Forecast Discussions mentioning any of
"HRRR" "RAP" "RR" "RUC13" "RUC" received at GSD on 07/23/14
AREA FORECAST DISCUSSION...UPDATED
NWS RENO NV
1029 AM PDT MON JUL 21 2014
.UPDATE...
STRONG DAYTIME HEATING AS A RESULT OF CLEARING THIS MORNING FROM
THE SIERRA FRONT SOUTHWARD HAS ALLOWED FOR DESTABILIZATION OF THE
ATMOSPHERE AND DEVELOPMENT OF CUMULUS AT MID MORNING. FURTHER
DESTABILIZATION AND INCOMING UPPER JET WILL FOCUS THUNDERSTORMS IN
THESE AREAS EARLY THIS AFTERNOON BEFORE ACTIVITY BEGINS TO PUSH
OFF THE NORTHERN SIERRA INTO WESTERN NV BETWEEN HIGHWAYS 395 AND
95 LATER IN THE AFTERNOON. STORM MOTIONS ARE GOING TO BE FASTER
TODAY WHICH SHOULD LIMIT THE FLASH FLOOD POTENTIAL. HOWEVER,
STRONGER MID LEVEL FLOW AND ABUNDANT MOISTURE/INSTABILITY SUGGEST
STORMS WILL STILL HAVE DECENT VERTICAL DEVELOPMENT AND BE CAPABLE
OF STRONG WIND GUSTS OVER 50 MPH AND HAIL UP TO 1 INCH IN
DIAMETER. UPDATED THE FORECAST TO EXTEND SCATTERED COVERAGE OF
POPS FURTHER SOUTH AND ALSO INTO THE EVENING. HOHMANN
&&
.PREVIOUS DISCUSSION... /ISSUED 535 AM PDT MON JUL 21 2014/
UPDATE...
CLOUD TOPS CONTINUE TO COOL OVER WRN NV AND A SMALL PART OF NE CA.
THIS IS INDICATIVE OF INCREASING LIFT AS THE DEFORMATION AXIS OVER
THE AREA REMAINS IN PLACE AND APPEARS TO BE STRENGTHENING A BIT.
WE HAVE SEEN A FEW LIGHTNING STRIKES OVER THE LAST HOUR NORTH OF
GERLACH AND WITH COOLING CLOUD TOPS IT IS VERY POSSIBLE THAT A FEW
MORE STRIKES WILL DEVELOP. RADAR IMAGERY SHOWS THE AREA OF HIGHEST
RETURNS HAS NARROWED A BIT...BUT IT IS UNDER THE AREA OF COOLING
CLOUD TOPS. WILL BUMP UP POPS FROM NW PERSHING COUNTY INTO SIERRA
AND NEVADA COUNTIES IN ERN CA EARLY THIS MORNING. WITH A FAIRLY
CLEAR SKY OVER THE SRN 1/3 OF THE FORECAST AREA...THE THINKING IS
THAT CONVECTIVE DEVELOPMENT MAY BEGIN NEAR THE INTERFACE OF THE
CLOUD COVER TO THE NORTH AND CLEARING TO THE SOUTH BY LATE MORNING
OR EARLY AFTERNOON. HAVE EXPANDED SCATTERED COVERAGE A BIT
FARTHER SOUTH TO ACCOUNT FOR THAT POSSIBILITY THIS AFTERNOON. 20
PREVIOUS DISCUSSION... /ISSUED 338 AM PDT MON JUL 21 2014/
SYNOPSIS...
SCATTERED SHOWERS AND THUNDERSTORMS WILL REDEVELOP TODAY AS A MOIST
AND UNSTABLE AIR MASS REMAINS IN PLACE. STRONG STORMS WILL BE
POSSIBLE THIS AFTERNOON AND EVENING. ISOLATED THUNDERSTORMS ARE
POSSIBLE AGAIN TUESDAY AS LOW PRESSURE LIFTS NORTH ACROSS
CALIFORNIA. DRIER AND LOCALLY BREEZY CONDITIONS ARE EXPECTED BY
MID WEEK, FOLLOWED BY A WARMING TREND BY NEXT WEEKEND.
SHORT TERM...
RAIN SHOWERS CONTINUE ACROSS GENERALLY FROM INTERSTATE 80
NORTHWARD INTO NORTHEAST CA-NORTHWEST NV. THIS ACTIVITY MAY
PERSIST THROUGH THIS MORNING WITH SHORT RANGE HRRR MODEL GUIDANCE
INDICATING THE MAIN BAND OF SHOWERS DRIFTING SLOWLY NORTHWARD INTO
PLUMAS, LASSEN AND NORTHERN WASHOE COUNTY INCLUDING PORTOLA,
SUSANVILLE AND GERLACH. WE KEPT AN AREA OF SCATTERED SHOWERS IN
THESE AREAS THROUGH THIS MORNING. WHILE THE LAST LIGHTNING STRIKE
OVER THE REGION WAS REPORTED AROUND 1 AM, A FEW EMBEDDED
THUNDERSTORMS COULD STILL OCCUR THIS MORNING.
THIS AFTERNOON APPEARS TO BE QUITE ACTIVE AGAIN AS CONVECTION IS
PROJECTED TO BEGIN FORMING BETWEEN NOON AND 1 PM IN AREAS AWAY
FROM THE SHOWER BAND. WITH PLENTY OF MOISTURE IN PLACE,
INSTABILITY WILL INCREASE WITH SOME CAPE VALUES NEAR 1000 J/KG.
INCREASING WINDS ALOFT WILL LEAD TO INCREASED VERTICAL WIND SHEAR
WITH UPPER LEVEL JET APPROACHING THE SIERRA PROVIDING SOME LARGER
SCALE LIFT. THIS SHOULD LEAD TO FASTER CELL MOTION COMPARED TO
YESTERDAY AND PROBABLY A MORE LIMITED THREAT OF FLOODING. HOWEVER,
IF THE PROJECTED INSTABILITY IS REALIZED, MANY OF THE STORMS THAT
DEVELOP COULD BECOME STRONG WITH SOME SEVERE CELLS POSSIBLE.
DAMAGING WINDS WILL BE THE PRIMARY CONCERN, ALONG WITH AN
INCREASING HAIL THREAT. WHILE STRONG STORMS ARE POSSIBLE ANYWHERE
IN THE REGION THIS AFTERNOON AND EARLY EVENING, THE PROBABILITY IS
A LITTLE HIGHER FROM RENO-CARSON CITY EASTWARD INTO CHURCHILL AND
PERSHING COUNTIES.
FOR TONIGHT, WITH THE UPPER JET REMAINING OVERHEAD AND BEST
DIVERGENCE ALOFT SETTING UP OVER NORTHWEST NV AND NORTHEAST CA,
SOME SHOWERS AND STORMS COULD CONTINUE IN THESE AREAS OVERNIGHT
INTO TUESDAY MORNING.
ON TUESDAY, UPPER LOW OFF THE NORTHERN CA COAST IS PROJECTED TO
EJECT INLAND AND PRODUCE A MORE LOCALIZED AREA OF FORCING MAINLY
NORTH OF SUSANVILLE AND GERLACH WHERE THE BEST CHANCE OF
CONVECTION IS INDICATED. OTHERWISE, A FEW CELLS COULD DEVELOP
MAINLY EAST OF RENO-CARSON CITY WHERE INCREASING WEST WINDS PRODUCE
A CONVERGENCE ZONE BY LATE AFTERNOON. INSTABILITY IS STILL DECENT
SO SOME STRONG CELLS ARE STILL POSSIBLE WITH FASTER MOTIONS
INCREASING THE THREAT OF LIGHTNING-INDUCED FIRE STARTS,
ESPECIALLY IN AREAS THAT DID NOT RECEIVE SIGNIFICANT RAINFALL IN
THE PAST WEEK. HOWEVER, WINDS ALOFT MAY BECOME TOO STRONG AND SHEAR
OFF THE TOPS OF SOME STORMS BEFORE THEY CAN DEVELOP TO THEIR FULL
POTENTIAL.
BEHIND THE SHORTWAVE PASSAGE, DRIER AND MORE STABLE AIR MASS WILL
QUICKLY SPREAD OVER THE REGION, RESULTING IN A QUICKER END TO
THUNDERSTORMS TUESDAY EVENING AND NO STORMS DEVELOPING ON
WEDNESDAY. THE MAIN CONCERN ON WEDNESDAY WILL BE LOWERING HUMIDITY
AND WIND GUSTS NEAR OR SLIGHTLY ABOVE 30 MPH, ESPECIALLY FROM I-80
NORTHWARD WHICH COULD SUPPORT A QUICKER SPREAD OF ANY EXISTING
FIRES. MJD
LONG TERM...THURSDAY THROUGH SUNDAY...
MADE VERY MINIMAL CHANGES TO THE INHERITED EXTENDED FORECAST THIS
MORNING AS MODELS REMAIN IN GOOD AGREEMENT THROUGH MOST OF THE
PERIOD.
UPPER LOW NORTH OF THE FORECAST AREA PULLS AWAY THURSDAY WITH
DECREASING WINDS OVER THE REGION. A FLAT RIDGE DEVELOPS BY FRIDAY
WITH A SLIGHT INCREASE IN TEMPS. THE UPPER RIDGE BEGINS TO BUILD
BACK INTO THE REGION FROM THE SOUTHEAST IN EARNEST BY SATURDAY WITH
HIGH TEMPS CLIMBING BACK ABOVE AVERAGE AND APPROACHING TRIPLE DIGITS
OVER THE WRN NV VALLEYS. TEMPS SHOULD BE EVEN WARMER FOR SUNDAY AS
THIS RIDGE INTENSIFIES.
THE ORIENTATION OF THE RIDGE STARTS TO BECOME MORE NW TO SE AND THIS
SHOULD ALLOW SOME MOISTURE RETURN TO THE SW PORTIONS OF THE CWA OVER
THE WEEKEND. WILL LEAVE THE SLIGHT CHANCE POPS OVER THE REGION
SUNDAY. AS OF THIS FORECAST THERE DOES NOT APPEAR TO BE ENOUGH MOISTURE
SATURDAY TO PRODUCE MORE THAN MODERATE CUMULUS BUILD UPS OVER THE
SRN CWA.
BEYOND THE EXTENDED TIME PERIOD THERE DOES APPEAR TO BE INCREASING
CHANCES FOR TSTMS BY MONDAY AND TUESDAY OF NEXT WEEK. 20
AVIATION...
SHOWERS AND ISOLATED TSTMS WILL BE IN PLACE THIS MORNING OVER THE
WRN PORTIONS OF NV AND INTO THE NORTHERN SIERRA AS AN UPPER LEVEL
AREA OF LOW PRESSURE HANGS OVER THE REGION. WHILE CIGS SHOULD BE VFR
OR BETTER THIS MORNING IN MOST LOCATIONS...THERE WILL LIKELY BE SOME
MOUNTAIN OBSCURATIONS EARLY TODAY.
MORE TSTMS ARE EXPECTED THIS AFTERNOON WITH THE BEST COVERAGE NORTH
OF HIGHWAY 50. ONCE AGAIN THE PRIMARY THREAT WITH THESE STORMS FOR
AVIATION INTERESTS WILL BE HAIL...GUSTY SFC WINDS AND FLIGHT LEVEL
TURBULENCE WITH LOW LEVEL WIND SHEAR. WINDS GUSTS OF 50 KTS ARE
POSSIBLE IN THE STRONGEST TSTMS TODAY.
THERE REMAINS A SMALL CHANCE OF TSTMS NORTH OF HIGHWAY 50 AGAIN
TUESDAY...BUT THE CHANCES ARE LESS THAN TODAY. DRIER AIR PUSHES INTO
THE REGION BY WEDNESDAY WITH SLIGHTLY STRONGER SFC WINDS
OVERALL...BUT NO CHANCE OF STORMS. 20
&&
.REV WATCHES/WARNINGS/ADVISORIES...
NV...NONE.
CA...NONE.
&&
$$
FOR MORE INFORMATION FROM THE NATIONAL WEATHER SERVICE VISIT...
HTTP://WEATHER.GOV/RENO (ALL LOWER CASE)
AREA FORECAST DISCUSSION
NWS RENO NV
535 AM PDT MON JUL 21 2014
.UPDATE...
CLOUD TOPS CONTINUE TO COOL OVER WRN NV AND A SMALL PART OF NE CA.
THIS IS INDICATIVE OF INCREASING LIFT AS THE DEFORMATION AXIS OVER
THE AREA REMAINS IN PLACE AND APPEARS TO BE STRENGTHENING A BIT.
WE HAVE SEEN A FEW LIGHTNING STRIKES OVER THE LAST HOUR NORTH OF
GERLACH AND WITH COOLING CLOUD TOPS IT IS VERY POSSIBLE THAT A FEW
MORE STRIKES WILL DEVELOP. RADAR IMAGERY SHOWS THE AREA OF HIGHEST
RETURNS HAS NARROWED A BIT...BUT IT IS UNDER THE AREA OF COOLING
CLOUD TOPS. WILL BUMP UP POPS FROM NW PERSHING COUNTY INTO SIERRA
AND NEVADA COUNTIES IN ERN CA EARLY THIS MORNING. WITH A FAIRLY
CLEAR SKY OVER THE SRN 1/3 OF THE FORECAST AREA...THE THINKING IS
THAT CONVECTIVE DEVELOPMENT MAY BEGIN NEAR THE INTERFACE OF THE
CLOUD COVER TO THE NORTH AND CLEARING TO THE SOUTH BY LATE MORNING
OR EARLY AFTERNOON. HAVE EXPANDED SCATTERED COVERAGE A BIT
FARTHER SOUTH TO ACCOUNT FOR THAT POSSIBILITY THIS AFTERNOON. 20
&&
.PREVIOUS DISCUSSION... /ISSUED 338 AM PDT MON JUL 21 2014/
SYNOPSIS...
SCATTERED SHOWERS AND THUNDERSTORMS WILL REDEVELOP TODAY AS A MOIST
AND UNSTABLE AIR MASS REMAINS IN PLACE. STRONG STORMS WILL BE
POSSIBLE THIS AFTERNOON AND EVENING. ISOLATED THUNDERSTORMS ARE
POSSIBLE AGAIN TUESDAY AS LOW PRESSURE LIFTS NORTH ACROSS
CALIFORNIA. DRIER AND LOCALLY BREEZY CONDITIONS ARE EXPECTED BY
MID WEEK, FOLLOWED BY A WARMING TREND BY NEXT WEEKEND.
SHORT TERM...
RAIN SHOWERS CONTINUE ACROSS GENERALLY FROM INTERSTATE 80
NORTHWARD INTO NORTHEAST CA-NORTHWEST NV. THIS ACTIVITY MAY
PERSIST THROUGH THIS MORNING WITH SHORT RANGE HRRR MODEL GUIDANCE
INDICATING THE MAIN BAND OF SHOWERS DRIFTING SLOWLY NORTHWARD INTO
PLUMAS, LASSEN AND NORTHERN WASHOE COUNTY INCLUDING PORTOLA,
SUSANVILLE AND GERLACH. WE KEPT AN AREA OF SCATTERED SHOWERS IN
THESE AREAS THROUGH THIS MORNING. WHILE THE LAST LIGHTNING STRIKE
OVER THE REGION WAS REPORTED AROUND 1 AM, A FEW EMBEDDED
THUNDERSTORMS COULD STILL OCCUR THIS MORNING.
THIS AFTERNOON APPEARS TO BE QUITE ACTIVE AGAIN AS CONVECTION IS
PROJECTED TO BEGIN FORMING BETWEEN NOON AND 1 PM IN AREAS AWAY
FROM THE SHOWER BAND. WITH PLENTY OF MOISTURE IN PLACE,
INSTABILITY WILL INCREASE WITH SOME CAPE VALUES NEAR 1000 J/KG.
INCREASING WINDS ALOFT WILL LEAD TO INCREASED VERTICAL WIND SHEAR
WITH UPPER LEVEL JET APPROACHING THE SIERRA PROVIDING SOME LARGER
SCALE LIFT. THIS SHOULD LEAD TO FASTER CELL MOTION COMPARED TO
YESTERDAY AND PROBABLY A MORE LIMITED THREAT OF FLOODING. HOWEVER,
IF THE PROJECTED INSTABILITY IS REALIZED, MANY OF THE STORMS THAT
DEVELOP COULD BECOME STRONG WITH SOME SEVERE CELLS POSSIBLE.
DAMAGING WINDS WILL BE THE PRIMARY CONCERN, ALONG WITH AN
INCREASING HAIL THREAT. WHILE STRONG STORMS ARE POSSIBLE ANYWHERE
IN THE REGION THIS AFTERNOON AND EARLY EVENING, THE PROBABILITY IS
A LITTLE HIGHER FROM RENO-CARSON CITY EASTWARD INTO CHURCHILL AND
PERSHING COUNTIES.
FOR TONIGHT, WITH THE UPPER JET REMAINING OVERHEAD AND BEST
DIVERGENCE ALOFT SETTING UP OVER NORTHWEST NV AND NORTHEAST CA,
SOME SHOWERS AND STORMS COULD CONTINUE IN THESE AREAS OVERNIGHT
INTO TUESDAY MORNING.
ON TUESDAY, UPPER LOW OFF THE NORTHERN CA COAST IS PROJECTED TO
EJECT INLAND AND PRODUCE A MORE LOCALIZED AREA OF FORCING MAINLY
NORTH OF SUSANVILLE AND GERLACH WHERE THE BEST CHANCE OF
CONVECTION IS INDICATED. OTHERWISE, A FEW CELLS COULD DEVELOP
MAINLY EAST OF RENO-CARSON CITY WHERE INCREASING WEST WINDS PRODUCE
A CONVERGENCE ZONE BY LATE AFTERNOON. INSTABILITY IS STILL DECENT
SO SOME STRONG CELLS ARE STILL POSSIBLE WITH FASTER MOTIONS
INCREASING THE THREAT OF LIGHTNING-INDUCED FIRE STARTS,
ESPECIALLY IN AREAS THAT DID NOT RECEIVE SIGNIFICANT RAINFALL IN
THE PAST WEEK. HOWEVER, WINDS ALOFT MAY BECOME TOO STRONG AND SHEAR
OFF THE TOPS OF SOME STORMS BEFORE THEY CAN DEVELOP TO THEIR FULL
POTENTIAL.
BEHIND THE SHORTWAVE PASSAGE, DRIER AND MORE STABLE AIR MASS WILL
QUICKLY SPREAD OVER THE REGION, RESULTING IN A QUICKER END TO
THUNDERSTORMS TUESDAY EVENING AND NO STORMS DEVELOPING ON
WEDNESDAY. THE MAIN CONCERN ON WEDNESDAY WILL BE LOWERING HUMIDITY
AND WIND GUSTS NEAR OR SLIGHTLY ABOVE 30 MPH, ESPECIALLY FROM I-80
NORTHWARD WHICH COULD SUPPORT A QUICKER SPREAD OF ANY EXISTING
FIRES. MJD
LONG TERM...THURSDAY THROUGH SUNDAY...
MADE VERY MINIMAL CHANGES TO THE INHERITED EXTENDED FORECAST THIS
MORNING AS MODELS REMAIN IN GOOD AGREEMENT THROUGH MOST OF THE
PERIOD.
UPPER LOW NORTH OF THE FORECAST AREA PULLS AWAY THURSDAY WITH
DECREASING WINDS OVER THE REGION. A FLAT RIDGE DEVELOPS BY FRIDAY
WITH A SLIGHT INCREASE IN TEMPS. THE UPPER RIDGE BEGINS TO BUILD
BACK INTO THE REGION FROM THE SOUTHEAST IN EARNEST BY SATURDAY WITH
HIGH TEMPS CLIMBING BACK ABOVE AVERAGE AND APPROACHING TRIPLE DIGITS
OVER THE WRN NV VALLEYS. TEMPS SHOULD BE EVEN WARMER FOR SUNDAY AS
THIS RIDGE INTENSIFIES.
THE ORIENTATION OF THE RIDGE STARTS TO BECOME MORE NW TO SE AND THIS
SHOULD ALLOW SOME MOISTURE RETURN TO THE SW PORTIONS OF THE CWA OVER
THE WEEKEND. WILL LEAVE THE SLIGHT CHANCE POPS OVER THE REGION
SUNDAY. AS OF THIS FORECAST THERE DOES NOT APPEAR TO BE ENOUGH MOISTURE
SATURDAY TO PRODUCE MORE THAN MODERATE CUMULUS BUILD UPS OVER THE
SRN CWA.
BEYOND THE EXTENDED TIME PERIOD THERE DOES APPEAR TO BE INCREASING
CHANCES FOR TSTMS BY MONDAY AND TUESDAY OF NEXT WEEK. 20
AVIATION...
SHOWERS AND ISOLATED TSTMS WILL BE IN PLACE THIS MORNING OVER THE
WRN PORTIONS OF NV AND INTO THE NORTHERN SIERRA AS AN UPPER LEVEL
AREA OF LOW PRESSURE HANGS OVER THE REGION. WHILE CIGS SHOULD BE VFR
OR BETTER THIS MORNING IN MOST LOCATIONS...THERE WILL LIKELY BE SOME
MOUNTAIN OBSCURATIONS EARLY TODAY.
MORE TSTMS ARE EXPECTED THIS AFTERNOON WITH THE BEST COVERAGE NORTH
OF HIGHWAY 50. ONCE AGAIN THE PRIMARY THREAT WITH THESE STORMS FOR
AVIATION INTERESTS WILL BE HAIL...GUSTY SFC WINDS AND FLIGHT LEVEL
TURBULENCE WITH LOW LEVEL WIND SHEAR. WINDS GUSTS OF 50 KTS ARE
POSSIBLE IN THE STRONGEST TSTMS TODAY.
THERE REMAINS A SMALL CHANCE OF TSTMS NORTH OF HIGHWAY 50 AGAIN
TUESDAY...BUT THE CHANCES ARE LESS THAN TODAY. DRIER AIR PUSHES INTO
THE REGION BY WEDNESDAY WITH SLIGHTLY STRONGER SFC WINDS
OVERALL...BUT NO CHANCE OF STORMS. 20
&&
.REV WATCHES/WARNINGS/ADVISORIES...
NV...NONE.
CA...NONE.
&&
$$
FOR MORE INFORMATION FROM THE NATIONAL WEATHER SERVICE VISIT...
HTTP://WEATHER.GOV/RENO (ALL LOWER CASE)
AREA FORECAST DISCUSSION
NWS RENO NV
338 AM PDT MON JUL 21 2014
.SYNOPSIS...
SCATTERED SHOWERS AND THUNDERSTORMS WILL REDEVELOP TODAY AS A MOIST
AND UNSTABLE AIR MASS REMAINS IN PLACE. STRONG STORMS WILL BE
POSSIBLE THIS AFTERNOON AND EVENING. ISOLATED THUNDERSTORMS ARE
POSSIBLE AGAIN TUESDAY AS LOW PRESSURE LIFTS NORTH ACROSS
CALIFORNIA. DRIER AND LOCALLY BREEZY CONDITIONS ARE EXPECTED BY
MID WEEK, FOLLOWED BY A WARMING TREND BY NEXT WEEKEND.
&&
.SHORT TERM...
RAIN SHOWERS CONTINUE ACROSS GENERALLY FROM INTERSTATE 80
NORTHWARD INTO NORTHEAST CA-NORTHWEST NV. THIS ACTIVITY MAY
PERSIST THROUGH THIS MORNING WITH SHORT RANGE HRRR MODEL GUIDANCE
INDICATING THE MAIN BAND OF SHOWERS DRIFTING SLOWLY NORTHWARD INTO
PLUMAS, LASSEN AND NORTHERN WASHOE COUNTY INCLUDING PORTOLA,
SUSANVILLE AND GERLACH. WE KEPT AN AREA OF SCATTERED SHOWERS IN
THESE AREAS THROUGH THIS MORNING. WHILE THE LAST LIGHTNING STRIKE
OVER THE REGION WAS REPORTED AROUND 1 AM, A FEW EMBEDDED
THUNDERSTORMS COULD STILL OCCUR THIS MORNING.
THIS AFTERNOON APPEARS TO BE QUITE ACTIVE AGAIN AS CONVECTION IS
PROJECTED TO BEGIN FORMING BETWEEN NOON AND 1 PM IN AREAS AWAY
FROM THE SHOWER BAND. WITH PLENTY OF MOISTURE IN PLACE,
INSTABILITY WILL INCREASE WITH SOME CAPE VALUES NEAR 1000 J/KG.
INCREASING WINDS ALOFT WILL LEAD TO INCREASED VERTICAL WIND SHEAR
WITH UPPER LEVEL JET APPROACHING THE SIERRA PROVIDING SOME LARGER
SCALE LIFT. THIS SHOULD LEAD TO FASTER CELL MOTION COMPARED TO
YESTERDAY AND PROBABLY A MORE LIMITED THREAT OF FLOODING. HOWEVER,
IF THE PROJECTED INSTABILITY IS REALIZED, MANY OF THE STORMS THAT
DEVELOP COULD BECOME STRONG WITH SOME SEVERE CELLS POSSIBLE.
DAMAGING WINDS WILL BE THE PRIMARY CONCERN, ALONG WITH AN
INCREASING HAIL THREAT. WHILE STRONG STORMS ARE POSSIBLE ANYWHERE
IN THE REGION THIS AFTERNOON AND EARLY EVENING, THE PROBABILITY IS
A LITTLE HIGHER FROM RENO-CARSON CITY EASTWARD INTO CHURCHILL AND
PERSHING COUNTIES.
FOR TONIGHT, WITH THE UPPER JET REMAINING OVERHEAD AND BEST
DIVERGENCE ALOFT SETTING UP OVER NORTHWEST NV AND NORTHEAST CA,
SOME SHOWERS AND STORMS COULD CONTINUE IN THESE AREAS OVERNIGHT
INTO TUESDAY MORNING.
ON TUESDAY, UPPER LOW OFF THE NORTHERN CA COAST IS PROJECTED TO
EJECT INLAND AND PRODUCE A MORE LOCALIZED AREA OF FORCING MAINLY
NORTH OF SUSANVILLE AND GERLACH WHERE THE BEST CHANCE OF
CONVECTION IS INDICATED. OTHERWISE, A FEW CELLS COULD DEVELOP
MAINLY EAST OF RENO-CARSON CITY WHERE INCREASING WEST WINDS PRODUCE
A CONVERGENCE ZONE BY LATE AFTERNOON. INSTABILITY IS STILL DECENT
SO SOME STRONG CELLS ARE STILL POSSIBLE WITH FASTER MOTIONS
INCREASING THE THREAT OF LIGHTNING-INDUCED FIRE STARTS,
ESPECIALLY IN AREAS THAT DID NOT RECEIVE SIGNIFICANT RAINFALL IN
THE PAST WEEK. HOWEVER, WINDS ALOFT MAY BECOME TOO STRONG AND SHEAR
OFF THE TOPS OF SOME STORMS BEFORE THEY CAN DEVELOP TO THEIR FULL
POTENTIAL.
BEHIND THE SHORTWAVE PASSAGE, DRIER AND MORE STABLE AIR MASS WILL
QUICKLY SPREAD OVER THE REGION, RESULTING IN A QUICKER END TO
THUNDERSTORMS TUESDAY EVENING AND NO STORMS DEVELOPING ON
WEDNESDAY. THE MAIN CONCERN ON WEDNESDAY WILL BE LOWERING HUMIDITY
AND WIND GUSTS NEAR OR SLIGHTLY ABOVE 30 MPH, ESPECIALLY FROM I-80
NORTHWARD WHICH COULD SUPPORT A QUICKER SPREAD OF ANY EXISTING
FIRES. MJD
.LONG TERM...THURSDAY THROUGH SUNDAY...
MADE VERY MINIMAL CHANGES TO THE INHERITED EXTENDED FORECAST THIS
MORNING AS MODELS REMAIN IN GOOD AGREEMENT THROUGH MOST OF THE
PERIOD.
UPPER LOW NORTH OF THE FORECAST AREA PULLS AWAY THURSDAY WITH
DECREASING WINDS OVER THE REGION. A FLAT RIDGE DEVELOPS BY FRIDAY
WITH A SLIGHT INCREASE IN TEMPS. THE UPPER RIDGE BEGINS TO BUILD
BACK INTO THE REGION FROM THE SOUTHEAST IN EARNEST BY SATURDAY WITH
HIGH TEMPS CLIMBING BACK ABOVE AVERAGE AND APPROACHING TRIPLE DIGITS
OVER THE WRN NV VALLEYS. TEMPS SHOULD BE EVEN WARMER FOR SUNDAY AS
THIS RIDGE INTENSIFIES.
THE ORIENTATION OF THE RIDGE STARTS TO BECOME MORE NW TO SE AND THIS
SHOULD ALLOW SOME MOISTURE RETURN TO THE SW PORTIONS OF THE CWA OVER
THE WEEKEND. WILL LEAVE THE SLIGHT CHANCE POPS OVER THE REGION
SUNDAY. AS OF THIS FORECAST THERE DOES NOT APPEAR TO BE ENOUGH MOISTURE
SATURDAY TO PRODUCE MORE THAN MODERATE CUMULUS BUILD UPS OVER THE
SRN CWA.
BEYOND THE EXTENDED TIME PERIOD THERE DOES APPEAR TO BE INCREASING
CHANCES FOR TSTMS BY MONDAY AND TUESDAY OF NEXT WEEK. 20
&&
.AVIATION...
SHOWERS AND ISOLATED TSTMS WILL BE IN PLACE THIS MORNING OVER THE
WRN PORTIONS OF NV AND INTO THE NORTHERN SIERRA AS AN UPPER LEVEL
AREA OF LOW PRESSURE HANGS OVER THE REGION. WHILE CIGS SHOULD BE VFR
OR BETTER THIS MORNING IN MOST LOCATIONS...THERE WILL LIKELY BE SOME
MOUNTAIN OBSCURATIONS EARLY TODAY.
MORE TSTMS ARE EXPECTED THIS AFTERNOON WITH THE BEST COVERAGE NORTH
OF HIGHWAY 50. ONCE AGAIN THE PRIMARY THREAT WITH THESE STORMS FOR
AVIATION INTERESTS WILL BE HAIL...GUSTY SFC WINDS AND FLIGHT LEVEL
TURBULENCE WITH LOW LEVEL WIND SHEAR. WINDS GUSTS OF 50 KTS ARE
POSSIBLE IN THE STRONGEST TSTMS TODAY.
THERE REMAINS A SMALL CHANCE OF TSTMS NORTH OF HIGHWAY 50 AGAIN
TUESDAY...BUT THE CHANCES ARE LESS THAN TODAY. DRIER AIR PUSHES INTO
THE REGION BY WEDNESDAY WITH SLIGHTLY STRONGER SFC WINDS
OVERALL...BUT NO CHANCE OF STORMS. 20
&&
.REV WATCHES/WARNINGS/ADVISORIES...
NV...NONE.
CA...NONE.
&&
$$
FOR MORE INFORMATION FROM THE NATIONAL WEATHER SERVICE VISIT...
HTTP://WEATHER.GOV/RENO (ALL LOWER CASE)
AREA FORECAST DISCUSSION
NWS DENVER/BOULDER CO
946 PM MDT TUE JUL 22 2014
.UPDATE...
ISSUED AT 946 PM MDT TUE JUL 22 2014
A FEW MINOR CHANGES COMING. STORMS IN PARK COUNTY HAVE BEEN
SLOSHING AROUND THE VALLEY...THEY HAVE ALMOST USED UP THE
AVAILABLE ENERGY AND WILL EITHER BE DISSIPATING OR MOVING
SOUTHEAST OUT OF THE COUNTY SOON.
EAST WINDS INTO NE COLORADO ARE A BIT STRONGER THAN EXPECTED AND
ARE BRINGING IN WARM MOIST AIR THAT IS WEAKLY CAPPED. WATCHING
A SERIOUS STORM AROUND CHADRON NEBRASKA DROPPING SOUTH THROUGH A
FAVORABLE AIRMASS...THOUGH THERE IS A BIT DRIER AIR AHEAD OF IT.
SOME CHANCE THIS COULD CLIP THE NE CORNER OF COLORADO AFTER
MIDNIGHT. MORE LIKELY OUTFLOW FROM THIS STORM...OR LOW LEVEL
CONVERGENCE IN THE EXISTING MOISTURE PLUME...COULD TRIGGER NEW
STORMS IN OUR AREA. CURRENT FORECAST ALREADY HAS SOME LOW POPS FOR
THIS IDEA...I WILL BUMP THEM UP SOME. GIVEN THE AMOUNT OF MOISTURE
VERSUS SHEAR I WOULD EXPECT STRONG PULSES ON BOUNDARIES TO BE THE
DOMINANT MODE...BUT THERE COULD BE SOME THREAT OF SEVERE HAIL AND
HEAVY RAIN. FOR THE DENVER AREA THE FORECAST IS LOOKING
GOOD...COULD HAVE SOME STRATUS IF WE GOT OUTFLOW FROM NEARBY
STORMS...BUT NOT LOOKING LIKELY AT THIS POINT.
&&
.SHORT TERM...(THIS EVENING THROUGH WEDNESDAY)
ISSUED AT 338 PM MDT TUE JUL 22 2014
TOWERING CUMULUS HAS BEEN CONFINED TO THE FRONT RANGE MOUNTAINS
AND FOOTHILLS...AND PARK COUNTY SO FAR...WITH ANY PRECIPITATION
JUST SOUTH OF THE FORECAST AREA TOWARD THE PIKES PEAK REGION.
STILL EXPECT ISOLATED SHOWERS/STORMS TO DEVELOP IN THE FRONT RANGE
MOUNTAINS AND FOOTHILLS LATE THIS AFTERNOON. IN THE LOWER
ELEVATIONS...THE CAP IS WEAKENING AS WE HAVE HAD FULL SUNSHINE
THROUGH THE DAY. LATEST ACARS SOUNDINGS SHOW IF WE REACH 95 NEAR
DENVER WE COULD BREAK THE CAP. AT THIS TIME...IT WOULD STILL BE
MORE LIKELY FOR THIS TO OCCUR ALONG THE ELEVATED TERRAIN OF THE
PALMER DIVIDE OR CHEYENNE RIDGE. THE LATEST HRRR AND RAP13 HINT
AT THIS...SO WILL CONTINUE THE LOW POPS IN/NEAR THOSE AREAS. ONLY
CHANGE TO WEATHER WAS TO ADD SOME LOW POPS OVER THE NORTHEAST
PLAINS LATE THIS EVENING AND OVERNIGHT AS LOW LEVEL JET AND
MOISTURE CONVERGENCE INCREASE. HOWEVER...THIS OCCURS UNDER A LARGE
DOMINATING RIDGE SO ONLY A SLIGHT CHANCE OF BREAKING THROUGH THE
CAP AT THIS POINT.
AREAS OF STRATUS MAY DEVELOP OVER THE EASTERN PLAINS AS WELL WITH
CONTINUED ADVECTION OF LOW LEVEL MOISTURE IN UPSLOPE
EAST/SOUTHEAST FLOW.
ON WEDNESDAY...LOW LEVEL FLOW TURNS FROM SOUTHEAST TO MORE
SOUTHERLY AS LEE TROUGH STRENGTHENS. LOOKS LIKE DENVER CONVERGENCE
ZONE WILL GET ERODED AS LEE TROUGH DEVELOPS AND STRONGER MIXING
OCCURS. AS A RESULT...BEST MOISTURE WILL LIKELY SHIFT NORTHWARD TO
NEAR THE WYOMING BORDER AREA BY AFTERNOON. CAPES THERE MAY REACH
1000-1500 J/KG WITH A STRONGER STORM POSSIBLE. ELSEWHERE...LOOKS
LIKE CONVECTION WILL BE HIGHER BASED WITH STRONG GUSTY OUTFLOW
WINDS AND BRIEF MODERATE RAIN. STORM COVERAGE WILL BE HIGHEST IN
MOUNTAINS WHERE A MID LEVEL MOISTURE PLUME IS EXPECTED TO ARRIVE
BY MID/LATE AFTERNOON.
.LONG TERM...(WEDNESDAY NIGHT THROUGH TUESDAY)
ISSUED AT 338 PM MDT TUE JUL 22 2014
SOME THUNDERSTORMS WILL CONTINUE WEDNESDAY EVENING...MAINLY ACROSS
THE MOUNTAINS. MAIN THREAT TO BE GUSTY OUTFLOW WINDS AS LOW LEVEL
MOISTURE WILL BE LIMITED. STORMS SHOULD END AROUND MIDNIGHT AS
AIRMASS STABILIZES. ON THURSDAY...UPPER RIDGE WILL BE OVER THE
AREA WITH THE CENTER OF HIGH OVER CENTRAL NEW MEXICO. RIDGE GETS
FLATTENED A BIT AS MID LEVEL SHORTWAVE MOVES ACROSS NORTHERN
COLORADO WITH FLOW ALOFT BECOMING A BIT MORE WESTERLY. THERE IS
SOME INCREASE IN MONSOON TYPE MOISTURE INTO COLORADO...MAINLY
ACROSS THE MOUNTAINS. THIS WILL PROVIDE FOR A CHANCE OF AFTERNOON
AND EVENING THUNDERSTORMS...WITH THE BEST CHANCE OVER THE
MOUNTAINS. STORMS TO PRODUCE GUSTY WINDS WITH BRIEF MODERATE RAIN.
FOR FRIDAY...UPPER RIDGE REMAINS OVER THE AREA WITH WESTERLY FLOW
ALOFT. MODELS INDICATE ANOTHER INFLUX OF MONSOONAL MOISTURE FLOW
INTO THE AREA...MAINLY ACROSS THE MOUNTAINS. DAYTIME HEATING TO
GENERATE SOME THUNDERSTORMS DURING THE AFTERNOON AND EVENING. A
WEAK SURFACE FRONT LOOKS TO MOVE ACROSS THE NORTHEAST PLAINS WITH
SOME SLIGHT LOW LEVEL COOLING. THIS MAY LIMIT THE THUNDERSTORM
CHANCES ACROSS THE PLAINS AND WILL KEEP THE BEST CHANCE FOR
THUNDERSTORMS OVER THE MOUNTAINS. HIGHS TO BE A FEW DEGREES COOLER
ACROSS NORTHEAST COLORADO...BUT SHOULD STILL BE IN THE LOWER AND
MIDDLE 90S. ON SATURDAY...MODELS SHOW THE UPPER RIDGE RETROGRADING
A BIT WITH THE FLOW ALOFT OVER COLORADO BECOMING WEST NORTHWEST.
MODELS SHOW SOME DECREASE IN THE MONSOON MOISTURE WITH MOST OF THE
MOISTURE BEING DISPLACED OVER SOUTHERN COLORADO. GFS STILL DRIER
THAT THE ECMWF...ESPECIALLY AT LOW LEVELS. WILL CONTINUE WITH A
SLIGHT CHANCE OF AFTERNOON AND EVENING THUNDERSTORMS. THERE
APPEARS TO BE A MID LEVEL SHORTWAVE WHICH MOVES ACROSS ACROSS
NORTHEAST COLORADO DURING THE AFTERNOON...PUSHING ANOTHER WEAK
FRONT INTO THE AREA. LIFT WITH THIS WAVE MAY HELP INCREASE THE
THUNDERSTORM CHANCES. FOR NOW WILL KEEP THE BEST CHANCE OVER THE
HIGH COUNTRY. HIGHS TO BE IN THE LOW AND MID 90S ACROSS THE
PLAINS.
FOR THE LATER DAYS...SUNDAY THROUGH TUESDAY. FLOW ALOFT TO BECOME
NORTHWEST SUNDAY. BOTH ECMWF AND GFS SHOW A SURFACE HIGH MOVING
INTO NORTHEAST PLAINS WITH LOW LEVEL FLOW BECOME SOUTHEAST. THIS
WILL HELP BRING SOME LOW LEVEL MOISTURE INTO THE AREA. FOR NOW
WILL KEEP THE BEST CHANCE OF THUNDERSTORMS OVER THE MOUNTAINS.
COOLER AIRMASS WITH HIGHS IN THE MID 80S ACROSS THE PLAINS.
NORTHWEST FLOW ALOFT CONTINUES MONDAY AND TUESDAY WITH HIGHS
SLIGHTLY BELOW AVERAGE ACROSS NORTHEAST COLORADO. ENOUGH MOISTURE
FOR A SLIGHT CHANCE OF AFTERNOON AND EVENING THUNDERSTORMS EACH
DAY...MAINLY OVER THE MOUNTAINS.
&&
.AVIATION...(FOR THE TAFS THROUGH 00Z WEDNESDAY LATE AFTERNOON)
ISSUED AT 946 PM MDT TUE JUL 22 2014
VFR EXPECTED THROUGH WEDNESDAY. LOW LEVEL MOISTURE WILL INCREASE
OVERNIGHT AND THERE IS A CHANCE OF SOME STRATUS BELOW 1000 FT AGL.
ALSO EXPECTING A DENVER CYCLONE TO DEVELOP TOWARD MORNING...FOR
NOW FORECASTING LIGHT WINDS AT KDEN/KAPA AROUND SUNRISE BUT THE
WINDS COULD BE NW FOR A WHILE. ON WEDNESDAY...SOUTHERLY WINDS
WILL DEVELOP AND INCREASE TO 12G20KTS BY 18Z-21Z. ONLY A SLIGHT 20
PERCENT CHANCE OF STORMS AFTER 21Z.
&&
.BOU WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...GIMMESTAD
SHORT TERM...BARJENBRUCH
LONG TERM...D-L
AVIATION...GIMMESTAD
AREA FORECAST DISCUSSION
NWS PUEBLO CO
328 PM MDT MON JUL 21 2014
.SHORT TERM...(THIS EVENING THROUGH TUESDAY)
ISSUED AT 328 PM MDT MON JUL 21 2014
REMNANT MONSOON MOISTURE PLUME EXTENDS ACROSS CENTRAL AND SOUTHEAST
COLORADO WITH WEAK SHORTWAVE ACROSS SOUTHEAST CO EXPECTED TO LIFT TO
THE NORTHEAST THIS AFTERNOON WITHIN THE UPPER HIGH. SO FAR...CLOUDS
HAVE BEEN HOLDING DOWN THE HEATING...WHICH HAS KEPT TEMPERATURES
FROM HITTING 100 ALONG THE I-25 CORRIDOR AND ADJACENT PLAINS.
FARTHER EAST A BIT MORE SUN WILL LIKELY ALLOW TEMPERATURES TO HIT
LOWER 100S OUT TOWARDS LAA. INSTABILITY STILL LOOKS BEST THIS
AFTERNOON TO THE EAST OF A LINE FROM EADS TO LAS ANIMAS TO KIM. IF
DEW POINTS CAN STAY IN THE LOWER 50S...THEN 1500 J/KG (OR A LITTLE
BETTER) OF CAPE WILL REMAIN IN PLACE ACROSS THE FAR SOUTHEAST
PLAINS. WEAK FLOW WITHIN THE UPPER RIDGE WILL KEEP DEEP LAYER
SHEARS ON THE WEAK SIDE FOR MOST OF THE AREA...WHICH SHOULD LIMIT
STORM ORGANIZATION. BUT WITH DOWNDRAFT CAPES OF 1500+ J/KG...GUSTY
OUT FLOW WINDS TO AROUND 60 MPH...AND HAIL NEAR 1 INCH IN DIAMETER
WILL BE POSSIBLE WITH STORMS IN THIS AREA. ELSEWHERE...GUSTY WINDS
AND LIGHTNING LOOK TO BE THE MAIN THREAT. ATMOSPHERE DOES NOT LOOK
VERY CONDUCIVE FOR FLASH FLOODING ON AREA BURN SCARS TODAY...BUT FOR
THE WALDO IT DOESN`T TAKE MUCH TO CAUSE PROBLEMS...SO THIS AREA WILL
BE MONITORED CLOSELY. LATEST HRRR SUGGESTS WALDO WILL BE MISSED
TODAY.
FRONT DROPS THROUGH THE PLAINS EARLY TUESDAY MORNING AND MONSOON
PLUME APPEARS TO GET SHUNTED OFF TO THE SOUTH...THOUGH AT LEAST SOME
RESIDUAL MOISTURE WILL REMAIN IN PLACE. MOISTURE RETURN BEHIND THE
FRONT LOOKS MEAGER...SO OVERALL...IT LOOKS LIKE ANOTHER DAY OF
MAINLY ISOLATED THUNDERSTORMS. IF DEW POINTS CAN INCREASE INTO THE
LOWER TO MID 50S AS NAM12 SUGGESTS...WE COULD SEE ANOTHER STRONG TO
MARGINALLY SEVERE THUNDERSTORM DAY ACROSS THE FAR SOUTHEAST PLAINS
AGAIN. HAVING A HARD TIME BUYING THE 100+ TEMPERATURES ADVERTISED
BY GUIDANCE FOR PUB. SOME LOWER 100S OUT ON THE FAR SOUTHEAST
PLAINS LOOK REASONABLE...BUT KEPT TEMPERATURES A TAD LOWER FOR PUB
AS GUIDANCE HAS BEEN RUNNING TOO HOT LATELY AND EASTERLY WINDS DON`T
USUALLY BODE FOR SUCH WARM TEMPERATURES. AS FOR FLASH FLOOD THREAT
ON THE BURN SCARS...THIS STILL LOOKS RATHER LOW AT THIS POINT. -KT
.LONG TERM...(TUESDAY NIGHT THROUGH MONDAY)
ISSUED AT 328 PM MDT MON JUL 21 2014
TUESDAY NIGHT-WEDNESDAY NIGHT...A BROAD...HOT (600DM) UPPER HIGH
CONTINUES TO BUILD ACROSS THE STATE WITH THE MAIN MONSOONAL MOISTURE
PLUME BEING SHUNTED INTO THE DESERT SW THROUGH THE GREAT BASIN AND
WESTERN COLORADO...AS FLOW ALOFT BECOMES MORE SOUTH TO SOUTHEAST
ACROSS THE AREA. CONVECTION TO BE ON THE WANE TUESDAY EVENING WITH
GFS LIKELY OVERDONE IN ITS QPF FIELD...THOUGH HAVE KEPT SOME
ISOLATED POPS ACROSS THE SW AND CENTRAL MTS THROUGH THE OVERNIGHT
HOURS. A WEAK BACKDOOR COLD FRONT MOVES ACROSS EASTERN COLORADO
EARLY WEDNESDAY MORNING WITH BREEZY EAST TO SOUTHEAST LOW LEVEL
UPSLOPE STRENGTHENING THROUGH THE AFTERNOON ACROSS THE PLAINS. WITH
ENOUGH MOISTURE UNDERNEATH THE HIGH...ALONG WITH A POSSIBLE WEAK
DISTURBANCE MOVING THROUGH THE SOUTHERLY FLOW ALOFT ACROSS THE
EASTERN GREAT BASIN...SHOULD SEE SCATTERED AFTERNOON AND EVENING
STORMS OVER AND NEAR THE HIGHER TERRAIN...WITH THE BEST COVERAGE
ACROSS THE SW AND CENTRAL MTS. LOCALLY HEAVY RAINFALL REMAINS
POSSIBLE...ESPECIALLY ACROSS WESTERN COLORADO...WITH MODEL SOUNDINGS
INDICATING CAP TO HOLD ACROSS THE PLAINS THROUGH THE AFTERNOON
THOUGH HAVE KEPT SLIGHT POPS IN PLACE INTO THE EVENING HOURS. WITH
MORE CONVECTIVE CLOUD COVER AND DEVELOPING UPSLOPE FLOW...HIGH
TEMPERATURES TO BE A TAD COOLER ON WEDNESDAY ACROSS THE AREA DESPITE
THE UPPER RIDGING IN PLACE.
THURSDAY-FRIDAY...UPPER HIGH PROGGED TO SLOWLY RETROGRADE SOUTH AND
WEST INTO THE FOUR CORNERS REGION WITH SOME RESIDUAL MOISTURE
REMAINING WITHIN THE DEVELOPING WESTERLY FLOW ALOFT ACROSS THE
STATE. SHOULD CONTINUE TO SEE SCATTERED DIURNAL CONVECTION ACROSS
THE HIGH TERRAIN ON THURSDAY WITH A FEW STORMS MOVING ACROSS THE
PLAINS THROUGH THE EVENING HOURS...WITH ANOTHER WEAK BACKDOOR FRONT
MOVING ACROSS THE AREA. MUCH OF THE SAME EXPECTED ON FRIDAY...WITH
SLIGHTLY BETTER COVERAGE ACROSS THE EASTERN PLAINS WITH LOW LEVEL
UPSLOPE FLOW. TEMPERATURES TO BE AT OR ABOVE NORMAL THROUGH THE
PERIOD.
SATURDAY-MONDAY...UPPER HIGH CONTINUES TO BUILD NORTH AND WEST
ACROSS THE GREAT BASIN WITH BROAD NORTHWEST DEVELOPING ACROSS THE
STATE AS AN UPPER TROUGH CARVES OUT ACROSS THE CENTRAL CONUS.
THIS PATTERN LOOKS TO DRY OUT THE UPPER LEVELS OF THE ATMOSPEHRE
WITH OCCASIONAL SHORT WAVES AND ASSOCIATED FRONTS MOVING ACROSS
THE NORTHERN AND CENTRAL HIGH PLAINS KEEPING AMPLE LOW LEVEL
MOISTURE IN PLACE ACROSS EASTERN COLORADO. WITH THAT SAID...SHOULD
CONTINUE TO SEE DAILY CHANCES OF SHOWERS AND THUNDERSTORMS...WITH
INCREASING CONCERNS FOR SEVERE WEATHER AND LOCALLY HEAVY RAINFALL
ACROSS EASTERN COLORADO.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON)
ISSUED AT 328 PM MDT MON JUL 21 2014
VFR CONDITIONS EXPECTED AT TAF SITES THROUGH THE NEXT 24
HOURS. AN ISOLATED HIGH BASED THUNDERSTORM WILL BE POSSIBLE AT KALS
AND KCOS LATE THIS AFTERNOON AND EVENING WITH THE MAIN THREAT BEING
ERRATIC GUSTY WINDS UP TO 40 KTS. A STRONG STORM OR TWO WILL BE
POSSIBLE ACROSS THE FAR SOUTHEAST PLAINS TO THE EAST OF KLHX WHERE
ERRATIC GUSTS TO 50 KTS AND HAIL NEARING 1 INCH IN DIAMETER WILL BE
POSSIBLE. THUNDERSTORMS WILL DIMINISH DURING THE EVENING HOURS. A
FRONT WILL DROP THROUGH THE SOUTHEAST PLAINS ON TUESDAY BRINGING A
NORTH WIND SHIFT AROUND 15 KTS AT KCOS AND KPUB BETWEEN 15Z AND 16Z.
ISOLATED THUNDERSTORMS WILL BE POSSIBLE ONCE AGAIN TUESDAY AFTERNOON
WITH MAIN THREATS CONTINUING TO BE ERRATIC WIND GUSTS TO 40 KTS.
HOWEVER A STRONG STORM OR TWO WILL BE POSSIBLE TO THE EAST OF KLHX
WHERE SOME HAIL AND WIND GUSTS OVER 50 KTS WILL BE POSSIBLE. -KT
&&
.PUB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...KT
LONG TERM...MW
AVIATION...KT
AREA FORECAST DISCUSSION
NWS MIAMI FL
937 PM EDT TUE JUL 22 2014
.UPDATE...
THE AFTERNOON SHOWER AND THUNDERSTORM ACTIVITY DIMINISHED EARLIER
WITH VERY QUIET CONDITIONS EXPECTED TO PERSIST INTO THE OVERNIGHT
HOURS. THE LATEST HRRR MODEL RUN REFLECTS THIS
TREND...HOWEVER...DOES INDICATE SOME ISLTD/SCT ACTIVITY DEVELOPING
OVER THE ADJACENT ATLANTIC WATERS BY DAYBREAK WEDNESDAY. OVERNIGHT
TEMPERATURES ARE PROJECTED TO DIP INTO THE MID TO UPPER 70S ACROSS
THE LOCAL AREA FOR THE LOWS. OUTSIDE OF A FEW MINOR
ADJUSTMENTS...THE PREVIOUS FORECAST PACKAGE REMAINS ON TRACK THIS
EVENING WITH NO MAJOR UPDATES ANTICIPATED.
85/AG
&&
.PREV DISCUSSION... /ISSUED 738 PM EDT TUE JUL 22 2014/
AVIATION...
MAINLY VFR CONDITIONS TO PREVAIL OVER THE NEXT 24 HOURS AT ALL
SITES OUTSIDE OF ANY THUNDERSTORMS. WINDS SHOULD BE MAINLY LIGHT
AND VARIABLE THROUGH THE NIGHT BEFORE SOUTHEASTERLY FLOW RETURNS
TOMORROW AFTERNOON. PLACED VCTS IN AT ALL SITES AFTER 15Z-16Z
TOMORROW ALTHOUGH BELIEVE MOST OF THE CONVECTION WILL REMAIN
ACROSS THE INTERIOR AND GULF COAST AS A GULF BREEZE SHOULD
DEVELOP.
PREV DISCUSSION... /ISSUED 230 PM EDT TUE JUL 22 2014/
DISCUSSION...
THE WEATHER PATTERN HAS NOT CHANGED MUCH FROM YESTERDAY. A LOW
PRESSURE CENTER IS SITTING OVER THE MOBILE ALABAMA AREA, AND AN
AREA OF HIGH PRESSURE IS SITUATED TO THE EAST. THIS HAS CONTINUED
THE SOUTHERLY FLOW OVER SOUTH FLORIDA, WHICH HAS MAINTAINED
ABUNDANT MOISTURE AND ENOUGH INSTABILITY TO BRING SHOWERS AND
THUNDERSTORMS TO THE AREA. THE CONVECTIVE ACTIVITY SHOULD DWINDLE
THROUGH THE EVENING HOURS, WITH THE LOSS OF DAYTIME HEATING.
MODELS ARE IN PRETTY GOOD AGREEMENT WITH THE LOW WEAKENING AND THE
HIGH STRENGTHENING SOMEWHAT AND BUILDING SLOWLY WESTWARD. THIS
WILL KEEP A GENERALLY SOUTHERLY FLOW OVER SOUTH FLORIDA. WHILE
TOMORROW WILL SEE ANOTHER ROUND OF WIDESPREAD ACTIVITY, THURSDAY
AND FRIDAY LOOK TO BE MORE TOWARDS THE INTERIOR, WITH SLIGHTLY
LOWER PROBABILITY EACH DAY, AS THE LOW SLOWLY WEAKENS AND THE HIGH
GRADUALLY BUILDS.
LONG TERM...
BERMUDA RIDGE AND RELATIVELY DRY ATLANTIC AIR WILL REGULATE
WEATHER THROUGH THE WEEKEND...RESULTING IN A BIT BELOW NORMAL RAIN
CHANCES...HIGHEST OVER INTERIOR DURING THE AFTERNOONS. MAXIMA WILL
BE NEAR AVERAGE FOR LATE JULY...MAINLY LOWER 90S...WITH MINIMA A
FEW DEGREES ABOVE NORMAL...RANGING FROM MID 70S TO AROUND 80F
ALONG THE ATLANTIC COAST.
MARINE...
HIGH PRESSURE WILL SLOWLY BUILD OVER THE ATLANTIC WATERS. WITH
THE CENTER OF THE HIGH TO THE EAST OF THE AREA, SOUTHERLY FLOW
WILL CONTINUE THROUGH THE REST OF THE WEEK. WITH THE FLOW BEING
RELATIVELY LIGHT, SEAS ARE NOT EXPECTED TO BUILD OVER THE NEXT
FEW DAYS. HOWEVER, THUNDERSTORMS MAY PRODUCE LOCALLY ROUGH
CONDITIONS.
&&
.PRELIMINARY POINT TEMPS/POPS...
WEST PALM BEACH 76 90 78 91 / 30 60 20 30
FORT LAUDERDALE 77 89 82 91 / 30 60 20 20
MIAMI 77 91 80 91 / 20 60 20 30
NAPLES 76 91 76 92 / 10 60 20 40
&&
.MFL WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
AM...NONE.
GM...NONE.
&&
$$
SHORT TERM...30/KOB
LONG TERM....13/SI
AREA FORECAST DISCUSSION
NWS INDIANAPOLIS IN
1051 PM EDT TUE JUL 22 2014
.UPDATE...
THE NEAR TERM SECTION HAS BEEN UPDATED BELOW.
&&
.SYNOPSIS...
ISSUED AT 226 PM EDT TUE JUL 22 2014
THE CURRENT UPPER RIDGE BRIDGING FROM THE WEST ACROSS THE GREAT
LAKES WILL RETROGRADE WESTWARD. A SERIES OF MINOR LOW PRESSURE
TROUGHS TOP THE REBUILDING WESTERN US RIDGE TO REDEVELOP THE
EASTERN TROUGH NEXT WEEK. THIS MEANS A RETURN TO COOLER AND LESS
HUMID WEATHER.
AN INITIAL FRONTAL BOUNDARY WILL SWEEP ACROSS CENTRAL INDIANA
WEDNESDAY FOLLOWED BY RESORT LIKE HIGH PRESSURE FOR THURSDAY AND
FRIDAY. THE SERIES OF LOW PRESSURE SYSTEMS TOPPING THE RIDGE WILL
PRODUCE PERIODS OF THUNDERSTORM FRIDAY NIGHT INTO MONDAY OR
TUESDAY BEFORE ANOTHER DRY-OUT AND COOL DOWN WITH LOWS IN THE 50S
AND HIGHS IN THE 70S BY MID-WEEK NEXT WEEK.
&&
.NEAR TERM /TONIGHT/...
ISSUED AT 1050 PM EDT TUE JUL 22 2014
BASED ON EVENING CONVECTIVE/RADAR TRENDS AND HRRR GUIDANCE...HAVE
PUSHED POPS BACK SEVERAL HOURS AND LOWERED THEM. STRONGEST
CONVECTION ONGOING ACROSS LAKE MICHIGAN AND NORTHERN ILLINOIS
WHERE DYNAMICS ARE STRONGER. THIS ACTIVITY MAY BE ABLE TO EXPAND
ENOUGH TO IMPACT NORTHWESTERN FORECAST AREA LATER TONIGHT...BUT
THIS IS FAR FROM CERTAIN. PREVIOUS DISCUSSION FOLLOWS.
ISSUED AT 226 PM EDT TUE JUL 22 2014
ISSUE OF CONCERN IS STORM POTENTIAL TONIGHT. CURRENT WARM CAP ALOFT
MAY HELP INHIBIT WHATEVER CONVECTION DEVELOPS THIS EVENING OUT WEST.
COMBINED WITH OVERNIGHT STORM ARRIVAL AND STABILIZING TEMPS AND
STRONGEST FORCING REMAINING IN THE GREAT LAKES...EXPECT
DIMINISHING LINE OF STORMS/SHOWERS TO MOVE TO NEAR I-70 BY DAYBREAK
WEDNESDAY. WITH DEWPOINTS LIKELY TO CLIMB TO THE LOWER 70S AHEAD
OF THE FRONT...MIN TEMPS SHOULD BE NEAR 70 EXCEPT WHERE ANY HEAVY
DOWNPOURS DROP MINS TO UPPER 60S. WIDESPREAD RAIN IS UNCERTAIN BUT
LOCAL HALF INCH DOWNPOURS CAN BE EXPECTED WITH THE STRONGER
STORMS. SOME POTENTIAL FOR GUSTINESS WITH THESE STRONGER STORMS
BUT THESE SHOULD STAY BELOW SEVERE LIMITS.
&&
.SHORT TERM /WEDNESDAY THROUGH FRIDAY/...
ISSUED AT 226 PM EDT TUE JUL 22 2014
WEDNESDAY...ISSUE IS HOW LONG RAIN THREAT LINGERS AND POTENTIAL
FOR SEVERE. MODELS DIFFER SLIGHTLY ON TIMING BUT CLOSE ENOUGH TO
BLEND FOR GOOD FORECAST.
INITIAL THRUST OF CONVECTION SHOULD SAG SLOWLY SOUTH DURING
MORNING HOURS AHEAD OF WIND SHIFT/FRONTAL BOUNDARY. LOCATIONS
NORTHWEST OF A TERRE HAUTE TO MUNCIE LINE WILL LIKELY HAVE
ALREADY SEEN RAIN THREAT ENDED. SOUTH OF THERE...MORNING HEATING
WILL RENEW STORM COVERAGE AND STRENGTH IN OUR SOUTHERN COUNTIES.
GREATEST GROWTH IN COVERAGE AND STRENGTH...SUGGESTED BY ALL MODELS
WILL OCCUR SOUTH AND EAST OF OUR FORECAST AREA. STILL ENOUGH
ENERGY TO BUILD THAT LOCALIZED STRONG WIND GUSTS COULD OCCUR IN
OUR SOUTHERN MOST AREAS.
WEDNESDAY NIGHT INTO FRIDAY...
NO ISSUES THIS FORECAST PERIOD. CANADIAN HIGH PRESSURE BUILDS IN
AND DROPS DEWPOINTS BACK TO LOWER 50S...MIN TEMPS BACK INTO THE
MID AND UPPER 50S...AND MAX TEMPS BACK TO THE UPPER 70S AND LOWER
80S. FRONTAL BOUNDARY THAT DROPPED TO THE OHIO RIVER BEGINS
GETTING PULLED BACK NORTH AS LOW PRESSURE TRACKS INTO THE PLAINS
BRINGING A RETURN TO SOUTHWEST FLOW FRIDAY BUT NO STORMS BEFORE
FRIDAY NIGHT.
&&
.LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/...
ISSUED AT 138 PM EDT TUE JUL 22 2014
THERE IS A HIGH CONFIDENCE FORECAST WITH LITTLE REASON TO CHANGE THE
REGIONAL INITIALIZATION.
UNUSUALLY LARGE STRONG WEATHER PATTERNS FOR THIS TIME OF YEAR ARE
GOING TO PERSIST INTO NEXT WEEK. SUCH WELL DEFINED SYSTEMS ARE
RELATIVELY EASY FOR THE MODELS TO FORECAST. GIVEN THEIR FORECASTS
ARE CLOSE THERE IS A GOOD CHANCE THEY WILL WORK OUT.
FORECAST CONFIDENCE IS A LITTLE LOWER FOR SUNDAY AND SUNDAY NIGHT
THAN AT OTHER TIMES. THE REASON IS A FRONT WILL BE CROSSING THE
AREA...AND EVEN MINOR DIFFERENCES IN TIMING COULD HAVE A BIG
EFFECT ON THE SENSIBLE WEATHER.
&&
.AVIATION /DISCUSSION FOR THE 23/00Z TAFS/...
ISSUED AT 712 PM EDT TUE JUL 22 2014
VFR THROUGH THE PERIOD. SOME SMALL CHANCE FOR MVFR CONDITIONS LATE
TONIGHT INTO EARLY TOMORROW MORNING AS FRONT PASSES AND POSSIBLE
SHOWERS/THUNDERSTORMS MOVE THROUGH...BUT AT THIS POINT IT IS TOO LOW
PROBABILITY AND UNCERTAIN FOR INCLUSION.
QUIET CONDITIONS THROUGH THE EARLY PART OF THE OVERNIGHT AS A COLD
FRONT APPROACHES FROM THE WEST. AS THIS FRONT PASSES THROUGH THE
AREA...THUNDERSTORMS MAY BE POSSIBLE AT LAF/HUF. EASTWARD PROGRESS
OF THESE STORMS IS MORE UNCERTAIN...AND WILL ONLY CARRY VCSH AT
IND/BMG VS. VCTS AT THE OTHER TWO SITES.
FRONT WILL MOVE THROUGH AND WINDS WILL SWING TO THE NORTHWEST/NORTH
IN ITS WAKE TOMORROW...WITH ONLY SCATTERED FAIR WEATHER CUMULUS AND
SOME HIGH CLOUDS.
&&
.IND WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
SYNOPSIS...TDUD
NEAR TERM...TDUD/NIELD
SHORT TERM...TDUD
LONG TERM...JK
AVIATION...NIELD
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AREA FORECAST DISCUSSION
NWS NORTHERN INDIANA
732 PM EDT TUE JUL 22 2014
.SYNOPSIS...
ISSUED AT 727 PM EDT TUE JUL 22 2014
A COLD FRONT WILL MOVE ACROSS THE REGION OVERNIGHT INTO WEDNESDAY
MORNING. SCATTERED SHOWERS AND THUNDERSTORMS ARE POSSIBLE ALONG THE
FRONT AS IT PASSES THROUGH THE AREA. COOLER AND DRIER AIR WILL
FILTER IN BEHIND THE FRONT FOR WEDNESDAY THROUGH THE END OF THE
WEEK. LOWS TONIGHT WILL BE IN THE MID 60S TO AROUND 70 DEGREES WITH
HIGHS ON WEDNESDAY IN THE 70S.
&&
.SHORT TERM...(THIS EVENING THROUGH WEDNESDAY)
ISSUED AT 306 PM EDT TUE JUL 22 2014
REGIONAL RADARS SHOWING ONGOING CONVECTION CONTINUES TO MOVE ACROSS
FAR NORTHERN GREAT LAKES/SOUTHERN CANADA WITH SURFACE LOW WHILE
EARLIER MCS DISSIPATING OVER THE MID MISSISSIPPI VALLEY WITH NEW
CELLS STARTING TO FORM OVER IOWA THIS AFTERNOON. WATER VAPOR IMAGERY
AND LATEST RUC ANALYSIS SHOWS SHORT WAVE TROF MOVING ACROSS LAKE
SUPERIOR WITH UPPER JET WELL TO THE NORTH OVER THE HUDSON BAY. THIS
DETACHMENT OF UPPER FORCING WILL BE PROBLEMATIC FOR CONVECTION
MAINTAINING ALONG THE COLD FRONT AS IT MOVES THROUGH OVERNIGHT. BEST
CHANCES APPEAR TO BE IN THE NW CWA AS DECENT MASS CONVERGENCE ALONG
COLD FRONT WILL COMBINE WITH MODEST ELEVATED INSTABILITY...CAPES
AROUND 1500J/KG...SO IF CONVECTION IN IOWA IS ABLE TO BECOME MORE
ORGANIZED IT MAY HAVE ENOUGH SUPPORT TO MAINTAIN CONVECTIVE
COMPLEX...HOWEVER FORMING RIGHT ALONG THICKNESS RIDGE WILL HAVE SOME
UNCERTAINTY IN ITS FORWARD PROPAGATION. FRONT EXPECTED TO PUSH
THROUGH MUCH OF THE CWA BY WEDNESDAY MORNING WITH JUST LINGERING
CHANCES IN THE FAR SE CWA...TRENDING TOWARD A DRY FORECAST FOR THE
ENTIRE AREA BY AFTERNOON. WARM AND MUGGY CONDITIONS EXPECTED TONIGHT
FOR THE SE HALF WITH LOWS AROUND 70 WHILE FRONTAL PASSAGE WILL ALLOW
TEMPS TO DROP INTO THE MID 60S NW. COOLER AND LESS HUMID FOR
WEDNESDAY WITH HIGHS 75-80.
&&
.LONG TERM...(WEDNESDAY NIGHT THROUGH TUESDAY)
ISSUED AT 306 PM EDT TUE JUL 22 2014
COMFORTABLE/FAIR WX WILL PREVAIL WEDNESDAY NIGHT THROUGH FRIDAY
MORNING AS STABLE CANADIAN HIGH PRESSURE DROPS THROUGH. MID-UPPER
LEVEL FLOW WILL BRIEFLY TRANSITION TO A FLATTER/SEMI-ZONAL WNW
REGIME BY LATE FRIDAY INTO SATURDAY...WHILE IN THE LOW LEVELS WINDS
VEER MORE SOUTHERLY ALLOWING AN ACTIVE WARM FRONT TO WORK ENE INTO
THE REGION. LEAD/WEAK SHORTWAVE IN ADVANCE OF PRIMARY SHORTWAVE
TROUGH AND INCREASING MASS/MOISTURE CONVERGENCE ALONG THE DEVELOPING
FRONT SUPPORT INHERITED CHANCE POPS FOR SHOWERS/STORMS DURING THIS
TIME...MAINLY LATER FRIDAY NIGHT INTO SATURDAY.
RE-AMPLIFICATION OF EASTERN CONUS TROUGH REMAINS A CONSISTENT SIGNAL
IN MODEL GUIDANCE SUNDAY INTO EARLY NEXT WEEK. COLD FRONT ON LEADING
EDGE OF HEIGHT FALLS MAY SUPPORT ANOTHER ROUND OF CONVECTION LATER
SATURDAY NIGHT-SUNDAY DEPENDING ON TIMING. UNSEASONABLY COOL AND
MAINLY DRY WX LIKELY RETURNS EARLY NEXT WEEK.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z WEDNESDAY EVENING)
ISSUED AT 727 PM EDT TUE JUL 22 2014
CHALLENGE OVERNIGHT IS IF CONVECTION WILL FIRE ALONG APPROACHING
COLD FRONT AND IF SO...HOW WIDESPREAD IT WILL BE. LATEST SATELLITE
AND RADAR COMPOSITES SHOWING LINE TRYING TO DEVELOP OVER CENTRAL
LAKE MICHIGAN INTO WISCONSIN WITH AN AREA OF SHOWERS FURTHER SOUTH
ACROSS IL. WILL KEEP PREVIOUS IDEA OF TAFS INTACT BUT DID ADD A
VCTS TO KSBN GIVEN LATEST HIRES GUIDANCE HANDLING OF CURRENT
WEATHER WITH INDICATION OF FURTHER DEVELOPMENT ALONG BOUNDARY.
QUESTIONS REMAIN ON WHETHER ANY ACTIVITY WILL REACH KFWA AND IMPACT
OPERATIONS. HAVE KEPT MVFR CIG THERE WITH STRATOCU DEVELOPMENT
ALONG FRONT BUT OPTED TO KEEP PCPN OUT OF FORECAST UNTIL WE SEE
HOW DEVELOPMENT OCCURS NEXT FEW HOURS. VFR WEDNESDAY POST FRONTAL
WITH NW WINDS IN THE 10 TO 15 KNOT RANGE.
&&
.IWX WATCHES/WARNINGS/ADVISORIES...
IN...BEACH HAZARDS STATEMENT FROM 3 AM CDT WEDNESDAY THROUGH THURSDAY
MORNING FOR INZ003.
MI...BEACH HAZARDS STATEMENT FROM 4 AM EDT WEDNESDAY THROUGH THURSDAY
MORNING FOR MIZ077.
OH...NONE.
LM...SMALL CRAFT ADVISORY FROM 4 AM WEDNESDAY TO 8 AM EDT THURSDAY
FOR LMZ043-046.
&&
$$
SYNOPSIS...OBERGFELL
SHORT TERM...JAL
LONG TERM...STEINWEDEL
AVIATION...LASHLEY
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 DODGE CITY KS
747 PM CDT Tue Jul 22 2014
...Update for trends and headlines...
.UPDATE...
ISSUED AT 747 PM CDT TUE JUL 22 2014
Executing a bunch of superficial/minor tweaks... 1) will allow the heat
advisory to expire at 8 PM CDT. 2) feeble showers have tried to develop
across Rush county this evening, but are not developing vertically any
more. Looks very weak visually and have removed pops for this evening.
The HRRR suggests more convection, but this model is initializing poorly.
3) updated the HWO and EHWO. 4) running the usual ESTF grids to get
hourly t`s and sky grids in line with reality.
&&
.SHORT TERM...(This evening through Wednesday)
ISSUED AT 1234 PM CDT TUE JUL 22 2014
The upper level high pressure system over Colorado and New Mexico
will not be going anywhere over the next two days. A cold front was
draped south across northern Kansas late this morning, with a
surface low pressure system over eastern Colorado. The cold front
will sag slowly south today, and be just north of the I-70
interstate by 7 pm CDT. This front should serve as a convergence
zone, as well as will the trough near the Colorado border. We have
small 20 percent Pops in our west and northerly zones after 23z
today/tonight, extending in the north through about midnight. The
chances are small, but if any storm does break through the cap, they
will likely be high based and with mainly down burst, strong winds
as hazards. The surface is heating up nicely and highs today should
reach the forecasted maxes of 100 to 102F. I plan to keep the Heat
Advisory ongoing through 8 pm, as currently forecast, and will
update it shortly. The convective temp from the DDC 12Z RAOB
showed 98F. I Will brief the next shift on the high based storm
low chances and the main threat being down burst winds.
There will be a few clouds tonight, resulting in partly cloudy
skies. Minimum temperatures should be from near 70F in the west
along the Colorado border, to the mid 70s in the Coldwater and
Medicine lodge areas. Again, the small chances for thunderstorms
will continue through midnight in our northern counties.
The cold front will push south to near our southern border with
Oklahoma Wednesday. This should allow slightly cooler air and some
high level clouds to cover our CWA. Max temperatures will lower
from the past two days, into the mid 90s north of I-70 to the
upper 90s in our south along the Oklahoma border. Winds on
Wednesday should be from the east at 5 to 20 mph.
.LONG TERM...(Wednesday night through Tuesday)
ISSUED AT 342 PM CDT TUE JUL 22 2014
Upper level ridging will build back into the high plains region for
Thursday and into the weekend. With renewed surface troughing over
western Kansas, high temperatures ought to warm back to the high
90s, with possibly some readings over 100F. Little in the way of
thunderstorm activity is expected, although isolated thunderstorms
can`t be ruled out, particularly in far western Kansas with
elevated heating. The next cold front is expected to pass through
western Kansas by Saturday night as an upper level system over the
northwestern United States passes over the upper level ridge into
the Great Lakes. High temperatures ought to drop at least several
degrees by Sunday to the lower and mid 90s, and probably to around
90F by Monday and Tuesday. There will be small chances for
thunderstorms as the front passes and even behind the front into
Monday. A large upper level trough will persist over the upper
Midwest and Great Lakes regions through the remainder of next
week, resulting in a continued break from the hot temperatures.
There will be small chances for thunderstorms given the lack of
mid level capping; but it appears as though the upper level
pattern may be too amplified for sufficient lee troughing and
destabilization in the presence of the northwesterly mid to upper
level flow.
&&
.AVIATION...(For the 00Z TAFS through 00Z Wednesday evening)
ISSUED AT 600 PM CDT TUE JUL 22 2014
VFR conditions expected through TAF pd. Thunderstorms are not expected
to impact the terminals tonight. A backdoor cold front will move across
the terminals tomorrow morning with southerly winds eventually becoming
NNE/NE. Magnitudes generally under 12 kt through TAF pd.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 71 96 70 100 / 10 10 10 10
GCK 70 97 70 101 / 10 10 10 10
EHA 68 98 70 100 / 10 10 10 10
LBL 70 98 70 101 / 10 10 10 10
HYS 72 94 70 99 / 10 10 10 10
P28 74 98 72 99 / 10 10 10 10
&&
.DDC WATCHES/WARNINGS/ADVISORIES...
HEAT ADVISORY until 8 PM CDT this evening FOR KSZ030-031-046-065-
066-081-089-090.
&&
$$
UPDATE...Sugden
SHORT TERM...Burke
LONG TERM...Finch
AVIATION...Sugden
AREA FORECAST DISCUSSION
NWS GOODLAND KS
554 PM MDT TUE JUL 22 2014
.UPDATE...
ISSUED AT 552 PM MDT TUE JUL 22 2014
UPDATED TO REMOVE THE HEAT ADVISORY SINCE TEMPERATURES ARE ON THE
DECLINE.
&&
.SHORT TERM...(THIS EVENING THROUGH WEDNESDAY)
ISSUED AT 1255 PM MDT TUE JUL 22 2014
18Z WATER VAPOR IMAGERY INDICATED LARGE UPPER LEVEL RIDGE CENTERED
OVER NEW MEXICO WITH RUC ANALYSIS INDICATING A 600 DM RIDGE IN
PLACE AT H5. AT THE SFC...OUTFLOW BOUNDARY HAS STALLED ACROSS THE
EXTREME SOUTHERN CWA...BETWEEN TRIBUNE AND LEOTI EXTENDING
NORTHEAST TOWARDS HILL CITY.
MAIN CONCERNS FOR THE SHORT TERM WILL BE TEMPS AND PRECIP CHANCES
THIS EVENING AND TOMORROW AFTERNOON.
LACK OF ANY MEANINGFUL CU FIELD AT 19Z LOWERS OVERALL CONFIDENCE
IN LATE AFTERNOON THUNDERSTORM FORECAST AND WHILE AN ISOLATED
STORM IS STILL POSSIBLE...HAVE DOUBTS THAT ANYTHING WILL FIRE
ALONG REMAINING OUTFLOW BOUNDARY. WITH H85-H7 WAA INCREASING
TONIGHT...IT WILL BE POSSIBLE FOR STORMS COMING OUT OF THE
NORTHWEST TO MAINTAIN THEMSELVES BUT WITH WEAK WINDS THROUGHOUT
THE COLUMN STORM MOTION WOULD BE SLOW. A FEW MODELS SUGGEST
ELEVATED CONVECTION DEVELOPING AFTER 06Z AND WHILE THE FORCING
WILL BE THERE...CONDENSATION PRESSURE DEFICITS AND PRESSURE
ADVECTION VALUES ON 310 AND 315K SURFACES WOULD SUGGEST SATURATION
UNLIKELY. IF STORMS/CLOUDS CANNOT DEVELOP...BACKED EASTERLY FLOW
WITH A 100MB POCKET OF LOW LEVEL MOISTURE WOULD SUPPORT AT LEAST
PATCHY FOG PRIOR TO 15Z. GENERAL CONSENSUS OF MODELS SUGGESTS
TEMPERATURES AROUND 5 DEGREES COOLER ON WEDNESDAY THAN
TODAY...GIVEN EXPECTED SFC PATTERN THAT APPEARS REASONABLE.
.LONG TERM...(WEDNESDAY NIGHT THROUGH TUESDAY)
ISSUED AT 231 PM MDT TUE JUL 22 2014
A RIDGE OVER THE ROCKIES/PLAINS WILL SHIFT TO THE DESERT SOUTHWEST
BY FRIDAY. A SURFACE TROUGH WILL BE IN EASTERN COLORADO FROM
WEDNESDAY NIGHT UNTIL IT SHIFTS INTO SOUTHWEST KANSAS FRIDAY.
THE SURFACE TROUGH WILL FOCUS THUNDERSTORM DEVELOPMENT WEDNESDAY
EVENING. A SHORTWAVE MOVES INTO THE AREA WILL PROVIDE FORCING. CAPE
WILL RANGE FROM 1000 TO 2000J/KG AND SHEAR WILL BE 20KTS. FORECAST
SOUNDINGS INDICATE AN OVERALL LACK OF MID LEVEL MOISTURE SO WILL
CONTINUE SLIGHT CHANCE POPS.
FOR THURSDAY AFTERNOON AND EVENING, THE SURFACE TROUGH WILL BE
ORIENTED ACROSS NORTHWEST KANSAS BUT ONCE AGAIN FORECAST SOUNDINGS
SHOW HIGH BASED MOISTURE AROUND 600MB. CAPE RANGES FROM 200J/KG IN
EASTERN COLORADO TO 800J/KG IN THE EAST. DUE TO THESE MARGINAL
PARAMETERS WILL STAY WITH SLIGHT CHANCE POPS WITH COVERAGE OVER THE
ENTIRE FA AS THE TROUGH SHIFTS SOUTH DURING THE EVENING.
SURFACE CONVERGENCE AND HEATING WILL BE THE MAIN FORCING FRIDAY
AFTERNOON WITH THE TROUGH WELL TO THE SOUTH OF THE FA. STORMS SHOULD
INITIATE ON THE HIGHER TERRAIN IN EASTERN COLORADO WHERE LIFT WILL BE
MAXIMIZED. SLIGHT CHANCE POPS WILL CONTINUE FOR FRIDAY AFTERNOON.
MAX TEMPERATURES WILL REACH THE UPPER 90S THURSDAY AND FRIDAY. MIN
TEMPERATURES WILL COOL TO THE UPPER 60S WITH AROUND 70 IN THE EAST.
IN THE EXTENDED...(FRIDAY NIGHT THROUGH TUESDAY)...
THE RIDGE OVER THE SOUTHERN ROCKIES WITH SHIFT TO THE DESERT
SOUTHWEST BY SATURDAY AND CONTINUE THROUGH TUESDAY. THERE IS A
SLIGHT CHANCE OF THUNDERSTORMS FRIDAY/SATURDAY WITH STORMS
DEVELOPING DUE TO UPSLOPE WIND/SURFACE CONVERGENCE OVER THE HIGHER
TERRAIN IN EASTERN COLORADO. THESE STORMS WILL MOVE SLOWLY EAST
INTO NORTHWEST KANSAS. NUMEROUS WEAK DISTURBANCES IN NORTHWEST FLOW
WILL PROVIDE FORCING FOR AT LEAST A SLIGHT CHANCE/CHANCE OF
THUNDERSTORMS EACH DAY FROM SUNDAY THROUGH TUESDAY.
MIN TEMPERATURES WILL RANGE FROM 65 TO 70 FRIDAY AND SATURDAY NIGHTS
COOLING TO THE MID 60S SUNDAY AND MONDAY NIGHTS. MAX TEMPERATURES
WILL REACH THE MID 90S SATURDAY COOLING TO THE UPPER 80S FROM SUNDAY
THROUGH TUESDAY.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z WEDNESDAY EVENING)
ISSUED AT 552 PM MDT TUE JUL 22 2014
CONDITIONS SHOULD REMAIN VFR WITH THE POSSIBILITY OF PATCHY FOG
DEVELOPING MAINLY ACROSS SOUTH CENTRAL NEBRASKA AND NORTH CENTRAL
KANSAS BETWEEN 10Z-14Z.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
UPDATE...LOCKHART
SHORT TERM...JRM
LONG TERM...FS
AVIATION...LOCKHART
AREA FORECAST DISCUSSION...UPDATED
NWS JACKSON KY
1041 PM EDT TUE JUL 22 2014
.UPDATE...
ISSUED AT 1040 PM EDT TUE JUL 22 2014
THE SHOWERS HAVE DRIED UP ACROSS THE ENTIRE AREA BESIDES A SMALL CELL
OVER NORTHERN PULASKI COUNTY. THIS WILL DIMINISH THROUGH 11
PM...LEAVING MOSTLY CLEAR TO PARTLY CLOUDY SKIES OVERHEAD FOR THE
MAJORITY OF THE OVERNIGHT. EXPECT MOISTURE TO INCREASE BETWEEN 4 AND
8 AM...WITH PERHAPS A SMALL UPTICK IN CONVECTIVE ACTIVITY THREATENING
ALONG THE SOUTHEAST TERRAIN. THE LATEST HRRR IS SUGGESTING SOME
ACTIVITY MAKING IT IN FROM THE NORTHWEST BEFORE DAWN...HOWEVER THE
CONVECTIVE OUTCOME LOOKS A BIT QUICK ACCORDING TO THE LATEST
SATELLITE TRENDS...SO STUCK WITH THE INHERITED DRY POPS IN THE
BLUEGRASS FOR NOW. BALMY LOWS OF AROUND THE 70 DEGREE MARK FOR MOST
LOCATIONS STILL LOOK ON TARGET. DID INCORPORATE THE LATEST HOURLY
OBSERVATIONS INTO THE DIURNAL DROP OFF FOR THE REST OF THE NIGHT.
UPDATES HAVE BEEN SENT.
UPDATE ISSUED AT 817 PM EDT TUE JUL 22 2014
CONVECTION IS ON THE DECLINE WITH THE LOSS OF HEATING. WILL HANG ONTO
ISOLATED SHOWERS AND A RUMBLE OF THUNDER FOR ANOTHER HOUR OR TWO...
BEFORE A LULL IS THEN EXPECTED INTO THE OVERNIGHT. AS WEAKER
SOUTHWEST FLOW ENGAGES IN TH LOW LEVELS TOWARDS DAWN...THERE MAY BE A
SMALL INCREASE IN CONVECTION ONCE AGAIN...WHICH THE CURRENT FORECAST
ALREADY HAS WELL IN HAND. UPDATES HAVE BEEN SENT.
&&
.SHORT TERM...(THIS EVENING THROUGH WEDNESDAY NIGHT)
ISSUED AT 420 PM EDT TUE JUL 22 2014
AS OF LATE AFTERNOON...AN UPPER LEVEL LOW IS MEANDERING ALONG THE
GULF COAST WHILE THE EASTERN EXTENT OF AN UPPER LEVEL RIDGE CENTERED
NEAR THE FOUR CORNERS REGION EXTENDS INTO THE LOWER OH VALLEY REGION.
A SHORTWAVE IS ROTATING ACROSS THE NORTHERN GREAT LAKES AND ONTARIO
WITH ANOTHER UPSTREAM ENTERING NORTHWEST ONTARIO.
THE SHORTWAVES WILL COMBINE TO HELP FORM AN EASTERN CONUS TROUGH
THROUGH THE PERIOD WHILE THE RIDGE AMPLIFIES ACROSS THE ROCKIES. A
SFC LOW ASSOCIATED WITH THE DEVELOPING TROUGH WILL TRACK FROM JUST
NORTH OF THE NORTHERN GREAT LAKES AND INTO THE MARITIMES THROUGH WED
NIGHT WITH THE DEVELOPING TROUGH AND NORTHWEST FLOW PUSHING THE
TRAILING COLD FRONT INTO THE OH VALLEY LATE TONIGHT INTO THE DAY ON
WED. THIS FRONT WILL GRADUALLY CROSS THE REGION LATE ON WED AFTERNOON
INTO WED EVENING.
IN THE MEANTIME...ISOLATED SHOWERS AND POSSIBLY A STRAY THUNDERSTORM
WILL REMAIN POSSIBLE MAINLY UNTIL NEAR SUNSET AND DAYTIME HEATING IS
LOST. THERE WILL BE SOME MINOR HEIGHT FALLS OVERNIGHT AND WITH A
MOIST AIR MASS IN PLACE...A STRAY SHOWER CANNOT BE RULED OUT
OVERNIGHT...BUT THIS WOULD BE FEW AND FAR BETWEEN OTHERWISE...THE
CONSECUTIVELY DRIVEN CU SHOULD DISSIPATE OVERNIGHT AND PATCHY RIVER
VALLEY FOG IS AGAIN ANTICIPATED.
MORE ORGANIZED CONVECTION IS ANTICIPATED AS THE FRONT APPROACHES AND
CROSSES THE REGION AND THE UPPER LEVEL TROUGH DEVELOPS OVER THE
EASTERN CONUS. THIS FRONT AND UPPER LEVEL FORCING FROM THE DEVELOPING
TROUGH WILL INTERACT WITH A MOIST PREFONTAL AIR MASS TO BRING MORE
ORGANIZED CONVECTION TO THE REGION FROM WED AFTERNOON INTO WED NIGHT.
MORNING HEATING WILL BE DE PENDANT ON HOW MUCH CLOUD COVER THERE IS IN
THE AM AND THIS WILL ULTIMATELY DETERMINE INSTABILITY. MODERATE
INSTABILITY IS ANTICIPATED WITH TEMPS IN THE MID 80S TO AROUND 90 AND
DEWPOINTS IN THE UPPER 60S TO AROUND 70. THE LOW LEVEL GRADIENT WILL
BE RATHER WEAK AND SO WILL THE WINDS WHILE THE UPPER LEVEL WINDS WILL
NOT BE ALL THAT STRONG SO SHEAR WILL BE WEAK. PWS IS PROGGED TO CLIMB
1.5 TO 1.8 INCH RANGE FROM MIDDAY WED INTO WED NIGHT...SO STORMS
SHOULD BE ABLE TO PRODUCE LOCALLY HEAVY RAIN. A STRONGER STORM OR TWO
MIGHT ALSO BE ABLE TO PRODUCE STRONG WIND GUSTS. ONCE THE FRONT
CROSSES THE REGION...INSTABILITY WILL DIMINISH AND THE THREAT FOR
THUNDER SHOULD ALSO DIMINISH LATE WED NIGHT.
TEMPS WILL CONTINUE TO BE ABOVE NORMAL THROUGH THE PERIOD...BUT A
COLDER AND DRIER AIR MASS WILL ALREADY BE STARTING TO ADVECT INTO THE
AREA LATE IN THE PERIOD.
.LONG TERM...(WEDNESDAY NIGHT THROUGH MONDAY)
ISSUED AT 348 AM EDT TUE JUL 22 2014
THE MODELS ARE IN ONLY FAIR AGREEMENT ALOFT THROUGH THE EXTENDED
PORTION OF THE FORECAST. WHILE THEY ALL DEPICT THE ABNORMAL PATTERN
OF A STRONG FOUR CORNERS REGION RIDGE AND DEEP TROUGHING IN THE EAST
CONTINUING THROUGH THE END OF THE WEEK AND INTO THE START OF THE
NEXT WEEK...THEY DIFFER ON THE MAGNITUDE AND TIMING OF THE EVOLVING
EASTERN TROUGH...PARTICULARLY OVER THE WEEKEND AND INTO MONDAY.
SPECIFICALLY...FALLING HEIGHTS OVER KENTUCKY WILL BE THE RULE INTO
THURSDAY NIGHT AS THE RETROGRADING LOW TO THE SOUTH PULLS AWAY AND
THE NORTHERN STREAM SENDS A SERIES OF SHORTWAVES THROUGH THE AREA IN
NORTHWEST FLOW. THIS EASTERN TROUGH PULLS AWAY TO START THE WEEKEND
WITH HEIGHTS CLIMBING TEMPORARILY BEFORE THEY FALL AGAIN IN THE FACE
OF A NODE OF THE LARGE NORTHEAST TROUGH GEARING UP FOR A DIVE INTO
THE UPPER MIDWEST AND OHIO VALLEY. THE 00Z GFS IS MOST AGGRESSIVE
WITH THIS EVOLUTION WHILE THE 12 ECMWF KEEPS ITS CORE WAVE FURTHER
TO THE NORTHWEST AND LAGS THE GFS DEVELOPMENT. HOWEVER...THE LATEST
CMC AND ECMWF ARE TRENDING MORE TOWARD THE GFS. REGARDLESS...
NORTHWEST FLOW WILL DOMINATE THE LOCAL PATTERN AS HEIGHTS FALL INTO
MONDAY MORNING. EVENTUALLY...THE ECMWF CATCHES UP...WITH THE DEEPER
AND MORE WESTERN TROUGH IDEA OF THE GFS BUT SOME SIGNIFICANT
DIFFERENCES REMAIN WITH THE PATTERN OVER THE OHIO VALLEY TO CLOSE
OUT THE WEEK. THE BETTER AGREEMENT EARLIER IN THE EXTENDED SUPPORTS
A BLENDED SOLUTION WHILE THE LARGER SPREAD LATER ON LOWERS
CONFIDENCE SO THAT THE ENSEMBLES AND A SLIGHT LEAN TOWARD THE GFS
ARE PREFERRED SOLUTIONS.
SENSIBLE WEATHER WILL FEATURE AN APPROACHING COLD FRONT SERVING AS A
FOCUSING MECHANISM FOR SHOWERS AND THUNDERSTORMS WEDNESDAY NIGHT
INTO THURSDAY. COOLER AND DRIER AIR WILL FILTER INTO THIS PART OF
THE STATE LATER IN THE DAY THURSDAY PUTTING AN END TO THE CONVECTIVE
CHANCES FROM NORTHWEST TO SOUTHEAST. DRY AND RELATIVELY COOL WEATHER
FOLLOWS INTO THE START OF THE WEEKEND THANKS TO A BRIEF VISIT OF
HIGH PRESSURE. HOWEVER...THE COLD FRONT THAT BROUGHT THE DRIER
WEATHER WILL START TO SURGE NORTH OVER THE WESTERN PARTS OF THE
REGION AND BRING WARMTH...MOISTURE...AND BETTER CONVECTIVE CHANCES
BACK INTO THE AREA ON SATURDAY. A SERIES OF SHORT WAVES AT MID
LEVELS...THE DEVELOPING TROUGH...AND THE SFC FRONTAL STRUCTURE OVER
THE OHIO VALLEY KEEP SHOWER AND THUNDERSTORM CHANCES GOING INTO
SUNDAY AND MONDAY.
THE CR GRID LOAD PROVIDED A DECENT START TO THE FORECAST FOR THE
EXTENDED...THOUGH DID ADJUST THE POPS TO ADD A TINGE OF DIURNAL TO
THE TIMING OF THE CONVECTION. ALSO...TWEAKED THE LOW TEMPERATURE
GRIDS A TAD TO REFLECT RIDGE AND VALLEY DIFFERENCES WEDNESDAY AND
THURSDAY NIGHT.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z WEDNESDAY EVENING)
ISSUED AT 817 PM EDT TUE JUL 22 2014
A ROGUE SHOWER WILL AFFECT SME FROM THE EAST THROUGH 0030Z BEFORE
DISSIPATING...OTHERWISE CONVECTION WILL BE ON THE WANE THROUGH THE
OVERNIGHT WITH IFR TO MVFR FOG ONCE AGAIN TO CONTEND WITH BETWEEN 06
AND 12Z. EXPECT THAT THE DEEPER VALLEYS WILL SEE THE LIFR OR WORSE
CONDITIONS...WITH BETTER CONDITIONS IN THE BROADER VALLEYS AND
RIDGETOPS. SME COULD BE IN FOR IFR OR WORSE FOG DEPENDING ON THE
RAINFALL AMOUNTS THAT OCCUR THERE. ISOLATED CONVECTION WILL THREATEN
ONCE AGAIN BY AROUND 12Z...WITH BETTER CHANCES OCCURRING IN THE
AFTERNOON WITH THE APPROACH OF A COLD FRONT FROM THE NORTHWEST. LIGHT
SOUTH TO SOUTHWEST WINDS WILL SHIFT TO THE WEST AND NORTHWEST
WEDNESDAY AFTERNOON.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...GEOGERIAN
SHORT TERM...JP
LONG TERM...GREIF
AVIATION...GEOGERIAN
AREA FORECAST DISCUSSION
NWS JACKSON KY
335 PM EDT MON JUL 21 2014
.UPDATE...
ISSUED AT 1035 AM EDT MON JUL 21 2014
HOURLY GRIDS HAVE BEEN UPDATED BASED ON RECENT OBSERVATION...SATELLITE
AND RADAR TRENDS. 12Z RAOBS FORM ILN...OHX...AND RNK ALL HAVE A RATHER
WARMER MID LEVEL TEMPS NEAR 600 MB. 12Z NAM AND ITS FORECAST
SOUNDINGS ARE SIGNIFICANTLY WARM AND MOIST THAT PARCELS AND THUS
CU MIGHT BE ABLE TO RISE PAST THIS WARM AIR FOR SOME ISOLATED
SHRA/TSRA. HOWEVER...THIS SCENARIO POINTS MORE TOWARDS A CONSIDERABLE
AMOUNT OF CU DEVELOPING 15Z TO 19Z...WHICH COULD EVENTUALLY JUST MIX
OUT BY EVENING.
THE 12Z NAM HAS THE ONLY VERY LIMITED CONVECTION DEVELOPING IN THE
HIGHEST TERRAIN. RECENT HRRR RUN AND RECENT RAP RUNS ALSO HAVE VERY
LIMITED COVERAGE OF CONVECTION LATER ON. THE 9Z SREF HAS THE HIGHEST
PROBABILITIES ACROSS THE VA BORDER COUNTIES. WITH THE CURRENT WARM
MID LEVEL AIR EXPECTED TO LARGELY PERSIST...CONVECTIVE COVERAGE MAY
END UP LOWER THAN THE CURRENT FORECAST OR POSSIBLY NIL OUTSIDE OF THE
TN AND VA BORDER COUNTIES FROM WHITLEY EAST AND NORTHEAST TO PIKE.
ATTM...WE WILL GO WITH PERSISTENCE FOR AFTERNOON POPS AND CONTINUE TO
EVALUATE CONVECTIVE TRENDS.
OVERALL...TODAY WILL CONTINUE THE WARMING TRENDS WITH RATHER HUMID
CONDITIONS.
UPDATE ISSUED AT 637 AM EDT MON JUL 21 2014
THE FEW SPRINKLES OVER THE AREA HAS DISSIPATED THIS MORNING SO HAVE
TAKEN THEM OUT AND ADJUSTED FOR THE CURRENT OBSERVATIONS. DENSE FOG
STILL APPEARS TO BE LINGERING IN SOME SPOTS SO WILL LEAVE IT IN THE
FORECAST THROUGH THE MID MORNING HOURS. HAVE LOADED THE LATEST OBS
AND UPDATED THE ZFP TO TAKE OUT SPRINKLES AND UPDATE THIS MORNINGS
LOWS.
&&
.SHORT TERM...(TODAY THROUGH TUESDAY)
ISSUED AT 342 AM EDT MON JUL 21 2014
A VERY WARM...MOIST...AND UNSTABLE SHORT TERM PERIOD LOOKS TO BE THE
SCENARIO FOR EASTERN KENTUCKY. CONDITIONS ACROSS THE AREA AS OF 07Z
FEATURE SOME FOG DEVELOPMENT IN THE DEEPER VALLEYS. THIS IS MAINLY
WHERE SKIES HAVE CLEARED OUT FROM THE CLOUD COVER ASSOCIATED WITH
THE PREVIOUS EVENINGS CONVECTION. WHERE THIS HAS OCCURRED...MAY NEED
SOME HEADLINE ISSUED FOR THE DENSE FOG DEVELOPMENT. CLOUD COVER SHOULD
REMAIN PRETTY PERSISTENT INTO THE MORNING OVER THE EAST. LOWS ONLY
DROPPING INTO THE MID 60S THIS MORNING ALONG WITH MID 60 DEW POINTS
WILL MAKE FOR A RATHER UNCOMFORTABLE MORNING. EVEN NOW...WITH THIS
JUICY AIR MASS...A FEW WEAK SHOWERS ARE STILL DEVELOPING MAINLY OVER
THE EAST.
THE DEVELOPMENT OF THIS SCENARIO LIES WITH A PINCHED OFF UPPER LOW
THAT WILL BECOME CUT OFF FROM THE UPPER LEVEL FLOW OVER THE NORTHERN
CONUS. THE MODELS CONTINUE TO SHOW THIS FEATURE ENHANCING CONVECTION
ACROSS THE SOUTHEAST BUT ALSO INTO THE APPALACHIAN REGION. THIS ALONG
WITH THE UPPER LEVEL RIDGE OVER THE SOUTHEAST SLIDING EAST INTO THE
BAHAMAS ALLOWS FOR AN INCREASED SOUTHERLY RETURN FLOW INTO THE
SOUTHEASTERN CONUS AND INTO THE APPALACHIANS. THIS PATTERN CONTINUES
TO LEAVE EASTERN KENTUCKY UNDER VERY WEAK FLOW.
THAT SAID...LOOKING AT THE LOWER LEVELS...BOTH THE GFS AND NAM AGREE
WITH QUITE A BIT OF INSTABILITY AVAILABLE WITH CAPE VALUES REACHING
2500 J/KG BOTH THIS AFTERNOON AND TUESDAY AFTERNOON...THIS WITH PWATS
IN THE 1.50 TO 1.75 INCH RANGE BOTH DAYS AND WEAK FLOW WILL LEAD TO
SOME CONCERNS WITH SLOW MOVING STORMS PRODUCING HEAVY RAIN. THE ONE
SAVING GRACE HERE IS THE UPPER DISTURBANCE IS STILL CENTERED OVER THE
GULF COAST STATES BUT SOME ENERGY FROM THE LOW ON THE NORTHERN FRINGE
LOOKS TO MAKE IT INTO THE CENTRAL APPALACHIAN CHAIN AND INTO SOUTHEASTERN
KENTUCKY. THIS UNCERTAINTY WITH A GOOD TRIGGER HERE KEEPS FROM GOING
LIKELY POPS BUT STILL WILL KEEP SLIGHT CHANCE TO CHANCE FROM WEST TO
EAST AND GOING WITH AERIAL COVERAGE BOTH DAYS AS WITH THE TYPE OF
MOIST AND UNSTABLE AIR MASS IN PLACE...NOT MUCH SUPPORT IS NEEDED FOR
STORM DEVELOPMENT. MAY NEED TO MENTION SOME THREAT OF SLOW MOVING
STORMS IN THE HWO...MAINLY FOR TUESDAY WITH THE BETTER SUPPORT MAKING IT
INTO THE AREA.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 335 PM EDT MON JUL 21 2014
THE MID TERM WILL FOCUS AROUND A SURFACE COLD FRONT MOVING FROM NW
TO SE ACROSS THE REGION. WINDS FLOWING SOUTHERLY UP UNTIL THIS POINT
WILL BEGIN TO SWITCH TO A MORE WRLY DIRECTION JUST AHEAD OF THE
FRONTAL PASSAGE. STILL...MOIST AND UNSTABLE AIR ACROSS THE
REGION...AS WELL AS THE INCOMING LIFTING SOURCE WILL BE ENOUGH TO
PRODUCE WIDESPREAD SHOWERS AND THUNDERSTORMS ACROSS MUCH OF THE
REGION DURING THE DAYTIME HOURS WEDNESDAY. WITH CAPES WELL ABOVE
2000 J/KG AFTER 12Z...AND GOOD MID LEVEL DRY AIR...COULD BE A GOOD
SCENARIO FOR SOME DECENT CONVECTION. MODELS ARE ALL IN FAIRLY GOOD
AGREEMENT ABOUT THE ONSET OF PRECIP BETWEEN 15 AND 18Z IN THE
NORTHERN COUNTIES...WITH SOME DIURNAL SCATTERED CONVECTION POPPING
UP ACROSS EASTERN KY AFTER 12Z AHEAD OF THE MAIN LINE. AS THE FRONT
SLOWLY TRAVERSES KY...EXPECT PRECIP TO LINGER INTO THE OVERNIGHT
HOURS WEDNESDAY NIGHT AND INTO THE DAY THURSDAY. LOSS OF MID LEVEL
DRY AIR OVERNIGHT WEDNESDAY NIGHT WILL CUT DOWN ON SOME OF THE BEST
CONVECTION AND HAIL POTENTIAL...BUT EXPECT IT TO RETURN AGAIN BY
THURSDAY AND CONTINUE INTO THE OVERNIGHT HOURS THURSDAY NIGHT. BY
FRIDAY...THE FRONT WILL FINALLY EXIT TO OUR SE. THOUGH SOME UPSLOPE
CONVECTION MAY LINGER IN THE FAR SE...OVERALL DRIER AIR SHOULD
FILTER IN AND CUT OFF ANY REMAINING PRECIP CHANCES DURING THE DAY
FRIDAY.
TEMPS WEDNESDAY LEADING INTO THE FRONTAL PASSAGE WILL BE QUITE WARM
AND HUMID...WITH HIGHS TIPPING 90 DEGREES IN SOME LOCATIONS ACROSS
EASTERN KY. BY THURSDAY HOWEVER...COOLER AIR WILL BEGIN FILTERING IN
THANKS TO A SURFACE HIGH PRESSURE TO OUR NORTH...WITH HIGHS ONLY
EXPECTED TO REACH AROUND 80.
FOR THE REMAINDER OF THE EXTENDED...A STRONG RIDGE OVER THE SW
CONUS...AND A TROUGH OVER THE EASTERN CONUS WILL BE THE MAIN PLAYERS
IN OUR WEATHER. ALTHOUGH THE TROUGH WILL WORK TO BECOME LESS
AMPLIFIED BY LATE THE PERIOD...EXPECT SEVERAL SHORTWAVES TO RIDE
ALONG THE TROUGH AND BRING PRECIP CHANCES TO THE OHIO RIVER VALLEY
REGION. THE FIRST OF THESE WILL BRING SHOWERS AND THUNDERSTORMS TO
EASTERN KY BY SATURDAY AFTERNOON/NIGHT. CHANCES SHOULD THEN CONTINUE
THROUGH THE REMAINDER OF THE PERIOD. TEMPS WILL SLOWLY RISE BACK
INTO THE MID 80S WITH HIGHER HUMIDITY VALUES BY THE WEEKEND...THEN
WILL COOL SLIGHTLY AS ANOTHER COLD FRONT ACCOMPANIES THE PRECIP
CHANCES SUNDAY NIGHT/MONDAY.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z TUESDAY MORNING)
ISSUED AT 637 AM EDT MON JUL 21 2014
EXPECT THE LINGERING FOG TO LIFT BY 14 AND 15Z. A WEAK DISTURBANCE
OVERHEAD ALONG WITH SIGNIFICANT INSTABILITY WILL ALLOW FOR SHOWERS
AND THUNDERSTORMS TO DEVELOP AGAIN INTO THE AFTERNOON AND INTO THE
EVENING. COVERAGE AT THIS POINT APPEARS TO BE IN QUESTION AND SHOWING
SOME CONFIDENCE IN THUNDERSTORMS APPEARING AT THE TAF SITES IS NOT
POSSIBLE. WILL LEAVE THUNDERSTORMS OUT OF THE TAFS BUT MENTION THE
PRESENCE IN THE AFD. WINDS WILL BE LIGHT AND VARIABLE THROUGH THE
PERIOD. FOG WILL DEVELOP AGAIN TONIGHT AND WILL BE DENSE IN SOME
AREAS...ESPECIALLY AREAS THAT RECEIVE RAINFALL. WILL NEED TO PUT
BELOW IFR VISIBILITY VALUES IN THE TAFS.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...JP
SHORT TERM...SHALLENBERGER
LONG TERM...JMW
AVIATION...SHALLENBERGER
AREA FORECAST DISCUSSION...UPDATED
NWS JACKSON KY
1039 AM EDT MON JUL 21 2014
.UPDATE...
ISSUED AT 1035 AM EDT MON JUL 21 2014
HOURLY GRIDS HAVE BEEN UPDATED BASED ON RECENT OBSERVATION...SATELLITE
AND RADAR TRENDS. 12Z RAOBS FORM ILN...OHX...AND RNK ALL HAVE A RATHER
WARMER MID LEVEL TEMPS NEAR 600 MB. 12Z NAM AND ITS FORECAST
SOUNDINGS ARE SIGNIFICANTLY WARM AND MOIST THAT PARCELS AND THUS
CU MIGHT BE ABLE TO RISE PAST THIS WARM AIR FOR SOME ISOLATED
SHRA/TSRA. HOWEVER...THIS SCENARIO POINTS MORE TOWARDS A CONSIDERABLE
AMOUNT OF CU DEVELOPING 15Z TO 19Z...WHICH COULD EVENTUALLY JUST MIX
OUT BY EVENING.
THE 12Z NAM HAS THE ONLY VERY LIMITED CONVECTION DEVELOPING IN THE
HIGHEST TERRAIN. RECENT HRRR RUN AND RECENT RAP RUNS ALSO HAVE VERY
LIMITED COVERAGE OF CONVECTION LATER ON. THE 9Z SREF HAS THE HIGHEST
PROBABILITIES ACROSS THE VA BORDER COUNTIES. WITH THE CURRENT WARM
MID LEVEL AIR EXPECTED TO LARGELY PERSIST...CONVECTIVE COVERAGE MAY
END UP LOWER THAN THE CURRENT FORECAST OR POSSIBLY NIL OUTSIDE OF THE
TN AND VA BORDER COUNTIES FROM WHITLEY EAST AND NORTHEAST TO PIKE.
ATTM...WE WILL GO WITH PERSISTENCE FOR AFTERNOON POPS AND CONTINUE TO
EVALUATE CONVECTIVE TRENDS.
OVERALL...TODAY WILL CONTINUE THE WARMING TRENDS WITH RATHER HUMID
CONDITIONS.
UPDATE ISSUED AT 637 AM EDT MON JUL 21 2014
THE FEW SPRINKLES OVER THE AREA HAS DISSIPATED THIS MORNING SO HAVE
TAKEN THEM OUT AND ADJUSTED FOR THE CURRENT OBSERVATIONS. DENSE FOG
STILL APPEARS TO BE LINGERING IN SOME SPOTS SO WILL LEAVE IT IN THE
FORECAST THROUGH THE MID MORNING HOURS. HAVE LOADED THE LATEST OBS
AND UPDATED THE ZFP TO TAKE OUT SPRINKLES AND UPDATE THIS MORNINGS
LOWS.
&&
.SHORT TERM...(TODAY THROUGH TUESDAY)
ISSUED AT 342 AM EDT MON JUL 21 2014
A VERY WARM...MOIST...AND UNSTABLE SHORT TERM PERIOD LOOKS TO BE THE
SCENARIO FOR EASTERN KENTUCKY. CONDITIONS ACROSS THE AREA AS OF 07Z
FEATURE SOME FOG DEVELOPMENT IN THE DEEPER VALLEYS. THIS IS MAINLY
WHERE SKIES HAVE CLEARED OUT FROM THE CLOUD COVER ASSOCIATED WITH
THE PREVIOUS EVENINGS CONVECTION. WHERE THIS HAS OCCURRED...MAY NEED
SOME HEADLINE ISSUED FOR THE DENSE FOG DEVELOPMENT. CLOUD COVER SHOULD
REMAIN PRETTY PERSISTENT INTO THE MORNING OVER THE EAST. LOWS ONLY
DROPPING INTO THE MID 60S THIS MORNING ALONG WITH MID 60 DEW POINTS
WILL MAKE FOR A RATHER UNCOMFORTABLE MORNING. EVEN NOW...WITH THIS
JUICY AIR MASS...A FEW WEAK SHOWERS ARE STILL DEVELOPING MAINLY OVER
THE EAST.
THE DEVELOPMENT OF THIS SCENARIO LIES WITH A PINCHED OFF UPPER LOW
THAT WILL BECOME CUT OFF FROM THE UPPER LEVEL FLOW OVER THE NORTHERN
CONUS. THE MODELS CONTINUE TO SHOW THIS FEATURE ENHANCING CONVECTION
ACROSS THE SOUTHEAST BUT ALSO INTO THE APPALACHIAN REGION. THIS ALONG
WITH THE UPPER LEVEL RIDGE OVER THE SOUTHEAST SLIDING EAST INTO THE
BAHAMAS ALLOWS FOR AN INCREASED SOUTHERLY RETURN FLOW INTO THE
SOUTHEASTERN CONUS AND INTO THE APPALACHIANS. THIS PATTERN CONTINUES
TO LEAVE EASTERN KENTUCKY UNDER VERY WEAK FLOW.
THAT SAID...LOOKING AT THE LOWER LEVELS...BOTH THE GFS AND NAM AGREE
WITH QUITE A BIT OF INSTABILITY AVAILABLE WITH CAPE VALUES REACHING
2500 J/KG BOTH THIS AFTERNOON AND TUESDAY AFTERNOON...THIS WITH PWATS
IN THE 1.50 TO 1.75 INCH RANGE BOTH DAYS AND WEAK FLOW WILL LEAD TO
SOME CONCERNS WITH SLOW MOVING STORMS PRODUCING HEAVY RAIN. THE ONE
SAVING GRACE HERE IS THE UPPER DISTURBANCE IS STILL CENTERED OVER THE
GULF COAST STATES BUT SOME ENERGY FROM THE LOW ON THE NORTHERN FRINGE
LOOKS TO MAKE IT INTO THE CENTRAL APPALACHIAN CHAIN AND INTO SOUTHEASTERN
KENTUCKY. THIS UNCERTAINTY WITH A GOOD TRIGGER HERE KEEPS FROM GOING
LIKELY POPS BUT STILL WILL KEEP SLIGHT CHANCE TO CHANCE FROM WEST TO
EAST AND GOING WITH AERIAL COVERAGE BOTH DAYS AS WITH THE TYPE OF
MOIST AND UNSTABLE AIR MASS IN PLACE...NOT MUCH SUPPORT IS NEEDED FOR
STORM DEVELOPMENT. MAY NEED TO MENTION SOME THREAT OF SLOW MOVING
STORMS IN THE HWO...MAINLY FOR TUESDAY WITH THE BETTER SUPPORT MAKING IT
INTO THE AREA.
.LONG TERM...(TUESDAY NIGHT THROUGH SUNDAY)
ISSUED AT 428 AM EDT MON JUL 21 2014
MODELS ARE IN GOOD AGREEMENT FOR THE PERIOD. ON TUESDAY EVENING SE KY
WILL BE ON THE FRINGE OF AN AREA OF DEEP MOISTURE OVER THE SE CONUS
ASSOCIATED WITH AN UPPER LOW/TROUGH. FEATURES WILL BE WEAK...AND ANY
CONVECTIVE PRECIP SHOULD BE POORLY ORGANIZED SHOULD SHOW A STRONG
DIURNAL TREND. HAVE CARRIED A SLIGHT CHANCE POP FOR ANY PRECIP WHICH
MAY LINGER INTO THE EVENING IN OUR SE COUNTIES.
ON WEDNESDAY...A LARGE MID/UPPER LEVEL TROUGH DROPPING INTO THE NE
CONUS WILL SEND ITS ASSOCIATED COLD FRONT SE INTO KY. THE FRONT WILL
SLOWLY TRANSITION ACROSS THE APPALACHIANS...EMERGING OVER VA AND THE
CAROLINAS FRIDAY. THERE WILL BE A PROLONGED ENHANCEMENT OF POPS FROM
WEDNESDAY THROUGH THURSDAY OVER THE JKL FORECAST AREA...BEFORE DRIER
AIR FINALLY MAKES IT WAY IN FROM THE NORTH BEHIND THE FRONT. DRY
WEATHER IS EXPECTED FROM LATE FRIDAY INTO SATURDAY AS HIGH PRESSURE
MOVES THROUGH THE OHIO VALLEY.
BY SUNDAY...LOW LEVEL FLOW SHOULD AGAIN CARRY A MORE HUMID AIR MASS
BACK INTO THE REGION. AT THE SAME TIME...WHAT WILL BECOME A
SIGNIFICANT UPPER LEVEL TROUGH WILL START TO DEEPEN OVER THE GREAT
LAKES AND OHIO VALLEY. THE COMBINATION WILL RESULT IN ANOTHER
POTENTIAL FOR SHOWERS AND THUNDERSTORMS.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z TUESDAY MORNING)
ISSUED AT 637 AM EDT MON JUL 21 2014
EXPECT THE LINGERING FOG TO LIFT BY 14 AND 15Z. A WEAK DISTURBANCE
OVERHEAD ALONG WITH SIGNIFICANT INSTABILITY WILL ALLOW FOR SHOWERS
AND THUNDERSTORMS TO DEVELOP AGAIN INTO THE AFTERNOON AND INTO THE
EVENING. COVERAGE AT THIS POINT APPEARS TO BE IN QUESTION AND SHOWING
SOME CONFIDENCE IN THUNDERSTORMS APPEARING AT THE TAF SITES IS NOT
POSSIBLE. WILL LEAVE THUNDERSTORMS OUT OF THE TAFS BUT MENTION THE
PRESENCE IN THE AFD. WINDS WILL BE LIGHT AND VARIABLE THROUGH THE
PERIOD. FOG WILL DEVELOP AGAIN TONIGHT AND WILL BE DENSE IN SOME
AREAS...ESPECIALLY AREAS THAT RECEIVE RAINFALL. WILL NEED TO PUT
BELOW IFR VISIBILITY VALUES IN THE TAFS.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...JP
SHORT TERM...SHALLENBERGER
LONG TERM...HAL
AVIATION...SHALLENBERGER
AREA FORECAST DISCUSSION
NWS CARIBOU ME
926 AM EDT MON JUL 21 2014
.SYNOPSIS...
ONE LAST WEAK UPPER LEVEL DISTURBANCE WILL CROSS THE REGION
TODAY AS SURFACE HIGH PRESSURE SETTLES SOUTHEAST OF THE REGION.
A COLD FRONT WILL APPROACH FROM THE NORTH TUESDAY NIGHT...THEN
SLOWLY CROSS THE REGION NORTHWEST TO SOUTHEAST WEDNESDAY AFTERNOON
THROUGH WEDNESDAY NIGHT.
&&
.NEAR TERM /THROUGH TONIGHT/...
900 AM UPDATE: CLD CVR AND FCST HRLY TEMPS TO SLIGHTLY UPWARDS
MODIFIED HI TEMPS WERE ADJUSTED THIS UPDATE TO REFLECT CURRENT
CONDITIONS...WHICH BASED ON SAT IMAGERY...IS SUNNIER ATTM THEN
ANTICIPATED IN PREV FCST UPDATES. AFTN POPS ACROSS WRN PTNS OF
THE FA WERE LOWERED TO ISOLD SHWRS BASED ON HRLY SIMULATED RADAR
REF FROM THE HRRR MODEL...WHICH SHOWED LITTLE IN THE WAY OF SHWRS.
THIS IS LIKELY RELATED TO A MID LVL CAP LCTD BETWEEN 10 TO 15 KFT
AGL...WHICH WILL LARGELY PREVENT FREE CNVCTN THIS AFTN.
ORIGINAL DISC: LOW PRESSURE WILL PASS WELL TO THE SOUTHEAST OF NEW
ENGLAND THIS MORNING. HIGH PRESSURE IS THEN EXPECTED TO BUILD IN
BEHIND THE LOW LATE TODAY AND TONIGHT. EXPECT CLOUDS OVER THE
NORTH TODAY THEN CLEARING TONIGHT AS HIGH PRESSURE BUILDS IN. HAVE
BLENDED THE NAM...GFS...SREF AND ECMWF FOR POPS AND QPF. FOR WIND
HAVE USED THE MOSG25. MAXIMUM AND MINIMUM TEMPERATURE FROM THE
BIAS CORRECTED CONSENSUS ALL.
&&
.SHORT TERM /TUESDAY THROUGH WEDNESDAY/...
VERY WARM AND INCREASINGLY HUMID THROUGH THIS TERM W/CONVECTION A
GOOD POSSIBILITY ON WEDNESDAY.
HIGH PRES IN THE UPPER LEVELS IS EXPECTED TO RIDGE ACROSS THE
REGION ON TUESDAY W/THE MID AND UPPER LEVELS WARMING. THIS WILL
LEAD TO A CAPPING OF THE ATMOSPHERE AND ESSENTIALLY SHUTTING OFF
THE CONVECTIVE POTENTIAL. IN ADDITION, DEWPOINTS WILL BE ON THE
RISE AT THE SURFACE AND W/A DECENT AMOUNT OF SUNSHINE AND SW WINDS
EXPECTED, TEMPERATURES SHOULD WARM WELL INTO THE 80S. THE
EXCEPTION TO THIS WILL BE ALONG THE COAST AS A SSW WIND WILL LEAD
TO TEMPERATURES BEING COOLED FROM THE GULF OF MAINE WATERS.
TUESDAY NIGHT WILL BE A MUGGY NIGHT AS OVERNIGHT LOWS WILL ONLY
DROP BACK INTO THE MID AND UPPER 60S. WEDNESDAY LOOKS LIKE IT WILL
START OUT W/SOME SUNSHINE BY CLOUDS WILL BE ON THE INCREASE BY
LATE MORNING AS THE COLD FRONT APPROACHES FROM THE W. THE
ATMOSPHERE REMAINS WARM ALOFT TO START OUT THE DAY W/A CAP IN PLACE,
BUT AS THE MORNING WEARS ON AND THE FRONT APPROACHES, THIS CAP
LOOKS LIKE IT WILL BE BROKEN. THIS WILL ALLOW FOR CUMULUS TO BUILD
AND CONVECTION TO START FIRING. TIMING AND STRENGTH OF THE
CONVECTION ARE THE BIG QUESTIONS ATTM. THE GFS AND THE NAM ARE
STILL THE FASTEST OF THE GUIDANCE IN BRINGING THE FRONT THROUGH
THE REGION ON WEDNESDAY WHILE THE ECMWF CONTINUES IT COURSE OF
BEING ABOUT 3 HRS SLOWER. GIVEN HOW THE UPPER FLOW ALIGNS W/THE
FRONT, DECIDED TO SLOW THINGS UP A BIT AND ALLOWING FOR MORE
HEATING W/DAYTIME TEMPERATURES HITTING UPPER 80S AWAY FROM THE COAST.
THIS IN TURN WILL LEAD TO THE POTENTIAL FOR ORGANIZED CONVECTION.
SB CAPES ARE FORECAST TO BE IN THE RANGE OF 1200-2000 J/KG W/LIS
-3 TO -5. THERE IS HEALTHY SHEAR IN THE 0-6KM LAYER OF 35+ KTS
W/SOME DIRECTIONAL SHEAR. DEPENDING ON THE GUIDANCE YOU CHOOSE,
0-3KM HELICITY IS FORECAST TO RANGE FROM 150-300 M2/S2 WHICH
POINTS TO SOME ROTATION OF STORMS. PWATS FORECAST TO BE IN 1.5+
INCHES. LLVL LAPSE RATES(0-3KM) ARE PROJECTED TO BE IN THE 7-8
C/KM WHILE THE 85-700MB LAPSE RATES ARE MEAGER W/AROUND 6.0 C/KM.
THIS COULD BE OFFSET HOWEVER BY THE LLVL HEATING IF IT HANGS ON
LONG ENOUGH. ATTM, DECIDED TO KEEP ENHANCED WORDING THE FORECAST
W/HEAVY RAIN, STRONG GUSTY WINDS AND SMALL HAIL. HAIL MIGHT BE
HARD TO COME BY W/FREEZING LEVELS AT 14K FT. WINDS & HEAVY
RAINFALL COULD BE THE GREATER THREAT. DAY3 CONVECTIVE OUTLOOK
FROM SPC HAS THE REGION IN A SLIGHT RISK FOR SEVERE WEATHER.
&&
.LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/...
THE COLD FRONT IS FORECAST TO MAKE ITS WAY SE TOWARD THE MAINE
COAST W/SHOWERS AND TSTMS. CONVECTION SHOULD WIND DOWN BY
MIDNIGHT AS COOLING SETS IN THROUGH THE COLUMN. A WAVE OF LOW PRES
IS FORECAST TO DEVELOP ON THE FRONT WEDNESDAY NIGHT WHICH WILL
HALT THE FORWARD PROGRESS OF THE FRONT. THEREFORE, THE DOWNEAST
REGION WILL HANG ON TO SOME SHOWERS INTO EARLY THURSDAY AFTERNOON.
THE FRONT IS EXPECTED TO CLEAR THE COAST BY LATE IN THE DAY
W/COOLER AND DRIER AIR WORKING DOWN INTO THE REGION. AFTERNOON
HIGHS ON THURSDAY ARE FORECAST TO BE IN THE LOW AND MID 70S.
AN UPPER LEVEL TROF IS EXPECTED TO SLOWLY SWING ACROSS THE REGION
FRIDAY INTO SATURDAY. THIS FEATURE WILL ALLOW FOR CLOUDS TO
DEVELOP BOTH DAYS W/THE RISK OF A SHOWER AS TEMPERATURES ALOFT
WILL BE COOL. DAYTIME TEMPERATURES ARE FORECAST TO BE IN THE 70S
RIGHT INTO THE WEEKEND.
&&
.AVIATION /13Z MONDAY THROUGH FRIDAY/...
NEAR TERM: EXPECT VFR CONDITIONS TODAY AND TONIGHT.
SHORT TERM: VFR FOR TUESDAY INTO EARLY WEDNESDAY W/THE EXCEPTION
OF KBGR AND KBHB AS MVFR/IFR CONDITIONS COULD DEVELOP W/A
SOUTHERLY FLOW. WEDNESDAY COULD BE AN ACTIVE DAY W/THE POTENTIAL
FOR STRONG TSTMS AND LLWS. MVFR AND BRIEF IFR CONDITIONS POSSIBLY
IN THE AFTERNOON INTO THE EVENING. MVFR AND PERHAPS IFR FOR KBGR
AND KBHB FOR WEDNESDAY NIGHT INTO EARLY THURSDAY WHILE THE
NORTHERN TERMINALS SHOULD SEE VFR.
&&
.MARINE...
NEAR TERM: FOR SUSTAINED WINDS HAVE USED THE NAM12. FOR WAVES:
WITH LIGHT WINDS EXPECT PRIMARY WAVE SYSTEM TO BE LONG PERIOD
SOUTHEASTERLY SWELL AROUND 2 FEET/8 SECONDS WHICH IS EXPECTED TO
PERSIST THROUGH TONIGHT.
SHORT TERM: NO HEADLINES ANTICIPATED. A SOUTHEAST SWELL WILL
CONTINUE INTO TUESDAY W/WAVE HEIGHTS OF 2 TO 4 FT AWAY FROM THE
INTRA-COASTAL ZONES INTO WEDNESDAY. SEAS WILL INCREASE ON
WEDNESDAY INTO THURSDAY HITTING 4-5 FT AND ONCE AGAIN AWAY FROM
THE INTRA-COASTAL ZONE. SSW WINDS WILL PICK UP LATER IN THE DAY ON
TUESDAY AND THERE IS POTENTIAL FOR GUSTS TO 20 KTS ON WEDNESDAY
AHEAD OF THE COLD FRONT. SHOWER AND TSTMS ARE POSSIBLE ON
WEDNESDAY AFTERNOON INTO THE EVENING.
&&
.CAR WATCHES/WARNINGS/ADVISORIES...
ME...NONE.
MARINE...NONE.
&&
$$
NEAR TERM...VJN
SHORT TERM...HEWITT
LONG TERM...HEWITT
AVIATION...VJN/HEWITT
MARINE...VJN/HEWITT
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
111 PM EDT MON JUL 21 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 535 AM EDT MON JUL 21 2014
WATER VAPOR IMAGERY AND RUC ANALYSIS SHOW A RIDGE EXTENDING FROM NRN
MEXICO INTO THE WCNTRL PLAINS. A SHORTWAVE WAS MOVING ACROSS NRN
MANITOBA. ASSOCIATED SFC LOW WAS OVER NE MANITOBA WITH TRAILING COLD
FRONT EXTENDING THRU THE WRN PORTION OF NRN ONTARIO AND THEN SW INTO
NW MN AND ND. WITH STRONGER 850MB FLOW IN RESPONSE TO SHORTWAVE
CONFINED MOSTLY TO NRN ONTARIO...SHRA/TSRA HAVE BEEN OCCURRING
MAINLY IN NRN ONTARIO OVERNIGHT WITH SRN END OF CONVECTION AT TIMES
ACROSS THE BORDER IN FAR NRN MN. RECENT RADAR IMAGERY SHOWS A FEW
SHRA NOW DEVELOPING OVER LAKE SUPERIOR BTWN THE KEWEENAW AND ISLE
ROYALE. WELL OUT TO THE W...A SHORTWAVE WAS LIFTING OUT OF THE GREAT
BASIN. THIS FEATURE WILL TRIGGER SVR STORMS THIS AFTN OVER ND WITH
STORMS EVOLVING INTO AN MCS THAT WILL AFFECT THE UPPER LAKES LATE
TONIGHT/TUE.
AS TAIL END OF STRONGER 850MB FLOW SHIFTS E ACROSS LAKE SUPERIOR
THIS MORNING/EARLY AFTN...MAY SEE ISOLD SHRA/TSTMS SPREAD ACROSS
PORTIONS OF NW AND NCNTRL UPPER MI. RECENT SHRA DEVELOPMENT BTWN THE
KEWEENAW AND ISLE ROYALE PROVIDES SOME CONFIDENCE FOR THE POTENTIAL
OF ISOLD CONVECTION FARTHER E AS THE MORNING PROGRESSES. OVERNIGHT
HIGH RES RAPID REFRESH MODEL RUNS HAVE BEEN INSISTENT ON GREATER
COVERAGE OF CONVECTIVE DEVELOPMENT FARTHER S INTO UPPER MI THIS
MORNING. SEEMS OVERDONE...BUT WILL BE SOMETHING TO MONITOR. AS WIND
FIELDS WEAKEN THIS AFTN...LAKE BREEZE MAY SLIP ONSHORE OVER
PORTIONS OF NCNTL UPPER MI. IF SO...NOT OUT OF THE QUESTION THAT A
AN ISOLD TSTM OR TWO COULD DEVELOP ALONG THE BOUNDARY WITHIN
MOIST/UNSTABLE ENVIRONMENT. OTHERWISE...EXPECT PARTLY TO MOSTLY
SUNNY SKIES TODAY ALONG WITH UNCOMFORTABLY HUMID CONDITIONS AS SFC
DWPTS RISE WELL INTO THE 60S...TO AROUND 70F LOCALLY. MIXING TO
AROUND 850MB OR SO ON FCST SOUNDINGS YIELDS MAX TEMPS GENERALLY IN
THE MID TO UPPER 80S. IT WILL BE LOCALLY WARMER WHERE SOUTHERLY
WINDS DOWNSLOPE...AND ONCE AGAIN...IT WILL BE COOLER NEAR LAKE
MICHIGAN...ESPECIALLY E OF KESC.
TONIGHT...ATTENTION TURNS TO SVR STORMS DEVELOPING IN ND THAT WILL
GROW UPSCALE INTO AN MCS IN RESPONSE TO SHORTWAVE MOVING OUT OF THE
ROCKIES AND ACROSS THE NRN PLAINS TOWARD THE UPPER LAKES. MODELS ARE
IN GOOD AGREEMENT ON DEVELOPING CONVECTION OVER ND THIS AFTN.
HOWEVER...AS TIME PROGRESSES...MODELS DIVERGE ON THE EVOLUTION OF
STORMS AND LIKELY MCS TONIGHT INTO TUE MORNING. GIVEN TRACK OF
SHORTWAVE AND POOL OF ELAVATED INSTABILITY ACROSS MN/WI AVBL FOR
STORMS TO TAKE ADVANTAGE OF OVERNIGHT...BELIEVE THE NCEP ARW/NMM AND
NSSL WRF OFFER THE MOST VIABLE SOLUTIONS OF WHAT WILL TRANSPIRE.
THOSE MODELS SHOW TSTMS SPREADING INTO FAR WRN UPPER MI AFT 06Z AND
REACHING CNTRL UPPER MI BY 12Z. WHILE OVERNIGHT TIMING SUGGESTS
STORMS WILL BE WEAKENING AS THEY ARRIVE...DEGREE OF INSTABILITY AVBL
FOR INFLOW MAY STILL SUPPORT SOME SVR THREAT AT LEAST INTO FAR WRN
UPPER MI.
.LONG TERM...(TUESDAY THROUGH SUNDAY)
ISSUED AT 748 AM EDT MON JUL 21 2014
MAIN FOCUS IS ON TUESDAY AS MCS ACTIVITY SHOULD BE MOVING ACROSS THE
CWA. DEVELOPMENT OF A FORWARD PROPAGATING MCS OVER ND MON EVENING
LOOKS LIKELY TO OCCUR...WHICH WOULD BRING THE REMNANTS OF THE MCS
INTO THE CWA MON NIGHT /SEE SHORT TERM DISCUSSION/. THE REMNANTS OF
THE MCS SHOULD THEN MOVE ACROSS THE CWA DURING THE DAY TUE...WITH
THE CURRENT FAVORED TRACK OF THE BEST PRECIP CHANCES OVER LAKE
SUPERIOR/NRN UPPER MI. SO MUCH OF THE PRECIP AND STORM INTENSITY
DURING THE DAY TUE WILL BE DEPENDENT ON MANY OTHER FACTORS...SO
CONFIDENCE IN EXACT DETAILS IS LIMITED. HOWEVER...THINK THAT THE
THREAT FOR SEVERE WEATHER IS LOW GIVEN THAT MORNING INSTABILITY
SHOULD BE AROUND 1000J/KG /HIGHEST OVER THE W NEAR IWD/. AS THE
CONVECTION MOVES E INTO THE AFTERNOON IT WILL ENCOUNTER MORE STABLE
CONDITIONS...SO SEVERE WEATHER IS EVEN LESS LIKELY. A WAKE LOW IS
QUITE POSSIBLE BEHIND THE CONVECTION...WHICH WOULD LEAD TO GUSTY
WINDS...ESPECIALLY OVER LAKE SUPERIOR. WOULD THINK THAT THE THREAT
FOR SIGNIFICANT SEICHE ACTIVITY ON LAKE SUPERIOR IS PRETTY HIGH. MAY
SEE ANOTHER WAVE OF CONVECTION TRYING TO MOVE THROUGH BEHIND THE
INITIAL CONVECTION...BUT THINK THAT THERE WILL NOT BE AS MUCH
INSTABILITY TO WORK WITH DUE TO THE EARLIER CONVECTION.
PRECIP SHOULD BE SE OF THE CWA BY 06Z WED...AND DRY AND COOLER
WEATHER IS EXPECTED THROUGH FRI AS A SFC HIGH MOVES THROUGH THE
REGION. PRECIP CHANCES WILL RETURN OVER THE WEEKEND AS A MORE
UNSETTLED PATTERN SETTLES OVER THE REGION.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON)
ISSUED AT 110 PM EDT MON JUL 21 2014
VFR CONDITIONS WILL PREVAIL AT KIWD/KCMX/KSAW INTO THE OVERNIGHT
HOURS. SHRA/TSTMS DEVELOPING OVER THE NRN PLAINS THIS AFTN/EVENING
WILL MOVE E. THE STORMS SHOULD HOLD TOGETHER AND REACH WRN UPPER MI
LATE TONIGHT...AFFECTING KIWD/KCMX AROUND 09Z OR LATER. MVFR
CONDITIONS SHOULD ACCOMPANY THE PCPN WITH POTENTIAL FOR IFR.
CONFIDENCE WITH STORMS AND WIND DIRECTIONS IS LOW AFTER 09Z AT ALL
SITES AS THE STORMS WILL MANUFACTURE THEIR OWN WEATHER AND MODELS
WILL NOT BE ABLE TO HANDLE THIS.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 535 AM EDT MON JUL 21 2014
SOUTHERLY WINDS WILL CONTINUE OVER MOST OF LAKE SUPERIOR
TODAY/TONIGHT. WHILE S WINDS WILL BE MOSTLY UNDER 20KT...STRONGER
WINDS/GUSTS INTO THE 20-30KT RANGE WILL LIKELY OCCUR AT THE HIGHER
OBS PLATFORMS...MAINLY THIS MORNING AND MAINLY OVER THE E HALF OF
LAKE SUPERIOR. ON TUE...A LOW PRES SYSTEM WILL PASS ACROSS THE UPPER
LAKES...BRINGING A WIND SHIFT TO THE N. AGAIN...THE STRONGER WINDS
OF 15-25KT WILL LIKELY OCCUR OVER ERN LAKE SUPERIOR. IN ADDITION...
DEPENDING ON STRENGTH/COVERAGE AND EVOLUTION OF TSTMS MOVING ACROSS
LAKE SUPERIOR TONIGHT/TUE AHEAD OF LOW...THERE MAY BE A PERIOD OF
STRONG WINDS ACROSS MUCH OF THE LAKE FOR A TIME LATE TONIGHT AND
TUE. HIGH PRES WILL SETTLE INTO THE GREAT LAKES LATE WED THRU
FRI...PROVIDING A PERIOD OF LIGHT WINDS.
ON A FINAL NOTE...FOG MAY EXPAND ACROSS LAKE SUPERIOR TODAY THRU
TUE...ESPECIALLY ONCE PCPN OCCURS.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...ROLFSON
LONG TERM...TITUS
AVIATION...07
MARINE...ROLFSON
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
749 AM EDT MON JUL 21 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 535 AM EDT MON JUL 21 2014
WATER VAPOR IMAGERY AND RUC ANALYSIS SHOW A RIDGE EXTENDING FROM NRN
MEXICO INTO THE WCNTRL PLAINS. A SHORTWAVE WAS MOVING ACROSS NRN
MANITOBA. ASSOCIATED SFC LOW WAS OVER NE MANITOBA WITH TRAILING COLD
FRONT EXTENDING THRU THE WRN PORTION OF NRN ONTARIO AND THEN SW INTO
NW MN AND ND. WITH STRONGER 850MB FLOW IN RESPONSE TO SHORTWAVE
CONFINED MOSTLY TO NRN ONTARIO...SHRA/TSRA HAVE BEEN OCCURRING
MAINLY IN NRN ONTARIO OVERNIGHT WITH SRN END OF CONVECTION AT TIMES
ACROSS THE BORDER IN FAR NRN MN. RECENT RADAR IMAGERY SHOWS A FEW
SHRA NOW DEVELOPING OVER LAKE SUPERIOR BTWN THE KEWEENAW AND ISLE
ROYALE. WELL OUT TO THE W...A SHORTWAVE WAS LIFTING OUT OF THE GREAT
BASIN. THIS FEATURE WILL TRIGGER SVR STORMS THIS AFTN OVER ND WITH
STORMS EVOLVING INTO AN MCS THAT WILL AFFECT THE UPPER LAKES LATE
TONIGHT/TUE.
AS TAIL END OF STRONGER 850MB FLOW SHIFTS E ACROSS LAKE SUPERIOR
THIS MORNING/EARLY AFTN...MAY SEE ISOLD SHRA/TSTMS SPREAD ACROSS
PORTIONS OF NW AND NCNTRL UPPER MI. RECENT SHRA DEVELOPMENT BTWN THE
KEWEENAW AND ISLE ROYALE PROVIDES SOME CONFIDENCE FOR THE POTENTIAL
OF ISOLD CONVECTION FARTHER E AS THE MORNING PROGRESSES. OVERNIGHT
HIGH RES RAPID REFRESH MODEL RUNS HAVE BEEN INSISTENT ON GREATER
COVERAGE OF CONVECTIVE DEVELOPMENT FARTHER S INTO UPPER MI THIS
MORNING. SEEMS OVERDONE...BUT WILL BE SOMETHING TO MONITOR. AS WIND
FIELDS WEAKEN THIS AFTN...LAKE BREEZE MAY SLIP ONSHORE OVER
PORTIONS OF NCNTL UPPER MI. IF SO...NOT OUT OF THE QUESTION THAT A
AN ISOLD TSTM OR TWO COULD DEVELOP ALONG THE BOUNDARY WITHIN
MOIST/UNSTABLE ENVIRONMENT. OTHERWISE...EXPECT PARTLY TO MOSTLY
SUNNY SKIES TODAY ALONG WITH UNCOMFORTABLY HUMID CONDITIONS AS SFC
DWPTS RISE WELL INTO THE 60S...TO AROUND 70F LOCALLY. MIXING TO
AROUND 850MB OR SO ON FCST SOUNDINGS YIELDS MAX TEMPS GENERALLY IN
THE MID TO UPPER 80S. IT WILL BE LOCALLY WARMER WHERE SOUTHERLY
WINDS DOWNSLOPE...AND ONCE AGAIN...IT WILL BE COOLER NEAR LAKE
MICHIGAN...ESPECIALLY E OF KESC.
TONIGHT...ATTENTION TURNS TO SVR STORMS DEVELOPING IN ND THAT WILL
GROW UPSCALE INTO AN MCS IN RESPONSE TO SHORTWAVE MOVING OUT OF THE
ROCKIES AND ACROSS THE NRN PLAINS TOWARD THE UPPER LAKES. MODELS ARE
IN GOOD AGREEMENT ON DEVELOPING CONVECTION OVER ND THIS AFTN.
HOWEVER...AS TIME PROGRESSES...MODELS DIVERGE ON THE EVOLUTION OF
STORMS AND LIKELY MCS TONIGHT INTO TUE MORNING. GIVEN TRACK OF
SHORTWAVE AND POOL OF ELAVATED INSTABILITY ACROSS MN/WI AVBL FOR
STORMS TO TAKE ADVANTAGE OF OVERNIGHT...BELIEVE THE NCEP ARW/NMM AND
NSSL WRF OFFER THE MOST VIABLE SOLUTIONS OF WHAT WILL TRANSPIRE.
THOSE MODELS SHOW TSTMS SPREADING INTO FAR WRN UPPER MI AFT 06Z AND
REACHING CNTRL UPPER MI BY 12Z. WHILE OVERNIGHT TIMING SUGGESTS
STORMS WILL BE WEAKENING AS THEY ARRIVE...DEGREE OF INSTABILITY AVBL
FOR INFLOW MAY STILL SUPPORT SOME SVR THREAT AT LEAST INTO FAR WRN
UPPER MI.
.LONG TERM...(TUESDAY THROUGH SUNDAY)
ISSUED AT 748 AM EDT MON JUL 21 2014
MAIN FOCUS IS ON TUESDAY AS MCS ACTIVITY SHOULD BE MOVING ACROSS THE
CWA. DEVELOPMENT OF A FORWARD PROPAGATING MCS OVER ND MON EVENING
LOOKS LIKELY TO OCCUR...WHICH WOULD BRING THE REMNANTS OF THE MCS
INTO THE CWA MON NIGHT /SEE SHORT TERM DISCUSSION/. THE REMNANTS OF
THE MCS SHOULD THEN MOVE ACROSS THE CWA DURING THE DAY TUE...WITH
THE CURRENT FAVORED TRACK OF THE BEST PRECIP CHANCES OVER LAKE
SUPERIOR/NRN UPPER MI. SO MUCH OF THE PRECIP AND STORM INTENSITY
DURING THE DAY TUE WILL BE DEPENDENT ON MANY OTHER FACTORS...SO
CONFIDENCE IN EXACT DETAILS IS LIMITED. HOWEVER...THINK THAT THE
THREAT FOR SEVERE WEATHER IS LOW GIVEN THAT MORNING INSTABILITY
SHOULD BE AROUND 1000J/KG /HIGHEST OVER THE W NEAR IWD/. AS THE
CONVECTION MOVES E INTO THE AFTERNOON IT WILL ENCOUNTER MORE STABLE
CONDITIONS...SO SEVERE WEATHER IS EVEN LESS LIKELY. A WAKE LOW IS
QUITE POSSIBLE BEHIND THE CONVECTION...WHICH WOULD LEAD TO GUSTY
WINDS...ESPECIALLY OVER LAKE SUPERIOR. WOULD THINK THAT THE THREAT
FOR SIGNIFICANT SEICHE ACTIVITY ON LAKE SUPERIOR IS PRETTY HIGH. MAY
SEE ANOTHER WAVE OF CONVECTION TRYING TO MOVE THROUGH BEHIND THE
INITIAL CONVECTION...BUT THINK THAT THERE WILL NOT BE AS MUCH
INSTABILITY TO WORK WITH DUE TO THE EARLIER CONVECTION.
PRECIP SHOULD BE SE OF THE CWA BY 06Z WED...AND DRY AND COOLER
WEATHER IS EXPECTED THROUGH FRI AS A SFC HIGH MOVES THROUGH THE
REGION. PRECIP CHANCES WILL RETURN OVER THE WEEKEND AS A MORE
UNSETTLED PATTERN SETTLES OVER THE REGION.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z TUESDAY MORNING)
ISSUED AT 748 AM EDT MON JUL 21 2014
VFR CONDITIONS WILL PREVAIL AT KIWD/KCMX/KSAW INTO THE EVENING HRS.
SHRA/TSTMS DEVELOPING OVER THE NRN PLAINS THIS AFTN/EVENING WILL
MOVE E. THE STORMS SHOULD HOLD TOGETHER AND REACH WRN UPPER MI LATE
TONIGHT...AFFECTING KIWD/KCMX AROUND 09Z OR LATER. MVFR CONDITIONS
SHOULD ACCOMPANY THE PCPN WITH POTENTIAL FOR IFR.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 535 AM EDT MON JUL 21 2014
SOUTHERLY WINDS WILL CONTINUE OVER MOST OF LAKE SUPERIOR
TODAY/TONIGHT. WHILE S WINDS WILL BE MOSTLY UNDER 20KT...STRONGER
WINDS/GUSTS INTO THE 20-30KT RANGE WILL LIKELY OCCUR AT THE HIGHER
OBS PLATFORMS...MAINLY THIS MORNING AND MAINLY OVER THE E HALF OF
LAKE SUPERIOR. ON TUE...A LOW PRES SYSTEM WILL PASS ACROSS THE UPPER
LAKES...BRINGING A WIND SHIFT TO THE N. AGAIN...THE STRONGER WINDS
OF 15-25KT WILL LIKELY OCCUR OVER ERN LAKE SUPERIOR. IN ADDITION...
DEPENDING ON STRENGTH/COVERAGE AND EVOLUTION OF TSTMS MOVING ACROSS
LAKE SUPERIOR TONIGHT/TUE AHEAD OF LOW...THERE MAY BE A PERIOD OF
STRONG WINDS ACROSS MUCH OF THE LAKE FOR A TIME LATE TONIGHT AND
TUE. HIGH PRES WILL SETTLE INTO THE GREAT LAKES LATE WED THRU
FRI...PROVIDING A PERIOD OF LIGHT WINDS.
ON A FINAL NOTE...FOG MAY EXPAND ACROSS LAKE SUPERIOR TODAY THRU
TUE...ESPECIALLY ONCE PCPN OCCURS.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...ROLFSON
LONG TERM...TITUS
AVIATION...ROLFSON
MARINE...ROLFSON
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
536 AM EDT MON JUL 21 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 535 AM EDT MON JUL 21 2014
WATER VAPOR IMAGERY AND RUC ANALYSIS SHOW A RIDGE EXTENDING FROM NRN
MEXICO INTO THE WCNTRL PLAINS. A SHORTWAVE WAS MOVING ACROSS NRN
MANITOBA. ASSOCIATED SFC LOW WAS OVER NE MANITOBA WITH TRAILING COLD
FRONT EXTENDING THRU THE WRN PORTION OF NRN ONTARIO AND THEN SW INTO
NW MN AND ND. WITH STRONGER 850MB FLOW IN RESPONSE TO SHORTWAVE
CONFINED MOSTLY TO NRN ONTARIO...SHRA/TSRA HAVE BEEN OCCURRING
MAINLY IN NRN ONTARIO OVERNIGHT WITH SRN END OF CONVECTION AT TIMES
ACROSS THE BORDER IN FAR NRN MN. RECENT RADAR IMAGERY SHOWS A FEW
SHRA NOW DEVELOPING OVER LAKE SUPERIOR BTWN THE KEWEENAW AND ISLE
ROYALE. WELL OUT TO THE W...A SHORTWAVE WAS LIFTING OUT OF THE GREAT
BASIN. THIS FEATURE WILL TRIGGER SVR STORMS THIS AFTN OVER ND WITH
STORMS EVOLVING INTO AN MCS THAT WILL AFFECT THE UPPER LAKES LATE
TONIGHT/TUE.
AS TAIL END OF STRONGER 850MB FLOW SHIFTS E ACROSS LAKE SUPERIOR
THIS MORNING/EARLY AFTN...MAY SEE ISOLD SHRA/TSTMS SPREAD ACROSS
PORTIONS OF NW AND NCNTRL UPPER MI. RECENT SHRA DEVELOPMENT BTWN THE
KEWEENAW AND ISLE ROYALE PROVIDES SOME CONFIDENCE FOR THE POTENTIAL
OF ISOLD CONVECTION FARTHER E AS THE MORNING PROGRESSES. OVERNIGHT
HIGH RES RAPID REFRESH MODEL RUNS HAVE BEEN INSISTENT ON GREATER
COVERAGE OF CONVECTIVE DEVELOPMENT FARTHER S INTO UPPER MI THIS
MORNING. SEEMS OVERDONE...BUT WILL BE SOMETHING TO MONITOR. AS WIND
FIELDS WEAKEN THIS AFTN...LAKE BREEZE MAY SLIP ONSHORE OVER
PORTIONS OF NCNTL UPPER MI. IF SO...NOT OUT OF THE QUESTION THAT A
AN ISOLD TSTM OR TWO COULD DEVELOP ALONG THE BOUNDARY WITHIN
MOIST/UNSTABLE ENVIRONMENT. OTHERWISE...EXPECT PARTLY TO MOSTLY
SUNNY SKIES TODAY ALONG WITH UNCOMFORTABLY HUMID CONDITIONS AS SFC
DWPTS RISE WELL INTO THE 60S...TO AROUND 70F LOCALLY. MIXING TO
AROUND 850MB OR SO ON FCST SOUNDINGS YIELDS MAX TEMPS GENERALLY IN
THE MID TO UPPER 80S. IT WILL BE LOCALLY WARMER WHERE SOUTHERLY
WINDS DOWNSLOPE...AND ONCE AGAIN...IT WILL BE COOLER NEAR LAKE
MICHIGAN...ESPECIALLY E OF KESC.
TONIGHT...ATTENTION TURNS TO SVR STORMS DEVELOPING IN ND THAT WILL
GROW UPSCALE INTO AN MCS IN RESPONSE TO SHORTWAVE MOVING OUT OF THE
ROCKIES AND ACROSS THE NRN PLAINS TOWARD THE UPPER LAKES. MODELS ARE
IN GOOD AGREEMENT ON DEVELOPING CONVECTION OVER ND THIS AFTN.
HOWEVER...AS TIME PROGRESSES...MODELS DIVERGE ON THE EVOLUTION OF
STORMS AND LIKELY MCS TONIGHT INTO TUE MORNING. GIVEN TRACK OF
SHORTWAVE AND POOL OF ELAVATED INSTABILITY ACROSS MN/WI AVBL FOR
STORMS TO TAKE ADVANTAGE OF OVERNIGHT...BELIEVE THE NCEP ARW/NMM AND
NSSL WRF OFFER THE MOST VIABLE SOLUTIONS OF WHAT WILL TRANSPIRE.
THOSE MODELS SHOW TSTMS SPREADING INTO FAR WRN UPPER MI AFT 06Z AND
REACHING CNTRL UPPER MI BY 12Z. WHILE OVERNIGHT TIMING SUGGESTS
STORMS WILL BE WEAKENING AS THEY ARRIVE...DEGREE OF INSTABILITY AVBL
FOR INFLOW MAY STILL SUPPORT SOME SVR THREAT AT LEAST INTO FAR WRN
UPPER MI.
.LONG TERM...(MONDAY NIGHT THROUGH SUNDAY)
ISSUED AT 442 PM EDT SUN JUL 20 2014
MONDAY NIGHT INTO TUESDAY UPPER MI WILL BE SANDWICHED IN A WEAK
TROUGH BETWEEN TWO SURFACE HIGH PRESSURE CENTERS...ONE OVER THE MID
ATLANTIC AND THE OTHER OVER THE CANADIAN PRAIRIES. ALOFT...STRONG
HIGH PRESSURE IS ANCHORED OVER NEW MEXICO AND THE MID ATLANTIC...AND
LOW PRESSURE IS SITUATED OVER HUDSON BAY. AS A RESULT...500MB FLOW
OVER THE NORTHERN PLAINS AND UPPER MI IS SOMEWHAT ZONAL. A POTENT
SHORTWAVE WILL KICK OFF CONVECTION IN THE NORTHERN PLAINS BY LATE
MONDAY AFTERNOON. THIS CONVECTIVE COMPLEX WILL BE THE MAIN FEATURE
OF INTEREST FOR THE LONG TERM FORECAST.
HAVE LIKELY TO CATEGORICAL POPS THROUGH THE CWA MONDAY NIGHT INTO
TUESDAY. MUCAPE VALUES SHOW EXTREME INSTABILITY BY U.P. STANDARDS
ACROSS THE WESTERN U.P. MONDAY EVENING /00Z TUE. MUCAPE VALUES ARE
FORECAST TO BE UPWARDS OF 3000 J/KG...AND MORE LIKE 1000 J/KG IN THE
EAST. THIS IS CONDITIONAL THOUGH...GIVEN THE ENVIRONMENT WILL BE
LARGELY CAPPED WITH THE RIDGE IN PLACE. HOWEVER...ISENTROPIC ASCENT
ON THE 315K SFC AHEAD OF THE DEVELOPING SURFACE LOW...AND A 25 TO 35
KNOT LL JET OVER SOUTHERN MN/WESTERN WI/IOWA WILL SUPPORT AN
ENVIRONMENT FAVORABLE FOR SUSTAINING ANY INCOMING MCS AND FOR
DEVELOPING ELEVATED CONVECTION AFTER 00Z TUE. 0-6 KM/1-6KM SHEAR IS
FAVORABLE FOR MCS SUSTAINABILITY/TSTORMS DEVELOPMENT AS
WELL...AROUND 25-40 KNOTS THROUGH MUCH OF TUESDAY. WITH A SHALLOW
STABLE LAYER AT THE SURFACE...THINKING SOME SEVERE LEVEL WIND GUSTS
AND HAIL ARE A SIGNIFICANT POSSIBILITY. THE BEST CHANCES WILL BE
OVERNIGHT MONDAY AND THROUGH EARLY TUESDAY MORNING ACROSS THE WEST
AND CENTRAL. AS FAR AS TIMING GOES...EXPECT SHOWERS/STORMS TO MOVE
IN/DEVELOP LATE MONDAY EVENING /3Z/ OUT WEST...AND CONTINUE TO MOVE
EASTWARD THROUGH TUESDAY...THOUGH SEVERE POTENTIAL DIMINISHES AS
THINGS PROGRESS EASTWARD. GENERALLY THE BETTER INSTABILITY
DIMINISHES AND BECOMES LARGELY CONFINED TO THE WEST/CENTRAL U.P./WI
BORDER THROUGHOUT THE DAY...AND THE UPPER LEVEL SUPPORT DIMINISHES
AS THE LOW EXITS THE AREA.
LARGE SCALE RIDGING EXTENDING FROM THE HIGH PRESSURE CENTERED OVER
NEW MEXICO WILL SHIFT SLIGHTLY EASTWARD INTO THE MIDWEST...ALLOWING
SURFACE HIGH PRESSURE TO INFILTRATE UPPER MICHIGAN FOR WEDNESDAY
AFTERNOON AND THURSDAY. THIS WILL BRING A COOL DOWN AND DRIER
CONDITIONS TO THE REGION...ESPECIALLY WEDNESDAY WITH NORTHERLY WINDS
OFF LAKE SUPERIOR. 850MB TEMPS WILL BE AROUND 7-10C...SO EXPECT HIGH
TEMPERATURES IN THE 60S AND 70S.
AN UPPER LEVEL LOW WILL MOVE FROM ALBERTA INTO ONTARIO OVER THE
WEEKEND...BRINGING UNSETTLED WEATHER BACK TO THE GREAT LAKES THIS
WEEKEND AND FOR THE START OF NEXT WEEK. HAVE KEPT CHANCE
SHOWERS/TSTORMS FOR NOW. TEMPS LOOK SEASONABLE...WITH HIGHS IN THE
UPPER 60S AND 70S.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT)
ISSUED AT 137 AM EDT MON JUL 21 2014
VFR CONDITIONS ARE EXPECTED TO PREVAIL THROUGH THE FCST PERIOD AT
KIWD/KCMX/KSAW. THE REMNANTS OF SHRA/TSRA IN NRN MN MAY REACH NW
UPPER MI LATE OVERNIGHT AT CMX. SINCE THE PROBABILITY/CONFIDENCE IS
LOW...IT WAS NOT MENTIONED IN THE TAF AT THIS TIME. ADDITIONAL AREAS
OF TSRA ARE EXPECTED TO DEVELOP THIS EVENING TO THE WEST OF UPPER MI AND
WILL MOVE TOWARD THE AREA...BUT REMAIN WEST OF IWD/CMX THROUGH
06Z/TUE.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 535 AM EDT MON JUL 21 2014
SOUTHERLY WINDS WILL CONTINUE OVER MOST OF LAKE SUPERIOR
TODAY/TONIGHT. WHILE S WINDS WILL BE MOSTLY UNDER 20KT...STRONGER
WINDS/GUSTS INTO THE 20-30KT RANGE WILL LIKELY OCCUR AT THE HIGHER
OBS PLATFORMS...MAINLY THIS MORNING AND MAINLY OVER THE E HALF OF
LAKE SUPERIOR. ON TUE...A LOW PRES SYSTEM WILL PASS ACROSS THE UPPER
LAKES...BRINGING A WIND SHIFT TO THE N. AGAIN...THE STRONGER WINDS
OF 15-25KT WILL LIKELY OCCUR OVER ERN LAKE SUPERIOR. IN ADDITION...
DEPENDING ON STRENGTH/COVERAGE AND EVOLUTION OF TSTMS MOVING ACROSS
LAKE SUPERIOR TONIGHT/TUE AHEAD OF LOW...THERE MAY BE A PERIOD OF
STRONG WINDS ACROSS MUCH OF THE LAKE FOR A TIME LATE TONIGHT AND
TUE. HIGH PRES WILL SETTLE INTO THE GREAT LAKES LATE WED THRU
FRI...PROVIDING A PERIOD OF LIGHT WINDS.
ON A FINAL NOTE...FOG MAY EXPAND ACROSS LAKE SUPERIOR TODAY THRU
TUE...ESPECIALLY ONCE PCPN OCCURS.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...ROLFSON
LONG TERM...MCD
AVIATION...JLB
MARINE...ROLFSON
AREA FORECAST DISCUSSION...UPDATED
NWS JACKSON MS
947 AM CDT MON JUL 21 2014
.UPDATE...
WATER VAPOR ANALYSIS INDICATES UPPER LEVEL LOW BEGINNING TO CUT OFF
OVER NRN AL WITH S/WV MOVING THROUGH ERN MS. A STATIONARY SURFACE
BOUNDARY IS DRAPED ACROSS THE COAST THROUGH SE MS INTO CENTRAL AL.
EXPECT SOME SHOWERS/STORMS POSSIBLE THIS AFTERNOON JUST TO THE N/NW
OF THE BOUNDARY DUE TO S/WV LIFT AND LOW LEVEL CONVERGENCE. HRRR
INDICATES MOST WILL BE IN E/SE MS. LOWERED HIGHS SLIGHTLY ACROSS THE
REGION DUE TEMPS ALOFT IN 12Z KJAN SOUNDING/MODEL SOUNDINGS
SUPPORTING SLIGHTLY COOLER TEMPS AND LAV HOURLY TEMPS ARE SUPPORTIVE
OF THIS IDEA. THE LOW LEVEL STRATUS IN CENTRAL/SW MS AND FOG IN SE
MS WILL SLOWLY CLEAR OVER THE NEXT FEW HOURS. OVERALL...ADJUSTED
HOURLY TEMPS/DEWPOINTS/SKY GRIDS TO CURRENT TRENDS.
ALSO...LOOKING AT TUESDAY GUIDANCE EARLIER SEEMED BULLISH ON HIGH
TEMPS AND WITH INCREASING MID-LEVEL CLOUDS/STORMS IN E/SE MS AND
TEMPS ALOFT IN MODEL SOUNDINGS...WENT WITH EURO MOS FOR HIGHS
TUESDAY. THIS WAS AROUND 2-5 DEGREES COOLER AT SOME SITES BUT MAVMOS
SEEMS TO HAVE COME DOWN IN CURRENT RUN. WILL LOOK TO MAKE ANY
FURTHER ADJUSTMENTS IN AFTERNOON PACKAGE. REST OF THE FORECAST IS ON
TRACK. /DC/
&&
.AVIATION...MORNING RESTRICTED CONDITIONS ARE IMPROVING AND LOOK FOR
VFR CONDITIONS TODAY INTO MOST OF THE EVENING PERIOD. THERE COULD BE
AN ISO SHRA ACROSS THE EASTERN SITES. THE FOCUS THEN SHIFTS TO LATER
TONIGHT WHERE MORE PATCH FOG/LOW CEILINGS MAY DEVELOP. IT WITH BE
PATCHY...BUT PERSISTENCE INDICATES IT WILL OCCUR AGAIN. /CME/
&&
.PREV DISCUSSION... /ISSUED 531 AM CDT MON JUL 21 2014/
SHORT TERM...TODAY AND TONIGHT. FOG AND SOME STRATUS REMAIN OVER THE
AREA. RUC SHOWS A SHORTWAVE OVER THE AREA...SIMILAR TO WHAT THE
MODELS WERE SHOWING...WITH THE AXIS EXTENDING BACK INTO LOUISIANA AND
NORTHEAST TEXAS...WHERE MORE CLOUDS WERE FORMING. NOT EXPECTING MUCH
TO HAPPEN TO THE WEST TODAY. DRIER AIR SHOULD PREVAIL THIS
AFTERNOON. IN THE EAST...WITH THE UPPER WAVE...ISOLATED SHOWERS DEVELOPED
EARLY THIS MORNING. THOUGHT THEY WOULD QUICKLY DISSIPATE...BUT THEY
HAVE LINGERED FOR A LITTLE WHILE. ADDED ISOLATED SHOWERS TO THE
FORECAST FOR THE MORNING. GUIDANCE CAME IN WITH SOME SLIGHT CHANCE
POPS IN THE FAR SOUTHEAST...EXPANDED THE AREA AND LEFT ISOLATED
SHOWER/THUNDERSTORMS IN THE FORECAST THROUGH TODAY. THE NAM SHOWS
MORE WIDESPREAD CONVECTION FOR TOMORROW. STUCK WITH THE GFS AND LEFT
THE RAIN CHANCES IN THE EAST AGAIN TOMORROW. EURO AND GFS SHOW THE
UPPER RIDGE MAINTAIN A STRONGHOLD AND KEEPING THE WAVE FROM
RETROGRADING ANY FURTHER. EXPECTING CLOUDS TO SPREAD ACROSS THE AREA
ON TUESDAY. NOT LOOKING FOR ANOTHER RECORD BREAKING DAY...BUT MOST
LOCATIONS ARE UNLIKELY TO CLIMB OUT OF THE 80S AGAIN TODAY. THE UPPER
WAVE/AXIS WILL BE THE FOCUS FOR SHOWERS AND A FEW THUNDERSTORMS AGAIN
TOMORROW. TEMPERATURES SHOULD BE CLOSER TO NORMAL. /07/
LONG TERM...FROM MID TO LATE WEEK...GLOBAL MODELS ARE IN AGREEMENT THAT A
WEAKENING UPPER LEVEL TROUGH OVER THE LOWER MS VALLEY REGION WILL
SUPPORT PRIMARILY DIURNAL SHOWER/THUNDERSTORM ACTIVITY WEDNESDAY.
SHORTWAVE ENERGY DIGGING SOUTH AROUND THE PERIPHERY OF THE INTENSE
SUBTROPICAL RIDGE CENTER LOCATED OVER THE CENTRAL HIGH PLAINS REGION
MAY HELP TO ENHANCE THUNDERSTORM CHANCES WEDNESDAY NIGHT/THURSDAY
INTO FRIDAY. HAVE INCORPORATED A BLEND OF MOS GUIDANCE WHILE
INCREASING POPS SOME WED NIGHT NORTH OF THE I-20 CORRIDOR.
GOING INTO THE WEEKEND...THE INTENSIFYING SUBTROPICAL RIDGE AXIS IS
FORECAST TO EXPAND EASTWARD INTO THE ARKLAMISS WITH H850
TEMPERATURES APPROACHING 22 DEG C OVER THE DELTA REGION. THIS WILL
BE THE BEST CHANCE FOR THE FORECAST AREA TO EXPERIENCE ELEVATED
LEVELS OF HEAT STRESS IN WHAT HAS BEEN A RELATIVELY COOL JULY. GIVEN
THE CONTINUED MOIST SOIL CONDITIONS AND THE HOT DAYTIME BIAS OF THE
GFS MEX MOS...HAVE ADJUSTED FORECAST HIGHS TOWARD THE COOLER ECMWF
MOS. HOWEVER...THE MODEL OUTPUT IS CERTAINLY MORE PRONOUNCED WITH
THE SIGNAL FOR HOT CONDITIONS.
LOOKING AHEAD TO EARLY NEXT WEEK...ANOMALOUS NORTHWEST FLOW MAY HELP
TO SUPPRESS THE RIDGE AND BRING AN ACTIVE WEATHER PATTERN TO THE
ARKLAMISS WITH GREATER THUNDERSTORM CHANCES. /EC/
&&
.PRELIMINARY POINT TEMPS/POPS...
JACKSON 88 68 89 70 / 2 4 13 9
MERIDIAN 89 67 90 70 / 16 8 23 15
VICKSBURG 87 65 90 67 / 2 4 8 9
HATTIESBURG 89 70 92 71 / 19 8 22 16
NATCHEZ 86 66 88 69 / 5 4 8 14
GREENVILLE 87 68 92 71 / 2 4 9 6
GREENWOOD 89 67 91 69 / 2 4 12 7
&&
.JAN WATCHES/WARNINGS/ADVISORIES...
MS...NONE.
LA...NONE.
AR...NONE.
&&
$$
DC/CME/07/EC
AREA FORECAST DISCUSSION
NWS JACKSON MS
531 AM CDT MON JUL 21 2014
.SHORT TERM...TODAY AND TONIGHT. FOG AND SOME STRATUS REMAIN OVER THE
AREA. RUC SHOWS A SHORTWAVE OVER THE AREA...SIMILAR TO WHAT THE
MODELS WERE SHOWING...WITH THE AXIS EXTENDING BACK INTO LOUISIANA AND
NORTHEAST TEXAS...WHERE MORE CLOUDS WERE FORMING. NOT EXPECTING MUCH
TO HAPPEN TO THE WEST TODAY. DRIER AIR SHOULD PREVAIL THIS
AFTERNOON. IN THE EAST...WITH THE UPPER WAVE...ISOLATED SHOWERS DEVELOPED
EARLY THIS MORNING. THOUGHT THEY WOULD QUICKLY DISSIPATE...BUT THEY
HAVE LINGERED FOR A LITTLE WHILE. ADDED ISOLATED SHOWERS TO THE
FORECAST FOR THE MORNING. GUIDANCE CAME IN WITH SOME SLIGHT CHANCE
POPS IN THE FAR SOUTHEAST...EXPANDED THE AREA AND LEFT ISOLATED
SHOWER/THUNDERSTORMS IN THE FORECAST THROUGH TODAY. THE NAM SHOWS
MORE WIDESPREAD CONVECTION FOR TOMORROW. STUCK WITH THE GFS AND LEFT
THE RAIN CHANCES IN THE EAST AGAIN TOMORROW. EURO AND GFS SHOW THE
UPPER RIDGE MAINTAIN A STRONGHOLD AND KEEPING THE WAVE FROM
RETROGRADING ANY FURTHER. EXPECTING CLOUDS TO SPREAD ACROSS THE AREA
ON TUESDAY. NOT LOOKING FOR ANOTHER RECORD BREAKING DAY...BUT MOST
LOCATIONS ARE UNLIKELY TO CLIMB OUT OF THE 80S AGAIN TODAY. THE UPPER
WAVE/AXIS WILL BE THE FOCUS FOR SHOWERS AND A FEW THUNDERSTORMS AGAIN
TOMORROW. TEMPERATURES SHOULD BE CLOSER TO NORMAL.
.LONG TERM...FROM MID TO LATE WEEK...GLOBAL MODELS ARE IN AGREEMENT THAT A
WEAKENING UPPER LEVEL TROUGH OVER THE LOWER MS VALLEY REGION WILL
SUPPORT PRIMARILY DIURNAL SHOWER/THUNDERSTORM ACTIVITY WEDNESDAY.
SHORTWAVE ENERGY DIGGING SOUTH AROUND THE PERIPHERY OF THE INTENSE
SUBTROPICAL RIDGE CENTER LOCATED OVER THE CENTRAL HIGH PLAINS REGION
MAY HELP TO ENHANCE THUNDERSTORM CHANCES WEDNESDAY NIGHT/THURSDAY
INTO FRIDAY. HAVE INCORPORATED A BLEND OF MOS GUIDANCE WHILE
INCREASING POPS SOME WED NIGHT NORTH OF THE I-20 CORRIDOR.
GOING INTO THE WEEKEND...THE INTENSIFYING SUBTROPICAL RIDGE AXIS IS
FORECAST TO EXPAND EASTWARD INTO THE ARKLAMISS WITH H850
TEMPERATURES APPROACHING 22 DEG C OVER THE DELTA REGION. THIS WILL
BE THE BEST CHANCE FOR THE FORECAST AREA TO EXPERIENCE ELEVATED
LEVELS OF HEAT STRESS IN WHAT HAS BEEN A RELATIVELY COOL JULY. GIVEN
THE CONTINUED MOIST SOIL CONDITIONS AND THE HOT DAYTIME BIAS OF THE
GFS MEX MOS...HAVE ADJUSTED FORECAST HIGHS TOWARD THE COOLER ECMWF
MOS. HOWEVER...THE MODEL OUTPUT IS CERTAINLY MORE PRONOUNCED WITH
THE SIGNAL FOR HOT CONDITIONS.
LOOKING AHEAD TO EARLY NEXT WEEK...ANOMALOUS NORTHWEST FLOW MAY HELP
TO SUPPRESS THE RIDGE AND BRING AN ACTIVE WEATHER PATTERN TO THE
ARKLAMISS WITH GREATER THUNDERSTORM CHANCES. /EC/
&&
.AVIATION...MVFR CONDITIONS WILL CONTINUE FOR GLH/GWO DUE TO PATCHY
FOG. LOOKING FOR THE FOG TO LIFT AROUND 9 AM. ISOLATED SHOWERS AND
MAYBE A THUNDERSTORM MAY IMPACT MEI/HBG IN THE AFTERNOON. OTHERWISE
THE VFR CONDITIONS SHOULD PREVAIL FOR THE REMAINDER OF THE DAY. MORE
PATCHY FOG MAY DEVELOP ACROSS THE AREA LATE TONIGHT.
&&
.PRELIMINARY POINT TEMPS/POPS...
JACKSON 89 68 94 70 / 2 4 13 9
MERIDIAN 90 67 93 70 / 16 8 23 15
VICKSBURG 88 65 93 67 / 2 4 8 9
HATTIESBURG 92 70 94 71 / 19 8 22 16
NATCHEZ 87 66 91 69 / 5 4 8 14
GREENVILLE 88 68 93 71 / 2 4 9 6
GREENWOOD 90 67 93 69 / 2 4 12 7
&&
.JAN WATCHES/WARNINGS/ADVISORIES...
MS...NONE.
LA...NONE.
AR...NONE.
&&
$$
07/EC/
AREA FORECAST DISCUSSION...UPDATED AVIATION
NWS ST LOUIS MO
708 PM CDT Tue Jul 22 2014
.SHORT TERM: (Through Late Tonight)
Issued at 330 PM CDT Tue Jul 22 2014
There is a considerable amount of uncertainty in the convective
evolution and coverage tonight. Dew points in the 70s, strong
heating and steep mid level lapse rates are currently contributing
to SBCAPE of 3500-6000 j/kg across the northwest 2/3rds of the CWA
with the highest values across central and north central MO. There
also is a significant cap in place due to warm mid level temperatures.
The big question is when and how much of the cap will be reduced
as the front moves southward out of Iowa and southeast Nebraska
into northern MO this evening. Model solutions including the
convection allowing models are quite varied on QPF and implied
coverage. Recent runs of the HRRR are quite stingy on coverage
with isolated storms at best. I don`t have a great feel for what
is going to occur, but the deterministic models suggest that height
falls/cooling aloft should be sufficient to weaken the cap and
allow for scattered development along front, mainly late this
evening and especially overnight. I have attempted to follow this
trend with the greatest coverage along/east of the MS river. The
severe threat is conditional on development early enough this
evening to realize the big CAPE, and the main threat would appear
to be damaging winds given the warm air aloft.
Glass
.LONG TERM: (Wednesday through Next Tuesday)
Issued at 330 PM CDT Tue Jul 22 2014
The cold front should lie roughly from south central IL to near
St. Louis into southwest MO at 12z and exit the CWA by early
afternoon. There will continue to be a threat of scattered showers
and storms ahead of the advancing front. Temperatures should be
cooler tomorrow with the main thrust of cooling and drying in the
afternoon. Unseasonably deep upper troffing in the eastern U.S.
will keep a large surface high dominating the area Wednesday night
into Friday, with most of this period dominated by lower humidity
and below average temperatures.
Beginning late Thursday night and into Friday the threat of precipitation
will return in association with elevated showers/thunderstorms due to
strong warm advection/moisture transport via a southwesterly LLJ ahead
of the slowly retreating warm front and in association with impulses
aloft dropping southeastward along the eastern periphery of the
upper high. A cold front will then drop through the area Saturday
afternoon-Sunday as a upper trof digs southeastward from the upper
MS valley and into the Great Lakes bringing another threat of
showers and thunderstorms. This upper wave will be part of large
scale amplification of the upper air pattern across NOAM and will
feature another deep trof over the eastern U.S. through the first
part of next week and send out July with another period of below
average temperatures.
Glass
&&
.AVIATION: (For the 00z TAFs through 00z Wednesday Evening)
Issued at 647 PM CDT Tue Jul 22 2014
Focus remains on thunder potential this evening into the overnight
and possible MVFR CIGs Wednesday morning. Storms are expected to
form along a cold front that currently stretches from ern IA into
NW MO then into NE KS. TSTMs are fcst to dvlp later this evng and
push slowly SE. Think storms will eventually dvlp...but not
confident on coverage or any particular cell impacting one of the
terminals. The front is relatively weak and moving slowly...so it
will take most of the night for it to clear the terminals. This
means that storms may take longer to clear a terminal than is
currently indicated. TSTMs are expected to dvlp along the front
again tomorrow aftn/evng...but should be well south of the
terminals by then. There is the potential for some post frontal
high end MVFR stratus/stratocu Wednesday morning. If it
dvlps...should not last long...burning off by mid/late mrng. If
any terminal gets rain this evng or overnight...there is the
potential for fog by morning as the bndry lyr remains quite moist
behind the front...esp if the expected low clouds do not form.
Beyond tomorrow morning...diurnal cu and a N/NNE breeze as high
pressure builds into the region.
Specifics for KSTL:
Possible for TSTMs overnight...but not sure of the coverage. There
is the potential for storms to remain near the terminal later than
indicated based on the slow mvmnt of the front. Models indicate
the potential for high end MVFR clouds towards 12Z...but again not
confident on this scenario. If the terminal did get rain...then
fog might be possible given the moist bndry layer behind the
front...esp if the lower clouds do not form.
2%
&&
.LSX WATCHES/WARNINGS/ADVISORIES:
MO...NONE.
IL...NONE.
&&
$$
WFO LSX
AREA FORECAST DISCUSSION
NWS KANSAS CITY/PLEASANT HILL MO
639 PM CDT Tue Jul 22 2014
.DISCUSSION...
Issued at 333 PM CDT TUE JUL 22 2014
Mid to upper 90s prevailing across much of the region this afternoon
as the warmest airmass of the season continues to grip the area.
Latest 850-mb analysis from the SPC meso site showing the 28C temp
contour directly over the fcst region this afternoon. This combined
with steep low-level lapse rates and dewpoints largely in the lower
to middle 70s has resulted in a very hot and oppressive day across
the area. Current heat advisory for the entire fcst area needs no
adjustments and is set to expire at 7 PM this evening.
In addition to the heat...the other main concern remains focused on
possible severe convection later this evening as main cold front now
found over southwestern IA and eastern NE continues to slowly track
south with time. For what its worth...high-res convection allowing
models struggled mightily with this mornings convection across
our northeastern zones...and very little guidance from these models
appears to be in the offering for activity later this evening as
well. Not surprisingly...overall confidence for tonight/s fcst is
less than desired as some models show developing convection...while
others such as the HRRR continue to backtrack towards a drier and
drier fcst with each successive run. So here/s what we know so far...
Sfc boundary set to arrive towards the IA/MO state line around 00z
this evening. Out ahead of this feature...airmass remains capped with
a significant amount of inhibition thanks that 700-mb temps ranging
in the 12-14C range. Additionally...northerly 925-850-mb winds will
provide little if any low-level convergence into the arriving
frontal boundary as we continue into the evening hrs. Despite
this...quick look at latest water vapor imagery does show an inbound
shortwave trough now seen over south-central NE and north-central
KS. This feature combined with very modest frontal convergence may be
enough to get this going...however concerns for widespread severe
remain marginal as of this writing. Latest SPC day 1 outlook has
trimmed the SLGT risk mention further to the southeast...which is
more in line with where convection may develop as front continues to
drop south. That said...main severe threat with any activity that
forms will likely be strong wind gusts as nearly dry adiabatic lapse
rates will support favorable low-level and boundary layer mixing.
High wet-bulb zero heights (>16 kft) will likely negate the threat
for very large hail until later on when any lingering activity begins
to go elevated with due to loss of daytime heating. Overall concerns
for hail though remain the lowest of the two forms of severe outlined
above however. In general...severe threat this evening looks to be
isolated with the most likely areas to possibly see a rogue storm or
two residing in our northeastern zones where better potential exists
to break the cap thanks to slightly cooler temps aloft. If activity gets
going...severe threat should transition south of the I-70 corridor as
front continues to make progress through the area. As mentioned above
through...a widespread severe event does not look to be in the
offering this evening.
Region should largely reside in a post frontal airmass
tomorrow...with weak dry air advection allowing for cooler and less
humid conditions. In fact...fcst models suggest dewpoints anywhere
between 5-10 degrees cooler than today...which should be a welcomed
relief following today/s oppressive conditions. High temps should
round out in the middle to upper 80s.
Large scale pattern shift expected from Thursday into Friday as southern
Plains ridge retrograde west as northern stream energy traverses the
northern Rockies/Plains. As this occurs...upper flow will become
decidedly more northwesterly which will set the stage for unsettled
conditions heading into the upcoming weekend. Closer to the
surface...fcst models still paint a northward retreating warm front
by late week as return flow reestablishes itself across the Great
Plains in advance of lee side troughing along the Front Range. Several
upper shortwaves embedded in northwest flow will allow for continued
chances for showers and storms through at least Saturday...if not
Sunday. As is the case with convection this time of year...hard to
pin your hat on any one feature of interest as long range models to
include both the ECMWF and GFS normally suffer from convective
feedback issues to some degree. As a result...have maintained Chc
pops through the weekend before high pressure arrives by early next
week following the passage of a cold front on Sunday. Temps early
next week look to fall below normal with highs possibly only reaching
into the lower to middle 80s come Monday and Tuesday.
&&
.AVIATION...(For the 00Z TAFS through 00Z Wednesday Evening)
Issued at 639 PM CDT TUE JUL 22 2014
A modest cold front is settling south through Missouri this evening,
and is currently found between the KSTJ and KMCI terminals in
northwest Missouri. Storms along the front are looking less and less
likely given the lack of cloud development. So, have removed the VCTS
for this evening. Otherwise, winds behind the front will veer around
to the northeast by sunrise Wednesday morning.
&&
.EAX WATCHES/WARNINGS/ADVISORIES...
KS...HEAT ADVISORY until 7 PM CDT this evening FOR KSZ025-057-060-
102>105.
MO...HEAT ADVISORY until 7 PM CDT this evening FOR MOZ001>008-011>017-
020>025-028>033-037>040-043>046-053-054.
&&
$$
DISCUSSION...32
AVIATION...Cutter
AREA FORECAST DISCUSSION
NWS OMAHA/VALLEY NE
1225 PM CDT MON JUL 21 2014
.UPDATE...
ISSUED AT 1225 PM CDT MON JUL 21 2014
ONLY MADE MINOR TWEAKS TO THE FORECAST FOR THIS AFTERNOON. DEWPOINTS
WERE MAINLY IN THE LOWER AND MID 70S...WITH SOME UPPER 70S NOTED
JUST NORTH OF WEAK LOW LEVEL CONVERGENCE ZONE THAT EXTENDED FROM
LOW PRESSURE OVER WESTERN SOUTH DAKOTA INTO WESTERN IOWA.
&&
.SHORT TERM...(TODAY THROUGH WEDNESDAY)
ISSUED AT 335 AM CDT MON JUL 21 2014
SHORT TERM FORECAST CONCERNS WILL BE STRATUS DEVELOPMENT AND IF
ANY ISOLATED TSRA CAN DEVELOP...THEN HEAT HEADLINES FOR TODAY AND
TUESDAY.
THE 00Z OAX SOUNDING WAS UNSTABLE...BUT CAPPED WITH 1.54 INCHES OF
PWAT. THE MID TROPOSPHERIC RIDGE WAS CENTERED OVER NEW MEXICO AND
TEXAS WITH THE MAIN H3 JET OVER SOUTHERN CANADA AND A WEAKER JET
SEGMENT OVER ARIZONA. WEAK SHORTWAVES WERE EMBEDDED IN THE FLOW
OVER COLORADO...WESTERN NEBRASKA AND SOUTHEAST WYOMING. WARM MID
LEVEL TEMPERATURES COVERED MUCH OF THE PLAINS WITH A LARGE AREA OF
+14-16DEG C TEMPERATURES AT H7. DEEP MOISTURE WAS IN PLACE FROM
TEXAS INTO THE PLAINS.
WILL CONTINUE TO MONITOR FOR THE DEVELOPMENT OF STRATUS DURING
THE EARLY MORNING HOURS AS THE LOW LEVEL JET INCREASES WITH
SURFACE DEWPOINTS IN THE UPPER 60S AND LOWER 70S. STRONG THETA-E
ADVECTION WILL OCCUR OVERNIGHT AND SHIFT INTO IOWA. THE RAP AND
THE HOPWRF TRY TO DEVELOP STORMS TOWARD FALLS CITY OR KANSAS CITY AND
THE GFS NEAR THE MISSOURI RIVER INTO WESTERN IOWA. ALTHOUGH THERE
IS A LOT OF POTENTIAL...THE STORMS WILL HAVE A TOUGH TIME
DEVELOPING WITH SUCH WARM AIR IN PLACE.
SURFACE LOW PRESSURE WILL TRACK FROM THE WESTERN DAKOTAS INTO
EASTERN SOUTH DAKOTA/MINNESOTA THROUGH TONIGHT. SEVERE WEATHER IS
FORECAST ESPECIALLY FOR NORTH DAKOTA INTO MINNESOTA. FOR OUR
AREA...THIS WILL RESULT IN HOT AIR AHEAD OF THE FRONT WITH HIGHS
IN THE 90S AND EVEN A FEW TRIPLE DIGIT READINGS FOR THE FORECAST
AREA. DUE TO THE HEAT AND THE HUMIDITY...HAVE CONTINUED THE HEAT
ADVISORY THROUGH THE EARLY EVENING HOURS WITH HIGHEST HEAT INDEX
VALUES OF 108 TO 114 DEGREES. AS TEMPERATURES TOP OUT IN THE
UPPER 90S AND LOW TRIPLE DIGITS...SOME STORMS MAY TRY TO DEVELOP.
AGAIN...THERE IS A LOT OF POTENTIAL...HOWEVER CONVECTIVE
TEMPERATURES MAY NOT BE REACHED...THUS HAVE LEFT MAINLY DRY.
THE FRONT WILL MOVE INTO NORTHEAST NEBRASKA TUESDAY MORNING AND
ACROSS THE FORECAST AREA TUESDAY. AGAIN...HOT TEMPERATURES FROM 95
TO 100 ARE FORECAST AHEAD OF THE FRONT...WITH HIGHS IN THE UPPER
80S BEHIND IT. THE HEAT ADVISORY HAS BEEN EXTENDED FOR THOSE
AREAS WHERE HEAT INDEX EXCEEDS 105 DEGREES TUESDAY. IF THE FRONT
MOVES IN FASTER...THE HEADLINE AREA MAY NEED TO BE TRIMMED.
ISOLATED STORMS MAY TRY TO DEVELOP. THERE APPEARS TO BE A BETTER
CHANCE AS THE FRONT MOVES INTO SOUTHEAST NEBRASKA AND FAR
SOUTHWEST IOWA...SO HAVE MAINTAINED POPS THERE TUESDAY AFTERNOON
AND TUESDAY NIGHT. PWAT VALUES WILL BE HIGH AHEAD OF THE
FRONT...SO HEAVY RAIN WILL BE POSSIBLE WITH STORMS THAT FORM.
SURFACE HIGH PRESSURE WILL BUILDS IN FOR WEDNESDAY. LOOK FOR
COOLER HIGHS IN THE 80S.
.LONG TERM...(WEDNESDAY NIGHT THROUGH SUNDAY)
ISSUED AT 335 AM CDT MON JUL 21 2014
A LOW LEVEL JET DEVELOPS WEDNESDAY NIGHT. STORMS OVER SOUTH DAKOTA MAY
HOLD TOGETHER ON THE EDGE OF THE CAP INTO NORTHEAST NEBRASKA AND
PARTS OF THE REST OF THE FORECAST AREA THURSDAY AND THURSDAY
NIGHT. THE MID LEVEL RIDGE RETURNS FOR THURSDAY AND AND A FRONT
MOVES INTO THE REGION FRIDAY AND FRIDAY NIGHT. RISING HEIGHTS WILL
RETURN WARMER TEMPERATURES IN THE MID AND UPPER 80S THURSDAY AND
UPPER 80S AND LOWER 90S FRIDAY. WITH THE FRONT...THERE IS A CHANCE
FOR THUNDERSTORMS FRIDAY AND FRIDAY NIGHT. ONCE AGAIN THE COVERAGE
WILL BE LIMITED WHERE MID LEVEL TEMPERATURES ARE WARMER. SATURDAY
THROUGH MONDAY MAY BE MAINLY DRY WITH HIGHS IN THE 80S. READINGS
MAY BE A LITTLE COOLER MONDAY IF THE TROF OVER THE GREAT LAKES
EXPANDS FAR ENOUGH INTO THE MISSOURI RIVER VALLEY.
&&
.AVIATION...(18Z TAFS FOR KOFK...KLNK AND KOMA.)
ISSUED AT 1225 PM CDT MON JUL 21 2014
SOUTHERLY WINDS WILL CONTINUE THIS AFTERNOON WITH SOME GUSTS 20-25
KNOTS. LOOK FOR MAINLY VFR CONDITIONS. SOME FOG IS POSSIBLE LATE
TONIGHT BUT CHANCES SEEMED LOW ENOUGH TO LEAVE OUT OF TAFS FOR NOW.
&&
.OAX WATCHES/WARNINGS/ADVISORIES...
NE...HEAT ADVISORY UNTIL 8 PM CDT TUESDAY FOR NEZ034-043>045-050>053-
065>068-078-088>093.
HEAT ADVISORY UNTIL 9 PM CDT THIS EVENING FOR NEZ011-012-015>018-
030>033-042.
IA...HEAT ADVISORY UNTIL 8 PM CDT TUESDAY FOR IAZ043-055-056-069-079-
080-090-091.
&&
$$
UPDATE...MILLER
SHORT TERM...ZAPOTOCNY
LONG TERM...ZAPOTOCNY
AVIATION...MILLER
AREA FORECAST DISCUSSION
NWS OMAHA/VALLEY NE
600 AM CDT MON JUL 21 2014
.SHORT TERM...(TODAY THROUGH WEDNESDAY)
ISSUED AT 335 AM CDT MON JUL 21 2014
SHORT TERM FORECAST CONCERNS WILL BE STRATUS DEVELOPMENT AND IF
ANY ISOLATED TSRA CAN DEVELOP...THEN HEAT HEADLINES FOR TODAY AND
TUESDAY.
THE 00Z OAX SOUNDING WAS UNSTABLE...BUT CAPPED WITH 1.54 INCHES OF
PWAT. THE MID TROPOSPHERIC RIDGE WAS CENTERED OVER NEW MEXICO AND
TEXAS WITH THE MAIN H3 JET OVER SOUTHERN CANADA AND A WEAKER JET
SEGMENT OVER ARIZONA. WEAK SHORTWAVES WERE EMBEDDED IN THE FLOW
OVER COLORADO...WESTERN NEBRASKA AND SOUTHEAST WYOMING. WARM MID
LEVEL TEMPERATURES COVERED MUCH OF THE PLAINS WITH A LARGE AREA OF
+14-16DEG C TEMPERATURES AT H7. DEEP MOISTURE WAS IN PLACE FROM
TEXAS INTO THE PLAINS.
WILL CONTINUE TO MONITOR FOR THE DEVELOPMENT OF STRATUS DURING
THE EARLY MORNING HOURS AS THE LOW LEVEL JET INCREASES WITH
SURFACE DEWPOINTS IN THE UPPER 60S AND LOWER 70S. STRONG THETA-E
ADVECTION WILL OCCUR OVERNIGHT AND SHIFT INTO IOWA. THE RAP AND
THE HOPWRF TRY TO DEVELOP STORMS TOWARD FALLS CITY OR KANSAS CITY AND
THE GFS NEAR THE MISSOURI RIVER INTO WESTERN IOWA. ALTHOUGH THERE
IS A LOT OF POTENTIAL...THE STORMS WILL HAVE A TOUGH TIME
DEVELOPING WITH SUCH WARM AIR IN PLACE.
SURFACE LOW PRESSURE WILL TRACK FROM THE WESTERN DAKOTAS INTO
EASTERN SOUTH DAKOTA/MINNESOTA THROUGH TONIGHT. SEVERE WEATHER IS
FORECAST ESPECIALLY FOR NORTH DAKOTA INTO MINNESOTA. FOR OUR
AREA...THIS WILL RESULT IN HOT AIR AHEAD OF THE FRONT WITH HIGHS
IN THE 90S AND EVEN A FEW TRIPLE DIGIT READINGS FOR THE FORECAST
AREA. DUE TO THE HEAT AND THE HUMIDITY...HAVE CONTINUED THE HEAT
ADVISORY THROUGH THE EARLY EVENING HOURS WITH HIGHEST HEAT INDEX
VALUES OF 108 TO 114 DEGREES. AS TEMPERATURES TOP OUT IN THE
UPPER 90S AND LOW TRIPLE DIGITS...SOME STORMS MAY TRY TO DEVELOP.
AGAIN...THERE IS A LOT OF POTENTIAL...HOWEVER CONVECTIVE
TEMPERATURES MAY NOT BE REACHED...THUS HAVE LEFT MAINLY DRY.
THE FRONT WILL MOVE INTO NORTHEAST NEBRASKA TUESDAY MORNING AND
ACROSS THE FORECAST AREA TUESDAY. AGAIN...HOT TEMPERATURES FROM 95
TO 100 ARE FORECAST AHEAD OF THE FRONT...WITH HIGHS IN THE UPPER
80S BEHIND IT. THE HEAT ADVISORY HAS BEEN EXTENDED FOR THOSE
AREAS WHERE HEAT INDEX EXCEEDS 105 DEGREES TUESDAY. IF THE FRONT
MOVES IN FASTER...THE HEADLINE AREA MAY NEED TO BE TRIMMED.
ISOLATED STORMS MAY TRY TO DEVELOP. THERE APPEARS TO BE A BETTER
CHANCE AS THE FRONT MOVES INTO SOUTHEAST NEBRASKA AND FAR
SOUTHWEST IOWA...SO HAVE MAINTAINED POPS THERE TUESDAY AFTERNOON
AND TUESDAY NIGHT. PWAT VALUES WILL BE HIGH AHEAD OF THE
FRONT...SO HEAVY RAIN WILL BE POSSIBLE WITH STORMS THAT FORM.
SURFACE HIGH PRESSURE WILL BUILDS IN FOR WEDNESDAY. LOOK FOR
COOLER HIGHS IN THE 80S.
.LONG TERM...(WEDNESDAY NIGHT THROUGH SUNDAY)
ISSUED AT 335 AM CDT MON JUL 21 2014
A LOW LEVEL JET DEVELOPS WEDNESDAY NIGHT. STORMS OVER SOUTH DAKOTA MAY
HOLD TOGETHER ON THE EDGE OF THE CAP INTO NORTHEAST NEBRASKA AND
PARTS OF THE REST OF THE FORECAST AREA THURSDAY AND THURSDAY
NIGHT. THE MID LEVEL RIDGE RETURNS FOR THURSDAY AND AND A FRONT
MOVES INTO THE REGION FRIDAY AND FRIDAY NIGHT. RISING HEIGHTS WILL
RETURN WARMER TEMPERATURES IN THE MID AND UPPER 80S THURSDAY AND
UPPER 80S AND LOWER 90S FRIDAY. WITH THE FRONT...THERE IS A CHANCE
FOR THUNDERSTORMS FRIDAY AND FRIDAY NIGHT. ONCE AGAIN THE COVERAGE
WILL BE LIMITED WHERE MID LEVEL TEMPERATURES ARE WARMER. SATURDAY
THROUGH MONDAY MAY BE MAINLY DRY WITH HIGHS IN THE 80S. READINGS
MAY BE A LITTLE COOLER MONDAY IF THE TROF OVER THE GREAT LAKES
EXPANDS FAR ENOUGH INTO THE MISSOURI RIVER VALLEY.
&&
.AVIATION...(12Z TAFS FOR KOFK...KLNK AND KOMA.)
ISSUED AT 557 AM CDT MON JUL 21 2014
LOWER STRATUS DECK HAS NOT DEVELOPED AS EXTENSIVELY THIS
MORNING...ALTHOUGH OBS AND SATELLITE INDICATE THERE COULD BE SOME
PATCHY LOWER CLOUDS THAT COULD AFFECT KOMA FOR A FEW HOURS THIS
MORNING. OTHERWISE...SCATTERED TO BROKEN CIRRUS CLOUDS WILL STREAM
IN FROM THE WEST THIS MORNING...AND A CU FIELD IS LIKELY TO
DEVELOP AS WELL. SOUTHERLY WINDS WILL ALSO INCREASE WTO 14 TO 23
KNOTS BY 17/18Z...BUT THEN DIMINISH 12 KNOTS OR LESS BY 22/00-01Z.
&&
.OAX WATCHES/WARNINGS/ADVISORIES...
NE...HEAT ADVISORY FROM 1 PM THIS AFTERNOON TO 8 PM CDT TUESDAY FOR
NEZ034-043>045-050>053-065>068-078-088>093.
HEAT ADVISORY FROM 1 PM THIS AFTERNOON TO 9 PM CDT THIS EVENING
FOR NEZ011-012-015>018-030>033-042.
IA...HEAT ADVISORY FROM 1 PM THIS AFTERNOON TO 8 PM CDT TUESDAY FOR
IAZ043-055-056-069-079-080-090-091.
&&
$$
SHORT TERM...ZAPOTOCNY
LONG TERM...ZAPOTOCNY
AVIATION...DEWALD
AREA FORECAST DISCUSSION
NWS OMAHA/VALLEY NE
401 AM CDT MON JUL 21 2014
.SHORT TERM...(TODAY THROUGH WEDNESDAY)
ISSUED AT 335 AM CDT MON JUL 21 2014
SHORT TERM FORECAST CONCERNS WILL BE STRATUS DEVELOPMENT AND IF
ANY ISOLATED TSRA CAN DEVELOP...THEN HEAT HEADLINES FOR TODAY AND
TUESDAY.
THE 00Z OAX SOUNDING WAS UNSTABLE...BUT CAPPED WITH 1.54 INCHES OF
PWAT. THE MID TROPOSPHERIC RIDGE WAS CENTERED OVER NEW MEXICO AND
TEXAS WITH THE MAIN H3 JET OVER SOUTHERN CANADA AND A WEAKER JET
SEGMENT OVER ARIZONA. WEAK SHORTWAVES WERE EMBEDDED IN THE FLOW
OVER COLORADO...WESTERN NEBRASKA AND SOUTHEAST WYOMING. WARM MID
LEVEL TEMPERATURES COVERED MUCH OF THE PLAINS WITH A LARGE AREA OF
+14-16DEG C TEMPERATURES AT H7. DEEP MOISTURE WAS IN PLACE FROM
TEXAS INTO THE PLAINS.
WILL CONTINUE TO MONITOR FOR THE DEVELOPMENT OF STRATUS DURING
THE EARLY MORNING HOURS AS THE LOW LEVEL JET INCREASES WITH
SURFACE DEWPOINTS IN THE UPPER 60S AND LOWER 70S. STRONG THETA-E
ADVECTION WILL OCCUR OVERNIGHT AND SHIFT INTO IOWA. THE RAP AND
THE HOPWRF TRY TO DEVELOP STORMS TOWARD FALLS CITY OR KANSAS CITY AND
THE GFS NEAR THE MISSOURI RIVER INTO WESTERN IOWA. ALTHOUGH THERE
IS A LOT OF POTENTIAL...THE STORMS WILL HAVE A TOUGH TIME
DEVELOPING WITH SUCH WARM AIR IN PLACE.
SURFACE LOW PRESSURE WILL TRACK FROM THE WESTERN DAKOTAS INTO
EASTERN SOUTH DAKOTA/MINNESOTA THROUGH TONIGHT. SEVERE WEATHER IS
FORECAST ESPECIALLY FOR NORTH DAKOTA INTO MINNESOTA. FOR OUR
AREA...THIS WILL RESULT IN HOT AIR AHEAD OF THE FRONT WITH HIGHS
IN THE 90S AND EVEN A FEW TRIPLE DIGIT READINGS FOR THE FORECAST
AREA. DUE TO THE HEAT AND THE HUMIDITY...HAVE CONTINUED THE HEAT
ADVISORY THROUGH THE EARLY EVENING HOURS WITH HIGHEST HEAT INDEX
VALUES OF 108 TO 114 DEGREES. AS TEMPERATURES TOP OUT IN THE
UPPER 90S AND LOW TRIPLE DIGITS...SOME STORMS MAY TRY TO DEVELOP.
AGAIN...THERE IS A LOT OF POTENTIAL...HOWEVER CONVECTIVE
TEMPERATURES MAY NOT BE REACHED...THUS HAVE LEFT MAINLY DRY.
THE FRONT WILL MOVE INTO NORTHEAST NEBRASKA TUESDAY MORNING AND
ACROSS THE FORECAST AREA TUESDAY. AGAIN...HOT TEMPERATURES FROM 95
TO 100 ARE FORECAST AHEAD OF THE FRONT...WITH HIGHS IN THE UPPER
80S BEHIND IT. THE HEAT ADVISORY HAS BEEN EXTENDED FOR THOSE
AREAS WHERE HEAT INDEX EXCEEDS 105 DEGREES TUESDAY. IF THE FRONT
MOVES IN FASTER...THE HEADLINE AREA MAY NEED TO BE TRIMMED.
ISOLATED STORMS MAY TRY TO DEVELOP. THERE APPEARS TO BE A BETTER
CHANCE AS THE FRONT MOVES INTO SOUTHEAST NEBRASKA AND FAR
SOUTHWEST IOWA...SO HAVE MAINTAINED POPS THERE TUESDAY AFTERNOON
AND TUESDAY NIGHT. PWAT VALUES WILL BE HIGH AHEAD OF THE
FRONT...SO HEAVY RAIN WILL BE POSSIBLE WITH STORMS THAT FORM.
SURFACE HIGH PRESSURE WILL BUILDS IN FOR WEDNESDAY. LOOK FOR
COOLER HIGHS IN THE 80S.
.LONG TERM...(WEDNESDAY NIGHT THROUGH SUNDAY)
ISSUED AT 335 AM CDT MON JUL 21 2014
A LOW LEVEL JET DEVELOPS WEDNESDAY NIGHT. STORMS OVER SOUTH DAKOTA MAY
HOLD TOGETHER ON THE EDGE OF THE CAP INTO NORTHEAST NEBRASKA AND
PARTS OF THE REST OF THE FORECAST AREA THURSDAY AND THURSDAY
NIGHT. THE MID LEVEL RIDGE RETURNS FOR THURSDAY AND AND A FRONT
MOVES INTO THE REGION FRIDAY AND FRIDAY NIGHT. RISING HEIGHTS WILL
RETURN WARMER TEMPERATURES IN THE MID AND UPPER 80S THURSDAY AND
UPPER 80S AND LOWER 90S FRIDAY. WITH THE FRONT...THERE IS A CHANCE
FOR THUNDERSTORMS FRIDAY AND FRIDAY NIGHT. ONCE AGAIN THE COVERAGE
WILL BE LIMITED WHERE MID LEVEL TEMPERATURES ARE WARMER. SATURDAY
THROUGH MONDAY MAY BE MAINLY DRY WITH HIGHS IN THE 80S. READINGS
MAY BE A LITTLE COOLER MONDAY IF THE TROF OVER THE GREAT LAKES
EXPANDS FAR ENOUGH INTO THE MISSOURI RIVER VALLEY.
&&
.AVIATION...(06Z TAFS FOR KOFK...KLNK AND KOMA.)
ISSUED AT 1105 PM CDT SUN JUL 20 2014
SOME INDICATION FROM EVENING MODELS THAT LOW CLOUDS COULD INDEED
FORM AGAIN BY MORNING AS HAD BEEN THE CASE THE PAST SEVERAL DAYS.
SO EVEN THOUGH TEMPERATURE-DEW POINT SPREAD COULD REMAIN GREATER
THAT PAST FEW MORNINGS AS READINGS/WINDS WERE A LITTLE
HIGHER...DECIDED TO INCLUDE A TEMPO GROUP OF CIGS NEAR FL010 FOR A
FEW HOURS MONDAY MORNING. OTHERWISE...WOULD EXPECT A RELATIVELY
QUICK EROSION IN THE LOWER CLOUDS...IF THEY DO INDEED FORM...AS
TEMPERATURES/WINDS INCREASE BY MID MORNING.
&&
.OAX WATCHES/WARNINGS/ADVISORIES...
NE...HEAT ADVISORY FROM 1 PM THIS AFTERNOON TO 8 PM CDT TUESDAY FOR
NEZ034-043>045-050>053-065>068-078-088>093.
HEAT ADVISORY FROM 1 PM THIS AFTERNOON TO 9 PM CDT THIS EVENING
FOR NEZ011-012-015>018-030>033-042.
IA...HEAT ADVISORY FROM 1 PM THIS AFTERNOON TO 8 PM CDT TUESDAY FOR
IAZ043-055-056-069-079-080-090-091.
&&
$$
SHORT TERM...ZAPOTOCNY
LONG TERM...ZAPOTOCNY
AVIATION...CHERMOK
AREA FORECAST DISCUSSION...UPDATED
NWS ALBUQUERQUE NM
1154 PM MDT SUN JUL 20 2014
.AVIATION...
06Z TAF CYCLE
ISOLATED SHOWERS AND PERHAPS A STRAY THUNDERSTORM WILL CONTINUE TO
DRIFT TO THE NORTH MAINLY OVER CENTRAL ZONES. THIS ACTIVITY WILL
GRADUALLY DISSIPATE BUT SPOTTY SHOWERS COULD PERSIST THROUGH 10Z.
VFR CONDITIONS EXPECTED THROUGH ABOUT 18Z. THUNDERSTORMS TO
DEVELOP OVER THE HIGHER TERRAIN AND CENTRAL HIGHLANDS
THEREAFTER... WITH LOCAL MVFR CIGS AND VSBYS AND OCCASIONAL
MOUNTAIN OBSCURATIONS...WITH BEST CHANCES FOR THUNDERSTORMS LIKELY
AROUND KLVS IN THE AFTERNOON AND KTCC IN THE EVENING.
05
&&
.PREV DISCUSSION...311 PM MDT SUN JUL 20 2014...
.SYNOPSIS...
SLOW MOVING SHOWERS AND THUNDERSTORMS WITH LOCALLY HEAVY RAINFALL
WILL CONTINUE THROUGH TUESDAY FOR PORTIONS OF CENTRAL AND EASTERN
NEW MEXICO. THE COVERAGE OF THIS ACTIVITY WILL BE MORE ISOLATED IN
NATURE THAN RECENT WEEKS. A STRONG AREA OF HIGH PRESSURE WILL THEN
SHIFT OVER THE STATE WEDNESDAY AND BRING THE HOTTEST TEMPERATURES
IN QUITE A WHILE FOR CENTRAL AND WESTERN NEW MEXICO. MANY LOWER
ELEVATION AREAS WILL TOP OUT IN THE MID 90S TO LOW 100S. THE HIGH
WILL THEN SHIFT WEST AND ALLOW SEVERAL MOIST BACK DOOR FRONTS TO
SHIFT WESTWARD INTO THE STATE. THIS WILL TAPER OFF THE HEAT AND
INTRODUCE ANOTHER ROUND OF MORE SCATTERED THUNDERSTORMS FRIDAY INTO
THE WEEKEND.
&&
.DISCUSSION...
FORECAST CONFIDENCE FOR THIS EVENING IS VERY LOW BUT WITH MODERATE
POTENTIAL IMPACT. SHORT-TERM MODEL GUIDANCE IS ALL OVER THE PLACE
WITH RESPECT TO PLACEMENT OF CONVECTIVE FEATURES THIS EVENING. THE
20Z SURFACE DEWPOINT VALUES ARE CRATERING OVER MUCH OF THE REGION
DESPITE ABUNDANT MID AND UPPER LEVEL MOISTURE. THE BEST MOISTURE IS
POOLING AROUND THE MIDDLE RIO GRANDE VALLEY AND OVER THE SE PLAINS.
THE LATEST HRRR AND 12Z GFS ARE PICKING UP ON A CONVECTIVE COMPLEX
MOVING FROM THE DIVIDE TO NEAR THE ABQ METRO THIS EVENING. THE 06Z
WRF AND NAM GUIDANCE SHOWED THIS EARLIER BUT BACKED OFF ON IT FOR
THE 12Z RUN. QPF VALUES COULD BE HIGH BENEATH A SLOW MOVING SOUTH
TO NORTH COMPLEX BUT PLACEMENT AND DURATION IS VERY QUESTIONABLE.
PLACED CHANCE POPS OVER A LARGE AREA OF CENTRAL NM AS A RESULT. THE
OTHER WRINKLE IS THE HRRR SHOWS A LARGE AREA OF PRECIP SHIFTING
NORTH AFTER 06Z UP THE LOWER RIO GRANDE VALLEY. WOULD NOT BE
SURPRISED TO SEE THIS OCCUR AS THE LATEST IR SHOWS SOME VIGOROUS
CONVECTION ERUPTING OVER NORTH CENTRAL MEXICO.
THE GFS ENSEMBLE AND SREF SHOW WITH VERY GOOD AGREEMENT THE CURRENT
594DM H5 HIGH CENTERED OVER SOUTHEAST NM SHIFTING NORTH MONDAY AND
TUESDAY AND BUILDING TO 599DM OVER SOUTHERN COLORADO. THIS INTRODUCES
ANOTHER TOSS UP AS HEIGHTS RISE WELL ABOVE NORMAL BUT AN AXIS OF MID
LEVEL MOISTURE ROTATES WEST FROM WEST/CENTRAL TX. SEVERAL DAYS AGO
MODELS WERE CONSERVATIVE WITH CONVECTIVE DEVELOPMENT BUT TRENDS HAVE
BEEN FOR MORE COVERAGE...PARTICULARLY TUESDAY. MADE ONLY SUBTLE POP
CHANGES TO INCREASE VALUES OVER THE PLAINS. OTHERWISE...EXPECT AT
LEAST HOT TEMPS.
BEYOND WEDNESDAY THE UPPER HIGH WILL TREND TOWARD THE WEST WHILE YET
ANOTHER VERY STRONG SUMMER UPPER LOW SLIDES INTO THE GREAT LAKES.
THE TRANSITION PERIOD FOR THURSDAY/FRIDAY IS ALSO LOW CONFIDENCE
DEPENDING ON HOW THE HIGH WARPS AND DRIFTS WESTWARD. A STRONG BACK
DOOR FRONT IS THEN DEPICTED SATURDAY THROUGH EARLY NEXT WEEK AS A
FOCUS MECHANISM FOR MORE CONVECTION OVER NM. THIS IS MOST CERTAINLY
NOT ANYWHERE NEAR THE TYPE OF PATTERN THAT ONE WOULD EXPECT TO SEE
OVER THE CONUS DURING LATE JULY.
GUYER
&&
.FIRE WEATHER...
WHILE TODAYS SHOWER AND STORM CROP HAS BEEN A SLOW STARTER...IT MAY
END UP TO BE NEARLY AS GOOD OR BETTER COVERAGE IN CENTRAL AND
SOUTHERN PORTIONS OF THE FORECAST AREA BY LATE AFTN OR EVE. THE BULK
OF THE BURN SCAR AREAS WILL CONTINUE TO HAVE SOME RISK OF HEAVY
RUNOFF OR WORSE THROUGH THE EVE. THE AMOUNT AND LOCATION OF THE
MAXIMUM SHOWER AND THUNDERSTORM ACTIVITY WILL VARY A FAIR DEGREE
FROM DAY TO DAY ACROSS THE NEXT 5 TO 7 DAYS...PROBABLY SHIFTING A
LITTLE WAYS TO THE EAST AND SOUTH MON AND THEN BACK TO THE WEST AND
NORTH TUE AND WED. IT BECOMES A LITTLE LESS CERTAIN THEREAFTER...AS
TO LOCATION AND DEGREE OF COVERAGE...BUT LONGER RANGE FORECAST MODEL
DATA SEEMS TO AGREE PRETTY WELL THAT A MODERATE TO STRONG BACK DOOR
COLD FRONT FOR THIS TIME OF YEAR WILL PUSH INTO AND ACROSS AT LEAST
EAST AND CENTRAL NM AND PERHAPS EVEN FARTHER WEST SAT NIGHT INTO
SUN. THIS SHOULD GENERATE A MODERATE TO ROBUST INCREASE IN SHOWERS
AND STORMS NEAR AND BEHIND ITS PASSAGE BETWEEN LATE SAT AND MON.
UNTIL THEN HOWEVER...ABOVE NORMAL TEMPERATURES AND AT LEAST SLIGHTLY
BELOW NORMAL THUNDERSTORM ACTIVITY FOR MID TO LATE JULY CAN BE
EXPECTED DUE TO A DOMINANT UPPER HIGH OVER THE REGION.
NO CRITICAL WIND SPEEDS ARE EXPECTED OVER THE NEXT 5 TO 7 DAYS AT
LEAST...COMMON FOR THIS TIME OF YEAR...BUT MINIMUM RHS HAVE REACHED
MARGINALLY CRITICAL LEVELS ACROSS A FEW SITES ACROSS NORTH NM AND
EVEN THE LOWER RIO GRANDE VALLEY. THIS MAY EXPAND SOMEWHAT BETWEEN
MON AND WED...BUT SUBSIDE SOME AGAIN BY LATE WEEK OR THE WEEKEND
HAINES INDICES ARE FORECAST TO TREND UP SOME MON AND PERHAPS
TUE...THEN DROP SOME WED AND THU BEFORE TRENDING BACK UP NEAR END OF
WEEK. OVERNIGHT RH RECOVERIES WILL VARY FROM FAIR TO VERY
GOOD...DEPENDING IN LARGE PART ON WHERE THE MORE SIGNIFICANT
RAINFALL HAS FALLEN ON A PARTICULAR DAY.
43
&&
.ABQ WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS GRAND FORKS ND
316 PM CDT MON JUL 21 2014
.SHORT TERM...(THIS EVENING THROUGH TUESDAY NIGHT)
ISSUED AT 315 PM CDT MON JUL 21 2014
CONVECTION TIMING AND SEVERITY WILL BE THE MAIN FORECAST HEADACHE
FOR THE SHORT TERM.
STORMS HAVE DEVELOPED OVER WESTERN ND A FEW HOURS SOONER THAN
ORIGINALLY THOUGHT. A LITTLE BIT OF ACTIVITY HAS FIRED NORTH OF
THE BOUNDARY IN THE UPPER DEVILS LAKE BASIN...BUT CONVECTION IN
THAT AREA HAS BEEN SUB SEVERE SO FAR. THE STRONGEST ACTIVITY HAS
BEEN IN THE WESTERN PART OF THE STATE WITH THE MAIN
SHORTWAVE...BUT OUR NORTHWESTERN COUNTIES WILL BE UNDER THE GUN IN
THE NEXT FEW HOURS AS THE SHORTWAVE MOVES CLOSER AND THE
ATMOSPHERE CONTINUES TO DESTABILIZE WITH ML CAPE ABOVE 3000 J/KG.
WITH A SFC BOUNDARY HANGING AROUND IN THE AREA...THERE COULD BE
ENOUGH LOW LEVEL HELICITY TO GET STORMS TURNING IF THEY ARE
ISOLATED ENOUGH. THUS...TORNADO WATCH FOR OUR NORTHWEST EARLY ON
IN THIS EVENT.
LATER ON TONIGHT...THE THUNDERSTORMS ARE EXPECTED TO EVOLVE INTO A
COMPLEX MOVING ACROSS THE CWA. WITH PLENTY OF MOISTURE FEEDING
INTO THE COMPLEX AS DEW POINTS RISE INTO THE 70S...AND THE HIGHLY
UNSTABLE AIR MASS...STORMS SHOULD MAINTAIN THEMSELVES AS THEY MOVE
INTO THE RED RIVER VALLEY AND THEN INTO MN. BULK SHEAR VALUES ARE
AROUND 40 TO 50 KTS ALTHOUGH THE LOW LEVEL SHEAR IS NOT NEARLY AS
STRONG AS NEAR THE SFC BOUNDARY. MODEL SOLUTIONS CONTINUE TO POINT
TO A BOW ECHO TYPE PATTERN...AND THE HRRR HAS BEEN CONSISTENT ON
SHOWING HIGH WIND GUSTS ALONG WITH THE STORMS. SIGNS CONTINUE TO
POINT TO A MCS ARRIVING IN THE VALLEY THIS EVENING AND MOVING
EASTWARD INTO MN AFTER MIDNIGHT. DERACHO COMPOSITE ON THE SPC MESO
PAGE IS IN THE 6 TO 8 RANGE...SO WILL KEEP THE DAMAGING WIND TAGS
IN THE GRIDS FOR THIS EVENING.
THE OTHER THREAT WILL BE HEAVY RAINFALL. THE MODELS CONTINUE TO
CRANK OUT BULLSEYES OF OVER 2 INCHES IN A VERY SHORT TIME
PERIOD. WITH PWAT VALUES UP TO 1.5 INCHES AND 850MB MOISTURE
TRANSPORT CONTINUING TO PUSH MORE MOISTURE INTO OUR
COUNTIES...HEAVY RAINFALL CONTINUES TO SEEM REASONABLE. THE ISSUE
WILL BE WHERE IT FALL AND HOW LONG THE PRECIP WILL LAST. MANY OF
THE SHORT RANGE MODELS HAVE BEEN TRENDING FURTHER NORTH WITH THE
TRACK OF THE CONVECTION...WHICH WOULD TAKE IT ALONG THE NORTHERN
EDGE OF THE MOST WARM AND MOIST AIR. THE FLY IN THE OINTMENT WILL
BE THE MOVEMENT OF THE STORMS AS THE COMPLEX ACCELERATES ACROSS
THE CWA. SINCE THERE HAS BEEN FAIRLY DRY WEATHER THE PAST FEW
WEEKS OVER THE VALLEY...WILL HOLD OFF ON ANY FLOOD WATCHES FOR
NOW BUT HAVE TO KEEP AN EYE ON THE STORMS AS THEY APPROACH THE MN
LAKES COUNTRY LATER TONIGHT.
THERE COULD BE SOME LINGERING SHOWERS AND STORMS IN THE EASTERN
COUNTIES TOWARDS TOMORROW MORNING...BUT THERE SHOULD BE A DRYING
TREND AS A COLD FRONT MOVES IN AND HIGH PRESSURE ARRIVES. TUESDAY
WILL BE QUITE A BIT COOLER THAN TODAY...WITH HIGHS IN THE 70S TO
LOW 80S AND DEW POINTS BACK DOWN INTO THE 50S. SFC HIGH PRESSURE
WILL CONTINUE INTO TUESDAY NIGHT AND KEEP LOWS MUCH COOLER THAN
THEY HAVE BEEN THE PAST FEW NIGHTS.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 315 PM CDT MON JUL 21 2014
WEDNESDAY TO MONDAY...MODELS IN FAIR AGREEMENT WITH THE EXTENDED
TIME FRAME. OVERALL TEMPS REGIME WILL BE NORMAL TO BELOW NORMAL
TEMPS WITH DRY WEATHER FEATURED MOST DAYS AS SFC HIGH PRESSURE
COMBINED WITH PREDOMINANTLY NW FLOW ALOFT PERSISTS. THE EXCEPTION IS
THURSDAY NIGHT INTO FRIDAY AND SUNDAY WITH CHC THUNDERSTORMS AS
RIDGING SHUNTS BACK TO THE WEST WITH POTENT SHORT WAVE RIDING OVER
THE TOP BRINGING INSTABILITY AND FORCING TO THE NORTHERN PLAINS.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON)
ISSUED AT 1241 PM CDT MON JUL 21 2014
MVFR FOR BJI WITH SLOWLY ERODING 1500FT DECK. ELSEWHERE VFR FOR THE
AFTN THEN SVR SQUALL LINE EXPECTED TO MOVE FROM WEST TO EAST THIS
EVENING IMPACTING DVL AROUND 23-01Z GFK AND FAR 01-03Z AND TVF BJI
BY 02-04Z.
&&
.FGF WATCHES/WARNINGS/ADVISORIES...
ND...HEAT ADVISORY UNTIL 7 PM CDT THIS EVENING FOR NDZ039-049-052-053.
MN...HEAT ADVISORY UNTIL 7 PM CDT THIS EVENING FOR MNZ003-029>032-040.
&&
$$
SHORT TERM...JR
LONG TERM...JK
AVIATION...JK
AREA FORECAST DISCUSSION
NWS BISMARCK ND
1054 AM CDT MON JUL 21 2014
.UPDATE...
ISSUED AT 1053 AM CDT MON JUL 21 2014
EARLY UPDATE...LINE OF SHOWERS AND THUNDERSTORMS HAVE DEVELOPED
OVER NORTHEAST MONTANA...AND ARE MOVING NORTHEAST. OTHER AREAS OF
SHOWERS DEVELOPING OVER SOUTHWEST NORTH DAKOTA AND FAR SOUTHERN
NORTH DAKOTA. MONITORING THESE AREAS CLOSELY. THE MAIN TIMING FOR
SEVERE WEATHER IS STILL ON TRACK...IN THE WEST BETWEEN 18Z AND
21Z...CENTRAL 21Z TO 01Z.
UPDATE ISSUED AT 740 AM CDT MON JUL 21 2014
LATEST WATER VAPOR IMAGERY SHOWS SEVERAL SHORTWAVES EMBEDDED
WITHIN A SOUTHWEST FLOW FROM SOUTHWEST MONTANA INTO CENTRAL/EASTERN
IDAHO...MOVING NORTHEAST TOWARD WESTERN NORTH DAKOTA. A 55KT JET
WAS SEEN PUNCHING THROUGH UTAH AND WYOMING...WHICH WILL FURTHER
ENHANCE LARGE SCALE ASCENT THIS AFTERNOON AND EVENING. FOCUS AND
SITUATIONAL AWARENESS COMPLETELY ON MONITORING SEVERE WEATHER
THROUGH THE DAY AND EVENING.
CURRENT REGIONAL/LOCAL RADAR SHOWS SHOWERS AND THE ISOLATED
THUNDERSTORMS OVER SOUTHERN MONTANA AND INTO CENTRAL AND NORTHERN
WYOMING. THE LATEST HRRR SEEMS TO HAVE A DEVELOPING AREA NEAR
SHERIDAN WYOMING HANDLED WELL. THE HRRR SUGGESTS THAT CONVECTION
COULD INITIATE BETWEEN 18Z AND 21Z ALONG A LINE FROM NEAR WATFORD
CITY TO DICKINSON...AND THEN MOVE TO A MINOT TO BISMARCK LINE
BETWEEN 21Z AND 00Z. THE OTHER HIGH RESOLUTION MODELS ARE SIMILAR
IN THE AREA DEVELOPMENT...BUT ARE MORE INTENSE WITH THE AREA AND
ARE QUICKER IN THE OVERALL EASTWARD MOVEMENT LATER THIS AFTERNOON.
WILL CONTINUE TO INTERROGATE SATELLITE/RADAR AND HIGH RESOLUTION
AND MODELS THROUGH THE MORNING.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 429 AM CDT MON JUL 21 2014
THE MAIN FORECAST CHALLENGE TODAY IS SEVERE WEATHER TIMING. THE
LATEST CONVECTION-ALLOWING MODELS CALL FOR EARLY AFTERNOON
CONVECTIVE INITIATION GENERALLY ALONG AND WEST OF U.S. 83.
EASTWARD PROPAGATION OF AN MCS ALONG INTERSTATE 94 IS THE
CONSENSUS SOLUTION...AND IT MATCHES THE STORM PREDICTION CENTER
MODERATE RISK AREA WELL.
THE 21/00 UTC HIRES ARW AND NMM CALL FOR CONVECTIVE INITIATION EVEN
FURTHER WEST AROUND NOON...AND BOTH CALL FOR A LARGE BOW ECHO TO
BE SOMEWHERE BETWEEN GLEN ULLIN AND BISMARCK BY 4 PM CDT. WITH THE
INITIATION AREA MOVING WEST...THE MODERATE RISK AREA MAY HAVE TO
SHIFT A LITTLE WESTWARD. THE STORM PREDICTION CENTER HAS REQUESTED
AN 18 UTC BALLOON BE LAUNCHED...WHICH SHOULD PROVIDE SOME INSIGHT
INTO HOW EXTREME THE INSTABILITY HAS BECOME BY THEN.
BE SURE TO SEE THE DAY 1 STORM PREDICTION CENTER CONVECTIVE
OUTLOOK GRAPHIC AND DISCUSSION FOR MORE DETAILS.
FINALLY...A HEAT ADVISORY WAS ISSUED FOR THREE SOUTHEASTERN
COUNTIES. THE SURFACE LOW TRACK HAS SHIFTED NORTHWARD IN THE PAST
36 HOURS OF MODEL RUNS. CONSEQUENTLY...THE WARM SECTOR HAS ALSO
SHIFTED NORTH. HEAT INDICES UP TO 105F ARE NOW FORECAST.
.LONG TERM...(TUESDAY THROUGH SUNDAY)
ISSUED AT 429 AM CDT MON JUL 21 2014
A BRIEF UPPER LEVEL FLOW PATTERN SHIFT FROM PROGRESSIVE TO BLOCKED
OVER THE SOUTHERN TIER OF CANADA DOES NOTHING TO SQUELCH CHANCES
FOR CONVECTION IN THE FORECAST UNTIL SUNDAY.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON)
ISSUED AT 1053 AM CDT MON JUL 21 2014
THUNDERSTORMS WILL DEVELOP ACROSS THE WESTERN TERMINALS THROUGH
21Z AND THEN INTO THE CENTRAL TERMINALS..KBIS/KMOT BETWEEN 21Z
AND 01Z. KJMS CLOSER TO 00Z TUESDAY. SOME THUNDERSTORMS WILL BE
SEVERE WITH DAMAGING WINDS AND LARGE HAIL.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
HEAT ADVISORY UNTIL 9 PM CDT THIS EVENING FOR NDZ048-050-051.
&&
$$
UPDATE...KS
SHORT TERM...SCHECK
LONG TERM...SCHECK
AVIATION...KS
AREA FORECAST DISCUSSION
NWS BISMARCK ND
801 AM CDT MON JUL 21 2014
.UPDATE...
ISSUED AT 740 AM CDT MON JUL 21 2014
LATEST WATER VAPOR IMAGERY SHOWS SEVERAL SHORTWAVES EMBEDDED
WITHIN A SOUTHWEST FLOW FROM SOUTHWEST MONTANA INTO CENTRAL/EASTERN
IDAHO...MOVING NORTHEAST TOWARD WESTERN NORTH DAKOTA. A 55KT JET
WAS SEEN PUNCHING THROUGH UTAH AND WYOMING...WHICH WILL FURTHER
ENHANCE LARGE SCALE ASCENT THIS AFTERNOON AND EVENING. FOCUS AND
SITUATIONAL AWARENESS COMPLETELY ON MONITORING SEVERE WEATHER
THROUGH THE DAY AND EVENING.
CURRENT REGIONAL/LOCAL RADAR SHOWS SHOWERS AND THE ISOLATED
THUNDERSTORMS OVER SOUTHERN MONTANA AND INTO CENTRAL AND NORTHERN
WYOMING. THE LATEST HRRR SEEMS TO HAVE A DEVELOPING AREA NEAR
SHERIDAN WYOMING HANDLED WELL. THE HRRR SUGGESTS THAT CONVECTION
COULD INITIATE BETWEEN 18Z AND 21Z ALONG A LINE FROM NEAR WATFORD
CITY TO DICKINSON...AND THEN MOVE TO A MINOT TO BISMARCK LINE
BETWEEN 21Z AND 00Z. THE OTHER HIGH RESOLUTION MODELS ARE SIMILAR
IN THE AREA DEVELOPMENT...BUT ARE MORE INTENSE WITH THE AREA AND
ARE QUICKER IN THE OVERALL EASTWARD MOVEMENT LATER THIS AFTERNOON.
WILL CONTINUE TO INTERROGATE SATELLITE/RADAR AND HIGH RESOLUTION
AND MODELS THROUGH THE MORNING.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 429 AM CDT MON JUL 21 2014
THE MAIN FORECAST CHALLENGE TODAY IS SEVERE WEATHER TIMING. THE
LATEST CONVECTION-ALLOWING MODELS CALL FOR EARLY AFTERNOON
CONVECTIVE INITIATION GENERALLY ALONG AND WEST OF U.S. 83.
EASTWARD PROPAGATION OF AN MCS ALONG INTERSTATE 94 IS THE
CONSENSUS SOLUTION...AND IT MATCHES THE STORM PREDICTION CENTER
MODERATE RISK AREA WELL.
THE 21/00 UTC HIRES ARW AND NMM CALL FOR CONVECTIVE INITIATION EVEN
FURTHER WEST AROUND NOON...AND BOTH CALL FOR A LARGE BOW ECHO TO
BE SOMEWHERE BETWEEN GLEN ULLIN AND BISMARCK BY 4 PM CDT. WITH THE
INITIATION AREA MOVING WEST...THE MODERATE RISK AREA MAY HAVE TO
SHIFT A LITTLE WESTWARD. THE STORM PREDICTION CENTER HAS REQUESTED
AN 18 UTC BALLOON BE LAUNCHED...WHICH SHOULD PROVIDE SOME INSIGHT
INTO HOW EXTREME THE INSTABILITY HAS BECOME BY THEN.
BE SURE TO SEE THE DAY 1 STORM PREDICTION CENTER CONVECTIVE
OUTLOOK GRAPHIC AND DISCUSSION FOR MORE DETAILS.
FINALLY...A HEAT ADVISORY WAS ISSUED FOR THREE SOUTHEASTERN
COUNTIES. THE SURFACE LOW TRACK HAS SHIFTED NORTHWARD IN THE PAST
36 HOURS OF MODEL RUNS. CONSEQUENTLY...THE WARM SECTOR HAS ALSO
SHIFTED NORTH. HEAT INDICES UP TO 105F ARE NOW FORECAST.
.LONG TERM...(TUESDAY THROUGH SUNDAY)
ISSUED AT 429 AM CDT MON JUL 21 2014
A BRIEF UPPER LEVEL FLOW PATTERN SHIFT FROM PROGRESSIVE TO BLOCKED
OVER THE SOUTHERN TIER OF CANADA DOES NOTHING TO SQUELCH CHANCES
FOR CONVECTION IN THE FORECAST UNTIL SUNDAY.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z TUESDAY MORNING)
ISSUED AT 429 AM CDT MON JUL 21 2014
WIDESPREAD THUNDERSTORMS WILL DEVELOP TODAY...WITH THE GREATEST
CHANCES AFTER 21Z AT KBIS/KMOT/KJMS.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
HEAT ADVISORY FROM 11 AM THIS MORNING TO 9 PM CDT THIS EVENING
FOR NDZ048-050-051.
&&
$$
UPDATE...KS
SHORT TERM...SCHECK
LONG TERM...SCHECK
AVIATION...SCHECK
AREA FORECAST DISCUSSION
NWS WILMINGTON OH
923 PM EDT TUE JUL 22 2014
.SYNOPSIS...
AN APPROACHING COLD FRONT WILL CONTINUE TO KEEP SOUTHWEST WINDS
AND HUMID AIR OVER THE OHIO VALLEY AHEAD OF IT. THIS FRONT WILL
PUSH THROUGH THE REGION WEDNESDAY AND SPARK A ROUND OF SHOWERS
AND THUNDERSTORMS. A LARGE AREA OF HIGH PRESSURE WILL BUILD BEHIND
IT AND PROVIDE DRY AND COOL WEATHER THROUGH THE END OF THE WORK WEEK.
&&
.NEAR TERM /UNTIL 6 AM WEDNESDAY MORNING/...
DIURNAL CU HAVE DISSIPATED ACROSS THE AREA WITH SKIES CURRENTLY
MOSTLY CLEAR. WE SHOULD SEE AN INCREASE IN HIGH AND MID LEVEL
CLOUDS AS WE HEAD INTO THE OVERNIGHT HOURS AS A COLD FRONT
APPROACHES FROM THE NORTHWEST. A NARROW LINE OF SHOWERS AND
THUNDERSTORMS CURRENTLY ALONG THE FRONT STRETCHING FROM SOUTHERN
WISCONSIN INTO LOWER MICHIGAN WILL CONTINUE TO WORK ITS WAY
SOUTHEAST TOWARD OUR AREA OVERNIGHT. THE HRRR CONTINUES TO SUGGEST
THAT SOME OF THIS COULD MAKE IT DOWN INTO OUR NORTHWEST FA THROUGH
THE EARLY MORNING HOURS...WHILE THE ARW AND NMM WEAKEN AND
DISSIPATE THE STORMS AS THEY MOVE INTO OUR AREA. WILL CONTINUE WITH
SOME LOWER CHANCE POPS ACROSS THE NORTHWEST TO ACCOUNT FOR THE
POSSIBILITY...BUT WITH DECREASING INSTABILITIES...DO EXPECT A
GENERAL WEAKENING TREND TO ANY THUNDERSTORMS THAT DO MAKE IT INTO
OUR FA.
&&
.SHORT TERM /6 AM WEDNESDAY MORNING THROUGH THURSDAY NIGHT/...
COLD FRONT IS BEING PROGGED WITH A CONTINUOUSLY FASTER SOLUTION
WITH EACH MODEL RUN. IN THE NW CWA AT 12Z IT IS WELL SOUTHEAST OF
THE I-71 CORRIDOR BY 18Z. PRECIP IN THE COLD POOL BEHIND THE WIND
SHIFT WILL BE HARD PRESSED TO SEE DAMAGING WINDS WITH ANY
CONVECTIVE ELEMENTS AND THE SWODY2 OUTLOOK APPEARS TO WHITTLE AWAY
AT THE SEVERE PROSPECTS WITH EACH DISCUSSION. AT THIS MOMENT...I
WOULD EXPECT A RAINY PERIOD WITH THUNDER BUT THE LACK OF DISTINCT
STRONG CORES/UPDRAFTS NECESSARY FOR WIND/HAIL. ELEVATED
INSTABILITY WILL MAKE FOR OCCASIONAL DOWNPOURS AND WINDS WHEN
THESE ELEVATED CORES COLLAPSE...BUT THE EXPECTED HIGH MOISTURE AND
COLD NATURE OF THE AIR IN THE BOUNDARY LAYER WOULD LIMIT ANY VERY
STRONG WINDS FROM OCCURRING.
HIGHS WERE PROGGED TO BE A BIT WARMER THAN I WOULD EXPECT IN THE
SOUTHEAST WITH A GRUNGY DAY OF CLOUD COVER. LOWERED READINGS A BIT
TO TOP OUT AT 90 DEGREES AS A MAXIMUM AND THINK THAT THIS WOULD BE
AN EARLY AFTERNOON HIGH WITH STRONG ADVECTION FROM A SUNNY POCKET
OVER KY BEING PULLED INTO MY NRN KY AND SERN OH COUNTIES. NW CWA
WILL BE THOROUGHLY GRUNGED AND NOT REACH PAST THE 70S.
AFTER PRECIP ENDS TOMORROW NIGHT...HIGH PRESSURE WILL PUSH IN
DRIER AND COOLER AIR TO THE OHIO VALLEY AND THIS WILL REMAIN IN
PLACE THROUGH THE END OF THE WORK WEEK.
&&
.LONG TERM /FRIDAY THROUGH TUESDAY/...
SURFACE HIGH PRESSURE WILL BE CENTERED ACROSS THE OHIO VALLEY ON
FRIDAY. THIS HIGH WILL QUICKLY SLIDE SOUTHEAST OF OUR REGION AND
WEAKEN AS AN UPPER LEVEL DISTURBANCE EMBEDDED IN NORTHWESTERLY
FLOW APPROACHES OUR REGION. MODELS HAVE ACCELERATED THE ARRIVAL OF
THIS DISTURBANCE...YET STILL VARY BY SEVERAL HOURS ON THEIR
FORECAST ARRIVAL OF PRECIPITATION ON SATURDAY. ADDED LOW CHANCE
POPS EARLY SATURDAY MORNING WITH POPS RAMPING UP INTO THE DAY
SATURDAY BASED ON THE FASTER TREND. KEPT ONLY CHANCE POPS ON
SATURDAY DUE TO TIMING AND COVERAGE UNCERTAINTIES FOR
PRECIPITATION ON SATURDAY. TEMPERATURES UNDER THE HIGH ON FRIDAY
WILL REMAIN A FEW DEGREES BELOW NORMAL. ONCE THE HIGH SHIFTS TO
OUR SOUTHEAST...A REBOUND TO NEAR NORMAL TEMPERATURES CAN BE
EXPECTED FOR SATURDAY.
ON SUNDAY...A UNSEASONABLY DEEP TROUGH IS EXPECTED TO DIG
SOUTHEASTWARD ACROSS THE MID WEST AND INTO THE OHIO VALLEY. LOW
PRESSURE DOWNSTREAM OF THIS TROUGH WILL DRAG A COLD FRONT ACROSS OUR
AREA. THE CMC AND GFS ARE IN FAIRLY GOOD AGREEMENT ON BRINGING
ENHANCED CHANCES FOR PRECIPITATION TO OUR AREA ON SUNDAY AHEAD OF
THIS FRONT...WITH THE COLD FRONT CROSSING OUR AREA AT SOME POINT
LATE SUNDAY. BEST CHANCES FOR PRECIPITATION APPEAR TO BE DURING THE
DAY SUNDAY IN THE WARM SECTOR...WITH COOLER AIR MOVING INTO THE
REGION BY MONDAY. THE TROUGH IS FORECAST TO REMAIN IN THE REGION
THROUGH THE EARLY PARTS OF NEXT WEEK. MODELS VARY ON HOW MUCH
MOISTURE LINGERS BEHIND THE FRONT. AM FORECASTING MAINLY LOW CHANCE
DIURNALLY DRIVEN SHOWERS AND ISOLATED THUNDERSTORMS IN THE COLD
SECTOR. THIS HIGH AMPLITUDE TROUGH WILL BRING ANOTHER ROUND OF WELL
BELOW NORMAL TEMPERATURES TO THE OHIO VALLEY EARLY NEXT WEEK...WITH
CURRENT INDICATIONS BEING THAT HIGHS MAY ONLY REACH THE LOWER 70S ON
MONDAY AND POSSIBLY AGAIN ON TUESDAY.
&&
.AVIATION /01Z WEDNESDAY THROUGH SUNDAY/...
DIURNAL CU WILL CONTINUE TO DISSIPATE THROUGH MID EVENING..LEAVING
MAINLY CLEAR SKIES HEADING INTO THE OVERNIGHT HOURS. A COLD FRONT
WILL DROP DOWN FROM THE NORTHWEST LATE TONIGHT AND PUSH ACROSS THE
TAF SITES LATER WEDNESDAY MORNING INTO EARLY AFTERNOON. CONVECTION
CURRENTLY ASSOCIATED WITH THE FRONT IS STILL WELL OFF TO OUR
NORTHWEST. THIS WILL SAG SOUTHEAST TOWARD OUR AREA TONIGHT WITH
SOME OF THE HI RES CONVECTIVE MODELS SUGGESTING SOME OF IT WILL
HOLD TOGETHER AS IT WORKS INTO OUR NORTHWEST LATE TONIGHT.
HOWEVER...INSTABILITY WILL BE DECREASING THROUGH THE OVERNIGHT
HOURS...SO WOULD EXPECT TO SEE A WEAKENING/DISSIPATING TREND IF IT
DOES MAKE IT ALL THE WAY DOWN INTO OUR AREA. WILL THEREFORE ALLOW
FOR SOME INCREASING MID/HIGH LEVEL CLOUDS LATE TONIGHT AND THEN
GENERALLY COVER THE INITIAL THUNDERSTORM THREAT WITH JUST A VCTS.
MORE WIDESPREAD THUNDERSTORM ACTIVITY SHOULD THEN FIRE UP ALONG
THE FRONT AS WE DESTABILIZE HEADING INTO WEDNESDAY AFTERNOON. THE
BEST CHANCE FOR THIS WILL BE JUST SOUTHEAST OF THE I-71 CORRIDOR
AND GENERALLY SOUTHEAST OF THE TAF SITES. AS A RESULT...WILL JUST
HAVE A P6SM -SHRA AND VCTS INTO EARLY TO MID AFTERNOON FOR THE TAF
SITES ALONG THE I-71 CORRIDOR.
OUTLOOK...THUNDERSTORMS POSSIBLE SATURDAY AND SUNDAY.
&&
.ILN WATCHES/WARNINGS/ADVISORIES...
OH...NONE.
KY...NONE.
IN...NONE.
&&
$$
SYNOPSIS...FRANKS
NEAR TERM...JGL
SHORT TERM...FRANKS
LONG TERM...LATTO
AVIATION...JGL
AREA FORECAST DISCUSSION
NWS TULSA OK
921 PM CDT TUE JUL 22 2014
...UPDATE...
.DISCUSSION...
TEMPS IN THE UPPER 70S TO UPPER 80S REMAINED COMMON ACROSS EASTERN
OKLAHOMA AND NORTHWEST ARKANSAS THIS EVENING. HEAT INDICES HAVE
ALSO COME DOWN SOME WITH VALUES IN THE RANGE FORM THE MID 80S TO
MID 90S STILL BEING REPORTED OVER NORTHEAST OKLAHOMA. TO THE NORTH
OF THE CWA...A WEAK COLD FRONT REMAINED POSITIONED ACROSS NORTHERN
KANSAS AND NORTHERN MISSOURI. THIS FRONT IS EXPECTED TO SAG
SOUTHWARD OVERNIGHT AND MOVE INTO THE FAR NORTHERN PART OF THE CWA
WEDNESDAY MORNING. LATEST RUNS OF THE LOCAL IN-HOUSE MODEL AS
WELL AS THE HRRR TRY TO DEVELOP THUNDERSTORMS ALONG/AHEAD OF THE
FRONT AND PUSH THEM INTO NORTHEAST OKLAHOMA AND NORTHWEST ARKANSAS
ALONG AN OUTFLOW BOUNDARY LATE TONIGHT. THE HRRR RUNS SAYS THAT
THERE SHOULD ALREADY BE ONGOING CONVECTION ACROSS CENTRAL
KANSAS...THROUGH LOOKING AT LATEST SATELLITE DATA...THERE SEEMS BE
LITTLE IN THE WAY OF CLOUD COVER. THE CAP OVER THE REGION LOOKS TO
BE NOT QUITE AS STRONG COMPARED TO OVER KANSAS THIS EVENING AND
THIS COULD ALLOW FOR SOME THUNDERSTORM ACTIVITY LATE TONIGHT TO
DEVELOP AND MOVE INTO THE CWA. THUS...WILL KEEP A SLIGHT CHANCE
POP OVER PARTS OF NORTHEAST OKLAHOMA INTO NORTHWEST ARKANSAS LATE
TONIGHT. THE BETTER CHANCES LOOK TO BE DURING THE DAY WEDNESDAY AS
THE FRONT ENTERS THE CWA AND INTERACTS WITH DAYTIME
HEATING/INSTABILITY. EVENING UPDATE WILL BE TO TWEAK POPS/WX A BIT
OTHERWISE THE REST OF THE FORECAST SEEMS TO BE HANDLING WELL.
EVEN WITH THE WEAK FRONT MOVING THROUGH THE REGION...HOT AND HUMID
CONDITIONS STILL LOOK POSSIBLE OVER THE REGION...ESPECIALLY SOUTH
OF THE BOUNDARY. WILL KEEP THE CURRENT HEAT HEADLINES AS IS.
&&
.PRELIMINARY POINT TEMPS/POPS...
TUL 76 98 72 94 / 10 30 10 0
FSM 73 96 72 93 / 20 50 20 10
MLC 71 95 72 96 / 10 20 20 10
BVO 71 95 68 94 / 10 30 10 0
FYV 68 90 67 88 / 20 50 20 10
BYV 69 90 65 86 / 20 50 10 10
MKO 72 96 71 94 / 20 30 10 10
MIO 72 92 68 91 / 20 50 10 10
F10 73 96 72 94 / 10 20 10 10
HHW 71 95 74 96 / 10 10 20 10
&&
.TSA WATCHES/WARNINGS/ADVISORIES...
OK...EXCESSIVE HEAT WARNING UNTIL 8 PM WEDNESDAY FOR OKZ060.
HEAT ADVISORY FROM 1 PM WEDNESDAY TO 8 PM WEDNESDAY FOR OKZ054-
OKZ055-OKZ056-OKZ059-OKZ061-OKZ062-OKZ064-OKZ065-OKZ066-
OKZ067-OKZ068-OKZ070-OKZ071-OKZ072-OKZ074.
AR...NONE.
&&
$$
SHORT TERM...20
AVIATION.....07
AREA FORECAST DISCUSSION
NWS PORTLAND OR
847 PM PDT TUE JUL 22 2014
.SYNOPSIS...A LOW PRESSURE SYSTEM WILL BRING AN INCREASING THREAT
OF RAIN SHOWERS AND THUNDERSTORMS TO THE AREA TONIGHT AND
ESPECIALLY WEDNESDAY. AFTER A CLOUDY AND WET START TO
WEDNESDAY...EXPECT A MIX OF SUNSHINE AND SHOWERS IN THE AFTERNOON.
DRIER AND MORE SUMMER-LIKE TEMPERATURES ARE EXPECTED TO ARRIVE LATE
THURSDAY AND FRIDAY...BEFORE TEMPERATURES PUSH 90F LATE IN THE
WEEKEND.
&&
.UPDATE...SCATTERED THUNDERSTORMS HAVE DEVELOPED OVER THE LANE COUNTY
CASCADES LATE THIS AFTERNOON. ONE STORM WAS PARTICULARLY STRONG AND
SEVERAL SEVER THUNDERSTORMS WERE ISSUED FOR IT AS IT MOVED ACROSS THE
LANE COUNTY CASCADES AND CASCADE FOOTHILLS. THESE THUNDERSTORMS THERE
ARE PLENTY OF THUNDERSTORMS JUST EAST OF THE CASCADES...WHICH AN
ISOLATED CELL MAY SKIRT WEST OF THE CASCADES AT TIMES THIS EVENING.
THE THUNDERSTORMS SEEM TO BE WEAKENING DUE TO THE LOSS OF SOLAR
HEATING...BUT THE THREAT WILL INCREASE AGAIN LATE TONIGHT INTO WED
MORNING AS A STRONG AND COOL UPPER LEVEL LOW BEGINS TO MOVE INLAND.
.PREVIOUS DISCUSSION FOLLOWS...THIS EVENING...A VORT MAX...APPARENT
IN WATER VAPOR SATELLITE IMAGERY...NEAR THE BAY AREA WILL LIFT
NORTHEASTWARD THIS AFTERNOON AND EVENING INTO SOUTH CENTRAL OREGON.
VISIBLE SATELLITE IMAGERY SHOWS FAIRLY EXTENSIVE CLOUD COVER OVER THE
EASTERN HALF OF THE FORECAST AREA WITH A FEW BREAKS CREEPING INTO THE
CASCADES. A DESTABILIZING LOWER ATMOSPHERE AND LIFT AHEAD OF THE
AFOREMENTIONED VORT MAX SHOULD ALLOW THUNDERSTORMS TO DEVELOP ACROSS
SOUTH CENTRAL OREGON THIS AFTERNOON. IN FACT...CONVECTION IS
BEGINNING TO FIRE EAST OF THE CENTRAL OREGON CASCADES NEAR BEND. WITH
ADDITIONAL HEATING THIS AFTERNOON...EXPECT SOME OF THIS CONVECTION TO
BEGIN DEVELOPING JUST TO THE WEST OF THE CREST...BUT THERE STILL
REMAINS UNCERTAINTY IN HOW MUCH...IF ANY...WILL DEVELOP. THE LATEST
RAP GUIDANCE SUGGESTS A FEW THUNDERSTORMS WILL BE POSSIBLE LATE THIS
AFTERNOON OVER THE LANE AND LINN COUNTY CASCADES...BUT IF THE CURRENT
MID LEVEL CLOUDS LINGER TOO MUCH LONGER THIS AFTERNOON...SURFACE
BASED CONVECTION WILL LIKELY STAY ENTIRELY EAST OF OUR FORECAST AREA.
THE LATEST HRRR SUPPORTS THE LATTER IDEA. IT SHOULD BE NOTED THAT IF
ANY STORMS DO BREAK THE CAP ON OUR SIDE OF THE CREST...40-45 KT OF
0-6KM BULK SHEAR AND CAPE VALUES BETWEEN 500-750 J/KG WILL AID STORM
ORGANIZATION. FREQUENT LIGHTNING...AND POSSIBLY MARGINALLY SEVERE
HAIL AND DAMAGING WINDS WOULD BE THE PRIMARY THREATS OF CONCERN IF
STORMS WERE TO MATERIALIZE. AGAIN...THE MOST LIKELY AREA TO
EXPERIENCE SUCH STORMS IS PRIMARILY NEAR THE CASCADE CREST...SOUTH OF
MOUNT JEFFERSON.
FOR TONIGHT...THE LARGE SHORTWAVE TROUGH CURRENTLY NEAR 135W...DUE
WEST OF OREGON...WILL ELONGATE FURTHER TONIGHT...TURNING THE MID
LEVEL FLOW OVER NORTHWEST OREGON SLIGHTLY MORE SOUTHERLY. THE NAM
BRINGS A PIECE OF THE VORT MAX/PV ANOMALY NEAR 130W AND 35N ACROSS
THE AREA LATE TONIGHT. WITH NEGATIVE THETAE LAPSE RATES BETWEEN
700-500MB ADVECTING INTO THE REGION...AND REGION BEING IN THE RIGHT
ENTRANCE/LEFT EXIT REGION OF TWO UPPER LEVEL JETS...WE MAY SEE
SHOWERS AND EVEN A FEW ELEVATED THUNDERSTORMS SPREAD NORTHWARD ACROSS
WESTERN OREGON LATE TONIGHT. HOWEVER...CONFIDENCE IS LOW SO THE
THUNDER MENTION WAS LIMITED TO A SLIGHT CHANCE. THE LATEST HRRR
KEEPS THE BULK OF THE ACTIVITY RIGHT ALONG THE CASCADE CREST AND
POINTS EAST...BUT GIVEN THE PATTERN WILL KEEP THE MENTION IN THE
FORECAST.
THE PREVIOUSLY MENTIONED ELONGATING SHORTWAVE TROUGH NEAR 135W WILL
BEGIN TO PUSH EAST-NORTHEASTWARD ACROSS THE AREA WEDNESDAY. STRONG
MID LEVEL FRONTOGENESIS SHOULD LEAD TO A FAIRLY ORGANIZED NORTH-SOUTH
ORIENTED BAND OF RAIN MOVING EASTWARD INTO THE OREGON COAST WEDNESDAY
MORNING. SOME MODEST MID LEVEL INSTABILITY COUPLED WITH THE DYNAMICS
MAY LEAD TO A FEW LIGHTNING STRIKES ALONG THE FRONT...PARTICULARLY
OVER THE COASTAL WATERS AND NEAR THE COAST LATE TONIGHT INTO
WEDNESDAY MORNING.
THE BAND OF RAIN SHOULD PUSH EASTWARD ACROSS THE AREA WEDNESDAY
MORNING. SUBSIDENCE BEHIND THE MID LEVEL FRONT MAY LEAD TO A RATHER
ABRUPT END TO THE RAIN/CLOUDS EARLY TO MID WEDNESDAY AFTERNOON.
HOWEVER...ANY CLEARING WILL NOT LAST LONG...AS THE LOWER ATMOSPHERE
SHOULD DESTABILIZE QUICKLY...AND A SPRING-LIKE PATTERN OF SCATTERED
SHOWERS AND ISOLATED THUNDERSTORMS WILL LIKELY ENSUE LATE WEDNESDAY
AFTERNOON AND EARLY EVENING. THE GREATEST INSTABILITY WILL BE OVER
THE NORTHERN HALF OF THE FORECAST AREA SO THE MENTION OF THUNDER WAS
INCREASED TO CHANCE WORDING.
WITH A SURFACE LOW PRESSURE LINGERING JUST OFF THE SOUTHWEST
WASHINGTON COAST WEDNESDAY THERE MAY BE A TENDENCY FOR SURFACE WINDS
IN THE WILLAMETTE VALLEY AND ALONG THE LOWER COLUMBIA RIVER TO HAVE A
BIT MORE OF A S TO SSE COMPONENT THAN OTHERWISE EXPECTED. COMBINED
WITH WSW WINDS OF 25 KT AT 900MB AND 40KT AT 500MB...A RAPIDLY
STRENGTHENING UPDRAFT COULD ROTATE BRIEFLY. HOWEVER...CONFIDENCE IS
VERY LOW IN THIS ACTUALLY OCCURRING SOMEWHERE WITHIN THE CWA...BUT
IT WILL STILL BE WORTH MONITORING. THE MORE EXPECTED HAZARDS...
GUSTY WINDS AND SMALL HAIL WERE ADDED TO THE THUNDER WORDING IN THE
GRIDS.
ON THE FIRE FRONT...MOST LOCATIONS ACROSS THE FORECAST AREA SHOULD
SEE WETTING RAINS OF A QUARTER TO HALF INCH WITH A FEW LOCATIONS
LIKELY PUSHING AN INCH OF RAIN...PARTICULARLY ACROSS SOUTHWEST
WASHINGTON. IT SHOULD BE NOTED WETTING RAINS ARE LESS LIKELY TOWARDS
LANE COUNTY...BUT CERTAINLY APPEAR POSSIBLE WEDNESDAY.
EXPECT A DRYING TREND WEDNESDAY NIGHT INTO THURSDAY BEFORE MORE
SEASONABLE WEATHER RETURNS FRIDAY. /NEUMAN
.LONG TERM...HIGH PRESSURE WILL BUILD WESTWARD ACROSS THE CONUS
AMPLIFYING AN UPPER-LEVEL RIDGE THAT WILL SET UP OVER THE
NORTHWESTERN U.S. THIS WILL INCREASE TEMPERATURES BACK TO ABOVE
NORMAL OVER THE WEEKEND. THERE IS A POSSIBLE DISTURBANCE THAT COULD
MOVE THROUGH AS EARLY AS SUNDAY NIGHT...BUT MUCH UNCERTAINTY EXISTS
IN THE TIMING OF THIS SYSTEM AND LOCATION. -MCCOY
&&
.AVIATION...VFR CONDITIONS PREVAIL THIS EVENING. EXPECT INCREASING
CLOUDS AND RAIN AS AN APPROACHING LOW PRESSURE SYSTEM MOVES INTO
THE AREA STARTING AROUND 10Z WED. EXPECT CIGS TO LOWER AFT 12Z...
WITH MVFR CIGS AROUND 2000 FT POSSIBLE. LOCAL POCKETS OF IFR
POSSIBLE IN HEAVIER RAIN...AND ALONG THE COAST. HIGHER TERRAIN AND
MOUNTAINS OBSCURED TONIGHT THROUGH MID MORNING WED. THUNDERSTORMS
OVER THE HIGHER TERRAIN WILL CONTINUE THROUGH EARLY TONIGHT...THEN
EXPECT A WIDESPREAD THREAT FOR THUNDERSTORMS ACROSS THE REGION
EARLY WED MORNING THROUGH WED EVENING.
KPDX AND APPROACHES...EXPECT VFR TO CONTINUE THROUGH THIS EVENING
WITH SCATTERED CLOUDS AROUND 3000 FT AND AN OVERCAST DECK ABOVE
5000 FT. EXPECT RAIN TO INCREASE AFT 12Z WITH CIGS LOWERING TO
LOW VFR TO HIGHER MVFR. 20 PERCENT CHANCE OF THUNDERSTORMS
IMPACTING KPDX AND APPROACHES MAINLY AFTER 12Z WED AND CONTINUING
THROUGH WED EVENING. CULLEN/27
&&
.MARINE...RELATIVELY QUIET CONDITIONS OVER THE WATERS CONTINUE
TONIGHT AS THE SURFACE GRADIENT REMAINS WEAK IN BETWEEN
SYSTEMS...KEEPING WINDS 15 KT OR LESS. SEAS REMAIN 3-4 FT TONIGHT
WITH A CONTINUED SMALL W-NW SWELL.
A LOW PRES SYSTEM WILL PASS THROUGH THE WATERS LATE TONIGHT INTO
WED. MODELS HAVE TRENDED TO INDICATE THE POTENTIAL FOR MARGINAL
SMALL CRAFT WINDS WEDNESDAY AFTERNOON...BOTH S WINDS ALONG THE
COASTAL INNER WATERS AND ALSO OVER MUCH OF THE WATERS AS THE
SURFACE LOW PUSHES ACROSS. CONFIDENCE REMAINS SOMEWHAT LOW AT THIS
TIME HOWEVER SO WILL LET NEXT SHIFT EVALUATE NEXT MODEL CYCLE
BEFORE POTENTIALLY RAISING THE SMALL CRAFT ADVISORY. LATER THIS
WEEK...HIGH PRES REDEVELOPS OVER NE PAC AS THERMAL LOW PRES BUILDS
OVER N CALIFORNIA. THIS WILL BRING A RETURN TO GUSTY N WINDS AND
STEEP WIND DRIVEN SEAS...PARTICULARLY IN THE LATE AFTERNOON AND
EVENING HOURS...FRI THROUGH THE WEEKEND. CULLEN
&&
.PQR WATCHES/WARNINGS/ADVISORIES...
OR...WA...NONE.
PZ...NONE.
&&
$$
MORE WEATHER INFORMATION ONLINE AT...HTTP://WEATHER.GOV/PORTLAND
INTERACT WITH US VIA SOCIAL MEDIA
WWW.FACEBOOK.COM/US.NATIONALWEATHERSERVICE.PORTLAND.GOV
WWW.TWITTER.COM/NWSPORTLAND
THIS DISCUSSION IS FOR NORTHWEST OREGON AND SOUTHWEST WASHINGTON
FROM THE CASCADE CREST TO 60 NAUTICAL MILES OFFSHORE. THE AREA IS
COMMONLY REFERRED TO AS THE FORECAST AREA.
COMMONLY REFERRED TO AS THE FORECAST AREA.
AREA FORECAST DISCUSSION...UPDATED
NWS PORTLAND OR
638 AM PDT MON JUL 21 2014
UPDATED FOR POPS ADDED TODAY
.SYNOPSIS...A LARGE SCALE UPPER TROUGH REMAINS OVER THE NORTHEAST
PACIFIC THROUGH MID WEEK MAINTAINING COOLER ONSHORE FLOW. A FAIRLY
STRONG UPPER LOW WILL SET UP OFF THE PACIFIC NORTHWEST COAST TUESDAY
AND WEDNESDAY WITH AN INCREASING THREAT OF SHOWERS OVER THE AREA. A
FEW THUNDERSTORMS ARE POSSIBLE MAINLY NEAR THE CASCADES TUESDAY AND
OVER SOUTHWEST WASHINGTON AND FAR NORTHWEST OREGON ON WEDNESDAY.
WEDNESDAY WILL BE THE COOLEST DAY OF THIS WEEK. DRIER AND WARMER
WEATHER IS EXPECTED LATE IN THE WEEK AND NEXT WEEKEND.
&&
.UPDATE...THE SAME HRRR RUNS THAT HAVE BEEN THE ONLY MODEL(S) TO
SHOW THE SPRINKLES OVER THE NORTH COAST ALSO SHOWED SOME LIGHT
FORECASTED RADAR RETURNS FROM THE SOUTHWEST FLOW BEGINNING AROUND
18Z TODAY. REALITY HAS BROUGHT ECHOS STREAMING INLAND FROM OFF THE
SOUTH OREGON COAST. THE HRRR SHOWS A SHORT WAVE SLIDING ALONG THIS
DEFORMATION BAND/STALLED FRONT THROUGH THE END OF ITS RUN THROUGH AT
LEAST 01Z. HAVE DECIDED TO ADD AN ISOLATED SHOWER MENTION BASICALLY
COVERING THE SOUTHEAST 1/4 OF THE CWA SOUTH OF A LINE FROM ROUGHLY
FLORENCE TO MT JEFFERSON. DO NOT EXPECT ANY SIGNIFICANT RAIN AMOUNTS
TO FALL BUT COULDN`T IGNORE THE POTENTIAL FOR AT LEAST SOME ACTIVITY
TO BASICALLY CONNECT THE RAIN DROPS ON THE GROUND. /JBONK
&&
.PREV DISC... /ISSUED 417 AM PDT MON JUL 21 2014/
SHORT TERM...TODAY THROUGH WEDNESDAY NIGHT...THE STRATUS DECK HAS
LARGELY LIFTED AND BROKEN UP QUITE A BIT. A SOUTHWESTERLY FETCH OF
MID AND UPPER LEVEL MOISTURE IS PASSING OVERHEAD AS THE UPPER TROUGH
CONTINUES TO DIG OFFSHORE. THIS LEAVES THE PACNW UNDER A VERY
COMPLICATED FLOW PATTERN AS THE RIDGE TO THE SOUTH PUSHES UP
MOISTURE ACROSS SOUTH CENTRAL AND SOUTHEAST OREGON WHILE THE UPPER
TROUGH PICKS UP ON PACIFIC MOISTURE. AM CURRENTLY SEEING A
SMATTERING OF VERY LIGHT SHOWER ACTIVITY JUST OFF OF AND ALONG THE
COAST SO HAVE OPTED TO INCLUDE SPRINKLE WORDING THROUGH EARLY
AFTERNOON. THE 06Z HRRR IS THE ONLY MODEL TO HAVE PICKED UP ON THIS.
THE UPPER LOW ALONG THE NORTH B.C. COAST WILL CONTINUE MOVING SOUTH
TODAY AND SET UP ALONG THE PACIFIC NORTHWEST COAST TUESDAY. AS IT
DOES THE SOUTHWESTERLY MOISTURE FETCH IS FORECAST TO FURTHER SPREAD
IN OVER OUR FORECAST AREA LATER TODAY AND TONIGHT POSSIBLY LEADING
TO SHOWERS OR CASCADE THUNDERSTORMS THROUGH TUESDAY. MODEL DETAILS
AND TIMING OF PRECIPITATION HAVE BEEN VARYING CONSIDERABLY WITH THE
ECMWF/GEM WETTER...SO EXACT TIMING OF WHEN THE THREAT INCREASES IS A
BIT UNCERTAIN. NEVERTHELESS...BY TUESDAY THERE SHOULD BE A FEW
SHOWERS AROUND.
THE UPPER LOW CONTINUES TO SAG SOUTH THEN STARTS TO SWING ONSHORE
TUESDAY NIGHT AND WEDNESDAY. IT APPEARS THERE IS A FRONTAL ZONE
ASSOCIATED WITH THIS LOW THAT MAY INTERACT WITH THE MOISTURE THAT IS
ALREADY OVER OUR AREA FROM TUESDAY AS IT SPREADS ONSHORE TUESDAY
NIGHT. THE MODEL TIMING OF THE UPPER LOW IS A BIT SLOWER THAN MODEL
RUNS SHOWED 24 OR 48 HOURS AGO...MOVING EAST OF OUR FORECAST AREA
WEDNESDAY NIGHT. THE WEDNESDAY INTO WEDNESDAY EVENING TIME FRAME
LOOKS TO BE THE WETTEST PERIOD FOR OUR AREA THIS WEEK. THE COLD POOL
STILL LOOKS LIKE IT WILL BRUSH THE NORTHERN PORTIONS OF OUR FORECAST
AREA WEDNESDAY INTO WEDNESDAY EVENING FOR A FEW THUNDERSTORMS.
WEDNESDAY LOOKS TO BE THE COOLEST DAY OF THE WEEK AS WELL.
JBONK/TOLLESON
LONG TERM...NO CHANGES. PREVIOUS DISCUSSION FOLLOWS...THURSDAY
THROUGH SUNDAY...THE UPPER LEVEL TROUGH DEPARTS THE REGION ON
THURSDAY. A FEW SHOWERS MAY LINGER INTO THURSDAY OVER THE NORTHERN
MOUNTAINS. DRY AND SEASONABLE WEATHER WILL RETURN FRIDAY THROUGH
NEXT WEEKEND. TW
AVIATION...MAINLY VFR CONDITIONS ACROSS THE AREA WITH A SCT TO BKN
LAYER AROUND 5000 FT AND HIGHER CIRRUS ABOVE. COASTAL AREAS MAY SEE
SOME PATCHY FOG ALONG WITH MVFR CIGS AROUND 1000-1500 FT THIS
MORNING. MVFR CONDITIONS APPEAR UNLIKELY AT THIS POINT IN THE
INTERIOR TAFS SITES TODAY AND TONIGHT.
KPDX AND APPROACHES...EXPECT MAINLY VFR CONDITIONS THROUGH 12Z
TUESDAY. THERE IS A 20 PERCENT CHANCE MVFR STRATUS WILL IMPACT THE
TERMINAL PRIMARILY BETWEEN 14Z AND 17Z MONDAY.
MARINE...RELATIVELY BENIGN WIND AND SEA CONDITIONS FOR MUCH OF THE
WEEK. SEAS WILL AROUND 7 FT TODAY WILL DROP TO THE 3 TO 5 FT RANGE
TONIGHT AND FOR MUCH OF THE WEEK. A WEAK LOW PRESSURE WILL PASS
THROUGH THE WATERS TUESDAY INTO WEDNESDAY...BUT IS EXPECTED TO HAVE
VERY LITTLE IMPACT. WITH HIGH PRESSURE REDEVELOPING OVER THE
NORTHEAST PACIFIC AND THERMAL LOW PRESSURE STRENGTHENING OVER
NORTHERN CALIFORNIA LATE IN THE WORK WEEK...EXPECT GUSTY NORTHERLY
WINDS AND STEEP WIND DRIVEN SEAS TO RETURN. /NEUMAN/26
&&
.PQR WATCHES/WARNINGS/ADVISORIES...
OR...WA...NONE.
PZ...NONE.
&&
$$
MORE WEATHER INFORMATION ONLINE AT...HTTP://WEATHER.GOV/PORTLAND
INTERACT WITH US VIA SOCIAL MEDIA
WWW.FACEBOOK.COM/US.NATIONALWEATHERSERVICE.PORTLAND.GOV
WWW.TWITTER.COM/NWSPORTLAND
THIS DISCUSSION IS FOR NORTHWEST OREGON AND SOUTHWEST WASHINGTON
FROM THE CASCADE CREST TO 60 NAUTICAL MILES OFFSHORE. THE AREA IS
COMMONLY REFERRED TO AS THE FORECAST AREA.
AREA FORECAST DISCUSSION
NWS PORTLAND OR
417 AM PDT MON JUL 21 2014
.SYNOPSIS...A LARGE SCALE UPPER TROUGH REMAINS OVER THE NORTHEAST
PACIFIC THROUGH MID WEEK MAINTAINING COOLER ONSHORE FLOW. A FAIRLY
STRONG UPPER LOW WILL SET UP OFF THE PACIFIC NORTHWEST COAST TUESDAY
AND WEDNESDAY WITH AN INCREASING THREAT OF SHOWERS OVER THE AREA. A
FEW THUNDERSTORMS ARE POSSIBLE MAINLY NEAR THE CASCADES TUESDAY AND
OVER SOUTHWEST WASHINGTON AND FAR NORTHWEST OREGON ON WEDNESDAY.
WEDNESDAY WILL BE THE COOLEST DAY OF THIS WEEK. DRIER AND WARMER
WEATHER IS EXPECTED LATE IN THE WEEK AND NEXT WEEKEND.
&&
.SHORT TERM...TODAY THROUGH WEDNESDAY NIGHT...THE STRATUS DECK HAS
LARGELY LIFTED AND BROKEN UP QUITE A BIT. A SOUTHWESTERLY FETCH OF
MID AND UPPER LEVEL MOISTURE IS PASSING OVERHEAD AS THE UPPER TROUGH
CONTINUES TO DIG OFFSHORE. THIS LEAVES THE PACNW UNDER A VERY
COMPLICATED FLOW PATTERN AS THE RIDGE TO THE SOUTH PUSHES UP
MOISTURE ACROSS SOUTH CENTRAL AND SOUTHEAST OREGON WHILE THE UPPER
TROUGH PICKS UP ON PACIFIC MOISTURE. AM CURRENTLY SEEING A
SMATTERING OF VERY LIGHT SHOWER ACTIVITY JUST OFF OF AND ALONG THE
COAST SO HAVE OPTED TO INCLUDE SPRINKLE WORDING THROUGH EARLY
AFTERNOON. THE 06Z HRRR IS THE ONLY MODEL TO HAVE PICKED UP ON THIS.
THE UPPER LOW ALONG THE NORTH B.C. COAST WILL CONTINUE MOVING SOUTH
TODAY AND SET UP ALONG THE PACIFIC NORTHWEST COAST TUESDAY. AS IT
DOES THE SOUTHWESTERLY MOISTURE FETCH IS FORECAST TO FURTHER SPREAD
IN OVER OUR FORECAST AREA LATER TODAY AND TONIGHT POSSIBLY LEADING
TO SHOWERS OR CASCADE THUNDERSTORMS THROUGH TUESDAY. MODEL DETAILS
AND TIMING OF PRECIPITATION HAVE BEEN VARYING CONSIDERABLY WITH THE
ECMWF/GEM WETTER...SO EXACT TIMING OF WHEN THE THREAT INCREASES IS A
BIT UNCERTAIN. NEVERTHELESS...BY TUESDAY THERE SHOULD BE A FEW
SHOWERS AROUND.
THE UPPER LOW CONTINUES TO SAG SOUTH THEN STARTS TO SWING ONSHORE
TUESDAY NIGHT AND WEDNESDAY. IT APPEARS THERE IS A FRONTAL ZONE
ASSOCIATED WITH THIS LOW THAT MAY INTERACT WITH THE MOISTURE THAT IS
ALREADY OVER OUR AREA FROM TUESDAY AS IT SPREADS ONSHORE TUESDAY
NIGHT. THE MODEL TIMING OF THE UPPER LOW IS A BIT SLOWER THAN MODEL
RUNS SHOWED 24 OR 48 HOURS AGO...MOVING EAST OF OUR FORECAST AREA
WEDNESDAY NIGHT. THE WEDNESDAY INTO WEDNESDAY EVENING TIME FRAME
LOOKS TO BE THE WETTEST PERIOD FOR OUR AREA THIS WEEK. THE COLD POOL
STILL LOOKS LIKE IT WILL BRUSH THE NORTHERN PORTIONS OF OUR FORECAST
AREA WEDNESDAY INTO WEDNESDAY EVENING FOR A FEW THUNDERSTORMS.
WEDNESDAY LOOKS TO BE THE COOLEST DAY OF THE WEEK AS WELL.
JBONK/TOLLESON
.LONG TERM...NO CHANGES. PREVIOUS DISCUSSION FOLLOWS...THURSDAY
THROUGH SUNDAY...THE UPPER LEVEL TROUGH DEPARTS THE REGION ON
THURSDAY. A FEW SHOWERS MAY LINGER INTO THURSDAY OVER THE NORTHERN
MOUNTAINS. DRY AND SEASONABLE WEATHER WILL RETURN FRIDAY THROUGH
NEXT WEEKEND. TW
&&
.AVIATION...MAINLY VFR CONDITIONS ACROSS THE AREA WITH A SCT TO BKN
LAYER AROUND 5000 FT AND HIGHER CIRRUS ABOVE. COASTAL AREAS MAY SEE
SOME PATCHY FOG ALONG WITH MVFR CIGS AROUND 1000-1500 FT THIS
MORNING. MVFR CONDITIONS APPEAR UNLIKELY AT THIS POINT IN THE
INTERIOR TAFS SITES TODAY AND TONIGHT.
KPDX AND APPROACHES...EXPECT MAINLY VFR CONDITIONS THROUGH 12Z
TUESDAY. THERE IS A 20 PERCENT CHANCE MVFR STRATUS WILL IMPACT THE
TERMINAL PRIMARILY BETWEEN 14Z AND 17Z MONDAY.
&&
.MARINE...RELATIVELY BENIGN WIND AND SEA CONDITIONS FOR MUCH OF THE
WEEK. SEAS WILL AROUND 7 FT TODAY WILL DROP TO THE 3 TO 5 FT RANGE
TONIGHT AND FOR MUCH OF THE WEEK. A WEAK LOW PRESSURE WILL PASS
THROUGH THE WATERS TUESDAY INTO WEDNESDAY...BUT IS EXPECTED TO HAVE
VERY LITTLE IMPACT. WITH HIGH PRESSURE REDEVELOPING OVER THE
NORTHEAST PACIFIC AND THERMAL LOW PRESSURE STRENGTHENING OVER
NORTHERN CALIFORNIA LATE IN THE WORK WEEK...EXPECT GUSTY NORTHERLY
WINDS AND STEEP WIND DRIVEN SEAS TO RETURN. /NEUMAN/26
&&
.PQR WATCHES/WARNINGS/ADVISORIES...
OR...WA...NONE.
PZ...NONE.
&&
$$
MORE WEATHER INFORMATION ONLINE AT...HTTP://WEATHER.GOV/PORTLAND
INTERACT WITH US VIA SOCIAL MEDIA
WWW.FACEBOOK.COM/US.NATIONALWEATHERSERVICE.PORTLAND.GOV
WWW.TWITTER.COM/NWSPORTLAND
THIS DISCUSSION IS FOR NORTHWEST OREGON AND SOUTHWEST WASHINGTON
FROM THE CASCADE CREST TO 60 NAUTICAL MILES OFFSHORE. THE AREA IS
COMMONLY REFERRED TO AS THE FORECAST AREA.
AREA FORECAST DISCUSSION...UPDATED
NWS ABERDEEN SD
644 PM CDT TUE JUL 22 2014
.UPDATE...
CONVECTION CONTINUES THIS EVENING ACROSS FAR WESTERN SD/ND
ASSOCIATED WITH A SHORTWAVE THAT IS RIDING THE UPPER RIDGE. LOOKS
LIKE THIS ACTIVITY WILL REMAIN WEST OF THIS CWA. THE 21Z RUC HAS A
GOOD HANDLE ON CURRENT EXTENT OF CONVECTION SO LEANED TOWARD THAT
SOLUTION. THEREFORE DECIDED TO LEAVE THE FORECAST PRECIP FREE
OVERNIGHT. FORECAST LOOKS GOOD OVERALL.
SEE UPDATED AVIATION DISCUSSION BELOW.
&&
.PREVIOUS DISCUSSION...
.SHORT TERM...TONIGHT THROUGH THURSDAY NIGHT
CANADIAN SURFACE HIGH PRESSURE BUILDING SLOWLY EAST WILL CONTINUE
TO BRING MAINLY DRY CONDITIONS...MOSTLY CLEAR SKIES AND SLIGHTLY
BELOW NORMAL TEMPERATURES THROUGH WEDNESDAY. THE MODELS SHOW THE
LARGE UPPER LEVEL HIGH PRESSURE AREA OVER THE SOUTHWEST US
REMAINING THROUGH THE SHORT TERM. A 50H RIDGE AXIS EXTENDING
NORTHWARD FROM THIS UPPER HIGH INTO CENTRAL CANADA WILL BE KNOCKED
DOWN BY A STRONG UPPER LEVEL LOW PRESSURE AREA MOVING IN FROM THE
PACIFIC NORTHWEST AND INTO SOUTHERN CANADA. SHORT WAVES COMING
OVER THE UPPER RIDGE FROM THE WEST AND ACROSS OUR REGION ALONG
WITH AN INCREASING LLJ WEDNESDAY NIGHT AND THURSDAY WILL BRING IN
CHANCES OF STORMS. FOR TONIGHT...SOME OF THE OPERATIONAL MODELS
AND HI-RES MODELS WERE SHOWING STORMS DEVELOPING IN THE HIGH
PLAINS LATE THIS AFTERNOON AND DROPPING SOUTHEAST ACROSS WESTERN
SD AND MAYBE INTO CENTRAL SD LATER THIS EVENING AND OVERNIGHT.
WILL LEAVE OUT POPS FOR NOW AS BELIEVE IT WILL REMAIN WEST OF OUR
CWA. OTHERWISE...WINDS WILL TURN SOUTHEAST INTO WEDNESDAY AND
INCREASE SOME. THE MODELS ALSO SHOW THE LLJ INCREASING INTO
WEDNESDAY NIGHT AND THURSDAY MORNING. WITH THIS FOCUS AND A RETURN
OF MOISTURE AND INSTABILITY...HAVE IN DECENT CHANCES OF STORMS
FOR WEDNESDAY NIGHT INTO THURSDAY. IT LOOKS LIKE IT WILL HEAT UP
AGAIN OUT WEST ON THURSDAY WITH HIGHS IN THE 90S ALONG AND WEST OF
THE RIVER. SOME PLACES WILL APPROACH 100 DEGREES AGAIN SOUTHWEST
OF PIERRE. WILL KEEP CHANCES OF STORMS GOING INTO THURSDAY NIGHT
AS A SURFACE FRONT MOVES IN FROM THE WEST.
.LONG TERM...FRIDAY THROUGH TUESDAY
MODELS CONTINUE TO SHOW A LARGE UPPER LOW DROPPING SOUTH INTO THE
GREAT LAKES REGION FOR THE LATTER HALF OF THE WEEKEND. THIS WILL
ALLOW A SHOT OF COOLER AIR TO DROP SOUTH OVER THE NORTHERN PLAINS
AND AFFECTING THE EASTERN DAKOTAS. AFTER A COUPLE WARM AND
SEASONABLE DAYS IN THE 80S FRIDAY AND SATURDAY...SUNDAY WILL SEE
HIGHS MORE THAN LIKELY DROP BACK INTO THE 70S FOR EASTERN PORTIONS
OF THE FORECAST AREA.
PRECIPITATION CHANCES A BIT MORE UNCLEAR IN THE EXTENDED PERIOD
WITH NO REAL SIGNIFICANT WAVES TO HANG YOUR HAT ON. GENERALLY
ACCEPTED ALLBLEND POP GRIDS AT THIS POINT.
&&
.AVIATION...
00Z TAFS FOR THE KABR...KATY...KPIR AND KMBG TERMINALS
VFR CONDITIONS WILL PERSIST THROUGH THE TAF FORECAST PERIOD.
TOWARDS 09Z WEDNESDAY THERE MAY BE A FEW ISOLD -SHRA/-TSRA OVER
WESTERN SD...POSSIBLY AS FAR EAST AS CENTRAL SD. OVERALL
CONFIDENCE IN EASTWARD EXTENT IS VERY LOW SO WILL LEAVE MENTION
OUT OF KMBG/KPIR TAFS AT THIS TIME.
&&
.ABR WATCHES/WARNINGS/ADVISORIES...
SD...NONE.
MN...NONE.
&&
$$
UPDATE...WISE
SHORT TERM...MOHR
LONG TERM...TMT
AVIATION...WISE
WEATHER.GOV/ABERDEEN
AREA FORECAST DISCUSSION...UPDATED
NWS MEMPHIS TN
948 PM CDT TUE JUL 22 2014
.UPDATE...
AN UPPER LEVEL LOW PRESSURE SYSTEM WAS LOCATED ALONG THE SOUTH AL
AND SOUTH MS BORDER THIS EVENING MOVING SLOWLY WESTWARD. SCATTERED
SHOWERS AND THUNDERSTORMS ASSOCIATED WITH THIS SYSTEM THAT SPREAD
INTO PORTIONS OF NORTH MS AND WEST TN EARLIER TODAY HAVE JUST
ABOUT DISSIPATED OR MOVED OUT OF THE REGION FOR THE NIGHT. LINGERING
SHOWERS AND THUNDERSTORMS ROTATING AROUND THIS LOW PRESSURE SYSTEM
WERE MOVING SOUTHWESTWARD OUT OF YALOBUSHA COUNTY IN NORTH MS AND
MAY CLIP THE SOUTHERN PORTIONS OF TALLAHATCHIE COUNTY. OTHERWISE
RAIN FREE WEATHER IS EXPECTED ACROSS MOST OF THE REGION THE
REMAINDER OF THE NIGHT. THE LATEST NAM AND HRRR MODELS CONTINUE TO
INDICATE THE POSSIBILITY OF A FEW SHOWERS AND THUNDERSTORMS MOVING
INTO PORTIONS OF NORTHEAST AR AND THE MO BOOTHEEL LATE TONIGHT
AHEAD OF A WEAK UPPER LEVEL SHORT WAVE EMBEDDED IN NORTHWEST FLOW
ALOFT...THIS IS ALREADY INDICATED IN THE EARLIER FORECAST.
SURFACE DEW POINTS HAVE REALLY INCREASED FROM RECENT DAYS AND ARE
PRESENTLY MAINLY IN THE LOWER AND MIDDLE 70S ACROSS MOST OF THE
AREA. THIS WILL MAKE FOR A WARMER NIGHT. ADDED PATCHY FOG WITH
DECREASING TEMPERATURE AND DEW POINT DEPRESSIONS ALONG WITH LIGHT
WINDS.
UPDATED GRIDS AND GRIDS WILL BE SENT SOON.
JCL
&&
.DISCUSSION... /ISSUED 345 PM CDT TUE JUL 22 2014/
CURRENTLY...A WEAK UPPER LOW LOCATED ALONG THE NORTHERN GULF
COAST IS RETROGRADING SLOWLY. MEANWHILE TO THE NORTH AN UPPER
RIDGE EXTENDS INTO THE MID MISSISSIPPI VALLEY. DEEPER MOISTURE
ASSOCIATED WITH THE UPPER LOW HAS MOVED INTO NORTH MISSISSIPPI AND
INTO AREAS NEAR THE TENNESSEE RIVER WHERE THE AIRMASS IS FAIRLY
UNSTABLE WITH SBCAPES AROUND 2500 J/KG. AS A RESULT ISOLD SHOWERS
AND THUNDERSTORMS HAVE DEVELOPED IN THOSE AFOREMENTIONED AREAS.
ELSW SKIES ARE PARTLY TO MOSTLY SUNNY. TEMPS RANGE FROM THE MID
80S AND NE MS TO AROUND 90 ELSW.
TONIGHT...THE UPPER LOW WILL CONTINUE TO RETROGRADE AND WEAKEN
OVERNIGHT. ISOLD SHOWERS AND THUNDERSTORMS ACROSS NE MISSISSIPPI AND
ALONG THE TN RIVER WILL DISSIPATE WITH LOSS OF HEATING EARLY THIS
EVENING. OTRW EXPECT A QUIET AND MILD NIGHT WITH TEMPS A FEW
DEGREES WARMER THAN LAST NIGHT SINCE SURFACE DEWPOINTS HAVE
INCREASED A BIT IN THE LAST 24 HOURS. LATER TONIGHT A COLD FRONT
WILL START TO MOVE INTO THE MIDDLE MISSISSIPPI VALLEY WHICH WILL
TRIGGER SHOWERS AND THUNDERSTORMS ACROSS MISSOURI. SOME OF THESE
COULD SNEAK INTO NE ARKANSAS BY MORNING SO ADDED A SMALL POP
THERE.
WEDNESDAY AND WEDNESDAY NIGHT...THE UPPER RIDGE BRIEFLY SNEAKS IN
AHEAD OF APPROACHING COLD FRONT ALLOWING FOR A WARM AND MUGGY DAY
FOR THE MIDSOUTH. MEANWHILE THE WEAK UPPER LOW ALONG THE NORTHERN
GULF COAST WILL PERSIST AND MAY HELP TRIGGER A FEW SHOWERS AND
THUNDERSTORMS ACROSS NORTH MISSISSIPPI. MORE IMPORTANTLY BY
AFTERNOON A COLD FRONT WILL BE APPROACHING NORTHERN AREAS OF THE
MIDSOUTH WITH CHANCES FOR SHOWERS AND THUNDERSTORMS. THE FRONT
WILL CONTINUE TO PUSH SOUTH THROUGH THE AREA WEDNESDAY NIGHT WITH
CHANCES FOR SHOWERS AND THUNDERSTORMS CONTINUING. THE AIRMASS WILL
BE QUITE UNSTABLE AHEAD OF THE FRONT AND SCATTERED SHOWERS AND
THUNDERSTORMS ARE EXPECTED WITH THE BEST CHANCES ACROSS THE
NORTHERN TIER. A FEW STRONG TO SEVERE STORMS ARE POSSIBLE WITH
DAMAGING WINDS THE MAIN THREAT WEDNESDAY AFTERNOON INTO WEDNESDAY
NIGHT. BY LATE WEDNESDAY NIGHT THE FRONT WILL BE LOCATED ACROSS
NORTHERN MISSISSIPPI AND COOLER/DRIER AIR WILL FILTER INTO
NORTHERN AREAS WITH TEMPS DROPPING INTO THE 60S.
THURSDAY THROUGH SATURDAY...THE COLD FRONT WILL EXIT NORTH
MISSISSIPPI IN THE MORNING AND HIGH PRESSURE WILL BUILD IN WITH A
LESS HUMID AIRMASS AND COOLER TEMPS. BELOW NORMAL TEMPS ARE
EXPECTED WITH HIGHS ON THURSDAY IN THE 80S AND LOWS THURSDAY NIGHT
IN THE 60S. TEMPS WILL CLIMB FRIDAY AND SATURDAY AS UPPER RIDGING
BUILDS IN. HIGHS WILL APPROACH 90 ON FRIDAY AND LOWER 90S ON
SATURDAY. CUT MEX TEMPS A FEW DEGREES SINCE IT HAS BEEN TOO WARM
ALL SUMMER.
SATURDAY NIGHT THROUGH SUNDAY NIGHT...UPPER RIDGE STARTS TO
WEAKEN SATURDAY NIGHT AND WEAK NORTHWEST FLOW DEVELOPS WITH A
BOUNDARY LOCATED TO THE NORTH OF THE AREA. THIS COULD BE AN MCS
SCENARIO. BY SUNDAY AND SUNDAY NIGHT THE EASTERN U.S. TROF
STRENGTHENS ONCE AGAIN AS MORE ENERGY DIPS SOUTH FROM CANADA. THIS
DRIVES A COLD FRONT SOUTH THROUGH THE AREA SUNDAY AND SUNDAY
NIGHT. EXPECT CHANCES FOR SHOWERS AND THUNDERSTORMS FOLLOWED BY
COOLER AND DRIER WEATHER BY EARLY NEXT WEEK. TEMPS LOOKS TO BE
WELL BELOW NORMAL MONDAY INTO MUCH OF NEXT WEEK.
SJM
&&
.AVIATION...
00Z TAF CYCLE
MAINLY VFR CONDITIONS WILL CONTINUE FOR MUCH OF THE FORECAST
PERIOD. SOME AREAS OF FOG ARE EXPECTED TO DEVELOP OVERNIGHT WHICH
MAY REDUCE VISIBILITIES TO MVFR OR EVEN IFR LEVELS. WINDS WILL BE
LIGHT AND MAINLY FROM THE SOUTHWEST FOR MUCH OF THE FORECAST
PERIOD.
ARS
&&
.MEG WATCHES/WARNINGS/ADVISORIES...
AR...NONE.
MO...NONE.
MS...NONE.
TN...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS SAN ANGELO TX
615 PM CDT Tue Jul 22 2014
.AVIATION...
/00Z TAFS/
A few very high based, very isolated, showers and thunderstorms
developing across West Central Texas. Radar trends suggest that the
Junction and Sonora sites, KJCT and KSOA, would be the only 2 that
might be affected by one of the storms, and even that would be highly
unlikely. Thus, will not mention in the terminal forecast at this
time. Will monitor and update as needed. Otherwise, VFR conditions
and east to southeast winds should continue.
&&
.PREV DISCUSSION... /ISSUED 330 PM CDT TUE JUL 22 2014/
SHORT TERM...
(Tonight and Wednesday)
A strong subtropical ridge remains anchored over the southern
Rockies this afternoon with 500 mb heights approaching 600 dam at
the center of the anticyclone. Isolated thunderstorms have developed
over portions of West TX, basically between Lubbock and San Angelo,
moving southwest toward the Permian Basin. A few cells have
developed within the CWA from near Sweetwater to Sterling City.
Surface temperatures approaching 100 degrees have effectively
removed the cap, tapping into sufficient instability to support
thunderstorms. SPC mesoanalysis from the RAP indicates MLCAPE values
on the order of 1500 J/kg. With weak winds aloft, ordinary cells
will be the convective mode with a classic microburst profile in
place per point soundings. Isolated thunderstorms were carried
through 10 PM generally west of a line from Sweetwater to Mertzon.
Otherwise, we`ll see light winds overnight with temperatures falling
into the low to mid 70s by sunrise. Any thunderstorms lingering into
the evening hours should quickly dissipate by sunset. Temperatures
will again warm to near 100 degrees Wednesday afternoon with light
winds from a generally easterly direction.
Johnson
LONG TERM...
(Wednesday Night through Tuesday)
An upper ridge centered over northern New Mexico and the northern
Panhandle and extending north into south-central Canada will
continue to minimize our precipitation chances while giving us above
normal temperatures through the coming weekend. A developing upper
trough over the eastern half of then nation will displace the upper
ridge to the west through the by the beginning of next week. As the
upper ridge moves west there will be some relief from the unseasonal
heat as afternoon highs drop from the upper 90s and triple digits
down to the mid and upper 90s beginning next Monday. Models are
indicating a frontal boundary moving as far south as the Red River
Valley on Monday may provide a focus for some convective activity.
At this time the best chances of rainfall would be north of the
forecast area with a slight chance of some activity moving south
into at least our northern CWA. The models are also showing a TUTT
low mowing west over deep south Texas which should keep any
associated rainfall south of our area. In any event, given the
inherent uncertainty in the models this far out, will keep the
forecast dry at this time.
15
&&
.PRELIMINARY POINT TEMPS/POPS...
Abilene 74 99 74 100 74 / 0 5 5 5 5
San Angelo 73 100 71 101 72 / 5 5 5 10 5
Junction 71 98 71 98 72 / 0 5 5 10 10
&&
.SJT WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
07
AREA FORECAST DISCUSSION
NWS MILWAUKEE/SULLIVAN WI
858 PM CDT TUE JUL 22 2014
.UPDATE...
THE FRONT WILL EXIT THE SOUTHEAST CORNER OF KENOSHA COUNTY WITHIN
A FEW HOURS...BY 03Z WED. STORMS JUST COULDN/T GET GOING ALONG THE
FRONT GIVEN A WEAK ELEVATED CAP THAT LINGERED INTO THE LATE
AFTERNOON AND THEN ONCE IT DISAPPEARED...THE FORCING WAS JUST SO
WEAK THAT STORMS COULD NOT BE TRIGGERED NOR SUSTAINED. THERE WAS
ALSO A WIND SHIFT AHEAD OF THE FRONT THAT BROUGHT PREFRONTAL
WESTERLY WINDS...A SURE SIGN OF WEAK LOW LEVEL FORCING.
ANYWAY...LOOK FOR COOLER CONDITIONS BEHIND THE FRONT OVERNIGHT
WITH TEMPS BY MORNING DROPPING INTO THE LOWER TO MID 60S WITH MUCH
LOWER DEW POINTS HEADING IN.
&&
.AVIATION/06Z TAFS/...
VFR CONDITIONS EXPECTED THROUGH THE TAF PERIOD AS HIGH PRESSURE
BUILDS IN BEHIND A DEPARTING COLD FRONT. WINDS WILL SHIFT TO THE
NORTHEAST OVERNIGHT AND BE A BIT BRISK DURING THE DAY ON
WEDNESDAY...ESPECIALLY OVER THE SOUTHEAST TAF SITES OF
KMKE/KENW/KUES.
&&
.MARINE...
NORTHEAST WINDS DEVELOPING IN THE WAKE OF THE COLD FRONT...WITH
HIGH PRESSURE BUILDING IN...WILL BRING LARGE WAVES BY WEDNESDAY
MORNING. WILL HOIST ANOTHER SMALL CRAFT ADVISORY RUNNING FROM 06Z
WED...TONIGHT...THROUGH WEDNESDAY EVENING.
&&
.PREV DISCUSSION... /ISSUED 355 PM CDT TUE JUL 22 2014/
TONIGHT...FORECAST CONFIDENCE - MEDIUM.
HEAT INDEX VALUES ENDED UP EXCEEDING 100 FROM MADISON AND WEST LATE
THIS AFTERNOON AFTER THE LOW CLOUDS CLEARED AWAY. MADISON REACHED A
HIGH OF 90 OR GREATER FOR THE FIRST TIME THIS YEAR.
SPC TRIMMED THE SLIGHT RISK A LITTLE FURTHER SOUTHEAST AGAIN WITH
THE 3 PM UPDATE. MESOSCALE MODELS CONTINUE TO KEEP THE AREA CAPPED
/NO CONVECTION/ UNTIL THE FRONT GETS INTO FAR SOUTHEAST WI OR EVEN
NORTHEAST IL LATE THIS AFTERNOON BETWEEN 22Z AND 00Z. SPC
MESOANALYSIS RAP IS SHOWING ERODING CIN ALONG THE FRONT IN CENTRAL
WI...SO I WILL CONTINUE THE SLIGHT CHANCE ALONG THE FRONT AS IT
MOVES SOUTHEAST THROUGH THE MKX FORECAST AREA. WE CANNOT RULE STORM
DEVELOPMENT GIVEN THE HIGH DEWPOINTS...SURFACE FRONT...VERY HIGH
CAPE OVER 4000 J/KG AND SIGNS OF SLIGHT UPSTREAM COOLING AT 700-
850MB.
THE INHIBITING FACTORS FOR CONVECTION ARE: THE CAP. THE WESTERLY
WINDS JUST AHEAD OF THE SURFACE AND 850MB FRONTS ARE LIMITING THE
LOW LEVEL CONVERGENCE. WE WILL HAVE TO SIT AND WAIT TO SEE IF THE
CAP BREAKS AS THE SURFACE FRONT REACHES SOUTHEAST WI. THERE IS
LIMITED BULK SHEAR OF 25 TO 30 KNOTS. ISOLATED SEVERE HAIL AND WINDS
WILL BE POSSIBLE. PRECIPITABLE WATER VALUES AROUND 2 WILL LEAD TO
VERY HEAVY RAIN WITH ANY THUNDERSTORMS. URBAN FLOODING WILL BE
POSSIBLE.
PRECIP CHANCES EXIT WITH FRONT LATE THIS EVENING WITH COOLER AND
DRIER AIR MOVING IN. TEMPERATURES DOWN INTO THE LOWER 60S AND DEW
POINTS IN THE MID TO UPPER 50S BY WEDNESDAY MORNING.
WEDNESDAY...FORECAST CONFIDENCE HIGH.
HIGH PRESSURE...DRIER AND AND COOLER TEMPERATURES WILL SETTLE INTO
THE REGION. LOOK FOR DIURNAL CUMULUS CLOUDS TO DEVELOP BY LATE
MORNING AND LINGER THROUGH EARLY AFTERNOON DUE TO STEEP LOW LEVEL
LAPSE RATES. STEADY NORTH WINDS WILL GRADUALLY DIMINISH DURING THE
AFTERNOON. WINDS WILL BE HIGHEST NEAR THE LAKE.
WEDNESDAY NIGHT THROUGH THURSDAY...FORECAST CONFIDENCE - HIGH.
THE QUIET AND LESS HUMID WEATHER WILL CONTINUE THROUGH THURSDAY AS A
HIGH PRESSURE RIDGE AND DRIER DEWPOINTS HOLD SWAY ACROSS THE WESTERN
GTLAKES. EXPECT PATCHY FOG LATER WED NIGHT DUE TO LIGHT BOUNDARY
LAYER WINDS AND LINGERING DEWPOINTS IN THE LOW TO MID 50S. EXPECT
SOME LOCATIONS TO DIP DOWN INTO THE 40S LATE WED NIGHT.
THURSDAY NIGHT AND FRIDAY...FORECAST CONFIDENCE - LOW.
CONSIDERABLE DIFFERENCES BETWEEN SHORT TERM GUIDANCE IN HANDLING OF
LOW TO MID LEVEL FORCING DURING THIS PERIOD. GFS ONLY GUIDANCE IN
BRINGING CONVECTION ASSOCIATED WITH WARM FRONT SOUTHEAST ACROSS
SOUTHERN WI ON FRIDAY. MEANWHILE...CANADIAN MAINTAINS WMFNT
ORIENTATION FARTHER SOUTH ACROSS MO/SRN IL. LATEST ECMWF A BLEND
BETWEEN THE TWO WHICH CLIPS PORTIONS OF SW INTO SOUTH CENTRAL WI
WITH CONVECTION GENERATED BY MOISTURE AND WARM AIR ADVECTION RETURN.
WL LEAN TOWARD MORE SOUTHERN SOLUTION AND KEEP LOWER POPS IN THE
WEST AND SOUTH DURING THIS PERIOD AS LEANING TOWARD DRIER SOLUTION
WITH BETTER CHANCE FOR CONVECTION FARTHER WEST AND SOUTH. ECMWF AND
NAM SHOW STRONGER W-NW FLOW STEERING FLOW ACROSS SRN WI WHILE GFS
STRONGER SW. GFS REMAINS OUTLIER AT THIS POINT. TOO MANY
DESCREPANCIES SO CONFIDENCE REMAINS LOW.
FRIDAY NIGHT THROUGH TUESDAY - FORECAST CONFIDENCE - LOW
TRENDING TOWARD MEDIUM.
LIKE NCEP WPC BLENDED...PREFER ENSEMBLE OF MEDIUM RANGE GUIDANCE FOR
THIS FORECAST PERIOD. MOST OF THE MEDIUM RANGE GUIDANCE IS SHOWING
SOMEWHAT BETTER AGREEMENT THAN 24 HOURS AGO...AND ARE CONVERGING ON
A SOMEWHAT SIMILAR SOLUTION.
WEAKENING MID-LEVEL RIDGE OVER NORTHERN PLAINS CONTINUES TO WEAKEN
AND FLATTEN EARLY THIS FORECAST PERIOD AS LOW PRESSURE MOVES ACROSS
SOUTHERN CANADA. GFS CONTINUES TO PHASE THIS SYSTEM WITH EASTERN
CANADA LONG WAVE TROUGH A BIT QUICKER THAN CANADIAN/ECMWF SOLUTIONS.
GFS BRINGS SHORT WAVE ACROSS WI SAT NIGHT INTO SUN...WHILE OTHER
SOLUTIONS ARE SLOWER...LATER SUNDAY INTO SUNDAY NIGHT. HENCE WL
NEED TO KEEP CHANCE POPS GOING OVER THE WEEKEND AS UPPER LEVEL
TROUGH MOVES THROUGH REGION.
BY MONDAY...NORTHWEST WINDS IN THE LOW TO MID LEVELS WILL HAVE
USHERED COOLER AND DRIER AIR INTO SRN WI...HOWEVER WEAK RIPPLES IN
FAST NORTHERLY FLOW MAY GENERATE -SHRA.
AVIATION/00Z TAFS/...
A COLD FRONT MOVING SOUTHEAST THROUGH SOUTHERN WI WILL BRING A
CHANCE OF SHOWERS AND THUNDERSTORMS ALONG IT LATE THIS AFTERNOON.
THE CHANCE WILL INCREASE AS THE FRONT GETS INTO FAR SOUTHEAST
WISCONSIN AROUND 6 PM...ESPECIALLY KENOSHA AND THEN SOUTHWARD INTO
NORTHEAST IL.
ANY THUNDERSTORMS WILL BRING MVFR CIGS/VSBYS IF THEY DEVELOP. EXPECT
VERY HEAVY RAIN. WINDS WILL BECOME NORTHWEST BEHIND THE FRONT...
THEN NORTH TO NORTHEAST OVERNIGHT. EXPECT A PERIOD OF BROKEN VFR
CUMULUS CLOUDS WED MIDDAY ON STEADY NORTHERLY WINDS.
MARINE...SMALL CRAFT ADVISORY IN EFFECT UNTIL 9 PM. WINDS AND WAVES
WILL RISE ON WEDNESDAY IN THE WAKE OF THE COLD FRONT. A SMALL CRAFT
ADVISORY WILL LIKELY BE NEEDED.
BEACHES...MILWAUKEE...RACINE AND KENOSHA COUNTIES WILL BE IN A HIGH
RISK OF SWIMMING HAZARDS LATER TONIGHT AND WEDNESDAY. SHEBOYGAN AND
OZAUKEE COUNTY BEACHES WILL BE IN A MODERATE RISK OF SWIMMING
HAZARDS TONIGHT AND HIGH RISK WEDNESDAY.
&&
.MKX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
LM...SMALL CRAFT ADVISORY FROM 1 AM WEDNESDAY TO 1 AM CDT THURSDAY
FOR LMZ644>646.
SMALL CRAFT ADVISORY FROM 1 AM TO 7 PM CDT WEDNESDAY FOR LMZ643.
&&
$$
UPDATE...DAVIS
TONIGHT/WEDNESDAY AND AVIATION/MARINE...MRC
WEDNESDAY NIGHT THROUGH TUESDAY...MBK
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
332 PM CDT MON JUL 21 2014
.SHORT TERM...(THIS EVENING THROUGH TUESDAY)
ISSUED AT 331 PM CDT MON JUL 21 2014
MAIN FORECAST CONCERNS ARE SEVERE THUNDERSTORM POTENTIAL LATE
TONIGHT OVER NORTH CENTRAL WISCONSIN AND HEAT INDEX VALUES LATE
TUESDAY MORNING INTO TUESDAY AFTERNOON OVER PORTIONS OF NORTHEAST
IOWA INTO FAR SOUTHWEST WISCONSIN.
LATEST RADAR IMAGERY SHOWS THUNDERSTORMS DEVELOPING OVER PORTIONS OF
CENTRAL NORTH DAKOTA. THESE SHOULD BE THE BIRTH OF A THUNDERSTORM
COMPLEX THAT WILL RACE EAST TONIGHT ACROSS NORTHERN MINNESOTA INTO
PORTIONS OF NORTHERN WISCONSIN AND UPPER MICHIGAN. MOST OF THE
MESOSCALE MODEL GUIDANCE KEEPS THIS COMPLEX NORTH OF THE INTERSTATE
94 CORRIDOR. HOWEVER...THE NAM...WHICH IS A MAJOR OUTLIER AT THIS
TIME...SHOWS CONVECTION FIRING OVER WEST CENTRAL MINNESOTA LATE
THIS AFTERNOON INTO THIS EVENING THEN THIS CONVECTION RACES
SOUTHEAST INTO THE FORECAST AREA. LOOKING AT FORECAST SOUNDINGS
OVER MUCH OF THE FORECAST AREA THERE IS AN IMPRESSIVE ELEVATED
MIXED LAYER WHICH IS RESULTING IN A STRONG CAP IN PLACE. THE
CONVECTION WILL HAVE TO OVERCOME THIS CAP AND WITHOUT A STRONG LOW
LEVEL JET THIS WILL BE DIFFICULT TO DO. THE 17Z HRRR SHOWS A FEW
CELLS MAKING IN INTO WEST CENTRAL WISCONSIN AFTER MIDNIGHT SO WILL
HAVE TO SEE IF THIS PANS OUT. HAVE DECIDED TO REDUCE POPS ACROSS
MUCH OF THE FORECAST AREA TONIGHT WITH THE EXCEPTION OF CLARK AND
TAYLOR COUNTY WHERE THE MCS COULD IMPACT THESE AREAS WITH DAMAGING
WINDS THE MAY CONCERN.
A COLD FRONT THEN SAGS SOUTH ACROSS THE AREA ON TUESDAY. SOME OF
THE WARMEST AIR AT 925 MB MAKES IT INTO NORTHEAST IOWA INTO FAR
SOUTHWEST WISCONSIN WHERE 925 MB TEMPERATURES CLIMB TO AROUND 27
C. TEMPERATURES COULD CLIMB TO THE UPPER 80S TO AROUND 90 OVER
PORTIONS OF NORTHEAST IOWA AND FAR SOUTHWEST WISCONSIN. THESE
TEMPERATURES COMBINED WITH DEWPOINTS IN THE MID TO UPPER 70S WILL
PRODUCE HEAT INDEX VALUES AROUND 100. THIS HEAT LOOKS TO BE VERY
SHORT LIVED WITH THE COLD FRONT SWEEPING THROUGH LATE TOMORROW
AFTERNOON SO HAVE HAVE NOT ISSUED A HEAT ADVISORY AT THIS TIME.
SHOWERS AND STORMS WILL BE POSSIBLE ALONG THE FRONT TUESDAY
AFTERNOON INTO EARLY TUESDAY EVENING BUT AGAIN THE CAP WILL BE A
MAJOR LIMITING FACTOR. MOST OF THE FORECAST MODELS KEEP THE AREA
DRY. GIVEN THE AMOUNT OF SURFACE BASED CAPE THAT DEVELOPS AHEAD
OF THE FRONT OVER NORTHEAST IOWA AND FAR SOUTHWEST
WISCONSIN...COULD SEE A STORM OR TWO DEVELOP ALONG THE FRONT LATE
IN THE AFTERNOON SO WILL KEEP CHANCES FOR SHOWERS AND
THUNDERSTORMS THROUGH THE LATE AFTERNOON INTO THE EARLY EVENING.
VERY COMFORTABLE TEMPERATURES RETURN IN THE WAKE OF THE FRONT
TUESDAY NIGHT WITH TEMPERATURES FALLING INTO THE UPPER 50S TO
LOWER 60S.
.LONG TERM...(TUESDAY NIGHT THROUGH MONDAY)
ISSUED AT 331 PM CDT MON JUL 21 2014
HIGH PRESSURE BUILDS INTO THE REGION TUESDAY NIGHT AND REMAINS OVER
THE REGION THROUGH THURSDAY PROVIDING QUIET AND COMFORTABLE CONDITIONS.
PLAN ON HIGHS IN THE 70S WITH LOWS IN THE 50S TO AROUND 60. WITH
THE HIGH OVERHEAD WILL HAVE TO KEEP AN EYE ON THE POTENTIAL FOR
SOME PATCHY VALLEY FOG DURING THE LATE NIGHT AND EARLY MORNING
HOURS THURSDAY MORNING...BUT CLOUD COVER COULD PREVENT THIS FROM
FORMING. CHANCES FOR SHOWERS AND THUNDERSTORMS RETURN THURSDAY
NIGHT INTO THE WEEKEND AS ACTIVE NORTHWEST FLOW SETS UP ACROSS THE
REGION. A TROUGH DIVES INTO THE UPPER MISSISSIPPI RIVER VALLEY ON
SUNDAY AND DEEPENS A LARGER SCALE TROUGH OVER THE ENTIRE GREAT
LAKES REGION EARLY NEXT WEEK. THIS WOULD SET THE STAGE FOR WELL
BELOW NORMAL TEMPERATURES OVER THE AREA GOING INTO EARLY NEXT
WEEK.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON)
ISSUED AT 1225 PM CDT MON JUL 21 2014
GOOD VFR CONDITIONS WILL PREVAIL THIS AFTERNOON AND EVENING AS
DIURNAL WARMING INCREASES THE MIXING DEPTH...WITH ANY CUMULUS IN THE
4K-5K FT RANGE. INCREASED MIXING SHOULD KEEP THE BOUNDARY LAYER HAZE
TO A MINIMUM AS WELL. THE DEEPER MIXING AND MDT PRESSURE GRADIENT
ACROSS THE AREA WILL RESULT IN SOME WIND GUSTS IN THE 20KT RANGE AT
BOTH KRST/KLSE THIS AFTERNOON.
A STORM COMPLEX IS STILL EXPECTED TO DEVELOP OVER EASTERN ND/
NORTHERN MN THIS EVENING. BULK OF THE FORCING TAKES THIS COMPLEX
EAST-SOUTHEAST ACROSS MN/NORTHERN WI OVERNIGHT/EARLY TUE MORNING. A
COUPLE OF MODEL SOLUTIONS BRING THIS COMPLEX SOUTHEAST DOWN THE MS
RIVER OVERNIGHT...AND INTO THE KLSE/KRST AREAS IN THE 09Z-12Z TIME
FRAME. THIS LOOKS RATHER UNLIKELY WITH VERY WARM TEMPERATURES AROUND
700MB CAPPING THE AIRMASS OVER SOUTHEAST MN/SOUTHWEST WI TONIGHT AND
THE MAIN FORCING OVER NORTHERN WISCONSIN. LEFT THE KRST TAF DRY LATE
TONIGHT AND ONLY CARRIED A 10-13Z VCSH MENTION AT KLSE. GRADIENT
WINDS OF 10-15KTS TONIGHT SHOULD KEEP LATE NIGHT BR TO A MINIMUM. A
COLD FRONT DROPS ACROSS THE AREA TUE...AROUND 15Z AT KRST AND 18Z AT
KLSE. FRONT WILL BRING A SWITCH TO NORTHWEST WINDS AND A DRIER LOW
LEVEL AIRMASS TO THE TAF SITES LATER TUE MORNING/TUE AFTERNOON.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...HEAT ADVISORY UNTIL 9 PM CDT THIS EVENING FOR MNZ079-086-087-094-
095.
IA...HEAT ADVISORY UNTIL 9 PM CDT THIS EVENING FOR IAZ008-009-018-019.
&&
$$
SHORT TERM...WETENKAMP
LONG TERM...WETENKAMP
AVIATION.....RRS
AREA FORECAST DISCUSSION
NWS CHEYENNE WY
841 PM MDT TUE JUL 22 2014
.UPDATE...
ISSUED AT 835 PM MDT TUE JUL 22 2014
REGIONAL RADARS SHOWED ISOLATED STRONG CONVECTION THAT PRODUCED
LARGE HAIL NORTHWEST OF CHEYENNE EARLIER THIS EVENING HAS DISSIPATED
AS IT MOVED INTO THE SOUTHERN NEBRASKA PANHANDLE. A CLUSTER OF
STRONG TO SEVERE TSTORMS WAS MOVING SOUTHEAST ALONG A INSTABILITY
AXIS /SBCAPES 2000-3000 J/KG/ TOWARD THE NORTHERN NEBRASKA PANHANDLE.
THESE STORMS SHOULD EXIT OUR NORTHERN PANHANDLE ZONES BY MIDNIGHT.
ANOTHER ACTIVE TSTORM CLUSTER OVER SOUTHEAST MT SHOULD PASS NORTH OF
OUR NORTHERN CWA TONIGHT. UPDATED ZONES TO INCREASE POPS OVER THE
NORTHERN PANHANDLE AND REMOVE THEM OVER SOUTHEAST WY AND SOUTHERN
NEBRASKA PANHANDLE.
&&
.SHORT TERM...(THIS EVENING THROUGH THURSDAY NIGHT)
ISSUED AT 306 PM MDT TUE JUL 22 2014
FAR LESS COVERAGE OF CU COMPARED TO THE SAME TIME MONDAY WHICH
SURELY IS INDICATIVE OF THE WARMER TEMPS ALOFT. SFC MOISTURE HAS
INCREASED BEHIND LAST NIGHTS WEAK BOUNDARY...WITH THE 50F
ISODROSOTHERM BANKED UP TO THE FRONT RANGE. AM BEGINNING TO SEE SOME
WEAK CONVECTIVE DEVELOPMENT MAINLY IN THE VICINITY OF THE NRN
LARAMIE RANGE...AND SOME NR THE SNOWY AND SOUTHERN LARAMIE RANGE
TOO. MESOANALYSIS SHOWS A PRETTY HEALTHY CAPPING INVERSION REMAINS
IN PLACE...ESPECIALLY OVR THE ERN PLAINS. EXPECT THIS CAP CONTINUE
TO ERODE THRU THE AFTERNOON. THE STRONGER CAP WILL MEAN DEEP
CONVECTION WILL BE A BIT LATER IN DEVELOPING...WHICH ACCORDING TO
THE HRRR WILL BE BETWEEN 3-6 PM. LARAMIE COUNTY AND THE SOUTHERN END
OF GOSHEN/PLATTE COUNTIES LOOK TO SEE THE BEST CHANCE INITIALLY.
WILL SEE ADDITIONAL DEVELOPMENT OVR NORTHEAST WYOMING DIVE SOUTHEAST INTO
FAR EAST CENTRAL WYOMING AND THE NRN NEBRASKA PANHANDLE THIS
EVENING. IT IS THIS AREA WHERE SEVERE POTENTIAL WILL BE GREATEST
WITH SBCAPES OF AROUND 2000 J/KG ONCE THE CAP BREAKS. THIS
CONVECTION WILL DISSIPATE BY AROUND SUNSET.
ATTENTION THEN TURNS TO A BETTER CHANCE FOR SEVERE THUNDERSTORM
DEVELOPMENT WEDNESDAY AFTERNOON. THERMODYNAMIC PROFILES WILL BE MORE
CONDUCIVE FOR THUNDERSTORM DEVELOPMENT WEDNESDAY AS MID-LEVEL
HEIGHTS/TEMPS FALL WITH THE APPROACH OF SHORTWAVE ENERGY. THIS WILL
MEAN LESS OF A CAP AND A LIKELY EARLIER START TO CONVECTIVE
INITIATION...WHICH SHOULD OCCUR OVR THE SNOWY/SIERRA MADRE RANGES BY
MIDDAY. PROGGED SBCAPES OVR THE ERN PLAINS CLIMB ABOVE 3000 J/KG
WEDNESDAY AFTERNOON AND WHEN COMBINED WITH DEEP LAYER SHEAR OF 25-30
KNOTS SHOULD BE SUFFICIENT FOR SOME CONVECTIVE ACTIVITY BECOMING
SEVERE. STORMS WILL SPREAD ONTO THE SOUTHEAST WYOMING PLAINS
WEDNESDAY AFTERNOON AND INTO THE WESTERN NEBRASKA PANHANDLE DURING
THE EVENING. AREAS OVR THE SOUTHERN PANHANDLE MAY BE INFLUENCED A
BIT TOO MUCH BY THE CAP...WHICH MAY LIMIT CONVECTIVE STRENGTH THERE.
CONVECTION AGAIN WILL WANE WITH LOSS OF INSOLATION.
FIRST SHORTWAVE PUSHES THRU THURSDAY MORNING WITH A TRAILING
SHORTWAVE POISED TO MOVE THRU THURSDAY AFTERNOON. INSTABILITY AXIS
WILL BE FLATTENED AND WEAKENED BY THE INITIAL SHORTWAVE. SO EXPECT A
LESS FAVORABLE ENVIRONMENT FOR SEVERE THUNDERSTORM POTENTIAL. EVEN
SO...WEAK INSTABILITY PARAMETERS WILL BE SUFFICIENT FOR AT LEAST
SOME ISOLATED CONVECTIVE POTENTIAL. THURSDAY WILL BE THE WARMEST DAY
OF THE PERIOD WITH HIGH TEMPERATURES THAT WILL AGAIN REACH 90S AT
MOST LOCATION AND LOW TRIPLE DIGITS OVER LOWER ELEVATIONS OF THE
WESTERN NEBRASKA PANHANDLE.
.LONG TERM...(FRIDAY THROUGH MONDAY)
ISSUED AT 306 PM MDT TUE JUL 22 2014
HIGH PRESSURE CONTINUES TO REMAIN DOMINANT OVER THE FOUR CORNERS
REGION BUT BEGINS TO ERODE TO THE SOUTH OVER THE WEEKEND. FAIRLY POTENT
TROUGH OF LOW PRESSURE MOVES ACROSS THE SOUTHERN CANADIAN PROVINCES
AND BRINGS A SERIES OF ASSOCIATED COOL FRONTS ACROSS THE AREA (THE
STRONGEST FRONT WILL BE SAT EVENING). UPSLOPE FLOW LOOKS TO DEVELOP
BY FRI AFTN AS DEW POINTS APPROACH THE MID 50S OVER THE PANHANDLE.
COULD SEE SOME ISOLATED SHOWERS AND THUNDERSTORMS DURING THIS
TIME FRAME BOTH FRI AND SAT SO HAVE KEPT SOME SLIGHT POPS IN THE
FCST. THE ECMWF IS MORE MOIST THAN THE GFS ATTM AND GENERATES A
BETTER COVERAGE OF STORMS EACH AFTN AND EVENING. TEMPS BEGIN TO COOL
TO MORE SEASONABLE LEVELS IN THE LOW TO MID 80S FOR SUNDAY...BUT THE
RIDGE BEGINS TO BUILD BACK INTO THE AREA AND TEMPS SHOULD WARM TO
THE MID 80S BY MONDAY FOR SOUTHEASTERN WY AND NEAR 90 FOR AREAS OF
THE PANHANDLE AS 700 MB TEMPS WARM TO NEAR 15C.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z WEDNESDAY AFTERNOON)
ISSUED AT 641 PM MDT TUE JUL 22 2014
VFR CONDITIONS WILL BE A GENERAL RULE. HOWEVER...ISOLATED SHOWERS
AND THUNDERSTORMS ARE POSSIBLE THROUGH 06Z WED. GUSTY AND ERRATIC
WINDS AND HAIL ALOFT ARE THE MAIN AVIATION HAZARDS. IT IS POSSIBLE
THAT THESE STORMS COULD BECOME SEVERE WITH LARGE HAIL AS WELL AS
DAMAGING WINDS. BRIEF MVFR CONDITIONS ARE POSSIBLE BENEATH ANY
THUNDERSTORMS AS WELL. INCREASING CLOUDS IN THE MID LEVELS ON
WEDNESDAY AFTERNOON WITH ANOTHER GOOD POSSIBILITY OF SHOWERS AND
THUNDERSTORMS AFFECTING THE HIGH PLAINS.
&&
.FIRE WEATHER...
ISSUED AT 306 PM MDT TUE JUL 22 2014
WINDS HAVE HELD BELOW CRITICAL THRESHOLDS THUS FAR TODAY...DESPITE
RELATIVE HUMIDITIES THAT HAVE DROPPED BELOW 15 PERCENT. SOME
ISOLATED SHOWERS AND THUNDERSTORMS ARE EXPECTED TO DEVELOP OVER
LARAMIE COUNTY LATE THIS AFTERNOON AND OVER EXTREME EAST CENTRAL
WYOMING AND THE NORTHERN NEBRASKA PANHANDLE THIS EVENING. WEDNESDAY
WILL PROVIDE A BETTER OPPORTUNITY FOR AFTERNOON AND EVENING
THUNDERSTORMS ACROSS THE DISTRICT...SOME OF WHICH COULD POTENTIALLY
BECOME SEVERE IN LOCATIONS EAST OF THE LARAMIE RANGE. DRIER AND
BREEZIER CONDITIONS WILL EXIST OVER WESTERN CARBON AND CONVERSE
COUNTIES ON WEDNESDAY. CONDITIONS WILL LIKELY BECOME NEAR CRITICAL
IN THESE AREAS WEDNESDAY. THURSDAY LOOKS POTENTIALLY MORE CRITICAL
OVER WESTERN CARBON AND CONVERSE COUNTIES AND WILL LIKELY NEED TO
ISSUE A HEADLINE IN TIME. AFTERNOON AND EVENING SHOWER AND
THUNDERSTORM CHANCES WILL CONTINUE THURSDAY AND FRIDAY MAINLY FOR
AREAS EAST OF THE LARAMIE RANGE.
&&
.CYS WATCHES/WARNINGS/ADVISORIES...
WY...NONE.
NE...NONE.
&&
$$
UPDATE...JAMSKI
SHORT TERM...HAHN
LONG TERM...FINCH
AVIATION...HAMMER
FIRE WEATHER...HAHN
AREA FORECAST DISCUSSION
NWS CHEYENNE WY
646 PM MDT TUE JUL 22 2014
.SHORT TERM...(THIS EVENING THROUGH THURSDAY NIGHT)
ISSUED AT 306 PM MDT TUE JUL 22 2014
FAR LESS COVERAGE OF CU COMPARED TO THE SAME TIME MONDAY WHICH
SURELY IS INDICATIVE OF THE WARMER TEMPS ALOFT. SFC MOISTURE HAS
INCREASED BEHIND LAST NIGHTS WEAK BOUNDARY...WITH THE 50F
ISODROSOTHERM BANKED UP TO THE FRONT RANGE. AM BEGINNING TO SEE SOME
WEAK CONVECTIVE DEVELOPMENT MAINLY IN THE VICINITY OF THE NRN
LARAMIE RANGE...AND SOME NR THE SNOWY AND SOUTHERN LARAMIE RANGE
TOO. MESOANALYSIS SHOWS A PRETTY HEALTHY CAPPING INVERSION REMAINS
IN PLACE...ESPECIALLY OVR THE ERN PLAINS. EXPECT THIS CAP CONTINUE
TO ERODE THRU THE AFTERNOON. THE STRONGER CAP WILL MEAN DEEP
CONVECTION WILL BE A BIT LATER IN DEVELOPING...WHICH ACCORDING TO
THE HRRR WILL BE BETWEEN 3-6 PM. LARAMIE COUNTY AND THE SOUTHERN END
OF GOSHEN/PLATTE COUNTIES LOOK TO SEE THE BEST CHANCE INITIALLY.
WILL SEE ADDL DEVELOPMENT OVR NORTHEAST WYOMING DIVE SOUTHEAST INTO
FAR EAST CENTRAL WYOMING AND THE NRN NEBRASKA PANHANDLE THIS
EVENING. IT IS THIS AREA WHERE SEVERE POTENTIAL WILL BE GREATEST
WITH SBCAPES OF AROUND 2000 J/KG ONCE THE CAP BREAKS. THIS
CONVECTION WILL DISSIPATE BY AROUND SUNSET.
ATTENTION THEN TURNS TO A BETTER CHANCE FOR SEVERE THUNDERSTORM
DEVELOPMENT WEDNESDAY AFTERNOON. THERMODYNAMIC PROFILES WILL BE MORE
CONDUCIVE FOR THUNDERSTORM DEVELOPMENT WEDNESDAY AS MID-LEVEL
HEIGHTS/TEMPS FALL WITH THE APPROACH OF SHORTWAVE ENERGY. THIS WILL
MEAN LESS OF A CAP AND A LIKELY EARLIER START TO CONVECTIVE
INITIATION...WHICH SHOULD OCCUR OVR THE SNOWY/SIERRA MADRE RANGES BY
MIDDAY. PROGD SBCAPES OVR THE ERN PLAINS CLIMB ABOVE 3000 J/KG
WEDNESDAY AFTERNOON AND WHEN COMBINED WITH DEEP LAYER SHEAR OF 25-30
KNOTS SHOULD BE SUFFICIENT FOR SOME CONVECTIVE ACTIVITY BECOMING
SEVERE. STORMS WILL SPREAD ONTO THE SOUTHEAST WYOMING PLAINS
WEDNESDAY AFTERNOON AND INTO THE WESTERN NEBRASKA PANHANDLE DURING
THE EVENING. AREAS OVR THE SOUTHERN PANHANDLE MAY BE INFLUENCED A
BIT TOO MUCH BY THE CAP...WHICH MAY LIMIT CONVECTIVE STRENGTH THERE.
CONVECTION AGAIN WILL WANE WITH LOSS OF INSOLATION.
FIRST SHORTWAVE PUSHES THRU THURSDAY MORNING WITH A TRAILING
SHORTWAVE POISED TO MOVE THRU THURSDAY AFTERNOON. INSTABILITY AXIS
WILL BE FLATTENED AND WEAKENED BY THE INITIAL SHORTWAVE. SO EXPECT A
LESS FAVORABLE ENVIRONMENT FOR SEVERE THUNDERSTORM POTENTIAL. EVEN
SO...WEAK INSTABILITY PARAMETERS WILL BE SUFFICIENT FOR AT LEAST
SOME ISOLATED CONVECTIVE POTENTIAL. THURSDAY WILL BE THE WARMEST DAY
OF THE PERIOD WITH HIGH TEMPERATURES THAT WILL AGAIN REACH 90S AT
MOST LOCATION AND LOW TRIPLE DIGITS OVER LOWER ELEVATIONS OF THE
WESTERN NEBRASKA PANHANDLE.
.LONG TERM...(FRIDAY THROUGH MONDAY)
ISSUED AT 306 PM MDT TUE JUL 22 2014
HIGH PRESSURE CONTINUES TO REMAIN DOMINANT OVER THE FOUR CORNERS
REGION BUT BEGINS TO ERODE TO THE SOUTH OVER THE WKND. FAIRLY POTENT
TROUGH OF LOW PRESSURE MOVES ACROSS THE SOUTHERN CANADIAN PROVINCES
AND BRINGS A SERIES OF ASSOCIATED COOL FRONTS ACROSS THE AREA (THE
STRONGEST FRONT WILL BE SAT EVENING). UPSLOPE FLOW LOOKS TO DEVELOP
BY FRI AFTN AS DEW POINTS APPROACH THE MID 50S OVER THE PANHANDLE.
COULD SEE SOME ISOLATED SHOWERS AND THUNDERSTORMS DURING THIS
TIMEFRAME BOTH FRI AND SAT SO HAVE KEPT SOME SLIGHT POPS IN THE
FCST. THE ECMWF IS MORE MOIST THAN THE GFS ATTM AND GENERATES A
BETTER COVERAGE OF STORMS EACH AFTN AND EVENING. TEMPS BEGIN TO COOL
TO MORE SEASONABLE LEVELS IN THE LOW TO MID 80S FOR SUNDAY...BUT THE
RIDGE BEGINS TO BUILD BACK INTO THE AREA AND TEMPS SHOULD WARM TO
THE MID 80S BY MONDAY FOR SOUTHEASTERN WY AND NEAR 90 FOR AREAS OF
THE PANHANDLE AS 700 MB TEMPS WARM TO NEAR 15C.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z WEDNESDAY AFTERNOON)
ISSUED AT 641 PM MDT TUE JUL 22 2014
VFR CONDITIONS WILL BE A GENERAL RULE. HOWEVER...ISOLATED SHOWERS
AND THUNDERSTORMS ARE POSSIBLE THROUGH 06Z WED. GUSTY AND ERRATIC
WINDS AND HAIL ALOFT ARE THE MAIN AVIATION HAZARDS. IT IS POSSIBLE
THAT THESE STORMS COULD BECOME SEVERE WITH LARGE HAIL AS WELL AS
DAMAGING WINDS. BRIEF MVFR CONDITIONS ARE POSSIBLE BENEATH ANY
THUNDERSTORMS AS WELL. INCREASING CLOUDS IN THE MID LEVELS ON
WEDNESDAY AFTERNOON WITH ANOTHER GOOD POSSIBILITY OF SHOWERS AND
THUNDERSTORMS AFFECTING THE HIGH PLAINS.
&&
.FIRE WEATHER...
ISSUED AT 306 PM MDT TUE JUL 22 2014
WINDS HAVE HELD BELOW CRITICAL THRESHOLDS THUS FAR TODAY...DESPITE
RELATIVE HUMIDITIES THAT HAVE DROPPED BELOW 15 PERCENT. SOME
ISOLATED SHOWERS AND THUNDERSTORMS ARE EXPECTED TO DEVELOP OVER
LARAMIE COUNTY LATE THIS AFTERNOON AND OVER EXTREME EAST CENTRAL
WYOMING AND THE NORTHERN NEBRASKA PANHANDLE THIS EVENING. WEDNESDAY
WILL PROVIDE A BETTER OPPORTUNITY FOR AFTERNOON AND EVENING
THUNDERSTORMS ACROSS THE DISTRICT...SOME OF WHICH COULD POTENTIALLY
BECOME SEVERE IN LOCATIONS EAST OF THE LARAMIE RANGE. DRIER AND
BREEZIER CONDITIONS WILL EXIST OVER WESTERN CARBON AND CONVERSE
COUNTIES ON WEDNESDAY. CONDITIONS WILL LIKELY BECOME NEAR CRITICAL
IN THESE AREAS WEDNESDAY. THURSDAY LOOKS POTENTIALLY MORE CRITICAL
OVER WESTERN CARBON AND CONVERSE COUNTIES AND WILL LIKELY NEED TO
ISSUE A HEADLINE IN TIME. AFTERNOON AND EVENING SHOWER AND
THUNDERSTORM CHANCES WILL CONTINUE THURSDAY AND FRIDAY MAINLY FOR
AREAS EAST OF THE LARAMIE RANGE.
&&
.CYS WATCHES/WARNINGS/ADVISORIES...
WY...NONE.
NE...NONE.
&&
$$
SHORT TERM...HAHN
LONG TERM...FINCH
AVIATION...HAMMER
FIRE WEATHER...HAHN
AREA FORECAST DISCUSSION...UPDATED
NWS MIAMI FL
146 AM EDT WED JUL 23 2014
.AVIATION...
THE WINDS WILL BE LIGHT OVER SOUTH FLORIDA TAF SITES EARLY THIS
MORNING BEFORE BECOMING EASTERLY AT 5 TO 10 KNOTS AFTER 15Z TODAY.
THE ONLY EXCEPTION TO THIS IS AT KAPF TAF SITE WITH THE WIND FLOW
WILL BE WESTERLY AFTER 16Z DUE TO THE WEST COAST SEA BREEZE
PUSHING INLAND. DRIER AIR IS STARTING TO WORK INTO SOUTH FLORIDA
EARLY THIS MORNING...BUT THERE WILL BE ENOUGH MOISTURE AROUND TO
ALLOW FOR THUNDERSTORMS TO DEVELOP ALONG BOTH SEA BREEZE TODAY.
THEREFORE...THE VCTS WILL REMAIN IN PLACE FOR ALL OF THE SOUTH
FLORIDA TAF SITES AFTER 15Z TODAY.
AT THIS TIME...THE TIMING OF THE SHOWERS AND THUNDERSTORMS TO
AFFECT THE TAF SITES IS UNKNOWN. THEREFORE...THE CEILING AND VIS
WILL REMAIN IN VFR CONDITIONS FOR TODAY FOR ALL OF THE TAF SITES.
HOWEVER...WHEN THE THUNDERSTORMS DO DEVELOP AROUND THE TAF SITES
THEN A TEMPO GROUP WILL BE ADDED FOR THE CEILING AND VIS.
&&
.AVIATION...54/BNB
.PREV DISCUSSION... /ISSUED 937 PM EDT TUE JUL 22 2014/
UPDATE...
THE AFTERNOON SHOWER AND THUNDERSTORM ACTIVITY DIMINISHED EARLIER
WITH VERY QUIET CONDITIONS EXPECTED TO PERSIST INTO THE OVERNIGHT
HOURS. THE LATEST HRRR MODEL RUN REFLECTS THIS
TREND...HOWEVER...DOES INDICATE SOME ISLTD/SCT ACTIVITY DEVELOPING
OVER THE ADJACENT ATLANTIC WATERS BY DAYBREAK WEDNESDAY. OVERNIGHT
TEMPERATURES ARE PROJECTED TO DIP INTO THE MID TO UPPER 70S ACROSS
THE LOCAL AREA FOR THE LOWS. OUTSIDE OF A FEW MINOR
ADJUSTMENTS...THE PREVIOUS FORECAST PACKAGE REMAINS ON TRACK THIS
EVENING WITH NO MAJOR UPDATES ANTICIPATED.
&&
85/AG
PREV DISCUSSION... /ISSUED 738 PM EDT TUE JUL 22 2014/
AVIATION...
MAINLY VFR CONDITIONS TO PREVAIL OVER THE NEXT 24 HOURS AT ALL
SITES OUTSIDE OF ANY THUNDERSTORMS. WINDS SHOULD BE MAINLY LIGHT
AND VARIABLE THROUGH THE NIGHT BEFORE SOUTHEASTERLY FLOW RETURNS
TOMORROW AFTERNOON. PLACED VCTS IN AT ALL SITES AFTER 15Z-16Z
TOMORROW ALTHOUGH BELIEVE MOST OF THE CONVECTION WILL REMAIN
ACROSS THE INTERIOR AND GULF COAST AS A GULF BREEZE SHOULD
DEVELOP.
**
PREV DISCUSSION... /ISSUED 230 PM EDT TUE JUL 22 2014/
DISCUSSION...
THE WEATHER PATTERN HAS NOT CHANGED MUCH FROM YESTERDAY. A LOW
PRESSURE CENTER IS SITTING OVER THE MOBILE ALABAMA AREA, AND AN
AREA OF HIGH PRESSURE IS SITUATED TO THE EAST. THIS HAS CONTINUED
THE SOUTHERLY FLOW OVER SOUTH FLORIDA, WHICH HAS MAINTAINED
ABUNDANT MOISTURE AND ENOUGH INSTABILITY TO BRING SHOWERS AND
THUNDERSTORMS TO THE AREA. THE CONVECTIVE ACTIVITY SHOULD DWINDLE
THROUGH THE EVENING HOURS, WITH THE LOSS OF DAYTIME HEATING.
MODELS ARE IN PRETTY GOOD AGREEMENT WITH THE LOW WEAKENING AND THE
HIGH STRENGTHENING SOMEWHAT AND BUILDING SLOWLY WESTWARD. THIS
WILL KEEP A GENERALLY SOUTHERLY FLOW OVER SOUTH FLORIDA. WHILE
TOMORROW WILL SEE ANOTHER ROUND OF WIDESPREAD ACTIVITY, THURSDAY
AND FRIDAY LOOK TO BE MORE TOWARDS THE INTERIOR, WITH SLIGHTLY
LOWER PROBABILITY EACH DAY, AS THE LOW SLOWLY WEAKENS AND THE HIGH
GRADUALLY BUILDS.
LONG TERM...
BERMUDA RIDGE AND RELATIVELY DRY ATLANTIC AIR WILL REGULATE
WEATHER THROUGH THE WEEKEND...RESULTING IN A BIT BELOW NORMAL RAIN
CHANCES...HIGHEST OVER INTERIOR DURING THE AFTERNOONS. MAXIMA WILL
BE NEAR AVERAGE FOR LATE JULY...MAINLY LOWER 90S...WITH MINIMA A
FEW DEGREES ABOVE NORMAL...RANGING FROM MID 70S TO AROUND 80F
ALONG THE ATLANTIC COAST.
MARINE...
HIGH PRESSURE WILL SLOWLY BUILD OVER THE ATLANTIC WATERS. WITH
THE CENTER OF THE HIGH TO THE EAST OF THE AREA, SOUTHERLY FLOW
WILL CONTINUE THROUGH THE REST OF THE WEEK. WITH THE FLOW BEING
RELATIVELY LIGHT, SEAS ARE NOT EXPECTED TO BUILD OVER THE NEXT
FEW DAYS. HOWEVER, THUNDERSTORMS MAY PRODUCE LOCALLY ROUGH
CONDITIONS.
&&
.PRELIMINARY POINT TEMPS/POPS...
WEST PALM BEACH 78 91 79 91 / 20 30 30 30
FORT LAUDERDALE 82 91 82 91 / 20 20 20 30
MIAMI 80 91 80 91 / 20 30 20 30
NAPLES 76 92 77 92 / 20 40 20 30
&&
.MFL WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
AM...NONE.
GM...NONE.
&&
$$
SHORT TERM...30/KOB
LONG TERM....13/SI
AVIATION...54/BNB
AREA FORECAST DISCUSSION
NWS NORTHERN INDIANA
126 AM EDT WED JUL 23 2014
.SYNOPSIS...
ISSUED AT 727 PM EDT TUE JUL 22 2014
A COLD FRONT WILL MOVE ACROSS THE REGION OVERNIGHT INTO WEDNESDAY
MORNING. SCATTERED SHOWERS AND THUNDERSTORMS ARE POSSIBLE ALONG THE
FRONT AS IT PASSES THROUGH THE AREA. COOLER AND DRIER AIR WILL
FILTER IN BEHIND THE FRONT FOR WEDNESDAY THROUGH THE END OF THE
WEEK. LOWS TONIGHT WILL BE IN THE MID 60S TO AROUND 70 DEGREES WITH
HIGHS ON WEDNESDAY IN THE 70S.
&&
.SHORT TERM...(THIS EVENING THROUGH WEDNESDAY)
ISSUED AT 306 PM EDT TUE JUL 22 2014
REGIONAL RADARS SHOWING ONGOING CONVECTION CONTINUES TO MOVE ACROSS
FAR NORTHERN GREAT LAKES/SOUTHERN CANADA WITH SURFACE LOW WHILE
EARLIER MCS DISSIPATING OVER THE MID MISSISSIPPI VALLEY WITH NEW
CELLS STARTING TO FORM OVER IOWA THIS AFTERNOON. WATER VAPOR IMAGERY
AND LATEST RUC ANALYSIS SHOWS SHORT WAVE TROF MOVING ACROSS LAKE
SUPERIOR WITH UPPER JET WELL TO THE NORTH OVER THE HUDSON BAY. THIS
DETACHMENT OF UPPER FORCING WILL BE PROBLEMATIC FOR CONVECTION
MAINTAINING ALONG THE COLD FRONT AS IT MOVES THROUGH OVERNIGHT. BEST
CHANCES APPEAR TO BE IN THE NW CWA AS DECENT MASS CONVERGENCE ALONG
COLD FRONT WILL COMBINE WITH MODEST ELEVATED INSTABILITY...CAPES
AROUND 1500J/KG...SO IF CONVECTION IN IOWA IS ABLE TO BECOME MORE
ORGANIZED IT MAY HAVE ENOUGH SUPPORT TO MAINTAIN CONVECTIVE
COMPLEX...HOWEVER FORMING RIGHT ALONG THICKNESS RIDGE WILL HAVE SOME
UNCERTAINTY IN ITS FORWARD PROPAGATION. FRONT EXPECTED TO PUSH
THROUGH MUCH OF THE CWA BY WEDNESDAY MORNING WITH JUST LINGERING
CHANCES IN THE FAR SE CWA...TRENDING TOWARD A DRY FORECAST FOR THE
ENTIRE AREA BY AFTERNOON. WARM AND MUGGY CONDITIONS EXPECTED TONIGHT
FOR THE SE HALF WITH LOWS AROUND 70 WHILE FRONTAL PASSAGE WILL ALLOW
TEMPS TO DROP INTO THE MID 60S NW. COOLER AND LESS HUMID FOR
WEDNESDAY WITH HIGHS 75-80.
&&
.LONG TERM...(WEDNESDAY NIGHT THROUGH TUESDAY)
ISSUED AT 306 PM EDT TUE JUL 22 2014
COMFORTABLE/FAIR WX WILL PREVAIL WEDNESDAY NIGHT THROUGH FRIDAY
MORNING AS STABLE CANADIAN HIGH PRESSURE DROPS THROUGH. MID-UPPER
LEVEL FLOW WILL BRIEFLY TRANSITION TO A FLATTER/SEMI-ZONAL WNW
REGIME BY LATE FRIDAY INTO SATURDAY...WHILE IN THE LOW LEVELS WINDS
VEER MORE SOUTHERLY ALLOWING AN ACTIVE WARM FRONT TO WORK ENE INTO
THE REGION. LEAD/WEAK SHORTWAVE IN ADVANCE OF PRIMARY SHORTWAVE
TROUGH AND INCREASING MASS/MOISTURE CONVERGENCE ALONG THE DEVELOPING
FRONT SUPPORT INHERITED CHANCE POPS FOR SHOWERS/STORMS DURING THIS
TIME...MAINLY LATER FRIDAY NIGHT INTO SATURDAY.
RE-AMPLIFICATION OF EASTERN CONUS TROUGH REMAINS A CONSISTENT SIGNAL
IN MODEL GUIDANCE SUNDAY INTO EARLY NEXT WEEK. COLD FRONT ON LEADING
EDGE OF HEIGHT FALLS MAY SUPPORT ANOTHER ROUND OF CONVECTION LATER
SATURDAY NIGHT-SUNDAY DEPENDING ON TIMING. UNSEASONABLY COOL AND
MAINLY DRY WX LIKELY RETURNS EARLY NEXT WEEK.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z WEDNESDAY NIGHT)
ISSUED AT 112 AM EDT WED JUL 23 2014
TSRA WHICH DEVELOPED ALONG THE CDFNT THIS EVE MOVG INTO NWRN
INDIANA ATTM. WILL CONT TEMPO TSRA MENTION INTO FOR NEXT COUPLE OF
HOURS AT SBN... ALSO ADDED TSRA TO FWA FROM 07-09Z... THOUGH CONFIDENCE
NOT AS HIGH FOR THIS TERMINAL AS STORMS MOVING INTO AN AREA WITH
HIGHER CIN. CDFNT STILL EXPECTED TO MOVE THROUGH THE AREA EARLY
THIS MORNING WITH BRISK N-NW WINDS DEVELOPING BEHIND IT. SOME MVFR
CIGS BEHIND THE FRONT OVER NRN MI SHOULD MOVE THROUGH NRN INDIANA
DURING THE MORNING WITH CIGS SCATTERING OUT IN THE AFTN.
&&
.IWX WATCHES/WARNINGS/ADVISORIES...
IN...BEACH HAZARDS STATEMENT THROUGH THURSDAY MORNING FOR INZ003.
MI...BEACH HAZARDS STATEMENT THROUGH THURSDAY MORNING FOR MIZ077.
OH...NONE.
LM...SMALL CRAFT ADVISORY UNTIL 8 AM EDT THURSDAY FOR LMZ043-046.
&&
$$
SYNOPSIS...OBERGFELL
SHORT TERM...JAL
LONG TERM...STEINWEDEL
AVIATION...JT
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AREA FORECAST DISCUSSION
NWS INDIANAPOLIS IN
1237 AM EDT WED JUL 23 2014
.UPDATE...
THE AVIATION SECTION HAS BEEN UPDATED BELOW.
&&
.SYNOPSIS...
ISSUED AT 226 PM EDT TUE JUL 22 2014
THE CURRENT UPPER RIDGE BRIDGING FROM THE WEST ACROSS THE GREAT
LAKES WILL RETROGRADE WESTWARD. A SERIES OF MINOR LOW PRESSURE
TROUGHS TOP THE REBUILDING WESTERN US RIDGE TO REDEVELOP THE
EASTERN TROUGH NEXT WEEK. THIS MEANS A RETURN TO COOLER AND LESS
HUMID WEATHER.
AN INITIAL FRONTAL BOUNDARY WILL SWEEP ACROSS CENTRAL INDIANA
WEDNESDAY FOLLOWED BY RESORT LIKE HIGH PRESSURE FOR THURSDAY AND
FRIDAY. THE SERIES OF LOW PRESSURE SYSTEMS TOPPING THE RIDGE WILL
PRODUCE PERIODS OF THUNDERSTORM FRIDAY NIGHT INTO MONDAY OR
TUESDAY BEFORE ANOTHER DRY-OUT AND COOL DOWN WITH LOWS IN THE 50S
AND HIGHS IN THE 70S BY MID-WEEK NEXT WEEK.
&&
.NEAR TERM /TONIGHT/...
ISSUED AT 1050 PM EDT TUE JUL 22 2014
BASED ON EVENING CONVECTIVE/RADAR TRENDS AND HRRR GUIDANCE...HAVE
PUSHED POPS BACK SEVERAL HOURS AND LOWERED THEM. STRONGEST
CONVECTION ONGOING ACROSS LAKE MICHIGAN AND NORTHERN ILLINOIS
WHERE DYNAMICS ARE STRONGER. THIS ACTIVITY MAY BE ABLE TO EXPAND
ENOUGH TO IMPACT NORTHWESTERN FORECAST AREA LATER TONIGHT...BUT
THIS IS FAR FROM CERTAIN. PREVIOUS DISCUSSION FOLLOWS.
ISSUED AT 226 PM EDT TUE JUL 22 2014
ISSUE OF CONCERN IS STORM POTENTIAL TONIGHT. CURRENT WARM CAP ALOFT
MAY HELP INHIBIT WHATEVER CONVECTION DEVELOPS THIS EVENING OUT WEST.
COMBINED WITH OVERNIGHT STORM ARRIVAL AND STABILIZING TEMPS AND
STRONGEST FORCING REMAINING IN THE GREAT LAKES...EXPECT
DIMINISHING LINE OF STORMS/SHOWERS TO MOVE TO NEAR I-70 BY DAYBREAK
WEDNESDAY. WITH DEWPOINTS LIKELY TO CLIMB TO THE LOWER 70S AHEAD
OF THE FRONT...MIN TEMPS SHOULD BE NEAR 70 EXCEPT WHERE ANY HEAVY
DOWNPOURS DROP MINS TO UPPER 60S. WIDESPREAD RAIN IS UNCERTAIN BUT
LOCAL HALF INCH DOWNPOURS CAN BE EXPECTED WITH THE STRONGER
STORMS. SOME POTENTIAL FOR GUSTINESS WITH THESE STRONGER STORMS
BUT THESE SHOULD STAY BELOW SEVERE LIMITS.
&&
.SHORT TERM /WEDNESDAY THROUGH FRIDAY/...
ISSUED AT 226 PM EDT TUE JUL 22 2014
WEDNESDAY...ISSUE IS HOW LONG RAIN THREAT LINGERS AND POTENTIAL
FOR SEVERE. MODELS DIFFER SLIGHTLY ON TIMING BUT CLOSE ENOUGH TO
BLEND FOR GOOD FORECAST.
INITIAL THRUST OF CONVECTION SHOULD SAG SLOWLY SOUTH DURING
MORNING HOURS AHEAD OF WIND SHIFT/FRONTAL BOUNDARY. LOCATIONS
NORTHWEST OF A TERRE HAUTE TO MUNCIE LINE WILL LIKELY HAVE
ALREADY SEEN RAIN THREAT ENDED. SOUTH OF THERE...MORNING HEATING
WILL RENEW STORM COVERAGE AND STRENGTH IN OUR SOUTHERN COUNTIES.
GREATEST GROWTH IN COVERAGE AND STRENGTH...SUGGESTED BY ALL MODELS
WILL OCCUR SOUTH AND EAST OF OUR FORECAST AREA. STILL ENOUGH
ENERGY TO BUILD THAT LOCALIZED STRONG WIND GUSTS COULD OCCUR IN
OUR SOUTHERN MOST AREAS.
WEDNESDAY NIGHT INTO FRIDAY...
NO ISSUES THIS FORECAST PERIOD. CANADIAN HIGH PRESSURE BUILDS IN
AND DROPS DEWPOINTS BACK TO LOWER 50S...MIN TEMPS BACK INTO THE
MID AND UPPER 50S...AND MAX TEMPS BACK TO THE UPPER 70S AND LOWER
80S. FRONTAL BOUNDARY THAT DROPPED TO THE OHIO RIVER BEGINS
GETTING PULLED BACK NORTH AS LOW PRESSURE TRACKS INTO THE PLAINS
BRINGING A RETURN TO SOUTHWEST FLOW FRIDAY BUT NO STORMS BEFORE
FRIDAY NIGHT.
&&
.LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/...
ISSUED AT 138 PM EDT TUE JUL 22 2014
THERE IS A HIGH CONFIDENCE FORECAST WITH LITTLE REASON TO CHANGE THE
REGIONAL INITIALIZATION.
UNUSUALLY LARGE STRONG WEATHER PATTERNS FOR THIS TIME OF YEAR ARE
GOING TO PERSIST INTO NEXT WEEK. SUCH WELL DEFINED SYSTEMS ARE
RELATIVELY EASY FOR THE MODELS TO FORECAST. GIVEN THEIR FORECASTS
ARE CLOSE THERE IS A GOOD CHANCE THEY WILL WORK OUT.
FORECAST CONFIDENCE IS A LITTLE LOWER FOR SUNDAY AND SUNDAY NIGHT
THAN AT OTHER TIMES. THE REASON IS A FRONT WILL BE CROSSING THE
AREA...AND EVEN MINOR DIFFERENCES IN TIMING COULD HAVE A BIG
EFFECT ON THE SENSIBLE WEATHER.
&&
.AVIATION /DISCUSSION FOR THE 23/06Z TAFS/...
ISSUED AT 1237 AM EDT WED JUL 23 2014
VFR THROUGH THE PERIOD SAVE FOR POSSIBLE MVFR CONDITIONS IN ANY
SHOWERS...WHICH ARE TOO LOW PROBABILITY FOR INCLUSION...AND FOG AT
BMG WHICH MAY MAKE IT INTO IFR TERRITORY NEAR DAYBREAK.
IT NOW APPEARS SOMEWHAT LESS LIKELY THAT THUNDERSTORMS WILL IMPACT
THE TERMINALS AS INSTABILITY IS RELATIVELY WEAKER ACROSS THE AREA.
LATEST SHORT TERM MODELS SHOW CONVECTION WEAKENING AS WELL. WILL
BACK EVERYONE DOWN TO A VCSH MENTION.
FRONT WILL MOVE THROUGH AND WINDS WILL SWING TO THE NORTHWEST/NORTH
IN ITS WAKE TOMORROW...WITH ONLY SCATTERED FAIR WEATHER CUMULUS AND
SOME HIGH CLOUDS.
&&
.IND WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
SYNOPSIS...DT
NEAR TERM...DT/NIELD
SHORT TERM...DT
LONG TERM...JK
AVIATION...NIELD/50
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AREA FORECAST DISCUSSION
NWS GOODLAND KS
1200 AM MDT WED JUL 23 2014
.UPDATE...
ISSUED AT 552 PM MDT TUE JUL 22 2014
UPDATED TO REMOVE THE HEAT ADVISORY SINCE TEMPERATURES ARE ON THE
DECLINE.
&&
.SHORT TERM...(THIS EVENING THROUGH WEDNESDAY)
ISSUED AT 1255 PM MDT TUE JUL 22 2014
18Z WATER VAPOR IMAGERY INDICATED LARGE UPPER LEVEL RIDGE CENTERED
OVER NEW MEXICO WITH RUC ANALYSIS INDICATING A 600 DM RIDGE IN
PLACE AT H5. AT THE SFC...OUTFLOW BOUNDARY HAS STALLED ACROSS THE
EXTREME SOUTHERN CWA...BETWEEN TRIBUNE AND LEOTI EXTENDING
NORTHEAST TOWARDS HILL CITY.
MAIN CONCERNS FOR THE SHORT TERM WILL BE TEMPS AND PRECIP CHANCES
THIS EVENING AND TOMORROW AFTERNOON.
LACK OF ANY MEANINGFUL CU FIELD AT 19Z LOWERS OVERALL CONFIDENCE
IN LATE AFTERNOON THUNDERSTORM FORECAST AND WHILE AN ISOLATED
STORM IS STILL POSSIBLE...HAVE DOUBTS THAT ANYTHING WILL FIRE
ALONG REMAINING OUTFLOW BOUNDARY. WITH H85-H7 WAA INCREASING
TONIGHT...IT WILL BE POSSIBLE FOR STORMS COMING OUT OF THE
NORTHWEST TO MAINTAIN THEMSELVES BUT WITH WEAK WINDS THROUGHOUT
THE COLUMN STORM MOTION WOULD BE SLOW. A FEW MODELS SUGGEST
ELEVATED CONVECTION DEVELOPING AFTER 06Z AND WHILE THE FORCING
WILL BE THERE...CONDENSATION PRESSURE DEFICITS AND PRESSURE
ADVECTION VALUES ON 310 AND 315K SURFACES WOULD SUGGEST SATURATION
UNLIKELY. IF STORMS/CLOUDS CANNOT DEVELOP...BACKED EASTERLY FLOW
WITH A 100MB POCKET OF LOW LEVEL MOISTURE WOULD SUPPORT AT LEAST
PATCHY FOG PRIOR TO 15Z. GENERAL CONSENSUS OF MODELS SUGGESTS
TEMPERATURES AROUND 5 DEGREES COOLER ON WEDNESDAY THAN
TODAY...GIVEN EXPECTED SFC PATTERN THAT APPEARS REASONABLE.
.LONG TERM...(WEDNESDAY NIGHT THROUGH TUESDAY)
ISSUED AT 231 PM MDT TUE JUL 22 2014
A RIDGE OVER THE ROCKIES/PLAINS WILL SHIFT TO THE DESERT SOUTHWEST
BY FRIDAY. A SURFACE TROUGH WILL BE IN EASTERN COLORADO FROM
WEDNESDAY NIGHT UNTIL IT SHIFTS INTO SOUTHWEST KANSAS FRIDAY.
THE SURFACE TROUGH WILL FOCUS THUNDERSTORM DEVELOPMENT WEDNESDAY
EVENING. A SHORTWAVE MOVES INTO THE AREA WILL PROVIDE FORCING. CAPE
WILL RANGE FROM 1000 TO 2000J/KG AND SHEAR WILL BE 20KTS. FORECAST
SOUNDINGS INDICATE AN OVERALL LACK OF MID LEVEL MOISTURE SO WILL
CONTINUE SLIGHT CHANCE POPS.
FOR THURSDAY AFTERNOON AND EVENING, THE SURFACE TROUGH WILL BE
ORIENTED ACROSS NORTHWEST KANSAS BUT ONCE AGAIN FORECAST SOUNDINGS
SHOW HIGH BASED MOISTURE AROUND 600MB. CAPE RANGES FROM 200J/KG IN
EASTERN COLORADO TO 800J/KG IN THE EAST. DUE TO THESE MARGINAL
PARAMETERS WILL STAY WITH SLIGHT CHANCE POPS WITH COVERAGE OVER THE
ENTIRE FA AS THE TROUGH SHIFTS SOUTH DURING THE EVENING.
SURFACE CONVERGENCE AND HEATING WILL BE THE MAIN FORCING FRIDAY
AFTERNOON WITH THE TROUGH WELL TO THE SOUTH OF THE FA. STORMS SHOULD
INITIATE ON THE HIGHER TERRAIN IN EASTERN COLORADO WHERE LIFT WILL BE
MAXIMIZED. SLIGHT CHANCE POPS WILL CONTINUE FOR FRIDAY AFTERNOON.
MAX TEMPERATURES WILL REACH THE UPPER 90S THURSDAY AND FRIDAY. MIN
TEMPERATURES WILL COOL TO THE UPPER 60S WITH AROUND 70 IN THE EAST.
IN THE EXTENDED...(FRIDAY NIGHT THROUGH TUESDAY)...
THE RIDGE OVER THE SOUTHERN ROCKIES WITH SHIFT TO THE DESERT
SOUTHWEST BY SATURDAY AND CONTINUE THROUGH TUESDAY. THERE IS A
SLIGHT CHANCE OF THUNDERSTORMS FRIDAY/SATURDAY WITH STORMS
DEVELOPING DUE TO UPSLOPE WIND/SURFACE CONVERGENCE OVER THE HIGHER
TERRAIN IN EASTERN COLORADO. THESE STORMS WILL MOVE SLOWLY EAST
INTO NORTHWEST KANSAS. NUMEROUS WEAK DISTURBANCES IN NORTHWEST FLOW
WILL PROVIDE FORCING FOR AT LEAST A SLIGHT CHANCE/CHANCE OF
THUNDERSTORMS EACH DAY FROM SUNDAY THROUGH TUESDAY.
MIN TEMPERATURES WILL RANGE FROM 65 TO 70 FRIDAY AND SATURDAY NIGHTS
COOLING TO THE MID 60S SUNDAY AND MONDAY NIGHTS. MAX TEMPERATURES
WILL REACH THE MID 90S SATURDAY COOLING TO THE UPPER 80S FROM SUNDAY
THROUGH TUESDAY.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z WEDNESDAY NIGHT)
ISSUED AT 1157 PM MDT TUE JUL 22 2014
VFR CONDITIONS ARE EXPECTED AT MCK AND GLD THROUGH THE TAF PERIOD.
MCK MAY SEE SOME SHOWERS IN THE VICINITY BETWEEN 09Z-11Z AS THE
REMNANTS OF A THUNDERSTORM IN THE NEBRASKA PANHANDLE CONTINUES
SOUTHEASTWARD INTO NORTH CENTRAL KANSAS. ADDITIONALLY...THERE MAY
BE PATCHY FOG BETWEEN 11Z-13Z AT MCK. MCK AND GLD WITH OTHERWISE
SEE MOSTLY CLEAR SKIES WITH GENERALLY SOUTHEAST WINDS BECOMING
GUSTY DURING THE AFTERNOON HOURS ON WEDNESDAY.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
UPDATE...LOCKHART
SHORT TERM...JRM
LONG TERM...FS
AVIATION...LOCKHART
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
1210 AM CDT Wed Jul 23 2014
...Updated synopsis and aviation discussion...
.SYNOPSIS...
ISSUED AT 1205 AM CDT WED JUL 23 2014
At 00z Wednesday a 500mb high was centered over central Colorado
with an upper ridge axis extending north across the northern
Rockies. A 500mb low was located off the southwest coast of
British Columbia. A 300mb jet streak was located between the upper
high and upper low and extended from central California into Idaho.
A 700mb high was located over the Central High Plains and
temperatures varied from +12c at Omaha to +14c at Dodge City to
+17c at Denver. A 850mb cold front extended from northeast Wyoming
to southeast Nebraska at 00z Wednesday and the surface cold front
extended from northwest Kansas into northern Missouri.
&&
.UPDATE...
ISSUED AT 747 PM CDT TUE JUL 22 2014
Executing a bunch of superficial/minor tweaks... 1) will allow the heat
advisory to expire at 8 PM CDT. 2) feeble showers have tried to develop
across Rush county this evening, but are not developing vertically any
more. Looks very weak visually and have removed pops for this evening.
The HRRR suggests more convection, but this model is initializing poorly.
3) updated the HWO and EHWO. 4) running the usual ESTF grids to get
hourly t`s and sky grids in line with reality.
&&
.SHORT TERM...(This evening through Wednesday)
ISSUED AT 1234 PM CDT TUE JUL 22 2014
The upper level high pressure system over Colorado and New Mexico
will not be going anywhere over the next two days. A cold front was
draped south across northern Kansas late this morning, with a
surface low pressure system over eastern Colorado. The cold front
will sag slowly south today, and be just north of the I-70
interstate by 7 pm CDT. This front should serve as a convergence
zone, as well as will the trough near the Colorado border. We have
small 20 percent Pops in our west and northerly zones after 23z
today/tonight, extending in the north through about midnight. The
chances are small, but if any storm does break through the cap, they
will likely be high based and with mainly down burst, strong winds
as hazards. The surface is heating up nicely and highs today should
reach the forecasted maxes of 100 to 102F. I plan to keep the Heat
Advisory ongoing through 8 pm, as currently forecast, and will
update it shortly. The convective temp from the DDC 12Z RAOB
showed 98F. I Will brief the next shift on the high based storm
low chances and the main threat being down burst winds.
There will be a few clouds tonight, resulting in partly cloudy
skies. Minimum temperatures should be from near 70F in the west
along the Colorado border, to the mid 70s in the Coldwater and
Medicine lodge areas. Again, the small chances for thunderstorms
will continue through midnight in our northern counties.
The cold front will push south to near our southern border with
Oklahoma Wednesday. This should allow slightly cooler air and some
high level clouds to cover our CWA. Max temperatures will lower
from the past two days, into the mid 90s north of I-70 to the
upper 90s in our south along the Oklahoma border. Winds on
Wednesday should be from the east at 5 to 20 mph.
.LONG TERM...(Wednesday night through Tuesday)
ISSUED AT 342 PM CDT TUE JUL 22 2014
Upper level ridging will build back into the high plains region for
Thursday and into the weekend. With renewed surface troughing over
western Kansas, high temperatures ought to warm back to the high
90s, with possibly some readings over 100F. Little in the way of
thunderstorm activity is expected, although isolated thunderstorms
can`t be ruled out, particularly in far western Kansas with
elevated heating. The next cold front is expected to pass through
western Kansas by Saturday night as an upper level system over the
northwestern United States passes over the upper level ridge into
the Great Lakes. High temperatures ought to drop at least several
degrees by Sunday to the lower and mid 90s, and probably to around
90F by Monday and Tuesday. There will be small chances for
thunderstorms as the front passes and even behind the front into
Monday. A large upper level trough will persist over the upper
Midwest and Great Lakes regions through the remainder of next
week, resulting in a continued break from the hot temperatures.
There will be small chances for thunderstorms given the lack of
mid level capping; but it appears as though the upper level
pattern may be too amplified for sufficient lee troughing and
destabilization in the presence of the northwesterly mid to upper
level flow.
&&
.AVIATION...(For the 06Z TAFS through 06Z Wednesday night)
ISSUED AT 1205 AM CDT WED JUL 23 2014
VFR conditions are expected given that the 00Z NAM BUFR soundings
indicating limited mid to high level moisture will be present across
western Kansas as an upper high slowly moves east across Colorado
through late Wednesday. A weak cold front will move across western
Kansas early Wednesday morning. Winds at less than 10knots will
shift from the south to the northeast as this front passes. Light
northeast winds will then gradually veer to the southeast by late
day as a surface pressures begin to fall along the lee of the
Rockies and the surface ridge axis moves east towards Iowa and
Missouri.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 69 100 74 100 / 10 10 10 10
GCK 69 101 73 101 / 10 10 10 10
EHA 70 100 72 101 / 10 10 10 10
LBL 69 101 73 101 / 10 10 10 10
HYS 69 99 74 100 / 10 10 10 10
P28 71 99 74 100 / 10 10 10 10
&&
.DDC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...Sugden
SYNOPSIS...Burgert
SHORT TERM...Burke
LONG TERM...Finch
AVIATION...Burgert
AREA FORECAST DISCUSSION
NWS JACKSON KY
139 AM EDT WED JUL 23 2014
.UPDATE...
ISSUED AT 139 AM EDT WED JUL 23 2014
CONDITIONS ACROSS THE AREA REFLECT THE CURRENT FORECAST QUITE WELL.
PERHAPS SOME LESSENING OF THE CLOUD COVER IS IN ORDER AS THE MORE
WIDE SPREAD COVER IS STILL UP STREAM. OTHERWISE...THE CURRENT
FORECAST REMAINS ON TRACK AND HAVE UPLOADED THE CURRENT OBS INTO THE
GRIDS.
UPDATE ISSUED AT 1040 PM EDT TUE JUL 22 2014
THE SHOWERS HAVE DRIED UP ACROSS THE ENTIRE AREA BESIDES A SMALL CELL
OVER NORTHERN PULASKI COUNTY. THIS WILL DIMINISH THROUGH 11
PM...LEAVING MOSTLY CLEAR TO PARTLY CLOUDY SKIES OVERHEAD FOR THE
MAJORITY OF THE OVERNIGHT. EXPECT MOISTURE TO INCREASE BETWEEN 4 AND
8 AM...WITH PERHAPS A SMALL UPTICK IN CONVECTIVE ACTIVITY THREATENING
ALONG THE SOUTHEAST TERRAIN. THE LATEST HRRR IS SUGGESTING SOME
ACTIVITY MAKING IT IN FROM THE NORTHWEST BEFORE DAWN...HOWEVER THE
CONVECTIVE OUTCOME LOOKS A BIT QUICK ACCORDING TO THE LATEST
SATELLITE TRENDS...SO STUCK WITH THE INHERITED DRY POPS IN THE
BLUEGRASS FOR NOW. BALMY LOWS OF AROUND THE 70 DEGREE MARK FOR MOST
LOCATIONS STILL LOOK ON TARGET. DID INCORPORATE THE LATEST HOURLY
OBSERVATIONS INTO THE DIURNAL DROP OFF FOR THE REST OF THE NIGHT.
UPDATES HAVE BEEN SENT.
UPDATE ISSUED AT 817 PM EDT TUE JUL 22 2014
CONVECTION IS ON THE DECLINE WITH THE LOSS OF HEATING. WILL HANG ONTO
ISOLATED SHOWERS AND A RUMBLE OF THUNDER FOR ANOTHER HOUR OR TWO...
BEFORE A LULL IS THEN EXPECTED INTO THE OVERNIGHT. AS WEAKER
SOUTHWEST FLOW ENGAGES IN TH LOW LEVELS TOWARDS DAWN...THERE MAY BE A
SMALL INCREASE IN CONVECTION ONCE AGAIN...WHICH THE CURRENT FORECAST
ALREADY HAS WELL IN HAND. UPDATES HAVE BEEN SENT.
&&
.SHORT TERM...(THIS EVENING THROUGH WEDNESDAY NIGHT)
ISSUED AT 420 PM EDT TUE JUL 22 2014
AS OF LATE AFTERNOON...AN UPPER LEVEL LOW IS MEANDERING ALONG THE
GULF COAST WHILE THE EASTERN EXTENT OF AN UPPER LEVEL RIDGE CENTERED
NEAR THE FOUR CORNERS REGION EXTENDS INTO THE LOWER OH VALLEY REGION.
A SHORTWAVE IS ROTATING ACROSS THE NORTHERN GREAT LAKES AND ONTARIO
WITH ANOTHER UPSTREAM ENTERING NORTHWEST ONTARIO.
THE SHORTWAVES WILL COMBINE TO HELP FORM AN EASTERN CONUS TROUGH
THROUGH THE PERIOD WHILE THE RIDGE AMPLIFIES ACROSS THE ROCKIES. A
SFC LOW ASSOCIATED WITH THE DEVELOPING TROUGH WILL TRACK FROM JUST
NORTH OF THE NORTHERN GREAT LAKES AND INTO THE MARITIMES THROUGH WED
NIGHT WITH THE DEVELOPING TROUGH AND NORTHWEST FLOW PUSHING THE
TRAILING COLD FRONT INTO THE OH VALLEY LATE TONIGHT INTO THE DAY ON
WED. THIS FRONT WILL GRADUALLY CROSS THE REGION LATE ON WED AFTERNOON
INTO WED EVENING.
IN THE MEANTIME...ISOLATED SHOWERS AND POSSIBLY A STRAY THUNDERSTORM
WILL REMAIN POSSIBLE MAINLY UNTIL NEAR SUNSET AND DAYTIME HEATING IS
LOST. THERE WILL BE SOME MINOR HEIGHT FALLS OVERNIGHT AND WITH A
MOIST AIR MASS IN PLACE...A STRAY SHOWER CANNOT BE RULED OUT
OVERNIGHT...BUT THIS WOULD BE FEW AND FAR BETWEEN OTHERWISE...THE
CONSECUTIVELY DRIVEN CU SHOULD DISSIPATE OVERNIGHT AND PATCHY RIVER
VALLEY FOG IS AGAIN ANTICIPATED.
MORE ORGANIZED CONVECTION IS ANTICIPATED AS THE FRONT APPROACHES AND
CROSSES THE REGION AND THE UPPER LEVEL TROUGH DEVELOPS OVER THE
EASTERN CONUS. THIS FRONT AND UPPER LEVEL FORCING FROM THE DEVELOPING
TROUGH WILL INTERACT WITH A MOIST PREFONTAL AIR MASS TO BRING MORE
ORGANIZED CONVECTION TO THE REGION FROM WED AFTERNOON INTO WED NIGHT.
MORNING HEATING WILL BE DE PENDANT ON HOW MUCH CLOUD COVER THERE IS IN
THE AM AND THIS WILL ULTIMATELY DETERMINE INSTABILITY. MODERATE
INSTABILITY IS ANTICIPATED WITH TEMPS IN THE MID 80S TO AROUND 90 AND
DEWPOINTS IN THE UPPER 60S TO AROUND 70. THE LOW LEVEL GRADIENT WILL
BE RATHER WEAK AND SO WILL THE WINDS WHILE THE UPPER LEVEL WINDS WILL
NOT BE ALL THAT STRONG SO SHEAR WILL BE WEAK. PWS IS PROGGED TO CLIMB
1.5 TO 1.8 INCH RANGE FROM MIDDAY WED INTO WED NIGHT...SO STORMS
SHOULD BE ABLE TO PRODUCE LOCALLY HEAVY RAIN. A STRONGER STORM OR TWO
MIGHT ALSO BE ABLE TO PRODUCE STRONG WIND GUSTS. ONCE THE FRONT
CROSSES THE REGION...INSTABILITY WILL DIMINISH AND THE THREAT FOR
THUNDER SHOULD ALSO DIMINISH LATE WED NIGHT.
TEMPS WILL CONTINUE TO BE ABOVE NORMAL THROUGH THE PERIOD...BUT A
COLDER AND DRIER AIR MASS WILL ALREADY BE STARTING TO ADVECT INTO THE
AREA LATE IN THE PERIOD.
.LONG TERM...(WEDNESDAY NIGHT THROUGH MONDAY)
ISSUED AT 348 AM EDT TUE JUL 22 2014
THE MODELS ARE IN ONLY FAIR AGREEMENT ALOFT THROUGH THE EXTENDED
PORTION OF THE FORECAST. WHILE THEY ALL DEPICT THE ABNORMAL PATTERN
OF A STRONG FOUR CORNERS REGION RIDGE AND DEEP TROUGHING IN THE EAST
CONTINUING THROUGH THE END OF THE WEEK AND INTO THE START OF THE
NEXT WEEK...THEY DIFFER ON THE MAGNITUDE AND TIMING OF THE EVOLVING
EASTERN TROUGH...PARTICULARLY OVER THE WEEKEND AND INTO MONDAY.
SPECIFICALLY...FALLING HEIGHTS OVER KENTUCKY WILL BE THE RULE INTO
THURSDAY NIGHT AS THE RETROGRADING LOW TO THE SOUTH PULLS AWAY AND
THE NORTHERN STREAM SENDS A SERIES OF SHORTWAVES THROUGH THE AREA IN
NORTHWEST FLOW. THIS EASTERN TROUGH PULLS AWAY TO START THE WEEKEND
WITH HEIGHTS CLIMBING TEMPORARILY BEFORE THEY FALL AGAIN IN THE FACE
OF A NODE OF THE LARGE NORTHEAST TROUGH GEARING UP FOR A DIVE INTO
THE UPPER MIDWEST AND OHIO VALLEY. THE 00Z GFS IS MOST AGGRESSIVE
WITH THIS EVOLUTION WHILE THE 12 ECMWF KEEPS ITS CORE WAVE FURTHER
TO THE NORTHWEST AND LAGS THE GFS DEVELOPMENT. HOWEVER...THE LATEST
CMC AND ECMWF ARE TRENDING MORE TOWARD THE GFS. REGARDLESS...
NORTHWEST FLOW WILL DOMINATE THE LOCAL PATTERN AS HEIGHTS FALL INTO
MONDAY MORNING. EVENTUALLY...THE ECMWF CATCHES UP...WITH THE DEEPER
AND MORE WESTERN TROUGH IDEA OF THE GFS BUT SOME SIGNIFICANT
DIFFERENCES REMAIN WITH THE PATTERN OVER THE OHIO VALLEY TO CLOSE
OUT THE WEEK. THE BETTER AGREEMENT EARLIER IN THE EXTENDED SUPPORTS
A BLENDED SOLUTION WHILE THE LARGER SPREAD LATER ON LOWERS
CONFIDENCE SO THAT THE ENSEMBLES AND A SLIGHT LEAN TOWARD THE GFS
ARE PREFERRED SOLUTIONS.
SENSIBLE WEATHER WILL FEATURE AN APPROACHING COLD FRONT SERVING AS A
FOCUSING MECHANISM FOR SHOWERS AND THUNDERSTORMS WEDNESDAY NIGHT
INTO THURSDAY. COOLER AND DRIER AIR WILL FILTER INTO THIS PART OF
THE STATE LATER IN THE DAY THURSDAY PUTTING AN END TO THE CONVECTIVE
CHANCES FROM NORTHWEST TO SOUTHEAST. DRY AND RELATIVELY COOL WEATHER
FOLLOWS INTO THE START OF THE WEEKEND THANKS TO A BRIEF VISIT OF
HIGH PRESSURE. HOWEVER...THE COLD FRONT THAT BROUGHT THE DRIER
WEATHER WILL START TO SURGE NORTH OVER THE WESTERN PARTS OF THE
REGION AND BRING WARMTH...MOISTURE...AND BETTER CONVECTIVE CHANCES
BACK INTO THE AREA ON SATURDAY. A SERIES OF SHORT WAVES AT MID
LEVELS...THE DEVELOPING TROUGH...AND THE SFC FRONTAL STRUCTURE OVER
THE OHIO VALLEY KEEP SHOWER AND THUNDERSTORM CHANCES GOING INTO
SUNDAY AND MONDAY.
THE CR GRID LOAD PROVIDED A DECENT START TO THE FORECAST FOR THE
EXTENDED...THOUGH DID ADJUST THE POPS TO ADD A TINGE OF DIURNAL TO
THE TIMING OF THE CONVECTION. ALSO...TWEAKED THE LOW TEMPERATURE
GRIDS A TAD TO REFLECT RIDGE AND VALLEY DIFFERENCES WEDNESDAY AND
THURSDAY NIGHT.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z WEDNESDAY NIGHT)
ISSUED AT 139 AM EDT WED JUL 23 2014
SKIES ARE CLEARING OUT ACROSS THE AREA AND WITH SOUTHWESTERLY FLOW
BRINGING IN MOIST AIR...SOME FOG WILL DEVELOP IN THE MORNING HOURS.
TAF SITES SHOULD GO DOWN TO AT LEAST MVFR IF NOT SOME IFR TOWARDS
DAWN. JKL IS MORE LIKELY TO SOME VALLEY FOG ADVECTED IN ON STATION.
HEADING INTO THE DAY...CLOUD COVER WILL BE ON THE INCREASE AS A COLD
FRONT MOVES THROUGH. HAVE PUT THUNDER IN THE TAF SITES AND ON STATION
BY 19Z AS THE BEST CHANCE FOR THUNDERSTORMS WILL BE DURING THE
AFTERNOON TOWARDS THE EVENING WITH THE FRONT APPROACHING AS WELL.
MOST LOCATIONS SHOULD GO DOWN TO IFR CONDITIONS WITH THIS DURATION OF
PRECIP. CEILINGS SHOULD THEN BE IFR THROUGH THE REST OF THE TAF
PERIOD AS WELL. WINDS SHOULD BR LIGHT BUT INCREASE OUT OF THE WEST
WITH THE FRONT.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...SHALLENBERGER
SHORT TERM...JP
LONG TERM...GREIF
AVIATION...SHALLENBERGER
AREA FORECAST DISCUSSION
NWS TWIN CITIES/CHANHASSEN MN
338 AM CDT WED JUL 23 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 338 AM CDT WED JUL 23 2014
MOST IMPRESSIVE FEATURE ON THE H5 CHART LAST NIGHT WAS THE RIDGE
CENTERED OVER COLORADO...WHERE THE H5 HEIGHT MEASURED AT GRAND
JUNCTION REACHED THE LOFTY HEIGHT OF 6000 M. ITS ASSOCIATED RIDGE
AXIS EXTENDS NORTH INTO SASKATCHEWAN...WITH CONVERGENT NW FLOW NOTED
FROM MANITOBA INTO NW MN...HENCE THE 1028 MB SFC HIGH THAT IS
CENTERED OVER THE MANITOBA LAKES THIS MORNING. DURING THE SHORT
TERM...THE UPPER RIDGE WILL SHIFT EAST INTO THE UPPER MISS VALLEY
WHILE THE SFC HIGH WILL SHIFT OVER TO LAKE MICHIGAN BY 12Z THU.
FOR TODAY...NAM CU RULE SHOWS SCT-BKN CU FIELD DEVELOPING ACROSS WRN
WI...TRAILING OFF TO LITTLE IF ANY CU FOR WRN MN. HOWEVER...WRN MN
WILL HAVE TO DEAL WITH REMNANT CLOUD COVER FROM UPPER WAVES ROTATING
AROUND THE COLORADO RIDGE. IN PARTICULAR...THE RAP SHOWS THE WAVE
CURRENTLY OVER CENTRAL NODAK WORKING TOWARD WRN MN BY THE AFTERNOON.
DRY LOW LEVELS COURTESY THE 1028 MB HIGH WILL MAKE IT TOUGH TO GET
THE PRECIP IN THE MINOT AREA INTO MN...THOUGH A FEW SPRINKLES CAN
NOT BE COMPLETELY RULED OUT. DID BOOST SKY COVER WEST TO ACCOUNT FOR
THIS WAVE AND ITS ASSOCIATED CLOUD COVER THOUGH. H85 TEMPS WILL BE
FAIRLY UNIFORM AROUND 12/13C...WHICH HAS BEEN PRETTY GOOD THIS
SUMMER AT PRODUCING HIGHS IN THE 77 TO 81 DEGREE RANGE...SO NO BIG
CHANGES WERE NEEDED TO THE GOING FORECAST.
TONIGHT...AS THE RIDGE WORKS ACROSS WI...RETURN FLOW WILL BE
STRENGTHENING ACROSS THE DAKOTAS...WITH ISENTROPIC LIFT AND THETA-E
ADVECTION BOTH BLOSSOMING. LLJ ORIENTATION FAVORS ACTIVITY
DEVELOPING ALONG THE MO RIVER TONIGHT...MAKING ABOUT AS FAR EAST AS
SE SODAK...SO KEPT THE FORECAST DRY THROUGH 12Z THU...THOUGH WE
PROBABLY WILL NOT HAVE TO WAIT VERY LONG ON THU TO START SEEING
PRECIP PUSH INTO THE UPPER MN VALLEY. OVER WI...WITH THE HIGH
OVERHEAD THE QUESTION BECOMES HOW LOW TO GO...ALONG WITH THE
POTENTIAL FOR FOG. DID NUDGE LOWS DOWN A DEGREE OR TWO CLOSER TO THE
CONSENSUS RAW MODEL BLEND /BEST PERFORMING GUIDANCE OVER THE LAST
WEEK/...WHICH HAS LADYSMITH DIPPING INTO THE UPPER 40S. THE FOG
POTENTIAL IS A BIT TOUGHER TO PIN DOWN AT THIS POINT...BUT CERTAINLY
IF WE DO SEE LOWS DOWN AROUND 50...SOME PATCHY FOG...ESPECIALLY NEAR
BODIES OF WATER WILL CERTAINLY BE POSSIBLE.
.LONG TERM...(THURSDAY THROUGH TUESDAY)
ISSUED AT 338 AM CDT WED JUL 23 2014
SCATTERED SHOWERS AND THUNDERSTORMS ARE EXPECTED TO BE OVER
EASTERN DAKOTAS AT DAYBREAK ON THURSDAY ALONG AND AHEAD OF A
STRENGTHENING BAROCLINIC ZONE STRETCHING NW-SE ACROSS THE NORTHERN
PLAINS. THE SHOWERS AND THUNDERSTORMS WILL SPREAD ACROSS THE MN
CWA DURING THE DAY AND INTO WESTERN WI BY EVENING AS THE
FRONTOGENETIC ZONE MOVES EAST. THE FA IS IN THE RIGHT ENTRANCE REGION
OF AN 80 PLUS KNOT JET SEGMENT ACROSS THE WESTERN GREAT LAKES
WITH UPPER LEVEL DIVERGENCE INDICATED. BY THE END OF THE DAY...A
COUPLED JET STRUCTURE BEGINS TO DEVELOP...ALONG WITH INCREASING
DIVERGENCE...AS THE LEFT EXIT REGION OF A NEW SEGMENT ARRIVES FROM
THE EASTERN DAKOTAS. THIS FEATURE THEN PASSES ACROSS SOUTHERN
AREAS OF MN AND IA THURSDAY NIGHT. WHILE THIS IS OCCURRING...LOW
LEVEL MOISTURE TRANSPORT IN THE CENTRAL PLAINS VEERS INTO IA AND
SOUTHERN MN. THIS SHOULD RESULT IN THUNDERSTORMS INCREASING IN
COVERAGE ACROSS THE AFOREMENTIONED AREAS ALONG WITH THE POTENTIAL
FOR HEAVY RAIN. THE ECMWF HAS A GREAT HANDLE ON THIS SITUATION
WHILE OTHER DETERMINISTIC MODELS STRUGGLE TO DEVELOP MUCH
PRECIPITATION...WHICH IS A CHARACTERISTIC OF WARM AIR ADVECTION
EVENTS. HENCE...CHANCE POPS DURING THE DAY THURSDAY INCREASE TO
LIKELY THURSDAY NIGHT ACROSS SOUTHERN AREAS OF MN.
THE PRECIPITATION WILL MOVE ESE FRIDAY MORNING WITH A DRYING TREND
FRIDAY AFTERNOON AS A FAIRLY STRONG SHORT WAVE MOVES THROUGH.
HOWEVER...A WEAK SURFACE FRONT WILL SLOWLY TRAVERSE THE FA FRIDAY
AFTERNOON AND NIGHT WITH SOME SMALL POPS REMAINING. MUCH OF
SATURDAY LOOKS DRY BEFORE A COMPACT VERTICALLY STACKED LOW
PRESSURE SYSTEM SWINGS SOUTHEAST ACROSS THE UPPER MISSISSIPPI
VALLEY REGION SATURDAY NIGHT AND SUNDAY. THIS NECESSITATES MORE
CHANCE POPS FOR THE LATTER HALF OF THE WEEKEND. HIGHS FROM
THURSDAY TO SATURDAY WILL BE SLOWLY RISING FROM AROUND 80 TO THE
LOWER AND MIDDLE 80S RESPECTIVELY. HIGHS WILL THEN TREND DOWN INTO
THE MIDDLE TO UPPER 70S FOR SUNDAY AND AT LEAST THE FIRST HALF OF
NEXT WEEK. THE REASON FOR THE EXTENDED COOL DOWN IS A DEEPENING
EASTERN NORTH AMERICA TROUGH WITH A BUILDING RIDGE IN THE WEST.
LONGER RANGE MODEL SOLUTIONS HAVE BEEN VERY CONSISTENT ON THIS
DEVELOPMENT WITH A H5 CLOSED LOW JUST NORTH OF THE GREAT LAKES
NEXT WEDNESDAY. H5 HEIGHTS ACROSS THE GREAT LAKES AND OHIO VALLEY
ARE FORECAST TO BE 2 TO 3 STANDARD DEVIATIONS BELOW NORMAL.
ACCOMPANYING THE COOLER TEMPERATURES WILL BE MAINLY DRY CONDITIONS.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z WEDNESDAY NIGHT)
ISSUED AT 1041 PM CDT TUE JUL 22 2014
VFR CONDS XPCTD AT ALL SITES WITH NO IMPACTS. N WINDS AOB 10 KT
XPCTD THROUGHOUT THE DURATION OF THE 06Z TAFS. SKC CONDS
OVERNIGHT FOLLOWED BY A RETURN OF SCT MIDLVL CU CLOUDS BY MIDDAY
TMRW.
KMSP...NO SIGNIFICANT IMPACTS XPCTD THROUGHOUT THIS TAF SET
DURATION.
/OUTLOOK FOR KMSP/
THU...VFR. WINDS SE AT 10KTS.
THU NGT...VFR. MVFR CONDITIONS/TSRA POSSIBLE. WINDS SE 10 KNOTS.
FRI...VFR. MVFR CONDITIONS TSRA. WINDS SSE AT 10-15KTS.
FRI NGT...VFR. MVFR CONDITIONS IN SCT TSRA. WINDS S/SE AT 5-8KTS.
SAT...VFR. WINDS W/NW AT 10-15KTS.
&&
.MPX WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...NONE.
&&
$$
SHORT TERM...MPG
LONG TERM...RAH
AVIATION...JPC
AREA FORECAST DISCUSSION
NWS KANSAS CITY/PLEASANT HILL MO
1224 AM CDT Wed Jul 23 2014
.DISCUSSION...
Issued at 333 PM CDT TUE JUL 22 2014
Mid to upper 90s prevailing across much of the region this afternoon
as the warmest airmass of the season continues to grip the area.
Latest 850-mb analysis from the SPC meso site showing the 28C temp
contour directly over the fcst region this afternoon. This combined
with steep low-level lapse rates and dewpoints largely in the lower
to middle 70s has resulted in a very hot and oppressive day across
the area. Current heat advisory for the entire fcst area needs no
adjustments and is set to expire at 7 PM this evening.
In addition to the heat...the other main concern remains focused on
possible severe convection later this evening as main cold front now
found over southwestern IA and eastern NE continues to slowly track
south with time. For what its worth...high-res convection allowing
models struggled mightily with this mornings convection across
our northeastern zones...and very little guidance from these models
appears to be in the offering for activity later this evening as
well. Not surprisingly...overall confidence for tonight/s fcst is
less than desired as some models show developing convection...while
others such as the HRRR continue to backtrack towards a drier and
drier fcst with each successive run. So here/s what we know so far...
Sfc boundary set to arrive towards the IA/MO state line around 00z
this evening. Out ahead of this feature...airmass remains capped with
a significant amount of inhibition thanks that 700-mb temps ranging
in the 12-14C range. Additionally...northerly 925-850-mb winds will
provide little if any low-level convergence into the arriving
frontal boundary as we continue into the evening hrs. Despite
this...quick look at latest water vapor imagery does show an inbound
shortwave trough now seen over south-central NE and north-central
KS. This feature combined with very modest frontal convergence may be
enough to get this going...however concerns for widespread severe
remain marginal as of this writing. Latest SPC day 1 outlook has
trimmed the SLGT risk mention further to the southeast...which is
more in line with where convection may develop as front continues to
drop south. That said...main severe threat with any activity that
forms will likely be strong wind gusts as nearly dry adiabatic lapse
rates will support favorable low-level and boundary layer mixing.
High wet-bulb zero heights (>16 kft) will likely negate the threat
for very large hail until later on when any lingering activity begins
to go elevated with due to loss of daytime heating. Overall concerns
for hail though remain the lowest of the two forms of severe outlined
above however. In general...severe threat this evening looks to be
isolated with the most likely areas to possibly see a rogue storm or
two residing in our northeastern zones where better potential exists
to break the cap thanks to slightly cooler temps aloft. If activity gets
going...severe threat should transition south of the I-70 corridor as
front continues to make progress through the area. As mentioned above
through...a widespread severe event does not look to be in the
offering this evening.
Region should largely reside in a post frontal airmass
tomorrow...with weak dry air advection allowing for cooler and less
humid conditions. In fact...fcst models suggest dewpoints anywhere
between 5-10 degrees cooler than today...which should be a welcomed
relief following today/s oppressive conditions. High temps should
round out in the middle to upper 80s.
Large scale pattern shift expected from Thursday into Friday as southern
Plains ridge retrograde west as northern stream energy traverses the
northern Rockies/Plains. As this occurs...upper flow will become
decidedly more northwesterly which will set the stage for unsettled
conditions heading into the upcoming weekend. Closer to the
surface...fcst models still paint a northward retreating warm front
by late week as return flow reestablishes itself across the Great
Plains in advance of lee side troughing along the Front Range. Several
upper shortwaves embedded in northwest flow will allow for continued
chances for showers and storms through at least Saturday...if not
Sunday. As is the case with convection this time of year...hard to
pin your hat on any one feature of interest as long range models to
include both the ECMWF and GFS normally suffer from convective
feedback issues to some degree. As a result...have maintained Chc
pops through the weekend before high pressure arrives by early next
week following the passage of a cold front on Sunday. Temps early
next week look to fall below normal with highs possibly only reaching
into the lower to middle 80s come Monday and Tuesday.
&&
.AVIATION...(For the 06Z TAFS through 06Z Wednesday Night)
Issued at 1224 AM CDT WED JUL 23 2014
VFR conds will cont thru the TAF period. A few-sct clouds around
3-4kft will affect the terminals thru the first couple hours of the
TAF period otherwise expect just few-sct high cirrus clouds. Winds
will be out of the NNE around 10kts through this evening before
veering to the ENE and diminishing to btn 5-10kts.
&&
.EAX WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
MO...NONE.
&&
$$
DISCUSSION...32
AVIATION...73
AREA FORECAST DISCUSSION...UPDATED AVIATION
NWS ST LOUIS MO
1158 PM CDT Tue Jul 22 2014
.SHORT TERM: (Through Late Tonight)
Issued at 330 PM CDT Tue Jul 22 2014
There is a considerable amount of uncertainty in the convective
evolution and coverage tonight. Dew points in the 70s, strong
heating and steep mid level lapse rates are currently contributing
to SBCAPE of 3500-6000 j/kg across the northwest 2/3rds of the CWA
with the highest values across central and north central MO. There
also is a significant cap in place due to warm mid level temperatures.
The big question is when and how much of the cap will be reduced
as the front moves southward out of Iowa and southeast Nebraska
into northern MO this evening. Model solutions including the
convection allowing models are quite varied on QPF and implied
coverage. Recent runs of the HRRR are quite stingy on coverage
with isolated storms at best. I don`t have a great feel for what
is going to occur, but the deterministic models suggest that height
falls/cooling aloft should be sufficient to weaken the cap and
allow for scattered development along front, mainly late this
evening and especially overnight. I have attempted to follow this
trend with the greatest coverage along/east of the MS river. The
severe threat is conditional on development early enough this
evening to realize the big CAPE, and the main threat would appear
to be damaging winds given the warm air aloft.
Glass
.LONG TERM: (Wednesday through Next Tuesday)
Issued at 330 PM CDT Tue Jul 22 2014
The cold front should lie roughly from south central IL to near
St. Louis into southwest MO at 12z and exit the CWA by early
afternoon. There will continue to be a threat of scattered showers
and storms ahead of the advancing front. Temperatures should be
cooler tomorrow with the main thrust of cooling and drying in the
afternoon. Unseasonably deep upper troffing in the eastern U.S.
will keep a large surface high dominating the area Wednesday night
into Friday, with most of this period dominated by lower humidity
and below average temperatures.
Beginning late Thursday night and into Friday the threat of precipitation
will return in association with elevated showers/thunderstorms due to
strong warm advection/moisture transport via a southwesterly LLJ ahead
of the slowly retreating warm front and in association with impulses
aloft dropping southeastward along the eastern periphery of the
upper high. A cold front will then drop through the area Saturday
afternoon-Sunday as a upper trof digs southeastward from the upper
MS valley and into the Great Lakes bringing another threat of
showers and thunderstorms. This upper wave will be part of large
scale amplification of the upper air pattern across NOAM and will
feature another deep trof over the eastern U.S. through the first
part of next week and send out July with another period of below
average temperatures.
Glass
&&
.AVIATION: (For the 06z TAFs through 06z Wednesday Night)
Issued at 1147 PM CDT Tue Jul 22 2014
TSTMs have struggled to maintain vs a strong cap this evening.
don`t expect much to change overnight with isld activity
continuing thru the night. Removed prevailing thunder group
completely from KCOU and KUIN and changed to VCTS at STL metro
sites at a later time. Band of CIGS near 2.5kft has dvlpd just
behind the front...as indicated by the models...across nthrn MO
and on into cntrl/nthrn IL. Expect this to follow the front south
overnight and possibly expand some. MVFR fog is also possible
towards mrng with a moist bndry lyr in place. Otherwise...expect
diurnal cu and N/NNE winds aob 12kts.
Specifics for KSTL:
Coverage for TSTMs has been minimal this evng as the convection
struggles to survive against a strong cap...so have a VCTS group
to cover the threat. A band of post frontal high end MVFR CIGs
has dvlpd across nthrn IL and cntrl IL. This should push S in
concert with the front. Otherwise...expect diurnal cu and a N/NNE
wind aob 12kts.
2%
&&
.LSX WATCHES/WARNINGS/ADVISORIES:
MO...NONE.
IL...NONE.
&&
$$
WFO LSX
AREA FORECAST DISCUSSION
NWS BUFFALO NY
224 AM EDT WED JUL 23 2014
.SYNOPSIS...
AS A COLD FRONT WILL CROSS MUCH OF THE CWA THIS MORNING AND BE SOUTH
AND EAST OF MUCH OF THE AREA BY LATER THIS AFTERNOON. THE HUMID AIR
WILL KEEP THE WARM AND MUGGY CONDITIONS IN PLACE ACROSS THE AREA FOR
THE REMAINDER OF THE OVERNIGHT. THEN EXPECT A ROUND SHOWERS AND
SCATTERED THUNDERSTORMS AS THE COLD FRONT CROSSES THE REGION FROM
NORTHWEST TO SOUTHEAST WEDNESDAY. COOLER AND DRYER WEATHER WILL
FOLLOW THIS COLD FRONT. EXPECT COMFORTABLE CONDITIONS WITH TEMPS
AVERAGING A BIT BELOW NORMAL THROUGH THE END OF THE WEEK.
&&
.NEAR TERM /THROUGH TODAY/...
SURFACE HIGH PRESSURE CENTERED OFF THE MID ATLANTIC COAST AND LOW
PRESSURE PASSING NORTH OF THE GREAT LAKES WILL MAINTAIN A WARM
AND HUMID SSW BREEZE ACROSS THE REGION OVERNIGHT. THIS WILL KEEP IT
FEEL RATHER MUGGY...WITH LOWS IN THE UPPER 60S TO LOWER 70S.
A LINE OF CONVECTION HAS CONSOLIDATED NICELY ACROSS SOUTHWESTERN
ONTARIO...STRETCHING ROUGHLY FROM TORONTO SOUTHWESTWARD ALONG THE
NORTHERN SHORELINE OF WESTERN LAKE ERIE. LINE IS PROGRESSING
EASTWARD AT A PRETTY SLOW PACE...SO DID NOT MAKE ANY CHANGES TO POPS
AT THIS TIME. IF THIS LINE HOLDS TOGETHER MAY SEE A SHOWER OR
THUNDERSTORM ACROSS THE NIAGARA FRONTIER BY DAWN OR A LITTLE
THEREAFTER.
THE HRRR ALONG WITH THE NAM12/RGEM APPEAR TO SHOW A REASONABLE
PROGRESSION FOR THIS LINE...WITH MOST OF THE RAINFALL WILL HAVE
CROSSED THE FORECAST AREA BEFORE NOONTIME...FOLLOWED SHORTLY
THEREAFTER BY THE COLD FRONT. HEAVIEST RAINS SHOULD FALL MID TO LATE
MORNING...PROBABLY NORTHEAST OF THE LAKES WHERE A MOIST PRE-
FRONTAL SW FLOW WILL CLASH WITH THE NW WINDS BEHIND THE FRONT. HIGH
DEWPOINTS AND 8KFT TO 10KFT DEPTH OF MOISTURE WILL YIELD
PRECIPITABLE WATER VALUES RANGING FROM 1.6 TO 1.8 INCH AND THE
GREATEST OMEGA IS WITHIN THE LOWER MOIST LAYER...INDICATING
EXCLUSIVE WARM RAIN PROCESS AND THE POTENTIAL FOR SOME DOWNPOURS.
THE COLD FRONT CROSSES THE REGION DURING THE EARLY AFTERNOON WITH
MUCH DRIER AIR BY THE END OF THE DAY.
HIGH TEMPS MAY RECOVER A COUPLE OF DEGREES IN THE MORNING WITH
READINGS IN THE MID TO UPPER 70S.
&&
.SHORT TERM /TONIGHT THROUGH FRIDAY NIGHT/...
THE COLD FRONT WILL BE PUSHING TO THE EAST COAST WEDNESDAY EVENING
WITH THE LAST FEW LINGERING SHOWERS ACROSS CENTRAL NEW YORK
TAPERING OFF BEFORE MIDNIGHT. A COOLER AND DRIER AIRMASS WILL BUILD
IN BEHIND THE FRONT THROUGH THE END OF THE WEEK. LINGERING MOISTURE
FROM RAIN EARLIER WEDNESDAY MAY BRING SOME PATCHY FOG LATER
WEDNESDAY NIGHT MAINLY ACROSS THE SOUTHERN TIER AND NORTH COUNTY
OTHERWISE TEMPS WILL FALL INTO THE 50S EXCEPT ALONG THE LAKESHORES
AND IN URBAN AREAS.
THURSDAY THROUGH FRIDAY HIGH PRESSURE WILL SHIFT ACROSS NEW YORK
BRINGING VERY COMFORTABLE TEMPERATURES AND HUMIDITY A FEW DEGREES
BELOW AVERAGE. (HIGHS IN THE 70S AND LOWS IN THE 50S) DIURNAL
CUMULUS WILL SPROUT UP THURSDAY AS OVERNIGHT MOISTURE MIXES OUT
ALONG WITH A LIGHT NORTHERLY BREEZE. THURSDAY NIGHT MAINLY CLEAR SKIES
AND LIGHT WINDS WILL BRING RIVER VALLEY FOG ACROSS THE SOUTHERN TIER
OTHERWISE MAINLY CLEAR SKIES. ON FRIDAY MORE IN THE WAY OF DRYING
WILL KEEP MAINLY SUNNY SKIES WITH SOME HIGH CIRRUS WORKING IN FROM
THE WEST AHEAD OF A CENTRAL GREAT LAKES SYSTEM. OVERALL VERY
PLEASANT WEATHER TO CLOSE OUT THE WEEK.
&&
.LONG TERM /SATURDAY THROUGH TUESDAY/...
OVER THE WEEKEND INTO THE START OF NEXT WEEK AN AMPLIFYING EAST
COAST 500MB TROUGH FORECASTED BY THE MEDIUM RANGE MODELS WILL BRING
BACK A THREAT OF SOME SHOWERS AND THUNDERSTORMS WHILE KEEPING
TEMPERATURES NEAR TO A FEW DEGREES BELOW AVERAGE. QUITE A BIT OF
UNCERTAINTY IS PRESENT FOR SATURDAYS FORECAST WITH MODELS NOT IN
ALIGNMENT ON THE INITIAL UPPER LOW DROPPING ACROSS THE GREAT LAKES.
THE 12Z GFS IS FASTEST BRINGING IN SHOWERS BY SATURDAY AFTERNOON
WHILE OTHER MODELS DELAY THIS. HAVE INTRODUCED A SLIGHT CHANCE OF
SHOWERS ON SATURDAY ACROSS WNY BUT OVER ALL FEEL THE DAY WILL END UP
BEING DRY.
BETTER AGREEMENT DEVELOPS BY SUNDAY INTO MONDAY WHERE MODELS SHIFT
SEVERAL SHORTWAVES THROUGH THE UPPER TROUGH WITH EACH OF THESE
BRINGING A THREAT FOR SHOWERS AND THUNDERSTORMS. HAVE FEATURED THE
HIGHEST POPS ON MONDAY WHERE THE BEST MODEL ALIGNMENT IS FOUND IN
THE 500MB PATTERN WITH THE TROUGH CENTERED ACROSS THE GREAT LAKES.
TUESDAY THE CENTER OF THE TROUGH LOOKS TO BE OVER NEW YORK WITH A
CHANCE OF DIURNAL INSTABILITY SHOWERS. THIS UPPER TROUGH WILL KEEP
HIGH TEMPS LIMITED TO THE LOW TO MID 70S NEXT WEEK WHERE WE
TYPICALLY WOULD EXPECT NEAR 80.
&&
.AVIATION /07Z WEDNESDAY THROUGH SUNDAY/...
EXPECT MAINLY VFR CONDITIONS OVERNIGHT...WITH INCREASING CLOUDS
AHEAD OF A FRONTAL BOUNDARY. THERE MAY BE A FEW SHOWERS OR TSTMS
NEAR BUF/IAG TOWARD DAYBREAK...WITH WIDESPREAD SHOWERS AND
THUNDERSTORMS LIKELY TO HOLD OFF UNTIL THE MORNING HOURS WEDNESDAY.
THIS MAY RESULT IN LOCALIZED CONDITIONS OF LOWER CEILINGS AND LOCALLY
HEAVY DOWNPOURS...HOWEVER THE MAJORITY OF THE MORNING IS LIKELY TO
REMAIN VFR. AFTER THIS...MVFR CIGS ARE LIKELY TO BUILD BEHIND THE
FRONT WEDNESDAY AFTERNOON AND EVENING IN THE NW FLOW. SOME OF THE
LATEST GUIDANCE IS SUGGESTING THAT MOISTURE IN THE LOWER AND MID
LEVELS MAY REMAIN HIGH INTO TONIGHT BEHIND THE COLD FRONT. WILL TAKE
A CLOSER LOOK AT THIS AND ADJUST CLOUD COVER AND CEILINGS
ACCORDINGLY IF NEEDED.
OUTLOOK...
WEDNESDAY NIGHT...MAINLY VFR...PATCHY IFR/MVFR CIGS AND FOG POSSIBLE.
THURSDAY...VFR.
THURSDAY NIGHT THROUGH SATURDAY...MAINLY VFR...SAVE FOR IFR/MVFR
IN PATCHY SOUTHERN TIER VALLEY FOG LATER EACH NIGHT/EARLY EACH
MORNING.
SUNDAY...VFR/MVFR SCATTERED SHOWERS.
&&
.MARINE...
AREA OF HIGH PRESSURE WILL CONTINUE TO SLIP EASTWARD AND ALLOW FOR A
COLD FRONT TO CROSS THE LAKES ON WEDNESDAY. WINDS WILL INCREASE IN
SPEED AHEAD OF THE COLD FRONT THROUGH THE REMAINDER OF THE
OVERNIGHT...AND BECOME SSW. CONDITIONS MAY BRIEFLY APPROACH SMALL
CRAFT CRITERIA ON LAKE ERIE VERY LATE TONIGHT INTO WEDNESDAY MORNING
IN THIS FLOW. BEHIND THE COLD FRONT...WAVES 2 TO 3 FEET WILL BE
POSSIBLE ON BOTH LAKES WEDNESDAY NIGHT AND INTO THURSDAY. WINDS WILL
LESSEN THURSDAY AFTERNOON AND WAVES WILL DIMINISH ACCORDINGLY.
&&
.BUF WATCHES/WARNINGS/ADVISORIES...
NY...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...JM
NEAR TERM...APFFEL/JM/WCH
SHORT TERM...SMITH
LONG TERM...SMITH
AVIATION...APFFEL/JM
MARINE...APFFEL/JM/WCH
AREA FORECAST DISCUSSION
NWS WILMINGTON OH
207 AM EDT WED JUL 23 2014
.SYNOPSIS...
AN APPROACHING COLD FRONT WILL CONTINUE TO KEEP SOUTHWEST WINDS
AND HUMID AIR OVER THE OHIO VALLEY AHEAD OF IT. THIS FRONT WILL
PUSH THROUGH THE REGION WEDNESDAY AND SPARK A ROUND OF SHOWERS
AND THUNDERSTORMS. A LARGE AREA OF HIGH PRESSURE WILL BUILD BEHIND
IT AND PROVIDE DRY AND COOL WEATHER THROUGH THE END OF THE WORK WEEK.
&&
.NEAR TERM /UNTIL 6 AM THIS MORNING/...
DIURNAL CU HAVE DISSIPATED ACROSS THE AREA WITH SKIES CURRENTLY
MOSTLY CLEAR. WE SHOULD SEE AN INCREASE IN HIGH AND MID LEVEL
CLOUDS AS WE HEAD INTO THE OVERNIGHT HOURS AS A COLD FRONT
APPROACHES FROM THE NORTHWEST. A NARROW LINE OF SHOWERS AND
THUNDERSTORMS CURRENTLY ALONG THE FRONT STRETCHING FROM SOUTHERN
WISCONSIN INTO LOWER MICHIGAN WILL CONTINUE TO WORK ITS WAY
SOUTHEAST TOWARD OUR AREA OVERNIGHT. THE HRRR CONTINUES TO SUGGEST
THAT SOME OF THIS COULD MAKE IT DOWN INTO OUR NORTHWEST FA THROUGH
THE EARLY MORNING HOURS...WHILE THE ARW AND NMM WEAKEN AND
DISSIPATE THE STORMS AS THEY MOVE INTO OUR AREA. WILL CONTINUE WITH
SOME LOWER CHANCE POPS ACROSS THE NORTHWEST TO ACCOUNT FOR THE
POSSIBILITY...BUT WITH DECREASING INSTABILITIES...DO EXPECT A
GENERAL WEAKENING TREND TO ANY THUNDERSTORMS THAT DO MAKE IT INTO
OUR FA.
&&
.SHORT TERM /6 AM THIS MORNING THROUGH THURSDAY NIGHT/...
COLD FRONT IS BEING PROGGED WITH A CONTINUOUSLY FASTER SOLUTION
WITH EACH MODEL RUN. IN THE NW CWA AT 12Z IT IS WELL SOUTHEAST OF
THE I-71 CORRIDOR BY 18Z. PRECIP IN THE COLD POOL BEHIND THE WIND
SHIFT WILL BE HARD PRESSED TO SEE DAMAGING WINDS WITH ANY
CONVECTIVE ELEMENTS AND THE SWODY2 OUTLOOK APPEARS TO WHITTLE AWAY
AT THE SEVERE PROSPECTS WITH EACH DISCUSSION. AT THIS MOMENT...I
WOULD EXPECT A RAINY PERIOD WITH THUNDER BUT THE LACK OF DISTINCT
STRONG CORES/UPDRAFTS NECESSARY FOR WIND/HAIL. ELEVATED
INSTABILITY WILL MAKE FOR OCCASIONAL DOWNPOURS AND WINDS WHEN
THESE ELEVATED CORES COLLAPSE...BUT THE EXPECTED HIGH MOISTURE AND
COLD NATURE OF THE AIR IN THE BOUNDARY LAYER WOULD LIMIT ANY VERY
STRONG WINDS FROM OCCURRING.
HIGHS WERE PROGGED TO BE A BIT WARMER THAN I WOULD EXPECT IN THE
SOUTHEAST WITH A GRUNGY DAY OF CLOUD COVER. LOWERED READINGS A BIT
TO TOP OUT AT 90 DEGREES AS A MAXIMUM AND THINK THAT THIS WOULD BE
AN EARLY AFTERNOON HIGH WITH STRONG ADVECTION FROM A SUNNY POCKET
OVER KY BEING PULLED INTO MY NRN KY AND SERN OH COUNTIES. NW CWA
WILL BE THOROUGHLY GRUNGED AND NOT REACH PAST THE 70S.
AFTER PRECIP ENDS TOMORROW NIGHT...HIGH PRESSURE WILL PUSH IN
DRIER AND COOLER AIR TO THE OHIO VALLEY AND THIS WILL REMAIN IN
PLACE THROUGH THE END OF THE WORK WEEK.
&&
.LONG TERM /FRIDAY THROUGH TUESDAY/...
SURFACE HIGH PRESSURE WILL BE CENTERED ACROSS THE OHIO VALLEY ON
FRIDAY. THIS HIGH WILL QUICKLY SLIDE SOUTHEAST OF OUR REGION AND
WEAKEN AS AN UPPER LEVEL DISTURBANCE EMBEDDED IN NORTHWESTERLY
FLOW APPROACHES OUR REGION. MODELS HAVE ACCELERATED THE ARRIVAL OF
THIS DISTURBANCE...YET STILL VARY BY SEVERAL HOURS ON THEIR
FORECAST ARRIVAL OF PRECIPITATION ON SATURDAY. ADDED LOW CHANCE
POPS EARLY SATURDAY MORNING WITH POPS RAMPING UP INTO THE DAY
SATURDAY BASED ON THE FASTER TREND. KEPT ONLY CHANCE POPS ON
SATURDAY DUE TO TIMING AND COVERAGE UNCERTAINTIES FOR
PRECIPITATION ON SATURDAY. TEMPERATURES UNDER THE HIGH ON FRIDAY
WILL REMAIN A FEW DEGREES BELOW NORMAL. ONCE THE HIGH SHIFTS TO
OUR SOUTHEAST...A REBOUND TO NEAR NORMAL TEMPERATURES CAN BE
EXPECTED FOR SATURDAY.
ON SUNDAY...A UNSEASONABLY DEEP TROUGH IS EXPECTED TO DIG
SOUTHEASTWARD ACROSS THE MID WEST AND INTO THE OHIO VALLEY. LOW
PRESSURE DOWNSTREAM OF THIS TROUGH WILL DRAG A COLD FRONT ACROSS OUR
AREA. THE CMC AND GFS ARE IN FAIRLY GOOD AGREEMENT ON BRINGING
ENHANCED CHANCES FOR PRECIPITATION TO OUR AREA ON SUNDAY AHEAD OF
THIS FRONT...WITH THE COLD FRONT CROSSING OUR AREA AT SOME POINT
LATE SUNDAY. BEST CHANCES FOR PRECIPITATION APPEAR TO BE DURING THE
DAY SUNDAY IN THE WARM SECTOR...WITH COOLER AIR MOVING INTO THE
REGION BY MONDAY. THE TROUGH IS FORECAST TO REMAIN IN THE REGION
THROUGH THE EARLY PARTS OF NEXT WEEK. MODELS VARY ON HOW MUCH
MOISTURE LINGERS BEHIND THE FRONT. AM FORECASTING MAINLY LOW CHANCE
DIURNALLY DRIVEN SHOWERS AND ISOLATED THUNDERSTORMS IN THE COLD
SECTOR. THIS HIGH AMPLITUDE TROUGH WILL BRING ANOTHER ROUND OF WELL
BELOW NORMAL TEMPERATURES TO THE OHIO VALLEY EARLY NEXT WEEK...WITH
CURRENT INDICATIONS BEING THAT HIGHS MAY ONLY REACH THE LOWER 70S ON
MONDAY AND POSSIBLY AGAIN ON TUESDAY.
&&
.AVIATION /05Z WEDNESDAY THROUGH SUNDAY/...
A STRONG COLD FRONT WILL DROP DOWN FROM THE NORTHWEST TODAY AND
PUSH ACROSS THE TAF SITES LATE THIS MORNING INTO EARLY AFTERNOON.
LATEST RADAR MOSAIC SHOWS CONVECTION ALONG AND AHEAD OF THIS FRONT
PUSHING INTO NORTHWEST OHIO. THESE STORMS WILL MOVE SE PUSHING INTO
TAF SITES EARLY THIS MORNING. INSTABILITY WILL BE DECREASING...SO
STORMS EXPECTED TO WEAKEN AND DIMINISH IN COVERAGE. EXPECT MID/HIGH
LEVEL CLOUDS TO INCREASE AHEAD OF THIS FRONT. PRIOR TO THIS INCREASE
IN CLOUDS SOME FOG AND MVFR VSBY RESTRICTION WILL BE PSBL AT
KLUK...KILN AND KLCK. HAVE A MENTION OF VCTS FOR THIS INITIAL
POTENTIAL OF THUNDERSTORMS EARLY. BETTER THUNDERSTORM CONVERGE
EXPECTED TO DEVELOP ALONG THE FRONT AS MODERATE INSTBY DEVELOPS
THIS AFTN. THE BEST CHANCE FOR THIS LOOKS TO BE ALONG AND SE OF
I-71. HAVE A MENTION OF SHOWERS WITH VCTS TO ACCOUNT FOR FROPA
INTO MID AFTERNOON. EXPECT WINDS TO SHIFT TO THE NORTHWEST AND
THEN NE WITH VFR CONDITIONS THIS EVENING.
OUTLOOK...THUNDERSTORMS POSSIBLE SATURDAY AND SUNDAY.
&&
.ILN WATCHES/WARNINGS/ADVISORIES...
OH...NONE.
KY...NONE.
IN...NONE.
&&
$$
SYNOPSIS...FRANKS
NEAR TERM...JGL
SHORT TERM...FRANKS
LONG TERM...LATTO
AVIATION...AR
AREA FORECAST DISCUSSION
NWS TULSA OK
1140 PM CDT TUE JUL 22 2014
.AVIATION...
CONCERNING TAF SITES KTUL/KRVS/KBVO/KMLC/KXNA/KFYV/KFSM.
CONVECTION IS EXPECTED TO INCREASE IN COVERAGE POSSIBLY LATER
TONIGHT AND/OR TUESDAY AFTERNOON. THIS WILL BE ASSOCIATED WITH A
WEAKENING FRONTAL BOUNDARY AS IT SETTLES INTO THE REGION. PATCHY
LIGHT FOG WILL ALSO BE POSSIBLE TONIGHT...OTHERWISE VFR CONDITIONS
ARE EXPECTED TO PREVAIL OUTSIDE OF ANY STRONGER CONVECTION.
&&
.PREV DISCUSSION... /ISSUED 921 PM CDT TUE JUL 22 2014/
..UPDATE...
DISCUSSION...
TEMPS IN THE UPPER 70S TO UPPER 80S REMAINED COMMON ACROSS EASTERN
OKLAHOMA AND NORTHWEST ARKANSAS THIS EVENING. HEAT INDICES HAVE
ALSO COME DOWN SOME WITH VALUES IN THE RANGE FORM THE MID 80S TO
MID 90S STILL BEING REPORTED OVER NORTHEAST OKLAHOMA. TO THE NORTH
OF THE CWA...A WEAK COLD FRONT REMAINED POSITIONED ACROSS NORTHERN
KANSAS AND NORTHERN MISSOURI. THIS FRONT IS EXPECTED TO SAG
SOUTHWARD OVERNIGHT AND MOVE INTO THE FAR NORTHERN PART OF THE CWA
WEDNESDAY MORNING. LATEST RUNS OF THE LOCAL IN-HOUSE MODEL AS
WELL AS THE HRRR TRY TO DEVELOP THUNDERSTORMS ALONG/AHEAD OF THE
FRONT AND PUSH THEM INTO NORTHEAST OKLAHOMA AND NORTHWEST ARKANSAS
ALONG AN OUTFLOW BOUNDARY LATE TONIGHT. THE HRRR RUNS SAYS THAT
THERE SHOULD ALREADY BE ONGOING CONVECTION ACROSS CENTRAL
KANSAS...THROUGH LOOKING AT LATEST SATELLITE DATA...THERE SEEMS BE
LITTLE IN THE WAY OF CLOUD COVER. THE CAP OVER THE REGION LOOKS TO
BE NOT QUITE AS STRONG COMPARED TO OVER KANSAS THIS EVENING AND
THIS COULD ALLOW FOR SOME THUNDERSTORM ACTIVITY LATE TONIGHT TO
DEVELOP AND MOVE INTO THE CWA. THUS...WILL KEEP A SLIGHT CHANCE
POP OVER PARTS OF NORTHEAST OKLAHOMA INTO NORTHWEST ARKANSAS LATE
TONIGHT. THE BETTER CHANCES LOOK TO BE DURING THE DAY WEDNESDAY AS
THE FRONT ENTERS THE CWA AND INTERACTS WITH DAYTIME
HEATING/INSTABILITY. EVENING UPDATE WILL BE TO TWEAK POPS/WX A BIT
OTHERWISE THE REST OF THE FORECAST SEEMS TO BE HANDLING WELL.
EVEN WITH THE WEAK FRONT MOVING THROUGH THE REGION...HOT AND HUMID
CONDITIONS STILL LOOK POSSIBLE OVER THE REGION...ESPECIALLY SOUTH
OF THE BOUNDARY. WILL KEEP THE CURRENT HEAT HEADLINES AS IS.
&&
.PRELIMINARY POINT TEMPS/POPS...
TUL 76 98 72 94 / 10 30 10 0
FSM 73 96 72 93 / 20 50 20 10
MLC 71 95 72 96 / 10 20 20 10
BVO 71 95 68 94 / 10 30 10 0
FYV 68 90 67 88 / 20 50 20 10
BYV 69 90 65 86 / 20 50 10 10
MKO 72 96 71 94 / 20 30 10 10
MIO 72 92 68 91 / 20 50 10 10
F10 73 96 72 94 / 10 20 10 10
HHW 71 95 74 96 / 10 10 20 10
&&
.TSA WATCHES/WARNINGS/ADVISORIES...
OK...EXCESSIVE HEAT WARNING UNTIL 8 PM WEDNESDAY FOR OKZ060.
HEAT ADVISORY FROM 1 PM WEDNESDAY TO 8 PM WEDNESDAY FOR OKZ054-
OKZ055-OKZ056-OKZ059-OKZ061-OKZ062-OKZ064-OKZ065-OKZ066-
OKZ067-OKZ068-OKZ070-OKZ071-OKZ072-OKZ074.
AR...NONE.
&&
$$
AVIATION...07
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
554 AM EDT WED JUL 23 2014
.SYNOPSIS...
A COLD FRONT WILL PUSH SOUTHEAST ACROSS THE COMMONWEALTH LATE
TODAY AND TONIGHT. A REFRESHING...COOLER AND LESS HUMID AIRMASS
WILL OVERSPREAD THE COMMONWEALTH FOR THE END OF THE WEEK INTO THE
WEEKEND.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
WEAK RIDGING OVER THE REGION AT THE SURFACE AND ALOFT...COMBINED
WITH VERY WARM MID LEVEL TEMPS OF 9-11C WILL KEEP CONDITIONS
MAINLY CLEAR BUT MUGGY INTO THE LATE MORNING HOURS.
CURRENT DEWPOINTS IN THE MID TO UPPER 60S ARE A FEW DEG SHY OF
THE EXPECTED MIN TEMPS AROUND SUNRISE.
CIRRUS BLOWOFF FROM A WEAKENING LINE OF SHOWERS AND THUNDERSTORMS
OVER LAKE ERIE WILL OVERSPREAD THE NW MTNS THIS MORNING...BUT
THEN DISSIPATE FOR THE MIDDAY HOURS BEFORE NEW CONVECTION
INITIATES ALONG/AHEAD OF AN APPROACHING COLD FRONT.
THE BKN LINE OF SHRA/TSRA SLIDING SE ACROSS CENTRAL LAKE ERIE ATTM
IS OVER LOCALLY COOLER AND MORE STABLE LLVLS...AND IS PROGGED BY
THE LAST FEW RUNS OF THE HRRR TO STEADILY WEAKEN...AND EVEN
DISSIPATE AS IT MOVES ONTO THE SOUTH SHORE DURING THE NEXT
FEW HOURS AND ENCOUNTERS THE VERY STRONG MID-LEVEL CAP ACROSS
NWRN PENN. 15-MINUTE LIGHTNING FREQUENCY HAS DROPPED OFF
DRAMATICALLY OVER THE PAST HOUR. STILL PAINTED CHC POPS FOR
SHOWERS OR A RUMBLE OF THUNDER ACROSS NW WARREN COUNTY AROUND 12Z
SINCE EARLIER RUNS OF THE HRRR HAD NO SIGN OF CONVECTION EVEN
REACHING THE CENTRAL WATERS OF LAKE ERIE ATTM.
A DRY START TO THE DAY AND MAINLY SUNNY SKIES ACROSS ALL BUT THE
FAR NW ZONES...WILL GIVE WAY TO INCREASING CHANCES FOR SHOWERS
AND THUNDERSTORMS THIS AFTERNOON AS LARGE SCALE FORCING INCREASES
ASSOCIATED WITH THE APPROACHING COLD FRONT.
SPC HAS MAINTAINED A /SEE TEXT/ FOR ALL OF PENN WITHIN THEIR DAY
1 CONVECTIVE OUTLOOK...WITH EASTERN NEW YORK AND NEW ENGLAND UNDER
THE GUN FOR A SLIGHT RISK OF SVR TSRA GIVEN THE BETTER COMBINATION
OF STRONGER DEEP LAYER SHEAR AND CAPE. STILL...MODERATE-HIGH SFC
BASED CAPE IN EXCESS OF 2000 J/KG...COMBINED WITH ABOUT 20 KTS OF
0-6KM BULK SHEAR SHOULD BE SUFFICIENT FOR A FEW OCCURRENCES OF
DAMAGING MICROBURSTS AND HAIL ACROSS THE CWA THIS AFTERNOON INTO
THIS EVENING.
THE LOW-LEVEL...WSW DOWNSLOPE FLOW/COMPRESSIONAL WARMING OF THE
AIRMASS AHEAD OF THE CFRONT...WILL LEAD TO THE HIGHEST TEMPS OF
THE WEEK. AFTERNOON MAX TEMPS WILL RANGE FROM THE LOWER 80S
ACROSS THE HIGH TERRAIN OF THE NORTH AND WEST...TO THE MID AND
UPPER 80S IN THE CENTRAL VALLEYS...AND LOWER 90S IN THE GREATER
YORK/HARRISBURG AREA.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 AM THURSDAY/...
THE FOCUS FOR SHOWERS AND THUNDERSTORMS /SOME WITH HEAVY
RAIN...GUSTY WINDS...FQT LIGHTNING AND EVEN SOME FAIRLY LARGE
HAIL/ WILL OCCUR ACROSS THE LOWER SUSQ VALLEY THIS EVENING...
WHILE THE FAR NW SEES SHOWERS DECREASE/MOVE OFF TO THE SOUTH AS
THE CFRONT PUSHES THROUGH THE KBFD AREA LATE THIS AFTERNOON...AND
REACHES THE CENTRAL ZONES AOB 00Z THUR. SCATTERED SHOWERS AND A
STRAY TSRA WILL LINGER ACROSS THE CENTRAL RIDGE AND VALLEY REGION
THROUGH EARLY THIS EVENING.
24-HOUR...STORM TOTAL RAINFALL WILL BE ABOUT 4-5 TENTHS OF AN
INCH...WITH THE BULK OF IT FALLING FROM JUST ONE OR TWO
THUNDERSTORMS. GIVEN THE ANOMALOUSLY HIGH PWATS OF 1.5-2 INCHES
ACROSS THE STATE...THERE IS A CHANCE FOR LOCALLY HEAVY RAINFALL OF
OVER 1 INCH.
TEMPS TONIGHT WILL STILL BE QUITE MUGGY IN THE SOUTHEAST. LOWS
WILL RANGE FROM THE UPPER 60S ACROSS THE LOWER SUSQ REGION...TO
THE MUCH MORE COMFORTABLE UPPER 50S ACROSS THE NORTHERN MTNS.
&&
.LONG TERM /THURSDAY THROUGH TUESDAY/...
OVERALL SCENARIO REMAINS UNCHANGED IN THE LONG TERM PERIOD AS A
LARGE UPPER RIDGE BUILDING OVER THE FOUR CORNERS REGION IS
FORECAST TO EXPAND NORTH AND EAST INTO THE ROCKIES AND PLAINS
DURING THE PERIOD. DOWNSTREAM...THIS WILL LEAD TO LONG WAVE
TROFFING OVER THE EASTERN THIRD OF THE COUNTRY. UPPER LOW TO THE
EAST OF HUDSON BAY WILL BE STRENGTHENED AT TIMES BY SHORTWAVE
ENERGY IN THE STRONGER JET STREAM FLOW ACROSS CANADA. SOUTHWARD
EXTENSION OF THIS LOW/TROF WILL AT TIMES DURING THE PERIOD
STRENGTHENING THE TROFFING ACROSS THE NORTHEASTERN U.S./OUR
REGION. THE TREND OF MEDIUM RANGE MODEL GUIDANCE IS FOR
STRONGER/DEEPER TROFFING DOWNSTREAM ACROSS THE EASTERN
U.S...DEVELOPING AN ALMOST FULL LATITUDE TROF EXTENDING FROM THE
EASTERN CANADA LOW SWD TO FLORIDA. THIS WILL LIKELY SERVE TO
EXPAND AND PROLONG THE CHANCES FOR PCPN THIS WEEKEND.
GUIDANCE FORECASTS CONTINUE TO BRING A FRONT AND INCREASED
CHANGES FOR PRECIPITATION TOWARD PA IN THE WEDNESDAY/THURSDAY TIME
FRAME AND SHOW A SECOND...POTENTIALLY STRONGER SYSTEM LATE NEXT
WEEKEND. THE TREND OF STRONGER TROUGHING MENTIONED ABOVE HAS LEAD
TO SLOWER ARRIVAL AND DEPARTURE OF THE FRONTAL SYSTEM IN THE DAILY
PROGS. THE ECMWF IN LATEST RUN HAS SLOWED UP THE PROGRESSION OF
THIS UPPER LEVEL LOW...WHERE THE GFS OPERATIONAL AND ENSEMBLES
HAVE SPED UP ITS PROGRESSION THROUGH THE GREAT LAKES REGION. A
WARM FRONT WILL BE ON THE DOORSTEP OF PA SUNDAY...AS THE EC
CONTINUES TO SLOW ITS PROGRESSION SO EXPECT THE WARM FRONT TO MOVE
IN CLOSER TO MIDDAY SUNDAY. HAVE THUS ADJUSTED POPS/TIME.
ASSOCIATED COLD FRONT DOES NOT CROSS THE STATE TIL MONDAY...WHERE
SURPRISINGLY AT THIS POINT...THE EC AND GFS COME CLOSELY IN PHASE.
THIS LARGE UPPER LEVEL LOW COULD BECOME QUASI STATIONARY OVER
SOUTHERN CANADA...GREAT LAKES REGION WHICH COULD LEAD TO A
POTENTIAL PROLONGED PERIOD OF SHOWERS AND THUNDERSTORM THROUGH THE
MIDDLE OF NEXT WEEK.
&&
.AVIATION /09Z WEDNESDAY THROUGH SUNDAY/...
23/09Z...UPDATE...IR STLT/SFC OBS DEPICT SIGNIFICANTLY LESS FOG/ST
IMPACTING TERMINALS THAN IN RECENT MORNINGS. RADAR SHOWS LINE OF
STORMS CROSSING LK ERIE HAS WEAKENED CONSIDERABLY AS PREV FCST
BELOW. A SECOND LINE OF SCT SHOWERS RECENTLY DEVELOPED NEAR AFJ-
DUJ LINE AND SHOULD ALSO WEAKEN AS THEY APPROACH THE LAURELS BY 12Z.
23/06Z...CUT BACK ON FOG THIS MORNING GIVEN OBS TRENDS AND LGT
S-SW GRADIENT SFC WIND IN ADVANCE OF COLD FRONT SEWD ACRS LWR MI
TWD THE ERN LKS. LINE OF STORMS IN ADVANCE OF COLD FRONT MOVG ACRS
LK ERIE ARE FCST BY COSPA/HRRR/SPC 4KM WRF TO WEAKEN OR DISSIPATE
AS THEY REACH NW PA AROUND DAYBREAK.
AFTER SOMEWHAT OF A LULL IN CONVECTION DURING THE MID TO LATE
MORNING...EXPECT SCT TO NMRS SHWRS AND TSTMS TO DEVELOP FROM THIS
AFTN INTO THE EVE ALONG AND AHEAD OF THE COLD FRONT..AS IT SHIFTS
SEWD ACRS THE AIRSPACE. CVRG SHOULD BE GREATEST OVER THE CNTRL AND
ERN PRTNS OF THE AIRSPACE WITH SOME STG TO LCLY SVR STORMS
POSSIBLE. PREVAILING CONDS WILL VFR WITH BRIEF MVFR-IFR VIS
REDUCTIONS IN TSRA IMPACTS. WND SHIFT FROM SW TO NW BY TONIGHT
WITH MAIN PCPN ACTIVITY BCMG CONFINED TO SERN AREAS INTO THU.
POST-FRONTAL MVFR SEEMS PROBABLE OVER WRN SXNS TNGT.
OUTLOOK...
THU...SCT TSTM IMPACTS PSBL SERN AIRFIELDS AS COLD FRONT SLOWS
ALONG THE MID-ATLC COAST.
FRI...PATCHY MORNING FOG...OTHERWISE VFR/NO SIG WX.
SAT...PATCHY MORNING FOG...OTHERWISE VFR. ISOLD PM TSTM PSBL.
SUN...TSTM IMPACTS LKLY AS WARM FRONT LIFTS NWD ACRS AIRSPACE.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...LAMBERT
NEAR TERM...LAMBERT
SHORT TERM...LAMBERT
LONG TERM...LAMBERT/CERU
AVIATION...STEINBUGL
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
537 AM EDT WED JUL 23 2014
.SYNOPSIS...
A COLD FRONT WILL PUSH SOUTHEAST ACROSS THE COMMONWEALTH LATE
TODAY AND TONIGHT. A REFRESHING...COOLER AND LESS HUMID AIRMASS
WILL OVERSPREAD THE COMMONWEALTH FOR THE END OF THE WEEK INTO THE
WEEKEND.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
WEAK RIDGING OVER THE REGION AT THE SURFACE AND ALOFT...COMBINED
WITH VERY WARM MID LEVEL TEMPS OF 9-11C WILL KEEP CONDITIONS
MAINLY CLEAR BUT MUGGY INTO THE LATE MORNING HOURS.
CURRENT DEWPOINTS IN THE MID TO UPPER 60S ARE A FEW DEG SHY OF
THE EXPECTED MIN TEMPS AROUND SUNRISE.
CIRRUS BLOWOFF FROM A WEAKENING LINE OF SHOWERS AND THUNDERSTORMS
OVER LAKE ERIE WILL OVERSPREAD THE NW MTNS THIS MORNING...BUT
THEN DISSIPATE FOR THE MIDDAY HOURS BEFORE NEW CONVECTION
INITIATES ALONG/AHEAD OF AN APPROACHING COLD FRONT.
THE BKN LINE OF SHRA/TSRA SLIDING SE ACROSS CENTRAL LAKE ERIE ATTM
IS OVER LOCALLY COOLER AND MORE STABLE LLVLS...AND IS PROGGED BY
THE LAST FEW RUNS OF THE HRRR TO STEADILY WEAKEN...AND EVEN
DISSIPATE AS IT MOVES ONTO THE SOUTH SHORE DURING THE NEXT
FEW HOURS AND ENCOUNTERS THE VERY STRONG MID-LEVEL CAP ACROSS
NWRN PENN. 15-MINUTE LIGHTNING FREQUENCY HAS DROPPED OFF
DRAMATICALLY OVER THE PAST HOUR. STILL PAINTED CHC POPS FOR
SHOWERS OR A RUMBLE OF THUNDER ACROSS NW WARREN COUNTY AROUND 12Z
SINCE EARLIER RUNS OF THE HRRR HAD NO SIGN OF CONVECTION EVEN
REACHING THE CENTRAL WATERS OF LAKE ERIE ATTM.
A DRY START TO THE DAY AND MAINLY SUNNY SKIES ACROSS ALL BUT THE
FAR NW ZONES...WILL GIVE WAY TO INCREASING CHANCES FOR SHOWERS
AND THUNDERSTORMS THIS AFTERNOON AS LARGE SCALE FORCING INCREASES
ASSOCIATED WITH THE APPROACHING COLD FRONT.
SPC HAS MAINTAINED A /SEE TEXT/ FOR ALL OF PENN WITHIN THEIR DAY
1 CONVECTIVE OUTLOOK...WITH EASTERN NEW YORK AND NEW ENGLAND UNDER
THE GUN FOR A SLIGHT RISK OF SVR TSRA GIVEN THE BETTER COMBINATION
OF STRONGER DEEP LAYER SHEAR AND CAPE. STILL...MODERATE-HIGH SFC
BASED CAPE IN EXCESS OF 2000 J/KG...COMBINED WITH ABOUT 20 KTS OF
0-6KM BULK SHEAR SHOULD BE SUFFICIENT FOR A FEW OCCURENCES OF
DAMAGING MICROBURSTS AND HAIL ACROSS THE CWA THIS AFTERNOON INTO
THIS EVENING.
THE LOW-LEVEL...WSW DOWNSLOPE FLOW/COMPRESSIONAL WARMING OF THE
AIRMASS AHEAD OF THE CFRONT...WILL LEAD TO THE HIGHEST TEMPS OF
THE WEEK. AFTERNOON MAX TEMPS WILL RANGE FROM THE LOWER 80S
ACROSS THE HIGH TERRAIN OF THE NORTH AND WEST...TO THE MID AND
UPPER 80S IN THE CENTRAL VALLEYS...AND LOWER 90S IN THE GREATER
YORK/HARRISBURG AREA.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 AM THURSDAY/...
THE FOCUS FOR SHOWERS AND THUNDERSTORMS /SOME WITH HEAVY
RAIN...GUSTY WINDS...FQT LIGHTNING AND EVEN SOME FAIRLY LARGE
HAIL/ WILL OCCUR ACROSS THE LOWER SUSQ VALLEY THIS EVENING...
WHILE THE FAR NW SEES SHOWERS DECREASE/MOVE OFF TO THE SOUTH AS
THE CFRONT PUSHES THROUGH THE KBFD AREA LATE THIS AFTERNOON...AND
REACHES THE CENTRAL ZONES AOB 00Z THUR. SCATTERED SHOWERS AND A
STRAY TSRA WILL LINGER ACROSS THE CENTRAL RIDGE AND VALLEY REGION
THROUGH EARLY THIS EVENING.
24-HOUR...STORM TOTAL RAINFALL WILL BE ABOUT 4-5 TENTHS OF AN
INCH...WITH THE BULK OF IT FALLING FROM JUST ONE OR TWO
THUNDERSTORMS. GIVEN THE ANOMALOUSLY HIGH PWATS OF 1.5-2 INCHES
ACROSS THE STATE...THERE IS A CHANCE FOR LOCALLY HEAVY RANFALL OF
OVER 1 INCH.
TEMPS TONIGHT WILL STILL BE QUITE MUGGY IN THE SOUTHEAST. LOWS
WILL RANGE FROM THE UPPER 60S ACROSS THE LOWER SUSQ REGION...TO
THE MUCH MORE COMFORTABLE UPPER 50S ACROSS THE NORTHERN MTNS.
&&
.LONG TERM /THURSDAY THROUGH TUESDAY/...
OVERALL SCENARIO REMAINS UNCHANGED IN THE LONG TERM PERIOD AS A
LARGE UPPER RIDGE BUILDING OVER THE FOUR CORNERS REGION IS
FORECAST TO EXPAND NORTH AND EAST INTO THE ROCKIES AND PLAINS
DURING THE PERIOD. DOWNSTREAM...THIS WILL LEAD TO LONG WAVE
TROFFING OVER THE EASTERN THIRD OF THE COUNTRY. UPPER LOW TO THE
EAST OF HUDSON BAY WILL BE STRENGTHENED AT TIMES BY SHORTWAVE
ENERGY IN THE STRONGER JET STREAM FLOW ACROSS CANADA. SOUTHWARD
EXTENSION OF THIS LOW/TROF WILL AT TIMES DURING THE PERIOD
STRENGTHENING THE TROFFING ACROSS THE NORTHEASTERN U.S./OUR
REGION. THE TREND OF MEDIUM RANGE MODEL GUIDANCE IS FOR
STRONGER/DEEPER TROFFING DOWNSTREAM ACROSS THE EASTERN
U.S...DEVELOPING AN ALMOST FULL LATITUDE TROF EXTENDING FROM THE
EASTERN CANADA LOW SWD TO FLORIDA. THIS WILL LIKELY SERVE TO
EXPAND AND PROLONG THE CHANCES FOR PCPN THIS WEEKEND.
GUIDANCE FORECASTS CONTINUE TO BRING A FRONT AND INCREASED
CHANGES FOR PRECIPITATION TOWARD PA IN THE WEDNESDAY/THURSDAY TIME
FRAME AND SHOW A SECOND...POTENTIALLY STRONGER SYSTEM LATE NEXT
WEEKEND. THE TREND OF STRONGER TROUGHING MENTIONED ABOVE HAS LEAD
TO SLOWER ARRIVAL AND DEPARTURE OF THE FRONTAL SYSTEM IN THE DAILY
PROGS. THE ECMWF IN LATEST RUN HAS SLOWED UP THE PROGRESSION OF
THIS UPPER LEVEL LOW...WHERE THE GFS OPERATIONAL AND ENSEMBLES
HAVE SPED UP ITS PROGRESSION THROUGH THE GREAT LAKES REGION. A
WARM FRONT WILL BE ON THE DOORSTEP OF PA SUNDAY...AS THE EC
CONTINUES TO SLOW ITS PROGRESSION SO EXPECT THE WARM FRONT TO MOVE
IN CLOSER TO MIDDAY SUNDAY. HAVE THUS ADJUSTED POPS/TIME.
ASSOCIATED COLD FRONT DOES NOT CROSS THE STATE TIL MONDAY...WHERE
SURPRISINGLY AT THIS POINT...THE EC AND GFS COME CLOSELY IN PHASE.
THIS LARGE UPPER LEVEL LOW COULD BECOME QUASI STATIONARY OVER
SOUTHERN CANADA...GREAT LAKES REGION WHICH COULD LEAD TO A
POTENTIAL PROLONGED PERIOD OF SHOWERS AND THUNDERSTORM THROUGH THE
MIDDLE OF NEXT WEEK.
&&
.AVIATION /09Z WEDNESDAY THROUGH SUNDAY/...
23/06Z...CUT BACK ON FOG THIS MORNING GIVEN OBS TRENDS AND LGT
S-SW GRADIENT SFC WIND IN ADVANCE OF COLD FRONT SEWD ACRS LWR MI
TWD THE ERN LKS. LINE OF STORMS IN ADVANCE OF COLD FRONT MOVG ACRS
LK ERIE ARE FCST BY COSPA/HRRR/SPC 4KM WRF TO WEAKEN OR DISSIPATE
AS THEY REACH NW PA AROUND DAYBREAK.
AFTER SOMEWHAT OF A LULL IN CONVECTION DURING THE MID TO LATE
MORNING...EXPECT SCT TO NMRS SHWRS AND TSTMS TO DEVELOP FROM THIS
AFTN INTO THE EVE ALONG AND AHEAD OF THE COLD FRONT..AS IT SHIFTS
SEWD ACRS THE AIRSPACE. CVRG SHOULD BE GREATEST OVER THE CNTRL AND
ERN PRTNS OF THE AIRSPACE WITH SOME STG TO LCLY SVR STORMS
POSSIBLE. PREVAILING CONDS WILL VFR WITH BRIEF MVFR-IFR VIS
REDUCTIONS IN TSRA IMPACTS. WND SHIFT FROM SW TO NW BY TONIGHT
WITH MAIN PCPN ACTIVITY BCMG CONFINED TO SERN AREAS INTO THU.
POST-FRONTAL MVFR SEEMS PROBABLE OVER WRN SXNS TNGT.
OUTLOOK...
THU...SCT TSTM IMPACTS PSBL SERN AIRFIELDS AS COLD FRONT SLOWS
ALONG THE MID-ATLC COAST.
FRI...PATCHY MORNING FOG...OTHERWISE VFR/NO SIG WX.
SAT...PATCHY MORNING FOG...OTHERWISE VFR. ISOLD PM TSTM PSBL.
SUN...TSTM IMPACTS LKLY AS WARM FRONT LIFTS NWD ACRS AIRSPACE.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...LAMBERT
NEAR TERM...LAMBERT
SHORT TERM...LAMBERT
LONG TERM...LAMBERT/CERU
AVIATION...STEINBUGL
AREA FORECAST DISCUSSION
NWS GREENVILLE-SPARTANBURG SC
323 AM EDT WED JUL 23 2014
.SYNOPSIS...
WEAK HIGH PRESSURE ACROSS THE AREA TODAY WILL MOVE AWAY TONIGHT. A
SURFACE FRONT WILL APPROACH FROM THE NORTHWEST TONIGHT AND IS
EXPECTED TO MOVE ACROSS THE CAROLINAS AND NORTH GEORGIA THURSDAY
AFTERNOON AND EVENING. HIGH PRESSURE WILL BUILD IN BEHIND THE FRONT
FOR FRIDAY AND THE WEEKEND. ANOTHER FRONT IS EXPECTED TO PASS ON
MONDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 320 AM...EARLY MORNING FOG IS EXPECTED TO DEVELOP AND EXPAND
ACROSS THE I-77 CORRDIOR AND WITHIN THE MTN VALLEYS. THE HRRR
CONDENSATION PRESSURE DEFICITS INDICATES THAT THE LOWEST VALUES
WILL EXIST ACROSS THE SOUTHEASTERN HALF OF THE CHARLOTTE METRO AREAS
AND WITHIN THE MTN VALLEYS. FOG SHOULD DISSIPATE DURING THE FIRST
TWO HOURS OF SUNLIGHT. IN ADDITION...EARLY MIXING SHOULD YIELD A
LIGHT SOUTHWEST WIND. GREATER INSOLATION AND SOUTHWEST WINDS SHOULD
RESULT IN STEADILY WARMING TEMPERATURES FROM SUNRISE TO MID
AFTERNOON. I WILL FORECAST HIGHS TO RANGE FROM THE L80S WITHIN THE
MTNS VALLEYS TO U80S TO NEAR 90 EAST OF I-85.
RECENT W/V LOOP INDICATED THAT THE MID LEVEL LOW WAS DRIFTING WEST
ACROSS THE MISSISSIPPI RIVER DELTA...AS ANOTHER TROUGH WILL DIGGING
OVER THE OHIO RIVER VALLEY. AT THE SFC...A WEAK LEE TROUGH MAY
DEVELOP ACROSS THE PIEDMONT DURING THE AFTERNOON. A COLD FRONT WILL
APPROACH FROM THE NW TODAY...REACHING THE SOUTHERN APPALACHIANS LATE
TONIGHT. CAMS INDICATE THAT SHRA AND TSRA WILL FAVOR THE MTNS AND
ADJACENT FOOTHILLS AS EARLY AS MID MORNING TODAY. COVERAGE WILL
INCREASE THROUGH THE HEAT OF THE AFTERNOON...BECOMING SCT ACROSS THE
PIEDMONT. CONVECTION SHOULD GENERALLY DISSIPATE EAST OF THE MTNS ONE
TO TWO HOURS AFTER SUNSET. HOWEVER...I WILL MAINTAIN CHC TO LIKELY
POPS ACROSS THE TN BORDER COUNTIES TO COVER THE ARRIVAL OF PRE
FRONTAL CONVECTION. LOW TEMPERATURES TONIGHT ARE FORECAST TO RANGE
FROM THE MID 60S ACROSS THE MTNS TO LOW 70S EAST.
&&
.SHORT TERM /THURSDAY THROUGH FRIDAY NIGHT/...
AS OF 230 AM EDT WEDNESDAY...THE MODEL GUIDANCE HAS COME INTO BETTER
AGREEMENT WITH THE PASSAGE OF A SURFACE FRONT MORE OR LESS DURING
PEAK HEATING ON THURSDAY. THE FRONT WILL BE DRIVEN ACROSS THE FCST
AREA BY A FAIRLY STRONG SHORT WAVE IN THE PRESENCE OF SOME UPPER
DIVERGENCE IN THE ENTRANCE REGION OF THE JET OVER THE NORTHEAST.
PLENTY OF LOW LEVEL MOISTURE WILL REMAIN AHEAD OF THE FRONT AS WELL.
THUS...WITH THE TIMING A BIT MORE IN FOCUS...FEEL IT APPROPRIATE TO
BUMP THE PRECIP PROBABILITY UP INTO THE LIKELY RANGE ACROSS THE
ENTIRE FCST AREA IN THE AFTERNOON. MIGHT BE A BIT TOO EARLY TO TALK
TOO MUCH ABOUT SEVERE WEATHER POTENTIAL...BUT THE FRONT SHOULD FOCUS
STORMS IN AN AIR MASS WITH 1500-2500 J/KG OF CAPE...SO THE DAY2
OUTLOOK SEEMS APPROPRIATE. SUSPECT WE WILL HAVE TO CONTEND WITH
SEVERAL SEVERE THUNDERSTORMS. THE FRONT WILL DROP SE DURING THE
EVENING HOURS ENDING THE PRECIP CHANCE BY THE EARLY MORNING HOURS ON
FRIDAY.
BEHIND THE FRONT...THE AIR MASS WILL NOT REALLY BE MUCH COOLER...BUT
IT SHOULD BE A BIT DRIER ON FRIDAY. HIGH PRESSURE SHOULD MOVE IN
DURING THE DAY. NOT REALLY SEEING MUCH TO SUPPORT ANY SHOWERS IN THE
AFTERNOON SO THE PRECIP CHANCES WERE LOWERED. FRIDAY NIGHT SHOULD BE
DRY AS WELL WITH SEASONAL TEMPS.
&&
.LONG TERM /SATURDAY THROUGH TUESDAY/...
AS OF 315 AM WEDNESDAY...STILL EXPECTING THE MEAN UPPER TROF OVER
THE EAST TO FILL OVER THE WEEKEND AS A SHORT WAVE RIDGE MOVES
THROUGH. THIS WILL SUPPORT WEAK HIGH PRESSURE FOR SATURDAY AND INTO
SUNDAY. THINK CONVECTION WILL BE LIMITED TO THE RIDGETOPS SATURDAY
AFTERNOON AND HAVE CUT BACK THE ALREADY MEAGER POP A BIT MORE.
EARLIER RUNS OF THE MODELS SHOWED THE POTENTIAL FOR UPSTREAM MCS
DEVELOPMENT ON SATURDAY NIGHT...AND THAT COULD STILL HAPPEN...BUT
THE MAIN FOCUS LOOKS LIKE IT WILL BE MORE LIKE THE OH VALLEY AND
CENTRAL APPALACHIANS. SO...SATURDAY NIGHT WAS KEPT DRY ACROSS THE
MOUNTAINS AS WELL. EXPECT MORE OF A RETURN TO DIURNAL THUNDERSTORMS
FOR SUNDAY. ANOTHER IN A SERIES OF FAIRLY STRONG SHORT WAVES WILL
ONCE AGAIN CARVE OUT AN UPPER TROF OVER THE EAST EARLY NEXT WEEK. IT
STILL LOOKS LIKE THIS WAVE WILL DRIVE ANOTHER COLD FRONT OVER THE
REGION ON MONDAY. UNLIKE THE EARLIER FRONT...THIS ONE SHOULD USHER
IN A NOTICEABLY DIFFERENT AIR MASS FOR NEXT TUESDAY AS A COOL
CONTINENTAL HIGH MOVES DOWN OVER THE NRN PLAINS...THEN MODIFIES AND
BUILDS IN FROM THE WEST. THAT SHOULD DROP TEMPS A CATEGORY OR MORE
BELOW NORMAL.
&&
.AVIATION /08Z WEDNESDAY THROUGH SUNDAY/...
AT KCLT...LATEST OBSERVATION INDICATE THAT THE DEWPOINT DEPRESSION
WAS AROUND ONE DEGREE. HRRR AND NAM INDICATE THAT CONDENSATION
PRESSURE DEFICITS WILL FALL ACROSS THE CLT METRO AREA TO LESS THAN 1
MB BETWEEN 9Z TO 12Z. I WILL HIGHLIGHT THE FOG POTENTIAL WITH A
TEMPO GROUP FOR MVFR FOG BETWEEN 9Z TO 12Z. SHORTLY AFTER
SUNRISE...SW WINDS SHOULD DEVELOP WITH VFR CLOUD COVER. SCT COVERAGE
OF LATE AFTERNOON TSRA ARE POSSIBLE 18Z TO 24Z.
ELSEWHERE...THE PRIMARY CONCERN FOR THE REST OF THE NIGHT WILL BE THE
DENSITY AND PLACEMENT OF FOG. KAVL WILL SEE THE GREATEST POTENTIAL
FOR VLIFR FOG AND CEILINGS. ELSEWHERE...I WILL HIGHLIGHT THE FOG
POTENTIAL WITH A TEMPO GROUP FOR MVFR FOG BETWEEN 9Z TO 12Z. SHORTLY
AFTER SUNRISE...SW WINDS SHOULD DEVELOP WITH VFR CLOUD COVER. SCT
COVERAGE OF LATE AFTERNOON TSRA ARE POSSIBLE 18Z TO 24Z
OUTLOOK... SHOWERS AND THUNDERSTORMS THURSDAY WITH THE PASSAGE OF A
COLD FRONT. SCATTERED SHOWERS AND THUNDERSTORMS MAINLY DURING THE
AFTERNOONS AND EVENINGS THROUGH THE END OF THE WEEK.
CONFIDENCE TABLE...
07-13Z 13-19Z 19-01Z 01-07Z
KCLT MED 74% HIGH 92% HIGH 100% HIGH 100%
KGSP MED 78% HIGH 89% MED 78% HIGH 100%
KAVL HIGH 86% MED 67% HIGH 100% HIGH 100%
KHKY HIGH 91% HIGH 97% HIGH 100% HIGH 100%
KGMU MED 79% HIGH 91% HIGH 100% HIGH 100%
KAND MED 74% HIGH 91% 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
&&
.GSP WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
NC...NONE.
SC...NONE.
&&
$$
SYNOPSIS...PM
NEAR TERM...NED
SHORT TERM...PM
LONG TERM...PM
AVIATION...NED
AREA FORECAST DISCUSSION
NWS GREENVILLE-SPARTANBURG SC
258 AM EDT WED JUL 23 2014
.SYNOPSIS...
EXPECT A BRIEF RETURN TO MORE TYPICAL SUMMER WEATHER ON WEDNESDAY
BEFORE A FRONT APPROACHES AND MOVES ACROSS THE REGION ON THURSDAY.
THE PASSAGE OF THE FRONT WILL NOT BRING COOLER AIR...BUT IT SHOULD
BRING DRIER AIR FOR FRIDAY AND INTO THE WEEKEND.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
AS OF 250 AM...I WILL UPDATE THE FORECAST TO INCREASE THE FOG
MENTION WITHIN THE MTN VALLEYS AND I-77 CORRDIOR...BASED ON HRRR AND
NAM CONDENSATION PRESSURE DEFICITS.
AS OF 1020 PM...ONLY A FEW SHRA REMAIN ACROSS VARIED PARTS OF THE
CWFA THIS EVENING. ISOLATED SHRA MAY CONTINUE UNTIL SHORTLY AFTER
MIDNIGHT BUT SHUD END SHORTLY THEREAFTER. CURRENTLY MUCH LESS
CLOUDINESS THAN THE MDLS WERE SUGGESTING. HAVE BACKED OFF ON CLOUDS
THIS EVENING...BUT ALLOW SOME CLOUDS TO DEVELOP AFTER MIDNIGHT. LOWS
LOOK ON TRACK.
AS OF 740 PM...CONVECTIVE COVERAGE BEGINNING TO WANE WITH THE LOSS
OF HEATING. COVERAGE WILL CONTINUE TO DIMINISH THRU THE EVENING WITH
MOST CELLS GONE BY MIDNIGHT. HAVE UPDATED POP FOR THESE TRENDS. HAVE
BACKED OFF ON CLOUDS EARLY AS WELL GIVEN SAT PIX...BUT STILL EXPECT
LOW CLOUDS TO RETURN OVERNIGHT. OTHERWISE...GOING FORECAST ON TRACK
WITH UPDATES MAINLY FOR CURRENT CONDITIONS.
AS OF 420 PM...CONVECTION DEVELOPING ALONG AND SOUTH OF THE I-85
CORRIDOR AND SLOWLY MOVING NE. EXPECT THESE TRENDS TO CONTINUE INTO
THE EVENING WITH GREATEST COVERAGE OUTSIDE OF THE MTNS EARLY...THEN
ACROSS THE MTNS NEAR SUNSET. CONVECTION SHUD THEN SLOWLY TAPER OFF
WITH ONLY ISOLATED COVERAGE EXPECTED AFTER MIDNIGHT. HAVE UPDATED
POP...MAINLY EARLY...FOR THESE TRENDS. REST OF THE FCST LOOKS TO BE
IN GOOD SHAPE WITH ONLY UPDATES FOR CURRENT CONDITIONS NEEDED.
AT 230 PM EDT TUESDAY... FOR THE REMAINDER OF THE AFTERNOON AND
EVENING... SCATTERED SHOWERS AND ISOLATED THUNDERSTORMS WILL PERSIST
IN A MOIST BUT ONLY MODESTLY UNSTABLE AIR MASS. NO SIGNIFICANT
SURFACE FEATURES EXIST IN THE CWA TO PROVIDE AN OBVIOUS FOCUS FOR
CONVECTIVE DEVELOPMENT. EXPECT SHOWERS TO DRIFT SLOWLY TO THE
NORTHWEST WITH PERHAPS A SLIGHT PREFERENCE FOR ENHANCEMENT AND BEST
COVERAGE THIS EVENING IN AREAS WITH UPSLOPE FLOW. WINDS ALOFT
THROUGH THE EVENING WILL REMAIN QUITE LIGHT IN THE COL REGION OF THE
MID AND UPPER TROPOSPHERIC HEIGHT FIELD... SO SLOW MOVEMENT OF
CONVECTIVE CELLS IS LIKELY. OVERNIGHT FOG IS POSSIBLE... BUT MODELS
AT THIS TIME ARE NOT DEFINITIVE IN INDICATING WIDESPREAD LOW
VISIBILITY CONDITIONS. NONETHELESS... THE POTENTIAL BEARS WATCHING
OVERNIGHT. THE PRIME AREA FOR SIGNIFICANT FOG WILL BE IN THE
MOUNTAIN VALLEYS AND ACROSS THE NORTHERN FOOTHILLS INTO THE
NORTHWEST PIEDMONT OF NC.
UPPER LEVEL PATTERN ACROSS THE AREA WILL UNDERGO A TRANSITION
TONIGHT AND WEDNESDAY. THE CUTOFF LOW OVER GULF COAST STATES WILL
CONTINUE A SLOW DRIFT TO THE WEST AND HEIGHTS WILL FALL TO OUR NORTH
IN ADVANCE OF SIGNIFICANT TROUGH DIGGING INTO THE EAST. AS TROUGH
HEADS ACROSS THE GREAT LAKES TOWARD THE ATLANTIC COAST... THE
SURFACE RIDGE THAT HAS EXTENDED FROM THE MID-ATLANTIC INTO THE
CAROLINAS FOR A COUPLE OF DAYS WILL DISAPPEAR. IN ITS PLACE WE ARE
LIKELY TO HAVE A LEE TROUGH RETURN TO THE PIEDMONT PORTION OF THE
CWA BY WEDNESDAY AFTERNOON. THE FALLING HEIGHTS AND APPROACHING
DIGGING TROUGH WEDNESDAY AFTERNOON WILL BE ACCOMPANIED BY A WESTERLY
WIND FLOW ALOFT AND SOUTH TO SOUTHWEST WIND IN THE BOUNDARY LAYER.
THE RESULT WILL BE A RETURN TO A MORE DIURNAL PATTERN OF CONVECTION
WITH THE HIGHEST POPS OVER AND NEAR THE HIGHER TERRAIN. WITHOUT A
MAJOR CHANGE IN AIR MASS... SIGNIFICANT TEMPERATURE CHANGES WILL NOT
OCCUR. TUESDAY MORNING LOWS ARE EXPECTED TO BE NEAR 70 WITH 60S IN
THE MOUNTAIN VALLEYS. WEDNESDAY AFTERNOON TEMPERATURES WILL BE
BETWEEN 85 AND 90 EXCEPT IN THE LOWER AND MIDDLE 80S IN THE MOUNTAIN
VALLEYS.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH FRIDAY/...
AS OF 200 PM EDT TUESDAY...ALL NUMERICAL GUIDANCE IS FORECASTING A
STRONG SHORT WAVE TO MOVE THROUGH THE GREAT LAKES WED NIGHT INTO THU
WHICH WILL DRIVE A SURFACE COLD FRONT SOUTHEASTWARD INTO THE
SOUTHEAST STATES. THE NAM AND GFS HAVE SETTLED ON SIMILAR TIMING
IN REGARD TO THE FRONT WITH BOTH MODELS BRINGING IT TO JUST NW OF
THE NC MOUNTAINS BY 12Z THU...AND THEN BRINGING IT ACROSS THE
MOUNTAINS INTO THE LOWER PIEMDONT BY THURSDAY EVENING. THE FRONT IS
THEN FORECAST TO CLEAR THE AREA BY MIDNIGHT. A DRYER AND MORE STABLE
AIR MASS IS EXPECTED TO OVERSPREAD THE AREA ON FRIDAY AS HIGH
PRESSURE RIDGES SOUTHEASTWARD FROM THE OHIO VALLEY.
IN REGARD TO SENSIBLE WEATHER...SOME LINGERING SHOWERS AND STORMS
MAY BE OVER THE AREA WED EVENING...BUT THEY SHOULD DISSIPATE WITH
LOSS OF HEATING WED NIGHT. HOWEVER...WILL NEED TO RAMP POPS UPWARD
LATE THURSDAY NIGHT AS SOME PREFRONTAL SHOWERS MAY REACH THE
MOUNTAINS BY SUNRISE THURSDAY. WILL CONTINUE TO ADVERTISE LIKELY
POPS IN PORTIONS OF THE MOUNTAINS AND ALSO IN NC PIEDMONT ON THU
AFTERNOON...BUT CONVECTION SHOULD BE SCATTERED ELSEWHERE AS WINDS IN
PROFILES ARE DECIDELY DOWNSLOPE IN NATURE. THERE SHOULD BE PLENTY OF
INSTABILITY THU AFTERNOON WITH CAPES POOLING TO 1500-2000J OVER THE
PIEMDONT. HENCE...A FEW SEVERE STORMS ARE POSSIBLE. WILL FORECAST
DECREASING POPS THU NIGHT AND THEN A DRY DAY ON FRI. MAX TEMPS WILL
BE BELOW CLIMO BOTH THU AND FRI IN THE MOUNTAINS...BUT NEAR CLIMO
OUTSIDE THE MOUNTAINS ON THU AND THEN ABOUT A CATEGORY BELOW CLIMO
ON FRIDAY.
&&
.LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/...
AS OF 215 PM TUESDAY...THE MEDIUM RANGE GUIDANCE SUGGESTS THAT THE
EASTERN U.S. TROUGH WILL FLATTEN AS HEIGHTS RISE IN RESPONSE TO
ANOTHER STRONG UPPER WAVE DIGGING INTO THE NORTHERN PLAINS OVER THE
WEEKEND. THIS WAVE IS FORECAST TO SWING ACROSS THE GREAT LAKES AND
RE-ESTABLISH THE EASTERN U.S TROUGH BY MONDAY.
LOOKS LIKE WE SHOULD BE ABLE TO SQUEEZE OUT ONE MORE NICE DAY ON
SATURDAY BEHIND THE THURSDAY FRONTAL PASSAGE AS HIGH PRESSURE
REMAINS WEEKLY RIDGED OVER THE AREA AND MOISTURE LEVELS REMAIN
RELATIVELY LOW. HOWEVER...IT LOOKS LIKE THE FIRST PART OF NEXT
WEEK WILL TURN STORMY. ALL THE MEDIUM RANGE MODELS HINT AT A
POSSIBLE MCS MAKING A RUN AT THE SOUTHERN APPALACHIANS ON SUNDAY. IT
IS DIFFICULT TO SAY WHETHER ANY OF THE PARENT STORMS WILL MAKE IT
ACROSS THE MOUNTAINS...BUT THE OUTFLOW MAY TRIGGER ADDITIONAL STORMS
ACROSS THE PIEDMONT SUNDAY AFTERNOON AND NIGHT. ALSO..AS THE UPPER
TROUGH DIGS OVER THE GREAT LAKES EARLY NEXT WEEK A COLD FRONT IS
FORECAST TO ARRIVE ON MONDAY PROVIDING THE TRIGGER FOR MORE
THUNDERSTORMS. SEVERE STORMS ARE A POSSIBILITY FROM SUNDAY INTO
MONDAY.
THE FRONT IS FORECAST TO CLEAR THE AREA MONDAY NIGHT WHICH SHOULD
ALLOW FOR DRYER AND MORE STABLE AIR TO OVERSPREAD THE AREA FROM THE
NW ON TUESDAY. MAX TEMPS ARE FORECAST TO BE NEAR OR EVEN SLIGHTLY
ABOVE CLIMO SAT THROUGH MONDAY...AND THEN BELOW CLIMO ON TUE BEHIND
THE COLD FRONT
&&
.AVIATION /07Z WEDNESDAY THROUGH SUNDAY/...
AT KCLT...LATEST OBSERVATION INDICATE THAT THE DEWPOINT DEPRESSION
WAS AROUND ONE DEGREE. HRRR AND NAM INDICATE THAT CONDENSATION
PRESSURE DEFICITS WILL FALL ACROSS THE CLT METRO AREA TO LESS THAN 1
MB BETWEEN 9Z TO 12Z. I WILL HIGHLIGHT THE FOG POTENTIAL WITH A
TEMPO GROUP FOR MVFR FOG BETWEEN 9Z TO 12Z. SHORTLY AFTER
SUNRISE...SW WINDS SHOULD DEVELOP WITH VFR CLOUD COVER. SCT COVERAGE
OF LATE AFTERNOON TSRA ARE POSSIBLE 18Z TO 24Z.
ELSEWHERE...THE PRIMARY CONCERN FOR THE REST OF THE NIGHT WILL BE THE
DENSITY AND PLACEMENT OF FOG. KAVL WILL SEE THE GREATEST POTENTIAL
FOR VLIFR FOG AND CEILINGS. ELSEWHERE...I WILL HIGHLIGHT THE FOG
POTENTIAL WITH A TEMPO GROUP FOR MVFR FOG BETWEEN 9Z TO 12Z. SHORTLY
AFTER SUNRISE...SW WINDS SHOULD DEVELOP WITH VFR CLOUD COVER. SCT
COVERAGE OF LATE AFTERNOON TSRA ARE POSSIBLE 18Z TO 24Z
OUTLOOK... SHOWERS AND THUNDERSTORMS THURSDAY WITH THE PASSAGE OF A
COLD FRONT. SCATTERED SHOWERS AND THUNDERSTORMS MAINLY DURING THE
AFTERNOONS AND EVENINGS THROUGH THE END OF THE WEEK.
CONFIDENCE TABLE...
07-13Z 13-19Z 19-01Z 01-07Z
KCLT MED 74% HIGH 92% HIGH 100% HIGH 100%
KGSP MED 78% HIGH 89% MED 78% HIGH 100%
KAVL HIGH 86% MED 67% HIGH 100% HIGH 100%
KHKY HIGH 91% HIGH 97% HIGH 100% HIGH 100%
KGMU MED 79% HIGH 91% HIGH 100% HIGH 100%
KAND MED 74% HIGH 91% 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
&&
.GSP WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
NC...NONE.
SC...NONE.
&&
$$
SYNOPSIS...CSH
NEAR TERM...NED
SHORT TERM...LG
LONG TERM...LG
AVIATION...NED
AREA FORECAST DISCUSSION
NWS NASHVILLE TN
344 AM CDT WED JUL 23 2014
.DISCUSSION...
UPPER LOW IS LOCATED NEAR NEW ORLEANS THIS MORNING WITH AN
INVERTED TROUGH AXIS EXTENDING NORTHEASTWARD ACROSS EASTERN TN.
MEANWHILE...SFC BOUNDARY EXTENDS FROM LAKE ERIE SW THROUGH MO.
NORTHWESTERLY FLOW ALOFT TO BECOME MORE ENHANCED AS WE MOVE
THROUGH TODAY. THIS WILL ALLOW THIS FRONTAL BOUNDARY TO MOVE OUR
WAY AND MOVE ACROSS THE AREA TONIGHT. 18Z AND 00Z DEPICTIONS OF
THE UPPER LEVEL FLOW REVEAL A DIVERGING FLOW ALOFT AND THIS WILL
COUPLE WITH ELEVATED LEVELS OF CURVATURE AND SHEAR JUST TO THE
NORTHWEST OF THE DIVERGING FLOW. LATEST HRRR IN SUPPORT OF LATE
MORNING TO EARLY AFTERNOON CONVECTIVE DEVELOPMENT ACROSS OUR
SOUTHEAST WHICH IS IN CLOSER PROXIMITY TO THE INVERTED TROUGH.
THEN...BY MID AND LATE AFTERNOON...THE APPROACHING FRONTAL
BOUNDARY WILL KICK OFF SOME CONVECTION ACROSS THE NORTHWEST HALF
OF MIDDLE TN. ALL IN ALL...POPS OF 30-50 PERCENT LOOKS REASONABLE
FOR TODAY. CAPES WILL REACH 2000 J/KG BY LATE AFTERNOON SO CANNOT
RULE OUT SOME STRONG STORMS THIS AFTERNOON AND EVENING AS WELL.
SO...AGAIN TONIGHT...A GOOD CHANCE OF SHOWERS AND TSTMS WILL BE IN
THE FORECAST AS THE FROPA OCCURS AND PVA WORKS ACROSS OUR AREA.
THE FRONTAL BOUNDARY WILL BE A SLOW MOVER. THUS...LOW POPS WILL BE
INCLUDED FOR THURSDAY AS WELL.
FOR THE NEAR TERM TEMPS...ANOTHER WARM TO HOT DAY TODAY AS THE FRONT
PRESSES DOWN SLOWLY FROM THE NORTH. NOT NEARLY AS HOT ON THURSDAY AS
THE REPLACING AIRMASS FEATURES A REASONABLY IMPRESSIVE THERMAL
TROUGH FOR THIS TIME OF YEAR. THURSDAY LOOKS LIKE HIGHS IN THE
LOWER TO MID 80S WITH DEWPOINTS IN THE LOWER 60S. LOWER 60S FOR
LOWS ARE EXPECTED THU NT.
IN THE EXT FCST...UPPER TROUGHING WILL PULL EAST AS RIDGING ATTEMPTS
TO EXPAND EASTWARD FROM THE SOUTHWESTERN U.S.. NORTHWEST FLOW WILL
BE WEAKER BUT JUST STRONG ENOUGH TO ALLOW ANOTHER COLD FRONT TO MOVE
OUR WAY THIS WEEKEND. AS THE FRONT REACHES THE MID STATE ON SUNDAY
NIGHT...UPPER TROUGHING OVER THE EASTERN U.S. IS EXPECTED TO
AMPLIFY. LOOKS LIKE WE COULD SEE SOME APPRECIABLE RAINFALL FOR
SUNDAY AND SUNDAY NIGHT. INSTABILITY PARAMETERS ON SUNDAY AFTERNOON
ARE RATHER IMPRESSIVE SO ANOTHER ROUND OF STRONG STORMS LOOKS
POSSIBLE.
A FAIRLY POTENT SFC HIGH FOR LATE JULY WILL THEN BUILD IN FROM THE
NORTH. THERMAL TROUGHING LOOKS IMPRESSIVE WITH 850 MB TEMPS OF
AROUND 12C. HIGH TEMPS IN THE LOWER TO MID 80S WITH LOW RELATIVE
HUMIDITY IS EXPECTED MON THROUGH WED OF NEXT WEEK. WILL BE
UNDERCUTTING THE MEX NUMBERS AS THE EURO SOLUTION IS EVEN STRONGER
WITH THE THERMAL TROUGHING.
&&
.PRELIMINARY POINT TEMPS/POPS...
NASHVILLE 92 70 83 62 / 50 60 30 0
CLARKSVILLE 92 66 82 58 / 50 50 20 0
CROSSVILLE 85 67 81 58 / 50 60 50 10
COLUMBIA 92 70 84 63 / 40 60 30 05
LAWRENCEBURG 91 69 84 63 / 40 60 30 10
WAVERLY 92 67 82 59 / 50 50 20 0
&&
.OHX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
21
AREA FORECAST DISCUSSION
NWS MEMPHIS TN
1235 AM CDT WED JUL 23 2014
.UPDATE...AVIATION DISCUSSION.
&&
.PREV DISCUSSION... /ISSUED 1059 PM CDT TUE JUL 22 2014/
UPDATE...
SATELLITE AND RADAR HAVE SHOWN SOME REDEVELOPMENT OF SHOWERS AND
THUNDERSTORMS OVER NORTHWEST AL THAT ARE MOVING GENERALLY
WESTWARD. OTHER SHOWERS AND THUNDERSTORMS CONTINUE TO CLIP
TALLAHATCHIE AND YALOBUSHA COUNTIES IN NORTH MS. BASED ON THE 00Z
NAM AND LATEST HRRR...UPDATED TO INCLUDE AT LEAST A 20 PERCENT
CHANCE OF SHOWERS AND THUNDERSTORMS THE REMAINDER OF THE NIGHT
ACROSS MOST OF NORTH MS.
JCL
UPDATE... /ISSUED 948 PM CDT TUE JUL 22 2014/
AN UPPER LEVEL LOW PRESSURE SYSTEM WAS LOCATED ALONG THE SOUTH AL
AND SOUTH MS BORDER THIS EVENING MOVING SLOWLY WESTWARD. SCATTERED
SHOWERS AND THUNDERSTORMS ASSOCIATED WITH THIS SYSTEM THAT SPREAD
INTO PORTIONS OF NORTH MS AND WEST TN EARLIER TODAY HAVE JUST
ABOUT DISSIPATED OR MOVED OUT OF THE REGION FOR THE NIGHT. LINGERING
SHOWERS AND THUNDERSTORMS ROTATING AROUND THIS LOW PRESSURE SYSTEM
WERE MOVING SOUTHWESTWARD OUT OF YALOBUSHA COUNTY IN NORTH MS AND
MAY CLIP THE SOUTHERN PORTIONS OF TALLAHATCHIE COUNTY. OTHERWISE
RAIN FREE WEATHER IS EXPECTED ACROSS MOST OF THE REGION THE
REMAINDER OF THE NIGHT. THE LATEST NAM AND HRRR MODELS CONTINUE TO
INDICATE THE POSSIBILITY OF A FEW SHOWERS AND THUNDERSTORMS MOVING
INTO PORTIONS OF NORTHEAST AR AND THE MO BOOTHEEL LATE TONIGHT
AHEAD OF A WEAK UPPER LEVEL SHORT WAVE EMBEDDED IN NORTHWEST FLOW
ALOFT...THIS IS ALREADY INDICATED IN THE EARLIER FORECAST.
SURFACE DEW POINTS HAVE REALLY INCREASED FROM RECENT DAYS AND ARE
PRESENTLY MAINLY IN THE LOWER AND MIDDLE 70S ACROSS MOST OF THE
AREA. THIS WILL MAKE FOR A WARMER NIGHT. ADDED PATCHY FOG WITH
DECREASING TEMPERATURE AND DEW POINT DEPRESSIONS ALONG WITH LIGHT
WINDS.
UPDATED GRIDS AND GRIDS WILL BE SENT SOON.
JCL
PREV DISCUSSION... /ISSUED 345 PM CDT TUE JUL 22 2014/
CURRENTLY...A WEAK UPPER LOW LOCATED ALONG THE NORTHERN GULF
COAST IS RETROGRADING SLOWLY. MEANWHILE TO THE NORTH AN UPPER
RIDGE EXTENDS INTO THE MID MISSISSIPPI VALLEY. DEEPER MOISTURE
ASSOCIATED WITH THE UPPER LOW HAS MOVED INTO NORTH MISSISSIPPI AND
INTO AREAS NEAR THE TENNESSEE RIVER WHERE THE AIRMASS IS FAIRLY
UNSTABLE WITH SBCAPES AROUND 2500 J/KG. AS A RESULT ISOLD SHOWERS
AND THUNDERSTORMS HAVE DEVELOPED IN THOSE AFOREMENTIONED AREAS.
ELSW SKIES ARE PARTLY TO MOSTLY SUNNY. TEMPS RANGE FROM THE MID
80S AND NE MS TO AROUND 90 ELSW.
TONIGHT...THE UPPER LOW WILL CONTINUE TO RETROGRADE AND WEAKEN
OVERNIGHT. ISOLD SHOWERS AND THUNDERSTORMS ACROSS NE MISSISSIPPI AND
ALONG THE TN RIVER WILL DISSIPATE WITH LOSS OF HEATING EARLY THIS
EVENING. OTRW EXPECT A QUIET AND MILD NIGHT WITH TEMPS A FEW
DEGREES WARMER THAN LAST NIGHT SINCE SURFACE DEWPOINTS HAVE
INCREASED A BIT IN THE LAST 24 HOURS. LATER TONIGHT A COLD FRONT
WILL START TO MOVE INTO THE MIDDLE MISSISSIPPI VALLEY WHICH WILL
TRIGGER SHOWERS AND THUNDERSTORMS ACROSS MISSOURI. SOME OF THESE
COULD SNEAK INTO NE ARKANSAS BY MORNING SO ADDED A SMALL POP
THERE.
WEDNESDAY AND WEDNESDAY NIGHT...THE UPPER RIDGE BRIEFLY SNEAKS IN
AHEAD OF APPROACHING COLD FRONT ALLOWING FOR A WARM AND MUGGY DAY
FOR THE MIDSOUTH. MEANWHILE THE WEAK UPPER LOW ALONG THE NORTHERN
GULF COAST WILL PERSIST AND MAY HELP TRIGGER A FEW SHOWERS AND
THUNDERSTORMS ACROSS NORTH MISSISSIPPI. MORE IMPORTANTLY BY
AFTERNOON A COLD FRONT WILL BE APPROACHING NORTHERN AREAS OF THE
MIDSOUTH WITH CHANCES FOR SHOWERS AND THUNDERSTORMS. THE FRONT
WILL CONTINUE TO PUSH SOUTH THROUGH THE AREA WEDNESDAY NIGHT WITH
CHANCES FOR SHOWERS AND THUNDERSTORMS CONTINUING. THE AIRMASS WILL
BE QUITE UNSTABLE AHEAD OF THE FRONT AND SCATTERED SHOWERS AND
THUNDERSTORMS ARE EXPECTED WITH THE BEST CHANCES ACROSS THE
NORTHERN TIER. A FEW STRONG TO SEVERE STORMS ARE POSSIBLE WITH
DAMAGING WINDS THE MAIN THREAT WEDNESDAY AFTERNOON INTO WEDNESDAY
NIGHT. BY LATE WEDNESDAY NIGHT THE FRONT WILL BE LOCATED ACROSS
NORTHERN MISSISSIPPI AND COOLER/DRIER AIR WILL FILTER INTO
NORTHERN AREAS WITH TEMPS DROPPING INTO THE 60S.
THURSDAY THROUGH SATURDAY...THE COLD FRONT WILL EXIT NORTH
MISSISSIPPI IN THE MORNING AND HIGH PRESSURE WILL BUILD IN WITH A
LESS HUMID AIRMASS AND COOLER TEMPS. BELOW NORMAL TEMPS ARE
EXPECTED WITH HIGHS ON THURSDAY IN THE 80S AND LOWS THURSDAY NIGHT
IN THE 60S. TEMPS WILL CLIMB FRIDAY AND SATURDAY AS UPPER RIDGING
BUILDS IN. HIGHS WILL APPROACH 90 ON FRIDAY AND LOWER 90S ON
SATURDAY. CUT MEX TEMPS A FEW DEGREES SINCE IT HAS BEEN TOO WARM
ALL SUMMER.
SATURDAY NIGHT THROUGH SUNDAY NIGHT...UPPER RIDGE STARTS TO
WEAKEN SATURDAY NIGHT AND WEAK NORTHWEST FLOW DEVELOPS WITH A
BOUNDARY LOCATED TO THE NORTH OF THE AREA. THIS COULD BE AN MCS
SCENARIO. BY SUNDAY AND SUNDAY NIGHT THE EASTERN U.S. TROF
STRENGTHENS ONCE AGAIN AS MORE ENERGY DIPS SOUTH FROM CANADA. THIS
DRIVES A COLD FRONT SOUTH THROUGH THE AREA SUNDAY AND SUNDAY
NIGHT. EXPECT CHANCES FOR SHOWERS AND THUNDERSTORMS FOLLOWED BY
COOLER AND DRIER WEATHER BY EARLY NEXT WEEK. TEMPS LOOKS TO BE
WELL BELOW NORMAL MONDAY INTO MUCH OF NEXT WEEK.
SJM
&&
.AVIATION...06Z TAF CYCLE
MAINLY VFR CONDITIONS WILL CONTINUE FOR MUCH OF THE FORECAST
PERIOD. SOME AREAS OF FOG ARE EXPECTED TO DEVELOP OVERNIGHT WHICH
MAY REDUCE VISIBILITIES TO MVFR OR EVEN IFR LEVELS. A FEW
THUNDERSTORMS ARE EXPECTED TO MOVE ACROSS THE FORECAST AREA
WEDNESDAY AFTERNOON AND EVENING BUT COVERAGE APPEARS TO BE LIMITED
SO HAVE NOT MENTIONED IN TAFS AT THIS TIME. WINDS WILL BE LIGHT
AND MAINLY FROM THE SOUTHWEST FOR MUCH OF THE FORECAST PERIOD BUT
WILL START TO SHIFT TO THE NORTHWEST WEDNESDAY EVENING. &&
&&
.MEG WATCHES/WARNINGS/ADVISORIES...
AR...NONE.
MO...NONE.
MS...NONE.
TN...NONE.
&&
$$
AREA FORECAST DISCUSSION...UPDATED
NWS MEMPHIS TN
1059 PM CDT TUE JUL 22 2014
.UPDATE...
SATELLITE AND RADAR HAVE SHOWN SOME REDEVELOPMENT OF SHOWERS AND
THUNDERSTORMS OVER NORTHWEST AL THAT ARE MOVING GENERALLY
WESTWARD. OTHER SHOWERS AND THUNDERSTORMS CONTINUE TO CLIP
TALLAHATCHIE AND YALOBUSHA COUNTIES IN NORTH MS. BASED ON THE 00Z
NAM AND LATEST HRRR...UPDATED TO INCLUDE AT LEAST A 20 PERCENT
CHANCE OF SHOWERS AND THUNDERSTORMS THE REMAINDER OF THE NIGHT
ACROSS MOST OF NORTH MS.
JCL
UPDATE... /ISSUED 948 PM CDT TUE JUL 22 2014/
AN UPPER LEVEL LOW PRESSURE SYSTEM WAS LOCATED ALONG THE SOUTH AL
AND SOUTH MS BORDER THIS EVENING MOVING SLOWLY WESTWARD. SCATTERED
SHOWERS AND THUNDERSTORMS ASSOCIATED WITH THIS SYSTEM THAT SPREAD
INTO PORTIONS OF NORTH MS AND WEST TN EARLIER TODAY HAVE JUST
ABOUT DISSIPATED OR MOVED OUT OF THE REGION FOR THE NIGHT. LINGERING
SHOWERS AND THUNDERSTORMS ROTATING AROUND THIS LOW PRESSURE SYSTEM
WERE MOVING SOUTHWESTWARD OUT OF YALOBUSHA COUNTY IN NORTH MS AND
MAY CLIP THE SOUTHERN PORTIONS OF TALLAHATCHIE COUNTY. OTHERWISE
RAIN FREE WEATHER IS EXPECTED ACROSS MOST OF THE REGION THE
REMAINDER OF THE NIGHT. THE LATEST NAM AND HRRR MODELS CONTINUE TO
INDICATE THE POSSIBILITY OF A FEW SHOWERS AND THUNDERSTORMS MOVING
INTO PORTIONS OF NORTHEAST AR AND THE MO BOOTHEEL LATE TONIGHT
AHEAD OF A WEAK UPPER LEVEL SHORT WAVE EMBEDDED IN NORTHWEST FLOW
ALOFT...THIS IS ALREADY INDICATED IN THE EARLIER FORECAST.
SURFACE DEW POINTS HAVE REALLY INCREASED FROM RECENT DAYS AND ARE
PRESENTLY MAINLY IN THE LOWER AND MIDDLE 70S ACROSS MOST OF THE
AREA. THIS WILL MAKE FOR A WARMER NIGHT. ADDED PATCHY FOG WITH
DECREASING TEMPERATURE AND DEW POINT DEPRESSIONS ALONG WITH LIGHT
WINDS.
UPDATED GRIDS AND GRIDS WILL BE SENT SOON.
JCL
&&
.PREV DISCUSSION... /ISSUED 345 PM CDT TUE JUL 22 2014/
CURRENTLY...A WEAK UPPER LOW LOCATED ALONG THE NORTHERN GULF
COAST IS RETROGRADING SLOWLY. MEANWHILE TO THE NORTH AN UPPER
RIDGE EXTENDS INTO THE MID MISSISSIPPI VALLEY. DEEPER MOISTURE
ASSOCIATED WITH THE UPPER LOW HAS MOVED INTO NORTH MISSISSIPPI AND
INTO AREAS NEAR THE TENNESSEE RIVER WHERE THE AIRMASS IS FAIRLY
UNSTABLE WITH SBCAPES AROUND 2500 J/KG. AS A RESULT ISOLD SHOWERS
AND THUNDERSTORMS HAVE DEVELOPED IN THOSE AFOREMENTIONED AREAS.
ELSW SKIES ARE PARTLY TO MOSTLY SUNNY. TEMPS RANGE FROM THE MID
80S AND NE MS TO AROUND 90 ELSW.
TONIGHT...THE UPPER LOW WILL CONTINUE TO RETROGRADE AND WEAKEN
OVERNIGHT. ISOLD SHOWERS AND THUNDERSTORMS ACROSS NE MISSISSIPPI AND
ALONG THE TN RIVER WILL DISSIPATE WITH LOSS OF HEATING EARLY THIS
EVENING. OTRW EXPECT A QUIET AND MILD NIGHT WITH TEMPS A FEW
DEGREES WARMER THAN LAST NIGHT SINCE SURFACE DEWPOINTS HAVE
INCREASED A BIT IN THE LAST 24 HOURS. LATER TONIGHT A COLD FRONT
WILL START TO MOVE INTO THE MIDDLE MISSISSIPPI VALLEY WHICH WILL
TRIGGER SHOWERS AND THUNDERSTORMS ACROSS MISSOURI. SOME OF THESE
COULD SNEAK INTO NE ARKANSAS BY MORNING SO ADDED A SMALL POP
THERE.
WEDNESDAY AND WEDNESDAY NIGHT...THE UPPER RIDGE BRIEFLY SNEAKS IN
AHEAD OF APPROACHING COLD FRONT ALLOWING FOR A WARM AND MUGGY DAY
FOR THE MIDSOUTH. MEANWHILE THE WEAK UPPER LOW ALONG THE NORTHERN
GULF COAST WILL PERSIST AND MAY HELP TRIGGER A FEW SHOWERS AND
THUNDERSTORMS ACROSS NORTH MISSISSIPPI. MORE IMPORTANTLY BY
AFTERNOON A COLD FRONT WILL BE APPROACHING NORTHERN AREAS OF THE
MIDSOUTH WITH CHANCES FOR SHOWERS AND THUNDERSTORMS. THE FRONT
WILL CONTINUE TO PUSH SOUTH THROUGH THE AREA WEDNESDAY NIGHT WITH
CHANCES FOR SHOWERS AND THUNDERSTORMS CONTINUING. THE AIRMASS WILL
BE QUITE UNSTABLE AHEAD OF THE FRONT AND SCATTERED SHOWERS AND
THUNDERSTORMS ARE EXPECTED WITH THE BEST CHANCES ACROSS THE
NORTHERN TIER. A FEW STRONG TO SEVERE STORMS ARE POSSIBLE WITH
DAMAGING WINDS THE MAIN THREAT WEDNESDAY AFTERNOON INTO WEDNESDAY
NIGHT. BY LATE WEDNESDAY NIGHT THE FRONT WILL BE LOCATED ACROSS
NORTHERN MISSISSIPPI AND COOLER/DRIER AIR WILL FILTER INTO
NORTHERN AREAS WITH TEMPS DROPPING INTO THE 60S.
THURSDAY THROUGH SATURDAY...THE COLD FRONT WILL EXIT NORTH
MISSISSIPPI IN THE MORNING AND HIGH PRESSURE WILL BUILD IN WITH A
LESS HUMID AIRMASS AND COOLER TEMPS. BELOW NORMAL TEMPS ARE
EXPECTED WITH HIGHS ON THURSDAY IN THE 80S AND LOWS THURSDAY NIGHT
IN THE 60S. TEMPS WILL CLIMB FRIDAY AND SATURDAY AS UPPER RIDGING
BUILDS IN. HIGHS WILL APPROACH 90 ON FRIDAY AND LOWER 90S ON
SATURDAY. CUT MEX TEMPS A FEW DEGREES SINCE IT HAS BEEN TOO WARM
ALL SUMMER.
SATURDAY NIGHT THROUGH SUNDAY NIGHT...UPPER RIDGE STARTS TO
WEAKEN SATURDAY NIGHT AND WEAK NORTHWEST FLOW DEVELOPS WITH A
BOUNDARY LOCATED TO THE NORTH OF THE AREA. THIS COULD BE AN MCS
SCENARIO. BY SUNDAY AND SUNDAY NIGHT THE EASTERN U.S. TROF
STRENGTHENS ONCE AGAIN AS MORE ENERGY DIPS SOUTH FROM CANADA. THIS
DRIVES A COLD FRONT SOUTH THROUGH THE AREA SUNDAY AND SUNDAY
NIGHT. EXPECT CHANCES FOR SHOWERS AND THUNDERSTORMS FOLLOWED BY
COOLER AND DRIER WEATHER BY EARLY NEXT WEEK. TEMPS LOOKS TO BE
WELL BELOW NORMAL MONDAY INTO MUCH OF NEXT WEEK.
SJM
&&
.AVIATION...
00Z TAF CYCLE
MAINLY VFR CONDITIONS WILL CONTINUE FOR MUCH OF THE FORECAST
PERIOD. SOME AREAS OF FOG ARE EXPECTED TO DEVELOP OVERNIGHT WHICH
MAY REDUCE VISIBILITIES TO MVFR OR EVEN IFR LEVELS. WINDS WILL BE
LIGHT AND MAINLY FROM THE SOUTHWEST FOR MUCH OF THE FORECAST
PERIOD.
ARS
&&
.MEG WATCHES/WARNINGS/ADVISORIES...
AR...NONE.
MO...NONE.
MS...NONE.
TN...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS SAN ANGELO TX
1152 PM CDT TUE JUL 22 2014
.AVIATION...
/06Z TAFS/
VFR conditions to prevail across West Central Texas terminals
through the period. A veil of high clouds will spread across the
area from storms across Mexico, but should not effect aviation
concerns. Light east and southeast winds should continue.
&&
.PREV DISCUSSION... /ISSUED 615 PM CDT Tue Jul 22 2014/
AVIATION...
/00Z TAFS/
A few very high based, very isolated, showers and thunderstorms
developing across West Central Texas. Radar trends suggest that the
Junction and Sonora sites, KJCT and KSOA, would be the only 2 that
might be affected by one of the storms, and even that would be highly
unlikely. Thus, will not mention in the terminal forecast at this
time. Will monitor and update as needed. Otherwise, VFR conditions
and east to southeast winds should continue.
PREV DISCUSSION... /ISSUED 330 PM CDT TUE JUL 22 2014/
SHORT TERM...
(Tonight and Wednesday)
A strong subtropical ridge remains anchored over the southern
Rockies this afternoon with 500 mb heights approaching 600 dam at
the center of the anticyclone. Isolated thunderstorms have developed
over portions of West TX, basically between Lubbock and San Angelo,
moving southwest toward the Permian Basin. A few cells have
developed within the CWA from near Sweetwater to Sterling City.
Surface temperatures approaching 100 degrees have effectively
removed the cap, tapping into sufficient instability to support
thunderstorms. SPC mesoanalysis from the RAP indicates MLCAPE values
on the order of 1500 J/kg. With weak winds aloft, ordinary cells
will be the convective mode with a classic microburst profile in
place per point soundings. Isolated thunderstorms were carried
through 10 PM generally west of a line from Sweetwater to Mertzon.
Otherwise, we`ll see light winds overnight with temperatures falling
into the low to mid 70s by sunrise. Any thunderstorms lingering into
the evening hours should quickly dissipate by sunset. Temperatures
will again warm to near 100 degrees Wednesday afternoon with light
winds from a generally easterly direction.
Johnson
LONG TERM...
(Wednesday Night through Tuesday)
An upper ridge centered over northern New Mexico and the northern
Panhandle and extending north into south-central Canada will
continue to minimize our precipitation chances while giving us above
normal temperatures through the coming weekend. A developing upper
trough over the eastern half of then nation will displace the upper
ridge to the west through the by the beginning of next week. As the
upper ridge moves west there will be some relief from the unseasonal
heat as afternoon highs drop from the upper 90s and triple digits
down to the mid and upper 90s beginning next Monday. Models are
indicating a frontal boundary moving as far south as the Red River
Valley on Monday may provide a focus for some convective activity.
At this time the best chances of rainfall would be north of the
forecast area with a slight chance of some activity moving south
into at least our northern CWA. The models are also showing a TUTT
low mowing west over deep south Texas which should keep any
associated rainfall south of our area. In any event, given the
inherent uncertainty in the models this far out, will keep the
forecast dry at this time.
15
&&
.PRELIMINARY POINT TEMPS/POPS...
Abilene 74 99 74 100 74 / 0 5 5 5 5
San Angelo 73 100 71 101 72 / 5 5 5 10 5
Junction 71 98 71 98 72 / 5 5 5 10 10
&&
.SJT WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
07
AREA FORECAST DISCUSSION
NWS CHEYENNE WY
253 AM MDT WED JUL 23 2014
.SHORT TERM...(TODAY THROUGH FRIDAY)
ISSUED AT 300 AM MDT WED JUL 23 2014
LOTS OF FORECAST CHALLENGES WITH THIS FORECAST PACKAGE...RANGING
FROM SEVERE CONVECTIVE WEATHER TODAY TO FIRE WEATHER CONCERNS
THURSDAY AND FRIDAY.
CURRENTLY...THE MUCH ANTICIPATED COLD FRONT DID MOVE INTO THE AREA
LAST EVENING AND IS CURRENTLY LOCATED GENERALLY ALONG A LINE FROM
CASPER...ALONG THE LARAMIE RANGE DOWN TO LARAMIE AND THEN INTO
NORTHEASTERN COLORADO. THIS FRONT IS SEPARATING VERY MOIST AIR
EAST OF THE FRONT...CHEYENNE HAS A 1AM DEWPOINT OF 57F/LARAMIE
55F...FROM VERY DRY AIR OUT OVER CARBON COUNTY WHERE THE DEWPOINT
AT RAWLINS IS 29F. THIS FEATURE IS GOING TO PLAY A MAJOR ROLE IN
TODAYS FORECAST WEATHER.
FOR TODAY...FRONT IS GOING TO REMAIN AT ITS CURRENT LOCATION
THROUGH THE MORNING HOURS BEFORE IT STARTS TO GET FORCED EAST WITH
INCREASING WESTERLY FLOW. LATEST HRRR FORECAST COMPOSITE
REFLECTIVITY HAS CONVECTION INITIATING ACROSS ALBANY COUNTY AND
THE SOUTH LARAMIE RANGE RIGHT AROUND 20Z TODAY DURING PEAK
HEATING. NAM SOUNDING FOR CHEYENNE HAS CAPE AROUND 1300 J/KG AT
THAT TIME WITH NO CONVECTIVE INHIBITION. PANHANDLE STAYS CAPPED A
LITTLE LONGER...NOT BREAKING THE CAP UNTIL AFTER 00Z. MUCH MORE
UNSTABLE OUT THERE WITH CHADRON NAM SOUNDING SHOWING SBCAPE CLOSE
TO 3500 J/KG. THINK DAY 1 SPC SLIGHT RISK AREA IS PRETTY
GOOD...BUT DO THINK THE LARAMIE COUNTY IS GOING TO SEE SOME SEVERE
THUNDERSTORMS AS WELL AND HAVE TAILORED OUR FORECAST WITH LARAMIE
COUNTY EXPERIENCING SEVERE THUNDERSTORMS THIS AFTERNOON. SEVERE
THUNDERSTORMS INITIALLY OVER THE SOUTHEAST WYOMING PLAINS...THEN
SPREADING EAST INTO THE PANHANDLE AFTER 00Z...AS THE FRONT MOVES
EAST AS A DRY LINE.
FOR THURSDAY...UPPER LOW MOVES INTO MONTANA THURSDAY AFTERNOON
WITH 700MB WINDS INCREASING OVER WYOMING. BY 18Z GFS 700MB WINDS
INCREASE TO 25-30KTS OVER CARBON AND ALBANY COUNTIES. BOTH THE GFS
AND ECMWF SHOW A UPPER LEVEL SHORTWAVE TRACKING THROUGH THE UPPER
RIDGE ALONG THE COLORADO/WYOMING LINE THAT WILL INTERACT WITH SOME
RESIDUAL MONSOONAL MOISTURE TO CREATE AFTERNOON THUNDERSTORMS. GFS
HAS PRECIP MAINLY OVER COLORADO...WHILE ECMWF SPREAD THIS MOISTURE
NORTH INTO WYOMING. DID A BLEND OF THE TWO MODELS WITH CHANCE
SHOWERS AND THUNDERSTORMS OVER SOUTHERN WYOMING NEAR THE COLORADO
BORDER, FORECAST SOUNDING SHOW THE POSSIBILITY OF DRY
THUNDERSTORMS OUT WEST OF THE LARAMIE RANGE THAT HAS ME A LITTLE
WORRIED ABOUT FIRE STARTS AS AFTERNOON MIN HUMIDITIES FALL TO 10
PERCENT ACROSS CARBON...NORTH ALBANY AND WEST CONVERSE COUNTIES.
WENT AHEAD WITH A FIRE WEATHER WATCH FOR THURSDAY FOR CONVERSE
COUNTY AS THIS AREA LOOKS TO BE THE BEST FOR A COMBINATION OF LOW
HUMIDITIES...GUSTY WINDS AND DRY THUNDERSTORMS.
GUSTY WEST WINDS CONTINUE INTO FRIDAY WITH VERY DRY DOWNSLOPING
WINDS OFF THE LARAMIE RANGE. COULD BE LOOKING AT WIDESPREAD FIRE
WEATHER CONDITIONS FRIDAY.
.LONG TERM...(FRIDAY NIGHT THROUGH TUESDAY)
ISSUED AT 240 AM MDT WED JUL 23 2014
MODELS GENERALLY IN GOOD AGREEMENT THROUGH THE WEEKEND WITH THE
OVERALL PATTERN...SHOWING A POTENT UPPER LEVEL TROUGH DIGGING
SOUTHWARD OUT OF CANADA AND INTO THE GREAT LAKES REGION BY EARLY
SUNDAY. THIS WILL RESULT IN NORTHWEST FLOW OVER THE FORECAST AREA
AS THE STRONG UPPER LEVEL HIGH NUDGES SOUTHWARD AND THE
ASSOCIATED RIDGE AXIS WILL EXTEND NORTHWEST INTO THE GREAT BASIN
REGION. THERE ARE STILL DISCREPANCIES BETWEEN MODELS REGARDING
AVAILABLE LOW TO MIDLEVEL MOISTURE THROUGH THE WEEKEND AND INTO
EARLY NEXT WEEK. ALTHOUGH A SERIES OF COOL FRONTS ARE EXPECTED TO
PUSH SOUTHWARD ACROSS THE FORECAST AREA BEGINNING FRIDAY
NIGHT...THE LACK OF ANY DEFINED DISTURBANCES IS CREATING QUITE A
BIT OF UNCERTAINTY WITH TSTORM CHANCES INTO MONDAY. CURRENT 00Z
MODELS ARE BEGINNING TO TREND DRIER...AS THE NORTHWEST FLOW
RESULTS IN A BIT MORE STABILITY THAN PREVIOUSLY EXPECTED...NUDGING
THE MONSOON MOISTURE FURTHER SOUTH INTO THE FOUR CORNERS REGION
AND COLORADO. STARTED TO LOWER POP FOR THIS WEEKEND ACROSS MOST OF
THE AREA...ESPECIALLY FURTHER NORTH SINCE THE ECMWF IS NOW
TRENDING DRIER AS WELL. CURRENT SOUNDINGS SHOW TOO MUCH DRY AIR
ALOFT...SUPPRESSING ANY CONVECTION THAT DOES FORM. AFTER ANOTHER
WARM DAY ON SATURDAY...EXPECT TEMPERATURES TO LOWER BELOW NORMAL
ON SUNDAY WITH HIGHS IN THE 70S TO MID 80S UNDER COOL EAST TO
NORTHEAST FLOW.
CONDITIONS BECOME A LITTLE MORE INTERESTING AFTER MONDAY AS BOTH
THE GFS AND ECMWF SHOW SHORTWAVE ENERGY MOVING CLOCKWISE AROUND
THE MAIN UPPER LEVEL HIGH AND INTO WYOMING. INCREASED POP LATE MONDAY
THROUGH WEDNESDAY...MAINLY IN THE AFTERNOON AND EVENINGS. BOTH THE
GFS AND ECMWF ARE ON THE AGGRESSIVE SIDE WITH A HIGHER COVERAGE OF
SHOWERS AND TSTORMS...AT LEAST SCATTERED DURING THE AFTERNOON...AS
THE SHORTWAVE ENERGY PUSHES ACROSS EASTERN WYOMING BY WEDNESDAY.
KEPT TEMPERATURES A FEW DEGREES BELOW NORMAL DUE TO EASTERLY
UPSLOPE FLOW AND 700MB TEMPERATURES LOWERING TO BELOW 10C.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH WEDNESDAY NIGHT)
VFR CONDITIONS WILL PREVAIL THROUGH WEDNESDAY NIGHT...ALTHOUGH
BRIEF MVFR VIS ARE POSSIBLE IN AND AROUND THUNDERSTORM ACTIVITY
THIS AFTERNOON AND THIS EVENING. ANOTHER ROUND OF SHOWERS AND
THUNDERSTORMS WILL AFFECT THE HIGH PLAINS IN ADDITION TO KLAR
BEGINNING EARLY THIS AFTERNOON. THERE IS A SLIGHT CHANCE OF LOW
CIGS EARLY THIS MORNING ACROSS PARTS OF THE HIGH PLAINS...BUT
THERE IS STILL TOO MUCH UNCERTAINTY AT THIS TIME TO ADD TO AREA
TAFS.
&&
.FIRE WEATHER...
ISSUED AT 300 AM MDT WED JUL 23 2014
DRY CONDITIONS ACROSS WESTERN CARBON COUNTY AGAIN TODAY. A COLD
FRONT GENERALLY ALONG A LINE FROM CASPER TO LARAMIE WILL SEPARATE
RELATIVELY MOIST AIR EAST OF THE FRONT FROM THE REALLY DRY AIR TO
THE WEST. WETTING RAINS ARE LIKELY IN THE EASTERN SECTOR TODAY AND
TONIGHT WITH EXCELLENT OVERNIGHT RH RECOVERIES. CONDITIONS CHANGE
FOR THURSDAY THOUGH AS THE FRONT BEGINS TO MOVE EAST AGAIN AND
WINDS BEGIN TO PICK UP WEST OF THE LARAMIE RANGE. CRITICAL FIRE
WEATHER CONDITIONS FROM GUSTY WINDS AND LOW HUMIDITIES EARLY
THURSDAY AFTERNOON. TO COMPLICATE THE CONDITIONS MORE...WE HAVE
THE POSSIBILITY OF DRY THUNDERSTORMS WEST OF THE LARAMIE RANGE
THAT COULD CREATE SOME FIRE STARTS THURSDAY AFTERNOON. A FIRE
WEATHER WATCH HAS BEEN ISSUED FOR FWZ 301 FOR THURSDAY LATE
MORNING THROUGH THE AFTERNOON. DRY AND WINDY CONDITIONS TO
CONTINUE INTO SATURDAY FOR MORE WIDESPREAD FIRE WEATHER CONDITIONS
ACROSS SOUTHEAST WYOMING.
&&
.CYS WATCHES/WARNINGS/ADVISORIES...
WY...FIRE WEATHER WATCH FROM THURSDAY MORNING THROUGH THURSDAY
AFTERNOON FOR WYZ301.
NE...NONE.
&&
$$
SHORT TERM...CLAYCOMB
LONG TERM...TJT
AVIATION...TJT
FIRE WEATHER...CLAYCOMB
AREA FORECAST DISCUSSION
NWS CHEYENNE WY
1135 PM MDT TUE JUL 22 2014
.UPDATE...
ISSUED AT 835 PM MDT TUE JUL 22 2014
REGIONAL RADARS SHOWED ISOLATED STRONG CONVECTION THAT PRODUCED
LARGE HAIL NORTHWEST OF CHEYENNE EARLIER THIS EVENING HAS DISSIPATED
AS IT MOVED INTO THE SOUTHERN NEBRASKA PANHANDLE. A CLUSTER OF
STRONG TO SEVERE TSTORMS WAS MOVING SOUTHEAST ALONG A INSTABILITY
AXIS /SBCAPES 2000-3000 J/KG/ TOWARD THE NORTHERN NEBRASKA PANHANDLE.
THESE STORMS SHOULD EXIT OUR NORTHERN PANHANDLE ZONES BY MIDNIGHT.
ANOTHER ACTIVE TSTORM CLUSTER OVER SOUTHEAST MT SHOULD PASS NORTH OF
OUR NORTHERN CWA TONIGHT. UPDATED ZONES TO INCREASE POPS OVER THE
NORTHERN PANHANDLE AND REMOVE THEM OVER SOUTHEAST WY AND SOUTHERN
NEBRASKA PANHANDLE.
&&
.SHORT TERM...(THIS EVENING THROUGH THURSDAY NIGHT)
ISSUED AT 306 PM MDT TUE JUL 22 2014
FAR LESS COVERAGE OF CU COMPARED TO THE SAME TIME MONDAY WHICH
SURELY IS INDICATIVE OF THE WARMER TEMPS ALOFT. SFC MOISTURE HAS
INCREASED BEHIND LAST NIGHTS WEAK BOUNDARY...WITH THE 50F
ISODROSOTHERM BANKED UP TO THE FRONT RANGE. AM BEGINNING TO SEE SOME
WEAK CONVECTIVE DEVELOPMENT MAINLY IN THE VICINITY OF THE NRN
LARAMIE RANGE...AND SOME NR THE SNOWY AND SOUTHERN LARAMIE RANGE
TOO. MESOANALYSIS SHOWS A PRETTY HEALTHY CAPPING INVERSION REMAINS
IN PLACE...ESPECIALLY OVR THE ERN PLAINS. EXPECT THIS CAP CONTINUE
TO ERODE THRU THE AFTERNOON. THE STRONGER CAP WILL MEAN DEEP
CONVECTION WILL BE A BIT LATER IN DEVELOPING...WHICH ACCORDING TO
THE HRRR WILL BE BETWEEN 3-6 PM. LARAMIE COUNTY AND THE SOUTHERN END
OF GOSHEN/PLATTE COUNTIES LOOK TO SEE THE BEST CHANCE INITIALLY.
WILL SEE ADDITIONAL DEVELOPMENT OVR NORTHEAST WYOMING DIVE SOUTHEAST INTO
FAR EAST CENTRAL WYOMING AND THE NRN NEBRASKA PANHANDLE THIS
EVENING. IT IS THIS AREA WHERE SEVERE POTENTIAL WILL BE GREATEST
WITH SBCAPES OF AROUND 2000 J/KG ONCE THE CAP BREAKS. THIS
CONVECTION WILL DISSIPATE BY AROUND SUNSET.
ATTENTION THEN TURNS TO A BETTER CHANCE FOR SEVERE THUNDERSTORM
DEVELOPMENT WEDNESDAY AFTERNOON. THERMODYNAMIC PROFILES WILL BE MORE
CONDUCIVE FOR THUNDERSTORM DEVELOPMENT WEDNESDAY AS MID-LEVEL
HEIGHTS/TEMPS FALL WITH THE APPROACH OF SHORTWAVE ENERGY. THIS WILL
MEAN LESS OF A CAP AND A LIKELY EARLIER START TO CONVECTIVE
INITIATION...WHICH SHOULD OCCUR OVR THE SNOWY/SIERRA MADRE RANGES BY
MIDDAY. PROGGED SBCAPES OVR THE ERN PLAINS CLIMB ABOVE 3000 J/KG
WEDNESDAY AFTERNOON AND WHEN COMBINED WITH DEEP LAYER SHEAR OF 25-30
KNOTS SHOULD BE SUFFICIENT FOR SOME CONVECTIVE ACTIVITY BECOMING
SEVERE. STORMS WILL SPREAD ONTO THE SOUTHEAST WYOMING PLAINS
WEDNESDAY AFTERNOON AND INTO THE WESTERN NEBRASKA PANHANDLE DURING
THE EVENING. AREAS OVR THE SOUTHERN PANHANDLE MAY BE INFLUENCED A
BIT TOO MUCH BY THE CAP...WHICH MAY LIMIT CONVECTIVE STRENGTH THERE.
CONVECTION AGAIN WILL WANE WITH LOSS OF INSOLATION.
FIRST SHORTWAVE PUSHES THRU THURSDAY MORNING WITH A TRAILING
SHORTWAVE POISED TO MOVE THRU THURSDAY AFTERNOON. INSTABILITY AXIS
WILL BE FLATTENED AND WEAKENED BY THE INITIAL SHORTWAVE. SO EXPECT A
LESS FAVORABLE ENVIRONMENT FOR SEVERE THUNDERSTORM POTENTIAL. EVEN
SO...WEAK INSTABILITY PARAMETERS WILL BE SUFFICIENT FOR AT LEAST
SOME ISOLATED CONVECTIVE POTENTIAL. THURSDAY WILL BE THE WARMEST DAY
OF THE PERIOD WITH HIGH TEMPERATURES THAT WILL AGAIN REACH 90S AT
MOST LOCATION AND LOW TRIPLE DIGITS OVER LOWER ELEVATIONS OF THE
WESTERN NEBRASKA PANHANDLE.
.LONG TERM...(FRIDAY THROUGH MONDAY)
ISSUED AT 306 PM MDT TUE JUL 22 2014
HIGH PRESSURE CONTINUES TO REMAIN DOMINANT OVER THE FOUR CORNERS
REGION BUT BEGINS TO ERODE TO THE SOUTH OVER THE WEEKEND. FAIRLY POTENT
TROUGH OF LOW PRESSURE MOVES ACROSS THE SOUTHERN CANADIAN PROVINCES
AND BRINGS A SERIES OF ASSOCIATED COOL FRONTS ACROSS THE AREA (THE
STRONGEST FRONT WILL BE SAT EVENING). UPSLOPE FLOW LOOKS TO DEVELOP
BY FRI AFTN AS DEW POINTS APPROACH THE MID 50S OVER THE PANHANDLE.
COULD SEE SOME ISOLATED SHOWERS AND THUNDERSTORMS DURING THIS
TIME FRAME BOTH FRI AND SAT SO HAVE KEPT SOME SLIGHT POPS IN THE
FCST. THE ECMWF IS MORE MOIST THAN THE GFS ATTM AND GENERATES A
BETTER COVERAGE OF STORMS EACH AFTN AND EVENING. TEMPS BEGIN TO COOL
TO MORE SEASONABLE LEVELS IN THE LOW TO MID 80S FOR SUNDAY...BUT THE
RIDGE BEGINS TO BUILD BACK INTO THE AREA AND TEMPS SHOULD WARM TO
THE MID 80S BY MONDAY FOR SOUTHEASTERN WY AND NEAR 90 FOR AREAS OF
THE PANHANDLE AS 700 MB TEMPS WARM TO NEAR 15C.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH WEDNESDAY EVENING)
ISSUED AT 1131 PM MDT TUE JUL 22 2014
VFR CONDITIONS WILL PREVAIL THROUGH WEDNESDAY. INCREASING MOISTURE
IN THE MID LEVELS ON WEDNESDAY AFTERNOON MAY RESULT IN ANOTHER ROUND
OF SHOWERS AND THUNDERSTORMS AFFECTING THE HIGH PLAINS AND KLAR.
MVFR VIS ARE POSSIBLE IN THE AREAS OF HEAVIER RAINFALL. THERE IS A
SLIGHT CHANCE OF LOW CIGS EARLY WEDNESDAY MORNING ACROSS PARTS OF
THE HIGH PLAINS...BUT THERE IS TOO MUCH UNCERTAINTY WITH THE
LOCATION TO ADD LOW CIGS TO ANY TERMINAL AT THIS TIME.
&&
.FIRE WEATHER...
ISSUED AT 306 PM MDT TUE JUL 22 2014
WINDS HAVE HELD BELOW CRITICAL THRESHOLDS THUS FAR TODAY...DESPITE
RELATIVE HUMIDITIES THAT HAVE DROPPED BELOW 15 PERCENT. SOME
ISOLATED SHOWERS AND THUNDERSTORMS ARE EXPECTED TO DEVELOP OVER
LARAMIE COUNTY LATE THIS AFTERNOON AND OVER EXTREME EAST CENTRAL
WYOMING AND THE NORTHERN NEBRASKA PANHANDLE THIS EVENING. WEDNESDAY
WILL PROVIDE A BETTER OPPORTUNITY FOR AFTERNOON AND EVENING
THUNDERSTORMS ACROSS THE DISTRICT...SOME OF WHICH COULD POTENTIALLY
BECOME SEVERE IN LOCATIONS EAST OF THE LARAMIE RANGE. DRIER AND
BREEZIER CONDITIONS WILL EXIST OVER WESTERN CARBON AND CONVERSE
COUNTIES ON WEDNESDAY. CONDITIONS WILL LIKELY BECOME NEAR CRITICAL
IN THESE AREAS WEDNESDAY. THURSDAY LOOKS POTENTIALLY MORE CRITICAL
OVER WESTERN CARBON AND CONVERSE COUNTIES AND WILL LIKELY NEED TO
ISSUE A HEADLINE IN TIME. AFTERNOON AND EVENING SHOWER AND
THUNDERSTORM CHANCES WILL CONTINUE THURSDAY AND FRIDAY MAINLY FOR
AREAS EAST OF THE LARAMIE RANGE.
&&
.CYS WATCHES/WARNINGS/ADVISORIES...
WY...NONE.
NE...NONE.
&&
$$
UPDATE...JAMSKI
SHORT TERM...HAHN
LONG TERM...FINCH
AVIATION...HAMMER
FIRE WEATHER...HAHN
AREA FORECAST DISCUSSION
NWS MIAMI FL
947 AM EDT WED JUL 23 2014
.UPDATE...
PLAN TO MAKE SOME ADJUSTMENTS TO THE POPS OVER AT LEAST THE
INTERIOR AS THEY SEEM A BIT HIGH BASED ON CURRENT TRENDS. WATER
VAPOR IMAGERY AND THE 12Z MFL SOUNDING BOTH SHOW SIGNIFICANT
DRYING HAS OCCURRED ABOVE THE 500MB LEVEL. HOWEVER, THE LOW LEVELS
REMAIN QUITE MOIST WITH A PWAT OF JUST UNDER 2 INCHES AND WITH
DIURNAL HEATING BEGINNING IN EARNEST THIS MORNING ALREADY HAVE
CONVECTION FIRING ACROSS THE EAST COAST METRO REGION. LOOKING AT
THE CONVECTIVE PARAMETERS, THE CAPE IS OVER 2000 J/KG, 500MB
TEMPERATURE WARMED TO 4.7C AND THE MID LEVEL LAPSE RATE IS NEAR
5.5C/KG. WITH THE EXCEPTION OF THE CAPE AND THE PWAT, THESE
NUMBERS ARE VERY UNIMPRESSIVE AND BELOW THE AVERAGE FOR MID/LATE
JULY. STILL, IT SEEMS THE HIGH PWAT AND CAPE ALONG WITH STRONG
DIURNAL HEATING WILL SOMEWHAT COUNTERACT THE OTHER LOW CONVECTIVE
ELEMENTS. THE HRRR HAS BEGUN TO SHOW LESS OVERALL COVERAGE OVER
THE INTERIOR FOR THIS AFTERNOON THAN THE 70-80% ORIGINALLY
ADVERTISED, SO WITH THE LESS THAN AMPLE PARAMETERS WILL ONLY LOWER
THE POPS SLIGHTLY UNTIL LATER TRENDS DICTATE OTHERWISE.
KOB
&&
.PREV DISCUSSION... /ISSUED 740 AM EDT WED JUL 23 2014/
AVIATION...
HIGH PRESSURE IS SLOWLY BEGINNING TO BUILD OVER THE AREA FROM THE
EAST. THIS WILL KEEP A SOUTH TO SOUTHEAST FLOW OVER SOUTH FLORIDA.
THIS WILL ALSO HELP TO PUSH SHOWERS AND THUNDERSTORMS INTO THE
INTERIOR BY THE EARLY AFTERNOON. DID KEEP VCTS IN THE TAFS UNTIL
AROUND 10Z FOR THE EASTERN TAF LOCATIONS. KAPF MAY SEE A LONGER
DURATION OF IMPACT FROM CONVECTION, SO KEPT THE VCTS IN UNTIL
23Z. SO, GENERALLY VFR CONDITIONS WITH BRIEF IFR POSSIBLE DUE TO
ANY SHOWERS AND OR THUNDERSTORMS THAT MOVE OVER THE TAF SITES. THE
WIND WILL GO LIGHT AND VARIABLE ONCE AGAIN, BY LATE EVENING.
PREV DISCUSSION... /ISSUED 400 AM EDT WED JUL 23 2014/
SYNOPSIS...
SLIGHT DRIER AIR WILL MOVE INTO THE AREA THIS AFTERNOON AND
TONIGHT...AS HIGH PRESSURE BUILDS IN. THIS HIGH PRESSURE WILL
DOMINATE SOUTH FLORIDA WEATHER AT LEAST INTO EARLY NEXT WEEK.
SHORT TERM /TODAY THROUGH FRIDAY/...
HIGH PRESSURE CENTERED NORTH AND EAST OF THE BAHAMAS WILL
GRADUALLY STRENGTHEN TODAY...WITH DRIER AIR SPILLING NORTHWARD
INTO SOUTH FLORIDA THIS AFTERNOON AND TONIGHT. STILL PLENTY OF
MOISTURE FOR SEA-BREEZE TO INDUCE SCATTERED TO NUMEROUS SHOWERS
AND THUNDERSTORMS...BUT COVERAGE WILL BE LESS THAN PREVIOUS FEW
DAYS...ESPECIALLY OVER EAST COAST URBAN AREAS WHERE DRY AIR WILL
BE FIRST TO REACH. THIS DRIER THAN NORMAL AIRMASS WILL REMAIN OVER
SOUTH FLORIDA THROUGH THE SHORT TERM...AS RIDGE AXIS ORIENTS OVER
THE PENINSULA. RAIN CHANCES WILL BE LOWER THAN NORMAL BOTH
THURSDAY AND FRIDAY...AND SHOULD BE MOSTLY FOCUSED OVER THE
INTERIOR WHERE SEA-BREEZES INTERACT.
LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/...
DEEP LAYER RIDGE WILL STRENGTHEN FURTHER OVER THE WEEKEND.
SCATTERED DAYTIME SHOWERS AND THUNDERSTORMS WILL STILL BE
POSSIBLE...BUT ACTIVITY WILL BE LESS WIDESPREAD THAN TYPICAL OF
LATE JULY RAINY SEASON. EARLY NEXT WEEK...AN UPPER LEVEL TROUGH
AND ASSOCIATED COLD FRONT WILL DIG INTO THE DEEP SOUTH AND
SOUTHEAST CONUS. AFOREMENTIONED HIGH PRESSURE SHOULD KEEP THESE
FEATURES FROM HAVING MUCH IMPACT ON SOUTH FLORIDA...BUT OVERALL
WINDS BECOMING MORE SOUTHERLY/SOUTHWESTERLY...AS OPPOSED TO
SOUTHEAST...MAY ALLOW FOR CONVECTION TO SPREAD TOWARD EAST COAST
MORE. SLIGHTLY WARMER TEMPERATURES COULD ALSO RESULT.
MARINE...
HIGH PRESSURE BUILDING OVER THE WATERS WILL RESULT LIGHT
WINDS...SOUTH AT 10 KTS OR LESS...AND SEAS OF 2 FEET OR
LESS...THROUGH THE WEEKEND. THUNDERSTORMS WILL BE LESS WIDESPREAD
THAN PREVIOUS FEW DAYS...BUT SCATTERED ACTIVITY IS STILL POSSIBLE
THROUGHOUT THE PERIOD.
&&
.PRELIMINARY POINT TEMPS/POPS...
WEST PALM BEACH 90 77 90 78 / 40 10 20 10
FORT LAUDERDALE 89 80 90 81 / 30 10 30 10
MIAMI 91 79 91 78 / 40 20 30 10
NAPLES 91 76 91 77 / 40 20 30 20
&&
.MFL WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
AM...NONE.
GM...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS PEACHTREE CITY GA
1052 AM EDT WED JUL 23 2014
.UPDATE...
UPPER LOW CONTINUES ACROSS THE LA COAST THIS MORNING. AT THE
SURFACE...A WEAK BOUNDARY REMAINS ACROSS SOUTHERN GA. REGIONAL
RADAR TRENDS SHOW SOME ISOLD SHOWERS DEVELOPING ACROSS THE
NORTHERN METRO AREA. LATEST RUNS OF THE HRRR LOOK PRETTY GOOD WITH
THE HIGHEST POPS ACROSS THE NORTHERN HALF OF THE CWFA THIS
AFTERNOON...WITH COVERAGE OF STORMS REMAINING ISOLD TO SCT. 12Z
SOUNDING SHOWS HIGH PWATS AND BL WINDS BELOW 15KT...SO ANY STORMS
THAT DEVELOP WILL BE SLOW MOVERS AND CAPABLE OF PRODUCING LOCALLY
HEAVY RAINFALL.
&&
.PREV DISCUSSION... /ISSUED 727 AM EDT WED JUL 23 2014/
SHORT TERM /TODAY THROUGH THURSDAY/...
/ISSUED AT 503 AM EDT WED JUL 23 2014/
MODELS CONTINUE IN GOOD AGREEMENT THROUGH THE SHORT TERM. WIDELY
SCATTERED SHOWERS CONTINUE ACROSS MAINLY NORTH GA EARLY THIS MORNING
AND WHILE THIS WILL DIMINISH TOWARD SUNRISE...EXPECT CONVECTION TO
INCREASE AGAIN LATE THIS MORNING AND AFTERNOON. THE BEST CHANCES
WILL BE ACROSS NORTH GA. A SHORT WAVE WILL MOVE INTO THE CWA
THURSDAY ALONG WITH AN ASSOCIATED WEAK FRONT. THIS WILL BE ENOUGH TO
INCREASE CHANCES OF TSTORMS TO HIGH CHANCE TO LIKELY ACROSS THE
CWA...MAINLY DURING THE AFTERNOON ON THURSDAY. AT THIS TIME WE DO
NOT EXPECT SEVERE THUNDERSTORMS THURSDAY...HOWEVER BRIEF HEAVY RAIN
IS POSSIBLE.
17
LONG TERM /THURSDAY NIGHT THROUGH TUESDAY/...
/ISSUED AT 503 AM EDT WED JUL 23 2014/
ACTIVE PATTERN IS EXPECTED TO CONTINUE THROUGH THE EXTENDED
PERIODS WITH SEVERAL FEATURES IMPACTING THE AREA...BUT MODELS ARE
IN BETTER AGREEMENT WITH SHOWING RELATIVELY QUIET PERIODS IN
BETWEEN. HAVE ACTUALLY DECREASED POPS SLIGHTLY FRIDAY AND INTO THE
WEEKEND BEHIND THE AFOREMENTIONED FRONT. ALTHOUGH SEVERAL MODELS
PUSH THE FRONT THROUGH THE ENTIRE CWA BY SATURDAY...THERE IS STILL
SOME UNCERTAINTY REGARDING THE POSITION OF THE FRONT AND
ASSOCIATED MOISTURE ACROSS SOUTH GEORGIA. AS A RESULT...HAVE
CONTINUED MENTION OF CHANCE POPS ACROSS THE FAR SOUTH AND
SOUTHEAST CWA ON SATURDAY. MOISTURE RETURNS TO THE AREA SUNDAY AS
NEXT SHORTWAVE APPROACHES AND LONGWAVE TROUGH STARTS TO SET UP
OVER THE EASTERN UNITED STATES. CHANCE POPS SUNDAY CONTINUE INTO
EARLY WEEK AND THEN EXIT QUICKLY LATE MONDAY AS SECOND FRONT
PUSHES THROUGH. LONGWAVE TROUGH MAINTAINS ITS POSITION OVER THE
EASTERN U.S. THROUGH MID WEEK...AND WITH SURFACE HIGH ACROSS THE
AREA BEHIND THE FRONT...LOWER PRECIP CHANCES AND COOLER
TEMPERATURES ARE IN STORE.
IN GENERAL...EXPECT A SLIGHT WARMING TREND OVER THE WEEKEND...THEN
BACK TO NEAR NORMAL OR SLIGHTLY BELOW NORMAL TEMPERATURES WITH THE
SECOND FRONT EARLY NEXT WEEK.
31
AVIATION...
12Z UPDATE...
SCATTERED SHOWERS CONTINUE ACROSS PARTS OF NORTH GA. SHOWERS WILL
CONTINUE TO DEVELOP ACROSS NORTH GEORGIA THROUGH THE MORNING WITH
THUNDER DEVELOPING LATE THIS MORNING/AFTERNOON...MAINLY ACROSS NORTH
GA. THE CONVECTION WILL DIMINISH LATE THIS EVENING. VFR SKIES
CURRENTLY OVER THE TAF SITES AND EXPECT VFR CONDITIONS TO PREVAIL
THROUGH THIS EVENING. WINDS ARE CURRENTLY LIGHT AND VARIABLE...BUT
WITH MIXING THEY WILL COME AROUND TO THE WEST BUT REMAIN LIGHT IN
SPEED.
//ATL CONFIDENCE...12Z UPDATE...
MEDIUM TO HIGH ON ALL ELEMENTS.
17
&&
.PRELIMINARY POINT TEMPS/POPS...
ATHENS 90 70 89 70 / 30 30 60 40
ATLANTA 88 71 87 71 / 30 30 60 20
BLAIRSVILLE 80 66 82 64 / 40 40 60 20
CARTERSVILLE 87 69 87 68 / 40 40 60 20
COLUMBUS 91 72 90 73 / 30 20 60 30
GAINESVILLE 86 70 87 69 / 40 30 60 30
MACON 91 72 91 72 / 30 20 60 40
ROME 87 70 87 68 / 50 40 60 10
PEACHTREE CITY 89 70 87 69 / 30 20 60 30
VIDALIA 93 74 94 74 / 30 20 30 40
&&
.FFC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS GOODLAND KS
706 AM MDT WED JUL 23 2014
.UPDATE...
ISSUED AT 700 AM MDT WED JUL 23 2014
STRONG THUNDERSTORMS HAVE REDEVELOPED TO THE NORTH ACROSS WEST
CENTRAL NEBRASKA ALONG AND NORTH OF AREA OF H8 TO H75 PERSISTENT
WAA. WHILE FORCING GENERALLY DECREASES INTO THE CWA AS WINDS ALOFT
DIMINISH...AM CONCERNED ABOUT CURRENT RAP DEPICTION OF NEARLY 3000
J/KG OF ELEVATED CAPE AND LITTLE CINH LOCATED AROUND H725. WHILE
FORCING MAY BE DIMINISHED...WILL NOT BE OUT OF THE QUESTION FOR
THESE STORMS TO PROPAGATE INTO THIS POTENTIALLY UNSTABLE AIRMASS.
HAVE INCREASED/REFINED POPS TO ACCOUNT FOR THIS BUT THERE STILL IS
A LOT OF QUESTION WITH REGARDS TO HOW FAR SOUTH STORMS WILL MAKE
IT. GIVEN AFOREMENTIONED INSTABILITY...SEVERE STORMS WILL BE
POSSIBLE THROUGH THE MORNING HOURS.
UPDATE ISSUED AT 552 AM MDT WED JUL 23 2014
NO MAJOR UPDATES FOR THIS ESTF ISSUANCE. CONTINUING MENTION OF
PATCHY FOG IN FORECAST AS SPOTTY FOG SHOWING UP IN LATEST OBS.
LATEST RADAR LOOP SHOWING ISOLATED/SCATTERED RW/TRW ALONG PORTIONS
OF OUR CWA...SO HAVE LEFT IN CURRENT MENTION OF PRECIPITATION.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 215 AM MDT WED JUL 23 2014
SCATTERED THUNDERSTORMS ALONG NORTHERN BORDER ZONES THIS MORNING IN
CONNECTION WITH FRONTAL BOUNDARY...REMNANTS WHICH HAS BEEN
MEANDERING OVER KANSAS/NEBRASKA OVERNIGHT. MOST OF THE PRECIPITATION
WILL OCCUR OUT OF CWA...BUT HAVE INCLUDED SL CHANCE POPS FOR TRW
THRU 14Z-15Z FOR NORTHERN ZONES. HIGH DEWPTS AROUND THE AREA
CREATING MUGGY CONDITIONS WHICH COULD TRANSLATE INTO A FEW HOURS OF
PATCHY FOG THIS MORNING UNTIL SUNRISE SO HAVE MENTIONED FOR ALL
AREAS. MID/UPPER LEVEL RIDGE WILL RE-ASSERT ITSELF AGAIN ACROSS THE
CWA TODAY INTO TONIGHT. WITH THIS...EXPECTING YET ANOTHER HOT DAY
ACROSS THE AREA...WITH MID TO UPPER 90S FOR HIGHS...AND MID TO
UPPER 60S FOR OVERNIGHT LOWS. ONLY WESTERN ZONES WILL POTENTIALLY
SEE A LATE DAY REPRIEVE AS ISOLATED TRW MAY DEVELOP AS LEE-SIDE
TROUGH SETS UP ALONG EASTERN ROCKIES.
.LONG TERM...(THURSDAY THROUGH TUESDAY)
ISSUED AT 215 AM MDT WED JUL 23 2014
FOR THE THURSDAY THROUGH FRIDAY NIGHT PERIODS...THE CWA WILL
CONTINUE TO SEE MAINLY HOT AND DRY CONDITIONS AS BROAD H5/H7 RIDGE
REMAINS OVER THE AREA. DOWN TO THE SURFACE...LEE-SIDE TROUGH
DEVELOPS AND MOVES ACROSS THE REGION THURSDAY/THURSDAY NIGHT WITH A
WEAK SHORTWAVE WORKING OVER TOP OF RIDGE...AS MODELS DO SHOW SOME
FLATTENING POTENTIAL FRIDAY/FRIDAY NIGHT WHICH MAY BRING A CHANCE
FOR CONVECTION. WITH 925 MB TEMPERATURES REMAINING IN THE +35C TO
+40C...FORECASTED HIGHS WILL STAY IN THE 95-100 DEGREE RANGE FOR
BOTH DAYS. OVERNIGHT LOWS WILL STAY IN 60S...WARMEST IN EASTERN
ZONES. BOTH HIGHS/LOWS WILL BE AFFECTED AT TIMES FROM EXPECTED CLOUD
COVER/PRECIP...BUT WILL BE LOCALIZED AS WILL BE KEEPING SL CHANCE
POPS IN FOR TRW. BEST CHANCES FOR CONVECTION THURSDAY/THURSDAY NIGHT
WILL BE SPLIT DUE TO SLOW MOVEMENT OF TROUGH OFF THE ROCKIES...AND
FOR FRIDAY/FRIDAY NIGHT THE MAIN FOCUS WILL SHIFT TO NORTHERN
SECTIONS DUE TO TRACK OF SHORTWAVE.
COOLING TREND LATE THIS WEEKEND INTO NEXT WEEK WITH A FEW CHANCES
FOR PRECIP ALONG THE WAY. HAVE GENERALLY LOWERED POPS ACROSS THE
FORECAST PERIOD...BUT AM STILL CONFIDENT WE WILL SEE SOME CONVECTIVE
ACTIVITY MOST DAYS. UPPER FLOW WILL BE MAINLY OUT OF THE NORTHWEST
AS AN UPPER HIGH OVER THE FOUR CORNERS REGION RETROGRADES WEST A BIT
AND A RIDGE DEVELOPS ACROSS THE GREAT BASIN REGION EARLY NEXT WEEK.
COLD FRONT ARRIVING OVER THE WEEKEND WILL BRING RELATIVELY COOLER
TEMPS AND /THANKFULLY/ LOWER DEW POINTS.
SATURDAY...WEAK IMPULSES MOVING ACROSS THE COLORADO ROCKIES COULD
PROVIDE AMPLE LARGE SCALE LIFT FOR ISOLATED STORMS TO DEVELOP DURING
THE DAY. PREVIOUS GUIDANCE HAD INDICATED SUFFICIENT INSTABILITY FOR
STRONG TO SEVERE THUNDERSTORMS...BUT IT SEEMS THE ECMWF IS NOW
LEANING TOWARDS WHAT HAS RECENTLY BEEN A VERY DRY GFS. GEM REMAINS
STEADFAST IN SOME INSTABILITY DUE TO BETTER MOISTURE THROUGHOUT THE
COLUMN...SO WILL CONTINUE TO KEEP SOME POPS IN PLACE DESPITE THE DRY
GFS AND ECMWF. SATURDAY NIGHT IS A DIFFERENT STORY...WITH
GEFS/ECMWF/GEM INDICATING INCREASED MOISTURE AVAILABILITY AS COLD
FRONT PUSHES THROUGH FROM THE NORTH/NORTHWEST. THIS SHOULD SUPPORT
AT LEAST ISOLATED STORMS LATE IN THE DAY...POSSIBLY LASTING THROUGH
THE NIGHT. UPPER LEVEL SUPPORT FOR LARGE SCALE LIFT ACROSS THE
LATEST GUIDANCE IS NOT AS SUPPORTIVE ON LATEST GUIDANCE AS PREVIOUS
RUNS HAVE BEEN...SO A BIT LOWER CONFIDENCE THAN USUAL FOR OVERNIGHT
STORMS.
SUNDAY...COOLER FOLLOWING FROPA. SOME CLOUDS DURING THE MORNING
CLEARING OUT TO A MOSTLY SUNNY DAY. SOME AFTERNOON CONVECTION
POSSIBLE BEHIND THE FRONT...THOUGH THERE IS CHANCE THE MODERATELY
STRONG CAP COULD PREVENT DEVELOPMENT. GUIDANCE IN GOOD AGREEMENT ON
AN INVERTED-V SOUNDING...SO WITH ANY STORMS THAT DEVELOP GUSTY WINDS
COULD BE POSSIBLE. A FEW STORMS COULD LAST INTO THE EVENING...ENDING
BEFORE MIDNIGHT. HIGHS LIMITED TO THE MID/UPPER 80S. OVERNIGHT LOWS
DIPPING BELOW 60 IN SOME SPOTS FOR THE FIRST TIME IN A WEEK.
MONDAY AND TUESDAY...SLIGHT CHANCE FOR SHOWERS/STORMS BOTH
DAYS...WITH THE BETTER CHANCE FOR PRECIP ON TUESDAY. A NUMBER OF
WEAK MID-LEVEL IMPULSES WILL MOVE ACROSS THE CENTRAL ROCKIES AND
INTO THE CENTRAL HIGH PLAINS IN THE NORTH-NORTHWESTERLY FLOW. IN
THIS FAVORABLE ENVIRONMENT EXPECT MOSTLY TERRAIN-BASED STORMS TO
FIRE IN THE DAY AND MOVE EAST INTO THE AREA DURING THE LATE
AFTERNOON. LOW LEVEL FLOW WILL BE OUT OF THE SOUTH WHICH WILL
INCREASE LOW LEVEL MOISTURE...AND THUS PROVIDE SOME INSTABILITY FOR
STORMS TO WORK WITH. 0-6KM BULK SHEAR IN THE 30-40KT RANGE COULD
HELP SUSTAIN STORMS THROUGH THE LATE NIGHT HOURS. HIGHS IN THE
MID/UPPER 80S.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z THURSDAY MORNING)
ISSUED AT 523 AM MDT WED JUL 23 2014
FOR GLD/MCK THROUGH 14Z...MIX OF CONDITIONS FROM MVFR DOWN TO LIFR
WITH FOG 4-6SM AND CEILINGS RANGING FROM BKN004-010. AFT 14Z VFR
CONDITIONS WITH FEW020-030 SCT200-300. VCTS POSSIBLE FOR GLD 01Z-
06Z WITH SCT060CB. WINDS RANGE FROM ENE TO ESE 5-10KTS BECM SSE
10-20KTS BY 14Z.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
UPDATE...JRM
SHORT TERM...JN
LONG TERM...JJM
AVIATION...JN
AREA FORECAST DISCUSSION
NWS TWIN CITIES/CHANHASSEN MN
553 AM CDT WED JUL 23 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 338 AM CDT WED JUL 23 2014
MOST IMPRESSIVE FEATURE ON THE H5 CHART LAST NIGHT WAS THE RIDGE
CENTERED OVER COLORADO...WHERE THE H5 HEIGHT MEASURED AT GRAND
JUNCTION REACHED THE LOFTY HEIGHT OF 6000 M. ITS ASSOCIATED RIDGE
AXIS EXTENDS NORTH INTO SASKATCHEWAN...WITH CONVERGENT NW FLOW NOTED
FROM MANITOBA INTO NW MN...HENCE THE 1028 MB SFC HIGH THAT IS
CENTERED OVER THE MANITOBA LAKES THIS MORNING. DURING THE SHORT
TERM...THE UPPER RIDGE WILL SHIFT EAST INTO THE UPPER MISS VALLEY
WHILE THE SFC HIGH WILL SHIFT OVER TO LAKE MICHIGAN BY 12Z THU.
FOR TODAY...NAM CU RULE SHOWS SCT-BKN CU FIELD DEVELOPING ACROSS WRN
WI...TRAILING OFF TO LITTLE IF ANY CU FOR WRN MN. HOWEVER...WRN MN
WILL HAVE TO DEAL WITH REMNANT CLOUD COVER FROM UPPER WAVES ROTATING
AROUND THE COLORADO RIDGE. IN PARTICULAR...THE RAP SHOWS THE WAVE
CURRENTLY OVER CENTRAL NODAK WORKING TOWARD WRN MN BY THE AFTERNOON.
DRY LOW LEVELS COURTESY THE 1028 MB HIGH WILL MAKE IT TOUGH TO GET
THE PRECIP IN THE MINOT AREA INTO MN...THOUGH A FEW SPRINKLES CAN
NOT BE COMPLETELY RULED OUT. DID BOOST SKY COVER WEST TO ACCOUNT FOR
THIS WAVE AND ITS ASSOCIATED CLOUD COVER THOUGH. H85 TEMPS WILL BE
FAIRLY UNIFORM AROUND 12/13C...WHICH HAS BEEN PRETTY GOOD THIS
SUMMER AT PRODUCING HIGHS IN THE 77 TO 81 DEGREE RANGE...SO NO BIG
CHANGES WERE NEEDED TO THE GOING FORECAST.
TONIGHT...AS THE RIDGE WORKS ACROSS WI...RETURN FLOW WILL BE
STRENGTHENING ACROSS THE DAKOTAS...WITH ISENTROPIC LIFT AND THETA-E
ADVECTION BOTH BLOSSOMING. LLJ ORIENTATION FAVORS ACTIVITY
DEVELOPING ALONG THE MO RIVER TONIGHT...MAKING ABOUT AS FAR EAST AS
SE SODAK...SO KEPT THE FORECAST DRY THROUGH 12Z THU...THOUGH WE
PROBABLY WILL NOT HAVE TO WAIT VERY LONG ON THU TO START SEEING
PRECIP PUSH INTO THE UPPER MN VALLEY. OVER WI...WITH THE HIGH
OVERHEAD THE QUESTION BECOMES HOW LOW TO GO...ALONG WITH THE
POTENTIAL FOR FOG. DID NUDGE LOWS DOWN A DEGREE OR TWO CLOSER TO THE
CONSENSUS RAW MODEL BLEND /BEST PERFORMING GUIDANCE OVER THE LAST
WEEK/...WHICH HAS LADYSMITH DIPPING INTO THE UPPER 40S. THE FOG
POTENTIAL IS A BIT TOUGHER TO PIN DOWN AT THIS POINT...BUT CERTAINLY
IF WE DO SEE LOWS DOWN AROUND 50...SOME PATCHY FOG...ESPECIALLY NEAR
BODIES OF WATER WILL CERTAINLY BE POSSIBLE.
.LONG TERM...(THURSDAY THROUGH TUESDAY)
ISSUED AT 338 AM CDT WED JUL 23 2014
SCATTERED SHOWERS AND THUNDERSTORMS ARE EXPECTED TO BE OVER
EASTERN DAKOTAS AT DAYBREAK ON THURSDAY ALONG AND AHEAD OF A
STRENGTHENING BAROCLINIC ZONE STRETCHING NW-SE ACROSS THE NORTHERN
PLAINS. THE SHOWERS AND THUNDERSTORMS WILL SPREAD ACROSS THE MN
CWA DURING THE DAY AND INTO WESTERN WI BY EVENING AS THE
FRONTOGENETIC ZONE MOVES EAST. THE FA IS IN THE RIGHT ENTRANCE REGION
OF AN 80 PLUS KNOT JET SEGMENT ACROSS THE WESTERN GREAT LAKES
WITH UPPER LEVEL DIVERGENCE INDICATED. BY THE END OF THE DAY...A
COUPLED JET STRUCTURE BEGINS TO DEVELOP...ALONG WITH INCREASING
DIVERGENCE...AS THE LEFT EXIT REGION OF A NEW SEGMENT ARRIVES FROM
THE EASTERN DAKOTAS. THIS FEATURE THEN PASSES ACROSS SOUTHERN
AREAS OF MN AND IA THURSDAY NIGHT. WHILE THIS IS OCCURRING...LOW
LEVEL MOISTURE TRANSPORT IN THE CENTRAL PLAINS VEERS INTO IA AND
SOUTHERN MN. THIS SHOULD RESULT IN THUNDERSTORMS INCREASING IN
COVERAGE ACROSS THE AFOREMENTIONED AREAS ALONG WITH THE POTENTIAL
FOR HEAVY RAIN. THE ECMWF HAS A GREAT HANDLE ON THIS SITUATION
WHILE OTHER DETERMINISTIC MODELS STRUGGLE TO DEVELOP MUCH
PRECIPITATION...WHICH IS A CHARACTERISTIC OF WARM AIR ADVECTION
EVENTS. HENCE...CHANCE POPS DURING THE DAY THURSDAY INCREASE TO
LIKELY THURSDAY NIGHT ACROSS SOUTHERN AREAS OF MN.
THE PRECIPITATION WILL MOVE ESE FRIDAY MORNING WITH A DRYING TREND
FRIDAY AFTERNOON AS A FAIRLY STRONG SHORT WAVE MOVES THROUGH.
HOWEVER...A WEAK SURFACE FRONT WILL SLOWLY TRAVERSE THE FA FRIDAY
AFTERNOON AND NIGHT WITH SOME SMALL POPS REMAINING. MUCH OF
SATURDAY LOOKS DRY BEFORE A COMPACT VERTICALLY STACKED LOW
PRESSURE SYSTEM SWINGS SOUTHEAST ACROSS THE UPPER MISSISSIPPI
VALLEY REGION SATURDAY NIGHT AND SUNDAY. THIS NECESSITATES MORE
CHANCE POPS FOR THE LATTER HALF OF THE WEEKEND. HIGHS FROM
THURSDAY TO SATURDAY WILL BE SLOWLY RISING FROM AROUND 80 TO THE
LOWER AND MIDDLE 80S RESPECTIVELY. HIGHS WILL THEN TREND DOWN INTO
THE MIDDLE TO UPPER 70S FOR SUNDAY AND AT LEAST THE FIRST HALF OF
NEXT WEEK. THE REASON FOR THE EXTENDED COOL DOWN IS A DEEPENING
EASTERN NORTH AMERICA TROUGH WITH A BUILDING RIDGE IN THE WEST.
LONGER RANGE MODEL SOLUTIONS HAVE BEEN VERY CONSISTENT ON THIS
DEVELOPMENT WITH A H5 CLOSED LOW JUST NORTH OF THE GREAT LAKES
NEXT WEDNESDAY. H5 HEIGHTS ACROSS THE GREAT LAKES AND OHIO VALLEY
ARE FORECAST TO BE 2 TO 3 STANDARD DEVIATIONS BELOW NORMAL.
ACCOMPANYING THE COOLER TEMPERATURES WILL BE MAINLY DRY CONDITIONS.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z THURSDAY MORNING)
ISSUED AT 548 AM CDT WED JUL 23 2014
HIGH PRESSURE WILL MOVE ACROSS MN AND INTO WI THIS
PERIOD...RESULTING IN QUIET CONDITIONS WITH LIGHT WINDS. VFR
CONDITIONS WILL DOMINATE...WITH THE ONLY EXCEPTION BEING THE
POTENTIAL FOR FOG THIS MORNING AND ESPECIALLY THURSDAY MORNING OVER
IN EAU...WHEN THE CENTER OF THE HIGH WILL BE NEAR CENTRAL WI. THIS
WILL MAINLY BE A RIVER VALLEY FOG THOUGH...HENCE THE PREVAILING MVFR
WITH A TEMPORARY LIFR VIS THU MORNING. OTHER THAN THAT...CU FIELD
WILL DEVELOP OVER ERN MN/WRN WI LATE THIS MORNING...STARTING OUT
NEAR 4K FEET...BUT CLIMBING TO NEAR 6K FEET BY THE LATE AFTERNOON.
OUT WEST...MID LEVEL CLOUDS OUT IN THE DAKOTAS WILL SPILL INTO WRN
MN BY THE AFTERNOON...BUT EXPECTING NOTHING MORE THAN THAT FROM THE
NODAK DISTURBANCE.
KMSP...HIGH CONFIDENCE TAF WITH VFR CONDITIONS PREVAILING WITH LIGHT
NORTH WINDS TODAY...CALM WINDS TONIGHT...FOLLOWED BY LIGHT SE WINDS
THURSDAY.
/OUTLOOK FOR KMSP/
THU...VFR. CHANCE MVFR CONDS W/ TSRA LATE AFTERNOON AND
OVERNIGHT. WINDS SE AT 10KTS.
FRI...VFR. CHANCE TSRA. WINDS SSE AT 5-10KTS.
SAT...VFR. WINDS W AT 10KTS.
KMSP...
/OUTLOOK FOR KMSP/
&&
.MPX WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...NONE.
&&
$$
SHORT TERM...MPG
LONG TERM...RAH
AVIATION...MPG
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
1035 AM EDT WED JUL 23 2014
.SYNOPSIS...
A COLD FRONT WILL PUSH SOUTHEAST ACROSS THE COMMONWEALTH LATE
TODAY AND TONIGHT. A REFRESHING...COOLER AND LESS HUMID AIRMASS
WILL OVERSPREAD THE COMMONWEALTH FOR THE END OF THE WEEK INTO THE
WEEKEND.
&&
.NEAR TERM /UNTIL 7 PM THIS EVENING/...
10 AM UPDATE...
RADAR ECHOES IN NW PA NOT BELOW FL120...SO LITTLE PRECIP FORSEEN
THERE UNTIL ANY DIURNAL CONVECTION FLARES UP ALONG THE BEST WIND
SHIFT/DEWPOINT BOUNDARY WHICH IS JUST CROSSING THE LAKES NOW.
ALSO...TEMPS RUNNING A FEW DEGS AHEAD OF THE CURVE AT THIS POINT
WITH STRONG SUNSHINE OVER THE SERN 2/3RDS OF THE AREA.
THUS...CONVECTIVE TEMPS SHOULD BE REACHED VERY SOON - ESP ON THE
HIGHER HILLS OF THE SERN HALF OF THE AREA. THIS COMBINE WITH A BIT
OF A PRE-FRONTAL TROUGH EVIDENT IN THE SFC PRESSURES AT 15Z WILL
CREATE SCT SHRA IN THE SE BY 18Z. EXPECT THE WARM AIR ALOFT WHICH
IS SEEN IN BOTH BALLOON AND MODEL SOUNDINGS TO KEEP THE CONVECTION
SHORT UNTIL MID AFTERNOON. HOWEVER...THE INSTABILITY AND LLVL
MOISTURE SHOULD BE ENOUGH TO GENERATE VERY LARGE CAPES THIS AFTN
AND EARLY THIS EVENING. WILL TWEAK POPS WITH AN EYE TOWARD MORE IN
THE SE AND LESS IN THE NW FOR THE FIRST FEW HRS OF THE PERIOD.
TEMPS WILL PROBABLY RISE ABOVE 90F IN MANY LOCATION IN THE EASTERN
VALLEYS...EXCEPT WHERE THE EARLY AFTN ISOLD/SCT CONVECTION COOLS
THEM OFF.
PREV...
WEAK RIDGING OVER THE REGION AT THE SURFACE AND ALOFT...COMBINED
WITH VERY WARM MID LEVEL TEMPS OF 9-11C WILL KEEP CONDITIONS
MAINLY CLEAR BUT MUGGY INTO THE LATE MORNING HOURS.
CURRENT DEWPOINTS IN THE MID TO UPPER 60S ARE A FEW DEG SHY OF
THE EXPECTED MIN TEMPS AROUND SUNRISE.
CIRRUS BLOWOFF FROM A WEAKENING LINE OF SHOWERS AND THUNDERSTORMS
OVER LAKE ERIE WILL OVERSPREAD THE NW MTNS THIS MORNING...BUT
THEN DISSIPATE FOR THE MIDDAY HOURS BEFORE NEW CONVECTION
INITIATES ALONG/AHEAD OF AN APPROACHING COLD FRONT.
THE BKN LINE OF SHRA/TSRA SLIDING SE ACROSS CENTRAL LAKE ERIE ATTM
IS OVER LOCALLY COOLER AND MORE STABLE LLVLS...AND IS PROGGED BY
THE LAST FEW RUNS OF THE HRRR TO STEADILY WEAKEN...AND EVEN
DISSIPATE AS IT MOVES ONTO THE SOUTH SHORE DURING THE NEXT
FEW HOURS AND ENCOUNTERS THE VERY STRONG MID-LEVEL CAP ACROSS
NWRN PENN. 15-MINUTE LIGHTNING FREQUENCY HAS DROPPED OFF
DRAMATICALLY OVER THE PAST HOUR. STILL PAINTED CHC POPS FOR
SHOWERS OR A RUMBLE OF THUNDER ACROSS NW WARREN COUNTY AROUND 12Z
SINCE EARLIER RUNS OF THE HRRR HAD NO SIGN OF CONVECTION EVEN
REACHING THE CENTRAL WATERS OF LAKE ERIE ATTM.
A DRY START TO THE DAY AND MAINLY SUNNY SKIES ACROSS ALL BUT THE
FAR NW ZONES...WILL GIVE WAY TO INCREASING CHANCES FOR SHOWERS
AND THUNDERSTORMS THIS AFTERNOON AS LARGE SCALE FORCING INCREASES
ASSOCIATED WITH THE APPROACHING COLD FRONT.
SPC HAS MAINTAINED A /SEE TEXT/ FOR ALL OF PENN WITHIN THEIR DAY
1 CONVECTIVE OUTLOOK...WITH EASTERN NEW YORK AND NEW ENGLAND UNDER
THE GUN FOR A SLIGHT RISK OF SVR TSRA GIVEN THE BETTER COMBINATION
OF STRONGER DEEP LAYER SHEAR AND CAPE. STILL...MODERATE-HIGH SFC
BASED CAPE IN EXCESS OF 2000 J/KG...COMBINED WITH ABOUT 20 KTS OF
0-6KM BULK SHEAR SHOULD BE SUFFICIENT FOR A FEW OCCURRENCES OF
DAMAGING MICROBURSTS AND HAIL ACROSS THE CWA THIS AFTERNOON INTO
THIS EVENING.
THE LOW-LEVEL...WSW DOWNSLOPE FLOW/COMPRESSIONAL WARMING OF THE
AIRMASS AHEAD OF THE CFRONT...WILL LEAD TO THE HIGHEST TEMPS OF
THE WEEK. AFTERNOON MAX TEMPS WILL RANGE FROM THE LOWER 80S
ACROSS THE HIGH TERRAIN OF THE NORTH AND WEST...TO THE MID AND
UPPER 80S IN THE CENTRAL VALLEYS...AND LOWER 90S IN THE GREATER
YORK/HARRISBURG AREA.
&&
.SHORT TERM /7 PM THIS EVENING THROUGH 6 AM THURSDAY/...
THE FOCUS FOR SHOWERS AND THUNDERSTORMS /SOME WITH HEAVY
RAIN...GUSTY WINDS...FQT LIGHTNING AND EVEN SOME FAIRLY LARGE
HAIL/ WILL OCCUR ACROSS THE LOWER SUSQ VALLEY THIS EVENING...
WHILE THE FAR NW SEES SHOWERS DECREASE/MOVE OFF TO THE SOUTH AS
THE CFRONT PUSHES THROUGH THE KBFD AREA LATE THIS AFTERNOON...AND
REACHES THE CENTRAL ZONES AOB 00Z THUR. SCATTERED SHOWERS AND A
STRAY TSRA WILL LINGER ACROSS THE CENTRAL RIDGE AND VALLEY REGION
THROUGH EARLY THIS EVENING.
24-HOUR...STORM TOTAL RAINFALL WILL BE ABOUT 4-5 TENTHS OF AN
INCH...WITH THE BULK OF IT FALLING FROM JUST ONE OR TWO
THUNDERSTORMS. GIVEN THE ANOMALOUSLY HIGH PWATS OF 1.5-2 INCHES
ACROSS THE STATE...THERE IS A CHANCE FOR LOCALLY HEAVY RAINFALL OF
OVER 1 INCH.
TEMPS TONIGHT WILL STILL BE QUITE MUGGY IN THE SOUTHEAST. LOWS
WILL RANGE FROM THE UPPER 60S ACROSS THE LOWER SUSQ REGION...TO
THE MUCH MORE COMFORTABLE UPPER 50S ACROSS THE NORTHERN MTNS.
&&
.LONG TERM /THURSDAY THROUGH TUESDAY/...
OVERALL SCENARIO REMAINS UNCHANGED IN THE LONG TERM PERIOD AS A
LARGE UPPER RIDGE BUILDING OVER THE FOUR CORNERS REGION IS
FORECAST TO EXPAND NORTH AND EAST INTO THE ROCKIES AND PLAINS
DURING THE PERIOD. DOWNSTREAM...THIS WILL LEAD TO LONG WAVE
TROFFING OVER THE EASTERN THIRD OF THE COUNTRY. UPPER LOW TO THE
EAST OF HUDSON BAY WILL BE STRENGTHENED AT TIMES BY SHORTWAVE
ENERGY IN THE STRONGER JET STREAM FLOW ACROSS CANADA. SOUTHWARD
EXTENSION OF THIS LOW/TROF WILL AT TIMES DURING THE PERIOD
STRENGTHENING THE TROFFING ACROSS THE NORTHEASTERN U.S./OUR
REGION. THE TREND OF MEDIUM RANGE MODEL GUIDANCE IS FOR
STRONGER/DEEPER TROFFING DOWNSTREAM ACROSS THE EASTERN
U.S...DEVELOPING AN ALMOST FULL LATITUDE TROF EXTENDING FROM THE
EASTERN CANADA LOW SWD TO FLORIDA. THIS WILL LIKELY SERVE TO
EXPAND AND PROLONG THE CHANCES FOR PCPN THIS WEEKEND.
GUIDANCE FORECASTS CONTINUE TO BRING A FRONT AND INCREASED
CHANGES FOR PRECIPITATION TOWARD PA IN THE WEDNESDAY/THURSDAY TIME
FRAME AND SHOW A SECOND...POTENTIALLY STRONGER SYSTEM LATE NEXT
WEEKEND. THE TREND OF STRONGER TROUGHING MENTIONED ABOVE HAS LEAD
TO SLOWER ARRIVAL AND DEPARTURE OF THE FRONTAL SYSTEM IN THE DAILY
PROGS. THE ECMWF IN LATEST RUN HAS SLOWED UP THE PROGRESSION OF
THIS UPPER LEVEL LOW...WHERE THE GFS OPERATIONAL AND ENSEMBLES
HAVE SPED UP ITS PROGRESSION THROUGH THE GREAT LAKES REGION. A
WARM FRONT WILL BE ON THE DOORSTEP OF PA SUNDAY...AS THE EC
CONTINUES TO SLOW ITS PROGRESSION SO EXPECT THE WARM FRONT TO MOVE
IN CLOSER TO MIDDAY SUNDAY. HAVE THUS ADJUSTED POPS/TIME.
ASSOCIATED COLD FRONT DOES NOT CROSS THE STATE TIL MONDAY...WHERE
SURPRISINGLY AT THIS POINT...THE EC AND GFS COME CLOSELY IN PHASE.
THIS LARGE UPPER LEVEL LOW COULD BECOME QUASI STATIONARY OVER
SOUTHERN CANADA...GREAT LAKES REGION WHICH COULD LEAD TO A
POTENTIAL PROLONGED PERIOD OF SHOWERS AND THUNDERSTORM THROUGH THE
MIDDLE OF NEXT WEEK.
&&
.AVIATION /15Z WEDNESDAY THROUGH SUNDAY/...
AFTER A QUIET START TO THE DAY...SCT TO NMRS SHWRS AND TSTMS
WILL DEVELOP THIS AFTN INTO THE EVE ALONG AND AHEAD OF A COLD
FRONT SHIFTING SEWD FROM THE GREAT LAKES. CVRG PROJECTED TO BE
GREATEST OVER THE CNTRL AND ERN PRTNS OF THE AIRSPACE WITH SOME
STG TO MARGINALLY SVR STORMS POSSIBLE. PREVAILING CONDS WILL BE
VFR WITH BRIEF MVFR-IFR VIS REDUCTIONS IN TSRA. WND SHIFT FROM SW
TO NW BY TONIGHT WITH MAIN PCPN ACTIVITY BCMG CONFINED TO SERN
AREAS INTO THU. MVFR CIGS SEEM PROBABLE OVER WRN SXNS LATE TNGT IN
POST- FRONTAL UPSLOPE NW FLOW.
OUTLOOK...
THU...SCT TSTM IMPACTS PSBL SERN AIRFIELDS AS COLD FRONT SLOWS
ALONG THE MID-ATLC COAST.
FRI...PATCHY MORNING FOG...OTHERWISE VFR/NO SIG WX.
SAT...PATCHY MORNING FOG...OTHERWISE VFR. ISOLD PM TSTM PSBL.
SUN...TSTM IMPACTS LKLY AS WARM FRONT LIFTS NWD ACRS AIRSPACE.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...LAMBERT
NEAR TERM...DANGELO/LAMBERT
SHORT TERM...LAMBERT
LONG TERM...LAMBERT/CERU
AVIATION...STEINBUGL
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
719 AM EDT WED JUL 23 2014
.SYNOPSIS...
A COLD FRONT WILL PUSH SOUTHEAST ACROSS THE COMMONWEALTH LATE
TODAY AND TONIGHT. A REFRESHING...COOLER AND LESS HUMID AIRMASS
WILL OVERSPREAD THE COMMONWEALTH FOR THE END OF THE WEEK INTO THE
WEEKEND.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
WEAK RIDGING OVER THE REGION AT THE SURFACE AND ALOFT...COMBINED
WITH VERY WARM MID LEVEL TEMPS OF 9-11C WILL KEEP CONDITIONS
MAINLY CLEAR BUT MUGGY INTO THE LATE MORNING HOURS.
CURRENT DEWPOINTS IN THE MID TO UPPER 60S ARE A FEW DEG SHY OF
THE EXPECTED MIN TEMPS AROUND SUNRISE.
CIRRUS BLOWOFF FROM A WEAKENING LINE OF SHOWERS AND THUNDERSTORMS
OVER LAKE ERIE WILL OVERSPREAD THE NW MTNS THIS MORNING...BUT
THEN DISSIPATE FOR THE MIDDAY HOURS BEFORE NEW CONVECTION
INITIATES ALONG/AHEAD OF AN APPROACHING COLD FRONT.
THE BKN LINE OF SHRA/TSRA SLIDING SE ACROSS CENTRAL LAKE ERIE ATTM
IS OVER LOCALLY COOLER AND MORE STABLE LLVLS...AND IS PROGGED BY
THE LAST FEW RUNS OF THE HRRR TO STEADILY WEAKEN...AND EVEN
DISSIPATE AS IT MOVES ONTO THE SOUTH SHORE DURING THE NEXT
FEW HOURS AND ENCOUNTERS THE VERY STRONG MID-LEVEL CAP ACROSS
NWRN PENN. 15-MINUTE LIGHTNING FREQUENCY HAS DROPPED OFF
DRAMATICALLY OVER THE PAST HOUR. STILL PAINTED CHC POPS FOR
SHOWERS OR A RUMBLE OF THUNDER ACROSS NW WARREN COUNTY AROUND 12Z
SINCE EARLIER RUNS OF THE HRRR HAD NO SIGN OF CONVECTION EVEN
REACHING THE CENTRAL WATERS OF LAKE ERIE ATTM.
A DRY START TO THE DAY AND MAINLY SUNNY SKIES ACROSS ALL BUT THE
FAR NW ZONES...WILL GIVE WAY TO INCREASING CHANCES FOR SHOWERS
AND THUNDERSTORMS THIS AFTERNOON AS LARGE SCALE FORCING INCREASES
ASSOCIATED WITH THE APPROACHING COLD FRONT.
SPC HAS MAINTAINED A /SEE TEXT/ FOR ALL OF PENN WITHIN THEIR DAY
1 CONVECTIVE OUTLOOK...WITH EASTERN NEW YORK AND NEW ENGLAND UNDER
THE GUN FOR A SLIGHT RISK OF SVR TSRA GIVEN THE BETTER COMBINATION
OF STRONGER DEEP LAYER SHEAR AND CAPE. STILL...MODERATE-HIGH SFC
BASED CAPE IN EXCESS OF 2000 J/KG...COMBINED WITH ABOUT 20 KTS OF
0-6KM BULK SHEAR SHOULD BE SUFFICIENT FOR A FEW OCCURRENCES OF
DAMAGING MICROBURSTS AND HAIL ACROSS THE CWA THIS AFTERNOON INTO
THIS EVENING.
THE LOW-LEVEL...WSW DOWNSLOPE FLOW/COMPRESSIONAL WARMING OF THE
AIRMASS AHEAD OF THE CFRONT...WILL LEAD TO THE HIGHEST TEMPS OF
THE WEEK. AFTERNOON MAX TEMPS WILL RANGE FROM THE LOWER 80S
ACROSS THE HIGH TERRAIN OF THE NORTH AND WEST...TO THE MID AND
UPPER 80S IN THE CENTRAL VALLEYS...AND LOWER 90S IN THE GREATER
YORK/HARRISBURG AREA.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 AM THURSDAY/...
THE FOCUS FOR SHOWERS AND THUNDERSTORMS /SOME WITH HEAVY
RAIN...GUSTY WINDS...FQT LIGHTNING AND EVEN SOME FAIRLY LARGE
HAIL/ WILL OCCUR ACROSS THE LOWER SUSQ VALLEY THIS EVENING...
WHILE THE FAR NW SEES SHOWERS DECREASE/MOVE OFF TO THE SOUTH AS
THE CFRONT PUSHES THROUGH THE KBFD AREA LATE THIS AFTERNOON...AND
REACHES THE CENTRAL ZONES AOB 00Z THUR. SCATTERED SHOWERS AND A
STRAY TSRA WILL LINGER ACROSS THE CENTRAL RIDGE AND VALLEY REGION
THROUGH EARLY THIS EVENING.
24-HOUR...STORM TOTAL RAINFALL WILL BE ABOUT 4-5 TENTHS OF AN
INCH...WITH THE BULK OF IT FALLING FROM JUST ONE OR TWO
THUNDERSTORMS. GIVEN THE ANOMALOUSLY HIGH PWATS OF 1.5-2 INCHES
ACROSS THE STATE...THERE IS A CHANCE FOR LOCALLY HEAVY RAINFALL OF
OVER 1 INCH.
TEMPS TONIGHT WILL STILL BE QUITE MUGGY IN THE SOUTHEAST. LOWS
WILL RANGE FROM THE UPPER 60S ACROSS THE LOWER SUSQ REGION...TO
THE MUCH MORE COMFORTABLE UPPER 50S ACROSS THE NORTHERN MTNS.
&&
.LONG TERM /THURSDAY THROUGH TUESDAY/...
OVERALL SCENARIO REMAINS UNCHANGED IN THE LONG TERM PERIOD AS A
LARGE UPPER RIDGE BUILDING OVER THE FOUR CORNERS REGION IS
FORECAST TO EXPAND NORTH AND EAST INTO THE ROCKIES AND PLAINS
DURING THE PERIOD. DOWNSTREAM...THIS WILL LEAD TO LONG WAVE
TROFFING OVER THE EASTERN THIRD OF THE COUNTRY. UPPER LOW TO THE
EAST OF HUDSON BAY WILL BE STRENGTHENED AT TIMES BY SHORTWAVE
ENERGY IN THE STRONGER JET STREAM FLOW ACROSS CANADA. SOUTHWARD
EXTENSION OF THIS LOW/TROF WILL AT TIMES DURING THE PERIOD
STRENGTHENING THE TROFFING ACROSS THE NORTHEASTERN U.S./OUR
REGION. THE TREND OF MEDIUM RANGE MODEL GUIDANCE IS FOR
STRONGER/DEEPER TROFFING DOWNSTREAM ACROSS THE EASTERN
U.S...DEVELOPING AN ALMOST FULL LATITUDE TROF EXTENDING FROM THE
EASTERN CANADA LOW SWD TO FLORIDA. THIS WILL LIKELY SERVE TO
EXPAND AND PROLONG THE CHANCES FOR PCPN THIS WEEKEND.
GUIDANCE FORECASTS CONTINUE TO BRING A FRONT AND INCREASED
CHANGES FOR PRECIPITATION TOWARD PA IN THE WEDNESDAY/THURSDAY TIME
FRAME AND SHOW A SECOND...POTENTIALLY STRONGER SYSTEM LATE NEXT
WEEKEND. THE TREND OF STRONGER TROUGHING MENTIONED ABOVE HAS LEAD
TO SLOWER ARRIVAL AND DEPARTURE OF THE FRONTAL SYSTEM IN THE DAILY
PROGS. THE ECMWF IN LATEST RUN HAS SLOWED UP THE PROGRESSION OF
THIS UPPER LEVEL LOW...WHERE THE GFS OPERATIONAL AND ENSEMBLES
HAVE SPED UP ITS PROGRESSION THROUGH THE GREAT LAKES REGION. A
WARM FRONT WILL BE ON THE DOORSTEP OF PA SUNDAY...AS THE EC
CONTINUES TO SLOW ITS PROGRESSION SO EXPECT THE WARM FRONT TO MOVE
IN CLOSER TO MIDDAY SUNDAY. HAVE THUS ADJUSTED POPS/TIME.
ASSOCIATED COLD FRONT DOES NOT CROSS THE STATE TIL MONDAY...WHERE
SURPRISINGLY AT THIS POINT...THE EC AND GFS COME CLOSELY IN PHASE.
THIS LARGE UPPER LEVEL LOW COULD BECOME QUASI STATIONARY OVER
SOUTHERN CANADA...GREAT LAKES REGION WHICH COULD LEAD TO A
POTENTIAL PROLONGED PERIOD OF SHOWERS AND THUNDERSTORM THROUGH THE
MIDDLE OF NEXT WEEK.
&&
.AVIATION /12Z WEDNESDAY THROUGH SUNDAY/...
23/12Z...PATCHY MVFR BR/HZ WILL IMPROVE TO VFR BY 14Z. AFTER A
QUIET START TO THE DAY...EXPECT SCT TO NMRS SHWRS AND TSTMS TO
DEVELOP THIS AFTN INTO THE EVE ALONG AND AHEAD OF A COLD FRONT
SHIFTING SEWD FROM THE GREAT LAKES. CVRG PROJECTED TO BE GREATEST
OVER THE CNTRL AND ERN PRTNS OF THE AIRSPACE WITH SOME STG TO
MARGINALLY SVR STORMS POSSIBLE. PREVAILING CONDS WILL BE VFR WITH
BRIEF MVFR- IFR VIS REDUCTIONS IN TSRA. WND SHIFT FROM SW TO NW BY
TONIGHT WITH MAIN PCPN ACTIVITY BCMG CONFINED TO SERN AREAS INTO
THU. MVFR CIGS SEEM PROBABLE OVER WRN SXNS LATE TNGT IN POST-
FRONTAL UPSLOPE NW FLOW.
OUTLOOK...
THU...SCT TSTM IMPACTS PSBL SERN AIRFIELDS AS COLD FRONT SLOWS
ALONG THE MID-ATLC COAST.
FRI...PATCHY MORNING FOG...OTHERWISE VFR/NO SIG WX.
SAT...PATCHY MORNING FOG...OTHERWISE VFR. ISOLD PM TSTM PSBL.
SUN...TSTM IMPACTS LKLY AS WARM FRONT LIFTS NWD ACRS AIRSPACE.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...LAMBERT
NEAR TERM...LAMBERT
SHORT TERM...LAMBERT
LONG TERM...LAMBERT/CERU
AVIATION...STEINBUGL
AREA FORECAST DISCUSSION
NWS GREENVILLE-SPARTANBURG SC
624 AM EDT WED JUL 23 2014
.SYNOPSIS...
WEAK HIGH PRESSURE ACROSS THE AREA TODAY WILL MOVE AWAY TONIGHT. A
SURFACE FRONT WILL APPROACH FROM THE NORTHWEST TONIGHT AND IS
EXPECTED TO MOVE ACROSS THE CAROLINAS AND NORTH GEORGIA THURSDAY
AFTERNOON AND EVENING. HIGH PRESSURE WILL BUILD IN BEHIND THE FRONT
FOR FRIDAY AND THE WEEKEND. ANOTHER FRONT IS EXPECTED TO PASS ON
MONDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 6 AM...LATEST 11U-3.9U SATELLITE IMAGES INDICATED AN EXPANDING
AREA OF LOW CLOUDS ACROSS THE PIEDMONT AND WEST TO THE SOUTHERN NC
FOOTHILLS. SFC OBSERVATIONS SHOW A WIDE RANGE OF
VISIBILITIES...RANGING FROM M1/4SM AT KMRN TO 10SM ACROSS THE
GREENVILLE/SPARTANBURG/ANDERSON AREAS. THE LOWEST VISIBILITIES ARE
GENERALLY ACROSS THE I-77 CORRIDOR AND WITHIN THE MTN VALLEYS. ALL
PREFERRED GUIDANCE INDICATES THAT THE FOG WILL DISSIPATE DURING THE
TWO HOURS FOLLOWING SUNRISE. I WILL UPDATE THE FORECAST TO ADJUST
FOG AND VISIBILITIES TO THE LATEST OBSERVATIONS AND THINKING. IN
ADDITION...LATEST MOS HAS TRENDED WARMER FOR THIS AFTERNOON...I WILL
WARM FORECAST HIGHS A CLICK. OTHERWISE...THE CURRENT FORECAST IS IN
GOOD SHAPE.
AS OF 320 AM...EARLY MORNING FOG IS EXPECTED TO DEVELOP AND EXPAND
ACROSS THE I-77 CORRDIOR AND WITHIN THE MTN VALLEYS. THE HRRR
CONDENSATION PRESSURE DEFICITS INDICATES THAT THE LOWEST VALUES
WILL EXIST ACROSS THE SOUTHEASTERN HALF OF THE CHARLOTTE METRO AREAS
AND WITHIN THE MTN VALLEYS. FOG SHOULD DISSIPATE DURING THE FIRST
TWO HOURS OF SUNLIGHT. IN ADDITION...EARLY MIXING SHOULD YIELD A
LIGHT SOUTHWEST WIND. GREATER INSOLATION AND SOUTHWEST WINDS SHOULD
RESULT IN STEADILY WARMING TEMPERATURES FROM SUNRISE TO MID
AFTERNOON. I WILL FORECAST HIGHS TO RANGE FROM THE L80S WITHIN THE
MTNS VALLEYS TO U80S TO NEAR 90 EAST OF I-85.
RECENT W/V LOOP INDICATED THAT THE MID LEVEL LOW WAS DRIFTING WEST
ACROSS THE MISSISSIPPI RIVER DELTA...AS ANOTHER TROUGH WILL DIGGING
OVER THE OHIO RIVER VALLEY. AT THE SFC...A WEAK LEE TROUGH MAY
DEVELOP ACROSS THE PIEDMONT DURING THE AFTERNOON. A COLD FRONT WILL
APPROACH FROM THE NW TODAY...REACHING THE SOUTHERN APPALACHIANS LATE
TONIGHT. CAMS INDICATE THAT SHRA AND TSRA WILL FAVOR THE MTNS AND
ADJACENT FOOTHILLS AS EARLY AS MID MORNING TODAY. COVERAGE WILL
INCREASE THROUGH THE HEAT OF THE AFTERNOON...BECOMING SCT ACROSS THE
PIEDMONT. CONVECTION SHOULD GENERALLY DISSIPATE EAST OF THE MTNS ONE
TO TWO HOURS AFTER SUNSET. HOWEVER...I WILL MAINTAIN CHC TO LIKELY
POPS ACROSS THE TN BORDER COUNTIES TO COVER THE ARRIVAL OF PRE
FRONTAL CONVECTION. LOW TEMPERATURES TONIGHT ARE FORECAST TO RANGE
FROM THE MID 60S ACROSS THE MTNS TO LOW 70S EAST.
&&
.SHORT TERM /THURSDAY THROUGH FRIDAY NIGHT/...
AS OF 230 AM EDT WEDNESDAY...THE MODEL GUIDANCE HAS COME INTO BETTER
AGREEMENT WITH THE PASSAGE OF A SURFACE FRONT MORE OR LESS DURING
PEAK HEATING ON THURSDAY. THE FRONT WILL BE DRIVEN ACROSS THE FCST
AREA BY A FAIRLY STRONG SHORT WAVE IN THE PRESENCE OF SOME UPPER
DIVERGENCE IN THE ENTRANCE REGION OF THE JET OVER THE NORTHEAST.
PLENTY OF LOW LEVEL MOISTURE WILL REMAIN AHEAD OF THE FRONT AS WELL.
THUS...WITH THE TIMING A BIT MORE IN FOCUS...FEEL IT APPROPRIATE TO
BUMP THE PRECIP PROBABILITY UP INTO THE LIKELY RANGE ACROSS THE
ENTIRE FCST AREA IN THE AFTERNOON. MIGHT BE A BIT TOO EARLY TO TALK
TOO MUCH ABOUT SEVERE WEATHER POTENTIAL...BUT THE FRONT SHOULD FOCUS
STORMS IN AN AIR MASS WITH 1500-2500 J/KG OF CAPE...SO THE DAY2
OUTLOOK SEEMS APPROPRIATE. SUSPECT WE WILL HAVE TO CONTEND WITH
SEVERAL SEVERE THUNDERSTORMS. THE FRONT WILL DROP SE DURING THE
EVENING HOURS ENDING THE PRECIP CHANCE BY THE EARLY MORNING HOURS ON
FRIDAY.
BEHIND THE FRONT...THE AIR MASS WILL NOT REALLY BE MUCH COOLER...BUT
IT SHOULD BE A BIT DRIER ON FRIDAY. HIGH PRESSURE SHOULD MOVE IN
DURING THE DAY. NOT REALLY SEEING MUCH TO SUPPORT ANY SHOWERS IN THE
AFTERNOON SO THE PRECIP CHANCES WERE LOWERED. FRIDAY NIGHT SHOULD BE
DRY AS WELL WITH SEASONAL TEMPS.
&&
.LONG TERM /SATURDAY THROUGH TUESDAY/...
AS OF 315 AM WEDNESDAY...STILL EXPECTING THE MEAN UPPER TROF OVER
THE EAST TO FILL OVER THE WEEKEND AS A SHORT WAVE RIDGE MOVES
THROUGH. THIS WILL SUPPORT WEAK HIGH PRESSURE FOR SATURDAY AND INTO
SUNDAY. THINK CONVECTION WILL BE LIMITED TO THE RIDGETOPS SATURDAY
AFTERNOON AND HAVE CUT BACK THE ALREADY MEAGER POP A BIT MORE.
EARLIER RUNS OF THE MODELS SHOWED THE POTENTIAL FOR UPSTREAM MCS
DEVELOPMENT ON SATURDAY NIGHT...AND THAT COULD STILL HAPPEN...BUT
THE MAIN FOCUS LOOKS LIKE IT WILL BE MORE LIKE THE OH VALLEY AND
CENTRAL APPALACHIANS. SO...SATURDAY NIGHT WAS KEPT DRY ACROSS THE
MOUNTAINS AS WELL. EXPECT MORE OF A RETURN TO DIURNAL THUNDERSTORMS
FOR SUNDAY. ANOTHER IN A SERIES OF FAIRLY STRONG SHORT WAVES WILL
ONCE AGAIN CARVE OUT AN UPPER TROF OVER THE EAST EARLY NEXT WEEK. IT
STILL LOOKS LIKE THIS WAVE WILL DRIVE ANOTHER COLD FRONT OVER THE
REGION ON MONDAY. UNLIKE THE EARLIER FRONT...THIS ONE SHOULD USHER
IN A NOTICEABLY DIFFERENT AIR MASS FOR NEXT TUESDAY AS A COOL
CONTINENTAL HIGH MOVES DOWN OVER THE NRN PLAINS...THEN MODIFIES AND
BUILDS IN FROM THE WEST. THAT SHOULD DROP TEMPS A CATEGORY OR MORE
BELOW NORMAL.
&&
.AVIATION /12Z WEDNESDAY THROUGH SUNDAY/...
AT KCLT...LATEST OBSERVATION INDICATE THAT THE DEWPOINT DEPRESSION
WAS AROUND ONE DEGREE. HRRR AND NAM INDICATE THAT CONDENSATION
PRESSURE DEFICITS WILL FALL ACROSS THE CLT METRO AREA TO LESS THAN 1
MB BETWEEN 9Z TO 12Z. I WILL HIGHLIGHT THE FOG POTENTIAL WITH A
TEMPO GROUP FOR MVFR FOG BETWEEN 9Z TO 12Z. SHORTLY AFTER
SUNRISE...SW WINDS SHOULD DEVELOP WITH VFR CLOUD COVER. SCT COVERAGE
OF LATE AFTERNOON TSRA ARE POSSIBLE 18Z TO 24Z.
ELSEWHERE...THE PRIMARY CONCERN FOR THE REST OF THE NIGHT WILL BE THE
DENSITY AND PLACEMENT OF FOG. KAVL WILL SEE THE GREATEST POTENTIAL
FOR VLIFR FOG AND CEILINGS. ELSEWHERE...I WILL HIGHLIGHT THE FOG
POTENTIAL WITH A TEMPO GROUP FOR MVFR FOG BETWEEN 9Z TO 12Z. SHORTLY
AFTER SUNRISE...SW WINDS SHOULD DEVELOP WITH VFR CLOUD COVER. SCT
COVERAGE OF LATE AFTERNOON TSRA ARE POSSIBLE 18Z TO 24Z
OUTLOOK... SHOWERS AND THUNDERSTORMS THURSDAY WITH THE PASSAGE OF A
COLD FRONT. SCATTERED SHOWERS AND THUNDERSTORMS MAINLY DURING THE
AFTERNOONS AND EVENINGS THROUGH THE END OF THE WEEK.
CONFIDENCE TABLE...
10-16Z 16-22Z 22-04Z 04-10Z
KCLT HIGH 83% HIGH 100% HIGH 100% HIGH 100%
KGSP HIGH 90% MED 71% HIGH 100% HIGH 100%
KAVL MED 77% HIGH 82% HIGH 100% HIGH 100%
KHKY HIGH 94% HIGH 100% HIGH 100% HIGH 100%
KGMU HIGH 95% HIGH 94% HIGH 100% HIGH 100%
KAND MED 79% HIGH 99% 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
&&
.GSP WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
NC...NONE.
SC...NONE.
&&
$$
SYNOPSIS...PM
NEAR TERM...NED
SHORT TERM...PM
LONG TERM...PM
AVIATION...NED
AREA FORECAST DISCUSSION
NWS NASHVILLE TN
1036 AM CDT WED JUL 23 2014
.UPDATE...
RADAR IMAGERY THIS MORNING SHOWS MCS MOVING SOUTHWARD ACROSS
WESTERN KY CONTINUES TO WEAKEN...BUT ADDITIONAL CONVECTION IS
FORMING ON OUTFLOW AHEAD OF THE COMPLEX. OTHER SHOWERS AND STORMS
ARE NOW DEVELOPING ACROSS THE MID STATE. LATEST HRRR RUNS SUGGEST
SCATTERED SHOWERS AND STORMS WILL BLOSSOM THROUGH NOON THEN
CONTINUE INTO THE AFTERNOON BEFORE DIMINISHING...WITH ADDITIONAL
ACTIVITY DEVELOPING THIS EVENING. HOWEVER...EARLIER RUNS HAD
DIFFERENT SOLUTIONS...LEADING TO LOW CONFIDENCE IN EVENTUAL
COVERAGE AND PLACEMENT OF STORMS. NEVERTHELESS...WILL BEGIN HIGH
CHANCE POPS NOW AND CONTINUE THROUGH THE AFTERNOON. CANNOT RULE
OUT SOME STRONGER STORMS MAINLY THIS AFTERNOON WITH LI VALUES NEAR
-6 AND CONSIDERABLE DRY AIR NOTED ALOFT ON 12Z OHX SOUNDING...BUT
NOT ANTICIPATING ANY WIDESPREAD STRONG OR SEVERE ACTIVITY. OTHER
ADJUSTMENTS WERE MADE TO GRIDS BASED ON LATEST OBS...BUT REST OF
FORECAST IS ESSENTIALLY UNCHANGED.
SHAMBURGER
&&
.PREV DISCUSSION... /ISSUED 738 AM CDT WED JUL 23 2014/
UPDATE...FOR 12Z TAFS
AVIATION...
A FRONTAL BOUNDARY WILL MOVE INTO MIDDLE TN FROM THE NW LATER TODAY
BRINGING THUNDERSTORMS AND SHOWERS. SOME STRONG STORMS WILL BE
POSSIBLE. INTRODUCED VICINITY STORMS AT CKV AROUND 18Z. WILL HAVE
TO SEE HOW CONVECTION MOVING INTO WESTERN KENTUCKY TRACKS THIS
MORNING TO INCLUDE SOMETHING MORE THAN VICINITY. LATEST HRRR IS
FORECASTING REDEVELOPMENT OF A LINE OF STORMS LATER THIS MORNING
THAT FALLS APART BEFORE IMPACTING NW MIDDLE TN. REGARDLESS IF THAT
LINE DOES FALL APART CONDITIONS WILL BE FAVORABLE FOR SCATTERED
THUNDERSTORMS BY 22Z FOR BNA AND CSV. WINDS WILL SHIFT TO BE OUT
OF THE NW AROUND 00Z TODAY FOR CKV AND BNA...AROUND 02Z FOR CSV.
SOME LIGHT SHOWERS MAY LINGER OVERNIGHT TONIGHT WITH CIGS FALLING
TO 3KFT OR LESS BY MIDNIGHT AND DECREASING VIS FOR CKV AND BNA.
PREV DISCUSSION... /ISSUED 344 AM CDT WED JUL 23 2014/
DISCUSSION...
UPPER LOW IS LOCATED NEAR NEW ORLEANS THIS MORNING WITH AN
INVERTED TROUGH AXIS EXTENDING NORTHEASTWARD ACROSS EASTERN TN.
MEANWHILE...SFC BOUNDARY EXTENDS FROM LAKE ERIE SW THROUGH MO.
NORTHWESTERLY FLOW ALOFT TO BECOME MORE ENHANCED AS WE MOVE
THROUGH TODAY. THIS WILL ALLOW THIS FRONTAL BOUNDARY TO MOVE OUR
WAY AND MOVE ACROSS THE AREA TONIGHT. 18Z AND 00Z DEPICTIONS OF
THE UPPER LEVEL FLOW REVEAL A DIVERGING FLOW ALOFT AND THIS WILL
COUPLE WITH ELEVATED LEVELS OF CURVATURE AND SHEAR JUST TO THE
NORTHWEST OF THE DIVERGING FLOW. LATEST HRRR IN SUPPORT OF LATE
MORNING TO EARLY AFTERNOON CONVECTIVE DEVELOPMENT ACROSS OUR
SOUTHEAST WHICH IS IN CLOSER PROXIMITY TO THE INVERTED TROUGH.
THEN...BY MID AND LATE AFTERNOON...THE APPROACHING FRONTAL
BOUNDARY WILL KICK OFF SOME CONVECTION ACROSS THE NORTHWEST HALF
OF MIDDLE TN. ALL IN ALL...POPS OF 30-50 PERCENT LOOKS REASONABLE
FOR TODAY. CAPES WILL REACH 2000 J/KG BY LATE AFTERNOON SO CANNOT
RULE OUT SOME STRONG STORMS THIS AFTERNOON AND EVENING AS WELL.
SO...AGAIN TONIGHT...A GOOD CHANCE OF SHOWERS AND TSTMS WILL BE IN
THE FORECAST AS THE FROPA OCCURS AND PVA WORKS ACROSS OUR AREA.
THE FRONTAL BOUNDARY WILL BE A SLOW MOVER. THUS...LOW POPS WILL BE
INCLUDED FOR THURSDAY AS WELL.
FOR THE NEAR TERM TEMPS...ANOTHER WARM TO HOT DAY TODAY AS THE FRONT
PRESSES DOWN SLOWLY FROM THE NORTH. NOT NEARLY AS HOT ON THURSDAY AS
THE REPLACING AIRMASS FEATURES A REASONABLY IMPRESSIVE THERMAL
TROUGH FOR THIS TIME OF YEAR. THURSDAY LOOKS LIKE HIGHS IN THE
LOWER TO MID 80S WITH DEWPOINTS IN THE LOWER 60S. LOWER 60S FOR
LOWS ARE EXPECTED THU NT.
IN THE EXT FCST...UPPER TROUGHING WILL PULL EAST AS RIDGING ATTEMPTS
TO EXPAND EASTWARD FROM THE SOUTHWESTERN U.S.. NORTHWEST FLOW WILL
BE WEAKER BUT JUST STRONG ENOUGH TO ALLOW ANOTHER COLD FRONT TO MOVE
OUR WAY THIS WEEKEND. AS THE FRONT REACHES THE MID STATE ON SUNDAY
NIGHT...UPPER TROUGHING OVER THE EASTERN U.S. IS EXPECTED TO
AMPLIFY. LOOKS LIKE WE COULD SEE SOME APPRECIABLE RAINFALL FOR
SUNDAY AND SUNDAY NIGHT. INSTABILITY PARAMETERS ON SUNDAY AFTERNOON
ARE RATHER IMPRESSIVE SO ANOTHER ROUND OF STRONG STORMS LOOKS
POSSIBLE.
A FAIRLY POTENT SFC HIGH FOR LATE JULY WILL THEN BUILD IN FROM THE
NORTH. THERMAL TROUGHING LOOKS IMPRESSIVE WITH 850 MB TEMPS OF
AROUND 12C. HIGH TEMPS IN THE LOWER TO MID 80S WITH LOW RELATIVE
HUMIDITY IS EXPECTED MON THROUGH WED OF NEXT WEEK. WILL BE
UNDERCUTTING THE MEX NUMBERS AS THE EURO SOLUTION IS EVEN STRONGER
WITH THE THERMAL TROUGHING.
&&
.OHX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
55
AREA FORECAST DISCUSSION
NWS NASHVILLE TN
738 AM CDT WED JUL 23 2014
.UPDATE...FOR 12Z TAFS
&&
.AVIATION...
A FRONTAL BOUNDARY WILL MOVE INTO MIDDLE TN FROM THE NW LATER TODAY
BRINGING THUNDERSTORMS AND SHOWERS. SOME STRONG STORMS WILL BE
POSSIBLE. INTRODUCED VICINITY STORMS AT CKV AROUND 18Z. WILL HAVE
TO SEE HOW CONVECTION MOVING INTO WESTERN KENTUCKY TRACKS THIS
MORNING TO INCLUDE SOMETHING MORE THAN VICINITY. LATEST HRRR IS
FORECASTING REDEVELOPMENT OF A LINE OF STORMS LATER THIS MORNING
THAT FALLS APART BEFORE IMPACTING NW MIDDLE TN. REGARDLESS IF THAT
LINE DOES FALL APART CONDITIONS WILL BE FAVORABLE FOR SCATTERED
THUNDERSTORMS BY 22Z FOR BNA AND CSV. WINDS WILL SHIFT TO BE OUT
OF THE NW AROUND 00Z TODAY FOR CKV AND BNA...AROUND 02Z FOR CSV.
SOME LIGHT SHOWERS MAY LINGER OVERNIGHT TONIGHT WITH CIGS FALLING
TO 3KFT OR LESS BY MIDNIGHT AND DECREASING VIS FOR CKV AND BNA.
&&
.PREV DISCUSSION... /ISSUED 344 AM CDT WED JUL 23 2014/
DISCUSSION...
UPPER LOW IS LOCATED NEAR NEW ORLEANS THIS MORNING WITH AN
INVERTED TROUGH AXIS EXTENDING NORTHEASTWARD ACROSS EASTERN TN.
MEANWHILE...SFC BOUNDARY EXTENDS FROM LAKE ERIE SW THROUGH MO.
NORTHWESTERLY FLOW ALOFT TO BECOME MORE ENHANCED AS WE MOVE
THROUGH TODAY. THIS WILL ALLOW THIS FRONTAL BOUNDARY TO MOVE OUR
WAY AND MOVE ACROSS THE AREA TONIGHT. 18Z AND 00Z DEPICTIONS OF
THE UPPER LEVEL FLOW REVEAL A DIVERGING FLOW ALOFT AND THIS WILL
COUPLE WITH ELEVATED LEVELS OF CURVATURE AND SHEAR JUST TO THE
NORTHWEST OF THE DIVERGING FLOW. LATEST HRRR IN SUPPORT OF LATE
MORNING TO EARLY AFTERNOON CONVECTIVE DEVELOPMENT ACROSS OUR
SOUTHEAST WHICH IS IN CLOSER PROXIMITY TO THE INVERTED TROUGH.
THEN...BY MID AND LATE AFTERNOON...THE APPROACHING FRONTAL
BOUNDARY WILL KICK OFF SOME CONVECTION ACROSS THE NORTHWEST HALF
OF MIDDLE TN. ALL IN ALL...POPS OF 30-50 PERCENT LOOKS REASONABLE
FOR TODAY. CAPES WILL REACH 2000 J/KG BY LATE AFTERNOON SO CANNOT
RULE OUT SOME STRONG STORMS THIS AFTERNOON AND EVENING AS WELL.
SO...AGAIN TONIGHT...A GOOD CHANCE OF SHOWERS AND TSTMS WILL BE IN
THE FORECAST AS THE FROPA OCCURS AND PVA WORKS ACROSS OUR AREA.
THE FRONTAL BOUNDARY WILL BE A SLOW MOVER. THUS...LOW POPS WILL BE
INCLUDED FOR THURSDAY AS WELL.
FOR THE NEAR TERM TEMPS...ANOTHER WARM TO HOT DAY TODAY AS THE FRONT
PRESSES DOWN SLOWLY FROM THE NORTH. NOT NEARLY AS HOT ON THURSDAY AS
THE REPLACING AIRMASS FEATURES A REASONABLY IMPRESSIVE THERMAL
TROUGH FOR THIS TIME OF YEAR. THURSDAY LOOKS LIKE HIGHS IN THE
LOWER TO MID 80S WITH DEWPOINTS IN THE LOWER 60S. LOWER 60S FOR
LOWS ARE EXPECTED THU NT.
IN THE EXT FCST...UPPER TROUGHING WILL PULL EAST AS RIDGING ATTEMPTS
TO EXPAND EASTWARD FROM THE SOUTHWESTERN U.S.. NORTHWEST FLOW WILL
BE WEAKER BUT JUST STRONG ENOUGH TO ALLOW ANOTHER COLD FRONT TO MOVE
OUR WAY THIS WEEKEND. AS THE FRONT REACHES THE MID STATE ON SUNDAY
NIGHT...UPPER TROUGHING OVER THE EASTERN U.S. IS EXPECTED TO
AMPLIFY. LOOKS LIKE WE COULD SEE SOME APPRECIABLE RAINFALL FOR
SUNDAY AND SUNDAY NIGHT. INSTABILITY PARAMETERS ON SUNDAY AFTERNOON
ARE RATHER IMPRESSIVE SO ANOTHER ROUND OF STRONG STORMS LOOKS
POSSIBLE.
A FAIRLY POTENT SFC HIGH FOR LATE JULY WILL THEN BUILD IN FROM THE
NORTH. THERMAL TROUGHING LOOKS IMPRESSIVE WITH 850 MB TEMPS OF
AROUND 12C. HIGH TEMPS IN THE LOWER TO MID 80S WITH LOW RELATIVE
HUMIDITY IS EXPECTED MON THROUGH WED OF NEXT WEEK. WILL BE
UNDERCUTTING THE MEX NUMBERS AS THE EURO SOLUTION IS EVEN STRONGER
WITH THE THERMAL TROUGHING.
&&
.OHX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
11
AREA FORECAST DISCUSSION
NWS CHEYENNE WY
912 AM MDT WED JUL 23 2014
.UPDATE...
ISSUED AT 850 AM MDT WED JUL 23 2014
EAST UPSLOPE FLOW IS CURRENTLY HOLDING THE LOW CLOUDS IN PLACE
ACROSS MUCH OF SOUTHEAST WYOMING EAST OF THE LARAMIE RANGE AND
INTO PARTS OF THE NEBRASKA PANHANDLE. LOW CLOUDS SHOULD MIX OUT BY
LATE THIS MORNING. NOT EXPECTING A BIG IMPACT ON HIGH TEMPERATURES
OR CHANCES FOR THUNDERSTORMS TODAY. ISOLATED CONVECTION
TO DEVELOP OVER THE MOUNTAINS BY EARLY THIS AFTERNOON. LOW CLOUDS
AND STABLE MID LEVEL AIR LEFT BEHIND FORM LAST NIGHTS
THUNDERSTORMS WILL INITIALLY INHIBIT EASTWARD MOVEMENT OF
THUNDERSTORMS INTO THE PLAINS. ONE THING OF NOTE IS THE STABLE
LAYER THAT IS IN PLACE MAY BE STRONGER THAN MODELS SUGGEST...WHICH
COULD HAVE A BROADER IMPACT ON DECREASING THUNDERSTORM CHANCES.
AT THIS TIME IS APPEARS THE MAIN CHANCES FOR THUNDERSTORMS IN THE
PLAINS WILL BE LATE THIS AFTERNOON AND EVENING WITH THE GREATEST
THREAT INTO EAST CENTRAL WYOMING AND THE NORTHERN NEBRASKA
PANHANDLE. THIS IS ALSO WHERE THE MAIN THREAT FOR SEVERE
THUNDERSTORMS WILL BE GIVEN A STRONGER SHEAR PROFILE AND HIGHER
CAPE VALUES. MAIN THREAT WILL BE THE LARGE HAIL BUT STRONG WINDS
AND AN AN ISOLATED TORNADO POSSIBLE. WITH ANY LUCK MOST
THUNDERSTORM ACTIVITY IN THE PLAINS WILL HOLD OFF UNTIL LATE THIS
EVENING AS THE LOW LEVEL JET RAMPS UP AND STRONGER MID LEVEL
THETAE ADVECTION KICKS IN. THIS WILL MAKE FOR THE MAIN THUNDERSTORM
CHANCES TOWARD CHADRON AND POINTS NORTH AND EAST OF THE FORECAST AREA.
&&
.SHORT TERM...(TODAY THROUGH FRIDAY)
ISSUED AT 300 AM MDT WED JUL 23 2014
LOTS OF FORECAST CHALLENGES WITH THIS FORECAST PACKAGE...RANGING
FROM SEVERE CONVECTIVE WEATHER TODAY TO FIRE WEATHER CONCERNS
THURSDAY AND FRIDAY.
CURRENTLY...THE MUCH ANTICIPATED COLD FRONT DID MOVE INTO THE AREA
LAST EVENING AND IS CURRENTLY LOCATED GENERALLY ALONG A LINE FROM
CASPER...ALONG THE LARAMIE RANGE DOWN TO LARAMIE AND THEN INTO
NORTHEASTERN COLORADO. THIS FRONT IS SEPARATING VERY MOIST AIR
EAST OF THE FRONT...CHEYENNE HAS A 1AM DEWPOINT OF 57F/LARAMIE
55F...FROM VERY DRY AIR OUT OVER CARBON COUNTY WHERE THE DEWPOINT
AT RAWLINS IS 29F. THIS FEATURE IS GOING TO PLAY A MAJOR ROLE IN
TODAYS FORECAST WEATHER.
FOR TODAY...FRONT IS GOING TO REMAIN AT ITS CURRENT LOCATION
THROUGH THE MORNING HOURS BEFORE IT STARTS TO GET FORCED EAST WITH
INCREASING WESTERLY FLOW. LATEST HRRR FORECAST COMPOSITE
REFLECTIVITY HAS CONVECTION INITIATING ACROSS ALBANY COUNTY AND
THE SOUTH LARAMIE RANGE RIGHT AROUND 20Z TODAY DURING PEAK
HEATING. NAM SOUNDING FOR CHEYENNE HAS CAPE AROUND 1300 J/KG AT
THAT TIME WITH NO CONVECTIVE INHIBITION. PANHANDLE STAYS CAPPED A
LITTLE LONGER...NOT BREAKING THE CAP UNTIL AFTER 00Z. MUCH MORE
UNSTABLE OUT THERE WITH CHADRON NAM SOUNDING SHOWING SBCAPE CLOSE
TO 3500 J/KG. THINK DAY 1 SPC SLIGHT RISK AREA IS PRETTY
GOOD...BUT DO THINK THE LARAMIE COUNTY IS GOING TO SEE SOME SEVERE
THUNDERSTORMS AS WELL AND HAVE TAILORED OUR FORECAST WITH LARAMIE
COUNTY EXPERIENCING SEVERE THUNDERSTORMS THIS AFTERNOON. SEVERE
THUNDERSTORMS INITIALLY OVER THE SOUTHEAST WYOMING PLAINS...THEN
SPREADING EAST INTO THE PANHANDLE AFTER 00Z...AS THE FRONT MOVES
EAST AS A DRY LINE.
FOR THURSDAY...UPPER LOW MOVES INTO MONTANA THURSDAY AFTERNOON
WITH 700MB WINDS INCREASING OVER WYOMING. BY 18Z GFS 700MB WINDS
INCREASE TO 25-30KTS OVER CARBON AND ALBANY COUNTIES. BOTH THE GFS
AND ECMWF SHOW A UPPER LEVEL SHORTWAVE TRACKING THROUGH THE UPPER
RIDGE ALONG THE COLORADO/WYOMING LINE THAT WILL INTERACT WITH SOME
RESIDUAL MONSOONAL MOISTURE TO CREATE AFTERNOON THUNDERSTORMS. GFS
HAS PRECIP MAINLY OVER COLORADO...WHILE ECMWF SPREAD THIS MOISTURE
NORTH INTO WYOMING. DID A BLEND OF THE TWO MODELS WITH CHANCE
SHOWERS AND THUNDERSTORMS OVER SOUTHERN WYOMING NEAR THE COLORADO
BORDER, FORECAST SOUNDING SHOW THE POSSIBILITY OF DRY
THUNDERSTORMS OUT WEST OF THE LARAMIE RANGE THAT HAS ME A LITTLE
WORRIED ABOUT FIRE STARTS AS AFTERNOON MIN HUMIDITIES FALL TO 10
PERCENT ACROSS CARBON...NORTH ALBANY AND WEST CONVERSE COUNTIES.
WENT AHEAD WITH A FIRE WEATHER WATCH FOR THURSDAY FOR CONVERSE
COUNTY AS THIS AREA LOOKS TO BE THE BEST FOR A COMBINATION OF LOW
HUMIDITIES...GUSTY WINDS AND DRY THUNDERSTORMS.
GUSTY WEST WINDS CONTINUE INTO FRIDAY WITH VERY DRY DOWNSLOPING
WINDS OFF THE LARAMIE RANGE. COULD BE LOOKING AT WIDESPREAD FIRE
WEATHER CONDITIONS FRIDAY.
.LONG TERM...(FRIDAY NIGHT THROUGH TUESDAY)
ISSUED AT 240 AM MDT WED JUL 23 2014
MODELS GENERALLY IN GOOD AGREEMENT THROUGH THE WEEKEND WITH THE
OVERALL PATTERN...SHOWING A POTENT UPPER LEVEL TROUGH DIGGING
SOUTHWARD OUT OF CANADA AND INTO THE GREAT LAKES REGION BY EARLY
SUNDAY. THIS WILL RESULT IN NORTHWEST FLOW OVER THE FORECAST AREA
AS THE STRONG UPPER LEVEL HIGH NUDGES SOUTHWARD AND THE
ASSOCIATED RIDGE AXIS WILL EXTEND NORTHWEST INTO THE GREAT BASIN
REGION. THERE ARE STILL DISCREPANCIES BETWEEN MODELS REGARDING
AVAILABLE LOW TO MIDLEVEL MOISTURE THROUGH THE WEEKEND AND INTO
EARLY NEXT WEEK. ALTHOUGH A SERIES OF COOL FRONTS ARE EXPECTED TO
PUSH SOUTHWARD ACROSS THE FORECAST AREA BEGINNING FRIDAY
NIGHT...THE LACK OF ANY DEFINED DISTURBANCES IS CREATING QUITE A
BIT OF UNCERTAINTY WITH TSTORM CHANCES INTO MONDAY. CURRENT 00Z
MODELS ARE BEGINNING TO TREND DRIER...AS THE NORTHWEST FLOW
RESULTS IN A BIT MORE STABILITY THAN PREVIOUSLY EXPECTED...NUDGING
THE MONSOON MOISTURE FURTHER SOUTH INTO THE FOUR CORNERS REGION
AND COLORADO. STARTED TO LOWER POP FOR THIS WEEKEND ACROSS MOST OF
THE AREA...ESPECIALLY FURTHER NORTH SINCE THE ECMWF IS NOW
TRENDING DRIER AS WELL. CURRENT SOUNDINGS SHOW TOO MUCH DRY AIR
ALOFT...SUPPRESSING ANY CONVECTION THAT DOES FORM. AFTER ANOTHER
WARM DAY ON SATURDAY...EXPECT TEMPERATURES TO LOWER BELOW NORMAL
ON SUNDAY WITH HIGHS IN THE 70S TO MID 80S UNDER COOL EAST TO
NORTHEAST FLOW.
CONDITIONS BECOME A LITTLE MORE INTERESTING AFTER MONDAY AS BOTH
THE GFS AND ECMWF SHOW SHORTWAVE ENERGY MOVING CLOCKWISE AROUND
THE MAIN UPPER LEVEL HIGH AND INTO WYOMING. INCREASED POP LATE MONDAY
THROUGH WEDNESDAY...MAINLY IN THE AFTERNOON AND EVENINGS. BOTH THE
GFS AND ECMWF ARE ON THE AGGRESSIVE SIDE WITH A HIGHER COVERAGE OF
SHOWERS AND TSTORMS...AT LEAST SCATTERED DURING THE AFTERNOON...AS
THE SHORTWAVE ENERGY PUSHES ACROSS EASTERN WYOMING BY WEDNESDAY.
KEPT TEMPERATURES A FEW DEGREES BELOW NORMAL DUE TO EASTERLY
UPSLOPE FLOW AND 700MB TEMPERATURES LOWERING TO BELOW 10C.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH WEDNESDAY NIGHT)
VFR CONDITIONS WILL PREVAIL THROUGH WEDNESDAY NIGHT...ALTHOUGH
BRIEF MVFR VIS ARE POSSIBLE IN AND AROUND THUNDERSTORM ACTIVITY
THIS AFTERNOON AND THIS EVENING. ANOTHER ROUND OF SHOWERS AND
THUNDERSTORMS WILL AFFECT THE HIGH PLAINS IN ADDITION TO KLAR
BEGINNING EARLY THIS AFTERNOON. THERE IS A SLIGHT CHANCE OF LOW
CIGS EARLY THIS MORNING ACROSS PARTS OF THE HIGH PLAINS...BUT
THERE IS STILL TOO MUCH UNCERTAINTY AT THIS TIME TO ADD TO AREA
TAFS.
&&
.FIRE WEATHER...
ISSUED AT 300 AM MDT WED JUL 23 2014
DRY CONDITIONS ACROSS WESTERN CARBON COUNTY AGAIN TODAY. A COLD
FRONT GENERALLY ALONG A LINE FROM CASPER TO LARAMIE WILL SEPARATE
RELATIVELY MOIST AIR EAST OF THE FRONT FROM THE REALLY DRY AIR TO
THE WEST. WETTING RAINS ARE LIKELY IN THE EASTERN SECTOR TODAY AND
TONIGHT WITH EXCELLENT OVERNIGHT RH RECOVERIES. CONDITIONS CHANGE
FOR THURSDAY THOUGH AS THE FRONT BEGINS TO MOVE EAST AGAIN AND
WINDS BEGIN TO PICK UP WEST OF THE LARAMIE RANGE. CRITICAL FIRE
WEATHER CONDITIONS FROM GUSTY WINDS AND LOW HUMIDITIES EARLY
THURSDAY AFTERNOON. TO COMPLICATE THE CONDITIONS MORE...WE HAVE
THE POSSIBILITY OF DRY THUNDERSTORMS WEST OF THE LARAMIE RANGE
THAT COULD CREATE SOME FIRE STARTS THURSDAY AFTERNOON. A FIRE
WEATHER WATCH HAS BEEN ISSUED FOR FWZ 301 FOR THURSDAY LATE
MORNING THROUGH THE AFTERNOON. DRY AND WINDY CONDITIONS TO
CONTINUE INTO SATURDAY FOR MORE WIDESPREAD FIRE WEATHER CONDITIONS
ACROSS SOUTHEAST WYOMING.
&&
.CYS WATCHES/WARNINGS/ADVISORIES...
WY...FIRE WEATHER WATCH FROM THURSDAY MORNING THROUGH THURSDAY
AFTERNOON FOR WYZ301.
NE...NONE.
&&
$$
UPDATE...SML
SHORT TERM...CLAYCOMB
LONG TERM...TJT
AVIATION...TJT
FIRE WEATHER...CLAYCOMB
AREA FORECAST DISCUSSION
NWS TUCSON AZ
235 PM MST WED JUL 23 2014
.SYNOPSIS...ENOUGH MOISTURE IS BACK IN PLACE FOR A CHANCE OF SHOWERS
AND THUNDERSTORMS THIS AFTERNOON. HOTTER TEMPERATURES ARE POSSIBLE
AGAIN TODAY AND THURSDAY. THUNDERSTORMS ARE EXPECTED TO INCREASE
THIS WEEKEND... ESPECIALLY SATURDAY AFTERNOON AND SATURDAY NIGHT.
&&
.DISCUSSION...STORMS ARE CURRENTLY FORMING ACROSS CENTRAL PIMA
COUNTY AND ACROSS THE RIM. STORM MOTION IS PITIFUL THOUGH...WITH
MAYBE 10 MPH OF WESTERLY MOTION WITH THE FASTER MOVING STORMS. GIVEN
THE DECENT PRECIP WATER VALUES...I AM CONCERNED FOR ISOLATED FLOOD
THREAT. LATEST HRRR SEEMS TO HAVE THE BEST HANDLE ON THE CONVECTION
THUS FAR AND HINTS AT CONVECTION FOCUSED MAINLY ACROSS THE CENTRAL
PORTION OF OUR AREA...OR NEAR THE I-10 CORRIDOR. COULD SEE SOME
MARGINALLY SEVERE STORMS TODAY. BUT THE TALL SKINNY CAPE
PROFILE...ALSO NOTED WITH THE .05 NORMALIZED CAPE VALUE...SUGGEST
LIMITED PARCEL ACCELERATION TODAY SO IT MAY BE DIFFICULT TO SUSTAIN
STRONG A LASTING UPDRAFTS.
I INCREASED TOMORROWS MIN TEMPERATURES IN THE VALLEYS BY A FEW
DEGREES BASED ON MIN TEMPS FROM THIS MORNING. THE NEAR RECORD WARM
LOWS ARE AGAIN POSSIBLE UNLESS CONVECTIVE OUTFLOWS PROVIDE LOCALIZED
COOLING. THE UPPER RIDGE AGAIN DROPS SOUTH TOMORROW AND THE MODELS
RESPOND BY DECREASING THE MID LEVEL MOISTURE. SO CONVECTIVE ACTIVITY
SHOULD BE DOWN...BUT THE TEMPS WILL BE UP AGAIN. MOISTURE SLOWLY
RETURNS FRIDAY AND AN INVERTED TROUGH SHOULD MOVE ACROSS THE AREA
SATURDAY. SO WE CURRENTLY FOCUS THE HIGHEST POPS OVER THE NEXT 7
DAYS ON SATURDAY THINKING THE ADDED LIFT FROM THE INVERTED TROUGH
WILL BE ENOUGH TO OVERCOME THE MARGINAL MOISTURE CONTENT. MOISTURE
CONTENT STARTS TO DISSIPATE SUNDAY BEFORE A MORE PRONOUNCED DRYING
TREND BEGINS MONDAY.
NEXT WEEK...THE LONG WAVE PATTERN SHOWS A HIGH AMPLITUDE RIDGE OVER
THE WEST WITH A DEEP TROUGH OVER THE EAST. THIS TYPE OF BLOCKING
PATTERN CAN GREATLY REDUCE THE PRECIP CHANCES AND PROMOTE WARMER
THAN NORMAL CONDITIONS. CERTAINLY CAN NOT RULE OUT SOME ISOLATED
STORMS NEXT WEEK...BUT I`M MORE CONCERNED FOR THE EXCESSIVE HEAT
POTENTIAL. CURRENT GUIDANCE IS SHOWING SIMILAR TEMPS AS WE
EXPERIENCED THIS WEEK...BUT 850-700MB THICKNESS VALUES SUGGEST WE
MAY BE A FEW DEGREES TOO COOL FOR MAX TEMPS NEXT WEEK.
JJB
&&
.AVIATION...VALID THRU 24/18Z.
FAIR AMOUNT OF CLEARING HAS OCCURRED THIS MORNING WHICH HAS ALLOW
FOR SOME GOOD MIXING. THE GOOD THING IS THERE ISN`T MUCH WIND IN THE
LOW/MID LEVELS TO TAP INTO. THIS SHOULD KEEP MOST OF THE GUST WELL
BELOW 20KTS. THE ONE CAVEAT TO THAT WILL BE GIVEN THE INVERTED V
PROFILE SEEN IN POINT SOUNDINGS FROM ACROSS THE AREA ALL TERMINALS
WILL HAVE THE POTENTIAL FOR GUSTY OUTFLOW WINDS WITH THE CONVECTION.
ENOUGH INSTABILITY EXIST OVER THE AREA FOR CONVECTION THOUGH THERE
ISN/T MUCH IN THE HAIL GROWTH ZONE WHICH WILL LIMIT LIGHTNING
ACTIVITY. THAT BEING SAID...ONCE STORMS DEVELOP AND MODIFY THE
ENVIRONMENT THIS WILL LIKELY CHANGE QUICKLY. HOWEVER...GIVEN THE LOW
CONFIDENCE IN WHERE STORMS WILL DEVELOP AT THIS TIME WILL KEEP TS
OUT OF ALL TERMINALS AND WILL HANDLE WITH AMD ONCE DEVELOPMENT
OCCURS. AVIATION DISCUSSION NOT UPDATED FOR TAF AMENDMENTS.
&&
.FIRE WEATHER...MOISTURE HAS RETURNED TO SOUTHEAST ARIZONA WITH
SCATTERED MAINLY AFTERNOON AND EVENING SHOWERS AND THUNDERSTORMS
ACROSS MOST OF SOUTHEAST ARIZONA. THERE WILL BE A BRIEF DOWNTURN IN
STORM COVERAGE THURSDAY BEFORE A MORE TYPICAL MONSOON PATTERN MOVES
IN BY THIS WEEKEND. EXPECT STRONG...GUSTY AND ERRATIC WINDS WITH THE
STRONGER THUNDERSTORMS. POTENTIALLY HOTTER TEMPERATURES WEDNESDAY
AND THURSDAY WITH STRONG HIGH PRESSURE NEARBY...BUT WITH THIS WILL
BE MITIGATED SOMEWHAT BY THE MOISTURE BACK IN THE PICTURE.
&&
.TWC WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
VISIT US ON FACEBOOK...TWITTER...YOUTUBE...AND AT WEATHER.GOV/TUCSON
AREA FORECAST DISCUSSION
NWS TUCSON AZ
955 AM MST WED JUL 23 2014
.SYNOPSIS...ENOUGH MOISTURE IS BACK IN PLACE FOR A CHANCE OF SHOWERS
AND THUNDERSTORMS. HOTTER TEMPERATURES ARE POSSIBLE AGAIN TODAY AND
THURSDAY. THUNDERSTORMS ARE EXPECTED TO INCREASE THIS WEEKEND...
ESPECIALLY SATURDAY AFTERNOON AND SATURDAY NIGHT.
&&
.UPDATE...AVIATION DISCUSSION UPDATED BELOW.
&&
.DISCUSSION...A LITTLE MORE CONFIDENT IN STORM DEVELOPMENT TODAY
THAN WE HAVE EXPERIENCE RECENTLY. SOUTHEAST LOW LEVEL WINDS BASED ON
THE 12Z SOUNDING HELPED IMPROVE OUR MOISTURE CONTENT. PRECIP WATER
VALUE HIT 1.59...WHICH MATCHES THE SATELLITE DERIVED PRECIP WATER
FIELDS WITH THE 1.50 INCH VALUES ACROSS MUCH OF S.E. AZ. SOUNDING
ALSO SHOWED MORE INSTABILITY IN PLACE THAN RECENT DAYS...AND WITH
ABUNDANT SUNSHINE SO FAR TODAY AND EXPECTED HIGH TEMPS A FEW DEGREES
ABOVE CLIMO...WE ARE IN GOOD SHAPE TO REALIZE THAT POTENTIAL. THERE
WERE ALSO A FEW MCS EVENTS OVERNIGHT ACROSS NORTHERN MEXICO WHICH
LIKELY CONTRIBUTED TO OUR MOISTURE INCREASE TODAY.
HI RESOLUTION MODELS...HRRR AND WRF VARIANTS...HAVE A FEW
CONSISTENCIES FOR TODAY. THE CONSISTENCIES WOULD POINT TO THE BEST
SHOT FOR STORMS DEVELOPING IN THE 18 TO 20Z RANGE OVER THE EASTERN
ZONES...THEN SPREAD WEST INTO PIMA COUNTY DUE TO THE BETTER LL
EASTERLY MEAN FLOW STARTING AROUND 22 OR 23Z. CERTAINLY SOME
POTENTIAL FOR A STRONG WIND GUST OR TWO. IN FACT...OUR LOCAL WRF RUN
AND THE UOFA WRF BOTH HINT AT STRONG OUTFLOW IMPACTING PINAL COUNTY
TODAY. THAT MAKES ME A LITTLE NERVOUS FOR BLOWING DUST...BUT GIVEN
THAT THE HRRR IS NOT SHOWING THE OUTFLOW AT ALL...I PLAN TO PLAY THE
WAIT AND SEE GAME TODAY AND HOLD OFF ON ISSUING ANY DUST ADVISORIES.
FINGERS WILL BE ON THE TRIGGER THOUGH IF RADAR TRENDS SUPPORT THE
WRF RUNS. EITHER WAY...BE AWARE OF THE BLOWING DUST POTENTIAL ACROSS
PINAL COUNTY TODAY.
JJB
&&
.AVIATION...VALID THRU 24/18Z.
FAIR AMOUNT OF CLEARING HAS OCCURRED THIS MORNING WHICH HAS ALLOW
FOR SOME GOOD MIXING. THE GOOD THING IS THERE ISN`T MUCH WIND IN THE
LOW/MID LEVELS TO TAP INTO. THIS SHOULD KEEP MOST OF THE GUST WELL
BELOW 20KTS. THE ONE CAVEAT TO THAT WILL BE GIVEN THE INVERTED V
PROFILE SEEN IN POINT SOUNDINGS FROM ACROSS THE AREA ALL TERMINALS
WILL HAVE THE POTENTIAL FOR GUSTY OUTFLOW WINDS WITH THE CONVECTION.
ENOUGH INSTABILITY EXIST OVER THE AREA FOR CONVECTION THOUGH THERE
ISN/T MUCH IN THE HAIL GROWTH ZONE WHICH WILL LIMIT LIGHTNING
ACTIVITY. THAT BEING SAID...ONCE STORMS DEVELOP AND MODIFY THE
ENVIRONMENT THIS WILL LIKELY CHANGE QUICKLY. HOWEVER...GIVEN THE LOW
CONFIDENCE IN WHERE STORMS WILL DEVELOP AT THIS TIME WILL KEEP TS
OUT OF ALL TERMINALS AND WILL HANDLE WITH AMD ONCE DEVELOPMENT
OCCURS. AVIATION DISCUSSION NOT UPDATED FOR TAF AMENDMENTS.
&&
.FIRE WEATHER...MOISTURE HAS RETURNED TO SOUTHEAST ARIZONA TODAY
WITH SCATTERED MAINLY AFTERNOON AND EVENING SHOWERS AND
THUNDERSTORMS ACROSS MOST OF SOUTHEAST ARIZONA TODAY. THERE WILL BE
A BRIEF DOWNTURN IN STORM COVERAGE THURSDAY BEFORE A MORE TYPICAL
MONSOON PATTERN MOVES IN BY THIS WEEKEND. EXPECT STRONG...GUSTY AND
ERRATIC WINDS WITH THE STRONGER THUNDERSTORMS. POTENTIALLY HOTTER
TEMPERATURES WEDNESDAY AND THURSDAY WITH STRONG HIGH PRESSURE
NEARBY...BUT WITH THIS WILL BE MITIGATED SOMEWHAT BY THE MOISTURE
BACK IN THE PICTURE.
&&
.PREV DISCUSSION...MOISTURE HAD FINALLY RETURNED TO SOUTHEAST
ARIZONA AS DEWPOINT TEMPERATURES WERE RUNNING AROUND 60 DEGREES
EARLY THIS MORNING. RECENT IR SATELLITE IMAGERY WAS SHOWING SOME
EXTENSIVE CLOUD COVER ACROSS THE AREA...WITH RADAR SHOWING A FEW
LIGHT SHOWERS AROUND ESPECIALLY ACROSS CENTRAL PIMA COUNTY. THAT
SAID...STILL EXPECTING HOTTER AFTERNOON TEMPERATURES TODAY EVEN
THOUGH THE RAIN CHANCES HAVE INCREASED AND A CLOUDY SKY WAS PRESENT.
THIS MOISTURE INCREASE WILL BE BRIEF AS DRIER AIR PUSHES IN FROM THE
EAST AND THE UPPER HIGH SHIFTS SOUTHWARD TOMORROW. THIS BREAK WILL
ALSO BE SHORT LIVED AS MODELS TRACK AN UPPER LEVEL DISTURBANCE
THROUGH MEXICO WHICH WILL LIKELY BRING A NOTICEABLE UPSWING IN
THUNDERSTORMS ACTIVITY OVER THE WEEKEND. HIGH TEMPERATURES WILL BE
ABOVE NORMAL THROUGHOUT THE FORECAST PERIOD...BUT THE WARMEST DAYS
WILL OCCUR TODAY THROUGH FRIDAY...WHEN READINGS WILL BE 8 TO 12 DEGS
ABOVE NORMAL. OTHERWISE...EXPECT HIGHS TO BE 3 TO 6 DEGS ABOVE
NORMAL. LOWS GENERALLY 4 TO 6 DEGS ABOVE NORMAL EACH DAY...BUT THE
WARMEST MORNINGS SHOULD OCCUR WEDNESDAY THROUGH FRIDAY.
&&
.TWC WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
VISIT US ON FACEBOOK...TWITTER...YOUTUBE...AND AT WEATHER.GOV/TUCSON
AREA FORECAST DISCUSSION
NWS PUEBLO CO
327 PM MDT WED JUL 23 2014
.SHORT TERM...(THIS EVENING THROUGH THURSDAY)
ISSUED AT 308 PM MDT WED JUL 23 2014
BOUNDARY FROM EARLY MORNING CONVECTION ACROSS NORTHEAST COLORADO
HAS PUSHED BACK WESTWARD INTO KIOWA AND NORTHEAST BENT COUNTY AS
OF 1 PM...AND EXTENDS TO THE NORTHEAST TO NEAR KLIC...TO
KDEN...THEN BACK TO THE SOUTHWEST TOWARDS THE NORTHERN BORDER OF
TELLER COUNTY. WHILE WESTERN PORTIONS OF THIS BOUNDARY HAVE
STALLED AND IS BEGINNING TO SHIFT BACK NORTHWARD...EASTERN
PORTIONS OF THIS BOUNDARY CONTINUE TO BACKDOOR WESTWARD INTO THE
SOUTHEAST PLAINS WITH DEW POINTS IN THE 60S BEHIND IT. TO THE
SOUTH OF THIS BOUNDARY...SOUTHERLY WINDS ARE INCREASING...BUT DEW
POINTS HAVE BEEN MORE STUBBORN TO MIX OUT TODAY...AND REMAIN IN
THE 40S AND 50S. STILL THINK THERE IS SOME FURTHER MIXING OUT THAT
WILL OCCUR DURING THE AFTERNOON AND EVENING HOURS...BUT HRRR AND
RAP13 APPEAR TO BE DRYING OUT DEW POINTS TOO VIGOROUSLY...EVEN IN
THE LATEST RUNS. THIS ELEVATES CONCERNS FOR POTENTIAL FOR A SLOW
MOVING THUNDERSTORM TO DEVELOP OVER THE WALDO BURN SCAR SOMETIME
THIS AFTERNOON AND EVENING. ANOTHER AREA OF CONCERN WILL BE ACROSS
THE WEST FORK BURN SCAR....THOUGH LATEST OBS OUT THAT WAY SHOW DEW
POINTS HAVE ALREADY DROPPED INTO THE 30S AND CONVECTION DOES NOT
LOOK ALL THAT STRONG YET. THUS APPEARS MAIN AREA TO MONITOR WILL
BE ACROSS TELLER AND EL PASO COUNTIES THIS EVENING...AND THREAT
AREA MAY END UP BEING JUST TO THE NORTH OF TELLER COUNTY. WILL
ALSO HAVE TO WATCH THE BOUNDARY ACROSS THE FAR SOUTHEAST PLAINS
FOR THUNDERSTORM DEVELOPMENT. MIXED LAYER CAPES ALONG THIS
BOUNDARY ARE AROUND 4000 J/KG OFF THE SPC MESO ANALYSIS...HOWEVER
THERE IS ALSO A FAIR OF CIN BEHIND THE OUTFLOW BOUNDARY AS WELL.
NONE OF THE SHORT RANGE MODELS ARE DEVELOPING THUNDERSTORMS ALONG
THIS BOUNDARY BENEATH THE UPPER HIGH. DEEP LAYER SHEAR IS
WEAK...SO ANY SEVERE POTENTIAL WOULD BE MORE LIKELY TO BE FROM A
PULSE TYPE SEVERE WHICH COULD PERSIST IF A STORM CAN ANCHOR TO THE
BOUNDARY. BUT WITH THE LACK OF FORCING THIS SEEMS TO BE A LOW END
PROBABILITY OF OCCURRENCE. HOWEVER...IT DEFINITELY BEARS WATCHING.
THUNDERSTORMS SHOULD DIMINISH THIS EVENING WITH LOSS OF
HEATING...THOUGH WITH MONSOON PLUME OVER THE MOUNTAINS WILL MAINTAIN
SOME ISOLATED POPS THROUGH THE NIGHT AS IS TYPICAL THIS TIME OF
YEAR.
FOR THURSDAY...UPPER RIDGE FLATTENS WHICH PUTS THE MONSOON PLUME
ALOFT ACROSS MOST OF CO. MODELS SUGGEST A WEAK SHORTWAVE WILL MOVE
OVERTOP THE RIDGE WHICH WILL HELP TO FIRE OFF THUNDERSTORMS ACROSS
THE MOUNTAINS THEN SEND THEM TO THE EAST ACROSS THE ADJACENT PLAINS.
BOTH NAM AND GFS SUGGEST NORTHERN PORTION SO OF THE FORECAST AREA
MAY SEE A BETTER CHANCE FOR THUNDERSTORMS TOMORROW...AND THIS WILL
PUT WALDO UNDER A SLIGHTLY HIGHER THREAT THAN TODAY. AGAIN...DEEP
LAYER SHEARS ARE WEAK...SO THREAT FOR SEVERE WEATHER OVERALL LOOKS
LOW. STORM MOTIONS SHOULD BE A LITTLE FASTER AND TOWARDS THE
EAST...BUT PROBABLY NOT FAST ENOUGH TO MITIGATE THE POTENTIAL
LOCALIZED FLASH FLOODING ON THE BURN SCARS SHOULD THEY TAKE AN
UNLUCKY STRIKE. SO ANOTHER DAY OF MONITORING THE WALDO BURN SCAR
CLOSELY WILL BE IN STORE. STORM STRENGTH WILL DEPEND ON HOW MUCH
SURFACE DEW POINTS MIX OUT...AND WITH WESTERLY FLOW OVER THE
AREA...UPPER 30S TO LOWER 40 DEW POINTS LOOK LIKELY...WHICH SHOULD
KEEP CAPE VALUES GENERALLY BELOW 1000 J/KG. HAVE KEPT HIGHER POPS
ACROSS THE CENTRAL MOUNTAINS AND PIKES PEAK REGION FOR TOMORROW.
OTHERWISE...WESTERLY FLOW SHOULD HELP DRY OUT SURFACE DEW POINTS
ACROSS THE PLAINS...WHICH SHOULD LIMIT CAPE AND THUNDERSTORM
COVERAGE. THIS MAY ALSO BE SUFFICIENT TO BOOST TEMPS INTO THE LOWER
100S ACROSS THE LOWER ARKANSAS RIVER VALLEY. HOWEVER...AN INCREASE
IN CONVECTIVE CLOUD COVER MAY ALSO LIMIT HEATING SOME...ESPECIALLY
FOR THE I-25 CORRIDOR SO HAVE KEPT PUB BELOW THE CENTURY MARK FOR
NOW. LOCATIONS FARTHER EAST SHOULD HAVE AN EASIER TIME OF HITTING
AROUND 100. -KT
.LONG TERM...(THURSDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 308 PM MDT WED JUL 23 2014
...MORE MONSOON NEXT WEEK...
THE EXTENDED FORECAST LOOKS PRETTY TYPICAL FOR LATE JULY...AS
AN UPPER RIDGE DOMINATES THE WEATHER THROUGH NEXT WEEK. BUT THERE
WILL BE TWO DISTINCT PATTERNS THAT WILL SHAPE OUR WEATHER.
THE FIRST HALF OF THE PERIOD WILL BE A CONTINUATION OF THE HOT AND
RELATIVELY DRY WEATHER WE HAVE BEEN EXPERIENCING THIS WEEK. A WEAK
FRONTAL SURGE WILL USHER IN A LITTLE MORE UPSLOPE THU NIGHT INTO
FRIDAY...AND THIS MAY HELP GENERATE A FEW MORE SHOWERS AND STORMS
OVER THE AREA FRIDAY AFTERNOON AND EVENING. WE WILL STILL BE UNDER
THE UPPER RIDGE AXIS...AND WITH TEMPS ALOFT STILL PRETTY
HIGH...EXPECT ANOTHER HOT DAY WITH TEMPS SOARING INTO THE HIGH 90S
OVER THE PLAINS. MAYBE EVEN A DEGREE OR TWO HOTTER ON SATURDAY
AS THE RIDGE EXPANDS A BIT TO THE NORTH.
THEN...A FRONTAL SURGE ASSOCIATED WITH A STRONG TROUGH DIGGING
OVER ERN CANADA WILL BRING A CHANGE TO OUR WEATHER BEGINNING
SUNDAY. IT LOOKS SOMEWHAT SIMILAR TO OUR LAST PERIOD OF WET
WEATHER...AS A STRONG UPSLOPE REGIME SETS UP OVER THE PLAINS AND
DEWPOINTS CLIMB FROM THE 40S AND LOWER 50S TO THE UPPER 50S AND
EVEN 60 DEGREE MARK BY EARLY NEXT WEEK. AT THIS TIME...IT LOOKS
LIKE SUNDAY AFTERNOON-EVE...WITH THE INITIAL SURGE...AND THEN
TUESDAY AFTERNOON AND EVE...WITH A SECONDARY PUSH OVER THE CENTRAL
PLAINS...WILL BE THE WETTEST DAYS. EVERY DAY WILL SEE THE
POTENTIAL FOR SOME LOCALLY HEAVY RAINFALL...BUT THOSE PERIODS ARE
PROBABLY THE HIGHEST THREAT FOR THE BURN SCARS AND POTENTIAL FLASH
FLOODING. COULD ALSO SEE SOME SVR STORMS ESPECIALLY ON TUESDAY OVR
THE PLAINS...AS NW FLOW ALOFT INCREASES A BIT AS THE RIDGE MOVE
WWD. TEMPS SHOULD SETTLE BACK INTO THE 70S AND 80S FROM SUNDAY
ONWARD THROUGH NEXT WEEK AS COOLER AND MOISTER AIR ARRIVES FROM
THE NORTH. ROSE
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z THURSDAY EVENING)
ISSUED AT 308 PM MDT WED JUL 23 2014
VFR CONDITIONS EXPECTED AT THE TAF SITES OVER THE NEXT 24 HOURS.
ISOLATED THUNDERSTORMS OVER THE MOUNTAINS COULD AFFECT KALS AND
KCOS LATE THIS AFTERNOON THROUGH THIS EVENING...SO WILL MAINTAIN
VCTS FOR THESE SITES. ERRATIC WIND GUSTS TO 45 KTS AND LOCALIZED
HEAVY RAINFALL WILL BE THE PRIMARY THREATS...BUT PROBABILITY LOOKS
TOO LOW AT THIS POINT TO INCLUDE IN A TEMPO GROUP. THUNDERSTORMS
WILL DIMINISH THIS EVENING. ANOTHER ROUND OF THUNDERSTORMS WILL
DEVELOP ACROSS THE MOUNTAINS ON THURSDAY. WINDS WILL INCREASE OUT
OF THE SOUTH TO SOUTHWEST DURING THE AFTERNOON AT 10-20 KTS. KCOS
MAY SEE A SLIGHTLY BETTER CHANCE OF SEEING -TSRA AT THE TERMINAL
DURING THE LATE AFTERNOON AND EARLY EVENING. -KT
&&
.PUB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...KT
LONG TERM...ROSE
AVIATION...KT
AREA FORECAST DISCUSSION
NWS TAUNTON MA
418 PM EDT WED JUL 23 2014
.SYNOPSIS...
A COLD FRONT WILL APPROACH THE REGION TONIGHT TRIGGERING SCATTERED
SHOWERS AND THUNDERSTORMS. A FEW STRONG THUNDERSTORMS ARE
POSSIBLE WEST OF THE CENTRAL HILLS. SHOWERS WILL LIKELY LINGER
INTO THURSDAY SOUTHEAST OF THE BOSTON TO PROVIDENCE CORRIDOR. HIGH
PRESSURE BUILDS WITH DRIER WEATHER FOR FRIDAY AND SATURDAY. AN
APPROACHING WARM FRONT SUNDAY WILL BRING MORE HUMID UNSETTLED
WEATHER FOR THE EARLY PART OF NEXT WEEK.
&&
.NEAR TERM /UNTIL 6 AM THURSDAY MORNING/...
* A FEW STRONG TO SEVERE STORMS POSSIBLE LATE THIS AFTERNOON INTO
THE EVENING HOURS *
415 PM MESO-UPDATE...
CONTINUING TO MONITOR FOR THE POTENTIAL FOR STRONG TO SEVERE
THUNDERSTORMS LATE THIS AFTERNOON INTO THE EVENING HOURS.
CURRENTLY THE COLD FRONT HAS JUST PUSHED THROUGH ITHACA NY UP TO
MONTPELIER VT...AND WILL CONTINUE A EASTWARD PROGRESSION TOWARDS
SOUTHERN NEW ENGLAND THROUGH THE REMAINDER OF THE DAY. OVER THE
NEXT FEW HOURS...BELIEVE A FEW ISOLATED SHOWERS AND THUNDERSTORMS
WILL POP- UP /JUST LIKE THEY ARE IN MOHAWK VALLEY REGION/. THEN
EXPECT A MORE BROKEN LINE SEGMENT TO MOVE THROUGH BY THE EVENING
HOURS AS THE FRONT MOVES CLOSER TO THE REGION.
LOOKING AT SPC MESO ANALYSIS...SB CAPE VALUES HAVE REACHED TO 2500
J/KG WITH NOT MUCH IN THE TERMS OF EFFECTIVE SHEAR FOR SOUTHERN NEW
ENGLAND. RAP 0-6 KM BULK SHEAR VALUES HAVE INCREASED
SLIGHTLY...AND ARE NOW 15-20 KTS. AS OF 20Z...THE STRONGER WIND
SHEAR AND UPPER LEVEL JET DYNAMICS ARE STILL SITUATED ACROSS
UPSTATE NEW YORK WHICH IS ALSO WHERE THE DEEP LAYER MOISTURE IS
LOCATED PER THE K-INDEX. HENCE WHY THE STORMS ARE SUSTAINING
THEMSELVES.
OVERVIEW AND INTO TONIGHT...
A COLD FRONT WILL PASS ACROSS THE NORTHEAST EARLY THIS EVENING AND
INTO THE EARLY OVERNIGHT HOURS. ALTHOUGH WE ARE CURRENTLY LACKING
MOISTURE AND SHEAR AS MENTIONED ABOVE...RAP GUIDANCE SHOWS THAT
BOTH OF THESE PARAMETERS WILL INCREASE CLOSER TO 00Z. THEREFORE
BELIEVE THAT SHOWERS AND STRONGER THUNDERSTORMS WILL DEVELOP AND
OVERSPREAD THE REGION AS THE FRONT PUSHES CLOSER TO SOUTHERN NEW
ENGLAND.
THROUGHOUT THE EVENING HOURS...THE MAIN CONCERN IS THE AMOUNT OF
INSTABILITY WITH LACK OF SOLAR HEATING BY THE LATE EVENING HOURS.
CURRENT THINKING THOUGH IS THAT SINCE THE ATMOSPHERE HAS NOT BEEN
WORKED OVER AND THE GUIDANCE SHOWS LINGER ELEVATED INSTABILITY
OVERNIGHT BELIEVE THAT THE THUNDERSTORM POTENTIAL WILL LINGER TIL
ABOUT MIDNIGHT. BY THEN THE STORMS WILL ENTER THE THE EASTERN
PORTION OF THE AREA WHICH IS BEING INFLUENCED BY THE ADVECTING
MARITIME AIR FROM TODAYS GUSTY SOUTHWEST WINDS.
STILL CANNOT RULE OUT THE POTENTIAL FOR SEVERE WEATHER BUT HAVE
INCREASING CONFIDENCE THAT AT LEAST STRONG STORMS WILL DEVELOP LATE
THIS AFTERNOON INTO THE EVENING HOURS. AFTER DISCUSSING WITH SPC
DECIDED TO ISSUE A WATCH FOR THE LOCATIONS THAT HAVE THE BEST
POTENTIAL TO SEE THE BEST MOISTURE/INSTABILITY AND SHEAR OVERLAPPING
ONE ANOTHER. THE MAIN THREATS ARE DAMAGING WINDS AND LOCALIZED
FLOODING AS PWATS CONTINUE TO INCREASE ABOVE 1.8 INCHES.
&&
.SHORT TERM /6 AM THURSDAY MORNING THROUGH 6 PM THURSDAY/...
THURSDAY...
COLD FRONT WILL SLOW DOWN DURING ITS PASSAGE ACROSS SOUTHERN NEW
ENGLAND THURSDAY MORNING. BOTH THE EC AND NAM SHOW A WAVE DEVELOPING
ALONG THE FRONT ALLOWING FOR THE SLOW DOWN WHILE THE GFS SEEMS TO BE
THE OUTLIER ON PUSHING THE FRONT THOUGH BY 12Z. IN FACT THE UPPER
LEVEL TROUGH AXIS IS STILL ACROSS UPSTATE NY BY 12/15Z RESULTING IN
CLOUDS AND THE CONFIDENCE THAT PRECIP WILL LINGER ESP FOR AREAS
SOUTH AND EAST OF THE BOS-PVD CORRIDOR. BELIEVE THAT BY 00Z THE
FRONT AND THE BULK OF THE PRECIP WILL BE OFFSHORE BUT CANNOT RULE
OUT A FEW LINGERING SHOWERS ESP FOR THE CAPE AND THE ISLANDS.
BECAUSE OF THE SLOW DOWN AND THE POTENTIAL WAVE
DEVELOPMENT...CANT RULE OUT THE POTENTIAL FOR EMBEDDED
THUNDERSTORMS DURING THE DAY.
DRIER AIR WILL WORK ITS WAY IN BEHIND THE FRONT RESULTING IN A
COOLER DAY WITH HIGHS WELL BELOW AVERAGE AND CLOSE TO 15 DEGREES
COOLER THEN TODAY. ASIDE FROM THE CLOUDS AND LINGERING PRECIP
CHANCES...SHOULD BE A PLEASANT DAY.
&&
.LONG TERM /THURSDAY NIGHT THROUGH WEDNESDAY/...
*/ HIGHLIGHTS...
- DRY AND SEASONABLE INTO FRIDAY
- RETURN OF WARM AND MUGGIER CONDITIONS FOR SATURDAY
- SIGNIFICANT WEATHER SATURDAY NIGHT INTO EARLY NEXT WEEK
- A RETURN OF DRY AND SEASONABLE WEATHER BY MIDWEEK
*/ OVERVIEW AND MODEL PREFERENCE...
SURPRISING PATTERN AS WE CLOSE OUT THE MONTH OF JULY! AS PRESENT NW
PACIFIC IMPULSE EJECTS E IT COUPLES WITH AN UPPER-LEVEL LOW PARKED
OVER NE CANADA RESULTING IN TROUGH ENHANCEMENT THROUGH THE GREAT
LAKES REGION. SUBSEQUENT DOWNSTREAM RIDGING OVER THE N-ATLANTIC AND
RIDGE STRENGTHENING OVER THE W-CONUS AHEAD OF A PACIFIC IMPULSE
BOTTLED IN THE GULF OF ALASKA...THE ATMOSPHERIC PATTERN BUCKLES.
WITH THE STAGNANT PATTERN IN PLACE...ANOMALOUS CONDITIONS PREVAIL AS
DECENT AGREEMENT AMONG ENSEMBLE MEMBERS SIGNAL A -3 TO -4 SD IN
HEIGHTS/TEMPERATURE/HUMIDITY.
BUT A NOTE OF CAUTION: SIMILAR ENSEMBLE MEMBERS OUT TO D8 AND INTO
EARLY AUGUST ARE EXHIBITING CONSIDERABLE SPREAD WITHIN NAO/PNA
TRENDS. IT IS WITH NO CERTAINTY AS TO HOW THIS PATTERN WILL EVOLVE.
THIS MAKES THE FORECAST OVER THE NE-CONUS DIFFICULT FURTHER OUT IN
TIME AS NEW ENGLAND ESPECIALLY FINDS ITSELF WITHIN THE E-PERIPHERY
OF THE AFOREMENTIONED TROUGH. JUST A SLIGHT WOBBLE OF THE OVERALL
BUCKLED PATTERN E OR W CAN RESULT IN CONSIDERABLE CHANGES IN THE
FORECAST.
FEEL THE DECENT AGREEMENT BETWEEN DETERMINISTIC AND ENSEMBLE MEMBERS
WARRANTS A BLEND OF MODEL GUIDANCE TOWARDS THE FORECAST. WILL HIT ON
THE MAIN POINTS ALONG WITH ANY PREFERRED GUIDANCE IN THE DAILIES
BELOW.
*/ DAY-TO-DAY DETAILS...
THURSDAY NIGHT THROUGH SATURDAY...
THINKING A DRY FORECAST PERIOD WITH THE RRQ OF THE UPPER-LEVEL JET
SHIFTING SE. FEEL THE COLD FRONT AND ATTENDANT WAVE LOW WILL REMAIN
OVER THE WATERS. SHOWERS DISSIPATING /IF ANY/ TOWARDS MIDNIGHT AS
DYNAMICS ARE SHUNTED OUT OF THE REGION.
OTHERWISE...HIGH PRESSURE AND LIGHT NW-FLOW SWEEPS ACROSS NEW
ENGLAND FRIDAY /SEA-BREEZES ALONG THE SHORES/ FOLLOWED BY RETURN
BREEZY S/SW-FLOW FOR THE REMAINDER OF THE PERIOD AS THE HIGH SLIDES
E/SE AND LOW PRESSURE BEGINS TO BUILD IN FROM THE W. SEASONABLE WX
INITIALLY...BUT EXPECT THE RETURN OF WARMER/MUGGIER CONDITIONS BY
SATURDAY. LOOKING CLEAR FOR FRIDAY...DIURNAL CUMULUS FOR SATURDAY.
SATURDAY NIGHT INTO EARLY NEXT WEEK...
THE EVOLUTION OF THE TROUGH AND THE PROXIMITY OF ITS E-PERIPHERY ARE
KEYS TO THE FORECAST /AS IS THE OFFSHORE ENHACING RIDGE ACROSS THE N-
ATLANTIC/. THE TRACK TIMING AND MORPHOLOGY OF INDIVIDUAL IMPULSES
THROUGH THE CYCLONIC FLOW WILL ULTIMATELY DETERMINE THE POTENTIAL
OUTCOMES FOR THE REGION.
FOR SATURDAY NIGHT INTO SUNDAY...SEEMINGLY AN INITIAL IMPULSE IS A
FOCUS FOR CONVECTIVE ACTIVITY /PERHAPS A MCS/ WHERE THERMAL/MOIST
AXES AND SUBSEQUENT INSTABILITY CONVERGE AT THE SURFACE AND ALONG
THE NOSE OF A LLJ REAR OF AN ATTENDANT WARM-FRONT. THE MORE ZONAL
REGIME ADVECTS THIS ACTIVITY W-TO-E. NEARLY UNI-DIRECTIONAL SHEAR
PRESENTS A THREAT OF DAMAGING WIND. BUT EARLY IN TIME AND LIKELY
ABUNDANCE OF CLOUD COVER...THREAT MAY BE LIMITED. HINTS OF MID-LEVEL
DRYING AND WAKE SUBSIDENCE? JUST A HUGE MESS. MAY BE LOOKING AT MORE
WIDESPREAD STRATIFORM WITH EMBEDDED THUNDERSTORMS. WHO KNOWS...JUST
A FIRST GUESS. BIGGEST CONCERN IS THE PLUME OF PWATS EXCEEDING 1.5
INCHES AND A POSSIBLE RISK OF FLASH FLOODING. SOME CONFIDENCE OF
THAT AT LEAST.
INTO MONDAY...THE LOW DEEPENS AS IT OCCLUDES OVER THE GREAT LAKES.
ALONG AND AHEAD OF THE COLD FRONT WITHIN WARM/MUGGY/UNSTABLE
CONDITIONS...CONVECTION IS LIKELY WITHIN AN ENVIRONMENT OF DEEP-
LAYER FORCING...BUT IT IS JUST TOO EARLY TO GO INTO DETAIL. MANY
QUESTIONS AS TO WHETHER THE ENVIRONMENT WILL DESTABILIZE BENEATH
STRONG SW-NE UNI-DIRECTIONAL SHEAR. APPEARS ACTIVITY MAY OCCUR IN
THE MORNING ONCE AGAIN FOLLOWED BY MID-LEVEL DRYING AND SUBSIDENCE.
YEESH. AGAIN...LOTS OF UNCERTAINTY. ONLY CONFIDENCE IS WITH SURGING
PWATS IN EXCESS OF 2-INCHES CONINTUING THE POSSIBLE RISK OF FLASH
FLOODING.
A FINAL NOTE...EVALUATING THE 23.0Z AND 23.12Z CIPS ANALOGS...BOTH
PING UPON POTENTIAL CONVECTIVE THREATS SUNDAY AND MONDAY. THE
PROBABILITIES OF SEVERE WEATHER IMPACTS HAVE SLIGHTLY INCREASED WITH
THE 23.12Z ANALOGS /UP TO 70-PERCENT/. SO WHILE THE ABOVE DISCUSSION
CONTAINS A FAIR AMOUNT OF UNCERTAINTY...THE FORECAST STILL WARRANTS
CLOSE MONITORING.
AT SOME POINT THE COLD FRONT SHOULD PUSH E BEHIND WHICH DRIER AND
COOLER AIR WRAPPING INTO THE OCCULUSION SHOULD PREVAIL RESULTING IN
SEASONABLE CONDITIONS FOR THE REGION. WHETHER THIS OCCURS ON TUESDAY
OR WEDNESDAY...JUST TOO UNCERTAIN.
&&
.AVIATION /20Z WEDNESDAY THROUGH MONDAY/...
FORECASTER CONFIDENCE LEVELS...
LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.
SHORT TERM /THROUGH THURSDAY/...
GENERALLY MODERATE CONFIDENCE ON FORECAST.
THROUGH 22Z...GENERALLY VFR.
AFTER 22Z INTO TONIGHT...MVFR CIGS AND VSBYS IN VICINITY OF SCT
TSTMS AHEAD OF A COLD FRONT. A FEW TSTMS MAY BRIEFLY LOWER
CIGS/VSBYS TO IFR LEVELS. ALSO...A FEW TSRA MAY PRODUCE STRONG
WIND GUSTS. THERE IS ALSO A MODERATE POTENTIAL FOR IFR CIGS
FORMING TONIGHT ACROSS THE CAPE AND ISLANDS.
THURSDAY...GENERALLY MVFR CIGS AND VSBYS TO START IN ANTICIPATED
RAIN OR SHOWERS. CONDITIONS WILL BE IMPROVING FROM NW TO SE
THROUGH MUCH OF THE DAY. EXCEPT ALONG AND SE OF A PYM-UUU LINE
WHICH MAY STAY IN LOWER CLOUDS THROUGH MUCH OF
THURSDAY...IMPROVING LATE.
KBOS TAF...HIGH CONFIDENCE. VFR THROUGH MOST OF THE DAY. TSTMS
POSSIBLE AFT 00Z TO THE N AND W OF BOS AND CLOSER TO THE AIRFIELD
ITSELF BY 03Z.
KBDL TAF...HIGH CONFIDENCE IN TAF. TSTMS POSSIBLE AFT 22Z. ANY
TSTMS COULD CONTAIN STRONG WIND GUSTS.
OUTLOOK...THURSDAY NIGHT THROUGH MONDAY...
THURSDAY NIGHT THROUGH SATURDAY...HIGH CONFIDENCE.
VFR. -RA MOVES OUT THURSDAY NIGHT UNDER NW FLOW. LIGHT WINDS AND
MOSTLY CLEAR ON FRIDAY /SEA-BREEZES ALONG THE SHORES/. SCT-BKN 5 KFT
CIGS SATURDAY WITH BREEZY S/SW WINDS.
SATURDAY NIGHT THROUGH MONDAY...LOW CONFIDENCE.
PERIODS OF RA/TSRA. MIX OF MVFR-IFR CONDITIONS...WORST OF WHICH
ANTICIPATED DURING OVERNIGHT PERIODS AND +RA. CONTINUED BLUSTERY
S/SW WINDS.
&&
.MARINE...
FORECASTER CONFIDENCE LEVELS...
LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.
SHORT TERM /THROUGH THURSDAY/...MODERATE CONFIDENCE.
THE SW FLOW WILL STRENGTHEN AHEAD OF A COLD FRONT TO PRODUCE GUSTS
APPROACHING 25 KT ACROSS MANY OF THE NEAR SHORE WATERS...THEREFORESCA
IS STILL IN EFFECT. SEAS MAY APPROACH 5 FEET EAST OF CAPE ANN THIS
EVENING. OTHERWISE WILL NEED TO MONITOR FOR AREAS OF FOG THAT MAY
DEVELOP ALONG THE SOUTH COASTAL WATERS TONIGHT.
OUTLOOK...THURSDAY NIGHT THROUGH MONDAY...
THURSDAY NIGHT THROUGH SATURDAY...HIGH CONFIDENCE.
TRANQUIL BOATING WEATHER. SOME SHOWERS MAY LINGER ALONG THE SE OUTER-
WATERS THURSDAY NIGHT...BUT SHOULD BE GOOD AFTER MIDNIGHT. HIGH
PRESSURE AND LIGHT NW-FLOW FRIDAY /SEA-BREEZES ALONG THE SHORES/.
WINDS VEER S/SW OVERNIGHT AND BECOME BREEZY DURING THE DAY SATURDAY.
SATURDAY NIGHT THROUGH MONDAY...LOW CONFIDENCE.
WEATHER TURNING SOUR. INCREASE S/SW WINDS AHEAD OF A STRONG LOW OVER
THE GREAT LAKES REGION WILL RESULT IN SIGNIFICANT WAVE HEIGHTS OVER
THE S-WATERS ESPECIALLY. SHOWERS/THUNDERSTORMS ANTICIPATED SOME OF
WHICH COULD BE STRONG.
&&
.BOX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
MA...NONE.
NH...NONE.
RI...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 8 PM EDT THIS EVENING FOR
ANZ230>237-251.
SMALL CRAFT ADVISORY UNTIL 8 AM EDT THURSDAY FOR ANZ250-254.
&&
$$
SYNOPSIS...DUNTEN/SIPPRELL
NEAR TERM...DUNTEN/SIPPRELL
SHORT TERM...DUNTEN
LONG TERM...SIPPRELL
AVIATION...DUNTEN/SIPPRELL
MARINE...DUNTEN/SIPPRELL
AREA FORECAST DISCUSSION
NWS TAUNTON MA
240 PM EDT WED JUL 23 2014
.SYNOPSIS...
WEATHER WILL BE HOT AND HUMID WEATHER TODAY AHEAD OF AN
APPROACHING COLD FRONT. THE FRONT WILL TRIGGER SCATTERED SHOWERS
AND THUNDERSTORMS LATE THIS AFTERNOON AND EVENING. A FEW STRONG
THUNDERSTORMS ARE POSSIBLE WEST OF I-495 AND NORTH OF THE MASS
PIKE AND I-84. SHOWERS WILL LIKELY LINGER INTO THURSDAY SOUTHEAST
OF THE BOSTON TO PROVIDENCE CORRIDOR. HIGH PRESSURE BUILDS WITH
DRIER WEATHER FOR FRIDAY AND SATURDAY. AN APPROACHING WARM FRONT
SUNDAY WILL BRING MORE HUMID UNSETTLED WEATHER FOR THE EARLY PART
OF NEXT WEEK.
&&
.NEAR TERM /UNTIL MIDNIGHT TONIGHT/...
* A FEW STRONG TO SEVERE STORMS POSSIBLE LATE THIS AFTERNOON INTO
THE EVENING HOURS *
CONTINUE TO MONITOR FOR THE POTENTIAL FOR STRONG TO SEVERE
THUNDERSTORMS LATE THIS AFTERNOON INTO THE LATE EVENING HOURS.
CURRENTLY THE COLD FRONT HAS JUST PUSHED THROUGH SYRACUSE NY AND
WILL CONTINUE ITS EASTWARD PROGRESSION TOWARDS SOUTHERN NEW
ENGLAND THROUGH THE AFTERNOON. AS IT APPROACHES ANTICIPATE
ISOLATED SHOWERS AND THUNDERSTORMS TO POP-UP AT FIRST BUT THEN A
MORE BROKEN LINE SEGMENT TO MOVE THROUGH BY THE EVENING HOURS.
LOOKING AT SPC MESO ANALYSIS...SB CAPE VALUES HAVE REACHED TO 2500
J/KG WITH NOT MUCH IN THE TERMS OF EFFECTIVE SHEAR FOR SOUTHERN
NEW ENGLAND. RAP 0-6KM BULK SHEAR VALUES ARE WEAK AS WELL...WITH
ONLY 10-15 KTS. AS OF 18Z...THE STRONGER WIND SHEAR AND UPPER
LEVEL JET DYNAMICS ARE STILL SITUATED UP NEAR THE COLD FRONT WHICH
IS ALSO WHERE THE DEEP LAYER MOISTURE IS LOCATED PER THE K-INDEX.
HENCE WHY THE STORMS ARE STARTING TO FIRE ACROSS UPSTATE NEW
YORK.
AS THE FRONT MOVES EASTWARD DURING THE AFTERNOON...SOME OF THESE
PARAMETERS WILL ALSO SHIFT EASTWARD. THE BIGGEST LIMITING FACTOR
FOR US RIGHT NOW IS THE LACK OF DEEP LAYER MOISTURE AND SHEAR...WHICH
IS NOT PROJECTED TO MOVE INTO THE REGION UNTIL CLOSER TO 00Z.
THEREFORE BELIEVE THAT JUST A FEW ISOLATED LOW TOP SHOWERS WILL
DEVELOP OVER THE NEXT FEW HOURS. AFTER 00Z THE FRONT WOULD HAVE
MOVED CLOSER TO THE REGION WITH BETTER SHEAR AND MOISTURE. THE ONE
THING TO BE CONCERN IS THE AMOUNT OF INSTABILITY. WITH THE
ATMOSPHERE NOT BEING WORKED OVER AND THE WARM...MOIST ATMOSPHERE
BOILING OVER THE REGION TODAY BELIEVE ONCE THE STORMS MOVE INTO
THE REGION THEY WILL EAT UP ANY INSTABILITY AND DEVELOP INTO
STRONG STORMS.
STILL CANNOT RULE OUT THE POTENTIAL FOR SEVERE WEATHER BUT HAVE
INCREASING CONFIDENCE THAT AT LEAST STRONG STORMS WILL DEVELOP.
AFTER DISCUSSING WITH SPC DECIDED TO ISSUE A WATCH FOR THE
LOCATIONS THAT ARE PROGGED TO HAVE THE BEST MOISTURE/INSTABILITY
AND SHEAR FOR WHEN/IF THUNDERSTORMS MOVE OVER THOSE LOCATIONS.
MAIN THREATS ARE DAMAGING WINDS AND LOCALIZED FLOODING AS PWATS
CONTINUE TO INCREASE ABOVE 1.8 INCHES.
&&
.SHORT TERM /MIDNIGHT THROUGH 6 PM THURSDAY/...
* SHOWERS WILL LIKELY LINGER ACROSS THE CAPE...ISLANDS AND
ADJACENT SE MASSACHUSETTS DURING MUCH OF THURSDAY
THURSDAY...
THE FRONT DEACCELERATES AS IT APPROACHES SOUTHEAST NEW ENGLAND AND
THEN A WAVE MOVES ALONG THE FRONT DURING THE DAY THURSDAY.
THUS...EXPECT SHOWERS TO LINGER THURSDAY MORNING ACROSS THE
SOUTHEAST HALF OF THE AREA AND FOR MOST OF THE DAY ACROSS CAPE
COD...THE ISLANDS AND ADJACENT SOUTHEAST MA.
WILL BE MUCH COOLER THURSDAY BEHIND THE FRONT...AND SOUTHEAST OF
THE BOSTON TO PROVIDENCE CORRIDOR CLOUDS WILL ALSO ACT TO CAP THE
TEMPERATURE. FOR MOST LOCATION...EXPECT HIGHS IN THE 70S ON
THURSDAY. THE ATMOSPHERE MAY BE MARGINALLY UNSTABLE ENOUGH TO
SUPPORT A FEW EMBEDDED THUNDERSTORMS OVER THE CAPE AND ISLANDS AS
WELL AS SOUTHEAST COASTAL WATERS ON THURSDAY.
&&
.LONG TERM /THURSDAY NIGHT THROUGH TUESDAY/...
BIG PICTURE...
FOUR FEATURES IN THE LARGE SCALE FLOW. TROUGH ALONG THE PACIFIC
NORTHWEST COAST...RIDGE EXTENDING FROM THE ROCKIES AND PLAINS TO
NORTHERN CANADA...CLOSED LOW OVER NORTHERN QUEBEC WITH TROUGH AXIS
ACROSS THE GREAT LAKES...BUILDING RIDGE OVER THE WESTERN ATLANTIC.
THE QUEBEC TROUGH HANGS OVER NORTHEAST NORTH AMERICA...THE TROUGH
AXIS AND COLDEST TEMPS ALOFT SWING ACROSS NEW ENGLAND THURSDAY
NIGHT/FRIDAY. THE PACIFIC NORTHWEST TROUGH RUNS OVER THE TOP OF THE
ROCKIES RIDGE...THEN MERGES WITH THE QUEBEC LOW OVER THE WEEKEND.
THIS DRAWS THE CLOSED LOW SOUTH OVER THE GREAT LAKES/NORTHEAST EARLY
NEXT WEEK. THE ATLANTIC HIGH PRESSURE MEANWHILE BLOCKS OFF THE
EASTWARD EXIT OF THIS MERGER. THE COMBINATION OF UPPER LOW PRESSURE
OVER THE LAKES AND HIGH PRESSURE OVER THE ATLANTIC CREATES A
SOUTHWEST FLOW UP THE EAST COAST FROM THE DEEP SOUTH FOR THE FIRST
HALF OF NEXT WEEK.
MODELS HAVE BEEN SHOWING CONSISTENCY BOTH RUN TO RUN AND WITH EACH
OTHER. THIS INCREASES CONFIDENCE IN THE OVERALL SOLUTION...BUT WITH
THE USUAL UNCERTAINTY IN TIMING SHORTWAVES MOVING THROUGH THE
FLOW. THIS IS ESPECIALLY TRUE FOR MONDAY AND TUESDAY.
THE DAILIES...
THURSDAY NIGHT...COLD FRONT LINGERS OFFSHORE WHILE THE UPPER JET
RIGHT ENTRANCE REGION MOVES OVERHEAD. THIS MAY SUPPORT A WAVE ALONG
THE FRONT DURING THE FIRST PART OF THE NIGHT...BUT THE JET SHIFTS
EAST AFTER MIDNIGHT AS SHOULD THE SUPPORTING DYNAMICS. WE WILL KEEP
CHANCE POPS ON THE CAPE AND ISLANDS EARLY IN THE NIGHT. IF THE JET
POSITION AT 00Z IS AS ADVERTISED...WE MAY BE A LITTLE CONSERVATIVE
ON EVENING POPS. OTHERWISE THE MOVEMENT OF THE UPPER JET SHOULD
TREND SOUTHERN NEW ENGLAND TO END ANY REMAINING PCPN AND BRING
CLEARING SKIES.
FRIDAY-SATURDAY... SURFACE HIGH PRESSURE BUILDS OVER THE REGION WITH
DRY WEATHER AND DEWPOINTS IN THE 50S. TEMPS AT THE TOP OF THE MIXED
LAYER WILL SUPPORT UPPER 70S TO MID 80S BOTH DAYS...A LITTLE WARMER
SATURDAY.
ONE CONCERN WILL BE SEA BREEZE DEVELOPMENT ON FRIDAY WHICH MAY HOLD
DOWN AFTERNOON TEMPS ON THE EASTERN COAST. OTHER CONCERN WOULD BE
THE PASSAGE OF THE UPPER TROUGH AND COLDER TEMPS ALOFT. THIS LATTER
CONCERN COULD DESTABILIZE THE AIRMASS AND PROMOTE CUMULUS
DEVELOPMENT. BUT MODEL RH FIELDS SHOW A DRY AIRMASS WITH RH VALUES
BELOW 700 MB BELOW 50 PERCENT. WILL KEEP SKY COVER LOW FRIDAY...THEN
INCREASING CIRRUS ON SATURDAY AFTERNOON.
SUNDAY... PACIFIC NORTHWEST SHORTWAVE DIGS AS IT APPROACHES THE
GREAT LAKES AND GENERATES A SURFACE LOW. STRONG LOW LEVEL JET IS
EXPECTED TO DEVELOP IN THE OHIO VALLEY SATURDAY WITH 35-40 KNOT
WINDS AT 850 AND 900 MB. AS THIS MOVES EAST IT WILL BRING DEEPER
MOISTURE TO NEW ENGLAND WITH PRECIP WATER VALUES CLIMBING TO 1.5
INCHES BY SUNDAY. THE LIFTING OF THIS AIR OVER THE DEPARTING SURFACE
LAYER WOULD GENERATE SOME SHOWERS/SCT TSTMS. WE WILL MENTION CHANCE
POPS LATER SATURDAY NIGHT INTO SUNDAY.
MONDAY-TUESDAY...THE MERGING LOW OVER THE GREAT LAKES SURFACE AND
ALOFT WILL SWING A FRONT THROUGH NEW ENGLAND. TIMING IS IN QUESTION
AT THIS POINT WITH THE GFS SHOWING FROPA MONDAY NIGHT WHILE THE
ECMWF STALLS THE FRONT OVER US. WITH NO CLEAR TREND ON A DAY 7
FORECAST...WE WILL STAY CLOSE TO BLENDED GUIDANCE SOLUTION OF
DIMINISHING POPS TUESDAY. BUT WITH LOW CONFIDENCE.
&&
.AVIATION /18Z WEDNESDAY THROUGH MONDAY/...
FORECASTER CONFIDENCE LEVELS...
LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.
SHORT TERM /THROUGH THURSDAY/...
GENERALLY MODERATE CONFIDENCE ON FORECAST.
THROUGH 22Z...GENERALLY VFR.
AFTER 22Z INTO TONIGHT...MVFR CIGS AND VSBYS IN VICINITY OF SCT
TSTMS AHEAD OF A COLD FRONT. A FEW TSTMS MAY BRIEFLY LOWER
CIGS/VSBYS TO IFR LEVELS. ALSO...A FEW TSRA MAY PRODUCE STRONG
WIND GUSTS. THERE IS ALSO A MODERATE POTENTIAL FOR IFR CIGS
FORMING TONIGHT ACROSS THE CAPE AND ISLANDS.
THURSDAY...GENERALLY MVFR CIGS AND VSBYS TO START IN ANTICIPATED
RAIN OR SHOWERS. CONDITIONS WILL BE IMPROVING FROM NW TO SE
THROUGH MUCH OF THE DAY. EXCEPT ALONG AND SE OF A PYM-UUU LINE
WHICH MAY STAY IN LOWER CLOUDS THROUGH MUCH OF
THURSDAY...IMPROVING LATE.
KBOS TAF...HIGH CONFIDENCE. VFR THROUGH MOST OF THE DAY. TSTMS
POSSIBLE AFT 00Z TO THE N AND W OF BOS AND CLOSER TO THE AIRFIELD
ITSELF AFT 03Z.
KBDL TAF...HIGH CONFIDENCE IN TAF. TSTMS POSSIBLE AFT 22Z. ANY
TSTMS COULD CONTAIN STRONG WIND GUSTS.
OUTLOOK...THURSDAY NIGHT THROUGH SUNDAY...MODERATE CONFIDENCE.
THURSDAY NIGHT THROUGH SATURDAY...VFR. LOCAL IFR POSSIBLE IN EARLY
MORNING FOG/LOW CLOUDS. POTENTIAL SEA BREEZE FRIDAY AFTERNOON.
SUNDAY...
VFR BUT WITH AREAS OF MVFR IN SHOWERS/TSTMS/FOG.
&&
.MARINE...
FORECASTER CONFIDENCE LEVELS...
LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.
SHORT TERM /THROUGH THURSDAY/...MODERATE CONFIDENCE.
THE SW FLOW WILL STRENGTHEN AHEAD OF A COLD FRONT TO PRODUCE GUSTS
APPROACHING 25 KT ACROSS MANY OF THE WATERS. SEAS MAY APPROACH 5
FEET EAST OF CAPE ANN...ACROSS THE E PORTION OF STELLWAGEN
BANK...AND E OF CAPE COD THIS AFTERNOON. ALTHOUGH THE WIND WAVE
WILL BE FORMED FROM THE SW FLOW...THERE IS ALSO A SWELL THAT IS
ENCROACHING THE COASTAL WATERS FROM THE EAST. ALTHOUGH OF FAIRLY
LOW AMPLITUDE OF LESS THAN 3 FEET...THE SWELL APPEARS TO BE
ENOUGH TO TRIGGER A MODERATE RIP CURRENT RISK ALONG PORTIONS OF
THE EAST FACING COAST. AREAS OF FOG MAY DEVELOP ALONG THE SOUTH
COASTAL WATERS TONIGHT.
OUTLOOK...THURSDAY NIGHT THROUGH SUNDAY...MODERATE CONFIDENCE.
THURSDAY NIGHT-FRIDAY-SATURDAY... NORTH TO NORTHEAST WIND THURSDAY
NIGHT BECOMES LIGHT FRIDAY WITH AFTERNOON SEA BREEZES DEVELOPING.
WINDS BECOME SOUTHWEST SATURDAY BUT REMAIN BELOW 25 KNOTS. SEAS 4
FEET OR LESS THROUGH THE PERIOD.
SUNDAY...A WARM FRONT APPROACHES THE WATERS WITH WARMER MORE HUMID
AIR AND WITH CLOUDS/SHOWERS/TSTMS. INCREASING SOUTH-SOUTHWEST WINDS
WITH GUSTS 20-22 KNOTS...APPROACHING SMALL CRAFT THRESHOLD. THESE
WINDS WILL ALSO BUILD SEAS ON THE EXPOSED WATERS TO 5 OR 6 FEET. A
SMALL CRAFT ADVISORY MAY BE NEEDED.
&&
.BOX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
MA...NONE.
NH...NONE.
RI...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 7 PM EDT THIS EVENING FOR
ANZ230>237-251.
SMALL CRAFT ADVISORY UNTIL 3 AM EDT THURSDAY FOR ANZ250-254.
&&
$$
SYNOPSIS...WTB/THOMPSON
NEAR TERM...DUNTEN
SHORT TERM...THOMPSON
LONG TERM...WTB
AVIATION...WTB/DUNTEN
MARINE...WTB/THOMPSON
AREA FORECAST DISCUSSION
NWS ALBANY NY
122 PM EDT WED JUL 23 2014
.SYNOPSIS...
HAZY...HAZY...HOT AND HUMID CONDITIONS EXPECTED THIS AFTERNOON AHEAD
OF A COLD FRONT. THIS COLD FRONT WILL BRING SHOWERS AND
THUNDERSTORMS TO THE AREA THROUGH THIS EVENING. BEHIND THE COLD
FRONT...COOLER AND LESS HUMID AIR IS EXPECTED FOR THURSDAY AND
FRIDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 1230 PM EDT...RADARS INDICATED A FEW CELLS POPPING UP ACROSS
NORTHERN HERKIMER AND PORTIONS OF CENTRAL NEW YORK. THE COLD FRONT
WAS WORKING THROUGH THE SAINT LAWRENCE VALLEY WITH PERHAPS A
PRE-FRONTAL TROUGH SETTING UP WELL TO THE WEST OF THE HUDSON
VALLEY.
TEMPERATURES WERE ALREADY INTO THE MID 80S IN THE HUDSON VALLEY SO
FOR THIS UPDATE WENT AHEAD AND BUMPED SOME OF THESE UP SEVERAL
DEGREES...WHICH WOULD MEAN THE CAPITAL REGION SHOULD APPROACH OR
EVEN ECLIPSE 90 DEGREES.
SO FOR THIS UPDATE...BUMPED TEMPERATURES UPWARD...RE-TOOLED HOURLY
GRIDS BUT LEFT THE REMAINDER OF THE FORECAST ALONE.
AREA 12Z SOUNDINGS SHOW QUITE A BIT OF INSTABILITY OVER THE
REGION...ESPECIALLY UPSTREAM...WHERE CONVECTION IS EXPECTED TO
INITIATE EARLY THIS AFTERNOON. WE ARE CAPPED AT MIDLEVELS HERE IN
EASTERN NY AND WESTERN NEW ENGLAND BUT AGAIN...UPSTREAM...THE CAP
IS MUCH LESS.
BOUNDARY LAYER WINDS ARE NOT TOO STRONG...BUT ENOUGH SO THAT
THUNDERSTORM DOWNDRAFTS WILL ENHANCE THE WINDS FOR A DAMAGING WIND
THREAT IN THUNDERSTORMS THROUGH THIS EVENING. LOW LEVEL WINDS ARE
LIGHT FROM THE SOUTH AND SOUTHEAST OVER EASTERN NY NOW...BUT WEST
TO SOUTHWEST IN CENTRAL AND WESTERN NY. WILL HAVE TO SEE IF LOW
LEVEL WINDS REMAIN SOUTH TO SOUTHEAST IN EASTERN NY...AS SHEAR
COULD BE ENOUGH FOR STRONGER ROTATING THUNDERSTORMS.
IT COULD BE A BUSY AFTERNOON AND EVENING WITH REGARD TO COVERAGE AN
STRENGTH OF THUNDERSTORMS...WITH A DAMAGING WIND AND LARGE HAIL
THREAT. THE LATEST HRRR INDICATED ACTIVITY IN OUR REGION SHOULD
BLOSSOM BETWEEN 2 AND 5 PM.
MORE ANALYSIS OF GUIDANCE WAS DESCRIBED IN THE PREVIOUS AFD WHICH
IS BELOW...
THE WARM SECTOR IS WELL ENTRENCHED ACROSS THE REGION AS METAR
DEWPOINTS WERE BETWEEN 65-70F AND VERY LITTLE IN THE WAY OF CLOUD
COVER. THIS WILL SET THE STAGE FOR AN ACTIVE WEATHER DAY ACROSS
THE REGION /AS ALREADY SEEN UPSTREAM WITH A LINE OF STRONG
CONVECTION UNDERWAY/ AS GOOD INSOLATION...HIGH MOISTURE CONTENT
AS PWATS CLIMB TO NEAR 2 INCHES...SBCAPES AT OR ABOVE 2K J/KG AND
DEEP LAYER SHEAR AROUND 30KTS /THE HIGHER VALUES ACROSS THE
NORTHERN PORTIONS OF THE REGION/ TO SUPPORT THE EXTENSION OF THE
SLIGHT RISK PER SPC COORDINATION ACROSS THE ENTIRE REGION. THE
MAIN THREAT REMAINS FROM DAMAGING WIND GUSTS AND/OR WET
MICROBURSTS GIVEN THE PRECIP LOADING IN A VERY MOIST COLUMN. HAIL
POTENTIAL LOOKS LOW AT THIS TIME AS WET BULB FREEZING LEVELS PER
THE BUFR PROFILES ARE EXPECTED AT OR ABOVE 13K FEET. WE WILL
RETAIN THE ENHANCED WORDING FOR HEAVY RAINFALL AND GUSTY WINDS IN
THE GRIDS ALONG WITH THE STRONGLY WORDED HWO. NCEP MODEL SUITE IS
IN GOOD AGREEMENT WITH THE TIMING OF THE FROPA WHICH REACHES OUR
DACKS REGION AROUND THE LUNCH HOUR...CAPITAL REGION BETWEEN 2PM-
4PM...AND THE MID HUDSON VALLEY AND NW CT BETWEEN 5PM-8PM.
IN THE WAKE OF FROPA...WINDS SHIFT TO WEST AND NORTHWEST BEFORE
MIDNIGHT. HOWEVER...A WAVE IS EXPECTED TO DEVELOP ALONG THE
BOUNDARY WHICH WILL SLOW DOWN THE FORWARD PROGRESS SOMEWHAT TO
KEEP CHC-SCT POPS SOUTH OF I90. WHILE THIS FROPA WILL USHER IN
MORE STABLE AND LESS HUMID CONDITIONS...LOW LEVEL MOISTURE CONTENT
REMAINS HIGH SO WE WILL RETAIN THE PARTLY-MOSTLY CLOUDY SKIES IN
THE FORECAST.
HIGHS TODAY WILL BE NEAR 90 IN MOST VALLEY LOCATIONS...WITH HEAT
INDICES INTO THE MID AND UPPER 90S. HIGHER TERRAIN WILL SEE HIGHS IN
THE MID TO UPPER 80S...EXCEPT COOLER ACROSS THE ADRIONDACKS WHERE
CLOUDS AND SHOWERS SHOULD KEEP HIGHS BELOW 80. A SOUTH WIND 5 TO 15
MPH WILL DO LITTLE TO STIFLE THE HEAT. HOWEVER...THE SHOWERS AND
THUNDERSTORMS WILL BEGIN TO COOL US DOWN AFTER 400 PM.
&&
.SHORT TERM /THURSDAY THROUGH FRIDAY/...
A MORE STABLE...COOLER AND LESS HUMID AIR MASS ADVECTS INTO THE
REGION THURSDAY AND FRIDAY AS HIGH PRESSURE BUILDS INTO THE
REGION. RESIDUAL CLOUD COVER ACROSS THE REGION...ESPECIALLY ACROSS
THE SOUTHERN PORTIONS OF THE REGION...WILL MIX OUT TO PARTLY
CLOUDY/SUNNY CONDITIONS. CYCLONIC FLOW ALOFT REMAINS ALOFT A H850
TEMPS DIP BACK TO AROUND 10C. HIGHS THURSDAY WILL AVERAGE AT OR
JUST BELOW 80F FOR VALLEY LOCATIONS WITH THURSDAY NIGHT LOWS INTO
THE 50S WITH 40S ACROSS THE DACKS AND PORTIONS OF THE MOHAWK
VALLEY. HIGHS FRIDAY REBOUND BACK INTO THE LOWER 80S FOR VALLEY
LOCATIONS...MID-UPR 70S ELSEWHERE.
&&
.LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/...
THE LONG TERM PERIOD LOOKS RATHER UNSETTLED STARTING WITH THE SECOND
HALF OF THE WEEKEND.
FOR FRIDAY NIGHT AND SATURDAY EXPECT DRY AND SEASONABLE CONDITIONS
AS A RIDGE OF HIGH PRESSURE SLIDES OFF THE EASTERN SEABOARD. EXPECT
LOWS FRIDAY NIGHT IN THE 50S WITH HIGHS ON SATURDAY IN THE MID 70S
TO MID 80S.
START TO INCREASE POPS FROM SLIGHT CHANCE SATURDAY EVENING TO CHANCE
POPS LATE SATURDAY AS FA STARTS TO BE CONVERGED UPON BY SEVERAL LOW
PRESSURE SYSTEMS ONE PASSING THROUGH THE MID ATLANTIC REGION AND A
SECOND ONE PASSING THROUGH THE UPPER GREAT LAKES REGION. LOWS
SATURDAY NIGHT ARE EXPECTED TO BE IN THE MID 50S TO MID 60S.
SUNDAY THROUGH TUESDAY LOOKS TO BE ACTIVE AS THE SERIES OF LOW
PRESSURE SYSTEMS CONVERGE ACROSS THE NORTHEAST. TIMING AND LOCATION
OF INDIVIDUAL LOW PRESSURE SYSTEMS DIFFER AMONGST THE MODELS. SO AT
THIS POINT IN TIME WILL PLACE CHANCE POPS IN THE GRIDS THROUGH THE
PERIOD WITH MAINLY AFTERNOON AND EVENING SHOWERS AND THUNDERSTORMS.
HIGHS ARE EXPECTED TO RANGE FROM THE MID 70S TO MID 80S SUNDAY AND
MONDAY AND IN THE UPPER 60S TO UPPER 70S ON TUESDAY. LOWS ARE
EXPECTED TO BE IN THE MID 50S MID 60S.
&&
.AVIATION /18Z WEDNESDAY THROUGH MONDAY/...
A BROKEN BAND OF SHOWERS AND THUNDERSTORMS IS DEVELOPING IN NORTHERN
AND WESTERN NY...WITH MORE ISOLATED ACTIVITY IN CENTRAL NY. A STRONG
COLD FRONT WILL SUPPORT MORE WIDESPREAD SHOWERS AND THUNDERSTORMS
TRACKING ACROSS THE REGION LATER THIS AFTERNOON AND EVENING. OUTSIDE
OF SHOWERS AND THUNDERSTORMS...CONDITIONS SHOULD BE VFR. TIMING OF
THUNDERSTORMS IN TAFS BASED ON CURRENT TRENDS AND TIMING INDICATED
IN MESOSCALE MODELS. IT LOOKS LIKE AROUND 21Z-22Z AT KGFL AND
KALB...22Z-23Z AT KPSF AND 23Z-24Z AT KPOU. SOME LOCALIZED
CONVERGENCE ASSOCIATED WITH THE MOHAWK/HUDSON RIVER INTERSECTION
NEAR THE KALB AIRPORT COULD SPARK A LOCALIZED SHOWER OR STORM BEFORE
22Z BUT WILL WATCH TRENDS CAREFULLY. WILL AMEND ONCE THUNDERSTORMS
DEVELOP AND CAN BE TIMED MORE PRECISELY... BUT INDICATED MVFR
CONDITIONS IN THUNDERSTORMS. THERE COULD BE SOME BRIEF IFR
CONDITIONS IN BRIEF BURSTS AND AGAIN WILL AMEND IF THESE CONDITIONS
LOOK IMMINENT LATER THIS AFTERNOON AND EVENING. THERE COULD BE GUSTY
VARIABLE WINDS AROUND 25 KT OR MORE IN THUNDERSTORMS AS WELL.
ONCE THE THUNDERSTORMS END...KEEPING VCSH FOR A FEW HOURS FOR
LINGERING ACTIVITY...BUT LONGER...THROUGH ABOUT 09Z AT KPOU SINCE
THE FRONT MAY SLOW ITS PROGRESS IN SOUTHERN AREAS. SOME FOG MAY
FORM AFTER SOME CLEARING AT KGFL...KALB AND KPSF TOWARD DAYBREAK BUT
ONLY INDICATING 6SM BR UNTIL WE CAN ANALYZE SHORT TERM TRENDS BEHIND
THE FRONT AFTER SUNSET.
AFTER SUNRISE TOMORROW...VFR EVERYWHERE...BUT WILL HAVE TO SEE IF
ANY SHOWERS LINGER AROUND KPOU AFTER 09Z IF THE PROGRESS OF THE
FRONT SLOWS.
SOUTH TO SOUTHWEST WINDS THIS AFTERNOON AT 10 KT OR LESS COULD BE
VARIABLE AND GUSTY TO 25 KT OR MORE IN THUNDERSTORMS. THE WINDS
SHOULD SHIFT TO WEST AND NORTHWEST BY THIS EVENING AT LESS THAN 10
KT...THE DIMINISH TO LESS THAN 6 KT AND TREND TOWARD NORTH.
TOMORROW MORNING...WINDS SHOULD BE NORTH NORTHWEST TO NORTH
NORTHEAST AT LESS THAN 10 KT.
OUTLOOK...
THURSDAY NIGHT: NO OPERATIONAL IMPACT. NO SIG WX.
FRIDAY: NO OPERATIONAL IMPACT. NO SIG WX.
FRIDAY NIGHT: NO OPERATIONAL IMPACT. NO SIG WX.
SATURDAY: NO OPERATIONAL IMPACT. NO SIG WX.
SATURDAY NIGHT: LOW OPERATIONAL IMPACT. CHANCE OF SHRA.
SUNDAY: MODERATE OPERATIONAL IMPACT. CHANCE OF SHRA...TSRA.
SUNDAY NIGHT: MODERATE OPERATIONAL IMPACT. CHANCE OF SHRA.
MONDAY: MODERATE OPERATIONAL IMPACT. CHANCE OF SHRA...TSRA.
&&
.FIRE WEATHER...
SHOWERS AND THUNDERSTORMS WILL MOVE ACROSS THE REGION TODAY ALONG
AND AHEAD OF A COLD FRONT. RELATIVELY HIGH MOISTURE CONTENT AHEAD
OF THIS BOUNDARY WILL KEEP RH VALUES AT OR ABOVE 50 PERCENT. THE
RH VALUES TONIGHT AT BETTER THAN 80 PERCENT.
THE SURFACE WIND WILL BE SOUTH TO SOUTHWEST THIS MORNING AT 5 TO 10
MPH...THEN BECOMING SOUTHWEST TO WEST MID DAY AT 5 TO 15 MPH WITH
SOME GUSTS TO 20 MPH. WINDS SHIFT TO A WEST THEN NORTHWEST
DIRECTION TONIGHT.
&&
.HYDROLOGY...
SHOWERS AND THUNDERSTORM WILL OCCUR ACROSS THE AREA AS A COLD
FRONT APPROACHES AND INTERACTS WITH THE VERY WARM AND HUMID AIR
MASS IN PLACE ACROSS THE REGION. PRECIPITABLE WATER VALUES ARE
EXPECTED TO INCREASE NEAR 2 INCHES...SO ANY STORM WILL CAPABLE OF
VERY HEAVY DOWNPOURS WHICH COULD CAUSE LOCALIZED FLOODING OF LOW
LYING AND POOR DRAINAGE AREAS. HAVE CONTINUED ENHANCED WORDING FOR
THE HEAVY RAINFALL TO THE FORECAST FOR THIS AFTERNOON AND EVENING
AND WILL RETAIN THIS MENTION IN OUR HAZARDOUS WEATHER OUTLOOK.
WITH THE PASSAGE OF THE COLD FRONT...A COOLER AND LESS HUMID AIR
WILL BE USHERED IN. EXPECTED SOME LINGERING SHOWERS INTO THURSDAY
MORNING AS THE FRONT WILL BE SLOW TO MOVE OFF TO THE EAST. THEN
LOOKING AT DRY WEATHER INTO AT LEAST THE FIRST HALF OF THE
WEEKEND. THE WEATHER WILL TURN UNSETTLED AS WE HEAD INTO THE
SECOND HALF OF THE WEEKEND AND INTO NEXT WEEK.
FOR DETAILS ON SPECIFIC AREA RIVERS AND LAKES...INCLUDING OBSERVED
AND FORECAST RIVER STAGES AND LAKE ELEVATIONS...PLEASE VISIT THE
ADVANCED HYDROLOGIC PREDICTION SERVICE /AHPS/ GRAPHS ON OUR WEBSITE.
&&
.ALY WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...NONE.
MA...NONE.
VT...NONE.
&&
$$
SYNOPSIS...HWJIV/BGM
NEAR TERM...HWJIV/BGM/NAS
SHORT TERM...BGM
LONG TERM...11
AVIATION...NAS
FIRE WEATHER...BGM
HYDROLOGY...BGM
AREA FORECAST DISCUSSION
NWS ALBANY NY
1230 PM EDT WED JUL 23 2014
.SYNOPSIS...
HAZY...HAZY...HOT AND HUMID CONDITIONS EXPECTED THIS AFTERNOON AHEAD
OF A COLD FRONT. THIS COLD FRONT WILL BRING SHOWERS AND
THUNDERSTORMS TO THE AREA THROUGH THIS EVENING. BEHIND THE COLD
FRONT...COOLER AND LESS HUMID AIR IS EXPECTED FOR THURSDAY AND
FRIDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 1230 PM EDT...RADARS INDICATED A FEW CELLS POPPING UP ACROSS
NORTHERN HERKIMER AND PORTIONS OF CENTRAL NEW YORK. THE COLD FRONT
WAS WORKING THROUGH THE SAINT LAWRENCE VALLEY WITH PERHAPS A
PRE-FRONTAL TROUGH SETTING UP WELL TO THE WEST OF THE HUDSON
VALLEY.
TEMPERATURES WERE ALREADY INTO THE MID 80S IN THE HUDSON VALLEY SO
FOR THIS UPDATE WENT AHEAD AND BUMPED SOME OF THESE UP SEVERAL
DEGREES...WHICH WOULD MEAN THE CAPITAL REGION SHOULD APPROACH OR
EVEN ECLIPSE 90 DEGREES.
SO FOR THIS UPDATE...BUMPED TEMPERATURES UPWARD...RE-TOOLED HOURLY
GRIDS BUT LEFT THE REMAINDER OF THE FORECAST ALONE.
AREA 12Z SOUNDINGS SHOW QUITE A BIT OF INSTABILITY OVER THE
REGION...ESPECIALLY UPSTREAM...WHERE CONVECTION IS EXPECTED TO
INITIATE EARLY THIS AFTERNOON. WE ARE CAPPED AT MIDLEVELS HERE IN
EASTERN NY AND WESTERN NEW ENGLAND BUT AGAIN...UPSTREAM...THE CAP
IS MUCH LESS.
BOUNDARY LAYER WINDS ARE NOT TOO STRONG...BUT ENOUGH SO THAT
THUNDERSTORM DOWNDRAFTS WILL ENHANCE THE WINDS FOR A DAMAGING WIND
THREAT IN THUNDERSTORMS THROUGH THIS EVENING. LOW LEVEL WINDS ARE
LIGHT FROM THE SOUTH AND SOUTHEAST OVER EASTERN NY NOW...BUT WEST
TO SOUTHWEST IN CENTRAL AND WESTERN NY. WILL HAVE TO SEE IF LOW
LEVEL WINDS REMAIN SOUTH TO SOUTHEAST IN EASTERN NY...AS SHEAR
COULD BE ENOUGH FOR STRONGER ROTATING THUNDERSTORMS.
IT COULD BE A BUSY AFTERNOON AND EVENING WITH REGARD TO COVERAGE AN
STRENGTH OF THUNDERSTORMS...WITH A DAMAGING WIND AND LARGE HAIL
THREAT. THE LATEST HRRR INDICATED ACTIVITY IN OUR REGION SHOULD
BLOSSOM BETWEEN 2 AND 5 PM.
MORE ANALYSIS OF GUIDANCE WAS DESCRIBED IN THE PREVIOUS AFD WHICH
IS BELOW...
THE WARM SECTOR IS WELL ENTRENCHED ACROSS THE REGION AS METAR
DEWPOINTS WERE BETWEEN 65-70F AND VERY LITTLE IN THE WAY OF CLOUD
COVER. THIS WILL SET THE STAGE FOR AN ACTIVE WEATHER DAY ACROSS
THE REGION /AS ALREADY SEEN UPSTREAM WITH A LINE OF STRONG
CONVECTION UNDERWAY/ AS GOOD INSOLATION...HIGH MOISTURE CONTENT
AS PWATS CLIMB TO NEAR 2 INCHES...SBCAPES AT OR ABOVE 2K J/KG AND
DEEP LAYER SHEAR AROUND 30KTS /THE HIGHER VALUES ACROSS THE
NORTHERN PORTIONS OF THE REGION/ TO SUPPORT THE EXTENSION OF THE
SLIGHT RISK PER SPC COORDINATION ACROSS THE ENTIRE REGION. THE
MAIN THREAT REMAINS FROM DAMAGING WIND GUSTS AND/OR WET
MICROBURSTS GIVEN THE PRECIP LOADING IN A VERY MOIST COLUMN. HAIL
POTENTIAL LOOKS LOW AT THIS TIME AS WET BULB FREEZING LEVELS PER
THE BUFR PROFILES ARE EXPECTED AT OR ABOVE 13K FEET. WE WILL
RETAIN THE ENHANCED WORDING FOR HEAVY RAINFALL AND GUSTY WINDS IN
THE GRIDS ALONG WITH THE STRONGLY WORDED HWO. NCEP MODEL SUITE IS
IN GOOD AGREEMENT WITH THE TIMING OF THE FROPA WHICH REACHES OUR
DACKS REGION AROUND THE LUNCH HOUR...CAPITAL REGION BETWEEN 2PM-
4PM...AND THE MID HUDSON VALLEY AND NW CT BETWEEN 5PM-8PM.
IN THE WAKE OF FROPA...WINDS SHIFT TO WEST AND NORTHWEST BEFORE
MIDNIGHT. HOWEVER...A WAVE IS EXPECTED TO DEVELOP ALONG THE
BOUNDARY WHICH WILL SLOW DOWN THE FORWARD PROGRESS SOMEWHAT TO
KEEP CHC-SCT POPS SOUTH OF I90. WHILE THIS FROPA WILL USHER IN
MORE STABLE AND LESS HUMID CONDITIONS...LOW LEVEL MOISTURE CONTENT
REMAINS HIGH SO WE WILL RETAIN THE PARTLY-MOSTLY CLOUDY SKIES IN
THE FORECAST.
HIGHS TODAY WILL BE NEAR 90 IN MOST VALLEY LOCATIONS...WITH HEAT
INDICES INTO THE MID AND UPPER 90S. HIGHER TERRAIN WILL SEE HIGHS IN
THE MID TO UPPER 80S...EXCEPT COOLER ACROSS THE ADRIONDACKS WHERE
CLOUDS AND SHOWERS SHOULD KEEP HIGHS BELOW 80. A SOUTH WIND 5 TO 15
MPH WILL DO LITTLE TO STIFLE THE HEAT. HOWEVER...THE SHOWERS AND
THUNDERSTORMS WILL BEGIN TO COOL US DOWN AFTER 400 PM.
&&
.SHORT TERM /THURSDAY THROUGH FRIDAY/...
A MORE STABLE...COOLER AND LESS HUMID AIR MASS ADVECTS INTO THE
REGION THURSDAY AND FRIDAY AS HIGH PRESSURE BUILDS INTO THE
REGION. RESIDUAL CLOUD COVER ACROSS THE REGION...ESPECIALLY ACROSS
THE SOUTHERN PORTIONS OF THE REGION...WILL MIX OUT TO PARTLY
CLOUDY/SUNNY CONDITIONS. CYCLONIC FLOW ALOFT REMAINS ALOFT A H850
TEMPS DIP BACK TO AROUND 10C. HIGHS THURSDAY WILL AVERAGE AT OR
JUST BELOW 80F FOR VALLEY LOCATIONS WITH THURSDAY NIGHT LOWS INTO
THE 50S WITH 40S ACROSS THE DACKS AND PORTIONS OF THE MOHAWK
VALLEY. HIGHS FRIDAY REBOUND BACK INTO THE LOWER 80S FOR VALLEY
LOCATIONS...MID-UPR 70S ELSEWHERE.
&&
.LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/...
THE LONG TERM PERIOD LOOKS RATHER UNSETTLED STARTING WITH THE SECOND
HALF OF THE WEEKEND.
FOR FRIDAY NIGHT AND SATURDAY EXPECT DRY AND SEASONABLE CONDITIONS
AS A RIDGE OF HIGH PRESSURE SLIDES OFF THE EASTERN SEABOARD. EXPECT
LOWS FRIDAY NIGHT IN THE 50S WITH HIGHS ON SATURDAY IN THE MID 70S
TO MID 80S.
START TO INCREASE POPS FROM SLIGHT CHANCE SATURDAY EVENING TO CHANCE
POPS LATE SATURDAY AS FA STARTS TO BE CONVERGED UPON BY SEVERAL LOW
PRESSURE SYSTEMS ONE PASSING THROUGH THE MID ATLANTIC REGION AND A
SECOND ONE PASSING THROUGH THE UPPER GREAT LAKES REGION. LOWS
SATURDAY NIGHT ARE EXPECTED TO BE IN THE MID 50S TO MID 60S.
SUNDAY THROUGH TUESDAY LOOKS TO BE ACTIVE AS THE SERIES OF LOW
PRESSURE SYSTEMS CONVERGE ACROSS THE NORTHEAST. TIMING AND LOCATION
OF INDIVIDUAL LOW PRESSURE SYSTEMS DIFFER AMONGST THE MODELS. SO AT
THIS POINT IN TIME WILL PLACE CHANCE POPS IN THE GRIDS THROUGH THE
PERIOD WITH MAINLY AFTERNOON AND EVENING SHOWERS AND THUNDERSTORMS.
HIGHS ARE EXPECTED TO RANGE FROM THE MID 70S TO MID 80S SUNDAY AND
MONDAY AND IN THE UPPER 60S TO UPPER 70S ON TUESDAY. LOWS ARE
EXPECTED TO BE IN THE MID 50S MID 60S.
&&
.AVIATION /18Z WEDNESDAY THROUGH MONDAY/...
FOR TODAY...MAINLY VFR CONDITIONS...BUT SOME INTERMITTENT MVFR
CEILINGS AT KPSF FROM 12Z-14Z. SHOWERS AND THUNDERSTORMS WILL OCCUR
ACROSS THE AREA AS A COLD FRONT APPROACHES AND INTERACTS WITH THE
VERY WARM AND HUMID AIR MASS IN PLACE ACROSS THE REGION. THERE ARE
NOW INDICATIONS THAT THE FRONT WILL SLOW DOWN AS A WAVE OF LOW
PRESSURE MOVES NORTHEAST ALONG IT. HAVE USED PROB30 GROUPS FOR MVFR
CONDITIONS...BORDERING ON IFR...TO ADDRESS THE TIMING OF THE
CONVECTION...FOR THE LATE AFTERNOON INTO THE EVENING HOURS.
SOME STORMS MAY BECOME STRONG TO SEVERE DURING THE AFTERNOON AND
EVENING HOURS.
WE WILL START OFF WITH A SOUTH-SOUTHWEST WIND OF 5 TO 10 KNOTS TODAY
SHIFTING MORE TO THE WEST AND THEN NORTHWEST IN THE WAKE OF THE COLD
FRONT DURING THE EVENING HOURS.
OUTLOOK...
THURSDAY NIGHT: NO OPERATIONAL IMPACT. NO SIG WX.
FRIDAY: NO OPERATIONAL IMPACT. NO SIG WX.
FRIDAY NIGHT: NO OPERATIONAL IMPACT. NO SIG WX.
SATURDAY: NO OPERATIONAL IMPACT. NO SIG WX.
SATURDAY NIGHT: LOW OPERATIONAL IMPACT. CHANCE OF SHRA.
SUNDAY: MODERATE OPERATIONAL IMPACT. CHANCE OF SHRA...TSRA.
SUNDAY NIGHT: MODERATE OPERATIONAL IMPACT. CHANCE OF SHRA.
MONDAY: MODERATE OPERATIONAL IMPACT. CHANCE OF SHRA...TSRA.
&&
.FIRE WEATHER...
SHOWERS AND THUNDERSTORMS WILL MOVE ACROSS THE REGION TODAY ALONG
AND AHEAD OF A COLD FRONT. RELATIVELY HIGH MOISTURE CONTENT AHEAD
OF THIS BOUNDARY WILL KEEP RH VALUES AT OR ABOVE 50 PERCENT. THE
RH VALUES TONIGHT AT BETTER THAN 80 PERCENT.
THE SURFACE WIND WILL BE SOUTH TO SOUTHWEST THIS MORNING AT 5 TO 10
MPH...THEN BECOMING SOUTHWEST TO WEST MID DAY AT 5 TO 15 MPH WITH
SOME GUSTS TO 20 MPH. WINDS SHIFT TO A WEST THEN NORTHWEST
DIRECTION TONIGHT.
&&
.HYDROLOGY...
SHOWERS AND THUNDERSTORM WILL OCCUR ACROSS THE AREA AS A COLD
FRONT APPROACHES AND INTERACTS WITH THE VERY WARM AND HUMID AIR
MASS IN PLACE ACROSS THE REGION. PRECIPITABLE WATER VALUES ARE
EXPECTED TO INCREASE NEAR 2 INCHES...SO ANY STORM WILL CAPABLE OF
VERY HEAVY DOWNPOURS WHICH COULD CAUSE LOCALIZED FLOODING OF LOW
LYING AND POOR DRAINAGE AREAS. HAVE CONTINUED ENHANCED WORDING FOR
THE HEAVY RAINFALL TO THE FORECAST FOR THIS AFTERNOON AND EVENING
AND WILL RETAIN THIS MENTION IN OUR HAZARDOUS WEATHER OUTLOOK.
WITH THE PASSAGE OF THE COLD FRONT...A COOLER AND LESS HUMID AIR
WILL BE USHERED IN. EXPECTED SOME LINGERING SHOWERS INTO THURSDAY
MORNING AS THE FRONT WILL BE SLOW TO MOVE OFF TO THE EAST. THEN
LOOKING AT DRY WEATHER INTO AT LEAST THE FIRST HALF OF THE
WEEKEND. THE WEATHER WILL TURN UNSETTLED AS WE HEAD INTO THE
SECOND HALF OF THE WEEKEND AND INTO NEXT WEEK.
FOR DETAILS ON SPECIFIC AREA RIVERS AND LAKES...INCLUDING OBSERVED
AND FORECAST RIVER STAGES AND LAKE ELEVATIONS...PLEASE VISIT THE
ADVANCED HYDROLOGIC PREDICTION SERVICE /AHPS/ GRAPHS ON OUR WEBSITE.
&&
.ALY WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...NONE.
MA...NONE.
VT...NONE.
&&
$$
SYNOPSIS...HWJIV/BGM
NEAR TERM...HWJIV/BGM/NAS
SHORT TERM...BGM
LONG TERM...11
AVIATION...11
FIRE WEATHER...BGM
HYDROLOGY...BGM
AREA FORECAST DISCUSSION
NWS MIAMI FL
143 PM EDT WED JUL 23 2014
.AVIATION...
RADAR IS SHOWING SIGNS THAT CONVECTION IS FINALLY PUSHING TO THE
WEST OF THE EASTERN TAF SITES. HOWEVER, THERE ARE STILL A FEW
CONVECTIVE CELLS DEVELOPING ALONG THE COAST. SO HAVE PLACED TEMPO
FOR KPBI AND KFXE, AND LEFT VCTS IN FOR THE REMAINING EASTERN TAF
SITES FOR ANOTHER COUPLE OF HOURS. EXPECT MOSTLY VFR CONDITIONS,
EXCEPT WHEN THE SITES ARE BEING AFFECTED BY CONVECTIVE SHOWERS AND
THUNDERSTORMS THIS AFTERNOON. ONCE THEY MOVE OUT, CONDITIONS WILL
BE VFR THROUGH TOMORROW MORNING.
&&
.PREV DISCUSSION... /ISSUED 947 AM EDT WED JUL 23 2014/
UPDATE...
PLAN TO MAKE SOME ADJUSTMENTS TO THE POPS OVER AT LEAST THE
INTERIOR AS THEY SEEM A BIT HIGH BASED ON CURRENT TRENDS. WATER
VAPOR IMAGERY AND THE 12Z MFL SOUNDING BOTH SHOW SIGNIFICANT
DRYING HAS OCCURRED ABOVE THE 500MB LEVEL. HOWEVER, THE LOW LEVELS
REMAIN QUITE MOIST WITH A PWAT OF JUST UNDER 2 INCHES AND WITH
DIURNAL HEATING BEGINNING IN EARNEST THIS MORNING ALREADY HAVE
CONVECTION FIRING ACROSS THE EAST COAST METRO REGION. LOOKING AT
THE CONVECTIVE PARAMETERS, THE CAPE IS OVER 2000 J/KG, 500MB
TEMPERATURE WARMED TO 4.7C AND THE MID LEVEL LAPSE RATE IS NEAR
5.5C/KG. WITH THE EXCEPTION OF THE CAPE AND THE PWAT, THESE
NUMBERS ARE VERY UNIMPRESSIVE AND BELOW THE AVERAGE FOR MID/LATE
JULY. STILL, IT SEEMS THE HIGH PWAT AND CAPE ALONG WITH STRONG
DIURNAL HEATING WILL SOMEWHAT COUNTERACT THE OTHER LOW CONVECTIVE
ELEMENTS. THE HRRR HAS BEGUN TO SHOW LESS OVERALL COVERAGE OVER
THE INTERIOR FOR THIS AFTERNOON THAN THE 70-80% ORIGINALLY
ADVERTISED, SO WITH THE LESS THAN AMPLE PARAMETERS WILL ONLY LOWER
THE POPS SLIGHTLY UNTIL LATER TRENDS DICTATE OTHERWISE.
KOB
PREV DISCUSSION... /ISSUED 400 AM EDT WED JUL 23 2014/
SYNOPSIS...
SLIGHT DRIER AIR WILL MOVE INTO THE AREA THIS AFTERNOON AND
TONIGHT...AS HIGH PRESSURE BUILDS IN. THIS HIGH PRESSURE WILL
DOMINATE SOUTH FLORIDA WEATHER AT LEAST INTO EARLY NEXT WEEK.
SHORT TERM /TODAY THROUGH FRIDAY/...
HIGH PRESSURE CENTERED NORTH AND EAST OF THE BAHAMAS WILL
GRADUALLY STRENGTHEN TODAY...WITH DRIER AIR SPILLING NORTHWARD
INTO SOUTH FLORIDA THIS AFTERNOON AND TONIGHT. STILL PLENTY OF
MOISTURE FOR SEA-BREEZE TO INDUCE SCATTERED TO NUMEROUS SHOWERS
AND THUNDERSTORMS...BUT COVERAGE WILL BE LESS THAN PREVIOUS FEW
DAYS...ESPECIALLY OVER EAST COAST URBAN AREAS WHERE DRY AIR WILL
BE FIRST TO REACH. THIS DRIER THAN NORMAL AIRMASS WILL REMAIN OVER
SOUTH FLORIDA THROUGH THE SHORT TERM...AS RIDGE AXIS ORIENTS OVER
THE PENINSULA. RAIN CHANCES WILL BE LOWER THAN NORMAL BOTH
THURSDAY AND FRIDAY...AND SHOULD BE MOSTLY FOCUSED OVER THE
INTERIOR WHERE SEA-BREEZES INTERACT.
LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/...
DEEP LAYER RIDGE WILL STRENGTHEN FURTHER OVER THE WEEKEND.
SCATTERED DAYTIME SHOWERS AND THUNDERSTORMS WILL STILL BE
POSSIBLE...BUT ACTIVITY WILL BE LESS WIDESPREAD THAN TYPICAL OF
LATE JULY RAINY SEASON. EARLY NEXT WEEK...AN UPPER LEVEL TROUGH
AND ASSOCIATED COLD FRONT WILL DIG INTO THE DEEP SOUTH AND
SOUTHEAST CONUS. AFOREMENTIONED HIGH PRESSURE SHOULD KEEP THESE
FEATURES FROM HAVING MUCH IMPACT ON SOUTH FLORIDA...BUT OVERALL
WINDS BECOMING MORE SOUTHERLY/SOUTHWESTERLY...AS OPPOSED TO
SOUTHEAST...MAY ALLOW FOR CONVECTION TO SPREAD TOWARD EAST COAST
MORE. SLIGHTLY WARMER TEMPERATURES COULD ALSO RESULT.
MARINE...
HIGH PRESSURE BUILDING OVER THE WATERS WILL RESULT LIGHT
WINDS...SOUTH AT 10 KTS OR LESS...AND SEAS OF 2 FEET OR
LESS...THROUGH THE WEEKEND. THUNDERSTORMS WILL BE LESS WIDESPREAD
THAN PREVIOUS FEW DAYS...BUT SCATTERED ACTIVITY IS STILL POSSIBLE
THROUGHOUT THE PERIOD.
&&
.PRELIMINARY POINT TEMPS/POPS...
WEST PALM BEACH 77 90 78 90 / 10 20 10 30
FORT LAUDERDALE 80 90 81 91 / 10 30 10 30
MIAMI 79 91 78 91 / 20 30 10 30
NAPLES 76 91 77 92 / 20 30 20 30
&&
.MFL WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
AM...NONE.
GM...NONE.
&&
$$
SHORT TERM...30/KOB
LONG TERM....23/SK
AVIATION...13/SI
AREA FORECAST DISCUSSION
NWS PEACHTREE CITY GA
138 PM EDT WED JUL 23 2014
.PREV DISCUSSION... /ISSUED 1052 AM EDT WED JUL 23 2014/
UPDATE...
UPPER LOW CONTINUES ACROSS THE LA COAST THIS MORNING. AT THE
SURFACE...A WEAK BOUNDARY REMAINS ACROSS SOUTHERN GA. REGIONAL
RADAR TRENDS SHOW SOME ISOLD SHOWERS DEVELOPING ACROSS THE
NORTHERN METRO AREA. LATEST RUNS OF THE HRRR LOOK PRETTY GOOD WITH
THE HIGHEST POPS ACROSS THE NORTHERN HALF OF THE CWFA THIS
AFTERNOON...WITH COVERAGE OF STORMS REMAINING ISOLD TO SCT. 12Z
SOUNDING SHOWS HIGH PWATS AND BL WINDS BELOW 15KT...SO ANY STORMS
THAT DEVELOP WILL BE SLOW MOVERS AND CAPABLE OF PRODUCING LOCALLY
HEAVY RAINFALL.
PREV DISCUSSION... /ISSUED 727 AM EDT WED JUL 23 2014/
SHORT TERM /TODAY THROUGH THURSDAY/...
/ISSUED AT 503 AM EDT WED JUL 23 2014/
MODELS CONTINUE IN GOOD AGREEMENT THROUGH THE SHORT TERM. WIDELY
SCATTERED SHOWERS CONTINUE ACROSS MAINLY NORTH GA EARLY THIS MORNING
AND WHILE THIS WILL DIMINISH TOWARD SUNRISE...EXPECT CONVECTION TO
INCREASE AGAIN LATE THIS MORNING AND AFTERNOON. THE BEST CHANCES
WILL BE ACROSS NORTH GA. A SHORT WAVE WILL MOVE INTO THE CWA
THURSDAY ALONG WITH AN ASSOCIATED WEAK FRONT. THIS WILL BE ENOUGH TO
INCREASE CHANCES OF TSTORMS TO HIGH CHANCE TO LIKELY ACROSS THE
CWA...MAINLY DURING THE AFTERNOON ON THURSDAY. AT THIS TIME WE DO
NOT EXPECT SEVERE THUNDERSTORMS THURSDAY...HOWEVER BRIEF HEAVY RAIN
IS POSSIBLE.
17
LONG TERM /THURSDAY NIGHT THROUGH TUESDAY/...
/ISSUED AT 503 AM EDT WED JUL 23 2014/
ACTIVE PATTERN IS EXPECTED TO CONTINUE THROUGH THE EXTENDED
PERIODS WITH SEVERAL FEATURES IMPACTING THE AREA...BUT MODELS ARE
IN BETTER AGREEMENT WITH SHOWING RELATIVELY QUIET PERIODS IN
BETWEEN. HAVE ACTUALLY DECREASED POPS SLIGHTLY FRIDAY AND INTO THE
WEEKEND BEHIND THE AFOREMENTIONED FRONT. ALTHOUGH SEVERAL MODELS
PUSH THE FRONT THROUGH THE ENTIRE CWA BY SATURDAY...THERE IS STILL
SOME UNCERTAINTY REGARDING THE POSITION OF THE FRONT AND
ASSOCIATED MOISTURE ACROSS SOUTH GEORGIA. AS A RESULT...HAVE
CONTINUED MENTION OF CHANCE POPS ACROSS THE FAR SOUTH AND
SOUTHEAST CWA ON SATURDAY. MOISTURE RETURNS TO THE AREA SUNDAY AS
NEXT SHORTWAVE APPROACHES AND LONGWAVE TROUGH STARTS TO SET UP
OVER THE EASTERN UNITED STATES. CHANCE POPS SUNDAY CONTINUE INTO
EARLY WEEK AND THEN EXIT QUICKLY LATE MONDAY AS SECOND FRONT
PUSHES THROUGH. LONGWAVE TROUGH MAINTAINS ITS POSITION OVER THE
EASTERN U.S. THROUGH MID WEEK...AND WITH SURFACE HIGH ACROSS THE
AREA BEHIND THE FRONT...LOWER PRECIP CHANCES AND COOLER
TEMPERATURES ARE IN STORE.
IN GENERAL...EXPECT A SLIGHT WARMING TREND OVER THE WEEKEND...THEN
BACK TO NEAR NORMAL OR SLIGHTLY BELOW NORMAL TEMPERATURES WITH THE
SECOND FRONT EARLY NEXT WEEK.
31
&&
.AVIATION...
18Z UPDATE...
SCATTERED SHOWERS HAVE DEVELOPED ACROSS NORTHERN GA THIS
AFTERNOON. BETTER COVERAGE SHOULD BE UP TO THE NORTH...BUT ENOUGH
CONFIDENCE THAT THERE WILL BE ENOUGH CELLS IN THE VICINITY OF ATL.
MODELS ARE NOT PROGGING IFR/LIFR CIGS OVERNIGHT. DO THINK THAT
THERE WILL BE ENOUGH LOW LEVEL MOISTURE FOR SOME SCT MVFR CIGS
THO. A COLD FRONT WILL MOVE THROUGH ON THURSDAY...WITH BETTER
COVERAGE OF PRECIPITATION.
//ATL CONFIDENCE...18Z UPDATE...
HIGH CONFIDENCE ALL ELEMENTS.
&&
.PRELIMINARY POINT TEMPS/POPS...
ATHENS 90 70 89 70 / 30 20 60 30
ATLANTA 88 71 87 71 / 30 20 60 30
BLAIRSVILLE 80 66 82 64 / 40 30 60 20
CARTERSVILLE 87 69 87 68 / 40 30 60 20
COLUMBUS 91 72 90 73 / 30 20 60 30
GAINESVILLE 86 70 87 69 / 40 20 60 20
MACON 91 72 91 72 / 30 20 60 30
ROME 87 70 87 68 / 50 30 60 20
PEACHTREE CITY 89 70 87 69 / 30 20 60 30
VIDALIA 93 74 94 74 / 30 20 60 40
&&
.FFC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS GOODLAND KS
1140 AM MDT WED JUL 23 2014
.UPDATE...
ISSUED AT 1050 AM MDT WED JUL 23 2014
THUNDERSTORMS CONTINUE ALONG PERIPHERY OF LARGE H5 TROUGH CENTERED
SOUTHWEST OF CWA. INTENSITY HAS NOTICEABLY DIMINISHED OVER THE
PAST HOUR OR SO AND THINK TREND WILL LIKELY CONTINUE WITH OVERALL
WEAK FORCING EXPECTED TO WEAKEN FURTHER.
STRONG OUTFLOW BOUNDARY HAS CREATED FAIRLY GUSTY EASTERLY WINDS
AND A PERIOD OF LIGHT DRIZZLE AS IT MOVED THROUGH ACROSS WESTERN
CWA. THIS WILL CONTINUE TO DECREASE IN COVERAGE AND ALLOW FOR THE
WINDS TO ONCE AGAIN BECOME SOUTHEASTERLY IN RESPONSE TO LEE TROUGH.
TEMPS ARE VERY MUCH A CONCERN AS STORMS...OUTFLOW AND FOG HAVE
HELD TEMPS DOWN CONSIDERABLY. HAVE LOWERED MAXES A FEW
DEGREES...BUT WITH STRONG JULY SUN THINK THINGS WILL REBOUND
QUICKLY WITH CLEARING.
UPDATE ISSUED AT 700 AM MDT WED JUL 23 2014
STRONG THUNDERSTORMS HAVE REDEVELOPED TO THE NORTH ACROSS WEST
CENTRAL NEBRASKA ALONG AND NORTH OF AREA OF H8 TO H75 PERSISTENT
WAA. WHILE FORCING GENERALLY DECREASES INTO THE CWA AS WINDS ALOFT
DIMINISH...AM CONCERNED ABOUT CURRENT RAP DEPICTION OF NEARLY 3000
J/KG OF ELEVATED CAPE AND LITTLE CINH LOCATED AROUND H725. WHILE
FORCING MAY BE DIMINISHED...WILL NOT BE OUT OF THE QUESTION FOR
THESE STORMS TO PROPAGATE INTO THIS POTENTIALLY UNSTABLE AIRMASS.
HAVE INCREASED/REFINED POPS TO ACCOUNT FOR THIS BUT THERE STILL IS
A LOT OF QUESTION WITH REGARDS TO HOW FAR SOUTH STORMS WILL MAKE
IT. GIVEN AFOREMENTIONED INSTABILITY...SEVERE STORMS WILL BE
POSSIBLE THROUGH THE MORNING HOURS.
UPDATE ISSUED AT 552 AM MDT WED JUL 23 2014
NO MAJOR UPDATES FOR THIS ESTF ISSUANCE. CONTINUING MENTION OF
PATCHY FOG IN FORECAST AS SPOTTY FOG SHOWING UP IN LATEST OBS.
LATEST RADAR LOOP SHOWING ISOLATED/SCATTERED RW/TRW ALONG PORTIONS
OF OUR CWA...SO HAVE LEFT IN CURRENT MENTION OF PRECIPITATION.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 215 AM MDT WED JUL 23 2014
SCATTERED THUNDERSTORMS ALONG NORTHERN BORDER ZONES THIS MORNING IN
CONNECTION WITH FRONTAL BOUNDARY...REMNANTS WHICH HAS BEEN
MEANDERING OVER KANSAS/NEBRASKA OVERNIGHT. MOST OF THE PRECIPITATION
WILL OCCUR OUT OF CWA...BUT HAVE INCLUDED SL CHANCE POPS FOR TRW
THRU 14Z-15Z FOR NORTHERN ZONES. HIGH DEWPTS AROUND THE AREA
CREATING MUGGY CONDITIONS WHICH COULD TRANSLATE INTO A FEW HOURS OF
PATCHY FOG THIS MORNING UNTIL SUNRISE SO HAVE MENTIONED FOR ALL
AREAS. MID/UPPER LEVEL RIDGE WILL RE-ASSERT ITSELF AGAIN ACROSS THE
CWA TODAY INTO TONIGHT. WITH THIS...EXPECTING YET ANOTHER HOT DAY
ACROSS THE AREA...WITH MID TO UPPER 90S FOR HIGHS...AND MID TO
UPPER 60S FOR OVERNIGHT LOWS. ONLY WESTERN ZONES WILL POTENTIALLY
SEE A LATE DAY REPRIEVE AS ISOLATED TRW MAY DEVELOP AS LEE-SIDE
TROUGH SETS UP ALONG EASTERN ROCKIES.
.LONG TERM...(THURSDAY THROUGH TUESDAY)
ISSUED AT 215 AM MDT WED JUL 23 2014
FOR THE THURSDAY THROUGH FRIDAY NIGHT PERIODS...THE CWA WILL
CONTINUE TO SEE MAINLY HOT AND DRY CONDITIONS AS BROAD H5/H7 RIDGE
REMAINS OVER THE AREA. DOWN TO THE SURFACE...LEE-SIDE TROUGH
DEVELOPS AND MOVES ACROSS THE REGION THURSDAY/THURSDAY NIGHT WITH A
WEAK SHORTWAVE WORKING OVER TOP OF RIDGE...AS MODELS DO SHOW SOME
FLATTENING POTENTIAL FRIDAY/FRIDAY NIGHT WHICH MAY BRING A CHANCE
FOR CONVECTION. WITH 925 MB TEMPERATURES REMAINING IN THE +35C TO
+40C...FORECASTED HIGHS WILL STAY IN THE 95-100 DEGREE RANGE FOR
BOTH DAYS. OVERNIGHT LOWS WILL STAY IN 60S...WARMEST IN EASTERN
ZONES. BOTH HIGHS/LOWS WILL BE AFFECTED AT TIMES FROM EXPECTED CLOUD
COVER/PRECIP...BUT WILL BE LOCALIZED AS WILL BE KEEPING SL CHANCE
POPS IN FOR TRW. BEST CHANCES FOR CONVECTION THURSDAY/THURSDAY NIGHT
WILL BE SPLIT DUE TO SLOW MOVEMENT OF TROUGH OFF THE ROCKIES...AND
FOR FRIDAY/FRIDAY NIGHT THE MAIN FOCUS WILL SHIFT TO NORTHERN
SECTIONS DUE TO TRACK OF SHORTWAVE.
COOLING TREND LATE THIS WEEKEND INTO NEXT WEEK WITH A FEW CHANCES
FOR PRECIP ALONG THE WAY. HAVE GENERALLY LOWERED POPS ACROSS THE
FORECAST PERIOD...BUT AM STILL CONFIDENT WE WILL SEE SOME CONVECTIVE
ACTIVITY MOST DAYS. UPPER FLOW WILL BE MAINLY OUT OF THE NORTHWEST
AS AN UPPER HIGH OVER THE FOUR CORNERS REGION RETROGRADES WEST A BIT
AND A RIDGE DEVELOPS ACROSS THE GREAT BASIN REGION EARLY NEXT WEEK.
COLD FRONT ARRIVING OVER THE WEEKEND WILL BRING RELATIVELY COOLER
TEMPS AND /THANKFULLY/ LOWER DEW POINTS.
SATURDAY...WEAK IMPULSES MOVING ACROSS THE COLORADO ROCKIES COULD
PROVIDE AMPLE LARGE SCALE LIFT FOR ISOLATED STORMS TO DEVELOP DURING
THE DAY. PREVIOUS GUIDANCE HAD INDICATED SUFFICIENT INSTABILITY FOR
STRONG TO SEVERE THUNDERSTORMS...BUT IT SEEMS THE ECMWF IS NOW
LEANING TOWARDS WHAT HAS RECENTLY BEEN A VERY DRY GFS. GEM REMAINS
STEADFAST IN SOME INSTABILITY DUE TO BETTER MOISTURE THROUGHOUT THE
COLUMN...SO WILL CONTINUE TO KEEP SOME POPS IN PLACE DESPITE THE DRY
GFS AND ECMWF. SATURDAY NIGHT IS A DIFFERENT STORY...WITH
GEFS/ECMWF/GEM INDICATING INCREASED MOISTURE AVAILABILITY AS COLD
FRONT PUSHES THROUGH FROM THE NORTH/NORTHWEST. THIS SHOULD SUPPORT
AT LEAST ISOLATED STORMS LATE IN THE DAY...POSSIBLY LASTING THROUGH
THE NIGHT. UPPER LEVEL SUPPORT FOR LARGE SCALE LIFT ACROSS THE
LATEST GUIDANCE IS NOT AS SUPPORTIVE ON LATEST GUIDANCE AS PREVIOUS
RUNS HAVE BEEN...SO A BIT LOWER CONFIDENCE THAN USUAL FOR OVERNIGHT
STORMS.
SUNDAY...COOLER FOLLOWING FROPA. SOME CLOUDS DURING THE MORNING
CLEARING OUT TO A MOSTLY SUNNY DAY. SOME AFTERNOON CONVECTION
POSSIBLE BEHIND THE FRONT...THOUGH THERE IS CHANCE THE MODERATELY
STRONG CAP COULD PREVENT DEVELOPMENT. GUIDANCE IN GOOD AGREEMENT ON
AN INVERTED-V SOUNDING...SO WITH ANY STORMS THAT DEVELOP GUSTY WINDS
COULD BE POSSIBLE. A FEW STORMS COULD LAST INTO THE EVENING...ENDING
BEFORE MIDNIGHT. HIGHS LIMITED TO THE MID/UPPER 80S. OVERNIGHT LOWS
DIPPING BELOW 60 IN SOME SPOTS FOR THE FIRST TIME IN A WEEK.
MONDAY AND TUESDAY...SLIGHT CHANCE FOR SHOWERS/STORMS BOTH
DAYS...WITH THE BETTER CHANCE FOR PRECIP ON TUESDAY. A NUMBER OF
WEAK MID-LEVEL IMPULSES WILL MOVE ACROSS THE CENTRAL ROCKIES AND
INTO THE CENTRAL HIGH PLAINS IN THE NORTH-NORTHWESTERLY FLOW. IN
THIS FAVORABLE ENVIRONMENT EXPECT MOSTLY TERRAIN-BASED STORMS TO
FIRE IN THE DAY AND MOVE EAST INTO THE AREA DURING THE LATE
AFTERNOON. LOW LEVEL FLOW WILL BE OUT OF THE SOUTH WHICH WILL
INCREASE LOW LEVEL MOISTURE...AND THUS PROVIDE SOME INSTABILITY FOR
STORMS TO WORK WITH. 0-6KM BULK SHEAR IN THE 30-40KT RANGE COULD
HELP SUSTAIN STORMS THROUGH THE LATE NIGHT HOURS. HIGHS IN THE
MID/UPPER 80S.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z THURSDAY AFTERNOON)
ISSUED AT 1137 AM MDT WED JUL 23 2014
MVFR CONDITIONS AT KGLD SHOUKLD END BEFORE 20Z AS AREA OF LOW
CLOUDS BEHIND THIS MORNINGS OUTFLOW BOUNDARY ARE ALREADY BEGINNING
TO BREAK UP AND EXPECT THIS TO CONTINUE. WITH COOLER...MORE STABLE
AIR IN PLACE DO NOT THINK THERE WILL BE MUCH OF A THUNDERSTORM
THREAT AT EITHER SITE AND EXPECT VFR FLIGHT CATEGORIES TO PREVAIL.
SMALL THREAT FOR RADIATIONAL FOG AT MCK TOMORROW MORNING...BUT
FAR TOO LOW TO INCLUDE IN TAF ATTM.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
UPDATE...JRM
SHORT TERM...JN
LONG TERM...JJM
AVIATION...JRM
AREA FORECAST DISCUSSION
NWS GOODLAND KS
1055 AM MDT WED JUL 23 2014
.UPDATE...
ISSUED AT 1050 AM MDT WED JUL 23 2014
THUNDERSTORMS CONTINUE ALONG PERIPHERY OF LARGE H5 TROUGH CENTERED
SOUTHWEST OF CWA. INTENSITY HAS NOTICEABLY DIMINISHED OVER THE
PAST HOUR OR SO AND THINK TREND WILL LIKELY CONTINUE WITH OVERALL
WEAK FORCING EXPECTED TO WEAKEN FURTHER.
STRONG OUTFLOW BOUNDARY HAS CREATED FAIRLY GUSTY EASTERLY WINDS
AND A PERIOD OF LIGHT DRIZZLE AS IT MOVED THROUGH ACROSS WESTERN
CWA. THIS WILL CONTINUE TO DECREASE IN COVERAGE AND ALLOW FOR THE
WINDS TO ONCE AGAIN BECOME SOUTHEASTERLY IN RESPONSE TO LEE TROUGH.
TEMPS ARE VERY MUCH A CONCERN AS STORMS...OUTFLOW AND FOG HAVE
HELD TEMPS DOWN CONSIDERABLY. HAVE LOWERED MAXES A FEW
DEGREES...BUT WITH STRONG JULY SUN THINK THINGS WILL REBOUND
QUICKLY WITH CLEARING.
UPDATE ISSUED AT 700 AM MDT WED JUL 23 2014
STRONG THUNDERSTORMS HAVE REDEVELOPED TO THE NORTH ACROSS WEST
CENTRAL NEBRASKA ALONG AND NORTH OF AREA OF H8 TO H75 PERSISTENT
WAA. WHILE FORCING GENERALLY DECREASES INTO THE CWA AS WINDS ALOFT
DIMINISH...AM CONCERNED ABOUT CURRENT RAP DEPICTION OF NEARLY 3000
J/KG OF ELEVATED CAPE AND LITTLE CINH LOCATED AROUND H725. WHILE
FORCING MAY BE DIMINISHED...WILL NOT BE OUT OF THE QUESTION FOR
THESE STORMS TO PROPAGATE INTO THIS POTENTIALLY UNSTABLE AIRMASS.
HAVE INCREASED/REFINED POPS TO ACCOUNT FOR THIS BUT THERE STILL IS
A LOT OF QUESTION WITH REGARDS TO HOW FAR SOUTH STORMS WILL MAKE
IT. GIVEN AFOREMENTIONED INSTABILITY...SEVERE STORMS WILL BE
POSSIBLE THROUGH THE MORNING HOURS.
UPDATE ISSUED AT 552 AM MDT WED JUL 23 2014
NO MAJOR UPDATES FOR THIS ESTF ISSUANCE. CONTINUING MENTION OF
PATCHY FOG IN FORECAST AS SPOTTY FOG SHOWING UP IN LATEST OBS.
LATEST RADAR LOOP SHOWING ISOLATED/SCATTERED RW/TRW ALONG PORTIONS
OF OUR CWA...SO HAVE LEFT IN CURRENT MENTION OF PRECIPITATION.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 215 AM MDT WED JUL 23 2014
SCATTERED THUNDERSTORMS ALONG NORTHERN BORDER ZONES THIS MORNING IN
CONNECTION WITH FRONTAL BOUNDARY...REMNANTS WHICH HAS BEEN
MEANDERING OVER KANSAS/NEBRASKA OVERNIGHT. MOST OF THE PRECIPITATION
WILL OCCUR OUT OF CWA...BUT HAVE INCLUDED SL CHANCE POPS FOR TRW
THRU 14Z-15Z FOR NORTHERN ZONES. HIGH DEWPTS AROUND THE AREA
CREATING MUGGY CONDITIONS WHICH COULD TRANSLATE INTO A FEW HOURS OF
PATCHY FOG THIS MORNING UNTIL SUNRISE SO HAVE MENTIONED FOR ALL
AREAS. MID/UPPER LEVEL RIDGE WILL RE-ASSERT ITSELF AGAIN ACROSS THE
CWA TODAY INTO TONIGHT. WITH THIS...EXPECTING YET ANOTHER HOT DAY
ACROSS THE AREA...WITH MID TO UPPER 90S FOR HIGHS...AND MID TO
UPPER 60S FOR OVERNIGHT LOWS. ONLY WESTERN ZONES WILL POTENTIALLY
SEE A LATE DAY REPRIEVE AS ISOLATED TRW MAY DEVELOP AS LEE-SIDE
TROUGH SETS UP ALONG EASTERN ROCKIES.
.LONG TERM...(THURSDAY THROUGH TUESDAY)
ISSUED AT 215 AM MDT WED JUL 23 2014
FOR THE THURSDAY THROUGH FRIDAY NIGHT PERIODS...THE CWA WILL
CONTINUE TO SEE MAINLY HOT AND DRY CONDITIONS AS BROAD H5/H7 RIDGE
REMAINS OVER THE AREA. DOWN TO THE SURFACE...LEE-SIDE TROUGH
DEVELOPS AND MOVES ACROSS THE REGION THURSDAY/THURSDAY NIGHT WITH A
WEAK SHORTWAVE WORKING OVER TOP OF RIDGE...AS MODELS DO SHOW SOME
FLATTENING POTENTIAL FRIDAY/FRIDAY NIGHT WHICH MAY BRING A CHANCE
FOR CONVECTION. WITH 925 MB TEMPERATURES REMAINING IN THE +35C TO
+40C...FORECASTED HIGHS WILL STAY IN THE 95-100 DEGREE RANGE FOR
BOTH DAYS. OVERNIGHT LOWS WILL STAY IN 60S...WARMEST IN EASTERN
ZONES. BOTH HIGHS/LOWS WILL BE AFFECTED AT TIMES FROM EXPECTED CLOUD
COVER/PRECIP...BUT WILL BE LOCALIZED AS WILL BE KEEPING SL CHANCE
POPS IN FOR TRW. BEST CHANCES FOR CONVECTION THURSDAY/THURSDAY NIGHT
WILL BE SPLIT DUE TO SLOW MOVEMENT OF TROUGH OFF THE ROCKIES...AND
FOR FRIDAY/FRIDAY NIGHT THE MAIN FOCUS WILL SHIFT TO NORTHERN
SECTIONS DUE TO TRACK OF SHORTWAVE.
COOLING TREND LATE THIS WEEKEND INTO NEXT WEEK WITH A FEW CHANCES
FOR PRECIP ALONG THE WAY. HAVE GENERALLY LOWERED POPS ACROSS THE
FORECAST PERIOD...BUT AM STILL CONFIDENT WE WILL SEE SOME CONVECTIVE
ACTIVITY MOST DAYS. UPPER FLOW WILL BE MAINLY OUT OF THE NORTHWEST
AS AN UPPER HIGH OVER THE FOUR CORNERS REGION RETROGRADES WEST A BIT
AND A RIDGE DEVELOPS ACROSS THE GREAT BASIN REGION EARLY NEXT WEEK.
COLD FRONT ARRIVING OVER THE WEEKEND WILL BRING RELATIVELY COOLER
TEMPS AND /THANKFULLY/ LOWER DEW POINTS.
SATURDAY...WEAK IMPULSES MOVING ACROSS THE COLORADO ROCKIES COULD
PROVIDE AMPLE LARGE SCALE LIFT FOR ISOLATED STORMS TO DEVELOP DURING
THE DAY. PREVIOUS GUIDANCE HAD INDICATED SUFFICIENT INSTABILITY FOR
STRONG TO SEVERE THUNDERSTORMS...BUT IT SEEMS THE ECMWF IS NOW
LEANING TOWARDS WHAT HAS RECENTLY BEEN A VERY DRY GFS. GEM REMAINS
STEADFAST IN SOME INSTABILITY DUE TO BETTER MOISTURE THROUGHOUT THE
COLUMN...SO WILL CONTINUE TO KEEP SOME POPS IN PLACE DESPITE THE DRY
GFS AND ECMWF. SATURDAY NIGHT IS A DIFFERENT STORY...WITH
GEFS/ECMWF/GEM INDICATING INCREASED MOISTURE AVAILABILITY AS COLD
FRONT PUSHES THROUGH FROM THE NORTH/NORTHWEST. THIS SHOULD SUPPORT
AT LEAST ISOLATED STORMS LATE IN THE DAY...POSSIBLY LASTING THROUGH
THE NIGHT. UPPER LEVEL SUPPORT FOR LARGE SCALE LIFT ACROSS THE
LATEST GUIDANCE IS NOT AS SUPPORTIVE ON LATEST GUIDANCE AS PREVIOUS
RUNS HAVE BEEN...SO A BIT LOWER CONFIDENCE THAN USUAL FOR OVERNIGHT
STORMS.
SUNDAY...COOLER FOLLOWING FROPA. SOME CLOUDS DURING THE MORNING
CLEARING OUT TO A MOSTLY SUNNY DAY. SOME AFTERNOON CONVECTION
POSSIBLE BEHIND THE FRONT...THOUGH THERE IS CHANCE THE MODERATELY
STRONG CAP COULD PREVENT DEVELOPMENT. GUIDANCE IN GOOD AGREEMENT ON
AN INVERTED-V SOUNDING...SO WITH ANY STORMS THAT DEVELOP GUSTY WINDS
COULD BE POSSIBLE. A FEW STORMS COULD LAST INTO THE EVENING...ENDING
BEFORE MIDNIGHT. HIGHS LIMITED TO THE MID/UPPER 80S. OVERNIGHT LOWS
DIPPING BELOW 60 IN SOME SPOTS FOR THE FIRST TIME IN A WEEK.
MONDAY AND TUESDAY...SLIGHT CHANCE FOR SHOWERS/STORMS BOTH
DAYS...WITH THE BETTER CHANCE FOR PRECIP ON TUESDAY. A NUMBER OF
WEAK MID-LEVEL IMPULSES WILL MOVE ACROSS THE CENTRAL ROCKIES AND
INTO THE CENTRAL HIGH PLAINS IN THE NORTH-NORTHWESTERLY FLOW. IN
THIS FAVORABLE ENVIRONMENT EXPECT MOSTLY TERRAIN-BASED STORMS TO
FIRE IN THE DAY AND MOVE EAST INTO THE AREA DURING THE LATE
AFTERNOON. LOW LEVEL FLOW WILL BE OUT OF THE SOUTH WHICH WILL
INCREASE LOW LEVEL MOISTURE...AND THUS PROVIDE SOME INSTABILITY FOR
STORMS TO WORK WITH. 0-6KM BULK SHEAR IN THE 30-40KT RANGE COULD
HELP SUSTAIN STORMS THROUGH THE LATE NIGHT HOURS. HIGHS IN THE
MID/UPPER 80S.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z THURSDAY MORNING)
ISSUED AT 523 AM MDT WED JUL 23 2014
FOR GLD/MCK THROUGH 14Z...MIX OF CONDITIONS FROM MVFR DOWN TO LIFR
WITH FOG 4-6SM AND CEILINGS RANGING FROM BKN004-010. AFT 14Z VFR
CONDITIONS WITH FEW020-030 SCT200-300. VCTS POSSIBLE FOR GLD 01Z-
06Z WITH SCT060CB. WINDS RANGE FROM ENE TO ESE 5-10KTS BECM SSE
10-20KTS BY 14Z.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
UPDATE...JRM
SHORT TERM...JN
LONG TERM...JJM
AVIATION...JN
AREA FORECAST DISCUSSION
NWS SHREVEPORT LA
555 PM CDT WED JUL 23 2014
.AVIATION...
WOW...JUST AMENDED KTXK...HOPE IT IS ENOUGH AS GUSTS TO 91KTS
COMING DOWN THE PIPE. A LARGE WIDESPREAD OPEN ENDED DERECHO IS
NEARLY ENTERING THE CITY LIMITS WITH WIDE SPREAD GUSTS OVER 60KTS.
OUR RADAR IS NOW IN THE PURPLE HAZE LAST SCAN. LOOK FOR MANY
TERMINALS TO BE EFFECTED THIS EVENING WITH MANY AMENDMENTS YET TO
COME EVEN IN THE NEW ISSUANCE. WE WILL MONITOR CLOSELY...BUT THE
NON AMENDMENTS PERIOD IS NEARLY UPON US. THE GOOD NEWS IS THAT
TOPS ARE WANNING NOW IN THE LATE AFTERNOON HEAT OF THE DAY. WHY
ALOFT WE ARE NE THROUGHOUT THE COLUMN...45KTS PEAK SO FAR AT KTXK.
/24/
&&
.PREV DISCUSSION... /ISSUED 340 PM CDT WED JUL 23 2014/
DISCUSSION...
SVR MCS ONGOING THIS AFTERNOON ACROSS ERN OK/WRN AND CNTRL
AR...WITH THE CNTRL AR CONVECTION EXPECTED TO MERGE INTO THE BOW
ECHO RIDING S ALONG THE OK/AR LINE. SBCAPES ARE VERY UNSTABLE THIS
AFTERNOON...WITH 4500-5000+ J/KG NOTED JUST S OF THIS
COMPLEX...WHERE STRONG HEATING AND LOW LEVEL MOISTURE POOLING
ALONG/JUST AHEAD OF A SFC TROUGH WHICH HAS BEEN CONVECTIVELY
REINFORCED OVER NRN/ERN OK INTO CNTRL AR. HAVE NOTICED A TREND OF
INCREASING INSTABILITY S OF THE RED RIVER ACROSS EXTREME NE TX/SW
AR...THUS HAVE ADDED SVR MENTION INTO THE FORECAST THIS EVENING AS
THIS MCS CONTINUES SWD BEFORE GRADUALLY WEAKENING WITH THE LOSS OF
HEATING. HOWEVER...ITS FORWARD MOMENTUM MAY KEEP THIS LINE
STRONG/POSSIBLY SVR PERHAPS AS FAR S AS I-30...IF NOT EVEN FARTHER
S TOWARDS TYR/GGG BEFORE DISSIPATING. THE HRRR INITIALIZED WELL
THIS MORNING ON THE SE KS CONVECTION AND REMAINS CONSISTENT
PROPAGATING THIS MCS SSWWD ACROSS NE TX/SW AR BEFORE
WEAKENING...ALTHOUGH PORTIONS OF EXTREME NW LA CAN/T BE RULED OUT
COMPLETELY.
AFTERWARDS...THE SFC TROUGH REMAINS PROGGED TO SLOWLY DRIFT S INTO
EXTREME SE OK/NRN SECTIONS OF SW AR BY 12Z THURSDAY...AND SLOWLY
BACKDOORING SW INTO N LA/NE TX BY AFTERNOON BEFORE BECOMING
STATIONARY. THIS REMAINS CONSISTENT WITH THE AFTERNOON PROGS
TUESDAY...WITH THIS BNDRY LIKELY CONTRIBUTING TO COMPRESSIONAL
WARMING NEAR AND S OF IT OVER NE TX/N LA. IT IS POSSIBLE THAT LOW
LEVEL MOISTURE POOLING COULD BE AN ISSUE ALONG THIS BNDRY AS HAS
BEEN THE CASE TODAY FARTHER N...WHICH COULD RESULT IN HEAT INDICES
NEAR 105 DEGREES THURSDAY AFTERNOON. BUT GIVEN THE UNCERTAINTY AS
TO THE EFFECT OF THE ONGOING CONVECTION WILL HAVE ON THE CURRENT
AIR MASS...HAVE OPTED NOT TO INCLUDE A HEAT ADVISORY FOR PORTIONS
OF THE REGION. AS HAS BEEN THE CASE TODAY...THE SFC TROUGH MAY
FOCUS SCT CONVECTION THURSDAY AFTERNOON MAINLY OVER PORTIONS OF
EXTREME ERN TX/N LA. DEPENDING ON THE EXTENT OF INSTABILITY
PRESENT GIVEN THE COMPRESSIONAL WARMING/POTENTIAL LOW LEVEL
MOISTURE POOLING...CAN/T RULE OUT AN ISOLATED SVR STORM
THREAT...ALTHOUGH THIS POTENTIAL MAY BE MINIMIZED GIVEN THE LACK
OF AN UPPER LEVEL FOCUS/SLIGHTLY WEAKER BULK SHEAR. HAVE
MAINTAINED LOW CHANCE POPS S OF THE TROUGH...WITH SLIGHT CHANCE
POPS NEAR AND N OF IT...WITH ANY CONVECTION EXPECTED TO WIND DOWN
THURSDAY EVENING WITH THE LOSS OF HEATING.
AFTERWARDS...THE UPPER LEVEL RIDGE CENTERED OVER THE FOUR CORNERS
REGION WILL EXPAND E ACROSS THE PLAINS INTO THE MS VALLEY...DIALING
UP THE HEAT AND ELIMINATING RAIN CHANCES FOR THE WEEKEND. MAX
TEMPS SHOULD NEAR THE CENTURY MARK ESPECIALLY OVER E TX THIS
WEEKEND...WITH THE RIDGE EXPECTED TO SLOWLY RETROGRADE BACK TO THE
W EARLY NEXT WEEK IN RESPONSE TO THE NEXT LONGWAVE TROUGH THAT
WILL DIG SE ACROSS THE NRN PLAINS AND MS VALLEY. THIS TROUGH WILL
EVENTUALLY HELP TO USHER IN ANOTHER UNUSUAL JULY COOL FRONT LATE
MONDAY THROUGH TUESDAY. HOWEVER...IT APPEARS MOISTURE AND UPPER
LEVEL FORCING WILL BE LIMITED WITH THIS FROPA...ALTHOUGH COOLER
AND DRIER AIR SHOULD SPILL SWD FOR THE MID AND LATE WEEK
TIMEFRAME. BOTH THE GFS AND ECMWF ARE CONSISTENT THOUGH IN THE
DEVELOPMENT OF A SHORTWAVE TROUGH OVER THE SRN PLAINS
WEDNESDAY...WHICH MAY RESULT IN SCT CONVECTION AFFECTING THE
REGION BY THE END OF THE EXTENDED. THESE COOLER TEMPS LOOK TO
LINGER AS WE ENTER AUGUST.
PRELIMS TO FOLLOW BELOW...
15
&&
.PRELIMINARY POINT TEMPS/POPS...
SHV 74 96 75 96 75 / 20 30 10 10 0
MLU 72 93 70 93 73 / 20 30 10 10 0
DEQ 72 93 70 96 72 / 40 20 10 10 0
TXK 73 94 70 95 74 / 40 20 10 10 0
ELD 72 93 68 93 72 / 30 20 10 10 0
TYR 74 97 76 98 76 / 30 20 10 10 0
GGG 73 95 75 96 75 / 30 20 10 10 0
LFK 74 97 75 97 75 / 20 20 20 10 0
&&
.SHV WATCHES/WARNINGS/ADVISORIES...
AR...NONE.
LA...NONE.
OK...NONE.
TX...NONE.
&&
$$
24/99/99
AREA FORECAST DISCUSSION
NWS SHREVEPORT LA
340 PM CDT WED JUL 23 2014
.DISCUSSION...
SVR MCS ONGOING THIS AFTERNOON ACROSS ERN OK/WRN AND CNTRL
AR...WITH THE CNTRL AR CONVECTION EXPECTED TO MERGE INTO THE BOW
ECHO RIDING S ALONG THE OK/AR LINE. SBCAPES ARE VERY UNSTABLE THIS
AFTERNOON...WITH 4500-5000+ J/KG NOTED JUST S OF THIS
COMPLEX...WHERE STRONG HEATING AND LOW LEVEL MOISTURE POOLING
ALONG/JUST AHEAD OF A SFC TROUGH WHICH HAS BEEN CONVECTIVELY
REINFORCED OVER NRN/ERN OK INTO CNTRL AR. HAVE NOTICED A TREND OF
INCREASING INSTABILITY S OF THE RED RIVER ACROSS EXTREME NE TX/SW
AR...THUS HAVE ADDED SVR MENTION INTO THE FORECAST THIS EVENING AS
THIS MCS CONTINUES SWD BEFORE GRADUALLY WEAKENING WITH THE LOSS OF
HEATING. HOWEVER...ITS FORWARD MOMENTUM MAY KEEP THIS LINE
STRONG/POSSIBLY SVR PERHAPS AS FAR S AS I-30...IF NOT EVEN FARTHER
S TOWARDS TYR/GGG BEFORE DISSIPATING. THE HRRR INITIALIZED WELL
THIS MORNING ON THE SE KS CONVECTION AND REMAINS CONSISTENT
PROPAGATING THIS MCS SSWWD ACROSS NE TX/SW AR BEFORE
WEAKENING...ALTHOUGH PORTIONS OF EXTREME NW LA CAN/T BE RULED OUT
COMPLETELY.
AFTERWARDS...THE SFC TROUGH REMAINS PROGGED TO SLOWLY DRIFT S INTO
EXTREME SE OK/NRN SECTIONS OF SW AR BY 12Z THURSDAY...AND SLOWLY
BACKDOORING SW INTO N LA/NE TX BY AFTERNOON BEFORE BECOMING
STATIONARY. THIS REMAINS CONSISTENT WITH THE AFTERNOON PROGS
TUESDAY...WITH THIS BNDRY LIKELY CONTRIBUTING TO COMPRESSIONAL
WARMING NEAR AND S OF IT OVER NE TX/N LA. IT IS POSSIBLE THAT LOW
LEVEL MOISTURE POOLING COULD BE AN ISSUE ALONG THIS BNDRY AS HAS
BEEN THE CASE TODAY FARTHER N...WHICH COULD RESULT IN HEAT INDICES
NEAR 105 DEGREES THURSDAY AFTERNOON. BUT GIVEN THE UNCERTAINTY AS
TO THE EFFECT OF THE ONGOING CONVECTION WILL HAVE ON THE CURRENT
AIR MASS...HAVE OPTED NOT TO INCLUDE A HEAT ADVISORY FOR PORTIONS
OF THE REGION. AS HAS BEEN THE CASE TODAY...THE SFC TROUGH MAY
FOCUS SCT CONVECTION THURSDAY AFTERNOON MAINLY OVER PORTIONS OF
EXTREME ERN TX/N LA. DEPENDING ON THE EXTENT OF INSTABILITY
PRESENT GIVEN THE COMPRESSIONAL WARMING/POTENTIAL LOW LEVEL
MOISTURE POOLING...CAN/T RULE OUT AN ISOLATED SVR STORM
THREAT...ALTHOUGH THIS POTENTIAL MAY BE MINIMIZED GIVEN THE LACK
OF AN UPPER LEVEL FOCUS/SLIGHTLY WEAKER BULK SHEAR. HAVE
MAINTAINED LOW CHANCE POPS S OF THE TROUGH...WITH SLIGHT CHANCE
POPS NEAR AND N OF IT...WITH ANY CONVECTION EXPECTED TO WIND DOWN
THURSDAY EVENING WITH THE LOSS OF HEATING.
AFTERWARDS...THE UPPER LEVEL RIDGE CENTERED OVER THE FOUR CORNERS
REGION WILL EXPAND E ACROSS THE PLAINS INTO THE MS VALLEY...DIALING
UP THE HEAT AND ELIMINATING RAIN CHANCES FOR THE WEEKEND. MAX
TEMPS SHOULD NEAR THE CENTURY MARK ESPECIALLY OVER E TX THIS
WEEKEND...WITH THE RIDGE EXPECTED TO SLOWLY RETROGRADE BACK TO THE
W EARLY NEXT WEEK IN RESPONSE TO THE NEXT LONGWAVE TROUGH THAT
WILL DIG SE ACROSS THE NRN PLAINS AND MS VALLEY. THIS TROUGH WILL
EVENTUALLY HELP TO USHER IN ANOTHER UNUSUAL JULY COOL FRONT LATE
MONDAY THROUGH TUESDAY. HOWEVER...IT APPEARS MOISTURE AND UPPER
LEVEL FORCING WILL BE LIMITED WITH THIS FROPA...ALTHOUGH COOLER
AND DRIER AIR SHOULD SPILL SWD FOR THE MID AND LATE WEEK
TIMEFRAME. BOTH THE GFS AND ECMWF ARE CONSISTENT THOUGH IN THE
DEVELOPMENT OF A SHORTWAVE TROUGH OVER THE SRN PLAINS
WEDNESDAY...WHICH MAY RESULT IN SCT CONVECTION AFFECTING THE
REGION BY THE END OF THE EXTENDED. THESE COOLER TEMPS LOOK TO
LINGER AS WE ENTER AUGUST.
PRELIMS TO FOLLOW BELOW...
15
&&
.PRELIMINARY POINT TEMPS/POPS...
SHV 74 96 75 96 75 / 20 30 10 10 0
MLU 72 93 70 93 73 / 20 30 10 10 0
DEQ 72 93 70 96 72 / 40 20 10 10 0
TXK 73 94 70 95 74 / 40 20 10 10 0
ELD 72 93 68 93 72 / 30 20 10 10 0
TYR 74 97 76 98 76 / 30 20 10 10 0
GGG 73 95 75 96 75 / 30 20 10 10 0
LFK 74 97 75 97 75 / 20 20 20 10 0
&&
.SHV WATCHES/WARNINGS/ADVISORIES...
AR...NONE.
LA...NONE.
OK...NONE.
TX...NONE.
&&
$$
15
AREA FORECAST DISCUSSION...UPDATED
NWS SHREVEPORT LA
112 PM CDT WED JUL 23 2014
.UPDATE...
ZONE UPDATE JUST SENT TO INCLUDE SVR WATCH 431 FOR MCCURTAIN
COUNTY OK AS WELL AS LITTLE RIVER/SEVIER/HOWARD COUNTIES IN SW AR
THROUGH 01Z. SEE PREVIOUS DISCUSSION BELOW ISSUED AT 1137 AM FOR
REASONING.
15
&&
.AVIATION...
VFR FLIGHT CONDITIONS PERSIST ACROSS THE ARKLATEX THIS
AFTERNOON...AND THIS WILL LIKELY CONTINUE TO PREVAIL IN AREA TAFS.
SOME SCATTERED TSRA ACTIVITY MAY BE OBSERVED BETWEEN 20Z AND 01Z
ALONG AND NORTH OF THE I30 CORRIDOR...SO WE MAY HAVE TO AMD TXK FOR
THUNDERSTORMS IF THEY DEVELOP. OTHERWISE LIGHT WINDS AND VFR
CONDITIONS WILL PERSIST THROUGH THE 18Z TAF PERIOD. /11/
&&
.PREV DISCUSSION... /ISSUED 1137 AM CDT WED JUL 23 2014/
DISCUSSION...
AM EYEING TWO FEATURES THIS MORNING...ONE IS THE UPPER LOW CENTERED
OVER SE LA...AND THE SECOND IS A WEAK TROUGH AXIS SLIDING SWD ACROSS
THE MID MS VALLEY. THE SHORT TERM PROGS ARE IN GOOD AGREEMENT KEEPING
THE UPPER LOW STATIONARY THROUGH THE AFTERNOON...WITH SCT CONVECTION
EXPECTED TO FIRE BY AFTERNOON ON THE NW PERIPHERY OF THE
LOW...AFFECTING PRIMARILY THE SE SECTIONS OF NCNTRL LA. ALREADY SEEING
SOME LIGHT ELEVATED RADAR RETURNS NOW ALONG AND E OF THE MS
RIVER...WITH THIS CONVECTION EXPECTED TO SPREAD SW THROUGH THE
AFTERNOON. HOWEVER...PRIMARY FOCUS IS FARTHER TO THE N...WHERE THE
TROUGH AXIS SHOULD SHEAR SW INTO CNTRL AR AND POSSIBLY EXTREME SE
OK/NE TX THIS AFTERNOON. MOSAIC RADAR INDICATES ISOLATED CONVECTION
DEVELOPING JUST W OF LIT...JUST AHEAD OF A WEAK SFC TROUGH OVER NE OK
INTO NRN AR...IN VC OF THIS SHEARING TROUGH. THE WRF AND HRRR ARE
AGGRESSIVE IN DEVELOPING SCT CONVECTION BY EARLY/MID AFTERNOON OVER
WRN AR/SE OK...AND SLIDING SW AROUND THE PERIPHERY OF THE UPPER RIDGE
INTO EXTREME NE TX. IN ADDITION...THE SMALL COMPLEX OF CONVECTION
OVER SE KS COULD ACTUALLY PLAY A ROLE IN INTENSIFYING CONVECTION
THIS AFTERNOON OVER SE OK/WRN AR AS IT COULD BECOME ABSORBED INTO
THE CONVECTION FARTHER E...BEFORE ACCELERATING SW. DON/T BELIEVE THE
SFC TROUGH WILL MAKE MUCH PROGRESS S DURING THE AFTERNOON UNLESS
BEING REINFORCED SWD FROM THE STORMS...WITH CONVECTION BECOMING
OUTFLOW DOMINANT AND RIDING THE MEAN FLOW AS IT FOLLOWS THE BETTER
INSTABILITY OVER THE NRN ZONES. GIVEN THE MODERATE/STRONG
INSTABILITY IN PLACE OVER ERN OK/WRN AR WHERE LOW LEVEL MOISTURE
POOLING IS IN PLACE NEAR THE SFC TROUGH /WITH TEMPS HAVING ALREADY
REACHED NEAR 90 ALREADY/...CAN/T RULE OUT A SMALL COMPLEX OF SVR
CONVECTION DEVELOPING AND AFFECTING AREAS ALONG/N OF THE I-30
CORRIDOR. A CAVEAT THOUGH WOULD BE THE SWWD EXTENT OF THE CONVECTION
LATE THIS AFTERNOON...AS IT COULD ENCOUNTER LESS INSTABILITY
/THROUGH SUFFICIENT MIXING/ AS IT REACHES THE I-30 CORRIDOR OF NE TX
AND BECOMES MORE REMOVED FROM THE SHEAR AXIS ALOFT.
HAVE INCREASED POPS TO MID CHANCE THIS AFTERNOON FOR EXTREME NE TX/SE
OK/SW AR...WHILE ALSO EXPANDING SLIGHT CHANCE POPS TO COVER THE I-20
CORRIDOR OF E TX/N LA IN CASE THIS CONVECTION DOES MATERIALIZE AND
SENDS OUTFLOW BNDRYS SWD. 16Z TEMPS HAVE ALSO QUICKLY CLIMBED TO THE
MID/UPPER 80S...AND HAVE BUMPED MAX TEMPS UP A DEGREE OR TWO
ESPECIALLY OVER NE TX/NW LA. OTHERWISE...THE REMAINDER OF THE FORECAST
IS ON TRACK.
15
&&
.PRELIMINARY POINT TEMPS/POPS...
SHV 94 72 95 72 96 / 20 20 20 10 10
MLU 93 71 93 69 93 / 20 20 20 20 10
DEQ 92 70 94 68 95 / 40 30 0 10 0
TXK 93 72 94 70 95 / 40 30 10 10 0
ELD 93 71 93 69 94 / 20 20 20 10 0
TYR 95 74 97 75 97 / 20 20 20 10 0
GGG 94 73 96 74 97 / 20 20 20 10 0
LFK 95 74 95 76 96 / 30 20 30 20 10
&&
.SHV WATCHES/WARNINGS/ADVISORIES...
AR...NONE.
LA...NONE.
OK...NONE.
TX...NONE.
&&
$$
15
AREA FORECAST DISCUSSION...UPDATED
NWS SHREVEPORT LA
1137 AM CDT WED JUL 23 2014
.DISCUSSION...
AM EYEING TWO FEATURES THIS MORNING...ONE IS THE UPPER LOW CENTERED
OVER SE LA...AND THE SECOND IS A WEAK TROUGH AXIS SLIDING SWD ACROSS
THE MID MS VALLEY. THE SHORT TERM PROGS ARE IN GOOD AGREEMENT KEEPING
THE UPPER LOW STATIONARY THROUGH THE AFTERNOON...WITH SCT CONVECTION
EXPECTED TO FIRE BY AFTERNOON ON THE NW PERIPHERY OF THE
LOW...AFFECTING PRIMARILY THE SE SECTIONS OF NCNTRL LA. ALREADY SEEING
SOME LIGHT ELEVATED RADAR RETURNS NOW ALONG AND E OF THE MS
RIVER...WITH THIS CONVECTION EXPECTED TO SPREAD SW THROUGH THE
AFTERNOON. HOWEVER...PRIMARY FOCUS IS FARTHER TO THE N...WHERE THE
TROUGH AXIS SHOULD SHEAR SW INTO CNTRL AR AND POSSIBLY EXTREME SE
OK/NE TX THIS AFTERNOON. MOSAIC RADAR INDICATES ISOLATED CONVECTION
DEVELOPING JUST W OF LIT...JUST AHEAD OF A WEAK SFC TROUGH OVER NE OK
INTO NRN AR...IN VC OF THIS SHEARING TROUGH. THE WRF AND HRRR ARE
AGGRESSIVE IN DEVELOPING SCT CONVECTION BY EARLY/MID AFTERNOON OVER
WRN AR/SE OK...AND SLIDING SW AROUND THE PERIPHERY OF THE UPPER RIDGE
INTO EXTREME NE TX. IN ADDITION...THE SMALL COMPLEX OF CONVECTION
OVER SE KS COULD ACTUALLY PLAY A ROLE IN INTENSIFYING CONVECTION
THIS AFTERNOON OVER SE OK/WRN AR AS IT COULD BECOME ABSORBED INTO
THE CONVECTION FARTHER E...BEFORE ACCELERATING SW. DON/T BELIEVE THE
SFC TROUGH WILL MAKE MUCH PROGRESS S DURING THE AFTERNOON UNLESS
BEING REINFORCED SWD FROM THE STORMS...WITH CONVECTION BECOMING
OUTFLOW DOMINANT AND RIDING THE MEAN FLOW AS IT FOLLOWS THE BETTER
INSTABILITY OVER THE NRN ZONES. GIVEN THE MODERATE/STRONG
INSTABILITY IN PLACE OVER ERN OK/WRN AR WHERE LOW LEVEL MOISTURE
POOLING IS IN PLACE NEAR THE SFC TROUGH /WITH TEMPS HAVING ALREADY
REACHED NEAR 90 ALREADY/...CAN/T RULE OUT A SMALL COMPLEX OF SVR
CONVECTION DEVELOPING AND AFFECTING AREAS ALONG/N OF THE I-30
CORRIDOR. A CAVEAT THOUGH WOULD BE THE SWWD EXTENT OF THE CONVECTION
LATE THIS AFTERNOON...AS IT COULD ENCOUNTER LESS INSTABILITY
/THROUGH SUFFICIENT MIXING/ AS IT REACHES THE I-30 CORRIDOR OF NE TX
AND BECOMES MORE REMOVED FROM THE SHEAR AXIS ALOFT.
HAVE INCREASED POPS TO MID CHANCE THIS AFTERNOON FOR EXTREME NE TX/SE
OK/SW AR...WHILE ALSO EXPANDING SLIGHT CHANCE POPS TO COVER THE I-20
CORRIDOR OF E TX/N LA IN CASE THIS CONVECTION DOES MATERIALIZE AND
SENDS OUTFLOW BNDRYS SWD. 16Z TEMPS HAVE ALSO QUICKLY CLIMBED TO THE
MID/UPPER 80S...AND HAVE BUMPED MAX TEMPS UP A DEGREE OR TWO
ESPECIALLY OVER NE TX/NW LA. OTHERWISE...THE REMAINDER OF THE FORECAST
IS ON TRACK.
15
&&
.PRELIMINARY POINT TEMPS/POPS...
SHV 94 72 95 72 96 / 20 20 20 10 10
MLU 93 71 93 69 93 / 20 20 20 20 10
DEQ 92 70 94 68 95 / 40 30 0 10 0
TXK 93 72 94 70 95 / 40 30 10 10 0
ELD 93 71 93 69 94 / 20 20 20 10 0
TYR 95 74 97 75 97 / 20 20 20 10 0
GGG 94 73 96 74 97 / 20 20 20 10 0
LFK 95 74 95 76 96 / 30 20 30 20 10
&&
.SHV WATCHES/WARNINGS/ADVISORIES...
AR...NONE.
LA...NONE.
OK...NONE.
TX...NONE.
&&
$$
15
AREA FORECAST DISCUSSION
NWS SHREVEPORT LA
1123 AM CDT WED JUL 23 2014
.DISCUSSION...
AM EYEING TWO FEATURES THIS MORNING...ONE IS THE UPPER LOW CENTERED
OVER SE LA...AND THE SECOND IS A WEAK TROUGH AXIS SLIDING SWD ACROSS
THE MID MS VALLEY. THE SHORT TERM PROGS ARE IN GOOD AGREEMENT KEEPING
THE UPPER LOW STATIONARY THROUGH THE AFTERNOON...WITH SCT CONVECTION
EXPECTED TO FIRE BY AFTERNOON ON THE NW PERIPHERY OF THE
LOW...AFFECTING PRIMARILY THE SE SECTIONS OF NCNTRL LA. ALREADY SEEING
SOME LIGHT ELEVATED RADAR RETURNS NOW ALONG AND E OF THE MS
RIVER...WITH THIS CONVECTION EXPECTED TO SPREAD SW THROUGH THE
AFTERNOON. HOWEVER...PRIMARY FOCUS IS FARTHER TO THE N...WHERE THE
TROUGH AXIS SHOULD SHEAR SW INTO CNTRL AR AND POSSIBLY EXTREME SE
OK/NE TX THIS AFTERNOON. MOSAIC RADAR INDICATES ISOLATED CONVECTION
DEVELOPING JUST W OF LIT...JUST AHEAD OF A WEAK SFC TROUGH OVER NE OK
INTO NRN AR...IN VC OF THIS SHEARING TROUGH. THE WRF AND HRRR ARE
AGGRESSIVE IN DEVELOPING SCT CONVECTION BY EARLY/MID AFTERNOON OVER
WRN AR/SE OK...AND SLIDING SW AROUND THE PERIPHERY OF THE UPPER RIDGE
INTO EXTREME NE TX. DON/T BELIEVE THE SFC TROUGH WILL MAKE MUCH
PROGRESS S DURING THE AFTERNOON...WITH CONVECTION BECOMING OUTFLOW
DOMINANT AND RIDING THE MEAN FLOW AS IT FOLLOWS THE BETTER INSTABILITY
OVER THE NRN ZONES. A CAVEAT THOUGH WOULD BE THE SWWD EXTENT OF THE
CONVECTION LATE THIS AFTERNOON...AS IT COULD ENCOUNTER LESS
INSTABILITY /THROUGH SUFFICIENT MIXING/ AS IT REACHES THE I-30
CORRIDOR OF NE TX AND BECOMES MORE REMOVED FROM THE SHEAR AXIS ALOFT.
HAVE INCREASED POPS TO MID CHANCE THIS AFTERNOON FOR EXTREME NE TX/SE
OK/SW AR...WHILE ALSO EXPANDING SLIGHT CHANCE POPS TO COVER THE I-20
CORRIDOR OF E TX/N LA IN CASE THIS CONVECTION DOES MATERIALIZE AND
SENDS OUTFLOW BNDRYS SWD. 16Z TEMPS HAVE ALSO QUICKLY CLIMBED TO THE
MID/UPPER 80S...AND HAVE BUMPED MAX TEMPS UP A DEGREE OR TWO
ESPECIALLY OVER NE TX/NW LA. OTHERWISE...THE REMAINDER OF THE FORECAST
IS ON TRACK.
15
&&
.PRELIMINARY POINT TEMPS/POPS...
SHV 94 72 95 72 96 / 20 20 20 10 10
MLU 93 71 93 69 93 / 20 20 20 20 10
DEQ 92 70 94 68 95 / 40 30 0 10 0
TXK 93 72 94 70 95 / 40 30 10 10 0
ELD 93 71 93 69 94 / 20 20 20 10 0
TYR 95 74 97 75 97 / 20 20 20 10 0
GGG 94 73 96 74 97 / 20 20 20 10 0
LFK 95 74 95 76 96 / 30 20 30 20 10
&&
.SHV WATCHES/WARNINGS/ADVISORIES...
AR...NONE.
LA...NONE.
OK...NONE.
TX...NONE.
&&
$$
15
AREA FORECAST DISCUSSION...UPDATED
NWS GRAY ME
449 PM EDT WED JUL 23 2014
.SYNOPSIS...
A COLD FRONT WILL MOVE ACROSS THE REGION TONIGHT AND EXITS
OFFSHORE THURSDAY MORNING. HIGH PRESSURE BUILDS IN FROM THE WEST
FRIDAY AND SATURDAY. WET WEATHER WILL ONCE AGAIN BE POSSIBLE LATE
IN THE WEEKEND AND EARLY NEXT WEEK AS THE NEXT UPPER TROUGH DIVES
IN.
&&
.NEAR TERM /UNTIL 6 AM THURSDAY MORNING/...
.UPDATE..
SEVERE THUNDERSTORM WATCH CONTINUES FOR THE ENTIRE AREA THROUGH 10
PM. LINE OF STRONG STORMS ARE NOW MOVING SLOWLY SE THROUGH NH AND
MAINE. AREA OF OUTFLOW NOW MOVING AHEAD OF THE STORMS IN OXFORD
AND CARROLL COUNTIES MAY EVENTUALLY INTERACT WITH THE SEABREEZE IN
ANDROSCOGGIN/ CUMBERLAND COUNTIES. STRONGER/ SEVERE STORMS ARE
LOCATED IN VT AND MAY MOVE INTO NH IN THE NEXT HOUR OR TWO.
ADDITIONAL DEVELOPMENT ALONG A PRE FRONTAL TROUGH IS SUGGESTED BY
THE HRRR MODEL AHEAD OF THE CURRENT LINE OF STORMS. SO FAR THE LACK
OF MOISTURE AT 700MB IS LIKELY THE REASON FOR STORMS NOT REALIZING
THEIR FULL POTENTIAL TODAY...SOMETHING TO BE THANKFUL FOR. SHOULD
BE ABLE TO DROP THE NORTHERN COUNTIES FROM THE WATCH SHORTLY.
ADJUSTED POPS...MAX TEMPERATURE...DEW POINTS...AND WEATHER GRIDS
FOR THIS UPDATE.
&&
PREVIOUS DISCUSSION...
SEVERE THUNDERSTORM WATCH IN EFFECT FOR THE ENTIRE CWA UNTIL 10
PM. THUNDERSTORMS ACROSS FAR NORTHERN ZONES AS WELL AS VT ARE
EXPECTED TO CONTINUE TO DEVELOP AND MOVE FURTHER INTO THE CWA BY
EARLY EVENING. THE MAIN THREAT WILL BE DAMAGING WINDS AND
LOCALIZED FLASH FLOODING. THE CONVECTION SHOULD WEAKEN LATE THIS
EVENING WITH SHOWERS LINGERING FOR THE BALANCE OF THE NIGHT.
&&
.SHORT TERM /6 AM THURSDAY MORNING THROUGH THURSDAY NIGHT/...
LINGERING SHOWERS ACROSS S AND SE ZONES THROUGH MIDDAY THURS OR
SO...THEN SOME CLEARING TAKES PLACE. A FAIR NIGHT IS IN STORE FOR
THURS NIGHT AS HIGH PRESSURE BUILDS IN.
&&
.LONG TERM /FRIDAY THROUGH WEDNESDAY/...
A SLOW MOVING LOW PRESSURE SYSTEM WILL AFFECT THE AREA LATER IN
THE WEEKEND INTO EARLY NEXT WEEK WITH OCCASIONAL SHOWERS AND
POSSIBLY SOME THUNDERSTORMS.
&&
.AVIATION /21Z WEDNESDAY THROUGH MONDAY/...
SHORT TERM /THROUGH THURSDAY/...IFR OR LOWER IN SHOWERS AND
THUNDERSTORMS THROUGH THIS EVENING...THEN IMPROVING CONDITIONS ARE
FORESEEN. MAINLY VFR THU NIGHT AND FRI.
LONG TERM /THURSDAY NIGHT THROUGH SUNDAY/...IFR CONDITIONS WITH
SCT SHRA/TSTMS LIKELY TO DEVELOP SATURDAY NGT AND SUNDAY.
&&
.MARINE...
SHORT TERM /THROUGH FRIDAY/...SCA FOR TONIGHT FOR THE OCEAN WATERS FOR
MARGINAL 25 KT GUSTS AND SEAS 4-6 FT. QUIETER WINDS AND SEAS THU
THROUGH FRI.
LONG TERM /FRIDAY THROUGH MONDAY/...WINDS AND SEAS BELOW SCA
LEVELS THRU SATURDAY MORNING THEN SOUTHERLY FLOW INCREASES
POSSIBLY PUSHING WINDS AND SEAS TO SCA LEVELS OVER THE OPEN WATERS
LATE SATURDAY THRU SUNDAY.
&&
.GYX WATCHES/WARNINGS/ADVISORIES...
ME...NONE.
NH...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 6 AM EDT THURSDAY FOR ANZ150-152-
154.
&&
$$
UPDATE...HANES
AREA FORECAST DISCUSSION
NWS TWIN CITIES/CHANHASSEN MN
1206 PM CDT WED JUL 23 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 338 AM CDT WED JUL 23 2014
MOST IMPRESSIVE FEATURE ON THE H5 CHART LAST NIGHT WAS THE RIDGE
CENTERED OVER COLORADO...WHERE THE H5 HEIGHT MEASURED AT GRAND
JUNCTION REACHED THE LOFTY HEIGHT OF 6000 M. ITS ASSOCIATED RIDGE
AXIS EXTENDS NORTH INTO SASKATCHEWAN...WITH CONVERGENT NW FLOW NOTED
FROM MANITOBA INTO NW MN...HENCE THE 1028 MB SFC HIGH THAT IS
CENTERED OVER THE MANITOBA LAKES THIS MORNING. DURING THE SHORT
TERM...THE UPPER RIDGE WILL SHIFT EAST INTO THE UPPER MISS VALLEY
WHILE THE SFC HIGH WILL SHIFT OVER TO LAKE MICHIGAN BY 12Z THU.
FOR TODAY...NAM CU RULE SHOWS SCT-BKN CU FIELD DEVELOPING ACROSS WRN
WI...TRAILING OFF TO LITTLE IF ANY CU FOR WRN MN. HOWEVER...WRN MN
WILL HAVE TO DEAL WITH REMNANT CLOUD COVER FROM UPPER WAVES ROTATING
AROUND THE COLORADO RIDGE. IN PARTICULAR...THE RAP SHOWS THE WAVE
CURRENTLY OVER CENTRAL NODAK WORKING TOWARD WRN MN BY THE AFTERNOON.
DRY LOW LEVELS COURTESY THE 1028 MB HIGH WILL MAKE IT TOUGH TO GET
THE PRECIP IN THE MINOT AREA INTO MN...THOUGH A FEW SPRINKLES CAN
NOT BE COMPLETELY RULED OUT. DID BOOST SKY COVER WEST TO ACCOUNT FOR
THIS WAVE AND ITS ASSOCIATED CLOUD COVER THOUGH. H85 TEMPS WILL BE
FAIRLY UNIFORM AROUND 12/13C...WHICH HAS BEEN PRETTY GOOD THIS
SUMMER AT PRODUCING HIGHS IN THE 77 TO 81 DEGREE RANGE...SO NO BIG
CHANGES WERE NEEDED TO THE GOING FORECAST.
TONIGHT...AS THE RIDGE WORKS ACROSS WI...RETURN FLOW WILL BE
STRENGTHENING ACROSS THE DAKOTAS...WITH ISENTROPIC LIFT AND THETA-E
ADVECTION BOTH BLOSSOMING. LLJ ORIENTATION FAVORS ACTIVITY
DEVELOPING ALONG THE MO RIVER TONIGHT...MAKING ABOUT AS FAR EAST AS
SE SODAK...SO KEPT THE FORECAST DRY THROUGH 12Z THU...THOUGH WE
PROBABLY WILL NOT HAVE TO WAIT VERY LONG ON THU TO START SEEING
PRECIP PUSH INTO THE UPPER MN VALLEY. OVER WI...WITH THE HIGH
OVERHEAD THE QUESTION BECOMES HOW LOW TO GO...ALONG WITH THE
POTENTIAL FOR FOG. DID NUDGE LOWS DOWN A DEGREE OR TWO CLOSER TO THE
CONSENSUS RAW MODEL BLEND /BEST PERFORMING GUIDANCE OVER THE LAST
WEEK/...WHICH HAS LADYSMITH DIPPING INTO THE UPPER 40S. THE FOG
POTENTIAL IS A BIT TOUGHER TO PIN DOWN AT THIS POINT...BUT CERTAINLY
IF WE DO SEE LOWS DOWN AROUND 50...SOME PATCHY FOG...ESPECIALLY NEAR
BODIES OF WATER WILL CERTAINLY BE POSSIBLE.
.LONG TERM...(THURSDAY THROUGH TUESDAY)
ISSUED AT 338 AM CDT WED JUL 23 2014
SCATTERED SHOWERS AND THUNDERSTORMS ARE EXPECTED TO BE OVER
EASTERN DAKOTAS AT DAYBREAK ON THURSDAY ALONG AND AHEAD OF A
STRENGTHENING BAROCLINIC ZONE STRETCHING NW-SE ACROSS THE NORTHERN
PLAINS. THE SHOWERS AND THUNDERSTORMS WILL SPREAD ACROSS THE MN
CWA DURING THE DAY AND INTO WESTERN WI BY EVENING AS THE
FRONTOGENETIC ZONE MOVES EAST. THE FA IS IN THE RIGHT ENTRANCE REGION
OF AN 80 PLUS KNOT JET SEGMENT ACROSS THE WESTERN GREAT LAKES
WITH UPPER LEVEL DIVERGENCE INDICATED. BY THE END OF THE DAY...A
COUPLED JET STRUCTURE BEGINS TO DEVELOP...ALONG WITH INCREASING
DIVERGENCE...AS THE LEFT EXIT REGION OF A NEW SEGMENT ARRIVES FROM
THE EASTERN DAKOTAS. THIS FEATURE THEN PASSES ACROSS SOUTHERN
AREAS OF MN AND IA THURSDAY NIGHT. WHILE THIS IS OCCURRING...LOW
LEVEL MOISTURE TRANSPORT IN THE CENTRAL PLAINS VEERS INTO IA AND
SOUTHERN MN. THIS SHOULD RESULT IN THUNDERSTORMS INCREASING IN
COVERAGE ACROSS THE AFOREMENTIONED AREAS ALONG WITH THE POTENTIAL
FOR HEAVY RAIN. THE ECMWF HAS A GREAT HANDLE ON THIS SITUATION
WHILE OTHER DETERMINISTIC MODELS STRUGGLE TO DEVELOP MUCH
PRECIPITATION...WHICH IS A CHARACTERISTIC OF WARM AIR ADVECTION
EVENTS. HENCE...CHANCE POPS DURING THE DAY THURSDAY INCREASE TO
LIKELY THURSDAY NIGHT ACROSS SOUTHERN AREAS OF MN.
THE PRECIPITATION WILL MOVE ESE FRIDAY MORNING WITH A DRYING TREND
FRIDAY AFTERNOON AS A FAIRLY STRONG SHORT WAVE MOVES THROUGH.
HOWEVER...A WEAK SURFACE FRONT WILL SLOWLY TRAVERSE THE FA FRIDAY
AFTERNOON AND NIGHT WITH SOME SMALL POPS REMAINING. MUCH OF
SATURDAY LOOKS DRY BEFORE A COMPACT VERTICALLY STACKED LOW
PRESSURE SYSTEM SWINGS SOUTHEAST ACROSS THE UPPER MISSISSIPPI
VALLEY REGION SATURDAY NIGHT AND SUNDAY. THIS NECESSITATES MORE
CHANCE POPS FOR THE LATTER HALF OF THE WEEKEND. HIGHS FROM
THURSDAY TO SATURDAY WILL BE SLOWLY RISING FROM AROUND 80 TO THE
LOWER AND MIDDLE 80S RESPECTIVELY. HIGHS WILL THEN TREND DOWN INTO
THE MIDDLE TO UPPER 70S FOR SUNDAY AND AT LEAST THE FIRST HALF OF
NEXT WEEK. THE REASON FOR THE EXTENDED COOL DOWN IS A DEEPENING
EASTERN NORTH AMERICA TROUGH WITH A BUILDING RIDGE IN THE WEST.
LONGER RANGE MODEL SOLUTIONS HAVE BEEN VERY CONSISTENT ON THIS
DEVELOPMENT WITH A H5 CLOSED LOW JUST NORTH OF THE GREAT LAKES
NEXT WEDNESDAY. H5 HEIGHTS ACROSS THE GREAT LAKES AND OHIO VALLEY
ARE FORECAST TO BE 2 TO 3 STANDARD DEVIATIONS BELOW NORMAL.
ACCOMPANYING THE COOLER TEMPERATURES WILL BE MAINLY DRY CONDITIONS.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z THURSDAY AFTERNOON)
ISSUED AT 1157 AM CDT WED JUL 23 2014
OUTSIDE OF COMMON CLEAR SKIES - LIGHT WIND FOG AT KSTC/KRNH/KEAU
TOMORROW MORNING FOR A A COUPLE HOURS...LOOK FOR VFR CONDITIONS
AND AN OVERALL DRY SET OF TAFS. WE DO EXPECT A BATCH OF SHOWERS
AND WEAK THUNDERSTORMS TO FORM IN THE EASTERN DAKOTAS AND MOVE
INTO WEST CENTRAL AND SOUTHWEST MN TOMORROW MORNING...BUT MOST OF
THE ACTIVITY SHOULD STAY WEST OF THE TAF SITES. THE EXCEPTION
COULD BE KRWF...WHICH APPEARS CLOSE ENOUGH TO GET SOME RAIN. IT
APPEARS THE ACTIVITY WILL REMAIN FARTHER WEST THAN PREVIOUS
THOUGH...BUT LATER SHIFTS WILL MONITOR THE EASTERN EXTEND OF THE
RAIN AND ADD IT TO SITES IF NEEDED. THURSDAY NIGHT LOOKS A LITTLE
BETTER FOR RAIN AT THE REST OF THE MINNESOTA TAF SITES.
KMSP...
NO AVIATION WEATHER CONCERNS IN THE SHORT TERM WITH CLOUDS THAT
HAVE VFR BASES. WE`LL HAVE TO KEEP AN EYE OUT FOR THE THURSDAY
EVENING COMMUTE IF SOME OF THE THUNDERSTORMS THAT ARE LIKELY IN
WESTERN MN START TO TRANSLATE FARTHER EAST THAN EXPECTED.
/OUTLOOK FOR KMSP/
THU NIGHT...VFR. CHANCE MVFR CONDS W/ TSRA OVERNIGHT. WINDS SE AT
10KTS.
FRI...VFR. CHANCE TSRA. WINDS SSE AT 5-10KTS.
SAT...VFR. WINDS W AT 10KTS.
&&
.MPX WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...NONE.
&&
$$
SHORT TERM...MPG
LONG TERM...RAH
AVIATION...CLF
AREA FORECAST DISCUSSION
NWS BISMARCK ND
540 PM CDT WED JUL 23 2014
.UPDATE...
ISSUED AT 539 PM CDT WED JUL 23 2014
NO SIGNIFICANT CHANGES WITH THIS FORECAST UPDATE. STILL MONITORING
FOR CONVECTIVE INITIATION ACROSS CENTRAL INTO EASTERN MONTANA OVER
THE NEXT ONE TO TWO HOURS. THE 20 UTC HRRR WOULD SUGGEST
MONTANA SURFACE BASED CONVECTION APPROACHING THE NORTH DAKOTA BORDER
BY 03-04 UTC...CONTINUING TO PROPAGATE INTO CENTRAL NORTH DAKOTA
BY 08-09 UTC SUSTAINED BY A 30-35 KT LOW LEVEL JET. THE BEST
CHANCE FOR LARGE HAIL AND DAMAGING WINDS ARE GENERALLY ALONG AND
WEST OF HIGHWAY 85 AS THE MONTANA CONVECTION PROPAGATES INTO
WESTERN NORTH DAKOTA.
&&
.SHORT TERM...(THIS EVENING THROUGH THURSDAY)
ISSUED AT 320 PM CDT WED JUL 23 2014
FORECAST ISSUES IN THE SHORT TERM ARE THUNDERSTORM CHANCES...AND
POSSIBILITY OF SEVERE STORMS.
CURRENTLY...SURFACE HIGH WAS OVER MANITOBA SOUTHWARD THROUGH THE RED
RIVER VALLEY...WITH LOW PRESSURE IN THE LEE OF THE ROCKIES.
SOUTHEASTERLY FLOW WAS KEEPING MOIST LOW LEVELS WITH DEWPOINTS IN
THE 60S OVER WESTERN AND CENTRAL NORTH DAKOTA. AT UPPER LEVELS...A
SHARP RIDGE WAS IN PLACE FROM SASKATCHEWAN TO THE WESTERN DAKOTAS
AND EASTERN MT/WY. BEST SHEAR AND MID LEVEL LAPSE RATES WERE OVER
THE FRONT RANGE THIS AFTERNOON...WITH MOST UNSTABLE CAPES OVER THE
FRONT RANGE INTO THE WESTERN DAKOTAS.
LATEST MODEL RUNS SUGGEST THUNDERSTORMS DEVELOPING OVER CENTRAL AND
EASTERN MONTANA THIS EVENING IN THE VICINITY OF A MID LEVEL
SHORTWAVE ENERGY IMPULSE FORECAST TO MOVE/DEVELOP INTO NORTHEASTERN
MONTANA DURING THE EVENING. ONCE CONVECTION BECOMES BETTER
ESTABLISHED...THE SCENARIO IS FOR STORMS TO MIGRATE EASTWARD INTO
WESTERN NORTH DAKOTA LATER THIS EVENING...THEN SPREAD INTO CENTRAL
NORTH DAKOTA AFTER MIDNIGHT. THE WESTERN THIRD OF NORTH DAKOTA HAS
THE BEST POTENTIAL FOR SEVERE STORMS LATE THIS EVENING INTO THE
EARLY MORNING HOURS.
ONGOING CONVECTION DAYBREAK THURSDAY OVER MUCH OF CENTRAL NORTH
DAKOTA EXPECTED TO CONTINUE MOVING EASTWARD. THEN...ATTENTION TURNS
TO THE WEST AS A SIGNIFICANT UPPER LOW EMERGES INTO THE FRONT RANGE
FROM THE ROCKIES WITH STRONG SOUTHWEST FLOW ALOFT INTO THE DAKOTAS.
AT THE SAME TIME...THE AFOREMENTIONED SURFACE LOW OVER THE FRONT
RANGE WILL HAVE MOVED/DEVELOPED EASTWARD INTO THE WESTERN DAKOTAS.
THESE INGREDIENTS WILL BE FAVORABLE FOR PLENTY OF SHEAR...CAPE
(ESPECIALLY WITH SURFACE DEWPOINTS IN THE 65 TO 70 DEGREE
RANGE)...AND UPPER LEVEL IMPULSES. GOOD CHANCE OF THUNDERSTORMS
THURSDAY AFTERNOON OVER THE WESTERN THIRD OF THE STATE. THIS WILL
CONTINUE INTO THE EVENING HOURS AS WELL...WITH SEVERE WEATHER
POSSIBLE OVER MUCH OF THE FORECAST AREA THURSDAY AFTERNOON/NIGHT.
.LONG TERM...(THURSDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 320 PM CDT WED JUL 23 2014
THE MAIN FEATURES IN THE LONG TERM PERIOD CONTINUE TO BE AN UPPER
LOW OFF THE WA/OR COAST AND ITS INTERACTION WITH THE DOWNSTREAM
H500 RIDGE OVER THE NORTHERN PLAINS. AS THE UPPER LOW MOVES EAST
AND FLATTENS THE RIDGE...A COLD FRONT AT THE SURFACE WILL
POSITION ITSELF ACROSS EASTERN MONTANA BY THURSDAY AFTERNOON. THE
FRONT WILL THEN PUSH EAST ACROSS NORTH DAKOTA THURSDAY
EVENING AND OVERNIGHT INTO FRIDAY MORNING. THUNDERSTORMS...A FEW
POSSIBLY SEVERE WITH STRONG WINDS AND HAIL THE MAIN THREATS WILL
ACCOMPANY THE FRONT AS IT PROGRESSES EAST THROUGH THE STATE
THURSDAY AFTERNOON AND EVENING. ON FRIDAY COOLER BUT STILL
REASONABLY MILD TEMPERATURES IN THE UPPER 70S TO LOWER 80S SHOULD
BE THE RULE. ANY SHOWERS AND ISOLATED THUNDERSTORMS SHOULD BE
LIMITED TO THE EAST. ONE MORE DAY OF SHOWERS/SCATTERED
THUNDERSTORMS ON SATURDAY AS THE SLOW MOVING UPPER LOW TRACKS
SOUTH ACROSS MINNESOTA. WHILE THE STATE WILL GENERALLY BE ON THE
DRY SIDE OF THE UPPER LOW CANT RULE OUT SHOWERS AS COOL AIR ALOFT
SHOULD SUPPORT SOME INSTABILITY...ESPECIALLY NORTH. AS THE UPPER
LOW DRIFTS EAST AND A RIDGE POPS UP IN MONTANA SUNDAY THROUGH
TUESDAY...SHOULD BE DRY WITH GENERALLY PLEASANT TEMPERATURES AND
HUMIDITY FOR THIS TIME OF YEAR.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z THURSDAY EVENING)
ISSUED AT 539 PM CDT WED JUL 23 2014
VFR CONDITIONS OUTSIDE OF THUNDERSTORMS ARE FORECAST FOR THE 00
UTC TAF CYCLE ACROSS WESTERN AND CENTRAL NORTH DAKOTA.
THUNDERSTORMS ARE FORECAST TO ENTER WESTERN NORTH DAKOTA AROUND
03-04 UTC...AND MOVE INTO CENTRAL NORTH DAKOTA BY 08-09 UTC. SEE
TAFS FOR TIMING AND THREAT DETAILS. ANOTHER ROUND OF THUNDERSTORMS
IS EXPECTED LATE THURSDAY AFTERNOON AND INTO THE EVENING.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...AYD
SHORT TERM...JV
LONG TERM...NH
AVIATION...AYD
AREA FORECAST DISCUSSION
NWS GREENVILLE-SPARTANBURG SC
508 PM EDT WED JUL 23 2014
.SYNOPSIS...
WEAK HIGH PRESSURE ATOP THE REGION WILL GIVE WAY TO A SURFACE FRONT
APPROACHING FROM THE NORTHWEST TONIGHT. THE FRONT IS EXPECTED TO
MOVE ACROSS THE CAROLINAS AND NORTH GEORGIA THURSDAY AFTERNOON AND
EVENING. HIGH PRESSURE WILL BUILD IN BEHIND THE FRONT FOR FRIDAY AND
THE WEEKEND. ANOTHER FRONT IS EXPECTED TO PASS ON MONDAY.
&&
.NEAR TERM /THROUGH THURSDAY/...
AT 450 PM EDT...COVERAGE HAS EXPANDED EAST OF THE BLUE RIDGE TO
WARRANT BRIEF CATEGORICAL POP VALUES ACROSS THE NC FOOTHILLS BACK TO
THE IMMEDIATE ESCARPMENT AREAS. OUTFLOWS MAY DRIVE ADDITIONAL
CONVECTION FARTHER S INTO THE SRN FOOTHILLS AND PIEDMONT...SO CHC
POPS HAVE BEEN RAMPED UP THERE AS WELL THROUGH 7 PM. STILL
ANTICIPATE THAT THE STRONGEST STORMS WILL BE MAINLY MARGINAL FOR
SEVERE WIND AND HAIL AS DCAPE VALUES ARE NOT VERY HIGH IN THE BEST
COVERAGE AREAS AND THE PROFILES ARE QUITE WARM WITH FREEZING LEVELS
ABOVE 15 KFT. THE CONVECTION SHOULD WANE QUICKLY WITH THE LOSS OF
HEATING THIS EVENING...SO WILL LOWER POPS QUICKLY IN THE 23Z TO 02Z
TIMEFRAME.
AN UPPER TROUGH IS STILL FORECAST TO BECOME ESTABLISHED ACROSS THE
EASTERN U.S. ON THU AS A STRONG SHORT MOVES THROUGH THE GREAT LAKES.
THE ASSOCIATED SURFACE COLD FRONT CURRENTLY OVER OHIO VALLEY WILL
PUSH SOUTHEAST TO JUST NW OF THE NC MOUNTAINS BY 12Z THU....AND THEN
MOVE ACROSS THE REGION ON THU. WILL CONTINUE WITH THE IDEA THAT SOME
SHOWERS/THUNDERSTORMS COULD REACH THE MOUNTAINS BY SUNRISE.
GUIDANCE IS IN AGREEMENT THAT THE FRONT SHOULD BE ACCOMPANIED BY
NUMEROUS SHOWERS AND THUNDERSTORMS...EVEN OUTSIDE THE MOUNTAINS
WHERE WINDS THROUGH THE VERTICAL PROFILE ARE WESTERLY/DOWNSLOPE IN
NATURE. WILL BUY INTO THE HIGH POPS BEING ADVERTISED AS THE
SURFACE CONVERGENCE ALONG THE FRONT COMBINED WITH THE DIGGING UPPER
TROUGH/FALLING HEIGHTS WILL TAP INTO CAPES POOLING TO BETWEEN 1000-2000J
DURING THE AFTERNOON. SPC IS STILL JUST HIGHLIGHTING THE I-77
CORRIDOR EASTWARD WITH A 5% SEVERE THREAT ON THURSDAY. WITH
IMPROVING SHEAR...WOULD NOT BE SURPRISED TO SEE A FEW SEVERE STORMS
THURSDAY AFTERNOON. MAX TEMPS ON THU WILL BE TEMPERED BY CLOUDS AND
CONVECTION SO THEY SHOULD BE A COUPLE DEGREES LOWER THAN TODAY.
&&
.SHORT TERM /THURSDAY NIGHT THROUGH SATURDAY/...
AS OF 200 PM WED...COLD FRONT WILL CONTINUE TO PUSH THRU THE PIEDMONT
THURSDAY EVENING...WITH AXIS OF DEEP UPPER TROUGH MOVING THRU EARLY
FRI. POPS WILL DECLINE EAST OF THE MTNS FOLLOWING THE END OF
HEATING...WITH LLVL CONVERGENCE UNLIKELY TO OVERCOME THE INHIBITION
RESULTING FROM POOR LAPSE RATES ABOVE THE PBL. PROFILES FROM THE
HIGHER TERRAIN HOWEVER DO SHOW THE EFFECTS OF MIDLEVEL CAA FOLLOWING
THE FRONT...THUS A SCHC POP IS KEPT INTO EARLY FRI MRNG. GOING
FORWARD HOWEVER...HIGH PRESSURE EXPANDS OUT OF THE MIDWEST WHICH
SHOULD PROVIDE AT LEAST A WEAK SUBSIDENCE INVERSION TO CAP OFF MOST
DEEP CONVECTION FRI AND SAT. THE NAM AND A PORTION OF THE SREF
MEMBERS DO NOT SHOW THE INVERSION BEING STRONG ENOUGH TO KEEP THE
ENTIRE CWFA DRY DURING THIS TIME. WILL ADVERTISE SCHC POPS OVER THE
BLUE RIDGE FRI AS WELL AS IN THE LOWER PIEDMONT...WELL SE OF
I-85...WHERE THE HIGH WILL HAVE THE LEAST INFLUENCE. THERE IS BETTER
CONSENSUS FOR A DRY FCST SATURDAY...THOUGH BY THAT TIME THE HIGH HAS
BECOME INDISTINCT DUE TO THE UPPER FLOW BECOMING NEARLY ZONAL. POPS
THUS COULD BE EASILY REINTRODUCED FOR SAT IN SUBSEQUENT FCST
PACKAGES. TEMPS DURING THE SHORT RANGE WILL RETURN TO NEAR NORMAL AS
THICKNESS VALUES INCREASE.
&&
.LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/...
AS OF 1215 PM WEDNESDAY...DURING THE LATTER HALF OF THE UPCOMING
WEEKEND...DIURNALLY ENHANCED TSTM ACTIVITY HAS THE OPPORTUNITY TO
BECOME CONSIDERABLE ON SUNDAY WITHIN DEVELOPING LLVL RETURN FLOW
REGIME UNDERNEATH PROGRESSIVELY LOWERING UPPER HEIGHTS. L/WV TROUGH
AXIS IS PROGGED TO CONTINUE TO DIG INTO THE SE CONUS THROUGH
MONDAY...EVENTUALLY FORCING A COLD FRONT ACRS THE REGION BY MONDAY
NIGHT. WITH PRONOUNCED UPPER LEVEL TROUGH ACRS THE ERN CONUS AND
A CONTINENTAL AIRMASS OVERSPREADING THE REGION...A NOTABLY DRY AND
COOLER FCST IS ON TAP FOR TUESDAY AND WEDNESDAY.
&&
.AVIATION /21Z WEDNESDAY THROUGH MONDAY/...
AT KCLT...ALL CONVECTION THIS AFTN HAS THUS FAR REMAINED WELL NW OR
S OF THE AIRFIELD...AND THE LATEST HRRR RUN STILL DOES NOT SHOW MUCH
CONVECTIVE DEVELOPMENT IN IMMEDIATE AREA LATE THIS AFTERNOON. ..SO
WILL CONTINUE THE VCSH MENTION FOR NOW UNLESS ANY TS GETS CLOSER
THROUGH 00Z. OTHERWISE...THE NIGHT AND EARLY MORNING SHOULD BE QUIET
AND VFR. THE APPROACH OF A COLD FRONT ON THU WARRANTS A PROB30 FOR
TSRA AT THE END OF THE TAF PERIOD.
ELSEWHERE...FAIRLY SOLID COVERAGE HAS DEVELOPED FROM KAVL TO
KHKY...AND ALSO NEARING KGMU TO KGSP ON A SWD MOVING OUTFLOW. THESE
SITES WILL GET TEMPO TSRA THROUGH LATE AFTN...WITH JUST VCTS
MENTIONED AT KAND. OTHERWISE...THE NIGHT SHOULD BE QUIET AND VFR.
THE EXCEPTION IS AT KAVL WHERE LIFR FOG WILL BE IN THE FORECAST
AGAIN FOR EARLY THU. AN APPROACH OF A COLD FRONT ON THU WARRANTS
PROB30 TSRA FOR THE END OF THE TAF PERIOD AT ALL SITES.
OUTLOOK... SHOWERS AND THUNDERSTORMS WILL END THURSDAY EVENING AS A
COLD FRONT MOVES SOUTHEAST OF THE AREA. FRIDAY AND SAT SHOULD BE
QUIET AND VFR...THE EXCEPTION WILL BE THE MOUNTAIN VALLEYS WHERE
EARLY MORNING FOG MAY OCCUR. THUNDERSTORMS WILL RETURN TO THE
FORECAST FOR SUNDAY AFTERNOON THROUGH MONDAY AS ANOTHER COLD FRONT
APPROACHES AND THEN MOVES THROUGH THE AREA ON MONDAY.
CONFIDENCE TABLE...
21-03Z 03-09Z 09-15Z 15-21Z
KCLT HIGH 100% HIGH 100% HIGH 100% HIGH 100%
KGSP HIGH 100% HIGH 100% HIGH 100% HIGH 93%
KAVL HIGH 98% HIGH 94% MED 75% HIGH 85%
KHKY HIGH 100% HIGH 100% HIGH 100% HIGH 93%
KGMU HIGH 100% HIGH 100% HIGH 100% HIGH 93%
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
&&
.GSP WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
NC...NONE.
SC...NONE.
&&
$$
SYNOPSIS...CSH
NEAR TERM...HG/LG
SHORT TERM...WIMBERLEY
LONG TERM...CSH
AVIATION...HG/LG
AREA FORECAST DISCUSSION
NWS GREENVILLE-SPARTANBURG SC
235 PM EDT WED JUL 23 2014
.SYNOPSIS...
WEAK HIGH PRESSURE ATOP THE REGION WILL GIVE WAY TO A SURFACE FRONT
APPROACHING FROM THE NORTHWEST TONIGHT. THE FRONT IS EXPECTED TO
MOVE ACROSS THE CAROLINAS AND NORTH GEORGIA THURSDAY AFTERNOON AND
EVENING. HIGH PRESSURE WILL BUILD IN BEHIND THE FRONT FOR FRIDAY AND
THE WEEKEND. ANOTHER FRONT IS EXPECTED TO PASS ON MONDAY.
&&
.NEAR TERM /THROUGH THURSDAY/...
AT 215 PM...CURRENT RADAR SHOWS THAT THE BEST COVERAGE OF SHOWERS
AND THUNDERSTORMS WAS ALONG THE BLUE RIDGE WITH ONLY ISOLATED
SHOWERS OUTSIDE THE MOUNTAINS. HOWEVER...THE SPC MESO-ANAL SHOWS
SBCAPES ANYWHERE FROM 1500-2000J WITH NO CIN INDICATED.
THEREFORE...SOME SCT TSRA SHOULD DEVELOP IN THE VICINITY OF THE WEAK
LEE TROUGH IN THE MID TO LATE AFTERNOON HOURS...SO WILL CONTINUE THE
FORECAST OF SCATTERED SHOWERS/THUNDERSTORMS. CONVECTION SHOULD WANE
QUICKLY WITH THE LOSS OF HEATING THIS EVENING...SO WILL LOWER POPS
QUICKLY IN THE 23Z-02Z TIMEFRAME.
AN UPPER TROUGH IS STILL FORECAST TO BECOME ESTABLISHED ACROSS THE
EASTERN U.S. ON THU AS A STRONG SHORT MOVES THROUGH THE GREAT LAKES.
THE ASSOCIATED SURFACE COLD FRONT CURRENTLY OVER OHIO VALLEY WILL
PUSH SOUTHEAST TO JUST NW OF THE NC MOUNTAINS BY 12Z THU....AND THEN
MOVE ACROSS THE REGION ON THU. WILL CONTINUE WITH THE IDEA THAT SOME
SHOWERS/THUNDERSTORMS COULD REACH THE MOUNTAINS BY SUNRISE.
GUIDANCE IS IN AGREEMENT THAT THE FRONT SHOULD BE ACCOMPANIED BY
NUMEROUS SHOWERS AND THUNDERSTORMS...EVEN OUTSIDE THE MOUNTAINS
WHERE WINDS THROUGH THE VERTICAL PROFILE ARE WESTERLY/DOWNSLOPE IN
NATURE. WILL BUY INTO THE HIGH POPS BEING ADVERTISED AS THE
SURFACE CONVERGENCE ALONG THE FRONT COMBINED WITH THE DIGGING
UPPER TROUGH/FALLING HEIGHTS WILL TAP INTO CAPES POOLING TO
BETWEEN 1000-2000J DURING THE AFTERNOON. SPC IS STILL JUST
HIGHLIGHTING THE I-77 CORRIDOR EASTWARD WITH A 5% SEVERE THREAT ON
THURSDAY. WITH IMPROVING SHEAR...WOULD NOT BE SURPRISED TO SEE A
FEW SEVERE STORMS THURSDAY AFTERNOON. MAX TEMPS ON THU WILL BE
TEMPERED BY CLOUDS AND CONVECTION SO THEY SHOULD BE A COUPLE
DEGREES LOWER THAN TODAY.
&&
.SHORT TERM /THURSDAY NIGHT THROUGH SATURDAY/...
AS OF 200 PM WED...COLD FRONT WILL CONTINUE TO PUSH THRU THE PIEDMONT
THURSDAY EVENING...WITH AXIS OF DEEP UPPER TROUGH MOVING THRU EARLY
FRI. POPS WILL DECLINE EAST OF THE MTNS FOLLOWING THE END OF
HEATING...WITH LLVL CONVERGENCE UNLIKELY TO OVERCOME THE INHIBITION
RESULTING FROM POOR LAPSE RATES ABOVE THE PBL. PROFILES FROM THE
HIGHER TERRAIN HOWEVER DO SHOW THE EFFECTS OF MIDLEVEL CAA FOLLOWING
THE FRONT...THUS A SCHC POP IS KEPT INTO EARLY FRI MRNG. GOING
FORWARD HOWEVER...HIGH PRESSURE EXPANDS OUT OF THE MIDWEST WHICH
SHOULD PROVIDE AT LEAST A WEAK SUBSIDENCE INVERSION TO CAP OFF MOST
DEEP CONVECTION FRI AND SAT. THE NAM AND A PORTION OF THE SREF
MEMBERS DO NOT SHOW THE INVERSION BEING STRONG ENOUGH TO KEEP THE
ENTIRE CWFA DRY DURING THIS TIME. WILL ADVERTISE SCHC POPS OVER THE
BLUE RIDGE FRI AS WELL AS IN THE LOWER PIEDMONT...WELL SE OF
I-85...WHERE THE HIGH WILL HAVE THE LEAST INFLUENCE. THERE IS BETTER
CONSENSUS FOR A DRY FCST SATURDAY...THOUGH BY THAT TIME THE HIGH HAS
BECOME INDISTINCT DUE TO THE UPPER FLOW BECOMING NEARLY ZONAL. POPS
THUS COULD BE EASILY REINTRODUCED FOR SAT IN SUBSEQUENT FCST
PACKAGES. TEMPS DURING THE SHORT RANGE WILL RETURN TO NEAR NORMAL AS
THICKNESS VALUES INCREASE.
&&
.LONG TERM /SATURDAY NIGHT THROUGH TUESDAY/...
AS OF 1215 PM WEDNESDAY...DURING THE LATTER HALF OF THE UPCOMING
WEEKEND...DIURNALLY ENHANCED TSTM ACTIVITY HAS THE OPPORTUNITY TO
BECOME CONSIDERABLE ON SUNDAY WITHIN DEVELOPING LLVL RETURN FLOW
REGIME UNDERNEATH PROGRESSIVELY LOWERING UPPER HEIGHTS. L/WV TROUGH
AXIS IS PROGGED TO CONTINUE TO DIG INTO THE SE CONUS THROUGH
MONDAY...EVENTUALLY FORCING A COLD FRONT ACRS THE REGION BY MONDAY
NIGHT. WITH PRONOUNCED UPPER LEVEL TROUGH ACRS THE ERN CONUS AND
A CONTINENTAL AIRMASS OVERSPREADING THE REGION...A NOTABLY DRY AND
COOLER FCST IS ON TAP FOR TUESDAY AND WEDNESDAY.
&&
.AVIATION /19Z WEDNESDAY THROUGH MONDAY/...
AT KCLT...MAIN CONCERN IN THE FORECAST IS WHETHER A THUNDERSTORM
WILL AFFECT THE AIRFIELD THIS AFTERNOON. LATEST HRRR RUN DOES NOT
SHOW MUCH CONVECTIVE DEVELOPMENT IN TEH CLT AREA THIS AFTERNOON.
HENCE...WILL STAY THE COURSE WITH JUST A VCSH 20-23Z WHICH SHOULD BE
THE WINDOW FOR THE BEST COVERAGE AROUND THE AIRPORT. OTHERWISE THE
NIGHT AND EARLY MORNIGN SHOULD BE QUIET AND VFR. THE APPROACH OF A
COLD FRONT ON THU WARRANTS A PROB30 FOR TSRA AT THE END OF THE TAF
PERIOD.
ELSEWHERE...THE ONLY TAF SITE IN WHICH CONFIDENCE IS HIGH ENOUGH TO
CARRY TEMPO TSRA IS AT KAVL THIS AFTERNOON. WILL JUST MENTION A VCTS
AT OTHER AIR FIELDS. OTHERWISE...THE NIGHT SHOULD BE QUIET AND VFR.
THE EXCEPTION IS AT KAVL WHERE LIFR FOG WILL BE IN THE FORECAST
AGAIN FOR EARLY THU. AN APPROACH OF A COLD FRONT ON THU WARRANTS
PROB30 TSRA FOR THE END OF THE TAF PERIOD AT ALL SITES.
OUTLOOK... SHOWERS AND THUNDERSTORMS WILL END THURSDAY EVENING AS A
COLD FRONT MOVES SOUTHEAST OF THE AREA. FRIDAY AND SAT SHOULD BE
QUIET AND VFR...THE EXCEPTION WILL BE THE MOUNTAIN VALLEYS WHERE
EARLY MORNING FOG MAY OCCUR. THUNDERSTORMS WILL RETURN TO THE
FORECAST FOR SUNDAY AFTERNOON THROUGH MONDAY AS ANOTHER COLD FRONT
APPROACHES AND THEN MOVES THROUGH THE AREA ON MONDAY.
CONFIDENCE TABLE...
18-24Z 00-06Z 06-12Z 12-18Z
KCLT HIGH 98% HIGH 100% HIGH 100% HIGH 100%
KGSP HIGH 100% HIGH 100% HIGH 100% HIGH 100%
KAVL HIGH 92% HIGH 100% MED 76% HIGH 84%
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
&&
.GSP WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
NC...NONE.
SC...NONE.
&&
$$
SYNOPSIS...CSH
NEAR TERM...LG
SHORT TERM...WIMBERLEY
LONG TERM...CSH
AVIATION...LG
AREA FORECAST DISCUSSION
NWS GREENVILLE-SPARTANBURG SC
148 PM EDT WED JUL 23 2014
.SYNOPSIS...
WEAK HIGH PRESSURE ATOP THE REGION WILL GIVE WAY TO A SURFACE FRONT
APPROACHING FROM THE NORTHWEST TONIGHT. THE FRONT IS EXPECTED TO
MOVE ACROSS THE CAROLINAS AND NORTH GEORGIA THURSDAY AFTERNOON AND
EVENING. HIGH PRESSURE WILL BUILD IN BEHIND THE FRONT FOR FRIDAY AND
THE WEEKEND. ANOTHER FRONT IS EXPECTED TO PASS ON MONDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
AT NOON EDT...RADAR SHOWS NUMEROUS SHOWERS DEVELOPING OVER THE
MOUNTAINS...SO THE IDEA OF HIGHER POPS OVER THE TERRAIN IS WORKING
OUT. THE LATEST HRRR IS SHOWING A BIT MORE CONVECTIVE COVERAGE OVER
THE FOOTHILLS AND PIEDMONT THIS AFTERNOON WHICH ISN`T SURPRISING
SINCE CAPES HAVE INCREASED TO 1500-2000J. HOWEVER...COVERAGE SHOULD
STILL BE SCATTERED IN NATURE. THEREFORE...ADJUSTED POPS PER CURRENT
TRENDS FOR THE AFTERNOON. ALSO MADE SOME MINOR ADJUSTMENTS TO OTHER
GRID FIELDS BASED ON CURRENT OBS AND LATEST CONSHORT RUN.
AS OF 1015 AM...SEE NO REASON BASED ON CURRENT TRENDS AND CAMS TO
DEVIATE MUCH FROM THE OFFICIAL GRIDS. BASED ON OUR CAMPOP AND TCU
DEVLOPING PER SAT PICS...I DID BUMP UP THE POPS IN THE NC CENTRAL
AND SW MOUNTAINS TO SOLID LIKELY THIS AFTERNOON. OTHERWISE...
CONVECTIVE DEVELOPMENT SHOULD BE SCATTERED. TEMPS ARE CURRENTLY
RISING RAPIDLY SO UPPER 80S STILL LOOKS GOOD FOR MAX TEMPS.
AS OF 6 AM...LATEST 11U-3.9U SATELLITE IMAGES INDICATED AN EXPANDING
AREA OF LOW CLOUDS ACROSS THE PIEDMONT AND WEST TO THE SOUTHERN NC
FOOTHILLS. SFC OBSERVATIONS SHOW A WIDE RANGE OF
VISIBILITIES...RANGING FROM M1/4SM AT KMRN TO 10SM ACROSS THE
GREENVILLE/SPARTANBURG/ANDERSON AREAS. THE LOWEST VISIBILITIES ARE
GENERALLY ACROSS THE I-77 CORRIDOR AND WITHIN THE MTN VALLEYS. ALL
PREFERRED GUIDANCE INDICATES THAT THE FOG WILL DISSIPATE DURING THE
TWO HOURS FOLLOWING SUNRISE. I WILL UPDATE THE FORECAST TO ADJUST
FOG AND VISIBILITIES TO THE LATEST OBSERVATIONS AND THINKING. IN
ADDITION...LATEST MOS HAS TRENDED WARMER FOR THIS AFTERNOON...I WILL
WARM FORECAST HIGHS A CLICK. OTHERWISE...THE CURRENT FORECAST IS IN
GOOD SHAPE.
AS OF 320 AM...EARLY MORNING FOG IS EXPECTED TO DEVELOP AND EXPAND
ACROSS THE I-77 CORRDIOR AND WITHIN THE MTN VALLEYS. THE HRRR
CONDENSATION PRESSURE DEFICITS INDICATES THAT THE LOWEST VALUES
WILL EXIST ACROSS THE SOUTHEASTERN HALF OF THE CHARLOTTE METRO AREAS
AND WITHIN THE MTN VALLEYS. FOG SHOULD DISSIPATE DURING THE FIRST
TWO HOURS OF SUNLIGHT. IN ADDITION...EARLY MIXING SHOULD YIELD A
LIGHT SOUTHWEST WIND. GREATER INSOLATION AND SOUTHWEST WINDS SHOULD
RESULT IN STEADILY WARMING TEMPERATURES FROM SUNRISE TO MID
AFTERNOON. I WILL FORECAST HIGHS TO RANGE FROM THE L80S WITHIN THE
MTNS VALLEYS TO U80S TO NEAR 90 EAST OF I-85.
RECENT W/V LOOP INDICATED THAT THE MID LEVEL LOW WAS DRIFTING WEST
ACROSS THE MISSISSIPPI RIVER DELTA...AS ANOTHER TROUGH WILL DIGGING
OVER THE OHIO RIVER VALLEY. AT THE SFC...A WEAK LEE TROUGH MAY
DEVELOP ACROSS THE PIEDMONT DURING THE AFTERNOON. A COLD FRONT WILL
APPROACH FROM THE NW TODAY...REACHING THE SOUTHERN APPALACHIANS LATE
TONIGHT. CAMS INDICATE THAT SHRA AND TSRA WILL FAVOR THE MTNS AND
ADJACENT FOOTHILLS AS EARLY AS MID MORNING TODAY. COVERAGE WILL
INCREASE THROUGH THE HEAT OF THE AFTERNOON...BECOMING SCT ACROSS THE
PIEDMONT. CONVECTION SHOULD GENERALLY DISSIPATE EAST OF THE MTNS ONE
TO TWO HOURS AFTER SUNSET. HOWEVER...I WILL MAINTAIN CHC TO LIKELY
POPS ACROSS THE TN BORDER COUNTIES TO COVER THE ARRIVAL OF PRE
FRONTAL CONVECTION. LOW TEMPERATURES TONIGHT ARE FORECAST TO RANGE
FROM THE MID 60S ACROSS THE MTNS TO LOW 70S EAST.
&&
.SHORT TERM /THURSDAY THROUGH FRIDAY NIGHT/...
AS OF 230 AM EDT WEDNESDAY...THE MODEL GUIDANCE HAS COME INTO BETTER
AGREEMENT WITH THE PASSAGE OF A SURFACE FRONT MORE OR LESS DURING
PEAK HEATING ON THURSDAY. THE FRONT WILL BE DRIVEN ACROSS THE FCST
AREA BY A FAIRLY STRONG SHORT WAVE IN THE PRESENCE OF SOME UPPER
DIVERGENCE IN THE ENTRANCE REGION OF THE JET OVER THE NORTHEAST.
PLENTY OF LOW LEVEL MOISTURE WILL REMAIN AHEAD OF THE FRONT AS WELL.
THUS...WITH THE TIMING A BIT MORE IN FOCUS...FEEL IT APPROPRIATE TO
BUMP THE PRECIP PROBABILITY UP INTO THE LIKELY RANGE ACROSS THE
ENTIRE FCST AREA IN THE AFTERNOON. MIGHT BE A BIT TOO EARLY TO TALK
TOO MUCH ABOUT SEVERE WEATHER POTENTIAL...BUT THE FRONT SHOULD FOCUS
STORMS IN AN AIR MASS WITH 1500-2500 J/KG OF CAPE...SO THE DAY2
OUTLOOK SEEMS APPROPRIATE. SUSPECT WE WILL HAVE TO CONTEND WITH
SEVERAL SEVERE THUNDERSTORMS. THE FRONT WILL DROP SE DURING THE
EVENING HOURS ENDING THE PRECIP CHANCE BY THE EARLY MORNING HOURS ON
FRIDAY.
BEHIND THE FRONT...THE AIR MASS WILL NOT REALLY BE MUCH COOLER...BUT
IT SHOULD BE A BIT DRIER ON FRIDAY. HIGH PRESSURE SHOULD MOVE IN
DURING THE DAY. NOT REALLY SEEING MUCH TO SUPPORT ANY SHOWERS IN THE
AFTERNOON SO THE PRECIP CHANCES WERE LOWERED. FRIDAY NIGHT SHOULD BE
DRY AS WELL WITH SEASONAL TEMPS.
&&
.LONG TERM /SATURDAY THROUGH WEDNESDAY/...
AS OF 1215 PM WEDNESDAY...DURING THE LATTER HALF OF THE UPCOMING
WEEKEND...DIURNALLY ENHANCED TSTM ACTIVITY HAS THE OPPORTUNITY TO
BECOME CONSIDERABLE ON SUNDAY WITHIN DEVELOPING LLVL RETURN FLOW
REGIME UNDERNEATH PROGRESSIVELY LOWERING UPPER HEIGHTS. L/WV TROUGH
AXIS IS PROGGED TO CONTINUE TO DIG INTO THE SE CONUS THROUGH
MONDAY...EVENTUALLY FORCING A COLD FRONT ACRS THE REGION BY MONDAY
NIGHT. WITH PRONOUNCED UPPER LEVEL TROUGH ACRS THE ERN CONUS AND
A CONTINENTAL AIRMASS OVERSPREADING THE REGION...A NOTABLY DRY AND
COOLER FCST IS ON TAP FOR TUESDAY AND WEDNESDAY.
&&
.AVIATION /18Z WEDNESDAY THROUGH MONDAY/...
AT KCLT...MAIN CONCERN IN THE FORECAST IS WHETHER A THUNDERSTORM
WILL AFFECT THE AIRFIELD THIS AFTERNOON. LATEST HRRR RUN DOES NOT
SHOW MUCH CONVECTIVE DEVELOPMENT IN TEH CLT AREA THIS AFTERNOON.
HENCE...WILL STAY THE COURSE WITH JUST A VCSH 20-23Z WHICH SHOULD BE
THE WINDOW FOR THE BEST COVERAGE AROUND THE AIRPORT. OTHERWISE THE
NIGHT AND EARLY MORNIGN SHOULD BE QUIET AND VFR. THE APPROACH OF A
COLD FRONT ON THU WARRANTS A PROB30 FOR TSRA AT THE END OF THE TAF
PERIOD.
ELSEWHERE...THE ONLY TAF SITE IN WHICH CONFIDENCE IS HIGH ENOUGH
TO CARRY TEMPO TSRA IS AT KAVL THIS AFTERNOON. WILL JUST MENTION A
VCTS AT OTHER AIR FIELDS. OTHERWISE...THE NIGHT SHOULD BE QUIET
AND VFR. THE EXCEPTION IS AT KAVL WHERE LIFR FOG WILL BE IN THE
FORECAST AGAIN FOR EARLY THU. AN APPROACH OF A COLD FRONT ON THU
WARRANTS PROB30 TSRA FOR THE END OF THE TAF PERIOD AT ALL SITES.
OUTLOOK... SHOWERS AND THUNDERSTORMS WILL END THURSDAY EVENING AS A
COLD FRONT MOVES SOUTHEAST OF THE AREA. FRIDAY AND SAT SHOULD BE
QUIET AND VFR...THE EXCEPTION WILL BE THE MOUNTAIN VALLEYS WHERE
EARLY MORNING FOG MAY OCCUR. THUNDERSTORMS WILL RETURN TO THE
FORECAST FOR SUNDAY AFTERNOON THROUGH MONDAY AS ANOTHER COLD FRONT
APPROACHES AND THEN MOVES THROUGH THE AREA ON MONDAY.
CONFIDENCE TABLE...
17-23Z 23-05Z 05-11Z 11-17Z
KCLT HIGH 100% HIGH 100% HIGH 100% HIGH 100%
KGSP HIGH 100% HIGH 100% HIGH 100% HIGH 100%
KAVL HIGH 92% HIGH 100% MED 76% MED 77%
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
&&
.GSP WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
NC...NONE.
SC...NONE.
&&
$$
SYNOPSIS...PM
NEAR TERM...LG
SHORT TERM...PM
LONG TERM...PM
AVIATION...LG
AREA FORECAST DISCUSSION
NWS GREENVILLE-SPARTANBURG SC
1202 PM EDT WED JUL 23 2014
.SYNOPSIS...
WEAK HIGH PRESSURE ACROSS THE AREA TODAY WILL MOVE AWAY TONIGHT. A
SURFACE FRONT WILL APPROACH FROM THE NORTHWEST TONIGHT AND IS
EXPECTED TO MOVE ACROSS THE CAROLINAS AND NORTH GEORGIA THURSDAY
AFTERNOON AND EVENING. HIGH PRESSURE WILL BUILD IN BEHIND THE FRONT
FOR FRIDAY AND THE WEEKEND. ANOTHER FRONT IS EXPECTED TO PASS ON
MONDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
AT NOON EDT...RADAR SHOWS NUMEROUS SHOWERS DEVELOPING OVER THE
MOUNTAINS...SO THE IDEA OF HIGHER POPS OVER THE TERRAIN IS WORKING
OUT. THE LATEST HRRR IS SHOWING A BIT MORE CONVECTIVE COVERAGE OVER
THE FOOTHILLS AND PIEDMONT THIS AFTERNOON WHICH ISN`T SURPRISING
SINCE CAPES HAVE INCREASED TO 1500-2000J. HOWEVER...COVERAGE SHOULD
STILL BE SCATTERED IN NATURE. THEREFORE...ADJUSTED POPS PER CURRENT
TRENDS FOR THE AFTERNOON. ALSO MADE SOME MINOR ADJUSTMENTS TO OTHER
GRID FIELDS BASED ON CURRENT OBS AND LATEST CONSHORT RUN.
AS OF 1015 AM...SEE NO REASON BASED ON CURRENT TRENDS AND CAMS TO
DEVIATE MUCH FROM THE OFFICIAL GRIDS. BASED ON OUR CAMPOP AND TCU
DEVLOPING PER SAT PICS...I DID BUMP UP THE POPS IN THE NC CENTRAL
AND SW MOUNTAINS TO SOLID LIKELY THIS AFTERNOON. OTHERWISE...
CONVECTIVE DEVELOPMENT SHOULD BE SCATTERED. TEMPS ARE CURRENTLY
RISING RAPIDLY SO UPPER 80S STILL LOOKS GOOD FOR MAX TEMPS.
AS OF 6 AM...LATEST 11U-3.9U SATELLITE IMAGES INDICATED AN EXPANDING
AREA OF LOW CLOUDS ACROSS THE PIEDMONT AND WEST TO THE SOUTHERN NC
FOOTHILLS. SFC OBSERVATIONS SHOW A WIDE RANGE OF
VISIBILITIES...RANGING FROM M1/4SM AT KMRN TO 10SM ACROSS THE
GREENVILLE/SPARTANBURG/ANDERSON AREAS. THE LOWEST VISIBILITIES ARE
GENERALLY ACROSS THE I-77 CORRIDOR AND WITHIN THE MTN VALLEYS. ALL
PREFERRED GUIDANCE INDICATES THAT THE FOG WILL DISSIPATE DURING THE
TWO HOURS FOLLOWING SUNRISE. I WILL UPDATE THE FORECAST TO ADJUST
FOG AND VISIBILITIES TO THE LATEST OBSERVATIONS AND THINKING. IN
ADDITION...LATEST MOS HAS TRENDED WARMER FOR THIS AFTERNOON...I WILL
WARM FORECAST HIGHS A CLICK. OTHERWISE...THE CURRENT FORECAST IS IN
GOOD SHAPE.
AS OF 320 AM...EARLY MORNING FOG IS EXPECTED TO DEVELOP AND EXPAND
ACROSS THE I-77 CORRDIOR AND WITHIN THE MTN VALLEYS. THE HRRR
CONDENSATION PRESSURE DEFICITS INDICATES THAT THE LOWEST VALUES
WILL EXIST ACROSS THE SOUTHEASTERN HALF OF THE CHARLOTTE METRO AREAS
AND WITHIN THE MTN VALLEYS. FOG SHOULD DISSIPATE DURING THE FIRST
TWO HOURS OF SUNLIGHT. IN ADDITION...EARLY MIXING SHOULD YIELD A
LIGHT SOUTHWEST WIND. GREATER INSOLATION AND SOUTHWEST WINDS SHOULD
RESULT IN STEADILY WARMING TEMPERATURES FROM SUNRISE TO MID
AFTERNOON. I WILL FORECAST HIGHS TO RANGE FROM THE L80S WITHIN THE
MTNS VALLEYS TO U80S TO NEAR 90 EAST OF I-85.
RECENT W/V LOOP INDICATED THAT THE MID LEVEL LOW WAS DRIFTING WEST
ACROSS THE MISSISSIPPI RIVER DELTA...AS ANOTHER TROUGH WILL DIGGING
OVER THE OHIO RIVER VALLEY. AT THE SFC...A WEAK LEE TROUGH MAY
DEVELOP ACROSS THE PIEDMONT DURING THE AFTERNOON. A COLD FRONT WILL
APPROACH FROM THE NW TODAY...REACHING THE SOUTHERN APPALACHIANS LATE
TONIGHT. CAMS INDICATE THAT SHRA AND TSRA WILL FAVOR THE MTNS AND
ADJACENT FOOTHILLS AS EARLY AS MID MORNING TODAY. COVERAGE WILL
INCREASE THROUGH THE HEAT OF THE AFTERNOON...BECOMING SCT ACROSS THE
PIEDMONT. CONVECTION SHOULD GENERALLY DISSIPATE EAST OF THE MTNS ONE
TO TWO HOURS AFTER SUNSET. HOWEVER...I WILL MAINTAIN CHC TO LIKELY
POPS ACROSS THE TN BORDER COUNTIES TO COVER THE ARRIVAL OF PRE
FRONTAL CONVECTION. LOW TEMPERATURES TONIGHT ARE FORECAST TO RANGE
FROM THE MID 60S ACROSS THE MTNS TO LOW 70S EAST.
&&
.SHORT TERM /THURSDAY THROUGH FRIDAY NIGHT/...
AS OF 230 AM EDT WEDNESDAY...THE MODEL GUIDANCE HAS COME INTO BETTER
AGREEMENT WITH THE PASSAGE OF A SURFACE FRONT MORE OR LESS DURING
PEAK HEATING ON THURSDAY. THE FRONT WILL BE DRIVEN ACROSS THE FCST
AREA BY A FAIRLY STRONG SHORT WAVE IN THE PRESENCE OF SOME UPPER
DIVERGENCE IN THE ENTRANCE REGION OF THE JET OVER THE NORTHEAST.
PLENTY OF LOW LEVEL MOISTURE WILL REMAIN AHEAD OF THE FRONT AS WELL.
THUS...WITH THE TIMING A BIT MORE IN FOCUS...FEEL IT APPROPRIATE TO
BUMP THE PRECIP PROBABILITY UP INTO THE LIKELY RANGE ACROSS THE
ENTIRE FCST AREA IN THE AFTERNOON. MIGHT BE A BIT TOO EARLY TO TALK
TOO MUCH ABOUT SEVERE WEATHER POTENTIAL...BUT THE FRONT SHOULD FOCUS
STORMS IN AN AIR MASS WITH 1500-2500 J/KG OF CAPE...SO THE DAY2
OUTLOOK SEEMS APPROPRIATE. SUSPECT WE WILL HAVE TO CONTEND WITH
SEVERAL SEVERE THUNDERSTORMS. THE FRONT WILL DROP SE DURING THE
EVENING HOURS ENDING THE PRECIP CHANCE BY THE EARLY MORNING HOURS ON
FRIDAY.
BEHIND THE FRONT...THE AIR MASS WILL NOT REALLY BE MUCH COOLER...BUT
IT SHOULD BE A BIT DRIER ON FRIDAY. HIGH PRESSURE SHOULD MOVE IN
DURING THE DAY. NOT REALLY SEEING MUCH TO SUPPORT ANY SHOWERS IN THE
AFTERNOON SO THE PRECIP CHANCES WERE LOWERED. FRIDAY NIGHT SHOULD BE
DRY AS WELL WITH SEASONAL TEMPS.
&&
.LONG TERM /SATURDAY THROUGH TUESDAY/...
AS OF 315 AM WEDNESDAY...STILL EXPECTING THE MEAN UPPER TROF OVER
THE EAST TO FILL OVER THE WEEKEND AS A SHORT WAVE RIDGE MOVES
THROUGH. THIS WILL SUPPORT WEAK HIGH PRESSURE FOR SATURDAY AND INTO
SUNDAY. THINK CONVECTION WILL BE LIMITED TO THE RIDGETOPS SATURDAY
AFTERNOON AND HAVE CUT BACK THE ALREADY MEAGER POP A BIT MORE.
EARLIER RUNS OF THE MODELS SHOWED THE POTENTIAL FOR UPSTREAM MCS
DEVELOPMENT ON SATURDAY NIGHT...AND THAT COULD STILL HAPPEN...BUT
THE MAIN FOCUS LOOKS LIKE IT WILL BE MORE LIKE THE OH VALLEY AND
CENTRAL APPALACHIANS. SO...SATURDAY NIGHT WAS KEPT DRY ACROSS THE
MOUNTAINS AS WELL. EXPECT MORE OF A RETURN TO DIURNAL THUNDERSTORMS
FOR SUNDAY. ANOTHER IN A SERIES OF FAIRLY STRONG SHORT WAVES WILL
ONCE AGAIN CARVE OUT AN UPPER TROF OVER THE EAST EARLY NEXT WEEK. IT
STILL LOOKS LIKE THIS WAVE WILL DRIVE ANOTHER COLD FRONT OVER THE
REGION ON MONDAY. UNLIKE THE EARLIER FRONT...THIS ONE SHOULD USHER
IN A NOTICEABLY DIFFERENT AIR MASS FOR NEXT TUESDAY AS A COOL
CONTINENTAL HIGH MOVES DOWN OVER THE NRN PLAINS...THEN MODIFIES AND
BUILDS IN FROM THE WEST. THAT SHOULD DROP TEMPS A CATEGORY OR MORE
BELOW NORMAL.
&&
.AVIATION /16Z WEDNESDAY THROUGH SUNDAY/...
AT KCLT AND ELSEWHERE...LATEST 11U-3.9U SATELLITE IMAGES INDICATED AN
EXPANDING AREA OF LOW CLOUDS ACROSS THE PIEDMONT AND WEST TO THE
SOUTHERN NC FOOTHILLS. SFC OBSERVATIONS SHOW A WIDE RANGE OF
VISIBILITIES...RANGING FROM M1/4SM AT KAVL/KMRN TO 10SM ACROSS THE
GREENVILLE/SPARTANBURG/ANDERSON AREAS. THE LOWEST VISIBILITIES ARE
GENERALLY ACROSS THE I-77 CORRIDOR AND WITHIN THE MTN VALLEYS. ALL
PREFERRED GUIDANCE INDICATES THAT THE FOG WILL DISSIPATE DURING THE
TWO HOURS FOLLOWING SUNRISE THIS MORNING. BY 14Z...SW WINDS SHOULD
DEVELOP WITH VFR CLOUD COVER. SCT PIEDMONT COVERAGE OF LATE
AFTERNOON TSRA ARE POSSIBLE 18Z TO 24Z. TSRA COVERAGE WILL BE
SIGNIFICANTLY GREATER ACROSS THE MTNS...HIGHLIGHTED WITH A TEMPO
18Z-21Z. ANOTHER ROUND OF LIFR FOG/CIGS ARE POSSIBLE ACROSS THE MTNS
LATE TONIGHT...PATCHY MVFR OVER WET GROUND EAST.
OUTLOOK... SHOWERS AND THUNDERSTORMS THURSDAY WITH THE PASSAGE OF A
COLD FRONT. SCATTERED SHOWERS AND THUNDERSTORMS MAINLY DURING THE
AFTERNOONS AND EVENINGS THROUGH THE END OF THE WEEK.
CONFIDENCE TABLE...
16-22Z 22-04Z 04-10Z 10-16Z
KCLT HIGH 99% HIGH 100% HIGH 100% HIGH 100%
KGSP HIGH 100% HIGH 100% HIGH 100% HIGH 100%
KAVL HIGH 92% HIGH 97% MED 71% LOW 50%
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 89%
THE PERCENTAGE REFLECTS THE NUMBER OF GUIDANCE MEMBERS AGREEING
WITH THE SCHEDULED TAF ISSUANCE FLIGHT RULE CATEGORY. COMPLETE
HOURLY EXPERIMENTAL AVIATION FORECAST CONSISTENCY TABLES AND ENSEMBLE
FORECASTS ARE AVAILABLE AT THE FOLLOWING LINK: (MUST BE LOWER CASE)
WWW.WEATHER.GOV/GSP/AVIATION_TABLES
&&
.GSP WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
NC...NONE.
SC...NONE.
&&
$$
SYNOPSIS...PM
NEAR TERM...LG
SHORT TERM...PM
LONG TERM...PM
AVIATION...NED
AREA FORECAST DISCUSSION FOR WESTERN SD AND NORTHEASTERN WY
NWS RAPID CITY SD
242 PM MDT WED JUL 23 2014
.SHORT TERM...THIS EVENING THROUGH THURSDAY NIGHT
ISSUED AT 240 PM MDT WED JUL 23 2014
WATER VAPOR IMAGERY SHOWS STRONG UPPER RIDGING ACROSS MUCH OF THE
WRN TO CNTRL CONUS WITH THE MAIN AXIS FROM CO TO MT. AN UPPER LOW IS
SITTING JUST OFFSHORE THE PACIFIC NORTHWEST WITH SW FLOW OVER THE NW
CONUS...THEN TRANSITIONING TO NW FLOW OVER THE CWA. SURFACE ANALYSIS
SHOWS HIGH PRESSURE ACROSS THE UPPER MIDWEST...AND LOW PRESSURE OVER
MONTANA WITH RETURN FLOW OVER THE HIGH PLAINS. TEMPS HAVE STRUGGLED
TO REACH FORECAST HIGHS WITH TEMPS SO FAR IN THE 80S TO LOWER 90S.
STRONG CAP IN PLACE ACROSS MUCH OF THE CWA WILL KEEP DIURNALLY
TRIGGERED CONVECTION FROM DEVELOPING TODAY. THE CAP WAS EXPECTED TO
BE WEAKEST ACROSS NE WY WHERE TEMPS REACHING MID 90S WOULD BE ENOUGH
TO ERODE IT...BUT TEMPS HAVE BEEN SHORT OF THAT SO FAR. CONVECTION
HAS INITIATED OVER LARAMIE RANGE...AND THE LATEST HRRR RUN SHOWS
THIS CONVECTION MOVING N/NE INTO NE WY AND SW SD THIS EVENING. HAVE
PUT IN ISOLATED POPS THIS EVENING TO ACCOUNT FOR THIS...AND POSSIBLE
OTHER CONVECTION THAT MOVES IN FROM THE WEST. BUT OVERALL MOST AREAS
WILL STAY DRY TONIGHT. ANY STORMS THAT MAKE IT INTO THE AREA MAY BE
SEVERE...BUT OVERALL SEVERE THREAT TONIGHT IS VERY LOW.
UPPER RIDGE AXIS SLIDES EASTWARD THURSDAY...CROSSING THE NRN PLAINS.
UPPER LOW WILL CROSS THE NRN ROCKIES WITH THE SURFACE LOW PUSHING
ACROSS THE CWA. TEMPS ARE EXPECTED TO REACH THE 90S TO 100. A COLD
FRONT WILL SLIDE SE...CROSSING THE CWA THU AFTN/NIGHT. A STRONG CAP
IN PLACE AGAIN WILL HELP KEEP CONVECTION FROM DEVELOPING...BUT COULD
SEE ISOLATED STORMS DEVELOP AS THE FRONT PUSHES THROUGH...PERHAPS
ELEVATED STORMS. CANT RULE OUT A COUPLE STORMS BECOMING SEVERE...BUT
OVERALL THREAT LOOKS MINIMAL AGAIN.
&&
.LONG TERM...FRIDAY THROUGH WEDNESDAY
ISSUED AT 240 PM MDT WED JUL 23 2014
UPPER-LEVEL RIDGE OVER THE REGION BREAKS DOWN BY THE END OF THE WEEK
AS AN UPPER LOW SLIDES SOUTHEAST ACROSS SOUTH CENTRAL CANADA. A WEAK
SHORTWAVE IN ZONAL FLOW TO THE SOUTH COULD BRING ANOTHER CHANCE FOR
SHOWERS AND THUNDERSTORMS TO AT LEAST PORTIONS OF THE CWA FRIDAY
AFTERNOON AND NIGHT.
AS THE UPPER LOW SLIDES FURTHER EAST OF THE REGION...THE UPPER RIDGE
WILL REBUILD OVER THE WESTERN CONUS...BRINGING PREDOMINANTLY
NORTHWEST FLOW TO THE NORTHERN PLAINS. THIS WILL RESULT IN COOLER
TEMPERATURES FOR THE REST OF THE EXTENDED PERIOD...ALONG WITH MAINLY
DRY CONDITIONS FROM SATURDAY THROUGH MONDAY. WEAK SHORTWAVE
DISTURBANCES WILL BEGIN TO ROTATE AROUND THE RIDGE AND INTO THE
NORTHERN PLAINS AGAIN BY THE MIDDLE OF NEXT WEEK. WILL KEEP LOW
CHANCE POPS ACROSS PORTIONS OF THE AREA FROM MONDAY NIGHT THROUGH
WEDNESDAY.
&&
.AVIATION...FOR THE 18Z TAFS THROUGH 18Z THURSDAY
ISSUED AT 240 PM MDT WED JUL 23 2014
VFR CONDITIONS ARE GENERALLY EXPECTED THROUGH THE FORECAST PERIOD.
ISOLATED THUNDERSTORMS ARE POSSIBLE LATE TODAY ACROSS NORTHEAST WY
AND TONIGHT ACROSS NORTHEAST WY AND MUCH OF WESTERN SD.
&&
.UNR WATCHES/WARNINGS/ADVISORIES...
SD...NONE.
WY...NONE.
&&
$$
SHORT TERM...13
LONG TERM...26
AVIATION...26
AREA FORECAST DISCUSSION FOR WESTERN SD AND NORTHEASTERN WY
NWS RAPID CITY SD
1142 AM MDT WED JUL 23 2014
.UPDATE...
ISSUED AT 1141 AM MDT WED JUL 23 2014
UPPER RIDGE REMAINS ACROSS THE REGION WITH LOW LEVEL RETURN FLOW
AND THERMAL RIDGE BRINGING WARMER AIR BACK INTO TO THE CWA. 12Z
MODELS ARE TRENDING DRIER FOR THIS AFTN AND EVNG AS MORE
SIGNIFICANT UPPER WAVE ACTIVITY STAYS NORTH OF THE CWA. STRONG CAP
IN PLACE WILL KEEP CONVECTION FROM FORMING ACROSS MOST OF WRN SD.
WILL DROP POPS THIS AFTERNOON NOW...AND THIS EVENING WITH THE
LATER FORECAST ISSUANCE. NAM SHOWS ENOUGH EROSION OF THE CAP
ACROSS THE WARMER NE WY TO WILL LEAVE SL CHC POPS THIS AFTN...AND
OVER THE BLKHLS AREA. HRRR IS SHOWING VERY ISOLATED STORMS
DEVELOPING OVER PORTIONS OF NE WY INTO THE NW SD PLAINS INTO THE
EARLY EVENING.
&&
.SHORT TERM...TODAY THROUGH THURSDAY NIGHT
ISSUED AT 230 AM MDT WED JUL 23 2014
08Z SURFACE ANALYSIS HAD LEE TROUGH FROM CENTRAL MT INTO
SOUTHEAST WY. WEAK OUTFLOW BOUNDARIES NOTED ACROSS SOUTHEAST MT
INTO CENTRAL SD. CLUSTER OF SEVERE CONVECTION HEADING SOUTHEAST
ACROSS SOUTHERN PORTIONS OF THE CWA EARLY THIS MORNING...SPURRED
ON BY WEAK SHORTWAVE OVER NORTHEAST WY PER WATER VAPOUR LOOP AND
30KT LOW LEVEL JET. BEHIND IT...UPPER RIDGE BUILDING OVER MT/WY
WITH UPSTREAM WAVES OVER ID/WESTERN MT. SHORT RANGE GUIDANCE SHOWS
ORGANIZED TSRA EXITING CWA BY 12Z...BUT COULD BE A FEW LINGERING
CELLS EARLY.
TODAY...UPPER RIDGE AMPLIFIES INTO THE NORTHERN PLAINS WITH THERMAL
RIDGE SLOWLY BUILDING. LEE TROUGH SHIFTS EAST A BIT WITH LOW
PRESSURE DEVELOPING OVER CENTRAL WY IN RESPONSE TO SHORTWAVE
ROTATING AROUND RIDGE INTO MT. SURFACE HIGH OVER THE MIDWEST
COMBINED WITH WY LOW RESULTS IN SOMEWHAT TIGHT PRESSURE GRADIENT AND
STRENGTHENING SOUTH/SOUTHEAST FLOW UP TO 25KTS. AHEAD OF LEE
TROUGH...2-4KJ/KG MLCAPE DEVELOPS BY AFTERNOON WITH MLCIN
WEAKENING...ESPECIALLY AFTER 21Z. DIRECT UPSTREAM MID-LEVEL
SHORTWAVES HARD TO DEPICT IN GUIDANCE OR TO SEE UPSTREAM ON WATER
VAPOUR...BUT A COUPLE OF WEAK 700MB SHORTWAVES FORECAST BY MODELS
TO SHIFT INTO EASTERN WY LATE IN THE DAY. THIS SHOULD PROVIDE THE
LAST NUDGE TO ALLOW TSRA TO ERUPT. 0-6KM BULK SHEAR 15-20M/S WITH
RATHER SLOW RIGHT-MOVING SUPERCELL MOVEMENT...IN THE 5-10KT RANGE.
0-6KM MEAN WIND 15-20KTS. WITH SLIGHTLY FASTER MOVEMENT THAN
GUIDANCE SHOWED YESTERDAY...IT APPEARS FLASH FLOOD POTENTIAL NOT
AS CLEARLY DEFINED...ALTHOUGH PRECIPITABLE WATERS DO REACH 150
PERCENT OF NORMAL. LOCAL FLASH FLOOD COMPOSITE PARAMETER HAS
BACKED OFF NOTICEABLY. THUS WILL HOLD OFF ON ANY WATER HEADLINES
AT THIS POINT AND PASS ON CONCERN TO DAY SHIFT. TEMPERATURES WILL
BE NEAR GUIDANCE IN THE WEST AND NEAR BIAS CORRECTED VALUES IN THE
EAST.
TONIGHT...LOW PRESSURE CONSOLIDATES OVER EASTERN MT WITH WARM FRONT
ACROSS NORTHERN SD. ACTIVITY WILL SLOWLY SHIFT EAST AS 30-40KT LOW
LEVEL JET DEVELOPS/INTERSECTS WARM FRONT...TRANSLATING BEST
850-700MB THETA-E ADVECTION EAST OF AREA AFTER MIDNIGHT.
TEMPERATURES WILL STAY UP GIVEN PERSISTENT SOUTHERLY FLOW.
THURSDAY...UPPER RIDGE FLOPS OVER IN RESPONSE TO SHORTWAVE/UPPER LOW
MOVING ACROSS SOUTHERN BC/AB. LOW PRESSURE OVER EASTERN MT WILL MOVE
INTO CENTRAL SD. AHEAD OF IT...STRONG THERMAL RIDGE PEAKS OVER CWA
WITH DRY LINE SURGING INTO SOUTHWEST SD FROM WY. TRAILING COOL FRONT
BEHIND LOW WILL DROP INTO CWA IN THE AFTERNOON. 1-2KJ/KG POST
FRONTAL MLCAPE DEVELOPS OVER THE NORTHERN HALF OF CWA. 2-3KJ/KG
MLCAPE IN WARM SECTOR LIKELY...BUT MLCIN WILL BE MUCH STRONGER
THERE. 0-6KM SHEAR SUFFICIENT FOR SUPERCELLS POST FRONTAL IN THE
NORTH...WITH MARGINAL VALUES IN THE SOUTH...BUT DEEP MIXING MAY
PROMOTE SEVERE WIND GUSTS WITH ANY CONVECTION THAT DEVELOPS OVER
SOUTHWEST SD. EXPECT SEVERE STORMS LATER THURSDAY AFTERNOON IN THE
FAR NORTH. TEMPERATURES WILL BE SLIGHTLY BELOW GUIDANCE POST FRONTAL
AND HAVE ADJUSTED NEAR/ABOVE GUIDANCE SOUTH OF DRY LINE.
THURSDAY NIGHT...COOL FRONT SURGES THROUGH CWA WITH BREEZY SPOTS
BEHIND IT AND CONVECTION MOVING EAST OF THE CWA OVERNIGHT.
TEMPERATURES NEAR GUIDANCE.
&&
.LONG TERM...FRIDAY THROUGH TUESDAY
ISSUED AT 230 AM MDT WED JUL 23 2014
UPPER-LEVEL RIDGE BREAKS DOWN BY THE END OF THE WEEK AS A STRONG
SHORTWAVE TROF SLIDES SOUTHEAST ACROSS SOUTH CENTRAL CANADA. THIS
WILL BRING ANOTHER CHANCE OF SHOWERS AND STORMS TO THE AREA ON
FRIDAY INTO SATURDAY.
AS THE SHORTWAVE TROF SLIDES EAST...THE UPPER RIDGE WILL RETROGRADE
WEST...BRINGING PREDOMINANTLY NORTHWEST UPPER FLOW TO THE NORTHERN
PLAINS. THIS WILL RESULT IN COOLER TEMPERATURES FOR THE REST OF THE
EXTENDED PERIOD...ALONG WITH MAINLY DRY CONDITIONS.
&&
.AVIATION...FOR THE 18Z TAFS THROUGH 18Z THURSDAY
ISSUED AT 1115 AM MDT WED JUL 23 2014
VFR CONDITIONS ARE GENERALLY EXPECTED THROUGH THE FORECAST PERIOD.
ISOLATED THUNDERSTORMS ARE POSSIBLE LATE TODAY ACROSS NORTHEAST WY
AND TONIGHT ACROSS NORTHEAST WY AND MUCH OF WESTERN SD.
&&
.UNR WATCHES/WARNINGS/ADVISORIES...
SD...NONE.
WY...NONE.
&&
$$
UPDATE...13
SHORT TERM...HELGESON
LONG TERM...15
AVIATION...26
AREA FORECAST DISCUSSION
NWS MEMPHIS TN
315 PM CDT WED JUL 23 2014
.DISCUSSION...
CURRENTLY...A COLD FRONT IS PUSHING SOUTH TOWARD THE REGION THIS
AFTERNOON TRIGGERING SHOWERS AND THUNDERSTORMS ACROSS PARTS OF THE
MIDSOUTH. ONE MCS HAS MOVED ACROSS WRN KY/SE MO INTO THE MO
BOOTHEEL AND NE AR THIS AFTERNOON WITH SOME REPORTS OF WIND
DAMAGE. ANOTHER CLUSTER OF STRONG STORMS AND HEAVY RAIN EXTENDS
JUST SOUTH OF I-40 FROM SELMER NORTHEAST TOWARD LEXINGTON
INCLUDING JACKSON.
STORMS ARE FEEDING ON A VERY UNSTABLE AIRMASS WITH DEWPOINTS IN
THE LOWER 70S...CAPES GREATER THAN 3000 J/KG AND LIFTED INDEX
VALUES OF -7C TO -8C. WIND FIELDS ALOFT ARE NOT THAT STRONG WITH
MID LEVEL AT ABOUT 30 KTS...BUT ENOUGH TO SUSTAIN ORGANIZATION.
A SEVERE THUNDERSTORM WATCH CONTINUES UNTIL 7 PM ACROSS MO
BOOTHEEL AND MUCH OF EAST ARKANSAS. THE MCS OVER NE AR WILL
CONTINUE TO PROPAGATE SSW OVER THE NEXT COUPLE OF HOURS WITH
MAINLY A WIND THREAT. ELSEWHERE EXPECT ISOLD-SCT STORMS TO DEVELOP
SOME OF WHICH MAY BE STRONG TO SEVERE WITH MAINLY A WIND THREAT AS
WELL. LOCALIZED FLASH FLOODING IS ALSO POSSIBLE WITH HEAVIER SLOW
MOVING STORMS.
TONIGHT...MCS WILL DEPART INTO CENTRAL ARKANSAS BY EARLY THIS
EVENING AND A COLD FRONT WILL SWEEP SOUTH. MODELS ARE INDICATING
SOME ADDITIONAL DEVELOPMENT ALONG THE FRONT AS IT PASSES THROUGH.
AT THAT POINT INSTABILITY SHOULD BE ON THE WANE WITH A DIMINISHING
SEVERE THREAT. BY MIDNIGHT MOST OF THE ACTIVITY WILL BE SOUTH OF
I-40 WITH A DRIER...COOLER AIRMASS BEGINNING TO MOVE INTO NORTHERN
AREAS.
THURSDAY AND FRIDAY...THE FRONT WILL PUSH SOUTH OF THE AREA
THURSDAY MORNING WITH CLEARING SKIES AND DIMINISHING RAIN CHANCES.
AN UNSEASONABLY COOL AND DRY AIRMASS WILL PUSH IN FOR THURSDAY AND
THURSDAY NIGHT. HIGHS WILL BE IN THE LOWER TO MID 80S WITH LOWS IN
THE UPPER 50S TO MID 60S. FRIDAY WILL BE A LITTLE WARMER...THOUGH
HUMIDITY LEVELS WILL STILL BE LOW...AS UPPER LEVEL HIGH PRESSURE
STARTS TO BUILD BACK IN.
SATURDAY AND SUNDAY...SUMMER HEAT TRIES TO BUILD OVER THE AREA
THANKS TO A STRENGTHENING 594 DM UPPER RIDGE OVER THE SOUTHERN
PLAINS. LOOKS LIKE HIGHS WILL REBOUND INTO THE LOWER AND MID 90S
WITH INCREASING HUMIDITY LEVELS. STILL THINK THE MEX IS TOO HOT
WITH ITS UPPER 90S. HEAT INDEX VALUES MAY CLIMB ABOVE 100 DEGREES
OVER THE WEEKEND. BY SATURDAY NIGHT AN APPROACHING COLD FRONT MAY
LAUNCH AN MCS ACROSS THE NORTHERN TIER OF THE MIDSOUTH SO KEPT
SLIGHT CHANCE POPS ACROSS THE NORTHERN TIER. THUNDERSTORMS CHANCES
WILL INCREASE ACROSS THE AREA SUNDAY INTO SUNDAY NIGHT AS ANOTHER
COLD FRONT IS DRIVEN THROUGH THE AREA BY ANOTHER UNSEASONABLY
STRONG UPPER TROF ACROSS THE GREAT LAKES.
MONDAY INTO WEDNESDAY...DRY AND COOL WEATHER FILTERS IN BEHIND THE
FRONT. WELL BELOW NORMAL TEMPERATURES AND DRY WEATHER EXPECTED.
SJM
&&
.AVIATION...
18Z TAF CYCLE
VFR AND POSSIBLY MVFR CONDITIONS ARE EXPECTED THROUGHOUT
THE FORECAST PERIOD. THUNDERSTORMS HAVE BEGUN TO MOVE INTO THE
AREA AHEAD OF A COLD FRONT EXTENDING FROM QUEBEC INTO THE
SOUTHERN PLAINS. THE HRRR MODEL HAS COVERAGE OF THESE STORMS
DECREASING AS THEY ENTER INTO THE REGION. ADDED VCTS FOR KJBR AND
KMKL THROUGH THIS EVENING. A LOW PRESSURE SYSTEM OVER THE NORTHERN
GULF HAS CAUSED THUNDERSTORM ACTIVITY OVER NORTH MISSISSIPPI SO I
ADDED VCTS AT KTUP. FOG IS POSSIBLE TONIGHT AT KTUP AND KMKL DUE
TO LIGHT WINDS AND LOWER LEVEL MOISTURE. WINDS WILL BE SOUTH AHEAD
OF THE FRONT AND WILL TURN TO THE NORTH AFTER THE FRONT PASSES
EACH TAF SITE BEGINNING WITH KJBR AROUND 00Z.
JPM3
&&
.MEG WATCHES/WARNINGS/ADVISORIES...
AR...NONE.
MO...NONE.
MS...NONE.
TN...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS NASHVILLE TN
305 PM CDT WED JUL 23 2014
.DISCUSSION...A FRONT ALONG THE OHIO RIVER THIS AFTERNOON WILL
PUSH INTO MID TN WITH AT LEAST SCATTERED THUNDERSTORMS CONTINUING
INTO TONIGHT. THE DYNAMICS AND WIND WITH THIS FRONT ARE FAIRLY
WEAK...AND SHORT RANGE MODELS ARE DEPICTING RATHER SPARSE THUNDERSTORM
COVERAGE THIS EVENING. STILL...WE WILL STICK WITH LIKELY POPS FOR
AREAS AROUND BNA AND EASTWARD SINCE THE FRONT WILL BE ENCOUNTERING
A MODERATELY UNSTABLE ATMOSPHERE WITH PW VALUES NEAR 2 INCHES.
THIS WILL NOT BE A WIDESPREAD BIG RAINFALL PRODUCER...BUT A FEW
SPOTS WILL PICK UP SOME HEAVY DOWNPOURS. POPS WILL TREND DOWNWARD
AFTER DARK...SINCE MUCH OF THE CONVECTION WILL BE HEAT DRIVEN.
ON THURSDAY...WE WILL KEEP SMALL POPS IN THE FORECAST DUE TO THE
SLUGGISH FRONT MOVEMENT AND A SECONDARY MID LEVEL TROUGH PASSAGE.
COOLER AND DRIER AIR WILL BE MOVING IN WITH NORTH WINDS AND HIGHS
MAINLY IN THE LOW TO MID 80S.
THURSDAY NIGHT THROUGH SATURDAY...MID TN WILL BE UNDER THE
INFLUENCE OF HIGH PRESSURE. UPPER HEIGHTS WILL BE ELEVATED ...SO
TEMPERATURES WILL REBOUND QUICKLY. HIGHS WILL BE WELL INTO THE 80S
FRIDAY...AND LOWER 90S SATURDAY. HUMIDITY LEVELS WILL BE PLEASANT
ENOUGH THURSDAY NIGHT...BUT BECOMING STICKY BY LATE SATURDAY.
THE NEXT SYSTEM WILL BRING A CHANCE FOR THUNDERSTORMS BY SUNDAY
WITH A FRONTAL PASSAGE EXPECTED SUNDAY NIGHT. INSTABILITY
PARAMETERS ON SUNDAY AFTERNOON ARE RATHER IMPRESSIVE SO STRONG
STORMS WITH SOME HEAVY DOWNPOURS LOOKS POSSIBLE.
A FAIRLY POTENT SURFACE HIGH FOR LATE JULY WILL THEN BUILD IN
FROM THE NORTH. THERMAL TROUGHING LOOKS IMPRESSIVE WITH 850 MB
TEMPS DOWN TO 10 DEG C. HIGHS IN THE LOWER TO MID 80S WITH LOW
RELATIVE HUMIDITY ARE EXPECTED MONDAY THROUGH WEDNESDAY.
13
&&
.PREV DISCUSSION... /ISSUED 1210 PM CDT WED JUL 23 2014/
AVIATION...
RADAR SHOWS SHRA/TSRA NOW SCATTERED AROUND THE ENTIRE MID STATE
AND NEAR ALL 3 TAF SITES. LEANED HEAVILY ON LATEST HRRR MODEL
RUNS...AND WILL MENTION VCTS AT ALL AIRPORTS THROUGH THE AFTERNOON
WITH A BRIEF FEW HOURS BREAK IN ACTIVITY BEFORE MORE CONVECTION IN
THE EVENING. VFR CONDITIONS GENERALLY EXPECTED OVERALL BUT MVFR
CIGS/VIS POSSIBLE IN HEAVIER SHOWERS/STORMS. LIGHT WEST TO
SOUTHWEST WINDS THIS AFTERNOON WILL BECOME NORTHWEST BY EVENING AS
WEAK FRONTAL BOUNDARY SHIFTS SOUTHWARD.
SHAMBURGER
&&
.PRELIMINARY POINT TEMPS/POPS...
NASHVILLE 70 83 63 89 / 60 20 0 0
CLARKSVILLE 65 81 58 88 / 40 10 0 0
CROSSVILLE 66 79 58 84 / 70 30 10 0
COLUMBIA 68 83 62 90 / 60 20 05 0
LAWRENCEBURG 69 83 63 89 / 50 30 10 0
WAVERLY 65 81 59 89 / 40 10 0 0
&&
.OHX WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS MEMPHIS TN
110 PM CDT WED JUL 23 2014
.UPDATE...
UPDATED FOR 18Z AVIATION DISCUSSION.
&&
.PREV DISCUSSION... /ISSUED 1110 AM CDT WED JUL 23 2014/
DISCUSSION...
THE MIDSOUTH IS BETWEEN TWO SYSTEMS TODAY. THERE IS THE WEAK UPPER
LOW SITTING TO THE SOUTH NEAR NEW ORLEANS AND A COLD FRONT
APPROACHING FROM THE NORTH. THE WEAK UPPER LOW IS THROWING SOME
MOISTURE UP OVER NORTH MISSISSIPPI AND THIS SHOULD RESULT IN ISOLD-
SCT SHOWERS AND THUNDERSTORMS THIS AFTERNOON AS THE AIRMASS
CONTINUES TO DESTABILIZE. MEANWHILE TO THE NORTH...A COLD FRONT IS
PRESSING SOUTH. THIS FEATURE HAS KICKED OF AN AREA OF
THUNDERSTORMS NEAR THE CONFLUENCE OF THE OH/MS RIVERS. THESE
STORMS HAVE BEEN PROPAGATING SWWD THANKS TO THE DEEP NORTHEAST FLOW
ALOFT. THIS TREND WILL PROBABLY CONTINUE AND ADDITIONAL ACTIVITY
SHOULD DEVELOP ACROSS NORTHEAST ARKANSAS AND THE MO BOOTHEEL THIS
AFTERNOON...PER 13Z HRRR. UPPED POPS SLIGHTLY...TO 50 PERCENT
ACROSS MUCH OF THE NORTH WHILE DROPPING POPS BACK TO 20 PERCENT IN
THE MEMPHIS METRO AREA. A FEW STRONG TO SEVERE STORMS ARE POSSIBLE
LATER THIS AFTERNOON...ESPECIALLY ACROSS NORTHEAST ARKANSAS AND
THE MO BOOTHEEL. DAMAGING WINDS WILL BE THE MAIN THREAT. UPDATE
ALREADY OUT.
SJM
PREV DISCUSSION... /ISSUED 221 AM CDT WED JUL 23 2014/
AN UPPER LEVEL LOW LOCATED NEAR NEW ORLEANS WILL CONTINUE TO BRING
CHANCES FOR SHOWERS AND THUNDERSTORMS TO NORTHEAST MISSISSIPPI
TODAY. ALTHOUGH...THE SHOWERS AND THUNDERSTORMS HAVE DISSIPATED
OVER THE LAST COUPLE OF HOURS. EXPECT REDEVELOPMENT TO OCCUR BY
MID-MORNING WITH CHANCES INCREASING BY THE AFTERNOON HOURS. THE
SHOWERS AND THUNDERSTORMS MAY ALSO AFFECT PORTIONS OF WEST
TENNESSEE NEAR THE TENNESSEE RIVER.
MEANWHILE...A COLD FRONT WILL APPROACH THE MIDSOUTH TODAY. EXPECT
SOME SHOWERS AND POSSIBLY A FEW THUNDERSTORMS AHEAD OF THE FRONT
TO AFFECT NORTHEAST ARKANSAS AND THE MISSOURI BOOTHEEL THIS
MORNING. CHANCES WILL INCREASE BY THIS AFTERNOON ACROSS THIS AREA
AND INTO NORTHWEST TENNESSEE AS THE FRONT PUSHES INTO THE AREA.
CAN/T RULE OUT A FEW STORMS BECOMING STRONG TO SEVERE THIS
AFTERNOON INTO THIS EVENING. DAMAGING WINDS AND/OR LARGE HAIL
WOULD BE THE MAIN THREATS FROM THESE STORMS. HIGHS WILL BE IN THE
UPPER 80S TO LOWER 90S.
THE COLD FRONT WILL CONTINUE TO PUSH THROUGH THE REST OF THE
MIDSOUTH TONIGHT. CHANCES FOR SHOWERS AND THUNDERSTORMS WILL SHIFT
SOUTH TO SOUTHWEST TENNESSEE AND NORTH MISSISSIPPI BY THE LATE
EVENING AND OVERNIGHT HOURS.
THURSDAY INTO FRIDAY...PLEASANT WEATHER WILL OCCUR BEHIND THE
FRONT AS SFC HIGH PRESSURE BUILDS INTO THE AREA FROM THE OHIO
VALLEY BRINGING COOLER AND DRIER AIR INTO THE MIDSOUTH. HIGHS ON
THURSDAY WILL BE IN THE LOWER TO MID 80S. LOWS THURSDAY NIGHT WILL
BE IN THE UPPER 50S TO MID 60S. THE HIGH WILL QUICKLY SHIFT EAST
BY FRIDAY BUT EVEN THOUGH WARMER TEMPERATURES ARE EXPECTED ON
FRIDAY THE DRY AIR WILL REMAIN IN PLACE THUS NOT FEELING AS WARM.
HOT AND HUMID CONDITIONS WILL RETURN ON SATURDAY AND WILL CONTINUE
UNTIL ANOTHER COLD FRONT PUSHES THROUGH THE AREA SUNDAY INTO
SUNDAY NIGHT. CHANCES FOR SHOWERS AND THUNDERSTORMS WILL OCCUR
AHEAD OF THE FRONT.
BEAUTIFUL WEATHER WILL RETURN FOR THE BEGINNING AND MIDDLE PART OF
NEXT WEEK AS SFC HIGH PRESSURE SETTLES OVER THE REGION BEHIND THE
FRONT. HIGHS WILL BE IN THE LOWER TO MIDDLE 80S WITH LOWS LIKELY
IN THE UPPER 50S TO MID 60S.
&&
.AVIATION...
18Z TAF CYCLE
VFR AND POSSIBLY MVFR CONDITIONS ARE EXPECTED THROUGHOUT
THE FORECAST PERIOD. THUNDERSTORMS HAVE BEGUN TO MOVE INTO THE
AREA AHEAD OF A COLD FRONT EXTENDING FROME QUEBEC INTO THE
SOUTHERN PLAINS. THE HRRR MODEL HAS COVERAGE OF THESE STORMS
DECREASING AS THEY ENTER INTO THE REGION. ADDED VCTS FOR KJBR AND
KMKL THROUGH THIS EVENING. A LOW PRESSURE SYSTEM OVER THE NORTHERN
GULF HAS CAUSED THUNDERSTORM ACTIVITY OVER NORTH MISSISSIPPI SO I
ADDED VCTS AT KTUP. FOG IS POSSIBLE TONIGHT AT KTUP AND KMKL DUE
TO LIGHT WINDS AND LOWER LEVEL MOISTURE. WINDS WILL BE SOUTH AHEAD
OF THE FRONT AND WILL TURN TO THE NORTH AFTER THE FRONT PASSES
EACH TAF SITE BEGINNING WITH KJBR AROUND 00Z.
JPM3
&&
.MEG WATCHES/WARNINGS/ADVISORIES...
AR...NONE.
MO...NONE.
MS...NONE.
TN...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS NASHVILLE TN
1210 PM CDT WED JUL 23 2014
.UPDATE...
18Z TAF DISCUSSION.
&&
.AVIATION...
RADAR SHOWS SHRA/TSRA NOW SCATTERED AROUND THE ENTIRE MID STATE
AND NEAR ALL 3 TAF SITES. LEANED HEAVILY ON LATEST HRRR MODEL
RUNS...AND WILL MENTION VCTS AT ALL AIRPORTS THROUGH THE
AFTERNOON WITH A BRIEF FEW HOURS BREAK IN ACTIVITY BEFORE MORE
CONVECTION IN THE EVENING. VFR CONDITIONS GENERALLY EXPECTED
OVERALL BUT MVFR CIGS/VIS POSSIBLE IN HEAVIER SHOWERS/STORMS.
LIGHT WEST TO SOUTHWEST WINDS THIS AFTERNOON WILL BECOME NORTHWEST
BY EVENING AS WEAK FRONTAL BOUNDARY SHIFTS SOUTHWARD.
SHAMBURGER
&&
.PREV DISCUSSION... /ISSUED 1036 AM CDT WED JUL 23 2014/
UPDATE...
RADAR IMAGERY THIS MORNING SHOWS MCS MOVING SOUTHWARD ACROSS
WESTERN KY CONTINUES TO WEAKEN...BUT ADDITIONAL CONVECTION IS
FORMING ON OUTFLOW AHEAD OF THE COMPLEX. OTHER SHOWERS AND STORMS
ARE NOW DEVELOPING ACROSS THE MID STATE. LATEST HRRR RUNS SUGGEST
SCATTERED SHOWERS AND STORMS WILL BLOSSOM THROUGH NOON THEN
CONTINUE INTO THE AFTERNOON BEFORE DIMINISHING...WITH ADDITIONAL
ACTIVITY DEVELOPING THIS EVENING. HOWEVER...EARLIER RUNS HAD
DIFFERENT SOLUTIONS...LEADING TO LOW CONFIDENCE IN EVENTUAL
COVERAGE AND PLACEMENT OF STORMS. NEVERTHELESS...WILL BEGIN HIGH
CHANCE POPS NOW AND CONTINUE THROUGH THE AFTERNOON. CANNOT RULE
OUT SOME STRONGER STORMS MAINLY THIS AFTERNOON WITH LI VALUES NEAR
-6 AND CONSIDERABLE DRY AIR NOTED ALOFT ON 12Z OHX SOUNDING...BUT
NOT ANTICIPATING ANY WIDESPREAD STRONG OR SEVERE ACTIVITY. OTHER
ADJUSTMENTS WERE MADE TO GRIDS BASED ON LATEST OBS...BUT REST OF
FORECAST IS ESSENTIALLY UNCHANGED.
SHAMBURGER
PREV DISCUSSION... /ISSUED 738 AM CDT WED JUL 23 2014/
UPDATE...FOR 12Z TAFS
AVIATION...
A FRONTAL BOUNDARY WILL MOVE INTO MIDDLE TN FROM THE NW LATER TODAY
BRINGING THUNDERSTORMS AND SHOWERS. SOME STRONG STORMS WILL BE
POSSIBLE. INTRODUCED VICINITY STORMS AT CKV AROUND 18Z. WILL HAVE
TO SEE HOW CONVECTION MOVING INTO WESTERN KENTUCKY TRACKS THIS
MORNING TO INCLUDE SOMETHING MORE THAN VICINITY. LATEST HRRR IS
FORECASTING REDEVELOPMENT OF A LINE OF STORMS LATER THIS MORNING
THAT FALLS APART BEFORE IMPACTING NW MIDDLE TN. REGARDLESS IF THAT
LINE DOES FALL APART CONDITIONS WILL BE FAVORABLE FOR SCATTERED
THUNDERSTORMS BY 22Z FOR BNA AND CSV. WINDS WILL SHIFT TO BE OUT
OF THE NW AROUND 00Z TODAY FOR CKV AND BNA...AROUND 02Z FOR CSV.
SOME LIGHT SHOWERS MAY LINGER OVERNIGHT TONIGHT WITH CIGS FALLING
TO 3KFT OR LESS BY MIDNIGHT AND DECREASING VIS FOR CKV AND BNA.
PREV DISCUSSION... /ISSUED 344 AM CDT WED JUL 23 2014/
DISCUSSION...
UPPER LOW IS LOCATED NEAR NEW ORLEANS THIS MORNING WITH AN
INVERTED TROUGH AXIS EXTENDING NORTHEASTWARD ACROSS EASTERN TN.
MEANWHILE...SFC BOUNDARY EXTENDS FROM LAKE ERIE SW THROUGH MO.
NORTHWESTERLY FLOW ALOFT TO BECOME MORE ENHANCED AS WE MOVE
THROUGH TODAY. THIS WILL ALLOW THIS FRONTAL BOUNDARY TO MOVE OUR
WAY AND MOVE ACROSS THE AREA TONIGHT. 18Z AND 00Z DEPICTIONS OF
THE UPPER LEVEL FLOW REVEAL A DIVERGING FLOW ALOFT AND THIS WILL
COUPLE WITH ELEVATED LEVELS OF CURVATURE AND SHEAR JUST TO THE
NORTHWEST OF THE DIVERGING FLOW. LATEST HRRR IN SUPPORT OF LATE
MORNING TO EARLY AFTERNOON CONVECTIVE DEVELOPMENT ACROSS OUR
SOUTHEAST WHICH IS IN CLOSER PROXIMITY TO THE INVERTED TROUGH.
THEN...BY MID AND LATE AFTERNOON...THE APPROACHING FRONTAL
BOUNDARY WILL KICK OFF SOME CONVECTION ACROSS THE NORTHWEST HALF
OF MIDDLE TN. ALL IN ALL...POPS OF 30-50 PERCENT LOOKS REASONABLE
FOR TODAY. CAPES WILL REACH 2000 J/KG BY LATE AFTERNOON SO CANNOT
RULE OUT SOME STRONG STORMS THIS AFTERNOON AND EVENING AS WELL.
SO...AGAIN TONIGHT...A GOOD CHANCE OF SHOWERS AND TSTMS WILL BE IN
THE FORECAST AS THE FROPA OCCURS AND PVA WORKS ACROSS OUR AREA.
THE FRONTAL BOUNDARY WILL BE A SLOW MOVER. THUS...LOW POPS WILL BE
INCLUDED FOR THURSDAY AS WELL.
FOR THE NEAR TERM TEMPS...ANOTHER WARM TO HOT DAY TODAY AS THE FRONT
PRESSES DOWN SLOWLY FROM THE NORTH. NOT NEARLY AS HOT ON THURSDAY AS
THE REPLACING AIRMASS FEATURES A REASONABLY IMPRESSIVE THERMAL
TROUGH FOR THIS TIME OF YEAR. THURSDAY LOOKS LIKE HIGHS IN THE
LOWER TO MID 80S WITH DEWPOINTS IN THE LOWER 60S. LOWER 60S FOR
LOWS ARE EXPECTED THU NT.
IN THE EXT FCST...UPPER TROUGHING WILL PULL EAST AS RIDGING ATTEMPTS
TO EXPAND EASTWARD FROM THE SOUTHWESTERN U.S.. NORTHWEST FLOW WILL
BE WEAKER BUT JUST STRONG ENOUGH TO ALLOW ANOTHER COLD FRONT TO MOVE
OUR WAY THIS WEEKEND. AS THE FRONT REACHES THE MID STATE ON SUNDAY
NIGHT...UPPER TROUGHING OVER THE EASTERN U.S. IS EXPECTED TO
AMPLIFY. LOOKS LIKE WE COULD SEE SOME APPRECIABLE RAINFALL FOR
SUNDAY AND SUNDAY NIGHT. INSTABILITY PARAMETERS ON SUNDAY AFTERNOON
ARE RATHER IMPRESSIVE SO ANOTHER ROUND OF STRONG STORMS LOOKS
POSSIBLE.
A FAIRLY POTENT SFC HIGH FOR LATE JULY WILL THEN BUILD IN FROM THE
NORTH. THERMAL TROUGHING LOOKS IMPRESSIVE WITH 850 MB TEMPS OF
AROUND 12C. HIGH TEMPS IN THE LOWER TO MID 80S WITH LOW RELATIVE
HUMIDITY IS EXPECTED MON THROUGH WED OF NEXT WEEK. WILL BE
UNDERCUTTING THE MEX NUMBERS AS THE EURO SOLUTION IS EVEN STRONGER
WITH THE THERMAL TROUGHING.
&&
.OHX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
55
AREA FORECAST DISCUSSION
NWS CHEYENNE WY
1118 AM MDT WED JUL 23 2014
.UPDATE...
ISSUED AT 850 AM MDT WED JUL 23 2014
EAST UPSLOPE FLOW IS CURRENTLY HOLDING THE LOW CLOUDS IN PLACE
ACROSS MUCH OF SOUTHEAST WYOMING EAST OF THE LARAMIE RANGE AND
INTO PARTS OF THE NEBRASKA PANHANDLE. LOW CLOUDS SHOULD MIX OUT BY
LATE THIS MORNING. NOT EXPECTING A BIG IMPACT ON HIGH TEMPERATURES
OR CHANCES FOR THUNDERSTORMS TODAY. ISOLATED CONVECTION
TO DEVELOP OVER THE MOUNTAINS BY EARLY THIS AFTERNOON. LOW CLOUDS
AND STABLE MID LEVEL AIR LEFT BEHIND FORM LAST NIGHTS
THUNDERSTORMS WILL INITIALLY INHIBIT EASTWARD MOVEMENT OF
THUNDERSTORMS INTO THE PLAINS. ONE THING OF NOTE IS THE STABLE
LAYER THAT IS IN PLACE MAY BE STRONGER THAN MODELS SUGGEST...WHICH
COULD HAVE A BROADER IMPACT ON DECREASING THUNDERSTORM CHANCES.
AT THIS TIME IS APPEARS THE MAIN CHANCES FOR THUNDERSTORMS IN THE
PLAINS WILL BE LATE THIS AFTERNOON AND EVENING WITH THE GREATEST
THREAT INTO EAST CENTRAL WYOMING AND THE NORTHERN NEBRASKA
PANHANDLE. THIS IS ALSO WHERE THE MAIN THREAT FOR SEVERE
THUNDERSTORMS WILL BE GIVEN A STRONGER SHEAR PROFILE AND HIGHER
CAPE VALUES. MAIN THREAT WILL BE THE LARGE HAIL BUT STRONG WINDS
AND AN AN ISOLATED TORNADO POSSIBLE. WITH ANY LUCK MOST
THUNDERSTORM ACTIVITY IN THE PLAINS WILL HOLD OFF UNTIL LATE THIS
EVENING AS THE LOW LEVEL JET RAMPS UP AND STRONGER MID LEVEL
THETAE ADVECTION KICKS IN. THIS WILL MAKE FOR THE MAIN THUNDERSTORM
CHANCES TOWARD CHADRON AND POINTS NORTH AND EAST OF THE FORECAST
AREA.
&&
.SHORT TERM...(TODAY THROUGH FRIDAY)
ISSUED AT 300 AM MDT WED JUL 23 2014
LOTS OF FORECAST CHALLENGES WITH THIS FORECAST PACKAGE...RANGING
FROM SEVERE CONVECTIVE WEATHER TODAY TO FIRE WEATHER CONCERNS
THURSDAY AND FRIDAY.
CURRENTLY...THE MUCH ANTICIPATED COLD FRONT DID MOVE INTO THE AREA
LAST EVENING AND IS CURRENTLY LOCATED GENERALLY ALONG A LINE FROM
CASPER...ALONG THE LARAMIE RANGE DOWN TO LARAMIE AND THEN INTO
NORTHEASTERN COLORADO. THIS FRONT IS SEPARATING VERY MOIST AIR
EAST OF THE FRONT...CHEYENNE HAS A 1AM DEWPOINT OF 57F/LARAMIE
55F...FROM VERY DRY AIR OUT OVER CARBON COUNTY WHERE THE DEWPOINT
AT RAWLINS IS 29F. THIS FEATURE IS GOING TO PLAY A MAJOR ROLE IN
TODAYS FORECAST WEATHER.
FOR TODAY...FRONT IS GOING TO REMAIN AT ITS CURRENT LOCATION
THROUGH THE MORNING HOURS BEFORE IT STARTS TO GET FORCED EAST WITH
INCREASING WESTERLY FLOW. LATEST HRRR FORECAST COMPOSITE
REFLECTIVITY HAS CONVECTION INITIATING ACROSS ALBANY COUNTY AND
THE SOUTH LARAMIE RANGE RIGHT AROUND 20Z TODAY DURING PEAK
HEATING. NAM SOUNDING FOR CHEYENNE HAS CAPE AROUND 1300 J/KG AT
THAT TIME WITH NO CONVECTIVE INHIBITION. PANHANDLE STAYS CAPPED A
LITTLE LONGER...NOT BREAKING THE CAP UNTIL AFTER 00Z. MUCH MORE
UNSTABLE OUT THERE WITH CHADRON NAM SOUNDING SHOWING SBCAPE CLOSE
TO 3500 J/KG. THINK DAY 1 SPC SLIGHT RISK AREA IS PRETTY
GOOD...BUT DO THINK THE LARAMIE COUNTY IS GOING TO SEE SOME SEVERE
THUNDERSTORMS AS WELL AND HAVE TAILORED OUR FORECAST WITH LARAMIE
COUNTY EXPERIENCING SEVERE THUNDERSTORMS THIS AFTERNOON. SEVERE
THUNDERSTORMS INITIALLY OVER THE SOUTHEAST WYOMING PLAINS...THEN
SPREADING EAST INTO THE PANHANDLE AFTER 00Z...AS THE FRONT MOVES
EAST AS A DRY LINE.
FOR THURSDAY...UPPER LOW MOVES INTO MONTANA THURSDAY AFTERNOON
WITH 700MB WINDS INCREASING OVER WYOMING. BY 18Z GFS 700MB WINDS
INCREASE TO 25-30KTS OVER CARBON AND ALBANY COUNTIES. BOTH THE GFS
AND ECMWF SHOW A UPPER LEVEL SHORTWAVE TRACKING THROUGH THE UPPER
RIDGE ALONG THE COLORADO/WYOMING LINE THAT WILL INTERACT WITH SOME
RESIDUAL MONSOONAL MOISTURE TO CREATE AFTERNOON THUNDERSTORMS. GFS
HAS PRECIP MAINLY OVER COLORADO...WHILE ECMWF SPREAD THIS MOISTURE
NORTH INTO WYOMING. DID A BLEND OF THE TWO MODELS WITH CHANCE
SHOWERS AND THUNDERSTORMS OVER SOUTHERN WYOMING NEAR THE COLORADO
BORDER, FORECAST SOUNDING SHOW THE POSSIBILITY OF DRY
THUNDERSTORMS OUT WEST OF THE LARAMIE RANGE THAT HAS ME A LITTLE
WORRIED ABOUT FIRE STARTS AS AFTERNOON MIN HUMIDITIES FALL TO 10
PERCENT ACROSS CARBON...NORTH ALBANY AND WEST CONVERSE COUNTIES.
WENT AHEAD WITH A FIRE WEATHER WATCH FOR THURSDAY FOR CONVERSE
COUNTY AS THIS AREA LOOKS TO BE THE BEST FOR A COMBINATION OF LOW
HUMIDITIES...GUSTY WINDS AND DRY THUNDERSTORMS.
GUSTY WEST WINDS CONTINUE INTO FRIDAY WITH VERY DRY DOWNSLOPING
WINDS OFF THE LARAMIE RANGE. COULD BE LOOKING AT WIDESPREAD FIRE
WEATHER CONDITIONS FRIDAY.
.LONG TERM...(FRIDAY NIGHT THROUGH TUESDAY)
ISSUED AT 240 AM MDT WED JUL 23 2014
MODELS GENERALLY IN GOOD AGREEMENT THROUGH THE WEEKEND WITH THE
OVERALL PATTERN...SHOWING A POTENT UPPER LEVEL TROUGH DIGGING
SOUTHWARD OUT OF CANADA AND INTO THE GREAT LAKES REGION BY EARLY
SUNDAY. THIS WILL RESULT IN NORTHWEST FLOW OVER THE FORECAST AREA
AS THE STRONG UPPER LEVEL HIGH NUDGES SOUTHWARD AND THE
ASSOCIATED RIDGE AXIS WILL EXTEND NORTHWEST INTO THE GREAT BASIN
REGION. THERE ARE STILL DISCREPANCIES BETWEEN MODELS REGARDING
AVAILABLE LOW TO MIDLEVEL MOISTURE THROUGH THE WEEKEND AND INTO
EARLY NEXT WEEK. ALTHOUGH A SERIES OF COOL FRONTS ARE EXPECTED TO
PUSH SOUTHWARD ACROSS THE FORECAST AREA BEGINNING FRIDAY
NIGHT...THE LACK OF ANY DEFINED DISTURBANCES IS CREATING QUITE A
BIT OF UNCERTAINTY WITH TSTORM CHANCES INTO MONDAY. CURRENT 00Z
MODELS ARE BEGINNING TO TREND DRIER...AS THE NORTHWEST FLOW
RESULTS IN A BIT MORE STABILITY THAN PREVIOUSLY EXPECTED...NUDGING
THE MONSOON MOISTURE FURTHER SOUTH INTO THE FOUR CORNERS REGION
AND COLORADO. STARTED TO LOWER POP FOR THIS WEEKEND ACROSS MOST OF
THE AREA...ESPECIALLY FURTHER NORTH SINCE THE ECMWF IS NOW
TRENDING DRIER AS WELL. CURRENT SOUNDINGS SHOW TOO MUCH DRY AIR
ALOFT...SUPPRESSING ANY CONVECTION THAT DOES FORM. AFTER ANOTHER
WARM DAY ON SATURDAY...EXPECT TEMPERATURES TO LOWER BELOW NORMAL
ON SUNDAY WITH HIGHS IN THE 70S TO MID 80S UNDER COOL EAST TO
NORTHEAST FLOW.
CONDITIONS BECOME A LITTLE MORE INTERESTING AFTER MONDAY AS BOTH
THE GFS AND ECMWF SHOW SHORTWAVE ENERGY MOVING CLOCKWISE AROUND
THE MAIN UPPER LEVEL HIGH AND INTO WYOMING. INCREASED POP LATE MONDAY
THROUGH WEDNESDAY...MAINLY IN THE AFTERNOON AND EVENINGS. BOTH THE
GFS AND ECMWF ARE ON THE AGGRESSIVE SIDE WITH A HIGHER COVERAGE OF
SHOWERS AND TSTORMS...AT LEAST SCATTERED DURING THE AFTERNOON...AS
THE SHORTWAVE ENERGY PUSHES ACROSS EASTERN WYOMING BY WEDNESDAY.
KEPT TEMPERATURES A FEW DEGREES BELOW NORMAL DUE TO EASTERLY
UPSLOPE FLOW AND 700MB TEMPERATURES LOWERING TO BELOW 10C.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z THURSDAY AFTERNOON)
VFR EXPECTED OVERALL FOR ALL AERODROMES THROUGH THURSDAY. ISOLATED
SHOWERS AND TSTRMS OVER THE PLAINS THIS AFTERNOON AND EVENING WITH
ASSOCIATED MVFR VSBYS BUT LOOKING TOO ISOLATED TO MENTION IN
INDIVIDUAL TAFS.
&&
.FIRE WEATHER...
ISSUED AT 300 AM MDT WED JUL 23 2014
DRY CONDITIONS ACROSS WESTERN CARBON COUNTY AGAIN TODAY. A COLD
FRONT GENERALLY ALONG A LINE FROM CASPER TO LARAMIE WILL SEPARATE
RELATIVELY MOIST AIR EAST OF THE FRONT FROM THE REALLY DRY AIR TO
THE WEST. WETTING RAINS ARE LIKELY IN THE EASTERN SECTOR TODAY AND
TONIGHT WITH EXCELLENT OVERNIGHT RH RECOVERIES. CONDITIONS CHANGE
FOR THURSDAY THOUGH AS THE FRONT BEGINS TO MOVE EAST AGAIN AND
WINDS BEGIN TO PICK UP WEST OF THE LARAMIE RANGE. CRITICAL FIRE
WEATHER CONDITIONS FROM GUSTY WINDS AND LOW HUMIDITIES EARLY
THURSDAY AFTERNOON. TO COMPLICATE THE CONDITIONS MORE...WE HAVE
THE POSSIBILITY OF DRY THUNDERSTORMS WEST OF THE LARAMIE RANGE
THAT COULD CREATE SOME FIRE STARTS THURSDAY AFTERNOON. A FIRE
WEATHER WATCH HAS BEEN ISSUED FOR FWZ 301 FOR THURSDAY LATE
MORNING THROUGH THE AFTERNOON. DRY AND WINDY CONDITIONS TO
CONTINUE INTO SATURDAY FOR MORE WIDESPREAD FIRE WEATHER CONDITIONS
ACROSS SOUTHEAST WYOMING.
&&
.CYS WATCHES/WARNINGS/ADVISORIES...
WY...FIRE WEATHER WATCH FROM THURSDAY MORNING THROUGH THURSDAY
AFTERNOON FOR WYZ301.
NE...NONE.
&&
$$
UPDATE...SML
SHORT TERM...CLAYCOMB
LONG TERM...TJT
AVIATION...RE
FIRE WEATHER...CLAYCOMB