINUES TO FAVOR A MORE SOUTHERN TRACK. LOOKS LIKE OUR
SOUTHERN TIER OF COUNTIES HAS A CHANCE OF APPROACHING THE 80
DEGREE MARK BUT THINK IT IS UNLIKELY TO REACH MUCH FARTHER NORTH
SO LOWERED HIGHS...ESPECIALLY FROM TOLEDO TO AKRON GIVEN THE
EXPECTED CLOUD COVER AND PRECIPITATION.
PREVIOUS DISCUSSION...
FAIR WEATHER THIS EVENING WILL END AS CLOUDS AND MOISTURE
INCREASE AFTER MIDNIGHT AS THE NEXT CONVECTIVE SYSTEM APPROACHES
FROM THE WEST. MODEL GUIDANCE IS RATHER CONSISTENT OVERNIGHT IN
BRINGING ABOUT A TENTH OF INCH OF QPF INTO THE TOL AREA BY 12Z AS
THE NOSE OF A LOW LEVEL JET AND ATTENDANT CONVERGENCE INCREASES
TOWARD MORNING. ALL CONVECTION ALLOWING MODELS PRODUCE SIMILAR QPF
AND PROGRESSION OF PRECIPITATION INTO NW OHIO. ELSEWHERE FAIR
WEATHER CLOUDS WILL DISSIPATE BEFORE SUNSET WITH JUST THICKENING
HIGH AND MID CLOUDS. THERE IS A SMALL CHANCE OF SHOWERS TOWARD
MORNING MAINLY WEST OF I-71. HAVE USED MAV MEX GUIDANCE FOR
OVERNIGHT LOW TEMPERATURES.
&&
.SHORT TERM /6 AM THURSDAY MORNING THROUGH SATURDAY NIGHT/...
MORE PRECIPITATION IS EXPECTED IN TWO ROUNDS. ONE ON THURSDAY AND
ANOTHER OVER THE WEEKEND.
FOR THURSDAY THE HIGH RESOLUTION MODELS TRACK THE SURFACE LOW FARTHER
NORTH ACROSS NORTHERN OHIO WHILE THE LARGE SCALE MODELS HAVE IT
FARTHER SOUTH. SPC HAS LIKELY MOVED THE SLIGHT RISK AREA FARTHER
NORTH TO ACKNOWLEDGE THE MORE NORTHERLY TRACK OF THE LOW AND HAS
NOW INCLUDED THE SOUTHERN PORTION OF REGION IN A SLIGHT RISK. WITH
LOW LCL HEIGHTS AND CLOSE PROXIMITY TO THE WARM FRONT WILL NEED TO
BE VERY AWARE OF ANY ROTATING STORMS. FARTHER NORTH MORE RAIN IS
EXPECTED AS THE REGION WILL BE IN THE ENTRANCE REGION OF THE UPPER
JET AS WELL AS IN THE NOSE OF THE LOW LEVEL JET. THIS ISENTROPIC
SETUP SHOULD PROVIDE MOD TO STRONG UPWARD MOTION FOR INCREASING
HUMID AIR. WOULD NOT RULE OUT 1-2 INCHES OF QPF ON ALREADY NEARLY
SATURATED SOIL. WE MAY HAVE MORE WATER/FLOOD ISSUES. WILL HOLD OFF
ON MENTIONING ANY FLOOD HEADLINES FOR NOW.
WITH THE REGION MORE IN THE WARM SECTOR...WILL RAISE MAX
TEMPERATURES AS DEPICTED BY THE DOWNSCALED NAM.
THE LOW WILL TRACK EAST THURSDAY EVENING AND THE ATTENDANT
TRAILING FRONT WILL STALL SOUTH OF THE REGION. WILL ATTEMPT TO
KEEP THE FORECAST DRY FOR FRIDAY BUT CAN NOT RULE OUT A BRIEF
LIGHT SHOWER IN THE SOUTH.
ANOTHER MORE SIGNIFICANT SHORT WAVE WILL PROGRESS ACROSS THE
REGION FRIDAY NIGHT AND DEEPEN AS IT PROGRESSES ACROSS THE REGION
OVER THE WEEKEND. THE SREF/GFS/ECMWF ALL TRACK A RATHER
STRONG/DEEP SURFACE LOW JUST SOUTH AND EAST OF THE CWA. THIS WILL
LIKELY PRODUCE MORE RAIN WHICH MAY BE HEAVY. THE SHOWERS WILL
SPREAD INTO THE REGION AFTER MIDNIGHT FRIDAY NIGHT AND CONTINUE
INTO SUNDAY. EXPECT THE HEAVIEST RAIN OVER THE CENTRAL AND EASTERN
PORTIONS OF THE AREA.
&&
.LONG TERM /SUNDAY THROUGH WEDNESDAY/...
AN UNSEASONABLY STRONG UPPER LOW WILL BE OVERHEAD THE
OHIO VALLEY THIS WEEKEND. ON SUNDAY THIS SYSTEM WILL BE SLOWLY
PULLING AWAY. GFSENS BRINGS H8 TEMPERATURES DOWN BELOW 10C. HIGHS
SUNDAY WILL BE SIGNIFICANTLY BELOW NORMAL...LIKELY NOT GETTING OUT OF
THE 60S ACROSS EASTERN OH/NW PA. WILL LINGER PRECIP CHANCES ACROSS
THE AREA UNTIL THAT SYSTEM FULLY DEPARTS. MONDAY WILL BE IN BETWEEN
SYSTEMS WITH SLIGHT RIDGING. THE NEXT SHORTWAVE OF NOTE WILL ARRIVE
WITH A COLD FRONT FOR TUESDAY...RE-ENFORCING THE EASTERN U.S.
TROUGH. THIS IS LATER THAN PREVIOUS FORECAST...BUT WITH STRONG AND
SLOWER WEEKEND SYSTEM THIS IS EXPECTED. SHOWERS AND THUNDERSTORMS
WILL BE ASSOCIATED WITH THIS FRONT. WEDNESDAY SHOULD BE A FAIR
WEATHER WITH CURRENT TIMING OF ALL OF THESE SYSTEMS.
&&
.AVIATION /18Z WEDNESDAY THROUGH MONDAY/...
A LOW WILL MOVE INTO OHIO BY LATE THU. WIDESPREAD SHRA AND SOME
TSRA ARE EXPECTED TO MOVE INTO TOL AND FDY TOWARD THE END OF THE
NIGHT AND SHOULD REACH CLE AROUND 9 TO 10 AM AND FINALLY YNG AND
MAYBE ERI ABOUT MIDDAY. THE RAP MODEL AND NOW THE HRRR ARE SHOWING
A SLOWER AND FURTHER SOUTHWARD PROGRESSION SO UNCERTAINTY WITH THE
FORECAST IS PRESENT. AREAS OF MVFR WILL LIKELY DEVELOP AFTER A FEW
HOURS OF RAIN AS THE LOWER LEVELS BECOME SATURATED. WINDS SHOULD
STAY LIGHT...GENERALLY UNDER 12 KNOTS THRU THU.
OUTLOOK...NON VFR LIKELY THU NIGHT INTO EARLY FRI IN SHRA THEN NON
VFR MAY LINGER ACROSS EASTERN OH/NW PA THE REST OF FRI. WIDESPREAD
NON VFR RETURNS FOR FRIDAY NIGHT THROUGH SUNDAY IN MORE WIDESPREAD
RAIN.
&&
.MARINE...
FAIR WEATHER AND A QUIET LAKE TONIGHT. AFTER THAT WEATHER
QUITE UNSETTLED. LOW PRESSURE WILL TRACK EAST ACROSS OHIO ON
THURSDAY...BRINGING WINDS AROUND TO THE NORTHEAST ON THE LAKE BY
THURSDAY EVENING. NORTHEAST WINDS WILL CONTINUE THROUGH FRIDAY AS
HIGH PRESSURE REMAINS NEARLY STATIONARY ACROSS THE CENTRAL GREAT
LAKES. SIGNIFICANT CHANGES FOR THE WEEKEND FORECAST WITH A TREND
TOWARD A STRONG LOW MOVING INTO THE OHIO VALLEY FRIDAY NIGHT AND
SLOWLY MOVING UP THE OHIO VALLEY THROUGH THE WEEKEND. THIS WOULD
CONTINUE AND STRENGTHEN THE NORTHEAST FLOW ON THE LAKE FOR SATURDAY.
STILL STRONG BUT MORE NORTHERLY WINDS ARE EXPECTED SUNDAY AS THE LOW
BEGINS TO PULL AWAY. SMALL CRAFT ADVISORIES WILL BE A CERTAINTY. WE
ARE TALKING 20 TO 30 KNOTS FOR A BIG CHUNK OF THE WEEKEND.
CONDITIONS SLOWLY IMPROVE ON MONDAY WITH HIGH PRESSURE CENTERED OVER
THE TN VALLEY.
&&
.CLE WATCHES/WARNINGS/ADVISORIES...
OH...NONE.
PA...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...LAPLANTE
NEAR TERM...KEC/LAPLANTE
SHORT TERM...LAPLANTE
LONG TERM...OUDEMAN
AVIATION...ADAMS
MARINE...OUDEMAN
AREA FORECAST DISCUSSION
NWS GREENVILLE-SPARTANBURG SC
459 PM EDT WED JUN 24 2015
.SYNOPSIS...
STRONG MID LEVEL HIGH PRESSURE WILL PERSIST ACROSS THE REGION
THROUGH THE REMAINDER OF THE WORK WEEK...MAINTAINING WELL ABOVE
NORMAL TEMPERATURES. A BROAD UPPER LEVEL TROF WILL MOVE OVER THE
REGION OVER THE WEEKEND RETURNING TEMPERATURES TO SEASONAL LEVELS BY
SUNDAY AND INCREASING CHANCES FOR WIDESPREAD SHOWERS AND
THUNDERSTORMS. A COOLER AND DRIER PATTERN WILL TAKE SHAPE AFTER A
FRONT PASSES EARLY IN THE WEEK BEFORE ANOTHER FRONTAL BOUNDARY
APPROACHES THE AREA LATER NEXT WEEK.
&&
.NEAR TERM /THROUGH THURSDAY/...
445 PM UPDATE...CLUSTERS OF CONVECTION ARE ONGOING OVER NE GA AND
THE SRN FACING BLUE RIDGE OF SW NC. GENERAL CONSENSUS FROM
CONVECTION ALLOWING GUIDANCE IS THAT THE ACTIVITY WILL PROPAGATE
SEWD OVER THE NEXT 2-3 HRS. SOME DEVELOPMENT OF SHOWERS OR TSTMS
OVER THE NC PIEDMONT AND ERN UPSTATE CANNOT BE RULED OUT...BUT THE
LOOK OF CUMULUS ON SATELLITE SUGGESTS SPARSE COVERAGE AT BEST. A
COUPLE OF LIGHT RETURNS HAVE BEEN SEEN ON RADAR IN THESE AREAS...BUT
MODEL PROGS OF WIDESPREAD SMALL CELLS DEVELOPING JUST LOOKS
OVERDONE. POPS HAVE BEEN REDUCED BASICALLY EAST OF I-26.
AS OF 230 PM...CUMULUS CLOUDS HAVE CAPPED THE TEMP RUN UP SOMEWHAT
THIS AFTERNOON PARTICULARLY IN THE GREENVILLE-SPARTANBURG AREA.
THEREFORE...DIALED BACK THE MAX TEMPS BY A 2-3 DEGREES THOSE AREAS.
THE RISE AT CLT HAS SLOWED AS WELL SO THEY SHOULD COME UP SHY OF
100. CONVECTION FIRING OVER FAR WESTERN NC AND NE GA AS EXPECTED.
LATEST HRRR USES THE SFC TROUGH LAYING ACROSS UPSTATE SC INTO
WESTERN NC TO DEVELOP SCT THUNDERSTORMS BY LATE AFTERNOON. WITH
CAPES BETWEEN 2000-3000J AND DCAPES >1000J A FEW WET DAMAGING
MICROBURSTS ARE LIKELY. THE CONVECTION SHOULD ASH OUT DURING THE
EVENING WITH THE LOSS OF HEATING.
FOR THE OVERNIGHT...IT WILL BE A MUGGY NIGHT WITH CLEAR TO PARTLY
CLOUDY CONDITIONS. MIN TEMPS WILL BE WELL ABOVE CLIMO WITH LOW TO
MID 70S OUTSIDE THE MOUNTAINS AND LOW TO MID 60S MOUNTAINS.
THURSDAY WILL BE ANOTHER HOT DAY AS THE UPPER HIGH TO THE WEST
BEGINS TO SLIP EASTWARD BUT WEAKEN SOMEWHAT. ALSO SUBTLE CHANGES
OCCUR AT THE SURFACE AS THE WEAK BOUNDARY ACROSS THE AREA IS
FORECAST TO MOVE NORTHEAST AS A LOW MOVES THROUGH THE OHIO VALLEY.
HENCE...THE AMOUNT OF FORCING FOR THUNDERSTORMS WILL BE SOMEWHAT
LESS WITH SOME DEGREE OF SYNOPTIC SUBSIDENCE. HOWEVER...FORECAST
SOUNDINGS SHOW CIN ERODING IN THE AFTERNOON TO WHERE WE EXPECT A FEW
UPDRAFTS TO BREAK THE CAP. HENCE...WILL CARRY ISOLATED TO SCATTERED
POPS OVER THE MOUNTAINS AND THE SOUTHERN PIEDMONT. THE OTHER CONCERN
WILL CONTINUE TO BE THE HEAT. HAVE GONE ON THE HIGH END OF THE
GUIDANCE ENVELOPE FOR MAX TEMPS ON FRIDAY WHICH IS WHAT THE
THICKNESS WOULD SUPPORT. DEWPOINTS WILL TRY TO MIX OUT SOME DURING
THE AFTERNOON...BUT PROBABLY NOT ENOUGH TO PRECLUDE AN HOUR OR TWO
OF APPARENT TEMPS REACHING 105 ACROSS PARTS OF THE UPSTATE. IF
CURRENT NUMBERS HOLD...MAY HAVE TO CONSIDER A HEAT ADVISORY FOR
PARTS OF NE GA...UPSTATE SC AND PERHAPS THE CLT AREA.
&&
.SHORT TERM /THURSDAY NIGHT THROUGH SATURDAY/...
AS OF 145 PM WEDNESDAY...THE BIG STORY OF THE SHORT TERM PERIOD WILL
BE THE SIGNIFICANT PATTERN CHANGE THAT IS ANTICIPATED...AS A
SIGNIFICANT SHORT WAVE DIVES OUT OF THE NORTHERN CONUS...AND CARVES
OUT A LONG WAVE TROUGH ACROSS THE EASTERN CONUS BY THE START OF THE
WEEKEND. SURFACE LOW PRESSURE TRACKING ALONG THE ASSOCIATED FRONTAL
ZONE...FROM THE TENN TO THE OHIO VALLEY IS EXPECTED TO ACTIVATE A
PSEUDO-WARM FRONT/E-W ORIENTED CONVERGENCE ZONE ACROSS THE REGION ON
FRIDAY...AND THIS COULD ACT AS AN ADDITIONAL FOCUS FOR CONVECTIVE
INITIATION ACROSS OUR AREA FRI AFTERNOON. HOWEVER...THERE ARE QUITE
A FEW MIXED SIGNALS IN THE GUIDANCE REGARDING HOW WIDESPREAD ANY
CONVECTION WILL BE DURING THE AFTERNOON. THE HIGHEST POPS (LIKELY)
WILL BE FOCUSED ACROSS THE NORTHERN ZONES...WHERE A MODEL CONSENSUS
SUGGESTS THE CONVERGENCE ZONE WILL RESIDE DURING PEAK HEATING...AND
ACROSS THE HIGH TERRAIN...WHERE THE COMBINATION OF TERRAIN EFFECTS
AND INCREASED CONVERGENCE SHOULD RESULT IN HIGHER THAN NORMAL
COVERAGE. DESPITE IMPROVING MID/UPPER FLOW RESPONDING TO HEIGHT
FALLS...SHEAR MAGNITUDE WILL REMAIN QUITE WEAK OWING TO
UNIDIRECTIONAL PROFILES. NEVERTHELESS...A FEW SEVERE STORMS WILL BE
POSSIBLE.
WITH HEIGHTS CONTINUING TO FALL AND AN APPROACHING FRONTAL ZONE...
GOOD CHANCES FOR CONVECTION ARE EXPECTED TO CONTINUE WELL INTO FRI
NIGHT...AND LIKELY POPS WILL ACTUALLY BE CARRIED THROUGH THE
OVERNIGHT HOURS...DUE TO THE POTENTIAL FOR PRE-FRONTAL CONVECTION
MOVING INTO THE FORECAST AREA...BUT ALSO DUE TO DEVELOPMENT OF AN
ANOMALOUSLY STRONG W/SW LOW LEVEL FLOW...WHICH COULD ALLOW FOR SOME
TERRAIN-INDUCED CONVECTION.
SATURDAY WILL FEATURE AMPLE GOOD SOURCES OF LIFT...WITH LOW LEVEL
CONVERGENCE ALONG THE FRONT...AND AN UPPER PATTERN SUPPORTIVE OF
UVV. HOWEVER...SATURDAY WILL BE THE MOST STABLE DAY OF THE WEEK AS
WELL...OWING TO THE LIKELIHOOD OF ABUNDANT MORNING CLOUD COVER AND
DEEP MOIST ADIABATIC LAPSE RATES. ON THE OTHER HAND...SHEAR WILL BE
RATHER IMPRESSIVE FOR LATE JUNE...ABOUT 30 KTS THROUGH A DEEP LAYER.
SOME UPSCALE ORGANIZATION COULD THEREFORE OCCUR IF POCKETS OF MORE
ROBUST INSTABILITY CAN BE REALIZED. LIKELY POPS WILL BE CARRIED
ACROSS THE MAJORITY OF THE AREA SAT AFTERNOON.
&&
.LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/...
AS OF 300 PM WEDNESDAY...THE MEDIUM RANGE BEGINS SATURDAY NIGHT
WITH A FRONTAL BOUNDARY APPROACHING THE FORECAST AREA. POPS WILL
REMAIN ELEVATED THROUGH EARLY SUNDAY BEFORE THE FRONT CLEARS THE
REGION AND DRIER AIR WORKS IN. THE PLEASANT DRIER AND UNSEASONABLY
COOL REGIME WILL PERSIST THROUGH MONDAY AND PERHAPS EARLY TUESDAY.
LOW-LEVEL FLOW TURNS SOUTHWESTERLY ON TUESDAY...ADVECTING SLIGHTLY
WARMER AND MORE MOIST AIR INTO THE CWA. ANOTHER FRONT APPROACHES
THE AREA TOWARDS THE END OF THE PERIOD. MODEL DISCREPANCIES ON
TIMING AND ASSOCIATED QPF AMOUNTS REMAIN SIGNIFICANT THOUGH
INCREASED POPS TOWARDS THE END OF THE PERIOD ARE LIKELY.
GIVEN ABUNDANT CLOUD COVER ASSOCIATED WITH THE INITIAL FRONTAL
PASSAGE...TEMPS WILL BE 5-10 DEGREES BELOW CLIMO ON SUNDAY AND
MONDAY. HEADING INTO TUESDAY TEMPS WILL RECOVER TO NEAR NORMAL
VALUES AND REMAIN NEAR NORMAL THROUGH THE END OF THE PERIOD.
&&
.AVIATION /21Z WEDNESDAY THROUGH MONDAY/...
AT KCLT...A WEAK FRONTAL TROUGH IN THE VICINITY OF THE AIRFIELD
WILL SERVE TO TRIGGER ISOLD TO WIDELY SCT TSRA IN UNSTABLE AIRMASS.
HENCE...WILL CARRY A TEMPO TSRA FROM 22-00Z THIS AFTERNOON.
OTHERWISE...VFR CUMULUS WILL DISSIPATE AFTER SUNSET. WINDS SHOULD
PREVAIL NORTHERLY BUT OCNL VARIABILITY IS POSSIBLE DUE TO THE
PROXIMITY OF THE TROUGH...AND ANY NEARBY TSRA WILL PRODUCE GUSTY
OUTFLOWS.
ELSEWHERE...AIRMASS IS QUITE UNSTABLE OUTSIDE THE MOUNTAINS THIS
AFTERNOON ALONG WITH A WEAK FRONTAL TROUGH EXTENDING FROM WESTERN
NC...THROUGH UPSTATE SC INTO NE GA. SCATTERED THUNDERSTORMS ARE
EXPECTED TO DEVELOP BY MID AFTERNOON. CAMS FAVOR WESTERN AREAS WITH
THE BEST COVERAGE...SO WILL CARRY A TEMPO TSRA AT KAND. WILL MENTION
VCTS AT GSP AND GMU. THE CHANCE OF TSRA TOO LOW TO MENTION AT AVL
AND HKY. EXPECT SOME FOG FORMATION EARLY THURSDAY MORNING WITH
GUIDANCE SUGGESTING MVFR RESTRICTIONS AT AVL AND HKY.
OUTLOOK...TSTM CHANCES WILL INCREASE LATE IN THE WEEK INTO THE
WEEKEND AS A COLD FRONT EVENTUALLY APPROACHES FROM THE NW. MORNING
RESTRICTIONS DUE TO FOG AND/OR STRATUS ARE POSSIBLE...PARTICULARLY
WHERE HEAVY RAIN FELL THE PREVIOUS DAY...AND IN THE MOUNTAIN RIVER
VALLEYS. BEHIND THE COLD FRONT...A MUCH DRYER AND COOLER AIRMASS
WILL OVERSPREAD THE REGION ON SUNDAY.
CONFIDENCE TABLE...
21-03Z 03-09Z 09-15Z 15-18Z
KCLT HIGH 100% HIGH 100% HIGH 100% HIGH 100%
KGSP HIGH 91% HIGH 100% HIGH 100% HIGH 100%
KAVL HIGH 100% HIGH 100% HIGH 100% HIGH 100%
KHKY HIGH 100% HIGH 100% HIGH 91% HIGH 100%
KGMU HIGH 100% HIGH 100% HIGH 100% HIGH 100%
KAND HIGH 100% HIGH 100% HIGH 91% HIGH 100%
THE PERCENTAGE REFLECTS THE NUMBER OF GUIDANCE MEMBERS AGREEING
WITH THE SCHEDULED TAF ISSUANCE FLIGHT RULE CATEGORY. COMPLETE HOURLY
EXPERIMENTAL AVIATION FORECAST CONSISTENCY TABLES AND ENSEMBLE FORECASTS
ARE AVAILABLE AT THE FOLLOWING LINK: (MUST BE LOWER CASE)
WWW.WEATHER.GOV/GSP/AVIATION_TABLES
&&
.CLIMATE...
RECORD MAXIMUM TEMPERATURES FOR THIS WEEK...WITH YEARS IN WHICH THE
VALUES WERE LAST REACHED.
WEDNESDAY JUNE 24...
AVL 94 1952
CLT 102 1930
GSP 100 1952
THURSDAY JUNE 25...
AVL 96 1952
CLT 102 1914
GSP 101 1952
&&
.GSP WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
NC...NONE.
SC...NONE.
&&
$$
SYNOPSIS...LEV
NEAR TERM...LG/WIMBERLEY
SHORT TERM...JDL
LONG TERM...JP/LEV
AVIATION...LG/WIMBERLEY
CLIMATE...GSP
AREA FORECAST DISCUSSION
NWS GREENVILLE-SPARTANBURG SC
346 PM EDT WED JUN 24 2015
.SYNOPSIS...
STRONG MID LEVEL HIGH PRESSURE WILL PERSIST ACROSS THE REGION
THROUGH THE REMAINDER OF THE WORK WEEK...MAINTAINING WELL ABOVE
NORMAL TEMPERATURES. A BROAD UPPER LEVEL TROF WILL MOVE OVER THE
REGION OVER THE WEEKEND RETURNING TEMPERATURES TO SEASONAL LEVELS BY
SUNDAY AND INCREASING CHANCES FOR WIDESPREAD SHOWERS AND
THUNDERSTORMS. A COOLER AND DRIER PATTERN WILL TAKE SHAPE AFTER A
FRONT PASSES EARLY IN THE WEEK BEFORE ANOTHER FRONTAL BOUNDARY
APPROACHES THE AREA LATER NEXT WEEK.
&&
.NEAR TERM /THROUGH THURSDAY/...
AS OF 230 PM...CUMULUS CLOUDS HAVE CAPPED THE TEMP RUN UP SOMEWHAT
THIS AFTERNOON PARTICULARLY IN THE GREENVILLE-SPARTANBURG AREA.
THEREFORE...DIALED BACK THE MAX TEMPS BY A 2-3 DEGREES THOSE AREAS.
THE RISE AT CLT HAS SLOWED AS WELL SO THEY SHOULD COME UP SHY OF
100. CONVECTION FIRING OVER FAR WESTERN NC AND NE GA AS EXPECTED.
LATEST HRRR USES THE SFC TROUGH LAYING ACROSS UPSTATE SC INTO
WESTERN NC TO DEVELOP SCT THUNDERSTORMS BY LATE AFTERNOON. WITH
CAPES BETWEEN 2000-3000J AND DCAPES >1000J A FEW WET DAMAGING
MICROBURSTS ARE LIKELY. THE CONVECTION SHOULD ASH OUT DURING THE
EVENING WITH THE LOSS OF HEATING.
FOR THE OVERNIGHT...IT WILL BE A MUGGY NIGHT WITH CLEAR TO PARTLY
CLOUDY CONDITIONS. MIN TEMPS WILL BE WELL ABOVE CLIMO WITH LOW TO
MID 70S OUTSIDE THE MOUNTAINS AND LOW TO MID 60S MOUNTAINS.
THURSDAY WILL BE ANOTHER HOT DAY AS THE UPPER HIGH TO THE WEST
BEGINS TO SLIP EASTWARD BUT WEAKEN SOMEWHAT. ALSO SUBTLE CHANGES
OCCUR AT THE SURFACE AS THE WEAK BOUNDARY ACROSS THE AREA IS
FORECAST TO MOVE NORTHEAST AS A LOW MOVES THROUGH THE OHIO VALLEY.
HENCE...THE AMOUNT OF FORCING FOR THUNDERSTORMS WILL BE SOMEWHAT
LESS WITH SOME DEGREE OF SYNOPTIC SUBSIDENCE. HOWEVER...FORECAST
SOUNDINGS SHOW CIN ERODING IN THE AFTERNOON TO WHERE WE EXPECT A FEW
UPDRAFTS TO BREAK THE CAP. HENCE...WILL CARRY ISOLATED TO SCATTERED
POPS OVER THE MOUNTAINS AND THE SOUTHERN PIEDMONT. THE OTHER CONCERN
WILL CONTINUE TO BE THE HEAT. HAVE GONE ON THE HIGH END OF THE
GUIDANCE ENVELOPE FOR MAX TEMPS ON FRIDAY WHICH IS WHAT THE
THICKNESS WOULD SUPPORT. DEWPOINTS WILL TRY TO MIX OUT SOME
DURING THE AFTERNOON...BUT PROBABLY NOT ENOUGH TO PRECLUDE AN HOUR
OR TWO OF APPARENT TEMPS REACHING 105 ACROSS PARTS OF THE UPSTATE.
IF CURRENT NUMBERS HOLD...MAY HAVE TO CONSIDER A HEAT ADVISORY FOR
PARTS OF NE GA...UPSTATE SC AND PERHAPS THE CLT AREA.
&&
.SHORT TERM /THURSDAY NIGHT THROUGH SATURDAY/...
AS OF 145 PM WEDNESDAY...THE BIG STORY OF THE SHORT TERM PERIOD WILL
BE THE SIGNIFICANT PATTERN CHANGE THAT IS ANTICIPATED...AS A
SIGNIFICANT SHORT WAVE DIVES OUT OF THE NORTHERN CONUS...AND CARVES
OUT A LONG WAVE TROUGH ACROSS THE EASTERN CONUS BY THE START OF THE
WEEKEND. SURFACE LOW PRESSURE TRACKING ALONG THE ASSOCIATED FRONTAL
ZONE...FROM THE TENN TO THE OHIO VALLEY IS EXPECTED TO ACTIVATE A
PSEUDO-WARM FRONT/E-W ORIENTED CONVERGENCE ZONE ACROSS THE REGION ON
FRIDAY...AND THIS COULD ACT AS AN ADDITIONAL FOCUS FOR CONVECTIVE
INITIATION ACROSS OUR AREA FRI AFTERNOON. HOWEVER...THERE ARE QUITE
A FEW MIXED SIGNALS IN THE GUIDANCE REGARDING HOW WIDESPREAD ANY
CONVECTION WILL BE DURING THE AFTERNOON. THE HIGHEST POPS (LIKELY)
WILL BE FOCUSED ACROSS THE NORTHERN ZONES...WHERE A MODEL CONSENSUS
SUGGESTS THE CONVERGENCE ZONE WILL RESIDE DURING PEAK HEATING...AND
ACROSS THE HIGH TERRAIN...WHERE THE COMBINATION OF TERRAIN EFFECTS
AND INCREASED CONVERGENCE SHOULD RESULT IN HIGHER THAN NORMAL
COVERAGE. DESPITE IMPROVING MID/UPPER FLOW RESPONDING TO HEIGHT
FALLS...SHEAR MAGNITUDE WILL REMAIN QUITE WEAK OWING TO
UNIDIRECTIONAL PROFILES. NEVERTHELESS...A FEW SEVERE STORMS WILL BE
POSSIBLE.
WITH HEIGHTS CONTINUING TO FALL AND AN APPROACHING FRONTAL ZONE...
GOOD CHANCES FOR CONVECTION ARE EXPECTED TO CONTINUE WELL INTO FRI
NIGHT...AND LIKELY POPS WILL ACTUALLY BE CARRIED THROUGH THE
OVERNIGHT HOURS...DUE TO THE POTENTIAL FOR PRE-FRONTAL CONVECTION
MOVING INTO THE FORECAST AREA...BUT ALSO DUE TO DEVELOPMENT OF AN
ANOMALOUSLY STRONG W/SW LOW LEVEL FLOW...WHICH COULD ALLOW FOR SOME
TERRAIN-INDUCED CONVECTION.
SATURDAY WILL FEATURE AMPLE GOOD SOURCES OF LIFT...WITH LOW LEVEL
CONVERGENCE ALONG THE FRONT...AND AN UPPER PATTERN SUPPORTIVE OF
UVV. HOWEVER...SATURDAY WILL BE THE MOST STABLE DAY OF THE WEEK AS
WELL...OWING TO THE LIKELIHOOD OF ABUNDANT MORNING CLOUD COVER AND
DEEP MOIST ADIABATIC LAPSE RATES. ON THE OTHER HAND...SHEAR WILL BE
RATHER IMPRESSIVE FOR LATE JUNE...ABOUT 30 KTS THROUGH A DEEP LAYER.
SOME UPSCALE ORGANIZATION COULD THEREFORE OCCUR IF POCKETS OF MORE
ROBUST INSTABILITY CAN BE REALIZED. LIKELY POPS WILL BE CARRIED
ACROSS THE MAJORITY OF THE AREA SAT AFTERNOON.
&&
.LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/...
AS OF 300 PM WEDNESDAY...THE MEDIUM RANGE BEGINS SATURDAY NIGHT
WITH A FRONTAL BOUNDARY APPROACHING THE FORECAST AREA. POPS WILL
REMAIN ELEVATED THROUGH EARLY SUNDAY BEFORE THE FRONT CLEARS THE
REGION AND DRIER AIR WORKS IN. THE PLEASANT DRIER AND UNSEASONABLY
COOL REGIME WILL PERSIST THROUGH MONDAY AND PERHAPS EARLY TUESDAY.
LOW-LEVEL FLOW TURNS SOUTHWESTERLY ON TUESDAY...ADVECTING SLIGHTLY
WARMER AND MORE MOIST AIR INTO THE CWA. ANOTHER FRONT APPROACHES
THE AREA TOWARDS THE END OF THE PERIOD. MODEL DISCREPANCIES ON
TIMING AND ASSOCIATED QPF AMOUNTS REMAIN SIGNIFICANT THOUGH
INCREASED POPS TOWARDS THE END OF THE PERIOD ARE LIKELY.
GIVEN ABUNDANT CLOUD COVER ASSOCIATED WITH THE INITIAL FRONTAL
PASSAGE...TEMPS WILL BE 5-10 DEGREES BELOW CLIMO ON SUNDAY AND
MONDAY. HEADING INTO TUESDAY TEMPS WILL RECOVER TO NEAR NORMAL
VALUES AND REMAIN NEAR NORMAL THROUGH THE END OF THE PERIOD.
&&
.AVIATION /20Z WEDNESDAY THROUGH MONDAY/...
AT KCLT...A WEAK FRONTAL TROUGH IN THE VICINITY OF THE AIRFIELD
WILL SERVE TO TRIGGER SCT TSRA AS AIRMASS IS QUITE UNSTABLE THIS
AFTERNOON. HENCE...WILL CARRY A TEMPO TSRA FROM 21-23Z THIS
AFTERNOON. OTHERWISE...VFR CUMULUS WILL DISSIPATE AFTER SUNSET.
ELSEWHERE...AIRMASS IS QUITE UNSTABLE OUTSIDE THE MOUNTAINS THIS
AFTERNOON ALONG WITH A WEAK FRONTAL TROUGH EXTENDING FROM WESTERN
NC...THROUGH UPSTATE SC INTO NE GA. SCATTERED THUNDERSTORMS ARE
EXPECTED TO DEVELOP BY MID AFTERNOON. CAMS FAVOR WESTERN AREAS WITH
THE BEST COVERAGE...SO WILL CARRY A TEMPO TSRA AT KAND. WILL MENTION
VCTS AT GSP AND GMU. THE CHANCE OF TSRA TOO LOW TO MENTION AT AVL
AND HKY. EXPECT SOME FOG FORMATION EARLY THURSDAY MORNING WITH
GUIDANCE SUGGESTING MVFR RESTRICTIONS AT AVL AND HKY.
OUTLOOK...TSTM CHANCES WILL INCREASE LATE IN THE WEEK INTO THE
WEEKEND AS A COLD FRONT EVENTUALLY APPROACHES FROM THE NW. MORNING
RESTRICTIONS DUE TO FOG AND/OR STRATUS ARE POSSIBLE...PARTICULARLY
WHERE HEAVY RAIN FELL THE PREVIOUS DAY...AND IN THE MOUNTAIN RIVER
VALLEYS. BEHIND THE COLD FRONT...A MUCH DRYER AND COOLER AIRMASS
WILL OVERSPREAD THE REGION ON SUNDAY.
CONFIDENCE TABLE...
19-01Z 01-07Z 07-13Z 13-18Z
KCLT HIGH 100% HIGH 100% HIGH 100% HIGH 100%
KGSP HIGH 86% HIGH 100% HIGH 100% HIGH 100%
KAVL HIGH 100% HIGH 100% HIGH 96% HIGH 100%
KHKY HIGH 100% HIGH 100% HIGH 93% HIGH 100%
KGMU HIGH 86% HIGH 100% HIGH 100% HIGH 100%
KAND HIGH 100% HIGH 100% HIGH 93% HIGH 100%
THE PERCENTAGE REFLECTS THE NUMBER OF GUIDANCE MEMBERS AGREEING
WITH THE SCHEDULED TAF ISSUANCE FLIGHT RULE CATEGORY. COMPLETE HOURLY
EXPERIMENTAL AVIATION FORECAST CONSISTENCY TABLES AND ENSEMBLE FORECASTS
ARE AVAILABLE AT THE FOLLOWING LINK: (MUST BE LOWER CASE)
WWW.WEATHER.GOV/GSP/AVIATION_TABLES
&&
.CLIMATE...
RECORD MAXIMUM TEMPERATURES FOR THIS WEEK...WITH YEARS IN WHICH THE
VALUES WERE LAST REACHED.
THURSDAY JUNE 25...
AVL 96 1952
CLT 102 1914
GSP 101 1952
&&
.GSP WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
NC...NONE.
SC...NONE.
&&
$$
SYNOPSIS...LEV
NEAR TERM...LG
SHORT TERM...JDL
LONG TERM...JP/LEV
AVIATION...LG
CLIMATE...
AREA FORECAST DISCUSSION
NWS GREENVILLE-SPARTANBURG SC
252 PM EDT WED JUN 24 2015
.SYNOPSIS...
STRONG MID LEVEL HIGH PRESSURE WILL PERSIST ACROSS THE REGION
THROUGH THE REMAINDER OF THE WORK WEEK...MAINTAINING WELL ABOVE
NORMAL TEMPERATURES. A BROAD UPPER LEVEL TROF WILL MOVE OVER THE
REGION OVER THE WEEKEND RETURNING TEMPERATURES TO SEASONAL LEVELS BY
SUNDAY AND INCREASING CHANCES FOR WIDESPREAD SHOWERS AND
THUNDERSTORMS. A COOLER AND DRIER PATTERN WILL TAKE SHAPE AFTER A
FRONT PASSES EARLY IN THE WEEK BEFORE ANOTHER FRONTAL BOUNDARY
APPROACHES THE AREA LATER NEXT WEEK.
&&
.NEAR TERM /THROUGH THURSDAY/...
AS OF 230 PM...CUMULUS CLOUDS HAVE CAPPED THE TEMP RUN UP SOMEWHAT
THIS AFTERNOON PARTICULARLY IN THE GREENVILLE-SPARTANBURG AREA.
THEREFORE...DIALED BACK THE MAX TEMPS BY A 2-3 DEGREES THOSE AREAS.
THE RISE AT CLT HAS SLOWED AS WELL SO THEY SHOULD COME UP SHY OF
100. CONVECTION FIRING OVER FAR WESTERN NC AND NE GA AS EXPECTED.
LATEST HRRR USES THE SFC TROUGH LAYING ACROSS UPSTATE SC INTO
WESTERN NC TO DEVELOP SCT THUNDERSTORMS BY LATE AFTERNOON. WITH
CAPES BETWEEN 2000-3000J AND DCAPES >1000J A FEW WET DAMAGING
MICROBURSTS ARE LIKELY. THE CONVECTION SHOULD ASH OUT DURING THE
EVENING WITH THE LOSS OF HEATING.
FOR THE OVERNIGHT...IT WILL BE A MUGGY NIGHT WITH CLEAR TO PARTLY
CLOUDY CONDITIONS. MIN TEMPS WILL BE WELL ABOVE CLIMO WITH LOW TO
MID 70S OUTSIDE THE MOUNTAINS AND LOW TO MID 60S MOUNTAINS.
THURSDAY WILL BE ANOTHER HOT DAY AS THE UPPER HIGH TO THE WEST
BEGINS TO SLIP EASTWARD BUT WEAKEN SOMEWHAT. ALSO SUBTLE CHANGES
OCCUR AT THE SURFACE AS THE WEAK BOUNDARY ACROSS THE AREA IS
FORECAST TO MOVE NORTHEAST AS A LOW MOVES THROUGH THE OHIO VALLEY.
HENCE...THE AMOUNT OF FORCING FOR THUNDERSTORMS WILL BE SOMEWHAT
LESS WITH SOME DEGREE OF SYNOPTIC SUBSIDENCE. HOWEVER...FORECAST
SOUNDINGS SHOW CIN ERODING IN THE AFTERNOON TO WHERE WE EXPECT A
FEW UPDRAFTS TO BREAK THE CAP. HENCE...WILL CARRY ISOLATED TO
SCATTERED POPS OVER THE MOUNTAINS AND THE SOUTHERN PIEDMONT. THE
OTHER CONCERN WILL CONTINUE TO BE THE HEAT. HAVE GONE ON THE HIGH
END OF THE GUIDANCE ENVELOPE FOR MAX TEMPS ON FRIDAY WHICH IS WHAT
THE THICKNESS WOULD SUPPORT. DEWPOINTS WILL TRY TO MIX OUT SOME
DURING THE AFTERNOON...BUT PROBABLY NOT ENOUGH TO PRECLUDE AN HOUR
OR TWO OF APPARENT TEMPS REACHING 105 ACROSS PARTS OF THE UPSTATE.
IF CURRENT NUMBERS HOLD...MAY HAVE TO CONSIDER A HEAT ADVISORY FOR
PARTS OF NE GA...UPSTATE SC AND PERHAPS THE CLT AREA.
&&
.SHORT TERM /THURSDAY NIGHT THROUGH SATURDAY/...
AS OF 145 PM WEDNESDAY...THE BIG STORY OF THE SHORT TERM PERIOD WILL
BE THE SIGNIFICANT PATTERN CHANGE THAT IS ANTICIPATED...AS A
SIGNIFICANT SHORT WAVE DIVES OUT OF THE NORTHERN CONUS...AND CARVES
OUT A LONG WAVE TROUGH ACROSS THE EASTERN CONUS BY THE START OF THE
WEEKEND. SURFACE LOW PRESSURE TRACKING ALONG THE ASSOCIATED FRONTAL
ZONE...FROM THE TENN TO THE OHIO VALLEY IS EXPECTED TO ACTIVATE A
PSEUDO-WARM FRONT/E-W ORIENTED CONVERGENCE ZONE ACROSS THE REGION ON
FRIDAY...AND THIS COULD ACT AS AN ADDITIONAL FOCUS FOR CONVECTIVE
INITIATION ACROSS OUR AREA FRI AFTERNOON. HOWEVER...THERE ARE QUITE
A FEW MIXED SIGNALS IN THE GUIDANCE REGARDING HOW WIDESPREAD ANY
CONVECTION WILL BE DURING THE AFTERNOON. THE HIGHEST POPS (LIKELY)
WILL BE FOCUSED ACROSS THE NORTHERN ZONES...WHERE A MODEL CONSENSUS
SUGGESTS THE CONVERGENCE ZONE WILL RESIDE DURING PEAK HEATING...AND
ACROSS THE HIGH TERRAIN...WHERE THE COMBINATION OF TERRAIN EFFECTS
AND INCREASED CONVERGENCE SHOULD RESULT IN HIGHER THAN NORMAL
COVERAGE. DESPITE IMPROVING MID/UPPER FLOW RESPONDING TO HEIGHT
FALLS...SHEAR MAGNITUDE WILL REMAIN QUITE WEAK OWING TO
UNIDIRECTIONAL PROFILES. NEVERTHELESS...A FEW SEVERE STORMS WILL BE
POSSIBLE.
WITH HEIGHTS CONTINUING TO FALL AND AN APPROACHING FRONTAL ZONE...
GOOD CHANCES FOR CONVECTION ARE EXPECTED TO CONTINUE WELL INTO FRI
NIGHT...AND LIKELY POPS WILL ACTUALLY BE CARRIED THROUGH THE
OVERNIGHT HOURS...DUE TO THE POTENTIAL FOR PRE-FRONTAL CONVECTION
MOVING INTO THE FORECAST AREA...BUT ALSO DUE TO DEVELOPMENT OF AN
ANOMALOUSLY STRONG W/SW LOW LEVEL FLOW...WHICH COULD ALLOW FOR SOME
TERRAIN-INDUCED CONVECTION.
SATURDAY WILL FEATURE AMPLE GOOD SOURCES OF LIFT...WITH LOW LEVEL
CONVERGENCE ALONG THE FRONT...AND AN UPPER PATTERN SUPPORTIVE OF
UVV. HOWEVER...SATURDAY WILL BE THE MOST STABLE DAY OF THE WEEK AS
WELL...OWING TO THE LIKELIHOOD OF ABUNDANT MORNING CLOUD COVER AND
DEEP MOIST ADIABATIC LAPSE RATES. ON THE OTHER HAND...SHEAR WILL BE
RATHER IMPRESSIVE FOR LATE JUNE...ABOUT 30 KTS THROUGH A DEEP LAYER.
SOME UPSCALE ORGANIZATION COULD THEREFORE OCCUR IF POCKETS OF MORE
ROBUST INSTABILITY CAN BE REALIZED. LIKELY POPS WILL BE CARRIED
ACROSS THE MAJORITY OF THE AREA SAT AFTERNOON.
&&
.LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/...
AS OF 3 AM WEDNESDAY...SIGNIFICANT PATTERN CHANGE WILL SETTLE OVER
THE REGION THIS WEEKEND AND SHOULD REMAIN THROUGH THE EXTENDED
PERIOD. MODELS INDICATE THAT THE AXIS OF A L/W TROUGH WILL SWEEP
ACROSS THE REGION THIS WEEKEND...WITH A SECONDARY WAVE EXPECTED TO
CROSS THE APPALACHIANS ON TUESDAY. AT THE SFC...THE CENTER OF A
DEEPENING LOW WILL MOVE FROM THE OHIO RIVER VALLEY ON SATURDAY TO
SOUTHERN NY BY SUNDAY EVENING. A COLD FRONT SHOULD PUSH ACROSS THE
REGION LATE SATURDAY AFTERNOON AND EVENING. THE ENVIRONMENT AHEAD OF
THE FRONT WILL FEATURE WIDESPREAD INSTABILITY AND WEAK
SHEAR...POSSIBLY SUPPORTING A BAND OF TSRA SAT AFTERNOON. I WILL
FORECAST CATE COVERAGE NEAR THE TN LINE...WITH GENERALLY LIKELY POPS
ACROSS THE REST OF THE CWA. DRIER AIR WILL BUILD ACROSS THE REGION
ON SUNDAY...RESULTING IN FALLING POP VALUES. I WILL FORECAST
PRIMARILY DIURNAL POPS ACROSS THE REGION MON AND TUES. TEMPERATURES
THROUGH THE EXTENDED ARE FORECAST TO RANGE FROM BELOW NORMAL THIS
WEEKEND TO NEAR NORMAL BY TUESDAY.
&&
.AVIATION /19Z WEDNESDAY THROUGH MONDAY/...
AT KCLT...A WEAK FRONTAL TROUGH IN THE VICINTY OF THE AIRFIELD WILL
SERVE TO TRIGGER SCT TSRA AS AIRMASS IS QUITE UNSTABLE THIS
AFTERNOON. HENCE...WILL CARRY A TEMPO TSRA FROM 21-23Z THIS
AFTERNOON. OTHERWISE...VFR CUMULUS WILL DISSIPATE AFTER SUNSET.
ELSEWHERE...AIRMASS IS QUITE UNSTABLE OUTSIDE THE MOUNTAINS THIS
AFTERNOON ALONG WITH A WEAK FRONTAL TROUGH EXTENDING FROM WESTERN
NC...THROUGH UPSTATE SC INTO NE GA. SCATTERED THUNDERSTORMS ARE
EXPECTED TO DEVELOP BY MID AFTERNOON. CAMS FAVOR WESTERN AREAS WITH
THE BEST COVERAGE...SO WILL CARRY A TEMPO TSRA AT KAND. WILL MENTION
VCTS AT GSP AND GMU. THE CHANCE OF TSRA TOO LOW TO MENTION AT AVL
AND HKY. EXPECT SOME FOG FORMATION EARLY THURSDAY MORNING WITH
GUIDNACE SUGGESTING MVFR RESTRICTIONS AT AVL AND HKY.
OUTLOOK...TSTM CHANCES WILL INCREASE LATE IN THE WEEK INTO THE
WEEKEND AS A COLD FRONT EVENTUALLY APPROACHES FROM THE NW. MORNING
RESTRICTIONS DUE TO FOG AND/OR STRATUS ARE POSSIBLE...PARTICULARLY
WHERE HEAVY RAIN FELL THE PREVIOUS DAY...AND IN THE MOUNTAIN RIVER
VALLEYS. BEHIND THE COLD FRONT...A MUCH DRYER AND COOLER AIRMASS
WILL OVERSPREAD THE REGION ON SUNDAY.
CONFIDENCE TABLE...
19-01Z 01-07Z 07-13Z 13-18Z
KCLT HIGH 100% HIGH 100% HIGH 100% HIGH 100%
KGSP HIGH 86% HIGH 100% HIGH 100% HIGH 100%
KAVL HIGH 100% HIGH 100% HIGH 96% HIGH 100%
KHKY HIGH 100% HIGH 100% HIGH 93% HIGH 100%
KGMU HIGH 86% HIGH 100% HIGH 100% HIGH 100%
KAND HIGH 100% HIGH 100% HIGH 93% HIGH 100%
THE PERCENTAGE REFLECTS THE NUMBER OF GUIDANCE MEMBERS AGREEING
WITH THE SCHEDULED TAF ISSUANCE FLIGHT RULE CATEGORY. COMPLETE HOURLY
EXPERIMENTAL AVIATION FORECAST CONSISTENCY TABLES AND ENSEMBLE FORECASTS
ARE AVAILABLE AT THE FOLLOWING LINK: (MUST BE LOWER CASE)
WWW.WEATHER.GOV/GSP/AVIATION_TABLES
&&
.CLIMATE...
RECORD MAXIMUM TEMPERATURES FOR THIS WEEK...WITH YEARS IN WHICH THE
VALUES WERE LAST REACHED.
WEDNESDAY JUNE 24...
AVL 94 1952
CLT 102 1930
GSP 100 1952
THURSDAY JUNE 25...
AVL 96 1952
CLT 102 1914
GSP 101 1952
&&
.GSP WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
NC...NONE.
SC...NONE.
&&
$$
SYNOPSIS...LEV
NEAR TERM...LG
SHORT TERM...JDL
LONG TERM...JP/LEV
AVIATION...LG
CLIMATE...
AREA FORECAST DISCUSSION
NWS MILWAUKEE/SULLIVAN WI
352 PM CDT WED JUN 24 2015
.SHORT TERM...
TONIGHT... FORECAST CONFIDENCE MEDIUM.
CONVECTION ASSOCIATED WITH THE LOW LEVEL JET /LLJ/... SHORTWAVE
ENERGY AND UPPER LEVEL DIVERGENCE OVER CENTRAL IOWA WILL CONTINUE TO
MOVE ESE THROUGH NORTHERN IL. ONLY LIGHT SHOWERS... IF ANYTHING...
ARE EXPECTED TO REACH SOUTHERN WI FROM LATE AFTERNOON THROUGH EARLY
EVENING.
THE LLJ IS EXPECTED TO INTENSIFY OVER SOUTH CENTRAL IOWA THIS
EVENING AS IT VEERS EAST. THE NOSE OF THE LLJ IS NOW EXPECTED TO
REMAIN OVER EAST CENTRAL IOWA OR SOUTH... ALONG WITH THE 850MB WARM
FRONT. THIS IS FARTHER SOUTH THAN MANY OF THE PREVIOUS MODEL RUNS.
THUNDERSTORMS ARE ANTICIPATED TO FIRE UP ALONG THE SURFACE WARM
FRONT OVER CENTRAL IOWA WITH THE INCREASING LLJ LATE THIS EVENING
PER THE HRRR AND THEN SLIDE EAST THROUGH CENTRAL IL.
KEPT CHANCE FOR SHOWERS AND THUNDERSTORMS ACROSS SOUTHERN WI DUE TO
THE VICINITY OF THE NOSE OF THE LLJ... UPPER DIVERGENCE WITH THE
RIGHT ENTRANCE REGION OF THE UPPER JET... AND WEAK VORTICITY
ADVECTION. ELEVATED INSTABILITY WILL REMAIN WEAK WITH LESS THAN 500
J/KG CAPE. NOT EXPECTING HEAVY RAIN TRAINING OVER AN AREA FOR A LONG
PERIOD OF TIME. NOT EXPECTING SEVERE WEATHER ALTHOUGH SPC HAS NOT
TRIMMED SOUTHERN WI OUT OF THE SLIGHT RISK YET THIS AFTERNOON.
.THURSDAY... FORECAST CONFIDENCE MEDIUM.
LIGHT SURFACE WINDS AND LINGERING LOW LEVEL MOISTURE SHOULD LEAD TO
LOW CLOUDS ACROSS SOUTHERN WI EARLY THURSDAY MORNING. THESE SHOULD
SLOWLY SCOUR OUT THROUGH THE DAY. LIGHT RAIN SHOWERS MAY LINGER WITH
THIS MOISTURE THROUGH THE MORNING HOURS BUT CONFIDENCE IS LOW... SO
ONLY HAVE SLIGHT CHANCE POPS IN FORECAST. AFTERNOON SHOULD BE DRY
WITH INCREASING SUNSHINE AND HIGHS BACK UP AROUND 80 EXCEPT NEAR THE
LAKE.
.LONG TERM...
.FRIDAY AND SATURDAY...
NW FLOW ALOFT WILL TURN MORE CYCLONIC AS A SHARP UPPER LEVEL TROF
DIVES SOUTH ACROSS THE REGION ON FRIDAY AND SATURDAY. HOWEVER...THE
FLOW OVER WISCONSIN DURING THIS PERIOD WILL BE WEAK...AND THERE WILL
BE LITTLE FORCING FOR ASCENT IN THE UPPER LEVELS. IN THE MID-
LEVELS...WE WILL BE ON THE COOL AND DRY SIDE OF A FRONT EXTENDING
WEST FROM THE LOW THAT WILL PASS ON THURSDAY. A SECOND LOW WILL
APPROACH THE STATE FROM THE SOUTHWEST ON FRIDAY...BUT SHOULD STAY TO
THE SOUTH OF THE STATE THANKS TO THE FRONT IN PLACE. GFS AND EURO DO
BRING SOME LIGHT PRECIP INTO THE AREA ON FRIDAY AFTERNOON...BUT
CHOSE TO REMAIN DRY AT THIS POINT GIVEN THE MEAGER ASCENT AND
MOISTURE.
BY FRIDAY EVENING...THE UPPER LEVEL TROF AXIS WILL HAVE PASSED TO
THE EAST OF THE STATE...PLACING WISCONSIN UNDER NORTHERLY FLOW
ALOFT. THE MID AND LOW LEVELS WILL DRY OUT...MAKING FOR A VERY NICE
DAY ON SATURDAY.
.SUNDAY THROUGH WEDNESDAY...
WISCONSIN WILL BE FIRMLY ENTRENCHED IN NNW FLOW ALOFT AS A DEEP
UPPER LEVEL TROF STALLS OVER THE EASTERN CONUS AND A ROBUST
RIDGE/CLOSED HIGH BUILDS INTO THE WESTERN CONUS. THIS PATTERN WILL
PERSIST THROUGH THE PERIOD AS A FEW SHORTWAVE TROFS PASS ACROSS THE
STATE REINFORCING THE TROF OVER THE EAST. THOSE SHORTWAVES WILL
PROVIDE THE LIFT FOR RAIN CHANCES EACH DAY IN THIS PERIOD. THE NW
FLOW SHOULD KEEP TEMPS SLIGHTLY BELOW NORMAL THROUGH THIS PERIOD.
&&
.AVIATION/00Z TAFS/...
VFR CONDITIONS ARE EXPECTED THROUGH LATE EVENING. A COMPLEX OF
STORMS IS THEN EXPECTED TO TRACK ACROSS CENTRAL ILLINOIS OVERNIGHT.
SOUTHERN WI SHOULD GET CLIPPED BY SHOWERS AND A FEW THUNDERSTORMS ON
THE NORTHERN SIDE OF THE MAIN AREA OF CONVECTION. MVFR CONDITIONS
CAN BE EXPECTED WITHIN ANY THUNDERSTORMS.
IFR CONDITIONS WITH CIGS/VSBYS ARE POSSIBLE LATER TONIGHT AS THE
CONVECTION MOVES OFF WHILE THE ATMOSPHERE REMAINS VERY MOIST WITHIN
A VERY WEAK LOW LEVEL FLOW. VFR EXPECTED BY THU AFTERNOON.
&&
.MKX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
LM...NONE.
&&
$$
TONIGHT/THURSDAY AND AVIATION/MARINE...MRC
THURSDAY NIGHT THROUGH WEDNESDAY...BSH
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
217 PM CDT WED JUN 24 2015
.SHORT TERM...(TONIGHT THROUGH THURSDAY NIGHT)
ISSUED AT 217 PM CDT WED JUN 24 2015
WATER VAPOR IMAGERY AND RAP 500MB ANALYSIS THIS AFTERNOON SHOWS
WEST/NORTHWEST FLOW ACROSS THE DAKOTAS INTO THE GREAT LAKES REGION.
WITHIN THIS FLOW A COUPLE OF WEAK EMBEDDED SHORT WAVE TROUGHS WERE
ACROSS NORTHERN MN AND ACROSS EASTERN NEB/WESTERN IA. STRONG TO
SEVERE THUNDERSTORMS WERE TIED TO SHORTWAVE COMING ACROSS EASTERN
NEB/WESTERN IA WHILE THE CONVECTION ACROSS NORTHERN MN/UPPER MI WAS
TIED MORE TO CONVERGENCE OF LAKE BREEZE FRONT. OUR AREA WAS IN
BETWEEN THESE TWO SYSTEM...HIGH AND DRY FOR NOW. UNDER PARTLY CLOUDY
SKIES...TEMPERATURES RANGED FROM THE MIDDLE 70S TO THE LOWER 80S.
FOR TONIGHT...WILL SEE THAT MID-LEVEL SHORTWAVE AND MCV ACROSS IA
PASS SOUTH OF THE AREA EARLY THIS EVENING. MODELS THEN SHOW RETURN
850MB FLOW BEHIND THIS SYSTEM LATER THIS EVENING INTO THE OVERNIGHT
HOURS. THIS PUSHES A WARM FRONT THAT WAS OVER NORTHERN KS INTO
NORTHERN MO...NORTHWARD NEAR I-80. 850MB MOISTURE TRANSPORT LOOKS TO
REGENERATE A BAND OF ELEVATED SHOWERS AND THUNDERSTORMS NORTH OF THE
WARM FRONT...POSSIBLE GRAZING OUR NORTHEAST IA COUNTIES. LATEST WRF
RUNS KEEP CONVECTION JUST TO OUR SOUTH WHILE COARSER DETERMINISTIC
NAM/GFS/ECMWF MODELS SUGGESTING CONVECTION REACHING INTO NORTHEAST
IA AND SOUTHWEST WI. WILL KEEP LIKELY POPS CONFINED TO FAR SOUTHERN
FAYETTE/CLAYTON COUNTIES IN NORTHEAST IA AND FAR SOUTHER GRANT
COUNTY IN WI...TAPERING OFF RAPIDLY TO SLIGHT CHANCE POPS
ALONG/SOUTH OF I-90. HIGHER CAPE AXIS STAYS SOUTH OF THE AREA
THROUGH TONIGHT...SO NOT ANTICIPATING ANY SEVERE WEATHER IN OUR
FORECAST AREA...BUT WILL CONTINUE TO MAINTAIN A WATCHFUL EYE IN CASE
THE WARM FRONT/CAPE POOL SURGES FARTHER NORTHWARD THAN ANTICIPATED.
ALSO...WILL HAVE TO KEEP AN EYE ON THE SHOWERS/STORMS ACROSS
NORTHERN WI OVERNIGHT AS THAT WEAK MID-LEVEL TROUGH SWINGS THROUGH.
NOT MUCH WORKING FOR IT OTHER THAN STEEPER MID-LEVEL LAPSE
RATES...BUT NO SURFACE CONVERGENCE OR TRIGGER. IN FACT...MOST OF THE
WRF MODELS SHOW A WEAKENING TREND AFTER SUNSET WITH LOSS OF HEATING.
THURSDAY LOOKS FAIRLY QUIET AND COOLER THAN NORMAL AS NORTHWEST FLOW
ALOFT DOMINATES THE REGION. WITH SURFACE HIGH PRESSURE OVER LAKE
SUPERIOR PUMPING DRIER NORTHEAST FLOW INTO THE AREA...THINKING
MODELS ARE OVERDONE ON CONVECTION. LOOKS LIKE A LOT OF CUMULUS...BUT
ANY SHOWER/THUNDER SHOULD REMAIN CONFINED TO FAR NORTHERN WI/U.P. IN
STEEPER LAPSE RATES AND CLOSER TO ANY LAKE BREEZE CONVERGENCE ZONES.
OTHERWISE...LOOK FOR HIGHS GENERALLY IN THE 75-80 DEGREE RANGE.
FOR THURSDAY NIGHT...NORTHWEST FLOW DROPS ANOTHER MID-LEVEL
TROUGH/PV-ADVECTION ACROSS MN INTO IA WITH A SURFACE TROUGH IN
PLACE. THIS LOOKS TO PRODUCE A FEW SHOWERS/ISOLATED STORMS WEST OF
THE MISSISSIPPI RIVER. LOOK FOR OVERNIGHT TEMPERATURES DROPPING INTO
THE MID 50S TO THE LOWER 60S.
.LONG TERM...(FRIDAY THROUGH WEDNESDAY)
ISSUED AT 217 PM CDT WED JUN 24 2015
WILL STILL SEE A SLIGHT CHANCE OF SHOWERS AND ISOLATED THUNDERSTORMS
MAINLY WEST OF THE MISSISSIPPI RIVER FRIDAY AS THE MID-LEVEL TROUGH
CONTINUES TO ROTATE SOUTHEAST ACROSS THAT AREA. OTHERWISE...PLAN ON
A PARTLY SUNNY DAY DOMINATED WITH DECENT CUMULUS FIELD WITH HIGHS
ONLY TOPPING OFF IN THE LOWER/MIDDLE 70S.
FRIDAY NIGHT THROUGH SATURDAY LOOK DRY AS A WEAK RIDGE OF HIGH
PRESSURE BUILDS INTO THE REGION. LOOK FOR HIGHS IN THE 75-80 DEGREE
RANGE.
THE REST OF THE WEEKEND INTO MID-NEXT WEEK IS DOMINATED WITH MUDDLED
NORTHWEST FLOW ALOFT WITH EMBEDDED SHORTWAVE TROUGH ENERGY. AS A
RESULT...PLAN ON PERIODIC ON/OFF SHOWER AND THUNDERSTORM CHANCES
WITH TEMPERATURES REMAINING BELOW NORMAL. LOOK FOR HIGHS IN THE
MIDDLE/UPPER 70S WITH LOWS IN THE MIDDLE 50S TO THE LOWER 60S.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z THURSDAY AFTERNOON)
ISSUED AT 1215 PM CDT WED JUN 24 2015
WARM FRONT OF INTEREST FOR CONVECTION LATE THIS AFTERNOON AND
TONIGHT REMAINS IN NORTHERN MO EARLY THIS AFTERNOON. CONVECTION
EARLY THIS AFTERNOON CONFINED TO FAR EASTERN NEB AND SOUTHERN 2/3 OF
IA...MOVING STEADILY EAST. THIS CONVECTION WILL KEEP THE FRONT FROM
MOVING NORTH THRU THE AFTERNOON...WITH LITTLE MORE THAN SCT DIURNAL
CUMULUS AND GOOD VFR EXPECTED AT THE TAF SITES THRU EARLY THIS
EVENING. STILL A SHRA/TSRA CHANCE LATER THIS EVENING AND OVERNIGHT
AS A SURGE OF MOISTURE PUSHES NORTHEAST OVER THE WARM FRONT. APPEARS
THE BULK OF THIS WILL STAY SOUTH OF THE MN/IA BORDER AND LEFT TAFS
FREE OF A SHRA/TSRA MENTION TONIGHT BUT DID INCLUDE SOME 3500-4500
FT CIGS OVERNIGHT. SFC LOW PASSES ACROSS IA TONIGHT WITH DRIER
NORTHEAST TO NORTH FLOW AND GOOD VFR SPREADING ACROSS THE AREA THU.
&&
.HYDROLOGY...
ISSUED AT 217 PM CDT WED JUN 24 2015
RIVERS ARE RECEDING. SOME MINOR FLOODING REMAINS ALONG THE CEDAR
RIVER AT CHARLES CITY...BUT THE RIVER IS FORECAST TO FALL BELOW
STAGE THIS AFTERNOON. REFER TO THE LATEST FLOOD STATEMENTS FOR THE
LATEST STAGES AND FORECAST.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...DAS
LONG TERM....DAS
AVIATION.....RRS
HYDROLOGY....DAS