Forecast Discussions mentioning any of
"HRRR" "RAP" "RR" "RUC13" "RUC" received at GSD on 07/13/15
AREA FORECAST DISCUSSION
NWS PHOENIX AZ
143 PM MST SAT JUL 11 2015
.UPDATE...AVIATION AND FIRE WEATHER DISCUSSIONS...
&&
.SYNOPSIS...LITTLE CHANGE IN THE WEATHER PATTERN IS FORECAST THE
NEXT SEVERAL DAYS. DRY WEATHER WITH NEAR NORMAL TEMPERATURES ARE
EXPECTED IN SOUTHEAST CALIFORNIA AND SOUTHWEST ARIZONA...WITH A
THREAT OF AFTERNOON AND EVENING MOUNTAIN THUNDERSTORMS IN EASTERN
ARIZONA...GENERALLY EAST OF PHOENIX.
&&
.DISCUSSION.../ISSUED AT 840 AM MST 11 JULY/...
TODAY AND TONIGHT...SOME BIG CHANGES HAVE OCCURRED IN THE PAST 24
HOURS WITH REGARDS TO THE DISTRIBUTION OF MONSOON MOISTURE. FOR THE
PAST 2 DAYS MOST OF THE MOISTURE WAS CONTAINED IN SOUTHEAST AZ WITH
THE DRY LINE WAVERING BETWEEN PHOENIX AND TUCSON. THIS MORNINGS
PHOENIX SOUNDING NOW SHOWS THE CENTRAL DESERTS IN THE MONSOON
SOUP...SO TO SPEAK. FOR EXAMPLE...THE 12Z FRIDAY PHOENIX SOUNDING
SHOWED A PRECIP WATER (PW) VALUE OF 0.69 INCHES AND AN 800 MB
DEWPOINT OF 0 DEGREES C. IN CONTRAST...ITS NOW 1.35 INCHES OF PW
WITH AN 800 MB DEWPOINT OF 13 DEG C. MONSOON MOISTURE WILL CONTINUE
TO SPREAD SLOWLY WEST AND NORTH THIS WEEKEND...COVERING THE ENTIRE
STATE BY MONDAY.
ADDITIONALLY...BOTH PHOENIX AND TUCSON SOUNDINGS SHOWED CONSIDERABLE
ML C.A.P.E.(500-1000 J/KG)...WITH LOW CONVECTIVE TRIGGER TEMPS
(GLOBE 78 DEG F... TUCSON 89 F...AND HILLTOP AT 5700 FEET 70
F)...AND SIGNIFICANT VERTICAL SHEAR PROFILES...BETTER IN SOUTHEAST
AZ. AT THE SAME TIME HOWEVER...SATELLITE IMAGERY SHOWED A WEAK
DISTURBANCE MOVING OUT OF NORTHEAST AZ FOLLOWED BY A SIGNIFICANT
UPPER LEVEL ANTI-CYCLONIC CIRCULATION FEATURE CONNECTED TO THE
SUBTROPICAL JET OFFSHORE NORTHERN BAJA.
STRONG ANTI-CYCLONIC CIRCULATION TENDS TO STABILIZE THE ATMOSPHERE A
BIT...BUT WORKING AGAINST STRONG AFTERNOON THERMODYNAMICS TODAY WITH
A EARLY START TO MOUNTAIN CONVECTION. EVEN THOUGH THE POTENTIAL
ENERGY HAS INCREASED OVER THE LOWER DESERTS BETWEEN PHOENIX AND CASA
GRANDE...WE STILL THINK STORMS WILL BE RELEGATED TO THE HIGHER
TERRAIN NORTHEAST THROUGH SOUTHEAST OF PHOENIX. PERHAPS EARLY
EVENING CONVECTIVE OUTFLOWS ON THE LOWER DESERTS ARE POSSIBLE.
ALSO BECAUSE OF THE MODERATE VERTICAL WIND SHEAR PROFILES...SOME
CONVECTION IN SOUTHERN GILA COUNTY ZONE 24 MAY BECOME ORGANIZED WITH
HAIL AND STRONG GUSTY SURFACE WINDS.
OTHERWISE CURRENT FORECASTS LOOK OK. NO UPDATES PLANNED TODAY.
.PREVIOUS DISCUSSION...511 AM MST...
UNSEASONABLY STRONG UPPER LOW OVER NRN CA/WRN NV CONTINUED TO WEAKEN
AND LIFT NEWD EARLY THIS MORNING...MEANWHILE THE SWLY FLOW AHEAD OF
IT REMAINED STRONG ENOUGH OVER THE DESERT SOUTHWEST TO CONFINE
MOISTURE AND CONVECTION TO FAR ERN AND SERN AZ...MAINLY AREAS EAST
OF PHOENIX. IR IMAGERY AT 2 AM SHOWED CLEAR SKIES WEST OF PHOENIX
WITH PARTLY CLOUDY SKIES PRESENT FROM PHOENIX EAST. A COUPLE OF
INTERESTING THINGS TO NOTE...DESPITE THE CONTINUED PRESENCE OF
RELATIVELY DRY SOUTHWEST FLOW ALOFT OVER THE AREA AS SEEN IN THE
LATEST 00Z PLOT DATA...MOISTURE DID INCREASE IN THE PHOENIX AREA
DURING THE DAY YESTERDAY AND THE PHOENIX RAOB SHOWED PWAT UP TO 1.35
INCHES...WHICH WAS HIGHER THAN TUCSON WHICH REPORTED 1.21 INCHES.
ALSO...FRI EVENING SURFACE DEWPOINTS OVER THE CENTRAL DESERTS HAD
CLIMBED INTO THE LOW TO MID 50S...A RISE OF MORE THAN 20 DEGREES
OVER THE PAST 24 HOURS. SO...DESPITE THE SOUTHWEST FLOW ALOFT WITH A
VERY LAMINAR UPPER STREAMLINE FIELD AND NO SIGNIFICANT DISTURBANCES
MOVING THROUGH THE FLOW...AROUND MIDNIGHT ISOLATED SHOWERS/STORMS
STARTED TO DEVELOP OVER THE NORTH VALLEY...NEAR NEW RIVER...AND THEY
MOVED QUICKLY TO THE NORTH/NORTHEAST. LATEST HRRR SUGGESTS THESE
STORMS WILL WEAKEN AND MOVE OUT OF THE AREA WITHIN THE NEXT 1-2
HOURS LEAVING PARTLY CLOUDY OR MOSTLY CLEAR SKIES BEHIND FOR THE
REST OF TONIGHT.
FOR THE WEEKEND GUIDANCE REMAINS CONSISTENT THAT THE GRADUALLY
WEAKENING TROFFING TO OUR NORTHWEST WILL ALLOW THE MAIN UPPER HIGH
TO BUILD BACK WESTWARD...ALLOWING HEIGHTS TO RISE AND TEMPS TO CLIMB
BACK TOWARDS NORMAL READINGS. STILL...THE MAIN HIGH CENTER REMAINS
SUPPRESSED WELL TO THE EAST/SOUTHEAST OF ARIZONA AND AS SUCH
STEERING FLOW REMAINS SOUTH/SOUTHWESTERLY. AS SUCH WE ARE STILL
EXPECTED CONVECTION TO BE CONFINED PRIMARILY TO HIGHER TERRAIN AREAS
TO THE EAST OF PHOENIX...MAINLY AREAS OF SOUTHERN GILA COUNTY AS
WELL AS EASTERN PORTIONS OF ZONE 28 ACROSS NORTHWEST PINAL COUNTY.
ALL AREAS WEST OF MARICOPA COUNTY SHOULD STAY GENLY CLEAR WITH POPS
LOW SINGLE DIGITS OR ZERO.
AS FOR THE UPCOMING WORK WEEK...MONDAY THROUGH FRIDAY...GUIDANCE
INCLUDING THE GFS AND ECMWF CONTINUE TO SUGGEST THAT TROFFING TO OUR
NORTHWEST...OVER THE NORTHWESTERN STATES...WILL REMAIN STRONG ENOUGH
TO KEEP THE MAIN UPPER HIGH SUPPRESSED TO OUR EAST AND SOUTHEAST.
THIS WILL RESULT IN A CONTINUED SOUTHWESTERLY FLOW ACROSS MOST OF
OUR AREA THROUGH THE PERIOD. MOISTURE/INSTABILITY/CAPE WILL BE
MINIMAL FROM PHOENIX WESTWARD EACH DAY AND CONVECTION WILL REMAIN
CONFINED PRIMARILY TO HIGHER TERRAIN AREAS EAST AND SOUTHEAST OF
PHOENIX. WE ARE LOOKING AT A VERY LOW GRADE MONSOON FOR THE DURATION
OF THE FORECAST PERIOD. HIGH TEMPERATURES WILL CLIMB SLIGHTLY ABOVE
NORMAL EACH DAY WITH HOTTER DESERTS REACHING NEAR 110 DEGREES.
DESPITE H5 HEIGHTS STAYING MOSTLY AT OR BELOW 591DM EACH DAY...THE
DRIER AIR AND SUNNY AFTERNOONS WILL ALLOW TEMPS TO RISE A BIT ABOVE
SEASONAL NORMALS EACH DAY.
&&
.AVIATION...
SOUTH-CENTRAL ARIZONA INCLUDING KPHX...KIWA...AND KSDL...SOUTHEAST
CALIFORNIA AND SOUTHWEST ARIZONA INCLUDING KIPL AND KBLH...
ANOTHER AFTERNOON WITH BREEZY SOUTH-SOUTHWESTERLY WINDS FOR THE
PHOENIX AREA AIR FIELDS. EXPECTING A WESTERLY DIRECTION THROUGH EARLY
EVENING BUT WIND GUSTS SHOULD BE AT OR BELOW 20 KT. INCREASED MID AND
HIGH CLOUDS WILL PERSIST THROUGH THE AFTERNOON AND EVENING
HOURS...WITH EXPECTED THUNDERSTORMS TO THE EAST OF PHOENIX.
AVIATION DISCUSSION NOT UPDATED FOR AMENDED TAFS.
&&
.FIRE WEATHER...
TUESDAY THROUGH SATURDAY...
THE UPPER LEVEL FLOW PATTERN WILL SHIFT SLIGHTLY AS THE SUB-TROPICAL
HIGH SHIFTS WESTWARD AND REESTABLISHES ITSELF JUST TO THE EAST OF THE
DESERT SOUTHWEST NEXT WEEK. THIS WILL LEAD TO WARMING TEMPERATURES
AND LIKELY SOME MOISTURE RETURN INTO EASTERN AND POSSIBLY CENTRAL
ARIZONA. THUNDERSTORM CHANCES WILL BE LIMITED TO HIGHER TERRAIN
LOCATIONS NORTH AND EAST OF PHOENIX. AFTERNOON MINIMUM HUMIDITY
LEVELS IN A 10-15 PERCENT RANGE WILL BE PRESENT ACROSS THE LOWER
DESERTS THROUGHOUT THE WEEK. WINDS WILL BE BREEZY AND MOSTLY OUT OF
THE SOUTHWEST EACH AFTERNOON WITH GUSTS UP TO 20 MPH.
&&
.SPOTTER INFORMATION STATEMENT...
SPOTTERS ARE ENCOURAGED TO REPORT ANY SIGNIFICANT WEATHER CONDITIONS
ACCORDING TO STANDARD OPERATING PROCEDURES.
&&
.PSR WATCHES/WARNINGS/ADVISORIES...
AZ...NONE.
CA...NONE.
&&
$$
VISIT US ON FACEBOOK...TWITTER...AND AT WEATHER.GOV/PHOENIX
DISCUSSION...VASQUEZ/CB
AVIATION...DEWEY
FIRE WEATHER...DEWEY
AREA FORECAST DISCUSSION
NWS PHOENIX AZ
840 AM MST SAT JUL 11 2015
.SYNOPSIS...LITTLE CHANGE IN THE WEATHER PATTERN IS FORECAST THE
NEXT SEVERAL DAYS. DRY WEATHER WITH NEAR NORMAL TEMPERATURES ARE
EXPECTED IN SOUTHEAST CALIFORNIA AND SOUTHWEST ARIZONA...WITH A
THREAT OF AFTERNOON AND EVENING MOUNTAIN THUNDERSTORMS IN EASTERN
ARIZONA...GENERALLY EAST OF PHOENIX.
&&
.DISCUSSION...
TODAY AND TONIGHT...SOME BIG CHANGES HAVE OCCURRED IN THE PAST 24
HOURS WITH REGARDS TO THE DISTRIBUTION OF MONSOON MOISTURE. FOR THE
PAST 2 DAYS MOST OF THE MOISTURE WAS CONTAINED IN SOUTHEAST AZ WITH
THE DRY LINE WAVERING BETWEEN PHOENIX AND TUCSON. THIS MORNINGS
PHOENIX SOUNDING NOW SHOWS THE CENTRAL DESERTS IN THE MONSOON
SOUP...SO TO SPEAK. FOR EXAMPLE...THE 12Z FRIDAY PHOENIX SOUNDING
SHOWED A PRECIP WATER (PW) VALUE OF 0.69 INCHES AND AN 800 MB
DEWPOINT OF 0 DEGREES C. IN CONTRAST...ITS NOW 1.35 INCHES OF PW
WITH AN 800 MB DEWPOINT OF 13 DEG C. MONSOON MOISTURE WILL CONTINUE
TO SPREAD SLOWLY WEST AND NORTH THIS WEEKEND...COVERING THE ENTIRE
STATE BY MONDAY.
ADDITIONALLY...BOTH PHOENIX AND TUCSON SOUNDINGS SHOWED CONSIDERABLE
ML C.A.P.E.(500-1000 J/KG)...WITH LOW CONVECTIVE TRIGGER TEMPS
(GLOBE 78 DEG F... TUCSON 89 F...AND HILLTOP AT 5700 FEET 70
F)...AND SIGNIFICANT VERTICAL SHEAR PROFILES...BETTER IN SOUTHEAST
AZ. AT THE SAME TIME HOWEVER...SATELLITE IMAGERY SHOWED A WEAK
DISTURBANCE MOVING OUT OF NORTHEAST AZ FOLLOWED BY A SIGNIFICANT
UPPER LEVEL ANTI-CYCLONIC CIRCULATION FEATURE CONNECTED TO THE
SUBTROPICAL JET OFFSHORE NORTHERN BAJA.
STRONG ANTI-CYCLONIC CIRCULATION TENDS TO STABILIZE THE ATMOSPHERE A
BIT...BUT WORKING AGAINST STRONG AFTERNOON THERMODYNAMICS TODAY WITH
A EARLY START TO MOUNTAIN CONVECTION. EVEN THOUGH THE POTENTIAL
ENERGY HAS INCREASED OVER THE LOWER DESERTS BETWEEN PHOENIX AND CASA
GRANDE...WE STILL THINK STORMS WILL BE RELEGATED TO THE HIGHER
TERRAIN NORTHEAST THROUGH SOUTHEAST OF PHOENIX. PERHAPS EARLY
EVENING CONVECTIVE OUTFLOWS ON THE LOWER DESERTS ARE POSSIBLE.
ALSO BECAUSE OF THE MODERATE VERTICAL WIND SHEAR PROFILES...SOME
CONVECTION IN SOUTHERN GILA COUNTY ZONE 24 MAY BECOME ORGANIZED WITH
HAIL AND STRONG GUSTY SURFACE WINDS.
OTHERWISE CURRENT FORECASTS LOOK OK. NO UPDATES PLANNED TODAY.
.PREVIOUS DISCUSSION...511 AM MST...
UNSEASONABLY STRONG UPPER LOW OVER NRN CA/WRN NV CONTINUED TO WEAKEN
AND LIFT NEWD EARLY THIS MORNING...MEANWHILE THE SWLY FLOW AHEAD OF
IT REMAINED STRONG ENOUGH OVER THE DESERT SOUTHWEST TO CONFINE
MOISTURE AND CONVECTION TO FAR ERN AND SERN AZ...MAINLY AREAS EAST
OF PHOENIX. IR IMAGERY AT 2 AM SHOWED CLEAR SKIES WEST OF PHOENIX
WITH PARTLY CLOUDY SKIES PRESENT FROM PHOENIX EAST. A COUPLE OF
INTERESTING THINGS TO NOTE...DESPITE THE CONTINUED PRESENCE OF
RELATIVELY DRY SOUTHWEST FLOW ALOFT OVER THE AREA AS SEEN IN THE
LATEST 00Z PLOT DATA...MOISTURE DID INCREASE IN THE PHOENIX AREA
DURING THE DAY YESTERDAY AND THE PHOENIX RAOB SHOWED PWAT UP TO 1.35
INCHES...WHICH WAS HIGHER THAN TUCSON WHICH REPORTED 1.21 INCHES.
ALSO...FRI EVENING SURFACE DEWPOINTS OVER THE CENTRAL DESERTS HAD
CLIMBED INTO THE LOW TO MID 50S...A RISE OF MORE THAN 20 DEGREES
OVER THE PAST 24 HOURS. SO...DESPITE THE SOUTHWEST FLOW ALOFT WITH A
VERY LAMINAR UPPER STREAMLINE FIELD AND NO SIGNIFICANT DISTURBANCES
MOVING THROUGH THE FLOW...AROUND MIDNIGHT ISOLATED SHOWERS/STORMS
STARTED TO DEVELOP OVER THE NORTH VALLEY...NEAR NEW RIVER...AND THEY
MOVED QUICKLY TO THE NORTH/NORTHEAST. LATEST HRRR SUGGESTS THESE
STORMS WILL WEAKEN AND MOVE OUT OF THE AREA WITHIN THE NEXT 1-2
HOURS LEAVING PARTLY CLOUDY OR MOSTLY CLEAR SKIES BEHIND FOR THE
REST OF TONIGHT.
FOR THE WEEKEND GUIDANCE REMAINS CONSISTENT THAT THE GRADUALLY
WEAKENING TROFFING TO OUR NORTHWEST WILL ALLOW THE MAIN UPPER HIGH
TO BUILD BACK WESTWARD...ALLOWING HEIGHTS TO RISE AND TEMPS TO CLIMB
BACK TOWARDS NORMAL READINGS. STILL...THE MAIN HIGH CENTER REMAINS
SUPPRESSED WELL TO THE EAST/SOUTHEAST OF ARIZONA AND AS SUCH
STEERING FLOW REMAINS SOUTH/SOUTHWESTERLY. AS SUCH WE ARE STILL
EXPECTED CONVECTION TO BE CONFINED PRIMARILY TO HIGHER TERRAIN AREAS
TO THE EAST OF PHOENIX...MAINLY AREAS OF SOUTHERN GILA COUNTY AS
WELL AS EASTERN PORTIONS OF ZONE 28 ACROSS NORTHWEST PINAL COUNTY.
ALL AREAS WEST OF MARICOPA COUNTY SHOULD STAY GENLY CLEAR WITH POPS
LOW SINGLE DIGITS OR ZERO.
AS FOR THE UPCOMING WORK WEEK...MONDAY THROUGH FRIDAY...GUIDANCE
INCLUDING THE GFS AND ECMWF CONTINUE TO SUGGEST THAT TROFFING TO OUR
NORTHWEST...OVER THE NORTHWESTERN STATES...WILL REMAIN STRONG ENOUGH
TO KEEP THE MAIN UPPER HIGH SUPPRESSED TO OUR EAST AND SOUTHEAST.
THIS WILL RESULT IN A CONTINUED SOUTHWESTERLY FLOW ACROSS MOST OF
OUR AREA THROUGH THE PERIOD. MOISTURE/INSTABILITY/CAPE WILL BE
MINIMAL FROM PHOENIX WESTWARD EACH DAY AND CONVECTION WILL REMAIN
CONFINED PRIMARILY TO HIGHER TERRAIN AREAS EAST AND SOUTHEAST OF
PHOENIX. WE ARE LOOKING AT A VERY LOW GRADE MONSOON FOR THE DURATION
OF THE FORECAST PERIOD. HIGH TEMPERATURES WILL CLIMB SLIGHTLY ABOVE
NORMAL EACH DAY WITH HOTTER DESERTS REACHING NEAR 110 DEGREES.
DESPITE H5 HEIGHTS STAYING MOSTLY AT OR BELOW 591DM EACH DAY...THE
DRIER AIR AND SUNNY AFTERNOONS WILL ALLOW TEMPS TO RISE A BIT ABOVE
SEASONAL NORMALS EACH DAY.
&&
.AVIATION...
SOUTH-CENTRAL ARIZONA INCLUDING KPHX...KIWA...AND KSDL...SOUTHEAST
CALIFORNIA AND SOUTHWEST ARIZONA INCLUDING KIPL AND KBLH...
INCREASED MID AND HIGH CLOUDS WILL BE PRESENT THROUGH MUCH OF THE
DAY BEFORE GRADUALLY CLEARING TONIGHT. WILL AGAIN SEE SOME ISOLATED
SHOWERS AND THUNDERSTORMS TODAY ACROSS HIGHER TERRAIN AREAS OF
CENTRAL AND EASTERN ARIZONA...BUT STAYING AWAY FROM THE PHOENIX
TERMINALS. LIGHT AND DIURNALLY DRIVEN WINDS WILL BE THE RULE THROUGH
THE PERIOD.
AVIATION DISCUSSION NOT UPDATED FOR AMENDED TAFS.
&&
.FIRE WEATHER...
MONDAY THROUGH FRIDAY...
THE UPPER LEVEL FLOW PATTERN WILL SHIFT SLIGHTLY AS THE SUB-TROPICAL
HIGH SHIFTS WESTWARD AND REESTABLISHES ITSELF JUST TO THE EAST OF
THE DESERT SOUTHWEST NEXT WEEK. THIS WILL LEAD TO WARMING
TEMPERATURES AND LIKELY AT LEAST SOME MOISTURE RETURN INTO EASTERN
AND POSSIBLY CENTRAL ARIZONA. THUNDERSTORM CHANCES WILL BE LIMITED
TO HIGHER TERRAIN LOCATIONS NORTH AND EAST OF PHOENIX. AFTERNOON
MINIMUM HUMIDITY LEVELS IN A 10-15 PERCENT RANGE WILL BE PRESENT
ACROSS THE LOWER DESERTS THROUGHOUT THE WEEK. WINDS WILL BE BREEZY
AND MOSTLY OUT OF THE SOUTHWEST EACH AFTERNOON WITH GUSTS UP TO 20
MPH.
&&
.SPOTTER INFORMATION STATEMENT...
SPOTTERS ARE ENCOURAGED TO REPORT ANY SIGNIFICANT WEATHER CONDITIONS
ACCORDING TO STANDARD OPERATING PROCEDURES.
&&
.PSR WATCHES/WARNINGS/ADVISORIES...
AZ...NONE.
CA...NONE.
&&
$$
VISIT US ON FACEBOOK...TWITTER...AND AT WEATHER.GOV/PHOENIX
DISCUSSION...VASQUEZ/CB
AVIATION...KUHLMAN
FIRE WEATHER...KUHLMAN
AREA FORECAST DISCUSSION
NWS PHOENIX AZ
511 AM MST SAT JUL 11 2015
.UPDATE...UPDATED AVIATION AND FIRE WEATHER DISCUSSIONS...
&&
.SYNOPSIS...LITTLE CHANGE IN THE WEATHER PATTERN IS FORECAST THE
NEXT SEVERAL DAYS. DRY WEATHER WITH NEAR NORMAL TEMPERATURES ARE
EXPECTED IN SOUTHEAST CALIFORNIA AND SOUTHWEST ARIZONA...WITH A
THREAT OF AFTERNOON AND EVENING MOUNTAIN THUNDERSTORMS IN EASTERN
ARIZONA...GENERALLY EAST OF PHOENIX.
&&
.DISCUSSION...
UNSEASONABLY STRONG UPPER LOW OVER NRN CA/WRN NV CONTINUED TO WEAKEN
AND LIFT NEWD EARLY THIS MORNING...MEANWHILE THE SWLY FLOW AHEAD OF
IT REMAINED STRONG ENOUGH OVER THE DESERT SOUTHWEST TO CONFINE
MOISTURE AND CONVECTION TO FAR ERN AND SERN AZ...MAINLY AREAS EAST
OF PHOENIX. IR IMAGERY AT 2 AM SHOWED CLEAR SKIES WEST OF PHOENIX
WITH PARTLY CLOUDY SKIES PRESENT FROM PHOENIX EAST. A COUPLE OF
INTERESTING THINGS TO NOTE...DESPITE THE CONTINUED PRESENCE OF
RELATIVELY DRY SOUTHWEST FLOW ALOFT OVER THE AREA AS SEEN IN THE
LATEST 00Z PLOT DATA...MOISTURE DID INCREASE IN THE PHOENIX AREA
DURING THE DAY YESTERDAY AND THE PHOENIX RAOB SHOWED PWAT UP TO 1.35
INCHES...WHICH WAS HIGHER THAN TUCSON WHICH REPORTED 1.21 INCHES.
ALSO...FRI EVENING SURFACE DEWPOINTS OVER THE CENTRAL DESERTS HAD
CLIMBED INTO THE LOW TO MID 50S...A RISE OF MORE THAN 20 DEGREES
OVER THE PAST 24 HOURS. SO...DESPITE THE SOUTHWEST FLOW ALOFT WITH A
VERY LAMINAR UPPER STREAMLINE FIELD AND NO SIGNIFICANT DISTURBANCES
MOVING THROUGH THE FLOW...AROUND MIDNIGHT ISOLATED SHOWERS/STORMS
STARTED TO DEVELOP OVER THE NORTH VALLEY...NEAR NEW RIVER...AND THEY
MOVED QUICKLY TO THE NORTH/NORTHEAST. LATEST HRRR SUGGESTS THESE
STORMS WILL WEAKEN AND MOVE OUT OF THE AREA WITHIN THE NEXT 1-2
HOURS LEAVING PARTLY CLOUDY OR MOSTLY CLEAR SKIES BEHIND FOR THE
REST OF TONIGHT.
FOR THE WEEKEND GUIDANCE REMAINS CONSISTENT THAT THE GRADUALLY
WEAKENING TROFFING TO OUR NORTHWEST WILL ALLOW THE MAIN UPPER HIGH
TO BUILD BACK WESTWARD...ALLOWING HEIGHTS TO RISE AND TEMPS TO CLIMB
BACK TOWARDS NORMAL READINGS. STILL...THE MAIN HIGH CENTER REMAINS
SUPPRESSED WELL TO THE EAST/SOUTHEAST OF ARIZONA AND AS SUCH
STEERING FLOW REMAINS SOUTH/SOUTHWESTERLY. AS SUCH WE ARE STILL
EXPECTED CONVECTION TO BE CONFINED PRIMARILY TO HIGHER TERRAIN AREAS
TO THE EAST OF PHOENIX...MAINLY AREAS OF SOUTHERN GILA COUNTY AS
WELL AS EASTERN PORTIONS OF ZONE 28 ACROSS NORTHWEST PINAL COUNTY.
ALL AREAS WEST OF MARICOPA COUNTY SHOULD STAY GENLY CLEAR WITH POPS
LOW SINGLE DIGITS OR ZERO.
AS FOR THE UPCOMING WORK WEEK...MONDAY THROUGH FRIDAY...GUIDANCE
INCLUDING THE GFS AND ECMWF CONTINUE TO SUGGEST THAT TROFFING TO OUR
NORTHWEST...OVER THE NORTHWESTERN STATES...WILL REMAIN STRONG ENOUGH
TO KEEP THE MAIN UPPER HIGH SUPPRESSED TO OUR EAST AND SOUTHEAST.
THIS WILL RESULT IN A CONTINUED SOUTHWESTERLY FLOW ACROSS MOST OF
OUR AREA THROUGH THE PERIOD. MOISTURE/INSTABILITY/CAPE WILL BE
MINIMAL FROM PHOENIX WESTWARD EACH DAY AND CONVECTION WILL REMAIN
CONFINED PRIMARILY TO HIGHER TERRAIN AREAS EAST AND SOUTHEAST OF
PHOENIX. WE ARE LOOKING AT A VERY LOW GRADE MONSOON FOR THE DURATION
OF THE FORECAST PERIOD. HIGH TEMPERATURES WILL CLIMB SLIGHTLY ABOVE
NORMAL EACH DAY WITH HOTTER DESERTS REACHING NEAR 110 DEGREES.
DESPITE H5 HEIGHTS STAYING MOSTLY AT OR BELOW 591DM EACH DAY...THE
DRIER AIR AND SUNNY AFTERNOONS WILL ALLOW TEMPS TO RISE A BIT ABOVE
SEASONAL NORMALS EACH DAY.
&&
.AVIATION...
SOUTH-CENTRAL ARIZONA INCLUDING KPHX...KIWA...AND KSDL...SOUTHEAST
CALIFORNIA AND SOUTHWEST ARIZONA INCLUDING KIPL AND KBLH...
INCREASED MID AND HIGH CLOUDS WILL BE PRESENT THROUGH MUCH OF THE
DAY BEFORE GRADUALLY CLEARING TONIGHT. WILL AGAIN SEE SOME ISOLATED
SHOWERS AND THUNDERSTORMS TODAY ACROSS HIGHER TERRAIN AREAS OF
CENTRAL AND EASTERN ARIZONA...BUT STAYING AWAY FROM THE PHOENIX
TERMINALS. LIGHT AND DIURNALLY DRIVEN WINDS WILL BE THE RULE THROUGH
THE PERIOD.
AVIATION DISCUSSION NOT UPDATED FOR AMENDED TAFS.
&&
.FIRE WEATHER...
MONDAY THROUGH FRIDAY...
THE UPPER LEVEL FLOW PATTERN WILL SHIFT SLIGHTLY AS THE SUB-TROPICAL
HIGH SHIFTS WESTWARD AND REESTABLISHES ITSELF JUST TO THE EAST OF
THE DESERT SOUTHWEST NEXT WEEK. THIS WILL LEAD TO WARMING
TEMPERATURES AND LIKELY AT LEAST SOME MOISTURE RETURN INTO EASTERN
AND POSSIBLY CENTRAL ARIZONA. THUNDERSTORM CHANCES WILL BE LIMITED
TO HIGHER TERRAIN LOCATIONS NORTH AND EAST OF PHOENIX. AFTERNOON
MINIMUM HUMIDITY LEVELS IN A 10-15 PERCENT RANGE WILL BE PRESENT
ACROSS THE LOWER DESERTS THROUGHOUT THE WEEK. WINDS WILL BE BREEZY
AND MOSTLY OUT OF THE SOUTHWEST EACH AFTERNOON WITH GUSTS UP TO 20
MPH.
&&
.SPOTTER INFORMATION STATEMENT...
SPOTTERS ARE ENCOURAGED TO REPORT ANY SIGNIFICANT WEATHER CONDITIONS
ACCORDING TO STANDARD OPERATING PROCEDURES.
&&
.PSR WATCHES/WARNINGS/ADVISORIES...
AZ...NONE.
CA...NONE.
&&
$$
VISIT US ON FACEBOOK...TWITTER...AND AT WEATHER.GOV/PHOENIX
DISCUSSION...CB
AVIATION...KUHLMAN
FIRE WEATHER...KUHLMAN
AREA FORECAST DISCUSSION
NWS PHOENIX AZ
200 AM MST SAT JUL 11 2015
.SYNOPSIS...LITTLE CHANGE IN THE WEATHER PATTERN IS FORECAST THE
NEXT SEVERAL DAYS. DRY WEATHER WITH NEAR NORMAL TEMPERATURES ARE
EXPECTED IN SOUTHEAST CALIFORNIA AND SOUTHWEST ARIZONA...WITH A
THREAT OF AFTERNOON AND EVENING MOUNTAIN THUNDERSTORMS IN EASTERN
ARIZONA...GENERALLY EAST OF PHOENIX.
&&
.DISCUSSION...
UNSEASONABLY STRONG UPPER LOW OVER NRN CA/WRN NV CONTINUED TO WEAKEN
AND LIFT NEWD EARLY THIS MORNING...MEANWHILE THE SWLY FLOW AHEAD OF
IT REMAINED STRONG ENOUGH OVER THE DESERT SOUTHWEST TO CONFINE
MOISTURE AND CONVECTION TO FAR ERN AND SERN AZ...MAINLY AREAS EAST
OF PHOENIX. IR IMAGERY AT 2 AM SHOWED CLEAR SKIES WEST OF PHOENIX
WITH PARTLY CLOUDY SKIES PRESENT FROM PHOENIX EAST. A COUPLE OF
INTERESTING THINGS TO NOTE...DESPITE THE CONTINUED PRESENCE OF
RELATIVELY DRY SOUTHWEST FLOW ALOFT OVER THE AREA AS SEEN IN THE
LATEST 00Z PLOT DATA...MOISTURE DID INCREASE IN THE PHOENIX AREA
DURING THE DAY YESTERDAY AND THE PHOENIX RAOB SHOWED PWAT UP TO 1.35
INCHES...WHICH WAS HIGHER THAN TUCSON WHICH REPORTED 1.21 INCHES.
ALSO...FRI EVENING SURFACE DEWPOINTS OVER THE CENTRAL DESERTS HAD
CLIMBED INTO THE LOW TO MID 50S...A RISE OF MORE THAN 20 DEGREES
OVER THE PAST 24 HOURS. SO...DESPITE THE SOUTHWEST FLOW ALOFT WITH A
VERY LAMINAR UPPER STREAMLINE FIELD AND NO SIGNIFICANT DISTURBANCES
MOVING THROUGH THE FLOW...AROUND MIDNIGHT ISOLATED SHOWERS/STORMS
STARTED TO DEVELOP OVER THE NORTH VALLEY...NEAR NEW RIVER...AND THEY
MOVED QUICKLY TO THE NORTH/NORTHEAST. LATEST HRRR SUGGESTS THESE
STORMS WILL WEAKEN AND MOVE OUT OF THE AREA WITHIN THE NEXT 1-2
HOURS LEAVING PARTLY CLOUDY OR MOSTLY CLEAR SKIES BEHIND FOR THE
REST OF TONIGHT.
FOR THE WEEKEND GUIDANCE REMAINS CONSISTENT THAT THE GRADUALLY
WEAKENING TROFFING TO OUR NORTHWEST WILL ALLOW THE MAIN UPPER HIGH
TO BUILD BACK WESTWARD...ALLOWING HEIGHTS TO RISE AND TEMPS TO CLIMB
BACK TOWARDS NORMAL READINGS. STILL...THE MAIN HIGH CENTER REMAINS
SUPPRESSED WELL TO THE EAST/SOUTHEAST OF ARIZONA AND AS SUCH
STEERING FLOW REMAINS SOUTH/SOUTHWESTERLY. AS SUCH WE ARE STILL
EXPECTED CONVECTION TO BE CONFINED PRIMARILY TO HIGHER TERRAIN AREAS
TO THE EAST OF PHOENIX...MAINLY AREAS OF SOUTHERN GILA COUNTY AS
WELL AS EASTERN PORTIONS OF ZONE 28 ACROSS NORTHWEST PINAL COUNTY.
ALL AREAS WEST OF MARICOPA COUNTY SHOULD STAY GENLY CLEAR WITH POPS
LOW SINGLE DIGITS OR ZERO.
AS FOR THE UPCOMING WORK WEEK...MONDAY THROUGH FRIDAY...GUIDANCE
INCLUDING THE GFS AND ECMWF CONTINUE TO SUGGEST THAT TROFFING TO OUR
NORTHWEST...OVER THE NORTHWESTERN STATES...WILL REMAIN STRONG ENOUGH
TO KEEP THE MAIN UPPER HIGH SUPPRESSED TO OUR EAST AND SOUTHEAST.
THIS WILL RESULT IN A CONTINUED SOUTHWESTERLY FLOW ACROSS MOST OF
OUR AREA THROUGH THE PERIOD. MOISTURE/INSTABILITY/CAPE WILL BE
MINIMAL FROM PHOENIX WESTWARD EACH DAY AND CONVECTION WILL REMAIN
CONFINED PRIMARILY TO HIGHER TERRAIN AREAS EAST AND SOUTHEAST OF
PHOENIX. WE ARE LOOKING AT A VERY LOW GRADE MONSOON FOR THE DURATION
OF THE FORECAST PERIOD. HIGH TEMPERATURES WILL CLIMB SLIGHTLY ABOVE
NORMAL EACH DAY WITH HOTTER DESERTS REACHING NEAR 110 DEGREES.
DESPITE H5 HEIGHTS STAYING MOSTLY AT OR BELOW 591DM EACH DAY...THE
DRIER AIR AND SUNNY AFTERNOONS WILL ALLOW TEMPS TO RISE A BIT ABOVE
SEASONAL NORMALS EACH DAY.
&&
.PREVIOUS DISCUSSION...
THROUGH NEXT FRIDAY...ITS UNUSUAL THAT A LARGE AMOUNT OF MOMENTUM
AND ENERGY IN THE WEST COAST TROF HAS BEEN ABLE TO CONTROL THE FLOW
PATTERN OVER AZ IN MID JULY. THIS HAS PREVENTED THE SUBTROPICAL HIGH
PRESSURE SYSTEM FROM SEASONALLY BULGING TO AZ THE PAST SEVERAL
DAYS...INCLUDING NEXT WEEK. THEREFORE A PERSISTENCE FORECAST IS IN
ORDER FOR OUR AREA...SOUTHEAST CA TO SOUTH CENTRAL AZ...WHERE MONSOON
MOISTURE WILL BE DRAWN NORTH INTO SOUTHEAST AZ PROVIDING A DAILY
THREAT OF AFTERNOON/EVENING THUNDERSTORMS OVER THE MOUNTAINS OF
SOUTHERN GILA COUNTY ZONE 24.
&&
.AVIATION...
SOUTH-CENTRAL ARIZONA INCLUDING KPHX...KIWA...AND KSDL...SOUTHEAST
CALIFORNIA AND SOUTHWEST ARIZONA INCLUDING KIPL AND KBLH...
WINDS SHOULD GRADUALLY TAPER OFF THIS EVENING AND OVERNIGHT AS THE
BOUNDARY LAYER STABILIZES WITH THE LOSS OF DAYTIME
HEATING...EVENTUALLY BECOMING LIGHT/DIURNAL IN NATURE AROUND 12Z. NOT
ANTICIPATING ANY STORMS AT ANY OF THE TERMINALS...NOR ANY IMPACTS
FROM DISTANT STORMS.
AVIATION DISCUSSION NOT UPDATED FOR AMENDED TAFS.
&&
.FIRE WEATHER...
SUNDAY THROUGH FRIDAY...
THE UPPER LEVEL FLOW PATTERN WILL SHIFT SLIGHTLY AS THE SUB-TROPICAL
HIGH SHIFTS WESTWARD AND REESTABLISHES ITSELF OVER THE DESERT
SOUTHWEST STARTING SUNDAY. THIS WILL LEAD TO WARMING TEMPERATURES AND
LIKELY AT LEAST SOME MOISTURE RETURN INTO EASTERN AND POSSIBLY
CENTRAL ARIZONA. THUNDERSTORM CHANCES WILL MOSTLY BE LIMITED TO
HIGHER TERRAIN LOCATIONS NORTH AND EAST OF PHOENIX WITH ONLY SLIM
CHANCES OF ANY ACTIVITY OVER THE DESERTS. AFTERNOON HUMIDITY LEVELS
IN A 15-20 PERCENT RANGE THROUGH MONDAY WILL LOWER SOMEWHAT GOING
INTO THE MIDDLE OF NEXT WEEK AS TEMPERATURES RISE TO SLIGHTLY ABOVE
NORMAL LEVELS. WINDS WILL BE BREEZY AND MOSTLY OUT OF THE SOUTHWEST
EACH AFTERNOON WITH GUSTS UP TO 20 MPH.
&&
.SPOTTER INFORMATION STATEMENT...
SPOTTERS ARE ENCOURAGED TO REPORT ANY SIGNIFICANT WEATHER CONDITIONS
ACCORDING TO STANDARD OPERATING PROCEDURES.
&&
.PSR WATCHES/WARNINGS/ADVISORIES...
AZ...NONE.
CA...NONE.
&&
$$
VISIT US ON FACEBOOK...TWITTER...AND AT WEATHER.GOV/PHOENIX
DISCUSSION...CB
AVIATION...LEINS
FIRE WEATHER...KUHLMAN
AREA FORECAST DISCUSSION
NWS RENO NV
230 PM PDT SAT JUL 11 2015
.SYNOPSIS...
DRIER SOUTHWEST FLOW ALOFT THIS WEEKEND WILL BRING DECREASING
THUNDERSTORM COVERAGE AND SLOWLY WARMING TEMPERATURES. DRY WEATHER
IS EXPECTED NEXT WEEK WITH TEMPERATURES WARMING TO AROUND AVERAGE BY
TUESDAY OR WEDNESDAY.
&&
.SHORT TERM...
NO MAJOR MODIFICATIONS WERE MADE TO THE PREVIOUS FORECAST. THE
ONLY MINOR CHANGES WERE TO EXTEND THE AREA OF SLIGHT CHANCES OF
THUNDERSTORMS DOWN TO THE SIERRA CREST OF MONO COUNTY FOR THIS
EVENING. THE HRRR AND NAM ARE FAVORING SOME CHANCES OF A
THUNDERSTORM AND CUMULUS DEVELOPMENT ON VISIBLE IMAGERY SUPPORTS
AT LEAST A 15% COVERAGE.
OTHERWISE, ONLY LOOKING AT SLIGHT CHANCES OF A THUNDERSTORM AGAIN
SUNDAY AFTERNOON FROM EASTERN MONO COUNTY NORTHEAST THROUGH
EASTERN PERSHING COUNTY. THEN, DRIER SOUTHWESTERLY FLOW DEVELOPS
MONDAY ONWARD. NAM SEEMS TO BE OVER-CONVECTING MONDAY AFTERNOON
IN MONO COUNTY, BUT MAY SEE A STRAY SHOWER/THUNDERSTORM; KEPT
CHANCES AROUND 10%. THE THERMAL AND PRESSURE GRADIENTS WILL ONLY
BE ABLE TO SUPPORT AFTERNOON GUSTS FROM 20 TO 25 MPH EACH
AFTERNOON WITH THE MORE TYPICAL AFTERNOON ZEPHYR PATTERN.
TEMPERATURES WILL WARM BACK INTO THE MID/UPPER 80S FOR WESTERN
NEVADA BY MONDAY WITH MID/UPPER 70S IN THE SIERRA. BOYD
.LONG TERM...TUESDAY THROUGH SATURDAY...
FEW CHANGES IN THE EXTENDED FORECAST WITH A DRY AND MORE STABLE
PATTERN IN STORE FOR NEXT WEEK. HIGH TEMPERATURES WILL REMAIN NEAR
AVERAGE VALUES FOR THIS TIME OF YEAR WITH UPPER 80S TO LOWER 90S
ACROSS WESTERN NEVADA TO START THE WEEK WITH GRADUAL WARMING INTO
THE WEEKEND. UPPER 70S TO LOW 80S CAN BE EXPECTED OVER THE SIERRA
VALLEYS NEXT WEEK.
INSTABILITY WILL DEVELOP ACROSS THE SIERRA MAINLY THROUGH ALPINE AND
MONO COUNTIES EACH DAY WITH MAINLY CUMULUS DEVELOPMENT IN THESE
AREAS TUESDAY THROUGH THURSDAY. THE LIMITING FACTOR LOOKS TO BE
ENOUGH DEEP LAYER MOISTURE FOR STORM DEVELOPMENT. AT THIS POINT WILL
KEEP CHANCES BELOW 15% FOR THESE AREAS. INSTABILITY AND MOISTURE
LOOKS MORE FAVORABLE HEADING INTO THE WEEKEND BUT WILL KEEP MENTION
OF STORMS OUT OF THE FORECAST FOR NOW AS UNCERTAINTY STILL IS
SIZABLE IN TERMS OF RESOLVING THE UPPER LEVEL PATTERN. BOTH THE
GFS AND EC ATTEMPT A CUT-OFF LOW OFF THE SOUTHERN CALIFORNIA COAST
WHICH LEAVES THE SIERRA IN MORE OF A TROUGH PATTERN TOWARDS THE
WEEKEND IN THE GFS WHILE THE EC DEVELOPS A SHORTWAVE RIDGE. THIS IS
ALMOST THE REVERSE OF WHAT EACH MODEL HAS BEEN SHOWING IN THEIR
RESPECTIVE LAST FEW CYCLES. NEEDLESS TO SAY, ENSEMBLES SPREADS ARE
LARGE WILL MAINTAIN PERSISTENCE WITH THE CURRENT FORECAST. FUENTES
&&
.AVIATION...
ISOLATED STORMS ARE POSSIBLE THROUGH 03Z MAINLY FOR AREAS IN WEST
CENTRAL NEVADA EAST OF KNFL, BUT OVERALL AVIATION-RELATED IMPACTS
WILL BE REDUCED COMPARED TO RECENT DAYS. FOR SUNDAY, ISOLATED
STORMS ARE POSSIBLE NORTH OF A FALLON-SUSANVILLE LINE BUT THE MAIN
TERMINALS SHOULD REMAIN FREE OF CONVECTION. SW-W WINDS WITH GUSTS
20- 25 KT ARE PROBABLE, MAINLY BTWN 21Z-04Z. TF
&&
.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 SAN JOAQUIN VALLEY - HANFORD CA
200 PM PDT SAT JUL 11 2015
.SYNOPSIS...
RESIDUAL SHOWERS AND THUNDERSTORMS OVER THE SIERRA CREST WILL
CONTINUE THROUGH TODAY. ELSEWHERE BELOW NORMAL TEMPERATURES AND DRY
CONDITIONS REMAIN DUE TO A SOUTHWEST FLOW ALOFT OVER THE REGION.
WARMING AND DRYING TRENDS WILL CONTINUE ACROSS THE AREA OVER THE
NEXT WEEK.
&&
.DISCUSSION...
AS THE HIGH-RESOLUTION MODELS HAD FORECAST...MIDDAY SATELLITE LOOPS
SHOW CUMULUS CLOUDS DEVELOPING NOT ONLY ALONG THE SOUTHERN SIERRA
NEVADA BUT ALSO OVER THE DIABLO RANGE NEAR THE JUNCTION OF SAN
BENITO...MONTEREY AND FRESNO COUNTIES AND OVER /AND SOUTH OF/ THE
SAN EMIGDIO MOUNTAINS NEAR FRAZIER PARK. AS OF 20Z /1300 PDT/ NO
LIGHTNING HAD BEEN DETECTED IN THE WFO HANFORD WARNING/FORECAST AREA
BUT THE HRRR SUGGESTED THAT CONVECTION MIGHT NOT BEGIN BEFORE 22Z
/1500 PDT/.
THE MODELS ARE IN GENERAL AGREEMENT WITH AN UPPER-LEVEL TROUGH OVER
CALIFORNIA THROUGH THE MIDDLE OF NEXT WEEK WITH A SERIES OF SHORT-
WAVES MOVING THROUGH THE TROUGH. THIS WILL KEEP A SOUTHWEST FLOW
ALOFT OVER CENTRAL CALIFORNIA FOR DRY WEATHER AND CONTINUED BELOW
NORMAL TEMPERATURES THE NEXT FEW DAYS.
FOR THE LATTER HALF OF NEXT WEEK...THE MEDIUM-RANGE MODELS BUILD AN
UPPER-LEVEL RIDGE OVER THE SOUTHERN U.S. WESTWARD...LIFTING THE
TROUGH NORTHWARD AND WARMING TEMPERATURES ABOVE NORMAL BY THURSDAY
WHEN CENTRAL AND SOUTHERN SAN JOAQUIN VALLEY HIGHS ARE FORECAST TO
BE AROUND 100. HOWEVER...THE GFS AND ECMWF DIFFER CONCERNING AN
UPPER-LEVEL TROUGH THAT IS FORECAST TO MOVE THROUGH THE PACIFIC
NORTHWEST TOWARD THE END OF NEXT WEEK...AND THE FORECAST HAS LITTLE
CHANGE IN TEMPERATURES FOR FRIDAY AND SATURDAY DUE TO THE MODEL
DIFFERENCES.
THE BIGGEST UNCERTAINTY CONCERNS TROPICAL DEPRESSION 5-E OFF THE
SOUTHWESTERN COAST OF MEXICO. THE MODELS SLOWLY LIFT THE SYSTEM...
WHICH WOULD BE NAMED DOLORES IF IT REACHES TROPICAL STORM
STRENGTH... NORTHWEST WITH THE ECMWF HAVING A MORE WESTERLY TRACK
THAN THE GFS. BY SATURDAY NIGHT...THE GFS HAS THE SYSTEM WEST OF THE
TIP OF BAJA CALIFORNIA WITH A SOUTHERLY FLOW OVER CALIFORNIA. IF THE
GFS IS CORRECT...AND THE EXTENDED GFS COULD EASILY CHANGE OVER THE
NEXT SEVERAL DAYS...COULD SEE TROPICAL MOISTURE MOVING INTO INTERIOR
CENTRAL CALIFORNIA FROM THE SOUTH. AT THIS POINT THERE IS LOW
CONFIDENCE IN THIS SOLUTION DUE TO THE DIFFERENCES BETWEEN THE GFS
AND THE ECMWF AND HAVE OPTED TO KEEP POPS MAINLY IN SINGLE DIGITS
NEXT SATURDAY.
&&
.AVIATION...
OTHER THAN AN ISOLATED THUNDERSTORM OR TWO ALONG THE COASTAL RANGES
WEST OF INTERSTATE 5 AND IN THE VICINITY OF FRAZIER PARK EARLY THIS
EVENING...ISOLATED THUNDERSTORMS WITH LOCAL MVFR CEILINGS CAN BE
EXPECTED ALONG THE SIERRA CREST UNTIL 06Z SUNDAY. OTHERWISE...VFR
CONDITIONS WILL PREVAIL THROUGHOUT THE CENTRAL CA INTERIOR DURING
THE NEXT 24 HOURS.
&&
.AIR QUALITY ISSUES...
NONE.
&&
.CERTAINTY...
THE LEVEL OF CERTAINTY FOR DAYS 1 AND 2 IS HIGH.
THE LEVEL OF CERTAINTY FOR DAYS 3 THROUGH 7 IS HIGH.
THIS INFORMATION IS PROVIDED AS PART OF A TRIAL PROJECT CONDUCTED
BY THE NATIONAL WEATHER SERVICE SAN JOAQUIN VALLEY - HANFORD.
CERTAINTY LEVELS INCLUDE LOW...MEDIUM...AND HIGH. PLEASE VISIT
WWW.WEATHER.GOV/HNX/CERTAINTY.PHP /ALL LOWER CASE/ FOR ADDITIONAL
INFORMATION AND/OR TO PROVIDE FEEDBACK.
&&
.CLIMATE...
RECORDS
SITE DATE HI_MAX:YEAR LO_MAX:YEAR HI_MIN:YEAR LO_MIN:YEAR
KFAT 07-11 110:1961 82:1888 78:2002 52:1974
KFAT 07-12 109:2012 82:1995 81:1999 54:1965
KFAT 07-13 110:1983 84:1932 83:1999 55:1903
KBFL 07-11 110:1961 83:1936 79:2002 51:1906
KBFL 07-12 113:1913 81:1995 80:1999 48:1914
KBFL 07-13 111:1908 87:1995 85:1999 46:1914
&&
.HNX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
PUBLIC...SANGER
AVN/FW...DURFEE
SYNOPSIS...ANDERSEN
WEATHER.GOV/HANFORD
AREA FORECAST DISCUSSION...UPDATED
NWS SAN JOAQUIN VALLEY - HANFORD CA
958 AM PDT SAT JUL 11 2015
.UPDATE...
ADDED SLIGHT CHANCE OF THUNDERSTORMS TO THE SAN EMIGDIO MOUNTAINSAND
TO THE DIABLO RANGE NEAR COALINGA THIS AFTERNOON AND EVENING.
.SYNOPSIS...
A LOW PRESSURE SYSTEM CONTINUES TO MOVE OUT OF THE REGION WITH
RESIDUAL SHOWERS AND THUNDERSTORMS IN THE HIGH COUNTRY OF THE SIERRA
WILL CONTINUE. BY SATURDAY...A DRY SOUTHWEST FLOW WILL THEN PREVAIL
BRINGING A WARMING TREND AND DRY CONDITIONS TO THE REGION.
&&
.DISCUSSION...
THIS MORNING/S HIGH-RESOLUTION MODELS...ARW/WRF-NMM/HRRR AND
NAM-12...ALL IN AGREEMENT WITH POSSIBLE CONVECTION OVER THE SAN
EMIGDIO MOUNTAINS NEAR FRAZIER PARK...AND OVER THE DIABLO RANGE
WEST OF COALINGA...THIS AFTERNOON AND EARLY EVENING. HRRR RADAR
FORECAST INDICATES BEST CHANCES FOR ISOLATED THUNDERSTORMS BETWEEN
22Z /1500 PDT/ THIS AFTERNOON AND 02Z SUNDAY /1900 PDT THIS
EVENING/. HAVE UPDATED THE FORECAST TO ADD SLIGHT CHANCE POPS FOR
THESE AREAS THIS AFTERNOON AND EVENING. OTHERWISE...NO CHANGES TO
THE FORECAST.
&&
.PREV DISCUSSION... /ISSUED 232 AM PDT SAT JUL 11 2015/
DISCUSSION...STILL A FEW SHOWERS AND THUNDERSTORMS BROKE OUT ON
FRIDAY AFTERNOON NEAR THE SIERRA CREST AND WITH THE WEAKENING LOW
PRESSURE SYSTEM LINGERING OVER THE REGION, THE THREAT OF
CONVECTION WILL CONTINUE FOR ANOTHER DAY OVER THE MOUNTAINS.
COOLER THAN NORMAL WEATHER WILL ALSO PREVAIL AS HEIGHTS REMAIN
RELATIVELY LOW FOR MID JULY. FOR THE NEXT FEW DAYS, LITTLE OVERALL
CHANGE IN THE PATTERN WILL OCCUR WITH THE REMAINING MOISTURE OVER
THE SIERRA GETTING PUSHED TO THE EAST WHILE A DRIER SOUTHWEST FLOW
CONTINUES. MODELS ARE IN GOOD AGREEMENT AT LEAST THROUGH MID WEEK
OF KEEPING A WEAK TROUGH PATTERN OVER CALIFORNIA AND THIS ALLOW
FOR A SLOW RETURN TO TEMPERATURES CLOSER TO NORMAL FOR JULY.
BY LATER IN THE WEEK MODELS BEGIN TO TREND TOWARDS A SOLUTION OF A
RIDGE OVER DESERT SOUTHWEST AND EAST PACIFIC AND TRANSITORY
TROUGHS WORKING EAST ALONG THE CANADIAN BORDER. THIS PATTERN WILL
NOT ALLOW THE MONSOON TO KICK BACK IN, THUS THE FORECAST REMAINS
DRY.
&&
.AVIATION...
LCL MVFR IN SHOWERS/THUNDERSTORMS OVER SIERRA NEVADA CREST BETWEEN
20Z AND 06Z SATURDAY. OTHERWISE...VFR CONDITIONS WILL PREVAIL
THROUGHOUT THE CENTRAL CA INTERIOR DURING THE NEXT 24 HOURS.
&&
.AIR QUALITY ISSUES...
NONE.
&&
.CERTAINTY...
THE LEVEL OF CERTAINTY FOR DAYS 1 AND 2 IS HIGH.
THE LEVEL OF CERTAINTY FOR DAYS 3 THROUGH 7 IS HIGH.
THIS INFORMATION IS PROVIDED AS PART OF A TRIAL PROJECT CONDUCTED
BY THE NATIONAL WEATHER SERVICE SAN JOAQUIN VALLEY - HANFORD.
CERTAINTY LEVELS INCLUDE LOW...MEDIUM...AND HIGH. PLEASE VISIT
WWW.WEATHER.GOV/HNX/CERTAINTY.PHP /ALL LOWER CASE/ FOR ADDITIONAL
INFORMATION AND/OR TO PROVIDE FEEDBACK.
&&
.CLIMATE...
RECORDS
SITE DATE HI_MAX:YEAR LO_MAX:YEAR HI_MIN:YEAR LO_MIN:YEAR
KFAT 07-11 110:1961 82:1888 78:2002 52:1974
KFAT 07-12 109:2012 82:1995 81:1999 54:1965
KFAT 07-13 110:1983 84:1932 83:1999 55:1903
KBFL 07-11 110:1961 83:1936 79:2002 51:1906
KBFL 07-12 113:1913 81:1995 80:1999 48:1914
KBFL 07-13 111:1908 87:1995 85:1999 46:1914
&&
.HNX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
PUBLIC...SANGER
AVN/FW...MOLINA
PREV DISCUSSION...DUDLEY
SYNOPSIS...DUDLEY
WEATHER.GOV/HANFORD
AREA FORECAST DISCUSSION
NWS PUEBLO CO
248 PM MDT SAT JUL 11 2015
.SHORT TERM...(THIS EVENING THROUGH SUNDAY)
ISSUED AT 247 PM MDT SAT JUL 11 2015
AN UPR HIGH CENTER IS OVR ERN TX TODAY AND IS EXPECTED TO SHIFT
WESTWARD OVR TX TONIGHT AND SUNDAY. THERE IS LIMITED MSTR OVR THE
AREA TODAY...BUT STILL ENOUGH FOR ISOLD SHOWERS/TSTMS MAINLY OVR AND
NR THE HYR TRRN. THE NAM KEEPS PCPN TIED TO THE HIGHER TRRN...
INCLUDING THE PALMER DVD...WHILE THE LATEST RUN OF THE HRRR IS
SHOWING THE POTENTIAL FOR A FEW STORMS TO MOVE OUT OVR THE I-25
CORRIDOR AND OVR BACA AND ERN LAS ANIMAS COUNTIES EARLY THIS
EVENING. SHOULD SEE MOST IF NOT ALL CONVECTION END BEFORE MIDNIGHT.
ON SUNDAY THE MSTR WL STILL BE LIMITED AND HIGH TEMPS SHOULD
GENERALLY BE A LITTLE ABOVE AVERAGE. THERE SHOULD AGAIN BE SOME
ISOLD SHOWERS AND TSTMS...MOSTLY OVR AND NR THE MTN AREAS.
.LONG TERM...(SUNDAY NIGHT THROUGH SATURDAY)
ISSUED AT 247 PM MDT SAT JUL 11 2015
GENERAL WEATHER PATTERN THROUGH THE EXTENDED PERIOD FAVORS NEAR NORMAL
TEMPERATURES AND BELOW NORMAL RAINFALL.
SUNDAY NIGHT...UPPER RIDGE CENTERED ACROSS THE SOUTHERN PLAINS.
ANY DIURNAL CONVECTION IS FORECAST TO WANE THROUGH THE EVENING
HOURS.
MONDAY...DURING THE DAY THE NORTHWEST US TROUGH IS FORECAST TO
EDGE EAST...AND MOISTURE ALONG THE PERIPHERY OF THE UPPER RIDGE
WILL BE IN WESTERN AND CENTRAL COLORADO DURING THE AFTERNOON AND
EVENING. WE HAVE LOW END SCATTERED TO ISOLATED POPS GOING AND THAT
SEEMS REASONABLE. WITH SOME MORE CLOUDS AND SHOWERS...HIGH
TEMPERATURES WILL BE A BIT LOWER ACROSS THE CWA...BUT IT WILL
STILL BE QUITE WARM...WITH SEASONAL HIGHS IN THE UPPER 80S TO 90S
PLAINS...70S AND 80S HIGH VALLEYS...AND 50S TO 70S MOUNTAINS.
MODELS SUGGEST CONVECTION WILL LINGER INTO THE OVERNIGHT.
TUESDAY...THE UPPER RIDGE IS FORECAST TO BE SHUNTED SOUTH SOME...AND
THE MOISTURE TAP FROM THE SUBTROPICS WILL STILL BE OVER THE CWA.
SO...ANOTHER ROUND OF ISOLATED TO SCATTERED AFTERNOON AND EVENING
SHOWERS AND STORMS WILL PERSIST. HIGH TEMPERATURES WILL BE SIMILAR
TO MONDAYS READINGS.
WEDNESDAY...A SHORTWAVE IS FORECAST TO EJECT OUT OF THE WESTERN
TROUGH BUT IT SHOULD BE CENTERED FAR TO OUR NORTH. STILL...ANOTHER
SHOT OF AFTERNOON AND EVENING SHOWERS AND STORMS WILL OCCUR WITH
THE MOISTURE IN PLACE AND SOME FORCING ALOFT.
THURSDAY THROUGH SATURDAY...AS THE NORTHERN SHORTWAVE PUSHES EAST
INTO THE UPPER MIDWEST AND GREAT LAKES...THE UPPER RIDGE WILL RETROGRADE
SOME TO THE WEST...AND THE ROCKIES WILL SEE ZONAL FLOW AND A
LITTLE MORE SETTLED WEATHER. DURING THE AFTERNOON AND EVENING
THERE WILL BE CHANCES FOR HIGHER ELEVATION SHOWERS AND STORMS.
TEMPERATURE WILL CONTINUE TO BE NEAR NORMAL FOR JULY.
OF COURSE...THERE IS ALWAYS THE THREAT FOR STRONGER STORMS TO
IMPACT BURN SCARS...SO THAT WILL BE CLOSELY WATCHED. -TLM-
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON)
ISSUED AT 247 PM MDT SAT JUL 11 2015
VFR CONDITIONS CAN BE EXPECTED AT THE TAF SITE TONIGHT THROUGH
SUNDAY. THERE IS A SMALL CHANCE THAT A TSTM COULD MOVE INTO THE
VCNTY OF KCOS OR KALS THIS EVENING. SUNDAY AFTERNOON KALS COULD SEE
A TSTM IN THE VCNTY BUT CHANCES ARE LOW.
&&
.PUB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...28
LONG TERM...TM
AVIATION...28
AREA FORECAST DISCUSSION
NWS GRAND JUNCTION CO
1138 AM MDT SAT JUL 11 2015
.UPDATE...
ISSUED AT 739 AM MDT SAT JUL 11 2015
SHOWERS AND THUNDERSTORMS ALREADY DEVELOPING TO OUR SOUTHWEST THIS
MORNING WITH LIGHTNING ACTIVITY PICKING UP IN THE VICINITY OF LAKE
POWELL ON EDGE ON WEAK WAVE LIFTING NORTHEAST. ECMWF AND RUC SEEMS
TO HAVE THE BEST HANDLE ON THIS MINOR RIPPLE LIFTING IT NORTHEAST
AND WEAKENING OVER THE NEXT FEW HOURS. A SECONDARY WAVE LOOKS TO
SPIN UP AROUND NOON...WITH MORE ACTIVITY LIFTING ACROSS MESA
COUNTY AND INTO THE NORTHWEST PORTIONS OF THE FORECAST AREA. HAVE
ADJUST POPS TO FIT CURRENT SITUATION AND BOOSTED VALUES UP A BIT
THIS AFTERNOON. NO OTHER CHANGES WERE MADE TO THE GRIDS.
&&
.SHORT TERM...(TODAY THROUGH SUNDAY)
ISSUED AT 400 AM MDT SAT JUL 11 2015
FORECAST PWATS REMAIN SOMEWHAT HIGH TODAY WITH VALUES OF AN INCH
OR JUST ABOVE FAVORED IN THE RAP AND NAM WHILE GFS AND SREF PUT
VALUES BETWEEN .75 TO .9 INCHES. THE LOCATION OF THE HIGH
PRESSURE OVER TX AND AND TROUGH OFF THE WEST COAST STILL LOOKS
FAVORABLE FOR MOISTURE TO CONTINUE TO ADVECT IN FROM THE SOUTH.
NAM12 AND GFS IN PRETTY GOOD AGREEMENT THAT CONVECTION WILL FIRE
IN THE FOUR CORNERS AROUND NOON AND OVERSPREAD THE AREA TO THE
NORTHEAST. THE JET STREAM IS LOCATED FROM SRN CALIF...UP THROUGH
LAS VEGAS AND CENTRAL UTAH WHICH WILL INCREASE ASCENT AND ALSO
DIVERGENCE ALOFT WHICH IS ALWAYS HELPFUL IN CONVECTION. STRONGER
STORMS AND SHOWERS THAT FORM WILL BRING HEAVY RAIN...SMALL HAIL
AND SOME GUSTY WINDS...SIMILAR TO WHAT WE`VE SEEN ALL WEEK. SOME
CONVECTION WILL CONTINUE THROUGH MIDNIGHT WITH VERY ISOLD
CONVECTION AFTER THAT.
THE TRICKY PART OF THE FORECAST IS SUNDAY. THE NAM PAINTS AN
ALMOST COMPLETELY DRY DAY FOR THE CWA WHILE THE GFS FAVORS THE SAN
JUANS AND AREAS SOUTH FOR MORE PRECIP. NOT SOLD ON NAM AS
AVAILABLE MOISTURE...THOUGH LOWER...WILL STILL REMAIN AND THOUGH
THE MOST ENERGETIC PART OF THE JET STREAM SHIFTS TO THE PLAIN
STATES...ENOUGH SUPPORT MAY ALLOW SOME RAIN TO FALL. WITH THAT IN
MIND...KEPT SCHC CONVECTION IN FORECAST FOR QUITE A BIT OF THE
FORECAST AREA. MIGHT BE A BIT MUCH BUT WE CAN TRIM THE FORECAST AS
NEWER MODELS COME IN.
TEMPS START TO RISE BUT WILL REMAIN BELOW CLIMO.
.LONG TERM...(SUNDAY NIGHT THROUGH FRIDAY)
ISSUED AT 400 AM MDT SAT JUL 11 2015
MODELS ASSERT THAT THE LARGE SCALE PATTERN WILL REMAIN LARGELY
UNCHANGED DURING THE EARLY PART OF THE COMING WEEK. CONSEQUENTLY
...EXPECT THE MONSOONAL SURGE WILL CONTINUE AS SUBTROPICAL
MOISTURE IS DRAWN NORTHEASTWARD ACROSS THE AREA BETWEEN HIGH
PRESSURE OVER THE SOUTHERN PLAINS AND A TROUGH OF LOW PRESSURE
OVER THE WEST COAST. THE MOISTURE LADEN AIR WILL FUEL MAINLY
AFTERNOON AND EVENING SHOWERS AND THUNDERSTORMS FAVORING THE
MOUNTAINS. NOCTURNAL STORMS ARE POSSIBLE DURING THIS PERIOD AS
MORE SUBTLE FEATURES NOT WELL HANDLED BY LARGE SCALE MODELS MAY
COME INTO PLAY.
MODELS POINT TO A SHIFT IN THE PATTERN AT MIDWEEK AS ENERGY
EJECTED FROM THE WEST COAST TROUGH MOVES EASTWARD OVER THE
NORTHERN ROCKIES FLATTENING THE RIDGE. AS THIS OCCURS HIGH
PRESSURE OVER THE SOUTHERN PLAINS WILL EXPAND WESTWARD CUTTING OFF
THE INFLUX OF MOISTURE. DRIER AIR IN WESTERLY FLOW WILL ERODE THE
MOISTURE OVER THE AREA DURING THE LATTER PART OF THE WEEK BRINGING
A DECREASE IN AFTERNOON/EVENING SHOWERS AND THUNDERSTORMS AS EARLY
AS WEDNESDAY. MODELS DIFFER IN TIMING WITH GFS FASTER WITH THIS
EVOLUTION...BUT BY THE END OF THE WEEK MODELS WERE IN AGREEMENT
WITH GREATLY REDUCED MOIST CONVECTION.
TEMPERATURES WILL REMAIN SUPPRESSED BY CLOUDS AND SHOWER ACTIVITY
DURING THE EARLY PART OF THE WEEK SO EXPECT BELOW NORMAL VALUES
TO CONTINUE. DRIER AIR TRANSLATES INTO GREATER SOLAR INSOLATION
DURING THE LATTER HALF OF THE COMING WEEK AND AFTERNOON HIGHS WILL
TREND UPWARD AS RESULT.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON)
ISSUED AT 1136 AM MDT SAT JUL 11 2015
SCATTERED SHOWERS AND THUNDERSTORMS WILL CONTINUE ACROSS WESTERN
COLORADO AND EASTERN UTAH THROUGH 02Z THIS EVENING. ACTIVITY WILL
DIMINISH AFTER 02Z. GUSTY WINDS TO NEAR 45 KTS...SMALL HAIL AND
BRIEF HEAVY RAINFALL WILL ACCOMPANY THE FAST MOVING STORMS. EXPECT
ILS CIGS NEAR SHOWERS AND THUNDERSTORMS WITH MOUNTAIN TOPS
BECOMING OBSCURED. AWAY FROM SHOWERS...VFR CONDS WILL PREVAIL.
&&
.GJT WATCHES/WARNINGS/ADVISORIES...
CO...NONE.
UT...NONE.
&&
$$
UPDATE...JDC
SHORT TERM...TGR
LONG TERM...NL
AVIATION...JDC
AREA FORECAST DISCUSSION
NWS GRAND JUNCTION CO
759 AM MDT SAT JUL 11 2015
.UPDATE...
ISSUED AT 739 AM MDT SAT JUL 11 2015
SHOWERS AND THUNDERSTORMS ALREADY DEVELOPING TO OUR SOUTHWEST THIS
MORNING WITH LIGHTNING ACTIVITY PICKING UP IN THE VICINITY OF LAKE
POWELL ON EDGE ON WEAK WAVE LIFTING NORTHEAST. ECMWF AND RUC SEEMS
TO HAVE THE BEST HANDLE ON THIS MINOR RIPPLE LIFTING IT NORTHEAST
AND WEAKENING OVER THE NEXT FEW HOURS. A SECONDARY WAVE LOOKS TO
SPIN UP AROUND NOON...WITH MORE ACTIVITY LIFTING ACROSS MESA
COUNTY AND INTO THE NORTHWEST PORTIONS OF THE FORECAST AREA. HAVE
ADJUST POPS TO FIT CURRENT SITUATION AND BOOSTED VALUES UP A BIT
THIS AFTERNOON. NO OTHER CHANGES WERE MADE TO THE GRIDS.
&&
.SHORT TERM...(TODAY THROUGH SUNDAY)
ISSUED AT 400 AM MDT SAT JUL 11 2015
FORECAST PWATS REMAIN SOMEWHAT HIGH TODAY WITH VALUES OF AN INCH
OR JUST ABOVE FAVORED IN THE RAP AND NAM WHILE GFS AND SREF PUT
VALUES BETWEEN .75 TO .9 INCHES. THE LOCATION OF THE HIGH
PRESSURE OVER TX AND AND TROUGH OFF THE WEST COAST STILL LOOKS
FAVORABLE FOR MOISTURE TO CONTINUE TO ADVECT IN FROM THE SOUTH.
NAM12 AND GFS IN PRETTY GOOD AGREEMENT THAT CONVECTION WILL FIRE
IN THE FOUR CORNERS AROUND NOON AND OVERSPREAD THE AREA TO THE
NORTHEAST. THE JET STREAM IS LOCATED FROM SRN CALIF...UP THROUGH
LAS VEGAS AND CENTRAL UTAH WHICH WILL INCREASE ASCENT AND ALSO
DIVERGENCE ALOFT WHICH IS ALWAYS HELPFUL IN CONVECTION. STRONGER
STORMS AND SHOWERS THAT FORM WILL BRING HEAVY RAIN...SMALL HAIL
AND SOME GUSTY WINDS...SIMILAR TO WHAT WE`VE SEEN ALL WEEK. SOME
CONVECTION WILL CONTINUE THROUGH MIDNIGHT WITH VERY ISOLD
CONVECTION AFTER THAT.
THE TRICKY PART OF THE FORECAST IS SUNDAY. THE NAM PAINTS AN
ALMOST COMPLETELY DRY DAY FOR THE CWA WHILE THE GFS FAVORS THE SAN
JUANS AND AREAS SOUTH FOR MORE PRECIP. NOT SOLD ON NAM AS
AVAILABLE MOISTURE...THOUGH LOWER...WILL STILL REMAIN AND THOUGH
THE MOST ENERGETIC PART OF THE JET STREAM SHIFTS TO THE PLAIN
STATES...ENOUGH SUPPORT MAY ALLOW SOME RAIN TO FALL. WITH THAT IN
MIND...KEPT SCHC CONVECTION IN FORECAST FOR QUITE A BIT OF THE
FORECAST AREA. MIGHT BE A BIT MUCH BUT WE CAN TRIM THE FORECAST AS
NEWER MODELS COME IN.
TEMPS START TO RISE BUT WILL REMAIN BELOW CLIMO.
.LONG TERM...(SUNDAY NIGHT THROUGH FRIDAY)
ISSUED AT 400 AM MDT SAT JUL 11 2015
MODELS ASSERT THAT THE LARGE SCALE PATTERN WILL REMAIN LARGELY
UNCHANGED DURING THE EARLY PART OF THE COMING WEEK. CONSEQUENTLY
...EXPECT THE MONSOONAL SURGE WILL CONTINUE AS SUBTROPICAL
MOISTURE IS DRAWN NORTHEASTWARD ACROSS THE AREA BETWEEN HIGH
PRESSURE OVER THE SOUTHERN PLAINS AND A TROUGH OF LOW PRESSURE
OVER THE WEST COAST. THE MOISTURE LADEN AIR WILL FUEL MAINLY
AFTERNOON AND EVENING SHOWERS AND THUNDERSTORMS FAVORING THE
MOUNTAINS. NOCTURNAL STORMS ARE POSSIBLE DURING THIS PERIOD AS
MORE SUBTLE FEATURES NOT WELL HANDLED BY LARGE SCALE MODELS MAY
COME INTO PLAY.
MODELS POINT TO A SHIFT IN THE PATTERN AT MIDWEEK AS ENERGY
EJECTED FROM THE WEST COAST TROUGH MOVES EASTWARD OVER THE
NORTHERN ROCKIES FLATTENING THE RIDGE. AS THIS OCCURS HIGH
PRESSURE OVER THE SOUTHERN PLAINS WILL EXPAND WESTWARD CUTTING OFF
THE INFLUX OF MOISTURE. DRIER AIR IN WESTERLY FLOW WILL ERODE THE
MOISTURE OVER THE AREA DURING THE LATTER PART OF THE WEEK BRINGING
A DECREASE IN AFTERNOON/EVENING SHOWERS AND THUNDERSTORMS AS EARLY
AS WEDNESDAY. MODELS DIFFER IN TIMING WITH GFS FASTER WITH THIS
EVOLUTION...BUT BY THE END OF THE WEEK MODELS WERE IN AGREEMENT
WITH GREATLY REDUCED MOIST CONVECTION.
TEMPERATURES WILL REMAIN SUPPRESSED BY CLOUDS AND SHOWER ACTIVITY
DURING THE EARLY PART OF THE WEEK SO EXPECT BELOW NORMAL VALUES
TO CONTINUE. DRIER AIR TRANSLATES INTO GREATER SOLAR INSOLATION
DURING THE LATTER HALF OF THE COMING WEEK AND AFTERNOON HIGHS WILL
TREND UPWARD AS RESULT.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SUNDAY MORNING)
ISSUED AT 400 AM MDT SAT JUL 11 2015
VFR CONDITIONS WILL PREVAIL ACROSS THE AREA BEFORE MIDDAY...THOUGH
A WEAK DISTURBANCE UPSTREAM MAY GET A FEW SHOWERS AND
THUNDERSTORMS STARTED OVER THE SAN JUAN/S PRIOR TO NOON. DAYTIME
HEATING COMBINED WITH MONSOON MOISTURE WILL FUEL SCATTERED
THUNDERSTORMS DURING THE AFTERNOON AND INTO THE EARLY EVENING.
THIS ACTIVITY WILL RESULT IN AREAS OF MOUNTAIN OBSCURATION ALONG
WITH OUTFLOW WINDS TO 40 MPH. CHANCES OF STORMS LOWERING CIGS
BELOW ILS BREAKPOINTS ARE LOW WITH OUTFLOW WINDS IMPACTING AIRPORT
OPERATIONS MORE LIKELY. SHOWERS AND THUNDERSTORMS WILL LARGELY
DIMINISH AFTER SUNSET.
&&
.GJT WATCHES/WARNINGS/ADVISORIES...
CO...NONE.
UT...NONE.
&&
$$
UPDATE...JDC
SHORT TERM...TGR
LONG TERM...NL
AVIATION...NL
AREA FORECAST DISCUSSION
NWS GRAND JUNCTION CO
400 AM MDT SAT JUL 11 2015
.SHORT TERM...(TODAY THROUGH SUNDAY)
ISSUED AT 400 AM MDT SAT JUL 11 2015
FORECAST PWATS REMAIN SOMEWHAT HIGH TODAY WITH VALUES OF AN INCH
OR JUST ABOVE FAVORED IN THE RAP AND NAM WHILE GFS AND SREF PUT
VALUES BETWEEN .75 TO .9 INCHES. THE LOCATION OF THE HIGH
PRESSURE OVER TX AND AND TROUGH OFF THE WEST COAST STILL LOOKS
FAVORABLE FOR MOISTURE TO CONTINUE TO ADVECT IN FROM THE SOUTH.
NAM12 AND GFS IN PRETTY GOOD AGREEMENT THAT CONVECTION WILL FIRE
IN THE FOUR CORNERS AROUND NOON AND OVERSPREAD THE AREA TO THE
NORTHEAST. THE JET STREAM IS LOCATED FROM SRN CALIF...UP THROUGH
LAS VEGAS AND CENTRAL UTAH WHICH WILL INCREASE ASCENT AND ALSO
DIVERGENCE ALOFT WHICH IS ALWAYS HELPFUL IN CONVECTION. STRONGER
STORMS AND SHOWERS THAT FORM WILL BRING HEAVY RAIN...SMALL HAIL
AND SOME GUSTY WINDS...SIMILAR TO WHAT WE`VE SEEN ALL WEEK. SOME
CONVECTION WILL CONTINUE THROUGH MIDNIGHT WITH VERY ISOLD
CONVECTION AFTER THAT.
THE TRICKY PART OF THE FORECAST IS SUNDAY. THE NAM PAINTS AN
ALMOST COMPLETELY DRY DAY FOR THE CWA WHILE THE GFS FAVORS THE SAN
JUANS AND AREAS SOUTH FOR MORE PRECIP. NOT SOLD ON NAM AS
AVAILABLE MOISTURE...THOUGH LOWER...WILL STILL REMAIN AND THOUGH
THE MOST ENERGETIC PART OF THE JET STREAM SHIFTS TO THE PLAIN
STATES...ENOUGH SUPPORT MAY ALLOW SOME RAIN TO FALL. WITH THAT IN
MIND...KEPT SCHC CONVECTION IN FORECAST FOR QUITE A BIT OF THE
FORECAST AREA. MIGHT BE A BIT MUCH BUT WE CAN TRIM THE FORECAST AS
NEWER MODELS COME IN.
TEMPS START TO RISE BUT WILL REMAIN BELOW CLIMO.
.LONG TERM...(SUNDAY NIGHT THROUGH FRIDAY)
ISSUED AT 400 AM MDT SAT JUL 11 2015
MODELS ASSERT THAT THE LARGE SCALE PATTERN WILL REMAIN LARGELY
UNCHANGED DURING THE EARLY PART OF THE COMING WEEK. CONSEQUENTLY
...EXPECT THE MONSOONAL SURGE WILL CONTINUE AS SUBTROPICAL
MOISTURE IS DRAWN NORTHEASTWARD ACROSS THE AREA BETWEEN HIGH
PRESSURE OVER THE SOUTHERN PLAINS AND A TROUGH OF LOW PRESSURE
OVER THE WEST COAST. THE MOISTURE LADEN AIR WILL FUEL MAINLY
AFTERNOON AND EVENING SHOWERS AND THUNDERSTORMS FAVORING THE
MOUNTAINS. NOCTURNAL STORMS ARE POSSIBLE DURING THIS PERIOD AS
MORE SUBTLE FEATURES NOT WELL HANDLED BY LARGE SCALE MODELS MAY
COME INTO PLAY.
MODELS POINT TO A SHIFT IN THE PATTERN AT MIDWEEK AS ENERGY
EJECTED FROM THE WEST COAST TROUGH MOVES EASTWARD OVER THE
NORTHERN ROCKIES FLATTENING THE RIDGE. AS THIS OCCURS HIGH
PRESSURE OVER THE SOUTHERN PLAINS WILL EXPAND WESTWARD CUTTING OFF
THE INFLUX OF MOISTURE. DRIER AIR IN WESTERLY FLOW WILL ERODE THE
MOISTURE OVER THE AREA DURING THE LATTER PART OF THE WEEK BRINGING
A DECREASE IN AFTERNOON/EVENING SHOWERS AND THUNDERSTORMS AS EARLY
AS WEDNESDAY. MODELS DIFFER IN TIMING WITH GFS FASTER WITH THIS
EVOLUTION...BUT BY THE END OF THE WEEK MODELS WERE IN AGREEMENT
WITH GREATLY REDUCED MOIST CONVECTION.
TEMPERATURES WILL REMAIN SUPPRESSED BY CLOUDS AND SHOWER ACTIVITY
DURING THE EARLY PART OF THE WEEK SO EXPECT BELOW NORMAL VALUES
TO CONTINUE. DRIER AIR TRANSLATES INTO GREATER SOLAR INSOLATION
DURING THE LATTER HALF OF THE COMING WEEK AND AFTERNOON HIGHS WILL
TREND UPWARD AS RESULT.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SUNDAY MORNING)
ISSUED AT 400 AM MDT SAT JUL 11 2015
VFR CONDITIONS WILL PREVAIL ACROSS THE AREA BEFORE MIDDAY...THOUGH
A WEAK DISTURBANCE UPSTREAM MAY GET A FEW SHOWERS AND
THUNDERSTORMS STARTED OVER THE SAN JUAN/S PRIOR TO NOON. DAYTIME
HEATING COMBINED WITH MONSOON MOISTURE WILL FUEL SCATTERED
THUNDERSTORMS DURING THE AFTERNOON AND INTO THE EARLY EVENING.
THIS ACTIVITY WILL RESULT IN AREAS OF MOUNTAIN OBSCURATION ALONG
WITH OUTFLOW WINDS TO 40 MPH. CHANCES OF STORMS LOWERING CIGS
BELOW ILS BREAKPOINTS ARE LOW WITH OUTFLOW WINDS IMPACTING AIRPORT
OPERATIONS MORE LIKELY. SHOWERS AND THUNDERSTORMS WILL LARGELY
DIMINISH AFTER SUNSET.
&&
.GJT WATCHES/WARNINGS/ADVISORIES...
CO...NONE.
UT...NONE.
&&
$$
SHORT TERM...TGR
LONG TERM...NL
AVIATION...NL
AREA FORECAST DISCUSSION
NWS PUEBLO CO
1116 PM MDT FRI JUL 10 2015
.SHORT TERM...(THIS EVENING THROUGH SATURDAY)
ISSUED AT 247 PM MDT FRI JUL 10 2015
DRIER AIR HAS MOVED OVR MUCH OF THE AREA TODAY...AND SO FAR ONLY A
FEW STORMS HAVE DEVELOPED OVR THE SRN SANGRES AND THE SWRN CO MTNS.
THE HRRR SHOWS ONLY SOME ISOLD PCPN ACRS THE FORECAST AREA THIS
EVENING...THEN ENDING WITH THE LOSS OF HEATING. THE NAM IS QUITE
SIMILAR. LATE TONIGHT THE NAM AND GFS SHOW A LEE TROF OVR THE FAR
SERN PLAINS...AND EARLY SAT MORNING THE NAM SHOWS THE POTENTIAL FOR
SOME LIGHT PCPN OVR OR NR KIOWA COUNTY...WHILE THE GFS IS DRY. WL
GO WITH A DRY SOLUTION FOR NOW.
ON SAT AN UPR HIGH CENTER WL MOVE WESTWARD INTO ERN TX...WITH AN UPR
TROF BEING ALONG THE WEST COAST. THERE WL BE LIMITED MSTR OVR THE
FORECAST AREA ON SAT AND AS A RESULT...JUST SOME ISOLD SHOWERS AND
TSTMS ARE EXPECTED OVR AND NR THE MTN AREAS. HIGH TEMPS ON SAT
SHOULD BE AROUND AVERAGE.
.LONG TERM...(SATURDAY NIGHT THROUGH FRIDAY)
ISSUED AT 247 PM MDT FRI JUL 10 2015
NO BIG CHANGES TO CURRENT FORECAST WITH WARMER AND DRIER WEATHER
EXPECTED ACROSS THE AREA THROUGH THE WEEKEND...ESPECIALLY ACROSS THE
SOUTHEAST PLAINS. ISOLATED HIGH BASED CONVECTION CAN NOT BE RULED
OUT OVER AND NEAR THE HIGHER TERRAIN LATE SATURDAY AFTERNOON WITH
ANY STORMS QUICKLY DIMINISHING WITH THE LOSS OF SOLAR INSOLATION. A
SLIGHT INCREASE IN AVAILABLE MOISTURE WITHIN THE WEST TO SOUTHWEST
FLOW ALOFT ON SUNDAY WILL ALLOW FOR SLIGHTLY BETTER COVERAGE OF
AFTERNOON AND EVENING STORMS OVER AND NEAR THE HIGHER TERRAIN SUNDAY
AFTERNOON AND EVENING...WITH STORMS REMAINING MAINLY HIGH BASED
PRODUCING MORE LIGHTNING AND GUSTY WINDS THAN RAINFALL. WARM TEMPS
ALOFT (14C TO 18C AT H7)...LESS EXPECTED CONVECTION AND WEAK
DOWNSLOPE FLOW...WILL KEEP TEMPERATURES AT AND ABOVE SEASONAL
AVERAGES IN THE 80S TO MID 90S ACROSS THE LOWER ELEVATIONS AND
MAINLY 60S AND 70S ACROSS THE HIGHER TERRAIN.
IT STILL LOOKS LIKE THE PATTERN WILL GRADUALLY BECOME COOLER AND
WETTER THROUGH THE MIDDLE OF NEXT WEEK...AS THE UPPER HIGH OVER THE
SOUTHERN ROCKIES DRIFTS SOUTH AND EAST ALLOWING FOR INCREASING
SUBTROPICAL MOISTURE INTO THE REGION. THIS...ALONG WITH A FEW
DISTURBANCES MOVING ACROSS THE NORTHERN ROCKIES AND HIGH PLAINS
SENDING WEAK FRONTS ACROSS THE EASTERN PLAINS...WILL ALLOW FOR
BETTER CHANCES OF WETTING RAINS AREAWIDE THROUGH THE MIDDLE OF NEXT
WEEK.
WARMER AND DRIER WEATHER MAY AGAIN BE IN THE OFFING FOR LATE NEXT
WEEK...AS DRIER AIR WITHIN DEVELOPING WESTERLY FLOW ALOFT LOOKS TO
WORK ITS WAY INTO THE REGION.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT)
ISSUED AT 1115 PM MDT FRI JUL 10 2015
VFR CONDITIONS ARE EXPECTED NEXT 24H AT ALL 3 TAF
SITES...KPUB...KALS AND KCOS. WINDS WILL BE LIGHT AND DIURNALLY
DRIVEN.
&&
.PUB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...28
LONG TERM...MW
AVIATION...HODANISH
AREA FORECAST DISCUSSION
NWS TAMPA BAY RUSKIN FL
859 PM EDT SUN JUL 12 2015
.UPDATE...
00Z WATER VAPOR AND H4 RAP ANALYSIS SHOWS A LARGE UPPER RIDGE
CONTINUES TO SPIN ACROSS MUCH OF THE DEEP SOUTH WITH AN AXIS
OVER THE SOUTHERN PLAINS. OUR FORECAST AREA RESIDES ON THE FAR
EASTERN PERIPHERY OF THIS RIDGE AND WE WILL SEE ITS INFLUENCE
CONTINUE TO DECREASE OVER THE NEXT 24 HOURS. THE DRY AIR ALOFT
THAT WAS WITH US LATE IN THE WORK WEEK IS NOW BEEN COMPLETELY
SCOURED OUT WITH WV IMAGERY SHOWING A RATHER MOIST MID/UPPER LEVEL
ENVIRONMENT.
IT WAS A COMPLEX DAY AROUND THE FORECAST AREA AS WE STARTED WITH A
LARGE COMPLEX OF STORMS OVER THE EASTERN GULF AND IMMEDIATE COAST
THAT THROUGH OUT A LARGE OUTFLOW BOUNDARY LATE IN THE MORNING.
THIS OUTFLOW PUSHED TO THE CENTER OF THE PENINSULA...AND MOST
AREAS IN ITS WAKE WERE SIMPLY NOT ABLE TO RECOVER THE LOW LEVEL
ENVIRONMENT ENOUGH TO SUPPORT LATE DAY STORMS. THE MOST ACTIVE
WEATHER WAS OVER OUR FAR NORTHERN NATURE COAST ZONES WHERE QUITE A
BIT OF RAINFALL FELL AS THE OUTFLOW INTERACTED WITH THE LARGE
SCALE FLOW FROM THE NORTH...AND DIFFLUENCE ALOFT.
FINALLY NOW SEEING THE LAST OF THE CONVECTION OVER THE NATURE
COAST FADING ON REGIONAL RADARS...AND MOST OF THE FORECAST AREA IS
GOING TO SEE A DRY REST OF THE OVERNIGHT.
SLOWLYDURING THE OVERNIGHT AND INTO MONDAY MORNING WE WILL SEE
OUR LOW LEVEL PATTERN BEGIN TO TRANSITION TO ONE SUPPORTIVE OF
LARGE SCALE SOUTHWESTERLY FLOW BETWEEN THE SUBTROPICAL RIDGE TO
OUR SOUTH...AND A WEAK FRONTAL BOUNDARY DROPPING INTO THE
SOUTHEASTERN CONUS. THIS FLOW WILL ONLY THEN STRENGTHEN AND BECOME
MORE DEFINED AS WE HEAD INTO THE MIDDLE OF THE WEEK. HOWEVER...FOR
MONDAY...IT WILL JUST BE STARTING. SOUTHWEST FLOW THIS TIME OF
YEAR IS FAVORABLE FOR A SCATTERING OF LOW TOPPED SHOWERS/STORMS TO
FORM LATE AT NIGHT AND APPROACH THE COAST DURING THE MORNING
HOURS. THIS MAY BEGIN MONDAY MORNING AND HAVE SOME LOW END CHANCE
POPS ALONG THE IMMEDIATE COAST AFTER SUNRISE. THIS ACTIVITY SHOULD
THEN BEGIN TO EXPAND IN SPATIAL EXTEND BY MIDDAY...AND THEN MAKE
PROGRESS INLAND THROUGH THE AFTERNOON. THE OVERALL INLAND
PROPAGATION OF THE CONVECTION WILL LIKELY BE SLOW ON MONDAY...BUT
WILL BE MUCH MORE DEFINED BY TUESDAY AND WEDNESDAY...WHEN AREAS
NEAR THE COAST COULD LIKELY SEE THEIR SHOWER CHANCES SIGNIFICANTLY
DECREASE AFTER 18Z...AS THE SEA BREEZE QUICKLY PUSHES INLAND.
&&
.AVIATION...
SHOWERS AND STORMS ARE COMING TO QUITE THE EARLY END THIS EVENING
COMPARED TO WHAT WE ARE USED TO THIS TIME OF YEAR. CIRRUS SHIELD
FROM EARLIER STORMS OVER THE I-4 CORRIDORS WILL DISSIPATE AND
SHIFT WESTWARD THIS EVENING WITH VFR CONDITIONS PREVAILING FOR ALL
TERMINALS THROUGH THE OVERNIGHT. TOWARD DAWN...SCT SHOWERS/STORMS
DEVELOPING OVER THE EASTERN GULF MAY APPROACH KTPA/KPIE/KSRQ...
WITH STORM CHANCES LINGERING THROUGH THE MORNING. CONVECTIVE
ACTIVITY THEN SLOWLY SHIFTS INLAND DURING THE AFTERNOON.
&&
.MARINE...
LIGHT AND VARIABLE FLOW OVER THE EASTERN GULF OVERNIGHT WITH
SCATTERED STORMS DEVELOPING AFTER MIDNIGHT INTO THROUGH THE
MORNING HOURS MONDAY. MONDAY IS THE TRANSITION DAY AS HIGH
PRESSURE SETTLES SOUTHWARD AND A FRONTAL SYSTEM DIPS INTO THE
SOUTHEASTERN STATES. THIS SETUP WILL BEGIN TO PROVIDE A LARGE
SCALE SOUTHWEST FLOW ACROSS THE FORECAST WATERS THAT WILL THEN
PREVAIL FOR THE MAJORITY OF THE UPCOMING WEEK. THE WINDS WILL BE
MOST STEADY APPROACHING 15 KNOTS AT TIMES STARTING TUESDAY TO THE
NORTH OF TARPON SPRINGS. SCATTERED SHOWERS AND STORMS ARE MOST
LIKELY IN SOUTHWEST FLOW DURING THE LATE NIGHT AND MORNING HOURS.
&&
.PRELIMINARY POINT TEMPS/POPS...
TPA 79 91 78 91 / 20 40 30 40
FMY 76 92 76 92 / 20 40 20 30
GIF 76 93 76 92 / 20 60 40 50
SRQ 77 91 78 91 / 20 40 30 40
BKV 75 93 74 91 / 30 50 20 40
SPG 80 91 79 90 / 20 40 30 40
&&
.TBW WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
GULF WATERS...NONE.
&&
$$
UPDATE/AVIATION/MARINE...14/MROCZKA
AREA FORECAST DISCUSSION
NWS MELBOURNE FL
342 AM EDT SAT JUL 11 2015
.DISCUSSION...
TODAY-TONIGHT...RIDGE ALOFT WILL SHIFT WESTWARD BUT STILL REMAIN
EXTENDED OVER THE SOUTHERN CONUS. THIS PATTERN HAS PRODUCED A
SWATH OF SUBSIDENCE/DRYING ALOFT ACROSS THE ATLANTIC AND ADJACENT
PORTIONS OF EAST CENTRAL FLORIDA. AT THE SURFACE...THE RIDGE AXIS
WILL DROP SOUTH OF THE CAPE WITH THE SLIGHT INCREASE IN SOUTH-
SOUTHWEST FLOW DELAYING THE SEA BREEZE ESPECIALLY ALONG THE
VOLUSIA COAST AN HOUR OR TWO BEHIND FRIDAY.
AIRMASS WILL INITIALLY BE VERY DRY WITH GPS PRECIPITABLE WATER
VALUES ABOUT 1.2 TO 1.3 INCHES...MAYBE A LITTLE GREATER INLAND
NORTH SECTIONS. THIS WILL ENSURE THAT RAIN CHANCES REMAIN BELOW
NORMAL. EVEN THOUGH THE HRRR IS GENERATING ISOLATED ACTIVITY ALONG
THE INLAND MOVING SEA BREEZE BOUNDARY...THINK THAT THE DRYNESS OF
THE AIR WILL PRECLUDE MENTIONABLE CHANCES EXCEPT WHERE THE
EAST/WEST BOUNDARY COLLISION OCCURS NEAR THE LAKE/ORANGE COUNTY
LINE LATE IN THE DAY.
LIMITED AND DELAYED AFTERNOON CONVECTION WILL ALLOW TEMPS TO REACH
THE LOWER 90S ALONG THE COAST. MID 90S WERE INDICATED INLAND
YESTERDAY AT THE MAIN OBSERVATION AND FAWN SITES. THEREFORE HAVE
STUCK WITH HIGHS IN THE MID 90S ACROSS THE INTERIOR AGAIN TODAY...
WITH NORTH COASTAL ZONE EVEN PUSHING TOWARDS 93-95 DEGREES.
SUN-TUE...EASTERN EXTENT OF RIDGE OVER THE SOUTHERN CONUS SHIFTS
WESTWARD AS TROUGH DEVELOPS DOWN OVER THE EASTERN U.S. INTO EARLY
NEXT WEEK. THIS SHIFTS SFC RIDGE AXIS SOUTH OF THE REGION. LOSS
OF SUPPRESSION FROM RIDGE ALOFT AND DEEPER MOISTURE MOVING INTO
THE AREA WILL LEAD TO INCREASING RAIN CHANCES THROUGH THE PERIOD.
RAIN CHANCES REMAIN OUT OF THE FORECAST ALONG THE COAST FROM THE
CAPE SOUTHWARD SUNDAY WHERE DRIER AIR LINGERS. HIGHEST POPS (UP TO
40-50 PERCENT) WILL EXIST FROM I-4 CORRIDOR WEST WHERE BOUNDARY
COLLISIONS WILL BE FAVORED LATER IN THE DAY AND EVENING. BEST RAIN
CHANCES THEN SHIFT ACROSS EAST CENTRAL FL INTO EARLY NEXT WEEK AS
LOW LEVEL FLOW BECOMES W/SW...FAVORING BOUNDARY COLLISIONS AND
GREATER STORM COVERAGE OVER THE REGION.
HIGHS WILL GENERALLY RANGE FROM THE LOW 90S ALONG THE COAST TO MID
90S INTERIOR ON SUNDAY...WITH LOW 90S OVER MUCH OF THE AREA MON/TUE
AS CONVECTIVE COVERAGE IS FORECAST TO BE GREATER.
WED-FRI...TROUGH OVER THE EASTERN U.S. WEAKENS INTO LATE WEEK WITH
SUBTROPICAL RIDGE AXIS SLOWLY LIFTING BACK NORTH...BUT STILL
REMAINING NEAR TO JUST SOUTH OF LAKE OKEECHOBEE. LOW LEVEL W/SW FLOW
MID WEEK GRADUALLY WEAKENS AND BECOMES MORE S/SW BY WEEKS END WHICH
SHOULD ALLOW THE SEA BREEZE TO HAVE MORE INLAND MOVEMENT...
ESPECIALLY SOUTH OF THE CAPE FRI. LINGERING DEEP MOISTURE WILL KEEP
SCATTERED SHOWERS AND STORMS IN THE FORECAST...PUSHING EASTWARD OVER
EAST CENTRAL FL WED/THU WITH BEST RAIN CHANCES THEN TRANSITIONING TO
THE INTERIOR FRI.
TEMPS WILL REMAIN NEAR SEASONAL NORMS WITH HIGHS IN THE LOW 90S AND
OVERNIGHT LOWS IN THE LOW TO MID 70S.
&&
.AVIATION...ANOTHER DAY WITH PRIMARILY VFR CONDITIONS. A SLIGHT
CHANCE FOR STORMS EXISTS LATE THIS AFTERNOON KSFB-KMCO-KISM WITH A
SLIGHTLY GREATER CHANCE AT KLEE BY EVENING. CHANCES ARE TOO LOW TO
INCLUDE IN THE TAFS JUST YET.
&&
.MARINE...
TODAY-TONIGHT...CONTINUED FAVORABLE CONDITIONS FOR SMALL CRAFT.
SURFACE RIDGE AXIS WILL MIGRATE SOUTH ACROSS THE WATERS TODAY.
THIS WILL PROVIDE FOR LIGHT WINDS EXCEPT FOR A 10 KNOT AFTERNOON
SEA BREEZE. THEN AS THE RIDGE SLIDES FARTHER SOUTH
TONIGHT...SOUTH/SOUTHWEST WINDS WILL INCREASE TO 10-15 KNOTS FROM
ABOUT THE CAPE NORTHWARD. DRIER THAN NORMAL AIR WAS PRODUCING
MOSTLY CLEAR SKIES EARLY THIS MORNING...SO DO NOT THINK THERE WILL
BE SIGNIFICANT CONVECTION OVER THE COASTAL WATERS.
SUN...RIDGE AXIS ACROSS THE AREA WILL ALLOW WINDS TO START OUT OF
THE S/SW IN THE MORNING AROUND 5-10 KTS BECOMING S/SE AND
INCREASING UP TO 10-15 KNOTS INTO THE AFT AS SEA BREEZE FORMS AND
MOVES INLAND. SEAS WILL RANGE FROM 1-3 FEET NEARSHORE UP TO 3-4 FEET
OFFSHORE.
MON-WED...RIDGE AXIS SHIFTS SOUTH OF CENTRAL FL WITH WINDS MORE
PREDOMINANTLY S/SW THROUGH THE PERIOD AND WIND SPEEDS GENERALLY
LESS THAN 15 KNOTS. SEAS WILL CONTINUE TO REMAIN AOB 4FT. MAIN
CONCERN FOR BOATERS WILL BE AN INCREASED THREAT FOR OFFSHORE MOVING
STORMS IN THE AFT AND EVE...PRODUCING GUSTY WINDS.
&&
.PRELIMINARY POINT TEMPS/POPS...
DAB 93 74 95 74 / 10 10 30 30
MCO 95 75 96 75 / 10 10 40 40
MLB 91 74 93 75 / 10 10 10 10
VRB 91 71 92 73 / 10 10 10 10
LEE 95 78 96 77 / 30 20 50 40
SFB 95 76 96 76 / 10 10 30 40
ORL 95 77 96 76 / 10 10 40 40
FPR 91 71 92 72 / 10 10 10 10
&&
.MLB WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
AM...NONE.
&&
$$
SHORT TERM...LASCODY
LONG TERM....WEITLICH
AREA FORECAST DISCUSSION
NWS LINCOLN IL
340 PM CDT SAT JUL 11 2015
.SHORT TERM...(TONIGHT)
ISSUED AT 325 PM CDT SAT JUL 11 2015
CONVECTIVE SYSTEM CONTINUES TO MARCH EAST WITH CELLS PROPAGATING
SOUTHEAST INTO A MUCH MORE UNSTABLE ATMOSPHERE ALONG THE SOUTHWEST
FLANK OF THE STORMS THIS AFTERNOON. EXPECT THE CLUSTER OF STORMS
TO PUSH EAST-SOUTHEAST AND BE BASICALLY TO OUR EAST AND SOUTH BY
02Z/9PM. THEN THE MAIN CHALLENGE WILL BE WITH ANY ADDITIONAL
DEVELOPMENT ALONG THE WARM FRONT AND ANY NEED FOR A FLASH FLOOD
WATCH FOR AT LEAST THE NORTHERN HALF OF THE FORECAST AREA. BASED
ON THE PAST FEW RUNS OF THE HRRR MODEL AND 18Z NAM...IT APPEARS
THE BULK OF THE RAINFALL WILL BE WITH THE AFTERNOON STORMS WITH
THE HI-RES/CONVECTIVE ALLOWING MODELS NOT SHOWING ANY SIGNIFICANT
DEVELOPMENT LATE THIS EVENING. HOWEVER...THE LATEST ECMWF AND TO
SOME EXTENT THE GFS DOES SHOW DEVELOPMENT LATER THIS EVENING INTO
THE OVERNIGHT HOURS ACROSS THE NORTH...IN AREAS THAT CAN NOT TAKE
ANY MORE RAINFALL (ROUGHLY NORTH OF A JACKSONVILLE TO SPRINGFIELD
TO CHAMPAIGN LINE). WILL GO AHEAD AND ISSUE A FLASH FLOOD WATCH
FOR TONIGHT INTO SUNDAY MORNING IN AREAS THAT HAVE THE LOWEST
FLASH FLOOD GUID VALUES. KNOX COUNTY HAS ALREADY RECEIVED FROM 1
TO 2 INCHES OF RAIN TODAY WITH AREAS FURTHER EAST NOW SEEING THE
RAINFALL...SO ANY ADDITIONAL RAINS ACROSS THE NORTH WILL POSE A
SIGNIFICANT FLASH FLOOD THREAT TONIGHT INTO SUNDAY MORNING.
&&
.LONG TERM...(SUNDAY THROUGH SATURDAY)
ISSUED AT 325 PM CDT SAT JUL 11 2015
SEVERAL STORM COMPLEXES/MCS AND POSSIBLE BOW ECHO LATE SUNDAY
NIGHT AND ESPECIALLY ON MONDAY/MONDAY EVENING AS MODELS DEPICT
AN EXTREMELY UNSTABLE ATMOSPHERE IN PLACE OVER CENTRAL ILLINOIS
MONDAY AFTERNOON AND EVENING. MIXED LAYER CAPES OF 3000-3500 ON
SUNDAY ACROSS THE WEST WITH MOST OF THE AREA SEEING 4000 J/KG
MIXED LAYER CAPES MONDAY AFTERNOON AND EVENING WITH BULK SHEAR
VALUES OF 35-45KTS. EXACT TIMING AND LOCATION THIS FAR OUT TOUGH
TO PIN DOWN BUT THE POTENTIAL IS THERE FOR A SWATH OF WIDESPREAD
DAMAGING WIND GUSTS AND ISOLATED TORNADOES MONDAY AFTERNOON AND
EVENING. THE THREAT ON SUNDAY APPEARS TO BE MORE WITH DAMAGING
WIND GUSTS FROM STORM CLUSTERS THE FORM TO OUR NORTHWEST AND SWEEP
SOUTHEAST INTO THE UNSTABLE AIR MASS. MOST OF THE MEDIUM RANGE
MODELS SUGGEST THE STRONGER SHORTWAVE TO TRACK ACROSST THE GREAT
LAKES LATE MONDAY NIGHT BRINGING A COOL FRONT SOUTHEAST INTO THE
AREA TEMPORARILY PUTTING AN END TO THE THREAT FOR WIDESPREAD
RAINFALL AND SEVERE STORMS TUESDAY AFTERNOON THRU WEDNESDAY...BEFORE
ANOTHER SHORTWAVE APPROACHES THE AREA LATE WED INTO THU ACCOMPANIED
BY SCATTERED THUNDERSTORM CHANCES INTO THE END OF THE WEEK.
ANOTHER CONCERN WILL BE WITH HEAT INDEX VALUES IN OUR WEST AND
SOUTHWEST TOMORROW AFTERNOON AND CWA WIDE ON MONDAY WHEN VALUES
WILL RANGE FROM 100-105.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON)
ISSUED AT 1227 PM CDT SAT JUL 11 2015
TIMING OF THUNDERSTORMS IS THE MOST SIGNIFICANT CHALLENGE FOR THIS
FORECAST. LINE OF CONVECTION CURRENTLY INTENSIFYING FROM NEAR
KUIN-KGBG MOVING EAST-SOUTHEAST AND WILL BE AFFECTING THE CENTRAL
ILLINOIS TAF SITES OVER THE NEXT FEW HOURS. FOCUSED SOME TEMPO
PERIODS FOR IFR CONDITIONS IN THE TAF`S FOR THE PASSAGE OF THE
LINE ITSELF. THERE IS LIKELY TO BE A PERIOD OF DRY CONDITIONS
BEHIND THE INITIAL CONVECTION BEFORE MORE FORMS TONIGHT.
HOWEVER...DO NOT HAVE MUCH CONFIDENCE IN NARROWING DOWN A SPECIFIC
TIME FRAME YET...SO WILL KEEP MENTION AS VCTS FOR NOW. HAVE
INDICATED SOME DRIER CONDITIONS LATE IN THE PERIOD THOUGH.
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
FLASH FLOOD WATCH THROUGH SUNDAY AFTERNOON FOR ILZ027>031-
036>038-040>043-047-048.
&&
$$
SHORT TERM...SMITH
LONG TERM...SMITH
AVIATION...SMITH
AREA FORECAST DISCUSSION
NWS LINCOLN IL
1227 PM CDT SAT JUL 11 2015
.UPDATE...
ISSUED AT 1000 AM CDT SAT JUL 11 2015
UPDATED THE FORECAST TO INCREASE THE RAIN CHANCES THIS MORNING AND
REFINE SOME OF THE TRENDS. BULK OF THE OVERNIGHT CONVECTION IS
CURRENTLY ACROSS THE SOUTHEAST HALF OF IOWA...ALTHOUGH IT IS ALSO
SHOWING AN EASTWARD PROGRESSION AND WILL BE AFFECTING THE NORTHERN
THIRD OF THE FORECAST AREA OVER THE NEXT FEW HOURS. ATTACHED WING
OF SHOWERS EXTENDS SOUTHEAST AND HAS BEEN WEAKENING...BUT WILL BE
AFFECTING EAST CENTRAL ILLINOIS THROUGH MIDDAY.
LATEST HRRR TRYING TO DEVELOP ADDITIONAL CONVECTION ACROSS WEST
CENTRAL ILLINOIS SHORTLY AFTER MIDDAY. SOME ENHANCEMENT IN THE
CUMULUS IS CURRENTLY STARTING TO APPEAR ACROSS NORTHERN MISSOURI
WHERE THERE IS SOME CLEARING...AND THIS IS LIKELY WHAT THE HRRR IS
PICKING UP ON. HAVE CONTINUED WITH THE HIGHER POP`S ACROSS THE
NORTHERN CWA WITH THE MCS...BUT MAY NEED TO BUMP UP THE SOUTHERN
AREAS ONCE THE CONVECTIVE TRENDS CAN BE ESTABLISHED.
&&
.SHORT TERM...(TODAY)
ISSUED AT 334 AM CDT SAT JUL 11 2015
WARM FRONTAL BOUNDARY LIFTING ACROSS CENTRAL IL AND SHORTWAVE
TROUGH PASSING THROUGH NORTHERN IL TODAY WILL BE THE FOCUS FOR
THUNDERSTORM ACTIVITY THROUGH THE EARLY PART OF THE DAY AS
SUBSTANTIAL MOISTURE ADVECTS INTO THE AREA CHARACTERIZED BY
PRECIPITABLE WATER AROUND 2 INCHES AND DEWPOINTS INTO THE 70S. A FEW
THUNDERSTORMS ALREADY DEVELOPING IN THE EARLY MORNING IN WEST
CENTRAL IL AS A RESULT OF ELEVATED INSTABILITY. THE SHORTWAVE
CURRENTLY APPEARS TIMED FOR LATE MORNING TO EARLY AFTERNOON...WITH A
POTENTIAL GAP IN THUNDERSTORM ACTIVITY FOR MID AFTERNOON AS ANOTHER
SHORTWAVE APPROACHES THE NORTHERN PORTION OF THE STATE FROM THE
WEST...BRINGING HIGHER CHANCES AGAIN FOR LATE AFTERNOON/EARLY
EVENING. THIS LATER ROUND OF STORMS COULD BE QUITE STRONG AS MLCAPE
VALUES AROUND 2000-2500 J/KG ARE FORECAST TO DEVELOP BY 00Z OVER
CENTRAL IL. 0-6 KM BULK SHEAR EXPECTED TO REMAIN ONLY AROUND 25 KTS.
SEVERE WEATHER THREATS WILL BE POTENTIAL FOR LOCALIZED DAMAGING WIND
GUSTS AND HAIL...FOR WHICH SPC HAS A MARGINAL (5%) RISK IN MUCH OF
CENTRAL/NORTHERN IL. POPS TODAY GENERALLY RANGING FROM CHANCE TO
LIKELY IN THE NORTHWESTERN PORTIONS OF THE CENTRAL IL FORECAST
AREA...RANGING DOWN TO SLIGHT CHANCE IN THE SOUTHEAST TO REFLECT
ABOVE REASONING. HIGH TEMPERATURES HAVE BEEN TRENDED DOWN A FEW
DEGREES TO THE LOW TO MID 80S DUE TO PREVALENT CLOUD COVER AND
SHOWERS/THUNDERSTORMS.
.LONG TERM...(TONIGHT THROUGH FRIDAY)
ISSUED AT 334 AM CDT SAT JUL 11 2015
MCS TO TRACK SE ACROSS CENTRAL/NORTHERN IL TONIGHT AND INCREASED
CHANCES OF SHOWERS AND THUNDERSTORMS. SPC HAS MARGINAL RISK OF
SEVERE STORMS NORTH OF I-70 FOR 5% RISK OF DAMAGING WINDS AND LARGE
HAIL. FRONTAL BOUNDARY TO SET UP JUST NE OF CENTRAL IL NEXT FEW DAYS
AND WILL HAVE DISTURBANCES TRACKING SE ALONG BOUNDARY BRINGING GOOD
CHANCES OF SHOWERS AND THUNDERSTORMS WITH NOCTURNAL LOW LEVEL JET
AND VERY UNSTABLE AIR MASS AIDING IN THUNDERSTORMS DEVELOPMENT.
HEAVY RAINS ALSO POSSIBLE WITH PRECIPITABLE WATER VALUES NEAR 2
INCHES. WILL WET GROUND HAVE TRIMMED HIGHS A FEW DEGREES NEXT FEW
DAYS BUT STILL HIGHS IN UPPER 80S TO AROUND 90F SUNDAY AND UPPER
80S/LOWER 90S MON. WITH DEWPOINTS CLIMBING INTO THE 70S AFTERNOON
HEAT INDICES TO RISE TO 95-100F SUNDAY AFTERNOON AND 99-104F
MONDAY AFTERNOON WHICH IS JUST SHY OF HEAT ADVISORY CRITERIA OF
105F.
SPC SHOWS A SLIGHT CHANCE OF SEVERE STORMS SUNDAY AFTERNOON INTO
SUNDAY NIGHT WITH ANOTHER MCS TRACKING SE FROM UPPER MS RIVER VALLEY
SUNDAY NIGHT. MEANWHILE ENHANCED RISK OF SEVERE STORMS MONDAY
AFTERNOON/EVENING FOR DAMAGING WINDS...LARGE HAIL AND POSSIBLE
TORNADOES. VERY UNSTABLE AIRMASS WITH CAPES OF 3-4K J/KG SUNDAY
AFTERNOON AND 4-6K J/KG MONDAY AFTERNOON.
00Z FORECAST MODELS CONTINUE TO SHOW AN ACTIVE WEATHER PATTERN OVER
IL THROUGH MIDDLE AND LATER PART OF NEXT WEEK WITH DAILY CHANCES OF
SHOWERS AND THUNDERSTORMS IN A WARM AND HUMID AIRMASS. SERIES OF
SHORT WAVES TO RIDE OVER TOP OF UPPER LEVEL RIDGE (CENTERED OVER THE
SOUTHERN PLAINS) THAT WILL TRACK NEAR IL WHICH IS IN WNW UPPER LEVEL
FLOW. A COLD FRONT TO TRACK SE THROUGH IL SOMETIME NEXT WEEKEND AND
CONTINUES CHANCES OF SHOWERS/THUNDERSTORMS. HIGHS IN THE 80S WITH
SOUTHEAST IL NEAR 90 AT TIMES WHILE LOWS CLOSE TO MUGGY DEWPOINTS IN
THE UPPER 60S TO MID 70S.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON)
ISSUED AT 1227 PM CDT SAT JUL 11 2015
TIMING OF THUNDERSTORMS IS THE MOST SIGNIFICANT CHALLENGE FOR THIS
FORECAST. LINE OF CONVECTION CURRENTLY INTENSIFYING FROM NEAR
KUIN-KGBG MOVING EAST-SOUTHEAST AND WILL BE AFFECTING THE CENTRAL
ILLINOIS TAF SITES OVER THE NEXT FEW HOURS. FOCUSED SOME TEMPO
PERIODS FOR IFR CONDITIONS IN THE TAF`S FOR THE PASSAGE OF THE
LINE ITSELF. THERE IS LIKELY TO BE A PERIOD OF DRY CONDITIONS
BEHIND THE INITIAL CONVECTION BEFORE MORE FORMS TONIGHT.
HOWEVER...DO NOT HAVE MUCH CONFIDENCE IN NARROWING DOWN A SPECIFIC
TIME FRAME YET...SO WILL KEEP MENTION AS VCTS FOR NOW. HAVE
INDICATED SOME DRIER CONDITIONS LATE IN THE PERIOD THOUGH.
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...GEELHART
SHORT TERM...ONTON
LONG TERM...07
AVIATION...GEELHART
AREA FORECAST DISCUSSION
NWS LINCOLN IL
1002 AM CDT SAT JUL 11 2015
.UPDATE...
ISSUED AT 1000 AM CDT SAT JUL 11 2015
UPDATED THE FORECAST TO INCREASE THE RAIN CHANCES THIS MORNING AND
REFINE SOME OF THE TRENDS. BULK OF THE OVERNIGHT CONVECTION IS
CURRENTLY ACROSS THE SOUTHEAST HALF OF IOWA...ALTHOUGH IT IS ALSO
SHOWING AN EASTWARD PROGRESSION AND WILL BE AFFECTING THE NORTHERN
THIRD OF THE FORECAST AREA OVER THE NEXT FEW HOURS. ATTACHED WING
OF SHOWERS EXTENDS SOUTHEAST AND HAS BEEN WEAKENING...BUT WILL BE
AFFECTING EAST CENTRAL ILLINOIS THROUGH MIDDAY.
LATEST HRRR TRYING TO DEVELOP ADDITIONAL CONVECTION ACROSS WEST
CENTRAL ILLINOIS SHORTLY AFTER MIDDAY. SOME ENHANCEMENT IN THE
CUMULUS IS CURRENTLY STARTING TO APPEAR ACROSS NORTHERN MISSOURI
WHERE THERE IS SOME CLEARING...AND THIS IS LIKELY WHAT THE HRRR IS
PICKING UP ON. HAVE CONTINUED WITH THE HIGHER POP`S ACROSS THE
NORTHERN CWA WITH THE MCS...BUT MAY NEED TO BUMP UP THE SOUTHERN
AREAS ONCE THE CONVECTIVE TRENDS CAN BE ESTABLISHED.
&&
.SHORT TERM...(TODAY)
ISSUED AT 334 AM CDT SAT JUL 11 2015
WARM FRONTAL BOUNDARY LIFTING ACROSS CENTRAL IL AND SHORTWAVE
TROUGH PASSING THROUGH NORTHERN IL TODAY WILL BE THE FOCUS FOR
THUNDERSTORM ACTIVITY THROUGH THE EARLY PART OF THE DAY AS
SUBSTANTIAL MOISTURE ADVECTS INTO THE AREA CHARACTERIZED BY
PRECIPITABLE WATER AROUND 2 INCHES AND DEWPOINTS INTO THE 70S. A FEW
THUNDERSTORMS ALREADY DEVELOPING IN THE EARLY MORNING IN WEST
CENTRAL IL AS A RESULT OF ELEVATED INSTABILITY. THE SHORTWAVE
CURRENTLY APPEARS TIMED FOR LATE MORNING TO EARLY AFTERNOON...WITH A
POTENTIAL GAP IN THUNDERSTORM ACTIVITY FOR MID AFTERNOON AS ANOTHER
SHORTWAVE APPROACHES THE NORTHERN PORTION OF THE STATE FROM THE
WEST...BRINGING HIGHER CHANCES AGAIN FOR LATE AFTERNOON/EARLY
EVENING. THIS LATER ROUND OF STORMS COULD BE QUITE STRONG AS MLCAPE
VALUES AROUND 2000-2500 J/KG ARE FORECAST TO DEVELOP BY 00Z OVER
CENTRAL IL. 0-6 KM BULK SHEAR EXPECTED TO REMAIN ONLY AROUND 25 KTS.
SEVERE WEATHER THREATS WILL BE POTENTIAL FOR LOCALIZED DAMAGING WIND
GUSTS AND HAIL...FOR WHICH SPC HAS A MARGINAL (5%) RISK IN MUCH OF
CENTRAL/NORTHERN IL. POPS TODAY GENERALLY RANGING FROM CHANCE TO
LIKELY IN THE NORTHWESTERN PORTIONS OF THE CENTRAL IL FORECAST
AREA...RANGING DOWN TO SLIGHT CHANCE IN THE SOUTHEAST TO REFLECT
ABOVE REASONING. HIGH TEMPERATURES HAVE BEEN TRENDED DOWN A FEW
DEGREES TO THE LOW TO MID 80S DUE TO PREVALENT CLOUD COVER AND
SHOWERS/THUNDERSTORMS.
.LONG TERM...(TONIGHT THROUGH FRIDAY)
ISSUED AT 334 AM CDT SAT JUL 11 2015
MCS TO TRACK SE ACROSS CENTRAL/NORTHERN IL TONIGHT AND INCREASED
CHANCES OF SHOWERS AND THUNDERSTORMS. SPC HAS MARGINAL RISK OF
SEVERE STORMS NORTH OF I-70 FOR 5% RISK OF DAMAGING WINDS AND LARGE
HAIL. FRONTAL BOUNDARY TO SET UP JUST NE OF CENTRAL IL NEXT FEW DAYS
AND WILL HAVE DISTURBANCES TRACKING SE ALONG BOUNDARY BRINGING GOOD
CHANCES OF SHOWERS AND THUNDERSTORMS WITH NOCTURNAL LOW LEVEL JET
AND VERY UNSTABLE AIR MASS AIDING IN THUNDERSTORMS DEVELOPMENT.
HEAVY RAINS ALSO POSSIBLE WITH PRECIPITABLE WATER VALUES NEAR 2
INCHES. WILL WET GROUND HAVE TRIMMED HIGHS A FEW DEGREES NEXT FEW
DAYS BUT STILL HIGHS IN UPPER 80S TO AROUND 90F SUNDAY AND UPPER
80S/LOWER 90S MON. WITH DEWPOINTS CLIMBING INTO THE 70S AFTERNOON
HEAT INDICES TO RISE TO 95-100F SUNDAY AFTERNOON AND 99-104F
MONDAY AFTERNOON WHICH IS JUST SHY OF HEAT ADVISORY CRITERIA OF
105F.
SPC SHOWS A SLIGHT CHANCE OF SEVERE STORMS SUNDAY AFTERNOON INTO
SUNDAY NIGHT WITH ANOTHER MCS TRACKING SE FROM UPPER MS RIVER VALLEY
SUNDAY NIGHT. MEANWHILE ENHANCED RISK OF SEVERE STORMS MONDAY
AFTERNOON/EVENING FOR DAMAGING WINDS...LARGE HAIL AND POSSIBLE
TORNADOES. VERY UNSTABLE AIRMASS WITH CAPES OF 3-4K J/KG SUNDAY
AFTERNOON AND 4-6K J/KG MONDAY AFTERNOON.
00Z FORECAST MODELS CONTINUE TO SHOW AN ACTIVE WEATHER PATTERN OVER
IL THROUGH MIDDLE AND LATER PART OF NEXT WEEK WITH DAILY CHANCES OF
SHOWERS AND THUNDERSTORMS IN A WARM AND HUMID AIRMASS. SERIES OF
SHORT WAVES TO RIDE OVER TOP OF UPPER LEVEL RIDGE (CENTERED OVER THE
SOUTHERN PLAINS) THAT WILL TRACK NEAR IL WHICH IS IN WNW UPPER LEVEL
FLOW. A COLD FRONT TO TRACK SE THROUGH IL SOMETIME NEXT WEEKEND AND
CONTINUES CHANCES OF SHOWERS/THUNDERSTORMS. HIGHS IN THE 80S WITH
SOUTHEAST IL NEAR 90 AT TIMES WHILE LOWS CLOSE TO MUGGY DEWPOINTS IN
THE UPPER 60S TO MID 70S.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SUNDAY MORNING)
ISSUED AT 702 AM CDT SAT JUL 11 2015
MAINLY VFR CONDITIONS ACROSS CENTRAL IL TERMINALS THIS MORNING
ALTHOUGH AREAS OF MVFR AND LOCALLY WORSE HAZE AND FOG TO CONTINUE
UNTIL 13Z-14Z. LOOSELY ORGANIZED BANDS OF SHOWERS/THUNDERSTORMS
LIFTING INTO CENTRAL IL THIS MORNING AS A WARM FRONT LIFTS THROUGH
THE REGION...AND HAVE INCORPORATED VCTS AND TEMPO TSRA TO REFLECT
TIMING OF THIS FEATURE FOR KPIA-KBMI-KSPI...USING HRRR MODEL
GUIDANCE WHICH LOOKS RELATIVELY ON TRACK WITH THE 11Z RUN. AFTER
THIS BAND...MODELS INDICATE MORE THUNDERSTORM ACTIVITY TRACKING IN
FROM THE WEST THROUGH NORTHERN SITES KPIA-KBMI SO HAVE NOT BEEN
ABLE TO TIME A CLEAR BREAK IN ACTIVITY THERE. AT OTHER
SITES...INCORPORATED VCTS AND LOW VFR CEILINGS 20Z AND LATER AS
MULTIPLE PERIODS OF THUNDERSTORMS POSSIBLE WITH LOW CONFIDENCE ON
TIMING AT THIS TIME. WINDS SE 3-6 KTS BECOMING SSE 6-10 KTS AFTER
14Z.
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...GEELHART
SHORT TERM...ONTON
LONG TERM...07
AVIATION...ONTON
AREA FORECAST DISCUSSION
NWS LINCOLN IL
702 AM CDT SAT JUL 11 2015
.SHORT TERM...(TODAY)
ISSUED AT 334 AM CDT SAT JUL 11 2015
WARM FRONTAL BOUNDARY LIFTING ACROSS CENTRAL IL AND SHORTWAVE
TROUGH PASSING THROUGH NORTHERN IL TODAY WILL BE THE FOCUS FOR
THUNDERSTORM ACTIVITY THROUGH THE EARLY PART OF THE DAY AS
SUBSTANTIAL MOISTURE ADVECTS INTO THE AREA CHARACTERIZED BY
PRECIPITABLE WATER AROUND 2 INCHES AND DEWPOINTS INTO THE 70S. A FEW
THUNDERSTORMS ALREADY DEVELOPING IN THE EARLY MORNING IN WEST
CENTRAL IL AS A RESULT OF ELEVATED INSTABILITY. THE SHORTWAVE
CURRENTLY APPEARS TIMED FOR LATE MORNING TO EARLY AFTERNOON...WITH A
POTENTIAL GAP IN THUNDERSTORM ACTIVITY FOR MID AFTERNOON AS ANOTHER
SHORTWAVE APPROACHES THE NORTHERN PORTION OF THE STATE FROM THE
WEST...BRINGING HIGHER CHANCES AGAIN FOR LATE AFTERNOON/EARLY
EVENING. THIS LATER ROUND OF STORMS COULD BE QUITE STRONG AS MLCAPE
VALUES AROUND 2000-2500 J/KG ARE FORECAST TO DEVELOP BY 00Z OVER
CENTRAL IL. 0-6 KM BULK SHEAR EXPECTED TO REMAIN ONLY AROUND 25 KTS.
SEVERE WEATHER THREATS WILL BE POTENTIAL FOR LOCALIZED DAMAGING WIND
GUSTS AND HAIL...FOR WHICH SPC HAS A MARGINAL (5%) RISK IN MUCH OF
CENTRAL/NORTHERN IL. POPS TODAY GENERALLY RANGING FROM CHANCE TO
LIKELY IN THE NORTHWESTERN PORTIONS OF THE CENTRAL IL FORECAST
AREA...RANGING DOWN TO SLIGHT CHANCE IN THE SOUTHEAST TO REFLECT
ABOVE REASONING. HIGH TEMPERATURES HAVE BEEN TRENDED DOWN A FEW
DEGREES TO THE LOW TO MID 80S DUE TO PREVALENT CLOUD COVER AND
SHOWERS/THUNDERSTORMS.
.LONG TERM...(TONIGHT THROUGH FRIDAY)
ISSUED AT 334 AM CDT SAT JUL 11 2015
MCS TO TRACK SE ACORSS CENTRAL/NORTHERN IL TONIGHT AND INCREASED
CHANCES OF SHOWERS AND THUNDERSTORMS. SPC HAS MARGINAL RISK OF
SEVERE STORMS NORTH OF I-70 FOR 5% RISK OF DAMAGING WINDS AND LARGE
HAIL. FRONTAL BOUNDARY TO SET UP JUST NE OF CENTRAL IL NEXT FEW DAYS
AND WILL HAVE DISTURBANCES TRACKING SE ALONG BOUNDARY BRINGING GOOD
CHANCES OF SHOWERS AND THUNDERSTORMS WITH NOCTURNAL LOW LEVEL JET
AND VERY UNSTABLE AIR MASS AIDING IN THUNDERSTORMS DEVELOPMENT.
HEAVY RAINS ALSO POSSIBLE WITH PRECIPITATABLE WATER VALUES NEAR 2
INCHES. WILL WET GROUND HAVE TRIMMED HIGHS A FEW DEGREES NEXT FEW
DAYS BUT STILL HIGHS IN UPPER 80S TO AROUND 90F SUNDAY AND UPPER
80S/LOWER 90S MON. WITH DEWPOINTS CLIMBING INTO THE 70S AFTERNOON
HEAT INDICES TO RISE TO 95-100F SUNDAY AFTERNOON AND 99-104F MONDAY
AFTERNOON WHICH IS JUST SHY OF HEAT ADVISORY CRITERIA OF 105F.
SPC SHOWS A SLIGHT CHANCE OF SEVERE STORMS SUNDAY AFTERNOON INTO
SUNDAY NIGHT WITH ANOTHER MCS TRACKING SE FROM UPPER MS RIVER VALLEY
SUNDAY NIGHT. MEANWHILE ENHANCED RISK OF SEVERE STORMS MONDAY
AFTERNOON/EVENING FOR DAMAGING WINDS...LARGE HAIL AND POSSIBLE
TORNADOES. VERY UNSTABLE AIRMASS WITH CAPES OF 3-4K J/KG SUNDAY
AFTERNOON AND 4-6K J/KG MONDAY AFTERNOON.
00Z FORECAST MODELS CONTINUE TO SHOW AN ACTIVE WEATHER PATTERN OVER
IL THROUGH MIDDLE AND LATER PART OF NEXT WEEK WITH DAILY CHANCES OF
SHOWERS AND THUNDERSTORMS IN A WARM AND HUMID AIRMASS. SERIES OF
SHORT WAVES TO RIDE OVER TOP OF UPPER LEVEL RIDGE (CENTERED OVER THE
SOUTHERN PLAINS) THAT WILL TRACK NEAR IL WHICH IS IN WNW UPPER LEVEL
FLOW. A COLD FRONT TO TRACK SE THROUGH IL SOMETIME NEXT WEEKEND AND
CONTINUES CHANCES OF SHOWERS/THUNDERSTORMS. HIGHS IN THE 80S WITH
SOUTHEAST IL NEAR 90 AT TIMES WHILE LOWS CLOSE TO MUGGY DEWPOINTS IN
THE UPPER 60S TO MID 70S.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SUNDAY MORNING)
ISSUED AT 702 AM CDT SAT JUL 11 2015
MAINLY VFR CONDITIONS ACROSS CENTRAL IL TERMINALS THIS MORNING
ALTHOUGH AREAS OF MVFR AND LOCALLY WORSE HAZE AND FOG TO CONTINUE
UNTIL 13Z-14Z. LOOSELY ORGANIZED BANDS OF SHOWERS/THUNDERSTORMS
LIFTING INTO CENTRAL IL THIS MORNING AS A WARM FRONT LIFTS THROUGH
THE REGION...AND HAVE INCORPORATED VCTS AND TEMPO TSRA TO REFLECT
TIMING OF THIS FEATURE FOR KPIA-KBMI-KSPI...USING HRRR MODEL
GUIDANCE WHICH LOOKS RELATIVELY ON TRACK WITH THE 11Z RUN. AFTER
THIS BAND...MODELS INDICATE MORE THUNDERSTORM ACTIVITY TRACKING IN
FROM THE WEST THROUGH NORTHERN SITES KPIA-KBMI SO HAVE NOT BEEN
ABLE TO TIME A CLEAR BREAK IN ACTIVITY THERE. AT OTHER
SITES...INCORPORATED VCTS AND LOW VFR CEILINGS 20Z AND LATER AS
MULTIPLE PERIODS OF THUNDERSTORMS POSSIBLE WITH LOW CONFIDENCE ON
TIMING AT THIS TIME. WINDS SE 3-6 KTS BECOMING SSE 6-10 KTS AFTER
14Z.
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...ONTON
LONG TERM...07
AVIATION...ONTON
AREA FORECAST DISCUSSION
NWS INDIANAPOLIS IN
235 PM EDT SAT JUL 11 2015
.UPDATE...
THE LONG TERM SECTION HAS BEEN UPDATED BELOW.
&&
.SYNOPSIS...
ISSUED AT 1012 AM EDT SAT JUL 11 2015
HIGH PRESSURE WILL SHIFT EAST OF THE REGION BY LATE DAY. AFTER THAT
LOW PRESSURE WILL DEVELOP OVER THE PLAINS AND SLOWLY HEAD
EAST...CAUSING VERY WARM HUMID AIR TO FLOW ACROSS OUR STATE.
EVENTUALLY THE LOW PRESSURE SHOULD BECOME ASSOCIATED WITH A COLD
FRONT...WHICH IS FORECAST TO CROSS THE HOOSIER STATE FROM TUESDAY
INTO WEDNESDAY. FOR THURSDAY INTO FRIDAY HIGH PRESSURE IS EXPECTED
TO TRAVERSE INDIANA FROM WEST TO EAST. THIS WILL CAUSE ANOTHER FLOW
OF WARM HUMID AIR BY THE WEEKEND.
&&
.NEAR TERM /REST OF TODAY/...
ISSUED AT 1012 AM EDT SAT JUL 11 2015
PATCHY DENSE FOG HAS NOW ALL BUT BURNED OFF ACROSS THE REGION...
WITH THE WELCOME SIGHT OF THE SUN AS WEAK HIGH PRESSURE DRIFTS
SLOWLY EAST. 14Z TEMPS GENERALLY RANGE FROM THE UPPER 60S TO LOWER
70S.
CLOUD DEBRIS ASSOCIATED WITH CONVECTION FROM CENTRAL ILLINOIS BACK
INTO SOUTHERN IOWA ALREADY EXPANDING INTO THE WESTERN FORECAST
AREA AND WILL DIMINISH SUNSHINE UNFORTUNATELY INTO THE AFTERNOON.
AIRMASS OVER THE REGION IS QUITE A BIT MORE STABLE THAN AREAS
FURTHER WEST...SO EXPECTATION IS THAT ONGOING STORMS OVER CENTRAL
INDIANA WILL WEAKEN AS THEY APPROACH THE WABASH VALLEY AROUND
MIDDAY. HRRR AND NMM-WRF BOTH HAVE A VERY GOOD HANDLE ON THIS
THINKING AND WAS UTILIZED FOR POPS INTO THE AFTERNOON. WILL
INTRODUCE SCHC POPS INTO THE NORTHERN HALF OF THE WABASH VALLEY BY
17Z WITH A SLOW EASTWARD EXPANSION THEREAFTER.
STILL THINK BETTER CHANCE FOR CONVECTION WILL HOLD OFF UNTIL LATE
AFTERNOON AT THE EARLIEST AND OVERNIGHT FOR MOST. INSTABILITY AND
PRECIP WATER VALUES WILL INCREASE GRADUALLY BY LATE AFTERNOON AS
THE REMNANT FRONTAL BOUNDARY APPROACHES...WITH HIGHEST VALUES
RESIDING IN THE WABASH VALLEY BY LATE DAY. SOME UNCERTAINTY EXISTS
IN HOW CONVECTION WILL REDEVELOP LATER ON OUT WEST WITH SOME HINTS
AT INITIATION ACROSS NORTHEAST MISSOURI AND CENTRAL ILLINOIS ALONG
THE INSTABILITY GRADIENT AND AT THE NOSE OF THE LOW LEVEL
JET...WITH ADDITIONAL DEVELOPMENT DURING THE EVENING OVER NORTHERN
ILLINOIS AIDED BY THE JET. STILL ANTICIPATE THIS ACTIVITY TO RIDE
THE INSTABILITY GRADIENT AND REMNANT BOUNDARY INTO THE AREA
TONIGHT WITH STRONG STORMS AND HEAVY RAIN POTENTIAL.
LOWERED HIGH TEMPS SLIGHTLY WITH EXPECTED CLOUD COVERAGE LATER ON
TODAY. ZONE AND GRID UPDATES OUT.
&&
.SHORT TERM /SUNDAY THROUGH TUESDAY NIGHT/...
ISSUED AT 250 AM EDT SAT JUL 11 2015
AS FOR SOME TIME...PRECIPITATION IS THE MAIN ISSUE.
ALL MODELS HAVE THE CWA UNDER POSITIVE ADVECTION OF WET BULB
POTENTIAL TEMPERATURE TONIGHT. THIS IS LIABLE TO FIRE A CONVECTIVE
SYSTEM. THE MODELS REFLECT THIS FAIRLY WELL IN THEIR WET POPS.
THE PRECIPITABLE WATER DOESNT LOOK QUITE ENOUGH FOR WIDESPREAD HEAVY
RAIN AND A FLOOD WATCH TONIGHT. IT IS ENOUGH TO MENTION LOCALLY
HEAVY RAIN.
SUNDAY INTO TUESDAY NIGHT THINGS GET COMPLICATED. THERE IS A LOT
OF DISAGREEMENT BETWEEN ON THE MODELS ON THE LOCATION OF SUBTLE
FEATURES THAT WILL DRIVE CONVECTION. WITH THAT
UNCERTAINTY...CHANCE POPS SEEM BEST MOST OF THE TIME.
GIVEN THE UNCERTAINTY ABOUT POPS THERE IS ALSO UNCERTAINTY ABOUT
TEMPERATURES. ON AVERAGE...A CONSENSUS FORECAST IS THE WAY TO GO IN
SUCH SITUATIONS...SO AN CONSENSUS OF THE MAV AND MET WILL BE USED.
AN EXCEPTION WILL BE MADE TUESDAY. SLIGHT CUTS WILL BE MADE.
ITS HARD TO SEE MANY PLACES HITTING 90 GIVEN THE GROUND SHOULD
BE QUITE WET.
AN INTERESTING FEATURE ON MONDAY IS THE FORECAST CAPES NOT TOO FAR
TO OUR WEST. THEY ARE LITERALLY THE HIGHEST I HAVE EVER SEEN. MONDAY
MAY BE AN EXCITING DAY.
&&
.LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/...
ISSUED AT 235 PM EDT SAT JUL 11 2015
STOP ME IF YOUVE HEARD THIS ONE BEFORE...STORMS WILL BE A THREAT
EACH PERIOD THROUGHOUT THE LONG TERM. BROAD RIDGE OF HIGH PRESSURE
ACROSS THE SOUTH CENTRAL US LOOKS TO KEEP STORM TRACK NORTH AND
ALLOW FOR THE POSSIBILITY OF SEVERAL RIDGE RIDING STORM SYSTEMS TO
IMPACT THE AREA THROUGH THE WEEK. THAT IS NOT TO SAY THAT THERE WILL
NOT BE SIGNIFICANT DRY PERIODS...BUT STORM CHANCES WILL BE REQUIRED
EACH PERIOD THROUGH THE LONG TERM PORTION OF THE FORECAST.
TEMPERATURES NEAR CLIMATOLOGICAL NORMALS CAN BE EXPECTED WITH THE
AREA ON THE PERIPHERY OF THE RIDGE. CONVECTION WILL HAVE THE
POTENTIAL TO SIGNIFICANTLY IMPACT TEMPERATURES BUT WITH VERY HIGH
UNCERTAINTY AS TO TIMING...CAN SEE LITTLE REASON TO DEVIATE FROM
CONSENSUS NUMBERS AT THIS POINT.
&&
.AVIATION /DISCUSSION FOR THE 11/18Z TAFS/...
ISSUED AT 112 PM EDT SAT JUL 11 2015
VFR THROUGH THE PERIOD OUTSIDE OF ANY POTENTIAL THUNDERSTORMS.
EXPECT A QUIET AFTERNOON TO CONTINUE ACROSS CENTRAL
INDIANA...ALTHOUGH SHORT TERM GUIDANCE NOW INDICATES THAT CONVECTIVE
ACTIVITY OVER WESTERN ILLINOIS MAY GET INTO THE SITES EARLIER THAN
PREVIOUSLY FORECAST. WILL MOVE SHOWER/VCTS MENTION UP A FEW HOURS.
HOWEVER...ONCE IT IS IN WILL KEEP IT IN FOR THE DURATION.
RESTRICTIONS WILL LIKELY OCCUR AT TIMES WHEN SHOWERS/THUNDERSTORMS
IMPACT THE SITES BUT THESE IMPACTS ARE FAR TOO UNCERTAIN FOR MENTION
AT THIS POINT.
WINDS WILL BE 10KT OR LESS THROUGHOUT THE PERIOD.
&&
.IND WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
SYNOPSIS...JK/RYAN
NEAR TERM...RYAN
SHORT TERM...JK
LONG TERM...NIELD
AVIATION...NIELD
VISIT US AT HTTP://WWW.WEATHER.GOV/IND
FOLLOW US ON FACEBOOK...TWITTER AND YOUTUBE AT:
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AREA FORECAST DISCUSSION
NWS INDIANAPOLIS IN
112 PM EDT SAT JUL 11 2015
.UPDATE...
THE AVIATION SECTION HAS BEEN UPDATED BELOW.
&&
.SYNOPSIS...
ISSUED AT 1012 AM EDT SAT JUL 11 2015
HIGH PRESSURE WILL SHIFT EAST OF THE REGION BY LATE DAY. AFTER THAT
LOW PRESSURE WILL DEVELOP OVER THE PLAINS AND SLOWLY HEAD
EAST...CAUSING VERY WARM HUMID AIR TO FLOW ACROSS OUR STATE.
EVENTUALLY THE LOW PRESSURE SHOULD BECOME ASSOCIATED WITH A COLD
FRONT...WHICH IS FORECAST TO CROSS THE HOOSIER STATE FROM TUESDAY
INTO WEDNESDAY. FOR THURSDAY INTO FRIDAY HIGH PRESSURE IS EXPECTED
TO TRAVERSE INDIANA FROM WEST TO EAST. THIS WILL CAUSE ANOTHER FLOW
OF WARM HUMID AIR BY THE WEEKEND.
&&
.NEAR TERM /REST OF TODAY/...
ISSUED AT 1012 AM EDT SAT JUL 11 2015
PATCHY DENSE FOG HAS NOW ALL BUT BURNED OFF ACROSS THE REGION...
WITH THE WELCOME SIGHT OF THE SUN AS WEAK HIGH PRESSURE DRIFTS
SLOWLY EAST. 14Z TEMPS GENERALLY RANGE FROM THE UPPER 60S TO LOWER
70S.
CLOUD DEBRIS ASSOCIATED WITH CONVECTION FROM CENTRAL ILLINOIS BACK
INTO SOUTHERN IOWA ALREADY EXPANDING INTO THE WESTERN FORECAST
AREA AND WILL DIMINISH SUNSHINE UNFORTUNATELY INTO THE AFTERNOON.
AIRMASS OVER THE REGION IS QUITE A BIT MORE STABLE THAN AREAS
FURTHER WEST...SO EXPECTATION IS THAT ONGOING STORMS OVER CENTRAL
INDIANA WILL WEAKEN AS THEY APPROACH THE WABASH VALLEY AROUND
MIDDAY. HRRR AND NMM-WRF BOTH HAVE A VERY GOOD HANDLE ON THIS
THINKING AND WAS UTILIZED FOR POPS INTO THE AFTERNOON. WILL
INTRODUCE SCHC POPS INTO THE NORTHERN HALF OF THE WABASH VALLEY BY
17Z WITH A SLOW EASTWARD EXPANSION THEREAFTER.
STILL THINK BETTER CHANCE FOR CONVECTION WILL HOLD OFF UNTIL LATE
AFTERNOON AT THE EARLIEST AND OVERNIGHT FOR MOST. INSTABILITY AND
PRECIP WATER VALUES WILL INCREASE GRADUALLY BY LATE AFTERNOON AS
THE REMNANT FRONTAL BOUNDARY APPROACHES...WITH HIGHEST VALUES
RESIDING IN THE WABASH VALLEY BY LATE DAY. SOME UNCERTAINTY EXISTS
IN HOW CONVECTION WILL REDEVELOP LATER ON OUT WEST WITH SOME HINTS
AT INITIATION ACROSS NORTHEAST MISSOURI AND CENTRAL ILLINOIS ALONG
THE INSTABILITY GRADIENT AND AT THE NOSE OF THE LOW LEVEL
JET...WITH ADDITIONAL DEVELOPMENT DURING THE EVENING OVER NORTHERN
ILLINOIS AIDED BY THE JET. STILL ANTICIPATE THIS ACTIVITY TO RIDE
THE INSTABILITY GRADIENT AND REMNANT BOUNDARY INTO THE AREA
TONIGHT WITH STRONG STORMS AND HEAVY RAIN POTENTIAL.
LOWERED HIGH TEMPS SLIGHTLY WITH EXPECTED CLOUD COVERAGE LATER ON
TODAY. ZONE AND GRID UPDATES OUT.
&&
.SHORT TERM /SUNDAY THROUGH TUESDAY NIGHT/...
ISSUED AT 250 AM EDT SAT JUL 11 2015
AS FOR SOME TIME...PRECIPITATION IS THE MAIN ISSUE.
ALL MODELS HAVE THE CWA UNDER POSITIVE ADVECTION OF WET BULB
POTENTIAL TEMPERATURE TONIGHT. THIS IS LIABLE TO FIRE A CONVECTIVE
SYSTEM. THE MODELS REFLECT THIS FAIRLY WELL IN THEIR WET POPS.
THE PRECIPITABLE WATER DOESNT LOOK QUITE ENOUGH FOR WIDESPREAD HEAVY
RAIN AND A FLOOD WATCH TONIGHT. IT IS ENOUGH TO MENTION LOCALLY
HEAVY RAIN.
SUNDAY INTO TUESDAY NIGHT THINGS GET COMPLICATED. THERE IS A LOT
OF DISAGREEMENT BETWEEN ON THE MODELS ON THE LOCATION OF SUBTLE
FEATURES THAT WILL DRIVE CONVECTION. WITH THAT
UNCERTAINTY...CHANCE POPS SEEM BEST MOST OF THE TIME.
GIVEN THE UNCERTAINTY ABOUT POPS THERE IS ALSO UNCERTAINTY ABOUT
TEMPERATURES. ON AVERAGE...A CONSENSUS FORECAST IS THE WAY TO GO IN
SUCH SITUATIONS...SO AN CONSENSUS OF THE MAV AND MET WILL BE USED.
AN EXCEPTION WILL BE MADE TUESDAY. SLIGHT CUTS WILL BE MADE.
ITS HARD TO SEE MANY PLACES HITTING 90 GIVEN THE GROUND SHOULD
BE QUITE WET.
AN INTERESTING FEATURE ON MONDAY IS THE FORECAST CAPES NOT TOO FAR
TO OUR WEST. THEY ARE LITERALLY THE HIGHEST I HAVE EVER SEEN. MONDAY
MAY BE AN EXCITING DAY.
&&
.LONG TERM /TUESDAY THROUGH FRIDAY/...
ISSUED AT 227 AM EDT SAT JUL 11 2015
AN ACTIVE PATTERN WILL CONTINUE THROUGH THE LONG TERM AS AN UPPER
RIDGE COVERING THE CENTRAL U.S. BROADENS AND FLATTENS OUT. THIS WILL
ALLOW A SERIES OF WEAK UPPER WAVES TO MOVE THROUGH MAIN FLOW. MODELS
ARE IN GOOD AGREEMENT ON THIS OVERALL PATTERN BUT DIFFER ON THE
TIMING OF THESE PERTURBATIONS...AND THUS WILL CONTINUE WITH
INITIALIZATION RESPONSE OF INCLUDING CHANCES FOR THUNDERSTORMS
THROUGHOUT THE LONG TERM. THAT SAID STILL EXPECT DRY TIMES DURING
THE LONG TERM...JUST UNABLE TO PIN THEM DOWN AT THIS POINT.
INITIALIZATION KEEPS HIGH TEMPERATURES NEAR NORMAL IN THE MIDDLE 80S
AND SAW NO REASON TO DEVIATE FROM THIS...ALTHOUGH NOT HIGH
CONFIDENCE IN THESE GIVEN THE POTENTIAL FOR RAINFALL TO DECREASE
THEM WHEN IT DEVELOPS.
&&
.AVIATION /DISCUSSION FOR THE 11/18Z TAFS/...
ISSUED AT 112 PM EDT SAT JUL 11 2015
VFR THROUGH THE PERIOD OUTSIDE OF ANY POTENTIAL THUNDERSTORMS.
EXPECT A QUIET AFTERNOON TO CONTINUE ACROSS CENTRAL
INDIANA...ALTHOUGH SHORT TERM GUIDANCE NOW INDICATES THAT CONVECTIVE
ACTIVITY OVER WESTERN ILLINOIS MAY GET INTO THE SITES EARLIER THAN
PREVIOUSLY FORECAST. WILL MOVE SHOWER/VCTS MENTION UP A FEW HOURS.
HOWEVER...ONCE IT IS IN WILL KEEP IT IN FOR THE DURATION.
RESTRICTIONS WILL LIKELY OCCUR AT TIMES WHEN SHOWERS/THUNDERSTORMS
IMPACT THE SITES BUT THESE IMPACTS ARE FAR TOO UNCERTAIN FOR MENTION
AT THIS POINT.
WINDS WILL BE 10KT OR LESS THROUGHOUT THE PERIOD.
&&
.IND WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
SYNOPSIS...JK/RYAN
NEAR TERM...RYAN
SHORT TERM...JK
LONG TERM...CP
AVIATION...NIELD
VISIT US AT HTTP://WWW.WEATHER.GOV/IND
FOLLOW US ON FACEBOOK...TWITTER AND YOUTUBE AT:
WWW.FACEBOOK.COM/NWSINDIANAPOLIS
WWW.TWITTER.COM/NWSINDIANAPOLIS
WWW.YOUTUBE.COM/NWSINDIANAPOLIS
AREA FORECAST DISCUSSION
NWS INDIANAPOLIS IN
1012 AM EDT SAT JUL 11 2015
.UPDATE...
THE NEAR TERM SECTION HAS BEEN UPDATED BELOW.
&&
.SYNOPSIS...
ISSUED AT 1012 AM EDT SAT JUL 11 2015
HIGH PRESSURE WILL SHIFT EAST OF THE REGION BY LATE DAY. AFTER THAT
LOW PRESSURE WILL DEVELOP OVER THE PLAINS AND SLOWLY HEAD
EAST...CAUSING VERY WARM HUMID AIR TO FLOW ACROSS OUR STATE.
EVENTUALLY THE LOW PRESSURE SHOULD BECOME ASSOCIATED WITH A COLD
FRONT...WHICH IS FORECAST TO CROSS THE HOOSIER STATE FROM TUESDAY
INTO WEDNESDAY. FOR THURSDAY INTO FRIDAY HIGH PRESSURE IS EXPECTED
TO TRAVERSE INDIANA FROM WEST TO EAST. THIS WILL CAUSE ANOTHER FLOW
OF WARM HUMID AIR BY THE WEEKEND.
&&
.NEAR TERM /REST OF TODAY/...
ISSUED AT 1012 AM EDT SAT JUL 11 2015
PATCHY DENSE FOG HAS NOW ALL BUT BURNED OFF ACROSS THE REGION...
WITH THE WELCOME SIGHT OF THE SUN AS WEAK HIGH PRESSURE DRIFTS
SLOWLY EAST. 14Z TEMPS GENERALLY RANGE FROM THE UPPER 60S TO LOWER
70S.
CLOUD DEBRIS ASSOCIATED WITH CONVECTION FROM CENTRAL ILLINOIS BACK
INTO SOUTHERN IOWA ALREADY EXPANDING INTO THE WESTERN FORECAST
AREA AND WILL DIMINISH SUNSHINE UNFORTUNATELY INTO THE AFTERNOON.
AIRMASS OVER THE REGION IS QUITE A BIT MORE STABLE THAN AREAS
FURTHER WEST...SO EXPECTATION IS THAT ONGOING STORMS OVER CENTRAL
INDIANA WILL WEAKEN AS THEY APPROACH THE WABASH VALLEY AROUND
MIDDAY. HRRR AND NMM-WRF BOTH HAVE A VERY GOOD HANDLE ON THIS
THINKING AND WAS UTILIZED FOR POPS INTO THE AFTERNOON. WILL
INTRODUCE SCHC POPS INTO THE NORTHERN HALF OF THE WABASH VALLEY BY
17Z WITH A SLOW EASTWARD EXPANSION THEREAFTER.
STILL THINK BETTER CHANCE FOR CONVECTION WILL HOLD OFF UNTIL LATE
AFTERNOON AT THE EARLIEST AND OVERNIGHT FOR MOST. INSTABILITY AND
PRECIP WATER VALUES WILL INCREASE GRADUALLY BY LATE AFTERNOON AS
THE REMNANT FRONTAL BOUNDARY APPROACHES...WITH HIGHEST VALUES
RESIDING IN THE WABASH VALLEY BY LATE DAY. SOME UNCERTAINTY EXISTS
IN HOW CONVECTION WILL REDEVELOP LATER ON OUT WEST WITH SOME HINTS
AT INITIATION ACROSS NORTHEAST MISSOURI AND CENTRAL ILLINOIS ALONG
THE INSTABILITY GRADIENT AND AT THE NOSE OF THE LOW LEVEL
JET...WITH ADDITIONAL DEVELOPMENT DURING THE EVENING OVER NORTHERN
ILLINOIS AIDED BY THE JET. STILL ANTICIPATE THIS ACTIVITY TO RIDE
THE INSTABILITY GRADIENT AND REMNANT BOUNDARY INTO THE AREA
TONIGHT WITH STRONG STORMS AND HEAVY RAIN POTENTIAL.
LOWERED HIGH TEMPS SLIGHTLY WITH EXPECTED CLOUD COVERAGE LATER ON
TODAY. ZONE AND GRID UPDATES OUT.
&&
.SHORT TERM /SUNDAY THROUGH TUESDAY NIGHT/...
ISSUED AT 250 AM EDT SAT JUL 11 2015
AS FOR SOME TIME...PRECIPITATION IS THE MAIN ISSUE.
ALL MODELS HAVE THE CWA UNDER POSITIVE ADVECTION OF WET BULB
POTENTIAL TEMPERATURE TONIGHT. THIS IS LIABLE TO FIRE A CONVECTIVE
SYSTEM. THE MODELS REFLECT THIS FAIRLY WELL IN THEIR WET POPS.
THE PRECIPITABLE WATER DOESNT LOOK QUITE ENOUGH FOR WIDESPREAD HEAVY
RAIN AND A FLOOD WATCH TONIGHT. IT IS ENOUGH TO MENTION LOCALLY
HEAVY RAIN.
SUNDAY INTO TUESDAY NIGHT THINGS GET COMPLICATED. THERE IS A LOT
OF DISAGREEMENT BETWEEN ON THE MODELS ON THE LOCATION OF SUBTLE
FEATURES THAT WILL DRIVE CONVECTION. WITH THAT
UNCERTAINTY...CHANCE POPS SEEM BEST MOST OF THE TIME.
GIVEN THE UNCERTAINTY ABOUT POPS THERE IS ALSO UNCERTAINTY ABOUT
TEMPERATURES. ON AVERAGE...A CONSENSUS FORECAST IS THE WAY TO GO IN
SUCH SITUATIONS...SO AN CONSENSUS OF THE MAV AND MET WILL BE USED.
AN EXCEPTION WILL BE MADE TUESDAY. SLIGHT CUTS WILL BE MADE.
ITS HARD TO SEE MANY PLACES HITTING 90 GIVEN THE GROUND SHOULD
BE QUITE WET.
AN INTERESTING FEATURE ON MONDAY IS THE FORECAST CAPES NOT TOO FAR
TO OUR WEST. THEY ARE LITERALLY THE HIGHEST I HAVE EVER SEEN. MONDAY
MAY BE AN EXCITING DAY.
&&
.LONG TERM /TUESDAY THROUGH FRIDAY/...
ISSUED AT 227 AM EDT SAT JUL 11 2015
AN ACTIVE PATTERN WILL CONTINUE THROUGH THE LONG TERM AS AN UPPER
RIDGE COVERING THE CENTRAL U.S. BROADENS AND FLATTENS OUT. THIS WILL
ALLOW A SERIES OF WEAK UPPER WAVES TO MOVE THROUGH MAIN FLOW. MODELS
ARE IN GOOD AGREEMENT ON THIS OVERALL PATTERN BUT DIFFER ON THE
TIMING OF THESE PERTURBATIONS...AND THUS WILL CONTINUE WITH
INITIALIZATION RESPONSE OF INCLUDING CHANCES FOR THUNDERSTORMS
THROUGHOUT THE LONG TERM. THAT SAID STILL EXPECT DRY TIMES DURING
THE LONG TERM...JUST UNABLE TO PIN THEM DOWN AT THIS POINT.
INITIALIZATION KEEPS HIGH TEMPERATURES NEAR NORMAL IN THE MIDDLE 80S
AND SAW NO REASON TO DEVIATE FROM THIS...ALTHOUGH NOT HIGH
CONFIDENCE IN THESE GIVEN THE POTENTIAL FOR RAINFALL TO DECREASE
THEM WHEN IT DEVELOPS.
&&
.AVIATION /DISCUSSION FOR 111200Z TAF ISSUANCE/...
ISSUED AT 647 AM EDT SAT JUL 11 2015
FOG AND LOW/OBSCURED CEILINGS SHOULD BURN OFF WITHIN AN HOUR OR TWO
OF ISSUANCE AND VFR CONDITIONS WILL ENSUE FOR THE DAY. CHANCES FOR
THUNDERSTORMS WILL ARRIVE THIS AFTERNOON AND EVENING...BUT LATEST
GUIDANCE INDICATES THE BEST POTENTIAL WON/T BE ARRIVING UNTIL LATE.
THUS PUSHED BACK ONSET OF VCTS BACK TO AROUND 3Z OR SO IN THE WEST
AT KHUF AND OVERSPREAD THE OTHER SITES FROM THERE. TIME HEIGHT
SECTIONS INDICATE GOOD POTENTIAL FOR RISING MOTION TO CONTINUE INTO
SUNDAY MORNING SO ONCE VCTS STARTS WILL KEEP IT GOING FOR THE
DURATION.
&&
.IND WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
SYNOPSIS...JK/RYAN
NEAR TERM...RYAN
SHORT TERM...JK
LONG TERM....CP
AVIATION...CP
VISIT US AT HTTP://WWW.WEATHER.GOV/IND
FOLLOW US ON FACEBOOK...TWITTER AND YOUTUBE AT:
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AREA FORECAST DISCUSSION
NWS DES MOINES IA
635 PM CDT SUN JUL 12 2015
.SHORT TERM /TONIGHT/...
ISSUED AT 337 PM CDT SUN JUL 12 2015
MAIN ISSUE OVERNIGHT IS THE THREAT OF THUNDERSTORMS...SOME OF
WHICH COULD BE SEVERE.
FRONTAL BOUNDARY ALIGNS ROUGHLY WITH PERSISTENT STRATUS
FIELD...AND DEWPOINTS HAVE POOLED JUST UPSTREAM FROM THIS
BOUNDARY. CLOSEST ACTIVE CONVECTION IS STILL IN NORTHERN
MINNESOTA...BUT SHORT WAVE TROF IS APPROACHING SOUTH DAKOTA
MINNESOTA LINE AT THIS TIME AND SHOULD ENHANCE CONVECTIVE
COVERAGE. MOST CONVECTIVE ALLOWING MODELS KEEP MAIN MCS EAST OF
THIS FORECAST AREA BUT THE HRRR HAS BEEN INDICATING A POSSIBILITY
OF ISOLATED STORMS ALONG THE SOUTHWESTERN END OF THE ADVANCING
CONVECTION. IF THESE FORM IT WILL QUICKLY GO SEVERE WITH LARGE
HAIL AND WIND THE PRIMARY THREAT. MAIN MCS SHOULD MOVE PAST THE
AREA BY 12 UTC AND FRONT DOESN`T REALLY MOVE MUCH BY THEN.
.LONG TERM /MONDAY THROUGH SUNDAY/...
ISSUED AT 337 PM CDT SUN JUL 12 2015
HOT AND HUMID CONDITIONS CONTINUE ON MONDAY OVER THE SOUTHERN
HALF OF THE FORECAST AREA AND RAIN CHANCES WEDNESDAY NIGHT INTO
THURSDAY WERE THE MAIN ISSUES DURING THE EXTENDED PERIOD. LEANED
TOWARD A NAM12/ECMWF BLEND FOR TEMPS MONDAY INTO TUESDAY AND
CLOSER TO THE ECMWF/GFS THROUGH NEXT WEEKEND.
MONDAY AND TUESDAY...TWEAKED MAX TEMPS UP SLIGHTLY ALONG WITH DEW
POINTS OVER CENTRAL TO SOUTHEAST PORTIONS OF THE FORECAST AREA
AS THE COLD FRONT LOOKS TO BE A BIT SLOWER IN PROGRESSING ACROSS
THE STATE UNTIL LATER IN THE AFTERNOON. NOT A SIGNIFICANT AMOUNT
OF FORCING WITH THE FRONT...BUT ENOUGH THERE TO KEEP SLIGHT POPS
GOING IN THE AFTERNOON ACROSS THE EAST. SURFACE HIGH PRESSURE AND
UPPER LEVEL RIDGE HOLD IN PLACE ON TUESDAY WILL PROVIDE A MUCH
LESS HUMID AIR MASS OVER THE STATE. SOME MIXING LOOKS TO PUSH
TEMPS BACK INTO THE LOWER 90S OVER THE CENTRAL TO SOUTH
TUESDAY...BUT WITH LESS HUMIDITY NOT CONCERNED WITH EXTREME HEAT
INDEX VALUES.
WEDNESDAY INTO THURSDAY...LARGE UPPER LEVEL RIDGE PERSISTS ACROSS
THE CENTRAL U.S. THROUGH THE END OF THE WEEK. THE STRONGEST
SHORTWAVE AND BEST CONFIDENCE IN ANY PRECIPITATION DURING THE
EXTENDED IS WEDNESDAY NIGHT INTO THURSDAY. ECMWF AND GFS ARE IN
SOMEWHAT GOOD AGREEMENT WRT TO PRECIP CHANCES DURING THE
AFOREMENTIONED TIME FRAME. ANOTHER HEAVY RAIN EVENT LOOKS POSSIBLE
WITH WARM LAYER CLOUD DEPTHS AS HIGH AS 4000 METERS AND
PRECIPITABLE WATER NEAR 2 INCHES. LOWER CONFIDENCE WITH SEVERE
POTENTIAL WITH NO SIGNIFICANT AMOUNT OF INSTABILITY AND SHEAR
PRESENT.
FRIDAY THROUGH SUNDAY...TRENDED DRIER FRIDAY INTO SATURDAY AS
EXTENDED MODELS DO NOT HAVE A GOOD HANDLE OF TIMING AND LOCATION
OF WHEN AND IF ANY SHORTWAVE RIDING THE UPPER LEVEL RIDGE WILL
AFFECT THE FORECAST AREA. THUS...WENT WITH LESSER POPS LATE IN THE
PERIOD. PLUS WITH THE DRIER FORECAST...TRENDED WARMER FOR HIGHS
OVER THE WEEKEND AS THINKING LESS CLOUD COVER AND MODELS AT LEAST
HINTING ON STRONGER WAA.
&&
.AVIATION...13/00Z
ISSUED AT 635 PM CDT SUN JUL 12 2015
MAINLY VFR CONDITIONS EXPECTED ACROSS TAF LOCATIONS BUT THERE WILL
BE PATCHY FOG AND ISOLD TO SCT TSRA MAINLY AFFECTING KMCW AND KALO
WHICH WOULD BRING MVFR COND TO THOSE LOCATIONS. KFOD AND KOTM WOULD
BE ON THE FRINGE OF THE ACTIVITY. EASTERN TAF LOCATIONS WOULD HAVE
A THREAT FOR STORMS MAINLY BETWEEN 08Z AND 12Z.
&&
.DMX WATCHES/WARNINGS/ADVISORIES...
HEAT ADVISORY UNTIL 7 PM CDT THIS EVENING FOR ADAIR-ADAMS-
APPANOOSE-AUDUBON-BOONE-CALHOUN-CARROLL-CASS-CLARKE-CRAWFORD-
DALLAS-DAVIS-DECATUR-EMMET-GREENE-GUTHRIE-HUMBOLDT-JASPER-
KOSSUTH-LUCAS-MADISON-MAHASKA-MARION-MONROE-PALO ALTO-POCAHONTAS-
POLK-RINGGOLD-SAC-STORY-TAYLOR-UNION-WAPELLO-WARREN-WAYNE-
WEBSTER.
HEAT ADVISORY FROM NOON TO 7 PM CDT MONDAY FOR ADAIR-ADAMS-
APPANOOSE-AUDUBON-BOONE-CARROLL-CASS-CLARKE-CRAWFORD-DALLAS-
DAVIS-DECATUR-GREENE-GUTHRIE-JASPER-LUCAS-MADISON-MAHASKA-MARION-
MARSHALL-MONROE-POLK-POWESHIEK-RINGGOLD-STORY-TAMA-TAYLOR-UNION-
WAPELLO-WARREN-WAYNE.
&&
$$
SHORT TERM...HARDING
LONG TERM...PODRAZIK
AVIATION...FAB
...UPDATE TO AVIATION FORECAST DISCUSSION...
.SHORT TERM...(THIS EVENING THROUGH MONDAY)
ISSUED AT 326 PM CDT SUN JUL 12 2015
UPPER HIGH REMAINS OVER THE SOUTHERN PLAINS, CENTERED OVER WEST
TEXAS EARLY THIS AFTERNOON, WITH UPPER LOW OVER SOUTHERN
SASKATCHEWAN. UPPER MOISTURE PLUME HAD WORKED ITS WAY NORTH AND EAST
ACROSS THE SOUTHERN ROCKIES AND INTO KANSAS WITH A FEW CUMULUS
RECENTLY NOTED IN HYS/HLC VICINITY NEAR WEAK LOW PRESSURE TROUGH.
DEWPOINTS REMAINED IN THE LOWER TO MIDDLE 70S IN LESS IMPRESSIVE
MIXING, AND TEMPS IN THE LOWER TO MIDDLE 90S.
WILL NEED TO WATCH LOCATIONS TO THE WEST IN THE NEXT FEW HOURS FOR
CONVECTIVE DEVELOPMENT. INHIBITION TO CONVECTION IS LOW THOUGH SO IS
FORCING. DEEP LAYER SHEAR REMAINS DECENT AND COULD KEEP SOME
ORGANIZATION TO STORMS THAT FORM TO THE WEST. LATEST HRRR DEVELOPS
SOME CONVECTION NEAR THE CUMULUS, THOUGH AS IT HAS BEEN RECENTLY,
ALREADY HAS STORMS BY THIS POINT AND IT HAS BEEN OVERZEALOUS ON
PRECIP IN RECENT DAYS. WILL GO AHEAD WITH A SMALL POP IN THE FAR
WEST AROUND 0Z.
NORTHERN UPPER LOW SINKS SOUTHEAST MONDAY, DRAGGING A WEAK COLD
FRONT INTO THE AREA IN THE AFTERNOON. MODELS CONTINUE TO SHOW
VARIOUS IDEAS ON LOW LEVEL THERMODYNAMICS, AND MIXING AGAIN IS NOT
VERY IMPRESSIVE, LIKELY KEEPING DEWPOINTS RATHER HIGH. HAVE LOWERED
MAX TEMPS A BIT BUT THIS STILL SHOULD PROVIDE AN ENVIRONMENT WITH
LIMITED CIN AND, LIKE TODAY, LIMITED FORCING. WITH A MORE DEFINED
BOUNDARY, WILL INCREASE POPS A BIT, WITH AGAIN SOME DEEP-LAYER SHEAR
SUPPORTING MAINLY DOWNBURST WINDS AND PERHAPS HAIL NEAR SEVERE
LEVELS. HEAT HEADLINES REMAIN, WITH APPARENT TEMPS AROUND 110 LIKELY
IN SOUTHERN AND EASTERN AREAS. AGAIN EXACT VALUES HARD TO NAIL DOWN
AND SOME ADJUSTMENTS IN WARNING AREAS COULD BE NEEDED LATER.
.LONG TERM...(MONDAY NIGHT THROUGH SUNDAY)
ISSUED AT 326 PM CDT SUN JUL 12 2015
MODELS SHOW A LOW AMPLITUDE UPPER RIDGE REMAINING ANCHORED NEAR THE
SOUTHERN PLAINS THROUGH THE PERIOD. THIS PLACES THE FORECAST AREA
NEAR THE NORTHERN EDGE OF THE UPPER RIDGE WITH THE POTENTIAL FOR
SHORTWAVE ENERGY TO AFFECT THE REGION. HOWEVER THUNDERSTORM
CHANCES SHOULD BE CONDITIONAL AS MID LEVEL TEMPS WARM TO AROUND
+13C PROVIDING A SUBSTANTIAL CAP OVER THE BOUNDARY LAYER. IN
GENERAL THERE DOES NOT APPEAR TO BE A PERIOD WHERE PRECIP CHANCES
ARE OBVIOUS. THE FORECAST HAS SOME SMALL POPS IN FOR MONDAY NIGHT
AND TUESDAY WITH A WEAK BOUNDARY PROGGED TO BE IN THE AREA. MODELS
HAVE A BETTER DEFINED SHORTWAVE LIFTING THROUGH WESTERN KS AND
CENTRAL NEB ON WEDNESDAY. BECAUSE OF THIS HAVE SOME CHANCE POPS
GOING. THEN SLIGHT CHANCE POPS CONTINUE THROUGH THURSDAY TO
ACCOUNT FOR THE POSSIBILITY FOR SOME LOW LEVEL CONVERGENCE ALONG
A SURFACE TROUGH AXIS. THERE DOES NOT APPEAR TO BE ANY SIGNIFICANT
LIFT OR FORCING PROGGED BY THE MODELS FOR FRIDAY AND SATURDAY, SO
THE FORECAST REMAINS DRY. ANOTHER SURFACE TROUGH MAY MOVE INTO
EASTERN KS FOR SUNDAY SO HAVE SOME SLIGHT CHANCE POPS.
THE CENTER OF THE THERMAL RIDGE BACKS OFF TO THE SOUTHWEST BY
TUESDAY. HOWEVER THE FORECAST AREA IS LIKELY TO REMAIN WITHIN THE
THERMAL RIDGE AXIS THROUGH THE EXTENDED SO TEMPS ARE LIKELY TO
REMAIN HOT WHICH IS NOT UNCOMMON FOR THIS TIME OF YEAR. IN GENERAL
HAVE HIGHS IN THE 90S WITH LOWS IN THE LOWER AND MID 70S THROUGH
NEXT WEEKEND. WHILE THE MAGNITUDE OF THE HEAT MAY NOT BE HAS
EXTREME AS WE ARE EXPECTING TOMORROW, AFTERNOON HEAT INDICES ARE
LIKELY TO REMAIN AROUND 100 FOR THE FORESEEABLE FUTURE.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z MONDAY EVENING)
ISSUED AT 618 PM CDT SUN JUL 12 2015
VFR CONDITIONS ARE EXPECTED THROUGHOUT THE PERIOD. HAVE KEPT WIND
SHEAR IN THE TAF ALTHOUGH IT LOOKS LIKE CONDITIONS WILL BE MARGINAL
DUE TO WINDS STAYING ABOVE 5KTS AT THE SURFACE OVERNIGHT. THERE IS
A SMALL CHANCE FOR STORMS AFTER 21Z TOMORROW, BUT SINCE THAT IS AT
THE VERY TAIL END OF THE PERIOD HAVE LEFT THEM OUT AT THIS TIME.
&&
.TOP WATCHES/WARNINGS/ADVISORIES...
EXCESSIVE HEAT WARNING FROM NOON TO 9 PM CDT MONDAY FOR KSZ012-
024-026-038>040-054>056-058-059.
HEAT ADVISORY UNTIL NOON CDT MONDAY FOR KSZ012-024-026-038>040-
054>056-058-059.
HEAT ADVISORY UNTIL 9 PM CDT MONDAY FOR KSZ008>011-020>023-
034>037.
&&
$$
SHORT TERM...65
LONG TERM...WOLTERS
AVIATION...HELLER
AREA FORECAST DISCUSSION
NWS TOPEKA KS
327 PM CDT SAT JUL 11 2015
.SHORT TERM...(THIS EVENING THROUGH SUNDAY)
ISSUED AT 327 PM CDT SAT JUL 11 2015
19Z WATER VAPOR IMAGERY SHOWS THE CENTER OF AN UPPER RIDGE NEAR THE
ARLATX REGION. MEANWHILE THERE WERE SEVERAL WAVES OVER THE WEST AND
NORTHERN PLAINS. ONE OF THESE WAVES MOVING ON SHORE OVER THE
SOUTHERN CA COAST. PROFILER DATA SUGGESTS THERE MIGHT BE A WEAK VORT
MAX OVER THE TX PANHANDLE LIFTING NORTHEAST AS WELL. AT THE SURFACE,
A WARM FRONT WAS ANALYZED FROM NEAR PHILLIPSBURG KS TO NORTH OF
HEBRON AND INTO NORTHERN MO.
FOR THIS EVENING, THE MAIN CONCERN IS WHETHER LOW LEVEL CONVERGENCE
WILL BE ENOUGH FOR AN ISOLATED STORM OR TWO TO DEVELOP ALONG THE
WARM FRONT. THERE CERTAINLY IS ENOUGH INSTABILITY ALONG THE BOUNDARY
FOR STORMS TO FORM, AND DEEP LAYER SHEAR OF 30 TO 35 KTS COULD
SUPPORT SOME ORGANIZATION TO THE UPDRAFTS. THE HRRR IS THE ONLY
SOLUTION SHOWING ANY DEVELOPMENT ALONG THE WARM FRONT AND BASED ON
LATEST VISIBLE SATELLITE, IT APPEARS CONVERGENCE ALONE MAY NOT BE
ENOUGH TO GET STORMS GOING. THERE REMAINS SOME WILDCARDS THOUGH. THE
HRRR ALSO WANTS TO DEVELOP AN MCS AND BRING IT INTO NORTHERN CENTRAL
KS AFTER MIDNIGHT. WITH STORMS ALREADY FORMING OVER THE HIGH PLAINS,
THIS MAY BE A LITTLE MORE PLAUSIBLE. ISENTROPIC SURFACES SHOW SOME
LIFT THROUGH THE NIGHT AS THE LOW LEVEL JET INCREASES, HOWEVER THERE
IS NOT A LOT OF SATURATED AIR BEING LIFTED. SO I DON`T HAVE A GOOD
FEELING FOR WHETHER STORMS WILL HOLD TOGETHER OFF THE HIGHER TERRAIN
AND I THINK THERE IS NOT ENOUGH MOISTURE FOR ISENTROPIC LIFT ALONE
TO CAUSE SOME ELEVATED STORMS. IN THE END HAVE KEPT A SLIGHT CHANCE
FOR STORMS ACROSS THE NORTHERN COUNTIES IN CASE SOMETHING DEVELOPS
THIS AFTERNOON OR MOVES IN FROM THE WEST. LOWS TONIGHT SHOULD ONLY
FALL INTO THE LOWER AND MID 70S AS SOUTHERLY WINDS CONTINUE TO BRING
WARM AIR NORTH.
FOR SUNDAY, MODELS INDICATE A LACK OF LARGE SCALE FORCING WHILE 700
MB TEMPS WARM THROUGH THE DAY. SO UNLESS SOMETHING UNEXPECTED
HAPPENS, LIKE AN MCS MOVING ACROSS NORTHERN KS IN THE MORNING, THINK
THE STRENGTHENING CAP SHOULD PRECLUDE PRECIP CHANCES. MODELS SHOW
LIMITED MIXING OF THE BOUNDARY LAYER ACROSS EASTERN KS WHILE NORTH
CENTRAL KS COULD MIX TO NEAR 800MB. ADDITIONALLY THERE IS SOME DRY
AIR MOVING IN AT 850 WITH DEWPOINT DEPRESSIONS NEAR 15C. SO ACROSS
EASTERN KS HIGHS ARE EXPECTED TO BE IN THE LOWER AND MID 90S BUT
WITH LESS MIXING SO DEWPOINTS SHOULD REMAIN IN THE LOWER 70S. TEMPS
ACROSS NORTH CENTRAL KS SHOULD APPROACH 100 WITH DEEPER MIXING, BUT
SHOULD MIX SOME OF THE DRYER AIR TO THE SURFACE. IN THE END, HEAT
INDICES ARE STILL EXPECTED TO BE AROUND 105 SUNDAY AFTERNOON ACROSS
THE ENTIRE AREA, SO WILL MAINTAIN THE HEAT ADVISORY AS IS.
.LONG TERM...(SUNDAY NIGHT THROUGH SATURDAY)
ISSUED AT 327 PM CDT SAT JUL 11 2015
HEAT CONTINUES TO BE THE MAIN CONCERN THROUGH MUCH OF THE REMAINDER
OF THE FORECAST. WEAK BOUNDARY LOOKS TO BE A BIT FASTER IN ITS
SOUTHEASTWARD TRACK THROUGH THE AREA MONDAY AND MAY KEEP HEAT INDEX
VALUES FROM GETTING TOO FAR ABOVE 100, BUT WILL KEEP THE ADVISORY
GOING. HEAT INDICES STILL LOOK TO BE WELL INTO ADVISORY AND PERHAPS
WARNING LEVELS ALONG AND AHEAD OF THE FRONT THOUGH AS IS USUAL AT
THIS RANGE, CONFIDENCE IN TEMPS AND DEWPOINTS IS NOT TERRIBLY HIGH
AND JUST HOW MUCH THE POOLED MOISTURE CAN MIX OUT BEING THE PRIMARY
IMPACT ON APPARENT TEMPS. THIS ALSO LEADS TO INSTABILITY/CAP VALUES
ALONG THE BOUNDARY, THOUGH STILL SEEMS POSSIBLE FOR ISOLATED TO
SCATTERED CONVECTION DESPITE WEAK CONVERGENCE. NORTHWEST MID/UPPER
FLOW LEADS TO MODERATE SHEAR AND COULD SUPPORT SOME STORM
ORGANIZATION FOR NEAR SEVERE HAIL ALONG WITH WIND POTENTIAL. HAVE
TRIMMED PRECIP CHANCES IN MAINLY NORTHERN AREAS INTO TUESDAY WITH
THE QUICKER FRONT TIMING WITH MORE MORE WIDESPREAD THOUGH STILL
MODEST RELIEF TO THE HEAT, ENOUGH TO KEEP ANY EXTENSION TO THE HEAT
ADVISORY IN CHECK.
THERE APPEARS TO BE DECENT AGREEMENT IN A SLOW-MOVING UPPER WAVE
TOPPING THE RIDGE AND ENTERING THE CENTRAL HIGH PLAINS LATE TUESDAY,
WITH SOUTHEAST LOW LEVEL FLOW IN PLACE AHEAD OF IT FOR DECENT
THUNDERSTORM CHANCES L0CALLY LATE TUESDAY NIGHT INTO WEDNESDAY
NIGHT. HAVE MOST LOCATIONS SOMEWHAT COOLER WEDNESDAY IN RESPONSE,
WITH RIDGE REGAINING SOME STRENGTH NORTHEASTWARD INTO THE MIDWEST
LATE IN THE WEEK LIKELY ALLOWING FOR A WARMING TREND IN THE LATE
WEEK. DEWPOINTS AT TO ABOVE THE 70 DEGREE MARK COULD EASILY BRING
ABOUT MORE HEAT HEADLINE POTENTIAL BY THEN.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON)
ISSUED AT 1220 PM CDT SAT JUL 11 2015
WITH LIMITED FORCING AND THE FOCUS FOR LOW LEVEL CONVERGENCE
HAVING LIFTED NORTH OF THE TERMINALS, THINK DRY WEATHER WILL
PREVAIL WITH VFR CONDITIONS. WILL NEED TO WATCH THE LOW LEVEL JET
OVERNIGHT AS MODELS PROG 30-35KT AT THE TOP OF THE NOCTURNAL
INVERSION. AT THIS TIME, THE SURFACE PRESSURE GRADIENT MAY BE
STRONG ENOUGH TO KEEP THE BOUNDARY LAYER FROM DECOUPLING. BECAUSE
OF THIS CONFIDENCE IN LLWS DEVELOPING IS TO LOW TO INCLUDE A
MENTION JUST YET.
&&
.TOP WATCHES/WARNINGS/ADVISORIES...
HEAT ADVISORY FROM 11 AM SUNDAY TO 9 PM CDT MONDAY FOR
KSZ008>012-020>024-026-034>040-054>056-058-059.
&&
$$
SHORT TERM...WOLTERS
LONG TERM...65
AVIATION...WOLTERS
AREA FORECAST DISCUSSION
NWS PADUCAH KY
329 PM CDT SAT JUL 11 2015
.SHORT TERM...(THIS EVENING THROUGH MONDAY)
ISSUED AT 328 PM CDT SAT JUL 11 2015
THE INFLUENCE OF THE SOUTHEAST U.S. HIGH PRESSURE RIDGE FINALLY
KICKED IN ACROSS THE WFO PAH FORECAST AREA LAST EVENING AND TODAY.
MOST OF THE WFO PAH FORECAST AREA SHOULD REMAIN DRY THROUGH LATE
AFTERNOON UNDER THE SLIGHT LOW LEVEL SUBSIDENCE INVERSION BUILDING
NORTHEAST THROUGH THE AREA. HOWEVER...THERE REMAINS A SHARP THERMAL
GRADIENT ACROSS THE INTERSTATE 64 CORRIDOR IN SOUTHEAST
ILLINOIS...BENDING SOUTHEAST OVER SOUTHWEST INDIANA AND THE EASTERN
PENNYRILE REGION OF WEST KENTUCKY. THIS AREA IS CURRENTLY ALONG AND
NORTH OF THE OBSERVED SURFACE WARM FRONT AT 1PM CDT SPRAWLED OVER
THE NORTHEAST THIRD OF THE WFO PAH FORECAST AREA.
FOR TONIGHT...THE MESOSCALE CONVECTIVE SYSTEM CURRENTLY OVER WEST
CENTRAL ILLINOIS WILL LIKELY SEND OUTFLOWS AND SOME UPSHEAR LIFT
ALONG AND NORTH OF I-64 LATE THIS AFTERNOON. THIS HAS THE POTENTIAL
TO PRODUCE ISOLATED THUNDERSTORM THAT MAY APPROACH SEVERE LIMITS
CLOSE TO THE WFO PAH FORECAST AREA. THE MAIN CONCERN WILL BE
ELEVATED STORMS OVERNIGHT OVER PARTS OF SOUTHWEST INDIANA.
INTRODUCED A MENTION OF LOCALLY HEAVY RAIN INTO THE GRIDS FOR PARTS
OF PIKE...WARRICK AND SPENCER COUNTIES IN SOUTHWEST INDIANA. IN
COLLABORATION WITH NWS INDIANAPOLIS...DECIDED AGAINST A FLASH FLOOD
WATCH IN THIS AREA GIVEN THE LIMITED COVERAGE IN SPACE AND TIME. IT
WILL STILL NEED TO BE MONITORED OVERNIGHT.
FOR SUNDAY...ADDED A MENTION OF GUSTY WINDS AND HEAVY RAIN TO THE
GRIDS FOR ANY THUNDERSTORMS THAT DEVELOP OVER THE NORTHEAST HALF OF
THE WFO PAH FORECAST AREA LATE SUNDAY MORNING AND AFTERNOON. VERY
ROBUST CAPE FOR UPDRAFTS WITH CONVECTIVE TEMPERATURES SUFFICIENT FOR
INITIATION. GIVEN THE SUBTLE INVERSION IN PLACE...THERE MAY BE
ENOUGH MIXING/DOWNDRAFT CAPE TO SUPPORT STRONG WIND
GUSTS...ESPECIALLY DURING THE AFTERNOON. THERE IS SUPPORT FOR SOME
DAMAGING WIND GUSTS (AND POSSIBLY A MICROBURST OR TWO) WITH THIS
REGIME IN THE AREA OUTLOOKED BY SPC FOR SUNDAY. THE ONLY
COMPLICATING FACTOR WILL BE ANY DELAY IN REACHING CONVECTIVE
TEMPERATURE NEAR THE SURFACE OR IN THE BOUNDARY LAYER DUE TO LEFT
OVER CLOUD DEBRIS FROM OVERNIGHT CONVECTION.
FOR MONDAY...BEST CHANCES FOR SEVERE WILL EXPAND WITH SUFFICIENT
CAPE/SHEAR FOR MULTICELL STORMS DEFINITELY CAPABLE OF LARGE
HAIL...DAMAGING WINDS AND POSSIBLY A TORNADO OR TWO EAST OF THE
MISSISSIPPI RIVER...ESPECIALLY DURING THE AFTERNOON AND EVENING.
LEANED CLOSER TO THE 3KM HRRR FOR THE EXTREMELY SHORT TERM
CONVECTIVE TRENDS...BLENDING TOWARD THE NAM-WRF GUIDANCE IN THE
LONGER TIME PERIODS.
HEAT INDEX VALUES WILL COME CLOSE TO HEAT ADVISORY CRITERIA ON
SUNDAY...AND POSSIBLY REACHING INTO HEAT ADVISORY CRITERIA OVER
PARTS OF SOUTHEAST MISSOURI AND SOUTHWEST ILLINOIS ON MONDAY.
HOWEVER...GIVEN CLOUD DEBRIS AND WINDS...WILL HOLD OFF REGARDING ANY
ADVISORY AT THIS TIME. WILL HIGHLIGHT IN A HAZARDOUS WEATHER OUTLOOK
AND A SPECIAL WEATHER STATEMENT FOR NOW.
.LONG TERM...(MONDAY NIGHT THROUGH SATURDAY)
ISSUED AT 328 PM CDT SAT JUL 11 2015
AT THE BEGINNING OF THE EXTENDED FORECAST PERIOD...A SFC FRONTAL
BOUNDARY SHOULD ARRIVE IN THE NE QUADRANT OF THE AREA...DRIVEN BY
A MID LEVEL SHRTWV AND FAST NWRLY FLOW ALOFT. THE MED RANGE
MODELS SUGGEST SOME SEVERE WEATHER IS POSSIBLE WITH THIS SYSTEM
TUE. PCPN CHANCES (HIGHEST IN THE SERN QUADRANT) ASSOCIATED WITH
THIS FORCING WILL WANE TUE NIGHT AS THE MID/UPPER FLOW GOES
SLIGHTLY ANTI-CYCLONIC...LEAVING WED DRY. BY MIDDAY THU...A
SECOND SFC BOUNDARY SHOULD BE IN THE VICINITY OF THE PAH FORECAST
AREA...PROVIDING LOW LEVEL FORCING FOR SCATTERED SHOWER AND TSTM
DEVELOPMENT ACROSS THE ENTIRE REGION...EXCEPT PERHAPS THE FAR WEST
(PARTS OF SERN MO) CLOSER TO A DOMINANT SRN CONUS RIDGE. SOME
ATMOSPHERIC INSTABILITY WILL BE PROVIDED BY A MINOR ENERGY IMPULSE
IN THE WESTERLIES JUST TO THE NORTH OF IT. THIS EVENT SHOULD END
THU NIGHT AS THE FRONTAL BOUNDARY EXITS THE REGION AND THE ANTI-
CYCLONIC FLOW ALOFT DOMINATES AGAIN.
FOR THE REST OF THE WEEK...RAIN-FREE CONDITIONS ARE EXPECTED.
MEANWHILE...HEAT INDICES ARE EXPECTED TO FLIRT WITH THE 105 DEGREE
MARK IN SERN MO EARLY IN THE PERIOD. LATER IN THE PERIOD...HEAT
INDICES BETWEEN 100 AND 105 SHOULD BECOME COMMON ACROSS THE ENTIRE
REGION.
&&
.AVIATION...
ISSUED AT 328 PM CDT SAT JUL 11 2015
A FRONTAL BOUNDARY WILL SLOWLY PASS NEWD THROUGH THE NERN HALF OF
THE REGION TODAY. GENERALLY LIGHT WINDS SHOULD BE MOSTLY OUT OF THE
SW DURING THE DAYLIGHT HOURS BEHIND THE FRONT...AND WILL BE MORE
VARIABLE IN DIRECTION IN THE VICINITY OF THE FRONT. THE BEST CHANCE
OF PCPN WILL BE IN THE NERN QUADRANT OF THE REGION OVERNIGHT...AS A
POSSIBLE TSTM COMPLEX MAY MOVE THROUGH. THERE WAS SOME MODEL
DISAGREEMENT ABOUT WHETHER THIS WILL HAPPEN...SO FOR NOW
SHOWERS/TSTMS WERE LEFT OUT OF THE KEVV/KOWB TAFS. THIS SCENARIO
WILL BE RE-EVALUATED DURING THIS AFTERNOON. SOME IFR FOG IS STILL
POSSIBLE OVERNIGHT AT KPAH.
&&
.PAH WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
MO...NONE.
IN...NONE.
KY...NONE.
&&
$$
SHORT TERM...DB
LONG TERM...SMITH
AVIATION...DB
AREA FORECAST DISCUSSION
NWS LAKE CHARLES LA
1232 PM CDT SAT JUL 11 2015
.DISCUSSION...
FOR THE 19Z TAF PACKAGE.
&&
.AVIATION...
SCATTERED CU/STRATOCU ACROSS THE REGION PER VISIBLE SATELLITE
IMAGERY...WITH RADAR IMAGERY SHOWING ISOLATED SHOWERS AND A TSTM
OR TWO OVER THE GULF WATERS AND COASTAL COUNTIES/PARISHES. VFR IS
EXPECTED TO PREVAIL...WITH CONVECTION FCST TO REMAIN ISOLATED IN
NATURE AS DIURNAL INSTABILITY BATTLES AGAINST MASS SUBSIDENCE
ASSOCIATED WITH THE DEEP LAYER RIDGING IN PLACE. INSERTED VCSH AT
THE I-10 TERMINALS WHERE HIGHEST...ALBEIT STILL LOW...PROBABILITY
RESIDES.
13
&&
.PREV DISCUSSION... /ISSUED 1047 AM CDT SAT JUL 11 2015/
DISCUSSION...MORNING LCH SOUNDING SHOWING PWAT A FEW TENTHS BELOW
THAT OF YESTERDAY MORNING. STILL SUFFICIENT MOISTURE FOR ISOLATED
AFTERNOON CONVECTION. RADAR JUST NOW DEPICTING A FEW PINPOINT
SHOWERS INLAND. FORECAST ON TRACK WITH LOW END POPS. NO UPDATE
COMING.
PREV DISCUSSION... /ISSUED 650 AM CDT SAT JUL 11 2015/
AVIATION...RIDGING WILL BUILD FROM THE MID LEVELS INTO THE UPPER
LEVELS. ALTHOUGH HRRR IS SHOWING WIDELY SCATTERED TSTM ACTIVITY
THIS AFTERNOON, WILL OPT TO NOT MENTION IN THE TAFS AS THE
COVERAGE LOOKS TO BE ISOLATED FROM ALL THE CONVECTIVE INHIBITION.
VFR.
SWEENEY
PREV DISCUSSION... /ISSUED 240 AM CDT SAT JUL 11 2015/
DISCUSSION...
SFC HIGH PRESSURE CONTINUES RIDGING ACROSS THE GULF...WITH A S TO
SE FLOW ACROSS THE REGION. RADAR SHOWING A FEW NOCTURNAL SHRA
ACROSS THE COASTAL WATERS MOVING ASHORE ACROSS THE COASTAL
PARISHES/COUNTIES AND DISSIPATING.
LIMITED MOISTURE ALOFT AND FOCUS WILL LIMITED CONVECTION TO ISO
DURING THE AFTERNOON HOURS...WITH THE ONGOING 20% STILL LOOKING
GOOD FOR THE FORECAST. LOWER/MID 90S FOR HIGHS EXPECTED.
THE FORECAST FOR NEXT WEEK LOOKS TO CONTINUE THE HOT AND DRY
CONDITIONS DUE TO BUILDING HIGH PRESSURE AT THE SFC AND ALOFT. THE
RIDGE WILL INTENSIFY A BIT TOWARDS MON-WED...LIMITING CONVECTION
EVEN MORE...BUT TEMPS EXPECTED TO BUMP UP A COUPLE OF DEGREES.
MODEL BLEND ONLY SHOWS A SLIGHT INCREASE IN MOISTURE TOWARDS
FRI...WITH 20% EXPECTED. OTHERWISE...SLIGHTLY ABOVE NORMAL TEMPS
EXPECTED THRU THE PERIOD...MOST NOTABLE FOR LOWS.
DML
MARINE...
SURFACE HIGH PRESSURE RIDGING WESTWARD ACROSS THE NORTHWEST GULF
OF MEXICO WILL CONTINUE TO PROVIDE A LIGHT SOUTHERLY FLOW OVER
THE NEXT SEVERAL DAYS.
&&
.PRELIMINARY POINT TEMPS/POPS...
AEX 94 75 95 76 / 20 10 10 10
LCH 91 77 92 77 / 20 10 10 10
LFT 92 75 93 76 / 20 10 10 10
BPT 91 77 92 76 / 20 10 10 10
&&
.LCH WATCHES/WARNINGS/ADVISORIES...
LA...NONE.
TX...NONE.
GM...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS LAKE CHARLES LA
1047 AM CDT SAT JUL 11 2015
.DISCUSSION...MORNING LCH SOUNDING SHOWING PWAT A FEW TENTHS BELOW
THAT OF YESTERDAY MORNING. STILL SUFFICIENT MOISTURE FOR ISOLATED
AFTERNOON CONVECTION. RADAR JUST NOW DEPICTING A FEW PINPOINT
SHOWERS INLAND. FORECAST ON TRACK WITH LOW END POPS. NO UPDATE
COMING.
&&
.PREV DISCUSSION... /ISSUED 650 AM CDT SAT JUL 11 2015/
AVIATION...RIDGING WILL BUILD FROM THE MID LEVELS INTO THE UPPER
LEVELS. ALTHOUGH HRRR IS SHOWING WIDELY SCATTERED TSTM ACTIVITY
THIS AFTERNOON, WILL OPT TO NOT MENTION IN THE TAFS AS THE
COVERAGE LOOKS TO BE ISOLATED FROM ALL THE CONVECTIVE INHIBITION.
VFR.
SWEENEY
PREV DISCUSSION... /ISSUED 240 AM CDT SAT JUL 11 2015/
DISCUSSION...
SFC HIGH PRESSURE CONTINUES RIDGING ACROSS THE GULF...WITH A S TO
SE FLOW ACROSS THE REGION. RADAR SHOWING A FEW NOCTURNAL SHRA
ACROSS THE COASTAL WATERS MOVING ASHORE ACROSS THE COASTAL
PARISHES/COUNTIES AND DISSIPATING.
LIMITED MOISTURE ALOFT AND FOCUS WILL LIMITED CONVECTION TO ISO
DURING THE AFTERNOON HOURS...WITH THE ONGOING 20% STILL LOOKING
GOOD FOR THE FORECAST. LOWER/MID 90S FOR HIGHS EXPECTED.
THE FORECAST FOR NEXT WEEK LOOKS TO CONTINUE THE HOT AND DRY
CONDITIONS DUE TO BUILDING HIGH PRESSURE AT THE SFC AND ALOFT. THE
RIDGE WILL INTENSIFY A BIT TOWARDS MON-WED...LIMITING CONVECTION
EVEN MORE...BUT TEMPS EXPECTED TO BUMP UP A COUPLE OF DEGREES.
MODEL BLEND ONLY SHOWS A SLIGHT INCREASE IN MOISTURE TOWARDS
FRI...WITH 20% EXPECTED. OTHERWISE...SLIGHTLY ABOVE NORMAL TEMPS
EXPECTED THRU THE PERIOD...MOST NOTABLE FOR LOWS.
DML
MARINE...
SURFACE HIGH PRESSURE RIDGING WESTWARD ACROSS THE NORTHWEST GULF
OF MEXICO WILL CONTINUE TO PROVIDE A LIGHT SOUTHERLY FLOW OVER
THE NEXT SEVERAL DAYS.
&&
.PRELIMINARY POINT TEMPS/POPS...
AEX 94 75 95 76 / 20 10 10 10
LCH 91 77 92 77 / 20 10 10 10
LFT 92 75 93 76 / 20 10 10 10
BPT 91 77 92 76 / 20 10 10 10
&&
.LCH WATCHES/WARNINGS/ADVISORIES...
LA...NONE.
TX...NONE.
GM...NONE.
&&
$$
PUBLIC...23
AREA FORECAST DISCUSSION
NWS LAKE CHARLES LA
650 AM CDT SAT JUL 11 2015
.AVIATION...RIDGING WILL BUILD FROM THE MID LEVELS INTO THE UPPER
LEVELS. ALTHOUGH HRRR IS SHOWING WIDELY SCATTERED TSTM ACTIVITY
THIS AFTERNOON, WILL OPT TO NOT MENTION IN THE TAFS AS THE
COVERAGE LOOKS TO BE ISOLATED FROM ALL THE CONVECTIVE INHIBITION.
VFR.
SWEENEY
&&
.PREV DISCUSSION... /ISSUED 240 AM CDT SAT JUL 11 2015/
DISCUSSION...
SFC HIGH PRESSURE CONTINUES RIDGING ACROSS THE GULF...WITH A S TO
SE FLOW ACROSS THE REGION. RADAR SHOWING A FEW NOCTURNAL SHRA
ACROSS THE COASTAL WATERS MOVING ASHORE ACROSS THE COASTAL
PARISHES/COUNTIES AND DISSIPATING.
LIMITED MOISTURE ALOFT AND FOCUS WILL LIMITED CONVECTION TO ISO
DURING THE AFTERNOON HOURS...WITH THE ONGOING 20% STILL LOOKING
GOOD FOR THE FORECAST. LOWER/MID 90S FOR HIGHS EXPECTED.
THE FORECAST FOR NEXT WEEK LOOKS TO CONTINUE THE HOT AND DRY
CONDITIONS DUE TO BUILDING HIGH PRESSURE AT THE SFC AND ALOFT. THE
RIDGE WILL INTENSIFY A BIT TOWARDS MON-WED...LIMITING CONVECTION
EVEN MORE...BUT TEMPS EXPECTED TO BUMP UP A COUPLE OF DEGREES.
MODEL BLEND ONLY SHOWS A SLIGHT INCREASE IN MOISTURE TOWARDS
FRI...WITH 20% EXPECTED. OTHERWISE...SLIGHTLY ABOVE NORMAL TEMPS
EXPECTED THRU THE PERIOD...MOST NOTABLE FOR LOWS.
DML
MARINE...
SURFACE HIGH PRESSURE RIDGING WESTWARD ACROSS THE NORTHWEST GULF
OF MEXICO WILL CONTINUE TO PROVIDE A LIGHT SOUTHERLY FLOW OVER
THE NEXT SEVERAL DAYS.
&&
.PRELIMINARY POINT TEMPS/POPS...
AEX 94 75 95 76 / 20 10 10 10
LCH 91 77 92 77 / 20 10 10 10
LFT 92 75 93 76 / 20 10 10 10
BPT 91 77 92 76 / 20 10 10 10
&&
.LCH WATCHES/WARNINGS/ADVISORIES...
LA...NONE.
TX...NONE.
GM...NONE.
&&
$$
AVIATION...11
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
728 PM EDT SUN JUL 12 2015
.SHORT TERM...(THIS EVENING THROUGH MONDAY)
ISSUED AT 351 PM EDT SUN JUL 12 2015
THE UPPER RIDGE THAT HAS BEEN OVER THE UPPER GREAT LAKES REGION WILL
BREAK DOWN THROUGH THE SHORT TERM PERIOD...SETTING THE STAGE TO A
RETURN TO BELOW NORMAL TEMPERATURES FOR THE TUESDAY-THURSDAY TIME
FRAME. THIS BREAKDOWN WILL BE DRIVEN BY THE SEVERAL EMBEDDED WAVES
ASSOCIATED WITH THE UPPER TROUGH OVER SOUTHERN ALBERTA/SASKATCHEWAN
AND MONTANA. A BROAD 1000MB SURFACE LOW IS LOCATED BELOW THIS UPPER
LOW AND A TROUGH STRETCHES SOUTHEAST INTO THE EASTERN DAKOTAS. THESE
FEATURES WILL BE THE MAIN FOCUS FOR CONVECTION LATE THIS AFTERNOON
INTO MONDAY. TO THE EAST OF THOSE FEATURES AND OVER UPPER
MICHIGAN...A HIGH PRESSURE RIDGE HAS BEEN WEAKENING AND DEPARTING
THE AREA TO THE SOUTHEAST. SOUTHERLY FLOW AROUND THIS HIGH CONTINUES
TO LEAD TO THE WARM/HUMID CONDITIONS ACROSS THE U.P....WITH
AFTERNOON TEMPERATURES IN THE LOWER 80S AND DEWPOINTS IN THE UPPER
50S AND LOWER 60S. WITH SUNSHINE TO START THE DAY...DIURNAL HEATING
HAS PRODUCED A CU FIELD OVER THE INTERIOR WEST...WHILE THE LAKE
BREEZE OVER THE EAST OFF LAKE MICHIGAN (KISQ ONLY 72 AT 3PM) HAS
STABILIZED THAT AREA AND KEEP CONDITIONS MOSTLY SUNNY. THUNDERSTORMS
HAVE CONTINUED TO DEVELOP IN THE NORTHEAST EDGE OF THE 850MB WARM
AIR ADVECTION IN NORTHEAST MINNESOTA AND NORTHWEST WISCONSIN...WHICH
IS NOW PUSHING SHOWERS AND THUNDERSTORMS EAST ACROSS WESTERN LAKE
SUPERIOR. THE TREND HAS BEEN FOR THEM TO DIMINISH AS THEY PUSH EAST
INTO THE WEAKER MID LEVEL LAPSE RATES AND AWAY FROM THE BETTER
FORCING. EXPECT THAT TO ALSO OCCUR WITH THE STORMS IN WESTERN LAKE
SUPERIOR AND HAVE SEEN A DOWNWARD TREND ON RADAR AND LIGHTNING OVER
THE LAST 15-30MIN. HAVE SEEN A FEW BRIEF SHOWERS DEVELOP OVER
WESTERN/CENTRAL UPPER MICHIGAN THIS AFTERNOON...BUT OVERALL THEY
HAVE BEEN FAIRLY SMALL AND VERY ISOLATED. EXPECT THAT ISOLATED
POTENTIAL TO CONTINUE...INHIBITED BY THE WEAKER MID LEVEL LAPSE
RATES AND RAP SOUNDINGS SHOWING SOME CAPPING NEAR 725MB. IF
SOMETHING COULD GET GOING WOULD LARGELY EXPECT BRIEF HEAVY RAIN AND
SMALL HAIL DUE TO THE HIGH FREEZING LEVELS. ANY OF THESE SHOWERS
THAT DO DEVELOP SHOULD DIMINISH AS DIURNAL HEATING IS LOST.
THE FORECAST THEN TURNS TO WHAT WILL OCCUR UPSTREAM IN EASTERN NORTH
DAKOTA AND NORTHWEST MINNESOTA OVER THE NEXT FEW HOURS.
THUNDERSTORMS WILL QUICKLY DEVELOP IN THAT AREA THIS EVENING
(ALREADY STARTING TO SEE DEVELOPMENT SOUTH AND EAST OF FARGO ALONG
THE WARM FRONT) IN ASSOCIATION WITH A SHORTWAVE NOW MOVING THROUGH
CENTRAL NORTH DAKOTA. WHILE THEY WILL BE DISCRETE STORMS
INITIALLY...THE EXPECTATION IS FOR THEM TO DEVELOP SOUTHEAST INTO AN
MCS THROUGH THE NIGHT. AT THIS POINT...THE EXPECTED DEVELOPMENT
LOCATION AND STORM MOTION WOULD MOVE THE STORMS TO THE EAST ACROSS
THE NORTHERN/CENTRAL PORTIONS OF MINNESOTA AND THEN DIVE FARTHER TO
THE SOUTHEAST AS THEY NEAR WESTERN WISCONSIN DUE TO THE SOUTHEAST
POINTING FORWARD PROPAGATING CORFIDI VECTORS AND THE LOCATION OF THE
MUCAPE GRADIENT. WHILE THE STRONGEST STORMS SHOULD STAY TO THE SOUTH
OF THE CWA...STILL THINK THE AREA WILL SEE THE NORTHERN SIDE OF THE
COMPLEX...WHICH WILL PRODUCE SHOWERS AND THUNDERSTORMS (ESPECIALLY
NEAR THE WISCONSIN BORDER OUT WEST). WILL CONTINUE TO SHOW THE
HIGHEST POPS THERE DURING THE OVERNIGHT HOURS AND THEN DIMINISH THEM
AS THE MAIN COMPLEX SLIDES AWAY FROM THE AREA. WILL ADD A MENTION OF
STRONG STORMS PRODUCING GUSTY WINDS FOR THE NORTHERN EDGE OF THE MCS
BRUSHING THE WISCONSIN BORDER.
THE QUESTION THEN TURNS TO WHAT WILL HAPPEN TOMORROW BEHIND THE MCS
THAT MOVES TO THE SOUTH OF THE AREA. THERE STILL WILL BE UPPER LEVEL
SUPPORT FOR SHOWERS/THUNDERSTORMS AS THE UPPER TROUGH ENERGY MOVES
THROUGH THE REGION (ALONG WITH THE SURFACE TROUGH). WILL CONTINUE TO
SHOW CHANCE POPS...LIKELY TIED TO THE COMBINATION OF THE UPPER
TROUGH AND WHAT IS LEFT OVER FROM THE NORTHERN EDGE OF THE MCS. THE
POPS WILL NEED TO BE FINE TUNED TONIGHT ONCE THE MCS HAS SHOWN ITS
LOCATION/MOVEMENT...AS IT WILL LIKELY AFFECT THE LOCATION OF THE
PRECIPITATION TOMORROW. INSTABILITY WILL NOT BE AS STRONG AS
TODAY...MUCAPE VALUES GENERALLY STRUGGLING TO EVEN GET TO 750J/KG
(EXCEPT OVER FAR WESTERN UPPER MICHIGAN)...SO THINK THE THUNDER
CHANCES WILL BE LIMITED BUT STILL KEEP THE CHANCE THERE.
.LONG TERM...(MONDAY NIGHT THROUGH SUNDAY)
ISSUED AT 301 PM EDT SUN JUL 12 2015
NAM SHOWS A TROUGH ON THE WEST COAST...A RIDGE OVER THE
ROCKIES...SHORTWAVE OVER THE UPPER GREAT LAKES 00Z TUE. A COLD FRONT
MOVES THROUGH THE AREA MON NIGHT INTO TUE AND THEN WENT DRY FOR TUE
NIGHT AND WED. OVERALL...DID NOT MAKE TOO MANY CHANGES TO THE GOING
FORECAST FOR TEMPERATURES OR WEATHER.
IN THE EXTENDED...GFS AND ECMWF SHOW A BROAD 500 MB TROUGH IN THE
WESTERN U.S. AND A RIDGE ACROSS THE GULF COAST 12Z THU. THERE IS
ALSO A SHORTWAVE OVER THE NORTHERN PLAINS 12Z THU THAT MOVES INTO
THE UPPER GREAT LAKES 12Z FRI. BEHIND THIS SHORTWAVE...UPPER RIDGING
MOVES INTO THE UPPER GREAT LAKES ON SAT INTO SUN WITH SOME WARMER
AIR TRYING TO GET INTO THE AREA THIS NEXT WEEKEND. SFC FRONTS WILL
BE IN THE AREA WITH THE AREA BEING ON THE BOUNDARY BETWEEN VERY WARM
AND HUMID AIR TO THE SOUTH AND COOLER AND DRIER AIR TO THE NORTH AND
HAVING SOME POPS IN FOR THE EXTENDED SEEMS WARRANTED.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z MONDAY EVENING)
ISSUED AT 728 PM EDT SUN JUL 12 2015
EXPECT VFR CONDITIONS THRU AT LEAST THIS EVNG. BUT THEN ATTENTION WL
TURN TO A CLUSTER OF SHOWERS/TS THAT IS LIKELY TO DEVELOP OVER
NCNTRL MN TNGT. RIGHT NOW...IT APPEARS THE BULK OF THIS CLUSTER WL
SLIDE SE INTO WI BUT AT LEAST SKIM THE BORDER WITH UPR MI. ADDED A
SPECIFIC MENTION OF FCST TS IN THE EARLY MRNG HRS AT IWD...THE
LOCATION MOST LIKELY TO BE IMPACTED BY THE CLUSTER. MORE SHOWERS AND
PERHAPS A TS ON THE NRN FRINGE OF THE STRONGER STORMS TO THE S WL
IMPACT CMX AND SAW LATE. WITH THESE SHOWERS...MORE HUMID AIR AND
NOCTURNAL COOLING...MVFR AND PERHAPS IFR CONDITIONS ARE LIKELY AT
ALL 3 LOCATIONS. THESE SHOWERS ALONG WITH A GOOD CHANCE OF AT LEAST
MVFR CONDITIONS ARE LIKELY TO IMPACT THE SITES THRU THE MRNG. WITH
CONTINUED DAYTIME HEATING...EXPECT A GRADUAL IMPROVEMENT TO VFR IN
THE AFTN.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 351 PM EDT SUN JUL 12 2015
A WEAKENING RIDGE COMBINED WITH AN LOW PRESSURE SYSTEM MOVING FROM
SOUTHEAST SASKATCHEWAN THROUGH SOUTHERN WISCONSIN WILL KEEP WINDS
BELOW 20KTS THROUGH MONDAY EVENING. A COLD FRONT WILL DROP SOUTH
ACROSS LAKE SUPERIOR LATE MONDAY NIGHT...SHIFTING THE WINDS TO A
NORTHERLY DIRECTION...BUT SPEEDS WILL LARGELY STAY BELOW 20KTS. A
HIGH PRESSURE RIDGE WILL THEN MOVE OVER LAKE SUPERIOR FOR TUESDAY
NIGHT THROUGH WEDNESDAY NIGHT AND KEEP WINDS LIGHT.
AREAS OF FOG CONTINUE TO AFFECT LAKE SUPERIOR TODAY AS WARM...MOIST
AIR IS FLOWING OVER THE RELATIVELY COOL OPEN WATERS OF LAKE
SUPERIOR. THIS MORNING THE FOG WAS CONFINED TO THE NORTHERN HALF
OF THE LAKE...BUT LIGHT NORTHEASTERLY FLOW HAS EDGED THAT FOG A
LITTLE FARTHER TO THE SOUTH. SEVERAL SHIP OBS TODAY INDICATED THE
FOG WAS DENSE AT TIMES...SO DECIDED TO ISSUE A MARINE DENSE FOG
ADVISORY FOR THE NORTHERN PORTIONS OF LAKE SUPERIOR INTO MONDAY
NIGHT. WITH THE CONTINUED WARM AND MOIST AIR...ALONG WITH
SOME RAIN TONIGHT INTO MONDAY...WILL CONTINUE TO SHOW AREAS OF FOG
THROUGH MONDAY NIGHT. THEN AS DRIER AIR ARRIVES LATER TUESDAY INTO
TUESDAY NIGHT BEHIND THE COLD FRONT...EXPECT THE FOG POTENTIAL TO
DIMINISH.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
DENSE FOG ADVISORY UNTIL 8 AM EDT TUESDAY FOR LSZ263-264-266.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...SRF
LONG TERM...07
AVIATION...KC
MARINE...SRF
AREA FORECAST DISCUSSION
NWS GAYLORD MI
133 PM EDT SAT JUL 11 2015
.UPDATE...
ISSUED AT 1018 AM EDT SAT JUL 11 2015
ANOTHER IDEAL MORNING IN NORTHERN MI. SKIES ARE JUST ABOUT
CLEAR...WITH SOME HIGH-BASED CU IN THE GD TRAV BAY REGION...AND
IN PARTS OF CENTRAL UPPER MI. THIS IS ASSOCIATED WITH A SUBTLE
WARM FRONT ADVANCING EAST NEAR MUNISING/ISQ...AND IS OCCURRING IN
THE STEEP LAPSE RATES AT THE TOP OF YESTERDAYS MIXED LAYER. THERE
IS STRONG INVERSION PRESENT ABOVE THIS. PER 12Z OBSERVED
SOUNDINGS...700MB TEMPS ARE 9C AT APX...10C AT GRB. THIS IS NOT
SURPRISING...GIVEN A 500MB SHORTWAVE RIDGE AXIS WILL BE DEAD
OVERHEAD THIS AFTERNOON.
SO IT WILL TAKE SOME SERIOUS WORK TO OVERCOME THIS CAP. THE
06Z/12Z NAM RUNS BOTH MANAGE TO DO SO...POPPING A STORM IN NE
LOWER BY EARLY EVENING. IT MANAGES THIS WHERE CONVERGENCE IS
MAXIMIZED (NE MONTMORENCY)...WHERE THE TWO DIFFERENT ORIENTATIONS
OF THE LAKE HURON LAKE BREEZE INTERSECT AND MEET THE BACKGROUND
SYNOPTIC SW WIND. AN 84/60 SURFACE PARCEL SURFACE PARCEL GENERATES
ABOUT 800J/KG OF SBCAPE (AND DOES GET PAST THE CAP)...BUT MLCAPE
IS STILL NEGLIGIBLE. AM A TOUCH MORE NERVOUS ABOUT A DRY FORECAST
TODAY THAN YESTERDAY...BUT AT THIS POINT STILL BELIEVE DRY IS THE
WAY TO GO. (NOTE THE SPC HRRR KEEPS US DRY.)
A FAIRLY VIGOROUS CU FIELD WILL BUBBLE UP AWAY FROM THE GREAT
LAKES AFTER MIDDAY...IN PARTICULAR NE LOWER AND NW CHIPPEWA CO.
THAT WILL CERTAINLY NOT PREVENT A WARM AFTERNOON...WITH HIGHS
FROM NEAR 80F TO THE MID 80S.
&&
.NEAR TERM...(TODAY THROUGH TONIGHT)
ISSUED AT 346 AM EDT SAT JUL 11 2015
...TURNING UP THE HEAT JUST A LITTLE MORE...
HIGH IMPACT WEATHER POTENTIAL: NONE.
OVERVIEW: SUBTROPICAL UPPER LEVEL RIDGE CONTINUES TO BUILD ACROSS
THE SRN GULF STATES...DOWNSTREAM OF TROUGHINESS ACROSS THE WESTERN
CONUS. IN BETWEEN...A FAIR AMOUNT OF HEAT/HUMIDITY IS STREAMING
FROM MEXICO UP THROUGH THE PLAINS AND ALONG THE FRONT RANGE OF THE
ROCKIES THEN BACK INTO THE PAC NW...WHERE SEVERAL SHOWER/
THUNDERSTORM COMPLEXES ARE ONGOING. FURTHER EAST...HIGH PRESSURE
REMAINS IN CONTROL FOR MUCH OF THE EASTERN CONUS...ALTHOUGH A FEW
ROUNDS OF SHOWERS ARE ONGOING IN THE MIDWEST AND MID ATLANTIC
STATES ALONG SOME SEMBLANCE OF A STALLED FRONT ACROSS THAT
REGION. BUT ONCE AGAIN A QUIET AND MILD NIGHT ACROSS THE GREAT
LAKES.
PATTERN FORECAST: SUBTROPICAL RIDGE WILL CONTINUE TO BUILD
WESTWARD TO BE CENTERED OVER TEXAS BY SUNDAY...AND RIDGE AXIS
STRETCHING UP INTO THE UPPER MIDWEST. BUT THIS DOES SHIFT AXIS OF
HEAT/HUMIDITY INTO THE PLAINS AND MIDWEST AND SETS UP A PROVERBIAL
"RING OF FIRE" AND POTENTIAL FOR ONE OR MORE SHOWER/THUNDERSTORM
COMPLEXES TO IMPACT THE REGION. MAIN FORECAST CONCERN IN THE
SHORTER TERM IS WHETHER OR NOT NRN MICHIGAN CAN "CATCH" ANY PRECIP
FROM ONE OF THESE SYSTEMS. SHORT ANSWER IS...PROBABLY NOT.
TODAY...NO WORRIES AS SFC HIGH PRESSURE REMAINS THE DOMINATE
PLAYER. TAKE YESTERDAYS HIGH TEMPS AND TAG ON ANOTHER FEW DEGREES
AS WARMER AIR INCHES IT/S WAY OUT OF THE PLAINS INTO THE WESTERN
GREAT LAKES EDGING H8 TEMPS ACROSS NRN MICHIGAN INTO THE 15C TO
16C RANGE BY EVENING. THIS SUGGESTS LOW TO MID 80S FOR MUCH OF THE
CWA. BUT PER FORECAST SOUNDINGS WE WILL ALSO SEE ANOTHER ROUND OF
SCT-BKN AFTERNOON CU SIMILAR TO YESTERDAY. CERTAINLY NOT OUT OF
THE QUESTION THAT WE COULD POP A FEW SHOWERS ACROSS NE LOWER
MICHIGAN WHERE LOW LEVEL CONVERGENCE WILL BE GREATEST (AND AS
SUGGESTED BY THE 00Z NAM BUT WHICH AGAIN IS OVERDOING SFC
DEWPOINTS/INSTABILITY). BUT LIKE YESTERDAY...WILL NOT BE ADDING
ANY POPS TO THE FORECAST AT THIS POINT.
TONIGHT...FORECAST CONFIDENCE BEGINS TO DWINDLE AS SUBTROPICAL
RIDGE CONTINUES TO SHIFT TO OVER TEXAS...FORCING HEAT/MOISTURE
AXIS TOWARD THE MIDWEST. NO DOUBT THERE WILL BE ADDITIONAL
SHOWER/THUNDERSTORM DEVELOPMENT TODAY FROM THE CENTRAL AND NRN
PLAINS INTO THE MIDWEST. QUESTION IS WHETHER ANY OF THAT CAN SNEAK
INTO NRN MICHIGAN. AGAIN SHORT ANSWER IS PROBABLY NOT. ALL
GUIDANCE KEEPS AXIS OF BEST MOISTURE/INSTABILITY ACROSS THE
MIDWEST WHICH IS WHERE CONTINUED FOCUS FOR SHOWERS/STORMS WILL
RESIDE THROUGH TONIGHT. AND IN THE ABSENCE OF ANY DECENT SYNOPTIC
FORCING TO DRAG SOMETHING THIS FAR NORTH...I JUST DON/T SEE IT.
HENCE HAVE REMOVED POPS FROM TONIGHTS FORECAST.
&&
.SHORT TERM...(SUNDAY THROUGH MONDAY NIGHT)
ISSUED AT 346 AM EDT SAT JUL 11 2015
HIGH IMPACT WEATHER: NONE
FORECAST CHALLENGE: DETERMINING WHEN SHOWERS AND THUNDERSTORMS WILL
BE MOST LIKELY.
(7/12)SUNDAY...THE FORECAST WAS TOUGH TO DETERMINE AS THE TWO MODELS
WERE AT ODDS WITH THE TIMING. HOWEVER, FOR THE SECOND NIGHT IN A
ROW, THE ECMWF HAS MANAGED TO PLAY CATCH UP TO THE GFS IDEA. SO HAVE
STARTED TO LEAN MORE TO THE GFS IDEAS WITH THE CONVECTION. LOOKING
AT THE SFC BASED CAPES OVER THE REGION THE LATE MORNING AND
AFTERNOON HAVE AROUND 1000J/KG ON ONE MODEL AND NEARLY 2000J/KG ON
THE OTHER. COUPLED WITH THE 500MB SHORTWAVE AND THE DEVELOPING SFC
WAVE, WILL PUT THE CHANCE OF THUNDERSTORMS IN THE REGION AS IT LOOKS
TO BE SCATTERED. OVERNIGHT DOESN`T LOOK AT GOOD, BUT THERE IS SOME
POTENTIAL AS THE INSTABILITY STILL LOOKS OKAY. THE ONE DOWNSIDE TO
ALL OF THIS CONVECTION IN THE MODELS IS THAT THE DEWPOINTS OVER THE
UPPER GREAT LAKES HAVE BEEN SIGNIFICANTLY LOWER THAN FORECAST IN THE
RAW MODELS, SO THIS INSTABILITY MAY BE A FIGMENT OF THE MODELS
IMAGINATION.
(7/13)MONDAY...WILL CONTINUE TO KEEP THE POPS TO A MINIMUM AS THE
DEWPOINTS ON THE MODELS ENDS UP IN THE LOWER 70S. THIS IS RARELY THE
CASE IN N MICHIGAN. SO WHILE THERE MAY BE SOME THUNDER, IT IS MORE
LIKELY THAT THERE WILL BE SCATTERED SHOWERS. WILL SEE HOW THIS WORKS
OUT, BUT FOR NOW WILL KEEP THE FORECAST ON THE LOWER CHANCE SIDE.
THIS FORECAST MAY BE A LITTLE TOO WET, BASED ON WHAT WE HAVE SEEN
FOR THE YEAR SO FAR.
&&
.LONG TERM...(TUESDAY THROUGH FRIDAY)
ISSUED AT 346 AM EDT SAT JUL 11 2015
EXTENDED (TUESDAY THROUGH FRIDAY)...THERE ARE TIMING DIFFERENCES
BETWEEN THE MODELS ON TUESDAY, WITH THE GFS PUSHING THE DRY AIR INTO
THE UPPER GREAT LAKES SOONER THAN THE ECMWF (TUESDAY NIGHT).
HOWEVER, THE BASIC IDEA IS THE SAME, WITH THE SERIES OF WAVES THAT
MOVE THROUGH THE FLOW AND BRING CHANCES OF SHOWERS AND THUNDERSTORMS
EVERY OTHER DAY OR TWO. TEMPERATURES LOOK TO REMAIN AROUND NORMAL
FOR THIS TIME OF YEAR THROUGH THE END OF THE WEEK.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON)
ISSUED AT 133 PM EDT SAT JUL 11 2015
VFR.
LITTLE CHANGE THRU TONIGHT...WITH HIGH PRESSURE PARKED IN THE
SOUTHERN GREAT LAKES. CU FIELD WILL LAST THRU THE AFTERNOON...THEN
DIMINISH THIS EVENING. WE WILL SEE SOME HIGH CLOUDS
TONIGHT...ESPECIALLY IN NW LOWER. THAT RAMPS UP TO THE POTENTIAL
FOR A FEW SHRA TOMORROW...BUT MAINLY LATER IN THE DAY.
LIGHT SW SURFACE WINDS WILL GIVE WAY TO LAKE BREEZES THIS
AFTERNOON. LIGHT WINDS TONIGHT/SUNDAY MORNING.
&&
.MARINE...
ISSUED AT 346 AM EDT SAT JUL 11 2015
OVERALL LARGE SCALE SW-S FLOW DEVELOPS ACROSS THE WESTERN GREAT
LAKES TODAY AND TONIGHT...ALTHOUGH WINDS CLOSER TO SHORE WILL BE
ONCE AGAIN HEAVILY INFLUENCED BY LAKE BREEZES THIS AFTERNOON. BUT
WIND SPEEDS SHOULD REMAIN 10 KNOTS OR LESS ACROSS THE REGION. A
SIMILAR STORY FOR SUNDAY AND SUNDAY ALTHOUGH WINDS MAY INCREASE
JUST A BIT MORE HEADING INTO SUNDAY NIGHT AS LOW PRESSURE MOVES
TOWARD THE UPPER MIDWEST. BUT NO MARINE HEADLINES ARE ANTICIPATED
THROUGH THE WEEKEND.
&&
.APX WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LH...NONE.
LM...NONE.
LS...NONE.
&&
$$
UPDATE...JAZ
NEAR TERM...ADAM
SHORT TERM...JSL
LONG TERM...JSL
AVIATION...JAZ
MARINE...ADAM
AREA FORECAST DISCUSSION
NWS GAYLORD MI
1018 AM EDT SAT JUL 11 2015
.UPDATE...
ISSUED AT 1018 AM EDT SAT JUL 11 2015
ANOTHER IDEAL MORNING IN NORTHERN MI. SKIES ARE JUST ABOUT
CLEAR...WITH SOME HIGH-BASED CU IN THE GD TRAV BAY REGION...AND
IN PARTS OF CENTRAL UPPER MI. THIS IS ASSOCIATED WITH A SUBTLE
WARM FRONT ADVANCING EAST NEAR MUNISING/ISQ...AND IS OCCURRING IN
THE STEEP LAPSE RATES AT THE TOP OF YESTERDAYS MIXED LAYER. THERE
IS STRONG INVERSION PRESENT ABOVE THIS. PER 12Z OBSERVED
SOUNDINGS...700MB TEMPS ARE 9C AT APX...10C AT GRB. THIS IS NOT
SURPRISING...GIVEN A 500MB SHORTWAVE RIDGE AXIS WILL BE DEAD
OVERHEAD THIS AFTERNOON.
SO IT WILL TAKE SOME SERIOUS WORK TO OVERCOME THIS CAP. THE
06Z/12Z NAM RUNS BOTH MANAGE TO DO SO...POPPING A STORM IN NE
LOWER BY EARLY EVENING. IT MANAGES THIS WHERE CONVERGENCE IS
MAXIMIZED (NE MONTMORENCY)...WHERE THE TWO DIFFERENT ORIENTATIONS
OF THE LAKE HURON LAKE BREEZE INTERSECT AND MEET THE BACKGROUND
SYNOPTIC SW WIND. AN 84/60 SURFACE PARCEL SURFACE PARCEL GENERATES
ABOUT 800J/KG OF SBCAPE (AND DOES GET PAST THE CAP)...BUT MLCAPE
IS STILL NEGLIGIBLE. AM A TOUCH MORE NERVOUS ABOUT A DRY FORECAST
TODAY THAN YESTERDAY...BUT AT THIS POINT STILL BELIEVE DRY IS THE
WAY TO GO. (NOTE THE SPC HRRR KEEPS US DRY.)
A FAIRLY VIGOROUS CU FIELD WILL BUBBLE UP AWAY FROM THE GREAT
LAKES AFTER MIDDAY...IN PARTICULAR NE LOWER AND NW CHIPPEWA CO.
THAT WILL CERTAINLY NOT PREVENT A WARM AFTERNOON...WITH HIGHS
FROM NEAR 80F TO THE MID 80S.
&&
.NEAR TERM...(TODAY THROUGH TONIGHT)
ISSUED AT 346 AM EDT SAT JUL 11 2015
...TURNING UP THE HEAT JUST A LITTLE MORE...
HIGH IMPACT WEATHER POTENTIAL: NONE.
OVERVIEW: SUBTROPICAL UPPER LEVEL RIDGE CONTINUES TO BUILD ACROSS
THE SRN GULF STATES...DOWNSTREAM OF TROUGHINESS ACROSS THE WESTERN
CONUS. IN BETWEEN...A FAIR AMOUNT OF HEAT/HUMIDITY IS STREAMING
FROM MEXICO UP THROUGH THE PLAINS AND ALONG THE FRONT RANGE OF THE
ROCKIES THEN BACK INTO THE PAC NW...WHERE SEVERAL SHOWER/
THUNDERSTORM COMPLEXES ARE ONGOING. FURTHER EAST...HIGH PRESSURE
REMAINS IN CONTROL FOR MUCH OF THE EASTERN CONUS...ALTHOUGH A FEW
ROUNDS OF SHOWERS ARE ONGOING IN THE MIDWEST AND MID ATLANTIC
STATES ALONG SOME SEMBLANCE OF A STALLED FRONT ACROSS THAT
REGION. BUT ONCE AGAIN A QUIET AND MILD NIGHT ACROSS THE GREAT
LAKES.
PATTERN FORECAST: SUBTROPICAL RIDGE WILL CONTINUE TO BUILD
WESTWARD TO BE CENTERED OVER TEXAS BY SUNDAY...AND RIDGE AXIS
STRETCHING UP INTO THE UPPER MIDWEST. BUT THIS DOES SHIFT AXIS OF
HEAT/HUMIDITY INTO THE PLAINS AND MIDWEST AND SETS UP A PROVERBIAL
"RING OF FIRE" AND POTENTIAL FOR ONE OR MORE SHOWER/THUNDERSTORM
COMPLEXES TO IMPACT THE REGION. MAIN FORECAST CONCERN IN THE
SHORTER TERM IS WHETHER OR NOT NRN MICHIGAN CAN "CATCH" ANY PRECIP
FROM ONE OF THESE SYSTEMS. SHORT ANSWER IS...PROBABLY NOT.
TODAY...NO WORRIES AS SFC HIGH PRESSURE REMAINS THE DOMINATE
PLAYER. TAKE YESTERDAYS HIGH TEMPS AND TAG ON ANOTHER FEW DEGREES
AS WARMER AIR INCHES IT/S WAY OUT OF THE PLAINS INTO THE WESTERN
GREAT LAKES EDGING H8 TEMPS ACROSS NRN MICHIGAN INTO THE 15C TO
16C RANGE BY EVENING. THIS SUGGESTS LOW TO MID 80S FOR MUCH OF THE
CWA. BUT PER FORECAST SOUNDINGS WE WILL ALSO SEE ANOTHER ROUND OF
SCT-BKN AFTERNOON CU SIMILAR TO YESTERDAY. CERTAINLY NOT OUT OF
THE QUESTION THAT WE COULD POP A FEW SHOWERS ACROSS NE LOWER
MICHIGAN WHERE LOW LEVEL CONVERGENCE WILL BE GREATEST (AND AS
SUGGESTED BY THE 00Z NAM BUT WHICH AGAIN IS OVERDOING SFC
DEWPOINTS/INSTABILITY). BUT LIKE YESTERDAY...WILL NOT BE ADDING
ANY POPS TO THE FORECAST AT THIS POINT.
TONIGHT...FORECAST CONFIDENCE BEGINS TO DWINDLE AS SUBTROPICAL
RIDGE CONTINUES TO SHIFT TO OVER TEXAS...FORCING HEAT/MOISTURE
AXIS TOWARD THE MIDWEST. NO DOUBT THERE WILL BE ADDITIONAL
SHOWER/THUNDERSTORM DEVELOPMENT TODAY FROM THE CENTRAL AND NRN
PLAINS INTO THE MIDWEST. QUESTION IS WHETHER ANY OF THAT CAN SNEAK
INTO NRN MICHIGAN. AGAIN SHORT ANSWER IS PROBABLY NOT. ALL
GUIDANCE KEEPS AXIS OF BEST MOISTURE/INSTABILITY ACROSS THE
MIDWEST WHICH IS WHERE CONTINUED FOCUS FOR SHOWERS/STORMS WILL
RESIDE THROUGH TONIGHT. AND IN THE ABSENCE OF ANY DECENT SYNOPTIC
FORCING TO DRAG SOMETHING THIS FAR NORTH...I JUST DON/T SEE IT.
HENCE HAVE REMOVED POPS FROM TONIGHTS FORECAST.
&&
.SHORT TERM...(SUNDAY THROUGH MONDAY NIGHT)
ISSUED AT 346 AM EDT SAT JUL 11 2015
HIGH IMPACT WEATHER: NONE
FORECAST CHALLENGE: DETERMINING WHEN SHOWERS AND THUNDERSTORMS WILL
BE MOST LIKELY.
(7/12)SUNDAY...THE FORECAST WAS TOUGH TO DETERMINE AS THE TWO MODELS
WERE AT ODDS WITH THE TIMING. HOWEVER, FOR THE SECOND NIGHT IN A
ROW, THE ECMWF HAS MANAGED TO PLAY CATCH UP TO THE GFS IDEA. SO HAVE
STARTED TO LEAN MORE TO THE GFS IDEAS WITH THE CONVECTION. LOOKING
AT THE SFC BASED CAPES OVER THE REGION THE LATE MORNING AND
AFTERNOON HAVE AROUND 1000J/KG ON ONE MODEL AND NEARLY 2000J/KG ON
THE OTHER. COUPLED WITH THE 500MB SHORTWAVE AND THE DEVELOPING SFC
WAVE, WILL PUT THE CHANCE OF THUNDERSTORMS IN THE REGION AS IT LOOKS
TO BE SCATTERED. OVERNIGHT DOESN`T LOOK AT GOOD, BUT THERE IS SOME
POTENTIAL AS THE INSTABILITY STILL LOOKS OKAY. THE ONE DOWNSIDE TO
ALL OF THIS CONVECTION IN THE MODELS IS THAT THE DEWPOINTS OVER THE
UPPER GREAT LAKES HAVE BEEN SIGNIFICANTLY LOWER THAN FORECAST IN THE
RAW MODELS, SO THIS INSTABILITY MAY BE A FIGMENT OF THE MODELS
IMAGINATION.
(7/13)MONDAY...WILL CONTINUE TO KEEP THE POPS TO A MINIMUM AS THE
DEWPOINTS ON THE MODELS ENDS UP IN THE LOWER 70S. THIS IS RARELY THE
CASE IN N MICHIGAN. SO WHILE THERE MAY BE SOME THUNDER, IT IS MORE
LIKELY THAT THERE WILL BE SCATTERED SHOWERS. WILL SEE HOW THIS WORKS
OUT, BUT FOR NOW WILL KEEP THE FORECAST ON THE LOWER CHANCE SIDE.
THIS FORECAST MAY BE A LITTLE TOO WET, BASED ON WHAT WE HAVE SEEN
FOR THE YEAR SO FAR.
&&
.LONG TERM...(TUESDAY THROUGH FRIDAY)
ISSUED AT 346 AM EDT SAT JUL 11 2015
EXTENDED (TUESDAY THROUGH FRIDAY)...THERE ARE TIMING DIFFERENCES
BETWEEN THE MODELS ON TUESDAY, WITH THE GFS PUSHING THE DRY AIR INTO
THE UPPER GREAT LAKES SOONER THAN THE ECMWF (TUESDAY NIGHT).
HOWEVER, THE BASIC IDEA IS THE SAME, WITH THE SERIES OF WAVES THAT
MOVE THROUGH THE FLOW AND BRING CHANCES OF SHOWERS AND THUNDERSTORMS
EVERY OTHER DAY OR TWO. TEMPERATURES LOOK TO REMAIN AROUND NORMAL
FOR THIS TIME OF YEAR THROUGH THE END OF THE WEEK.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SUNDAY MORNING)
ISSUED AT 646 AM EDT SAT JUL 11 2015
VFR CONDITIONS ARE SET TO CONTINUE TODAY AND TONIGHT WITH JUST A
GRADUAL ARRIVAL AND LOWERING OF THICKER CIRRUS THROUGH THE TAF
PERIOD. WILL ALSO SEE SCT-BKN CU DEVELOPMENT ACROSS NRN LOWER
MICHIGAN AGAIN FOR THIS AFTERNOON...AND MAINLY IMPACTING THE APN
TERMINAL SITE.
WINDS...LIGHT EARLY THIS MORNING THEN TURNING MAINLY SOUTHWEST
AROUND 10 KNOTS TODAY...THOUGH INFLUENCED BY LAKE BREEZE
DEVELOPMENT PARTICULARLY AROUND KAPN.
&&
.MARINE...
ISSUED AT 346 AM EDT SAT JUL 11 2015
OVERALL LARGE SCALE SW-S FLOW DEVELOPS ACROSS THE WESTERN GREAT
LAKES TODAY AND TONIGHT...ALTHOUGH WINDS CLOSER TO SHORE WILL BE
ONCE AGAIN HEAVILY INFLUENCED BY LAKE BREEZES THIS AFTERNOON. BUT
WIND SPEEDS SHOULD REMAIN 10 KNOTS OR LESS ACROSS THE REGION. A
SIMILAR STORY FOR SUNDAY AND SUNDAY ALTHOUGH WINDS MAY INCREASE
JUST A BIT MORE HEADING INTO SUNDAY NIGHT AS LOW PRESSURE MOVES
TOWARD THE UPPER MIDWEST. BUT NO MARINE HEADLINES ARE ANTICIPATED
THROUGH THE WEEKEND.
&&
.APX WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LH...NONE.
LM...NONE.
LS...NONE.
&&
$$
UPDATE...JAZ
NEAR TERM...ADAM
SHORT TERM...JSL
LONG TERM...JSL
AVIATION...ADAM
MARINE...ADAM
AREA FORECAST DISCUSSION
NWS DULUTH MN
702 PM CDT SUN JUL 12 2015
.UPDATE...
ISSUED AT 555 PM CDT SUN JUL 12 2015
UPDATED TO ADD TORNADO WATCH. LOW LEVEL SHEAR HAS BEEN INCREASING
IN THE WATCH AREA. HAVE BEEN WATCHING TORNADIC STORMS TO THE WEST
AND EXPECT THIS SYSTEM TO EVENTUALLY SPREAD INTO EATCH AREA IN THE
NEXT HOUR OR SO AS DESTABILIZATION INCREASES. LOOKS LIKE EARLIER
CIN IS GONE...SO WILL SEE A RAPID INCREASE IN STORM STREGTH.
GOOD-LOOKING HODOGRAPH FOR BRAINERD SUGGEST STRONG POTENTIAL FOR
ROTATING STORMS WITH LARGE HAIL DAMAGING WINDS AND TORNADOES.
&&
.SHORT TERM...(THIS EVENING THROUGH MONDAY)
ISSUED AT 333 PM CDT SUN JUL 12 2015
THE FORECAST AREA WAS BETWEEN DEPARTING HIGH PRESSURE OVER NORTHERN
LAKE SUPERIOR AND LOW PRESSURE MOVING THROUGH SE ND. A WARM FRONT
EXTENDED SEWD FROM THE LOW THROUGH WEST CENTRAL AND SW MN. THE LAST
REMNANTS OF THE MORNING THUNDERSTORMS WAS OVER THE TIP OF THE
ARROWHEAD AND SHOULD EXIT BY 21Z. NEW SHOWERS AND STORMS WERE
DEVELOPING IN WEST CENTRAL MN N OF THE WARM FRONT AND A COUPLE
COUNTIES W OF THE AREA. SOME OF THE CLOUDS HAVE DISSIPATED ALLOWING
FOR SOME WARMING AND AN INCREASE IN DEWPOINTS AS WELL AS AN INCREASE
IN INSTABILITY. EXPECT THUNDERSTORMS TO FORM ALONG AND N OF THE WARM
FRONT THROUGH THE REST OF THE AFTERNOON AND GRADUALLY SPREAD INTO
THE WESTERN PORTION OF THE REGION.
EXPECT SOME OF THE STORMS TO BECOME SEVERE TONIGHT AND PERCOLATE IN
THE VCNTY OF THE FORECAST AREA UNTIL 06Z. LATEST HRRR IS IN
AGREEMENT WITH THIS ASSESSMENT. SOME STORMS WILL STILL BE AROUND
THROUGH THE OVERNIGHT WITH HEAVY RAIN ACCOMPANYING SOME OF THE
STRONGER STORMS. HAVE SHOWN A GRADUAL DECREASE IN POPS AFTER 08Z
THROUGH 12Z AS HIGH PRESSURE BEGINS TO BUILD INTO THE AREA. EVEN
THOUGH SOME NICE RAIN WAS NOTED DURING THE DAY...NOT EXPECTING ANY
FLOODING ISSUES WITH THE STORMS TONIGHT.
ON MONDAY...THE SFC LOW MOVES ACROSS CENTRAL MN INTO NORTHERN WI.
SOME AREAS WILL GET A BREAK FROM THE STORMS IN THE MORNING BEFORE
REDEVELOPMENT BEGINS BY AFTERNOON. SOME OF THE STORMS MAY CONTAIN
BRIEF MODERATE DOWNPOURS. THE MAJORITY OF THE RAIN WILL FALL ALONG
AND N OF THE LOW TRACK WHERE AN UPPER LEVEL SHORT WAVE WILL TRACK
THROUGH THE AREA AS WELL.
.LONG TERM...(MONDAY NIGHT THROUGH SUNDAY)
ISSUED AT 333 PM CDT SUN JUL 12 2015
ACTIVE WEATHER PATTERN STILL LOOKS LIKELY WITH CHANCES FOR SHOWERS
AND STORMS MOST DAYS THIS WEEK. TEMPERATURES WILL BRIEFLY COOL DOWN
TO MORE SEASONABLE TEMPS MID-WEEK...RETURNING TO THE UNSEASONABLY
WARM AND HUMID WEATHER BY THE WEEKEND.
ON THE SYNOPTIC SCALE THE INFLUENCE OF THE 500MB RIDGE/UPPER HIGH
OVER THE SOUTHERN PLAINS WILL GIVE WAY TO A SERIES OF MID-LEVEL
DISTURBANCES THAT WILL MOVE ACROSS THE NORTHERN TIER OF THE COUNTRY.
A DEEP LONGWAVE TROUGH OVER THE WEST COAST WILL BEGIN TO FLATTEN OUT
AND CAUSE A SERIES OF MID-LEVEL SHORTWAVES TO MOVE EAST OVER THE
RIDGE. ON MONDAY NIGHT INTO TUESDAY A DEPARTING SFC LOW WILL GIVE
WAY TO A COLD FRONT MOVING IN FROM THE NORTH ON LATE TUESDAY. THIS
FRONTAL PASSAGE WILL RESULT IN NORTH TO NORTHEASTERLY WINDS AT LOW
LEVELS AND THUS COOLER TEMPS. THE COMBINATION OF THE ORIGIN OF THIS
AIR /CANADA/ AND THE FACT THAT MOST OF IT IS MOVING OVER LAKE
SUPERIOR BEFORE REACHING LAND WILL RESULT IN MUCH COOLER AND DRIER
/LOWER DEW POINT/ AIR. HOWEVER...WITH A RIDGE AXIS ALOFT MOVING
ACROSS THE AREA EARLY WEDNESDAY SOUTHWESTERLY FLOW WILL RETURN
RESULTING IN RISING TEMPS AND DEW POINT VALUES.
LATE IN THE WEEK WE HAVE FAIRLY HIGH PRECIP CHANCES...THOUGH THE
EXACT DETAILS OF EACH DAY ARE STILL TOUGH TO PIN DOWN.
REGARDLESS...OVERALL PATTERN IS FAVORABLE FOR SHOWERS AND STORMS
EACH DAY. LATE IN THE WEEK INTO THE WEEKEND GUIDANCE IS DEPICTING
MUCH STRONGER WINDS ALOFT WITH A 120KT OR SO JET AT 250MB. THESE
STRONGER WINDS ALOFT COULD LEAD TO A BETTER ENVIRONMENT THUNDERSTORM
DEVELOPMENT...DEPENDING ON HOW MUCH INSTABILITY CAN DEVELOP. WILL
DEFINITELY BE SOMETHING TO WATCH AS IT HAS BEEN A WHILE SINCE WE
HAVE HAD STRONGER WINDS ALOFT.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z MONDAY EVENING)
ISSUED AT 656 PM CDT SUN JUL 12 2015
THUNDERSTORMS WILL BECOME NUMEROUS OVER MUCH OF THE FORECAST AREA
THIS EVENING...THORUGH 06Z. THERE IS A CHANCE OF SVR STORMS WITH
HAIL...HIGH WINDS AND TORNADOES IN THE BRAINERD AREA. LATER
TONIGHT AFTER 06Z SOME AREAS WILL HAVE FOG 1-3SM...THEN CLEARING
AFTER 12Z. MORE STORMS ARE LIKELY AFT 18Z MONDAY.
&&
.PRELIMINARY POINT TEMPS/POPS...
DLH 64 80 64 71 / 60 40 30 40
INL 61 83 62 78 / 70 40 30 40
BRD 63 85 64 82 / 50 50 40 50
HYR 64 82 63 76 / 60 50 30 30
ASX 61 80 60 69 / 60 40 30 40
&&
.DLH WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
LS...NONE.
&&
$$
UPDATE...CLC
SHORT TERM...GSF
LONG TERM...JJM
AVIATION...CLC
AREA FORECAST DISCUSSION...UPDATED
NWS DULUTH MN
603 PM CDT SUN JUL 12 2015
.UPDATE...
ISSUED AT 555 PM CDT SUN JUL 12 2015
UPDATED TO ADD TORNADO WATCH. LOW LEVEL SHEAR HAS BEEN INCREASING
IN THE WATCH AREA. HAVE BEEN WATCHING TORNADIC STORMS TO THE WEST
AND EXPECT THIS SYSTEM TO EVENTUALLY SPREAD INTO EATCH AREA IN THE
NEXT HOUR OR SO AS DESTABILIZATION INCREASES. LOOKS LIKE EARLIER
CIN IS GONE...SO WILL SEE A RAPID INCREASE IN STORM STREGTH.
GOOD-LOOKING HODOGRAPH FOR BRAINERD SUGGEST STRONG POTENTIAL FOR
ROTATING STORMS WITH LARGE HAIL DAMAGING WINDS AND TORNADOES.
&&
.SHORT TERM...(THIS EVENING THROUGH MONDAY)
ISSUED AT 333 PM CDT SUN JUL 12 2015
THE FORECAST AREA WAS BETWEEN DEPARTING HIGH PRESSURE OVER NORTHERN
LAKE SUPERIOR AND LOW PRESSURE MOVING THROUGH SE ND. A WARM FRONT
EXTENDED SEWD FROM THE LOW THROUGH WEST CENTRAL AND SW MN. THE LAST
REMNANTS OF THE MORNING THUNDERSTORMS WAS OVER THE TIP OF THE
ARROWHEAD AND SHOULD EXIT BY 21Z. NEW SHOWERS AND STORMS WERE
DEVELOPING IN WEST CENTRAL MN N OF THE WARM FRONT AND A COUPLE
COUNTIES W OF THE AREA. SOME OF THE CLOUDS HAVE DISSIPATED ALLOWING
FOR SOME WARMING AND AN INCREASE IN DEWPOINTS AS WELL AS AN INCREASE
IN INSTABILITY. EXPECT THUNDERSTORMS TO FORM ALONG AND N OF THE WARM
FRONT THROUGH THE REST OF THE AFTERNOON AND GRADUALLY SPREAD INTO
THE WESTERN PORTION OF THE REGION.
EXPECT SOME OF THE STORMS TO BECOME SEVERE TONIGHT AND PERCOLATE IN
THE VCNTY OF THE FORECAST AREA UNTIL 06Z. LATEST HRRR IS IN
AGREEMENT WITH THIS ASSESSMENT. SOME STORMS WILL STILL BE AROUND
THROUGH THE OVERNIGHT WITH HEAVY RAIN ACCOMPANYING SOME OF THE
STRONGER STORMS. HAVE SHOWN A GRADUAL DECREASE IN POPS AFTER 08Z
THROUGH 12Z AS HIGH PRESSURE BEGINS TO BUILD INTO THE AREA. EVEN
THOUGH SOME NICE RAIN WAS NOTED DURING THE DAY...NOT EXPECTING ANY
FLOODING ISSUES WITH THE STORMS TONIGHT.
ON MONDAY...THE SFC LOW MOVES ACROSS CENTRAL MN INTO NORTHERN WI.
SOME AREAS WILL GET A BREAK FROM THE STORMS IN THE MORNING BEFORE
REDEVELOPMENT BEGINS BY AFTERNOON. SOME OF THE STORMS MAY CONTAIN
BRIEF MODERATE DOWNPOURS. THE MAJORITY OF THE RAIN WILL FALL ALONG
AND N OF THE LOW TRACK WHERE AN UPPER LEVEL SHORT WAVE WILL TRACK
THROUGH THE AREA AS WELL.
.LONG TERM...(MONDAY NIGHT THROUGH SUNDAY)
ISSUED AT 333 PM CDT SUN JUL 12 2015
ACTIVE WEATHER PATTERN STILL LOOKS LIKELY WITH CHANCES FOR SHOWERS
AND STORMS MOST DAYS THIS WEEK. TEMPERATURES WILL BRIEFLY COOL DOWN
TO MORE SEASONABLE TEMPS MID-WEEK...RETURNING TO THE UNSEASONABLY
WARM AND HUMID WEATHER BY THE WEEKEND.
ON THE SYNOPTIC SCALE THE INFLUENCE OF THE 500MB RIDGE/UPPER HIGH
OVER THE SOUTHERN PLAINS WILL GIVE WAY TO A SERIES OF MID-LEVEL
DISTURBANCES THAT WILL MOVE ACROSS THE NORTHERN TIER OF THE COUNTRY.
A DEEP LONGWAVE TROUGH OVER THE WEST COAST WILL BEGIN TO FLATTEN OUT
AND CAUSE A SERIES OF MID-LEVEL SHORTWAVES TO MOVE EAST OVER THE
RIDGE. ON MONDAY NIGHT INTO TUESDAY A DEPARTING SFC LOW WILL GIVE
WAY TO A COLD FRONT MOVING IN FROM THE NORTH ON LATE TUESDAY. THIS
FRONTAL PASSAGE WILL RESULT IN NORTH TO NORTHEASTERLY WINDS AT LOW
LEVELS AND THUS COOLER TEMPS. THE COMBINATION OF THE ORIGIN OF THIS
AIR /CANADA/ AND THE FACT THAT MOST OF IT IS MOVING OVER LAKE
SUPERIOR BEFORE REACHING LAND WILL RESULT IN MUCH COOLER AND DRIER
/LOWER DEW POINT/ AIR. HOWEVER...WITH A RIDGE AXIS ALOFT MOVING
ACROSS THE AREA EARLY WEDNESDAY SOUTHWESTERLY FLOW WILL RETURN
RESULTING IN RISING TEMPS AND DEW POINT VALUES.
LATE IN THE WEEK WE HAVE FAIRLY HIGH PRECIP CHANCES...THOUGH THE
EXACT DETAILS OF EACH DAY ARE STILL TOUGH TO PIN DOWN.
REGARDLESS...OVERALL PATTERN IS FAVORABLE FOR SHOWERS AND STORMS
EACH DAY. LATE IN THE WEEK INTO THE WEEKEND GUIDANCE IS DEPICTING
MUCH STRONGER WINDS ALOFT WITH A 120KT OR SO JET AT 250MB. THESE
STRONGER WINDS ALOFT COULD LEAD TO A BETTER ENVIRONMENT THUNDERSTORM
DEVELOPMENT...DEPENDING ON HOW MUCH INSTABILITY CAN DEVELOP. WILL
DEFINITELY BE SOMETHING TO WATCH AS IT HAS BEEN A WHILE SINCE WE
HAVE HAD STRONGER WINDS ALOFT.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON)
ISSUED AT 1246 PM CDT SUN JUL 12 2015
MORNING CONVECTION ENDED UP BEING A BIT MORE WIDESPREAD THAN
ORIGINALLY EXPECTED...WHICH IS CAUSING SOME MVFR TO IFR CEILINGS
TO HANG AROUND A LITTLE LONGER THAN ANTICIPATED. HOWEVER...STILL
EXPECT SOME CLEARING AND IMPROVEMENT TO VFR AT A FEW SITES THIS
AFTERNOON. ANOTHER ROUND OF STORMS WILL MOVE THROUGH THE REGION
TONIGHT BETWEEN 00Z AND 06Z. THESE STORMS ARE EXPECTED TO BE
STRONG TO SEVERE AND FAST MOVING...PRODUCING HEAVY RAINFALL
REDUCING VISIBILITY TO IFR/LIFR FOR A BRIEF TIME. FOLLOWING THESE
STORMS EXPECT AT LEAST SOME PATCHY FOG AND STRATUS TO
DEVELOP...WITH IFR CONDITIONS GRADUALLY IMPROVING TO MVFR/VFR BY
LATE MONDAY MORNING.
&&
.PRELIMINARY POINT TEMPS/POPS...
DLH 64 80 64 71 / 60 40 30 40
INL 61 83 62 78 / 70 40 30 40
BRD 63 85 64 82 / 50 50 40 50
HYR 64 82 63 76 / 60 50 30 30
ASX 61 80 60 69 / 60 40 30 40
&&
.DLH WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
LS...NONE.
&&
$$
UPDATE...CLC
SHORT TERM...GSF
LONG TERM...JJM
AVIATION...JJM
AREA FORECAST DISCUSSION
NWS DULUTH MN
307 PM CDT SAT JUL 11 2015
.SHORT TERM...(THIS EVENING THROUGH SUNDAY)
ISSUED AT 307 PM CDT SAT JUL 11 2015
EVEN THOUGH THERE WAS A RIDGE OF HIGH PRESSURE OVER THE FORECAST AREA
AT 19Z...PLENTY OF CUMULUS HAD FORMED AND COVERED THE AREA. A LAKE
BREEZE WAS TRYING TO DEVELOP WITH A NE FLOW OFF LAKE SUPERIOR.
HOWEVER...LOW LEVEL WAA WAS KEEPING IT FROM PUSHING TOO FAR INLAND.
THE FEW SHOWERS THAT HAD FORMED EARLIER HAD DISSIPATED. 17Z HRRR RUN
CONTINUES TO DOWNPLAY ANY STORMS FROM DEVELOPING THIS EVENING. AFTER
06Z...MODELS POINT TOWARD AN AREA OF SHOWERS AND THUNDERSTORMS
INITIATING OVER THE SOUTHERN TIER OF THE REGION FROM THE BRAINERD
LAKES EAST TO THE ST. CROIX RIVER VALLEY. THIS WILL BE ON THE
LEADING EDGE OF A WARM FRONT INTERACTING WITH A WEAK SHORT WAVE
TROF. WITH THE WAA...THERE IS A POSSIBILITY THAT A CAPPING INVERSION
MAY KEEP STORMS FROM HAPPENING. MODEL QPF APPEARS TO BE OVERDONE AND
HAVE USED A BLEND OF MODELS FOR QPF AND HAVE POPS TO MATCH.
ON SUNDAY...UPPER LEVEL RIDGING BUILDS DURING THE DAY WHICH MAY
HAMPER THUNDERSTORMS. HOWEVER...STORMS MAY BE ONGOING EARLY IN THE
MORNING BEFORE DISSIPATING BY MID MORNING. HAVE SHOWN THIS TREND
WITH POPS. IN THE AFTERNOON...MODELS DISAGREE ON THE IMPACT OF A
WEAK SHORT WAVE MOVING OVER THE AREA. A CAPPING INVERSION IS
DEVELOPING IN THE AFTERNOON...BUT MODELS DISAGREE ON THE STRENGTH
AND PLACEMENT. REGARDLESS...HAVE LOW POPS ALIGNED OVER THE APEX OF
THE INVERSION EARLY IN THE AFTERNOON. THERE IS ALSO DISAGREEMENT IN
THE LATE AFTERNOON ON THE EVENTUAL BREAKDOWN OF THE INVERSION. USED
A CONSENSUS APPROACH TO POPS IN THE LATE AFTERNOON. HUMIDITY WILL BE
ON THE INCREASE SUNDAY WITH DEWPOINTS REACHING THE LOWER 70S IN
SEVERAL LOCATIONS.
.LONG TERM...(SUNDAY NIGHT THROUGH SATURDAY)
ISSUED AT 307 PM CDT SAT JUL 11 2015
A GENERALLY ACTIVE PATTERN COMING UP THIS WEEK WITH SEASONABLE
TEMPERATURES ON TAP. THE LONG TERM PERIOD BEGINS WITH THUNDERSTORMS
EXPECTED TO BE ONGOING SUNDAY NIGHT BEFORE A COLD FRONT MOVES
THROUGH MONDAY NIGHT. A MID-LEVEL SHORTWAVE RIDGE WILL MOVE ACROSS
THE REGION BY MID-WEEK WHICH MAY RESULT IN A BREAK IN THE STORMY
PATTERN...BUT THEN BY LATE WEEK THE MID/UPPER LEVEL PATTERNS TURNS
SOUTHWESTERLY WITH A NUMBER OF DISTURBANCES ACROSS THE UPPER
MIDWEST.
SUNDAY NIGHT...EXPECT ONGOING STORMS ACROSS THE REGION...WITH THE
BEST CHANCE FOR STORMS SOUTH OF HIGHWAY 2. GFS IS BY FAR THE MOST
AGGRESSIVE WITH QPF BOTH THIS NIGHT AND THROUGH THE ENTIRE FORECAST
PERIOD...THOUGH ALL GUIDANCE SUPPORTS FAIRLY GOOD INSTABILITY INTO
SUNDAY NIGHT WHICH SHOULD RESULT IN SCATTERED TO NUMEROUS
THUNDERSTORMS. A FEW COULD BE STRONG WITH 3000-4000 J/KG MUCAPE
AVAILABLE EARLY IN THE EVENING. OTHERWISE A MILD NIGHT WITH LOWS IN
THE LOW TO MID 60S.
MONDAY INTO MONDAY NIGHT...WHEN THE FRONT MOVES THROUGH EXPECT
ANOTHER ROUND OF SHOWERS AND STORMS...THOUGH INSTABILITY NOT AS
IMPRESSIVE AS SUNDAY NIGHT.
TUESDAY THROUGH FRIDAY...NOT AS WARM WITH CHANCES FOR SHOWERS AND
STORMS MOST DAYS...WITH THE BEST CHANCE THURSDAY INTO THURSDAY
NIGHT. HIGHS IN THE 70S...LOWS IN THE LOW TO MID 50S BY THE LAKE AND
UPPER 50S TO LOW 60S INLAND. AS COOLER AND DRIER AIR MOVES IN FROM
THE NORTHEAST DEW POINTS WILL FALL...RESULTING IN MUCH LESS HUMID
CONDITIONS FOR THE LATTER PORTIONS OF THE WEEK.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON)
ISSUED AT 1223 PM CDT SAT JUL 11 2015
VFR CONDITIONS EXPECTED TO PERSIST THROUGH MUCH OF THE
AFTERNOON...WITH MVFR TO IFR CEILINGS AND VISIBILITY POSSIBLE AT
ALL SITES OVERNIGHT TONIGHT. THIS AFTERNOON EXPECT WIDESPREAD VFR
CLOUDS WITH A FEW SHOWERS AND MAYBE A THUNDERSTORM OR TWO.
THIS EVENING...CHANCES FOR STORMS INCREASE...WITH BETTER CHANCES
AT BRD/DLH/HYR. THEN LATE TONIGHT /AFTER MIDNIGHT/ EXPECT PATCHY
FOG AND IFR CEILINGS TO DEVELOP...WITH A FEW SPOTS DEVELOPING LIFR
CEILINGS. WINDS THROUGH THE PERIOD WILL BE GENERALLY LIGHT OUT OF
THE SOUTH TO SOUTH-SOUTHEAST AT LESS THAN 10KTS...EXCEPT FOR A FEW
GUSTS TO 15-20KT EARLY THIS AFTERNOON.
&&
.PRELIMINARY POINT TEMPS/POPS...
DLH 65 80 63 79 / 40 30 70 50
INL 62 85 64 83 / 10 40 40 50
BRD 65 89 65 87 / 50 30 70 40
HYR 65 83 66 82 / 30 40 60 50
ASX 62 82 63 80 / 10 30 60 50
&&
.DLH WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
LS...NONE.
&&
$$
SHORT TERM...GSF
LONG TERM...JJM
AVIATION...JJM
AREA FORECAST DISCUSSION
NWS ST LOUIS MO
346 AM CDT SAT JUL 11 2015
.SHORT TERM: (THROUGH LATE THIS AFTERNOON)
ISSUED AT 330 AM CDT SAT JUL 11 2015
CLUSTER OF ELEVATED THUNDERSTORMS EXTENDING FROM SOUTHEAST IA INTO
NORTH CENTRAL MO ARE OCCURING IN ASSOCIATION WITH GOOD MOISTURE
CONVERGENCE ASSOCIATED WITH THE SOUTHWESTERLY LLJ. BOTH THE
DETERMINISTIC AND CAMS ARE IN RELATIVELY GOOD AGREEMENT SPREADING
THIS ACTIVITY EASTWARD THIS MORNING IN CONJUCTION WITH THE STEERING
FLOW ALOFT AND GRADUALLY VEERING LLJ. THERE IS SOME QUESTION ON
THE SOUTHERN EXTENT OF ANY STORM POTENTIAL. GIVEN THE CURRENT MID
CLOUD EXTENT AND VEERING LLJ, I THINK THE POTENTIAL FOR ISOLATED-
WIDELY SCATTERED STORMS EXISTS THIS MORNING AT LEAST DOWN TO THE
I-70 CORRIDOR WHICH IS JUST NORTH OF THE LIFTING WARM FRONT. IN
THE WAKE OF THE CLOUDS, CONVECTION AND LIFTING WARM FRONT, WARMING
LOW AND MID LEVELS SHOULD RESULT IN MUCH WARMER TEMPERATURES TODAY
AND MORE SEASONABLE FOR THIS TIME IN JULY.
GLASS
.LONG TERM: (TONIGHT THROUGH FRIDAY)
ISSUED AT 330 AM CDT SAT JUL 11 2015
THERE ARE LOTS OF QUESTIONS AND FORECAST CAVEATS TONIGHT INTO
TUESDAY. THE GENERAL PATTERN OF AN EXPANSIVE UPPER HIGH ANCHORED
ACROSS THE SOUTHERN PLAINS AND OUR LOCATION ON THE PERIPHERAL
NORTHWEST FLOW ALOFT POINTS TO BOTH BIG HEAT AND HUMIDITY AND
POTENTIAL THUNDERSTORM CHANCES. TO THIS END THE MODELS ARE QUITE
VARIED ON THE STRENGTH OF LOW-MID LEVEL WARMING AND EASTERN EDGE
OF THE STRONGER CAPPING AND PLACEMENT OF QPF. THE ECMWF SEEMS MOST
AGRESSIVE WITH THE EXTENT OF QPF INTO OUR CWA DURING MOST OF THE
FORECAST PERIODS. THE GENERAL THOUGHT IS THIS THAT THE VEERING
SOUTHWESTERLY LLJ AND ONLY MODERATELY WARM MID LEVEL TEMPS
TONIGHT ARE SUFFICIENT TO MERIT THUNDERSTORM CHANCES TONIGHT INTO
EARLY SUNDAY MORNING ACROSS PRIMARILY NORTHERN MO INTO CENTRAL IL.
BY SUNDAY AFTERNOON, STRONG WARMING IN THE LOW-MID LEVELS SHOULD
RESULT IN A FORMIDABLE CAP TO SURFACE BASED CONVECTION. A
RELATIVELY HOT AFTERNOON IS ON TAP WITH HIGHS IN THE 90S AND
AFTERNOON HEAT INDICES OF 100-103. THESE HI VALUES ARE LARGELY
BASED ON THE BELIEF THE MODELS ARE A BIT AGRESSIVE IN THE
MAGNITUDE OF THE SURFACE DEW POINTS. IF THE TDS ARE HIGHER THEN
WE MIGHT HAVE SOME 105 HIS. SUNDAY NIGHT INTO EARLY MONDAY A SHORT
WAVE TROF DIGGING FROM THE UPPER MS INTO THE LOWER GREAT LAKES
SHOULD LEAD TO HEIGHT FALLS ALOFT AND COOLING AND WESTWARD RETREAT
OF THE EDGE OF CAPPING, ALLOWING FOR A THREAT OF THUNDERSTORMS
PRIMARILY FOCUSED FROM FAR EASTERN MO INTO IL. THIS COULD BE A
COMBINATION OF SOUTHEAST MOVING CONVECTIVE COMPLEXES/CLUSTERS AND
NEW DEVELOPMENT.
MONDAY LOOKS TO BE THE HOTTEST DAY OVER THE NEXT 3 WITH CONTINUED
WARMING OF THE LOW-MID LEVELS - H85 TEMPS AOA +24 DEGC AND H7
TEMPS OF +12 TO +14 DEGC BY 00Z TUES. THIS LOOKS LIKE A DAY THAT
A HEAT ADVISORY WILL PROBABLY BE NEEDED PROVIDED THE OVERNIGHT
CONVECTION FROM SUNDAY SOMEHOW DOESN`T HAMPER IT. HEAT INDICES IN
MANY LOCATIONS SHOULD BE 105+. I DON`T ANTICIPATE MUCH CONVECTION
BEYOND THE MORNING RESIDUAL AND THE AFTERNOON CAP SHOULD BECOME
STOUT. SUNDAY NIGHT HOWEVER IT APPEARS THAT A SIGNIFICANT SEVERE
WEATHER EVENT COULD DEVELOP WITH ANOTHER SHORT WAVE TROF DIGGING
FROM THE UPPER MS VALLEY INTO THE LOWER GREAT LAKES AND OH VALLEY
PROVIDING FORCING AND WEAKENING THE CAP. STRONG INSTABILITY WILL
BE IN PLACE AND DEEP LAYER SHEAR IS RATHER STOUT AT 35-40 KTS. ALL
THE PARAMETERS ARE SUGGESTIVE OF A POTENTIAL DERECHO SWEEPING FROM
EASTERN IA/NORTHWEST IL SOUTHEASTWARD AND IMPACTING FAR EASTERN MO
INTO IL.
A FRONTAL BOUNDARY FINALLY SINKS INTO THE AREA TUESDAY AND THEN
WAVERS NORTH AND SOUTH DURING THE WEEK RESULTING IN PROLONGED
THUNDERSTORM CHANCES IN THE VICINITY OF THE BOUNDARY AND
SEASONABLY HOT TEMPERATURES TO THE SOUTH OF IT.
GLASS
&&
.AVIATION: (FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT)
ISSUED AT 1039 PM CDT FRI JUL 10 2015
SHORT RANGE MODELS (RAP, HRRR) ARE AGREEING THE SHOWERS AND
THUNDERSTORMS WILL DEVELOP ALONG THE WARM FRONT AS IT MOVES NORTH
OVERNIGH. THE ATMOSPHERE LOOK BEST OR UIN WHERE THERE APPEARS TO
BE BETTER DEEP MOISTURE CONVERGENCE. TIMEING ON CURRENT TAF LOOKS
GOOD WITH SHROT RANGE MODELS SO WILL CHANGE PROB30 TO A TEMPO
GROUP. A VCSH FOR COU MAY BE ALL THAT IS NEEDED FOR A COUPLE OF
HOURS AS IT LOOKS LIKE THE DEVELOPMENT WILL BE NORTH AND EAST.
WILL BRING THE FRONT THROUGH COU AT 14Z AND UIN AND 18Z.
SPECIFICS FOR KSTL: RAP AND HRRR DEVELOP PRECIPITATON NW-SE ALONG
THE ADVANCING WARM FRONT. IF IT HAPPENS IT LOOKS TO BE 10Z TO 14Z.
STILL, CONFIDENCE IS NOT HIGH ENOUGH TO GO ABOVE VICINITY FOR
NOW. WILL DELAY THE WIND SHIFT WITH THE WARM FRONT TO 18Z
FOLLWING THE RAP/HRRR.
JPK
&&
.LSX WATCHES/WARNINGS/ADVISORIES:
MO...NONE.
IL...NONE.
&&
$$
WFO LSX
AREA FORECAST DISCUSSION
NWS OMAHA/VALLEY NE
649 PM CDT SUN JUL 12 2015
.SHORT TERM...(TONIGHT THROUGH WEDNESDAY)
ISSUED AT 319 PM CDT SUN JUL 12 2015
FEELS LIKE TEMPERATURES OUT THERE ARE VERY HOT...WITH MANY LOCATIONS
REPORTING HEAT INDICES AROUND 105 AT 3 PM. WE ARE ANTICIPATING THIS
AGAIN MONDAY FOR QUITE A FEW COUNTIES IN OUR SOUTHEASTERN CWA AND
IS THE MAIN CONCERN IN THE NEXT 24 HOURS.
LATEST WATER VAPOR IMAGERY AND RAP 500MB ANALYSIS SHOWS LARGE HIGH
PRESSURE DOME OVER THE SOUTHERN PLAINS WITH A SHORTWAVE TROUGH
MOVING ACROSS THE NORTHERN PLAINS. VERY HIGH SFC DEWPOINTS REMAIN
OVER THE AREA THIS AFTERNOON WITH READINGS VARYING BETWEEN THE
LOWER 70S IN OUR WEST TO THE UPPER 70S IN OUR EAST. WE ALSO HAVE
THE SPORADIC IOWA AWOS VALUES IN THE LOW 80S. LATEST SURFACE
ANALYSIS SHOWS LOW PRESSURE CENTERED OVER SOUTHEASTERN NORTH
DAKOTA WITH A SECONDARY LOW ACROSS SOUTHWEST KANSAS. A TROUGH IN
BETWEEN THESE TWO AREAS CURRENTLY EXTENDS ACROSS OUR FAR
NORTHWESTERN COUNTIES AND THIS FEATURE WILL CONTINUE TO SLOWLY
PUSH EAST ACROSS THE FORECAST AREA THROUGH MONDAY...BRINGING IN
LOWER DEWPOINTS TO THE AREA.
TEMPERATURES SHOULD MIX OUT INTO THE UPPER 90S NEAR THE BOUNDARY
MONDAY. COMBINED WITH MID-UPPER 70S DEWPOINTS IN THE SOUTHEASTERN
HALF OF THE CWA...WE SHOULD PUSH HEAT INDICES INTO THE ADVISORY
CATEGORY ONCE AGAIN SO DID HOIST AN ADVISORY FOR MONDAY.
WARM CONDITIONS WILL CONTINUE ON TUESDAY ALTHOUGH WILL NOT BE QUITE
AS HOT. HEAT INDICES WILL BE LOWER AS WELL WITH DEWPOINTS IN THE
60S. BY TUESDAY NIGHT...THE FIRST IN A SERIES OF SEVERAL
SHORTWAVES WILL BE PASSING THROUGH THE MID LEVELS. WITH AMPLE
MOISTURE IN THE ATMOSPHERE...WE CANNOT RULE OUT PCPN CHANCES WITH
ANY OF THESE WAVES. CONVECTION MAY BEGIN AS EARLY AS TUESDAY
EVENING OVER THE HIGH PLAINS ASSOCIATED WITH THE FIRST WAVE...THEN
SPREAD EAST INTO THE CWA OVERNIGHT TUESDAY NIGHT INTO WEDNESDAY
MORNING.
.LONG TERM...(WEDNESDAY NIGHT THROUGH SUNDAY)
ISSUED AT 319 PM CDT SUN JUL 12 2015
TSTM CHANCES CONTINUE WEDNESDAY NIGHT AS ANOTHER STRONG SHORTWAVE
MOVES ACROSS THE HIGH PLAINS DURING THE AFTERNOON WEDNESDAY AND
INTO OUR CWA WEDNESDAY EVENING. A STRONG SOUTHWESTERLY LOW LEVEL
JET SHOULD AID CONTINUED CONVECTION THROUGH THE OVERNIGHT HOURS.
THE AREA WILL REMAIN IN WEST/SOUTHWESTERLY FLOW ALOFT THROUGH NEXT
WEEKEND BRINGING SEVERAL SMALL CHANCES OF TSTMS THROUGH THE
PERIOD. TEMPS SHOULD BE QUITE SEASONABLE FOR THIS TIME OF YEAR.
&&
.AVIATION...(00Z TAFS FOR KOFK...KLNK AND KOMA.)
ISSUED AT 642 PM CDT SUN JUL 12 2015
VFR CONDITIONS WILL PREVAIL AT KOFK...KOMA...AND KLNK THROUGH THE
FORECAST PERIOD. WEAK SURFACE FRONT WILL MOVE ACROSS TEASTERN
NEBRASKA AND WESTERN IOWA ON MONDAY. WINDSHIFT IS EXPECTED TO
OCCUR AT ALL SITES BETWEEN 15 AND 18Z.
&&
.OAX WATCHES/WARNINGS/ADVISORIES...
NE...HEAT ADVISORY UNTIL 8 PM CDT THIS EVENING FOR NEZ011-012-015>018-
030>034-042>045-050>053-065>068-078-088>093.
HEAT ADVISORY FROM 1 PM TO 8 PM CDT MONDAY FOR NEZ045-051>053-
066>068-078-088>093.
IA...HEAT ADVISORY UNTIL 8 PM CDT THIS EVENING FOR IAZ043-055-056-069-
079-080-090-091.
HEAT ADVISORY FROM 1 PM TO 8 PM CDT MONDAY FOR IAZ055-056-069-
079-080-090-091.
&&
$$
SHORT TERM...KERN
LONG TERM...KERN
AVIATION...SMITH
AREA FORECAST DISCUSSION
NWS ALBUQUERQUE NM
554 PM MDT SUN JUL 12 2015
.AVIATION...
00Z TAF CYCLE
SHOWERS AND THUNDERSTORMS ARE MOST PREVALENT ACROSS THE WESTERN
HALF OF NEW MEXICO WHERE THE DEEPEST SUBTROPICAL MOISTURE PLUME
RESIDES. THESE STORMS WILL CONTINUE TO DRIFT NORTHWARD THROUGH
THE LATE EVENING...GRADUALLY DECREASING IN COVERAGE TOWARD
MIDNIGHT AND THE EARLY MORNING HOURS. THE MAIN HAZARDS WILL BE
GUSTY DOWNBURST WINDS...BRIEF REDUCTIONS TO CEILINGS/VISIBILITY
DURING DOWNPOURS...AND SMALL HAIL. A LULL...OR AT LEAST A LARGE
REDUCTION IN THUNDERSTORM ACTIVITY IS EXPECTED INTO THE EARLY
MORNING HOURS MONDAY...BUT SCATTERED TO NUMEROUS THUNDERSTORMS
WILL REDEVELOP MONDAY AFTERNOON. STORMS ON MONDAY WILL AGAIN FAVOR
THE WESTERN TO CENTRAL AREAS OF NEW MEXICO AGAIN.
52
&&
.PREV DISCUSSION...348 PM MDT SUN JUL 12 2015...
.SYNOPSIS...
AS UPPER LEVEL HIGH PRESSURE REMAINS ANCHORED OVER THE SOUTHERN
PLAINS A RATHER CLASSIC MONSOON MOISTURE PLUME WILL CONTINUE TO
BRING SCATTERED THUNDERSTORMS WITH LOCALLY HEAVY RAINFALL TO MUCH
OF CENTRAL AND WESTERN NEW MEXICO THIS EVENING THROUGH AT LEAST
MID WEEK. STORM COVERAGE IS EXPECTED TO TREND DOWN SOMEWHAT THURSDAY
AS DRY AIR ALOFT WORKS IN FROM THE WEST. THE MOISTURE PLUME RE-
ESTABLISHES ITSELF FRIDAY AND SATURDAY FOR A RETURN TO SCATTERED
ACTIVITY.
&&
.DISCUSSION...
UPPER LEVEL HIGH CENTERED NEAR LUBBOCK TX THIS AFTERNOON. MODELS
IN VERY GOOD AGREEMENT THAT DEEP SUBTROPICAL MOISTURE WILL CONTINUE
STREAMING INTO WESTERN AND CENTRAL NM THROUGH AT LEAST WEDNESDAY.
BOTH 18Z NAM12 AND 20Z HRRR PICKING UP ON PERTURBATION/VORT LOBE
CURRENTLY MOVING INTO FAR SE ARIZONA. BOTH MODELS BRING THIS
FEATURE INTO SWRN AND WEST CENTRAL NM AFTER MIDNIGHT...HELPING TO
KEEP SHOWERS AND STORMS GOING THERE THROUGH EARLY MONDAY MORNING.
MODELS CONTINUE TO SHIFT THE UPPER HIGH SLIGHTLY EASTWARD MONDAY
AND TUESDAY...ALLOWING STORMS TO PROPAGATE EWD MORE EASILY INTO
THE NE AND EAST-CENTRAL PLAINS. MODELS REMAIN IN RELATIVELY GOOD
AGREEMENT THAT SOME DRIER AIR ALOFT WILL ATTEMPT TO WORK INTO NW
AND NORTH-CENTRAL NM THURSDAY...LEADING TO A POSSIBLE DOWN DAY
THERE. THE DEEP MOISTURE PLUME HANGS TOUGH ELSEWHERE.
12Z GFS PROGGING AN INCREASE IN SELY WINDS BETWEEN THE UPPER HIGH
AND WHAT IS NOW TROPICAL STORM DOLORES. THIS INCREASING FLOW
HAS THE POTENTIAL TO TAP DEEP SUBTROPICAL MOISTURE AND DEEP
CONVECTION OVER FAR NW MEXICO AND SRN ARIZONA. 12Z GFS GOES SO FAR
AS TO DEVELOP A WARM CORE LOW OVER SE AZ/WRN NM THURSDAY NIGHT
AND FRIDAY. SUCH A FEATURE WOULD RESULT IN A MARKED INCREASE IN
HEAVY RAIN/FLASH FLOODING POTENTIAL FRIDAY INTO FRIDAY NIGHT. TOO
FAR OUT AT THIS POINT TO NAIL DOWN THE TIMING OF A FEATURE YET TO
DEVELOP BUT IT WILL BE CLOSELY MONITORED IN THE COMING DAYS.
SUNDAY COULD BE THE NEXT DOWNDAY AS THE UPPER HIGH ATTEMPTS TO
RETROGRADE WWD INTO SRN AZ. CONFIDENCE IN THIS SOLUTION REMAINS
LOW AS 12Z ECMWF KEEPS THE UPPER HIGH CENTER OVER SE NM...KEEPING
WRN AND NRN NM ACTIVE SUNDAY INTO EARLY NEXT WEEK.
33
&&
.FIRE WEATHER...
THE SHOWER AND THUNDERSTORM CROP TODAY IS GREATER IN
NUMBER AND AT LEAST AS VIGOROUS AS WAS THE CASE SAT...MOST TODAY
BEING ACROSS THE WEST TWO THIRDS OF THE STATE. MONSOONAL MOISTURE
PLUME HOLDING FIRM ACROSS THIS GENERAL AREA AND INTO EAST AZ. NO
MAJOR CHANGE IN OVERALL PATTERN FOR THE WORK WEEK...THOUGH FCST
MODELS ARE HINTING AT ANY SIGNIFICANT DRYING TO BE THU TO FRI AND
MAY BE SHORTER IN DURATION THAN WHAT WAS INDICATED THE PAST DAY OR
TWO. LESS INDICATION THAN 12 TO 24 HRS AGO OF A WEAK BACK DOOR FRONT
PUSHING INTO NE NM NEAR MON TO MON NIGHT PERIOD...THOUGH IF
CONVECTION DOES RAMP UP IN SE CO THERE STILL WILL LIKELY BE AT LEAST
A STORM COMPLEX OUTFLOW BOUNDARY INTO THE FAR NE. IF IT DOES NOT
HAPPEN THEN STORM COVERAGE IN NE NM MAY NOT INCREASE ALL THAT MUCH.
FCST MODELS FOR THE MOST PART CONTINUING TO DELAY...A FEW EVEN
ELIMINATE...THE BUILDING OF THE UPPER HIGH CENTER OVER THE STATE...
LEAVING THE MOISTURE PLUME MORE INTACT OVER WEST HALF OF NM. NEXT
WEEKEND INTO MID NEXT WEEK A TROPICAL SYSTEM IS STILL INDICATED AS
MOVING UP AND OVER THE RIDGE INTO CA WITH THE BULK OF ITS MOISTURE
WELL TO OUR WEST.
HIGH TEMPERATURES WILL REMAIN BELOW AVERAGE WEST...BUT RISE TO
AVERAGE OR SLIGHTLY ABOVE...THIS WEEK. VENT RATES GENERALLY GOOD TO
EXCELLENT ALTHOUGH SOME POCKETS OF FAIR TO POOR RATES WILL EXIST
NORTH AND WEST THROUGH WED...WITH SOME DECREASE POSS THU.
43
&&
.ABQ WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS ALBUQUERQUE NM
300 PM MDT SAT JUL 11 2015
.SYNOPSIS...
ANOTHER ROBUST ROUND OF THUNDERSTORMS UNDERWAY THIS AFTERNOON...
FAVORING WESTERN PORTIONS OF THE AREA AS HIGH PRESSURE IN THE MID
AND UPPER LEVELS OF THE ATMOSPHERE STRENGTHENS OVER EASTERN
PORTIONS AND SHUTS DOWN CHANCES THERE. A WARMING TREND IS
UNDERWAY FOR MUCH OF THE AREA AND WILL SEND HIGH TEMPERATURES
ABOVE NORMAL ACROSS EASTERN NEW MEXICO BY TOMORROW...AND HOLD AT
OR ABOVE NORMAL THROUGH THE UPCOMING WORK WEEK. THUNDERSTORMS WILL
FAVOR CENTRAL AND WESTERN NEW MEXICO THROUGH MONDAY...THEN SHIFT
TO INCLUDE NORTHERN PORTIONS OF THE AREA ON TUESDAY AND WEDNESDAY.
ONLY THE EAST CENTRAL AND SOUTHEAST PLAINS LOOK TO MISS OUT ON
RAIN OVER THE NEXT SEVEN DAYS.
&&
.DISCUSSION...
A MONSOON MOISTURE-RICH ATMOSPHERE PERSIST ACROSS OUR AREA WITH
ABOVE NORMAL PWATS. TODAY`S ROUND OF STORMS FAVORS WESTERN
PORTIONS OF OUR AREA...WHERE SHEAR IS ALLOWING FOR STRONG
SUSTAINED UPDRAFTS AND A FEW SEVERE STORMS. WILL BE INTERESTING TO
SEE IF THE CURRENT CROP OF STORMS CAN MAKE IT ACROSS THE RIO
GRANDE VALLEY AND IMPACT THE I-25 CORRIDOR BETWEEN SOCORRO...
BELEN AND ALBUQUERQUE. THE 19Z HRRR SHOWS THIS POTENTIAL SCENARIO
BETWEEN 23-01Z. LOOKING MORE LIKE A GOOD BET HERE IN THE
ALBUQUERQUE METRO WITH A LAST LOOK AT THE LATEST RADAR TRENDS AT
3 PM MDT.
SUNDAY LOOKS TO BE DIFFERENT THAN TODAY AS THE UPPER HIGH...
CURRENTLY OVER EAST TEXAS AND LOUISIANA...BUILDS WESTWARD TOWARD
EASTERN NEW MEXICO AND WEST TEXAS. THIS INCREASE IN PRESSURE
HEIGHTS WILL CORRESPOND WITH INCREASING HIGH TEMPERATURES...
MAINLY EAST...AND A FOCUSING OF STORMS ACROSS WESTERN NEW MEXICO
AND EASTERN ARIZONA. SHEAR...BOTH SPEED AND DIRECTIONAL...WILL BE
CONSIDERABLY LESS SUNDAY COMPARED TO TODAY WITH THE UPPER HIGH
MOVING-IN. SO...EXPECT A FEW ISOLATED STRONG STORMS WITH SLOWER
MOTION TO TILT THE THREAT TOWARD LOCALLY HEAVY RAINFALL WITH MUCH
LESS POTENTIAL FOR SEVERE.
PRESSURE HEIGHTS TREND BACK DOWN MON/TUE AS THE UPPER HIGH BACKS
OFF TO THE EAST A BIT...ALLOWING THE MONSOON MOISTURE PLUME TO
TILT BACK OVER CENTRAL AND NORTHERN PORTIONS OF OUR CWFA...
LEAVING-OUT ONLY THE SOUTHEAST IN TERMS OF RAIN CHANCES. A FAIRLY
TYPICAL MONSOON PATTERN TO THEN PERSIST THROUGH THE END OF THE
WORK-WEEK...ALTHOUGH NOT THE IDEAL PLUME POSITIONING WITH DEEP
SOUTHERLY FLOW. OUR FORECAST TRENDS TOWARD CLIMO FOR FRI/SAT.
11
&&
.FIRE WEATHER...
WETTING RAIN IN THE FORM OF SHOWERS AND THUNDERSTORMS WILL
CONTINUE TODAY THROUGH MONDAY...ESPECIALLY WESTERN AND CENTRAL
ZONES...THOUGH COVERAGE IS EXPECTED TO DOWN TREND. FOR THE
REMAINDER OF THE WORK WEEK...RECYCLING OF MOISTURE WILL SUPPORT
SHOWERS AND THUNDERSTORMS OVER THE HIGHER TERRAIN AND NORTH...WITH
LESS ACTIVITY EAST CENTRAL ZONES. TEMPERATURES TO WARM A
BIT...FINALLY REACHING ABOVE AVERAGE LEVELS ACROSS THE EAST ON
SUNDAY...WHILE REMAINING BELOW AVERAGE ACROSS THE WEST. HAINES
VALUES ARE FORECAST TO INCREASE...WITH AREAS OF 5 TUESDAY THROUGH
FRIDAY MAINLY ACROSS THE NORTH. VENTILATION TO GENERALLY RANGE
FROM GOOD TO EXCELLENT THROUGH THE FORECAST PERIOD...WITH AREAS OF
POOR TO FAIR ACROSS WEST CENTRAL ZONES ON SUNDAY AND MONDAY AND
ACROSS SOUTHWEST AND SOUTH CENTRAL ZONES THURSDAY AND FRIDAY.
A BROAD UPPER LEVEL TROUGH REMAINS OVER THE WEST COAST WITH AN
UNSEASONABLY STRONG JET STRETCHED FROM SOUTHERN CALIFORNIA TO THE
GREAT PLAINS. UPPER LEVEL HIGH PRESSURE OVER THE SOUTHEAST STATE
CONTINUES TO GRADUALLY STRENGTHEN AND SHIFT TO THE WEST WITH THE
CENTER CURRENTLY POSITIONED OVER EAST TEXAS. THIS PATTERN IS
SUPPORTING A FAIRLY ROBUST MONSOON SURGE FROM MEXICO INTO NEW
MEXICO. THUNDERSTORMS THIS AFTERNOON HAVE FAVORED THE WEST. RH
RECOVERIES TODAY WILL BE GOOD TO EXCELLENT ALL ZONES.
AS THE UPPER CONTINUES TO SHIFT TO THE WEST...THE PLUME WILL BE
NUDGED TO THE WEST AS WELL SUCH THAT DRIER CONDITIONS MOVE INTO THE
EASTERN PLAINS WHILE THE WEST WILL SEE CONTINUED CONVECTIVE WETTING
RAIN MAINLY OVER THE HIGHER TERRAIN. A WEAK WIND SHIFT INTO THE
NORTHEAST COULD BE A FOCUS FOR SOME PRECIPITATION THERE ON MONDAY
AND AN UPPER LEVEL DISTURBANCE JUST NORTH OF THE STATE ON TUESDAY
COULD ALSO HELP EXTEND THE CHANCES OF WETTING RAIN ACROSS THE NORTH
AND NORTHEAST.
EXTENDED MODELS INDICATE THAT THE UPPER HIGH COULD WEAKEN/FLATTEN
MID TO LATE WEEK AS SOME ENERGY EJECTS OUT OF THE WESTERN TROUGH AND
OVER THE ROCKIES. THE MONSOON PLUME COULD REPOSITION OVER NEW
MEXICO...THOUGH MOISTURE LOOKS SOMEWHAT LIMITED AT THIS TIME.
05
&&
.AVIATION...
18Z TAF CYCLE
AFTERNOON AND EVENING SHOWERS AND THUNDERSTORMS TO INITIALLY FAVOR
THE WESTERN HIGHER TERRAIN WITH A STEERING FLOW TO THE NORTHEAST
AROUND 20KT. COVERAGE TO INCREASE THROUGH THE AFTERNOON INTO
CENTRAL AND EASTERN ZONES. THE STRONGEST CELLS WILL PRODUCE LOCAL
HEAVY RAIN WITH MVFR CIGS AND VISIBILITIES AND OCCASIONAL MOUNTAIN
OBSCURATIONS. OVERNIGHT...SOME LINGERING RAIN SHOWERS ARE MOST
LIKELY ACROSS THE NORTH. ANOTHER ROUND OF SHOWERS AND
THUNDERSTORMS TO START DEVELOPING BEFORE NOON ON SUNDAY...
ESPECIALLY OVER THE WESTERN AND SOUTHCENTRAL HIGHER TERRAIN.
05
&&
.PRELIMINARY POINT TEMPS/POPS...
FARMINGTON...................... 57 87 59 86 / 20 20 20 30
DULCE........................... 48 81 51 81 / 20 20 30 30
CUBA............................ 49 81 51 80 / 50 40 30 40
GALLUP.......................... 52 83 54 83 / 30 30 30 30
EL MORRO........................ 51 81 51 80 / 40 40 30 50
GRANTS.......................... 54 82 53 83 / 30 30 30 40
QUEMADO......................... 54 81 55 81 / 40 30 30 40
GLENWOOD........................ 56 87 56 87 / 30 40 30 50
CHAMA........................... 45 78 48 78 / 30 50 40 50
LOS ALAMOS...................... 56 83 59 84 / 50 50 40 50
PECOS........................... 53 83 56 83 / 30 20 30 30
CERRO/QUESTA.................... 48 80 51 80 / 30 50 40 40
RED RIVER....................... 44 69 45 69 / 50 50 50 50
ANGEL FIRE...................... 48 71 49 71 / 50 50 50 50
TAOS............................ 48 84 52 84 / 10 20 20 30
MORA............................ 52 79 53 79 / 50 40 40 50
ESPANOLA........................ 53 87 57 87 / 30 20 30 30
SANTA FE........................ 57 84 59 85 / 20 20 20 20
SANTA FE AIRPORT................ 54 86 57 87 / 20 20 30 20
ALBUQUERQUE FOOTHILLS........... 62 88 65 89 / 30 20 20 20
ALBUQUERQUE HEIGHTS............. 63 89 66 90 / 20 20 20 10
ALBUQUERQUE VALLEY.............. 61 91 63 92 / 20 20 20 10
ALBUQUERQUE WEST MESA........... 62 90 65 90 / 20 20 20 20
LOS LUNAS....................... 62 90 63 91 / 20 20 20 20
RIO RANCHO...................... 61 89 64 90 / 20 20 20 20
SOCORRO......................... 62 92 64 93 / 20 20 20 20
SANDIA PARK/CEDAR CREST......... 56 83 58 84 / 40 20 30 20
TIJERAS......................... 55 86 57 87 / 40 20 20 20
MORIARTY/ESTANCIA............... 52 86 53 87 / 20 20 20 10
CLINES CORNERS.................. 55 84 57 84 / 20 20 20 10
GRAN QUIVIRA.................... 57 84 58 86 / 30 20 20 20
CARRIZOZO....................... 61 88 62 90 / 20 20 10 10
RUIDOSO......................... 56 79 58 83 / 30 30 10 20
CAPULIN......................... 56 85 58 85 / 10 20 20 30
RATON........................... 52 88 56 88 / 10 10 20 10
SPRINGER........................ 54 89 57 89 / 5 10 20 10
LAS VEGAS....................... 54 84 55 85 / 10 10 20 10
CLAYTON......................... 61 96 65 95 / 5 5 20 10
ROY............................. 61 90 61 91 / 5 5 10 5
CONCHAS......................... 65 96 66 98 / 5 5 10 5
SANTA ROSA...................... 65 95 66 96 / 5 5 10 5
TUCUMCARI....................... 68 98 69 99 / 5 5 10 5
CLOVIS.......................... 65 93 65 96 / 10 5 5 5
PORTALES........................ 66 94 67 97 / 10 5 5 5
FORT SUMNER..................... 66 94 66 97 / 5 5 10 5
ROSWELL......................... 68 97 67 100 / 10 5 5 5
PICACHO......................... 61 89 62 92 / 10 10 10 10
ELK............................. 59 85 59 88 / 10 20 10 20
&&
.ABQ WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
11
AREA FORECAST DISCUSSION
NWS ALBUQUERQUE NM
1143 PM MDT FRI JUL 10 2015
.AVIATION...
06Z TAF CYCLE
ROUNDS OF TS/SH WILL IMPACT THE SE PLAINS THROUGH THE REST OF THE
OVERNIGHT. ROW STANDS A GOOD CHANCE TO BE IMPACTED. OTHERWISE VERY
LIMITED CONVECTION ACROSS THE FORECAST AREA. PERHAPS A STRAY
STRIKE OR TWO ACROSS THE WESTERN HIGHLANDS. ISOLD TO SCT STORMS
WILL ONCE AGAIN FIRE UP ACROSS THE AREA ON SATURDAY. USING
VCTS/VCSH AT MOST OF THE TERMINAL SITES EXCEPT FOR LVS. IT APPEARS
THAT THE HIGHLANDS WEST OF LVS SHOULD HAVE ANOTHER DOWN DAY. BASED
ON THE STEERING FLOW...INSTABILITY AND MOISTURE AVAILABILITY...ROW
HAS THE BEST CHANCE OF BEING DIRECTLY IMPACTED BUT REALLY CANT
RULE OUT MOST OF THE TERMINAL SITES.
50
&&
.PREV DISCUSSION...304 PM MDT FRI JUL 10 2015...
.SYNOPSIS...
SHOWERS AND THUNDERSTORMS WILL CONTINUE THROUGH THE WEEKEND AS
THE MONSOON MOISTURE PLUME STRETCHES FROM SOUTH TO NORTH OVER THE
STATE. LOCALLY HEAVY RAINFALL WILL BE POSSIBLE WITH ANY OF THE
STRONGER STORMS...ALONG WITH GUSTY WINDS AND SMALL HAIL. UPPER
LEVEL HIGH PRESSURE WILL DRIFT WEST THROUGH NEXT WEEK AND ALLOW
FOR DRIER AND HOTTER CONDITIONS TO RETURN. ISOLATED TO SCATTERED
SHOWERS AND STORMS WILL STILL DEVELOP AROUND THE HIGH TERRAIN...
ESPECIALLY OVER WESTERN NEW MEXICO.
&&
.DISCUSSION...
AN UNSEASONABLY DEEP UPPER LEVEL LOW OVER THE GREAT BASIN IS
FORCING A STRONG 40-60KT UPPER JET OVER AZ/NM. A 594DM H5 UPPER
HIGH DRIFTING WEST OVER EAST TX IS TAPPING A JUICY ATMOSPHERE FROM
MEXICO AND SHIFTING IT NORTHWARD INTO THE FASTER UPPER LEVEL FLOW.
STRONG DIFFLUENCE AND TERRAIN CIRCULATIONS WITH AFTERNOON HEATING
IN THIS PATTERN IS FORCING SEVERAL STRONG TO EVEN SEVERE STORMS
ACROSS THE SW PORTION OF THE STATE. OTHERWISE STORM COVERAGE IS
LESS TODAY AND ACTIVITY IS BUMPING ALONG QUICKLY FOR JULY...THUS
LIMITING THE FLASH FLOOD THREAT. HRRR GUIDANCE SHOWS CONVECTIVE
ACTIVITY MAKING IT INTO THE RIO GRANDE VALLEY AND EASTERN PLAINS
BETWEEN 3PM AND 7PM.
NOT MUCH CHANGE ANTICIPATED SATURDAY WITH THE OVERALL CIRCULATION
PATTERN REMAINING QUASI-STATIONARY. STORM MOTIONS MAY BECOME A BIT
MORE SOUTH TO NORTH AS THE UPPER HIGH DRIFTS WEST AND IMPINGES ON
THE UPPER LEVEL SW FLOW. BY SUNDAY...ANOTHER BURST IS ADVERTISED BY
MID-RANGE MODEL GUIDANCE. INCREASED POPS AGAIN SUNDAY WITH LOCALLY
HEAVY RAINFALL THREAT INCREASING. FOR THE REMAINDER OF NEXT WEEK...
A SLOW DRYING AND WARMING TREND IS ON TAP. HIGH TEMPS WILL TREND TO
NEAR NORMAL WITH SLOW-MOVING STORMS FAVORING HIGH TERRAIN AREAS.
GUYER
&&
.FIRE WEATHER...
DAILY ROUNDS OF WETTING RAIN IN THE FORM OF THUNDERSTORMS AND
SHOWERS WILL CONTINUE THROUGH THE FORECAST PERIOD...THOUGH COVERAGE
WILL LIKELY DECREASE AS DRIER AND WARMER CONDITIONS DEVELOP. BY
EARLY NEXT WEEK...EASTERN ZONES WILL SEE THE FEWEST STORMS WHILE
WESTERN AND CENTRAL ZONES REMAIN MORE ACTIVE. TEMPERATURES WILL
FINALLY REACH NORMAL OR HIGHER LEVELS ACROSS THE EAST BY SUNDAY AND
MUCH OF THE STATE BY THURSDAY. VENTILATION LOOKS TO BE GENERALLY
GOOD TO EXCELLENT MOST DAYS WITH LOWER VALUES...AND SOME AREAS OF
POOR TO FAIR VENTILATION ON SUNDAY AND THURSDAY.
INTERESTING PATTERN FOR JULY WITH AN UNSEASONABLY DEEP CLOSED LOW
POSITIONED CENTERED OVER THE GREAT BASIN AND THE ASSOCIATED UPPER
JET EXTENDED FROM NORTHERN BAJA...ACROSS ARIZONA AND OVER NORTHWEST
NEW MEXICO. SHOWERS AND THUNDERSTORMS THIS AFTERNOON ARE MOVING
FAIRLY QUICKLY TO THE NORTHEAST...AND SOME ARE PRODUCING HAIL AND
LOCALLY HEAVY RAIN. LOWER DEWPOINTS NOTED OVER ARIZONA THIS MORNING
HAVE NOT REALLY TRANSLATED INTO WESTERN ZONES TODAY. THUS...
OVERNIGHT RH RECOVERIES LOOK TO BE GOOD TO EXCELLENT ALL ZONES.
MEANWHILE...UPPER LEVEL HIGH PRESSURE CONTINUES TO BUILD OVER THE
SOUTHEAST STATES...MAINTAINING THE FLUX OF MONSOON MOISTURE FROM
MEXICO INTO NEW MEXICO. MODELS CONTINUE TO DEPICT THE UPPER HIGH
BUILDING OVER TEXAS...RESULTING IN A WESTWARD NUDGE OF THE MONSOON
PLUME. SATURDAY LOOKS TO BE FAIRLY ACTIVE MOST ZONES...WITH THE
EXTREME NORTHWEST AND NORTHEAST CORNERS LEAST FAVORED. BY SUNDAY
THROUGH TUESDAY...EASTERN ZONES LOOK TO REMAIN FAIRLY DRY WITH THE
HIGH TERRAIN OF WESTERN AND CENTRAL ZONES FAVORED.
05
&&
.ABQ WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS BURLINGTON VT
347 PM EDT SAT JUL 11 2015
.SYNOPSIS...
A RIDGE OF HIGH PRESSURE BOTH AT THE SURFACE AND ALOFT
WILL CONTINUE TO PROVIDE THE NORTH COUNTRY WITH ABOVE NORMAL
TEMPERATURES AND MAINLY DRY CONDITIONS THROUGH EARLY MONDAY. A FEW
ISOLATED SHOWERS ARE POSSIBLE TONIGHT ACROSS NORTHERN VERMONT AND
AGAIN ON SUNDAY AND MONDAY AFTERNOONS. A COLD FRONT WILL PROVIDE
BETTER CHANCES FOR SHOWERS ON TUESDAY INTO WEDNESDAY...ALONG WITH
COOLER TEMPERATURES.
&&
.NEAR TERM /UNTIL 6 AM SUNDAY MORNING/...
AS OF 330 PM EDT SATURDAY...BIG PICTURE ON WATER VAPOR SHOWS NW
FLW ALOFT WITH BUILDING MID/UPPER LVL RIDGE ACROSS THE OHIO
VALLEY/CENTRAL GREAT LAKES. HAVE NOTED A VERY WEAK 5H VORT WITH SOME
MID LVL MOISTURE NEAR MANIWAKI, QC...WITH GENERAL SOUTHEAST MOVEMENT
TWD OUR NORTHERN CWA BY TONIGHT. THE LATEST GFS AND HRRR MODELS SHOW
VERY WEAK QPF OUTPUT FROM THIS FEATURE...WITH GREATEST CHCS OF A
SHOWER ACROSS NEK OF VT. WL CONTINUE WITH PREVIOUS FCSTER THINKING A
MENTION SCHC TO VERY LOW CHC POPS ACROSS OUR NORTHERN CWA TONIGHT.
ANY QPF WL BE LIGHT <0.10". EXPECTING LOWS MAINLY IN THE 60S WITH
50S IN THE COOLER MTN VALLEYS. HAVE NOTED SFC DWPTS 3 TO 5 DEGREES
WARMER THAN YESTERDAY AT THIS TIME...BUT WITH SOME BL WINDS BTWN 10
AND 15 KNOTS AND NO RAIN IN THE PAST 30 HOURS...WL NOT MENTION FOG
IN FCST AT THIS TIME.
&&
.SHORT TERM /6 AM SUNDAY MORNING THROUGH MONDAY NIGHT/...
AS OF 330 PM EDT SATURDAY...MID/UPPER LVL RIDGE BUILDS ACROSS OUR
CWA ON SUNDAY WITH WARMING TEMPS AND SUBSIDENCE ALOFT.
HOWEVER...ANOTHER VERY WEAK 5H VORT ALONG WITH STRONG SFC HEATING
HELPING TO CREATE SOME INSTABILITY MAY PRODUCE A FEW MORE SHOWERS
ON SUNDAY AFTN. HAVING DIFFICULTIES SEEING MUCH AREAL COVERAGE OR
INTENSITY TO SHOWERS OR STORMS...GIVEN DRY AIR ALOFT AND PROGGED
500MB TEMPS NEAR -10C. IN ADDITION...SOUNDINGS ARE NOT VERY
IMPRESSIVE WITH INSTABILITY PARAMETERS GIVEN WARM TEMPS ALOFT. SO
WILL MENTION JUST ISOLATED CHCS ATTM FOR SUNDAY. GFS QPF FIELDS
SEEM OVERDONE GIVEN POSITION OF RIDGE AXIS DIRECTLY OVERHEAD AND
ASSOCIATED SUBSIDENCE. PROGGED 85H TEMPS WARM ANOTHER DEGREE FROM
SATURDAY...AND WILL SUPPORT HIGHS IN THE LOWER 80S MTN VALLEY
TOWNS TO M/UPPER 80S CHAMPLAIN AND SAINT LAWRENCE VALLEYS.
FORECAST CHALLENGE ON MONDAY WILL BE CHANCES FOR ADDITIONS SHOWERS
AND STORMS ASSOCIATED WITH S/W ENERGY UNDERCUTTING MID/UPPER LVL
RIDGE. GFS CONTS TO BE THE MOST AGGRESSIVE WITH S/W ENERGY WHICH IS
CURRENTLY OVER IOWA AND PRODUCING AREAS OF QPF ACROSS OUR CWA ON
MONDAY AFTN. INSTABILITY PARAMETERS ARE MODEST WITH CAPE VALUES
BETWEEN 400 AND 800 J/KG AND LIS BTWN -2C AND -4C OFF THE
GFS...WHILE THE NAM SHOWS GREATER SFC BASED CAPE VALUES BTWN 1800
AND 2400 J/KG AND LIS NEAR -6C. THINKING THESE NUMBERS ARE OVERDONE
DUE TO PROGGED SFC DWPTS TEMPS OF 20C OFF THE NAM SOLUTION. NAM/BTV
4KM INDICATES A WEAK SFC CONVERGENCE BOUNDARY FROM SE FLOW AROUND
SFC HIGH PRES AND DEVELOPING SOUTHWEST FLW AHEAD OF NEXT SFC COLD
FRNT ACROSS OUR CWA ON MONDAY...WHICH COULD PROVIDE ENOUGH LLVL
FORCING TO PRODUCE SHOWERS/STORMS. WILL CONT TO MENTION SCHC TO LOW
CHC POPS ON MONDAY AFTN/EVENING...BUT THINKING DRY AIR ALOFT AND
WARM TEMPS ALOFT WILL LIMIT AREAL COVERAGE/INTENSITY OF
SHOWERS/STORMS. PROGGED 85H TEMPS NEAR 18C ON MONDAY SUPPORT HIGHS
MID/UPPER 80S WITH A FEW READINGS NEAR 90F IN THE WARMER VALLEYS. IN
ADDITION...SFC DWPTS WILL CONT TO CLIMB SEVERAL DEGREES...ADDING TO
THE HUMIDITY LEVELS.
&&
.LONG TERM /TUESDAY THROUGH SATURDAY/...
AS OF 424 AM EDT SATURDAY...FAIRLY ACTIVE WEATHER THROUGH
WEDNESDAY WITH CHANCE OF SHOWERS AND PERHAPS A FEW THUNDERSTORMS.
UPPER LEVEL TROUGH DEVELOPS OVER THE NORTHEAST ON TUESDAY. A SLOW
MOVING COLD FRONT WILL DEPRESS SOUTH THROUGH THE REGION TUESDAY
NIGHT INTO WEDNESDAY. SOME RATHER SIGNIFICANT DIFFERENCES BETWEEN
GFS AND ECMWF REGARDING AMOUNT OF MOISTURE AVAILABLE AND POSITION
OF SHORTWAVE MOVING THROUGH THE UPPER TROUGH DURING THIS PERIOD.
ECMWF THE DRIER OF THE TWO MODELS WITH SHORTWAVE ENERGY PASSING
FURTHER SOUTH. HAVE GONE CLOSE TO A BLEND OF THE TWO...KEEPING
CHANCE SHOWERS WITH SLIGHT CHANCE OF STORMS TUESDAY INTO WEDNESDAY.
GFS WOULD SUGGEST POTENTIAL OF LOCALLY HEAVY RAIN WITH PRECIPITABLE
WATER VALUES 1.5 TO 1.8 INCHES...BUT LACK OF FORCING ON ECMWF MAY
PRECLUDE ANY WIDESPREAD PRECIPITATION.
DRIER WEATHER RETURNS LATER IN THE WEEK. CHANCES FOR SHOWERS
DECREASE LATER WEDNESDAY INTO WEDNESDAY NIGHT AS FRONT DEPRESSES
SOUTH OF THE AREA. UPPER TROUGH DEPARTS BY THURSDAY AND SURFACE
FRONT PUSHES FURTHER SOUTH BEFORE STALLING OUT. THIS ALLOWS FOR HIGH
PRESSURE AND MAINLY DRY CONDITIONS FOR THURSDAY AND FRIDAY.
DISTURBANCE IN FLOW ALOFT COMBINED WITH WARM AIR ADVECTION WILL
BRING CHANCE OF SHOWERS AND STORMS NEXT SATURDAY.
TEMPERATURES WILL BE AROUND NORMAL ON TUESDAY...THEN FALL TO A BIT
BELOW NORMAL WEDNESDAY AND THURSDAY WHEN HIGHS WILL BE IN THE UPPER
70S. SIGNIFICANT WARMING TREND POSSIBLE AS WE HEAD INTO NEXT
WEEKEND.
&&
.AVIATION /20Z SATURDAY THROUGH THURSDAY/...
THROUGH 18Z SUNDAY...MAINLY VFR THROUGH THE PERIOD AS A RIDGE OF
HIGH PRESSURE WILL BE OVER THE REGION. BROKEN DECK OF MID CLOUDS
TONIGHT AS WEAK BOUNDARY DROPS INTO THE AREA. COULD BE AN ISOLATED
SHOWER NORTH...BUT CHANCES TOO LOW FOR ANY INCLUSION IN TAFS AT
THIS TIME. COULD ALSO BE SOME VISIBILITY RESTRICTIONS OVERNIGHT IN
LIGHT FOG OR MIST...MAINLY AT MPV/SLK. BUT GIVEN EXPECTED MID
CLOUD DECK...HAVE CONTINUED WITH PREVIOUS THINKING AND KEPT OUT
ANY MENTION OF FOG. WINDS WILL BE SOUTH TO SOUTHWEST 5-10 KNOTS
THIS AFTERNOON WITH SOME HIGHER GUSTS AT MSS. WINDS LIGHT AND
VARIABLE TONIGHT AND SOUTHWEST LESS THAN 10 KNOTS ON SUNDAY.
OUTLOOK 18Z SUNDAY THROUGH THURSDAY...
18Z SUN-12Z MON...MAINLY VFR EXCEPT FOR EARLY MORNING MVFR/IFR IN
FOG MONDAY...MAINLY MPV/SLK. ISOLATED SHOWERS SUNDAY AFTERNOON.
12Z MON-00Z THU...SCATTERED TO NUMEROUS SHOWERS EACH DAY WITH
MVFR CONDITIONS AT TIMES. ISOLATED THUNDER.
00Z THU-00Z FRI...MAINLY VFR.
&&
.BTV WATCHES/WARNINGS/ADVISORIES...
VT...NONE.
NY...NONE.
&&
$$
SYNOPSIS...TABER
NEAR TERM...TABER
SHORT TERM...TABER
LONG TERM...RJS
AVIATION...RJS
AREA FORECAST DISCUSSION
NWS BURLINGTON VT
328 PM EDT SAT JUL 11 2015
.SYNOPSIS...
A RIDGE OF HIGH PRESSURE BOTH AT THE SURFACE AND ALOFT
WILL CONTINUE TO PROVIDE THE NORTH COUNTRY WITH ABOVE NORMAL
TEMPERATURES AND MAINLY DRY CONDITIONS THROUGH EARLY MONDAY. A FEW
ISOLATED SHOWERS ARE POSSIBLE TONIGHT ACROSS NORTHERN VERMONT AND
AGAIN ON SUNDAY AND MONDAY AFTERNOONS. A COLD FRONT WILL PROVIDE
BETTER CHANCES FOR SHOWERS ON TUESDAY INTO WEDNESDAY...ALONG WITH
COOLER TEMPERATURES.
&&
.NEAR TERM /UNTIL 6 AM SUNDAY MORNING/...
AS OF 330 PM EDT SATURDAY...BIG PICTURE ON WATER VAPOR SHOWS NW
FLW ALOFT WITH BUILDING MID/UPPER LVL RIDGE ACROSS THE OHIO
VALLEY/CENTRAL GREAT LAKES. HAVE NOTED A VERY WEAK 5H VORT WITH SOME
MID LVL MOISTURE NEAR MANIWAKI, QC...WITH GENERAL SOUTHEAST MOVEMENT
TWD OUR NORTHERN CWA BY TONIGHT. THE LATEST GFS AND HRRR MODELS SHOW
VERY WEAK QPF OUTPUT FROM THIS FEATURE...WITH GREATEST CHCS OF A
SHOWER ACROSS NEK OF VT. WL CONTINUE WITH PREVIOUS FCSTER THINKING A
MENTION SCHC TO VERY LOW CHC POPS ACROSS OUR NORTHERN CWA TONIGHT.
ANY QPF WL BE LIGHT <0.10". EXPECTING LOWS MAINLY IN THE 60S WITH
50S IN THE COOLER MTN VALLEYS. HAVE NOTED SFC DWPTS 3 TO 5 DEGREES
WARMER THAN YESTERDAY AT THIS TIME...BUT WITH SOME BL WINDS BTWN 10
AND 15 KNOTS AND NO RAIN IN THE PAST 30 HOURS...WL NOT MENTION FOG
IN FCST AT THIS TIME.
&&
.SHORT TERM /6 AM SUNDAY MORNING THROUGH MONDAY NIGHT/...
AS OF 330 PM EDT SATURDAY...MID/UPPER LVL RIDGE BUILDS ACROSS OUR
CWA ON SUNDAY WITH WARMING TEMPS AND SUBSIDENCE ALOFT.
HOWEVER...ANOTHER VERY WEAK 5H VORT ALONG WITH STRONG SFC HEATING
HELPING TO CREATE SOME INSTABILITY MAY PRODUCE A FEW MORE SHOWERS
ON SUNDAY AFTN. HAVING DIFFICULTIES SEEING MUCH AREAL COVERAGE OR
INTENSITY TO SHOWERS OR STORMS...GIVEN DRY AIR ALOFT AND PROGGED
500MB TEMPS NEAR -10C. IN ADDITION...SOUNDINGS ARE NOT VERY
IMPRESSIVE WITH INSTABILITY PARAMETERS GIVEN WARM TEMPS ALOFT. SO
WILL MENTION JUST ISOLATED CHCS ATTM FOR SUNDAY. GFS QPF FIELDS
SEEM OVERDONE GIVEN POSITION OF RIDGE AXIS DIRECTLY OVERHEAD AND
ASSOCIATED SUBSIDENCE. PROGGED 85H TEMPS WARM ANOTHER DEGREE FROM
SATURDAY...AND WILL SUPPORT HIGHS IN THE LOWER 80S MTN VALLEY
TOWNS TO M/UPPER 80S CHAMPLAIN AND SAINT LAWRENCE VALLEYS.
FORECAST CHALLENGE ON MONDAY WILL BE CHANCES FOR ADDITIONS SHOWERS
AND STORMS ASSOCIATED WITH S/W ENERGY UNDERCUTTING MID/UPPER LVL
RIDGE. GFS CONTS TO BE THE MOST AGGRESSIVE WITH S/W ENERGY WHICH IS
CURRENTLY OVER IOWA AND PRODUCING AREAS OF QPF ACROSS OUR CWA ON
MONDAY AFTN. INSTABILITY PARAMETERS ARE MODEST WITH CAPE VALUES
BETWEEN 400 AND 800 J/KG AND LIS BTWN -2C AND -4C OFF THE
GFS...WHILE THE NAM SHOWS GREATER SFC BASED CAPE VALUES BTWN 1800
AND 2400 J/KG AND LIS NEAR -6C. THINKING THESE NUMBERS ARE OVERDONE
DUE TO PROGGED SFC DWPTS TEMPS OF 20C OFF THE NAM SOLUTION. NAM/BTV
4KM INDICATES A WEAK SFC CONVERGENCE BOUNDARY FROM SE FLOW AROUND
SFC HIGH PRES AND DEVELOPING SOUTHWEST FLW AHEAD OF NEXT SFC COLD
FRNT ACROSS OUR CWA ON MONDAY...WHICH COULD PROVIDE ENOUGH LLVL
FORCING TO PRODUCE SHOWERS/STORMS. WILL CONT TO MENTION SCHC TO LOW
CHC POPS ON MONDAY AFTN/EVENING...BUT THINKING DRY AIR ALOFT AND
WARM TEMPS ALOFT WILL LIMIT AREAL COVERAGE/INTENSITY OF
SHOWERS/STORMS. PROGGED 85H TEMPS NEAR 18C ON MONDAY SUPPORT HIGHS
MID/UPPER 80S WITH A FEW READINGS NEAR 90F IN THE WARMER VALLEYS. IN
ADDITION...SFC DWPTS WILL CONT TO CLIMB SEVERAL DEGREES...ADDING TO
THE HUMIDITY LEVELS.
&&
.LONG TERM /TUESDAY THROUGH SATURDAY/...
AS OF 424 AM EDT SATURDAY...RATHER UNSETTLED AT THE BEGINNING OF
THE LONG TERM PERIOD FROM MONDAY NIGHT THROUGH WEDNESDAY...WITH A
CHANCE FOR SHOWERS AND THUNDERSTORMS. A SLOW MOVING COLD FRONT
WILL MOVE SLOWLY SOUTH THROUGH THE REGION TUESDAY NIGHT WITH
SHOWERS LINGERING INTO WEDNESDAY. A RIDGE OF HIGH PRESSURE WILL
BUILD SOUTHEAST FROM CANADA AND THE GREAT LAKES ON THURSDAY AND
WILL REMAIN OVER THE REGION THROUGH FRIDAY...WITH FAIR AND DRY
WEATHER EXPECTED THURSDAY AND FRIDAY.
&&
.AVIATION /20Z SATURDAY THROUGH THURSDAY/...
THROUGH 18Z SUNDAY...MAINLY VFR THROUGH THE PERIOD AS A RIDGE OF
HIGH PRESSURE WILL BE OVER THE REGION. BROKEN DECK OF MID CLOUDS
TONIGHT AS WEAK BOUNDARY DROPS INTO THE AREA. COULD BE AN ISOLATED
SHOWER NORTH...BUT CHANCES TOO LOW FOR ANY INCLUSION IN TAFS AT
THIS TIME. COULD ALSO BE SOME VISIBILITY RESTRICTIONS OVERNIGHT IN
LIGHT FOG OR MIST...MAINLY AT MPV/SLK. BUT GIVEN EXPECTED MID
CLOUD DECK...HAVE CONTINUED WITH PREVIOUS THINKING AND KEPT OUT
ANY MENTION OF FOG. WINDS WILL BE SOUTH TO SOUTHWEST 5-10 KNOTS
THIS AFTERNOON WITH SOME HIGHER GUSTS AT MSS. WINDS LIGHT AND
VARIABLE TONIGHT AND SOUTHWEST LESS THAN 10 KNOTS ON SUNDAY.
OUTLOOK 18Z SUNDAY THROUGH THURSDAY...
18Z SUN-12Z MON...MAINLY VFR EXCEPT FOR EARLY MORNING MVFR/IFR IN
FOG MONDAY...MAINLY MPV/SLK. ISOLATED SHOWERS SUNDAY AFTERNOON.
12Z MON-00Z THU...SCATTERED TO NUMEROUS SHOWERS EACH DAY WITH
MVFR CONDITIONS AT TIMES. ISOLATED THUNDER.
00Z THU-00Z FRI...MAINLY VFR.
&&
.BTV WATCHES/WARNINGS/ADVISORIES...
VT...NONE.
NY...NONE.
&&
$$
SYNOPSIS...TABER
NEAR TERM...TABER
SHORT TERM...TABER
LONG TERM...WGH
AVIATION...RJS
AREA FORECAST DISCUSSION
NWS RALEIGH NC
340 PM EDT SAT JUL 11 2015
.SYNOPSIS...A WEAK AREA OF LOW PRESSURE WILL DROP SOUTHEAST FROM
VIRGINIA INTO EASTERN NORTH CAROLINA THIS AFTERNOON AND THEN MOVE
OFFSHORE TONIGHT. THE TRAILING COLD FRONT WILL MOVE THROUGH THE AREA
THIS EVENING AND TONIGHT. WEAK SURFACE HIGH PRESSURE WILL EXTEND
INTO THE AREA ON SUNDAY. AN INCREASINGLY ACTIVE NORTHWEST FLOW ALOFT
WILL DEVELOP DOWNSTREAM ACROSS THE CAROLINAS AND MID ATLANTIC EARLY
NEXT WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 320 PM SATURDAY...
A MID-LEVEL DISTURBANCE DIVING ACROSS SOUTHEAST VA HAS TRIGGERED
NUMEROUS STORMS OVER NORTHEAST NC IN A STRONG INSTABILITY AXIS
NORTHEAST OF A WEAK SURFACE LOW OVER THE COASTAL PLAIN. THE
CONVECTION HAS BEEN MORE SCATTERED AND LESS INTENSE THE NORTHERN
COASTAL PIEDMONT/COASTAL PLAIN....WITH REALLY JUST SHOWERS NORTH AND
EAST OF THE TRIANGLE. THE CONVECTION WILL HAVE THE OPPORTUNITY TO
INTENSIFY AS IT MOVES EAST OF I-95...BUT RADAR TRENDS AND RECENT
HRRR RUNS SUGGEST THE DEEPEST CONVECTION WILL REMAIN EAST OF THE RAH
CWA AND WITHIN THE ONGOING SEVERE TSTORM WATCH. TO THE SOUTH AND
WEST...THE CU FIELD HAS BEEN EXPANDING BUT NO MORE THAN A STRAY
SHOWER IS EXPECTED THROUGH THIS EVENING.
TONIGHT...THE AFOREMENTIONED SURFACE LOW WILL DRIFT EAST OFFSHORE
AND ALLOW A SECONDARY...EFFECTIVE FRONT TO OUR NORTH TO SLIP SOUTH
THROUGH THE AREA. NORTH-NORTHEASTERLY WIND WILL ADVECT SOME LOW-
LEVEL MOISTURE CURRENTLY OVER VA... WHERE CEILINGS ARE IN THE 1000-
2000FT RANGE...SOUTH ACROSS THE COASTAL PLAIN. SREF PROBABILITIES
SHOW MORE POTENTIAL FOR STRATUS ACROSS THE CENTRAL PIEDMONT...BUT
NAM/GFS AND RAP SOUNDINGS SHOW BETTER EAST OF US HWY 1. LOWS IN THE
MID/UPPER 60S NORTH AND WEST TO LOWER SOUTH AND EAST 70S.
&&
.SHORT TERM /SUNDAY AND SUNDAY NIGHT/...
AS OF 340 PM SATURDAY...
WITH THE COLD FRONT SETTLING ALONG THE SOUTHEAST COAST THE WEAK
SURFACE LOW MEANDERING OFF THE NC/VA COAST...A SLIGHTLY COOLER AND
DRIER NORTHERLY FLOW WILL PREVAIL DURING THE DAY. THICKNESSES AROUND
1400M SUNDAY MORNING ARE ABOUT 10M BELOW NORMAL AND HIGHS SHOULD BE
A COUPLE DEGREES BELOW NORMAL IN THE 87-91 RANGE. A WEAK
DISTURBANCE AND/OR OUTFLOW FROM UPSTREAM CONVECTION IS FORECAST TO
CROSS THE MOUNTAINS SUNDAY EVENING...WHICH MAY TRIGGER SOME SOME
SHOWERS LATE IN THE EVENING OR EVEN OVERNIGHT. HOWEVER...THE MAIN
SHORTWAVE WILL PASS WELL TO OUR NORTH AND ITS STILL UNCERTAIN HOW
MUCH LOW-LEVEL MOISTURE RECOVERY THERE WILL BE TO AID IN ANY
ADDITIONAL MUCAPE OVERNIGHT. WILL INCLUDE A CHANCE POP WEST TO
SLIGHT CHANCE POP EAST...FOLLOWING A GENERAL CONSENSUS OF GUIDANCE.
LOWS IN THE UPPER 60S TO AROUND 70.
&&
.LONG TERM /MONDAY THROUGH SATURDAY/...
AS OF 310 PM SATURDAY...
THE MID LEVEL RIDGE IS PROGGED TO BE SITUATED OVER TX/LA...WITH
TROUGHS OVER EACH COAST...THROUGH THE MID TO END OF NEXT WEEK. THIS
WILL RESULT IN NORTHWEST FLOW OVER THE REGION...LEADING TO POTENTIAL
REMNANT MCS/MCVS TRACKING OVERHEAD AND HENCE SHOWERS/STORMS. THIS
TYPE OF PATTERN IS HARD TO NAIL DOWN PRECISE TIMING/LOCATION OF ANY
CONVECTION...WITH AT LEAST DIURNAL TYPE POPS EACH DAY. AS OF NOW...
TUESDAY LOOKS TO BE THE BEST CHANCE OF SIGNIFICANT COVERAGE AS
MODELS INDICATE A FAIRLY ROBUST SHORTWAVE DIGGING INTO THE AREA. IN
ADDITION BETTER SEVERE WEATHER PARAMETERS ARE PROGGED OVER THE
REGION DURING THIS TIME FRAME AS DEEP LAYER SHEAR ON THE ORDER OF 35
KNOTS IS EXPECTED AND MODELS INDICATE A MODIFIED EML ADVECTING INTO
THE AREA. HOWEVER...CONFIDENCE IS STILL NOT VERY HIGH GIVEN THE FACT
THAT THE ECMWF IS STILL 12-24 HOURS BEHIND IN RELATION TO THE
ARRIVAL OF THE AFOREMENTIONED ROBUST SHORTWAVE. NEVERTHELESS...WILL
SHOW THE RELATIVE HIGHEST POPS ON TUESDAY/WEDNESDAY FOR THIS PERIOD
WITH AT LEAST CLIMO POPS FOR THE REMAINDER OF THE PERIOD. THE MID
LEVEL FLOW SHOULD FLATTEN OUT SOME BY THE END OF THE WEEK AS THE MID
LEVEL RIDGE STARTS TO EXPAND EASTWARD ONCE AGAIN. TEMPS SHOULD BE
SLIGHTLY ABOVE NORMAL FOR MOST OF THE PERIOD...WITH HIGHS IN THE
LOW/MID 90S AND LOWS IN THE LOW/MID 70S...BUT THIS COULD BE ALTERED
BY HIGHER CLOUD/PRECIP COVERAGE.
&&
.AVIATION /18Z SATURDAY THROUGH WEDNESDAY/...
AS OF 210 PM SATURDAY...
SCATTERED SHOWERS HAVE DEVELOP TO THE NORTH OF KRDU AND KRWI IN
RESPONSE TO STRONG HEATING AND AN UPPER LEVEL DISTURBANCES MOVING
NORTHWEST TO SOUTHEAST ACROSS THE AREA. EXPECT THESE SHOWERS TO
INCREASE AND COVERAGE AND ALSO IN INTENSITY...WITH THE BEST CHANCE
OF A THUNDERSTORM AT KRWI BETWEEN 18Z AND 21. MEANWHILE...WINDS
WILL BE OUT OF THE NORTH-NORTHWEST THIS AFTERNOON...GUSTING TO 15-
18KT SPORADICALLY...THEN TURNING TO NORTHEASTERLY THIS EVENING AS A
WAVE OF LOW PRESSURE MOVES FROM THE COASTAL PLAIN TOWARD THE OUTER
BANKS AND A COLD FRONT SLIPS THROUGH THE AREA. THIS NORTHEASTERLY
FLOW SHOULD ADVECT IN LOW-LEVEL MOISTURE AND CAUSE STRATUS TO FORM
LATE TONIGHT...MAINLY EAST OF KRDU. SOME GUIDANCE INDICATES IFR
STRATUS AND OTHERS INDICATE AS LOW AS LIFR. CONFIDENCE IN LIFR
CONDITIONS ISN`T VERY HIGH AT THE MOMENT...BUT KRWI WOULD LIKELY HAVE
THE BEST CHANCE OF THE POOREST CONDITIONS.
DRIER AIR AND LESS INSTABILITY WILL LEAD TO FEW STORMS ON
SUNDAY...IF ANY...AND VFR CONDITIONS.
LOOKING AHEAD: PREDOMINATELY VFR CONDITIONS ARE EXPECTED UNTIL
MONDAY...WHEN A SERIES OF DISTURBANCES APPROACHING FROM THE
NORTHWEST WILL RESULT IN A PERIOD OF ACTIVE WEATHER THROUGH MIDWEEK.
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...BLAES
NEAR TERM...22
SHORT TERM...22
LONG TERM...KRD
AVIATION...22
AREA FORECAST DISCUSSION
NWS RALEIGH NC
320 PM EDT SAT JUL 11 2015
.SYNOPSIS...A WEAK AREA OF LOW PRESSURE WILL DROP SOUTHEAST FROM
VIRGINIA INTO EASTERN NORTH CAROLINA THIS AFTERNOON AND THEN MOVE
OFFSHORE TONIGHT. THE TRAILING COLD FRONT WILL MOVE THROUGH THE AREA
THIS EVENING AND TONIGHT. WEAK SURFACE HIGH PRESSURE WILL EXTEND
INTO THE AREA ON SUNDAY. AN INCREASINGLY ACTIVE NORTHWEST FLOW ALOFT
WILL DEVELOP DOWNSTREAM ACROSS THE CAROLINAS AND MID ATLANTIC EARLY
NEXT WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 320 PM SATURDAY...
A MID-LEVEL DISTURBANCE DIVING ACROSS SOUTHEAST VA HAS TRIGGERED
NUMEROUS STORMS OVER NORTHEAST NC IN A STRONG INSTABILITY AXIS
NORTHEAST OF A WEAK SURFACE LOW OVER THE COASTAL PLAIN. THE
CONVECTION HAS BEEN MORE SCATTERED AND LESS INTENSE THE NORTHERN
COASTAL PIEDMONT/COASTAL PLAIN....WITH REALLY JUST SHOWERS NORTH AND
EAST OF THE TRIANGLE. THE CONVECTION WILL HAVE THE OPPORTUNITY TO
INTENSIFY AS IT MOVES EAST OF I-95...BUT RADAR TRENDS AND RECENT
HRRR RUNS SUGGEST THE DEEPEST CONVECTION WILL REMAIN EAST OF THE RAH
CWA AND WITHIN THE ONGOING SEVERE TSTORM WATCH. TO THE SOUTH AND
WEST...THE CU FIELD HAS BEEN EXPANDING BUT NO MORE THAN A STRAY
SHOWER IS EXPECTED THROUGH THIS EVENING.
TONIGHT...THE AFOREMENTIONED SURFACE LOW WILL DRIFT EAST OFFSHORE
AND ALLOW A SECONDARY...EFFECTIVE FRONT TO OUR NORTH TO SLIP SOUTH
THROUGH THE AREA. NORTH-NORTHEASTERLY WIND WILL ADVECT SOME LOW-
LEVEL MOISTURE CURRENTLY OVER VA... WHERE CEILINGS ARE IN THE 1000-
2000FT RANGE...SOUTH ACROSS THE COASTAL PLAIN. SREF PROBABILITIES
SHOW MORE POTENTIAL FOR STRATUS ACROSS THE CENTRAL PIEDMONT...BUT
NAM/GFS AND RAP SOUNDINGS SHOW BETTER EAST OF US HWY 1. LOWS IN THE
MID/UPPER 60S NORTH AND WEST TO LOWER SOUTH AND EAST 70S.
&&
.SHORT TERM /SUNDAY AND SUNDAY NIGHT/...
AS OF 350 AM FRIDAY...
SUNDAY INTO SUNDAY NIGHT: WITH THE WAVY FRONTAL ZONE DRAPED ALONG
THE SOUTHEAST COAST...WEAK SURFACE RIDGING WITH A RESERVOIR OF LOW-
LEVEL DRY/LOWER THETA-E AIR WILL BE IN PLACE ACROSS CENTRAL NC ON
SUNDAY...WHICH WILL MAKE FOR COMFORTABLE HUMIDITY LEVELS BY JULY
STANDARDS WITH SEASONABLE DAYTIME HIGHS IN THE UPPER 80S TO LOWER
90S.
THE POTENTIAL WILL BE THERE FOR SOME ISOLATED SHOWERS ACROSS THE AREA
ON SUNDAY AND EVEN SUNDAY NIGHT...ESPECIALLY ACROSS THE NW PIEDMONT
AS FCST MODELS DIFFER WITH THE TIMING OF THE INDIVIDUAL WEAK
SHORTWAVE DISTURBANCES EMBEDDED IN THE NWLY FLOW...ON THE
NORTHEASTERN FLANKS OF THE STRONG MID-LEVEL ANTICYCLONE CENTERED
ACROSS THE SOUTHERN PLAINS. THUNDER MAY BE HARD TO COME BY AS
INSTABILITY IS LIMITED OWING TO THE LOW-LEVEL DRY AIR IN PLACE AND
WARM TEMPERATURES ALOFT. LOWS IN THE MID 60S TO LOWER 70S.
&&
.LONG TERM /MONDAY THROUGH SATURDAY/...
AS OF 310 PM SATURDAY...
THE MID LEVEL RIDGE IS PROGGED TO BE SITUATED OVER TX/LA...WITH
TROUGHS OVER EACH COAST...THROUGH THE MID TO END OF NEXT WEEK. THIS
WILL RESULT IN NORTHWEST FLOW OVER THE REGION...LEADING TO POTENTIAL
REMNANT MCS/MCVS TRACKING OVERHEAD AND HENCE SHOWERS/STORMS. THIS
TYPE OF PATTERN IS HARD TO NAIL DOWN PRECISE TIMING/LOCATION OF ANY
CONVECTION...WITH AT LEAST DIURNAL TYPE POPS EACH DAY. AS OF NOW...
TUESDAY LOOKS TO BE THE BEST CHANCE OF SIGNIFICANT COVERAGE AS
MODELS INDICATE A FAIRLY ROBUST SHORTWAVE DIGGING INTO THE AREA. IN
ADDITION BETTER SEVERE WEATHER PARAMETERS ARE PROGGED OVER THE
REGION DURING THIS TIME FRAME AS DEEP LAYER SHEAR ON THE ORDER OF 35
KNOTS IS EXPECTED AND MODELS INDICATE A MODIFIED EML ADVECTING INTO
THE AREA. HOWEVER...CONFIDENCE IS STILL NOT VERY HIGH GIVEN THE FACT
THAT THE ECMWF IS STILL 12-24 HOURS BEHIND IN RELATION TO THE
ARRIVAL OF THE AFOREMENTIONED ROBUST SHORTWAVE. NEVERTHELESS...WILL
SHOW THE RELATIVE HIGHEST POPS ON TUESDAY/WEDNESDAY FOR THIS PERIOD
WITH AT LEAST CLIMO POPS FOR THE REMAINDER OF THE PERIOD. THE MID
LEVEL FLOW SHOULD FLATTEN OUT SOME BY THE END OF THE WEEK AS THE MID
LEVEL RIDGE STARTS TO EXPAND EASTWARD ONCE AGAIN. TEMPS SHOULD BE
SLIGHTLY ABOVE NORMAL FOR MOST OF THE PERIOD...WITH HIGHS IN THE
LOW/MID 90S AND LOWS IN THE LOW/MID 70S...BUT THIS COULD BE ALTERED
BY HIGHER CLOUD/PRECIP COVERAGE.
&&
.AVIATION /18Z SATURDAY THROUGH WEDNESDAY/...
AS OF 210 PM SATURDAY...
SCATTERED SHOWERS HAVE DEVELOP TO THE NORTH OF KRDU AND KRWI IN
RESPONSE TO STRONG HEATING AND AN UPPER LEVEL DISTURBANCES MOVING
NORTHWEST TO SOUTHEAST ACROSS THE AREA. EXPECT THESE SHOWERS TO
INCREASE AND COVERAGE AND ALSO IN INTENSITY...WITH THE BEST CHANCE
OF A THUNDERSTORM AT KRWI BETWEEN 18Z AND 21. MEANWHILE...WINDS
WILL BE OUT OF THE NORTH-NORTHWEST THIS AFTERNOON...GUSTING TO 15-
18KT SPORADICALLY...THEN TURNING TO NORTHEASTERLY THIS EVENING AS A
WAVE OF LOW PRESSURE MOVES FROM THE COASTAL PLAIN TOWARD THE OUTER
BANKS AND A COLD FRONT SLIPS THROUGH THE AREA. THIS NORTHEASTERLY
FLOW SHOULD ADVECT IN LOW-LEVEL MOISTURE AND CAUSE STRATUS TO FORM
LATE TONIGHT...MAINLY EAST OF KRDU. SOME GUIDANCE INDICATES IFR
STRATUS AND OTHERS INDICATE AS LOW AS LIFR. CONFIDENCE IN LIFR
CONDITIONS ISN`T VERY HIGH AT THE MOMENT...BUT KRWI WOULD LIKELY HAVE
THE BEST CHANCE OF THE POOREST CONDITIONS.
DRIER AIR AND LESS INSTABILITY WILL LEAD TO FEW STORMS ON
SUNDAY...IF ANY...AND VFR CONDITIONS.
LOOKING AHEAD: PREDOMINATELY VFR CONDITIONS ARE EXPECTED UNTIL
MONDAY...WHEN A SERIES OF DISTURBANCES APPROACHING FROM THE
NORTHWEST WILL RESULT IN A PERIOD OF ACTIVE WEATHER THROUGH MIDWEEK.
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...BLAES
NEAR TERM...22
SHORT TERM...CBL
LONG TERM...KRD
AVIATION...22
AREA FORECAST DISCUSSION
NWS GRAND FORKS ND
939 PM CDT SUN JUL 12 2015
.UPDATE...
ISSUED AT 940 PM CDT SUN JUL 12 2015
THE LATEST HRRR BRINGS THE CURRENT CONVECTION IN THE DEVILS LAKE
BASIN EAST INTO THE VALLEY OVER THE NEXT FEW HOURS.
THEREAFTER...THERE SHOULD BE A WEAKENING TRENDS AFTER 6Z AS
INSTABILITY SLOWLY DECREASES. THERE WILL BE A WESTERLY 850MB LLJ
AROUND 30KT...THAT COULD SUSTAIN SOME STRONGER STORMS OVERNIGHT.
MOST OF THE FORECAST AREA HAS BEEN WORKED OVER BY CONVECTION...SO
NOT EXPECTING MUCH MORE SEVERE WEATHER...BUT SOME STRONG STORMS
POSSIBLE THROUGH 6Z OR SO. THE CURRENT WATCH WILL EXPIRE AT 10 PM
AND NOT EXPECTING ANOTHER WATCH ATTM.
&&
.SHORT TERM...(THIS EVENING THROUGH MONDAY NIGHT)
ISSUED AT 230 PM CDT SUN JUL 12 2015
SHORT TERM CAM MODEL GUIDANCE CONTINUES IN GOOD AGREEMENT WITH 2
MAIN AREAS OF CONVECTION THIS EVENING. THE FIRST INITIATES VCNTY
DEVILS LAKE BASIN WITH ANOTHER STRONGER AREA OVER THE SE FA THEN
PROPAGATING E-SE THROUGH THE EVENING. CAP HOLDING SO FAR BUT
SUFFICE TO SAY ALL CONVECTIVE PARAMETERS IN PLACE FOR POTENTIALLY
SIGNIFICANT SEVERE WX EVENT. BASED ON MODEL GUIDANCE CONVECTION
SHOULD BE CLOSE TO EXITING THE FA BY SUNSET.
REMNANTS OF SOUTH CENTRAL CANADIAN MID LEVEL TROUGH WILL DROP
THROUGH THE FA TOMORROW SO WILL MAINTAIN POPS HOWEVER AIRMASS NOT
NEARLY AS UNSTABLE. EXCEPT FOR THE SW FA TEMPERATURES WILL BE
CLOSER TO AVERAGE.
ANY REMAINING CONVECTION WILL DISSIPATE AT SUNSET. WITH DEWPOINTS
CONTINUING IN THE 60S EXPECT SIMILAR MINIMUM TEMPERATURES.
.LONG TERM...(TUESDAY THROUGH SUNDAY)
ISSUED AT 230 PM CDT SUN JUL 12 2015
MID LEVEL RIDGE BUILDS INTO MIDWEEK. RIPPLES OF ENERGY DROPPING
DOWN FRONT OF THE RIDGE WILL CONTINUE TO BRING CHANCES FOR TSRA TO
THE REGION WITH SEASONAL TEMPERATURES.
MODELS IN GENERAL AGREEMENT FOR THIS FORECAST PERIOD...THUS WENT
WITH A BLENDED SOLN ATTM. LOOKING FOR A BIT OF A CHANGE TO THE UPPER
LEVEL PATTERN AS THE RIDGE OVER THE UPPER MIDWEST WEAKENS AND
BECOMES MORE ZONAL. EXPECT TO SEE A FEW MORE IMPULSES MOVING THROUGH
THE FLOW...TRIGGERING CHANCES FOR SHOWERS AND THUNDERSTORMS EACH
DAY. HOWEVER...LITTLE CHANGE IS EXPECTED TO TEMPERATURES...WITH
HIGHS MAINLY IN THE LOW 80S AND LOWS AROUND 60.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z MONDAY EVENING)
ISSUED AT 653 PM CDT SUN JUL 12 2015
CAUTIOUSLY LEFT T MENTION OUT OF DVL/GFK/FAR AS MOST CONVECTION
SHIFTING INTO MN. WITH LACK OF LOW LEVEL JET SHOULD SEE WEAKENING
IN THE NEXT FEW HOURS. OTHERWISE PRIMARILY LOOKING AT VFR CONDITIONS
THROUGH THE PERIOD.
&&
.FGF WATCHES/WARNINGS/ADVISORIES...
ND...NONE.
MN...NONE.
&&
$$
UPDATE...DK
SHORT TERM...VOELKER
LONG TERM...HOPKINS/VOELKER
AVIATION...VOELKER
AREA FORECAST DISCUSSION
NWS BISMARCK ND
1212 AM CDT SAT JUL 11 2015
.UPDATE...
ISSUED AT 1212 AM CDT SAT JUL 11 2015
NO MAJOR CHANGES MADE TO THE FORECAST.
UPDATE ISSUED AT 933 PM CDT FRI JUL 10 2015
NO SIGNIFICANT CHANGES WITH THIS FORECAST UPDATE AS ANY
CONVECTION FOR THE REMAINDER OF THE NIGHT WILL BE ISOLATED AT BEST
AS THE LOW LEVEL JET INCREASES UNDER SOUTHWEST FLOW ALOFT. THIS IS
SUPPORTED BY THE 00 UTC NAM AND 00-01 UTC HRRR ITERATIONS.
UPDATE ISSUED AT 733 PM CDT FRI JUL 10 2015
WHILE ISOLATED CELLS HAVE INITIATED ACROSS SOUTH CENTRAL NORTH
DAKOTA THIS EVENING...WEAK LAPSE RATES AND SHEAR HAVE LEAD TO VERY
QUICK DISSIPATION OF THESE SHOWERS/STORMS. THE HRRR THUS FAR THIS
EVENING FROM RUN TO RUN HAS OVER DEVELOPED CONVECTION ACROSS THE
DAKOTAS GIVEN THE HIGH CAPE/LOW CIN ENVIRONMENT. THUS...FAVORED
THE 18 UTC NAM AND 15 UTC SREF WHOSE QPF FIELDS ARE CLOSET TO
RADAR TRENDS THROUGH 00 UTC. DO EXPECT AN ISOLATED THUNDERSTORM
THREAT TO CONTINUE THROUGH THE NIGHT AS THE LOW LEVEL JET
INCREASES UNDER SOUTHWEST FLOW ALOFT. HOWEVER...CONTINUED WEAK
SHEAR PRECLUDES A SEVERE THREAT.
UPDATE ISSUED AT 457 PM CDT FRI JUL 10 2015
BASED ON RADAR TRENDS THROUGH 2150 UTC OF ISOLATED TO SCATTERED
THUNDERSTORMS DEVELOPING ACROSS NORTH CENTRAL SOUTH DAKOTA AND A
TIME LAGGED ENSEMBLE OF THE 18-20 UTC HRRR RUNS...INTRODUCED POPS
TO THE FAR SOUTH CENTRAL AND JAMES RIVER VALLEY FOR LATE THIS
AFTERNOON AND EARLY EVENING.
&&
.SHORT TERM...(THIS EVENING THROUGH SATURDAY)
ISSUED AT 224 PM CDT FRI JUL 10 2015
CURRENT SURFACE ANALYSIS PLACES LOW OVER CENTRAL MONTANA WITH
TROUGH OVER SOUTHEAST MONTANA INTO NORTHEAST WYOMING. UPPER LEVEL
ANALYSIS PLACES BROAD UPPER LOW NEAR THE NORTHERN GREAT BASIN WITH
A VARIETY OF WEAK VORTICES WORKING AROUND THE SYSTEM. OVER OUR
AREA...SHORT WAVE LIFTING THROUGH SOUTHWESTERLY FLOW IS STARTING
TO PRODUCE SOME LIGHT CONVECTION OVER SOUTHEAST MONTANA INTO
NORTHERN WYOMING.
FOR THE REST OF THIS AFTERNOON INTO TONIGHT...AFOREMENTIONED SHORT
WAVE WILL CONTINUE TO LIFT TOWARDS THE AREA...WITH SOME
THUNDERSTORMS POSSIBLY DEVELOPING TOWARDS LATE AFTERNOON OVER THE
SOUTHWEST. WAVE WILL CONTINUE TO LIFT OVER THE AREA...FOLLOWED BY
A VARIETY OF ADDITIONAL WEAK SHORT WAVES...THROUGH TONIGHT. MODEST
INSTABILITY REMAINS IN PLACE BUT LITTLE TO NO SHEAR IS AVAILABLE
SO EXPECT STORMS OVERALL TO REMAIN TAME AND RATHER PULSE.
ON SATURDAY...SURFACE LOW LIFTS THROUGH NORTHEAST MONTANA DRAWING
PLENTY OF MOISTURE AHEAD OF IT OVER MUCH OF NORTH DAKOTA. THE
EXCEPTION WILL BE OVER THE SOUTHWEST WHERE A DRYLINE WILL SETUP
WITH FALLING DEWPOINTS AND SOUTHWESTERLY WINDS. TIMING OF
CONVECTION DEVELOPING WILL BE TRICKY GIVEN THE VARIETY OF SHORT
WAVES LIFTING THROUGH THE AREA. INSTABILITY INCREASES QUITE A BIT
WITH THE INCREASING MOISTURE WHICH WILL COMBINE WITH MODEST SHEAR
TO BRING A MARGINAL SEVERE THREAT OVER CENTRAL INTO NORTHWESTERN
NORTH DAKOTA. LARGE HAIL WILL BE THE MAIN THREAT.
.LONG TERM...(SATURDAY NIGHT THROUGH FRIDAY)
ISSUED AT 224 PM CDT FRI JUL 10 2015
THE LONG TERM WILL REMAIN ACTIVE SATURDAY THROUGH THE NEXT WEEK.
SOUTHWEST FLOW ALOFT OVER THE WESTERN US WILL REMAIN OVER THE
NEXT WEEK. THIS WILL PUT NORTH DAKOTA IN A FAVORABLE POSITION TO
RECEIVE MANY UPPER LEVEL SHORT WAVES. ONE SUCH UPPER LOW IS
EXPECTED TO REACH THE NORTHERN PLAINS SATURDAY.
WARM...MOIST AIR WILL SURGE NORTH AHEAD OF THIS WAVE. A RATHER
WARM AND MUGGY SATURDAY/SUNDAY IS EXPECTED. MODELS ARE INDICATING
VERY HIGH CAPE VALUES BUT LITTLE TO NO SHEAR. WITH VERY HIGH
MOISTURE CONTENT THROUGHOUT THE ATMOSPHERE...VERY HEAVY RAIN IS
POSSIBLE WITH ANY THUNDERSTORMS THAT DEVELOP. THE LATEST SPC
SEVERE OUTLOOKS PLACE A MARGINAL THREAT FOR SATURDAY. MOST OF THE
THUNDERSTORM ACTIVITY IS EXPECTED NORTH SUNDAY AND MONDAY.
BY WEDNEDAY AND THURSDAY ANOTHER WAVE IS EXPECTED TO MOVE THROUGH
AS A UPPER LEVEL RIDGE ACROSS THE SOUTH CENTRAL CONUS MOVES EAST.
AT THIS TIME THE GFS/ECMWF INDICATE SCATTERED THUNDERSTORMS ARE
POSSIBLE ACROSS ALL OF WESTERN AND CENTRAL NORTH DAKOTA AS THE
TRACK OF THIS LOW SHOULD BE FURTHER SOUTH THAN THIS WEEKEND`S.
TEMPERATURES SHOULD GENERALLY RANGE FROM THE MID 80S TO LOW 90S
THROUGH THE NEXT WEEK.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT)
ISSUED AT 1212 AM CDT SAT JUL 11 2015
VFR CONDITIONS AND CHANCES FOR ISOLATED THUNDERSTORMS ARE
EXPECTED THROUGH THE TAF PERIOD.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...AC
SHORT TERM...JJS
LONG TERM...AJ
AVIATION...AC
AREA FORECAST DISCUSSION
NWS CHARLESTON WV
755 PM EDT SUN JUL 12 2015
.SYNOPSIS...
UPPER LEVEL DISTURBANCES WILL CROSS THE AREA IN NORTHWEST FLOW
THRU NEXT WEEK...KEEPING UNSETTLED CONDITIONS IN PLACE. AN UPPER
LEVEL RIDGE MAY DEVELOP BY THE END OF NEXT WEEKEND.
&&
.NEAR TERM /THROUGH MONDAY/...
800 PM UPDATE...
INCREASED POPS TONIGHT FROM THE C LOWLANDS AND ESPECIALLY INTO THE
N LOWLANDS/MTNS. A WEAK LOW PRESSURE SYS OVER OH WILL DRIFT SE
INTO THE AREA OVERNIGHT. THIS COMBINED WITH SOME MID LEVEL LIFT
OVER THE AREA SHOULD ALLOW SHRA INCREASE IN COVERAGE THIS AFTER
MIDNIGHT. AS THIS SYS SPIRALS INTO THE AREA...EXPECT LOW CIGS TO
DEVELOP ALONG WITH PATCHY FG.
PREVIOUS DISCUSSION BELOW...
LATEST SATELLITE IMAGERY DEPICTS A RATHER CHAOTIC IMAGE OVER THE
MIDDLE ATLANTIC STATES THIS AFTERNOON...WITH SEVERAL FEATURES OF
NOTE. ACROSS CENTRAL AND EASTERN OHIO THERE IS A FAIRLY WELL
DEFINED SHORTWAVE KICKING OFF SHOWER ACTIVITY ACROSS NORTHEASTERN
OHIO. SKIES HAVE STARTED TO CLEAR SOME ACROSS CENTRAL AND EASTERN
KY...IN THE WAKE OF MCS WHICH MOVED THROUGH THIS MORNING. SEVERAL
OUTFLOW BOUNDARIES CAN BE SEEN IN EASTERN TN AND SOUTHERN KY AS
WELL. THESE HELPING TO KICK OFF CONVECTION. ACROSS WEST VIRGINIA A
SOLID MID DECK OF BLOW CLOUDS HAVE IMPEDED DAYTIME HEATING. THUS
THERE IS A LACK OF CONVECTION INITIATION SO FAR. HOWEVER...BL
HEATING ACROSS THE ELEVATED TERRAIN ALLOWING SOME CU TO FORM.
LATEST SHORT TERM MODELS HAVE BEEN SLOW TO CATCH ON WITH ALL OF
THESE SMALLER SCALE FEATURES. HOWEVER...LATEST RUNS SEEM TO SHOW A
TREND THAT PRECIPITATION SHOULD REMAIN SUPPRESSED FOR THE VERY NEAR
TERM WITH THE RUC AND HRRR IN GENERAL AGREEMENT. AS SHORTWAVE TRACKS
ACROSS THE NORTHERN TIER THIS EVENING...RAMPS POPS BACK UP. FOR
MONDAY...BROAD BUSHED POPS WITH AN EYE ON FEATURES THAT MAY TRACK
ACROSS IN NORTHWEST FLOW.
&&
.SHORT TERM /MONDAY NIGHT THROUGH TUESDAY NIGHT/...
THE GFS AND ECMWF MODELS ARE IN BETTER AGREEMENT WITH AN H500
SHORTWAVE UNDER NORTHWEST FLOW CROSSING THE AREA MONDAY NIGHT. THE
NAM LOOKS ABOUT 6-12 HOURS SLOWER BRINGING MOST OF THE ENERGY BY 12Z
TUESDAY. PREFER THE CONSENSUS FROM GFS/ECMWF. THEREFORE...EXPECT
THIS SHORTWAVE TO BRING GOOD CHANCES FOR SHOWERS OR THUNDERSTORMS...
SOME WITH PERIODS OF HEAVY RAIN INTO EARLY TUESDAY.
MODELS ARE IN AGREEMENT WITH A STRONGER TROUGH/LOW PRESSURE SYSTEM
TO DROP FROM THE GREAT LAKES REGION...SOUTHEAST ACROSS PA AND
PORTIONS OF NORTHERN WV TUESDAY NIGHT. ADDITIONAL ROUNDS FOR SHOWERS
AND THUNDERSTORMS WITH HEAVY RAIN WILL BE POSSIBLE. HAVE CODED
LIKELY POPS FOR BOTH DAYS WITH EACH SYSTEM.
CONCERNS FOR FLOODING CONTINUES DURING THIS PERIOD...AND WILL
CONTINUE MENTION IN THE HAZARDOUS WEATHER OUTLOOK. TEMPERATURES WILL
CONTINUE TO BE MODERATE WITH CLOUDS AND SHOWERS...BUT ALSO REMAINING
QUITE HUMID. MINOR CHANGES MADE TO PREVIOUS TEMPERATURES.
&&
.LONG TERM /WEDNESDAY THROUGH SUNDAY/...
FOR WEDNESDAY...THE AREA WILL STILL BE UNDER THE INFLUENCE OF A
BROAD UPPER LEVEL TROUGH AND NORTHWEST FLOW...KEEPING THE AREA UNDER
CHANCES FOR ADDITIONAL SHOWERS AND THUNDERSTORMS LESS NUMEROUS THAN
THE PREVIOUS DAYS...AT LEAST THROUGH WEDNESDAY NIGHT. EXPECT A LULL
IN RAINFALL ACTIVITY THURSDAY. UPPER LEVEL FLOW FLATTENS ON FRIDAY.
MODELS DEVELOP A DEEP UPPER LEVEL RIDGE THAT SHOULD BRING SUBSIDENCE
AND RELATED WIDESPREAD DRIER CONDITIONS TO THE AREA SATURDAY NIGHT
THROUGH THE BEGINNING OF NEXT WEEK.
WENT WITH WPC FOR TEMPERATURES THROUGH THE PERIOD.
&&
.AVIATION /00Z MONDAY THROUGH FRIDAY/...
ISOLD TO SCT SHRA AND A FEW TSRA ACROSS THE AREA THIS EVE. THESE
SHOULD INCREASE IN COVERAGE LATER TONIGHT AS A SFC LOW TRACKS INTO
THE AREA FROM OH. MOST OF THE ACTIVITY SHOULD BE OVER N TERMINALS
WITH SOME MVFR CONDITIONS EXPECTED. OTHERWISE...EXPECT LOW CIGS TO
DEVELOP OVER THE AREA BY 09Z...WITH IFR AND PERHAPS LIFT/VLIFR
STRATUS FOR MOST TERMINALS...WITH SOME IFR VSBY POSSIBLE AS WELL.
STRATUS WILL LIFT BY 13Z FOR A RETURN TO VFR CONDITIONS...WITH
PERHAPS A BRIEF PERIOD OF MVFR CIGS IN THE TRANSITION. WILL BE
WATCHING FOR A FEW ROUNDS OF SHRA/TSRA TO CROSS THE AREA IN THE
AFTN AND ESPECIALLY THE EVE HRS. SOME OF THESE WILL BE STRONG TO
SVR BUT AT THIS DISTANCE...HAVE KEPT SOME VCTS IN.
FORECAST CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 00Z TUESDAY...
FORECAST CONFIDENCE:MEDIUM.
ALTERNATE SCENARIOS: EXTENT OF LOW STRATUS AND FG IN QUESTION.
AFTER 18Z MONDAY...IFR CONDITIONS POSSIBLE IN THUNDERSTORMS EACH
DAY.
.RLX WATCHES/WARNINGS/ADVISORIES...
WV...NONE.
OH...NONE.
KY...NONE.
VA...NONE.
&&
$$
SYNOPSIS...KMC/ARJ
NEAR TERM...KMC/30
SHORT TERM...ARJ
LONG TERM...JB/ARJ
AVIATION...30
AREA FORECAST DISCUSSION
NWS CHARLESTON WV
133 AM EDT SAT JUL 11 2015
.SYNOPSIS...
UNSETTLED AND WET PATTERN LINGERS INTO THE WEEKEND. A SERIES OF
UPPER LEVEL DISTURBANCES WILL CROSS THE AREA UNDER NORTHWEST FLOW
NEXT WEEK...KEEPING UNSETTLED CONDITIONS EACH DAY.
&&
.NEAR TERM /THROUGH TODAY/...
1030 PM UPDATE...
SEEING THE MCS/MCV TYPE SYS COMING TO FRUITION OVER SE OH AND NE
KY OVER THE LAST HR. LAST FEW IR SATELLITE IMAGES BEAR THIS OUT
ALONG WITH RADAR. 00Z NAM AND LAST FEW RUNS OF THE HRRR HAVE
LATCHED ON TO THIS NOW THAT IT HAS DEVELOPED. AS SUCH...HAVE
LEANED HEAVILY ON THESE MODELS FOR REMAINDER OF THE OVERNIGHT.
THERE IS GROWING CONCERN OF A RENEWED FLASH FLOOD EVENT IN THE C
LOWLANDS OVERNIGHT...OVER AREAS THAT HAVE BEEN HIT HARD THE PAST
FEW DAYS. QPF AMOUNTS OF 1 TO 2 INCHES UNDER A SOMEWHAT NARROW
BAND CAN BE EXPECTED ACROSS THE ROUTE 33 CORRIDOR AND INTO THE N
MTNS.
PREVIOUS DISCUSSION BELOW...
UNSETTLED WEATHER CONTINUES...LIKE A BROKEN RECORD THAT WONT FALL
OFF THE TURNTABLE.
FRONTAL BOUNDARY ACROSS SOUTHERN HALF OF THE CWA AT 1730Z. HIGH
PWS REMAIN ACROSS THE AREA...GENERALLY 1.6 TO 2 INCHES...ONCE
AGAIN. UPPER SHORTWAVE PUSHING EAST OUT OF THE MIDWEST...IS
HELPING TO GENERATE MORE SHOWERS AND THUNDERSTORMS. SOME WITH
FLOODING RAINS. FRONTAL BOUNDARY WILL LIFT SLIGHTLY NORTH TODAY AS
SHORTWAVE APPROACHES.
SOME FLASH FLOODING HAS ALREADY BEEN REPORTED WITH STORMS THAT
HAVE DEVELOPED...AND HAVE FLASH FLOOD WATCHES POSTED THROUGH
SATURDAY MORNING. THESE MAY BE A LITTLE LONG IN DURATION...BUT
WANTED TO ACCOUNT FOR THE DIFFERENCE IN MODEL TRENDS AND TIMING
OVERNIGHT...AND WILL LIKELY BE DROPPED SOMETIME LATE TONIGHT.
IN ADDITION...MCS ASSOCIATED WITH APPROACHING SHORTWAVE WILL
AFFECT AT LEAST WESTERN ZONES THIS AFTERNOON. STILL SOME
UNCERTAINTY AS TO HOW FAR EAST THE SEVERE THREAT WILL BE. HAVE A
WATCH OUT FOR WESTERN/SOUTHERN ZONES UNTIL 4 PM.
&&
.SHORT TERM /TONIGHT THROUGH MONDAY NIGHT/...
AN UPPER LEVEL RIDGE WILL BRING DRIER CONDITIONS TO THE AREA
SATURDAY NIGHT INTO EARLY SUNDAY. THEN...MODELS BRING A SHORT WAVE
AT H500 CROSSING THE AREA SUNDAY AFTERNOON THROUGH SUNDAY NIGHT.
WITH SFC DEWPOINTS IN THE MID TO UPPER 60S...PWATS INCREASING TO
AROUND 2 INCHES MODELS BRING A CONSIDERABLE AMOUNT OF QPF OVER THE
AREA LATE SUNDAY INTO EARLY MONDAY. THEREFORE...INCREASE POPS TO TO
HIGH CHANCE SUNDAY AND TO LIKELY SUNDAY NIGHT AND MONDAY.
UNDER NORTHWEST FLOW ALOFT...ADDITIONAL UPPER LEVEL DISTURBANCES
WILL KEEP UNSETTLED WEATHER THROUGH MONDAY NIGHT. ALTHOUGH THERE
WILL BE A SLIGHT DECREASE IN MOISTURE WITH PWATS GOING BACK TO
AROUND 1.5 INCHES MONDAY NIGHT.
WITH THE WET SOIL CONDITIONS...LUSH VEGETATION...CLOUDS AND
SHOWERS... TEMPERATURES WILL BE SEASONABLE BUT ALSO HUMID. THE
POTENTIAL FOR FLOODING CONTINUES TO BE A CONCERN FOR THIS PERIOD.
&&
.LONG TERM /TUESDAY THROUGH FRIDAY/...
A SERIES OF UPPER LEVEL DISTURBANCES UNDER NORTHWEST FLOW ALOFT WILL
CROSS THE AREA KEEPING THE PATTERN UNSETTLED THROUGH THE REMINDER OF
THE WEEK WITH CHANCES FOR SHOWERS AND THUNDERSTORMS EACH DAY.
ALLOWED CHANCE POPS ACROSS THE AREA DUE TO UNCERTAINTIES BY THE
MODELS IN THE LONG PERIOD. THEREFORE...ALLOWED SLIGHT CHANCE POPS
WEDNESDAY NIGHT ON.
WITH THE GROUNDS ALREADY SATURATED...WILL HAVE TO CONTINUE
MONITORING THE WEATHER CLOSELY EACH DAY DUE TO WATER CONCERNS.
WENT WITH WPC THINKING WITH TEMPERATURES...SKY...AND POPS THROUGH
THE PERIOD.
&&
.AVIATION /06Z SATURDAY THROUGH WEDNESDAY/...
GOING WITH THE LOW STRATUS ONCE THE SHOWERS PASS TO THE EAST OVER
THE REMAINDER OF THE OVERNIGHT PERIOD. THIS WILL BRING MVFR TO IFR
CONDITIONS...BUT SHOULD KEEP THE VISIBILITIES FROM GOING DOWN TOO
FAR THIS MORNING.
DRYING WILL TAKE PLACE AFTER 12Z TODAY...AND ONCE HEATING TAKES
PLACE...EXPECTING SLOW IMPROVEMENTS OF THE CEILINGS...BUT COULD
TAKE UNTIL 15-16Z TODAY TO REACH VFR.
VFR THROUGH THE REMAINDER OF THE TAF PERIOD...AS MID TO HIGH LEVEL
MOISTURE FROM THE NEXT SYSTEM COMING SHOULD KEEP FOG FROM BEING AN
ISSUE.
FORECAST CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 18Z
SATURDAY...
FORECAST CONFIDENCE: LOW TONIGHT.
ALTERNATE SCENARIOS: LOW STRATUS CLOUD FORMATION IS IN QUESTION.
AFTER 06Z SUNDAY...IFR POSSIBLE IN THUNDERSTORMS SUNDAY.
&&
WV...FLASH FLOOD WATCH THROUGH SATURDAY MORNING FOR WVZ005>008-
013>018-024>030-033>039-046-047.
OH...FLASH FLOOD WATCH UNTIL 8 AM EDT SATURDAY FOR OHZ087.
KY...FLASH FLOOD WATCH THROUGH SATURDAY MORNING FOR KYZ105.
FLASH FLOOD WATCH UNTIL 8 AM EDT SATURDAY FOR KYZ101>103.
VA...FLASH FLOOD WATCH THROUGH SATURDAY MORNING FOR VAZ003-004.
&&
.RLX WATCHES/WARNINGS/ADVISORIES...
WV...FLASH FLOOD WATCH UNTIL 11 AM EDT THIS MORNING FOR WVZ005>008-
013>018-024>030-033>039-046-047.
OH...FLASH FLOOD WATCH UNTIL 8 AM EDT THIS MORNING FOR OHZ087.
KY...FLASH FLOOD WATCH UNTIL 11 AM EDT THIS MORNING FOR KYZ105.
FLASH FLOOD WATCH UNTIL 8 AM EDT THIS MORNING FOR KYZ101>103.
VA...FLASH FLOOD WATCH UNTIL 11 AM EDT THIS MORNING FOR VAZ003-004.
&&
$$
SYNOPSIS...ARJ/SL
NEAR TERM...SL/30
SHORT TERM...ARJ
LONG TERM...JB/ARJ
AVIATION...30
AREA FORECAST DISCUSSION
NWS MEDFORD OR
222 PM PDT SAT JUL 11 2015
.DISCUSSION...TEMPERATURES ARE SIMILAR TO WHAT THEY WERE 24 HOURS
AGO...WHICH ARE BELOW NORMAL FOR THIS TIME OF YEAR. A WELL-DEFINED
TROUGH IS MOVING INTO THE COAST NOW...AND WILL BRING WITH IT THE
CHANCE FOR SHOWERS AT THE COAST THROUGH THE EVENING...AND SHOULD
PROVIDE ENOUGH ENERGY FOR SOME THUNDERSTORMS MAINLY EAST OF THE
CASCADES THIS AFTERNOON. MAINLY GENERIC SHOWERS ARE OCCURRING NOW
ALONG AND EAST OF THE CASCADES AND DON`T EXPECT MANY STORMS TODAY
BECAUSE INSTABILITY IS MARGINAL FOR STORMS IN THE FIRST PLACE. THE
LATEST HRRR OUTPUT REMAIN CONSISTENT WITH THIS IDEA.
TONIGHT...THE INCOMING TROUGH WILL KEEP THE CHANCE FOR SHOWERS IN
THE FORECAST AREA. TOMORROW IS TRENDING LESS UNSTABLE PER RECENT
MODEL RUNS...THOUGH STILL A BIT MORE UNSTABLE THAN TODAY. WE HAVE
KEPT CONFIDENCE WORDING IN THE FORECAST VERSUS COVERAGE...SIMPLY
BECAUSE THE PATTERN AND THE PARAMETERS THAT SUPPORT THUNDERSTORMS
ARE NOT VERY ROBUST TOMORROW AND THE HIGH RES NMM AND ARW MODELS
ALIGN WITH THIS THINKING. SAID MORE SUCCINCTLY...CONFIDENCE IS
NOT HIGH WE`LL HAVE MUCH THUNDERSTORM ACTIVITY TOMORROW.
TEMPERATURES TOMORROW WILL AGAIN BE 5 TO 10 DEGREES BELOW NORMAL.
ON MONDAY MIDLEVEL FLOW SWITCHES MORE WESTERLY AND THIS BRINGS IN
DRIER AIR ALOFT...FURTHER REDUCING THE CHANCE FOR SHOWERS AND
THUNDERSTORMS. TEMPERATURES MONDAY AND TUESDAY WILL REMAIN BELOW
NORMAL UNDER PERSISTENT UPPER TROUGHING.
WEDNESDAY INTO SATURDAY TEMPERATURES WILL GRADUALLY REBOUND AS
THE UPPER TROUGH AXIS NUDGES EASTWARD SOME...WARMING TEMPERATURES
A FEW DEGREES EACH DAY. MOSTLY DRY CONDITIONS ARE EXPECTED DURING
THIS TIMEFRAME. FRIDAY AND SATURDAY BOTH THE EC AND GFS...WITH
GOOD AGREEMENT AMONGST THE GFS ENSEMBLE MEMBERS...SHOW A HEFTY
UPPER RIDGE BUILDING OVER THE NE PAC WATERS. THE EC PEGS IT AT 561
DM. THIS PLACES OUR FORECAST AREA TO THE EAST OF THE RIDGE IN A
REGION OF NORTHERLY OR WESTERLY WINDS ALOFT...LIKELY KEEPING US
DRY AND PREVENTING ANY HEATWAVES. THE EVOLUTION OF THIS RIDGE WILL
LIKELY DICTATE OUR WEATHER OUT PAST DAY 7. OF NOTE ARE SOME
TROPICAL CYCLONES IN THE WEST PACIFIC THAT WILL ALSO LIKELY PLAY A
ROLE IN OUR EVOLVING WEATHER PATTERN IN THE EXTENDED...AND MAY
WREAK HAVOC ON MODEL CONSISTENCY IN THE NEXT FEW DAYS.
&&
.AVIATION...FOR THE 11/18Z TAF CYCLE...ALONG THE COAST AND IN THE
UMPQUA BASIN...MVFR CIGS HAVE CLEARED TO VFR. THE LOWER CONDITIONS
WILL MOVE BACK ONSHORE THIS EVENING. OVER THE REMAINDER OF THE
AREA...VFR CONDITIONS WILL PREVAIL...BUT THERE WILL BE ISOLATED TO
SCATTERED AFTERNOON AND EVENING THUNDERSTORMS WITH LOCAL OBSCURATION
OF HIGHER TERRAIN. WEST WINDS WILL BE A FEW MPH STRONGER DUE TO
INCREASING ONSHORE PRESSURE GRADIENT. /FB
&&
.MARINE...UPDATED 200 PM PDT SATURDAY 11 JULY 2015...LIGHT SOUTH
WINDS WILL PERSIST THROUGH TONIGHT AS A WEAK FRONT PASSES OVER THE
WATERS THIS EVENING. THERE WILL BE SOME LIGHT RAIN WITH THIS FRONTAL
PASSAGE BUT WINDS WILL REMAIN LIGHT. WINDS WILL GRADUALLY TURN
NORTHERLY SUNDAY INTO MONDAY. A THERMAL TROUGH WILL DEVELOP AND
STRENGTHEN MONDAY NIGHT INTO TUESDAY. THIS WILL INCREASE WINDS AND
SEAS WILL BECOME CHOPPY AND WIND-DRIVEN. WINDS MAY INCREASE TO GALE
FORCE BY WEDNESDAY AFTERNOON OFFSHORE AND SOUTH OF CAPE BLANCO.
SMALL CRAFT ADVISORY WINDS AND SEAS WILL DEVELOP OVER THE SOUTHERN
OUTER WATERS TUESDAY...SPREADING TO THE REST OF THE AREA BY
WEDNESDAY. -MND
&&
.FIRE WEATHER...UPDATED 300 PM PDT SATURDAY 11 JULY 2015...WITH
WESTERLY FLOW MOVING INTO THE FORECAST AREA BEHIND THE TROUGH..THE
MOIST AIR MASS WILL BE DISPLACED BY COOLER BUT MUCH DRIER AIR.
AFTERNOON HUMIDITY WILL BE ABOUT 15-20 PERCENT LOWER THAN
YESTERDAY. THE EXCEPTION IS ALONG THE COAST AND THE VALLEYS AND
LOWER SLOPES OF THE UMPQUA BASIN WHERE LOW LEVEL MARINE AIR IS
ENTRENCHED.
A TROUGH MOVING ACROSS SOUTHERN OREGON SUNDAY WILL PROVIDE TRIGGERS
FOR THUNDERSTORMS FROM THE CASCADES EASTWARD. THE MOST UNSTABLE AREA
WILL BE IN THE CASCADES FROM CRATER LAKE NORTH WHERE FORECAST
SOUNDING INDICATES LIFTED INDEX OF -3 IS POSSIBLE. OUTSIDE THIS AREA
IN KLAMATH AND LAKE COUNTIES..THERE APPEARS TO BE A MID LEVEL
CAPPING AND LIFTING OF THE PARCEL FROM THE CLOUD BASE ONLY GIVES
MARGINAL INSTABILITY.
BY WEDNESDAY NIGHT AND EARLY THURSDAY..A THERMAL TROUGH WILL EXPAND
NORTH INTO THE COASTAL ZONES SOUTHERN OREGON LASTING THROUGH
SATURDAY. EXPECT LOWERING NIGHT TIME HUMIDITY RECOVERY IN THE SECOND
HALF OF NEXT WEEK. /FB
&&
.MFR WATCHES/WARNINGS/ADVISORIES...
OR...NONE.
CA...NONE.
PACIFIC COASTAL WATERS...NONE.
$$
NSK/NSK/FJB
AREA FORECAST DISCUSSION
NWS GREENVILLE-SPARTANBURG SC
727 PM EDT SUN JUL 12 2015
.SYNOPSIS...
THE EAST COAST WILL REMAIN UNDER THE INFLUENCE OF AN UPPER
TROUGH...WITH MULTIPLE IMPULSES MOVING THROUGH THE AREA AND
INCREASING RAIN AND THUNDERSTORM CHANCES EACH DAY THROUGH THE FIRST
HALF OF THE WORK WEEK. A LOW PRESSURE SYSTEM AND STRONG FRONT WILL
PASS THROUGH THE REGION TUESDAY...WITH STRONG TO SEVERE STORMS
POSSIBLE. AFTER THE FRONT PASSES...AN UPPER HIGH WILL DRY OUT THE
FORECAST AREA FOR THE SECOND HALF OF THE WORK WEEK.
&&
.NEAR TERM /THROUGH MONDAY/...
AS OF 725 PM...NOT MUCH CHANGE TO THE FCST WITH THIS UPDATE. DID
TWEAK POPS TO LINE UP WITH LATEST RADAR TRENDS. THE LATEST LAPS AND
SPC MESOANALYSIS CAPE SHOWS SOME RECOVERY IN THE MTNS...BUT MOST OF
THE ISOLD CONVECTION HAS DEVELOPED NEAR I-85 FROM SPARTANBURG TO
SALISBURY NC. STILL MAY SEE SOME CONVECTION REACHING THE TN/NC
BORDER WITHIN THE NWLY STEERING FLOW. SO WILL LEAVE THE CHC POPS
THERE WITH THIS UPDATE. TEMPS/DEWPTS ARE ON TRACK.
AS OF 425 PM...HAVE BACKED OFF POP FURTHER FOR THE REST OF THIS AFTN
INTO THIS EVENING PER LATEST RADAR/SAT TRENDS. THE LATEST RAP AND
LAPS CAPE ANALYSES SHOW DECREASING INSTBY AND INCREASING CIN ACRS
THE ENTIRE CWFA THANKS TO THE THICK CIRRUS CLOUDS AND SFC DEWPTS
MAINLY IN THE LOWER 60S. CANNOT RULE OUT A FEW STRAY TSTMS...BUT THE
WINDOW SEEMS TO BE CLOSING. MEANWHILE...SCATTERED CONVECTION
UPSTREAM ACRS KY/TN MAY REACH THE TN BORDER COUNTIES OVER THE NEXT
FEW HOURS. SO WILL KEEP A HIGHER POP THERE. ANYTHING REACHING THE
MTNS WILL LIKELY BE ON A DISSIPATING TREND GIVEN THE LACK OF INSTBY.
AT 245 PM...RECENT RADAR TRENDS INDICATED DISSIPATING CONVECTION
ACROSS THE NC MTNS...ASSOCIATED WITH AN OLD MCS. A THICK SHIELD OF
DEBRIS CIRRUS HAS SPREAD ACROSS THE FA...WITH ONLY FAIR WEATHER CU
EAST OF THE MTNS. THICK CLOUD COVER HAS LIMITED AFTERNOON HEATING
ACROSS THE REGION. STEADY TEMPS COUPLED WITH SLOW DEWPOINT RECOVER
HAS LEFT THE I-77 CORRIDOR STABLE. AREAS ACROSS THE UPPER SAVANNAH
RIVER VALLEY MAY RANGE AROUND 2000 J/KG OF CAPE...POSSIBLY
SUPPORTING DEEPER CONVECTION. THE TIME HAS COME TO DEPART FROM A CAM
AND NAM SCENARIO OF NEW CONVECTION DEVELOPING ALONG THE OLD MCS COLD
POOL...I WILL LOWER POPS FOR THIS AFTERNOON AND EVENING.
OVERNIGHT...UNSETTLED NW MID LEVEL FLOW WILL CONTINUE ACROSS THE
REGION. GENERALLY...CONDITIONS ACROSS THE CWA WILL REMAIN DRY...WITH
A FEW STRAY SHRA/TSRA POSSIBLE NEAR THE TN BORDER. LOW TEMPS ARE
FORECAST TO RANGE FROM THE MID 60S WITHIN THE MTN VALLEYS TO LOW 70S
EAST.
ON MONDAY...EXPECTING THE HIGH DEBRIS CLOUDS TO DISSIPATE BY
SUNRISE...WITH MOSTLY TO PARTLY SUN SKY. TEMPERATURES SHOULD RISE
STEADILY AS THE REGION REMAINS UNDER AN AREA OF H85 WAA. IN
ADDITION...SW WINDS ARE FORECAST TO DEVELOP AND STRENGTHEN THROUGH
THE DAY...YIELDING SEVERAL DEGREES OF DEWPOINT RECOVERY. THE
COMBINATION OF FALLING H5 HEIGHTS...TEMPS PEAKING 3 TO 4 DEGREES
ABOVE NORMAL...AND DEWPOINTS INCREASE 3 TO 5 DEGREES FROM
SUNDAY...WILL RESULT IN MODERATE CAPE DURING THE AFTERNOON. IN
ADDITION...WIND FIELDS APPEAR TO STRENGTHEN WITHIN THE MID
LEVELS...RESULTING IN BRISK STEERING FLOW TO THE SE. I EXPECT THAT
TSRA WILL DEVELOP OVER THE RIDGES BY EARLY AFTERNOON...CARRIED OVER
THE FOOTHILLS AND PIEDMONT DURING THE MID TO LATE AFTERNOON. BASED
ON DEEP INSTABILITY AND ADEQUATE SHEAR...A FEW SVR TSRAS WILL BE
POSSIBLE.
&&
.SHORT TERM /MONDAY NIGHT THROUGH WEDNESDAY/...
AS OF 245 PM SUNDAY...A NORTHWESTERLY ALOFT IS EXPECTED TO PREVAIL
ACROSS OUR FORECAST AREA (FA) FOR THIS PART OF THE FORECAST CYCLE...
WHILE A SERIES OF SHORT WAVES (S/W`S) RIPPLE SOUTHEASTWARD. THE SUITE
OF MODELS...ALTHOUGH DIFFERING IN TIMING/EXACT LOCATIONS OF SAID
S/W`S...HAVE A SIMILAR THEME OF BRING A PACKET OF ENERGY ACROSS OUR
FA MONDAY NIGHT. THE ENERGY ALOFT...WITH DPVA...SHOULD INTERCEPT
INCREASING MOISTURE VALUES AND ALLOW CLUSTERS OF STORMS TO DEVELOP OR
MOVE OFF THE MOUNTAINS FROM EARLIER IN THE DAY. THE STORMS MAY
CONTINUE WELL INTO THE EVENING...DRIVEN BY LOCAL COLD POOL
INTERACTIONS WITH A MICROBURST/WIND DAMAGE POTENTIAL. WE WILL HAVE
OUR HIGHEST POPS IN THE NC/FAR NE TN MOUNTAINS...WHERE BOTH THE NAM
AND GFS WERE SHOWING EXTREME SURFACE BASED INSTABILITY. IT APPEARS
THIS ACTIVITY WILL BE SEPARATED FROM THE ACTION EXPECTED WELL OFF TO
THE NORTHWEST. UPSHOT WE WILL HAVE A NON-DIURNAL POP DISTRIBUTION...
WITH POPS INCREASING UNTIL MIDNIGHT...THEN BACKING DOWN. THE SLIGHT
RISK MONDAY LOOKS WELL PLACED BASED ON VARIOUS INSTABILITY
PARAMETERS.
WE DO NOT PLAN TO FOLLOW THE IDEA OF THE GFS WITH WHAT APPEARS TO BE
A CONVECTIVE SCHEME BLOW-UP ALLOWING DAYBREAK CONVECTION TO HIT OUR
NORTHERN FA.
TRYING TO SENSIBLY PUT TOGETHER OUR CONVECTIVE TRENDS FROM TUESDAY
INTO WEDNESDAY WILL BE HIGHLY DEPENDENT ON S/W TIMING AND COLD POOL
INTERACTIONS. WE ARE GOING TO TRY AND FOLLOW THE PRIMARY S/W AND
UPPER TROUGH AXIS SOUTHEASTWARD INTO OUR FA TUESDAY AFTERNOON AND
THROUGH THE EVENING. AGAIN EXTREME INSTABILITY IN THE WEST IS THE
MOST LIKELY AREA TO START...ALTHOUGH ACTIVITY FROM THE NORTH...MAY
SEND AN OUTFLOW AND KICK OFF THE PROCESS. ONCE AGAIN WE ARE
HIGHLIGHTING AN UPTICK IN POPS TUESDAY AFTERNOON AND TUESDAY
NIGHT...AS TIMING DIFFERENCES FILTER IN. NEVERTHELESS INSTABILITY
PARAMETERS WILL BE SUCH THAT PERHAPS ALL MODES OF SEVERE WEATHER
WILL BE POSSIBLE.
A DIFFERENCE IN THE SURFACE FRONTAL PATTERN TREND LEADS TO KEEPING
CHANCE POPS GOING WEDNESDAY...ALTHOUGH WE HAVE FAVORED THE UPSTATE
SOUTH CAROLINA PIEDMONT AND ADJACENT AREAS OF NE TN.
WE HAVE FOLLOWED GUIDE TEMPERATURES FAIRLY CLOSELY THIS SECTION...
WHICH MAINTAINS CONTINUITY FROM THE PREVIOUS FORECAST.
&&
.LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/...
AS OF 230 PM SUNDAY...THE MEDIUM RANGE BEGINS 00Z THURSDAY JUST
AFTER THE PASSAGE OF THE 500MB TROUGH AXIS AND ASSOCIATED FRONTAL
BOUNDARY. THOUGH THE FRONTAL PASSAGE DOES NOT APPEAR TO BE
COMPLETELY CLEAN...HEIGHTS BEGIN TO RISE ONCE AGAIN AT THE END OF
NEXT WEEK. MODEST DRYING OCCURS NEXT WEEKEND AS THE UPPER LEVEL
RIDGE BUILDS BACK INTO THE SOUTHEAST...SO POPS WERE KEPT NEAR TO
BELOW CLIMO AND FOLLOW A DIURNAL TREND. FROM THIS POINT ON MODELS
DIVERGE ON THE STRENGTH AND TIMING OF FEATURES...SO THE FORECAST IS
WEIGHTED MORE TOWARDS AN ECMWF SOLUTION DUE TO BETTER RUN-TO-RUN
CONSISTENCY. THE UPPER LEVEL ANTICYCLONE RETROGRESSES BACK TOWARDS
THE SOUTHWEST ONCE AGAIN BY THE BEGINNING OF NEXT WEEK...AND AN
UPPER TROUGH DIGS INTO THE SOUTHEAST. AN ACCOMPANYING COLD FRONT
WILL APPROACH THE SOUTHERN APPALACHIANS AND MOISTEN THE
AIRMASS...LIKELY DRIVING UP POPS ONCE AGAIN TO BEGIN THE WORK WEEK.
THE EXTENDED PERIOD BEGINS WITH MAX TEMPS ABOUT A CATEGORY ABOVE
CLIMO...AND INCREASING HEIGHTS THROUGH NEXT WEEKEND WILL ALLOW HIGHS
TO WARM EVEN MORE TO ALMOST 10 DEGREES ABOVE AVERAGE.
&&
.AVIATION /00Z MONDAY THROUGH FRIDAY/...
AT KCLT AND ELSEWHERE...THERE HAS BEEN ENOUGH LINGERING INSTBY FOR A
FEW STRAY SHRA AND TSRA ACRS THE AREA. HOWEVER...THAT ACTIVITY SHUD
DISSIPATE THIS EVENING WITH LOSS OF DAYTIME HEATING. UPSTREAM
CONVECTION CONTINUES TO DEVELOP ACRS KY/TN...AND WILL PROVIDE PLENTY
OF DEBRIS CIRRUS THRU MOST OF THE NIGHT. GIVEN LACK OF RAINFALL AT
ANY OF THE TAF SITES...I DO NOT EXPECT MUCH FOG POTENTIAL. WINDS
WILL BE LIGHT AND SOMEWHAT VARIABLE TONIGHT THRU MONDAY
MORNING...BUT GENERALLY FAVOR SW ACRS THE UPSTATE AND N OR NW AT THE
NC SITES...THANKS TO A WEAK BOUNDARY BISECTING THE AREA FROM NW TO
SE. ON MONDAY...GUIDANCE SHOWS MORE TYPICAL MID SUMMER INSTBY IN THE
SOUNDINGS...WHICH SHUD RESULT IN AT LEAST SCATTERED SHRA AND TSRA
DURING THE AFTN HOURS. WILL GO WITH PROB30 AT ALL SITES.
OUTLOOK...THE WEATHER PATTERN WILL BE MORE FAVORABLE FOR MAINLY
AFTERNOON/EVENING SHOWERS AND THUNDERSTORMS THRU MIDWEEK.
HOWEVER...THERE COULD BE SOME ORGANIZED THUNDERSTORMS THAT MOVE
ACROSS THE REGION LATE TUESDAY NIGHT. LOW CLOUDS AND FOG COULD ALSO
DEVELOP IN THE MORNING AT PLACES THAT HAVE SHOWER ACTIVITY THE DAY
BEFORE...AND IN MTN AND RIVER VALLEYS.
CONFIDENCE TABLE...
23-05Z 05-11Z 11-17Z 17-18Z
KCLT HIGH 100% HIGH 100% HIGH 95% HIGH 100%
KGSP HIGH 100% HIGH 100% HIGH 100% HIGH 100%
KAVL HIGH 100% HIGH 100% MED 60% HIGH 100%
KHKY HIGH 100% HIGH 100% HIGH 100% HIGH 100%
KGMU HIGH 100% HIGH 100% HIGH 100% HIGH 100%
KAND HIGH 100% HIGH 100% HIGH 83% 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...LEV
NEAR TERM...ARK/NED
SHORT TERM...TS
LONG TERM...LEV
AVIATION...ARK
AREA FORECAST DISCUSSION
NWS ABERDEEN SD
324 PM CDT SAT JUL 11 2015
.SHORT TERM...(THIS EVENING THROUGH MONDAY NIGHT)
ISSUED AT 324 PM CDT SAT JUL 11 2015
LOW CONFIDENCE ON CONVECTION FOR THE AFTERNOON/EVENING. 700MB
READINGS ARE IN THE +8 TO +11C RANGE...WITH WARMEST READINGS OVERTOP
THE DRY LINE BETWEEN KPIR/KMBG. TEMPERATURES ARE IN THE UPPER
80S...AND DEWPOINTS ARE APPROACHING 70F...ENOUGH TO GENERATE OVER
4000 J/KG MLCAPE. WINDS THROUGH THE PROFILES ARE RELATIVELY WEAK
WITH SOME DIRECTIONAL SHEAR. THESE INGREDIENTS ARE ENOUGH TO WARRANT
AN SPC SLIGHT RISK OUTLOOK FOR MUCH OF THE CWA. POOR OVERALL
CONFIDENCE STEMS FORM THE LACK OF ANY UPPER WAVE...AND A LACK OF
CONVECTION BEING GENERATED IN HIGH RES GUIDANCE WITH ONLY THE MOST
RECENT ITERATIONS OF THE HRRR DEPICTING ANY STORMS. BEST
ENVIRONMENT MAY BE AHEAD OF THE MID LEVEL WARM ADVECTION IN FAR
NORTHEAST COUNTIES...BUT ALSO ALONG THE SURFACE TROF IF WE CAN BREAK
THE CAP...WITH BISMARCK 18Z SOUNDING INDICATING A CONVECTIVE
TEMPERATURE IN THE LOW 90S.
A MORE DISCERNIBLE WAVE IS EVIDENT FOR SUNDAY. THE DRY LINE WILL
ALSO BE PUSHED INTO THE JAMES VALLEY...SO TEMPERATURES COULD MAX OUT
IN THE UPPER 90S WITH A FEW SPOTS AROUND 100. WILL LEAVE HEAT
ADVISORY HEADLINE IN PLACE.
NORTHWEST FLOW FOLLOWS FOR MONDAY...WITH HIGH PRESSURE TO THE WEST.
THE RESULT WILL BE A DECENT FETCH OUT OF THE CANADIAN WILDFIRE
REGION AND MORE SMOKE IN THE AREA. TEMPERATURES WILL BE A TAD COOLER
BUT STILL A FEW DEGREES ABOVE AVERAGE THANKS TO WEAK COLD ADVECTION.
CANT RULE OUT AN ISOLATED HEAT OF THE AFTERNOON STORM MONDAY THANKS
TO STEEP LOW/MID LEVEL LAPSE RATES.
.LONG TERM...(TUESDAY THROUGH SATURDAY)
ISSUED AT 324 PM CDT SAT JUL 11 2015
THE LATEST LONG TERM MODELS CONTINUE TO INDICATE A FAIRLY ACTIVE
PATTERN ACROSS THE REGION THROUGH THE PERIOD. MID LEVEL RIDGING
EARLY IN THE PERIOD WILL GIVE WAY TO FALLING HEIGHTS AND PLENTY OF
S/W ENERGY AS A DECENT JET DIGS A TROF INTO THE NORTHWEST CONUS.
THE TROF IS EXPECTED TO TRACK ACROSS THE NORTHERN PLAINS LATE THIS
COMING WEEK AND NEXT WEEKEND WITH PRETTY DECENT CHANCES FOR
SHOWERS/STORMS. LATE IN THE PERIOD SHOULD FEATURE SOME DRYNESS AS
SFC HIGH BUILDS INTO THE AREA. TEMPERATURES SHOULD AVERAGE OUT NEAR
NORMAL.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON)
ISSUED AT 1222 PM CDT SAT JUL 11 2015
OTHER THAN SOME MVFR CLOUDS EARLY THIS AFTERNOON AND LATE
TNT...THE REST OF THE TAF PERIOD SHOULD MOSTLY VFR. LATE
AFTN/EVENING THUNDERSTORMS ARE POSSIBLE AT KABR/KATY BUT FOR NOW
CONFIDENCE AND EXPECTED COVERAGE IS LOW ENOUGH TO LEAVE OUT OF
THE FORECAST.
&&
.ABR WATCHES/WARNINGS/ADVISORIES...
SD...HEAT ADVISORY FROM 1 PM TO 7 PM CDT SUNDAY FOR SDZ006>008-011-
018>023.
MN...HEAT ADVISORY FROM 1 PM TO 7 PM CDT SUNDAY FOR MNZ039-046.
&&
$$
SHORT TERM...CONNELLY
LONG TERM...TDK
AVIATION...TDK
AREA FORECAST DISCUSSION
NWS SIOUX FALLS SD
1218 PM CDT SAT JUL 11 2015
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 355 AM CDT SAT JUL 11 2015
MODELS CONTINUE TO BRING WEAK THERMAL SUPPORT FOR SHOWER AND
THUNDERSTORM DEVELOPMENT EAST ACROSS THE AREA THIS MORNING. SHORT
TERM MODELS SUCH AS THE HRRR AND HOP/WRF KEEP THE CONVECTION VERY
SPOTTY AND THIS LOOKS REASONABLE. WILL KEEP POPS AT CHANCE FOR NOW
AND ENHANCE AS DEVELOPMENT WARRANTS.
THIS ACTIVITY SHOULD DECREASE TO THE EAST NORTHEAST THIS AFTERNOON
AS CAPPING FROM INCREASINGLY WARM AIR SPREADS INTO THE AREA. BY LATE
IN THE DAY THIS ACTIVITY...IF THERE IS ANY LEFT...SHOULD BE CONFINED
TO THE FAR EASTERN PART OF THE AREA WITH SOME MINIMAL NEW
DEVELOPMENT POSSIBLE. MEANWHILE...STRONG WARMING OVER THE WESTERN
PART OF THE AREA MAY INCLUDE ENOUGH HEATING TO BREAK THE CAP FAR
WEST LATE THIS AFTERNOON AS THE DRYLINE GETS CLOSER. THIS IDEA WAS
DEEMED REASONABLE IN THE EARLIER FORECAST AND STILL LOOKS SO...BUT
AGAIN ACTIVITY SHOULD BE PRETTY SPARSE.
THE SURGE OF WARMING AND HEATING SHOULD TAKE TEMPERATURES UP TO THE
90S WEST...WITH INCREASINGLY HUMID 80S EAST. LOW CLOUDS WHICH WILL
BE PREVALENT IN AREAS EAST THIS MORNING SHOULD HEAT OUT AND
GENERALLY DECREASE LATE MORNING AND AFTERNOON.
FOR TONIGHT WILL KEEP SOME CHANCE OF STORMS FAR EAST WITH THE
STRONG INSTABILITY. OTHERWISE A WARM NIGHT IS IN STORE WITH LOW
TEMPERATURES WITHING A COUPLE DEGREES OF 70 EVERYWHERE.
.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 355 AM CDT SAT JUL 11 2015
HEAT AT THE FOREFRONT OF MID RANGE CONCERNS. CAPPED ENVIRONMENT WILL
BE IN PLACE WITH STRONG ELEVATED MIXED LAYER TRAPPING NEAR SURFACE
MOISTURE QUITE EFFECTIVELY ACROSS MUCH OF THE AREA THROUGH THE DAY.
LIKELIHOOD OF SOME CONVECTION TO OUR SOUTH AGAIN THIS EVENING WILL
ACT TO MODIFY ENVIRONMENT TO SOME DEGREE...AND SOUTH TO SOUTHEAST
FLOW NEAR THE SURFACE WILL REINFORCE PRESENCE OF BOUNDARY LAYER
MOISTURE INTO THE AFTERNOON FROM THE JAMES VALLEY EASTWARD.
EVENTUALLY...APPEARS AS IF THE SURFACE TROUGH WILL BE PUSHING INTO
THE JAMES VALLEY OR A BIT EAST BY LATE SUNDAY AFTERNOON...AND OTHER
THAN A BUFFER OF SLIGHTLY BETTER MIXING JUST TO THE EAST OF THIS...
MIXING WILL BE QUITE CHALLENGED BY THE STRONG INVERSION. AS A
RESULT...WILL PROBABLY NOT GET QUITE AS TOASTY FROM AROUND I29
EASTWARD...BUT STILL PLENTY WARM INTO THE LOWER 90S...WHILE AREAS
WEST OF THE TROUGH ARE LIKELY TO FIND A FEW SPOTS REACHING THE
CENTURY MARK...AS DEWPOINTS MIX GREATLY INTO THE 50S. EVEN WITH THE
SLIGHTLY LOWER TEMPERATURE EXPECTATIONS...DEWPOINTS WILL SOAR WELL
INTO THE 70S...AND WILL RESULT IN A LARGE AREA OF 100 TO 105 DEGREE
AFTERNOON HEAT INDEX. JAMES VALLEY LOCATIONS WILL HAVE THE WORST
EARLY AFTERNOON BEFORE START TO SEE MIXING LOWERING THE MOISTURE
CONTENT. WITH THE LONG PERIOD SINCE LAST EXTREME HEAT AND THE
NUMEROUS OUTDOOR ACTIVITIES ON THE WEEKEND...HAVE DECIDED TO ISSUE
HEAT ADVISORY FROM THE JAMES VALLEY EASTWARD THROUGH THE AFTERNOON
ON SUNDAY.
NOT TOTALLY IMPOSSIBLE TO FIND A ROGUE HIGH BASED THUNDERSTORM TO
START THE DAY...BUT SUCH A LOW CHANCE THAT HAVE KEPT CLEAR OF THE
FORECAST. OTHERWISE...WAVE WILL BEGIN TO PUSH ACROSS THE MEAN UPPER
RIDGE DURING SUNDAY AFTERNOON AND EVENING...AND START TO ERODE SOME
OF THE WARMEST AIR ALOFT. REALLY HARD TO PICTURE THERE BEING ENOUGH
LIFT TO BREAK RESIDUAL INVERSION EVEN AFTER FULL HEATING...WITH
CIN LIKELY IN THE 50-150 J/KG RANGE FOR MOST LOCATIONS. OUTSIDE
CHANCE THERE COULD BE A GOLDILOCKS LOCATION WHERE THE WEAKENING
CAP AND FORCING ARE JUST RIGHT...BUT AT THIS POINT NOT WORTH
CLUTTERING THE FORECAST WITH ISOLATED THREAT. HOWEVER...KEEP
AWARE...AS THERE IS MORE THAN ENOUGH POTENTIAL INSTABILITY TO MAKE
FOR A STRONGER STORM. PERHAPS A BIT BETTER CHANCE FOR THINGS TO
COME TOGETHER OVER THE NORTHEASTERN CWA CLOSEST TO THE UPPER
FORCING DURING THE EVENING...BUT SHOULD BE A PRETTY QUICKLY
CLOSING WINDOW AS STRONGER FORCING MOVES QUICKLY PAST AND DEEPER
DRYING ON WEST TO NORTHWEST FLOW SPREADS ACROSS THE AREA. NEAR
SURFACE WINDS WILL DECOUPLE AND ALLOW THE SURFACE TO RECOVER QUITE
A BIT IN THOSE FULLY MIXED AREAS...AND RETAIN SOME UPPER 60S
DEWPOINT VALUES IN THE SOUTHEAST.
ON MONDAY...AS SHOULD BE ANOTHER VERY WARM DAY...THE VERY HUMID
CONDITIONS WILL BE RELAXED SOMEWHAT OVER A GOOD PORTION OF THE
AREA...WITH HIGHEST READINGS EAST OF I 29 DURING THE MORNING HOURS.
DEEPER MIXING SHOULD TAKE DEWPOINTS INTO THE 50S WEST TO LOWER TO
MID 60S EAST DURING THE AFTERNOON...WITH WINDS AT 15 TO 25 MPH AT
TIMES. THE HEAT INDEX WILL AGAIN CLIMB INTO THE 90S. WILL HAVE TO
SEE IF WE GET ANOTHER INCREASE IN SMOKE BEHIND THE BOUNDARY AS IT
PUSHES SOUTHWARD SUNDAY NIGHT/MONDAY...AS COULD IMPACT TEMPS A
COUPLE DEGREES.
THE EXTENDED RANGE FROM TUESDAY THROUGH FRIDAY WOULD SEEMINGLY BE A
BIT MORE ACTIVE IN GENERAL...WITH RIDGE ACROSS THE NORTHERN
PLAINS...BREACHED PERIODICALLY WITH SYSTEMS COMING OUT OF THE WEST
TO SOUTHWEST FLOW ALOFT. A COMMON FEATURE IN MODELS IS WAVE AROUND
WEDNESDAY...AND HAVE MAINTAINED HIGHER PRECIP CHANCES WITH THIS
FEATURE. TEMPS SHOULD REMAIN FROM NORMAL TO SLIGHTLY ABOVE NORMAL...
BUT WILL HAVE TO WATCH TO SEE IF SLIGHTLY MORE AMPLIFIED SOLUTION IN
ECMWF COULD KEEP A BETTER BACKDOOR BOUNDARY AROUND MIDWEEK. ANOTHER
WAVE HAS PROXIMITY TO THE END OF THE FORECAST CYCLE...BUT
DRASTICALLY DIFFERING TIMING IN GREATER ENSEMBLE OF SOLUTIONS FOR
SURFACE REFLECTION. WATCHING FOR ANOTHER EASTWARD SURGE IN WARMER
AIR AHEAD OF THIS WAVE...WHICH COULD BE ON THE WAY FOR LATE WEEK.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON)
ISSUED AT 1216 PM CDT SAT JUL 11 2015
MVFR CEILINGS OVER PORTIONS OF THE AREA WILL CONTINUE TO BREAK UP
THROUGH MID AFTERNOON. OTHERWISE...VFR CONDITIONS ARE EXPECTED
THROUGH THE TAF PERIOD.
&&
.FSD WATCHES/WARNINGS/ADVISORIES...
SD...HEAT ADVISORY FROM 1 PM TO 7 PM CDT SUNDAY FOR SDZ038>040-
053>056-059>062-065>071.
MN...HEAT ADVISORY FROM 1 PM TO 7 PM CDT SUNDAY FOR MNZ071-072-080-
081-089-090-097-098.
IA...HEAT ADVISORY FROM 1 PM TO 7 PM CDT SUNDAY FOR IAZ001>003-
012>014-020>022-031-032.
NE...HEAT ADVISORY FROM 1 PM TO 7 PM CDT SUNDAY FOR NEZ013-014.
&&
$$
SHORT TERM...
LONG TERM...CHAPMAN
AVIATION...JM
AREA FORECAST DISCUSSION
NWS SIOUX FALLS SD
630 AM CDT SAT JUL 11 2015
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 355 AM CDT SAT JUL 11 2015
MODELS CONTINUE TO BRING WEAK THERMAL SUPPORT FOR SHOWER AND
THUNDERSTORM DEVELOPMENT EAST ACROSS THE AREA THIS MORNING. SHORT
TERM MODELS SUCH AS THE HRRR AND HOP/WRF KEEP THE CONVECTION VERY
SPOTTY AND THIS LOOKS REASONABLE. WILL KEEP POPS AT CHANCE FOR NOW
AND ENHANCE AS DEVELOPMENT WARRANTS.
THIS ACTIVITY SHOULD DECREASE TO THE EAST NORTHEAST THIS AFTERNOON
AS CAPPING FROM INCREASINGLY WARM AIR SPREADS INTO THE AREA. BY LATE
IN THE DAY THIS ACTIVITY...IF THERE IS ANY LEFT...SHOULD BE CONFINED
TO THE FAR EASTERN PART OF THE AREA WITH SOME MINIMAL NEW
DEVELOPMENT POSSIBLE. MEANWHILE...STRONG WARMING OVER THE WESTERN
PART OF THE AREA MAY INCLUDE ENOUGH HEATING TO BREAK THE CAP FAR
WEST LATE THIS AFTERNOON AS THE DRYLINE GETS CLOSER. THIS IDEA WAS
DEEMED REASONABLE IN THE EARLIER FORECAST AND STILL LOOKS SO...BUT
AGAIN ACTIVITY SHOULD BE PRETTY SPARSE.
THE SURGE OF WARMING AND HEATING SHOULD TAKE TEMPERATURES UP TO THE
90S WEST...WITH INCREASINGLY HUMID 80S EAST. LOW CLOUDS WHICH WILL
BE PREVALENT IN AREAS EAST THIS MORNING SHOULD HEAT OUT AND
GENERALLY DECREASE LATE MORNING AND AFTERNOON.
FOR TONIGHT WILL KEEP SOME CHANCE OF STORMS FAR EAST WITH THE
STRONG INSTABILITY. OTHERWISE A WARM NIGHT IS IN STORE WITH LOW
TEMPERATURES WITHING A COUPLE DEGREES OF 70 EVERYWHERE.
.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 355 AM CDT SAT JUL 11 2015
HEAT AT THE FOREFRONT OF MID RANGE CONCERNS. CAPPED ENVIRONMENT WILL
BE IN PLACE WITH STRONG ELEVATED MIXED LAYER TRAPPING NEAR SURFACE
MOISTURE QUITE EFFECTIVELY ACROSS MUCH OF THE AREA THROUGH THE DAY.
LIKELIHOOD OF SOME CONVECTION TO OUR SOUTH AGAIN THIS EVENING WILL
ACT TO MODIFY ENVIRONMENT TO SOME DEGREE...AND SOUTH TO SOUTHEAST
FLOW NEAR THE SURFACE WILL REINFORCE PRESENCE OF BOUNDARY LAYER
MOISTURE INTO THE AFTERNOON FROM THE JAMES VALLEY EASTWARD.
EVENTUALLY...APPEARS AS IF THE SURFACE TROUGH WILL BE PUSHING INTO
THE JAMES VALLEY OR A BIT EAST BY LATE SUNDAY AFTERNOON...AND OTHER
THAN A BUFFER OF SLIGHTLY BETTER MIXING JUST TO THE EAST OF THIS...
MIXING WILL BE QUITE CHALLENGED BY THE STRONG INVERSION. AS A
RESULT...WILL PROBABLY NOT GET QUITE AS TOASTY FROM AROUND I29
EASTWARD...BUT STILL PLENTY WARM INTO THE LOWER 90S...WHILE AREAS
WEST OF THE TROUGH ARE LIKELY TO FIND A FEW SPOTS REACHING THE
CENTURY MARK...AS DEWPOINTS MIX GREATLY INTO THE 50S. EVEN WITH THE
SLIGHTLY LOWER TEMPERATURE EXPECTATIONS...DEWPOINTS WILL SOAR WELL
INTO THE 70S...AND WILL RESULT IN A LARGE AREA OF 100 TO 105 DEGREE
AFTERNOON HEAT INDEX. JAMES VALLEY LOCATIONS WILL HAVE THE WORST
EARLY AFTERNOON BEFORE START TO SEE MIXING LOWERING THE MOISTURE
CONTENT. WITH THE LONG PERIOD SINCE LAST EXTREME HEAT AND THE
NUMEROUS OUTDOOR ACTIVITIES ON THE WEEKEND...HAVE DECIDED TO ISSUE
HEAT ADVISORY FROM THE JAMES VALLEY EASTWARD THROUGH THE AFTERNOON
ON SUNDAY.
NOT TOTALLY IMPOSSIBLE TO FIND A ROGUE HIGH BASED THUNDERSTORM TO
START THE DAY...BUT SUCH A LOW CHANCE THAT HAVE KEPT CLEAR OF THE
FORECAST. OTHERWISE...WAVE WILL BEGIN TO PUSH ACROSS THE MEAN UPPER
RIDGE DURING SUNDAY AFTERNOON AND EVENING...AND START TO ERODE SOME
OF THE WARMEST AIR ALOFT. REALLY HARD TO PICTURE THERE BEING ENOUGH
LIFT TO BREAK RESIDUAL INVERSION EVEN AFTER FULL HEATING...WITH
CIN LIKELY IN THE 50-150 J/KG RANGE FOR MOST LOCATIONS. OUTSIDE
CHANCE THERE COULD BE A GOLDILOCKS LOCATION WHERE THE WEAKENING
CAP AND FORCING ARE JUST RIGHT...BUT AT THIS POINT NOT WORTH
CLUTTERING THE FORECAST WITH ISOLATED THREAT. HOWEVER...KEEP
AWARE...AS THERE IS MORE THAN ENOUGH POTENTIAL INSTABILITY TO MAKE
FOR A STRONGER STORM. PERHAPS A BIT BETTER CHANCE FOR THINGS TO
COME TOGETHER OVER THE NORTHEASTERN CWA CLOSEST TO THE UPPER
FORCING DURING THE EVENING...BUT SHOULD BE A PRETTY QUICKLY
CLOSING WINDOW AS STRONGER FORCING MOVES QUICKLY PAST AND DEEPER
DRYING ON WEST TO NORTHWEST FLOW SPREADS ACROSS THE AREA. NEAR
SURFACE WINDS WILL DECOUPLE AND ALLOW THE SURFACE TO RECOVER QUITE
A BIT IN THOSE FULLY MIXED AREAS...AND RETAIN SOME UPPER 60S
DEWPOINT VALUES IN THE SOUTHEAST.
ON MONDAY...AS SHOULD BE ANOTHER VERY WARM DAY...THE VERY HUMID
CONDITIONS WILL BE RELAXED SOMEWHAT OVER A GOOD PORTION OF THE
AREA...WITH HIGHEST READINGS EAST OF I 29 DURING THE MORNING HOURS.
DEEPER MIXING SHOULD TAKE DEWPOINTS INTO THE 50S WEST TO LOWER TO
MID 60S EAST DURING THE AFTERNOON...WITH WINDS AT 15 TO 25 MPH AT
TIMES. THE HEAT INDEX WILL AGAIN CLIMB INTO THE 90S. WILL HAVE TO
SEE IF WE GET ANOTHER INCREASE IN SMOKE BEHIND THE BOUNDARY AS IT
PUSHES SOUTHWARD SUNDAY NIGHT/MONDAY...AS COULD IMPACT TEMPS A
COUPLE DEGREES.
THE EXTENDED RANGE FROM TUESDAY THROUGH FRIDAY WOULD SEEMINGLY BE A
BIT MORE ACTIVE IN GENERAL...WITH RIDGE ACROSS THE NORTHERN
PLAINS...BREACHED PERIODICALLY WITH SYSTEMS COMING OUT OF THE WEST
TO SOUTHWEST FLOW ALOFT. A COMMON FEATURE IN MODELS IS WAVE AROUND
WEDNESDAY...AND HAVE MAINTAINED HIGHER PRECIP CHANCES WITH THIS
FEATURE. TEMPS SHOULD REMAIN FROM NORMAL TO SLIGHTLY ABOVE NORMAL...
BUT WILL HAVE TO WATCH TO SEE IF SLIGHTLY MORE AMPLIFIED SOLUTION IN
ECMWF COULD KEEP A BETTER BACKDOOR BOUNDARY AROUND MIDWEEK. ANOTHER
WAVE HAS PROXIMITY TO THE END OF THE FORECAST CYCLE...BUT
DRASTICALLY DIFFERING TIMING IN GREATER ENSEMBLE OF SOLUTIONS FOR
SURFACE REFLECTION. WATCHING FOR ANOTHER EASTWARD SURGE IN WARMER
AIR AHEAD OF THIS WAVE...WHICH COULD BE ON THE WAY FOR LATE WEEK.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SUNDAY MORNING)
ISSUED AT 624 AM CDT SAT JUL 11 2015
UNTIL 11/16Z FREQUENT CEILINGS 1-3K FT AND VISIBILITIES 3-5SM/BR
WITH LOCAL CEILINGS BELOW 1K FEET. AFTER 12/16Z VFR. ISOLATED
SHRA/TSRA UNTIL 12/03Z.
&&
.FSD WATCHES/WARNINGS/ADVISORIES...
SD...HEAT ADVISORY FROM 1 PM TO 7 PM CDT SUNDAY FOR SDZ038>040-
053>056-059>062-065>071.
MN...HEAT ADVISORY FROM 1 PM TO 7 PM CDT SUNDAY FOR MNZ071-072-080-
081-089-090-097-098.
IA...HEAT ADVISORY FROM 1 PM TO 7 PM CDT SUNDAY FOR IAZ001>003-
012>014-020>022-031-032.
NE...HEAT ADVISORY FROM 1 PM TO 7 PM CDT SUNDAY FOR NEZ013-014.
&&
$$
SHORT TERM...
LONG TERM...CHAPMAN
AVIATION...
AREA FORECAST DISCUSSION
NWS SIOUX FALLS SD
356 AM CDT SAT JUL 11 2015
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 355 AM CDT SAT JUL 11 2015
MODELS CONTINUE TO BRING WEAK THERMAL SUPPORT FOR SHOWER AND
THUNDERSTORM DEVELOPMENT EAST ACROSS THE AREA THIS MORNING. SHORT
TERM MODELS SUCH AS THE HRRR AND HOP/WRF KEEP THE CONVECTION VERY
SPOTTY AND THIS LOOKS REASONABLE. WILL KEEP POPS AT CHANCE FOR NOW
AND ENHANCE AS DEVELOPMENT WARRANTS.
THIS ACTIVITY SHOULD DECREASE TO THE EAST NORTHEAST THIS AFTERNOON
AS CAPPING FROM INCREASINGLY WARM AIR SPREADS INTO THE AREA. BY LATE
IN THE DAY THIS ACTIVITY...IF THERE IS ANY LEFT...SHOULD BE CONFINED
TO THE FAR EASTERN PART OF THE AREA WITH SOME MINIMAL NEW
DEVELOPMENT POSSIBLE. MEANWHILE...STRONG WARMING OVER THE WESTERN
PART OF THE AREA MAY INCLUDE ENOUGH HEATING TO BREAK THE CAP FAR
WEST LATE THIS AFTERNOON AS THE DRYLINE GETS CLOSER. THIS IDEA WAS
DEEMED REASONABLE IN THE EARLIER FORECAST AND STILL LOOKS SO...BUT
AGAIN ACTIVITY SHOULD BE PRETTY SPARSE.
THE SURGE OF WARMING AND HEATING SHOULD TAKE TEMPERATURES UP TO THE
90S WEST...WITH INCREASINGLY HUMID 80S EAST. LOW CLOUDS WHICH WILL
BE PREVALENT IN AREAS EAST THIS MORNING SHOULD HEAT OUT AND
GENERALLY DECREASE LATE MORNING AND AFTERNOON.
FOR TONIGHT WILL KEEP SOME CHANCE OF STORMS FAR EAST WITH THE
STRONG INSTABILITY. OTHERWISE A WARM NIGHT IS IN STORE WITH LOW
TEMPERATURES WITHING A COUPLE DEGREES OF 70 EVERYWHERE.
.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 355 AM CDT SAT JUL 11 2015
HEAT AT THE FOREFRONT OF MID RANGE CONCERNS. CAPPED ENVIRONMENT WILL
BE IN PLACE WITH STRONG ELEVATED MIXED LAYER TRAPPING NEAR SURFACE
MOISTURE QUITE EFFECTIVELY ACROSS MUCH OF THE AREA THROUGH THE DAY.
LIKELIHOOD OF SOME CONVECTION TO OUR SOUTH AGAIN THIS EVENING WILL
ACT TO MODIFY ENVIRONMENT TO SOME DEGREE...AND SOUTH TO SOUTHEAST
FLOW NEAR THE SURFACE WILL REINFORCE PRESENCE OF BOUNDARY LAYER
MOISTURE INTO THE AFTERNOON FROM THE JAMES VALLEY EASTWARD.
EVENTUALLY...APPEARS AS IF THE SURFACE TROUGH WILL BE PUSHING INTO
THE JAMES VALLEY OR A BIT EAST BY LATE SUNDAY AFTERNOON...AND OTHER
THAN A BUFFER OF SLIGHTLY BETTER MIXING JUST TO THE EAST OF THIS...
MIXING WILL BE QUITE CHALLENGED BY THE STRONG INVERSION. AS A
RESULT...WILL PROBABLY NOT GET QUITE AS TOASTY FROM AROUND I29
EASTWARD...BUT STILL PLENTY WARM INTO THE LOWER 90S...WHILE AREAS
WEST OF THE TROUGH ARE LIKELY TO FIND A FEW SPOTS REACHING THE
CENTURY MARK...AS DEWPOINTS MIX GREATLY INTO THE 50S. EVEN WITH THE
SLIGHTLY LOWER TEMPERATURE EXPECTATIONS...DEWPOINTS WILL SOAR WELL
INTO THE 70S...AND WILL RESULT IN A LARGE AREA OF 100 TO 105 DEGREE
AFTERNOON HEAT INDEX. JAMES VALLEY LOCATIONS WILL HAVE THE WORST
EARLY AFTERNOON BEFORE START TO SEE MIXING LOWERING THE MOISTURE
CONTENT. WITH THE LONG PERIOD SINCE LAST EXTREME HEAT AND THE
NUMEROUS OUTDOOR ACTIVITIES ON THE WEEKEND...HAVE DECIDED TO ISSUE
HEAT ADVISORY FROM THE JAMES VALLEY EASTWARD THROUGH THE AFTERNOON
ON SUNDAY.
NOT TOTALLY IMPOSSIBLE TO FIND A ROGUE HIGH BASED THUNDERSTORM TO
START THE DAY...BUT SUCH A LOW CHANCE THAT HAVE KEPT CLEAR OF THE
FORECAST. OTHERWISE...WAVE WILL BEGIN TO PUSH ACROSS THE MEAN UPPER
RIDGE DURING SUNDAY AFTERNOON AND EVENING...AND START TO ERODE SOME
OF THE WARMEST AIR ALOFT. REALLY HARD TO PICTURE THERE BEING ENOUGH
LIFT TO BREAK RESIDUAL INVERSION EVEN AFTER FULL HEATING...WITH
CIN LIKELY IN THE 50-150 J/KG RANGE FOR MOST LOCATIONS. OUTSIDE
CHANCE THERE COULD BE A GOLDILOCKS LOCATION WHERE THE WEAKENING
CAP AND FORCING ARE JUST RIGHT...BUT AT THIS POINT NOT WORTH
CLUTTERING THE FORECAST WITH ISOLATED THREAT. HOWEVER...KEEP
AWARE...AS THERE IS MORE THAN ENOUGH POTENTIAL INSTABILITY TO MAKE
FOR A STRONGER STORM. PERHAPS A BIT BETTER CHANCE FOR THINGS TO
COME TOGETHER OVER THE NORTHEASTERN CWA CLOSEST TO THE UPPER
FORCING DURING THE EVENING...BUT SHOULD BE A PRETTY QUICKLY
CLOSING WINDOW AS STRONGER FORCING MOVES QUICKLY PAST AND DEEPER
DRYING ON WEST TO NORTHWEST FLOW SPREADS ACROSS THE AREA. NEAR
SURFACE WINDS WILL DECOUPLE AND ALLOW THE SURFACE TO RECOVER QUITE
A BIT IN THOSE FULLY MIXED AREAS...AND RETAIN SOME UPPER 60S
DEWPOINT VALUES IN THE SOUTHEAST.
ON MONDAY...AS SHOULD BE ANOTHER VERY WARM DAY...THE VERY HUMID
CONDITIONS WILL BE RELAXED SOMEWHAT OVER A GOOD PORTION OF THE
AREA...WITH HIGHEST READINGS EAST OF I 29 DURING THE MORNING HOURS.
DEEPER MIXING SHOULD TAKE DEWPOINTS INTO THE 50S WEST TO LOWER TO
MID 60S EAST DURING THE AFTERNOON...WITH WINDS AT 15 TO 25 MPH AT
TIMES. THE HEAT INDEX WILL AGAIN CLIMB INTO THE 90S. WILL HAVE TO
SEE IF WE GET ANOTHER INCREASE IN SMOKE BEHIND THE BOUNDARY AS IT
PUSHES SOUTHWARD SUNDAY NIGHT/MONDAY...AS COULD IMPACT TEMPS A
COUPLE DEGREES.
THE EXTENDED RANGE FROM TUESDAY THROUGH FRIDAY WOULD SEEMINGLY BE A
BIT MORE ACTIVE IN GENERAL...WITH RIDGE ACROSS THE NORTHERN
PLAINS...BREACHED PERIODICALLY WITH SYSTEMS COMING OUT OF THE WEST
TO SOUTHWEST FLOW ALOFT. A COMMON FEATURE IN MODELS IS WAVE AROUND
WEDNESDAY...AND HAVE MAINTAINED HIGHER PRECIP CHANCES WITH THIS
FEATURE. TEMPS SHOULD REMAIN FROM NORMAL TO SLIGHTLY ABOVE NORMAL...
BUT WILL HAVE TO WATCH TO SEE IF SLIGHTLY MORE AMPLIFIED SOLUTION IN
ECMWF COULD KEEP A BETTER BACKDOOR BOUNDARY AROUND MIDWEEK. ANOTHER
WAVE HAS PROXIMITY TO THE END OF THE FORECAST CYCLE...BUT
DRASTICALLY DIFFERING TIMING IN GREATER ENSEMBLE OF SOLUTIONS FOR
SURFACE REFLECTION. WATCHING FOR ANOTHER EASTWARD SURGE IN WARMER
AIR AHEAD OF THIS WAVE...WHICH COULD BE ON THE WAY FOR LATE WEEK.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT)
ISSUED AT 1051 PM CDT FRI JUL 10 2015
FOR THE 06Z TAF SET...STILL CONCERNED ABOUT MVFR DEVELOPMENT LATE
TONIGHT THROUGH MID MORNING SATURDAY DUE TO TRAPPED MOISTURE BELOW
THE THERMAL INVERSION. IN FACT EVEN CURRENTLY...THERE IS HIGHER
BASED STRATUS AROUND SIOUX CITY AND IN EASTERN NEBRASKA JUST
INSIDE THE VFR CATEGORY. SO THERE IS ABUNDANT LOW LEVEL MOISTURE.
NOT A HUNDRED PERCENT CONFIDENT IN THIS SCENARIO HOWEVER...SO
KEPT THE CEILINGS AS BROKEN AND CERTAINLY DID NOT WANT TO GO IFR
AT THIS TIME. AS FAR AS PRECIPITATION...CONTINUED TO LEAVE THE
TAF SET DRY BELIEVING THAT TSRA CHANCES ARE NOT WIDESPREAD ENOUGH
AT THIS TIME TO INCLUDE A MENTION IN THE TAFS.
&&
.FSD WATCHES/WARNINGS/ADVISORIES...
SD...HEAT ADVISORY FROM 1 PM TO 7 PM CDT SUNDAY FOR SDZ038>040-
053>056-059>062-065>071.
MN...HEAT ADVISORY FROM 1 PM TO 7 PM CDT SUNDAY FOR MNZ071-072-080-
081-089-090-097-098.
IA...HEAT ADVISORY FROM 1 PM TO 7 PM CDT SUNDAY FOR IAZ001>003-
012>014-020>022-031-032.
NE...HEAT ADVISORY FROM 1 PM TO 7 PM CDT SUNDAY FOR NEZ013-014.
&&
$$
SHORT TERM...
LONG TERM...CHAPMAN
AVIATION...MJ
AREA FORECAST DISCUSSION
NWS HOUSTON/GALVESTON TX
1212 PM CDT SAT JUL 11 2015
.DISCUSSION...
SEE 18Z AVIATION DISCUSSION.
&&
.AVIATION...
HI-RES ARW AND NMM SUPPORT MORE WIDESPREAD SHRA/TSRA THIS AFTN
THAN THE GFS/ECMWF. THE RAP IS SOMEWHERE IN BETWEEN SO THOUGHT
THE NAM/RAP WAS A GOOD COMPROMISE. PW VALUES WILL PEAK NEAR 2.00
INCHES THIS AFTN SO FEEL VCSH IS WARRANTED. WILL WATCH TREND AND
MAY HAVE TO CARRY THUNDER LATER THIS AFTN AS THERE APPEARS TO BE
ENOUGH INSTABILITY PRESENT TO GENERATE THUNDER. FCST SOUNDINGS
SHOW LESS POTENTIAL FOR LOW CLOUDS OVERNIGHT SO WENT GENERALLY
VFR. COULD GET SOME FOG AT KCXO PRIOR TO SUNRISE. VFR/DRY ON
SUNDAY WITH LIGHT WINDS. 43
&&
.PREV DISCUSSION... /ISSUED 1040 AM CDT SAT JUL 11 2015/
UPDATE...
MORNING UPPER AIR ANALYSIS SHOWED THE UPPER RIDGE HAD SPREAD
FARTHER WEST FROM EVENING OBSERVATIONS... WITH 1-2 DECAMETER
HEIGHT RISES SEEN OVER PARTS OF TEXAS...LOUISIANA...AND OKLAHOMA.
SIMILAR TO YESTERDAY... GOES SOUNDER IMAGERY SHOWS A PLUME OF 1.6
TO 1.8 INCH PRECIPITABLE WATER VALUES PUSHING INTO SOUTHEAST
TEXAS. THIS PLUME APPEARS TO HAVE PUSHED FARTHER INLAND THAN THIS
TIME YESTERDAY HOWEVER /ROUGHLY ALONG AND SOUTH OF THE 59
CORRIDOR NOW/ AND A FEW SHOWERS HAVE ALREADY DEVELOPED IN LIBERTY
AND CHAMBERS COUNTIES. AS DEEPER MOISTURE THIS MORNING SPREADS
INLAND... ADDITIONAL HEATING WILL CONTRIBUTE TO ISOLATED TO
SCATTERED SHOWER AND THUNDERSTORM DEVELOPMENT THROUGH EARLY
EVENING. CURRENT FORECAST HANDLES TRENDS WELL WITH NO MAJOR
CHANGES MADE.
HUFFMAN
PREV DISCUSSION... /ISSUED 404 AM CDT SAT JUL 11 2015/
DISCUSSION...
AREA RADAR THIS MORNING SHOWS A FEW ISO SHOWERS OFF THE COAST IN
THE GULF WHERE GOES SATELLITE DERIVED PRECIP WATER VALUES ARE
AROUND 1.8 INCHES. THIS HIGHER MOISTURE SHOULD CONTINUE TO MOVE
INLAND TODAY AND SUPPORT AT LEAST SOME ISO TO WIDELY SCT SHOWER
AND THUNDERSTORM ACTIVITY. UPPER LEVEL ANALYSIS AT 500MB SHOWS
594/595 DM RIDGE OVER MUCH OF THE NORTHERN GULF INCLUDING SE TX.
WHILE HIGHER MOISTURE AND DAYTIME HEATING SHOULD SUPPORT
THUNDERSTORM CHANCES...THINK AT LEAST SOME SUBSIDENCE WILL LIMIT
THE ACTIVITY. FORECAST WILL CONTINUE WITH 20 POPS FOR MUCH OF THE
AREA TODAY.
UPPER LEVEL RIDGE WILL EXPAND AND MOVE OVER MUCH OF TX AND S
PLAINS BY SUNDAY. THE RIDGE WILL REMAIN QUASI-STATIONARY OVER THE
S PLAINS AND TX FOR MUCH OF THE COMING WEEK. THE RIDGE MAY WEAKEN
SLIGHTLY FOR THE END OF THE COMING WEEK. HIGHER MOISTURE MAY ALSO
MOVE INTO THE REGION FROM THE GULF WHICH WILL BRING BACK A MENTION
OF THUNDERSTORM CHANCES FOR NEXT FRI/SAT.
TEMPERATURES FOR THE COMING WEEK WILL BE CLOSE TO CLIMO NUMBERS
OR MAYBE A COUPLE DEGREES HIGHER. HOUSTON IAH STILL HAS NOT
REACHED 95 DEGREES FOR A HIGH TEMPERATURE THIS YEAR. IT LOOKS LIKE
THAT MARK WILL BE REACHED SUN/MON. HIGH TEMPS IN THE MID 90S LOOK
REASONABLE FOR THE REST OF THE WEEK WITH LOW TEMPS IN THE
MID/UPPER 70S.
39
MARINE...
VERY LITTLE CHANGE TO ONGOING MARINE FCST. TYPICAL SUMMERTIME
PATTERN MOSTLY PREVAILING INTO NEXT WEEK WITH LIGHT TO
OCCASIONALLY MODERATE ONSHORE WINDS. SPEEDS OFFSHORE USUALLY A BIT
STRONGER AT NIGHT THAN DURING THE DAY. 47
&&
.PRELIMINARY POINT TEMPS/POPS...
COLLEGE STATION (CLL) 75 94 74 96 74 / 10 10 10 10 10
HOUSTON (IAH) 76 94 75 95 75 / 10 10 10 10 10
GALVESTON (GLS) 81 91 80 92 81 / 10 10 10 10 10
&&
.HGX WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
GM...NONE.
&&
$$
DISCUSSION...14
AVIATION/MARINE...43
AREA FORECAST DISCUSSION
NWS BLACKSBURG VA
731 PM EDT SUN JUL 12 2015
.SYNOPSIS...
A WEAK WARM FRONT WILL LIFT SLOWLY NORTHEAST TOWARD THE REGION
TONIGHT BEFORE PASSING TO THE NORTH LATER MONDAY INTO MONDAY NIGHT.
NORTHWEST FLOW ALOFT WILL ALLOW UPPER LEVEL DISTURBANCES TO SPILL
SOUTHEAST INTO THE AREA ALONG THE BOUNDARY THROUGH TUESDAY
RESULTING IN PERIODIC ROUND OF SHOWERS AND THUNDERSTORMS. A WEAK
COOL FRONT SHOULD DROP THROUGH THE REGION FROM THE NORTH BY MID
WEEK.
&&
.NEAR TERM /THROUGH MONDAY/...
AS OF 730 PM EDT SUNDAY...
STILL NO CLEAR MODEL CONSENSUS ON TIMING OR INTENSITY OF
PRECIPITATION...BUT SO FAR TODAY...ONLY RAIN SHOWERS HAVE IMPACTED
THE CWA. A CELL WEST OF TAZEWELL ONGOING CURRENTLY...IS THE FIRST
CELL I HAVE SEEN EVEN NEAR OUR CWA YET TO EXHIBIT ANY LIGHTNING.
MESO-SCALE MODELS HAVE VARYING DEGREES OF CONVECTION IMPACTING THE
AREA OVERNIGHT. THE HRRR BRINGS THE ACTIVITY CURRENTLY IN KENTUCKY
INTO OUR REGION IN A DIMINISHED STATE TOWARD MIDNIGHT. THE LOCAL
WRF KEEPS ALL SIGNIFICANT ACTIVITY WEST OF I-77...DROPPING THE
MOST INTENSE CONVECTION SOUTHWARD THROUGH EASTERN KY/EASTERN TN.
NCEP WRF MODELS IN BETWEEN...BUT AGAIN SHOW NOTHING SIGNIFICANT IN
OUR CWA TODAY OR TOMORROW. HAVE ADJUSTED POPS SOMEWHAT OVERNIGHT
INTO THE EARLY MORNING HOURS TO ACCOUNT FOR BETTER THREAT FOR
CONVECTION WEST OF I-77...LESS LEAST OF THE BLUE RIDGE. ONLY MINOR
ADJUSTMENTS TO T/TD NEEDED AT THIS TIME.
AS OF 355 PM EDT SUNDAY...
MODELS OFFERING SEVERAL DIFFERENT SOLUTIONS FOR TONIGHT AND
MONDAY...ESPECIALLY LOOKING AT WINDS...LOCATION OF PRECIPITATION
AND MAXIMUM TEMPERATURES ON MONDAY.
SATELLITE TOTAL PRECIPITABLE WATER PRODUCT AND VERTICAL PROFILERS
INDICATED PRECIPITABLE WATER VALUES HAVE RISEN TO AROUND 1.5
INCHES. WIDELY SCATTERED SHOWERS AND ISOLATED THUNDERSTORMS HAVE
DEVELOPED ON THE EASTERN EDGE OF A OLD MESOSCALE COMPLEX. SOME
GUIDANCE SUGGESTS THE CHANCE OF PRECIPITATION WILL EXTEND WELL
INTO THE EASTERN COUNTY WARNING AREA TONIGHT.
ANOTHER CLUSTER OF SHOWERS AND THUNDERSTORMS WILL DEVELOP UPSTREAM
TONIGHT WITH MORE PRECIPITATION IN THE FORECAST AREA MONDAY
AFTERNOON. BUT OVERALL INSTABILITY AND SHEAR IS MARGINAL. BELIEVE
BEST PROBABILITY FOR PRECIPITATION AND HIGHEST RAINFALL AMOUNTS
WILL BE ALONG AND WEST OF I-77 THROUGH MONDAY AFTERNOON.
WITH HIGHER SURFACE DEW POINTS BACK IN THE AREA...MINIMUM TEMPERATURES
WILL BE MILDER TONIGHT THAN ON SUNDAY MORNING. THE AMOUNT OF CLOUD
COVER IN THE MORNING AND PRECIPITATION IN THE AFTERNOON WILL
IMPACT THE TEMPERATURES ON MONDAY. STAYED CLOSER TO BIAS CORRECTED
MAV GUIDANCE FOR TONIGHT AND ON MONDAY.
&&
.SHORT TERM /MONDAY NIGHT THROUGH WEDNESDAY NIGHT/...
AS OF 230 PM EDT SUNDAY...
WEATHER SCENARIO REMAINS QUITE COMPLICATED WITH TIMING OF FEATURES
ACROSS THE AREA WITHIN A VERY MOIST/UNSTABLE ENVIRONMENT WHILE LIMITED
VIA WESTERLY WINDS ALOFT AND ONLY WEAK SURFACE FEATURES UNTIL LATE
TUESDAY. LATEST SUITE OF SOLUTIONS SUGGEST THAT MAY INIT BETWEEN UPPER
WAVES MONDAY EVENING AS A LEAD SHORTWAVE EXITS THE PIEDMONT AHEAD OF
PERHAPS ANOTHER UPSTREAM VORT/MCS THAT LOOKS TO DIVE SE TOWARD THE
SOUTHERN APPALACHIANS BY EARLY TUESDAY. APPEARS THIS IMPULSE MAY ACT TO
ENHANCE CONVERGENCE ALONG THE WESTERN SLOPES MONDAY EVENING WITH SOME
OF THIS POSSIBLY JETTING ACROSS THE SW OVERNIGHT ALONG THE RETREATING
WARM FRONT. THIS COULD PROVIDE A TIGHT GRADIENT TO POPS WITH LITTLE OUT
EAST AFTER ANY EVENING COVERAGE FADES WITH A COUPLE ROUNDS POSSIBLE OUT
WEST WHERE FOR NOW WILL KEEP OVERALL LIKELY POPS IN PLACE.
STRONG UPPER TROUGH FOR JULY WILL DIG SE OUT OF THE GREAT LAKES TUESDAY
BEFORE SLIDING TO NEAR THE DELMARVA ON WEDNESDAY. THIS WILL PUSH THE
TRAILING SHORTWAVE TROUGH AXIS SE TOWARD THE REGION LATE IN THE DAY
TUESDAY...AIDED BY INCREASING WINDS ALOFT AND HIGH INSTABILITY...
PROVIDED CAN GET ENOUGH HEATING THROUGH RESIDUAL DEBRIS CLOUDS...AND
ISOLATED SHOWERS ESPCLY WEST. HOWEVER GUIDANCE SHOWS A VERY PRONOUNCED
WEST/NW TRAJECTORY JUST ABOVE THE BOUNDARY LAYER WHICH WOULD TEND TO
FOCUS MOST BANDED CONVECTION OVER THE WEST AS THE NW FLOW CONVEYOR BELT
SHOULD BE ABOUT OVERHEAD BY THEN. LEE TROUGH ALSO QUITE STRONG BY LATER
TUESDAY WHICH IN CONJUNCTION WITH A SURFACE LOW FORMING IN RESPONSE TO
THE 5H SYSTEM MAY CAUSE A QUICK JUMP TO THE EAST OF THE AREA LATE IN
THE DAY. SINCE THIS LOOKS QUITE REALISTIC PENDING TIMING...WILL ADJUST
POPS TO HIGHER LIKELYS FAR WEST TUESDAY PER HIGH FORECAST THETA-
E/DIVERGENCE ALOFT...AND GO HIGHER CHANCE EAST WITH LEAST COVERAGE BLUE
RIDGE GIVEN DOWNSLOPE INTO TUESDAY NIGHT. THIS APPEARS TO BE THE PERIOD
FOR MORE WIDESPREAD SEVERE SO KEEPING IN THE HWO PER GOING SPC
OUTLOOKS.
AREA WILL SPILL UNDER THE COLD POOL ALOFT WITH THE 5H LOW TO THE NE ON
WEDNESDAY WITH QUITE A BIT OF SUPPORT ROTATING AROUND THIS FEATURE TO
KEEP DECENT LIFT GOING THROUGH LATE WEDNESDAY. THINK MORE OF A
NORTHERLY TRAJECTORY SHOULD TEND TO LIMIT SHRA ACROSS THE FAR SOUTH BUT
APPEARS COULD SEE MORE WIDESPREAD WEAKER SHRA/ISOLATED TSRA WEDNESDAY
BEFORE DRIER AIR ALOFT ADVECTS IN AND ENDS THE SHOWER THREAT DURING THE
EVENING. OVERALL PLAN TO KEEP POPS ON THE CHANCE SIDE PENDING LATER
RUNS SINCE THE DEGREE OF RESIDUAL MOISTURE RATHER UNCERTAIN FOR NOW.
KEPT TEMPS ON THE WARM SIDE OF MOS INTO TUESDAY NIGHT WITH LOW AND EVEN
MID 90S POSSIBLE EAST TUESDAY IF CLOUDS/SHRA ARE LESS. SHOULD BE A BIT
COOLER UNDER MORE CLOUDS...SHOWERS AND NORTHERLY FLOW WEDNESDAY WITH
MOSTLY 80S EXCEPT PERHAPS ONLY SOME 70S FOR HIGHS WEST.
&&
.LONG TERM /THURSDAY THROUGH SUNDAY/...
AS OF 100 PM EDT SUNDAY...
5H HEIGHTS WILL BUILD EAST ACROSS THE REGION THROUGH MUCH OF THE PERIOD
AS THE LARGE UPPER HIGH OVER THE SOUTHERN PLAINS NUDGES EASTWARD INTO
NEXT WEEKEND. THIS SHOULD MEAN A MORE DIURNALLY DRIVEN LESS ORGANIZED
PATTERN TO CONVECTION AS FOCUS SHIFTS TO MORE OUTFLOW DRIVEN SHRA/TSRA
PERHAPS AIDED BY FAINT SHORTWAVE ENERGY PASSING AROUND THE RIDGE IN THE
WEST/NW FLOW ALOFT. INITIALLY SHOULD BE IN THE WAKE OF THE FRONT TO THE
SOUTH AND THE UPPER SYSTEM TO THE EAST THURSDAY...WITH WEAK HIGH
PRESSURE TO THE NORTH BRINGING A PERIOD OF WEAK SUBSIDENCE THURSDAY
INTO THURSDAY NIGHT INCLUDING ONLY ISOLATED CONVECTION AT BEST.
MOISTURE SHOULD START TO MAKE A SLOW RETURN FRIDAY AND ESPCLY SATURDAY
AS THE WEAK FRONT SHIFTS BACK NORTH AND WEAK RETURN FLOW DEVELOPS. THIS
LOOKS TO BRING SCATTERED NATURE POPS BACK BY FRIDAY AFTERNOON WITH
HIGHER CHANCES SATURDAY UNDER BETTER PWATS. NEXT WEAK UPPER TROUGH AND
ITS ASSOCIATED COOL FRONT APPROACHES ON SUNDAY WHILE PRECEDED BY MORE
WESTERLY FLOW. THIS SUGGESTS BEST CHANCE POPS WEST/NORTH AND LESS OUT
EAST DESPITE DEEP MOISTURE AND GOOD HEATING.
A SLIGHTLY COOLER/DRIER PERIOD THURSDAY/THURSDAY NIGHT LOOKS TO REBOUND
BACK TO HIGHS OF 85-90 WEST AND LOW/MID 90S EAST BY NEXT WEEKEND UNDER
WESTERLY FLOW AND PROGGED 85H TEMPS OF +22-23C.
&&
.AVIATION /00Z MONDAY THROUGH FRIDAY/...
AS OF 720 PM EDT SATURDAY...
A PIPE LINE OF SHOWERS WILL CONTINUE TO TRACK OVER THE AREA INTO
EARLY MORNING MONDAY. THESE LINES OF SHOWERS ARE ORIENTED FROM
NORTHWEST TO THE SOUTHEAST AND ARE NARROW. ONE OF THE MOST SOLID
LINES IS FIXED OVER KBKW-KBCB-KMTV. LIGHT SHOWERS WILL REMAIN OVER
THIS AREA THIS EVENING. THIS LINE MAY DRIFT NORTH OVERNIGHT...SITTING
OVER KLWB-KROA BY MORNING...BUT A TOUGH CALL FOR NOW AS THIS LINE
APPEARS STATIONARY. FOR THE MOST PART...WILL CALL FOR LIGHT SHOWERS
WEST OF THE BLUE RIDGE AND VICINITY SHOWERS EAST. CEILINGS MAY
ALSO LOWER THROUGH THE NIGHT TO MVFR...ESPECIALLY AT KBLF. THIS
LOW CONFIDENCE ENVIRONMENT WILL BEST BE HANDLED WITH AMENDMENTS
RATHER THAN A VERY DETAILED HOUR BY HOUR SET OF TAFS.
EXTENDED AVIATION DISCUSSION...
MONDAY AND TUESDAY APPEAR TO OFFER THE BEST CHANCE FOR WIDESPREAD
DEEP CONVECTION...SOME OF WHICH COULD BE STRONG TO SEVERE...WITH
AN ACTIVE NORTHWEST/BAROCLINIC FLOW IN PLACE ALONG THE NORTHEAST
SIDE OF A STRONG SUBTROPICAL RIDGE ANCHORED IN THE SOUTHERN
PLAINS. ONE OR MORE CONVECTIVE COMPLEXES APPEAR LIKELY WITHIN THIS
TIME FRAME...BUT EXACT PLACEMENT AND TIMING IS NOT POSSIBLE THIS
FAR OUT.
MORE TYPICAL SUMMERTIME CONDITIONS RETURN FOR THE LATER
HALF OF THE WEEK WITH EARLY MORNING FOG/LOW CLOUDS IN THE USUAL
SPOTS...KLWB/KBCB/KLYH...AND ISOLATED TO SCATTERED AFTERNOON/EVENING
SHOWERS AND THUNDERSTORMS. OVERALL...CIGS AND VSBYS SHOULD BE VFR
MUCH OF THE TIME PERIOD.
&&
.RNK WATCHES/WARNINGS/ADVISORIES...
VA...NONE.
NC...NONE.
WV...NONE.
&&
$$
SYNOPSIS...JH/PM
NEAR TERM...AMS/RAB
SHORT TERM...JH
LONG TERM...JH
AVIATION...AMS/PM/RCS
AREA FORECAST DISCUSSION
NWS MILWAUKEE/SULLIVAN WI
932 PM CDT SUN JUL 12 2015
.UPDATE...STILL EXPECT UPSTREAM SEVERE/NEAR SEVERE CONVECTION OVER
CENTRAL MN TO TAKE A TURN SOUTHEAST AND MOVE ALONG INSTABILITY
GRADIENT DRAPED ACROSS SE MN/ERN IA/WRN WI. UPSTREAM SHORT WAVE
TROF OVER WRN MN AND INCREASING UPPER LEVEL DIVERGENCE FROM LEFT
EXIT REGION OF UPPER JET SHOULD CARRY CONVECTION ACROSS MUCH OF
SRN WI LATE TONIGHT INTO EARLY MON. THINKING HRRR AND NAMNEST HAVE
BETTER HANDLE ON CONVECTION AS NAM HAD GOOD HANDLE ON CONVECTIVE
INTIATION LOCATION WITH REGARDS TO MOISTURE FLUX CONVERGENCE INTO
WEST CENTRAL MN LATE IN THE AFTN. WRF-ARW AND WRF-NMM TOO FAR
NORTH WITH ON-GOING CONVECTION AND LIKELY TO BE TOO SLOW. WILL
CONTINUE TO FOCUS ON PERIOD FROM 09Z THROUGH 13Z. NOT RULING OUT
ISOLD TO SCT ACTIVITY DEVELOPING AHEAD OF MAIN LINE DUE TO
INCREASING LOW LEVEL THETA-E ADVECTION AS WELL.
&&
.AVIATION/06Z TAFS/...INCREASING LOW LEVEL AND MOISTURE
CONVERGENCE LIKELY TO CAUSE AREAS OF STRATUS TO PERSIST THROUGH
THE NIGHT. LATEST 11-3.9 MICRON IMAGERY SHOWING SOME INCREASE IN
WRN CWA. CIG HEIGHTS FLIRTING WITH 3K FEET SO WL LIKELY HAVE TO
HAVE SOME MVFR CIGS PRIOR TO UPSTREAM CONVECTION AFFECTING TAF
SITES...ESTIMATED MAINLY BETWEEN 09Z AND 13Z.
&&
.MARINE...LATEST MODIS ESTIMATE OF LAKE SURFACE TEMP MEASURED
TEMPS IN THE 63 TO 66 RANGE OFFSHORE. WITH HIGHER DEWPOINT AIR
EXPECTED TO SPREAD IN LATER TONIGHT AND MONDAY...EXPECTED PATCHY
FOG TO TRANSITION TO MORE WIDESPREAD FOG LATE TONIGHT OR MONDAY.
EXPECTED SHOWERS AND STORMS LATE TONIGHT LIKELY TO REDUCE THE FOG
FOR A TIME BUT MORE LIKELY TO DEVELOP MONDAY MORNING.
&&
.PREV DISCUSSION... /ISSUED 423 PM CDT SUN JUL 12 2015/
SHORT TERM...
TONIGHT AND MONDAY MORNING... FORECAST CONFIDENCE MEDIUM.
THUNDERSTORMS DEVELOPING THIS AFTERNOON OVER EASTERN ND/ WESTERN MN
WILL EXPAND INTO BOWING LINE SEGMENTS AND EVENTUALLY CROSS SOUTHERN
WI...PROBABLY BETWEEN 4 AM AND 8 AM. THERE IS STILL SOME MINOR MODEL
VARIABILITY MEANING THERE IS STILL SOME UNCERTAINTY ABOUT WHERE THE
STRONGEST STORMS WILL TRACK. SPC IS FAVORING THE TRACK WHERE THE
STORMS DIVE SOUTHEAST THROUGH THE TWIN CITIES AND SOUTHWEST WI...
CLOSEST TO THE INSTABILITY GRADIENT. THIS IS A MORE COMMON
OCCURRENCE WITH STORMS. THE OTHER POSSIBILITY IS THAT THE BULK OF
THE STORMS COULD TRACK DUE EAST WITH THE NORTHERN EDGE OF THE MID
LEVEL SHORTWAVE AND CROSS CENTRAL WI.
BOTH SCENARIOS IMPACT SOUTH CENTRAL AND SOUTHEAST WI WITH
THUNDERSTORMS OVERNIGHT INTO MONDAY MORNING... SO INCREASED THE POPS
AND KEPT THE MENTION OF CHANCE FOR SEVERE STORMS WITH DAMAGING WIND.
ELEVATED CAPE WILL BE OVER 4000 J/KG WITH MODERATE BULK SHEAR TO
SUPPORT A PERSISTENT DAMAGING WIND THREAT.
MANY OF THE MODELS DELAY THE SYSTEM REACHING SOUTHERN WI UNTIL 09Z
OR LATER. THEY ARE ALSO SHOWING CONVECTION DEVELOPING AHEAD OF THE
MAIN STORM COMPLEX DUE TO LOW LEVEL WARM AIR ADVECTION. KEPT CHANCE
OF THUNDERSTORMS OUT AHEAD OF THE MAIN LINE FOR THE FORECAST. THERE
IS A HAIL THREAT FOR ANY ORGANIZED STORMS THAT DEVELOP.
MONDAY AFTERNOON... FORECAST CONFIDENCE MEDIUM.
WE ARE KEEPING OUR EYES ON THE POTENTIAL FOR SEVERE WEATHER MONDAY
AFTERNOON IN SOUTH CENTRAL AND SOUTHEAST WI. THE 12Z NAM AND GFS ARE
SHOWING HIGH CAPE WITH THE SURFACE WARM FRONT IN THE VICINITY. IF
CONVECTION CAN DEVELOP... STORMS SHOULD BE SUPERCELLULAR AND QUICKLY
EVOLVE INTO BOWING LINE SEGMENTS. SOME OF THE MESO MODELS DEVELOP
THE STORMS IN CENTRAL WI BUT THE SYNOPTIC MODELS SHOW DEVELOPMENT IN
SOUTHEAST WI.
SPC UPGRADED THE SOUTH HALF OF THE MKX AREA TO AN ENHANCED RISK FOR
THIS EVENT. THE SEVERE POTENTIAL WILL BE HIGHLY DEPENDENT ON HOW THE
CONVECTION EVOLVES OVERNIGHT INTO MONDAY MORNING. STAY TUNED.
MONDAY NIGHT AND TUESDAY...FORECAST CONFIDENCE MEDIUM
THERE WILL BE A CHANCE OF ONGOING THUNDERSTORMS MAINLY SOUTHEAST
EARLY DURING THE EVENING. MIXED LAYER CAPE ON THE GFS WILL STILL
BE AROUND 2200 JOULES/KG WITH ZERO TO 6 KM SHEAR AROUND 35 KNOTS.
THE NAM DIMINISHES THE THUNDERSTORM CHANCES SOONER...BEING MAINLY
SOUTH OVER NORTHERN ILLINOIS BY MONDAY EVENING.
THE MID LEVELS DRY BY MID EVENING AS LOW AND MID LEVELS WINDS
BECOME WEST.
THE UPPER FLOW BECOMES MORE NORTHWEST AFTER A WEAK UPPER LEVEL
SHORTWAVE EXITING THE SOUTHEAST EARLY TUESDAY MORNING...ALONG WITH
A WEAKENING 85 KNOT 250 MB JET ACROSS ILLINOIS THAT SAGS A BIT
SOUTH.
THE GFS SHARPENS THE 700 MB MID LEVEL SHORTWAVE AFTER IT EXITS THE
SOUTHEAST EARLY TUESDAY MORNING. THE 700 MB RH DRIES TUESDAY BUT
850 MB LEVELS REMAIN MOIST WITH 850 MB DEWPOINTS NEAR 16 CELSIUS
WITH SURFACE DEW POINTS IN THE UPPER 60S.
A BACKDOOR COLD FRONT SHOULD REACH EAST SECTIONS AND SPREAD INLAND
DUE TO THE COOLER AIR OVER LAKE MICHIGAN.
AFTERNOON CAPES RANGE FROM 1200 NORTHEAST TO 2000 JOULES/KG.
LOW LEVEL LAPSE RATES ARE STEEP...AND THERE IS ONLY A MINIMAL
CAP. THE GFS NAM AND 00Z ECMWF SHOW LIGHT TO MODERATE
PRECIPITATION AMOUNTS. A STRONG TRIGGER IS LACKING...BUT SCATTERED
THUNDERSTORMS ARE A POSSIBILITY TUESDAY.
TUESDAY NIGHT AND WEDNESDAY...FORECAST CONFIDENCE MEDIUM
THE MID/UPPER LEVEL RIDGE PUSHES INTO THE UPPER MISSISSIPPI
VALLEY. THE 700 MB FLOW IS FROM THE NORTHWEST BUT AS THE 850 MB
RIDGE MOVES TOWARD LAKE MICHIGAN...A LIGHT SOUTH FLOW BEGINS
TOWARD EVENING.
HIGH PRESSURE WILL EXTEND ACROSS THE NORTHERN GREAT LAKES TUESDAY
NIGHT THEN MOVE TOWARD THE EASTERN GREAT LAKES WEDNESDAY AFTERNOON.
LOW DEWPOINTS IN THE 50S...AND EVEN SOME MID 40S NORTH AREAS WILL
BEGIN TO RISE DURING THE AFTERNOON...OVER INLAND AREAS.
LONG TERM...
THURSDAY AND FRIDAY...FORECAST CONFIDENCE MEDIUM
THE GFS AND 00Z ECMWF HAVE A FAIRLY ZONAL FLOW WITH ONE OR TWO
WEAK SHORTWAVES MOVING ACROSS WISCONSIN AS A STRONG TROUGH DROPS
INTO THE NORTHWEST U.S.
AS THE SURFACE HIGH OVER THE UPPER GREAT LAKES RECEDES TO
THE EAST...A RETURN FLOW RESULTS IN A CHANCE OF THUNDERSTORMS
THURSDAY AFTERNOON AND THURSDAY NIGHT ON THE GFS AND 00Z
ECMWF...AS A SURFACE TROUGH MOVES ACROSS SOUTHERN WISCONSIN.
SATURDAY...FORECAST CONFIDENCE MEDIUM
BOTH THE GFS AND ECMWF PUSH A MID LEVEL TROUGH INTO THE NORTHERN
ROCKIES AND NORTHERN PLAINS. THE ECMWF IS A LITTLE QUICKER WITH A
STRONGER DOWNSTREAM SHORTWAVE LINGERING NORTH OF THE EASTERN
GREAT LAKES.
A SURFACE TROUGH MOVES ACROSS THE AREA WITH A CHANCE OF
THUNDERSTORMS AGAIN LATER SATURDAY AND SATURDAY NIGHT.
SUNDAY...FORECAST CONFIDENCE MEDIUM
THE 00Z ECMWF CUTS OFF A LOW OFF THE PACIFIC NORTHWEST WITH THE
MAIN TROUGH MOVING ACROSS SOUTH CENTRAL CANADA. THE GFS HAS MORE
OF A TROUGH OVER THE NORTHERN ROCKIES.
AVIATION/00Z TAFS/...
THE MOIST BOUNDARY LAYER IS KEEPING CLOUD BASES IN THE MVFR RANGE
FROM 2 TO 3 KFT THIS AFTERNOON. I AM EXPECTING A PERIOD OF MOSTLY
CLEAR SKIES IN SOUTHERN WI AFTER SUNSET THIS EVENING.
VFR CONDITIONS EXPECTED UNTIL STORMS ARRIVE AFTER ABOUT 08 OR 09Z
MONDAY. WE ARE EXPECTING A LINE OF STRONG STORMS TO TRACK OUT OF MN
AND HEAD SOUTHEAST THROUGH SOUTHERN WI EARLY MONDAY MORNING. THIS IS
MAINLY A STRAIGHT-LINE WIND EVENT AND WE COULD SEE DAMAGING WIND
WITH THE LINE. ANY OF THE HEAVIER STORMS WILL HAVE MVFR AND IFR
CONDITIONS AT LEAST FOR A TIME. THERE COULD BE SOME ISOLATED STORMS
AHEAD OF THE MAIN LINE TONIGHT AFTER MIDNIGHT.
DEPENDING ON HOW QUICKLY OUR ATMOSPHERE CAN RECOVER DURING THE DAY
MONDAY... ANOTHER ROUND OF THUNDERSTORMS IS POSSIBLE MONDAY
AFTERNOON/EVENING AND THESE COULD BE SEVERE.
MARINE...
AREAS OF FOG DEVELOPED OVER PORTIONS OF THE NEARSHORE WATERS...
APPARENT ON WEBCAMS AND SOMEWHAT ON VISIBLE SATELLITE IMAGERY.
VISIBILITY WILL BE 1 MILE OR LESS AT TIMES. THE CHANCE FOR FOG WILL
PERSIST THROUGH MONDAY NIGHT WITH WARM AND MOIST AIR OVER THE REGION.
&&
.MKX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
LM...NONE.
&&
$$
UPDATE...MBK
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
1247 PM CDT SAT JUL 11 2015
.UPDATE...
ISSUED AT 1146 AM CDT SAT JUL 11 2015
HAVE BEEN WORKING THROUGH THE MORNING AT TRYING TO KEEP AHEAD OF
THE WEATHER. SHORTWAVE TROUGH ENERGY UPSTREAM MOVING AT THE AREA
IS PROVIDING ENOUGH LIFT WITH WEAK WARM ADVECTION AND MINOR MUCAPE
/250 J/KG/ OF INSTABILITY TO POP SHOWERS AND ISOLATED THUNDER.
BELIEVE THE AREA WILL CONTINUE TO MOVE EAST THROUGH THE DAY AND
FEEL SOME DIMINISHMENT MAY OCCUR AS IT DOES. BEHIND THE
WAVE...BELIEVE MANY HOURS OF DRY WEATHER WILL HOLD WITH LITTLE
FORCING UNTIL AFTER MIDNIGHT. HAVE LOWERED THE RAIN CHANCES BEHIND
THE WEATHER UNTIL LATER TONIGHT...BUT AM STILL ASSESSING LATER
INTO THE OVERNIGHT.
SUBSTANTIAL CLOUD AND RAIN HAS CAUSED TEMPERATURES TO REALLY STAY
COOL. HAVE LOWERED HIGHS TODAY SOME...BUT SOME LATE SUN COULD POP
THEM UP FAST. SO...HAVE KEPT THE AFTERNOON COOL WITH A LATE JUMP.
RAIN RATES ARE PRETTY IMPRESSIVE WITH SUCH LITTLE CAPE. THESE
LITTLE SHOWERS ON RADAR ARE CAUSING SOME GOOD DOWNPOURS. 50DBZ
CORE NEAR AUTIN MN CAUSED 0.75 INCHES OF RAIN IN A SHORT AMOUNT OF
TIME. HERE COMES THE HIGHER PRECIPITABLE WATER WITH 1.5 INCH
&&
.SHORT TERM...(TODAY THROUGH MONDAY)
ISSUED AT 339 AM CDT SAT JUL 11 2015
REGIONAL RADARS THIS MORNING SHOWING SOME CONVECTION THIS MORNING
OVER NORTHERN MISSOURI WITH ANOTHER AREA OF CONVECTION OVER
EASTERN NEBRASKA. THIS ACTIVITY IS NORTH OF A WARM FRONT THAT
EXTENDS ACROSS NORTHERN KANSAS AND MISSOURI AND AHEAD OF A WEAK
TROUGH OF LOW PRESSURE FROM KANSAS INTO NORTH DAKOTA. WATER VAPOR
SATELLITE SHOWS ONE SHORT WAVE TROUGH OVER NEBRASKA AND KANSAS
WITH ANOTHER OVER NORTH DAKOTA. THE TREND IN THE 11.00Z MODELS AND
11.03Z RAP IS FOR THE WAVE OVER NEBRASKA AND KANSAS TO FLATTEN
OUT AS IT MOVES NORTHEAST INTO THE TOP PART OF THE RIDGE AXIS OVER
THE CENTRAL PART OF THE COUNTRY. THE WAVE OVER NORTH DAKOTA WILL
ALSO CONTINUE TO MOVE NORTHEAST INTO SOUTHERN CANADA THROUGH THE
DAY. THE SURFACE WARM FRONT SHOULD LIFT SLOWLY TO THE NORTH WITH A
GENERAL MODEL CONSENSUS OF IT REACHING ABOUT THE IOWA/MISSOURI
BORDER. THIS WILL KEEP THE BEST MOISTURE TRANSPORT WELL SOUTH OF
THE AREA TODAY AND SHOULD KEEP MOST OF THE RAIN TO THE SOUTH AS
WELL. THE MESO MODELS SEEMED TO HAVE LATCHED ON TO THIS AS WELL
WITH THE 11.00Z CR-NAM NEST...HI-RES ARW AND NMM KEEPING THE AREA
DRY WHILE THE 11.00Z NAM12 AND 11.05Z HRRR STILL TRY TO BRING THE
REMAINS OF SOME DEVELOPING CENTRAL IOWA CONVECTION INTO THE
SOUTHERN SECTIONS FOR THIS MORNING. BASED ON ALL THESE
SOLUTIONS...HAVE TRENDED THE RAIN CHANCES DOWN FOR TODAY WITH
ABOUT A 20 PERCENT CHANCE ACROSS THE NORTH TO AT MOST A 40 PERCENT
CHANCE IN THE SOUTH. THESE COULD STILL BE TOO HIGH AS IT COULD END
UP BEING TOTALLY DRY NORTH OF THE IOWA/MINNESOTA BORDER.
UPPER LEVEL HEIGHTS SHOULD BUILD A LITTLE BIT OVER THE REGION
TONIGHT AS THE SHORT WAVE TROUGHS MOVE OFF TO THE EAST. THE WARM
FRONT WILL CONTINUE TO LIFT SLOWLY NORTH TAKING ON A MORE
NORTHWEST TO SOUTHEAST ORIENTATION FROM A DEVELOPING AREA OF LOW
PRESSURE OVER NORTH DAKOTA INTO CENTRAL ILLINOIS. THE NAM REALLY
RAMPS UP THE MOISTURE TRANSPORT INTO THIS BOUNDARY AROUND 06Z
SUNDAY AND BREAKS OUT CONVECTION NORTH OF THE BOUNDARY AND ACROSS
THE AREA. THE 11.00Z GFS SOMEWHAT HINTS AT THIS AS WELL WHILE THE
11.00Z ECMWF KEEPS THE BOUNDARY FARTHER SOUTH AND MOST OF THE RAIN
TO THE SOUTH AS WELL. THE HI-RES NMM IS SIMILAR TO THE NAM WHILE
THE HI-RES ARW IS COMPLETELY DRY FOR TONIGHT. CONCERNED THAT
THE NAM IS TOO STRONG WITH THE MOISTURE TRANSPORT TONIGHT AND WILL
ONLY CARRY A GENERAL 30 TO 40 PERCENT CHANCE ACROSS THE AREA.
THE REAL ACTION AND BEST CHANCES FOR RAIN MAY COME SUNDAY NIGHT. A
SHORT WAVE TROUGH IS EXPECTED TO COME OUT OF THE WEAKENING UPPER
LEVEL LOW CURRENTLY OVER OREGON AND NEVADA. THIS WAVE SHOULD TOP
THE UPPER LEVEL RIDGE AND THEN SLIDE SOUTHEAST ACROSS THE AREA
SUNDAY NIGHT. THE GFS SUGGESTS THIS WAVE WILL PRODUCE SOME
MODERATE PV ADVECTION IN THE 500-300 MB LAYER AS IT COMES ACROSS.
THIS LIFT SHOULD BE AIDED BY SOME JET DYNAMICS FROM THE LEFT EXIT
REGION OF THE 300 MB JET AS THIS COMES IN WITH THE SHORT WAVE
TROUGH. THE WARM FRONT SHOULD CONTINUE TO EDGE NORTH EXTENDING
FROM EASTERN NORTH DAKOTA INTO ILLINOIS WITH THE GFS SHOWING WEAK
TO MODERATE FRONTOGENESIS IN THE 1000-850 MB LAYER NORTH OF THE
FRONT. AS THE SHORT WAVE TROUGH APPROACHES...A CONVECTIVE COMPLEX
SHOULD FROM LATE SUNDAY AFTERNOON OVER THE EASTERN DAKOTAS AND
THEN SLIDE SOUTHEAST THROUGH THE NIGHT ALONG AND NORTH OF THE WARM
FRONT. THERE SHOULD STILL BE AMPLE CAPE AVAILABLE FOR THE STORMS
TO WORK WITH AS THEY MOVE INTO THE AREA. THE GFS SUGGESTS UP TO
2500 J/KG OF ML CAPE SUNDAY EVENING ONLY DROPPING OFF TO 1500 J/KG
DURING THE OVERNIGHT HOURS. UP TO 40 KNOTS OF SHEAR SHOULD MOVE IN
AHEAD OF THE SHORT WAVE TROUGH WITH THIS BEING PRIMARILY IN THE
0-3 KM LAYER. THIS WILL PRESENT THE OPPORTUNITY FOR A NOCTURNAL
MCS TO ROLL ACROSS THE AREA WITH A SEVERE WIND THREAT. HAIL DOES
NOT LOOK TO BE MUCH OF THREAT WITH WARM CLOUD DEPTHS ON THE ORDER
OF 3.5 TO 4 KM...BUT THERE SHOULD BE SOME GOOD RAINFALL RATES AND
LOCALLY HEAVY RAINS.
.LONG TERM...(MONDAY NIGHT THROUGH FRIDAY)
ISSUED AT 339 AM CDT SAT JUL 11 2015
THE UPPER LEVEL RIDGE SHOULD BRIEFLY BUILD BACK OVER THE REGION
EARLY IN THE WEEK BEFORE FLATTENING OUT WITH ZONAL FLOW OVER THE
UPPER MIDWEST. THIS PATTERN LOOKS TO BE A DIRTY FLOW WITH THE
POTENTIAL FOR SEVERAL SHORT WAVE TROUGHS TO BE EMBEDDED IN THE
FLOW AND COME ACROSS THE REGION. DECENT AGREEMENT IN TIMING OF A
WAVE FOR WEDNESDAY BETWEEN THE ECMWF AND GFS...BUT DIFFERENCES IN
STRENGTH WITH THE GFS BEING STRONGER. AFTER THAT...CONSIDERABLE
DIFFERENCES IN HOW AN UPPER LEVEL LOW COMING ACROSS SOUTHWEST
CANADA IS HANDLED. THE GFS OPENS THIS SYSTEM UP AND BRINGS IT
TOWARD THE AREA BY THE END OF THE WEEK WHILE THE ECMWF KEEPS IT AS
A CLOSED LOW HOLDING IT BACK WITH RIDGING OVER THE REGION. WITH
ALL THE UNCERTAINTY...WILL STAY WITH GENERAL 20 TO 40 PERCENT
CHANCES THROUGH THE PERIOD.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON)
ISSUED AT 1247 PM CDT SAT JUL 11 2015
EXPECT AN IMPROVING TREND OVER THE NEXT HOURS AT KRST AS IFR CIGS
WILL GIVE WAY TO MVFR. THERE WILL BE THE POSSIBILITY OF MVFR IF
SOME SHOWERS WORK INTO KLSE BUT LATEST 60 MINUTES OF RADAR
INDICATE A DIMINISHING TREND.
OVERNIGHT ABUNDANT LOW LEVEL MOISTURE AND CLEAR SKIES...IN
CONCERT WITH COOLER HIGHS TODAY UNDER THE CLOUDS...WILL SET UP THE
DEVELOPMENT OF LOW CLOUDS AND FOG AS THE OVERNIGHT PROGRESSES.
THIS IS ALL NORTHEAST OF A WARM FRONT WHICH WILL BE LOCATED NEAR
I-35. THIS CLOUD AREA WILL BE WIDESPREAD ACROSS THE
REGION...ANCHORED IN WI. THE CLOUDS ARE EXPECTED TO LIFT AND MIX
OUT THROUGH THE MORNING HOURS SUNDAY FROM WEST TO EAST.
CONFIDENCE IN THE MORNING IFR CLOUD FORECAST IS MEDIUM. THERE
COULD BE SOME LOWER VSBYS SHOULD IT ALL COME TOGETHER IDEALLY.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
UPDATE...BAUMGARDT
SHORT TERM...04
LONG TERM....04
AVIATION...BAUMGARDT
AREA FORECAST DISCUSSION...UPDATED
NWS MILWAUKEE/SULLIVAN WI
1233 PM CDT SAT JUL 11 2015
UPDATED AVIATION SECTION
.UPDATE...
MESO MODELS CONTINUE TO JUST BRUSH SOUTHERN WI WITH PRECIP THROUGH
THE AFTERNOON. THE PRECIP IS ON THE NORTHERN EDGE OF A REMNANT MCV
THAT WILL BE ROLLING ACROSS NORTHERN WI TODAY. THERE IS STILL A
SMALL CHANCE FOR SHOWERS AND MAYBE A RUMBLE OF THUNDER ACROSS THE
WHOLE MKX FORECAST AREA THROUGH MID AFTERNOON DUE TO SOME WEAK WARM
AIR ADVECTION ALOFT. THE DRY AIR IN PLACE OVER THE AREA WILL KEEP
MOST OF THE PRECIP FROM REACHING THE GROUND. LOWERED POPS
ACCORDINGLY. THE LATEST 12Z MODELS COMING IN ARE NOW SHOWING A DRIER
FORECAST FOR TONIGHT AS WELL.
SPC REMOVED OUR FORECAST AREA FROM THE MARGINAL RISK FOR SEVERE
WEATHER NOW.
TEMPERATURES WILL BE GREATLY AFFECTED BY EXTENSIVE CLOUD SHIELD OVER
SOUTHERN WI TODAY. HIGHS WILL STRUGGLE TO REACH THE UPPER 70S NEAR
THE IL BORDER... BUT ARE ALREADY AROUND 80 TOWARD SHEBOYGAN WITH
MORE SUNSHINE.
&&
.AVIATION/18Z TAFS/...
SHOWERS WITH A POSSIBLE RUMBLE OF THUNDER WILL TRACK ACROSS FAR
SOUTH CENTRAL WI AND GRADUALLY DIMINISH AS THEY REACH SOUTHEAST WI
BY MID AFTERNOON. THESE ARE ON THE NORTHERN EDGE OF PRECIP CROSSING
NORTHERN IL. THERE IS A SMALL CHANCE FOR SHOWERS ELSEWHERE THROUGH
THE AFTERNOON DUE TO WEAK WARM AIR ADVECTION ALOFT.
THERE IS PLENTY OF DRY AIR OVER SOUTHERN WI SO SOME OF THE SHOWERS
SHOWING UP ON COMPOSITE RADAR ARE NOT REACHING THE GROUND...
APPARENT ON THE LOCAL MKX RADAR. THERE MAY BE VIRGA INSTEAD.
CHANCES FOR SHOWERS AND THUNDERSTORMS ARE NOW DIMINISHING FOR
TONIGHT AS MODELS ARE TRENDING TOWARD A DRIER FORECAST.
I HAVE LOW CONFIDENCE ABOUT CHANCES FOR IFR CIGS/VSBY TONIGHT.
SOUTHERN WI WILL BE ON THE NORTH SIDE OF THE SURFACE WARM FRONT
WHICH IS TYPICALLY A GOOD SETUP FOR LOW CLOUDS AND FOG. HOWEVER...
THE LACK OF WIDESPREAD RAIN AND HIGH DEWPOINTS MAY PRECLUDE THEIR
DEVELOPMENT.
&&
.PREV DISCUSSION... /ISSUED 326 AM CDT SAT JUL 11 2015/
TODAY AND TONIGHT...FORECAST CONFIDENCE MEDIUM.
500 MB RIDGE AXIS AND SFC HIGH PRESSURE EXITS THE REGION EARLY
SATURDAY MORNING AS A SHORTWAVE TROUGH AND LOW LEVEL WARM AIR
ADVECTION ALONG A WARM FRONT MAKES ITS WAY INTO THE REGION. MAINLY
HIGH CLOUDS IN THE AREA AHEAD OF THE SHORTWAVE. SOME -SHRA CAN BE
SEEN IN SOUTHEAST IOWA AT 08Z SATURDAY...MOVING NORTHEAST AHEAD THE
LOW LEVEL BAROCLINIC ZONE. HIGHS SATURDAY LOOK TO BE NEAR 80F ACROSS
S WI...AS 925 MB TEMPS ARE PROGGED TO BE NEAR 20C BY THE GFS. 925 MB
TEMPERATURES WILL ONLY INCREASE FROM THERE AS WARM FRONT TRANSLATES
NORTHEAST.
11.06 HRRR MESO MODEL IS SHOWING THE BULK OF THE PRECIPITATION
DURING THE DAY SATURDAY TO BE SOUTH OF THE WI/IL BORDER AS THE HRRR
IS PROGGING AN MCV DEVELOPING ACROSS N IL. THIS IS INDICATED IN THE
GFS MODEL AS WELL...KEEPING THE STRONGEST MID-LEVEL SUPPORT SOUTH AS
ISENTROPIC OMEGA VALUES REACH NEARLY 9 UBAR/S IN THE GFS.
SO...REDUCED THE POPS DURING THE DAY SATURDAY.
THE BEST CHANCES OF PRECIPITATION WILL BE SATURDAY NIGHT AS THE BEST
WARM AIR ADVECTION AND INSTABILITY AXIS REACHES S WI. KEPT LIKELY
POPS AS BETTER 850-700 MB FRONTOGENETICAL FORCING AND 850-700 MB Q-
VECTOR CONVERGENCE CREEPS INTO THE REGION DURING THIS TIME. THERE IS
A MARGINAL RISK FOR SEVERE WEATHER SOUTHWEST OF A JANESVILLE TO
CROSS PLAINS TO LOGANVILLE LINE. GOOD INSTABILITY WILL DEVELOP IN
THE EVENING AND OVERNIGHT HOURS SATURDAY INTO SUNDAY AS THE LOW
LEVEL WAA COMES IN. MOST UNSTABLE CAPE VALUES ARE PROGGED TO REACH
2500+ J/KG ACCORDING TO THE GFS...WHILE THE NAM AND ECMWF ARE
SHOWING MUCAPE ONLY AOA 1000 J/KG.
SUNDAY - CONFIDENCE...MEDIUM
GRADUAL BUILDING OF HEIGHTS WITH ONE SHORTWAVE EXITING THE
WESTERN GREAT LAKES REGION. GFS BLOWS UP ANOTHER ONE WITHIN THE
BUILDING HEIGHTS REGIME BUT THIS APPEARS TO BE ERRONEOUS WITH
OTHER MODELS SHOWING A CLEANER BUILDUP OF THE MID LEVEL RIDGE
AXIS. MODELS SHOW SOME LINGERING SHRA/PSBL TSRA PRIOR TO 18Z WITH
INFLUENCE OF THE DEPARTING WAVE AND 850/925 BAROCLINICITY. THE 850
FRONT SHIFTS FURTHER NE WITH 925 TEMPS REALLY SOARING THOUGH THE
12Z ECMWF HANGS ONTO THIS BOUNDARY LONGER WHICH SHOWS A COOLER
REGIME THAN WHAT THE NAM/GFS IMPLIES. THE GFS SOUNDINGS SHOW CAPES
BUILDING UP TO 3000 J/KG WITH INVERSION JUST UNDER 5K FEET. SOME
AREAS SEEING SIGNIFICANT CIN DEVELOPING. LIFT BECOMES LESS
DISCERNIBLE IN THE AFTERNOON NORTHWARD SHIFT OF WARM FRONT AND ANY
UPPER FORCING QUESTIONABLE GIVEN THE PROGGD ERRONEOUS VORT
BULLSEYE ON THE GFS. WILL GO WITH TEMPS WELL INTO THE 80S WITH
SOME ONSHORE COOLING EFFECTS IN THE EAST.
SUNDAY NIGHT INTO MONDAY - CONFIDENCE...MEDIUM
EXPECTING AN MCS TO RIDE ALONG LOWER LEVEL BAROCLINICITY LATER
SUNDAY NIGHT. UPPER LEVEL JET WILL BE FAVORABLY PLACED WITH LEFT
FRONT QUADRANT AND MID LEVEL WAVE RIDING INTO THE UPPER MIDWEST.
THE NAM AND GFS SHOW GREATEST WINDOW OF CONCERN BETWEEN 06-12Z.
THE 12Z ECMWF WAS SHOWING A SLOWER SOLUTION WITH 12-18Z BEING MORE
PRIME. THE LATEST ECMWF SHOWS A LITTLE QUICKER SOLUTION. AIRMASS
WILL BE RATHER UNSTABLE THROUGH THE NIGHT. PER SPC DISC FOR SWODY2
THE CONVECTION AFFECTING SRN WI WILL HAVE EVOLVED INTO MORE OF A
WIND EVENT AS THESE STORMS RIDE IN NW-SE. CONVECTIVE
REDEVELOPMENT WILL HINGE ON HOW BOUNDARIES LAY OUT AFTER THE
MORNING STORMS. MID LEVEL FLOW STILL CYCLONIC WITH 250 JET STILL
POSITIONED TO OUR SOUTHWEST WITH DIVERGENCE STILL NOTED ACROSS THE
AREA. IF AIRMASS CAN RELOAD LOOKING AT CAPE BUILDUP WITH AFTERNOON
STORMS ASSOCIATED WITH SURFACE TROUGH...BUT AGAIN LOTS WILL DEPEND
ON HOW AIRMASS SETS UP AFTER THE MORNING ACTIVITY. ATTM SPC SWODY3
IS KEYING ON THIS BEING MORE ROBUST FURTHER SOUTH OF OUR CWA
PROBABLY MORE CO-LOCATED WITH THE OUTFLOW FROM EARLIER STORMS.
TUESDAY - CONFIDENCE...LOW
ECMWF/NAM SHOW WEAK SURFACE TROUGH LINGERING WHILE THE GFS SHIFTS
BOUNDARY TO OUR SOUTH WITH NE WINDS AND HIGH PRESSURE NOSING IN.
SO NEED TO RETAIN SOME POPS FOR THE SLOWER SOLUTIONS WHICH
INCLUDES THE NAM AS WELL. ECMWF SHOWS A FAIRLY POTENT WAVE
ARRIVINGDURING PRIME TIME AS WELL. HOPEFULLY FUTURE MODEL RUNS
WILL COME INTO BETTER AGREEMENT ON THIS.
TUESDAY NIGHT AND WEDNESDAY - CONFIDENCE...MEDIUM
MODELS SHOW HIGH PRESSURE BUILDING IN WITH NE-E FLOW AND COOLER
AIRMASS.
THURSDAY AND FRIDAY - CONFIDENCE...LOW
THE 00Z ECMWF ESSENTIALLY KEEPS THE INFLUENCE OF THE HIGH IN
PLACE THIS PERIOD AS NEXT TROUGH AND ASSOCIATED PRECIP HANGS OUT
IN THE PLAINS. THE GFS IS MORE PROGRESSIVE AND SHOWS A MORE ACTIVE
PERIOD WITH POTENTIALLY SEVERAL ROUNDS OF PRECIP. GIVEN THE
DISPARITY WILL LEAN ON THE SUPERBLEND POPS FOR NOW.
AVIATION/12Z TAFS/...VFR CONDITIONS ARE EXPECTED TO CONTINUE THROUGH
SATURDAY MORNING UNTIL LOWER LEVEL CLOUDS AND PERHAPS SOME -SHRA MOVE
INTO THE REGION. A MID-LEVEL SHORTWAVE TROUGH WILL SWEEP IN TO THE
AREA ALONG WITH A PUSH OF WARMER AIR IN THE 925-850 MB LAYER. BEST
CHANCES OF PRECIPITATION WILL BE SATURDAY EVENING AND OVERNIGHT AS
BETTER FORCING ARRIVES AT THAT TIME.
&&
.MKX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
LM...NONE.
&&
$$
UPDATE...MRC
TODAY/TONIGHT AND AVIATION/MARINE...JTS
SUNDAY THROUGH FRIDAY...COLLAR
AREA FORECAST DISCUSSION...UPDATED
NWS MILWAUKEE/SULLIVAN WI
1206 PM CDT SAT JUL 11 2015
.UPDATE...
MESO MODELS CONTINUE TO JUST BRUSH SOUTHERN WI WITH PRECIP THROUGH
THE AFTERNOON. THE PRECIP IS ON THE NORTHERN EDGE OF A REMNANT MCV
THAT WILL BE ROLLING ACROSS NORTHERN WI TODAY. THERE IS STILL A
SMALL CHANCE FOR SHOWERS AND MAYBE A RUMBLE OF THUNDER ACROSS THE
WHOLE MKX FORECAST AREA THROUGH MID AFTERNOON DUE TO SOME WEAK WARM
AIR ADVECTION ALOFT. THE DRY AIR IN PLACE OVER THE AREA WILL KEEP
MOST OF THE PRECIP FROM REACHING THE GROUND. LOWERED POPS
ACCORDINGLY. THE LATEST 12Z MODELS COMING IN ARE NOW SHOWING A DRIER
FORECAST FOR TONIGHT AS WELL.
SPC REMOVED OUR FORECAST AREA FROM THE MARGINAL RISK FOR SEVERE
WEATHER NOW.
TEMPERATURES WILL BE GREATLY AFFECTED BY EXTENSIVE CLOUD SHIELD OVER
SOUTHERN WI TODAY. HIGHS WILL STRUGGLE TO REACH THE UPPER 70S NEAR
THE IL BORDER... BUT ARE ALREADY AROUND 80 TOWARD SHEBOYGAN WITH
MORE SUNSHINE.
&&
.AVIATION/18Z TAFS/...
SHOWERS WITH A POSSIBLE RUMBLE OF THUNDER WILL TRACK ACROSS FAR
SOUTH CENTRAL WI AND GRADUALLY DIMINISH AS THEY REACH SOUTHEAST WI
BY MID AFTERNOON. THESE ARE ON THE NORTHERN EDGE OF PRECIP CROSSING
NORTHERN IL. THERE IS A SMALL CHANCE FOR SHOWERS ELSEWHERE THROUGH
THE AFTERNOON DUE TO WEAK WARM AIR ADVECTION ALOFT.
THERE IS PLENTY OF DRY AIR OVER SOUTHERN WI SO SOME OF THE SHOWERS
SHOWING UP ON COMPOSITE RADAR ARE NOT REACHING THE GROUND...
APPARENT ON THE LOCAL MKX RADAR. THERE MAY BE VIRGA INSTEAD.
CHANCES FOR SHOWERS AND THUNDERSTORMS ARE NOW DIMINISHING FOR
TONIGHT AS MODELS ARE TRENDING TOWARD A DRIER FORECAST.
&&
.PREV DISCUSSION... /ISSUED 326 AM CDT SAT JUL 11 2015/
TODAY AND TONIGHT...FORECAST CONFIDENCE MEDIUM.
500 MB RIDGE AXIS AND SFC HIGH PRESSURE EXITS THE REGION EARLY
SATURDAY MORNING AS A SHORTWAVE TROUGH AND LOW LEVEL WARM AIR
ADVECTION ALONG A WARM FRONT MAKES ITS WAY INTO THE REGION. MAINLY
HIGH CLOUDS IN THE AREA AHEAD OF THE SHORTWAVE. SOME -SHRA CAN BE
SEEN IN SOUTHEAST IOWA AT 08Z SATURDAY...MOVING NORTHEAST AHEAD THE
LOW LEVEL BAROCLINIC ZONE. HIGHS SATURDAY LOOK TO BE NEAR 80F ACROSS
S WI...AS 925 MB TEMPS ARE PROGGED TO BE NEAR 20C BY THE GFS. 925 MB
TEMPERATURES WILL ONLY INCREASE FROM THERE AS WARM FRONT TRANSLATES
NORTHEAST.
11.06 HRRR MESO MODEL IS SHOWING THE BULK OF THE PRECIPITATION
DURING THE DAY SATURDAY TO BE SOUTH OF THE WI/IL BORDER AS THE HRRR
IS PROGGING AN MCV DEVELOPING ACROSS N IL. THIS IS INDICATED IN THE
GFS MODEL AS WELL...KEEPING THE STRONGEST MID-LEVEL SUPPORT SOUTH AS
ISENTROPIC OMEGA VALUES REACH NEARLY 9 UBAR/S IN THE GFS.
SO...REDUCED THE POPS DURING THE DAY SATURDAY.
THE BEST CHANCES OF PRECIPITATION WILL BE SATURDAY NIGHT AS THE BEST
WARM AIR ADVECTION AND INSTABILITY AXIS REACHES S WI. KEPT LIKELY
POPS AS BETTER 850-700 MB FRONTOGENETICAL FORCING AND 850-700 MB Q-
VECTOR CONVERGENCE CREEPS INTO THE REGION DURING THIS TIME. THERE IS
A MARGINAL RISK FOR SEVERE WEATHER SOUTHWEST OF A JANESVILLE TO
CROSS PLAINS TO LOGANVILLE LINE. GOOD INSTABILITY WILL DEVELOP IN
THE EVENING AND OVERNIGHT HOURS SATURDAY INTO SUNDAY AS THE LOW
LEVEL WAA COMES IN. MOST UNSTABLE CAPE VALUES ARE PROGGED TO REACH
2500+ J/KG ACCORDING TO THE GFS...WHILE THE NAM AND ECMWF ARE
SHOWING MUCAPE ONLY AOA 1000 J/KG.
SUNDAY - CONFIDENCE...MEDIUM
GRADUAL BUILDING OF HEIGHTS WITH ONE SHORTWAVE EXITING THE
WESTERN GREAT LAKES REGION. GFS BLOWS UP ANOTHER ONE WITHIN THE
BUILDING HEIGHTS REGIME BUT THIS APPEARS TO BE ERRONEOUS WITH
OTHER MODELS SHOWING A CLEANER BUILDUP OF THE MID LEVEL RIDGE
AXIS. MODELS SHOW SOME LINGERING SHRA/PSBL TSRA PRIOR TO 18Z WITH
INFLUENCE OF THE DEPARTING WAVE AND 850/925 BAROCLINICITY. THE 850
FRONT SHIFTS FURTHER NE WITH 925 TEMPS REALLY SOARING THOUGH THE
12Z ECMWF HANGS ONTO THIS BOUNDARY LONGER WHICH SHOWS A COOLER
REGIME THAN WHAT THE NAM/GFS IMPLIES. THE GFS SOUNDINGS SHOW CAPES
BUILDING UP TO 3000 J/KG WITH INVERSION JUST UNDER 5K FEET. SOME
AREAS SEEING SIGNIFICANT CIN DEVELOPING. LIFT BECOMES LESS
DISCERNIBLE IN THE AFTERNOON NORTHWARD SHIFT OF WARM FRONT AND ANY
UPPER FORCING QUESTIONABLE GIVEN THE PROGGD ERRONEOUS VORT
BULLSEYE ON THE GFS. WILL GO WITH TEMPS WELL INTO THE 80S WITH
SOME ONSHORE COOLING EFFECTS IN THE EAST.
SUNDAY NIGHT INTO MONDAY - CONFIDENCE...MEDIUM
EXPECTING AN MCS TO RIDE ALONG LOWER LEVEL BAROCLINICITY LATER
SUNDAY NIGHT. UPPER LEVEL JET WILL BE FAVORABLY PLACED WITH LEFT
FRONT QUADRANT AND MID LEVEL WAVE RIDING INTO THE UPPER MIDWEST.
THE NAM AND GFS SHOW GREATEST WINDOW OF CONCERN BETWEEN 06-12Z.
THE 12Z ECMWF WAS SHOWING A SLOWER SOLUTION WITH 12-18Z BEING MORE
PRIME. THE LATEST ECMWF SHOWS A LITTLE QUICKER SOLUTION. AIRMASS
WILL BE RATHER UNSTABLE THROUGH THE NIGHT. PER SPC DISC FOR SWODY2
THE CONVECTION AFFECTING SRN WI WILL HAVE EVOLVED INTO MORE OF A
WIND EVENT AS THESE STORMS RIDE IN NW-SE. CONVECTIVE
REDEVELOPMENT WILL HINGE ON HOW BOUNDARIES LAY OUT AFTER THE
MORNING STORMS. MID LEVEL FLOW STILL CYCLONIC WITH 250 JET STILL
POSITIONED TO OUR SOUTHWEST WITH DIVERGENCE STILL NOTED ACROSS THE
AREA. IF AIRMASS CAN RELOAD LOOKING AT CAPE BUILDUP WITH AFTERNOON
STORMS ASSOCIATED WITH SURFACE TROUGH...BUT AGAIN LOTS WILL DEPEND
ON HOW AIRMASS SETS UP AFTER THE MORNING ACTIVITY. ATTM SPC SWODY3
IS KEYING ON THIS BEING MORE ROBUST FURTHER SOUTH OF OUR CWA
PROBABLY MORE CO-LOCATED WITH THE OUTFLOW FROM EARLIER STORMS.
TUESDAY - CONFIDENCE...LOW
ECMWF/NAM SHOW WEAK SURFACE TROUGH LINGERING WHILE THE GFS SHIFTS
BOUNDARY TO OUR SOUTH WITH NE WINDS AND HIGH PRESSURE NOSING IN.
SO NEED TO RETAIN SOME POPS FOR THE SLOWER SOLUTIONS WHICH
INCLUDES THE NAM AS WELL. ECMWF SHOWS A FAIRLY POTENT WAVE
ARRIVINGDURING PRIME TIME AS WELL. HOPEFULLY FUTURE MODEL RUNS
WILL COME INTO BETTER AGREEMENT ON THIS.
TUESDAY NIGHT AND WEDNESDAY - CONFIDENCE...MEDIUM
MODELS SHOW HIGH PRESSURE BUILDING IN WITH NE-E FLOW AND COOLER
AIRMASS.
THURSDAY AND FRIDAY - CONFIDENCE...LOW
THE 00Z ECMWF ESSENTIALLY KEEPS THE INFLUENCE OF THE HIGH IN
PLACE THIS PERIOD AS NEXT TROUGH AND ASSOCIATED PRECIP HANGS OUT
IN THE PLAINS. THE GFS IS MORE PROGRESSIVE AND SHOWS A MORE ACTIVE
PERIOD WITH POTENTIALLY SEVERAL ROUNDS OF PRECIP. GIVEN THE
DISPARITY WILL LEAN ON THE SUPERBLEND POPS FOR NOW.
AVIATION/12Z TAFS/...VFR CONDITIONS ARE EXPECTED TO CONTINUE THROUGH
SATURDAY MORNING UNTIL LOWER LEVEL CLOUDS AND PERHAPS SOME -SHRA MOVE
INTO THE REGION. A MID-LEVEL SHORTWAVE TROUGH WILL SWEEP IN TO THE
AREA ALONG WITH A PUSH OF WARMER AIR IN THE 925-850 MB LAYER. BEST
CHANCES OF PRECIPITATION WILL BE SATURDAY EVENING AND OVERNIGHT AS
BETTER FORCING ARRIVES AT THAT TIME.
&&
.MKX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
LM...NONE.
&&
$$
UPDATE...MRC
TODAY/TONIGHT AND AVIATION/MARINE...JTS
SUNDAY THROUGH FRIDAY...COLLAR
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
1147 AM CDT SAT JUL 11 2015
.UPDATE...
ISSUED AT 1146 AM CDT SAT JUL 11 2015
HAVE BEEN WORKING THROUGH THE MORNING AT TRYING TO KEEP AHEAD OF
THE WEATHER. SHORTWAVE TROUGH ENERGY UPSTREAM MOVING AT THE AREA
IS PROVIDING ENOUGH LIFT WITH WEAK WARM ADVECTION AND MINOR MUCAPE
/250 J/KG/ OF INSTABILITY TO POP SHOWERS AND ISOLATED THUNDER.
BELIEVE THE AREA WILL CONTINUE TO MOVE EAST THROUGH THE DAY AND
FEEL SOME DIMINISHMENT MAY OCCUR AS IT DOES. BEHIND THE
WAVE...BELIEVE MANY HOURS OF DRY WEATHER WILL HOLD WITH LITTLE
FORCING UNTIL AFTER MIDNIGHT. HAVE LOWERED THE RAIN CHANCES BEHIND
THE WEATHER UNTIL LATER TONIGHT...BUT AM STILL ASSESSING LATER
INTO THE OVERNIGHT.
SUBSTANTIAL CLOUD AND RAIN HAS CAUSED TEMPERATURES TO REALLY STAY
COOL. HAVE LOWERED HIGHS TODAY SOME...BUT SOME LATE SUN COULD POP
THEM UP FAST. SO...HAVE KEPT THE AFTERNOON COOL WITH A LATE JUMP.
RAIN RATES ARE PRETTY IMPRESSIVE WITH SUCH LITTLE CAPE. THESE
LITTLE SHOWERS ON RADAR ARE CAUSING SOME GOOD DOWNPOURS. 50DBZ
CORE NEAR AUTIN MN CAUSED 0.75 INCHES OF RAIN IN A SHORT AMOUNT OF
TIME. HERE COMES THE HIGHER PRECIPITABLE WATER WITH 1.5 INCH
VALUES TRANSPORTING NORTH OVER THE AREA TODAY.
&&
.SHORT TERM...(TODAY THROUGH MONDAY)
ISSUED AT 339 AM CDT SAT JUL 11 2015
REGIONAL RADARS THIS MORNING SHOWING SOME CONVECTION THIS MORNING
OVER NORTHERN MISSOURI WITH ANOTHER AREA OF CONVECTION OVER
EASTERN NEBRASKA. THIS ACTIVITY IS NORTH OF A WARM FRONT THAT
EXTENDS ACROSS NORTHERN KANSAS AND MISSOURI AND AHEAD OF A WEAK
TROUGH OF LOW PRESSURE FROM KANSAS INTO NORTH DAKOTA. WATER VAPOR
SATELLITE SHOWS ONE SHORT WAVE TROUGH OVER NEBRASKA AND KANSAS
WITH ANOTHER OVER NORTH DAKOTA. THE TREND IN THE 11.00Z MODELS AND
11.03Z RAP IS FOR THE WAVE OVER NEBRASKA AND KANSAS TO FLATTEN
OUT AS IT MOVES NORTHEAST INTO THE TOP PART OF THE RIDGE AXIS OVER
THE CENTRAL PART OF THE COUNTRY. THE WAVE OVER NORTH DAKOTA WILL
ALSO CONTINUE TO MOVE NORTHEAST INTO SOUTHERN CANADA THROUGH THE
DAY. THE SURFACE WARM FRONT SHOULD LIFT SLOWLY TO THE NORTH WITH A
GENERAL MODEL CONSENSUS OF IT REACHING ABOUT THE IOWA/MISSOURI
BORDER. THIS WILL KEEP THE BEST MOISTURE TRANSPORT WELL SOUTH OF
THE AREA TODAY AND SHOULD KEEP MOST OF THE RAIN TO THE SOUTH AS
WELL. THE MESO MODELS SEEMED TO HAVE LATCHED ON TO THIS AS WELL
WITH THE 11.00Z CR-NAM NEST...HI-RES ARW AND NMM KEEPING THE AREA
DRY WHILE THE 11.00Z NAM12 AND 11.05Z HRRR STILL TRY TO BRING THE
REMAINS OF SOME DEVELOPING CENTRAL IOWA CONVECTION INTO THE
SOUTHERN SECTIONS FOR THIS MORNING. BASED ON ALL THESE
SOLUTIONS...HAVE TRENDED THE RAIN CHANCES DOWN FOR TODAY WITH
ABOUT A 20 PERCENT CHANCE ACROSS THE NORTH TO AT MOST A 40 PERCENT
CHANCE IN THE SOUTH. THESE COULD STILL BE TOO HIGH AS IT COULD END
UP BEING TOTALLY DRY NORTH OF THE IOWA/MINNESOTA BORDER.
UPPER LEVEL HEIGHTS SHOULD BUILD A LITTLE BIT OVER THE REGION
TONIGHT AS THE SHORT WAVE TROUGHS MOVE OFF TO THE EAST. THE WARM
FRONT WILL CONTINUE TO LIFT SLOWLY NORTH TAKING ON A MORE
NORTHWEST TO SOUTHEAST ORIENTATION FROM A DEVELOPING AREA OF LOW
PRESSURE OVER NORTH DAKOTA INTO CENTRAL ILLINOIS. THE NAM REALLY
RAMPS UP THE MOISTURE TRANSPORT INTO THIS BOUNDARY AROUND 06Z
SUNDAY AND BREAKS OUT CONVECTION NORTH OF THE BOUNDARY AND ACROSS
THE AREA. THE 11.00Z GFS SOMEWHAT HINTS AT THIS AS WELL WHILE THE
11.00Z ECMWF KEEPS THE BOUNDARY FARTHER SOUTH AND MOST OF THE RAIN
TO THE SOUTH AS WELL. THE HI-RES NMM IS SIMILAR TO THE NAM WHILE
THE HI-RES ARW IS COMPLETELY DRY FOR TONIGHT. CONCERNED THAT
THE NAM IS TOO STRONG WITH THE MOISTURE TRANSPORT TONIGHT AND WILL
ONLY CARRY A GENERAL 30 TO 40 PERCENT CHANCE ACROSS THE AREA.
THE REAL ACTION AND BEST CHANCES FOR RAIN MAY COME SUNDAY NIGHT. A
SHORT WAVE TROUGH IS EXPECTED TO COME OUT OF THE WEAKENING UPPER
LEVEL LOW CURRENTLY OVER OREGON AND NEVADA. THIS WAVE SHOULD TOP
THE UPPER LEVEL RIDGE AND THEN SLIDE SOUTHEAST ACROSS THE AREA
SUNDAY NIGHT. THE GFS SUGGESTS THIS WAVE WILL PRODUCE SOME
MODERATE PV ADVECTION IN THE 500-300 MB LAYER AS IT COMES ACROSS.
THIS LIFT SHOULD BE AIDED BY SOME JET DYNAMICS FROM THE LEFT EXIT
REGION OF THE 300 MB JET AS THIS COMES IN WITH THE SHORT WAVE
TROUGH. THE WARM FRONT SHOULD CONTINUE TO EDGE NORTH EXTENDING
FROM EASTERN NORTH DAKOTA INTO ILLINOIS WITH THE GFS SHOWING WEAK
TO MODERATE FRONTOGENESIS IN THE 1000-850 MB LAYER NORTH OF THE
FRONT. AS THE SHORT WAVE TROUGH APPROACHES...A CONVECTIVE COMPLEX
SHOULD FROM LATE SUNDAY AFTERNOON OVER THE EASTERN DAKOTAS AND
THEN SLIDE SOUTHEAST THROUGH THE NIGHT ALONG AND NORTH OF THE WARM
FRONT. THERE SHOULD STILL BE AMPLE CAPE AVAILABLE FOR THE STORMS
TO WORK WITH AS THEY MOVE INTO THE AREA. THE GFS SUGGESTS UP TO
2500 J/KG OF ML CAPE SUNDAY EVENING ONLY DROPPING OFF TO 1500 J/KG
DURING THE OVERNIGHT HOURS. UP TO 40 KNOTS OF SHEAR SHOULD MOVE IN
AHEAD OF THE SHORT WAVE TROUGH WITH THIS BEING PRIMARILY IN THE
0-3 KM LAYER. THIS WILL PRESENT THE OPPORTUNITY FOR A NOCTURNAL
MCS TO ROLL ACROSS THE AREA WITH A SEVERE WIND THREAT. HAIL DOES
NOT LOOK TO BE MUCH OF THREAT WITH WARM CLOUD DEPTHS ON THE ORDER
OF 3.5 TO 4 KM...BUT THERE SHOULD BE SOME GOOD RAINFALL RATES AND
LOCALLY HEAVY RAINS.
.LONG TERM...(MONDAY NIGHT THROUGH FRIDAY)
ISSUED AT 339 AM CDT SAT JUL 11 2015
THE UPPER LEVEL RIDGE SHOULD BRIEFLY BUILD BACK OVER THE REGION
EARLY IN THE WEEK BEFORE FLATTENING OUT WITH ZONAL FLOW OVER THE
UPPER MIDWEST. THIS PATTERN LOOKS TO BE A DIRTY FLOW WITH THE
POTENTIAL FOR SEVERAL SHORT WAVE TROUGHS TO BE EMBEDDED IN THE
FLOW AND COME ACROSS THE REGION. DECENT AGREEMENT IN TIMING OF A
WAVE FOR WEDNESDAY BETWEEN THE ECMWF AND GFS...BUT DIFFERENCES IN
STRENGTH WITH THE GFS BEING STRONGER. AFTER THAT...CONSIDERABLE
DIFFERENCES IN HOW AN UPPER LEVEL LOW COMING ACROSS SOUTHWEST
CANADA IS HANDLED. THE GFS OPENS THIS SYSTEM UP AND BRINGS IT
TOWARD THE AREA BY THE END OF THE WEEK WHILE THE ECMWF KEEPS IT AS
A CLOSED LOW HOLDING IT BACK WITH RIDGING OVER THE REGION. WITH
ALL THE UNCERTAINTY...WILL STAY WITH GENERAL 20 TO 40 PERCENT
CHANCES THROUGH THE PERIOD.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SUNDAY MORNING)
ISSUED AT 622 AM CDT SAT JUL 11 2015
A GENERALLY VFR PERIOD EXPECTED TODAY/TONIGHT. INCREASING MOISTURE
DOES LOOK TO SPREAD 3500-4500 FT BKN CIGS ACROSS THE AREA LATE THIS
MORNING INTO EARLY THIS EVENING...WITH THESE CLOUDS/MOISTURE
SPREADING NORTHWARD ACROSS IA EARLY THIS MORNING. SOME DRYING OF THE
LOWER PORTION OF THE COLUMN TONIGHT...WITH MORE SCT CUMULUS/STRATO-
CUMULUS EXPECTED AFTER 01-02Z. SHRA/TSRA CHANCES AT THE TAF SITES
MORE IN QUESTION THIS AFTERNOON THRU TONIGHT. GIVEN EXPECTED WIDELY
SCT TO SCT COVERAGE OF ANY SHRA/TSRA THIS AFTERNOON/TONIGHT...AND
LOWER CONFIDENCE IN THE TIMING OF ANY PERIODS WHEN SHRA/TSRA WOULD
BE MORE LIKELY TO OCCUR...CONTINUED THE TREND OF LEAVING VCSH/VCTS
OUT OF THE TAFS FOR NOW. IF DETAILS BECOME CLEARER ON SHRA/TSRA
OCCURRENCE NEAR/AT KLSE/KRST LATER CYCLES MAY BE ABLE TO MENTION OF
SUCH TO THE TAFS AS NEEDED.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
UPDATE...BAUMGARDT
SHORT TERM...04
LONG TERM....04
AVIATION.....RRS
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
622 AM CDT SAT JUL 11 2015
.SHORT TERM...(TODAY THROUGH MONDAY)
ISSUED AT 339 AM CDT SAT JUL 11 2015
REGIONAL RADARS THIS MORNING SHOWING SOME CONVECTION THIS MORNING
OVER NORTHERN MISSOURI WITH ANOTHER AREA OF CONVECTION OVER
EASTERN NEBRASKA. THIS ACTIVITY IS NORTH OF A WARM FRONT THAT
EXTENDS ACROSS NORTHERN KANSAS AND MISSOURI AND AHEAD OF A WEAK
TROUGH OF LOW PRESSURE FROM KANSAS INTO NORTH DAKOTA. WATER VAPOR
SATELLITE SHOWS ONE SHORT WAVE TROUGH OVER NEBRASKA AND KANSAS
WITH ANOTHER OVER NORTH DAKOTA. THE TREND IN THE 11.00Z MODELS AND
11.03Z RAP IS FOR THE WAVE OVER NEBRASKA AND KANSAS TO FLATTEN
OUT AS IT MOVES NORTHEAST INTO THE TOP PART OF THE RIDGE AXIS OVER
THE CENTRAL PART OF THE COUNTRY. THE WAVE OVER NORTH DAKOTA WILL
ALSO CONTINUE TO MOVE NORTHEAST INTO SOUTHERN CANADA THROUGH THE
DAY. THE SURFACE WARM FRONT SHOULD LIFT SLOWLY TO THE NORTH WITH A
GENERAL MODEL CONSENSUS OF IT REACHING ABOUT THE IOWA/MISSOURI
BORDER. THIS WILL KEEP THE BEST MOISTURE TRANSPORT WELL SOUTH OF
THE AREA TODAY AND SHOULD KEEP MOST OF THE RAIN TO THE SOUTH AS
WELL. THE MESO MODELS SEEMED TO HAVE LATCHED ON TO THIS AS WELL
WITH THE 11.00Z CR-NAM NEST...HI-RES ARW AND NMM KEEPING THE AREA
DRY WHILE THE 11.00Z NAM12 AND 11.05Z HRRR STILL TRY TO BRING THE
REMAINS OF SOME DEVELOPING CENTRAL IOWA CONVECTION INTO THE
SOUTHERN SECTIONS FOR THIS MORNING. BASED ON ALL THESE
SOLUTIONS...HAVE TRENDED THE RAIN CHANCES DOWN FOR TODAY WITH
ABOUT A 20 PERCENT CHANCE ACROSS THE NORTH TO AT MOST A 40 PERCENT
CHANCE IN THE SOUTH. THESE COULD STILL BE TOO HIGH AS IT COULD END
UP BEING TOTALLY DRY NORTH OF THE IOWA/MINNESOTA BORDER.
UPPER LEVEL HEIGHTS SHOULD BUILD A LITTLE BIT OVER THE REGION
TONIGHT AS THE SHORT WAVE TROUGHS MOVE OFF TO THE EAST. THE WARM
FRONT WILL CONTINUE TO LIFT SLOWLY NORTH TAKING ON A MORE
NORTHWEST TO SOUTHEAST ORIENTATION FROM A DEVELOPING AREA OF LOW
PRESSURE OVER NORTH DAKOTA INTO CENTRAL ILLINOIS. THE NAM REALLY
RAMPS UP THE MOISTURE TRANSPORT INTO THIS BOUNDARY AROUND 06Z
SUNDAY AND BREAKS OUT CONVECTION NORTH OF THE BOUNDARY AND ACROSS
THE AREA. THE 11.00Z GFS SOMEWHAT HINTS AT THIS AS WELL WHILE THE
11.00Z ECMWF KEEPS THE BOUNDARY FARTHER SOUTH AND MOST OF THE RAIN
TO THE SOUTH AS WELL. THE HI-RES NMM IS SIMILAR TO THE NAM WHILE
THE HI-RES ARW IS COMPLETELY DRY FOR TONIGHT. CONCERNED THAT
THE NAM IS TOO STRONG WITH THE MOISTURE TRANSPORT TONIGHT AND WILL
ONLY CARRY A GENERAL 30 TO 40 PERCENT CHANCE ACROSS THE AREA.
THE REAL ACTION AND BEST CHANCES FOR RAIN MAY COME SUNDAY NIGHT. A
SHORT WAVE TROUGH IS EXPECTED TO COME OUT OF THE WEAKENING UPPER
LEVEL LOW CURRENTLY OVER OREGON AND NEVADA. THIS WAVE SHOULD TOP
THE UPPER LEVEL RIDGE AND THEN SLIDE SOUTHEAST ACROSS THE AREA
SUNDAY NIGHT. THE GFS SUGGESTS THIS WAVE WILL PRODUCE SOME
MODERATE PV ADVECTION IN THE 500-300 MB LAYER AS IT COMES ACROSS.
THIS LIFT SHOULD BE AIDED BY SOME JET DYNAMICS FROM THE LEFT EXIT
REGION OF THE 300 MB JET AS THIS COMES IN WITH THE SHORT WAVE
TROUGH. THE WARM FRONT SHOULD CONTINUE TO EDGE NORTH EXTENDING
FROM EASTERN NORTH DAKOTA INTO ILLINOIS WITH THE GFS SHOWING WEAK
TO MODERATE FRONTOGENESIS IN THE 1000-850 MB LAYER NORTH OF THE
FRONT. AS THE SHORT WAVE TROUGH APPROACHES...A CONVECTIVE COMPLEX
SHOULD FROM LATE SUNDAY AFTERNOON OVER THE EASTERN DAKOTAS AND
THEN SLIDE SOUTHEAST THROUGH THE NIGHT ALONG AND NORTH OF THE WARM
FRONT. THERE SHOULD STILL BE AMPLE CAPE AVAILABLE FOR THE STORMS
TO WORK WITH AS THEY MOVE INTO THE AREA. THE GFS SUGGESTS UP TO
2500 J/KG OF ML CAPE SUNDAY EVENING ONLY DROPPING OFF TO 1500 J/KG
DURING THE OVERNIGHT HOURS. UP TO 40 KNOTS OF SHEAR SHOULD MOVE IN
AHEAD OF THE SHORT WAVE TROUGH WITH THIS BEING PRIMARILY IN THE
0-3 KM LAYER. THIS WILL PRESENT THE OPPORTUNITY FOR A NOCTURNAL
MCS TO ROLL ACROSS THE AREA WITH A SEVERE WIND THREAT. HAIL DOES
NOT LOOK TO BE MUCH OF THREAT WITH WARM CLOUD DEPTHS ON THE ORDER
OF 3.5 TO 4 KM...BUT THERE SHOULD BE SOME GOOD RAINFALL RATES AND
LOCALLY HEAVY RAINS.
.LONG TERM...(MONDAY NIGHT THROUGH FRIDAY)
ISSUED AT 339 AM CDT SAT JUL 11 2015
THE UPPER LEVEL RIDGE SHOULD BRIEFLY BUILD BACK OVER THE REGION
EARLY IN THE WEEK BEFORE FLATTENING OUT WITH ZONAL FLOW OVER THE
UPPER MIDWEST. THIS PATTERN LOOKS TO BE A DIRTY FLOW WITH THE
POTENTIAL FOR SEVERAL SHORT WAVE TROUGHS TO BE EMBEDDED IN THE
FLOW AND COME ACROSS THE REGION. DECENT AGREEMENT IN TIMING OF A
WAVE FOR WEDNESDAY BETWEEN THE ECMWF AND GFS...BUT DIFFERENCES IN
STRENGTH WITH THE GFS BEING STRONGER. AFTER THAT...CONSIDERABLE
DIFFERENCES IN HOW AN UPPER LEVEL LOW COMING ACROSS SOUTHWEST
CANADA IS HANDLED. THE GFS OPENS THIS SYSTEM UP AND BRINGS IT
TOWARD THE AREA BY THE END OF THE WEEK WHILE THE ECMWF KEEPS IT AS
A CLOSED LOW HOLDING IT BACK WITH RIDGING OVER THE REGION. WITH
ALL THE UNCERTAINTY...WILL STAY WITH GENERAL 20 TO 40 PERCENT
CHANCES THROUGH THE PERIOD.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SUNDAY MORNING)
ISSUED AT 622 AM CDT SAT JUL 11 2015
A GENERALLY VFR PERIOD EXPECTED TODAY/TONIGHT. INCREASING MOISTURE
DOES LOOK TO SPREAD 3500-4500 FT BKN CIGS ACROSS THE AREA LATE THIS
MORNING INTO EARLY THIS EVENING...WITH THESE CLOUDS/MOISTURE
SPREADING NORTHWARD ACROSS IA EARLY THIS MORNING. SOME DRYING OF THE
LOWER PORTION OF THE COLUMN TONIGHT...WITH MORE SCT CUMULUS/STRATO-
CUMULUS EXPECTED AFTER 01-02Z. SHRA/TSRA CHANCES AT THE TAF SITES
MORE IN QUESTION THIS AFTERNOON THRU TONIGHT. GIVEN EXPECTED WIDELY
SCT TO SCT COVERAGE OF ANY SHRA/TSRA THIS AFTERNOON/TONIGHT...AND
LOWER CONFIDENCE IN THE TIMING OF ANY PERIODS WHEN SHRA/TSRA WOULD
BE MORE LIKELY TO OCCUR...CONTINUED THE TREND OF LEAVING VCSH/VCTS
OUT OF THE TAFS FOR NOW. IF DETAILS BECOME CLEARER ON SHRA/TSRA
OCCURRENCE NEAR/AT KLSE/KRST LATER CYCLES MAY BE ABLE TO MENTION OF
SUCH TO THE TAFS AS NEEDED.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...04
LONG TERM....04
AVIATION.....RRS
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
340 AM CDT SAT JUL 11 2015
.SHORT TERM...(TODAY THROUGH MONDAY)
ISSUED AT 339 AM CDT SAT JUL 11 2015
REGIONAL RADARS THIS MORNING SHOWING SOME CONVECTION THIS MORNING
OVER NORTHERN MISSOURI WITH ANOTHER AREA OF CONVECTION OVER
EASTERN NEBRASKA. THIS ACTIVITY IS NORTH OF A WARM FRONT THAT
EXTENDS ACROSS NORTHERN KANSAS AND MISSOURI AND AHEAD OF A WEAK
TROUGH OF LOW PRESSURE FROM KANSAS INTO NORTH DAKOTA. WATER VAPOR
SATELLITE SHOWS ONE SHORT WAVE TROUGH OVER NEBRASKA AND KANSAS
WITH ANOTHER OVER NORTH DAKOTA. THE TREND IN THE 11.00Z MODELS AND
11.03Z RAP IS FOR THE WAVE OVER NEBRASKA AND KANSAS TO FLATTEN
OUT AS IT MOVES NORTHEAST INTO THE TOP PART OF THE RIDGE AXIS OVER
THE CENTRAL PART OF THE COUNTRY. THE WAVE OVER NORTH DAKOTA WILL
ALSO CONTINUE TO MOVE NORTHEAST INTO SOUTHERN CANADA THROUGH THE
DAY. THE SURFACE WARM FRONT SHOULD LIFT SLOWLY TO THE NORTH WITH A
GENERAL MODEL CONSENSUS OF IT REACHING ABOUT THE IOWA/MISSOURI
BORDER. THIS WILL KEEP THE BEST MOISTURE TRANSPORT WELL SOUTH OF
THE AREA TODAY AND SHOULD KEEP MOST OF THE RAIN TO THE SOUTH AS
WELL. THE MESO MODELS SEEMED TO HAVE LATCHED ON TO THIS AS WELL
WITH THE 11.00Z CR-NAM NEST...HI-RES ARW AND NMM KEEPING THE AREA
DRY WHILE THE 11.00Z NAM12 AND 11.05Z HRRR STILL TRY TO BRING THE
REMAINS OF SOME DEVELOPING CENTRAL IOWA CONVECTION INTO THE
SOUTHERN SECTIONS FOR THIS MORNING. BASED ON ALL THESE
SOLUTIONS...HAVE TRENDED THE RAIN CHANCES DOWN FOR TODAY WITH
ABOUT A 20 PERCENT CHANCE ACROSS THE NORTH TO AT MOST A 40 PERCENT
CHANCE IN THE SOUTH. THESE COULD STILL BE TOO HIGH AS IT COULD END
UP BEING TOTALLY DRY NORTH OF THE IOWA/MINNESOTA BORDER.
UPPER LEVEL HEIGHTS SHOULD BUILD A LITTLE BIT OVER THE REGION
TONIGHT AS THE SHORT WAVE TROUGHS MOVE OFF TO THE EAST. THE WARM
FRONT WILL CONTINUE TO LIFT SLOWLY NORTH TAKING ON A MORE
NORTHWEST TO SOUTHEAST ORIENTATION FROM A DEVELOPING AREA OF LOW
PRESSURE OVER NORTH DAKOTA INTO CENTRAL ILLINOIS. THE NAM REALLY
RAMPS UP THE MOISTURE TRANSPORT INTO THIS BOUNDARY AROUND 06Z
SUNDAY AND BREAKS OUT CONVECTION NORTH OF THE BOUNDARY AND ACROSS
THE AREA. THE 11.00Z GFS SOMEWHAT HINTS AT THIS AS WELL WHILE THE
11.00Z ECMWF KEEPS THE BOUNDARY FARTHER SOUTH AND MOST OF THE RAIN
TO THE SOUTH AS WELL. THE HI-RES NMM IS SIMILAR TO THE NAM WHILE
THE HI-RES ARW IS COMPLETELY DRY FOR TONIGHT. CONCERNED THAT
THE NAM IS TOO STRONG WITH THE MOISTURE TRANSPORT TONIGHT AND WILL
ONLY CARRY A GENERAL 30 TO 40 PERCENT CHANCE ACROSS THE AREA.
THE REAL ACTION AND BEST CHANCES FOR RAIN MAY COME SUNDAY NIGHT. A
SHORT WAVE TROUGH IS EXPECTED TO COME OUT OF THE WEAKENING UPPER
LEVEL LOW CURRENTLY OVER OREGON AND NEVADA. THIS WAVE SHOULD TOP
THE UPPER LEVEL RIDGE AND THEN SLIDE SOUTHEAST ACROSS THE AREA
SUNDAY NIGHT. THE GFS SUGGESTS THIS WAVE WILL PRODUCE SOME
MODERATE PV ADVECTION IN THE 500-300 MB LAYER AS IT COMES ACROSS.
THIS LIFT SHOULD BE AIDED BY SOME JET DYNAMICS FROM THE LEFT EXIT
REGION OF THE 300 MB JET AS THIS COMES IN WITH THE SHORT WAVE
TROUGH. THE WARM FRONT SHOULD CONTINUE TO EDGE NORTH EXTENDING
FROM EASTERN NORTH DAKOTA INTO ILLINOIS WITH THE GFS SHOWING WEAK
TO MODERATE FRONTOGENESIS IN THE 1000-850 MB LAYER NORTH OF THE
FRONT. AS THE SHORT WAVE TROUGH APPROACHES...A CONVECTIVE COMPLEX
SHOULD FROM LATE SUNDAY AFTERNOON OVER THE EASTERN DAKOTAS AND
THEN SLIDE SOUTHEAST THROUGH THE NIGHT ALONG AND NORTH OF THE WARM
FRONT. THERE SHOULD STILL BE AMPLE CAPE AVAILABLE FOR THE STORMS
TO WORK WITH AS THEY MOVE INTO THE AREA. THE GFS SUGGESTS UP TO
2500 J/KG OF ML CAPE SUNDAY EVENING ONLY DROPPING OFF TO 1500 J/KG
DURING THE OVERNIGHT HOURS. UP TO 40 KNOTS OF SHEAR SHOULD MOVE IN
AHEAD OF THE SHORT WAVE TROUGH WITH THIS BEING PRIMARILY IN THE
0-3 KM LAYER. THIS WILL PRESENT THE OPPORTUNITY FOR A NOCTURNAL
MCS TO ROLL ACROSS THE AREA WITH A SEVERE WIND THREAT. HAIL DOES
NOT LOOK TO BE MUCH OF THREAT WITH WARM CLOUD DEPTHS ON THE ORDER
OF 3.5 TO 4 KM...BUT THERE SHOULD BE SOME GOOD RAINFALL RATES AND
LOCALLY HEAVY RAINS.
.LONG TERM...(MONDAY NIGHT THROUGH FRIDAY)
ISSUED AT 339 AM CDT SAT JUL 11 2015
THE UPPER LEVEL RIDGE SHOULD BRIEFLY BUILD BACK OVER THE REGION
EARLY IN THE WEEK BEFORE FLATTENING OUT WITH ZONAL FLOW OVER THE
UPPER MIDWEST. THIS PATTERN LOOKS TO BE A DIRTY FLOW WITH THE
POTENTIAL FOR SEVERAL SHORT WAVE TROUGHS TO BE EMBEDDED IN THE
FLOW AND COME ACROSS THE REGION. DECENT AGREEMENT IN TIMING OF A
WAVE FOR WEDNESDAY BETWEEN THE ECMWF AND GFS...BUT DIFFERENCES IN
STRENGTH WITH THE GFS BEING STRONGER. AFTER THAT...CONSIDERABLE
DIFFERENCES IN HOW AN UPPER LEVEL LOW COMING ACROSS SOUTHWEST
CANADA IS HANDLED. THE GFS OPENS THIS SYSTEM UP AND BRINGS IT
TOWARD THE AREA BY THE END OF THE WEEK WHILE THE ECMWF KEEPS IT AS
A CLOSED LOW HOLDING IT BACK WITH RIDGING OVER THE REGION. WITH
ALL THE UNCERTAINTY...WILL STAY WITH GENERAL 20 TO 40 PERCENT
CHANCES THROUGH THE PERIOD.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT)
ISSUED AT 1145 PM CDT FRI JUL 10 2015
MAJORITY OF CONVECTION THROUGH THE PERIOD EXPECTED TO REMAIN SOUTH
OF TAF AIRFIELDS WITH ONLY A 20 TO 40 PERCENT CHANCE FOR
THUNDERSTORMS. WILL KEEP 11.06Z TAFS DRY FOR NOW GIVEN COVERAGE/
TIMING UNCERTAINTY. ASSUMING RUNWAYS REMAIN DRY...ANY CEILINGS
THAT DO DEVELOP SHOULD BE ABOVE 3000 FT AGL...ALTHOUGH WILL NEED
TO WATCH NORTHWARD EXTENT OF POTENTIAL MVFR DECK ASSOCIATED WITH
PRECIPITATION THAT DEVELOPS FARTHER SOUTH. LIGHT SOUTH-SOUTHEAST
WIND WILL PERSIST AT KRST/KLSE THROUGH THE PERIOD.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...04
LONG TERM...04
AVIATION...ROGERS
AREA FORECAST DISCUSSION
NWS MILWAUKEE/SULLIVAN WI
326 AM CDT SAT JUL 11 2015
.TODAY AND TONIGHT...FORECAST CONFIDENCE MEDIUM.
500 MB RIDGE AXIS AND SFC HIGH PRESSURE EXITS THE REGION EARLY
SATURDAY MORNING AS A SHORTWAVE TROUGH AND LOW LEVEL WARM AIR
ADVECTION ALONG A WARM FRONT MAKES ITS WAY INTO THE REGION. MAINLY
HIGH CLOUDS IN THE AREA AHEAD OF THE SHORTWAVE. SOME -SHRA CAN BE
SEEN IN SOUTHEAST IOWA AT 08Z SATURDAY...MOVING NORTHEAST AHEAD THE
LOW LEVEL BAROCLINIC ZONE. HIGHS SATURDAY LOOK TO BE NEAR 80F ACROSS
S WI...AS 925 MB TEMPS ARE PROGGED TO BE NEAR 20C BY THE GFS. 925 MB
TEMPERATURES WILL ONLY INCREASE FROM THERE AS WARM FRONT TRANSLATES
NORTHEAST.
11.06 HRRR MESO MODEL IS SHOWING THE BULK OF THE PRECIPITATION
DURING THE DAY SATURDAY TO BE SOUTH OF THE WI/IL BORDER AS THE HRRR
IS PROGGING AN MCV DEVELOPING ACROSS N IL. THIS IS INDICATED IN THE
GFS MODEL AS WELL...KEEPING THE STRONGEST MID-LEVEL SUPPORT SOUTH AS
ISENTROPIC OMEGA VALUES REACH NEARLY 9 UBAR/S IN THE GFS.
SO...REDUCED THE POPS DURING THE DAY SATURDAY.
THE BEST CHANCES OF PRECIPITATION WILL BE SATURDAY NIGHT AS THE BEST
WARM AIR ADVECTION AND INSTABILITY AXIS REACHES S WI. KEPT LIKELY
POPS AS BETTER 850-700 MB FRONTOGENETICAL FORCING AND 850-700 MB Q-
VECTOR CONVERGENCE CREEPS INTO THE REGION DURING THIS TIME. THERE IS
A MARGINAL RISK FOR SEVERE WEATHER SOUTHWEST OF A JANESVILLE TO
CROSS PLAINS TO LOGANVILLE LINE. GOOD INSTABILITY WILL DEVELOP IN
THE EVENING AND OVERNIGHT HOURS SATURDAY INTO SUNDAY AS THE LOW
LEVEL WAA COMES IN. MOST UNSTABLE CAPE VALUES ARE PROGGED TO REACH
2500+ J/KG ACCORDING TO THE GFS...WHILE THE NAM AND ECMWF ARE
SHOWING MUCAPE ONLY AOA 1000 J/KG.
.SUNDAY - CONFIDENCE...MEDIUM
GRADUAL BUILDING OF HEIGHTS WITH ONE SHORTWAVE EXITING THE
WESTERN GREAT LAKES REGION. GFS BLOWS UP ANOTHER ONE WITHIN THE
BUILDING HEIGHTS REGIME BUT THIS APPEARS TO BE ERRONEOUS WITH
OTHER MODELS SHOWING A CLEANER BUILDUP OF THE MID LEVEL RIDGE
AXIS. MODELS SHOW SOME LINGERING SHRA/PSBL TSRA PRIOR TO 18Z WITH
INFLUENCE OF THE DEPARTING WAVE AND 850/925 BAROCLINICITY. THE 850
FRONT SHIFTS FURTHER NE WITH 925 TEMPS REALLY SOARING THOUGH THE
12Z ECMWF HANGS ONTO THIS BOUNDARY LONGER WHICH SHOWS A COOLER
REGIME THAN WHAT THE NAM/GFS IMPLIES. THE GFS SOUNDINGS SHOW CAPES
BUILDING UP TO 3000 J/KG WITH INVERSION JUST UNDER 5K FEET. SOME
AREAS SEEING SIGNIFICANT CIN DEVELOPING. LIFT BECOMES LESS
DISCERNIBLE IN THE AFTERNOON NORTHWARD SHIFT OF WARM FRONT AND ANY
UPPER FORCING QUESTIONABLE GIVEN THE PROGGD ERRONEOUS VORT
BULLSEYE ON THE GFS. WILL GO WITH TEMPS WELL INTO THE 80S WITH
SOME ONSHORE COOLING EFFECTS IN THE EAST.
.SUNDAY NIGHT INTO MONDAY - CONFIDENCE...MEDIUM
EXPECTING AN MCS TO RIDE ALONG LOWER LEVEL BAROCLINICITY LATER
SUNDAY NIGHT. UPPER LEVEL JET WILL BE FAVORABLY PLACED WITH LEFT
FRONT QUADRANT AND MID LEVEL WAVE RIDING INTO THE UPPER MIDWEST.
THE NAM AND GFS SHOW GREATEST WINDOW OF CONCERN BETWEEN 06-12Z.
THE 12Z ECMWF WAS SHOWING A SLOWER SOLUTION WITH 12-18Z BEING MORE
PRIME. THE LATEST ECMWF SHOWS A LITTLE QUICKER SOLUTION. AIRMASS
WILL BE RATHER UNSTABLE THROUGH THE NIGHT. PER SPC DISC FOR SWODY2
THE CONVECTION AFFECTING SRN WI WILL HAVE EVOLVED INTO MORE OF A
WIND EVENT AS THESE STORMS RIDE IN NW-SE. CONVECTIVE
REDEVELOPMENT WILL HINGE ON HOW BOUNDARIES LAY OUT AFTER THE
MORNING STORMS. MID LEVEL FLOW STILL CYCLONIC WITH 250 JET STILL
POSITIONED TO OUR SOUTHWEST WITH DIVERGENCE STILL NOTED ACROSS THE
AREA. IF AIRMASS CAN RELOAD LOOKING AT CAPE BUILDUP WITH AFTERNOON
STORMS ASSOCIATED WITH SURFACE TROUGH...BUT AGAIN LOTS WILL DEPEND
ON HOW AIRMASS SETS UP AFTER THE MORNING ACTIVITY. ATTM SPC SWODY3
IS KEYING ON THIS BEING MORE ROBUST FURTHER SOUTH OF OUR CWA
PROBABLY MORE CO-LOCATED WITH THE OUTFLOW FROM EARLIER STORMS.
.TUESDAY - CONFIDENCE...LOW
ECMWF/NAM SHOW WEAK SURFACE TROUGH LINGERING WHILE THE GFS SHIFTS
BOUNDARY TO OUR SOUTH WITH NE WINDS AND HIGH PRESSURE NOSING IN.
SO NEED TO RETAIN SOME POPS FOR THE SLOWER SOLUTIONS WHICH
INCLUDES THE NAM AS WELL. ECMWF SHOWS A FAIRLY POTENT WAVE
ARRIVINGDURING PRIME TIME AS WELL. HOPEFULLY FUTURE MODEL RUNS
WILL COME INTO BETTER AGREEMENT ON THIS.
.TUESDAY NIGHT AND WEDNESDAY - CONFIDENCE...MEDIUM
MODELS SHOW HIGH PRESSURE BUILDING IN WITH NE-E FLOW AND COOLER
AIRMASS.
.THURSDAY AND FRIDAY - CONFIDENCE...LOW
THE 00Z ECMWF ESSENTIALLY KEEPS THE INFLUENCE OF THE HIGH IN
PLACE THIS PERIOD AS NEXT TROUGH AND ASSOCIATED PRECIP HANGS OUT
IN THE PLAINS. THE GFS IS MORE PROGRESSIVE AND SHOWS A MORE ACTIVE
PERIOD WITH POTENTIALLY SEVERAL ROUNDS OF PRECIP. GIVEN THE
DISPARITY WILL LEAN ON THE SUPERBLEND POPS FOR NOW.
&&
.AVIATION/12Z TAFS/...VFR CONDITIONS ARE EXPECTED TO CONTINUE THROUGH
SATURDAY MORNING UNTIL LOWER LEVEL CLOUDS AND PERHAPS SOME -SHRA MOVE
INTO THE REGION. A MID-LEVEL SHORTWAVE TROUGH WILL SWEEP IN TO THE
AREA ALONG WITH A PUSH OF WARMER AIR IN THE 925-850 MB LAYER. BEST
CHANCES OF PRECIPITATION WILL BE SATURDAY EVENING AND OVERNIGHT AS
BETTER FORCING ARRIVES AT THAT TIME.
&&
.MKX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
LM...NONE.
&&
$$
TODAY/TONIGHT AND AVIATION...JTS
SUNDAY THROUGH FRIDAY...COLLAR
AREA FORECAST DISCUSSION
NWS CHEYENNE WY
925 PM MDT SUN JUL 12 2015
.UPDATE...
ISSUED AT 921 PM MDT SUN JUL 12 2015
REGIONAL RADARS INDICATED THAT THE ISOLATED CONVECTION OVER THE
NORTHEAST CWA DISSIPATED SHORTLY AFTER SUNSET...WITH SKIES BECOMING
MOSTLY CLEAR. LIKEWISE...WIND SPEEDS DIMINISHED AND WILL REMAIN
BETWEEN 10 AND 15 MPH TONIGHT. UPDATED EVENING ZONES HAVE BEEN
DISSEMINATED.
&&
.SHORT TERM...(THIS AFTERNOON THROUGH TUESDAY NIGHT)
ISSUED AT 258 PM MDT SUN JUL 12 2015
LOW-LEVEL CUMULUS CONTINUES TO EXPAND IN BOTH COVERAGE AND VERTICAL
EXTENT THIS AFTERNOON AS CONVECTIVE TEMPERATURES ARE REACHED. RECENT
TRENDS IN RADAR AND VISIBLE SATELLITE IMAGERY HAVE SHOWN DIFFICULTY
FOR CONVECTION TO INITIATE. THIS IS PARTIALLY DUE TO STRONG CAPPING
WITH H7 TEMPS AROUND +14 TO +16 DEG C AND LOW-LEVEL DRYING OWING TO
STRONG MIXING. THE MODELS DO NOT SHOW ANY QPF...AND THE HRRR OFFERS
LITTLE SUPPORT FOR THUNDERSTORMS TODAY. HOWEVER...OPTED TO MAINTAIN
SLIGHT CHANCE POPS THROUGH 00Z GIVEN THE RIGHT REAR QUADRANT OF A
110 KT H25 JET STREAK AND A MID-LEVEL VORT MAX OVERHEAD. SHORTWAVE
RIDGING AND RESULTANT SUBSIDENCE WILL KEEP THINGS DRY FROM TONIGHT
THROUGH MUCH OF THE DAY ON MON.
A WEAK FROPA IS STILL EXPECTED TO OCCUR ACROSS THE FAR NORTH EARLY
IN THE DAY ON MON...BUT THIS WILL HAVE LITTLE IMPACT ON OUR SENSIBLE
WEATHER AS WARM ADVECTION OCCURS BENEATH RIDGING ALOFT. THINK THIS
WILL KEEP CONVECTION SUPPRESSED OUTSIDE OF THE MOUNTAINS UNTIL AROUND
21-00Z. INCREASING MONSOONAL MOISTURE IN THE H7-H3 LAYER AND SEVERAL
DISTURBANCES EMBEDDED WITHIN SOUTHWEST FLOW ALOFT WILL ALLOW SHOWERS
AND THUNDERSTORMS TO DEVELOP EASTWARD ONTO THE PLAINS BY LATE AFTN
OR EARLY EVE. NAM/GFS BUFKIT SOUNDINGS SHOW BIG TIME DIFFERENCES IN
THE INSTABILITY PARAMETERS. THE NAM SHOWS 1500-2000 J/KG OF SBCAPE
OVER CYS ON MON AFTN...WHILE THE GFS SHOWS 200 J/KG AT MOST. 0 TO 6
KM SHEAR IS NOT IMPRESSIVE FROM EITHER MODEL...SO DO NOT EXPECT TO
SEE ANYTHING SEVERE. ANY STORMS THAT DEVELOP WILL HAVE THE POTENTIAL
FOR GUSTY WINDS GIVEN INVERTED-V PROFILES.
MOIST SOUTHWEST FLOW BECOMES BETTER ESTABLISHED ON TUE. THE INCREASE
IN MONSOONAL MOISTURE AND LARGE SCALE FORCING SHOULD PROMOTE FAIRLY
WIDESPREAD SHOWERS AND THUNDERSTORMS ACROSS THE CWA. MAINTAINED AT
LEAST SCATTERED POPS FOR MOST AREAS...HIGHEST IN THE MOUNTAINS. WEAK
FLOW ALOFT SUGGESTS LITTLE CONCERN FOR STRONGER CONVECTION DESPITE
MODERATE INSTABILITY WITH CAPES EXCEEDING 1000 J/KG. THE MODELS SHOW
THE COOLEST TEMPERATURES ALOFT ON TUE...BUT NOT MUCH DIFFERENT THAN
PREVIOUS DAYS. CONTINUED TO TREND COOLER FOR HIGHS GIVEN THAT SHOWER
ACTIVITY AND MID LEVEL CLOUD COVER SHOULD BE MORE WIDESPREAD.
.LONG TERM...(WEDNESDAY THROUGH SUNDAY)
ISSUED AT 258 PM MDT SUN JUL 12 2015
MODELS TRENDING WARMER INTO THE EXTENDED FORECAST PERIOD AS
WESTERLY FLOW ALOFT DEVELOPS OVER SOUTHEAST WYOMING AND
PANHANDLE. TEMPERATURES WILL RISE INTO THE 80S OVER MUCH OF
SOUTHEAST WYOMING FROM MID WEEK INTO THE EARLY WEEKEND WITH SOME
90S INTO THE PLAINS. 90 DEGREE HIGHS LIKELY FOR THE NEBRASKA
PANHANDLE AND WOULD NOT BE SURPRISED TO SEE A SOME 100 DEGREE
READINGS LATE INTO THE WEEK IN PLACES LIKE CHADRON AND SCOTTS
BLUFF. MODELS ALSO TRENDING DRIER THROUGH THIS PERIOD WITH
WESTERLY DOWNSLOPE FLOW BECOMING MORE LIKELY.
NUMERICAL MODELS ARE STRUGGLING TO RESOLVE THE MOVEMENT OF AN
UPPER LEVEL TROUGH OVER THE PACIFIC NORTHWEST LATE IN THE WEEK.
YESTERDAYS EC AND GFS BOTH WERE SHOWING THE TROUGH MOVING ACROSS
THE NORTHERN AND CENTRAL ROCKIES THIS UPCOMING WEEKEND. LAST
NIGHTS EC AND GFS BOTH INDICATED SPLITTING ENERGY WITH A CLOSED
LOW DEVELOPING OVER THE PACIFIC NORTHWEST WITH THE REST OF THE
ENERGY MOVING INTO CENTRAL CANADA. TODAYS MODEL RUNS ARE SOMEWHERE
IN BETWEEN. THE DIFFERENCE BETWEEN THE CLOSED LOW SOLUTION AND THE
PROGRESSIVE SOLUTION IS THE DIFFERENCE BETWEEN COOL AND WET AND
HOT AND DRY RESPECTIVELY. NOT REMOTELY CONFIDENT IN ANY SOLUTION
AT THIS TIME.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH MONDAY AFTERNOON)
GUSTY WEST TO SOUTHWEST WINDS FOR MOST OF SOUTHEAST WYOMING THIS
EVENING. WINDS WILL BECOME LIGHT AFTER 03Z. A FEW THUNDERSTORMS ARE
POSSIBLE THIS EVENING...AND MAY IMPACT KCDR OVER THE NEXT FEW HOURS.
OTHERWISE...OTHER LOCATIONS WILL REMAIN DRY WITH VFR CONDITIONS
THROUGH TONIGHT.
&&
.FIRE WEATHER...
ISSUED AT 250 PM MDT SUN JUL 12 2015
WARM AND DRY CONDITIONS WILL CONTINUE THIS AFTERNOON THROUGH MUCH OF
THE DAY ON MON. ELEVATED CONDITIONS ARE OCCURRING OVER EAST CENTRAL
WYOMING WITH HUMIDITIES NEAR 15 PERCENT AND WIND GUSTS TO 25 MPH AT
LUSK...BUT THIS SHOULD IMPROVE SHORTLY. LIGHT WINDS ARE EXPECTED ON
MON WITH MINIMUM HUMIDITIES AROUND 20 PERCENT. THE BEST CHANCE FOR
WETTING RAINS WILL ARRIVE ON TUE WITH SCATTERED TO NUMEROUS SHOWERS
AND THUNDERSTORMS LIKELY ACROSS MUCH OF THE AREA.
&&
.CYS WATCHES/WARNINGS/ADVISORIES...
WY...NONE.
NE...NONE.
&&
$$
UPDATE...MAJ
SHORT TERM...CLH
LONG TERM...SML
AVIATION...TJT
FIRE WEATHER...CLH
AREA FORECAST DISCUSSION
NWS CHEYENNE WY
545 PM MDT SUN JUL 12 2015
.SHORT TERM...(THIS AFTERNOON THROUGH TUESDAY NIGHT)
ISSUED AT 258 PM MDT SUN JUL 12 2015
LOW-LEVEL CUMULUS CONTINUES TO EXPAND IN BOTH COVERAGE AND VERTICAL
EXTENT THIS AFTERNOON AS CONVECTIVE TEMPERATURES ARE REACHED. RECENT
TRENDS IN RADAR AND VISIBLE SATELLITE IMAGERY HAVE SHOWN DIFFICULTY
FOR CONVECTION TO INITIATE. THIS IS PARTIALLY DUE TO STRONG CAPPING
WITH H7 TEMPS AROUND +14 TO +16 DEG C AND LOW-LEVEL DRYING OWING TO
STRONG MIXING. THE MODELS DO NOT SHOW ANY QPF...AND THE HRRR OFFERS
LITTLE SUPPORT FOR THUNDERSTORMS TODAY. HOWEVER...OPTED TO MAINTAIN
SLIGHT CHANCE POPS THROUGH 00Z GIVEN THE RIGHT REAR QUADRANT OF A
110 KT H25 JET STREAK AND A MID-LEVEL VORT MAX OVERHEAD. SHORTWAVE
RIDGING AND RESULTANT SUBSIDENCE WILL KEEP THINGS DRY FROM TONIGHT
THROUGH MUCH OF THE DAY ON MON.
A WEAK FROPA IS STILL EXPECTED TO OCCUR ACROSS THE FAR NORTH EARLY
IN THE DAY ON MON...BUT THIS WILL HAVE LITTLE IMPACT ON OUR SENSIBLE
WEATHER AS WARM ADVECTION OCCURS BENEATH RIDGING ALOFT. THINK THIS
WILL KEEP CONVECTION SUPPRESSED OUTSIDE OF THE MOUNTAINS UNTIL AROUND
21-00Z. INCREASING MONSOONAL MOISTURE IN THE H7-H3 LAYER AND SEVERAL
DISTURBANCES EMBEDDED WITHIN SOUTHWEST FLOW ALOFT WILL ALLOW SHOWERS
AND THUNDERSTORMS TO DEVELOP EASTWARD ONTO THE PLAINS BY LATE AFTN
OR EARLY EVE. NAM/GFS BUFKIT SOUNDINGS SHOW BIG TIME DIFFERENCES IN
THE INSTABILITY PARAMETERS. THE NAM SHOWS 1500-2000 J/KG OF SBCAPE
OVER CYS ON MON AFTN...WHILE THE GFS SHOWS 200 J/KG AT MOST. 0 TO 6
KM SHEAR IS NOT IMPRESSIVE FROM EITHER MODEL...SO DO NOT EXPECT TO
SEE ANYTHING SEVERE. ANY STORMS THAT DEVELOP WILL HAVE THE POTENTIAL
FOR GUSTY WINDS GIVEN INVERTED-V PROFILES.
MOIST SOUTHWEST FLOW BECOMES BETTER ESTABLISHED ON TUE. THE INCREASE
IN MONSOONAL MOISTURE AND LARGE SCALE FORCING SHOULD PROMOTE FAIRLY
WIDESPREAD SHOWERS AND THUNDERSTORMS ACROSS THE CWA. MAINTAINED AT
LEAST SCATTERED POPS FOR MOST AREAS...HIGHEST IN THE MOUNTAINS. WEAK
FLOW ALOFT SUGGESTS LITTLE CONCERN FOR STRONGER CONVECTION DESPITE
MODERATE INSTABILITY WITH CAPES EXCEEDING 1000 J/KG. THE MODELS SHOW
THE COOLEST TEMPERATURES ALOFT ON TUE...BUT NOT MUCH DIFFERENT THAN
PREVIOUS DAYS. CONTINUED TO TREND COOLER FOR HIGHS GIVEN THAT SHOWER
ACTIVITY AND MID LEVEL CLOUD COVER SHOULD BE MORE WIDESPREAD.
.LONG TERM...(WEDNESDAY THROUGH SUNDAY)
ISSUED AT 258 PM MDT SUN JUL 12 2015
MODELS TRENDING WARMER INTO THE EXTENDED FORECAST PERIOD AS
WESTERLY FLOW ALOFT DEVELOPS OVER SOUTHEAST WYOMING AND
PANHANDLE. TEMPERATURES WILL RISE INTO THE 80S OVER MUCH OF
SOUTHEAST WYOMING FROM MID WEEK INTO THE EARLY WEEKEND WITH SOME
90S INTO THE PLAINS. 90 DEGREE HIGHS LIKELY FOR THE NEBRASKA
PANHANDLE AND WOULD NOT BE SURPRISED TO SEE A SOME 100 DEGREE
READINGS LATE INTO THE WEEK IN PLACES LIKE CHADRON AND SCOTTS
BLUFF. MODELS ALSO TRENDING DRIER THROUGH THIS PERIOD WITH
WESTERLY DOWNSLOPE FLOW BECOMING MORE LIKELY.
NUMERICAL MODELS ARE STRUGGLING TO RESOLVE THE MOVEMENT OF AN
UPPER LEVEL TROUGH OVER THE PACIFIC NORTHWEST LATE IN THE WEEK.
YESTERDAYS EC AND GFS BOTH WERE SHOWING THE TROUGH MOVING ACROSS
THE NORTHERN AND CENTRAL ROCKIES THIS UPCOMING WEEKEND. LAST
NIGHTS EC AND GFS BOTH INDICATED SPLITTING ENERGY WITH A CLOSED
LOW DEVELOPING OVER THE PACIFIC NORTHWEST WITH THE REST OF THE
ENERGY MOVING INTO CENTRAL CANADA. TODAYS MODEL RUNS ARE SOMEWHERE
IN BETWEEN. THE DIFFERENCE BETWEEN THE CLOSED LOW SOLUTION AND THE
PROGRESSIVE SOLUTION IS THE DIFFERENCE BETWEEN COOL AND WET AND
HOT AND DRY RESPECTIVELY. NOT REMOTELY CONFIDENT IN ANY SOLUTION
AT THIS TIME.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH MONDAY AFTERNOON)
GUSTY WEST TO SOUTHWEST WINDS FOR MOST OF SOUTHEAST WYOMING THIS
EVENING. WINDS WILL BECOME LIGHT AFTER 03Z. A FEW THUNDERSTORMS ARE
POSSIBLE THIS EVENING...AND MAY IMPACT KCDR OVER THE NEXT FEW HOURS.
OTHERWISE...OTHER LOCATIONS WILL REMAIN DRY WITH VFR CONDITIONS
THROUGH TONIGHT.
&&
.FIRE WEATHER...
ISSUED AT 250 PM MDT SUN JUL 12 2015
WARM AND DRY CONDITIONS WILL CONTINUE THIS AFTERNOON THROUGH MUCH OF
THE DAY ON MON. ELEVATED CONDITIONS ARE OCCURRING OVER EAST CENTRAL
WYOMING WITH HUMIDITIES NEAR 15 PERCENT AND WIND GUSTS TO 25 MPH AT
LUSK...BUT THIS SHOULD IMPROVE SHORTLY. LIGHT WINDS ARE EXPECTED ON
MON WITH MINIMUM HUMIDITIES AROUND 20 PERCENT. THE BEST CHANCE FOR
WETTING RAINS WILL ARRIVE ON TUE WITH SCATTERED TO NUMEROUS SHOWERS
AND THUNDERSTORMS LIKELY ACROSS MUCH OF THE AREA.
&&
.CYS WATCHES/WARNINGS/ADVISORIES...
WY...NONE.
NE...NONE.
&&
$$
SHORT TERM...CLH
LONG TERM...SML
AVIATION...TJT
FIRE WEATHER...CLH
AREA FORECAST DISCUSSION
NWS CHEYENNE WY
352 PM MDT SAT JUL 11 2015
.SHORT TERM...(THIS EVENING THROUGH MONDAY NIGHT)
ISSUED AT 328 PM MDT SAT JUL 11 2015
ISOLATED TO WIDELY SCATTERED SHOWERS AND THUNDERSTORMS ARE CURRENTLY
DEVELOPING ALONG THE I80 CORRIDOR IN SOUTHEAST WYO. EXPECT THAT SOME
OF THIS ACTIVITY WILL SPREAD EASTWARD INTO THE SOUTHERN PANHANDLE IN
THE NEXT FEW HOURS WITH LINGERING OUTFLOW BOUNDARIES FROM CONVECTION
EARLIER THIS AM. LLVL MOISTURE IS MODEST...BUT DEW POINTS IN THE 40S
ARE CONTRIBUTING TO SBCAPES AROUND 500-1000 J/KG PER THE LATEST MESO
ANALYSIS FROM SPC. WILL MAINTAIN SLIGHT CHANCE POPS THROUGH 03Z...AT
WHICH POINT THE HRRR HAS CONSISTENTLY SHUT THINGS OFF. DO NOT EXPECT
TO SEE ANYTHING SEVERE TODAY WITH WEAK VERTICAL SHEAR...BUT SOME OF
THE STORMS COULD PRODUCE GUSTY WINDS WITH INVERTED-V TYPE SOUNDINGS
IN THE DRIER SFC ENVIRONMENT ALONG/WEST OF THE LARAMIE RANGE.
SUNDAY APPEARS TO BE THE MOST LIKELY DAY TO BE FREE OF ANY SHOWER OR
THUNDERSTORM ACTIVITY OUTSIDE OF THE MOUNTAINS. SEVERAL WEAK MIDLVL
DISTURBANCES WILL TRAVERSE THE FLOW...BUT H7-H3 MOISTURE PROGS FROM
THE GFS/NAM/ECM ARE CONSIDERABLY DRIER THAN TODAY IN ADVANCE OF AN
APPROACHING SHORTWAVE RIDGE. THE MODELS ARE GENERALLY DRY...EXCEPT
THE ECMWF WHICH PAINTS SOME LIGHT QPF SPREADING OVER THE PLAINS IN
THE 18Z-00Z TIME FRAME. GUIDANCE HAS HAD A TOUGH TIME RECENTLY WITH
THE MOIST LLVL ENVIRONMENT AND SMALL-SCALE FORCING MECHANISMS...SO
HONESTLY WOULD NOT BE SURPRISED IF LATER SHIFTS NEED TO MENTION THE
POSSIBILITY OF A TSTM OR TWO ON THE PLAINS IN THE LATE AFTN. IT WILL
BE MUCH WARMER ALOFT THOUGH...SO CAPPING WILL PLAY A ROLE. SHOULD BE
QUITE WARM TOMORROW WITH H7 TEMPS +14 TO +16 C.
.LONG TERM...(TUESDAY THROUGH SATURDAY)
ISSUED AT 348 PM MDT SAT JUL 11 2015
CHANCES FOR SHOWERS AND THUNDERSTORMS WILL CONTINUE THROUGH MUCH
OF NEXT WEEK BUT THERE WILL BE SOME CHANGES TO THE OVERALL WEATHER
PATTERN. UPPER LEVEL RIDGE AXIS WILL SHIFT INTO THE PLAINS WITH
SOUTHWEST FLOW OVER THE CENTRAL ROCKIES EARLY NEXT WEEK.
RELATIVELY MOIST SOUTHWEST FLOW WILL PUMP MOISTURE ALONG WITH
CHANCES FOR SHOWERS AND THUNDERSTORMS INTO THE FORECAST AREA.
TOUGH TO PINPOINT WHEN THE MAIN CHANCES FOR PRECIPITATION WILL
OCCUR GIVEN THAT SMALL DISTURBANCE EMBEDDED IN SOUTHWEST FLOW WILL
BE THE MAIN TRIGGERS FOR PRECIPITATION. TIMING OF THESE SUBTLE
DISTURBANCES IS VERY DIFFICULT FOR THE NUMERICAL MODELS TO
DETERMINE WITH GREAT ACCURACY.
BY MID NEXT WEEK THE RIDGE LOOKS TO FLATTEN WITH ZONAL FLOW OVER
THE WESTERN CONUS. SEVERAL EMBEDDED DISTURBANCES WILL CONTINUE TO
MOVE OVER THE AREA BRINGING MORE CHANCES FOR SHOWERS AND
THUNDERSTORMS. LATE IN THE WEEK BOTH THE ECMWF AND GFS ARE SHOWING
AN UNSEASONABLY STRONG TROUGH DIGGING INTO THE PACIFIC NORTHWEST.
THIS TROUGH MAY IMPACT THE FORECAST AREA BY NEXT WEEKEND...
BRINGING CONTINUED CHANCES FOR PRECIPITATION AND THE POTENTIAL FOR
A VERY COOL SHOT OF AIR FOR MID JULY.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON)
ISSUED AT 1156 AM MDT SAT JUL 11 2015
ISOLATED THUNDERSTORMS WILL MOVE ACROSS PORTIONS OF SOUTHEAST
WYOMING THIS AFTERNOON/EARLY EVENING WITH A FEW THUNDERSTORMS ALSO
POSSIBLE INTO THE NEBRAKSA PANHANDLE. ERRATIC GUSTY WINDS WILL BE
THE MAIN AVIATION THREAT IN THE VICINITY OF THESE STORMS.
THUNDERSTORM ACTIVITY WILL RAPIDLY DECREASE THROUGH THE EVENING
HOURS.
&&
.FIRE WEATHER...
ISSUED AT 313 PM MDT SAT JUL 11 2015
ISOLATED SHOWERS AND THUNDERSTORMS WILL REMAIN POSSIBLE THROUGH THE
LATE AFTN AND EARLY EVE HOURS. THE PRIMARY HAZARD FROM THIS ACTIVITY
WILL BE GUSTY AND ERRATIC WIND GUSTS. WARMER CONDITIONS ARE EXPECTED
FOR SUNDAY WITH MINIMUM HUMIDITY VALUES AROUND 20 PERCENT. THE NEXT
CHANCE FOR MORE WIDESPREAD PRECIPITATION WILL ARRIVE LATE MON INTO
TUE.
&&
.CYS WATCHES/WARNINGS/ADVISORIES...
WY...NONE.
NE...NONE.
&&
$$
SHORT TERM...CLH
LONG TERM...SML
AVIATION...SML
FIRE WEATHER...CLH
AREA FORECAST DISCUSSION
NWS CHEYENNE WY
1200 PM MDT SAT JUL 11 2015
.UPDATE...
ISSUED AT 1006 AM MDT SAT JUL 11 2015
MINOR UPDATE TO ADD LOW-END POPS ACROSS SOUTHEAST WY AND THE
SOUTHERN NEB PANHANDLE THIS AFTN/EVE. THE MAJORITY OF GUIDANCE
SUGGESTS DRY CONDITIONS OUTSIDE OF THE MOUNTAINS...BUT THERE IS
STILL DECENT LLVL MOISTURE WITH DEWPOINTS IN THE 45 TO 55 DEGREE
RANGE. INSTABILITY WILL BE PRESENT AS WELL WITH THE NAM SHOWING
CAPE VALUES AROUND 1000 J/KG. WEAK DISTURBANCES EMBEDDED WITHIN
MOIST SOUTHWESTERLY FLOW ALOFT...COMBINED WITH LLVL FORCING ALONG
RESIDUAL BOUNDARIES FROM MORNING CONVECTION MAY RESULT IN ISOLATED
TO WIDELY SCATTERED SHOWERS/TSTMS OVER THE PLAINS. RECENT RUNS OF
THE HRRR WOULD SUGGEST THIS AS WELL. UPDATES HAVE BEEN SENT.
&&
.SHORT TERM...(TODAY THROUGH MONDAY)
ISSUED AT 300 AM MDT SAT JUL 11 2015
SHOWERS AND T-STORMS DEVELOPED EARLIER TONIGHT IN NORTHEAST COLORADO
AND SPREAD ACROSS EXTREME SOUTHEAST WYOMING AND THE WESTERN
NEBRASKA PANHANDLE. SUSPECT THIS ACTIVITY INITIATED ALONG A MID
LEVEL BOUNDARY SITUATED WEST-EAST NEAR THE TRI-STATE BORDER AND WAS
SUPPORTED BY ELEVATED INSTABILITY AND WEAK VORTICITY MOVING
OVERHEAD. SHOULD SEE THIS ACTIVITY DISSIPATE BY SUNRISE AS IT MOVES
OFF TO THE EAST WITH THE REMAINDER OF THE MORNING REMAINING
MOSTLY DRY.
TODAY WILL FEATURE A STRENGTHENING SOUTHWEST JET OVER THE GREAT
BASIN AND CENTRAL ROCKIES WITH PACIFIC MOISTURE AND SEVERAL WEAK
DISTURBANCES MOVING OVER THE CWA. IT SEEMS MORE LIKELY WE WILL HAVE
SHOWERS AND STORMS DEVELOP OVER THE MOUNTAINS THIS AFTERNOON AND
SHIFT OFF TO THE EAST-NORTHEAST IN THE LATE AFTERNOON AND PERHAPS
THE EVENING. TEMPS AT H7 WILL INCREASE TO 13-14C BY 00Z THO WHICH
SHOULD MINIMIZE CONVECTIVE POTENTIAL FURTHER EAST AWAY FROM THE
MOUNTAINS. SO MAINTAINED FOCUS FOR POPS IN THE MOUNTAINS AND NEARBY
LOWER ELEVATIONS...WITH AN ISOLATED COVERAGE FOR STORMS ANTICIPATED
DUE TO OVERALL LOW INSTABILITY.
SUNDAY EXHIBITS A FAIR AMOUNT OF UNCERTAINTY REGARDING T-STORM
POTENTIAL. LOOKING AT GOOD UPPER LEVEL SUPPORT FROM A 100 KT JET
WHILE A SHORTWAVE TROUGH MOVES OVERHEAD IN THE AFTERNOON. BREEZY
WESTERLY WINDS ARE ANTICIPATED AT THE SFC THO...LEAVING LITTLE IN
TERMS OF SFC FORCING OTHER THAN GENERAL OROGRAPHICS. ALSO...MODELS
SHOW A DRY PUNCH ADVECTING OVERHEAD IN THE AFTERNOON WHICH IS NOT
FAVORABLE FOR CONVECTIVE DEVELOPMENT SO KEPT CONDITIONS MOSTLY DRY
EXCEPT FOR A FEW MOUNTAINS STORMS.
MONSOONAL MOISTURE WILL VISIT THE CENTRAL ROCKIES ON MONDAY SO
EXPECT TYPICAL HIGH BASED STORMS TO OCCUR OVER THE MOUNTAINS AND
NEARBY HIGH VALLEYS. WEAK WESTERLY SFC WINDS LOOK TO REMAIN IN PLACE
ACROSS THE PLAINS...SO NOT ANTICIPATING MUCH ACTIVITY OVER THIS AREA
EXCEPT PERHAPS A STRAY SHOWER THAT CAN SURVIVE OFF THE MOUNTAINS.
TEMPERATURES THROUGH THE WEEKEND WILL REMAIN QUITE WARM WITH THE
HOTTEST DAY ON SUNDAY WITH MID 80-90S ACROSS THE EAST AND 70S-80S IN
THE HIGH COUNTRY.
.LONG TERM...(MONDAY NIGHT THROUGH FRIDAY)
ISSUED AT 300 AM MDT SAT JUL 11 2015
WITH SOUTHWESTERLY FLOW ALOFT IN PLACE ON TUES...BOTH THE GFS AND
ECMWF INDICATE AN INCREASE IN MONSOONAL MOISTURE AS 700-500MB RH
VALUES COME UP. THUS WILL SEE AN INCREASE IN AFTN AND EVENING
CONVECTION ON TUES. WILL FCST ISOLATED TO SCATTERED COVERAGE OF
STORMS FOR NOW. STRONG STORMS DO NOT APPEAR LIKELY WITH RATHER
LIMITED INSTABILITY/SHEAR. THE GFS DOES SHOW SOME DRYING BY WED
WHEREAS THE ECMWF KEEPS THE MIDLVL MOISTURE PLUME OVERHEAD FOR ONE
MORE DAY. AN UPPER TROUGH IS PROGGED TO AMPLIFY INTO THE NORTHERN
ROCKIES BY THURS WITH FLOW ALOFT BECOMING MORE
WESTERLY ACROSS WYOMING...BRINGING IN SOME DRYING AND REDUCED
CHANCES FOR TSTMS. COULD SEE A COLD FRONTAL PASSAGE BY THURS
NIGHT/FRI MORNING AS THE TROUGH PROGRESSES EASTWARD OVER MONTANA.
TEMPS THROUGH THE EXTENDED WILL BE AROUND NORMAL FOR MID JULY.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON)
ISSUED AT 1156 AM MDT SAT JUL 11 2015
ISOLATED THUNDERSTORMS WILL MOVE ACROSS PORTIONS OF SOUTHEAST
WYOMING THIS AFTERNOON/EARLY EVENING WITH A FEW THUNDERSTORMS ALSO
POSSIBLE INTO THE NEBRAKSA PANHANDLE. ERRATIC GUSTY WINDS WILL BE
THE MAIN AVIATION THREAT IN THE VICINITY OF THESE STORMS.
THUNDERSTORM ACTIVITY WILL RAPIDLY DECREASE THROUGH THE EVENING
HOURS.
&&
.FIRE WEATHER...
ISSUED AT 300 AM MDT SAT JUL 11 2015
ISOLATED SHOWERS AND THUNDERSTORMS ARE POSSIBLE MAINLY DURING THE
AFTERNOON HOURS THIS WEEKEND WITH THE FOCUS FOR ACTIVITY OVER THE
MOUNTAINS. WESTERLY WINDS WILL BE BREEZY OVER MUCH OF THE DISTRICT
BUT AFTERNOON HUMIDITIES SHOULD REMAIN IN THE UPPER TEENS TO UPPER
20S.
&&
.CYS WATCHES/WARNINGS/ADVISORIES...
WY...NONE.
NE...NONE.
&&
$$
UPDATE...CLH
SHORT TERM...RJM
LONG TERM...ZF
AVIATION...SML
FIRE WEATHER...RJM
AREA FORECAST DISCUSSION
NWS CHEYENNE WY
1014 AM MDT SAT JUL 11 2015
.UPDATE...
ISSUED AT 1006 AM MDT SAT JUL 11 2015
MINOR UPDATE TO ADD LOW-END POPS ACROSS SOUTHEAST WY AND THE
SOUTHERN NEB PANHANDLE THIS AFTN/EVE. THE MAJORITY OF GUIDANCE
SUGGESTS DRY CONDITIONS OUTSIDE OF THE MOUNTAINS...BUT THERE IS
STILL DECENT LLVL MOISTURE WITH DEWPOINTS IN THE 45 TO 55 DEGREE
RANGE. INSTABILITY WILL BE PRESENT AS WELL WITH THE NAM SHOWING
CAPE VALUES AROUND 1000 J/KG. WEAK DISTURBANCES EMBEDDED WITHIN
MOIST SOUTHWESTERLY FLOW ALOFT...COMBINED WITH LLVL FORCING ALONG
RESIDUAL BOUNDARIES FROM MORNING CONVECTION MAY RESULT IN ISOLATED
TO WIDELY SCATTERED SHOWERS/TSTMS OVER THE PLAINS. RECENT RUNS OF
THE HRRR WOULD SUGGEST THIS AS WELL. UPDATES HAVE BEEN SENT.
&&
.SHORT TERM...(TODAY THROUGH MONDAY)
ISSUED AT 300 AM MDT SAT JUL 11 2015
SHOWERS AND T-STORMS DEVELOPED EARLIER TONIGHT IN NORTHEAST COLORADO
AND SPREAD ACROSS EXTREME SOUTHEAST WYOMING AND THE WESTERN
NEBRASKA PANHANDLE. SUSPECT THIS ACTIVITY INITIATED ALONG A MID
LEVEL BOUNDARY SITUATED WEST-EAST NEAR THE TRI-STATE BORDER AND WAS
SUPPORTED BY ELEVATED INSTABILITY AND WEAK VORTICITY MOVING
OVERHEAD. SHOULD SEE THIS ACTIVITY DISSIPATE BY SUNRISE AS IT MOVES
OFF TO THE EAST WITH THE REMAINDER OF THE MORNING REMAINING
MOSTLY DRY.
TODAY WILL FEATURE A STRENGTHENING SOUTHWEST JET OVER THE GREAT
BASIN AND CENTRAL ROCKIES WITH PACIFIC MOISTURE AND SEVERAL WEAK
DISTURBANCES MOVING OVER THE CWA. IT SEEMS MORE LIKELY WE WILL HAVE
SHOWERS AND STORMS DEVELOP OVER THE MOUNTAINS THIS AFTERNOON AND
SHIFT OFF TO THE EAST-NORTHEAST IN THE LATE AFTERNOON AND PERHAPS
THE EVENING. TEMPS AT H7 WILL INCREASE TO 13-14C BY 00Z THO WHICH
SHOULD MINIMIZE CONVECTIVE POTENTIAL FURTHER EAST AWAY FROM THE
MOUNTAINS. SO MAINTAINED FOCUS FOR POPS IN THE MOUNTAINS AND NEARBY
LOWER ELEVATIONS...WITH AN ISOLATED COVERAGE FOR STORMS ANTICIPATED
DUE TO OVERALL LOW INSTABILITY.
SUNDAY EXHIBITS A FAIR AMOUNT OF UNCERTAINTY REGARDING T-STORM
POTENTIAL. LOOKING AT GOOD UPPER LEVEL SUPPORT FROM A 100 KT JET
WHILE A SHORTWAVE TROUGH MOVES OVERHEAD IN THE AFTERNOON. BREEZY
WESTERLY WINDS ARE ANTICIPATED AT THE SFC THO...LEAVING LITTLE IN
TERMS OF SFC FORCING OTHER THAN GENERAL OROGRAPHICS. ALSO...MODELS
SHOW A DRY PUNCH ADVECTING OVERHEAD IN THE AFTERNOON WHICH IS NOT
FAVORABLE FOR CONVECTIVE DEVELOPMENT SO KEPT CONDITIONS MOSTLY DRY
EXCEPT FOR A FEW MOUNTAINS STORMS.
MONSOONAL MOISTURE WILL VISIT THE CENTRAL ROCKIES ON MONDAY SO
EXPECT TYPICAL HIGH BASED STORMS TO OCCUR OVER THE MOUNTAINS AND
NEARBY HIGH VALLEYS. WEAK WESTERLY SFC WINDS LOOK TO REMAIN IN PLACE
ACROSS THE PLAINS...SO NOT ANTICIPATING MUCH ACTIVITY OVER THIS AREA
EXCEPT PERHAPS A STRAY SHOWER THAT CAN SURVIVE OFF THE MOUNTAINS.
TEMPERATURES THROUGH THE WEEKEND WILL REMAIN QUITE WARM WITH THE
HOTTEST DAY ON SUNDAY WITH MID 80-90S ACROSS THE EAST AND 70S-80S IN
THE HIGH COUNTRY.
.LONG TERM...(MONDAY NIGHT THROUGH FRIDAY)
ISSUED AT 300 AM MDT SAT JUL 11 2015
WITH SOUTHWESTERLY FLOW ALOFT IN PLACE ON TUES...BOTH THE GFS AND
ECMWF INDICATE AN INCREASE IN MONSOONAL MOISTURE AS 700-500MB RH
VALUES COME UP. THUS WILL SEE AN INCREASE IN AFTN AND EVENING
CONVECTION ON TUES. WILL FCST ISOLATED TO SCATTERED COVERAGE OF
STORMS FOR NOW. STRONG STORMS DO NOT APPEAR LIKELY WITH RATHER
LIMITED INSTABILITY/SHEAR. THE GFS DOES SHOW SOME DRYING BY WED
WHEREAS THE ECMWF KEEPS THE MIDLVL MOISTURE PLUME OVERHEAD FOR ONE
MORE DAY. AN UPPER TROUGH IS PROGGED TO AMPLIFY INTO THE NORTHERN
ROCKIES BY THURS WITH FLOW ALOFT BECOMING MORE
WESTERLY ACROSS WYOMING...BRINGING IN SOME DRYING AND REDUCED
CHANCES FOR TSTMS. COULD SEE A COLD FRONTAL PASSAGE BY THURS
NIGHT/FRI MORNING AS THE TROUGH PROGRESSES EASTWARD OVER MONTANA.
TEMPS THROUGH THE EXTENDED WILL BE AROUND NORMAL FOR MID JULY.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SUNDAY MORNING)
ISSUED AT 549 AM MDT SAT JUL 11 2015
VFR CONDITIONS THROUGH THE TAF PERIOD. RAIN SHOWERS ARE EXPECTED
TO CONTINUE AT SNY OVER THE NEXT FEW HOURS BEFORE TAPERING OFF.
CUMULUS WILL DEVELOP BY EARLY AFTERNOON...HOWEVER THE CHANCE OF
TSTMS IS QUITE SMALL SO WILL KEEP OUT OF THE TAF. SOUTHWEST WINDS
WILL GUST TO 20-30 KTS TO THE WEST OF THE LARAMIE RANGE DURING THE
AFTERNOON.
&&
.FIRE WEATHER...
ISSUED AT 300 AM MDT SAT JUL 11 2015
ISOLATED SHOWERS AND THUNDERSTORMS ARE POSSIBLE MAINLY DURING THE
AFTERNOON HOURS THIS WEEKEND WITH THE FOCUS FOR ACTIVITY OVER THE
MOUNTAINS. WESTERLY WINDS WILL BE BREEZY OVER MUCH OF THE DISTRICT
BUT AFTERNOON HUMIDITIES SHOULD REMAIN IN THE UPPER TEENS TO UPPER
20S.
&&
.CYS WATCHES/WARNINGS/ADVISORIES...
WY...NONE.
NE...NONE.
&&
$$
UPDATE...CLH
SHORT TERM...RJM
LONG TERM...ZF
AVIATION...ZF
FIRE WEATHER...RJM
AREA FORECAST DISCUSSION
NWS TALLAHASSEE FL
345 AM EDT MON JUL 13 2015
.Near Term [Through Today]...
The synoptic pattern this morning generally consists of a large
upper ridge centered over the Southern Plains, with a shortwave
trough axis slicing through the Northeast, then continuing
southeast off the Mid-Atlantic coast. At the surface, a very weak
pressure pattern is observed where hot afternoon temperatures
generated broad troughing across the Southeast, which has been
further disturbed by clusters of convection. A 06z subjective
analysis did pick up on a weak surface trough laid out southwest
to northeast from near Ft. Benning through Augusta. Outflow from
waning convection in this area may get just enough convergence
along this trough to generate a few scattered storms through the
remainder of the night, though a continued dissipating trend is
expected.
Ridging aloft, northwest steering flow, and no local synoptic
forcing should favor the lower coverage, type 8 seabreeze regime
this afternoon. While the overall coverage will be rather low,
near to slightly above climo PoPs will sprawl west to east across
north Florida (primarily south of Interstate-10). A large area of
SBCAPE at least 4000J/kg is analyzed offshore in the northeast
Gulf this morning. As flow turns onshore early this afternoon in
the seabreeze zone, this plume of high CAPE will be advected
towards the coast, and possibly inland along the immediate coast
(especially the southeast Big Bend). The 06z RAP depicts 4500J/kg
SBCAPE along the Taylor and Dixie coastline late this afternoon.
Thus, with the typical late storm development in this regime and
little inland penetration to the seabreeze fronts, expect the
possibility for some strong to severe storms later today. The
strongest storms will likely be near the coast or just offshore.
Additionally, with plentiful instability behind the seabreeze,
expect outflow to continue to initiate storms into the early
evening.
High temperatures will be quite hot once again today, probably
only a degree or so below yesterday`s temperatures. Heat indices
will likely remain in the 103-106 range today, which do not
warrant an advisory though caution should still be exercised if
outdoors today.
.Short Term [Tonight Through Wednesday]...
The synoptic pattern east of the Rockies will not change
appreciably over the first half of the work week, with a stout
mid-upper level high remaining centered over the Arklatex. This
will set up northwesterly flow aloft from the Great Lakes to the
Southeast, and raises the possibility of some effects from
upstream convection even this far south. Essentially all the
models show some +PV anomalies propagating southeast along the
periphery of the ridge, with some passing through or very near our
forecast area. However, the timing is somewhat inconsistent, and
models tend to struggle handling convection in persistent
northwest flow regimes over the eastern US. However, these flow
patterns do usually yield at least one or two MCVs, outflow
boundaries, or shortwaves that reach our area and enhance
convective intensity, organization, and coverage. Due to timing
uncertainties, we maintained higher PoPs at night over land areas
than would be climatologically likely this time of year. It`s
worth noting that there is fairly good agreement amongst the
models in showing a stronger shortwave reaching the Carolinas and
eastern Georgia by late Wednesday. The Storm Prediction Center has
outlined a slight risk of severe storms for later Wednesday across
parts of our area, so that may be a period when our area could see
some more organized thunderstorms.
While high temperatures may return closer to seasonal normals in
the low-mid 90s, models indicate higher afternoon dewpoints -
possibly remaining in the mid 70s in some areas. This should
continue to produce widespread heat indices around 105 degrees,
with a few areas possibly approaching Heat Advisory criteria. This
will need to be monitored, although the aforementioned uncertainty
surrounding convective timing makes it difficult to identify any
specific area or day that would be more likely to see those sort
of conditions.
.Long Term [Wednesday Night Through Monday]...
The upper level ridge will remain centered over the Arklatex
region through the extended period, which should continue to place
the forecast area in N-NW flow. This traditionally favors higher
rain chances in our Florida zones, although any areas of organized
convection that initiate north of our area could also push south
and affect more of the forecast area. The forecast continues to
indicate a chance of showers and storms each day, with highs
remaining slightly above normal - in the mid 90s. Models indicate
a continuation of elevated dewpoints during the daytime hours, so
heat indices should continue to regularly be above 100 degrees.
&&
.Aviation...
[Through 06Z Tuesday] VFR conditions are expected through the TAF
period, the only exception will be in thunderstorms. Current
thinking gives ECP the best chance for storms today, though a
storm cant be ruled out at TLH and VLD late in the afternoon.
&&
.Marine...
West winds will begin to increase later on Tuesday, with SCEC
level winds possible from Tuesday Night to Thursday Night. 15-20
knot winds are above the climatological normal for this time of
year, especially lingering for such a long period of time. In
addition, expected large atmospheric instability levels over the
coastal waters will contribute to a persistent threat of severe
winds from thunderstorms over the waters. Mariners should be
prepared for stronger winds and choppier seas than are normally
expected in July, as well as the possibility of some significant
storms over the waters this week.
&&
.Fire Weather...
Hazardous fire weather conditions are not expected over the next
several days.
&&
.Hydrology...
Area rivers remain below bankfull levels. Scattered showers and
storms are expected this week, but heavy rainfall should be
relatively localized. Flooding is not expected on any of the
larger area rivers.
&&
.Preliminary Point Temps/PoPs...
Tallahassee 98 76 94 75 94 / 30 40 60 30 50
Panama City 93 81 90 80 90 / 30 20 40 30 40
Dothan 97 76 97 77 95 / 20 30 40 30 40
Albany 98 75 97 75 94 / 20 30 40 30 40
Valdosta 100 74 94 74 95 / 40 40 60 30 50
Cross City 95 76 90 76 92 / 50 30 50 30 50
Apalachicola 92 80 90 80 91 / 40 20 40 30 40
&&
.TAE WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
GA...NONE.
AL...NONE.
GM...NONE.
&&
$$
NEAR TERM...HARRIGAN
SHORT TERM...LAMERS
LONG TERM...LAMERS
AVIATION...HARRIGAN
MARINE...LAMERS
FIRE WEATHER...HARRIGAN
HYDROLOGY...LAMERS
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
459 AM CDT MON JUL 13 2015
.MESOSCALE DISCUSSION..450 AM CDT
THE MCS OVER SOUTHERN WISCONSIN HAS SHOWN A STRENGTHENING TREND
OVER THE PAST 90 MINUTES OR SO AS IT CONTINUES TO MOVE SOUTHEAST.
IT APPEARS A SECOND MCV /AFTER THE FIRST NOW IN NORTHEAST WI/ HAS
DEVELOPED JUST NORTHWEST OF THE MILWAUKEE METRO AND IS A SIGN OF
SOME LONGEVITY OF THE CURRENT SEVERE WEATHER THREAT. THE OVERALL
COMPLEX CONTINUES TO MOVE SOUTHEAST...ALTHOUGH THE MOST INTENSE
CELLS/BOWS/INTERACTIONS HAVE MAINLY BEEN PROPAGATING EAST. THIS IS
LIKELY DUE TO THE BETTER ORIENTATION OF THE 0-1KM AND 0-3KM SHEAR
VECTORS AS INDICATED BY THE RAP MODEL. IN THESE AREAS...ISOLATED
DAMAGING WIND SPEEDS HAVE BEEN OBSERVED PER LSRS FROM WFO MKX. THE
LOW-LEVEL WIND SHEAR MAGNITUDE ON THE WFO MKX VAD PROFILE AND SPC
RAP ANALYSIS /25-30 KT IN 0-1KM DEPTH/ AS WELL AS INDICATIONS THAT
THE BOUNDARY LAYER IS MIXED AHEAD OF THE LINE...DO INDICATE THE
POSSIBILITY OF A BRIEF TORNADO AS WELL...AND HAVE SEEN TEMPORARY
RADAR SIGNATURES INDICATING ROTATION.
OVERALL EXPECT THE MCS TO PROPAGATE SOUTHEASTWARD THROUGH THE
FORECAST AREA...INCLUDING MOVING THROUGH THE CHICAGO METRO AREA
BETWEEN 6 AM AND 730 AM. WHILE THE SEVERE THREAT IS EXPECTED TO
BE ISOLATED TO SCATTERED WITHIN THE LINE...FAIRLY WIDESPREAD 40-45
MPH GUSTS ARE LIKELY ESPECIALLY NORTH OF I-80 THROUGH 6-7 A.M PER
UPSTREAM OBSERVATIONS.
MTF
&&
.SHORT TERM...
400 AM CDT
THROUGH WEDNESDAY NIGHT...
SEVERE & FLASH FLOOD THREAT TODAY/TONIGHT & HEAT/HUMIDITY TODAY...
EXTREMELY COMPLEX FORECAST THE REST OF TODAY INTO TONIGHT AND ONE
THAT INCLUDES THE POTENTIAL FOR HIGHER END SEVERE WEATHER OF ALL
HAZARDS. ALSO SOME OPPRESSIVE HEAT POSSIBLY IN THE MIX. THE DEVIL
IS IN THE DETAILS...AND MESOSCALE EVOLUTION TODAY WILL IMPACT
MAGNITUDE AND LOCATION OF SEVERE THREAT...AS WELL AS TEMPS AND
HEAT INDEX VALUES ATTAINED. EVEN WITH LOWER CONFIDENCE DUE TO
UNCERTAINTY IN CONVECTIVE EVOLUTION TODAY...WILL BE ISSUING A HEAT
ADVISORY FOR THE SOUTHWEST THIRD OF THE CWA.
THE BIG QUESTION IS WHAT HAPPENS BEYOND THE ONGOING MCS TO OUR
NORTH THAT WILL LIKELY AFFECT ALL IF NOT MOST OF THE CWA THIS
MORNING AND THEN COULD SHIFT SOUTHEAST OF THE CWA BY MID DAY. FOR
ADDITIONAL DETAILS ON MCS AND ASSOCIATED SEVERE/HEAVY RAIN
POTENTIAL...REFER TO MESOSCALE DISCUSSION. FOR HI-RES CONVECTIVE
ALLOWING GUIDANCE THAT ASSISTED IN NEAR TERM PORTION OF
FORECAST...REFERRED TO MORE CONSISTENT 4KM NAM AND ARW/NMM-EAST.
HAVE DISCOUNTED HRRR/RAP AND WILD RUN TO RUN VARIATION EXHIBITED.
CONCEPTUALLY...EXPECTATION FOR MCS AND ASSOCIATED SHORTWAVE/SPEED
MAX TO PROPAGATE SOUTHEAST WOULD PUT US IN A SUBSIDENT REGIME FROM
THE MID-LATE MORNING INTO THE EARLY AFTERNOON. THERE WILL BE
DISRUPTION OF WIND FIELD AND CANNOT RULE OUT A WAKE LOW...AS WELL
AS PERIOD OF ONSHORE FLOW SLOWING TEMPERATURE RISE ALONG
LAKESHORE. IF NO BACKBUILDING OF MCS OCCURS...REMNANT OUTFLOW
BOUNDARIES ARE STILL LIKELY TO BE LEFT BEHIND. BUT TIMING OF WAVE
SHOULD ALLOW FOR CLOUD COVER TO DISSIPATE AND IMPRESSIVE EML
SAMPLED BY 00Z RAOBS TO OUR SOUTH AND WEST WILL BE ABLE TO FULLY
ADVECT EASTWARD. CLEARING/SUBSIDENCE WILL ALSO ALLOW WARM FRONT
CURRENTLY STRETCHING FROM SOUTHERN MN TO WEST CENTRAL IL TO LIFT
NORTHEAST. LAST 2 RUNS OF NAM12 HAVE REDEVELOPED CONVECTION AROUND
MID-DAY OVER CENTRAL CWA AND THEN PROPAGATED IT SOUTHEAST...WHICH
SLOWS RECOVERY PROCESS...BUT HAVE ALSO LARGELY DISCOUNTED THIS
SOLUTION.
ASSUMING WARM FRONT DOES LIFT NORTHEAST AND BRING CWA INTO WARM
SECTOR...OBS WEST OF THE BOUNDARY ON SUNDAY GENERALLY FEATURED
HIGHS IN THE UPPER 80S TO LOWER 90S AND DEWPOINTS IN THE UPPER 70S
TO AROUND 80. EXTREMELY WET SEASON SO FAR IN SOUTHERN CWA AND
EVAPOTRANSPIRATION FROM LARGE/MATURE CORN CROP LEADS ME TO BELIEVE
THAT AT LEAST A FEW SPOTS IN OUR SOUTHWEST CWA WILL REACH THESE 80
DEGREE/NEAR 80 DEWPOINTS THIS AFTERNOON. COUPLED WITH HIGHS NEAR
90...THIS WILL ENABLE HEAT INDEX VALUES TO PEAK IN 105 TO 110
RANGE...AND THUS ISSUED HEAT ADVISORY FROM LEE COUNTY TO IROQUOIS
COUNTY AND WEST. THE REST OF THE CWA SHOULD SEE PEAK HEAT INDEX
VALUES IN THE 95 TO 105 RANGE...WHICH IS STILL QUITE UNCOMFORTABLE
AND NOT SOMETHING COMMONLY EXPERIENCED THIS SUMMER SO FAR.
TEMP/DEWPOINT/CLOUD COVER FORECAST WILL THEN DICTATE WHETHER
INSTABILITY CAN BE MAXIMIZED OVER THE AREA...AND IF IT
DOES...MLCAPE VALUES OF AT LEAST 4000-5000 J/KG ARE POSSIBLE
THANKS TO HIGH DEWPOINTS AND STEEP MIDLEVEL LAPSE RATES. VOLATILE
AIRMASS WILL ALSO BE TOPPED BY NOSE OF UPPER LEVEL JET MAX OF
60-80 KT AND ABOUT 50 KT OF MIDLEVEL FLOW...PROVIDING 45-50 KT OF
NORTHWEST 0-6KM LAYER SHEAR THIS AFTERNOON INTO THIS EVENING. AT
LEAST ISOLATED TSRA CANNOT BE RULED OUT IN POSSIBLE LULL
PERIOD...BUT IF WE DO GET IT...REINITIATION OF TSRA IS EXPECTED TO
OCCUR LATE AFTERNOON INTO EARLY EVENING JUST TO WEST OR NORTHWEST
OF CWA. S0UTH-SOUTHWEST SURFACE WINDS...WESTERLY 850 MB WINDS OF
25-35 KT AND NORTHWEST MIDLEVEL WINDS WILL PROVIDE PLENTY OF
VEERING WITH HEIGHT. LOCATION OF INITIATION IS IN QUESTION...BUT
SUSPECT THAT APPROACHING COLD FRONT TRAILING FROM SURFACE LOW TO
NORTH...ASCENT FROM UPPER WAVE OVER UPPER MIDWEST AND ALSO
ELONGATED VORT MAX INTO WEST CENTRAL IL WILL BE ENOUGH TO BREAK
ANY CAPPING. ORIENTATION OF NORTHWEST SHEAR VECTOR TO INITIATING
BOUNDARY SHOULD RESULT IN AT LEAST INITIAL DISCRETE SUPERCELL
STORM MODE. THIS ALSO ADDS UNCERTAINTY TO POPS AS COVERAGE COULD
VERY WELL BE SCATTERED AND EVEN STAY SCATTERED IF EVOLUTION INTO
MCS/QLCS DOES NOT OCCUR THIS EVENING.
EXTREME INSTABILITY AND MORE THAN SUFFICIENT SHEAR...INCLUDING AT
THE LOW LEVELS...ESPECIALLY NEAR ANY LEFTOVER BOUNDARIES...MEANS
THAT EXPLOSIVE DEVELOPMENT AND ALL SEVERE HAZARDS ARE POSSIBLE.
THIS INCLUDES THE POTENTIAL FOR HIGH END DAMAGING WINDS/ESPECIALLY
IF TRANSITION TO A SEVERE MCS/QLCS OCCURS. IN ADDITION...DISCRETE
DEVELOPMENT REMAINING DOMINANT WOULD FAVOR POTENTIAL FOR
TORNADOES...INCLUDING A STRONG TORNADO OR TWO...AND LARGE TO VERY
LARGE HAIL. STORM MOTION WOULD FAVOR SOUTHEAST MOVEMENT INTO THE
MID TO LATE EVENING. IF SHORT WAVE APPROACHING FROM IA THIS
AFTERNOON ENDS UP BEING FOCUS FOR MORE WIDESPREAD
DEVELOPMENT...THIS COULD KEEP HIGHER END SEVERE THREAT OUT OF FAR
NORTHERN AND NORTHEAST IL AND EXTREME NORTHWEST INDIANA...AS PER
CURRENT DEPICTION OF MODERATE AND ENHANCED RISK FROM CWA. ANY
INTENSE CONVECTION WILL BE IN AN EXTREMELY MOIST AIRMASS...SO
EXCESSIVE RAIN RATES AND FLASH FLOODING WOULD BE LIKELY...AS IT
WONT TAKE MUCH WHETHER OVER INUNDATED SOUTHERN CWA OR URBAN AREAS.
NO CHANGES TO GOING FLASH FLOOD WATCH FOR THIS REASON. THE BOTTOM
LINE TODAY INTO TONIGHT IS STAY WEATHER AWARE...HAVE A WAY TO
RECEIVE WARNINGS...AND ALSO HAVE A SEVERE WEATHER SAFETY PLAN IN
PLACE AHEAD OF TIME SHOULD YOU NEED TO ACT. THERE ARE CERTAINLY
SCENARIOS IN WHICH CONVECTIVE EVOLUTION CAN STILL MODULATE OR EVEN
LESSEN SEVERE THREAT TODAY...BUT GIVEN PATTERN RECOGNITION OF
EXTREME CAPE AND SUFFICIENT SHEAR...SUSPECT AT LEAST PARTS OF CWA
WILL EXPERIENCE SEVERE WEATHER LATER TODAY INTO THIS EVENING AFTER
WHATEVER OCCURS THIS MORNING.
TUESDAY THROUGH WEDNESDAY NIGHT...
TUESDAY COULD FEATURE AT LEAST SCATTERED TSRA DEVELOPMENT AS
SECONDARY COLD FRONT/TROUGH AXIS INTERACTS WITH A STILL WARM AND
MOIST AIR MASS. COOLER AND DRIER AIR LOOKS TO MAKE A BRIEF RETURN
ON WEDNESDAY.
RC
&&
.LONG TERM...
342 AM CDT
THURSDAY THROUGH SUNDAY...
THE EMPHASIS ON THE FORECAST WAS CERTAINLY ON THE SHORT TERM THIS
MORNING SO HAVE GONE HEAVILY WITH A WELL-VERIFYING WEIGHTED MODEL
BLEND FOR MOST OF LATE WEEK AND NEXT WEEKEND. WARM ADVECTION IS
EXPECTED TO RETURN ON THURSDAY WITH BUILDING HEIGHTS AS THE BELT OF
UPPER LEVEL WESTERLIES UNDULATES NORTH. WITH BUILDING THICKNESSES
AND LIKELY INCREASING TEMPERATURES AND MOISTURE LATE IN THE
WEEK...DAILY QPF AND OUTPUT CHANCES OF STORMS ARE PRESENTLY
PROVIDED BY GUIDANCE...ALTHOUGH A PERIOD OF A DAY OR TWO OF
CAPPING LOOKS POSSIBLE...MAINLY FRIDAY-SATURDAY. TEMPERATURES
POSSIBLY COULD REACH THE 90S WITH 850MB TEMPERATURES FORECAST BY
THE NAEFS TO BE IN THE TOP 15 PERCENTILE FOR JULY BY SATURDAY.
MTF
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 09Z...
* PERIOD OF EARLY MORNING TSRA WITH IFR VISIBILITY CENTERED AROUND
DAYBREAK.
* WINDS BRIEFLY TURNING NORTHWEST AND GUSTING IN EXCESS OF 30 KT
WITH THE STORMS...WITH ISOLATED GUSTS IN EXCESS OF 45 KT
POSSIBLE.
* MVFR CIGS DEVELOPING PRIOR TO TSRA WITH A CHANCE FOR IFR DURING
AND JUST AFTER TSRA THROUGH MID-MORNING.
* 1-3 HOUR PERIOD OF SOUTHEAST WINDS POSSIBLY AROUND 10 KT LIKELY IN
THE WAKE OF MORNING STORMS.
* ANOTHER ROUND OF TSRA PROBABLE MONDAY AFTERNOON OR EVENING.
//DISCUSSION...UPDATED 06Z...
THE ORGANIZED AREA OF STORMS ACROSS WESTERN WI AND SOUTHEAST MN
AS OF 06Z WILL CONTINUE TO MOVE SOUTHEAST THROUGH DAYBREAK WITH
SCATTERED STORMS CONTINUE TO DEVELOP AHEAD OF THE AREA. THESE
STORMS ARE LIKELY TO FILL IN SOME PRIOR TO THE MAIN STORMS
ARRIVAL...THOUGH THAT FILL-IN MAY BE MORE OVER SOUTHERN WI. THE
ORGANIZED AREA OF STORMS IS LIKELY TO BRING TEMPORARY IFR
CONDITIONS WITH THE HEAVIEST RAIN...AS WELL AS A WIND SHIFT TO
NORTHWEST. IN THE WAKE OF THE STORMS...AS IS OFTEN SEEN IN THE
WAKE OF MCS MODE...THE WINDS WILL PROBABLY TURN EASTERLY OR
SOUTHEASTERLY DURING THE MID-MORNING. THIS MAY ONLY BE SHORT-
LIVED BUT COULD HAVE SPEEDS AROUND 10 KT.
THE CONTINUED MOIST AND VERY UNSTABLE ATMOSPHERE...ESPECIALLY
ALOFT...WILL PRESENT THE CHANCE OF STORMS AT ANY POINT TODAY AND
THE UPCOMING EVENING. THE TAFS CONTINUE TO REFLECT WHERE WE
BELIEVE THE MOST PROBABLE PERIOD IS FOR REDEVELOPING STORMS. THE
MORNING STORMS WILL INEVITABLY HAVE SOME EFFECT...POSSIBLY
DETERRING REFIRING OF ANY STORMS UNTIL LATE AFTERNOON OR EVEN
EVENING...OR POSSIBLY HAVING THEM RE-FIRE JUST WEST OF SOUTH OF
CHICAGOLAND AIRPORTS. SO THAT MAKES THE FORECAST CHALLENGING AND
DOES NOT ALLOW FOR ANYTHING MORE THAN A PROB30 REGARDING THE
SECOND ROUND...AT LEAST AT THIS TIME. ANY STORMS THAT DO REDEVELOP
IN THE AFTERNOON LIKELY WILL BE POTENT GIVEN A HIGH AMOUNT OF
INSTABILITY AND SUPPORTIVE SHEAR.
//ORD AND MDW CONFIDENCE...UPDATED 09Z...
* HIGH IN PERIOD OF TSRA AROUND DAYBREAK AND MEDIUM-HIGH IN WINDS
WITH STORMS. MEDIUM-HIGH IN TEMPORARY IFR CONDITIONS WITH STORMS.
* MEDIUM-HIGH IN PERIOD OF SOUTHEAST WINDS IN THE WAKE OF STORMS
BUT LOW IN SPEEDS AND SPECIFICALLY HOW LONG THE SHIFT WILL
LAST.
* LOW-MEDIUM IN CIGS AND VISBY THROUGH THE STORMS AND IN THEIR
WAKE.
* MEDIUM IN SECOND ROUND OF TSRA AT SOME POINT THIS AFTERNOON
AND/OR EVENING. LOW IN TIMING.
//OUTLOOK FOR ORD/MDW FOR 12Z TUESDAY-12Z SUNDAY...UPDATED 00Z...
TUESDAY...SLIGHT CHANCE SHRA/TSRA...OTHERWISE VFR.
WEDNESDAY AND THURSDAY...PRIMARILY VFR.
THURSDAY NIGHT AND FRIDAY...SHRA/TSRA POSSIBLE.
SATURDAY...VFR LIKELY.
MTF/IZZI
&&
.MARINE...
207 AM CDT
WITH LOW PRESSURE APPROACHING FROM THE WEST TODAY...WINDS WILL WANT
TO BE SOUTHERLY ACROSS LAKE MICHIGAN. THE EXCEPTION TO THIS WILL
BE THIS MORNING WHEN A STORM COMPLEX PASSES OVER CENTRAL AND
SOUTHERN PORTIONS OF THE LAKE. THESE STORMS WILL LIKELY
TEMPORARILY SHIFT WINDS WESTERLY AND POSSIBLY WITH BRIEF GUSTS IN
EXCESS OF 35 KNOTS. AS THE LOW PASSES OVER THE CENTRAL PART OF THE
LAKE NEAR MIDNIGHT...WINDS WILL TURN NORTH ACROSS THE NORTHERN
PART OF THE LAKE. DURING THE DAY TUESDAY THESE NORTHERLY WINDS
SHOULD ENVELOP THE LAKE WITH 20-25KT GUSTS PROBABLE. THIS WILL
LEAD TO BUILDING WAVES THROUGH TUESDAY AFTERNOON AND EVENING IN
THE ILLINOIS AND INDIANA NEARSHORES...THOUGH AT THIS TIME SMALL
CRAFT ADVISORY CRITERIA IS NOT FORECAST.
THE ONLY OTHER THING TO NOTE IS THAT THE FOG THREAT OVER THE LAKE
PER WEBCAMS AND OBSERVATIONS APPEARS TO BE LOW...WITH ANY FOG MORE
IN PATCHES AT PRESENT PER SATELLITE DERIVED PRODUCTS. THE WARMING
WATER TEMPERATURES IN JUST THE PAST WEEK AND A HALF HAVE LIKELY
HELPED TO MINIMIZE THAT CONCERN.
MTF
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...FLASH FLOOD WATCH...ILZ003-ILZ004-ILZ005-ILZ006-ILZ008-ILZ010-
ILZ011-ILZ012-ILZ013-ILZ014-ILZ019-ILZ020-ILZ021-ILZ022-
ILZ023-ILZ032-ILZ033-ILZ039 UNTIL 1 AM TUESDAY.
HEAT ADVISORY...ILZ010-ILZ019-ILZ021-ILZ023-ILZ032-ILZ033-
ILZ039...NOON MONDAY TO 7 PM MONDAY.
IN...FLASH FLOOD WATCH...INZ001-INZ002-INZ010-INZ011-INZ019 UNTIL 1
AM TUESDAY.
LM...NONE.
&&
$$
VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
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AREA FORECAST DISCUSSION...UPDATED
NWS CHICAGO/ROMEOVILLE IL
452 AM CDT MON JUL 13 2015
.MESOSCALE DISCUSSION...450 AM CDT
THE MCS OVER SOUTHERN WISCONSIN HAS SHOWN A STRENGTHENING TREND
OVER THE PAST 90 MINUTES OR SO AS IT CONTINUES TO MOVE SOUTHEAST.
IT APPEARS A SECOND MCV /AFTER THE FIRST NOW IN NORTHEAST WI/ HAS
DEVELOPED JUST NORTHWEST OF THE MILWAUKEE METRO AND IS A SIGN OF
SOME LONGEVITY OF THE CURRENT SEVERE WEATHER THREAT. THE OVERALL
COMPLEX CONTINUES TO MOVE SOUTHEAST...ALTHOUGH THE MOST INTENSE
CELLS/BOWS/INTERACTIONS HAVE MAINLY BEEN PROPAGATING EAST. THIS IS
LIKELY DUE TO THE BETTER ORIENTATION OF THE 0-1KM AND 0-3KM SHEAR
VECTORS AS INDICATED BY THE RAP MODEL. IN THESE AREAS...ISOLATED
DAMAGING WIND SPEEDS HAVE BEEN OBSERVED PER LSRS FROM WFO MKX. THE
LOW-LEVEL WIND SHEAR MAGNITUDE ON THE WFO MKX VAD PROFILE AND SPC
RAP ANALYSIS /25-30 KT IN 0-1KM DEPTH/ AS WELL AS INDICATIONS THAT
THE BOUNDARY LAYER IS MIXED AHEAD OF THE LINE...DO INDICATE THE
POSSIBILITY OF A BRIEF TORNADO AS WELL...AND HAVE SEEN TEMPORARY
RADAR SIGNATURES INDICATING ROTATION.
OVERALL EXPECT THE MCS TO PROPAGATE SOUTHEASTWARD THROUGH THE
FORECAST AREA...INCLUDING MOVING THROUGH THE CHICAGO METRO AREA
BETWEEN 6 AM AND 730 AM. WHILE THE SEVERE THREAT IS EXPECTED TO
BE ISOLATED TO SCATTERED WITHIN THE LINE...FAIRLY WIDESPREAD 40-45
MPH GUSTS ARE LIKELY ESPECIALLY NORTH OF I-80 THROUGH 6-7 A.M PER
UPSTREAM OBSERVATIONS.
MTF
&&
.SHORT TERM...
400 AM CDT
THROUGH WEDNESDAY NIGHT...
SEVERE & FLASH FLOOD THREAT TODAY/TONIGHT & HEAT/HUMIDITY TODAY...
EXTREMELY COMPLEX FORECAST THE REST OF TODAY INTO TONIGHT AND ONE
THAT INCLUDES THE POTENTIAL FOR HIGHER END SEVERE WEATHER OF ALL
HAZARDS. ALSO SOME OPPRESSIVE HEAT POSSIBLY IN THE MIX. THE DEVIL
IS IN THE DETAILS...AND MESOSCALE EVOLUTION TODAY WILL IMPACT
MAGNITUDE AND LOCATION OF SEVERE THREAT...AS WELL AS TEMPS AND
HEAT INDEX VALUES ATTAINED. EVEN WITH LOWER CONFIDENCE DUE TO
UNCERTAINTY IN CONVECTIVE EVOLUTION TODAY...WILL BE ISSUING A HEAT
ADVISORY FOR THE SOUTHWEST THIRD OF THE CWA.
THE BIG QUESTION IS WHAT HAPPENS BEYOND THE ONGOING MCS TO OUR
NORTH THAT WILL LIKELY AFFECT ALL IF NOT MOST OF THE CWA THIS
MORNING AND THEN COULD SHIFT SOUTHEAST OF THE CWA BY MID DAY. FOR
ADDITIONAL DETAILS ON MCS AND ASSOCIATED SEVERE/HEAVY RAIN
POTENTIAL...REFER TO MESOSCALE DISCUSSION. FOR HI-RES CONVECTIVE
ALLOWING GUIDANCE THAT ASSISTED IN NEAR TERM PORTION OF
FORECAST...REFERRED TO MORE CONSISTENT 4KM NAM AND ARW/NMM-EAST.
HAVE DISCOUNTED HRRR/RAP AND WILD RUN TO RUN VARIATION EXHIBITED.
CONCEPTUALLY...EXPECTATION FOR MCS AND ASSOCIATED SHORTWAVE/SPEED
MAX TO PROPAGATE SOUTHEAST WOULD PUT US IN A SUBSIDENT REGIME FROM
THE MID-LATE MORNING INTO THE EARLY AFTERNOON. THERE WILL BE
DISRUPTION OF WIND FIELD AND CANNOT RULE OUT A WAKE LOW...AS WELL
AS PERIOD OF ONSHORE FLOW SLOWING TEMPERATURE RISE ALONG
LAKESHORE. IF NO BACKBUILDING OF MCS OCCURS...REMNANT OUTFLOW
BOUNDARIES ARE STILL LIKELY TO BE LEFT BEHIND. BUT TIMING OF WAVE
SHOULD ALLOW FOR CLOUD COVER TO DISSIPATE AND IMPRESSIVE EML
SAMPLED BY 00Z RAOBS TO OUR SOUTH AND WEST WILL BE ABLE TO FULLY
ADVECT EASTWARD. CLEARING/SUBSIDENCE WILL ALSO ALLOW WARM FRONT
CURRENTLY STRETCHING FROM SOUTHERN MN TO WEST CENTRAL IL TO LIFT
NORTHEAST. LAST 2 RUNS OF NAM12 HAVE REDEVELOPED CONVECTION AROUND
MID-DAY OVER CENTRAL CWA AND THEN PROPAGATED IT SOUTHEAST...WHICH
SLOWS RECOVERY PROCESS...BUT HAVE ALSO LARGELY DISCOUNTED THIS
SOLUTION.
ASSUMING WARM FRONT DOES LIFT NORTHEAST AND BRING CWA INTO WARM
SECTOR...OBS WEST OF THE BOUNDARY ON SUNDAY GENERALLY FEATURED
HIGHS IN THE UPPER 80S TO LOWER 90S AND DEWPOINTS IN THE UPPER 70S
TO AROUND 80. EXTREMELY WET SEASON SO FAR IN SOUTHERN CWA AND
EVAPOTRANSPIRATION FROM LARGE/MATURE CORN CROP LEADS ME TO BELIEVE
THAT AT LEAST A FEW SPOTS IN OUR SOUTHWEST CWA WILL REACH THESE 80
DEGREE/NEAR 80 DEWPOINTS THIS AFTERNOON. COUPLED WITH HIGHS NEAR
90...THIS WILL ENABLE HEAT INDEX VALUES TO PEAK IN 105 TO 110
RANGE...AND THUS ISSUED HEAT ADVISORY FROM LEE COUNTY TO IROQUOIS
COUNTY AND WEST. THE REST OF THE CWA SHOULD SEE PEAK HEAT INDEX
VALUES IN THE 95 TO 105 RANGE...WHICH IS STILL QUITE UNCOMFORTABLE
AND NOT SOMETHING COMMONLY EXPERIENCED THIS SUMMER SO FAR.
TEMP/DEWPOINT/CLOUD COVER FORECAST WILL THEN DICTATE WHETHER
INSTABILITY CAN BE MAXIMIZED OVER THE AREA...AND IF IT
DOES...MLCAPE VALUES OF AT LEAST 4000-5000 J/KG ARE POSSIBLE
THANKS TO HIGH DEWPOINTS AND STEEP MIDLEVEL LAPSE RATES. VOLATILE
AIRMASS WILL ALSO BE TOPPED BY NOSE OF UPPER LEVEL JET MAX OF
60-80 KT AND ABOUT 50 KT OF MIDLEVEL FLOW...PROVIDING 45-50 KT OF
NORTHWEST 0-6KM LAYER SHEAR THIS AFTERNOON INTO THIS EVENING. AT
LEAST ISOLATED TSRA CANNOT BE RULED OUT IN POSSIBLE LULL
PERIOD...BUT IF WE DO GET IT...REINITIATION OF TSRA IS EXPECTED TO
OCCUR LATE AFTERNOON INTO EARLY EVENING JUST TO WEST OR NORTHWEST
OF CWA. SOUTHWEST SURFACE WINDS...WESTERLY 850 MB WINDS OF 25-35
KT AND NORTHWEST MIDLEVEL WINDS WILL PROVIDE PLENTY OF VEERING
WITH HEIGHT. LOCATION OF INITIATION IS IN QUESTION...BUT SUSPECT
THAT APPROACHING COLD FRONT TRAILING FROM SURFACE LOW TO
NORTH...ASCENT FROM UPPER WAVE OVER UPPER MIDWEST AND ALSO
ELONGATED VORT MAX INTO WEST CENTRAL IL WILL BE ENOUGH TO BREAK
ANY CAPPING. ORIENTATION OF NORTHWEST SHEAR VECTOR TO INITIATING
BOUNDARY SHOULD RESULT IN AT LEAST INITIAL DISCRETE SUPERCELL
STORM MODE. THIS ALSO ADDS UNCERTAINTY TO POPS AS COVERAGE COULD
VERY WELL BE SCATTERED AND EVEN STAY SCATTERED IF EVOLUTION INTO
MCS/QLCS DOES NOT OCCUR THIS EVENING.
EXTREME INSTABILITY AND MORE THAN SUFFICIENT SHEAR...INCLUDING AT
THE LOW LEVELS...ESPECIALLY NEAR ANY LEFTOVER BOUNDARIES...MEANS
THAT EXPLOSIVE DEVELOPMENT AND ALL SEVERE HAZARDS ARE POSSIBLE.
THIS INCLUDES THE POTENTIAL FOR HIGH END DAMAGING WINDS/ESPECIALLY
IF TRANSITION TO A SEVERE MCS/QLCS OCCURS. IN ADDITION...DISCRETE
DEVELOPMENT REMAINING DOMINANT WOULD FAVOR POTENTIAL FOR
TORNADOES...INCLUDING A STRONG TORNADO OR TWO...AND LARGE TO VERY
LARGE HAIL. STORM MOTION WOULD FAVOR SOUTHEAST MOVEMENT INTO THE
MID TO LATE EVENING. IF SHORT WAVE APPROACHING FROM IA THIS
AFTERNOON ENDS UP BEING FOCUS FOR MORE WIDESPREAD
DEVELOPMENT...THIS COULD KEEP HIGHER END SEVERE THREAT OUT OF FAR
NORTHERN AND NORTHEAST IL AND EXTREME NORTHWEST INDIANA...AS PER
CURRENT DEPICTION OF MODERATE AND ENHANCED RISK FROM CWA. ANY
INTENSE CONVECTION WILL BE IN AN EXTREMELY MOIST AIRMASS...SO
EXCESSIVE RAIN RATES AND FLASH FLOODING WOULD BE LIKELY...AS IT
WONT TAKE MUCH WHETHER OVER INUNDATED SOUTHERN CWA OR URBAN AREAS.
NO CHANGES TO GOING FLASH FLOOD WATCH FOR THIS REASON. THE BOTTOM
LINE TODAY INTO TONIGHT IS STAY WEATHER AWARE...HAVE A WAY TO
RECEIVE WARNINGS...AND ALSO HAVE A SEVERE WEATHER SAFETY PLAN IN
PLACE AHEAD OF TIME SHOULD YOU NEED TO ACT. THERE ARE CERTAINLY
SCENARIOS IN WHICH CONVECTIVE EVOLUTION CAN STILL MODULATE OR EVEN
LESSEN SEVERE THREAT TODAY...BUT GIVEN PATTERN RECOGNITION OF
EXTREME CAPE AND SUFFICIENT SHEAR...SUSPECT AT LEAST PARTS OF CWA
WILL EXPERIENCE SEVERE WEATHER LATER TODAY INTO THIS EVENING AFTER
WHATEVER OCCURS THIS MORNING.
TUESDAY THROUGH WEDNESDAY NIGHT...
TUESDAY COULD FEATURE AT LEAST SCATTERED TSRA DEVELOPMENT AS
SECONDARY COLD FRONT/TROUGH AXIS INTERACTS WITH A STILL WARM AND
MOIST AIR MASS. COOLER AND DRIER AIR LOOKS TO MAKE A BRIEF RETURN
ON WEDNESDAY.
RC
&&
.LONG TERM...
342 AM CDT
THURSDAY THROUGH SUNDAY...
THE EMPHASIS ON THE FORECAST WAS CERTAINLY ON THE SHORT TERM THIS
MORNING SO HAVE GONE HEAVILY WITH A WELL-VERIFYING WEIGHTED MODEL
BLEND FOR MOST OF LATE WEEK AND NEXT WEEKEND. WARM ADVECTION IS
EXPECTED TO RETURN ON THURSDAY WITH BUILDING HEIGHTS AS THE BELT OF
UPPER LEVEL WESTERLIES UNDULATES NORTH. WITH BUILDING THICKNESSES
AND LIKELY INCREASING TEMPERATURES AND MOISTURE LATE IN THE
WEEK...DAILY QPF AND OUTPUT CHANCES OF STORMS ARE PRESENTLY
PROVIDED BY GUIDANCE...ALTHOUGH A PERIOD OF A DAY OR TWO OF
CAPPING LOOKS POSSIBLE...MAINLY FRIDAY-SATURDAY. TEMPERATURES
POSSIBLY COULD REACH THE 90S WITH 850MB TEMPERATURES FORECAST BY
THE NAEFS TO BE IN THE TOP 15 PERCENTILE FOR JULY BY SATURDAY.
MTF
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 09Z...
* PERIOD OF EARLY MORNING TSRA WITH IFR VISIBILITY CENTERED AROUND
DAYBREAK.
* WINDS BRIEFLY TURNING NORTHWEST AND GUSTING IN EXCESS OF 30 KT
WITH THE STORMS...WITH ISOLATED GUSTS IN EXCESS OF 45 KT
POSSIBLE.
* MVFR CIGS DEVELOPING PRIOR TO TSRA WITH A CHANCE FOR IFR DURING
AND JUST AFTER TSRA THROUGH MID-MORNING.
* 1-3 HOUR PERIOD OF SOUTHEAST WINDS POSSIBLY AROUND 10 KT LIKELY IN
THE WAKE OF MORNING STORMS.
* ANOTHER ROUND OF TSRA PROBABLE MONDAY AFTERNOON OR EVENING.
//DISCUSSION...UPDATED 06Z...
THE ORGANIZED AREA OF STORMS ACROSS WESTERN WI AND SOUTHEAST MN
AS OF 06Z WILL CONTINUE TO MOVE SOUTHEAST THROUGH DAYBREAK WITH
SCATTERED STORMS CONTINUE TO DEVELOP AHEAD OF THE AREA. THESE
STORMS ARE LIKELY TO FILL IN SOME PRIOR TO THE MAIN STORMS
ARRIVAL...THOUGH THAT FILL-IN MAY BE MORE OVER SOUTHERN WI. THE
ORGANIZED AREA OF STORMS IS LIKELY TO BRING TEMPORARY IFR
CONDITIONS WITH THE HEAVIEST RAIN...AS WELL AS A WIND SHIFT TO
NORTHWEST. IN THE WAKE OF THE STORMS...AS IS OFTEN SEEN IN THE
WAKE OF MCS MODE...THE WINDS WILL PROBABLY TURN EASTERLY OR
SOUTHEASTERLY DURING THE MID-MORNING. THIS MAY ONLY BE SHORT-
LIVED BUT COULD HAVE SPEEDS AROUND 10 KT.
THE CONTINUED MOIST AND VERY UNSTABLE ATMOSPHERE...ESPECIALLY
ALOFT...WILL PRESENT THE CHANCE OF STORMS AT ANY POINT TODAY AND
THE UPCOMING EVENING. THE TAFS CONTINUE TO REFLECT WHERE WE
BELIEVE THE MOST PROBABLE PERIOD IS FOR REDEVELOPING STORMS. THE
MORNING STORMS WILL INEVITABLY HAVE SOME EFFECT...POSSIBLY
DETERRING REFIRING OF ANY STORMS UNTIL LATE AFTERNOON OR EVEN
EVENING...OR POSSIBLY HAVING THEM RE-FIRE JUST WEST OF SOUTH OF
CHICAGOLAND AIRPORTS. SO THAT MAKES THE FORECAST CHALLENGING AND
DOES NOT ALLOW FOR ANYTHING MORE THAN A PROB30 REGARDING THE
SECOND ROUND...AT LEAST AT THIS TIME. ANY STORMS THAT DO REDEVELOP
IN THE AFTERNOON LIKELY WILL BE POTENT GIVEN A HIGH AMOUNT OF
INSTABILITY AND SUPPORTIVE SHEAR.
//ORD AND MDW CONFIDENCE...UPDATED 09Z...
* HIGH IN PERIOD OF TSRA AROUND DAYBREAK AND MEDIUM-HIGH IN WINDS
WITH STORMS. MEDIUM-HIGH IN TEMPORARY IFR CONDITIONS WITH STORMS.
* MEDIUM-HIGH IN PERIOD OF SOUTHEAST WINDS IN THE WAKE OF STORMS
BUT LOW IN SPEEDS AND SPECIFICALLY HOW LONG THE SHIFT WILL
LAST.
* LOW-MEDIUM IN CIGS AND VISBY THROUGH THE STORMS AND IN THEIR
WAKE.
* MEDIUM IN SECOND ROUND OF TSRA AT SOME POINT THIS AFTERNOON
AND/OR EVENING. LOW IN TIMING.
//OUTLOOK FOR ORD/MDW FOR 12Z TUESDAY-12Z SUNDAY...UPDATED 00Z...
TUESDAY...SLIGHT CHANCE SHRA/TSRA...OTHERWISE VFR.
WEDNESDAY AND THURSDAY...PRIMARILY VFR.
THURSDAY NIGHT AND FRIDAY...SHRA/TSRA POSSIBLE.
SATURDAY...VFR LIKELY.
MTF/IZZI
&&
.MARINE...
207 AM CDT
WITH LOW PRESSURE APPROACHING FROM THE WEST TODAY...WINDS WILL WANT
TO BE SOUTHERLY ACROSS LAKE MICHIGAN. THE EXCEPTION TO THIS WILL
BE THIS MORNING WHEN A STORM COMPLEX PASSES OVER CENTRAL AND
SOUTHERN PORTIONS OF THE LAKE. THESE STORMS WILL LIKELY
TEMPORARILY SHIFT WINDS WESTERLY AND POSSIBLY WITH BRIEF GUSTS IN
EXCESS OF 35 KNOTS. AS THE LOW PASSES OVER THE CENTRAL PART OF THE
LAKE NEAR MIDNIGHT...WINDS WILL TURN NORTH ACROSS THE NORTHERN
PART OF THE LAKE. DURING THE DAY TUESDAY THESE NORTHERLY WINDS
SHOULD ENVELOP THE LAKE WITH 20-25KT GUSTS PROBABLE. THIS WILL
LEAD TO BUILDING WAVES THROUGH TUESDAY AFTERNOON AND EVENING IN
THE ILLINOIS AND INDIANA NEARSHORES...THOUGH AT THIS TIME SMALL
CRAFT ADVISORY CRITERIA IS NOT FORECAST.
THE ONLY OTHER THING TO NOTE IS THAT THE FOG THREAT OVER THE LAKE
PER WEBCAMS AND OBSERVATIONS APPEARS TO BE LOW...WITH ANY FOG MORE
IN PATCHES AT PRESENT PER SATELLITE DERIVED PRODUCTS. THE WARMING
WATER TEMPERATURES IN JUST THE PAST WEEK AND A HALF HAVE LIKELY
HELPED TO MINIMIZE THAT CONCERN.
MTF
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...FLASH FLOOD WATCH...ILZ003-ILZ004-ILZ005-ILZ006-ILZ008-ILZ010-
ILZ011-ILZ012-ILZ013-ILZ014-ILZ019-ILZ020-ILZ021-ILZ022-
ILZ023-ILZ032-ILZ033-ILZ039 UNTIL 1 AM TUESDAY.
HEAT ADVISORY...ILZ010-ILZ019-ILZ021-ILZ023-ILZ032-ILZ033-
ILZ039...NOON MONDAY TO 7 PM MONDAY.
IN...FLASH FLOOD WATCH...INZ001-INZ002-INZ010-INZ011-INZ019 UNTIL 1
AM TUESDAY.
LM...NONE.
&&
$$
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AREA FORECAST DISCUSSION
NWS DES MOINES IA
1132 PM CDT SUN JUL 12 2015
.SHORT TERM /TONIGHT/...
ISSUED AT 337 PM CDT SUN JUL 12 2015
MAIN ISSUE OVERNIGHT IS THE THREAT OF THUNDERSTORMS...SOME OF
WHICH COULD BE SEVERE.
FRONTAL BOUNDARY ALIGNS ROUGHLY WITH PERSISTENT STRATUS
FIELD...AND DEWPOINTS HAVE POOLED JUST UPSTREAM FROM THIS
BOUNDARY. CLOSEST ACTIVE CONVECTION IS STILL IN NORTHERN
MINNESOTA...BUT SHORT WAVE TROF IS APPROACHING SOUTH DAKOTA
MINNESOTA LINE AT THIS TIME AND SHOULD ENHANCE CONVECTIVE
COVERAGE. MOST CONVECTIVE ALLOWING MODELS KEEP MAIN MCS EAST OF
THIS FORECAST AREA BUT THE HRRR HAS BEEN INDICATING A POSSIBILITY
OF ISOLATED STORMS ALONG THE SOUTHWESTERN END OF THE ADVANCING
CONVECTION. IF THESE FORM IT WILL QUICKLY GO SEVERE WITH LARGE
HAIL AND WIND THE PRIMARY THREAT. MAIN MCS SHOULD MOVE PAST THE
AREA BY 12 UTC AND FRONT DOESN`T REALLY MOVE MUCH BY THEN.
.LONG TERM /MONDAY THROUGH SUNDAY/...
ISSUED AT 337 PM CDT SUN JUL 12 2015
HOT AND HUMID CONDITIONS CONTINUE ON MONDAY OVER THE SOUTHERN
HALF OF THE FORECAST AREA AND RAIN CHANCES WEDNESDAY NIGHT INTO
THURSDAY WERE THE MAIN ISSUES DURING THE EXTENDED PERIOD. LEANED
TOWARD A NAM12/ECMWF BLEND FOR TEMPS MONDAY INTO TUESDAY AND
CLOSER TO THE ECMWF/GFS THROUGH NEXT WEEKEND.
MONDAY AND TUESDAY...TWEAKED MAX TEMPS UP SLIGHTLY ALONG WITH DEW
POINTS OVER CENTRAL TO SOUTHEAST PORTIONS OF THE FORECAST AREA
AS THE COLD FRONT LOOKS TO BE A BIT SLOWER IN PROGRESSING ACROSS
THE STATE UNTIL LATER IN THE AFTERNOON. NOT A SIGNIFICANT AMOUNT
OF FORCING WITH THE FRONT...BUT ENOUGH THERE TO KEEP SLIGHT POPS
GOING IN THE AFTERNOON ACROSS THE EAST. SURFACE HIGH PRESSURE AND
UPPER LEVEL RIDGE HOLD IN PLACE ON TUESDAY WILL PROVIDE A MUCH
LESS HUMID AIR MASS OVER THE STATE. SOME MIXING LOOKS TO PUSH
TEMPS BACK INTO THE LOWER 90S OVER THE CENTRAL TO SOUTH
TUESDAY...BUT WITH LESS HUMIDITY NOT CONCERNED WITH EXTREME HEAT
INDEX VALUES.
WEDNESDAY INTO THURSDAY...LARGE UPPER LEVEL RIDGE PERSISTS ACROSS
THE CENTRAL U.S. THROUGH THE END OF THE WEEK. THE STRONGEST
SHORTWAVE AND BEST CONFIDENCE IN ANY PRECIPITATION DURING THE
EXTENDED IS WEDNESDAY NIGHT INTO THURSDAY. ECMWF AND GFS ARE IN
SOMEWHAT GOOD AGREEMENT WRT TO PRECIP CHANCES DURING THE
AFOREMENTIONED TIME FRAME. ANOTHER HEAVY RAIN EVENT LOOKS POSSIBLE
WITH WARM LAYER CLOUD DEPTHS AS HIGH AS 4000 METERS AND
PRECIPITABLE WATER NEAR 2 INCHES. LOWER CONFIDENCE WITH SEVERE
POTENTIAL WITH NO SIGNIFICANT AMOUNT OF INSTABILITY AND SHEAR
PRESENT.
FRIDAY THROUGH SUNDAY...TRENDED DRIER FRIDAY INTO SATURDAY AS
EXTENDED MODELS DO NOT HAVE A GOOD HANDLE OF TIMING AND LOCATION
OF WHEN AND IF ANY SHORTWAVE RIDING THE UPPER LEVEL RIDGE WILL
AFFECT THE FORECAST AREA. THUS...WENT WITH LESSER POPS LATE IN THE
PERIOD. PLUS WITH THE DRIER FORECAST...TRENDED WARMER FOR HIGHS
OVER THE WEEKEND AS THINKING LESS CLOUD COVER AND MODELS AT LEAST
HINTING ON STRONGER WAA.
&&
.AVIATION...13/06Z
ISSUED AT 1132 PM CDT SUN JUL 12 2015
MAINLY VFR CONDITIONS EXPECTED ACROSS TAF LOCATIONS BUT THERE WILL
BE PATCHY FOG AND ISOLD TSRA POSSIBLE INVOF KMCW AND KALO TAF SITES
BTWN 09Z AND 11Z.
&&
.DMX WATCHES/WARNINGS/ADVISORIES...
HEAT ADVISORY FROM NOON TO 7 PM CDT MONDAY FOR ADAIR-ADAMS-APPANOOSE-
AUDUBON-BOONE-CARROLL-CASS-CLARKE-CRAWFORD-DALLAS-DAVIS-DECATUR-
GREENE-GUTHRIE-JASPER-LUCAS-MADISON-MAHASKA-MARION-MARSHALL-MONROE-
POLK-POWESHIEK-RINGGOLD-STORY-TAMA-TAYLOR-UNION-WAPELLO-WARREN-WAYNE.
&&
$$
SHORT TERM...HARDING
LONG TERM...PODRAZIK
AVIATION...FAB
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
529 AM EDT MON JUL 13 2015
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 507 AM EDT MON JUL 13 2015
WV IMAGERY AND RAP ANALYSIS INDICATED A BORAD MID/UPPER LEVEL RIDGE
CENTERED OVER THE SRN PLAINS AND A TROUGH OVER SRN MANITOBA. AT THE
SFC...A FRONTAL BOUNDARY FROM SE NORTH DAKOTA THROUGH SE MN INTO NRN
IL. THE STRONGEST CONVECTION WITH A LARGE MCS THAT DEVELOPED OVER MN
HAS SLIDE SE INTO CNTRL/SRN WI ALONG AND NORTH OF THE FRONT AND
MUCAPE GRADIENT. SHOWERS AND EMBEDDED TSRA ASSOCIATED WITH THE
LEFTOVER MCV PERSISTED INTO WRN LAKE SUPERIOR AND WRN UPPER MI.
TODAY...RADR TRENDS AND SHORT RANGE HIGH RES MODELS SUGGEST THAT THE
SHRA/TSRA OVER WRN UPPER MI WILL CONTINUE TO GRADUALLY SLIDE TO THE
EAST EARLY THIS MORNING WHILE ALSO WEAKENING AS THE PCPN MOVES AWAY
FROM THE AREA OF GREATER INSTABILITY. HOWEVER...THE APPROACH OF A
WEAK SHRTWV IN ADVANCE OF THE MANITOBA TROUGH MAY RESULT IN
ADDITIONAL DEVELOPMENT BY LATE MORNING INTO THE EARLY AFTERNOON AS
DAYTIME HEATING INCREASES AND A WEAK SFC TROUGH MOVES THROUGH THAT
COULD ALSO INTERACT WITH LAKE BREEZE BOUNDARIES. OVERALL CONFIDENCE
IN PCPN TIMING/COVERAGE IS LOW GIVEN MODEL DIFFERENCES AND LINGERING
EFFECTS OF THE LARGE MCS. WITH FCST MLCAPE VALUES ONLY INTO THE 500-
1000 J/KG RANGE AND WEAK 0-6KM/0-1KM SHEAR MAINLY JUST BRIEF HEAVY
RAIN WOULD BE THE MAIN HAZARD.
TONIGHT...EXPECT THE MID LEVEL TROUGH INTO THE NRN LAKES TO
GRADUALLY SINK OFF TO THE SE. WITH THE LOSS OF DAYTIME INSTABILITY
AND ANY WEAK MID LEVEL FORCING WITH THE TROUGH...SHRA/TSRA WILL
DIMINISH FROM THE NW OVERNIGHT. THERE MAY BE SOME SHOWERS LATE INTO
THE NORTH AS THE COLD FRONT SLIDES INTO THE AREA.
.LONG TERM...(TUESDAY THROUGH SUNDAY)
ISSUED AT 529 AM EDT MON JUL 13 2015
OUR OFF AND ON SHOWER/TS ACTIVITY WILL BE DIMINISHING SIGNIFICANTLY
AFTER TUESDAY MORNING...AND MAY BE MORE LIMITED THROUGH THE REST OF
THE FCST PERIOD IF THE NEXT COUPLE OF SYSTEMS ARE UNABLE TO BREAK
DOWN THE STUBBORN 500MB RIDGE ACROSS MUCH OF THE CENTRAL U.S.
EXPECT SOME BRIEF GUSTY WINDS TUESDAY AS THE DEEPENING SFC LOW OVER
N LOWER MI AT 12Z SINKS ACROSS LAKE ERIE...AND LARGE HIGH PRESSURE
PUSHES IN FROM CENTRAL CANADA. THIS WILL BE WHILE THE 500MB LOW OVER
N QUEBEC AND TROUGH EXTENDING ACROSS LOWER MI EXIT TOO.
PW VALUES WILL FALL FROM AN AVG 1.5IN AT 12Z TUESDAY TO 0.3IN
TUESDAY NIGHT AS 850MB TEMPS FALL TO AROUND 11C /FROM NEAR 16C/.
MODEL GUIDANCE FOLLOWS THIS TREND PRETTY WELL...AND LOWERING THE
OVERNIGHT TEMPS EVEN MORE FOR TUESDAY NIGHT MAY BE NECESSARY BY
LATER SHIFTS. CURRENTLY EXPECT TEMPS TO BOTTOM OUT IN THE MID 40S TO
RIGHT AROUND 50F...WARMEST ALONG THE GREAT LAKES SHORELINES. LOOK
FOR SLOWLY INCREASING MOISTURE DURING THE DAY WEDNESDAY. THE SFC
HIGH WILL BE DIRECTLY OVER UPPER MI WEDNESDAY AFTERNOON...BEFORE
SLOWLY CENTERING ACROSS LAKE HURON AND THE LOWER GREAT LAKES
THURSDAY AFTERNOON...AND THE NEW ENGLAND STATES THURSDAY EVENING.
A LARGE AREA OF HIGH PRESSURE OVER S CENTRAL AND THE N TO CENTRAL
PLAINS STATES THURSDAY EVENING WILL BE PRESENT THROUGH THE WEEKEND.
THE 500MB RIDGE ACROSS MUCH OF THE E TWO-THIRDS OF THE NATION LOOKS
TO BECOME MORE ZONAL OVER THE UPPER GREAT LAKES FRIDAY MORNING. THE
RIDGE WILL REBOUND SATURDAY. THERE ARE SOME SIGNIFICANT DIFFERENCES
BETWEEN THE GFS AND ECMWF LATE SUNDAY AFTERNOON INTO MONDAY. A
GENERAL MODEL BLEND LOOKS TO BE BEST THAT FAR OUT...WITH 20-40
PERCENT POPS.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT)
ISSUED AT 124 AM EDT MON JUL 13 2015
SOME SHOWERS/EMBEDDED TS ON THE NRN FRINGE OF CONVECTIVE COMPLEX
MOVING THRU WI ARE LIKELY TO IMPACT IWD THE FIRST COUPLE HRS OF THE
FCST PERIOD...RESULTING IN SOME MVFR AND PERHAPS IFR CONDITIONS. THE
REMNANTS OF THESE SHOWERS MAY REACH CMX AND SAW AS WELL LATER...BUT
TS ARE NOT LIKELY ENUF AT THESE PLACES TO WARRANT A SPECIFIC MENTION
IN THE TAF. MVFR CONDITIONS ARE POSSIBLE AT THESE SITES AS WELL WITH
HUMID AIR AND NOCTURNAL COOLING...ESPECIALLY IF THE SHOWERS REACH
THESE AIRPORTS. MORE SHOWERS AND PERHAPS MVFR CONDITIONS MAY LINGER
THRU MUCH OF THE MRNG AS WELL ALONG WITH THE MVFR CONDITIONS. BUT IN
THE AFTN...DAYTIME HEATING IS LIKELY TO CAUSE A RETURN TO VFR WX.
THIS HEATING MAY ALSO CAUSE MORE SHOWERS AND PERHAPS A TS TO DEVELOP
AS WELL...ESPECIALLY AT IWD AND SAW AWAY FM LK SUP MODERATION. MVFR
CONDITIONS WL BE POSSIBLE AGAIN BY LATE EVNG WITH LINGERING LLVL
MSTR/NOCTURNAL COOLING.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 515 AM EDT MON JUL 13 2015
A WEAK TROUGH MOVING THROUGH THE NRN LAKES TODAY INTO THIS EVENING
WILL KEEP WINDS BELOW 20 KNOTS. A COLD FRONT WILL DROP SOUTH ACROSS
LAKE SUPERIOR LATE TONIGHT...SHIFTING THE WINDS TO A NORTHERLY
DIRECTION. WINDS MAY INCREASE TO AROUND 20 KNOTS LATE TONIGHT INTO
TUE MORNING BEHIND THE FRONT BUT SHOULD DIMINISH TUE AFTERNOON. A
HIGH PRESSURE RIDGE WILL THEN MOVE OVER LAKE SUPERIOR FOR TUESDAY
NIGHT THROUGH WEDNESDAY NIGHT AND KEEP WINDS LIGHT.
AREAS OF FOG WILL CONTINUE TO AFFECT LAKE SUPERIOR TODAY INTO
TONIGHT AS WINDS REMAIN RELATIVELY LIGHT AND ABUNDANT LOW LEVEL
MOISTURE REMAINS OVER THE REGION. SO...THE DENSE FOG ADVY REMAINS IN
EFFECT THROUGH TONIGHT. AS DRIER AIR AND STRONGER MIXING ARRIVE
LATER TUESDAY INTO TUESDAY NIGHT BEHIND THE COLD FRONT...EXPECT THE
FOG TO DISSIPATE.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
DENSE FOG ADVISORY UNTIL 8 AM EDT TUESDAY FOR LSZ263-264-266.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...JLB
LONG TERM...KF
AVIATION...KC
MARINE...JLB
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
516 AM EDT MON JUL 13 2015
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 507 AM EDT MON JUL 13 2015
WV IMAGERY AND RAP ANALYSIS INDICATED A BORAD MID/UPPER LEVEL RIDGE
CENTERED OVER THE SRN PLAINS AND A TROUGH OVER SRN MANITOBA. AT THE
SFC...A FRONTAL BOUNDARY FROM SE NORTH DAKOTA THROUGH SE MN INTO NRN
IL. THE STRONGEST CONVECTION WITH A LARGE MCS THAT DEVELOPED OVER MN
HAS SLIDE SE INTO CNTRL/SRN WI ALONG AND NORTH OF THE FRONT AND
MUCAPE GRADIENT. SHOWERS AND EMBEDDED TSRA ASSOCIATED WITH THE
LEFTOVER MCV PERSISTED INTO WRN LAKE SUPERIOR AND WRN UPPER MI.
TODAY...RADR TRENDS AND SHORT RANGE HIGH RES MODELS SUGGEST THAT THE
SHRA/TSRA OVER WRN UPPER MI WILL CONTINUE TO GRADUALLY SLIDE TO THE
EAST EARLY THIS MORNING WHILE ALSO WEAKENING AS THE PCPN MOVES AWAY
FROM THE AREA OF GREATER INSTABILITY. HOWEVER...THE APPROACH OF A
WEAK SHRTWV IN ADVANCE OF THE MANITOBA TROUGH MAY RESULT IN
ADDITIONAL DEVELOPMENT BY LATE MORNING INTO THE EARLY AFTERNOON AS
DAYTIME HEATING INCREASES AND A WEAK SFC TROUGH MOVES THROUGH THAT
COULD ALSO INTERACT WITH LAKE BREEZE BOUNDARIES. OVERALL CONFIDENCE
IN PCPN TIMING/COVERAGE IS LOW GIVEN MODEL DIFFERENCES AND LINGERING
EFFECTS OF THE LARGE MCS. WITH FCST MLCAPE VALUES ONLY INTO THE 500-
1000 J/KG RANGE AND WEAK 0-6KM/0-1KM SHEAR MAINLY JUST BRIEF HEAVY
RAIN WOULD BE THE MAIN HAZARD.
TONIGHT...EXPECT THE MID LEVEL TROUGH INTO THE NRN LAKES TO
GRADUALLY SINK OFF TO THE SE. WITH THE LOSS OF DAYTIME INSTABILITY
AND ANY WEAK MID LEVEL FORCING WITH THE TROUGH...SHRA/TSRA WILL
DIMINISH FROM THE NW OVERNIGHT. THERE MAY BE SOME SHOWERS LATE INTO
THE NORTH AS THE COLD FRONT SLIDES INTO THE AREA.
.LONG TERM...(MONDAY NIGHT THROUGH SUNDAY)
ISSUED AT 301 PM EDT SUN JUL 12 2015
NAM SHOWS A TROUGH ON THE WEST COAST...A RIDGE OVER THE
ROCKIES...SHORTWAVE OVER THE UPPER GREAT LAKES 00Z TUE. A COLD FRONT
MOVES THROUGH THE AREA MON NIGHT INTO TUE AND THEN WENT DRY FOR TUE
NIGHT AND WED. OVERALL...DID NOT MAKE TOO MANY CHANGES TO THE GOING
FORECAST FOR TEMPERATURES OR WEATHER.
IN THE EXTENDED...GFS AND ECMWF SHOW A BROAD 500 MB TROUGH IN THE
WESTERN U.S. AND A RIDGE ACROSS THE GULF COAST 12Z THU. THERE IS
ALSO A SHORTWAVE OVER THE NORTHERN PLAINS 12Z THU THAT MOVES INTO
THE UPPER GREAT LAKES 12Z FRI. BEHIND THIS SHORTWAVE...UPPER RIDGING
MOVES INTO THE UPPER GREAT LAKES ON SAT INTO SUN WITH SOME WARMER
AIR TRYING TO GET INTO THE AREA THIS NEXT WEEKEND. SFC FRONTS WILL
BE IN THE AREA WITH THE AREA BEING ON THE BOUNDARY BETWEEN VERY WARM
AND HUMID AIR TO THE SOUTH AND COOLER AND DRIER AIR TO THE NORTH AND
HAVING SOME POPS IN FOR THE EXTENDED SEEMS WARRANTED.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT)
ISSUED AT 124 AM EDT MON JUL 13 2015
SOME SHOWERS/EMBEDDED TS ON THE NRN FRINGE OF CONVECTIVE COMPLEX
MOVING THRU WI ARE LIKELY TO IMPACT IWD THE FIRST COUPLE HRS OF THE
FCST PERIOD...RESULTING IN SOME MVFR AND PERHAPS IFR CONDITIONS. THE
REMNANTS OF THESE SHOWERS MAY REACH CMX AND SAW AS WELL LATER...BUT
TS ARE NOT LIKELY ENUF AT THESE PLACES TO WARRANT A SPECIFIC MENTION
IN THE TAF. MVFR CONDITIONS ARE POSSIBLE AT THESE SITES AS WELL WITH
HUMID AIR AND NOCTURNAL COOLING...ESPECIALLY IF THE SHOWERS REACH
THESE AIRPORTS. MORE SHOWERS AND PERHAPS MVFR CONDITIONS MAY LINGER
THRU MUCH OF THE MRNG AS WELL ALONG WITH THE MVFR CONDITIONS. BUT IN
THE AFTN...DAYTIME HEATING IS LIKELY TO CAUSE A RETURN TO VFR WX.
THIS HEATING MAY ALSO CAUSE MORE SHOWERS AND PERHAPS A TS TO DEVELOP
AS WELL...ESPECIALLY AT IWD AND SAW AWAY FM LK SUP MODERATION. MVFR
CONDITIONS WL BE POSSIBLE AGAIN BY LATE EVNG WITH LINGERING LLVL
MSTR/NOCTURNAL COOLING.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 515 AM EDT MON JUL 13 2015
A WEAK TROUGH MOVING THROUGH THE NRN LAKES TODAY INTO THIS EVENING
WILL KEEP WINDS BELOW 20 KNOTS. A COLD FRONT WILL DROP SOUTH ACROSS
LAKE SUPERIOR LATE TONIGHT...SHIFTING THE WINDS TO A NORTHERLY
DIRECTION. WINDS MAY INCREASE TO AROUND 20 KNOTS LATE TONIGHT INTO
TUE MORNING BEHIND THE FRONT BUT SHOULD DIMINISH TUE AFTERNOON. A
HIGH PRESSURE RIDGE WILL THEN MOVE OVER LAKE SUPERIOR FOR TUESDAY
NIGHT THROUGH WEDNESDAY NIGHT AND KEEP WINDS LIGHT.
AREAS OF FOG WILL CONTINUE TO AFFECT LAKE SUPERIOR TODAY INTO
TONIGHT AS WINDS REMAIN RELATIVELY LIGHT AND ABUNDANT LOW LEVEL
MOISTURE REMAINS OVER THE REGION. SO...THE DENSE FOG ADVY REMAINS IN
EFFECT THROUGH TONIGHT. AS DRIER AIR AND STRONGER MIXING ARRIVE
LATER TUESDAY INTO TUESDAY NIGHT BEHIND THE COLD FRONT...EXPECT THE
FOG TO DISSIPATE.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
DENSE FOG ADVISORY UNTIL 8 AM EDT TUESDAY FOR LSZ263-264-266.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...JLB
LONG TERM...07
AVIATION...KC
MARINE...JLB
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
508 AM EDT MON JUL 13 2015
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 507 AM EDT MON JUL 13 2015
WV IMAGERY AND RAP ANALYSIS INDICATED A BORAD MID/UPPER LEVEL RIDGE
CENTERED OVER THE SRN PLAINS AND A TROUGH OVER SRN MANITOBA. AT THE
SFC...A FRONTAL BOUNDARY FROM SE NORTH DAKOTA THROUGH SE MN INTO NRN
IL. THE STRONGEST CONVECTION WITH A LARGE MCS THAT DEVELOPED OVER MN
HAS SLIDE SE INTO CNTRL/SRN WI ALONG AND NORTH OF THE FRONT AND
MUCAPE GRADIENT. SHOWERS AND EMBEDDED TSRA ASSOCIATED WITH THE
LEFTOVER MCV PERSISTED INTO WRN LAKE SUPERIOR AND WRN UPPER MI.
TODAY...RADR TRENDS AND SHORT RANGE HIGH RES MODELS SUGGEST THAT THE
SHRA/TSRA OVER WRN UPPER MI WILL CONTINUE TO GRADUALLY SLIDE TO THE
EAST EARLY THIS MORNING WHILE ALSO WEAKENING AS THE PCPN MOVES AWAY
FROM THE AREA OF GREATER INSTABILITY. HOWEVER...THE APPROACH OF A
WEAK SHRTWV IN ADVANCE OF THE MANITOBA TROUGH MAY RESULT IN
ADDITIONAL DEVELOPMENT BY LATE MORNING INTO THE EARLY AFTERNOON AS
DAYTIME HEATING INCREASES AND A WEAK SFC TROUGH MOVES THROUGH THAT
COULD ALSO INTERACT WITH LAKE BREEZE BOUNDARIES. OVERALL CONFIDENCE
IN PCPN TIMING/COVERAGE IS LOW GIVEN MODEL DIFFERENCES AND LINGERING
EFFECTS OF THE LARGE MCS. WITH FCST MLCAPE VALUES ONLY INTO THE 500-
1000 J/KG RANGE AND WEAK 0-6KM/0-1KM SHEAR MAINLY JUST BRIEF HEAVY
RAIN WOULD BE THE MAIN HAZARD.
TONIGHT...EXPECT THE MID LEVEL TROUGH INTO THE NRN LAKES TO
GRADUALLY SINK OFF TO THE SE. WITH THE LOSS OF DAYTIME INSTABILITY
AND ANY WEAK MID LEVEL FORCING WITH THE TROUGH...SHRA/TSRA WILL
DIMINISH FROM THE NW OVERNIGHT. THERE MAY BE SOME SHOWERS LATE INTO
THE NORTH AS THE COLD FRONT SLIDES INTO THE AREA.
.LONG TERM...(MONDAY NIGHT THROUGH SUNDAY)
ISSUED AT 301 PM EDT SUN JUL 12 2015
NAM SHOWS A TROUGH ON THE WEST COAST...A RIDGE OVER THE
ROCKIES...SHORTWAVE OVER THE UPPER GREAT LAKES 00Z TUE. A COLD FRONT
MOVES THROUGH THE AREA MON NIGHT INTO TUE AND THEN WENT DRY FOR TUE
NIGHT AND WED. OVERALL...DID NOT MAKE TOO MANY CHANGES TO THE GOING
FORECAST FOR TEMPERATURES OR WEATHER.
IN THE EXTENDED...GFS AND ECMWF SHOW A BROAD 500 MB TROUGH IN THE
WESTERN U.S. AND A RIDGE ACROSS THE GULF COAST 12Z THU. THERE IS
ALSO A SHORTWAVE OVER THE NORTHERN PLAINS 12Z THU THAT MOVES INTO
THE UPPER GREAT LAKES 12Z FRI. BEHIND THIS SHORTWAVE...UPPER RIDGING
MOVES INTO THE UPPER GREAT LAKES ON SAT INTO SUN WITH SOME WARMER
AIR TRYING TO GET INTO THE AREA THIS NEXT WEEKEND. SFC FRONTS WILL
BE IN THE AREA WITH THE AREA BEING ON THE BOUNDARY BETWEEN VERY WARM
AND HUMID AIR TO THE SOUTH AND COOLER AND DRIER AIR TO THE NORTH AND
HAVING SOME POPS IN FOR THE EXTENDED SEEMS WARRANTED.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT)
ISSUED AT 124 AM EDT MON JUL 13 2015
SOME SHOWERS/EMBEDDED TS ON THE NRN FRINGE OF CONVECTIVE COMPLEX
MOVING THRU WI ARE LIKELY TO IMPACT IWD THE FIRST COUPLE HRS OF THE
FCST PERIOD...RESULTING IN SOME MVFR AND PERHAPS IFR CONDITIONS. THE
REMNANTS OF THESE SHOWERS MAY REACH CMX AND SAW AS WELL LATER...BUT
TS ARE NOT LIKELY ENUF AT THESE PLACES TO WARRANT A SPECIFIC MENTION
IN THE TAF. MVFR CONDITIONS ARE POSSIBLE AT THESE SITES AS WELL WITH
HUMID AIR AND NOCTURNAL COOLING...ESPECIALLY IF THE SHOWERS REACH
THESE AIRPORTS. MORE SHOWERS AND PERHAPS MVFR CONDITIONS MAY LINGER
THRU MUCH OF THE MRNG AS WELL ALONG WITH THE MVFR CONDITIONS. BUT IN
THE AFTN...DAYTIME HEATING IS LIKELY TO CAUSE A RETURN TO VFR WX.
THIS HEATING MAY ALSO CAUSE MORE SHOWERS AND PERHAPS A TS TO DEVELOP
AS WELL...ESPECIALLY AT IWD AND SAW AWAY FM LK SUP MODERATION. MVFR
CONDITIONS WL BE POSSIBLE AGAIN BY LATE EVNG WITH LINGERING LLVL
MSTR/NOCTURNAL COOLING.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 351 PM EDT SUN JUL 12 2015
A WEAKENING RIDGE COMBINED WITH AN LOW PRESSURE SYSTEM MOVING FROM
SOUTHEAST SASKATCHEWAN THROUGH SOUTHERN WISCONSIN WILL KEEP WINDS
BELOW 20KTS THROUGH MONDAY EVENING. A COLD FRONT WILL DROP SOUTH
ACROSS LAKE SUPERIOR LATE MONDAY NIGHT...SHIFTING THE WINDS TO A
NORTHERLY DIRECTION...BUT SPEEDS WILL LARGELY STAY BELOW 20KTS. A
HIGH PRESSURE RIDGE WILL THEN MOVE OVER LAKE SUPERIOR FOR TUESDAY
NIGHT THROUGH WEDNESDAY NIGHT AND KEEP WINDS LIGHT.
AREAS OF FOG CONTINUE TO AFFECT LAKE SUPERIOR TODAY AS WARM...MOIST
AIR IS FLOWING OVER THE RELATIVELY COOL OPEN WATERS OF LAKE
SUPERIOR. THIS MORNING THE FOG WAS CONFINED TO THE NORTHERN HALF
OF THE LAKE...BUT LIGHT NORTHEASTERLY FLOW HAS EDGED THAT FOG A
LITTLE FARTHER TO THE SOUTH. SEVERAL SHIP OBS TODAY INDICATED THE
FOG WAS DENSE AT TIMES...SO DECIDED TO ISSUE A MARINE DENSE FOG
ADVISORY FOR THE NORTHERN PORTIONS OF LAKE SUPERIOR INTO MONDAY
NIGHT. WITH THE CONTINUED WARM AND MOIST AIR...ALONG WITH
SOME RAIN TONIGHT INTO MONDAY...WILL CONTINUE TO SHOW AREAS OF FOG
THROUGH MONDAY NIGHT. THEN AS DRIER AIR ARRIVES LATER TUESDAY INTO
TUESDAY NIGHT BEHIND THE COLD FRONT...EXPECT THE FOG POTENTIAL TO
DIMINISH.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
DENSE FOG ADVISORY UNTIL 8 AM EDT TUESDAY FOR LSZ263-264-266.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...JLB
LONG TERM...07
AVIATION...KC
MARINE...SRF
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
125 AM EDT MON JUL 13 2015
.SHORT TERM...(THIS EVENING THROUGH MONDAY)
ISSUED AT 351 PM EDT SUN JUL 12 2015
THE UPPER RIDGE THAT HAS BEEN OVER THE UPPER GREAT LAKES REGION WILL
BREAK DOWN THROUGH THE SHORT TERM PERIOD...SETTING THE STAGE TO A
RETURN TO BELOW NORMAL TEMPERATURES FOR THE TUESDAY-THURSDAY TIME
FRAME. THIS BREAKDOWN WILL BE DRIVEN BY THE SEVERAL EMBEDDED WAVES
ASSOCIATED WITH THE UPPER TROUGH OVER SOUTHERN ALBERTA/SASKATCHEWAN
AND MONTANA. A BROAD 1000MB SURFACE LOW IS LOCATED BELOW THIS UPPER
LOW AND A TROUGH STRETCHES SOUTHEAST INTO THE EASTERN DAKOTAS. THESE
FEATURES WILL BE THE MAIN FOCUS FOR CONVECTION LATE THIS AFTERNOON
INTO MONDAY. TO THE EAST OF THOSE FEATURES AND OVER UPPER
MICHIGAN...A HIGH PRESSURE RIDGE HAS BEEN WEAKENING AND DEPARTING
THE AREA TO THE SOUTHEAST. SOUTHERLY FLOW AROUND THIS HIGH CONTINUES
TO LEAD TO THE WARM/HUMID CONDITIONS ACROSS THE U.P....WITH
AFTERNOON TEMPERATURES IN THE LOWER 80S AND DEWPOINTS IN THE UPPER
50S AND LOWER 60S. WITH SUNSHINE TO START THE DAY...DIURNAL HEATING
HAS PRODUCED A CU FIELD OVER THE INTERIOR WEST...WHILE THE LAKE
BREEZE OVER THE EAST OFF LAKE MICHIGAN (KISQ ONLY 72 AT 3PM) HAS
STABILIZED THAT AREA AND KEEP CONDITIONS MOSTLY SUNNY. THUNDERSTORMS
HAVE CONTINUED TO DEVELOP IN THE NORTHEAST EDGE OF THE 850MB WARM
AIR ADVECTION IN NORTHEAST MINNESOTA AND NORTHWEST WISCONSIN...WHICH
IS NOW PUSHING SHOWERS AND THUNDERSTORMS EAST ACROSS WESTERN LAKE
SUPERIOR. THE TREND HAS BEEN FOR THEM TO DIMINISH AS THEY PUSH EAST
INTO THE WEAKER MID LEVEL LAPSE RATES AND AWAY FROM THE BETTER
FORCING. EXPECT THAT TO ALSO OCCUR WITH THE STORMS IN WESTERN LAKE
SUPERIOR AND HAVE SEEN A DOWNWARD TREND ON RADAR AND LIGHTNING OVER
THE LAST 15-30MIN. HAVE SEEN A FEW BRIEF SHOWERS DEVELOP OVER
WESTERN/CENTRAL UPPER MICHIGAN THIS AFTERNOON...BUT OVERALL THEY
HAVE BEEN FAIRLY SMALL AND VERY ISOLATED. EXPECT THAT ISOLATED
POTENTIAL TO CONTINUE...INHIBITED BY THE WEAKER MID LEVEL LAPSE
RATES AND RAP SOUNDINGS SHOWING SOME CAPPING NEAR 725MB. IF
SOMETHING COULD GET GOING WOULD LARGELY EXPECT BRIEF HEAVY RAIN AND
SMALL HAIL DUE TO THE HIGH FREEZING LEVELS. ANY OF THESE SHOWERS
THAT DO DEVELOP SHOULD DIMINISH AS DIURNAL HEATING IS LOST.
THE FORECAST THEN TURNS TO WHAT WILL OCCUR UPSTREAM IN EASTERN NORTH
DAKOTA AND NORTHWEST MINNESOTA OVER THE NEXT FEW HOURS.
THUNDERSTORMS WILL QUICKLY DEVELOP IN THAT AREA THIS EVENING
(ALREADY STARTING TO SEE DEVELOPMENT SOUTH AND EAST OF FARGO ALONG
THE WARM FRONT) IN ASSOCIATION WITH A SHORTWAVE NOW MOVING THROUGH
CENTRAL NORTH DAKOTA. WHILE THEY WILL BE DISCRETE STORMS
INITIALLY...THE EXPECTATION IS FOR THEM TO DEVELOP SOUTHEAST INTO AN
MCS THROUGH THE NIGHT. AT THIS POINT...THE EXPECTED DEVELOPMENT
LOCATION AND STORM MOTION WOULD MOVE THE STORMS TO THE EAST ACROSS
THE NORTHERN/CENTRAL PORTIONS OF MINNESOTA AND THEN DIVE FARTHER TO
THE SOUTHEAST AS THEY NEAR WESTERN WISCONSIN DUE TO THE SOUTHEAST
POINTING FORWARD PROPAGATING CORFIDI VECTORS AND THE LOCATION OF THE
MUCAPE GRADIENT. WHILE THE STRONGEST STORMS SHOULD STAY TO THE SOUTH
OF THE CWA...STILL THINK THE AREA WILL SEE THE NORTHERN SIDE OF THE
COMPLEX...WHICH WILL PRODUCE SHOWERS AND THUNDERSTORMS (ESPECIALLY
NEAR THE WISCONSIN BORDER OUT WEST). WILL CONTINUE TO SHOW THE
HIGHEST POPS THERE DURING THE OVERNIGHT HOURS AND THEN DIMINISH THEM
AS THE MAIN COMPLEX SLIDES AWAY FROM THE AREA. WILL ADD A MENTION OF
STRONG STORMS PRODUCING GUSTY WINDS FOR THE NORTHERN EDGE OF THE MCS
BRUSHING THE WISCONSIN BORDER.
THE QUESTION THEN TURNS TO WHAT WILL HAPPEN TOMORROW BEHIND THE MCS
THAT MOVES TO THE SOUTH OF THE AREA. THERE STILL WILL BE UPPER LEVEL
SUPPORT FOR SHOWERS/THUNDERSTORMS AS THE UPPER TROUGH ENERGY MOVES
THROUGH THE REGION (ALONG WITH THE SURFACE TROUGH). WILL CONTINUE TO
SHOW CHANCE POPS...LIKELY TIED TO THE COMBINATION OF THE UPPER
TROUGH AND WHAT IS LEFT OVER FROM THE NORTHERN EDGE OF THE MCS. THE
POPS WILL NEED TO BE FINE TUNED TONIGHT ONCE THE MCS HAS SHOWN ITS
LOCATION/MOVEMENT...AS IT WILL LIKELY AFFECT THE LOCATION OF THE
PRECIPITATION TOMORROW. INSTABILITY WILL NOT BE AS STRONG AS
TODAY...MUCAPE VALUES GENERALLY STRUGGLING TO EVEN GET TO 750J/KG
(EXCEPT OVER FAR WESTERN UPPER MICHIGAN)...SO THINK THE THUNDER
CHANCES WILL BE LIMITED BUT STILL KEEP THE CHANCE THERE.
.LONG TERM...(MONDAY NIGHT THROUGH SUNDAY)
ISSUED AT 301 PM EDT SUN JUL 12 2015
NAM SHOWS A TROUGH ON THE WEST COAST...A RIDGE OVER THE
ROCKIES...SHORTWAVE OVER THE UPPER GREAT LAKES 00Z TUE. A COLD FRONT
MOVES THROUGH THE AREA MON NIGHT INTO TUE AND THEN WENT DRY FOR TUE
NIGHT AND WED. OVERALL...DID NOT MAKE TOO MANY CHANGES TO THE GOING
FORECAST FOR TEMPERATURES OR WEATHER.
IN THE EXTENDED...GFS AND ECMWF SHOW A BROAD 500 MB TROUGH IN THE
WESTERN U.S. AND A RIDGE ACROSS THE GULF COAST 12Z THU. THERE IS
ALSO A SHORTWAVE OVER THE NORTHERN PLAINS 12Z THU THAT MOVES INTO
THE UPPER GREAT LAKES 12Z FRI. BEHIND THIS SHORTWAVE...UPPER RIDGING
MOVES INTO THE UPPER GREAT LAKES ON SAT INTO SUN WITH SOME WARMER
AIR TRYING TO GET INTO THE AREA THIS NEXT WEEKEND. SFC FRONTS WILL
BE IN THE AREA WITH THE AREA BEING ON THE BOUNDARY BETWEEN VERY WARM
AND HUMID AIR TO THE SOUTH AND COOLER AND DRIER AIR TO THE NORTH AND
HAVING SOME POPS IN FOR THE EXTENDED SEEMS WARRANTED.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT)
ISSUED AT 124 AM EDT MON JUL 13 2015
SOME SHOWERS/EMBEDDED TS ON THE NRN FRINGE OF CONVECTIVE COMPLEX
MOVING THRU WI ARE LIKELY TO IMPACT IWD THE FIRST COUPLE HRS OF THE
FCST PERIOD...RESULTING IN SOME MVFR AND PERHAPS IFR CONDITIONS. THE
REMNANTS OF THESE SHOWERS MAY REACH CMX AND SAW AS WELL LATER...BUT
TS ARE NOT LIKELY ENUF AT THESE PLACES TO WARRANT A SPECIFIC MENTION
IN THE TAF. MVFR CONDITIONS ARE POSSIBLE AT THESE SITES AS WELL WITH
HUMID AIR AND NOCTURNAL COOLING...ESPECIALLY IF THE SHOWERS REACH
THESE AIRPORTS. MORE SHOWERS AND PERHAPS MVFR CONDITIONS MAY LINGER
THRU MUCH OF THE MRNG AS WELL ALONG WITH THE MVFR CONDITIONS. BUT IN
THE AFTN...DAYTIME HEATING IS LIKELY TO CAUSE A RETURN TO VFR WX.
THIS HEATING MAY ALSO CAUSE MORE SHOWERS AND PERHAPS A TS TO DEVELOP
AS WELL...ESPECIALLY AT IWD AND SAW AWAY FM LK SUP MODERATION. MVFR
CONDITIONS WL BE POSSIBLE AGAIN BY LATE EVNG WITH LINGERING LLVL
MSTR/NOCTURNAL COOLING.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 351 PM EDT SUN JUL 12 2015
A WEAKENING RIDGE COMBINED WITH AN LOW PRESSURE SYSTEM MOVING FROM
SOUTHEAST SASKATCHEWAN THROUGH SOUTHERN WISCONSIN WILL KEEP WINDS
BELOW 20KTS THROUGH MONDAY EVENING. A COLD FRONT WILL DROP SOUTH
ACROSS LAKE SUPERIOR LATE MONDAY NIGHT...SHIFTING THE WINDS TO A
NORTHERLY DIRECTION...BUT SPEEDS WILL LARGELY STAY BELOW 20KTS. A
HIGH PRESSURE RIDGE WILL THEN MOVE OVER LAKE SUPERIOR FOR TUESDAY
NIGHT THROUGH WEDNESDAY NIGHT AND KEEP WINDS LIGHT.
AREAS OF FOG CONTINUE TO AFFECT LAKE SUPERIOR TODAY AS WARM...MOIST
AIR IS FLOWING OVER THE RELATIVELY COOL OPEN WATERS OF LAKE
SUPERIOR. THIS MORNING THE FOG WAS CONFINED TO THE NORTHERN HALF
OF THE LAKE...BUT LIGHT NORTHEASTERLY FLOW HAS EDGED THAT FOG A
LITTLE FARTHER TO THE SOUTH. SEVERAL SHIP OBS TODAY INDICATED THE
FOG WAS DENSE AT TIMES...SO DECIDED TO ISSUE A MARINE DENSE FOG
ADVISORY FOR THE NORTHERN PORTIONS OF LAKE SUPERIOR INTO MONDAY
NIGHT. WITH THE CONTINUED WARM AND MOIST AIR...ALONG WITH
SOME RAIN TONIGHT INTO MONDAY...WILL CONTINUE TO SHOW AREAS OF FOG
THROUGH MONDAY NIGHT. THEN AS DRIER AIR ARRIVES LATER TUESDAY INTO
TUESDAY NIGHT BEHIND THE COLD FRONT...EXPECT THE FOG POTENTIAL TO
DIMINISH.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
DENSE FOG ADVISORY UNTIL 8 AM EDT TUESDAY FOR LSZ263-264-266.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...SRF
LONG TERM...07
AVIATION...KC
MARINE...SRF
AREA FORECAST DISCUSSION...UPDATED
NWS DULUTH MN
1239 AM CDT MON JUL 13 2015
.UPDATE...
ISSUED AT 1239 AM CDT MON JUL 13 2015
UPDATED FOR THE NEW 06Z AVIATION DISCUSSION BELOW.
UPDATE ISSUED AT 555 PM CDT SUN JUL 12 2015
UPDATED TO ADD TORNADO WATCH. LOW LEVEL SHEAR HAS BEEN INCREASING
IN THE WATCH AREA. HAVE BEEN WATCHING TORNADIC STORMS TO THE WEST
AND EXPECT THIS SYSTEM TO EVENTUALLY SPREAD INTO EACH AREA IN THE
NEXT HOUR OR SO AS DESTABILIZATION INCREASES. LOOKS LIKE EARLIER
CIN IS GONE...SO WILL SEE A RAPID INCREASE IN STORM STREGTH. GOOD-
LOOKING HODOGRAPH FOR BRAINERD SUGGEST STRONG POTENTIAL FOR
ROTATING STORMS WITH LARGE HAIL DAMAGING WINDS AND TORNADOES.
&&
.SHORT TERM...(THIS EVENING THROUGH MONDAY)
ISSUED AT 333 PM CDT SUN JUL 12 2015
THE FORECAST AREA WAS BETWEEN DEPARTING HIGH PRESSURE OVER NORTHERN
LAKE SUPERIOR AND LOW PRESSURE MOVING THROUGH SE ND. A WARM FRONT
EXTENDED SEWD FROM THE LOW THROUGH WEST CENTRAL AND SW MN. THE LAST
REMNANTS OF THE MORNING THUNDERSTORMS WAS OVER THE TIP OF THE
ARROWHEAD AND SHOULD EXIT BY 21Z. NEW SHOWERS AND STORMS WERE
DEVELOPING IN WEST CENTRAL MN N OF THE WARM FRONT AND A COUPLE
COUNTIES W OF THE AREA. SOME OF THE CLOUDS HAVE DISSIPATED ALLOWING
FOR SOME WARMING AND AN INCREASE IN DEWPOINTS AS WELL AS AN INCREASE
IN INSTABILITY. EXPECT THUNDERSTORMS TO FORM ALONG AND N OF THE WARM
FRONT THROUGH THE REST OF THE AFTERNOON AND GRADUALLY SPREAD INTO
THE WESTERN PORTION OF THE REGION.
EXPECT SOME OF THE STORMS TO BECOME SEVERE TONIGHT AND PERCOLATE IN
THE VCNTY OF THE FORECAST AREA UNTIL 06Z. LATEST HRRR IS IN
AGREEMENT WITH THIS ASSESSMENT. SOME STORMS WILL STILL BE AROUND
THROUGH THE OVERNIGHT WITH HEAVY RAIN ACCOMPANYING SOME OF THE
STRONGER STORMS. HAVE SHOWN A GRADUAL DECREASE IN POPS AFTER 08Z
THROUGH 12Z AS HIGH PRESSURE BEGINS TO BUILD INTO THE AREA. EVEN
THOUGH SOME NICE RAIN WAS NOTED DURING THE DAY...NOT EXPECTING ANY
FLOODING ISSUES WITH THE STORMS TONIGHT.
ON MONDAY...THE SFC LOW MOVES ACROSS CENTRAL MN INTO NORTHERN WI.
SOME AREAS WILL GET A BREAK FROM THE STORMS IN THE MORNING BEFORE
REDEVELOPMENT BEGINS BY AFTERNOON. SOME OF THE STORMS MAY CONTAIN
BRIEF MODERATE DOWNPOURS. THE MAJORITY OF THE RAIN WILL FALL ALONG
AND N OF THE LOW TRACK WHERE AN UPPER LEVEL SHORT WAVE WILL TRACK
THROUGH THE AREA AS WELL.
.LONG TERM...(MONDAY NIGHT THROUGH SUNDAY)
ISSUED AT 333 PM CDT SUN JUL 12 2015
ACTIVE WEATHER PATTERN STILL LOOKS LIKELY WITH CHANCES FOR SHOWERS
AND STORMS MOST DAYS THIS WEEK. TEMPERATURES WILL BRIEFLY COOL DOWN
TO MORE SEASONABLE TEMPS MID-WEEK...RETURNING TO THE UNSEASONABLY
WARM AND HUMID WEATHER BY THE WEEKEND.
ON THE SYNOPTIC SCALE THE INFLUENCE OF THE 500MB RIDGE/UPPER HIGH
OVER THE SOUTHERN PLAINS WILL GIVE WAY TO A SERIES OF MID-LEVEL
DISTURBANCES THAT WILL MOVE ACROSS THE NORTHERN TIER OF THE COUNTRY.
A DEEP LONGWAVE TROUGH OVER THE WEST COAST WILL BEGIN TO FLATTEN OUT
AND CAUSE A SERIES OF MID-LEVEL SHORTWAVES TO MOVE EAST OVER THE
RIDGE. ON MONDAY NIGHT INTO TUESDAY A DEPARTING SFC LOW WILL GIVE
WAY TO A COLD FRONT MOVING IN FROM THE NORTH ON LATE TUESDAY. THIS
FRONTAL PASSAGE WILL RESULT IN NORTH TO NORTHEASTERLY WINDS AT LOW
LEVELS AND THUS COOLER TEMPS. THE COMBINATION OF THE ORIGIN OF THIS
AIR /CANADA/ AND THE FACT THAT MOST OF IT IS MOVING OVER LAKE
SUPERIOR BEFORE REACHING LAND WILL RESULT IN MUCH COOLER AND DRIER
/LOWER DEW POINT/ AIR. HOWEVER...WITH A RIDGE AXIS ALOFT MOVING
ACROSS THE AREA EARLY WEDNESDAY SOUTHWESTERLY FLOW WILL RETURN
RESULTING IN RISING TEMPS AND DEW POINT VALUES.
LATE IN THE WEEK WE HAVE FAIRLY HIGH PRECIP CHANCES...THOUGH THE
EXACT DETAILS OF EACH DAY ARE STILL TOUGH TO PIN DOWN.
REGARDLESS...OVERALL PATTERN IS FAVORABLE FOR SHOWERS AND STORMS
EACH DAY. LATE IN THE WEEK INTO THE WEEKEND GUIDANCE IS DEPICTING
MUCH STRONGER WINDS ALOFT WITH A 120KT OR SO JET AT 250MB. THESE
STRONGER WINDS ALOFT COULD LEAD TO A BETTER ENVIRONMENT THUNDERSTORM
DEVELOPMENT...DEPENDING ON HOW MUCH INSTABILITY CAN DEVELOP. WILL
DEFINITELY BE SOMETHING TO WATCH AS IT HAS BEEN A WHILE SINCE WE
HAVE HAD STRONGER WINDS ALOFT.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT)
ISSUED AT 1239 AM CDT MON JUL 13 2015
A POTENT COMPLEX OF THUNDERSTORMS WAS CONTINUING TO MOVE THROUGH
MINNESOTA AND WISCONSIN EARLY THIS MORNING. THE STRONGEST STORMS
HAD EXITED NE MINNESOTA AND NW WISCONSIN BY THE TIME OF WRITING
THIS DISCUSSION. THE KHYR/KDLH/KHIB CAN EXPECT RAIN AND OCCASIONAL
LIGHTNING THROUGH THE WEE HOURS OF THIS MORNING.
FOG AND LOW STRATUS COULD FORM EARLY THIS MORNING...AND POSSIBLY
BRING PERIODS OF LIFR/IFR CONDITIONS. THE FOG SHOULD DISSIPATE BY
8 AM.
SCATTERED SHOWERS AND THUNDERSTORMS WILL LIKELY DEVELOP LATE THIS
AFTERNOON AND THIS EVENING. THE SHOWERS AND STORMS WILL BECOME
LESS WIDESPREAD LATER TONIGHT...BUT COULD CONTINUE OVERNIGHT AS A
COLD FRONT DROPS OUT OF CANADA AND MOVES THROUGH NE MINNESOTA AND
THEN NW WISCONSIN.
THE ASOS AT KBRD HAS BEEN MALFUNCTIONING SINCE POWERFUL
THUNDERSTORMS ROLLED THROUGH THE AREA THIS PAST EVENING...AND HAS
NOT BEEN RELIABLY REPORTING WIND/VISIBILITY/CEILING INFORMATION.
AMENDMENTS ARE NOT SCHEDULED UNTIL THE ASOS CAN BE REPAIRED.
TECHNICIANS WILL BE NOTIFIED LATER THIS MORNING.
&&
.PRELIMINARY POINT TEMPS/POPS...
DLH 64 71 55 73 / 30 40 10 20
INL 62 78 56 79 / 30 40 30 20
BRD 64 82 59 83 / 40 50 10 20
HYR 63 76 56 79 / 30 30 10 20
ASX 60 69 53 75 / 30 40 10 20
&&
.DLH WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
LS...NONE.
&&
$$
UPDATE...GROCHOCINSKI
SHORT TERM...GSF
LONG TERM...JJM
AVIATION...GRANING/GROCHOCINSKI
AREA FORECAST DISCUSSION
NWS ST LOUIS MO
352 AM CDT MON JUL 13 2015
.SHORT TERM: (TODAY AND TONIGHT)
ISSUED AT 330 AM CDT MON JUL 13 2015
THE MAIN FORECAST ISSUES REMAIN HEAT AND THUNDERSTORM POTENTIAL
AND THE CAVEATS DISCUSSED THE LAST FEW DAYS HAVEN`T CHANGED. ALL
INDICATIONS SUGGEST THAT TODAY WE WILL SEE THE HOTTEST DAY THUS
FAR THIS SUMMER. SOUTHWESTERLY LOWER TROP FLOW, CONTINUED LOW-MID
LEVEL WARMING, GOOD SUNSHINE, AND A WARM START ALL POINT TO HIGH
TEMPERATURES IN THE 90S WITH THE HOTEST READINGS IN THE UPPER 90S
IN METRO ST. LOUIS. AFTERNOON HEAT INDICES WILL BE IN DANGEROUS
LEVELS OF 105+ AND I HAVE EXPANDED THE HEAT ADVISORY TO INCLUDED
THE ENTIRE CWA.
WE CONTINUE TO WRESTLE WITH THUNDERSTORM CHANCES TODAY. ALL OF THE
DETERMINISTIC MODELS SHOW SIGNIFICANT MID LEVEL WARMING WITH H7
TEMPS AOA +12 DEGC BY LATE AFTERNOON. THE DETERMINISTIC MODELS
ALSO HAVE LITTLE IF ANY QPF AND WHERE THEY DO IS ON THE FRINGES OF
THE CWA. ALTERNATIVELY A NUMBER OF THE CONVECTION ALLOWING MODELS
BRING THE NORTHWEST FLOW CONVECTIVE COMPLEXES ACROSS ILLINOIS AND
THEN HAVE OUTFLOW GENERATED CONVECTION WELL INTO EASTERN MO THIS
AFTERNOON. MY BEST FEELING IS THAT THE WESTERN EDGE OF THE MCS
NOW CENTERED IN WISCONSIN OR ITS REMNANT BOUNDARY HAS POTENTIAL TO
BRING THUNDERSTORMS TO THE FAR EASTERN CWA/SOUTH CENTRAL IL WHERE
I HAVE CHANCE POPS - AND IF THESE DO IN FACT OCCUR THEY COULD BE
SEVERE. I HAVE ADDED SOME SLIGHT CHANCE POPS INTO THE FORECAST
FURTHER TO THE WEST INTO MO TO ACCOUNT FOR AT LEAST SOME UNCERTAINTY
AND ALSO TO MESH WITH MY WESTERN NWS NEIGHBORS, HOWEVER CONFIDENCE
IS QUITE LOW GIVEN THE CAP STRENGTH THIS AFTERNOON.
I THINK OUR BEST POTENTIAL TO SEE STORMS WILL BE THIS EVENING
AHEAD OF THE COLD FRONT THAT WILL BE PUSHING INTO THE AREA FROM
IOWA. HEIGHT FALLS/COOLING ALOFT ASSOCIATED WITH NORTHWEST FLOW
IMPULSES APPEAR TO BE SUFFICIENT TO WEAKEN THE CAP AND ALLOW
SCATTERED THUNDERSTORMS TO DEVELOP ACROSS NORTHERN MO THIS
EVENING, TRACKING SOUTHEAST AND ALSO MOVING SOUTHWARD WITH THE
BOUNDARY. GIVEN THE AMOUNT OF INSTABILITY AND RATHER STRONG DEEP
LAYER SHEAR THE POTENTIAL EXISTS FOR ORGANIZED SEVERE STORMS, BUT
THIS IS CONDITIONAL THAT STORMS DO IN FACT DEVELOP.
GLASS
.LONG TERM: (TUESDAY THROUGH SUNDAY)
ISSUED AT 330 AM CDT MON JUL 13 2015
THE INITIAL COLD FRONT/BOUNDARY WILL PUSH THROUGH THE AREA ON
TUESDAY WITH THE MAIN IMPACT BEING ADVECTION OF LOWER DEW POINTS.
TEMPERATURES WILL REMAIN SEASONABLY HOT GIVEN THE WEST/NORTHWEST
FLOW AND LACK OF COOLING. GIVEN THE DRIER AIR IT APPEARS THAT HEAT
INDICES WILL REMAIN BELOW ADVISORY CRITERIA ALTHOUGH THE STL METRO
WILL NEED TO BE WATCHED CLOSELY. A SECOND AND BETTER DEFINED COLD
FRONT WITH COOLER AIR AND ACCOMPANYING HIGH PRESSURE WILL MOVE
INTO AND THROUGH THE AREA TUESDAY NIGHT INTO WEDNESDAY. THIS FRONT
SHOULD AT LEAST PUT THE HOT TEMPERATURES IN CHECK FOR A DAY OR
TWO. HOWEVER THE FRONT RETREATS BACK NORTHWARD WEDNESDAY NIGHT
INTO THURSDAY WITH AN ACCOMPANYING CHANCE OF SHOWERS AND
THUNDERSTORMS, WHILE ALSO ALLOWING HEAT AND HUMIDITY TO RETURN FOR
LATE WEEK. THE HEAT APPEARS TO BUILD INTO THE WEEKEND AS THE UPPER
HIGH/RIDGE CENTERED TO OUR SOUTH THEN AMPLIFIES INTO THE UPPER MS
VALLEY.
GLASS
&&
.AVIATION: (FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT)
ISSUED AT 1059 PM CDT SUN JUL 12 2015
ONLY QUESTION TONIGHT IS WHETHER PRECIPITATION WILL MAKE IT INTO
THE AREA OVERNIGHT. MOST MODELS, EXCEPT FOR THE GFS AND
OPERATIONAL HRRR, MOVE CURRENT COMPLEX(S) OVER THE UPPER MIDWEST
TO THE EAST. EXPERIMENTAL HRRR (WHICH LOADS ACTUAL RADAR DATA
FIRST) LOOKS GOOD WITH THE CURRENT COMPLEX AND ALSO KEEPS THE
MOVEMENT TO THE EAST. MAJORITY RULES SO WILL KEEP TAFS DRY. VFR
WITH SOUTH TO SOUTHWEST WIND.
SPECIFICS FOR KSTL: VFR WITH SOUTH TO SOUTHWEST WIND.
JPK
&&
.LSX WATCHES/WARNINGS/ADVISORIES:
MO...HEAT ADVISORY FROM NOON TODAY TO 8 PM CDT THIS EVENING FOR
AUDRAIN MO-BOONE MO-CALLAWAY MO-COLE MO-CRAWFORD MO-
FRANKLIN MO-GASCONADE MO-IRON MO-JEFFERSON MO-KNOX MO-LEWIS
MO-LINCOLN MO-MADISON MO-MARION MO-MONITEAU MO-MONROE MO-
MONTGOMERY MO-OSAGE MO-PIKE MO-RALLS MO-REYNOLDS MO-SHELBY
MO-ST. FRANCOIS MO-STE. GENEVIEVE MO-WARREN MO-WASHINGTON
MO.
HEAT ADVISORY UNTIL 8 PM CDT THIS EVENING FOR ST. CHARLES MO-ST.
LOUIS CITY MO-ST. LOUIS MO.
IL...HEAT ADVISORY FROM NOON TODAY TO 8 PM CDT THIS EVENING FOR ADAMS
IL-BOND IL-BROWN IL-CALHOUN IL-CLINTON IL-FAYETTE IL-GREENE
IL-JERSEY IL-MACOUPIN IL-MARION IL-MONROE IL-MONTGOMERY IL-
PIKE IL-RANDOLPH IL-WASHINGTON IL.
HEAT ADVISORY UNTIL 8 PM CDT THIS EVENING FOR MADISON IL-ST.
CLAIR IL.
&&
$$
WFO LSX
AREA FORECAST DISCUSSION...UPDATED AVIATION
NWS ST LOUIS MO
1105 PM CDT SUN JUL 12 2015
.SHORT TERM: (THROUGH LATE TONIGHT)
ISSUED AT 345 PM CDT SUN JUL 12 2015
JUST A SCATTERED DIURNAL CUMULUS FIELD ACROSS OUR AREA THIS
AFTERNOON WITH BETTER COVERAGE ACROSS THE OZARKS OF SOUTHEAST MO.
COULD NOT RULE OUT AN ISOLATED LATE AFTERNOON SHOWER/STORM IN THIS
AREA, BUT IT APPEARS THAT IT WILL BE DRY FOR THE REMAINDER OF THE
AFTERNOON INTO THE EVENING. HEAT ADVISORY CONTINUES IN EFFECT FOR
THE ST LOUIS METRO AREA WITH CURRENT HEAT INDICES AROUND 102-103
ACROSS THIS AREA THIS AFTERNOON. IT WILL BE A WARM MUGGY NIGHT
WITH SURFACE DEW POINTS IN THE 70S. CONVECTION IS EXPECTED TO
DEVELOP ACROSS THE UPPER MIDWEST AND DROP SOUTH SOUTHEASTWARD
THROUGH IL LATER TONIGHT. THERE IS SOME UNCERTAINTY WITH THE
WESTWARD EXTENT OF THIS CONVECTION AS WARMER MID LEVEL
TEMPERATURES, CAPPING SPREAD EASTWARD TONIGHT. THE GFS MODEL LOOKS
TOO FAR WEST WITH ITS QPF TONIGHT, WHILE THE NAM MODEL MAY BE TOO
FAR EAST WITH ITS QFF. DUE TO THIS UNCERTAINTY WILL JUST INCLUDE
CHANCE POPS MAINLY LATE TONIGHT ACROSS NORTHEAST MO AND WEST
CENTRAL AND SOUTHWEST IL, NORTH AND EAST OF STL. ALTHOUGH THE
CONVECTION SHOULD IN THE WEAKENING STAGES AS IT DROPS SOUTH
SOUTHEASTWARD INTO THE NORTHEASTERN PORTION OF OUR FORECAST AREA,
IT MAY STILL BE CAPABLE OF PRODUCING STRONG WIND GUSTS ACROSS
NORTHEAST MO AND WEST CENTRAL IL LATE TONIGHT.
GKS
.LONG TERM: (MONDAY THROUGH NEXT SUNDAY)
ISSUED AT 345 PM CDT SUN JUL 12 2015
UPPER LEVEL HIGH CENTERED OVER THE SOUTH-CENTRAL CONUS WILL MOVE
LITTLE OVER THE NEXT SEVEN DAYS...BUT ITS DOMINANCE OVER OUR
REGION WILL WAX AND WANE AT TIMES. THE MODELS HAVE REMAINED
CONSISTENT IN SHOWING THE DOMINANCE OF THIS UPPER HIGH FADING LATE
MONDAY...AND ROUGHLY CORRESPONDING WITH A SURFACE COLD FRONT
DROPPING THRU MONDAY NIGHT. THE UPPER HIGH`S INFLUENCE IS THEN
EXPECTED TO EXPAND HEADING INTO THURSDAY AND THE WEEKEND AND THIS
ROUGHLY CORRESPONDS TO A SURFACE WARM FRONT PUSHING BACK THRU ON
THURSDAY.
WHEN THE FRONT IS TO OUR NORTH...NAMELY THRU MONDAY AND AGAIN
HEADING INTO LATE THIS WEEK AND NEXT WEEKEND...DANGEROUS LEVELS OF
HEAT AND HUMIDITY WILL BE A REAL CONCERN AND FOR THE ONGOING
SITUATION...A HEAT ADVISORY HAS ALREADY BEEN ISSUED AND WILL COVER
MUCH OF OUR REGION BY MONDAY. THIS HANDLES WELL THE CURRENT
FORECAST AND NO CHANGES WILL BE MADE. THE POTENTIAL HEAT AND
HUMIDITY EVENT FOR LATE WEEK IS TOO FAR OUT TO DEAL WITH HEADLINES
AT THE MOMENT BUT MERITS A CLOSE WATCH.
DESPITE A COLD FRONT EXPECTED TO MOVE THRU MONDAY NIGHT AND THE
FRONT SETTLING TO OUR SOUTH THRU WEDNESDAY...THERE WILL NOT BE A
SIGNIFICANT COOLDOWN ON TEMPS BUT PERHAPS ENOUGH OF ONE TO PLACE A
HOLD ON ANY HEAT HEADLINES. MAX TEMPS ON TUESDAY ARE STILL EXPECTED
TO BE IN THE LOW-MID 90S...BUT CONFIDENCE IN THESE TEMPS IS LOWER
THAN MONDAY DUE TO LEFTOVER CLOUDS FROM FRONTAL PASSAGE AND PCPN
CHANCES FOR SOME AREAS. THE ANTICIPATED DROP IN HUMIDITY FROM
MONDAY WILL MAKE ANY TEMPORAL EXTENSION OF A HEAT ADVISORY ENOUGH IN
DOUBT TO NOT TOUCH HEADLINES WITH THIS PACKAGE AND LET SUBSEQUENT
SHIFTS TAKE ANOTHER LOOK.
PCPN CHANCES FOR MONDAY SHOULD BE CONFINED MAINLY TO SOME SECTIONS
OF SOUTHWEST IL...WHICH WILL BE ON THE EDGE OF WHAT SHOULD BE A
SIGNIFICANT SEVERE WX EVENT FURTHER TO THE EAST...AND SOME AREAS OF
WEST-CENTRAL ILLINOIS AND NORTHEAST MISSOURI LATE MONDAY AFTERNOON
WITH WHAT SHOULD BEGIN TO DEVELOP ALONG AN APPROACHING COLD FRONT.
THIS COLD FRONT IS THEN EXPECTED TO DROP THRU THE AREA MONDAY NIGHT
WITH SMALL CHANCES FOR STORMS. THE ATMOSPHERE SHOULD INITIALLY BE
WELL CAPPED BUT THIS CAP WILL ERODE ENOUGH ON APPROACH OF THE FRONT
WHERE IT SHOULD RESULT IN SCATTERED CONVECTION. FRONT IS THEN
EXPECTED TO BE TO OUR SOUTH TUESDAY AND MUCH OF WEDNESDAY BEFORE
RIDING BACK NORTH THRU OUR AREA AS A WARM FRONT WITH ADDITIONAL
CHANCES FOR STORMS.
TES
&&
.AVIATION: (FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT)
ISSUED AT 1059 PM CDT SUN JUL 12 2015
ONLY QUESTION TONIGHT IS WHETHER PRECIPITATION WILL MAKE IT INTO
THE AREA OVERNIGHT. MOST MODELS, EXCEPT FOR THE GFS AND
OPERATIONAL HRRR, MOVE CURRENT COMPLEX(S) OVER THE UPPER MIDWEST
TO THE EAST. EXPERIMENTAL HRRR (WHICH LOADS ACTUAL RADAR DATA
FIRST) LOOKS GOOD WITH THE CURRENT COMPLEX AND ALSO KEEPS THE
MOVEMENT TO THE EAST. MAJORITY RULES SO WILL KEEP TAFS DRY. VFR
WITH SOUTH TO SOUTHWEST WIND.
SPECIFICS FOR KSTL: VFR WITH SOUTH TO SOUTHWEST WIND.
JPK
&&
.LSX WATCHES/WARNINGS/ADVISORIES:
MO...HEAT ADVISORY FROM NOON TO 8 PM CDT MONDAY FOR AUDRAIN MO-BOONE
MO-CALLAWAY MO-COLE MO-CRAWFORD MO-FRANKLIN MO-GASCONADE MO-
JEFFERSON MO-KNOX MO-LEWIS MO-LINCOLN MO-MARION MO-MONITEAU
MO-MONROE MO-MONTGOMERY MO-OSAGE MO-PIKE MO-RALLS MO-SHELBY
MO-ST. FRANCOIS MO-STE. GENEVIEVE MO-WARREN MO-WASHINGTON
MO.
HEAT ADVISORY UNTIL 8 PM CDT MONDAY FOR ST. CHARLES MO-ST. LOUIS
CITY MO-ST. LOUIS MO.
IL...HEAT ADVISORY FROM NOON TO 8 PM CDT MONDAY FOR ADAMS IL-BOND IL-
BROWN IL-CALHOUN IL-CLINTON IL-FAYETTE IL-GREENE IL-JERSEY
IL-MACOUPIN IL-MARION IL-MONROE IL-MONTGOMERY IL-PIKE IL-
RANDOLPH IL-WASHINGTON IL.
HEAT ADVISORY UNTIL 8 PM CDT MONDAY FOR MADISON IL-ST. CLAIR IL.
&&
$$
WFO LSX
AREA FORECAST DISCUSSION
NWS OMAHA/VALLEY NE
310 AM CDT MON JUL 13 2015
.SHORT TERM...(TODAY THROUGH WEDNESDAY)
ISSUED AT 310 AM CDT MON JUL 13 2015
HEAT AND HUMIDITY TODAY...ISOLATED STORMS INTO MID MORNING AND
THEN SLIGHT CHANCE OF TSTMS LATE TODAY INTO THIS EVENING ARE THE
PRIMARY FORECAST CONCERNS THROUGH THIS PERIOD.
UPPER AIR CHARTS FROM LAST EVENING SHOWED THE FOLLOWING. AT 300 MB
A JET STREAK OF 80-90 KNOTS EXTENDED FROM ERN WY ACROSS SRN SD. AT
500 MB...WEAK HEIGHT FALLS WERE MOVING EWD ACROSS THE DAKOTAS AND
MN AND RIDGE ALOFT WAS STILL CENTERED OVER TX. THERMAL RIDGE AT
700 MB STRETCHED FROM NM INTO CO AND KS. ACROSS NEBRASKA...700 MB
TEMPERATURES WERE GENERALLY 12-13 DEGREES C. THERMAL RIDGE AT 850
MB WAS LOCATED FROM NM INTO WRN SD. DRIER AIR WAS OVER THE HIGH
PLAINS BUT 850 MB DEWPOINTS WERE IN THE TEENS FROM IA BACK INTO
ERN NE. THE KOAX SOUNDING FROM 00Z WAS FAIRLY MOIST...WITH A
PRECIPITABLE WATER OF 1.48 INCHES. SURFACE ANALYSIS AT 08Z SHOWED
A TROUGH OF LOW PRESSURE CURVING FROM THE ERN SD INTO NWRN KS.
AHEAD OF THIS TROUGH...DEWPOINTS WERE MOSTLY IN THE 70S BUT DROP
TO 60S AND 50S WEST OF THE TROUGH.
JUST HOW FAST DRIER AIR WILL BE ABLE TO MOVE IN TODAY WILL HAVE A
BIG IMPACT ON HEAT INDICES. LEFT PREVIOUSLY ISSUED HEAT ADVISORY
AS IS...BUT MAY NEED A SLIGHT ADJUSTMENT LATER TODAY. OTHERWISE...
ISOLATED TSRA WERE OCCURRING OVER PARTS OF NERN NE. THESE WERE
VERY HIGH BASED...ABOVE THE MID LEVEL CAP AND POSSIBLY GETTING
SOME SUPPORT BY THE JET STREAK MENTIONED EARLIER AND VERY WEAK
MID LEVEL HEIGHT FALLS. THESE MAY LAST INTO MID MORNING AS THEY
CONTINUE TO TRACK EAST. AFTER THAT...THE REST OF THE DAY IS
EXPECTED TO BE DRY...EXCEPT DID INCLUDE A SLIGHT CHANCE OF TSTMS
IN OUR FAR SRN COUNTIES TOWARD 6 PM AND THEN THROUGH EARLY THIS
EVENING. HRRR AND SOME OF THE OTHER HIGH RESOLUTION MODELS HAVE
GENERALLY BEEN TOO BULLISH WITH STORM DEVELOPMENT/COVERAGE THE
PAST FEW DAYS...BUT WEAK SIGNALS ARE THERE FOR POSSIBLE ISOLATED
ACTIVITY LATER TODAY. KEPT HIGHS CLOSE TO PREVIOUS FORECAST...
IN THE MID AND UPPER 90S.
THE 00Z GFS DEVELOPED MORE PCPN OVERNIGHT ALONG THE KS/NE BORDER
BUT FELT THAT WAS OVERDONE AT THIS POINT. HAVE MOST OF THE AREA
DRY OVERNIGHT WITH LOWS IN THE MID OR UPPER 60S NORTH AND LOWER
70S SOUTH. RIGHT NOW...TUESDAY LOOKS TO BE A FEW DEGREES COOLER
THAN TODAY...WITH HEAT INDICES STAYING MAINLY BELOW 100.
RAIN CHANCES START TO INCREASE TUESDAY NIGHT AND THEN MORE ON
WEDNESDAY AS HEIGHTS DECREASE A BIT. THIS WILL ALLOW SHORTWAVE
ENERGY TO MOVE OUT OF THE WESTERN UNITED STATES TROUGH AND TAP
INTO SOME MONSOONAL MOISTURE. DUE TO MORE CLOUD COVER...HAVE
HIGHS WEDNESDAY MAINLY 85 TO 90.
.LONG TERM...(WEDNESDAY NIGHT THROUGH SUNDAY)
ISSUED AT 310 AM CDT MON JUL 13 2015
500 MB RIDGE WILL GENERALLY REMAIN CENTERED OVER LA OR ERN TX
THROUGH THIS PERIOD. OUR AREA WILL BE MOSTLY IN SOUTHWEST MID
LEVEL FLOW...AHEAD OF THE TROUGH LOCATED MAINLY ACROSS THE PACIFIC
NORTHWEST. TEMPERATURES WILL GENERALLY BE SEASONAL WITH OCCASIONAL
SMALL CHANCES FOR PCPN. BEST CHANCES LOOK TO BE WEDNESDAY NIGHT
INTO THURSDAY AND THEN AGAIN SUNDAY NIGHT.
&&
.AVIATION...(06Z TAFS FOR KOFK...KLNK AND KOMA.)
ISSUED AT 1135 PM CDT SUN JUL 12 2015
DESPITE LARGE CAPE VALUES AND GOOD SHEAR ACROSS THE
AREA...CONVECTION HAS HAD A HARD TIME MAINTAINING ITSELF THIS
EVENING WEST OF THE AREA. MAY SEE SOME BRIEF HIT OR MISS THUNDER
AS SURFACE TROUGH MOVES ACROSS THE AREA DURING THE PERIOD BUT TOO
LIMITED TO MENTION. VFR CONDITIONS EXPECTED TO PREVAIL WITH WINDS
BECOMING NORTHERLY BEHIND THE TROUGH.
&&
.OAX WATCHES/WARNINGS/ADVISORIES...
NE...HEAT ADVISORY FROM 1 PM THIS AFTERNOON TO 8 PM CDT THIS EVENING
FOR NEZ045-051>053-066>068-078-088>093.
IA...HEAT ADVISORY FROM 1 PM THIS AFTERNOON TO 8 PM CDT THIS EVENING
FOR IAZ055-056-069-079-080-090-091.
&&
$$
SHORT TERM...MILLER
LONG TERM...MILLER
AVIATION...FOBERT
AREA FORECAST DISCUSSION
NWS OMAHA/VALLEY NE
1136 PM CDT SUN JUL 12 2015
.SHORT TERM...(TONIGHT THROUGH WEDNESDAY)
ISSUED AT 319 PM CDT SUN JUL 12 2015
FEELS LIKE TEMPERATURES OUT THERE ARE VERY HOT...WITH MANY LOCATIONS
REPORTING HEAT INDICES AROUND 105 AT 3 PM. WE ARE ANTICIPATING THIS
AGAIN MONDAY FOR QUITE A FEW COUNTIES IN OUR SOUTHEASTERN CWA AND
IS THE MAIN CONCERN IN THE NEXT 24 HOURS.
LATEST WATER VAPOR IMAGERY AND RAP 500MB ANALYSIS SHOWS LARGE HIGH
PRESSURE DOME OVER THE SOUTHERN PLAINS WITH A SHORTWAVE TROUGH
MOVING ACROSS THE NORTHERN PLAINS. VERY HIGH SFC DEWPOINTS REMAIN
OVER THE AREA THIS AFTERNOON WITH READINGS VARYING BETWEEN THE
LOWER 70S IN OUR WEST TO THE UPPER 70S IN OUR EAST. WE ALSO HAVE
THE SPORADIC IOWA AWOS VALUES IN THE LOW 80S. LATEST SURFACE
ANALYSIS SHOWS LOW PRESSURE CENTERED OVER SOUTHEASTERN NORTH
DAKOTA WITH A SECONDARY LOW ACROSS SOUTHWEST KANSAS. A TROUGH IN
BETWEEN THESE TWO AREAS CURRENTLY EXTENDS ACROSS OUR FAR
NORTHWESTERN COUNTIES AND THIS FEATURE WILL CONTINUE TO SLOWLY
PUSH EAST ACROSS THE FORECAST AREA THROUGH MONDAY...BRINGING IN
LOWER DEWPOINTS TO THE AREA.
TEMPERATURES SHOULD MIX OUT INTO THE UPPER 90S NEAR THE BOUNDARY
MONDAY. COMBINED WITH MID-UPPER 70S DEWPOINTS IN THE SOUTHEASTERN
HALF OF THE CWA...WE SHOULD PUSH HEAT INDICES INTO THE ADVISORY
CATEGORY ONCE AGAIN SO DID HOIST AN ADVISORY FOR MONDAY.
WARM CONDITIONS WILL CONTINUE ON TUESDAY ALTHOUGH WILL NOT BE QUITE
AS HOT. HEAT INDICES WILL BE LOWER AS WELL WITH DEWPOINTS IN THE
60S. BY TUESDAY NIGHT...THE FIRST IN A SERIES OF SEVERAL
SHORTWAVES WILL BE PASSING THROUGH THE MID LEVELS. WITH AMPLE
MOISTURE IN THE ATMOSPHERE...WE CANNOT RULE OUT PCPN CHANCES WITH
ANY OF THESE WAVES. CONVECTION MAY BEGIN AS EARLY AS TUESDAY
EVENING OVER THE HIGH PLAINS ASSOCIATED WITH THE FIRST WAVE...THEN
SPREAD EAST INTO THE CWA OVERNIGHT TUESDAY NIGHT INTO WEDNESDAY
MORNING.
.LONG TERM...(WEDNESDAY NIGHT THROUGH SUNDAY)
ISSUED AT 319 PM CDT SUN JUL 12 2015
TSTM CHANCES CONTINUE WEDNESDAY NIGHT AS ANOTHER STRONG SHORTWAVE
MOVES ACROSS THE HIGH PLAINS DURING THE AFTERNOON WEDNESDAY AND
INTO OUR CWA WEDNESDAY EVENING. A STRONG SOUTHWESTERLY LOW LEVEL
JET SHOULD AID CONTINUED CONVECTION THROUGH THE OVERNIGHT HOURS.
THE AREA WILL REMAIN IN WEST/SOUTHWESTERLY FLOW ALOFT THROUGH NEXT
WEEKEND BRINGING SEVERAL SMALL CHANCES OF TSTMS THROUGH THE
PERIOD. TEMPS SHOULD BE QUITE SEASONABLE FOR THIS TIME OF YEAR.
&&
.AVIATION...(06Z TAFS FOR KOFK...KLNK AND KOMA.)
ISSUED AT 1135 PM CDT SUN JUL 12 2015
DESPITE LARGE CAPE VALUES AND GOOD SHEAR ACROSS THE
AREA...CONVECTION HAS HAD A HARD TIME MAINTAINING ITSELF THIS
EVENING WEST OF THE AREA. MAY SEE SOME BRIEF HIT OR MISS THUNDER
AS SURFACE TROUGH MOVES ACROSS THE AREA DURING THE PERIOD BUT TOO
LIMITED TO MENTION. VFR CONDITIONS EXPECTED TO PREVAIL WITH WINDS
BECOMING NORTHERLY BEHIND THE TROUGH.
&&
.OAX WATCHES/WARNINGS/ADVISORIES...
NE...HEAT ADVISORY FROM 1 PM TO 8 PM CDT MONDAY FOR NEZ045-051>053-
066>068-078-088>093.
IA...HEAT ADVISORY FROM 1 PM TO 8 PM CDT MONDAY FOR IAZ055-056-069-
079-080-090-091.
&&
$$
SHORT TERM...KERN
LONG TERM...KERN
AVIATION...FOBERT
AREA FORECAST DISCUSSION...UPDATED
NWS ALBUQUERQUE NM
1131 PM MDT SUN JUL 12 2015
.AVIATION...
06Z TAF CYCLE
SHOWERS AND THUNDERSTORMS HAVE LARGELY DISSIPATED ACROSS THE
WESTERN HALF OF NEW MEXICO...AND THIS TREND SHOULD CONTINUE INTO
THE EARLY MORNING HOURS MONDAY. ACTIVITY HAS LARGELY TURNED TO
BATCHES OF LIGHT TO MODERATE RAIN WITH ONLY A FEW EMBEDDED
CONVECTIVE OR THUNDERSTORM CELLS LINGERING. THIS WILL LIMIT THE
AVIATION HAZARDS...BUT SOME ERRATIC GUSTY WINDS COULD ACCOMPANY
THESE STRONGER EMBEDDED CELLS. SCATTERED TO NUMEROUS
THUNDERSTORMS WILL REDEVELOP MONDAY AFTERNOON. STORMS ON MONDAY
WILL AGAIN FAVOR THE WESTERN TO CENTRAL AREAS OF NEW MEXICO WITH
THE USUAL THREATS OF GUSTY DOWNBURST WINDS...HEAVY DOWNPOURS...AND
SMALL HAIL.
52
&&
.PREV DISCUSSION...348 PM MDT SUN JUL 12 2015...
.SYNOPSIS...
AS UPPER LEVEL HIGH PRESSURE REMAINS ANCHORED OVER THE SOUTHERN
PLAINS A RATHER CLASSIC MONSOON MOISTURE PLUME WILL CONTINUE TO
BRING SCATTERED THUNDERSTORMS WITH LOCALLY HEAVY RAINFALL TO MUCH
OF CENTRAL AND WESTERN NEW MEXICO THIS EVENING THROUGH AT LEAST
MID WEEK. STORM COVERAGE IS EXPECTED TO TREND DOWN SOMEWHAT THURSDAY
AS DRY AIR ALOFT WORKS IN FROM THE WEST. THE MOISTURE PLUME RE-
ESTABLISHES ITSELF FRIDAY AND SATURDAY FOR A RETURN TO SCATTERED
ACTIVITY.
&&
.DISCUSSION...
UPPER LEVEL HIGH CENTERED NEAR LUBBOCK TX THIS AFTERNOON. MODELS
IN VERY GOOD AGREEMENT THAT DEEP SUBTROPICAL MOISTURE WILL CONTINUE
STREAMING INTO WESTERN AND CENTRAL NM THROUGH AT LEAST WEDNESDAY.
BOTH 18Z NAM12 AND 20Z HRRR PICKING UP ON PERTURBATION/VORT LOBE
CURRENTLY MOVING INTO FAR SE ARIZONA. BOTH MODELS BRING THIS
FEATURE INTO SWRN AND WEST CENTRAL NM AFTER MIDNIGHT...HELPING TO
KEEP SHOWERS AND STORMS GOING THERE THROUGH EARLY MONDAY MORNING.
MODELS CONTINUE TO SHIFT THE UPPER HIGH SLIGHTLY EASTWARD MONDAY
AND TUESDAY...ALLOWING STORMS TO PROPAGATE EWD MORE EASILY INTO
THE NE AND EAST-CENTRAL PLAINS. MODELS REMAIN IN RELATIVELY GOOD
AGREEMENT THAT SOME DRIER AIR ALOFT WILL ATTEMPT TO WORK INTO NW
AND NORTH-CENTRAL NM THURSDAY...LEADING TO A POSSIBLE DOWN DAY
THERE. THE DEEP MOISTURE PLUME HANGS TOUGH ELSEWHERE.
12Z GFS PROGGING AN INCREASE IN SELY WINDS BETWEEN THE UPPER HIGH
AND WHAT IS NOW TROPICAL STORM DOLORES. THIS INCREASING FLOW
HAS THE POTENTIAL TO TAP DEEP SUBTROPICAL MOISTURE AND DEEP
CONVECTION OVER FAR NW MEXICO AND SRN ARIZONA. 12Z GFS GOES SO FAR
AS TO DEVELOP A WARM CORE LOW OVER SE AZ/WRN NM THURSDAY NIGHT
AND FRIDAY. SUCH A FEATURE WOULD RESULT IN A MARKED INCREASE IN
HEAVY RAIN/FLASH FLOODING POTENTIAL FRIDAY INTO FRIDAY NIGHT. TOO
FAR OUT AT THIS POINT TO NAIL DOWN THE TIMING OF A FEATURE YET TO
DEVELOP BUT IT WILL BE CLOSELY MONITORED IN THE COMING DAYS.
SUNDAY COULD BE THE NEXT DOWNDAY AS THE UPPER HIGH ATTEMPTS TO
RETROGRADE WWD INTO SRN AZ. CONFIDENCE IN THIS SOLUTION REMAINS
LOW AS 12Z ECMWF KEEPS THE UPPER HIGH CENTER OVER SE NM...KEEPING
WRN AND NRN NM ACTIVE SUNDAY INTO EARLY NEXT WEEK.
33
&&
.FIRE WEATHER...
THE SHOWER AND THUNDERSTORM CROP TODAY IS GREATER IN
NUMBER AND AT LEAST AS VIGOROUS AS WAS THE CASE SAT...MOST TODAY
BEING ACROSS THE WEST TWO THIRDS OF THE STATE. MONSOONAL MOISTURE
PLUME HOLDING FIRM ACROSS THIS GENERAL AREA AND INTO EAST AZ. NO
MAJOR CHANGE IN OVERALL PATTERN FOR THE WORK WEEK...THOUGH FCST
MODELS ARE HINTING AT ANY SIGNIFICANT DRYING TO BE THU TO FRI AND
MAY BE SHORTER IN DURATION THAN WHAT WAS INDICATED THE PAST DAY OR
TWO. LESS INDICATION THAN 12 TO 24 HRS AGO OF A WEAK BACK DOOR FRONT
PUSHING INTO NE NM NEAR MON TO MON NIGHT PERIOD...THOUGH IF
CONVECTION DOES RAMP UP IN SE CO THERE STILL WILL LIKELY BE AT LEAST
A STORM COMPLEX OUTFLOW BOUNDARY INTO THE FAR NE. IF IT DOES NOT
HAPPEN THEN STORM COVERAGE IN NE NM MAY NOT INCREASE ALL THAT MUCH.
FCST MODELS FOR THE MOST PART CONTINUING TO DELAY...A FEW EVEN
ELIMINATE...THE BUILDING OF THE UPPER HIGH CENTER OVER THE STATE...
LEAVING THE MOISTURE PLUME MORE INTACT OVER WEST HALF OF NM. NEXT
WEEKEND INTO MID NEXT WEEK A TROPICAL SYSTEM IS STILL INDICATED AS
MOVING UP AND OVER THE RIDGE INTO CA WITH THE BULK OF ITS MOISTURE
WELL TO OUR WEST.
HIGH TEMPERATURES WILL REMAIN BELOW AVERAGE WEST...BUT RISE TO
AVERAGE OR SLIGHTLY ABOVE...THIS WEEK. VENT RATES GENERALLY GOOD TO
EXCELLENT ALTHOUGH SOME POCKETS OF FAIR TO POOR RATES WILL EXIST
NORTH AND WEST THROUGH WED...WITH SOME DECREASE POSS THU.
43
&&
.ABQ WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
346 AM EDT MON JUL 13 2015
.SYNOPSIS...
AN INLAND TROUGH AND HIGH PRESSURE OFFSHORE WILL PROVIDE A
CHANCE OF SHOWERS AND THUNDERSTORM EACH DAY THROUGH MID WEEK. A FEW
THUNDERSTORMS COULD BECOME STRONG TO SEVERE EACH AFTERNOON...
ESPECIALLY LATER TUESDAY AS LOW PRESSURE DEEPENS OVER THE AREA.
DRIER WEATHER WILL DEVELOP ON THURSDAY BUT A RETURN TO MORE HUMID
WEATHER WILL RETURN DURING THE WEEKEND.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 340 AM MONDAY...LONGWAVE UPPER PATTERN IS PRETTY MUCH SET FOR
THE REMAINDER OF THIS WEEK...WITH UPPER RIDGING ACROSS THE MID-
SECTION OF THE U.S. AND UPPER TROFFING LYING JUST OFF THE MID-
ATLANTIC AND SOUTHEAST COASTS. THIS LEAVES THE FORECAST AREA UNDER
THE INFLUENCE OF NW FLOW ALOFT...ACCOMPANIED BY THE OCCASIONAL S/W
TROF OR VORT DROPPING SOUTHEAST AFFECTING ALL OR PORTIONS OF THE FA
THIS PERIOD...AND SUBSEQUENT PERIODS THERE-AFTER.
AT THE MOMENT...THE FA IS UNDER THE INFLUENCE OF A MID-LEVEL S/W
TROF EMBEDDED IN THIS UPPER NW FLOW. THE BEST DYNAMICS ACCORDING TO
THE RAP WILL STAY NORTH OF THE FA. ENOUGH JUICE IE. CAPE AND
MOISTURE IDENTIFIED BY MODEL SOUNDINGS REMAINS AVAILABLE FOR
CONVECTION THIS MORNING...MAINLY IN THE FORM OF SHOWERS. ITS NOT
UNTIL A FEW HRS AFTER DAYBREAK THAT MODEL SOUNDINGS INDICATE A MORE
FAVORABLE PROFILE...IE. INCREASING CAPE DUE TO THE DAYS
INSOLATION...FOR THUNDERSTORMS TO OCCUR. FOR THIS AFTERNOON AND
EVENING...MODELS...ESPECIALLY THE NAM...INDICATE SOME NVA SUBSIDENCE
ALOFT TO PUSH ACROSS THE FA IN THE WAKE OF THIS CURRENT MID-LEVEL
S/W TROF. WILL LEAN TOWARDS THE NAM...AND TONE DOWN THE POPS ACROSS
THE FA...ESPECIALLY ACROSS THE ILM SC COUNTIES. BEAR IN MIND STILL
THE THREAT FOR CONVECTION JUST NOT AS PRONOUNCED AS THE HRS LEADING
UP TO THIS AFTERNOON. SFC CONVERGENCE ALONG THE DEEPENING SFC TROF
ACROSS THE EASTERN CAROLINAS WILL AID THE CONTINUED LOW THREAT OF
CONVECTION THIS AFTN AND EVENING.
FOR THE LATE EVENING HOURS INTO THE PRE-DAWN HRS OF TUE...THE FA
ONCE AGAIN BECOMES UNDER THE INFLUENCE OF A MID-LEVEL S/W
TROF...WITH THE BEST DYNAMICS FROM THIS FEATURE AFFECTING MAINLY THE
ILM NC PORTIONS OF THE FA AND FURTHER NORTHWARD. HAVE INCREASED POPS
DURING THIS TIME PERIOD...HIER ACROSS THE ILM NC CWA. THERE IS A
POSSIBILITY THAT A NOCTURNAL MCS/MCC MAY DEVELOP UPSTREAM AND
EVENTUALLY DROP TO THE SOUTHEAST AND AFFECT THE FA LATE TONIGHT.
FOR MAX/MIN TEMPS...DID A BLEND OF AVBL MOS GUIDANCE. FOR MAX TEMPS
ONLY...LOWERED THIS BLEND BY A DEGREE OR 2 AS A RESULT OF MORE
WIDESPREAD OPAQUE CLOUDINESS AND THE SHRA/TSRA THREAT.
&&
.SHORT TERM /TUESDAY THROUGH WEDNESDAY NIGHT/...
AS OF 340 AM MONDAY...ACTIVE PERIOD OF WEATHER EXPECTED TUESDAY INTO
WEDNESDAY...WITH AN ENHANCED RISK FOR SEVERE WEATHER HIGHLIGHTED BY
THE STORM PREDICTION CENTER ACROSS OUR WEST/NORTHWEST FORECAST AREA
TUESDAY. DURING TUESDAY STRONGER IMPULSES WILL APPROACH IN THE
NORTHWEST FLOW ALOFT WHILE AN H3 JET NOSES INTO THE CAROLINAS AS AN
INLAND SURFACE TROUGH STRENGTHENS. STRONG INSTABILITY IS EXPECTED
WITH BREEZY SOUTH-SOUTHWESTERLY FLOW PREVAILING EAST OF THE TROUGH.
THE PRESSURE GRADIENT WILL LIKELY LEAD TO A SEGMENTED RESULTANT
BOUNDARY ALONG THE COAST. OVERALL...THE PATTERN WILL SUPPORT
VEERING/INCREASING WINDS WITH HEIGHT AND SUBSEQUENT HELICITY IN
EXCESS OF 300 M2/S2 ACROSS INLAND AREAS. AS A RESULT...THINK THE
PRIMARY SEVERE WEATHER THREAT LATER TUESDAY WILL BE FROM DAMAGING
WINDS WITH SOME LARGE HAIL POSSIBLE...AND GIVEN THE AFOREMENTIONED
HELICITY CAN/T RULE OUT TORNADOES.
DURING WEDNESDAY...THE SURFACE TROUGH REMAINS INLAND WHILE THE H5
SHORT WAVE TROUGH WILL BEGIN SHIFTING OFF THE MID-ATLANTIC AND
CAROLINA COASTS DURING THE EVENING. THE PASSAGE OF THIS FEATURE
LEADS TO HIGHER CONFIDENCE THAT THE SURFACE BOUNDARY WILL FINALLY
PUSH OFF THE COAST LATE WEDNESDAY NIGHT. INSTABILITY MAY BE LOWER
COMPARED TO TUESDAY PER BUFKIT DURING WEDNESDAY...HOWEVER
ENOUGH WILL EXISTS ALONG WITH DECENT PRECIPITABLE WATER AND SUPPORT
ALOFT TO CONTINUE GOOD CHANCE SHOWERS/TSTMS. A FEW OF THESE STORMS
MAY BECOME STRONG TO SEVERE AS WELL. POPS WILL TREND LOWER WEDNESDAY
NIGHT AS THE TROUGH PUSHES FARTHER EAST. MAV MAX TEMPERATURES
WEDNESDAY MAY BE ON THE HIGH SIDE GIVEN THE COVERAGE OF STORMS
EXPECTED.
&&
.LONG TERM /THURSDAY THROUGH SUNDAY/...
AS OF 340 AM MONDAY...THE H5 SHORTWAVE TROUGH WILL BE OFF THE MID-
ATLANTIC COAST EARLY THURSDAY...WHILE AT THE SURFACE THE TROUGH WILL
SHIFT OFFSHORE AS WEAK LOW PRESSURE EVOLVES OFF THE OUTER BANKS. THE
GFS HAS TRENDED TOWARD THIS SOLUTION OVER THE LAST DAY AND
CONFIDENCE IS INCREASING THAT THE PRECIPITABLE WATER WILL LOWER AND
THE BEST SURFACE FORCING WILL REMAIN OFFSHORE ASSOCIATED WITH THE
TROUGH DURING THURSDAY. AS A RESULT...LOWERED MAX TEMPERATURES A
CATEGORY AND LOWERED POPS AS WELL. BY FRIDAY NIGHT THE MID/UPPER
SUBTROPICAL RIDGE WILL BEGIN DRIFTING BACK TO THE WEST FROM THE MS
VALLEY ALLOWING A WEAK TROUGH TO BECOME RE-ESTABLISHED ACROSS THE
EAST COAST THIS WEEKEND. MEX GUIDANCE HAS TRENDED COOLER LIKELY
SINCE THE SURFACE FLOW IS ONSHORE...VERSUS THE HUMID SOUTHWEST FLOW
WE HAVE EXPERIENCED MULTIPLE DAYS THIS SUMMER. THUS...LOWERED MAX
TEMPS THIS WEEKEND...HOWEVER IN THE END MAX TEMPS MAY NEED TO BE
LOWERED ANOTHER CATEGORY OR TWO IF BETTER CONSISTENCY DEVELOPS IN
UPCOMING MODEL RUNS.
&&
.AVIATION /06Z MONDAY THROUGH FRIDAY/...
AS OF 06Z...MAINLY VFR CONDITIONS TO CONTINUE THROUGH THE EARLY
MORNING HOURS WITH ISOLATED -SHRA POSSIBLE WITHIN THE NW FLOW
ALOFT.
ON THE WHOLE...EXPECT VFR CONDITIONS TO DOMINATE THROUGHOUT DAYTIME
MON THRU MON EVENING. THE TIMING AND EXACT LOCATION OF
ISOLATED/SCATTERED SHOWERS AND THUNDERSTORMS WILL BE DIFFICULT TO
PINPOINT AHEAD OF A WEAK UPPER LEVEL IMPULSE WITHIN THE NW FLOW
ALOFT. AGAIN...THE TIMING FOR BRIEF PERIODS OF MVFR AND EVEN
POSSIBLE IFR FROM THE STRONGER CONVECTION...REMAINS THE CHALLENGE.
FOR NOW WILL INDICATE VCNTY SHRA ALL TERMINALS FOR THIS MORNING.
THEN...TRANSITION TO TSRA DURING DAYTIME/EVENING MONDAY. WINDS
SSE TO SW AT 3 TO 6 KT THIS MORNING...BECOMING 6 TO 12 KT DURING
DAYTIME/EVENING MONDAY...WITH POSSIBLE GUSTS 15+ KT ALONG THE
IMMEDIATE COAST.
EXTENDED OUTLOOK...POTENTIAL FOR BRIEF PERIODS OF MVFR IN
SHRA/TSRA. OTHERWISE EXPECT VFR.
&&
.MARINE...
NEAR TERM /THROUGH TONIGHT/...
AS OF 340 AM MONDAY...THE STORY FOR THIS PERIOD WILL BE THE
INCREASING SSW TO SW WINDS ACROSS THE AREA WATERS FROM MIDDAY THRU
TONIGHT...AND INTO SUBSEQUENT PERIODS. THIS A RESULT OF THE SFC PG
TIGHTENING BETWEEN AN AMPLIFIED NE-SW ORIENTED SFC TROF ACROSS THE
EAST-CENTRAL CAROLINAS...AND STRONG RIDGING FROM HIGH PRESSURE
CENTERED OVER THE HIGH SEAS WELL OUT IN THE ATLANTIC. LOOK FOR WIND
SPEEDS TO INCREASE TO AROUND 15 KT LATER THIS AFTERNOON...AND
FURTHER INCREASE TO A SOLID 15 TO 20 KT WITH POSSIBLE GUSTS UP TO 25
KT LATER TONIGHT. THE GUSTS IN PART FROM A 30+ KT LOW LEVEL JET
OCCURRING OVER THE AREA WATERS...VIA VARIOUS MODEL SOUNDINGS FOR
FRYING PAN SHOALS.
SIGNIFICANT SEAS WILL INITIALLY RUN AROUND 2 FT THRUOUT...THEN BEGIN
BUILDING TO AROUND 3 FT BY EARLY THIS EVENING...AND THEN FURTHER
BUILD TO 3 TO 5 FT THRUOUT BY LATE THIS EVENING AND THRU THE PRE-
DAWN TUE HOURS. A LAZY ESE 1 TO 1.5 FOOT GROUND SWELL WILL INITIALLY
DOMINATE THE SIG. SEAS. AS WINDS INCREASE...LOOK FOR LOCALLY
PRODUCED WIND DRIVEN WAVES AT 4 TO 5 SECOND PERIODS TO DOMINATE
LATE THIS AFTERNOON AND DEFINITELY DURING TONIGHT.
SHORT TERM /TUESDAY THROUGH WEDNESDAY NIGHT/...
AS OF 340 AM MONDAY...MARGINAL SMALL CRAFT CONDITIONS ARE POSSIBLE
TUESDAY AFTERNOON INTO WEDNESDAY AS A RESULT OF A TIGHTENED PRESSURE
GRADIENT AND RESULTANT SOUTHWEST FETCH. WIND WAVES WILL DOMINANT
DURING THIS PERIOD AS WELL AS THE BULK OF THE SPECTRAL WAVE ENERGY
IS FOCUSED IN THE 5-6 SEC RANGE. SIGNIFICANT WAVE HEIGHTS WILL BE IN
THE 3-5 FT WITHIN 10 NM AND POSSIBLE 5-6 FOOTERS ACROSS THE OUTER
WATERS. SEAS WILL SLOWLY SUBSIDE LATE WEDNESDAY NIGHT AS THE SURFACE
TROUGH PUSHES OFF THE COAST ALLOWING THE SOUTHWEST FETCH TO WEAKEN
AND VEER WITH ITS PASSAGE.
LONG TERM MARINE/THURSDAY THROUGH FRIDAY/
AS OF 340 AM MONDAY...INCREASING CONFIDENCE THAT THE SURFACE TROUGH
WILL SHIFT ACROSS THE WATERS BY THURSDAY MORNING AS WEAK LOW
PRESSURE EXISTS OFF THE OUTER BANKS. AS THIS COMES TO FRUITION THE
RATHER LIGHT FLOW WILL BECOME OFFSHORE...THEN VEER TO A LIGHT
NORTHEAST FLOW AS THE LOW EXITS TO THE NORTHEAST DURING THE EARLY
AFTERNOON. AS A WEAK RIDGE BUILDS IN FROM THE NORTHEAST THE
NORTHEAST TO EAST FLOW WILL PERSIST THROUGH FRIDAY. THINK CHANCES
FOR SHOWERS/TSTMS WILL DECREASE THURSDAY...WITH A FEW STORMS
POSSIBLE FRIDAY.
&&
.ILM WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
NC...NONE.
MARINE...NONE.
&&
$$
NEAR TERM...DCH
SHORT TERM...SRP
LONG TERM...SRP
AVIATION...DCH
AREA FORECAST DISCUSSION
NWS CHARLESTON WV
223 AM EDT MON JUL 13 2015
.SYNOPSIS...
UPPER LEVEL DISTURBANCES IN NORTHWEST FLOW THROUGH WEDNESDAY. WEAK
RIDGING ALOFT THURSDAY.
&&
.NEAR TERM /THROUGH TODAY/...
800 PM UPDATE...
INCREASED POPS TONIGHT FROM THE C LOWLANDS AND ESPECIALLY INTO THE
N LOWLANDS/MTNS. A WEAK LOW PRESSURE SYS OVER OH WILL DRIFT SE
INTO THE AREA OVERNIGHT. THIS COMBINED WITH SOME MID LEVEL LIFT
OVER THE AREA SHOULD ALLOW SHRA INCREASE IN COVERAGE THIS AFTER
MIDNIGHT. AS THIS SYS SPIRALS INTO THE AREA...EXPECT LOW CIGS TO
DEVELOP ALONG WITH PATCHY FG.
PREVIOUS DISCUSSION BELOW...
LATEST SATELLITE IMAGERY DEPICTS A RATHER CHAOTIC IMAGE OVER THE
MIDDLE ATLANTIC STATES THIS AFTERNOON...WITH SEVERAL FEATURES OF
NOTE. ACROSS CENTRAL AND EASTERN OHIO THERE IS A FAIRLY WELL
DEFINED SHORTWAVE KICKING OFF SHOWER ACTIVITY ACROSS NORTHEASTERN
OHIO. SKIES HAVE STARTED TO CLEAR SOME ACROSS CENTRAL AND EASTERN
KY...IN THE WAKE OF MCS WHICH MOVED THROUGH THIS MORNING. SEVERAL
OUTFLOW BOUNDARIES CAN BE SEEN IN EASTERN TN AND SOUTHERN KY AS
WELL. THESE HELPING TO KICK OFF CONVECTION. ACROSS WEST VIRGINIA A
SOLID MID DECK OF BLOW CLOUDS HAVE IMPEDED DAYTIME HEATING. THUS
THERE IS A LACK OF CONVECTION INITIATION SO FAR. HOWEVER...BL
HEATING ACROSS THE ELEVATED TERRAIN ALLOWING SOME CU TO FORM.
LATEST SHORT TERM MODELS HAVE BEEN SLOW TO CATCH ON WITH ALL OF
THESE SMALLER SCALE FEATURES. HOWEVER...LATEST RUNS SEEM TO SHOW A
TREND THAT PRECIPITATION SHOULD REMAIN SUPPRESSED FOR THE VERY NEAR
TERM WITH THE RUC AND HRRR IN GENERAL AGREEMENT. AS SHORTWAVE TRACKS
ACROSS THE NORTHERN TIER THIS EVENING...RAMPS POPS BACK UP. FOR
MONDAY...BROAD BUSHED POPS WITH AN EYE ON FEATURES THAT MAY TRACK
ACROSS IN NORTHWEST FLOW.
&&
.SHORT TERM /TONIGHT THROUGH THURSDAY/...
GOING TO KEEP IT SHORT THIS MORNING DUE TO OTHER PRESSING CONCERNS.
LAST OF THE UPPER LEVEL TROUGHS IN THE NORTHWEST FLOW DIPS INTO THE
CENTRAL APPALACHIANS KEEPING THE THREAT FOR ACTIVE WEATHER GOING
THROUGH TUESDAY NIGHT AND ENDING WEDNESDAY. SPC DAY 2 OUTLOOK IS
LARGELY UNCHANGED WITH THE THREAT FOR SEVERE WEATHER PRIMARILY OVER
THE SOUTHERN TWO THIRDS OF THE FORECAST AREA. WITH WIND BEING THE
MAIN DRIVER. THE ACTIVE PATTERN WARRANT LIKELY POPS FOR THE BULK OF
TUESDAY INTO TUESDAY NIGHT...EVEN THOUGH IT WILL BE DIFFICULT TO
DETERMINE CONVECTIVE INITIATION AND TIMING.
PATTERN FINALLY TRANSITIONS TO MORE RIDGING ALOFT WEDNESDAY NIGHT
AND THURSDAY WITH HIGH PRESSURE INFLUENCES FROM THE NORTH AT THE
SURFACE. THURSDAY WILL LIKELY BREAK THE CONSECUTIVE DAYS WITH
PRECIPITATION STREAK IF NOT WEDNESDAY.
&&
.LONG TERM /THURSDAY NIGHT THROUGH SUNDAY/...
FOR WEDNESDAY...THE AREA WILL STILL BE UNDER THE INFLUENCE OF A
BROAD UPPER LEVEL TROUGH AND NORTHWEST FLOW...KEEPING THE AREA UNDER
CHANCES FOR ADDITIONAL SHOWERS AND THUNDERSTORMS LESS NUMEROUS THAN
THE PREVIOUS DAYS...AT LEAST THROUGH WEDNESDAY NIGHT. EXPECT A LULL
IN RAINFALL ACTIVITY THURSDAY. UPPER LEVEL FLOW FLATTENS ON FRIDAY.
MODELS DEVELOP A DEEP UPPER LEVEL RIDGE THAT SHOULD BRING SUBSIDENCE
AND RELATED WIDESPREAD DRIER CONDITIONS TO THE AREA SATURDAY NIGHT
THROUGH THE BEGINNING OF NEXT WEEK.
WENT WITH WPC FOR TEMPERATURES THROUGH THE PERIOD.
&&
.AVIATION /07Z MONDAY THROUGH FRIDAY/...
06Z MONDAY THRU 06Z TUESDAY...
AN ORGANIZED AREA OF SHOWERS AND STORMS WILL CROSS THE EASTERN
PORTION OF THE AREA 06Z TO 12Z...AFFECTING MAINLY CKB...EKN...AND
BKW.
LOOK FOR MVFR TO IFR IN THE ORGANIZED AREA OF SHOWERS...THEN IFR
CEILINGS AND VSBY DEVELOPING BEHIND THE SHOWERS
OVERNIGHT...AFFECTING ALL MAJOR TERMINALS. A RETURN TO VFR
CONDITIONS BY AROUND 15Z...WITH PERHAPS A BRIEF PERIOD OF MVFR
CIGS IN THE TRANSITION. LOOK FOR ANOTHER ORGANIZED AREA OF
SHRA/TSRA...WITH MVFR TO LOCALLY IFR CONDITIONS...TO RAPIDLY CROSS
THE AREA FROM NORTHWEST TO SOUTHEAST IN THE AFTN AND EVE HRS. SOME
OF THESE WILL BE STRONG TO SVR BUT AT THIS DISTANCE.
AFTER THIS BATCH OF SHOWERS...LOOK FOR IFR TO RETURN IN LOW CLOUDS
AND VSBY AFTER 02Z.
FORECAST CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 00Z TUESDAY...
FORECAST CONFIDENCE:MEDIUM.
ALTERNATE SCENARIOS: EXTENT OF LOW STRATUS AND FG IN QUESTION.
AFTER 06Z TUESDAY...IFR CONDITIONS POSSIBLE IN THUNDERSTORMS EACH
DAY.
&&
WV...NONE.
OH...NONE.
KY...NONE.
VA...NONE.
&&
.RLX WATCHES/WARNINGS/ADVISORIES...
WV...NONE.
OH...NONE.
KY...NONE.
VA...NONE.
&&
$$
SYNOPSIS...KMC/ARJ/26
NEAR TERM...KMC/30
SHORT TERM...26
LONG TERM...JB/ARJ
AVIATION...JMV
AREA FORECAST DISCUSSION
NWS CHARLESTON WV
158 AM EDT MON JUL 13 2015
.SYNOPSIS...
UPPER LEVEL DISTURBANCES WILL CROSS THE AREA IN NORTHWEST FLOW
THRU NEXT WEEK...KEEPING UNSETTLED CONDITIONS IN PLACE. AN UPPER
LEVEL RIDGE MAY DEVELOP BY THE END OF NEXT WEEKEND.
&&
.NEAR TERM /THROUGH TODAY/...
800 PM UPDATE...
INCREASED POPS TONIGHT FROM THE C LOWLANDS AND ESPECIALLY INTO THE
N LOWLANDS/MTNS. A WEAK LOW PRESSURE SYS OVER OH WILL DRIFT SE
INTO THE AREA OVERNIGHT. THIS COMBINED WITH SOME MID LEVEL LIFT
OVER THE AREA SHOULD ALLOW SHRA INCREASE IN COVERAGE THIS AFTER
MIDNIGHT. AS THIS SYS SPIRALS INTO THE AREA...EXPECT LOW CIGS TO
DEVELOP ALONG WITH PATCHY FG.
PREVIOUS DISCUSSION BELOW...
LATEST SATELLITE IMAGERY DEPICTS A RATHER CHAOTIC IMAGE OVER THE
MIDDLE ATLANTIC STATES THIS AFTERNOON...WITH SEVERAL FEATURES OF
NOTE. ACROSS CENTRAL AND EASTERN OHIO THERE IS A FAIRLY WELL
DEFINED SHORTWAVE KICKING OFF SHOWER ACTIVITY ACROSS NORTHEASTERN
OHIO. SKIES HAVE STARTED TO CLEAR SOME ACROSS CENTRAL AND EASTERN
KY...IN THE WAKE OF MCS WHICH MOVED THROUGH THIS MORNING. SEVERAL
OUTFLOW BOUNDARIES CAN BE SEEN IN EASTERN TN AND SOUTHERN KY AS
WELL. THESE HELPING TO KICK OFF CONVECTION. ACROSS WEST VIRGINIA A
SOLID MID DECK OF BLOW CLOUDS HAVE IMPEDED DAYTIME HEATING. THUS
THERE IS A LACK OF CONVECTION INITIATION SO FAR. HOWEVER...BL
HEATING ACROSS THE ELEVATED TERRAIN ALLOWING SOME CU TO FORM.
LATEST SHORT TERM MODELS HAVE BEEN SLOW TO CATCH ON WITH ALL OF
THESE SMALLER SCALE FEATURES. HOWEVER...LATEST RUNS SEEM TO SHOW A
TREND THAT PRECIPITATION SHOULD REMAIN SUPPRESSED FOR THE VERY NEAR
TERM WITH THE RUC AND HRRR IN GENERAL AGREEMENT. AS SHORTWAVE TRACKS
ACROSS THE NORTHERN TIER THIS EVENING...RAMPS POPS BACK UP. FOR
MONDAY...BROAD BUSHED POPS WITH AN EYE ON FEATURES THAT MAY TRACK
ACROSS IN NORTHWEST FLOW.
&&
.SHORT TERM /TONIGHT THROUGH TUESDAY NIGHT/...
THE GFS AND ECMWF MODELS ARE IN BETTER AGREEMENT WITH AN H500
SHORTWAVE UNDER NORTHWEST FLOW CROSSING THE AREA MONDAY NIGHT. THE
NAM LOOKS ABOUT 6-12 HOURS SLOWER BRINGING MOST OF THE ENERGY BY 12Z
TUESDAY. PREFER THE CONSENSUS FROM GFS/ECMWF. THEREFORE...EXPECT
THIS SHORTWAVE TO BRING GOOD CHANCES FOR SHOWERS OR THUNDERSTORMS...
SOME WITH PERIODS OF HEAVY RAIN INTO EARLY TUESDAY.
MODELS ARE IN AGREEMENT WITH A STRONGER TROUGH/LOW PRESSURE SYSTEM
TO DROP FROM THE GREAT LAKES REGION...SOUTHEAST ACROSS PA AND
PORTIONS OF NORTHERN WV TUESDAY NIGHT. ADDITIONAL ROUNDS FOR SHOWERS
AND THUNDERSTORMS WITH HEAVY RAIN WILL BE POSSIBLE. HAVE CODED
LIKELY POPS FOR BOTH DAYS WITH EACH SYSTEM.
CONCERNS FOR FLOODING CONTINUES DURING THIS PERIOD...AND WILL
CONTINUE MENTION IN THE HAZARDOUS WEATHER OUTLOOK. TEMPERATURES WILL
CONTINUE TO BE MODERATE WITH CLOUDS AND SHOWERS...BUT ALSO REMAINING
QUITE HUMID. MINOR CHANGES MADE TO PREVIOUS TEMPERATURES.
&&
.LONG TERM /WEDNESDAY THROUGH SUNDAY/...
FOR WEDNESDAY...THE AREA WILL STILL BE UNDER THE INFLUENCE OF A
BROAD UPPER LEVEL TROUGH AND NORTHWEST FLOW...KEEPING THE AREA UNDER
CHANCES FOR ADDITIONAL SHOWERS AND THUNDERSTORMS LESS NUMEROUS THAN
THE PREVIOUS DAYS...AT LEAST THROUGH WEDNESDAY NIGHT. EXPECT A LULL
IN RAINFALL ACTIVITY THURSDAY. UPPER LEVEL FLOW FLATTENS ON FRIDAY.
MODELS DEVELOP A DEEP UPPER LEVEL RIDGE THAT SHOULD BRING SUBSIDENCE
AND RELATED WIDESPREAD DRIER CONDITIONS TO THE AREA SATURDAY NIGHT
THROUGH THE BEGINNING OF NEXT WEEK.
WENT WITH WPC FOR TEMPERATURES THROUGH THE PERIOD.
&&
.AVIATION /06Z MONDAY THROUGH FRIDAY/...
06Z MONDAY THRU 06Z TUESDAY...
AN ORGANIZED AREA OF SHOWERS AND STORMS WILL CROSS THE EASTERN
PORTION OF THE AREA 06Z TO 12Z...AFFECTING MAINLY CKB...EKN...AND
BKW.
LOOK FOR MVFR TO IFR IN THE ORGANIZED AREA OF SHOWERS...THEN IFR
CEILINGS AND VSBY DEVELOPING BEHIND THE SHOWERS
OVERNIGHT...AFFECTING ALL MAJOR TERMINALS. A RETURN TO VFR
CONDITIONS BY AROUND 15Z...WITH PERHAPS A BRIEF PERIOD OF MVFR
CIGS IN THE TRANSITION. LOOK FOR ANOTHER ORGANIZED AREA OF
SHRA/TSRA...WITH MVFR TO LOCALLY IFR CONDITIONS...TO RAPIDLY CROSS
THE AREA FROM NORTHWEST TO SOUTHEAST IN THE AFTN AND EVE HRS. SOME
OF THESE WILL BE STRONG TO SVR BUT AT THIS DISTANCE.
AFTER THIS BATCH OF SHOWERS...LOOK FOR IFR TO RETURN IN LOW CLOUDS
AND VSBY AFTER 02Z.
FORECAST CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 00Z TUESDAY...
FORECAST CONFIDENCE:MEDIUM.
ALTERNATE SCENARIOS: EXTENT OF LOW STRATUS AND FG IN QUESTION.
AFTER 06Z TUESDAY...IFR CONDITIONS POSSIBLE IN THUNDERSTORMS EACH
DAY.
&&
.RLX WATCHES/WARNINGS/ADVISORIES...
WV...NONE.
OH...NONE.
KY...NONE.
VA...NONE.
&&
$$
SYNOPSIS...KMC/ARJ
NEAR TERM...KMC/30
SHORT TERM...ARJ
LONG TERM...JB/ARJ
AVIATION...JMV
AREA FORECAST DISCUSSION
NWS BLACKSBURG VA
221 AM EDT MON JUL 13 2015
.SYNOPSIS...
A WEAK WARM FRONT WILL LIFT SLOWLY NORTHEAST TOWARD THE REGION
TONIGHT BEFORE PASSING TO THE NORTH LATER MONDAY INTO MONDAY NIGHT.
NORTHWEST FLOW ALOFT WILL ALLOW UPPER LEVEL DISTURBANCES TO SPILL
SOUTHEAST INTO THE AREA ALONG THE BOUNDARY THROUGH TUESDAY
RESULTING IN PERIODIC ROUND OF SHOWERS AND THUNDERSTORMS. A WEAK
COOL FRONT SHOULD DROP THROUGH THE REGION FROM THE NORTH BY MID
WEEK.
&&
.NEAR TERM /THROUGH TODAY/...
AS OF 730 PM EDT SUNDAY...
STILL NO CLEAR MODEL CONSENSUS ON TIMING OR INTENSITY OF
PRECIPITATION...BUT SO FAR TODAY...ONLY RAIN SHOWERS HAVE IMPACTED
THE CWA. A CELL WEST OF TAZEWELL ONGOING CURRENTLY...IS THE FIRST
CELL I HAVE SEEN EVEN NEAR OUR CWA YET TO EXHIBIT ANY LIGHTNING.
MESO-SCALE MODELS HAVE VARYING DEGREES OF CONVECTION IMPACTING THE
AREA OVERNIGHT. THE HRRR BRINGS THE ACTIVITY CURRENTLY IN KENTUCKY
INTO OUR REGION IN A DIMINISHED STATE TOWARD MIDNIGHT. THE LOCAL
WRF KEEPS ALL SIGNIFICANT ACTIVITY WEST OF I-77...DROPPING THE
MOST INTENSE CONVECTION SOUTHWARD THROUGH EASTERN KY/EASTERN TN.
NCEP WRF MODELS IN BETWEEN...BUT AGAIN SHOW NOTHING SIGNIFICANT IN
OUR CWA TODAY OR TOMORROW. HAVE ADJUSTED POPS SOMEWHAT OVERNIGHT
INTO THE EARLY MORNING HOURS TO ACCOUNT FOR BETTER THREAT FOR
CONVECTION WEST OF I-77...LESS LEAST OF THE BLUE RIDGE. ONLY MINOR
ADJUSTMENTS TO T/TD NEEDED AT THIS TIME.
AS OF 355 PM EDT SUNDAY...
MODELS OFFERING SEVERAL DIFFERENT SOLUTIONS FOR TONIGHT AND
MONDAY...ESPECIALLY LOOKING AT WINDS...LOCATION OF PRECIPITATION
AND MAXIMUM TEMPERATURES ON MONDAY.
SATELLITE TOTAL PRECIPITABLE WATER PRODUCT AND VERTICAL PROFILERS
INDICATED PRECIPITABLE WATER VALUES HAVE RISEN TO AROUND 1.5
INCHES. WIDELY SCATTERED SHOWERS AND ISOLATED THUNDERSTORMS HAVE
DEVELOPED ON THE EASTERN EDGE OF A OLD MESOSCALE COMPLEX. SOME
GUIDANCE SUGGESTS THE CHANCE OF PRECIPITATION WILL EXTEND WELL
INTO THE EASTERN COUNTY WARNING AREA TONIGHT.
ANOTHER CLUSTER OF SHOWERS AND THUNDERSTORMS WILL DEVELOP UPSTREAM
TONIGHT WITH MORE PRECIPITATION IN THE FORECAST AREA MONDAY
AFTERNOON. BUT OVERALL INSTABILITY AND SHEAR IS MARGINAL. BELIEVE
BEST PROBABILITY FOR PRECIPITATION AND HIGHEST RAINFALL AMOUNTS
WILL BE ALONG AND WEST OF I-77 THROUGH MONDAY AFTERNOON.
WITH HIGHER SURFACE DEW POINTS BACK IN THE AREA...MINIMUM TEMPERATURES
WILL BE MILDER TONIGHT THAN ON SUNDAY MORNING. THE AMOUNT OF CLOUD
COVER IN THE MORNING AND PRECIPITATION IN THE AFTERNOON WILL
IMPACT THE TEMPERATURES ON MONDAY. STAYED CLOSER TO BIAS CORRECTED
MAV GUIDANCE FOR TONIGHT AND ON MONDAY.
&&
.SHORT TERM /TONIGHT THROUGH WEDNESDAY NIGHT/...
AS OF 230 PM EDT SUNDAY...
WEATHER SCENARIO REMAINS QUITE COMPLICATED WITH TIMING OF FEATURES
ACROSS THE AREA WITHIN A VERY MOIST/UNSTABLE ENVIRONMENT WHILE LIMITED
VIA WESTERLY WINDS ALOFT AND ONLY WEAK SURFACE FEATURES UNTIL LATE
TUESDAY. LATEST SUITE OF SOLUTIONS SUGGEST THAT MAY INIT BETWEEN UPPER
WAVES MONDAY EVENING AS A LEAD SHORTWAVE EXITS THE PIEDMONT AHEAD OF
PERHAPS ANOTHER UPSTREAM VORT/MCS THAT LOOKS TO DIVE SE TOWARD THE
SOUTHERN APPALACHIANS BY EARLY TUESDAY. APPEARS THIS IMPULSE MAY ACT TO
ENHANCE CONVERGENCE ALONG THE WESTERN SLOPES MONDAY EVENING WITH SOME
OF THIS POSSIBLY JETTING ACROSS THE SW OVERNIGHT ALONG THE RETREATING
WARM FRONT. THIS COULD PROVIDE A TIGHT GRADIENT TO POPS WITH LITTLE OUT
EAST AFTER ANY EVENING COVERAGE FADES WITH A COUPLE ROUNDS POSSIBLE OUT
WEST WHERE FOR NOW WILL KEEP OVERALL LIKELY POPS IN PLACE.
STRONG UPPER TROUGH FOR JULY WILL DIG SE OUT OF THE GREAT LAKES TUESDAY
BEFORE SLIDING TO NEAR THE DELMARVA ON WEDNESDAY. THIS WILL PUSH THE
TRAILING SHORTWAVE TROUGH AXIS SE TOWARD THE REGION LATE IN THE DAY
TUESDAY...AIDED BY INCREASING WINDS ALOFT AND HIGH INSTABILITY...
PROVIDED CAN GET ENOUGH HEATING THROUGH RESIDUAL DEBRIS CLOUDS...AND
ISOLATED SHOWERS ESPCLY WEST. HOWEVER GUIDANCE SHOWS A VERY PRONOUNCED
WEST/NW TRAJECTORY JUST ABOVE THE BOUNDARY LAYER WHICH WOULD TEND TO
FOCUS MOST BANDED CONVECTION OVER THE WEST AS THE NW FLOW CONVEYOR BELT
SHOULD BE ABOUT OVERHEAD BY THEN. LEE TROUGH ALSO QUITE STRONG BY LATER
TUESDAY WHICH IN CONJUNCTION WITH A SURFACE LOW FORMING IN RESPONSE TO
THE 5H SYSTEM MAY CAUSE A QUICK JUMP TO THE EAST OF THE AREA LATE IN
THE DAY. SINCE THIS LOOKS QUITE REALISTIC PENDING TIMING...WILL ADJUST
POPS TO HIGHER LIKELYS FAR WEST TUESDAY PER HIGH FORECAST THETA-
E/DIVERGENCE ALOFT...AND GO HIGHER CHANCE EAST WITH LEAST COVERAGE BLUE
RIDGE GIVEN DOWNSLOPE INTO TUESDAY NIGHT. THIS APPEARS TO BE THE PERIOD
FOR MORE WIDESPREAD SEVERE SO KEEPING IN THE HWO PER GOING SPC
OUTLOOKS.
AREA WILL SPILL UNDER THE COLD POOL ALOFT WITH THE 5H LOW TO THE NE ON
WEDNESDAY WITH QUITE A BIT OF SUPPORT ROTATING AROUND THIS FEATURE TO
KEEP DECENT LIFT GOING THROUGH LATE WEDNESDAY. THINK MORE OF A
NORTHERLY TRAJECTORY SHOULD TEND TO LIMIT SHRA ACROSS THE FAR SOUTH BUT
APPEARS COULD SEE MORE WIDESPREAD WEAKER SHRA/ISOLATED TSRA WEDNESDAY
BEFORE DRIER AIR ALOFT ADVECTS IN AND ENDS THE SHOWER THREAT DURING THE
EVENING. OVERALL PLAN TO KEEP POPS ON THE CHANCE SIDE PENDING LATER
RUNS SINCE THE DEGREE OF RESIDUAL MOISTURE RATHER UNCERTAIN FOR NOW.
KEPT TEMPS ON THE WARM SIDE OF MOS INTO TUESDAY NIGHT WITH LOW AND EVEN
MID 90S POSSIBLE EAST TUESDAY IF CLOUDS/SHRA ARE LESS. SHOULD BE A BIT
COOLER UNDER MORE CLOUDS...SHOWERS AND NORTHERLY FLOW WEDNESDAY WITH
MOSTLY 80S EXCEPT PERHAPS ONLY SOME 70S FOR HIGHS WEST.
&&
.LONG TERM /THURSDAY THROUGH SUNDAY/...
AS OF 100 PM EDT SUNDAY...
5H HEIGHTS WILL BUILD EAST ACROSS THE REGION THROUGH MUCH OF THE PERIOD
AS THE LARGE UPPER HIGH OVER THE SOUTHERN PLAINS NUDGES EASTWARD INTO
NEXT WEEKEND. THIS SHOULD MEAN A MORE DIURNALLY DRIVEN LESS ORGANIZED
PATTERN TO CONVECTION AS FOCUS SHIFTS TO MORE OUTFLOW DRIVEN SHRA/TSRA
PERHAPS AIDED BY FAINT SHORTWAVE ENERGY PASSING AROUND THE RIDGE IN THE
WEST/NW FLOW ALOFT. INITIALLY SHOULD BE IN THE WAKE OF THE FRONT TO THE
SOUTH AND THE UPPER SYSTEM TO THE EAST THURSDAY...WITH WEAK HIGH
PRESSURE TO THE NORTH BRINGING A PERIOD OF WEAK SUBSIDENCE THURSDAY
INTO THURSDAY NIGHT INCLUDING ONLY ISOLATED CONVECTION AT BEST.
MOISTURE SHOULD START TO MAKE A SLOW RETURN FRIDAY AND ESPCLY SATURDAY
AS THE WEAK FRONT SHIFTS BACK NORTH AND WEAK RETURN FLOW DEVELOPS. THIS
LOOKS TO BRING SCATTERED NATURE POPS BACK BY FRIDAY AFTERNOON WITH
HIGHER CHANCES SATURDAY UNDER BETTER PWATS. NEXT WEAK UPPER TROUGH AND
ITS ASSOCIATED COOL FRONT APPROACHES ON SUNDAY WHILE PRECEDED BY MORE
WESTERLY FLOW. THIS SUGGESTS BEST CHANCE POPS WEST/NORTH AND LESS OUT
EAST DESPITE DEEP MOISTURE AND GOOD HEATING.
A SLIGHTLY COOLER/DRIER PERIOD THURSDAY/THURSDAY NIGHT LOOKS TO REBOUND
BACK TO HIGHS OF 85-90 WEST AND LOW/MID 90S EAST BY NEXT WEEKEND UNDER
WESTERLY FLOW AND PROGGED 85H TEMPS OF +22-23C.
&&
.AVIATION /06Z MONDAY THROUGH FRIDAY/...
AS OF 200 AM EDT MONDAY...
SHOWERS AND THUNDERSTORMS WILL CONTINUE TO DEVELOP OVER THE AREA
THROUGH DAYBREAK AS W-E NOCTURNAL 85H JET FEEDS UNSTABLE AIR INTO
THE REGION FROM THE OHIO VALLEY. THERE HAS BEEN A CONSIDERABLE
AMOUNT OF LIGHTNING WITH THESE STORMS IN ADDITIONS TO TORRENTIAL
DOWNPOURS WITH IFR VSBYS.
THE 85H JET IS EXPECTED TO WEAKEN AFTER DAYBREAK YIELDING A DEMISE
IN THE SHOWER ACTIVITY BETWEEN 12Z/8AM AND 15Z/11AM. VFR
CONDITIONS ARE EXPECTED TO RETURN AFTER 15Z AND PERSIST THROUGH
THE AFTERNOON.
NEXT OPPORTUNITY FOR SHOWERS/STORMS WITH POTENTIAL TO DISRUPT
AVIATION WILL COME FROM AN ORGANIZED MESOSCALE CONVECTIVE SYSTEM
WHICH IS EXPECTED TO DROP SOUTHEAST FROM THE UPPER MIDWEST
TODAY...CROSSING THE OHIO VALLEY LATE THIS AFTERNOON. THIS FEATURE
WILL LIKELY BE ACCOMPANIED BY SEVERE WEATHER...WITH THE POTENTIAL
TO IMPACT THE CENTRAL APPALACHIANS TOWARD SUNSET. FOR NOW WILL
PLACE VCTS IN THE TAFS BEGINNING 00Z/8PM AND WILL REFINE THE
FORECAST AS RADAR TRENDS DICTATE.
WINDS TODAY ARE EXPECTED TO BE LIGHT AND VARIABLE. THE ONLY
EXCEPTION WILL BE POTENTIAL FOR WIND GUSTS OF 20 KTS VCNTY OF
SHOWERS/STORMS THIS MORNING. THE STORM COMPLEX WHICH IS FORECAST
TO DROP SOUTHEAST THROUGH THE OHIO VALLEY IS EXPECTED TO CONTAIN
SEVERE GUSTS...50 KTS OR MORE. THE STORM PREDICTION CENTER HAS
POSTED A MODERATE RISK FOR SEVERE WEATHER FROM ILLINOIS TO
KENTUCKY.
EXTENDED AVIATION DISCUSSION...
POTENTIAL FOR NUMEROUS SHOWERS/STORMS WILL CONTINUE THROUGH
TUESDAY. AN ACTIVE NORTHWEST/BAROCLINIC FLOW WILL REMAIN IN PLACE
ALONG THE NORTHEAST SIDE OF A STRONG SUBTROPICAL RIDGE OF HIGH
PRESSURE ANCHORED IN THE SOUTHERN PLAINS. ONE OR MORE CONVECTIVE
COMPLEXES APPEAR LIKELY WITHIN THIS TIME FRAME...BUT LOW
CONFIDENCE ON EXACT TIMING ATTM. PLACEMENT FAVORS A TRACK FROM THE
UPPER MIDWEST THROUGH THE LOWER OHIO VALLEY AND INTO THE SOUTHERN
APPALACHIANS.
MORE TYPICAL SUMMERTIME CONDITIONS RETURN FOR THE LATER
HALF OF THE WEEK WITH EARLY MORNING FOG/LOW CLOUDS IN THE USUAL
SPOTS...KLWB/KBCB/KLYH...AND ISOLATED TO SCATTERED AFTERNOON/EVENING
SHOWERS AND THUNDERSTORMS. OVERALL...CIGS AND VSBYS SHOULD BE VFR
MUCH OF THE TIME PERIOD.
&&
.RNK WATCHES/WARNINGS/ADVISORIES...
VA...NONE.
NC...NONE.
WV...NONE.
&&
$$
SYNOPSIS...JH/PM
NEAR TERM...AMS/RAB
SHORT TERM...JH
LONG TERM...JH
AVIATION...PM
AREA FORECAST DISCUSSION
NWS CHEYENNE WY
1120 PM MDT SUN JUL 12 2015
.UPDATE...
ISSUED AT 921 PM MDT SUN JUL 12 2015
REGIONAL RADARS INDICATED THAT THE ISOLATED CONVECTION OVER THE
NORTHEAST CWA DISSIPATED SHORTLY AFTER SUNSET...WITH SKIES BECOMING
MOSTLY CLEAR. LIKEWISE...WIND SPEEDS DIMINISHED AND WILL REMAIN
BETWEEN 10 AND 15 MPH TONIGHT. UPDATED EVENING ZONES HAVE BEEN
DISSEMINATED.
&&
.SHORT TERM...(THIS AFTERNOON THROUGH TUESDAY NIGHT)
ISSUED AT 258 PM MDT SUN JUL 12 2015
LOW-LEVEL CUMULUS CONTINUES TO EXPAND IN BOTH COVERAGE AND VERTICAL
EXTENT THIS AFTERNOON AS CONVECTIVE TEMPERATURES ARE REACHED. RECENT
TRENDS IN RADAR AND VISIBLE SATELLITE IMAGERY HAVE SHOWN DIFFICULTY
FOR CONVECTION TO INITIATE. THIS IS PARTIALLY DUE TO STRONG CAPPING
WITH H7 TEMPS AROUND +14 TO +16 DEG C AND LOW-LEVEL DRYING OWING TO
STRONG MIXING. THE MODELS DO NOT SHOW ANY QPF...AND THE HRRR OFFERS
LITTLE SUPPORT FOR THUNDERSTORMS TODAY. HOWEVER...OPTED TO MAINTAIN
SLIGHT CHANCE POPS THROUGH 00Z GIVEN THE RIGHT REAR QUADRANT OF A
110 KT H25 JET STREAK AND A MID-LEVEL VORT MAX OVERHEAD. SHORTWAVE
RIDGING AND RESULTANT SUBSIDENCE WILL KEEP THINGS DRY FROM TONIGHT
THROUGH MUCH OF THE DAY ON MON.
A WEAK FROPA IS STILL EXPECTED TO OCCUR ACROSS THE FAR NORTH EARLY
IN THE DAY ON MON...BUT THIS WILL HAVE LITTLE IMPACT ON OUR SENSIBLE
WEATHER AS WARM ADVECTION OCCURS BENEATH RIDGING ALOFT. THINK THIS
WILL KEEP CONVECTION SUPPRESSED OUTSIDE OF THE MOUNTAINS UNTIL AROUND
21-00Z. INCREASING MONSOONAL MOISTURE IN THE H7-H3 LAYER AND SEVERAL
DISTURBANCES EMBEDDED WITHIN SOUTHWEST FLOW ALOFT WILL ALLOW SHOWERS
AND THUNDERSTORMS TO DEVELOP EASTWARD ONTO THE PLAINS BY LATE AFTN
OR EARLY EVE. NAM/GFS BUFKIT SOUNDINGS SHOW BIG TIME DIFFERENCES IN
THE INSTABILITY PARAMETERS. THE NAM SHOWS 1500-2000 J/KG OF SBCAPE
OVER CYS ON MON AFTN...WHILE THE GFS SHOWS 200 J/KG AT MOST. 0 TO 6
KM SHEAR IS NOT IMPRESSIVE FROM EITHER MODEL...SO DO NOT EXPECT TO
SEE ANYTHING SEVERE. ANY STORMS THAT DEVELOP WILL HAVE THE POTENTIAL
FOR GUSTY WINDS GIVEN INVERTED-V PROFILES.
MOIST SOUTHWEST FLOW BECOMES BETTER ESTABLISHED ON TUE. THE INCREASE
IN MONSOONAL MOISTURE AND LARGE SCALE FORCING SHOULD PROMOTE FAIRLY
WIDESPREAD SHOWERS AND THUNDERSTORMS ACROSS THE CWA. MAINTAINED AT
LEAST SCATTERED POPS FOR MOST AREAS...HIGHEST IN THE MOUNTAINS. WEAK
FLOW ALOFT SUGGESTS LITTLE CONCERN FOR STRONGER CONVECTION DESPITE
MODERATE INSTABILITY WITH CAPES EXCEEDING 1000 J/KG. THE MODELS SHOW
THE COOLEST TEMPERATURES ALOFT ON TUE...BUT NOT MUCH DIFFERENT THAN
PREVIOUS DAYS. CONTINUED TO TREND COOLER FOR HIGHS GIVEN THAT SHOWER
ACTIVITY AND MID LEVEL CLOUD COVER SHOULD BE MORE WIDESPREAD.
.LONG TERM...(WEDNESDAY THROUGH SUNDAY)
ISSUED AT 258 PM MDT SUN JUL 12 2015
MODELS TRENDING WARMER INTO THE EXTENDED FORECAST PERIOD AS
WESTERLY FLOW ALOFT DEVELOPS OVER SOUTHEAST WYOMING AND
PANHANDLE. TEMPERATURES WILL RISE INTO THE 80S OVER MUCH OF
SOUTHEAST WYOMING FROM MID WEEK INTO THE EARLY WEEKEND WITH SOME
90S INTO THE PLAINS. 90 DEGREE HIGHS LIKELY FOR THE NEBRASKA
PANHANDLE AND WOULD NOT BE SURPRISED TO SEE A SOME 100 DEGREE
READINGS LATE INTO THE WEEK IN PLACES LIKE CHADRON AND SCOTTS
BLUFF. MODELS ALSO TRENDING DRIER THROUGH THIS PERIOD WITH
WESTERLY DOWNSLOPE FLOW BECOMING MORE LIKELY.
NUMERICAL MODELS ARE STRUGGLING TO RESOLVE THE MOVEMENT OF AN
UPPER LEVEL TROUGH OVER THE PACIFIC NORTHWEST LATE IN THE WEEK.
YESTERDAYS EC AND GFS BOTH WERE SHOWING THE TROUGH MOVING ACROSS
THE NORTHERN AND CENTRAL ROCKIES THIS UPCOMING WEEKEND. LAST
NIGHTS EC AND GFS BOTH INDICATED SPLITTING ENERGY WITH A CLOSED
LOW DEVELOPING OVER THE PACIFIC NORTHWEST WITH THE REST OF THE
ENERGY MOVING INTO CENTRAL CANADA. TODAYS MODEL RUNS ARE SOMEWHERE
IN BETWEEN. THE DIFFERENCE BETWEEN THE CLOSED LOW SOLUTION AND THE
PROGRESSIVE SOLUTION IS THE DIFFERENCE BETWEEN COOL AND WET AND
HOT AND DRY RESPECTIVELY. NOT REMOTELY CONFIDENT IN ANY SOLUTION
AT THIS TIME.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH MONDAY AFTERNOON)
VFR CONDITIONS AND LIGHT WINDS ARE EXPECTED FOR THE REST OF TONIGHT
AND INTO MONDAY FOR MOST OF SOUTHEAST WYOMING AND WESTERN NEBRASKA.
KRWL AND KLAR MAY GUST UP TO 20 KNOTS MONDAY AFTERNOON DUE TO LLVL
MIXING. OTHERWISE THUNDERSTORMS ARE EXPECTED TO DEVELOP AROUND THE
MOUNTAINS MONDAY AFTERNOON...MAINLY ALONG AND SOUTH OF I80. ADDED
VCTS FOR KLAR AND KCYS MONDAY AFTERNOON.
&&
.FIRE WEATHER...
ISSUED AT 250 PM MDT SUN JUL 12 2015
WARM AND DRY CONDITIONS WILL CONTINUE THIS AFTERNOON THROUGH MUCH OF
THE DAY ON MON. ELEVATED CONDITIONS ARE OCCURRING OVER EAST CENTRAL
WYOMING WITH HUMIDITIES NEAR 15 PERCENT AND WIND GUSTS TO 25 MPH AT
LUSK...BUT THIS SHOULD IMPROVE SHORTLY. LIGHT WINDS ARE EXPECTED ON
MON WITH MINIMUM HUMIDITIES AROUND 20 PERCENT. THE BEST CHANCE FOR
WETTING RAINS WILL ARRIVE ON TUE WITH SCATTERED TO NUMEROUS SHOWERS
AND THUNDERSTORMS LIKELY ACROSS MUCH OF THE AREA.
&&
.CYS WATCHES/WARNINGS/ADVISORIES...
WY...NONE.
NE...NONE.
&&
$$
UPDATE...MAJ
SHORT TERM...CLH
LONG TERM...SML
AVIATION...TJT
FIRE WEATHER...CLH
AREA FORECAST DISCUSSION
NWS ALBANY NY
1028 AM EDT MON JUL 13 2015
.SYNOPSIS...
HIGH PRESSURE OVER THE REGION WILL WEAKEN TODAY AS A DISTURBANCE
IN THE UPPER LEVELS OF THE ATMOSPHERE APPROACHES FROM THE GREAT
LAKES. AS A RESULT...THERE IS A CHANCE OF SHOWERS AND
THUNDERSTORMS THIS AFTERNOON INTO THE EARLY EVENING. THE CHANCE
FOR SHOWERS AND STORMS CONTINUES TUESDAY THROUGH WEDNESDAY AS A
COLD FRONT APPROACHES FROM THE NORTHWEST AND CROSSES THE AREA.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
BAND OF CLOUDINESS ACROSS THE CENTRAL PART OF THE FORECAST AREA
ASSOCIATED WITH UPPER LEVEL TROUGH. REST OF AREA GENERALLY SUNNY.
ADJUSTED CLOUD COVER TO BE IN LINE WITH CURRENT SATELLITE IMAGE.
CLOUDS WILL INCREASE ACROSS THE FORECAST AREA AS HAZY...HOT AND
HUMID CONDITIONS WILL DEVELOP.
CURRENT TEMPERATURES IN 70S TO NEAR 80 DEGREES. WINDS ARE LIGHT
AND FROM THE SOUTHEAST. MODELS INDICATE WINDS WILL INCREASE FROM
THE SOUTH-SOUTHEAST LATER TODAY AND BECOME BREEZY.
LATEST HRRR SHOWS SCATTERED SHOWERS AND THUNDERSTORMS DEVELOPING
AFTER NOON WITH GREATEST COVERAGE ACROSS THE TACONICS...SOUTHERN
VERMONT...BERKSHIRE COUNTY MA AND THE CATSKILLS. ALSO A FEW
ISOLATED CELLS EXPECTED OVER THE ADIRONDACKS THIS AFTERNOON.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH WEDNESDAY NIGHT/...
THE UPPER LEVEL DISTURBANCE WILL PASS TO OUR SOUTH AND WEST
TUESDAY NIGHT INTO WEDNESDAY. GUIDANCE KEEPS THE UPPER LEVEL
TROUGH POSITIVELY TILTED AND PROGRESSIVE. A COLD FRONT WILL ALSO
APPROACH AND IS EXPECTED TO CROSS THE REGION WEDNESDAY AFTERNOON
AND NIGHT. THIS WILL RESULT IN CHANCES STORMS TUESDAY THROUGH
WEDNESDAY. NO STRONG FORCING WILL BE PRESENT SO STORMS ARE NOT
EXPECTED TO BE STRONG OR SEVERE. THE STORM PREDICTION CENTER ONLY
HAS THE LOCAL AREA UNDER A GENERAL THUNDERSTORMS OUTLOOK.
GUIDANCE DOES INDICATE PWATS VALUES WILL RISE TO 1.5+ INCHES
TUESDAY NIGHT INTO WEDNESDAY AHEAD OF THE COLD FRONT...SO STORMS
WILL BE CAPABLE OF PRODUCING HEAVY DOWNPOURS WHICH COULD CAUSE
SOME URBAN AND POOR DRAINAGE FLOODING. WILL CONTINUE TO H8IGHLIGHT
THIS IN OUR HAZARDOUS WEATHER OUTLOOK.
SEASONABLY WARM TEMPERATURES ARE EXPECTED BOTH TUESDAY AND
WEDNESDAY. TUESDAY NIGHT WILL BE A MILD AND MUGGY NIGHT. HOWEVER
WITH THE PASSAGE OF THE COLD FRONT DRIER AIR WILL BE FILTERED IN
ON A NORTHERLY FLOW FOR WEDNESDAY NIGHT.
&&
.LONG TERM /THURSDAY THROUGH SUNDAY/...
HIGH PRESSURE WILL BE SITUATED OVER THE REGION TO START THE LONG
TERM PERIOD FOR THURSDAY INTO FRIDAY. SKIES WILL BE PARTLY TO MOSTLY
CLEAR WITH NO PRECIP EXPECTED. HIGHS LOOK TO BE IN THE LOW TO MID
80S FOR VALLEY AREAS...AND LOWS WILL BE IN THE 50S FOR THURSDAY
NIGHT...AND 60S FOR FRIDAY NIGHT.
WITH STRONG RIDGING ESTABLISHING ITSELF OVER THE CENTRAL US...THE
NORTHEAST WILL BE SITUATED WITHIN NORTHWEST FLOW ALOFT. THIS WILL
ALLOW A SERIES OF WEAK UPPER LEVEL DISTURBANCES TO MOVE TOWARDS THE
REGION FROM SOUTHERN CANADA. THE TIMING OF THESE SUBTLE FEATURES IS
STILL UNKNOWN...BUT EACH DISTURBANCE WILL ALLOW A CHANCE FOR SOME
SCATTERED SHOWERS AND THUNDERSTORMS...ESP WITHIN PEAK DAYTIME
HEATING OF AFTN INTO THE EARLY EVENING HOURS. POPS START TO RISE
FOR LATE FRIDAY NIGHT...AND WILL ALLOW FOR CHC POPS ON BOTH
SAT/SUNDAY. IT LOOKS LIKE THESE CONDITIONS WILL CONTINUE INTO
EARLY NEXT WEEK AS WELL. IT WON/T BE A WASHOUT BY ANY MEANS...BUT
CAN/T RULE OUT THESE SHOWERS AND THUNDERSTORMS THANKS TO THE
PASSING SHORTWAVE ALOFT.
MAX TEMPS OVER THE WEEKEND WILL GENERALLY BE IN THE MID 80S...WITH
MID 60S FOR LOW TEMPS. IT WILL BE FAIRLY MUGGY AS WELL...WITH
DEWPOINTS WELL INTO THE 60S.
&&
.AVIATION /14Z MONDAY THROUGH FRIDAY/...
SOME RADIATIONAL FOG DEVELOPED OVERNIGHT AT KGFL/KPSF...BUT THIS
WILL BE DISSIPATING QUICKLY THANKS TO THE ONSET OF DAYTIME
HEATING/MIXING. ANY LOWER VSBYS/CIGS SHOULD BE GONE WITHIN THE NEXT
HOUR OR SO...ALLOWING FOR VFR CONDITIONS TO RETURN FOR ALL SITES
FOR THE MORNING HOURS.
AN UPPER LEVEL DISTURBANCE IS APPROACHING THE REGION FROM THE
EASTERN GREAT LAKES. SCT-BKN CLOUDS ARE STREAMING AHEAD OF THIS
SYSTEM...MOSTLY HIGH CIRROSTRATUS CLOUDS AROUND 25 KFT. THROUGH THE
MORNING HOURS THERE WILL BE SOME HIGH CLOUDS AROUND...WITH A LIGHT
S-SE SFC WIND DEVELOPING AROUND 5 KTS.
SOME BREAKS IN THE HIGH CLOUDS DURING THE AFTN HOURS MAY ALLOW FOR
SOME CU TO DEVELOP AND PERHAPS EVEN A FEW SPOTTY SHOWERS...MAINLY
OVER THE HIGHER ELEVATIONS. WILL INCLUDE A VCSH FOR ALL TERMINALS TO
ACCOUNT THIS LOW PROBABILITY OF A SHOWER. CANNOT EVEN RULE OUT SOME
THUNDER...BUT CONFIDENCE IS TOO LOW TO INCLUDE AT THIS TAF ISSUANCE.
SHOWERS WILL DISSIPATE BY EVENING WITH THE LOSS OF DAYTIME HEATING.
WITH THE UPPER LEVEL DISTURBANCE NEARBY...MORE SCT-BKN HIGH CLOUDS
ARE EXPECTED FOR TONIGHT WITH NEARLY CALM SFC WINDS ONCE AGAIN. IF
ENOUGH BREAKS IN THE HIGH CLOUDS OCCUR...SOME RADIATIONAL FOG WILL
BE POSSIBLE FOR KGFL/KPSF...WITH AT LEAST MVFR CIGS/VSBYS POSSIBLE.
OUTLOOK...
TUESDAY NIGHT THROUGH WEDNESDAY: MODERATE OPERATIONAL IMPACT. CHANCE
OF SHRA...TSRA.
WEDNESDAY NIGHT THROUGH FRIDAY: NO OPERATIONAL IMPACT. NO SIG WX.
FRIDAY NIGHT THROUGH SATURDAY: MODERATE OPERATIONAL IMPACT. CHANCE OF
SHRA...TSRA.
&&
.FIRE WEATHER...
HIGH PRESSURE OVER THE REGION WILL WEAKEN TODAY AS A DISTURBANCE
IN THE UPPER LEVELS OF THE ATMOSPHERE APPROACHES FROM THE GREAT
LAKES REGION. AS A RESULT WILL BE CHANCES FOR SHOWERS AND
THUNDERSTORMS THIS AFTERNOON INTO THE EARLY EVENING. WE WILL
HAVE CHANCES FOR STORMS TUESDAY THROUGH WEDNESDAY AS A COLD
FRONT ALSO APPROACHES AND CROSSES THE AREA.
&&
.HYDROLOGY...
THERE ARE CHANCES FOR SHOWERS AND THUNDERSTORMS THIS AFTERNOON
INTO EARLY EVENING AS AN UPPER LEVEL DISTURBANCE APPROACHES FROM
THE GREAT LAKES REGION TODAY. THE DISTURBANCE WILL PASS TO OUR
SOUTH AND WEST TUESDAY NIGHT INTO WEDNESDAY AND A COLD FRONT WILL
APPROACH AND CROSS THE REGION RESULTING IN CHANCES STORMS TUESDAY
THROUGH WEDNESDAY. MODELS INDICATE PWATS VALUES WILL RISE TO 1.5+
INCHES TUESDAY NIGHT INTO WEDNESDAY AHEAD OF THE COLD FRONT...SO
STORMS WILL BE CAPABLE OF PRODUCING HEAVY DOWNPOURS WHICH COULD
CAUSE SOME URBAN AND POOR DRAINAGE FLOODING.
MAINLY DRY WEATHER IS EXPECTED THURSDAY AND FRIDAY WITH OUR NEXT
CHANCES FOR STORMS COMING OVER THE WEEKEND AS A SERIES OF WEAK
UPPER LEVEL DISTURBANCES APPROACH AND CROSS THE REGION.
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...IAA
NEAR TERM...IAA/SND
SHORT TERM...IAA
LONG TERM...FRUGIS
AVIATION...SND/FRUGIS
FIRE WEATHER...IAA
HYDROLOGY...IAA
AREA FORECAST DISCUSSION
NWS CHARLESTON SC
1036 AM EDT MON JUL 13 2015
.SYNOPSIS...
AN INLAND TROUGH OF LOW PRESSURE WILL PERSIST THROUGH TUESDAY BEFORE
A WEAK COLD FRONT MOVES INTO THE AREA ON WEDNESDAY. THE FRONT WILL
STALL OVER AREA THROUGH THE END OF THE WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
MADE A QUICK UPDATE TO ACCOUNT FOR THE SHOWERS WHICH RECENTLY
DEVELOPED ALONG THE OLD CONVERGENCE LINE. DUE TO THE THICKER CLOUD
COVER...I ALSO NUDGED DOWN THE MAX TEMPS A DEGREE OR TWO.
12Z SOUNDING FROM CHS SHOWS A MOISTENING OF THE COLUMN BETWEEN 800
AND 600 MB COMPARED TO LAST NIGHT...LIKELY DUE TO SOME MOISTURE
DEBRIS FROM UPSTREAM CONVECTION BEING ADVECTED INTO THE TRI COUNTY
AREA. THIS CAN ALSO BE SEEN ON A LOOP OF THE GOES 7.4 UM SOUNDER
IMAGERY.
THE IMAGERY LOOP ALSO SHOWS SOME DRIER AIR AT MID LEVELS DUE TO
MOVE INTO THE AREA ALONG AND SOUTHWEST OF THE SAVANNAH RIVER
VALLEY...INDICATING THOSE AREAS WILL BECOME MORE UNSTABLE BY
AFTERNOON...HENCE SEE A SLIGHTLY BETTER CHANCE OF CONVECTION
BECOMING SEVERE. THE LATEST HRRR SEEMS TO HAVE AT LEAST A HINT
THAT THIS IS GOING ON AND HITS THE CONVECTION HARDER IN THOSE
AREAS AS WELL. STILL DOES NOT LOOK LIKE ANY KIND OF ORGANIZED
SYSTEM TODAY WITH BULK SHEAR STILL QUITE WEAK...BUT THE SURFACE
CONVERGENCE FROM THE INLAND TROF...AS WELL AS THE WESTWARD MOVING
SEA BREEZE LATER IN THE DAY...WILL KICK OFF SCATTERED CONVECTION
THIS AFTERNOON. THE CONVECTION WILL THEN LIKELY FOLLOW THE
BOUNDARIES AS THEY PROPAGATE OUTWARD FROM THE INITIAL CONVECTION.
FOR TEMPERATURES...I HAVE NOT MADE MUCH CHANGE YET...BUT MID CLOUD
DECK MOVING IN FROM THE NORTHWEST COULD PUT A CAP ON THE MAX TEMPS
TODAY AND MAY REQUIRE A SLIGHT ADJUSTMENT DOWNWARD WITH THE EARLY
AFTERNOON UPDATE.
TONIGHT...THE MODELS ARE AGAIN PROVIDING US WITH MIXED SIGNALS AS TO
WHETHER OR NOT AN MCS WILL FORM EITHER UPSTREAM OR OVER THE LOCAL
AREA. THERE IS LARGE SCALE SUPPORT FOR FORCING PROVIDED BY THE
CONTINUED LEADING EDGE OF THE UPPER JET AND POSSIBLY ANOTHER
SHORT WAVE THAT ARRIVES WITHIN THE PROBLEMATIC NW FLOW ALOFT.
SINCE THE HIGH-RES MODELS AND ECMWF ARE NOT INDICATING ANY MCS
DEVELOPING...OUR FORECAST WILL BE MORE CONSERVATIVE AND SHOW ONLY
ISOLATED TO SCATTERED POPS AND NOT INDICATIVE OF ANY ORGANIZED
SYSTEM AT THIS TIME. TEMPS WILL BE SLIGHTLY ABOVE MID-JULY NORMS
WITH ENOUGH MIXING TO PERSIST THROUGH MUCH OF THE NIGHT.
&&
.SHORT TERM /TUESDAY THROUGH THURSDAY/...
TUESDAY...A NORTHWEST FLOW WILL HELP DIG A MID LVL TROUGH OF LOW
PRESSURE OVER THE NORTHEAST AND MID ATLANTIC STATES. AT THE SFC...AN
AREA OF LOW PRESSURE WILL BEGIN TO SHIFT TOWARD THE NORTHEASTERN
STATES...HELPING ENHANCE A PIEDMONT TROUGH TO ITS SOUTH/SOUTHWEST.
STRONG SFC HEATING AS WELL AS DEEPENING MOISTURE TO THE EAST OF THE
PIEDMONT TROUGH SHOULD FAVOR SCATTERED SHOWERS AND THUNDERSTORMS
DURING AFTERNOON AND EVENING HOURS...PARTICULARLY WHEN AN H5
SHORTWAVE SHIFTS OVER THE REGION AND A SEABREEZE SHIFTS INLAND.
THERE WILL BE A RISK OF SEVERE WEATHER LATE AFTERNOON INTO EARLY
OVERNIGHT HOURS...WITH THE PRIMARY RISKS BEING DAMAGING WINDS AND
HAIL. STRONGEST ACTIVITY IS FAVORED WHERE LOW LVL WIND FIELDS BECOME
ENHANCED...MAINLY IN SOUTHEAST SOUTH CAROLINA. A FEW STORMS COULD
LINGER INTO THE OVERNIGHT PERIOD...BUT THE GENERAL CONSENSUS IS THAT
COVERAGE AND STRENGTH OF STORMS SHOULD DECREASE WITH THE LOSS OF
DAYTIME HEATING. OVERALL HIGHS WILL RANGE IN THE LOW TO MID 90S.
LOWS SHOULD BE IN THE MID/UPPER 70S.
WEDNESDAY...A LARGE SFC LOW WILL BEGIN TO SHIFT OFF THE MID ATLANTIC
COAST WITH A WEAK COLD FRONT EXTENDING TO THE SOUTH/SOUTHWEST.
ALOFT...A STRONGER H5 SHORTWAVE WILL SHIFT OVER THE SOUTHEASTERN
UNITED STATES WITHIN A NORTHWEST FLOW WHILE A 30-35 KT LOW LVL JET
EXTENDS WEST/EAST ACROSS MUCH OF THE AREA. GIVEN THE POSITION OF THE
MOST SUBSTANTIAL FORCING ASSOCIATED WITH THE H5 SHORTWAVE AND THE
LIKELIHOOD OF CONVECTION DEVELOPING SOUTH AND EAST OF THE WEAK COLD
FRONT...SHOWER AND THUNDERSTORM COVERAGE APPEAR GREATEST NEAR
COASTAL AREAS IN SOUTHEAST SOUTH CAROLINA AND IN MOST AREAS OF
SOUTHEAST GEORGIA. SOME THUNDERSTORMS COULD BE STRONG AND/OR SEVERE
DURING THE AFTERNOON/EVENING...WITH DAMAGING WINDS AND HAIL BEING
THE PRIMARY CONCERN. HIGH TEMPS WILL BE DEPENDENT ON CLOUD COVER
PRECIP COVERAGE...BUT SHOULD PEAK BETWEEN THE LOW TO MID 90S OVER
MOST AREAS.
THURSDAY...THE BULK OF H5 SHORTWAVE ACTIVITY WILL BE OFF THE MID
ATLANTIC COAST AS WELL AS THE PRIMARY AREA OF LOW PRESSURE AT THE
SFC. HOWEVER...A WEAK AREA OF LOW PRESSURE WILL REMAIN OVER MUCH OF
THE SOUTHEAST NEAR THE VICINITY OF A STALLED AND/OR DISSIPATING
FRONT. SFC HEATING AND MOISTURE LEVELS NEAR THE WEAK LOW SHOULD
SUPPORT CHANCES OF SHOWERS/THUNDERSTORMS OVER MOST AREAS.
HOWEVER...THE THREAT OF STRONGER THUNDERSTORMS WILL BE LOWER THAN
PREVIOUS DAYS. OVERALL...HIGH TEMPS SHOULD RANGE IN THE LOW TO MID
90S.
&&
.LONG TERM /THURSDAY NIGHT THROUGH SUNDAY/...
CHANCES OF SHOWERS AND THUNDERSTORMS WILL REMAIN IN THE FORECAST
EACH DAY AS A SFC TROUGH OF LOW PRESSURE REDEVELOPS INLAND LATE
WEEK. HOWEVER...COVERAGE COULD BE SLIGHTLY MORE LIMITED ON FRIDAY AS
A LARGE RIDGE OF HIGH PRESSURE NUDGES EASTWARD OVER THE AREA.
GREATER PRECIP CHANCES SHOULD RETURN OVER THE WEEKEND AS THE DEEP
LAYERED RIDGE RETROGRADES WESTWARD IN RESPONSE TO MID LVL TROUGHING
OVER THE EASTERN CONUS. MODELS HINT AT AN UPPER LVL LOW BECOMING
CENTERED OVER THE SOUTHEASTERN UNITED STATES LATE WEEKEND INTO EARLY
NEXT WEEK...PRODUCING ADDITIONAL CHANCES OF SHOWERS AND
THUNDERSTORMS EACH DAY. OVERALL...HIGH TEMPS SHOULD RANGE IN THE LOW
TO MID 90S THROUGH LATE WEEK...THEN POSSIBLY BECOME A FEW DEGREES
COOLER AS THE MID/UPPER LVL LOW BECOMES POSITIONED OVER THE AREA
EARLY NEXT WEEK.
&&
.AVIATION /15Z MONDAY THROUGH FRIDAY/...
PREVAILING VFR THROUGH 12Z TUESDAY. OUR NEXT CHANCE OF
CONVECTION AT THE AIRFIELDS WILL ARRIVE DURING THE AFTERNOON IN
RESPONSE TO THE SEA BREEZE...VARIOUS BOUNDARIES AND SOME ENERGY
ALOFT. PROBABILITIES ARE STILL NOT SUFFICIENT ENOUGH TO SHOW WITH
THE 12Z TAFS...SINCE MODEL CONSENSUS IS POOR. THERE IS THEN THE
RISK OF A CLUSTER OF ORGANIZED CONVECTION /AN MCS/ THAT COULD
APPROACH FROM THE NORTH/NW TONIGHT. BUT AGAIN THE MODEL CONSENSUS
IS LACKING. HOWEVER...SHOULD ANY CONVECTION DIRECTLY IMPACT THE
TERMINALS...EITHER THIS AFTERNOON OR TONIGHT...THEN THEN PERIODIC
FLIGHT RESTRICTIONS WOULD OCCUR.
EXTENDED AVIATION OUTLOOK...VFR CONDITIONS SHOULD GENERALLY PREVAIL
THROUGH LATE WEEK...BUT FLIGHT RESTRICTIONS WILL BE POSSIBLE WITH
SHOWERS AND/OR THUNDERSTORMS...ESPECIALLY TUESDAY AFTERNOON THROUGH
WEDNESDAY EVENING.
&&
.MARINE...
TODAY...CURRENT MARINE OBSERVATIONS SHOW FORECAST IS ON TRACK. A
RECOGNIZABLE SYNOPTIC PATTERN WILL AGAIN PREVAIL...SIMILAR TO WHAT
WE HAVE SEEN MUCH OF THE PAST SEVERAL WEEKS. A NE-SW ALIGNED
PIEDMONT TROUGH AND SUB- TROPICAL ATLANTIC RIDGING ACROSS FLORIDA.
THIS PROVIDES THE REGION WITH A SW FLOW THIS MORNING...BEFORE
WINDS BACK TO THE SOUTH WITH SEA BREEZE INFLUENCES THIS AFTERNOON.
WINDS WILL HOLD AT OR BELOW 10 OR 12 KT THIS MORNING...THEN RISE
UP TO 12- 16 KT THIS AFTERNOON...GREATEST IN CHARLESTON HARBOR
AND THE CHARLESTON COUNTY ATLANTIC WATERS. OF COURSE SHOULD
CONVECTIVE CLOUDINESS INCREASE IN GREATER COVERAGE...THEN THIS
FORECAST MIGHT BE A BIT ON THE HIGH SIDE. BUT BASED ON THESE WINDS
WE LOOK FOR SEA NO MORE THAN 2 OR 3 FT.
TONIGHT...OUR FORECAST IS BASED ON A SCENARIO OF INLAND TROUGH AND
RIDGING TO THE SOUTH/SE...WITH DECENT NOCTURNAL JETTING INFLUENCES TO
BOOST SOUTH/SW WINDS UP TO 15-20 KT AND GUSTY. WE MIGHT EVEN FLIRT
WITH MARGINAL SCA/S OVER OUR AMZ350 AS A RESULT. HOWEVER...SHOULD
ANY CONVECTIVE COMPLEXES DEVELOP OVER OR NEAR THE AREA THEN ALL
BETS ARE OFF...AS CONVECTION WILL STRONGLY IMPACT THESE EXPECTED
SYNOPTIC WINDS.
TUESDAY THROUGH SATURDAY...THE COASTAL WATERS WILL REMAIN SITUATED
BETWEEN HIGH PRESSURE OVER THE WESTERN ATLANTIC AND A TROUGH OF LOW
PRESSURE INLAND TO START OFF THE WEEK. A WEAK COLD FRONT COULD SHIFT
OVER THE WATERS WEDNESDAY...WITH SOME STRONGER THUNDERSTORMS AHEAD
OF IT STARTING TUESDAY NIGHT. MARGINAL SMALL CRAFT ADVISORY LEVEL
CONDITIONS WILL ALSO BE POSSIBLE AS THE PRESSURE GRADIENT TIGHTENS
AHEAD OF THE APPROACHING FRONT...STARTING TUESDAY AFTERNOON AND
PERSISTING INTO WEDNESDAY NIGHT. WEAK LOW PRESSURE SHOULD THEN
SETTLE OVER THE WATERS INTO LATE WEEK.
IN GENERAL...SOUTH/SOUTHWEST WINDS WILL INCREASE TO 15-20 KTS WITH
GUSTS AROUND 25 KTS TUESDAY AFTERNOON INTO WEDNESDAY NIGHT. WINDS
SHOULD THEN IMPROVE LATE WEEK AND BECOME MORE ONSHORE AS WEAK LOW
PRESSURE REMAINS CENTERED INLAND. SEAS WILL RANGE BETWEEN 2-4 FT
EARLY ON TUESDAY...THEN GRADUALLY BUILD TO 3-5 FT MID WEEK. WE COULD
SEE 6 FT SEAS IN OUTER GEORGIA WATERS MID WEEK. SEAS SHOULD THEN
SUBSIDE LATE WEEK.
&&
.CHS WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
SC...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...
NEAR TERM...FWA
SHORT TERM...
LONG TERM...
AVIATION...
MARINE...
AREA FORECAST DISCUSSION
NWS CHARLESTON SC
959 AM EDT MON JUL 13 2015
.SYNOPSIS...
AN INLAND TROUGH OF LOW PRESSURE WILL PERSIST THROUGH TUESDAY BEFORE
A WEAK COLD FRONT MOVES INTO THE AREA ON WEDNESDAY. THE FRONT WILL
STALL OVER AREA THROUGH THE END OF THE WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
12Z SOUNDING FROM CHS SHOWS A MOISTENING OF THE COLUMN BETWEEN 800
AND 600 MB COMPARED TO LAST NIGHT...LIKELY DUE TO SOME MOISTURE
DEBRIS FROM UPSTREAM CONVECTION BEING ADVECTED INTO THE TRI COUNTY
AREA. THIS CAN ALSO BE SEEN ON A LOOP OF THE GOES 7.4 UM SOUNDER
IMAGERY.
THE IMAGERY LOOP ALSO SHOWS SOME DRIER AIR AT MID LEVELS DUE TO
MOVE INTO THE AREA ALONG AND SOUTHWEST OF THE SAVANNAH RIVER
VALLEY...INDICATING THOSE AREAS WILL BECOME MORE UNSTABLE BY
AFTERNOON...HENCE SEE A SLIGHTLY BETTER CHANCE OF CONVECTION
BECOMING SEVERE. THE LATEST HRRR SEEMS TO HAVE AT LEAST A HINT
THAT THIS IS GOING ON AND HITS THE CONVECTION HARDER IN THOSE
AREAS AS WELL. STILL DOES NOT LOOK LIKE ANY KIND OF ORGANIZED
SYSTEM TODAY WITH BULK SHEAR STILL QUITE WEAK...BUT THE SURFACE
CONVERGENCE FROM THE INLAND TROF...AS WELL AS THE WESTWARD MOVING
SEA BREEZE LATER IN THE DAY...WILL KICK OFF SCATTERED CONVECTION
THIS AFTERNOON. THE CONVECTION WILL THEN LIKELY FOLLOW THE
BOUNDARIES AS THEY PROPAGATE OUTWARD FROM THE INITIAL CONVECTION.
FOR TEMPERATURES...I HAVE NOT MADE MUCH CHANGE YET...BUT MID CLOUD
DECK MOVING IN FROM THE NORTHWEST COULD PUT A CAP ON THE MAX TEMPS
TODAY AND MAY REQUIRE A SLIGHT ADJUSTMENT DOWNWARD WITH THE EARLY
AFTERNOON UPDATE.
TONIGHT...THE MODELS ARE AGAIN PROVIDING US WITH MIXED SIGNALS AS TO
WHETHER OR NOT AN MCS WILL FORM EITHER UPSTREAM OR OVER THE LOCAL
AREA. THERE IS LARGE SCALE SUPPORT FOR FORCING PROVIDED BY THE
CONTINUED LEADING EDGE OF THE UPPER JET AND POSSIBLY ANOTHER
SHORT WAVE THAT ARRIVES WITHIN THE PROBLEMATIC NW FLOW ALOFT.
SINCE THE HIGH-RES MODELS AND ECMWF ARE NOT INDICATING ANY MCS
DEVELOPING...OUR FORECAST WILL BE MORE CONSERVATIVE AND SHOW ONLY
ISOLATED TO SCATTERED POPS AND NOT INDICATIVE OF ANY ORGANIZED
SYSTEM AT THIS TIME. TEMPS WILL BE SLIGHTLY ABOVE MID-JULY NORMS
WITH ENOUGH MIXING TO PERSIST THROUGH MUCH OF THE NIGHT.
&&
.SHORT TERM /TUESDAY THROUGH THURSDAY/...
TUESDAY...A NORTHWEST FLOW WILL HELP DIG A MID LVL TROUGH OF LOW
PRESSURE OVER THE NORTHEAST AND MID ATLANTIC STATES. AT THE SFC...AN
AREA OF LOW PRESSURE WILL BEGIN TO SHIFT TOWARD THE NORTHEASTERN
STATES...HELPING ENHANCE A PIEDMONT TROUGH TO ITS SOUTH/SOUTHWEST.
STRONG SFC HEATING AS WELL AS DEEPENING MOISTURE TO THE EAST OF THE
PIEDMONT TROUGH SHOULD FAVOR SCATTERED SHOWERS AND THUNDERSTORMS
DURING AFTERNOON AND EVENING HOURS...PARTICULARLY WHEN AN H5
SHORTWAVE SHIFTS OVER THE REGION AND A SEABREEZE SHIFTS INLAND.
THERE WILL BE A RISK OF SEVERE WEATHER LATE AFTERNOON INTO EARLY
OVERNIGHT HOURS...WITH THE PRIMARY RISKS BEING DAMAGING WINDS AND
HAIL. STRONGEST ACTIVITY IS FAVORED WHERE LOW LVL WIND FIELDS BECOME
ENHANCED...MAINLY IN SOUTHEAST SOUTH CAROLINA. A FEW STORMS COULD
LINGER INTO THE OVERNIGHT PERIOD...BUT THE GENERAL CONSENSUS IS THAT
COVERAGE AND STRENGTH OF STORMS SHOULD DECREASE WITH THE LOSS OF
DAYTIME HEATING. OVERALL HIGHS WILL RANGE IN THE LOW TO MID 90S.
LOWS SHOULD BE IN THE MID/UPPER 70S.
WEDNESDAY...A LARGE SFC LOW WILL BEGIN TO SHIFT OFF THE MID ATLANTIC
COAST WITH A WEAK COLD FRONT EXTENDING TO THE SOUTH/SOUTHWEST.
ALOFT...A STRONGER H5 SHORTWAVE WILL SHIFT OVER THE SOUTHEASTERN
UNITED STATES WITHIN A NORTHWEST FLOW WHILE A 30-35 KT LOW LVL JET
EXTENDS WEST/EAST ACROSS MUCH OF THE AREA. GIVEN THE POSITION OF THE
MOST SUBSTANTIAL FORCING ASSOCIATED WITH THE H5 SHORTWAVE AND THE
LIKELIHOOD OF CONVECTION DEVELOPING SOUTH AND EAST OF THE WEAK COLD
FRONT...SHOWER AND THUNDERSTORM COVERAGE APPEAR GREATEST NEAR
COASTAL AREAS IN SOUTHEAST SOUTH CAROLINA AND IN MOST AREAS OF
SOUTHEAST GEORGIA. SOME THUNDERSTORMS COULD BE STRONG AND/OR SEVERE
DURING THE AFTERNOON/EVENING...WITH DAMAGING WINDS AND HAIL BEING
THE PRIMARY CONCERN. HIGH TEMPS WILL BE DEPENDENT ON CLOUD COVER
PRECIP COVERAGE...BUT SHOULD PEAK BETWEEN THE LOW TO MID 90S OVER
MOST AREAS.
THURSDAY...THE BULK OF H5 SHORTWAVE ACTIVITY WILL BE OFF THE MID
ATLANTIC COAST AS WELL AS THE PRIMARY AREA OF LOW PRESSURE AT THE
SFC. HOWEVER...A WEAK AREA OF LOW PRESSURE WILL REMAIN OVER MUCH OF
THE SOUTHEAST NEAR THE VICINITY OF A STALLED AND/OR DISSIPATING
FRONT. SFC HEATING AND MOISTURE LEVELS NEAR THE WEAK LOW SHOULD
SUPPORT CHANCES OF SHOWERS/THUNDERSTORMS OVER MOST AREAS.
HOWEVER...THE THREAT OF STRONGER THUNDERSTORMS WILL BE LOWER THAN
PREVIOUS DAYS. OVERALL...HIGH TEMPS SHOULD RANGE IN THE LOW TO MID
90S.
&&
.LONG TERM /THURSDAY NIGHT THROUGH SUNDAY/...
CHANCES OF SHOWERS AND THUNDERSTORMS WILL REMAIN IN THE FORECAST
EACH DAY AS A SFC TROUGH OF LOW PRESSURE REDEVELOPS INLAND LATE
WEEK. HOWEVER...COVERAGE COULD BE SLIGHTLY MORE LIMITED ON FRIDAY AS
A LARGE RIDGE OF HIGH PRESSURE NUDGES EASTWARD OVER THE AREA.
GREATER PRECIP CHANCES SHOULD RETURN OVER THE WEEKEND AS THE DEEP
LAYERED RIDGE RETROGRADES WESTWARD IN RESPONSE TO MID LVL TROUGHING
OVER THE EASTERN CONUS. MODELS HINT AT AN UPPER LVL LOW BECOMING
CENTERED OVER THE SOUTHEASTERN UNITED STATES LATE WEEKEND INTO EARLY
NEXT WEEK...PRODUCING ADDITIONAL CHANCES OF SHOWERS AND
THUNDERSTORMS EACH DAY. OVERALL...HIGH TEMPS SHOULD RANGE IN THE LOW
TO MID 90S THROUGH LATE WEEK...THEN POSSIBLY BECOME A FEW DEGREES
COOLER AS THE MID/UPPER LVL LOW BECOMES POSITIONED OVER THE AREA
EARLY NEXT WEEK.
&&
.AVIATION /14Z MONDAY THROUGH FRIDAY/...
PREVAILING VFR THROUGH 12Z TUESDAY. OUR NEXT CHANCE OF
CONVECTION AT THE AIRFIELDS WILL ARRIVE DURING THE AFTERNOON IN
RESPONSE TO THE SEA BREEZE...VARIOUS BOUNDARIES AND SOME ENERGY
ALOFT. PROBABILITIES ARE STILL NOT SUFFICIENT ENOUGH TO SHOW WITH
THE 12Z TAFS...SINCE MODEL CONSENSUS IS POOR. THERE IS THEN THE
RISK OF A CLUSTER OF ORGANIZED CONVECTION /AN MCS/ THAT COULD
APPROACH FROM THE NORTH/NW TONIGHT. BUT AGAIN THE MODEL CONSENSUS
IS LACKING. HOWEVER...SHOULD ANY CONVECTION DIRECTLY IMPACT THE
TERMINALS...EITHER THIS AFTERNOON OR TONIGHT...THEN THEN PERIODIC
FLIGHT RESTRICTIONS WOULD OCCUR.
EXTENDED AVIATION OUTLOOK...VFR CONDITIONS SHOULD GENERALLY PREVAIL
THROUGH LATE WEEK...BUT FLIGHT RESTRICTIONS WILL BE POSSIBLE WITH
SHOWERS AND/OR THUNDERSTORMS...ESPECIALLY TUESDAY AFTERNOON THROUGH
WEDNESDAY EVENING.
&&
.MARINE...
TODAY...CURRENT MARINE OBSERVATIONS SHOW FORECAST IS ON TRACK. A
RECOGNIZABLE SYNOPTIC PATTERN WILL AGAIN PREVAIL...SIMILAR TO WHAT
WE HAVE SEEN MUCH OF THE PAST SEVERAL WEEKS. A NE-SW ALIGNED
PIEDMONT TROUGH AND SUB- TROPICAL ATLANTIC RIDGING ACROSS FLORIDA.
THIS PROVIDES THE REGION WITH A SW FLOW THIS MORNING...BEFORE
WINDS BACK TO THE SOUTH WITH SEA BREEZE INFLUENCES THIS AFTERNOON.
WINDS WILL HOLD AT OR BELOW 10 OR 12 KT THIS MORNING...THEN RISE
UP TO 12- 16 KT THIS AFTERNOON...GREATEST IN CHARLESTON HARBOR
AND THE CHARLESTON COUNTY ATLANTIC WATERS. OF COURSE SHOULD
CONVECTIVE CLOUDINESS INCREASE IN GREATER COVERAGE...THEN THIS
FORECAST MIGHT BE A BIT ON THE HIGH SIDE. BUT BASED ON THESE WINDS
WE LOOK FOR SEA NO MORE THAN 2 OR 3 FT.
TONIGHT...OUR FORECAST IS BASED ON A SCENARIO OF INLAND TROUGH AND
RIDGING TO THE SOUTH/SE...WITH DECENT NOCTURNAL JETTING INFLUENCES TO
BOOST SOUTH/SW WINDS UP TO 15-20 KT AND GUSTY. WE MIGHT EVEN FLIRT
WITH MARGINAL SCA/S OVER OUR AMZ350 AS A RESULT. HOWEVER...SHOULD
ANY CONVECTIVE COMPLEXES DEVELOP OVER OR NEAR THE AREA THEN ALL
BETS ARE OFF...AS CONVECTION WILL STRONGLY IMPACT THESE EXPECTED
SYNOPTIC WINDS.
TUESDAY THROUGH SATURDAY...THE COASTAL WATERS WILL REMAIN SITUATED
BETWEEN HIGH PRESSURE OVER THE WESTERN ATLANTIC AND A TROUGH OF LOW
PRESSURE INLAND TO START OFF THE WEEK. A WEAK COLD FRONT COULD SHIFT
OVER THE WATERS WEDNESDAY...WITH SOME STRONGER THUNDERSTORMS AHEAD
OF IT STARTING TUESDAY NIGHT. MARGINAL SMALL CRAFT ADVISORY LEVEL
CONDITIONS WILL ALSO BE POSSIBLE AS THE PRESSURE GRADIENT TIGHTENS
AHEAD OF THE APPROACHING FRONT...STARTING TUESDAY AFTERNOON AND
PERSISTING INTO WEDNESDAY NIGHT. WEAK LOW PRESSURE SHOULD THEN
SETTLE OVER THE WATERS INTO LATE WEEK.
IN GENERAL...SOUTH/SOUTHWEST WINDS WILL INCREASE TO 15-20 KTS WITH
GUSTS AROUND 25 KTS TUESDAY AFTERNOON INTO WEDNESDAY NIGHT. WINDS
SHOULD THEN IMPROVE LATE WEEK AND BECOME MORE ONSHORE AS WEAK LOW
PRESSURE REMAINS CENTERED INLAND. SEAS WILL RANGE BETWEEN 2-4 FT
EARLY ON TUESDAY...THEN GRADUALLY BUILD TO 3-5 FT MID WEEK. WE COULD
SEE 6 FT SEAS IN OUTER GEORGIA WATERS MID WEEK. SEAS SHOULD THEN
SUBSIDE LATE WEEK.
&&
.CHS WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
SC...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...
NEAR TERM...FWA
SHORT TERM...
LONG TERM...
AVIATION...
MARINE...
AREA FORECAST DISCUSSION
NWS NORTHERN INDIANA
1133 AM EDT MON JUL 13 2015
.SYNOPSIS...
ISSUED AT 1133 AM EDT MON JUL 12 2015
THUNDERSTORMS ARE EXPECTED TO DEVELOP ACROSS THE AREA LATER THIS
AFTERNOON AND EVENING WITH SEVERE WEATHER POSSIBLE ALONG AND SOUTH
OF US 30. AFTERNOON HIGHS WILL BE AROUND 80 IN SOUTH CENTRAL
MICHIGAN TO THE UPPER 80S INTO NORTHWEST AND WEST CENTRAL INDIANA.
&&
.UPDATE...
ISSUED AT 1131 AM EDT MON JUL 13 2015
GROWING CONCERN FOR SIGNIFICANT SEVERE WEATHER THIS
AFTERNOON...MAINLY SOUTH OF US 30. TEMPERATURES HAVE ALREADY JUMPED
INTO THE UPPER 70S ACROSS NORTHERN ILLINOIS IN THE WAKE OF MORNING
CONVECTION. EXPECT TEMPERATURES TO RISE QUICKLY IN OUR AREA BY EARLY
AFTERNOON. FULL SUN FOR SEVERAL HOURS AND EFFICIENT
EVAPOTRANSPORATION SHOULD RESULT IN MODERATE TO EXTREME
DESTABILIZATION ALONG AND WEST OF A MICHIGAN CITY TO FORT WAYNE
LINE. LAST FEW RUNS OF THE HRRR HAVE SUPPORTED THIS THINKING WITH
STORMS DEVELOPING ALONG THIS FRONT BY LATE AFTERNOON. IF STORMS
DEVELOP IN THAT ENVIRONMENT...SUPERCELLS WILL BE THE PRIMARY STORM
MODE WITH 0-6 KM SHEAR IN EXCESS OF 50 KNOTS...STEEP MID LEVEL LAPSE
RATES...AND SIGNIFICANT TURNING OF THE WINDS WITH HEIGHT. TORNADOES
WILL ALSO BE POSSIBLE IN THIS SCENARIO GIVEN SOUTHERLY SURFACE WINDS
AND AN INCREASINGLY STRONG LOW LEVEL JET FROM THE WEST. MAY NEED TO
ADD SEVERE WORDING TO THE GRIDS WITHIN THE NEXT FEW HOURS IF
DESTABILIZATION BEGINS AS EXPECTED.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 458 AM EDT MON JUL 13 2015
INTERESTING CONDITIONAL SEVERE EPISODE IN THE MAKE WITH NOTABLE
VARIABLES WHICH INCLUDE ONGOING SEVERE UPSTREAM CONVECTION ACRS
SRN/CNTL WI AND RESULTANT OUTFLOWS/BOUNDARIES AND CONVECTIVE
RENEWAL TIMING UPSTREAM BY MID/LATE AFTN WITH LOW POTNL FOR
DUAL/CONSECUTIVE CONVECTIVE COMPLEXES WITH THE LATTER NOT TO TRACK
THROUGH REGION UNTIL EARLY TUE AM...SEVERAL HOURS AFTER FIRST.
WILL FOCUS PRIMARILY ON THE FIRST TWO EPISODES WITH MAINTENANCE OF
CONVECTION FAVORED ALONG SHARP INSTABILITY/ISODROSOTHERMAL
GRADIENT WHICH SHOULD FOCUS WI BOWING SEGMENT APEX OF WI SQUALL
LINE ADVANCEMENT MORE RIGHT/SRLY WITH TIME...ADVANCING INTO WRN
CWA AFTER 12 UTC. STRENGTHENING WNWLY STEERING FLOW SHOULD ALSO
ALLOW EWD SPREAD THROUGH SCNTL CWA THROUGH AM HOURS AS STORMS
BECOME ELEVATED INTO ERN FRINGES OF WARM ADVECTION LEAF. PRIMARY
COMPOSITE OUTFLOW CORE TO LIKELY EXTEND NW/SE FM NRN IL TO WCNTL
IN. ESTABLISHED RICH POOL OF LWR/MID 70S SFC DPS ACRS MID MS VLY
WITH ERN BOUNDARY THROUGH NERN IL TO SRN IN. AS UPSTREAM SWRLY
FLOW STRENGTHENS LATER TODAY STRONG THETA-E ADVECTION INTO
SWRN/SRN CWA...ENHANCED FURTHER BY EFFECTIVE CNTL IL
EVAPOTRANSPIRATIVE PROCESSES...WILL FOCUS STRONG SFC BASED
INSTABILITY RESERVOIR /5000+ J/KG IN SWEPT ARC S-SW- W-NW OF CWA
BY MID/LATE AFTN. MEANWHILE STRENGTHENING AND VEERING MID
TROPOSPHERIC FLOW TO 50-60KTS. FOCUS FOR INITIATION UPSTREAM ACRS
WI IN MID/LATE AFTN HOURS APPEARS TIED TO EJECTION OF DUMBELLED
SHORTWAVE FEATURE ACRS NRN MN TIED TO PRESENTLY REXED WAVE NEAR
ND/SASK/MAN BORDERS. AS LEAD SHORTWAVE ENTERS RAPID CONFLUENCY
BTWN HUDSON BAY VORTEX AND STOIC NRN TX RIDGE. SHOULD BE
SUFFICIENT INDUCEMENT TO CONVECT WITH SUBSEQUENT/RAPID
INTENSIFICATION...WITH EVOLUTION INTO LINEAR SEGMENT/S/ BY EVENING
AND ENTRY INTO NWRN/WRN CWA BYND 00 UTC. DEEP LYR SHEAR ON ORDER
OF 45 KTS FAR SWRN CWA TO 30 KTS NE ALONG WITH PRESENTATION OF
INSTABILITY FAVORS SWRN/SRN CWA FOR SEVERE WITH DAMAGING WIND
GUSTS LARGEST RISK GIVEN MID LEVEL SPEEDS ENTRAINED INTO REAR
INFLOWS. HIGHLY CONDITIONAL NATURE OF THIRD LATE PD 2 EPSIODE TOO
UNCERTAIN AND DWINDLE SCT TSRA/HIR SHRA POPS TO CHC BYND 06 UTC.
LACK OF STRONG DESTABILZATION DOWNSTREAM OF CONVECTION TRAVERSING
SRN LK MICHIGAN SHOULD KEEP STORMS ACRS NERN CWA BLO SVR LIMITS.
&&
.LONG TERM...(TUESDAY THROUGH SUNDAY)
ISSUED AT 458 AM EDT MON JUL 13 2015
LONG TERM FORECAST FAIRLY QUIET FROM A RELATIVE PERSPECTIVE. MAIN
VORTICITY LOBE AND ASSOCIATED SECONDARY LOW LEVEL FRONTAL BOUNDARY
WILL PUSH THROUGH OUR AREA DURING THE DAY TUESDAY. PRIMARY THETA-E
RIDGE LONG GONE BY THAT POINT BUT ENOUGH RESIDUAL MOISTURE TO TOUCH
OFF SCT/NUM SHOWERS...ESPECIALLY IN OUR SOUTHERN ZONES. ALSO SOME
MARGINAL INSTABILITY IN THOSE SOUTHERN COUNTIES SO WOULD NOT BE
SURPRISED TO SEE SOME EMBEDDED THUNDER. QPF AMOUNTS WILL BE FAIRLY
LIGHT BUT THE HIGHEST AMOUNTS (0.25-0.5 INCHES) WILL BE IN THE SOUTH
AND MAY PROLONG FLOODING DUE TO SHORT TERM CONVECTION.
WED/THURS STILL LOOKING DRY AS GREAT LAKES RECEIVE A HEALTHY DOSE OF
AVA/SUBSIDENCE IN THE WAKE OF DEPARTING TROUGH AXIS. NORTHEAST FLOW
WILL YIELD A SLIGHT COOL DOWN BUT THERMAL PROFILES NOT PARTICULARLY
COLD AND WILL BE AT LEAST PARTIALLY OFFSET BY A FAIR AMOUNT OF SOLAR
INSOLATION. KEPT HIGHS IN THE UPPER 70S TO AROUND 80F. RETURN TO
MORE ACTIVE WEATHER BY THE END OF THE WEEK AS A MUCH WARMER AND
MOISTURE-LADEN AIRMASS FOLDS BACK INTO THE OHIO VALLEY COURTESY OF
STALWART SOUTHERN PLAINS RIDGE. WESTERLY MID/UPPER LEVEL FLOW WILL
BRING ANOTHER PARADE OF LOW AMPLITUDE SYSTEMS INTO THE WEEKEND BUT
(NOT SURPRISINGLY) MEDIUM RANGE MODELS CONTINUE TO STRUGGLE
IMMENSELY WITH EXACT TIMING AND PLACEMENT. WILL CONTINUE TO HOLD
WITH LOW CHANCE POPS UNTIL DETAILS CAN BE SORTED OUT.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z TUESDAY MORNING)
ISSUED AT 730 AM EDT MON JUL 13 2015
UPSTREAM CONVECTION INVOF KSBN AND LINEAR COMPLEX OVR SRN LK MI
REQUIRES TSRA MENTION FROM START AT KSBN THROUGH 15 UTC. TIMING OF
LINE TO KFWA ROUGHLY AROUND 15 UTC. PERTURBED MOIST BOUNDARY
LAYER AND PRECIP SHOULD CONTINUE TO SUPPORT FUELING/ALTERNATE CIGS
IF NOT BRIEF IFR UNTIL PASSAGE OF TSRA. THEREAFTER...GREAT DEAL OF
UNCERTAINTY ESPECIALLY WITH RESPECT TO TIMING AND POTNL FOR
RENEWED CONVECTION. FOR NOW COVER WITH VCTS AT 02/04 UTC FOR
&&
.IWX WATCHES/WARNINGS/ADVISORIES...
IN...FLASH FLOOD WATCH THROUGH LATE TONIGHT FOR INZ003-012-013-015-
020-022>027-032>034.
MI...NONE.
OH...NONE.
LM...NONE.
&&
$$
UPDATE...BENTLEY
SYNOPSIS...MURPHY
SHORT TERM...MURPHY
LONG TERM...AGD
AVIATION...MURPHY
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AREA FORECAST DISCUSSION
NWS GRAND RAPIDS MI
1157 AM EDT MON JUL 13 2015
LATEST UPDATE...
MESOSCALE DISCUSSION
.MESOSCALE DISCUSSION...
ISSUED AT 1157 AM EDT MON JUL 13 2015
A BRIEF PERIOD OF STRONGER EAST/SOUTHEAST SFC WINDS WITH GUSTS TO
30-35 MPH HAVE BEEN NOTED AT A FEW OB SITES ON THE BACK SIDE OF
THE AREA SHOWERS AND THUNDERSTORMS THIS MORNING. THIS IS WAKE LOW
DRIVEN AND THE WINDS SHOULD RETURN TO UNIFORM SOUTHWEST 5 TO 15
MPH THIS AFTERNOON.
EXPECT A RELATIVE LULL IN CONVECTIVE POTENTIAL BEHIND DEPARTING
MORNING CONVECTION AND POSSIBLY SOME SUNSHINE AS WELL.
UNFORTUNATELY CONFIDENCE IS LOW REGARDING COVERAGE/INTENSITY OF
CONVECTION LATER TODAY AND TONIGHT DUE TO DIFFERING SOLUTIONS IN
SHORTER RANGE GUIDANCE. CONSENSUS HOWEVER SEEMS TO BE THAT IF
ANYTHING OCCURS IT WOULD BE AFTER 00Z WITH THE APPROACH OF THE MID
LEVEL SHORTWAVE AND SFC COLD FRONT FROM THE NORTHWEST.
THE LATEST RAP GUIDANCE SHOWS MU CAPES RISING TO 1500-2500 J/KG
ALONG THE I-94 CORRIDOR AFTER 18Z AND LINGERING WELL INTO THE
EVENING. 0-6 KM SHEAR VALUES ARE PROGGED TO BE 30-40 KNOTS SO
THERE IS SOME POTENTIAL FOR A CLUSTER OR TWO OF ORGANIZED STRONG
TO SVR STORMS WITH WIND GUSTS OVER 50 MPH TO RIDE NW TO SE
THROUGH SW LWR MI THIS EVENING.
.SYNOPSIS...
ISSUED AT 306 AM EDT MON JUL 13 2015
A WAVE OF LOW PRESSURE WILL TRACK SOUTHEASTWARD FROM THE NORTHERN
PLAINS AND INTO THE GREAT LAKES REGION TODAY INTO TUESDAY. THIS
SYSTEM WILL GENERATE SCATTERED SHOWERS AND THUNDERSTORMS. THE
MOISTURE WILL BE ON THE INCREASE AS THIS SYSTEM MOVES IN. A MUCH
DRIER AIRMASS ARRIVES ON WEDNESDAY AS THE WINDS SHIFT AND BECOME
NORTHERLY.
&&
.UPDATE...
ISSUED AT 750 AM EDT MON JUL 13 2015
STRONGER CONVECTION MOVING INTO WRN ZONES WILL CAUSE MORE
WIDESPREAD PRECIPITATION THAN CURRENTLY FORECAST. THE ZONES HAVE
BEEN UPDATED TO REFLECT THIS TREND.
UPDATE ISSUED AT 642 AM EDT MON JUL 13 2015
ADDED SOME DENSE FOG TO THE FORECAST THIS MORNING FOR THE AREA
SOUTH OF INTERSTATE 96. SEVERAL SITES SHOWING VALUES AROUND A
QUARTER MILE.
&&
.SHORT TERM...(TODAY THROUGH WEDNESDAY)
ISSUED AT 306 AM EDT MON JUL 13 2015
MCS TRACKING THROUGH WRN WI...WILL DIVE SOUTHEAST WITH THE
STRONGEST CONVECTION STAYING SOUTHWEST OF THE CWA. THIS IS
EXPECTED TO HAPPEN BECAUSE THERE IS VERY LITTLE IN THE WAY OF
INSTABILITY PRESENT OVER SOUTHWEST LOWER MI BASED OFF THE MESO
ANALYSIS PAGE FROM SPC. WE SHOULD SEE ELEVATED SHOWERS WITH
EMBEDDED THUNDERSTORMS MOVING INTO MAINLY COASTAL LOCATIONS THIS
MORNING. WILL KEEP THE HIGH POPS GOING FOR WRN ZONES THIS
DECAYING MCS.
THIS AFTERNOON WILL NEED TO BE MONITORED FOR POSSIBLE STRONGER
CONVECTION. OVERALL IT APPEARS THE MODELS MAY HAVE TOO MUCH
INSTABILITY AS DEBRIS CLOUDS SHOULD PERSIST THROUGH MUCH OF THE
MORNING INTO THE EARLY AFTERNOON HOURS. DEEP LAYER SHEAR DOES
INCREASE...SO A RISK OF ORGANIZED CONVECTION IS ELEVATED. HOWEVER
THE COVERAGE OF STORMS MAY BE LIMITED UNTIL THE PEAK HEATING WHICH
MAY NOT OCCUR UNTIL MID TO LATE AFTERNOON. WILL HOLD ONTO THE
CHANCE FOR STORMS THIS AFTERNOON.
TONIGHT WE WILL SEE A MOIST ATMOSPHERE WITH PWATS OVER 1.75
INCHES...MID LEVEL HEIGHT FALLS AS A SHORTWAVE DIGS IN AND SOME
INSTABILITY. SUSPECT WE WILL SEE THE CONVECTION INCREASE AGAIN.
THIS INSTABILITY LOOKS LIMITED SO IT APPEARS UNLIKELY THAT WE WILL
SEE AN MCS DEVELOP. SOUTHWEST ZONES WILL SEE THE MOST INSTABILITY
AND BEST SHEAR SO THIS IS THE REGION THAT WILL NEED TO BE
MONITORED.
ADDITIONAL STORMS ARE POSSIBLE TUE AS THE MID LEVEL WAVE PUSHES
OFF TO THE EAST AND FLOW ALOFT IS CYC. WILL KEEP THE LOW CHC
GOING.
.LONG TERM...(WEDNESDAY NIGHT THROUGH SUNDAY)
ISSUED AT 306 AM EDT MON JUL 13 2015
THE LONG TERM PORTION OF THE FCST IS EXPECTED TO START OUT QUIET AND
SEASONABLE...BEFORE LIKELY HEATING UP A BIT AND BECOMING POTENTIALLY
UNSETTLED THROUGH NEXT WEEKEND.
WE ARE EXPECTING MAINLY DRY WEATHER FOR THE WED NIGHT AND THU TIME
PERIODS FOR THE AREA. THE TROUGH MOVING THROUGH ON TUE WILL BE LONG
GONE...AND WE WILL SEE A BIT OF A LONG WAVE RIDGE SLOWLY BUILD
TOWARD THE AREA IN RESPONSE TO TROUGHING MOVING IN OVER THE PACIFIC
NW. THE LOW LEVEL FLOW N/NE FLOW WILL BE FROM CANADA KEEPING THE
ATMOSPHERE DRY.
THE THREAT OF SHOWERS AND STORMS WILL INCREASE THU NIGHT AND
CONTINUE INTO THE DAY ON FRI. THE UPPER RIDGE WILL SHIFT EAST OF THE
AREA. THERE WILL BE A FAIRLY DECENT SHORT WAVE BEING EJECTED FROM
THE PACIFIC NW LONG WAVE TROUGH THAT WILL APPROACH THE AREA. THE
TRACK OF THIS WAVE HAS BEEN INCONSISTENT...ALTHOUGH THERE SEEMS TO
BE A CONSENSUS DEVELOPING OF IT MOVING THROUGH AT LEAST A PORTION OF
THE AREA. THE INSTABILITY WITH THIS DOES NOT LOOK TO BE IMPRESSIVE
AT THIS TIME WITH CLOUDS AND PCPN COMING IN THU NIGHT AND LIMITING
HEATING ON FRI.
THERE IS SOME POTENTIAL THAT SAT COULD END BEING MAINLY DRY WITH
PCPN CHCS STARTING TO INCREASE BY LATER ON SUN. THE THU NIGHT/FRI
WAVE WILL EXIT THE AREA LEAVING SOME SHORT WAVE RIDGING FOR AT LEAST
ON SAT. WE ARE NOT SO SURE ABOUT SUN STAYING DRY AS IT APPEARS WE
WILL HAVE SHORT WAVES/STORM COMPLEXES THAT WILL BE APPROACHING THE
REGION AROUND THE PERIPHERY OF THE RIDGE. THE RISING HEIGHTS WILL
HELP H850 TEMPS APPROACH 20C WHICH WOULD GIVE THE AREA A POTENTIAL
OF POSSIBLY HITTING 90 FOR THE FIRST TIME THIS SUMMER.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z TUESDAY MORNING)
ISSUED AT 750 AM EDT MON JUL 13 2015
TAFS FEATURE MORE IFR THAN PREVIOUSLY FORECASTED...ESPECIALLY
SOUTHERN TAF SITES FROM KAZO...KBTL TO KJXN. THIS SHOULD LAST FOR
AN HR OR TWO THIS AM DUE TO FOG AND LOW CLOUDS. ALSO THE
THUNDERSTORMS MOVING INTO THE KMKG REGION WILL FEATURE VARIABLE
GUSTY WINDS...ESPECIALLY WRN TAF SITES KMKG AND KAZO. VISIBILITIES
COULD BE REDUCED IFR LEVELS AS WELL. ONCE THIS INITIAL ROUND OF
STORMS MOVES THROUGH...IT WILL TAKE TIL MID TO LATE AFTERNOON FOR
NEW STORMS TO DEVELOP.
&&
.MARINE...
ISSUED AT 306 AM EDT MON JUL 13 2015
THUNDERSTORMS WILL POSE A RISK TO MARINERS THROUGH TUESDAY.
OVERALL IT APPEARS THE WINDS WILL REMAIN LOW ENOUGH TO LIMIT THE
POTENTIAL FOR HAZARDOUS MARINE CONDITIONS. SOUTHERLY WINDS
AHEAD OF THE APPROACHING STORMS THIS MORNING SHOULD SUPPORT THE
HIGHEST WAVES NEAR LITTLE AND BIG SABLE POINTS. THE PRESSURE
GRADIENT DROPS OFF TONIGHT. WILL NEED TO MONITOR THE NORTHERLY
COOL AND DRY FLOW FOR TUE NIGHT INTO WEDNESDAY AS SOMETIMES THE
WAVES END UP HIGHER THAN EXPECTED IN THESE SITUATION.
&&
.HYDROLOGY...
ISSUED AT 144 PM EDT SUN JUL 12 2015
ALL RIVER SITES ARE CURRENTLY WITHIN BANK...BUT STREAMFLOWS ACROSS
MUCH OF THE AREA ARE RUNNING ABOVE NORMAL. PORTIONS OF THE GRAND
AND KALAMAZOO RIVER BASINS ARE RUNNING MUCH ABOVE NORMAL.
RAINFALL THROUGH WEDNESDAY MORNING LOOKS TO AVERAGE FROM A QUARTER
TO A HALF INCH ACROSS PORTIONS OF CENTRAL LOWER MICHIGAN TO
POTENTIALLY AROUND AN INCH TOWARDS VAN BUREN COUNTY.
WE ARE EXPECTING A DECAYING AREA OF SHOWERS AND THUNDERSTORMS TO
MOVE TOWARDS AND INTO SOUTHWEST LOWER MICHIGAN LATE TONIGHT AND
MONDAY MORNING. SHOWERS AND STORMS WILL THEN LIKELY REFIRE MONDAY
AFTERNOON AND EVENING AHEAD OF A LOW PRESSURE SYSTEM MOVING
THROUGH THE REGION.
DEPENDING ON THE INTENSITY OF THE RAINFALL...OR IF RAINFALL OVER
PERFORMS JUST A BIT WE COULD BE LOOKING AT SOME RIVER ADVISORIES
ONCE AGAIN. THE HEAVIEST RAIN IN OUR AREA WILL BE IN AREAS SOUTH
OF INTERSTATE 96 MOST LIKELY.
&&
.GRR WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LM...NONE.
&&
$$
MESOSCALE...MEADE
UPDATE...MJS
SYNOPSIS...MJS
SHORT TERM...MJS
LONG TERM...NJJ
AVIATION...MJS
HYDROLOGY...DUKE
MARINE...MJS
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
740 AM EDT MON JUL 13 2015
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 507 AM EDT MON JUL 13 2015
WV IMAGERY AND RAP ANALYSIS INDICATED A BORAD MID/UPPER LEVEL RIDGE
CENTERED OVER THE SRN PLAINS AND A TROUGH OVER SRN MANITOBA. AT THE
SFC...A FRONTAL BOUNDARY FROM SE NORTH DAKOTA THROUGH SE MN INTO NRN
IL. THE STRONGEST CONVECTION WITH A LARGE MCS THAT DEVELOPED OVER MN
HAS SLIDE SE INTO CNTRL/SRN WI ALONG AND NORTH OF THE FRONT AND
MUCAPE GRADIENT. SHOWERS AND EMBEDDED TSRA ASSOCIATED WITH THE
LEFTOVER MCV PERSISTED INTO WRN LAKE SUPERIOR AND WRN UPPER MI.
TODAY...RADR TRENDS AND SHORT RANGE HIGH RES MODELS SUGGEST THAT THE
SHRA/TSRA OVER WRN UPPER MI WILL CONTINUE TO GRADUALLY SLIDE TO THE
EAST EARLY THIS MORNING WHILE ALSO WEAKENING AS THE PCPN MOVES AWAY
FROM THE AREA OF GREATER INSTABILITY. HOWEVER...THE APPROACH OF A
WEAK SHRTWV IN ADVANCE OF THE MANITOBA TROUGH MAY RESULT IN
ADDITIONAL DEVELOPMENT BY LATE MORNING INTO THE EARLY AFTERNOON AS
DAYTIME HEATING INCREASES AND A WEAK SFC TROUGH MOVES THROUGH THAT
COULD ALSO INTERACT WITH LAKE BREEZE BOUNDARIES. OVERALL CONFIDENCE
IN PCPN TIMING/COVERAGE IS LOW GIVEN MODEL DIFFERENCES AND LINGERING
EFFECTS OF THE LARGE MCS. WITH FCST MLCAPE VALUES ONLY INTO THE 500-
1000 J/KG RANGE AND WEAK 0-6KM/0-1KM SHEAR MAINLY JUST BRIEF HEAVY
RAIN WOULD BE THE MAIN HAZARD.
TONIGHT...EXPECT THE MID LEVEL TROUGH INTO THE NRN LAKES TO
GRADUALLY SINK OFF TO THE SE. WITH THE LOSS OF DAYTIME INSTABILITY
AND ANY WEAK MID LEVEL FORCING WITH THE TROUGH...SHRA/TSRA WILL
DIMINISH FROM THE NW OVERNIGHT. THERE MAY BE SOME SHOWERS LATE INTO
THE NORTH AS THE COLD FRONT SLIDES INTO THE AREA.
.LONG TERM...(TUESDAY THROUGH SUNDAY)
ISSUED AT 529 AM EDT MON JUL 13 2015
OUR OFF AND ON SHOWER/TS ACTIVITY WILL BE DIMINISHING SIGNIFICANTLY
AFTER TUESDAY MORNING...AND MAY BE MORE LIMITED THROUGH THE REST OF
THE FCST PERIOD IF THE NEXT COUPLE OF SYSTEMS ARE UNABLE TO BREAK
DOWN THE STUBBORN 500MB RIDGE ACROSS MUCH OF THE CENTRAL U.S.
EXPECT SOME BRIEF GUSTY WINDS TUESDAY AS THE DEEPENING SFC LOW OVER
N LOWER MI AT 12Z SINKS ACROSS LAKE ERIE...AND LARGE HIGH PRESSURE
PUSHES IN FROM CENTRAL CANADA. THIS WILL BE WHILE THE 500MB LOW OVER
N QUEBEC AND TROUGH EXTENDING ACROSS LOWER MI EXIT TOO.
PW VALUES WILL FALL FROM AN AVG 1.5IN AT 12Z TUESDAY TO 0.3IN
TUESDAY NIGHT AS 850MB TEMPS FALL TO AROUND 11C /FROM NEAR 16C/.
MODEL GUIDANCE FOLLOWS THIS TREND PRETTY WELL...AND LOWERING THE
OVERNIGHT TEMPS EVEN MORE FOR TUESDAY NIGHT MAY BE NECESSARY BY
LATER SHIFTS. CURRENTLY EXPECT TEMPS TO BOTTOM OUT IN THE MID 40S TO
RIGHT AROUND 50F...WARMEST ALONG THE GREAT LAKES SHORELINES. LOOK
FOR SLOWLY INCREASING MOISTURE DURING THE DAY WEDNESDAY. THE SFC
HIGH WILL BE DIRECTLY OVER UPPER MI WEDNESDAY AFTERNOON...BEFORE
SLOWLY CENTERING ACROSS LAKE HURON AND THE LOWER GREAT LAKES
THURSDAY AFTERNOON...AND THE NEW ENGLAND STATES THURSDAY EVENING.
A LARGE AREA OF HIGH PRESSURE OVER S CENTRAL AND THE N TO CENTRAL
PLAINS STATES THURSDAY EVENING WILL BE PRESENT THROUGH THE WEEKEND.
THE 500MB RIDGE ACROSS MUCH OF THE E TWO-THIRDS OF THE NATION LOOKS
TO BECOME MORE ZONAL OVER THE UPPER GREAT LAKES FRIDAY MORNING. THE
RIDGE WILL REBOUND SATURDAY. THERE ARE SOME SIGNIFICANT DIFFERENCES
BETWEEN THE GFS AND ECMWF LATE SUNDAY AFTERNOON INTO MONDAY. A
GENERAL MODEL BLEND LOOKS TO BE BEST THAT FAR OUT...WITH 20-40
PERCENT POPS.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z TUESDAY MORNING)
ISSUED AT 737 AM EDT MON JUL 13 2015
SHOWERS AND AN INFLUX OF LOW LEVEL MOISTURE HAS DROPPED CIGS TO IFR
AT TIMES AT CMX AND SAW. HOWEVER...CONDITIONS HAD IMPROVED TO VFR AT
IWD BEHIND THE MCS THAT MOVED THROUGH OVERNIGHT. MORE SHOWERS AND
PERHAPS MVFR CONDITIONS MAY LINGER THROUGH MUCH OF THE MORNING AS
WELL AT CMX/SAW WITH THE MVFR CONDITIONS DOWN TO IFR AT TIMES. BUT
IN THE AFTERNOON...DAYTIME HEATING IS LIKELY TO CAUSE A RETURN TO
VFR WEATHER. THIS HEATING MAY ALSO CAUSE MORE SHOWERS AND PERHAPS A TS TO
DEVELOP AS WELL...ESPECIALLY AT IWD AND SAW AWAY FROM LAKE SUPERIOR
MODERATION. MVFR CONDITIONS WILL BE POSSIBLE AGAIN BY LATE EVENING
WITH LINGERING LOW LEVEL MOISTURE AND NOCTURNAL COOLING. AS WINDS
VEER TO THE NORTH BEHIND A COLD FRONT...UPSLOPE FLOW IS EXPECTED TO
DROP CIGS BACK TO IFR AT CMX AND SAW AND POSSIBLY AT IWD.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 515 AM EDT MON JUL 13 2015
A WEAK TROUGH MOVING THROUGH THE NRN LAKES TODAY INTO THIS EVENING
WILL KEEP WINDS BELOW 20 KNOTS. A COLD FRONT WILL DROP SOUTH ACROSS
LAKE SUPERIOR LATE TONIGHT...SHIFTING THE WINDS TO A NORTHERLY
DIRECTION. WINDS MAY INCREASE TO AROUND 20 KNOTS LATE TONIGHT INTO
TUE MORNING BEHIND THE FRONT BUT SHOULD DIMINISH TUE AFTERNOON. A
HIGH PRESSURE RIDGE WILL THEN MOVE OVER LAKE SUPERIOR FOR TUESDAY
NIGHT THROUGH WEDNESDAY NIGHT AND KEEP WINDS LIGHT.
AREAS OF FOG WILL CONTINUE TO AFFECT LAKE SUPERIOR TODAY INTO
TONIGHT AS WINDS REMAIN RELATIVELY LIGHT AND ABUNDANT LOW LEVEL
MOISTURE REMAINS OVER THE REGION. SO...THE DENSE FOG ADVY REMAINS IN
EFFECT THROUGH TONIGHT. AS DRIER AIR AND STRONGER MIXING ARRIVE
LATER TUESDAY INTO TUESDAY NIGHT BEHIND THE COLD FRONT...EXPECT THE
FOG TO DISSIPATE.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
DENSE FOG ADVISORY UNTIL 8 AM EDT TUESDAY FOR LSZ263-264-266.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...JLB
LONG TERM...KF
AVIATION...JLB
MARINE...JLB
AREA FORECAST DISCUSSION...UPDATED
NWS BILLINGS MT
927 AM MDT MON JUL 13 2015
.UPDATE...
MADE ONLY A FEW ADJUSTMENTS TO THE INHERITED FORECAST. RADAR
SHOWED SOME CONVECTION OVER S ID STRETCHING INTO NW WY. THIS
CONVECTION WAS OCCURRING UNDER STREAMWISE VORTICITY IN THE SW FLOW
ALOFT ON THE WESTERN SIDE OF THE UPPER RIDGE OVER THE FORECAST
AREA. THE FLOW WILL BECOME SW OVER THE AREA THROUGH THIS EVENING
AND WILL CONTINUE ON TUE. THIS WILL ALLOW WEAK ENERGY TO MOVE
ACROSS THE AREA. INSTABILITY WILL BE BETWEEN 500-1000 J/KG THIS
AFTERNOON THROUGH 03Z THIS EVENING BASED ON THE SREF...ALTHOUGH
THE RAP WAS NOT AS UNSTABLE. SHEAR WILL BE LIMITED. MODELS LIMITED
THE CONVECTION TO OVER AND NEAR THE TERRAIN TODAY WHICH LOOKED
REASONABLE.
GOOD MIXING TO 700-600 MB WILL RESULT IN INVERTED-V SOUNDINGS.
WINDS WERE STILL 20 TO 30 KT AT 700 MB THIS AFTERNOON OVER THE
EASTERN ZONES WHICH WILL RESULT IN 15 TO 25 MPH MIXDOWN WINDS
THERE. BASED ON THE RAP DEWPOINTS THIS AFTERNOON...HAVE TRENDED
FORECAST DEWPOINTS A FEW DEGREES LOWER...RESULTING IN RH/S IN THE
TEENS OVER THE E ZONES. TEMPERATURES IN THE 80S TO LOWER 90S WERE
IN GOOD SHAPE. ADJUSTED SKY COVER TO COINCIDE CLOSER TO THE
OBSERVED VISIBLE SATELLITE THROUGH 18Z.
MODELS KEPT CHANCES FOR CONVECTION GOING THROUGH THE NIGHT WHICH
WAS IN LINE WITH THE PREVIOUS FORECAST. CHANCES FOR CONVECTION
WILL CONTINUE ON TUE. THE SREF SHOWED THE POTENTIAL FOR HIGHER
CAPES ACROSS THE AREA ON TUE WITH LOW SHEAR...SO WILL NEED TO
WATCH FOR SOME POSSIBLE STRONG STORMS ON TUE. ARTHUR
&&
.SHORT TERM...VALID FOR TDY AND TUE...
TODAY WILL BE DOMINATED BY SHORT WAVE RIDGING. WINDS WILL AGAIN BE
OUT OF THE WEST. THIS DOWNSLOPE FLOW COMBINED WITH THE SUBSIDENCE
FROM THE RIDGE SHOULD SUPPRESS RAIN CHANCES. HAVING SAID
THAT...SOME MID LEVEL MOISTURE IS STILL PRESENT ACROSS THE AREA
AND OVER THE MOUNTAINS SOME SHOWERS AND THUNDERSTORMS ARE
POSSIBLE.
HIGHS WILL AGAIN BE RISING INTO THE UPPER 80S TO LOWER 90S THIS
AFTERNOON. THESE WARM TEMPERATURES WILL HELP TO DEEPLY MIX THE
ATMOSPHERE. THIS WILL HELP TO INCREASE WINDS THIS
AFTERNOON...CREATING WINDS SIMILAR TO YESTERDAY. WIND GUSTS UP TO
35 MPH ARE POSSIBLE THIS AFTERNOON.
OVERNIGHT WHILE MUCH OF THE AREA WILL REMAIN DRY...A WEAK PULSE
OF ENERGY WILL MOVE ACROSS WESTERN MONTANA ALONG WITH SOME JET
DIVERGENCE. THIS WILL AT LEAST KEEP SOME RAIN CHANCES IN THE
MOUNTAINS AND SOME MAY DRIFT OFF ONTO THE ADJACENT PLANES.
FOR TUESDAY...THE RIDGE WILL SHIFT TO THE EAST WHICH WILL PUT THE
AREA IN SOUTHWEST FLOW. CAPE VALUES WILL BE GETTING INTO THE 500
TO 1500 J/KG RANGE WITH SOME DECENT SHEAR. THE SETUP DOES NOT LOOK
LIKE WIDESPREAD SEVERE WEATHER...BUT A FEW THUNDERSTORMS COULD BE
STRONG TO SEVERE. REIMER
.LONG TERM...VALID FOR WED...THU...FRI...SAT...SUN...
MODELS CONTINUE TO SHOW BASIC BROAD PATTERN SIMILARITIES THROUGH
MOST OF THE EXTENDED PERIOD...BUT VARY IN THE TIMING OF SHORT
WAVES WITHIN THE FLOW. WE USED A BLEND OF SOLUTIONS FOR THE MOST
PART AS TIMING SHORT WAVES THIS FAR OUT IS OFTEN FUTILE...BUT DID
LEAN TOWARD CLIMATOLOGY FOR TIMING.
MODELS DO TEND TO AGREE ON THE MOST ACTIVE THUNDERSTORM DAYS
BEING WEDNESDAY AND FRIDAY EVENING. THERE IS POTENTIALLY A DECENT
COOLING TREND TOWARD THE WEEKEND AS A TROUGH DROPS INTO THE
NORTHWEST AND NORTHERN ROCKIES...BUT THE GFS AND ECMWF HANDLE THIS
FEATURE DIFFERENTLY WITH THE GFS DROPPING THE UPPER LOW DOWN THE
WEST COAST AND THE ECMWF TAKING THE TROUGH AXIS ACROSS US.
AGAIN...WE LEANED ON BLENDS AS 500MB ENSEMBLE SPREADS WERE RATHER
WIDE UPSTREAM OF OUR REGION OUT ALONG THE NORTHWEST COAST. BT
&&
.AVIATION...
MOSTLY CLEAR CONDITIONS CAN BE EXPECTED OVER AREAS EAST OF KBIL
THROUGH 21Z. ISOLATED SHOWERS/THUNDERSTORMS ARE POSSIBLE OVER THE
WESTERN TERRAIN MAINLY AFTER 20Z. MOUNTAIN OBSCURATIONS WILL BE
POSSIBLE IN THESE SHOWERS/TSRA. ANY SHOWERS/STORMS THAT FORM WILL
BE MOVING EASTWARDS AND WE COULD SEE VCSH/VCTS IN BIL/SHR...MAINLY
FROM 00-06Z. CS/WD
&&
.PRELIMINARY POINT TEMP/POPS...
TDY TUE WED THU FRI SAT SUN
-------------------------------------------------------
BIL 090 061/087 060/086 060/089 060/084 056/078 057/082
1/B 33/T 33/T 30/B 22/T 43/T 32/T
LVM 087 053/082 053/082 052/084 053/080 051/077 050/081
2/T 34/T 34/T 32/T 23/T 43/T 42/T
HDN 092 059/091 057/087 058/090 059/085 056/081 056/085
1/B 23/T 34/T 30/B 22/T 33/T 22/T
MLS 092 062/092 062/091 062/091 062/087 059/084 059/085
0/U 12/T 32/T 40/B 22/T 53/T 22/T
4BQ 091 061/092 062/090 060/090 061/089 058/084 059/084
0/U 13/T 33/T 40/B 22/T 22/T 22/T
BHK 089 059/089 061/089 059/088 059/086 057/084 058/082
0/N 02/T 34/T 41/B 22/T 42/T 22/T
SHR 088 055/087 055/085 055/086 056/086 054/080 054/082
2/T 24/T 33/T 21/B 22/T 22/T 22/T
&&
.BYZ WATCHES/WARNINGS/ADVISORIES...
MT...NONE.
WY...NONE.
&&
$$
WEATHER.GOV/BILLINGS
AREA FORECAST DISCUSSION
NWS OMAHA/VALLEY NE
639 AM CDT MON JUL 13 2015
.SHORT TERM...(TODAY THROUGH WEDNESDAY)
ISSUED AT 310 AM CDT MON JUL 13 2015
HEAT AND HUMIDITY TODAY...ISOLATED STORMS INTO MID MORNING AND
THEN SLIGHT CHANCE OF TSTMS LATE TODAY INTO THIS EVENING ARE THE
PRIMARY FORECAST CONCERNS THROUGH THIS PERIOD.
UPPER AIR CHARTS FROM LAST EVENING SHOWED THE FOLLOWING. AT 300 MB
A JET STREAK OF 80-90 KNOTS EXTENDED FROM ERN WY ACROSS SRN SD. AT
500 MB...WEAK HEIGHT FALLS WERE MOVING EWD ACROSS THE DAKOTAS AND
MN AND RIDGE ALOFT WAS STILL CENTERED OVER TX. THERMAL RIDGE AT
700 MB STRETCHED FROM NM INTO CO AND KS. ACROSS NEBRASKA...700 MB
TEMPERATURES WERE GENERALLY 12-13 DEGREES C. THERMAL RIDGE AT 850
MB WAS LOCATED FROM NM INTO WRN SD. DRIER AIR WAS OVER THE HIGH
PLAINS BUT 850 MB DEWPOINTS WERE IN THE TEENS FROM IA BACK INTO
ERN NE. THE KOAX SOUNDING FROM 00Z WAS FAIRLY MOIST...WITH A
PRECIPITABLE WATER OF 1.48 INCHES. SURFACE ANALYSIS AT 08Z SHOWED
A TROUGH OF LOW PRESSURE CURVING FROM THE ERN SD INTO NWRN KS.
AHEAD OF THIS TROUGH...DEWPOINTS WERE MOSTLY IN THE 70S BUT DROP
TO 60S AND 50S WEST OF THE TROUGH.
JUST HOW FAST DRIER AIR WILL BE ABLE TO MOVE IN TODAY WILL HAVE A
BIG IMPACT ON HEAT INDICES. LEFT PREVIOUSLY ISSUED HEAT ADVISORY
AS IS...BUT MAY NEED A SLIGHT ADJUSTMENT LATER TODAY. OTHERWISE...
ISOLATED TSRA WERE OCCURRING OVER PARTS OF NERN NE. THESE WERE
VERY HIGH BASED...ABOVE THE MID LEVEL CAP AND POSSIBLY GETTING
SOME SUPPORT BY THE JET STREAK MENTIONED EARLIER AND VERY WEAK
MID LEVEL HEIGHT FALLS. THESE MAY LAST INTO MID MORNING AS THEY
CONTINUE TO TRACK EAST. AFTER THAT...THE REST OF THE DAY IS
EXPECTED TO BE DRY...EXCEPT DID INCLUDE A SLIGHT CHANCE OF TSTMS
IN OUR FAR SRN COUNTIES TOWARD 6 PM AND THEN THROUGH EARLY THIS
EVENING. HRRR AND SOME OF THE OTHER HIGH RESOLUTION MODELS HAVE
GENERALLY BEEN TOO BULLISH WITH STORM DEVELOPMENT/COVERAGE THE
PAST FEW DAYS...BUT WEAK SIGNALS ARE THERE FOR POSSIBLE ISOLATED
ACTIVITY LATER TODAY. KEPT HIGHS CLOSE TO PREVIOUS FORECAST...
IN THE MID AND UPPER 90S.
THE 00Z GFS DEVELOPED MORE PCPN OVERNIGHT ALONG THE KS/NE BORDER
BUT FELT THAT WAS OVERDONE AT THIS POINT. HAVE MOST OF THE AREA
DRY OVERNIGHT WITH LOWS IN THE MID OR UPPER 60S NORTH AND LOWER
70S SOUTH. RIGHT NOW...TUESDAY LOOKS TO BE A FEW DEGREES COOLER
THAN TODAY...WITH HEAT INDICES STAYING MAINLY BELOW 100.
RAIN CHANCES START TO INCREASE TUESDAY NIGHT AND THEN MORE ON
WEDNESDAY AS HEIGHTS DECREASE A BIT. THIS WILL ALLOW SHORTWAVE
ENERGY TO MOVE OUT OF THE WESTERN UNITED STATES TROUGH AND TAP
INTO SOME MONSOONAL MOISTURE. DUE TO MORE CLOUD COVER...HAVE
HIGHS WEDNESDAY MAINLY 85 TO 90.
.LONG TERM...(WEDNESDAY NIGHT THROUGH SUNDAY)
ISSUED AT 310 AM CDT MON JUL 13 2015
500 MB RIDGE WILL GENERALLY REMAIN CENTERED OVER LA OR ERN TX
THROUGH THIS PERIOD. OUR AREA WILL BE MOSTLY IN SOUTHWEST MID
LEVEL FLOW...AHEAD OF THE TROUGH LOCATED MAINLY ACROSS THE PACIFIC
NORTHWEST. TEMPERATURES WILL GENERALLY BE SEASONAL WITH OCCASIONAL
SMALL CHANCES FOR PCPN. BEST CHANCES LOOK TO BE WEDNESDAY NIGHT
INTO THURSDAY AND THEN AGAIN SUNDAY NIGHT.
&&
.AVIATION...(12Z TAFS FOR KOFK...KLNK AND KOMA.)
ISSUED AT 631 AM CDT MON JUL 13 2015
VFR CONDITIONS THROUGH THE TAF PERIOD. ISOLATED THUNDERSTORMS
EARLY THIS MORNING AT KOMA WITH CIGS BKN FL060-100. NOT SURE IF
THESE WILL MAKE IT TO KLNK...SO WILL MENTION SHOWERS EARLY AND
MONITOR FOR ANY OTHER POP UPS WITH THE COLD FRONT SLIPPING SOUTH
TODAY. SOME GUSTY WINDS POSSIBLE NEAR THE SHOWERS AND STORMS. NORTHWEST
WINDS TO INCREASE TO 10 TO 15KTS THIS MORNING AND THEN DIMINISH TO
LIGHT AND VARIABLE THIS EVENING.
&&
.OAX WATCHES/WARNINGS/ADVISORIES...
NE...HEAT ADVISORY FROM 1 PM THIS AFTERNOON TO 8 PM CDT THIS EVENING
FOR NEZ045-051>053-066>068-078-088>093.
IA...HEAT ADVISORY FROM 1 PM THIS AFTERNOON TO 8 PM CDT THIS EVENING
FOR IAZ055-056-069-079-080-090-091.
&&
$$
SHORT TERM...MILLER
LONG TERM...MILLER
AVIATION...ZAPOTOCNY
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
653 AM EDT MON JUL 13 2015
.SYNOPSIS...
AN INLAND TROUGH AND HIGH PRESSURE OFFSHORE WILL PROVIDE A
CHANCE OF SHOWERS AND THUNDERSTORM EACH DAY THROUGH MID WEEK. A FEW
THUNDERSTORMS COULD BECOME STRONG TO SEVERE EACH AFTERNOON...
ESPECIALLY LATER TUESDAY AS LOW PRESSURE DEEPENS OVER THE AREA.
DRIER WEATHER WILL DEVELOP ON THURSDAY BUT A RETURN TO MORE HUMID
WEATHER WILL RETURN DURING THE WEEKEND.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 640 AM MONDAY...LONGWAVE UPPER PATTERN IS PRETTY MUCH SET
FOR THE REMAINDER OF THIS WEEK...WITH UPPER RIDGING ACROSS THE
MID- SECTION OF THE U.S. AND UPPER TROFFING LYING JUST OFF THE
MID- ATLANTIC AND SOUTHEAST COASTS. THIS LEAVES THE FORECAST AREA
UNDER THE INFLUENCE OF NW FLOW ALOFT...ACCOMPANIED BY THE
OCCASIONAL S/W TROF OR VORT DROPPING SOUTHEAST AFFECTING ALL OR
PORTIONS OF THE FA THIS PERIOD...AND SUBSEQUENT PERIODS THERE-
AFTER.
AT THE MOMENT...THE FA IS UNDER THE INFLUENCE OF A MID-LEVEL S/W
TROF EMBEDDED IN THIS UPPER NW FLOW. THE BEST DYNAMICS ACCORDING TO
THE RAP WILL STAY NORTH OF THE FA. ENOUGH JUICE IE. CAPE AND
MOISTURE IDENTIFIED BY MODEL SOUNDINGS REMAINS AVAILABLE FOR
CONVECTION THIS MORNING...MAINLY IN THE FORM OF SHOWERS. ITS NOT
UNTIL A FEW HRS AFTER DAYBREAK THAT MODEL SOUNDINGS INDICATE A MORE
FAVORABLE PROFILE...IE. INCREASING CAPE DUE TO THE DAYS
INSOLATION...FOR THUNDERSTORMS TO OCCUR. FOR THIS AFTERNOON AND
EVENING...MODELS...ESPECIALLY THE NAM...INDICATE SOME NVA SUBSIDENCE
ALOFT TO PUSH ACROSS THE FA IN THE WAKE OF THIS CURRENT MID-LEVEL
S/W TROF. WILL LEAN TOWARDS THE NAM...AND TONE DOWN THE POPS ACROSS
THE FA...ESPECIALLY ACROSS THE ILM SC COUNTIES. BEAR IN MIND STILL
THE THREAT FOR CONVECTION JUST NOT AS PRONOUNCED AS THE HRS LEADING
UP TO THIS AFTERNOON. SFC CONVERGENCE ALONG THE DEEPENING SFC TROF
ACROSS THE EASTERN CAROLINAS WILL AID THE CONTINUED LOW THREAT OF
CONVECTION THIS AFTN AND EVENING.
FOR THE LATE EVENING HOURS INTO THE PRE-DAWN HRS OF TUE...THE FA
ONCE AGAIN BECOMES UNDER THE INFLUENCE OF A MID-LEVEL S/W
TROF...WITH THE BEST DYNAMICS FROM THIS FEATURE AFFECTING MAINLY THE
ILM NC PORTIONS OF THE FA AND FURTHER NORTHWARD. HAVE INCREASED POPS
DURING THIS TIME PERIOD...HIER ACROSS THE ILM NC CWA. THERE IS A
POSSIBILITY THAT A NOCTURNAL MCS/MCC MAY DEVELOP UPSTREAM AND
EVENTUALLY DROP TO THE SOUTHEAST AND AFFECT THE FA LATE TONIGHT.
FOR MAX/MIN TEMPS...DID A BLEND OF AVBL MOS GUIDANCE. FOR MAX TEMPS
ONLY...LOWERED THIS BLEND BY A DEGREE OR 2 AS A RESULT OF MORE
WIDESPREAD OPAQUE CLOUDINESS AND THE SHRA/TSRA THREAT.
&&
.SHORT TERM /TUESDAY THROUGH WEDNESDAY NIGHT/...
AS OF 340 AM MONDAY...ACTIVE PERIOD OF WEATHER EXPECTED TUESDAY INTO
WEDNESDAY...WITH AN ENHANCED RISK FOR SEVERE WEATHER HIGHLIGHTED BY
THE STORM PREDICTION CENTER ACROSS OUR WEST/NORTHWEST FORECAST AREA
TUESDAY. DURING TUESDAY STRONGER IMPULSES WILL APPROACH IN THE
NORTHWEST FLOW ALOFT WHILE AN H3 JET NOSES INTO THE CAROLINAS AS AN
INLAND SURFACE TROUGH STRENGTHENS. STRONG INSTABILITY IS EXPECTED
WITH BREEZY SOUTH-SOUTHWESTERLY FLOW PREVAILING EAST OF THE TROUGH.
THE PRESSURE GRADIENT WILL LIKELY LEAD TO A SEGMENTED RESULTANT
BOUNDARY ALONG THE COAST. OVERALL...THE PATTERN WILL SUPPORT
VEERING/INCREASING WINDS WITH HEIGHT AND SUBSEQUENT HELICITY IN
EXCESS OF 300 M2/S2 ACROSS INLAND AREAS. AS A RESULT...THINK THE
PRIMARY SEVERE WEATHER THREAT LATER TUESDAY WILL BE FROM DAMAGING
WINDS WITH SOME LARGE HAIL POSSIBLE...AND GIVEN THE AFOREMENTIONED
HELICITY CAN/T RULE OUT TORNADOES.
DURING WEDNESDAY...THE SURFACE TROUGH REMAINS INLAND WHILE THE H5
SHORT WAVE TROUGH WILL BEGIN SHIFTING OFF THE MID-ATLANTIC AND
CAROLINA COASTS DURING THE EVENING. THE PASSAGE OF THIS FEATURE
LEADS TO HIGHER CONFIDENCE THAT THE SURFACE BOUNDARY WILL FINALLY
PUSH OFF THE COAST LATE WEDNESDAY NIGHT. INSTABILITY MAY BE LOWER
COMPARED TO TUESDAY PER BUFKIT DURING WEDNESDAY...HOWEVER
ENOUGH WILL EXISTS ALONG WITH DECENT PRECIPITABLE WATER AND SUPPORT
ALOFT TO CONTINUE GOOD CHANCE SHOWERS/TSTMS. A FEW OF THESE STORMS
MAY BECOME STRONG TO SEVERE AS WELL. POPS WILL TREND LOWER WEDNESDAY
NIGHT AS THE TROUGH PUSHES FARTHER EAST. MAV MAX TEMPERATURES
WEDNESDAY MAY BE ON THE HIGH SIDE GIVEN THE COVERAGE OF STORMS
EXPECTED.
&&
.LONG TERM /THURSDAY THROUGH SUNDAY/...
AS OF 340 AM MONDAY...THE H5 SHORTWAVE TROUGH WILL BE OFF THE MID-
ATLANTIC COAST EARLY THURSDAY...WHILE AT THE SURFACE THE TROUGH WILL
SHIFT OFFSHORE AS WEAK LOW PRESSURE EVOLVES OFF THE OUTER BANKS. THE
GFS HAS TRENDED TOWARD THIS SOLUTION OVER THE LAST DAY AND
CONFIDENCE IS INCREASING THAT THE PRECIPITABLE WATER WILL LOWER AND
THE BEST SURFACE FORCING WILL REMAIN OFFSHORE ASSOCIATED WITH THE
TROUGH DURING THURSDAY. AS A RESULT...LOWERED MAX TEMPERATURES A
CATEGORY AND LOWERED POPS AS WELL. BY FRIDAY NIGHT THE MID/UPPER
SUBTROPICAL RIDGE WILL BEGIN DRIFTING BACK TO THE WEST FROM THE MS
VALLEY ALLOWING A WEAK TROUGH TO BECOME RE-ESTABLISHED ACROSS THE
EAST COAST THIS WEEKEND. MEX GUIDANCE HAS TRENDED COOLER LIKELY
SINCE THE SURFACE FLOW IS ONSHORE...VERSUS THE HUMID SOUTHWEST FLOW
WE HAVE EXPERIENCED MULTIPLE DAYS THIS SUMMER. THUS...LOWERED MAX
TEMPS THIS WEEKEND...HOWEVER IN THE END MAX TEMPS MAY NEED TO BE
LOWERED ANOTHER CATEGORY OR TWO IF BETTER CONSISTENCY DEVELOPS IN
UPCOMING MODEL RUNS.
&&
.AVIATION /12Z MONDAY THROUGH FRIDAY/...
AS OF 12Z...A SERIES OF WEAK PERTURBATION WILL MOVE THROUGH IN THE
NORTHWEST FLOW OVER THE NEXT SEVERAL DAYS. TIMING OF THE CONVECTION
WILL BE DIFFICULT...WITH BEST CHANCES IN THE AFTERNOON. FLO IS
CURRENTLY IN IFR CONDITIONS...WHICH SHOULD MIX UP TO MVFR BY 14Z. WE
SHOULD GENERATE SOME DECENT CAPE THIS AFTERNOON...WITH ABOUT 25 KTS
OF SHEAR THIS COULD STIR UP SOME GOOD STORMS WITH BRIEF IFR
CONDITIONS AND GUSTY WINDS POSSIBLE.
EXTENDED OUTLOOK...POTENTIAL FOR BRIEF PERIODS OF MVFR IN
SHRA/TSRA. OTHERWISE EXPECT VFR.
&&
.MARINE...
NEAR TERM /THROUGH TONIGHT/...
AS OF 640 AM MONDAY...THE STORY FOR THIS PERIOD WILL BE THE
INCREASING SSW TO SW WINDS ACROSS THE AREA WATERS FROM MIDDAY THRU
TONIGHT...AND INTO SUBSEQUENT PERIODS. THIS A RESULT OF THE SFC PG
TIGHTENING BETWEEN AN AMPLIFIED NE-SW ORIENTED SFC TROF ACROSS THE
EAST-CENTRAL CAROLINAS...AND STRONG RIDGING FROM HIGH PRESSURE
CENTERED OVER THE HIGH SEAS WELL OUT IN THE ATLANTIC. LOOK FOR
WIND SPEEDS TO INCREASE TO AROUND 15 KT LATER THIS AFTERNOON...AND
FURTHER INCREASE TO A SOLID 15 TO 20 KT WITH POSSIBLE GUSTS UP TO
25 KT LATER TONIGHT. THE GUSTS IN PART FROM A 30+ KT LOW LEVEL JET
OCCURRING OVER THE AREA WATERS...VIA VARIOUS MODEL SOUNDINGS FOR
FRYING PAN SHOALS.
SIGNIFICANT SEAS WILL INITIALLY RUN AROUND 2 FT THRUOUT...THEN BEGIN
BUILDING TO AROUND 3 FT BY EARLY THIS EVENING...AND THEN FURTHER
BUILD TO 3 TO 5 FT THRUOUT BY LATE THIS EVENING AND THRU THE PRE-
DAWN TUE HOURS. A LAZY ESE 1 TO 1.5 FOOT GROUND SWELL WILL INITIALLY
DOMINATE THE SIG. SEAS. AS WINDS INCREASE...LOOK FOR LOCALLY
PRODUCED WIND DRIVEN WAVES AT 4 TO 5 SECOND PERIODS TO DOMINATE
LATE THIS AFTERNOON AND DEFINITELY DURING TONIGHT.
SHORT TERM /TUESDAY THROUGH WEDNESDAY NIGHT/...
AS OF 340 AM MONDAY...MARGINAL SMALL CRAFT CONDITIONS ARE POSSIBLE
TUESDAY AFTERNOON INTO WEDNESDAY AS A RESULT OF A TIGHTENED PRESSURE
GRADIENT AND RESULTANT SOUTHWEST FETCH. WIND WAVES WILL DOMINANT
DURING THIS PERIOD AS WELL AS THE BULK OF THE SPECTRAL WAVE ENERGY
IS FOCUSED IN THE 5-6 SEC RANGE. SIGNIFICANT WAVE HEIGHTS WILL BE IN
THE 3-5 FT WITHIN 10 NM AND POSSIBLE 5-6 FOOTERS ACROSS THE OUTER
WATERS. SEAS WILL SLOWLY SUBSIDE LATE WEDNESDAY NIGHT AS THE SURFACE
TROUGH PUSHES OFF THE COAST ALLOWING THE SOUTHWEST FETCH TO WEAKEN
AND VEER WITH ITS PASSAGE.
LONG TERM MARINE/THURSDAY THROUGH FRIDAY/
AS OF 340 AM MONDAY...INCREASING CONFIDENCE THAT THE SURFACE TROUGH
WILL SHIFT ACROSS THE WATERS BY THURSDAY MORNING AS WEAK LOW
PRESSURE EXISTS OFF THE OUTER BANKS. AS THIS COMES TO FRUITION THE
RATHER LIGHT FLOW WILL BECOME OFFSHORE...THEN VEER TO A LIGHT
NORTHEAST FLOW AS THE LOW EXITS TO THE NORTHEAST DURING THE EARLY
AFTERNOON. AS A WEAK RIDGE BUILDS IN FROM THE NORTHEAST THE
NORTHEAST TO EAST FLOW WILL PERSIST THROUGH FRIDAY. THINK CHANCES
FOR SHOWERS/TSTMS WILL DECREASE THURSDAY...WITH A FEW STORMS
POSSIBLE FRIDAY.
&&
.ILM WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
NC...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...SRP
NEAR TERM...DCH
SHORT TERM...SRP
LONG TERM...SRP
AVIATION...DL
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
608 EDT MON JUL 13 2015
.SYNOPSIS...
AN INLAND TROUGH AND HIGH PRESSURE OFFSHORE WILL PROVIDE A
CHANCE OF SHOWERS AND THUNDERSTORM EACH DAY THROUGH MID WEEK. A FEW
THUNDERSTORMS COULD BECOME STRONG TO SEVERE EACH AFTERNOON...
ESPECIALLY LATER TUESDAY AS LOW PRESSURE DEEPENS OVER THE AREA.
DRIER WEATHER WILL DEVELOP ON THURSDAY BUT A RETURN TO MORE HUMID
WEATHER WILL RETURN DURING THE WEEKEND.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 340 AM MONDAY...LONGWAVE UPPER PATTERN IS PRETTY MUCH SET FOR
THE REMAINDER OF THIS WEEK...WITH UPPER RIDGING ACROSS THE MID-
SECTION OF THE U.S. AND UPPER TROFFING LYING JUST OFF THE MID-
ATLANTIC AND SOUTHEAST COASTS. THIS LEAVES THE FORECAST AREA UNDER
THE INFLUENCE OF NW FLOW ALOFT...ACCOMPANIED BY THE OCCASIONAL S/W
TROF OR VORT DROPPING SOUTHEAST AFFECTING ALL OR PORTIONS OF THE FA
THIS PERIOD...AND SUBSEQUENT PERIODS THERE-AFTER.
AT THE MOMENT...THE FA IS UNDER THE INFLUENCE OF A MID-LEVEL S/W
TROF EMBEDDED IN THIS UPPER NW FLOW. THE BEST DYNAMICS ACCORDING TO
THE RAP WILL STAY NORTH OF THE FA. ENOUGH JUICE IE. CAPE AND
MOISTURE IDENTIFIED BY MODEL SOUNDINGS REMAINS AVAILABLE FOR
CONVECTION THIS MORNING...MAINLY IN THE FORM OF SHOWERS. ITS NOT
UNTIL A FEW HRS AFTER DAYBREAK THAT MODEL SOUNDINGS INDICATE A MORE
FAVORABLE PROFILE...IE. INCREASING CAPE DUE TO THE DAYS
INSOLATION...FOR THUNDERSTORMS TO OCCUR. FOR THIS AFTERNOON AND
EVENING...MODELS...ESPECIALLY THE NAM...INDICATE SOME NVA SUBSIDENCE
ALOFT TO PUSH ACROSS THE FA IN THE WAKE OF THIS CURRENT MID-LEVEL
S/W TROF. WILL LEAN TOWARDS THE NAM...AND TONE DOWN THE POPS ACROSS
THE FA...ESPECIALLY ACROSS THE ILM SC COUNTIES. BEAR IN MIND STILL
THE THREAT FOR CONVECTION JUST NOT AS PRONOUNCED AS THE HRS LEADING
UP TO THIS AFTERNOON. SFC CONVERGENCE ALONG THE DEEPENING SFC TROF
ACROSS THE EASTERN CAROLINAS WILL AID THE CONTINUED LOW THREAT OF
CONVECTION THIS AFTN AND EVENING.
FOR THE LATE EVENING HOURS INTO THE PRE-DAWN HRS OF TUE...THE FA
ONCE AGAIN BECOMES UNDER THE INFLUENCE OF A MID-LEVEL S/W
TROF...WITH THE BEST DYNAMICS FROM THIS FEATURE AFFECTING MAINLY THE
ILM NC PORTIONS OF THE FA AND FURTHER NORTHWARD. HAVE INCREASED POPS
DURING THIS TIME PERIOD...HIER ACROSS THE ILM NC CWA. THERE IS A
POSSIBILITY THAT A NOCTURNAL MCS/MCC MAY DEVELOP UPSTREAM AND
EVENTUALLY DROP TO THE SOUTHEAST AND AFFECT THE FA LATE TONIGHT.
FOR MAX/MIN TEMPS...DID A BLEND OF AVBL MOS GUIDANCE. FOR MAX TEMPS
ONLY...LOWERED THIS BLEND BY A DEGREE OR 2 AS A RESULT OF MORE
WIDESPREAD OPAQUE CLOUDINESS AND THE SHRA/TSRA THREAT.
&&
.SHORT TERM /TUESDAY THROUGH WEDNESDAY NIGHT/...
AS OF 340 AM MONDAY...ACTIVE PERIOD OF WEATHER EXPECTED TUESDAY INTO
WEDNESDAY...WITH AN ENHANCED RISK FOR SEVERE WEATHER HIGHLIGHTED BY
THE STORM PREDICTION CENTER ACROSS OUR WEST/NORTHWEST FORECAST AREA
TUESDAY. DURING TUESDAY STRONGER IMPULSES WILL APPROACH IN THE
NORTHWEST FLOW ALOFT WHILE AN H3 JET NOSES INTO THE CAROLINAS AS AN
INLAND SURFACE TROUGH STRENGTHENS. STRONG INSTABILITY IS EXPECTED
WITH BREEZY SOUTH-SOUTHWESTERLY FLOW PREVAILING EAST OF THE TROUGH.
THE PRESSURE GRADIENT WILL LIKELY LEAD TO A SEGMENTED RESULTANT
BOUNDARY ALONG THE COAST. OVERALL...THE PATTERN WILL SUPPORT
VEERING/INCREASING WINDS WITH HEIGHT AND SUBSEQUENT HELICITY IN
EXCESS OF 300 M2/S2 ACROSS INLAND AREAS. AS A RESULT...THINK THE
PRIMARY SEVERE WEATHER THREAT LATER TUESDAY WILL BE FROM DAMAGING
WINDS WITH SOME LARGE HAIL POSSIBLE...AND GIVEN THE AFOREMENTIONED
HELICITY CAN/T RULE OUT TORNADOES.
DURING WEDNESDAY...THE SURFACE TROUGH REMAINS INLAND WHILE THE H5
SHORT WAVE TROUGH WILL BEGIN SHIFTING OFF THE MID-ATLANTIC AND
CAROLINA COASTS DURING THE EVENING. THE PASSAGE OF THIS FEATURE
LEADS TO HIGHER CONFIDENCE THAT THE SURFACE BOUNDARY WILL FINALLY
PUSH OFF THE COAST LATE WEDNESDAY NIGHT. INSTABILITY MAY BE LOWER
COMPARED TO TUESDAY PER BUFKIT DURING WEDNESDAY...HOWEVER
ENOUGH WILL EXISTS ALONG WITH DECENT PRECIPITABLE WATER AND SUPPORT
ALOFT TO CONTINUE GOOD CHANCE SHOWERS/TSTMS. A FEW OF THESE STORMS
MAY BECOME STRONG TO SEVERE AS WELL. POPS WILL TREND LOWER WEDNESDAY
NIGHT AS THE TROUGH PUSHES FARTHER EAST. MAV MAX TEMPERATURES
WEDNESDAY MAY BE ON THE HIGH SIDE GIVEN THE COVERAGE OF STORMS
EXPECTED.
&&
.LONG TERM /THURSDAY THROUGH SUNDAY/...
AS OF 340 AM MONDAY...THE H5 SHORTWAVE TROUGH WILL BE OFF THE MID-
ATLANTIC COAST EARLY THURSDAY...WHILE AT THE SURFACE THE TROUGH WILL
SHIFT OFFSHORE AS WEAK LOW PRESSURE EVOLVES OFF THE OUTER BANKS. THE
GFS HAS TRENDED TOWARD THIS SOLUTION OVER THE LAST DAY AND
CONFIDENCE IS INCREASING THAT THE PRECIPITABLE WATER WILL LOWER AND
THE BEST SURFACE FORCING WILL REMAIN OFFSHORE ASSOCIATED WITH THE
TROUGH DURING THURSDAY. AS A RESULT...LOWERED MAX TEMPERATURES A
CATEGORY AND LOWERED POPS AS WELL. BY FRIDAY NIGHT THE MID/UPPER
SUBTROPICAL RIDGE WILL BEGIN DRIFTING BACK TO THE WEST FROM THE MS
VALLEY ALLOWING A WEAK TROUGH TO BECOME RE-ESTABLISHED ACROSS THE
EAST COAST THIS WEEKEND. MEX GUIDANCE HAS TRENDED COOLER LIKELY
SINCE THE SURFACE FLOW IS ONSHORE...VERSUS THE HUMID SOUTHWEST FLOW
WE HAVE EXPERIENCED MULTIPLE DAYS THIS SUMMER. THUS...LOWERED MAX
TEMPS THIS WEEKEND...HOWEVER IN THE END MAX TEMPS MAY NEED TO BE
LOWERED ANOTHER CATEGORY OR TWO IF BETTER CONSISTENCY DEVELOPS IN
UPCOMING MODEL RUNS.
&&
.AVIATION /12Z MONDAY THROUGH FRIDAY/...
AS OF 12Z...A SERIES OF WEAK PERTURBATION WILL MOVE THROUGH IN THE
NORTHWEST FLOW OVER THE NEXT SEVERAL DAYS. TIMING OF THE CONVECTION
WILL BE DIFFICULT...WITH BEST CHANCES IN THE AFTERNOON. FLO IS
CURRENTLY IN IFR CONDITIONS...WHICH SHOULD MIX UP TO MVFR BY 14Z. WE
SHOULD GENERATE SOME DECENT CAPE THIS AFTERNOON...WITH ABOUT 25 KTS
OF SHEAR THIS COULD STIR UP SOME GOOD STORMS WITH BRIEF IFR
CONDITIONS AND GUSTY WINDS POSSIBLE.
EXTENDED OUTLOOK...POTENTIAL FOR BRIEF PERIODS OF MVFR IN
SHRA/TSRA. OTHERWISE EXPECT VFR.
&&
.MARINE...
NEAR TERM /THROUGH TONIGHT/...
AS OF 340 AM MONDAY...THE STORY FOR THIS PERIOD WILL BE THE
INCREASING SSW TO SW WINDS ACROSS THE AREA WATERS FROM MIDDAY THRU
TONIGHT...AND INTO SUBSEQUENT PERIODS. THIS A RESULT OF THE SFC PG
TIGHTENING BETWEEN AN AMPLIFIED NE-SW ORIENTED SFC TROF ACROSS THE
EAST-CENTRAL CAROLINAS...AND STRONG RIDGING FROM HIGH PRESSURE
CENTERED OVER THE HIGH SEAS WELL OUT IN THE ATLANTIC. LOOK FOR WIND
SPEEDS TO INCREASE TO AROUND 15 KT LATER THIS AFTERNOON...AND
FURTHER INCREASE TO A SOLID 15 TO 20 KT WITH POSSIBLE GUSTS UP TO 25
KT LATER TONIGHT. THE GUSTS IN PART FROM A 30+ KT LOW LEVEL JET
OCCURRING OVER THE AREA WATERS...VIA VARIOUS MODEL SOUNDINGS FOR
FRYING PAN SHOALS.
SIGNIFICANT SEAS WILL INITIALLY RUN AROUND 2 FT THRUOUT...THEN BEGIN
BUILDING TO AROUND 3 FT BY EARLY THIS EVENING...AND THEN FURTHER
BUILD TO 3 TO 5 FT THRUOUT BY LATE THIS EVENING AND THRU THE PRE-
DAWN TUE HOURS. A LAZY ESE 1 TO 1.5 FOOT GROUND SWELL WILL INITIALLY
DOMINATE THE SIG. SEAS. AS WINDS INCREASE...LOOK FOR LOCALLY
PRODUCED WIND DRIVEN WAVES AT 4 TO 5 SECOND PERIODS TO DOMINATE
LATE THIS AFTERNOON AND DEFINITELY DURING TONIGHT.
SHORT TERM /TUESDAY THROUGH WEDNESDAY NIGHT/...
AS OF 340 AM MONDAY...MARGINAL SMALL CRAFT CONDITIONS ARE POSSIBLE
TUESDAY AFTERNOON INTO WEDNESDAY AS A RESULT OF A TIGHTENED PRESSURE
GRADIENT AND RESULTANT SOUTHWEST FETCH. WIND WAVES WILL DOMINANT
DURING THIS PERIOD AS WELL AS THE BULK OF THE SPECTRAL WAVE ENERGY
IS FOCUSED IN THE 5-6 SEC RANGE. SIGNIFICANT WAVE HEIGHTS WILL BE IN
THE 3-5 FT WITHIN 10 NM AND POSSIBLE 5-6 FOOTERS ACROSS THE OUTER
WATERS. SEAS WILL SLOWLY SUBSIDE LATE WEDNESDAY NIGHT AS THE SURFACE
TROUGH PUSHES OFF THE COAST ALLOWING THE SOUTHWEST FETCH TO WEAKEN
AND VEER WITH ITS PASSAGE.
LONG TERM MARINE/THURSDAY THROUGH FRIDAY/
AS OF 340 AM MONDAY...INCREASING CONFIDENCE THAT THE SURFACE TROUGH
WILL SHIFT ACROSS THE WATERS BY THURSDAY MORNING AS WEAK LOW
PRESSURE EXISTS OFF THE OUTER BANKS. AS THIS COMES TO FRUITION THE
RATHER LIGHT FLOW WILL BECOME OFFSHORE...THEN VEER TO A LIGHT
NORTHEAST FLOW AS THE LOW EXITS TO THE NORTHEAST DURING THE EARLY
AFTERNOON. AS A WEAK RIDGE BUILDS IN FROM THE NORTHEAST THE
NORTHEAST TO EAST FLOW WILL PERSIST THROUGH FRIDAY. THINK CHANCES
FOR SHOWERS/TSTMS WILL DECREASE THURSDAY...WITH A FEW STORMS
POSSIBLE FRIDAY.
&&
.ILM WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
NC...NONE.
MARINE...NONE.
&&
$$
NEAR TERM...DCH
SHORT TERM...SRP
LONG TERM...SRP
AVIATION...43
AREA FORECAST DISCUSSION
NWS PUEBLO CO
315 PM MDT MON JUL 13 2015
.SHORT TERM...(THIS EVENING THROUGH TUESDAY)
ISSUED AT 235 PM MDT MON JUL 13 2015
UPR HIGH PRESSURE IS CENTERED ABOUT OVR CENTRAL TX TODAY...WITH A
PLUME OF SUB TROPICAL MSTR WORKING ITS WAY AROUND THE BACK SIDE OF
THE UPR HIGH AND INTO CO. AS A RESULT...ISOLD TO SCT SHOWERS AND
TSTMS ARE EXPECTED ACRS THE FORECAST AREA THIS EVENING. AREAS OVR
AND NR THE MTNS SHOULD HAVE THE HIGHEST COVERAGE OF PCPN THIS
EVENING. MUCH OF THE CONVECTIVE ACTIVITY IS EXPECTED TO END BY
AROUND MIDNIGHT...BUT THE NAM AND HRRR INDICATE THE POSSIBILITY OF
SOME ISOLD ACTIVITY CONTINUING THRU THE LATE NIGHT HOURS AND INTO
TUE MORNING.
ON TUE THE UPR HIGH CENTER IS FORECAST TO SHIFT EASTWARD AND BECOME
CENTERED OVR ERN TX AS AN UPR TROF MOVES OVR THE WRN STATES. THE
PLUME OF MSTR WL CONTINUE STREAMING OVR THE AREA ON TUE...AND THERE
WL BE ANOTHER ROUND OF SCT SHOWERS AND TSTMS ACRS MUCH OF THE
FORECAST AREA...MAINLY IN THE AFTERNOON AND EVENING HOURS. LATEST
NAM SHOWS DEW POINTS TUE AFTERNOON IN THE MID OR UPR 40S ALONG THE I-
25 CORRIDOR AND IN THE MID TO UPR 50S NR THE KS BORDER. CAPE VALUES
LOOK FAIRLY LOW OVR MUCH OF THE AREA TUE AFTERNOON ALONG WITH WEAK
DEEP LAYER SHEAR...HOWEVER NR THE KS BORDER 1000-2000 J/KG IS
FORECAST WITH 0-6 KM SHEAR OF 35 TO 40 KTS. AS A RESULT...SPC HAS
THE SOUTHEAST PLAINS IN THE MARGINAL RISK AREA FOR SEVERE STORMS ON
TUE.
.LONG TERM...(TUESDAY NIGHT THROUGH MONDAY)
ISSUED AT 235 PM MDT MON JUL 13 2015
MODELS IN DECENT AGREEMENT THROUGH THE FIRST HALF OF THE EXTENDED
PERIOD WITH DIFFERENCE AMONG THE VARIOUS OPERATIONAL SOLUTIONS AND
HIGH ENSEMBLE SPREADS THIS COMING WEEKEND INTO EARLY NEXT WEEK.
TUESDAY NIGHT THROUGH WEDNESDAY...THE UPPER PATTERN WILL FEATURE
HIGH PRESSURE OVER THE SOUTHEAST CONUS WHILE AN UPPER TROUGH SITS
OVER THE PACIFIC NORTHWEST. TWO STRONG WAVES ARE FORECAST TO MOVE
OUT OF THE DESERT SOUTHWEST AND ACROSS COLORADO. THE FIRST WILL BE
LIFTING ACROSS THE ROCKIES TUESDAY EVENING...WITH WIDESPREAD
SHOWERS AND THUNDERSTORMS OVER THE MOUNTAINS EARLY...SPREADING
EAST THROUGH THE OVERNIGHT HOURS. THERE ARE MODEL DIFFERENCES WITH
THE GFS DEVELOPING AN MCS OVER THE PALMER DIVIDE AND LIFTING IT
INTO NORTHEAST COLORADO...WHILE THE NAM DEVELOPS AN MCS AND TRACKS
IT EAST ACROSS OUR EASTERN PLAINS. HEAVY RAIN WILL BE POSSIBLE
ALONG WITH THE THREAT OF FLOODING...INITIALLY OVER THE MOUNTAINS
AND THEN OVER THE PLAINS. HEAVIER RAIN FOR THE PLAINS WILL BE
HIGHLY DEPENDENT ON WHERE THE MCS TRACKS.
ANOTHER WAVE IS FORECAST TO LIFT NORTHEAST ACROSS COLORADO ON
WEDNESDAY AFTERNOON. EXPECT ANOTHER ROUND SHOWERS AND
THUNDERSTORMS BY WEDNESDAY AFTERNOON WITH INITIAL DEVELOPMENT OVER
THE MOUNTAINS. AGAIN...ABUNDANT MOISTURE WILL LEAD TO AREAS OF
HEAVY RAINFALL UNDER STRONGER STORMS. MODELS PUSH THE ACTIVITY
EAST OFF THE MOUNTAINS AND ACROSS THE PLAINS WEDNESDAY EVENING AND
OVERNIGHT. THERE IS THE POTENTIAL OF ANOTHER MCS DEVELOPING...WITH
MODEL SOLUTIONS FOCUSING IT OVER THE FAR SOUTHEASTERN COUNTIES
WEDNESDAY NIGHT.
THURSDAY THROUGH SATURDAY...AN UPPER LEVEL LOW IS FORECAST TO
DEVELOP OVER THE PACIFIC NORTHWEST HELPING TO AMPLIFY AND DRAW THE
HIGH PRESSURE OVER THE SOUTHEAST CONUS TO THE WEST. THIS WILL
FORCE THE MAIN MOISTURE PLUME AND ENERGY IN THE SOUTHERLY FLOW TO
THE WEST. WEAK ENERGY MOVING THROUGH THE RIDGE WILL HELP BRING
AFTERNOON AND EVENING THUNDERSTORMS TO THE MOUNTAINS EACH DAY.
LOCALLY HEAVY RAINFALL WILL REMAIN POSSIBLE ALONG WITH GUSTY
OUTFLOW WINDS AND LIGHTNING. STEERING FLOWS ALOFT WILL REMAIN WEAK
AND EASTWARD PROGRESSION OFF THE MOUNTAINS LOOKS LIMITED TO THE
PALMER DIVIDE AND I-25 CORRIDOR DURING THE EVENING HOURS BEFORE
DISSIPATING WITH SUNDOWN.
SUNDAY AND MONDAY...MODELS BEGIN TO DIVERGE WITH HIGH ENSEMBLE
SPREADS AND LOWERED CONFIDENCE IN ANY SOLUTION. THE GFS BRINGS THE
PACIFIC NORTHWEST STORM SYSTEM ACROSS THE AREA SUNDAY INTO MONDAY.
THIS WOULD BRING MORE WIDESPREAD SHOWER AND THUNDERSTORM ACTIVITY
ALONG WITH COOLER TEMPERATURES TO THE REGION...ESPECIALLY ON
SUNDAY. THE ECMWF KEEPS THE PATTERN STATUS QUO...WITH THE UPPER
SYSTEM OVER THE PACIFIC NORTHWEST WEAKENING AND THE HIGH PRESSURE
REMAINING OVER TEXAS. THIS WOULD KEEP THE MAIN MOISTURE AND ENERGY
TO THE WEST...WITH CONTINUED DAILY AFTERNOON AND EVENING SHOWER
AND THUNDERSTORM ACTIVITY FOR THE MOUNTAINS...WITH LIMITED
MOVEMENT THROUGH THE EVENING. MOZLEY
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z TUESDAY EVENING)
ISSUED AT 235 PM MDT MON JUL 13 2015
VFR CONDITIONS CAN BE EXPECTED TONIGHT THROUGH TUESDAY. SHOWERS AND
TSTMS WL BE POSSIBLE IN THE VCNTY OF THE TERMINAL FORECAST SITES
THIS EVENING AND AGAIN TUESDAY AFTERNOON. IF TSTMS MOVE INTO THE
VCNTY...THERE WL BE THE POTENTIAL FOR MODERATE TO HEAVY RAIN TO
CAUSE BRIEF MVFR CONDITIONS.
&&
.PUB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...28
LONG TERM...MOZLEY
AVIATION...28
AREA FORECAST DISCUSSION
NWS GRAND JUNCTION CO
314 PM MDT MON JUL 13 2015
.SHORT TERM...(THIS EVENING THROUGH TUESDAY NIGHT)
ISSUED AT 310 PM MDT MON JUL 13 2015
IN SW FLOW A WAVE PASSED LAST NIGHT LEAVING THE FORECAST AREA IN A
SUBSIDENT REGION THROUGH THE MORNING HOURS. PRECIPITABLE WATER
VALUES HAVE ALSO DIMINISHED A BIT THROUGH TODAY WITH NO FAVORABLE
GRADIENT AREAS OVER THE FORECAST AREA. NO ORGANIZED FORCING IS
SEEN FOR THIS LATE AFTERNOON OR OVERNIGHT SO CONVECTION WILL FIRE
OVER HIGHER TERRAIN AND POTENTIALLY DRIFT TO NEARBY VALLEYS TO THE
NE. HRRR SHOWS A QUICK DIMINISHING OF STORM COVERAGE WITH SUNSET
EXCEPT NEAR THE FOUR CORNERS TO SW SAN JUANS WHERE STORMS MAY
PERSIST TO AROUND MIDNIGHT.
TUESDAY...MOISTURE INCREASES A BIT FROM THE SOUTH AND FORCING
INCREASES AS THE RIGHT ENTRANCE QUADRANT OF THE JET PUSHES ACROSS
THE NORTHERN FORECAST AREA THROUGH THE AFTERNOON WITH RESULTING
LOW LEVEL CONVERGENCE DEVELOPING BY LATE AFTERNOON ALONG THE UT-
CO STATE LINE. THE RELATIVELY SLOW STORM MOTION...TO THE NE AT
10KTS...WILL LEAD TO POTENTIAL FLOODING CONCERNS FAVORING EASTERN
UTAH AND FAR WESTERN COLORADO UNDER THE BEST LATE AFTERNOON-
EVENING JET FORCING. SCATTERED STORMS AND SHOWERS ARE EXPECTED TO
PERSIST BEYOND MIDNIGHT.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 310 PM MDT MON JUL 13 2015
WEDNESDAY...THE WESTERN TROUGH PUSHES INTO THE GREAT BASIN
BRINGING A DRIER W-SW FLOW TO EASTERN UTAH. MOST AFTERNOON
SHOWERS AND STORMS WILL BE CONFINED TO WESTERN COLORADO. THE TREND
IS FOR LESS DRYING THAN PROGGED. THE DRYING TREND CONTINUES ON
THURSDAY WHICH MAY BE THE WARMEST DAY OF THE NEW WEEK.
PRECIPITABLE WATER VALUES FALL TO AROUND 0.5 INCH...SO ISOLATED
LATE-DAY STORMS WILL PRODUCE GUSTY WINDS AND LIGHTNING BUT LITTLE
RAIN.
THE NEXT MONSOONAL SURGE BEGINS LATE FRIDAY IN THE GFS WITH ITS
DEEPER WESTERN TROUGH. THE EC DELAYS THE SURGE UNTIL LATE
SATURDAY. SO FOR THIS FORECAST WE SHOWED A WETTER TREND FOR THOSE
DAYS WITH SUNDAY EXPECTED TO HAVE SIGNIFICANTLY MORE STORM
COVERAGE. THE WET PERIOD COULD INTO MONDAY WHEN THE EC BEGINS TO
PULL MOISTURE OFF OF HURRICANE DOLORES INTO THE NORTHERN FORECAST
AREA ACROSS THE TOP OF THE SUBTROPICAL HIGH. THE GFS KEEPS
DOLORES FURTHER OUT TO SEA PERHAPS PULLING MOISTURE INTO THE
NORTHERN CWA BY NEXT WEDNESDAY.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z TUESDAY EVENING)
ISSUED AT 310 PM MDT MON JUL 13 2015
SCATTERED LATE DAY STORMS TO HUG HIGHER TERRAIN AND VALLEY
LOCATIONS TO THE NE. THROUGH 05Z THIS EVENING KEGE KASE KTEX KDRO
HAVE A 40 PERCENT CHANCE OF -TSRA WITH ERRATIC OUTFLOW WINDS AND
CIGS BLO ILS BREAK POINTS. 04Z-18Z STORMS WILL BE ISOLATED AND
CIRCUMNAVIGABLE WITH PREVAILING VFR CONDITIONS. AFT 18Z TUESDAY
ALL TAF SITES HAVE A CHANCE OF -TSRA AND CIGS BLO ILS BREAK
POINTS.
&&
.GJT WATCHES/WARNINGS/ADVISORIES...
CO...NONE.
UT...NONE.
&&
$$
SHORT TERM...JOE
LONG TERM...JOE
AVIATION...JOE
AREA FORECAST DISCUSSION
NWS ALBANY NY
155 PM EDT MON JUL 13 2015
.SYNOPSIS...
HIGH PRESSURE OVER THE REGION WILL WEAKEN TODAY AS A DISTURBANCE
IN THE UPPER LEVELS OF THE ATMOSPHERE APPROACHES FROM THE GREAT
LAKES. AS A RESULT...THERE IS A CHANCE OF SHOWERS AND
THUNDERSTORMS THIS AFTERNOON INTO THE EARLY EVENING. THE CHANCE
FOR SHOWERS AND STORMS CONTINUES TUESDAY THROUGH WEDNESDAY AS A
COLD FRONT APPROACHES FROM THE NORTHWEST AND CROSSES THE AREA.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
BAND OF CLOUDINESS ACROSS THE CENTRAL PART OF THE FORECAST AREA
ASSOCIATED WITH UPPER LEVEL TROUGH. REST OF AREA GENERALLY SUNNY.
ADJUSTED CLOUD COVER TO BE IN LINE WITH CURRENT SATELLITE IMAGE.
CLOUDS WILL INCREASE ACROSS THE FORECAST AREA AS HAZY...HOT AND
HUMID CONDITIONS WILL DEVELOP.
CURRENT TEMPERATURES IN 70S TO NEAR 80 DEGREES. WINDS ARE LIGHT
AND FROM THE SOUTHEAST. MODELS INDICATE WINDS WILL INCREASE FROM
THE SOUTH-SOUTHEAST LATER TODAY AND BECOME BREEZY.
LATEST HRRR SHOWS SCATTERED SHOWERS AND THUNDERSTORMS DEVELOPING
AFTER NOON WITH GREATEST COVERAGE ACROSS THE TACONICS...SOUTHERN
VERMONT...BERKSHIRE COUNTY MA AND THE CATSKILLS. ALSO A FEW
ISOLATED CELLS EXPECTED OVER THE ADIRONDACKS THIS AFTERNOON.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH WEDNESDAY NIGHT/...
THE UPPER LEVEL DISTURBANCE WILL PASS TO OUR SOUTH AND WEST
TUESDAY NIGHT INTO WEDNESDAY. GUIDANCE KEEPS THE UPPER LEVEL
TROUGH POSITIVELY TILTED AND PROGRESSIVE. A COLD FRONT WILL ALSO
APPROACH AND IS EXPECTED TO CROSS THE REGION WEDNESDAY AFTERNOON
AND NIGHT. THIS WILL RESULT IN CHANCES STORMS TUESDAY THROUGH
WEDNESDAY. NO STRONG FORCING WILL BE PRESENT SO STORMS ARE NOT
EXPECTED TO BE STRONG OR SEVERE. THE STORM PREDICTION CENTER ONLY
HAS THE LOCAL AREA UNDER A GENERAL THUNDERSTORMS OUTLOOK.
GUIDANCE DOES INDICATE PWATS VALUES WILL RISE TO 1.5+ INCHES
TUESDAY NIGHT INTO WEDNESDAY AHEAD OF THE COLD FRONT...SO STORMS
WILL BE CAPABLE OF PRODUCING HEAVY DOWNPOURS WHICH COULD CAUSE
SOME URBAN AND POOR DRAINAGE FLOODING. WILL CONTINUE TO H8IGHLIGHT
THIS IN OUR HAZARDOUS WEATHER OUTLOOK.
SEASONABLY WARM TEMPERATURES ARE EXPECTED BOTH TUESDAY AND
WEDNESDAY. TUESDAY NIGHT WILL BE A MILD AND MUGGY NIGHT. HOWEVER
WITH THE PASSAGE OF THE COLD FRONT DRIER AIR WILL BE FILTERED IN
ON A NORTHERLY FLOW FOR WEDNESDAY NIGHT.
&&
.LONG TERM /THURSDAY THROUGH SUNDAY/...
HIGH PRESSURE WILL BE SITUATED OVER THE REGION TO START THE LONG
TERM PERIOD FOR THURSDAY INTO FRIDAY. SKIES WILL BE PARTLY TO MOSTLY
CLEAR WITH NO PRECIP EXPECTED. HIGHS LOOK TO BE IN THE LOW TO MID
80S FOR VALLEY AREAS...AND LOWS WILL BE IN THE 50S FOR THURSDAY
NIGHT...AND 60S FOR FRIDAY NIGHT.
WITH STRONG RIDGING ESTABLISHING ITSELF OVER THE CENTRAL US...THE
NORTHEAST WILL BE SITUATED WITHIN NORTHWEST FLOW ALOFT. THIS WILL
ALLOW A SERIES OF WEAK UPPER LEVEL DISTURBANCES TO MOVE TOWARDS THE
REGION FROM SOUTHERN CANADA. THE TIMING OF THESE SUBTLE FEATURES IS
STILL UNKNOWN...BUT EACH DISTURBANCE WILL ALLOW A CHANCE FOR SOME
SCATTERED SHOWERS AND THUNDERSTORMS...ESP WITHIN PEAK DAYTIME
HEATING OF AFTN INTO THE EARLY EVENING HOURS. POPS START TO RISE
FOR LATE FRIDAY NIGHT...AND WILL ALLOW FOR CHC POPS ON BOTH
SAT/SUNDAY. IT LOOKS LIKE THESE CONDITIONS WILL CONTINUE INTO
EARLY NEXT WEEK AS WELL. IT WON/T BE A WASHOUT BY ANY MEANS...BUT
CAN/T RULE OUT THESE SHOWERS AND THUNDERSTORMS THANKS TO THE
PASSING SHORTWAVE ALOFT.
MAX TEMPS OVER THE WEEKEND WILL GENERALLY BE IN THE MID 80S...WITH
MID 60S FOR LOW TEMPS. IT WILL BE FAIRLY MUGGY AS WELL...WITH
DEWPOINTS WELL INTO THE 60S.
&&
.AVIATION /18Z MONDAY THROUGH SATURDAY/...
MAINLY VFR CONDITIONS EXPECTED AT THE TAF SITES THROUGH 18Z
WEDNESDAY.
RADAR SHOWS SHOWERS AND THUNDERSTORMS OVER THE HIGHER
TERRAIN SURROUNDING THE TAF SITES THIS AFTERNOON. SOME SHOWERS
AND AN ISOLATED THUNDERSTORM ARE POSSIBLE NEAR THE TAF SITES THIS
AFTERNOON. COVERED THIS IN TAFS WITH VCTS.
MODEL SOUNDING SHOW MORNING FOG AND SOME LOW CLOUDS DEVELOPING AT
ALL TAF SITES A COUPLE OF HOURS BEFORE SUNRISE ON TUESDAY...AND
LASTING A FEW HOURS. FOG/LOW CLOUDS SHOULD BURN OFF BY 13Z TUESDAY.
WINDS FORECAST TO BE FROM THE SOUTH TO SOUTHEAST AT 10-15 KTS TODAY.
WINDS BECOMING LIGHT AND VARIABLE TONIGHT...BEFORE INCREASING TO
10 TO 15 KTS FROM THE SOUTH TO SOUTHEAST ON TUESDAY.
OUTLOOK...
TUESDAY NIGHT THROUGH WEDNESDAY: MODERATE OPERATIONAL IMPACT. CHANCE
OF SHRA...TSRA.
WEDNESDAY NIGHT THROUGH FRIDAY: NO OPERATIONAL IMPACT. NO SIG WX.
FRIDAY NIGHT THROUGH SATURDAY: MODERATE OPERATIONAL IMPACT. CHANCE OF
SHRA...TSRA.
&&
.FIRE WEATHER...
HIGH PRESSURE OVER THE REGION WILL WEAKEN TODAY AS A DISTURBANCE
IN THE UPPER LEVELS OF THE ATMOSPHERE APPROACHES FROM THE GREAT
LAKES REGION. AS A RESULT WILL BE CHANCES FOR SHOWERS AND
THUNDERSTORMS THIS AFTERNOON INTO THE EARLY EVENING. WE WILL
HAVE CHANCES FOR STORMS TUESDAY THROUGH WEDNESDAY AS A COLD
FRONT ALSO APPROACHES AND CROSSES THE AREA.
&&
.HYDROLOGY...
THERE ARE CHANCES FOR SHOWERS AND THUNDERSTORMS THIS AFTERNOON
INTO EARLY EVENING AS AN UPPER LEVEL DISTURBANCE APPROACHES FROM
THE GREAT LAKES REGION TODAY. THE DISTURBANCE WILL PASS TO OUR
SOUTH AND WEST TUESDAY NIGHT INTO WEDNESDAY AND A COLD FRONT WILL
APPROACH AND CROSS THE REGION RESULTING IN CHANCES STORMS TUESDAY
THROUGH WEDNESDAY. MODELS INDICATE PWATS VALUES WILL RISE TO 1.5+
INCHES TUESDAY NIGHT INTO WEDNESDAY AHEAD OF THE COLD FRONT...SO
STORMS WILL BE CAPABLE OF PRODUCING HEAVY DOWNPOURS WHICH COULD
CAUSE SOME URBAN AND POOR DRAINAGE FLOODING.
MAINLY DRY WEATHER IS EXPECTED THURSDAY AND FRIDAY WITH OUR NEXT
CHANCES FOR STORMS COMING OVER THE WEEKEND AS A SERIES OF WEAK
UPPER LEVEL DISTURBANCES APPROACH AND CROSS THE REGION.
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...IAA
NEAR TERM...IAA/SND
SHORT TERM...IAA
LONG TERM...FRUGIS
AVIATION...SND
FIRE WEATHER...IAA
HYDROLOGY...IAA
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
349 PM CDT MON JUL 13 2015
.MESOSCALE DISCUSSION...
252 PM CDT
MESOSCALE ENVIRONMENT CONTINUES TO BE MONITORED THIS AFTERNOON
FOR EVIDENCE OF CONVECTION INITIATION. CAP NOTED IN DVN 18Z RAOB
SUGGESTS A LITTLE LATER DEVELOPMENT...WHILE WARM FRONT APPEARS TO BE
EVOLVING FARTHER NORTHEAST INTO NORTHERN IL AND SUGGESTS MORE
THE MORE SUBSTANTIAL RISK MAY EXISTS FARTHER NORTH/EAST.
18Z SOUNDINGS FROM ILX AND DVN DEPICT A STRONG LOW-LEVEL CAP
NEAR/NORTH OF THE WARM FRONT (DVN)...AND EXTREME INSTABILITY (MUCAPE
OF 5300 J/KG AT DVN AND 6600 J/KG AT ILX). BOTH SOUNDINGS DEPICT
STRONG DEEP LAYER BULK SHEAR AROUND 50 KTS. THIS DATA CONTINUES TO
INDICATE A STRONG POTENTIAL FOR SEVERE THUNDERSTORMS...WITH EROSION
OF THE CAP AND TIME AND LOCATION OF INITIATION THE MAIN QUESTION.
FORECAST SOUNDINGS FROM RECENT RAP RUNS DO INDICATE WEAKENING OF THE
CAP THROUGH LATE AFTERNOON IN THE 22-00Z TIME FRAME. SATELLITE DATA
INDICATES ONE MID-LEVEL SHORT WAVE APPEARS TO BE MOVING EAST ACROSS
LAKE MICHIGAN/NORTHERN INDIANA AT 19Z...WITH A COUPLE OF ADDITIONAL
RIPPLES NOTED BACK TOWARD SOUTHEAST MINNESOTA. WITH SOME CONSISTENCY
CONVECTION ALLOWING MODELS...SUCH AS THE HRRR...SUGGEST THAT
CONVECTION INITIATION MAY VERY WELL OCCUR ACROSS PARTS OF SOUTHEAST
MINNESOTA/NORTHEAST IOWA/SOUTHWEST WISCONSIN...WHERE OUR
NORTHEASTWARD DEVELOPING WARM FRONT INTERSECTS A SW-NE SYNOPTIC
TROUGH ACROSS EASTERN IOWA. STORM MODE IS STILL ANTICIPATED TO BE
DISCRETE SUPERCELLS OR CLUSTERS...THOUGH THE LOW LEVEL WIND FIELD
HAS BECOME MORE HOMOGENEOUSLY SOUTHWEST WITH THE WARM FRONT/OLD
OUTFLOW LESS DISTINCT THAN EARLIER. THEREFORE THE INITIAL SEVERE
THREAT STILL LOOKS TO BE DAMAGING WINDS...VERY LARGE HAIL...AND
TORRENTIAL RAINFALL. SOMEWHAT WEAKER 0-1 KM SHEAR AND 0-1 KM SRH
APPEAR TO INDICATE A LOWER TORNADO THREAT...THOUGH WILL STILL
CERTAINLY EXIST WHERE A STORM INTERACTS WITH LOCALLY BACKED FLOW
ALONG ANY LINGERING BOUNDARIES. UPSCALE GROWTH INTO A LINEAR/BOWING
MCS IS STILL ANTICIPATED LATER THIS EVENING...PERHAPS CONGEALING
OVER OUR SOUTHEASTERN CWA BEFORE EXITING INTO INDIANA.
WITH THE WARM FRONT EVOLVING FARTHER NORTHEAST...IT DOES APPEAR THAT
THE SEVERE WEATHER THREAT REMAINS SIGNIFICANT ACROSS ABOUT ALL OF
THE WFO CHICAGO CWA...AND HAVE COLLABORATED WITH SPC WHO WILL
SHORTLY BE EXPANDING THE MODERATE RISK FARTHER NORTHEAST INCLUDING
THE CHICAGO METRO AREA.
RATZER
&&
.SHORT TERM...
332 PM CDT
LATE TONIGHT THROUGH TUESDAY...
BULK OF THUNDERSTORM ACTIVITY WILL EXIT DURING THE REMAINING
OVERNIGHT HOURS...HOWEVER...BROAD CYCLONIC FLOW USHERING IN A
STEADY STREAM OF SHORTWAVE ENERGY COULD ALLOW FOR ADDITIONAL
ISOLATED TO SCATTERED DEVELOPMENT THROUGH EARLY TUESDAY MORNING.
COVERAGE WILL LIKELY BE LOW...AND SO HAVE ONLY MAINTAINED SLIGHT
CHANCE TO LOW CHANCE POPS. FRONT WILL PUSH THROUGH THE AREA
THROUGH TUESDAY MORNING...BUT DONT THINK LOW LEVEL MOISTURE WILL
SCOUR TOO MUCH. GUIDANCE IN FAIR AGREEMENT WITH LOWER 70S
DEWPOINTS STILL LINGERING ACROSS THE CWA THROUGH TUESDAY. WITH
MODERATE INSTABILITY REMAINING PRESENT OVER THE CWA AND WITH
ADDITIONAL SURFACE FOCUS OWING TO SOUTHWARD MOVING SURFACE
TROUGH/BOUNDARY...THINK SCATTERED THUNDERSTORM DEVELOPMENT WILL
ONCE AGAIN BE POSSIBLE BY EARLY TUESDAY AFTERNOON. FLOW ALOFT
REMAINS SUFFICIENT FOR MODERATE BULK SHEAR VALUES TO BE IN
PLACE...AND WITH ALL OF THE FEATURES...DO THINK THAT THERE IS AT
LEAST A DECENT POSSIBILITY FOR ADDITIONAL STRONG STORMS DURING
THIS TIME.
RODRIGUEZ
&&
.LONG TERM...
240 PM CDT
TUESDAY NIGHT THROUGH MONDAY...
AN UPPER TROUGH AXIS WILL BE CLEARING THE AREA TUESDAY EVENING
WHILE UPPER RIDGING AMPLIFIES INTO THE NORTHERN PLAINS. SURFACE
HIGH PRESSURE WILL SPREAD SOUTHEASTWARD INTO THE GREAT LAKES. THIS
WILL BRING A COOL DOWN ALONG WITH NORTHEASTERLY LOW LEVEL FLOW. SO
WHILE INLAND AREAS WILL WARM TO THE UPPER 70S TO NEAR 80 LAKESHORE
AREAS WILL BE HELD TO THE LOWER 70S WEDNESDAY. THE SURFACE HIGH
WILL SHIFT EAST WEDNESDAY NIGHT WHILE THE UPPER RIDGE AXIS IS
SHUNTED EASTWARD OVER THE LOCAL AREA BY AN UPPER TROUGH MOVING
ACROSS THE MID/UPPER MISSISSIPPI RIVER VALLEY. THIS WILL RESULT IN
A PUSH OF WARM ADVECTION AND A STEADIER SOUTHERLY LOW LEVEL FLOW
FOR THURSDAY WHICH WILL MEAN WARMER TEMPS. THE BEST FORCING LOOKS
TO BE NORTH OF THE AREA AHEAD OF THE UPPER TROUGH BUT WAA WILL
PROBABLY BE STRONG ENOUGH TO BRING SOME SHOWER AND THUNDERSTORM
ACTIVITY FROM WEST TO EAST ACROSS THE AREA THURSDAY. THE UPPER
FLOW WILL BE DE-AMPLIFYING AS IT PASSES BUT SEVERAL SHORTWAVES
LOOK TO MOVE THROUGH THE FLOW AND A SURFACE LOW IS EXPECTED TO
MOVE NEAR/NORTH OF THE AREA THURSDAY NIGHT. THIS WILL KEEP DECENT
CHANCES FOR SHOWERS AND STORMS IN THE FORECAST. THE LOW WEAKENS AS
IT MOVES NORTHEAST AND ITS ATTENDANT FRONT WASHES OUT TO SOME
EXTENT SO WARMTH WILL CONTINUE TO BUILD ON SOUTHWEST WINDS. SOME
PRECIP COULD LINGER FRIDAY MORNING BUT IT DOES APPEAR DRY
CONDITIONS WILL RETURN FOR AT LEAST A SHORT TIME LATER IN THE DAY
AND FRIDAY NIGHT. ANOTHER UPPER RIDGE AMPLIFIES INTO THE AREA
SATURDAY SO WARM AND HUMID CONDITIONS WILL CONTINUE WITH A PARADE
OF SHORTWAVES BRINGING PERIODIC THUNDERSTORM CHANCES THROUGH THE
WEEKEND. SATURDAY LOOKS TO BE THE WARMEST DAY WHERE SOME AREAS
COULD REACH 90..ESPECIALLY SOUTH AND WEST...BEFORE TEMPS MODERATE
SLIGHTLY SUNDAY.
MDB
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 20Z...
* TIMING...EXTENT...AND DURATION OF CONVECTION THIS AFTERNOON.
LENNING
//DISCUSSION...UPDATED 18Z...
THUNDERSTORMS ARE EXPECTED TO FIRE THIS AFTERNOON ACROSS
SOUTHEAST IOWA INTO CENTRAL ILLINOIS WHERE A BOUNDARY EXISTS
BETWEEN COOL OUTFLOW FROM MORNING STORMS AND THE WARM MOIST AIR
PUSHING UP FROM THE SOUTH. ADDITIONAL DEVELOPMENT EAST OF THIS
AREA WOULD THEN SPREAD INTO THE ORD/MDW TERMINALS TOWARD MID TO
LATE AFTERNOON. ISOLATED SHOWERS ARE POSSIBLE AHEAD OF THIS
ACTIVITY. THE TAF SHOWS A FOUR HOUR TEMPO WINDOW OF GREATEST
LIKELIHOOD BUT THIS ACTIVITY WOULD NOT BE EXPECTED TO PERSIST FOR
THAT LONG.
LENNING
//ORD AND MDW CONFIDENCE...UPDATED 20Z...
* HIGH CONFIDENCE THAT STORMS WILL DEVELOP BUT MEDIUM CONFIDENCE
ON TIMING INTO THE LOCAL TERMINALS. IN LATEST TAF AMENDMENT
PUSHED START TIME BACK AN HOUR...AND WILL CONTINUE MONITORING
NEED FOR ADDITIONAL CHANGES.
LENNING
//OUTLOOK FOR ORD/MDW FOR 00Z WEDNESDAY-12Z MONDAY...UPDATED 12Z...
TUESDAY NIGHT......SLIGHT CHANCE SHRA/TSRA...OTHERWISE VFR.
WEDNESDAY AND THURSDAY...PRIMARILY VFR.
THURSDAY NIGHT AND FRIDAY...SHRA/TSRA POSSIBLE.
SATURDAY...VFR LIKELY.
SUNDAY...SHRA POSSIBLE. VFR LIKELY.
LENNING
&&
.MARINE...
349 PM CDT
SOUTHERLY WINDS OF 10 TO 20 KT CONTINUE ACROSS THE LAKE THIS
AFTERNOON...AS LOW PRESSURE REMAINS JUST TO THE WEST/NORTHWEST.
EXPECT THIS SOUTHERLY FLOW TO PERSIST FOR A PORTION OF THIS
EVENING/TONIGHT UNTIL WINDS SHIFT TO THE NORTH...AS THIS LOW AND
ASSOCIATED FRONTAL BOUNDARY MOVE THROUGH THE REGION. THESE
NORTHERLY WINDS WILL INCREASE ON TUESDAY...WITH NORTH WINDS OF 15
TO 25 KT AND THEN TO 30 KT LIKELY BY THE AFTERNOON AND EARLY
EVENING. WAVES WILL BUILD THROUGH THIS PERIOD AND THINK HAZARDOUS
CONDITIONS FOR SMALL CRAFT WILL OCCUR FOR BOTH THE ILLINOIS AND
INDIANA NEARSHORE WATERS BY EARLY TUESDAY EVENING.
RODRIGUEZ
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...FLASH FLOOD WATCH...ILZ003-ILZ004-ILZ005-ILZ006-ILZ008-ILZ010-
ILZ011-ILZ012-ILZ013-ILZ014-ILZ019-ILZ020-ILZ021-ILZ022-
ILZ023-ILZ032-ILZ033-ILZ039 UNTIL 1 AM TUESDAY.
HEAT ADVISORY...ILZ010-ILZ019-ILZ021-ILZ023-ILZ032-ILZ033-ILZ039
UNTIL 7 PM MONDAY.
IN...FLASH FLOOD WATCH...INZ001-INZ002-INZ010-INZ011-INZ019 UNTIL 1
AM TUESDAY.
LM...NONE.
&&
$$
VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
WWW.FACEBOOK.COM/NWSCHICAGO
WWW.TWITTER.COM/NWSCHICAGO
WWW.YOUTUBE.COM/NWSCHICAGO
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
334 PM CDT MON JUL 13 2015
.MESOSCALE DISCUSSION...
252 PM CDT
MESOSCALE ENVIRONMENT CONTINUES TO BE MONITORED THIS AFTERNOON
FOR EVIDENCE OF CONVECTION INITIATION. CAP NOTED IN DVN 18Z RAOB
SUGGESTS A LITTLE LATER DEVELOPMENT...WHILE WARM FRONT APPEARS TO BE
EVOLVING FARTHER NORTHEAST INTO NORTHERN IL AND SUGGESTS MORE
THE MORE SUBSTANTIAL RISK MAY EXISTS FARTHER NORTH/EAST.
18Z SOUNDINGS FROM ILX AND DVN DEPICT A STRONG LOW-LEVEL CAP
NEAR/NORTH OF THE WARM FRONT (DVN)...AND EXTREME INSTABILITY (MUCAPE
OF 5300 J/KG AT DVN AND 6600 J/KG AT ILX). BOTH SOUNDINGS DEPICT
STRONG DEEP LAYER BULK SHEAR AROUND 50 KTS. THIS DATA CONTINUES TO
INDICATE A STRONG POTENTIAL FOR SEVERE THUNDERSTORMS...WITH EROSION
OF THE CAP AND TIME AND LOCATION OF INITIATION THE MAIN QUESTION.
FORECAST SOUNDINGS FROM RECENT RAP RUNS DO INDICATE WEAKENING OF THE
CAP THROUGH LATE AFTERNOON IN THE 22-00Z TIME FRAME. SATELLITE DATA
INDICATES ONE MID-LEVEL SHORT WAVE APPEARS TO BE MOVING EAST ACROSS
LAKE MICHIGAN/NORTHERN INDIANA AT 19Z...WITH A COUPLE OF ADDITIONAL
RIPPLES NOTED BACK TOWARD SOUTHEAST MINNESOTA. WITH SOME CONSISTENCY
CONVECTION ALLOWING MODELS...SUCH AS THE HRRR...SUGGEST THAT
CONVECTION INITIATION MAY VERY WELL OCCUR ACROSS PARTS OF SOUTHEAST
MINNESOTA/NORTHEAST IOWA/SOUTHWEST WISCONSIN...WHERE OUR
NORTHEASTWARD DEVELOPING WARM FRONT INTERSECTS A SW-NE SYNOPTIC
TROUGH ACROSS EASTERN IOWA. STORM MODE IS STILL ANTICIPATED TO BE
DISCRETE SUPERCELLS OR CLUSTERS...THOUGH THE LOW LEVEL WIND FIELD
HAS BECOME MORE HOMOGENEOUSLY SOUTHWEST WITH THE WARM FRONT/OLD
OUTFLOW LESS DISTINCT THAN EARLIER. THEREFORE THE INITIAL SEVERE
THREAT STILL LOOKS TO BE DAMAGING WINDS...VERY LARGE HAIL...AND
TORRENTIAL RAINFALL. SOMEWHAT WEAKER 0-1 KM SHEAR AND 0-1 KM SRH
APPEAR TO INDICATE A LOWER TORNADO THREAT...THOUGH WILL STILL
CERTAINLY EXIST WHERE A STORM INTERACTS WITH LOCALLY BACKED FLOW
ALONG ANY LINGERING BOUNDARIES. UPSCALE GROWTH INTO A LINEAR/BOWING
MCS IS STILL ANTICIPATED LATER THIS EVENING...PERHAPS CONGEALING
OVER OUR SOUTHEASTERN CWA BEFORE EXITING INTO INDIANA.
WITH THE WARM FRONT EVOLVING FARTHER NORTHEAST...IT DOES APPEAR THAT
THE SEVERE WEATHER THREAT REMAINS SIGNIFICANT ACROSS ABOUT ALL OF
THE WFO CHICAGO CWA...AND HAVE COLLABORATED WITH SPC WHO WILL
SHORTLY BE EXPANDING THE MODERATE RISK FARTHER NORTHEAST INCLUDING
THE CHICAGO METRO AREA.
RATZER
&&
.SHORT TERM...
332 PM CDT
LATE TONIGHT THROUGH TUESDAY...
BULK OF THUNDERSTORM ACTIVITY WILL EXIT DURING THE REMAINING
OVERNIGHT HOURS...HOWEVER...BROAD CYCLONIC FLOW USHERING IN A
STEADY STREAM OF SHORTWAVE ENERGY COULD ALLOW FOR ADDITIONAL
ISOLATED TO SCATTERED DEVELOPMENT THROUGH EARLY TUESDAY MORNING.
COVERAGE WILL LIKELY BE LOW...AND SO HAVE ONLY MAINTAINED SLIGHT
CHANCE TO LOW CHANCE POPS. FRONT WILL PUSH THROUGH THE AREA
THROUGH TUESDAY MORNING...BUT DONT THINK LOW LEVEL MOISTURE WILL
SCOUR TOO MUCH. GUIDANCE IN FAIR AGREEMENT WITH LOWER 70S
DEWPOINTS STILL LINGERING ACROSS THE CWA THROUGH TUESDAY. WITH
MODERATE INSTABILITY REMAINING PRESENT OVER THE CWA AND WITH
ADDITIONAL SURFACE FOCUS OWING TO SOUTHWARD MOVING SURFACE
TROUGH/BOUNDARY...THINK SCATTERED THUNDERSTORM DEVELOPMENT WILL
ONCE AGAIN BE POSSIBLE BY EARLY TUESDAY AFTERNOON. FLOW ALOFT
REMAINS SUFFICIENT FOR MODERATE BULK SHEAR VALUES TO BE IN
PLACE...AND WITH ALL OF THE FEATURES...DO THINK THAT THERE IS AT
LEAST A DECENT POSSIBILITY FOR ADDITIONAL STRONG STORMS DURING
THIS TIME.
RODRIGUEZ
&&
.LONG TERM...
240 PM CDT
TUESDAY NIGHT THROUGH MONDAY...
AN UPPER TROUGH AXIS WILL BE CLEARING THE AREA TUESDAY EVENING
WHILE UPPER RIDGING AMPLIFIES INTO THE NORTHERN PLAINS. SURFACE
HIGH PRESSURE WILL SPREAD SOUTHEASTWARD INTO THE GREAT LAKES. THIS
WILL BRING A COOL DOWN ALONG WITH NORTHEASTERLY LOW LEVEL FLOW. SO
WHILE INLAND AREAS WILL WARM TO THE UPPER 70S TO NEAR 80 LAKESHORE
AREAS WILL BE HELD TO THE LOWER 70S WEDNESDAY. THE SURFACE HIGH
WILL SHIFT EAST WEDNESDAY NIGHT WHILE THE UPPER RIDGE AXIS IS
SHUNTED EASTWARD OVER THE LOCAL AREA BY AN UPPER TROUGH MOVING
ACROSS THE MID/UPPER MISSISSIPPI RIVER VALLEY. THIS WILL RESULT IN
A PUSH OF WARM ADVECTION AND A STEADIER SOUTHERLY LOW LEVEL FLOW
FOR THURSDAY WHICH WILL MEAN WARMER TEMPS. THE BEST FORCING LOOKS
TO BE NORTH OF THE AREA AHEAD OF THE UPPER TROUGH BUT WAA WILL
PROBABLY BE STRONG ENOUGH TO BRING SOME SHOWER AND THUNDERSTORM
ACTIVITY FROM WEST TO EAST ACROSS THE AREA THURSDAY. THE UPPER
FLOW WILL BE DE-AMPLIFYING AS IT PASSES BUT SEVERAL SHORTWAVES
LOOK TO MOVE THROUGH THE FLOW AND A SURFACE LOW IS EXPECTED TO
MOVE NEAR/NORTH OF THE AREA THURSDAY NIGHT. THIS WILL KEEP DECENT
CHANCES FOR SHOWERS AND STORMS IN THE FORECAST. THE LOW WEAKENS AS
IT MOVES NORTHEAST AND ITS ATTENDANT FRONT WASHES OUT TO SOME
EXTENT SO WARMTH WILL CONTINUE TO BUILD ON SOUTHWEST WINDS. SOME
PRECIP COULD LINGER FRIDAY MORNING BUT IT DOES APPEAR DRY
CONDITIONS WILL RETURN FOR AT LEAST A SHORT TIME LATER IN THE DAY
AND FRIDAY NIGHT. ANOTHER UPPER RIDGE AMPLIFIES INTO THE AREA
SATURDAY SO WARM AND HUMID CONDITIONS WILL CONTINUE WITH A PARADE
OF SHORTWAVES BRINGING PERIODIC THUNDERSTORM CHANCES THROUGH THE
WEEKEND. SATURDAY LOOKS TO BE THE WARMEST DAY WHERE SOME AREAS
COULD REACH 90..ESPECIALLY SOUTH AND WEST...BEFORE TEMPS MODERATE
SLIGHTLY SUNDAY.
MDB
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 20Z...
* TIMING...EXTENT...AND DURATION OF CONVECTION THIS AFTERNOON.
LENNING
//DISCUSSION...UPDATED 18Z...
THUNDERSTORMS ARE EXPECTED TO FIRE THIS AFTERNOON ACROSS
SOUTHEAST IOWA INTO CENTRAL ILLINOIS WHERE A BOUNDARY EXISTS
BETWEEN COOL OUTFLOW FROM MORNING STORMS AND THE WARM MOIST AIR
PUSHING UP FROM THE SOUTH. ADDITIONAL DEVELOPMENT EAST OF THIS
AREA WOULD THEN SPREAD INTO THE ORD/MDW TERMINALS TOWARD MID TO
LATE AFTERNOON. ISOLATED SHOWERS ARE POSSIBLE AHEAD OF THIS
ACTIVITY. THE TAF SHOWS A FOUR HOUR TEMPO WINDOW OF GREATEST
LIKELIHOOD BUT THIS ACTIVITY WOULD NOT BE EXPECTED TO PERSIST FOR
THAT LONG.
LENNING
//ORD AND MDW CONFIDENCE...UPDATED 20Z...
* HIGH CONFIDENCE THAT STORMS WILL DEVELOP BUT MEDIUM CONFIDENCE
ON TIMING INTO THE LOCAL TERMINALS. IN LATEST TAF AMENDMENT
PUSHED START TIME BACK AN HOUR...AND WILL CONTINUE MONITORING
NEED FOR ADDITIONAL CHANGES.
LENNING
//OUTLOOK FOR ORD/MDW FOR 00Z WEDNESDAY-12Z MONDAY...UPDATED 12Z...
TUESDAY NIGHT......SLIGHT CHANCE SHRA/TSRA...OTHERWISE VFR.
WEDNESDAY AND THURSDAY...PRIMARILY VFR.
THURSDAY NIGHT AND FRIDAY...SHRA/TSRA POSSIBLE.
SATURDAY...VFR LIKELY.
SUNDAY...SHRA POSSIBLE. VFR LIKELY.
LENNING
&&
.MARINE...
207 AM CDT
WITH LOW PRESSURE APPROACHING FROM THE WEST TODAY...WINDS WILL WANT
TO BE SOUTHERLY ACROSS LAKE MICHIGAN. THE EXCEPTION TO THIS WILL
BE THIS MORNING WHEN A STORM COMPLEX PASSES OVER CENTRAL AND
SOUTHERN PORTIONS OF THE LAKE. THESE STORMS WILL LIKELY
TEMPORARILY SHIFT WINDS WESTERLY AND POSSIBLY WITH BRIEF GUSTS IN
EXCESS OF 35 KNOTS. AS THE LOW PASSES OVER THE CENTRAL PART OF THE
LAKE NEAR MIDNIGHT...WINDS WILL TURN NORTH ACROSS THE NORTHERN
PART OF THE LAKE. DURING THE DAY TUESDAY THESE NORTHERLY WINDS
SHOULD ENVELOP THE LAKE WITH 20-25KT GUSTS PROBABLE. THIS WILL
LEAD TO BUILDING WAVES THROUGH TUESDAY AFTERNOON AND EVENING IN
THE ILLINOIS AND INDIANA NEARSHORES...THOUGH AT THIS TIME SMALL
CRAFT ADVISORY CRITERIA IS NOT FORECAST.
THE ONLY OTHER THING TO NOTE IS THAT THE FOG THREAT OVER THE LAKE
PER WEBCAMS AND OBSERVATIONS APPEARS TO BE LOW...WITH ANY FOG MORE
IN PATCHES AT PRESENT PER SATELLITE DERIVED PRODUCTS. THE WARMING
WATER TEMPERATURES IN JUST THE PAST WEEK AND A HALF HAVE LIKELY
HELPED TO MINIMIZE THAT CONCERN.
MTF
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...FLASH FLOOD WATCH...ILZ003-ILZ004-ILZ005-ILZ006-ILZ008-ILZ010-
ILZ011-ILZ012-ILZ013-ILZ014-ILZ019-ILZ020-ILZ021-ILZ022-
ILZ023-ILZ032-ILZ033-ILZ039 UNTIL 1 AM TUESDAY.
HEAT ADVISORY...ILZ010-ILZ019-ILZ021-ILZ023-ILZ032-ILZ033-ILZ039
UNTIL 7 PM MONDAY.
IN...FLASH FLOOD WATCH...INZ001-INZ002-INZ010-INZ011-INZ019 UNTIL 1
AM TUESDAY.
LM...NONE.
&&
$$
VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
WWW.FACEBOOK.COM/NWSCHICAGO
WWW.TWITTER.COM/NWSCHICAGO
WWW.YOUTUBE.COM/NWSCHICAGO
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
304 PM CDT MON JUL 13 2015
.MESOSCALE DISCUSSION...
252 PM CDT
MESOSCALE ENVIRONMENT CONTINUES TO BE MONITORED THIS AFTERNOON
FOR EVIDENCE OF CONVECTION INITIATION. CAP NOTED IN DVN 18Z RAOB
SUGGESTS A LITTLE LATER DEVELOPMENT...WHILE WARM FRONT APPEARS TO BE
EVOLVING FARTHER NORTHEAST INTO NORTHERN IL AND SUGGESTS MORE
THE MORE SUBSTANTIAL RISK MAY EXISTS FARTHER NORTH/EAST.
18Z SOUNDINGS FROM ILX AND DVN DEPICT A STRONG LOW-LEVEL CAP
NEAR/NORTH OF THE WARM FRONT (DVN)...AND EXTREME INSTABILITY (MUCAPE
OF 5300 J/KG AT DVN AND 6600 J/KG AT ILX). BOTH SOUNDINGS DEPICT
STRONG DEEP LAYER BULK SHEAR AROUND 50 KTS. THIS DATA CONTINUES TO
INDICATE A STRONG POTENTIAL FOR SEVERE THUNDERSTORMS...WITH EROSION
OF THE CAP AND TIME AND LOCATION OF INITIATION THE MAIN QUESTION.
FORECAST SOUNDINGS FROM RECENT RAP RUNS DO INDICATE WEAKENING OF THE
CAP THROUGH LATE AFTERNOON IN THE 22-00Z TIME FRAME. SATELLITE DATA
INDICATES ONE MID-LEVEL SHORT WAVE APPEARS TO BE MOVING EAST ACROSS
LAKE MICHIGAN/NORTHERN INDIANA AT 19Z...WITH A COUPLE OF ADDITIONAL
RIPPLES NOTED BACK TOWARD SOUTHEAST MINNESOTA. WITH SOME CONSISTENCY
CONVECTION ALLOWING MODELS...SUCH AS THE HRRR...SUGGEST THAT
CONVECTION INITIATION MAY VERY WELL OCCUR ACROSS PARTS OF SOUTHEAST
MINNESOTA/NORTHEAST IOWA/SOUTHWEST WISCONSIN...WHERE OUR
NORTHEASTWARD DEVELOPING WARM FRONT INTERSECTS A SW-NE SYNOPTIC
TROUGH ACROSS EASTERN IOWA. STORM MODE IS STILL ANTICIPATED TO BE
DISCRETE SUPERCELLS OR CLUSTERS...THOUGH THE LOW LEVEL WIND FIELD
HAS BECOME MORE HOMOGENEOUSLY SOUTHWEST WITH THE WARM FRONT/OLD
OUTFLOW LESS DISTINCT THAN EARLIER. THEREFORE THE INITIAL SEVERE
THREAT STILL LOOKS TO BE DAMAGING WINDS...VERY LARGE HAIL...AND
TORRENTIAL RAINFALL. SOMEWHAT WEAKER 0-1 KM SHEAR AND 0-1 KM SRH
APPEAR TO INDICATE A LOWER TORNADO THREAT...THOUGH WILL STILL
CERTAINLY EXIST WHERE A STORM INTERACTS WITH LOCALLY BACKED FLOW
ALONG ANY LINGERING BOUNDARIES. UPSCALE GROWTH INTO A LINEAR/BOWING
MCS IS STILL ANTICIPATED LATER THIS EVENING...PERHAPS CONGEALING
OVER OUR SOUTHEASTERN CWA BEFORE EXITING INTO INDIANA.
WITH THE WARM FRONT EVOLVING FARTHER NORTHEAST...IT DOES APPEAR THAT
THE SEVERE WEATHER THREAT REMAINS SIGNIFICANT ACROSS ABOUT ALL OF
THE WFO CHICAGO CWA...AND HAVE COLLABORATED WITH SPC WHO WILL
SHORTLY BE EXPANDING THE MODERATE RISK FARTHER NORTHEAST INCLUDING
THE CHICAGO METRO AREA.
RATZER
&&
.SHORT TERM...
400 AM CDT
THROUGH WEDNESDAY NIGHT...
SEVERE & FLASH FLOOD THREAT TODAY/TONIGHT & HEAT/HUMIDITY TODAY...
EXTREMELY COMPLEX FORECAST THE REST OF TODAY INTO TONIGHT AND ONE
THAT INCLUDES THE POTENTIAL FOR HIGHER END SEVERE WEATHER OF ALL
HAZARDS. ALSO SOME OPPRESSIVE HEAT POSSIBLY IN THE MIX. THE DEVIL
IS IN THE DETAILS...AND MESOSCALE EVOLUTION TODAY WILL IMPACT
MAGNITUDE AND LOCATION OF SEVERE THREAT...AS WELL AS TEMPS AND
HEAT INDEX VALUES ATTAINED. EVEN WITH LOWER CONFIDENCE DUE TO
UNCERTAINTY IN CONVECTIVE EVOLUTION TODAY...WILL BE ISSUING A HEAT
ADVISORY FOR THE SOUTHWEST THIRD OF THE CWA.
THE BIG QUESTION IS WHAT HAPPENS BEYOND THE ONGOING MCS TO OUR
NORTH THAT WILL LIKELY AFFECT ALL IF NOT MOST OF THE CWA THIS
MORNING AND THEN COULD SHIFT SOUTHEAST OF THE CWA BY MID DAY. FOR
ADDITIONAL DETAILS ON MCS AND ASSOCIATED SEVERE/HEAVY RAIN
POTENTIAL...REFER TO MESOSCALE DISCUSSION. FOR HI-RES CONVECTIVE
ALLOWING GUIDANCE THAT ASSISTED IN NEAR TERM PORTION OF
FORECAST...REFERRED TO MORE CONSISTENT 4KM NAM AND ARW/NMM-EAST.
HAVE DISCOUNTED HRRR/RAP AND WILD RUN TO RUN VARIATION EXHIBITED.
CONCEPTUALLY...EXPECTATION FOR MCS AND ASSOCIATED SHORTWAVE/SPEED
MAX TO PROPAGATE SOUTHEAST WOULD PUT US IN A SUBSIDENT REGIME FROM
THE MID-LATE MORNING INTO THE EARLY AFTERNOON. THERE WILL BE
DISRUPTION OF WIND FIELD AND CANNOT RULE OUT A WAKE LOW...AS WELL
AS PERIOD OF ONSHORE FLOW SLOWING TEMPERATURE RISE ALONG
LAKESHORE. IF NO BACKBUILDING OF MCS OCCURS...REMNANT OUTFLOW
BOUNDARIES ARE STILL LIKELY TO BE LEFT BEHIND. BUT TIMING OF WAVE
SHOULD ALLOW FOR CLOUD COVER TO DISSIPATE AND IMPRESSIVE EML
SAMPLED BY 00Z RAOBS TO OUR SOUTH AND WEST WILL BE ABLE TO FULLY
ADVECT EASTWARD. CLEARING/SUBSIDENCE WILL ALSO ALLOW WARM FRONT
CURRENTLY STRETCHING FROM SOUTHERN MN TO WEST CENTRAL IL TO LIFT
NORTHEAST. LAST 2 RUNS OF NAM12 HAVE REDEVELOPED CONVECTION AROUND
MID-DAY OVER CENTRAL CWA AND THEN PROPAGATED IT SOUTHEAST...WHICH
SLOWS RECOVERY PROCESS...BUT HAVE ALSO LARGELY DISCOUNTED THIS
SOLUTION.
ASSUMING WARM FRONT DOES LIFT NORTHEAST AND BRING CWA INTO WARM
SECTOR...OBS WEST OF THE BOUNDARY ON SUNDAY GENERALLY FEATURED
HIGHS IN THE UPPER 80S TO LOWER 90S AND DEWPOINTS IN THE UPPER 70S
TO AROUND 80. EXTREMELY WET SEASON SO FAR IN SOUTHERN CWA AND
EVAPOTRANSPIRATION FROM LARGE/MATURE CORN CROP LEADS ME TO BELIEVE
THAT AT LEAST A FEW SPOTS IN OUR SOUTHWEST CWA WILL REACH THESE 80
DEGREE/NEAR 80 DEWPOINTS THIS AFTERNOON. COUPLED WITH HIGHS NEAR
90...THIS WILL ENABLE HEAT INDEX VALUES TO PEAK IN 105 TO 110
RANGE...AND THUS ISSUED HEAT ADVISORY FROM LEE COUNTY TO IROQUOIS
COUNTY AND WEST. THE REST OF THE CWA SHOULD SEE PEAK HEAT INDEX
VALUES IN THE 95 TO 105 RANGE...WHICH IS STILL QUITE UNCOMFORTABLE
AND NOT SOMETHING COMMONLY EXPERIENCED THIS SUMMER SO FAR.
TEMP/DEWPOINT/CLOUD COVER FORECAST WILL THEN DICTATE WHETHER
INSTABILITY CAN BE MAXIMIZED OVER THE AREA...AND IF IT
DOES...MLCAPE VALUES OF AT LEAST 4000-5000 J/KG ARE POSSIBLE
THANKS TO HIGH DEWPOINTS AND STEEP MIDLEVEL LAPSE RATES. VOLATILE
AIRMASS WILL ALSO BE TOPPED BY NOSE OF UPPER LEVEL JET MAX OF
60-80 KT AND ABOUT 50 KT OF MIDLEVEL FLOW...PROVIDING 45-50 KT OF
NORTHWEST 0-6KM LAYER SHEAR THIS AFTERNOON INTO THIS EVENING. AT
LEAST ISOLATED TSRA CANNOT BE RULED OUT IN POSSIBLE LULL
PERIOD...BUT IF WE DO GET IT...REINITIATION OF TSRA IS EXPECTED TO
OCCUR LATE AFTERNOON INTO EARLY EVENING JUST TO WEST OR NORTHWEST
OF CWA. S0UTH-SOUTHWEST SURFACE WINDS...WESTERLY 850 MB WINDS OF
25-35 KT AND NORTHWEST MIDLEVEL WINDS WILL PROVIDE PLENTY OF
VEERING WITH HEIGHT. LOCATION OF INITIATION IS IN QUESTION...BUT
SUSPECT THAT APPROACHING COLD FRONT TRAILING FROM SURFACE LOW TO
NORTH...ASCENT FROM UPPER WAVE OVER UPPER MIDWEST AND ALSO
ELONGATED VORT MAX INTO WEST CENTRAL IL WILL BE ENOUGH TO BREAK
ANY CAPPING. ORIENTATION OF NORTHWEST SHEAR VECTOR TO INITIATING
BOUNDARY SHOULD RESULT IN AT LEAST INITIAL DISCRETE SUPERCELL
STORM MODE. THIS ALSO ADDS UNCERTAINTY TO POPS AS COVERAGE COULD
VERY WELL BE SCATTERED AND EVEN STAY SCATTERED IF EVOLUTION INTO
MCS/QLCS DOES NOT OCCUR THIS EVENING.
EXTREME INSTABILITY AND MORE THAN SUFFICIENT SHEAR...INCLUDING AT
THE LOW LEVELS...ESPECIALLY NEAR ANY LEFTOVER BOUNDARIES...MEANS
THAT EXPLOSIVE DEVELOPMENT AND ALL SEVERE HAZARDS ARE POSSIBLE.
THIS INCLUDES THE POTENTIAL FOR HIGH END DAMAGING WINDS/ESPECIALLY
IF TRANSITION TO A SEVERE MCS/QLCS OCCURS. IN ADDITION...DISCRETE
DEVELOPMENT REMAINING DOMINANT WOULD FAVOR POTENTIAL FOR
TORNADOES...INCLUDING A STRONG TORNADO OR TWO...AND LARGE TO VERY
LARGE HAIL. STORM MOTION WOULD FAVOR SOUTHEAST MOVEMENT INTO THE
MID TO LATE EVENING. IF SHORT WAVE APPROACHING FROM IA THIS
AFTERNOON ENDS UP BEING FOCUS FOR MORE WIDESPREAD
DEVELOPMENT...THIS COULD KEEP HIGHER END SEVERE THREAT OUT OF FAR
NORTHERN AND NORTHEAST IL AND EXTREME NORTHWEST INDIANA...AS PER
CURRENT DEPICTION OF MODERATE AND ENHANCED RISK FROM CWA. ANY
INTENSE CONVECTION WILL BE IN AN EXTREMELY MOIST AIRMASS...SO
EXCESSIVE RAIN RATES AND FLASH FLOODING WOULD BE LIKELY...AS IT
WONT TAKE MUCH WHETHER OVER INUNDATED SOUTHERN CWA OR URBAN AREAS.
NO CHANGES TO GOING FLASH FLOOD WATCH FOR THIS REASON. THE BOTTOM
LINE TODAY INTO TONIGHT IS STAY WEATHER AWARE...HAVE A WAY TO
RECEIVE WARNINGS...AND ALSO HAVE A SEVERE WEATHER SAFETY PLAN IN
PLACE AHEAD OF TIME SHOULD YOU NEED TO ACT. THERE ARE CERTAINLY
SCENARIOS IN WHICH CONVECTIVE EVOLUTION CAN STILL MODULATE OR EVEN
LESSEN SEVERE THREAT TODAY...BUT GIVEN PATTERN RECOGNITION OF
EXTREME CAPE AND SUFFICIENT SHEAR...SUSPECT AT LEAST PARTS OF CWA
WILL EXPERIENCE SEVERE WEATHER LATER TODAY INTO THIS EVENING AFTER
WHATEVER OCCURS THIS MORNING.
TUESDAY THROUGH WEDNESDAY NIGHT...
TUESDAY COULD FEATURE AT LEAST SCATTERED TSRA DEVELOPMENT AS
SECONDARY COLD FRONT/TROUGH AXIS INTERACTS WITH A STILL WARM AND
MOIST AIR MASS. COOLER AND DRIER AIR LOOKS TO MAKE A BRIEF RETURN
ON WEDNESDAY.
RC
&&
.LONG TERM...
240 PM CDT
TUESDAY NIGHT THROUGH MONDAY...
AN UPPER TROUGH AXIS WILL BE CLEARING THE AREA TUESDAY EVENING
WHILE UPPER RIDGING AMPLIFIES INTO THE NORTHERN PLAINS. SURFACE
HIGH PRESSURE WILL SPREAD SOUTHEASTWARD INTO THE GREAT LAKES. THIS
WILL BRING A COOL DOWN ALONG WITH NORTHEASTERLY LOW LEVEL FLOW. SO
WHILE INLAND AREAS WILL WARM TO THE UPPER 70S TO NEAR 80 LAKESHORE
AREAS WILL BE HELD TO THE LOWER 70S WEDNESDAY. THE SURFACE HIGH
WILL SHIFT EAST WEDNESDAY NIGHT WHILE THE UPPER RIDGE AXIS IS
SHUNTED EASTWARD OVER THE LOCAL AREA BY AN UPPER TROUGH MOVING
ACROSS THE MID/UPPER MISSISSIPPI RIVER VALLEY. THIS WILL RESULT IN
A PUSH OF WARM ADVECTION AND A STEADIER SOUTHERLY LOW LEVEL FLOW
FOR THURSDAY WHICH WILL MEAN WARMER TEMPS. THE BEST FORCING LOOKS
TO BE NORTH OF THE AREA AHEAD OF THE UPPER TROUGH BUT WAA WILL
PROBABLY BE STRONG ENOUGH TO BRING SOME SHOWER AND THUNDERSTORM
ACTIVITY FROM WEST TO EAST ACROSS THE AREA THURSDAY. THE UPPER
FLOW WILL BE DE-AMPLIFYING AS IT PASSES BUT SEVERAL SHORTWAVES
LOOK TO MOVE THROUGH THE FLOW AND A SURFACE LOW IS EXPECTED TO
MOVE NEAR/NORTH OF THE AREA THURSDAY NIGHT. THIS WILL KEEP DECENT
CHANCES FOR SHOWERS AND STORMS IN THE FORECAST. THE LOW WEAKENS AS
IT MOVES NORTHEAST AND ITS ATTENDANT FRONT WASHES OUT TO SOME
EXTENT SO WARMTH WILL CONTINUE TO BUILD ON SOUTHWEST WINDS. SOME
PRECIP COULD LINGER FRIDAY MORNING BUT IT DOES APPEAR DRY
CONDITIONS WILL RETURN FOR AT LEAST A SHORT TIME LATER IN THE DAY
AND FRIDAY NIGHT. ANOTHER UPPER RIDGE AMPLIFIES INTO THE AREA
SATURDAY SO WARM AND HUMID CONDITIONS WILL CONTINUE WITH A PARADE
OF SHORTWAVES BRINGING PERIODIC THUNDERSTORM CHANCES THROUGH THE
WEEKEND. SATURDAY LOOKS TO BE THE WARMEST DAY WHERE SOME AREAS
COULD REACH 90..ESPECIALLY SOUTH AND WEST...BEFORE TEMPS MODERATE
SLIGHTLY SUNDAY.
MDB
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 20Z...
* TIMING...EXTENT...AND DURATION OF CONVECTION THIS AFTERNOON.
LENNING
//DISCUSSION...UPDATED 18Z...
THUNDERSTORMS ARE EXPECTED TO FIRE THIS AFTERNOON ACROSS
SOUTHEAST IOWA INTO CENTRAL ILLINOIS WHERE A BOUNDARY EXISTS
BETWEEN COOL OUTFLOW FROM MORNING STORMS AND THE WARM MOIST AIR
PUSHING UP FROM THE SOUTH. ADDITIONAL DEVELOPMENT EAST OF THIS
AREA WOULD THEN SPREAD INTO THE ORD/MDW TERMINALS TOWARD MID TO
LATE AFTERNOON. ISOLATED SHOWERS ARE POSSIBLE AHEAD OF THIS
ACTIVITY. THE TAF SHOWS A FOUR HOUR TEMPO WINDOW OF GREATEST
LIKELIHOOD BUT THIS ACTIVITY WOULD NOT BE EXPECTED TO PERSIST FOR
THAT LONG.
LENNING
//ORD AND MDW CONFIDENCE...UPDATED 20Z...
* HIGH CONFIDENCE THAT STORMS WILL DEVELOP BUT MEDIUM CONFIDENCE
ON TIMING INTO THE LOCAL TERMINALS. IN LATEST TAF AMENDMENT
PUSHED START TIME BACK AN HOUR...AND WILL CONTINUE MONITORING
NEED FOR ADDITIONAL CHANGES.
LENNING
//OUTLOOK FOR ORD/MDW FOR 00Z WEDNESDAY-12Z MONDAY...UPDATED 12Z...
TUESDAY NIGHT......SLIGHT CHANCE SHRA/TSRA...OTHERWISE VFR.
WEDNESDAY AND THURSDAY...PRIMARILY VFR.
THURSDAY NIGHT AND FRIDAY...SHRA/TSRA POSSIBLE.
SATURDAY...VFR LIKELY.
SUNDAY...SHRA POSSIBLE. VFR LIKELY.
LENNING
&&
.MARINE...
207 AM CDT
WITH LOW PRESSURE APPROACHING FROM THE WEST TODAY...WINDS WILL WANT
TO BE SOUTHERLY ACROSS LAKE MICHIGAN. THE EXCEPTION TO THIS WILL
BE THIS MORNING WHEN A STORM COMPLEX PASSES OVER CENTRAL AND
SOUTHERN PORTIONS OF THE LAKE. THESE STORMS WILL LIKELY
TEMPORARILY SHIFT WINDS WESTERLY AND POSSIBLY WITH BRIEF GUSTS IN
EXCESS OF 35 KNOTS. AS THE LOW PASSES OVER THE CENTRAL PART OF THE
LAKE NEAR MIDNIGHT...WINDS WILL TURN NORTH ACROSS THE NORTHERN
PART OF THE LAKE. DURING THE DAY TUESDAY THESE NORTHERLY WINDS
SHOULD ENVELOP THE LAKE WITH 20-25KT GUSTS PROBABLE. THIS WILL
LEAD TO BUILDING WAVES THROUGH TUESDAY AFTERNOON AND EVENING IN
THE ILLINOIS AND INDIANA NEARSHORES...THOUGH AT THIS TIME SMALL
CRAFT ADVISORY CRITERIA IS NOT FORECAST.
THE ONLY OTHER THING TO NOTE IS THAT THE FOG THREAT OVER THE LAKE
PER WEBCAMS AND OBSERVATIONS APPEARS TO BE LOW...WITH ANY FOG MORE
IN PATCHES AT PRESENT PER SATELLITE DERIVED PRODUCTS. THE WARMING
WATER TEMPERATURES IN JUST THE PAST WEEK AND A HALF HAVE LIKELY
HELPED TO MINIMIZE THAT CONCERN.
MTF
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...FLASH FLOOD WATCH...ILZ003-ILZ004-ILZ005-ILZ006-ILZ008-ILZ010-
ILZ011-ILZ012-ILZ013-ILZ014-ILZ019-ILZ020-ILZ021-ILZ022-
ILZ023-ILZ032-ILZ033-ILZ039 UNTIL 1 AM TUESDAY.
HEAT ADVISORY...ILZ010-ILZ019-ILZ021-ILZ023-ILZ032-ILZ033-ILZ039
UNTIL 7 PM MONDAY.
IN...FLASH FLOOD WATCH...INZ001-INZ002-INZ010-INZ011-INZ019 UNTIL 1
AM TUESDAY.
LM...NONE.
&&
$$
VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
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WWW.YOUTUBE.COM/NWSCHICAGO
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
252 PM CDT MON JUL 13 2015
.MESOSCALE DISCUSSION...
252 PM CDT
MESOSCALE ENVIRONMENT CONTINUES TO BE MONITORED THIS AFTERNOON
FOR EVIDENCE OF CONVECTION INITIATION. CAP NOTED IN DVN 18Z RAOB
SUGGESTS A LITTLE LATER DEVELOPMENT...WHILE WARM FRONT APPEARS TO BE
EVOLVING FARTHER NORTHEAST INTO NORTHERN IL AND SUGGESTS MORE
THE MORE SUBSTANTIAL RISK MAY EXISTS FARTHER NORTH/EAST.
18Z SOUNDINGS FROM ILX AND DVN DEPICT A STRONG LOW-LEVEL CAP
NEAR/NORTH OF THE WARM FRONT (DVN)...AND EXTREME INSTABILITY (MUCAPE
OF 5300 J/KG AT DVN AND 6600 J/KG AT ILX). BOTH SOUNDINGS DEPICT
STRONG DEEP LAYER BULK SHEAR AROUND 50 KTS. THIS DATA CONTINUES TO
INDICATE A STRONG POTENTIAL FOR SEVERE THUNDERSTORMS...WITH EROSION
OF THE CAP AND TIME AND LOCATION OF INITIATION THE MAIN QUESTION.
FORECAST SOUNDINGS FROM RECENT RAP RUNS DO INDICATE WEAKENING OF THE
CAP THROUGH LATE AFTERNOON IN THE 22-00Z TIME FRAME. SATELLITE DATA
INDICATES ONE MID-LEVEL SHORT WAVE APPEARS TO BE MOVING EAST ACROSS
LAKE MICHIGAN/NORTHERN INDIANA AT 19Z...WITH A COUPLE OF ADDITIONAL
RIPPLES NOTED BACK TOWARD SOUTHEAST MINNESOTA. WITH SOME CONSISTENCY
CONVECTION ALLOWING MODELS...SUCH AS THE HRRR...SUGGEST THAT
CONVECTION INITIATION MAY VERY WELL OCCUR ACROSS PARTS OF SOUTHEAST
MINNESOTA/NORTHEAST IOWA/SOUTHWEST WISCONSIN...WHERE OUR
NORTHEASTWARD DEVELOPING WARM FRONT INTERSECTS A SW-NE SYNOPTIC
TROUGH ACROSS EASTERN IOWA. STORM MODE IS STILL ANTICIPATED TO BE
DISCRETE SUPERCELLS OR CLUSTERS...THOUGH THE LOW LEVEL WIND FIELD
HAS BECOME MORE HOMOGENEOUSLY SOUTHWEST WITH THE WARM FRONT/OLD
OUTFLOW LESS DISTINCT THAN EARLIER. THEREFORE THE INITIAL SEVERE
THREAT STILL LOOKS TO BE DAMAGING WINDS...VERY LARGE HAIL...AND
TORRENTIAL RAINFALL. SOMEWHAT WEAKER 0-1 KM SHEAR AND 0-1 KM SRH
APPEAR TO INDICATE A LOWER TORNADO THREAT...THOUGH WILL STILL
CERTAINLY EXIST WHERE A STORM INTERACTS WITH LOCALLY BACKED FLOW
ALONG ANY LINGERING BOUNDARIES. UPSCALE GROWTH INTO A LINEAR/BOWING
MCS IS STILL ANTICIPATED LATER THIS EVENING...PERHAPS CONGEALING
OVER OUR SOUTHEASTERN CWA BEFORE EXITING INTO INDIANA.
WITH THE WARM FRONT EVOLVING FARTHER NORTHEAST...IT DOES APPEAR THAT
THE SEVERE WEATHER THREAT REMAINS SIGNIFICANT ACROSS ABOUT ALL OF
THE WFO CHICAGO CWA...AND HAVE COLLABORATED WITH SPC WHO WILL
SHORTLY BE EXPANDING THE MODERATE RISK FARTHER NORTHEAST INCLUDING
THE CHICAGO METRO AREA.
RATZER
&&
.SHORT TERM...
400 AM CDT
THROUGH WEDNESDAY NIGHT...
SEVERE & FLASH FLOOD THREAT TODAY/TONIGHT & HEAT/HUMIDITY TODAY...
EXTREMELY COMPLEX FORECAST THE REST OF TODAY INTO TONIGHT AND ONE
THAT INCLUDES THE POTENTIAL FOR HIGHER END SEVERE WEATHER OF ALL
HAZARDS. ALSO SOME OPPRESSIVE HEAT POSSIBLY IN THE MIX. THE DEVIL
IS IN THE DETAILS...AND MESOSCALE EVOLUTION TODAY WILL IMPACT
MAGNITUDE AND LOCATION OF SEVERE THREAT...AS WELL AS TEMPS AND
HEAT INDEX VALUES ATTAINED. EVEN WITH LOWER CONFIDENCE DUE TO
UNCERTAINTY IN CONVECTIVE EVOLUTION TODAY...WILL BE ISSUING A HEAT
ADVISORY FOR THE SOUTHWEST THIRD OF THE CWA.
THE BIG QUESTION IS WHAT HAPPENS BEYOND THE ONGOING MCS TO OUR
NORTH THAT WILL LIKELY AFFECT ALL IF NOT MOST OF THE CWA THIS
MORNING AND THEN COULD SHIFT SOUTHEAST OF THE CWA BY MID DAY. FOR
ADDITIONAL DETAILS ON MCS AND ASSOCIATED SEVERE/HEAVY RAIN
POTENTIAL...REFER TO MESOSCALE DISCUSSION. FOR HI-RES CONVECTIVE
ALLOWING GUIDANCE THAT ASSISTED IN NEAR TERM PORTION OF
FORECAST...REFERRED TO MORE CONSISTENT 4KM NAM AND ARW/NMM-EAST.
HAVE DISCOUNTED HRRR/RAP AND WILD RUN TO RUN VARIATION EXHIBITED.
CONCEPTUALLY...EXPECTATION FOR MCS AND ASSOCIATED SHORTWAVE/SPEED
MAX TO PROPAGATE SOUTHEAST WOULD PUT US IN A SUBSIDENT REGIME FROM
THE MID-LATE MORNING INTO THE EARLY AFTERNOON. THERE WILL BE
DISRUPTION OF WIND FIELD AND CANNOT RULE OUT A WAKE LOW...AS WELL
AS PERIOD OF ONSHORE FLOW SLOWING TEMPERATURE RISE ALONG
LAKESHORE. IF NO BACKBUILDING OF MCS OCCURS...REMNANT OUTFLOW
BOUNDARIES ARE STILL LIKELY TO BE LEFT BEHIND. BUT TIMING OF WAVE
SHOULD ALLOW FOR CLOUD COVER TO DISSIPATE AND IMPRESSIVE EML
SAMPLED BY 00Z RAOBS TO OUR SOUTH AND WEST WILL BE ABLE TO FULLY
ADVECT EASTWARD. CLEARING/SUBSIDENCE WILL ALSO ALLOW WARM FRONT
CURRENTLY STRETCHING FROM SOUTHERN MN TO WEST CENTRAL IL TO LIFT
NORTHEAST. LAST 2 RUNS OF NAM12 HAVE REDEVELOPED CONVECTION AROUND
MID-DAY OVER CENTRAL CWA AND THEN PROPAGATED IT SOUTHEAST...WHICH
SLOWS RECOVERY PROCESS...BUT HAVE ALSO LARGELY DISCOUNTED THIS
SOLUTION.
ASSUMING WARM FRONT DOES LIFT NORTHEAST AND BRING CWA INTO WARM
SECTOR...OBS WEST OF THE BOUNDARY ON SUNDAY GENERALLY FEATURED
HIGHS IN THE UPPER 80S TO LOWER 90S AND DEWPOINTS IN THE UPPER 70S
TO AROUND 80. EXTREMELY WET SEASON SO FAR IN SOUTHERN CWA AND
EVAPOTRANSPIRATION FROM LARGE/MATURE CORN CROP LEADS ME TO BELIEVE
THAT AT LEAST A FEW SPOTS IN OUR SOUTHWEST CWA WILL REACH THESE 80
DEGREE/NEAR 80 DEWPOINTS THIS AFTERNOON. COUPLED WITH HIGHS NEAR
90...THIS WILL ENABLE HEAT INDEX VALUES TO PEAK IN 105 TO 110
RANGE...AND THUS ISSUED HEAT ADVISORY FROM LEE COUNTY TO IROQUOIS
COUNTY AND WEST. THE REST OF THE CWA SHOULD SEE PEAK HEAT INDEX
VALUES IN THE 95 TO 105 RANGE...WHICH IS STILL QUITE UNCOMFORTABLE
AND NOT SOMETHING COMMONLY EXPERIENCED THIS SUMMER SO FAR.
TEMP/DEWPOINT/CLOUD COVER FORECAST WILL THEN DICTATE WHETHER
INSTABILITY CAN BE MAXIMIZED OVER THE AREA...AND IF IT
DOES...MLCAPE VALUES OF AT LEAST 4000-5000 J/KG ARE POSSIBLE
THANKS TO HIGH DEWPOINTS AND STEEP MIDLEVEL LAPSE RATES. VOLATILE
AIRMASS WILL ALSO BE TOPPED BY NOSE OF UPPER LEVEL JET MAX OF
60-80 KT AND ABOUT 50 KT OF MIDLEVEL FLOW...PROVIDING 45-50 KT OF
NORTHWEST 0-6KM LAYER SHEAR THIS AFTERNOON INTO THIS EVENING. AT
LEAST ISOLATED TSRA CANNOT BE RULED OUT IN POSSIBLE LULL
PERIOD...BUT IF WE DO GET IT...REINITIATION OF TSRA IS EXPECTED TO
OCCUR LATE AFTERNOON INTO EARLY EVENING JUST TO WEST OR NORTHWEST
OF CWA. S0UTH-SOUTHWEST SURFACE WINDS...WESTERLY 850 MB WINDS OF
25-35 KT AND NORTHWEST MIDLEVEL WINDS WILL PROVIDE PLENTY OF
VEERING WITH HEIGHT. LOCATION OF INITIATION IS IN QUESTION...BUT
SUSPECT THAT APPROACHING COLD FRONT TRAILING FROM SURFACE LOW TO
NORTH...ASCENT FROM UPPER WAVE OVER UPPER MIDWEST AND ALSO
ELONGATED VORT MAX INTO WEST CENTRAL IL WILL BE ENOUGH TO BREAK
ANY CAPPING. ORIENTATION OF NORTHWEST SHEAR VECTOR TO INITIATING
BOUNDARY SHOULD RESULT IN AT LEAST INITIAL DISCRETE SUPERCELL
STORM MODE. THIS ALSO ADDS UNCERTAINTY TO POPS AS COVERAGE COULD
VERY WELL BE SCATTERED AND EVEN STAY SCATTERED IF EVOLUTION INTO
MCS/QLCS DOES NOT OCCUR THIS EVENING.
EXTREME INSTABILITY AND MORE THAN SUFFICIENT SHEAR...INCLUDING AT
THE LOW LEVELS...ESPECIALLY NEAR ANY LEFTOVER BOUNDARIES...MEANS
THAT EXPLOSIVE DEVELOPMENT AND ALL SEVERE HAZARDS ARE POSSIBLE.
THIS INCLUDES THE POTENTIAL FOR HIGH END DAMAGING WINDS/ESPECIALLY
IF TRANSITION TO A SEVERE MCS/QLCS OCCURS. IN ADDITION...DISCRETE
DEVELOPMENT REMAINING DOMINANT WOULD FAVOR POTENTIAL FOR
TORNADOES...INCLUDING A STRONG TORNADO OR TWO...AND LARGE TO VERY
LARGE HAIL. STORM MOTION WOULD FAVOR SOUTHEAST MOVEMENT INTO THE
MID TO LATE EVENING. IF SHORT WAVE APPROACHING FROM IA THIS
AFTERNOON ENDS UP BEING FOCUS FOR MORE WIDESPREAD
DEVELOPMENT...THIS COULD KEEP HIGHER END SEVERE THREAT OUT OF FAR
NORTHERN AND NORTHEAST IL AND EXTREME NORTHWEST INDIANA...AS PER
CURRENT DEPICTION OF MODERATE AND ENHANCED RISK FROM CWA. ANY
INTENSE CONVECTION WILL BE IN AN EXTREMELY MOIST AIRMASS...SO
EXCESSIVE RAIN RATES AND FLASH FLOODING WOULD BE LIKELY...AS IT
WONT TAKE MUCH WHETHER OVER INUNDATED SOUTHERN CWA OR URBAN AREAS.
NO CHANGES TO GOING FLASH FLOOD WATCH FOR THIS REASON. THE BOTTOM
LINE TODAY INTO TONIGHT IS STAY WEATHER AWARE...HAVE A WAY TO
RECEIVE WARNINGS...AND ALSO HAVE A SEVERE WEATHER SAFETY PLAN IN
PLACE AHEAD OF TIME SHOULD YOU NEED TO ACT. THERE ARE CERTAINLY
SCENARIOS IN WHICH CONVECTIVE EVOLUTION CAN STILL MODULATE OR EVEN
LESSEN SEVERE THREAT TODAY...BUT GIVEN PATTERN RECOGNITION OF
EXTREME CAPE AND SUFFICIENT SHEAR...SUSPECT AT LEAST PARTS OF CWA
WILL EXPERIENCE SEVERE WEATHER LATER TODAY INTO THIS EVENING AFTER
WHATEVER OCCURS THIS MORNING.
TUESDAY THROUGH WEDNESDAY NIGHT...
TUESDAY COULD FEATURE AT LEAST SCATTERED TSRA DEVELOPMENT AS
SECONDARY COLD FRONT/TROUGH AXIS INTERACTS WITH A STILL WARM AND
MOIST AIR MASS. COOLER AND DRIER AIR LOOKS TO MAKE A BRIEF RETURN
ON WEDNESDAY.
RC
&&
.LONG TERM...
240 PM CDT
TUESDAY NIGHT THROUGH MONDAY...
AN UPPER TROUGH AXIS WILL BE CLEARING THE AREA TUESDAY EVENING
WHILE UPPER RIDGING AMPLIFIES INTO THE NORTHERN PLAINS. SURFACE
HIGH PRESSURE WILL SPREAD SOUTHEASTWARD INTO THE GREAT LAKES. THIS
WILL BRING A COOL DOWN ALONG WITH NORTHEASTERLY LOW LEVEL FLOW. SO
WHILE INLAND AREAS WILL WARM TO THE UPPER 70S TO NEAR 80 LAKESHORE
AREAS WILL BE HELD TO THE LOWER 70S WEDNESDAY. THE SURFACE HIGH
WILL SHIFT EAST WEDNESDAY NIGHT WHILE THE UPPER RIDGE AXIS IS
SHUNTED EASTWARD OVER THE LOCAL AREA BY AN UPPER TROUGH MOVING
ACROSS THE MID/UPPER MISSISSIPPI RIVER VALLEY. THIS WILL RESULT IN
A PUSH OF WARM ADVECTION AND A STEADIER SOUTHERLY LOW LEVEL FLOW
FOR THURSDAY WHICH WILL MEAN WARMER TEMPS. THE BEST FORCING LOOKS
TO BE NORTH OF THE AREA AHEAD OF THE UPPER TROUGH BUT WAA WILL
PROBABLY BE STRONG ENOUGH TO BRING SOME SHOWER AND THUNDERSTORM
ACTIVITY FROM WEST TO EAST ACROSS THE AREA THURSDAY. THE UPPER
FLOW WILL BE DE-AMPLIFYING AS IT PASSES BUT SEVERAL SHORTWAVES
LOOK TO MOVE THROUGH THE FLOW AND A SURFACE LOW IS EXPECTED TO
MOVE NEAR/NORTH OF THE AREA THURSDAY NIGHT. THIS WILL KEEP DECENT
CHANCES FOR SHOWERS AND STORMS IN THE FORECAST. THE LOW WEAKENS AS
IT MOVES NORTHEAST AND ITS ATTENDANT FRONT WASHES OUT TO SOME
EXTENT SO WARMTH WILL CONTINUE TO BUILD ON SOUTHWEST WINDS. SOME
PRECIP COULD LINGER FRIDAY MORNING BUT IT DOES APPEAR DRY
CONDITIONS WILL RETURN FOR AT LEAST A SHORT TIME LATER IN THE DAY
AND FRIDAY NIGHT. ANOTHER UPPER RIDGE AMPLIFIES INTO THE AREA
SATURDAY SO WARM AND HUMID CONDITIONS WILL CONTINUE WITH A PARADE
OF SHORTWAVES BRINGING PERIODIC THUNDERSTORM CHANCES THROUGH THE
WEEKEND. SATURDAY LOOKS TO BE THE WARMEST DAY WHERE SOME AREAS
COULD REACH 90..ESPECIALLY SOUTH AND WEST...BEFORE TEMPS MODERATE
SLIGHTLY SUNDAY.
MDB
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 18Z...
* TIMING AND EXTENT OF THUNDERSTORMS THIS AFTERNOON AND EVENING.
* WIND TRENDS IN AND AROUND CONVECTION.
LENNING
//DISCUSSION...UPDATED 18Z...
THUNDERSTORMS ARE EXPECTED TO FIRE THIS AFTERNOON ACROSS
SOUTHEAST IOWA INTO CENTRAL ILLINOIS WHERE A BOUNDARY EXISTS
BETWEEN COOL OUTFLOW FROM MORNING STORMS AND THE WARM MOIST AIR
PUSHING UP FROM THE SOUTH. ADDITIONAL DEVELOPMENT EAST OF THIS
AREA WOULD THEN SPREAD INTO THE ORD/MDW TERMINALS TOWARD MID TO
LATE AFTERNOON. ISOLATED SHOWERS ARE POSSIBLE AHEAD OF THIS
ACTIVITY. THE TAF SHOWS A FOUR HOUR TEMPO WINDOW OF GREATEST
LIKELIHOOD BUT THIS ACTIVITY WOULD NOT BE EXPECTED TO PERSIST FOR
THAT LONG.
LENNING
//ORD AND MDW CONFIDENCE...UPDATED 18Z...
* MEDIUM CONFIDENCE ON TSRA TRENDS TODAY. HIGHER CONFIDENCE IN
WIND TRENDS.
LENNING
//OUTLOOK FOR ORD/MDW FOR 00Z WEDNESDAY-12Z MONDAY...UPDATED 12Z...
TUESDAY NIGHT......SLIGHT CHANCE SHRA/TSRA...OTHERWISE VFR.
WEDNESDAY AND THURSDAY...PRIMARILY VFR.
THURSDAY NIGHT AND FRIDAY...SHRA/TSRA POSSIBLE.
SATURDAY...VFR LIKELY.
SUNDAY...SHRA POSSIBLE. VFR LIKELY.
LENNING
&&
.MARINE...
207 AM CDT
WITH LOW PRESSURE APPROACHING FROM THE WEST TODAY...WINDS WILL WANT
TO BE SOUTHERLY ACROSS LAKE MICHIGAN. THE EXCEPTION TO THIS WILL
BE THIS MORNING WHEN A STORM COMPLEX PASSES OVER CENTRAL AND
SOUTHERN PORTIONS OF THE LAKE. THESE STORMS WILL LIKELY
TEMPORARILY SHIFT WINDS WESTERLY AND POSSIBLY WITH BRIEF GUSTS IN
EXCESS OF 35 KNOTS. AS THE LOW PASSES OVER THE CENTRAL PART OF THE
LAKE NEAR MIDNIGHT...WINDS WILL TURN NORTH ACROSS THE NORTHERN
PART OF THE LAKE. DURING THE DAY TUESDAY THESE NORTHERLY WINDS
SHOULD ENVELOP THE LAKE WITH 20-25KT GUSTS PROBABLE. THIS WILL
LEAD TO BUILDING WAVES THROUGH TUESDAY AFTERNOON AND EVENING IN
THE ILLINOIS AND INDIANA NEARSHORES...THOUGH AT THIS TIME SMALL
CRAFT ADVISORY CRITERIA IS NOT FORECAST.
THE ONLY OTHER THING TO NOTE IS THAT THE FOG THREAT OVER THE LAKE
PER WEBCAMS AND OBSERVATIONS APPEARS TO BE LOW...WITH ANY FOG MORE
IN PATCHES AT PRESENT PER SATELLITE DERIVED PRODUCTS. THE WARMING
WATER TEMPERATURES IN JUST THE PAST WEEK AND A HALF HAVE LIKELY
HELPED TO MINIMIZE THAT CONCERN.
MTF
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...FLASH FLOOD WATCH...ILZ003-ILZ004-ILZ005-ILZ006-ILZ008-ILZ010-
ILZ011-ILZ012-ILZ013-ILZ014-ILZ019-ILZ020-ILZ021-ILZ022-
ILZ023-ILZ032-ILZ033-ILZ039 UNTIL 1 AM TUESDAY.
HEAT ADVISORY...ILZ010-ILZ019-ILZ021-ILZ023-ILZ032-ILZ033-ILZ039
UNTIL 7 PM MONDAY.
IN...FLASH FLOOD WATCH...INZ001-INZ002-INZ010-INZ011-INZ019 UNTIL 1
AM TUESDAY.
LM...NONE.
&&
$$
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AREA FORECAST DISCUSSION
NWS NORTHERN INDIANA
353 PM EDT MON JUL 13 2015
.SYNOPSIS...
ISSUED AT 349 PM EDT MON JUL 13 2015
SEVERE STORMS ARE EXPECTED TO DEVELOP EARLY THIS EVENING AND
CONTINUE THROUGH LATE TONIGHT. THE GREATEST THREAT WILL BE ALONG
AND SOUTH OF U.S. 30 IN INDIANA...BUT SEVERE WEATHER IS POSSIBLE
ACROSS THE ENTIRE FORECAST AREA. DAMAGING WINDS...LARGE
HAIL...AND HEAVY RAIN ARE ALL EXPECTED. BE PREPARED TO TAKE ACTION
IF A WARNING IS ISSUED FOR YOUR AREA.
&&
.SHORT TERM...(THIS EVENING THROUGH TUESDAY)
ISSUED AT 316 PM EDT MON JUL 13 2015
RAPID DESTABILIZATION HAS BEGUN ACROSS NORTHERN ILLINOIS AS EXPECTED
AT 18Z THIS AFTERNOON. THIS DESTABILIZATION WILL CONTINUE TO ADVECT
EASTWARD THROUGH THE AFTERNOON WITH THE WESTERN HALF OF OUR FORECAST
AREA INTO THE WARM SECTOR BY EARLY EVENING. 18Z DVN SPECIAL SOUNDING
SAMPLED NEARLY DRY ADIABATIC LAPSE RATES FROM H850 TO H500 AND
NEARLY 100 KNOTS OF FLOW ABOVE 300MB. WITH SURFACE TEMPERATURES IN
THE MID 80S AND DEWPOINTS IN THE UPPER 70S BENEATH THIS EML...EXPECT
EXTREME INSTABILITY OF 4000 TO 6000 J/KG BY 22Z. THIS INSTABILITY
COUPLED WITH DEEP LAYER SHEAR OF 55 TO 65 KNOTS WILL LEAD TO
EXPLOSIVE STORM DEVELOPMENT AND ORGANIZATION LATER THIS EVENING. HP
SUPERCELLS WILL BE THE PRIMARY STORM MODE FOR THE FIRST FEW HOURS
BEFORE STORMS CONGEAL INTO A FORWARD PROPAGATING MCS.
DURING THIS 22Z TO 02Z TIMEFRAME...SURFACE WINDS WILL REMAIN OUT OF
THE SSW WITH A STRENGTHENING WESTERLY LOW LEVEL JET. EXTREMELY LOW
LCLS COUPLED WITH THIS STRONG LOW LEVEL SHEAR WILL LEAD TO AN
ENHANCED TORNADIC RISK DURING THIS TIMEFRAME. ADDITIONALLY...A
STRONG TORNADO CANNOT BE RULED OUT...ESPECIALLY IF STRONGER 850 FLOW
(35 TO 40 KNOTS) FROM THE LATEST HRRR VERIFIES.
EACH RUN OF THE HRRR HAS ADVECTED THE WARM FRONT PROGRESSIVELY
FURTHER EAST...SO CANNOT RULE OUT A GREATER THREAT FURTHER NORTHEAST
THAN THE CURRENT AREA OF FOCUS WHICH IS ALONG AND SOUTH OF US 30 IN
INDIANA.
MOST OF THE CWA RECEIVED BETWEEN 1 AND 1.5 INCHES WITH THE ROUND OF
RAIN THIS MORNING. FLASH FLOODING APPEARS INCREASINGLY LIKELY THIS
EVENING WITH A VERY HIGH THETA E AIRMASS AND TRAINING STORMS
POSSIBLE. THEREFORE...WILL KEEP THE FLASH FLOOD WATCH IN EFFECT
THROUGH 06Z.
ONCE THESE STORMS MOVE THROUGH...ADDITIONAL STORMS ARE POSSIBLE LATE
TONIGHT AND INTO THE DAY TOMORROW AS THE FRONT DROPS SOUTH THROUGH
OUR AREA. EXPECT THE FRONT TO MOVE SOUTH OF OUR FORECAST AREA BEFORE
ENOUGH INSTABILITY DEVELOPS FOR SEVERE WEATHER WITHIN OUR CWA.
&&
.LONG TERM...(TUESDAY NIGHT THROUGH MONDAY)
ISSUED AT 316 PM EDT MON JUL 13 2015
ROBUST NRN STREAM DISTURBANCE OVR NRN MN WILL DIG SEWD
INTO THE ERN LAKES ON TUE. RESULTING TROUGH AMPLIFICATION ACRS THE
LAKES WILL SHUNT UNSTABLE LL THETA-E RIDGE SWWD UNDER PERSISTENT H5
RIDGE CNTRD ACRS E TX. HWVR RESPITE FM WET PATTN LIKELY FLEETING AS
SRN PLAINS RIDGE BLDS BACK NORTH AGAIN W/EWD FOLDING THETA-E RIDGE
XPCD DOWNSTREAM OF A SERIES OF AT TIMES CONVECTIVELY ENHANCED
DISTURBANCES EJECT OUT OF AMPLIFYING WRN US TROUGHING.
AS SUCH AND IN LIGHT OF GOOD INTERMODEL AGREEMENT REORDERED POPS/WX
FRI-SUN TO HIGHLIGHT BTR CHCS ACRS THE NORTH IN PROXIMITY TO IMPLIED
UPR JET STREAM ACRS LWR MI AND INVOF OSCILLATING SFC FNTL ZONE.
OTRWS VRY WARM TEMPS XPCD TO MANIFEST UNDERNEATH STEADILY NWD BLDG
UPR RIDGE AXIS AND NO DOUBT HOT...HUMID 90S LIKELY THIS WEEKEND.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON)
ISSUED AT 125 PM EDT MON JUL 13 2015
BOTH TERMINALS WILL BE ON THE NORTHEASTERN FRINGE OF THE BEST
THUNDERSTORM CHANCES THIS EVENING. THEREFORE HAVE KEPT ONLY A VCTS
MENTION AT THIS TIME. SCATTERED TO BROKEN CUMULUS FIELD EXPECTED
TO DEVELOP AHEAD OF THESE STORMS DURING THE LATE AFTERNOON/EARLY
EVENING WITH BASES BETWEEN 2KFT AND 3KFT. ANY STORMS WHICH DO
DEVELOP MAY BE SEVERE WITH STRONG WIND GUSTS. WILL AMEND TAF AS
NEEDED THIS EVENING IF EITHER TERMINAL APPEARS TO BE IMPACTED BY
STORMS.
&&
.IWX WATCHES/WARNINGS/ADVISORIES...
IN...FLASH FLOOD WATCH UNTIL 2 AM EDT /1 AM CDT/ TUESDAY FOR INZ003-
012-013-015-020-022>027-032>034.
MI...NONE.
OH...NONE.
LM...NONE.
&&
$$
SYNOPSIS...MCD
SHORT TERM...BENTLEY
LONG TERM...T
AVIATION...BENTLEY
VISIT US AT WWW.WEATHER.GOV/IWX (ALL LOWER CASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
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AREA FORECAST DISCUSSION
NWS NORTHERN INDIANA
318 PM EDT MON JUL 13 2015
.SYNOPSIS...
ISSUED AT 1133 AM EDT MON JUL 12 2015
THUNDERSTORMS ARE EXPECTED TO DEVELOP ACROSS THE AREA LATER THIS
AFTERNOON AND EVENING WITH SEVERE WEATHER POSSIBLE ALONG AND SOUTH
OF US 30. AFTERNOON HIGHS WILL BE AROUND 80 IN SOUTH CENTRAL
MICHIGAN TO THE UPPER 80S INTO NORTHWEST AND WEST CENTRAL INDIANA.
&&
.SHORT TERM...(THIS EVENING THROUGH TUESDAY)
ISSUED AT 316 PM EDT MON JUL 13 2015
RAPID DESTABILIZATION HAS BEGUN ACROSS NORTHERN ILLINOIS AS EXPECTED
AT 18Z THIS AFTERNOON. THIS DESTABILIZATION WILL CONTINUE TO ADVECT
EASTWARD THROUGH THE AFTERNOON WITH THE WESTERN HALF OF OUR FORECAST
AREA INTO THE WARM SECTOR BY EARLY EVENING. 18Z DVN SPECIAL SOUNDING
SAMPLED NEARLY DRY ADIABATIC LAPSE RATES FROM H850 TO H500 AND
NEARLY 100 KNOTS OF FLOW ABOVE 300MB. WITH SURFACE TEMPERATURES IN
THE MID 80S AND DEWPOINTS IN THE UPPER 70S BENEATH THIS EML...EXPECT
EXTREME INSTABILITY OF 4000 TO 6000 J/KG BY 22Z. THIS INSTABILITY
COUPLED WITH DEEP LAYER SHEAR OF 55 TO 65 KNOTS WILL LEAD TO
EXPLOSIVE STORM DEVELOPMENT AND ORGANIZATION LATER THIS EVENING. HP
SUPERCELLS WILL BE THE PRIMARY STORM MODE FOR THE FIRST FEW HOURS
BEFORE STORMS CONGEAL INTO A FORWARD PROPAGATING MCS.
DURING THIS 22Z TO 02Z TIMEFRAME...SURFACE WINDS WILL REMAIN OUT OF
THE SSW WITH A STRENGTHENING WESTERLY LOW LEVEL JET. EXTREMELY LOW
LCLS COUPLED WITH THIS STRONG LOW LEVEL SHEAR WILL LEAD TO AN
ENHANCED TORNADIC RISK DURING THIS TIMEFRAME. ADDITIONALLY...A
STRONG TORNADO CANNOT BE RULED OUT...ESPECIALLY IF STRONGER 850 FLOW
(35 TO 40 KNOTS) FROM THE LATEST HRRR VERIFIES.
EACH RUN OF THE HRRR HAS ADVECTED THE WARM FRONT PROGRESSIVELY
FURTHER EAST...SO CANNOT RULE OUT A GREATER THREAT FURTHER NORTHEAST
THAN THE CURRENT AREA OF FOCUS WHICH IS ALONG AND SOUTH OF US 30 IN
INDIANA.
MOST OF THE CWA RECEIVED BETWEEN 1 AND 1.5 INCHES WITH THE ROUND OF
RAIN THIS MORNING. FLASH FLOODING APPEARS INCREASINGLY LIKELY THIS
EVENING WITH A VERY HIGH THETA E AIRMASS AND TRAINING STORMS
POSSIBLE. THEREFORE...WILL KEEP THE FLASH FLOOD WATCH IN EFFECT
THROUGH 06Z.
ONCE THESE STORMS MOVE THROUGH...ADDITIONAL STORMS ARE POSSIBLE LATE
TONIGHT AND INTO THE DAY TOMORROW AS THE FRONT DROPS SOUTH THROUGH
OUR AREA. EXPECT THE FRONT TO MOVE SOUTH OF OUR FORECAST AREA BEFORE
ENOUGH INSTABILITY DEVELOPS FOR SEVERE WEATHER WITHIN OUR CWA.
&&
.LONG TERM...(TUESDAY NIGHT THROUGH MONDAY)
ISSUED AT 316 PM EDT MON JUL 13 2015
ROBUST NRN STREAM DISTURBANCE OVR NRN MN WILL DIG SEWD
INTO THE ERN LAKES ON TUE. RESULTING TROUGH AMPLIFICATION ACRS THE
LAKES WILL SHUNT UNSTABLE LL THETA-E RIDGE SWWD UNDER PERSISTENT H5
RIDGE CNTRD ACRS E TX. HWVR RESPITE FM WET PATTN LIKELY FLEETING AS
SRN PLAINS RIDGE BLDS BACK NORTH AGAIN W/EWD FOLDING THETA-E RIDGE
XPCD DOWNSTREAM OF A SERIES OF AT TIMES CONVECTIVELY ENHANCED
DISTURBANCES EJECT OUT OF AMPLIFYING WRN US TROUGHING.
AS SUCH AND IN LIGHT OF GOOD INTERMODEL AGREEMENT REORDERED POPS/WX
FRI-SUN TO HIGHLIGHT BTR CHCS ACRS THE NORTH IN PROXIMITY TO IMPLIED
UPR JET STREAM ACRS LWR MI AND INVOF OSCILLATING SFC FNTL ZONE.
OTRWS VRY WARM TEMPS XPCD TO MANIFEST UNDERNEATH STEADILY NWD BLDG
UPR RIDGE AXIS AND NO DOUBT HOT...HUMID 90S LIKELY THIS WEEKEND.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON)
ISSUED AT 125 PM EDT MON JUL 13 2015
BOTH TERMINALS WILL BE ON THE NORTHEASTERN FRINGE OF THE BEST
THUNDERSTORM CHANCES THIS EVENING. THEREFORE HAVE KEPT ONLY A VCTS
MENTION AT THIS TIME. SCATTERED TO BROKEN CUMULUS FIELD EXPECTED
TO DEVELOP AHEAD OF THESE STORMS DURING THE LATE AFTERNOON/EARLY
EVENING WITH BASES BETWEEN 2KFT AND 3KFT. ANY STORMS WHICH DO
DEVELOP MAY BE SEVERE WITH STRONG WIND GUSTS. WILL AMEND TAF AS
NEEDED THIS EVENING IF EITHER TERMINAL APPEARS TO BE IMPACTED BY
STORMS.
&&
.IWX WATCHES/WARNINGS/ADVISORIES...
IN...FLASH FLOOD WATCH UNTIL 2 AM EDT /1 AM CDT/ TUESDAY FOR INZ003-
012-013-015-020-022>027-032>034.
MI...NONE.
OH...NONE.
LM...NONE.
&&
$$
SYNOPSIS...BENTLEY
SHORT TERM...BENTLEY
LONG TERM...T
AVIATION...BENTLEY
VISIT US AT WWW.WEATHER.GOV/IWX (ALL LOWER CASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
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WWW.TWITTER.COM/NWSIWX
WWW.YOUTUBE.COM/NWSNORTHERNINDIANA
AREA FORECAST DISCUSSION
NWS NORTHERN INDIANA
125 PM EDT MON JUL 13 2015
.SYNOPSIS...
ISSUED AT 1133 AM EDT MON JUL 12 2015
THUNDERSTORMS ARE EXPECTED TO DEVELOP ACROSS THE AREA LATER THIS
AFTERNOON AND EVENING WITH SEVERE WEATHER POSSIBLE ALONG AND SOUTH
OF US 30. AFTERNOON HIGHS WILL BE AROUND 80 IN SOUTH CENTRAL
MICHIGAN TO THE UPPER 80S INTO NORTHWEST AND WEST CENTRAL INDIANA.
&&
.UPDATE...
ISSUED AT 1131 AM EDT MON JUL 13 2015
GROWING CONCERN FOR SIGNIFICANT SEVERE WEATHER THIS
AFTERNOON...MAINLY SOUTH OF US 30. TEMPERATURES HAVE ALREADY JUMPED
INTO THE UPPER 70S ACROSS NORTHERN ILLINOIS IN THE WAKE OF MORNING
CONVECTION. EXPECT TEMPERATURES TO RISE QUICKLY IN OUR AREA BY EARLY
AFTERNOON. FULL SUN FOR SEVERAL HOURS AND EFFICIENT
EVAPOTRANSPORATION SHOULD RESULT IN MODERATE TO EXTREME
DESTABILIZATION ALONG AND WEST OF A MICHIGAN CITY TO FORT WAYNE
LINE. LAST FEW RUNS OF THE HRRR HAVE SUPPORTED THIS THINKING WITH
STORMS DEVELOPING ALONG THIS FRONT BY LATE AFTERNOON. IF STORMS
DEVELOP IN THAT ENVIRONMENT...SUPERCELLS WILL BE THE PRIMARY STORM
MODE WITH 0-6 KM SHEAR IN EXCESS OF 50 KNOTS...STEEP MID LEVEL LAPSE
RATES...AND SIGNIFICANT TURNING OF THE WINDS WITH HEIGHT. TORNADOES
WILL ALSO BE POSSIBLE IN THIS SCENARIO GIVEN SOUTHERLY SURFACE WINDS
AND AN INCREASINGLY STRONG LOW LEVEL JET FROM THE WEST. MAY NEED TO
ADD SEVERE WORDING TO THE GRIDS WITHIN THE NEXT FEW HOURS IF
DESTABILIZATION BEGINS AS EXPECTED.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 458 AM EDT MON JUL 13 2015
INTERESTING CONDITIONAL SEVERE EPISODE IN THE MAKE WITH NOTABLE
VARIABLES WHICH INCLUDE ONGOING SEVERE UPSTREAM CONVECTION ACRS
SRN/CNTL WI AND RESULTANT OUTFLOWS/BOUNDARIES AND CONVECTIVE
RENEWAL TIMING UPSTREAM BY MID/LATE AFTN WITH LOW POTNL FOR
DUAL/CONSECUTIVE CONVECTIVE COMPLEXES WITH THE LATTER NOT TO TRACK
THROUGH REGION UNTIL EARLY TUE AM...SEVERAL HOURS AFTER FIRST.
WILL FOCUS PRIMARILY ON THE FIRST TWO EPISODES WITH MAINTENANCE OF
CONVECTION FAVORED ALONG SHARP INSTABILITY/ISODROSOTHERMAL
GRADIENT WHICH SHOULD FOCUS WI BOWING SEGMENT APEX OF WI SQUALL
LINE ADVANCEMENT MORE RIGHT/SRLY WITH TIME...ADVANCING INTO WRN
CWA AFTER 12 UTC. STRENGTHENING WNWLY STEERING FLOW SHOULD ALSO
ALLOW EWD SPREAD THROUGH SCNTL CWA THROUGH AM HOURS AS STORMS
BECOME ELEVATED INTO ERN FRINGES OF WARM ADVECTION LEAF. PRIMARY
COMPOSITE OUTFLOW CORE TO LIKELY EXTEND NW/SE FM NRN IL TO WCNTL
IN. ESTABLISHED RICH POOL OF LWR/MID 70S SFC DPS ACRS MID MS VLY
WITH ERN BOUNDARY THROUGH NERN IL TO SRN IN. AS UPSTREAM SWRLY
FLOW STRENGTHENS LATER TODAY STRONG THETA-E ADVECTION INTO
SWRN/SRN CWA...ENHANCED FURTHER BY EFFECTIVE CNTL IL
EVAPOTRANSPIRATIVE PROCESSES...WILL FOCUS STRONG SFC BASED
INSTABILITY RESERVOIR /5000+ J/KG IN SWEPT ARC S-SW- W-NW OF CWA
BY MID/LATE AFTN. MEANWHILE STRENGTHENING AND VEERING MID
TROPOSPHERIC FLOW TO 50-60KTS. FOCUS FOR INITIATION UPSTREAM ACRS
WI IN MID/LATE AFTN HOURS APPEARS TIED TO EJECTION OF DUMBELLED
SHORTWAVE FEATURE ACRS NRN MN TIED TO PRESENTLY REXED WAVE NEAR
ND/SASK/MAN BORDERS. AS LEAD SHORTWAVE ENTERS RAPID CONFLUENCY
BTWN HUDSON BAY VORTEX AND STOIC NRN TX RIDGE. SHOULD BE
SUFFICIENT INDUCEMENT TO CONVECT WITH SUBSEQUENT/RAPID
INTENSIFICATION...WITH EVOLUTION INTO LINEAR SEGMENT/S/ BY EVENING
AND ENTRY INTO NWRN/WRN CWA BYND 00 UTC. DEEP LYR SHEAR ON ORDER
OF 45 KTS FAR SWRN CWA TO 30 KTS NE ALONG WITH PRESENTATION OF
INSTABILITY FAVORS SWRN/SRN CWA FOR SEVERE WITH DAMAGING WIND
GUSTS LARGEST RISK GIVEN MID LEVEL SPEEDS ENTRAINED INTO REAR
INFLOWS. HIGHLY CONDITIONAL NATURE OF THIRD LATE PD 2 EPSIODE TOO
UNCERTAIN AND DWINDLE SCT TSRA/HIR SHRA POPS TO CHC BYND 06 UTC.
LACK OF STRONG DESTABILZATION DOWNSTREAM OF CONVECTION TRAVERSING
SRN LK MICHIGAN SHOULD KEEP STORMS ACRS NERN CWA BLO SVR LIMITS.
&&
.LONG TERM...(TUESDAY THROUGH SUNDAY)
ISSUED AT 458 AM EDT MON JUL 13 2015
LONG TERM FORECAST FAIRLY QUIET FROM A RELATIVE PERSPECTIVE. MAIN
VORTICITY LOBE AND ASSOCIATED SECONDARY LOW LEVEL FRONTAL BOUNDARY
WILL PUSH THROUGH OUR AREA DURING THE DAY TUESDAY. PRIMARY THETA-E
RIDGE LONG GONE BY THAT POINT BUT ENOUGH RESIDUAL MOISTURE TO TOUCH
OFF SCT/NUM SHOWERS...ESPECIALLY IN OUR SOUTHERN ZONES. ALSO SOME
MARGINAL INSTABILITY IN THOSE SOUTHERN COUNTIES SO WOULD NOT BE
SURPRISED TO SEE SOME EMBEDDED THUNDER. QPF AMOUNTS WILL BE FAIRLY
LIGHT BUT THE HIGHEST AMOUNTS (0.25-0.5 INCHES) WILL BE IN THE SOUTH
AND MAY PROLONG FLOODING DUE TO SHORT TERM CONVECTION.
WED/THURS STILL LOOKING DRY AS GREAT LAKES RECEIVE A HEALTHY DOSE OF
AVA/SUBSIDENCE IN THE WAKE OF DEPARTING TROUGH AXIS. NORTHEAST FLOW
WILL YIELD A SLIGHT COOL DOWN BUT THERMAL PROFILES NOT PARTICULARLY
COLD AND WILL BE AT LEAST PARTIALLY OFFSET BY A FAIR AMOUNT OF SOLAR
INSOLATION. KEPT HIGHS IN THE UPPER 70S TO AROUND 80F. RETURN TO
MORE ACTIVE WEATHER BY THE END OF THE WEEK AS A MUCH WARMER AND
MOISTURE-LADEN AIRMASS FOLDS BACK INTO THE OHIO VALLEY COURTESY OF
STALWART SOUTHERN PLAINS RIDGE. WESTERLY MID/UPPER LEVEL FLOW WILL
BRING ANOTHER PARADE OF LOW AMPLITUDE SYSTEMS INTO THE WEEKEND BUT
(NOT SURPRISINGLY) MEDIUM RANGE MODELS CONTINUE TO STRUGGLE
IMMENSELY WITH EXACT TIMING AND PLACEMENT. WILL CONTINUE TO HOLD
WITH LOW CHANCE POPS UNTIL DETAILS CAN BE SORTED OUT.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON)
ISSUED AT 125 PM EDT MON JUL 13 2015
BOTH TERMINALS WILL BE ON THE NORTHEASTERN FRINGE OF THE BEST
THUNDERSTORM CHANCES THIS EVENING. THEREFORE HAVE KEPT ONLY A VCTS
MENTION AT THIS TIME. SCATTERED TO BROKEN CUMULUS FIELD EXPECTED
TO DEVELOP AHEAD OF THESE STORMS DURING THE LATE AFTERNOON/EARLY
EVENING WITH BASES BETWEEN 2KFT AND 3KFT. ANY STORMS WHICH DO
DEVELOP MAY BE SEVERE WITH STRONG WIND GUSTS. WILL AMEND TAF AS
NEEDED THIS EVENING IF EITHER TERMINAL APPEARS TO BE IMPACTED BY
STORMS.
&&
.IWX WATCHES/WARNINGS/ADVISORIES...
IN...FLASH FLOOD WATCH THROUGH LATE TONIGHT FOR INZ003-012-013-015-
020-022>027-032>034.
MI...NONE.
OH...NONE.
LM...NONE.
&&
$$
UPDATE...BENTLEY
SYNOPSIS...MURPHY
SHORT TERM...MURPHY
LONG TERM...AGD
AVIATION...BENTLEY
VISIT US AT WWW.WEATHER.GOV/IWX (ALL LOWER CASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
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AREA FORECAST DISCUSSION
NWS MARQUETTE MI
349 PM EDT MON JUL 13 2015
.SHORT TERM...(THIS EVENING THROUGH TUESDAY)
ISSUED AT 340 PM EDT MON JUL 13 2015
UPPER AND SFC TROUGHS OVER THE AREA WILL BEGIN TO QUICKLY MOVE SE
TONIGHT AND TUE...BRINGING A COLD FRONT THROUGH THIS EVENING INTO
TONIGHT AHEAD OF A SFC RIDGE MOVING IN FROM THE NW. SHOWERS HAVE
BEEN ONGOING ACROSS PARTS OF THE AREA TODAY AND ARE NOW MAINLY
CONFINED TO MORE NRN PARTS OF UPPER MI AND LAKE SUPERIOR. EXPECT
SOME REDEVELOPMENT OF SCATTERED SHOWERS AND THUNDERSTORMS LATE THIS
AFTERNOON AND EVENING AS THE UPPER TROUGH AND SFC COLD FRONT MOVE
IN. COULD SEE A STRONGER STORM OR TWO OVER SRN UPPER MI...DEPENDING
ON CONVECTIVE DEVELOPMENT...AS RUC ANALYSIS SHOWS 500 TO AROUND
1000J/KG OF CAPE AROUND AROUND 20KTS OF EFFECTIVE SHEAR...BUT
CERTAINLY NOT EXPECTING SEVERE STORMS. USED A BLEND OF HIGH-RES
GUIDANCE THROUGH TUE WITH A HIGHER LEVEL OF UNCERTAINTY LATE THIS
AFTERNOON INTO TONIGHT DUE TO CONVECTION.
MARINE FOG WILL BE PUSHED ONSHORE BEHIND THE FRONT LATE THIS EVENING
AND TONIGHT...WITH RAIN SHOWERS FORMING IN UPSLOPE AREAS BEHIND THE
FRONT. EXPECT MOST OR ALL PRECIP TO BE DONE BY TUE AFTERNOON...BUT
DID LAG CLOUDS BACK FROM MODEL GUIDANCE AS CLEARING IS OFTEN SLOWER
THAN SHOWN BY MODELS. HIGHS ON TUE WILL BE IN THE 60S TO MID
70S...WARMEST SOUTH.
.LONG TERM...(TUESDAY NIGHT THROUGH MONDAY)
ISSUED AT 349 PM EDT MON JUL 13 2015
HIGH PRESSURE WILL CONTINUE TO BUILD OVER THE UPPER GREAT LAKES
REGION AT THE START OF THE LONG TERM PERIOD AND REMAIN IN PLACE
INTO WEDNESDAY NIGHT BEFORE SHIFTING TO THE EAST OF THE AREA ON
THURSDAY. THIS WILL LEAD TO A PERIOD OF DRY WEATHER AND BELOW NORMAL
TEMPERATURES FOR THE U.P. EXPECT SKIES TO BE MOSTLY CLEAR DURING
THIS PERIOD...ALTHOUGH THERE ARE HINTS OF SOME HIGH CLOUDS
STREAMING ACROSS THE AREA ON WEDNESDAY MORNING AND THEN A FEW
DIURNAL CU OVER THE WESTERN HALF OF THE U.P. ON WEDNESDAY
AFTERNOON.
ON THURSDAY...THE SURFACE RIDGE WILL BE DEPARTING BUT THERE WILL BE
ENOUGH DRY AIR IN PLACE TO LEAD TO ANOTHER NICE DAY ACROSS THE
AREA (TEMPERATURES RETURNING TO NORMAL). WILL LIKELY SEE INCREASING
HIGH CLOUDS THROUGH THE DAY AHEAD OF AN APPROACHING SHORTWAVE AND
BROAD SURFACE TROUGH THAT WILL MOVE THROUGH THE AREA THURSDAY NIGHT
INTO FRIDAY. MODELS FAIRLY CONSISTENT ON THIS IDEA...ALTHOUGH THEY
ARE VARYING ON THE TIMING/LOCATION OF THE BEST FORCING AS IT MOVES
THROUGH. WILL TRY TO SHOW A LITTLE BETTER TIMING...MAINLY IN THE
LATE THURSDAY NIGHT AND FRIDAY MORNING PERIOD...WITH THE WAVE
MOVING OUT OF THE AREA FRIDAY AFTERNOON/EVENING.
FRIDAY NIGHT INTO SATURDAY IS A LITTLE MORE UNCERTAIN...AS MODELS
ARE INCONSISTENT ON THE SUBTLE FEATURES (WHICH IS TO BE EXPECTED AT
5 DAYS OUT). OVERALL...IT APPEARS THAT A WEAK UPPER RIDGE WILL
SLIDE EAST ACROSS THE AREA ON SATURDAY AND WILL KEEP POPS BELOW
CLIMO FOR THIS TIME OF YEAR. IT DOES LOOK LIKE IT WILL BE
WARM/HUMID ON SATURDAY WITH HIGHS IN THE 80S AND DEWPOINTS IN THE
LOWER 60S. UNCERTAINTY REMAINS FOR THE SECOND HALF OF THE WEEKEND
AND INTO EARLY NEXT WEEK...AS THE MODELS ARE GIVING A VARIETY OF
SOLUTIONS FOR WAVE EJECTING EAST-NORTHEAST FROM THE UPPER TROUGH
OVER WESTERN CANADA AND POTENTIALLY THE PACIFIC NORTHWEST. WILL
FOLLOW A GENERAL CONSENSUS AT THIS POINT...WITH TEMPERATURES AT OR
SLIGHTLY ABOVE NORMAL.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON)
ISSUED AT 139 PM EDT MON JUL 13 2015
EXPECT SOME IMPROVEMENT THIS AFTERNOON/EVENING BEFORE LOW LEVEL
MOISTURE SURGES IN BEHIND A COLD FRONT. LOWERED CIGS WILL PERSIST
INTO TUE...WITH IMPROVEMENT EXPECTED TOWARD THE END OF THE 18Z TAF
PERIOD. AM STILL UNCERTAIN ON EXTENT/HEIGHT OF CIGS THIS
AFTERNOON/EVENING AND ALSO ON EXTENT OF SHOWERS AND MAYBE SOME
THUNDER. WENT WITH A CONSENSUS APPROACH FOR THE AFTERNOON/EVENING
GIVEN THAT DECREASED CONFIDENCE.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 340 PM EDT MON JUL 13 2015
A WEAK TROUGH MOVING THROUGH THE NRN LAKES TODAY INTO THIS EVENING
WILL KEEP WINDS BELOW 20 KNOTS. A COLD FRONT WILL DROP SOUTH ACROSS
LAKE SUPERIOR LATE TONIGHT...SHIFTING THE WINDS TO A NORTHERLY
DIRECTION. WINDS MAY INCREASE TO AROUND 20 KNOTS LATE TONIGHT INTO
TUE MORNING BEHIND THE FRONT BUT SHOULD DIMINISH TUE AFTERNOON. A
HIGH PRESSURE RIDGE WILL THEN MOVE OVER LAKE SUPERIOR FOR TUESDAY
NIGHT THROUGH WEDNESDAY NIGHT AND KEEP WINDS LIGHT.
AREAS OF FOG WILL CONTINUE TO AFFECT LAKE SUPERIOR INTO TONIGHT AS
WINDS REMAIN RELATIVELY LIGHT AND ABUNDANT LOW LEVEL MOISTURE
REMAINS OVER THE REGION. SO...THE DENSE FOG ADVY REMAINS IN EFFECT
THROUGH TONIGHT. AS DRIER AIR AND STRONGER MIXING ARRIVE LATER
TUESDAY INTO TUESDAY NIGHT BEHIND THE COLD FRONT...EXPECT THE FOG TO
DISSIPATE.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
DENSE FOG ADVISORY UNTIL 8 AM EDT TUESDAY FOR LSZ263-264-266.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...TITUS
LONG TERM...SRF
AVIATION...TITUS
MARINE...TITUS
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
340 PM EDT MON JUL 13 2015
.SHORT TERM...(THIS EVENING THROUGH TUESDAY)
ISSUED AT 340 PM EDT MON JUL 13 2015
UPPER AND SFC TROUGHS OVER THE AREA WILL BEGIN TO QUICKLY MOVE SE
TONIGHT AND TUE...BRINGING A COLD FRONT THROUGH THIS EVENING INTO
TONIGHT AHEAD OF A SFC RIDGE MOVING IN FROM THE NW. SHOWERS HAVE
BEEN ONGOING ACROSS PARTS OF THE AREA TODAY AND ARE NOW MAINLY
CONFINED TO MORE NRN PARTS OF UPPER MI AND LAKE SUPERIOR. EXPECT
SOME REDEVELOPMENT OF SCATTERED SHOWERS AND THUNDERSTORMS LATE THIS
AFTERNOON AND EVENING AS THE UPPER TROUGH AND SFC COLD FRONT MOVE
IN. COULD SEE A STRONGER STORM OR TWO OVER SRN UPPER MI...DEPENDING
ON CONVECTIVE DEVELOPMENT...AS RUC ANALYSIS SHOWS 500 TO AROUND
1000J/KG OF CAPE AROUND AROUND 20KTS OF EFFECTIVE SHEAR...BUT
CERTAINLY NOT EXPECTING SEVERE STORMS. USED A BLEND OF HIGH-RES
GUIDANCE THROUGH TUE WITH A HIGHER LEVEL OF UNCERTAINTY LATE THIS
AFTERNOON INTO TONIGHT DUE TO CONVECTION.
MARINE FOG WILL BE PUSHED ONSHORE BEHIND THE FRONT LATE THIS EVENING
AND TONIGHT...WITH RAIN SHOWERS FORMING IN UPSLOPE AREAS BEHIND THE
FRONT. EXPECT MOST OR ALL PRECIP TO BE DONE BY TUE AFTERNOON...BUT
DID LAG CLOUDS BACK FROM MODEL GUIDANCE AS CLEARING IS OFTEN SLOWER
THAN SHOWN BY MODELS. HIGHS ON TUE WILL BE IN THE 60S TO MID
70S...WARMEST SOUTH.
.LONG TERM...(TUESDAY THROUGH SUNDAY)
ISSUED AT 529 AM EDT MON JUL 13 2015
OUR OFF AND ON SHOWER/TS ACTIVITY WILL BE DIMINISHING SIGNIFICANTLY
AFTER TUESDAY MORNING...AND MAY BE MORE LIMITED THROUGH THE REST OF
THE FCST PERIOD IF THE NEXT COUPLE OF SYSTEMS ARE UNABLE TO BREAK
DOWN THE STUBBORN 500MB RIDGE ACROSS MUCH OF THE CENTRAL U.S.
EXPECT SOME BRIEF GUSTY WINDS TUESDAY AS THE DEEPENING SFC LOW OVER
N LOWER MI AT 12Z SINKS ACROSS LAKE ERIE...AND LARGE HIGH PRESSURE
PUSHES IN FROM CENTRAL CANADA. THIS WILL BE WHILE THE 500MB LOW OVER
N QUEBEC AND TROUGH EXTENDING ACROSS LOWER MI EXIT TOO.
PW VALUES WILL FALL FROM AN AVG 1.5IN AT 12Z TUESDAY TO 0.3IN
TUESDAY NIGHT AS 850MB TEMPS FALL TO AROUND 11C /FROM NEAR 16C/.
MODEL GUIDANCE FOLLOWS THIS TREND PRETTY WELL...AND LOWERING THE
OVERNIGHT TEMPS EVEN MORE FOR TUESDAY NIGHT MAY BE NECESSARY BY
LATER SHIFTS. CURRENTLY EXPECT TEMPS TO BOTTOM OUT IN THE MID 40S TO
RIGHT AROUND 50F...WARMEST ALONG THE GREAT LAKES SHORELINES. LOOK
FOR SLOWLY INCREASING MOISTURE DURING THE DAY WEDNESDAY. THE SFC
HIGH WILL BE DIRECTLY OVER UPPER MI WEDNESDAY AFTERNOON...BEFORE
SLOWLY CENTERING ACROSS LAKE HURON AND THE LOWER GREAT LAKES
THURSDAY AFTERNOON...AND THE NEW ENGLAND STATES THURSDAY EVENING.
A LARGE AREA OF HIGH PRESSURE OVER S CENTRAL AND THE N TO CENTRAL
PLAINS STATES THURSDAY EVENING WILL BE PRESENT THROUGH THE WEEKEND.
THE 500MB RIDGE ACROSS MUCH OF THE E TWO-THIRDS OF THE NATION LOOKS
TO BECOME MORE ZONAL OVER THE UPPER GREAT LAKES FRIDAY MORNING. THE
RIDGE WILL REBOUND SATURDAY. THERE ARE SOME SIGNIFICANT DIFFERENCES
BETWEEN THE GFS AND ECMWF LATE SUNDAY AFTERNOON INTO MONDAY. A
GENERAL MODEL BLEND LOOKS TO BE BEST THAT FAR OUT...WITH 20-40
PERCENT POPS.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON)
ISSUED AT 139 PM EDT MON JUL 13 2015
EXPECT SOME IMPROVEMENT THIS AFTERNOON/EVENING BEFORE LOW LEVEL
MOISTURE SURGES IN BEHIND A COLD FRONT. LOWERED CIGS WILL PERSIST
INTO TUE...WITH IMPROVEMENT EXPECTED TOWARD THE END OF THE 18Z TAF
PERIOD. AM STILL UNCERTAIN ON EXTENT/HEIGHT OF CIGS THIS
AFTERNOON/EVENING AND ALSO ON EXTENT OF SHOWERS AND MAYBE SOME
THUNDER. WENT WITH A CONSENSUS APPROACH FOR THE AFTERNOON/EVENING
GIVEN THAT DECREASED CONFIDENCE.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 340 PM EDT MON JUL 13 2015
A WEAK TROUGH MOVING THROUGH THE NRN LAKES TODAY INTO THIS EVENING
WILL KEEP WINDS BELOW 20 KNOTS. A COLD FRONT WILL DROP SOUTH ACROSS
LAKE SUPERIOR LATE TONIGHT...SHIFTING THE WINDS TO A NORTHERLY
DIRECTION. WINDS MAY INCREASE TO AROUND 20 KNOTS LATE TONIGHT INTO
TUE MORNING BEHIND THE FRONT BUT SHOULD DIMINISH TUE AFTERNOON. A
HIGH PRESSURE RIDGE WILL THEN MOVE OVER LAKE SUPERIOR FOR TUESDAY
NIGHT THROUGH WEDNESDAY NIGHT AND KEEP WINDS LIGHT.
AREAS OF FOG WILL CONTINUE TO AFFECT LAKE SUPERIOR INTO TONIGHT AS
WINDS REMAIN RELATIVELY LIGHT AND ABUNDANT LOW LEVEL MOISTURE
REMAINS OVER THE REGION. SO...THE DENSE FOG ADVY REMAINS IN EFFECT
THROUGH TONIGHT. AS DRIER AIR AND STRONGER MIXING ARRIVE LATER
TUESDAY INTO TUESDAY NIGHT BEHIND THE COLD FRONT...EXPECT THE FOG TO
DISSIPATE.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
DENSE FOG ADVISORY UNTIL 8 AM EDT TUESDAY FOR LSZ263-264-266.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...TITUS
LONG TERM...KF
AVIATION...TITUS
MARINE...TITUS
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
140 PM EDT MON JUL 13 2015
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 507 AM EDT MON JUL 13 2015
WV IMAGERY AND RAP ANALYSIS INDICATED A BORAD MID/UPPER LEVEL RIDGE
CENTERED OVER THE SRN PLAINS AND A TROUGH OVER SRN MANITOBA. AT THE
SFC...A FRONTAL BOUNDARY FROM SE NORTH DAKOTA THROUGH SE MN INTO NRN
IL. THE STRONGEST CONVECTION WITH A LARGE MCS THAT DEVELOPED OVER MN
HAS SLIDE SE INTO CNTRL/SRN WI ALONG AND NORTH OF THE FRONT AND
MUCAPE GRADIENT. SHOWERS AND EMBEDDED TSRA ASSOCIATED WITH THE
LEFTOVER MCV PERSISTED INTO WRN LAKE SUPERIOR AND WRN UPPER MI.
TODAY...RADR TRENDS AND SHORT RANGE HIGH RES MODELS SUGGEST THAT THE
SHRA/TSRA OVER WRN UPPER MI WILL CONTINUE TO GRADUALLY SLIDE TO THE
EAST EARLY THIS MORNING WHILE ALSO WEAKENING AS THE PCPN MOVES AWAY
FROM THE AREA OF GREATER INSTABILITY. HOWEVER...THE APPROACH OF A
WEAK SHRTWV IN ADVANCE OF THE MANITOBA TROUGH MAY RESULT IN
ADDITIONAL DEVELOPMENT BY LATE MORNING INTO THE EARLY AFTERNOON AS
DAYTIME HEATING INCREASES AND A WEAK SFC TROUGH MOVES THROUGH THAT
COULD ALSO INTERACT WITH LAKE BREEZE BOUNDARIES. OVERALL CONFIDENCE
IN PCPN TIMING/COVERAGE IS LOW GIVEN MODEL DIFFERENCES AND LINGERING
EFFECTS OF THE LARGE MCS. WITH FCST MLCAPE VALUES ONLY INTO THE 500-
1000 J/KG RANGE AND WEAK 0-6KM/0-1KM SHEAR MAINLY JUST BRIEF HEAVY
RAIN WOULD BE THE MAIN HAZARD.
TONIGHT...EXPECT THE MID LEVEL TROUGH INTO THE NRN LAKES TO
GRADUALLY SINK OFF TO THE SE. WITH THE LOSS OF DAYTIME INSTABILITY
AND ANY WEAK MID LEVEL FORCING WITH THE TROUGH...SHRA/TSRA WILL
DIMINISH FROM THE NW OVERNIGHT. THERE MAY BE SOME SHOWERS LATE INTO
THE NORTH AS THE COLD FRONT SLIDES INTO THE AREA.
.LONG TERM...(TUESDAY THROUGH SUNDAY)
ISSUED AT 529 AM EDT MON JUL 13 2015
OUR OFF AND ON SHOWER/TS ACTIVITY WILL BE DIMINISHING SIGNIFICANTLY
AFTER TUESDAY MORNING...AND MAY BE MORE LIMITED THROUGH THE REST OF
THE FCST PERIOD IF THE NEXT COUPLE OF SYSTEMS ARE UNABLE TO BREAK
DOWN THE STUBBORN 500MB RIDGE ACROSS MUCH OF THE CENTRAL U.S.
EXPECT SOME BRIEF GUSTY WINDS TUESDAY AS THE DEEPENING SFC LOW OVER
N LOWER MI AT 12Z SINKS ACROSS LAKE ERIE...AND LARGE HIGH PRESSURE
PUSHES IN FROM CENTRAL CANADA. THIS WILL BE WHILE THE 500MB LOW OVER
N QUEBEC AND TROUGH EXTENDING ACROSS LOWER MI EXIT TOO.
PW VALUES WILL FALL FROM AN AVG 1.5IN AT 12Z TUESDAY TO 0.3IN
TUESDAY NIGHT AS 850MB TEMPS FALL TO AROUND 11C /FROM NEAR 16C/.
MODEL GUIDANCE FOLLOWS THIS TREND PRETTY WELL...AND LOWERING THE
OVERNIGHT TEMPS EVEN MORE FOR TUESDAY NIGHT MAY BE NECESSARY BY
LATER SHIFTS. CURRENTLY EXPECT TEMPS TO BOTTOM OUT IN THE MID 40S TO
RIGHT AROUND 50F...WARMEST ALONG THE GREAT LAKES SHORELINES. LOOK
FOR SLOWLY INCREASING MOISTURE DURING THE DAY WEDNESDAY. THE SFC
HIGH WILL BE DIRECTLY OVER UPPER MI WEDNESDAY AFTERNOON...BEFORE
SLOWLY CENTERING ACROSS LAKE HURON AND THE LOWER GREAT LAKES
THURSDAY AFTERNOON...AND THE NEW ENGLAND STATES THURSDAY EVENING.
A LARGE AREA OF HIGH PRESSURE OVER S CENTRAL AND THE N TO CENTRAL
PLAINS STATES THURSDAY EVENING WILL BE PRESENT THROUGH THE WEEKEND.
THE 500MB RIDGE ACROSS MUCH OF THE E TWO-THIRDS OF THE NATION LOOKS
TO BECOME MORE ZONAL OVER THE UPPER GREAT LAKES FRIDAY MORNING. THE
RIDGE WILL REBOUND SATURDAY. THERE ARE SOME SIGNIFICANT DIFFERENCES
BETWEEN THE GFS AND ECMWF LATE SUNDAY AFTERNOON INTO MONDAY. A
GENERAL MODEL BLEND LOOKS TO BE BEST THAT FAR OUT...WITH 20-40
PERCENT POPS.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON)
ISSUED AT 139 PM EDT MON JUL 13 2015
EXPECT SOME IMPROVEMENT THIS AFTERNOON/EVENING BEFORE LOW LEVEL
MOISTURE SURGES IN BEHIND A COLD FRONT. LOWERED CIGS WILL PERSIST
INTO TUE...WITH IMPROVEMENT EXPECTED TOWARD THE END OF THE 18Z TAF
PERIOD. AM STILL UNCERTAIN ON EXTENT/HEIGHT OF CIGS THIS
AFTERNOON/EVENING AND ALSO ON EXTENT OF SHOWERS AND MAYBE SOME
THUNDER. WENT WITH A CONSENSUS APPROACH FOR THE AFTERNOON/EVENING
GIVEN THAT DECREASED CONFIDENCE.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 515 AM EDT MON JUL 13 2015
A WEAK TROUGH MOVING THROUGH THE NRN LAKES TODAY INTO THIS EVENING
WILL KEEP WINDS BELOW 20 KNOTS. A COLD FRONT WILL DROP SOUTH ACROSS
LAKE SUPERIOR LATE TONIGHT...SHIFTING THE WINDS TO A NORTHERLY
DIRECTION. WINDS MAY INCREASE TO AROUND 20 KNOTS LATE TONIGHT INTO
TUE MORNING BEHIND THE FRONT BUT SHOULD DIMINISH TUE AFTERNOON. A
HIGH PRESSURE RIDGE WILL THEN MOVE OVER LAKE SUPERIOR FOR TUESDAY
NIGHT THROUGH WEDNESDAY NIGHT AND KEEP WINDS LIGHT.
AREAS OF FOG WILL CONTINUE TO AFFECT LAKE SUPERIOR TODAY INTO
TONIGHT AS WINDS REMAIN RELATIVELY LIGHT AND ABUNDANT LOW LEVEL
MOISTURE REMAINS OVER THE REGION. SO...THE DENSE FOG ADVY REMAINS IN
EFFECT THROUGH TONIGHT. AS DRIER AIR AND STRONGER MIXING ARRIVE
LATER TUESDAY INTO TUESDAY NIGHT BEHIND THE COLD FRONT...EXPECT THE
FOG TO DISSIPATE.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
DENSE FOG ADVISORY UNTIL 8 AM EDT TUESDAY FOR LSZ263-264-266.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...JLB
LONG TERM...KF
AVIATION...TITUS
MARINE...JLB
AREA FORECAST DISCUSSION
NWS SPRINGFIELD MO
544 PM CDT Mon Jul 13 2015
.SHORT TERM...(This Evening through Tuesday)
Issued at 215 PM CDT MON JUL 13 2015
High pressure remained in control of the Ozarks weather today with
most locations across the region seeing afternoon temperatures in
in the upper 80s to lower 90s. Heat index values along and north
of I-44 were in from 100 to 108.
The region will remain on the eastern edge of the upper level
ridge overnight tonight and again on Tuesday. This will allow
temperatures and heat index values to reach similar levels seen
today, though probably a degree or two cooler. Despite this
slightly cooler expectation, heat index values should still climb
into the 100 to 106 degree range across the current heat advisory
area. AS a result will extend the heat advisory through 00z
Tuesday.
Mesoscale models have also been hinting at the convection ongoing
across SE Nebraska and NE Kansas continuing through this evening
and overnight and sagging into central SW Missouri. The concern is
that the ongoing convection can get a small cold pool going and
ride south into the Ozarks along the eastern edge of the 700mb
ridge. The primary concern would be strong straight line winds
with very large available CAPE and weak shear. Have increased rain
chances as a result but did not go more than slight/chance pops
due to continued uncertainty if the cold pool will form. This
will be a short term concern going into this evening and
overnight.
The issues for tonight and Tuesday boil down to the continuation
of the heat advisory through early Tuesday evening and potential
convection this evening and overnight. Cloud cover from the
potential storms would then potentially impact temperatures
Tuesday and a lingering surface/low level boundary may allow for
moisture pooling across central Missouri, which may locally
enhance heat index values.
.LONG TERM...(Tuesday Night through Monday)
Issued at 215 PM CDT MON JUL 13 2015
Upper ridge over the southern and central plains to flatten into
zonal flow bringing marginal but still welcome relief from the
bout of heat. Of greater note will be the lowered dew points as
winds shift in response to Canadian high pressure descending into
the Great Lakes Wednesday.
Models depict some scattered TSRA along a developing warm front
late Wednesday into Thursday but confidence is modest on how
widespread this rainfall will be.
Chances for precipitation then look to be largely west and north
of the region into the weekend as the northern stream looks to
remain active.
&&
.AVIATION...(For the 00Z TAFS through 00Z Tuesday Evening)
Issued at 540 PM CDT MON JUL 13 2015
Strong to severe convection beginning to develop along boundary
north and northwest of the CWA. Very unstable atmosphere in area
where initiation is occuring. HRRR seems to be handling this
fairly well and with cold pool development would take storms to
the south and into the cwa this evening. Have main convection
remaining north and east of the forecast TAF points but with
boundary moving into the area overnight, did put some VCTS in for
SGF/JLN towards morning. Will have some low level wind shear
during the overnight hours.
&&
.SGF WATCHES/WARNINGS/ADVISORIES...
MO...HEAT ADVISORY until 7 PM CDT Tuesday FOR MOZ055>058-066>071-
077>081-088>090-093-094-101.
KS...HEAT ADVISORY until 7 PM CDT Tuesday FOR KSZ073-097-101.
&&
$$
SHORT TERM...Hatch
LONG TERM...Runnels
AVIATION...Lindenberg
AREA FORECAST DISCUSSION...UPDATED AVIATION
NWS ST LOUIS MO
534 PM CDT MON JUL 13 2015
.SHORT TERM: (THROUGH LATE TONIGHT)
ISSUED AT 410 PM CDT MON JUL 13 2015
HEAT ADVISORY CONTINUES ACROSS THE ENTIRE AREA UNTIL LATER THIS
EVENING WITH SURFACE TEMPERATURES IN THE 90S AND DEW POINTS IN THE
70S THIS AFTERNOON. HEAT INDICES WERE MAINLY FROM 100 TO 110,
TOPPING OUT AT 113 AT LAMBERT FIELD. CONVECTION CONTINUES TO
DEVELOP ACROSS NORTHERN MO ON THE NORTHERN FRINGES OF THE CAP AND
AHEAD OF A COLD FRONT WHICH EXTENDS FROM NORTHWESTERN WI SOUTHWEST
INTO CENTRAL KS. CONVECTION WILL CONTINUE TO DEVELOP TONIGHT AS THE
FRONT SINKS SLOWLY SOUTHWARD INTO OUR AREA AND THE CAP GRADUALLY
WEAKENS. WITH EXTREME INSTABILITY AND AMPLE WIND SHEAR SOME OF THE
STORMS WILL BE SEVERE WITH DAMAGING WINDS BEING THE MOST LIKELY
HAZARD. MOST OF THE CONVECTION WILL BE ACROSS NORTHEAST MO AND WEST
CENTRAL IL THIS EVENING, THEN SHIFT SOUTHWARD INTO CENTRAL AND
SOUTHEAST MO AND SOUTHWEST ILLINOIS LATE TONIGHT. SLIGHTLY COOLER
CONDITIONS CAN BE EXPECTED ACROSS NORTHEAST MO LATE TONIGHT BEHIND
THE COLD FRONT, WITH CONTINUED WARM AND MUGGY CONDITIONS ELSEWHERE.
GKS
.LONG TERM: (TUESDAY THROUGH NEXT MONDAY)
ISSUED AT 410 PM CDT MON JUL 13 2015
UPPER LEVEL HIGH CENTERED OVER THE SOUTH-CENTRAL CONUS WILL MOVE
LITTLE OVER THE NEXT SEVEN DAYS...BUT ITS DOMINANCE OVER OUR REGION
WILL WAX AND WANE AT TIMES.
THIS UPPER LEVEL HIGH WILL LOSE SOME OF ITS INFLUENCE BEGINNING
TUESDAY AND THIS WILL BE ACCOMPANIED BY PASSAGE OF THE MAIN COLD
FRONT. HOWEVER...THIS COLD FRONTAL PASSAGE WILL COME TOO LITTLE TOO
LATE FOR MANY AREAS WITH W-SW WINDS EXPECTED THRU MUCH OF THE DAY
AND IN THE WAKE OF THE LEFTOVER CONVECTION FROM THE PRE-FRONTAL TROF
THE NIGHT BEFORE...MANY AREAS SHOULD SEE DECENT SUNSHINE RETURN.
MOS TEMPS SEEM TO HAVE A GOOD HANDLE ON THIS WITH A RETURN OF MID
90S TEMPS AND COUPLED WITH DEWPOINTS IN THE LOW-MID 70S WILL RESULT
IN HEAT INDICES BETWEEN 100-105 FOR A FOURTH CONSECUTIVE DAY FOR THE
CORRIDOR BETWEEN COU/JEF AND STL METRO. HAVE EXTENDED IN TIME THRU
EARLY TUESDAY EVENING THE HEAT ADVISORY FOR THIS AREA WITH POSSIBLE
AREAL EXPANSION ELSEWHERE ON TUESDAY. FOR NOW...THE HEAT ADVISORY
EXPIRES ELSEWHERE AT 9PM THIS EVENING.
COOLER TEMPS THEN TAKE HOLD FOR A COUPLE OF DAYS ON WEDNESDAY AND
THURSDAY PROVIDING SOME RELIEF AND KEEPING MAX TEMPS IN THE 80S FOR
MOST AREAS WITH LOWER HUMIDITIES.
THE HEAT AND HUMIDITY IS SET TO RETURN FOR FRIDAY AND THRU EARLY
NEXT WEEK WITH POSSIBLE RE-ISSUANCE OF HEAT HEADLINES.
OTHERWISE...RAIN CHANCES LOOK MEAGER FOR MUCH OF THIS PERIOD WITH
EITHER THE MAIN FOCUS TO OUR SOUTH IN THE CASE OF WEDNESDAY...AND A
WELL CAPPED ATMOSPHERE FOR FRIDAY THRU NEXT MONDAY. THE BEST
CHANCES WILL BE WEDNESDAY NIGHT AND THURSDAY WITH A WARM FRONT
BUCKLING BACK NORTH. DESPITE THE MAIN COLD FRONT MOVING THRU
TUESDAY AFTERNOON...THE PRE-FRONTAL TROF STEALS THE SHOW JUST ENOUGH
WITH MOISTURE TO ALLOW THE CAP TO LIKELY MAINTAIN THRU MUCH OF ITS
PASSAGE THRU THE FORECAST AREA.
TES
&&
.AVIATION: (FOR THE 00Z TAFS THROUGH 00Z TUESDAY EVENING)
ISSUED AT 520 PM CDT MON JUL 13 2015
WEAK BOUNDARY, MORE OF A WIND SHIFT WITH A PRE-FRONTAL TROF, LIES
ACROSS NORTHERN MO. ONE BIG THUNDERSTORM AND SOEM SHOWERS ARE
MOVING EAST SOUTHEAST NEAR THIS BOUNDARY. SURFACE HEATING AND
ABUNDANT INSTABILITY LIKELY THE DRIVING FACTOR. HRRR BLOWS UP THE
LINE AND MOVE IT SOUTH. RAP AND THE LONGER TERM MODELS DO NOT,
KILLING IT AND THEN REDEVELOPING ABOUT 10Z ACROSS CENTRAL TO
EASTERN MO. THIS SCENARIO LOOKS BETTER GIVEN THE CAP AND CURRENT
TREND OF THE RAIN SHRINKING (EXCEPT FOR THE ONE STORM. BOUNDARY
WILL CONTINUE SOUTH WITH THE REAL COLD FRONT ARRIVING TUESDAY
AFTERNOON.
SPECIFICS FOR KSTL: NOT HIGH ON THE HRRR SOLUTION SO AM PRETTY MUCH
FOLLOWING THE NAM AND OTHER MODELS WHICH ARE IN BETTER AGREEMENT.
WILL WATCH THE CURRENT RAIN AND MAY NEED A VCSH/VCTS SOMETIME
THIS EVENING. OTHERWISE WILL PUT ANOTHER VCTS ABOUT 09-10Z BASED
ON THE NAM AND RAP. CAP SHOULD BE WEAKER BY THEN. WEST WIND
TUESDAY GOING NORTHWEST LATE IN THE AFTERNOON.
JPK
&&
.LSX WATCHES/WARNINGS/ADVISORIES:
MO...HEAT ADVISORY UNTIL 9 PM CDT THIS EVENING FOR CRAWFORD MO-IRON
MO-KNOX MO-LEWIS MO-MADISON MO-MARION MO-MONROE MO-PIKE MO-
RALLS MO-REYNOLDS MO-SHELBY MO-ST. FRANCOIS MO-WASHINGTON
MO.
HEAT ADVISORY UNTIL 8 PM CDT TUESDAY FOR AUDRAIN MO-BOONE MO-
CALLAWAY MO-COLE MO-FRANKLIN MO-GASCONADE MO-JEFFERSON MO-
LINCOLN MO-MONITEAU MO-MONTGOMERY MO-OSAGE MO-ST. CHARLES
MO-ST. LOUIS CITY MO-ST. LOUIS MO-STE. GENEVIEVE MO-WARREN
MO.
IL...HEAT ADVISORY UNTIL 9 PM CDT THIS EVENING FOR ADAMS IL-BOND IL-
BROWN IL-CLINTON IL-FAYETTE IL-GREENE IL-MACOUPIN IL-MARION
IL-MONTGOMERY IL-PIKE IL-WASHINGTON IL.
HEAT ADVISORY UNTIL 8 PM CDT TUESDAY FOR CALHOUN IL-JERSEY IL-
MADISON IL-MONROE IL-RANDOLPH IL-ST. CLAIR IL.
&&
$$
WFO LSX
AREA FORECAST DISCUSSION
NWS OMAHA/VALLEY NE
1226 PM CDT MON JUL 13 2015
.UPDATE...
ISSUED AT 1222 PM CDT MON JUL 13 2015
CONVECTION CONTINUES TO FIRE ACROSS SOUTHEAST NEBRASKA...ALONG THE
WIND SHIFT/PRESSURE CONVERGENCE LINE. ISOLATED SHOWERS WERE ALSO
NOTED ACROSS SOUTHWEST IOWA. OTHERWISE...DRIER AIR IS MOVING INTO
THE REGION WITH DEWPOINTS NOW DOWN INTO THE MID TO UPPER 60S
ALONG/NORTH OF I80. MID TO UPPER 70S DEWPOINTS PERSIST ACROSS
SOUTHEAST NEBRASKA AND SOUTHWEST IOWA. WILL LEAVE ONGOING HEAT
ADVISORY IN PLACE FOR NOW...BUT THE NORTHERN FRINGE ALONG I80 MAY
NOT REMAIN IN CRITERIA VERY LONG IF DEWPOINTS DROP JUST A BIT MORE.
&&
.SHORT TERM...(TODAY THROUGH WEDNESDAY)
ISSUED AT 310 AM CDT MON JUL 13 2015
HEAT AND HUMIDITY TODAY...ISOLATED STORMS INTO MID MORNING AND
THEN SLIGHT CHANCE OF TSTMS LATE TODAY INTO THIS EVENING ARE THE
PRIMARY FORECAST CONCERNS THROUGH THIS PERIOD.
UPPER AIR CHARTS FROM LAST EVENING SHOWED THE FOLLOWING. AT 300 MB
A JET STREAK OF 80-90 KNOTS EXTENDED FROM ERN WY ACROSS SRN SD. AT
500 MB...WEAK HEIGHT FALLS WERE MOVING EWD ACROSS THE DAKOTAS AND
MN AND RIDGE ALOFT WAS STILL CENTERED OVER TX. THERMAL RIDGE AT
700 MB STRETCHED FROM NM INTO CO AND KS. ACROSS NEBRASKA...700 MB
TEMPERATURES WERE GENERALLY 12-13 DEGREES C. THERMAL RIDGE AT 850
MB WAS LOCATED FROM NM INTO WRN SD. DRIER AIR WAS OVER THE HIGH
PLAINS BUT 850 MB DEWPOINTS WERE IN THE TEENS FROM IA BACK INTO
ERN NE. THE KOAX SOUNDING FROM 00Z WAS FAIRLY MOIST...WITH A
PRECIPITABLE WATER OF 1.48 INCHES. SURFACE ANALYSIS AT 08Z SHOWED
A TROUGH OF LOW PRESSURE CURVING FROM THE ERN SD INTO NWRN KS.
AHEAD OF THIS TROUGH...DEWPOINTS WERE MOSTLY IN THE 70S BUT DROP
TO 60S AND 50S WEST OF THE TROUGH.
JUST HOW FAST DRIER AIR WILL BE ABLE TO MOVE IN TODAY WILL HAVE A
BIG IMPACT ON HEAT INDICES. LEFT PREVIOUSLY ISSUED HEAT ADVISORY
AS IS...BUT MAY NEED A SLIGHT ADJUSTMENT LATER TODAY. OTHERWISE...
ISOLATED TSRA WERE OCCURRING OVER PARTS OF NERN NE. THESE WERE
VERY HIGH BASED...ABOVE THE MID LEVEL CAP AND POSSIBLY GETTING
SOME SUPPORT BY THE JET STREAK MENTIONED EARLIER AND VERY WEAK
MID LEVEL HEIGHT FALLS. THESE MAY LAST INTO MID MORNING AS THEY
CONTINUE TO TRACK EAST. AFTER THAT...THE REST OF THE DAY IS
EXPECTED TO BE DRY...EXCEPT DID INCLUDE A SLIGHT CHANCE OF TSTMS
IN OUR FAR SRN COUNTIES TOWARD 6 PM AND THEN THROUGH EARLY THIS
EVENING. HRRR AND SOME OF THE OTHER HIGH RESOLUTION MODELS HAVE
GENERALLY BEEN TOO BULLISH WITH STORM DEVELOPMENT/COVERAGE THE
PAST FEW DAYS...BUT WEAK SIGNALS ARE THERE FOR POSSIBLE ISOLATED
ACTIVITY LATER TODAY. KEPT HIGHS CLOSE TO PREVIOUS FORECAST...
IN THE MID AND UPPER 90S.
THE 00Z GFS DEVELOPED MORE PCPN OVERNIGHT ALONG THE KS/NE BORDER
BUT FELT THAT WAS OVERDONE AT THIS POINT. HAVE MOST OF THE AREA
DRY OVERNIGHT WITH LOWS IN THE MID OR UPPER 60S NORTH AND LOWER
70S SOUTH. RIGHT NOW...TUESDAY LOOKS TO BE A FEW DEGREES COOLER
THAN TODAY...WITH HEAT INDICES STAYING MAINLY BELOW 100.
RAIN CHANCES START TO INCREASE TUESDAY NIGHT AND THEN MORE ON
WEDNESDAY AS HEIGHTS DECREASE A BIT. THIS WILL ALLOW SHORTWAVE
ENERGY TO MOVE OUT OF THE WESTERN UNITED STATES TROUGH AND TAP
INTO SOME MONSOONAL MOISTURE. DUE TO MORE CLOUD COVER...HAVE
HIGHS WEDNESDAY MAINLY 85 TO 90.
.LONG TERM...(WEDNESDAY NIGHT THROUGH SUNDAY)
ISSUED AT 310 AM CDT MON JUL 13 2015
500 MB RIDGE WILL GENERALLY REMAIN CENTERED OVER LA OR ERN TX
THROUGH THIS PERIOD. OUR AREA WILL BE MOSTLY IN SOUTHWEST MID
LEVEL FLOW...AHEAD OF THE TROUGH LOCATED MAINLY ACROSS THE PACIFIC
NORTHWEST. TEMPERATURES WILL GENERALLY BE SEASONAL WITH OCCASIONAL
SMALL CHANCES FOR PCPN. BEST CHANCES LOOK TO BE WEDNESDAY NIGHT
INTO THURSDAY AND THEN AGAIN SUNDAY NIGHT.
&&
.AVIATION...(18Z TAFS FOR KOFK...KLNK AND KOMA.)
ISSUED AT 1222 PM CDT MON JUL 13 2015
VFR CONDITIONS THROUGH THE PERIOD WITH NORTHWEST FLOW AT ALL
SITES...BECOMING LIGHT AND VARIABLE BY 23-00Z.
&&
.OAX WATCHES/WARNINGS/ADVISORIES...
NE...HEAT ADVISORY UNTIL 8 PM CDT THIS EVENING FOR NEZ045-051>053-
066>068-078-088>093.
IA...HEAT ADVISORY UNTIL 8 PM CDT THIS EVENING FOR IAZ055-056-069-079-
080-090-091.
&&
$$
UPDATE...DEWALD
SHORT TERM...MILLER
LONG TERM...MILLER
AVIATION...DEWALD
AREA FORECAST DISCUSSION
NWS RALEIGH NC
335 PM EDT MON JUL 13 2015
.SYNOPSIS...AN INCREASINGLY ACTIVE NORTHWEST FLOW ALOFT WILL
BRING A SERIES OF DISTURBANCES ACROSS THE REGION THROUGH MIDWEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 335 PM MONDAY...
A SERIES OF DISTURBANCES ALOFT WILL CAUSE A L/W TROUGH TO AMPLIFY
OVER THE EASTERN U.S. THROUGH MID WEEK. THIS AMPLIFICATION WILL LEAD
TO AN INCREASE CHANCE FOR ACTIVE CONVECTIVE WEATHER ACROSS CENTRAL
NC THIS PERIOD.
REST OF THE AFTERNOON AND TONIGHT... SCATTERED CONVECTION WILL
PERSIST THROUGH THIS AFTERNOON IN VICINITY OF A DIFFERENTIAL HEATING
BOUNDARY OVER THE SANDHILLS EXTENDING INTO THE EASTERN PIEDMONT. THE
SLY LOW LEVEL FLOW IS FEEDING MODERATELY UNSTABLE AIR MASS INTO THIS
BOUNDARY. THE INSTABILITY AXIS AT MID AFTERNOON EXTENDS FROM THE
TRIAD INTO THE SOUTHERN PIEDMONT...SO EXPECT THE SCATTERED STORMS TO
EVENTUALLY GENERATE/BUILD WESTWARD INTO THIS SECTION OF THE FORECAST
AREA BY LATE THIS AFTERNOON-EARLY EVENING. EFFECTIVE SHEAR
RELATIVELY WEAK IN THIS REGION SO ORGANIZED BANDS OF CONVECTION
APPEAR TO BE MINIMAL LATE THIS AFTERNOON/EARLY EVENING. STORMS WHICH
EXHIBIT SUSTAINED UPDRAFTS AND ASSOCIATED PRECIP LOADING WILL HAVE
THE THREAT TO PRODUCE LOCALLY STRONG/DAMAGING WIND GUSTS WHEN THE
PRECIP LOAD DESCENDS TO THE SURFACE. THIS THREAT APPEARS TO BE
HIGHEST OVER THE WESTERN AND SOUTHERN PIEDMONT WHICH HAS SEEN THE
MOST HEATING TODAY.
LATER TONIGHT (AFTER 02Z-4Z)...CONVECTIVE COMPLEX CURRENTLY CROSSING
SOUTHERN OH-NORTHERN KY WILL BE APPROACHING OUR NW COUNTIES.
MAJORITY OF WRF MODELS DISSIPATE THIS COMPLEX AS IT MOVES SEWD INTO
OUR REGION...THOUGH THE PAST FEW RUNS OF THE HRRR DRAGS THIS SYSTEM
(THOUGH IN SOMEWHAT WEAKER FORM) ACROSS THE REGION. GFS HAS HAD A
STRONG SIGNAL THE PAST FEW RUNS A WELL...BRING THIS SYSTEM THOUGH
OVERNIGHT. THUS...WILL MAINTAIN A HIGH END CHANCE OF CONVECTION
ACROSS MOST OF THE PIEDMONT.
EFFECTIVE BULK SHEAR EXPECTED TO INCREASE TO BETWEEN 20-30KTS WITH
MLCAPE 400-800J/KG. THIS SUGGEST A CHANCE FOR ORGANIZED CONVECTION
IN THE FORM OF BROKEN BANDS WITH SOME BOWING FEATURES POSSIBLE.
&&
.SHORT TERM /TUESDAY AND TUESDAY NIGHT/...
AS OF 335 PM MONDAY...
...RISK OF SEVERE THUNDERSTORMS WITH WIDESPREAD DAMAGING WINDS
PROBABLE TUESDAY NIGHT...
CONVECTIVE DEBRIS CLOUDINESS AND LINGERING SHOWERS OVER THE COASTAL
PLAIN WILL GRADUALLY MOVE OUT OR DIMINISH BY LATE MORNING. HEATING
OF THE MOIST AIR MASS WILL GENERATE A MODERATELY UNSTABLE ATMOSPHERE
BY AFTERNOON. A STEADY SW WIND AROUND 10KTS WITH GUSTS NEAR 20KTS
WILL PUSH AFTERNOON TEMPS WELL INTO THE 90S. NOT SEEING MUCH IN THE
MANNER OF A MECHANISM ALOFT TO TRIGGER ORGANIZED CONVECTION IN THE
AFTERNOON THOUGH PULSE TYPE THUNDERSTORMS A DEFINITE POSSIBILITY.
BULK SHEAR WILL BEGIN TO INCREASE LATE IN THE DAY...AND MORE SO
TUESDAY NIGHT AS A MID LEVEL 45-50KT ROUNDS THE BASE OF THE TROUGH.
THIS ENHANCED SHEAR WILL RESULT IN EFFECTIVE BULK SHEAR 30-40KTS. A
S/W RESPONSIBLE FOR CONVECTION EXPECTED TO FIRE OVER THE UPPER
MIDWEST THIS EVENING WILL INITIATE/SUSTAIN THIS CONVECTIVE COMPLEX
ACROSS CENTRAL NC. DUE TO THE STRONG HEATING EXPECTED TUESDAY
AFTERNOON...EXPECT DECENT LOW LEVEL LAPSE RATES TO PERSIST WELL INTO
THE EVENING HOURS. THE ENHANCED LOW LEVEL LAPSE RATES ALONG WITH THE
ABNORMALLY STRONG BULK SHEAR SUGGEST A GOOD PROBABILITY OF DAMAGING
WINDS WITH THE STRONGER/SEVERE STORMS. AN ISOLATED TORNADO OR TWO
CANNOT BE RULED OUT. THIS SEVERE WEATHER EPISODE MAY PERSIST WELL
INTO THE OVERNIGHT/PRE-DAWN HOURS.
&&
.LONG TERM /WEDNESDAY THROUGH MONDAY/...
AS OF 230 PM MONDAY...
THE UPPER TROUGH AXIS AND ASSOC SFC BOUNDARY ARE PROGGED TO MOVE
EAST OF I-95 BY 18Z WED...SO LOOK FOR PRECIP CHANCES TO WIND DOWN
DURING THE MORNING TO MID-DAY PERIOD WED. WITH THE AIRMASS CHANGE
LAGGING...HIGHS ON WED SHOULD STILL REACH THE LOW-MID 90S.
HIGH PRESSURE IN THE WAKE OF THE FRONT WILL BUILD INTO NC FOR THU
AND FRI...PROVIDING FAIR WEATHER AND COOLER TEMPS WITH READINGS NEAR
OR PERHAPS A FEW DEGREES BELOW NORMAL.
RAIN CHANCES WILL INCREASE BACK TO CLIMO AND PERHAPS ABOVE CLIMO
OVER THE WEEKEND INTO EARLY NEXT WEEK AS THE RIDGE CENTER OVER THE
LOWER MISS VALLEY MOVES WEST AND A SERIES OF SHORT WAVES ROUND THE
RIDGE TOP AND DROP SOUTHEAST ACROSS THE CAROLINAS. TEMPS DURING THIS
TIME WILL MODERATE BACK ABOVE NORMAL BY THE END OF THE WEEKEND AND
INTO MONDAY.
&&
.AVIATION /18Z MONDAY THROUGH SATURDAY/...
AS OF 125 PM MONDAY...
AN ACTIVE WEATHER PATTERN ACROSS THE EASTERN U.S. WILL RESULT IN
PERIODS OF CONVECTION ACROSS CENTRAL NC THROUGH WEDNESDAY AND
ASSOCIATED MVFR/IFR CONDITIONS DUE TO CEILINGS AND HEAVY RAIN
SHOWERS. ASIDE FROM THE CONVECTION...EXPECT VFR CONDITIONS.
THE HIGHEST THREAT FOR WIDESPREAD CONVECTION APPEARS TO BE TWOFOLD:
THE FIRST LATE THIS EVENING THROUGH THE OVERNIGHT HOURS...STARTING
AROUND 03Z IN THE TRIAD...SPREADING EAST BY 06Z. THE SECOND HIGHER
THAN NORMAL THREAT WILL BE TUESDAY NIGHT INTO WEDNESDAY MORNING.
OTHERWISE...EXPECT ISOLATED TO SCATTERED CONVECTION LATER THIS
AFTERNOON THROUGH EARLY EVENING. THIS IMMEDIATE CONVECTIVE THREAT
APPEARS HIGHEST OVER THE NORTHERN PIEDMONT...AND MAY AFFECT THE
TRIAD AND KRDU TERMINALS BETWEEN 21Z-01Z.
FOR THURSDAY THROUGH SATURDAY...EXPECT A RETURN TO A MORE TYPICAL
SUMMER PATTERN WITH EXTENDED PERIODS OF VFR CONDITIONS WITH ISOLATED
CONVECTION HIGHLY PROBABLE IN THE AFTERNOON-EARLY EVENING HOURS.
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...BLAES/CBL
NEAR TERM...WSS
SHORT TERM...WSS
LONG TERM...RAH
AVIATION...WSS
AREA FORECAST DISCUSSION
NWS MILWAUKEE/SULLIVAN WI
329 PM CDT MON JUL 13 2015
.SHORT TERM...
.TONIGHT... FORECAST CONFIDENCE MEDIUM.
INSTABILITY IS ON THE RISE IN SOUTH CENTRAL WI WITH MIXED LAYER CAPE
OVER 2500 J/KG AND NO CIN PER LATEST SPC MESOANALYSIS PAGE. THIS
AXIS OF INSTABILITY EXTENDS NORTHWESTWARD THROUGH EAST CENTRAL MN.
THUNDERSTORMS ARE POPPING UP IN THAT AREA AS OF 20Z AS A SHORTWAVE
WORKS INTO THE AREA. THE HRRR MODEL AND OTHER MESO MODELS HAVE BEEN
CONSISTENT IN DEVELOPING THUNDERSTORMS EAST CENTRAL/SOUTHEAST MN AND
THEY HAVE THE THUNDERSTORMS CONTINUING TO DEVELOP DOWNSTREAM WITH
THE SHORTWAVE. ALL OF SOUTHERN WI IS UNDER A SEVERE THUNDERSTORM
WATCH THROUGH 02Z OR 9 PM.
THE HIGH CAPE FORECAST OF 3500-4500 J/KG /DEPENDING ON MODEL/ AND
HIGH UNIDIRECTIONAL SHEAR AROUND 40 KNOTS SUPPORTS RAPID SUPERCELL
DEVELOPMENT. LARGE HAIL AND DAMAGING WINDS ARE LIKELY WITH THESE
STORMS. A TORNADO IS POSSIBLE.
STAY TUNED FOR UPDATES AND POTENTIAL SEVERE THUNDERSTORM WARNINGS.
AFTER THESE STORMS ROLL THROUGH... THERE IS A SMALL CHANCE FOR
ANOTHER ROUND OF WEAKER SHOWERS AND THUNDERSTORMS WITH ANOTHER
SHORTWAVE TRACKING THROUGH SOUTHERN WI LATE TONIGHT.
TUESDAY... FORECAST CONFIDENCE MEDIUM.
A COLD FRONT WILL SLIDE SOUTHWEST DOWN LAKE MICHIGAN THROUGH SOUTH
CENTRAL WI TUESDAY AFTERNOON IN THE WAKE OF AN UPPER LEVEL
SHORTWAVE. LOOK FOR A WIND SHIFT TO THE NORTH-NORTHEAST AND FALLING
TEMPERATURES. THERE MAY BE A LOW CLOUD DECK ALONG THE LEADING EDGE
OF THE FRONT. MODELS ARE SHOWING LOW CAPE AND LIGHT QPF... SO SOME
SHOWERS AND THUNDERSTORMS WILL BE POSSIBLE ALONG THE FRONT AS THEY
COLLIDE WITH THAT WARM AND MOIST AIR MASS IN PLACE.
.TUESDAY NIGHT AND WEDNESDAY...FORECAST CONFIDENCE MEDIUM
THE MID/UPPER LEVEL FLOW IS NORTHWEST AS A RIDGE EXITS THE DAKOTASAND
PUSHES INTO MINNESOTA. WEAK 700 MB DOWNWARD MOTION WITH MAINLY
WEAK UPPER CONVERGENCE UNTIL EVENING IN THE SOUTHWEST. 700 MB
DEWPOINTS ARE LOW...BUT BEGIN TO RISE WEDNESDAY AFTERNOON. 850 MB
TEMPERATURES COOL THROUGH THE PERIOD WITH THE 850 MB RIDGE OVER
WISCONSIN ON WEDNESDAY. 850 MB DEWPOINTS DROP THROUGH THE DAY
WEDNESDAY.
A BRISK NORTHEAST FLOW OFF LAKE MICHIGAN TUESDAY EVENING WITH
DIMINISH AS HIGH PRESSURE BUILDS INTO THE GREAT LAKES REGION.
DEWPOINTS ARE EXPECTED TO DROP INTO THE 40S AND LOWER 50S.
.WEDNESDAY NIGHT AND THURSDAY...FORECAST CONFIDENCE...MEDIUM.
THE UPPER RIDGE MOVES INTO WISCONSIN THURSDAY MORNING AS A
SHORTWAVE MOVES ACROSS THE NORTHERN/CENTRAL PLAINS. THE UPPER
DIVERGENCE INCREASES LATE WEDNESDAY NIGHT AND THURSDAY MORNING.
700 MB DEW POINTS CONTINUE TO INCREASE...ESPECIALLY OVER SOUTH
CENTRAL WISCONSIN. 700 MB UPWARD MOTION INCREASES...ESPECIALLY
THURSDAY.
AS THE SURFACE HIGH OVER THE GREAT LAKES RECEDES TO THE EAST...A
RETURN FLOW RESULTS IN A CHANCE OF THUNDERSTORMS
THURSDAY...ESPECIALLY OVER SOUTH CENTRAL WISCONSIN.
SURFACE DEWPOINTS ARE SLOW TO RISE INITIALLY BUT THEN INCREASES
INTO THE MID AND UPPER 60S OVER SOUTH CENTRAL WISCONSIN THURSDAY
AFTERNOON.
.LONG TERM...
.THURSDAY NIGHT AND FRIDAY...FORECAST CONFIDENCE MEDIUM
THE GFS AND 00Z ECMWF HAVE A FAIRLY ZONAL FLOW WITH ONE SHORTWAVE
EXITING WISCONSIN THURSDAY NIGHT AS A STRONG TROUGH DROPS INTO
THE NORTHWEST U.S.
A SURFACE TROUGH MOVES ACROSS WISCONSIN THURSDAY NIGHT AND OFF TO
LOWER MICHIGAN FRIDAY WITH AN AREA OF SHOWERS AND THUNDERSTORMS.
.SATURDAY...FORECAST CONFIDENCE MEDIUM
THE 00Z ECMWF PUSHES A MID LEVEL TROUGH INTO THE NORTHERN ROCKIES
AND NORTHERN PLAINS...WHILE THE GFS HAS A MORE CLOSED LOW OVER THE
PACIFIC NORTHWEST...WITH A SHORTWAVE MOVING TOWARD SOUTH CENTRAL
CANADA.
A SURFACE TROUGH DEVELOPS IN THE PLAINS WITH A WEAK SOUTH TO
SOUTHEAST FLOW OVER SOUTHERN WISCONSIN.
.SUNDAY AND MONDAY...FORECAST CONFIDENCE LOW
THE 00Z ECMWF MOVES A RATHER STRONG SHORTWAVE INTO
MINNESOTA SUNDAY AND INTO WISCONSIN MONDAY. HOWEVER THE 12Z GFS
STILL HAS A TROUGH OVER THE WESTERN U.S. SUNDAY THEN FINALLY
KICKING OUT A SHORTWAVE INTO THE NORTHERN PLAINS MONDAY
AFTERNOON.
BOTH MODELS SHOW SHOWER AND THUNDERSTORM CHANCES.
&&
.AVIATION/00Z TAFS/...
AREA OF DIURNAL CU WITH BASES AROUND 2000 FEET ARE SPREADING INTO
SOUTH CENTRAL WI THIS AFTERNOON WITH INCREASING DEWPOINT TEMPS AND
WSW WINDS. SCATTERED THUNDERSTORMS DEVELOPING IN SOUTHEAST MN NOW
WILL CONTINUE TO DEVELOP DOWNSTREAM IN WEST CENTRAL WI AND
EVENTUALLY SOUTH CENTRAL AND SOUTHEAST WI LATER THIS AFTERNOON AND
INTO THE EVENING. SOME STORMS COULD BE SEVERE. BRIEF MVFR CONDITIONS
AND GUSTY WINDS AND HAIL ARE POSSIBLE IN THESE THUNDERSTORMS.
THERE IS A CHANCE FOR WEAKER SHOWERS AND THUNDERSTORMS ACROSS
SOUTHERN WI LATER TONIGHT. A BRIEF PERIOD OF MVFR CIGS AND MAYBE
SOME SHOWERS/THUNDER WILL BE POSSIBLE WITH A COLD FRONT TRACKING
FROM NORTHERN LAKE MICHIGAN SOUTHWEST THROUGH SOUTHERN WI TUESDAY
AFTERNOON.
&&
.MKX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
LM...NONE.
&&
$$
TONIGHT/TUESDAY AND AVIATION/MARINE...MRC
TUESDAY NIGHT THROUGH MONDAY...HENTZ