Forecast Discussions mentioning any of
"HRRR" "RAP" "RR" "RUC13" "RUC" received at GSD on 06/22/13
AREA FORECAST DISCUSSION
NWS DENVER/BOULDER CO
826 PM MDT FRI JUN 21 2013
.UPDATE...
&&
.SHORT TERM...ONE OUTFLOW BNDRY HAS MOVED INTO THE URBAN CORRIDOR
BUT NO CONVECTION HAS DEVELOPED SO FAR AS AIRMASS APPEARS CAPPED
ALTHOUGH A FEW STORMS HAVE FIRED OVER SERN WY. FOR NOW WILL KEEP
ISOLD STORMS THRU MIDNIGHT ALONG AND NEAR THE WY-NE BORDER.
MEANWHILE ANOTHER STRONGER OUTFLOW BNDRY IS MOVING SOUTH ACROSS
ECNTRL WY INTO THE NE PANHANDLE AND WILL MOVE INTO NERN CO LATER
TONIGHT WITH AN INCREASE IN MOISTURE WHICH MAY LEAD TO SOME
STRATUS OVER THE NERN PLAINS AFTER 12Z.
.AVIATION...FIRST OUTFLOW BNDRY HAS MOVED THRU HOWEVER A 2ND
STRONGER ONE IS MOVING SOUTH FM WY AND NE AND MAY AFFECT THE AREA
LATER TONIGHT. LATEST RAP SHOWS STRATUS DEVELOPING BEHIND THIS
BNDRY OVER THE NERN PLAINS BY 12Z WITH IT GETTING CLOSE TO THE
AIRPORT IN THE 13Z-15Z PERIOD. FOR NOW WILL NOT MENTION IT BUT WILL
NEED TO BE WATCHED.
&&
.PREV DISCUSSION... /ISSUED 734 PM MDT FRI JUN 21 2013/
UPDATE...
AVIATION...OUTFLOW BNDRY FROM CONVECTION OVER THE NERN PLAINS
WILL REACH THE AIRPORT BY 0145Z WITH A BRIEF PERIOD OF GUSTY NE
WINDS UP TO 25 MPH. BY 03Z WINDS MAY BECOME MORE ELY WITH SPEEDS
IN THE 10-15 MPH RANGE AND THEN SHIFT TO SELY BY 05Z.
PREV DISCUSSION... /ISSUED 353 PM MDT FRI JUN 21 2013/
SHORT TERM...UPPER AIR PATTERN WITH MODERATE SOUTHWESTERLY FLOW
ALOFT WILL REMAIN LOCKED OVER COLORADO THROUGH SATURDAY. MORE
WARM TEMPERATURES AND GENERALLY DRY CONDITIONS ARE EXPECTED OVER
THE MOUNTAINS AND ADJACENT PLAINS. SOUTHWESTERLY WINDS GUSTING UP
TO 25-30 MPH ARE EXPECTED IN MOUNTAIN AREAS AGAIN IN THE
AFTERNOON. RELATIVE HUMIDITIES WILL HAVE POOR RECOVERY OVERNIGHT
IN THE MOUNTAINS AND THEN FALL TO AROUND 10 PERCENT AGAIN TOMORROW
AFTERNOON. SEE FIRE WEATHER SECTION BELOW.
ACROSS THE PLAINS...HIGHS COULD BE A COUPLE DEGREES COOLER THAN
THIS AFTERNOON...BUT SHOULD STILL REACH THE LOWER 90S. THE FAR
NORTHEAST PLAINS WILL ONCE AGAIN SEE LOW LEVEL MOISTURE MOVE IN
FROM THE NORTHEAST AND THEN LINGER TOMORROW AFTERNOON TO SUPPORT
SCATTERED THUNDERSTORM ACTIVITY...SIMILAR TO THE SITUATION IN
PLACE THIS AFTERNOON. CLOSER TO THE FOOTHILLS...LOW LEVEL MOISTURE
LEVELS WILL BE HIGH IN THE MORNING...BUT SHOULD THEN FLUSH OUT IN
THE EARLY AFTERNOON AS DRIER SOUTHWESTERLY FLOW MIXES TO THE
SURFACE. A FEW SHOWERS WILL AGAIN BE POSSIBLE OVER THE
MOUNTAINS...BUT GUSTY WINDS AND ONLY LIGHT RAIN SHOULD RESULT.
LONG TERM...A FEW STORMS WILL BE POSSIBLE ACROSS THE FAR NORTHEAST
CORNER EARLY IN THE EVENING WHERE THERE THERE WILL BE LOCAL
SURFACE CONVERGENCE AND SOME LOW LEVEL MOISTURE. A FEW STORMS
COULD PRODUCE BRIEF MODERATE RAINFALL. ANY SEVERE THREAT SHOULD BE
NORTHEAST OF THE AREA. OTHERWISE...PARTLY CLOUDY SKIES WILL
PREVAIL. ON SUNDAY... SOUTHWEST FLOW ALOFT WILL CONTINUE. MODELS
CONTINUE TO BRING A COLD FRONT ACROSS THE PLAINS DURING THE
MORNING WITH COOLER AIR AND AN INCREASE IN LOW LEVEL MOISTURE. NAM
INDICATING MORE LOW LEVEL THAN THE OTHER MODELS...WITH THE GFS THE
DRIEST. IN ANY CASE...IT APPEARS THERE WILL BE SOME CHANCE FOR
AFTERNOON STORMS ACROSS THE PLAINS FROM ROUGHLY INTERSTATE 70
NORTHWARD. STILL A BIT UNSURE ABOUT THE CHANCES FURTHER SOUTH AND
OPT NOT TO INCLUDE STORMS AT THIS POINT. A FEW STORMS COULD
PRODUCE BRIEF MODERATE RAINFALL. ACROSS FOOTHILLS...MODELS DO SHOW
THE EASTERLY PUSH GETTING INTO THE LOWER SECTIONS. WILL CONTINUE
THE SLIGHT CHANCE OF STORMS FOR ZONE 35 WHERE THERE WILL BE BETTER
LOW LEVEL MOISTURE AND UPSLOPE. AS FOR MOUNTAINS...CROSS SECTIONS
INDICATE SOME MID LEVEL MOISTURE OVER THE AREA DURING THE
AFTERNOON...A FEW HIGH BASED STORMS COULD DEVELOP LATE IN THE DAY
ACROSS THE HIGHER RIDGES. SOME STORMS WILL BE POSSIBLE DURING THE
EVENING ACROSS THE NORTHEAST CORNER WITH PERHAPS A FEW STORMS
ACROSS THE HIGHER MOUNTAINS. OTHERWISE...SKIES WILL GRADUALLY
CLEAR. ON MONDAY...FLOW ALOFT BECOMES A BIT MORE WESTERLY AS AN
UPPER TROUGH MOVES ACROSS IDAHO AND WESTERN MONTANA. MODELS SHOW
SOME LOW LEVEL MOISTURE OVER THE NORTHEAST CORNER WITH MAINLY DRY
CONDITONS ELSEWHERE. WILL KEEP STORMS OUT OF THE FORECAST FOR NOW.
FOR TUESDAY...FLOW ALOFT BECOMES WESTERLY AS MODELS SHOW UPPER
TROUGH MOVING ACROSS MONTANA. SURFACE LEE TROUGH DEVELOPS ACROSS
THE PLAINS WHICH SHOULD HELP INCREASE THE DOWNSLOPE FLOW. AIRMASS
LOOKING DRY AND WARM...WITH PERHAPS BREEZY CONDITIONS. FIRE DANGER
TO REMAIN ELEVATED.
FOR THE LATER DAYS WEDNESDAY THROUGH FRIDAY...MODELS SHOW UPPER
RIDGE OVER THE AREA THROUGH THE PERIOD WITH A WEAKER GRADIENT
ALONG WITH WARM AND MAINLY DRY AIRMASS. MODELS INDICATE SOME MID
LEVEL MOISTURE MOVING ACROSS THE MOUNTAINS FRIDAY. WILL INCLUDE A
SLIGHT CHANCE OF THUNDERSTORMS FOR THE MOUNTAINS AND FOOTHILLS.
WILL KEEP THE PLAINS DRY.
AVIATION...NO MAJOR AVIATION IMPACTS. WINDS WILL OSCILLATE BACK
AND FORTH BETWEEN SOUTHWEST AND SOUTHEAST THROUGH TONIGHT AND
TOMORROW. SMOKE PLUMES FROM FIRES OVER SOUTHERN COLORADO SHOULD
STAY ELEVATED AS THEY MOVE ACROSS THE DENVER METRO AREA.
FIRE WEATHER...LOOKS LIKE CONDITIONS TOMORROW WILL BE VERY
SIMILAR TO TODAY. LOW HUMIDITIES ARE EXPECTED AGAIN ALONG WITH
AFTERNOON WINDS THAT WILL APPROACH RED FLAG CRITERIA. WILL ISSUE
ANOTHER RED FLAG WARNING FOR SATURDAY AFTERNOON AND EVENING IN THE
MOUNTAIN PARKS AND ALONG THE PALMER DIVIDE. MOUNTAIN ZONES STILL
HAVE ENOUGH SNOWPACK TO KEEP FUEL MOISTURES HIGHER IN THOSE ZONES.
WE WILL CONTINUE TO KEEP AN EYE ON BEHAVIOR OF THE LIME GULCH FIRE
AS A BAROMETER OF AMBIENT FIRE CONDITIONS IN THE FOOTHILLS. SO
FAR...BEHAVIOR IN OUR FORECAST AREA HAS BEEN NOWHERE AS VOLATILE
AS IN THE SAN JUAN MOUNTAINS AND SANGRE DE CRISTO AREAS TO OUR
SOUTH.
HYDROLOGY...NO CONCERNS.
&&
.BOU WATCHES/WARNINGS/ADVISORIES...
RED FLAG WARNING FROM NOON TO 8 PM MDT SATURDAY FOR COZ211-213-
214-241.
&&
$$
SHORT TERM...RPK
LONG TERM....D-L
AVIATION...RPK
AREA FORECAST DISCUSSION
NWS PUEBLO CO
1117 AM MDT THU JUN 20 2013
.UPDATE...
ISSUED AT 1011 AM MDT THU JUN 20 2013
BASED ON CURRENT CONDITIONS ACROSS THE REGION...THE RED FLAG WARNING HAS
BEEN CHANGED TO BEGIN NOW INSTEAD OF 11 AM. WINDS HAVE PICKED UP
EARLY ACROSS MOST OF THE WARNING AREA...WITH GUSTS TO 27KTS AT
TRINIDAD AND MONARCH PASS WITH RH LEVELS FALLING RAPIDLY. -PJC
UPDATE ISSUED AT 919 AM MDT THU JUN 20 2013
UPDATED THE GRIDS TO MATCH CURRENT TEMPERATURE AND WIND TRENDS AND
UPDATED ALL FIRE WEATHER PRODUCTS. -PJC
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 401 AM MDT THU JUN 20 2013
...CRITICAL FIRE WEATHER CONDITIONS EXPECTED AGAIN TODAY...
CURRENT WATER VAPOR IMAGERY AND UPPER AIR ANALYSIS INDICATING
MODERATE SOUTHWEST FLOW ALOFT ACROSS THE STATE WITH UPPER LEVEL
RIDGING IN PLACE ACROSS THE HIGH PLAINS ALONG WITH AN UPPER LOW
SPINNING ACROSS THE PACIFIC NORTHWEST AT THIS TIME. WATER VAPOR
IMAGERY ALSO INDICATING AN EMBEDDED SHORT WAVE LIFTING OUT ACROSS
EASTERN UTAH WITH ANOTHER WAVE TRANSLATING ACROSS CENTRAL NEVADA AT
THIS TIME. MSAS DATA AND CURRENT OBS INDICATING LEE TROUGHING ACROSS
THE I-25 CORRIDOR WITH LOWERING PRESSURES ACROSS THE EASTERN PLAINS
AT THIS TIME. SHALLOW LOW LEVEL MOISTURE HAS MADE IT BACK ACROSS THE
I-25 CORRIDOR WITH DEW PTS IN THE 40S AND 50S ACROSS THE EASTERN
PLAINS...THOUGH HIGHER ELEVATION DEW PTS ARE IN THE SINGLE DIGITS
AND TEENS AT THIS TIME. 3.9U IR SATELLITE IMAGERY CONTINUES TO
INDICATE A HOT SPOT SOUTHEAST OF LA VETA PASS ASSOCIATED WITH THE
EAST PEAK/SCOUT RANCH FIRE ALONG WITH ANOTHER HOT SPOT NORTHWEST OF
WOLF CREEK PASS ASSOCIATED WITH THE WEST FORK COMPLEX FIRE.
SATELLITE DATA ALSO INDICATING SMOKE ACROSS THE SAN LUIS VALLEY
THROUGH THE WET MT VALLEY AND INTO PUEBLO AND EL PASO COUNTIES AT
THIS TIME.
TODAY AND TONIGHT...NO BIG CHANGES TO CURRENT FORECAST WITH CONTINUED
MODERATE SOUTHWEST FLOW ALOFT ACROSS THE STATE AS EASTERN UTAH SHORT
WAVE CONTINUES TO TRANSLATE ACROSS THE NORTHERN ROCKIES. THIS WILL
ALLOW LEE TROUGH TO CONTINUE TO PUSH OUT ACROSS THE FAR SE PLAINS
WITH DRY AND BREEZY SOUTHWEST WINDS OF 15 TO 30 MPH MIXING DOWN
ACROSS THE ALL OF SOUTH CENTRAL AND SOUTHEAST COLORADO LATE THIS
MORNING THROUGH THE EARLY EVENING. CURRENT FORECAST USED A BLEND OF
DEW PTS FROM THE HIGHER RES RUC AND HRRR ALONG WITH LOCAL WRF WITH
MIN RHS OF 5-15 PERCENT EXPECTED ACROSS THE AREA TODAY. THIS ALONG
WITH BREEZY WINDS AND RESULTANT WARM TEMPS WILL CREATE CRITICAL FIRE
WEATHER CONDITIONS ACROSS THE AREA AGAIN TODAY...WITH CURRENT RED
FLAG WARNING FOR THE I-25 CORRIDOR WESTWARD REMAINING IN TACT FROM
11AM TO 8PM. FURTHER EAST...RECENT RAINS HAVE HELPED TO TEMPER FIRE
DANGER A TAD WITH AREA LAND MANAGEMENT AGENCIES INDICATING NON
CRITICAL FUELS AT THIS TIME. SOUTHWEST FLOW ALOFT ALONG WITH
EXPECTED PLUMING OF CURRENT ACTIVE FIRES ACROSS THE CWA (EAST
PEAK...WEST FORK...AND BULL GULCH) EXPECTING TO SEE AREAS OF SMOKE
AFFECTING MUCH OF SOUTH CENTRAL AND SOUTHEAST COLORADO TODAY.
NAM CONTINUES TO BE A TAD SLOWER WITH MIXING OUT LOW LEVEL MOISTURE
ACROSS THE FAR SE PLAINS AND TRIES TO DEVELOP A FEW STORMS THIS
AFTERNOON NEAR THE OKLAHOMA AND SW KANSAS BORDERS. HIGHER RES MODELS
KEEP CONVECTION FURTHER EAST...THOUGH HAVE KEPT SILENT POPS ACROSS
THIS AREA AT THIS TIME. MODERATE SW FLOW ALOFT CONTINUES ACROSS THE
AREA TONIGHT AS NEVADA SHORT WAVE CONTINUES TO TRANSLATE NORTH AND
EAST...WITH LEE TROUGHING RE ESTABLISHING ACROSS THE I-25 CORRIDOR
OVERNIGHT. LOW LEVEL MOISTURE MOVES BACK ACROSS THE EASTERN PLAINS
AND TRIES TO MAKE IT INTO THE I-25 CORRIDOR WITH SOUTH TO SOUTHEAST
WINDS. NOT SURE HOW FAR WEST THE MOISTURE WILL MAKE IT BACK...THOUGH
WILL CONTINUE TO BE SHALLOW WITH HIGHER ELEVATIONS AND CURRENT FIRES
HAVING POOR RH RECOVERY ONCE AGAIN TONIGHT.
.LONG TERM...(FRIDAY THROUGH WEDNESDAY)
ISSUED AT 401 AM MDT THU JUN 20 2013
...HOT AND DRY WITH CRITICAL FIRE WEATHER CONDITIONS THROUGH
SATURDAY...
HOT...DRY AND BREEZY/WINDY CONDITIONS ARE EXPECTED OVER THE FORECAST
AREA THROUGH AT LEAST SATURDAY AS SOUTHWESTERLY FLOW REMAINS OVER
THE REGION. THIS SOUTHWESTERLY FLOW IS ASSOCIATED WITH A TROUGH THAT
HAS BEEN OVER THE NORTHWEST CONUS FOR THE LAST FEW DAYS. A FIRE
WEATHER WATCH IS IN EFFECT FOR FRIDAY AND I EXPECT THIS WILL BE
UPGRADED TO A WARNING LATER TODAY. ADDITIONALLY...I ANTICIPATE A NEW
FIRE WEATHER WATCH WILL BE ISSUED FOR SATURDAY FOR THE SAME REGION.
THESE WATCHES MAY NEED TO BE EXPANDED FARTHER EAST AS RH VALUES ARE
EXPECTED TO REACH CRITICAL VALUES OVER MOST OF THE EASTERN PLAINS
FRIDAY AND SATURDAY.
FOR SUNDAY AND MONDAY...THE TROUGH TO OUR NORTHWEST WILL REMAIN BUT
THE GRADIENT WILL SLACKEN A BIT AND THIS WILL ALLOW FOR LESS
WIND...AND FIRE WEATHER CONDITIONS WILL NOT BE AS CRITICAL. IT WILL
STILL BE HOT AND DRY.
INTO NEXT WEEK...FLOW BECOMES ZONAL WITH THE JET LIFTING NORTH.
WINDS WILL MAINLY BE DIURNALLY DRIVEN BUT IT IS EXPECTED TO REMAIN
DRY AND ON THE WARM SIDE.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z FRIDAY AFTERNOON)
ISSUED AT 1111 AM MDT THU JUN 20 2013
THOUGH VFR CONDITIONS ARE LIKELY...AT KALS...KCOS...AND KPUB
THROUGH 18Z TOMORROW...OCCASIONAL MVFR CONDITIONS ARE POSSIBLE DUE
TO SMOKE FROM NUMEROUS WILD FIRES ACROSS SOUTHEAST COLORADO.
THE OTHER CONCERN IS GUSTY SOUTH AND SOUTHWEST WINDS OF
15-30KTS...WITH OCCASIONAL GUSTS TO 35KTS THIS AFTERNOON AT ALL 3
SITES. -PJC
&&
.FIRE WEATHER...
ISSUED AT 401 AM MDT THU JUN 20 2013
PLEASE SEE SHORT TERM DISCUSSION FOR FIRE WEATHER CONCERNS FOR
TODAY AND TONIGHT.
LONG TERM FIRE WEATHER CONCERNS...
METEOROLOGICAL CONDITIONS FOR EXTREME FIRE BEHAVIOR WILL OCCUR
OVER THE DISTRICT FRIDAY AT SATURDAY. WINDS OVER THE VALLEYS AND
MTNS WILL GENERA LY RANGE BETWEEN 15 TO 20 MPH WITH GUSTS TO 30
TO 35 MPH.
OVER THE I-25 CORRIDOR...CONDITIONS WILL BE CRITICAL FOR THE MOST
PART. THAT PART OF PUEBLO COUNTY WHICH IS DIRECTLY IN THE LEE OF THE
WET MTNS MAY SEE WINDS BELOW 25 MPH BOTH FRIDAY AND SATURDAY.
FARTHER EAST...IT IS EXPECTED TO DRY OUT FRIDAY AND SATURDAY AS THE
LOW LVL MOISTURE WHICH HAS BEEN OVER THE REGION IS PUSHED WELL INTO
KS. THESE AREAS MAY BE ADDED TO THE FIRE WX HILITES WHICH ARE IN
PLACE FOR THE AREA FOR FRIDAY.
&&
.PUB WATCHES/WARNINGS/ADVISORIES...
RED FLAG WARNING UNTIL 8 PM MDT THIS EVENING FOR COZ220>230.
FIRE WEATHER WATCH FROM FRIDAY MORNING THROUGH FRIDAY EVENING
FOR COZ220>230.
&&
$$
UPDATE...PJC
SHORT TERM...MW
LONG TERM...HODANISH
AVIATION...PJC
FIRE WEATHER...HODANISH
AREA FORECAST DISCUSSION
NWS PUEBLO CO
1014 AM MDT THU JUN 20 2013
.UPDATE...
ISSUED AT 1011 AM MDT THU JUN 20 2013
BASED ON CURRENT CONDITIONS ACROSS THE REGION...THE RED FLAG WARNING HAS
BEEN CHANGED TO BEGIN NOW INSTEAD OF 11 AM. WINDS HAVE PICKED UP
EARLY ACROSS MOST OF THE WARNING AREA...WITH GUSTS TO 27KTS AT
TRINIDAD AND MONARCH PASS WITH RH LEVELS FALLING RAPIDLY. -PJC
UPDATE ISSUED AT 919 AM MDT THU JUN 20 2013
UPDATED THE GRIDS TO MATCH CURRENT TEMPERATURE AND WIND TRENDS AND
UPDATED ALL FIRE WEATHER PRODUCTS. -PJC
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 401 AM MDT THU JUN 20 2013
...CRITICAL FIRE WEATHER CONDITIONS EXPECTED AGAIN TODAY...
CURRENT WATER VAPOR IMAGERY AND UPPER AIR ANALYSIS INDICATING
MODERATE SOUTHWEST FLOW ALOFT ACROSS THE STATE WITH UPPER LEVEL
RIDGING IN PLACE ACROSS THE HIGH PLAINS ALONG WITH AN UPPER LOW
SPINNING ACROSS THE PACIFIC NORTHWEST AT THIS TIME. WATER VAPOR
IMAGERY ALSO INDICATING AN EMBEDDED SHORT WAVE LIFTING OUT ACROSS
EASTERN UTAH WITH ANOTHER WAVE TRANSLATING ACROSS CENTRAL NEVADA AT
THIS TIME. MSAS DATA AND CURRENT OBS INDICATING LEE TROUGHING ACROSS
THE I-25 CORRIDOR WITH LOWERING PRESSURES ACROSS THE EASTERN PLAINS
AT THIS TIME. SHALLOW LOW LEVEL MOISTURE HAS MADE IT BACK ACROSS THE
I-25 CORRIDOR WITH DEW PTS IN THE 40S AND 50S ACROSS THE EASTERN
PLAINS...THOUGH HIGHER ELEVATION DEW PTS ARE IN THE SINGLE DIGITS
AND TEENS AT THIS TIME. 3.9U IR SATELLITE IMAGERY CONTINUES TO
INDICATE A HOT SPOT SOUTHEAST OF LA VETA PASS ASSOCIATED WITH THE
EAST PEAK/SCOUT RANCH FIRE ALONG WITH ANOTHER HOT SPOT NORTHWEST OF
WOLF CREEK PASS ASSOCIATED WITH THE WEST FORK COMPLEX FIRE.
SATELLITE DATA ALSO INDICATING SMOKE ACROSS THE SAN LUIS VALLEY
THROUGH THE WET MT VALLEY AND INTO PUEBLO AND EL PASO COUNTIES AT
THIS TIME.
TODAY AND TONIGHT...NO BIG CHANGES TO CURRENT FORECAST WITH CONTINUED
MODERATE SOUTHWEST FLOW ALOFT ACROSS THE STATE AS EASTERN UTAH SHORT
WAVE CONTINUES TO TRANSLATE ACROSS THE NORTHERN ROCKIES. THIS WILL
ALLOW LEE TROUGH TO CONTINUE TO PUSH OUT ACROSS THE FAR SE PLAINS
WITH DRY AND BREEZY SOUTHWEST WINDS OF 15 TO 30 MPH MIXING DOWN
ACROSS THE ALL OF SOUTH CENTRAL AND SOUTHEAST COLORADO LATE THIS
MORNING THROUGH THE EARLY EVENING. CURRENT FORECAST USED A BLEND OF
DEW PTS FROM THE HIGHER RES RUC AND HRRR ALONG WITH LOCAL WRF WITH
MIN RHS OF 5-15 PERCENT EXPECTED ACROSS THE AREA TODAY. THIS ALONG
WITH BREEZY WINDS AND RESULTANT WARM TEMPS WILL CREATE CRITICAL FIRE
WEATHER CONDITIONS ACROSS THE AREA AGAIN TODAY...WITH CURRENT RED
FLAG WARNING FOR THE I-25 CORRIDOR WESTWARD REMAINING IN TACT FROM
11AM TO 8PM. FURTHER EAST...RECENT RAINS HAVE HELPED TO TEMPER FIRE
DANGER A TAD WITH AREA LAND MANAGEMENT AGENCIES INDICATING NON
CRITICAL FUELS AT THIS TIME. SOUTHWEST FLOW ALOFT ALONG WITH
EXPECTED PLUMING OF CURRENT ACTIVE FIRES ACROSS THE CWA (EAST
PEAK...WEST FORK...AND BULL GULCH) EXPECTING TO SEE AREAS OF SMOKE
AFFECTING MUCH OF SOUTH CENTRAL AND SOUTHEAST COLORADO TODAY.
NAM CONTINUES TO BE A TAD SLOWER WITH MIXING OUT LOW LEVEL MOISTURE
ACROSS THE FAR SE PLAINS AND TRIES TO DEVELOP A FEW STORMS THIS
AFTERNOON NEAR THE OKLAHOMA AND SW KANSAS BORDERS. HIGHER RES MODELS
KEEP CONVECTION FURTHER EAST...THOUGH HAVE KEPT SILENT POPS ACROSS
THIS AREA AT THIS TIME. MODERATE SW FLOW ALOFT CONTINUES ACROSS THE
AREA TONIGHT AS NEVADA SHORT WAVE CONTINUES TO TRANSLATE NORTH AND
EAST...WITH LEE TROUGHING RE ESTABLISHING ACROSS THE I-25 CORRIDOR
OVERNIGHT. LOW LEVEL MOISTURE MOVES BACK ACROSS THE EASTERN PLAINS
AND TRIES TO MAKE IT INTO THE I-25 CORRIDOR WITH SOUTH TO SOUTHEAST
WINDS. NOT SURE HOW FAR WEST THE MOISTURE WILL MAKE IT BACK...THOUGH
WILL CONTINUE TO BE SHALLOW WITH HIGHER ELEVATIONS AND CURRENT FIRES
HAVING POOR RH RECOVERY ONCE AGAIN TONIGHT.
.LONG TERM...(FRIDAY THROUGH WEDNESDAY)
ISSUED AT 401 AM MDT THU JUN 20 2013
...HOT AND DRY WITH CRITICAL FIRE WEATHER CONDITIONS THROUGH
SATURDAY...
HOT...DRY AND BREEZY/WINDY CONDITIONS ARE EXPECTED OVER THE FORECAST
AREA THROUGH AT LEAST SATURDAY AS SOUTHWESTERLY FLOW REMAINS OVER
THE REGION. THIS SOUTHWESTERLY FLOW IS ASSOCIATED WITH A TROUGH THAT
HAS BEEN OVER THE NORTHWEST CONUS FOR THE LAST FEW DAYS. A FIRE
WEATHER WATCH IS IN EFFECT FOR FRIDAY AND I EXPECT THIS WILL BE
UPGRADED TO A WARNING LATER TODAY. ADDITIONALLY...I ANTICIPATE A NEW
FIRE WEATHER WATCH WILL BE ISSUED FOR SATURDAY FOR THE SAME REGION.
THESE WATCHES MAY NEED TO BE EXPANDED FARTHER EAST AS RH VALUES ARE
EXPECTED TO REACH CRITICAL VALUES OVER MOST OF THE EASTERN PLAINS
FRIDAY AND SATURDAY.
FOR SUNDAY AND MONDAY...THE TROUGH TO OUR NORTHWEST WILL REMAIN BUT
THE GRADIENT WILL SLACKEN A BIT AND THIS WILL ALLOW FOR LESS
WIND...AND FIRE WEATHER CONDITIONS WILL NOT BE AS CRITICAL. IT WILL
STILL BE HOT AND DRY.
INTO NEXT WEEK...FLOW BECOMES ZONAL WITH THE JET LIFTING NORTH.
WINDS WILL MAINLY BE DIURNALLY DRIVEN BUT IT IS EXPECTED TO REMAIN
DRY AND ON THE WARM SIDE.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z FRIDAY MORNING)
ISSUED AT 401 AM MDT THU JUN 20 2013
MAINLY VFR CONDITIONS ARE EXPECTED AT KALS...KCOS...AND KPUB FOR THE
NEXT 24 HOURS...THOUGH PERIODS OF MVFR WILL BE POSSIBLE DUE TO SMOKE
FROM CURRENT WILD FIRES ACROSS THE STATE. GUSTY SOUTH TO SOUTHWEST
WINDS OF 15-30KTS EXPECTED TO DEVELOP THROUGH THE LATE MORNING AND
PERSIST THROUGH THE EARLY EVENING.
&&
.FIRE WEATHER...
ISSUED AT 401 AM MDT THU JUN 20 2013
PLEASE SEE SHORT TERM DISCUSSION FOR FIRE WEATHER CONCERNS FOR
TODAY AND TONIGHT.
LONG TERM FIRE WEATHER CONCERNS...
METEOROLOGICAL CONDITIONS FOR EXTREME FIRE BEHAVIOR WILL OCCUR
OVER THE DISTRICT FRIDAY AT SATURDAY. WINDS OVER THE VALLEYS AND
MTNS WILL GENERA LY RANGE BETWEEN 15 TO 20 MPH WITH GUSTS TO 30
TO 35 MPH.
OVER THE I-25 CORRIDOR...CONDITIONS WILL BE CRITICAL FOR THE MOST
PART. THAT PART OF PUEBLO COUNTY WHICH IS DIRECTLY IN THE LEE OF THE
WET MTNS MAY SEE WINDS BELOW 25 MPH BOTH FRIDAY AND SATURDAY.
FARTHER EAST...IT IS EXPECTED TO DRY OUT FRIDAY AND SATURDAY AS THE
LOW LVL MOISTURE WHICH HAS BEEN OVER THE REGION IS PUSHED WELL INTO
KS. THESE AREAS MAY BE ADDED TO THE FIRE WX HILITES WHICH ARE IN
PLACE FOR THE AREA FOR FRIDAY.
&&
.PUB WATCHES/WARNINGS/ADVISORIES...
RED FLAG WARNING UNTIL 8 PM MDT THIS EVENING FOR COZ220>230.
FIRE WEATHER WATCH FROM FRIDAY MORNING THROUGH FRIDAY EVENING
FOR COZ220>230.
&&
$$
UPDATE...PJC
SHORT TERM...MW
LONG TERM...HODANISH
AVIATION...MW
FIRE WEATHER...HODANISH
AREA FORECAST DISCUSSION
NWS PUEBLO CO
924 AM MDT THU JUN 20 2013
.UPDATE...
ISSUED AT 919 AM MDT THU JUN 20 2013
UPDATED THE GRIDS TO MATCH CURRENT TEMPERATURE AND WIND TRENDS AND
UPDATED ALL FIRE WEATHER PRODUCTS. -PJC
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 401 AM MDT THU JUN 20 2013
...CRITICAL FIRE WEATHER CONDITIONS EXPECTED AGAIN TODAY...
CURRENT WATER VAPOR IMAGERY AND UPPER AIR ANALYSIS INDICATING
MODERATE SOUTHWEST FLOW ALOFT ACROSS THE STATE WITH UPPER LEVEL
RIDGING IN PLACE ACROSS THE HIGH PLAINS ALONG WITH AN UPPER LOW
SPINNING ACROSS THE PACIFIC NORTHWEST AT THIS TIME. WATER VAPOR
IMAGERY ALSO INDICATING AN EMBEDDED SHORT WAVE LIFTING OUT ACROSS
EASTERN UTAH WITH ANOTHER WAVE TRANSLATING ACROSS CENTRAL NEVADA AT
THIS TIME. MSAS DATA AND CURRENT OBS INDICATING LEE TROUGHING ACROSS
THE I-25 CORRIDOR WITH LOWERING PRESSURES ACROSS THE EASTERN PLAINS
AT THIS TIME. SHALLOW LOW LEVEL MOISTURE HAS MADE IT BACK ACROSS THE
I-25 CORRIDOR WITH DEW PTS IN THE 40S AND 50S ACROSS THE EASTERN
PLAINS...THOUGH HIGHER ELEVATION DEW PTS ARE IN THE SINGLE DIGITS
AND TEENS AT THIS TIME. 3.9U IR SATELLITE IMAGERY CONTINUES TO
INDICATE A HOT SPOT SOUTHEAST OF LA VETA PASS ASSOCIATED WITH THE
EAST PEAK/SCOUT RANCH FIRE ALONG WITH ANOTHER HOT SPOT NORTHWEST OF
WOLF CREEK PASS ASSOCIATED WITH THE WEST FORK COMPLEX FIRE.
SATELLITE DATA ALSO INDICATING SMOKE ACROSS THE SAN LUIS VALLEY
THROUGH THE WET MT VALLEY AND INTO PUEBLO AND EL PASO COUNTIES AT
THIS TIME.
TODAY AND TONIGHT...NO BIG CHANGES TO CURRENT FORECAST WITH CONTINUED
MODERATE SOUTHWEST FLOW ALOFT ACROSS THE STATE AS EASTERN UTAH SHORT
WAVE CONTINUES TO TRANSLATE ACROSS THE NORTHERN ROCKIES. THIS WILL
ALLOW LEE TROUGH TO CONTINUE TO PUSH OUT ACROSS THE FAR SE PLAINS
WITH DRY AND BREEZY SOUTHWEST WINDS OF 15 TO 30 MPH MIXING DOWN
ACROSS THE ALL OF SOUTH CENTRAL AND SOUTHEAST COLORADO LATE THIS
MORNING THROUGH THE EARLY EVENING. CURRENT FORECAST USED A BLEND OF
DEW PTS FROM THE HIGHER RES RUC AND HRRR ALONG WITH LOCAL WRF WITH
MIN RHS OF 5-15 PERCENT EXPECTED ACROSS THE AREA TODAY. THIS ALONG
WITH BREEZY WINDS AND RESULTANT WARM TEMPS WILL CREATE CRITICAL FIRE
WEATHER CONDITIONS ACROSS THE AREA AGAIN TODAY...WITH CURRENT RED
FLAG WARNING FOR THE I-25 CORRIDOR WESTWARD REMAINING IN TACT FROM
11AM TO 8PM. FURTHER EAST...RECENT RAINS HAVE HELPED TO TEMPER FIRE
DANGER A TAD WITH AREA LAND MANAGEMENT AGENCIES INDICATING NON
CRITICAL FUELS AT THIS TIME. SOUTHWEST FLOW ALOFT ALONG WITH
EXPECTED PLUMING OF CURRENT ACTIVE FIRES ACROSS THE CWA (EAST
PEAK...WEST FORK...AND BULL GULCH) EXPECTING TO SEE AREAS OF SMOKE
AFFECTING MUCH OF SOUTH CENTRAL AND SOUTHEAST COLORADO TODAY.
NAM CONTINUES TO BE A TAD SLOWER WITH MIXING OUT LOW LEVEL MOISTURE
ACROSS THE FAR SE PLAINS AND TRIES TO DEVELOP A FEW STORMS THIS
AFTERNOON NEAR THE OKLAHOMA AND SW KANSAS BORDERS. HIGHER RES MODELS
KEEP CONVECTION FURTHER EAST...THOUGH HAVE KEPT SILENT POPS ACROSS
THIS AREA AT THIS TIME. MODERATE SW FLOW ALOFT CONTINUES ACROSS THE
AREA TONIGHT AS NEVADA SHORT WAVE CONTINUES TO TRANSLATE NORTH AND
EAST...WITH LEE TROUGHING RE ESTABLISHING ACROSS THE I-25 CORRIDOR
OVERNIGHT. LOW LEVEL MOISTURE MOVES BACK ACROSS THE EASTERN PLAINS
AND TRIES TO MAKE IT INTO THE I-25 CORRIDOR WITH SOUTH TO SOUTHEAST
WINDS. NOT SURE HOW FAR WEST THE MOISTURE WILL MAKE IT BACK...THOUGH
WILL CONTINUE TO BE SHALLOW WITH HIGHER ELEVATIONS AND CURRENT FIRES
HAVING POOR RH RECOVERY ONCE AGAIN TONIGHT.
.LONG TERM...(FRIDAY THROUGH WEDNESDAY)
ISSUED AT 401 AM MDT THU JUN 20 2013
...HOT AND DRY WITH CRITICAL FIRE WEATHER CONDITIONS THROUGH
SATURDAY...
HOT...DRY AND BREEZY/WINDY CONDITIONS ARE EXPECTED OVER THE FORECAST
AREA THROUGH AT LEAST SATURDAY AS SOUTHWESTERLY FLOW REMAINS OVER
THE REGION. THIS SOUTHWESTERLY FLOW IS ASSOCIATED WITH A TROUGH THAT
HAS BEEN OVER THE NORTHWEST CONUS FOR THE LAST FEW DAYS. A FIRE
WEATHER WATCH IS IN EFFECT FOR FRIDAY AND I EXPECT THIS WILL BE
UPGRADED TO A WARNING LATER TODAY. ADDITIONALLY...I ANTICIPATE A NEW
FIRE WEATHER WATCH WILL BE ISSUED FOR SATURDAY FOR THE SAME REGION.
THESE WATCHES MAY NEED TO BE EXPANDED FARTHER EAST AS RH VALUES ARE
EXPECTED TO REACH CRITICAL VALUES OVER MOST OF THE EASTERN PLAINS
FRIDAY AND SATURDAY.
FOR SUNDAY AND MONDAY...THE TROUGH TO OUR NORTHWEST WILL REMAIN BUT
THE GRADIENT WILL SLACKEN A BIT AND THIS WILL ALLOW FOR LESS
WIND...AND FIRE WEATHER CONDITIONS WILL NOT BE AS CRITICAL. IT WILL
STILL BE HOT AND DRY.
INTO NEXT WEEK...FLOW BECOMES ZONAL WITH THE JET LIFTING NORTH.
WINDS WILL MAINLY BE DIURNALLY DRIVEN BUT IT IS EXPECTED TO REMAIN
DRY AND ON THE WARM SIDE.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z FRIDAY MORNING)
ISSUED AT 401 AM MDT THU JUN 20 2013
MAINLY VFR CONDITIONS ARE EXPECTED AT KALS...KCOS...AND KPUB FOR THE
NEXT 24 HOURS...THOUGH PERIODS OF MVFR WILL BE POSSIBLE DUE TO SMOKE
FROM CURRENT WILD FIRES ACROSS THE STATE. GUSTY SOUTH TO SOUTHWEST
WINDS OF 15-30KTS EXPECTED TO DEVELOP THROUGH THE LATE MORNING AND
PERSIST THROUGH THE EARLY EVENING.
&&
.FIRE WEATHER...
ISSUED AT 401 AM MDT THU JUN 20 2013
PLEASE SEE SHORT TERM DISCUSSION FOR FIRE WEATHER CONCERNS FOR
TODAY AND TONIGHT.
LONG TERM FIRE WEATHER CONCERNS...
METEOROLOGICAL CONDITIONS FOR EXTREME FIRE BEHAVIOR WILL OCCUR
OVER THE DISTRICT FRIDAY AT SATURDAY. WINDS OVER THE VALLEYS AND
MTNS WILL GENERA LY RANGE BETWEEN 15 TO 20 MPH WITH GUSTS TO 30
TO 35 MPH.
OVER THE I-25 CORRIDOR...CONDITIONS WILL BE CRITICAL FOR THE MOST
PART. THAT PART OF PUEBLO COUNTY WHICH IS DIRECTLY IN THE LEE OF THE
WET MTNS MAY SEE WINDS BELOW 25 MPH BOTH FRIDAY AND SATURDAY.
FARTHER EAST...IT IS EXPECTED TO DRY OUT FRIDAY AND SATURDAY AS THE
LOW LVL MOISTURE WHICH HAS BEEN OVER THE REGION IS PUSHED WELL INTO
KS. THESE AREAS MAY BE ADDED TO THE FIRE WX HILITES WHICH ARE IN
PLACE FOR THE AREA FOR FRIDAY.
&&
.PUB WATCHES/WARNINGS/ADVISORIES...
RED FLAG WARNING UNTIL 8 PM MDT THIS EVENING FOR COZ220>230.
FIRE WEATHER WATCH FROM FRIDAY MORNING THROUGH FRIDAY EVENING
FOR COZ220>230.
&&
$$
UPDATE...PJC
SHORT TERM...MW
LONG TERM...HODANISH
AVIATION...MW
FIRE WEATHER...HODANISH
AREA FORECAST DISCUSSION
NWS PUEBLO CO
416 AM MDT THU JUN 20 2013
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 401 AM MDT THU JUN 20 2013
...CRITICAL FIRE WEATHER CONDITIONS EXPECTED AGAIN TODAY...
CURRENT WATER VAPOR IMAGERY AND UPPER AIR ANALYSIS INDICATING
MODERATE SOUTHWEST FLOW ALOFT ACROSS THE STATE WITH UPPER LEVEL
RIDGING IN PLACE ACROSS THE HIGH PLAINS ALONG WITH AN UPPER LOW
SPINNING ACROSS THE PACIFIC NORTHWEST AT THIS TIME. WATER VAPOR
IMAGERY ALSO INDICATING AN EMBEDDED SHORT WAVE LIFTING OUT ACROSS
EASTERN UTAH WITH ANOTHER WAVE TRANSLATING ACROSS CENTRAL NEVADA AT
THIS TIME. MSAS DATA AND CURRENT OBS INDICATING LEE TROUGHING ACROSS
THE I-25 CORRIDOR WITH LOWERING PRESSURES ACROSS THE EASTERN PLAINS
AT THIS TIME. SHALLOW LOW LEVEL MOISTURE HAS MADE IT BACK ACROSS THE
I-25 CORRIDOR WITH DEW PTS IN THE 40S AND 50S ACROSS THE EASTERN
PLAINS...THOUGH HIGHER ELEVATION DEW PTS ARE IN THE SINGLE DIGITS
AND TEENS AT THIS TIME. 3.9U IR SATELLITE IMAGERY CONTINUES TO
INDICATE A HOT SPOT SOUTHEAST OF LA VETA PASS ASSOCIATED WITH THE
EAST PEAK/SCOUT RANCH FIRE ALONG WITH ANOTHER HOT SPOT NORTHWEST OF
WOLF CREEK PASS ASSOCIATED WITH THE WEST FORK COMPLEX FIRE.
SATELLITE DATA ALSO INDICATING SMOKE ACROSS THE SAN LUIS VALLEY
THROUGH THE WET MT VALLEY AND INTO PUEBLO AND EL PASO COUNTIES AT
THIS TIME.
TODAY AND TONIGHT...NO BIG CHANGES TO CURRENT FORECAST WITH CONTINUED
MODERATE SOUTHWEST FLOW ALOFT ACROSS THE STATE AS EASTERN UTAH SHORT
WAVE CONTINUES TO TRANSLATE ACROSS THE NORTHERN ROCKIES. THIS WILL
ALLOW LEE TROUGH TO CONTINUE TO PUSH OUT ACROSS THE FAR SE PLAINS
WITH DRY AND BREEZY SOUTHWEST WINDS OF 15 TO 30 MPH MIXING DOWN
ACROSS THE ALL OF SOUTH CENTRAL AND SOUTHEAST COLORADO LATE THIS
MORNING THROUGH THE EARLY EVENING. CURRENT FORECAST USED A BLEND OF
DEW PTS FROM THE HIGHER RES RUC AND HRRR ALONG WITH LOCAL WRF WITH
MIN RHS OF 5-15 PERCENT EXPECTED ACROSS THE AREA TODAY. THIS ALONG
WITH BREEZY WINDS AND RESULTANT WARM TEMPS WILL CREATE CRITICAL FIRE
WEATHER CONDITIONS ACROSS THE AREA AGAIN TODAY...WITH CURRENT RED
FLAG WARNING FOR THE I-25 CORRIDOR WESTWARD REMAINING IN TACT FROM
11AM TO 8PM. FURTHER EAST...RECENT RAINS HAVE HELPED TO TEMPER FIRE
DANGER A TAD WITH AREA LAND MANAGEMENT AGENCIES INDICATING NON
CRITICAL FUELS AT THIS TIME. SOUTHWEST FLOW ALOFT ALONG WITH
EXPECTED PLUMING OF CURRENT ACTIVE FIRES ACROSS THE CWA (EAST
PEAK...WEST FORK...AND BULL GULCH) EXPECTING TO SEE AREAS OF SMOKE
AFFECTING MUCH OF SOUTH CENTRAL AND SOUTHEAST COLORADO TODAY.
NAM CONTINUES TO BE A TAD SLOWER WITH MIXING OUT LOW LEVEL MOISTURE
ACROSS THE FAR SE PLAINS AND TRIES TO DEVELOP A FEW STORMS THIS
AFTERNOON NEAR THE OKLAHOMA AND SW KANSAS BORDERS. HIGHER RES MODELS
KEEP CONVECTION FURTHER EAST...THOUGH HAVE KEPT SILENT POPS ACROSS
THIS AREA AT THIS TIME. MODERATE SW FLOW ALOFT CONTINUES ACROSS THE
AREA TONIGHT AS NEVADA SHORT WAVE CONTINUES TO TRANSLATE NORTH AND
EAST...WITH LEE TROUGHING RE ESTABLISHING ACROSS THE I-25 CORRIDOR
OVERNIGHT. LOW LEVEL MOISTURE MOVES BACK ACROSS THE EASTERN PLAINS
AND TRIES TO MAKE IT INTO THE I-25 CORRIDOR WITH SOUTH TO SOUTHEAST
WINDS. NOT SURE HOW FAR WEST THE MOISTURE WILL MAKE IT BACK...THOUGH
WILL CONTINUE TO BE SHALLOW WITH HIGHER ELEVATIONS AND CURRENT FIRES
HAVING POOR RH RECOVERY ONCE AGAIN TONIGHT.
.LONG TERM...(FRIDAY THROUGH WEDNESDAY)
ISSUED AT 401 AM MDT THU JUN 20 2013
...HOT AND DRY WITH CRITICAL FIRE WEATHER CONDITIONS THROUGH
SATURDAY...
HOT...DRY AND BREEZY/WINDY CONDITIONS ARE EXPECTED OVER THE FORECAST
AREA THROUGH AT LEAST SATURDAY AS SOUTHWESTERLY FLOW REMAINS OVER
THE REGION. THIS SOUTHWESTERLY FLOW IS ASSOCIATED WITH A TROUGH THAT
HAS BEEN OVER THE NORTHWEST CONUS FOR THE LAST FEW DAYS. A FIRE
WEATHER WATCH IS IN EFFECT FOR FRIDAY AND I EXPECT THIS WILL BE
UPGRADED TO A WARNING LATER TODAY. ADDITIONALLY...I ANTICIPATE A NEW
FIRE WEATHER WATCH WILL BE ISSUED FOR SATURDAY FOR THE SAME REGION.
THESE WATCHES MAY NEED TO BE EXPANDED FARTHER EAST AS RH VALUES ARE
EXPECTED TO REACH CRITICAL VALUES OVER MOST OF THE EASTERN PLAINS
FRIDAY AND SATURDAY.
FOR SUNDAY AND MONDAY...THE TROUGH TO OUR NORTHWEST WILL REMAIN BUT
THE GRADIENT WILL SLACKEN A BIT AND THIS WILL ALLOW FOR LESS
WIND...AND FIRE WEATHER CONDITIONS WILL NOT BE AS CRITICAL. IT WILL
STILL BE HOT AND DRY.
INTO NEXT WEEK...FLOW BECOMES ZONAL WITH THE JET LIFTING NORTH.
WINDS WILL MAINLY BE DIURNALLY DRIVEN BUT IT IS EXPECTED TO REMAIN
DRY AND ON THE WARM SIDE.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z FRIDAY MORNING)
ISSUED AT 401 AM MDT THU JUN 20 2013
MAINLY VFR CONDITIONS ARE EXPECTED AT KALS...KCOS...AND KPUB FOR THE
NEXT 24 HOURS...THOUGH PERIODS OF MVFR WILL BE POSSIBLE DUE TO SMOKE
FROM CURRENT WILD FIRES ACROSS THE STATE. GUSTY SOUTH TO SOUTHWEST
WINDS OF 15-30KTS EXPECTED TO DEVELOP THROUGH THE LATE MORNING AND
PERSIST THROUGH THE EARLY EVENING.
&&
.FIRE WEATHER...
ISSUED AT 401 AM MDT THU JUN 20 2013
PLEASE SEE SHORT TERM DISCUSSION FOR FIRE WEATHER CONCERNS FOR
TODAY AND TONIGHT.
LONG TERM FIRE WEATHER CONCERNS...
METEOROLOGICAL CONDITIONS FOR EXTREME FIRE BEHAVIOR WILL OCCUR
OVER THE DISTRICT FRIDAY AT SATURDAY. WINDS OVER THE VALLEYS AND
MTNS WILL GENERA LY RANGE BETWEEN 15 TO 20 MPH WITH GUSTS TO 30
TO 35 MPH.
OVER THE I-25 CORRIDOR...CONDITIONS WILL BE CRITICAL FOR THE MOST
PART. THAT PART OF PUEBLO COUNTY WHICH IS DIRECTLY IN THE LEE OF THE
WET MTNS MAY SEE WINDS BELOW 25 MPH BOTH FRIDAY AND SATURDAY.
FARTHER EAST...IT IS EXPECTED TO DRY OUT FRIDAY AND SATURDAY AS THE
LOW LVL MOISTURE WHICH HAS BEEN OVER THE REGION IS PUSHED WELL INTO
KS. THESE AREAS MAY BE ADDED TO THE FIRE WX HILITES WHICH ARE IN
PLACE FOR THE AREA FOR FRIDAY.
&&
.PUB WATCHES/WARNINGS/ADVISORIES...
RED FLAG WARNING FROM 11 AM THIS MORNING TO 8 PM MDT THIS
EVENING FOR COZ220>230.
FIRE WEATHER WATCH FROM FRIDAY MORNING THROUGH FRIDAY EVENING
FOR COZ220>230.
&&
$$
SHORT TERM...MW
LONG TERM...HODANISH
AVIATION...MW
FIRE WEATHER...HODANISH
AREA FORECAST DISCUSSION
NWS PUEBLO CO
1111 PM MDT WED JUN 19 2013
.SHORT TERM...(THIS EVENING THROUGH THURSDAY)
ISSUED AT 311 PM MDT WED JUN 19 2013
..POSSIBLE ISOLATED SEVERE TONIGHT...CRITICAL FIRE WEATHER CONDITIONS
THURSDAY...
MAIN CONCERN IN THE SHORT TERM IS THE POTENTIAL FOR
THUNDERSTORMS...POSSIBLY SEVERE...ALONG AND EAST OF THE DRY LINE
THIS AFTERNOON AND EVENING. CURRENT SPC MESO ANALYSIS SHOWS 3 TO 4
THOUSAND J/KG OF SBCAPE AND 40KT 0-6KM BULK SHEAR ACROSS THE EASTERN
PLAINS WITH LITTLE CIN. THE LATEST HRRR AND RAP TRY TO INITIATE A
FEW CELLS IN THIS AREA BETWEEN 22Z AND 01Z TONIGHT. ANY STORM THAT
IS ABLE TO INITIATE WILL HAVE A GOOD CHANCE OF PRODUCING LARGE HAIL.
THE LATEST HRRR AND RAP ALSO PUSH THE DRYLINE SLIGHTLY FARTHER WEST
INTO EXTREME EASTERN PUEBLO AND EL PASO COUNTIES AS WELL AS CENTRAL
LAS ANIMAS COUNTY. I HAVE INCREASED POPS TO ISOLATED IN THESE AREAS.
OVER THE REST OF THE REGION...DEWPOINTS WERE QUICK TO DROP WEST OF
THE INTERSTATE INTO THE SINGLE DIGITS THIS MORNING...AND ARE SLOWLY
DROPPING ALONG THE I-25 CORRIDOR AS WINDS CONTINUE TO INCREASE IN
THESE AREAS. THE CURRENT RED FLAG WARNING LOOKS GOOD AND WILL LEAVE IT
INTACT.
THURSDAY...
THE FORECAST AREA WILL REMAIN BETWEEN A QUASISTATIONARY CUT OFF LOW
CENTERED OVER IDAHO AND A BROAD RIDGE OF HIGH PRESSURE CENTERED OVER
TEXAS. THE RESULTING SOUTHWEST FLOW WILL RESULT IN CRITICAL FIRE
WEATHER CONDITIONS ACROSS THE I-25 CORRIDOR AND AREAS WESTWARD.
GUSTY WINDS...LOW DEWPOINTS...AND DRY FUELS WILL PROMOTE EXTREME
FIRE GROWTH IN THESE AREAS. A RED FLAG WARNING HAS BEEN ISSUED
BEGINNING AT 11AM FOR THESE AREA.
THE NAM12/GFS INDICATE THE DRYLINE WILL STILL BE IN SOUTHEASTERN
COLORADO THURSDAY AFTERNOON WITH ISOLATED THUNDERSTORMS POSSIBLE IN
BACA COUNTY. IF THE DRYLINE SETS UP FARTHER WESTWARD THAN CURRENTLY
INDICATED...ADDITIONAL COUNTIES WILL NEED TO BE WATCHED FOR STORM
INITIATION LATE THURSDAY AFTERNOON. -PJC
.LONG TERM...(THURSDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 311 PM MDT WED JUN 19 2013
...CRITICAL FIRE WEATHER CONDITIONS CONTINUE THROUGH THE WEEKEND
INTO EARLY NEXT WEEK...
SOUTHWEST FLOW WILL REMAIN OVER THE REGION THROUGH THE WEEKEND WITH
A REPEAT PERFORMANCE OF CRITICAL FIRE WEATHER CONDITIONS POSSIBLE
AGAIN FOR FRIDAY. THIS LOOKS MOST LIKELY TO OCCUR ACROSS THE
MOUNTAINS AND VALLEYS AND SOUTHERN I-25 CORRIDOR. IT GETS A LITTLE TRICKIER
FOR NORTHERN PORTIONS OF THE I-25 CORRIDOR...MAINLY PUEBLO...EL
PASO...AND TELLER COUNTIES...WITH WIND GUSTS POSSIBLY COMING UP JUST
SHY OF 25 MPH FOR THE REQUIRED 3 HOUR WINDOW. HOWEVER WINDS LOOK A
LITTLE STRONGER ON THE GFS SO WILL GO AHEAD AND INCLUDE THESE AREAS
IN THE FIRE WEATHER WATCH. WITH TEMPERATURES PUSHING 100 ACROSS THE
PLAINS...WITH GENERALLY 60S/70S AND 80S ACROSS THE MTS/VALLEYS...RHS
ALL AREAS DROP TO BETWEEN 5 AND 15 PERCENT. FUELS ARE STILL TOO
MOIST OR HAVE GREENED UP ACROSS THE SOUTHEAST PLAINS EAST OF THE
I-25 CORRIDOR WITH RECENT RAINFALL SO NO HIGHLIGHTS ANTICIPATED FOR
THEM AT THIS TIME.
A SIMILAR SCENARIO IS EXPECTED FOR SATURDAY THOUGH SOUTHERLY WINDS
ADVECT HIGHER DEW POINTS INTO THE SOUTHEAST CORNER OF THE STATE.
ISOLATED THUNDERSTORMS WILL BE POSSIBLE NEAR THE CO/KS BORDER ALONG
THIS DRY LINE. ELSEWHERE...LOOKS LIKE ANOTHER POTENTIAL RED FLAG
DAY.
DRY AND WINDY CONDITIONS CONTINUE FOR SUNDAY AND MONDAY WITH
CRITICAL FIRE WEATHER CONDITIONS LIKELY TO CONTINUE FOR THE I-25
CORRIDOR AND POINTS WESTWARD THROUGH THE PERIOD. IF FUELS DRY OUT
SUFFICIENTLY...ITS POSSIBLE MORE OF THE SOUTHEAST PLAINS MAY NEED TO
BE INCLUDED. CHANCES FOR PRECIPITATION LOOK VERY LOW...THOUGH ECMWF
HAS THE DRY LINE FLIRTING WITH THE EASTERN BORDER.
UPPER RIDGE BUILDS OVER THE AREA FOR TUESDAY AND WEDNESDAY.
ALTHOUGH IT WILL REMAIN HOT AND DRY...THIS DOES HELP TO TAPER BACK
WINDS WHICH WILL ALLEVIATE THE CRITICAL FIRE WEATHER CONDITIONS
SOME. -KT
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z THURSDAY NIGHT)
ISSUED AT 1106 PM MDT WED JUN 19 2013
HAVE ADDED HZ OR FU TO THE TAFS FOR TOMORROW...DUE TO ONGOING
LARGE WILDFIRES ACROSS THE AREA. WINDS ALOFT WILL BE SIMILAR ON
THU AS THEY WERE ON WED...SO EXPECT LARGE PLUME OF SMOKE FROM THE
WEST FORK COMPLEX IN THE SAN JUANS TO ONCE AGAIN BE CARRIED OVER
KCOS. SMOKE MAY DISSIPATE A BIT TONIGHT BUT WILL LIKELY BE A
CONCERN AGAIN THU AFTERNOON. KPUB WILL BE SOMEWHAT REMOVED FROM
THE DIRECT PLUME BUT WILL STILL LIKELY EXPERIENCE HZ FROM THE
FIRES. WITH SKIES SKC...MAIN CONCERN THROUGH TOMORROW WILL
BE THE GUSTY SW WINDS...WHICH COULD BE IN THE 30 PLUS KNOT
RANGE IN THE AFTERNOON. ROSE
&&
.FIRE WEATHER...
ISSUED AT 311 PM MDT WED JUN 19 2013
CRITICAL CONDITIONS FOR FIRE WEATHER WILL CONTINUE FOR THURSDAY
THROUGH MONDAY AS A PROLONGED HOT DRY AND WINDY PATTERN SETS UP
OVER THE DISTRICT. CONDITIONS WILL BE MOST VOLATILE ACROSS THE
MOUNTAIN AREAS...PARTICULARLY ACROSS THE SOUTHWEST AND CENTRAL
MOUNTAINS AND SAN LUIS VALLEY. CRITICAL FIRE WEATHER CONDITIONS
MAY BE A BIT MARGINAL FOR THE PIKES PEAK REGION ON
FRIDAY...HOWEVER WINDS APPEAR TO STRENGTHEN ACROSS ALL OF THE AREA
FOR SATURDAY THROUGH MONDAY. HUMIDITIES WILL DROP TO BETWEEN 5 AND
15 PERCENT EACH AFTERNOON AND WITH HAINES VALUES RUNNING AROUND
6...WHICH WILL LEAD TO CONDITIONS FAVORABLE FOR PLUME DOMINATED
FIRES THROUGH THE PERIOD. ALTHOUGH FUELS ARE NOT CONSIDERED
CRITICAL EAST OF THE I-25 CORRIDOR...HOT DRY CONDITIONS MAY CURE
FUELS AND MAKE THEM RECEPTIVE AGAIN OVER THE WEEKEND...THUS
EXTREME CARE SHOULD BE TAKEN TO AVOID WILDFIRE STARTS THROUGH THIS
HOT DRY PERIOD ACROSS ALL OF SOUTH CENTRAL AND SOUTHEAST COLORADO.
WINDS ARE EXPECTED TO WEAKEN SOME FOR TUESDAY AS HIGH PRESSURE
BUILDS OVER THE REGION...HOWEVER IT IS LIKELY TO REMAIN HOT AND
DRY NONE-THE-LESS. -KT/PJC
&&
.PUB WATCHES/WARNINGS/ADVISORIES...
RED FLAG WARNING FROM 11 AM TO 8 PM MDT THURSDAY FOR COZ220>230.
FIRE WEATHER WATCH FROM FRIDAY MORNING THROUGH FRIDAY EVENING
FOR COZ220>230.
&&
$$
SHORT TERM...PJC
LONG TERM...KT
AVIATION...ROSE
FIRE WEATHER...PJC/KT
AREA FORECAST DISCUSSION
NWS MIAMI FL
224 PM EDT THU JUN 20 2013
.SHORT TERM (TONIGHT-SATURDAY NIGHT)...
AFTER A BUSY START EARLY THIS MORNING ALONG THE EAST COAST WHERE
RAINFALL TOTALS RANGED FROM 1 TO 3 INCHES WITHIN A FEW HOURS BY OR
AROUND SUNRISE...MOST OF THE AFTERNOON SHOWER/TSTM ACTIVITY IS NOW
INLAND AROUND THE LAKE REGION AND ALONG THE GULF COAST NORTH OF
NAPLES. THE LATEST HRRR AND WRF MODEL REFLECTIVITIES
GENERALLY INDICATE THIS EARLY AFTERNOON ACTIVITY CONTINUING TO
DEVELOP AND BECOMING MORE WIDESPREAD ACROSS THESE INTERIOR AND GULF
COAST AREAS THROUGH THE LATE AFTERNOON AND EARLY EVENING PERIODS.
VERY WEAK FLOW DEPICTED IN THE MORNING UPPER AIR SOUNDING WILL
RESULT IN VERY LITTLE STORM MOTION AND MAY TRANSLATE TO FLOODING IN
THE AREAS WHERE THE RAINFALL BECOMES CONCENTRATED. WMSI VALUES FROM
THE MORNING SOUNDING AND THE GFS/NAM/WRF ARW...WHICH ARE BASED ON
MID/SFC THETA-E DIFFERENCES AND SB-CAPE ARE NOT VERY IMPRESSIVE
SPATIALLY ACROSS SOUTH FLORIDA. THEREFORE...THE POTENTIAL FOR STRONG
THUNDERSTORMS WITH GUSTS UP TO 50 MPH APPEARS TO BE LOW AT THIS TIME
WITH THE MAIN THREAT BEING HEAVY RAIN.
TONIGHT THROUGH SATURDAY NIGHT...ELIMINATING THE POTENTIAL FOR
ANOTHER ROUND OF HEAVY RAINFALL SETTING UP ALONG THE EAST COAST
THROUGH THE LATE NIGHT/EARLY MORNING HOURS RESULTING IN RAIN-COOLED
AIR AT THE SURFACE...SIMILAR TO THIS MORNING...OVERNIGHT
TEMPERATURES ARE FORECAST TO REMAIN SEVERAL DEGREES ABOVE AVERAGE
EACH NIGHT. AS A RESULT...WARMEST MINIMUM TEMPERATURE RECORDS COULD
BE BROKEN EACH NIGHT ALONG THE EAST COAST. OTHERWISE...SIMILAR
CONDITIONS ARE EXPECTED TO CONTINUE THROUGH FRIDAY WITH LIGHT
SOUTHEAST LOW-LEVEL FLOW AND INTERIOR AFTERNOON SHOWERS/TSTMS.
FRIDAY NIGHT THROUGH SATURDAY NIGHT...MODELS REMAIN PERSISTENT FROM
RUN TO RUN AND CONTINUE TO INDICATE A TROPICAL WAVE APPROACHING AND
MOVING INTO THE AREA. MODEL PWS ASSOCIATED WITH THIS WAVE ARE
FORECAST TO NEAR THE 2" MARK BY SATURDAY NIGHT...WHICH SHOULD
TRANSLATE TO HIGHER RAIN CHANCES ACROSS THE AREA.
.LONG TERM (SUNDAY-WEDNESDAY)...
THE PREVIOUSLY DISCUSSED WAVE WILL CONTINUE WEST OF THE PENINSULA BY
LATE IN THE WEEKEND AND INTO EARLY NEXT WEEK WITH SOME DRYING ALOFT
ONCE AGAIN SPREADING OVER THE LOCAL AREA. THE MID-LEVEL RIDGE WILL
ALSO REBUILD BACK ACROSS THE PENINSULA WITH A BIT LESS OF
INSTABILITY ALSO IN PLACE AND POPS WILL DROP BACK A LITTLE BELOW THE
AVERAGE FOR LATE JUNE.
30/KOB
&&
.AVIATION...
VFR WILL PREVAIL. MOST OF THE SHOWERS OR STORMS THAT DEVELOP ARE
FORECAST TO BE ACROSS THE INTERIOR. THE FORECAST REASONING IS THAT
DIURNAL CONVECTION IS EXPECTED FOR TODAY WITH MOST OF THE ACTIVITY
EXPECTED TO LAST INTO LATE EVENING FOR THE INTERIOR AND WEST COAST.
FOR NOW HAS KEPT VCSH FOR ALL TERMINALS SINCE THERE IS A LAYER OF
DRY AIR VISIBLE FROM THE SOUNDING AROUND 700MB. THIS COULD SLOW DOWN
THE FORMATION OF CONVECTION. BY THE TIME THAT CONVECTION FORMS IT
MAY FOCUS MORE ALONG THE SEA BREEZES WHICH WOULD HAVE ALREADY PUSHED
FURTHER INLAND. DRIER CONDITIONS ARE EXPECTED ON FRIDAY DUE TO DRIER
AIR MOVING INTO THE AREA FROM THE EAST.
&&
.MARINE...
LIGHT TO MODERATE SOUTHEAST WINDS ASSOCIATED WITH HIGH PRESSURE WILL
PERSIST THROUGH THE REMAINDER OF THE WEEK. THE BEST CHANCE FOR
ISOLATED SHOWERS AND STORMS WILL BE THROUGH THE OVERNIGHT AND EARLY
MORNING HOURS EACH DAY. A WEAK TROPICAL WAVE WILL APPROACH AND MOVE
THROUGH THE MARINE AREA OVER THE WEEKEND AND MAY TRANSLATE TO BETTER
SHOWER/TSTM COVERAGE.
&&
.FIRE WEATHER...
RELATIVE HUMIDITIES ARE FORECAST TO REMAIN ABOVE CRITICAL LEVELS
EACH DAY. LIGHT SOUTHEAST WINDS ARE EXPECTED TO PERSIST THROUGH MUCH
OF THE WEEK...EXCEPT THROUGH THE AFTERNOON PERIODS AS THE GULF COAST
SEA BREEZES PENETRATES INLAND ACROSS PORTIONS OF COLLIER COUNTY.
&&
.PRELIMINARY POINT TEMPS/POPS...
WEST PALM BEACH 77 87 78 88 / 20 20 20 50
FORT LAUDERDALE 79 88 80 88 / 20 20 20 50
MIAMI 79 89 79 88 / 20 20 20 50
NAPLES 74 93 73 91 / 20 30 20 40
&&
.MFL WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
AM...NONE.
GM...NONE.
&&
$$
SHORT TERM/MARINE/FIRE...85/AG
LONG TERM...30/KOB
AVIATION/RADAR...71/JE
AREA FORECAST DISCUSSION
NWS TALLAHASSEE FL
1050 AM EDT Thu Jun 20 2013
.NEAR TERM [Through Tonight]...
A weak stalled frontal boundary that has been present over our
area the past few days appears to have diminished. A hand-drawn
13Z mesoscale surface analysis doesn`t provide enough evidence to
suggest that there is a frontal boundary present.
Have tweaked the current grids today to represent the current
thinking of the evolution of today`s weather. High-resolution
models such as our local WRF and the HRRR suggest a high coverage
of thunderstorms initiating over the coastal Florida Panhandle and
then spreading through most of our Florida counties by 19Z.
Therefore have went with a 70-40% south to north PoP gradient,
with the greatest chance of thunderstorms(60-70%) in our Florida counties.
Raised high temperatures in south Georgia and southeast Alabama
to around 95. Otherwise expect highs to reach the lower 90s across
much of the CWA.
The threat for severe thunderstorms today seems low, but an
isolated severe storm cannot be ruled out. If an isolated severe
storm does form the main threat would be damaging wind gusts.
&&
.SHORT TERM [Friday Through Friday Night]...
Weak troughs at the surface and aloft are forecast to remain in
place along the northeastern Gulf Coast through Saturday. These
features will help to provide some enhancement to the typical
afternoon seabreeze convection.
For Friday, the surface trough will be situated southwest to
northeast across the area. With light onshore flow to the east of
the trough axis, expect highest PoPs over the Big Bend and south
central Georgia. PoPs will range from the 60s in the eastern Big
Bend to the 30s across SE Alabama and SW Georgia.
The surface trough will slide to the northwest on Saturday,
allowing for the onshore low-level flow to spread across most of
the forecast area. With the weak trough aloft and increased deep
layer moisture, expect an active day of convection on Saturday
with PoPs in the high chance to likely category area-wide.
Temperatures are expected to reach the upper 80s to lower 90s both
Friday and Saturday afternoons.
&&
.LONG TERM [Saturday through Wednesday]...
Pattern will support seasonal conditions through the early part
of next week with afternoon highs inland in the lower 90s along
with a chance of afternoon/evening showers and thunderstorms each
day. Overall, rather benign mid and upper level pattern is
expected to become established by the weekend and result in little
day to day change.
&&
.AVIATION...
[Through 12 UTC Saturday] The main focus of this TAF period will
be the afternoon thunderstorms that are expected to develop
beginning around 18Z. There is relatively high confidence is storm
coverage at ECP, TLH and VLD this afternoon. VFR conditions should
prevail til right before sunrise where low CIGs and patchy fog
will likely develop.
&&
.MARINE...
A weak trough of low pressure over the waters will keep winds and
seas minimal into the weekend. Southeasterly flow will develop by
Saturday as the subtropical ridge slides to the north. However,
winds and seas will remain low with no headlines anticipated into
early next week.
&&
.FIRE WEATHER...
Relative humidity values will remain above critical levels for
the next several days. Thus, red flag conditions are not expected.
&&
.HYDROLOGY...
No significant rises are anticipated on area rivers into next week.
&&
.PRELIMINARY POINT TEMPS/POPS...
Tallahassee 91 70 89 70 89 / 60 40 50 40 60
Panama City 89 74 88 74 87 / 70 30 40 30 40
Dothan 95 71 91 70 89 / 40 20 30 30 50
Albany 92 70 89 70 89 / 40 20 30 30 50
Valdosta 94 70 89 69 88 / 40 50 50 40 60
Cross City 90 70 90 69 90 / 60 50 60 50 60
Apalachicola 88 74 87 74 86 / 60 30 30 30 30
&&
.TAE WATCHES/WARNINGS/ADVISORIES...
FL...None.
GA...None.
AL...None.
GM...None.
&&
$$
NEAR TERM...Navarro/Harrigan
SHORT TERM...Camp
LONG TERM...Evans
AVIATION...Navarro/Harrigan
MARINE...Navarro/Harrigan
FIRE WEATHER...Camp
HYDROLOGY...Camp
AREA FORECAST DISCUSSION
NWS LINCOLN IL
920 PM CDT FRI JUN 21 2013
.DISCUSSION...
ISSUED 915 PM CDT FRI JUN 21 2013
WITH THE REMAINS OF THE DYING MCS MOVING OUT OF THE STATE TO THE
EAST/SE...PULLING POPS IN THE OVERNIGHT FOR THE AREA. KEEPING SOME
SLIGHTS IN THE EAST FOR ANY REDEVELOPMENT...BUT THE SYSTEM IS
PULLING TOO FAR TO THE EAST AND THE CURRENT RUC/RAPP RUN IS MOSTLY
DRY IN THE OVERNIGHT. ONLY CONCERN FOR THE OVERNIGHT IS THE
POTENTIAL FOR PATCHY FOG WITH THE MOISTURE IN THE BOUNDARY LAYER
DUE TO THE STORMS. BUT THE DWPTS ARE ACTUALLY LOWER IN THE AREAS
THAT SAW RAIN...AND WELL BELOW THE EXPECTED LOWS. WILL CONTINUE
TO MONITOR...UPDATES OUT MOMENTARILY.
HJS
&&
.AVIATION...
ISSUED 656 PM CDT FRI JUN 21 2013
IN THE WAKE OF THIS EVENINGS MCS...WINDS BECOMING MORE S/SERLY
ONCE AGAIN...AND LOSING THE GUSTS AS THE SUN SETS. VFR SHOULD
DOMINATE THE OVERNIGHT HOURS AS THE LOW CLOUDS SCATTER OUT.
TOMORROW GUSTS RETURN AS WINDS PICK UP A SOUTHWESTERLY FETCH AND
CU REDEVELOPS. ANOTHER MCS LIKELY TO PUT DOWN AN OUTFLOW/REMNANT
MCV WHICH MAY BE THE TRIGGER FOR ANOTHER ROUND OF TS TOMORROW
AFTERNOON. TEMPO INTO COVER THE BEST TIMING FOR NOW. MAY NEED TO
ADJUST THE TIMING... BUT HAVE STARTED THE TREND.
HJS
&&
.PREV DISCUSSION...
ISSUED 300 PM CDT FRI JUN 21 2013
INITIAL CONCERNS WILL FOCUS ON THE SEVERE POTENTIAL WITH THE LINE
OF STORMS MOVING ACROSS OUR NORTHERN COUNTIES. THEN ATTENTION
TURNS TO THE HEAT AND HUMIDITY WITH PERIODIC STORM CHANCES IN THIS
SUMMER PATTERN. THE EXTENDED FORECAST STILL CALLS FOR OUR NEXT
COLD FRONT TO ARRIVE AROUND THURSDAY.
SHORT TERM...TONIGHT THROUGH MONDAY.
A 30-40 MPH SOUTHWARD MOVING GUST FRONT IS GENERALLY OUTRUNNING
THE LINE OF STORMS BY 5 TO 10 MILES IN MOST AREAS...EXCEPT FOR IN
THE MID-PORTION OF THE LINE FROM DELAVAN TO BLOOMINGTON. STORM
INITIATION REMAINS CLOSER TO THE GUST FRONT IN THAT AREA. THOSE
STORMS ARE THE STRONGEST AT 230 PM...BUT STILL APPEAR TO BE SUB-
SEVERE. HAIL AND WIND REPORTS HAVE BEEN SPARSE, BUT A FEW TREE LIMBS
MAY HAVE BEEN KNOCKED DOWN NEAR DUNLAP AND THE LARGEST HAIL REPORT
WAS DIME SIZED 1N OF MOSSVILLE EARLIER. STORM INTENSITY HAS
GENERALLY WEAKENED SINCE THOSE REPORTS...SO WE CONTINUE TO MONITOR
FOR ANY INTENSIFICATION. SPC MESO-ANALYSIS PAGE SHOWS MORE STABLE
AIR AHEAD OF THE STORMS...WITH WEAKER 0-6KM BULK SHEAR. THERE IS
STILL 1500 J/KG MUCAPE AVAILABLE...SO THE STORMS MAY LINGER AT
LEAST UNTIL THE INDIANA BORDER EARLY THIS EVENING.
INTO EARLY EVENING...A COUPLE 4KM MODELS ARE SHOWING ADDITIONAL
STORM DEVELOPMENT FARTHER WEST IN EASTERN IOWA/NE MO WHERE
INSTABILITY AND SHEAR PARAMS ARE MORE FAVORABLE FOR STORMS.
HOWEVER...THE 18Z HRRR RUN DOES NOT HAVE ANY INDICATION OF THOSE
STORMS. TAKING EVERYTHING INTO CONSIDERATION...WE TRIED TO MAKE
THE POPS/WEATHER GRIDS CONFORM CLOSELY TO THE NEXT 3-5 HOURS OF
CONVECTION...THEN WENT MORE GENERAL BASED ON SATELLITE, RADAR AND
OBSERVATION TRENDS. WE LINGERED SOME HIGHER POPS THROUGH 03Z THIS
EVENING IN THE EAST TO TREND THE CURRENT STORMS EASTWARD...WITH
SLIGHT CHANCE IN OUR WESTERN COUNTIES TO COVER THE NEXT LINE THAT
MAY ARRIVE.
THE REST OF THE NIGHT SHOULD BE MUGGY AND MILD...AS CLOUDS CLEAR
OUT AND LINGERING NORTH WINDS BEHIND THIS LINE OF STORMS RETURNS
TO SOUTHERLY.
SATURDAY WILL BRING ANOTHER ROUND OF AFTERNOON SHOWERS AND STORMS
AS HIGHS CLIMB INTO THE LOWER 90S AND HEAT INDICES REACH AROUND
100. SEVERE CHANCES SHOULD REMAIN LOW IN OUR COUNTIES...WITH THE
SLIGHT RISK FOR DAY 2 NW OF ILLINOIS. THE TRIGGERS FOR STORMS MAY
BE TIED TO THE RESIDUAL OUTFLOW BOUNDARIES FROM TODAY`S
CONVECTION...AND THE PASSAGE OF A WEAK 500 MB SHORTWAVE.
PRECIPITABLE WATER VALUES AROUND 1.75" WILL ALLOW SOME OF THE
STRONGER STORMS TO BE VERY HEAVY RAIN PRODUCERS...WITH RAINFALL
RATES OF 1-2" PER HOUR. LOCALIZED FLASH FLOODING WILL BE
POSSIBLE...DESPITE THE RELATIVELY DRY CONDITIONS OVER THE PAST
COUPLE OF WEEKS IN MOST AREAS. STORMS SHOULD COME TO AN END BY
SATURDAY EVENING...WITH CLEARING SKIES OVERNIGHT.
SUNDAY WILL SEE LESS FAVORABLE INSTABILITY PARAMS...AS MID LEVEL
WARMING PROVIDES A BETTER CAP ON STORM DEVELOPMENT. WE KEPT A DRY
FORECAST FOR SUNDAY...BUT KEPT THE HEAT AND HUMIDITY HIGH. HEAT
INDEX READING SHOULD REMAIN BELOW SATURDAYS READINGS...BUT STILL
IN THE MID TO UPPER 90S.
MONDAY WILL SEE THE RETURN OF STORM CHANCES AS THE NEXT 500MB
SHORTWAVE CREATES SOME FALLING HEIGHTS AND DESTABILIZES THE LOWER
TROPOSPHERE. STORM DEVELOPMENT SHOULD OCCUR IN THE AFTERNOON...AS
SURFACE HEATING HELPS TO ERODE THE CAP. WE WENT WITH CHANCE POPS
IN THE NW HALF OF OUR FORECAST AREA...WITH SLIGHTS DOWN TO I-70.
LONG TERM...TUESDAY THROUGH FRIDAY.
ANOTHER LULL IN THE STORMS IS EXPECTED MONDAY NIGHT THRU TUESDAY
NIGHT...AS THE UPPER TROUGH IN THE N PLAINS BEGINS TO BECOME
PROGRESSIVE. AS THE UPPER TROUGH REACHES THE GREAT LAKES...A
SURFACE COLD FRONT IS FORECAST TO MOVE ACROSS ILLINOIS ON THURSDAY
OR THURSDAY NIGHT. SHOWERS AND STORMS WILL LIKELY DEVELOP ALONG
THAT FEATURE...DESPITE THE WEAKER APPEARANCE OF THE FRONT IN THE
EXTENDED MODELS.
THE NORTHWEST FLOW BEHIND THAT COLD FRONT WILL HELP DROP HIGHS
FROM THE LOW 90S ON TUESDAY AND WED...BACK INTO THE UPPER 80S
THURSDAY AND LOWER 80S ON FRIDAY. DEWPOINTS WILL DROP INTO THE
LOWER 60S ON FRIDAY AS WELL...PROVIDING SOME RELIEF FROM THE HEAT
AND HUMIDITY.
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS LINCOLN IL
708 PM CDT FRI JUN 21 2013
.DISCUSSION...
ISSUED 300 PM CDT FRI JUN 21 2013
INITIAL CONCERNS WILL FOCUS ON THE SEVERE POTENTIAL WITH THE LINE
OF STORMS MOVING ACROSS OUR NORTHERN COUNTIES. THEN ATTENTION
TURNS TO THE HEAT AND HUMIDITY WITH PERIODIC STORM CHANCES IN THIS
SUMMER PATTERN. THE EXTENDED FORECAST STILL CALLS FOR OUR NEXT
COLD FRONT TO ARRIVE AROUND THURSDAY.
SHORT TERM...TONIGHT THROUGH MONDAY.
A 30-40 MPH SOUTHWARD MOVING GUST FRONT IS GENERALLY OUTRUNNING
THE LINE OF STORMS BY 5 TO 10 MILES IN MOST AREAS...EXCEPT FOR IN
THE MID-PORTION OF THE LINE FROM DELAVAN TO BLOOMINGTON. STORM
INITIATION REMAINS CLOSER TO THE GUST FRONT IN THAT AREA. THOSE
STORMS ARE THE STRONGEST AT 230 PM...BUT STILL APPEAR TO BE SUB-
SEVERE. HAIL AND WIND REPORTS HAVE BEEN SPARSE, BUT A FEW TREE LIMBS
MAY HAVE BEEN KNOCKED DOWN NEAR DUNLAP AND THE LARGEST HAIL REPORT
WAS DIME SIZED 1N OF MOSSVILLE EARLIER. STORM INTENSITY HAS
GENERALLY WEAKENED SINCE THOSE REPORTS...SO WE CONTINUE TO MONITOR
FOR ANY INTENSIFICATION. SPC MESO-ANALYSIS PAGE SHOWS MORE STABLE
AIR AHEAD OF THE STORMS...WITH WEAKER 0-6KM BULK SHEAR. THERE IS
STILL 1500 J/KG MUCAPE AVAILABLE...SO THE STORMS MAY LINGER AT
LEAST UNTIL THE INDIANA BORDER EARLY THIS EVENING.
INTO EARLY EVENING...A COUPLE 4KM MODELS ARE SHOWING ADDITIONAL
STORM DEVELOPMENT FARTHER WEST IN EASTERN IOWA/NE MO WHERE
INSTABILITY AND SHEAR PARAMS ARE MORE FAVORABLE FOR STORMS.
HOWEVER...THE 18Z HRRR RUN DOES NOT HAVE ANY INDICATION OF THOSE
STORMS. TAKING EVERYTHING INTO CONSIDERATION...WE TRIED TO MAKE
THE POPS/WEATHER GRIDS CONFORM CLOSELY TO THE NEXT 3-5 HOURS OF
CONVECTION...THEN WENT MORE GENERAL BASED ON SATELLITE, RADAR AND
OBSERVATION TRENDS. WE LINGERED SOME HIGHER POPS THROUGH 03Z THIS
EVENING IN THE EAST TO TREND THE CURRENT STORMS EASTWARD...WITH
SLIGHT CHANCE IN OUR WESTERN COUNTIES TO COVER THE NEXT LINE THAT
MAY ARRIVE.
THE REST OF THE NIGHT SHOULD BE MUGGY AND MILD...AS CLOUDS CLEAR
OUT AND LINGERING NORTH WINDS BEHIND THIS LINE OF STORMS RETURNS
TO SOUTHERLY.
SATURDAY WILL BRING ANOTHER ROUND OF AFTERNOON SHOWERS AND STORMS
AS HIGHS CLIMB INTO THE LOWER 90S AND HEAT INDICES REACH AROUND
100. SEVERE CHANCES SHOULD REMAIN LOW IN OUR COUNTIES...WITH THE
SLIGHT RISK FOR DAY 2 NW OF ILLINOIS. THE TRIGGERS FOR STORMS MAY
BE TIED TO THE RESIDUAL OUTFLOW BOUNDARIES FROM TODAY`S
CONVECTION...AND THE PASSAGE OF A WEAK 500 MB SHORTWAVE.
PRECIPITABLE WATER VALUES AROUND 1.75" WILL ALLOW SOME OF THE
STRONGER STORMS TO BE VERY HEAVY RAIN PRODUCERS...WITH RAINFALL
RATES OF 1-2" PER HOUR. LOCALIZED FLASH FLOODING WILL BE
POSSIBLE...DESPITE THE RELATIVELY DRY CONDITIONS OVER THE PAST
COUPLE OF WEEKS IN MOST AREAS. STORMS SHOULD COME TO AN END BY
SATURDAY EVENING...WITH CLEARING SKIES OVERNIGHT.
SUNDAY WILL SEE LESS FAVORABLE INSTABILITY PARAMS...AS MID LEVEL
WARMING PROVIDES A BETTER CAP ON STORM DEVELOPMENT. WE KEPT A DRY
FORECAST FOR SUNDAY...BUT KEPT THE HEAT AND HUMIDITY HIGH. HEAT
INDEX READING SHOULD REMAIN BELOW SATURDAYS READINGS...BUT STILL
IN THE MID TO UPPER 90S.
MONDAY WILL SEE THE RETURN OF STORM CHANCES AS THE NEXT 500MB
SHORTWAVE CREATES SOME FALLING HEIGHTS AND DESTABILIZES THE LOWER
TROPOSPHERE. STORM DEVELOPMENT SHOULD OCCUR IN THE AFTERNOON...AS
SURFACE HEATING HELPS TO ERODE THE CAP. WE WENT WITH CHANCE POPS
IN THE NW HALF OF OUR FORECAST AREA...WITH SLIGHTS DOWN TO I-70.
LONG TERM...TUESDAY THROUGH FRIDAY.
ANOTHER LULL IN THE STORMS IS EXPECTED MONDAY NIGHT THRU TUESDAY
NIGHT...AS THE UPPER TROUGH IN THE N PLAINS BEGINS TO BECOME
PROGRESSIVE. AS THE UPPER TROUGH REACHES THE GREAT LAKES...A
SURFACE COLD FRONT IS FORECAST TO MOVE ACROSS ILLINOIS ON THURSDAY
OR THURSDAY NIGHT. SHOWERS AND STORMS WILL LIKELY DEVELOP ALONG
THAT FEATURE...DESPITE THE WEAKER APPEARANCE OF THE FRONT IN THE
EXTENDED MODELS.
THE NORTHWEST FLOW BEHIND THAT COLD FRONT WILL HELP DROP HIGHS
FROM THE LOW 90S ON TUESDAY AND WED...BACK INTO THE UPPER 80S
THURSDAY AND LOWER 80S ON FRIDAY. DEWPOINTS WILL DROP INTO THE
LOWER 60S ON FRIDAY AS WELL...PROVIDING SOME RELIEF FROM THE HEAT
AND HUMIDITY.
&&
.AVIATION...
ISSUED 656 PM CDT FRI JUN 21 2013
IN THE WAKE OF THIS EVENINGS MCS...WINDS BECOMING MORE S/SERLY
ONCE AGAIN...AND LOSING THE GUSTS AS THE SUN SETS. VFR SHOULD
DOMINATE THE OVERNIGHT HOURS AS THE LOW CLOUDS SCATTER OUT.
TOMORROW GUSTS RETURN AS WINDS PICK UP A SOUTHWESTERLY FETCH AND
CU REDEVELOPS. ANOTHER MCS LIKELY TO PUT DOWN AN OUTFLOW/REMNANT
MCV WHICH MAY BE THE TRIGGER FOR ANOTHER ROUND OF TS TOMORROW
AFTERNOON. TEMPO INTO COVER THE BEST TIMING FOR NOW. MAY NEED TO
ADJUST THE TIMING... BUT HAVE STARTED THE TREND.
HJS
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
229 AM CDT THU JUN 20 2013
.DISCUSSION...
845 PM CDT
THE ONLY REAL CHANGE MADE TO GOING FORECAST THE REST OF TONIGHT
WAS TO BOOST UP CLOUD COVER. HIGH AND EVEN A FEW MID CLOUDS
ASSOCIATED WITH A SHEARED OUT SHORTWAVE AND VERY ELEVATED /500MB+/
AXIS OF MOIST RETURN CONTINUE TO STREAM ENE INTO THE AREA. THE
REMNANT SHORT WAVE CIRCULATION IS SEEN ACROSS SE IA ON VISIBLE AND
IR. THE OVERALL COVERAGE OF CLOUDS LOOKS LIKE IT HAS FADED IN THE
PAST HOUR AND RAP FORECAST RH CONTINUES THIS GRADUAL DIMINISHING
TREND AS THE AREA COMES ACROSS. SATELLITE ALONG WITH VISUAL
OBSERVATION OUT THE WINDOW WOULD INDICATE HOWEVER WE WOULD STILL
BE DEALING WITH A PARTLY CLOUDY SKY FOR A WHILE. SO HAVE BOOSTED
CLOUD COVER UP SOME. WHILE THE SURFACE RIDGE AXIS REMAINS ACROSS
MI INTO NE IL...THESE CLOUDS MAY BEGIN TO STUNT THE TEMPERATURE
DROP SOME. GOING MINS STILL LOOK ALRIGHT THOUGH AND IN LINE WITH
18Z GUIDANCE. IF CLOUDS LINGER THROUGH THE ENTIRE OVERNIGHT ITS
LIKELY MINS WILL BE 3-5 DEGREES WARMER. IT IS ALWAYS A CHALLENGE
TO PREDICT 15000 FT AND HIGHER CLOUD BEHAVIOR...BUT WILL NOT
COMPLAIN THAT IS THE ONLY REAL FORECAST CHALLENGE TONIGHT.
MTF
//PREV DISCUSSION...
322 PM CDT
MAIN FORECAST CONCERNS/CHALLENGES ARE WITH PRECIP TRENDS OVER THE
NEXT SEVERAL DAYS WITH THUNDERSTORM CHANCES INTO THE WEEKEND...AS
WELL AS A WARMER AND MORE MOIST ENVIRONMENT SETTLING INTO THE AREA
BEGINNING AS EARLY AS TOMORROW.
QUIET AND PLEASANT CONDITIONS IN PLACE ACROSS THE AREA THIS
AFTERNOON AS HIGH PRESSURE SPANS MUCH OF THE REGION. PARTLY
CLOUDY/SUNNY SKIES AND TEMPS GENERALLY IN THE 70S...EXCEPT FOR 60S
NEAR THE LAKE...AS WELL AS LOWER DEWPOINT AIR IN PLACE HAVE
PROVIDED THESE PLEASANT CONDITIONS. ALTHOUGH A SIGN TO COME OF A
WARMER AIRMASS DEFINITELY MOVING UP ACROSS THE REGION ARE WITH THE
LOW/MID 80S TEMPS DRAWING CLOSE TO THE SOUTHERN CWA THIS
AFTERNOON...AS LOW LEVEL WIND FIELD ALREADY TRYING TO FLOP OVER TO
MORE OF A SOUTHERLY DIRECTION. A TREND TOWARDS ABOVE NORMAL TEMPS
WILL OCCUR OVER THE NEXT SEVERAL DAYS INITIALLY FOR AREAS AWAY
FROM THE LAKE TOMORROW BUT WITH THIS TREND EXTENDING TOWARDS AREAS
NEAR THE LAKE BY FRIDAY AS SOUTHERLY WINDS LOOK TO BE IN
PLACE...AND ALSO REMAIN IN PLACE.
DESPITE CURRENT HIGH PRESSURE BEGINNING TO SLOWLY DRIFT EAST OF
THE AREA TONIGHT...QUIET WEATHER WITH MOSTLY CLEAR SKIES WILL BE
OBSERVED ONCE AGAIN WITH NIGHT TIME LOWS DIPPING DOWN TO THE
MID/UPPER 50S FOR MOST AREAS AND EVEN STAYING IN THE LOWER 60S
ACROSS THE SOUTHERN CWA. WITH THIS HIGH CONTINUING TO SLOWLY SHIFT
EAST ON THURSDAY...IT DOES APPEAR AS IF MOST OF THE DAY WILL
REMAIN DRY ACROSS THE CWA. ALTHOUGH...GUIDANCE IS HINTING AT THE
POSSIBILITY FOR SOME CONVECTIVE ACTIVITY IN THE AFTERNOON
PRIMARILY OVER NORTHERN/NORTHWEST ILLINOIS AND CANT COMPLETELY
RULE IT OUT AT THIS TIME. CURRENT UPSTREAM MID LEVEL TROUGH OVER
THE CENTRAL PLAINS WILL WORK ITS WAY EAST TOWARDS THE CWA ON
THURSDAY WITH FORECAST SOUNDINGS INDICATING SOME MOISTENING OF THE
COLUMN...AS SOUTHERLY FLOW AIDS IN THE RETURN OF THIS MORE MOIST
ENVIRONMENT. AS WEAK FORCING MOVES OVER NORTHERN ILLINOIS WITH THE
APPROACH OF THIS WAVE WHILE WEAK INSTABILITY ALSO SETTLES BACK IN
ACROSS THE CWA WITH MINIMAL CIN BY THE AFTERNOON...COULD SEE AT
LEAST ISOLATED SHOWERS/THUNDERSTORMS THURSDAY AFTERNOON WORTHY OF
SLIGHT CHANCE POPS AT THIS TIME.
ALTHOUGH THE CURRENT NAM IS INDICATING CONVECTION REMAINING
OVERHEAD THROUGH THURSDAY EVENING...DO FEEL AS IF IT IS A BIT
BULLISH. THE MAJORITY OF ANY CONVECTION ON THURSDAY SHOULD BE
DIURNALLY DRIVEN WITH A DIMINISHING TREND THEN EXPECTED INTO THE
EVENING...AS THE FOCUS OF MORE WIDESPREAD DEVELOPMENT TO REMAIN
WELL TO THE NORTH OF THE CWA MORE TOWARDS THE STRONGER WESTERLIES
AND LLJ FOCUS. STILL...PERSISTENT WAA ALONG AND JUST WEST OF THE
CWA COULD HELP STEER SOME LINGERING SHOWERS/THUNDERSTORMS ACROSS
NORTHWEST ILLINOIS AND HAVE MAINTAINED THE CURRENT SLIGHT CHANCE
POPS FOR THE FAR NORTHWEST TIER OF COUNTIES LATE THURSDAY NIGHT.
AS A STRONGER WAVE/WAA MOVE ACROSS THE REGION ON FRIDAY...SHOULD
OBSERVE BETTER CHANCES FOR SHOWERS/THUNDERSTORMS ESPECIALLY INTO
THE AFTERNOON. OVERALL WEAK FLOW ALOFT IS EXPECTED ACROSS THE CWA
ON FRIDAY WITH THE STRONGER WESTERLIES ONCE AGAIN REMAINING JUST
TO THE NORTH. ALTHOUGH...WITH INSTABILITY/MOISTURE REALLY
INCREASING DURING THE PERIOD...WILL NEED TO MONITOR THE POTENTIAL
FOR STRONG THUNDERSTORMS TO DEVELOP FRIDAY AFTERNOON. CONFIDENCE
BEGINS TO LOWER FRIDAY NIGHT INTO THE WEEKEND WITH OVERALL
CONVECTIVE TRENDS. ALTHOUGH IT DOES APPEAR THAT THERE WILL REMAIN
CHANCES FOR SHOWERS/THUNDERSTORMS INTO THE CWA ESPECIALLY AS A
MOIST AND UNSTABLE ENVIRONMENT SETTLES IN BUT WITH A MORE FAVORED
LOCATION TO BE ACROSS THE NORTHERN HALF OF THE CWA...AS THE AREA
WILL BE CLOSER TO STRONGER WESTERLIES/PASSING MID LEVEL FEATURES.
RODRIGUEZ
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 06Z...
* LAKE BREEZE THURSDAY AFTERNOON.
* POTENTIAL FOR CONVECTION ALONG THE LAKE BREEZE.
BMD
//DISCUSSION...UPDATED 06Z...
MOST OF THE FORECAST SHOULD BE QUIET AS HIGH PRESSURE CONTINUES TO
DOMINATE THE AREA. THE HIGH OFF TO OUR EAST WILL CONTINUE TO SETTLE
SOUTHEAST OVER THE MID ATLANTIC COAST WITH EASTERLY WINDS OVERNIGHT
FAVORING A MORE SOUTHERLY DIRECTION THURSDAY. THE EXCEPTION WILL BE
AT ORD/MDW WHERE A LAKE BREEZE MAY TURN WINDS BACK TO THE SOUTHEAST
THURSDAY AFTERNOON AND EVENING. MODELS INDICATE MODERATE INSTABILITY
DEVELOPING THURSDAY AFTERNOON WITH LITTLE CAPPING. THERE MAY BE A
FEW SHOWERS OR THUNDERSTORMS THAT DEVELOP ALONG THE LAKE BREEZE
BOUNDARY AND THEN DRIFT EAST OVER LAKE MICHIGAN. THAT SAID...THE
CONVERGENCE ALONG THE FRONT WILL BE SOMEWHAT WEAK LEADING TO LITTLE
CONFIDENCE IN THIS SCENARIO PANNING OUT. THE POTENTIAL IS TOO LOW AT
THIS TIME FOR MENTION IN THE TAF.
BMD
//ORD AND MDW CONFIDENCE...UPDATED 06Z...
* MEDIUM CONFIDENCE IN WIND TRENDS.
* LOW CONFIDENCE IN SHRA/TSRA THURSDAY AFTERNOON.
* HIGH CONFIDENCE IN REMAINING FORECAST ELEMENTS.
BMD
//OUTLOOK FOR ORD/MDW FOR 12Z FRIDAY-12Z WEDNESDAY...UPDATED 00Z...
FRIDAY THROUGH TUESDAY...PERIODIC CHANCES FOR TSRA...ELSE VFR.
ZEBIC
&&
.MARINE...
228 AM CDT
HIGH PRESSURE IS CENTERED OVER NEW ENGLAND BUT ITS INFLUENCE STILL
STRETCHES ACROSS THE GREAT LAKES EARLY THIS MORNING. THE HIGH WILL
SETTLE SOUTHEAST OVER THE MID ATLANTIC COAST TODAY ALLOWING THE
GRADIENT TO INCREASE GRADUALLY OVER THE NEXT 24 HOURS AS LOW
PRESSURE LIFTS FROM THE PLAINS INTO THE CANADIAN PRAIRIES. THIS WILL
ALLOW WINDS TO FRESHEN UP...PARTICULARLY FRIDAY WHEN THE NORTHERN
PORTIONS OF LAKE MICHIGAN WILL INCREASE TO 20 TO 25 KT POSSIBLY EVEN
30 KT. THERE IS A GOOD CHANCE THAT A COUPLE STRONG TO SEVERE
THUNDERSTORMS COMPLEXES COULD MOVE ACROSS LAKE MICHIGAN FRIDAY NIGHT
THROUGH THE WEEKEND. THIS WILL LIKELY DISRUPT THE WIND FIELD FOR A
WHILE LENDING TO DECREASED CONFIDENCE IN THE WIND FORECAST OVER THE
WEEKEND. SOUTH TO SOUTHWEST WINDS ARE EXPECTED TO CONTINUE ACROSS
THE LAKE THROUGH THE MIDDLE OF NEXT WEEK.
BMD
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...NONE.
&&
$$
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AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
1227 AM CDT THU JUN 20 2013
.DISCUSSION...
845 PM CDT
THE ONLY REAL CHANGE MADE TO GOING FORECAST THE REST OF TONIGHT
WAS TO BOOST UP CLOUD COVER. HIGH AND EVEN A FEW MID CLOUDS
ASSOCIATED WITH A SHEARED OUT SHORTWAVE AND VERY ELEVATED /500MB+/
AXIS OF MOIST RETURN CONTINUE TO STREAM ENE INTO THE AREA. THE
REMNANT SHORT WAVE CIRCULATION IS SEEN ACROSS SE IA ON VISIBLE AND
IR. THE OVERALL COVERAGE OF CLOUDS LOOKS LIKE IT HAS FADED IN THE
PAST HOUR AND RAP FORECAST RH CONTINUES THIS GRADUAL DIMINISHING
TREND AS THE AREA COMES ACROSS. SATELLITE ALONG WITH VISUAL
OBSERVATION OUT THE WINDOW WOULD INDICATE HOWEVER WE WOULD STILL
BE DEALING WITH A PARTLY CLOUDY SKY FOR A WHILE. SO HAVE BOOSTED
CLOUD COVER UP SOME. WHILE THE SURFACE RIDGE AXIS REMAINS ACROSS
MI INTO NE IL...THESE CLOUDS MAY BEGIN TO STUNT THE TEMPERATURE
DROP SOME. GOING MINS STILL LOOK ALRIGHT THOUGH AND IN LINE WITH
18Z GUIDANCE. IF CLOUDS LINGER THROUGH THE ENTIRE OVERNIGHT ITS
LIKELY MINS WILL BE 3-5 DEGREES WARMER. IT IS ALWAYS A CHALLENGE
TO PREDICT 15000 FT AND HIGHER CLOUD BEHAVIOR...BUT WILL NOT
COMPLAIN THAT IS THE ONLY REAL FORECAST CHALLENGE TONIGHT.
MTF
//PREV DISCUSSION...
322 PM CDT
MAIN FORECAST CONCERNS/CHALLENGES ARE WITH PRECIP TRENDS OVER THE
NEXT SEVERAL DAYS WITH THUNDERSTORM CHANCES INTO THE WEEKEND...AS
WELL AS A WARMER AND MORE MOIST ENVIRONMENT SETTLING INTO THE AREA
BEGINNING AS EARLY AS TOMORROW.
QUIET AND PLEASANT CONDITIONS IN PLACE ACROSS THE AREA THIS
AFTERNOON AS HIGH PRESSURE SPANS MUCH OF THE REGION. PARTLY
CLOUDY/SUNNY SKIES AND TEMPS GENERALLY IN THE 70S...EXCEPT FOR 60S
NEAR THE LAKE...AS WELL AS LOWER DEWPOINT AIR IN PLACE HAVE
PROVIDED THESE PLEASANT CONDITIONS. ALTHOUGH A SIGN TO COME OF A
WARMER AIRMASS DEFINITELY MOVING UP ACROSS THE REGION ARE WITH THE
LOW/MID 80S TEMPS DRAWING CLOSE TO THE SOUTHERN CWA THIS
AFTERNOON...AS LOW LEVEL WIND FIELD ALREADY TRYING TO FLOP OVER TO
MORE OF A SOUTHERLY DIRECTION. A TREND TOWARDS ABOVE NORMAL TEMPS
WILL OCCUR OVER THE NEXT SEVERAL DAYS INITIALLY FOR AREAS AWAY
FROM THE LAKE TOMORROW BUT WITH THIS TREND EXTENDING TOWARDS AREAS
NEAR THE LAKE BY FRIDAY AS SOUTHERLY WINDS LOOK TO BE IN
PLACE...AND ALSO REMAIN IN PLACE.
DESPITE CURRENT HIGH PRESSURE BEGINNING TO SLOWLY DRIFT EAST OF
THE AREA TONIGHT...QUIET WEATHER WITH MOSTLY CLEAR SKIES WILL BE
OBSERVED ONCE AGAIN WITH NIGHT TIME LOWS DIPPING DOWN TO THE
MID/UPPER 50S FOR MOST AREAS AND EVEN STAYING IN THE LOWER 60S
ACROSS THE SOUTHERN CWA. WITH THIS HIGH CONTINUING TO SLOWLY SHIFT
EAST ON THURSDAY...IT DOES APPEAR AS IF MOST OF THE DAY WILL
REMAIN DRY ACROSS THE CWA. ALTHOUGH...GUIDANCE IS HINTING AT THE
POSSIBILITY FOR SOME CONVECTIVE ACTIVITY IN THE AFTERNOON
PRIMARILY OVER NORTHERN/NORTHWEST ILLINOIS AND CANT COMPLETELY
RULE IT OUT AT THIS TIME. CURRENT UPSTREAM MID LEVEL TROUGH OVER
THE CENTRAL PLAINS WILL WORK ITS WAY EAST TOWARDS THE CWA ON
THURSDAY WITH FORECAST SOUNDINGS INDICATING SOME MOISTENING OF THE
COLUMN...AS SOUTHERLY FLOW AIDS IN THE RETURN OF THIS MORE MOIST
ENVIRONMENT. AS WEAK FORCING MOVES OVER NORTHERN ILLINOIS WITH THE
APPROACH OF THIS WAVE WHILE WEAK INSTABILITY ALSO SETTLES BACK IN
ACROSS THE CWA WITH MINIMAL CIN BY THE AFTERNOON...COULD SEE AT
LEAST ISOLATED SHOWERS/THUNDERSTORMS THURSDAY AFTERNOON WORTHY OF
SLIGHT CHANCE POPS AT THIS TIME.
ALTHOUGH THE CURRENT NAM IS INDICATING CONVECTION REMAINING
OVERHEAD THROUGH THURSDAY EVENING...DO FEEL AS IF IT IS A BIT
BULLISH. THE MAJORITY OF ANY CONVECTION ON THURSDAY SHOULD BE
DIURNALLY DRIVEN WITH A DIMINISHING TREND THEN EXPECTED INTO THE
EVENING...AS THE FOCUS OF MORE WIDESPREAD DEVELOPMENT TO REMAIN
WELL TO THE NORTH OF THE CWA MORE TOWARDS THE STRONGER WESTERLIES
AND LLJ FOCUS. STILL...PERSISTENT WAA ALONG AND JUST WEST OF THE
CWA COULD HELP STEER SOME LINGERING SHOWERS/THUNDERSTORMS ACROSS
NORTHWEST ILLINOIS AND HAVE MAINTAINED THE CURRENT SLIGHT CHANCE
POPS FOR THE FAR NORTHWEST TIER OF COUNTIES LATE THURSDAY NIGHT.
AS A STRONGER WAVE/WAA MOVE ACROSS THE REGION ON FRIDAY...SHOULD
OBSERVE BETTER CHANCES FOR SHOWERS/THUNDERSTORMS ESPECIALLY INTO
THE AFTERNOON. OVERALL WEAK FLOW ALOFT IS EXPECTED ACROSS THE CWA
ON FRIDAY WITH THE STRONGER WESTERLIES ONCE AGAIN REMAINING JUST
TO THE NORTH. ALTHOUGH...WITH INSTABILITY/MOISTURE REALLY
INCREASING DURING THE PERIOD...WILL NEED TO MONITOR THE POTENTIAL
FOR STRONG THUNDERSTORMS TO DEVELOP FRIDAY AFTERNOON. CONFIDENCE
BEGINS TO LOWER FRIDAY NIGHT INTO THE WEEKEND WITH OVERALL
CONVECTIVE TRENDS. ALTHOUGH IT DOES APPEAR THAT THERE WILL REMAIN
CHANCES FOR SHOWERS/THUNDERSTORMS INTO THE CWA ESPECIALLY AS A
MOIST AND UNSTABLE ENVIRONMENT SETTLES IN BUT WITH A MORE FAVORED
LOCATION TO BE ACROSS THE NORTHERN HALF OF THE CWA...AS THE AREA
WILL BE CLOSER TO STRONGER WESTERLIES/PASSING MID LEVEL FEATURES.
RODRIGUEZ
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 06Z...
* LAKE BREEZE THURSDAY AFTERNOON.
* POTENTIAL FOR CONVECTION ALONG THE LAKE BREEZE.
BMD
//DISCUSSION...UPDATED 06Z...
MOST OF THE FORECAST SHOULD BE QUIET AS HIGH PRESSURE CONTINUES TO
DOMINATE THE AREA. THE HIGH OFF TO OUR EAST WILL CONTINUE TO SETTLE
SOUTHEAST OVER THE MID ATLANTIC COAST WITH EASTERLY WINDS OVERNIGHT
FAVORING A MORE SOUTHERLY DIRECTION THURSDAY. THE EXCEPTION WILL BE
AT ORD/MDW WHERE A LAKE BREEZE MAY TURN WINDS BACK TO THE SOUTHEAST
THURSDAY AFTERNOON AND EVENING. MODELS INDICATE MODERATE INSTABILITY
DEVELOPING THURSDAY AFTERNOON WITH LITTLE CAPPING. THERE MAY BE A
FEW SHOWERS OR THUNDERSTORMS THAT DEVELOP ALONG THE LAKE BREEZE
BOUNDARY AND THEN DRIFT EAST OVER LAKE MICHIGAN. THAT SAID...THE
CONVERGENCE ALONG THE FRONT WILL BE SOMEWHAT WEAK LEADING TO LITTLE
CONFIDENCE IN THIS SCENARIO PANNING OUT. THE POTENTIAL IS TOO LOW AT
THIS TIME FOR MENTION IN THE TAF.
BMD
//ORD AND MDW CONFIDENCE...UPDATED 06Z...
* MEDIUM CONFIDENCE IN WIND TRENDS.
* LOW CONFIDENCE IN SHRA/TSRA THURSDAY AFTERNOON.
* HIGH CONFIDENCE IN REMAINING FORECAST ELEMENTS.
BMD
//OUTLOOK FOR ORD/MDW FOR 12Z FRIDAY-12Z WEDNESDAY...UPDATED 00Z...
FRIDAY THROUGH TUESDAY...PERIODIC CHANCES FOR TSRA...ELSE VFR.
ZEBIC
&&
.MARINE...
210 PM CDT
A LARGE AREA OF HIGH PRESSURE CENTERED OVER THE EASTERN GREAT
LAKES EXTENDS FROM SOUTHERN QUEBEC TO THE LOWER OHIO VALLEY AND
FROM THE UPPER MISSISSIPPI VALLEY TO NEW ENGLAND AND THE MID
ATLANTIC REGION. THE HIGH PRESSURE WILL GRADUALLY SLIDE TO THE
EAST AS A TROUGH OF LOW PRESSURE DEVELOPS OVER THE CENTRAL PLAINS.
WHILE THE HIGH PRESSURE WILL DOMINATES LAKE MICHIGAN THROUGH
FRIDAY...RELATIVELY LIGHT WINDS WILL PREVAIL OVER THE OPEN WATERS
AND LAKE BREEZE OR ONSHORE FLOW WILL PREVAIL FOR THE IL/IN
NEARSHORE WATERS THROUGH FRIDAY. A SFC LOW WILL DROP OUT OF THE
NORTHERN ROCKIES AND TRACK EWD TO LAKE SUPERIOR BY FRIDAY
EVENING. ANOTHER LOW WILL DEVELOP OVER ERN KANSAS ON THURSDAY AS
THE HIGH SLIDES OFF THE MID ATLANTIC COAST. THROUGH THIS
PERIOD...SOUTHERLY FLOW WILL REESTABLISH OVER LAKE MICHIGAN AND BE
THE PREVAILING CONDITION OVER THE LAKE THROUGH EARLY NEXT WEEK.
KREIN
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...NONE.
&&
$$
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AREA FORECAST DISCUSSION
NWS DES MOINES IA
1205 AM CDT THU JUN 20 2013
.UPDATE...
ISSUED AT 937 PM CDT WED JUN 19 2013
HAVE LOWERED POPS THIS EVENING WITH NOTHING OF NOTE IN SATELLITE
IMAGERY AFTER DIURNAL LOSS OF CU. WEAK LIFT ASSOCIATED WITH
ELONGATED MN/IA/MO SHORT WAVE AXIS IS PRODUCING NOTHING BEYOND BKN
MID/HIGH CLOUDS AND EXITING THE FORECAST AREA. RAP OBJECTIVE
ANALYSIS DOES SHOW THETA-E ADVECTION THROUGH THE MO VALLEY...BUT
MOISTURE MUST BE LIMITED FOR NOW AS SKIES ARE MOSTLY CLEAR. WARM
ADVECTION DOES CONTINUE OVERNIGHT SO GRADUALLY RE-INTRODUCED POPS
WEST AND NORTH LATE IN CASE THIS THERMODYNAMIC FORCING EVENTUALLY
MATURES AND IS REALIZED.
&&
.SHORT TERM.../TONIGHT/...
ISSUED AT 413 PM CDT WED JUN 19 2013
MAIN FORECAST CONCERN IS WITH SMALL CHANCES OF ISOLATED STORMS
ACROSS THE WEST AND NORTH THIS AFTERNOON THROUGH THURSDAY MORNING.
LEANED TOWARD A BLEND OF THE HI-RES MODELS FOR TRENDS TONIGHT INTO
THURSDAY MORNING.
THE ARW-WEST AND LATEST HRRR HAVE SOME ISOLATED THUNDERSTORMS
DEVELOPING THIS AFTERNOON INTO THE EARLY EVENING ACROSS WESTERN TO
NORTHERN PORTIONS OF THE FORECAST AREA. CAP SEEMS TO BE WINNING ATTM
AND CUT BACK ON POPS TO MAINLY THE FAR WEST EVEN THOUGH SURFACE
BASED CAPE AROUND 1000-1500 J/KG WITH MUCAPE SLIGHTLY HIGHER. THERE
IS VERY LITTLE...IF ANY SHEAR PRESENT THROUGH THE EVENING HOURS..SO
NOT ANTICIPATING ANYTHING LONG-LIVED. WEAK THETA-E ADVECTION MOVES
INTO WESTERN IOWA PAST 06Z AS A BROAD AREA OF VORTICITY CUTS THROUGH
THE REGION TONIGHT. TRANSITIONED CHANCE POPS FURTHER EAST OVERNIGHT
AND MAINLY KEPT HIGHEST POPS ACROSS NORTHERN IOWA PAST 06Z THURSDAY
WHERE BEST FORCING IS PRESENT.
.LONG TERM.../THURSDAY THROUGH WEDNESDAY/...
ISSUED AT 413 PM CDT WED JUN 19 2013
UPPER LEVEL LOW CONTINUES SLOWLY MOVE OVER THE PACIFIC NORTHWEST
TODAY AND WILL MOVE LITTLE THROUGH SATURDAY BEFORE BEGINNING TO
LIFT NORTHEAST INTO CANADA ON SUNDAY. WEAK RIDGING OVER IOWA WILL
SLOWLY SHIFT EAST DURING THIS TIME AS WELL AND WILL FOCUS
SOUTHWEST FLOW INTO THE UPPER MIDWEST. NUMEROUS SHORT WAVES ARE
STILL EXPECTED TO RIPPLE THROUGH THIS FLOW AND IMPACT MAINLY
NORTHERN IOWA AND AREAS TO THE NORTH DURING THE PERIOD WHILE WARM
AIR ALOFT DRIVES A CAP INTO CENTRAL AND SOUTHERN IOWA FRIDAY INTO
SATURDAY.
SURFACE LOW PRESSURE WILL LIFT NORTH THROUGH KANSAS AND NEBRASKA
THURSDAY AND THURSDAY NIGHT WITH A SECONDARY WARM FRONT MOVING
NORTH THROUGH THE STATE. WHILE THE PRIMARY FRONTAL BOUNDARY WILL
BE NORTH INTO MINNESOTA DURING THE AFTERNOON...THE POTENTIAL FOR
THE SECONDARY BOUNDARY TO LIFT INTO WEST CENTRAL DURING THE
AFTERNOON. SOME MIXED LAYER CIN WILL BE IN PLACE THROUGH A WEAK
SHORT WAVE IS EXPECTED TO MOVE ACROSS THE AREA WITH MID LEVEL
COOLING THAT MAY BE ENOUGH TO KICK OFF A FEW STORMS. IF STORMS
FIRE...CERTAINLY A FEW SUPERCELLS WOULD BE POSSIBLE. STILL SOME
HINTS THAT A DAKOTAS MCS COULD DROP INTO NORTHERN IOWA THURSDAY
NIGHT AND COULD BRING AN ADDITIONAL CHANCE FOR SEVERE WEATHER.
MUCH OF THE AREA OVER THE CENTRAL AND SOUTH BECOMES CAPPED FRIDAY
INTO THE WEEKEND AND HAVE BEGUN TO DROP POPS ACROSS THESE AREAS
WITH THE PRIMARY FOCUS BEING ACROSS THE NORTH. A VERY WARM AND
HUMID AIR MASS WILL LIFT INTO THE AREA WITH HIGH TEMPERATURES IN
HIGHS IN THE UPPER 80S TO MID 90S AND DEWPOINTS RISING INTO THE
70S. THE SUBTROPICAL HIGH CONTINUES TO EXERT ITSELF OVER THE
SOUTHERN PLAINS INTO EARLY NEXT WEEK AND BUILDING NORTH. THE RING
OF FIRE MAY CLIP INTO NORTHERN IOWA DURING END OF THE PERIOD BY
THE PRIMARY FOCUS WILL BE TO THE NORTH WITH SUMMER IN PLACE OVER
IOWA.
&&
.AVIATION...20/06Z
ISSUED AT 1204 AM CDT THU JUN 20 2013
VFR CONDITIONS STATEWIDE AT 06Z WITH NOTHING MORE THAN SCT
MID/HIGH CLOUDS EAST. THERE IS SOME CONCERN THAN MVFR VSBYS MAY
BRIEFLY DEVELOP BEFORE DAYBREAK...BUT NOT ENOUGH TO INCLUDE AT THE
MOMENT WITH SELY WINDS NOT DECOUPLING. VARIOUS MODELS AND
ENSEMBLES SHOW CHANCES FOR CONVECTION FROM THE AFTERNOON INTO THE
EVENING...BUT CONFIDENCE IN LOCATION AND TIMING IS NOT THERE TO
INCLUDE YET. OPTED FOR NO MENTION RATHER THAN 18 HOUR VCSH BROAD
BRUSH.
&&
.DMX WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
UPDATE...SMALL
SHORT TERM...PODRAZIK
LONG TERM...DONAVON
AVIATION...SMALL
AREA FORECAST DISCUSSION
NWS GOODLAND KS
539 PM MDT FRI JUN 21 2013
.SHORT TERM...(THIS EVENING THROUGH SATURDAY)
ISSUED AT 216 PM MDT FRI JUN 21 2013
AS OF 3 PM CDT...2 PM MDT...SKIES ACROSS THE TRI-STATE WERE CLEAR
ALBEIT A LITTLE HAZY FROM SMOKE THAT CONTINUES TO STREAM IN FROM
FIRES IN SOUTH CENTRAL COLORADO. SOME CUMULUS AND TOWERING CUMULUS
COULD BE SEEN ON VISIBLE SATELLITE IMAGERY JUST NORTH OF
AKRON...COLORADO. SOUTH WINDS HAVE PICKED UP MAINLY EAST OF A LINE
FROM TRENTON...NEBRASKA TO COLBY AND LEOTI KANSAS AS A SURFACE LOW
PRESSURE SYSTEM DEEPENS TO THE WEST. TEMPERATURES RANGED FROM THE LOW
90S IN EAST COLORADO TO NEAR 100 ACROSS SOME PARTS OF KANSAS AND
SOUTHWEST NEBRASKA. VERY DRY AIR WAS ALSO STARTING TO MOVE IN FROM
THE SOUTHWEST.
SIMILAR TO YESTERDAY...ISOLATED THUNDERSTORMS ARE EXPECTED TO
DEVELOP ALONG A DRYLINE. SURFACE CONVERGENCE IS BEGINNING TO APPEAR
IN THE SURFACE WIND FIELD ALONG THE DRYLINE WHICH WILL BE THE FOCUS
OF STORM DEVELOPMENT. THE HRRR AND NAM MODELS SUGGEST STORM
INITIATION WILL OCCUR IN FAR WESTERN KANSAS. STORMS SHOULD BE
CONFINED MAINLY ALONG AND EAST OF A LINE FROM YUMA COLORADO TO
GOODLAND KANSAS TO TRIBUNE KANSAS AND WEST OF A LINE FROM MCCOOK
NEBRASKA TO RUSSELL SPRINGS KANSAS. ANY STORM THAT IS ABLE TO
DEVELOP WILL BE STRONG TO SEVERE WITH LARGE HAIL AND DAMAGING WINDS
AS THE MAIN THREATS.
FOR TONIGHT...GUSTY WINDS WILL CONTINUE A LOW LEVEL JET DEVELOPS
OVER THE EASTERN HALF. WINDS SHOULD BE BELOW WIND ADVISORY CRITERIA
WITH THE STRONGEST WINDS REMAINING TO THE SOUTH OVER SOUTHWEST AND
SOUTH CENTRAL KANSAS. LOWS WILL STRUGGLE TO FALL TONIGHT WITH THE
ATMOSPHERE IN A MIXED STATE SO HAVE GONE ABOVE GUIDANCE FOR LOWS.
TONIGHTS TEMPERATURE FORECAST IS VERY SIMILAR TO WHAT ACTUALLY
OCCURRED LAST NIGHT.
FOR TOMORROW...A REPEAT OF TODAY IS EXPECTED FOR THE MOST PART.
TEMPERATURES ARE NOT EXPECTED TO BE AS HOT AS TODAY WITH HIGHS ONLY
REACHING THE MID TO UPPER 90S WITH A FEW SPOTS REACHING 100. A WEAK
FRONT WILL MOVE INTO THE AREA FROM THE NORTH...RESULTING IN MAINLY A
WIND SHIFT WITH EVER SO SLIGHTLY COOLER TEMPERATURES. WITH A DRYLINE
STILL IN PLACE...ISOLATED THUNDERSTORMS ARE POSSIBLE AGAIN FOR
TOMORROW. ANY STORMS THAT ARE ABLE TO DEVELOP WOULD LIKELY BECOME
SEVERE. THERE IS A SLIGHT RISK FOR SEVERE WEATHER ACROSS SOUTHWEST
NEBRASKA TOMORROW AND THAT SEEMS REASONABLE GIVEN THE LOCATION OF
THE FRONT TOMORROW. THE FRONT SHOULD PROVIDE A BETTER FOCUS FOR
THUNDERSTORM DEVELOPMENT OVER THE NORTHERN THIRD OF THE FORECAST
AREA. GUSTY SOUTH WINDS ARE EXPECTED AGAIN WITH A LOW PRESSURE
DEEPENING TO THE WEST.
.LONG TERM...(SATURDAY NIGHT THROUGH FRIDAY)
ISSUED AT 215 PM MDT FRI JUN 21 2013
A SIGNIFICANT CHANGE IN THE UPPER PATTERN WILL TAKE PLACE DURING
THIS EXTENDED PERIOD. THE CURRENT SOUTHWEST FLOW ALOFT
ACCOMPANIED BY NUMEROUS MINOR DISTURBANCES WILL TRANSITION TO A
BUILDING UPPER RIDGE...STARTING OVER NM/AZ TUESDAY AND ULTIMATELY
ENCOMPASSING ALL OF THE CENTRAL ROCKIES BY THE END OF THE WEEK.
THERE STILL LOOKS TO BE A COUPLE OF OPPORTUNITIES FOR STORMS
COMING OUT OF COLORADO AND MOVING ACROSS THE CWA SATURDAY AND
SUNDAY EVENING AS WEAK SHORT WAVE TROUGHS MOVE THROUGH THE FLOW.
AFTER THAT...PRECIP POTENTIAL WILL DIMINISH AS THE UPPER RIDGE AND
WARMING MID-LEVEL TEMPS BEGIN TO DOMINATE.
TEMPERATURES ARE EXPECTED TO REMAIN WELL ABOVE NORMAL DURING THE
PERIOD WITH HIGHS MOSTLY IN THE MIDDLE 90S TO NEAR 100 AND LOWS IN
THE 60S TO NEAR 70.
CURRENT EXTENDED GUIDANCE BEYOND THIS PERIOD SUGGESTS THE UPPER
RIDGE WILL CONTINUE TO BUILD NORTH TOWARD IDAHO BY NEXT WEEKEND.
IF THAT PANS OUT...THE UPPER FLOW WILL BECOME NORTHWEST OVER THE
CWA POSSIBLY INCREASING THE CHANCE FOR LATE DAY STORMS MOVING
SOUTHEAST OFF THE CHEYENNE RIDGE.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z SATURDAY EVENING)
ISSUED AT 535 PM MDT FRI JUN 21 2013
VFR CONDITIONS ARE EXPECTED THROUGH THE NEXT 24 HOURS AT BOTH
GLD AND MCK. WIND FORECAST TOMORROW MORNING IS UNCERTAIN AT GLD
GIVEN VERY CLOSE PROXIMITY OF SURFACE TROUGH/WIND SHIFT. THERE
COULD BE A PERIOD IN THE MORNING OF A MORE WESTERLY OR
NORTHWESTERLY DIRECTION THAN WHAT THE TAF INDICATES.
&&
.FIRE WEATHER...
ISSUED AT 216 PM MDT FRI JUN 21 2013
CRITICAL FIRE WEATHER CONDITIONS ARE DEVELOPING TO THE
SOUTHWEST...MAINLY OVER GREELEY AND WALLACE COUNTIES KANSAS AND
CHEYENNE AND KIT CARSON COUNTIES IN COLORADO. EVEN THOUGH RED FLAG
CRITERIA WILL BE MET FOR THESE LOCATIONS TODAY FOR WIND AND RELATIVE
HUMIDITY...RECENT RAINFALL AND HIGHER FUEL MOISTURE CONTENT ARE
PREVENTING EXPLOSIVE FIRE WEATHER CONDITIONS FROM BECOMING A
PROBLEM. THEREFORE...HAVE OPTED NOT TO ISSUE A RED FLAG WARNING.
THE SAME STORY WILL REPEAT ITSELF AGAIN TOMORROW WITH LOW RELATIVE
HUMIDITIES FILTERING IN FROM THE SOUTHWEST AND WINDS INCREASING
BEHIND THE DRYLINE IN THE AFTERNOON. FUELS COULD BE MORE RIPE FOR
FIRE POTENTIAL TOMORROW AFTER A COUPLE HOT DAYS WITH LITTLE RAINFALL
BUT THINKING THAT FUEL MOISTURE WILL STILL BE HIGH ENOUGH THAT A RED
FLAG WARNING WILL NOT BE WARRANTED.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
SHORT TERM...RRH
LONG TERM...DLF
AVIATION...BRB
FIRE WEATHER...RRH
AREA FORECAST DISCUSSION
NWS TOPEKA KS
309 PM CDT THU JUN 20 2013
.SHORT TERM...(THIS EVENING THROUGH FRIDAY)
ISSUED AT 305 PM CDT THU JUN 20 2013
20Z WATER VAPOR SHOWS A CLOSED UPPER LOW OVER THE NORTHERN ROCKIES
AND PACIFIC NORTHWEST AND A SHORTWAVE ROUNDING AN UPPER RIDGE AND
MOVING INTO THE UPPER MIDWEST/GREAT LAKES REGION. SREF AND RAP
MODELS SHOW THE UPPER RIDGE OVER THE SOUTHERN PLAINS TO BE GRADUALLY
STRENGTHENING WITH HEIGHTS RISING OVER CENTRAL AND EASTERN KS. AT
THE SURFACE...OBS SHOW A TROUGH AXIS FROM THE SOUTHERN HIGHS PLAINS
NORTH INTO THE NORTHERN PLAINS. THIS HAS CAUSED A STRENGTHENING
SURFACE PRESSURE GRADIENT AND GUSTY SOUTH WINDS ACROSS THE REGION.
FOR TONIGHT AND FRIDAY...THE NAM HAS NOT SHOWN VERY GOOD PERFORMANCE
RECENTLY WITH ITS HANDLING OF CONVECTION. THE OTHER SOLUTIONS
INCLUDING THE GFS/ECMWF/GEM/ARW SUGGEST THAT WITH THE STRENGTHENING
UPPER LEVEL RIDGE ACROSS THE FORECAST AREA PRECIP WILL REMAIN NORTH
AND EAST OF THE FORECAST AREA THROUGH FRIDAY. SO WITH THIS IN MIND
HAVE OPTED TO IGNORE THE NAM SOLUTION AND THE QPF IT BRINGS THROUGH.
THERE DOES NOT APPEAR TO BE ANY STRONG FORCING IN THE FORM OF A
SHORTWAVE OR STRONG ISENTROPIC LIFT OVER THE AREA TO GENERATE
PRECIP...SO THE FORECAST WILL REMAIN DRY THROUGH FRIDAY. LOWS
TONIGHT SHOULD BE QUITE MILD WITH THE STRONG SURFACE PRESSURE
GRADIENT KEEPING WINDS UP THROUGH THE NIGHT. LOWS ARE EXPECTED TO BE
IN THE LOWER TO MID 70S. HIGHS FRIDAY LOOK TO BE RATHER SIMILAR TO
TODAYS BASED ON THE 850 TEMPS OF THE GFS/ECMWF/GEM. WITH THE BOUNDARY
LAYER MIXING TO AROUND 850MB...HIGHS SHOULD BE IN THE LOWER TO MID
90S. WINDS FRIDAY LOOK TO BE QUITE BREEZY ONCE AGAIN WITH THE STRONG
PRESSURE GRADIENT RIGHT OVER THE FORECAST AREA. CONSIDERED THE NEED
FOR A WIND ADVISORY FRIDAY AFTERNOON BUT DECIDED THE LIKELIHOOD OF
ADVISORY LEVEL WINDS WAS NOT HIGH ENOUGH FOR AN ADVISORY AT THIS
TIME. THE NAM IS THE ONLY MODEL THAT HAS A REALLY STRONG PRESSURE
GRADIENT AND SUSTAINED WINDS AROUND 30MPH. SO GIVEN ITS RECENT
TRACK RECORD OVER THE LAST DAY OR TWO...DO NOT FEEL COMFORTABLE
PUTTING MUCH STOCK INTO IT. LATER SHIFTS CAN REEVALUATE.
.LONG TERM...(FRIDAY NIGHT THROUGH THURSDAY)
ISSUED AT 305 PM CDT THU JUN 20 2013
FRIDAY NIGHT THROUGH SUNDAY...
FRIDAY NIGHT A FRONTAL BOUNDARY IS EXPECTED TO MOVE INTO NORTHERN
NEBRASKA AND NORTHEAST COLORADO. THUNDERSTORMS MAY DEVELOP ALONG THE
BOUNDARY IN NEBRASKA...BUT ARE EXPECTED TO REMAIN WELL TO THE NORTH
OF THE CWA. THERMAL RIDGE WILL REMAIN IN PLACE ON SATURDAY ACROSS
THE CENTRAL PLAINS. THE UPPER RIDGE OVER THE CENTRAL PLAINS WILL
BREAKDOWN AS A SHORTWAVE TROUGH MOVES ACROSS THE NORTHERN ROCKIES
AND NORTHERN PLAINS. THE FRONTAL BOUNDARY WILL SLIDE A LITTLE
FURTHER SOUTHEAST SATURDAY NIGHT AND SUNDAY. SOME SCATTERED
THUNDERSTORMS ARE POSSIBLE ALONG THE FRONT IN NEBRASKA AND COULD
AFFECT THE NORTHERN CWA. BETTER FORCING WILL REMAIN TO THE NORTH OF
THE CWA. TEMPERATURES WILL REMAIN ON THE HOT SIDE WITH HIGHS IN THE
90S SATURDAY AND SUNDAY. LOWS IN THE LOWER TO MIDDLE 70S ARE
EXPECTED. HEAT INDICES IN THE UPPER 90S TO LOW 100S ARE POSSIBLE
EACH DAY.
SUNDAY NIGHT THROUGH THURSDAY...
ON SUNDAY THE MAIN SHORTWAVE TROUGH WILL BE LIFTING NORTHEAST
THROUGH THE NORTHERN PLAINS WHILE THE TRAILING FRONT PUSHES SOUTH
INTO EASTERN NEBRASKA AND WESTERN KANSAS. MEANWHILE AN EMBEDDED
SHORTWAVE IN THE SOUTHWEST FLOW WILL SLIDE ACROSS THE REGION
AIDING IN THUNDERSTORM DEVELOPMENT ALONG AND NEAR THE SFC FRONT.
IT DOES APPEAR THAT THE BETTER CHANCES FOR STORMS WILL BE ACROSS
AREAS NORTH OF INTERSTATE 70 SUNDAY NIGHT. AN UPPER LEVEL RIDGE
WILL THEN BUILD OVER THE PLAINS CAUSING HIGH TEMPERATURES TO REACH
THE MID TO UPPER 90S WITH HEAT INDICES IN THE LOW 100S MONDAY
THROUGH THE PERIOD. THE RIDGE WILL CONTINUE TO BUILD MORE ACROSS
THE WESTERN US WHICH WILL ALLOW THE LONGWAVE TROUGH TO DIG SOUTH
ACROSS THE EASTERN US. THIS WILL BRING A FRONT INTO THE REGION ON
WEDNESDAY AND THURSDAY INCREASES CHANCES FOR PRECIP.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z FRIDAY AFTERNOON)
ISSUED AT 1231 PM CDT THU JUN 20 2013
THERE IS NO OBVIOUS WAVE SEE IN WATER VAPOR AND THE BOUNDARY LAYER
WILL REMAINED MIXED OUT SO THERE SHOULD NOT BE A SURFACE FEATURE
TO LIFT A PARCEL. SO WITH MODELS SHOWING HEIGHT RISES THROUGH THE
NEXT 24 HOURS AND THE NAM HAVING DONE A POOR JOB WITH CONVECTION
RECENTLY...WILL KEEP THE TERMINALS DRY AND FOLLOW THE RAP AND GFS
SOLUTIONS. THERE IS AN OUTSIDE CHANCE FOR SOME LLWS AS THE LOW
LEVEL JET INCREASES OVERNIGHT. HOWEVER FORECAST SOUNDINGS DO NOT
SHOW A VERY SHARP NOCTURNAL INVERSION AND SURFACE WINDS ARE
EXPECTED TO REMAIN ABOVE 10KTS. SO HAVE NOT INCLUDED LLWS JUST
YET.
&&
.TOP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...WOLTERS
LONG TERM...SANDERS/WOYNICK
AVIATION...WOLTERS
AREA FORECAST DISCUSSION
NWS WICHITA KS
1231 PM CDT THU JUN 20 2013
.SHORT TERM...(TODAY THROUGH FRIDAY)
ISSUED AT 332 AM CDT THU JUN 20 2013
MOISTURE INITIALIZATION CONTINUES TO BE VERY POOR AMONG MOST MODELS.
BOTH 00Z GFS/NAM GENERATED FICTITIOUS DEWPOINT GRADIENTS THAT
INFLUENCED CONVECTIVE DEVELOPMENT. THE 0000 UTC ECMWF WAS NOT TOO
BAD...AND THE HRRR WAS BETTER AND HAS BEEN PERSISTENT IN
DEVELOPING PRECIPITATION OVER FLINT HILLS TOWARDS DAYBREAK. SOME
RELATIVELY FLAT ALTOCUMULUS WAS EVIDENT VISUALLY AROUND SUNSET...
AND THIS MAY BE ONLY CHANCE FOR PRECIPITATION THIS MORNING. 0000
UTC UPPER AIR ANALYSIS SUGGEST WEAK TROUGH MOVING THROUGH AT THIS
TIME...SO DEVELOPMENT IMMEDIATELY UPSTREAM IS UNLIKELY. WITH
INCREASING PRESSURE GRADIENT AND GOOD MIXING...GUSTY WINDS ARE
LIKELY BY MIDDAY AND COULD SEE SPEEDS FLIRTING WITH ADVISORY
CRITERIA IN THE FAVORED AREAS OF CENTRAL KS. GIVEN IT APPEARS
MARGINAL AT THE MOMENT...WILL HOLD OFF ON HEADLINES. CHANCES FOR
PRECIPITATION LOOK SLIM BY AFTERNOON/EVENING WITH INCREASING
TEMPERATURES ALOFT.
WHILE POSSIBLE THAT PRECIPITATION COULD DEVELOP UPSTREAM THU
NIGHT/EARLY FRI...ODDS LOOK TOO LOW TO MENTION AT THIS TIME.
TEMPERATURES ON FRI WILL CONTINUE TO CLIMB WITH WARM/WINDY
CONDITIONS DURING THE DAY. -HOWERTON
.LONG TERM...(SATURDAY THROUGH WEDNESDAY)
ISSUED AT 332 AM CDT THU JUN 20 2013
SAT-SUN:
SHORTWAVE MAY EDGE FRONT CLOSE ENOUGH TO SPREAD PRECIPITATION
INTO FAR NORTHWESTERN SECTIONS SUN NIGHT...BUT NOT VERY
OPTIMISTIC. PROXIMITY OF FRONT WILL LIKELY ONLY HAD MORE HEAT TO
THE WARMUP.
FOR MON-WED:
WILL CONTINUE THE DRY AND WARM FORECAST THROUGH AT LEAST
TUE...HOWEVER BOTH GFS/ECMWF HINTING AT A BREAKDOWN OF THE UPPER
RIDGE BY WED. NOT PARTICULARLY OPTIMISTIC ABOUT THIS BUT DID GO
ALONG WITH A DEGREE OR TWO COOLER IN THE NORTH PER CONSENSUS.
ISOLATED STORMS CANNOT BE RULED OUT WITH PEAK HEATING...BUT ODDS
ARE TOO LOW TO MENTION. -HOWERTON
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z FRIDAY AFTERNOON)
ISSUED AT 1225 PM CDT THU JUN 20 2013
THE MAIN AVIATION FORECAST CONCERN IS THE GUSTY SOUTHERLY WINDS
THROUGH THE PERIOD.
SOUTHERLY WINDS WILL REMAIN GUSTY THIS AFTERNOON AND EVEN MORE
THAN USUAL DURING THE NOCTURNAL HOURS. HAVE KEPT GUSTS TO NEAR 25
KTS OVERNIGHT AT MANY OF THE TERMINALS.
GUSTY SOUTH WINDS WERE A BIT STRONGER...EARLIER IN THE DAY
TODAY...WITH GUSTS ALREADY IMPACTING THE AREA AT 13Z. BECAUSE OF
THIS AND SIMILAR CONDITIONS TOMORROW...HAVE INCREASED WINDS AFTER
NOCTURNAL WEAKENING AT 13Z TOMORROW MORNING. THINK THE 26 KT WIND
ADVISORY CRITERIA COULD BE MET TOMORROW AFTERNOON...BUT CURRENT
FORECAST REMAINS SLIGHTLY SHY OF THE 26 KT SUSTAINED AT THIS
TIME.
BILLINGS
&&
.PRELIMINARY POINT TEMPS/POPS...
WICHITA-KICT 92 73 93 73 / 20 10 10 10
HUTCHINSON 94 73 95 73 / 20 10 10 10
NEWTON 94 72 94 72 / 20 10 10 10
ELDORADO 91 73 92 73 / 20 10 10 10
WINFIELD-KWLD 91 73 93 73 / 20 10 10 10
RUSSELL 98 73 98 73 / 10 10 10 10
GREAT BEND 96 72 97 72 / 10 10 10 10
SALINA 95 74 96 74 / 20 10 10 10
MCPHERSON 95 73 96 73 / 20 10 10 10
COFFEYVILLE 90 73 92 72 / 20 10 10 10
CHANUTE 88 72 91 71 / 30 10 10 10
IOLA 88 72 91 71 / 30 10 10 10
PARSONS-KPPF 89 73 91 72 / 30 10 10 10
&&
.ICT WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS TOPEKA KS
1024 AM CDT THU JUN 20 2013
.UPDATE...
ISSUED AT 1024 AM CDT THU JUN 20 2013
THE CONVECTION HAS NOT PANNED OUT AS THE PREV FORECAST EXPECTED.
LATEST WATER VAPOR AND RAP ANALYSIS SHOWS MID LEVEL HEIGHT RISES
WITH NO OBVIOUS WAVE UP STREAM. BECAUSE OF THIS HAVE LOWERED POPS
FOR THE REMAINDER OF THE DAY. WILL KEEP A SLIGHT CHANCE OF STORMS
SINCE THERE IS SOME WEAK ECHOS ALOFT IN SOUTH CENTRAL KS WITH
REASONABLE STEEP MID LEVEL LAPSE RATES. OTHERWISE THINK TODAY WILL
GENERALLY BE DRY. BECAUSE OF THIS AND WITH GOOD INSOLATION...HIGHS
ACROSS EASTERN KS ARE LIKELY TO BE WARMER THAN THE MID TO UPPER
80S. WITH THE RAP MIXING THE BOUNDARY LAYER TO AROUND
825MB...HIGHS LOOK TO BE AT LEAST AROUND 90 AND POTENTIALLY A FEW
DEGREES WARMER.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 423 AM CDT THU JUN 20 2013
COMPLICATED FORECAST IN STORE FOR THE AREA ON THURSDAY...MAINLY DUE
TO CONFLICTING SIGNALS BETWEEN MODEL GUIDANCE AND OBSERVATIONS.
CURRENTLY ACROSS THE AREA AN AREA OF SURFACE LOW PRESSURE HAS FORMED
OUT NEAR THE FRONT RANGE...WHICH HAS CAUSED SOUTHERLY FLOW TO
COMMENCE ACROSS THE AREA. EXPECT THIS FLOW TO INCREASE THROUGH THE
DAY AS THE PRESSURE GRADIENT TIGHTENS AND MIXING ALLOWS LOW LEVEL
FLOW TO TRANSLATE TO THE SURFACE. EXPECT THE MID LEVEL RIDGE TO
BECOME FIRMLY PLANTED OVER THE SOUTHERN PLAINS...WITH THE AMPLIFIED
APEX OF THE RIDGE AXIS EXTENDING NORTHWARD THROUGH CENTRAL KANSAS
AND THROUGH THE NORTHERN PLAINS. THE FIRST COMPLICATION IN THIS
FORECAST...REGARDING POPS FOR THE EARLY MORNING HOURS IS THE FACT
THAT MOST SHORT TERM HI-RES CONVECTIVE ALLOWING MODELS SHOW
ELEVATED CONVECTION OCCURRING ACROSS FAR EASTERN KANSAS OVER THE
NEXT FEW HOURS...HOWEVER CONSIDERING STORMS WOULD LIKELY FIRE
SHORTLY ACCORDING TO THE MODELS VIRTUALLY NO IR IMAGERY CLOUD
COOLING IS TAKING PLACE...WHICH WOULD INDICATE THAT CONVECTION IS
NOT OCCURRING...AT LEAST AS OF YET. FURTHER ENHANCING DOUBT IN THE
SHORT RANGE MODELS IS THE FACT THAT THEY CURRENTLY INDICATE A WEAK
MCS OVER NW OKLAHOMA...WHICH CURRENTLY DOES NOT EXIST. IR IMAGERY
IN FACT SHOWS CLOUD TOP WARMING INSTEAD OF COOLING INDICATIVE OF
CONVECTIVE PROCESSES OCCURRING. WILL CONTINUE TO MONITOR THE TRENDS
OVER THE NEXT COUPLE OF HOURS TO DETERMINE IF THE MORNING CONVECTION
WILL TAKE PLACE OVER THE EASTERN HALF OF THE FORECAST AREA.
THE FOCUS THEN TURNS TO THE AFTERNOON AND ANY CONVECTIVE CHANCES FOR
THAT TIME PERIOD. AGAIN...CONFLICTING SIGNALS MAKE THIS FORECAST
DIFFICULT...NAMELY THE FACT THAT NAM AND GFS BREAK OUT CONVECTION
LATER THIS AFTERNOON WITHIN THE DEEP WARM SECTOR. HOWEVER...MODEL
SOUNDINGS TAKEN ACROSS THE AREA FOR THIS WEEKEND ARE NOT SUPPORTIVE
OF CONVECTION OCCURRING...AS A LAYER OF WARM AIR AT 850 TO 700 MB
BECOMES IN PLACE OVER THE AREA THIS AFTERNOON. REGARDLESS OF THIS
SIGNAL NAM/GFS INDICATE SOME AFTERNOON CONVECTION TAKING PLACE OVER
THE AREA...WHICH IN THE ABSENCE OF STRONG MID LEVEL SUPPORT OR ANY
REAL LOW LEVEL CONVERGENCE SEEMS UNLIKELY TO OCCUR. THE ONE CAVEAT
TO THIS IS THAT LOW LEVEL BOUNDARIES...WHICH CURRENTLY DO NOT EXIST
MAY INFLUENCE AFTERNOON CONVECTION. SHOULD MORNING CONVECTION TAKE
PLACE IN THE AREA...IT COULD ENHANCE LOW LEVEL LIFT BY CREATING AN
OUTFLOW...WHICH MAY BRING STORMS LATER THIS AFTERNOON. CONSIDERING
THE SIGNALS IN PLACE RIGHT NOW...WILL OPT FOR A DRY AFTERNOON
FORECAST...BUT THE DAY SHIFT WILL NEED TO MONITOR AND ADJUST SHOULD
IT BECOME CLEARER THAT CONVECTION MAY OCCUR.
JL
.LONG TERM...(FRIDAY THROUGH WEDNESDAY)
ISSUED AT 423 AM CDT THU JUN 20 2013
A LONGER WAVE LENGTH UPPER LEVEL TROUGH WILL REMAIN ACROSS THE WEST
CENTRAL CONUS THROUGH SATURDAY NIGHT. A DOWNSTREAM UPPER LEVEL RIDGE
WILL AMPLIFY ACROSS THE SOUTHERN AND CENTRAL PLAINS FRIDAY...AND
THEN SLOWLY SHIFT EASTWARD INTO THE MID MS RIVER VALLEY BY SATURDAY
EVENING. THE LONGER WAVE LENGTH THROUGH WILL THEN RETROGRADE WESTWARD
ACROSS THE PACIFIC NORTHWEST AND THE UPPER RIDGE AXIS WILL EXPAND
WESTWARD ACROSS THE PLAINS INTO EARLY NEXT WEEK.
FRIDAY THROUGH WEDNESDAY...EXPECT HOT AND HUMID CONDITIONS.
AFTERNOON AND EVENING THUNDERSTORMS WILL DEVELOP ACROSS THE CENTRAL
AND NORTHERN HIGH PLAINS AND MOVE NORTHEAST ACROSS THE NORTHERN AND
CENTRAL PLAINS...WEST AND NORTH OF THE CWA.
AN UPPER LEVEL SHORT-WAVE TROUGH WILL LIFT NORTHEAST ACROSS THE
NORTHERN PLAINS INTO THE NORTHERN GREAT LAKES SATURDAY NIGHT THROUGH
MONDAY NIGHT. THIS MAY CAUSE A SLIGHT WEAKNESS TO THE UPPER RIDGE
AXIS AND MAY ALLOW ISOLATED THUNDERSTORMS TO DEVELOP SUNDAY
AFTERNOON AND SUNDAY NIGHT...THOUGH AREAS ALONG AND SOUTH OF I-70
MAY STAY DRY THROUGH THE PERIOD.
HIGHS WILL BE IN THE MID TO UPPER 90S. THERE MAY BE SLIGHT COOL DOWN
ON SUNDAY WHEN HIGHS MAY ONLY REACH THE LOWER TO MID 90S. HEAT
INDICES THROUGH THE PERIOD WILL GENERALLY REACH THE UPPER 90S TO
AROUND 102 DEGREES DURING THE AFTERNOON HOURS.
GARGAN
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z FRIDAY MORNING)
ISSUED AT 752 AM CDT THU JUN 20 2013
THUNDERSTORMS HAVE COMMENCED WEST OF KMHK IN THE LAST FEW
MINUTES...WHICH GOES IN LINE WITH WHAT MODELS HAVE BEEN HINTING
AT. AT THIS POINT IT LOOKS AS THOUGHT THE CONVECTIVE COMPLEX THIS
MORNING WILL OCCUR AND BRING THUNDERSTORMS NEAR THE TERMINALS
THROUGH THE MORNING HOURS. HAVE AMENDED THE AVIATION FORECAST FOR
THESE SHOWERS...WHICH SHOULD BE OUT OF THE AREA BY 18Z. LINGERING
BOUNDARIES COULD PLAY A ROLE IN AFTERNOON/EVENING CONVECTION...BUT
WILL CONTINUE TO MONITOR TRENDS THROUGH THE DAY.
JL
&&
.TOP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...WOLTERS
SHORT TERM...LEIGHTON
LONG TERM...GARGAN
AVIATION...LEIGHTON
AREA FORECAST DISCUSSION
NWS WICHITA KS
607 AM CDT THU JUN 20 2013
.SHORT TERM...(TODAY THROUGH FRIDAY)
ISSUED AT 332 AM CDT THU JUN 20 2013
MOISTURE INITIALIZATION CONTINUES TO BE VERY POOR AMONG MOST MODELS.
BOTH 00Z GFS/NAM GENERATED FICTITIOUS DEWPOINT GRADIENTS THAT
INFLUENCED CONVECTIVE DEVELOPMENT. THE 0000 UTC ECMWF WAS NOT TOO
BAD...AND THE HRRR WAS BETTER AND HAS BEEN PERSISTENT IN
DEVELOPING PRECIPITATION OVER FLINT HILLS TOWARDS DAYBREAK. SOME
RELATIVELY FLAT ALTOCUMULUS WAS EVIDENT VISUALLY AROUND SUNSET...
AND THIS MAY BE ONLY CHANCE FOR PRECIPITATION THIS MORNING. 0000
UTC UPPER AIR ANALYSIS SUGGEST WEAK TROUGH MOVING THROUGH AT THIS
TIME...SO DEVELOPMENT IMMEDIATELY UPSTREAM IS UNLIKELY. WITH
INCREASING PRESSURE GRADIENT AND GOOD MIXING...GUSTY WINDS ARE
LIKELY BY MIDDAY AND COULD SEE SPEEDS FLIRTING WITH ADVISORY
CRITERIA IN THE FAVORED AREAS OF CENTRAL KS. GIVEN IT APPEARS
MARGINAL AT THE MOMENT...WILL HOLD OFF ON HEADLINES. CHANCES FOR
PRECIPITATION LOOK SLIM BY AFTERNOON/EVENING WITH INCREASING
TEMPERATURES ALOFT.
WHILE POSSIBLE THAT PRECIPITATION COULD DEVELOP UPSTREAM THU
NIGHT/EARLY FRI...ODDS LOOK TOO LOW TO MENTION AT THIS TIME.
TEMPERATURES ON FRI WILL CONTINUE TO CLIMB WITH WARM/WINDY
CONDITIONS DURING THE DAY. -HOWERTON
.LONG TERM...(SATURDAY THROUGH WEDNESDAY)
ISSUED AT 332 AM CDT THU JUN 20 2013
SAT-SUN:
SHORTWAVE MAY EDGE FRONT CLOSE ENOUGH TO SPREAD PRECIPITATION
INTO FAR NORTHWESTERN SECTIONS SUN NIGHT...BUT NOT VERY
OPTIMISTIC. PROXIMITY OF FRONT WILL LIKELY ONLY HAD MORE HEAT TO
THE WARMUP.
FOR MON-WED:
WILL CONTINUE THE DRY AND WARM FORECAST THROUGH AT LEAST
TUE...HOWEVER BOTH GFS/ECMWF HINTING AT A BREAKDOWN OF THE UPPER
RIDGE BY WED. NOT PARTICULARLY OPTIMISTIC ABOUT THIS BUT DID GO
ALONG WITH A DEGREE OR TWO COOLER IN THE NORTH PER CONSENSUS.
ISOLATED STORMS CANNOT BE RULED OUT WITH PEAK HEATING...BUT ODDS
ARE TOO LOW TO MENTION. -HOWERTON
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z FRIDAY MORNING)
ISSUED AT 603 AM CDT THU JUN 20 2013
LOW CLOUDS WILL CONTINUE TO MOVE EASTWARD ACROSS CENTRAL KANSAS
THIS MORNING BUT SHOULD SCATTER OUT AROUND MID-MORNING. THERE IS A
SLIGHT CHANCE FOR A FEW THUNDERSTORMS TO DEVELOP THIS MORNING BUT
CONDITIONS ARE LOOKING DRY FOR THE AFTERNOON AND TONIGHT PERIOD.
SOUTH WINDS WILL INCREASE TODAY AND BECOME QUITE GUSTY.
JAKUB
&&
.PRELIMINARY POINT TEMPS/POPS...
WICHITA-KICT 92 73 93 73 / 20 10 10 10
HUTCHINSON 94 73 95 73 / 10 10 10 10
NEWTON 94 72 94 72 / 20 10 10 10
ELDORADO 91 73 92 73 / 20 10 10 10
WINFIELD-KWLD 91 73 93 73 / 20 10 10 10
RUSSELL 98 73 98 73 / 10 10 10 10
GREAT BEND 96 72 97 72 / 10 10 10 10
SALINA 95 74 96 74 / 10 10 10 10
MCPHERSON 95 73 96 73 / 10 10 10 10
COFFEYVILLE 90 73 92 72 / 20 10 10 10
CHANUTE 88 72 91 71 / 30 10 10 10
IOLA 88 72 91 71 / 30 10 10 10
PARSONS-KPPF 89 73 91 72 / 30 10 10 10
&&
.ICT WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS WICHITA KS
339 AM CDT THU JUN 20 2013
.SHORT TERM...(TODAY THROUGH FRIDAY)
ISSUED AT 332 AM CDT THU JUN 20 2013
MOISTURE INITIALIZATION CONTINUES TO BE VERY POOR AMONG MOST MODELS.
BOTH 00Z GFS/NAM GENERATED FICTIOUS DEWPOINT GRADIENTS THAT
INFLUENCED CONVECTIVE DEVELOPMENT. THE 0000 UTC ECMWF WAS NOT TOO
BAD...AND THE HRRR WAS BETTER AND HAS BEEN PERSISTENT IN
DEVELOPING PRECIPITATION OVER FLINT HILLS TOWARDS DAYBREAK. SOME
RELATIVELY FLAT ALTOCUMULUS WAS EVIDENT VISUALLY AROUND SUNSET...
AND THIS MAY BE ONLY CHANCE FOR PRECIPITATION THIS MORNING. 0000
UTC UPPER AIR ANALYSIS SUGGEST WEAK TROUGH MOVING THROUGH AT THIS
TIME...SO DEVELOPMENT IMMEDIATELY UPSTREAM IS UNLIKELY. WITH
INCREASING PRESSURE GRADIENT AND GOOD MIXING...GUSTY WINDS ARE
LIKELY BY MIDDAY AND COULD SEE SPEEDS FLIRTING WITH ADVISORY
CRITERIA IN THE FAVORED AREAS OF CENTRAL KS. GIVEN IT APPEARS
MARGINAL AT THE MOMENT...WILL HOLD OFF ON HEADLINES. CHANCES FOR
PRECIPITATION LOOK SLIM BY AFTERNOON/EVENING WITH INCREASING
TEMPERATURES ALOFT.
WHILE POSSIBLE THAT PRECIPITATION COULD DEVELOP UPSTREAM THU
NIGHT/EARLY FRI...ODDS LOOK TOO LOW TO MENTION AT THIS TIME.
TEMPERATURES ON FRI WILL CONTINUE TO CLIMB WITH WARM/WINDY
CONDITIONS DURING THE DAY. -HOWERTON
.LONG TERM...(SATURDAY THROUGH WEDNESDAY)
ISSUED AT 332 AM CDT THU JUN 20 2013
SAT-SUN:
SHORTWAVE MAY EDGE FRONT CLOSE ENOUGH TO SPREAD PRECIPITATION
INTO FAR NORTHWESTERN SECTIONS SUN NIGHT...BUT NOT VERY
OPTIMISTIC. PROXIMITY OF FRONT WILL LIKELY ONLY HAD MORE HEAT TO
THE WARMUP.
FOR MON-WED:
WILL CONTINUE THE DRY AND WARM FORECAST THROUGH AT LEAST
TUE...HOWEVER BOTH GFS/ECMWF HINTING AT A BREAKDOWN OF THE UPPER
RIDGE BY WED. NOT PARTICULARLY OPTIMISTIC ABOUT THIS BUT DID GO
ALONG WITH A DEGREE OR TWO COOLER IN THE NORTH PER CONSENSUS.
ISOLATED STORMS CANNOT BE RULED OUT WITH PEAK HEATING...BUT ODDS
ARE TOO LOW TO MENTION. -HOWERTON
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z THURSDAY NIGHT)
ISSUED AT 1139 PM CDT WED JUN 19 2013
BREEZY SOUTHEAST WINDS WILL INCREASE SHORTLY AFTER SUNRISE INTO
THE 20-25 KNOT RANGE WITH GUSTS INTO THE LOW 30S. SPEEDS MAY APPROACH
ADVISORY CRITERIA AT TIMES AFTER 20-21Z. WIDELY SCATTERED
THUNDERSTORMS MAY ALSO DEVELOP AFTER 09-10Z ALONG AND WEST OF
I-135 AND DRIFT EASTWARD THROUGH THE MORNING HOURS. MAINTAINED
VCTS AT TAF SITES THROUGH THE EARLY MORNING HOURS.
MWM
&&
.PRELIMINARY POINT TEMPS/POPS...
WICHITA-KICT 92 73 93 73 / 20 10 10 10
HUTCHINSON 94 73 95 73 / 10 10 10 10
NEWTON 94 72 94 72 / 20 10 10 10
ELDORADO 91 73 92 73 / 20 10 10 10
WINFIELD-KWLD 91 73 93 73 / 20 10 10 10
RUSSELL 98 73 98 73 / 10 10 10 10
GREAT BEND 96 72 97 72 / 10 10 10 10
SALINA 95 74 96 74 / 10 10 10 10
MCPHERSON 95 73 96 73 / 10 10 10 10
COFFEYVILLE 90 73 92 72 / 20 10 10 10
CHANUTE 88 72 91 71 / 30 10 10 10
IOLA 88 72 91 71 / 30 10 10 10
PARSONS-KPPF 89 73 91 72 / 30 10 10 10
&&
.ICT WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS TOPEKA KS
1210 AM CDT THU JUN 20 2013
...UPDATE TO AVIATION...
.SHORT TERM...(THIS EVENING THROUGH THURSDAY)
ISSUED AT 301 PM CDT WED JUN 19 2013
19Z WATER VAPOR IMAGERY SHOWS A CLOSED UPPER LEVEL LOW OVER THE
PACIFIC NORTHWEST WITH A SHORTWAVE ROTATING THROUGH THE TROUGH OVER
THE GREAT SALT LAKE. DOWNSTREAM THERE WAS A BROAD UPPER LEVEL RIDGE
OVER THE PLAINS WITH A WEAK DISTURBANCE NEAR THE MIDDLE MO RIVER
VALLEY MOVING EAST. AT THE SURFACE...A TROUGH OF LOW PRESSURE WAS
GRADUALLY DEEPENING ALONG THE LEE OF THE CENTRAL ROCKIES. THIS HAS
ALLOWED FOR SOUTHERLY WINDS TO INCREASE. ANY REMNANT OUTFLOW
BOUNDARIES FROM EARLY THIS MORNING HAVE BECOME ILL-DEFINED.
FOR LATE THIS AFTERNOON AND THIS EVENING...LAPS DATA AND RAP
ANALYSIS SHOWS A CONDITIONALLY UNSTABLE AIRMASS OVER THE FORECAST
AREA WITH CAPE VALUES AROUND 2000 J/KG...AND VERY LIMITED INHIBITION
LEFT. REALLY THE ONLY THING NEEDED FOR CONVECTION IS SOME SORT OF
LIFT TO GET PARCELS MOVING UP TO BECOME POSITIVELY BUOYANT. LOW LEVEL
CONVERGENCE APPEARS TO BE RELATIVELY WEAK WITH RAP PROGS NOT SHOWING
MUCH INCREASE IN LOW LEVEL CONVERGENCE THROUGH SUNSET. WITH NO REAL
LARGE SCALE FORCING TO SPEAK OF...THINK CONVECTION IS LIKELY TO BE
ISOLATED IF IT DOES DEVELOP. THERE IS SOME SIGNS OF VERTICAL
DEVELOPMENT IN THE CU FIELD ACROSS SOUTHEAST NEB. IF A STORM IS ABLE
TO DEVELOP AN OUTFLOW...THE GUST FRONT COULD BE ENOUGH LIFT FOR
FURTHER DEVELOPMENT. OTHERWISE THINK THE BETTER CHANCES FOR PRECIP
WILL BE LATE TONIGHT AND THROUGH THE MORNING THURSDAY. MOST GUIDANCE
SHOWS DECENT MID LEVEL THETA-E ADVECTION WITH THE LOW LEVEL JET
INCREASING OVER CENTRAL KS. FORECAST SOUNDINGS SHOW INCREASING
MOISTURE ALONG THIS GRADIENT AS MID LEVEL LAPSE RATES STEEPEN TO
AROUND 7 C/KM. THEREFORE THERE COULD BE SOME ELEVATED STORMS DEVELOP
OVERNIGHT AND MOVE ACROSS EASTERN KS THROUGH THE MORNING THURSDAY.
LOW CONFIDENCE IN LOCATION OF THE ELEVATED DEVELOPMENT AND WHERE IT
MIGHT TRACK PRECLUDE INCREASING POPS FROM THE PREV FORECAST. SO HAVE
CONTINUED WITH 40 TO 50 PERCENT CHANCES INTO THURSDAY MORNING. THINK
IF ELEVATED STORMS FORM...THAT THE RESULTING MCS SHOULD BE MOVING
OFF TO THE SOUTHEAST OR DIMINISHING WITH THE WEAKENING OF THE LOW
LEVEL JET BY THE AFTERNOON AND THE POP FORECAST REFLECTS A DOWNWARD
TREND IN CHANCES THROUGH THE AFTERNOON.
SOUTHERLY WINDS AND SOME MODEST MIXING OF THE BOUNDARY LAYER SHOULD
KEEP LOWS TONIGHT IN THE UPPER 60S TO AROUND 70. HIGHS THURSDAY MAY
BE A LITTLE MORE TRICKY AS THE MODELS SHOW WEAK MIXING OF THE
BOUNDARY LAYER DUE TO COLD POOL PUT DOWN BY THE NOCTURNAL
CONVECTION. EVEN IF THERE ARE STORMS...DO NOT THINK THEY WILL
PERSIST FOR THE WHOLE DAY AND WE SHOULD STILL SEE SOME GOOD
INSOLATION IN THE AFTERNOON WITH SOUTH WINDS INCREASING. THEREFORE
HAVE HIGHS FOR THURSDAY IN THE MID 80S ACROSS EAST CENTRAL KS WHERE
CLOUDS AND PRECIP COULD POTENTIALLY HANG ON LONGER IN THE
MORNING...TO AROUND 90 IN NORTH CENTRAL KS WHERE SUNSHINE SHOULD
BREAK OUT EARLIER IN THE DAY.
WOLTERS
.LONG TERM...(THURSDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 301 PM CDT WED JUN 19 2013
THURSDAY NIGHT AND FRIDAY...SOME CONCERN AS TO CONVECTION
REDEVELOPING LATE THURSDAY NIGHT/EARLY FRIDAY MORNING. THURSDAY
AFTERNOON THUNDERSTORM COMPLEX EXPECTED TO DEVELOP ALONG SFC WARM
FRONT DRAPED OVER CENTRAL NEBRASKA AND WESTERN IOWA. NAM FORECASTED
CONVECTIVELY GENERATED COLD POOL MAY PUSH FRONTAL BOUNDARY SOUTH
POTENTIALLY OVER SOUTHERN NEBRASKA/NORTHEAST KANSAS BY FRIDAY
MORNING. 305K-320K ISENTROPIC LIFT...55KT LLJ AND SOME MID-LEVEL
FRONTOGENETICAL FORCING COULD BE ENOUGH TO PROMOTE REDEVELOPMENT OF
CONVECTION MAINLY OVER THE FAR NORTHEASTERN SECTIONS OF THE STATE.
UPPER LEVEL FORCING IS LACKING HOWEVER...LEAVING REDUCED
CONFIDENCE. LEFT FRIDAY AFTERNOON DRY ATTM. HOWEVER...IF
CONVECTION DEVELOPS DURING THE EARLY MORNING HOURS...OUTFLOW
BOUNDARIES MAY STILL BE PRESENT DURING THE AFTERNOON ACROSS THE
CWA. WITH A H5 SHRTWV PROGGED TO ENTER THE STATE FRIDAY
AFTERNOON...THIS MAY BE ENOUGH TO REFIRE CONVECTION DURING THE
AFTERNOON HOURS. TEMPERATURES WILL BE ON THE INCREASE OVER THE
COMING WEEK AS LARGE UPPER LEVEL RIDGE BEGINS TO BUILD INTO THE
CENTRAL U.S. HEAT INDICES COULD REACH OVER 100 FRIDAY AFTERNOON.
FRIDAY NIGHT THROUGH THE REST OF THE WEEK...RIDGE CONTINUES TO
BROADEN ACROSS THE PLAINS ON SATURDAY WITH THE RIDGE AXIS EXTENDING
FROM EASTERN COLORADO/WESTERN KANSAS THROUGH NORTHEAST KANSAS AND
INTO THE UPPER MIDWEST. SLIGHT CHANCES FOR THUNDERSTORMS WILL BE
POSSIBLE ALONG THE NORTHERN SIDE OF THE RIDGE ON SUNDAY. CHANCES
INCREASE FOR LOCATIONS NORTH OF I70 SUNDAY NIGHT AS AN H5 SHRTWV
TRAVELS NORTHEAST ALONG THE NORTHERN PERIPHERY OF THE RIDGE. COLD
FRONT TRIES TO PUSH SOUTHEAST INTO KANSAS ON TUESDAY...BUT UPPER
LEVEL SUPPORT FOR THE FRONT MOVES INTO CANADA BY MONDAY AFTERNOON.
OTHERWISE...CENTRAL PLAINS RIDGE BROADENS AND COVERS MUCH OF THE
CONUS BY TUESDAY. RIDGE BEGINS TO AMPLIFY OVER THE WESTERN U.S. BY
WEDNESDAY AFTERNOON SETTING UP THE SUMMER TIME PATTERN OF NORTHWEST
FLOW OVER THE CENTRAL PLAINS. HIGHS WILL BE IN THE LOW TO MID
90`S...AND LOWS WILL BE IN THE 60`S AND 70`S.
BYRNE
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z THURSDAY NIGHT)
ISSUED AT 1142 PM CDT WED JUN 19 2013
VFR CONDITIONS STILL EXPECTED THROUGH THE TAF PERIOD. MAIN
UNCERTAINTY REMAINS IN THUNDERSTORM POTENTIAL AND TIMING.
MONITORING POTENTIAL FOR STORMS OVER TAF SITES AS EARLY AS 09Z...
BUT FEEL MOST LIKELY TIME IS AFTER SUNRISE. IF STORMS INDEED
DEVELOP THURSDAY MORNING...WEAK OUTFLOW BOUNDARIES MAY SERVE AS A
FOCUS FOR ISOLATED BUT STRONG AFTERNOON TS...SO KEPT VCTS FOR MUCH
OF THE DAY GIVEN THE PERSISTENT POTENTIAL FOR SCATTERED TS. COULD
ALSO SEE SOUTH WINDS GUST TO 25 KTS OR BETTER DURING DAYLIGHT
HOURS.
&&
.TOP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...WOLTERS
LONG TERM...BYRNE
AVIATION...BARJENBRUCH
AREA FORECAST DISCUSSION
NWS WICHITA KS
1143 PM CDT WED JUN 19 2013
.UPDATE...
ISSUED AT 655 PM CDT WED JUN 19 2013
DELAYED POPS UNTIL AFTER 07-08Z WHEN BETTER H9-H8 MOISTURE
TRANSPORT/CONVERGENCE ALONG THE NOSE OF THE LLJ SHOULD ALLOW FOR
SCATTERED THUNDERSTORM DEVELOPMENT ACROSS CENTRAL KANSAS.
&&
.SHORT TERM...(THIS EVENING THROUGH THURSDAY)
ISSUED AT 329 PM CDT WED JUN 19 2013
FORECAST HIGHLIGHTS FOCUS AROUND THUNDERSTORM CHANCES TONIGHT
THROUGH THURSDAY MORNING...WITH HOT AND MOSTLY DRY SUMMER WEATHER
LIKELY LATE THIS WEEK THROUGH AT LEAST EARLY TO MID NEXT WEEK.
DIFFICULT THUNDERSTORM FORECAST TONIGHT-THURSDAY MORNING. CURRENTLY
A WEAK 700-500MB RIPPLE IS ADVANCING EAST ACROSS EASTERN KS. GIVEN
THIS FEATURE ALONG WITH THE RELATIVELY UNCAPPED AIRMASS IN
PLACE...CANNOT RULE OUT A FEW ISOLATED HIT-AND-MISS THUNDERSTORMS
LATE THIS AFTERNOON THROUGH ABOUT SUNSET. NOT ANTICIPATING
WIDESPREAD COVERAGE THOUGH. FOCUS THEN TURNS TO LATER TONIGHT WHEN
EASTERN FRINGE OF ADVANCING ELEVATED MIXED LAYER APPROACHES FROM THE
WEST...DRAMATICALLY INCREASING 800-600MB WARM/MOIST ADVECTION FROM
WEST TO EAST...RESULTING IN A CHANCE OF THUNDERSTORMS AFTER 2-3AM
WEST OF THE FLINT HILLS. THE HIGHEST CHANCES MAY BE OVER
CENTRAL/EAST-CENTRAL KS WHERE NOSE OF MOISTURE TRANSPORT IS
POINTING. NAM AND GFS ELEVATED INSTABILITY PROGS INDICATE ~2500 J/KG
INSTABILITY FROM PARCELS ROOTED AROUND 800MB...ALONG WITH AROUND 30
KTS OF EFFECTIVE SHEAR...INDICATING STRONG TO SEVERE HAILERS ARE
POSSIBLE WITH ANY STORMS THAT CAN FORM. HOWEVER...UNSURE ON HOW
WIDESPREAD ACTIVITY WILL BE GIVEN THE CONVECTION-SUPPRESSING AFFECTS
OF MID/UPPER RIDGING DEVELOPING ACROSS THE REGION OVERNIGHT...WHICH
MAY BE A REASON WHY THE LATEST HRRR AND KF NAM STRUGGLE IN
DEVELOPING OVERNIGHT CONVECTION. AGAIN...HIGHEST POTENTIAL MAY
REMAIN OVER CENTRAL/EAST-CENTRAL KS AND POINTS NORTH.
NEVERTHELESS...HELD ONTO MODEST CHANCE POPS GIVEN STRENGTH OF
ISENTROPIC ASCENT/MOISTURE TRANSPORT. ANTICIPATING ACTIVITY TO
FESTER MUCH OF THU MORNING EAST OF I-135...AND POSSIBLY INTO THE
AFTERNOON EAST OF THE FLINT HILLS.
ADK
.LONG TERM...(FRIDAY THROUGH WEDNESDAY)
ISSUED AT 329 PM CDT WED JUN 19 2013
OTHERWISE...BUILDING MID/UPPER RIDGE WILL LIKELY SUPPRESS WIDESPREAD
THUNDERSTORM CHANCES FROM FRIDAY THROUGH AT LEAST EARLY TO MID NEXT
WEEK...AND ALLOW ABOVE NORMAL SUMMER HEAT TO BUILD ACROSS THE
REGION. CANNOT COMPLETELY RULE OUT A FEW ISOLATED HIT-AND-MISS
AFTERNOON-EVENING THUNDERSTORMS FRI-SAT...AS ECMWF HINTS AT SUBTLE
WEAKNESSES PROGRESSING OVER THE AREA...BUT THINKING THIS THREAT WILL
BE QUITE ISOLATED. OTHERWISE...WITH GFS ENSEMBLES AND OPERATIONAL
ECMWF BUILDING RIDGE INTO EARLY/MID NEXT WEEK...CONFIDENCE IS HIGH
THAT ABOVE NORMAL SUMMER HEAT IN THE 90S TO LOW 100S WILL PREVAIL
REGIONWIDE...WARMEST GENERALLY OVER THE WESTERN HALF OF KS...WITH
OVERNIGHT LOWS IN THE 70S ALL AREAS.
ADK
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z THURSDAY NIGHT)
ISSUED AT 1139 PM CDT WED JUN 19 2013
BREEZY SOUTHEAST WINDS WILL INCREASE SHORTLY AFTER SUNRISE INTO
THE 20-25 KNOT RANGE WITH GUSTS INTO THE LOW 30S. SPEEDS MAY APPROACH
ADVISORY CRITERIA AT TIMES AFTER 20-21Z. WIDELY SCATTERED
THUNDERSTORMS MAY ALSO DEVELOP AFTER 09-10Z ALONG AND WEST OF
I-135 AND DRIFT EASTWARD THROUGH THE MORNING HOURS. MAINTAINED
VCTS AT TAF SITES THROUGH THE EARLY MORNING HOURS.
MWM
&&
.PRELIMINARY POINT TEMPS/POPS...
WICHITA-KICT 70 90 73 95 / 40 40 10 10
HUTCHINSON 69 93 73 96 / 40 30 10 10
NEWTON 68 88 73 94 / 40 50 10 10
ELDORADO 69 87 72 92 / 40 40 10 10
WINFIELD-KWLD 70 89 73 93 / 30 40 10 10
RUSSELL 68 97 73 98 / 40 10 10 10
GREAT BEND 68 97 72 97 / 30 10 10 10
SALINA 70 91 74 96 / 50 50 10 10
MCPHERSON 69 91 73 96 / 40 50 10 10
COFFEYVILLE 69 85 73 91 / 30 40 10 10
CHANUTE 68 84 72 90 / 30 40 10 10
IOLA 68 84 71 90 / 30 40 10 10
PARSONS-KPPF 69 84 73 90 / 30 40 10 10
&&
.ICT WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS JACKSON KY
900 PM EDT FRI JUN 21 2013
.UPDATE...
ISSUED AT 900 PM EDT FRI JUN 21 2013
THUNDERSTORMS HAVE DIED DOWN IN OUR FORECAST AREA...BUT ISOLATED
STORMS CONTINUE TO FIRE AROUND US. INHERITED FORECAST DROPPED ALL
MENTION OF POPS AFTER 00Z EXCEPT DOWN SOUTH ALONG THE TN AND VA
BORDERS AND KEPT WITH THIS THINKING. WILL NEED TO MONITOR THE STORMS
FIRING OVER THE BLUEGRASS THOUGH TO MAKE SURE ADDITIONAL ACTIVITY
DOESN/T FIRE ON OUTFLOWS INTO OUR BLUEGRASS COUNTIES. OTHERWISE...
SHOULD BE A QUIET NIGHT WITH REPEAT VALLEY FOG DEVELOPMENT. FORECAST
LOWS IN THE LOW TO MID 60S LOOK GOOD.
&&
.SHORT TERM...(THIS EVENING THROUGH SATURDAY NIGHT)
ISSUED AT 314 PM EDT FRI JUN 21 2013
BEEN WATCHING THE MCS ENTERING NORTHERN ILL TO SEE HOW FAR SOUTH IT
WILL KEEP GOING AND WHERE THE OUTFLOW BOUNDARIES END UP. CURRENT
THINKING IS THAT IF IT DOES NOT FALL APART BEFORE IT REACHES THE
AREA...IT SHOULD STAY WEST OF THE AREA. THE HRRR IS SHOWING ISOLATED
TO SCATTERED SHOWERS AND THUNDERSTORMS DEVELOPING DURING THE
AFTERNOON AND EVENING HOURS. THE INSTABILITY IS THERE TO SUPPORT
THUNDERSTORM DEVELOPMENT. ONE CONCERN IS THE DRY AIR IN THE MID
LAYERS WHICH COULD HELP TO PRODUCE SOME STRONG OUTFLOW WINDS. THE
OTHER CONCERN IS THAT THE WINDS ALOFT ARE SO LIGHT...THE STORMS WILL
BE MOVING VERY SLOWLY. THIS MAY ALLOW A LOT OF PRECIPITATION TO FALL
OVER A SMALL AREA AND COULD RESULT IN DITCHES AND LOW WATER
CROSSINGS TO RUN FULL. THERE HAS ALREADY BEEN ONE STRONG STORM
DEVELOP OVER LESLIE COUNTY THIS AFTERNOON. NO REPORTS OF ANY DAMAGE
OR FLOODING WERE RECEIVED. A REPEAT OF THIS DIURNALLY BASED PULSE
THUNDERSTORM ACTIVITY IS ANTICIPATED ON SATURDAY.
.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 314 PM EDT FRI JUN 21 2013
FAIRLY BUSY PATTERN FOR THE OFFICIAL START OF SUMMER. OVERALL
MODELS ARE IN GOOD AGREEMENT THROUGH THE EXTENDED. IN FAIRLY HIGH
AMPLITUDE FLOW...CORE WESTERLIES REMAINS NORTH OF OUR AREA UNTIL THE
END OF THE FORECAST WINDOW. EASTERN CONUS RIDGING ALOFT RETREATS
WESTWARD WITH TIME THROUGH THE PERIOD. EMBEDDED WITHIN THIS RIDGE
EARLY ON IS AN AREA OF TROUGH-I-NE SS OR A CENTER OF RELATIVE LOWER
HEIGHTS. THIS LOCALIZED AREA OF LOWER HEIGHTS WILL OPEN UP AND DRIFT
NORTHEAST THROUGH THE LATTER PART OF THE WEEKEND AND EARLY NEXT
WEEK...SPREADING ITS LIMITED INFLUENCE THROUGH THE SOUTHERN
APPALACHIANS. FOR SUCH A WEAK FEATURE...CONSISTENT WITH THIS TIME OF
YEAR...THE MODELS DO RATHER WELL IN DEPICTING SIMILAR EVOLUTIONS...
THOUGH THE ECMWF MAINTAINS THE DISTINCT UPPER LOW LONGER THAN THE
GFS. THIS RIDGING ACROSS THE REGION IS SUPPRESSED SOUTHWARD AS THIS
AREA OF LOWER HEIGHTS GRADUALLY LIFTS NORTHWARD ACROSS EASTERN
KENTUCKY SUNDAY. THEREAFTER THE RIDGE SHIFTS WESTWARD AND THE
PATTERN AMPLIFIES...RESULTING IN ENERGY ALONG THE NORTHERN TIER
SETTLING SOUTHWARD ALONG THE EASTERN SIDE OF THE RIDGE...EFFECTIVELY
CARVING OUT A TROUGH OVER THE EASTERN CONUS TO FINISH OUT THE WEEK.
SENSIBLE WEATHER WILL BE DOMINATED BY THE DIURNAL CYCLE THROUGH THE
BULK OF THE EXTENDED AS SFC HIGH PRESSURE OVER THE AREA WILL BE TOO
WEAK TO SUPPRESS ALL CONVECTION ONCE DAYTIME HEATING KICKS IN. THERE
IS REALLY NO FEATURE TO KEY IN ON FOR MORE ORGANIZED...WIDESPREAD
ACTIVITY THROUGH THE START OF THE UPCOMING WORK WEEK. THAT CHANGES
TOWARDS WEEKS END AS A STORM SYSTEM DROPPING SOUTHWARD OUT OF CANADA
HELPS TO GENERATE A BETTER CHANCE FOR RAIN ACROSS OUR AREA...THOUGH
TIMING AND SPECIFICS REMAIN IN DOUBT. WARM AND SEASONABLE WEATHER IS
THUS ON TAP FOR THE REST OF THE WEEKEND AND THROUGH THE START OF THE
NEW WORK WEEK. DURING THE FIRST FEW DAYS OF THE EXTENDED...OUR BEST
OPPORTUNITY FOR SOME GARDEN VARIETY...HIT AND MISS THUNDERSTORMS
APPEARS TO BE SUNDAY AS HEIGHTS DROP SLIGHTLY DUE TO THE PASSING
FEATURE...DISTURBANCE FROM THE SOUTH. ADDITIONAL CLOUD COVER...AND A
BETTER POTENTIAL OF CONVECTION AFTER MID WEEK ON SHOULD HELP TEMPER
THE WARMTH A BIT.
FOR TEMPS GENERALLY STAYED CLOSE TO A BLEND OF MODEL GUIDANCE WHILE
MAINTAINING EFFECTS OF RELATIVE ELEVATION AL DIFFERENCES...WHERE
APPLICABLE.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z SATURDAY EVENING)
ISSUED AT 746 PM EDT FRI JUN 21 2013
SURFACE HIGH PRESSURE WILL PROVIDE FOR MAINLY VFR CONDITIONS AND
LIGHT WINDS ACROSS THE AREA THROUGH THE PERIOD. EXPECT ISOLATED
THUNDERSTORMS TO DIE WITH THE SETTING SUN THIS EVENING AND THEN
REFIRE ABOUT THE SAME TIME TOMORROW...WITH SIMILAR COVERAGE. WE
CURRENTLY ANTICIPATE THE THUNDERSTORM CLUSTER DIVING DOWN THROUGH
INDIANA TO STAY TO THE WEST OF OUR REGION. PATCHY VALLEY FOG WILL
DEVELOP OVERNIGHT...AND WILL FORECAST A COUPLE HOURS OF MVFR AT LOZ
AND SME DUE TO A CONTINUED STEADY INCREASE IN SURFACE DEWPOINTS.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...ABE
SHORT TERM...JJ
LONG TERM...GREIF/RAY
AVIATION...ABE
AREA FORECAST DISCUSSION
NWS JACKSON KY
746 PM EDT FRI JUN 21 2013
.SHORT TERM...(THIS EVENING THROUGH SATURDAY NIGHT)
ISSUED AT 314 PM EDT FRI JUN 21 2013
BEEN WATCHING THE MCS ENTERING NORTHERN ILL TO SEE HOW FAR SOUTH IT
WILL KEEP GOING AND WHERE THE OUTFLOW BOUNDARIES END UP. CURRENT
THINKING IS THAT IF IT DOES NOT FALL APART BEFORE IT REACHES THE
AREA...IT SHOULD STAY WEST OF THE AREA. THE HRRR IS SHOWING ISOLATED
TO SCATTERED SHOWERS AND THUNDERSTORMS DEVELOPING DURING THE
AFTERNOON AND EVENING HOURS. THE INSTABILITY IS THERE TO SUPPORT
THUNDERSTORM DEVELOPMENT. ONE CONCERN IS THE DRY AIR IN THE MID
LAYERS WHICH COULD HELP TO PRODUCE SOME STRONG OUTFLOW WINDS. THE
OTHER CONCERN IS THAT THE WINDS ALOFT ARE SO LIGHT...THE STORMS WILL
BE MOVING VERY SLOWLY. THIS MAY ALLOW A LOT OF PRECIPITATION TO FALL
OVER A SMALL AREA AND COULD RESULT IN DITCHES AND LOW WATER
CROSSINGS TO RUN FULL. THERE HAS ALREADY BEEN ONE STRONG STORM
DEVELOP OVER LESLIE COUNTY THIS AFTERNOON. NO REPORTS OF ANY DAMAGE
OR FLOODING WERE RECEIVED. A REPEAT OF THIS DIURNALLY BASED PULSE
THUNDERSTORM ACTIVITY IS ANTICIPATED ON SATURDAY.
.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 314 PM EDT FRI JUN 21 2013
FAIRLY BUSY PATTERN FOR THE OFFICIAL START OF SUMMER. OVERALL
MODELS ARE IN GOOD AGREEMENT THROUGH THE EXTENDED. IN FAIRLY HIGH
AMPLITUDE FLOW...CORE WESTERLIES REMAINS NORTH OF OUR AREA UNTIL THE
END OF THE FORECAST WINDOW. EASTERN CONUS RIDGING ALOFT RETREATS
WESTWARD WITH TIME THROUGH THE PERIOD. EMBEDDED WITHIN THIS RIDGE
EARLY ON IS AN AREA OF TROUGH-I-NE SS OR A CENTER OF RELATIVE LOWER
HEIGHTS. THIS LOCALIZED AREA OF LOWER HEIGHTS WILL OPEN UP AND DRIFT
NORTHEAST THROUGH THE LATTER PART OF THE WEEKEND AND EARLY NEXT
WEEK...SPREADING ITS LIMITED INFLUENCE THROUGH THE SOUTHERN
APPALACHIANS. FOR SUCH A WEAK FEATURE...CONSISTENT WITH THIS TIME OF
YEAR...THE MODELS DO RATHER WELL IN DEPICTING SIMILAR EVOLUTIONS...
THOUGH THE ECMWF MAINTAINS THE DISTINCT UPPER LOW LONGER THAN THE
GFS. THIS RIDGING ACROSS THE REGION IS SUPPRESSED SOUTHWARD AS THIS
AREA OF LOWER HEIGHTS GRADUALLY LIFTS NORTHWARD ACROSS EASTERN
KENTUCKY SUNDAY. THEREAFTER THE RIDGE SHIFTS WESTWARD AND THE
PATTERN AMPLIFIES...RESULTING IN ENERGY ALONG THE NORTHERN TIER
SETTLING SOUTHWARD ALONG THE EASTERN SIDE OF THE RIDGE...EFFECTIVELY
CARVING OUT A TROUGH OVER THE EASTERN CONUS TO FINISH OUT THE WEEK.
SENSIBLE WEATHER WILL BE DOMINATED BY THE DIURNAL CYCLE THROUGH THE
BULK OF THE EXTENDED AS SFC HIGH PRESSURE OVER THE AREA WILL BE TOO
WEAK TO SUPPRESS ALL CONVECTION ONCE DAYTIME HEATING KICKS IN. THERE
IS REALLY NO FEATURE TO KEY IN ON FOR MORE ORGANIZED...WIDESPREAD
ACTIVITY THROUGH THE START OF THE UPCOMING WORK WEEK. THAT CHANGES
TOWARDS WEEKS END AS A STORM SYSTEM DROPPING SOUTHWARD OUT OF CANADA
HELPS TO GENERATE A BETTER CHANCE FOR RAIN ACROSS OUR AREA...THOUGH
TIMING AND SPECIFICS REMAIN IN DOUBT. WARM AND SEASONABLE WEATHER IS
THUS ON TAP FOR THE REST OF THE WEEKEND AND THROUGH THE START OF THE
NEW WORK WEEK. DURING THE FIRST FEW DAYS OF THE EXTENDED...OUR BEST
OPPORTUNITY FOR SOME GARDEN VARIETY...HIT AND MISS THUNDERSTORMS
APPEARS TO BE SUNDAY AS HEIGHTS DROP SLIGHTLY DUE TO THE PASSING
FEATURE...DISTURBANCE FROM THE SOUTH. ADDITIONAL CLOUD COVER...AND A
BETTER POTENTIAL OF CONVECTION AFTER MID WEEK ON SHOULD HELP TEMPER
THE WARMTH A BIT.
FOR TEMPS GENERALLY STAYED CLOSE TO A BLEND OF MODEL GUIDANCE WHILE
MAINTAINING EFFECTS OF RELATIVE ELEVATION AL DIFFERENCES...WHERE
APPLICABLE.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z SATURDAY EVENING)
ISSUED AT 746 PM EDT FRI JUN 21 2013
SURFACE HIGH PRESSURE WILL PROVIDE FOR MAINLY VFR CONDITIONS AND
LIGHT WINDS ACROSS THE AREA THROUGH THE PERIOD. EXPECT ISOLATED
THUNDERSTORMS TO DIE WITH THE SETTING SUN THIS EVENING AND THEN
REFIRE ABOUT THE SAME TIME TOMORROW...WITH SIMILAR COVERAGE. WE
CURRENTLY ANTICIPATE THE THUNDERSTORM CLUSTER DIVING DOWN THROUGH
INDIANA TO STAY TO THE WEST OF OUR REGION. PATCHY VALLEY FOG WILL
DEVELOP OVERNIGHT...AND WILL FORECAST A COUPLE HOURS OF MVFR AT LOZ
AND SME DUE TO A CONTINUED STEADY INCREASE IN SURFACE DEWPOINTS.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...JJ
LONG TERM...GREIF/RAY
AVIATION...ABE
AREA FORECAST DISCUSSION
NWS JACKSON KY
339 PM EDT THU JUN 20 2013
.SHORT TERM...(THIS EVENING THROUGH FRIDAY NIGHT)
ISSUED AT 323 PM EDT THU JUN 20 2013
AS OF MID AFTERNOON...A RIDGE OF HIGH PRESSURE WAS CENTERED OVER
NORTHERN MEXICO AND THE SOUTHERN PLAINS WITH RIDGING EXTENDING NORTH
THROUGH THE PLAINS AND GENERAL RIDGING SOUTHEAST INTO THE GULF OF
MEXICO. MEANWHILE...A SHORTWAVE IS WORKING THROUGH THE OH VALLEY WITH
WEAK TROUGHING IN PLACE OVER THE LOWER OH VALLEY AND TN VALLEY REGION
INTO THE SOUTHEAST. AF THE SFC...HIGH PRESSURE WAS CENTERED OVER THE
NORTHEASTERN CONUS WITH RIDGING SOUTHWEST INTO THE OH VALLEY.
CONVECTION SO FAR HAS GENERALLY BEEN CONFINED TO THE NORTHERN
CUMBERLAND PLATEAU OF TN INTO THE LAKE CUMBERLAND REGION.
FOR THE REMAINDER OF THIS AFTERNOON AND INTO THIS EVENING...
CONVECTION SHOULD CONTINUE TO DEVELOP ALONG THE TN AND VA BORDERS
AS THE SHORTWAVE WORKS ACROSS THE OH VALLEY. CONVECTION SHOULD WANE
THROUGH THE EVENING WITH LOSS OF DAYTIME HEATING WITH CU DISSIPATING
DURING THAT TIME AS WELL. AREAS OF VALLEY FOG SHOULD DEVELOP TONIGHT
WITH DEWPOINTS AROUND 60 OR IN THE LOWER 60S AND A RELATIVELY WEAK
PRESSURE GRADIENT IN PLACE. SOME OF THIS WILL ALMOST CERTAINLY BECOME
DENSE IN THE RIVER VALLEYS...ESPECIALLY IN THE BIG SANDY REGION. POPS
FOR THE REMAINDER OF THE AFTERNOON INTO THE EVENING WERE RELATIVELY
UNCHANGED AS RECENT TRENDS ARE GENERALLY SUPPORTIVE OF THESE WHEN
CONSIDERED WITH RECENT MODEL GUIDANCE INCLUDING RECENT HRRR RUNS THAT
EVENTUALLY DEVELOP CONVECTION NEAR THE VA BORDER AND THEN HAVE A
COUPLE OF GENERATIONS OF IT WORKING TOWARD THE NORTHWEST OVER THE
SOUTHEASTERN COUNTIES.
THE REGION WILL BE IN A GENERAL WEAKNESS BETWEEN RIDGING OVER THE
ATLANTIC AND OVER THE MS VALLEY REGION WHILE A WEAK UPPER LEVEL LOW
IS PROGGED OVER THE SOUTHEASTERN STATES FOR FRI AND FRI NIGHT.
GENERALLY DIURNALLY DRIVEN CONVECTION IS ANTICIPATED FRI AFTERNOON
INTO FRI EVENING AS THERE ARE NO OTHER REAL TRIGGERS. SLIGHT CHANCE
POPS WERE USED FOR ALL AREAS ALONG SOUTH OF INTERSTATE 64 WITH A
LITTLE BIT OF CHANCE OVER THE HIGHEST TERRAIN ALONG THE VA BORDER.
PATCHY VALLEY FOG IS AGAIN FAVORED WITH SFC HIGH PRESSURE CENTERED TO
OUR EAST AND NORTHEAST WITH RELATIVELY HIGH DEWPOINTS AND A WEAK
PRESSURE GRADIENT. MUCH OF THE CLOUD COVER SHOULD THIN ON FRI NIGHT
WITH LOSS OF DAYTIME HEATING.
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 339 PM EDT THU JUN 20 2013
THE LONG TERM STARTS OUT ON SATURDAY WITH AN UPPER RIDGE DOMINATING
THE SOUTHEAST COAST WITH A RESIDUAL WEAK CUTOFF UPPER LOW LOCATED
NEAR THE AL-TN-GA BORDER. CONFIDENCE IN THE FORECAST IS VERY LOW
BECAUSE THE MODELS REALLY DO NOT DO VERY WELL WITH THESE RESIDUAL
LOWS THIS TIME OF THE YEAR. THE FORECAST POSITIONS CAN BE VASTLY
DIFFERENT BASED ON THE POSITION OF THE UPPER LOW...AS IT CAN BRING
WITH IT INCREASED INSTABILITY AND A GREATER CHANCE FOR
PRECIPITATION. IN GENERAL...CONDITIONS WILL BE WARM WITH LOTS OF
CONVECTIVE ACTIVITY. THE THUNDER SHOULD TEND TO HAVE AN AFTERNOON
AND EARLY EVENING MAXIMUM...HOWEVER AN ISOLATED STORM MAY CONTINUE
INTO THE OVERNIGHT HOURS. SOME OF THE STORMS MAY BECOME STRONG
HOWEVER SHOULD STAY BELOW SEVERE CRITERIA. IN PLACES WHERE
THUNDERSTORMS DO OCCUR...THERE COULD BE SOME LOCALIZED HIGH WATER
WITH DITCHES AND LOW WATER CROSSINGS RUNNING FULL DUE TO THE VERY
SLOW MOVEMENT OF THE STORMS. TEMPERATURES WILL CONTINUE TO BE VERY
SEASONAL WITH HIGH TEMPERATURES STAYING IN THE MID 80S. THIS PATTERN
SHOULD CONTINUE THROUGH THE END OF THE PERIOD.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z FRIDAY AFTERNOON)
ISSUED AT 130 PM EDT THU JUN 20 2013
SFC HIGH PRESSURE WILL BRING MAINLY VFR CONDITIONS AND LIGHT WINDS
THROUGH THE PERIOD. FOG IS AGAIN POSSIBLE FROM ABOUT 6Z ON...GENERALLY
BETWEEN 09 AND 12Z. CU NEAR 4K FT WILL CONTINUE TO DEVELOP EARLY IN
THE PERIOD...WITH ISOLATED SHOWER AND THUNDERSTORMS POSSIBLE THROUGH
ABOUT 1Z...MAINLY ALONG THE HIGHER TERRAIN BORDERING TN/VA. THIS
ACTIVITY COULD AFFECT LOZ AND SME...BUT SHOULD REMAIN SOUTH OF JKL.
ADDITIONAL CONVECTION MAY DEVELOP AROUND 16Z NEAR THE END OF THE PERIOD.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...JP
LONG TERM...JJ
AVIATION...JP
THE EXTENDED FORECAST DISCUSSION WILL BE ISSUED SHORTLY.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z FRIDAY AFTERNOON)
ISSUED AT 130 PM EDT THU JUN 20 2013
SFC HIGH PRESSURE WILL BRING MAINLY VFR CONDITIONS AND LIGHT WINDS
THROUGH THE PERIOD. FOG IS AGAIN POSSIBLE FROM ABOUT 6Z ON...GENERALLY
BETWEEN 09 AND 12Z. CU NEAR 4K FT WILL CONTINUE TO DEVELOP EARLY IN
THE PERIOD...WITH ISOLATED SHOWER AND THUNDERSTORMS POSSIBLE THROUGH
ABOUT 1Z...MAINLY ALONG THE HIGHER TERRAIN BORDERING TN/VA. THIS
ACTIVITY COULD AFFECT LOZ AND SME...BUT SHOULD REMAIN SOUTH OF JKL.
ADDITIONAL CONVECTION MAY DEVELOP AROUND 16Z NEAR THE END OF THE PERIOD.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...JP
LONG TERM...JJ
AVIATION...JP
AREA FORECAST DISCUSSION
NWS DETROIT/PONTIAC MI
958 PM EDT FRI JUN 21 2013
.UPDATE...
CLOUD SHIELD FROM THE LONG-LIVED MCS...NOW POSITIONED OVER SW
INDIANA WHITTLING INTO THE DEEP INSTABILITY RESERVOIR...HAS
QUICKLY DISSIPATED OVER SOUTHEAST MICHIGAN IN THE BROAD UPPER-
LEVEL ANTI-CYCLONIC FLOW. RETURN DEEP THETA-E ADVECTION IS
ALREADY EVIDENT...IN THE FORM OF FRESH SHOWER DEVELOPMENT...NEAR
LAKE MICHIGAN. THIS INITIAL FEATURE IS EXPECTED TO SLIDE EAST AND
SLOWLY WASH OUT IN THE POST-MIDNIGHT HOURS. WHILE THIS OCCURS
GREATER THETA-E ADVECTION IN THE 925-850MB LAYER...OWING FROM AN
INCREASING NOCTURNAL LOW-LEVEL JET...WILL FILTER INTO THE LOWER
PENINSULA LATE TONIGHT. LATEST RAP SOLUTIONS INDICATE 0-1KM MLCAPE
VALUES CLIMBING TO NEAR 1KJ/KG BY DAYBREAK AND INCREASE FROM THERE
THROUGH THE MORNING HOURS. THE SHARP INSTABILITY GRADIENT WILL
QUICKLY TAKE RESIDENCE ACROSS AREAS ALONG AND NORTH OF I-69.
EXPECT NEW CONVECTION TO CONTINUE TO CYCLE ALONG THE SURGE OF
INSTABILITY ACROSS WISCONSIN AND WESTERN LOWER MICHIGAN AS WARM
FRONTAL DYNAMICS WILL AID IN FORCING ASCENT. FARTHER UPSTREAM
ORGANIZED CONVECTION SHOULD CONTINUE ALONG THE SHARP INSTABILITY
GRADIENT OVER SOUTHEAST MINNESOTA AND CENTRAL WISCONSIN. EXPECT
SOME OF THIS ACTIVITY TO CHURN EAST ALONG THE WELL DEFINED
INSTABILITY GRADIENT THROUGHOUT THE NIGHT AND INTO SATURDAY
MORNING.
&&
.AVIATION...ISSUED 723 PM EDT FRI JUN 21 2013
//DISCUSSION...
MAIN POINT OF INTEREST THIS EVENING IS AN ENHANCED WIND FIELD
HARNESSED TO THE RESIDUAL LEFTOVERS FROM THE UPSTREAM CONVECTIVE
SYSTEM. THERE WILL BE A COUPLE OF HOURS WHERE WINDS WILL GAIN A GUST
COMPONENT BEFORE SUCCUMBING TO NEAR SURFACE STABILIZATION.
THUNDERSTORM PROSPECTS THEN BECOME THE NEXT ORDER OF BUSINESS. THE
ESTABLISHMENT OF MODEST INSTABILITY ACROSS THE SOUTHERN GREAT LAKES
LATE TONIGHT WILL AFFORD AN OPPORTUNITY FOR THE VIGOROUS
THUNDERSTORM COMPLEX OVER MINNESOTA TO CONTINUE EAST INTO THE
REGION. THE GREATEST CHANCES FOR THUNDERSTORMS WILL BE ACROSS THE
NORTHERN TERMINAL LOCATIONS CLOSER TO THE INSTABILITY GRADIENT.
FOR DTW...REMNANT SHOWER ACTIVITY NEAR BTL CONTINUES TO DECREASE IN
COVERAGE AND WILL LIKELY DRY UP COMPLETELY BEFORE ARRIVING. THERE IS
A SMALL TIME WINDOW TO TAP INTO A WELL MIXED SURFACE LAYER IN THE
VICINITY OF THE DECAYING LINE OF SHOWER BEFORE NOCTURNAL DECOUPLING
COMMENCES. OTHERWISE...LEADING ZONE OF INSTABILITY WILL AT A MINIMUM
PRODUCE AN ENHANCED CLOUD FIELD AROUND 5KFT AROUND SUNRISE SATURDAY.
CURRENT INDICATIONS ARE THAT THE ORGANIZED UPSTREAM CONVECTION WILL
REMAIN NORTH OF THE DETROIT AREA TERMINALS...CLOSER TO THE NEAR
SURFACE WARM FRONT.
//DTW THRESHOLD THREATS...
* MODERATE CONFIDENCE FOR A BRIEF PERIOD OF CEILINGS AT 5KFT
SATURDAY MORNING.
* LOW CONFIDENCE IN THUNDERSTORMS SATURDAY MORNING.
&&
.PREV DISCUSSION...ISSUED 347 PM EDT FRI JUN 21 2013
SHORT TERM...TONIGHT
SOUTHEAST MICHIGAN REMAINS ON THE OUTER FRINGE OF THE UPPER LEVEL
RIDGE CENTERED OVER MISSOURI (SECOND RIDGE CENTER OVER MID
ATLANTIC)...WHICH MAKES FOR A DIFFICULT FORECAST AS 500 MB HEIGHT
HOVERS AROUND THE NORMALLY CRITICAL VALUE OF 588 DAM.
NONE-THE-LESS...700 MB TEMPS REMAIN BELOW 10 C THROUGH
TONIGHT...WHICH SUGGEST ACTIVITY IS POSSIBLE/NOT FULLY CAPPED.
THE MASSIVE AND LONG LIVED MCS WHICH DEVELOPED OVER THE WESTERN
GREAT LAKES THIS MORNING CONTINUES TO WEAKEN...WITH REMNANT 500 MB
LOW/TROUGH TRACKING THROUGH NORTHERN LOWER MICHIGAN EARLY THIS
EVENING. LATEST RADAR TRENDS SUGGEST A FEW SHOWERS AND POSSIBLE
THUNDERSTORMS MAY SURVIVE THE TRIP ACROSS THE STATE...AS THERE IS
SOME MODEST CAPES (SB CAPES OF 1000 J/KG)/INSTABILITY THE RAIN
COOLED AIRMASS WILL BE MOVING INTO. ON THE FLIP SIDE...DEW PTS ARE
MIXING DOWN INTO THE 50S ACROSS NORTHERN INDIANA/NW OHIO AND INTO
PARTS OF SOUTHERN LOWER MICHIGAN...INDICATIVE OF THE 850-700 MB
THETA-E TROUGH ASSOCIATED WITH THE RIDGE CENTER OVER THE MID
ATLANTIC STATES...AND THUS THE DIRECTION THE FORECAST IS SKEWED WITH
JUST SLIGHT CHANCE POPS SOUTH TO CHANCE POPS NORTH.
THE QUESTION THEN BECOMES WHAT TO DO WITH TONIGHT...AS WISCONSIN LOW
TRACKS NORTHEAST...ALLOWING FOR A DECENT 850 MB JET OF 40+ KNOT TO
SET UP OVER NORTHERN LOWER MICHIGAN THIS EVENING. GOOD
DESTABILIZATION TO REDEVELOP OVER THE WESTERN GREAT LAKES...WITH
ANOTHER MCS DEVELOPING OVER THE EASTERN DAKOTAS THIS AFTERNOON...AND
IT CERTAINLY IS POSSIBLE THIS COMPLEX WILL ARRIVE IN A WEAKENED
STATE OVER LOWER MICHIGAN LATER TONIGHT...DESPITE THE 12Z NAM
INDICATING DISSIPATION OVER WISCONSIN THIS EVENING. EVEN IF THIS
DOES NOT OCCUR...STILL A CHANCE THE LOW LEVEL JET WILL TRIGGER A FEW
SHOWERS/THUNDERSTORMS WITH MOISTURE AXIS MOVING
OVERHEAD...ESPECIALLY AS ONE HEADS NORTH TOWARD SAGINAW BAY...CLOSER
TO THE REMNANT WEAK FRONTAL BOUNDARY AND BETTER MOISTURE TRANSPORT.
WITH INCREASING LOW LEVEL MOISTURE...MINS IN THE 60S ARE EXPECTED.
LONG TERM... SATURDAY THROUGH FRIDAY
EVOLUTION OF CONVECTION OVER THE MIDWEST AND GREAT LAKES REMAINS THE
PRIMARY FORECAST CHALLENGE THROUGH THE WEEKEND AS A MID SUMMER AIR
MASS SPREADS OVER THE REGION. SATELLITE IMAGERY AND MODEL ANALYSIS
FIELDS INDICATE THE CONVECTIVE COMPLEX FROM THIS MORNING YIELDED A
SUBSTANTIAL MCV NOW OVER THE NORTHERN GREAT LAKES BUT WHICH WILL
MOVE EAST IN TIME FOR EITHER THE ONGOING NORTHERN PLAINS
CONVECTION TO MOVE EASTWARD OR FOR A NEW ROUND OF NOCTURNAL
DEVELOPMENT OVER THE UPPER MIDWEST TONIGHT. THE GENESIS REGION
WILL BE FARTHER EAST COMPARED TO LAST NIGHT, MIGRATING WITH THE
LARGE SCALE SURFACE TROUGH FROM THE NORTHERN PLAINS/DAKOTAS INTO
MINNESOTA/NORTHERN WISCONSIN. EXPECT A RESURGENT LOW LEVEL JET TO
FORCE NEW CONVECTION BY LATE THIS EVENING, OR SUPPORT THE ONGOING
STORMS MOVING IN FROM THE DAKOTAS, EITHER OF WHICH WILL HAVE A
CHANCE TO REACH CENTRAL/SE MICHIGAN DURING SATURDAY MORNING.
INITIATION/PERSISTENCE OF EVENING CONVECTION WILL BE FAVORED ALONG
EDGE OF THE MID LEVEL CAP, SUPPORTED BY OBSERVATIONS TO BE ROUGHLY
IN THE 8-10C RANGE AT 700 MB AND AROUND 18C AT 850 MB. THIS, ALONG
WITH A WESTERLY MEAN FLOW WILL SET UP A GENERAL WEST TO EAST
DEVELOPMENT OF STORMS INTO SATURDAY MORNING. LOWER MICHIGAN WILL
BE MORE RECEPTIVE TO MCS PERSISTENCE BY THEN DUE TO INCREASED
POTENTIAL INSTABILITY IN THE WARM SECTOR OVER THE REGION, AT LEAST
COMPARED TO THIS MORNING, BUT WITH THE INSTABILITY AXIS GENERALLY
WEAKENING FROM WEST TO EAST OVER THE GREAT LAKES. THE KEY TO
COVERAGE IN SE MICHIGAN MIGHT BE TIED TO THE INSTABILITY
GRADIENT/CAP TAKING ON MORE OF WEST TO EAST CONFIGURATION AS THE
WARM FRONT MOVES INTO THE NORTHERN GREAT LAKES, WHICH FAVORS THE
TRI CITIES AND NORTHERN THUMB WITH THE GREATEST CHANCE OF STORMS.
SEVERE WEATHER POTENTIAL REMAINS ON THE LOW SIDE AS A MATURE
COMPLEX WILL BE POSSIBLE BUT, AS MENTIONED ABOVE, EXPECTED TO BE
MOVING INTO WEAKER ENVIRONMENT OF INSTABILITY AND MID LEVEL LAPSE
RATES. BULK SHEAR IN THE 0-6 KM LAYER IS ALSO UNFAVORABLE AT
GENERALLY LESS THAN 20 KNOTS AS THE LARGER SCALE RIDGE BUILDS OVER
THE REGION.
CONDITIONS WILL BECOME INCREASINGLY CAPPED FOR THUNDERSTORM ACTIVITY
DURING SATURDAY AFTERNOON THROUGH SUNDAY. AFTER NOCTURNAL CONVECTION
EXITS/DISSIPATES SATURDAY MORNING, MODERATE SOUTHWEST LOW LEVEL FLOW
WILL DISSIPATE ANY LINGERING OUTFLOW BOUNDARIES AND WORK AGAINST
LAKE BREEZE FORMATION/INLAND PENETRATION. ALL OF THIS WILL OCCUR AS
THE UPPER LEVEL RIDGE BUILDS OVER LOWER MICHIGAN AND REINFORCES WARM
AIR THROUGH THE MID LEVELS. THE NEW 12Z RUNS ARE IN GOOD GENERAL
AGREEMENT ON THE CHARACTER OF THE RIDGE WITH 500 MB HEIGHT BUILDING
INTO THE 588-591 RANGE BY SATURDAY NIGHT INTO SUNDAY. THIS WILL
SUPPORT THE RECENTLY ADVERTISED HEAT AND HUMIDITY FOR THE REST OF
THE WEEKEND. SURFACE DEWPOINT PUSHING 70F WILL BOOST HEAT INDEX INTO
THE LOWER 90S SATURDAY AFTERNOON AND TOWARD THE MID 90S SUNDAY WITH
GREATER CONFIDENCE THAT CLOUD COVER WILL HAVE MINIMAL IMPACT ON
AFTERNOON MAX TEMPS.
THE LARGE SCALE PATTERN WILL SUPPORT PERSISTENCE OF WARM AND HUMID
CONDITIONS INTO NEXT WEEK. THE MAIN SOURCE OF FORECAST UNCERTAINTY
DURING MONDAY AND TUESDAY WILL BE WITH THE EVOLUTION OF A WEAK UPPER
LEVEL CIRCULATION NOW OVER THE SOUTHEAST STATES. GLOBAL MODELS
INDICATE THIS FEATURE SLOWLY DRIFTING INTO THE WESTERLIES AS A NEW
SHORT WAVE SLIDES INTO NORTHERN ONTARIO. THE ABSORPTION OF THE UPPER
CIRCULATION OVER THE EASTERN GREAT LAKES WILL COMBINE WITH THE
POTENTIAL FOR A DECAYING FRONTAL BOUNDARY TO SETTLE OVER THE REGION
AND REQUIRE A CONTINUED CHANCE MENTION OF SHOWERS AND STORMS. THERE
REALLY IS NO CONVINCING MODEL SOLUTION THAT OFFERS A SIGNIFICANT
CHANGE OF AIR MASS DURING THE SECOND HALF OF NEXT WEEK UNTIL
PERHAPS FRIDAY. THE LONG WAVE PATTERN IS SHOWN TO RETROGRADE
ENOUGH BY THEN AND OPEN THE DOOR ON A CANADIAN AIR MASS HEADING
INTO NEXT WEEKEND.
MARINE...
GENERALLY LIGHT SOUTHERLY WINDS WILL CONTINUE THROUGH THE
WEEKEND...LEADING TO UNSTABLE ATMOSPHERIC CONDITIONS WHICH COULD
TRIGGER THUNDERSTORMS FROM TIME TO TIME. OUTSIDE OF THUNDERSTORM
ACTIVITY, HIGHLY STABLE CONDITIONS CREATED BY THE WARM AIR OVER THE
COOL LAKE WATER WILL MAINTAIN A MUTED RESPONSE TO THE WAVE GROWTH.
&&
.DTX WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LAKE HURON...NONE.
LAKE ST CLAIR...NONE.
MI WATERS OF LAKE ERIE...NONE.
&&
$$
UPDATE.......MANN
AVIATION.....MANN
SHORT TERM...SF
LONG TERM....BT
MARINE.......SF
YOU CAN OBTAIN YOUR LATEST NATIONAL WEATHER SERVICE FORECASTS ONLINE
AT WWW.WEATHER.GOV/DETROIT (ALL LOWER CASE).
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
435 PM EDT THU JUN 20 2013
.SHORT TERM...(THIS EVENING THROUGH FRIDAY)
ISSUED AT 431 PM EDT THU JUN 20 2013
UPPER AIR PATTERN FEATURES DEEP TROUGHING OVER NORTHWEST CONUS WITH
RIDGING DOWNSTREAM OVER NORTHERN PLAINS. SFC FRONT WITH DRIER AIR IS
WORKING ACROSS DAKOTAS WITH WEAK SFC LOW OVR NCNTRL SD BTWN KBIS AND
KABR. BASED ON SFC OBS AND VIS SATELLITE APPEARS WARM FRONT EXTENDS
FROM SFC LOW ACROSS CNTRL MN AND INTO NORTHWEST WI. NOT MUCH OF A
TEMP GRADIENT AT H85 BUT RIBBON OF HIGHER H85-H7 DWPNT ALONG WITH
H85 CONVERGENCE FROM NORTHERN MN ACROSS UPR MICHIGAN IS SERVING AS
FOCUS WAVE AFTER WAVE OF SCT SHRA/ISOLD TSRA. NO STRONG TSTM THOUGH
AS CAPE AVAILABLE OVR THE AREA IS BLO 1000 J/KG. DEEP LAYER SHEAR IS
MARGINAL AS WELL...MAYBE UP TO 30 KTS. STRONGEST CONVECTION TODAY
HAVE HAD LIGHTNING BUT HAVE REALLY SHOWN LITTLE TILT OWING TO THE
LIMITED INSTABILITY/SHEAR.
BASED ON WV LOOP/LIGHTNING AND RUC ANALYSIS...DOES SEEM THAT THERE
IS ONE WEAKER SHORTWAVE OVER NORTHWEST WI...ANOTHER NEAR THE DLH
AREA...AND A STRONGER WAVE LIFTING ENE ACROSS NORTHEAST ND. EXPECT
ISOLD-SCATTERED SHRA AND TSRA OVR CWA THROUGH EVENING...ESPECIALLY
NORTHERN HALF...AS THESE WAVES SLIDE THROUGH ALONG THE BOUNDARY AT
H85. OVERALL...LIMITED INSTABILITY SHOULD PRECLUDE STRONGER STORMS
THIS EVENING OVR MUCH OF CWA. EXCEPTION MAY BE IN FAR SW VCNTY OF
IWD AS MLCAPE BUILDING UP OVER 1000J/KG JUST TO SOUTHWEST OF WEST
CWA AND SWRLY STORM MOTION COULD RESULT IN STRONGER STORM WITH GUSTY
WINDS AND HAIL. THUS FAR NO REAL INDICATIONS OF THIS WITH UPSTREAM
STORMS BUT IT IS SOMETHING TO WATCH.
LATER TONIGHT...MAIN QUESTION IS WHAT WILL OCCUR WITH UPSTREAM
CONVECTION. IN A NUTSHELL...APPEARS THAT IF PRIMARY AREA OF
CONVECTIVE DEVELOPING THROUGH EARLY EVENING OCCURS ALONG AND EAST OF
SFC LOW...850-300MB THICKNESS/ORIENTATION OF HIGHEST MUCAPE/FORWARD
PROPAGATING CORFIDI VECTORS POINT TO MAIN TRACK OF SHRA/TSRA COMPLEX
OR BONIFIDE MCS MAINLY STAYING SOUTH OF CWA...WOULD BE CLOSE IN THE
SOUTHWEST CWA THOUGH. ON THE OTHER HAND...IF CONVECTION OVR
NORTHEAST ND CONTINUES TO DRIFT ACROSS RIDGE TOP IT COULD ADVECT
AND/OR SPUR ON ADDITIONAL SHRA/TSRA OVERNIGHT IN NORTHERN MN AND
BASED ON 850-300MB THICKNESSES...SHRA/TSRA WOULD TRACK INTO FAR
WESTERN UPR MICHIGAN 08Z-12Z. INCREASING SFC-ML CAPES AND 0-1KM
SHEAR UP TO 20 KTS AND BOW-LIKE APPEARANCE FROM VARIOUS HIGHER
RESOLUTION MODELS INDICATE IF THIS CONVECTION IMPACTS WESTERN CWA
THERE COULD BE STRONG WIND GUSTS. WITH ALL THE CLOUD COVER AND
POSSIBLE SHRA/TSRA WILL BE A WARM NIGHT WITH LOWS IN THE MID 50S
EAST AND STAYING ABOVE 60 DEGREES OVER THE WEST.
FOR FRIDAY...CONDITIONAL FORECAST FOR SURE. IF THE SHRA/TSRA ARE
AROUND IN THE MORNING...EXPECT A GENERAL LULL LATE MORNING INTO MOST
OF THE AFTN DUE TO THE SUBSIDENCE IN WAKE OF THE CONVECTION. MIXING
TO H9 WOULD SUPPORT HIGHS WELL INTO THE 70S IF NOT REACHING 80 WITH
ENOUGH SUNSHINE. AFTN INSTABILITY AND WARM FRONT/OUTFLOW IN THE VCNTY
COULD LEAD TO MORE DEVELOPING SHRA/TSRA MID-LATE AFTN. LOW CHANCE
POPS FOR ALL AREAS AFTER THE MAIN SHRA/TSRA CHANCES IN THE MORNING.
BEST CHANCE IN THE AFTN WOULD PROBABLY BE IN THE WEST/SOUTHWEST CWA
WITH BETTER SHOT OF EARLIER CLEARING/WARMER TEMPERATURES. HUMID
CONDITIONS THAT HAVE DEVELOPED TODAY WILL CONTINUE THROUGH FRIDAY
WITH DWPNTS STAYING AT OR ABOVE 60 IN MANY AREAS.
.LONG TERM...(FRIDAY NIGHT THROUGH THURSDAY)
ISSUED AT 431 PM EDT THU JUN 20 2013
FRI NIGHT...
AFTER THE EXPECTED AREA OF SHRA/TSRA EXITS THE ERN CWA FRI
EVENING... CONSENSUS OF MODELS SUGGEST PERHAPS A BREAK IN SHRA/TSRA
BY LATE FRI EVENING BEFORE MORE CONVECTION DEVELOPS OVER THE UPPER
MS VALLEY ALONG THE 850 MB WARM FRONT. THE FCST REFLECTS MODEL
TRENDS THAT KEEP THE FOCUS FOR CONVECTIVE DEVELOPMENT WITH THE
GREATEST INSTABILITY AND NOSE OF THE LLJ FARTHER SOUTH COMPARED TO
EARLIER RUNS.
SATURDAY AND SUNDAY...
AS THE MID LEVEL RIDGE BUILDS TO THE EAST...SW FLOW PATTERN WILL
ALLOW THE 850 MB WARM FRONT TO PUSH TO THE NORTH WITH WARM AND HUMID
AIR BECOMING ENTRENCHED OVER THE REGION. EVEN THOUGH THE MODELS HINT
AT POTENTIAL FOR A SHORTWAVE TROUGH MOVING OUT OF THE PLAINS TOWARD
NW ONTARIO SAT INTO SAT EVENING...UNCERTAINTY WITH THE
TIMING/POSITION OF THIS FEATURES AND THE IMPACT ON CONVECTIVE
DEVELOPMENT IS HIGH. WITH THE FOCUS FOR MOISTURE/LOW LEVEL THETA-E
ADVECTION SHIFTING FROM THE UPPER MS VALLEY TOWARD THE AREA...POPS
INCREASE INTO THE WRN CWA BY LATE AFTERNOON AND ACROSS UPPER
MICHIGAN SATURDAY NIGHT. WITH MLCAPE/MUCAPE VALUES INCREASING AT
LEAST INTO THE 1K-2K J/KG RANGE...THERE WILL BE A GREATER POTENTIAL
FOR STRONGER STORMS. THE MAIN HAZARD WILL BE HEAVY RAIN AS PWAT
VALUES CLIMB TO 1.5 TO 1.8 INCHES (150-180 PCT OR NORMAL).
WITH THE RIDGE BUILDING INTO THE AREA SUNDAY...CIN WILL INCREASE
WITH 700 MB TEMPS INTO THE 10C-12C RANGE. SO...TEMPS WILL CLIMB WELL
ABOVE NORMAL INTO THE 80S AND CONVECTION POTENTIAL WILL DECREASE.
HOWEVER...SHRA/TSRA MAY INCREASE AGAIN BY SUNDAY NIGHT AS A STRONGER
SHRTWV HELPS FLATTEN THE RIDGE AND BRINGS A WEAK SFC TROUGH INTO THE
REGION.
MON-THU...
THERE MAY BE DRIER PERIOD WITH A WEAK MID LEVEL AND SFC RIDGE INTO
THE AREA MON INTO TUE. HOWEVER...CONFIDENCE REMAINS LOW WITH THE
RETROGRADING RIDGE LEADING TO A MORE ZONAL PATTERN. AS THE RIDGE
BUILDS OVER THE WRN CONUS...A MORE NW FLOW PATTERN WILL STILL KEEP
POTENTIAL FOR SHRA/TSRA GOING. TEMPS SHOULD TRANSITION BACK TOWARD
MORE NORMAL VALUES.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z FRIDAY AFTERNOON)
ISSUED AT 158 PM EDT THU JUN 20 2013
SHRA/TSRA EXTENT AND TIMING ARE FAIRLY UNCERTAIN AS MULTIPLE WAVES
OF SHRA/TSRA COULD IMPACT ALL TAF SITES THROUGH MIDDAY FRIDAY. BASED
ON RECENT RADAR AND A WESTERLY STORM MOTION...EXPECT BEST CHANCE OF
SHRA/TSRA INTO EARLY EVENING. OVERALL CIGS WILL CONTINUE TO BE VFR
BUT VSBY MAY BRIEFLY DIP TO IFR IN HEAVIER DOWNPOURS. A LULL IS THEN
POSSIBLE UNTIL LATE TONIGHT. DURING THAT QUIETER PERIOD HAVE KEPT
LOWER CEILING/VIS AT CMX...AS FOG SHOULD BE ABLE TO PUSH UP THE HILL
AND LOWER CONDITIONS TO IFR FROM 05-10Z. LATE TONIGHT ANOTHER ROUND
OF SHRA/TSRA COULD MOVE INTO FAR WESTERN UPR MICHIGAN THEN SLOWLY
SLIDE INTO CNTRL UPR MICHIGAN LATE FRIDAY MORNING. CONFIDENCE IN
SHRA/TSRA SPECIFICS IS LOW BUT DID INCLUDE MENTION OF SHRA AND VCNTY
TSRA FOR IWD AND CMX. STORMS LATE TONIGHT INTO FRIDAY MORNING MAY
PRODUCE STRONG WIND GUSTS...BUT THIS IS UNCERTAIN AT THIS POINT.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 431 PM EDT THU JUN 20 2013
FOG...AND ANY STRONGER STORMS /WITH WINDS AND/OR SMALL HAIL/ WILL BE
THE MAIN HAZARDS THROUGH THE WEEKEND. OTHERWISE WINDS SHOULD REMAIN
AT OR BELOW 25KTS.
A TROUGH OF ACROSS LAKE SUPERIOR WILL...DEEPEN FRIDAY NIGHT...AND
AGAIN SUNDAY THROUGH MONDAY. THIS WILL BE IN RESPONSE TO AN
ELONGATED AREA OF LOW PRESSURE STRETCHING FROM SOUTHWESTERN CANADA
THROUGH EASTERN COLORADO. EXPECT THE AREA OF LOW PRESSURE TO
CONSOLIDATE ACROSS THE CENTRAL PLAINS ON SATURDAY...BEFORE SHIFTING
INTO MANITOBA ON SUNDAY...AND EXITING EASTWARD THROUGH ONTARIO ON
MONDAY.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...JLA
LONG TERM...JLB
AVIATION...JLA
MARINE...JLB
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
455 AM EDT THU JUN 20 2013
.SHORT TERM...(THIS EVENING THROUGH THURSDAY)
ISSUED AT 429 PM EDT WED JUN 19 2013
WV IMAGERY AND RUC ANALYSIS INDICATED WNW MID/UPPER LEVEL FLOW
THROUGH THEN NRN GREAT LAKES BETWEEN A TROUGH OVER ERN CANADA AND A
RIDGE OVER THE PLAINS. SCT SHRA AND ISOLD TSRA HAD DEVELOPED NEAR
CYRL ON THE TAIL OF A SHORTWAVE TROUGH THROUGH NW ONTARIO. AN
UPSTREAM SHRTWV WAS ALSO LOCATED OVER ERN SD. AT THE SFC...SRLY
WINDS HAD INCREASED BETWEEN HIGH PRES OVER THE ERN GREAT LAKES AND A
TROUGH EXTENDING INTO ND FROM LOW PRES W OF JAMES BAY. LOW LEVEL
MOISTURE WAS ONLY SLOWLY INCREASING WITH DEWPOINTS CLIMBING TO NEAR
50F OVER THE WEST.
TONIGHT...EVEN THOUGH THE FORCING WITH THE NW ONTARIO SHRTWV WILL
REMAIN NORTH OF THE CWA...MODELS SUGGEST THAT THE SHRA AND POSSIBLY
SOME TSRA WILL DEVELOP LATER THIS EVENING NW OF LAKE SUPERIOR AND
SLIDE INTO THE WRN CWA OVERNIGHT. MOISTURE TRANSPORT AND THE
POSITION OF THE 850-700 MB FRONTAL ZONE FAVORS GREATER PCPN
CHANCES/COVERAGE OVER NW LAKE SUPERIOR INTO MAINLY THE NW CWA.
MUCAPE VALUES ARE EXPECTED TO BE HIGH ENOUGH FOR ELEVATED TSRA
DEVELOPMENT.
THURSDAY...THE COMBINATION OF INCREASING MOISTURE
TRANSPORT...DAYTIME HEATING AND THE SD SHRTWV SHOULD BRING
INCREASING SHRA/TSRA COVERAGE ACROSS THE CWA. ALTHOUGH INSTABILITY
WILL BE MARGINAL FOR STRONGER STORMS WITH MLCAPE VALUES INTO THE
500-1000 J/KG RANGE...AND A RELATIVELY NARROW CAPE PROFILE....SOME
STORMS WITH SMALL HAIL AND GUSTY WINDS TO 35 MPH MAY BE POSSIBLE.
.LONG TERM...(FRIDAY THROUGH WEDNESDAY)
ISSUED AT 452 AM EDT THU JUN 20 2013
CONVECTION WILL MAKE FOR A CHALLENGING AND UNCERTAIN FORECAST FRI
THROUGH AT LEAST THE WEEKEND.
AN UPPER RIDGE WILL BUILD E OVER THE AREA FRIDAY THROUGH THE
WEEKEND. AT THE SFC...A LOW WILL REMAIN FAIRLY STATIONARY OVER THE
CENTRAL PLAINS AND EXTENDING FROM THE LOW A WARM FRONT WILL BECOME
POSITIONED ACROSS THE UPPER MS VALLEY AND UPPER GREAT LAKES REGION
THROUGH THE WEEKEND. CONFIDENCE REMAINS LOW WITH THE EXACT
TRACK/TIMING OF CONVECTIVE COMPLEXES DEVELOPING AND MOVING ALONG OR
NEAR THE WARM FRONT. MODELS CONTINUE TO SHOW DIFFERING SCENARIOS FOR
CONVECTIVE DEVELOPMENT AND MOVEMENT...WHICH DEPEND LARGELY ON
NORTHWARD EXTENT OF WARM FRONT. THE GFS AND EVEN THE NAM ARE MOST
AGGRESSIVE WITH NORTHWARD EXTENT OF WARM FRONT ON FRI BRINGING IT AS
FAR NORTH AS LAKE SUPERIOR OR NRN UPPER MI WHILE THE REG GEM AND
ECMWF KEEP THE WARM FRONT JUST TO THE SOUTH OVER WI. NOT
SURPRISINGLY...THE GFS AND NAM INDICATE A CONVECTIVE COMPLEX
BUILDING CLOSER TO MN/CANADIAN BDR TONIGHT WITH MUCH OF THE HEAVIER
PCPN/STORMS MOVING OVER LAKE SUPERIOR AND N CNTRL UPPER MI LATE
TONIGHT INTO FRIDAY. MEANWHILE...THE REGIONAL GEM AND ECMWF SHOW
STORM COMPLEX DEVELOPING CLOSER TO CENTRAL MN AND THEN MOVING ESE IN
LINE WITH FORWARD PROPAGATING CORFIDI VECTORS AND 850-300 MB
THICKNESS LINES ACROSS THE CWA LATE TONIGHT AND FRIDAY WITH THE
HEAVIEST PCPN AND STRONGEST STORMS STAYING CLOSER TO THE WI BDR.
WILL TEND LEAN CLOSER TO THE REG GEM AND ECMWF SOLNS KEEPING THREAT
OF HEAVIER PCPN AND STRONGEST STORMS CLOSER TO THE WI BDR ON FRIDAY
WHICH ALSO FITS WELL WITH SPC DAY2 OUTLOOK. THERE COULD BE A SLIGHT
RISK OF SVR STORMS ON FRIDAY ALONG THE WI BDR WHERE THE GEM AND NAM
INDICATES MLCAPE VALUES BTWN 1000-1500 J/KG. GFS MLCAPE VALUES OF
2000-3000 J/KG OVER THE WRN HALF OF THE CWA ON FRI LOOK OVERBLOWN
WHICH MAY BE DUE IN PART TO THE FARTHER NORTHWARD EXTENT OF THE WARM
FRONT. REGARDLESS...WILL HIGHLIGHT LIKELY TO CATEGORICAL POPS FOR
SHRA/TSRA ACROSS THE CWA ON FRI WITH GREATEST POPS AND GREATEST
THREAT FOR SVR STORMS OVER SCNTRL CWA. THERE IS A POTENTIAL FOR
HEAVY RAIN WITH THE THUNDERSTORMS AS PWATS WILL BE 150-180 PERCENT
OF NORMAL.
FRI NIGHT...AFTER FRI STORM COMPLEX EXITS THE ERN CWA FRI EVENING...
CONSENSUS OF MODELS SUGGEST PERHAPS A BREAK IN CONVECTION BY LATE
FRI EVENING BEFORE MORE CONVECTION FIRES FRI NIGHT OVER CNTRL MN AT
NOSE OF 30 KT 8H JET AND THEN MOVES EAST ACROSS NRN WI INTO SCNTRL
UPPER MI LATE FRI NIGHT/EARLY SAT. GIVEN INCREASED CONFIDENCE IN
MODELS WILL HIGHLIGHT HIGHER POPS SCNTRL FOR LATE FRI NIGHT/EARLY
SAT.
MODELS SHOW EVEN GREATER UNCERTAINTY WITH CONVECTIVE EVOLUTION SAT
INTO SUN SO WILL LIKELY CONTINUE TO CARRY CHC POPS DURING THIS TIME
FRAME. ECMWF AND GEM-NH SUGGEST THERE IS A POTENTIAL FOR ANOTHER
STORM COMPLEX TO MOVE THROUGH THE AREA SAT NIGHT INTO SUNDAY AS
ANOTHER SHORTWAVE RIPPLES THROUGH THE MID-LVL RDG...SO WILL INCLUDE
HIGHER CHC POPS FOR THE SAT NIGHT AND SUN TIME PERIODS. FCST
CONFIDENCE CONTINUES TO WANE FOR THE EARLY TO MIDDLE PART OF NEXT
WEEK AS MEDIUM RANGE MODELS DISPLAY POOR CONTINUITY AND AGREEMENT ON
TIMING OF SHORTWAVE FEATURES. HOWEVER...IT DOES APPEAR THAT CHC POPS
FOR SHRA/TSRA WILL BE WARRANTED THROUGH MUCH OF THE PERIOD AS
PERIODIC SHORTWAVES WORK ON THE WARM AND HUMID AIRMASS WHICH WILL
REMAIN IN PLACE THROUGH AT LEAST TUE.
WITH MODEL CONSENSUS 18-20C 8H TEMPS OVER THE AREA FROM SAT
AFTERNOON THROUGH TUESDAY...EXPECT VERY WARM AND MUGGY CONDITIONS TO
PERSIST FROM THE WEEKEND INTO THE EARLY PORTION OF NEXT WEEK. WOULD
NOT BE SHOCKED TO SEE INLAND HIGHS...ESPECIALLY OVER THE WRN CWA IN
A WEAK TO MODERATE S-SW FLOW...TO RISE WELL INTO THE 80S AND PERHAPS
EVEN PUSH 90F AT A FEW LOCATIONS EVEN WITH THE PERIODS OF CONVECTION
FCST.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z THURSDAY NIGHT)
ISSUED AT 1209 AM EDT THU JUN 20 2013
OVERNIGHT...ATTENTION TURNS TO SFC TROF DROPPING S TOWARD THE UPPER
LAKES IN ASSOCIATION WITH SHORTWAVE CURRENTLY PASSING THRU NRN
ONTARIO. SCT SHRA AND DIMINISHING TSRA HAVE BEEN OCCURRING
ALONG/AHEAD OF TROF...AND SOME OF THOSE SHRA WILL HOLD TOGETHER AND
AFFECT KCMX OVERNIGHT AND THEN POSSIBLY KIWD/KSAW THIS MORNING.
CONFIDENCE IN SHRA OCCURRING AT KIWD/KSAW IS LOWER THAN AT KCMX...SO
ONLY VCSH WAS UTILIZED AT THOSE 2 TERMINALS. DESPITE -SHRA...INITIAL
DRIER AIR AT THE LOW-LEVELS SHOULD RESULT IN VFR CONDITIONS INTO THE
MORNING. HOWEVER...WILL NEED TO WATCH KCMX AS ANY UPSLOPE WIND OFF
THE LAKE COULD RESULT IN LOWER CLOUDS/FOG POSSIBLY FORMING THIS
MORNING. THIS AFTN...DAYTIME HEATING SHOULD GENERATE SCT SHRA/TSRA
ACROSS UPPER MI WITH BETTER POTENTIAL AT KIWD/KSAW. THERE IS LIMITED
CONFIDENCE IN PCPN ACTUALLY OCCURRING AT A TERMINAL...SO ONLY VCTS
WAS INCLUDED IN FCST. IF SHRA/TSRA OCCUR AT KIWD/KSAW...MVFR
CONDITIONS WOULD LIKELY ACCOMPANY PCPN. SCT CONVECTION SHOULD END BY
EVENING. DURING THE EVENING...COMBINATION OF A COOL EASTERLY UPSLOPE
WIND OFF THE LAKE INTO HIGHER DWPT AIR OVER THE KEWEENAW MAY RESULT
IN FOG/STRATUS DEVELOPING AT KCMX.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 354 AM EDT THU JUN 20 2013
FOG...AND ANY STRONGER STORMS /WITH WINDS AND/OR SMALL HAIL/ WILL BE
THE MAIN THREATS THROUGH THE WEEKEND. OTHERWISE WINDS SHOULD REMAIN
AT OR BELOW 25KTS.
A TROUGH OF ACROSS LAKE SUPERIOR WILL...DEEPEN FRIDAY NIGHT...AND
AGAIN SUNDAY THROUGH MONDAY. THIS WILL BE IN RESPONSE TO AN
ELONGATED AREA OF LOW PRESSURE STRETCHING FROM SOUTHWESTERN CANADA
THROUGH EASTERN COLORADO. EXPECT THE AREA OF LOW PRESSURE TO
CONSOLIDATE ACROSS THE CENTRAL PLAINS ON SATURDAY...BEFORE SHIFTING
INTO MANITOBA ON SUNDAY...AND EXITING EASTWARD THROUGH ONTARIO ON
MONDAY.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...JLB
LONG TERM...VOSS
AVIATION...ROLFSON
MARINE...KF
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
354 AM EDT THU JUN 20 2013
.SHORT TERM...(THIS EVENING THROUGH THURSDAY)
ISSUED AT 429 PM EDT WED JUN 19 2013
WV IMAGERY AND RUC ANALYSIS INDICATED WNW MID/UPPER LEVEL FLOW
THROUGH THEN NRN GREAT LAKES BETWEEN A TROUGH OVER ERN CANADA AND A
RIDGE OVER THE PLAINS. SCT SHRA AND ISOLD TSRA HAD DEVELOPED NEAR
CYRL ON THE TAIL OF A SHORTWAVE TROUGH THROUGH NW ONTARIO. AN
UPSTREAM SHRTWV WAS ALSO LOCATED OVER ERN SD. AT THE SFC...SRLY
WINDS HAD INCREASED BETWEEN HIGH PRES OVER THE ERN GREAT LAKES AND A
TROUGH EXTENDING INTO ND FROM LOW PRES W OF JAMES BAY. LOW LEVEL
MOISTURE WAS ONLY SLOWLY INCREASING WITH DEWPOINTS CLIMBING TO NEAR
50F OVER THE WEST.
TONIGHT...EVEN THOUGH THE FORCING WITH THE NW ONTARIO SHRTWV WILL
REMAIN NORTH OF THE CWA...MODELS SUGGEST THAT THE SHRA AND POSSIBLY
SOME TSRA WILL DEVELOP LATER THIS EVENING NW OF LAKE SUPERIOR AND
SLIDE INTO THE WRN CWA OVERNIGHT. MOISTURE TRANSPORT AND THE
POSITION OF THE 850-700 MB FRONTAL ZONE FAVORS GREATER PCPN
CHANCES/COVERAGE OVER NW LAKE SUPERIOR INTO MAINLY THE NW CWA.
MUCAPE VALUES ARE EXPECTED TO BE HIGH ENOUGH FOR ELEVATED TSRA
DEVELOPMENT.
THURSDAY...THE COMBINATION OF INCREASING MOISTURE
TRANSPORT...DAYTIME HEATING AND THE SD SHRTWV SHOULD BRING
INCREASING SHRA/TSRA COVERAGE ACROSS THE CWA. ALTHOUGH INSTABILITY
WILL BE MARGINAL FOR STRONGER STORMS WITH MLCAPE VALUES INTO THE
500-1000 J/KG RANGE...AND A RELATIVELY NARROW CAPE PROFILE....SOME
STORMS WITH SMALL HAIL AND GUSTY WINDS TO 35 MPH MAY BE POSSIBLE.
.LONG TERM...(THURSDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 429 PM EDT WED JUN 19 2013
CONVECTION WILL MAKE FOR A VERY TRICKY AND UNCERTAIN FORECAST THU
NIGHT THROUGH AT LEAST THE WEEKEND.
AN UPPER RIDGE WILL MOVE E INTO THE AREA THU NIGHT THROUGH THE
MIDDLE OF NEXT WEEK. AT THE SFC...A WEAK LOW WILL REMAIN FAIRLY
STATIONARY OVER THE CENTRAL AND NRN PLAINS...LEAVING A WARM FRONT
ACROSS OR NEAR THE CWA THROUGH THIS WEEKEND. CONFIDENCE IS VERY LOW
/AS WITH MOST CONVECTIVE SITUATIONS/ WITH THE EXACT TRACK/TIMING OF
ANY CONVECTIVE COMPLEXES MOVING ALONG OR NEAR THE WARM FRONT. MODELS
SHOW MULTIPLE SCENARIOS FOR CONVECTIVE DEVELOPMENT AND
MOVEMENT...INCLUDING MOVING THE WARM FRONT N OF THE CWA KEEPING THE
BULK OF CONVECTION N OF THE CWA...TO HAVING THE WARM FRONT STALL S
OF THE CWA WHICH WOULD KEEP MOST OF THE CONVECTION S. OVERALL...THE
BULK OF THE MODELS SHOW CONVECTIVE COMPLEXES MOVING OVER THE
CWA...SO WILL CONTINUE TO PUT THAT INTO THE FORECAST AS HAS BEEN
DONE BY PREVIOUS SHIFTS.
SOME OF THE THUNDERSTORMS COULD VERY WELL BE STRONG WITH LARGE HAIL
AND DAMAGING WINDS THE PRIMARY THREATS...BUT CONFIDENCE IS STILL TOO
LOW TO INCORPORATE THAT INTO THE FORECAST BUT WILL CONTINUE SOME
MENTION OF STRONGER STORMS IN THE HWO. SPC HAS AREAS ALONG THE
BORDER UNDER A SLIGHT RIGHT...AND GENERALLY AGREE WITH THAT GIVEN
THE LOCATION OF THE GREATEST INSTABILITY. MODELS SHOW UP TO 4500J/KG
/GFS/ OF SBCAPE NOSING INTO WRN UPPER MI FRI AFTERNOON...BUT THAT IS
THE HIGHEST AMOUNT AND LOOKS LIKE LOW LEVELS ARE OVERLY MOIST IN THE
MODEL. THE NAM IS ANOTHER MODEL THAT SEEMS TOO HIGH ON LOW LEVEL
MOISTURE AND SBCAPE AT UP TO 3500J/KG ON FRI. ECMWF AND GEM SEEM
MORE REASONABLE AT 1000-1500J/KG ALONG THE WI BORDER SO WILL FAVOR
THAT SOLUTION. COULD HAVE DAYTIME CONVECTION BREAK OUT OVER WRN AND
CENTRAL UPPER MI...BUT MOST LIKELY SCENARIO AT THIS POINT CONTINUES
TO BE CONVECTION FORMING UPSTREAM AND MOVING TO THE ESE ALONG THE
FORWARD PROPAGATING CORFIDI VECTORS AND INSTABILITY GRADIENT FRI.
ANOTHER RISK FACTOR WILL BE HEAVY RAIN WITH ANY THUNDERSTORMS AS
PWATS WILL BE 150-200 PERCENT OF NORMAL.
SAT AND SUN LOOK SIMILAR TO FRI...WITH SIMILAR UNCERTAINTY DUE TO
CONVECTIVE UNCERTAINTY. IN FACT...SIMILAR CONDITIONS SHOULD BE
OBSERVED INTO THE MIDDLE OF NEXT WEEK...BUT CONFIDENCE INCREASES TOO
MUCH MON-WED TO TALK TOO MUCH ABOUT THIS TIME FRAME.
LOOKING AT TEMPS...SHOULD SEE SFC TEMPS INCREASE SLIGHTLY FROM DAY
TO DAY THROUGH THE FORECAST PEROID WITH HIGHS IN THE 80S ACROSS A
LARGE PART OF UPPER MI BY SUN.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z THURSDAY NIGHT)
ISSUED AT 1209 AM EDT THU JUN 20 2013
OVERNIGHT...ATTENTION TURNS TO SFC TROF DROPPING S TOWARD THE UPPER
LAKES IN ASSOCIATION WITH SHORTWAVE CURRENTLY PASSING THRU NRN
ONTARIO. SCT SHRA AND DIMINISHING TSRA HAVE BEEN OCCURRING
ALONG/AHEAD OF TROF...AND SOME OF THOSE SHRA WILL HOLD TOGETHER AND
AFFECT KCMX OVERNIGHT AND THEN POSSIBLY KIWD/KSAW THIS MORNING.
CONFIDENCE IN SHRA OCCURRING AT KIWD/KSAW IS LOWER THAN AT KCMX...SO
ONLY VCSH WAS UTILIZED AT THOSE 2 TERMINALS. DESPITE -SHRA...INITIAL
DRIER AIR AT THE LOW-LEVELS SHOULD RESULT IN VFR CONDITIONS INTO THE
MORNING. HOWEVER...WILL NEED TO WATCH KCMX AS ANY UPSLOPE WIND OFF
THE LAKE COULD RESULT IN LOWER CLOUDS/FOG POSSIBLY FORMING THIS
MORNING. THIS AFTN...DAYTIME HEATING SHOULD GENERATE SCT SHRA/TSRA
ACROSS UPPER MI WITH BETTER POTENTIAL AT KIWD/KSAW. THERE IS LIMITED
CONFIDENCE IN PCPN ACTUALLY OCCURRING AT A TERMINAL...SO ONLY VCTS
WAS INCLUDED IN FCST. IF SHRA/TSRA OCCUR AT KIWD/KSAW...MVFR
CONDITIONS WOULD LIKELY ACCOMPANY PCPN. SCT CONVECTION SHOULD END BY
EVENING. DURING THE EVENING...COMBINATION OF A COOL EASTERLY UPSLOPE
WIND OFF THE LAKE INTO HIGHER DWPT AIR OVER THE KEWEENAW MAY RESULT
IN FOG/STRATUS DEVELOPING AT KCMX.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 354 AM EDT THU JUN 20 2013
FOG...AND ANY STRONGER STORMS /WITH WINDS AND/OR SMALL HAIL/ WILL BE
THE MAIN THREATS THROUGH THE WEEKEND. OTHERWISE WINDS SHOULD REMAIN
AT OR BELOW 25KTS.
A TROUGH OF ACROSS LAKE SUPERIOR WILL...DEEPEN FRIDAY NIGHT...AND
AGAIN SUNDAY THROUGH MONDAY. THIS WILL BE IN RESPONSE TO AN
ELONGATED AREA OF LOW PRESSURE STRETCHING FROM SOUTHWESTERN CANADA
THROUGH EASTERN COLORADO. EXPECT THE AREA OF LOW PRESSURE TO
CONSOLIDATE ACROSS THE CENTRAL PLAINS ON SATURDAY...BEFORE SHIFTING
INTO MANITOBA ON SUNDAY...AND EXITING EASTWARD THROUGH ONTARIO ON
MONDAY.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...JLB
LONG TERM...TITUS
AVIATION...ROLFSON
MARINE...KF
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
1209 AM EDT THU JUN 20 2013
.SHORT TERM...(THIS EVENING THROUGH THURSDAY)
ISSUED AT 429 PM EDT WED JUN 19 2013
WV IMAGERY AND RUC ANALYSIS INDICATED WNW MID/UPPER LEVEL FLOW
THROUGH THEN NRN GREAT LAKES BETWEEN A TROUGH OVER ERN CANADA AND A
RIDGE OVER THE PLAINS. SCT SHRA AND ISOLD TSRA HAD DEVELOPED NEAR
CYRL ON THE TAIL OF A SHORTWAVE TROUGH THROUGH NW ONTARIO. AN
UPSTREAM SHRTWV WAS ALSO LOCATED OVER ERN SD. AT THE SFC...SRLY
WINDS HAD INCREASED BETWEEN HIGH PRES OVER THE ERN GREAT LAKES AND A
TROUGH EXTENDING INTO ND FROM LOW PRES W OF JAMES BAY. LOW LEVEL
MOISTURE WAS ONLY SLOWLY INCREASING WITH DEWPOINTS CLIMBING TO NEAR
50F OVER THE WEST.
TONIGHT...EVEN THOUGH THE FORCING WITH THE NW ONTARIO SHRTWV WILL
REMAIN NORTH OF THE CWA...MODELS SUGGEST THAT THE SHRA AND POSSIBLY
SOME TSRA WILL DEVELOP LATER THIS EVENING NW OF LAKE SUPERIOR AND
SLIDE INTO THE WRN CWA OVERNIGHT. MOISTURE TRANSPORT AND THE
POSITION OF THE 850-700 MB FRONTAL ZONE FAVORS GREATER PCPN
CHANCES/COVERAGE OVER NW LAKE SUPERIOR INTO MAINLY THE NW CWA.
MUCAPE VALUES ARE EXPECTED TO BE HIGH ENOUGH FOR ELEVATED TSRA
DEVELOPMENT.
THURSDAY...THE COMBINATION OF INCREASING MOISTURE
TRANSPORT...DAYTIME HEATING AND THE SD SHRTWV SHOULD BRING
INCREASING SHRA/TSRA COVERAGE ACROSS THE CWA. ALTHOUGH INSTABILITY
WILL BE MARGINAL FOR STRONGER STORMS WITH MLCAPE VALUES INTO THE
500-1000 J/KG RANGE...AND A RELATIVELY NARROW CAPE PROFILE....SOME
STORMS WITH SMALL HAIL AND GUSTY WINDS TO 35 MPH MAY BE POSSIBLE.
.LONG TERM...(THURSDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 429 PM EDT WED JUN 19 2013
CONVECTION WILL MAKE FOR A VERY TRICKY AND UNCERTAIN FORECAST THU
NIGHT THROUGH AT LEAST THE WEEKEND.
AN UPPER RIDGE WILL MOVE E INTO THE AREA THU NIGHT THROUGH THE
MIDDLE OF NEXT WEEK. AT THE SFC...A WEAK LOW WILL REMAIN FAIRLY
STATIONARY OVER THE CENTRAL AND NRN PLAINS...LEAVING A WARM FRONT
ACROSS OR NEAR THE CWA THROUGH THIS WEEKEND. CONFIDENCE IS VERY LOW
/AS WITH MOST CONVECTIVE SITUATIONS/ WITH THE EXACT TRACK/TIMING OF
ANY CONVECTIVE COMPLEXES MOVING ALONG OR NEAR THE WARM FRONT. MODELS
SHOW MULTIPLE SCENARIOS FOR CONVECTIVE DEVELOPMENT AND
MOVEMENT...INCLUDING MOVING THE WARM FRONT N OF THE CWA KEEPING THE
BULK OF CONVECTION N OF THE CWA...TO HAVING THE WARM FRONT STALL S
OF THE CWA WHICH WOULD KEEP MOST OF THE CONVECTION S. OVERALL...THE
BULK OF THE MODELS SHOW CONVECTIVE COMPLEXES MOVING OVER THE
CWA...SO WILL CONTINUE TO PUT THAT INTO THE FORECAST AS HAS BEEN
DONE BY PREVIOUS SHIFTS.
SOME OF THE THUNDERSTORMS COULD VERY WELL BE STRONG WITH LARGE HAIL
AND DAMAGING WINDS THE PRIMARY THREATS...BUT CONFIDENCE IS STILL TOO
LOW TO INCORPORATE THAT INTO THE FORECAST BUT WILL CONTINUE SOME
MENTION OF STRONGER STORMS IN THE HWO. SPC HAS AREAS ALONG THE
BORDER UNDER A SLIGHT RIGHT...AND GENERALLY AGREE WITH THAT GIVEN
THE LOCATION OF THE GREATEST INSTABILITY. MODELS SHOW UP TO 4500J/KG
/GFS/ OF SBCAPE NOSING INTO WRN UPPER MI FRI AFTERNOON...BUT THAT IS
THE HIGHEST AMOUNT AND LOOKS LIKE LOW LEVELS ARE OVERLY MOIST IN THE
MODEL. THE NAM IS ANOTHER MODEL THAT SEEMS TOO HIGH ON LOW LEVEL
MOISTURE AND SBCAPE AT UP TO 3500J/KG ON FRI. ECMWF AND GEM SEEM
MORE REASONABLE AT 1000-1500J/KG ALONG THE WI BORDER SO WILL FAVOR
THAT SOLUTION. COULD HAVE DAYTIME CONVECTION BREAK OUT OVER WRN AND
CENTRAL UPPER MI...BUT MOST LIKELY SCENARIO AT THIS POINT CONTINUES
TO BE CONVECTION FORMING UPSTREAM AND MOVING TO THE ESE ALONG THE
FORWARD PROPAGATING CORFIDI VECTORS AND INSTABILITY GRADIENT FRI.
ANOTHER RISK FACTOR WILL BE HEAVY RAIN WITH ANY THUNDERSTORMS AS
PWATS WILL BE 150-200 PERCENT OF NORMAL.
SAT AND SUN LOOK SIMILAR TO FRI...WITH SIMILAR UNCERTAINTY DUE TO
CONVECTIVE UNCERTAINTY. IN FACT...SIMILAR CONDITIONS SHOULD BE
OBSERVED INTO THE MIDDLE OF NEXT WEEK...BUT CONFIDENCE INCREASES TOO
MUCH MON-WED TO TALK TOO MUCH ABOUT THIS TIME FRAME.
LOOKING AT TEMPS...SHOULD SEE SFC TEMPS INCREASE SLIGHTLY FROM DAY
TO DAY THROUGH THE FORECAST PEROID WITH HIGHS IN THE 80S ACROSS A
LARGE PART OF UPPER MI BY SUN.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z THURSDAY NIGHT)
ISSUED AT 1209 AM EDT THU JUN 20 2013
OVERNIGHT...ATTENTION TURNS TO SFC TROF DROPPING S TOWARD THE UPPER
LAKES IN ASSOCIATION WITH SHORTWAVE CURRENTLY PASSING THRU NRN
ONTARIO. SCT SHRA AND DIMINISHING TSRA HAVE BEEN OCCURRING
ALONG/AHEAD OF TROF...AND SOME OF THOSE SHRA WILL HOLD TOGETHER AND
AFFECT KCMX OVERNIGHT AND THEN POSSIBLY KIWD/KSAW THIS MORNING.
CONFIDENCE IN SHRA OCCURRING AT KIWD/KSAW IS LOWER THAN AT KCMX...SO
ONLY VCSH WAS UTILIZED AT THOSE 2 TERMINALS. DESPITE -SHRA...INITIAL
DRIER AIR AT THE LOW-LEVELS SHOULD RESULT IN VFR CONDITIONS INTO THE
MORNING. HOWEVER...WILL NEED TO WATCH KCMX AS ANY UPSLOPE WIND OFF
THE LAKE COULD RESULT IN LOWER CLOUDS/FOG POSSIBLY FORMING THIS
MORNING. THIS AFTN...DAYTIME HEATING SHOULD GENERATE SCT SHRA/TSRA
ACROSS UPPER MI WITH BETTER POTENTIAL AT KIWD/KSAW. THERE IS LIMITED
CONFIDENCE IN PCPN ACTUALLY OCCURRING AT A TERMINAL...SO ONLY VCTS
WAS INCLUDED IN FCST. IF SHRA/TSRA OCCUR AT KIWD/KSAW...MVFR
CONDITIONS WOULD LIKELY ACCOMPANY PCPN. SCT CONVECTION SHOULD END BY
EVENING. DURING THE EVENING...COMBINATION OF A COOL EASTERLY UPSLOPE
WIND OFF THE LAKE INTO HIGHER DWPT AIR OVER THE KEWEENAW MAY RESULT
IN FOG/STRATUS DEVELOPING AT KCMX.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 429 PM EDT WED JUN 19 2013
WINDS SHOULD REMAIN BELOW 25KTS THROUGH THE PERIOD...WITH RELATIVELY
LOW WAVES. THE MAIN HAZARD WILL BE STRONGER WINDS/HAIL/LIGHTNING
WITH ANY THUNDERSTORMS MOVING ACROSS LAKE SUPERIOR FROM LATE TONIGHT
THROUGH INTO EARLY NEXT WEEK. AREAS OF FOG THAT DEVELOP AS A RESULT
OF INCREASED MOISTURE AND SHOWER ACTIVITY MAY ALSO BECOME LOCALLY DENSE.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...JLB
LONG TERM...TITUS
AVIATION...ROLFSON
MARINE...JLB
AREA FORECAST DISCUSSION
NWS TWIN CITIES/CHANHASSEN MN
638 PM CDT FRI JUN 21 2013
.SHORT TERM...(THIS EVENING THROUGH SATURDAY)
ISSUED AT 345 PM CDT FRI JUN 21 2013
ANOTHER ACTIVE SHORT TERM IS EXPECTED...WITH POTENTIAL FOR BOTH
ANOTHER SEVERE WEATHER EVENT AND A SIGNIFICANT FLASH FLOOD EVENT
OVER SRN MN BEING CLOSELY MONITORED TONIGHT.
WARM FRONTAL BOUNDARY AT 3PM STRETCHES FROM ROUGHLY MARSHALL OVER
TOWARD RED WING. VERY UNSTABLE AIRMASS COMBINED WITH A WAVE THAT
CAME OUT OF THE BLACK HILLS THIS MORNING HAS SEVER CLUSTER OF STORMS
OVER SODAK THAT IS RAPIDLY APPROACHING SW MN. THE SYSTEM IS STARTING
TO BOW...WITH HURON REPORTING A WIND GUST OF 87 MPH. HAVE BEEN
LEANING ON THE HRRR HEAVILY ALL DAY TO TRACK THIS SYSTEM ACROSS THE
AREA. EXPECT THESE STORMS TO BASICALLY FOLLOW THE WARM FRONT AND
850-300 THICKNESS LINES TO THE ESE ACROSS SRN MN. TORNADO/LARGE HAIL
TREAT WILL BE HIGHEST ALONG THE SODAK BORDER...WITH THE THREAT
TRANSITIONING OVER TO MORE OF A WIND THREAT AS YOU HEAD EAST. WOULD
NOT BE SURPRISED IF BY 5 OR 6 PM WE ARE COORDINATING WITH THE SPC
FOR A SVR THUNDERSTORM WATCH TO THE EAST OF THE CURRENT TOR WATCH.
FOR TONIGHT THOUGH...THE REAL BIG CONCERN IS THE POTENTIAL FOR A
SIGNIFICANT RAINFALL/FLASH FLOODING EVENT ACROSS SRN MN. THE RAP HAS
THE NOSE OF A PERSISTENT 40-50 KT LLJ COMING UP OUT OF THE PLAINS
AND REMAINING MORE OR LESS STATIONARY INTO SW MN. AS THE HRRR
SHOWS...WITH 3000-5000 J/KG OF MUCAPE REMAINING IN PLACE WITH THE
LLJ...THE PROBABILITY FOR ADDITIONAL TSRA DEVELOPMENT BACK INTO THE
SD/NEB/IA AREA THROUGH THE NIGHT WILL BE HIGH. THIS WILL LEAD TO A
THREAT FOR TRAINING OF STORMS TONIGHT...WITH THE POTENTIAL FOR SOME
RATHER SIGNIFICANT RAINFALL TOTALS IN EXCESS OF 6 INCHES POSSIBLE
FOR TONIGHT. GIVEN THE POTENTIAL...HAVE ISSUED A FLASH FLOOD WATCH
FOR AREAS ALONG AND SOUTH OF AN APPLETON TO CHIPPEWA FALLS
LINE...WITH THE POTENTIAL FOR SEEING MULTIPLE ROUNDS OF STORMS IS
HIGHEST. GIVEN THE SOUTHERN POSITION OF THE WARM FRONT...LESSER
AMOUNTS OF RAINFALL ARE CURRENTLY ANTICIPATED OVER CENTRAL MINNESOTA
INTO NW WISCONSIN.
LIKE TODAY...EXPECT ACTIVITY TO WIND DOWN THROUGH THE MORNING ACROSS
THE MPX AREA...WITH MUCH OF THE LATE MORNING INTO THE EARLY
AFTERNOON REMAINING DRY. THE BIG DIFFERENCE THOUGH ON SATURDAY TO
THE PAST TWO DAYS...IS THE SYNOPTIC COLD/STATIONARY FRONT AND LOW
PRESSURE SYSTEM WILL BE FARTHER EAST. BY THE AFTERNOON...MODELS SHOW
A LEE SIDE LOW DEVELOPING OVER ERN COLORADO...WITH A STATIONARY
FRONT/PRESSURE TROUGH EXTENDING TO THE NORTHEAST TOWARD WRN MN. WITH
THE SYNOPTIC FEATURES FARTHER EAST TOMORROW...THIS SHOULD INCREASE
THE CHANCES FOR THUNDERSTORMS DEVELOPING IN THE AFTERNOON ACROSS THE
MPX AREA...WHICH WILL LEAD TO A HIGHER PROBABILITY FOR SEEING
TORNADOES OR HAIL DURING THE AFTERNOON...BEFORE ANOTHER POTENTIAL
ROUND OF STORMS GOING INTO SATURDAY NIGHT.
.LONG TERM...(SATURDAY NIGHT THROUGH FRIDAY)
ISSUED AT 345 PM CDT FRI JUN 21 2013
NO SIGNIFICANT CHANGES FROM THE PREVIOUS FORECAST...WITH SEVERE AND
HYDRO CONCERNS CONTINUING THROUGH EARLY NEXT WEEK. THE UPPER LEVEL
LOW WILL LINGER JUST TO THE WEST...WITH THE SURFACE TROUGH INCHING
EVER CLOSER TO WESTERN MINNESOTA BY THE WEEKEND...AND THE FRONTAL
BOUNDARY STALLED OUT EAST/WEST ACROSS THE FORECAST AREA ONLY TO
OSCILLATE NORTH/SOUTH WITH EACH CONVECTIVE OUTFLOW BOUNDARY. THE
TROPICAL AIRMASS WILL REMAIN IN PLACE THROUGH EARLY NEXT WEEK...WITH
PWAT VALUES IN THE 1.75 TO 2.00 INCH RANGE. SREF 21.09 MLCAPE PLUMES
CONTINUE TO SHOW 2500 TO 4000J/KG DURING THE AFTERNOON...AND THIS
SEEMS REASONABLE CONSIDERING WHAT IS CURRENTLY GOING ON ACROSS
SOUTHWEST MINNESOTA. DEEP LAYER SHEAR WILL ONLY BE IN THE 25KT
RANGE...BUT THE SEVERE WEATHER REMAINS A CONCERN SINCE THE STORMS
MAY BE ABLE TO MODIFY THEIR OWN ENVIRONMENT AS IS THE CASE THIS
AFTERNOON ACROSS EASTERN SOUTH DAKOTA. AS THE SURFACE TROUGH SLOWLY
PROGRESSES EASTWARD...THE POTENTIAL FOR AFTERNOON CONVECTION WILL
INCREASE AS WELL. THEREFORE THE MISSISSIPPI RIVER VALLEY MAY
TRANSITION FROM A PURELY NOCTURNAL EVENT AS WAS THE CASE LAST
NIGHT...TO MORE OF A AFTERNOON AND EVENING FOCUS. FORECAST MODELS
CONTINUE TO SHOW A SHORTWAVE MOVING ACROSS NORTHERN MINNESOTA
SATURDAY NIGHT...SO IF STORMS DO NOT DEVELOP TOMORROW AFTERNOON THEY
WILL CERTAINLY FORM AHEAD OF THAT WAVE. ANOTHER WAVE FOLLOWS FOR
SUNDAY EVENING...SO COULD SEE SOME QUICK REDEVELOPMENT DURING THE
DAY ON SUNDAY.
LOOKING AHEAD...BOTH THE GFS AND ECMWF TRANSITION TO A MORE ZONAL
PATTERN WITH THE H250 JET STRADDLING THE INTERNATIONAL BORDER...AND
CONTINUED CHANCES FOR POPS THROUGH THE MIDDLE OF THE WEEK. THE UPPER
LEVEL RIDGE TRIES TO BUILD ACROSS THE ROCKIES BY LATE NEXT
WEEK...BUT CONFIDENCE IS LOW IN THE DEVELOPMENT OF THIS FEATURE
GIVEN THE CONTINUED DELAYED ONSET WITH EACH MODEL RUN.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z SATURDAY EVENING)
ISSUED AT 613 PM CDT FRI JUN 21 2013
CONVECTIVE COMPLEX WILL BE MOVING ACROSS EASTERN MN THROUGH 03Z.
WNW WINDS GUSTING 45 KNOTS LIKELY ESPECIALLY FROM THE TWIN CITIES
METRO ON NORTHWARD. OTHER STORMS DEVELOPING ACROSS SOUTH CENTRAL
MN IN AREA OF INCREASING LOW LEVEL MOISTURE TRANSPORT. THESE WILL
PROGRESS INTO WEST CENTRAL WI DURING THE EVENING BUT CONFIDENCE IS
NOT HIGH ON HOW STRONG THESE STORMS WILL BE. CEILINGS/VSBYS
DROPPING TO IFR OR LOWER IN THE STORMS. MORE STORMS ARE POSSIBLE
OVERNIGHT BUT CONFIDENCE IS NOT HIGH WITH THERE FORMATION IN
CENTRAL SD. WILL INDICATE MINOR SHRA/TSRA PASSING THROUGH. SIMILAR
SCENARIO TONIGHT AS TO LAST NIGHT WITH MVFR CEILINGS DEVELOPING
IN THE WAKE OF THE STORMS OVERNIGHT AND PERSISTING THROUGH SATURDAY
MORNING. THERE WILL ALSO BE STRONG N TO NE WINDS DEVELOPING BEHIND
THE STORMS THIS EVENING WITH GUSTS INTO THE 30 KNOT RANGE LIKELY.
KMSP...POTENTIAL FOR STRONG WEST WINDS (G45 KTS) PASSING THROUGH
THE AIRFIELD BETWEEN 01Z-02Z FOR ABOUT AN HOUR. WINDS BECOME MORE
NORTHERLY IN THE WAKE OF THE EARLY EVENING THUNDERSTORMS. MVFR
CEILINGS LIKELY AGAIN DURING THE LATE NIGHT THROUGH SATURDAY
MORNING WITH A VERY MOIST AIRMASS IN PLACE. CONFIDENCE NOT HIGH ON
THE TIMING ON FURTHER SHRA/TSTM ACTIVITY LATE TONIGHT.
/OUTLOOK FOR KMSP/
SUN...TSRA LIKELY. VFR OUTSIDE OF TSRA. WINDS SSW 10-15 KTS.
MON...CHC TSRA. VFR OUTSIDE OF TSRA. WINDS S 5-10 KTS.
TUE...CHC TSRA. VFR OUTSIDE OF TSRA. WINDS SSE 10-15 KTS.
&&
.HYDROLOGY...
ISSUED AT 345 PM CDT FRI JUN 21 2013
AS ALLUDED TO EARLIER PWATS WILL BE IN THE 90TH PERCENTILE
THOUGH EARLY NEXT WEEK. THE AREA IS INCREASINGLY VULNERABLE TO BOTH
FLASH FLOODING...AND RIVER FLOODING GIVEN THE WIDESPREAD RAINFALL
AMOUNTS OF 2-4 INCHES FALLING LAST NIGHT. THE EAST/WEST FRONTAL
BOUNDARY SUPPORTS TRAINING THUNDERSTORMS...AND THE H925 MOISTURE
TRANSPORT SURGES NORTHWARD OVERNIGHT AS THE LOW LEVEL JET DECOUPLES
FROM THE BOUNDARY LAYER. CONTINGENCY FORECAST BASED OFF DIFFERENT
QPF SCENARIOS SHOW THE POTENTIAL FOR SIGIFICANT FLOODING BY EARLY
NEXT WEEK ALONG THE QUICKER RESPONSE RIVERS...AND EVENTUALLY THE
LARGER MAIN STEMS OF THE MINNESOTA AND MISSISSIPPI RIVER.
&&
.MPX WATCHES/WARNINGS/ADVISORIES...
MN...FLASH FLOOD WATCH THROUGH SATURDAY AFTERNOON FOR MNZ041>045-
047>070-073>078-082>085-091>093.
WI...FLASH FLOOD WATCH THROUGH SATURDAY AFTERNOON FOR WIZ014>016-
023>028.
&&
$$
SHORT TERM...MPG
LONG TERM...JRB
AVIATION...RAH
HYDROLOGY...JRB
AREA FORECAST DISCUSSION
NWS TWIN CITIES/CHANHASSEN MN
422 PM CDT THU JUN 20 2013
.SHORT TERM...(THIS EVENING THROUGH FRIDAY)
ISSUED AT 419 PM CDT THU JUN 20 2013
MAIN CONCERN FOR THE SHORT TERM IS WHAT IS LOOKING MORE AND MORE
LIKELY TO BE A STRONG TO SEVERE MCS THAT WILL BE MOVING ACROSS THE
MPX AREA TONIGHT.
BEHIND THE MORNING CONVECTION...A DECENT WARM FRONT HAS DEVELOPED
ACROSS CENTRAL MN...STRETCHING FROM FERGUS FALLS OVER TOWARD MILLE
LACS. ANOTHER MORE N/S ORIENTED WARM FRONT/OUTFLOW FEATURE IS ALSO
BEARING ITSELF OUT NICELY ON KMPX AND TMSP ACROSS THE TWIN CITIES
METRO AREA. HAVE SEEN SOME DECENT MIXING OUT OF DEWPS SOUTHWEST OF
THESE BOUNDARIES...WHICH HAS ALLOWED TEMPS ACROSS SRN/WRN MN TO WARM
INTO THE UPPER 80S...WITH EVEN A FEW 90S MAKING AN APPEARANCE.
THE MAIN THING WE HAVE BEEN WATCHING THIS AFTERNOON IS WHETHER OR
NOT CONVECTION WOULD FIRE ALONG THESE WARM FRONT/OUTFLOW BOUNDARIES.
SPECIAL 18Z KMPX SOUNDING SHOWED A FAIR AMOUNT OF DRY AIR IN PLACE
TODAY...AND IT APPEARS THAT ENTRAINMENT OF DRY AIR HAS HELPED KEEP
STORMS FROM DEVELOPING OVER HERE. INSTEAD...EXPECT MORE ROBUST
STORMS TO INITIATE AROUND ABR THIS EVENING /IN REGION OF SVR WATCH
331/. IT IS THE STORMS THAT INITIATE IN THIS REGION THAT LOOK TO
CONGEAL INTO A SYSTEM THAT THEN COMES ROLLING ACROSS THE MPX AREA
TONIGHT.
AS FOR TONIGHT...AGREEMENT IN REFLECTIVITY FORECASTS AMONGST MODELS
IS REALLY QUITE REMARKABLE...LEADING TO THE HIGH CONFIDENCE IN A
STRONG TO SEVERE QLCS WITH BOWING SEGMENTS WORKING ACROSS THE MPX
AREA TONIGHT. ABOUT THE ONLY DIFFERENCE BETWEEN THE MODELS IS ONE OF
TIMING...BUT EVEN THERE...THE DIFFERENCES ON THE ORDER OF A COUPLE
OF HOURS. USING THE 15Z SREF TO GET A SENSE OF THE BACKGROUND
ENVIRONMENT FOR THIS SYSTEM...IT IS SHOWING THE PROBABILITY OF
MUCAPE EXCEEDING 2000 J/KG BEING NEARLY 100%...WHILE THE
PROBABILITY OF THE 0-1KM HELICITY EXCEEDING 100 M**2/S**2 IS UP
AROUND 70 PERCENT. ADD INTO THAT...THERE WILL BE A SRLY LLJ
INCREASING TO AROUND 40 KTS. WILL HAVE PLENTY OF INSTABILITY THROUGH
THE NIGHT TO SUPPORT DEEP CONVECTION AND THE LOW LEVEL SHEAR
SHOULD BE SUFFICIENT TO KEEP THE COLD POOLS FROM OUTRUNNING THE
CONVECTION...SO A LONG-LIVED QLCS IS EXPECTED. BIGGEST CONCERN WILL
BE WINDS...WITH THE POTENTIAL FOR SOME GUSTS IN EXCESS OF 70
MPH...ESPECIALLY OUT IN WRN MN. IN ADDITION...GIVEN THE 0-1KM SHEAR
EXPECTED OUT AHEAD OF A SYSTEM WITH BOWING SEGMENTS...CAN NOT RULE
OUT THE QUICK SPIN UP ON THE LEADING EDGE OF THE LINE AS WELL. GIVEN
ALL OF THE ABOVE...DID ADD A MENTION OF SVR TO THE GRIDS WITH
DAMAGING WINDS.
BESIDE THE SEVERE THREAT...PWAT AHEAD OF THE SYSTEM WILL BE
INCREASING TO AROUND 1.5 INCHES...SO THIS SYSTEM SHOULD ALSO PRODUCE
SOME HEAVY RAINS. FOR NOW...THIS LOOKS TO BE A PROGRESSIVE
SYSTEM...SO DID NOT ISSUE A FLASH FLOOD WATCH. EVEN SO CURRENT QPF
GRIDS HAVE VALUES APPROACHING 2 INCHES IN THE WEST TONIGHT...SO THE
HYDRO ASPECT OF THINGS WILL NEED TO BE WATCHED AS WELL.
FOR FRIDAY...THE BIG QUESTION IS HOW DO OUTFLOWS MODULATE THE SFC
PATTERN AND WARM FRONT POSITION. TONIGHT/S MCS LOOKS TO CLEAR WRN WI
FRIDAY MORNING...AND AFTER THAT...MAY BE A PROLONGED BREAK IN
CONVECTION AS ATMOSPHERE RECHARGES DURING THE DAY. CURRENT THINKING
BASED ON THE GFS/ECMWF/GEM ALONG WITH THE NMM/ARW IS THAT STORMS
FRIDAY AFTERNOON...MUCH LIKE TODAY WILL INITIATE OVER THE
DAKOTAS...THEN TRACK EAST TOWARD MN FRIDAY NIGHT. WITH THAT
SAID...MOST MODELS SHOW A WARM FRONT SETTING UP ACROSS SRN MN INTO
WRN WI. BY 00Z SAT...THE LLJ WILL BEGIN TO REORGANIZE ITSELF TO THE
SOUTH...WITH THE NOSE IF IT MOVING UP INTO MN. SO ALTHOUGH MOST
GUIDANCE KEEP THE AREA DRY THROUGH FRIDAY AFTERNOON...THE PRESENCE
OF THE WARM FRONT ALONG WITH THE INCREASING LLJ RESULTED IN THE
CONTINUATION OF CHANCE POPS THROUGH THE AFTERNOON ON FRIDAY.
.LONG TERM...(FRIDAY NIGHT THROUGH THURSDAY)
ISSUED AT 419 PM CDT THU JUN 20 2013
AT THE START OF THE PERIOD FRIDAY NIGHT THE BROAD UPPER LEVEL WAVE
WILL BE LOCATED OVER THE HIGH PLAINS OF IDAHO AND MONTANA...WITH
SOUTHWEST FLOW ACROSS THE UPPER MIDWEST. THE SURFACE TROUGH WILL BE
ORIENTED FROM EASTERN COLORADO THROUGH THE MN/DAKOTA BORDER...WITH
SOUTHERLY WINDS BRINGING UP MOISTURE FROM THE GULF OD MEXICO. THIS
STAGNANT WEATHER PATTERN WILL LEAD TO SIGNIFICANT RAINFALL TOTALS
COME EARLY NEXT WEEK...WITH ADDITIONAL DETAILS FOUND IN THE HYDRO
SECTION OF THE AFD. IN ADDITION TO FLOODING RAINS...SEVERE WEATHER
WILL ALSO BE A THREAT.
AS ALLUDED TO IN YESTERDAYS AFD...INSTABILITY WILL NOT BE A PROBLEM
IN THE WARM SECTOR OF THE SURFACE LOW. PLUMES FROM THE SREF 20.09
DEVELOP AFTERNOON MLCAPE VALUES OF 3000-4000J/KG...WITH EFFECTIVE
SHEAR IN THE 25-35KT RANGE. ALSO...FORECAST SOUNDINGS FROM THE GFS
SHOW CONSISTENTLY SHOW 3000-4000 J/KG OF SBCAPE SOUTH OF THE WARM
FRONT THAT IS EXPECTED TO BE LAID OUT EAST/WEST ACROSS CENTRAL
MINNESOTA AND NORTHERN WISCONSIN. CONVERGENCE ALONG THIS FRONT WILL
BE THE FOCUS FOR AFTERNOON THUNDERSTORM DEVELOPMENT...AND THE VEERED
LOW LEVEL WIND PROFILES DIRECTLY ALONG THE BOUNDARY COULD SUPPORT AN
ISOLATED TORNADO. HOWEVER...THE MAIN THREAT WILL BE LARGE HAIL
DURING THE AFTERNOON...AND STRONG WINDS DURING THE EVENING/OVERNIGHT
HOURS AS THE STORMS GROW UPSCALE INTO A MCS.
BY EARLY NEXT WEEK A LONGWAVE TROUGH CURRENTLY IN THE GULF OF ALASKA
WILL TAKE THE PLACE OF THE AFOREMENTIONED SYSTEM...WHICH MEANS
LITTLE CHANGE IN THE ATMOSPHERIC CONDITIONS ACROSS THE MIDWEST. THE
SUBTROPICAL AIRMASS WILL REMAIN ACROSS THE REGION...WITH HIGH PWAT
VALUES AND WEAK STORM LAYER FLOW. IN SUMMATION...THE ACTIVE WEATHER
WILL CONTINUE INTO EARLY NEXT WEEK WITH INCREASING HYDRO CONCERNS IF
THE EXPECTED QPF VERIFIES.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z FRIDAY AFTERNOON)
ISSUED AT 110 PM CDT THU JUN 20 2013
CONFIDENCE INCREASING IN A LINE OF CONVECTION MOVING ACROSS THE
MPX TERMINALS THIS EVENING...BUT PLENTY OF QUESTIONS STILL IN
PLACE BEFORE THEN. AT 18Z...STORMS FROM THIS MORNING HAVE LEFT A
STRENGTHENING WARM FRONT FROM NEAR AXN OVER TO MORA. THE HRRR HAS
BEEN AGGRESSIVE WITH DEVELOPING STORMS THIS AFTERNOON NORTH OF THE
BOUNDARY...BUT THERE HAS NOT BEEN AS MUCH AGREEMENT WITH OTHER HI-
RES MODELS. IF SOMETHING WERE TO GO...THEN STC/MSP/RNH/EAU COULD
SEE A ROUND OF STORMS BETWEEN 22Z AND 04Z BEFORE THE MAIN LINE OF
CONVECTION ARRIVES TONIGHT. AS FOR THAT CONVECTION
TONIGHT...AGREEMENT ON A SQUALL LINE MOVING ACROSS THE AREA WITH
HI-RES MODELS IS STRIKING. USED A BLEND OF THESE MODELS TO TRY AND
TIME TEMPO TSRA GROUPS THROUGH TAFS TONIGHT. BEHIND THIS AREA OF
TSRA...NOT BELIEVING THE GFS-LAMP WITH ITS WIDESPREAD IFR CIGS OR
LOWER...THOUGH SOME MVFR VIS IN BR/HZ IS MORE PLAUSIBLE FOR LATE
TONIGHT. BEHIND THE SQUALL...SHOULD SEE A BREAK IN CONVECTION
THROUGH 18Z...BEFORE MORE STORMS DEVELOP AFTER 18Z FRIDAY...LIKELY
OVER ERN SODAK/WRN MN.
KMSP...CONFIDENCE QUITE HIGH ON A STRONG TO SEVERE SQUALL LINE
IMPACTING THE FIELD TONIGHT. THERE ARE TIMING DIFFERENCES BETWEEN
HI-RES MODELS...BUT THEY ARE MINOR...WITH STORM PEGGED TO MOVE IN
TO MSP BETWEEN 5Z AND 8Z DEPENDING ON WHICH SOLUTION YOU LOOK AT.
FOR THIS AFTERNOON...ADDED A VCSH MENTION AT 23Z...AS IF SOMETHING
WERE TO DEVELOP OVER CENTRAL MN NORTH OF THE WARM FRONT THIS
AFTERNOON...THEN MSP WOULD GET A PRECURSOR ROUND OF STORMS BEFORE
THE MAIN SHOW ARRIVES TONIGHT. OUTSIDE OF TSRA...EXPECT MAINLY VFR
CONDS. FOR WINDS...THEY LOOK TO BE FAIRLY STEADY BETWEEN 180 AND
150...THOUGH WILL VARY CONSIDERABLY WITH ANY CONVECTION THAT MOVES
THROUGH.
/OUTLOOK FOR KMSP/
SAT...TSRA LIKELY. VFR OUTSIDE OF TSRA. WINDS SE 10KTS
SUN...TSRA LIKELY. VFR OUTSIDE OF TSRA. WINDS SSW 10-15 KTS.
MON...CHC TSRA. VFR OUTSIDE OF TSRA. WINDS S 5-10KTS.
&&
.HYDROLOGY...
ISSUED AT 419 PM CDT THU JUN 20 2013
HYDROLOGY...SEVERAL ROUNDS OF SHOWERS AND THUNDERSTORMS EXPECTED
THIS WEEKEND ARE LIKELY TO PRODUCE HIGH RAINFALL TOTALS ACROSS THE
AREA...AND POTENTIALLY LEAD TO LOCALIZED FLOODING PROBLEMS. THE
PRIMARY TIME OF CONCERN WILL BE OVERNIGHT TONIGHT...AND AGAIN
OVERNIGHT FRIDAY NIGHT. THE OVERALL SYNOPTIC PATTERN IS SUCH THAT
A STRONG LOW PRESSURE AREA ACROSS THE WESTERN CONUS...AND A HIGH
PRESSURE AREA ACROSS THE EASTERN CONUS...ARE EXPECTED TO MOVE VERY
LITTLE OVER THE NEXT FEW DAYS...WHICH MEANS WE WILL REMAIN IN A
FAVORABLE ENVIRONMENT FOR THUNDERSTORMS DEVELOPMENT EACH
AFTERNOON/NIGHT. THIS SETUP HAS ALREADY BEGUN TO OPEN THE DOOR FOR
GULF MOISTURE TO BEGIN STREAMING INTO THE UPPER MIDWEST. SURFACE
DEW POINT TEMPERATURES WILL CONTINUE TO RISE TO AROUND 70...AND
PRECIPITABLE WATER VALUES RISE TO BETWEEN 1.5 AND 2 INCHES BY
TOMORROW MORNING. IN ADDITION...STRONG MOISTURE TRANSPORT FROM THE
GULF WILL PEAK DURING THE OVERNIGHT HOURS TONIGHT...AND AGAIN
TOMORROW NIGHT...WHICH WILL AID IN DEVELOPING HEAVY RAINFALL
RATES. THIS MOIST AIRMASS WILL REMAIN OVER THE AREA FOR THE NEXT
SEVERAL DAYS...AND GIVEN THE ABUNDANT MOISTURE
AVAILABLE...EXTREMELY HEAVY RAINFALL RATES OF UP TO 3 INCHES PER
HOUR WILL BE POSSIBLE IN STRONG THUNDERSTORMS THAT TRAVERSE THE
AREA THROUGH THE WEEKEND. ANTECEDENT SOIL CONDITIONS ARE GENERALLY
MOIST GIVEN THE WET SPRING...WHICH ENHANCES THE POTENTIAL FOR
FLASH FLOODING. THROUGH NEXT WEEK...RAINFALL TOTALS COULD RANGE
FROM 3 TO 5 INCHES...WHICH WILL ALSO LEAD TO RISES ON MAIN STEM
RIVERS NEXT WEEK.
&&
.MPX WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...NONE.
&&
$$
SHORT TERM...MPG
LONG TERM...JRB
AVIATION...MPG
HYDROLOGY...SPD
AREA FORECAST DISCUSSION
NWS TWIN CITIES/CHANHASSEN MN
110 PM CDT THU JUN 20 2013
.UPDATE...
18Z AVIATION DISCUSSION ADDED BELOW.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 345 AM CDT THU JUN 20 2013
SCATTERED HIGH BASED SHOWERS AND THUNDERSTORMS CONTINUE TO PLOW
NNE OVER CENTRAL MN AT THIS HOUR. ACTIVITY SUPPORTED BY WARM
FRONTAL BOUNDARY EMANATING FROM DISTANT SURFACE CYCLONE PARKED
OVER NE MONTANA AND SOUTHERN SASKATCHEWAN. SEVERAL SPS PRODUCTS
HAVE BEEN ISSUED DURING THE OVERNIGHT FOR PULSE T-STORMS
ASSOCIATED WITH THIS ACTIVITY. ALTHOUGH NO REPORTS ACCUMULATED...
A FEW OF THESE COULD EASILY HAVE PRODUCED DIME TO MAYBE EVEN
NICKEL SIZED HAIL. HOPWRF DEFINITELY HANDLING THIS ACTIVITY
BETTER THAN ANY OTHER SHORT TERM PROGNOSTICATOR...SO WILL CONTINUE
TO CALL UPON ITS SERVICES FOR SHORT TERM PAINTING OF FORECAST INTO
THIS AFTN. CONVERGENCE AT 250MB WILL SWEEP INTO SW CWA EARLY THIS
MORNING AND OVERSPREAD MUCH OF SOUTHERN MN BY 18Z. MOST OF PRESENT
SHOWER ACTIVITY WILL EXIT NORTHERN MN CWA BY ABOUT 14Z TIME FRAME.
SLGT TO CHANCE POPS WILL REMAIN IN FORCE OVER MUCH OF FA INTO THIS
AFTN...AS ABUNDANT HEATING FURTHER DESTABILIZES ATMOSPHERE WITH
LAPSE RATES IN THE 6 TO 7C RANGE ACROSS THE AREA. LOOKS LIKE BEST
CHANCE FOR SEVERE WEATHER ERUPTS OVER MOST OF THE CWA BETWEEN
21/03Z-21/09Z...AS STRONG THETA E ADVECTION TAGS UP WITH INTENSE
DIVERGENCE ALOFT PER GFS40 250MB LEVEL...AND 25 TO 30KT 850MB LOW
LEVEL JET. BEST CAPE VALUES IN THE 2000-2800 JOULE VARIANCE...WILL
BE ENCOUNTERED OVER SW MN...WITH 1500 TO NEAR 2000 NOTED OVER
REMAINDER OF SOUTHERN MN. LOOKS LIKE MAIN THREAT FOR SEVERE
WEATHER REMAINS WIND AND HAIL. HEAVY RAIN ALSO STILL A
POSSIBILITY...AS MOISTURE TRANSPORT VECTORS VERY STRONG OVER MUCH
OF THE FA OVERNIGHT. INCREASED TEMPS THIS AFTERNOON DUE TO RISING
850MB TEMPS INCREASING SOUTHERLY FLOW AND PLENTY OF DIFFUSE
SUNSHINE EVEN WITH POSSIBLE CIRRUS SHIELD.
.LONG TERM...(FRIDAY THROUGH WEDNESDAY)
ISSUED AT 345 AM CDT THU JUN 20 2013
FRI MRNG LOOKS TO START OUT WITH AN ONGOING MCS IN AN EXITING
AND/OR DECAYING MODE SHIFTING THRU ERN MN INTO WRN/NRN WI. THIS
IS IN RESPONSE TO THE BROAD-SCALE UPR RIDGE HAVING SHIFTED INTO THE
GREAT LAKES WITH A SFC LOW PRES CENTER EJECTING EWD OVER NRN MN.
WHILE HAVING THE MCS WOULD SEEMINGLY WORK OVER THE AREA...
INSTABILITY WILL BE REINVIGORATED AS A QUASI-STNRY RIDGE OVER THE
PLAINS BRINGS DEEP GULF MOISTURE INTO THE REGION AND A BROAD-SCALE
TROUGH OVER THE WRN STATES SHOVES SEVERAL SHORTWAVE DISTURBANCES
INTO THE N-CENTRAL CONUS. AS THE ATMOS GAINS ENERGY WITH THE
HEIGHTENED INSTABILITY...PERSISTENT STRONG MID- AND UPR-LEVEL
JETTING ALONG WITH STEEP LAPSE RATES WILL PROMOTE THE DEVELOPMENT
OF STRONG/SEVERE TSTMS BY LATE FRI AFTN INTO THE EVE...POSSIBLY
AGAIN IN THE FORM OF AT LEAST ONE EAST-WEST MCS ALONG A RESIDUAL
WMFNT. THIS ACTIVITY WILL QUICKLY SHIFT OFF TO THE E BY SAT
MRNG...BUT ITS INGREDIENTS WILL REMAIN IN PLACE WHICH WILL SET THE
STAGE FOR ANOTHER ROUND OF SIMILAR STORMS LATE SAT AFTN INTO SAT
EVE. CONTINUED LOW LEVEL WARM/MOIST AIR...WITH DEWPOINTS NEAR 70
THRU THE WEEKEND...ALONG WITH AN APCHG CDFNT AND ENHANCED LOW-
LEVEL JETTING WITHIN PRONOUNCED SWLY FLOW...AGAIN LOOK TO PROMOTE
THE FORMATION OF CLUSTERS OF LATE DAY TSTMS AND/OR AT LEAST MCS
SAT EVENING/NIGHT. HAZARDS REMAIN THE SAME FOR BOTH FRI NIGHT AND
SAT NIGHT EVENTS - MAINLY LARGE HAIL AND DMGG WIND BUT THE
ENHANCED JETTING AND VEERING WITH HEIGHT MAKES ISOLD TORNADOES
ANOTHER HIGHLIGHT. THERE IS MORE UNCERTAINTY WITH SAT EVE EVENTS
SINCE THEY WILL BE HIGHLY DEPENDENT ON WHAT HAPPENS FRI NIGHT...
BUT THERE IS STILL ENOUGH CHC FOR SPC TO PUT THE ENTIRE AREA IN
SLGT RISK FOR DAY 2 /FRI/ WITH ALL OF MN AND MOST OF THE WFO MPX
WI COUNTIES IN SLGT RISK FOR DAY 3 /SAT/.
THE CDFNT SLOWLY PROGRESSES E OVER THE REGION ON SUN...WORKING
WITHIN A CONTINUED DEEP MOISTURE PROFILE. DAILY PWAT VALUES FRI
THRU SUN ARE AT LEAST 1.75 INCHES. BROAD-SCALE LIFT WITH THE FNT
AND THE LIFTING OUT OF THE NW UPR TROUGH WILL TRANSITION THE
HAZARD FROM SEVERE WX TO ONE OF HEAVY RAIN/FLOODING. PRECIP TOTALS
THRU THE WEEKEND MAY EASILY ECLIPSE 3 INCHES...WITH SOME AREAS
POSSIBLY AS HIGH AS 5 INCHES...INCLUDING RATES IN THE 1-2 IN/HR
RANGE. PRECIP CHCS WIND DOWN LATE SUN INTO MON AS MORE ZONAL FLOW
GIVES WAY TO A SLIGHT RIDGE WITHIN THE FLOW FOR TUE. THIS FEATURE
IS ALSO SHORT-LIVED AS ANOTHER LONGWAVE TROUGH MOVES IN FROM THE
W...KEEPING THE WET PATTERN IN PLACE WITH SCATTERED SHWRS/TSTMS.
IN ADDITION...THE PRIMARILY ZONAL FLOW WILL NOT ALLOW FOR MUCH
ALTERATION IN TEMPERATURES ALL THRU EARLY NEXT WEEK. HIGHS WILL
CONTINUE IN THE 80S WITH LOWS ARND 70.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z FRIDAY AFTERNOON)
ISSUED AT 110 PM CDT THU JUN 20 2013
CONFIDENCE INCREASING IN A LINE OF CONVECTION MOVING ACROSS THE
MPX TERMINALS THIS EVENING...BUT PLENTY OF QUESTIONS STILL IN
PLACE BEFORE THEN. AT 18Z...STORMS FROM THIS MORNING HAVE LEFT A
STRENGTHENING WARM FRONT FROM NEAR AXN OVER TO MORA. THE HRRR HAS
BEEN AGGRESSIVE WITH DEVELOPING STORMS THIS AFTERNOON NORTH OF THE
BOUNDARY...BUT THERE HAS NOT BEEN AS MUCH AGREEMENT WITH OTHER HI-
RES MODELS. IF SOMETHING WERE TO GO...THEN STC/MSP/RNH/EAU COULD
SEE A ROUND OF STORMS BETWEEN 22Z AND 04Z BEFORE THE MAIN LINE OF
CONVECTION ARRIVES TONIGHT. AS FOR THAT CONVECTION
TONIGHT...AGREEMENT ON A SQUALL LINE MOVING ACROSS THE AREA WITH
HI-RES MODELS IS STRIKING. USED A BLEND OF THESE MODELS TO TRY AND
TIME TEMPO TSRA GROUPS THROUGH TAFS TONIGHT. BEHIND THIS AREA OF
TSRA...NOT BELIEVING THE GFS-LAMP WITH ITS WIDESPREAD IFR CIGS OR
LOWER...THOUGH SOME MVFR VIS IN BR/HZ IS MORE PLAUSIBLE FOR LATE
TONIGHT. BEHIND THE SQUALL...SHOULD SEE A BREAK IN CONVECTION
THROUGH 18Z...BEFORE MORE STORMS DEVELOP AFTER 18Z FRIDAY...LIKELY
OVER ERN SODAK/WRN MN.
KMSP...CONFIDENCE QUITE HIGH ON A STRONG TO SEVERE SQUALL LINE
IMPACTING THE FIELD TONIGHT. THERE ARE TIMING DIFFERENCES BETWEEN
HI-RES MODELS...BUT THEY ARE MINOR...WITH STORM PEGGED TO MOVE IN
TO MSP BETWEEN 5Z AND 8Z DEPENDING ON WHICH SOLUTION YOU LOOK AT.
FOR THIS AFTERNOON...ADDED A VCSH MENTION AT 23Z...AS IF SOMETHING
WERE TO DEVELOP OVER CENTRAL MN NORTH OF THE WARM FRONT THIS
AFTERNOON...THEN MSP WOULD GET A PRECURSOR ROUND OF STORMS BEFORE
THE MAIN SHOW ARRIVES TONIGHT. OUTSIDE OF TSRA...EXPECT MAINLY VFR
CONDS. FOR WINDS...THEY LOOK TO BE FAIRLY STEADY BETWEEN 180 AND
150...THOUGH WILL VARY CONSIDERABLY WITH ANY CONVECTION THAT MOVES
THROUGH.
/OUTLOOK FOR KMSP/
SAT...TSRA LIKELY. VFR OUTSIDE OF TSRA. WINDS SE 10KTS
SUN...TSRA LIKELY. VFR OUTSIDE OF TSRA. WINDS SSW 10-15 KTS.
MON...CHC TSRA. VFR OUTSIDE OF TSRA. WINDS S 5-10KTS.
&&
.HYDROLOGY...
ISSUED AT 345 AM CDT THU JUN 20 2013
A WET PATTERN IS EXPECTED ACROSS THE UPPER MISSISSIPPI RIVER
VALLEY REGION THROUGH EARLY NEXT WEEK WITH FLOODING POTENTIAL
VIRTUALLY EACH DAY DURING THIS PERIOD. A VERY SLOW MOVING UPPER
AIR PATTERN WILL ALLOW FOR SEVERAL ROUNDS OF SHOWERS AND
THUNDERSTORMS INTO EARLY NEXT WEEK. MOISTURE LEVELS WILL BE ON
THE RISE THROUGH FRIDAY AND THE WARM/HUMID AIR MASS WILL REMAIN
ENTRENCHED ACROSS THE REGION INTO MONDAY. DAILY PW VALUES ARE
PROGGED TO REACH OVER 1.75 INCHES THROUGH THE WEEKEND...WHICH IS
MORE THAN 2 STANDARD DEVIATIONS ABOVE NORMAL. FFG VALUES ARE QUITE
LOW WITH 1 HOUR VALUES AROUND 1.5 INCHES ACROSS THE MN RIVER
VALLEY AND SOUTH CENTRAL MN...WITH THREE HOUR VALUES IN THESE SAME
AREAS JUST UNDER 2 INCHES. AREAS THAT EXPERIENCE
THUNDERSTORMS...ESPECIALLY OVER THE WEEKEND...WILL LIKELY HAVE
RAINFALL RATES APPROACHING 2 INCHES PER HOUR. THEREFORE...IT WILL
NOT TAKE MUCH FOR LOCALIZED FLOODING TO OCCUR.
&&
.MPX WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...NONE.
&&
$$
SHORT TERM...AJZ
LONG TERM...JPC
AVIATION...MPG
HYDROLOGY...JPC
AREA FORECAST DISCUSSION
NWS DULUTH MN
1256 PM CDT THU JUN 20 2013
.AVIATION...
COMPLEX CONVECTIVE FORECAST THIS AFTERNOON...WITH MAIN FOCUS ON
TIMING AND INTENSITY OF THUNDERSTORMS. KDLH...KHIB WITHIN AN AREA
OF SHOWERS AND ISOLATED TSTSM THIS AFTERNOON WHICH WILL GRADUALLY
DIMINISH AND SHIFT EAST BY LATE AFTERNOON. KHYR HAS SOME ISOLATED
THUNDERSTORM ACITIVITY IN THE VICINITY WHICH IS EXPECTED TO
CONTINUE FOR THE NEXT FEW HOURS. KINL AND KBRH ARE IN THE CLEAR
FOR NOW. MORE THUNDERSTORMS ARE NOW INITIATING OVER EASTERN SOUTH
DAKOTA WHICH ARE EXPECTED TO ROLL EAST ALONG A WEAK WARM FRONT
TONIGHT. THE DAYTIME ACTIVITY SHOULD DIMINISH OVER THE NEXT FEW
HOURS AS THE MCS SHIFTS EAST. THE NEW THUNDERSTORMS ARE EXPECTED
TO ARRIVE AT THE TERMINALS SOMETIME AFTER 03Z THIS
EVENING DEPENDING ON LOCATION...THOUGH CANNOT RULE OUT EARLIER TIMING
AND HAVE PUT IN SOME VCTS GROUPS FOR A FEW HOURS AHEAD OF THAT.
THE STRONGER STORMS ARE EXPECTED TO BRING LOW END MVFR
CONDITIONS...POSSIBLY IFR CONDITIONS. THESE LOW CIGS ARE EXPECTED
TO LINGER INTO THE MORNING HOURS AND CLEARING IS NOT EXPECTED
UNTIL LATE FRIDAY MORNING.
&&
.PREV DISCUSSION... /ISSUED 1155 AM CDT THU JUN 20 2013/
UPDATE...
THE FOCUS REMAINS ON THE CURRENT SHOWERS AND THUNDERSTORMS ACROSS
THE NORTHLAND LATE THIS MORNING...BUT ALSO ON THE LIKELY NEXT
ROUND OF THUNDERSTORMS...POSSIBLY SEVERE...TONIGHT. SOME OF THE
LATEST 12Z GUIDANCE IS IN...SO UPDATED THE FORECAST THROUGH
TONIGHT.
IT APPEARS MCS OVER CENTRAL MINNESOTA IS WEAKENING LATE THIS
MORNING. IT STILL APPEARS THE REMAINING SHOWERS AND STORMS WITH
THIS MCS WILL GRADUALLY SPREAD EAST ACROSS THE NORTHLAND THROUGH
THIS AFTERNOON...BUT I LOWERED PCPN CHANCES SINCE THE SHOWERS ARE
NOT NEARLY AS ROBUST AS A COUPLE HOURS AGO.
THERE IS ALSO STILL A BAND OF SHOWERS AND STORMS STRETCHING ACROSS
THE NORTHERN FORECAST AREA. THIS BAND SEEMS TO BE HOLDING
TOGETHER...SO I INCREASED PCPN CHANCES THROUGH EARLY THIS
AFTERNOON. I STILL THINK THIS BAND MAY FALL APART OR MOVE NORTH OF
THE FORECAST AREA BY MID AFTERNOON.
IT APPEARS A WARM/STATIONARY FRONT MAY BE SETTING UP IN NW
WISCONSIN THANKS TO THE CONVERGENCE OF THE COOL NE FLOW OFF OF LAKE
SUPERIOR AND WARM SOUTHERLY FLOW WELL INLAND. THIS FRONT MAY BE
THE MECHANISM FOR MORE SHOWERS AND STORMS THIS AFTERNOON...SO I
KEPT HIGHER PCPN CHANCES FOR THIS AREA DURING THE AFTERNOON.
AS FOR TONIGHT...THE LATEST MODELS ARE STILL SUGGESTING ONE OR TWO
CLUSTERS OF THUNDERSTORMS...PERHAPS IN THE FORM OF AN MCS...WILL
FORM IN THE NORTHERN PLAINS AND/OR SOUTHERN MANITOBA...AND THEN
SPREAD EAST THROUGH OR NEAR THE NORTHLAND. THE LATEST GFS IS
PICKING UP ON THE TWO CLUSTER SCENARIO. AFTER READING THE STORM
PREDICTION CENTER DISCUSSION...IT APPEARS THE NORTHLAND MAY BE
UNDER THE GUN FOR A WIND AND HEAVY RAIN THREAT AS THOSE
THUNDERSTORMS THAT FORM THE NORTHERN PLAINS SPREAD INTO NORTHLAND
LATE THIS EVENING AND OVERNIGHT. PRECIPITABLE WATER VALUES WILL BE
BETWEEN 1.5 TO 2 INCHES...SO PLENTY OF MOISTURE IN THE OVERALL
ATMOSPHERE. I ADDED A SLIGHT CHANCE OF SEVERE THUNDERSTORMS AND
HEAVY RAIN TO THE WORDING IN THE FORECAST LATE THIS EVENING AND
AFTER MIDNIGHT.
PREV DISCUSSION... /ISSUED 933 AM CDT THU JUN 20 2013/
UPDATE...
THE MAIN FOCUS FOR THIS UPDATE IS ON THE CURRENT SHOWERS AND
STORMS ACROSS THE NORTHLAND...INCLUDING THE MCS IN CENTRAL AND
WESTERN MINNESOTA...AND HOW THE NORTHLAND WILL BE IMPACTED THROUGH
THIS AFTERNOON. THE MODELS ARE GENERALLY UNHELPFUL WITH THE
CURRENT SITUATION...SO I AM LEANING ON TRENDS. THE LATEST HRRR
SIMULATED REFLECTIVITY RUNS LOOK A BIT HELPFUL IN THAT IT THEY AT
LEAST REASONABLY CAPTURE THE CURRENT AREA OF RAIN AND
THUNDERSTORMS. THE HRRR RUNS THEN GENERALLY TAKE THIS MCS
GRADUALLY EAST THROUGH THE FORECAST AREA THROUGH THIS AFTERNOON. I
THINK THE EASTWARD PROGRESSION CAN BE EXPECTED. THEREFORE...I
INCREASED PCPN CHANCES ACROSS THE SOUTHERN FORECAST AREA THROUGH
THIS AFTERNOON.
I AM NOT CONFIDENT ABOUT WHAT IS CAUSING THE ARC
OF SHOWERS AND STORMS ACROSS THE NORTHERN AND EASTERN FORECAST
AREA THIS MORNING...BUT MY BEST GUESS IS LOW LEVEL FRONTOGENESIS.
THE 12Z NAM12 HAS A SIMILARLY LOCATED ARC OF ENHANCED
FRONTOGENESIS AT 900 HPA. SINCE THE NAM12 WASHES OUT THE
FRONTOGENETICAL BAND BY MID AFTERNOON...I ONLY ATTEMPTED TO TIME
AND INCREASE POPS FOR THE CURRENT SHOWER/STORM BAND THROUGH THE
EARLY AFTERNOON...AND THEN WENT WITH LOW POPS ACROSS THE NORTHERN
AND EASTERN FORECAST AREA FOR THE REST OF THE AFTERNOON. BASED ON
SPC MESOSCALE ANALYSIS...THESE STORMS ARE TAPPING INTO UP TO
SEVERAL HUNDRED J/KG OF CAPE...BUT LIMITED TO MARGINAL BULK SHEAR.
I EXPECT SOME STORMS COULD BE BECOME STRONG WITH SMALL
HAIL...GUSTY WINDS...AND BRIEF HEAVY RAIN...BUT SEVERE IS NOT
LIKELY.
THE CLOUD COVER BLANKETING THE NORTHLAND THIS MORNING BECAUSE OF
THE MCS AND OTHER SHOWERS AND STORMS MIGHT KEEP TEMPERATURES DOWN
A BIT TODAY. HOWEVER...WITH NOT MUCH NEW GUIDANCE IN YET...I ONLY
MADE MINOR TWEAKS TO THE FORECAST. I MIGHT NEED TO LOWER THE
TEMPERATURE FORECAST LATER THIS MORNING AFTER REVIEWING THE 12Z
GUIDANCE.
I PLAN ON ISSUING ANOTHER UPDATE TO THE FORECAST LATER THIS
MORNING TO UPDATE THE FORECAST THROUGH AT LEAST THIS EVENING.
PREV DISCUSSION... /ISSUED 650 AM CDT THU JUN 20 2013/
AVIATION...12Z TAF ISSUANCE
A LARGE THUNDERSTORM COMPLEX IN THE EASTERN DAKOTAS AND WESTERN
MINNESOTA HAS SPAWNED SOME STORMS IN THE BRD AREA. THERE WERE SOME
OTHER SCATTERED SOTRMS IN THE MN ARROWHEAD AND NWRN WI EARLY THIS
MORNING. THESE STORMS STORMS ARE EXPECTED TO SLOW DIMINISH THIS
MORNING...THEN MORE STORMS ARE LIKEY LATER TODAY...ESPECIALLY
TONIGHT. OUTSIDE OF THE STORMS CONDITIONS WILL BE VFR.
PREV DISCUSSION... /ISSUED 342 AM CDT THU JUN 20 2013/
CURRENT...LINE OF CONVECTION...SUB SEVERE...CONTINUES TO TRAIN
ALONG BORDERLAND FROM NRN ST LOUIS COUNTY TO THE GRAND MARAIS
VICINITY. THIS IS OCCURRING WITHIN THE PWAT AXIS PRODUCED BY THE
PREFRONTAL TROUGH AHEAD OF CANADIAN COLD FRONT. A FEW RAWS SITES
HAVE RECEIVED ABOUT A QUARTER TO HALF INCH AMOUNTS IN THE PAST
6 HRS. A SECOND AREA OF PRECIP IS SW OF CWA AND IS ASSOCIATED WITH
LLJ COMBINED WITH MIGRATORY SHORTWAVE. A FEW STORMS ARE APPROACHING
THE BRD LAKES REGION WITH AN ISOLATED CELL OVER SRN AITKIN COUNTY.
TODAY...MID LVL SHORTWAVE AND ASSOCIATED LLJ MAXIMUM WILL TRANSLATE
EAST AND WEAKEN THIS MORNING. OTHERWISE ANY ADDITIONAL SHORTWAVES
ALOFT ARE VERY DIFFICULT TO LOCATE. A STRENGTHENING WARM
ADVECTION REGIME WILL GENERATE INCREASING INSTABILITY ACROSS THE
CWA TODAY. BY 18Z ANY SBCIN HAS BEEN WIPED OUT OVER MOST OF CWA SO
ACTIVITY SHOULD INCREASE. HOWEVER PLACING SPECIFIC HIGHER POPS IS
TOUGH GIVEN NEBULOUS SFC BASED CONVERGENCE/LIFTING FEATURES OF
NOTE. PREFRONTAL TROUGH NEAR BORDER IS ABSORBED INTO OVERALL
SYNOPTIC PATTERN. THERE SHOULD BE A LAKE BREEZE BOUNDARY BUT EVEN
THE HIRES MDLS HAVE UNCERTAINTY OVER ITS LOCATION. CONVECTION THAT
DOES OCCUR SHOULD BE MARGINAL SEVERE BASED ON LACK OF ORGANIZED
DEEP LAYER SHEAR. LATEST SREF CALIBRATED PROBABILITY SVR INDICATES
GREATEST CHANCE OVER SWRN CWA IN AREA OF SBCAPE NEAR 3000/3500
J/KG.
TONIGHT/TOMORROW...MDL CONSENSUS IS THAT AN MCS WILL DEVELOP OVER
NRN PLAINS TONIGHT AND TRACK EAST OR ESE INTO MN BY MORNING. 85H
MSTR TRANSPORT AXIS SHIFTS INTO TWIN PORTS BY 12Z. BIG QUESTION AS
USUAL...WHERE IS THE BEST LOW LVL FOCUS TO FOCUS CORE OF HEAVIEST
PRECIP. GFS/EC SHOW A BIFURCATED QPF PATTERN SUGGESTING TWO AREAS
OF SIG CONVECTION OCCUR. SREF MCS MAINTENANCE PARAMETERS HINT AT
HIGHEST PRECIP VALUES SWINGING ALONG MPX/DLH BORDER. DAYSHIFT WILL
NEED TO ASSESS LATER DATA TO DETERMINE IF THERE ARE MORE CLEAR
SIGNALS OF FAVORED CHANNEL OF CONVECTION. MCS WILL MOVE EAST OF
AREA TOMORROW AND A RELATIVE MIN IN POPS WILL OCCUR AS ATMOSPHERE
RECHARGES FOR NEXT ROUND.
LONG TERM...FRIDAY NIGHT - WEDNESDAY
ONGOING CONVECTION NORTH OF WARM FRONT WILL BE THE MAIN WEATHER
FACTOR IN THE LONG TERM...
EXPECT THUNDERSTORMS TO CONTINUE TO FIRE ALONG AND NORTH OF THE WARM
FRONT...BUT WHERE IT EXACTLY ENDS UP IS STILL IN QUESTION...FARTHER
SOUTH OVER SOUTH CENTRAL MN/CENTRAL WI LIKE THE THE SREF AND AND
GFS OR FARTHER NORTH ALONG THE MPX/DLH CWA. THIS FRONT WILL BE FOCUS
OF NUMEROUS THUNDERSTORMS THROUGH SUNDAY AND POSSIBLY EVEN MONDAY.
STRONG MOISTURE TRANSPORT OVER THE FRONT AND ABUNDANT MOISTURE COULD
LEAD TO VERY HEAVY RAINFALL AMOUNTS AS STORMS TRAVERSE THE SAME
GENERAL AREA.
EAST WINDS NORTH OF THE FRONT...OVER THE FORECAST AREA...WILL
PROVIDE COOL AND VERY CLOUDY CONDITIONS IN THE HEAD OF THE LAKE AREA
AND LAKE SUPERIOR SHORE AREAS THROUGH THE WEEKEND.
THE WEATHER MAY QUIET DOWN A BIT FOR THE FIRST DAY OF THE WORK
WEEK....WITH MOMENTARY HIGH PRESSURE OVER NORTHERN MN...BUT THERE
COULD BE SOME LINGERING SHOWERS AND STORMS OVER WI. THEN ANOTHER
LOW AND ASSOCIATED FRONTAL SYSTEM WILL BRING ANOTHER ROUND OF
THUNDERSTORMS TUESDAY AND WEDNESDAY.
&&
.POINT TEMPS/POPS...
DLH 74 56 75 56 / 60 70 50 40
INL 79 61 76 58 / 40 70 30 30
BRD 82 67 80 64 / 90 70 30 60
HYR 80 67 81 64 / 60 70 70 50
ASX 76 58 75 53 / 50 70 70 40
&&
.DLH WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...NONE.
LS...NONE.
&&
$$
AVIATION...LE
AREA FORECAST DISCUSSION...UPDATED
NWS DULUTH MN
1155 AM CDT THU JUN 20 2013
.UPDATE...
THE FOCUS REMAINS ON THE CURRENT SHOWERS AND THUNDERSTORMS ACROSS
THE NORTHLAND LATE THIS MORNING...BUT ALSO ON THE LIKELY NEXT
ROUND OF THUNDERSTORMS...POSSIBLY SEVERE...TONIGHT. SOME OF THE
LATEST 12Z GUIDANCE IS IN...SO UPDATED THE FORECAST THROUGH
TONIGHT.
IT APPEARS MCS OVER CENTRAL MINNESOTA IS WEAKENING LATE THIS
MORNING. IT STILL APPEARS THE REMAINING SHOWERS AND STORMS WITH
THIS MCS WILL GRADUALLY SPREAD EAST ACROSS THE NORTHLAND THROUGH
THIS AFTERNOON...BUT I LOWERED PCPN CHANCES SINCE THE SHOWERS ARE
NOT NEARLY AS ROBUST AS A COUPLE HOURS AGO.
THERE IS ALSO STILL A BAND OF SHOWERS AND STORMS STRETCHING ACROSS
THE NORTHERN FORECAST AREA. THIS BAND SEEMS TO BE HOLDING
TOGETHER...SO I INCREASED PCPN CHANCES THROUGH EARLY THIS
AFTERNOON. I STILL THINK THIS BAND MAY FALL APART OR MOVE NORTH OF
THE FORECAST AREA BY MID AFTERNOON.
IT APPEARS A WARM/STATIONARY FRONT MAY BE SETTING UP IN NW
WISCONSIN THANKS TO THE CONVERGENCE OF THE COOL NE FLOW OFF OF LAKE
SUPERIOR AND WARM SOUTHERLY FLOW WELL INLAND. THIS FRONT MAY BE
THE MECHANISM FOR MORE SHOWERS AND STORMS THIS AFTERNOON...SO I
KEPT HIGHER PCPN CHANCES FOR THIS AREA DURING THE AFTERNOON.
AS FOR TONIGHT...THE LATEST MODELS ARE STILL SUGGESTING ONE OR TWO
CLUSTERS OF THUNDERSTORMS...PERHAPS IN THE FORM OF AN MCS...WILL
FORM IN THE NORTHERN PLAINS AND/OR SOUTHERN MANITOBA...AND THEN
SPREAD EAST THROUGH OR NEAR THE NORTHLAND. THE LATEST GFS IS
PICKING UP ON THE TWO CLUSTER SCENARIO. AFTER READING THE STORM
PREDICTION CENTER DISCUSSION...IT APPEARS THE NORTHLAND MAY BE
UNDER THE GUN FOR A WIND AND HEAVY RAIN THREAT AS THOSE
THUNDERSTORMS THAT FORM THE NORTHERN PLAINS SPREAD INTO NORTHLAND
LATE THIS EVENING AND OVERNIGHT. PRECIPITABLE WATER VALUES WILL BE
BETWEEN 1.5 TO 2 INCHES...SO PLENTY OF MOISTURE IN THE OVERALL
ATMOSPHERE. I ADDED A SLIGHT CHANCE OF SEVERE THUNDERSTORMS AND
HEAVY RAIN TO THE WORDING IN THE FORECAST LATE THIS EVENING AND
AFTER MIDNIGHT.
&&
.PREV DISCUSSION... /ISSUED 933 AM CDT THU JUN 20 2013/
UPDATE...
THE MAIN FOCUS FOR THIS UPDATE IS ON THE CURRENT SHOWERS AND
STORMS ACROSS THE NORTHLAND...INCLUDING THE MCS IN CENTRAL AND
WESTERN MINNESOTA...AND HOW THE NORTHLAND WILL BE IMPACTED THROUGH
THIS AFTERNOON. THE MODELS ARE GENERALLY UNHELPFUL WITH THE
CURRENT SITUATION...SO I AM LEANING ON TRENDS. THE LATEST HRRR
SIMULATED REFLECTIVITY RUNS LOOK A BIT HELPFUL IN THAT IT THEY AT
LEAST REASONABLY CAPTURE THE CURRENT AREA OF RAIN AND
THUNDERSTORMS. THE HRRR RUNS THEN GENERALLY TAKE THIS MCS
GRADUALLY EAST THROUGH THE FORECAST AREA THROUGH THIS AFTERNOON. I
THINK THE EASTWARD PROGRESSION CAN BE EXPECTED. THEREFORE...I
INCREASED PCPN CHANCES ACROSS THE SOUTHERN FORECAST AREA THROUGH
THIS AFTERNOON.
I AM NOT CONFIDENT ABOUT WHAT IS CAUSING THE ARC
OF SHOWERS AND STORMS ACROSS THE NORTHERN AND EASTERN FORECAST
AREA THIS MORNING...BUT MY BEST GUESS IS LOW LEVEL FRONTOGENESIS.
THE 12Z NAM12 HAS A SIMILARLY LOCATED ARC OF ENHANCED
FRONTOGENESIS AT 900 HPA. SINCE THE NAM12 WASHES OUT THE
FRONTOGENETICAL BAND BY MID AFTERNOON...I ONLY ATTEMPTED TO TIME
AND INCREASE POPS FOR THE CURRENT SHOWER/STORM BAND THROUGH THE
EARLY AFTERNOON...AND THEN WENT WITH LOW POPS ACROSS THE NORTHERN
AND EASTERN FORECAST AREA FOR THE REST OF THE AFTERNOON. BASED ON
SPC MESOSCALE ANALYSIS...THESE STORMS ARE TAPPING INTO UP TO
SEVERAL HUNDRED J/KG OF CAPE...BUT LIMITED TO MARGINAL BULK SHEAR.
I EXPECT SOME STORMS COULD BE BECOME STRONG WITH SMALL
HAIL...GUSTY WINDS...AND BRIEF HEAVY RAIN...BUT SEVERE IS NOT
LIKELY.
THE CLOUD COVER BLANKETING THE NORTHLAND THIS MORNING BECAUSE OF
THE MCS AND OTHER SHOWERS AND STORMS MIGHT KEEP TEMPERATURES DOWN
A BIT TODAY. HOWEVER...WITH NOT MUCH NEW GUIDANCE IN YET...I ONLY
MADE MINOR TWEAKS TO THE FORECAST. I MIGHT NEED TO LOWER THE
TEMPERATURE FORECAST LATER THIS MORNING AFTER REVIEWING THE 12Z
GUIDANCE.
I PLAN ON ISSUING ANOTHER UPDATE TO THE FORECAST LATER THIS
MORNING TO UPDATE THE FORECAST THROUGH AT LEAST THIS EVENING.
PREV DISCUSSION... /ISSUED 650 AM CDT THU JUN 20 2013/
AVIATION...12Z TAF ISSUANCE
A LARGE THUNDERSTORM COMPLEX IN THE EASTERN DAKOTAS AND WESTERN
MINNESOTA HAS SPAWNED SOME STORMS IN THE BRD AREA. THERE WERE SOME
OTHER SCATTERED SOTRMS IN THE MN ARROWHEAD AND NWRN WI EARLY THIS
MORNING. THESE STORMS STORMS ARE EXPECTED TO SLOW DIMINISH THIS
MORNING...THEN MORE STORMS ARE LIKEY LATER TODAY...ESPECIALLY
TONIGHT. OUTSIDE OF THE STORMS CONDITIONS WILL BE VFR.
PREV DISCUSSION... /ISSUED 342 AM CDT THU JUN 20 2013/
CURRENT...LINE OF CONVECTION...SUB SEVERE...CONTINUES TO TRAIN
ALONG BORDERLAND FROM NRN ST LOUIS COUNTY TO THE GRAND MARAIS
VICINITY. THIS IS OCCURRING WITHIN THE PWAT AXIS PRODUCED BY THE
PREFRONTAL TROUGH AHEAD OF CANADIAN COLD FRONT. A FEW RAWS SITES
HAVE RECEIVED ABOUT A QUARTER TO HALF INCH AMOUNTS IN THE PAST
6 HRS. A SECOND AREA OF PRECIP IS SW OF CWA AND IS ASSOCIATED WITH
LLJ COMBINED WITH MIGRATORY SHORTWAVE. A FEW STORMS ARE APPROACHING
THE BRD LAKES REGION WITH AN ISOLATED CELL OVER SRN AITKIN COUNTY.
TODAY...MID LVL SHORTWAVE AND ASSOCIATED LLJ MAXIMUM WILL TRANSLATE
EAST AND WEAKEN THIS MORNING. OTHERWISE ANY ADDITIONAL SHORTWAVES
ALOFT ARE VERY DIFFICULT TO LOCATE. A STRENGTHENING WARM
ADVECTION REGIME WILL GENERATE INCREASING INSTABILITY ACROSS THE
CWA TODAY. BY 18Z ANY SBCIN HAS BEEN WIPED OUT OVER MOST OF CWA SO
ACTIVITY SHOULD INCREASE. HOWEVER PLACING SPECIFIC HIGHER POPS IS
TOUGH GIVEN NEBULOUS SFC BASED CONVERGENCE/LIFTING FEATURES OF
NOTE. PREFRONTAL TROUGH NEAR BORDER IS ABSORBED INTO OVERALL
SYNOPTIC PATTERN. THERE SHOULD BE A LAKE BREEZE BOUNDARY BUT EVEN
THE HIRES MDLS HAVE UNCERTAINTY OVER ITS LOCATION. CONVECTION THAT
DOES OCCUR SHOULD BE MARGINAL SEVERE BASED ON LACK OF ORGANIZED
DEEP LAYER SHEAR. LATEST SREF CALIBRATED PROBABILITY SVR INDICATES
GREATEST CHANCE OVER SWRN CWA IN AREA OF SBCAPE NEAR 3000/3500
J/KG.
TONIGHT/TOMORROW...MDL CONSENSUS IS THAT AN MCS WILL DEVELOP OVER
NRN PLAINS TONIGHT AND TRACK EAST OR ESE INTO MN BY MORNING. 85H
MSTR TRANSPORT AXIS SHIFTS INTO TWIN PORTS BY 12Z. BIG QUESTION AS
USUAL...WHERE IS THE BEST LOW LVL FOCUS TO FOCUS CORE OF HEAVIEST
PRECIP. GFS/EC SHOW A BIFURCATED QPF PATTERN SUGGESTING TWO AREAS
OF SIG CONVECTION OCCUR. SREF MCS MAINTENANCE PARAMETERS HINT AT
HIGHEST PRECIP VALUES SWINGING ALONG MPX/DLH BORDER. DAYSHIFT WILL
NEED TO ASSESS LATER DATA TO DETERMINE IF THERE ARE MORE CLEAR
SIGNALS OF FAVORED CHANNEL OF CONVECTION. MCS WILL MOVE EAST OF
AREA TOMORROW AND A RELATIVE MIN IN POPS WILL OCCUR AS ATMOSPHERE
RECHARGES FOR NEXT ROUND.
LONG TERM...FRIDAY NIGHT - WEDNESDAY
ONGOING CONVECTION NORTH OF WARM FRONT WILL BE THE MAIN WEATHER
FACTOR IN THE LONG TERM...
EXPECT THUNDERSTORMS TO CONTINUE TO FIRE ALONG AND NORTH OF THE WARM
FRONT...BUT WHERE IT EXACTLY ENDS UP IS STILL IN QUESTION...FARTHER
SOUTH OVER SOUTH CENTRAL MN/CENTRAL WI LIKE THE THE SREF AND AND
GFS OR FARTHER NORTH ALONG THE MPX/DLH CWA. THIS FRONT WILL BE FOCUS
OF NUMEROUS THUNDERSTORMS THROUGH SUNDAY AND POSSIBLY EVEN MONDAY.
STRONG MOISTURE TRANSPORT OVER THE FRONT AND ABUNDANT MOISTURE COULD
LEAD TO VERY HEAVY RAINFALL AMOUNTS AS STORMS TRAVERSE THE SAME
GENERAL AREA.
EAST WINDS NORTH OF THE FRONT...OVER THE FORECAST AREA...WILL
PROVIDE COOL AND VERY CLOUDY CONDITIONS IN THE HEAD OF THE LAKE AREA
AND LAKE SUPERIOR SHORE AREAS THROUGH THE WEEKEND.
THE WEATHER MAY QUIET DOWN A BIT FOR THE FIRST DAY OF THE WORK
WEEK....WITH MOMENTARY HIGH PRESSURE OVER NORTHERN MN...BUT THERE
COULD BE SOME LINGERING SHOWERS AND STORMS OVER WI. THEN ANOTHER
LOW AND ASSOCIATED FRONTAL SYSTEM WILL BRING ANOTHER ROUND OF
THUNDERSTORMS TUESDAY AND WEDNESDAY.
&&
.POINT TEMPS/POPS...
DLH 74 56 75 56 / 60 70 50 40
INL 79 61 76 58 / 40 70 40 30
BRD 82 67 80 64 / 90 70 20 60
HYR 80 67 81 64 / 60 70 60 50
ASX 76 58 75 53 / 50 70 60 40
&&
.DLH WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...NONE.
LS...NONE.
&&
$$
SHORT TERM...GROCHOCINSKI
AREA FORECAST DISCUSSION
NWS DULUTH MN
933 AM CDT THU JUN 20 2013
.UPDATE...
THE MAIN FOCUS FOR THIS UPDATE IS ON THE CURRENT SHOWERS AND
STORMS ACROSS THE NORTHLAND...INCLUDING THE MCS IN CENTRAL AND
WESTERN MINNESOTA...AND HOW THE NORTHLAND WILL BE IMPACTED THROUGH
THIS AFTERNOON. THE MODELS ARE GENERALLY UNHELPFUL WITH THE
CURRENT SITUATION...SO I AM LEANING ON TRENDS. THE LATEST HRRR
SIMULATED REFLECTIVITY RUNS LOOK A BIT HELPFUL IN THAT IT THEY AT
LEAST REASONABLY CAPTURE THE CURRENT AREA OF RAIN AND
THUNDERSTORMS. THE HRRR RUNS THEN GENERALLY TAKE THIS MCS
GRADUALLY EAST THROUGH THE FORECAST AREA THROUGH THIS AFTERNOON. I
THINK THE EASTWARD PROGRESSION CAN BE EXPECTED. THEREFORE...I
INCREASED PCPN CHANCES ACROSS THE SOUTHERN FORECAST AREA THROUGH
THIS AFTERNOON.
I AM NOT CONFIDENT ABOUT WHAT IS CAUSING THE ARC
OF SHOWERS AND STORMS ACROSS THE NORTHERN AND EASTERN FORECAST
AREA THIS MORNING...BUT MY BEST GUESS IS LOW LEVEL FRONTOGENESIS.
THE 12Z NAM12 HAS A SIMILARLY LOCATED ARC OF ENHANCED
FRONTOGENESIS AT 900 HPA. SINCE THE NAM12 WASHES OUT THE
FRONTOGENETICAL BAND BY MID AFTERNOON...I ONLY ATTEMPTED TO TIME
AND INCREASE POPS FOR THE CURRENT SHOWER/STORM BAND THROUGH THE
EARLY AFTERNOON...AND THEN WENT WITH LOW POPS ACROSS THE NORTHERN
AND EASTERN FORECAST AREA FOR THE REST OF THE AFTERNOON. BASED ON
SPC MESOSCALE ANALYSIS...THESE STORMS ARE TAPPING INTO UP TO
SEVERAL HUNDRED J/KG OF CAPE...BUT LIMITED TO MARGINAL BULK SHEAR.
I EXPECT SOME STORMS COULD BE BECOME STRONG WITH SMALL
HAIL...GUSTY WINDS...AND BRIEF HEAVY RAIN...BUT SEVERE IS NOT
LIKELY.
THE CLOUD COVER BLANKETING THE NORTHLAND THIS MORNING BECAUSE OF
THE MCS AND OTHER SHOWERS AND STORMS MIGHT KEEP TEMPERATURES DOWN
A BIT TODAY. HOWEVER...WITH NOT MUCH NEW GUIDANCE IN YET...I ONLY
MADE MINOR TWEAKS TO THE FORECAST. I MIGHT NEED TO LOWER THE
TEMPERATURE FORECAST LATER THIS MORNING AFTER REVIEWING THE 12Z
GUIDANCE.
I PLAN ON ISSUING ANOTHER UPDATE TO THE FORECAST LATER THIS
MORNING TO UPDATE THE FORECAST THROUGH AT LEAST THIS EVENING.
&&
.PREV DISCUSSION... /ISSUED 650 AM CDT THU JUN 20 2013/
AVIATION...12Z TAF ISSUANCE
A LARGE THUNDERSTORM COMPLEX IN THE EASTERN DAKOTAS AND WESTERN
MINNESOTA HAS SPAWNED SOME STORMS IN THE BRD AREA. THERE WERE SOME
OTHER SCATTERED SOTRMS IN THE MN ARROWHEAD AND NWRN WI EARLY THIS
MORNING. THESE STORMS STORMS ARE EXPECTED TO SLOW DIMINISH THIS
MORNING...THEN MORE STORMS ARE LIKEY LATER TODAY...ESPECIALLY
TONIGHT. OUTSIDE OF THE STORMS CONDITIONS WILL BE VFR.
PREV DISCUSSION... /ISSUED 342 AM CDT THU JUN 20 2013/
CURRENT...LINE OF CONVECTION...SUB SEVERE...CONTINUES TO TRAIN
ALONG BORDERLAND FROM NRN ST LOUIS COUNTY TO THE GRAND MARAIS
VICINITY. THIS IS OCCURRING WITHIN THE PWAT AXIS PRODUCED BY THE
PREFRONTAL TROUGH AHEAD OF CANADIAN COLD FRONT. A FEW RAWS SITES
HAVE RECEIVED ABOUT A QUARTER TO HALF INCH AMOUNTS IN THE PAST
6 HRS. A SECOND AREA OF PRECIP IS SW OF CWA AND IS ASSOCIATED WITH
LLJ COMBINED WITH MIGRATORY SHORTWAVE. A FEW STORMS ARE APPROACHING
THE BRD LAKES REGION WITH AN ISOLATED CELL OVER SRN AITKIN COUNTY.
TODAY...MID LVL SHORTWAVE AND ASSOCIATED LLJ MAXIMUM WILL TRANSLATE
EAST AND WEAKEN THIS MORNING. OTHERWISE ANY ADDITIONAL SHORTWAVES
ALOFT ARE VERY DIFFICULT TO LOCATE. A STRENGTHENING WARM
ADVECTION REGIME WILL GENERATE INCREASING INSTABILITY ACROSS THE
CWA TODAY. BY 18Z ANY SBCIN HAS BEEN WIPED OUT OVER MOST OF CWA SO
ACTIVITY SHOULD INCREASE. HOWEVER PLACING SPECIFIC HIGHER POPS IS
TOUGH GIVEN NEBULOUS SFC BASED CONVERGENCE/LIFTING FEATURES OF
NOTE. PREFRONTAL TROUGH NEAR BORDER IS ABSORBED INTO OVERALL
SYNOPTIC PATTERN. THERE SHOULD BE A LAKE BREEZE BOUNDARY BUT EVEN
THE HIRES MDLS HAVE UNCERTAINTY OVER ITS LOCATION. CONVECTION THAT
DOES OCCUR SHOULD BE MARGINAL SEVERE BASED ON LACK OF ORGANIZED
DEEP LAYER SHEAR. LATEST SREF CALIBRATED PROBABILITY SVR INDICATES
GREATEST CHANCE OVER SWRN CWA IN AREA OF SBCAPE NEAR 3000/3500
J/KG.
TONIGHT/TOMORROW...MDL CONSENSUS IS THAT AN MCS WILL DEVELOP OVER
NRN PLAINS TONIGHT AND TRACK EAST OR ESE INTO MN BY MORNING. 85H
MSTR TRANSPORT AXIS SHIFTS INTO TWIN PORTS BY 12Z. BIG QUESTION AS
USUAL...WHERE IS THE BEST LOW LVL FOCUS TO FOCUS CORE OF HEAVIEST
PRECIP. GFS/EC SHOW A BIFURCATED QPF PATTERN SUGGESTING TWO AREAS
OF SIG CONVECTION OCCUR. SREF MCS MAINTENANCE PARAMETERS HINT AT
HIGHEST PRECIP VALUES SWINGING ALONG MPX/DLH BORDER. DAYSHIFT WILL
NEED TO ASSESS LATER DATA TO DETERMINE IF THERE ARE MORE CLEAR
SIGNALS OF FAVORED CHANNEL OF CONVECTION. MCS WILL MOVE EAST OF
AREA TOMORROW AND A RELATIVE MIN IN POPS WILL OCCUR AS ATMOSPHERE
RECHARGES FOR NEXT ROUND.
LONG TERM...FRIDAY NIGHT - WEDNESDAY
ONGOING CONVECTION NORTH OF WARM FRONT WILL BE THE MAIN WEATHER
FACTOR IN THE LONG TERM...
EXPECT THUNDERSTORMS TO CONTINUE TO FIRE ALONG AND NORTH OF THE WARM
FRONT...BUT WHERE IT EXACTLY ENDS UP IS STILL IN QUESTION...FARTHER
SOUTH OVER SOUTH CENTRAL MN/CENTRAL WI LIKE THE THE SREF AND AND
GFS OR FARTHER NORTH ALONG THE MPX/DLH CWA. THIS FRONT WILL BE FOCUS
OF NUMEROUS THUNDERSTORMS THROUGH SUNDAY AND POSSIBLY EVEN MONDAY.
STRONG MOISTURE TRANSPORT OVER THE FRONT AND ABUNDANT MOISTURE COULD
LEAD TO VERY HEAVY RAINFALL AMOUNTS AS STORMS TRAVERSE THE SAME
GENERAL AREA.
EAST WINDS NORTH OF THE FRONT...OVER THE FORECAST AREA...WILL
PROVIDE COOL AND VERY CLOUDY CONDITIONS IN THE HEAD OF THE LAKE AREA
AND LAKE SUPERIOR SHORE AREAS THROUGH THE WEEKEND.
THE WEATHER MAY QUIET DOWN A BIT FOR THE FIRST DAY OF THE WORK
WEEK....WITH MOMENTARY HIGH PRESSURE OVER NORTHERN MN...BUT THERE
COULD BE SOME LINGERING SHOWERS AND STORMS OVER WI. THEN ANOTHER
LOW AND ASSOCIATED FRONTAL SYSTEM WILL BRING ANOTHER ROUND OF
THUNDERSTORMS TUESDAY AND WEDNESDAY.
&&
.POINT TEMPS/POPS...
DLH 75 57 75 56 / 60 70 50 40
INL 80 60 76 58 / 50 70 40 30
BRD 81 67 80 64 / 90 70 20 60
HYR 80 63 81 64 / 50 70 60 50
ASX 76 57 75 53 / 50 70 60 40
&&
.DLH WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...NONE.
LS...NONE.
&&
$$
SHORT TERM...GROCHOCINSKI
AREA FORECAST DISCUSSION...UPDATED
NWS ST LOUIS MO
935 PM CDT FRI JUN 21 2013
.UPDATE...
ISSUED AT 933 PM CDT FRI JUN 21 2013
SCANT CONVECTION THAT DOTTED OUR S IL COUNTIES EARLY THIS EVENING
HAS DISSIPATED...AND AM EXTREMELY HARD-PRESSED TO DISCERN ANY MECHANISM
FOR REDEVELOPMENT OVERNIGHT. STRONGEST 850MB WAA WILL BE FOCUSED
WELL TO OUR N THROUGHOUT THE NIGHT...AND THE MID LEVEL WAA THAT
WAS RESPONSIBLE FOR LAST NIGHTS CONVECTION IS MUCH...MUCH WEAKER
OVER OUR AREA THAN IT WAS LAST NIGHT. SO...WILL GO WITH A DRY
FORECAST FOR REMAINDER OF THE NIGHT WITH SOME OCCASIONAL MID AND
HIGH LEVEL CLOUDINESS. TEMPERATURE TRENDS STILL LOOKING GOOD.
ZONES WILL BE OUT IN A SECOND.
TRUETT
&&
.SHORT TERM...(THROUGH LATE TONIGHT)
ISSUED AT 323 PM CDT FRI JUN 21 2013
THE MAIN SHORT-TERM CONCERN IS THE MCS GENERATED OUTFLOW BOUNDARY
CURRENTLY DROPPING S/SEWD THROUGH CENTRAL IL. WHILE THE MCS
ITSELF IS MOVING SEWD...THE RUC 0-3 KM AND 0-6 KM SHEAR VECTORS
SUGGEST THAT AS LONG AS THIS BOUNDARY MAINTAINS ITS IDENTITY IT
SHOULD CONTINUE TO DROP S/SEWD AND AT LEAST IMPACT AREAS EAST OF
THE MS RIVER LATE THIS AFTERNOON INTO EARLY THIS EVENING. THE AIR
MASS AHEAD OF THIS BOUNDARY IS WEAKLY CAPPED WITH SBCAPE INCREASING
FROM 2000 J/KG IN CENTRAL IL TO NEAR 4000 J/KG ALONG THE RIVER.
THIS COMBINATION OF INSTABILITY/CAPPING AND CONVERGENCE WITH THE
BOUNDARY SUPPORTS A GREATER CHANCE OF MORE ORGANIZED CONVECTION
ACROSS SOUTH CENTRAL IL WHERE SCATTERED THUNDERSTORMS ARE POSSIBLE.
ELSEWHERE THROUGH SUNSET ANY THREAT OF SHOWERS/THUNDERSTORMS WILL
BE ISOLATED PULSE TYPE ACTIVITY ASSOCIATED WITH DIURNAL HEATING. I
THINK THERE WILL THEN BE A LULL FROM SAY AROUND 02-03Z TIL 08Z OR
SO...THEN ANOTHER CHANCE OF SHOWERS AND THUNDERSTORMS...PRIMARILY
ACROSS ERN MO INTO SW/SC IL... ASSOCIATED WITH LOW-MID LEVEL WAA
VIA THE SWLY LLJ AND STEEP MID LEVEL LAPSE RATES. OVERNIGHT LOWS
WILL BE QUITE MILD AND ABOVE SEASONABLE NORMS.
GLASS
.LONG TERM...(SATURDAY THROUGH NEXT FRIDAY)
ISSUED AT 323 PM CDT FRI JUN 21 2013
(SATURDAY THROUGH MONDAY)
BROKEN RECORD FOR WEATHER PATTERN AS WE REMAIN IN WARM SECTOR ON
SATURDAY WITH SOME WEAK INSTABILITY AND PLENTY OF MOISTURE. SO ANY
OLD OUTFLOW BOUNDARY...ETC COULD TRIGGER ISOLATED THUNDERSTORM
DEVELOPMENT...SO KEPT SLIGHT CHANCE POPS FOR SATURDAY AFTERNOON.
OTHERWISE...HIGHS WILL BE IN THE UPPER 80S TO LOW 90S...POSSIBLY IN
THE MID 90S IN THE STL METRO AREA. LOWS SATURDAY NIGHT WILL BE IN
THE LOW 70S.
UPPER RIDGE BUILDS IN A BIT STRONGER ON SUNDAY...SO THUNDERSTORM
CHANCES DIMINISH. BUT HOT AND HUMID CONDITIONS TO PERSIST WITH HIGHS
IN THE UPPER 80S TO LOW 90S. ON SUNDAY NIGHT AND MONDAY...UPPER
RIDGE BEGINS TO WEAKEN AGAIN AS NEXT WEATHER SYSTEM APPROACHES THE
REGION. MCS EXPECTED TO DEVELOP ALONG BOUNDARY OVER IOWA...WITH
SOUTHERN FRINGES SLIDING THROUGH NORTHERN MO/WEST CENTRAL IL ON
MONDAY. LOWS SUNDAY NIGHT WILL BE IN THE LOW TO MID 70S WITH HIGHS
ON MONDAY IN THE UPPER 80S TO LOW 90S.
(MONDAY NIGHT THROUGH FRIDAY)
EXTENDED MODELS CONTINUE TO SLOW DOWN PASSAGE OF THIS COLD
FRONT...SO HOT AND HUMID CONDITIONS TO PERSIST THROUGH THURSDAY WITH
HIGHS EACH DAY IN THE UPPER 80S TO MID 90S. BY WEDNESDAY
NIGHT...COLD FRONT MOVES CLOSER TO AREA WITH CHANCES OF SHOWERS AND
THUNDERSTORMS FOR PORTIONS OF THE AREA WEDNESDAY NIGHT AND THURSDAY.
CONFIDENCE ON TIMING OF FRONTAL PASSAGE LOW...SO FOR NOW HAVE SILENT
SLIGHT CHANCE POPS IN FOR AREA THURSDAY NIGHT AND PORTIONS OF THE
AREA FRIDAY UNTIL FRONT FINALLY MOVES THROUGH. BY FRIDAY HIGHS WILL
BE IN THE MID TO UPPER 80S.
BYRD
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z SATURDAY EVENING)
ISSUED AT 556 PM CDT FRI JUN 21 2013
THE STRONG MIDLEVEL RIDGE WILL CONTINUE TO CONTROL THE WEATHER
PATTERN THROUGH SATURDAY NIGHT. INSTABILITY WILL BE PLENTIFUL
TOMORROW AFTERNOON...BUT COVERAGE SHOULD ONCE AGAIN REMAIN
ISOLATED SINCE ANY LARGE-SCALE FORCING MECHANISM FOR ASCENT SHOULD
BE LACKING. THEREFORE...HAVE CONTINUED TO LEAVE ANY MENTION OF TS
0R SHRA OUT OF TAFS FOR NOW. DIURNAL CU SHOULD DEVELOP WITH BASES
AROUND 5000 FEET TOMORROW AROUND MIDDAY WITH WINDS THROUGHOUT THE
VALID TAF PERIOD REMAINING OUT OF THE SOUTH.
SPECIFICS FOR KSTL...
THE STRONG MIDLEVEL RIDGE WILL CONTINUE TO CONTROL THE WEATHER
PATTERN THROUGH SATURDAY NIGHT FOR LAMBERT FIELD. INSTABILITY WILL BE
PLENTIFUL TOMORROW AFTERNOON...BUT COVERAGE OF ANY STORMS WHICH
WOULD DEVELOP SHOULD ONCE AGAIN REMAIN ISOLATED SINCE ANY LARGE-
SCALE FORCING MECHANISM FOR ASCENT SHOULD BE LACKING.
THEREFORE...HAVE CONTINUED TO LEAVE ANY MENTION OF TS 0R SHRA OUT
OF TAF FOR NOW. DIURNAL CU SHOULD DEVELOP WITH BASES AROUND 5000
FEET TOMORROW AROUND MIDDAY WITH WINDS THROUGHOUT THE VALID TAF
PERIOD REMAINING OUT OF THE SOUTH.
GOSSELIN
&&
.LSX WATCHES/WARNINGS/ADVISORIES...
MO...NONE.
IL...NONE.
&&
$$
WFO LSX
AREA FORECAST DISCUSSION...UPDATED
NWS ST LOUIS MO
640 PM CDT FRI JUN 21 2013
.UPDATE...
ISSUED AT 628 PM CDT FRI JUN 21 2013
MOST ACTIVE PART OF CENTRAL IL MCS NOW WORKING ITS WAY INTO
WESTERN IN. MEANWHILE...CONVECTIVE ELEMENTS DROPPING FROM CENTRAL
INTO S IL HAVE WEAKENED CONSIDERABLY OVER THE LAST COUPLE OF
HOURS...AND RADAR IMAGERY INDICATES THAT OUTFLOW HAS STOPPED ITS
SOUTHWARD PROPAGATION WITH SUGGESTIONS THAT IS HAS BEGUN TO
RETROGRADE BACK TO THE NORTH. THESE TRENDS SUGGEST THAT HIGH
CHANCE POPS IN OUR E COUNTIES ARE A BIT TOO OPTIMISTIC. GIVEN
UNSTABLE NATURE OF AMS HAVEN`T TOTALLY DROPPED MENTION OF
THUNDERSTORMS BUT DID BACK OFF TO 30 POPS OVER OUR FAR S IL
COUNTIES FOR THE NEXT FEW HOURS...WITH SLIGHT CHANCE POPS OVER THE
REMAINDER OF THE CWA CAPTURING THE STRAY SHOWERS/ECHOES THAT
SHOULD CONTINUE TO POP UP FOR SEVERAL MORE HOURS.
TRUETT
&&
.SHORT TERM...(THROUGH LATE TONIGHT)
ISSUED AT 323 PM CDT FRI JUN 21 2013
THE MAIN SHORT-TERM CONCERN IS THE MCS GENERATED OUTFLOW BOUNDARY
CURRENTLY DROPPING S/SEWD THROUGH CENTRAL IL. WHILE THE MCS
ITSELF IS MOVING SEWD...THE RUC 0-3 KM AND 0-6 KM SHEAR VECTORS
SUGGEST THAT AS LONG AS THIS BOUNDARY MAINTAINS ITS IDENTITY IT
SHOULD CONTINUE TO DROP S/SEWD AND AT LEAST IMPACT AREAS EAST OF
THE MS RIVER LATE THIS AFTERNOON INTO EARLY THIS EVENING. THE AIR
MASS AHEAD OF THIS BOUNDARY IS WEAKLY CAPPED WITH SBCAPE INCREASING
FROM 2000 J/KG IN CENTRAL IL TO NEAR 4000 J/KG ALONG THE RIVER.
THIS COMBINATION OF INSTABILITY/CAPPING AND CONVERGENCE WITH THE
BOUNDARY SUPPORTS A GREATER CHANCE OF MORE ORGANIZED CONVECTION
ACROSS SOUTH CENTRAL IL WHERE SCATTERED THUNDERSTORMS ARE POSSIBLE.
ELSEWHERE THROUGH SUNSET ANY THREAT OF SHOWERS/THUNDERSTORMS WILL
BE ISOLATED PULSE TYPE ACTIVITY ASSOCIATED WITH DIURNAL HEATING. I
THINK THERE WILL THEN BE A LULL FROM SAY AROUND 02-03Z TIL 08Z OR
SO...THEN ANOTHER CHANCE OF SHOWERS AND THUNDERSTORMS...PRIMARILY
ACROSS ERN MO INTO SW/SC IL... ASSOCIATED WITH LOW-MID LEVEL WAA
VIA THE SWLY LLJ AND STEEP MID LEVEL LAPSE RATES. OVERNIGHT LOWS
WILL BE QUITE MILD AND ABOVE SEASONABLE NORMS.
GLASS
.LONG TERM...(SATURDAY THROUGH NEXT FRIDAY)
ISSUED AT 323 PM CDT FRI JUN 21 2013
(SATURDAY THROUGH MONDAY)
BROKEN RECORD FOR WEATHER PATTERN AS WE REMAIN IN WARM SECTOR ON
SATURDAY WITH SOME WEAK INSTABILITY AND PLENTY OF MOISTURE. SO ANY
OLD OUTFLOW BOUNDARY...ETC COULD TRIGGER ISOLATED THUNDERSTORM
DEVELOPMENT...SO KEPT SLIGHT CHANCE POPS FOR SATURDAY AFTERNOON.
OTHERWISE...HIGHS WILL BE IN THE UPPER 80S TO LOW 90S...POSSIBLY IN
THE MID 90S IN THE STL METRO AREA. LOWS SATURDAY NIGHT WILL BE IN
THE LOW 70S.
UPPER RIDGE BUILDS IN A BIT STRONGER ON SUNDAY...SO THUNDERSTORM
CHANCES DIMINISH. BUT HOT AND HUMID CONDITIONS TO PERSIST WITH HIGHS
IN THE UPPER 80S TO LOW 90S. ON SUNDAY NIGHT AND MONDAY...UPPER
RIDGE BEGINS TO WEAKEN AGAIN AS NEXT WEATHER SYSTEM APPROACHES THE
REGION. MCS EXPECTED TO DEVELOP ALONG BOUNDARY OVER IOWA...WITH
SOUTHERN FRINGES SLIDING THROUGH NORTHERN MO/WEST CENTRAL IL ON
MONDAY. LOWS SUNDAY NIGHT WILL BE IN THE LOW TO MID 70S WITH HIGHS
ON MONDAY IN THE UPPER 80S TO LOW 90S.
(MONDAY NIGHT THROUGH FRIDAY)
EXTENDED MODELS CONTINUE TO SLOW DOWN PASSAGE OF THIS COLD
FRONT...SO HOT AND HUMID CONDITIONS TO PERSIST THROUGH THURSDAY WITH
HIGHS EACH DAY IN THE UPPER 80S TO MID 90S. BY WEDNESDAY
NIGHT...COLD FRONT MOVES CLOSER TO AREA WITH CHANCES OF SHOWERS AND
THUNDERSTORMS FOR PORTIONS OF THE AREA WEDNESDAY NIGHT AND THURSDAY.
CONFIDENCE ON TIMING OF FRONTAL PASSAGE LOW...SO FOR NOW HAVE SILENT
SLIGHT CHANCE POPS IN FOR AREA THURSDAY NIGHT AND PORTIONS OF THE
AREA FRIDAY UNTIL FRONT FINALLY MOVES THROUGH. BY FRIDAY HIGHS WILL
BE IN THE MID TO UPPER 80S.
BYRD
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z SATURDAY EVENING)
ISSUED AT 556 PM CDT FRI JUN 21 2013
THE STRONG MIDLEVEL RIDGE WILL CONTINUE TO CONTROL THE WEATHER
PATTERN THROUGH SATURDAY NIGHT. INSTABILITY WILL BE PLENTIFUL
TOMORROW AFTERNOON...BUT COVERAGE SHOULD ONCE AGAIN REMAIN
ISOLATED SINCE ANY LARGE-SCALE FORCING MECHANISM FOR ASCENT SHOULD
BE LACKING. THEREFORE...HAVE CONTINUED TO LEAVE ANY MENTION OF TS
0R SHRA OUT OF TAFS FOR NOW. DIURNAL CU SHOULD DEVELOP WITH BASES
AROUND 5000 FEET TOMORROW AROUND MIDDAY WITH WINDS THROUGHOUT THE
VALID TAF PERIOD REMAINING OUT OF THE SOUTH.
SPECIFICS FOR KSTL...
THE STRONG MIDLEVEL RIDGE WILL CONTINUE TO CONTROL THE WEATHER
PATTERN THROUGH SATURDAY NIGHT FOR LAMBERT FIELD. INSTABILITY WILL BE
PLENTIFUL TOMORROW AFTERNOON...BUT COVERAGE OF ANY STORMS WHICH
WOULD DEVELOP SHOULD ONCE AGAIN REMAIN ISOLATED SINCE ANY LARGE-
SCALE FORCING MECHANISM FOR ASCENT SHOULD BE LACKING.
THEREFORE...HAVE CONTINUED TO LEAVE ANY MENTION OF TS 0R SHRA OUT
OF TAF FOR NOW. DIURNAL CU SHOULD DEVELOP WITH BASES AROUND 5000
FEET TOMORROW AROUND MIDDAY WITH WINDS THROUGHOUT THE VALID TAF
PERIOD REMAINING OUT OF THE SOUTH.
GOSSELIN
&&
.LSX WATCHES/WARNINGS/ADVISORIES...
MO...NONE.
IL...NONE.
&&
$$
WFO LSX
AREA FORECAST DISCUSSION
NWS GLASGOW MT
241 PM MDT THU JUN 20 2013
.SHORT TERM...FOR NORTHEAST MONTANA...TONIGHT THROUGH SATURDAY...
A FEW THUNDERSTORMS ARE INITIATING OVER SHERIDAN COUNTY THIS
AFTERNOON. CUMULUS DEVELOPMENT IS ALSO TAKING PLACE ACROSS SOME OF
THE WESTERN ZONES AND SO PLACED THE CWA BROADLY INTO SLIGHT CHANCE
POPS. THE LATEST HRRR MODEL RUN SHOWS CONVECTION INITIATION ACROSS
PHILLIPS COUNTY THIS AFTERNOON AND SO HAVE SOMEWHAT HIGHER POPS
THERE. WITH EXCEPTION OF A FEW STORMS...STILL EXPECTING A MUCH
QUIETER EVENING AS COMPARED TO LAST NIGHT.
FRIDAY AND SATURDAY...NEXT UPPER LEVEL SHORTWAVE ROTATES AROUND
UPPER LEVEL LOW. THIS WILL COMBINE WITH AVAILABLE MOISTURE TO
PROVIDE A DECENT CHANCE OF SHOWERS AND THUNDERSTORMS. MODEL
DISAGREEMENT EXISTS THOUGH WITH THE GFS KEEPING THE CWA DRY AND
THE ECMWF SHOWING SOME OF THE BEST POTENTIAL. LEANED WITH THE
ECMWF SOLUTION FOR NOW AS IT SEEMS TO ALSO HAVE SUPPORT FROM THE
LATEST NAM SOLUTION. BEST VERTICAL ASCENT ACROSS NORTHEAST MONTANA
LOOKS TO BE SATURDAY AFTERNOON AND EVENING OUT AHEAD OF THE
SHORTWAVE COINCIDENT WITH THE BEST PVA. NAM BUFKIT SOUNDINGS SHOWS
PRECIPITABLE WATER VALUES GENERALLY BETWEEN A HALF OF AN INCH AND
AN INCH. NOT SEEING MUCH IN TERMS OF CONVECTIVE PARAMETERS HOWEVER
SO WITH ANY CONVECTION THAT INITIATES...STRONG STORMS SHOULD BE
LIMITED. HOWEVER...LOCALLY HEAVY RAINFALL CERTAINLY IS A
POSSIBILITY...ESPECIALLY DUE TO LOW LEVEL SOUTHEASTERLY FLOW
BRINGING IN MOISTURE FROM THE GULF OF MEXICO. MALIAWCO
.LONG TERM...SATURDAY NIGHT THROUGH THURSDAY...
GOING FORECAST LOOKED GOOD TODAY AND ONLY A TWEAK TO A TEMPERATURE
GRID ON TUESDAY NIGHT WAS MADE. JAMBA
PREVIOUS DISCUSSION...
SATURDAY NIGHT...A STRONG SHORTWAVE ON SOUTH SIDE OF UPPER LOW IN
ALBERTA AND SASKATCHEWAN ROTATES THROUGH EASTERN MONTANA. EXPECT
SHOWERS AND THUNDERSTORMS TO OCCUR OVER MOST OF THE AREA AS THIS
WAVE MOVES THROUGH. THE PRECIP COULD LINGER INTO SUNDAY ESPECIALLY
IN THE NORTHEAST HALF OF THE REGION AS THE WAVE MOVES TO THE EAST
AND THE UPPER LOW REMAINS TO THE NORTH. INCREASED POPS FOR
SATURDAY EVENING TO LIKELY/CATEGORICAL AND MAINTAINED LIKELY POPS
IN THE EASTERN HALF AFTER MIDNIGHT SATURDAY NIGHT.
SHORTWAVE RIDGE WILL BRING A BREAK IN THE STORMS SUNDAY NIGHT AND
MONDAY MORNING.
FLOW ALOFT TURNS TO THE SOUTHWEST BY MONDAY AFTERNOON WITH UPPER
LOW OFF THE PACIFIC NORTHWEST COAST. A SHORTWAVE TROUGH IN THE
SOUTHWEST FLOW ALOFT WILL BRING A CHANCE OF THUNDERSTORMS STARTING
MONDAY AFTERNOON AND LASTING INTO TUESDAY EVENING.
A STRONG RIDGE BUILDS OVER THE WESTERN U.S. STARTING ON WEDNESDAY
WITH DRY WEATHER AND WARMING TEMPERATURES. FORRESTER
&&
.AVIATION...
VFR CONDITIONS ARE EXPECTED WITH ISOLATED SHOWER THIS EVENING WEST
AND EAST OF THE TERMINALS. LIGHT WINDS TONIGHT WILL INCREASE
SLIGHTLY FROM THE SOUTHEAST FRIDAY. SHOWERS AND THUNDERSTORMS WILL
BEGIN TO AFFECT MAINLY THE SIDNEY AND GLENDIVE LOCATIONS BY LATE
FRIDAY. JAMBA
&&
.GLASGOW WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
WEATHER.GOV/GLASGOW
AREA FORECAST DISCUSSION
NWS OMAHA/VALLEY NE
304 PM CDT THU JUN 20 2013
.SHORT TERM...TONIGHT THROUGH FRIDAY.
THE PRIMARY FORECAST CONCERNS IN THIS PERIOD ARE STILL THE POTENTIAL
FOR TSTMS AND TEMPERATURES.
UPPER AIR CHARTS FROM THIS MORNING SHOWED THE FOLLOWING. 80 KNOT
WINDS AT 300 MB STRETCHED FROM NORTHERN CALIFORNIA INTO WYOMING. A
LONGWAVE TROUGH WAS OVER THE WESTERN U.S. WITH A WEAK RIDGE OVER THE
PLAINS. 12 HOUR HEIGHT FALLS OF 110 METERS WERE NOTED AT 500 MB OVER
MONTANA. THERMAL RIDGE AT 700 MB EXTENDED FROM MEXICO NORTHWARD INTO
EASTERN COLORADO. THE KOAX 12Z SOUNDING SHOWED A 700 MB TEMP OF 8 C
AND A DEWPOINT OF 4 C. MOIST BAND AT 700 MB EXTENDED FROM WEST
TEXAS UP INTO THE DAKOTAS. THIS MOISTURE WILL BE ONE OF THE THINGS
TO MONITOR IN REGARDS TO CONVECTIVE COVERAGE THE NEXT SEVERAL
DAYS.
SURFACE ANALYSIS EARLY THIS AFTN SHOWED ONE LOW PRESSURE CENTER UP
ALONG THE NORTH DAKOTA/SOUTH DAKOTA BORDER AND ANOTHER IN SOUTHEAST
COLORADO. A COLD FRONT STRETCHED FROM THE LOW OVER THE DAKOTAS DOWN
INTO WESTERN NEBRASKA AND NORTHEAST COLORADO. GUSTY SOUTH WINDS WERE
IN PLACE ACROSS THE FORECAST AREA WITH DEWPOINTS IN THE UPPER 60S
TO AROUND 70.
THIS EVENING...WINDS SHOULD RELAX A LITTLE. THE ATMOSPHERE WILL BE
VERY UNSTABLE...WITH CAPE VALUES IN EXCESS OF 3000 J/KG AND 0-6 KM
SHEAR VALUES OF 20-30 KNOTS. HOWEVER...LIKE YESTERDAY...WE DO NOT
HAVE MUCH OF A FOCUSING MECHANISM FOR STORM DEVELOPMENT. MOST
RECENT HRRR AND 13 KM RAP MODELS SUGGEST SOME STORMS ARE POSSIBLE
ALONG AND EAST OF THE MID LEVEL CAP...AS WELL AS ACROSS PARTS OF
NORTHEAST NEBRASKA. 4 KM WRF-NMM RUN FROM 12Z IS MUCH MORE BULLISH
WITH STORM DEVELOPMENT THIS EVENING FROM THE DAKOTAS/MINNESOTA DOWN
INTO PARTS OF NORTHERN AND WESTERN NEBRASKA. ALTHOUGH THAT IS ONE
POSSIBILITY...TENDED TO SHY AWAY FROM THAT SCENARIO. BOTH THE 12Z
NAM AND GFS ALSO APPEARED TOO WET TONIGHT IN OUR AREA.
FRIDAY...KEPT THUNDERSTORM CHANCES BELOW 15 PERCENT. TEMPERATURES
SHOULD TOP OUT IN THE LOWER OR MID 90S WITH MAX HEAT INDICES UP NEAR
100. WINDS SHOULD INCREASE INTO THE BREEZY OR WINDY CATEGORY AGAIN.
MILLER
.LONG TERM...FRIDAY NIGHT THROUGH THURSDAY.
THE BEST CHANCES FOR THUNDERSTORMS IN THIS PERIOD APPEAR TO BE FROM
SATURDAY NIGHT THROUGH SUNDAY NIGHT. A GENERAL BLEND/CONSENSUS OF
THE 12Z MODELS IS THAT A FRONTAL BOUNDARY SHOULD PUSH INTO OUR AREA
FROM THE NORTHWEST SATURDAY NIGHT...THEN LINGER IN THE AREA SUNDAY
AND SUNDAY NIGHT. INSTABILITY AND SHEAR APPEAR THAT THEY WOULD BE
ADEQUATE FOR SOME ORGANIZED SEVERE WEATHER.
THE TENDENCY FOR A TROUGH AT 500 MB OVER THE WESTERN U.S. SHOULD
CONTINUE INTO EARLY NEXT WEEK. AFTER THAT...A MORE SUMMER-LIKE FLOW
PATTERN IS FORECAST TO DEVELOP DUE TO RETROGRESSION. TROUGH AXIS
WILL SHIFT BACK TO AROUND 140 DEGS WEST LONGITUDE WHILE A 500 MB
RIDGE STRENGTHENS OVER THE DESERT SOUTHWEST AND SOUTHERN ROCKIES.
KEPT A MAINLY DRY FORECAST GOING FOR MONDAY INTO THURSDAY...DUE TO
LOW CONFIDENCE. KEPT HIGHS MAINLY IN THE UPPER 80S TO MID 90S WITH
LOWS IN THE UPPER 60S TO MID 70S.
MILLER
&&
.AVIATION...
18Z TAFS FOR KOFK...KOMA AND KLNK.
CUMULUS FIELD HAS INCREASED AND SHOULD CONTINUE THIS AFTERNOON
WITH SCT-BKN FL040 DUE TO MOIST LOW LEVELS AND TRIGGER
TEMPERATURES IN THE MID 80S. THUNDERSTORM CHANCE CONFIDENCE TOO
LOW TO MENTION AT THIS TIME WITH WARM AIR ALOFT THIS AFTERNOON AND
THIS EVENING AND UNCERTAINTY IN HOW CONVECTION EVOLVES IN THE
DAKOTAS LATER TONIGHT. SOUTHEAST WINDS 15 TO 25KT SUSTAINED WITH
SOME HIGHER GUSTS. TONIGHT...WIND DECREASE AFTER 01-03Z TO 10 TO
15KTS...HOWEVER DO MENTION LLWS AT ALL THREE SITES. INCLUDED SOME
MVFR CIGS AND VSBYS AT KOFK AFTER 11Z AT KOFK...AND WILL NEED TO
MONITOR FOR KOMA AND LNK.
ZAPOTOCNY
&&
.OAX WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
IA...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS NORTH PLATTE NE
120 PM CDT THU JUN 20 2013
.SYNOPSIS...
ISSUED AT 335 AM CDT THU JUN 20 2013
H5 ANALYSIS TONIGHT HAS A LARGE AREA OF LOW PRESSURE EXTENDING
FROM OFF THE COAST OF WASHINGTON STATE...EWD TO SRN IDAHO. A
TROUGH OF LOW PRESSURE EXTENDED SOUTH INTO SRN CALIFORNIA. FURTHER
EAST...A RIDGE OF HIGH PRESSURE EXTENDED FROM THE LOWER MISSOURI
VALLEY NNWD INTO SRN SASKATCHEWAN. A SECOND TROUGH WAS NOTED
ACROSS NEW ENGLAND. AT THE SURFACE...A SURFACE TROUGH OF LOW
PRESSURE WAS NOTED ALONG THE NEBR/WY BORDER SWD INTO EASTERN
COLORADO. A DECENT PRESSURE GRADIENT ACROSS NEBRASKA WAS PRESENT
THIS MORNING...WHICH HAS LED TO MILD READINGS IN THE UPPER 60S AND
LOWER 70S AS OF 3 AM CDT. ACROSS THE EASTERN PANHANDLE...ISOLATED
THUNDERSTORMS HAVE DEVELOPED OVER THE EASTERN PANHANDLE OVER THE
PAST COUPLE OF HRS AND CONTINUES TO LIFT TO THE NORTHEAST INTO
SOUTH DAKOTA.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 335 AM CDT THU JUN 20 2013
MAIN FORECAST CHALLENGE CONTINUES TO BE THUNDERSTORM CHANCES
ACROSS THE HIGH PLAINS AS SOUTHWESTERLY FLOW ALOFT CONTINUES. THE
MODELS...MOST NOTABLY THE NAM SOLN...HAVE STRUGGLED WITH PLACEMENT
OF TSRAS OVERNIGHT TONIGHT. THE HIGH RES RUC HAS BEEN PLAYING
CATCH UP OVER THE PAST COUPLE OF HRS...AND HAS FINALLY CAUGHT ON
TO THE ONGOING CONVECTION OVER THE EASTERN PANHANDLE COUNTIES
ATTM. THIS ACTIVITY IS EXPECTED TO WEAKEN AND DISSIPATE OVER THE
NEXT 2 TO 4 HRS AS THE LOW LEVEL JET WEAKENS AND SHIFTS EAST
TOWARD SUNRISE. IN THE MEANTIME...WILL MONITOR AND MAY NEED TO
INCLUDE POPS ACROSS THE NORTH CENTRAL FOR THIS MORNING THROUGH 15Z
IF ACTIVITY INCREASES IN INTENSITY AND COVERAGE. RIGHT NOW...BASED
ON THE FCST OF THE H85 LOW LEVEL JET...BELIEF IS THAT CONVECTION
WILL END TOWARD SUNRISE. FOR TODAY...SERLY AND EASTERLY WINDS WILL
DEVELOP ACROSS THE AREA AS A FRONTAL BOUNDARY WASHES OUT OVER THE
PANHANDLE. EASTERLY FLOW WILL PUSH 65 TO 70 DEW POINTS WEST...TO A
LINE FROM NORTH PLATTE TO VALENTINE BY 00Z. SB CAPES DEPICTED IN
THE LATEST NAM SOLN ARE RUNNING 4000 TO 5000 J/KG ACROSS
SOUTHWESTERN AND CENTRAL NEBRASKA BY 00Z...WHICH IS MORE THAN
ENOUGH CONVECTIVE POTENTIAL FOR THUNDERSTORMS. THE MAIN UNKNOWN IN
ALL OF THIS THOUGH...IS WHETHER OR NOT THE CAP WILL HOLD THIS
AFTERNOON. IF THE CAP CAN BREAK...PLENTY OF DEEP LAYER SHEAR
EXISTS TO SUPPORT SUPERCELL THUNDERSTORMS. SINCE THE CAP IS
WEAKEST IN THE SOUTHWEST AND CENTRAL...WITH CINS APPROACHING ZERO
BY 00Z FRIDAY...WILL PLACE SOME 20 TO 30 POPS IN THESE AREAS FOR
THIS EVENING. INTO THE OVERNIGHT...A H700 FRONT WILL LIFT NORTH
ACROSS THE FORECAST AREA...STALLING ACROSS THE NORTHERN FORECAST
AREA TOWARD 12Z FRIDAY. AS THIS FEATURE LIFTS NORTH...A NICE H85
LOW LEVEL JET WILL DEVELOP...WITH ENHANCED LIFT AND INCREASED PCPN
CHANCES ACROSS THE NORTH OVERNIGHT TONIGHT. WITH THIS IN
MIND...SHIFTED CHANCE POPS FROM THE SOUTHWEST AND CENTRAL
CWA...NWD INTO NORTH CENTRAL NEBRASKA OVERNIGHT.
.LONG TERM...(FRIDAY THROUGH WEDNESDAY)
ISSUED AT 335 AM CDT THU JUN 20 2013
LARGE UPPER LEVEL LOW PRESSURE SYSTEM WILL SLOWLY MIGRATE EAST INTO
THE NORTHERN ROCKIES FRIDAY EVENING. THIS KEEPS THE UPPER FLOW ALOFT
SOUTHWEST ACROSS OUR AREA...WITH A QUASI-STATIONARY SURFACE FRONT
EXTENDING NORTHEAST TO SOUTHWEST THROUGH THE LOCAL AREA. THE GEM
REGIONAL AND NAM MODELS ARE IN GOOD AGREEMENT...AND HAVE THE FRONT
LATE FRIDAY AFTERNOON ALONG A LINE FROM ONEILL...TO NORTH
PLATTE...TO IMPERIAL. EXTREMELY UNSTABLE CONDITIONS WILL RESIDE
INVOF THE FRONT...WITH BULK SHEAR FAVORABLE FOR SEVERE STORMS ACROSS
NORTHERN NEBRASKA AND SOUTH DAKOTA. INVERSION/CAP WILL PROBABLY KEEP
SFC BASED CONVECTION AT BAY DURING THE DAY ALONG THE FRONT. FARTHER
WEST NEAR THE BLACK HILLS AND PORTIONS OF NORTHWEST NEBRASKA TO THE
NORTH OF THE FRONT...MOIST POST FRONTAL EASTERLY UPSLOPE FLOW SHOULD
RESULT IN TSTM DEVELOPMENT BY LATE AFTERNOON. SHEAR WILL SUPPORT
SUPERCELLS WITH THIS INITIAL DEVELOPMENT. DURING THE EVENING A VERY
HEALTHY SOUTHERLY LLJ WILL NOSE NORTHWARD FROM KS INTO THE
STATIONARY FRONT LYING THROUGH THE AREA...WITH ELEVATED STORMS
LIKELY TO DEVELOP JUST TO THE NORTH OF THE FRONT ACROSS THE
SANDHILLS AND NORTH CENTRAL NEBRASKA. SOME OF THESE WILL LIKELY BE
SUPERCELLS CAPABLE OF LARGE HAIL. THE EARLIER MENTIONED CONVECTION
THAT DEVELOPS ACROSS THE BLACK HILLS/NORTHWEST NEBRASKA REGION
SHOULD CONGEAL INTO AN EASTWARD MOVING MCS...AND RIDE JUST NORTH OF
THE FRONT ACROSS NORTHERN NEBRASKA AND SOUTHERN SOUTH DAKOTA. ALL IN
ALL IT APPEARS IT COULD BE A STORMY NIGHT...WITH DEVELOPMENT OF
STORMS DURING THE EVENING ACROSS NORTHERN NEBRASKA AS THE LLJ
INCREASES...FOLLOWED BY THE EASTWARD MOVING MCS ROLLING OFF THE HIGH
PLAINS.
SATURDAY LOOKS SIMILAR TO FRIDAY...WITH THE STATIONARY FRONT
REMAINING ACROSS THE AREA. NAM IS QUITE SIMILAR TO FRIDAY
AFTERNOON WITH THE FRONTAL LOCATION...ROUGHLY ALONG AN
ONEILL...TO NORTH PLATTE...TO IMPERIAL LINE. THIS IS IN QUESTION
HOWEVER...AS THE EXPECTED MCS/CONVECTION FROM FRIDAY NIGHT WILL
LIKELY PLAY A ROLE IN WHERE FRONT ENDS UP. THE FRONT COULD END UP
FARTHER SOUTH DURING THE MORNING SATURDAY...PERHAPS DOWN INTO
NORTHERN KS. EVEN IF THIS WERE TO OCCUR...THE FRONT WOULD LIKELY
LIFT BACK TO THE NORTH AS A WARM FRONT SATURDAY AFTERNOON. JUST
NOT CERTAIN WHERE THE FINAL RESTING PLACE WILL BE BY LATE SATURDAY
AFTERNOON WHEN SFC BASED CONVECTION COULD TRY TO FIRE ALONG THE
FRONT. THE MORE LIKELY SCENARIO WOULD BE FOR ELEVATED STORMS TO
DEVELOP TO THE NORTH OF THE FRONT SATURDAY EVENING/OVERNIGHT
ACROSS NORTHERN NEBRASKA AND SOUTH DAKOTA. SIMILAR TO FRIDAY
NIGHT...SOME OF THE STORMS COULD BE SEVERE.
IT APPEARS BY SUNDAY THAT THE LARGE UPPER LEVEL LOW WHICH HAS
BEEN ANCHORED IN THE PACIFIC NORTHWEST...WILL MOVE EAST/NORTHEAST
INTO SOUTHERN CANADA. THIS SHOULD HELP FINALLY DRIVE THE
STATIONARY FRONT SOUTH INTO KANSAS. THIS WILL BE SHORT LIVED
HOWEVER...AS THE ECMWF ADVERTISES THE FRONT RETURNING NORTH THROUGH
THE AREA SUNDAY NIGHT INTO MONDAY AS A WARM FRONT. SOME SCATTERED
TSTMS ARE POSSIBLE AS THE FRONT RETURNS NORTH SUNDAY NIGHT AND
MONDAY MORNING. THIS MAY BE THE LAST OF THE BETTER PRECIPITATION
CHANCES FOR AWHILE...AS BOTH THE GFS AND ECMWF BUILD AN EXPANSIVE
RIDGE OF HIGH PRESSURE. THERE ARE SOME DIFFERENCES WITH THE
PLACEMENT OF THE RIDGE...WITH THE THE ECMWF ACROSS THE WESTERN
CONUS WITH THE CENTER...AND THE GFS ACROSS THE SOUTHERN PLAINS.
SLIGHT CHANCES FOR STORMS ARE POSSIBLE IN BOTH MODEL SOLUTIONS...IN
A RING OF FIRE TYPE SCENARIO. WILL WAIT TO ADD ANY CHANCES AT THIS
POINT HOWEVER...AND SEE IF MODELS COME INTO BETTER AGREEMENT WITH
THE CENTER OF THE RIDGE.
TEMPERATURE WISE...IT LOOKS PRETTY WARM WITH THE RIDGE BUILDING TO
OUR SOUTH AND WEST. THE HOTTEST TEMPERATURES THE NEXT SEVERAL DAYS
WILL BE ACROSS WEST AND SOUTHWEST NEBRASKA...WHERE DAILY HIGHS IN
THE 90S ARE ANTICIPATED. CONDITIONS A LITTLE COOLER FARTHER NORTH
AND EAST...BUT HIGHS WILL STILL FLIRT WITH 90 DEGREES FROM TIME TO
TIME.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z FRIDAY AFTERNOON)
ISSUED AT 115 PM CDT THU JUN 20 2013
LOW/MID LEVEL STRATUS CONTINUES OVER MUCH OF THE AREA THIS
AFTERNOON...HOWEVER IT CONTINUES TO ERODE FROM THE WEST AS A COLD
FRONT SLOWLY PUSHES EAST. THE CLOUDS AREA ALSO ERODING FROM THE
SOUTH AS SUNNY SKIES AND TEMPS IN THE 80S HELP TO MIX THE LOWER
LEVELS. THE CIGS WITH THE STRATUS HAVE GENERALLY LIFTED TO BKN030
TO BKN050 AND WILL CONTINUE TO SLOWLY LIFT THROUGHOUT THE
AFTERNOON.
LATER THIS AFTERNOON THUNDERSTORMS ARE POSSIBLE ACROSS THE REGION.
STILL SOME UNCERTAINTY ON HOW MUCH COVERAGE AND IF THE CAP WILL BE
BROKEN. THUS WITH LOW CONFIDENCE ON IMPACT AT THE TERMINALS...NO
MENTION OF THUNDER YET. WATCH FOR UPDATES WHEN/IF CONVECTION DOES
DEVELOP.
TOMORROW MORNING EXPECT THE STRATUS TO REDEVELOP WITH ALL THE
RESIDUAL LOW LEVEL MOISTURE ESPECIALLY EAST OF THE STALLING COLD
FRONT.
&&
.LBF WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...CLB
SHORT TERM...CLB
LONG TERM...TAYLOR
AVIATION...MASEK
AREA FORECAST DISCUSSION
NWS HASTINGS NE
1232 AM CDT THU JUN 20 2013
.UPDATE...
ISSUED AT 1050 PM CDT WED JUN 19 2013
WE ARE NOTING AN INCREASE IN CONVECTIVE ACTIVITY IN IR SATELLITE
OVER THE LAST 40 MINS...PRIMARILY ALONG THE ERN WY BORDER AND OVER
THE DAKOTAS. THE NCAR WRF-ARW WITH GFS BOUNDARY CONDITIONS SEEMS
TO HAVE A GOOD DEPICTION OF THIS DEVELOPMENT. IT SUGGESTS A N-S
ORIENTED AXIS OF TSTMS WILL DEVELOP OVER ERN KS/NEB. 21Z SREF
PROBABILITIES FOR .01 QPF HAVE THIS N-S AXIS JUST E OF HWY 281.
THE 00Z LBF SOUNDING SHOWS ABOUT -58 J/KG OF CINH FOR A SFC-BASED
PARCEL...AND PROBABLY A LITTLE MORE FOR A PARCEL LIFTED FROM 750
MB. OAX WAS UNCAPPED. ALL REGIONAL SOUNDINGS SUGGEST 1300-2000
J/KG OF MUCAPE. SO THERE WILL BE POTENTIAL FOR SEVERE HAIL IF
TSTMS DEVELOP.
WILL CONTINUE TO MONITOR.
&&
.SHORT TERM...(THIS EVENING THROUGH THURSDAY)
ISSUED AT 430 PM CDT WED JUN 19 2013
MORE LOW-CONFIDENCE THUNDERSTORM CHANCES ARE THE MAIN CONCERN
ESPECIALLY FOR LATE TONIGHT...WITH REASONABLE CONFIDENCE THAT
THE THURSDAY DAYTIME HOURS SHOULD HOLD STORM-FREE UNDER A
STRENGTHENING CAP. OTHERWISE...HEAT/HUMIDITY THURSDAY IS EXPECTED
TO RISE ANOTHER NOTCH ABOVE THAT OF TODAY AS A GRADUAL WARMING
TREND CONTINUES.
20Z SURFACE ANALYSIS HIGHLIGHTS A DEEPENING 996 MILLIBAR LOW OVER
CENTRAL WY...WHICH HAS TIGHTENED THE CENTRAL PLAINS PRESSURE
GRADIENT THUS RESULTING IN SUSTAINED SOUTH-SOUTHEAST WINDS 15-25
MPH THIS AFTERNOON GUSTING 30-35 MPH IN SPOTS. THIS SURFACE LOW
HAS DEEPENED IN RESPONSE TO A FAIRLY VIGOROUS...NEGATIVELY TILTED
SHORTWAVE TROUGH BARRELING NORTHEAST ACROSS SOUTHERN ID...ALONG
THE SOUTHEAST PERIPHERY OF AN EXPANSIVE CLOSED MID LEVEL LOW
ANCHORED OVER THE PACIFIC NORTHWEST. CLOSER TO HOME...WATER VAPOR
IMAGERY AND SHORT TERM MODEL DATA DEPICT MODEST QUASI-ZONAL
FLOW...WITH THE MAIN SUBTLE SHORTWAVE TROUGH CURRENTLY EXITING THE
CWA EASTWARD...WITH MID LEVEL DRYING NOTED IN ITS WAKE. JUST
WITHIN THE PAST HOUR...A FEW SHOWERS/THUNDERSTORMS HAVE FLARED UP
JUST EAST OF OUR CWA IN EASTERN NEB...IN CLOSER PROXIMITY TO THIS
ADVANCING WAVE AND IN THE PRESENCE OF A WEAKLY CAPPED AIRMASS
FEATURING 1500+ J/KG 0-1KM MLCAPE. ACROSS OUR AREA HOWEVER...AT
LEAST UP THROUGH NOW...ITS BEEN A RAIN/THUNDER-FREE DAY...UNDER
ONLY A FAIR WEATHER CUMULUS FIELD MOST AREAS...AND A BIT MORE MID-
LEVEL CLOUD DEVELOPMENT IN THE FAR WEST WITHIN A ZONE OF THETA-E
ADVECTION EVIDENT AT 700MB. UNLIKE YESTERDAY AT THIS TIME...THERE
IS NO SURFACE FRONT/OUTFLOW BOUNDARY AND NO EVIDENT SUBTLE
INCOMING SHORTWAVE TO KICK OFF CONVECTION...AND IT GOES WITHOUT
SAYING THAT SEVERAL DETERMINISTIC MODEL QPF FIELDS ENDED UP BEING
CONSIDERABLY OVERDONE ON RAIN POTENTIAL TODAY. TEMP-WISE...MOST
AREAS ARE HEADED FOR HIGHS BETWEEN 86-91.
LOOKING AHEAD THROUGH LATE THIS AFTERNOON INTO TONIGHT...THE BIG
PICTURE ALOFT INVOLVES A NORTHWARD BUILDING OF A SOUTH CENTRAL
CONUS RIDGE INTO THE CENTRAL PLAINS...WHILE THE STRONG SHORTWAVE
TROUGH WELL TO THE NORTHWEST SLIDES UP ACROSS MT. MEANWHILE OVER
THE LOCAL AREA...FLOW WILL REMAIN QUASI-ZONAL AS AT LEAST 1-2 MORE
VERY SUBTLE DISTURBANCES POSSIBLY PASS EASTWARD ACROSS THE REGION.
OF NOTE...PRONOUNCED WEST-EAST MID LEVEL WARM-AIR ADVECTION OF AN
ELEVATED MIXED LAYER WILL OCCUR TONIGHT...WITH 700MB TEMPS BY
SUNRISE PROGGED TO RANGE FROM AROUND 10C IN THE EASTERN CWA TO
AROUND 15C IN THE WEST. AT THE SURFACE...A NORTH-SOUTH TROUGH AXIS
WILL ADVANCE EASTWARD INTO WESTERN NEB/FAR WESTERN KS
TONIGHT...BUT OUT AHEAD OF THIS FEATURE THE CWA WILL CONTINUE TO
EXPERIENCE STEADY SOUTH-SOUTHEAST BREEZES GENERALLY SUSTAINED 15+
MPH WITH SOME HIGHER GUSTS. THIS SHOULD HELP RESULT IN SLIGHTLY
MILDER LOW TEMPS VERSUS LATELY...AND NUDGED PREVIOUS VALUES UP
SLIGHTLY WITH MOST AREAS BOTTOMING OUT 65-69. STARTING TO SOUND
LIKE A BROKEN RECORD...BUT WITH MODELS CONTINUING TO STRUGGLE
MIGHTILY WITH CONVECTIVE TRENDS...CONFIDENCE IS BELOW AVERAGE. THE
BOTTOM LINE IS THAT THERE IS ONLY A 20 PERCENT CHANCE OF
SHOWERS/STORMS CWA-WIDE THROUGH 01Z/8PM...AND THEN AGAIN AFTER
MIDNIGHT. THE PRE-8PM POTENTIAL WOULD STEM FROM ANY DIURNALLY-
DRIVEN CONVECTION THAT WOULD MOST LIKELY FLIRT WITH FAR EASTERN
COUNTIES...AND ANY HIGHER-BASED MID LEVEL CONVECTION THAT MIGHT
SKIRT THE WEST. ALTHOUGH THE LIKELIHOOD OF VIGOROUS DEVELOPMENT IS
QUITE LOW GIVEN LACK OF FORCING/LOW LEVEL FOCUS...CANNOT
COMPLETELY RULE OUT A ROGUE STRONG/SEVERE STORM. BY SUNSET...HAVE
DECENT CONFIDENCE IN A DRY PERIOD LOCALLY LASTING SEVERAL
HOURS...BEFORE THE NEXT QUESTION BECOMES...DOES ANYTHING THAT
DEVELOPS OUT WEST THIS EVENING SURVIVE EASTWARD INTO THE CWA...OR
DOES NEW DEVELOPMENT OCCUR ON THE EDGE OF THE MID-LEVEL CAP AND
WITHIN THE AXIS OF A FAIRLY STOUT 50+ KT LOW LEVEL JET. ALTHOUGH
AM ONLY KEEPING POPS AT 20 PERCENT...IT WOULD SEEM THIS LATE NIGHT
STORM POTENTIAL COULD BE A BIT MORE LIKELY/WIDESPREAD THAN LATE
THIS AFTERNOON/EARLY EVENING...WITH MODELS SUCH AS THE RAP FIRING
UP A DECENT AREA OF OVERNIGHT STORMS ESPECIALLY IN CENTRAL/EASTERN
COUNTIES. SHOULD THESE STORMS ACTUALLY DEVELOP...CERTAINLY CAN/T
DISCOUNT A THREAT FOR SEVERE HAIL WITH THE NAM DEPICTING 2000+ J/KG
MUCAPE TO PARCELS BETWEEN 850-700MB. COULD BE AN INTERESTING FEW
HOURS LATE TONIGHT IF IN FACT SOMETHING HAPPENS TO FIRE.
TURNING TO THE THURSDAY DAYTIME PERIOD...OPTED TO HOLD THE COURSE
FROM PREVIOUS FORECAST AND KEEP OUT ANY SHOWER/STORM MENTION FROM
12Z-00Z/7AM-7PM. ALOFT...AT LEAST SMALL MID LEVEL HEIGHT-RISES
WILL CONTINUE AS THE RIDGE BUILDS INTO THE CENTRAL CONUS FROM THE
SOUTHWEST...WHILE VERY WARM MID LEVEL 700MB TEMPS OF GENERALLY
13-15C OVERSPREAD THE ENTIRE CWA BY MID-AFTERNOON. AT THE
SURFACE...THE AFOREMENTIONED TROUGH AXIS WILL STALL OUT FROM NORTH
CENTRAL TO SOUTHWEST NEB DURING THE AFTERNOON...WHICH WILL ALLOW FOR
RELAXING BREEZES ACROSS OUR FAR WESTERN COUNTIES...WHILE THE
MAJORITY OF THE CWA CONTINUES TO EXPERIENCE SOUTHERLY SUSTAINED
SPEEDS 15-20 MPH. WITH WARMER TEMPS MOVING IN ALOFT...DECENT
MIXING...AND AT LEAST A FAIR AMOUNT OF SUNSHINE ESPECIALLY ONCE
ANY POSSIBLE MORNING STRATUS BURNS OFF/LIFTS AWAY...WILL AIM FOR
HIGHS RANGING FROM NEAR 90 NORTHEAST TO UPPER 90S
SOUTHWEST...WHICH COMBINED WITH DEWPOINTS AVERAGING MID-UPPER 60S
WILL YIELD HEAT INDEX VALUES GENERALLY 92-98 AT MID-AFTERNOON.
THERE ARE TWO CAVEATS THAT COULD MESS UP THE DRY FORECAST. FIRST
OFF...THERE IS A CHANCE THAT ANY LATE NIGHT/PRE-DAWN CONVECTION
MAY NOT QUITE CLEAR OUR EASTERN COUNTIES BY 7AM IF IT FIRES
UP...BUT GIVEN UNCERTAINTY IN DEVELOPMENT IN THE FIRST PLACE WILL
DEFER TO NEXT SHIFT TO TAKE A CLOSER LOOK AT THE POSSIBILITY OF
SOME MORNING POPS MAINLY WITHIN THE EASTERN 1/4 OF THE CWA.
AGAIN...CAN/T RULE OUT SOME SEVERE-CRITERIA HAIL IF THIS UNFOLDS.
ONCE THIS POTENTIAL MORNING CONVECTION VACATES...THE VAST MAJORITY
OF THE DAY SHOULD BE STRONGLY CAPPED...AND THINK IT SHOULD HOLD
THROUGH AT LEAST 7PM...DESPITE THE NAM ADVERTISING A VOLATILE LATE
AFTERNOON ENVIRONMENT WITH 4000+ J/KG MLCAPE AND WEAK TO MODEST
25KT OF DEEP-LAYER SHEAR. REFLECTIVITY PROG FROM THE 12Z 4KM WRF-
NMM CLEARLY KEEPS CONVECTION AT BAY LOCALLY...ALTHOUGH THE ECMWF
DOES SUGGEST OUR FAR WESTERN COUNTIES COULD COME SOMEWHAT CLOSE TO
ANYTHING THAT HAPPENS TO BREACH THE CAP ALONG THE TROUGH AXIS
LYING NEAR THE CWA...BUT AGAIN THIS SEEMS AN UNLIKELY SCENARIO AND
THUS THE LACK OF STORM MENTION AT THIS TIME.
.LONG TERM...(THURSDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 430 PM CDT WED JUN 19 2013
MAIN FORECAST CONCERNS WILL BE CHANCES FOR THUNDERSTORMS AND
TEMPERATURES.
MODELS ARE FAIRLY SIMILAR IN THE MAIN FEATURES THROUGH THE PERIOD.
AN UPPER LEVEL LOW MOVES OUT OF THE NORTHERN ROCKIES AND INTO THE
CANADIAN PLAINS THURSDAY NIGHT THROUGH THE WEEKEND AND INTO EARLY
NEXT WEEK...THEN AN UPPER LEVEL RIDGE BUILDS OVER THE AREA. FOR
THURSDAY NIGHT THROUGH SATURDAY THERE IS A SURFACE WARM FRONT DRAPED
THROUGH CENTRAL NEBRASKA. MODELS HAVE SOME SLIGHT DIFFERENCES IN THE
LOCATION OF THE FRONT...BUT GENERALLY OVER THE FAR NORTHERN PART OF
THE FORECAST AREA. AS AN UPPER LEVEL WAVE MOVES INTO THE AREA MODELS
BRING IN SOME QPF ALONG THE FRONT THURSDAY NIGHT. THE CONCERN
IS THAT THE 700MB TEMPERATURES ARE AT OR ABOVE 12 DEG C DURING THIS
PERIOD. WITH THE FRONT IN THE AREA THERE IS SOME POTENTIAL THAT A
THUNDERSTORM MIGHT BREAK THROUGH...BUT REALLY BELIEVE THAT WE WILL
BE TOO CAPPED TO GET ANYTHING GOING. ON THE OFF CHANCE THAT THERE IS
A THUNDERSTORM IT HAS THE POTENTIAL TO BE SEVERE. THE MUCAPE IN THE
NORTH DURING THE EVENING IS AROUND 4500 J/KG. DURING THE DAYTIME
BOTH FRIDAY AND SATURDAY HAVE MAINTAINED SOME SLIGHT CHANCE FOR
THUNDERSTORMS IN THE SOUTHWEST. THIS WOULD BE MAINLY DURING THE
AFTERNOON. EVEN THOUGH TEMPERATURES ARE EXPECTED TO BE QUITE WARM
THAT AREA SEEMS PRONE TO SOME ISOLATED THUNDERSTORMS DURING THE HEAT
OF THE DAY.
SATURDAY NIGHT THROUGH SUNDAY NIGHT THE SURFACE LOW MOVES TOWARD THE
EAST AND MAINLY STALLS ACROSS THE AREA BY SUNDAY AFTERNOON. WITH A
COUPLE OF UPPER LEVEL WAVES THAT MOVE INTO THE AREA THERE COULD BE
SOME THUNDERSTORMS ALONG THE FRONT. THE BEST CHANCES WOULD BE DURING
THE NIGHT TIME HOURS.
THE UPPER LEVEL PATTERN CHANGES LATE IN THE PERIOD AS AN UPPER LEVEL
RIDGE BUILDS ACROSS THE AREA. THE FEW UPPER LEVEL WAVES THAT MOVE
ACROSS IT TEND TO BE FURTHER TO THE NORTH. EVEN IF THE SURFACE LOW
IS TO THE WEST THERE ARE NOT MANY THUNDERSTORMS THAT TAKE OFF ON THE
HIGH PLAINS. THEREFORE HAVE KEPT THE FORECAST DRY FOR MONDAY THROUGH
WEDNESDAY.
TEMPERATURES THROUGH THE PERIOD WILL REMAIN ON THE WARM SIDE. EARLY
IN THE PERIOD THE WARM FRONT IS THROUGH THE AREA AND EVEN THE
SURFACE LOW AS IT MOVES TO THE EAST DOES NOT BRING MUCH IN THE WAY
OF COOLER TEMPERATURES. TEMPERATURES ARE EXPECTED TO BE QUITE A BIT
ABOVE NORMAL.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z THURSDAY NIGHT)
ISSUED AT 1232 AM CDT THU JUN 20 2013
REST OF TNGT: VFR SHOULD DECAY TO MVFR CIGS AFTER 09Z...BUT THIS
IS BELOW AVERAGE CONFIDENCE. WE DID SEE SOME 2500 FT CIGS IN NRN
OK LAST HR AND STRONG S WINDS WILL BE TRANSPORTING HIGHER MSTR NWD
WITHIN A BROAD REGION OF LOW-LEVEL ASCENT. SSE WINDS WILL CONTINUE
TO OCCASIONALLY GUST TO AROUND 20 KTS. LLWS WILL DEVELOP...
ESPECIALLY DURING PERIODS OF DECREASED SFC GUSTINESS. THERE IS A
LOW PROBABILITY FOR AN IFR TSTM BUT CONFIDENCE IS NOT HIGH ENUF TO
INCLUDE ATTM.
THU: IT ALL DEPENDS ON IF TSTMS DEVELOP BEFORE DAWN. IF NOT THEN
MVFR CIGS GRADUALLY LIFT AND BECOME SCT AROUND 4K FT. SSE WINDS
WILL GUST 24-28 KTS.
THU THRU 06Z: VFR. LLWS REDEVELOPS...ESPECIALLY DURING PERIODS OF
NO GUSTINESS AT THE SFC.
CIG CONFIDENCE: LOW THRU 18Z THEN AVERAGE
VSBY CONFIDENCE: HIGH EXCEPT IN ANY TSTMS THAN MIGHT DEVELOP
WIND CONFIDENCE: HIGH
WX CONFIDENCE: AVERAGE
&&
.GID WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
KS...NONE.
&&
$$
UPDATE...HALBLAUB
SHORT TERM...PFANNKUCH
LONG TERM...JCB
AVIATION...HALBLAUB
AREA FORECAST DISCUSSION
NWS ALBUQUERQUE NM
328 PM MDT THU JUN 20 2013
.DISCUSSION...
SATELLITE AND SURFACE MOISTURE ANALYSIS SHOW THE MOIST AXIS FOCUSED
FROM NORTHERN MEXICO ACROSS SE NEW MEXICO INTO WEST TX. THE LATEST
RADAR TRENDS INDICATE SHOWER AND STORM COVERAGE INCREASING IN THIS
AREA...WHICH COINCIDES WELL WITH THE 17Z HRRR AND RIDGE OF HIGHEST
THETA-E VALUES FROM THE NAM AND GFS. FARTHER WEST THE FOCUS FOR DRY
AND BREEZY CONDITIONS COINCIDES WITH A MID/UPPER LEVEL DRY SLOT
STRETCHING FROM THE BAJA INTO NORTH CENTRAL NM.
THE DEFINITION OF PERSISTENCE WILL HOLD VERY TRUE ACROSS OUR AREA AS
THERE WILL BE VERY LITTLE CHANGE TO THE PATTERN CONFIGURATION THRU
TUESDAY OF NEXT WEEK. EXPECT VERY DRY...BREEZY...AND HOT CONDITIONS
FOR CENTRAL AND WESTERN NM WITH A FEW STORMS FOCUSED OVER THE SE AND
EAST CENTRAL PLAINS. MAX AND MIN TEMPS WILL BE NEARLY THE SAME EVERY
PERIOD AND ABOVE NORMAL HOWEVER NO RECORDS ARE EXPECTED.
UNFORTUNATELY...EVEN HOTTER CONDITIONS BUT WITH LESS WIND WILL OCCUR
FOR THE WEDNESDAY THRU SATURDAY PERIOD OF NEXT WEEK. THIS MAY BE THE
PEAK FOR THE SUMMER WITH A 596 TO 599DM H5 RIDGE CENTERED DIRECTLY
OVER NORTHERN NM AND SOUTHERN CO. THE ECMWF AND GFS THEN SHOW THE
RIDGE WOBBLING WESTWARD INTO NORTHERN AZ ALLOWING A MOIST BACK DOOR
FRONT TO SLIDE INTO THE EAST. THIS WOULD PROVIDE FOR ANOTHER UPTICK
IN STORM COVERAGE HOWEVER CONFIDENCE ON THIS PATTERN IS VERY LOW AS
CONSISTENCY IS POOR FROM MODEL RUN TO RUN.
GUYER
&&
.FIRE WEATHER...
DRY LINE HAS BEEN DRIVEN BACK TO A LINE FROM JUST EAST OF TUCUMCARI
TO NEAR OR JUST W OF DUNKEN...PRETTY MAJOR EROSION CONSIDERING HOW
FAR WEST IT GOT EARLY THIS MORNING. SHOULD WAFT BACK W TONIGHT...BUT
NOT QUITE AS FAR W AS EARLY TODAY. POOR RH RECOVERIES TONIGHT WEST
OF DRY LINE...BASICALLY W OF A RATON TO RUIDOSO LINE. GOOD TO
EXCELLENT RECOVERIES TO E OF THE DRY LINE. SOME SHOWERS AND STORMS
OF WET VARIETY INTO THE EVE NEAR TO E OF TUCUMCARI TO RUIDOSO LINE.
RED FLAG CONDITIONS OF THIS AFTN SHOULD DROP OUT BETWEEN 7 AND 9 PM.
AT LEAST THRU NEXT TUE LOOKING FOR CURRENT PATTERN TO NOT CHANGE
MUCH...GENERALLY A PATTERN OF A FEW TO SCT SHOWERS AND
STORMS...MOSTLY WET...GENERALLY NEAR AND EAST OF A TUCUMCARI TO
RUIDOSO LINE. MAY ON A COUPLE OF OCCASIONS SEE THAT LINE SHIFT UP TO
75 OR 100 MILES FARTHER E OR W DURING THIS PERIOD. SET UP WILL BE A
PACIFIC NW TROUGH AND AN UPPER HIGH GENERALLY CENTERED BETWEEN
CENTRAL TX AND FAR N MEXICO. VERY DRY AIR WILL KEEP COMING ACROSS NW
HALF TO TWO THIRDS OF NM AROUND THE HIGH...RESULTING IN EXTREMELY
LOW RH MINIMUMS AND MANY HOURS OF SINGLE DIGIT HUMIDITIES TO
CONTINUE AS WELL FROM THE CENTRAL MTN CHAIN WEST TO THE AZ BORDER.
THOUGH DRY THE AIRMASS WILL BE UNSTABLE WITH DAYTIME HEATING AND
ABOVE NORMAL TEMPERATURES. HAINES VALUES OF 6 AND EVEN SOME
LOCALIZED SUPER HAINES WILL SHOW UP LATE IN THE DAY FOR AT LEAST THE
NEXT 3 TO 4 DAYS.
AS FOR HIGHLIGHTS...AM CONTINUING THE RED FLAG WARNING INTO THIS EVE
AS BEFORE...AS MORE AREAS THAN NOT ARE VERY NEAR OR A LITTLE OVER
CRITICAL THRESHOLDS. UPGRADED EXISTING WATCH FOR FRI TO RED FLAG
WARNING AND ADDED FIRE ZONE 104...MAINLY WEST AND CENTRAL
PORTIONS...LARGELY BASED ON HOW FAR E DRYLINE PROGRESSED TODAY. SEE
NO REASON FOR IT NOT TO GET AT LEAST AS FAR E AS CLAYTON FRI
AFTN...MAIN REASON THAT ZONE ADDED. STILL BELIEVE MOST OF LOWER
TERRAIN OF 101 WILL BE MARGINAL AT MOST FOR CRITICAL CONDITIONS FRI
AFTN...BUT HIGHER TERRAIN THERE SHOULD DO BETTER AND WITH DEGREE OF
DRYNESS AND HEAT FELT IT BEST TO UPGRADE THAT ZONE ALONG WITH THE
REST. ALSO HOISTED FIRE WX WATCH FOR SAT AFTN AND EARLY EVE FOR 102
THROUGH 104...107 AND WESTERN PART OF 108.
43
&&
.AVIATION...
18Z TAF CYCLE
VFR CONDITIONS TO CONTINUE THROUGH THE TAF PERIOD WITH A FEW
EXCEPTIONS. ONE BEING RELATIVELY BRIEF MVFR CIGS/VSBYS POSSIBLE
IN AND NEAR SHRA AND TSRA THIS AFTN AND EVE SE OF A LINE FROM
ROUGHLY DES MOINES TO RUIDOSO...MAINLY IMPACTING TAF SITES TCC
AND ROW. MVFR AND PERHAPS EVEN VERY LOCALIZED IFR VSBYS DUE TO
BLOWING DUST ALSO POSSIBLE WITH STRONGEST STORM OUTFLOWS...AGAIN
WITH TCC AND ROW HAVING THE GREATEST CHANCES. MODERATE AND GUSTY
SW LOW LEVEL WIND FLOW TO BE THE RULE ACROSS CENTRAL AND WESTERN
PORTIONS OF THE FORECAST AREA THIS AND FRI AFTN AND EVE. EXPECT AS
STRONG AND AT TIMES EVEN STRONGER SOUTHERLY LOW LEVEL FLOW ACROSS
MUCH OF THE EASTERN PLAINS WITH SURFACE WIND GUSTS TO AROUND 30 OR
35KTS.
43
&&
.PRELIMINARY POINT TEMPS/POPS...
FARMINGTON...................... 51 94 52 93 / 0 0 0 0
DULCE........................... 38 88 39 87 / 0 0 0 0
CUBA............................ 47 90 47 89 / 0 0 0 0
GALLUP.......................... 44 91 45 90 / 0 0 0 0
EL MORRO........................ 40 86 40 87 / 0 0 0 0
GRANTS.......................... 47 91 49 90 / 0 0 0 0
QUEMADO......................... 51 90 51 88 / 0 0 0 0
GLENWOOD........................ 49 96 50 94 / 0 0 0 0
CHAMA........................... 44 80 45 78 / 0 0 0 0
LOS ALAMOS...................... 59 88 58 86 / 0 0 0 0
PECOS........................... 57 87 57 84 / 5 10 5 5
CERRO/QUESTA.................... 51 80 51 79 / 0 0 0 0
RED RIVER....................... 46 74 45 73 / 0 5 0 5
ANGEL FIRE...................... 37 79 36 78 / 0 5 0 5
TAOS............................ 48 86 47 85 / 0 0 0 0
MORA............................ 52 83 53 82 / 5 10 5 5
ESPANOLA........................ 56 91 55 92 / 0 0 0 0
SANTA FE........................ 58 87 58 87 / 0 0 0 0
SANTA FE AIRPORT................ 56 93 56 92 / 0 0 0 0
ALBUQUERQUE FOOTHILLS........... 67 94 67 94 / 0 0 0 0
ALBUQUERQUE HEIGHTS............. 65 97 65 97 / 0 0 0 0
ALBUQUERQUE VALLEY.............. 64 99 64 99 / 0 0 0 0
ALBUQUERQUE WEST MESA........... 61 97 62 97 / 0 0 0 0
LOS LUNAS....................... 61 97 62 96 / 0 0 0 0
RIO RANCHO...................... 60 98 61 98 / 0 0 0 0
SOCORRO......................... 62 100 63 101 / 0 5 0 5
SANDIA PARK/CEDAR CREST......... 57 86 58 86 / 5 5 5 5
TIJERAS......................... 59 92 59 91 / 0 0 0 0
MORIARTY/ESTANCIA............... 56 94 56 92 / 5 5 5 5
CLINES CORNERS.................. 56 88 57 88 / 5 10 5 5
GRAN QUIVIRA.................... 59 89 60 89 / 5 10 5 5
CARRIZOZO....................... 62 92 63 92 / 5 10 10 10
RUIDOSO......................... 56 82 58 84 / 20 20 20 20
CAPULIN......................... 56 86 56 87 / 5 10 5 10
RATON........................... 54 90 54 90 / 5 5 5 5
SPRINGER........................ 54 92 53 91 / 5 10 5 5
LAS VEGAS....................... 54 88 54 89 / 5 10 5 5
CLAYTON......................... 64 95 64 94 / 10 10 10 10
ROY............................. 60 91 59 91 / 5 10 10 10
CONCHAS......................... 66 97 66 97 / 5 10 10 10
SANTA ROSA...................... 66 96 66 97 / 10 10 10 10
TUCUMCARI....................... 69 99 69 100 / 20 20 20 20
CLOVIS.......................... 63 91 63 92 / 30 30 20 20
PORTALES........................ 65 92 64 93 / 30 30 20 20
FORT SUMNER..................... 67 95 67 96 / 10 20 20 20
ROSWELL......................... 68 98 68 100 / 30 30 20 20
PICACHO......................... 62 92 63 94 / 20 20 20 20
ELK............................. 59 86 61 89 / 30 30 30 20
&&
.ABQ WATCHES/WARNINGS/ADVISORIES...
RED FLAG WARNING UNTIL 8 PM MDT THIS EVENING FOR THE FOLLOWING
ZONES...NMZ101>103-105>107-109.
FIRE WEATHER WATCH FROM SATURDAY AFTERNOON THROUGH SATURDAY EVENING
FOR THE FOLLOWING ZONES...NMZ102>104-107-108.
RED FLAG WARNING FROM 1 PM TO 8 PM MDT FRIDAY FOR THE FOLLOWING
ZONES...NMZ101>105.
&&
$$
AREA FORECAST DISCUSSION
NWS BURLINGTON VT
1038 PM EDT FRI JUN 21 2013
.SYNOPSIS...
HIGH PRESSURE ANCHORED OFF THE ATLANTIC COAST WILL KEEP THE NORTH
COUNTRY DRY TODAY WITH PARTLY TO MOSTLY SUNNY SKIES THIS AFTERNOON
AND TEMPERATURES IN THE MID 70S TO LOWER 80S. A WARM FRONT WILL
MOVE SLOWLY THROUGH THE AREA ON SATURDAY WITH SOME SHOWERS AND A
SLIGHT CHANCE OF A THUNDERSTORM WITH TEMPERATURES AGAIN RANGING
THROUGH THE 70S NORTHEAST TO THE LOWER 80S SOUTHWEST. EVEN WARMER
AND MORE HUMID CONDITIONS ARE EXPECTED SUNDAY INTO NEXT WEEK...WITH
DAILY CHANCES FOR SHOWERS AND THUNDERSTORMS...MAINLY DURING THE
AFTERNOON AND EVENING HOURS.
&&
.NEAR TERM /UNTIL 6 AM SATURDAY MORNING/...
AS OF 1035 PM EDT FRIDAY...FORECAST IS IN GOOD SHAPE AND ONLY MINOR
ADJUSTMENTS WERE MADE FOR CLOUD COVER AND HOURLY SFC TEMPERATURE
TRENDS. THE LATE EVENING BEGINS CLEAR TO PARTLY CLOUDY...BUT
CLOUD COVER WILL INCREASE AFTER MIDNIGHT AS DEBRIS CLOUDS FROM A
MESOSCALE CONVECTIVE COMPLEX AND ITS ASSOCIATED MID-LEVEL
VORTICITY CENTER OVER THE UPPER GREAT LAKES RIDES EAST-
SOUTHEASTWARD ALONG A DEVELOPING WARM FRONTAL BOUNDARY OVER OUR
AREA. LOW TEMPS WILL RUN RIGHT AROUND SEASONAL NORMALS IN THE 50S
TO NEAR 60 IN THE VALLEYS. THE INCREASE IN HIGH CLOUDS SHOULD
PRECLUDE RADIATIONAL FOG FORMATION OVERNIGHT. WINDS ARE NEARLY
CALM ACROSS THE REGION AT 02Z AND WILL REMAIN SO THRU THE
REMAINDER OF TONIGHT.
&&
.SHORT TERM /6 AM SATURDAY MORNING THROUGH SUNDAY NIGHT/...
AS OF 323 PM EDT FRIDAY...SATURDAY...MODERATE CONFIDENCE CONTINUES
THAT WE`LL SEE SOME SOME SHOWERS AND A SLIGHT CHANCE OF A
THUNDERSTORM AS THE DECAYING MCV AND SHORT WAVE TROF MOVES ACROSS
THE REGION DURING MIDDAY INTO THE EARLY EVENING. MODEL GUIDANCE
HAS BEEN STRUGGLING WITH THE PLACEMENT OF THIS FEATURE WITH THE
GFS MORE WIDESPREAD AND FURTHER SOUTH AND THE NAM FURTHER NORTH.
HAVE PLAYED IT MORE TOWARD THE GFS/MAV SOLUTION AS RAP ANALYSIS
SHOWS SIGNIFICANT MCV HAS FORMED. SO HIGHER POPS THAN WHAT THE NAM
MOS SUGGESTS AND SLIGHT COOLER TEMPERATURES. HAVE STAYED MAINLY
NEAR 80 WITH COOLER TEMPS NORTHEAST AND WARMER SOUTHWEST. WHERE
CLOUDS/SHOWERS HANG ON IT COULD BE 5 DEGREES COOLER AND WHERE THEY
DISSIPATE 5 DEGREES WARMER.
IN THE ABSENCE OF ANY LARGE SCALE FORCING...ANY CONVECTIVE
ACTIVITY WILL DISSIPATE GOING INTO THE EVENING AND OVERNIGHT
HOURS SAT NIGHT WITH LOWS MAINLY IN THE 60S.
ON SUNDAY...MORE TYPICAL ISOLATED TO SCATTERED AIRMASS TYPE PULSE
SHOWERS AND THUNDERSTORMS WILL BE POSSIBLE AGAIN ON SUNDAY MAINLY
IN THE MID TO LATE AFTERNOON/EVENING WITH ACTIVITY SETTLING DOWN
OVERNIGHT SUNDAY NIGHT. CAPE VALUES NOT ALL THAT IMPRESSIVE (BELOW
100 J/KG) WITH GFS SUGGESTING A CAPPING SUBSIDENCE INVERSION MAY
BE IN PLACE SO KEPT A MINIMAL CHANCE POPS IN THE FORECAST. IT
SHOULD BE CONSIDERABLY WARMER AND MORE HUMID AIR PUSHES IN AS THE
WARM FRONT LIFTS NORTHEAST SUNDAY WITH HIGHS IN THE 80S.
SUNDAY NIGHT SHOULD BE VERY MILD WITH READINGS IN THE 60S PERHAPS NEAR 70
AT BTV WITH WARM AND HUMID AIR FIRMLY ENTRENCHED.
&&
.LONG TERM /MONDAY THROUGH FRIDAY/...
AS OF 350 PM EDT FRIDAY...LARGE SCALE PATTERN WL CONTINUE TO
SUPPORT MID/UPPER LVL RIDGE ACRS THE SE CONUS WITH FAST WESTERLY
FLW ALOFT NEAR THE INTERNATIONAL BORDER THRU EARLY NEXT WEEK. BY
MID TO LATE NEXT WEEK ALL GUIDANCE SUGGESTS A PATTERN CHANGE WITH
DEVELOPMENT OF FULL LATITUDE TROF ACRS THE GREAT LAKES/EASTERN
CONUS AND LARGE RIDGE OVER THE INTER-MOUNTAIN WEST. THIS WL RESULT
IN MUCH ABOVE NORMAL TEMPS FOR MONDAY/TUESDAY WITH CHCS FOR
AFTN/EVENING SHOWERS/STORMS...WITH A TREND TWD COOLER AND WETTER
CONDITIONS BY LATE NEXT WEEK...AS TROF DEVELOPS AND SFC LOW PRES
IMPACTS OUR FA. PROGGED 85H TEMPS NEAR 16C AND 925MB TEMPS BTWN
20-22C ON MONDAY/TUESDAY...SUPPORTS HIGHS WELL INTO THE 80S WITH
EVEN A FEW LOWER 90S POSSIBLE IN THE WARMER VALLEY LOCATIONS. IN
ADDITION...PROGGED SFC DWPTS ARE EXPECTED TO BE IN THE MID/UPPER
60S...CREATING VERY MUGGY CONDITIONS...ESPECIALLY ON MONDAY. THIS
HEAT/HUMIDITY WL HELP TO PRODUCE SOME MODEST CAPE
VALUES...COMBINED WITH EMBEDDED 5H VORTS WL HELP IN THE
DEVELOPMENT OF AFTN/EVENING SHOWERS/STORMS. WL CONT TO MENTION CHC
POPS ATTM...WITH MAIN FOCUS DURING THE PEAK HEATING HRS. ANY
STORMS THAT DUE DEVELOP WL HAVE THE POTENTIAL TO PRODUCE LOCALIZED
HEAVY DOWNPOURS WITH PW VALUES BTWN 1.50 AND 1.75". BETTER
DYNAMICS AND MOISTURE ARRIVES BY LATE NEXT WK...AS MID/UPPER LVL
TROF DEVELOPS OVER THE GREAT LAKES. STILL SOME UNCERTAINTY OF
MAGNITUDE AND POSITION OF SYSTEM ALONG WITH AVAILABLE
MOISTURE...THEREFORE WL MENTION CHC POPS ATTM...WITH TEMPS
DROPPING BACK TO NEAR NORMAL. EXPECT ABOVE NORMAL LOW TEMPS THRU
THE PERIOD...GIVEN AMOUNT OF BL MOISTURE AND POTENTIAL FOR
CLOUDS/PRECIP...MAINLY IN THE U50S MTNS TO NEAR 70F CPV/SLV.
&&
.AVIATION /03Z SATURDAY THROUGH WEDNESDAY/...
THROUGH 00Z SUNDAY...MAINLY VFR THROUGH THE OVERNIGHT HOURS
THOUGH MID TO HIGH-LEVEL CLOUDINESS WILL BE ON THE INCREASE
PARTICULARLY AFTER MIDNIGHT. WINDS WILL BE LIGHT AND VARIABLE
UNDER BROAD SFC RIDGING. FOR SATURDAY...EXPECTING SHOWERS AND
THUNDERSTORMS AND DEVELOPING SOUTHEASTWARD WITH TIME. EXACT TIMING
ON THE ONSET OF PRECIPITATION IS DIFFICULT IT IS DEPENDENT ON WHAT
EVOLVES WITH THE ONGOING CONVECTION ACROSS THE NORTHERN
PLAINS/GREAT LAKES REGION TONIGHT. HOWEVER BASED ON PRESENT
INDICATIONS THIS APPEARS TO BE IN THE 13-18Z TIMEFRAME. FOR NOW
HAVE TREATED WITH VCSH DURING THAT PERIOD OF TIME. POTENTIAL FOR
MVFR VISIBILITIES (BRIEF IFR VISIBILITIES POSSIBLE IN
STEADIER/HEAVIER RAIN). WINDS WILL BE SOUTH/SOUTHWEST UNDER
10KTS...EXCEPT LIGHT/VARIABLE AT MSS.
OUTLOOK 00Z SUNDAY THROUGH TUESDAY... MAINLY VFR CONDITIONS WL PREVAIL
THRU THE TIME PERIOD WITH THE EXCEPTION OF BRIEF MVFR/IFR IN THE
HEAVIER SHOWERS/STORMS. BEST CHCS FOR STORMS WL BE DURING THE
AFTERNOON AND EARLY EVENING HRS THRU TUESDAY. IN ADDITION...SOME
PATCHY EARLY MORNING FOG/BR WITH MVFR/IFR WL BE POSSIBLE IF ANY
TAF SITE RECIEVES HEAVY RAINFALL FROM CONVECTION DURING THE
DAYTIME. EXPECT MAINLY SOUTHERLY WINDS THRU THE PERIOD.
&&
.EQUIPMENT...
OBSERVATIONS FROM RUTLAND-SOUTHERN VERMONT REGIONAL AIRPORT
(KRUT) REMAIN UNAVAILABLE DUE TO A TELEPHONE COMMS LINE ISSUE. THE
FAA AOCC IS AWARE OF THE ISSUE...BUT THERE IS NO ESTIMATE AVAILABLE
AT THIS TIME AS TO WHEN THIS COMMS OUTAGE WILL BE FIXED.
&&
.BTV WATCHES/WARNINGS/ADVISORIES...
VT...NONE.
NY...NONE.
&&
$$
SYNOPSIS...SISSON
NEAR TERM...BANACOS/SISSON
SHORT TERM...SISSON
LONG TERM...TABER
AVIATION...TABER/LOCONTO
EQUIPMENT...
AREA FORECAST DISCUSSION
NWS BURLINGTON VT
707 PM EDT FRI JUN 21 2013
.SYNOPSIS...
HIGH PRESSURE ANCHORED OFF THE ATLANTIC COAST WILL KEEP THE NORTH
COUNTRY DRY TODAY WITH PARTLY TO MOSTLY SUNNY SKIES THIS AFTERNOON
AND TEMPERATURES IN THE MID 70S TO LOWER 80S. A WARM FRONT WILL
MOVE SLOWLY THROUGH THE AREA ON SATURDAY WITH SOME SHOWERS AND A
SLIGHT CHANCE OF A THUNDERSTORM WITH TEMPERATURES AGAIN RANGING
THROUGH THE 70S NORTHEAST TO THE LOWER 80S SOUTHWEST. EVEN WARMER
AND MORE HUMID CONDITIONS ARE EXPECTED SUNDAY INTO NEXT WEEK...WITH
DAILY CHANCES FOR SHOWERS AND THUNDERSTORMS...MAINLY DURING THE
AFTERNOON AND EVENING HOURS.
&&
.NEAR TERM /UNTIL 6 AM SATURDAY MORNING/...
AS OF 705 PM EDT FRIDAY...FORECAST IS IN GOOD SHAPE AND ONLY MINOR
ADJUSTMENTS FOR CLOUD COVER AND HOURLY TEMPERATURE TRENDS. TONIGHT
BEGINS WITH CLEAR TO PARTLY CLOUDY SKIES THIS EVENING...BUT CLOUD
COVER WILL INCREASE AFTER MIDNIGHT AS DEBRIS CLOUDS FROM A
MESOSCALE CONVECTIVE COMPLEX AND ITS ASSOCIATED VORTICITY OVER
THE UPPER GREAT LAKES RIDES EAST-SOUTHEASTWARD ALONG THE A
DEVELOPING WARM FRONTAL BOUNDARY OVER OUR AREA. TEMPS WILL RUN
RIGHT AROUND SEASONAL NORMALS IN THE 50S TO NEAR 60 IN THE
VALLEYS. THE INCREASE IN HIGH CLOUDS SHOULD PRECLUDE RADIATIONAL
FOG.
&&
.SHORT TERM /6 AM SATURDAY MORNING THROUGH SUNDAY NIGHT/...
AS OF 323 PM EDT FRIDAY...SATURDAY...MODERATE CONFIDENCE CONTINUES
THAT WE`LL SEE SOME SOME SHOWERS AND A SLIGHT CHANCE OF A
THUNDERSTORM AS THE DECAYING MCV AND SHORT WAVE TROF MOVES ACROSS
THE REGION DURING MIDDAY INTO THE EARLY EVENING. MODEL GUIDANCE
HAS BEEN STRUGGLING WITH THE PLACEMENT OF THIS FEATURE WITH THE
GFS MORE WIDESPREAD AND FURTHER SOUTH AND THE NAM FURTHER NORTH.
HAVE PLAYED IT MORE TOWARD THE GFS/MAV SOLUTION AS RAP ANALYSIS
SHOWS SIGNIFICANT MCV HAS FORMED. SO HIGHER POPS THAN WHAT THE NAM
MOS SUGGESTS AND SLIGHT COOLER TEMPERATURES. HAVE STAYED MAINLY
NEAR 80 WITH COOLER TEMPS NORTHEAST AND WARMER SOUTHWEST. WHERE
CLOUDS/SHOWERS HANG ON IT COULD BE 5 DEGREES COOLER AND WHERE THEY
DISSIPATE 5 DEGREES WARMER.
IN THE ABSENCE OF ANY LARGE SCALE FORCING...ANY CONVECTIVE
ACTIVITY WILL DISSIPATE GOING INTO THE EVENING AND OVERNIGHT
HOURS SAT NIGHT WITH LOWS MAINLY IN THE 60S.
ON SUNDAY...MORE TYPICAL ISOLATED TO SCATTERED AIRMASS TYPE PULSE
SHOWERS AND THUNDERSTORMS WILL BE POSSIBLE AGAIN ON SUNDAY MAINLY
IN THE MID TO LATE AFTERNOON/EVENING WITH ACTIVITY SETTLING DOWN
OVERNIGHT SUNDAY NIGHT. CAPE VALUES NOT ALL THAT IMPRESSIVE (BELOW
100 J/KG) WITH GFS SUGGESTING A CAPPING SUBSIDENCE INVERSION MAY
BE IN PLACE SO KEPT A MINIMAL CHANCE POPS IN THE FORECAST. IT
SHOULD BE CONSIDERABLY WARMER AND MORE HUMID AIR PUSHES IN AS THE
WARM FRONT LIFTS NORTHEAST SUNDAY WITH HIGHS IN THE 80S.
SUNDAY NIGHT SHOULD BE VERY MILD WITH READINGS IN THE 60S PERHAPS NEAR 70
AT BTV WITH WARM AND HUMID AIR FIRMLY ENTRENCHED.
&&
.LONG TERM /MONDAY THROUGH FRIDAY/...
AS OF 350 PM EDT FRIDAY...LARGE SCALE PATTERN WL CONTINUE TO
SUPPORT MID/UPPER LVL RIDGE ACRS THE SE CONUS WITH FAST WESTERLY
FLW ALOFT NEAR THE INTERNATIONAL BORDER THRU EARLY NEXT WEEK. BY
MID TO LATE NEXT WEEK ALL GUIDANCE SUGGESTS A PATTERN CHANGE WITH
DEVELOPMENT OF FULL LATITUDE TROF ACRS THE GREAT LAKES/EASTERN
CONUS AND LARGE RIDGE OVER THE INTER-MOUNTAIN WEST. THIS WL RESULT
IN MUCH ABOVE NORMAL TEMPS FOR MONDAY/TUESDAY WITH CHCS FOR
AFTN/EVENING SHOWERS/STORMS...WITH A TREND TWD COOLER AND WETTER
CONDITIONS BY LATE NEXT WEEK...AS TROF DEVELOPS AND SFC LOW PRES
IMPACTS OUR FA. PROGGED 85H TEMPS NEAR 16C AND 925MB TEMPS BTWN
20-22C ON MONDAY/TUESDAY...SUPPORTS HIGHS WELL INTO THE 80S WITH
EVEN A FEW LOWER 90S POSSIBLE IN THE WARMER VALLEY LOCATIONS. IN
ADDITION...PROGGED SFC DWPTS ARE EXPECTED TO BE IN THE MID/UPPER
60S...CREATING VERY MUGGY CONDITIONS...ESPECIALLY ON MONDAY. THIS
HEAT/HUMIDITY WL HELP TO PRODUCE SOME MODEST CAPE
VALUES...COMBINED WITH EMBEDDED 5H VORTS WL HELP IN THE
DEVELOPMENT OF AFTN/EVENING SHOWERS/STORMS. WL CONT TO MENTION CHC
POPS ATTM...WITH MAIN FOCUS DURING THE PEAK HEATING HRS. ANY
STORMS THAT DUE DEVELOP WL HAVE THE POTENTIAL TO PRODUCE LOCALIZED
HEAVY DOWNPOURS WITH PW VALUES BTWN 1.50 AND 1.75". BETTER
DYNAMICS AND MOISTURE ARRIVES BY LATE NEXT WK...AS MID/UPPER LVL
TROF DEVELOPS OVER THE GREAT LAKES. STILL SOME UNCERTAINTY OF
MAGNITUDE AND POSITION OF SYSTEM ALONG WITH AVAILABLE
MOISTURE...THEREFORE WL MENTION CHC POPS ATTM...WITH TEMPS
DROPPING BACK TO NEAR NORMAL. EXPECT ABOVE NORMAL LOW TEMPS THRU
THE PERIOD...GIVEN AMOUNT OF BL MOISTURE AND POTENTIAL FOR
CLOUDS/PRECIP...MAINLY IN THE U50S MTNS TO NEAR 70F CPV/SLV.
&&
.AVIATION /23Z FRIDAY THROUGH WEDNESDAY/...
THROUGH 00Z SUNDAY...MAINLY VFR THROUGH THE OVERNIGHT HOURS
THOUGH MID TO HIGH-LEVEL CLOUDINESS WILL BE ON THE INCREASE
PARTICULARLY AFTER MIDNIGHT. WINDS WILL BE LIGHT AND VARIABLE
UNDER BROAD SFC RIDGING. FOR SATURDAY...EXPECTING SHOWERS AND
THUNDERSTORMS AND DEVELOPING SOUTHEASTWARD WITH TIME. EXACT TIMING
ON THE ONSET OF PRECIPITATION IS DIFFICULT IT IS DEPENDENT ON WHAT
EVOLVES WITH THE ONGOING CONVECTION ACROSS THE NORTHERN
PLAINS/GREAT LAKES REGION TONIGHT. HOWEVER BASED ON PRESENT
INDICATIONS THIS APPEARS TO BE IN THE 13-18Z TIMEFRAME. FOR NOW
HAVE TREATED WITH VCSH DURING THAT PERIOD OF TIME. POTENTIAL FOR
MVFR VISIBILITIES (BRIEF IFR VISIBILITIES POSSIBLE IN
STEADIER/HEAVIER RAIN). WINDS WILL BE SOUTH/SOUTHWEST UNDER
10KTS...EXCEPT LIGHT/VARIABLE AT MSS.
OUTLOOK 00Z SUNDAY THROUGH TUESDAY... MAINLY VFR CONDITIONS WL PREVAIL
THRU THE TIME PERIOD WITH THE EXCEPTION OF BRIEF MVFR/IFR IN THE
HEAVIER SHOWERS/STORMS. BEST CHCS FOR STORMS WL BE DURING THE
AFTERNOON AND EARLY EVENING HRS THRU TUESDAY. IN ADDITION...SOME
PATCHY EARLY MORNING FOG/BR WITH MVFR/IFR WL BE POSSIBLE IF ANY
TAF SITE RECIEVES HEAVY RAINFALL FROM CONVECTION DURING THE
DAYTIME. EXPECT MAINLY SOUTHERLY WINDS THRU THE PERIOD.
&&
.EQUIPMENT...
OBSERVATIONS FROM RUTLAND-SOUTHERN VERMONT REGIONAL AIRPORT
(KRUT) REMAIN UNAVAILABLE DUE TO A TELEPHONE COMMS LINE ISSUE. THE
FAA AOCC IS AWARE OF THE ISSUE...BUT THERE IS NO ESTIMATE AVAILABLE
AT THIS TIME AS TO WHEN THIS COMMS OUTAGE WILL BE FIXED.
&&
.BTV WATCHES/WARNINGS/ADVISORIES...
VT...NONE.
NY...NONE.
&&
$$
SYNOPSIS...SISSON
NEAR TERM...BANACOS/SISSON
SHORT TERM...SISSON
LONG TERM...TABER
AVIATION...TABER/LOCONTO
EQUIPMENT...
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
1106 PM EDT FRI JUN 21 2013
.SYNOPSIS...
A SLOW-MOVING COASTAL FRONT JUST OFFSHORE...WILL DRIFT WEST AND
ONSHORE LATE TONIGHT AND SATURDAY...INCREASING THE POTENTIAL FOR
SHOWERS AND THUNDERSTORMS. TYPICAL SUMMERTIME WEATHER IS EXPECTED
TO RETURN NEXT WEEK WITH BERMUDA HIGH PRESSURE...THE PIEDMONT
TROUGH AND THE DAILY SEA BREEZE...BECOMING THE DOMINANT SURFACE
FEATURES. DIURNALLY INDUCED CONVECTION WILL BECOME THE NORM DURING
THIS TIME PERIOD.
&&
.NEAR TERM /UNTIL 6 AM SATURDAY MORNING/...
AS OF 1045 PM FRIDAY...AS WE MOVE FURTHER INTO THE PRE-DAWN
SATURDAY HOURS...CONVECTION ALONG AND AHEAD OF THE COASTAL FRONT
JUST OFFSHORE...WILL OVERSPREAD THE COASTAL AREAS OF THE ILM CWA.
AS SEEN WITH LOCAL AND ADJACENT 88DS...THE CONVECTION FALLS APART
THE FURTHER INLAND IT TRACKS DUE TO THE DRIER AIR MASS IT
ENCOUNTERS. WITH TIME AND AFTER THIS PERIOD...THE AIRMASS OVER
INLAND LOCATIONS WILL BECOME SATURATED AND PRIMED FOR EXTENDED
CONVECTION. TIMING ISSUES CONTINUE FOR THE SPREADING INLAND OF
THE 50-70 POPS OVERNIGHT INTO SATURDAY. LATEST SREF PROBS FOR
MEASURE-ABLE PCPN ILLUSTRATES DRAMATICALLY INCREASING POPS TOWARD
DAYBREAK ACROSS THE MAJORITY OF THE ILM CWA. MIN TEMP GUIDANCE
EARLIER TWEAKED WILL REMAIN AS IS. THE KLTX VWP AND 00Z SOUNDINGS
FROM CHS AND MHX INDICATE AN ONSHORE FLOW SFC THRU AT LEAST 20K
FEET...INDICATIVE OF A SUBTROPICAL/TROPICAL AIR MASS BEING
ADVECTED ACROSS THE FA. 00Z PWS HAVE ALSO INCREASED...UP TO 1.87
INCHES AT MHX AND 1.68 INCHES AT CHS. PWS WILL LIKELY FURTHER RISE
OVERNIGHT...AND THUS WILL CONTINUE TO HIGHLIGHT PONDING OF WATER
POSSIBLE FROM HEAVY DOWNPOURS TONIGHT INTO SATURDAY IN THE HWO.
&&
.SHORT TERM /6 AM SATURDAY MORNING THROUGH SUNDAY NIGHT/...
AS OF 300 PM FRIDAY...THE MAIN FORECAST CHALLENGE WILL BE CENTERED
AROUND POPS MAINLY FOR SATURDAY AS A SEEMINGLY EVER PRESENT FRONT
FINALLY MAKES A MOVE INLAND. I HAVE TRENDED TOWARD THE MORE
AGGRESSIVE MET/NAM GUIDANCE FOR POPS WHICH WARRANT AN INCREASE FOR
SATURDAY`S VALUES. THIS CALLS FOR AN INCREASE IN CLOUD COVER AS
WELL WHILE LEANING TOWARD THE LOWER NUMBERS ALONG THE COAST FOR
HIGHS. AS FOR SATURDAY NIGHT AND SUNDAY THE FRONT WILL BECOME
ABSORBED INTO THE SOUTHERLY SYNOPTIC FLOW AND POPS WILL BE
ADDRESSED ON A MORE TYPICAL FASHION OF HIGHER VALUES BEING IN THE
AFTERNOON AND EARLY EVENING HOURS.
&&
.LONG TERM /MONDAY THROUGH FRIDAY/...
AS OF 300 PM FRIDAY...UPPER LEVEL HIGH PRESSURE JUST OFF THE
CAROLINA COAST MONDAY AND TUESDAY. THERE MAY BE A WEAKNESS ON ITS
WESTERN PERIPHERY DUE TO LEFTOVER REMNANTS OF THE UPPER LOW OVER
THE WRN PART OF THE CAROLINAS CURRENTLY. AT THE SURFACE HIGH
PRESSURE TO COVER A BROAD EXPANSE OF THE WEST ATLANTIC. THE
ORIENTATION OF THE HIGH WILL BE WEST TO EAST ELONGATED...WHICH IS
NOT OPTIMAL FOR MOISTURE ADVECTION INTO THE REGION. EVEN SO A
FAIRLY SEASONABLE AND DIURNAL COVERAGE OF CONVECTION SEEMS LIKELY.
WED AND THURS TRANSITIONAL DAYS ALOFT WITH RIDGING BECOMING BROAD
ACROSS THE NATIONS MIDSECTION EARLY ON FOLLOWED BY LARGE INCREASE
IN AMPLITUDE OVER WRN STATES ON THURSDAY. THE TROUGHINESS
DOWNSTREAM OVER THE EAST WILL BE CLOSED OFF QUICKLY PREVENTING
MUCH AMPLITUDE INCREASE/LOCAL EFFECTS. INSTEAD A BROAD AND WEAK
NORTHWESTERLY FLOW DEVELOPS. SURFACE PIEDMONT TROUGHINESS DEVELOPS
AS WELL. IN THE END THE FORMER MAY ACT TO SLIGHTLY INHIBIT
CONVECTION WHILE THE LATTER TRIES TO INCREASE IT. END RESULT MAY
MEAN LITTLE SIGNIFICANT CHANGES IN RAIN CHANCES THROUGH MOST OF
THE PERIOD. ON FRIDAY TROUGHINESS APPEARS TO INCREASE IN AMPLITUDE
OVER THE EASTERN U.S.
&&
.AVIATION /03Z SATURDAY THROUGH WEDNESDAY/...
AS OF 00Z...PERIODS OF MVFR/IFR EXPECTED DUE TO ISOLATED TO
SCATTERED SHOWERS/THUNDERSTORMS...PERIODS OF LOWERED CIGS AND
PATCHY FOG THROUGH THE VALID PERIOD. OTHERWISE VFR.
TRICKY FORECAST ON TAP AS A NEARLY STALLED FRONT OFFSHORE CONTINUES
TO SLOWLY MOVES WEST-NORTHWESTWARD TOWARDS THE FORECAST AREA. THIS
IS ALLOWING FOR ISOLATED TO SCATTERED SHOWERS TO AFFECT THE
COASTAL SITES THIS EVENING AS SEEN FROM LATEST RADAR IMAGERY.
OVERALL...TREND WILL CONTINUE THROUGH THE VALID PERIOD...WITH
HEAVIER RAINFALL EXPECTED TO PUSH INWARD TO THE INLAND SITES BY
SATURDAY MORNING. PERIODS OF HEAVY RAINFALL...ALONG WITH
INTERMITTENT PERIODS OF LOWERED CIGS...ESPECIALLY INLAND
OVERNIGHT...AND PATCHY FOG...ARE ANTICIPATED TO REDUCE CONDITIONS
TO MVFR/IFR THROUGHOUT THE VALID PERIOD. THUNDERSTORM CHANCES WILL
INCREASE ON SATURDAY AS WELL...THOUGH GIVEN UNCERTAINTY HAVE OPTED
TO KEEP VCTS ATTM. AS FOR WINDS...NORTHEAST WINDS 5 TO 8 KTS
THROUGH LATE MORNING ON SATURDAY WILL GRADUALLY BECOME EAST-
SOUTHEAST ALONG THE COAST BY AFTERNOON WITH SUSTAINED WINDS AOB 8
KTS.
EXTENDED OUTLOOK...ISOLATED TO SCATTERED SHOWERS THROUGH WEDNESDAY
AS A STALLED FRONT LINGERS NEAR THE COAST. BETTER CHANCE OF
PRECIPITATION WILL BE IN THE AFTERNOON HOURS WITH LOCALIZED
PERIODS OF MVFR/IFR POSSIBLE.
&&
.MARINE...
NEAR TERM /THROUGH TONIGHT/...
AS OF 1045 PM FRIDAY...THE APPROACH AND EVENTUAL PASSAGE OF THE
COASTAL FRONT ONSHORE WILL GOVERN THE WINDS ACROSS THE ILM WATERS.
LOOKING AT A NE-E WIND AHEAD OF THE FRONT...SE-S WIND AFTER ITS
PASSAGE. SFC PG HAVING SOMEWHAT RELAXED AHEAD OF THE FRONT...
RESULTING WITH WIND SPEEDS AROUND 10 KT. HRRR AND NAM INDICATE A
TIGHTENING OF THE GRADIENT AFTER ITS PASSAGE...WITH WIND SPEEDS
AROUND 15 KT...POSSIBLY WITH GUSTS UP TO 20 KT. SIGNIFICANT SEAS
EARLY ON WILL INITIALLY DROP TO 2 TO 3 FT THRUOUT THE ILM
WATERS...THEN INCREASE TO 3 TO 4 FT ALONG AND AFTER THE COASTAL
FRONT PUSHES ONSHORE. THE NAM AND HRRR INDICATE THE FRONT TO PUSH
ONSHORE FROM CAPE FEAR NORTH AROUND DAYBREAK...AND THE REMAINING
WATERS SOUTH OF THE CAPE DURING DAYLIGHT SATURDAY.
SHORT TERM /SATURDAY THROUGH SUNDAY NIGHT/... AS OF 300 PM
FRIDAY...MAIN FORECAST CHALLENGE FOR THE MARINE COMMUNITY WILL
OCCUR EARLY IN THE PERIOD AS A FRONT THAT HAS BEEN LINGERING OFF
THE COAST MAKES A MOVE INLAND. WIND DIRECTION WILL BE A LOW
CONFIDENCE EVENT FOR SATURDAY UNTIL THE SYNOPTIC SOUTHEASTERLY
FLOW BECOMES THE DOMINANT FEATURE LATE SATURDAY. FOR NOW THE
COASTAL AREAS WILL SEE A WEST TO NORTHWEST FLOW EARLY WITH A
SOUTHEASTERLY FLOW ACROSS THE OUTER WATERS. ALL AREAS SHOULD SEE
SOUTHEASTERLY WINDS LATE SATURDAY. FOR SUNDAY A TYPICAL SUMMERTIME
PATTERN OF SOUTHERLY WINDS WILL PREVAIL. FOR THE MOST PART WIND
SPEEDS WILL REMAIN MORE REPRESENTATIVE OF SUMMER WITH 10-15 KNOTS
PROBABLY LEANING MORE TOWARD THE LOWER END OF THE RANGE. WAVEWATCH
SEAS REMAIN IN A 2-4 FOOT RANGE THROUGH THE PERIOD.
LONG TERM /MONDAY THROUGH WEDNESDAY/...
AS OF 300 PM FRIDAY...HIGH PRESSURE ACROSS THE WEST ALTAIC THE ENTIRE
TIME. THIS HIGH WILL EXTEND A RIDGE AXIS INTO THE CAROLINAS THROUGH
THE PERIOD THAT MAY VACILLATE IN BOTH STRENGTH AND LOCATION AT
TIMES. END RESULT WILL BE SMALL VARIATIONS IN WIND DIRECTION BETWEEN
SOUTH AND SOUTHWEST. WIND SPEED WILL SHOW LITTLE ENOUGH CHANGE THAT
A FORECAST OF ABOUT 10 KTS WILL HOLD FOR MOST OF THE TIME. WNA
GUIDANCE SHOWS A MINOR EASTERLY SWELL COMBINING WITH THE WIND WAVES
ON TUESDAY. OVERALL SEAS FORECAST HOWEVER TO REMAIN FAIRLY
UNCHANGING AT A GENERAL 2 TO 4 FT...HIGHEST OFFSHORE.
&&
.TIDES/COASTAL FLOODING...
AS OF 1100 PM FRIDAY...HIGH TIDE AND ASSOCIATED HIGHEST GAGE
READINGS HAVE COME AND BY NOW ACROSS THE BEACHES AND NOW ACROSS
ALONG THE CAPE FEAR RIVER. MYRTLE BEACH SPRINGMAID PIER ECLIPSED
7.05 FT MLLW...WRIGHTSVILLE BEACH JOHNNY MERCER PIER AT 5.7 FT
MLLW...AND THE WILMINGTON GAGE IN THE CAPE FEAR RIVER AROUND 5.8
FT MLLW. THE NEXT HIGH TIDE CYCLES SUSCEPTIBLE TO MINOR COASTAL
FLOODING WILL OCCUR ON SATURDAY...SUNDAY AND MONDAY DURING THE MID
TO LATE EVENING HOURS.
&&
.ILM WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
NC...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...SHK
NEAR TERM...TRA
SHORT TERM...SHK
LONG TERM...MBB
AVIATION...SGL
TIDES/COASTAL FLOODING...DCH
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
849 PM EDT FRI JUN 21 2013
.SYNOPSIS...
A SLOW-MOVING COASTAL FRONT JUST OFFSHORE...WILL DRIFT WEST AND
ONSHORE LATE TONIGHT AND SATURDAY...INCREASING THE POTENTIAL FOR
SHOWERS AND THUNDERSTORMS. TYPICAL SUMMERTIME WEATHER IS EXPECTED
TO RETURN NEXT WEEK WITH BERMUDA HIGH PRESSURE...THE PIEDMONT
TROUGH AND THE DAILY SEA BREEZE...BECOMING THE DOMINANT SURFACE
FEATURES. DIURNALLY INDUCED CONVECTION WILL BECOME THE NORM DURING
THIS TIME PERIOD.
&&
.NEAR TERM /UNTIL 6 AM SATURDAY MORNING/...
AS OF 745 AM FRIDAY...CONVECTION HAS WANED OVER LAND DUE TO MAINLY
2 REASONS. THE FURTHER INLAND THE CONVECTION TRACKS...THE DRIER
THE AIR MASS. THIS WILL TAKE SOME TIME MOISTENING UP. AND THE
OTHER REASON...THE DAYS INSOLATION IS OVER WITH. HAVE LOWERED POPS
DRAMATICALLY INLAND FOR THIS EVENING. THE COASTAL FRONTAL BOUNDARY
IS PROGGED TO MAKE SOME HEADWAY TO THE COAST TONIGHT INTO
SATURDAY. THIS FRONT COMBINED WITH FLARE UP OF CONVECTION ACROSS
THE WARM WATERS OF THE ATLANTIC...WILL DRIFT ONSHORE COMMENCING
LATER THIS EVENING...BUT MAINLY DURING THE PRE-DAWN SAT HOURS.
HAVE RE-ALIGNED THE TIMING OF 50-70 POPS OVERNIGHT INTO SATURDAY.
SREF ALSO ILLUSTRATES A WEAL LULL IN PCPN COVERAGE THIS
EVENING...RAMPING BACK UP OVERNIGHT INTO SATURDAY. MIN TEMP
GUIDANCE TWEAKED TO INCLUDE AROUND 70 FOR LOWS ALONG THE IMMEDIATE
BEACHES...ALL ELSE UNTOUCHED. THE KLTX VWP AND 00Z SOUNDINGS FROM
CHS AND MHX INDICATE AN ONSHORE FLOW SFC THRU 20K
FEET...INDICATIVE OF A SUBTROPICAL/TROPICAL AIR MASS BEING
ADVECTED ACROSS THE FA. 00Z PWS HAVE ALSO INCREASED...UP TO 1.87
INCHES AT MHX AND 1.68 INCHES AT CHS. PWS WILL LIKELY FURTHER RISE
OVERNIGHT...AND THUS WILL CONTINUE TO HIGHLIGHT PONDING OF WATER
POSSIBLE FROM HEAVY DOWNPOURS TONIGHT INTO SATURDAY IN THE HWO.
PREVIOUS DISCUSSION....................................
AS OF 300 PM FRIDAY...THE OFFSHORE FRONT IS BEGINNING TO MOVE
WESTWARD TOWARD THE COAST. ALTHOUGH WINDS ARE STILL NORTHEASTERLY AT
THE FRYING PAN SHOALS BUOY...RADAR AND SATELLITE SUGGEST LOW
PRESSURE IS DEVELOPING ALONG THE FRONT AND MOVING WESTBOUND. THIS
SHOULD BRING THE BOUNDARY ACROSS THE BUOY LOCATION AND INTO THE
COASTAL WATERS AROUND MIDNIGHT TONIGHT. ISOLATED SHOWERS HAVE
DEVELOPED IN THE HUMID AND SLIGHTLY UNSTABLE AIRMASS ALONG THE COAST
THIS AFTERNOON. THESE SHOWERS SHOULD CONTINUE PUSHING WEST-
SOUTHWESTWARD OVER THE NEXT SEVERAL HOURS BUT WILL DISSIPATE WITH
THE LOSS OF DAYLIGHT THIS EVENING.
FARTHER INLAND IT`S A COMPLETELY DIFFERENT AIRMASS WITH DEWPOINTS IN
THE 50S AND NEARLY SOLID SUNSHINE. THIS VERY DRY AIRMASS IS STILL
HANGING ON ALONG THE INTERSTATE 95 CORRIDOR WEST INTO THE CENTRAL
CAROLINAS...BUT WILL BE PUSHED OUT BY THE INCREASING ATLANTIC
MOISTURE OVERNIGHT.
THE SURFACE FRONT WILL BE PUSHED TOWARD THE COAST LATE TONIGHT BY
BERMUDA HIGH PRESSURE EXPANDING ACROSS THE WEST-CENTRAL ATLANTIC. A
RIBBON OF DEEP MID LEVEL MOISTURE (850-600 MB) OVER THE FRONT WILL
ALSO MOVE WESTWARD TONIGHT LIFTED NORTHWESTWARD BY THE FLOW AROUND A
WEAK UPPER LEVEL LOW ACROSS THE SOUTHERN APPALACHIANS. THIS PROMISES
TO BRING GOOD CHANCES OF SHOWERS TO THE COAST TONIGHT. (ESPECIALLY
LATE TONIGHT) FARTHER INLAND SHOWER CHANCES WILL RISE TO ONLY A
SLIGHT CHANCE VERY LATE TONIGHT ALONG THE I-95 CORRIDOR. LOWS SHOULD
FALL INTO THE UPPER 60S FOR MOST AREAS...WITH LOWER 70S ON THE
BEACHES.
&&
.SHORT TERM /6 AM SATURDAY MORNING THROUGH SUNDAY NIGHT/...
AS OF 300 PM FRIDAY...THE MAIN FORECAST CHALLENGE WILL BE CENTERED
AROUND POPS MAINLY FOR SATURDAY AS A SEEMINGLY EVER PRESENT FRONT
FINALLY MAKES A MOVE INLAND. I HAVE TRENDED TOWARD THE MORE
AGGRESSIVE MET/NAM GUIDANCE FOR POPS WHICH WARRANT AN INCREASE FOR
SATURDAY`S VALUES. THIS CALLS FOR AN INCREASE IN CLOUD COVER AS
WELL WHILE LEANING TOWARD THE LOWER NUMBERS ALONG THE COAST FOR
HIGHS. AS FOR SATURDAY NIGHT AND SUNDAY THE FRONT WILL BECOME
ABSORBED INTO THE SOUTHERLY SYNOPTIC FLOW AND POPS WILL BE
ADDRESSED ON A MORE TYPICAL FASHION OF HIGHER VALUES BEING IN THE
AFTERNOON AND EARLY EVENING HOURS.
&&
.LONG TERM /MONDAY THROUGH FRIDAY/...
AS OF 300 PM FRIDAY...UPPER LEVEL HIGH PRESSURE JUST OFF THE
CAROLINA COAST MONDAY AND TUESDAY. THERE MAY BE A WEAKNESS ON ITS
WESTERN PERIPHERY DUE TO LEFTOVER REMNANTS OF THE UPPER LOW OVER
THE WRN PART OF THE CAROLINAS CURRENTLY. AT THE SURFACE HIGH
PRESSURE TO COVER A BROAD EXPANSE OF THE WEST ATLANTIC. THE
ORIENTATION OF THE HIGH WILL BE WEST TO EAST ELONGATED...WHICH IS
NOT OPTIMAL FOR MOISTURE ADVECTION INTO THE REGION. EVEN SO A
FAIRLY SEASONABLE AND DIURNAL COVERAGE OF CONVECTION SEEMS LIKELY.
WED AND THURS TRANSITIONAL DAYS ALOFT WITH RIDGING BECOMING BROAD
ACROSS THE NATIONS MIDSECTION EARLY ON FOLLOWED BY LARGE INCREASE
IN AMPLITUDE OVER WRN STATES ON THURSDAY. THE TROUGHINESS
DOWNSTREAM OVER THE EAST WILL BE CLOSED OFF QUICKLY PREVENTING
MUCH AMPLITUDE INCREASE/LOCAL EFFECTS. INSTEAD A BROAD AND WEAK
NORTHWESTERLY FLOW DEVELOPS. SURFACE PIEDMONT TROUGHINESS DEVELOPS
AS WELL. IN THE END THE FORMER MAY ACT TO SLIGHTLY INHIBIT
CONVECTION WHILE THE LATTER TRIES TO INCREASE IT. END RESULT MAY
MEAN LITTLE SIGNIFICANT CHANGES IN RAIN CHANCES THROUGH MOST OF
THE PERIOD. ON FRIDAY TROUGHINESS APPEARS TO INCREASE IN AMPLITUDE
OVER THE EASTERN U.S.
&&
.AVIATION /01Z SATURDAY THROUGH WEDNESDAY/...
AS OF 00Z...PERIODS OF MVFR/IFR EXPECTED DUE TO ISOLATED TO
SCATTERED SHOWERS/THUNDERSTORMS...PERIODS OF LOWERED CIGS AND
PATCHY FOG THROUGH THE VALID PERIOD. OTHERWISE VFR.
TRICKY FORECAST ON TAP AS A NEARLY STALLED FRONT OFFSHORE CONTINUES
TO SLOWLY MOVES WEST-NORTHWESTWARD TOWARDS THE FORECAST AREA. THIS
IS ALLOWING FOR ISOLATED TO SCATTERED SHOWERS TO AFFECT THE
COASTAL SITES THIS EVENING AS SEEN FROM LATEST RADAR IMAGERY.
OVERALL...TREND WILL CONTINUE THROUGH THE VALID PERIOD...WITH
HEAVIER RAINFALL EXPECTED TO PUSH INWARD TO THE INLAND SITES BY
SATURDAY MORNING. PERIODS OF HEAVY RAINFALL...ALONG WITH
INTERMITTENT PERIODS OF LOWERED CIGS...ESPECIALLY INLAND
OVERNIGHT...AND PATCHY FOG...ARE ANTICIPATED TO REDUCE CONDITIONS
TO MVFR/IFR THROUGHOUT THE VALID PERIOD. THUNDERSTORM CHANCES WILL
INCREASE ON SATURDAY AS WELL...THOUGH GIVEN UNCERTAINTY HAVE OPTED
TO KEEP VCTS ATTM. AS FOR WINDS...NORTHEAST WINDS 5 TO 8 KTS
THROUGH LATE MORNING ON SATURDAY WILL GRADUALLY BECOME EAST-
SOUTHEAST ALONG THE COAST BY AFTERNOON WITH SUSTAINED WINDS AOB 8
KTS.
EXTENDED OUTLOOK...ISOLATED TO SCATTERED SHOWERS THROUGH WEDNESDAY
AS A STALLED FRONT LINGERS NEAR THE COAST. BETTER CHANCE OF
PRECIPITATION WILL BE IN THE AFTERNOON HOURS WITH LOCALIZED
PERIODS OF MVFR/IFR POSSIBLE.
&&
.MARINE...
NEAR TERM /THROUGH TONIGHT/...
AS OF 800 PM FRIDAY...THE APPROACH AND EVENTUAL PASSAGE OF THE
COASTAL FRONT ONSHORE WILL GOVERN THE WINDS ACROSS THE ILM WATERS.
LOOKING AT A NE-E WIND AHEAD OF THE FRONT...SE-S WIND AFTER ITS
PASSAGE. SFC PG HAVING SOMEWHAT RELAXED AHEAD OF THE FRONT...
RESULTING WITH WIND SPEEDS AROUND 10 KT. HRRR AND NAM INDICATE A
TIGHTENING OF THE GRADIENT AFTER ITS PASSAGE...WITH WIND SPEEDS
AROUND 15 KT...POSSIBLY AS HIGH AS 20 KT. SIGNIFICANT SEAS EARLY ON
WILL INITIALLY DROP TO 2 TO 3 FT THRUOUT THE ILM WATERS...THEN
INCREASE TO 2 TO 4 FT ALONG AND AFTER THE COASTAL FRONT PUSHES
ONSHORE. THE NAM AND HRRR INDICATE THE FRONT TO PUSH ONSHORE FROM
CAPE FEAR NORTH AROUND DAYBREAK...AND THE REMAINING WATERS SOUTH
OF THE CAPE DURING DAYLIGHT SATURDAY.
PREVIOUS DISCUSSION...............................................
AS OF 300 PM FRIDAY...THE FRONT OFFSHORE IS BEGINNING TO MOVE
WESTWARD AND SHOULD MOVE INTO THE COASTAL WATERS LATE TONIGHT. RADAR
AND SATELLITE SUGGEST AN AREA OF LOW PRESSURE HAS DEVELOPED ALONG
THE FRONT WITH A DISTINCT SWIRL NOTED 20-40 MILES EAST OF THE FRYING
PAN SHOALS BUOY. THIS CIRCULATION SHOULD ACCOMPANY THE FRONT
WESTWARD TONIGHT...BRINGING WAVES OF SHOWERS AND PERHAPS
THUNDERSTORMS TO THE COASTAL WATERS OVERNIGHT. MAINLY NORTHEAST
WINDS ARE EXPECTED TONIGHT 10-15 KNOTS...WITH 3-4 FT SEAS OUTSIDE OF
ANY STRONGER THUNDERSTORMS.
SHORT TERM /SATURDAY THROUGH SUNDAY NIGHT/...
AS OF 300 PM FRIDAY...MAIN FORECAST CHALLENGE FOR THE MARINE
COMMUNITY WILL OCCUR EARLY IN THE PERIOD AS A FRONT THAT HAS BEEN
LINGERING OFF THE COAST MAKES A MOVE INLAND. WIND DIRECTION WILL BE
A LOW CONFIDENCE EVENT FOR SATURDAY UNTIL THE SYNOPTIC SOUTHEASTERLY
FLOW BECOMES THE DOMINANT FEATURE LATE SATURDAY. FOR NOW THE COASTAL
AREAS WILL SEE A WEST TO NORTHWEST FLOW EARLY WITH A SOUTHEASTERLY
FLOW ACROSS THE OUTER WATERS. ALL AREAS SHOULD SEE SOUTHEASTERLY
WINDS LATE SATURDAY. FOR SUNDAY A TYPICAL SUMMERTIME PATTERN OF
SOUTHERLY WINDS WILL PREVAIL. FOR THE MOST PART WIND SPEEDS WILL
REMAIN MORE REPRESENTATIVE OF SUMMER WITH 10-15 KNOTS PROBABLY
LEANING MORE TOWARD THE LOWER END OF THE RANGE. WAVEWATCH SEAS
REMAIN IN A 2-4 FOOT RANGE THROUGH THE PERIOD.
LONG TERM /MONDAY THROUGH WEDNESDAY/...
AS OF 300 PM FRIDAY...HIGH PRESSURE ACROSS THE WEST ALTAIC THE ENTIRE
TIME. THIS HIGH WILL EXTEND A RIDGE AXIS INTO THE CAROLINAS THROUGH
THE PERIOD THAT MAY VACILLATE IN BOTH STRENGTH AND LOCATION AT
TIMES. END RESULT WILL BE SMALL VARIATIONS IN WIND DIRECTION BETWEEN
SOUTH AND SOUTHWEST. WIND SPEED WILL SHOW LITTLE ENOUGH CHANGE THAT
A FORECAST OF ABOUT 10 KTS WILL HOLD FOR MOST OF THE TIME. WNA
GUIDANCE SHOWS A MINOR EASTERLY SWELL COMBINING WITH THE WIND WAVES
ON TUESDAY. OVERALL SEAS FORECAST HOWEVER TO REMAIN FAIRLY
UNCHANGING AT A GENERAL 2 TO 4 FT...HIGHEST OFFSHORE.
&&
.TIDES/COASTAL FLOODING...
AS OF 745 PM FRIDAY...HIGH TIDE HAS PASSED ACROSS THE BEACHES WITH
MYRTLE BEACH SPRINGMAID PIER ECLIPSING 7.05 MLLW AND WRIGHTSVILLE
BEACH JOHNNY MERCER PIER AT 5.7 FT MLLW. LET THE BEACHES CFW
EXPIRE...BUT CONTINUED WITH THE CAPE FEAR RIVER CFW DUE TO THE
NORMAL HIGH TIDE CYCLE LAGGING BEHIND THE BEACHES OCCURRENCE.
PREVIOUS DISCUSSION...............................................
AS OF 300 PM FRIDAY...THE APPROACHING FULL MOON IS BRINGING LARGE
TIDAL RANGES TO THE AREA. THIS EVENING`S HIGH TIDE MAY ECLIPSE THE
MINOR COASTAL FLOODING LEVEL AT AREA BEACHES...AND THEN ABOUT 2-3
HOURS LATER THE LOWER CAPE FEAR RIVER AT DOWNTOWN WILMINGTON WILL
ALMOST DEFINITELY EXCEED ITS MINOR FLOOD CRITERIA.
ALONG THE BEACHES THE BEST CHANCE OF SEEING MINOR COASTAL FLOODING
WILL BE IN THE CAROLINA BEACH VICINITY AND ALSO NEAR PAWLEYS ISLAND
SC. SINCE SPECIFIC IMPACTS ARE NOT KNOWN AT EVERY BEACH LOCATION I
HAVE ELECTED TO PLACE THE ADVISORY IN EFFECT FOR ALL BEACHES EVEN
THOUGH SOME LOCATIONS LIKE MYRTLE BEACH ARE EXPECTED TO REMAIN ABOUT
3 INCHES (0.25 FT) BELOW THE DEFINED MINOR FLOOD CRITERIA OF 7.50 FT
MLLW.
THE FLOODING ON THE LOWER CAPE FEAR RIVER AT DOWNTOWN WILMINGTON
WILL REMAIN IN IN THE MINOR CATEGORY TONIGHT BUT MAY APPROACH 6.0
FEET MLLW. THIS CAN PUT AS MUCH AS 6 INCHES OF WATER ON PORTIONS OF
BATTLESHIP DRIVE ON THE WEST SIDE OF THE RIVER FROM DOWNTOWN.
&&
.ILM WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
NC...COASTAL FLOOD ADVISORY UNTIL 11 PM EDT THIS EVENING FOR NCZ107.
MARINE...NONE.
&&
$$
SYNOPSIS...SHK
NEAR TERM...DCH/TRA
SHORT TERM...SHK
LONG TERM...MBB
AVIATION...SGL
TIDES/COASTAL FLOODING...DCH/TRA
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
146 AM EDT THU JUN 20 2013
.SYNOPSIS...
HIGH PRESSURE WILL NOSE IN FROM THE NORTH...KEEPING A FRONT STALLED
OUT TO OUR SOUTH TODAY. THIS SHOULD ALLOW SOME DRIER AIR TO FILTER
INTO THE AREA FROM THE NORTH. THE LINGERING FRONT WILL NUDGE BACK TO
THE NORTH DURING FRIDAY AND THROUGH THE WEEKEND.
&&
.NEAR TERM /THROUGH THURSDAY/...
AS OF 1045 PM WEDNESDAY...CURRENT PCPN AND LATEST HRRR INDICATE POPS
WILL CONTINUE TO DROP ACROSS THE REGION LATE THIS EVENING AND
OVERNIGHT...AND TRANSITION TO A MORE STRATIFORM TYPE PCPN. IN
FACT...LATEST 88D AND SFC OBS INDICATE LOW LEVEL -SHRA OR -RA
AND DRIZZLE WITHIN THE LOW LEVEL NE-E FLOW BEGINNING TO DOMINATE
PCPN ACROSS THE IMMEDIATE COAST AND SOUTHERN PORTIONS OF THE ILM
CWA INTO THE PRE-DAWN THU HOURS. WILL CONTINUE TO USE THE LATEST
HRRR MODEL TO ILLUSTRATE THE CURRENT AND PROGGED LOCATION OF THE
FRONT...AND THE SENSIBLE WX PARAMETERS IN THE WAKE OF THE COLD
FRONT.
LOOKING AT THE LATEST SAT IMAGERY...DO NOT SEE THE CLEARING BEHIND
THE FRONT THAT MODELS TRY TO INFILTRATE ACROSS THE FA OVERNITE.
HOWEVER...THE CLOUDS WEST OF I-95 ARE OF THE HIGH LEVEL VARIETY.
AS A RESULT...HAVE BACKED DOWN WITH THE OPAQUE CLOUDINESS
ESPECIALLY INLAND. HOWEVER...IT CAN EASILY FILL BACK IN WITH LOW
LEVEL STRATUS. HAVE ONLY INCLUDED PATCHY FOG AT THIS
POINT...ANYTHING WORSE WILL HAVE TO BE MONITORED SINCE FOG NOT A
COMMON OCCURRENCE OUTSIDE OF PCPN DURING THIS TIME OF THE YEAR.
WILL KEEP MIN TEMPS IN THE 65 TO 70 DEGREE RANGE...WHERE LOWER
READINGS TO OCCUR WELL INLAND.
&&
.SHORT TERM /THURSDAY NIGHT THROUGH FRIDAY NIGHT/...
AS OF 3 PM WEDNESDAY...LATEST MODEL RUNS HEDGING TOWARD A
CLOUDIER AND WETTER FORECAST FOR THE COASTAL AREAS AS FRONT
LINGERS NEAR OR JUST SOUTH OF AREA THROUGH THE PERIOD AND THEN
MOVES BACK NORTH AND WEST. ALTHOUGH HIGH PRESSURE TRIES TO BUILD
DOWN FROM THE NORTH...IT LOOKS LIKE THE RIDGE TO THE SOUTH WILL
END UP PUSHING THE DIFFUSE BOUNDARY AND ASSOCIATED MOISTURE BACK
NORTH. THE HIGH PRESSURE TO THE NORTH WILL CONTINUE TO NOSE DOWN
INTO THE INLAND PORTIONS OF THE CAROLINAS BUT THERE WILL BE A
TIGHT GRADIENT BETWEEN THE TWO AIR MASSES...SLIGHTLY COOLER AND
MUCH DRIER TO THE NORTHWEST AND MUCH WETTER TO THE SOUTHEAST. THE
BIG QUESTION IS WHERE WILL THIS DIVIDING LINE END UP. PREVIOUS
MODEL RUNS KEPT OUR AREA IN THE DRIER AIR BUT LATEST RUNS ARE
TRENDING TO A WETTER FORECAST...MAINLY ALONG THE COAST. PCP WATER
VALUES WILL BE AS LOW AS ONE INCH BASICALLY WEST OF I95 AND UP TO
1.75 INCHES OR GREATER OVER NORTHEAST SOUTH CAROLINA COAST.
LOOKS LIKE OUR BEST CHC FOR DRIER NICER WEATHER WILL BE ON THURS
BEFORE BOUNDARY MAKES ITS PUSH NORTH. FOR NOW WILL KEEP ANY CHC OF
PCP JUST ALONG THE COAST AND PRIMARILY OVER COASTAL SOUTH
CAROLINA...BUT MAY END UP BEING A GOOD DEAL OF CLOUDS OVER MUCH OF
THE AREA EXCEPT INLAND COUNTIES...MAINLY WEST OF I95 WHERE DRIER
AND SUNNIER WEATHER SHOULD BE. BASICALLY ANY SHIFT IN THIS
BOUNDARY WILL CHANGE FORECAST QUITE A BIT AND THEREFORE MUCH
UNCERTAINTY EXISTS FOR FORECAST ACROSS THE COASTAL COUNTIES.
PCP ALONG THE COAST...CLOUDS AND NORTHEAST FLOW WILL KEEP TEMPS
BELOW NORMAL. TEMPS SHOULD REMAIN CLOSER TO 80 ALONG THE COAST TO
MID 80S INLAND. OVERNIGHT LOWS SHOULD BE IN THE MID 60S.
&&
.LONG TERM /SATURDAY THROUGH WEDNESDAY/...
AS OF 3 PM WEDNESDAY...SOME UNCERTAINTY REMAINS IN THE
EXTENDED...BUT GUIDANCE IN DECENT AGREEMENT FOR THE MOST PART IN A
DEVELOPING TYPICAL SUMMERTIME PATTERN...WITH RIDGING AT 500MB AND A
BERMUDA HIGH SITTING OFFSHORE. DURING NEXT WEEK...HIGH PRESSURE
OFFSHORE WILL COMBINE WITH BUILDING 1000-500MB THICKNESSES TO CREATE
A WARMING TREND...WITH TEMPS RISING TO ABOVE NORMAL..AND WIDESPREAD
90S ARE LIKELY EARLY NEXT WEEK. AT THE SAME TIME...THIS PATTERN
TYPICALLY SUPPORTS SCATTERED AFTN CONVECTION...AND NEXT WEEK SHOULD
BE NO DIFFERENT. WITHOUT ANY MEANINGFUL CAP...AND PWATS RISING TO
NEAR TWO INCHES...HAVE CHC/SCHC CONVECTION EACH AFTN...WANING
NOCTURNALLY.
THE BIGGEST QUESTION MARK IN THE EXTENDED THEN IS THE FIRST PORTION
OF THE PERIOD. COLD FRONT OFFSHORE WILL BE WEAKENING...AND AS HIGH
PRESSURE BUILDS WELL EAST...SYNOPTIC RETURN FLOW WILL PUSH THIS
BOUNDARY BACK TOWARDS THE COAST DURING SATURDAY...LIFTING NORTH OF
THE AREA ON SUNDAY. QUESTION MARKS REMAIN AS TO HOW STRONG THIS
BOUNDARY WILL BE...HOW MUCH MOISTURE WILL STILL BE ASSOCIATED WITH
IT...AND WHETHER A LOW PRESSURE WILL DEVELOP ALONG IT. ATTM WILL
CONTINUE TO SUPPORT THE ECMWF WHICH HAS BEEN THE MOST
CONSISTENT...BUT MAY BE A BIT DRY...AND WILL NOT INCLUDE ANY MENTION
OF LOW PRESSURE DEVELOPMENT...BUT WILL SUPPORT CHC POP SAT INTO SUN
AS THE TROUGH PUSHES ONSHORE. TEMPS WILL BE HINDERED DURING THE WKND
BY CLOUDS AND PRECIP...AND EXPECT LOW/MID 80S SAT BEFORE WARMING AS
SOME COLUMN DRYING OCCURS ON SUNDAY.
&&
.AVIATION /06Z THURSDAY THROUGH MONDAY/...
AS OF 06Z...MVFR/IFR CIGS ARE EXPECTED EARLY THIS MORNING AS
ABUNDANT LOW-LEVEL MOISTURE REMAINS IN PLACE ACROSS THE CWA. IFR
SEEMS MOST LIKELY TO OCCUR BETWEEN 09-12Z AT THE COASTAL TERMS...
WHILE THE LATEST GUIDANCE SUGGESTS KFLO/KLBT WILL REMAIN MVFR.
LOWERED CIGS MAY LINGER ALONG THE COAST THRU THE MORNING HOURS WITH
THE STALLED FRONT NEARBY AND CONTINUING SHOWERS OFFSHORE. CONDITIONS
SHOULD BECOME VFR AT ALL TERMS BY THE AFTN WITH E/NE WINDS 10-12
KT. HAVE INCLUDED VCSH FOR KMYR/KCRE DURING THE DAY BASED ON THE
POSITIONING OF THE FRONT AND THE POTENTIAL FOR PASSING -SHRA TO CLIP
THESE SITES. OTHERWISE...VFR SHOULD PERSIST THRU THE AFTN/EVENING
HOURS WITH WINDS BECOMING AOB 5 KTS AFTER SUNSET.
EXTENDED OUTLOOK...SLIGHT CHANCE OF SHOWERS FRIDAY THRU SUNDAY AS A
STALLED FRONTAL BOUNDARY LINGERS NEAR THE COAST. VFR ON MONDAY.
&&
.MARINE...
NEAR TERM /THROUGH TONIGHT/...
AS OF 1 AM THURSDAY...HAVE INCLUDED A SMALL CRAFT SHOULD EXERCISE
CAUTION HEADLINE FOR ALL WATERS THROUGH 22Z.
AS MENTIONED BY THE PRIOR FORECASTER...ONLY A FEW MODELS ARE
HANDLING THE CURRENT LOCATION OF THE COLD FRONT AND ITS SOUTHWARD
MOVEMENT. WILL STALL IT SOUTH AND WELL EAST AND OFFSHORE FROM THE
ILM COASTAL WATERS BY DAYBREAK THU...PER LATEST HRRR GUIDANCE. LOOK
FOR THE SFC PG TO TIGHTEN ACROSS THE AREA WATERS AS THE HIGH FLEXES
SOUTHWARD OVERNIGHT INTO THURSDAY. HAVE STAYED CLOSER TO THE HRRR
OUTPUT WITH A SOLID 15 KT AFTER MIDNIGHT WITH GUSTS UP TO 20 KT.
THE LATEST RUN OF LOCALLY PRODUCED SWAN HAS FINALLY COME CLOSER TO
CURRENT SEA CONDITIONS...AND WILL THEREFORE USE ITS OUTPUT FOR
THE OVERNIGHT INTO THURSDAY PERIOD. THE WIND DRIVEN 4 TO 6 SECOND
PERIOD WAVES WILL DOMINATE THE SIGNIFICANT SEAS OVERNIGHT INTO THU.
SHORT TERM /THURSDAY THROUGH FRIDAY NIGHT/...
AS OF 3 PM WEDNESDAY...HIGH PRESSURE WILL BUILD IN BEHIND FRONT
WHICH WILL SLOWLY SAG SOUTH INITIALLY AND THEN BACK NORTH BY
FRIDAY. THE PINCHED GRADIENT BETWEEN THE HIGH PRESSURE BUILDING
SOUTH AND STALLED FRONT OFF THE COAST WILL PRODUCE PERSISTENT
NORTHEAST WINDS AROUND 15 KT THURSDAY. THIS IN TURN WILL PRODUCE
SEAS IN THE 3 TO 5 FT RANGE MOST WATERS...BUT LOWER JUST SOUTH OF
CAPE FEAR WHICH REMAINS BLOCKED FROM NORTHEAST WINDS.
GRADIENT WILL RELAX A BIT LATE THURS INTO FRI WITH WINDS SUBSIDING
TO 10 TO 15 KTS THURS NIGHT AND CLOSER TO 10 KTS BY FRI. THIS WILL
ALLOW SEAS TO DROP DOWN TO 2 TO 4 FT. WINDS VEER AROUND AS
BOUNDARY LIFTS NORTH BECOMING MORE EAST TO SOUTHEAST THROUGH
FRIDAY ON EAST SIDE OF BOUNDARY. WINDS WILL REMAIN NORTHEAST 10
KTS OR LESS ON WEST SIDE OF LINGERING FRONT AND MORE SOUTHERLY UP
TO 15 KTS ON EAST SIDE OF BOUNDARY WHICH MAY INTERSECT RIGHT
THROUGH OUR LOCAL WATERS ON FRIDAY.
LONG TERM /SATURDAY THROUGH MONDAY/...
AS OF 3 PM WEDNESDAY...LIGHT NE WINDS SATURDAY WILL GRADUALLY TURN
TO THE SE AS COASTAL TROUGH/REMNANT FRONT PUSHES WEST ONSHORE DURING
THE DAY. THIS IS IN RESPONSE TO A BERMUDA HIGH PRESSURE BUILDING
ACROSS THE WESTERN ATLANTIC OCEAN...WHICH WILL THEN CONTROL THE
SYNOPTIC ENVIRONMENT THROUGH THE REMAINDER OF THE
EXTENDED...CREATING SW WINDS AROUND 10 KTS OVER THE WATERS. WITH THE
GRADIENT REMAINING RELATIVELY WEAK...WIND WAVE CONTRIBUTION TO THE
SPECTRUM WILL BE ONLY MINIMAL...AND THE COMBINATION OF WIND WAVES
(NE ON SATURDAY...SE SUN/MON) AND A GROWING SE SWELL WILL CREATE 2-4
FT SEAS THROUGH THE PERIOD.
&&
.ILM WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
NC...NONE.
MARINE...NONE.
&&
$$
NEAR TERM...DCH
SHORT TERM...RGZ
LONG TERM...JDW
AVIATION...BJR/RJD
AREA FORECAST DISCUSSION
NWS GRAND FORKS ND
1257 PM CDT THU JUN 20 2013
.UPDATE...
ISSUED AT 1257 PM CDT THU JUN 20 2013
MADE FURTHER ADJUSTMENTS TO POPS AS THE RAIN IN THE SOUTHEAST HAS
EXITED THE AREA AND MORE STORMS HAVE BEEN HEADING INTO THE
NORTHWESTERN COUNTIES. WITH CONTINUED DESTABILIZATION AS THE
AFTERNOON WEARS ON WILL KEEP THE TREND OF INCREASING POPS INTO THE
80 PERCENT AREA DURING THE AFTERNOON AND EVENING. THERE HAVE BEEN
REPORTS OF NEARLY 2 INCHES OF RAIN IN LESS THAN AN HOUR FROM THE
STORMS JUST TO THE WEST OF THE CWA. WITH THE RAIN LAST NIGHT AND
FFG VALUES LESS THAN 2 INCHES ACROSS MUCH OF THE CWA FROM THE
RED RIVER VALLEY WESTWARD...WILL PUT OUT A FLASH FLOOD WATCH
THROUGH 12Z SUNDAY. PWAT VALUES STAY HIGH AND THERE WILL BE
CONTINUED MINOR SHORTWAVES MOVING OUT AS THE UPPER LOW STAYS OVER
THE NORTHERN ROCKIES. FAR EASTERN COUNTIES HAVE HIGHER FLASH FLOOD
GUIDANCE VALUES SO WILL LEAVE OUT OF ANY WATCH FOR NOW. ALSO
TWEAKED TEMPS DOWN THIS AFTERNOON A BIT WITH CLOUD COVER KEEPING
TEMPS FROM CLIMBING QUITE AS FAST AS EXPECTED.
UPDATE ISSUED AT 943 AM CDT THU JUN 20 2013
CONVECTIVE COMPLEX OVER NORTH CENTRAL ND HAS STARTED TO MOVE INTO
OUR NORTHWESTERN COUNTIES...AND THERE HAS BEEN SOME ADDITIONAL
DEVELOPMENT SOUTHWARD TOWARDS VALLEY CITY. THERE HAS ALSO BEEN
SOME STORMS FIRING AROUND THE THIEF RIVER FALLS TO BEMIDJI AREAS.
BUMPED UP POPS SIGNIFICANTLY ACROSS THE NORTHWEST AND NORTHEAST.
THERE SHOULD BE A BREAK IN THE CENTRAL CWA THROUGH MID DAY BEFORE
MORE ACTIVITY MOVES IN LATER THIS AFTERNOON. LOWERED TEMPS JUST A
TAD FOR MORE PRECIP AND CLOUDS THAN EXPECTED...BUT THINK THERE
SHOULD STILL GET ENOUGH HEATING TO GET INTO THE UPPER 70S TO MID
80S WITH GOOD INSTABILITY DEVELOPING BY AFTERNOON. WILL CONTINUE
WITH SEVERE MENTION INTO THE AFTERNOON AND EVENING AND WILL
MONITOR PREDICTED QPF AMOUNTS GIVEN THE RECENT HEAVY RAINS OVER
THE SOUTHERN CWA AND IF WE NEED ANY FLOOD WATCH PRODUCTS LATER ON.
UPDATE ISSUED AT 710 AM CDT THU JUN 20 2013
NOT MUCH CHANGE TO PREVIOUS THINKING. TWEAKED POPS AND WX
ACCORDING TO CURRENT CONDITIONS AND LATEST HRRR GUIDANCE FOR THE
MORNING HOURS. PORTIONS OF SARGENT AND RANSOM COUNTY LIKELY
RECEIVED UP TO 8 INCHES OF RAIN...AND MAJOR FLOODING ISSUES ARE
BEING REPORTED. REPORTS ARE JUST COMING INTO THE OFFICE...AND
THERE ARE STILL A LOT OF UNKNOWNS AT THIS POINT. THE SEVERE THREAT
FOR THE MORNING HOURS SHOULD REMAIN SOUTH OF THE FA...ALTHOUGH
THERE IS A SEVERE BOW JUST SOUTH OF THE FA THAT WE WILL NEED TO
MONITOR.
ACTIVITY ACROSS NORTH CENTRAL NORTH DAKOTA WILL CONTINUE TO
PROPAGATE TO THE NORTH. IT MAY CLIP OUR NORTHWESTERN FA...AND WILL
MONITOR. THIS ACTIVITY IS CURRENTLY NOT SEVERE.
THE SEVERE THREAT IS STILL ON TRACK FOR LATER THIS AFTERNOON AND
OVERNIGHT. FAIRLY CONFIDENT THAT THERE WILL BE A BREAK IN ACTIVITY
TODAY...WHICH WOULD ALLOW HEATING AND MOISTURE RETURN...LEADING TO
AN ELEVATED SEVERE THREAT.
&&
.SHORT TERM...(TODAY THROUGH FRIDAY)
ISSUED AT 330 AM CDT THU JUN 20 2013
MAIN CONCERN WILL BE SEVERE THUNDER AND HEAVY RAIN POTENTIAL THIS
AFTERNOON AND OVERNIGHT.
AREA OF THUNDERSTORMS CURRENTLY ONGOING ACROSS THE SOUTHERN FA
(AND BUILDING INTO THE WESTERN FA) WHERE WATER VAPOR IMAGERY
INDICATES AN UPPER WAVE AND THE RAP INDICATES 30-40 KNOT 850MB JET
INDUCED BY THIS UPPER WAVE. ANTICIPATE THIS ACTIVITY TO CONTINUE
INTO THE DAYLIGHT HOURS AND THEN DISSIPATE WITH SUBSIDENCE BEHIND
THE WAVE. SEVERE POTENTIAL IS VERY LOW CONSIDERING WEAK
INSTABILITY. THE MAIN THREAT WILL BE HEAVY RAIN WITH PWATS AROUND
1.5 INCHES AND SLOW STORM MOTIONS.
ANTICIPATE A BREAK IN THE ACTIVITY DURING THE MID-DAY HOURS WHICH
SHOULD ALLOW FOR SOME HEATING AND MOISTURE ADVECTION...WITH MLCAPE
VALUES AOA 2000 J/KG SOME AREAS. FORCING FOR REDEVELOPMENT SHOULD
COME WITH A POSSIBLE MCV FROM ACTIVITY TO THE WEST (ACROSS
NORTHERN MONTANA) AS WELL AS AN UPPER WAVE FROM THE SOUTHWEST THAT
SOME MODEL INDICATE. PREFER TO FOLLOW THE ECMWF FOR DEWPOINT
VALUES CONSIDERING LACK OF EVAPOTRANSPIRATION DUE TO LATE CROPS
THIS YEAR. THIS SOLUTION WOULD HAVE MLCAPE 2000-2500 J/KG INTO SE
NORTH DAKOTA BY 21Z...WITH DECREASING INSTABILITY TO THE NORTH
AND EAST (AND THE INSTABILITY AXIS INTO NORTH CENTRAL NORTH
DAKOTA). MOST LIKELY SCENARIO IS THAT THUNDER INITIATES ALONG THE
LOW LEVEL BOUNDARY/DRY LINE ACROSS CENTRAL NORTH DAKOTA...AND
EVENTUALLY BECOMES SOME SORT OF MCS THAT BUILDS INTO THE HIGHER
STABILITY (WHICH MOST LIKELY WILL BE TO THE SOUTH). THE MAIN
THREATS WILL LIKELY BE LARGE HAIL AND ESPECIALLY WIND GUSTS. A
TORNADO OR TWO IS ALSO POSSIBLE...ESPECIALLY INITIALLY. OTHER
MODELS ARE MORE ROBUST WITH DEWPOINTS VALUES (INTO THE LOW/MID
70S...AND WELL NORTH INTO THE FA)...WHICH LIKELY ACCOUNTS FOR THEM
WANTING TO MOVE THE MCS TO THE EAST INTO NORTHERN
MINNESOTA...OPPOSED TO THE ECMWF WHICH MOVES THIS FEATURE INTO
SOUTHERN MINNESOTA. HEAVY RAIN ALSO A THREAT WITH PWATS ABOVE 1.5
INCHES. NOT SURE EXACTLY WHERE THE HEAVIEST RAIN WILL OCCUR
TONIGHT...BUT A FLASH FLOOD WATCH MAY BE NEEDED ACROSS THE
SOUTHERN FA WHERE THE HEAVY RAIN IS CURRENTLY OCCURRING.
.LONG TERM...(FRIDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 330 AM CDT THU JUN 20 2013
FRIDAY-SATURDAY NIGHT...REGION WILL BE IN SOUTHWEST FLOW
ALOFT...AND CONVECTIVE CHANCES WILL HINGE ON TIMING OF SHORTWAVES
EJECTING FROM THE WESTERN TROUGH. FOLLOWING THE ECMWF FOR
TIMING...KEPT THE LIKELY POPS FOR FRIDAY EVENING INTO SATURDAY
MORNING...AND AGAIN FOR SATURDAY NIGHT. SEVERE STORMS AGAIN A
POSSIBILITY...AND DEPENDENT ON INSTABILITY VALUES. THE SOUTHERN FA
APPEARS TO HAVE THE BEST CHANCE FOR SEVERE STORMS. HEAVY RAIN ALSO
A POSSIBILITY...AND FUTURE SHIFTS MAY NEED TO CONSIDER FLOOD/FLASH
FLOOD WATCHES DEPENDING ON WHAT HAPPENS TODAY.
SUNDAY-WEDNESDAY...LONG WAVE TROUGH RE-ESTABLISHES FARTHER WEST
OVER THE EASTERN PACIFIC. A LONG WAVE RIDGE BUILDS OVER THE
CENTRAL US BY THE END OF THE PERIOD. GFS AND ECMWF ARE SIMILAR
TIMING WISE AT 84 HOURS BUT THE ECMWF BECOMES THE FASTER SOLUTION
FOR THE REST OF THE PERIOD. WILL USE A BLEND OF THE ECMWF AND GFS.
PRECIPITATION IS A LITTLE FASTER WITH TODAYS RUNS AND WILL BE SUED.
LITTLE CHANGE TO TEMPS THROUGH THE PERIOD COMPARED TO YESTERDAY
PACKAGE.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z FRIDAY AFTERNOON)
ISSUED AT 1257 PM CDT THU JUN 20 2013
VFR CIGS AND VSBYS ARE EXPECTED ACROSS THE REGION FOR THE MOST PART
TODAY...HOWEVER THUNDERSTORM ACTIVITY WILL INCREASE THROUGHOUT THE
DAY AND LAST WELL INTO THE NIGHT. IN GENERAL...WINDS WILL BE FROM
THE SOUTHEAST BUT RAPID CHANGES IN DIRECTION DUE TO TSTMS AND/OR
OUTFLOW BOUNDARIES FROM TSTMS CAN BE EXPECTED WITH STORMS NEAR THE
AIRFIELDS.
&&
.FGF WATCHES/WARNINGS/ADVISORIES...
ND...FLASH FLOOD WATCH THROUGH SUNDAY MORNING FOR NDZ006>008-014>016-
024-026>030-038-039-049-052>054.
MN...FLASH FLOOD WATCH THROUGH SUNDAY MORNING FOR MNZ001>005-007-008-
013>015-022-027-029-030-040.
&&
$$
UPDATE...JR
SHORT TERM...TG
LONG TERM...TG/HOPPES
AVIATION...SPEICHER
AREA FORECAST DISCUSSION
NWS GRAND FORKS ND
943 AM CDT THU JUN 20 2013
.UPDATE...
ISSUED AT 943 AM CDT THU JUN 20 2013
CONVECTIVE COMPLEX OVER NORTH CENTRAL ND HAS STARTED TO MOVE INTO
OUR NORTHWESTERN COUNTIES...AND THERE HAS BEEN SOME ADDITIONAL
DEVELOPMENT SOUTHWARD TOWARDS VALLEY CITY. THERE HAS ALSO BEEN
SOME STORMS FIRING AROUND THE THIEF RIVER FALLS TO BEMIDJI AREAS.
BUMPED UP POPS SIGNIFICANTLY ACROSS THE NORTHWEST AND NORTHEAST.
THERE SHOULD BE A BREAK IN THE CENTRAL CWA THROUGH MID DAY BEFORE
MORE ACTIVITY MOVES IN LATER THIS AFTERNOON. LOWERED TEMPS JUST A
TAD FOR MORE PRECIP AND CLOUDS THAN EXPECTED...BUT THINK THERE
SHOULD STILL GET ENOUGH HEATING TO GET INTO THE UPPER 70S TO MID
80S WITH GOOD INSTABILITY DEVELOPING BY AFTERNOON. WILL CONTINUE
WITH SEVERE MENTION INTO THE AFTERNOON AND EVENING AND WILL
MONITOR PREDICTED QPF AMOUNTS GIVEN THE RECENT HEAVY RAINS OVER
THE SOUTHERN CWA AND IF WE NEED ANY FLOOD WATCH PRODUCTS LATER ON.
UPDATE ISSUED AT 710 AM CDT THU JUN 20 2013
NOT MUCH CHANGE TO PREVIOUS THINKING. TWEAKED POPS AND WX
ACCORDING TO CURRENT CONDITIONS AND LATEST HRRR GUIDANCE FOR THE
MORNING HOURS. PORTIONS OF SARGENT AND RANSOM COUNTY LIKELY
RECEIVED UP TO 8 INCHES OF RAIN...AND MAJOR FLOODING ISSUES ARE
BEING REPORTED. REPORTS ARE JUST COMING INTO THE OFFICE...AND
THERE ARE STILL A LOT OF UNKNOWNS AT THIS POINT. THE SEVERE THREAT
FOR THE MORNING HOURS SHOULD REMAIN SOUTH OF THE FA...ALTHOUGH
THERE IS A SEVERE BOW JUST SOUTH OF THE FA THAT WE WILL NEED TO
MONITOR.
ACTIVITY ACROSS NORTH CENTRAL NORTH DAKOTA WILL CONTINUE TO
PROPAGATE TO THE NORTH. IT MAY CLIP OUR NORTHWESTERN FA...AND WILL
MONITOR. THIS ACTIVITY IS CURRENTLY NOT SEVERE.
THE SEVERE THREAT IS STILL ON TRACK FOR LATER THIS AFTERNOON AND
OVERNIGHT. FAIRLY CONFIDENT THAT THERE WILL BE A BREAK IN ACTIVITY
TODAY...WHICH WOULD ALLOW HEATING AND MOISTURE RETURN...LEADING TO
AN ELEVATED SEVERE THREAT.
&&
.SHORT TERM...(TODAY THROUGH FRIDAY)
ISSUED AT 330 AM CDT THU JUN 20 2013
MAIN CONCERN WILL BE SEVERE THUNDER AND HEAVY RAIN POTENTIAL THIS
AFTERNOON AND OVERNIGHT.
AREA OF THUNDERSTORMS CURRENTLY ONGOING ACROSS THE SOUTHERN FA
(AND BUILDING INTO THE WESTERN FA) WHERE WATER VAPOR IMAGERY
INDICATES AN UPPER WAVE AND THE RAP INDICATES 30-40 KNOT 850MB JET
INDUCED BY THIS UPPER WAVE. ANTICIPATE THIS ACTIVITY TO CONTINUE
INTO THE DAYLIGHT HOURS AND THEN DISSIPATE WITH SUBSIDENCE BEHIND
THE WAVE. SEVERE POTENTIAL IS VERY LOW CONSIDERING WEAK
INSTABILITY. THE MAIN THREAT WILL BE HEAVY RAIN WITH PWATS AROUND
1.5 INCHES AND SLOW STORM MOTIONS.
ANTICIPATE A BREAK IN THE ACTIVITY DURING THE MID-DAY HOURS WHICH
SHOULD ALLOW FOR SOME HEATING AND MOISTURE ADVECTION...WITH MLCAPE
VALUES AOA 2000 J/KG SOME AREAS. FORCING FOR REDEVELOPMENT SHOULD
COME WITH A POSSIBLE MCV FROM ACTIVITY TO THE WEST (ACROSS
NORTHERN MONTANA) AS WELL AS AN UPPER WAVE FROM THE SOUTHWEST THAT
SOME MODEL INDICATE. PREFER TO FOLLOW THE ECMWF FOR DEWPOINT
VALUES CONSIDERING LACK OF EVAPOTRANSPIRATION DUE TO LATE CROPS
THIS YEAR. THIS SOLUTION WOULD HAVE MLCAPE 2000-2500 J/KG INTO SE
NORTH DAKOTA BY 21Z...WITH DECREASING INSTABILITY TO THE NORTH
AND EAST (AND THE INSTABILITY AXIS INTO NORTH CENTRAL NORTH
DAKOTA). MOST LIKELY SCENARIO IS THAT THUNDER INITIATES ALONG THE
LOW LEVEL BOUNDARY/DRY LINE ACROSS CENTRAL NORTH DAKOTA...AND
EVENTUALLY BECOMES SOME SORT OF MCS THAT BUILDS INTO THE HIGHER
STABILITY (WHICH MOST LIKELY WILL BE TO THE SOUTH). THE MAIN
THREATS WILL LIKELY BE LARGE HAIL AND ESPECIALLY WIND GUSTS. A
TORNADO OR TWO IS ALSO POSSIBLE...ESPECIALLY INITIALLY. OTHER
MODELS ARE MORE ROBUST WITH DEWPOINTS VALUES (INTO THE LOW/MID
70S...AND WELL NORTH INTO THE FA)...WHICH LIKELY ACCOUNTS FOR THEM
WANTING TO MOVE THE MCS TO THE EAST INTO NORTHERN
MINNESOTA...OPPOSED TO THE ECMWF WHICH MOVES THIS FEATURE INTO
SOUTHERN MINNESOTA. HEAVY RAIN ALSO A THREAT WITH PWATS ABOVE 1.5
INCHES. NOT SURE EXACTLY WHERE THE HEAVIEST RAIN WILL OCCUR
TONIGHT...BUT A FLASH FLOOD WATCH MAY BE NEEDED ACROSS THE
SOUTHERN FA WHERE THE HEAVY RAIN IS CURRENTLY OCCURRING.
.LONG TERM...(FRIDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 330 AM CDT THU JUN 20 2013
FRIDAY-SATURDAY NIGHT...REGION WILL BE IN SOUTHWEST FLOW
ALOFT...AND CONVECTIVE CHANCES WILL HINGE ON TIMING OF SHORTWAVES
EJECTING FROM THE WESTERN TROUGH. FOLLOWING THE ECMWF FOR
TIMING...KEPT THE LIKELY POPS FOR FRIDAY EVENING INTO SATURDAY
MORNING...AND AGAIN FOR SATURDAY NIGHT. SEVERE STORMS AGAIN A
POSSIBILITY...AND DEPENDENT ON INSTABILITY VALUES. THE SOUTHERN FA
APPEARS TO HAVE THE BEST CHANCE FOR SEVERE STORMS. HEAVY RAIN ALSO
A POSSIBILITY...AND FUTURE SHIFTS MAY NEED TO CONSIDER FLOOD/FLASH
FLOOD WATCHES DEPENDING ON WHAT HAPPENS TODAY.
SUNDAY-WEDNESDAY...LONG WAVE TROUGH RE-ESTABLISHES FARTHER WEST
OVER THE EASTERN PACIFIC. A LONG WAVE RIDGE BUILDS OVER THE
CENTRAL US BY THE END OF THE PERIOD. GFS AND ECMWF ARE SIMILAR
TIMING WISE AT 84 HOURS BUT THE ECMWF BECOMES THE FASTER SOLUTION
FOR THE REST OF THE PERIOD. WILL USE A BLEND OF THE ECMWF AND GFS.
PRECIPITATION IS A LITTLE FASTER WITH TODAYS RUNS AND WILL BE SUED.
LITTLE CHANGE TO TEMPS THROUGH THE PERIOD COMPARED TO YESTERDAY
PACKAGE.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z FRIDAY MORNING)
ISSUED AT 710 AM CDT THU JUN 20 2013
THE MAIN CONCERN WILL BE INCREASING THUNDERSTORM CHANCES THIS
AFTERNOON AND OVERNIGHT. THUNDERSTORMS APPEAR LIKELY MOST
AREAS...AND ATTEMPTED TO INDICATE THE MOST LIKELY PERIOD OF
OCCURRENCE.
&&
.FGF WATCHES/WARNINGS/ADVISORIES...
ND...NONE.
MN...NONE.
&&
$$
UPDATE...JR
SHORT TERM...TG
LONG TERM...TG/HOPPES
AVIATION...TG
AREA FORECAST DISCUSSION
NWS GRAND FORKS ND
710 AM CDT THU JUN 20 2013
.UPDATE...
ISSUED AT 710 AM CDT THU JUN 20 2013
NOT MUCH CHANGE TO PREVIOUS THINKING. TWEAKED POPS AND WX
ACCORDING TO CURRENT CONDITIONS AND LATEST HRRR GUIDANCE FOR THE
MORNING HOURS. PORTIONS OF SARGENT AND RANSOM COUNTY LIKELY
RECEIVED UP TO 8 INCHES OF RAIN...AND MAJOR FLOODING ISSUES ARE
BEING REPORTED. REPORTS ARE JUST COMING INTO THE OFFICE...AND
THERE ARE STILL A LOT OF UNKNOWNS AT THIS POINT. THE SEVERE THREAT
FOR THE MORNING HOURS SHOULD REMAIN SOUTH OF THE FA...ALTHOUGH
THERE IS A SEVERE BOW JUST SOUTH OF THE FA THAT WE WILL NEED TO
MONITOR.
ACTIVITY ACROSS NORTH CENTRAL NORTH DAKOTA WILL CONTINUE TO
PROPAGATE TO THE NORTH. IT MAY CLIP OUR NORTHWESTERN FA...AND WILL
MONITOR. THIS ACTIVITY IS CURRENTLY NOT SEVERE.
THE SEVERE THREAT IS STILL ON TRACK FOR LATER THIS AFTERNOON AND
OVERNIGHT. FAIRLY CONFIDENT THAT THERE WILL BE A BREAK IN ACTIVITY
TODAY...WHICH WOULD ALLOW HEATING AND MOISTURE RETURN...LEADING TO
AN ELEVATED SEVERE THREAT.
&&
.SHORT TERM...(TODAY THROUGH FRIDAY)
ISSUED AT 330 AM CDT THU JUN 20 2013
MAIN CONCERN WILL BE SEVERE THUNDER AND HEAVY RAIN POTENTIAL THIS
AFTERNOON AND OVERNIGHT.
AREA OF THUNDERSTORMS CURRENTLY ONGOING ACROSS THE SOUTHERN FA
(AND BUILDING INTO THE WESTERN FA) WHERE WATER VAPOR IMAGERY
INDICATES AN UPPER WAVE AND THE RAP INDICATES 30-40 KNOT 850MB JET
INDUCED BY THIS UPPER WAVE. ANTICIPATE THIS ACTIVITY TO CONTINUE
INTO THE DAYLIGHT HOURS AND THEN DISSIPATE WITH SUBSIDENCE BEHIND
THE WAVE. SEVERE POTENTIAL IS VERY LOW CONSIDERING WEAK
INSTABILITY. THE MAIN THREAT WILL BE HEAVY RAIN WITH PWATS AROUND
1.5 INCHES AND SLOW STORM MOTIONS.
ANTICIPATE A BREAK IN THE ACTIVITY DURING THE MID-DAY HOURS WHICH
SHOULD ALLOW FOR SOME HEATING AND MOISTURE ADVECTION...WITH MLCAPE
VALUES AOA 2000 J/KG SOME AREAS. FORCING FOR REDEVELOPMENT SHOULD
COME WITH A POSSIBLE MCV FROM ACTIVITY TO THE WEST (ACROSS
NORTHERN MONTANA) AS WELL AS AN UPPER WAVE FROM THE SOUTHWEST THAT
SOME MODEL INDICATE. PREFER TO FOLLOW THE ECMWF FOR DEWPOINT
VALUES CONSIDERING LACK OF EVAPOTRANSPIRATION DUE TO LATE CROPS
THIS YEAR. THIS SOLUTION WOULD HAVE MLCAPE 2000-2500 J/KG INTO SE
NORTH DAKOTA BY 21Z...WITH DECREASING INSTABILITY TO THE NORTH
AND EAST (AND THE INSTABILITY AXIS INTO NORTH CENTRAL NORTH
DAKOTA). MOST LIKELY SCENARIO IS THAT THUNDER INITIATES ALONG THE
LOW LEVEL BOUNDARY/DRY LINE ACROSS CENTRAL NORTH DAKOTA...AND
EVENTUALLY BECOMES SOME SORT OF MCS THAT BUILDS INTO THE HIGHER
STABILITY (WHICH MOST LIKELY WILL BE TO THE SOUTH). THE MAIN
THREATS WILL LIKELY BE LARGE HAIL AND ESPECIALLY WIND GUSTS. A
TORNADO OR TWO IS ALSO POSSIBLE...ESPECIALLY INITIALLY. OTHER
MODELS ARE MORE ROBUST WITH DEWPOINTS VALUES (INTO THE LOW/MID
70S...AND WELL NORTH INTO THE FA)...WHICH LIKELY ACCOUNTS FOR THEM
WANTING TO MOVE THE MCS TO THE EAST INTO NORTHERN
MINNESOTA...OPPOSED TO THE ECMWF WHICH MOVES THIS FEATURE INTO
SOUTHERN MINNESOTA. HEAVY RAIN ALSO A THREAT WITH PWATS ABOVE 1.5
INCHES. NOT SURE EXACTLY WHERE THE HEAVIEST RAIN WILL OCCUR
TONIGHT...BUT A FLASH FLOOD WATCH MAY BE NEEDED ACROSS THE
SOUTHERN FA WHERE THE HEAVY RAIN IS CURRENTLY OCCURRING.
.LONG TERM...(FRIDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 330 AM CDT THU JUN 20 2013
FRIDAY-SATURDAY NIGHT...REGION WILL BE IN SOUTHWEST FLOW
ALOFT...AND CONVECTIVE CHANCES WILL HINGE ON TIMING OF SHORTWAVES
EJECTING FROM THE WESTERN TROUGH. FOLLOWING THE ECMWF FOR
TIMING...KEPT THE LIKELY POPS FOR FRIDAY EVENING INTO SATURDAY
MORNING...AND AGAIN FOR SATURDAY NIGHT. SEVERE STORMS AGAIN A
POSSIBILITY...AND DEPENDENT ON INSTABILITY VALUES. THE SOUTHERN FA
APPEARS TO HAVE THE BEST CHANCE FOR SEVERE STORMS. HEAVY RAIN ALSO
A POSSIBILITY...AND FUTURE SHIFTS MAY NEED TO CONSIDER FLOOD/FLASH
FLOOD WATCHES DEPENDING ON WHAT HAPPENS TODAY.
SUNDAY-WEDNESDAY...LONG WAVE TROUGH RE-ESTABLISHES FARTHER WEST
OVER THE EASTERN PACIFIC. A LONG WAVE RIDGE BUILDS OVER THE
CENTRAL US BY THE END OF THE PERIOD. GFS AND ECMWF ARE SIMILAR
TIMING WISE AT 84 HOURS BUT THE ECMWF BECOMES THE FASTER SOLUTION
FOR THE REST OF THE PERIOD. WILL USE A BLEND OF THE ECMWF AND GFS.
PRECIPITATION IS A LITTLE FASTER WITH TODAYS RUNS AND WILL BE SUED.
LITTLE CHANGE TO TEMPS THROUGH THE PERIOD COMPARED TO YESTERDAY
PACKAGE.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z FRIDAY MORNING)
ISSUED AT 710 AM CDT THU JUN 20 2013
THE MAIN CONCERN WILL BE INCREASING THUNDERSTORM CHANCES THIS
AFTERNOON AND OVERNIGHT. THUNDERSTORMS APPEAR LIKELY MOST
AREAS...AND ATTEMPTED TO INDICATE THE MOST LIKELY PERIOD OF
OCCURRENCE.
&&
.FGF WATCHES/WARNINGS/ADVISORIES...
ND...NONE.
MN...NONE.
&&
$$
UPDATE...TG
SHORT TERM...TG
LONG TERM...TG/HOPPES
AVIATION...TG
AREA FORECAST DISCUSSION
NWS GRAND FORKS ND
358 AM CDT THU JUN 20 2013
.SHORT TERM...(TODAY THROUGH FRIDAY)
ISSUED AT 330 AM CDT THU JUN 20 2013
MAIN CONCERN WILL BE SEVERE THUNDER AND HEAVY RAIN POTENTIAL THIS
AFTERNOON AND OVERNIGHT.
AREA OF THUNDERSTORMS CURRENTLY ONGOING ACROSS THE SOUTHERN FA
(AND BUILDING INTO THE WESTERN FA) WHERE WATER VAPOR IMAGERY
INDICATES AN UPPER WAVE AND THE RAP INDICATES 30-40 KNOT 850MB JET
INDUCED BY THIS UPPER WAVE. ANTICIPATE THIS ACTIVITY TO CONTINUE
INTO THE DAYLIGHT HOURS AND THEN DISSIPATE WITH SUBSIDENCE BEHIND
THE WAVE. SEVERE POTENTIAL IS VERY LOW CONSIDERING WEAK
INSTABILITY. THE MAIN THREAT WILL BE HEAVY RAIN WITH PWATS AROUND
1.5 INCHES AND SLOW STORM MOTIONS.
ANTICIPATE A BREAK IN THE ACTIVITY DURING THE MID-DAY HOURS WHICH
SHOULD ALLOW FOR SOME HEATING AND MOISTURE ADVECTION...WITH MLCAPE
VALUES AOA 2000 J/KG SOME AREAS. FORCING FOR REDEVELOPMENT SHOULD
COME WITH A POSSIBLE MCV FROM ACTIVITY TO THE WEST (ACROSS
NORTHERN MONTANA) AS WELL AS AN UPPER WAVE FROM THE SOUTHWEST THAT
SOME MODEL INDICATE. PREFER TO FOLLOW THE ECMWF FOR DEWPOINT
VALUES CONSIDERING LACK OF EVAPOTRANSPIRATION DUE TO LATE CROPS
THIS YEAR. THIS SOLUTION WOULD HAVE MLCAPE 2000-2500 J/KG INTO SE
NORTH DAKOTA BY 21Z...WITH DECREASING INSTABILITY TO THE NORTH
AND EAST (AND THE INSTABILITY AXIS INTO NORTH CENTRAL NORTH
DAKOTA). MOST LIKELY SCENARIO IS THAT THUNDER INITIATES ALONG THE
LOW LEVEL BOUNDARY/DRY LINE ACROSS CENTRAL NORTH DAKOTA...AND
EVENTUALLY BECOMES SOME SORT OF MCS THAT BUILDS INTO THE HIGHER
STABILITY (WHICH MOST LIKELY WILL BE TO THE SOUTH). THE MAIN
THREATS WILL LIKELY BE LARGE HAIL AND ESPECIALLY WIND GUSTS. A
TORNADO OR TWO IS ALSO POSSIBLE...ESPECIALLY INITIALLY. OTHER
MODELS ARE MORE ROBUST WITH DEWPOINTS VALUES (INTO THE LOW/MID
70S...AND WELL NORTH INTO THE FA)...WHICH LIKELY ACCOUNTS FOR THEM
WANTING TO MOVE THE MCS TO THE EAST INTO NORTHERN
MINNESOTA...OPPOSED TO THE ECMWF WHICH MOVES THIS FEATURE INTO
SOUTHERN MINNESOTA. HEAVY RAIN ALSO A THREAT WITH PWATS ABOVE 1.5
INCHES. NOT SURE EXACTLY WHERE THE HEAVIEST RAIN WILL OCCUR
TONIGHT...BUT A FLASH FLOOD WATCH MAY BE NEEDED ACROSS THE
SOUTHERN FA WHERE THE HEAVY RAIN IS CURRENTLY OCCURRING.
.LONG TERM...(FRIDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 330 AM CDT THU JUN 20 2013
FRIDAY-SATURDAY NIGHT...REGION WILL BE IN SOUTHWEST FLOW
ALOFT...AND CONVECTIVE CHANCES WILL HINGE ON TIMING OF SHORTWAVES
EJECTING FROM THE WESTERN TROUGH. FOLLOWING THE ECMWF FOR
TIMING...KEPT THE LIKELY POPS FOR FRIDAY EVENING INTO SATURDAY
MORNING...AND AGAIN FOR SATURDAY NIGHT. SEVERE STORMS AGAIN A
POSSIBILITY...AND DEPENDENT ON INSTABILITY VALUES. THE SOUTHERN FA
APPEARS TO HAVE THE BEST CHANCE FOR SEVERE STORMS. HEAVY RAIN ALSO
A POSSIBILITY...AND FUTURE SHIFTS MAY NEED TO CONSIDER FLOOD/FLASH
FLOOD WATCHES DEPENDING ON WHAT HAPPENS TODAY.
SUNDAY-WEDNESDAY...LONG WAVE TROUGH RE-ESTABLISHES FARTHER WEST
OVER THE EASTERN PACIFIC. A LONG WAVE RIDGE BUILDS OVER THE
CENTRAL US BY THE END OF THE PERIOD. GFS AND ECMWF ARE SIMILAR
TIMING WISE AT 84 HOURS BUT THE ECMWF BECOMES THE FASTER SOLUTION
FOR THE REST OF THE PERIOD. WILL USE A BLEND OF THE ECMWF AND GFS.
PRECIPITATION IS A LITTLE FASTER WITH TODAYS RUNS AND WILL BE SUED.
LITTLE CHANGE TO TEMPS THROUGH THE PERIOD COMPARED TO YESTERDAY
PACKAGE.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z THURSDAY NIGHT)
ISSUED AT 1125 PM CDT WED JUN 19 2013
THE CHANCES FOR SHOWERS AND THUNDERSTORMS WILL INCREASE FROM WEST
TO EAST OVERNIGHT AND THURSDAY. HAVE STARTED TO MENTION SOME
CONVECTION...ALTHOUGH TIMING REMAINS TOUGH. FOR NOW HAVE KEPT ALL
CIGS IN VFR CATEGORY...AND WILL CONTINUE TO REVISE FORECAST ONCE
TIMING AND AREAL COVERAGE BECOMES A BIT MORE CERTAIN.
&&
.FGF WATCHES/WARNINGS/ADVISORIES...
ND...NONE.
MN...NONE.
&&
$$
SHORT TERM...TG
LONG TERM...TG/HOPPES
AVIATION...DK
AREA FORECAST DISCUSSION
NWS CHARLESTON WV
245 PM EDT THU JUN 20 2013
.SYNOPSIS...
HIGH PRESSURE AT THE SURFACE AND ALOFT...TOGETHER WITH WEAK FLOW
REMAINS IN CONTROL THROUGH THE WEEKEND. HOWEVER...MOUNTAIN
CONVECTION POSSIBLE THROUGH THE WEEKEND.
&&
.NEAR TERM /THROUGH FRIDAY/...
STILL ON TRACK FOR A FEW AFTN SHRA/TSRA TO DEVELOP ON THE RIDGES
ON WEAK SE FLOW...AIDED BY ELEVATED HEAT SRC. LATEST HRRR SEEMS TO
HAVE A GOOD HANDLE ON THIS AND USED IT TO FINE TUNE POPS WITH
BULLSEYE CHC ACROSS RIDGES IN CENTRAL MTNS ACROSS EXTREME E
FAYETTE AND NICHOLAS CO AND INTO POCAHONTAS. WITH SCHC POPS
ACROSS REMAINDER OF RIDGES DOWN TO SW VA. PEAK COVERAGE ARND
21Z...WANING BY 00Z. ELSEWHERE LACK OF A FORCING MECHANISM AND CAP
KEEPS THINGS DRY. DID ALLOW FOR SOME SCHC POPS ADJ OF THE RIDGES
IN CASE THINGS TRY TO SLIDE OFF RIDGES. OVERALL VERY WEAK FLOW
SHOULD MEAN MAINLY RIDGE TOP HUGGERS THOUGH. WILL HAVE TO WATCH FOR
VERY ISO HVY RAINFALL AMNTS FROM NEAR STATIONARY
MOVEMENT...ALTHOUGH PWATS ARE BLO AND INCH.
MDLS SHOW QUITE A BIT OF H85 MOISTURE LINGERING OVERNIGHT ACROSS
THE MTNS WITHS SOME H925 MOISTURE ALONG E SLOPES. THINK MOST OF
THIS DISSIPATES WITH LOSS OF HEATING...SAVE FOR THE E SLOPES LLVL
MOISTURE. SHOULD BE ANOTHER GOOD FG NIGHT FOR RVR
VALLEYS...ESPECIALLY ACROSS KANAWHA...TUG FORK...GUYANDOTTE AND
OF COURSE TYGART.
MORNING FG BURNS OF BY 13Z WITH MORE OF THE SAME FOR AFTN AS TDY.
HAVE MAINLY MTN CU FIELDS WHERE LOW CHC POPS WERE INSERTED FOR
LATE AFTN SHRA/TSRA.
FELT GUIDANCE WAS A COUPLE DEGREES TOO WARM FOR TOMORROW GIVEN
RECENT RAINS. STILL HAVE MID/UPR 80S OUTSIDE OF THE MTNS WITH 70S
TO LOW 80S IN THE HIGH COUNTRY.
&&
.SHORT TERM /FRIDAY NIGHT THROUGH SUNDAY/...
MAIN MID/UPPER LEVEL FLOW TO REMAIN TO THE NORTH DURING THE SHORT
TERM...WITH ANY APPRECIABLE FORCING STAYING OUT OF THE CWA. NOT A
LOT OF CHANGES TO THIS PORTION OF THE FORECAST...WITH PEAK HEATING
BRINGING THE POTENTIAL FOR A FEW MOUNTAIN SHOWER/STORMS...AND LESS
POTENTIAL OVER THE LOWLAND AREAS. STILL DEALING WITH A CAP AROUND
725MB...AND NOT A LOT TO WORK WITH IN TERMS OF AVAILABLE MOISTURE.
AGAIN...CONVECTIVE TEMPERATURE SHOULD BE REACHED...AND CANNOT RULE
OUT TOWERING CUMULUS COMPLETELY.
KEEPING THE TEMPERATURES IN THE UPPER 80S TO AROUND 90 DEGREES FOR
THE LOWLANDS...WHILE KNOCKING A FEW OFF THE PACE FOR THE HIGHER
ELEVATIONS.
&&
.LONG TERM /SUNDAY NIGHT THROUGH THURSDAY/...
PATTERN REMAINS ON THE WARM SIDE WITH DAYTIME HEATING CHANCES FOR
SHOWERS/STORMS CONTINUING. LONG WAVE PATTERN WILL AMPLIFY MID WEEK
TOWARDS THE END OF NEXT WEEK WITH A STRONG RIDGE/HEAT WAVE EXPECTED
OVER THE INTERMOUNTAIN WEST...AND A TROUGH DIGGING INTO THE GREAT
LAKES BY FRIDAY. CPC BRINGS IN HIGHER CHANCES FOR A WETTER TREND FOR
THE END OF NEXT WEEK GIVEN THIS RIDGE/TROUGH SYSTEM. UNTIL THEN
PRECIPITATION WILL BE HIT OR MISS...WITH BETTER CHANCES IN THE
ELEVATED HEAT SOURCE AREAS TO THE EAST. TEMPERATURES REMAIN ABOVE
NORMAL.
&&
.AVIATION /19Z THURSDAY THROUGH TUESDAY/...
VFR CONDITIONS THROUGH 00Z WITH SCT TO BKN 4 TO 6 KFT CU ACROSS
THE MTNS. WEAK SE LLVL FLOW WILL AID IN MAINLY ISOLATED SHRA/TSRA
ON THE RIDGES LATE THIS AFTN. PUT A VCSH IN KBKW FOR A FEW HRS.
MUCH OF CU DISSIPATES AFTER SUNSET. SOME MOISTURE TRIES TO LINGER
OVERNIGHT ACROSS THE MTNS WHICH MAY LEAVE SOME A FEW CLDS ARND.
LOW STRATUS MAY ALSO TRY TO DEVELOP LATE ON SE FLOW ACROSS E
SLOPES. HAVE HELD THIS OUT OF KBKW TAF FOR NOW.
OTHERWISE...ANOTHER RVR VALLEY FG NIGHT. TIMED ABOUT AN HR LATER
THAN LAST NIGHT. HAVE LIFR FG FOR KPKB...KEKN...AND KCRW OVERNIGHT
WITH SOME IFR FG ACROSS KHTS AND MVFR KBKW. THINK KCKB ESCAPES THE
FG.
MORNING FG LIFTS BY 13Z FOR A RETURN TO VFR CONDITIONS. SAME STORY
HOLDS FOR TOM AND TDY WITH MUCH OF CU ACROSS MTNS WITH SMALL CHC
FOR LATE AFTN SHRA/TSRA.
CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 06Z WEDNESDAY...
FORECAST CONFIDENCE...MEDIUM.
FORECAST CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 18Z FRIDAY...
FORECAST CONFIDENCE: TIMING OF DENSITY AND DURATION OF REDUCED VIS
AFTER 06Z MAY VARY.
EXPERIMENTAL TABLE OF FLIGHT CATEGORY OBJECTIVELY SHOWS CONSISTENCY
OF WFO FORECAST TO AVAILABLE MODEL INFORMATION:
H = HIGH: TAF CONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.
M = MEDIUM: TAF HAS VARYING LEVEL OF CONSISTENCY WITH MODELS.
L = LOW: TAF INCONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.
UTC 1HRLY 18 19 20 21 22 23 00 01 02 03 04 05
EDT 1HRLY 14 15 16 17 18 19 20 21 22 23 00 01
CRW CONSISTENCY H H H H H H H H H H H H
HTS CONSISTENCY H H H H H H H H H H H H
BKW CONSISTENCY H H H H H H H H H H H H
EKN CONSISTENCY H H H H H H H H H H H H
PKB CONSISTENCY H H H H H H H H H H H H
CKB CONSISTENCY H H H H H H H H H H H H
AFTER 18Z FRIDAY...
IFR/LIFR IN NOCTURNAL FOG LESS WIDESPREAD...BUT STILL POSSIBLE 09Z
TO 12Z SATURDAY.
&&
.RLX WATCHES/WARNINGS/ADVISORIES...
WV...NONE.
OH...NONE.
KY...NONE.
VA...NONE.
&&
$$
SYNOPSIS...30/26
NEAR TERM...30
SHORT TERM...26
LONG TERM...26
AVIATION...30
AREA FORECAST DISCUSSION
NWS CHARLESTON WV
223 PM EDT THU JUN 20 2013
.SYNOPSIS...
HIGH PRESSURE AT THE SURFACE AND ALOFT...TOGETHER WITH WEAK FLOW
REMAINS IN CONTROL THROUGH THE WEEKEND. HOWEVER...MOUNTAIN
CONVECTION POSSIBLE THROUGH THE WEEKEND.
&&
.NEAR TERM /THROUGH FRIDAY/...
STILL ON TRACK FOR A FEW AFTN SHRA/TSRA TO DEVELOP ON THE RIDGES
ON WEAK SE FLOW...AIDED BY ELEVATED HEAT SRC. LATEST HRRR SEEMS TO
HAVE A GOOD HANDLE ON THIS AND USED IT TO FINE TUNE POPS WITH
BULLSEYE CHC ACROSS RIDGES IN CENTRAL MTNS ACROSS EXTREME E
FAYETTE AND NICHOLAS CO AND INTO POCAHONTAS. WITH SCHC POPS
ACROSS REMAINDER OF RIDGES DOWN TO SW VA. PEAK COVERAGE ARND
21Z...WANING BY 00Z. ELSEWHERE LACK OF A FORCING MECHANISM AND CAP
KEEPS THINGS DRY. DID ALLOW FOR SOME SCHC POPS ADJ OF THE RIDGES
IN CASE THINGS TRY TO SLIDE OFF RIDGES. OVERALL VERY WEAK FLOW
SHOULD MEAN MAINLY RIDGETOP HUGGERS THOUGH. WILL HAVE TO WATCH FOR
VERY ISO HVY RAINFALL AMNTS FROM NEAR STATIONARY
MOVEMENT...ALTHOUGH PWATS ARE BLO AND INCH.
MDLS SHOW QUITE A BIT OF H85 MOISTURE LINGERING OVERNIGHT ACROSS
THE MTNS WITHS SOME H925 MOISTURE ALONG E SLOPES. THINK MOST OF
THIS DISSIPATES WITH LOSS OF HEATING...SAVE FOR THE E SLOPES LLVL
MOISTURE. SHOULD BE ANOTHER GOOD FG NIGHT FOR RVR
VALLEYS...ESPECIALLY ACROSS KANAWHA...TUG FORK...GUYANDOTTE AND
OF COURSE TYGART.
MORNING FG BURNS OF BY 13Z WITH MORE OF THE SAME FOR AFTN AS TDY.
HAVE MAINLY MTN CU FIELDS WHERE LOW CHC POPS WERE INSERTED FOR
LATE AFTN SHRA/TSRA.
FELT GUIDANCE WAS A COUPLE DEGREES TOO WARM FOR TOMORROW GIVEN
RECENT RAINS. STILL HAVE MID/UPR 80S OUTSIDE OF THE MTNS WITH 70S
TO LOW 80S IN THE HIGH COUNTRY.
&&
.SHORT TERM /FRIDAY NIGHT THROUGH SATURDAY NIGHT/...
ONLY MINOR CHANGES MADE TO ONGOING FORECAST FOR THIS PERIOD WITH
UPPER RIDGE BERMUDA HIGH BUILDING WESTWARD INTO THE AREA RESULTING
IN WEAK FLOW ALOFT. INHERITED MAX TEMPS BOTH DAYS IN THE UPPER 80S
FOR LOWLANDS...AND PERHAPS A DEGREE OR TWO WARMER SAT VERSUS
FRI...STILL LOOK GOOD. DESPITE WEAK LARGE SCALE FORCING FOR
SUBSIDENCE OVER THE AREA...DID ELECT TO NUDGE POPS IN THE EASTERN
HIGH TERRAIN UP JUST A BIT INTO MID-CHANCE BASED ON GOOD MODEL
AGREEMENT WITH REGARD TO SFC CONVERGENCE ON THE RIDGETOPS AS WELL AS
GOOD LLVL MOISTURE ON SE FLOW. NOT EXPECTING MUCH WITH REGARD TO
STRONG STORM POTENTIAL WITH A CAP ABOVE 700MB...BUT WITH TALL EL/S
ALONG WITH GOOD THETA-E LAPSE RATES AND VERY SLOW STORM MOTIONS IT/S
POSSIBLE THAT A FEW STRONGER STORMS COULD PRODUCE SOME BRIEF HEAVY
RAINFALL AND GUSTY WINDS. ESSENTIALLY THE SAME SETUP FOR SATURDAY AS
WELL...BUT WITH LESS MOISTURE TO WORK WITH. WILL KEEP INHERITED
SLIGHT CHANCE POPS AREA-WIDE SAT BASED ON CONVECTIVE TEMPERATURE
ALONE...BUT WILL LIMIT THIS POTENTIAL TO AFTER 18Z FOR A FEW HOURS
WITH MAX DAYTIME HEATING. LESS MOISTURE AND STRENGTHENING STABLE
LAYER ABOVE 700MB WILL KEEP POPS IN THE EASTERN MOUNTAINS ONLY AT
LOW CHANCE AS WELL...WHICH PREV FORECAST HAD A GOOD HANDLE ON. MOST
OF THIS ACTIVITY SHOULD REMAIN SHOWERS HOWEVER WITH AFOREMENTIONED
STABLE LAYER LIMITING UPDRAFT STRENGTH AND PWATS NOT QUITE REACHING
1.00IN.
&&
.LONG TERM /SUNDAY THROUGH THURSDAY/...
SURFACE HIGH PRESSURE WILL REMAIN CENTERED ACROSS THE SOUTHEAST
STATES...WITH A RIDGE EXTENDING NORTH INTO WEST VIRGINIA.
SOUTHERLY WINDS WILL RESULT IN DEW POINTS INCREASING TO THE UPPER
60S AND LOWER 70S. AS A RESULT...ISOLATED TO SCATTERED SHOWERS AND
THUNDERSTORM WILL BE A POSSIBILITY...MAINLY DURING THE AFTERNOON AND
EVENING HOURS.
AN UPPER LEVEL TROF AND AN ASSOCIATED COLD FRONT WILL APPROACH FROM
THE WEST LATE IN THE PERIOD...RESULTING IN BETTER CHANCES FOR
SHOWERS AND STORMS. THE BEST CHANCE OF GETTING WET WILL CONTINUE TO
BE DURING THE AFTERNOON AND EVENING HOURS.
EXPECT DAYTIME TEMPERATURES TO GENERALLY BE 5 OR MORE DEGREES
ABOVE NORMAL DURING THE PERIOD.
&&
.AVIATION /18Z THURSDAY THROUGH TUESDAY/...
VFR CONDITIONS THROUGH 00Z WITH SCT TO BKN 4 TO 6 KFT CU ACROSS
THE MTNS. WEAK SE LLVL FLOW WILL AID IN MAINLY ISOLATED SHRA/TSRA
ON THE RIDGES LATE THIS AFTN. PUT A VCSH IN KBKW FOR A FEW HRS.
MUCH OF CU DISSIPATES AFTER SUNSET. SOME MOISTURE TRIES TO LINGER
OVERNIGHT ACROSS THE MTNS WHICH MAY LEAVE SOME A FEW CLDS ARND.
LOW STRATUS MAY ALSO TRY TO DEVELOP LATE ON SE FLOW ACROSS E
SLOPES. HAVE HELD THIS OUT OF KBKW TAF FOR NOW.
OTHERWISE...ANOTHER RVR VALLEY FG NIGHT. TIMED ABOUT AN HR LATER
THAN LAST NIGHT. HAVE LIFR FG FOR KPKB...KEKN...AND KCRW OVERNIGHT
WITH SOME IFR FG ACROSS KHTS AND MVFR KBKW. THINK KCKB ESCAPES THE
FG.
MORNING FG LIFTS BY 13Z FOR A RETURN TO VFR CONDITIONS. SAME STORY
HOLDS FOR TOM AND TDY WITH MUCH OF CU ACROSS MTNS WITH SMALL CHC
FOR LATE AFTN SHRA/TSRA.
CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 06Z WEDNESDAY...
FORECAST CONFIDENCE...MEDIUM.
FORECAST CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 18Z FRIDAY...
FORECAST CONFIDENCE: TIMING OF DENSITY AND DURATION OF REDUCED VIS
AFTER 06Z MAY VARY.
EXPERIMENTAL TABLE OF FLIGHT CATEGORY OBJECTIVELY SHOWS CONSISTENCY
OF WFO FORECAST TO AVAILABLE MODEL INFORMATION:
H = HIGH: TAF CONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.
M = MEDIUM: TAF HAS VARYING LEVEL OF CONSISTENCY WITH MODELS.
L = LOW: TAF INCONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.
UTC 1HRLY 18 19 20 21 22 23 00 01 02 03 04 05
EDT 1HRLY 14 15 16 17 18 19 20 21 22 23 00 01
CRW CONSISTENCY H H H H H H H H H H H H
HTS CONSISTENCY H H H H H H H H H H H H
BKW CONSISTENCY H H H H H H H H H H H H
EKN CONSISTENCY H H H H H H H H H H H H
PKB CONSISTENCY H H H H H H H H H H H H
CKB CONSISTENCY H H H H H H H H H H H H
AFTER 18Z FRIDAY...
IFR/LIFR IN NOCTURNAL FOG LESS WIDESPREAD...BUT STILL POSSIBLE 09Z
TO 12Z SATURDAY.
&&
.RLX WATCHES/WARNINGS/ADVISORIES...
WV...NONE.
OH...NONE.
KY...NONE.
VA...NONE.
&&
$$
SYNOPSIS...30/26
NEAR TERM...30
SHORT TERM...50
LONG TERM...JSH
AVIATION...30
AREA FORECAST DISCUSSION
NWS CHARLESTON WV
1046 AM EDT THU JUN 20 2013
.SYNOPSIS...
HIGH PRESSURE AT THE SURFACE AND ALOFT...TOGETHER WITH WEAK FLOW
REMAINS IN CONTROL THROUGH THE WEEKEND. HOWEVER...MOUNTAIN
CONVECTION POSSIBLE THIS AFTERNOON AND FRIDAY AFTERNOON.
&&
.NEAR TERM /THROUGH TONIGHT/...
1045 AM MESOSCALE UPDATE...
LOW STRATUS STUBBORN TO SCT OUT THIS MORNING ACROSS E SLOPES OF
SE WV PLATEAU. 1430Z SATELLITE ALREADY SHOWING ABUNDANCE OF CU
ALONG AND E OF I79. EXPECT THIS TO EXPAND TO INCLUDE MUCH OF S WV
WITH JUST A FEW CLDS ACROSS SE OH AND NE KY. TWEAKED SKY GRIDS
WITH THIS IN MIND...HITTING MTNS WITH MORE CLDS THAN PREV FCST.
STILL ON TRACK FOR SOME AFTN SHRA/TSRA TO DEVELOP ON THE RIDGES ON
WEAK SE FLOW...AIDED BY ELEVATED HEAT SRC. LATEST HRRR SEEMS TO
HAVE A GOOD HANDLE ON THIS AND USED IT TO FINE TUNE POPS WITH HIGH
CHC ACROSS RIDGES IN CENTRAL MTNS ACROSS EXTREME E FAYETTE AND
NICHOLAS CO. WITH SOMEWHAT LOWER POPS ACROSS REMAINDER OF RIDGES
DOWN TO SW VA...ALBEIT STILL IN CHC CATEGORY. PEAK COVERAGE ARND
21Z...WANING BY 00Z. ELSEWHERE LACK OF A FORCING MECHANISM AND CAP
KEEPS THINGS DRY. DID ALLOW FOR SOME SCHC POPS ADJ OF THE RIDGES
TO W IN CASE THINGS TRY TO SLIDE OFF RIDGES. OVERALL VERY WEAK
FLOW SHOULD MEAN MAINLY RIDGETOP HUGGERS THOUGH. WILL HAVE TO
WATCH FOR VERY ISO HVY RAINFALL AMNTS FROM NEAR STATIONARY
MOVEMENT...ALTHOUGH PWATS ARE BLO AND INCH.
PREVIOUS DISCUSSION BELOW...
THE INFLUENCE OF A BROAD SFC HIGH PRESSURE PROVIDES MOSTLY CLEAR
SKIES AND WARM TEMPERATURES TODAY. AN UPPER LEVEL RIDGE MOVE
OVERHEAD CONTINUING DRY CONDITIONS THROUGH THE WEEKEND.
PATCHY FOG DURING THE PREDAWNS HOURS POSSIBLE DURING THE NEXT
COUPLE OF DAYS...MAINLY ALONG THE RIVER VALLEYS.
RAISED POPS TO CHANCES DURING THE AFTERNOON HOURS OVER ELEVATIONS
EQUAL AND HIGHER THAN 3 KFT. ANY CONVECTION AND CLOUDS SHOULD
DISSIPATE JUST AFTERNOON SUNSET.
MAINLY WENT WITH A BLEND OF BIAS CORRECTED MAV AND MET THROUGH THE
PERIOD.
&&
.SHORT TERM /FRIDAY THROUGH SATURDAY NIGHT/...
ONLY MINOR CHANGES MADE TO ONGOING FORECAST FOR THIS PERIOD WITH
UPPER RIDGE BERMUDA HIGH BUILDING WESTWARD INTO THE AREA RESULTING
IN WEAK FLOW ALOFT. INHERITED MAX TEMPS BOTH DAYS IN THE UPPER 80S
FOR LOWLANDS...AND PERHAPS A DEGREE OR TWO WARMER SAT VERSUS
FRI...STILL LOOK GOOD. DESPITE WEAK LARGE SCALE FORCING FOR
SUBSIDENCE OVER THE AREA...DID ELECT TO NUDGE POPS IN THE EASTERN
HIGH TERRAIN UP JUST A BIT INTO MID-CHANCE BASED ON GOOD MODEL
AGREEMENT WITH REGARD TO SFC CONVERGENCE ON THE RIDGETOPS AS WELL AS
GOOD LLVL MOISTURE ON SE FLOW. NOT EXPECTING MUCH WITH REGARD TO
STRONG STORM POTENTIAL WITH A CAP ABOVE 700MB...BUT WITH TALL EL/S
ALONG WITH GOOD THETA-E LAPSE RATES AND VERY SLOW STORM MOTIONS IT/S
POSSIBLE THAT A FEW STRONGER STORMS COULD PRODUCE SOME BRIEF HEAVY
RAINFALL AND GUSTY WINDS. ESSENTIALLY THE SAME SETUP FOR SATURDAY AS
WELL...BUT WITH LESS MOISTURE TO WORK WITH. WILL KEEP INHERITED
SLIGHT CHANCE POPS AREA-WIDE SAT BASED ON CONVECTIVE TEMPERATURE
ALONE...BUT WILL LIMIT THIS POTENTIAL TO AFTER 18Z FOR A FEW HOURS
WITH MAX DAYTIME HEATING. LESS MOISTURE AND STRENGTHENING STABLE
LAYER ABOVE 700MB WILL KEEP POPS IN THE EASTERN MOUNTAINS ONLY AT
LOW CHANCE AS WELL...WHICH PREV FORECAST HAD A GOOD HANDLE ON. MOST
OF THIS ACTIVITY SHOULD REMAIN SHOWERS HOWEVER WITH AFOREMENTIONED
STABLE LAYER LIMITING UPDRAFT STRENGTH AND PWATS NOT QUITE REACHING
1.00IN.
&&
.LONG TERM /SUNDAY THROUGH WEDNESDAY/...
SURFACE HIGH PRESSURE WILL REMAIN CENTERED ACROSS THE SOUTHEAST
STATES...WITH A RIDGE EXTENDING NORTH INTO WEST VIRGINIA.
SOUTHERLY WINDS WILL RESULT IN DEW POINTS INCREASING TO THE UPPER
60S AND LOWER 70S. AS A RESULT...ISOLATED TO SCATTERED SHOWERS AND
THUNDERSTORM WILL BE A POSSIBILITY...MAINLY DURING THE AFTERNOON AND
EVENING HOURS.
AN UPPER LEVEL TROF AND AN ASSOCIATED COLD FRONT WILL APPROACH FROM
THE WEST LATE IN THE PERIOD...RESULTING IN BETTER CHANCES FOR
SHOWERS AND STORMS. THE BEST CHANCE OF GETTING WET WILL CONTINUE TO
BE DURING THE AFTERNOON AND EVENING HOURS.
EXPECT DAYTIME TEMPERATURES TO GENERALLY BE 5 OR MORE DEGREES
ABOVE NORMAL DURING THE PERIOD.
&&
.AVIATION /15Z THURSDAY THROUGH MONDAY/...
IFR/LIFR FOG WILL CONTINUE ALONG RIVER VALLEYS...ESPECIALLY
CRW...PKB...EKN...AND HTS THROUGH AT LEAST 13Z. CONDITIONS WILL
QUICKLY IMPROVE AFTER 13-14Z...EXCEPT FOR MVFR CEILINGS OVER
EASTERN MOUNTAINS INCLUDING BKW THROUGH 16Z.
MOSTLY CLEAR SKIES EXPECTED ACROSS LOWLAND SITES BY NOON. LOW
LEVEL CU COULD DEVELOP WITH AFTERNOON HEATING AND AVAILABLE LOW
LEVEL MOISTURE. HOWEVER...CONDITIONS WILL PREVAIL VFR FOR THE REST
OF THURSDAY.
CALM FLOW AND CLEAR SKIES COULD RESULT IN ANOTHER FOGGY NIGHT
TONIGHT INTO FRIDAY MORNING.
THE WEAK SE FLOW COULD FORM SOME SLOW MOVING AND MAINLY ISOLATED
CELLS 18Z THURSDAY TO 00Z FRIDAY INCLUDING THE KBKW VCNTY.
CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 06Z WEDNESDAY...
FORECAST CONFIDENCE...MEDIUM.
FORECAST CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 12Z FRIDAY...
FORECAST CONFIDENCE: TIMING OF DENSITY AND DURATION OF REDUCED VIS
AND/OR LOW STRATUS AFTER 06Z THU MAY VARY.
EXPERIMENTAL TABLE OF FLIGHT CATEGORY OBJECTIVELY SHOWS CONSISTENCY
OF WFO FORECAST TO AVAILABLE MODEL INFORMATION:
H = HIGH: TAF CONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.
M = MEDIUM: TAF HAS VARYING LEVEL OF CONSISTENCY WITH MODELS.
L = LOW: TAF INCONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.
UTC 1HRLY 14 15 16 17 18 19 20 21 22 23 00 01
EDT 1HRLY 10 11 12 13 14 15 16 17 18 19 20 21
CRW CONSISTENCY H H H H H H H H H H H H
HTS CONSISTENCY H H H H H H H H H H H H
BKW CONSISTENCY H H H H H H H H H H H H
EKN CONSISTENCY H H H H H H H H H H H H
PKB CONSISTENCY H H H H H H H H H H H H
CKB CONSISTENCY H H H H H H H H H H H H
AFTER 12Z FRIDAY...
IFR/LIFR IN NOCTURNAL FOG LESS WIDESPREAD...BUT STILL POSSIBLE 09Z
TO 12Z FRIDAY.
&&
.RLX WATCHES/WARNINGS/ADVISORIES...
WV...NONE.
OH...NONE.
KY...NONE.
VA...NONE.
&&
$$
SYNOPSIS...ARJ/50
NEAR TERM...30/ARJ
SHORT TERM...50
LONG TERM...JSH
AVIATION...ARJ
AREA FORECAST DISCUSSION FOR WESTERN SD AND NORTHEASTERN WY
NWS RAPID CITY SD
1128 AM MDT THU JUN 20 2013
.SHORT TERM...TODAY THROUGH FRIDAY NIGHT
ISSUED AT 335 AM MDT THU JUN 20 2013
CURRENT SURFACE ANALYSIS SHOWS LOW PRESSURE OVER NORTHWESTERN
SD...WITH COLD FRONT STRETCHING SOUTH-SOUTHWESTWARD ACROSS THE
BLACK HILLS INTO EASTERN WY. UPPER LEVEL ANALYSIS HAS LOW OVER THE
PACIFIC NW...WITH SOUTHWESTERLY FLOW AHEAD OF IT ACROSS THE
ROCKIES AND NORTHERN PLAINS. REGIONAL RADARS SHOW A LINE OF STRONG
TO SEVERE STORMS OVER FAR NORTHEASTERN MT INTO WESTERN ND...WITH
OTHER SHOWER AND THUNDERSTORM ACTIVITY FURTHER SOUTH ACROSS
WESTERN SD INTO WESTERN NEB. A COUPLE OF STORMS ACROSS OUR AREA
HAS BEEN ON THE STRONG SIDE WITH GUSTY WINDS AND SMALL HAIL. TEMPS
ARE VERY WARM AHEAD OF THE FRONT...WITH 70S ACROSS MUCH OF THE SD
PLAINS...60S BEHIND THE FRONT ACROSS NORTHEASTERN WY AND INTO THE
BLACK HILLS. WITH LOW LEVEL JET IN PLACE...WINDS ARE SOUTH TO
SOUTHEAST AND GUSTY ACROSS PORTIONS OF THE SD PLAINS.
COLD FRONT WILL CONTINUE TO TRACK SLOWLY EAST ACROSS THE CWA THIS
MORNING...REACHING CENTRAL SD AROUND 18Z AND THEN STALLING OUT THERE
IN THE AFTERNOON. HIGHS WILL BE IN THE MID 70S TO MID 80S...WARMEST
OVER SOUTHERN AND EASTERN PORTIONS OF THE CWA. GUSTY NORTHWESTERLY
WINDS WILL DEVELOP FOR A FEW HOURS BEHIND THE FRONT THIS MORNING IN
SOME AREAS...ESPECIALLY FROM 2WX TO THE RAP AREA. SHOWERS AND STORMS
AHEAD OF THE FRONT WILL MOVE EAST AND OUT OF THE AREA DURING THE
EARLY MORNING. MUCH DRIER AIR WILL BUILD IN FROM THE WEST BEHIND THE
FRONT. BY THE AFTERNOON...ANY CHANCES FOR SHOWERS ADN STORMS SHOULD
BE LIMITED TO FAR EASTERN PORTIONS OF THE CWA FROM PERKINS COUNTY TO
SOUTH CENTRAL SD. WITH THE FRONT STALLING OVER SOUTH CENTRAL
SD...THERE IS A THREAT FOR A STRONG TO SEVERE STORM OR TWO DURING
THE EARLY TO MID AFTERNOON IN THE WINNER AREA...WITH BETTER CHANCES
FURTHER TO THE EAST.
WINDS WILL TURN EAST TO NORTHEAST TONIGHT...BRINGING INCREASING
LOW LEVEL MOISTURE BACK INTO THE AREA. AS UPPER LOW ROTATES ACROSS
THE NORTHERN ROCKIES...SHORTWAVE ENERGY WILL MOVE ACROSS THE
REGION...ESPECIALLY DURING THE OVERNIGHT. WILL KEEP CHANCES FOR
SHOWERS AND STORMS OVER MOST OF THE AREA...WITH THE BEST CHANCES
OVER NORTHWESTERN PORTIONS OF THE CWA. SOME OF THIS ACTIVITY COULD
LINGER INTO FRIDAY MORNING...ESPECIALLY OVER NORTHERN PORTIONS OF
THE CWA.
ON FRIDAY...LOW LEVEL MOISTURE WILL CONTINUE TO INCREASE AS WINDS
BECOME EAST TO SOUTHEAST IN MOST AREAS. ATMOSPHERE WILL BECOME
VERY UNSTABLE IN THE AFTERNOON...WITH CAPE VALUES OF 1500 TO
3000 J/KG EXPECTED ACROSS MOST OF THE CWA. SHEAR WILL BECOME MORE
FAVORABLE FOR SUPERCELLS AS WELL BY LATE AFTERNOON. THERE IS
UNCERTAINTY WITH REGARD TO TIMING OF STORM DEVELOPMENT...DEPENDING
MOSTLY ON WHEN THE PREVIOUS NIGHT/MORNING CONVECTION EXITS AND HOW
QUICKLY THE NEXT DISTURBANCE ARRIVES. ASSUMING TEMPS WARM AS
EXPECTED...UPPER 70S TO UPPER 80S...CAP WILL ERODE IN THE AFTERNOON
AND EARLY EVENING FROM WEST TO EAST. WITH ALL THESE ELEMENTS IN
PLACE...IT COULD BE A RATHER ACTIVE DAY FOR SEVERE WEATHER. THERE IS
A SLIGHT RISK FOR SEVERE STORMS ACROSS THE ENTIRE CWA FOR MUCH OF
THE AFTERNOON AND EVENING. LARGE HAIL AND STRONG WIND GUSTS WILL BE
THE MAIN THREATS. AN ISOLATED TORNADO THREAT LOOKS MOST FAVORABLE
ACROSS FAR SOUTHWESTERN SD LATE IN THE DAY.
&&
.LONG TERM...SATURDAY THROUGH WEDNESDAY
ISSUED AT 335 AM MDT THU JUN 20 2013
SHORTWAVE AT BOTTOM OF UPPER LOW WILL EJECT INTO THE DAKOTAS
SATURDAY. LOW PRESSURE WILL DEVELOP AHEAD OF THE SHORTWAVE OVER
EASTERN WY/WESTERN NE/SD. PERSISTENT EASTERLY BOUNDARY LAYER FLOW
AHEAD OF LOW WILL BRING MODERATE/STRONG INSTABILITY AND 0-6KM
SHEAR TO THE CWA...ESPECIALLY IN SD. POTENTIAL ACTIVE SEVERE
WEATHER DAY WITH VERY LARGE HAIL POSSIBLE...AS WELL AS ISOLATED
TORNADOES.
UPPER LEVEL RIDGE REDEVELOPS BEHIND SYSTEM FOR SUNDAY INTO NEXT
WEEK. ALTHOUGH ISOLATED TSRA MAY OCCUR WITH ANY RIDGE RIDERS...MUCH
DRIER AIR AS WELL AS STRONG WARMING ALOFT SHOULD PROHIBIT ANY
ORGANIZED CONVECTION. TEMPERATURES WILL BE QUITE WARM.
&&
.AVIATION...FOR THE 18Z TAFS THROUGH 18Z FRIDAY AFTERNOON
ISSUED AT 1122 AM MDT THU JUN 20 2013
A COLD FRONT WILL STALL OVER SOUTH CENTRAL SOUTH DAKOTA THIS
AFTERNOON. AHEAD OF THE FRONT...GUSTY SOUTHERLY WINDS ARE EXPECTED
WITH NORTHWEST WINDS BEHIND THE FRONT. TSRA ARE POSSIBLE ALONG AND
NEAR FRONT...MAINLY ACROSS CENTRAL SD THIS AFTERNOON AND EVENING.
ISOLATED THUNDERSTORMS ARE ALSO POSSIBLE OVER NORTHEASTERN WYOMING
DURING THE EVENING. GREATER COVERAGE OF THUNDERSTORMS IS EXPECTED
OVER NORTHEASTERN WYOMING AND PARTS OF WESTERN SOUTH DAKOTA ON
FRIDAY. MVFR CIGS MAY DEVELOP OVER SOUTHWESTERN SOUTH DAKOTA LATE
TONIGHT...IMPROVING TO VFR AGAIN BY MID DAY.
&&
.UNR WATCHES/WARNINGS/ADVISORIES...
SD...NONE.
WY...NONE.
&&
$$
SHORT TERM...26
LONG TERM...HELGESON
AVIATION...10
AREA FORECAST DISCUSSION FOR WESTERN SD AND NORTHEASTERN WY
NWS RAPID CITY SD
337 AM MDT THU JUN 20 2013
.SHORT TERM...TODAY THROUGH FRIDAY NIGHT
ISSUED AT 335 AM MDT THU JUN 20 2013
CURRENT SURFACE ANALYSIS SHOWS LOW PRESSURE OVER NORTHWESTERN
SD...WITH COLD FRONT STRETCHING SOUTH-SOUTHWESTWARD ACROSS THE
BLACK HILLS INTO EASTERN WY. UPPER LEVEL ANALYSIS HAS LOW OVER THE
PACIFIC NW...WITH SOUTHWESTERLY FLOW AHEAD OF IT ACROSS THE
ROCKIES AND NORTHERN PLAINS. REGIONAL RADARS SHOW A LINE OF STRONG
TO SEVERE STORMS OVER FAR NORTHEASTERN MT INTO WESTERN ND...WITH
OTHER SHOWER AND THUNDERSTORM ACTIVITY FURTHER SOUTH ACROSS
WESTERN SD INTO WESTERN NEB. A COUPLE OF STORMS ACROSS OUR AREA
HAS BEEN ON THE STRONG SIDE WITH GUSTY WINDS AND SMALL HAIL. TEMPS
ARE VERY WARM AHEAD OF THE FRONT...WITH 70S ACROSS MUCH OF THE SD
PLAINS...60S BEHIND THE FRONT ACROSS NORTHEASTERN WY AND INTO THE
BLACK HILLS. WITH LOW LEVEL JET IN PLACE...WINDS ARE SOUTH TO
SOUTHEAST AND GUSTY ACROSS PORTIONS OF THE SD PLAINS.
COLD FRONT WILL CONTINUE TO TRACK SLOWLY EAST ACROSS THE CWA THIS
MORNING...REACHING CENTRAL SD AROUND 18Z AND THEN STALLING OUT THERE
IN THE AFTERNOON. HIGHS WILL BE IN THE MID 70S TO MID 80S...WARMEST
OVER SOUTHERN AND EASTERN PORTIONS OF THE CWA. GUSTY NORTHWESTERLY
WINDS WILL DEVELOP FOR A FEW HOURS BEHIND THE FRONT THIS MORNING IN
SOME AREAS...ESPECIALLY FROM 2WX TO THE RAP AREA. SHOWERS AND STORMS
AHEAD OF THE FRONT WILL MOVE EAST AND OUT OF THE AREA DURING THE
EARLY MORNING. MUCH DRIER AIR WILL BUILD IN FROM THE WEST BEHIND THE
FRONT. BY THE AFTERNOON...ANY CHANCES FOR SHOWERS ADN STORMS SHOULD
BE LIMITED TO FAR EASTERN PORTIONS OF THE CWA FROM PERKINS COUNTY TO
SOUTH CENTRAL SD. WITH THE FRONT STALLING OVER SOUTH CENTRAL
SD...THERE IS A THREAT FOR A STRONG TO SEVERE STORM OR TWO DURING
THE EARLY TO MID AFTERNOON IN THE WINNER AREA...WITH BETTER CHANCES
FURTHER TO THE EAST.
WINDS WILL TURN EAST TO NORTHEAST TONIGHT...BRINGING INCREASING
LOW LEVEL MOISTURE BACK INTO THE AREA. AS UPPER LOW ROTATES ACROSS
THE NORTHERN ROCKIES...SHORTWAVE ENERGY WILL MOVE ACROSS THE
REGION...ESPECIALLY DURING THE OVERNIGHT. WILL KEEP CHANCES FOR
SHOWERS AND STORMS OVER MOST OF THE AREA...WITH THE BEST CHANCES
OVER NORTHWESTERN PORTIONS OF THE CWA. SOME OF THIS ACTIVITY COULD
LINGER INTO FRIDAY MORNING...ESPECIALLY OVER NORTHERN PORTIONS OF
THE CWA.
ON FRIDAY...LOW LEVEL MOISTURE WILL CONTINUE TO INCREASE AS WINDS
BECOME EAST TO SOUTHEAST IN MOST AREAS. ATMOSPHERE WILL BECOME
VERY UNSTABLE IN THE AFTERNOON...WITH CAPE VALUES OF 1500 TO
3000 J/KG EXPECTED ACROSS MOST OF THE CWA. SHEAR WILL BECOME MORE
FAVORABLE FOR SUPERCELLS AS WELL BY LATE AFTERNOON. THERE IS
UNCERTAINTY WITH REGARD TO TIMING OF STORM DEVELOPMENT...DEPENDING
MOSTLY ON WHEN THE PREVIOUS NIGHT/MORNING CONVECTION EXITS AND HOW
QUICKLY THE NEXT DISTURBANCE ARRIVES. ASSUMING TEMPS WARM AS
EXPECTED...UPPER 70S TO UPPER 80S...CAP WILL ERODE IN THE AFTERNOON
AND EARLY EVENING FROM WEST TO EAST. WITH ALL THESE ELEMENTS IN
PLACE...IT COULD BE A RATHER ACTIVE DAY FOR SEVERE WEATHER. THERE IS
A SLIGHT RISK FOR SEVERE STORMS ACROSS THE ENTIRE CWA FOR MUCH OF
THE AFTERNOON AND EVENING. LARGE HAIL AND STRONG WIND GUSTS WILL BE
THE MAIN THREATS. AN ISOLATED TORNADO THREAT LOOKS MOST FAVORABLE
ACROSS FAR SOUTHWESTERN SD LATE IN THE DAY.
&&
.LONG TERM...SATURDAY THROUGH WEDNESDAY
ISSUED AT 335 AM MDT THU JUN 20 2013
SHORTWAVE AT BOTTOM OF UPPER LOW WILL EJECT INTO THE DAKOTAS
SATURDAY. LOW PRESSURE WILL DEVELOP AHEAD OF THE SHORTWAVE OVER
EASTERN WY/WESTERN NE/SD. PERSISTENT EASTERLY BOUNDARY LAYER FLOW
AHEAD OF LOW WILL BRING MODERATE/STRONG INSTABILITY AND 0-6KM
SHEAR TO THE CWA...ESPECIALLY IN SD. POTENTIAL ACTIVE SEVERE
WEATHER DAY WITH VERY LARGE HAIL POSSIBLE...AS WELL AS ISOLATED
TORNADOES.
UPPER LEVEL RIDGE REDEVELOPS BEHIND SYSTEM FOR SUNDAY INTO NEXT
WEEK. ALTHOUGH ISOLATED TSRA MAY OCCUR WITH ANY RIDGE RIDERS...MUCH
DRIER AIR AS WELL AS STRONG WARMING ALOFT SHOULD PROHIBIT ANY
ORGANIZED CONVECTION. TEMPERATURES WILL BE QUITE WARM.
&&
.AVIATION...FOR THE 12Z TAFS THROUGH 12Z FRIDAY MORNING
ISSUED AT 335 AM MDT THU JUN 20 2013
A COLD FRONT WILL SLIP THROUGH THE AREA EARLY THIS MORNING INTO
THE AFTERNOON HOURS. AHEAD OF THE FRONT...GUSTY SOUTHEAST WINDS
ARE EXPECTED. BEHIND THE FRONT...EXPECT A WIND SHIFT TO THE
NORTHWEST ALONG WITH A SHORT PERIOD OF GUSTY NORTHWEST WINDS. TSRA
ARE POSSIBLE AHEAD OF THE FRONT...MAINLY ACROSS SOUTHWEST TO
CENTRAL SD THIS MORNING AND THEN OVER CENTRAL SD THIS AFTERNOON.
ISOLATED TSRA MAY DEVELOP LATER TONIGHT ACROSS THE ENTIRE REGION.
VFR CONDITIONS WILL PREVAIL EXCEPT FOR IFR/LIFR CONDITIONS IN ANY
STORMS.
&&
.UNR WATCHES/WARNINGS/ADVISORIES...
SD...NONE.
WY...NONE.
&&
$$
SHORT TERM...26
LONG TERM...HELGESON
AVIATION...HELGESON
AREA FORECAST DISCUSSION...UPDATED
NWS NASHVILLE TN
1135 PM CDT WED JUN 19 2013
.UPDATE...FOR 06Z AVIATION DISCUSSION.
&&
.AVIATION...06Z AVIATION DISCUSSION.
UNCERTAINTIES...MVFR/IFR FOG POTENTIAL CSV 20/09Z-20/13Z AND IMPACTS OF ISO
SHWRS/TSTMS TAF SITES 20/15Z-21/02Z. OVERALL SFC RIDGING INFLUENCES AND
GENERALLY DRY NWLY FLOW ALOFT RESULT IN MAINLY VFR CONDITIONS THRU 21/06Z.
BEST OVERALL LOW LEVEL MOISTURE POOLING POTENTIAL...ALONG WITH CALMS WINDS
AND RADIATIONAL AFFECTS...AT CSV...MVFR FOG REDUCED VSBYS 20/05Z AND IFR
REDUCED FOG VSBYS 20/09Z. ISO SHWRS/TSTMS POSSIBLE 20/15Z-21/02Z...BUT
PINPOINTING ACTUAL DEVELOPMENTAL LOCATIONS STILL QUITE UNCERTAIN PER
CONVECTION DRIVEN BY MAINLY LOCAL DIURNAL/LIFTING MECHANISM AFFECTS.
&&
.PREV DISCUSSION... /ISSUED 649 PM CDT WED JUN 19 2013/
UPDATE...FOR 00Z AVIATION DISCUSSION.
AVIATION...00Z AVIATION DISCUSSION.
UNCERTAINTIES...MVFR/IFR FOG POTENTIAL CSV 20/09Z-20/13Z AND IMPACTS OF ISO
SHWRS/TSTMS TAF SITES. OVERALL SFC RIDGING RIDGING INFLUENCES ALONG WITH
GENERALLY DRY NWLY FLOW ALOFT WILL RESULT IN VFR CONDITIONS THRU 20/24Z.
LOOKS LIKE BEST LOW LEVEL MOISTURE POOLING POTENTIAL...ALONG WITH CALMS WINDS
AND RADIATIONAL AFFECTS WILL BE AT CSV...AND HAVE THUS MENTIONED MVFR FOG
REDUCED VSBYS BY 20/05Z AND IFR REDUCED FOG REDUCED VSBYS BY 20/09Z. ISO
SHWRS/TSTMS POSSIBLE FROM 20/15Z-20/24Z...BUT PINPOINTING ACTUAL DEVELOPMENTAL
LOCATION QUITE UNCERTAIN AT THIS TIME PER CONVECTION BEING DRIVEN BY MAINLY
LOCAL DIURNAL AND LIFTING MECHANISM AFFECTS.
PREV DISCUSSION... /ISSUED 643 PM CDT WED JUN 19 2013/
UPDATE...
A FEW ISOL SHOWERS HAVE DEVELOPED OVER THE PAST FEW HOURS.
HOWEVER...THE CONVECTION IS SHORT LIVED AND APPEARS TO BE DYING OUT.
MEAN STORM MOTION IS A SLOW DRIFT TOWARD THE SOUTHEAST. LAPS DOES
REVEAL STRONGER CAPES OVER WESTERN TN WHERE THE STRONGEST...BUT
STILL ISOL...CONVECTION IS OCCURRING. LATEST LAPS TRENDS DO SHOW
DECREASING CAPES AND THE LATEST HRRR LOOP SHOWS NO REDEVELOPMENT
OVERNIGHT.
FOR THE FORECAST...WILL WAIT UNTIL ABOUT 8PM OR SO...AND THEN
UPDATE AND REMOVE THE EVENING CONVECTION. REMAINDER OF FCST
APPEARS TO BE IN GOOD SHAPE. LOW DEW POINT DEPRESSIONS SHOULD NOT
BE AN ISSUE OVERNIGHT. ALSO...TOVER VALUES LOOK NO LOWER THAN A -3
AT CKV. VSBYS SHOULD REMAIN AOA 1SM SO NO NEED TO INCLUDE FOG IN
FCST.
PREV DISCUSSION... /ISSUED 239 PM CDT WED JUN 19 2013/
DISCUSSION...
STARTING TO SEE A FEW CELLS DEVELOPING IN FAR NORTHEAST ARKANSAS AND
BOOTHEEL AREA OF MISSOURI...THIS IN AN AREA OF -7 LI`S AND SBCAPE
OF 2500 J/KG. ALSO LIGHT SURFACE WIND CONVERGENCE INTO THAT AREA
AT 19Z. WE DO HAVE ONE OR TWO CELLS HERE IN THE MID STATE IN
MARSHALL COUNTY AND IN VAN BUREN AND WHITE COUNTIES. NOT MUCH IN
THE WAY OF MOVEMENT ON ANY OF THIS STUFF BUT THEY DO APPEAR TO BE
SINKING SLOWLY SOUTH. GOOD CU FIELD ACROSS KENTUCKY AND TENNESSEE
THIS AFTERNOON BUT AT THIS TIME VERTICAL DEVELOPMENT IS LACKING
ACROSS MUCH OF THE AREA. EXPECT ISOLATED ACTIVITY TO CONTINUE
DEVELOPING THROUGH THE AFTERNOON AND INTO THE EARLY PART OF THE
EVENING THEN DISSIPATE AROUND SUNSET. WILL KEEP A DRY FORECAST FOR
TONIGHT. NOT ANTICIPATING ANY FOG ISSUES SINCE SLIGHTLY DRIER AIR
WILL BE FILTERING INTO THE MID STATE FROM THE NORTH. SURFACE HIGH
SHIFTS EAST AND OFF THE ATLANTIC SEABOARD ON THURSDAY BUT THERE
WILL BE ENOUGH MOISTURE IN THE TROPOSPHERE FOR ISOLATED STORMS IN
THE AFTERNOON AND EVENING AS TEMPS WARM UP TO AROUND 90 WITH
LOWER 90S ALONG THE ALABAMA BORDER AND MIDDLE 80S ON THE PLATEAU.
FRIDAY WILL USHER IN THE FIRST DAY OF SUMMER WHICH BEGINS AT 12:04
AM C.D.T. (JUST AFTER MIDNIGHT THURSDAY NIGHT INTO FRIDAY MORNING).
THE WEATHER WILL ALSO FEEL SUMMERY FRIDAY THROUGH THE WEEKEND AS
SURFACE RIDGE FROM THE ATLANTIC TAKES ON THE LOOK OF A BERMUDA
HIGH WHILE A SOMEWHAT DIRTY UPPER RIDGE BUILDS THIS WAY FROM
SOUTHERN AND CENTRAL PLAINS. THE 5-WAVE GFS 500 MBAR PATTERN
FRIDAY INTO NEXT WEEK STRENGTHENS THE ATLANTIC RIDGE ACROSS
FLORIDA AND GULF REGION WHICH MEANS TEMPS AVERAGING ABOVE NORMAL
FOR THE MID STATE. GFS ALSO HAS 20 TO 30 PERCENT RAIN CHANCES FOR THE
MID STATE JUST ABOUT EACH DAY THROUGH THE WEEKEND INTO THE FIRST
OF NEXT WEEK.
BOYD
&&
.OHX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
31
AREA FORECAST DISCUSSION
NWS LUBBOCK TX
652 PM CDT FRI JUN 21 2013
.UPDATE...
DISTURBANCE EDGING INTO WESTERN NEW MEXICO EXPECTED TO LEAD TO
INCREASING THUNDERSTORMS THROUGH THE EVENING...SHOULD PERSIST
LATER THAN LAST NIGHT. INITIAL ACTIVITY NEAR THE NEW MEXICO BORDER
FAIRLY ISOLATED AND STILL UNCERTAIN HOW MUCH ADDITIONAL DEVELOPMENT
WILL OCCUR...MIXED SIGNALS FROM SHORT-TERM SOLUTIONS. HAIL AND
HIGH WIND THREAT SHOULD TRANSITION TO OUTFLOW DRIVEN STORMS WITH
WIND AND DUST AS PROBABLE ISSUES. SEVERE THUNDERSTORM WATCH VALID
UNTIL 2 AM CDT TONIGHT. RMCQUEEN
&&
.AVIATION...
A FEW ISOLATED THUNDERSTORMS HAVE DEVELOPED NEAR THE TEXAS/NEW
MEXICO STATE LINE AND WILL CONTINUE TO MOVE EAST THIS EVENING.
HOWEVER...CONFIDENCE IS LOW ON WHETHER ANY STORMS WILL AFFECT EITHER
TAF SITE. WINDS WILL PICK UP TOMORROW AFTERNOON AGAIN AND LEAD TO
LIGHT VISIBILITY RESTRICTIONS DUE TO BLOWING DUST.
&&
.PREV DISCUSSION... /ISSUED 316 PM CDT FRI JUN 21 2013/
SHORT TERM...
FORECAST REVOLVES AROUND THUNDER CHANCES LATE THIS AFTERNOON INTO
TONIGHT. THE REGION REMAINS UNDER SOUTHWEST FLOW ALOFT...WITH ONE
NOTABLE SHORTWAVE TROUGH ACROSS THE PANHANDLES EXITING TO THE
NORTHEAST AND ANOTHER AREA OF LIFT SEEN ON WATER VAPOR IMAGERY
APPROACHING THROUGH AZ. WAS CONCERNED THE FIRST WAVE COULD SPARK A
FEW STORMS ACROSS THE EASTERN ZONES THIS AFTERNOON...AS EARLIER RAP
AND HRRR SOLUTIONS SUGGESTED...BUT THEY HAVE NOW BACKED OFF ON THIS
AND WITH WAVE EXITING PROSPECTS FOR THIS ARE LOW. ALTHOUGH WE WILL
BE POSITIONED BETWEEN THE TWO SYNOPTIC AREAS OF FORCING FOR ASCENT
THIS EVENING...STRONG HEATING AND GOOD MOISTURE LEVELS WERE
RESULTING IN STRONG INSTABILITY AND MINIMAL INHIBITION OVER MUCH OF
THE REGION...WITH 19Z MLCAPE VALUES ANALYZED AOA 2500 J/KG FOR MOST
OF THE FA. IN ADDITION...AN AREA OF LOW-LEVEL MOISTURE CONVERGENCE
WAS NOTED FROM THE CENTRAL TEXAS PANHANDLE SOUTHWESTWARD INTO THE
LEE TROUGH ACROSS SOUTHEASTERN NEW MEXICO. UP TO THIS POINT...STORMS
HAVE BEEN CONFINED TO LOCATIONS IMMEDIATELY ALONG AND EAST OF THE
SACRAMENTO MOUNTAINS...BUT EXPECT ADDITIONAL DEVELOPMENT
NORTHEASTWARD FROM THERE UP INTO THE WESTERN/CENTRAL PANHANDLE
THROUGH LATE THIS AFTERNOON. THE ACTIVITY MAY TRY AND CONGEAL
SOMEWHAT AS IT MOVES EASTWARD ACROSS THE CAPROCK THIS
EVENING...PERHAPS MAKING IT INTO THE ROLLING PLAINS LATER
TONIGHT...THOUGH IT SHOULD BE WANING IN INTENSITY BY LATE EVENING.
EARLY ON...STRONG INSTABILITY AND WEAK TO MODEST WIND SHEAR WILL
SUPPORT A SEVERE THREAT WITH LARGE HAIL...DAMAGING WINDS...LOCALLY
HEAVY RAIN AND THE PROSPECTS FOR BLOWING DUST. HAVE EXPANDED CHANCE
POPS TO ENCOMPASS NEARLY THE ENTIRE SOUTHERN PANHANDLE AND SOUTH
PLAINS THROUGH 06Z BEFORE DROPPING POPS BELOW 15 PERCENT AFTER 06Z.
TEMPERATURES TONIGHT WILL BE MILD AS MOIST SOUTHERLY LOW-LEVEL FLOW
CONTINUES AND HAVE GONE WITH TEMPERATURES SIMILAR TO WHAT WE SAW
THIS MORNING.
TOMORROW WILL BRING ANOTHER HOT DAY WITH LITTLE CHANGE IN THE
OVERALL PATTERN. STRONG DAYTIME HEATING...WITH HIGHS IN THE MIDDLE
90S AND SUFFICIENT MOISTURE...COMBINED WITH CONVERGENCE ALONG A SFC
TROUGH/DRYLINE WILL BRING ANOTHER THREAT OF STRONG/SEVERE
STORMS...FAVORING THE WESTERN ZONES INITIALLY IN THE LATE AFTERNOON
HOURS...THEN EXPANDING EAST.
LONG TERM...
MAIN ISSUE TODAY IS TIMING TRANSITION FROM AFTN THUNDERSTORM
REGIME ACROSS THE WRN ZONES TO HOT AND DRY AREAWIDE. 12Z MODEL
RUNS NOW A BIT SLOWER IN REPLACING THE WRN CONUS UPPER TROUGH WITH
AN AMPLIFYING RIDGE. IT NOW LOOKS LIKE THE LEE SFC TROUGH COULD
REMAIN ACTIVE INTO MONDAY WITH SWLY FLOW ALOFT BEFORE THAT RIDGE
AMPLIFICATION BEGINS OVER THE SRN ROCKIES. THAT SHOULD FINALLY
SHUT PRECIPITATION DOWN OVER THE AREA. AS A RESULT HAVE EXTENDED
SLIGHT CHANCE MENTION INTO MONDAY AFTN AND EVENING. TEMPS WILL
THEN WARM AS THE RIDGE BUILDS OVER THE ROCKIES AND LOW LEVELS DRY
OUT A BIT...WITH HIGH TEMPS LIKELY APPROACHING 10F WARMER THAN
NORMAL BY WEDNESDAY AND THURSDAY. WILL END WITH MENTION OF AN
OUTSIDE SHOT OF PRECIP REENTERING THE PICTURE TOWARD FRIDAY AS
NORTHERLY MID TO UPPER FLOW OVER THE PLAINS COULD SEND A COLD
FRONT AND/OR UPPER DISTURBANCE TOWARD THE FCST AREA. FOR NOW THAT
POSSIBILITY TOO REMOTE TO ADD TO FCST.
&&
.PRELIMINARY POINT TEMPS/POPS...
FRIONA 64 93 63 94 63 / 30 20 20 20 20
TULIA 66 94 66 96 67 / 30 20 20 20 20
PLAINVIEW 68 93 68 95 68 / 30 20 20 20 20
LEVELLAND 69 93 68 93 69 / 30 20 20 20 20
LUBBOCK 73 93 70 96 69 / 30 10 20 20 20
DENVER CITY 67 95 68 96 69 / 30 20 20 20 20
BROWNFIELD 70 94 68 95 70 / 30 20 20 20 20
CHILDRESS 72 97 70 97 70 / 20 10 10 10 10
SPUR 72 95 71 95 70 / 20 10 10 10 10
ASPERMONT 73 97 72 97 71 / 20 10 10 10 10
&&
.LUB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
05/99/01
AREA FORECAST DISCUSSION
NWS SAN ANGELO TX
1203 AM CDT THU JUN 20 2013
.DISCUSSION...
LOOK FOR VFR CONDITIONS TO DOMINATE WEST CENTRAL TEXAS FOR THE
NEXT 24 HOURS. SEE AVIATION BELOW FOR DETAILS.
&&
.AVIATION...
MODELS THIS CYCLE STILL DO NOT INCREASE MY CONFIDENCE FOR
ORGANIZED STRATUS RETURN LATER TONIGHT. THE NAM 925 MB RELATIVE
HUMIDITY FIELD DATA INDICATE STRATUS MAY RETURN TO OUR SOUTHERN
COUNTIES BY 12Z. HOWEVER...THE GFS DATA DO NOT SHOW ANYTHING AS
ORGANIZED. PLUS...HIGHER CLOUDS A CURRENTLY MOVING OVER WEST
CENTRAL TEXAS. THUS...MY CONFIDENCE STILL IS NOT VERY HIGH
REGRADING STRATUS RETURN. SO...ALL TERMINALS ARE VFR AGAIN THIS
CYCLE. SURFACE WINDS STILL LOOK GUSTY TOMORROW...WITH A DECREASE
TOMORROW EVENING.
HUBER
&&
.PREV DISCUSSION... /ISSUED 738 PM CDT WED JUN 19 2013/
DISCUSSION...
LOOK FOR VFR CONDITIONS TO DOMINATE WEST CENTRAL TEXAS FOR THE
NEXT 24 HOURS. AVIATION BELOW HAS DETAILS.
AVIATION...
MODELS CONTINUE AN UPPER RIDGE OVER TEXAS FOR THE NEXT 24 HOURS.
THE NAM 925 MB RELATIVE HUMIDITY FIELD DOES INDICATE STRATUS MAY
RETURN TO OUR SOUTHERN COUNTIES OVERNIGHT. HOWEVER...THE GFS IS
LESS AGGRESSIVE WITH POSSIBLE STRATUS RETURN. THUS...FOR THIS CYCLE
I DECIDED NOT TO INCLUDE ANY MVFR CEILINGS IN ANY OF OUR
TERMINALS. ASIDE FROM GUSTY NORTHERLY SURFACE WINDS EARLY THIS
EVENING FROM THUNDERSTORM OUTFLOW...PLAN FOR LIGHT SOUTHERLY
SURFACE WINDS TONIGHT AROUND 10 KNOTS OR LESS. FOR
TOMORROW...EXPECT GUSTY SOUTH TO SOUTHEASTERLY SURFACE WINDS...AS
A LEE SURFACE TROUGH ACROSS EASTERN NEW MEXICO AND FAR WEST TEXAS
BECOMES MORE DOMINATE.
HUBER
PREV DISCUSSION... /ISSUED 340 PM CDT WED JUN 19 2013/
SHORT TERM...
STRONG TO SEVERE CONVECTION IS ONGOING ACROSS THE BIG COUNTRY THIS
AFTERNOON. THIS ACTIVITY IS OCCURRING IN THE VICINITY OF A SLOWLY
SOUTHWARD MOVING SURFACE BOUNDARY DRAPED FROM NORTHWEST TO SOUTHEAST
FROM NEAR LAMESA...TO SWEETWATER...TO BRECKENRIDGE. THE ENVIRONMENT
IS QUITE UNSTABLE...AS EVIDENT FROM THE MLCAPE VALUES AT OR ABOVE
3000 J/KG. EFFECTIVE SHEAR VALUES OF NEAR 40 KTS HAVE MAINTAINED
ORGANIZATION IN THIS CONVECTION WITH AT LEAST TWO SUPERCELLS
EMBEDDED WITHIN THE CLUSTER. THIS ACTIVITY WILL CONTINUE TO MOVE TO
THE SOUTHEAST THIS AFTERNOON...LINGERING INTO THE EVENING HOURS AND
MAINLY AFFECTING THE BIG COUNTRY AND NORTHERN HEARTLAND. I HAVE
NOTED THE HRRR INDICATING A LATE NIGHT PRECIP POTENTIAL FOR THE
CONCHO VALLEY BUT I AM PLAYING THIS MORE CONSERVATIVE AND KEEPING
THE FORECAST DRY FOR THE SOUTHERN COUNTIES. EXPECT OVERNIGHT LOWS
GENERALLY IN THE LOWER 70S. HOWEVER...SOME RAIN COOLED AREAS WILL
LIKELY DIP INTO THE 60S.
TOMORROW...THE RIDGE IS EXPECTED TO TAKE CONTROL WITH HOT AND DRY
CONDITIONS AREAWIDE. TEMPS WILL WARM INTO THE MID 90S ACROSS WEST
CENTRAL TX WITH SOUTH WINDS OF 15-20 MPH.
LONG TERM...
A STEADY-STATE PATTERN OF HOT AND DRY CONDITIONS ARE EXPECTED FOR
WEST CENTRAL TEXAS...FRIDAY THROUGH THE MIDDLE OF NEXT WEEK.
SUBTROPICAL RIDGE WILL BE OUR DOMINANT WEATHER INFLUENCE. THIS
FEATURE WILL BUILD/EXPAND NORTHEAST FROM TEXAS TOWARD THE LOWER
GREAT LAKES ON FRIDAY...AND WILL REMAIN ANCHORED OVER TEXAS
THROUGH THE WEEKEND AND FIRST PART OF NEXT WEEK. BY THE MIDDLE OF
NEXT WEEK...THE GFS AND ECMWF SHIFT THE CENTER OF THE UPPER HIGH
NORTHWEST INTO NEW MEXICO AND COLORADO. ASSOCIATED SUBSIDENCE
WILL HELP TO KEEP OUR RAIN CHANCES MINIMAL.
THE LOW-LEVEL THERMAL RIDGE WILL REMAIN CENTERED TO OUR WEST...
WITH SOME EASTWARD EXPANSION INDICATED NEXT WEEK. WITH THIS
PATTERN AND INCREASED SOIL MOISTURE FROM RECENT RAINFALL AND
EVAPOTRANSPIRATIVE EFFECTS...EXPECT LITTLE CHANGE IN THE DAILY
TEMPERATURES THROUGH MONDAY. COULD HAVE MAXIMUM TEMPERATURES
CREEPING UP A FEW DEGREES AS THE WEEK PROGRESSES HOWEVER.
&&
.PRELIMINARY POINT TEMPS/POPS...
ABILENE 73 95 73 95 73 / 20 0 0 0 0
SAN ANGELO 73 96 72 96 72 / 20 0 0 0 0
JUNCTION 71 94 71 93 71 / 10 0 0 0 0
&&
.SJT WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
HUBER
AREA FORECAST DISCUSSION
NWS AMARILLO TX
1130 PM CDT WED JUN 19 2013
.AVIATION...
06Z TAF CYCLE
AN UPPER RIDGE OVER THE PANHANDLES TONIGHT WILL MOVE OFF TO THE EAST
THURSDAY AND THURSDAY NIGHT. THE UPPER FLOW WILL TRANSITION TO
SOUTHWESTERLY THURSDAY ALLOWING FOR SOME HIGH LEVEL CLOUDS TO TRACK
NORTHEAST INTO THE PANHANDLES. VFR CONDITIONS WILL PREVAIL ALONG WITH
GENERALLY SOUTHERLY WINDS OF AROUND 10 TO 20 KNOTS THROUGH ABOUT 14Z
TO 15Z THURSDAY...THEN INCREASING TO AROUND 15 TO 25 KNOTS WITH
HIGHER GUSTS AFTER 14Z THURSDAY. ALTHOUGH CONVECTION COULD POSSIBLY
DEVELOP AFTER ABOUT 21Z THURSDAY TO 00Z FRIDAY AND MAY AFFECT ALL
THREE TAF SITES...CONFIDENCE TOO LOW TO MENTION IN THE TAF FORECAST
AT THIS TIME.
SCHNEIDER
&&
.PREV DISCUSSION... /ISSUED 827 PM CDT WED JUN 19 2013/
UPDATE...
HAVE CANCELLED SEVERE THUNDERSTORM WATCH THAT WAS IN EFFECT FOR THE
SOUTHWEST AND SOUTH CENTRAL TX PANHANDLE. STRONG CAP IN WAKE OF
EARLIER DAY MCS PROVED TO BE TOO MUCH FOR CONVECTION TO OVERCOME. A
FEW SHOWERS AND THUNDERSTORMS WILL REMAIN POSSIBLE ACROSS THE WESTERN
PANHANDLES AND SOUTHERN TX PANHANDLE THROUGH MIDNIGHT...BUT THEY ARE
NOT EXPECTED TO BE STRONG OR SEVERE.
KB
PREV DISCUSSION... /ISSUED 625 PM CDT WED JUN 19 2013/
UPDATE...
SEVERE THUNDERSTORM WATCH HAS BEEN ISSUED FOR THE SOUTHWEST AND SOUTH
CENTRAL TX PANHANDLE THROUGH 1 AM CDT. BIGGEST QUESTION AT THIS POINT IS
HOW WELL SEVERE STORMS WILL BE ABLE TO SUSTAIN THEMSELVES AS THEY
PROGRESS FARTHER EAST/NORTHEAST OF THE OUTFLOW BOUNDARY FROM EARLIER
DAY MCS...ENCOUNTERING A MUCH MORE STRONGLY CAPPED ATMOSPHERE
CHARACTERIZED BY INCREASING MLCIN VALUES OVER THE PAST FEW HOURS. IF
STORMS ARE ABLE TO OVERCOME THESE HIGHER MLCIN VALUES...INSTABILITY
/MLCAPE 1500-2500 J/KG/ AND DEEP LAYER SHEAR /40-50KT/ ARE VERY
FAVORABLE FOR SUPERCELLS AND AN ATTENDANT SEVERE WEATHER THREAT.
HOWEVER...THIS MORE STABLE LAYER MAY BE TOUGH TO OVERCOME...WITH
EARLY INDICATIONS SHOWING THE STORM EAST OF TUCUMCARI WEAKENING AS IT
ENCOUNTERS THIS MUCH MORE STRONGLY CAPPED ENVIRONMENT EAST OF THE
OUTFLOW. TIME WILL ULTIMATELY TELL IF THIS TREND HOLDS...BUT THE
POTENTIAL FOR LARGE HAIL AND DAMAGING WINDS IS CERTAINLY THERE IF
STORMS DO PENETRATE THE STABLE LAYER.
KB
AVIATION...
00Z TAFS...THUNDERSTORMS MAY IMPACT THE KAMA TERMINAL THIS EVENING IF
THEY HOLD TOGETHER OUT OF EASTERN NM...AND WILL COVER THIS POTENTIAL
WITH A TEMPO GROUP THROUGH 04Z. THUNDERSTORM CHANCES ARE MUCH LESS AT
KDHT AND KGUY AND WILL OMIT ANY MENTION FROM THE TAFS. OUTSIDE OF ANY
THUNDERSTORMS...VFR CONDITIONS ARE ANTICIPATED. GUSTY SOUTHEAST WINDS
WILL DISSIPATE SOME AROUND SUNSET...BUT SOME GUSTS MAY PERSIST
OVERNIGHT AT KAMA. SOUTH/SOUTHWEST WINDS WILL PICK UP AGAIN AROUND
14Z THURSDAY...WITH GUSTS NEAR 30 KTS FOR MOST OF THE DAY.
SCHNEIDER/KB
PREV DISCUSSION... /ISSUED 328 PM CDT WED JUN 19 2013/
DISCUSSION...
MORNING CONVECTION HAS HELPED TO STABILIZE THE TEXAS AND OKLAHOMA
PANHANDLES WHICH COULD KEEP PRECIPITATION CHANCES LIMITED THIS
EVENING AND TONIGHT.
CONVECTION IS ALREADY BEGINNING TO DEVELOP OVER THE NEW MEXICO
MOUNTAINS THIS AFTERNOON. THE OUTFLOW FROM OUR STORMS THIS MORNING
HAS PROGRESSED INTO THE EASTERN NEW MEXICO PLAINS BEFORE LOSING
FORWARD MOMENTUM. THE RUC HRRR HAS BEEN ADVERTISING THAT CONVECTION
WOULD DEVELOP ALONG THE WESTERN EXTENT OF THE OUTFLOW AND COMBINE
WITH STORMS OVER NEW MEXICO BEFORE MOVING ACROSS THE CENTRAL AND
SOUTHERN PANHANDLES. HOWEVER...THE RUC HRRR HAS CONSISTENTLY SHOWN
THE MCS OVER NORTHWESTERN TEXAS TAKING A MUCH FURTHER EAST TRACK
WHILE NOT PROGRESSING THE WESTERN OUTFLOW FAR ENOUGH WEST. THIS
ARGUES THAT IF CONVECTION DOES FORM ALONG THE WESTERN OUTFLOW IT
WILL HAVE TO STRUGGLE AGAINST THE OUTFLOW PROGRESS EASTWARD ENOUGH TO
REACH THE PANHANDLES. HAVE KEPT POPS LOW AND USED AREAL QUANTIFIERS
FOR THIS AFTERNOON THROUGH TONIGHT.
IF THE STORMS OVER NEW MEXICO CAN OBTAIN STRONG COLD POOLS THEN THEY
COULD OVERTAKE THE OUTFLOW AND TAP INTO ELEVATED INSTABILITY AS THEY
MOVE INTO THE WESTERN TEXAS AND OKLAHOMA PANHANDLES. STRONG TO
SEVERE STORMS MAY BE POSSIBLE IF THIS HAPPENS WITH HAIL AND DAMAGING
WINDS AS THE PRIMARY SEVERE HAZARDS. ALSO GIVEN AMPLE PWATS
ACROSS THE AREA...1.0 TO 1.2 INCHES...ANY STORM THAT MOVES INTO THE
TEXAS OR OKLAHOMA PANHANDLE WILL HAVE A HEAVY RAIN POTENTIAL THAT
COULD LEAD TO FLOODING AND FLASH FLOODING CONCERNS.
ANY CONVECTIVE ACTIVITY THAT OCCURS ACROSS THE PANHANDLES THIS
AFTERNOON/EVENING SHOULD DIMINISH AFTER MIDNIGHT. SATURDAY WILL SEE
THE RIDGE AXIS SHIFT TO THE EAST OF THE PANHANDLES AND OPEN UP THE
WESTERN PANHANDLES TO ANOTHER CHANCE FOR PRECIPITATION DURING THE
AFTERNOON AND EVENING HOURS. WITH CAPE VALUES OF 1500 TO 2500 J/KG
BUT WEAK DEEP LAYER SHEAR COULD LEAD TO A FEW STORMS BRIEFLY PULSING
TO STRONG TO SEVERE LEVELS THEN COLLAPSING. THIS WILL KEEP THE RISK
FOR DAMAGING WINDS AND HAIL AS THE PRIMARY HAZARDS. FRIDAY AFTERNOON
WILL BE SIMILAR TO THURSDAY/S WITH DECENT CAPE VALUES BUT VERY WEAK
DEEP LAYER SHEAR. STRONG TO BRIEFLY SEVERE STORMS WILL ONCE AGAIN BE
POSSIBLE FOR THE WESTERN TEXAS AND OKLAHOMA PANHANDLES.
SATURDAY THROUGH EARLY NEXT WEEK...WILL SEE THE RIDGE AXIS BUILD
BACK OVER THE PANHANDLES TO KEEP PRECIPITATION CHANCES LIMITED.
FIRE WEATHER...
NEITHER ELEVATED NOR FIRE WEATHER CONDITIONS ARE EXPECTED FOR THE
NEXT 7 DAYS GIVEN THE RECENT WETTING RAINS.
&&
.AMA WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
OK...NONE.
&&
$$
11/08
AREA FORECAST DISCUSSION
NWS GREEN BAY WI
1054 PM CDT FRI JUN 21 2013
UPDATED AVIATION PORTION FOR 06Z TAF ISSUANCE
.UPDATE...
ISSUED AT 829 PM CDT FRI JUN 21 2013
SMALL CLUSTER OF SVR TSTMS WITH DAMAGING WINDS NEAR MSP IS EXPECTED
TO MOVE ESE INTO CENTRAL WI LATER THIS EVG...FOLLOWING THE NORTHERN
PERIPHERY OF THE INSTABILITY/MOISTURE GRADIENT. THE STORMS SHOULD
ARRIVE IN CENTRAL WI BETWEEN 0330-0400Z. MARGINAL DAMAGING WINDS
AND BRIEF PERIODS OF TORRENTIAL RAINFALL WILL BE POSSIBLE IN OUR
SW COUNTIES LATE THIS EVG INTO THE EARLY MORNING HOURS OF
SATURDAY. WILL HAVE TO MONITOR HYDRO TRENDS OVER CENTRAL WI...
WHERE SOME LOCATIONS RECEIVED 1-2 INCHES OF RAIN OVER THE PAST
36 HOURS. WAA/ISENT LIFT SHOULD SUPPORT SCT SHRA/TSRA OVER AT
LEAST THE REST OF C/EC WI OVERNIGHT... AND THE REMNANTS OF THE
STRATIFORM PCPN SHIELD ASSOCIATED WITH THE MCV/MCS SHOULD MOVE
ACROSS N WI. WILL HAVE TO WATCH FOR WAKE LOW WINDS ON THE BACK
EDGE OF THE STRATIFORM PCPN SHIELD LATER TONIGHT. STRONG WAKE LOW
WINDS HAVE ALREADY BEEN REPORTED THIS EVG OVER E SD/SE ND/SW MN
THIS EVG...AND THE WAKE LOW GENERATION PARAMETER IS SHOWING
IMPRESSIVE VALUES TO AROUND 70 KTS IN WSTRN MN RIGHT NOW.
LOWERED MIN TEMPS A BIT OVER NORTHERN WI...WHERE A SHALLOW CANADIAN
AIR MASS CURRENTLY RESIDES.
&&
.SYNOPSIS...
ISSUED AT 241 PM CDT FRI JUN 21 2013
WARM AND HUMID WITH PLENTY OF RAIN.
THE WESTERLIES ACRS NOAM ARE SPLIT. WITHIN THE BRANCH OF THE FLOW
ACRS THE CONUS...UPR TROF WAS ACRS THE PAC NW...RIDGING EXTENDED
NWD ACRS THE PLAINS...AND A BROAD TROF WAS OVER ERN NOAM. THE UPR
FEATURES WL PROGRESS EWD A BIT EARLY IN THE FCST PERIOD...THEN A
MORE SIG ADJUSTMENT TO THE PATTERN WL TAKE PLACE NEXT WEEK...WHEN
THE MAIN FEATURES REFORM W OF THEIR CURRENT POSITIONS.
THE PATTERN FAVORS A WARM...HUMID...AND RAINY PATTERN FOR THE FCST
AREA. EXPECT NUMEROUS ROUNDS OF SHRA/TSRA AS SHRTWVS ROTG OUT OF
THE WRN TROF INTERACT WITH WARM HUMID AIR ACRS THE RGN. RAINFALL
TOTALS FOR THE PERIOD WL BE HIGH...AND POSSIBLY EXCESSIVE. THE
WARM HUMID AIR MASS WL RESULT IN ABV NORMAL TEMPS. READINGS ON
SOME OF THE DAYS COULD BE HELD DOWN IF THERE ARE WIDESPREAD CLDS
AND PCPN...BUT NIGHTTIME MINS WL PROBABLY HOLD WELL ABV NORMAL
LEVELS REGARDLESS.
&&
.SHORT TERM...TONIGHT AND SATURDAY
ISSUED AT 241 PM CDT FRI JUN 21 2013
THE LATEST RUC ANALYSIS AND SATELLITE/RADAR IMAGERY SHOW A
SHORTWAVE TROUGH MOVING EAST OVER THE UPPER PENINSULA. THE
CONVECTIVE COMPLEX TIED TO IT HAS SPLIT INTO TWO PIECES...ONE OVER
THE EASTERN UPPER PENINSULA AND THE OTHER OVER NORTHERN ILLINOIS.
STILL HAVE PLENTY OF CONVECTIVE DEBRIS ACROSS MUCH OF WISCONSIN
AND MINNESOTA EARLY THIS AFTERNOON...WHICH HAS HELD TEMPERATURES
BACK INTO THE 60S AND 70S. THE OUTFLOW BOUNDARY FROM THESE STORMS
HAS PUSHED ALL THE WAY INTO SOUTHERN IOWA AND CENTRAL ILLINOIS
WHERE STORMS ARE TRYING TO REFIRE. HOWEVER...OUR MAIN FORECAST
CONCERN REVOLVES AROUND THE SEVERE CONVECTION THAT HAS DEVELOPED
OVER SOUTH DAKOTA. THIS CONVECTION IS MOVING NORTHEAST AND ALREADY
APPEARS TO HAVE THE LOOK OF ANOTHER MCS. AS IT HEADS EAST...SEVERE
WEATHER CHANCES ARE THE MAIN FORECAST PRIORITY.
TONIGHT...THE SHORTWAVE TROUGH WILL LIFT NE TONIGHT AS MID-LEVEL
RIDGING STRENGTHENS OVER THE MISSISSIPPI VALLEY. AHEAD OF THIS
SHORTWAVE TROUGH AND ASSOCIATED SURFACE LOW...A LLJ WILL DEVELOP
AND PUSH AN 850MB WARM FRONT NORTH INTO SOUTHERN OR CENTRAL
MINNESOTA AND CENTRAL WISCONSIN. CONVECTION SHOULD BECOME ROOTED
TO THIS BOUNDARY...AS FORCING ALONG THE NOSE OF THE LLJ AND
INSTABILITY OF 1K-2K J/KG ALONG THIS FRONT SHOULD BE ABLE TO
SUSTAIN STORMS. THE 12Z MODELS HAVE A VARIETY OF SOLUTIONS OF HOW
FAR NORTH THIS FRONT REACHES WHICH OBVIOUSLY IMPACTS THE CHANCES
OF THE CONVECTION MOVING INTO THE REGION. THE LLJ WILL BE VEERING
AFTER MIDNIGHT WHICH SHOULD CAUSE THE MCS TO TURN TO THE
SOUTHEAST. SO IF THIS COMPLEX CONTINUES ON ITS ENE HEADING TOWARDS
CENTRAL MINNESOTA...IT WILL HAVE A GREATER CHANCE OF REACHING
CENTRAL WISCONSIN LATE TONIGHT AND NORTHEAST WISCONSIN IN THE
MORNING. THOUGH THE STORMS WILL BE WEAKENING AS THEY MOVE INTO
WISCONSIN...THE SQUALL LINE WILL HAVE POTENTIAL TO CREATE DAMAGING
WINDS AND SMALL HAIL...AS WELL AS ANOTHER INCH TO INCH AND A HALF
OF RAINFALL. HAVE REORIENTATED POPS TO SHOW HIGHER VALUES OVER
CENTRAL AND EAST-CENTRAL WISCONSIN AFTER MIDNIGHT...AND ANTICIPATE
MUCH IF NOT ALL OF THE AREA WILL BE DRY UNTIL THEN. MUGGY LOWS IN
THE 60S.
SATURDAY...ANTICIPATE CONVECTION TO BE MOVING THROUGH THE AREA AT
LEAST FOR THE FIRST HALF OF THE MORNING. THE COLD POOL FROM THE
CONVECTION SHOULD SUPPRESS THE SURFACE WARM FRONT TO THE SOUTH.
LIKE TODAY...SHOULD SEE A LULL IN THE CONVECTION ONCE THE MCS
DEPARTS (IF IT REACHES HERE). THEN SHORTWAVES MOVING TOWARDS
WESTERN LAKE SUPERIOR AND A SURFACE LOW OVER CENTRAL MINNESOTA
SHOULD HELP THE WESTERN PART OF THE WARM FRONT LIFT NORTH INTO
NORTHWEST OR CENTRAL WISCONSIN. PROGGED SOUNDINGS INDICATE AROUND
2K J/KG OF ML CAPE OVER NORTH-CENTRAL WISCONSIN THOUGH 0-6KM SHEAR
IS ONLY AROUND 25-30KTS. CANNOT RULE OUT A SEVERE THREAT RE-
DEVELOPING IN THE AFTERNOON IF THERE IS SUFFICIENT SURFACE
HEATING. DAMAGING WINDS AND LARGE HAIL WOULD BE THE MAIN THREATS.
.LONG TERM...SATURDAY NIGHT THROUGH FRIDAY
ISSUED AT 241 PM CDT FRI JUN 21 2013
THOUGH THE OVERALL EVOLUTION OF THE WEATHER PATTERN AND BASIC
WEATHER FORECAST ARE FAIRLY CLEAR CUT...IT REMAINS EXTREMELY
DIFFICULT TO ADD DETAIL BEYOND THE SHORT-TERM PORTION OF THE
FORECAST. THERE IS REALLY NO GETTING AROUND CARRYING A CHC OF
TSTMS THROUGH MOST OF THE PERIOD.
GIVEN THE LIKELIHOOD OF SEVERAL ROUNDS OF SHRA/TSRA...THE MAIN
HAZARD SEEMS TO BE HEAVY RAIN AND POSSIBLE FLOODING. BUT WL
PROBABLY HAVE A FEW ROUNDS OF SVR/NR SVR WX AS WELL. HUNCH HERE IS
THAT GREATEST SVR THREAT DURING THE PERIOD WL ACTUALLY HOLD OFF
UNTIL NEXT WK WHEN UPR RIDGE STARTS TO REFORM FARTHER W...AND UPR
FLOW ACRS THE FCST AREA STARTS STRENGTHEN FM THE WNW. WL MENTION
THE POTENTIAL FOR HEAVY RAINS AND SVR WX IN THE HWO...AND ISSUE AN
ESF TO FURTHER HILIGHT THE POTENTIAL FOR FLOODING.
&&
.AVIATION...FOR 06Z TAF ISSUANCE
ISSUED AT 1048 PM CDT FRI JUN 21 2013
INITIAL CLUSTER OF TSTMS HAS WEKENED AS IT MOVED TOWARD CENTRAL
WI LATE THIS EVENING. ALTHOUGH THE FIRST ROUND OF STORMS SHOULD MISS
THE TAF SITES...THERE SHOULD STILL BE A CHANCE OF STORMS ACROSS
MUCH OF C/EC WI OVERNIGHT. MVFR CONDITIONS MAY ACCOMPANY THE TSTMS.
LOW CLOUDS WILL BE FOUND ACROSS NORTHERN WI OVERNIGHT...AND MAY
ALSO BE OCCUR ACROSS C/EC WI LATE TONIGHT INTO EARLY SAT. IMPROVING
CONDITIONS ARE EXPECTED BY MID TO LATE SAT MORNING...WITH SCT TSTMS
REDEVELOPING DURING THE LATE AFTERNOON/EARLY EVENING. STRONG INSTABILITY
IS EXPECTED...SO STRONG/SEVERE TSTMS WITH TORRENTIAL RAINFALL ARE
POSSIBLE.
&&
.GRB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE.........KIECKBUSCH
SYNOPSIS.......SKOWRONSKI
SHORT TERM.....MPC
LONG TERM......SKOWRONSKI
AVIATION.......KIECKBUSCH
AREA FORECAST DISCUSSION...UPDATED
NWS MILWAUKEE/SULLIVAN WI
921 PM CDT FRI JUN 21 2013
.UPDATE...CURRENTLY SEEING AN AREA OF LIGHT SHOWERS ACROSS THE
FORECAST AREA. LATEST RAP 850 AND 925 MB TEMPERATURES SHOW A
GRADIENT ACROSS SOUTHERN WISCONSIN...WITH WARM ADVECTION LIKELY THE
MAIN TRIGGER OF THE SHOWERS. THE LATEST NAM SHOWS THAT THE 700 MB
WARM ADVECTION MAXIMUM LINES UP NICELY WITH WHERE THE SHOWERS ARE.
THE LATEST HRRR IS HANDLING THE CURRENT SITUATION THE BEST OF THE
SHORT TERM MODELS AND KEEPS ISOLATED TO SCATTERED SHOWERS GOING
THROUGH THE REMAINDER OF THE EVENING AND INTO EARLY TONIGHT. WITH
PLENTY OF MOISTURE AND DECENT ELEVATED INSTABILITY...COULD SEE
SEEM BRIEF HEAVY DOWNPOURS WITH SOME THUNDER POSSIBLE ALSO.
THINK THE BIGGEST CONCERN RIGHT NOW IS WHETHER CONVECTION UPSTREAM
WILL GET ORGANIZED AND MOVE ALONG THE INSTABILITY GRADIENT...WHICH
WOULD LIKELY EVENTUALLY BRING THE ACTIVITY INTO SOUTHERN
WISCONSIN. THE OVERALL CONSENSUS OF MODELS DOES SHOW AN AREA OF
STORMS KNOCKING ON THE DOOR BY DAYBREAK. MAIN THREAT WOULD LIKELY
BE STRONG WINDS AND HEAVY RAIN...SIMILAR TO THE STORMS THAT MOVED
THROUGH THIS MORNING. SPC IS MAINTAINING A SLIGHT RISK FOR SEVERE
STORMS ACROSS THE FORECAST AREA...EXCEPT FOR IN THE EAST. WILL
CONTINUE TO MONITOR THE UPSTREAM ACTIVITY...HOPEFULLY GETTING A
BETTER HANDLE ON THINGS OVER THE NEXT COUPLE HOURS AS THE
CONVECTION DRAWS CLOSER.
&&
.AVIATION/06Z TAFS/...HAVE RECENTLY SEEN SHOWERS POP ACROSS MUCH
OF THE FORECAST AREA. THINK WARM ADVECTION ALOFT WILL KEEP THE
CHANCE FOR SHOWERS GOING THROUGH THE REMAINDER OF THE EVENING AND
INTO THE NIGHT. WITH PLENTY OF MOISTURE AND DECENT ELEVATED
INSTABILITY...COULD SEE SEEM BRIEF HEAVY DOWNPOURS WITH SOME
THUNDER POSSIBLE ALSO.
BIGGER CONCERN IS WHETHER UPSTREAM STORMS WILL EVENTUALLY MOVE
INTO SOUTHERN WISCONSIN...LAST NIGHT AND THIS MORNING. STILL QUITE
A BIT OF UNCERTAINTY WITH THIS...PARTICULARLY WITH TIMING...SO MAY
KEEP IT MAINLY DRY IN TAFS...OTHER THAN THE CURRENT ACTIVITY. WILL
BE KEEPING A CLOSE EYE ON THE UPSTREAM CONVECTION AND UPDATE TAFS
AS THINGS HOPEFULLY BECOME MORE CLEAR OVER THE NEXT FEW HOURS.
OVERALL...VFR CONDITIONS ARE EXPECTED TO CONTINUE THROUGH
SATURDAY EXCEPT FOR LOWER VSBYS POSSIBLE WITHIN HEAVIER
SHOWERS/STORMS.
&&
.PREV DISCUSSION... /ISSUED 348 PM CDT FRI JUN 21 2013/
VERY SHORT TERM...TONIGHT AND SATURDAY. FORECAST CONFIDENCE IS LOW TO MEDIUM.
GUSTY SOUTH TO SOUTHEAST WINDS WITH WAKE LOW WILL CONTINUE TO WEAKEN
OVER THE NEXT HOUR OR TWO IN PORTIONS OF SOUTHEAST WISCONSIN. GUSTS
TO AROUND 20 KNOTS ARE THEN EXPECTED UNTIL SUNSET.
TRICKY FORECAST FOR THIS PERIOD ACROSS THE AREA. SHORT TERM MODELS
INDICATE THE SURFACE WARM FRONT WILL SHIFT NORTHWARD ACROSS THE AREA
TONIGHT...AND REMAIN JUST NORTH OF THE AREA ON SATURDAY. 18Z NAM IS
NOW KEEPING WARM FRONT OVER THE AREA ON SATURDAY...SOUTH OF THE
OTHER SYNOPTIC MODELS. 850MB WARM AIR ADVECTION REMAINS OVER THE
REGION TONIGHT AND SATURDAY.
THE 850MB LOW LEVEL JET NOSE REMAINS FOCUSED WEST OF THE REGION
TONIGHT...OVER SOUTHERN MINNESOTA INTO NORTHERN IOWA. THIS WOULD
SUPPORT FURTHER DEVELOPMENT OF CONVECTION OVER THE DAKOTAS INTO AN
MCS...WHICH MAY TRAVERSE ALONG THE WARM FRONT AND EDGE OF CAP TOWARD
AND INTO THE AREA LATER TONIGHT INTO EARLY SATURDAY MORNING.
MESOSCALE MODELS DO SHOW THIS TREND TO SOME EXTENT. THEY ALSO SHOW
SOME CONVECTION DEVELOPING NEAR THE WARM FRONT ACROSS THE NORTHERN
PORTIONS OF THE AREA LATER TONIGHT.
ALL IN ALL...THERE COULD BE AN MCS THAT AFFECTS THE AREA LATER
TONIGHT...WITH OTHER SCATTERED CONVECTION NEAR THE WARM FRONT...OR
THERE COULD BE A DRY PERIOD. FOR NOW...WILL GO WITH CHANCE POPS AT
BEST FOR TONIGHT INTO SATURDAY...GIVEN THE LOWER END CONFIDENCE. SPC
HAS SLIGHT RISK FOR TONIGHT AND AGAIN SATURDAY...AS LARGE ELEVATED
CAPE EXISTS ABOVE CAP...THOUGH DEEP LAYER SHEAR IS MODEST.
PRECIPITABLE WATER VALUES ARE HIGH...SO HEAVY RAINFALL WOULD BE
POSSIBLE IF CONVECTION DOES DEVELOP.
TEMPERATURES ARE GOING TO BE TOUGH AS WELL...DEPENDING ON CONVECTION
TRENDS AND CLOUDS. FOR NOW...WILL GO NEAR MOS GUIDANCE AND KEEP
THINGS WARM AND HUMID TONIGHT AND SATURDAY. MAY CRACK 90 IN THE FAR
SOUTH IF ENOUGH SUNSHINE OCCURS SATURDAY AFTERNOON...GIVEN 925MB
TEMPERATURES AND 2 METER TEMPERATURE TRENDS.
SHORT TERM...SATURDAY NIGHT THROUGH MONDAY.
SATURDAY NIGHT...FORECAST CONFIDENCE MEDIUM.
MID-UPPER RIDGING KEEPS BEST FORCING FOR ASCENT WITH UPPER JET
STREAK AND LOW-LEVEL JET TO THE WEST SATURDAY NIGHT INTO SUNDAY.
THE 12Z NAM IS HINTING AT A RESIDUAL BOUNDARY FROM EARLIER SATURDAY
CONVECTION WILL BE THE FOCUS FOR RE-DEVELOPMENT SATURDAY EVENING.
WHILE THIS IS PLAUSIBLE...THE NAM LAYER Q-VECTOR CONVERGENCE AND
FRONTOGENESIS IS BEST FARTHER NORTHWEST CLOSER TO WHERE OTHER MODELS
ARE FOCUSING INITIATION OF STRONGEST CONVECTION. ALSO NAM SOUNDINGS
IN LINE WITH OTHERS SHOWING A DECENT CAP WHERE 1000 J/KG OF ELEVATED
CAPE IS LIMITED BY 100 J/KG OF CIN. FORECAST CORFIDI VECTORS
INDICATE AN MCS THAT CRESTS THE THERMAL RIDGE/THICKNESS RIDGE AXIS
COULD CLIP NORTHWESTERN/WESTERN PORTIONS OF CWA SO WILL HAVE HIGHER
POPS THERE.
SUNDAY THROUGH MONDAY...FORECAST CONFIDENCE MEDIUM.
IF MODELS ARE CORRECT KEEPING THE BULK OF CONVECTION OUT OF CWA
SATURDAY NIGHT...THE ABSENCE OF A FOCUSING MECHANISM SUCH AS AN
OUTFLOW BOUNDARY OR MCV...SHOULD BE ENOUGH TO ALLOW THE CAP TO HOLD
KEEPING MOST OF THE DAY DRY ON SUNDAY. CONSENSUS POPS DO HAVE
CHANCE/SLIGHT CHANCE POPS IN THE NW 1/2 OF THE CWA WITH THE 12Z GEM
AND 00Z ECMWF BRINGING SFC TROUGH CLOSER TO CWA BY 00Z MONDAY THAN
GFS OR NAM. BETTER CHANCE OF PRECIPITATION...ESPECIALLY IN THE WEST
AS MODELS BRING SHORT WAVE...POSSIBLY CONVECTIVELY ENHANCED...
THROUGH THE AREA SUNDAY NIGHT INTO MONDAY. AS WITH TODAY...ANY
REMNANT CLOUD DEBRIS FROM OVERNIGHT CONVECTION COULD LIMIT DAYTIME
HEATING SUNDAY...BUT WITH LOW POPS AND EXPECTED 925 MB TEMPERATURES
FEEL A LEAN TOWARD WARMER GUIDANCE TEMPS IN LINE WITH LOW 90S. WITH
EXPECTED CONVECTION...UPPER 60S TO LOWER 70S LOW TEMPS SUNDAY NIGHT
TO BE FOLLOWED WITH HIGHS IN THE LOW TO MID 80S ON MONDAY.
LONG TERM...MONDAY NIGHT THROUGH FRIDAY. FORECAST CONFIDENCE LOW TO
MEDIUM.
MODELS AGREE THAT A SHORT WAVE/MCV DRIVEN COMPLEX WILL WILL UNDERCUT
THE RIDGE AND CROSS THE AREA MONDAY NIGHT INTO TUESDAY...WITH
ANOTHER SHORT WAVE ARRIVING TUESDAY AFTERNOON/EVENING DEPENDING ON
MODEL IN DEVELOPING PROGRESSIVE NEAR-ZONAL FLOW. YET ANOTHER
SHORT WAVE MOVES THROUGH WEDNESDAY AFTERNOON AHEAD OF DEEPER WAVE
THAT BEGINS TO DIG INTO THE NORTHERN LAKES REGION IN RESPONSE TO
AMPLIFYING RIDGE OVER THE WESTERN U.S. TIMING DIFFERENCES LEAD TO
POPS IN EVERY PERIOD... BUT DO EXPECT MORE EXPANSIVE DRY PERIODS
THAN THE CONSENSUS SOLUTIONS ARE GIVING. WITH SURFACE TROUGH HANGING
TO THE WEST...WILL STAY IN WARM HUMID AIR MASS THROUGH
WEDNESDAY...THEN SEE A GRADUAL COOL DOWN THURSDAY AND FRIDAY WITH
A CANADIAN AIR MASS WORKING IN BEHIND THE SURFACE LOW.
AVIATION/00Z TAFS/...GUSTY SOUTH TO SOUTHEAST WINDS WITH WAKE LOW WILL
CONTINUE TO WEAKEN OVER THE NEXT HOUR OR SO...WITH GUSTS TO
AROUND 20 KNOTS EXPECTED INTO EARLY THIS EVENING. DRY CONDITIONS
ARE EXPECTED THROUGH THE REST OF THIS AFTERNOON AND INTO THIS
EVENING ACROSS TAF SITES...WITH VFR CONDITIONS.
LEFT VFR CONDITIONS GOING THROUGH TONIGHT AND SATURDAY...AS
THUNDERSTORM CHANCES LINGER BUT LOW CONFIDENCE IN TIMING AND
PLACEMENT OF STORMS. MAY SEE MVFR VISIBILITIES WITH LIGHT FOG AT
SITES BETWEEN 09Z AND 14Z SATURDAY. MODEST SOUTH WINDS SHOULD LINGER
LATER TONIGHT INTO SATURDAY.
MARINE...
GUSTY SOUTH TO SOUTHEAST WINDS WITH WAKE LOW WILL LINGER FOR ANOTHER
HOUR OR SO BEFORE DIMINISHING. REFER TO LATEST SPECIAL MARINE
WARNINGS AND MARINE WEATHER STATEMENTS FOR MORE INFORMATION. BOATERS
SHOULD REMAIN IN SAFE HARBOR UNTIL THESE GUSTY WINDS SUBSIDE.
DEW POINTS RISING THROUGH THE 60S WILL OVERSPREAD THE COOL LAKE
WATERS TONIGHT INTO SATURDAY. WINDS WILL WEAKEN ENOUGH TO ALLOW FOR
FOG FORMATION LATER THIS EVENING INTO SATURDAY MORNING...BEFORE
MIXING OUT A BIT DURING THE AFTERNOON SATURDAY.
DENSE FOG IS POSSIBLE IF WINDS WEAKEN ENOUGH...SO WILL HAVE TO WATCH
TRENDS THIS EVENING. FOG MAY LINGER ON AND OFF THROUGH THE WEEKEND
INTO EARLY NEXT WEEK...AS LONG AS WINDS REMAIN LIGHT ENOUGH.
&&
.MKX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
LM...NONE.
&&
$$
UPDATE...DDV
TONIGHT/SATURDAY AND AVIATION/MARINE...WOOD
SATURDAY NIGHT THROUGH FRIDAY...REM
AREA FORECAST DISCUSSION
NWS GREEN BAY WI
848 PM CDT FRI JUN 21 2013
NEW INFORMATION ADDED TO UPDATE SECTION
.UPDATE...
ISSUED AT 829 PM CDT FRI JUN 21 2013
SMALL CLUSTER OF SVR TSTMS WITH DAMAGING WINDS NEAR MSP IS EXPECTED
TO MOVE ESE INTO CENTRAL WI LATER THIS EVG...FOLLOWING THE NORTHERN
PERIPHERY OF THE INSTABILITY/MOISTURE GRADIENT. THE STORMS SHOULD
ARRIVE IN CENTRAL WI BETWEEN 0330-0400Z. MARGINAL DAMAGING WINDS
AND BRIEF PERIODS OF TORRENTIAL RAINFALL WILL BE POSSIBLE IN OUR
SW COUNTIES LATE THIS EVG INTO THE EARLY MORNING HOURS OF
SATURDAY. WILL HAVE TO MONITOR HYDRO TRENDS OVER CENTRAL WI...
WHERE SOME LOCATIONS RECEIVED 1-2 INCHES OF RAIN OVER THE PAST
36 HOURS. WAA/ISENT LIFT SHOULD SUPPORT SCT SHRA/TSRA OVER AT
LEAST THE REST OF C/EC WI OVERNIGHT... AND THE REMNANTS OF THE
STRATIFORM PCPN SHIELD ASSOCIATED WITH THE MCV/MCS SHOULD MOVE
ACROSS N WI. WILL HAVE TO WATCH FOR WAKE LOW WINDS ON THE BACK
EDGE OF THE STRATIFORM PCPN SHIELD LATER TONIGHT. STRONG WAKE LOW
WINDS HAVE ALREADY BEEN REPORTED THIS EVG OVER E SD/SE ND/SW MN
THIS EVG...AND THE WAKE LOW GENERATION PARAMETER IS SHOWING
IMPRESSIVE VALUES TO AROUND 70 KTS IN WSTRN MN RIGHT NOW.
LOWERED MIN TEMPS A BIT OVER NORTHERN WI...WHERE A SHALLOW CANADIAN
AIR MASS CURRENTLY RESIDES.
&&
.SYNOPSIS...
ISSUED AT 241 PM CDT FRI JUN 21 2013
WARM AND HUMID WITH PLENTY OF RAIN.
THE WESTERLIES ACRS NOAM ARE SPLIT. WITHIN THE BRANCH OF THE FLOW
ACRS THE CONUS...UPR TROF WAS ACRS THE PAC NW...RIDGING EXTENDED
NWD ACRS THE PLAINS...AND A BROAD TROF WAS OVER ERN NOAM. THE UPR
FEATURES WL PROGRESS EWD A BIT EARLY IN THE FCST PERIOD...THEN A
MORE SIG ADJUSTMENT TO THE PATTERN WL TAKE PLACE NEXT WEEK...WHEN
THE MAIN FEATURES REFORM W OF THEIR CURRENT POSITIONS.
THE PATTERN FAVORS A WARM...HUMID...AND RAINY PATTERN FOR THE FCST
AREA. EXPECT NUMEROUS ROUNDS OF SHRA/TSRA AS SHRTWVS ROTG OUT OF
THE WRN TROF INTERACT WITH WARM HUMID AIR ACRS THE RGN. RAINFALL
TOTALS FOR THE PERIOD WL BE HIGH...AND POSSIBLY EXCESSIVE. THE
WARM HUMID AIR MASS WL RESULT IN ABV NORMAL TEMPS. READINGS ON
SOME OF THE DAYS COULD BE HELD DOWN IF THERE ARE WIDESPREAD CLDS
AND PCPN...BUT NIGHTTIME MINS WL PROBABLY HOLD WELL ABV NORMAL
LEVELS REGARDLESS.
&&
.SHORT TERM...TONIGHT AND SATURDAY
ISSUED AT 241 PM CDT FRI JUN 21 2013
THE LATEST RUC ANALYSIS AND SATELLITE/RADAR IMAGERY SHOW A
SHORTWAVE TROUGH MOVING EAST OVER THE UPPER PENINSULA. THE
CONVECTIVE COMPLEX TIED TO IT HAS SPLIT INTO TWO PIECES...ONE OVER
THE EASTERN UPPER PENINSULA AND THE OTHER OVER NORTHERN ILLINOIS.
STILL HAVE PLENTY OF CONVECTIVE DEBRIS ACROSS MUCH OF WISCONSIN
AND MINNESOTA EARLY THIS AFTERNOON...WHICH HAS HELD TEMPERATURES
BACK INTO THE 60S AND 70S. THE OUTFLOW BOUNDARY FROM THESE STORMS
HAS PUSHED ALL THE WAY INTO SOUTHERN IOWA AND CENTRAL ILLINOIS
WHERE STORMS ARE TRYING TO REFIRE. HOWEVER...OUR MAIN FORECAST
CONCERN REVOLVES AROUND THE SEVERE CONVECTION THAT HAS DEVELOPED
OVER SOUTH DAKOTA. THIS CONVECTION IS MOVING NORTHEAST AND ALREADY
APPEARS TO HAVE THE LOOK OF ANOTHER MCS. AS IT HEADS EAST...SEVERE
WEATHER CHANCES ARE THE MAIN FORECAST PRIORITY.
TONIGHT...THE SHORTWAVE TROUGH WILL LIFT NE TONIGHT AS MID-LEVEL
RIDGING STRENGTHENS OVER THE MISSISSIPPI VALLEY. AHEAD OF THIS
SHORTWAVE TROUGH AND ASSOCIATED SURFACE LOW...A LLJ WILL DEVELOP
AND PUSH AN 850MB WARM FRONT NORTH INTO SOUTHERN OR CENTRAL
MINNESOTA AND CENTRAL WISCONSIN. CONVECTION SHOULD BECOME ROOTED
TO THIS BOUNDARY...AS FORCING ALONG THE NOSE OF THE LLJ AND
INSTABILITY OF 1K-2K J/KG ALONG THIS FRONT SHOULD BE ABLE TO
SUSTAIN STORMS. THE 12Z MODELS HAVE A VARIETY OF SOLUTIONS OF HOW
FAR NORTH THIS FRONT REACHES WHICH OBVIOUSLY IMPACTS THE CHANCES
OF THE CONVECTION MOVING INTO THE REGION. THE LLJ WILL BE VEERING
AFTER MIDNIGHT WHICH SHOULD CAUSE THE MCS TO TURN TO THE
SOUTHEAST. SO IF THIS COMPLEX CONTINUES ON ITS ENE HEADING TOWARDS
CENTRAL MINNESOTA...IT WILL HAVE A GREATER CHANCE OF REACHING
CENTRAL WISCONSIN LATE TONIGHT AND NORTHEAST WISCONSIN IN THE
MORNING. THOUGH THE STORMS WILL BE WEAKENING AS THEY MOVE INTO
WISCONSIN...THE SQUALL LINE WILL HAVE POTENTIAL TO CREATE DAMAGING
WINDS AND SMALL HAIL...AS WELL AS ANOTHER INCH TO INCH AND A HALF
OF RAINFALL. HAVE REORIENTATED POPS TO SHOW HIGHER VALUES OVER
CENTRAL AND EAST-CENTRAL WISCONSIN AFTER MIDNIGHT...AND ANTICIPATE
MUCH IF NOT ALL OF THE AREA WILL BE DRY UNTIL THEN. MUGGY LOWS IN
THE 60S.
SATURDAY...ANTICIPATE CONVECTION TO BE MOVING THROUGH THE AREA AT
LEAST FOR THE FIRST HALF OF THE MORNING. THE COLD POOL FROM THE
CONVECTION SHOULD SUPPRESS THE SURFACE WARM FRONT TO THE SOUTH.
LIKE TODAY...SHOULD SEE A LULL IN THE CONVECTION ONCE THE MCS
DEPARTS (IF IT REACHES HERE). THEN SHORTWAVES MOVING TOWARDS
WESTERN LAKE SUPERIOR AND A SURFACE LOW OVER CENTRAL MINNESOTA
SHOULD HELP THE WESTERN PART OF THE WARM FRONT LIFT NORTH INTO
NORTHWEST OR CENTRAL WISCONSIN. PROGGED SOUNDINGS INDICATE AROUND
2K J/KG OF ML CAPE OVER NORTH-CENTRAL WISCONSIN THOUGH 0-6KM SHEAR
IS ONLY AROUND 25-30KTS. CANNOT RULE OUT A SEVERE THREAT RE-
DEVELOPING IN THE AFTERNOON IF THERE IS SUFFICIENT SURFACE
HEATING. DAMAGING WINDS AND LARGE HAIL WOULD BE THE MAIN THREATS.
.LONG TERM...SATURDAY NIGHT THROUGH FRIDAY
ISSUED AT 241 PM CDT FRI JUN 21 2013
THOUGH THE OVERALL EVOLUTION OF THE WEATHER PATTERN AND BASIC
WEATHER FORECAST ARE FAIRLY CLEAR CUT...IT REMAINS EXTREMELY
DIFFICULT TO ADD DETAIL BEYOND THE SHORT-TERM PORTION OF THE
FORECAST. THERE IS REALLY NO GETTING AROUND CARRYING A CHC OF
TSTMS THROUGH MOST OF THE PERIOD.
GIVEN THE LIKELIHOOD OF SEVERAL ROUNDS OF SHRA/TSRA...THE MAIN
HAZARD SEEMS TO BE HEAVY RAIN AND POSSIBLE FLOODING. BUT WL
PROBABLY HAVE A FEW ROUNDS OF SVR/NR SVR WX AS WELL. HUNCH HERE IS
THAT GREATEST SVR THREAT DURING THE PERIOD WL ACTUALLY HOLD OFF
UNTIL NEXT WK WHEN UPR RIDGE STARTS TO REFORM FARTHER W...AND UPR
FLOW ACRS THE FCST AREA STARTS STRENGTHEN FM THE WNW. WL MENTION
THE POTENTIAL FOR HEAVY RAINS AND SVR WX IN THE HWO...AND ISSUE AN
ESF TO FURTHER HILIGHT THE POTENTIAL FOR FLOODING.
&&
.AVIATION...FOR 00Z TAF ISSUANCE
ISSUED AT 642 PM CDT FRI JUN 21 2013
CONFIDENCE IS LOW IN THE DETAILS FOR TONIGHT INTO SATURDAY...
BUT SOME GENERAL TRENDS APPEAR TO BE SETTING UP. THUNDERSTORMS
OVER CENTRAL MINNESOTA SHOULD FOLLOW THE MOISTURE AND INSTABILITY
GRADIENT AND TURN TOWARD CENTRAL WI THIS EVENING. EXTRAPOLATION
SUGGESTS AN ARRIVAL TIME AROUND 05Z AT THE WESTERN TAF SITES...
AND GIVEN THE UNCERTAINTY IN THE TRACK...WILL HAVE A TEMPO GROUP
FOR RHI/AUW/CWA AFTER 05Z. IF THE STORMS MAINTAIN THEIR
INTENSITY...GUSTY WINDS AND TORRENTIAL RAINFALL WILL BE A GOOD
BET. WILL NEED TO WATCH FOR A BRIEF PERIOD OF STRONG EASTERLY
WINDS BEHIND THE MAIN TSTM COMPLEX (DUE TO A WAKE LOW)...LIKE WE
EXPERIENCED FRIDAY MORNING. WILL LIKELY HAVE MVFR/IFR CONDITIONS
WITH THE TSTMS...THEN A PERIOD OF LINGERING LOW CLOUDS AND VSBYS
(IN FOG) AFTER THE RAIN ENDS. IMPROVING CONDITIONS ARE EXPECTED BY
MID TO LATE SAT MORNING...WITH SCT TSTMS REDEVELOPING DURING THE
MID TO LATE AFTERNOON.
&&
.GRB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE.........KIECKBUSCH
SYNOPSIS.......SKOWRONSKI
SHORT TERM.....MPC
LONG TERM......SKOWRONSKI
AVIATION.......KIECKBUSCH
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
642 PM CDT FRI JUN 21 2013
.SHORT TERM...(THIS EVENING THROUGH SATURDAY)
ISSUED AT 355 PM CDT FRI JUN 21 2013
AT 3 PM...A THUNDERSTORM COMPLEX WAS LOCATED OVER EASTERN SOUTH
DAKOTA. THE HRRR SEEMS TO BE HANDLING THIS SYSTEM THE BEST THIS
AFTERNOON. IT SHOWS THAT THIS SYSTEM WILL MOVE NORTHEAST INTO
NORTHEAST SOUTH DAKOTA AND WEST CENTRAL MINNESOTA LATE THIS
AFTERNOON AND EARLY EVENING. THIS SYSTEM IS INITIALLY FOLLOWING THE
SHORT WAVE TROUGH. HOWEVER AS THE LOW LEVEL JET STRENGTHENS THIS
EVENING AND STRONG 850 MB MOISTURE TRANSPORT WILL MOVE INTO THE
FORECAST AREA. EXPECT SOME DEVELOPMENT ALONG THE ADVANCING WARM
FRONT ON THE SOUTH OF THIS PERIPHERY OF THIS SYSTEM. MLCAPES ALONG
THIS BOUNDARY CLIMB TO AROUND 5000 J/KG LATE THIS AFTERNOON AND
THEN CONTINUES INTO THE EARLY EVENING. WHILE THE 0-6 KM SHEAR IS
NOT FAVORABLE FOR SUPERCELLS...THE 0-3 KM BULK SHEAR IS OVER
40 KNOTS AND IT WILL BE FAVORABLE FOR DAMAGING WINDS. IN ADDITION
WITH DCAPES OVER 1500 J/KG...THIS WOULD ALSO MAKE IT FAVORABLE FOR
THE STORMS TO PRODUCE DAMAGING WINDS. CURRENTLY EXPECTING THE
CURRENT CONVECTION TO EVOLVE INTO 1 OR MORE BOW ECHOS AS THEY
BECOME MORE COLD POOL DOMINANT...AND THESE LINES WOULD LIKELY MOVE
ALONG OR NORTH OF THE INTERSTATE 90 CORRIDOR BETWEEN 22.03Z AND
22.09Z. HOWEVER IF THE BOUNDARY DOES NOT LIFT AS FAR NORTH AS THE
MESO MODELS INDICATE...THIS CONVECTION COULD POTENTIALLY BE
FURTHER SOUTH TONIGHT.
FLASH FLOODING IS ALSO A CONCERN TONIGHT AS WARM CLOUD LAYER
DEPTHS CLIMB INTO THE 4 TO 4.5 KM RANGE AND PRECIPITABLE WATER
VALUES CLIMB INTO THE 1.8 TO 2.0 INCH RANGE. WITH THE LOW LEVEL
JET CONTINUING TO IMPINGE ON THE FRONT NEAR THE MINNESOTA AND IOWA
BORDER...EXPECT CONVECTION TO CONTINUE TO DEVELOP ACROSS EASTERN
NEBRASKA...WESTERN IOWA AND SOUTHWEST MINNESOTA THROUGHOUT THE
NIGHT. THIS CONVECTION WOULD THEN TRAIN INTO THE FORECAST AREA
WITH THE MEAN WIND. WOULD NOT BE SHOCKED TO SEE 3 TO 5 INCHES OF
RAIN FALL ACROSS PARTS OF THE AREA TONIGHT. THERE MAY BE EVEN SOME
LOCALLY HIGHER AMOUNTS. THIS LOOKS LIKE A CLASSIC MADDOX WARM
FRONTAL FLASH FLOOD EVENT. DUE TO THIS...ISSUED A FLASH FLOOD
WATCH FOR TONIGHT AND SATURDAY MORNING. THE SHOWERS AND
THUNDERSTORMS WILL GRADUALLY DIMINISH ON SATURDAY MORNING AS THE
LOW LEVEL JET WEAKENS.
ON SATURDAY AFTERNOON...THE MODELS SHOW THAT THE WARM FRONT WILL MOVE
NORTHWARD TOWARD THE INTERSTATE 94 CORRIDOR. WITH THERE NOT MUCH
MOISTURE CONVERGENCE ALONG THIS FRONT AND SOME CAPPING
ALOFT...THERE IS A POTENTIAL THAT THE COULD BE SOME DRY HOURS.
.LONG TERM...(SATURDAY NIGHT THROUGH FRIDAY)
ISSUED AT 355 PM CDT FRI JUN 21 2013
ON SATURDAY NIGHT...MANY OF THE DETERMINISTIC MODELS SUGGEST THAT
THE 850 MB MOISTURE TRANSPORT WILL SHIFT NORTHEAST OF THE AREA BY
LATE EVENING. AS A RESULT...MANY OF THESE MODELS HAS THE FORECAST
AREA DRYING OUT DURING THE 23.06Z TO 23.12Z TIME FRAME. IF THIS
TREND CONTINUES...MAY HAVE TO LOWER OR POSSIBLY TAKE THESE
PRECIPITATION CHANCES OUT OF THE FORECAST.
FROM SUNDAY INTO TUESDAY...THE MODELS CONTINUE TO STRUGGLE WITH
THE LOCATION OF THE FRONT AND WHERE MESOSCALE COMPLEXES MAY
DEVELOP. AS A RESULT...THE FORECAST CONFIDENCE FOR THE TIMING AND
LOCATION OF THE PRECIPITATION IS NOT AS CERTAIN. DUE TO
THIS...STAYED WITH THE CONSALL PRECIPITATION CHANCES AND ALSO WITH
THEIR MAXIMUM AND MINIMUM TEMPERATURES. ON ANY OF THESE
DAYS...TEMPERATURES COULD EASILY CLIMB INTO THE LOWER 90S IF
ENOUGH SUNSHINE CAN OCCUR.
FROM WEDNESDAY INTO FRIDAY...THE DETERMINISTIC MODELS ARE SHOWING
THAT THE UPPER LEVEL RIDGE WILL RETROGRADE INTO THE WESTERN UNITED
STATES AND WESTERN CANADA. THIS IS IN RESPONSE TO A MODERATE
MADDEN JULIAN OSCILLATION MOVING TOWARD THE INTERNATIONAL DATELINE.
WHEN THIS OCCURS IN SUMMER...CLIMATE PREDICTION CENTER COMPOSITES
FAVOR ABOVE NORMAL TEMPERATURE ANOMALIES ACROSS THE WESTERN UNITED
STATES. AS A RESULT...CONFIDENCE IS HIGH THAT THIS WILL
OCCUR...BUT THE EXACT TIME WHEN THIS WILL ULTIMATELY TAKE PLACE IS
STILL A BIT UNCERTAIN.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z SATURDAY EVENING)
ISSUED AT 642 PM CDT FRI JUN 21 2013
A COUPLE ROUNDS OF SHOWERS/THUNDERSTORMS COULD IMPACT THE TAF
SITES THROUGH EARLY SATURDAY MORNING. CURRENTLY WATCHING
CONVECTION ALONG THE I-35 CORRIDOR...WITH THE STRONGEST COMPLEX
NEARING THE TWIN CITIES. THE CORE OF THE CONVECTION WILL LIKELY
MISS KRST/KLSE TO THE NORTH...BUT SOME DEVELOPMENT ON THE SOUTH
END WILL LIKELY IMPACT KRST BY 01Z...MORE UNSURE ABOUT KLSE. EXPECTING
A LULL IN ACTIVITY POST THIS INITIAL WAVE...BEFORE REDEVELOPMENT
ASSOCIATED WITH THE EVENING LLJ AROUND 05Z. THESE STORMS COULD
TRACK MORE FAVORABLY ACROSS SOUTHEAST MINNESOTA INTO WESTERN
WISCONSIN TO IMPACT KRST/KLSE. ACTIVITY SHOULD WANE/EXIT SATURDAY
MORNING. BULK OF SATURDAY MORNING INTO EARLY AFTERNOON AREA WILL
BE CAPPED BUT MORE SHOWERS/THUNDERSTORMS POSSIBLE BY MID/LATE
AFTERNOON THOUGH UNCERTAINTY EXISTS ON WHERE THIS WILL OCCUR.
&&
.HYDROLOGY...TONIGHT INTO SATURDAY
ISSUED AT 355 PM CDT FRI JUN 21 2013
OVERNIGHT 1 TO 2 INCHES OF RAIN FELL ACROSS SOUTHEAST
MINNESOTA...AND WEST CENTRAL AND NORTH CENTRAL WISCONSIN...AND
2 TO 4 INCHES FELL ACROSS NORTHEAST IOWA...AND SOUTHWEST AND
CENTRAL WISCONSIN. THIS CAUSED RIVER FLOOD WARNINGS TO BE ISSUED
ALONG THE BLACK AND KICKAPOO RIVERS IN WESTERN WISCONSIN. AS A
STRONG LOW LEVEL JET BRINGS ABUNDANT MOISTURE INTO THE AREA
TONIGHT. EXPECT THAT 3 TO 5 INCHES MAY FALL ACROSS PARTS OF THE
AREA TONIGHT. A FEW LOCAL SPOTS MAY SEE EVEN HIGHER AMOUNTS.
THINKING THAT THE BEST CHANCES ARE ALONG AND NORTH OF THE
INTERSTATE 90 CORRIDOR. HOWEVER THERE IS STILL SOME UNCERTAINTY IN
THIS. THIS ADDITIONAL RAIN WILL LIKELY RESULT IN SOME FLASH
FLOODING TONIGHT. AS A RESULT...WENT WITH A FLASH FLOOD WATCH FOR
THE ENTIRE AREA TONIGHT.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...FLASH FLOOD WATCH THROUGH SATURDAY MORNING FOR WIZ017-029-
032>034-041>044-053>055-061.
MN...FLASH FLOOD WATCH THROUGH SATURDAY MORNING FOR MNZ079-086>088-
094>096.
IA...FLASH FLOOD WATCH THROUGH SATURDAY MORNING FOR IAZ008>011-018-
019-029-030.
&&
$$
SHORT TERM...BOYNE
LONG TERM...BOYNE
AVIATION...ZT
HYDROLOGY...BOYNE
FORECAST DISCUSSION FOR ROUTINE AFTERNOON FORECAST ISSUANCE
.SYNOPSIS...
ISSUED AT 241 PM CDT FRI JUN 21 2013
WARM AND HUMID WITH PLENTY OF RAIN.
THE WESTERLIES ACRS NOAM ARE SPLIT. WITHIN THE BRANCH OF THE FLOW
ACRS THE CONUS...UPR TROF WAS ACRS THE PAC NW...RIDGING EXTENDED
NWD ACRS THE PLAINS...AND A BROAD TROF WAS OVER ERN NOAM. THE UPR
FEATURES WL PROGRESS EWD A BIT EARLY IN THE FCST PERIOD...THEN A
MORE SIG ADJUSTMENT TO THE PATTERN WL TAKE PLACE NEXT WEEK...WHEN
THE MAIN FEATURES REFORM W OF THEIR CURRENT POSITIONS.
THE PATTERN FAVORS A WARM...HUMID...AND RAINY PATTERN FOR THE FCST
AREA. EXPECT NUMEROUS ROUNDS OF SHRA/TSRA AS SHRTWVS ROTG OUT OF
THE WRN TROF INTERACT WITH WARM HUMID AIR ACRS THE RGN. RAINFALL
TOTALS FOR THE PERIOD WL BE HIGH...AND POSSIBLY EXCESSIVE. THE
WARM HUMID AIR MASS WL RESULT IN ABV NORMAL TEMPS. READINGS ON
SOME OF THE DAYS COULD BE HELD DOWN IF THERE ARE WIDESPREAD CLDS
AND PCPN...BUT NIGHTTIME MINS WL PROBABLY HOLD WELL ABV NORMAL
LEVELS REGARDLESS.
&&
.SHORT TERM...TONIGHT AND SATURDAY
ISSUED AT 241 PM CDT FRI JUN 21 2013
THE LATEST RUC ANALYSIS AND SATELLITE/RADAR IMAGERY SHOW A
SHORTWAVE TROUGH MOVING EAST OVER THE UPPER PENINSULA. THE
CONVECTIVE COMPLEX TIED TO IT HAS SPLIT INTO TWO PIECES...ONE OVER
THE EASTERN UPPER PENINSULA AND THE OTHER OVER NORTHERN ILLINOIS.
STILL HAVE PLENTY OF CONVECTIVE DEBRIS ACROSS MUCH OF WISCONSIN
AND MINNESOTA EARLY THIS AFTERNOON...WHICH HAS HELD TEMPERATURES
BACK INTO THE 60S AND 70S. THE OUTFLOW BOUNDARY FROM THESE STORMS
HAS PUSHED ALL THE WAY INTO SOUTHERN IOWA AND CENTRAL ILLINOIS
WHERE STORMS ARE TRYING TO REFIRE. HOWEVER...OUR MAIN FORECAST
CONCERN REVOLVES AROUND THE SEVERE CONVECTION THAT HAS DEVELOPED
OVER SOUTH DAKOTA. THIS CONVECTION IS MOVING NORTHEAST AND ALREADY
APPEARS TO HAVE THE LOOK OF ANOTHER MCS. AS IT HEADS EAST...SEVERE
WEATHER CHANCES ARE THE MAIN FORECAST PRIORITY.
TONIGHT...THE SHORTWAVE TROUGH WILL LIFT NE TONIGHT AS MID-LEVEL
RIDGING STRENGTHENS OVER THE MISSISSIPPI VALLEY. AHEAD OF THIS
SHORTWAVE TROUGH AND ASSOCIATED SURFACE LOW...A LLJ WILL DEVELOP
AND PUSH AN 850MB WARM FRONT NORTH INTO SOUTHERN OR CENTRAL
MINNESOTA AND CENTRAL WISCONSIN. CONVECTION SHOULD BECOME ROOTED
TO THIS BOUNDARY...AS FORCING ALONG THE NOSE OF THE LLJ AND
INSTABILITY OF 1K-2K J/KG ALONG THIS FRONT SHOULD BE ABLE TO
SUSTAIN STORMS. THE 12Z MODELS HAVE A VARIETY OF SOLUTIONS OF HOW
FAR NORTH THIS FRONT REACHES WHICH OBVIOUSLY IMPACTS THE CHANCES
OF THE CONVECTION MOVING INTO THE REGION. THE LLJ WILL BE VEERING
AFTER MIDNIGHT WHICH SHOULD CAUSE THE MCS TO TURN TO THE
SOUTHEAST. SO IF THIS COMPLEX CONTINUES ON ITS ENE HEADING TOWARDS
CENTRAL MINNESOTA...IT WILL HAVE A GREATER CHANCE OF REACHING
CENTRAL WISCONSIN LATE TONIGHT AND NORTHEAST WISCONSIN IN THE
MORNING. THOUGH THE STORMS WILL BE WEAKENING AS THEY MOVE INTO
WISCONSIN...THE SQUALL LINE WILL HAVE POTENTIAL TO CREATE DAMAGING
WINDS AND SMALL HAIL...AS WELL AS ANOTHER INCH TO INCH AND A HALF
OF RAINFALL. HAVE REORIENTATED POPS TO SHOW HIGHER VALUES OVER
CENTRAL AND EAST-CENTRAL WISCONSIN AFTER MIDNIGHT...AND ANTICIPATE
MUCH IF NOT ALL OF THE AREA WILL BE DRY UNTIL THEN. MUGGY LOWS IN
THE 60S.
SATURDAY...ANTICIPATE CONVECTION TO BE MOVING THROUGH THE AREA AT
LEAST FOR THE FIRST HALF OF THE MORNING. THE COLD POOL FROM THE
CONVECTION SHOULD SUPPRESS THE SURFACE WARM FRONT TO THE SOUTH.
LIKE TODAY...SHOULD SEE A LULL IN THE CONVECTION ONCE THE MCS
DEPARTS (IF IT REACHES HERE). THEN SHORTWAVES MOVING TOWARDS
WESTERN LAKE SUPERIOR AND A SURFACE LOW OVER CENTRAL MINNESOTA
SHOULD HELP THE WESTERN PART OF THE WARM FRONT LIFT NORTH INTO
NORTHWEST OR CENTRAL WISCONSIN. PROGGED SOUNDINGS INDICATE AROUND
2K J/KG OF ML CAPE OVER NORTH-CENTRAL WISCONSIN THOUGH 0-6KM SHEAR
IS ONLY AROUND 25-30KTS. CANNOT RULE OUT A SEVERE THREAT RE-
DEVELOPING IN THE AFTERNOON IF THERE IS SUFFICIENT SURFACE
HEATING. DAMAGING WINDS AND LARGE HAIL WOULD BE THE MAIN THREATS.
.LONG TERM...SATURDAY NIGHT THROUGH FRIDAY
ISSUED AT 241 PM CDT FRI JUN 21 2013
THOUGH THE OVERALL EVOLUTION OF THE WEATHER PATTERN AND BASIC
WEATHER FORECAST ARE FAIRLY CLEAR CUT...IT REMAINS EXTREMELY
DIFFICULT TO ADD DETAIL BEYOND THE SHORT-TERM PORTION OF THE
FORECAST. THERE IS REALLY NO GETTING AROUND CARRYING A CHC OF
TSTMS THROUGH MOST OF THE PERIOD.
GIVEN THE LIKELIHOOD OF SEVERAL ROUNDS OF SHRA/TSRA...THE MAIN
HAZARD SEEMS TO BE HEAVY RAIN AND POSSIBLE FLOODING. BUT WL
PROBABLY HAVE A FEW ROUNDS OF SVR/NR SVR WX AS WELL. HUNCH HERE IS
THAT GREATEST SVR THREAT DURING THE PERIOD WL ACTUALLY HOLD OFF
UNTIL NEXT WK WHEN UPR RIDGE STARTS TO REFORM FARTHER W...AND UPR
FLOW ACRS THE FCST AREA STARTS STRENGTHEN FM THE WNW. WL MENTION
THE POTENTIAL FOR HEAVY RAINS AND SVR WX IN THE HWO...AND ISSUE AN
ESF TO FURTHER HILIGHT THE POTENTIAL FOR FLOODING.
&&
.AVIATION...FOR 18Z TAF ISSUANCE
ISSUED AT 1224 PM CDT FRI JUN 21 2013
CONFIDENCE IS STILL RATHER LOW IN THE DETAILS FOR LATE TONIGHT
INTO SATURDAY. THUNDERSTORMS OVER SOUTH DAKOTA ARE EXPECTED TO
CONTINUE TO HEAD EAST THROUGH THE REST OF THE AFTERNOON AND
EVENING. SOME OF THE NEWEST GUIDANCE SUPPORTS THIS CLUSTER TO HEAD
TOWARDS CENTRAL WISCONSIN LATE TONIGHT AND THEN THE FOX VALLEY
TOMORROW MORNING. HOWEVER...PLENTY OF OTHER GUIDANCE WOULD ALSO
SUPPORT THIS CLUSTER HEADING FROM SOUTHERN MINNESOTA INTO
SOUTHWEST WISCONSIN...THEREBY MISSING THE TAF SITES ENTIRELY.
TAKING THE MIDDLE OF THE ROAD APPROACH YIELDS A FORECAST WHERE
CENTRAL WISCONSIN AND THE FOX VALLEY RECEIVE SHOWERS AND
STORMS...BUT THE STRONGEST STORMS STAY SOUTH OF THE TAF SITES.
ONCE THE STORMS PASS IN THE MORNING...SHOULD SEE A BRIEF PERIOD OF
QUIETER WEATHER.
&&
.GRB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS.......SKOWRONSKI
SHORT TERM.....MPC
LONG TERM......SKOWRONSKI
AVIATION.......MPC
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
316 PM CDT THU JUN 20 2013
.SHORT TERM...(TONIGHT THROUGH SUNDAY)
ISSUED AT 316 PM CDT THU JUN 20 2013
MAIN FORECAST CONCERNS ARE PRECIPITATION CHANCES AND POTENTIAL
SEVERE WITH THUNDERSTORMS THROUGH PERIOD.
LATEST WATER VAPOR SATELLITE IMAGERY SHOWING WEAK SHORTWAVE TROUGH
LIFTING NORTHEAST INTO NORTH CENTRAL WISCONSIN AND A SERIES OF
SHORTWAVE TROUGHS OVER LAKE SUPERIOR WESTWARD TO NORTH DAKOTA. LATEST
MOSAIC RADAR INDICATES SHOWERS AND THUNDERSTORMS ACROSS NORTHERN
WISCONSIN INTO EASTERN NORTH DAKOTA. THIS IS IN RESPONSE TO 925-850MB
MOISTURE TRANSPORT AND NOSE OF LOW LEVEL JET PER 20.15Z RAP.
THE 20.12Z GFS/NAM CONTINUE TO BE IN GOOD AGREEMENT IN CARVING
UPPER LEVEL TROUGH OVER THE WESTERN UNITED STATES AND EJECTING
OUT A SERIES OF SHORTWAVE TROUGHS EMBEDDED IN SOUTHWESTERLY
FLOW ALOFT INTO THE NORTHERN PLAINS AND UPPER GREAT LAKES
REGION OVER THE NEXT SEVERAL DAYS. BIGGEST DIFFERENCES REMAIN ARE
THE TIMING AND PLACEMENT OF THE SHORTWAVE TROUGHS OVER
THE UPPER GREAT LAKES REGION THROUGH THE PERIOD. THE DETERMINISTIC
MODELS ARE OKAY IN AGREEMENT WITH SURFACE FRONT PLACEMENT THROUGH 12Z
SATURDAY...THEN THE 20.12Z NAM PUSHES SURFACE FRONT FARTHER SOUTH
THAN THE GFS. CONFIDENCE IN FORECAST BEGINS TO LOWER AFTER 12Z
SATURDAY.
TONIGHT INTO FRIDAY...THE 20.12Z GFS/NAM AND 20.15Z RAP ALL
INDICATING DECENT 925-850MB MOISTURE TRANSPORT AND LOW LEVEL JET TO
INCREASE THIS EVENING OVER FORECAST AREA. WITH A SERIES OF SHORTWAVE
TROUGHS OVER THE NORTHERN PLAINS...HIGH RESOLUTION MODELS OF THE
20.12Z SPC WRF...20.12Z ARW-EAST AND 20.16Z HRRR SHOW A COMPLEX OF
THUNDERSTORMS OVER EASTERN NORTH DAKOTA AND NORTHERN SOUTH DAKOTA
ON THE NOSE OF THE LOW LEVEL JET/925-850MB MOISTURE TRANSPORT...TO
MOVE EAST-SOUTHEAST INTO THE NORTHERN PORTIONS OF THE FORECAST AREA
AROUND 09Z TO 12Z. THE 20.12Z GFS/NAM INDICATE SOME SORT OF COMPLEX
OF THUNDERSTORMS TO TRACK INTO THE NORTHERN PORTIONS OF THE FORECAST
AREA. CONFIDENCE IS INCREASING A COMPLEX OF THUNDERSTORMS WILL MOVE
INTO THE NORTHERN PORTIONS OF THE FORECAST AREA. SEVERE POTENTIAL
STILL EXIST WITH THE 20.12Z GFS/NAM SHOW 0-3KM SHEAR OF 25-35 KNOTS
AND 0-6KM MOST UNSTABLE CAPE OF 1000-2000 J/KG OVER NORTHERN
PORTIONS OF FORECAST AREA 06Z-12Z FRIDAY. THE COMPLEX OF STORMS
SHOULD DEVELOP INTO A LINE/SQUALL LINE OF STORMS OVERNIGHT AND HAVE
THE POTENTIAL FOR DAMAGING WINDS ACROSS THE NORTHERN PORTIONS OF THE
FORECAST AREA.
FRIDAY NIGHT INTO SUNDAY...ACTIVE WEATHER PATTERN CONTINUES...AS
THE 20.12Z GFS/NAM CONTINUE TO INDICATE A SERIES OF SHORTWAVE
TROUGHS TO MOVE INTO THE UPPER MIDWEST AND UPPER GREAT LAKES
REGION. THE 20.12Z GFS/NAM CONTINUE TO HAVE DIFFERENCES IN TIMING
AND PLACEMENT OF THE SHORTWAVE TROUGHS/SURFACE FRONT ACROSS THE
UPPER MIDWEST AND GREAT LAKES REGION. THE DETERMINISTIC MODELS DO
SHOW 20 TO 30 KNOTS OF 0-3KM WIND SHEAR AND ELEVATED CAPE OF A 2000-
3000 J/KG FRIDAY THROUGH 06Z SATURDAY. POTENTIAL IS THERE FOR
THUNDERSTORMS TO BECOME SEVERE WITH THE MAIN THREAT TO BE DAMAGING
WINDS. HOWEVER...THE DETERMINISTIC MODELS ARE FOCUSING THE BEST
CHANCES FOR CONVECTION TO AFFECT MAINLY THE NORTHERN HALF OF THE
FORECAST AREA THROUGH SUNDAY...WITH THE 20.12Z GFS SUGGESTING MUCH OF
THE CONVECTION TO BE NORTH AND NORTHWEST OF THE FORECAST AREA.
CONFIDENCE IN FORECAST REMAINS LOW FRIDAY NIGHT INTO SUNDAY.
.LONG TERM...(SUNDAY NIGHT THROUGH THURSDAY)
ISSUED AT 316 PM CDT THU JUN 20 2013
MAIN FORECAST CONCERNS ARE PRECIPITATION CHANCES THROUGH THE PERIOD.
THE 20.12Z GFS/NAM/GEM ARE IN AGREEMENT IN EJECTING OUT A
COUPLE OF SHORTWAVE TROUGHS INTO THE UPPER MIDWEST THROUGH 00Z
WEDNESDAY...THEN MODELS BEGIN TO DIG UPPER LEVEL TROUGH OVER THE
GREAT LAKES REGION AND DEVELOP NORTHWEST FLOW ALOFT OVER FORECAST
AREA WEDNESDAY INTO THURSDAY. WITH ENOUGH LIFT AND MOISTURE IN
ASSOCIATION WITH SHORTWAVE TROUGHS WILL CONTINUE WITH SMALL CHANCES
OF PRECIPITATION THROUGH MUCH OF THE PERIOD. TEMPERATURES THROUGH
12Z WEDNESDAY WILL BE ABOVE NORMAL...AS THE DETERMINISTIC MODELS
ADVECT WARMER AIR ALOFT INTO FORECAST AREA MONDAY INTO
TUESDAY. THE 20.12Z GFS/ECMWF ARE SHOWING 925MB TEMPERATURES PLUS 24
TO 27 DEGREES CELSIUS BY 00Z WEDNESDAY AND THE 20.00Z GEFS
INDICATE STANDARDIZED ANOMALIES OF 1-1.5 ABOVE NORMAL. THIS WILL
ALLOW TEMPERATURES TO CLIMB INTO THE UPPER 80S TO POSSIBLY
INTO THE MIDDLE 90S ACROSS FORECAST AREA. COOLER AIR WILL FILTER
INTO THE FORECAST BEHIND SURFACE LOW/SHORTWAVE TROUGH WEDNESDAY INTO
THURSDAY.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z FRIDAY AFTERNOON)
ISSUED AT 105 PM CDT THU JUN 20 2013
AN AREA OF SHOWERS AND THUNDERSTORMS WILL CONTINUE TO MOVE THROUGH
NORTH CENTRAL WISCONSIN THIS AFTERNOON. ADDITIONAL SCATTERED
SHOWERS AND THUNDERSTORMS WILL POSSIBLE THIS AFTERNOON MAINLY
ALONG AND NORTH OF THE INTERSTATE 90 CORRIDOR. THIS PRECIPITATION
WAS FAR UNCERTAIN TO BE ADDED INTO THE TAFS AT THIS TIME. FOR THIS
EVENING...THE 20.14Z HRRR SUGGESTED THAT A BOW ECHO WOULD AFFECT
THE TAF SITES BETWEEN 21.02Z AND 21.04Z. HOWEVER THE 20.15Z HAS
BACKED AWAY FROM THIS SOLUTION AND NOW HAS AN AREA OF
THUNDERSTORMS MOVING ACROSS EAST-CENTRAL MINNESOTA AND CENTRAL
WISCONSIN. MEANWHILE THE 20.12Z NMM AND ARW ARE IN AGREEMENT THAT
A SQUALL LINE WILL MOVE THROUGH THE TAF SITES BETWEEN 21.07Z AND
21.10Z. SINCE THERE IS ALREADY A LINE DEVELOPING OVER NORTH DAKOTA...
OPTED TO GO MORE WITH THESE SOLUTIONS IN THE TAFS. THERE COULD
POTENTIALLY BE SOME BRIEF WIND GUSTS IN THE 40 TO 50 MPH RANGE.
HOWEVER WITH THERE SOME UNCERTAINTY ON HOW STRONG THE LINE WILL BE
WHEN IT MOVES THROUGH OUR AREA...JUST OPTED TO GO WITH WIND GUSTS
UP TO 30 MPH FOR NOW.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...DTJ
LONG TERM....DTJ
AVIATION.....BOYNE
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
105 PM CDT THU JUN 20 2013
.SHORT TERM...(TODAY THROUGH SATURDAY NIGHT)
ISSUED AT 250 AM CDT THU JUN 20 2013
HEAT...HUMIDITY...AND FUEL FOR THUNDERSTORM COMPLEXES WILL USHER IN
THE OFFICIAL START TO SUMMER DURING THE SHORT TERM. NEARLY
IMPOSSIBLE CHALLENGE WITH CURRENT FORECAST IS TRYING TO TIME AND
PLACE INEVITABLE MESOSCALE CONVECTIVE SYSTEMS INTO THIS WEEKEND.
TIMING OF ANY FEATURE DIFFICULT PAST 24 HOURS AND THIS IS
ILLUSTRATED WELL IN SHORT TERM AND MESOSCALE MODELS THAT SEEM TO
SHIFT SOLUTIONS EVERY RUN.
LARGE UPPER TROUGH OVER NORTHWEST U.S. AND EJECTING SHORT WAVE
ENERGY INTO INTERMOUNTAIN WEST HAS GENERATED ENOUGH RESPONSE IN THE
FORM OF LOW LEVEL JET AND MOISTURE RETURN WHICH WILL SET THE STAGE
FOR ACTIVE SEVERAL DAYS ACROSS THE NORTHERN STATES. ALREADY SEEING
CLUSTERS OF STORMS FROM CENTRAL MINNESOTA BACK INTO NORTH DAKOTA
THIS MORNING IN AREA OF FAVORED MOISTURE TRANSPORT. RELATED
ADVECTION NOT AS STRONG IN OUR AREA BUT THIS WILL CHANGE OVER NEXT
FEW DAYS.
DOES NOT APPEAR UPSTREAM CONVECTION WILL MAKE IT INTO REGION THIS
MORNING BUT COULD SEE SOME SEPARATE DEVELOPMENT ON EDGE OF BEST
MOISTURE TRANSPORT TO THE WEST. CLOUD COVER COULD LIMIT HIGH
TEMPERATURES TODAY...LIKE ANY DAY THIS STRETCH...BUT WITH SUCH
DECENT WARM AIR ADVECTION AND TRENDS FROM WEDNESDAY...WILL BUMP UP
HIGHS A CATEGORY OR TWO. MORE LIKELY SCENARIO IS FOR COMPLEX TO
REDEVELOP NORTHWEST OF THE AREA EITHER LATER TODAY OR TONIGHT...
AND THEN DRIFTING INTO AREA FROM THE NORTHWEST WITH SMALL SEVERE
WEATHER THREAT. DAMAGING WIND AND LOCALIZED FLOODING POTENTIAL SEEM
LIKE HIGHEST THREATS IF STORMS ARE STRONG ENOUGH. DEEP LAYER SHEAR
IS NOT OVERLY IMPRESSIVE FOR SUPERCELLS AND RELATED SEVERE WEATHER.
CERTAINLY INSTABILITY WILL NOT BE A PROBLEM AT ALL WITH CLIMBING
MIXED LAYER CAPE VALUES EACH DAY.
ALTHOUGH DETAILS DIFFER...GUIDANCE CONTINUES TREND OF CONTINUED
MOISTURE TRANSPORT FRIDAY AND SATURDAY AS MAIN UPPER AIR DYNAMICS
REMAIN OFF TO THE NORTHWEST. WILL LIKELY SEE DAILY ROUNDS OF
CONVECTION WITH CONTINUED MINOR SEVERE WEATHER THREATS. TIMING HARD
TO PIN POINT THOUGH BUT SOME AREAS COULD SEE SEVERAL INCHES OF RAIN
THROUGH THE WEEKEND. REPEAT ROUNDS DEPENDING ON STORM TRACKS COULD
LEAD TO LATER FLOOD RELATED WATCHES OR WARNINGS GIVEN HIGH
PRECIPITABLE WATER VALUES AND WARM CLOUD DEPTH THAT WILL BE IN PLACE.
.LONG TERM...(SUNDAY THROUGH WEDNESDAY)
ISSUED AT 250 AM CDT THU JUN 20 2013
LATER PERIODS COULD REMAIN ACTIVE FOR THIS AREA OF THE COUNTY AS
UPPER FLOW TRANSITIONS FROM TROUGH OVER WESTERN U.S. TO BUILDING
RIDGE OVER INTERMOUNTAIN WEST.
DEPENDING ON HOW UPPER LOW OVER NORTHWEST TRANSITIONS INTO SOUTHERN
CANADA LATE IN THE WEEKEND MAY DETERMINE HOW MUCH CONVECTION REMAINS
ACROSS WESTERN GREAT LAKES. SUNDAY AND SUNDAY NIGHT COULD BE A
REPEAT PERFORMANCE OF PREVIOUS DAYS WITH MORE STORM COMPLEXES.
FORECAST DETAILS GET EVEN MORE NEBULOUS AFTER THAT AS ANOTHER SHORT
WAVE TROUGH PASSES THROUGH FLOW ACROSS NORTHERN STATES DURING THIS
PATTERN SHIFT. ALTHOUGH BEST ATMOSPHERIC MOISTURE AND CAPE VALUES
COULD BE SHUNTED SOUTH BY THEN...PROXIMITY OF SHORT WAVE TROUGH
COULD GENERATE SMALL WINDOW OF SEVERE WEATHER POTENTIAL BEFORE FLOW
STARTS TO BECOME MORE SHARPLY NORTHWEST AS WESTERN RIDGE BUILDS.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z FRIDAY AFTERNOON)
ISSUED AT 105 PM CDT THU JUN 20 2013
AN AREA OF SHOWERS AND THUNDERSTORMS WILL CONTINUE TO MOVE THROUGH
NORTH CENTRAL WISCONSIN THIS AFTERNOON. ADDITIONAL SCATTERED
SHOWERS AND THUNDERSTORMS WILL POSSIBLE THIS AFTERNOON MAINLY
ALONG AND NORTH OF THE INTERSTATE 90 CORRIDOR. THIS PRECIPITATION
WAS FAR UNCERTAIN TO BE ADDED INTO THE TAFS AT THIS TIME. FOR THIS
EVENING...THE 20.14Z HRRR SUGGESTED THAT A BOW ECHO WOULD AFFECT
THE TAF SITES BETWEEN 21.02Z AND 21.04Z. HOWEVER THE 20.15Z HAS
BACKED AWAY FROM THIS SOLUTION AND NOW HAS AN AREA OF
THUNDERSTORMS MOVING ACROSS EAST-CENTRAL MINNESOTA AND CENTRAL
WISCONSIN. MEANWHILE THE 20.12Z NMM AND ARW ARE IN AGREEMENT THAT
A SQUALL LINE WILL MOVE THROUGH THE TAF SITES BETWEEN 21.07Z AND
21.10Z. SINCE THERE IS ALREADY A LINE DEVELOPING OVER NORTH DAKOTA...
OPTED TO GO MORE WITH THESE SOLUTIONS IN THE TAFS. THERE COULD
POTENTIALLY BE SOME BRIEF WIND GUSTS IN THE 40 TO 50 MPH RANGE.
HOWEVER WITH THERE SOME UNCERTAINTY ON HOW STRONG THE LINE WILL BE
WHEN IT MOVES THROUGH OUR AREA...JUST OPTED TO GO WITH WIND GUSTS
UP TO 30 MPH FOR NOW.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...SHEA
LONG TERM....SHEA
AVIATION...BOYNE
AREA FORECAST DISCUSSION
NWS GREEN BAY WI
1235 PM CDT THU JUN 20 2013
UPDATED AVIATION PORTION FOR 18Z TAF ISSUANCE
.SHORT TERM...TODAY...TONIGHT...AND FRIDAY
ISSUED AT 418 AM CDT THU JUN 20 2013
TIMING OF CONVECTION THE ISSUE THROUGH THIS PERIOD. HAVE FOLLOWED
THE ECMWF WITH AID OF SOME MESO MODELS FOR THIS FORECAST...THOUGH
NOT ANY OF THE MODELS HAVE GOOD HANDLE ON ONGOING CONVECTION OVER
MN/SD AREA.
DISTURBANCES MOVING OUT OF WESTERN TROF TO INTERACT WITH
INCREASINGLY WARM...MOIST AND UNSTABLE AIR TO BRING PERIODS OF
CONVECTION TO THE UPPER MIDWEST AND WESTERN LAKES REGION. TWO
FEATURES KEYING ON THIS MORNING ARE WEAK FRONT EXTENDING SOUTH AND
WEST FROM LOW VCNTY HUDSON BAY INTO LAKE SUPERIOR/NORTHERN MN AREA
AND WARM FRONT EXTENDING EAST OUT OF LOW OVER WESTERN DAKOTAS INTO
SOUTHWEST MN. CONVECTIVE CELLS ALONG FRONT OVER LAKE SUPERIOR
CONTINUE TO HEAD ESE ALONG FRONT WITH LITTLE MOVEMENT TOWARD
NORTHERN WI. LARGER AREA OF CONVECTION JUST NORTH OF WARM FRONT
BEING SUPPORTED BY 40KT LLVL JET. THOUGH WEAKENING...LLVL JET
EXPECTED TO REMAIN FOCUSED TO WEST OF WI TODAY. MESO MODELS/LATEST
HRRR SUGGESTS WEAKENING AS THIS SYSTEM MOVES INTO NORTH CENTRAL WI
THIS AFTERNOON...WHILE WEAKENING CONVECTION ALONG LAKE SUPERIOR
FRONT. MAIN CHANGE WAS TO DECREASE CHANCES SOUTHEAST HALF OF CWA
TODAY.
EC HAS BEEN FAIRLY CONSISTENT PAST FEW RUNS DEVELOPING COMPLEX
OVER SOUTHERN HALF OF MN TONIGHT. COMPLEX TO SHIFT SOUTHEAST
SOUTH OF CWA...ALSO SUGGESTS SECONDARY COMPLEX FORMING FURTHER
NORTH AIDED BY RRQ OF JET OVER SOUTHERN CANADA. THIS COMPLEX TO
SHIFT SOUTHEAST INTO CWA DURING DAY FRIDAY. DO HAVE SOME CONCERNS
REGARDING CONVECTIVE FEEDBACK WITH STRENGTH OF VORT EC HAS MOVING
THROUGH WI DURING DAY FRI. GIVEN THIS SCENARIO...THINKING THAT WITH
MORE CLOUDS AND PCPN EXPECTED FRI WILL LOWER TEMPS SOME...KEEPING
PREVIOUS TEMP FORECAST FOR TODAY. GIVEN MODEST INSTABILITY AM NOT
EXPECTING WIDESPREAD SEVERE THIS PERIOD...THOUGH A FEW STORMS MAY
PRODUCE LARGE HAIL GIVEN LOWER WET BULB ZERO HEIGHTS AND SOME SHEAR.
DUE TO FORECAST UNCERTAINTY FOR BOTH DAYS HAVE STAYED WITH CHANCE
TO LOW LIKELY POPS AT THIS TIME.
.LONG TERM...FRIDAY NIGHT THROUGH WEDNESDAY
ISSUED AT 418 AM CDT THU JUN 20 2013
UPPER RIDGE ACROSS THE EASTERN UNITED STATES THIS WEEKEND WILL
GRADUALLY RETROGRADE INTO THE ROCKIES BY THE MIDDLE OF NEXT WEEK.
POSITION OF 500MB RIDGE WILL PUT US IN THE RING OF FIRE DURING
THE PERIOD...AT LEAST INTO EARLY NEXT WEEK. SOME QUESTIONS LINGER
BY NEXT WEDNESDAY IF FRONTAL BOUNDARY WILL SHIFT SOUTH AS UPPER
TROUGH DEEPENS ACROSS THE WESTERN GREAT LAKES BY THE END OF NEXT
WEEK.
AS ALWAYS THE CASE WITH THESE SCENARIOS...WHEN AND WHERE THUNDERSTORM
COMPLEXES SET UP ALWAYS DIFFICULT TO PINPOINT THIS FAR OUT. TO
COMPLICATE MATTERS...OUTFLOW BOUNDARIES CAN HAVE A BIG IMPACT ON
FRONTAL BOUNDARY POSITION AND FUTURE TRACK OF LATER THUNDERSTORM
COMPLEXES. THE GFS IS SCARY IN THE FACT IT BRINGS A COMPLEX ACROSS
THE WESTERN LAKES ABOUT EVERY 24 HOURS INTO EARLY NEXT WEEK.
ALSO...MAX TEMPERATURES EACH DAY COMPLICATED ON TIMING OF THESE
SYSTEMS IF THEY SHOULD HOLD OFF LATER IN THE DAY OR EVEN INTO THE
EVENING HOURS. WENT CONSERVATIVE ON MAX TEMPERATURES EACH
DAY...BUT LATEST MEX GUIDANCE AND 925/850MB TEMPERATURE STUDY
WOULD INDICATE MAX TEMPERATURES COULD BE EVEN SEVERAL DEGREES
WARMER THAN WHAT IS CURRENTLY IN THE FORECAST. WOULD RATHER RAISE
MAX TEMPERATURE CLOSER TO EACH DAY THAN BACK TRACK DUE TO MORE
CLOUDS OR RAIN.
THE FORECAST FOR FRIDAY NIGHT IS SOMEWHAT MUDDLED TONIGHT DUE TO
THE REMNANTS OF A CONVECTIVE VORT MAX FROM THURSDAY NIGHT COMPLEX
WHICH IS EXPECTED TO MOVE ACROSS THE REGION FRIDAY AFTERNOON.
THERE MAY BE SOME SUBSIDENCE BEHIND THIS SYSTEM EARLY FRIDAY
EVENING...BUT LOW LEVEL SOUTHERLY FLOW AND STEEP MID LEVEL LAPSE
RATES SHOULD BRING A CHANCE OF SHOWERS AND STORMS TO THE REGION
LATER FRIDAY EVENING...ESPECIALLY ACROSS THE SOUTH. THE BETTER
CHANCE FOR SHOWERS AND STORMS WILL BE AFTER MIDNIGHT AS A COMPLEX
OF SHOWERS AND STORMS MOVE INTO THE AREA FROM THE WEST. THIS COMPLEX
IS EXPECTED TO LINGER SATURDAY MORNING ACROSS THE FOX VALLEY AND
LAKESHORE. THERE WILL PROBABLY BE A LULL OR NO ACTIVITY LATE
SATURDAY MORNING INTO THE EARLY AFTERNOON HOURS. ATMOSPHERE SHOULD
BECOME UNSTABLE AGAIN LATER SATURDAY AFTERNOON. MODIFIED SOUNDINGS
INDICATED 2500 TO 3500 J/KG OF CAPE...WINDEX VALUES OF 40 TO 50
KNOTS AND NO CIN. MODELS DO SHOW 500MB SPEED MAX MOVING ACROSS THE
REGION SATURDAY NIGHT TO HELP ENHANCE LIFT. LARGE HAIL IS A LESS OF
A CONCERN AS WET BULB HEIGHTS RISE TO AROUND 13 THOUSAND FEET.
HOWEVER...CAN NOT RULE OUT LARGE HAIL DUE TO MASSIVE AMOUNT OF
CAPE IN THE FORECAST SOUNDINGS. MAX TEMPERATURE DEPENDENT ON
SUNSHINE LATER SATURDAY MORNING AND SATURDAY AFTERNOON...WHICH
SOME SUNSHINE SHOULD BE EXPECTED THIS TIME OF YEAR. ANOTHER
COMPLEX OF THUNDERSTORMS IS EXPECTED SATURDAY NIGHT AND WILL
LINGER SUNDAY MORNING ACROSS THE EAST. WOULD SUSPECT BASED ON THE
MODELS AND MODEL SOUNDINGS...MORE STORMS WILL REFORM SUNDAY
AFTERNOON. WITH THE HEAT AND HUMIDITY AROUND...DAMAGING WINDS AND
LOCALLY HEAVY RAIN ARE THE PRIMARY THREAT WITH THESE STORMS.
BOUNDARY WILL BE LURKING AROUND MONDAY AND TUESDAY...ALONG WITH
THE HEAT AND HUMIDITY. SOME OF THE STORMS COULD BECOME STRONG OR
SEVERE...BUT IT IS TOO EARLY TO DETERMINE IF OR WHEN ORGANIZED
SEVERE WEATHER WOULD OCCUR. SOME INDICATIONS THAT FRONT WILL
BEGIN TO SINK SOUTHWARD TUESDAY NIGHT AS UPPER HEIGHTS BEGIN
TO FALL. WEDNESDAY COULD END UP BEING DRY...HOWEVER DID NOT MAKE
ANY CHANGES TO THAT PERIOD FOR NOW.
SEE HYDROLOGY SECTION FOR MORE DETAILS ON EXPECTED RAINFALL INTO
EARLY NEXT WEEK.
&&
.AVIATION...FOR 18Z TAF ISSUANCE
ISSUED AT 1230 PM CDT THU JUN 20 2013
MAIN FORECAST DIFFICULTY IS TIMING OF PRECIPITATION. SML CLUSTER
OF SHRA AND ISOLD TSRA WL PUSH OUT OF W-C WI AND AFFECT THE
CENTRAL AND N-C WI TAF SITES EARLY THIS AFTN. LOOKS LIKE IT WL
LIFT ARND THE E-C SITES HOWEVER. ALTHOUGH IT/S CERTAINLY POSSIBLE
ADDITIONA SHRA/TSRA WL DEVELOP LATE THIS AFTN AND THIS
EVENING...OPTED INSTEAD TO FOCUS PCPN ON LATE TNGT AND FRI MORNING
WHEN TSTM COMPLEX WL LIKELY BE HEADING ESEWD ACRS THE AREA. THE
LATEST RUC INDICATED LLWS COULD BE A FACTOR OVERNIGHT...BUT IT WAS
AN OUTLIER WITH THE BULK OF THE OTHER GUIDANCE WEAKER WITH THE
WINDS ALOFT. SO LEFT LLWS OUT OF THE TAFS FOR NOW AND WL CONT TO
MONITOR THE SITN.
&&
.MARINE...
ISSUED AT 418 AM CDT THU JUN 20 2013
A INCREASINGLY WARM AND HUMID AIR MASS WILL OVERSPREAD THE COOLER
WATERS OF THE BAY OF GREEN BAY AND LAKE MICHIGAN THURSDAY NIGHT AND
FRIDAY... LEADING TO THE FORMATION OF LOCALLY DENSE MARINE FOG.
THE LOCALLY DENSE MARINE FOG WILL CONTINUE AT TIMES INTO EARLY
NEXT WEEK AS THE WARM AND HUMID AIR MASS REMAINS FIRMLY ENTRENCHED
ACROSS THE REGION. SEVERAL COMPLEXES OF THUNDERSTORMS ARE EXPECTED
FROM TIME TO TIME FRIDAY INTO EARLY NEXT WEEK. THESE STORMS WILL
POSE A SIGNIFICANT RISK FOR MARINERS WITH STRONG WINDS...LOCALLY
HIGHER WAVES...LARGE HAIL AND TORRENTIAL RAINS.
&&
.HYDROLOGY...
ISSUED AT 418 AM CDT THU JUN 20 2013
SEVERAL COMPLEXES OF THUNDERSTORMS ARE EXPECTED FROM FRIDAY INTO
EARLY NEXT WEEK. A VERY WARM AND HUMID AIR MASS WILL BECOME ENTRENCHED
ACROSS THE REGION LATE THIS WEEK AND PERSIST INTO EARLY NEXT WEEK.
PRECIPITABLE WATER VALUES BETWEEN 150 TO 200 PERCENT OF NORMAL ARE
EXPECTED...LEADING TO THE LIKELIHOOD OF TORRENTIAL RAINS AND
POTENTIAL FOR URBAN FLOODING DUE TO THE INTENSE RAINFALL RATES.
ANY TRAINING OR SLOW MOVING THUNDERSTORMS WILL INCREASE THE RISK
OF FLOODING. RAINFALL AMOUNTS OVER THE NEXT 5 DAYS SHOULD RANGE
FROM 1 TO 3 INCHES WITH LOCALLY HIGHER AMOUNTS. WOULD NOT BE
SURPRISED IF THERE WERE A FEW AMOUNTS CLOSE TO 5 INCHES IF STORMS
MOVE OVER THE SAME REGION ON SEVERAL DAYS INTO EARLY NEXT WEEK.
&&
.GRB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM.....TE
LONG TERM......ECKBERG
AVIATION.......SKOWRONSKI
MARINE.........ECKBERG
HYDROLOGY......ECKBERG
AREA FORECAST DISCUSSION
NWS GREEN BAY WI
645 AM CDT THU JUN 20 2013
UPDATED AVIATION PORTION FOR 12Z TAF ISSUANCE
.SHORT TERM...TODAY...TONIGHT...AND FRIDAY
ISSUED AT 418 AM CDT THU JUN 20 2013
TIMING OF CONVECTION THE ISSUE THROUGH THIS PERIOD. HAVE FOLLOWED
THE ECMWF WITH AID OF SOME MESO MODELS FOR THIS FORECAST...THOUGH
NOT ANY OF THE MODELS HAVE GOOD HANDLE ON ONGOING CONVECTION OVER
MN/SD AREA.
DISTURBANCES MOVING OUT OF WESTERN TROF TO INTERACT WITH
INCREASINGLY WARM...MOIST AND UNSTABLE AIR TO BRING PERIODS OF
CONVECTION TO THE UPPER MIDWEST AND WESTERN LAKES REGION. TWO
FEATURES KEYING ON THIS MORNING ARE WEAK FRONT EXTENDING SOUTH AND
WEST FROM LOW VCNTY HUDSON BAY INTO LAKE SUPERIOR/NORTHERN MN AREA
AND WARM FRONT EXTENDING EAST OUT OF LOW OVER WESTERN DAKOTAS INTO SOUTHWEST
MN. CONVECTIVE CELLS ALONG FRONT OVER LAKE SUPERIOR CONTINUE TO
HEAD ESE ALONG FRONT WITH LITTLE MOVEMENT TOWARD NORTHERN WI.
LARGER AREA OF CONVECTION JUST NORTH OF WARM FRONT BEING SUPPORTED
BY 40KT LLVL JET. THOUGH WEAKENING...LLVL JET EXPECTED TO REMAIN
FOCUSED TO WEST OF WI TODAY. MESO MODELS/LATEST HRRR SUGGESTS
WEAKENING AS THIS SYSTEM MOVES INTO NORTH CENTRAL WI THIS
AFTERNOON...WHILE WEAKENING CONVECTION ALONG LAKE SUPERIOR FRONT.
MAIN CHANGE WAS TO DECREASE CHANCES SOUTHEAST HALF OF CWA TODAY.
EC HAS BEEN FAIRLY CONSISTENT PAST FEW RUNS DEVELOPING COMPLEX
OVER SOUTHERN HALF OF MN TONIGHT. COMPLEX TO SHIFT SOUTHEAST
SOUTH OF CWA...ALSO SUGGESTS SECONDARY COMPLEX FORMING FURTHER
NORTH AIDED BY RRQ OF JET OVER SOUTHERN CANADA. THIS COMPLEX TO
SHIFT SOUTHEAST INTO CWA DURING DAY FRIDAY. DO HAVE SOME CONCERNS
REGARDING CONVECTIVE FEEDBACK WITH STRENGTH OF VORT EC HAS MOVING
THROUGH WI DURING DAY FRI. GIVEN THIS SCENARIO...THINKING THAT WITH
MORE CLOUDS AND PCPN EXPECTED FRI WILL LOWER TEMPS SOME...KEEPING
PREVIOUS TEMP FORECAST FOR TODAY. GIVEN MODEST INSTABILITY AM NOT
EXPECTING WIDESPREAD SEVERE THIS PERIOD...THOUGH A FEW STORMS MAY
PRODUCE LARGE HAIL GIVEN LOWER WET BULB ZERO HEIGHTS AND SOME SHEAR.
DUE TO FORECAST UNCERTAINTY FOR BOTH DAYS HAVE STAYED WITH CHANCE
TO LOW LIKELY POPS AT THIS TIME.
.LONG TERM...FRIDAY NIGHT THROUGH WEDNESDAY
ISSUED AT 418 AM CDT THU JUN 20 2013
UPPER RIDGE ACROSS THE EASTERN UNITED STATES THIS WEEKEND WILL
GRADUALLY RETROGRADE INTO THE ROCKIES BY THE MIDDLE OF NEXT WEEK.
POSITION OF 500MB RIDGE WILL PUT US IN THE RING OF FIRE DURING
THE PERIOD...AT LEAST INTO EARLY NEXT WEEK. SOME QUESTIONS LINGER
BY NEXT WEDNESDAY IF FRONTAL BOUNDARY WILL SHIFT SOUTH AS UPPER
TROUGH DEEPENS ACROSS THE WESTERN GREAT LAKES BY THE END OF NEXT
WEEK.
AS ALWAYS THE CASE WITH THESE SCENARIOS...WHEN AND WHERE THUNDERSTORM
COMPLEXES SET UP ALWAYS DIFFICULT TO PINPOINT THIS FAR OUT. TO
COMPLICATE MATTERS...OUTFLOW BOUNDARIES CAN HAVE A BIG IMPACT ON
FRONTAL BOUNDARY POSITION AND FUTURE TRACK OF LATER THUNDERSTORM
COMPLEXES. THE GFS IS SCARY IN THE FACT IT BRINGS A COMPLEX ACROSS
THE WESTERN LAKES ABOUT EVERY 24 HOURS INTO EARLY NEXT WEEK.
ALSO...MAX TEMPERATURES EACH DAY COMPLICATED ON TIMING OF THESE
SYSTEMS IF THEY SHOULD HOLD OFF LATER IN THE DAY OR EVEN INTO THE
EVENING HOURS. WENT CONSERVATIVE ON MAX TEMPERATURES EACH
DAY...BUT LATEST MEX GUIDANCE AND 925/850MB TEMPERATURE STUDY
WOULD INDICATE MAX TEMPERATURES COULD BE EVEN SEVERAL DEGREES
WARMER THAN WHAT IS CURRENTLY IN THE FORECAST. WOULD RATHER RAISE
MAX TEMPERATURE CLOSER TO EACH DAY THAN BACK TRACK DUE TO MORE
CLOUDS OR RAIN.
THE FORECAST FOR FRIDAY NIGHT IS SOMEWHAT MUDDLED TONIGHT DUE TO
THE REMNANTS OF A CONVECTIVE VORT MAX FROM THURSDAY NIGHT COMPLEX
WHICH IS EXPECTED TO MOVE ACROSS THE REGION FRIDAY AFTERNOON.
THERE MAY BE SOME SUBSIDENCE BEHIND THIS SYSTEM EARLY FRIDAY
EVENING...BUT LOW LEVEL SOUTHERLY FLOW AND STEEP MID LEVEL LAPSE
RATES SHOULD BRING A CHANCE OF SHOWERS AND STORMS TO THE REGION
LATER FRIDAY EVENING...ESPECIALLY ACROSS THE SOUTH. THE BETTER
CHANCE FOR SHOWERS AND STORMS WILL BE AFTER MIDNIGHT AS A COMPLEX
OF SHOWERS AND STORMS MOVE INTO THE AREA FROM THE WEST. THIS COMPLEX
IS EXPECTED TO LINGER SATURDAY MORNING ACROSS THE FOX VALLEY AND
LAKESHORE. THERE WILL PROBABLY BE A LULL OR NO ACTIVITY LATE
SATURDAY MORNING INTO THE EARLY AFTERNOON HOURS. ATMOSPHERE SHOULD
BECOME UNSTABLE AGAIN LATER SATURDAY AFTERNOON. MODIFIED SOUNDINGS
INDICATED 2500 TO 3500 J/KG OF CAPE...WINDEX VALUES OF 40 TO 50
KNOTS AND NO CIN. MODELS DO SHOW 500MB SPEED MAX MOVING ACROSS THE
REGION SATURDAY NIGHT TO HELP ENHANCE LIFT. LARGE HAIL IS A LESS OF
A CONCERN AS WET BULB HEIGHTS RISE TO AROUND 13 THOUSAND FEET.
HOWEVER...CAN NOT RULE OUT LARGE HAIL DUE TO MASSIVE AMOUNT OF
CAPE IN THE FORECAST SOUNDINGS. MAX TEMPERATURE DEPENDENT ON
SUNSHINE LATER SATURDAY MORNING AND SATURDAY AFTERNOON...WHICH
SOME SUNSHINE SHOULD BE EXPECTED THIS TIME OF YEAR. ANOTHER
COMPLEX OF THUNDERSTORMS IS EXPECTED SATURDAY NIGHT AND WILL
LINGER SUNDAY MORNING ACROSS THE EAST. WOULD SUSPECT BASED ON THE
MODELS AND MODEL SOUNDINGS...MORE STORMS WILL REFORM SUNDAY
AFTERNOON. WITH THE HEAT AND HUMIDITY AROUND...DAMAGING WINDS AND
LOCALLY HEAVY RAIN ARE THE PRIMARY THREAT WITH THESE STORMS.
BOUNDARY WILL BE LURKING AROUND MONDAY AND TUESDAY...ALONG WITH
THE HEAT AND HUMIDITY. SOME OF THE STORMS COULD BECOME STRONG OR
SEVERE...BUT IT IS TOO EARLY TO DETERMINE IF OR WHEN ORGANIZED
SEVERE WEATHER WOULD OCCUR. SOME INDICATIONS THAT FRONT WILL
BEGIN TO SINK SOUTHWARD TUESDAY NIGHT AS UPPER HEIGHTS BEGIN
TO FALL. WEDNESDAY COULD END UP BEING DRY...HOWEVER DID NOT MAKE
ANY CHANGES TO THAT PERIOD FOR NOW.
SEE HYDROLOGY SECTION FOR MORE DETAILS ON EXPECTED RAINFALL INTO
EARLY NEXT WEEK.
&&
.AVIATION...FOR 12Z TAF ISSUANCE
ISSUED AT 637 AM CDT THU JUN 20 2013
HIGH BASED SHOWERS AND THUNDERSTORMS NOW MOVING INTO NORTH CENTRAL
WI. LITTLE PCPN EXPECTED WITH THESE STORMS. WHEN TO PUT SHOWERS
AND THUNDER IN THE TAFS AND HOW LONG TO KEEP THEM IS THE PROBLEM
THIS AM...WITH CURRENT ACTIVE WEATHER PATTERN. HAVE TRENDED TOWARDS
KEEPING SHOWERS OVER CENTRAL AND NORTH CENTRAL EARLY THIS MORNING
AND AGAIN IN THE AFTERNOON. A THUNDERSTORM COMPLEX IS EXPECTED TO
FORM OVER MN THIS EVENING/TONIGHT AND MOVE THROUGH THE STATE
DURING DAY ON FRI. CONDITIONS SHOULD BE MAINLY VFR OTHER THAN
DURING PRECIPITATION WHEN MVFR VSBYS AND CIGS WILL BE
COMMON...WITH ISOLATED IFR CONDITIONS. CONFIDENCE IN FORECAST
TIMING IS NOT VERY HIGH. &&
.MARINE...
ISSUED AT 418 AM CDT THU JUN 20 2013
A INCREASINGLY WARM AND HUMID AIR MASS WILL OVERSPREAD THE COOLER
WATERS OF THE BAY OF GREEN BAY AND LAKE MICHIGAN THURSDAY NIGHT AND
FRIDAY... LEADING TO THE FORMATION OF LOCALLY DENSE MARINE FOG.
THE LOCALLY DENSE MARINE FOG WILL CONTINUE AT TIMES INTO EARLY
NEXT WEEK AS THE WARM AND HUMID AIR MASS REMAINS FIRMLY ENTRENCHED
ACROSS THE REGION. SEVERAL COMPLEXES OF THUNDERSTORMS ARE EXPECTED
FROM TIME TO TIME FRIDAY INTO EARLY NEXT WEEK. THESE STORMS WILL
POSE A SIGNIFICANT RISK FOR MARINERS WITH STRONG WINDS...LOCALLY
HIGHER WAVES...LARGE HAIL AND TORRENTIAL RAINS.
&&
.HYDROLOGY...
ISSUED AT 418 AM CDT THU JUN 20 2013
SEVERAL COMPLEXES OF THUNDERSTORMS ARE EXPECTED FROM FRIDAY INTO
EARLY NEXT WEEK. A VERY WARM AND HUMID AIR MASS WILL BECOME ENTRENCHED
ACROSS THE REGION LATE THIS WEEK AND PERSIST INTO EARLY NEXT WEEK.
PRECIPITABLE WATER VALUES BETWEEN 150 TO 200 PERCENT OF NORMAL ARE
EXPECTED...LEADING TO THE LIKELIHOOD OF TORRENTIAL RAINS AND
POTENTIAL FOR URBAN FLOODING DUE TO THE INTENSE RAINFALL RATES.
ANY TRAINING OR SLOW MOVING THUNDERSTORMS WILL INCREASE THE RISK
OF FLOODING. RAINFALL AMOUNTS OVER THE NEXT 5 DAYS SHOULD RANGE
FROM 1 TO 3 INCHES WITH LOCALLY HIGHER AMOUNTS. WOULD NOT BE
SURPRISED IF THERE WERE A FEW AMOUNTS CLOSE TO 5 INCHES IF STORMS
MOVE OVER THE SAME REGION ON SEVERAL DAYS INTO EARLY NEXT WEEK.
&&
.GRB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM.....TE
LONG TERM......ECKBERG
AVIATION.......TE
MARINE.........ECKBERG
HYDROLOGY......ECKBERG
FORECAST DISCUSSION FOR ROUTINE MORNING FORECAST ISSUANCE
.SHORT TERM...TODAY...TONIGHT...AND FRIDAY
ISSUED AT 418 AM CDT THU JUN 20 2013
TIMING OF CONVECTION THE ISSUE THROUGH THIS PERIOD. HAVE FOLLOWED
THE ECMWF WITH AID OF SOME MESO MODELS FOR THIS FORECAST...THOUGH
NOT ANY OF THE MODELS HAVE GOOD HANDLE ON ONGOING CONVECTION OVER
MN/SD AREA.
DISTURBANCES MOVING OUT OF WESTERN TROF TO INTERACT WITH
INCREASINGLY WARM...MOIST AND UNSTABLE AIR TO BRING PERIODS OF
CONVECTION TO THE UPPER MIDWEST AND WESTERN LAKES REGION. TWO
FEATURES KEYING ON THIS MORNING ARE WEAK FRONT EXTENDING SOUTH AND
WEST FROM LOW VCNTY HUDSON BAY INTO LAKE SUPERIOR/NORTHERN MN AREA
AND WARM FRONT EXTENDING EAST OUT OF LOW OVER WESTERN DAKOTAS INTO SOUTHWEST
MN. CONVECTIVE CELLS ALONG FRONT OVER LAKE SUPERIOR CONTINUE TO
HEAD ESE ALONG FRONT WITH LITTLE MOVEMENT TOWARD NORTHERN WI.
LARGER AREA OF CONVECTION JUST NORTH OF WARM FRONT BEING SUPPORTED
BY 40KT LLVL JET. THOUGH WEAKENING...LLVL JET EXPECTED TO REMAIN
FOCUSED TO WEST OF WI TODAY. MESO MODELS/LATEST HRRR SUGGESTS
WEAKENING AS THIS SYSTEM MOVES INTO NORTH CENTRAL WI THIS
AFTERNOON...WHILE WEAKENING CONVECTION ALONG LAKE SUPERIOR FRONT.
MAIN CHANGE WAS TO DECREASE CHANCES SOUTHEAST HALF OF CWA TODAY.
EC HAS BEEN FAIRLY CONSISTENT PAST FEW RUNS DEVELOPING COMPLEX
OVER SOUTHERN HALF OF MN TONIGHT. COMPLEX TO SHIFT SOUTHEAST
SOUTH OF CWA...ALSO SUGGESTS SECONDARY COMPLEX FORMING FURTHER
NORTH AIDED BY RRQ OF JET OVER SOUTHERN CANADA. THIS COMPLEX TO
SHIFT SOUTHEAST INTO CWA DURING DAY FRIDAY. DO HAVE SOME CONCERNS
REGARDING CONVECTIVE FEEDBACK WITH STRENGTH OF VORT EC HAS MOVING
THROUGH WI DURING DAY FRI. GIVEN THIS SCENARIO...THINKING THAT WITH
MORE CLOUDS AND PCPN EXPECTED FRI WILL LOWER TEMPS SOME...KEEPING
PREVIOUS TEMP FORECAST FOR TODAY. GIVEN MODEST INSTABILITY AM NOT
EXPECTING WIDESPREAD SEVERE THIS PERIOD...THOUGH A FEW STORMS MAY
PRODUCE LARGE HAIL GIVEN LOWER WET BULB ZERO HEIGHTS AND SOME SHEAR.
DUE TO FORECAST UNCERTAINTY FOR BOTH DAYS HAVE STAYED WITH CHANCE
TO LOW LIKELY POPS AT THIS TIME.
.LONG TERM...FRIDAY NIGHT THROUGH WEDNESDAY
ISSUED AT 418 AM CDT THU JUN 20 2013
UPPER RIDGE ACROSS THE EASTERN UNITED STATES THIS WEEKEND WILL
GRADUALLY RETROGRADE INTO THE ROCKIES BY THE MIDDLE OF NEXT WEEK.
POSITION OF 500MB RIDGE WILL PUT US IN THE RING OF FIRE DURING
THE PERIOD...AT LEAST INTO EARLY NEXT WEEK. SOME QUESTIONS LINGER
BY NEXT WEDNESDAY IF FRONTAL BOUNDARY WILL SHIFT SOUTH AS UPPER
TROUGH DEEPENS ACROSS THE WESTERN GREAT LAKES BY THE END OF NEXT
WEEK.
AS ALWAYS THE CASE WITH THESE SCENARIOS...WHEN AND WHERE THUNDERSTORM
COMPLEXES SET UP ALWAYS DIFFICULT TO PINPOINT THIS FAR OUT. TO
COMPLICATE MATTERS...OUTFLOW BOUNDARIES CAN HAVE A BIG IMPACT ON
FRONTAL BOUNDARY POSITION AND FUTURE TRACK OF LATER THUNDERSTORM
COMPLEXES. THE GFS IS SCARY IN THE FACT IT BRINGS A COMPLEX ACROSS
THE WESTERN LAKES ABOUT EVERY 24 HOURS INTO EARLY NEXT WEEK.
ALSO...MAX TEMPERATURES EACH DAY COMPLICATED ON TIMING OF THESE
SYSTEMS IF THEY SHOULD HOLD OFF LATER IN THE DAY OR EVEN INTO THE
EVENING HOURS. WENT CONSERVATIVE ON MAX TEMPERATURES EACH
DAY...BUT LATEST MEX GUIDANCE AND 925/850MB TEMPERATURE STUDY
WOULD INDICATE MAX TEMPERATURES COULD BE EVEN SEVERAL DEGREES
WARMER THAN WHAT IS CURRENTLY IN THE FORECAST. WOULD RATHER RAISE
MAX TEMPERATURE CLOSER TO EACH DAY THAN BACK TRACK DUE TO MORE
CLOUDS OR RAIN.
THE FORECAST FOR FRIDAY NIGHT IS SOMEWHAT MUDDLED TONIGHT DUE TO
THE REMNANTS OF A CONVECTIVE VORT MAX FROM THURSDAY NIGHT COMPLEX
WHICH IS EXPECTED TO MOVE ACROSS THE REGION FRIDAY AFTERNOON.
THERE MAY BE SOME SUBSIDENCE BEHIND THIS SYSTEM EARLY FRIDAY
EVENING...BUT LOW LEVEL SOUTHERLY FLOW AND STEEP MID LEVEL LAPSE
RATES SHOULD BRING A CHANCE OF SHOWERS AND STORMS TO THE REGION
LATER FRIDAY EVENING...ESPECIALLY ACROSS THE SOUTH. THE BETTER
CHANCE FOR SHOWERS AND STORMS WILL BE AFTER MIDNIGHT AS A COMPLEX
OF SHOWERS AND STORMS MOVE INTO THE AREA FROM THE WEST. THIS COMPLEX
IS EXPECTED TO LINGER SATURDAY MORNING ACROSS THE FOX VALLEY AND
LAKESHORE. THERE WILL PROBABLY BE A LULL OR NO ACTIVITY LATE
SATURDAY MORNING INTO THE EARLY AFTERNOON HOURS. ATMOSPHERE SHOULD
BECOME UNSTABLE AGAIN LATER SATURDAY AFTERNOON. MODIFIED SOUNDINGS
INDICATED 2500 TO 3500 J/KG OF CAPE...WINDEX VALUES OF 40 TO 50
KNOTS AND NO CIN. MODELS DO SHOW 500MB SPEED MAX MOVING ACROSS THE
REGION SATURDAY NIGHT TO HELP ENHANCE LIFT. LARGE HAIL IS A LESS OF
A CONCERN AS WET BULB HEIGHTS RISE TO AROUND 13 THOUSAND FEET.
HOWEVER...CAN NOT RULE OUT LARGE HAIL DUE TO MASSIVE AMOUNT OF
CAPE IN THE FORECAST SOUNDINGS. MAX TEMPERATURE DEPENDENT ON
SUNSHINE LATER SATURDAY MORNING AND SATURDAY AFTERNOON...WHICH
SOME SUNSHINE SHOULD BE EXPECTED THIS TIME OF YEAR. ANOTHER
COMPLEX OF THUNDERSTORMS IS EXPECTED SATURDAY NIGHT AND WILL
LINGER SUNDAY MORNING ACROSS THE EAST. WOULD SUSPECT BASED ON THE
MODELS AND MODEL SOUNDINGS...MORE STORMS WILL REFORM SUNDAY
AFTERNOON. WITH THE HEAT AND HUMIDITY AROUND...DAMAGING WINDS AND
LOCALLY HEAVY RAIN ARE THE PRIMARY THREAT WITH THESE STORMS.
BOUNDARY WILL BE LURKING AROUND MONDAY AND TUESDAY...ALONG WITH
THE HEAT AND HUMIDITY. SOME OF THE STORMS COULD BECOME STRONG OR
SEVERE...BUT IT IS TOO EARLY TO DETERMINE IF OR WHEN ORGANIZED
SEVERE WEATHER WOULD OCCUR. SOME INDICATIONS THAT FRONT WILL
BEGIN TO SINK SOUTHWARD TUESDAY NIGHT AS UPPER HEIGHTS BEGIN
TO FALL. WEDNESDAY COULD END UP BEING DRY...HOWEVER DID NOT MAKE
ANY CHANGES TO THAT PERIOD FOR NOW.
SEE HYDROLOGY SECTION FOR MORE DETAILS ON EXPECTED RAINFALL INTO
EARLY NEXT WEEK.
&&
.AVIATION...FOR 06Z TAF ISSUANCE
ISSUED AT 1236 AM CDT THU JUN 20 2013
A LINE OF SHOWERS AHEAD OF AN APPROACHING COLD FRONT EXTENDED
FROM CENTRAL LAKE SUPERIOR INTO NORTHERN MINNESOTA. ANOTHER AREA
OF SHOWERS AND ISOLATED THUNDER WAS OVER THE DAKOTAS AND WESTERN
MINNESOTA. THIS WAS IN ASSOCIATION WITH AN APPROACHING UPPER LEVEL
SHORT WAVE. WHEN TO PUT SHOWERS AND THUNDER IN THE TAFS AND HOW
LONG TO KEEP THEM THERE WAS PROBLEMATIC. SOME OF THE MODELS WERE
FAIRLY DRY IN FAR EASTERN WISCONSIN...SO HAVE OPTED TO LEAVE OUT
MENTION OF PRECIPITATION AT GRB AND ATW. MODELS SPREAD QPF ACROSS
MOST OF THE AREA DURING THE DAY AS THE FRONT AND SHORT WAVE MOVE
INTO THE STATE. HAVE SHOWERS AND THUNDERSTORMS MAINLY DURING THE
AFTERNOON...FOLLOWED BY A CHANCE FOR SHOWERS AFTER ABOUT 00Z.
CONDITIONS SHOULD BE MAINLY VFR OTHER THAN DURING PRECIPITATION
WHEN MVFR VSBYS AND CIGS WILL BE COMMON...WITH ISOLATED IFR
CONDITIONS. CONFIDENCE IN FORECAST TIMING IS NOT PARTICULARLY HIGH.
&&
.MARINE...
ISSUED AT 418 AM CDT THU JUN 20 2013
A INCREASINGLY WARM AND HUMID AIR MASS WILL OVERSPREAD THE COOLER
WATERS OF THE BAY OF GREEN BAY AND LAKE MICHIGAN THURSDAY NIGHT AND
FRIDAY... LEADING TO THE FORMATION OF LOCALLY DENSE MARINE FOG.
THE LOCALLY DENSE MARINE FOG WILL CONTINUE AT TIMES INTO EARLY
NEXT WEEK AS THE WARM AND HUMID AIR MASS REMAINS FIRMLY ENTRENCHED
ACROSS THE REGION. SEVERAL COMPLEXES OF THUNDERSTORMS ARE EXPECTED
FROM TIME TO TIME FRIDAY INTO EARLY NEXT WEEK. THESE STORMS WILL
POSE A SIGNIFICANT RISK FOR MARINERS WITH STRONG WINDS...LOCALLY
HIGHER WAVES...LARGE HAIL AND TORRENTIAL RAINS. &&
.HYDROLOGY...
ISSUED AT 418 AM CDT THU JUN 20 2013
SEVERAL COMPLEXES OF THUNDERSTORMS ARE EXPECTED FROM FRIDAY INTO
EARLY NEXT WEEK. A VERY WARM AND HUMID AIR MASS WILL BECOME ENTRENCHED
ACROSS THE REGION LATE THIS WEEK AND PERSIST INTO EARLY NEXT WEEK.
PRECIPITABLE WATER VALUES BETWEEN 150 TO 200 PERCENT OF NORMAL ARE
EXPECTED...LEADING TO THE LIKELIHOOD OF TORRENTIAL RAINS AND
POTENTIAL FOR URBAN FLOODING DUE TO THE INTENSE RAINFALL RATES.
ANY TRAINING OR SLOW MOVING THUNDERSTORMS WILL INCREASE THE RISK
OF FLOODING. RAINFALL AMOUNTS OVER THE NEXT 5 DAYS SHOULD RANGE
FROM 1 TO 3 INCHES WITH LOCALLY HIGHER AMOUNTS. WOULD NOT BE
SURPRISED IF THERE WERE A FEW AMOUNTS CLOSE TO 5 INCHES IF STORMS
MOVE OVER THE SAME REGION ON SEVERAL DAYS INTO EARLY NEXT WEEK.
&&
.GRB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM.....TE
LONG TERM......ECKBERG
AVIATION.......MG
MARINE.........ECKBERG
HYDROLOGY......ECKBERG
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
250 AM CDT THU JUN 20 2013
.SHORT TERM...(TODAY THROUGH SATURDAY NIGHT)
ISSUED AT 250 AM CDT THU JUN 20 2013
HEAT...HUMIDITY...AND FUEL FOR THUNDERSTORM COMPLEXES WILL USHER IN
THE OFFICIAL START TO SUMMER DURING THE SHORT TERM. NEARLY
IMPOSSIBLE CHALLENGE WITH CURRENT FORECAST IS TRYING TO TIME AND
PLACE INEVITABLE MESOSCALE CONVECTIVE SYSTEMS INTO THIS WEEKEND.
TIMING OF ANY FEATURE DIFFICULT PAST 24 HOURS AND THIS IS
ILLUSTRATED WELL IN SHORT TERM AND MESOSCALE MODELS THAT SEEM TO
SHIFT SOLUTIONS EVERY RUN.
LARGE UPPER TROUGH OVER NORTHWEST U.S. AND EJECTING SHORT WAVE
ENERGY INTO INTERMOUNTAIN WEST HAS GENERATED ENOUGH RESPONSE IN THE
FORM OF LOW LEVEL JET AND MOISTURE RETURN WHICH WILL SET THE STAGE
FOR ACTIVE SEVERAL DAYS ACROSS THE NORTHERN STATES. ALREADY SEEING
CLUSTERS OF STORMS FROM CENTRAL MINNESOTA BACK INTO NORTH DAKOTA
THIS MORNING IN AREA OF FAVORED MOISTURE TRANSPORT. RELATED
ADVECTION NOT AS STRONG IN OUR AREA BUT THIS WILL CHANGE OVER NEXT
FEW DAYS.
DOES NOT APPEAR UPSTREAM CONVECTION WILL MAKE IT INTO REGION THIS
MORNING BUT COULD SEE SOME SEPARATE DEVELOPMENT ON EDGE OF BEST
MOISTURE TRANSPORT TO THE WEST. CLOUD COVER COULD LIMIT HIGH
TEMPERATURES TODAY...LIKE ANY DAY THIS STRETCH...BUT WITH SUCH
DECENT WARM AIR ADVECTION AND TRENDS FROM WEDNESDAY...WILL BUMP UP
HIGHS A CATEGORY OR TWO. MORE LIKELY SCENARIO IS FOR COMPLEX TO
REDEVELOP NORTHWEST OF THE AREA EITHER LATER TODAY OR TONIGHT...
AND THEN DRIFTING INTO AREA FROM THE NORTHWEST WITH SMALL SEVERE
WEATHER THREAT. DAMAGING WIND AND LOCALIZED FLOODING POTENTIAL SEEM
LIKE HIGHEST THREATS IF STORMS ARE STRONG ENOUGH. DEEP LAYER SHEAR
IS NOT OVERLY IMPRESSIVE FOR SUPERCELLS AND RELATED SEVERE WEATHER.
CERTAINLY INSTABILITY WILL NOT BE A PROBLEM AT ALL WITH CLIMBING
MIXED LAYER CAPE VALUES EACH DAY.
ALTHOUGH DETAILS DIFFER...GUIDANCE CONTINUES TREND OF CONTINUED
MOISTURE TRANSPORT FRIDAY AND SATURDAY AS MAIN UPPER AIR DYNAMICS
REMAIN OFF TO THE NORTHWEST. WILL LIKELY SEE DAILY ROUNDS OF
CONVECTION WITH CONTINUED MINOR SEVERE WEATHER THREATS. TIMING HARD
TO PIN POINT THOUGH BUT SOME AREAS COULD SEE SEVERAL INCHES OF RAIN
THROUGH THE WEEKEND. REPEAT ROUNDS DEPENDING ON STORM TRACKS COULD
LEAD TO LATER FLOOD RELATED WATCHES OR WARNINGS GIVEN HIGH
PRECIPITABLE WATER VALUES AND WARM CLOUD DEPTH THAT WILL BE IN PLACE.
.LONG TERM...(SUNDAY THROUGH WEDNESDAY)
ISSUED AT 250 AM CDT THU JUN 20 2013
LATER PERIODS COULD REMAIN ACTIVE FOR THIS AREA OF THE COUNTY AS
UPPER FLOW TRANSITIONS FROM TROUGH OVER WESTERN U.S. TO BUILDING
RIDGE OVER INTERMOUNTAIN WEST.
DEPENDING ON HOW UPPER LOW OVER NORTHWEST TRANSITIONS INTO SOUTHERN
CANADA LATE IN THE WEEKEND MAY DETERMINE HOW MUCH CONVECTION REMAINS
ACROSS WESTERN GREAT LAKES. SUNDAY AND SUNDAY NIGHT COULD BE A
REPEAT PERFORMANCE OF PREVIOUS DAYS WITH MORE STORM COMPLEXES.
FORECAST DETAILS GET EVEN MORE NEBULOUS AFTER THAT AS ANOTHER SHORT
WAVE TROUGH PASSES THROUGH FLOW ACROSS NORTHERN STATES DURING THIS
PATTERN SHIFT. ALTHOUGH BEST ATMOSPHERIC MOISTURE AND CAPE VALUES
COULD BE SHUNTED SOUTH BY THEN...PROXIMITY OF SHORT WAVE TROUGH
COULD GENERATE SMALL WINDOW OF SEVERE WEATHER POTENTIAL BEFORE FLOW
STARTS TO BECOME MORE SHARPLY NORTHWEST AS WESTERN RIDGE BUILDS.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z THURSDAY NIGHT)
ISSUED AT 1150 PM CDT WED JUN 19 2013
CONVECTION THAT DEVELOPED THIS EVENING OVER SOUTH DAKOTA HAS BEEN
WEAKENING OVER SOUTHWEST MINNESOTA IN FAVOR OF NEW DEVELOPMENT
FARTHER NORTH ACROSS SOUTH DAKOTA INTO NORTH DAKOTA. THIS IS WHERE
THE BEST LOW LEVEL MOISTURE FEED IS OCCURRING AND THE 20.00Z NAM
NOW SHOWS LITTLE TO NO EASTWARD MOVEMENT THROUGH THE NIGHT. THE
20.02Z HRRR SEEMS TO HAVE A DECENT HANDLE ON THE CURRENT ACTIVITY
AND SHOWS A SLOW NORTHEAST MOVEMENT AS IT STAYS IN THE MEAN LOW
LEVEL FLOW. THIS SEEMS REASONABLE BASED ON CURRENT TRENDS AND HAVE
OPTED TO REMOVE THE VCSH FROM BOTH TAF SITES FOR THE LATE NIGHT
INTO THURSDAY MORNING. ALSO PULLED THE VCTS FOR THURSDAY AFTERNOON
AS THE NEW NAM SLOWED THE ARRIVAL OF THE NEXT SHORT WAVE TROUGH
SLIGHTLY TO POINT THAT THERE MAY BE A LITTLE BIT OF SHORT WAVE
RIDGING OCCURRING DURING THE AFTERNOON. STILL WOULD NOT BE TOTALLY
SURPRISED IF SOME STRAY CONVECTION DEVELOPED WITH THE EASTERN
CONVERGENT SIDE OF THE LOW LEVEL MOISTURE TRANSPORT STILL COMING
INTO THE AREA. CONVECTION EXPECTED TO DEVELOP OVER NORTH DAKOTA
AND WESTERN MINNESOTA THURSDAY AFTERNOON AND POSSIBLY MOVE
SOUTHEAST TOWARD THE AREA DURING THE EVENING. THE NAM WOULD
SUGGEST THAT SOME OF THIS ACTIVITY COULD BEGIN TO AFFECT THE TAF
SITES AROUND 21.06Z BUT CONFIDENCE IS NOT HIGH ENOUGH IN THAT
TIMING TO INCLUDE IN THE FORECAST AT THIS TIME.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...SHEA
LONG TERM....SHEA
AVIATION.....04
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
1150 PM CDT WED JUN 19 2013
.SHORT TERM...(TONIGHT THROUGH SATURDAY)
ISSUED AT 303 PM CDT WED JUN 19 2013
MAIN FORECAST CONCERNS ARE PRECIPITATION CHANCES AND POTENTIAL
SEVERE WITH THUNDERSTORMS THROUGH PERIOD.
LATEST WATER VAPOR SATELLITE IMAGERY INDICATES SHORTWAVE RIDGING OVER
EASTERN HALF OF MINNESOTA AND WESTERN WISCONSIN AND UPPER LEVEL
TROUGH DIGGING OVER THE WESTERN UNITED STATES. LATEST 19Z SURFACE
ANALYSIS SHOW SURFACE RIDGE OVER NORTHERN MICHIGAN AND ALLOWING FOR
PARTLY SUNNY SKIES ACROSS MUCH OF THE FORECAST AREA...PER LATEST
VISIBLE SATELLITE IMAGERY.
THE 19.12Z GFS/NAM ARE IN GOOD AGREEMENT DIGGING UPPER LEVEL TROUGH
OVER WESTERN UNITED STATES AND DEVELOPING SOUTHWESTERLY FLOW ALOFT
OVER THE CENTRAL UNITED STATES. BIG CONCERN WILL BE TIMING OF THE
SERIES OF SHORTWAVE TROUGHS EJECTING OUT INTO THE UPPER MIDWEST
TONIGHT INTO SATURDAY. THE 19.12Z GFS/NAM HANDLE THE FIRST COUPLE OF
SHORTWAVES THROUGH 00Z FRIDAY OKAY...THEN AFTER 00Z FRIDAY FLOW
BECOMES MUDDLED WITH MESOSCALE COMPLEX VORTICIES AND CONFIDENCE IN
TIMING OF SHORTWAVE TROUGHS BECOMES VERY LOW.
TONIGHT INTO THURSDAY...FIRST IMPULSE TO PUSH OVER THE AREA
AFTER 06Z THURSDAY. THE 19.12Z GFS/NAM SHOW WEAK MOISTURE TRANSPORT
IN ASSOCIATION WITH THE SHORTWAVE TROUGH AND THE LATEST 19.12Z
ARW/19.17Z HRRR PRODUCE CONVECTION OVER PARTS OF MINNESOTA AFTER 06Z
THURSDAY. THIS CONVECTION MOVES EAST OVER PARTS OF THE FORECAST
AREA. EXPECT SOME SCATTERED SHOWERS AND THUNDERSTORMS ACROSS THE
BY 12Z THURSDAY AND CONTINUE DURING THE DAYTIME HOURS.
THE LATEST 19.12Z GFS/NAM INDICATE SEVERAL IMPULSES TO EJECT OUT
INTO THE UPPER MIDWEST THURSDAY NIGHT INTO SATURDAY AND TO AFFECT
PORTIONS OF THE FORECAST AREA. THE CONCERN WILL BE TIMING AND
PLACEMENT OF EACH INDIVIDUAL IMPULSE INTO THE REGION DURING THIS
TIMEFRAME. THE 19.12Z DETERMINISTIC MODELS SHOW DECENT SURGE OF
MOISTURE TRANSPORT AND LIFT IN ASSOCIATION WITH EACH SHORTWAVE
TROUGHS. CONFIDENCE IS INCREASING THE FORECAST AREA WILL RECEIVE
SHOWERS AND THUNDERSTORMS...HENCE HAVE INCREASED PRECIPITATION
CHANCES ESPECIALLY THURSDAY NIGHT.
THE LATEST 19.12Z GFS/NAM CONTINUE TO SHOW LACK OF DEEP SHEAR WITH
UP TO 30 KNOTS OF 0-6KM WIND SHEAR FROM THURSDAY INTO SATURDAY.
THE DETERMINISTIC MODELS INDICATE AROUND 30 KNOTS OF 0-3KM SHEAR...
WITH INCREASING LOW LEVEL MOISTURE...INSTABILITY WILL INCREASE OVER
THE AREA. THIS WILL ALLOW FOR THE POTENTIAL OF SOME OF THE COMPLEX
OF THUNDERSTORMS TO BECOME SEVERE WITH DAMAGING WINDS THE MAIN
THREAT. PRECIPITABLE WATER VALUES WILL INCREASE TO 1.5 TO 2 INCHES
ACROSS THE FORECAST AREA THURSDAY INTO SATURDAY. IF ANY OF THE
THUNDERSTORMS MOVE OVER THE SAME AREA...FLASH FLOODING WILL BE A
CONCERN.
.LONG TERM...(SATURDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 303 PM CDT WED JUN 19 2013
MAIN FORECAST CONCERNS ARE PRECIPITATION CHANCES AND TEMPERATURES
THROUGH THE PERIOD. THE 19.12Z GFS/ECMWF/GEM ARE IN GOOD AGREEMENT IN
CARVING OUT UPPER LEVEL TROUGH OVER THE WESTERN UNITED STATES AND
CONTINUE SOUTHWESTERLY FLOW ALOFT OVER THE CENTRAL UNITED STATES
THROUGH 00Z TUESDAY. THEN...THE DETERMINISTIC MODELS BEGIN TO BUILD
UPPER LEVEL RIDGE OVER THE WESTERN UNITED STATES FOR TUESDAY AND
WEDNESDAY. BIGGEST DIFFERENCE BETWEEN THE MODELS IS TIMING THE
EMBEDDED SHORTWAVE TROUGHS IN THE SOUTHWESTERLY FLOW ALOFT INTO THE
REGION THROUGH THE PERIOD. THIS WILL HAVE IMPACTS ON THE STRENGTH OF
THE UPPER LEVEL RIDGE...AS THE DETERMINISTIC MODELS SUGGEST RIDGE
FLATTENING OUT OVER THE NORTHERN TIER STATES TUESDAY AND WEDNESDAY.
WITH THE UNCERTAINTY ON TIMING OF SHORTWAVE TROUGHS INTO THE
FORECAST AREA...WILL CONTINUE WITH CHANCES OF PRECIPITATION
THROUGH THE PERIOD. NEXT CONCERN ARE TEMPERATURES THROUGH PERIOD...
THE 19.12Z DETERMINISTIC MODELS SHOW 925MB PLUS 20 TO PLUS 25 DEGREES
CELSIUS OVER FORECAST AREA THROUGH MUCH OF THE PERIOD...WITH THE
WARMEST AIR FILTERING INTO THE FORECAST AREA TUESDAY...WHERE THE
19.12Z ECMWF INDICATES PLUS 26 DEGREES CELSIUS OVER FORECAST AREA AT
00Z WEDNESDAY. THIS WOULD SUGGEST AROUND 90 DEGREE HIGH TEMPERATURES
ACROSS FORECAST AREA TUESDAY.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z THURSDAY NIGHT)
ISSUED AT 1150 PM CDT WED JUN 19 2013
CONVECTION THAT DEVELOPED THIS EVENING OVER SOUTH DAKOTA HAS BEEN
WEAKENING OVER SOUTHWEST MINNESOTA IN FAVOR OF NEW DEVELOPMENT
FARTHER NORTH ACROSS SOUTH DAKOTA INTO NORTH DAKOTA. THIS IS WHERE
THE BEST LOW LEVEL MOISTURE FEED IS OCCURRING AND THE 20.00Z NAM
NOW SHOWS LITTLE TO NO EASTWARD MOVEMENT THROUGH THE NIGHT. THE
20.02Z HRRR SEEMS TO HAVE A DECENT HANDLE ON THE CURRENT ACTIVITY
AND SHOWS A SLOW NORTHEAST MOVEMENT AS IT STAYS IN THE MEAN LOW
LEVEL FLOW. THIS SEEMS REASONABLE BASED ON CURRENT TRENDS AND HAVE
OPTED TO REMOVE THE VCSH FROM BOTH TAF SITES FOR THE LATE NIGHT
INTO THURSDAY MORNING. ALSO PULLED THE VCTS FOR THURSDAY AFTERNOON
AS THE NEW NAM SLOWED THE ARRIVAL OF THE NEXT SHORT WAVE TROUGH
SLIGHTLY TO POINT THAT THERE MAY BE A LITTLE BIT OF SHORT WAVE
RIDGING OCCURRING DURING THE AFTERNOON. STILL WOULD NOT BE TOTALLY
SURPRISED IF SOME STRAY CONVECTION DEVELOPED WITH THE EASTERN
CONVERGENT SIDE OF THE LOW LEVEL MOISTURE TRANSPORT STILL COMING
INTO THE AREA. CONVECTION EXPECTED TO DEVELOP OVER NORTH DAKOTA
AND WESTERN MINNESOTA THURSDAY AFTERNOON AND POSSIBLY MOVE
SOUTHEAST TOWARD THE AREA DURING THE EVENING. THE NAM WOULD
SUGGEST THAT SOME OF THIS ACTIVITY COULD BEGIN TO AFFECT THE TAF
SITES AROUND 21.06Z BUT CONFIDENCE IS NOT HIGH ENOUGH IN THAT
TIMING TO INCLUDE IN THE FORECAST AT THIS TIME.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...DTJ
LONG TERM....DTJ
AVIATION...04
AREA FORECAST DISCUSSION
NWS CHEYENNE WY
530 PM MDT FRI JUN 21 2013
.SHORT TERM...(THIS EVENING THROUGH SUNDAY NIGHT)
ISSUED AT 300 PM MDT FRI JUN 21 2013
BELIEVE WE ARE PRIMED FOR A SEVERE WEATHER EPISODE THIS AFTERNOON.
CONDITIONS ARE SET FOR SEVERE THUNDERSTORMS. CHALLENGES ARE WHERE
AND WHEN.
CURRENTLY...STRATUS LAYER ON VISIBLE IMAGERY CONTINUES TO ERODE
ACROSS DAWES AND SIOUX COUNTIES IN THE PANHANDLE AND NIOBRARA
COUNTY IN EAST CENTRAL WYOMING. DEWPOINTS REMAIN EXTREMELY HIGH
(FOR OUR NECK OF THE WOODS)...IN THE PANHANDLE. ALLIANCE STILL
REPORTING A DEW POINT OF 67 DEGREES...WITH LOW TO MID 60S
ELSEWHERE. LATEST STORM PREDICTION CENTER MESOANALYSIS SHOWING
CAPE ALREADY IN MOST OF THE PANHANDLE OF 4500 TO 5000 J/KG. ALL
THAT IS NEEDED IS A LIFTING MECHANISM AND THAT IS DEVELOPING. A
DRY LINE LAYS ACROSS EXTREME SOUTHEASTERN WYOMING...ROUGHLY FROM
JUST EAST OF CHEYENNE TO JUST WEST OF TORRINGTON AND THEN
NORTHWEST TO DOUGLAS. BEHIND THIS LINE...DEWPOINTS HAVE FALLEN
INTO THE 20S. ALONG THIS LINE...SEEING CU DEVELOPING ALONG THE
LINE. HAVE A PRETTY GOOD CELL ALREADY DEVELOPING IN NORTHERN
LARAMIE COUNTY AND SOUTHERN GOSHEN COUNTY. THIS IS MOST LIKELY THE
START OF OUR EVENT. JUST RECEIVED A SWOMCD FROM SPC AT 113 PM STATING
A WATCH IS LIKELY...SO ANOTHER HOUR OR SO...CONVECTION SHOULD
INITIATE.
LATEST HRRR COMPOSITE REFLECTIVITY FORECAST SHOWING THAT CELL IN
SOUTHERN GOSHEN COUNTY TAKING OFF AROUND 3 PM. BY THAT TIME...LOW
STRATUS SHOULD BE MIXED OUT OVER THE NORTHERN PANHANDLE. SUPER CELL
THEN MOVES EAST INTO THE CENTRAL PANHANDLE. WITH SUCH LARGE
CAPE...GOING TO SEE SOME VERY LARGE HAIL REPORTS. NAM/WRF FORECAST
SOUNDINGS CONTINUE TO SHOW STRONGLY VEERING WINDS WITH
NORTHEASTERLY TO EASTERLY SURFACE WINDS AND 35-40KT SOUTHWESTERLY
WINDS AT 700MBS. MORE THAN ENOUGH SHEAR TO SUPPORT SUPERCELLS
CONTINUING INTO THE PANHANDLE. LATEST NAM HELICITIES FOR LATER
THIS AFTERNOON/EVENING SHOWING 150M2/S2...INCREASING TO OVER
300M2/S2 OVER CONVERSE AND NIOBRARA COUNTIES AFTER 00Z...SPREADING
INTO THE NORTHERN PANHANDLE AFTERWARDS. LCLS QUITE LOW UP THERE AS
WELL...SO THE TORNADO THREAT WILL LIKELY BE FROM 23Z THROUGH MAYBE
02 TO 03Z TIME FRAME. SEVERE THUNDERSTORMS COULD LAST WELL INTO THE
EVENING AND OVERNIGHT HOURS IN THE PANHANDLE.
FOR SATURDAY...PRETTY MUCH A REPEAT OF TODAY WITH SEVERE
THUNDERSTORMS OVER EAST CENTRAL WYOMING AND NEBRASKA PANHANDLE.
SHOULD BEGIN TO SEE A DECREASE IN LOW LEVEL MOISTURE SUNDAY AS
WINDS SHIFT TO THE SOUTHWEST. COULD STILL SEE SOME SEVERE
THUNDERSTORMS IN THE PANHANDLE SUNDAY AFTERNOON.
.LONG TERM...(MONDAY THROUGH FRIDAY)
ISSUED AT 300 PM MDT FRI JUN 21 2013
DUE TO THE THREAT OF SEVERE WEATHER THIS AFTERNOON...WILL KEEP
LONG TERM DISCUSSION BRIEF SINCE NOT MUCH HAS CHANGED SINCE
YESTERDAY.
MODELS CONTINUING TO SHOW SOUTHWEST FLOW ALOFT AND RELATIVELY
QUIET WEATHER FOR NEXT WEEK. THERE APPEARS TO BE LITTLE IN THE WAY OF
RAINFALL CHANCES ACROSS SOUTHEAST WYOMING NEXT WEEK...WITH A
SLIGHTLY BETTER CHANCE ACROSS WESTERN NEBRASKA ON MONDAY AHEAD OF
A WEAK COOL FRONT. MODELS SHOW THIS PACIFIC FRONT SLIDING
EASTWARD ACROSS THE NORTHERN ROCKIES MONDAY NIGHT AND INTO
TUESDAY. THE GFS AND THE GEM HAVE TRENDED TOWARDS THE ECMWF
SOLUTION...SHOWING THE FRONT STALLING FURTHER TO THE NORTH AS THE
UPPER LEVEL TROUGH IS FURTHER NORTH AS WELL AND MORE PROGRESSIVE.
THE MAIN IMPACT FROM THIS FRONT WILL BE WINDY CONDITIONS...MAINLY
WEST OF THE LARAMIE RANGE ON MONDAY AND TUESDAY. TEMPERATURES WILL
NOT LOWER MUCH...IF AT ALL...ESPECIALLY FURTHER SOUTH NEAR THE I80
CORRIDOR. THERE APPEARS TO BE A BETTER CHANCE OF TSTORMS AHEAD OF
THIS FRONT ON MONDAY...AS A WEAK SHORTWAVE MOVES NORTHEAST ACROSS
THE HIGH PLAINS. INCREASED POP MONDAY AND MONDAY EVENING MAINLY
ACROSS WESTERN NEBRASKA. AFTER THAT...MODELS ALL INDICATE A STRONG
UPPER LEVEL HIGH DEVELOPING AND INTENSIFYING NEAR THE FOUR
CORNERS REGION BY WEDNESDAY AND THURSDAY. THIS WILL RESULT IN A
PERIOD OF LIGHT WINDS BUT ALSO VERY WARM OR HOT TEMPERATURES
THROUGH LATE NEXT WEEK. WITH THE EXCEPTION OF MONDAY...KEPT POP
BELOW 10 PERCENT THROUGH THE WEEK. HIGH TEMPERATURES WILL CONTINUE
TO BE ABOVE NORMAL AND GENERALLY IN THE 80S AND 90S. THIS UPPER
LEVEL HIGH WILL BEGIN TO DRIFT WESTWARD BY LATE IN THE
WEEK...ALLOWING A CANADIAN COLD FRONT TO PUSH SOUTH. THIS MAY
INCREASE PRECIPITATION AND TSTORM CHANCES BY NEXT WEEKEND DUE
FAVORABLE EASTERLY FLOW BEHIND THE BOUNDARY.
&&
.AVIATION...(FOR THE 00Z TAF ISSUANCE)
VFR CONDITIONS EXPECTED ALONG AND WEST OF INTERSTATE 25 THROUGH
TONIGHT FOR SOUTHEAST WYOMING...ALTHOUGH SOME LOW CIGS MAY DEVELOP
NEAR THE CHEYENNE RIDGE INCLUDING KCYS AFTER 09Z. STRONG TO SEVERE
THUNDERSTORMS WILL CONTINUE EARLY THIS EVENING ACROSS WESTERN
NEBRASKA AND EXTREME EASTERN WYOMING. ERRATIC GUSTY WINDS UP TO 50
MPH...HAIL...AND IFR CONDITIONS HAVE BEEN REPORTED LATE THIS
AFTERNOON...AND MAY CONTINUE WITH THESE THUNDERSTORMS EAST OF A LINE
FROM KIMBALL NEBRASKA TO LUSK WYOMING. THUNDERSTORMS WILL LINGER
THROUGH LATE TONIGHT BEFORE PUSHING EAST OF THE AREA BY MIDNIGHT.
IFR CONDITIONS IN LOW CIGS AND FOG ARE EXPECTED TO RETURN AFTER
MIDNIGHT ACROSS THE HIGH PLAINS OF WESTERN NEBRASKA AND PORTIONS OF
SOUTHEAST WYOMING.
&&
.FIRE WEATHER...
ISSUED AT 300 PM MDT FRI JUN 21 2013
DRY AND BREEZY CONDITIONS CONTINUE ALONG AND WEST OF THE LARAMIE
RANGE THIS AFTERNOON. TO THE EAST IN THE PANHANDLE AND UP OVER
NIOBRARA COUNTY...HIGH HUMIDITIES WILL LEAD TO SEVERE
THUNDERSTORMS LATER THIS AFTERNOON AND EVENING. HUMIDITIES OUT
WEST ONCE AGAIN IN THE SINGLE DIGITS WITH WIND GUSTS FROM THE
SOUTHWEST AT 30 TO 35 MPH. WINDS WILL EASE AFTER SUNSET.
CONDITIONS LOOK TO REPEAT FOR SATURDAY AND TO A LESSER EXTENT ON
SUNDAY AFTERNOON. STRONG WINDS WILL CONTINUE NEXT
WEEK...PARTICULARLY MONDAY NIGHT INTO TUESDAY WITH WIND GUSTS
EXCEEDING 40 MPH POSSIBLE OUT WEST.
&&
.CYS WATCHES/WARNINGS/ADVISORIES...
WY...NONE.
NE...NONE.
&&
$$
SHORT TERM...CLAYCOMB
LONG TERM...TJT
AVIATION...TJT
FIRE WEATHER...CLAYCOMB
AREA FORECAST DISCUSSION
NWS CHEYENNE WY
1015 PM MDT WED JUN 19 2013
.UPDATE...
ISSUED AT 900 PM MDT WED JUN 19 2013
DESPITE THE VERY HIGH CAPE VALUES (3000-4000 J/KG) ACROSS THE
NEBRASKA PANHANDLE THIS EVENING...STORMS HAVE FAILED TO INITIATE
AND STRENGTHEN. A FEW WEAK SHOWERS/STORMS HAVE OCCURRED OVER THE
SOUTHEAST WYOMING PLAINS AND MOVED INTO THE MORE UNSTABLE AIRMASS
TO THE EAST OF THE DRYLINE...BUT THEN FAILED TO INTENSIFY. IT
APPEARS THAT THE WARM TEMPS ALOFT HAVE BEEN INHIBITING DEEP
CONVECTION. STILL KEPT SLIGHT CHANCE POPS IN FOR THE PANHANDLE AND
NIOBRARA AND CONVERSE COUNTIES THROUGH 06Z. STORMS HAVE BEEN
CONTINUING INTO THE HOURS AFTER SUNSET OVER THE PAST WEEK. THERE
IS CURRENTLY ONE LONE CELL IN COLORADO TO THE SOUTH OF KIMBALL
THAT MAY MOVE INTO THE SOUTHERN PANHANDLE OVER THE NEXT FEW HOURS.
&&
.SHORT TERM...(THIS EVENING THROUGH FRIDAY NIGHT)
ISSUED AT 230 PM MDT WED JUN 19 2013
FORECAST CHALLENGES THROUGH THE SHORT TERM DEAL WITH WINDS THROUGH
FRIDAY.
CURRENTLY...SOUTHWEST WINDS PRETTY STRONG OUT WEST OF THE LARAMIE
RANGE THIS AFTERNOON. GETTING WIND GUSTS OVER 40 MPH IN CARBON
COUNTY...EXTENDING TO THE WEST SLOPES OF THE LARAMIE RANGE. VERY
DRY OUT THAT WAY...RAWLINS REPORTING 6 PERCENT HUMIDITY AT 1 PM
THIS AFTERNOON...LARAMIE 9 PERCENT. LATEST SPC MESOANALYSIS SHOWING
A CAP STILL IN PLACE OUT IN THE PANHANDLE...WITH CONVECTIVE
INHIBITION OF -25 TO -50 J/KG. VISIBLE IMAGERY SHOWING PRETTY MUCH
CLEAR SKIES...WITH NO CU DEVELOPMENT ALL ALONG THE FRONT RANGE.
THERE IS A SMALL WINDOW LATE THIS AFTERNOON WHERE THE SOUTHERN
PANHANDLE SEES A BREAK IN THE CAP. WITH 700MB TEMPERATURES
CLIMBING TO +16C...CONFIDENCE IS NOT HIGH THAT THE CAP WILL BE
BROKEN. LATEST HRRR FORECAST DOES SHOW A FEW CELLS DEVELOPING
ACROSS GOSHEN COUNTY AND THE NORTHERN PANHANDLE AFTER 00Z...SO
WILL KEEP THE SLIGHT CHANCE POPS INHERITED GOING FOR A COUPLE
HOURS THROUGH THE 03Z TIME FRAME.
WINDS EASE THIS EVENING WITH THE GFS 700MB WINDS DECREASING TO
15-20KTS AFTER 06Z. FOR THURSDAY...WINDS TO REMAIN FAIRLY LIGHT
OUT WEST THROUGH THE MORNING AND MID AFTERNOON. THEY DO START
PICKING UP AFTER 00Z...INCREASING TO 25 TO 30KTS BY 06Z. LOOKS
LIKE A PRETTY WINDY DAY ONCE AGAIN OUT WEST OF THE LARAMIE RANGE.
FRIDAY WE START TO SEE A CHANGE AS THE UPPER LOW OVER WESTERN
MONTANA OPENS UP AND A FAIRLY STRONG SHORTWAVE TRACKS INTO WESTERN
WYOMING. 700MB WINDS OUT WEST TO REMAIN 25 TO 35 KTS...BUT WINDS
OVER THE PANHANDLE TURN MORE EASTERLY AS THE LEE SIDE TROUGH
DEEPENS. DEPENDING ON WHICH MODEL YOU LOOK AT...WE COULD SEE
SHOWERS AND THUNDERSTORMS DEVELOPING OUT THAT WAY FRIDAY
AFTERNOON. THE NEW ECMWF PAINTING A WIDESPREAD AREA OF QPF OVER
THE NORTHERN PANHANDLE FRIDAY AFTERNOON AND EVENING. GFS IS DRY
AND LATEST NAM/WRF SIMILAR TO THE ECMWF...THOUGH NOT AS WIDESPREAD
ON PRECIP.
.LONG TERM...(SATURDAY THROUGH WEDNESDAY)
ISSUED AT 345 PM MDT WED JUN 19 2013
PESKY PACIFIC NORTHWEST LOW PRESSURE WILL FINALLY BEGIN TO FILL
THIS WEEKEND AS IT EJECTS INTO THE NRN PLAINS. AN ASSOCIATED
SHORTWAVE WILL TRAVERSE THRU WYOMING ON SATURDAY. MEDIUM RANGE
GUIDANCE VARIES SIGNIFICANTLY ON THE AMOUNT OF AVAILABLE LLVL
MOISTURE ACROSS THE AREA ON SATURDAY. THE GFS IS SIGNIFICANTLY
DRIER FOR MUCH OF THE CWA AS MUCH OF THE MOISTURE IS SHUNTED
MOISTURE ACROSS EASTERN ZONES. MEANWHILE...THE ECMWF IS DEEPER AND
FURTHER WEST WITH THE MOISTURE...WHICH WOULD BACK UP CONVECTION
INTO THE EASTERN SOUTHEAST WYOMING PLAINS. FOR NOW HAVE KEPT
AFTERNOON SHOWER AND THUNDERSTORM CHANCES GOING FOR MUCH OF THE
EASTERN PLAINS. INSTABILITY PARAMETERS WOULD CERTAINLY BE
SUPPORTIVE OF SEVERE WEATHER POTENTIAL IF THE LLVL MOISTURE
MATERIALIZES. THIS WILL BE ESPECIALLY TRUE ACROSS THE WESTERN
NEBRASKA PANHANDLE SATURDAY AFTERNOON AND EARLY EVENING.
LLVL MOISTURE MAY HANG AROUND AGAIN ON SUNDAY AFTERNOON...AS PROGD
INSTABILITIES REMAIN ELEVATED OUT ON THE EASTERN PLAINS. MAIN
QUESTION WILL BE WHETHER OR NOT THERE WILL BE A FOCAL POINT TO
PROVIDE LIFT. HOWEVER...RECENT MODEL GUIDANCE DOES SHOW AT THE
ANOTHER WEAK SHORTWAVE PERHAPS LATE SUNDAY. FOR NOW HAVE ADDED
SHOWER AND THUNDERSTORM CHANCES ALONG AND EAST OF THE LARAMIE
RANGE DURING THE AFTERNOON...SPREADING INTO THE WESTERN NEBRASKA
PANHANDLE BY EARLY EVENING.
FLOW TURNS DRIER AND MORE SOUTHWESTERLY FOR MONDAY THROUGH
WEDNESDAY. SO HAVE THE FIRST HALF OF NEXT WEEK DRY FOR NOW. FIRE
WEATHER CONCERNS WILL BE HEIGHTENED GIVEN THIS TRANSITION TO DRY
CONDITIONS.
PROGD H7 TEMPERATURES WILL HOVER BETWEEN 13-15C THRU MUCH OF THE
PERIOD...WHICH WILL YIELD AFTERNOON HIGHS GENERALLY IN THE 80S
ACROSS SOUTHEAST WYOMING WITH 80S AND LOW/MID 90S ACROSS THE
WESTERN NEBRASKA PANHANDLE.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z THURSDAY EVENING)
ISSUED AT 1005 PM MDT WED JUN 19 2013
VFR PREVAILS. PACIFIC ORIGIN COLD FRONT MOVES THROUGH TONIGHT
WITH WINDS BECOMING WEST AND NORTHWEST. SURFACE LOW PRESSURE
DEVELOPS ON THURSDAY ACROSS EASTERN COLORADO WITH WINDS BECOMING
SOUTH AND SOUTHEAST.
&&
.FIRE WEATHER...
ISSUED AT 230 PM PM MDT WED JUN 19 2013
SOUTHWEST WINDS OF 20 TO 30 MPH SUSTAINED WITH GUSTS TO 40 MPH
WILL CONTINUE THIS AFTERNOON WEST OF THE LARAMIE RANGE. AFTERNOON
HUMIDITIES HAVE ALREADY FALLEN INTO THE SINGLE DIGITS. WINDS ARE
EXPECTED TO EASE BY MID EVENING. POOR HUMIDITY RECOVERIES EXPECTED
OVERNIGHT WEST OF THE LARAMIE RANGE WITH GOOD RECOVERIES IN THE
PANHANDLE. A DRY FORECAST THROUGH SATURDAY WITH WINDS INCREASING
AGAIN FRIDAY AFTERNOON. THIS DUE TO A LOW PRESSURE SYSTEM TRACKING
THROUGH MONTANA. THIS LOW WILL DRAG A COLD FRONT THROUGH THE AREA
SATURDAY WITH SCATTERED CHANCES FOR SHOWERS AND THUNDERSTORMS IN
THE PANHANDLE.
&&
.CYS WATCHES/WARNINGS/ADVISORIES...
WY...NONE.
NE...NONE.
&&
$$
UPDATE...FINCH
SHORT TERM...CLAYCOMB
LONG TERM...HAHN
AVIATION...RUBIN
FIRE WEATHER...CLAYCOMB
AREA FORECAST DISCUSSION
NWS MIAMI FL
256 AM EDT SAT JUN 22 2013
.SHORT TERM (TODAY THROUGH MONDAY)...
DEEP LAYER RIDGE IS BEGINNING TO SHIFT NORTH AND THE 00Z MFL
SOUNDING WAS SHOWING A DEEP EASTERLY FLOW AT 5 TO 10 KNOTS. THE
TROPICAL WAVE THAT WAS PRODUCING NUMEROUS SHOWERS AND SOME
THUNDERSTORMS A FEW DAYS AGO HAS BEEN FIGHTING SOME DRY AIR THAT
SURROUNDS IT AND HAS NOW MOVED INTO THE CENTRAL CARIBBEAN LOSING MOST
OF ITS CONVECTION. THE NORTHERN PORTION OF THE WAVE HAS BECOME A
TROUGH OVER THE CENTRAL BAHAMAS AND HAS SCATTERED SHOWERS AND FEW
THUNDERSTORMS ASSOCIATED WITH IT. THE TROUGH HAS SLOWED ITS
FORWARD MOVEMENT AND MUCH DRIER AIR ALOFT IS AHEAD OF IT ACROSS
THE WESTERN BAHAMAS AND SOUTH FLORIDA. IN FACT, THE SOUNDING LAST
EVENING SHOWED THE PWAT HAD LOWERED TO 1.13 INCHES WHICH IS BELOW
THE 25TH PERCENTILE FOR MID-LATE JUNE AND THERE WERE ONLY A FEW
STORMS LATE YESTERDAY AS A RESULT OF THIS DRY AIR INTRUSION. DUE TO
THE FACT THE ACTUAL WAVE WILL NOW REMAIN WELL TO OUR SOUTH AND THE
TROUGH AXIS HAS SLOWED, THE HRRR IS SHOWING VIRTUALLY NO ACTION
ALONG THE EAST COAST TODAY AND WITH THE DEEP EAST TO WEST STEERING
FLOW DEPICTS SHOWERS AND STORMS DEVELOPING WELL INLAND AFTER 18Z
AND THEN INCREASING AS THEY MOVE TOWARDS THE COLLIER COUNTY COAST
AND THE LAKE REGION. THEREFORE, WILL LOWER THE POPS TO A SILENT 10
PERCENT OVER THE EAST METRO REGION AND TREND UP TO LOW END
SCATTERED FARTHER INLAND. ALL OF THE GLOBAL MODELS ARE IN GOOD
AGREEMENT WITH THIS SCENARIO AND ALSO INCREASE MOISTURE ON SUNDAY
AS THE TROUGH AXIS APPROACHES. THE MOISTURE WILL STILL BE AROUND
ON MONDAY BUT MODEL FORECAST SOUNDINGS ONLY SHOW AN INCREASE IN
PWAT TO NEAR AVERAGE FOR THIS TIME OF YEAR SO SIGNIFICANT RAINFALL
IS NOT ANTICIPATED.
.LONG TERM (MONDAY NIGHT THROUGH FRIDAY)...
THE DEEP LAYER RIDGE WILL BECOME NEARLY STATIONARY ACROSS NORTH
FLORIDA FOR MUCH OF THE UPCOMING WEEK SO THE BEST CHANCES FOR RAIN
WILL BE DURING THE LATE NIGHT AND EARLY MORNING ALONG THE EAST
COAST AND IN THE AFTERNOON TO EARLY EVENING FOR THE INTERIOR AND
SOUTHWEST COAST. MOISTURE INCREASE WILL AGAIN NOT BE PLENTIFUL SO
ONLY ISOLATED AREAS OF HEAVIER RAIN CAN BE EXPECTED MAINLY WHERE
THE AFTERNOON THUNDERSTORMS CAN DEVELOP.
&&
.AVIATION...
QUIET WEATHER IS EXPECTED FOR THE TAF PERIOD WITH VFR CONDITIONS
PREVAILING. THERE IS SOME TROPICAL MOISTURE TRYING TO MAKE ITS WAY
INTO SOUTH FLORIDA, BUT IS HAVING TROUBLE DUE TO THE DRY AIR IN
PLACE IN THE UPPER LEVELS. THERE IS STILL A VERY SLIGHT CHANCE OF
A SHOWER OR A THUNDERSTORM TODAY, BUT TOO UNCERTAIN TO MAKE ANY
REFERENCE IN THE TAFS AT THIS TIME.
&&
.MARINE...
WIND SPEEDS WILL FLUCTUATE THROUGH THE PERIOD BUT REMAIN IN AN
EAST TO SOUTHEAST DIRECTION SO SEAS WILL BE AT 4 FEET OR LESS.
&&
.FIRE WEATHER...
NO PROBLEMS OR CONCERNS WITH AMPLE LOW LEVEL MOISTURE REMAINING IN PLACE.
&&
.PRELIMINARY POINT TEMPS/POPS...
WEST PALM BEACH 89 78 88 78 / 10 20 20 20
FORT LAUDERDALE 88 79 88 80 / 10 20 20 20
MIAMI 89 78 88 79 / 10 20 20 20
NAPLES 92 74 92 75 / 30 20 20 20
&&
.MFL WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
AM...NONE.
GM...NONE.
&&
$$
DISCUSSION/MARINE/FIRE...30/KOB
AVIATION/RADAR...13/SI
AREA FORECAST DISCUSSION
NWS LINCOLN IL
252 AM CDT SAT JUN 22 2013
.DISCUSSION...
ISSUED 250 AM CDT SAT JUN 22 2013
2 AM SATELLITE IMAGERY AND RADAR DATA SHOWING A PAIR OF MCS
SYSTEMS MERGING FROM SOUTH DAKOTA EASTWARD INTO SOUTHERN
WISCONSIN. EASTERN END OF THE LINE OF STORMS HAS MADE A SOUTHWARD
PUSH INTO NORTHEAST ILLINOIS...WITH THIS PART OF THE MCS BECOMING
THE DOMINANT ONE AS LIGHTNING DIMINISHES OVER SOUTHERN MINNESOTA.
LINGERING BOUNDARY FROM THE STORMS IN OUR AREA YESTERDAY WRAPS
AROUND THE SOUTHWEST AND SOUTHEAST PARTS OF THE FORECAST AREA.
STILL SEEING A FEW SPRINKLES IN THE FAR SOUTHEAST CWA WITH THIS
BOUNDARY.
FORECAST CHALLENGES FOR THIS PACKAGE GENERALLY REVOLVE AROUND
TIMING OF THUNDERSTORM CHANCES...AS WELL AS THE ONGOING HEAT AND
HUMIDITY.
SHORT TERM...TODAY THROUGH MONDAY...
MODELS ARE STRUGGLING TO GET A HANDLE ON THE CURRENT SITUATION...
WITH THE HRRR AND THE REGIONAL CANADIAN MODEL CLOSEST TO REALITY.
NEITHER OF THESE MODELS SHOW THE STORMS MAKING IT AS FAR SOUTH AS
OUR FORECAST AREA...BUT AS THE MCS FROM YESTERDAY SHOWED...THAT
OUTCOME IS DEFINITELY NOT GUARANTEED. WILL INCLUDE SOME ISOLATED
THUNDERSTORM MENTION IN THE NORTHEAST THIRD OF THE CWA THIS
MORNING...BETWEEN THIS LINE AND POTENTIALLY SOME DEVELOPMENT ALONG
THE OUTFLOW BOUNDARY...WITH AROUND 30 PERCENT CHANCES ACROSS THE
NORTHEAST DURING THE AFTERNOON. HAVE MENTIONED ISOLATED STORMS
ELSEWHERE THIS AFTERNOON AND EARLY EVENING.
FOCUS CONTINUES TO BE WITH TIMING OF VARIOUS MCS FEATURES THIS
WEEKEND. DEVELOPMENT ACROSS IOWA/MINNESOTA ON SUNDAY EXPECTED TO
EXTEND SOUTHWEST INTO MISSOURI...BUT ONLY THE NAM BRINGS ANY OF IT
THIS FAR EAST BY MONDAY MORNING. HAVE LIMITED ANY 30 PERCENT OR
HIGHER POPS TO THE FAR NORTHWEST LATE SUNDAY NIGHT... WITH MORE
WIDESPREAD CHANCES MONDAY. THE ECMWF AND CANADIAN MODELS SHOW THE
MCS SPREADING OVER THE FORECAST AREA... WHILE THE NAM AND GFS
SHUNT IT MORE TO THE NORTHEAST. SEVERE WEATHER POTENTIAL APPEARS
TO INCREASE BY MONDAY...MAINLY IN THE NORTHWEST CWA.
HAVE KEPT HIGH TEMPERATURES RIGHT AROUND 90 DEGREES FOR THE NEXT
FEW DAYS...WITH HEAT INDEX VALUES IN THE MID TO UPPER 90S. WILL
HAVE TO KEEP AN EYE ON HIGHS FOR MONDAY THOUGH...AS THEY COULD BE
LOWER IF THIS MCS DOES PAN OUT.
LONG TERM...TUESDAY THROUGH FRIDAY...
BROAD EAST-WEST RIDGE EXPECTED TO COVER THE SOUTH HALF OF THE
CONUS MUCH OF THE WEEK...WITH THE MAIN STORM TRACK ACROSS THE
NORTHERN STATES. MCS TRACKS REMAINS THE CONCERN AND ALTHOUGH MANY
OF THEM ARE FURTHER NORTH...LEFTOVER OUTFLOWS MAKE IT DIFFICULT TO
PIN DOWN ANY DRY PERIODS WITH ANY CERTAINTY. HIGHEST POPS FROM
WEDNESDAY NIGHT TO FRIDAY ARE TIED INTO PASSAGE OF A COLD FRONT...
WHICH MAY TAKE UNTIL EARLY FRIDAY TO FULLY PASS THE REGION AS THE
UPPER RIDGING BUILDS ACROSS THE ROCKIES AND PUTS THE MIDWEST MORE
OF A TROUGH. THIS PARTICULAR PATTERN WOULD SHOW THE HEAT FINALLY
BREAKING ON FRIDAY...WITH COOLER CONDITIONS NEXT WEEKEND.
GEELHART
&&
.AVIATION...
ISSUED 1154 PM CDT FRI JUN 21 2013
MAIN ISSUE FOR THE TAFS REMAINS THE NEXT ROUND OF CONVECTION AND
THAT LACK OF CONFIDENCE IN ANY MODEL OUTPUT HELPING WITH THE CALL.
GFS REMAINS STORMY IN THE SHORT TERM...AND DRY TOMORROW AFTERNOON.
WHILE THE NAM/WRF IS MORE FOCUSED ON SHOWERS AND THUNDERSTORMS
FROM MID MORNING ON THROUGH THE AFTERNOON. HAVE TRIED TO SPLIT THE
DIFFERENCE IN THE CURRENT FORECAST WITH A NOD TO PERSISTENCE AND
YESTERDAYS MCS. BEST CHANCES FOR TSRA IN THE AFTERNOON. SOUTHERLY
WINDS DOMINATE...AS WELL AS VFR...THOUGH OBVIOUSLY A DROP IN TS
ACTIVITY. TIMING AND COVERAGE CONFIDENCE LOWER THAN NORMAL.
HJS
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS LINCOLN IL
1158 PM CDT FRI JUN 21 2013
.DISCUSSION...
ISSUED 915 PM CDT FRI JUN 21 2013
WITH THE REMAINS OF THE DYING MCS MOVING OUT OF THE STATE TO THE
EAST/SE...PULLING POPS IN THE OVERNIGHT FOR THE AREA. KEEPING SOME
SLIGHTS IN THE EAST FOR ANY REDEVELOPMENT...BUT THE SYSTEM IS
PULLING TOO FAR TO THE EAST AND THE CURRENT RUC/RAPP RUN IS MOSTLY
DRY IN THE OVERNIGHT. ONLY CONCERN FOR THE OVERNIGHT IS THE
POTENTIAL FOR PATCHY FOG WITH THE MOISTURE IN THE BOUNDARY LAYER
DUE TO THE STORMS. BUT THE DWPTS ARE ACTUALLY LOWER IN THE AREAS
THAT SAW RAIN...AND WELL BELOW THE EXPECTED LOWS. WILL CONTINUE
TO MONITOR...UPDATES OUT MOMENTARILY.
&&
.AVIATION...
ISSUED 1154 PM CDT FRI JUN 21 2013
MAIN ISSUE FOR THE TAFS REMAINS THE NEXT ROUND OF CONVECTION AND
THAT LACK OF CONFIDENCE IN ANY MODEL OUTPUT HELPING WITH THE CALL.
GFS REMAINS STORMY IN THE SHORT TERM...AND DRY TOMORROW AFTERNOON.
WHILE THE NAM/WRF IS MORE FOCUSED ON SHOWERS AND THUNDERSTORMS
FROM MIDMORNING ON THROUGH THE AFTERNOON. HAVE TRIED TO SPLIT THE
DIFFERENCE IN THE CURRENT FORECAST WITH A NOD TO PERSISTENCE AND
YESTERDAYS MCS. BEST CHANCES FOR TSRA IN THE AFTERNOON. SOUTHERLY
WINDS DOMINATE...AS WELL AS VFR...THOUGH OBVIOUSLY A DROP IN TS
ACTIVITY. TIMING AND COVERAGE CONFIDENCE LOWER THAN NORMAL.
HJS
&&
.PREV DISCUSSION...
ISSUED 300 PM CDT FRI JUN 21 2013
INITIAL CONCERNS WILL FOCUS ON THE SEVERE POTENTIAL WITH THE LINE
OF STORMS MOVING ACROSS OUR NORTHERN COUNTIES. THEN ATTENTION
TURNS TO THE HEAT AND HUMIDITY WITH PERIODIC STORM CHANCES IN THIS
SUMMER PATTERN. THE EXTENDED FORECAST STILL CALLS FOR OUR NEXT
COLD FRONT TO ARRIVE AROUND THURSDAY.
SHORT TERM...TONIGHT THROUGH MONDAY.
A 30-40 MPH SOUTHWARD MOVING GUST FRONT IS GENERALLY OUTRUNNING
THE LINE OF STORMS BY 5 TO 10 MILES IN MOST AREAS...EXCEPT FOR IN
THE MID-PORTION OF THE LINE FROM DELAVAN TO BLOOMINGTON. STORM
INITIATION REMAINS CLOSER TO THE GUST FRONT IN THAT AREA. THOSE
STORMS ARE THE STRONGEST AT 230 PM...BUT STILL APPEAR TO BE SUB-
SEVERE. HAIL AND WIND REPORTS HAVE BEEN SPARSE, BUT A FEW TREE LIMBS
MAY HAVE BEEN KNOCKED DOWN NEAR DUNLAP AND THE LARGEST HAIL REPORT
WAS DIME SIZED 1N OF MOSSVILLE EARLIER. STORM INTENSITY HAS
GENERALLY WEAKENED SINCE THOSE REPORTS...SO WE CONTINUE TO MONITOR
FOR ANY INTENSIFICATION. SPC MESO-ANALYSIS PAGE SHOWS MORE STABLE
AIR AHEAD OF THE STORMS...WITH WEAKER 0-6KM BULK SHEAR. THERE IS
STILL 1500 J/KG MUCAPE AVAILABLE...SO THE STORMS MAY LINGER AT
LEAST UNTIL THE INDIANA BORDER EARLY THIS EVENING.
INTO EARLY EVENING...A COUPLE 4KM MODELS ARE SHOWING ADDITIONAL
STORM DEVELOPMENT FARTHER WEST IN EASTERN IOWA/NE MO WHERE
INSTABILITY AND SHEAR PARAMS ARE MORE FAVORABLE FOR STORMS.
HOWEVER...THE 18Z HRRR RUN DOES NOT HAVE ANY INDICATION OF THOSE
STORMS. TAKING EVERYTHING INTO CONSIDERATION...WE TRIED TO MAKE
THE POPS/WEATHER GRIDS CONFORM CLOSELY TO THE NEXT 3-5 HOURS OF
CONVECTION...THEN WENT MORE GENERAL BASED ON SATELLITE, RADAR AND
OBSERVATION TRENDS. WE LINGERED SOME HIGHER POPS THROUGH 03Z THIS
EVENING IN THE EAST TO TREND THE CURRENT STORMS EASTWARD...WITH
SLIGHT CHANCE IN OUR WESTERN COUNTIES TO COVER THE NEXT LINE THAT
MAY ARRIVE.
THE REST OF THE NIGHT SHOULD BE MUGGY AND MILD...AS CLOUDS CLEAR
OUT AND LINGERING NORTH WINDS BEHIND THIS LINE OF STORMS RETURNS
TO SOUTHERLY.
SATURDAY WILL BRING ANOTHER ROUND OF AFTERNOON SHOWERS AND STORMS
AS HIGHS CLIMB INTO THE LOWER 90S AND HEAT INDICES REACH AROUND
100. SEVERE CHANCES SHOULD REMAIN LOW IN OUR COUNTIES...WITH THE
SLIGHT RISK FOR DAY 2 NW OF ILLINOIS. THE TRIGGERS FOR STORMS MAY
BE TIED TO THE RESIDUAL OUTFLOW BOUNDARIES FROM TODAY`S
CONVECTION...AND THE PASSAGE OF A WEAK 500 MB SHORTWAVE.
PRECIPITABLE WATER VALUES AROUND 1.75" WILL ALLOW SOME OF THE
STRONGER STORMS TO BE VERY HEAVY RAIN PRODUCERS...WITH RAINFALL
RATES OF 1-2" PER HOUR. LOCALIZED FLASH FLOODING WILL BE
POSSIBLE...DESPITE THE RELATIVELY DRY CONDITIONS OVER THE PAST
COUPLE OF WEEKS IN MOST AREAS. STORMS SHOULD COME TO AN END BY
SATURDAY EVENING...WITH CLEARING SKIES OVERNIGHT.
SUNDAY WILL SEE LESS FAVORABLE INSTABILITY PARAMS...AS MID LEVEL
WARMING PROVIDES A BETTER CAP ON STORM DEVELOPMENT. WE KEPT A DRY
FORECAST FOR SUNDAY...BUT KEPT THE HEAT AND HUMIDITY HIGH. HEAT
INDEX READING SHOULD REMAIN BELOW SATURDAYS READINGS...BUT STILL
IN THE MID TO UPPER 90S.
MONDAY WILL SEE THE RETURN OF STORM CHANCES AS THE NEXT 500MB
SHORTWAVE CREATES SOME FALLING HEIGHTS AND DESTABILIZES THE LOWER
TROPOSPHERE. STORM DEVELOPMENT SHOULD OCCUR IN THE AFTERNOON...AS
SURFACE HEATING HELPS TO ERODE THE CAP. WE WENT WITH CHANCE POPS
IN THE NW HALF OF OUR FORECAST AREA...WITH SLIGHTS DOWN TO I-70.
LONG TERM...TUESDAY THROUGH FRIDAY.
ANOTHER LULL IN THE STORMS IS EXPECTED MONDAY NIGHT THRU TUESDAY
NIGHT...AS THE UPPER TROUGH IN THE N PLAINS BEGINS TO BECOME
PROGRESSIVE. AS THE UPPER TROUGH REACHES THE GREAT LAKES...A
SURFACE COLD FRONT IS FORECAST TO MOVE ACROSS ILLINOIS ON THURSDAY
OR THURSDAY NIGHT. SHOWERS AND STORMS WILL LIKELY DEVELOP ALONG
THAT FEATURE...DESPITE THE WEAKER APPEARANCE OF THE FRONT IN THE
EXTENDED MODELS.
THE NORTHWEST FLOW BEHIND THAT COLD FRONT WILL HELP DROP HIGHS
FROM THE LOW 90S ON TUESDAY AND WED...BACK INTO THE UPPER 80S
THURSDAY AND LOWER 80S ON FRIDAY. DEWPOINTS WILL DROP INTO THE
LOWER 60S ON FRIDAY AS WELL...PROVIDING SOME RELIEF FROM THE HEAT
AND HUMIDITY.
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS INDIANAPOLIS IN
553 AM EDT SAT JUN 22 2013
.UPDATE...
THE AVIATION SECTION HAS BEEN UPDATED BELOW.
&&
.SYNOPSIS...
ISSUED AT 307 AM EDT SAT JUN 22 2013
POTENTIAL EXISTS FOR OCCASIONAL UPPER DISTURBANCES...RIDING ALONG
THE EDGE OF AN UPPER RIDGE...TO AFFECT CENTRAL INDIANA INTO THE
MIDDLE OF NEXT WEEK. BY NEXT THURSDAY AND FRIDAY...A COLD FRONT MAY
MOVE INTO THE AREA.
&&
.NEAR TERM /TODAY/...
ISSUED AT 307 AM EDT SAT JUN 22 2013
CONFIDENCE IS LOW IN THE THUNDERSTORM FORECAST FOR THIS WEEKEND.
NONE OF THE MODELS APPEAR TO HAVE A HANDLE ON THE MCS CURRENTLY OVER
MN AND WI. THE HRRR MAY BE THE ONLY MODEL TO PROVIDE SOME TRUTH TO
WHAT WILL PREVAIL FOR LATER TODAY...AND THAT IS THE POTENTIAL FOR
REMNANT MCS ACTIVITY TO EVENTUALLY WORK IT/S WAY SOUTH TO CENTRAL
INDIANA BY THIS AFTERNOON AND EARLY EVENING. INCREASED POP COVERAGE
TO INCLUDE THE ENTIRE CWA...WITH SLIGHTLY HIGHER CHANCE POPS ACROSS
THE NORTHERN TIER WHERE ANY REMNANT ACTIVITY IS MOSTLY LIKELY TO
REACH.
IF THIS ACTIVITY DOES REACH CENTRAL INDIANA BY THIS AFTERNOON THEN
TEMPERATURES WILL BE AFFECTED. SINCE CONFIDENCE IS LOW AT THIS
JUNCTURE WILL CONTINUE WITH PERSISTENCE AND WARM HIGHS IN THE UPPER
80S TO AROUND 90.
&&
.SHORT TERM /TONIGHT THROUGH MONDAY NIGHT/...
ISSUED AT 307 AM EDT SAT JUN 22 2013
SLIGHT CHANCE TO LOW CHANCE POPS WILL CONTINUE THIS EVENING AND THEN
BY 06Z BE DRY. LOWS AROUND 70. SUNDAY AND MONDAY WILL BRING WITH IT
SIMILAR CHALLENGES TO THE THUNDERSTORM FORECAST AS A FEW UPPER LEVEL
DISTURBANCES ARE FORECAST TO MOVE THROUGH. INTRODUCED AT LEAST A
SLIGHT CHANCE POP FOR SUNDAY AFTERNOON...AND AGAIN MONDAY AND
MONDAY NIGHT.
THE OTHER STORY THROUGH AT LEAST MID WEEK WILL BE THE SEASONABLY WARM
TEMPERATURES WITH HIGHS REACHING AROUND THE 90 MARK. DID NOT STRAY
FAR FROM MOS.
&&
.LONG TERM /TUESDAY THROUGH SATURDAY/...
ISSUED AT 315 AM EDT SAT JUN 22 2013
A FAIRLY TYPICAL SUMMERTIME PATTERN WILL SET UP DURING THE EARLY TO
MIDDLE PORTION OF THE WORK WEEK WITH ZONAL FLOW TO WEAK RIDGING
ALOFT AND BROAD SOUTH TO SOUTHWEST FLOW NEAR THE SURFACE. CANNOT
RULE OUT ISOLATED AFTERNOON THUNDERSTORMS UNDER THIS REGIME TUESDAY
AND WEDNESDAY...ALTHOUGH CAPPING MAY BE A HINDRANCE...OTHERWISE
EXPECT MAINLY DRY CONDITIONS EARLY WEEK. THINGS DO TRANSITION LATE
WEEK WITH A MORE POTENT UPPER WAVE AND SURFACE SYSTEM MOVING THROUGH
THE AREA WEDNESDAY NIGHT INTO EARLY FRIDAY. HIGHER POPS WILL BE
NECESSARY HERE.
ON TEMPS...ALLBLEND INITIALIZATION WAS REASONABLE...ALTHOUGH DID
BUMP HIGHS UP A DEGREE IN SOME PERIODS TO ACCOUNT FOR POTENTIAL
IMPACT OF OVERDONE PRECIP IN MODELS. MAXES/MINS WILL BE NEAR TO A
BIT ABOVE CLIMO UNTIL VERY LATE IN THE PERIOD POST COLD FRONT...AS
THE ZONAL TO WEAKLY ANTICYCLONIC PATTERN WOULD DICTATE.
&&
.AVIATION /DISCUSSION FOR THE 22/12Z TAFS/...
ISSUED AT 553 AM EDT SAT JUN 22 2013
VFR THROUGH THE PERIOD.
SCT TO BKN MID TO HIGH LEVEL CLOUD ACROSS THE AREA THIS
MORNING...DEBRIS FROM YESTERDAYS STORMS AND FROM UPSTREAM CONVECTION
OVER NORTHERN ILLINOIS. EXPECT DEVELOPMENT OF BKN VFR CUMULUS
TODAY...AND THUNDERSTORMS WILL BE POSSIBLE...BUT TOO LOW PROBABILITY
AND TOO UNCERTAIN TO INCLUDE IN TAF AT THIS TIME. BEST TIME WOULD
ONCE AGAIN BE AFTERNOON INTO EVENING HOURS.
WINDS WILL BE 10KT OR LESS THROUGHOUT THE PERIOD...GENERALLY FROM
180-220 DEGREES.
&&
.IND WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
SYNOPSIS...SMF
NEAR TERM...SMF
SHORT TERM...SMF
LONG TERM....NIELD
AVIATION...NIELD
VISIT US AT HTTP://WWW.WEATHER.GOV/IND
FOLLOW US ON TWITTER AND YOUTUBE AT:
WWW.TWITTER.COM/NWSINDIANAPOLIS
WWW.YOUTUBE.COM/NWSINDIANAPOLIS
AREA FORECAST DISCUSSION
NWS INDIANAPOLIS IN
429 AM EDT SAT JUN 22 2013
.UPDATE...
THE LONG TERM SECTION HAS BEEN UPDATED BELOW.
&&
.SYNOPSIS...
ISSUED AT 307 AM EDT SAT JUN 22 2013
POTENTIAL EXISTS FOR OCCASIONAL UPPER DISTURBANCES...RIDING ALONG
THE EDGE OF AN UPPER RIDGE...TO AFFECT CENTRAL INDIANA INTO THE
MIDDLE OF NEXT WEEK. BY NEXT THURSDAY AND FRIDAY...A COLD FRONT MAY
MOVE INTO THE AREA.
&&
.NEAR TERM /TODAY/...
ISSUED AT 307 AM EDT SAT JUN 22 2013
CONFIDENCE IS LOW IN THE THUNDERSTORM FORECAST FOR THIS WEEKEND.
NONE OF THE MODELS APPEAR TO HAVE A HANDLE ON THE MCS CURRENTLY OVER
MN AND WI. THE HRRR MAY BE THE ONLY MODEL TO PROVIDE SOME TRUTH TO
WHAT WILL PREVAIL FOR LATER TODAY...AND THAT IS THE POTENTIAL FOR
REMNANT MCS ACTIVITY TO EVENTUALLY WORK IT/S WAY SOUTH TO CENTRAL
INDIANA BY THIS AFTERNOON AND EARLY EVENING. INCREASED POP COVERAGE
TO INCLUDE THE ENTIRE CWA...WITH SLIGHTLY HIGHER CHANCE POPS ACROSS
THE NORTHERN TIER WHERE ANY REMNANT ACTIVITY IS MOSTLY LIKELY TO
REACH.
IF THIS ACTIVITY DOES REACH CENTRAL INDIANA BY THIS AFTERNOON THEN
TEMPERATURES WILL BE AFFECTED. SINCE CONFIDENCE IS LOW AT THIS
JUNCTURE WILL CONTINUE WITH PERSISTENCE AND WARM HIGHS IN THE UPPER
80S TO AROUND 90.
&&
.SHORT TERM /TONIGHT THROUGH MONDAY NIGHT/...
ISSUED AT 307 AM EDT SAT JUN 22 2013
SLIGHT CHANCE TO LOW CHANCE POPS WILL CONTINUE THIS EVENING AND THEN
BY 06Z BE DRY. LOWS AROUND 70. SUNDAY AND MONDAY WILL BRING WITH IT
SIMILAR CHALLENGES TO THE THUNDERSTORM FORECAST AS A FEW UPPER LEVEL
DISTURBANCES ARE FORECAST TO MOVE THROUGH. INTRODUCED AT LEAST A
SLIGHT CHANCE POP FOR SUNDAY AFTERNOON...AND AGAIN MONDAY AND
MONDAY NIGHT.
THE OTHER STORY THROUGH AT LEAST MID WEEK WILL BE THE SEASONABLY WARM
TEMPERATURES WITH HIGHS REACHING AROUND THE 90 MARK. DID NOT STRAY
FAR FROM MOS.
&&
.LONG TERM /TUESDAY THROUGH SATURDAY/...
ISSUED AT 315 AM EDT SAT JUN 22 2013
A FAIRLY TYPICAL SUMMERTIME PATTERN WILL SET UP DURING THE EARLY TO
MIDDLE PORTION OF THE WORK WEEK WITH ZONAL FLOW TO WEAK RIDGING
ALOFT AND BROAD SOUTH TO SOUTHWEST FLOW NEAR THE SURFACE. CANNOT
RULE OUT ISOLATED AFTERNOON THUNDERSTORMS UNDER THIS REGIME TUESDAY
AND WEDNESDAY...ALTHOUGH CAPPING MAY BE A HINDRANCE...OTHERWISE
EXPECT MAINLY DRY CONDITIONS EARLY WEEK. THINGS DO TRANSITION LATE
WEEK WITH A MORE POTENT UPPER WAVE AND SURFACE SYSTEM MOVING THROUGH
THE AREA WEDNESDAY NIGHT INTO EARLY FRIDAY. HIGHER POPS WILL BE
NECESSARY HERE.
ON TEMPS...ALLBLEND INITIALIZATION WAS REASONABLE...ALTHOUGH DID
BUMP HIGHS UP A DEGREE IN SOME PERIODS TO ACCOUNT FOR POTENTIAL
IMPACT OF OVERDONE PRECIP IN MODELS. MAXES/MINS WILL BE NEAR TO A
BIT ABOVE CLIMO UNTIL VERY LATE IN THE PERIOD POST COLD FRONT...AS
THE ZONAL TO WEAKLY ANTICYCLONIC PATTERN WOULD DICTATE.
&&
.AVIATION /DISCUSSION FOR THE 22/09Z TAF UPDATE/...
ISSUED AT 429 AM EDT SAT JUN 22 2013
NO SIGNIFICANT CHANGES NECESSARY. PREVIOUS DISCUSSION FOLLOWS.
ISSUED AT 1213 AM EDT SAT JUN 22 2013
EXPECT MOSTLY VFR CONDITIONS EXCEPT PERHAPS SOME BRIEF OVERNIGHT FOG
TONIGHT AT LAF AND MORESO AT HUF WHERE OVER AN INCH OF RAIN FELL
LAST EVENING. HOWEVER...THINK THERE IS A BETTER CHANCE THAT
CONVECTIVE DEBRIS CLOUDS WILL BE SUFFICIENT TO KEEP THE VISIBILITY
P6SM ESPECIALLY AT LAF. COULD SEE A FEW MORE AFTERNOON STORMS MAINLY
AFTER 16Z...BUT CHANCES TOO SMALL TO MENTION. DID GO WITH A BROKEN
VFR CU DECK THOUGH TO STRESS CONVECTIVE POSSIBILITY.
SOUTH AND SOUTHWEST 7 KNOTS OR LESS TONIGHT WILL INCREASE TO AROUND
10 KNOTS FROM THE SOUTHWEST AFTER 16Z SATURDAY AND BECOME LIGHT TO
CALM AFTER 02Z SUNDAY.
&&
.IND WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
SYNOPSIS...SMF
NEAR TERM...SMF
SHORT TERM...SMF
LONG TERM....NIELD
AVIATION...MK/NIELD
VISIT US AT HTTP://WWW.WEATHER.GOV/IND
FOLLOW US ON TWITTER AND YOUTUBE AT:
WWW.TWITTER.COM/NWSINDIANAPOLIS
WWW.YOUTUBE.COM/NWSINDIANAPOLIS
AREA FORECAST DISCUSSION
NWS INDIANAPOLIS IN
315 AM EDT SAT JUN 22 2013
.UPDATE...
THE LONG TERM SECTION HAS BEEN UPDATED BELOW.
&&
.SYNOPSIS...
ISSUED AT 307 AM EDT SAT JUN 22 2013
POTENTIAL EXISTS FOR OCCASIONAL UPPER DISTURBANCES...RIDING ALONG
THE EDGE OF AN UPPER RIDGE...TO AFFECT CENTRAL INDIANA INTO THE
MIDDLE OF NEXT WEEK. BY NEXT THURSDAY AND FRIDAY...A COLD FRONT MAY
MOVE INTO THE AREA.
&&
.NEAR TERM /TODAY/...
ISSUED AT 307 AM EDT SAT JUN 22 2013
CONFIDENCE IS LOW IN THE THUNDERSTORM FORECAST FOR THIS WEEKEND.
NONE OF THE MODELS APPEAR TO HAVE A HANDLE ON THE MCS CURRENTLY OVER
MN AND WI. THE HRRR MAY BE THE ONLY MODEL TO PROVIDE SOME TRUTH TO
WHAT WILL PREVAIL FOR LATER TODAY...AND THAT IS THE POTENTIAL FOR
REMNANT MCS ACTIVITY TO EVENTUALLY WORK IT/S WAY SOUTH TO CENTRAL
INDIANA BY THIS AFTERNOON AND EARLY EVENING. INCREASED POP COVERAGE
TO INCLUDE THE ENTIRE CWA...WITH SLIGHTLY HIGHER CHANCE POPS ACROSS
THE NORTHERN TIER WHERE ANY REMNANT ACTIVITY IS MOSTLY LIKELY TO
REACH.
IF THIS ACTIVITY DOES REACH CENTRAL INDIANA BY THIS AFTERNOON THEN
TEMPERATURES WILL BE AFFECTED. SINCE CONFIDENCE IS LOW AT THIS
JUNCTURE WILL CONTINUE WITH PERSISTENCE AND WARM HIGHS IN THE UPPER
80S TO AROUND 90.
&&
.SHORT TERM /TONIGHT THROUGH MONDAY NIGHT/...
ISSUED AT 307 AM EDT SAT JUN 22 2013
SLIGHT CHANCE TO LOW CHANCE POPS WILL CONTINUE THIS EVENING AND THEN
BY 06Z BE DRY. LOWS AROUND 70. SUNDAY AND MONDAY WILL BRING WITH IT
SIMILAR CHALLENGES TO THE THUNDERSTORM FORECAST AS A FEW UPPER LEVEL
DISTURBANCES ARE FORECAST TO MOVE THROUGH. INTRODUCED AT LEAST A
SLIGHT CHANCE POP FOR SUNDAY AFTERNOON...AND AGAIN MONDAY AND
MONDAY NIGHT.
THE OTHER STORY THROUGH AT LEAST MID WEEK WILL BE THE SEASONABLY WARM
TEMPERATURES WITH HIGHS REACHING AROUND THE 90 MARK. DID NOT STRAY
FAR FROM MOS.
&&
.LONG TERM /TUESDAY THROUGH SATURDAY/...
ISSUED AT 315 AM EDT SAT JUN 22 2013
A FAIRLY TYPICAL SUMMERTIME PATTERN WILL SET UP DURING THE EARLY TO
MIDDLE PORTION OF THE WORK WEEK WITH ZONAL FLOW TO WEAK RIDGING
ALOFT AND BROAD SOUTH TO SOUTHWEST FLOW NEAR THE SURFACE. CANNOT
RULE OUT ISOLATED AFTERNOON THUNDERSTORMS UNDER THIS REGIME TUESDAY
AND WEDNESDAY...ALTHOUGH CAPPING MAY BE A HINDRANCE...OTHERWISE
EXPECT MAINLY DRY CONDITIONS EARLY WEEK. THINGS DO TRANSITION LATE
WEEK WITH A MORE POTENT UPPER WAVE AND SURFACE SYSTEM MOVING THROUGH
THE AREA WEDNESDAY NIGHT INTO EARLY FRIDAY. HIGHER POPS WILL BE
NECESSARY HERE.
ON TEMPS...ALLBLEND INITIALIZATION WAS REASONABLE...ALTHOUGH DID
BUMP HIGHS UP A DEGREE IN SOME PERIODS TO ACCOUNT FOR POTENTIAL
IMPACT OF OVERDONE PRECIP IN MODELS. MAXES/MINS WILL BE NEAR TO A
BIT ABOVE CLIMO UNTIL VERY LATE IN THE PERIOD POST COLD FRONT...AS
THE ZONAL TO WEAKLY ANTICYCLONIC PATTERN WOULD DICTATE.
&&
.AVIATION /DISCUSSION FOR THE 22/06Z TAFS/...
ISSUED AT 1213 AM EDT SAT JUN 22 2013
EXPECT MOSTLY VFR CONDITIONS EXCEPT PERHAPS SOME BRIEF OVERNIGHT FOG
TONIGHT AT LAF AND MORESO AT HUF WHERE OVER AN INCH OF RAIN FELL
LAST EVENING. HOWEVER...THINK THERE IS A BETTER CHANCE THAT
CONVECTIVE DEBRIS CLOUDS WILL BE SUFFICIENT TO KEEP THE VISIBILITY
P6SM ESPECIALLY AT LAF. COULD SEE A FEW MORE AFTERNOON STORMS MAINLY
AFTER 16Z...BUT CHANCES TOO SMALL TO MENTION. DID GO WITH A BROKEN
VFR CU DECK THOUGH TO STRESS CONVECTIVE POSSIBILITY.
SOUTH AND SOUTHWEST 7 KNOTS OR LESS TONIGHT WILL INCREASE TO AROUND
10 KNOTS FROM THE SOUTHWEST AFTER 16Z SATURDAY AND BECOME LIGHT TO
CALM AFTER 02Z SUNDAY.
&&
.IND WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
SYNOPSIS...SMF
NEAR TERM...SMF
SHORT TERM...SMF
LONG TERM....NIELD
AVIATION...MK
VISIT US AT HTTP://WWW.WEATHER.GOV/IND
FOLLOW US ON TWITTER AND YOUTUBE AT:
WWW.TWITTER.COM/NWSINDIANAPOLIS
WWW.YOUTUBE.COM/NWSINDIANAPOLIS
AREA FORECAST DISCUSSION
NWS INDIANAPOLIS IN
310 AM EDT SAT JUN 22 2013
.UPDATE...
THE SYNOPSIS...NEAR TERM AND SHORT TERM SECTIONS HAVE BEEN UPDATED
BELOW.
&&
.SYNOPSIS...
ISSUED AT 307 AM EDT SAT JUN 22 2013
POTENTIAL EXISTS FOR OCCASIONAL UPPER DISTURBANCES...RIDING ALONG
THE EDGE OF AN UPPER RIDGE...TO AFFECT CENTRAL INDIANA INTO THE
MIDDLE OF NEXT WEEK. BY NEXT THURSDAY AND FRIDAY...A COLD FRONT MAY
MOVE INTO THE AREA.
&&
.NEAR TERM /TODAY/...
ISSUED AT 307 AM EDT SAT JUN 22 2013
CONFIDENCE IS LOW IN THE THUNDERSTORM FORECAST FOR THIS WEEKEND.
NONE OF THE MODELS APPEAR TO HAVE A HANDLE ON THE MCS CURRENTLY OVER
MN AND WI. THE HRRR MAY BE THE ONLY MODEL TO PROVIDE SOME TRUTH TO
WHAT WILL PREVAIL FOR LATER TODAY...AND THAT IS THE POTENTIAL FOR
REMNANT MCS ACTIVITY TO EVENTUALLY WORK IT/S WAY SOUTH TO CENTRAL
INDIANA BY THIS AFTERNOON AND EARLY EVENING. INCREASED POP COVERAGE
TO INCLUDE THE ENTIRE CWA...WITH SLIGHTLY HIGHER CHANCE POPS ACROSS
THE NORTHERN TIER WHERE ANY REMNANT ACTIVITY IS MOSTLY LIKELY TO
REACH.
IF THIS ACTIVITY DOES REACH CENTRAL INDIANA BY THIS AFTERNOON THEN
TEMPERATURES WILL BE AFFECTED. SINCE CONFIDENCE IS LOW AT THIS
JUNCTURE WILL CONTINUE WITH PERSISTENCE AND WARM HIGHS IN THE UPPER
80S TO AROUND 90.
&&
.SHORT TERM /TONIGHT THROUGH MONDAY NIGHT/...
ISSUED AT 307 AM EDT SAT JUN 22 2013
SLIGHT CHANCE TO LOW CHANCE POPS WILL CONTINUE THIS EVENING AND THEN
BY 06Z BE DRY. LOWS AROUND 70. SUNDAY AND MONDAY WILL BRING WITH IT
SIMILAR CHALLENGES TO THE THUNDERSTORM FORECAST AS A FEW UPPER LEVEL
DISTURBANCES ARE FORECAST TO MOVE THROUGH. INTRODUCED AT LEAST A
SLIGHT CHANCE POP FOR SUNDAY AFTERNOON...AND AGAIN MONDAY AND
MONDAY NIGHT.
THE OTHER STORY THROUGH AT LEAST MID WEEK WILL BE THE SEASONABLY WARM
TEMPERATURES WITH HIGHS REACHING AROUND THE 90 MARK. DID NOT STRAY
FAR FROM MOS.
&&
.LONG TERM /MONDAY NIGHT THROUGH FRIDAY/...
ISSUED AT 242 PM EDT FRI JUN 21 2013
SUMMER TIME PATTERN WILL BE IN PLACE FOR THE BEGINNING OF LONG TERM
PERIOD. WEAK RIDGING ALOFT AND SOUTH/SOUTHWEST FLOW AT THE SURFACE
WILL BE CONDUCIVE TO PERIODS OF DIURNALLY DRIVEN SHOWERS AND
THUNDERSTORMS. HOWEVER...CHANCES FOR SHOWERS AND THUNDERSTORMS
WILL INCREASE LATER IN THE WEEK /MAINLY THURSDAY/ AS AN UPPER LEVEL
LOW TRAVERSES ONTARIO...AND ITS TRAILING COLD FRONT SWEEPS ACROSS
CENTRAL INDIANA.
TEMPS...FELT THAT LATEST INITIALIZATION WAS ON THE COOL SIDE FOR
WARM SOUTHWEST FLOW AT THE SURFACE ON TUESDAY AND WEDNESDAY. AS A
RESULT...TRENDED 1 TO 3 DEGREES ABOVE GUIDANCE FOR DAYTIME HIGHS ON
THOSE DAYS. OTHERWISE...WAS ABLE TO STICK CLOSE TO ALLBLEND
INITIALIZATION NUMBERS FOR THE REMAINDER OF THE EXTENDED PERIOD.
&&
.AVIATION /DISCUSSION FOR THE 22/06Z TAFS/...
ISSUED AT 1213 AM EDT SAT JUN 22 2013
EXPECT MOSTLY VFR CONDITIONS EXCEPT PERHAPS SOME BRIEF OVERNIGHT FOG
TONIGHT AT LAF AND MORESO AT HUF WHERE OVER AN INCH OF RAIN FELL
LAST EVENING. HOWEVER...THINK THERE IS A BETTER CHANCE THAT
CONVECTIVE DEBRIS CLOUDS WILL BE SUFFICIENT TO KEEP THE VISIBILITY
P6SM ESPECIALLY AT LAF. COULD SEE A FEW MORE AFTERNOON STORMS MAINLY
AFTER 16Z...BUT CHANCES TOO SMALL TO MENTION. DID GO WITH A BROKEN
VFR CU DECK THOUGH TO STRESS CONVECTIVE POSSIBILITY.
SOUTH AND SOUTHWEST 7 KNOTS OR LESS TONIGHT WILL INCREASE TO AROUND
10 KNOTS FROM THE SOUTHWEST AFTER 16Z SATURDAY AND BECOME LIGHT TO
CALM AFTER 02Z SUNDAY.
&&
.IND WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...SMF
NEAR TERM...SMF
SHORT TERM...SMF
LONG TERM....TDUD
AVIATION...MK
VISIT US AT HTTP://WWW.WEATHER.GOV/IND
FOLLOW US ON TWITTER AND YOUTUBE AT:
WWW.TWITTER.COM/NWSINDIANAPOLIS
WWW.YOUTUBE.COM/NWSINDIANAPOLIS
AREA FORECAST DISCUSSION
NWS TOPEKA KS
355 AM CDT SAT JUN 22 2013
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 343 AM CDT SAT JUN 22 2013
LARGE COMPLEX OF RAIN AND THUNDERSTORMS CONTINUES TO MARCH EASTWARD
ACROSS MUCH OF NORTH AND EAST NEBRASKA AND POINTS NE. SOUTHERN
PROGRESS OF THE OUTFLOW HAS SLOWED SOMEWHAT THE PAST HOUR OR SO.
SHORTWAVE TROF NOTED IN WV IMAGERY OVER EASTERN KS ATTM...BUT IS
PRODUCING ONLY CLOUDS SO FAR AS IT PASSES. EVENING SOUNDING AT TOP
SHOWED STEEP LAPSE RATES IN THE 750 TO 550 MB LAYER...HOWEVER CAP IS
STRONG BELOW 700MB AND COLUMN IS DRY THROUGH ABOUT 400MB. ONLY
GUIDANCE THAT SUGGESTS PRECIP THIS MORNING HAS BEEN OUT WEST WITH
THE HRRR FOR SEVERAL RUNS...ALL OTHERS REMAIN DRY. WILL CARRY A
SILENT POP WEST OF MANHATTAN FOR A FEW HOURS THIS MORNING. COULD
GET A BRIEF BREAK NORTH FROM SOME OF THE OUTFLOW FROM THE
NORTH...BUT EXPECT THAT WOULD BE SHORT LIVED. HIGHS STILL EXPECTED
INTO THE LOWER TO MIDDLE 90S WITH HEAT INDICES RUNNING AROUND 100
ALONG THE KS RIVER VALLEY. WINDS BECOME QUITE BREEZY OUT OF THE
SOUTH AS YOU GO WESTWARD...WITH SUSTAINED AFTERNOON WINDS AROUND 30
WITH GUSTS 35-40 POSSIBLE. WILL MONITOR TRENDS FOR WIND ADVISORY
BUT IS BORDERLINE AT THIS TIME. OVERNIGHT LOWS EXPECTED ON THE WARM
SIDE AGAIN IN THE MIDDLE 70S. 67
.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 343 AM CDT SAT JUN 22 2013
MID RANGE AND EXTENDED FORECAST (SUNDAY THROUGH FRIDAY)...
VERY LITTLE CHANGE IN THIS FORECAST PACKAGE AS MODELS ARE STILL
CONSISTENT IN SHOWING A LARGE SCALE RIDGING PATTERN ACROSS THE
SOUTHEASTERN PORTION OF THE CONUS THROUGH THE WEEKEND...WITH A
PACIFIC TROUGH OVER THE WEST COAST. LIGHT SOUTHWEST FLOW WILL BE
PRESENT OVER THE ROCKY MOUNTAINS UP THROUGH THE NORTHERN
PLAINS...WITH THE CENTRAL PLAINS BEING ON THE EASTERN FRINGE OF THE
BETTER FLOW. EXPECT WARM TEMPERATURES TO CONTINUE FOR SUNDAY...WITH
A PRETTY DECENT CHANCE FOR RAIN SUNDAY NIGHT AS A DISTURBANCE WITHIN
THE SOUTHWESTERLY FLOW ALOFT WILL TRIGGER A ROUND OF THUNDERSTORMS
ACROSS SOUTHERN NEBRASKA AND NORTHERN KANSAS. THE BEST CHANCE FOR
RAIN WILL BE ALONG THE KS/NE BORDER...WITH DECREASING CHANCES
FURTHER SOUTH ALONG INTERSTATE 70.
EXPECT LITTLE IN THE WAY OF CONVECTIVE CHANCES AFTER THE SUNDAY
NIGHT ROUND OF THUNDERSTORMS. ECMWF HAS BEEN CONSISTENT IN
PREDICTING THE FOUR CORNERS MID LEVEL RIDGE TO SET UP BY MID
WEEK...WHICH WILL KEEP TEMPERATURES IN THE AREA WARM THROUGH THE
EXTENDED PERIOD. TEMPERATURES GENERALLY WILL REMAIN IN THE LOWER TO
MID 90S ACROSS EASTERN KANSAS THROUGH THE EXTENDED PERIOD...WITH
TEMPS REACHING THE MID TO UPPER 90S IN WESTERN KANSAS. THE NEXT
CHANCES FOR RAIN WILL BE RATHER MINIMAL AS A BOUNDARY LOOKS TO SLIDE
INTO THE AREA IN THE THURSDAY/FRIDAY TIME FRAME. THIS BOUNDARY WOULD
BE THE FOCUS FOR ANY POTENTIAL CONVECTION DURING THAT TIME PERIOD.
MADE VIRTUALLY NO CHANGE TO THE FORECAST FOR THE LATE PART OF THE
WEEK FOR THESE POTENTIAL SHOWERS.
JL
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT)
ISSUED AT 1128 PM CDT FRI JUN 21 2013
VFR CONDITIONS AS SCT TO BKN CIRRUS CLOUDS SKIRT ACROSS
KTOP/KFOE/KMHK. EXPECT GRADIENT TO RELAX SLIGHTLY WITH OVERNIGHT
SOUTH WINDS AROUND 10 KTS AT KTOP/KFOE. KMHK SHOULD STAY UP NEAR 12
KTS. WIND DIRECTION BACKS SLIGHTLY TO THE SOUTH AT SITES...INCREASING
BETWEEN 15-20 KTS WITH GUSTS 25-30 KTS AFT 14Z.
&&
.TOP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...CRAVEN
LONG TERM...LEIGHTON
AVIATION...BOWEN
AREA FORECAST DISCUSSION
NWS GOODLAND KS
1154 PM MDT FRI JUN 21 2013
.SHORT TERM...(THIS EVENING THROUGH SATURDAY)
ISSUED AT 216 PM MDT FRI JUN 21 2013
AS OF 3 PM CDT...2 PM MDT...SKIES ACROSS THE TRI-STATE WERE CLEAR
ALBEIT A LITTLE HAZY FROM SMOKE THAT CONTINUES TO STREAM IN FROM
FIRES IN SOUTH CENTRAL COLORADO. SOME CUMULUS AND TOWERING CUMULUS
COULD BE SEEN ON VISIBLE SATELLITE IMAGERY JUST NORTH OF
AKRON...COLORADO. SOUTH WINDS HAVE PICKED UP MAINLY EAST OF A LINE
FROM TRENTON...NEBRASKA TO COLBY AND LEOTI KANSAS AS A SURFACE LOW
PRESSURE SYSTEM DEEPENS TO THE WEST. TEMPERATURES RANGED FROM THE LOW
90S IN EAST COLORADO TO NEAR 100 ACROSS SOME PARTS OF KANSAS AND
SOUTHWEST NEBRASKA. VERY DRY AIR WAS ALSO STARTING TO MOVE IN FROM
THE SOUTHWEST.
SIMILAR TO YESTERDAY...ISOLATED THUNDERSTORMS ARE EXPECTED TO
DEVELOP ALONG A DRYLINE. SURFACE CONVERGENCE IS BEGINNING TO APPEAR
IN THE SURFACE WIND FIELD ALONG THE DRYLINE WHICH WILL BE THE FOCUS
OF STORM DEVELOPMENT. THE HRRR AND NAM MODELS SUGGEST STORM
INITIATION WILL OCCUR IN FAR WESTERN KANSAS. STORMS SHOULD BE
CONFINED MAINLY ALONG AND EAST OF A LINE FROM YUMA COLORADO TO
GOODLAND KANSAS TO TRIBUNE KANSAS AND WEST OF A LINE FROM MCCOOK
NEBRASKA TO RUSSELL SPRINGS KANSAS. ANY STORM THAT IS ABLE TO
DEVELOP WILL BE STRONG TO SEVERE WITH LARGE HAIL AND DAMAGING WINDS
AS THE MAIN THREATS.
FOR TONIGHT...GUSTY WINDS WILL CONTINUE A LOW LEVEL JET DEVELOPS
OVER THE EASTERN HALF. WINDS SHOULD BE BELOW WIND ADVISORY CRITERIA
WITH THE STRONGEST WINDS REMAINING TO THE SOUTH OVER SOUTHWEST AND
SOUTH CENTRAL KANSAS. LOWS WILL STRUGGLE TO FALL TONIGHT WITH THE
ATMOSPHERE IN A MIXED STATE SO HAVE GONE ABOVE GUIDANCE FOR LOWS.
TONIGHTS TEMPERATURE FORECAST IS VERY SIMILAR TO WHAT ACTUALLY
OCCURRED LAST NIGHT.
FOR TOMORROW...A REPEAT OF TODAY IS EXPECTED FOR THE MOST PART.
TEMPERATURES ARE NOT EXPECTED TO BE AS HOT AS TODAY WITH HIGHS ONLY
REACHING THE MID TO UPPER 90S WITH A FEW SPOTS REACHING 100. A WEAK
FRONT WILL MOVE INTO THE AREA FROM THE NORTH...RESULTING IN MAINLY A
WIND SHIFT WITH EVER SO SLIGHTLY COOLER TEMPERATURES. WITH A DRYLINE
STILL IN PLACE...ISOLATED THUNDERSTORMS ARE POSSIBLE AGAIN FOR
TOMORROW. ANY STORMS THAT ARE ABLE TO DEVELOP WOULD LIKELY BECOME
SEVERE. THERE IS A SLIGHT RISK FOR SEVERE WEATHER ACROSS SOUTHWEST
NEBRASKA TOMORROW AND THAT SEEMS REASONABLE GIVEN THE LOCATION OF
THE FRONT TOMORROW. THE FRONT SHOULD PROVIDE A BETTER FOCUS FOR
THUNDERSTORM DEVELOPMENT OVER THE NORTHERN THIRD OF THE FORECAST
AREA. GUSTY SOUTH WINDS ARE EXPECTED AGAIN WITH A LOW PRESSURE
DEEPENING TO THE WEST.
.LONG TERM...(SATURDAY NIGHT THROUGH FRIDAY)
ISSUED AT 215 PM MDT FRI JUN 21 2013
A SIGNIFICANT CHANGE IN THE UPPER PATTERN WILL TAKE PLACE DURING
THIS EXTENDED PERIOD. THE CURRENT SOUTHWEST FLOW ALOFT
ACCOMPANIED BY NUMEROUS MINOR DISTURBANCES WILL TRANSITION TO A
BUILDING UPPER RIDGE...STARTING OVER NM/AZ TUESDAY AND ULTIMATELY
ENCOMPASSING ALL OF THE CENTRAL ROCKIES BY THE END OF THE WEEK.
THERE STILL LOOKS TO BE A COUPLE OF OPPORTUNITIES FOR STORMS
COMING OUT OF COLORADO AND MOVING ACROSS THE CWA SATURDAY AND
SUNDAY EVENING AS WEAK SHORT WAVE TROUGHS MOVE THROUGH THE FLOW.
AFTER THAT...PRECIP POTENTIAL WILL DIMINISH AS THE UPPER RIDGE AND
WARMING MID-LEVEL TEMPS BEGIN TO DOMINATE.
TEMPERATURES ARE EXPECTED TO REMAIN WELL ABOVE NORMAL DURING THE
PERIOD WITH HIGHS MOSTLY IN THE MIDDLE 90S TO NEAR 100 AND LOWS IN
THE 60S TO NEAR 70.
CURRENT EXTENDED GUIDANCE BEYOND THIS PERIOD SUGGESTS THE UPPER
RIDGE WILL CONTINUE TO BUILD NORTH TOWARD IDAHO BY NEXT WEEKEND.
IF THAT PANS OUT...THE UPPER FLOW WILL BECOME NORTHWEST OVER THE
CWA POSSIBLY INCREASING THE CHANCE FOR LATE DAY STORMS MOVING
SOUTHEAST OFF THE CHEYENNE RIDGE.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT)
ISSUED AT 1148 PM MDT FRI JUN 21 2013
CONDITIONS AT MCK AND GLD WILL CONTINUE TO BE VFR THROUGH THE TAF
PERIOD. OUTFLOW FROM THUNDERSTORMS OVER CENTRAL SOUTHERN NEBRASKA
REINFORCING THE COLDFRONTAL BOUNDARY WILL CONTINUE TO AFFECT THE
WINDS AT MCK...KEEPING THEM GENERALLY LIGHT OUT OF THE NORTHEAST
TO EAST OVERNIGHT. WINDS AT MCK WILL TURN SOUTH AND BECOME GUSTY
DURING THE AFTERNOON AS THE FRONT MOVES NORTHWARD. GUSTY SOUTH WINDS
AT GLD WILL SLACKEN SOMEWHAT TOWARDS SUNRISE...BUT WILL RETURN BY
AFTERNOON. THERE IS A POSSIBILITY OF ISOLATED THUNDERSTORMS
DEVELOPING ACROSS THE CENTRAL HIGH PLAINS REGION DURING THE
AFTERNOON AND EVENING...BUT THE CHANCE OF ANY STORM MOVING OVER
EITHER TAF SITE IS SLIM ENOUGH THAT ANY MENTION OF STORMS HAS BEEN
LEFT OUT.
&&
.FIRE WEATHER...
ISSUED AT 216 PM MDT FRI JUN 21 2013
CRITICAL FIRE WEATHER CONDITIONS ARE DEVELOPING TO THE
SOUTHWEST...MAINLY OVER GREELEY AND WALLACE COUNTIES KANSAS AND
CHEYENNE AND KIT CARSON COUNTIES IN COLORADO. EVEN THOUGH RED FLAG
CRITERIA WILL BE MET FOR THESE LOCATIONS TODAY FOR WIND AND RELATIVE
HUMIDITY...RECENT RAINFALL AND HIGHER FUEL MOISTURE CONTENT ARE
PREVENTING EXPLOSIVE FIRE WEATHER CONDITIONS FROM BECOMING A
PROBLEM. THEREFORE...HAVE OPTED NOT TO ISSUE A RED FLAG WARNING.
THE SAME STORY WILL REPEAT ITSELF AGAIN TOMORROW WITH LOW RELATIVE
HUMIDITIES FILTERING IN FROM THE SOUTHWEST AND WINDS INCREASING
BEHIND THE DRYLINE IN THE AFTERNOON. FUELS COULD BE MORE RIPE FOR
FIRE POTENTIAL TOMORROW AFTER A COUPLE HOT DAYS WITH LITTLE RAINFALL
BUT THINKING THAT FUEL MOISTURE WILL STILL BE HIGH ENOUGH THAT A RED
FLAG WARNING WILL NOT BE WARRANTED.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
SHORT TERM...RRH
LONG TERM...DLF
AVIATION...LOCKHART
FIRE WEATHER...RRH
AREA FORECAST DISCUSSION
NWS JACKSON KY
120 AM EDT SAT JUN 22 2013
.UPDATE...
ISSUED AT 120 AM EDT SAT JUN 22 2013
CLUSTER OF SHOWERS/STORMS WHICH DROPPED SOME SMALL HAIL IN THE TRI-
CITIES AREA OF NORTHEAST TENNESSEE EARLIER CONTINUES TO PINWHEEL
WESTWARD. THESE SHOWERS/STORMS APPEAR DESTINED TO VISIT HARLAN AND
BELL COUNTIES IN SOME SHAPE OR FORM AND WILL HOLD ONTO A 20 POP
THROUGH THE REST OF THE NIGHT FOR THOSE AREAS. OTHERWISE...SHOWERS IN
THE BLUEGRASS HAVE DIED OUT SO REMOVED ANY MENTION OF RAIN THERE.
REST OF THE FORECAST IS ON TRACK...
UPDATE ISSUED AT 900 PM EDT FRI JUN 21 2013
THUNDERSTORMS HAVE DIED DOWN IN OUR FORECAST AREA...BUT ISOLATED
STORMS CONTINUE TO FIRE AROUND US. INHERITED FORECAST DROPPED ALL
MENTION OF POPS AFTER 00Z EXCEPT DOWN SOUTH ALONG THE TN AND VA
BORDERS AND KEPT WITH THIS THINKING. WILL NEED TO MONITOR THE STORMS
FIRING OVER THE BLUEGRASS THOUGH TO MAKE SURE ADDITIONAL ACTIVITY
DOESN/T FIRE ON OUTFLOWS INTO OUR BLUEGRASS COUNTIES. OTHERWISE...
SHOULD BE A QUIET NIGHT WITH REPEAT VALLEY FOG DEVELOPMENT. FORECAST
LOWS IN THE LOW TO MID 60S LOOK GOOD.
&&
.SHORT TERM...(THIS EVENING THROUGH SATURDAY NIGHT)
ISSUED AT 314 PM EDT FRI JUN 21 2013
BEEN WATCHING THE MCS ENTERING NORTHERN ILL TO SEE HOW FAR SOUTH IT
WILL KEEP GOING AND WHERE THE OUTFLOW BOUNDARIES END UP. CURRENT
THINKING IS THAT IF IT DOES NOT FALL APART BEFORE IT REACHES THE
AREA...IT SHOULD STAY WEST OF THE AREA. THE HRRR IS SHOWING ISOLATED
TO SCATTERED SHOWERS AND THUNDERSTORMS DEVELOPING DURING THE
AFTERNOON AND EVENING HOURS. THE INSTABILITY IS THERE TO SUPPORT
THUNDERSTORM DEVELOPMENT. ONE CONCERN IS THE DRY AIR IN THE MID
LAYERS WHICH COULD HELP TO PRODUCE SOME STRONG OUTFLOW WINDS. THE
OTHER CONCERN IS THAT THE WINDS ALOFT ARE SO LIGHT...THE STORMS WILL
BE MOVING VERY SLOWLY. THIS MAY ALLOW A LOT OF PRECIPITATION TO FALL
OVER A SMALL AREA AND COULD RESULT IN DITCHES AND LOW WATER
CROSSINGS TO RUN FULL. THERE HAS ALREADY BEEN ONE STRONG STORM
DEVELOP OVER LESLIE COUNTY THIS AFTERNOON. NO REPORTS OF ANY DAMAGE
OR FLOODING WERE RECEIVED. A REPEAT OF THIS DIURNALLY BASED PULSE
THUNDERSTORM ACTIVITY IS ANTICIPATED ON SATURDAY.
.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 314 PM EDT FRI JUN 21 2013
FAIRLY BUSY PATTERN FOR THE OFFICIAL START OF SUMMER. OVERALL
MODELS ARE IN GOOD AGREEMENT THROUGH THE EXTENDED. IN FAIRLY HIGH
AMPLITUDE FLOW...CORE WESTERLIES REMAINS NORTH OF OUR AREA UNTIL THE
END OF THE FORECAST WINDOW. EASTERN CONUS RIDGING ALOFT RETREATS
WESTWARD WITH TIME THROUGH THE PERIOD. EMBEDDED WITHIN THIS RIDGE
EARLY ON IS AN AREA OF TROUGH-I-NE SS OR A CENTER OF RELATIVE LOWER
HEIGHTS. THIS LOCALIZED AREA OF LOWER HEIGHTS WILL OPEN UP AND DRIFT
NORTHEAST THROUGH THE LATTER PART OF THE WEEKEND AND EARLY NEXT
WEEK...SPREADING ITS LIMITED INFLUENCE THROUGH THE SOUTHERN
APPALACHIANS. FOR SUCH A WEAK FEATURE...CONSISTENT WITH THIS TIME OF
YEAR...THE MODELS DO RATHER WELL IN DEPICTING SIMILAR EVOLUTIONS...
THOUGH THE ECMWF MAINTAINS THE DISTINCT UPPER LOW LONGER THAN THE
GFS. THIS RIDGING ACROSS THE REGION IS SUPPRESSED SOUTHWARD AS THIS
AREA OF LOWER HEIGHTS GRADUALLY LIFTS NORTHWARD ACROSS EASTERN
KENTUCKY SUNDAY. THEREAFTER THE RIDGE SHIFTS WESTWARD AND THE
PATTERN AMPLIFIES...RESULTING IN ENERGY ALONG THE NORTHERN TIER
SETTLING SOUTHWARD ALONG THE EASTERN SIDE OF THE RIDGE...EFFECTIVELY
CARVING OUT A TROUGH OVER THE EASTERN CONUS TO FINISH OUT THE WEEK.
SENSIBLE WEATHER WILL BE DOMINATED BY THE DIURNAL CYCLE THROUGH THE
BULK OF THE EXTENDED AS SFC HIGH PRESSURE OVER THE AREA WILL BE TOO
WEAK TO SUPPRESS ALL CONVECTION ONCE DAYTIME HEATING KICKS IN. THERE
IS REALLY NO FEATURE TO KEY IN ON FOR MORE ORGANIZED...WIDESPREAD
ACTIVITY THROUGH THE START OF THE UPCOMING WORK WEEK. THAT CHANGES
TOWARDS WEEKS END AS A STORM SYSTEM DROPPING SOUTHWARD OUT OF CANADA
HELPS TO GENERATE A BETTER CHANCE FOR RAIN ACROSS OUR AREA...THOUGH
TIMING AND SPECIFICS REMAIN IN DOUBT. WARM AND SEASONABLE WEATHER IS
THUS ON TAP FOR THE REST OF THE WEEKEND AND THROUGH THE START OF THE
NEW WORK WEEK. DURING THE FIRST FEW DAYS OF THE EXTENDED...OUR BEST
OPPORTUNITY FOR SOME GARDEN VARIETY...HIT AND MISS THUNDERSTORMS
APPEARS TO BE SUNDAY AS HEIGHTS DROP SLIGHTLY DUE TO THE PASSING
FEATURE...DISTURBANCE FROM THE SOUTH. ADDITIONAL CLOUD COVER...AND A
BETTER POTENTIAL OF CONVECTION AFTER MID WEEK ON SHOULD HELP TEMPER
THE WARMTH A BIT.
FOR TEMPS GENERALLY STAYED CLOSE TO A BLEND OF MODEL GUIDANCE WHILE
MAINTAINING EFFECTS OF RELATIVE ELEVATION AL DIFFERENCES...WHERE
APPLICABLE.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT)
ISSUED AT 120 AM EDT SAT JUN 22 2013
SURFACE HIGH PRESSURE WILL PROVIDE FOR MAINLY VFR CONDITIONS AND
LIGHT WINDS ACROSS THE AREA THROUGH THE PERIOD. PATCHY VALLEY FOG
WILL CONTINUE TO DEVELOP THROUGH DAWN...WITH SOME VSBY REDUCTIONS
EXPECTED AT LOZ AND SME. ISOLATED THUNDERSTORMS WILL THEN REFIRE
AFTER ABOUT 17Z TOMORROW...ALTHOUGH THE PROBABILITY THAT ONE WILL
IMPACT A TAF SITE IS ONLY AROUND 20 PERCENT.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...ABE
SHORT TERM...JJ
LONG TERM...GREIF/RAY
AVIATION...ABE
AREA FORECAST DISCUSSION
NWS WAKEFIELD VA
402 AM EDT SAT JUN 22 2013
.SYNOPSIS...
A WEAK AREA OF LOW PRESSURE WILL LINGER ALONG THE NORTH CAROLINA
COAST THROUGH TODAY. HIGH PRESSURE WILL BE ANCHORED OFF THE MID
ATLANTIC COAST SUNDAY THROUGH THE MIDDLE OF NEXT WEEK.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
INTERESTING FORECAST CHALLENGES TODAY. HAVE CONVECTION DEVELOPING
ALONG A COASTAL FRONT OVER NORTH CAROLINA AND SLOWLY MOVING NORTH.
THIS IS ASSOCIATED WITH A WEAK PV MAX ALOFT AND CAN BE SEEN ON
WATER VAPOR. MEANWHILE HAVE A WEAK RIDGE OF HIGH PRESSURE ALOFT
JUST TO THE NORTH OF THIS FEATURE. THIS HIGH IS SLOWLY WEAKENING
AND MOVING TO THE EAST. THIS WILL ALLOW THE WEAK TROF TO LIFT
NORTH TODAY. CAN SEE WINDS BECOMING MORE SOUTHEAST ALOFT ON VWP
OBSERVATIONS AROUND THE AREA. THIS WILL ADVECT PLENTY OF MOISTURE
INTO THE SOUTHERN PART OF THE CWA TODAY. WILL FOLLOW THE HRRR IDEA
OF MOVING THE PRECIPITATION FROM NORTH CAROLINA INTO SOUTHEAST
VIRGINIA DURING THE MORNING. COULD SEE SOME BRIEF HEAVY RAIN WITH
SOME OF THE SHOWERS. BY THIS AFTERNOON THE MOISTURE WILL BE PULLED
NORTH OVER MOST OF THE CWA. HOWEVER THE UPPER TROF WILL BE
WEAKENING AND THIS WILL CAUSE THE PRECIPITATION TO MORE SCATTERED.
THIS FOLLOWS THE NAM AND GFS. ALSO THE SREF SHOWS THE BEST CHANCES
FOR PRECIP MOVING TO THE WESTERN SECTIONS OF THE CWA DURING THE
AFTERNOON AND EVENING. SINCE WESTERN AREAS WILL BE SLOWER TO CLOUD
UP WILL HAVE SOME MORE CAPE TO AIDE IN THUNDERSTORM DEVELOPMENT.
AGAIN WITH PLENTY OF MOISTURE AROUND COULD SEE SOME BRIEF HEAVY
DOWNPOURS. TEMPERATURES WILL BE DEPENDENT ON THE AMOUNT OF CLOUD
COVER TODAY. EXPECT TO KEEP MAXES AROUND 80 SOUTHEAST BUT REACH
THE MID 80S ACROSS WESTERN SECTIONS. AGAIN THIS IS CLOSE TO MOS GUIDE.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH MONDAY/...
A SECOND UPPER LOW OVER GEORGIA TODAY WILL SLOWLY LIFT NORTH LATE
TONIGHT AND MOVE ACROSS TO THE WEST OF THE AREA ON SUNDAY. THE
UPPER LOW AGAIN WILL BE WEAKENING AS IT MERGES WITH THE WESTERLY
TO THE NORTH. THIS THIS WILL HELP TO KEEP BEST CHANCES OF SHOWERS
AND THUNDERSTORMS IN THE WESTERN AREAS TONIGHT AND SATURDAY. WITH
THE HIGH PRESSURE CENTERED OFF THE MID ATLANTIC COAST WILL HAVE
MOISTURE FEED OFF THE WATER COMING INTO THE AREA WITH SOME RISE TO
THE EAST WINDS AS THEY APPROACH THE RIDGES TO THE WEST. BY MONDAY
THIS FEATURE IS WEAKENING AND MORE NORTHEAST AWAY FROM THE AREA.
HOWEVER WILL STILL HAVE PLENTY OF MOISTURE ACROSS THE AREA SO WILL
CONTINUE CHANCE TO SLIGHT CHANCE POPS ESPECIALLY ON MONDAY
AFTERNOON WITH THE BEST CHANCES IN THE WEST WHERE THE LOW LEVEL
EAST WINDS WILL BEGIN TO RISE AS THEY APPROACH THE MOUNTAINS TO
THE WEST. WILL GO FAIRLY CLOSE TO MOS GUIDANCE FOR TEMPERATURES
WITH THE WARMEST DAY ON MONDAY AS LESS CLOUD COVER THEN. LOWS AT
NIGHT WILL MAINLY BE IN THE MID TO UPPER 60S.
&&
.LONG TERM /MONDAY NIGHT THROUGH FRIDAY/...
PERIOD BEGINS WITH A BROAD MID/UPPER LEVEL RIDGE CENTERED OVER
MUCH THE SOUTHERN TIER OF THE CONUS...GRADUALLY EVOLVING INTO A
STRONG RIDGE OVER THE SW STATES WITH A FAIRLY DEEP TROUGH CENTERED
JUST NORTH OF THE GREAT LAKES ACRS ONTARIO CANADA. THIS WILL
TRANSLATE INTO A W/NW UPPER FLOW PATTERN INTO THE MID ATLC STATES.
WHILE A SERIES OF WEAK SHORTWAVES BEGIN TO SHUNT THE RIDGE OFF TO
THE S/SW OF THE CWA TUE/WED...TIMING THESE FEATURES IN THE MEDIUM
RANGE IS QUITE DIFFICULT SO WILL GENLY HAVE ONLY A 20% CHANCE FOR
MAINLY DIURNAL/AFTN/EVENING TSTMS TUE/WED. TEMPERATURES WILL WARM
TO A LITTLE ABOVE AVG FOR LATE JUNE...MAINLY IN THE UPPER 80S TO
LOWER 90S FOR HIGHS WITH LOWS IN THE UPPER 60S TO LOWER 70S. BY
THU/FRI...A MORE DEFINED SFC BOUNDARY SETS UP NOT TOO FAR TO THE
NORTH OF THE CWA...AND 500 MB HEIGHTS SLOWLY FALL...SO HAVE POPS
HIGHER THAN CLIMO BOTH DAYS (ESPECIALLY FRI). HIGHS IN THE UPPER
80S TO LOWER 90S AND LOWS MAINLY FROM 70-75.
&&
.AVIATION /08Z SATURDAY THROUGH WEDNESDAY/...
MODELS CONT TO SHOW A PERSISTENT NE FLOW AHEAD OF APPROACHING SYSTEM
FROM THE SOUTH. ANOTHER STRATUS LAYER DEVELOPING IN ASSOCIATION WITH
REMNANT LLVL MOISTURE TRAPPED BELOW NOCTURNAL INVERSION. THIS WL
LIKELY BRING ANOTHER NIGHT OF IFR VSBYS W/PATCHY FOG. AS LLVL
MOISTURE CONTINUES TO INCREASE, EXPECT IFR TO BE A BIT MORE
WIDESPREAD THIS MORNING THAN THE PREVIOUS TWO.
ASIDE FROM THE FOG, EXPECT SHRAS TO PUSH NW FROM COASTAL CAROLINAS
TOWARDS COASTAL TERMINALS, AND HV LEANED ON HRRR IN TAKING THE
PARENT LOW AND THE ASSOCIATED PCPN SHIELD N-NW INTO NE NC AFTER 12Z
THIS MORNING. PREDOMINATE -RA/SHRA NOW IN THE TAF AT PHF/ECG/ORF
AFTER 13Z, EVENTUALLY REACHING RIC AFTER 15Z. DO EXPECT TO SEE SOME
BREAKS IN STRATUS AT RIC/SBY AFTER 13-15Z, BUT HV GONE WITH VICINITY
SHRA WORDING FOR SCT SHRAS THAT ARE EXPECTED TO DEVELOP BY ERY SAT
AFTN IVOF RIC AS LOW PRESSURE SLOWLY WEAKENS TO OUR SOUTH. CIGS WL
GENERALLY RANGE FROM MVFR TO VFR THROUGH THE AFTN
OUTLOOK: MORE LATE NIGHT STRATUS IS EXPECTED LATE TONIGHT/SUN
MORNING. OTHERWISE, EXPECT PREDOMINATE VFR CONDITIONS ASIDE FROM
SCATTERED MAINLY DIURNALLY DRIVEN SHRAS SUN AND THROUGH MIDWEEK
AS BREEZY S-SW FLOW REDEVELOPS MON-TUE.
&&
.MARINE...
LATEST OBS CONTINUE TO INDICATE ONSHORE (EAST) FLOW ACRS THE ENTIRE
REGION. WINDS ARE GENLY 15 KT OR LESS (LIGHTEST OVER NORTHERN
AREAS). SEAS CONTINUE TO SLOWLY SUBSIDE THIS MORNING, NOW AOB 4FT
ACROSS THE MID-ATLANTIC WATERS.
NO MAJOR CHANGES TO THE GOING FORECAST WITH THIS PACKAGE. MSAS 3-HR
PRESSURE FALLS CONTINUES TO SHOW SLOW WEAKENING/SLACKENING OF THE
PRESSURE GRADIENT BETWEEN THE INVERTED SFC TROUGH/LOW NEAR KILM AT
08Z AND HIGH PRESSURE OFF NORTHERN MID-ATLANTIC COAST. ACCORDINGLY,
CONTINUE TO EXPECT CONDITIONS TO REMAIN SUB-SCA TODAY. STILL RATHER
UNFAVORABLE BOATING CONDITIONS TODAY, WITH PREDOMINATE LLVL FLOW OUT
OF THE E/NE FLOW AGAIN TODAY WITH SEAS 4 FT AND WAVES 2-3 FT AT THE
MOUTH OF THE BAY.
AS COASTAL FRONT PUSHES BACK WEST THIS AFTN/EVENING, EXPECT WINDS TO
GRADUALLY VEER AROUND TO THE ESE, THEN THE SSE BY 06Z/2A SAT
NIGHT/SUN MORNING WITH SPEEDS AOB 10 KT. THEREAFTER, GOOD MODEL
AGREEMENT IN SETTING UP A RATHER STAGNANT, BUT FAIRLY BENIGN PATTERN
FROM LATE SUN THROUGH THE MIDDLE OF NEXT WEEK. SSW WINDS WL AVERAGE
AOB 15KT OUTSIDE OF ANY DEVELOPING AFTN/EVENING CONVECTION. WAVES
1-2 FT ON THE BAY/SND/RVRS...SEAS GENERALLY 2-4 FT (HIGHEST NORTHERN
COASTAL WATERS).
&&
.AKQ WATCHES/WARNINGS/ADVISORIES...
MD...MODERATE RIP CURRENT RISK THROUGH THIS EVENING FOR MDZ025.
NC...MODERATE RIP CURRENT RISK THROUGH THIS EVENING FOR NCZ102.
VA...MODERATE RIP CURRENT RISK THROUGH THIS EVENING FOR VAZ098>100.
MARINE...NONE.
&&
$$
SYNOPSIS...JAB
NEAR TERM...JAB
SHORT TERM...JAB
LONG TERM...LKB
AVIATION...MAM
MARINE...MAM
AREA FORECAST DISCUSSION
NWS WAKEFIELD VA
344 AM EDT SAT JUN 22 2013
.SYNOPSIS...
A WEAK AREA OF LOW PRESSURE WILL LINGER ALONG THE NORTH CAROLINA
COAST THROUGH TODAY. HIGH PRESSURE WILL BE ANCHORED OFF THE MID
ATLANTIC COAST SUNDAY THROUGH THE MIDDLE OF NEXT WEEK.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
INTERESTING FORECAST CHALLENGES TODAY. HAVE CONVECTION DEVELOPING
ALONG A COASTAL FRONT OVER NORTH CAROLINA AND SLOWLY MOVING NORTH.
THIS IS ASSOCIATED WITH A WEAK PV MAX ALOFT AND CAN BE SEEN ON
WATER VAPOR. MEANWHILE HAVE A WEAK RIDGE OF HIGH PRESSURE ALOFT
JUST TO THE NORTH OF THIS FEATURE. THIS HIGH IS SLOWLY WEAKENING
AND MOVING TO THE EAST. THIS WILL ALLOW THE WEAK TROF TO LIFT
NORTH TODAY. CAN SEE WINDS BECOMING MORE SOUTHEAST ALOFT ON VWP
OBSERVATIONS AROUND THE AREA. THIS WILL ADVECT PLENTY OF MOISTURE
INTO THE SOUTHERN PART OF THE CWA TODAY. WILL FOLLOW THE HRRR IDEA
OF MOVING THE PRECIPITATION FROM NORTH CAROLINA INTO SOUTHEAST
VIRGINIA DURING THE MORNING. COULD SEE SOME BRIEF HEAVY RAIN WITH
SOME OF THE SHOWERS. BY THIS AFTERNOON THE MOISTURE WILL BE PULLED
NORTH OVER MOST OF THE CWA. HOWEVER THE UPPER TROF WILL BE
WEAKENING AND THIS WILL CAUSE THE PRECIPITATION TO MORE SCATTERED.
THIS FOLLOWS THE NAM AND GFS. ALSO THE SREF SHOWS THE BEST CHANCES
FOR PRECIP MOVING TO THE WESTERN SECTIONS OF THE CWA DURING THE
AFTERNOON AND EVENING. SINCE WESTERN AREAS WILL BE SLOWER TO CLOUD
UP WILL HAVE SOME MORE CAPE TO AIDE IN THUNDERSTORM DEVELOPMENT.
AGAIN WITH PLENTY OF MOISTURE AROUND COULD SEE SOME BRIEF HEAVY
DOWNPOURS. TEMPERATURES WILL BE DEPENDENT ON THE AMOUNT OF CLOUD
COVER TODAY. EXPECT TO KEEP MAXES AROUND 80 SOUTHEAST BUT REACH
THE MID 80S ACROSS WESTERN SECTIONS. AGAIN THIS IS CLOSE TO MOS GUIDE.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH MONDAY/...
A SECOND UPPER LOW OVER GEORGIA TODAY WILL SLOWLY LIFT NORTH LATE
TONIGHT AND MOVE ACROSS TO THE WEST OF THE AREA ON SUNDAY. THE
UPPER LOW AGAIN WILL BE WEAKENING AS IT MERGES WITH THE WESTERLY
TO THE NORTH. THIS THIS WILL HELP TO KEEP BEST CHANCES OF SHOWERS
AND THUNDERSTORMS IN THE WESTERN AREAS TONIGHT AND SATURDAY. WITH
THE HIGH PRESSURE CENTERED OFF THE MID ATLANTIC COAST WILL HAVE
MOISTURE FEED OFF THE WATER COMING INTO THE AREA WITH SOME RISE TO
THE EAST WINDS AS THEY APPROACH THE RIDGES TO THE WEST. BY MONDAY
THIS FEATURE IS WEAKENING AND MORE NORTHEAST AWAY FROM THE AREA.
HOWEVER WILL STILL HAVE PLENTY OF MOISTURE ACROSS THE AREA SO WILL
CONTINUE CHANCE TO SLIGHT CHANCE POPS ESPECIALLY ON MONDAY
AFTERNOON WITH THE BEST CHANCES IN THE WEST WHERE THE LOW LEVEL
EAST WINDS WILL BEGIN TO RISE AS THEY APPROACH THE MOUNTAINS TO
THE WEST. WILL GO FAIRLY CLOSE TO MOS GUIDANCE FOR TEMPERATURES
WITH THE WARMEST DAY ON MONDAY AS LESS CLOUD COVER THEN. LOWS AT
NIGHT WILL MAINLY BE IN THE MID TO UPPER 60S.
&&
.LONG TERM /MONDAY NIGHT THROUGH FRIDAY/...
PERIOD BEGINS WITH A BROAD MID/UPPER LEVEL RIDGE CENTERED OVER
MUCH THE SOUTHERN TIER OF THE CONUS...GRADUALLY EVOLVING INTO A
STRONG RIDGE OVER THE SW STATES WITH A FAIRLY DEEP TROUGH CENTERED
JUST NORTH OF THE GREAT LAKES ACRS ONTARIO CANADA. THIS WILL
TRANSLATE INTO A W/NW UPPER FLOW PATTERN INTO THE MID ATLC STATES.
WHILE A SERIES OF WEAK SHORTWAVES BEGIN TO SHUNT THE RIDGE OFF TO
THE S/SW OF THE CWA TUE/WED...TIMING THESE FEATURES IN THE MEDIUM
RANGE IS QUITE DIFFICULT SO WILL GENLY HAVE ONLY A 20% CHANCE FOR
MAINLY DIURNAL/AFTN/EVENING TSTMS TUE/WED. TEMPERATURES WILL WARM
TO A LITTLE ABOVE AVG FOR LATE JUNE...MAINLY IN THE UPPER 80S TO
LOWER 90S FOR HIGHS WITH LOWS IN THE UPPER 60S TO LOWER 70S. BY
THU/FRI...A MORE DEFINED SFC BOUNDARY SETS UP NOT TOO FAR TO THE
NORTH OF THE CWA...AND 500 MB HEIGHTS SLOWLY FALL...SO HAVE POPS
HIGHER THAN CLIMO BOTH DAYS (ESPECIALLY FRI). HIGHS IN THE UPPER
80S TO LOWER 90S AND LOWS MAINLY FROM 70-75.
&&
.AVIATION /07Z SATURDAY THROUGH WEDNESDAY/...
MODELS CONT TO SHOW A PERSISTENT NE FLOW AHEAD OF APPRCHG SYSTM
FROM THE SOUTH. ANOTHER STRATUS LAYER DVLPNG IN ASSOCIATION WITH
REMNANT LLVL MOISTURE TRAPPED BELOW NOCTURNAL INVERSION. THIS WL
LIKELY BRING ANOTHER NIGHT OF IFR VSBYS W/PATCHY FOG. AS LLVL
MOISTURE CONTINUES TO INCREASE, EXPECT IFR TO BE A BIT MORE
WIDESPREAD THIS MORNING THAN THE PREVIOUS TWO.
ASIDE FROM THE FOG, EXPECT SHRAS TO PUSH NW FROM COASTAL CAROLINAS
TOWARDS COASTAL TERMINALS, AND HV LEANED ON HRRR IN TAKING THE
PARENT LOW AND THE ASSOCIATED PCPN SHIELD N-NW INTO NE NC AFTR 12Z
THIS MORNING. PREDOMINATE -RA/SHRA NOW IN THE TAF AT PHF/ECG/ORF
AFTER 13Z, EVENTUALLY REACHING RIC AFTER 15Z. DO EXPECT TO SEE SOME
BREAKS IN STRATUS AT RIC/SBY AFTER 13-15Z, BUT HV GONE WITH VICINITY
SHRA WORDING FOR SCT SHWRS THAT ARE EXPECTED TO DEVELOP BY ERY SAT
AFTN IVOF RIC AS LOW PRESSURE SLOWLY WEAKENS TO OUR SOUTH. CIGS WL
GENERALLY RANGE FROM MVFR TO VFR THROUGH THE AFTN
OUTLOOK: MORE LATE NIGHT STRATUS IS EXPECTED LATE TONIGHT/SUN
MORNING. OTHERWISE, EXPECT PREDOMINATE VFR CONDITIONS ASIDE FROM
SCATTERED MAINLY DIURNALLY DRIVEN SHRAS SUN AND THROUGH MIDWEEK
AS BREEZY S-SW FLOW REDEVELOPS MON-TUE.
&&
.MARINE...
LATEST OBS CONTINUE TO INDICATE E/NE FLOW ACRS THE ENTIRE REGION.
WINDS ARE GENLY 15 KT OR LESS (LIGHTEST OVER NORTHERN AREAS). SEAS
CONTINUE TO SLOWLY SUBSIDE THIS MORNING, NOW AOB 4FT ACROSS THE
MID-ATLANTIC WATERS.
NO MAJOR CHANGES TO THE GOING FORECAST WITH THIS PACKAGE. MSAS 3-HR
PRESSURE FALLS CONTINUES TO SHOW SLOW WEAKENING/SLACKENING OF THE
PRESSURE GRADIENT BETWEEN THE INVERTED SFC TROUGH/LOW NEAR KILM AT
08Z AND HIGH PRESSURE OFF NORTHERN MID-ATLANTIC COAST. ACCORDINGLY,
CONTINUE TO EXPECT CONDITIONS TO REMAIN SUB-SCA TODAY. STILL RATHER
UNFAVORABLE BOATING CONDITIONS TODAY, WITH PREDOMINATE LLVL FLOW OUT
OF THE E/NE FLOW AGAIN TODAY WITH SEAS 4 FT AND WAVES 2-3 FT AT THE
MOUTH OF THE BAY.
AS COASTAL FRONT, PUSHES BACK WEST, EXPECT WINDS TO GRADUALLY SHIFT
TO THE ESE THEN THE SSE BY SAT NIGHT/SUN (AND SPEEDS WILL AVG AROUND
10 KT). GOOD MODEL AGREEMENT IN SETTING UP A RATHER STAGNANT, BUT
FAIRLY BENIGN PATTERN FROM LATE SUN THROUGH THE MIDDLE OF NEXT WEEK
WITH SSW WINDS AVERAGING 10-15 KT OUTSIDE OF ANY CONVECTION. 1-2 FT
ON THE BAY/SND/RVRS...SEAS GENERALLY 2-4 FT (HIGHEST NORTHERN
COASTAL WATERS).
&&
.AKQ WATCHES/WARNINGS/ADVISORIES...
MD...MODERATE RIP CURRENT RISK THROUGH THIS EVENING FOR MDZ025.
NC...MODERATE RIP CURRENT RISK THROUGH THIS EVENING FOR NCZ102.
VA...MODERATE RIP CURRENT RISK THROUGH THIS EVENING FOR VAZ098>100.
MARINE...NONE.
&&
$$
SYNOPSIS...JAB
NEAR TERM...JAB
SHORT TERM...JAB
LONG TERM...LKB
AVIATION...MAM
MARINE...MAM
AREA FORECAST DISCUSSION
NWS WAKEFIELD VA
327 AM EDT SAT JUN 22 2013
.SYNOPSIS...
A WEAK AREA OF LOW PRESSURE WILL LINGER ALONG THE NORTH CAROLINA
COAST THROUGH SATURDAY. HIGH PRESSURE WILL BECOME ANCHORED OFF THE MID
ATLANTIC COAST SUNDAY THROUGH THE MIDDLE OF NEXT WEEK.
&&
.NEAR TERM /UNTIL 6 AM THIS MORNING/...
SFC HIGH PRESSURE EXTENDS OVER THE REGION FROM THE NORTHEAST
TONIGHT. MEANWHILE...AN INVERTED TROUGH/COASTAL FRONT REMAINS OFF
THE CAROLINA COAST. NOT EXPECTING MORE THAN MAINLY ISOLD SHWRS
ACROSS SERN AREAS OVRNGT WITH THE INVERTED TROUGH LINGERING OFF
THE COAST. WE WILL HOWEVER SEE CLOUDS START TO INCREASE FATHER
WEST INTO THE PIEDMONT AS EASTERLY FLOW DEEPENS. NUISANCE LOW
STRATUS/PATCHY FOG WILL ALSO DEVELOP ACROSS THE SOUTHEAST. LOWS
TONIGHT IN THE UPR 50S NW TO THE UPR 60S SERN COASTAL AREAS.
&&
.SHORT TERM /6 AM THIS MORNING THROUGH MONDAY/...
INVERTED TROUGH/COASTAL FRONT WILL LIFT NW AND WEAKEN ALONG THE NC
COAST SATURDAY. BEST LOW-LEVEL MOISTURE STARTS TO SHIFT INLAND
ACROSS SOUTH-CENTRAL VA AND NE NC...AND WE`LL ACTUALLY CARRY CHC
POPS (40-45%) ACROSS THESE AREAS. DESPITE LIMITED FORCING...PWAT`S
AROUND 2 INCHES AND MODEST INSTABILITY (CAPE 1000-1500 J/KG)WILL
HELP GENERATE SOME AFTN THUNDERSTORMS WITH POTENTIAL FOR HEAVY
DOWNPOURS. BECOMING MORE HUMID WITH HIGHS IN THE 80S...EXCEPT
COOLER 70S IMMEDIATE COAST. PCPN WILL WANE WITH THE LOSS OF
DAYTIME HEATING SATURDAY EVENING. LOWS SATURDAY NIGHT IN THE 60S.
A RETURN TO A MORE TYPICAL SUMMERTIME PATTERN IS EXPECTED SUNDAY
INTO MONDAY AS THE COASTAL BOUNDARY IS REPLACED BY BERMUDA HIGH
PRESSURE. THERE WILL BE ENOUGH LINGERING MOISTURE FOR SCT AFTN
CONVECTION BOTH DAYS...ESPECIALLY INLAND...AND WILL COVER THIS
WITH 30% POPS. SEASONABLY WARM AND HUMID WITH HIGHS IN THE 80S TO
AROUND 90...EXCEPT COOLER AT THE BEACHES.
&&
.LONG TERM /MONDAY NIGHT THROUGH FRIDAY/...
PERIOD BEGINS WITH A BROAD MID/UPPER LEVEL RIDGE CENTERED OVER
MUCH THE SOUTHERN TIER OF THE CONUS...GRADUALLY EVOLVING INTO A
STRONG RIDGE OVER THE SW STATES WITH A FAIRLY DEEP TROUGH CENTERED
JUST NORTH OF THE GREAT LAKES ACRS ONTARIO CANADA. THIS WILL
TRANSLATE INTO A W/NW UPPER FLOW PATTERN INTO THE MID ATLC STATES.
WHILE A SERIES OF WEAK SHORTWAVES BEGIN TO SHUNT THE RIDGE OFF TO
THE S/SW OF THE CWA TUE/WED...TIMING THESE FEATURES IN THE MEDIUM
RANGE IS QUITE DIFFICULT SO WILL GENLY HAVE ONLY A 20% CHANCE FOR
MAINLY DIURNAL/AFTN/EVENING TSTMS TUE/WED. TEMPERATURES WILL WARM
TO A LITTLE ABOVE AVG FOR LATE JUNE...MAINLY IN THE UPPER 80S TO
LOWER 90S FOR HIGHS WITH LOWS IN THE UPPER 60S TO LOWER 70S. BY
THU/FRI...A MORE DEFINED SFC BOUNDARY SETS UP NOT TOO FAR TO THE
NORTH OF THE CWA...AND 500 MB HEIGHTS SLOWLY FALL...SO HAVE POPS
HIGHER THAN CLIMO BOTH DAYS (ESPECIALLY FRI). HIGHS IN THE UPPER
80S TO LOWER 90S AND LOWS MAINLY FROM 70-75.
&&
.AVIATION /07Z SATURDAY THROUGH WEDNESDAY/...
MODELS CONT TO SHOW A PERSISTENT NE FLOW AHEAD OF APPRCHG SYSTM
FROM THE SOUTH. ANOTHER STRATUS LAYER DVLPNG IN ASSOCIATION WITH
REMNANT LLVL MOISTURE TRAPPED BELOW NOCTURNAL INVERSION. THIS WL
LIKELY RESULT IN ANOTHER NIGHT OF IFR VSBYS W/PATCHY FOG. AS LLVL
MOISTURE CONTINUES TO INCREASE, EXPECT IFR TO BE A BIT MORE
WIDESPREAD TONIGHT THAN THE PREVIOUS TWO.
ASIDE FROM THE FOG, EXPECT SHRAS TO PUSH NW TOWARDS COASTAL ZONES,
AND HV LEANED ON HRRR IN TAKING THE PARENT LOW AND THE ASSOCIATED
PCPN SHIELD N-NW INTO NE NC AFTR 12Z. PREDOMINATE -RA/SHRA NOW IN
THE TAF AT PHF/ECG/ORF AFTER 13Z. EXPECT SOME BREAKS IN STRATUS AT
RIC/SBY AFTER 13-15Z, BUT HV GONE WITH VICINITY SHRA WORDING FOR
SCT SHWRS THAT ARE EXPECTED TO DEVELOP BY ERY SAT AFTN IVOF RIC
AS LOW PRESSURE SLOWLY WEAKENS TO OUR SOUTH. CIGS WL GENERALLY
RANGE FROM MVFR TO VFR THROUGH THE AFTN
OUTLOOK: MORE LATE NIGHT STRATUS IS EXPECTED LATE TONIGHT/SUN
MORNING. OTHERWISE, EXPECT PREDOMINATE VFR CONDITIONS ASIDE FROM
SCATTERED MAINLY DIURNALLY DRIVEN SHRAS SUN AND THROUGH MIDWEEK
AS BREEZY S-SW FLOW REDEVELOPS MON-TUE.
&&
.MARINE...
LATEST OBS INDICATE E/NE FLOW PREVAILS ACRS THE ENTIRE REGION.
WINDS ARE GENLY 15 KT OR LESS (LIGHTEST OVER NORTHERN AREAS). HAVE
DECIDED TO KEEP SCA IN EFFECT THROUGH 7 PM OVER THE NC COASTAL
WATERS FOR 4-5 FT SEAS (ALTHOUGH FOR THE MOST PART SEAS HAVE
AVERAGED JUST BELOW 5 FT). ELSEWHERE...SEAS ARE 3-4 FT ON THE
COASTAL WATERS, 1-2 FT ON THE BAY/SND/RVRS.
MODELS GENLY FORECAST A SLOW WEAKENING OF THE PRESSURE GRADIENT
BETWEEN THE INVERTED SFC TROUGH/LOW OFF THE NC/SC COAST AND HIGH
PRESSURE OFF THE NJ COAST LATER TONIGHT INTO SAT...SO CONDITIONS
SHOULD NE SUB-SCA THROUGHOUT. THE E/NE FLOW WITH SEAS 4 FT AND
WAVES 2-3 FT AT THE MOUTH OF THE BAY WILL STILL TRANSLATE TO LESS THAN
IDEAL BOATING CONDITIONS ACROSS THE LOWER BAY AND COASTAL WATERS
INTO SAT AFTN HOWEVER.
WINDS GRADUALLY SHIFT TO THE ESE THEN THE SSE BY SAT NIGHT/SUN
(AND SPEEDS WILL AVG AROUND 10 KT). A RATHER STAGNANT, BUT FAIRLY
BENIGN PATTERN IS EXPECTED TO TAKE SHAPE FROM LATE SUN THROUGH THE
MIDDLE OF NEXT WEEK WITH SSW WINDS AVERAGING 10-15 KT OUTSIDE OF
ANY CONVECTION. 1-2 FT ON THE BAY/SND/RVRS...SEAS GENERALLY 2-4
FT (HIGHEST NORTHERN COASTAL WATERS).
&&
.AKQ WATCHES/WARNINGS/ADVISORIES...
MD...MODERATE RIP CURRENT RISK THROUGH THIS EVENING FOR MDZ025.
NC...MODERATE RIP CURRENT RISK THROUGH THIS EVENING FOR NCZ102.
VA...MODERATE RIP CURRENT RISK THROUGH THIS EVENING FOR VAZ098>100.
MARINE...NONE.
&&
$$
SYNOPSIS...JDM
NEAR TERM...JDM/MAS
SHORT TERM...JDM/TMG
LONG TERM...LKB
AVIATION...MAM
MARINE...LKB
AREA FORECAST DISCUSSION
NWS DETROIT/PONTIAC MI
201 AM EDT SAT JUN 22 2013
.AVIATION...
//DISCUSSION...
THE QUESTION ON WHAT WILL BECOME OF THE CONVECTION OVER SOUTHERN
WISCONSIN IS THE MAIN FOCUS FOR THE TAFS THIS MORNING. THE
UPSTREAM THUNDERSTORM ACTIVITY SEEMS TO BE FOCUSING ON EDGE OF
CAP (SEE 00Z KDVN RAOB) FORCED BY LOCALIZED CVA. THE SHORTWAVE
ENERGY IS A RECYCLED CONVECTIVE VORT MAX THAT HAS EMERGED FROM THE
SOUTH. COLUMN MEAN FLOW OVER SOUTHERN WISCONSIN IS ACTUALLY QUITE
WEAK AS THE LOW LEVEL JET IS WEAK WITHIN THE UPPER LEVEL RIDGE.
CORFIDI VECTORS THROUGH MUCH OF THE MORNING ARE FROM THE EAST
WHICH CORRESPONDS WELL TO THE BACKBUILDING BEHAVIOR SEEN RECENTLY.
THIS LEAVES SERIOUS DOUBT IN POTENTIAL FOR THUNDERSTORMS TO
MIGRATE EASTWARD INTO SOUTHEASTERN MICHIGAN. NEVERTHELESS..00Z
KDTX RAOB SUGGESTS THAT EFFERVESCING WEAK CONVECTION MAY BE
POSSIBLE THIS MORNING OVER THE NORTHERN CWA WITH NOTHING MORE THAN
A MODEST INCREASE IN MOISTURE AND ASSOCIATED CLOUD TOP COOLING.
FOR NOW WILL MAINTAIN FORECAST CONTINUITY AND CONVERT PROB30 TO
TEMPO.
AT KDTW...QUIET WEATHER IS EXPECTED THROUGH THE MORNING HOURS. ANY
SHOWER OR THUNDERSTORM ACTIVITY THAT DEVELOPS IS EXPECTED TO
REMAIN NORTH OF THE DETROIT METRO AREA CLOSER TO THE MOISTURE
GRADIENTS.
//DTW THRESHOLD THREATS...
* LOW CONFIDENCE FOR A BRIEF PERIOD OF CEILINGS AT 5KFT SATURDAY
MORNING.
* LOW CONFIDENCE IN THUNDERSTORMS SATURDAY AFTERNOON.
&&
.PREV DISCUSSION...ISSUED 958 PM EDT FRI JUN 21 2013
UPDATE...
CLOUD SHIELD FROM THE LONG-LIVED MCS...NOW POSITIONED OVER SW
INDIANA WHITTLING INTO THE DEEP INSTABILITY RESERVOIR...HAS
QUICKLY DISSIPATED OVER SOUTHEAST MICHIGAN IN THE BROAD UPPER-
LEVEL ANTI-CYCLONIC FLOW. RETURN DEEP THETA-E ADVECTION IS
ALREADY EVIDENT...IN THE FORM OF FRESH SHOWER DEVELOPMENT...NEAR
LAKE MICHIGAN. THIS INITIAL FEATURE IS EXPECTED TO SLIDE EAST AND
SLOWLY WASH OUT IN THE POST-MIDNIGHT HOURS. WHILE THIS OCCURS
GREATER THETA-E ADVECTION IN THE 925-850MB LAYER...OWING FROM AN
INCREASING NOCTURNAL LOW-LEVEL JET...WILL FILTER INTO THE LOWER
PENINSULA LATE TONIGHT. LATEST RAP SOLUTIONS INDICATE 0-1KM MLCAPE
VALUES CLIMBING TO NEAR 1KJ/KG BY DAYBREAK AND INCREASE FROM THERE
THROUGH THE MORNING HOURS. THE SHARP INSTABILITY GRADIENT WILL
QUICKLY TAKE RESIDENCE ACROSS AREAS ALONG AND NORTH OF I-69.
EXPECT NEW CONVECTION TO CONTINUE TO CYCLE ALONG THE SURGE OF
INSTABILITY ACROSS WISCONSIN AND WESTERN LOWER MICHIGAN AS WARM
FRONTAL DYNAMICS WILL AID IN FORCING ASCENT. FARTHER UPSTREAM
ORGANIZED CONVECTION SHOULD CONTINUE ALONG THE SHARP INSTABILITY
GRADIENT OVER SOUTHEAST MINNESOTA AND CENTRAL WISCONSIN. EXPECT
SOME OF THIS ACTIVITY TO CHURN EAST ALONG THE WELL DEFINED
INSTABILITY GRADIENT THROUGHOUT THE NIGHT AND INTO SATURDAY
MORNING.
PREV DISCUSSION...ISSUED 347 PM EDT FRI JUN 21 2013
SHORT TERM...TONIGHT
SOUTHEAST MICHIGAN REMAINS ON THE OUTER FRINGE OF THE UPPER LEVEL
RIDGE CENTERED OVER MISSOURI (SECOND RIDGE CENTER OVER MID
ATLANTIC)...WHICH MAKES FOR A DIFFICULT FORECAST AS 500 MB HEIGHT
HOVERS AROUND THE NORMALLY CRITICAL VALUE OF 588 DAM.
NONE-THE-LESS...700 MB TEMPS REMAIN BELOW 10 C THROUGH
TONIGHT...WHICH SUGGEST ACTIVITY IS POSSIBLE/NOT FULLY CAPPED.
THE MASSIVE AND LONG LIVED MCS WHICH DEVELOPED OVER THE WESTERN
GREAT LAKES THIS MORNING CONTINUES TO WEAKEN...WITH REMNANT 500 MB
LOW/TROUGH TRACKING THROUGH NORTHERN LOWER MICHIGAN EARLY THIS
EVENING. LATEST RADAR TRENDS SUGGEST A FEW SHOWERS AND POSSIBLE
THUNDERSTORMS MAY SURVIVE THE TRIP ACROSS THE STATE...AS THERE IS
SOME MODEST CAPES (SB CAPES OF 1000 J/KG)/INSTABILITY THE RAIN
COOLED AIRMASS WILL BE MOVING INTO. ON THE FLIP SIDE...DEW PTS ARE
MIXING DOWN INTO THE 50S ACROSS NORTHERN INDIANA/NW OHIO AND INTO
PARTS OF SOUTHERN LOWER MICHIGAN...INDICATIVE OF THE 850-700 MB
THETA-E TROUGH ASSOCIATED WITH THE RIDGE CENTER OVER THE MID
ATLANTIC STATES...AND THUS THE DIRECTION THE FORECAST IS SKEWED WITH
JUST SLIGHT CHANCE POPS SOUTH TO CHANCE POPS NORTH.
THE QUESTION THEN BECOMES WHAT TO DO WITH TONIGHT...AS WISCONSIN LOW
TRACKS NORTHEAST...ALLOWING FOR A DECENT 850 MB JET OF 40+ KNOT TO
SET UP OVER NORTHERN LOWER MICHIGAN THIS EVENING. GOOD
DESTABILIZATION TO REDEVELOP OVER THE WESTERN GREAT LAKES...WITH
ANOTHER MCS DEVELOPING OVER THE EASTERN DAKOTAS THIS AFTERNOON...AND
IT CERTAINLY IS POSSIBLE THIS COMPLEX WILL ARRIVE IN A WEAKENED
STATE OVER LOWER MICHIGAN LATER TONIGHT...DESPITE THE 12Z NAM
INDICATING DISSIPATION OVER WISCONSIN THIS EVENING. EVEN IF THIS
DOES NOT OCCUR...STILL A CHANCE THE LOW LEVEL JET WILL TRIGGER A FEW
SHOWERS/THUNDERSTORMS WITH MOISTURE AXIS MOVING
OVERHEAD...ESPECIALLY AS ONE HEADS NORTH TOWARD SAGINAW BAY...CLOSER
TO THE REMNANT WEAK FRONTAL BOUNDARY AND BETTER MOISTURE TRANSPORT.
WITH INCREASING LOW LEVEL MOISTURE...MINS IN THE 60S ARE EXPECTED.
LONG TERM... SATURDAY THROUGH FRIDAY
EVOLUTION OF CONVECTION OVER THE MIDWEST AND GREAT LAKES REMAINS THE
PRIMARY FORECAST CHALLENGE THROUGH THE WEEKEND AS A MID SUMMER AIR
MASS SPREADS OVER THE REGION. SATELLITE IMAGERY AND MODEL ANALYSIS
FIELDS INDICATE THE CONVECTIVE COMPLEX FROM THIS MORNING YIELDED A
SUBSTANTIAL MCV NOW OVER THE NORTHERN GREAT LAKES BUT WHICH WILL
MOVE EAST IN TIME FOR EITHER THE ONGOING NORTHERN PLAINS
CONVECTION TO MOVE EASTWARD OR FOR A NEW ROUND OF NOCTURNAL
DEVELOPMENT OVER THE UPPER MIDWEST TONIGHT. THE GENESIS REGION
WILL BE FARTHER EAST COMPARED TO LAST NIGHT, MIGRATING WITH THE
LARGE SCALE SURFACE TROUGH FROM THE NORTHERN PLAINS/DAKOTAS INTO
MINNESOTA/NORTHERN WISCONSIN. EXPECT A RESURGENT LOW LEVEL JET TO
FORCE NEW CONVECTION BY LATE THIS EVENING, OR SUPPORT THE ONGOING
STORMS MOVING IN FROM THE DAKOTAS, EITHER OF WHICH WILL HAVE A
CHANCE TO REACH CENTRAL/SE MICHIGAN DURING SATURDAY MORNING.
INITIATION/PERSISTENCE OF EVENING CONVECTION WILL BE FAVORED ALONG
EDGE OF THE MID LEVEL CAP, SUPPORTED BY OBSERVATIONS TO BE ROUGHLY
IN THE 8-10C RANGE AT 700 MB AND AROUND 18C AT 850 MB. THIS, ALONG
WITH A WESTERLY MEAN FLOW WILL SET UP A GENERAL WEST TO EAST
DEVELOPMENT OF STORMS INTO SATURDAY MORNING. LOWER MICHIGAN WILL
BE MORE RECEPTIVE TO MCS PERSISTENCE BY THEN DUE TO INCREASED
POTENTIAL INSTABILITY IN THE WARM SECTOR OVER THE REGION, AT LEAST
COMPARED TO THIS MORNING, BUT WITH THE INSTABILITY AXIS GENERALLY
WEAKENING FROM WEST TO EAST OVER THE GREAT LAKES. THE KEY TO
COVERAGE IN SE MICHIGAN MIGHT BE TIED TO THE INSTABILITY
GRADIENT/CAP TAKING ON MORE OF WEST TO EAST CONFIGURATION AS THE
WARM FRONT MOVES INTO THE NORTHERN GREAT LAKES, WHICH FAVORS THE
TRI CITIES AND NORTHERN THUMB WITH THE GREATEST CHANCE OF STORMS.
SEVERE WEATHER POTENTIAL REMAINS ON THE LOW SIDE AS A MATURE
COMPLEX WILL BE POSSIBLE BUT, AS MENTIONED ABOVE, EXPECTED TO BE
MOVING INTO WEAKER ENVIRONMENT OF INSTABILITY AND MID LEVEL LAPSE
RATES. BULK SHEAR IN THE 0-6 KM LAYER IS ALSO UNFAVORABLE AT
GENERALLY LESS THAN 20 KNOTS AS THE LARGER SCALE RIDGE BUILDS OVER
THE REGION.
CONDITIONS WILL BECOME INCREASINGLY CAPPED FOR THUNDERSTORM ACTIVITY
DURING SATURDAY AFTERNOON THROUGH SUNDAY. AFTER NOCTURNAL CONVECTION
EXITS/DISSIPATES SATURDAY MORNING, MODERATE SOUTHWEST LOW LEVEL FLOW
WILL DISSIPATE ANY LINGERING OUTFLOW BOUNDARIES AND WORK AGAINST
LAKE BREEZE FORMATION/INLAND PENETRATION. ALL OF THIS WILL OCCUR AS
THE UPPER LEVEL RIDGE BUILDS OVER LOWER MICHIGAN AND REINFORCES WARM
AIR THROUGH THE MID LEVELS. THE NEW 12Z RUNS ARE IN GOOD GENERAL
AGREEMENT ON THE CHARACTER OF THE RIDGE WITH 500 MB HEIGHT BUILDING
INTO THE 588-591 RANGE BY SATURDAY NIGHT INTO SUNDAY. THIS WILL
SUPPORT THE RECENTLY ADVERTISED HEAT AND HUMIDITY FOR THE REST OF
THE WEEKEND. SURFACE DEWPOINT PUSHING 70F WILL BOOST HEAT INDEX INTO
THE LOWER 90S SATURDAY AFTERNOON AND TOWARD THE MID 90S SUNDAY WITH
GREATER CONFIDENCE THAT CLOUD COVER WILL HAVE MINIMAL IMPACT ON
AFTERNOON MAX TEMPS.
THE LARGE SCALE PATTERN WILL SUPPORT PERSISTENCE OF WARM AND HUMID
CONDITIONS INTO NEXT WEEK. THE MAIN SOURCE OF FORECAST UNCERTAINTY
DURING MONDAY AND TUESDAY WILL BE WITH THE EVOLUTION OF A WEAK UPPER
LEVEL CIRCULATION NOW OVER THE SOUTHEAST STATES. GLOBAL MODELS
INDICATE THIS FEATURE SLOWLY DRIFTING INTO THE WESTERLIES AS A NEW
SHORT WAVE SLIDES INTO NORTHERN ONTARIO. THE ABSORPTION OF THE UPPER
CIRCULATION OVER THE EASTERN GREAT LAKES WILL COMBINE WITH THE
POTENTIAL FOR A DECAYING FRONTAL BOUNDARY TO SETTLE OVER THE REGION
AND REQUIRE A CONTINUED CHANCE MENTION OF SHOWERS AND STORMS. THERE
REALLY IS NO CONVINCING MODEL SOLUTION THAT OFFERS A SIGNIFICANT
CHANGE OF AIR MASS DURING THE SECOND HALF OF NEXT WEEK UNTIL
PERHAPS FRIDAY. THE LONG WAVE PATTERN IS SHOWN TO RETROGRADE
ENOUGH BY THEN AND OPEN THE DOOR ON A CANADIAN AIR MASS HEADING
INTO NEXT WEEKEND.
MARINE...
GENERALLY LIGHT SOUTHERLY WINDS WILL CONTINUE THROUGH THE
WEEKEND...LEADING TO UNSTABLE ATMOSPHERIC CONDITIONS WHICH COULD
TRIGGER THUNDERSTORMS FROM TIME TO TIME. OUTSIDE OF THUNDERSTORM
ACTIVITY, HIGHLY STABLE CONDITIONS CREATED BY THE WARM AIR OVER THE
COOL LAKE WATER WILL MAINTAIN A MUTED RESPONSE TO THE WAVE GROWTH.
&&
.DTX WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LAKE HURON...NONE.
LAKE ST CLAIR...NONE.
MI WATERS OF LAKE ERIE...NONE.
&&
$$
AVIATION.....CB
UPDATE.......MANN
SHORT TERM...SF
LONG TERM....BT
MARINE.......SF
YOU CAN OBTAIN YOUR LATEST NATIONAL WEATHER SERVICE FORECASTS ONLINE
AT WWW.WEATHER.GOV/DETROIT (ALL LOWER CASE).
AREA FORECAST DISCUSSION
NWS DULUTH MN
409 AM CDT SAT JUN 22 2013
.SHORT TERM...TODAY THROUGH SUNDAY.
THE FOCUS FOR TODAY THROUGH SUNDAY WILL CONTINUE TO BE PCPN
POTENTIAL...AS WELL AS THE CONTINUED POTENTIAL FOR FOG AND
DRIZZLE. PORTIONS OF THE CWA ARE ALSO IN THE SLIGHT RISK FOR
SEVERE WEATHER TODAY AND TONIGHT.
AT 330 AM...IT WAS ESSENTIALLY DRY ACROSS THE NORTHLAND. THERE
WERE A FEW LIGHT SHOWERS NORTH OF THE IRON RANGE...AND ALSO IN NW
WI. WIDESPREAD SHOWERS AND THUNDERSTORMS CONTINUED FROM EASTERN
SOUTH DAKOTA...THROUGH CENTRAL AND SOUTHERN MN AND SOUTHERN WI
WITH WIDESPREAD MCS ACTIVITY IN THOSE AREAS. DENSE FOG CONTINUED
NEAR LAKE SUPERIOR AND HAVE ISSUED A DENSE FOG ADVISORY FOR LAND
AND WATER AREAS.
THE BIG QUESTION IS THE EVOLUTION OF THE WIDESPREAD SHOWERS AND
THUNDERSTORMS TO THE SOUTH OF THE AREA. AS EXPECTED WITH THIS TYPE
OF PATTERN...THE MODELS REALLY DO NOT HAVE A HANDLE ON THE CURRENT
PRECIPITATION. THERE ARE A FEW EXCEPTIONS...INCLUDING THE 4 KM WRF
AND THE 06Z HRRR RAPID REFRESH. BOTH HAVE A RELATIVELY DECENT
HANDLE ON THE CURRENT PRECIPITATION TRENDS...AND BOTH BRING THE
PRECIPITATION NORTH AND EASTWARD INTO OUR CWA. HAVE DONE SOME
DRAMATIC MODIFICATIONS TO POPS AND WEATHER FOR TODAY. THE TWO HIGH
RESOLUTION MODELS ACTUALLY LIFT IT INTO THE CWA BUT DECREASE THE
PRECIPITATION GRADUALLY. WILL KEEP THIS TREND GOING. HAVE ALSO
ADDED AREAS OF DRIZZLE AND DENSE FOG NEAR LAKE SUPERIOR...WHICH
WILL LIKELY CONTINUE THROUGHOUT THE DAY IN SOME FORM.
FOR LATER TODAY AND TONIGHT...MOST OF THE MODEL SOLUTIONS DO BRING
A DRAMATIC INCREASE IN PRECIPITATION...AS A FRONTAL BOUNDARY
STRETCHES FROM SW TO NE ACROSS THE AREA. WILL INCREASE POPS LATER
TODAY AND TONIGHT. COULD STILL SEE SOME STRONG TO SEVERE STORMS IF
WE ARE ABLE TO SEE ENOUGH DAYTIME HEATING FOR SURFACE BASED
CONVECTION. THE FAIRLY HIGH CHANCE OF SHOWERS AND THUNDERSTORMS
WILL ALSO CONTINUE ON SUNDAY...AS THE FRONT REMAINS IN THE AREA.
WILL DEFINITELY NEED TO CONTINUE TO MONITOR THE THREAT OF FLOODING
ACROSS THE AREA. PRECIPITABLE WATER VALUES ARE ON THE ORDER OF 1.8
INCHES TODAY INTO SUNDAY...SO THERE IS ABUNDANT AVAILABLE MOISTURE.
TEMPS WILL BE TROUBLESOME TODAY BASED ON CLOUDS AND PCPN TRENDS.
OVERALL WE SHOULD SEE 70S FOR MOST AREAS TODAY AND SOME 80S
SUNDAY. IT WILL BE DRAMATICALLY COOLER NEAR LAKE SUPERIOR WITH
SOME FAIRLY STRONG NORTHEAST WINDS.
.LONG TERM...SUNDAY NIGHT THROUGH FRIDAY NIGHT...
UPPER LOW AND CO-LOCATED SFC LOW WILL MOVE FROM SRN MANITOBA AND WRN
ONTARIO TO THE E/NE ACROSS NRN/CENTRAL ONTARIO SUNDAY NIGHT AND
MONDAY MORNING. A TRAILING COLD FRONT WILL SWEEP ACROSS THE UPPER
MIDWEST AND BRING RAIN SHOWERS AND THUNDERSTORMS TO MUCH OF THE
NORTHLAND THROUGH MON MORNING. HIGH PRESSURE IS EXPECTED TO BUILD IN
ACROSS NRN MN LATE MON AFTERNOON AND INTO MONDAY NIGHT. THIS WILL
ALLOW CONDITIONS TO REMAIN QUIET...AT LEAST UNTIL TUE MORNING WHEN
THE NEXT FRONT IS EXPECTED TO LIFT NWD THROUGH THE REGION AND SPREAD
ANOTHER ROUND OF SHOWERS AND STORMS THROUGH WED EVENING. AN AREA OF
LOW PRESSURE WILL DEVELOP OVER S-CENTRAL CANADA...ON THE NWRN FLANK
OF THE SFC TROUGH/WARM FRONT...AND MOVE EWD INTO NRN ONTARIO ON
THURSDAY. THIS LOW PRESSURE WILL DRAW IN SLIGHTLY COOLER AIR FROM
NRN CANADA AND MODIFY LOW LEVEL THERMAL PROFILES ACROSS NRN MN
ENOUGH TO TRIGGER SHOWERS AND STORMS ACROSS THE REGION THROUGH
FRIDAY.
TEMPERATURES MONDAY THROUGH THURSDAY WILL BE WARM WITH HIGHS IN THE
70S AND 80S...AND 60S AROUND THE PERIPHERY OF LAKE SUPERIOR.
OVERNIGHT LOWS WILL BE MILD WITH TEMPS DROPPING INTO THE UPPER 50S
AND 60S.
&&
.AVIATION.../06Z TAF ISSUANCE/
NEXT FEW HOURS A CLUSTER OF THUNDERSTORMS MAY AFFECT KHYR WITH IFR
CIGS AND MVFR VSBYS. OTHERWISE...LAKE EFFECTS ARE PRODUCING
STRATUS OVER MOST OF THE REGION WITH MVFR CIGS...WITH LIFR AT KDLH.
STRATUS HAS LOTS OF HOLES STILL AT KBRD AND KHYR...AND KINL HAS
NOT BEEN AFFECTED AT ALL. THIS STRATUS LAYER SHOULD CONTINUE
OVERNIGHT WITH SOME MVFR FOG ALSO EXPECTED. KDLH TO REMAIN LIFR IN
FOG AND STRATUS WITH THE LIGHT EAST WINDS CONTINUING. WINDS TO
TURN MORE SOUTHERLY SATURDAY IN THE 15Z-18Z TIME RANGE AND EXPECT
CIGS TO IMPROVE DURING THE DAY. SHOWERS AND THUNDERSTORMS ARE
EXPECTED DURING THE AFTERNOON FOR AT LEAST A SHORT TIME...BUT
TIMING AND LOCATION STILL UNCERTAIN SO HAVE LEFT AS VCTS FOR NOW.
&&
.POINT TEMPS/POPS...
DLH 70 57 77 60 / 60 70 60 60
INL 75 62 77 58 / 50 50 60 60
BRD 81 67 82 61 / 70 70 50 50
HYR 83 69 86 63 / 60 70 60 60
ASX 76 61 83 61 / 60 70 60 60
&&
.DLH WATCHES/WARNINGS/ADVISORIES...
MN...DENSE FOG ADVISORY UNTIL 4 PM CDT THIS AFTERNOON FOR MNZ020-021-
037.
WI...DENSE FOG ADVISORY UNTIL 4 PM CDT THIS AFTERNOON FOR WIZ001>004.
LS...DENSE FOG ADVISORY UNTIL 4 PM CDT THIS AFTERNOON FOR LSZ121-
140>148.
SMALL CRAFT ADVISORY FROM 7 AM THIS MORNING TO 10 PM CDT THIS
EVENING FOR LSZ143>146.
&&
$$
SHORT TERM...DAP
LONG TERM....TENTINGER
AVIATION...TENTINGER
AREA FORECAST DISCUSSION
NWS TWIN CITIES/CHANHASSEN MN
112 AM CDT SAT JUN 22 2013
.SHORT TERM...(THIS EVENING THROUGH SATURDAY)
ISSUED AT 345 PM CDT FRI JUN 21 2013
ANOTHER ACTIVE SHORT TERM IS EXPECTED...WITH POTENTIAL FOR BOTH
ANOTHER SEVERE WEATHER EVENT AND A SIGNIFICANT FLASH FLOOD EVENT
OVER SRN MN BEING CLOSELY MONITORED TONIGHT.
WARM FRONTAL BOUNDARY AT 3PM STRETCHES FROM ROUGHLY MARSHALL OVER
TOWARD RED WING. VERY UNSTABLE AIRMASS COMBINED WITH A WAVE THAT
CAME OUT OF THE BLACK HILLS THIS MORNING HAS SEVER CLUSTER OF STORMS
OVER SODAK THAT IS RAPIDLY APPROACHING SW MN. THE SYSTEM IS STARTING
TO BOW...WITH HURON REPORTING A WIND GUST OF 87 MPH. HAVE BEEN
LEANING ON THE HRRR HEAVILY ALL DAY TO TRACK THIS SYSTEM ACROSS THE
AREA. EXPECT THESE STORMS TO BASICALLY FOLLOW THE WARM FRONT AND
850-300 THICKNESS LINES TO THE ESE ACROSS SRN MN. TORNADO/LARGE HAIL
TREAT WILL BE HIGHEST ALONG THE SODAK BORDER...WITH THE THREAT
TRANSITIONING OVER TO MORE OF A WIND THREAT AS YOU HEAD EAST. WOULD
NOT BE SURPRISED IF BY 5 OR 6 PM WE ARE COORDINATING WITH THE SPC
FOR A SVR THUNDERSTORM WATCH TO THE EAST OF THE CURRENT TOR WATCH.
FOR TONIGHT THOUGH...THE REAL BIG CONCERN IS THE POTENTIAL FOR A
SIGNIFICANT RAINFALL/FLASH FLOODING EVENT ACROSS SRN MN. THE RAP HAS
THE NOSE OF A PERSISTENT 40-50 KT LLJ COMING UP OUT OF THE PLAINS
AND REMAINING MORE OR LESS STATIONARY INTO SW MN. AS THE HRRR
SHOWS...WITH 3000-5000 J/KG OF MUCAPE REMAINING IN PLACE WITH THE
LLJ...THE PROBABILITY FOR ADDITIONAL TSRA DEVELOPMENT BACK INTO THE
SD/NEB/IA AREA THROUGH THE NIGHT WILL BE HIGH. THIS WILL LEAD TO A
THREAT FOR TRAINING OF STORMS TONIGHT...WITH THE POTENTIAL FOR SOME
RATHER SIGNIFICANT RAINFALL TOTALS IN EXCESS OF 6 INCHES POSSIBLE
FOR TONIGHT. GIVEN THE POTENTIAL...HAVE ISSUED A FLASH FLOOD WATCH
FOR AREAS ALONG AND SOUTH OF AN APPLETON TO CHIPPEWA FALLS
LINE...WITH THE POTENTIAL FOR SEEING MULTIPLE ROUNDS OF STORMS IS
HIGHEST. GIVEN THE SOUTHERN POSITION OF THE WARM FRONT...LESSER
AMOUNTS OF RAINFALL ARE CURRENTLY ANTICIPATED OVER CENTRAL MINNESOTA
INTO NW WISCONSIN.
LIKE TODAY...EXPECT ACTIVITY TO WIND DOWN THROUGH THE MORNING ACROSS
THE MPX AREA...WITH MUCH OF THE LATE MORNING INTO THE EARLY
AFTERNOON REMAINING DRY. THE BIG DIFFERENCE THOUGH ON SATURDAY TO
THE PAST TWO DAYS...IS THE SYNOPTIC COLD/STATIONARY FRONT AND LOW
PRESSURE SYSTEM WILL BE FARTHER EAST. BY THE AFTERNOON...MODELS SHOW
A LEE SIDE LOW DEVELOPING OVER ERN COLORADO...WITH A STATIONARY
FRONT/PRESSURE TROUGH EXTENDING TO THE NORTHEAST TOWARD WRN MN. WITH
THE SYNOPTIC FEATURES FARTHER EAST TOMORROW...THIS SHOULD INCREASE
THE CHANCES FOR THUNDERSTORMS DEVELOPING IN THE AFTERNOON ACROSS THE
MPX AREA...WHICH WILL LEAD TO A HIGHER PROBABILITY FOR SEEING
TORNADOES OR HAIL DURING THE AFTERNOON...BEFORE ANOTHER POTENTIAL
ROUND OF STORMS GOING INTO SATURDAY NIGHT.
.LONG TERM...(SATURDAY NIGHT THROUGH FRIDAY)
ISSUED AT 345 PM CDT FRI JUN 21 2013
NO SIGNIFICANT CHANGES FROM THE PREVIOUS FORECAST...WITH SEVERE AND
HYDRO CONCERNS CONTINUING THROUGH EARLY NEXT WEEK. THE UPPER LEVEL
LOW WILL LINGER JUST TO THE WEST...WITH THE SURFACE TROUGH INCHING
EVER CLOSER TO WESTERN MINNESOTA BY THE WEEKEND...AND THE FRONTAL
BOUNDARY STALLED OUT EAST/WEST ACROSS THE FORECAST AREA ONLY TO
OSCILLATE NORTH/SOUTH WITH EACH CONVECTIVE OUTFLOW BOUNDARY. THE
TROPICAL AIRMASS WILL REMAIN IN PLACE THROUGH EARLY NEXT WEEK...WITH
PWAT VALUES IN THE 1.75 TO 2.00 INCH RANGE. SREF 21.09 MLCAPE PLUMES
CONTINUE TO SHOW 2500 TO 4000J/KG DURING THE AFTERNOON...AND THIS
SEEMS REASONABLE CONSIDERING WHAT IS CURRENTLY GOING ON ACROSS
SOUTHWEST MINNESOTA. DEEP LAYER SHEAR WILL ONLY BE IN THE 25KT
RANGE...BUT THE SEVERE WEATHER REMAINS A CONCERN SINCE THE STORMS
MAY BE ABLE TO MODIFY THEIR OWN ENVIRONMENT AS IS THE CASE THIS
AFTERNOON ACROSS EASTERN SOUTH DAKOTA. AS THE SURFACE TROUGH SLOWLY
PROGRESSES EASTWARD...THE POTENTIAL FOR AFTERNOON CONVECTION WILL
INCREASE AS WELL. THEREFORE THE MISSISSIPPI RIVER VALLEY MAY
TRANSITION FROM A PURELY NOCTURNAL EVENT AS WAS THE CASE LAST
NIGHT...TO MORE OF A AFTERNOON AND EVENING FOCUS. FORECAST MODELS
CONTINUE TO SHOW A SHORTWAVE MOVING ACROSS NORTHERN MINNESOTA
SATURDAY NIGHT...SO IF STORMS DO NOT DEVELOP TOMORROW AFTERNOON THEY
WILL CERTAINLY FORM AHEAD OF THAT WAVE. ANOTHER WAVE FOLLOWS FOR
SUNDAY EVENING...SO COULD SEE SOME QUICK REDEVELOPMENT DURING THE
DAY ON SUNDAY.
LOOKING AHEAD...BOTH THE GFS AND ECMWF TRANSITION TO A MORE ZONAL
PATTERN WITH THE H250 JET STRADDLING THE INTERNATIONAL BORDER...AND
CONTINUED CHANCES FOR POPS THROUGH THE MIDDLE OF THE WEEK. THE UPPER
LEVEL RIDGE TRIES TO BUILD ACROSS THE ROCKIES BY LATE NEXT
WEEK...BUT CONFIDENCE IS LOW IN THE DEVELOPMENT OF THIS FEATURE
GIVEN THE CONTINUED DELAYED ONSET WITH EACH MODEL RUN.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT)
ISSUED AT 1249 AM CDT SAT JUN 22 2013
ANOTHER POTENTIALLY ACTIVE 24 HOUR PERIOD EXPECTED...MAINLY IN THE
FIRST 6 HOURS AND THEN IN THE LAST 6 HOURS. CDFNT WOBBLING OVER
THE IA/MN BORDER WILL SLOWLY LIFT N DURG THIS TAF PERIOD.
RAIN/TSTMS ALONG IT OVER MAINLY FAR SRN MN INTO SW WI WILL SLOWLY
SHIFT N THIS MRNG...RESULTING IN DEGRADED CONDS FOR KRWF-KMSP-
KEAU-KRNH. AM THINKING KAXN-KSTC SHOULD STAY OUT OF THE ACTION
THIS MRNG. ONCE THE PRECIP ENDS...WHICH SHOULD BE BY 12Z THIS
MRNG...WILL HAVE A REPRIEVE FROM THE PRECIP AND THERE MAY EVEN BE
A FEW BREAKS IN THE OVC. ONCE THE ATMOS RELOADS ITS
INSTABILITY...LIFT FROM THE NWW-MOVNIG CDFNT AND A CONTINUED MOIST
ATMOS WILL ALLOW FOR RE-DEVELOPMENT OF CONVECTION LATE THIS AFTN
THRU THIS EVE. STILL SOME TIMING ISSUES BUT HAVE GENERALLY
HIGHLIGHTED THE BEST TIMING FOR EACH TAF SITE BASED ON GRIDDED
FORECASTS AND RAP/HRRR MODELS. THESE TEMPO GROUPS AT THE END OF
THE TAFS MAY WELL NEED TO BE ADJUSTED BUT FELT CONFIDENT ENOUGH
ATTM TO AT LEAST HIGHLIGHT THE LIKELY CHC OF TSTMS LATER TDA.
KMSP...GENERALLY LIGHT SHOWERS WITH A SOME IC/CC/CG LIGHTNING OVER
THE FIRST FEW HRS OF THE 06Z TAF THEN PRECIP ACTIVITY WILL WANE
GOING INTO DAYBREAK. PRECIPITATION WILL RESUME LATER THIS EVENING
AND POTENTIALLY INTO THE OVERNIGHT HOURS. STILL SOME TIMING ISSUES
AS TO WHEN BUT HAVE HIGHLIGHTED THE BEST TIMING GIVEN CURRENT
SHORT-TERM MODEL RUNS AND GRIDDED FCSTS. STILL ALSO THE POTENTIAL
FOR WINDS IN EXCESS OF 35 KT LET ALONE THE SLGT RISK FOR SEVERE
TSTMS THIS EVENING AND TNGT.
/OUTLOOK FOR KMSP/
SUN...TSRA LIKELY. VFR OUTSIDE OF TSRA. WINDS SSW 10-15 KTS.
MON...CHC TSRA. VFR OUTSIDE OF TSRA. WINDS S 5-10 KTS.
TUE...CHC TSRA. VFR OUTSIDE OF TSRA. WINDS SSE 10-15 KTS.
&&
.HYDROLOGY...
ISSUED AT 345 PM CDT FRI JUN 21 2013
AS ALLUDED TO EARLIER PWATS WILL BE IN THE 90TH PERCENTILE
THOUGH EARLY NEXT WEEK. THE AREA IS INCREASINGLY VULNERABLE TO BOTH
FLASH FLOODING...AND RIVER FLOODING GIVEN THE WIDESPREAD RAINFALL
AMOUNTS OF 2-4 INCHES FALLING LAST NIGHT. THE EAST/WEST FRONTAL
BOUNDARY SUPPORTS TRAINING THUNDERSTORMS...AND THE H925 MOISTURE
TRANSPORT SURGES NORTHWARD OVERNIGHT AS THE LOW LEVEL JET DECOUPLES
FROM THE BOUNDARY LAYER. CONTINGENCY FORECAST BASED OFF DIFFERENT
QPF SCENARIOS SHOW THE POTENTIAL FOR SIGIFICANT FLOODING BY EARLY
NEXT WEEK ALONG THE QUICKER RESPONSE RIVERS...AND EVENTUALLY THE
LARGER MAIN STEMS OF THE MINNESOTA AND MISSISSIPPI RIVER.
&&
.MPX WATCHES/WARNINGS/ADVISORIES...
MN...FLASH FLOOD WATCH THROUGH THIS AFTERNOON FOR MNZ041>045-047>070-
073>078-082>085-091>093.
WI...FLASH FLOOD WATCH THROUGH THIS AFTERNOON FOR WIZ014>016-023>028.
&&
$$
SHORT TERM...MPG
LONG TERM...JRB
AVIATION...JPC
HYDROLOGY...JRB
AREA FORECAST DISCUSSION...UPDATED AVIATION
NWS ST LOUIS MO
1149 PM CDT FRI JUN 21 2013
.UPDATE...
ISSUED AT 933 PM CDT FRI JUN 21 2013
SCANT CONVECTION THAT DOTTED OUR S IL COUNTIES EARLY THIS EVENING
HAS DISSIPATED...AND AM EXTREMELY HARD-PRESSED TO DISCERN ANY MECHANISM
FOR REDEVELOPMENT OVERNIGHT. STRONGEST 850MB WAA WILL BE FOCUSED
WELL TO OUR N THROUGHOUT THE NIGHT...AND THE MID LEVEL WAA THAT
WAS RESPONSIBLE FOR LAST NIGHTS CONVECTION IS MUCH...MUCH WEAKER
OVER OUR AREA THAN IT WAS LAST NIGHT. SO...WILL GO WITH A DRY
FORECAST FOR REMAINDER OF THE NIGHT WITH SOME OCCASIONAL MID AND
HIGH LEVEL CLOUDINESS. TEMPERATURE TRENDS STILL LOOKING GOOD.
ZONES WILL BE OUT IN A SECOND.
TRUETT
&&
.SHORT TERM...(THROUGH LATE TONIGHT)
ISSUED AT 323 PM CDT FRI JUN 21 2013
THE MAIN SHORT-TERM CONCERN IS THE MCS GENERATED OUTFLOW BOUNDARY
CURRENTLY DROPPING S/SEWD THROUGH CENTRAL IL. WHILE THE MCS
ITSELF IS MOVING SEWD...THE RUC 0-3 KM AND 0-6 KM SHEAR VECTORS
SUGGEST THAT AS LONG AS THIS BOUNDARY MAINTAINS ITS IDENTITY IT
SHOULD CONTINUE TO DROP S/SEWD AND AT LEAST IMPACT AREAS EAST OF
THE MS RIVER LATE THIS AFTERNOON INTO EARLY THIS EVENING. THE AIR
MASS AHEAD OF THIS BOUNDARY IS WEAKLY CAPPED WITH SBCAPE INCREASING
FROM 2000 J/KG IN CENTRAL IL TO NEAR 4000 J/KG ALONG THE RIVER.
THIS COMBINATION OF INSTABILITY/CAPPING AND CONVERGENCE WITH THE
BOUNDARY SUPPORTS A GREATER CHANCE OF MORE ORGANIZED CONVECTION
ACROSS SOUTH CENTRAL IL WHERE SCATTERED THUNDERSTORMS ARE POSSIBLE.
ELSEWHERE THROUGH SUNSET ANY THREAT OF SHOWERS/THUNDERSTORMS WILL
BE ISOLATED PULSE TYPE ACTIVITY ASSOCIATED WITH DIURNAL HEATING. I
THINK THERE WILL THEN BE A LULL FROM SAY AROUND 02-03Z TIL 08Z OR
SO...THEN ANOTHER CHANCE OF SHOWERS AND THUNDERSTORMS...PRIMARILY
ACROSS ERN MO INTO SW/SC IL... ASSOCIATED WITH LOW-MID LEVEL WAA
VIA THE SWLY LLJ AND STEEP MID LEVEL LAPSE RATES. OVERNIGHT LOWS
WILL BE QUITE MILD AND ABOVE SEASONABLE NORMS.
GLASS
.LONG TERM...(SATURDAY THROUGH NEXT FRIDAY)
ISSUED AT 323 PM CDT FRI JUN 21 2013
(SATURDAY THROUGH MONDAY)
BROKEN RECORD FOR WEATHER PATTERN AS WE REMAIN IN WARM SECTOR ON
SATURDAY WITH SOME WEAK INSTABILITY AND PLENTY OF MOISTURE. SO ANY
OLD OUTFLOW BOUNDARY...ETC COULD TRIGGER ISOLATED THUNDERSTORM
DEVELOPMENT...SO KEPT SLIGHT CHANCE POPS FOR SATURDAY AFTERNOON.
OTHERWISE...HIGHS WILL BE IN THE UPPER 80S TO LOW 90S...POSSIBLY IN
THE MID 90S IN THE STL METRO AREA. LOWS SATURDAY NIGHT WILL BE IN
THE LOW 70S.
UPPER RIDGE BUILDS IN A BIT STRONGER ON SUNDAY...SO THUNDERSTORM
CHANCES DIMINISH. BUT HOT AND HUMID CONDITIONS TO PERSIST WITH HIGHS
IN THE UPPER 80S TO LOW 90S. ON SUNDAY NIGHT AND MONDAY...UPPER
RIDGE BEGINS TO WEAKEN AGAIN AS NEXT WEATHER SYSTEM APPROACHES THE
REGION. MCS EXPECTED TO DEVELOP ALONG BOUNDARY OVER IOWA...WITH
SOUTHERN FRINGES SLIDING THROUGH NORTHERN MO/WEST CENTRAL IL ON
MONDAY. LOWS SUNDAY NIGHT WILL BE IN THE LOW TO MID 70S WITH HIGHS
ON MONDAY IN THE UPPER 80S TO LOW 90S.
(MONDAY NIGHT THROUGH FRIDAY)
EXTENDED MODELS CONTINUE TO SLOW DOWN PASSAGE OF THIS COLD
FRONT...SO HOT AND HUMID CONDITIONS TO PERSIST THROUGH THURSDAY WITH
HIGHS EACH DAY IN THE UPPER 80S TO MID 90S. BY WEDNESDAY
NIGHT...COLD FRONT MOVES CLOSER TO AREA WITH CHANCES OF SHOWERS AND
THUNDERSTORMS FOR PORTIONS OF THE AREA WEDNESDAY NIGHT AND THURSDAY.
CONFIDENCE ON TIMING OF FRONTAL PASSAGE LOW...SO FOR NOW HAVE SILENT
SLIGHT CHANCE POPS IN FOR AREA THURSDAY NIGHT AND PORTIONS OF THE
AREA FRIDAY UNTIL FRONT FINALLY MOVES THROUGH. BY FRIDAY HIGHS WILL
BE IN THE MID TO UPPER 80S.
BYRD
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT)
ISSUED AT 1140 PM CDT FRI JUN 21 2013
NOT MUCH CHANGE FROM PREVIOUS TAF PACKAGE. MIDLEVEL ANTICYCLONE
REMAINS OVERHEAD STEERING ANY ORGANIZED CONVECTION WELL AWAY FROM
THE CWFA. LATEST NAM/GFS DOES TRY AND PAINT OUT SOME LIGHT
PRECIPITATION OVERNIGHT TONIGHT. HOWEVER...MODELS DID NOT SEEM TO
INITIALIZE CURRENT CONVECTION WELL. GIVEN THAT NOTE AND POSITION
BENEATH SYNOPTIC RIDGE...HAVE CONTINUED TO LEAVE OUT ANY MENTION
OF TS/SHRA. SCT HIGH-LEVEL CLOUDINESS WILL GIVE WAY TO MORE
DIURNAL CU WITH VFR BASES. AS FOR WINDS...SOUTHERLY WINDS WILL
CONTINUE THROUGH THE VALID TAF PERIOD AND PICK UP JUST A BIT
DURING THE DAY TOMORROW AROUND 10 KTS. BUFKIT SOUNDINGS DO NOT
SHOW MUCH IN THE WAY OF WINDS TO MIX DOWN TO SFC AT TOP OF
BOUNDARY LAYER UNLIKE THIS AFTERNOON...SO DO NOT HAVE ANY GUSTS MENTIONED.
SPECIFICS FOR KSTL...
NOT MUCH CHANGE FROM PREVIOUS TAF PACKAGE. MIDLEVEL ANTICYCLONE
REMAINS OVERHEAD STEERING ANY ORGANIZED CONVECTION WELL AWAY FROM
LAMBERT FIELD. LATEST NAM/GFS DOES TRY AND PAINT OUT SOME LIGHT
PRECIPITATION OVERNIGHT TONIGHT. HOWEVER...MODELS DID NOT SEEM TO
INITIALIZE CURRENT CONVECTION WELL. GIVEN THAT NOTE AND POSITION
BENEATH SYNOPTIC RIDGE...HAVE CONTINUED TO LEAVE OUT ANY MENTION
OF TS/SHRA. SCT HIGH-LEVEL CLOUDINESS WILL GIVE WAY TO MORE
DIURNAL CU WITH VFR BASES DURING THE DAY ON SATURDAY. AS FOR
WINDS...SOUTHERLY FLOW WILL CONTINUE THROUGH THE VALID TAF PERIOD
AND PICK UP JUST A BIT DURING THE DAY TOMORROW AROUND 10 KTS.
BUFKIT SOUNDINGS DO NOT SHOW MUCH IN THE WAY OF WINDS TO MIX DOWN
TO SFC AT TOP OF BOUNDARY LAYER UNLIKE THIS AFTERNOON...SO DID NOT
DENOTE ANY GUSTS.
GOSSELIN
&&
.LSX WATCHES/WARNINGS/ADVISORIES...
MO...NONE.
IL...NONE.
&&
$$
WFO LSX
AREA FORECAST DISCUSSION
NWS BILLINGS MT
321 AM MDT SAT JUN 22 2013
.SHORT TERM...VALID FOR TDY AND SUN...
WIDESPREAD SHOWERS AND STORMS ARE STILL EXPECTED ACROSS THE REGION
THIS AFTERNOON AND EVENING AS THE 500-HPA LOW NEAR BOISE AT 09 UTC
OPENS UP AND SWINGS ACROSS MT. LOCALLY HEAVY RAINFALL IS LIKELY.
FIRST OF ALL...WE WILL INCLUDE SOME PATCHY FOG IN THE FORECAST FOR
PLACES LIKE BAKER AND MILES CITY UNTIL 15 UTC. LOW TEMPERATURE-DEW
POINT SPREADS AS OF 09 UTC AND HRRR FORECASTS BOTH SUPPORT THAT.
TODAY...THE SCATTERED STORMS WHICH HAVE BEEN DEVELOPING OVER SOUTH
CENTRAL MT OVERNIGHT SHOULD LARGELY EXIT THE AREA BY 12 UTC AS THE
RIGHT ENTRANCE REGION OF THE 75+ KT 300-HPA JET STREAK WHICH SEEMS
RESPONSIBLE FOR THIS ACTIVITY HEADS NORTHEAST. MEANWHILE...FORCING
TIED TO THE 500-HPA TROUGH MAY BE A BIT DELAYED WHEN COMPARED WITH
EARLIER EXPECTATIONS. MOST 00 UTC GUIDANCE PICKED UP ON A BIT OF A
SLOW-DOWN WITH THIS SYSTEM...AND THAT LOOKS LIKE A GOOD SIMULATION
SINCE WE STILL HAVE A CLOSED LOW INSTEAD OF AN OPEN WAVE ACROSS ID
EARLY THIS MORNING. BASED ON THIS...WE DECIDED TO ADVERTISE MAINLY
CHANCE POPS ACROSS MUCH OF THE AREA FROM 12 TO 18 UTC...EXPECT OUT
AROUND LIVINGSTON WHERE FORCING MAY ARRIVE BY LATE MORNING. THE 00
UTC MULTI-MODEL CONSENSUS STILL SUPPORTS CATEGORICAL POPS FOR MOST
OF THE AREA THIS AFTERNOON WHEN STRONGER VERTICAL MOTION SHOWS UP.
PRECIPITABLE WATER VALUES OF 0.75 INCHES OR MORE CERTAINLY SUGGEST
LOCALLY HEAVY RAINFALL IS LIKELY. WHILE MID-LEVEL LAPSE RATES WILL
BE STEEP ENOUGH TO SUPPORT SOME THUNDER...SEVERE RISK WILL BE KEPT
IN CHECK BY A RELATIVELY COOL BOUNDARY LAYER AND RESULTANT LACK OF
CAPE. WE WILL BE WATCHING BURN SCAR AREAS CLOSELY...BUT THE THREAT
OF FLASH FLOODING WAS NOT SIGNIFICANT ENOUGH FOR A WATCH HEADLINE.
FINALLY...NOTE THAT SOME HIGH-ELEVATION SNOW IS LIKELY TODAY BASED
ON WET-BULB ZERO HEIGHTS WHICH SUGGEST A SNOW LEVEL PERHAPS AS LOW
AS 8700 FT MSL. THE BEARTOOTH HIGHWAY IS A GOOD CANDIDATE FOR SOME
SNOW.
TONIGHT...BASED ON THE MULTI-MODEL CONSENSUS...WE KEPT CATEGORICAL
POPS IN THE FORECAST UNTIL 06 UTC FROM HYSHAM AND SHERIDAN EAST TO
BAKER AND EKALAKA. LIKELY POPS ARE EVEN IN PLAY AT BILLINGS DURING
THE EVENING. BY THIS POINT IN TIME...DEEP MOIST CONVECTION WILL BE
ESTABLISHED OVER PARTS OF THE DAKOTAS AND NEBRASKA...AND THAT DOES
POSE THE RISK OF DISRUPTING MOISTURE ADVECTION INTO OUR AREA. EVEN
SO...THE EXPECTED QG-FORCING SHOULD STILL YIELD PRECIPITATION EAST
OF THE 500-HPA TROUGH AXIS. A DRYING TREND WILL BEGIN ACROSS SOUTH
CENTRAL MT OVERNIGHT AS THAT AXIS HEADS EASTWARD.
SUN...WE LINGERED SOME CHANCE POPS FROM MILES CITY TO BAKER DURING
THE MORNING IN RESPECT TO THE BIT SLOWER DEPARTURE OF THE MID- AND
UPPER-LEVEL TROUGH ADVERTISED BY MOST 00 UTC GUIDANCE. WE ACTUALLY
EVEN LEFT LOW POPS IN BAKER AFTER 18 UTC. HOWEVER...IN GENERAL THE
WHOLE AREA WILL HAVE A DRYING AND WARMING TREND AS FLOW ALOFT WILL
BECOME WESTERLY BY AFTERNOON. MIXING TO 700 HPA OR DEEPER BASED ON
FORECAST SOUNDINGS SUPPORTS HIGHS WELL INTO THE 70S F. SCHULTZ
.LONG TERM...VALID FOR MON...TUE...WED...THU...FRI...
EXTENDED FORECAST STARTS MONDAY AS THE FLOW OPENS UP TO THE
SOUTHWEST AGAIN. WEAK SHORTWAVES GET PULLED ACROSS THE AREA MONDAY
AFTERNOON BUT THE ATMOSPHERE IS PROGGED TO BE FAIRLY DRY SO WILL
KEEP POPS LOW. A STRONG SHORTWAVE IS PROGGED BY THE GFS TO SWING
ACROSS WESTERN ZONES MONDAY EVENING AND THIS SHOULD GENERATE
SCATTERED THUNDERSTORMS AS MOISTURE GETS PULLED IN WITH THIS
SYSTEM.
THE BEST CHANCE OF PRECIPITATION DURING THE EXTENDED PERIOD LOOKS
TO BE ON TUESDAY. HEIGHTS LOWER AS SEVERAL SHORTWAVES DRIFT ACROSS
WITH A STRONG WAVE EARLY IN THE DAY. TIMING OF THIS WAVE MAY BE
PROBLEMATIC AS IT MAY BE TOO EARLY TO TAP INTO THE STRONGEST
INSTABILITY. THAT BEING SAID...PRECIPITABLE WATERS RISE TO OVER
THREE QUARTERS OF AN INCH. LOW LEVEL FLOW DOES TURN WESTERLY AND
THIS MAY DRY OUT THE LOW LEVELS AND LIMIT PRECIP POTENTIAL. THAT
WILL NEED TO BE WATCHED. WILL KEEP SCATTERED POPS IN FOR NOW BUT
MAY NEED TO BE LOWERED IN THE FUTURE.
A STRONG UPPER RIDGE IS FORECAST TO BUILD WEDNESDAY THROUGH NEXT
WEEKEND. SUBTLE DIFFERENCES STARTING TO SHOW UP THOUGH AS THE
MODELS JUST NOW STARTED TO BUILD THE RIDGE A LITTLE FARTHER WEST
AND SET UP WEAK NORTHWEST FLOW OVER THE AREA. HEIGHTS WERE NOT
QUITE AS HIGH AS PREVIOUS RUNS EITHER. THIS WILL BE A TREND TO BE
WATCHED AS THE ECMWF HINTED AT THE SAME THING. DID RAISE FORECAST
HIGHS THROUGH THE END OF THE WEEK AS 700MB TEMPERATURES WERE A
LITTLE TOO WARM FOR INHERITED FORECAST HIGHS. TWH
&&
.AVIATION...
SHOWERS AND THUNDERSTORMS WILL DRIFT NORTH OF BILLINGS EARLY THIS
MORNING. THESE STORMS WILL HAVE HEAVY RAIN PRODUCING LOCAL MVFR
FLYING CONDITIONS. MORE SHOWERS AND THUNDERSTORMS WILL DEVELOP
OVER SOUTHERN SECTIONS BY LATE MORNING AND DRIFT NORTH TO
NORTHEAST THROUGH THE DAY. LOCAL MVFR CONDITIONS CAN BE EXPECTED
WITH HEAVY RAIN. THE MOSTLY LIKELY LOCATION FOR THE HEAVIEST RAIN
LOOKS TO BE EAST OF A BILLINGS TO SHERIDAN LINE...BUT CERTAINLY
SCATTERED STORMS WEST OF THIS LINE WILL CONTAIN HEAVY RAIN TOO.
THE SHOWERS WILL SHIFT OUT OF THE WEST THIS EVENING...CENTRAL
ZONES OVERNIGHT AND THE EAST EARLY SUNDAY. TWH
&&
.PRELIMINARY POINT TEMP/POPS...
TDY SUN MON TUE WED THU FRI
-------------------------------------------------------
BIL 068 051/078 054/086 062/086 058/085 059/087 058/089
9/T 61/B 11/B 23/T 31/B 10/U 00/U
LVM 065 041/079 046/083 054/081 053/083 052/085 053/085
8/T 51/B 13/T 34/T 31/B 11/U 11/U
HDN 070 049/078 052/087 059/088 057/087 059/088 059/090
9/T 61/B 11/B 22/T 21/B 11/U 10/U
MLS 073 055/079 056/088 062/088 060/087 059/087 060/087
8/T 83/T 11/B 22/T 21/B 10/U 01/U
4BQ 071 049/079 054/087 059/089 058/089 059/089 059/088
9/T 82/T 11/B 22/T 21/B 11/U 11/U
BHK 070 053/075 054/086 059/086 058/086 059/083 058/084
8/T 83/T 13/T 32/T 21/U 11/U 11/U
SHR 069 045/076 049/085 055/086 053/086 054/086 053/087
+/T 81/U 11/B 22/T 21/B 11/U 11/U
&&
.BYZ WATCHES/WARNINGS/ADVISORIES...
MT...NONE.
WY...NONE.
&&
$$
WEATHER.GOV/BILLINGS
AREA FORECAST DISCUSSION
NWS BURLINGTON VT
333 AM EDT SAT JUN 22 2013
.SYNOPSIS...
HIGH PRESSURE ANCHORED OFF THE ATLANTIC COAST WILL KEEP THE NORTH
COUNTRY DRY TODAY WITH PARTLY TO MOSTLY SUNNY SKIES THIS AFTERNOON
AND TEMPERATURES IN THE MID 70S TO LOWER 80S. A WARM FRONT WILL
MOVE SLOWLY THROUGH THE AREA ON SATURDAY WITH SOME SHOWERS AND A
SLIGHT CHANCE OF A THUNDERSTORM WITH TEMPERATURES AGAIN RANGING
THROUGH THE 70S NORTHEAST TO THE LOWER 80S SOUTHWEST. EVEN WARMER
AND MORE HUMID CONDITIONS ARE EXPECTED SUNDAY INTO NEXT WEEK...WITH
DAILY CHANCES FOR SHOWERS AND THUNDERSTORMS...MAINLY DURING THE
AFTERNOON AND EVENING HOURS.
&&
.NEAR TERM /UNTIL 6 AM THIS MORNING/...
AS OF 1250 AM EDT SATURDAY...INHERITED FORECAST IN GOOD SHAPE
WITH ONLY UPDATE NEEDED TO INCREASE SKY COVER AS CONVECTIVE DEBRIS
CLOUDS ARE FILLING INTO THE REGION. WITH INCREASED CLOUD COVER
TEMPS SHOULD HOLD FAIRLY STEADY FOR THE REMAINDER OF THE NIGHT IN
THE 50S.
&&
.SHORT TERM /6 AM THIS MORNING THROUGH MONDAY/...
AS OF 323 PM EDT FRIDAY...SATURDAY...MODERATE CONFIDENCE CONTINUES
THAT WE`LL SEE SOME SOME SHOWERS AND A SLIGHT CHANCE OF A
THUNDERSTORM AS THE DECAYING MCV AND SHORT WAVE TROF MOVES ACROSS
THE REGION DURING MIDDAY INTO THE EARLY EVENING. MODEL GUIDANCE
HAS BEEN STRUGGLING WITH THE PLACEMENT OF THIS FEATURE WITH THE
GFS MORE WIDESPREAD AND FURTHER SOUTH AND THE NAM FURTHER NORTH.
HAVE PLAYED IT MORE TOWARD THE GFS/MAV SOLUTION AS RAP ANALYSIS
SHOWS SIGNIFICANT MCV HAS FORMED. SO HIGHER POPS THAN WHAT THE NAM
MOS SUGGESTS AND SLIGHT COOLER TEMPERATURES. HAVE STAYED MAINLY
NEAR 80 WITH COOLER TEMPS NORTHEAST AND WARMER SOUTHWEST. WHERE
CLOUDS/SHOWERS HANG ON IT COULD BE 5 DEGREES COOLER AND WHERE THEY
DISSIPATE 5 DEGREES WARMER.
IN THE ABSENCE OF ANY LARGE SCALE FORCING...ANY CONVECTIVE
ACTIVITY WILL DISSIPATE GOING INTO THE EVENING AND OVERNIGHT
HOURS SAT NIGHT WITH LOWS MAINLY IN THE 60S.
ON SUNDAY...MORE TYPICAL ISOLATED TO SCATTERED AIRMASS TYPE PULSE
SHOWERS AND THUNDERSTORMS WILL BE POSSIBLE AGAIN ON SUNDAY MAINLY
IN THE MID TO LATE AFTERNOON/EVENING WITH ACTIVITY SETTLING DOWN
OVERNIGHT SUNDAY NIGHT. CAPE VALUES NOT ALL THAT IMPRESSIVE (BELOW
100 J/KG) WITH GFS SUGGESTING A CAPPING SUBSIDENCE INVERSION MAY
BE IN PLACE SO KEPT A MINIMAL CHANCE POPS IN THE FORECAST. IT
SHOULD BE CONSIDERABLY WARMER AND MORE HUMID AIR PUSHES IN AS THE
WARM FRONT LIFTS NORTHEAST SUNDAY WITH HIGHS IN THE 80S.
SUNDAY NIGHT SHOULD BE VERY MILD WITH READINGS IN THE 60S PERHAPS NEAR 70
AT BTV WITH WARM AND HUMID AIR FIRMLY ENTRENCHED.
&&
.LONG TERM /MONDAY NIGHT THROUGH FRIDAY/...
AS OF 333 AM EDT SATURDAY...FOR THE EXTENDED PERIOD...BROAD UPPER
RIDGE ACROSS THE SOUTHERN HALF OF THE COUNTRY COMBINED WITH STRONG
SFC RIDGE OFFSHORE WILL ALLOW FOR WARM TEMPS ACROSS THE AREA THRU
THE PERIOD. ACCOMPANYING THESE EXPECTED TEMPS WILL ALSO BE THE
CHANCE FOR RW/TRW. MDLS CONTINUE TO SHOW ZONAL FLOW OVER THE
NORTHERN PORTION OF THE COUNTRY AS A RESULT OF UPPER RIDGE TO THE
SOUTH. 850/925 TEMPS RANGING FROM +16C TO +20C WILL BRING DAYTIME
HIGHS WELL INTO THE 80S W/ SOME LOCAL 90F...ESPECIALLY FOR FIRST
HALF OF EXTENDED. THE LATTER PORTION WILL TAPER DOWN TO NEAR 80F
AS BROAD TROUGH WORKING OUT OF THE GREAT LKS REGION BREAKS DOWN
UPPER RIDGE...ALLOWING FOR INCR CHANCES FOR CLDS/MOISTURE W/ BROAD
SW FLOW SETTING UP. OVERNGT LOWS IN THE 50S TO M60S. OVERALL FOR
PRECIP...STILL EXPECTING SCT RW/TRW THRU WEDNESDAY AS WK
SHORTWAVES WORK ALONG NORTHERN FRINGE OF UPPER RIDGE...FOLLOWED BY
MORE AREAL COVERAGE IN TRW/RW AS LOW FROM GREAT LKS APPROACHES.
SOME MDL DIFFERENCES FOR TIMING/PLACEMENT OF TROUGH FOR
THURS/FRI...SO WILL KEEP OVERALL CHANCE POPS IN ATTM. W/ AIRMASS
ON THE HUMID SIDE THRU PERIOD...HIGH PW CONTENT OF NEAR 1.50" WILL
CREATE THE POTENTIAL FOR SOME HEAVY DOWNPOURS IN ANY TRW THAT DOES
DEVELOP...ESPECIALLY THURS/FRI.
&&
.AVIATION /08Z SATURDAY THROUGH WEDNESDAY/...
THROUGH 06Z SUNDAY...VFR COND THRU MUCH OF FORECAST PERIOD. EXPECTING
MID CLD COVER AROUND BKN100-150 TO TRANSLATE DOWN TO BKN035-080
THIS AFTNOON AS WX SYSTEM APPROACHES. MSS/SLK WILL SEE MVFR COND
WITH CEILINGS DOWN NEAR BKN030 AND -RW DRIVING DOWN TO 5-6SM AT
TIMES BY 00Z SUN. AFT MIDDAY...VCSH/-SHRA POSSIBLE FOR ALL AREAS.
WINDS GENERALLY RANGING FROM SE TO SW 5-10KTS.
OUTLOOK 06Z SUNDAY THROUGH WEDNESDAY... MAINLY VFR CONDITIONS WL
PREVAIL THRU THE TIME PERIOD WITH THE EXCEPTION OF BRIEF MVFR/IFR
IN THE HEAVIER SHOWERS/STORMS. BEST CHCS FOR STORMS WL BE DURING
THE AFTERNOON AND EARLY EVENING HRS THRU TUESDAY. IN
ADDITION...SOME PATCHY EARLY MORNING FOG/BR WITH MVFR/IFR WL BE
POSSIBLE IF ANY TAF SITE RECIEVES HEAVY RAINFALL FROM CONVECTION
DURING THE DAYTIME. EXPECT MAINLY SOUTHERLY WINDS THRU THE PERIOD.
&&
.EQUIPMENT...
OBSERVATIONS FROM RUTLAND-SOUTHERN VERMONT REGIONAL AIRPORT
(KRUT) REMAIN UNAVAILABLE DUE TO A TELEPHONE COMMS LINE ISSUE. THE
FAA AOCC IS AWARE OF THE ISSUE...BUT THERE IS NO ESTIMATE AVAILABLE
AT THIS TIME AS TO WHEN THIS COMMS OUTAGE WILL BE FIXED.
&&
.BTV WATCHES/WARNINGS/ADVISORIES...
VT...NONE.
NY...NONE.
&&
$$
SYNOPSIS...SISSON
NEAR TERM...LAHIFF
SHORT TERM...SISSON
LONG TERM...JN
AVIATION...JN/LOCONTO
EQUIPMENT...
AREA FORECAST DISCUSSION
NWS BURLINGTON VT
135 AM EDT SAT JUN 22 2013
.SYNOPSIS...
HIGH PRESSURE ANCHORED OFF THE ATLANTIC COAST WILL KEEP THE NORTH
COUNTRY DRY TODAY WITH PARTLY TO MOSTLY SUNNY SKIES THIS AFTERNOON
AND TEMPERATURES IN THE MID 70S TO LOWER 80S. A WARM FRONT WILL
MOVE SLOWLY THROUGH THE AREA ON SATURDAY WITH SOME SHOWERS AND A
SLIGHT CHANCE OF A THUNDERSTORM WITH TEMPERATURES AGAIN RANGING
THROUGH THE 70S NORTHEAST TO THE LOWER 80S SOUTHWEST. EVEN WARMER
AND MORE HUMID CONDITIONS ARE EXPECTED SUNDAY INTO NEXT WEEK...WITH
DAILY CHANCES FOR SHOWERS AND THUNDERSTORMS...MAINLY DURING THE
AFTERNOON AND EVENING HOURS.
&&
.NEAR TERM /UNTIL 6 AM THIS MORNING/...
AS OF 1250 AM EDT SATURDAY...INHERITED FORECAST IN GOOD SHAPE
WITH ONLY UPDATE NEEDED TO INCREASE SKY COVER AS CONVECTIVE DEBRIS
CLOUDS ARE FILLING INTO THE REGION. WITH INCREASED CLOUD COVER
TEMPS SHOULD HOLD FAIRLY STEADY FOR THE REMAINDER OF THE NIGHT IN
THE 50S.
&&
.SHORT TERM /6 AM THIS MORNING THROUGH SUNDAY NIGHT/...
AS OF 323 PM EDT FRIDAY...SATURDAY...MODERATE CONFIDENCE CONTINUES
THAT WE`LL SEE SOME SOME SHOWERS AND A SLIGHT CHANCE OF A
THUNDERSTORM AS THE DECAYING MCV AND SHORT WAVE TROF MOVES ACROSS
THE REGION DURING MIDDAY INTO THE EARLY EVENING. MODEL GUIDANCE
HAS BEEN STRUGGLING WITH THE PLACEMENT OF THIS FEATURE WITH THE
GFS MORE WIDESPREAD AND FURTHER SOUTH AND THE NAM FURTHER NORTH.
HAVE PLAYED IT MORE TOWARD THE GFS/MAV SOLUTION AS RAP ANALYSIS
SHOWS SIGNIFICANT MCV HAS FORMED. SO HIGHER POPS THAN WHAT THE NAM
MOS SUGGESTS AND SLIGHT COOLER TEMPERATURES. HAVE STAYED MAINLY
NEAR 80 WITH COOLER TEMPS NORTHEAST AND WARMER SOUTHWEST. WHERE
CLOUDS/SHOWERS HANG ON IT COULD BE 5 DEGREES COOLER AND WHERE THEY
DISSIPATE 5 DEGREES WARMER.
IN THE ABSENCE OF ANY LARGE SCALE FORCING...ANY CONVECTIVE
ACTIVITY WILL DISSIPATE GOING INTO THE EVENING AND OVERNIGHT
HOURS SAT NIGHT WITH LOWS MAINLY IN THE 60S.
ON SUNDAY...MORE TYPICAL ISOLATED TO SCATTERED AIRMASS TYPE PULSE
SHOWERS AND THUNDERSTORMS WILL BE POSSIBLE AGAIN ON SUNDAY MAINLY
IN THE MID TO LATE AFTERNOON/EVENING WITH ACTIVITY SETTLING DOWN
OVERNIGHT SUNDAY NIGHT. CAPE VALUES NOT ALL THAT IMPRESSIVE (BELOW
100 J/KG) WITH GFS SUGGESTING A CAPPING SUBSIDENCE INVERSION MAY
BE IN PLACE SO KEPT A MINIMAL CHANCE POPS IN THE FORECAST. IT
SHOULD BE CONSIDERABLY WARMER AND MORE HUMID AIR PUSHES IN AS THE
WARM FRONT LIFTS NORTHEAST SUNDAY WITH HIGHS IN THE 80S.
SUNDAY NIGHT SHOULD BE VERY MILD WITH READINGS IN THE 60S PERHAPS NEAR 70
AT BTV WITH WARM AND HUMID AIR FIRMLY ENTRENCHED.
&&
.LONG TERM /MONDAY THROUGH FRIDAY/...
AS OF 350 PM EDT FRIDAY...LARGE SCALE PATTERN WL CONTINUE TO
SUPPORT MID/UPPER LVL RIDGE ACRS THE SE CONUS WITH FAST WESTERLY
FLW ALOFT NEAR THE INTERNATIONAL BORDER THRU EARLY NEXT WEEK. BY
MID TO LATE NEXT WEEK ALL GUIDANCE SUGGESTS A PATTERN CHANGE WITH
DEVELOPMENT OF FULL LATITUDE TROF ACRS THE GREAT LAKES/EASTERN
CONUS AND LARGE RIDGE OVER THE INTER-MOUNTAIN WEST. THIS WL RESULT
IN MUCH ABOVE NORMAL TEMPS FOR MONDAY/TUESDAY WITH CHCS FOR
AFTN/EVENING SHOWERS/STORMS...WITH A TREND TWD COOLER AND WETTER
CONDITIONS BY LATE NEXT WEEK...AS TROF DEVELOPS AND SFC LOW PRES
IMPACTS OUR FA. PROGGED 85H TEMPS NEAR 16C AND 925MB TEMPS BTWN
20-22C ON MONDAY/TUESDAY...SUPPORTS HIGHS WELL INTO THE 80S WITH
EVEN A FEW LOWER 90S POSSIBLE IN THE WARMER VALLEY LOCATIONS. IN
ADDITION...PROGGED SFC DWPTS ARE EXPECTED TO BE IN THE MID/UPPER
60S...CREATING VERY MUGGY CONDITIONS...ESPECIALLY ON MONDAY. THIS
HEAT/HUMIDITY WL HELP TO PRODUCE SOME MODEST CAPE
VALUES...COMBINED WITH EMBEDDED 5H VORTS WL HELP IN THE
DEVELOPMENT OF AFTN/EVENING SHOWERS/STORMS. WL CONT TO MENTION CHC
POPS ATTM...WITH MAIN FOCUS DURING THE PEAK HEATING HRS. ANY
STORMS THAT DUE DEVELOP WL HAVE THE POTENTIAL TO PRODUCE LOCALIZED
HEAVY DOWNPOURS WITH PW VALUES BTWN 1.50 AND 1.75". BETTER
DYNAMICS AND MOISTURE ARRIVES BY LATE NEXT WK...AS MID/UPPER LVL
TROF DEVELOPS OVER THE GREAT LAKES. STILL SOME UNCERTAINTY OF
MAGNITUDE AND POSITION OF SYSTEM ALONG WITH AVAILABLE
MOISTURE...THEREFORE WL MENTION CHC POPS ATTM...WITH TEMPS
DROPPING BACK TO NEAR NORMAL. EXPECT ABOVE NORMAL LOW TEMPS THRU
THE PERIOD...GIVEN AMOUNT OF BL MOISTURE AND POTENTIAL FOR
CLOUDS/PRECIP...MAINLY IN THE U50S MTNS TO NEAR 70F CPV/SLV.
&&
.AVIATION /06Z SATURDAY THROUGH WEDNESDAY/...
THROUGH 06Z SUNDAY...VFR COND THRU MUCH OF FORECAST PERIOD. EXPECTING
MID CLD COVER AROUND BKN100-150 TO TRANSLATE DOWN TO BKN035-080
THIS AFTNOON AS WX SYSTEM APPROACHES. MSS/SLK WILL SEE MVFR COND
WITH CEILINGS DOWN NEAR BKN030 AND -RW DRIVING DOWN TO 5-6SM AT
TIMES BY 00Z SUN. AFT MIDDAY...VCSH/-SHRA POSSIBLE FOR ALL AREAS.
WINDS GENERALLY RANGING FROM SE TO SW 5-10KTS.
OUTLOOK 06Z SUNDAY THROUGH WEDNESDAY... MAINLY VFR CONDITIONS WL
PREVAIL THRU THE TIME PERIOD WITH THE EXCEPTION OF BRIEF MVFR/IFR
IN THE HEAVIER SHOWERS/STORMS. BEST CHCS FOR STORMS WL BE DURING
THE AFTERNOON AND EARLY EVENING HRS THRU TUESDAY. IN
ADDITION...SOME PATCHY EARLY MORNING FOG/BR WITH MVFR/IFR WL BE
POSSIBLE IF ANY TAF SITE RECIEVES HEAVY RAINFALL FROM CONVECTION
DURING THE DAYTIME. EXPECT MAINLY SOUTHERLY WINDS THRU THE PERIOD.
&&
.EQUIPMENT...
OBSERVATIONS FROM RUTLAND-SOUTHERN VERMONT REGIONAL AIRPORT
(KRUT) REMAIN UNAVAILABLE DUE TO A TELEPHONE COMMS LINE ISSUE. THE
FAA AOCC IS AWARE OF THE ISSUE...BUT THERE IS NO ESTIMATE AVAILABLE
AT THIS TIME AS TO WHEN THIS COMMS OUTAGE WILL BE FIXED.
&&
.BTV WATCHES/WARNINGS/ADVISORIES...
VT...NONE.
NY...NONE.
&&
$$
SYNOPSIS...SISSON
NEAR TERM...LAHIFF
SHORT TERM...SISSON
LONG TERM...TABER
AVIATION...JN/LOCONTO
EQUIPMENT...BTV
AREA FORECAST DISCUSSION
NWS BURLINGTON VT
1252 AM EDT SAT JUN 22 2013
.SYNOPSIS...
HIGH PRESSURE ANCHORED OFF THE ATLANTIC COAST WILL KEEP THE NORTH
COUNTRY DRY TODAY WITH PARTLY TO MOSTLY SUNNY SKIES THIS AFTERNOON
AND TEMPERATURES IN THE MID 70S TO LOWER 80S. A WARM FRONT WILL
MOVE SLOWLY THROUGH THE AREA ON SATURDAY WITH SOME SHOWERS AND A
SLIGHT CHANCE OF A THUNDERSTORM WITH TEMPERATURES AGAIN RANGING
THROUGH THE 70S NORTHEAST TO THE LOWER 80S SOUTHWEST. EVEN WARMER
AND MORE HUMID CONDITIONS ARE EXPECTED SUNDAY INTO NEXT WEEK...WITH
DAILY CHANCES FOR SHOWERS AND THUNDERSTORMS...MAINLY DURING THE
AFTERNOON AND EVENING HOURS.
&&
.NEAR TERM /UNTIL 6 AM THIS MORNING/...
AS OF 1250 AM EDT SATURDAY...INHERITED FORECAST IN GOOD SHAPE
WITH ONLY UPDATE NEEDED TO INCREASE SKY COVER AS CONVECTIVE DEBRIS
CLOUDS ARE FILLING INTO THE REGION. WITH INCREASED CLOUD COVER
TEMPS SHOULD HOLD FAIRLY STEADY FOR THE REMAINDER OF THE NIGHT IN
THE 50S.
&&
.SHORT TERM /6 AM THIS MORNING THROUGH SUNDAY NIGHT/...
AS OF 323 PM EDT FRIDAY...SATURDAY...MODERATE CONFIDENCE CONTINUES
THAT WE`LL SEE SOME SOME SHOWERS AND A SLIGHT CHANCE OF A
THUNDERSTORM AS THE DECAYING MCV AND SHORT WAVE TROF MOVES ACROSS
THE REGION DURING MIDDAY INTO THE EARLY EVENING. MODEL GUIDANCE
HAS BEEN STRUGGLING WITH THE PLACEMENT OF THIS FEATURE WITH THE
GFS MORE WIDESPREAD AND FURTHER SOUTH AND THE NAM FURTHER NORTH.
HAVE PLAYED IT MORE TOWARD THE GFS/MAV SOLUTION AS RAP ANALYSIS
SHOWS SIGNIFICANT MCV HAS FORMED. SO HIGHER POPS THAN WHAT THE NAM
MOS SUGGESTS AND SLIGHT COOLER TEMPERATURES. HAVE STAYED MAINLY
NEAR 80 WITH COOLER TEMPS NORTHEAST AND WARMER SOUTHWEST. WHERE
CLOUDS/SHOWERS HANG ON IT COULD BE 5 DEGREES COOLER AND WHERE THEY
DISSIPATE 5 DEGREES WARMER.
IN THE ABSENCE OF ANY LARGE SCALE FORCING...ANY CONVECTIVE
ACTIVITY WILL DISSIPATE GOING INTO THE EVENING AND OVERNIGHT
HOURS SAT NIGHT WITH LOWS MAINLY IN THE 60S.
ON SUNDAY...MORE TYPICAL ISOLATED TO SCATTERED AIRMASS TYPE PULSE
SHOWERS AND THUNDERSTORMS WILL BE POSSIBLE AGAIN ON SUNDAY MAINLY
IN THE MID TO LATE AFTERNOON/EVENING WITH ACTIVITY SETTLING DOWN
OVERNIGHT SUNDAY NIGHT. CAPE VALUES NOT ALL THAT IMPRESSIVE (BELOW
100 J/KG) WITH GFS SUGGESTING A CAPPING SUBSIDENCE INVERSION MAY
BE IN PLACE SO KEPT A MINIMAL CHANCE POPS IN THE FORECAST. IT
SHOULD BE CONSIDERABLY WARMER AND MORE HUMID AIR PUSHES IN AS THE
WARM FRONT LIFTS NORTHEAST SUNDAY WITH HIGHS IN THE 80S.
SUNDAY NIGHT SHOULD BE VERY MILD WITH READINGS IN THE 60S PERHAPS NEAR 70
AT BTV WITH WARM AND HUMID AIR FIRMLY ENTRENCHED.
&&
.LONG TERM /MONDAY THROUGH FRIDAY/...
AS OF 350 PM EDT FRIDAY...LARGE SCALE PATTERN WL CONTINUE TO
SUPPORT MID/UPPER LVL RIDGE ACRS THE SE CONUS WITH FAST WESTERLY
FLW ALOFT NEAR THE INTERNATIONAL BORDER THRU EARLY NEXT WEEK. BY
MID TO LATE NEXT WEEK ALL GUIDANCE SUGGESTS A PATTERN CHANGE WITH
DEVELOPMENT OF FULL LATITUDE TROF ACRS THE GREAT LAKES/EASTERN
CONUS AND LARGE RIDGE OVER THE INTER-MOUNTAIN WEST. THIS WL RESULT
IN MUCH ABOVE NORMAL TEMPS FOR MONDAY/TUESDAY WITH CHCS FOR
AFTN/EVENING SHOWERS/STORMS...WITH A TREND TWD COOLER AND WETTER
CONDITIONS BY LATE NEXT WEEK...AS TROF DEVELOPS AND SFC LOW PRES
IMPACTS OUR FA. PROGGED 85H TEMPS NEAR 16C AND 925MB TEMPS BTWN
20-22C ON MONDAY/TUESDAY...SUPPORTS HIGHS WELL INTO THE 80S WITH
EVEN A FEW LOWER 90S POSSIBLE IN THE WARMER VALLEY LOCATIONS. IN
ADDITION...PROGGED SFC DWPTS ARE EXPECTED TO BE IN THE MID/UPPER
60S...CREATING VERY MUGGY CONDITIONS...ESPECIALLY ON MONDAY. THIS
HEAT/HUMIDITY WL HELP TO PRODUCE SOME MODEST CAPE
VALUES...COMBINED WITH EMBEDDED 5H VORTS WL HELP IN THE
DEVELOPMENT OF AFTN/EVENING SHOWERS/STORMS. WL CONT TO MENTION CHC
POPS ATTM...WITH MAIN FOCUS DURING THE PEAK HEATING HRS. ANY
STORMS THAT DUE DEVELOP WL HAVE THE POTENTIAL TO PRODUCE LOCALIZED
HEAVY DOWNPOURS WITH PW VALUES BTWN 1.50 AND 1.75". BETTER
DYNAMICS AND MOISTURE ARRIVES BY LATE NEXT WK...AS MID/UPPER LVL
TROF DEVELOPS OVER THE GREAT LAKES. STILL SOME UNCERTAINTY OF
MAGNITUDE AND POSITION OF SYSTEM ALONG WITH AVAILABLE
MOISTURE...THEREFORE WL MENTION CHC POPS ATTM...WITH TEMPS
DROPPING BACK TO NEAR NORMAL. EXPECT ABOVE NORMAL LOW TEMPS THRU
THE PERIOD...GIVEN AMOUNT OF BL MOISTURE AND POTENTIAL FOR
CLOUDS/PRECIP...MAINLY IN THE U50S MTNS TO NEAR 70F CPV/SLV.
&&
.AVIATION /06Z SATURDAY THROUGH WEDNESDAY/...
THROUGH 00Z SUNDAY...MAINLY VFR THROUGH THE OVERNIGHT HOURS
THOUGH MID TO HIGH-LEVEL CLOUDINESS WILL BE ON THE INCREASE
PARTICULARLY AFTER MIDNIGHT. WINDS WILL BE LIGHT AND VARIABLE
UNDER BROAD SFC RIDGING. FOR SATURDAY...EXPECTING SHOWERS AND
THUNDERSTORMS AND DEVELOPING SOUTHEASTWARD WITH TIME. EXACT TIMING
ON THE ONSET OF PRECIPITATION IS DIFFICULT IT IS DEPENDENT ON WHAT
EVOLVES WITH THE ONGOING CONVECTION ACROSS THE NORTHERN
PLAINS/GREAT LAKES REGION TONIGHT. HOWEVER BASED ON PRESENT
INDICATIONS THIS APPEARS TO BE IN THE 13-18Z TIMEFRAME. FOR NOW
HAVE TREATED WITH VCSH DURING THAT PERIOD OF TIME. POTENTIAL FOR
MVFR VISIBILITIES (BRIEF IFR VISIBILITIES POSSIBLE IN
STEADIER/HEAVIER RAIN). WINDS WILL BE SOUTH/SOUTHWEST UNDER
10KTS...EXCEPT LIGHT/VARIABLE AT MSS.
OUTLOOK 00Z SUNDAY THROUGH TUESDAY... MAINLY VFR CONDITIONS WL PREVAIL
THRU THE TIME PERIOD WITH THE EXCEPTION OF BRIEF MVFR/IFR IN THE
HEAVIER SHOWERS/STORMS. BEST CHCS FOR STORMS WL BE DURING THE
AFTERNOON AND EARLY EVENING HRS THRU TUESDAY. IN ADDITION...SOME
PATCHY EARLY MORNING FOG/BR WITH MVFR/IFR WL BE POSSIBLE IF ANY
TAF SITE RECIEVES HEAVY RAINFALL FROM CONVECTION DURING THE
DAYTIME. EXPECT MAINLY SOUTHERLY WINDS THRU THE PERIOD.
&&
.EQUIPMENT...
OBSERVATIONS FROM RUTLAND-SOUTHERN VERMONT REGIONAL AIRPORT
(KRUT) REMAIN UNAVAILABLE DUE TO A TELEPHONE COMMS LINE ISSUE. THE
FAA AOCC IS AWARE OF THE ISSUE...BUT THERE IS NO ESTIMATE AVAILABLE
AT THIS TIME AS TO WHEN THIS COMMS OUTAGE WILL BE FIXED.
&&
.BTV WATCHES/WARNINGS/ADVISORIES...
VT...NONE.
NY...NONE.
&&
$$
SYNOPSIS...SISSON
NEAR TERM...LAHIFF
SHORT TERM...SISSON
LONG TERM...TABER
AVIATION...TABER/LOCONTO
EQUIPMENT...
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
145 AM EDT SAT JUN 22 2013
.SYNOPSIS...
A SLOW-MOVING FRONT JUST OFFSHORE...WILL DRIFT WEST AND ONSHORE LATE
TONIGHT AND SATURDAY...INCREASING THE POTENTIAL FOR SHOWERS AND
THUNDERSTORMS. TYPICAL SUMMERTIME WEATHER IS EXPECTED TO RETURN NEXT
WEEK WITH BERMUDA HIGH PRESSURE...THE PIEDMONT TROUGH AND THE DAILY
SEA BREEZE...BECOMING THE DOMINANT SURFACE FEATURES.
&&
.NEAR TERM /UNTIL 6 AM SATURDAY MORNING/...
AS OF 1045 PM FRIDAY...AS WE MOVE FURTHER INTO THE PRE-DAWN
SATURDAY HOURS...CONVECTION ALONG AND AHEAD OF THE COASTAL FRONT
JUST OFFSHORE...WILL OVERSPREAD THE COASTAL AREAS OF THE ILM CWA.
AS SEEN WITH LOCAL AND ADJACENT 88DS...THE CONVECTION FALLS APART
THE FURTHER INLAND IT TRACKS DUE TO THE DRIER AIR MASS IT
ENCOUNTERS. WITH TIME AND AFTER THIS PERIOD...THE AIRMASS OVER
INLAND LOCATIONS WILL BECOME SATURATED AND PRIMED FOR EXTENDED
CONVECTION. TIMING ISSUES CONTINUE FOR THE SPREADING INLAND OF
THE 50-70 POPS OVERNIGHT INTO SATURDAY. LATEST SREF PROBS FOR
MEASURE-ABLE PCPN ILLUSTRATES DRAMATICALLY INCREASING POPS TOWARD
DAYBREAK ACROSS THE MAJORITY OF THE ILM CWA. MIN TEMP GUIDANCE
EARLIER TWEAKED WILL REMAIN AS IS. THE KLTX VWP AND 00Z SOUNDINGS
FROM CHS AND MHX INDICATE AN ONSHORE FLOW SFC THRU AT LEAST 20K
FEET...INDICATIVE OF A SUBTROPICAL/TROPICAL AIR MASS BEING
ADVECTED ACROSS THE FA. 00Z PWS HAVE ALSO INCREASED...UP TO 1.87
INCHES AT MHX AND 1.68 INCHES AT CHS. PWS WILL LIKELY FURTHER RISE
OVERNIGHT...AND THUS WILL CONTINUE TO HIGHLIGHT PONDING OF WATER
POSSIBLE FROM HEAVY DOWNPOURS TONIGHT INTO SATURDAY IN THE HWO.
&&
.SHORT TERM /6 AM SATURDAY MORNING THROUGH SUNDAY NIGHT/...
AS OF 3 PM FRIDAY...THE MAIN FORECAST CHALLENGE WILL BE CENTERED
AROUND POPS MAINLY FOR SATURDAY AS A SEEMINGLY EVER PRESENT FRONT
FINALLY MAKES A MOVE INLAND. I HAVE TRENDED TOWARD THE MORE
AGGRESSIVE MET/NAM GUIDANCE FOR POPS WHICH WARRANT AN INCREASE FOR
SATURDAY`S VALUES. THIS CALLS FOR AN INCREASE IN CLOUD COVER AS
WELL WHILE LEANING TOWARD THE LOWER NUMBERS ALONG THE COAST FOR
HIGHS. AS FOR SATURDAY NIGHT AND SUNDAY THE FRONT WILL BECOME
ABSORBED INTO THE SOUTHERLY SYNOPTIC FLOW AND POPS WILL BE
ADDRESSED ON A MORE TYPICAL FASHION OF HIGHER VALUES BEING IN THE
AFTERNOON AND EARLY EVENING HOURS.
&&
.LONG TERM /MONDAY THROUGH FRIDAY/...
AS OF 3 PM FRIDAY...UPPER LEVEL HIGH PRESSURE JUST OFF THE
CAROLINA COAST MONDAY AND TUESDAY. THERE MAY BE A WEAKNESS ON ITS
WESTERN PERIPHERY DUE TO LEFTOVER REMNANTS OF THE UPPER LOW OVER
THE WRN PART OF THE CAROLINAS CURRENTLY. AT THE SURFACE HIGH
PRESSURE TO COVER A BROAD EXPANSE OF THE WEST ATLANTIC. THE
ORIENTATION OF THE HIGH WILL BE WEST TO EAST ELONGATED...WHICH IS
NOT OPTIMAL FOR MOISTURE ADVECTION INTO THE REGION. EVEN SO A
FAIRLY SEASONABLE AND DIURNAL COVERAGE OF CONVECTION SEEMS LIKELY.
WED AND THURS TRANSITIONAL DAYS ALOFT WITH RIDGING BECOMING BROAD
ACROSS THE NATIONS MIDSECTION EARLY ON FOLLOWED BY LARGE INCREASE
IN AMPLITUDE OVER WRN STATES ON THURSDAY. THE TROUGHINESS
DOWNSTREAM OVER THE EAST WILL BE CLOSED OFF QUICKLY PREVENTING
MUCH AMPLITUDE INCREASE/LOCAL EFFECTS. INSTEAD A BROAD AND WEAK
NORTHWESTERLY FLOW DEVELOPS. SURFACE PIEDMONT TROUGHINESS DEVELOPS
AS WELL. IN THE END THE FORMER MAY ACT TO SLIGHTLY INHIBIT
CONVECTION WHILE THE LATTER TRIES TO INCREASE IT. END RESULT MAY
MEAN LITTLE SIGNIFICANT CHANGES IN RAIN CHANCES THROUGH MOST OF
THE PERIOD. ON FRIDAY TROUGHINESS APPEARS TO INCREASE IN AMPLITUDE
OVER THE EASTERN U.S.
&&
.AVIATION /06Z SATURDAY THROUGH WEDNESDAY/...
AS OF 06Z...PERIODS OF MVFR/IFR EXPECTED DUE TO ISOLATED TO
SCATTERED SHOWERS/THUNDERSTORMS...PERIODS OF LOWERED CIGS AND PATCHY
FOG THROUGH THE VALID PERIOD. OTHERWISE VFR.
TRICKY FORECAST CONTINUES FOR THE TAF PERIOD AS A NEARLY STALLED
FRONT OFFSHORE CONTINUES TO SLOWLY MOVE WEST TOWARD THE AREA.
LATEST RADAR IMAGERY DEPICTS SHOWERS AFFECTING MAINLY THE COASTAL
SITES. ANTICIPATE TREND WILL CONTINUE THROUGH THE VALID PERIOD...
WITH HEAVIER RAINFALL EXPECTED TO PUSH TO THE INLAND SITES BY THE
MORNING HOURS. PERIODS OF HEAVY RAINFALL...ALONG WITH INTERMITTENT
PERIODS OF LOWERED CIGS...ARE EXPECTED TO REDUCE CONDITIONS TO
MVFR/IFR THROUGHOUT THE VALID PERIOD. THUNDERSTORM CHANCES WILL
INCREASE ON SATURDAY AS WELL...THOUGH GIVEN UNCERTAINTY HAVE OPTED
TO KEEP VCTS ATTM. AS FOR WINDS...NORTHEAST WINDS 5 TO 8 KTS THROUGH
LATE MORNING ON SATURDAY WILL GRADUALLY BECOME EAST-SOUTHEAST ALONG
THE COAST BY AFTERNOON WITH SUSTAINED WINDS AOB 8 KTS. INTO THE
EVENING HOURS...TSRA CHANCES WILL DIMINISH WITH ISOLATED TO
SCATTERED SHOWERS CONTINUING AND LIGHT EAST-SOUTHEAST WINDS.
EXTENDED OUTLOOK...ISOLATED TO SCATTERED SHOWERS THROUGH WEDNESDAY
AS A STALLED FRONT LINGERS NEAR THE COAST. BETTER CHANCE OF
PRECIPITATION WILL BE IN THE AFTERNOON HOURS WITH LOCALIZED PERIODS
OF MVFR/IFR POSSIBLE.
&&
.MARINE...
NEAR TERM /THROUGH TONIGHT/...
AS OF 1045 PM FRIDAY...THE APPROACH AND EVENTUAL PASSAGE OF THE
COASTAL FRONT ONSHORE WILL GOVERN THE WINDS ACROSS THE ILM WATERS.
LOOKING AT A NE-E WIND AHEAD OF THE FRONT...SE-S WIND AFTER ITS
PASSAGE. SFC PG HAVING SOMEWHAT RELAXED AHEAD OF THE FRONT...
RESULTING WITH WIND SPEEDS AROUND 10 KT. HRRR AND NAM INDICATE A
TIGHTENING OF THE GRADIENT AFTER ITS PASSAGE...WITH WIND SPEEDS
AROUND 15 KT...POSSIBLY WITH GUSTS UP TO 20 KT. SIGNIFICANT SEAS
EARLY ON WILL INITIALLY DROP TO 2 TO 3 FT THRUOUT THE ILM
WATERS...THEN INCREASE TO 3 TO 4 FT ALONG AND AFTER THE COASTAL
FRONT PUSHES ONSHORE. THE NAM AND HRRR INDICATE THE FRONT TO PUSH
ONSHORE FROM CAPE FEAR NORTH AROUND DAYBREAK...AND THE REMAINING
WATERS SOUTH OF THE CAPE DURING DAYLIGHT SATURDAY.
SHORT TERM /SATURDAY THROUGH SUNDAY NIGHT/...
AS OF 3 PM FRIDAY...MAIN FORECAST CHALLENGE FOR THE MARINE
COMMUNITY WILL OCCUR EARLY IN THE PERIOD AS A FRONT THAT HAS BEEN
LINGERING OFF THE COAST MAKES A MOVE INLAND. WIND DIRECTION WILL BE
A LOW CONFIDENCE EVENT FOR SATURDAY UNTIL THE SYNOPTIC SOUTHEASTERLY
FLOW BECOMES THE DOMINANT FEATURE LATE SATURDAY. FOR NOW THE COASTAL
AREAS WILL SEE A WEST TO NORTHWEST FLOW EARLY WITH A SOUTHEASTERLY
FLOW ACROSS THE OUTER WATERS. ALL AREAS SHOULD SEE SOUTHEASTERLY
WINDS LATE SATURDAY. FOR SUNDAY A TYPICAL SUMMERTIME PATTERN OF
SOUTHERLY WINDS WILL PREVAIL. FOR THE MOST PART WIND SPEEDS WILL
REMAIN MORE REPRESENTATIVE OF SUMMER WITH 10-15 KNOTS PROBABLY
LEANING MORE TOWARD THE LOWER END OF THE RANGE. WAVEWATCH SEAS
REMAIN IN A 2-4 FOOT RANGE THROUGH THE PERIOD.
LONG TERM /MONDAY THROUGH WEDNESDAY/...
AS OF 3 PM FRIDAY...HIGH PRESSURE ACROSS THE WEST ALTAIC THE ENTIRE
TIME. THIS HIGH WILL EXTEND A RIDGE AXIS INTO THE CAROLINAS THROUGH
THE PERIOD THAT MAY VACILLATE IN BOTH STRENGTH AND LOCATION AT
TIMES. END RESULT WILL BE SMALL VARIATIONS IN WIND DIRECTION BETWEEN
SOUTH AND SOUTHWEST. WIND SPEED WILL SHOW LITTLE ENOUGH CHANGE THAT
A FORECAST OF ABOUT 10 KTS WILL HOLD FOR MOST OF THE TIME. WNA
GUIDANCE SHOWS A MINOR EASTERLY SWELL COMBINING WITH THE WIND WAVES
ON TUESDAY. OVERALL SEAS FORECAST HOWEVER TO REMAIN FAIRLY
UNCHANGING AT A GENERAL 2 TO 4 FT...HIGHEST OFFSHORE.
&&
.TIDES/COASTAL FLOODING...
AS OF 11 PM FRIDAY...HIGH TIDE AND ASSOCIATED HIGHEST GAGE
READINGS HAVE COME AND BY NOW ACROSS THE BEACHES AND NOW ACROSS
ALONG THE CAPE FEAR RIVER. MYRTLE BEACH SPRINGMAID PIER ECLIPSED
7.05 FT MLLW...WRIGHTSVILLE BEACH JOHNNY MERCER PIER AT 5.7 FT
MLLW...AND THE WILMINGTON GAGE IN THE CAPE FEAR RIVER AROUND 5.8
FT MLLW. THE NEXT HIGH TIDE CYCLES SUSCEPTIBLE TO MINOR COASTAL
FLOODING WILL OCCUR ON SATURDAY...SUNDAY AND MONDAY DURING THE MID
TO LATE EVENING HOURS.
&&
.ILM WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
NC...NONE.
MARINE...NONE.
&&
$$
NEAR TERM...TRA
SHORT TERM...SHK
LONG TERM...MBB
AVIATION...SGL/RJD
TIDES/COASTAL FLOODING...DCH
AREA FORECAST DISCUSSION
NWS BISMARCK ND
123 AM CDT SAT JUN 22 2013
.UPDATE...
ISSUED AT 122 AM CDT SAT JUN 22 2013
IN REGARDS TO CONVECTION THROUGH 12 UTC...WILL FOLLOW CLOSELY TO
THE 04 UTC HRRR AND RAP WHICH CONTINUE TO REGENERATE CONVECTION
ACROSS THE NORTHWEST AND NORTH CENTRAL IN THE RIGHT ENTRANCE
REGION OF AN UPPER LEVEL JET STREAK...WHICH MATCHES WELL WITH THE
LATEST RADAR TRENDS. OTHERWISE...THERE IS A SLIGHT CHANCE OF
THUNDERSTORMS ACROSS THE REMAINDER OF THE AREA AS THE
AFOREMENTIONED JET STREAK PROPAGATES SOUTHEAST THROUGH THE NIGHT.
DO BELIEVE THAT THE SEVERE THREAT IS QUICKLY DIMINISHING AS -10 TO
-30 HAIL CAPE VALUES HAVE FALLEN BELOW 200 J/KG AND DOWNDRAFT CAPE
VALUES BELOW 500 J/KG.
UPDATE ISSUED AT 952 PM CDT FRI JUN 21 2013
CLOUDS AND CONVECTION FARTHER SOUTH APPEARED TO BE A LIMITING
FACTOR FOR CONVECTION THIS EVENING. CURRENTLY THE NORTHWEST AND
FAR NORTH CENTRAL APPEAR TO BE THE MAIN AREAS OF FOCUS LATE THIS
EVENING ASSOCIATED WITH A WAVE LIFTING THROUGH NORTHEAST MONTANA.
HAVE ADJUSTED POPS ACCORDINGLY WITH HIGHEST POPS IN THESE AREAS
AND LOWER POPS ELSEWHERE. BUT WITH UNSTABLE AIRMASS REMAINING
ALOFT CANNOT PULL POPS COMPLETELY. CLOUD COVER MAY LIMIT FOG
DEVELOPMENT AS WELL...BUT WITH ABUNDANT MOISTURE AROUND AND NEAR
ZERO TEMP/DEWPOINT SPREADS ALREADY...WILL KEEP AREAS OF FOG IN THE
FORECAST ACROSS THE AREA TONIGHT INTO SATURDAY MORNING. NO CHANGES
TO TEMPERATURES...OTHER THAN POPULATE WITH LATEST SIGNIFICANT
WEATHER GRIDS.
UPDATE ISSUED AT 721 PM CDT FRI JUN 21 2013
QUICK UPDATE FOR EVENING POPS. NORTH A LOT OF CONVECTION OVER
WESTERN AND CENTRAL NORTH DAKOTA THIS EVENING. ONE AREA OF
CONVECTION FIRED IN NORTHERN BURLEIGH COUNTY...BUT HAS RECENTLY
DISSIPATED QUICKLY AS IT MOVED INTO A MORE STABLE ATMOSPHERE FROM
WELLS COUNTY NORTHWARD. WILL TONE DOWN POPS THIS EVENING TO MAINLY
SLIGHT CHANCE...EXCEPT ALONG THE FAR WEST WHERE CONVECTION HAS
DEVELOPED OVER EASTERN MONTANA. FOR NOW WILL LEAVE POP CHANCES
ALONE FOR THE OVERNIGHT PERIOD BUT WILL TAKE A CLOSER LOOK LATER
THIS EVENING. DID HAVE SOME STRONG WINDS OVER THE FAR SOUTHEAST
CWA DUE TO WAKE LOW FORMED FROM CONVECTION EARLIER OVER EASTERN
SOUTH DAKOTA. WINDS HERE HAVE ALSO DIMINISHED.
&&
.SHORT TERM...(THIS EVENING THROUGH SATURDAY)
ISSUED AT 254 PM CDT FRI JUN 21 2013
FORECAST HIGHLIGHTS WILL BE POSSIBLE SEVERE CONVECTION AND HEAVY
RAIN THROUGH SATURDAY.
CURRENTLY...UPPER LEVEL TROUGH OVER THE WESTERN CONUS AND A RIDGE
OVER THE MISSISSIPPI VALLEY RESULTS IN STRONG SOUTHWEST FLOW
ALOFT ACROSS THE DAKOTAS. STRONGEST CONVECTION RIGHT NOW IS OVER
SOUTH DAKOTA NEAR A STATIONARY FRONT/SFC TROUGH. EARLIER SEVERE
STORMS OVER NORTH DAKOTA QUICKLY WEAKENED AFTER 18Z AS FORCING
ALOFT DIMINISHED.
ADDITIONAL ENERGY MOVING THROUGH THE REGION IN SOUTHWEST FLOW
ALOFT STILL EXPECTED AND WILL MAINTAIN CURRENT THUNDERSTORM
PROBABILITIES AS IS FOR NOW. BEST CHANCE FOR SEVERE WEATHER WILL
CONTINUE TO BE FROM SOUTHWEST ND NORTHEAST INTO THE SOUTHERN
DEVILS LAKE BASIN WHERE THE BEST 0-6KM WIND SHEAR AND INSTABILITY
WILL BE CO LOCATED.
STORMS WILL EVENTUALLY DISSIPATE SOUTH TO NORTH TONIGHT AS FORCING
MOVES NORTH INTO CANADA. EXPECT REDEVELOPMENT OF LOW STRATUS AND
FOG WEST AND CENTRAL TONIGHT.
REDEVELOPMENT OF CONVECTION ON SATURDAY AS ADDITIONAL WAVES ADVECT
THROUGH THE NORTHERN PLAINS.
.LONG TERM...(SATURDAY NIGHT THROUGH FRIDAY)
ISSUED AT 254 PM CDT FRI JUN 21 2013
UPPER TROUGH WILL TRAVERSE ACROSS NORTH DAKOTA SUNDAY WITH MORE
SHOWERS AND THUNDERSTORMS. A BIT OF A BREAK SUNDAY NIGHT...BUT WITH
A PROGRESSIVE SOUTHWEST FLOW PERSISTING INTO TUESDAY NIGHT...EXPECT
A COUPLE MORE SHORTWAVES TO SHIFT THROUGH WITH ADDITIONAL CHANCES OF
FOR SHOWERS/THUNDERSTORMS. WEDNESDAY THROUGH FRIDAY...STILL
EXPECTING AN UPPER RIDGE TO DEVELOP OVER THE FOUR CORNERS DURING THE
PERIOD WITH THE RIDGE AXIS AMPLIFYING INTO SOUTHERN CANADA. A
COMPENSATORY NORTHWEST FLOW DEVELOPS INTO WESTERN AND CENTRAL NORTH
DAKOTA THURSDAY AND FRIDAY. THERE COULD BE A COUPLE OF RIDGE TOPPERS
SLIDING THROUGH RESULTING IN A CHANCE FOR SHOWERS AND THUNDERSTORMS
MAINLY IN EAST CENTRAL NORTH DAKOTA...WITH THE WEST REMAINING MORE
STABLE AND DRIER.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY EVENING)
ISSUED AT 122 AM CDT SAT JUN 22 2013
MVFR TO IFR STRATUS AND FOG IS EXPECTED TO DEVELOP OVER MOST OF
WESTERN AND CENTRAL NORTH DAKOTA TONIGHT AND CONTINUE THROUGH
APPROXIMATELY 14-15 UTC SATURDAY. THE BEST CHANCES FOR
THUNDERSTORMS ON SATURDAY WILL BE ACROSS WESTERN AND NORTH CENTRAL NORTH
DAKOTA...INCLUDING KISN...KMOT AND KDIK WHERE THUNDERSTORMS MAY
CONTINUE TO REGENERATE MUCH OF THE DAY. OTHERWISE...BELIEVE THE
THREAT FOR STORMS WILL HOLD OFF UNTIL APPROXIMATELY 20-22 UTC FOR
KBIS AND AFTER 05 UTC AT KJMS SATURDAY NIGHT.
&&
.HYDROLOGY...
ISSUED AT 254 PM CDT FRI JUN 21 2013
WILL MAINTAIN THE FLASH FLOOD WATCH AS IS WITH CONTINUED CHANCES
FOR STRONG TO SEVERE THUNDERSTORMS NOW THROUGH SUNDAY...WITH
ADDITIONAL HEAVY RAINFALL POSSIBLE FOR THOSE LOCATIONS THAT HAVE
SEEN SIGNIFICANT RAINFALL AMOUNTS WEDNESDAY NIGHT AND THURSDAY
EVENING ACROSS SOUTH CENTRAL NORTH DAKOTA AND THE JAMES RIVER
VALLEY. SOILS HAVE LITTLE TO NO CAPACITY TO HOLD ADDITIONAL
WATER...ENHANCING RUNOFF AND THE POTENTIAL TO AGGRAVATE THE
ONGOING OVERLAND FLOODING ACROSS THE AREA. A COMPLEX OF
THUNDERSTORMS WITH HEAVY RAINFALL IS POSSIBLE AGAIN SATURDAY NIGHT
INTO SUNDAY. ADDITIONAL RAINFALL AMOUNTS OF 1 TO 3 INCHES ARE
POSSIBLE WITH LOCALLY HIGHER AMOUNTS.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
FLASH FLOOD WATCH THROUGH SUNDAY EVENING FOR NDZ023-025-036-037-
046>048-050-051.
&&
$$
UPDATE...AYD
SHORT TERM...NH
LONG TERM...KS
AVIATION...TWH
HYDROLOGY...NH
AREA FORECAST DISCUSSION...UPDATED
NWS LUBBOCK TX
1143 PM CDT FRI JUN 21 2013
.UPDATE...
CONVECTION WAS WINDING DOWN AT THIS HOUR. LIGHT SHOWERS AND A FEW
ISOLATED THUNDERSTORMS WERE THE ONLY ACTIVITY THAT REMAINED.
THEREFORE THE SEVERE THUNDERSTORM WATCH WAS CANCELLED.
&&
.AVIATION...
A FEW LIGHT SHOWERS REMAINED THIS EVENING BUT ARE NOT EXPECTED TO
AFFECT EITHER TAF SITE. A WEAK OUTFLOW BOUNDARY MAY BRIEFLY SHIFT
WINDS TO THE NORTH AT KLBB WITHIN THE NEXT ONE TO TWO HOURS BUT
WIND SPEEDS ARE ANTICIPATED TO BE LIGHT. SOUTHERLY WINDS WILL
INCREASE AGAIN ON SATURDAY AFTERNOON AND MAY LEAD TO LIGHT
VISIBILITY RESTRICTIONS DUE TO BLOWING DUST. ANOTHER CHANCE OF
THUNDERSTORMS WILL ALSO EXIST SATURDAY EVENING BUT CONFIDENCE IS
NOT HIGH ENOUGH TO PLACE IN THE TAF AT THE MOMENT.
&&
.PREV DISCUSSION... /ISSUED 652 PM CDT FRI JUN 21 2013/
UPDATE...
DISTURBANCE EDGING INTO WESTERN NEW MEXICO EXPECTED TO LEAD TO
INCREASING THUNDERSTORMS THROUGH THE EVENING...SHOULD PERSIST
LATER THAN LAST NIGHT. INITIAL ACTIVITY NEAR THE NEW MEXICO BORDER
FAIRLY ISOLATED AND STILL UNCERTAIN HOW MUCH ADDITIONAL DEVELOPMENT
WILL OCCUR...MIXED SIGNALS FROM SHORT-TERM SOLUTIONS. HAIL AND
HIGH WIND THREAT SHOULD TRANSITION TO OUTFLOW DRIVEN STORMS WITH
WIND AND DUST AS PROBABLE ISSUES. SEVERE THUNDERSTORM WATCH VALID
UNTIL 2 AM CDT TONIGHT. RMCQUEEN
AVIATION...
A FEW ISOLATED THUNDERSTORMS HAVE DEVELOPED NEAR THE TEXAS/NEW
MEXICO STATE LINE AND WILL CONTINUE TO MOVE EAST THIS EVENING.
HOWEVER...CONFIDENCE IS LOW ON WHETHER ANY STORMS WILL AFFECT EITHER
TAF SITE. WINDS WILL PICK UP TOMORROW AFTERNOON AGAIN AND LEAD TO
LIGHT VISIBILITY RESTRICTIONS DUE TO BLOWING DUST.
PREV DISCUSSION... /ISSUED 316 PM CDT FRI JUN 21 2013/
SHORT TERM...
FORECAST REVOLVES AROUND THUNDER CHANCES LATE THIS AFTERNOON INTO
TONIGHT. THE REGION REMAINS UNDER SOUTHWEST FLOW ALOFT...WITH ONE
NOTABLE SHORTWAVE TROUGH ACROSS THE PANHANDLES EXITING TO THE
NORTHEAST AND ANOTHER AREA OF LIFT SEEN ON WATER VAPOR IMAGERY
APPROACHING THROUGH AZ. WAS CONCERNED THE FIRST WAVE COULD SPARK A
FEW STORMS ACROSS THE EASTERN ZONES THIS AFTERNOON...AS EARLIER RAP
AND HRRR SOLUTIONS SUGGESTED...BUT THEY HAVE NOW BACKED OFF ON THIS
AND WITH WAVE EXITING PROSPECTS FOR THIS ARE LOW. ALTHOUGH WE WILL
BE POSITIONED BETWEEN THE TWO SYNOPTIC AREAS OF FORCING FOR ASCENT
THIS EVENING...STRONG HEATING AND GOOD MOISTURE LEVELS WERE
RESULTING IN STRONG INSTABILITY AND MINIMAL INHIBITION OVER MUCH OF
THE REGION...WITH 19Z MLCAPE VALUES ANALYZED AOA 2500 J/KG FOR MOST
OF THE FA. IN ADDITION...AN AREA OF LOW-LEVEL MOISTURE CONVERGENCE
WAS NOTED FROM THE CENTRAL TEXAS PANHANDLE SOUTHWESTWARD INTO THE
LEE TROUGH ACROSS SOUTHEASTERN NEW MEXICO. UP TO THIS POINT...STORMS
HAVE BEEN CONFINED TO LOCATIONS IMMEDIATELY ALONG AND EAST OF THE
SACRAMENTO MOUNTAINS...BUT EXPECT ADDITIONAL DEVELOPMENT
NORTHEASTWARD FROM THERE UP INTO THE WESTERN/CENTRAL PANHANDLE
THROUGH LATE THIS AFTERNOON. THE ACTIVITY MAY TRY AND CONGEAL
SOMEWHAT AS IT MOVES EASTWARD ACROSS THE CAPROCK THIS
EVENING...PERHAPS MAKING IT INTO THE ROLLING PLAINS LATER
TONIGHT...THOUGH IT SHOULD BE WANING IN INTENSITY BY LATE EVENING.
EARLY ON...STRONG INSTABILITY AND WEAK TO MODEST WIND SHEAR WILL
SUPPORT A SEVERE THREAT WITH LARGE HAIL...DAMAGING WINDS...LOCALLY
HEAVY RAIN AND THE PROSPECTS FOR BLOWING DUST. HAVE EXPANDED CHANCE
POPS TO ENCOMPASS NEARLY THE ENTIRE SOUTHERN PANHANDLE AND SOUTH
PLAINS THROUGH 06Z BEFORE DROPPING POPS BELOW 15 PERCENT AFTER 06Z.
TEMPERATURES TONIGHT WILL BE MILD AS MOIST SOUTHERLY LOW-LEVEL FLOW
CONTINUES AND HAVE GONE WITH TEMPERATURES SIMILAR TO WHAT WE SAW
THIS MORNING.
TOMORROW WILL BRING ANOTHER HOT DAY WITH LITTLE CHANGE IN THE
OVERALL PATTERN. STRONG DAYTIME HEATING...WITH HIGHS IN THE MIDDLE
90S AND SUFFICIENT MOISTURE...COMBINED WITH CONVERGENCE ALONG A SFC
TROUGH/DRYLINE WILL BRING ANOTHER THREAT OF STRONG/SEVERE
STORMS...FAVORING THE WESTERN ZONES INITIALLY IN THE LATE AFTERNOON
HOURS...THEN EXPANDING EAST.
LONG TERM...
MAIN ISSUE TODAY IS TIMING TRANSITION FROM AFTN THUNDERSTORM
REGIME ACROSS THE WRN ZONES TO HOT AND DRY AREAWIDE. 12Z MODEL
RUNS NOW A BIT SLOWER IN REPLACING THE WRN CONUS UPPER TROUGH WITH
AN AMPLIFYING RIDGE. IT NOW LOOKS LIKE THE LEE SFC TROUGH COULD
REMAIN ACTIVE INTO MONDAY WITH SWLY FLOW ALOFT BEFORE THAT RIDGE
AMPLIFICATION BEGINS OVER THE SRN ROCKIES. THAT SHOULD FINALLY
SHUT PRECIPITATION DOWN OVER THE AREA. AS A RESULT HAVE EXTENDED
SLIGHT CHANCE MENTION INTO MONDAY AFTN AND EVENING. TEMPS WILL
THEN WARM AS THE RIDGE BUILDS OVER THE ROCKIES AND LOW LEVELS DRY
OUT A BIT...WITH HIGH TEMPS LIKELY APPROACHING 10F WARMER THAN
NORMAL BY WEDNESDAY AND THURSDAY. WILL END WITH MENTION OF AN
OUTSIDE SHOT OF PRECIP REENTERING THE PICTURE TOWARD FRIDAY AS
NORTHERLY MID TO UPPER FLOW OVER THE PLAINS COULD SEND A COLD
FRONT AND/OR UPPER DISTURBANCE TOWARD THE FCST AREA. FOR NOW THAT
POSSIBILITY TOO REMOTE TO ADD TO FCST.
&&
.PRELIMINARY POINT TEMPS/POPS...
FRIONA 64 93 63 94 63 / 30 20 20 20 20
TULIA 66 94 66 96 67 / 30 20 20 20 20
PLAINVIEW 68 93 68 95 68 / 30 20 20 20 20
LEVELLAND 69 93 68 93 69 / 30 20 20 20 20
LUBBOCK 73 93 70 96 69 / 30 10 20 20 20
DENVER CITY 67 95 68 96 69 / 30 20 20 20 20
BROWNFIELD 70 94 68 95 70 / 30 20 20 20 20
CHILDRESS 72 97 70 97 70 / 20 10 10 10 10
SPUR 72 95 71 95 70 / 20 10 10 10 10
ASPERMONT 73 97 72 97 71 / 20 10 10 10 10
&&
.LUB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
01
FORECAST DISCUSSION FOR ROUTINE MORNING FORECAST ISSUANCE
.SHORT TERM...TODAY...TONIGHT...AND SUNDAY
ISSUED AT 442 AM CDT SAT JUN 22 2013
CONTINUE WITH ISSUES ON WHERE AND WHEN CONVECTION WILL AFFECT
AREA. WATER VAPOR IMAGERY SHOWING NUMBER OF DISTURBANCES MOVING
THROUGH SOUTHWEST FLOW ALOFT OVER UPPER MIDWEST. CONVECTION
ASSOCIATED WITH THESE DISTURBANCES CURRENTLY EXTENDS OVER SOUTHERN
WI THROUGH MN AND NEBRASKA. MAIN ISSUES TONIGHT WITH THE
CONVECTION...HEAVY RAIN. IR IMAGERY SHOWING WARMING TOPS ATTM WITH
DOWNWARD TREND EXPECTED TO CONTINUE INTO THE MORNING HOURS. OVER
NORTHEAST WI...STABLE AIR FILTERED SOUTH BEHIND BOUNDARY DROPPING
SOUTH OUT OF LAKE SUPERIOR DURING THE EVENING. MODEL OF CHOICE
QUESTIONABLE...WHILE GFS AND TO SOME EXTENT EC APPEARED TO BE
DOING WELL AT 6Z WITH CONVECTIVE TRENDS...THEY QUICKLY LOSE
REALITY AS MOVE INTO THIS MORNING. HAVE TRENDED TOWARDS CURRENT
RADAR TRENDS AND HRRR WHICH BRINGS WAINING CONVECTION NORTH INTO
CENTRAL AND NORTH CENTRAL WI THIS MORNING. THUS WILL GO HIGH
CHANCE OR LIKELY OVER THESE LOCATIONS FOR FIRST PART OF DAY.
REMAINDER OF AREA...LOWER CHANCE POPS THROUGH THE DAY. HRRR
SUGGEST LIMITED PCPN THROUGH AFTERNOON. THIS MAKES SENSE AS BEST
FORCING/ ISENTROPIC LIFT WEST OVER SOUTHERN MN THIS
AFTERNOON...EVENING. MODELS CONTINUE TO TRY AND BRING WARM FRONT
NORTH THROUGH THE AREA TONIGHT. WITH UNCERTAINTY...WILL STICK TO
CHANCE POPS THROUGH SUN. COLD FRONT APPROACHES STATE LATE IN DAY
SUN AS MAIN UPPER WAVE LIFTS NORTHEAST THROUGH HIGH PLAINS.
TRENDED POPS HIGHER WEST GIVEN PROXIMITY OF FRONT.
AGAIN OVERNIGHT STORMS PRODUCED SIG PCPN AS HAVE PLENTY OF
MOISTURE TO WORK WITH WITH PW`S IN 1.5 TO 2.0 INCH RANGE. THIS TO
CONTINUE INTO SUNDAY. PLENTY OF INSTABILITY AROUND THROUGH THE
PERIOD...THOUGH SHEAR IS LIMITED AT LEAST UNTIL SUN...WHEN MODELS
SUGGEST INCREASES TO NR 40 KTS. WILL CONTINUE TO HIGHLIGHT HEAVY
RAIN POTENTIAL AS MAIN ISSUE...WITH STRONG DAMAGING WIND THREAT
POSSIBLE TODAY AND TONIGHT.
GIVEN LOW CLOUDS/CLOUDS EXPECTED FOR FIRST HALF OF DAY AND
EASTERLY COMPONENT OF WIND...HAVE DROPPED HIGHS A GOOD 5 DEGS
TODAY. HAVE NOT MADE ANY SIG CHANGE TO SUN ATTM DUE TO UNCERTAINTY
ON CONVECTION.
.LONG TERM...SUNDAY NIGHT THROUGH FRIDAY
ISSUED AT 442 AM CDT SAT JUN 22 2013
UPPER RIDGE WILL GRADUALLY RETROGRADE WESTWARD INTO THE WESTERN
UNITED STATES. THIS WILL EVENTUALLY CHANGE THE SOUTHWEST FLOW
PATTERN TO A NORTHWEST FLOW PATTERN...BRINGING COOLER TEMPERATURES
AND LOWER HUMIDITY BY THE END OF THE WEEK.
CONSIDERING MODELS ARE HAVING TOUGH TIME OVER THE LAST FEW DAYS
IN THE PLACEMENT OF CONVECTION AND LOCALLY HEAVY RAIN...LOWER
THAN NORMAL CONFIDENCE IN THE DETAILS OF THE FORECAST AS THE MODELS
CONTINUE TO SHOW SEVERAL COMPLEXES MOVING ACROSS THE WESTERN GREAT
LAKES EARLY TO MIDDLE OF NEXT WEEK. THEREFORE...WILL CONTINUE CHANCES
OF SHOWERS AND THUNDERSTORMS EACH DAY THROUGHOUT THE PERIOD. SOME
INDICATIONS BY THE MODELS THAT MONDAY COULD END UP BEING DRIER THAN
ADVERTISED...BUT WILL BELIEVE IT WHEN I SEE IT.
STILL THE POTENTIAL FOR SEVERE WEATHER AND LOCALLY HEAVY EARLY TO
MIDDLE PORTIONS OF NEXT WEEK. HAZARDOUS WEATHER OUTLOOK HAS THIS
MENTIONED ALONG WITH THE UNCERTAINTY IN TIMING. ONLY MINOR CHANGES
MADE TO THE EXTENDED FORECAST ON A FEW DAYS...MORE COORDINATION
PURPOSES.
&&
.AVIATION...FOR 06Z TAF ISSUANCE
ISSUED AT 1048 PM CDT FRI JUN 21 2013
INITIAL CLUSTER OF TSTMS HAS WEKENED AS IT MOVED TOWARD CENTRAL
WI LATE THIS EVENING. ALTHOUGH THE FIRST ROUND OF STORMS SHOULD MISS
THE TAF SITES...THERE SHOULD STILL BE A CHANCE OF STORMS ACROSS
MUCH OF C/EC WI OVERNIGHT. MVFR CONDITIONS MAY ACCOMPANY THE TSTMS.
LOW CLOUDS WILL BE FOUND ACROSS NORTHERN WI OVERNIGHT...AND MAY
ALSO BE OCCUR ACROSS C/EC WI LATE TONIGHT INTO EARLY SAT. IMPROVING
CONDITIONS ARE EXPECTED BY MID TO LATE SAT MORNING...WITH SCT TSTMS
REDEVELOPING DURING THE LATE AFTERNOON/EARLY EVENING. STRONG INSTABILITY
IS EXPECTED...SO STRONG/SEVERE TSTMS WITH TORRENTIAL RAINFALL ARE
POSSIBLE.
&&
.GRB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM.....TE
LONG TERM......ECKBERG
AVIATION.......KIECKBUSCH
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
1213 AM CDT SAT JUN 22 2013
.SHORT TERM...(THIS EVENING THROUGH SATURDAY)
ISSUED AT 355 PM CDT FRI JUN 21 2013
AT 3 PM...A THUNDERSTORM COMPLEX WAS LOCATED OVER EASTERN SOUTH
DAKOTA. THE HRRR SEEMS TO BE HANDLING THIS SYSTEM THE BEST THIS
AFTERNOON. IT SHOWS THAT THIS SYSTEM WILL MOVE NORTHEAST INTO
NORTHEAST SOUTH DAKOTA AND WEST CENTRAL MINNESOTA LATE THIS
AFTERNOON AND EARLY EVENING. THIS SYSTEM IS INITIALLY FOLLOWING THE
SHORT WAVE TROUGH. HOWEVER AS THE LOW LEVEL JET STRENGTHENS THIS
EVENING AND STRONG 850 MB MOISTURE TRANSPORT WILL MOVE INTO THE
FORECAST AREA. EXPECT SOME DEVELOPMENT ALONG THE ADVANCING WARM
FRONT ON THE SOUTH OF THIS PERIPHERY OF THIS SYSTEM. MLCAPES ALONG
THIS BOUNDARY CLIMB TO AROUND 5000 J/KG LATE THIS AFTERNOON AND
THEN CONTINUES INTO THE EARLY EVENING. WHILE THE 0-6 KM SHEAR IS
NOT FAVORABLE FOR SUPERCELLS...THE 0-3 KM BULK SHEAR IS OVER
40 KNOTS AND IT WILL BE FAVORABLE FOR DAMAGING WINDS. IN ADDITION
WITH DCAPES OVER 1500 J/KG...THIS WOULD ALSO MAKE IT FAVORABLE FOR
THE STORMS TO PRODUCE DAMAGING WINDS. CURRENTLY EXPECTING THE
CURRENT CONVECTION TO EVOLVE INTO 1 OR MORE BOW ECHOS AS THEY
BECOME MORE COLD POOL DOMINANT...AND THESE LINES WOULD LIKELY MOVE
ALONG OR NORTH OF THE INTERSTATE 90 CORRIDOR BETWEEN 22.03Z AND
22.09Z. HOWEVER IF THE BOUNDARY DOES NOT LIFT AS FAR NORTH AS THE
MESO MODELS INDICATE...THIS CONVECTION COULD POTENTIALLY BE
FURTHER SOUTH TONIGHT.
FLASH FLOODING IS ALSO A CONCERN TONIGHT AS WARM CLOUD LAYER
DEPTHS CLIMB INTO THE 4 TO 4.5 KM RANGE AND PRECIPITABLE WATER
VALUES CLIMB INTO THE 1.8 TO 2.0 INCH RANGE. WITH THE LOW LEVEL
JET CONTINUING TO IMPINGE ON THE FRONT NEAR THE MINNESOTA AND IOWA
BORDER...EXPECT CONVECTION TO CONTINUE TO DEVELOP ACROSS EASTERN
NEBRASKA...WESTERN IOWA AND SOUTHWEST MINNESOTA THROUGHOUT THE
NIGHT. THIS CONVECTION WOULD THEN TRAIN INTO THE FORECAST AREA
WITH THE MEAN WIND. WOULD NOT BE SHOCKED TO SEE 3 TO 5 INCHES OF
RAIN FALL ACROSS PARTS OF THE AREA TONIGHT. THERE MAY BE EVEN SOME
LOCALLY HIGHER AMOUNTS. THIS LOOKS LIKE A CLASSIC MADDOX WARM
FRONTAL FLASH FLOOD EVENT. DUE TO THIS...ISSUED A FLASH FLOOD
WATCH FOR TONIGHT AND SATURDAY MORNING. THE SHOWERS AND
THUNDERSTORMS WILL GRADUALLY DIMINISH ON SATURDAY MORNING AS THE
LOW LEVEL JET WEAKENS.
ON SATURDAY AFTERNOON...THE MODELS SHOW THAT THE WARM FRONT WILL MOVE
NORTHWARD TOWARD THE INTERSTATE 94 CORRIDOR. WITH THERE NOT MUCH
MOISTURE CONVERGENCE ALONG THIS FRONT AND SOME CAPPING
ALOFT...THERE IS A POTENTIAL THAT THE COULD BE SOME DRY HOURS.
.LONG TERM...(SATURDAY NIGHT THROUGH FRIDAY)
ISSUED AT 355 PM CDT FRI JUN 21 2013
ON SATURDAY NIGHT...MANY OF THE DETERMINISTIC MODELS SUGGEST THAT
THE 850 MB MOISTURE TRANSPORT WILL SHIFT NORTHEAST OF THE AREA BY
LATE EVENING. AS A RESULT...MANY OF THESE MODELS HAS THE FORECAST
AREA DRYING OUT DURING THE 23.06Z TO 23.12Z TIME FRAME. IF THIS
TREND CONTINUES...MAY HAVE TO LOWER OR POSSIBLY TAKE THESE
PRECIPITATION CHANCES OUT OF THE FORECAST.
FROM SUNDAY INTO TUESDAY...THE MODELS CONTINUE TO STRUGGLE WITH
THE LOCATION OF THE FRONT AND WHERE MESOSCALE COMPLEXES MAY
DEVELOP. AS A RESULT...THE FORECAST CONFIDENCE FOR THE TIMING AND
LOCATION OF THE PRECIPITATION IS NOT AS CERTAIN. DUE TO
THIS...STAYED WITH THE CONSALL PRECIPITATION CHANCES AND ALSO WITH
THEIR MAXIMUM AND MINIMUM TEMPERATURES. ON ANY OF THESE
DAYS...TEMPERATURES COULD EASILY CLIMB INTO THE LOWER 90S IF
ENOUGH SUNSHINE CAN OCCUR.
FROM WEDNESDAY INTO FRIDAY...THE DETERMINISTIC MODELS ARE SHOWING
THAT THE UPPER LEVEL RIDGE WILL RETROGRADE INTO THE WESTERN UNITED
STATES AND WESTERN CANADA. THIS IS IN RESPONSE TO A MODERATE
MADDEN JULIAN OSCILLATION MOVING TOWARD THE INTERNATIONAL DATELINE.
WHEN THIS OCCURS IN SUMMER...CLIMATE PREDICTION CENTER COMPOSITES
FAVOR ABOVE NORMAL TEMPERATURE ANOMALIES ACROSS THE WESTERN UNITED
STATES. AS A RESULT...CONFIDENCE IS HIGH THAT THIS WILL
OCCUR...BUT THE EXACT TIME WHEN THIS WILL ULTIMATELY TAKE PLACE IS
STILL A BIT UNCERTAIN.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT)
ISSUED AT 1212 AM CDT SAT JUN 22 2013
CONVECTION HAS BEEN STEADILY INCREASING SOUTH OF THE TAF SITES
THIS EVENING AS THE LOW LEVEL JET INTERSECTS THE SURFACE BOUNDARY
SITTING ACROSS NORTHEAST IOWA. EXPECT TO SEE THIS AREA FILL IN
WITH CONVECTIVE ACTIVITY AND LIFT TO THE NORTH AND THEN MERGE WITH
THE ACTIVITY COMING IN FROM SOUTHERN MINNESOTA. THIS ACTIVITY
SHOULD THEN PROGRESS EAST ACROSS THE REGION DURING THE LATE NIGHT
HOURS INTO EARLY SATURDAY MORNING. CAN NOT RULE OUT SOME GUSTY
WINDS UNTIL THE MAIN BAND OF STORMS FROM THE WEST PASSES THROUGH
ALONG WITH IFR CONDITIONS IN THE RAIN. ONCE THE MAIN BAND GOES
THROUGH SHOULD CONTINUE TO SEE SOME SHOWERS AND OCCASIONAL
THUNDERSTORMS FOR A COUPLE OF HOURS WITH MVFR CONDITIONS POSSIBLE.
EXPECTING A RETURN TO VFR CONDITIONS ONCE THE RAIN ENDS AND THEN
THE QUESTION BECOMES WHEN AND WHERE THE NEXT ROUND OF CONVECTION
WILL FORM. THE 21.12Z HI-RES ARW HAS BEEN DOING A DECENT JOB IN
THIS PATTERN AND SHOWS THE SURFACE BOUNDARY REMAINING SOUTH OF THE
TAF SITES WITH ACTIVITY DEVELOPING IN THE LATE AFTERNOON AND
CONTINUING INTO THE EVENING AS THE NEXT SHORT WAVE TROUGH COMES
TOWARD THE AREA. CONFIDENCE ON THE TIMING AND PLACEMENT OF THIS IS
NOT HIGH ENOUGH TO GO BEYOND A VCTS AT THIS TIME.
&&
.HYDROLOGY...TONIGHT INTO SATURDAY
ISSUED AT 355 PM CDT FRI JUN 21 2013
OVERNIGHT 1 TO 2 INCHES OF RAIN FELL ACROSS SOUTHEAST
MINNESOTA...AND WEST CENTRAL AND NORTH CENTRAL WISCONSIN...AND
2 TO 4 INCHES FELL ACROSS NORTHEAST IOWA...AND SOUTHWEST AND
CENTRAL WISCONSIN. THIS CAUSED RIVER FLOOD WARNINGS TO BE ISSUED
ALONG THE BLACK AND KICKAPOO RIVERS IN WESTERN WISCONSIN. AS A
STRONG LOW LEVEL JET BRINGS ABUNDANT MOISTURE INTO THE AREA
TONIGHT. EXPECT THAT 3 TO 5 INCHES MAY FALL ACROSS PARTS OF THE
AREA TONIGHT. A FEW LOCAL SPOTS MAY SEE EVEN HIGHER AMOUNTS.
THINKING THAT THE BEST CHANCES ARE ALONG AND NORTH OF THE
INTERSTATE 90 CORRIDOR. HOWEVER THERE IS STILL SOME UNCERTAINTY IN
THIS. THIS ADDITIONAL RAIN WILL LIKELY RESULT IN SOME FLASH
FLOODING TONIGHT. AS A RESULT...WENT WITH A FLASH FLOOD WATCH FOR
THE ENTIRE AREA TONIGHT.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...FLASH FLOOD WATCH THROUGH SATURDAY MORNING FOR WIZ017-029-
032>034-041>044-053>055-061.
MN...FLASH FLOOD WATCH THROUGH SATURDAY MORNING FOR MNZ079-086>088-
094>096.
IA...FLASH FLOOD WATCH THROUGH SATURDAY MORNING FOR IAZ008>011-018-
019-029-030.
&&
$$
SHORT TERM...BOYNE
LONG TERM...BOYNE
AVIATION...04
HYDROLOGY...BOYNE
AREA FORECAST DISCUSSION
NWS CHEYENNE WY
1127 PM MDT FRI JUN 21 2013
.UPDATE...
ISSUED AT 1025 PM MDT FRI JUN 21 2013
CONVECTION CONTINUES TO WIND DOWN ACROSS THE CWA AS THE
ATMOSPHERE STABILIZES. ALTHOUGH A FEW LIGHT SHOWERS AND EMBEDDED
THUNDERSTORMS WILL STILL BE A POSSIBILITY ACROSS EASTERN AND
NORTHERN ZONES THROUGH THE REST OF THE NIGHT...NO LONGER EXPECT
THE POSSIBILITY OF SEVERE WEATHER. SO...HAVE LET THE SEVERE
THUNDERSTORM WATCH EXPIRE AT 10 PM. INITIAL GLANCE AT 00Z MODEL
DATA CONTINUES TO POINT TO ANOTHER ACTIVE DAY ON SATURDAY. HAHN
&&
.SHORT TERM...(THIS EVENING THROUGH SUNDAY NIGHT)
ISSUED AT 300 PM MDT FRI JUN 21 2013
BELIEVE WE ARE PRIMED FOR A SEVERE WEATHER EPISODE THIS AFTERNOON.
CONDITIONS ARE SET FOR SEVERE THUNDERSTORMS. CHALLENGES ARE WHERE
AND WHEN.
CURRENTLY...STRATUS LAYER ON VISIBLE IMAGERY CONTINUES TO ERODE
ACROSS DAWES AND SIOUX COUNTIES IN THE PANHANDLE AND NIOBRARA
COUNTY IN EAST CENTRAL WYOMING. DEWPOINTS REMAIN EXTREMELY HIGH
(FOR OUR NECK OF THE WOODS)...IN THE PANHANDLE. ALLIANCE STILL
REPORTING A DEW POINT OF 67 DEGREES...WITH LOW TO MID 60S
ELSEWHERE. LATEST STORM PREDICTION CENTER MESOANALYSIS SHOWING
CAPE ALREADY IN MOST OF THE PANHANDLE OF 4500 TO 5000 J/KG. ALL
THAT IS NEEDED IS A LIFTING MECHANISM AND THAT IS DEVELOPING. A
DRY LINE LAYS ACROSS EXTREME SOUTHEASTERN WYOMING...ROUGHLY FROM
JUST EAST OF CHEYENNE TO JUST WEST OF TORRINGTON AND THEN
NORTHWEST TO DOUGLAS. BEHIND THIS LINE...DEWPOINTS HAVE FALLEN
INTO THE 20S. ALONG THIS LINE...SEEING CU DEVELOPING ALONG THE
LINE. HAVE A PRETTY GOOD CELL ALREADY DEVELOPING IN NORTHERN
LARAMIE COUNTY AND SOUTHERN GOSHEN COUNTY. THIS IS MOST LIKELY THE
START OF OUR EVENT. JUST RECEIVED A SWOMCD FROM SPC AT 113 PM STATING
A WATCH IS LIKELY...SO ANOTHER HOUR OR SO...CONVECTION SHOULD
INITIATE.
LATEST HRRR COMPOSITE REFLECTIVITY FORECAST SHOWING THAT CELL IN
SOUTHERN GOSHEN COUNTY TAKING OFF AROUND 3 PM. BY THAT TIME...LOW
STRATUS SHOULD BE MIXED OUT OVER THE NORTHERN PANHANDLE. SUPER CELL
THEN MOVES EAST INTO THE CENTRAL PANHANDLE. WITH SUCH LARGE
CAPE...GOING TO SEE SOME VERY LARGE HAIL REPORTS. NAM/WRF FORECAST
SOUNDINGS CONTINUE TO SHOW STRONGLY VEERING WINDS WITH
NORTHEASTERLY TO EASTERLY SURFACE WINDS AND 35-40KT SOUTHWESTERLY
WINDS AT 700MBS. MORE THAN ENOUGH SHEAR TO SUPPORT SUPERCELLS
CONTINUING INTO THE PANHANDLE. LATEST NAM HELICITIES FOR LATER
THIS AFTERNOON/EVENING SHOWING 150M2/S2...INCREASING TO OVER
300M2/S2 OVER CONVERSE AND NIOBRARA COUNTIES AFTER 00Z...SPREADING
INTO THE NORTHERN PANHANDLE AFTERWARDS. LCLS QUITE LOW UP THERE AS
WELL...SO THE TORNADO THREAT WILL LIKELY BE FROM 23Z THROUGH MAYBE
02 TO 03Z TIME FRAME. SEVERE THUNDERSTORMS COULD LAST WELL INTO THE
EVENING AND OVERNIGHT HOURS IN THE PANHANDLE.
FOR SATURDAY...PRETTY MUCH A REPEAT OF TODAY WITH SEVERE
THUNDERSTORMS OVER EAST CENTRAL WYOMING AND NEBRASKA PANHANDLE.
SHOULD BEGIN TO SEE A DECREASE IN LOW LEVEL MOISTURE SUNDAY AS
WINDS SHIFT TO THE SOUTHWEST. COULD STILL SEE SOME SEVERE
THUNDERSTORMS IN THE PANHANDLE SUNDAY AFTERNOON.
.LONG TERM...(MONDAY THROUGH FRIDAY)
ISSUED AT 300 PM MDT FRI JUN 21 2013
DUE TO THE THREAT OF SEVERE WEATHER THIS AFTERNOON...WILL KEEP
LONG TERM DISCUSSION BRIEF SINCE NOT MUCH HAS CHANGED SINCE
YESTERDAY.
MODELS CONTINUING TO SHOW SOUTHWEST FLOW ALOFT AND RELATIVELY
QUIET WEATHER FOR NEXT WEEK. THERE APPEARS TO BE LITTLE IN THE WAY OF
RAINFALL CHANCES ACROSS SOUTHEAST WYOMING NEXT WEEK...WITH A
SLIGHTLY BETTER CHANCE ACROSS WESTERN NEBRASKA ON MONDAY AHEAD OF
A WEAK COOL FRONT. MODELS SHOW THIS PACIFIC FRONT SLIDING
EASTWARD ACROSS THE NORTHERN ROCKIES MONDAY NIGHT AND INTO
TUESDAY. THE GFS AND THE GEM HAVE TRENDED TOWARDS THE ECMWF
SOLUTION...SHOWING THE FRONT STALLING FURTHER TO THE NORTH AS THE
UPPER LEVEL TROUGH IS FURTHER NORTH AS WELL AND MORE PROGRESSIVE.
THE MAIN IMPACT FROM THIS FRONT WILL BE WINDY CONDITIONS...MAINLY
WEST OF THE LARAMIE RANGE ON MONDAY AND TUESDAY. TEMPERATURES WILL
NOT LOWER MUCH...IF AT ALL...ESPECIALLY FURTHER SOUTH NEAR THE I80
CORRIDOR. THERE APPEARS TO BE A BETTER CHANCE OF TSTORMS AHEAD OF
THIS FRONT ON MONDAY...AS A WEAK SHORTWAVE MOVES NORTHEAST ACROSS
THE HIGH PLAINS. INCREASED POP MONDAY AND MONDAY EVENING MAINLY
ACROSS WESTERN NEBRASKA. AFTER THAT...MODELS ALL INDICATE A STRONG
UPPER LEVEL HIGH DEVELOPING AND INTENSIFYING NEAR THE FOUR
CORNERS REGION BY WEDNESDAY AND THURSDAY. THIS WILL RESULT IN A
PERIOD OF LIGHT WINDS BUT ALSO VERY WARM OR HOT TEMPERATURES
THROUGH LATE NEXT WEEK. WITH THE EXCEPTION OF MONDAY...KEPT POP
BELOW 10 PERCENT THROUGH THE WEEK. HIGH TEMPERATURES WILL CONTINUE
TO BE ABOVE NORMAL AND GENERALLY IN THE 80S AND 90S. THIS UPPER
LEVEL HIGH WILL BEGIN TO DRIFT WESTWARD BY LATE IN THE
WEEK...ALLOWING A CANADIAN COLD FRONT TO PUSH SOUTH. THIS MAY
INCREASE PRECIPITATION AND TSTORM CHANCES BY NEXT WEEKEND DUE
FAVORABLE EASTERLY FLOW BEHIND THE BOUNDARY.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY EVENING)
ISSUED AT 1127 PM MDT FRI JUN 21 2013
VFR EXPECTED ACROSS SE WYOMING THROUGH SAT MORNING. SCTD SHOWERS
AND A FEW STORMS WILL CONTINUE OVER PARTS OF THE PANHANDLE THROUGH
09Z WITH RESIDUAL MOISTURE POSSIBLY PRODUCING SOME SCTD IFR CIGS AFT
09Z UNTIL ABOUT 15Z. SCTD SHOWERS AND STORMS EXPECTED AGAIN SAT
AFTERNOON AND EVENING MAINLY OVER THE PANHANDLE.
&&
.FIRE WEATHER...
ISSUED AT 300 PM MDT FRI JUN 21 2013
DRY AND BREEZY CONDITIONS CONTINUE ALONG AND WEST OF THE LARAMIE
RANGE THIS AFTERNOON. TO THE EAST IN THE PANHANDLE AND UP OVER
NIOBRARA COUNTY...HIGH HUMIDITIES WILL LEAD TO SEVERE
THUNDERSTORMS LATER THIS AFTERNOON AND EVENING. HUMIDITIES OUT
WEST ONCE AGAIN IN THE SINGLE DIGITS WITH WIND GUSTS FROM THE
SOUTHWEST AT 30 TO 35 MPH. WINDS WILL EASE AFTER SUNSET.
CONDITIONS LOOK TO REPEAT FOR SATURDAY AND TO A LESSER EXTENT ON
SUNDAY AFTERNOON. STRONG WINDS WILL CONTINUE NEXT
WEEK...PARTICULARLY MONDAY NIGHT INTO TUESDAY WITH WIND GUSTS
EXCEEDING 40 MPH POSSIBLE OUT WEST.
&&
.CYS WATCHES/WARNINGS/ADVISORIES...
WY...NONE.
NE...NONE.
&&
$$
UPDATE...HAHN
SHORT TERM...CLAYCOMB
LONG TERM...TJT
AVIATION...RE
FIRE WEATHER...CLAYCOMB
AREA FORECAST DISCUSSION
NWS CHEYENNE WY
1025 PM MDT FRI JUN 21 2013
.UPDATE...
ISSUED AT 1025 PM MDT FRI JUN 21 2013
CONVECTION CONTINUES TO WIND DOWN ACROSS THE CWA AS THE
ATMOSPHERE STABILIZES. ALTHOUGH A FEW LIGHT SHOWERS AND EMBEDDED
THUNDERSTORMS WILL STILL BE A POSSIBILITY ACROSS EASTERN AND
NORTHERN ZONES THROUGH THE REST OF THE NIGHT...NO LONGER EXPECT
THE POSSIBILITY OF SEVERE WEATHER. SO...HAVE LET THE SEVERE
THUNDERSTORM WATCH EXPIRE AT 10 PM. INITIAL GLANCE AT 00Z MODEL
DATA CONTINUES TO POINT TO ANOTHER ACTIVE DAY ON SATURDAY. HAHN
&&
.SHORT TERM...(THIS EVENING THROUGH SUNDAY NIGHT)
ISSUED AT 300 PM MDT FRI JUN 21 2013
BELIEVE WE ARE PRIMED FOR A SEVERE WEATHER EPISODE THIS AFTERNOON.
CONDITIONS ARE SET FOR SEVERE THUNDERSTORMS. CHALLENGES ARE WHERE
AND WHEN.
CURRENTLY...STRATUS LAYER ON VISIBLE IMAGERY CONTINUES TO ERODE
ACROSS DAWES AND SIOUX COUNTIES IN THE PANHANDLE AND NIOBRARA
COUNTY IN EAST CENTRAL WYOMING. DEWPOINTS REMAIN EXTREMELY HIGH
(FOR OUR NECK OF THE WOODS)...IN THE PANHANDLE. ALLIANCE STILL
REPORTING A DEW POINT OF 67 DEGREES...WITH LOW TO MID 60S
ELSEWHERE. LATEST STORM PREDICTION CENTER MESOANALYSIS SHOWING
CAPE ALREADY IN MOST OF THE PANHANDLE OF 4500 TO 5000 J/KG. ALL
THAT IS NEEDED IS A LIFTING MECHANISM AND THAT IS DEVELOPING. A
DRY LINE LAYS ACROSS EXTREME SOUTHEASTERN WYOMING...ROUGHLY FROM
JUST EAST OF CHEYENNE TO JUST WEST OF TORRINGTON AND THEN
NORTHWEST TO DOUGLAS. BEHIND THIS LINE...DEWPOINTS HAVE FALLEN
INTO THE 20S. ALONG THIS LINE...SEEING CU DEVELOPING ALONG THE
LINE. HAVE A PRETTY GOOD CELL ALREADY DEVELOPING IN NORTHERN
LARAMIE COUNTY AND SOUTHERN GOSHEN COUNTY. THIS IS MOST LIKELY THE
START OF OUR EVENT. JUST RECEIVED A SWOMCD FROM SPC AT 113 PM STATING
A WATCH IS LIKELY...SO ANOTHER HOUR OR SO...CONVECTION SHOULD
INITIATE.
LATEST HRRR COMPOSITE REFLECTIVITY FORECAST SHOWING THAT CELL IN
SOUTHERN GOSHEN COUNTY TAKING OFF AROUND 3 PM. BY THAT TIME...LOW
STRATUS SHOULD BE MIXED OUT OVER THE NORTHERN PANHANDLE. SUPER CELL
THEN MOVES EAST INTO THE CENTRAL PANHANDLE. WITH SUCH LARGE
CAPE...GOING TO SEE SOME VERY LARGE HAIL REPORTS. NAM/WRF FORECAST
SOUNDINGS CONTINUE TO SHOW STRONGLY VEERING WINDS WITH
NORTHEASTERLY TO EASTERLY SURFACE WINDS AND 35-40KT SOUTHWESTERLY
WINDS AT 700MBS. MORE THAN ENOUGH SHEAR TO SUPPORT SUPERCELLS
CONTINUING INTO THE PANHANDLE. LATEST NAM HELICITIES FOR LATER
THIS AFTERNOON/EVENING SHOWING 150M2/S2...INCREASING TO OVER
300M2/S2 OVER CONVERSE AND NIOBRARA COUNTIES AFTER 00Z...SPREADING
INTO THE NORTHERN PANHANDLE AFTERWARDS. LCLS QUITE LOW UP THERE AS
WELL...SO THE TORNADO THREAT WILL LIKELY BE FROM 23Z THROUGH MAYBE
02 TO 03Z TIME FRAME. SEVERE THUNDERSTORMS COULD LAST WELL INTO THE
EVENING AND OVERNIGHT HOURS IN THE PANHANDLE.
FOR SATURDAY...PRETTY MUCH A REPEAT OF TODAY WITH SEVERE
THUNDERSTORMS OVER EAST CENTRAL WYOMING AND NEBRASKA PANHANDLE.
SHOULD BEGIN TO SEE A DECREASE IN LOW LEVEL MOISTURE SUNDAY AS
WINDS SHIFT TO THE SOUTHWEST. COULD STILL SEE SOME SEVERE
THUNDERSTORMS IN THE PANHANDLE SUNDAY AFTERNOON.
.LONG TERM...(MONDAY THROUGH FRIDAY)
ISSUED AT 300 PM MDT FRI JUN 21 2013
DUE TO THE THREAT OF SEVERE WEATHER THIS AFTERNOON...WILL KEEP
LONG TERM DISCUSSION BRIEF SINCE NOT MUCH HAS CHANGED SINCE
YESTERDAY.
MODELS CONTINUING TO SHOW SOUTHWEST FLOW ALOFT AND RELATIVELY
QUIET WEATHER FOR NEXT WEEK. THERE APPEARS TO BE LITTLE IN THE WAY OF
RAINFALL CHANCES ACROSS SOUTHEAST WYOMING NEXT WEEK...WITH A
SLIGHTLY BETTER CHANCE ACROSS WESTERN NEBRASKA ON MONDAY AHEAD OF
A WEAK COOL FRONT. MODELS SHOW THIS PACIFIC FRONT SLIDING
EASTWARD ACROSS THE NORTHERN ROCKIES MONDAY NIGHT AND INTO
TUESDAY. THE GFS AND THE GEM HAVE TRENDED TOWARDS THE ECMWF
SOLUTION...SHOWING THE FRONT STALLING FURTHER TO THE NORTH AS THE
UPPER LEVEL TROUGH IS FURTHER NORTH AS WELL AND MORE PROGRESSIVE.
THE MAIN IMPACT FROM THIS FRONT WILL BE WINDY CONDITIONS...MAINLY
WEST OF THE LARAMIE RANGE ON MONDAY AND TUESDAY. TEMPERATURES WILL
NOT LOWER MUCH...IF AT ALL...ESPECIALLY FURTHER SOUTH NEAR THE I80
CORRIDOR. THERE APPEARS TO BE A BETTER CHANCE OF TSTORMS AHEAD OF
THIS FRONT ON MONDAY...AS A WEAK SHORTWAVE MOVES NORTHEAST ACROSS
THE HIGH PLAINS. INCREASED POP MONDAY AND MONDAY EVENING MAINLY
ACROSS WESTERN NEBRASKA. AFTER THAT...MODELS ALL INDICATE A STRONG
UPPER LEVEL HIGH DEVELOPING AND INTENSIFYING NEAR THE FOUR
CORNERS REGION BY WEDNESDAY AND THURSDAY. THIS WILL RESULT IN A
PERIOD OF LIGHT WINDS BUT ALSO VERY WARM OR HOT TEMPERATURES
THROUGH LATE NEXT WEEK. WITH THE EXCEPTION OF MONDAY...KEPT POP
BELOW 10 PERCENT THROUGH THE WEEK. HIGH TEMPERATURES WILL CONTINUE
TO BE ABOVE NORMAL AND GENERALLY IN THE 80S AND 90S. THIS UPPER
LEVEL HIGH WILL BEGIN TO DRIFT WESTWARD BY LATE IN THE
WEEK...ALLOWING A CANADIAN COLD FRONT TO PUSH SOUTH. THIS MAY
INCREASE PRECIPITATION AND TSTORM CHANCES BY NEXT WEEKEND DUE
FAVORABLE EASTERLY FLOW BEHIND THE BOUNDARY.
&&
.AVIATION...(FOR THE 00Z TAF ISSUANCE)
VFR CONDITIONS EXPECTED ALONG AND WEST OF INTERSTATE 25 THROUGH
TONIGHT FOR SOUTHEAST WYOMING...ALTHOUGH SOME LOW CIGS MAY DEVELOP
NEAR THE CHEYENNE RIDGE INCLUDING KCYS AFTER 09Z. STRONG TO SEVERE
THUNDERSTORMS WILL CONTINUE EARLY THIS EVENING ACROSS WESTERN
NEBRASKA AND EXTREME EASTERN WYOMING. ERRATIC GUSTY WINDS UP TO 50
MPH...HAIL...AND IFR CONDITIONS HAVE BEEN REPORTED LATE THIS
AFTERNOON...AND MAY CONTINUE WITH THESE THUNDERSTORMS EAST OF A LINE
FROM KIMBALL NEBRASKA TO LUSK WYOMING. THUNDERSTORMS WILL LINGER
THROUGH LATE TONIGHT BEFORE PUSHING EAST OF THE AREA BY MIDNIGHT.
IFR CONDITIONS IN LOW CIGS AND FOG ARE EXPECTED TO RETURN AFTER
MIDNIGHT ACROSS THE HIGH PLAINS OF WESTERN NEBRASKA AND PORTIONS OF
SOUTHEAST WYOMING.
&&
.FIRE WEATHER...
ISSUED AT 300 PM MDT FRI JUN 21 2013
DRY AND BREEZY CONDITIONS CONTINUE ALONG AND WEST OF THE LARAMIE
RANGE THIS AFTERNOON. TO THE EAST IN THE PANHANDLE AND UP OVER
NIOBRARA COUNTY...HIGH HUMIDITIES WILL LEAD TO SEVERE
THUNDERSTORMS LATER THIS AFTERNOON AND EVENING. HUMIDITIES OUT
WEST ONCE AGAIN IN THE SINGLE DIGITS WITH WIND GUSTS FROM THE
SOUTHWEST AT 30 TO 35 MPH. WINDS WILL EASE AFTER SUNSET.
CONDITIONS LOOK TO REPEAT FOR SATURDAY AND TO A LESSER EXTENT ON
SUNDAY AFTERNOON. STRONG WINDS WILL CONTINUE NEXT
WEEK...PARTICULARLY MONDAY NIGHT INTO TUESDAY WITH WIND GUSTS
EXCEEDING 40 MPH POSSIBLE OUT WEST.
&&
.CYS WATCHES/WARNINGS/ADVISORIES...
WY...NONE.
NE...NONE.
&&
$$
UPDATE...HAHN
SHORT TERM...CLAYCOMB
LONG TERM...TJT
AVIATION...TJT
FIRE WEATHER...CLAYCOMB
AREA FORECAST DISCUSSION
NWS GRAND JUNCTION CO
415 AM MDT SAT JUN 22 2013
.SHORT TERM...(TODAY THROUGH SUNDAY)
ISSUED AT 415 AM MDT SAT JUN 22 2013
WEAK OR SHALLOW FRONT IS LOCATED ACROSS MOFFAT/RIO BLANCO COUNTIES
OF NW COLORADO AND NE UTAH. THERE IS SOME (NOT PLENTIFUL) MID
LEVEL MOISTURE STREAMING ACROSS THIS BOUNDARY AS THE RADAR PICKS
UP LOW DBZ RETURNS. VERNAL ASOS HAS STAYED CLR ALL NIGHT...INDICATING
THAT CLOUD BASES ARE ABOVE 12K FEET. TROUGH AXIS OVER THE NRN
INTERMOUNTAIN REGION LIFTS NORTHEAST TOWARD ERN MONTANA/NERN
WYOMING THIS AFTERNOON. SHORT TERM RAP MODEL SHOWS DRIER AIR
SPREADING INTO NE UTAH/NW COLORADO THIS AFTERNOON BEHIND THE
TROUGH AXIS. WHILE THIS IS A REASONABLE SOLUTION...NOT UNUSUAL FOR
AN ISOLATED THUNDERSTORM TO POP OVER THE ERN UINTAS ALONG THE
TRAILING COLD FRONT. GFS40/NAM12 SHOW LOW END CONVECTIVE POTENTIAL
ACROSS THE NRN MOUNTAINS. WILL MAKE A MINOR ADDITION TO THE
FORECAST AND ADD ISOLATED THUNDERSTORMS OVER THE ERN UINTA
MOUNTAINS. OTHERWISE NO CHANGES WITH SOUTHWEST FLOW AND DEEP MIXED
LAYER WILL GENERATE AFTERNOON BREEZES IN THE 20-30 KT
RANGE...ESPECIALLY PARTS OF NW COLORADO.
TONIGHT AND SUNDAY...
THE PERSISTENT SOUTHWEST FLOW THAT HAS BEEN IN PLACE WILL BE
TEMPORARILY DISRUPTED TONIGHT AS A STRONGER PIECE OF ENERGY LIFTS
ACROSS THE NORTHERN ROCKIES INTO THE NORTHERN PLAINS. THIS WILL TURN
THE UPPER FLOW MORE WESTERLY AND HELP PUSH A FRONT INTO THE WESTERN
AND NORTHERN 1/3 OF THE CWA BY MIDNIGHT. WE WILL BE IN THE
SUBSIDENCE PORTION OF THE WAVE OVERNIGHT WHICH SHOULD HELP CLEAR
THINGS OUT AND BRING SLIGHTLY STRONGER INVERSIONS AND COOLER
TEMPERATURES TO MANY PLACES. THE FRONT WILL BE STALLING AND BECOMING
ILL DEFINE BY SUNRISE ON SUNDAY. ALOFT THE SOUTHWESTERLY FLOW WILL
BEGIN TO RE-ESTABLISH ITSELF AS UPSTREAM TROUGHING ONCE AGAIN MOVES
ALONG THE WEST COAST. THERE WILL BE SOME MOISTURE TRAPPED IN THIS
SOUTHWEST FLOW WITH AN ORIGIN ASSOCIATED WITH THE DEEP STREAM OF
HIGH PWATS IN THE NORTHEAST PACIFIC. PWAT PLOTS OVER GJT SHOW THE
NAM MUCH MORE GENEROUS NEAR A HALF OF AN INCH BY PEAK HEATING
SUNDAY...WHILE THE GFS LAGS BELOW A THIRD OF AN INCH. BOTH MODELS
INDICATE SOME WEAK BROAD SCALE ASCENT ASSOCIATED WITH EMBEDDED
ENERGY IN THE FLOW AND THE SUB TROP JET ACROSS THE DESERT SOUTHWEST.
WITH DRY LOW LAYERS THE FOCUS WILL REMAIN ACROSS THE RIDGETOPS WHERE
MOST OF THE ACTION WILL JUST BE BUILDING CU. BETTER MOISTURE GETS
PUSHED UP THE EASTERN DIVIDE IN THE WAKE OF AN FRONT RANGE FRONT. SO
THE BEST CHANCES SEEM TO BE ALONG THE CENTRAL DIVIDE MOUNTAINS WHERE
SMALL POPS WILL BE IN PLACE. TEMPERATURES REMAIN NEAR TO ABOVE
NORMAL.
.LONG TERM...(SUNDAY NIGHT THROUGH FRIDAY)
ISSUED AT 415 AM MDT SAT JUN 22 2013
.SUNDAY NIGHT AND MONDAY...
FORCING QUICKLY WANES SUNDAY NIGHT LEAVING DRY CONDITIONS GOING INTO
MONDAY. THETA SURFACES BEGIN TO SHOW STRONG MOISTURE ADVECTION INTO
THE WEST COAST WHICH WILL GRADUALLY BE PICKED UP BY THE SOUTHWEST
FLOW AND DIRECTED TOWARD OUR CWA. HOWEVER THIS WILL NOT BE UNTIL THE
MID WEEK PERIOD SO MONDAY LOOKS TO AGAIN REMAIN MAINLY PRECIPITATION
FREE. WARM TEMPERATURES AND A BATCH OF MID LEVEL COOLING LOOKS TO
BRING SOME GOOD AFTERNOON MIXING IN THIS WARM AIRMASS. OVERALL THE
GRADIENT NOT QUITE AS STRONG AS THE PAST FEW DAYS BUT AFTERNOON
GUSTY WINDS OVER 25 MPH MAY WIDESPREAD AND BRING ANOTHER ROUND OF
CRITICAL FIRE WEATHER CONDITIONS.
TUESDAY THROUGH FRIDAY...
THE WESTERLIES RETREAT NORTHWARD ON TUESDAY...GUSTY AFTERNOON
WINDS MAY STILL EXIST ACROSS THE NORTH. BUT LESS WIND CAN BE
EXPECTED ACROSS THE SOUTH. FOR WEDENESDAY AND BEYOND...STRONG HIGH
PRESSURE BECOMES ANCHORED OVER THE FOUR CORNER STATES. LESS WIND
BUT TURNING HOTTER ACROSS THE ENTIRE AREA. ISOLATED HIGH BASED
THUNDERSTORMS MAY POP OVER THE COLORADO HIGH COUNTRY...BUT THIS
WILL BE DEPENDENT ON HOW MOISTURE WILL TRAPPED BENEATH THE
SUBTROPICAL HIGH.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SUNDAY MORNING)
ISSUED AT 415 AM MDT SAT JUN 22 2013
AFTERNOON GUSTS OF 25-30KTS ARE EXPECTED OTHERWISE VFR PREVAILS.
THERE IS A 20 PERCENT CHANCE OF AN AFTERNOON -TSRA NORTH OF KVEL.
&&
.FIRE WEATHER...
ISSUED AT 415 AM SAT JUN 22 2013
FIRE ZONE 201 FUELS HAVE BEEN UPGRADED TO CRITICAL...HOWEVER
HUMIDITY VALUES STAY ABOVE RED FLAG CRITERIA. WILL NOT HOIST A RED
FLAG WARNING FOR ZONE 201. FOR THE REMAINDER OF THE AREA...DEEP
MIXED LAYER AND A STRONG JUNE SUN MEANS ANOTHER DAY OF GUSTY WINDS
AT MANY SPOTS.
GUSTY WINDS AND LOW HUMIDITY WILL CONTINUE THROUGH THE REMAINDER
OF THE WEEKEND...THE QUESTION BEING WHETHER THE WINDS WILL SURPASS
CRITICAL CRITERIA ON SUNDAY. WINDS AT THIS POINT LOOK TO DECREASE
UNDER HEADLINE THRESHOLDS THOUGH LOCAL GUSTS ARE EXPECTED IN THE
AFTERNOON.
ON MONDAY...NEGATIVELY TILTED TROUGH SWIPES NORTHERN REGION OF CWA
AND MAY INCREASE WINDS DURING THE DAY. WILL BE MONITORING THIS
THROUGH THE WEEKEND.
TEMPERATURES LATE NEXT WEEK ASSOCIATED WITH THE BUILDING RIDGE
WILL INCREASE WELL ABOVE NORMAL.
&&
.GJT WATCHES/WARNINGS/ADVISORIES...
CO...RED FLAG WARNING FROM NOON TODAY TO 9 PM MDT THIS EVENING FOR
COZ200-202-203-207-290>293.
UT...RED FLAG WARNING FROM NOON TODAY TO 9 PM MDT THIS EVENING FOR
UTZ486-487.
&&
$$
SHORT TERM...PF/15
LONG TERM...15/PF
AVIATION...PF
FIRE WEATHER...CC
AREA FORECAST DISCUSSION
NWS MIAMI FL
1044 AM EDT SAT JUN 22 2013
.UPDATE...
FORECAST WAS UPDATED FOR THE SHORT TERM AND THE REMAINDER OF THE
WEEKEND. LATEST GUIDANCE SUGGESTS THAT FOR TODAY MAINLY ISOLATED
SHOWERS OR ISOLATED THUNDERSTORMS EXPECTED ACROSS THE ATLANTIC
WATERS AND EASTERN HALF OF THE PENINSULA WHILE FOR THE WESTERN
HALF THIS AFTERNOON MORE SCATTERED SHOWER AND THUNDERSTORM
ACTIVITY IS EXPECTED. THE FORECAST WAS ALSO UPDATED TO REFLECT A
CHANCE OF CONVECTION TONIGHT ACROSS THE ATLANTIC WATERS AND THE
EASTERN THIRD OF THE PENINSULA AS A LOW LEVEL TROUGH CONTINUES
TO MOVE WESTWARD ACROSS THE NORTHWEST BAHAMAS AND INTO THE LOCAL
ATLANTIC WATERS. THE LOW LEVEL TROUGH IS FORECAST TO REMAIN MOVING
WESTWARD ACROSS THE REGION TONIGHT THROUGH SUNDAY WITH A CHANCE
OF SHOWERS AND THUNDERSTORMS THROUGH THAT PERIOD.
60
&&
.PREV DISCUSSION... /ISSUED 648 AM EDT SAT JUN 22 2013/
AVIATION...
QUIET WEATHER IS EXPECTED FOR THE TAF PERIOD WITH VFR CONDITIONS
PREVAILING. THERE IS SOME TROPICAL MOISTURE TRYING TO MAKE ITS WAY
INTO SOUTH FLORIDA, BUT IS HAVING TROUBLE DUE TO THE DRY AIR IN
PLACE IN THE UPPER LEVELS. THERE IS STILL A SLIGHT CHANCE OF A
SHOWER OR A THUNDERSTORM TODAY, BUT TOO UNCERTAIN TO MAKE ANY
REFERENCE IN THE TAFS AT THIS TIME.
PREV DISCUSSION... /ISSUED 256 AM EDT SAT JUN 22 2013/
SHORT TERM (TODAY THROUGH MONDAY)...
DEEP LAYER RIDGE IS BEGINNING TO SHIFT NORTH AND THE 00Z MFL
SOUNDING WAS SHOWING A DEEP EASTERLY FLOW AT 5 TO 10 KNOTS. THE
TROPICAL WAVE THAT WAS PRODUCING NUMEROUS SHOWERS AND SOME
THUNDERSTORMS A FEW DAYS AGO HAS BEEN FIGHTING SOME DRY AIR THAT
SURROUNDS IT AND HAS NOW MOVED INTO THE CENTRAL CARIBBEAN LOSING MOST
OF ITS CONVECTION. THE NORTHERN PORTION OF THE WAVE HAS BECOME A
TROUGH OVER THE CENTRAL BAHAMAS AND HAS SCATTERED SHOWERS AND FEW
THUNDERSTORMS ASSOCIATED WITH IT. THE TROUGH HAS SLOWED ITS
FORWARD MOVEMENT AND MUCH DRIER AIR ALOFT IS AHEAD OF IT ACROSS
THE WESTERN BAHAMAS AND SOUTH FLORIDA. IN FACT, THE SOUNDING LAST
EVENING SHOWED THE PWAT HAD LOWERED TO 1.13 INCHES WHICH IS BELOW
THE 25TH PERCENTILE FOR MID-LATE JUNE AND THERE WERE ONLY A FEW
STORMS LATE YESTERDAY AS A RESULT OF THIS DRY AIR INTRUSION. DUE TO
THE FACT THE ACTUAL WAVE WILL NOW REMAIN WELL TO OUR SOUTH AND THE
TROUGH AXIS HAS SLOWED, THE HRRR IS SHOWING VIRTUALLY NO ACTION
ALONG THE EAST COAST TODAY AND WITH THE DEEP EAST TO WEST STEERING
FLOW DEPICTS SHOWERS AND STORMS DEVELOPING WELL INLAND AFTER 18Z
AND THEN INCREASING AS THEY MOVE TOWARDS THE COLLIER COUNTY COAST
AND THE LAKE REGION. THEREFORE, WILL LOWER THE POPS TO A SILENT 10
PERCENT OVER THE EAST METRO REGION AND TREND UP TO LOW END
SCATTERED FARTHER INLAND. ALL OF THE GLOBAL MODELS ARE IN GOOD
AGREEMENT WITH THIS SCENARIO AND ALSO INCREASE MOISTURE ON SUNDAY
AS THE TROUGH AXIS APPROACHES. THE MOISTURE WILL STILL BE AROUND
ON MONDAY BUT MODEL FORECAST SOUNDINGS ONLY SHOW AN INCREASE IN
PWAT TO NEAR AVERAGE FOR THIS TIME OF YEAR SO SIGNIFICANT RAINFALL
IS NOT ANTICIPATED.
LONG TERM (MONDAY NIGHT THROUGH FRIDAY)...
THE DEEP LAYER RIDGE WILL BECOME NEARLY STATIONARY ACROSS NORTH
FLORIDA FOR MUCH OF THE UPCOMING WEEK SO THE BEST CHANCES FOR RAIN
WILL BE DURING THE LATE NIGHT AND EARLY MORNING ALONG THE EAST
COAST AND IN THE AFTERNOON TO EARLY EVENING FOR THE INTERIOR AND
SOUTHWEST COAST. MOISTURE INCREASE WILL AGAIN NOT BE PLENTIFUL SO
ONLY ISOLATED AREAS OF HEAVIER RAIN CAN BE EXPECTED MAINLY WHERE
THE AFTERNOON THUNDERSTORMS CAN DEVELOP.
MARINE...
WIND SPEEDS WILL FLUCTUATE THROUGH THE PERIOD BUT REMAIN IN AN
EAST TO SOUTHEAST DIRECTION SO SEAS WILL BE AT 4 FEET OR LESS.
FIRE WEATHER...
NO PROBLEMS OR CONCERNS WITH AMPLE LOW LEVEL MOISTURE REMAINING IN PLACE.
&&
.PRELIMINARY POINT TEMPS/POPS...
WEST PALM BEACH 78 88 78 88 / 30 40 20 30
FORT LAUDERDALE 79 88 80 88 / 30 40 20 20
MIAMI 78 88 79 89 / 30 40 20 20
NAPLES 74 92 75 92 / 30 50 20 40
&&
.MFL WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
AM...NONE.
GM...NONE.
&&
$$
DISCUSSION/MARINE/FIRE...60/BD
AVIATION/RADAR...57/DG
AREA FORECAST DISCUSSION
NWS MIAMI FL
648 AM EDT SAT JUN 22 2013
.AVIATION...
QUIET WEATHER IS EXPECTED FOR THE TAF PERIOD WITH VFR CONDITIONS
PREVAILING. THERE IS SOME TROPICAL MOISTURE TRYING TO MAKE ITS WAY
INTO SOUTH FLORIDA, BUT IS HAVING TROUBLE DUE TO THE DRY AIR IN
PLACE IN THE UPPER LEVELS. THERE IS STILL A SLIGHT CHANCE OF A
SHOWER OR A THUNDERSTORM TODAY, BUT TOO UNCERTAIN TO MAKE ANY
REFERENCE IN THE TAFS AT THIS TIME.
&&
.PREV DISCUSSION... /ISSUED 256 AM EDT SAT JUN 22 2013/
SHORT TERM (TODAY THROUGH MONDAY)...
DEEP LAYER RIDGE IS BEGINNING TO SHIFT NORTH AND THE 00Z MFL
SOUNDING WAS SHOWING A DEEP EASTERLY FLOW AT 5 TO 10 KNOTS. THE
TROPICAL WAVE THAT WAS PRODUCING NUMEROUS SHOWERS AND SOME
THUNDERSTORMS A FEW DAYS AGO HAS BEEN FIGHTING SOME DRY AIR THAT
SURROUNDS IT AND HAS NOW MOVED INTO THE CENTRAL CARIBBEAN LOSING MOST
OF ITS CONVECTION. THE NORTHERN PORTION OF THE WAVE HAS BECOME A
TROUGH OVER THE CENTRAL BAHAMAS AND HAS SCATTERED SHOWERS AND FEW
THUNDERSTORMS ASSOCIATED WITH IT. THE TROUGH HAS SLOWED ITS
FORWARD MOVEMENT AND MUCH DRIER AIR ALOFT IS AHEAD OF IT ACROSS
THE WESTERN BAHAMAS AND SOUTH FLORIDA. IN FACT, THE SOUNDING LAST
EVENING SHOWED THE PWAT HAD LOWERED TO 1.13 INCHES WHICH IS BELOW
THE 25TH PERCENTILE FOR MID-LATE JUNE AND THERE WERE ONLY A FEW
STORMS LATE YESTERDAY AS A RESULT OF THIS DRY AIR INTRUSION. DUE TO
THE FACT THE ACTUAL WAVE WILL NOW REMAIN WELL TO OUR SOUTH AND THE
TROUGH AXIS HAS SLOWED, THE HRRR IS SHOWING VIRTUALLY NO ACTION
ALONG THE EAST COAST TODAY AND WITH THE DEEP EAST TO WEST STEERING
FLOW DEPICTS SHOWERS AND STORMS DEVELOPING WELL INLAND AFTER 18Z
AND THEN INCREASING AS THEY MOVE TOWARDS THE COLLIER COUNTY COAST
AND THE LAKE REGION. THEREFORE, WILL LOWER THE POPS TO A SILENT 10
PERCENT OVER THE EAST METRO REGION AND TREND UP TO LOW END
SCATTERED FARTHER INLAND. ALL OF THE GLOBAL MODELS ARE IN GOOD
AGREEMENT WITH THIS SCENARIO AND ALSO INCREASE MOISTURE ON SUNDAY
AS THE TROUGH AXIS APPROACHES. THE MOISTURE WILL STILL BE AROUND
ON MONDAY BUT MODEL FORECAST SOUNDINGS ONLY SHOW AN INCREASE IN
PWAT TO NEAR AVERAGE FOR THIS TIME OF YEAR SO SIGNIFICANT RAINFALL
IS NOT ANTICIPATED.
LONG TERM (MONDAY NIGHT THROUGH FRIDAY)...
THE DEEP LAYER RIDGE WILL BECOME NEARLY STATIONARY ACROSS NORTH
FLORIDA FOR MUCH OF THE UPCOMING WEEK SO THE BEST CHANCES FOR RAIN
WILL BE DURING THE LATE NIGHT AND EARLY MORNING ALONG THE EAST
COAST AND IN THE AFTERNOON TO EARLY EVENING FOR THE INTERIOR AND
SOUTHWEST COAST. MOISTURE INCREASE WILL AGAIN NOT BE PLENTIFUL SO
ONLY ISOLATED AREAS OF HEAVIER RAIN CAN BE EXPECTED MAINLY WHERE
THE AFTERNOON THUNDERSTORMS CAN DEVELOP.
MARINE...
WIND SPEEDS WILL FLUCTUATE THROUGH THE PERIOD BUT REMAIN IN AN
EAST TO SOUTHEAST DIRECTION SO SEAS WILL BE AT 4 FEET OR LESS.
FIRE WEATHER...
NO PROBLEMS OR CONCERNS WITH AMPLE LOW LEVEL MOISTURE REMAINING IN PLACE.
&&
.PRELIMINARY POINT TEMPS/POPS...
WEST PALM BEACH 89 78 88 78 / 10 20 20 20
FORT LAUDERDALE 88 79 88 80 / 10 20 20 20
MIAMI 89 78 88 79 / 10 20 20 20
NAPLES 92 74 92 75 / 30 20 20 20
&&
.MFL WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
AM...NONE.
GM...NONE.
&&
$$
DISCUSSION/MARINE/FIRE...30/KOB
AVIATION/RADAR...13/SI
AREA FORECAST DISCUSSION
NWS LINCOLN IL
1044 AM CDT SAT JUN 22 2013
.DISCUSSION...
ISSUED 1044 AM CDT SAT JUN 22 2013
CONVECTIVE CHANCES REMAIN MAIN CONCERN TODAY. PRIMARY OUTFLOW
BOUNDARY IS CURRENTLY PUSHING SOUTH INTO THE NORTHEAST CWA WITH
SCATTERED THUNDERSTORMS DEVELOPING BEHIND THIS FEATURE. THIS
SHOULD CONTINUE INTO EARLY AFTERNOON AS THE BOUNDARY SLIPS
SOUTH...HOWEVER IT SHOULD EVENTUALLY SLOW AND STALL /UNLESS MORE
VIGOROUS CONVECTION KEEPS COLD POOL GOING/ AS IT ENCOUNTERS 10-20
KT SOUTHWEST SYNOPTIC FLOW. SCATTERED SHOWERS AND SPRINKLES
AFFECTING PARTS OF THE WESTERN CWA OUT OF A MID LEVEL DECK AND
FEEL THIS AREA COULD FILL IN WITH SCATTERED TSTMS WITH DAYTIME
HEATING. 12Z ILX SOUNDING SHOWED HIGH CAPES AND VERY WEAK WINDS
ALOFT...WHICH COMBINED WITH A 2 INCH P/W MAKES HEAVY RAIN RATES
AND FREQUENT LIGHTNING MAIN THREATS WITH STORMS TODAY. ISOLATED
PULSE TYPE NEAR SVR POSSIBLE DUE TO PRECIP LOADING BUT LOW BULK
SHEAR MAKES MORE ORGANIZED SVR UNLIKELY. HAVE INCREASED POPS TO LOW
CHANCE OVER MOST OF THE CWA WITH LIKELY POPS IN THE NE CWA WHERE
MORE SIGNIFICANT OUTFLOW BOUNDARY SHIFTS THROUGH NEXT FEW HOURS.
SUNNIER LOCATIONS SHOULD GET INTO THE LOWER 90S AND WITH DEWPOINTS
IN THE LOWER 70S PEAK HEAT INDICES NEAR 100 POSSIBLE.
25
&&
.AVIATION...
ISSUED 520 AM CDT SAT JUN 22 2013
COVERAGE OF TSRA AND THE AFFECTS ON CIGS/VSBYS THIS FORECAST PERIOD.
MID LEVEL MOISTURE HAS RAPIDLY DEVELOPED ACRS THE AREA THIS MORNING
IN ADVANCE OF A WEAK UPPER LEVEL DISTURBANCE COUPLED WITH SOME
ELEVATED INSTABILITY. JUST HOW MUCH SHOWER DEVELOPMENT TAKES PLACE
IS STILL IN QUESTION AHEAD OF THIS SYSTEM...BUT WILL COVER FOR NOW
WITH VCTS AND CONTINUE TO TRY TO PIN DOWN SOME BETTER TIMING OF
STORMS IN THE AFTN HOURS. STILL APPEARS THE COVERAGE SHOULD QUICKLY
DIMINISH JUST AFTR SUNSET THIS EVENING WITH MAIN MID AND HIGH LEVEL
MOISTURE REMAINING TONIGHT. IF SKIES SHOULD CLEAR OUT LATER TONIGHT
WE MAY HAVE TO DEAL WITH SOME PATCHY GROUND FOG...BUT FOR NOW WILL
LEAVE OUT OF TAFS. SFC WINDS WILL REMAIN OUT OF A SSW (180-210)
DIRECTION THRU THIS FORECAST PERIOD. SPEEDS WILL RANGE FROM 10 TO
15 KTS TODAY WITH A FEW GUSTS IN THE 15 TO 20 KT RANGE AND THEN
DIMINISH TO AROUND 10 KTS THIS EVENING.
SMITH
&&
.PREV DISCUSSION...
ISSUED 250 AM CDT SAT JUN 22 2013
2 AM SATELLITE IMAGERY AND RADAR DATA SHOWING A PAIR OF MCS
SYSTEMS MERGING FROM SOUTH DAKOTA EASTWARD INTO SOUTHERN
WISCONSIN. EASTERN END OF THE LINE OF STORMS HAS MADE A SOUTHWARD
PUSH INTO NORTHEAST ILLINOIS...WITH THIS PART OF THE MCS BECOMING
THE DOMINANT ONE AS LIGHTNING DIMINISHES OVER SOUTHERN MINNESOTA.
LINGERING BOUNDARY FROM THE STORMS IN OUR AREA YESTERDAY WRAPS
AROUND THE SOUTHWEST AND SOUTHEAST PARTS OF THE FORECAST AREA.
STILL SEEING A FEW SPRINKLES IN THE FAR SOUTHEAST CWA WITH THIS
BOUNDARY.
FORECAST CHALLENGES FOR THIS PACKAGE GENERALLY REVOLVE AROUND
TIMING OF THUNDERSTORM CHANCES...AS WELL AS THE ONGOING HEAT AND
HUMIDITY.
SHORT TERM...TODAY THROUGH MONDAY...
MODELS ARE STRUGGLING TO GET A HANDLE ON THE CURRENT SITUATION...
WITH THE HRRR AND THE REGIONAL CANADIAN MODEL CLOSEST TO REALITY.
NEITHER OF THESE MODELS SHOW THE STORMS MAKING IT AS FAR SOUTH AS
OUR FORECAST AREA...BUT AS THE MCS FROM YESTERDAY SHOWED...THAT
OUTCOME IS DEFINITELY NOT GUARANTEED. WILL INCLUDE SOME ISOLATED
THUNDERSTORM MENTION IN THE NORTHEAST THIRD OF THE CWA THIS
MORNING...BETWEEN THIS LINE AND POTENTIALLY SOME DEVELOPMENT ALONG
THE OUTFLOW BOUNDARY...WITH AROUND 30 PERCENT CHANCES ACROSS THE
NORTHEAST DURING THE AFTERNOON. HAVE MENTIONED ISOLATED STORMS
ELSEWHERE THIS AFTERNOON AND EARLY EVENING.
FOCUS CONTINUES TO BE WITH TIMING OF VARIOUS MCS FEATURES THIS
WEEKEND. DEVELOPMENT ACROSS IOWA/MINNESOTA ON SUNDAY EXPECTED TO
EXTEND SOUTHWEST INTO MISSOURI...BUT ONLY THE NAM BRINGS ANY OF IT
THIS FAR EAST BY MONDAY MORNING. HAVE LIMITED ANY 30 PERCENT OR
HIGHER POPS TO THE FAR NORTHWEST LATE SUNDAY NIGHT... WITH MORE
WIDESPREAD CHANCES MONDAY. THE ECMWF AND CANADIAN MODELS SHOW THE
MCS SPREADING OVER THE FORECAST AREA... WHILE THE NAM AND GFS
SHUNT IT MORE TO THE NORTHEAST. SEVERE WEATHER POTENTIAL APPEARS
TO INCREASE BY MONDAY...MAINLY IN THE NORTHWEST CWA.
HAVE KEPT HIGH TEMPERATURES RIGHT AROUND 90 DEGREES FOR THE NEXT
FEW DAYS...WITH HEAT INDEX VALUES IN THE MID TO UPPER 90S. WILL
HAVE TO KEEP AN EYE ON HIGHS FOR MONDAY THOUGH...AS THEY COULD BE
LOWER IF THIS MCS DOES PAN OUT.
LONG TERM...TUESDAY THROUGH FRIDAY...
BROAD EAST-WEST RIDGE EXPECTED TO COVER THE SOUTH HALF OF THE
CONUS MUCH OF THE WEEK...WITH THE MAIN STORM TRACK ACROSS THE
NORTHERN STATES. MCS TRACKS REMAINS THE CONCERN AND ALTHOUGH MANY
OF THEM ARE FURTHER NORTH...LEFTOVER OUTFLOWS MAKE IT DIFFICULT TO
PIN DOWN ANY DRY PERIODS WITH ANY CERTAINTY. HIGHEST POPS FROM
WEDNESDAY NIGHT TO FRIDAY ARE TIED INTO PASSAGE OF A COLD FRONT...
WHICH MAY TAKE UNTIL EARLY FRIDAY TO FULLY PASS THE REGION AS THE
UPPER RIDGING BUILDS ACROSS THE ROCKIES AND PUTS THE MIDWEST MORE
OF A TROUGH. THIS PARTICULAR PATTERN WOULD SHOW THE HEAT FINALLY
BREAKING ON FRIDAY...WITH COOLER CONDITIONS NEXT WEEKEND.
GEELHART
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS LINCOLN IL
523 AM CDT SAT JUN 22 2013
.DISCUSSION...
ISSUED 250 AM CDT SAT JUN 22 2013
2 AM SATELLITE IMAGERY AND RADAR DATA SHOWING A PAIR OF MCS
SYSTEMS MERGING FROM SOUTH DAKOTA EASTWARD INTO SOUTHERN
WISCONSIN. EASTERN END OF THE LINE OF STORMS HAS MADE A SOUTHWARD
PUSH INTO NORTHEAST ILLINOIS...WITH THIS PART OF THE MCS BECOMING
THE DOMINANT ONE AS LIGHTNING DIMINISHES OVER SOUTHERN MINNESOTA.
LINGERING BOUNDARY FROM THE STORMS IN OUR AREA YESTERDAY WRAPS
AROUND THE SOUTHWEST AND SOUTHEAST PARTS OF THE FORECAST AREA.
STILL SEEING A FEW SPRINKLES IN THE FAR SOUTHEAST CWA WITH THIS
BOUNDARY.
FORECAST CHALLENGES FOR THIS PACKAGE GENERALLY REVOLVE AROUND
TIMING OF THUNDERSTORM CHANCES...AS WELL AS THE ONGOING HEAT AND
HUMIDITY.
SHORT TERM...TODAY THROUGH MONDAY...
MODELS ARE STRUGGLING TO GET A HANDLE ON THE CURRENT SITUATION...
WITH THE HRRR AND THE REGIONAL CANADIAN MODEL CLOSEST TO REALITY.
NEITHER OF THESE MODELS SHOW THE STORMS MAKING IT AS FAR SOUTH AS
OUR FORECAST AREA...BUT AS THE MCS FROM YESTERDAY SHOWED...THAT
OUTCOME IS DEFINITELY NOT GUARANTEED. WILL INCLUDE SOME ISOLATED
THUNDERSTORM MENTION IN THE NORTHEAST THIRD OF THE CWA THIS
MORNING...BETWEEN THIS LINE AND POTENTIALLY SOME DEVELOPMENT ALONG
THE OUTFLOW BOUNDARY...WITH AROUND 30 PERCENT CHANCES ACROSS THE
NORTHEAST DURING THE AFTERNOON. HAVE MENTIONED ISOLATED STORMS
ELSEWHERE THIS AFTERNOON AND EARLY EVENING.
FOCUS CONTINUES TO BE WITH TIMING OF VARIOUS MCS FEATURES THIS
WEEKEND. DEVELOPMENT ACROSS IOWA/MINNESOTA ON SUNDAY EXPECTED TO
EXTEND SOUTHWEST INTO MISSOURI...BUT ONLY THE NAM BRINGS ANY OF IT
THIS FAR EAST BY MONDAY MORNING. HAVE LIMITED ANY 30 PERCENT OR
HIGHER POPS TO THE FAR NORTHWEST LATE SUNDAY NIGHT... WITH MORE
WIDESPREAD CHANCES MONDAY. THE ECMWF AND CANADIAN MODELS SHOW THE
MCS SPREADING OVER THE FORECAST AREA... WHILE THE NAM AND GFS
SHUNT IT MORE TO THE NORTHEAST. SEVERE WEATHER POTENTIAL APPEARS
TO INCREASE BY MONDAY...MAINLY IN THE NORTHWEST CWA.
HAVE KEPT HIGH TEMPERATURES RIGHT AROUND 90 DEGREES FOR THE NEXT
FEW DAYS...WITH HEAT INDEX VALUES IN THE MID TO UPPER 90S. WILL
HAVE TO KEEP AN EYE ON HIGHS FOR MONDAY THOUGH...AS THEY COULD BE
LOWER IF THIS MCS DOES PAN OUT.
LONG TERM...TUESDAY THROUGH FRIDAY...
BROAD EAST-WEST RIDGE EXPECTED TO COVER THE SOUTH HALF OF THE
CONUS MUCH OF THE WEEK...WITH THE MAIN STORM TRACK ACROSS THE
NORTHERN STATES. MCS TRACKS REMAINS THE CONCERN AND ALTHOUGH MANY
OF THEM ARE FURTHER NORTH...LEFTOVER OUTFLOWS MAKE IT DIFFICULT TO
PIN DOWN ANY DRY PERIODS WITH ANY CERTAINTY. HIGHEST POPS FROM
WEDNESDAY NIGHT TO FRIDAY ARE TIED INTO PASSAGE OF A COLD FRONT...
WHICH MAY TAKE UNTIL EARLY FRIDAY TO FULLY PASS THE REGION AS THE
UPPER RIDGING BUILDS ACROSS THE ROCKIES AND PUTS THE MIDWEST MORE
OF A TROUGH. THIS PARTICULAR PATTERN WOULD SHOW THE HEAT FINALLY
BREAKING ON FRIDAY...WITH COOLER CONDITIONS NEXT WEEKEND.
GEELHART
&&
.AVIATION...
ISSUED 520 AM CDT SAT JUN 22 2013
COVERAGE OF TSRA AND THE AFFECTS ON CIGS/VSBYS THIS FORECAST PERIOD.
MID LEVEL MOISTURE HAS RAPIDLY DEVELOPED ACRS THE AREA THIS MORNING
IN ADVANCE OF A WEAK UPPER LEVEL DISTURBANCE COUPLED WITH SOME
ELEVATED INSTABILITY. JUST HOW MUCH SHOWER DEVELOPMENT TAKES PLACE
IS STILL IN QUESTION AHEAD OF THIS SYSTEM...BUT WILL COVER FOR NOW
WITH VCTS AND CONTINUE TO TRY TO PIN DOWN SOME BETTER TIMING OF
STORMS IN THE AFTN HOURS. STILL APPEARS THE COVERAGE SHOULD QUICKLY
DIMINISH JUST AFTR SUNSET THIS EVENING WITH MAIN MID AND HIGH LEVEL
MOISTURE REMAINING TONIGHT. IF SKIES SHOULD CLEAR OUT LATER TONIGHT
WE MAY HAVE TO DEAL WITH SOME PATCHY GROUND FOG...BUT FOR NOW WILL
LEAVE OUT OF TAFS. SFC WINDS WILL REMAIN OUT OF A SSW (180-210)
DIRECTION THRU THIS FORECAST PERIOD. SPEEDS WILL RANGE FROM 10 TO
15 KTS TODAY WITH A FEW GUSTS IN THE 15 TO 20 KT RANGE AND THEN
DIMINISH TO AROUND 10 KTS THIS EVENING.
SMITH
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS TOPEKA KS
618 AM CDT SAT JUN 22 2013
UPDATED FOR AVIATION.
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 343 AM CDT SAT JUN 22 2013
LARGE COMPLEX OF RAIN AND THUNDERSTORMS CONTINUES TO MARCH EASTWARD
ACROSS MUCH OF NORTH AND EAST NEBRASKA AND POINTS NE. SOUTHERN
PROGRESS OF THE OUTFLOW HAS SLOWED SOMEWHAT THE PAST HOUR OR SO.
SHORTWAVE TROF NOTED IN WV IMAGERY OVER EASTERN KS ATTM...BUT IS
PRODUCING ONLY CLOUDS SO FAR AS IT PASSES. EVENING SOUNDING AT TOP
SHOWED STEEP LAPSE RATES IN THE 750 TO 550 MB LAYER...HOWEVER CAP IS
STRONG BELOW 700MB AND COLUMN IS DRY THROUGH ABOUT 400MB. ONLY
GUIDANCE THAT SUGGESTS PRECIP THIS MORNING HAS BEEN OUT WEST WITH
THE HRRR FOR SEVERAL RUNS...ALL OTHERS REMAIN DRY. WILL CARRY A
SILENT POP WEST OF MANHATTAN FOR A FEW HOURS THIS MORNING. COULD
GET A BRIEF BREAK NORTH FROM SOME OF THE OUTFLOW FROM THE
NORTH...BUT EXPECT THAT WOULD BE SHORT LIVED. HIGHS STILL EXPECTED
INTO THE LOWER TO MIDDLE 90S WITH HEAT INDICES RUNNING AROUND 100
ALONG THE KS RIVER VALLEY. WINDS BECOME QUITE BREEZY OUT OF THE
SOUTH AS YOU GO WESTWARD...WITH SUSTAINED AFTERNOON WINDS AROUND 30
WITH GUSTS 35-40 POSSIBLE. WILL MONITOR TRENDS FOR WIND ADVISORY
BUT IS BORDERLINE AT THIS TIME. OVERNIGHT LOWS EXPECTED ON THE WARM
SIDE AGAIN IN THE MIDDLE 70S. 67
.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 343 AM CDT SAT JUN 22 2013
MID RANGE AND EXTENDED FORECAST (SUNDAY THROUGH FRIDAY)...
VERY LITTLE CHANGE IN THIS FORECAST PACKAGE AS MODELS ARE STILL
CONSISTENT IN SHOWING A LARGE SCALE RIDGING PATTERN ACROSS THE
SOUTHEASTERN PORTION OF THE CONUS THROUGH THE WEEKEND...WITH A
PACIFIC TROUGH OVER THE WEST COAST. LIGHT SOUTHWEST FLOW WILL BE
PRESENT OVER THE ROCKY MOUNTAINS UP THROUGH THE NORTHERN
PLAINS...WITH THE CENTRAL PLAINS BEING ON THE EASTERN FRINGE OF THE
BETTER FLOW. EXPECT WARM TEMPERATURES TO CONTINUE FOR SUNDAY...WITH
A PRETTY DECENT CHANCE FOR RAIN SUNDAY NIGHT AS A DISTURBANCE WITHIN
THE SOUTHWESTERLY FLOW ALOFT WILL TRIGGER A ROUND OF THUNDERSTORMS
ACROSS SOUTHERN NEBRASKA AND NORTHERN KANSAS. THE BEST CHANCE FOR
RAIN WILL BE ALONG THE KS/NE BORDER...WITH DECREASING CHANCES
FURTHER SOUTH ALONG INTERSTATE 70.
EXPECT LITTLE IN THE WAY OF CONVECTIVE CHANCES AFTER THE SUNDAY
NIGHT ROUND OF THUNDERSTORMS. ECMWF HAS BEEN CONSISTENT IN
PREDICTING THE FOUR CORNERS MID LEVEL RIDGE TO SET UP BY MID
WEEK...WHICH WILL KEEP TEMPERATURES IN THE AREA WARM THROUGH THE
EXTENDED PERIOD. TEMPERATURES GENERALLY WILL REMAIN IN THE LOWER TO
MID 90S ACROSS EASTERN KANSAS THROUGH THE EXTENDED PERIOD...WITH
TEMPS REACHING THE MID TO UPPER 90S IN WESTERN KANSAS. THE NEXT
CHANCES FOR RAIN WILL BE RATHER MINIMAL AS A BOUNDARY LOOKS TO SLIDE
INTO THE AREA IN THE THURSDAY/FRIDAY TIME FRAME. THIS BOUNDARY WOULD
BE THE FOCUS FOR ANY POTENTIAL CONVECTION DURING THAT TIME PERIOD.
MADE VIRTUALLY NO CHANGE TO THE FORECAST FOR THE LATE PART OF THE
WEEK FOR THESE POTENTIAL SHOWERS.
JL
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SUNDAY MORNING)
ISSUED AT 616 AM CDT SAT JUN 22 2013
VFR CONDITIONS EXPECTED FOR THE PERIOD. SOUTHERLY WINDS INCREASE
THROUGHOUT THE DAY. CLOUDS GENERALLY AOA 15KFT...WITH NEXT CHANCE
FOR THUNDERSTORMS TOWARD THE NEBRASKA BORDER LATE IN THE PERIOD. 67
&&
.TOP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...CRAVEN
LONG TERM...LEIGHTON
AVIATION...67
AREA FORECAST DISCUSSION
NWS WAKEFIELD VA
724 AM EDT SAT JUN 22 2013
.SYNOPSIS...
A WEAK AREA OF LOW PRESSURE WILL LINGER ALONG THE NORTH CAROLINA
COAST THROUGH TODAY. HIGH PRESSURE WILL BE ANCHORED OFF THE MID
ATLANTIC COAST SUNDAY THROUGH THE MIDDLE OF NEXT WEEK.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
INTERESTING FORECAST CHALLENGES TODAY. HAVE CONVECTION DEVELOPING
ALONG A COASTAL FRONT OVER NORTH CAROLINA AND SLOWLY MOVING NORTH.
THIS IS ASSOCIATED WITH A WEAK PV MAX ALOFT AND CAN BE SEEN ON
WATER VAPOR. MEANWHILE HAVE A WEAK RIDGE OF HIGH PRESSURE ALOFT
JUST TO THE NORTH OF THIS FEATURE. THIS HIGH IS SLOWLY WEAKENING
AND MOVING TO THE EAST. THIS WILL ALLOW THE WEAK TROF TO LIFT
NORTH TODAY. CAN SEE WINDS BECOMING MORE SOUTHEAST ALOFT ON VWP
OBSERVATIONS AROUND THE AREA. THIS WILL ADVECT PLENTY OF MOISTURE
INTO THE SOUTHERN PART OF THE CWA TODAY. WILL FOLLOW THE HRRR IDEA
OF MOVING THE PRECIPITATION FROM NORTH CAROLINA INTO SOUTHEAST
VIRGINIA DURING THE MORNING. COULD SEE SOME BRIEF HEAVY RAIN WITH
SOME OF THE SHOWERS. BY THIS AFTERNOON THE MOISTURE WILL BE PULLED
NORTH OVER MOST OF THE CWA. HOWEVER THE UPPER TROF WILL BE
WEAKENING AND THIS WILL CAUSE THE PRECIPITATION TO MORE SCATTERED.
THIS FOLLOWS THE NAM AND GFS. ALSO THE SREF SHOWS THE BEST CHANCES
FOR PRECIP MOVING TO THE WESTERN SECTIONS OF THE CWA DURING THE
AFTERNOON AND EVENING. SINCE WESTERN AREAS WILL BE SLOWER TO CLOUD
UP WILL HAVE SOME MORE CAPE TO AIDE IN THUNDERSTORM DEVELOPMENT.
AGAIN WITH PLENTY OF MOISTURE AROUND COULD SEE SOME BRIEF HEAVY
DOWNPOURS. TEMPERATURES WILL BE DEPENDENT ON THE AMOUNT OF CLOUD
COVER TODAY. EXPECT TO KEEP MAXES AROUND 80 SOUTHEAST BUT REACH
THE MID 80S ACROSS WESTERN SECTIONS. AGAIN THIS IS CLOSE TO MOS GUIDE.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH MONDAY/...
A SECOND UPPER LOW OVER GEORGIA TODAY WILL SLOWLY LIFT NORTH LATE
TONIGHT AND MOVE ACROSS TO THE WEST OF THE AREA ON SUNDAY. THE
UPPER LOW AGAIN WILL BE WEAKENING AS IT MERGES WITH THE WESTERLY
TO THE NORTH. THIS THIS WILL HELP TO KEEP BEST CHANCES OF SHOWERS
AND THUNDERSTORMS IN THE WESTERN AREAS TONIGHT AND SATURDAY. WITH
THE HIGH PRESSURE CENTERED OFF THE MID ATLANTIC COAST WILL HAVE
MOISTURE FEED OFF THE WATER COMING INTO THE AREA WITH SOME RISE TO
THE EAST WINDS AS THEY APPROACH THE RIDGES TO THE WEST. BY MONDAY
THIS FEATURE IS WEAKENING AND MORE NORTHEAST AWAY FROM THE AREA.
HOWEVER WILL STILL HAVE PLENTY OF MOISTURE ACROSS THE AREA SO WILL
CONTINUE CHANCE TO SLIGHT CHANCE POPS ESPECIALLY ON MONDAY
AFTERNOON WITH THE BEST CHANCES IN THE WEST WHERE THE LOW LEVEL
EAST WINDS WILL BEGIN TO RISE AS THEY APPROACH THE MOUNTAINS TO
THE WEST. WILL GO FAIRLY CLOSE TO MOS GUIDANCE FOR TEMPERATURES
WITH THE WARMEST DAY ON MONDAY AS LESS CLOUD COVER THEN. LOWS AT
NIGHT WILL MAINLY BE IN THE MID TO UPPER 60S.
&&
.LONG TERM /MONDAY NIGHT THROUGH FRIDAY/...
PERIOD BEGINS WITH A BROAD MID/UPPER LEVEL RIDGE CENTERED OVER
MUCH THE SOUTHERN TIER OF THE CONUS...GRADUALLY EVOLVING INTO A
STRONG RIDGE OVER THE SW STATES WITH A FAIRLY DEEP TROUGH CENTERED
JUST NORTH OF THE GREAT LAKES ACRS ONTARIO CANADA. THIS WILL
TRANSLATE INTO A W/NW UPPER FLOW PATTERN INTO THE MID ATLC STATES.
WHILE A SERIES OF WEAK SHORTWAVES BEGIN TO SHUNT THE RIDGE OFF TO
THE S/SW OF THE CWA TUE/WED...TIMING THESE FEATURES IN THE MEDIUM
RANGE IS QUITE DIFFICULT SO WILL GENLY HAVE ONLY A 20% CHANCE FOR
MAINLY DIURNAL/AFTN/EVENING TSTMS TUE/WED. TEMPERATURES WILL WARM
TO A LITTLE ABOVE AVG FOR LATE JUNE...MAINLY IN THE UPPER 80S TO
LOWER 90S FOR HIGHS WITH LOWS IN THE UPPER 60S TO LOWER 70S. BY
THU/FRI...A MORE DEFINED SFC BOUNDARY SETS UP NOT TOO FAR TO THE
NORTH OF THE CWA...AND 500 MB HEIGHTS SLOWLY FALL...SO HAVE POPS
HIGHER THAN CLIMO BOTH DAYS (ESPECIALLY FRI). HIGHS IN THE UPPER
80S TO LOWER 90S AND LOWS MAINLY FROM 70-75.
&&
.AVIATION /11Z SATURDAY THROUGH WEDNESDAY/...
APART FROM LINGERING IFR/LIFR IVOF KSBY, GENERALLY VFR/MVFR AT
AREA TERMINALS THIS MORNING.
STILL EXPECTING SCT SHRAS TO PUSH NW FROM COASTAL CAROLINAS
TOWARDS COASTAL TERMINALS LATER THIS MORNING, AND HV LEANED ON
HRRR IN TAKING THE PARENT LOW AND THE ASSOCIATED PCPN SHIELD N-NW
INTO NE NC. GIVEN UNCERTAINTY WITH TIMING OF SHRAS, HV GONE WITH
VCSH NOW IN THE TAF AT PHF/ECG/ORF. DO EXPECT TO SEE SOME BREAKS
IN STRATUS AT RIC/SBY AFTER 13-15Z, BUT HV GONE WITH VICINITY SHRA
WORDING AT RIC AFTER 16Z. LOW PRESSURE WL SLOWLY WEAKEN TO OUR
SOUTH,W/ CIGS WL GENERALLY TO RANGE FROM MVFR TO VFR THROUGH THE
AFTN.
OUTLOOK: MORE LATE NIGHT STRATUS IS EXPECTED LATE TONIGHT/SUN
MORNING. OTHERWISE, EXPECT PREDOMINATE VFR CONDITIONS ASIDE FROM
SCATTERED MAINLY DIURNALLY DRIVEN SHRAS SUN AND THROUGH MIDWEEK
AS BREEZY S-SW FLOW REDEVELOPS MON-TUE.
&&
.MARINE...
LATEST OBS CONTINUE TO INDICATE ONSHORE (EAST) FLOW ACRS THE ENTIRE
REGION. WINDS ARE GENLY 15 KT OR LESS (LIGHTEST OVER NORTHERN
AREAS). SEAS CONTINUE TO SLOWLY SUBSIDE THIS MORNING, NOW AOB 4FT
ACROSS THE MID-ATLANTIC WATERS.
NO MAJOR CHANGES TO THE GOING FORECAST WITH THIS PACKAGE. MSAS 3-HR
PRESSURE FALLS CONTINUES TO SHOW SLOW WEAKENING/SLACKENING OF THE
PRESSURE GRADIENT BETWEEN THE INVERTED SFC TROUGH/LOW NEAR KILM AT
08Z AND HIGH PRESSURE OFF NORTHERN MID-ATLANTIC COAST. ACCORDINGLY,
CONTINUE TO EXPECT CONDITIONS TO REMAIN SUB-SCA TODAY. STILL RATHER
UNFAVORABLE BOATING CONDITIONS TODAY, WITH PREDOMINATE LLVL FLOW OUT
OF THE E/NE FLOW AGAIN TODAY WITH SEAS 4 FT AND WAVES 2-3 FT AT THE
MOUTH OF THE BAY.
AS COASTAL FRONT PUSHES BACK WEST THIS AFTN/EVENING, EXPECT WINDS TO
GRADUALLY VEER AROUND TO THE ESE, THEN THE SSE BY 06Z/2A SAT
NIGHT/SUN MORNING WITH SPEEDS AOB 10 KT. THEREAFTER, GOOD MODEL
AGREEMENT IN SETTING UP A RATHER STAGNANT, BUT FAIRLY BENIGN PATTERN
FROM LATE SUN THROUGH THE MIDDLE OF NEXT WEEK. SSW WINDS WL AVERAGE
AOB 15KT OUTSIDE OF ANY DEVELOPING AFTN/EVENING CONVECTION. WAVES
1-2 FT ON THE BAY/SND/RVRS...SEAS GENERALLY 2-4 FT (HIGHEST NORTHERN
COASTAL WATERS).
&&
.AKQ WATCHES/WARNINGS/ADVISORIES...
MD...MODERATE RIP CURRENT RISK THROUGH THIS EVENING FOR MDZ025.
NC...MODERATE RIP CURRENT RISK THROUGH THIS EVENING FOR NCZ102.
VA...MODERATE RIP CURRENT RISK THROUGH THIS EVENING FOR VAZ098>100.
MARINE...NONE.
&&
$$
SYNOPSIS...JAB
NEAR TERM...JAB
SHORT TERM...JAB
LONG TERM...LKB
AVIATION...MAM
MARINE...MAM
AREA FORECAST DISCUSSION
NWS DULUTH MN
917 AM CDT SAT JUN 22 2013
.UPDATE...
WE UPDATED GRIDS FOR THE SHORT TERM TO ACCOUNT FOR LATEST RADAR
TRENDS. WE REDUCED POPS OVER THE NEXT COUPLE HOURS...BUT DO EXPECT
INCREASING COVERAGE AS THE DAY PROGRESSES. LATEST SPC OUTLOOK
REDUCED THE NORTHWARD EXTENT OF THE SLIGHT RISK AREA FOR SEVERE
STORMS. GIVEN HOW FAR SOUTH THE WARM FRONT IS ATTM...WE AGREE
WITH THAT MOVE. ALTHOUGH SOME STRONGER STORMS MAY STILL OCCUR OVER
THE CWA THIS AFTERNOON. WE ALSO HAVE CONCERNS THAT SOME STRONGER
STORMS MAY ARRIVE TONIGHT AS THE FRONT TRIES TO MOVE NORTH AGAIN
AND WITH AN INCREASING LLJ. A QUICK LOOK AT THE LATEST NAM REVEALS
INCREASING INSTABILITY AND DEEP LAYER SHEAR OVERNIGHT...SO STRONG
TO POSSIBLY SEVERE STORMS MAY ALSO BE POSSIBLE LATE
TONIGHT...MAINLY OVER THE SOUTHERN HALF OF THE CWA.
THE VISIBILITY HAS RISEN IN SILVER BAY...GRAND MARAIS...ASHLAND
AND IRONWOOD THIS MORNING. IF THESE TRENDS HOLD...WE MAY BE ABLE
TO DROP THE DENSE FOG ADVISORY FOR PORTIONS OF THE NORTH AND SOUTH
SHORES. THE ONSHORE FLOW IS STRONGER IN THE TWIN PORTS AREA...SO
FOG SHOULD REMAIN HERE THE LONGEST.
&&
.PREV DISCUSSION... /ISSUED 701 AM CDT SAT JUN 22 2013/
AVIATION...12Z TAF ISSUANCE...
LOW PRESSURE SYSTEM OVER SWRN MN AND ERN NEB WILL CONTINUE TO
SPREAD SHOWERS AND STORMS THROUGH THE REGION TODAY AND TONIGHT.
THE EXACT TIMING AND PLACEMENT OF PRECIP WILL BE DIFFICULT TO NAIL
DOWN...SO KEPT WITH VCSH LATE MORNING AND AFTERNOON...AND ANOTHER
ROUND OF SHOWERS LATE TONIGHT. HAVE FOG THIS MORNING AT DLH LIFTING
BY 15/17Z...BUT KEEPING LOW CLOUDS IN THROUGH MOST OF THE DAY AND
FOG RETURNING TONIGHT. E/NE WINDS WILL BECOME GUSTY THIS AFTERNOON.
PREV DISCUSSION... /ISSUED 409 AM CDT SAT JUN 22 2013/
SHORT TERM...TODAY THROUGH SUNDAY.
THE FOCUS FOR TODAY THROUGH SUNDAY WILL CONTINUE TO BE PCPN
POTENTIAL...AS WELL AS THE CONTINUED POTENTIAL FOR FOG AND
DRIZZLE. PORTIONS OF THE CWA ARE ALSO IN THE SLIGHT RISK FOR
SEVERE WEATHER TODAY AND TONIGHT.
AT 330 AM...IT WAS ESSENTIALLY DRY ACROSS THE NORTHLAND. THERE
WERE A FEW LIGHT SHOWERS NORTH OF THE IRON RANGE...AND ALSO IN NW
WI. WIDESPREAD SHOWERS AND THUNDERSTORMS CONTINUED FROM EASTERN
SOUTH DAKOTA...THROUGH CENTRAL AND SOUTHERN MN AND SOUTHERN WI
WITH WIDESPREAD MCS ACTIVITY IN THOSE AREAS. DENSE FOG CONTINUED
NEAR LAKE SUPERIOR AND HAVE ISSUED A DENSE FOG ADVISORY FOR LAND
AND WATER AREAS.
THE BIG QUESTION IS THE EVOLUTION OF THE WIDESPREAD SHOWERS AND
THUNDERSTORMS TO THE SOUTH OF THE AREA. AS EXPECTED WITH THIS TYPE
OF PATTERN...THE MODELS REALLY DO NOT HAVE A HANDLE ON THE CURRENT
PRECIPITATION. THERE ARE A FEW EXCEPTIONS...INCLUDING THE 4 KM WRF
AND THE 06Z HRRR RAPID REFRESH. BOTH HAVE A RELATIVELY DECENT
HANDLE ON THE CURRENT PRECIPITATION TRENDS...AND BOTH BRING THE
PRECIPITATION NORTH AND EASTWARD INTO OUR CWA. HAVE DONE SOME
DRAMATIC MODIFICATIONS TO POPS AND WEATHER FOR TODAY. THE TWO HIGH
RESOLUTION MODELS ACTUALLY LIFT IT INTO THE CWA BUT DECREASE THE
PRECIPITATION GRADUALLY. WILL KEEP THIS TREND GOING. HAVE ALSO
ADDED AREAS OF DRIZZLE AND DENSE FOG NEAR LAKE SUPERIOR...WHICH
WILL LIKELY CONTINUE THROUGHOUT THE DAY IN SOME FORM.
FOR LATER TODAY AND TONIGHT...MOST OF THE MODEL SOLUTIONS DO BRING
A DRAMATIC INCREASE IN PRECIPITATION...AS A FRONTAL BOUNDARY
STRETCHES FROM SW TO NE ACROSS THE AREA. WILL INCREASE POPS LATER
TODAY AND TONIGHT. COULD STILL SEE SOME STRONG TO SEVERE STORMS IF
WE ARE ABLE TO SEE ENOUGH DAYTIME HEATING FOR SURFACE BASED
CONVECTION. THE FAIRLY HIGH CHANCE OF SHOWERS AND THUNDERSTORMS
WILL ALSO CONTINUE ON SUNDAY...AS THE FRONT REMAINS IN THE AREA.
WILL DEFINITELY NEED TO CONTINUE TO MONITOR THE THREAT OF FLOODING
ACROSS THE AREA. PRECIPITABLE WATER VALUES ARE ON THE ORDER OF 1.8
INCHES TODAY INTO SUNDAY...SO THERE IS ABUNDANT AVAILABLE MOISTURE.
TEMPS WILL BE TROUBLESOME TODAY BASED ON CLOUDS AND PCPN TRENDS.
OVERALL WE SHOULD SEE 70S FOR MOST AREAS TODAY AND SOME 80S
SUNDAY. IT WILL BE DRAMATICALLY COOLER NEAR LAKE SUPERIOR WITH
SOME FAIRLY STRONG NORTHEAST WINDS.
LONG TERM...SUNDAY NIGHT THROUGH FRIDAY NIGHT...
UPPER LOW AND CO-LOCATED SFC LOW WILL MOVE FROM SRN MANITOBA AND WRN
ONTARIO TO THE E/NE ACROSS NRN/CENTRAL ONTARIO SUNDAY NIGHT AND
MONDAY MORNING. A TRAILING COLD FRONT WILL SWEEP ACROSS THE UPPER
MIDWEST AND BRING RAIN SHOWERS AND THUNDERSTORMS TO MUCH OF THE
NORTHLAND THROUGH MON MORNING. HIGH PRESSURE IS EXPECTED TO BUILD IN
ACROSS NRN MN LATE MON AFTERNOON AND INTO MONDAY NIGHT. THIS WILL
ALLOW CONDITIONS TO REMAIN QUIET...AT LEAST UNTIL TUE MORNING WHEN
THE NEXT FRONT IS EXPECTED TO LIFT NWD THROUGH THE REGION AND SPREAD
ANOTHER ROUND OF SHOWERS AND STORMS THROUGH WED EVENING. AN AREA OF
LOW PRESSURE WILL DEVELOP OVER S-CENTRAL CANADA...ON THE NWRN FLANK
OF THE SFC TROUGH/WARM FRONT...AND MOVE EWD INTO NRN ONTARIO ON
THURSDAY. THIS LOW PRESSURE WILL DRAW IN SLIGHTLY COOLER AIR FROM
NRN CANADA AND MODIFY LOW LEVEL THERMAL PROFILES ACROSS NRN MN
ENOUGH TO TRIGGER SHOWERS AND STORMS ACROSS THE REGION THROUGH
FRIDAY.
TEMPERATURES MONDAY THROUGH THURSDAY WILL BE WARM WITH HIGHS IN THE
70S AND 80S...AND 60S AROUND THE PERIPHERY OF LAKE SUPERIOR.
OVERNIGHT LOWS WILL BE MILD WITH TEMPS DROPPING INTO THE UPPER 50S
AND 60S.
AVIATION.../06Z TAF ISSUANCE/
NEXT FEW HOURS A CLUSTER OF THUNDERSTORMS MAY AFFECT KHYR WITH IFR
CIGS AND MVFR VSBYS. OTHERWISE...LAKE EFFECTS ARE PRODUCING
STRATUS OVER MOST OF THE REGION WITH MVFR CIGS...WITH LIFR AT KDLH.
STRATUS HAS LOTS OF HOLES STILL AT KBRD AND KHYR...AND KINL HAS
NOT BEEN AFFECTED AT ALL. THIS STRATUS LAYER SHOULD CONTINUE
OVERNIGHT WITH SOME MVFR FOG ALSO EXPECTED. KDLH TO REMAIN LIFR IN
FOG AND STRATUS WITH THE LIGHT EAST WINDS CONTINUING. WINDS TO
TURN MORE SOUTHERLY SATURDAY IN THE 15Z-18Z TIME RANGE AND EXPECT
CIGS TO IMPROVE DURING THE DAY. SHOWERS AND THUNDERSTORMS ARE
EXPECTED DURING THE AFTERNOON FOR AT LEAST A SHORT TIME...BUT
TIMING AND LOCATION STILL UNCERTAIN SO HAVE LEFT AS VCTS FOR NOW.
&&
.POINT TEMPS/POPS...
DLH 62 57 77 60 / 60 70 60 60
INL 75 62 77 58 / 50 50 60 60
BRD 76 67 82 61 / 60 70 50 50
HYR 78 69 86 63 / 60 70 60 60
ASX 73 61 83 61 / 70 70 60 60
&&
.DLH WATCHES/WARNINGS/ADVISORIES...
MN...DENSE FOG ADVISORY UNTIL 4 PM CDT THIS AFTERNOON FOR MNZ020-021-
037.
WI...DENSE FOG ADVISORY UNTIL 4 PM CDT THIS AFTERNOON FOR WIZ001>004.
LS...DENSE FOG ADVISORY UNTIL 4 PM CDT THIS AFTERNOON FOR LSZ121-
140>148.
SMALL CRAFT ADVISORY UNTIL 10 PM CDT THIS EVENING FOR LSZ143>146.
&&
$$
SHORT TERM...MELDE
AREA FORECAST DISCUSSION...UPDATED
NWS DULUTH MN
701 AM CDT SAT JUN 22 2013
.AVIATION...12Z TAF ISSUANCE...
LOW PRESSURE SYSTEM OVER SWRN MN AND ERN NEB WILL CONTINUE TO
SPREAD SHOWERS AND STORMS THROUGH THE REGION TODAY AND TONIGHT.
THE EXACT TIMING AND PLACEMENT OF PRECIP WILL BE DIFFICULT TO NAIL
DOWN...SO KEPT WITH VCSH LATE MORNING AND AFTERNOON...AND ANOTHER
ROUND OF SHOWERS LATE TONIGHT. HAVE FOG THIS MORNING AT DLH LIFTING
BY 15/17Z...BUT KEEPING LOW CLOUDS IN THROUGH MOST OF THE DAY AND
FOG RETURNING TONIGHT. E/NE WINDS WILL BECOME GUSTY THIS AFTERNOON.
&&
.PREV DISCUSSION... /ISSUED 409 AM CDT SAT JUN 22 2013/
SHORT TERM...TODAY THROUGH SUNDAY.
THE FOCUS FOR TODAY THROUGH SUNDAY WILL CONTINUE TO BE PCPN
POTENTIAL...AS WELL AS THE CONTINUED POTENTIAL FOR FOG AND
DRIZZLE. PORTIONS OF THE CWA ARE ALSO IN THE SLIGHT RISK FOR
SEVERE WEATHER TODAY AND TONIGHT.
AT 330 AM...IT WAS ESSENTIALLY DRY ACROSS THE NORTHLAND. THERE
WERE A FEW LIGHT SHOWERS NORTH OF THE IRON RANGE...AND ALSO IN NW
WI. WIDESPREAD SHOWERS AND THUNDERSTORMS CONTINUED FROM EASTERN
SOUTH DAKOTA...THROUGH CENTRAL AND SOUTHERN MN AND SOUTHERN WI
WITH WIDESPREAD MCS ACTIVITY IN THOSE AREAS. DENSE FOG CONTINUED
NEAR LAKE SUPERIOR AND HAVE ISSUED A DENSE FOG ADVISORY FOR LAND
AND WATER AREAS.
THE BIG QUESTION IS THE EVOLUTION OF THE WIDESPREAD SHOWERS AND
THUNDERSTORMS TO THE SOUTH OF THE AREA. AS EXPECTED WITH THIS TYPE
OF PATTERN...THE MODELS REALLY DO NOT HAVE A HANDLE ON THE CURRENT
PRECIPITATION. THERE ARE A FEW EXCEPTIONS...INCLUDING THE 4 KM WRF
AND THE 06Z HRRR RAPID REFRESH. BOTH HAVE A RELATIVELY DECENT
HANDLE ON THE CURRENT PRECIPITATION TRENDS...AND BOTH BRING THE
PRECIPITATION NORTH AND EASTWARD INTO OUR CWA. HAVE DONE SOME
DRAMATIC MODIFICATIONS TO POPS AND WEATHER FOR TODAY. THE TWO HIGH
RESOLUTION MODELS ACTUALLY LIFT IT INTO THE CWA BUT DECREASE THE
PRECIPITATION GRADUALLY. WILL KEEP THIS TREND GOING. HAVE ALSO
ADDED AREAS OF DRIZZLE AND DENSE FOG NEAR LAKE SUPERIOR...WHICH
WILL LIKELY CONTINUE THROUGHOUT THE DAY IN SOME FORM.
FOR LATER TODAY AND TONIGHT...MOST OF THE MODEL SOLUTIONS DO BRING
A DRAMATIC INCREASE IN PRECIPITATION...AS A FRONTAL BOUNDARY
STRETCHES FROM SW TO NE ACROSS THE AREA. WILL INCREASE POPS LATER
TODAY AND TONIGHT. COULD STILL SEE SOME STRONG TO SEVERE STORMS IF
WE ARE ABLE TO SEE ENOUGH DAYTIME HEATING FOR SURFACE BASED
CONVECTION. THE FAIRLY HIGH CHANCE OF SHOWERS AND THUNDERSTORMS
WILL ALSO CONTINUE ON SUNDAY...AS THE FRONT REMAINS IN THE AREA.
WILL DEFINITELY NEED TO CONTINUE TO MONITOR THE THREAT OF FLOODING
ACROSS THE AREA. PRECIPITABLE WATER VALUES ARE ON THE ORDER OF 1.8
INCHES TODAY INTO SUNDAY...SO THERE IS ABUNDANT AVAILABLE MOISTURE.
TEMPS WILL BE TROUBLESOME TODAY BASED ON CLOUDS AND PCPN TRENDS.
OVERALL WE SHOULD SEE 70S FOR MOST AREAS TODAY AND SOME 80S
SUNDAY. IT WILL BE DRAMATICALLY COOLER NEAR LAKE SUPERIOR WITH
SOME FAIRLY STRONG NORTHEAST WINDS.
LONG TERM...SUNDAY NIGHT THROUGH FRIDAY NIGHT...
UPPER LOW AND CO-LOCATED SFC LOW WILL MOVE FROM SRN MANITOBA AND WRN
ONTARIO TO THE E/NE ACROSS NRN/CENTRAL ONTARIO SUNDAY NIGHT AND
MONDAY MORNING. A TRAILING COLD FRONT WILL SWEEP ACROSS THE UPPER
MIDWEST AND BRING RAIN SHOWERS AND THUNDERSTORMS TO MUCH OF THE
NORTHLAND THROUGH MON MORNING. HIGH PRESSURE IS EXPECTED TO BUILD IN
ACROSS NRN MN LATE MON AFTERNOON AND INTO MONDAY NIGHT. THIS WILL
ALLOW CONDITIONS TO REMAIN QUIET...AT LEAST UNTIL TUE MORNING WHEN
THE NEXT FRONT IS EXPECTED TO LIFT NWD THROUGH THE REGION AND SPREAD
ANOTHER ROUND OF SHOWERS AND STORMS THROUGH WED EVENING. AN AREA OF
LOW PRESSURE WILL DEVELOP OVER S-CENTRAL CANADA...ON THE NWRN FLANK
OF THE SFC TROUGH/WARM FRONT...AND MOVE EWD INTO NRN ONTARIO ON
THURSDAY. THIS LOW PRESSURE WILL DRAW IN SLIGHTLY COOLER AIR FROM
NRN CANADA AND MODIFY LOW LEVEL THERMAL PROFILES ACROSS NRN MN
ENOUGH TO TRIGGER SHOWERS AND STORMS ACROSS THE REGION THROUGH
FRIDAY.
TEMPERATURES MONDAY THROUGH THURSDAY WILL BE WARM WITH HIGHS IN THE
70S AND 80S...AND 60S AROUND THE PERIPHERY OF LAKE SUPERIOR.
OVERNIGHT LOWS WILL BE MILD WITH TEMPS DROPPING INTO THE UPPER 50S
AND 60S.
AVIATION.../06Z TAF ISSUANCE/
NEXT FEW HOURS A CLUSTER OF THUNDERSTORMS MAY AFFECT KHYR WITH IFR
CIGS AND MVFR VSBYS. OTHERWISE...LAKE EFFECTS ARE PRODUCING
STRATUS OVER MOST OF THE REGION WITH MVFR CIGS...WITH LIFR AT KDLH.
STRATUS HAS LOTS OF HOLES STILL AT KBRD AND KHYR...AND KINL HAS
NOT BEEN AFFECTED AT ALL. THIS STRATUS LAYER SHOULD CONTINUE
OVERNIGHT WITH SOME MVFR FOG ALSO EXPECTED. KDLH TO REMAIN LIFR IN
FOG AND STRATUS WITH THE LIGHT EAST WINDS CONTINUING. WINDS TO
TURN MORE SOUTHERLY SATURDAY IN THE 15Z-18Z TIME RANGE AND EXPECT
CIGS TO IMPROVE DURING THE DAY. SHOWERS AND THUNDERSTORMS ARE
EXPECTED DURING THE AFTERNOON FOR AT LEAST A SHORT TIME...BUT
TIMING AND LOCATION STILL UNCERTAIN SO HAVE LEFT AS VCTS FOR NOW.
&&
.POINT TEMPS/POPS...
DLH 66 57 77 60 / 60 70 60 60
INL 75 62 77 58 / 50 50 60 60
BRD 76 67 82 61 / 70 70 50 50
HYR 78 69 86 63 / 60 70 60 60
ASX 73 61 83 61 / 60 70 60 60
&&
.DLH WATCHES/WARNINGS/ADVISORIES...
MN...DENSE FOG ADVISORY UNTIL 4 PM CDT THIS AFTERNOON FOR MNZ020-021-
037.
WI...DENSE FOG ADVISORY UNTIL 4 PM CDT THIS AFTERNOON FOR WIZ001>004.
LS...DENSE FOG ADVISORY UNTIL 4 PM CDT THIS AFTERNOON FOR LSZ121-
140>148.
SMALL CRAFT ADVISORY UNTIL 10 PM CDT THIS EVENING FOR LSZ143>146.
&&
$$
SHORT TERM...DAP
LONG TERM....TENTINGER
AVIATION...TENTINGER
AREA FORECAST DISCUSSION
NWS BILLINGS MT
947 AM MDT SAT JUN 22 2013
.UPDATE...
SCATTERED TO ISOLATED SHOWERS AND THUNDERSTORMS ARE CONTINUING
FROM BILLINGS EASTWARD THIS MORNING AS A JET MAX IS DRIVING THIS
PRECIPITATION. UPPER TROUGH OVER WESTERN MONTANA THIS MORNING IS
PUSHING SLOWLY EASTWARD AND WILL MOVE ACROSS SC/SE MT THIS
AFTERNOON. ONLY MAJOR ADJUSTMENT TO THE CURRENT FORECAST WAS TO
ADD A CHANCE OF SEVERE THUNDERSTORMS FROM SHERIDAN EAST THROUGH
BROADUS TO EKALAKA FROM 21Z AFTERNOON THROUGH 03Z THIS EVENING.
CONVECTIVE PARAMETERS ARE HIGHLIGHTING THIS AREA FOR THE POTENTIAL
OF LARGE HAIL AND STRONG WINDS. THE UPPER TROUGH WILL BRING IN
STRONG Q VECTOR FORCING ALONG WITH JET DYNAMICS. THE ONLY DRAW
BACK ON THE SEVERE POTENTIAL THIS AFTERNOON/EVENING WILL BE THE
AMOUNT OF SURFACE HEATING THAT WILL TAKE PLACE TODAY. CURRENTLY
LOW LEVEL STRATUS HAS BEEN OVER THIS AREA BUT DUE EXPECT SOME
BREAKS IN CLOUD COVERE THIS AFTERNOON FOR THE BOUNDARY LAYER TO
DESTABILIZE AND STORMS TAPING INTO LOW LEVEL DEW POINTS IN THE
LOW TO MID 50S. NO CHANGES MADE TO HIGH TEMPERATURES FOR TODAY.
RICHMOND
&&
.SHORT TERM...VALID FOR TDY AND SUN...
WIDESPREAD SHOWERS AND STORMS ARE STILL EXPECTED ACROSS THE REGION
THIS AFTERNOON AND EVENING AS THE 500-HPA LOW NEAR BOISE AT 09 UTC
OPENS UP AND SWINGS ACROSS MT. LOCALLY HEAVY RAINFALL IS LIKELY.
FIRST OF ALL...WE WILL INCLUDE SOME PATCHY FOG IN THE FORECAST FOR
PLACES LIKE BAKER AND MILES CITY UNTIL 15 UTC. LOW TEMPERATURE-DEW
POINT SPREADS AS OF 09 UTC AND HRRR FORECASTS BOTH SUPPORT THAT.
TODAY...THE SCATTERED STORMS WHICH HAVE BEEN DEVELOPING OVER SOUTH
CENTRAL MT OVERNIGHT SHOULD LARGELY EXIT THE AREA BY 12 UTC AS THE
RIGHT ENTRANCE REGION OF THE 75+ KT 300-HPA JET STREAK WHICH SEEMS
RESPONSIBLE FOR THIS ACTIVITY HEADS NORTHEAST. MEANWHILE...FORCING
TIED TO THE 500-HPA TROUGH MAY BE A BIT DELAYED WHEN COMPARED WITH
EARLIER EXPECTATIONS. MOST 00 UTC GUIDANCE PICKED UP ON A BIT OF A
SLOW-DOWN WITH THIS SYSTEM...AND THAT LOOKS LIKE A GOOD SIMULATION
SINCE WE STILL HAVE A CLOSED LOW INSTEAD OF AN OPEN WAVE ACROSS ID
EARLY THIS MORNING. BASED ON THIS...WE DECIDED TO ADVERTISE MAINLY
CHANCE POPS ACROSS MUCH OF THE AREA FROM 12 TO 18 UTC...EXCEPT OUT
AROUND LIVINGSTON WHERE FORCING MAY ARRIVE BY LATE MORNING. THE 00
UTC MULTI-MODEL CONSENSUS STILL SUPPORTS CATEGORICAL POPS FOR MOST
OF THE AREA THIS AFTERNOON WHEN STRONGER VERTICAL MOTION SHOWS UP.
PRECIPITABLE WATER VALUES OF 0.75 INCHES OR MORE CERTAINLY SUGGEST
LOCALLY HEAVY RAINFALL IS LIKELY. WHILE MID-LEVEL LAPSE RATES WILL
BE STEEP ENOUGH TO SUPPORT SOME THUNDER...SEVERE RISK WILL BE KEPT
IN CHECK BY A RELATIVELY COOL BOUNDARY LAYER AND RESULTANT LACK OF
CAPE. WE WILL BE WATCHING BURN SCAR AREAS CLOSELY...BUT THE THREAT
OF FLASH FLOODING WAS NOT SIGNIFICANT ENOUGH FOR A WATCH HEADLINE.
FINALLY...NOTE THAT SOME HIGH-ELEVATION SNOW IS LIKELY TODAY BASED
ON WET-BULB ZERO HEIGHTS WHICH SUGGEST A SNOW LEVEL PERHAPS AS LOW
AS 8700 FT MSL. THE BEARTOOTH HIGHWAY IS A GOOD CANDIDATE FOR SOME
SNOW.
TONIGHT...BASED ON THE MULTI-MODEL CONSENSUS...WE KEPT CATEGORICAL
POPS IN THE FORECAST UNTIL 06 UTC FROM HYSHAM AND SHERIDAN EAST TO
BAKER AND EKALAKA. LIKELY POPS ARE EVEN IN PLAY AT BILLINGS DURING
THE EVENING. BY THIS POINT IN TIME...DEEP MOIST CONVECTION WILL BE
ESTABLISHED OVER PARTS OF THE DAKOTAS AND NEBRASKA...AND THAT DOES
POSE THE RISK OF DISRUPTING MOISTURE ADVECTION INTO OUR AREA. EVEN
SO...THE EXPECTED QG-FORCING SHOULD STILL YIELD PRECIPITATION EAST
OF THE 500-HPA TROUGH AXIS. A DRYING TREND WILL BEGIN ACROSS SOUTH
CENTRAL MT OVERNIGHT AS THAT AXIS HEADS EASTWARD.
SUN...WE LINGERED SOME CHANCE POPS FROM MILES CITY TO BAKER DURING
THE MORNING IN RESPECT TO THE BIT SLOWER DEPARTURE OF THE MID- AND
UPPER-LEVEL TROUGH ADVERTISED BY MOST 00 UTC GUIDANCE. WE ACTUALLY
EVEN LEFT LOW POPS IN BAKER AFTER 18 UTC. HOWEVER...IN GENERAL THE
WHOLE AREA WILL HAVE A DRYING AND WARMING TREND AS FLOW ALOFT WILL
BECOME WESTERLY BY AFTERNOON. MIXING TO 700 HPA OR DEEPER BASED ON
FORECAST SOUNDINGS SUPPORTS HIGHS WELL INTO THE 70S F. SCHULTZ
.LONG TERM...VALID FOR MON...TUE...WED...THU...FRI...
EXTENDED FORECAST STARTS MONDAY AS THE FLOW OPENS UP TO THE
SOUTHWEST AGAIN. WEAK SHORTWAVES GET PULLED ACROSS THE AREA MONDAY
AFTERNOON BUT THE ATMOSPHERE IS PROGGED TO BE FAIRLY DRY SO WILL
KEEP POPS LOW. A STRONG SHORTWAVE IS PROGGED BY THE GFS TO SWING
ACROSS WESTERN ZONES MONDAY EVENING AND THIS SHOULD GENERATE
SCATTERED THUNDERSTORMS AS MOISTURE GETS PULLED IN WITH THIS
SYSTEM.
THE BEST CHANCE OF PRECIPITATION DURING THE EXTENDED PERIOD LOOKS
TO BE ON TUESDAY. HEIGHTS LOWER AS SEVERAL SHORTWAVES DRIFT ACROSS
WITH A STRONG WAVE EARLY IN THE DAY. TIMING OF THIS WAVE MAY BE
PROBLEMATIC AS IT MAY BE TOO EARLY TO TAP INTO THE STRONGEST
INSTABILITY. THAT BEING SAID...PRECIPITABLE WATERS RISE TO OVER
THREE QUARTERS OF AN INCH. LOW LEVEL FLOW DOES TURN WESTERLY AND
THIS MAY DRY OUT THE LOW LEVELS AND LIMIT PRECIP POTENTIAL. THAT
WILL NEED TO BE WATCHED. WILL KEEP SCATTERED POPS IN FOR NOW BUT
MAY NEED TO BE LOWERED IN THE FUTURE.
A STRONG UPPER RIDGE IS FORECAST TO BUILD WEDNESDAY THROUGH NEXT
WEEKEND. SUBTLE DIFFERENCES STARTING TO SHOW UP THOUGH AS THE
MODELS JUST NOW STARTED TO BUILD THE RIDGE A LITTLE FARTHER WEST
AND SET UP WEAK NORTHWEST FLOW OVER THE AREA. HEIGHTS WERE NOT
QUITE AS HIGH AS PREVIOUS RUNS EITHER. THIS WILL BE A TREND TO BE
WATCHED AS THE ECMWF HINTED AT THE SAME THING. DID RAISE FORECAST
HIGHS THROUGH THE END OF THE WEEK AS 700MB TEMPERATURES WERE A
LITTLE TO WARM FOR INHERITED FORECAST HIGHS. TWH
&&
.AVIATION...
SHOWERS AND THUNDERSTORMS WILL IMPACT THE FORECAST AREA TODAY.
THE MOST WIDESPREAD HEAVY RAINFALL WILL BE EAST OF KBIL TO KSHR.
NUMEROUS SHOWERS AND THUNDERSTORMS ARE EXPECTED WEST OF THIS LINE
AS WELL. MVFR FLIGHT CONDITIONS CAN BE EXPECTED WITH THE HEAVY
RAIN. CONDITIONS WILL IMPROVE THIS EVENING IN THE WEST...OVERNIGHT
IN CENTRAL ZONES AND EARLY SUNDAY OUT EAST. CHURCH
&&
.PRELIMINARY POINT TEMP/POPS...
TDY SUN MON TUE WED THU FRI
-------------------------------------------------------
BIL 068 051/078 054/086 062/086 058/085 059/087 058/089
9/T 61/B 11/B 23/T 31/B 10/U 00/U
LVM 065 041/079 046/083 054/081 053/083 052/085 053/085
8/T 51/B 13/T 34/T 31/B 11/U 11/U
HDN 070 049/078 052/087 059/088 057/087 059/088 059/090
9/T 61/B 11/B 22/T 21/B 11/U 10/U
MLS 073 055/079 056/088 062/088 060/087 059/087 060/087
9/T 83/T 11/B 22/T 21/B 10/U 01/U
4BQ 071 049/079 054/087 059/089 058/089 059/089 059/088
9/T 82/T 11/B 22/T 21/B 11/U 11/U
BHK 070 053/075 054/086 059/086 058/086 059/083 058/084
8/T 83/T 13/T 32/T 21/U 11/U 11/U
SHR 069 045/076 049/085 055/086 053/086 054/086 053/087
+/T 81/U 11/B 22/T 21/B 11/U 11/U
&&
.BYZ WATCHES/WARNINGS/ADVISORIES...
MT...NONE.
WY...NONE.
&&
$$
WEATHER.GOV/BILLINGS
AREA FORECAST DISCUSSION
NWS SPOKANE WA
815 AM PDT Sat Jun 22 2013
.SYNOPSIS...
Lingering showers from the recent storm system will taper off
today. Temperatures will warm to near normal on Sunday. More wet
and cool weather will arrive on late Sunday and persist through
mid week followed by another warming, dry period to close out the
work-week. Temperatures by the end of the week could be the
hottest of the year so far.
&&
.DISCUSSION...
Updates to the forecast this morning concern the coverage of
showers and thunderstorms this afternoon. Instability this
afternoon is decent, with some guidance showing up to 500 J/kg
CAPE across the northern/eastern mountains (GFS has much less
instability). In addition, satellite imagery shows minor waves
moving down from central BC which could aid the lift. Low level
moisture is plentiful with dew points around 50, so no problem
there. With all this in mind, I`ve increased our chances of rain
for this afternoon/evening across the northern/eastern mountains.
Trajectory of the showers could bring a few of them across the
Spokane/CdA metro area but I`m not confident of thunder there.
The HRRR and 4km WRF show some organized convection moving down
from BC and clipping the WA/BC border this afternoon, which is
where my highest PoPs are. They both show some decent storms, but
keep them north of the border. So this will need to be monitored.
Right now I`m not expecting any strong thunderstorms. RJ
&&
.AVIATION...
12Z TAFS: A weak weather disturbance moving south out of BC will
continue to generate mid level clouds across much of the western
basin into the northern mountains of eastern WA. Farther east
across extreme eastern WA and into the ID Panhandle, early morning
clearing has allowed fog and low stratus to develop in many of the
valleys. This fog (or low stratus) may affect the KGEG, KSFF,
KCOE, KPUW and KLWS TAF sites. Late June sunshine should mix this
out by around 16Z. Scattered showers and isolated thunderstorms
will develop over the mountains of NE WA and N ID this afternoon
and evening but chances are low that this will affect any TAF sites.
/EK
&&
.PRELIMINARY POINT TEMPS/POPS...
Spokane 70 51 77 55 70 53 / 20 10 0 40 60 70
Coeur d`Alene 69 48 76 55 69 53 / 20 10 10 20 60 70
Pullman 70 47 77 53 69 53 / 10 0 0 40 60 60
Lewiston 78 54 83 57 75 56 / 0 0 0 40 50 60
Colville 75 48 79 56 72 56 / 60 50 10 20 60 70
Sandpoint 69 45 76 54 69 54 / 30 30 10 20 70 80
Kellogg 66 48 74 54 67 53 / 20 20 10 20 70 70
Moses Lake 80 53 82 58 75 55 / 0 0 10 40 50 40
Wenatchee 80 57 80 58 74 54 / 0 0 10 50 60 40
Omak 79 54 80 57 73 56 / 10 10 10 40 60 60
&&
.OTX WATCHES/WARNINGS/ADVISORIES...
ID...None.
WA...None.
&&
$$
AREA FORECAST DISCUSSION
NWS MILWAUKEE/SULLIVAN WI
1020 AM CDT SAT JUN 22 2013
.UPDATE...
N-S CONVECTIVE BAND OVER SOUTHERN WI WILL CONTINUE TO MOVE EAST TO
OVER LAKE MICHIGAN BY EARLY AFTERNOON. HAVE UPDATED THE FORECAST TO
REFLECT THIS AND INCREASED CHANCES OF RAIN TO CATEGORICAL. HAVE
KNOCKED MAX TEMPS DOWN A FEW DEGREES SINCE USUAL DAYTIME HEATING
WILL NOT BE THERE. IN FACT...WE WILL PROBABLY KNOCK THEM BACK IN
MORE SINCE IT`LL BE MOSTLY CLOUDY WITH CONVECTIVE CLOUD CANOPY
OVERHEAD. YESTERDAY WE NEVER RECOVERED PAST 80.
THE AFTERNOON HOURS SHOULD BE QUIET AFTER THE CONVECTIVE BAND
EXITS....LIKE YESTERDAY. FORECAST MODELS..BOTH THE LARGE SCALE AND
MESO TYPES HAVE VARIOUS SOLUTIONS FOR THUNDERSTORM POSSIBILITIES
THIS AFTERNOON AND TONIGHT. GIVEN THAT LOW LEVEL BOUNDARY HAS BEEN
SHOVED BACK SOUTH INTO NORTHERN ILLINOIS MAKES IT DIFFICULT TO GET
REGENERATION OF STORMS OVER SOUTHERN WI UNTIL LATE IN THE
AFTERNOON. HRRR MODELS HINTS AT THIS.
.AVIATION/18Z TAFS/...
JUST PRIOR TO 18Z THERE WERE POCKETS OF IFR CIGS ALONG OR NEAR THE
LAKE MICHIGAN SHORELINE FROM MILWAUKEE TO KENOSHA. EXPECT THESE
CONDITIONS TO BE REINFORCED BY CONVECTIVE RAIN BAND WHICH WILL MOVE
FROM SOUTHCENTRAL INTO SOUTHEAST WISCONSIN AND THEN OVER LAKE
MICHIGAN. OTHERWISE...VFR CONDS WITH MULTIPLE LAYERS OF CLOUDS.
BRIEF MVFR VSBY CONDITIONS WITH THE HEAVIER SHOWERS/RAIN. CIGS AND
VISIBILITIES SHOULD BE UP AND DOWN SATURDAY NIGHT WITH ADDITIONAL
CHANCES OF SHOWERS AND STORMS. HOWEVER...GENERALLY VFR CONDS
EXPECTED.
.PREV DISCUSSION...ISSUED 238 AM CDT SAT JUN 21 2013
.SHORT TERM...TODAY AND TONIGHT...FORECAST CONFIDENCE IS MEDIUM.
THE 250 MB UPPER RIDGE EXTENDS FROM THE SOUTHEAST U.S. INTO THE LAKE
MICHIGAN AREA...WITH A SHORTWAVE OVER THE NORTHERN ROCKIES. AT 500
MB A MODERATE SOUTHWEST FLOW WILL PERSIST ACROSS THE NORTHERN
PLAINS TO NORTHWEST WISCONSIN.
ACTIVE THUNDERSTORM FORECAST FOR THIS PERIOD ACROSS THE AREA. SHORT
TERM MODELS INDICATE THE SURFACE WARM FRONT WILL BE NEAR THE
FORECAST AREA AND TENT TO SHIFT NORTHWARD TONIGHT. 850MB THERMAL
RIDGE WILL REMAIN POINTED INTO THE REGION TODAY AND TONIGHT.
THE NOSE OF THE 850MB LOW LEVEL JET IS ACROSS SOUTHERN WISCONSIN
EARLY THIS MORNING...THEN PUSHES EAST TOWARDS THE EASTERN GREAT
LAKES WHILE THE MAIN JET ACROSS THE CENTRAL PLAINS INTO IOWA TODAY
WITH A 30 KNOT FLOW ACROSS SOUTHERN WISCONSIN AGAIN TONIGHT.
PRECIPITABLE WATER VALUES REMAIN HIGH AROUND 1.5 TO 2 INCHES.
NONE OF THE MESO MODELS ARE DOING A VERY GOOD JOB WITH THE
THUNDERSTORMS. IT APPEARS A WEST TO EAST LINE OF THUNDERSTORMS
EXTENDS FROM THE IOWA MINNESOTA BORDER TO SOUTHERN LAKE MICHIGAN
JUST NORTH OF THE 850 MOISTURE TRANSPORT VECTORS. THE EAST PART OF
THIS LINE WAS SAGGING SOUTH...BUT WEST OF MADISON THERE IS A SLOW
NORTH PUSH.
THIS WOULD SUPPORT A LARGE MCC WHICH SHOULD AFFECT THE FORECAST AREA
THIS MORNING. THEN MORE STORMS COULD FORM THIS AFTERNOON AND
TONIGHT. HEAVY RAINFALL IS EXPECTED AND A FLASH FLOOD WATCH MAY BE
NEEDED. HOWEVER THE CURRENT SHORT TERM MESO MODELS WOULD NOT
INDICATE ENOUGH RAINFALL FOR THIS.
TEMPERATURES ARE GOING TO BE TOUGH AS WELL...DEPENDING ON CONVECTION
TRENDS AND CLOUDS. M ID 80S MOST LIKELY GIVEN THE EXPECTED CLOUD
DEBRIS. HOWEVER WITH THE HIGH DEW POINTS IT WILL BE HUMID.
.SUNDAY THROUGH MONDAY NIGHT...FORECAST CONFIDENCE MEDIUM.
MAIN CONCERNS ARE WX/POPS AND HIGH TEMPERATURES. SUNDAYS WEATHER
ARE TIED TO WHETHER OR NOT A MESOSCALE LIFTING MECHANISM WILL BE
PRESENT AND CAP CAN HOLD. OTHERWISE THE OTHER INGREDIENTS FOR DEEP
MOIST CONVECTION WILL BE PRESENT - A MODERATELY UNSTABLE ENVIRONMENT
WITH AT LEAST 1500-2000 J/KG MEAN LAYER CAPE AND AMPLE LOW-LEVEL
MOISTURE WITH SURFACE DEW POINTS AROUND 70. THOUGH STORM MODE AND
ORGANIZATION WILL BE A LIMITING FACTOR IN ALL OF THIS GIVEN THE LOW
VALUES OF DEEP LAYER 0-6 KM SHEAR. DRY CONDITIONS MAY BE SEEN IF
THE CAP HOLDS AND SUNDAY LACKS A LIFTING MECHANISM. KEPT A SLIGHT
CHANCE/CHANCE GIVEN THE UNCERTAINTY.
THE BETTER CHANCE FOR PRECIP EXISTS SUNDAY NIGHT INTO MONDAY.
WHEREIN...NUMERICAL MODELS ARE IN A GENERAL AGREEMENT OF A SHORT
WAVE TROUGH AND AN ASSOCIATED VORT MAX MOVING THROUGH THE AREA
OVERNIGHT/EARLY MONDAY. PRECIP CHANCES CONTINUE MONDAY AS PRECIP
FROM THE MORNING COULD LINGER AND GIVEN THE SUPPORT OF SYNOPTIC
LIFT...SEEN WITH LOW-LEVEL Q-VECTOR DIVG IN PLACE AND LIGHT LOW-
LEVEL WAA OCCURRING.
THE MODEL CONSENSUS FOR 925 HPA TEMPS SUNDAY ARE AROUND 24-26 C THAT
CORRESPOND TO 87-91 F PROVIDED INSOLATION/MIXING IS SUFFICIENT. ANY
CONVECTIVE DEBRIS THOUGH WOULD IMPACT THIS. RH FIELDS AND WHAT IS
EXPECTED REGARDING WX/POPS GIVE CONFIDENCE TO LEAN TOWARDS THE
HIGHER GUIDANCE WITH HIGHS IN THE UPPER 80S-AROUND 90 FORECAST.
HEAT INDICES ARE EXPECTED TO BE GENERALLY IN THE MID TO UPPER 90S
SUNDAY.
.LONG TERM...TUESDAY THROUGH FRIDAY NIGHT...FORECAST CONFIDENCE
MEDIUM.
SHIFT IN THE PATTERN STILL EXPECTED THIS WEEK WITH A MORE ZONAL 500
HPA PATTERN DEVELOPING MONDAY-TUESDAY ASSOCIATED WITH HT RISES IN
THE NORTHERN ROCKIES AND GREAT PLAINS SUNDAY-EARLY MONDAY. CHANCES
FOR PRECIP WILL CONTINUE INTO THE NEW WORK WEEK AS SHORT WAVES
TROUGHS TRAVERSE THE REGION WITH THE BEST CHANCES TUESDAY
AFTERNOON INTO WEDNESDAY. HIGHS ABOVE NORMAL UNTIL FRIDAY WHEN
PATTERN BREAKS DOWN AS A LONG WAVE TROUGH DEVELOPS OVER THE GREAT
LAKES REGION. NORTHWEST FLOW WILL USHER COOLER AIR FRIDAY AND
SATURDAY WITH HIGHS MOVING TOWARDS BELOW/NEAR NORMAL SEASONAL
VALUES.
&&
.AVIATION/12Z TAFS/...
A BAND OF THUNDERSTORMS WILL EXTEND ACROSS SOUTHERN WISCONSIN
DURING THE EARLY MORNING HOURS. MVFR/IFR IN STORMS...WITH VFR TO
THE NORTH OF THE BAND. SOME MVFR CLOUDS THIS MORNING...THEN MAINLY
VFR. THE CHANCE OF THUNDERSTORMS WILL CONTINUE THIS AFTERNOON AND
TONIGHT WITH A WARM FRONT ACROSS/NEAR SOUTHERN WISCONSIN.
&&
.MARINE...
DEW POINTS RISING THROUGH THE 60S WILL OVERSPREAD THE COOL LAKE
WATERS TODAY AND TONIGHT. SOME FOG FORMATION IS POSSIBLE...AND MAY
LINGER ON AND OFF THROUGH THE WEEKEND.
&&
.MKX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
LM...NONE.
&&
$$
TODAY/TONIGHT AND AVIATION/MARINE...SH
SUNDAY THROUGH FRIDAY...ET
AREA FORECAST DISCUSSION
NWS GREEN BAY WI
653 AM CDT SAT JUN 22 2013
UPDATED AVIATION PORTION FOR 12Z TAF ISSUANCE
.SHORT TERM...TODAY...TONIGHT...AND SUNDAY
ISSUED AT 442 AM CDT SAT JUN 22 2013
CONTINUE WITH ISSUES ON WHERE AND WHEN CONVECTION WILL AFFECT
AREA. WATER VAPOR IMAGERY SHOWING NUMBER OF DISTURBANCES MOVING
THROUGH SOUTHWEST FLOW ALOFT OVER UPPER MIDWEST. CONVECTION
ASSOCIATED WITH THESE DISTURBANCES CURRENTLY EXTENDS OVER SOUTHERN
WI THROUGH MN AND NEBRASKA. MAIN ISSUES TONIGHT WITH THE
CONVECTION...HEAVY RAIN. IR IMAGERY SHOWING WARMING TOPS ATTM WITH
DOWNWARD TREND EXPECTED TO CONTINUE INTO THE MORNING HOURS. OVER
NORTHEAST WI...STABLE AIR FILTERED SOUTH BEHIND BOUNDARY DROPPING
SOUTH OUT OF LAKE SUPERIOR DURING THE EVENING. MODEL OF CHOICE
QUESTIONABLE...WHILE GFS AND TO SOME EXTENT EC APPEARED TO BE
DOING WELL AT 6Z WITH CONVECTIVE TRENDS...THEY QUICKLY LOSE
REALITY AS MOVE INTO THIS MORNING. HAVE TRENDED TOWARDS CURRENT
RADAR TRENDS AND HRRR WHICH BRINGS WAINING CONVECTION NORTH INTO
CENTRAL AND NORTH CENTRAL WI THIS MORNING. THUS WILL GO HIGH
CHANCE OR LIKELY OVER THESE LOCATIONS FOR FIRST PART OF DAY.
REMAINDER OF AREA...LOWER CHANCE POPS THROUGH THE DAY. HRRR
SUGGEST LIMITED PCPN THROUGH AFTERNOON. THIS MAKES SENSE AS BEST
FORCING/ ISENTROPIC LIFT WEST OVER SOUTHERN MN THIS
AFTERNOON...EVENING. MODELS CONTINUE TO TRY AND BRING WARM FRONT
NORTH THROUGH THE AREA TONIGHT. WITH UNCERTAINTY...WILL STICK TO
CHANCE POPS THROUGH SUN. COLD FRONT APPROACHES STATE LATE IN DAY
SUN AS MAIN UPPER WAVE LIFTS NORTHEAST THROUGH HIGH PLAINS.
TRENDED POPS HIGHER WEST GIVEN PROXIMITY OF FRONT.
AGAIN OVERNIGHT STORMS PRODUCED SIG PCPN AS HAVE PLENTY OF
MOISTURE TO WORK WITH WITH PW`S IN 1.5 TO 2.0 INCH RANGE. THIS TO
CONTINUE INTO SUNDAY. PLENTY OF INSTABILITY AROUND THROUGH THE
PERIOD...THOUGH SHEAR IS LIMITED AT LEAST UNTIL SUN...WHEN MODELS
SUGGEST INCREASES TO NR 40 KTS. WILL CONTINUE TO HIGHLIGHT HEAVY
RAIN POTENTIAL AS MAIN ISSUE...WITH STRONG DAMAGING WIND THREAT
POSSIBLE TODAY AND TONIGHT.
GIVEN LOW CLOUDS/CLOUDS EXPECTED FOR FIRST HALF OF DAY AND
EASTERLY COMPONENT OF WIND...HAVE DROPPED HIGHS A GOOD 5 DEGS
TODAY. HAVE NOT MADE ANY SIG CHANGE TO SUN ATTM DUE TO UNCERTAINTY
ON CONVECTION.
.LONG TERM...SUNDAY NIGHT THROUGH FRIDAY
ISSUED AT 442 AM CDT SAT JUN 22 2013
UPPER RIDGE WILL GRADUALLY RETROGRADE WESTWARD INTO THE WESTERN
UNITED STATES. THIS WILL EVENTUALLY CHANGE THE SOUTHWEST FLOW
PATTERN TO A NORTHWEST FLOW PATTERN...BRINGING COOLER TEMPERATURES
AND LOWER HUMIDITY BY THE END OF THE WEEK.
CONSIDERING MODELS ARE HAVING TOUGH TIME OVER THE LAST FEW DAYS
IN THE PLACEMENT OF CONVECTION AND LOCALLY HEAVY RAIN...LOWER
THAN NORMAL CONFIDENCE IN THE DETAILS OF THE FORECAST AS THE MODELS
CONTINUE TO SHOW SEVERAL COMPLEXES MOVING ACROSS THE WESTERN GREAT
LAKES EARLY TO MIDDLE OF NEXT WEEK. THEREFORE...WILL CONTINUE CHANCES
OF SHOWERS AND THUNDERSTORMS EACH DAY THROUGHOUT THE PERIOD. SOME
INDICATIONS BY THE MODELS THAT MONDAY COULD END UP BEING DRIER THAN
ADVERTISED...BUT WILL BELIEVE IT WHEN I SEE IT.
STILL THE POTENTIAL FOR SEVERE WEATHER AND LOCALLY HEAVY EARLY TO
MIDDLE PORTIONS OF NEXT WEEK. HAZARDOUS WEATHER OUTLOOK HAS THIS
MENTIONED ALONG WITH THE UNCERTAINTY IN TIMING. ONLY MINOR CHANGES
MADE TO THE EXTENDED FORECAST ON A FEW DAYS...MORE COORDINATION
PURPOSES.
&&
.AVIATION...FOR 12Z TAF ISSUANCE
ISSUED AT 638 AM CDT SAT JUN 22 2013
LOW CIGS OVER FAR NORTH ASSOCIATED WITH STABLE NORTHEAST FLOW OFF
LAKE SUPERIOR AND ABUNDANT LOW LEVEL MOISTURE WILL LIFT THIS
MORNING AS DECAYING AREA OF CONVECTION MOVES INTO THE REGION.
MORNING SHOWERS AND THUNDERSTORMS EXPECTED TO CONTINUE TO WANE WITH
QUIET MID DAY PERIOD EXPECTED. SHOWER AND TSTM REDEVELOPMENT
POSSIBLE LATER THIS AFTERNOON ESPECIALLY NORTHWEST PORTION OF WI
AS NEXT UPPER DISTURBANCE MOVES THROUGH. STRONG INSTABILITY IS
EXPECTED...SO STRONG/SEVERE TSTMS WITH TORRENTIAL RAINFALL ARE
POSSIBLE.
&&
.GRB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM.....TE
LONG TERM......ECKBERG
AVIATION.......TE
AREA FORECAST DISCUSSION
NWS DENVER/BOULDER CO
323 PM MDT SAT JUN 22 2013
.SHORT TERM...UPPER LEVEL SHORTWAVE TROUGH NOW PASSING OVER THE
NORTHERN ROCKIES WITH SOUTHWEST FLOW ALOFT OVER COLORADO.
FURTHERMORE A SURFACE TROUGH EXTENDS NORTHWARD ALONG THE FRONT
RANGE FROM A SURFACE LOW IN SOUTHEAST COLORADO. EAST OF THE TROUGH
SFC DEWPOINTS IN THE MID TO UPPER 50S. WESTERN PORTIONS OF THE
DENVER METRO AREA AND FOOTHILLS WEST OF THIS SFC TROUGH DEWPOINTS
IN THE UPPER 30S AND 40S. ON THE PLAINS EVEN WITH THE HIGHER
DEWPOINTS...BOUNDARY LAYER GENERALLY REMAINS CAPPED WITH LOW CIN
VALUES BASED ON LAPS AND RAP MODEL...PARTICULARLY IN THE FAR
NORTHEAST CORNER WHERE LOW CLOUDS FROM EARLIER TODAY HAVE BEEN
RELUCTANT TO BURN AWAY. ISOLATED CONVECTION DEVELOPING OVER
NORTHERN AND CENTRAL PORTIONS OF THE FRONT RANGE NOT PRODUCING
MUCH PRECIP YET AS PER RADAR...BUT WITH THE DRY SUB-CLOUD
ENVIRONMENT...POTENTIAL FOR STRONG/GUSTY MICROBURST WINDS PRETTY
HIGH. IT NOW APPEARS THAT STORM DEVELOPMENT ON THE PLAINS WILL
BEGIN ALONG THE PALMER DIVIDE AND ALONG A CONVERGENCE BOUNDARY
STRADDLING THE DENVER METRO AREA WHERE THE CAP AND BROKEN. THESE
STORMS SHOULD THEN TRACK NORTHEAST INTO DEEPER MOISTURE/GREATER
CAPES WHERE A FEW MAY BECOME SEVERE. AT THIS TIME SHEAR PROFILE
LOOKS MARGINAL FOR TORNADOES. BIGGEST THREAT FROM ISOLATED/WIDELY
SCATTERED MESOS WILL BE LARGE HAIL AND DAMAGING OUTFLOW WINDS...
AND PROBABLY NOT UNTIL AFTER 23Z THIS AFTERNOON. BELIEVE THE
CHANCE FOR SEVERE WEATHER WILL INCREASE OVER THE FAR NORTHEAST
CORNER OF THE STATE EARLY THIS EVENING WITH THE PASSAGE OF A WEAK
UPPER AIR DISTURBANCE VISIBLE ON WATER VAPOR IMAGERY NOW OVER WRN
WY/EXTREME NWRN CO. HAIL AT LEAST UP TO 2 INCHES AND WIND GUSTS TO
AT LEAST 60 MPH A POSSIBILITY.
OVERNIGHT...STORMS IN THE NORTHEAST SHOULD EITHER DISSIPATE OR
MOVE EAST OF THE STATE...LEAVING BEHIND AMPLE LOW LEVEL MOISTURE
IN THE FORM OF A THICK BLANKET OF STRATUS/STRATO-CUMULUS SIMILAR
TO WHAT WE SAW THIS MORNING. DURING THE DAY TOMORROW SOUTHWEST
FLOW ALOFT RESUMES BUT WITH A PRETTY VIGOROUS PERTABATION EMBEDDED
IN THIS FLOW. MODELS SHOW THIS FEATURE LIFTING NORTHEAST ACROSS
THE FORECAST AREA DURING THE AFTERNOON. MEANWHILE COUPLED
CIRCULATION AROUND A SFC LOW IN SE COLORADO AND A STRONG SFC HIGH
IN THE BLACK HILLS AREA WILL HELP TO FUNNEL LOW LEVEL MOISTURE
INTO NORTHEAST COLORADO ON EAST-SOUTHEASTERLY WINDS. SUCH A BNDRY
LAYER FLOW OFTEN GENERATES A DENVER CYCLE AS THE NAM INDICATES.
THIS WOULD POTENTIALLY INCREASE THE RISK OF T-STORMS ALONG AND
EAST OF THE FRONT RANGE AND PERHAPS A THREAT OF HAIL. WITH PW AND
THETA-E VALUES ON THE RISE TOMORROW...LOCALLY HEAVY RAINFALL ALSO
POSSIBLE SOMEWHERE ON THE PLAINS. COOLING ALOFT COUPLED WITH
INCREASED MOISTURE/IE...CLOUD COVER/MEANS LOWER TEMPERATURES. MAX
TEMPERATURES TOMORROW NEAR AVERAGE FOR THE DATE. FOR ALL OF THE
SAME REASONS...RED FLAG WATCH/WARNING NOT NECESSARY.
.LONG TERM...SOUTHWESTERLY FLOW ALOFT IS PROGGED FOR SUNDAY
NIGHT...THEN ZONAL FLOW MOVES IN AND CONTINUES THROUGH TUESDAY
NIGHT. SPEEDS ARE IN THE 30 TO 45 KNOT RANGE AT JET LEVEL ALL
FIVE PERIODS. BENIGN SYNOPTIC SCALE ENERGY IS PROGGED THROUGH THE
PERIODS. THE BOUNDARY LAYER FLOW IS PROGGED TO BE EASTERLY UP INTO
THE FOOTHILLS SUNDAY EVENING. BY MONDAY AFTERNOON...SOUTHWESTERLY
LOW LEVEL WINDS RETURN WITH PROGGED SPEEDS OVER THE SOUTH-CENTRAL
AND EASTERN CWA GETTING AROUND 20 KNOTS. FOR MOISTURE...THERE IS
SOME OVER THE EASTERN THREE-QUARTERS OF THE CWA SUNDAY EVENING.
MODELS ALSO SHOW A STRATUS DECK OVER MUCH OF THE PLAINS LATER
SUNDAY NIGHT INTO MONDAY MORNING. THERE IS LESS MOISTURE AROUND
LATE DAY MONDAY...THEN EVEN LESS LATE DAY TUESDAY. SUNDAY NIGHT`S
DEW POINT READINGS ARE PROGGED IN THE MID 40S TO UPPER 50S F FOR
MOST OF THE PLAINS. BY MONDAY LATE DAY...ONLY THE FAR NORTHEASTERN
BORDER HANGS ON TO 40S TO LOWER 50S F...THE REST OF THE PLAINS ARE
IN THE DRY TEENS TO LOWER 30S F. ALL OF THE CWA IS PROGGED TO HAVE
20S TO MID 30S F ON TUESDAY. THERE IS CAPE OVER THE PLAINS AND
MOST OF THE FOOTHILLS SUNDAY EVENING...WITH VALUES IN THE
1000-2000 J/KG RANGE OVER THE EASTERN HALF OF THE PLAINS. THE CAPE
IS PUSHED TO THE FAR NORTHEAST CORNER FOR LATE DAY MONDAY...THEN
NOTHING FOR LATE DAY TUESDAY. THE QPF FIELDS HAVE QUITE A BIT OF
MEASURABLE RAINFALL OVER THE EASTERN HALF OF THE PLAINS SUNDAY
EVENING. THEN THERE IS A TAD PROGGED OVER THE EASTERN BORDER LATE
MONDAY ON THE GFS...THEN NOTHING ANY WHERE ON TUESDAY. FOR
POPS...WILL GO WITH 10-30%S SUNDAY EVENING FROM THE DIVIDE THROUGH
THE EASTERN BORDER. HIGHEST OVER THE EAST. FOR LATE DAY MONDAY
...JUST MINIMAL POPS OVER THE NORTHEAST CORNER. CONCERNING FIRE
DANGER...THE WINDS GET MARGINALLY STRONG ENOUGH FOR RED FLAG
CRITERIA FOR SOME OF THE CWA LATE DAY MONDAY. THE RELATIVE
HUMIDITIES ARE MARGINAL AS WELL. NO HIGHLIGHTS JUST YET. FOR
TEMPERATURES...MONDAY`S HIGHS CLIMB BACK UP 2-3.5 C ABOVE
SUNDAY`S. TUESDAY`S ARE QUITE SIMILAR TO MONDAY`S. FOR THE LATER
DAYS...WEDNESDAY THROUGH SATURDAY...MODELS SHOW AN UPPER RIDGE TO
THE IMMEDIATE SOUTH OF COLORADO TO BUILD NORTHWARD UP INTO THE
STATE WEDNESDAY AND THURSDAY. BY FRIDAY...THE CENTER IS OVER THE
FOUR CORNERS AND IT`S AXIS IS NORTHWARD ACROSS EASTERN UTAH. BY
SATURDAY...THE CENTER MIGRATES A BIT FURTHER WEST INTO THE EASTERN
GREAT BASIN. THE CWA IS MOSTLY IN WEAK NORTHWESTERLY FLOW ALOFT
ALL FOUR DAYS. THIS ALLOWS FOR A COOLER AIRMASS TO GET INTO THE
CWA FRIDAY AND SATURDAY...WE`LL SEE. THERE IS ALSO A LITTLE BIT OF
MOISTURE HERE AND THERE...BUT NOTHING SIGNIFICANT. TEMPERATURES
ARE PRETTY HOT WEDNESDAY AND THURSDAY...THEN COOL OFF FRIDAY AND
SATURDAY.
&&
.AVIATION...ISOLATED STORMS MOVING OFF THE FOOTHILLS AND PALMER
DIVIDE WILL MOST LIKELY BE HIGH BASED. THAT SAID...THESE CELL WILL
HAVE THE POTENTIAL TO PRODUCE A LIGHT RAIN SHOWER...WIND GUSTS TO
AT LEAST 40 MPH AND DANGEROUS CLOUD-TO-GROUND LIGHTNING. THIS
STORM ACTIVITY IS LIKELY TO MOVE EAST OF THE DENVER METRO BY MID-
EVENING. OVERNIGHT SKIES CLEAR...BUT COULD SEE LOW CLOUDS MOVING
CLOSE TO DIA AROUND MORNING LIGHT. TOMORROW THERE IS A BETTER
CHANCE FOR THUNDERSTORMS CERTAINLY BY AFTERNOON WITH PASSAGE OF AN
UPPER LEVEL WEATHER DISTURBANCE. HAIL...STRONG GUSTY WINDS AND
BRIEF HEAVY RAIN WILL BE POSSIBLE. COULD BRIEFLY SEE MVFR
CONDITIONS WITH THIS AFTERNOON CONVECTION.
&&
.FIRE WEATHER...RED FLAG WARNING WILL REMAIN IN EFFECT UNTIL 8 PM
MDT THIS EVENING FOR COLORADO FIREWEATHER ZONES 211-213-214-216
AND 241. GUSTY WINDS...LOW RELATIVE HUMIDITIES AND DRY FUELS MAIN
REASONS FOR THE WARNING.
&&
.HYDROLOGY...STRONG SLOW MOVING T-STORMS OVER THE FAR NORTHEAST
PLAINS THIS EVENING COULD DEPOSIT 1 TO 2 INCHES OF RAIN IN A
SHORT PERIOD OF TIME. STORMS ELSEWHERE THIS AFTERNOON AND EVENING
ARE NOT EXPECTED TO PRODUCE MUCH MORE THAN A QUARTER OF RAIN.
&&
.BOU WATCHES/WARNINGS/ADVISORIES...
RED FLAG WARNING UNTIL 8 PM MDT THIS EVENING FOR COZ211-213-214-
216-241.
&&
$$
SHORT TERM...BAKER
LONG TERM....RJK
AVIATION...BAKER
AREA FORECAST DISCUSSION
NWS GRAND JUNCTION CO
1135 AM MDT SAT JUN 22 2013
.SHORT TERM...(TODAY THROUGH SUNDAY)
ISSUED AT 415 AM MDT SAT JUN 22 2013
WEAK OR SHALLOW FRONT IS LOCATED ACROSS MOFFAT/RIO BLANCO COUNTIES
OF NW COLORADO AND NE UTAH. THERE IS SOME (NOT PLENTIFUL) MID
LEVEL MOISTURE STREAMING ACROSS THIS BOUNDARY AS THE RADAR PICKS
UP LOW DBZ RETURNS. VERNAL ASOS HAS STAYED CLR ALL NIGHT...INDICATING
THAT CLOUD BASES ARE ABOVE 12K FEET. TROUGH AXIS OVER THE NRN
INTERMOUNTAIN REGION LIFTS NORTHEAST TOWARD ERN MONTANA/NERN
WYOMING THIS AFTERNOON. SHORT TERM RAP MODEL SHOWS DRIER AIR
SPREADING INTO NE UTAH/NW COLORADO THIS AFTERNOON BEHIND THE
TROUGH AXIS. WHILE THIS IS A REASONABLE SOLUTION...NOT UNUSUAL FOR
AN ISOLATED THUNDERSTORM TO POP OVER THE ERN UINTAS ALONG THE
TRAILING COLD FRONT. GFS40/NAM12 SHOW LOW END CONVECTIVE POTENTIAL
ACROSS THE NRN MOUNTAINS. WILL MAKE A MINOR ADDITION TO THE
FORECAST AND ADD ISOLATED THUNDERSTORMS OVER THE ERN UINTA
MOUNTAINS. OTHERWISE NO CHANGES WITH SOUTHWEST FLOW AND DEEP MIXED
LAYER WILL GENERATE AFTERNOON BREEZES IN THE 20-30 KT
RANGE...ESPECIALLY PARTS OF NW COLORADO.
TONIGHT AND SUNDAY...
THE PERSISTENT SOUTHWEST FLOW THAT HAS BEEN IN PLACE WILL BE
TEMPORARILY DISRUPTED TONIGHT AS A STRONGER PIECE OF ENERGY LIFTS
ACROSS THE NORTHERN ROCKIES INTO THE NORTHERN PLAINS. THIS WILL TURN
THE UPPER FLOW MORE WESTERLY AND HELP PUSH A FRONT INTO THE WESTERN
AND NORTHERN 1/3 OF THE CWA BY MIDNIGHT. WE WILL BE IN THE
SUBSIDENCE PORTION OF THE WAVE OVERNIGHT WHICH SHOULD HELP CLEAR
THINGS OUT AND BRING SLIGHTLY STRONGER INVERSIONS AND COOLER
TEMPERATURES TO MANY PLACES. THE FRONT WILL BE STALLING AND BECOMING
ILL DEFINE BY SUNRISE ON SUNDAY. ALOFT THE SOUTHWESTERLY FLOW WILL
BEGIN TO RE-ESTABLISH ITSELF AS UPSTREAM TROUGHING ONCE AGAIN MOVES
ALONG THE WEST COAST. THERE WILL BE SOME MOISTURE TRAPPED IN THIS
SOUTHWEST FLOW WITH AN ORIGIN ASSOCIATED WITH THE DEEP STREAM OF
HIGH PWATS IN THE NORTHEAST PACIFIC. PWAT PLOTS OVER GJT SHOW THE
NAM MUCH MORE GENEROUS NEAR A HALF OF AN INCH BY PEAK HEATING
SUNDAY...WHILE THE GFS LAGS BELOW A THIRD OF AN INCH. BOTH MODELS
INDICATE SOME WEAK BROAD SCALE ASCENT ASSOCIATED WITH EMBEDDED
ENERGY IN THE FLOW AND THE SUB TROP JET ACROSS THE DESERT SOUTHWEST.
WITH DRY LOW LAYERS THE FOCUS WILL REMAIN ACROSS THE RIDGETOPS WHERE
MOST OF THE ACTION WILL JUST BE BUILDING CU. BETTER MOISTURE GETS
PUSHED UP THE EASTERN DIVIDE IN THE WAKE OF AN FRONT RANGE FRONT. SO
THE BEST CHANCES SEEM TO BE ALONG THE CENTRAL DIVIDE MOUNTAINS WHERE
SMALL POPS WILL BE IN PLACE. TEMPERATURES REMAIN NEAR TO ABOVE
NORMAL.
.LONG TERM...(SUNDAY NIGHT THROUGH FRIDAY)
ISSUED AT 415 AM MDT SAT JUN 22 2013
.SUNDAY NIGHT AND MONDAY...
FORCING QUICKLY WANES SUNDAY NIGHT LEAVING DRY CONDITIONS GOING INTO
MONDAY. THETA SURFACES BEGIN TO SHOW STRONG MOISTURE ADVECTION INTO
THE WEST COAST WHICH WILL GRADUALLY BE PICKED UP BY THE SOUTHWEST
FLOW AND DIRECTED TOWARD OUR CWA. HOWEVER THIS WILL NOT BE UNTIL THE
MID WEEK PERIOD SO MONDAY LOOKS TO AGAIN REMAIN MAINLY PRECIPITATION
FREE. WARM TEMPERATURES AND A BATCH OF MID LEVEL COOLING LOOKS TO
BRING SOME GOOD AFTERNOON MIXING IN THIS WARM AIRMASS. OVERALL THE
GRADIENT NOT QUITE AS STRONG AS THE PAST FEW DAYS BUT AFTERNOON
GUSTY WINDS OVER 25 MPH MAY WIDESPREAD AND BRING ANOTHER ROUND OF
CRITICAL FIRE WEATHER CONDITIONS.
TUESDAY THROUGH FRIDAY...
THE WESTERLIES RETREAT NORTHWARD ON TUESDAY...GUSTY AFTERNOON
WINDS MAY STILL EXIST ACROSS THE NORTH. BUT LESS WIND CAN BE
EXPECTED ACROSS THE SOUTH. FOR WEDENESDAY AND BEYOND...STRONG HIGH
PRESSURE BECOMES ANCHORED OVER THE FOUR CORNER STATES. LESS WIND
BUT TURNING HOTTER ACROSS THE ENTIRE AREA. ISOLATED HIGH BASED
THUNDERSTORMS MAY POP OVER THE COLORADO HIGH COUNTRY...BUT THIS
WILL BE DEPENDENT ON HOW MOISTURE WILL TRAPPED BENEATH THE
SUBTROPICAL HIGH.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON)
ISSUED AT 1134 AM MDT SAT JUN 22 2013
AFTERNOON GUSTS OF 25-30KTS ARE EXPECTED OTHERWISE VFR PREVAILS.
THERE IS A 20 PERCENT CHANCE OF -TSRA NORTH OF KVEL TIL 03Z THIS
EVENING.
&&
.FIRE WEATHER...
ISSUED AT 415 AM SAT JUN 22 2013
FIRE ZONE 201 FUELS HAVE BEEN UPGRADED TO CRITICAL...HOWEVER
HUMIDITY VALUES STAY ABOVE RED FLAG CRITERIA. WILL NOT HOIST A RED
FLAG WARNING FOR ZONE 201. FOR THE REMAINDER OF THE AREA...DEEP
MIXED LAYER AND A STRONG JUNE SUN MEANS ANOTHER DAY OF GUSTY WINDS
AT MANY SPOTS.
GUSTY WINDS AND LOW HUMIDITY WILL CONTINUE THROUGH THE REMAINDER
OF THE WEEKEND...THE QUESTION BEING WHETHER THE WINDS WILL SURPASS
CRITICAL CRITERIA ON SUNDAY. WINDS AT THIS POINT LOOK TO DECREASE
UNDER HEADLINE THRESHOLDS THOUGH LOCAL GUSTS ARE EXPECTED IN THE
AFTERNOON.
ON MONDAY...NEGATIVELY TILTED TROUGH SWIPES NORTHERN REGION OF CWA
AND MAY INCREASE WINDS DURING THE DAY. WILL BE MONITORING THIS
THROUGH THE WEEKEND.
TEMPERATURES LATE NEXT WEEK ASSOCIATED WITH THE BUILDING RIDGE
WILL INCREASE WELL ABOVE NORMAL.
&&
.GJT WATCHES/WARNINGS/ADVISORIES...
CO...RED FLAG WARNING UNTIL 9 PM MDT THIS EVENING FOR COZ200-202-203-
207-290>293.
UT...RED FLAG WARNING UNTIL 9 PM MDT THIS EVENING FOR UTZ486-487.
&&
$$
SHORT TERM...PF/15
LONG TERM...15/PF
AVIATION...JDC
FIRE WEATHER...CC
AREA FORECAST DISCUSSION
NWS DENVER/BOULDER CO
1120 AM MDT SAT JUN 22 2013
.UPDATE...
&&
.SHORT TERM...TEMPERATURES ON THE PLAINS RUNNING BEHIND YESTERDAY AT
THIS TIME BY 5-10 DEG F...AND 2-6 DEG F BEHIND IN THE HIGH COUNTRY.
THEREFORE THE COOLER MAX TEMPERATURES ALREADY IN THE FCST LOOK
GOOD. LOW CLOUDS BLANKETING MUCH OF NORTHEAST COLORADO EARLIER
THIS MORNING AND STILL OUT NEAR THE NORTHEAST CORNER PARTLY TO
BLAME FOR THE COOLER START TO THE DAY...EVEN WITH A VERY WARM
SOUTHWEST FLOW ALOFT. THIS SWLY FLOW WILL LIKELY MIX DOWN TO THE
SFC PRODUCING GUSTY SWLY WINDS IN THE MTN VALLEYS AND ALONG THE
SRN FOOTHILLS OVER THE NEXT 1-3 HOURS. DEWPTS ALREADY QUITE LOW IN
THESE AREAS...SO RED FLAG WARNING FOR THE MTN VALLEYS AND SRN
FOOTHILLS LOOKS JUSTIFIED. WARNING BEGINS AT NOON MDT. MEANWHILE
HAVE REACHED CONVECTIVE TEMPERATURES IN THE NORTHERN FOOTHILLS AND
ALONG THE SPINE OF THE CONTINENTAL DIVIDE WHERE CU AND TCU ARE
BEGINNING TO FORM. SHOULD SEE THIS PROGRESS CONTINUE THROUGH THE
AFTERNOON AS MID-LEVEL MOISTURE FILTERS IN FROM UTAH AROUND THE
BOTTOM SIDE OF AN UPPER TROUGH APPROACHING WRN WYOMING. HAVE
INCREASED AFTERNOON POPS SLIGHTLY FOR THE NRN MTN RANGES AND NRN
FOOTHILLS...HOWEVER STORMS IN THIS AREA LIKELY TO PRODUCE MORE
GUSTY WIND THAN WETTING RAINFALL THRU EARLY THIS EVENING. ON THE
PLAINS...PLENTY OF CIN OUT THERE NOW...EVEN WITH SFC DEWPOINTS IN
THE MID/UPPER 50S EAST OF A FORT COLLINS-TO-LIMON LINE. MOISTURE
LOOKS SHALLOW ON LAPS AND RUC SOUNDINGS AND CROSS SECTIONS.
THROUGH THE AFTERNOON THE WEST SIDE OF THIS MOISTURE IS PROGGED TO
MIGRATE EAST WITH DRIER SOUTHWESTERLY WINDS COMING OFF THE
FOOTHILLS AND PALMER DIVIDE. BUT ITS OUT ACROSS THE NORTHEAST
CORNER OF THE STATE WHERE LOW-LEVEL MOISTURE WILL HANG TIGHT WITH
SFC BASED CAPES UP AROUND 2500 J/KG BY AROUND 00Z/SUN. SPC HAS
THIS AREA UNDER A SLIGHT RISK FOR SVR T-STORMS. MAY TAKE MOST OF
THE AFTERNOON FOR IT TO DEVELOP OUT THERE WITH ALL OF THE
CIN...PROBABLY NOT UNTIL AFTER 21Z OR 22Z. DAMAGING T-STORM WINDS
AND LARGE HAIL MAIN THREATS. SHOULD SEE MOST OF THIS CONVECTION
WRAPPING UP BY 06Z TONIGHT.
.AVIATION...VFR CONDITIONS ANTICIPATED AT DENVER AREA AIRPORTS
TODAY AND TONIGHT. ISOLATED HIGH BASED AND MOSTLY DRY T-STORMS
DRIFTING OFF THE FOOTHILLS LATE THIS AFTERNOON MAY PRODUCE SOME
GUSTY WINDS...GENERALLY LESS THAN 30 KTS. LITTLE OR NO CHANCE OF
WETTING RAINFALL. SKIES CLEAR OVERNIGHT. LIGHT AND VARIABLE WINDS
AT THIS HOURS EXPECTED TO BECOME SOUTH-SOUTHWEST LATTER THIS
AFTERNOON AT 7-14KTS...THEN DRAINAGE FLOW OVERNIGHT AT LIGHTER
SPEEDS.
&&
.FIRE WEATHER...RED FLAG WARNING GOES INTO EFFECT AT 12 PM MDT
AND RUNS UNTIL 8 PM MDT THIS EVENING FOR COLORADO FIREWEATHER
ZONES 211-213-214-216 AND 241. GUSTY WINDS...LOW RELATIVE
HUMIDITIES AND DRY FUELS MAIN REASONS FOR THE WARNING.
&&
.HYDROLOGY...STRONG STORMS OVER THE FAR NORTHEAST PLAINS THIS
EVENING COULD DROP 1-2 INCHES OF RAIN IN A SHORT PERIOD OF TIME.
OTHERWISE HEAVY RAIN OR FLOODING NOT EXPECTED ELSEWHERE.
&&
.PREV DISCUSSION... /ISSUED 339 AM MDT SAT JUN 22 2013/
SHORT TERM...MAIN CONCERN AGAIN TODAY WILL BE THE SEVERE
POTENTIAL OVER THE PLAINS AND FIRE WEATHER CONCERNS OVER THE
SOUTHERN PORTION OF CWA.
LITTLE CHANGE IN THE SYNOPTIC PATTERN WITH UPPER TROF OVER IDAHO
AND MODEST SOUTHWEST FLOW OVER COLORADO. AT THE SURFACE...LOW
PRESSURE OVER FAR EAST CENTRAL COLORADO WHILE SEVERAL SURGES FROM
LAST NIGHT CONVECTION HAS REPLENISHED THE LOW LEVEL MOISTURE.
SURFACE DEWPOINTS HAVE INCREASED INTO THE MID 40S TO MID 50S WHILE
INTEGRATED PW VALUES ARE AROUND 6 TENTHS OF AN INCH OVER THE FRONT
RANGE WHICH IS JUST SLIGHTLY DOWNWARD FROM 24 HOURS AGO. THIS
MOISTURE WILL AGAIN FLUSH OUT AS THE DRIER AIR MIXES DOWN. THE
QUESTION WILL BE WHERE WILL THE BOUNDARY END UP WITH THE DRIER AIR
TO THE SOUTHWEST AND MORE MOIST AIR TO THE NORTHEAST. APPEARS
STORMS MAY FIRE A BIT MORE TO THE SOUTHWEST THIS AFTERNOON VS.
FRIDAY AND BEST GUESS WOULD BE ALONG A LINE FROM LIMON TO GREELEY
AND POINTS NORTH AND EAST. LATEST WRF SIMULATED IMAGERY SHOWING
SOMETHING SIMILAR TO ABOVE SCENARIO.
STORMS THAT DO DEVELOP WILL PROBABLY BECOME SEVERE WITH SURFACE
BASED CAPES FROM 2000-3000J/KG AND MODEST MID LEVEL FLOW. FURTHER
WEST...WITH THE DRIER AIR MIXING DOWN THERE MAY BE SOME HIGH BASED
SHOWERS WITH GUSTY WINDS THE MAIN THREAT. AS LIKE THIS
NIGHT...EXPECT OUTFLOW BOUNDARIES TO USHER IN HIGHER LOW LEVEL
MOISTURE BY SUNDAY MORNING.
LONG TERM...SW FLOW ALOFT WILL REMAIN OVER THE AREA SUN AND MON.
APPEARS ANOTHER WEAK COOL FNT WILL AFFECT NERN CO ON SUN WITH ESE
LOW LVL FLOW WHICH SHOULD ALLOW DEEPER MOISTURE TO STAY IN PLACE
ACROSS THE PLAINS AND POSSIBLY THE NRN FOOTHILLS. EXPECT THERE
WILL BE A DENVER CYCLONE BY AFTN WITH A CONVERGENCE ZONE SETTING
ALONG OR JUST EAST OF THE FRONT RANGE URBAN CORRIDOR. WITH A
FAVORABLE SHEAR PROFILE IN PLACE AND CAPES BY AFTN RANGING FM
1500-2500 J/KG COULD SEE AN ACTIVE AFTN AND EVENING OVER THE NERN
PLAINS. IN THE MTNS AND HIGHER VALLEYS DRIER AIR WILL REMAIN
PLACE ALTHOUGH COULD SEE A FEW HIGH BASED STORMS EAST OF THE
DIVIDE. FIRE DANGER WILL CONTINUE CRITICAL IN THE HIGHER VALLEYS
AND OVER PARK COUNTY. AS FOR HIGHS TEMPS SHOULD BE A FEW DEGREES
COOLER OVER NERN CO WITH READINGS MAINLY IN THE 80S.
BY MON THE LOW LEVEL FLOW WILL BECOME MORE SLY ON MON OVER NERN CO
WHICH WILL SCOUR OUT LOW LEVEL MOISTURE EXCEPT OVER THE FAR NERN
PLAINS. THERE WILL BE SOME SFC CONVERGENCE AND HIGHER CAPES
NORTHEAST OF A NEW RAYMER TO FORT MORGAN TO LIMON LINE SO MAY SEE
A SLIGHT CHC OF TSTMS BY MID TO LATE AFTN. ELSEWHERE APPEARS A DRY
AIRMASS WILL BE IN PLACE SO WILL KEEP THE REST OF THE AREA DRY.
ONCE AGAIN FIRE DANGER WILL REMAIN VERY HIGH OVER THE HIGHER
VALLEYS AND PARK COUNTY MON AFTN. HIGHS ON MON OVER NERN CO WILL
RISE BACK INTO THE LOWER TO MID 90S.
FOR TUE THE FLOW ALOFT WILL BECOME MORE WLY AS AN UPPER LEVEL
RIDGE BEGINS TO BUILD OVER THE SRN ROCKIES WITH A VERY DRY AIRMASS
IN PLACE. FIRE DANGER WILL REMAIN VERY HIGH ALTHOUGH LOW LEVEL
WINDS MAY NOT BE QUITE AS GUSTY. HIGHS ON TUE WILL RISE INTO THE
90S ACROSS NERN CO. BY WED AND THU AN UPPER LEVEL HIGH WILL BE
CENTERED OVER SWRN CO WITH WLY FLOW ALOFT ACROSS NRN CO. MOISTURE
BOTH DAYS STILL LOOKS MEAGER SO WILL KEEP FCST DRY. HIGHS BOTH
DAYS OVER NERN CO LOOK TO BE IN THE 95 TO 100 DEGREE RANGE.
BY FRI BOTH THE ECMWF AND GFS MOVE THE UPPER LEVEL HIGH A LITTLE
FURTHER WEST WHICH ALLOWS FOR THE FLOW ALOFT TO BECOME MORE NWLY.
BOTH MODELS TRY TO ENTRAIN SOME SUB TROPICAL MOISTURE INTO THE
FLOW AS A WEAK COOL FNT MOVES INTO NERN CO. THUS THIS MAY LEAD TO
A SLIGHT CHC OF AFTN AND EVENING TSTMS OVER THE HIGHER TERRAIN AND
THE PLAINS.
AVIATION...NORTHWEST SURFACE WINDS TO GRADUALLY TURN NORTHEAST
AND EAST BY EARLY AFTERNOON. THEN SOUTHWEST WINDS WILL BEGIN TO
MIX DOWN BY LATE AFTERNOON. THUNDERSTORMS MAY GET A LITTLE CLOSER
TODAY BUT STILL THINK MOST OF THE ACTIVITY WILL BE EAST AND
NORTHEAST OF THE TERMINALS AND WON`T MENTION FOR NOW.
FIRE WEATHER...A REPEAT PERFORMANCE THIS AFTERNOON WITH RED FLAG
CONDITIONS AGAIN ACROSS MTN VALLEYS...PARK COUNTY AND PALMER
DIVIDE. ZONE 216 IS BORDERLINE FOR THE GUSTY WINDS BUT LOOKS LIKE
SHOULD BE A LITTLE STRONGER THAN FRIDAY AND WILL ADD TO THE RED
FLAG WARNINGS.
HYDROLOGY...STRONG STORMS OVER THE FAR NORTHEAST PLAINS COULD
DROP 1-2 INCHES OF RAIN IN A SHORT PERIOD OF TIME. FURTHER
WEST...VERY LITTLE RAINFALL EXPECTED OVER THE FRONT RANGE.
&&
.BOU WATCHES/WARNINGS/ADVISORIES...
RED FLAG WARNING UNTIL 8 PM MDT THIS EVENING FOR COZ211-213-214-
216-241.
&&
$$
SHORT TERM...BAKER/ENTREKIN
LONG TERM....RPK
AVIATION...BAKER/ENTREKIN
AREA FORECAST DISCUSSION
NWS ALBANY NY
659 PM EDT SAT JUN 22 2013
.SYNOPSIS...
WARM AND HUMID CONDITIONS WILL CONTINUE THROUGH THE REMAINDER OF
THE WEEKEND AND INTO THE START OF THE NEW WORK WEEK. THERE WILL BE
THE CHANCE FOR MAINLY AFTERNOON AND EVENING SHOWERS AND
THUNDERSTORMS UNDER VARIABLE CLOUDS.
&&
.NEAR TERM /THROUGH SUNDAY/...
AS OF 645 PM EDT...THE TREND DURING THE PAST HOUR OR SO IS THAT
SCATTERED SHOWERS HAVE BECOME LESS SCATTERED. A WEAK DISTURBANCE HAS
SET THEM OFF...BUT THE RUC ANALYSIS ASSOCIATED WITH THIS SHORT WAVE
APPEARS TO BE WEAKENING.
THE HRRR AND 18Z NAM INDICATE THIS WILL INDEED BE THE CASE.
HOWEVER...THE WFOWRF HAS INDICATED OTHERWISE...THAT THESE SHOWERS
WILL BECOME ENHANCED AND PROBABLY CONTAIN THUNDER AS WELL.
HOWEVER...LOOKING AT SPC PARAMETERS IT APPEARS THAT THERE WILL NOT
BE AN INCREASE IN MOISTURE OR INSTABILITY (ACTUALLY SHOULD BE
LOWERING WITH LOSS OF HEATING). FORCING APPEARS RATHER MINIMAL AT
THIS TIME WITH THE BEST LOW LEVEL JET CORE ACROSS THE ST LAWRENCE
VALLEY. BELIEVE THE WFOWRF IS PROBABLY NOT CORRECT BUT IT IS
CERTAINLY POSSIBLE.
FOR THIS UPDATE FOLLOWED THE PREVIOUS FORECASTER`S THINKING ALTHOUGH
I TRIMMED DOWN POPS A LITTLE AND ONLY INCLUDE A CHANCE OF THUNDER
SINCE THERE HAVE BEEN VIRTUALLY NO CGS OVER OUR REGION SO FAR.
CLOUDS WILL CONTINUE TO INCREASE FOR AWHILE AND ISOLATED SHOWERS
SHOULD MAKE IT INTO THE CAPITAL REGION AND EVEN SOUTH...BUT AGAIN
NOT EVERYONE WILL HAVE SEE A SHOWER.
FOR THE REST OF THE DAYLIGHT HOURS...LOOK FOR MOST OF US TO REMAIN
RAIN FREE BUT SHOWER IS POSSIBLE FROM THE CAPITAL DISTRICT
NORTHWARD. IT WILL REMAIN SOMEWHAT HUMID AND WARM WITH TEMPERATURES
ONLY VERY SLOW TO FALL BACK INTO THE MID AND UPPER 70S. A SOUTH WIND
WILL AVERAGE 5 TO 10 MPH.
CLOUD COVER FORECAST TONIGHT WILL BE PROBLEMATIC AS CONVECTIVE
DEBRIS ALONG WITH A INCREASE IN LOW LEVEL MOISTURE COULD RESULT IN
TWO CLOUD LAYERS /THE BEST POTENTIAL ALONG AND NORTH OF I90/. SO FOR
NOW...WE WILL CALL IT PT-MOCLOUDY AND KEEP OVERNIGHT LOW TEMPS A BIT
MILD AND CLOSER THE MET MOS VALUES WHICH IS IN AGREEMENT WITH THE
HOURLY LAV/LAMP. LOWS FOR LOWS IN THE 60S...UPPER 60S LOCALLY IN THE
TRI-CITY REGION. ALL INDICATIONS THOUGH POINT TO AN INCREASE IN
CLOUD COVER THIS EVENING...DECREASING OVERNIGHT. DID TWEAK THE CLOUD
COVER A BIT AS WELL ESPECIALLY DURING THE OVERNIGHT.
&&
.SHORT TERM /SUNDAY NIGHT THROUGH MONDAY NIGHT/...
WITH A LACK OF STRONG FORCING MECHANISMS IN THE SHORT TERM
COMBINING WITH INCREASE WARMTH AND HUMID CONDITIONS AROUND THE
PERIPHERY OF BERMUDA HIGH...THE CHANCE FOR MAINLY AFTERNOON AND
EARLY EVENING SHOWERS/THUNDERSTORMS. LAPSE RATES ARE MARGINAL WITH
VALUES LESS THAN 6/KM IN THE H850-500 LAYER...HOWEVER...SBCAPES
ARE EXPECTED TO RANGE BETWEEN 1K-2K J/KG DURING THE PEAK HEATING AS
TEMPERATURES CLIMB WELL INTO THE 80S FOR MANY LOCATIONS. OVERNIGHT
LOWS WILL GENERALLY RANGE IN THE 60S...BUT WOULD NOT BE RULE OUT
OUR FIRST 70 DEGREE OVERNIGHT LOW DURING THE NEXT COUPLE OF
NIGHTS.
&&
.LONG TERM /TUESDAY THROUGH SATURDAY/...
THE WEATHER PATTERN LOOKS UNSETTLED THROUGHOUT THE EXTENDED PERIOD.
THE WEAK RIDGE TO OUR SOUTH LOOKS TO SLOWLY RETROGRADE
WESTWARD...STRENGTHENING AS IT SETS UP SHOP OVER THE WESTERN CONUS
BY LATE IN THE WEEK. IN RESPONSE...IT LOOKS AS IF A LONG WAVE TROUGH
WILL SLOWLY DIG INTO THE EASTERN CONUS.
THE DEVIL IN THE DETAILS ARE HARD TO PINPOINT AT THIS TIME. WHAT WE
DO KNOW IS THAT TEMPERATURES WILL SLOWLY COOL DOWN...AND BY NEXT
WEEKEND...SHOULD BE RUNNING SLIGHTLY BELOW NORMAL. THE TRICKIER PART
IS TIMING SPECIFIC DISTURBANCES THAT WILL PROVIDE A FOCUS FOR SHOWER
AND THUNDERSTORMS.
IT LOOKS AS IF TUESDAY WE WILL STILL BE IN A SOUPY AIR MASS WITH
STILL NO GOOD TRIGGER OTHER THAN DIURNAL HEATING TO SPARK SHOWERS
AND THUNDERSTORMS. SO ON THAT DAY...WENT WITH SLIGHT CHANCES OF
SHOWERS EARLY...LOW POPS (30 PERCENT CHANCES) OF SHOWERS AND
THUNDERSTORMS DURING THE AFTERNOON AND EVENING HOURS. TEMPERATURES
WILL CLIMB WELL INTO THE 80S...POSSIBLY TOUCHING 90 IN THE VALLEY
AREAS SOUTH OF ALBANY. IT WILL BE RATHER HUMID AS WELL.
WEDNESDAY...A WEAK COLD FRONTS LOOKS TO CROSS THE REGION SOMETIME
DURING THE DAY...TRIGGERING AGAIN MAINLY LATE AFTERNOON AND EVENING
THUNDERSTORMS. TEMPERATURES LOOK SLIGHTLY COOLER BUT STILL
WARM...WELL INTO THE 80S MOST PLACES AND STILL A BIT HUMID.
A VERY WEAK HIGH PRESSURE MIGHT BRIEFLY BUILD IN WEDNESDAY NIGHT
INTO EARLY THURSDAY SO WHILE WE CANNOT ENTIRELY RULE OUT SHOWERS (20
POPS) WE BELIEVE THIS COULD BE A BRIEF "DRIER" PERIOD WITH SLIGHTLY
LOWER HUMIDITY.
LATER THURSDAY...ALL MODELS INDICATE SURFACE LOW PRESSURE AT THE
SURFACE AND ALOFT WILL HEAD FROM THE GREAT LAKES TOWARD OUR REGION.
THIS SYSTEM LOOKS TO BE THE ONE THAT REALLY BEGINS TO BUCKLE THE
RIDGE IN THE EAST. THIS SYSTEM COULD BRING AN ORGANIZED AREA OF
SHOWERS AND EMBEDDED THUNDERSTORMS (POSSIBLY EVEN A MULTIPLE
CONVECTIVE SYSTEM - MCS) OUR WAY LATE THURSDAY INTO FRIDAY.
HIGHS BOTH THURSDAY AND FRIDAY LOOK TO BE IN THE MID TO UPPER 70S
ACROSS THE HIGHER TERRAIN...AROUND 80 IN THE VALLEYS. IF EITHER DAY
TURNS OUT TO BE A WASHOUT (A POSSIBILITY)...TEMPERATURES WOULD BE A
LITTLE LOWER.
THEN...YET ANOTHER LOW PRESSURE AREA AT THE SURFACE AND ALOFT COULD
BRING YET ANOTHER ROUND OF DISTURBED WEATHER ON FRIDAY INTO EARLY
SATURDAY.
WHILE THE 12Z EUROPEAN HAS A SURFACE LOW MOVING ON BY
SATURDAY...LOW PRESSURE ALOFT LINGERS ACROSS THE GREAT LAKES WHICH
WOULD COOL THE MID AND UPPER LEVELS OF THE ATMOSPHERE TO KEEP THE
THREAT OF ADDITIONAL SHOWERS AND THUNDERSTORMS AROUND...ESPECIALLY
SATURDAY AFTERNOON.
HIGHS SATURDAY MIGHT BE MAINLY IN THE 70S...EXCEPT LOWER 80S ACROSS
THE MID HUDSON VALLEY.
OVERNIGHT LOWS THROUGHOUT THE PERIOD WILL GENERALLY BE IN THE
60S...EXCEPT SOME 50S ACROSS THE HIGHER TERRAIN BY FRIDAY NIGHT.
&&
.AVIATION /00Z SUNDAY THROUGH THURSDAY/...
A NEARLY STATIONARY FRONTAL BOUNDARY WILL REMAIN LOCATED JUST NORTH
OF THE UNITED STATES/CANADIAN BORDER. A WEAK DISTURBANCE WILL PASS
ALONG THIS BOUNDARY LATER TODAY.
FLYING CONDITIONS ARE CURRENTLY VFR WITH MAINLY JUST SOME SCT HIGH
CLOUDS OVER THE AREA. VFR CONDITIONS LOOK TO CONTINUE THROUGH THE
AFTERNOON AND INTO THE EVENING...AS LOWER TO MID LEVEL CLOUDS START
TO INCREASE AS THE WEAK DISTURBANCE MOVES ALONG THE BOUNDARY TO OUR
NORTH. A FEW PASSING SHOWERS AND AN ISOLD THUNDERSTORM ARE POSSIBLE
BY THIS EVENING INTO TONIGHT...ALTHOUGH SINCE COVERAGE WILL BE
FAIRLY LIMITED...WE WILL LIMIT MENTION TO JUST VCSH FOR THE NORTHERN
TERMINALS OF KGFL/KALB/KPSF.
DUE TO THE CLOUDS AND A LIGHT SOUTHERLY BREEZE OVERNIGHT...NO FOG IS
ANTICIPATED AT KGFL/KALB. CLOUDS MAY BE THINNER AT KPSF/KPOU AND IF
WINDS LIGHTEN UP ENOUGH AFTER MIDNIGHT...THEN SOME BR/FG MAY BE
POSSIBLE. FOR NOW...WILL LIMIT TO JUST MVFR DUE TO THE UNCERTAINTY
ON TIMING/EXTENT AFTER ABOUT 07Z.
AFTER SUNRISE...ANY FOG SHOULD DISSIPATE AND VFR CONDITIONS WILL BE
IN PLACE FOR ALL TERMINALS. CLOUDS SHOULD SCT OUT FOR THE REMAINDER
OF THE MORNING AND EARLY AFTN...ALTHOUGH ADDITIONAL SHOWERS ARE
POSSIBLE LATER ON SUNDAY.
OUTLOOK...
SUN PM-THU...MAINLY VFR. CHC -TSRA/-SHRA MAINLY DURING THE AFTN
INTO THE EVNG.
&&
.FIRE WEATHER...
AS HIGHER LOWER LEVEL MOISTURE CONTINUES TO ADVECT INTO THE
REGION...OVERNIGHT DEW FORMATION ALONG WITH THE CHANCE FOR
ADDITIONAL SHOWERS AND THUNDERSTORMS WILL KEEP THE LOW LEVELS
RATHER MOIST THE NEXT FEW DAYS.
&&
.HYDROLOGY...
OVERALL...FLOWS WILL CONTINUE TO GRADUALLY LOWER CLOSER TO
SEASONAL NORMAL LEVELS OVER THE NEXT 5 DAYS.
ISOLATED TO SCATTERED SHOWERS AND THUNDERSTORMS ARE EXPECTED
THROUGH EARLY NEXT WEEK...HOWEVER WIDESPREAD RAINFALL IS NOT
ANTICIPATED AT THIS TIME...AND NOT ALL LOCATIONS WILL RECEIVE THE
RAINFALL.
AS THE AIR MASS GETS MORE HUMID...SLOW MOVING THUNDERSTORMS COULD
PRODUCE A QUICK INCH OR SO OF RAINFALL WITH HIGHER THAN NORMAL
PWAT VALUES OVER THE HSA. SOME POOR DRAINAGE FLOODING OF LOW LYING
AREAS...AND PONDING OF WATER ON ROADWAYS WILL BE POSSIBLE ANY DAY.
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...BGM
NEAR TERM...HWJIV/BGM
SHORT TERM...BGM
LONG TERM...HWJIV
AVIATION...FRUGIS
FIRE WEATHER...BGM
HYDROLOGY...BGM
AREA FORECAST DISCUSSION
NWS ALBANY NY
355 PM EDT SAT JUN 22 2013
.SYNOPSIS...
WARM AND HUMID CONDITIONS WILL CONTINUE THROUGH THE REMAINDER OF
THE WEEKEND AND INTO THE START OF THE NEW WORK WEEK. THERE WILL BE
THE CHANCE FOR MAINLY AFTERNOON AND EVENING SHOWERS AND
THUNDERSTORMS UNDER VARIABLE CLOUDS.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
REGIONAL RADARS THIS AFTERNOON SHOW A WEAK COMPLEX OF CONVECTION
ACROSS LAKE ONTARIO WITH MINIMAL CG/S PER THE NLDN. THIS
APPEARS...PER THE H2O VAPOR LOOP...TO BE ASSOCIATED WITH A WEAK
SHORT WAVE THAT THE LATEST RAP MODEL SUGGESTS WILL MOVE ACROSS THE
NORTHERN 2/3RDS OF THE REGION THROUGH THIS EVENING. WE WILL PLACE
POPS AOA 20-30% AS THE LEADING EDGE WOULD APPROACH AT THE TIME
WHEN THE SUN IS CLOSE TO SETTING FURTHER REDUCING INSTABILITY. IN
FACT...LATEST RUN OF THE HRRR AND 4KM SPC WRF REFLECTIVITIES
SUGGEST THIS INITIAL BATCH WOULD WEAKEN AND ATTEMPT TO REDEVELOP
NORTH OF I90 OVERNIGHT. THIS SECOND SURGE WOULD BE ON THE LEADING
EDGE OF ADDITIONAL WARMTH AND HUMIDITY AS SEEN IN THE THETA-E
FIELDS. HOWEVER...FORCING APPEARS RATHER MINIMAL AT THIS TIME WITH
THE BEST LOW LEVEL JET CORE ACROSS THE ST LAWRENCE VALLEY.
CLOUD COVER FORECAST WILL BE PROBLEMATIC AS CONVECTIVE DEBRIS
ALONG WITH A INCREASE IN LOW LEVEL MOISTURE COULD RESULT IN TWO
CLOUD LAYERS /THE BEST POTENTIAL ALONG AND NORTH OF I90/. SO FOR
NOW...WE WILL CALL IT PT-MOCLOUDY AND KEEP OVERNIGHT LOW TEMPS A
BIT MILD AND CLOSER THE MET MOS VALUES WHICH IS IN AGREEMENT WITH
THE HOURLY LAV/LAMP.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH MONDAY NIGHT/...
WITH A LACK OF STRONG FORCING MECHANISMS IN THE SHORT TERM
COMBINING WITH INCREASE WARMTH AND HUMID CONDITIONS AROUND THE
PERIPHERY OF BERMUDA HIGH...THE CHANCE FOR MAINLY AFTERNOON AND
EARLY EVENING SHOWERS/THUNDERSTORMS. LAPSE RATES ARE MARGINAL WITH
VALUES LESS THAN 6/KM IN THE H850-500 LAYER...HOWEVER...SBCAPES
ARE EXPECTED TO RANGE BETWEEN 1K-2K J/KG DURING THE PEAK HEATING AS
TEMPERATURES CLIMB WELL INTO THE 80S FOR MANY LOCATIONS. OVERNIGHT
LOWS WILL GENERALLY RANGE IN THE 60S...BUT WOULD NOT BE RULE OUT
OUR FIRST 70 DEGREE OVERNIGHT LOW DURING THE NEXT COUPLE OF
NIGHTS.
&&
.LONG TERM /TUESDAY THROUGH SATURDAY/...
THE WEATHER PATTERN LOOKS UNSETTLED THROUGHOUT THE EXTENDED PERIOD.
THE WEAK RIDGE TO OUR SOUTH LOOKS TO SLOWLY RETROGRADE
WESTWARD...STRENGTHENING AS IT SETS UP SHOP OVER THE WESTERN CONUS
BY LATE IN THE WEEK. IN RESPONSE...IT LOOKS AS IF A LONG WAVE TROUGH
WILL SLOWLY DIG INTO THE EASTERN CONUS.
THE DEVIL IN THE DETAILS ARE HARD TO PINPOINT AT THIS TIME. WHAT WE
DO KNOW IS THAT TEMPERATURES WILL SLOWLY COOL DOWN...AND BY NEXT
WEEKEND...SHOULD BE RUNNING SLIGHTLY BELOW NORMAL. THE TRICKIER PART
IS TIMING SPECIFIC DISTURBANCES THAT WILL PROVIDE A FOCUS FOR SHOWER
AND THUNDERSTORMS.
IT LOOKS AS IF TUESDAY WE WILL STILL BE IN A SOUPY AIR MASS WITH
STILL NO GOOD TRIGGER OTHER THAN DIURNAL HEATING TO SPARK SHOWERS
AND THUNDERSTORMS. SO ON THAT DAY...WENT WITH SLIGHT CHANCES OF
SHOWERS EARLY...LOW POPS (30 PERCENT CHANCES) OF SHOWERS AND
THUNDERSTORMS DURING THE AFTERNOON AND EVENING HOURS. TEMPERATURES
WILL CLIMB WELL INTO THE 80S...POSSIBLY TOUCHING 90 IN THE VALLEY
AREAS SOUTH OF ALBANY. IT WILL BE RATHER HUMID AS WELL.
WEDNESDAY...A WEAK COLD FRONTS LOOKS TO CROSS THE REGION SOMETIME
DURING THE DAY...TRIGGERING AGAIN MAINLY LATE AFTERNOON AND EVENING
THUNDERSTORMS. TEMPERATURES LOOK SLIGHTLY COOLER BUT STILL
WARM...WELL INTO THE 80S MOST PLACES AND STILL A BIT HUMID.
A VERY WEAK HIGH PRESSURE MIGHT BRIEFLY BUILD IN WEDNESDAY NIGHT
INTO EARLY THURSDAY SO WHILE WE CANNOT ENTIRELY RULE OUT SHOWERS (20
POPS) WE BELIEVE THIS COULD BE A BRIEF "DRIER" PERIOD WITH SLIGHTLY
LOWER HUMIDITY.
LATER THURSDAY...ALL MODELS INDICATE SURFACE LOW PRESSURE AT THE
SURFACE AND ALOFT WILL HEAD FROM THE GREAT LAKES TOWARD OUR REGION.
THIS SYSTEM LOOKS TO BE THE ONE THAT REALLY BEGINS TO BUCKLE THE
RIDGE IN THE EAST. THIS SYSTEM COULD BRING AN ORGANIZED AREA OF
SHOWERS AND EMBEDDED THUNDERSTORMS (POSSIBLY EVEN A MULTIPLE
CONVECTIVE SYSTEM - MCS) OUR WAY LATE THURSDAY INTO FRIDAY.
HIGHS BOTH THURSDAY AND FRIDAY LOOK TO BE IN THE MID TO UPPER 70S
ACROSS THE HIGHER TERRAIN...AROUND 80 IN THE VALLEYS. IF EITHER DAY
TURNS OUT TO BE A WASHOUT (A POSSIBILITY)...TEMPERATURES WOULD BE A
LITTLE LOWER.
THEN...YET ANOTHER LOW PRESSURE AREA AT THE SURFACE AND ALOFT COULD
BRING YET ANOTHER ROUND OF DISTURBED WEATHER ON FRIDAY INTO EARLY
SATURDAY.
WHILE THE 12Z EUROPEAN HAS A SURFACE LOW MOVING ON BY
SATURDAY...LOW PRESSURE ALOFT LINGERS ACROSS THE GREAT LAKES WHICH
WOULD COOL THE MID AND UPPER LEVELS OF THE ATMOSPHERE TO KEEP THE
THREAT OF ADDITIONAL SHOWERS AND THUNDERSTORMS AROUND...ESPECIALLY
SATURDAY AFTERNOON.
HIGHS SATURDAY MIGHT BE MAINLY IN THE 70S...EXCEPT LOWER 80S ACROSS
THE MID HUDSON VALLEY.
OVERNIGHT LOWS THROUGHOUT THE PERIOD WILL GENERALLY BE IN THE
60S...EXCEPT SOME 50S ACROSS THE HIGHER TERRAIN BY FRIDAY NIGHT.
&&
.AVIATION /19Z SATURDAY THROUGH THURSDAY/...
A NEARLY STATIONARY FRONTAL BOUNDARY WILL REMAIN LOCATED JUST NORTH
OF THE UNITED STATES/CANADIAN BORDER. A WEAK DISTURBANCE WILL PASS
ALONG THIS BOUNDARY LATER TODAY.
FLYING CONDITIONS ARE CURRENTLY VFR WITH MAINLY JUST SOME SCT HIGH
CLOUDS OVER THE AREA. VFR CONDITIONS LOOK TO CONTINUE THROUGH THE
AFTERNOON AND INTO THE EVENING...AS LOWER TO MID LEVEL CLOUDS START
TO INCREASE AS THE WEAK DISTURBANCE MOVES ALONG THE BOUNDARY TO OUR
NORTH. A FEW PASSING SHOWERS AND AN ISOLD THUNDERSTORM ARE POSSIBLE
BY THIS EVENING INTO TONIGHT...ALTHOUGH SINCE COVERAGE WILL BE
FAIRLY LIMITED...WE WILL LIMIT MENTION TO JUST VCSH FOR THE NORTHERN
TERMINALS OF KGFL/KALB/KPSF.
DUE TO THE CLOUDS AND A LIGHT SOUTHERLY BREEZE OVERNIGHT...NO FOG IS
ANTICIPATED AT KGFL/KALB. CLOUDS MAY BE THINNER AT KPSF/KPOU AND IF
WINDS LIGHTEN UP ENOUGH AFTER MIDNIGHT...THEN SOME BR/FG MAY BE
POSSIBLE. FOR NOW...WILL LIMIT TO JUST MVFR DUE TO THE UNCERTAINTY
ON TIMING/EXTENT AFTER ABOUT 07Z.
AFTER SUNRISE...ANY FOG SHOULD DISSIPATE AND VFR CONDITIONS WILL BE
IN PLACE FOR ALL TERMINALS. CLOUDS SHOULD SCT OUT FOR THE REMAINDER
OF THE MORNING AND EARLY AFTN...ALTHOUGH ADDITIONAL SHOWERS ARE
POSSIBLE LATER ON SUNDAY.
OUTLOOK...
SUN PM-THU...MAINLY VFR. CHC -TSRA/-SHRA MAINLY DURING THE AFTN
INTO THE EVNG.
&&
.FIRE WEATHER...
AS HIGHER LOWER LEVEL MOISTURE CONTINUES TO ADVECT INTO THE
REGION...OVERNIGHT DEW FORMATION ALONG WITH THE CHANCE FOR
ADDITIONAL SHOWERS AND THUNDERSTORMS WILL KEEP THE LOW LEVELS
RATHER MOIST THE NEXT FEW DAYS.
&&
.HYDROLOGY...
OVERALL...FLOWS WILL CONTINUE TO GRADUALLY LOWER CLOSER TO
SEASONAL NORMAL LEVELS OVER THE NEXT 5 DAYS.
ISOLATED TO SCATTERED SHOWERS AND THUNDERSTORMS ARE EXPECTED
THROUGH EARLY NEXT WEEK...HOWEVER WIDESPREAD RAINFALL IS NOT
ANTICIPATED AT THIS TIME...AND NOT ALL LOCATIONS WILL RECEIVE THE
RAINFALL.
AS THE AIR MASS GETS MORE HUMID...SLOW MOVING THUNDERSTORMS COULD
PRODUCE A QUICK INCH OR SO OF RAINFALL WITH HIGHER THAN NORMAL
PWAT VALUES OVER THE HSA. SOME POOR DRAINAGE FLOODING OF LOW LYING
AREAS...AND PONDING OF WATER ON ROADWAYS WILL BE POSSIBLE ANY DAY.
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...BGM
NEAR TERM...BGM
SHORT TERM...BGM
LONG TERM...HWJIV
AVIATION...FRUGIS
FIRE WEATHER...BGM
HYDROLOGY...BGM
FOR THE LATEST UPDATES...PLEASE VISIT OUR WEBPAGE AT
WWW.WEATHER.GOV/ALBANY
AREA FORECAST DISCUSSION
NWS MIAMI FL
137 PM EDT SAT JUN 22 2013
.AVIATION...RADAR SHOWS QUITE A BIT OF SHOWER ACTIVITY OVER THE NW
BAHAMAS AT THIS TIME. THERE HAS BEEN A FEW TSTORMS AS WELL. AS THE
TROUGH ASSOCIATED WITH THIS ACTIVITY MOVES WEST, WE EXPECT
SHOWERS TO MOVE INTO SE FLORIDA TONIGHT, ESPECIALLY AFTER
MIDNIGHT. A FEW THUNDERSTORMS WILL BE POSSIBLE AS WELL AS IT WILL
BE SUFFICIENTLY UNSTABLE ALONG WITH PWATS INCREASING TO AROUND 2
INCHES. GIVEN THESE FORECASTED TRENDS, HAVE ADDED VCTS TO ALL EAST
COAST TAF SITES BEGINNING AFTER MIDNIGHT AND CONTINUING THROUGH
SUNDAY. FOR KAPF, ACTIVITY IS EXPECTED TO REMAIN EAST OF THE
TERMINAL UNTIL AFTER ABOUT NOON ON SUNDAY, SO HELD OFF VCTS THERE
UNTIL 16Z SUNDAY. BRIEF IFR WILL BE POSSIBLE WHERE HEAVIER
SHRA/TSRA OCCURS, THOUGH PREVAILING CONDITIONS ARE EXPECTED TO
REMAIN VFR. THANKS FOR COLLABORATION CWSU MIAMI. /GREGORIA
&&
.PREV DISCUSSION... /ISSUED 1044 AM EDT SAT JUN 22 2013/
UPDATE...
FORECAST WAS UPDATED FOR THE SHORT TERM AND THE REMAINDER OF THE
WEEKEND. LATEST GUIDANCE SUGGESTS THAT FOR TODAY MAINLY ISOLATED
SHOWERS OR ISOLATED THUNDERSTORMS EXPECTED ACROSS THE ATLANTIC
WATERS AND EASTERN HALF OF THE PENINSULA WHILE FOR THE WESTERN
HALF THIS AFTERNOON MORE SCATTERED SHOWER AND THUNDERSTORM
ACTIVITY IS EXPECTED. THE FORECAST WAS ALSO UPDATED TO REFLECT A
CHANCE OF CONVECTION TONIGHT ACROSS THE ATLANTIC WATERS AND THE
EASTERN THIRD OF THE PENINSULA AS A LOW LEVEL TROUGH CONTINUES
TO MOVE WESTWARD ACROSS THE NORTHWEST BAHAMAS AND INTO THE LOCAL
ATLANTIC WATERS. THE LOW LEVEL TROUGH IS FORECAST TO REMAIN MOVING
WESTWARD ACROSS THE REGION TONIGHT THROUGH SUNDAY WITH A CHANCE
OF SHOWERS AND THUNDERSTORMS THROUGH THAT PERIOD.
60
PREV DISCUSSION... /ISSUED 648 AM EDT SAT JUN 22 2013/
AVIATION...
QUIET WEATHER IS EXPECTED FOR THE TAF PERIOD WITH VFR CONDITIONS
PREVAILING. THERE IS SOME TROPICAL MOISTURE TRYING TO MAKE ITS WAY
INTO SOUTH FLORIDA, BUT IS HAVING TROUBLE DUE TO THE DRY AIR IN
PLACE IN THE UPPER LEVELS. THERE IS STILL A SLIGHT CHANCE OF A
SHOWER OR A THUNDERSTORM TODAY, BUT TOO UNCERTAIN TO MAKE ANY
REFERENCE IN THE TAFS AT THIS TIME.
PREV DISCUSSION... /ISSUED 256 AM EDT SAT JUN 22 2013/
SHORT TERM (TODAY THROUGH MONDAY)...
DEEP LAYER RIDGE IS BEGINNING TO SHIFT NORTH AND THE 00Z MFL
SOUNDING WAS SHOWING A DEEP EASTERLY FLOW AT 5 TO 10 KNOTS. THE
TROPICAL WAVE THAT WAS PRODUCING NUMEROUS SHOWERS AND SOME
THUNDERSTORMS A FEW DAYS AGO HAS BEEN FIGHTING SOME DRY AIR THAT
SURROUNDS IT AND HAS NOW MOVED INTO THE CENTRAL CARIBBEAN LOSING MOST
OF ITS CONVECTION. THE NORTHERN PORTION OF THE WAVE HAS BECOME A
TROUGH OVER THE CENTRAL BAHAMAS AND HAS SCATTERED SHOWERS AND FEW
THUNDERSTORMS ASSOCIATED WITH IT. THE TROUGH HAS SLOWED ITS
FORWARD MOVEMENT AND MUCH DRIER AIR ALOFT IS AHEAD OF IT ACROSS
THE WESTERN BAHAMAS AND SOUTH FLORIDA. IN FACT, THE SOUNDING LAST
EVENING SHOWED THE PWAT HAD LOWERED TO 1.13 INCHES WHICH IS BELOW
THE 25TH PERCENTILE FOR MID-LATE JUNE AND THERE WERE ONLY A FEW
STORMS LATE YESTERDAY AS A RESULT OF THIS DRY AIR INTRUSION. DUE TO
THE FACT THE ACTUAL WAVE WILL NOW REMAIN WELL TO OUR SOUTH AND THE
TROUGH AXIS HAS SLOWED, THE HRRR IS SHOWING VIRTUALLY NO ACTION
ALONG THE EAST COAST TODAY AND WITH THE DEEP EAST TO WEST STEERING
FLOW DEPICTS SHOWERS AND STORMS DEVELOPING WELL INLAND AFTER 18Z
AND THEN INCREASING AS THEY MOVE TOWARDS THE COLLIER COUNTY COAST
AND THE LAKE REGION. THEREFORE, WILL LOWER THE POPS TO A SILENT 10
PERCENT OVER THE EAST METRO REGION AND TREND UP TO LOW END
SCATTERED FARTHER INLAND. ALL OF THE GLOBAL MODELS ARE IN GOOD
AGREEMENT WITH THIS SCENARIO AND ALSO INCREASE MOISTURE ON SUNDAY
AS THE TROUGH AXIS APPROACHES. THE MOISTURE WILL STILL BE AROUND
ON MONDAY BUT MODEL FORECAST SOUNDINGS ONLY SHOW AN INCREASE IN
PWAT TO NEAR AVERAGE FOR THIS TIME OF YEAR SO SIGNIFICANT RAINFALL
IS NOT ANTICIPATED.
LONG TERM (MONDAY NIGHT THROUGH FRIDAY)...
THE DEEP LAYER RIDGE WILL BECOME NEARLY STATIONARY ACROSS NORTH
FLORIDA FOR MUCH OF THE UPCOMING WEEK SO THE BEST CHANCES FOR RAIN
WILL BE DURING THE LATE NIGHT AND EARLY MORNING ALONG THE EAST
COAST AND IN THE AFTERNOON TO EARLY EVENING FOR THE INTERIOR AND
SOUTHWEST COAST. MOISTURE INCREASE WILL AGAIN NOT BE PLENTIFUL SO
ONLY ISOLATED AREAS OF HEAVIER RAIN CAN BE EXPECTED MAINLY WHERE
THE AFTERNOON THUNDERSTORMS CAN DEVELOP.
MARINE...
WIND SPEEDS WILL FLUCTUATE THROUGH THE PERIOD BUT REMAIN IN AN
EAST TO SOUTHEAST DIRECTION SO SEAS WILL BE AT 4 FEET OR LESS.
FIRE WEATHER...
NO PROBLEMS OR CONCERNS WITH AMPLE LOW LEVEL MOISTURE REMAINING IN PLACE.
&&
.PRELIMINARY POINT TEMPS/POPS...
WEST PALM BEACH 89 78 88 78 / 20 30 40 20
FORT LAUDERDALE 88 79 88 80 / 20 30 40 20
MIAMI 89 78 88 79 / 20 30 40 20
NAPLES 92 74 92 75 / 40 30 50 20
&&
.MFL WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
AM...NONE.
GM...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS LINCOLN IL
1258 PM CDT SAT JUN 22 2013
.DISCUSSION...
ISSUED 1044 AM CDT SAT JUN 22 2013
CONVECTIVE CHANCES REMAIN MAIN CONCERN TODAY. PRIMARY OUTFLOW
BOUNDARY IS CURRENTLY PUSHING SOUTH INTO THE NORTHEAST CWA WITH
SCATTERED THUNDERSTORMS DEVELOPING BEHIND THIS FEATURE. THIS
SHOULD CONTINUE INTO EARLY AFTERNOON AS THE BOUNDARY SLIPS
SOUTH...HOWEVER IT SHOULD EVENTUALLY SLOW AND STALL /UNLESS MORE
VIGOROUS CONVECTION KEEPS COLD POOL GOING/ AS IT ENCOUNTERS 10-20
KT SOUTHWEST SYNOPTIC FLOW. SCATTERED SHOWERS AND SPRINKLES
AFFECTING PARTS OF THE WESTERN CWA OUT OF A MID LEVEL DECK AND
FEEL THIS AREA COULD FILL IN WITH SCATTERED TSTMS WITH DAYTIME
HEATING. 12Z ILX SOUNDING SHOWED HIGH CAPES AND VERY WEAK WINDS
ALOFT...WHICH COMBINED WITH A 2 INCH P/W MAKES HEAVY RAIN RATES
AND FREQUENT LIGHTNING MAIN THREATS WITH STORMS TODAY. ISOLATED
PULSE TYPE NEAR SVR POSSIBLE DUE TO PRECIP LOADING BUT LOW BULK
SHEAR MAKES MORE ORGANIZED SVR UNLIKELY. HAVE INCREASED POPS TO LOW
CHANCE OVER MOST OF THE CWA WITH LIKELY POPS IN THE NE CWA WHERE
MORE SIGNIFICANT OUTFLOW BOUNDARY SHIFTS THROUGH NEXT FEW HOURS.
SUNNIER LOCATIONS SHOULD GET INTO THE LOWER 90S AND WITH DEWPOINTS
IN THE LOWER 70S PEAK HEAT INDICES NEAR 100 POSSIBLE.
&&
.AVIATION...
ISSUED 1258 PM CDT SAT JUN 22 2013
OUTFLOW BOUNDARY PUSHING THROUGH THE EASTERN TERMINAL WILL PRODUCE
HIGHEST COVERAGE TSRA EARLY THIS AFTERNOON AFFECTING CMI AND
POSSIBLY DEC. VERY HEAVY RAIN RATES BRINGING VSBYS DOWN BELOW 1SM
IN HEAVIER STORMS. OTHERWISE ONLY ISOLATED ACTIVITY EXPECTED
FARTHER WEST AND HAVE CARRIED VCTS THROUGH AFTERNOON. AFTER THIS
SYSTEM PUSHES SOUTH NOT MUCH FOCUS FOR ADDITIONAL STORMS INTO
SUNDAY MORNING AND MAINLY VFR SKIES EXPECTED. LATER FORECASTS WILL
ADDRESS POSSIBLE MVFR FOG THAT COULD DEVELOP LATE TONIGHT IN
LIGHTER WIND REGIME. SOUTHWEST WINDS WILL PICK UP OVER 10 KTS
AFTER 14Z/SUN.
25
&&
.PREV DISCUSSION...
ISSUED 250 AM CDT SAT JUN 22 2013
2 AM SATELLITE IMAGERY AND RADAR DATA SHOWING A PAIR OF MCS
SYSTEMS MERGING FROM SOUTH DAKOTA EASTWARD INTO SOUTHERN
WISCONSIN. EASTERN END OF THE LINE OF STORMS HAS MADE A SOUTHWARD
PUSH INTO NORTHEAST ILLINOIS...WITH THIS PART OF THE MCS BECOMING
THE DOMINANT ONE AS LIGHTNING DIMINISHES OVER SOUTHERN MINNESOTA.
LINGERING BOUNDARY FROM THE STORMS IN OUR AREA YESTERDAY WRAPS
AROUND THE SOUTHWEST AND SOUTHEAST PARTS OF THE FORECAST AREA.
STILL SEEING A FEW SPRINKLES IN THE FAR SOUTHEAST CWA WITH THIS
BOUNDARY.
FORECAST CHALLENGES FOR THIS PACKAGE GENERALLY REVOLVE AROUND
TIMING OF THUNDERSTORM CHANCES...AS WELL AS THE ONGOING HEAT AND
HUMIDITY.
SHORT TERM...TODAY THROUGH MONDAY...
MODELS ARE STRUGGLING TO GET A HANDLE ON THE CURRENT SITUATION...
WITH THE HRRR AND THE REGIONAL CANADIAN MODEL CLOSEST TO REALITY.
NEITHER OF THESE MODELS SHOW THE STORMS MAKING IT AS FAR SOUTH AS
OUR FORECAST AREA...BUT AS THE MCS FROM YESTERDAY SHOWED...THAT
OUTCOME IS DEFINITELY NOT GUARANTEED. WILL INCLUDE SOME ISOLATED
THUNDERSTORM MENTION IN THE NORTHEAST THIRD OF THE CWA THIS
MORNING...BETWEEN THIS LINE AND POTENTIALLY SOME DEVELOPMENT ALONG
THE OUTFLOW BOUNDARY...WITH AROUND 30 PERCENT CHANCES ACROSS THE
NORTHEAST DURING THE AFTERNOON. HAVE MENTIONED ISOLATED STORMS
ELSEWHERE THIS AFTERNOON AND EARLY EVENING.
FOCUS CONTINUES TO BE WITH TIMING OF VARIOUS MCS FEATURES THIS
WEEKEND. DEVELOPMENT ACROSS IOWA/MINNESOTA ON SUNDAY EXPECTED TO
EXTEND SOUTHWEST INTO MISSOURI...BUT ONLY THE NAM BRINGS ANY OF IT
THIS FAR EAST BY MONDAY MORNING. HAVE LIMITED ANY 30 PERCENT OR
HIGHER POPS TO THE FAR NORTHWEST LATE SUNDAY NIGHT... WITH MORE
WIDESPREAD CHANCES MONDAY. THE ECMWF AND CANADIAN MODELS SHOW THE
MCS SPREADING OVER THE FORECAST AREA... WHILE THE NAM AND GFS
SHUNT IT MORE TO THE NORTHEAST. SEVERE WEATHER POTENTIAL APPEARS
TO INCREASE BY MONDAY...MAINLY IN THE NORTHWEST CWA.
HAVE KEPT HIGH TEMPERATURES RIGHT AROUND 90 DEGREES FOR THE NEXT
FEW DAYS...WITH HEAT INDEX VALUES IN THE MID TO UPPER 90S. WILL
HAVE TO KEEP AN EYE ON HIGHS FOR MONDAY THOUGH...AS THEY COULD BE
LOWER IF THIS MCS DOES PAN OUT.
LONG TERM...TUESDAY THROUGH FRIDAY...
BROAD EAST-WEST RIDGE EXPECTED TO COVER THE SOUTH HALF OF THE
CONUS MUCH OF THE WEEK...WITH THE MAIN STORM TRACK ACROSS THE
NORTHERN STATES. MCS TRACKS REMAINS THE CONCERN AND ALTHOUGH MANY
OF THEM ARE FURTHER NORTH...LEFTOVER OUTFLOWS MAKE IT DIFFICULT TO
PIN DOWN ANY DRY PERIODS WITH ANY CERTAINTY. HIGHEST POPS FROM
WEDNESDAY NIGHT TO FRIDAY ARE TIED INTO PASSAGE OF A COLD FRONT...
WHICH MAY TAKE UNTIL EARLY FRIDAY TO FULLY PASS THE REGION AS THE
UPPER RIDGING BUILDS ACROSS THE ROCKIES AND PUTS THE MIDWEST MORE
OF A TROUGH. THIS PARTICULAR PATTERN WOULD SHOW THE HEAT FINALLY
BREAKING ON FRIDAY...WITH COOLER CONDITIONS NEXT WEEKEND.
GEELHART
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS WICHITA KS
306 PM CDT SAT JUN 22 2013
.SHORT TERM...(THIS EVENING THROUGH TUESDAY)
ISSUED AT 306 PM CDT SAT JUN 22 2013
FORECAST HIGHLIGHTS FOCUS AROUND HOT AND WINDY WEATHER CONTINUING
THROUGH MID WEEK...THUNDERSTORM CHANCES LATE SUN AFTERNOON-NIGHT
OVER CENTRAL KS AND AGAIN THU-THU NIGHT AREAWIDE...AND A COOLING
TREND BY LATE WEEK/NEXT WEEKEND.
APPROACHING SHORTWAVE ENERGY SHOULD INITIATE A FEW THUNDERSTORMS
OVER WESTERN KS LATE THIS AFTERNOON ALONG A SHARPENING DRYLINE. LAST
3 RUNS OF THE HRRR HAVE ALLUDED TO THIS. NOT OUT OF THE REALM OF
POSSIBILITY THAT SOME OF THIS ACTIVITY COULD GET INTO RUSSELL AND
BARTON COUNTIES BETWEEN 8 PM AND MIDNIGHT. HOWEVER...SUSPECT WEAK
FORCING IN CONCERT WITH WARM MID-LEVEL TEMPERATURES/INCREASING CINH
WILL LIKELY DISSIPATE THIS ACTIVITY BEFORE REACHING WESTERN
CORRIDOR. ADDITIONAL ACTIVITY WILL LIKELY AFFECT NEBRASKA AND
POSSIBLY FAR NORTHERN KS OVERNIGHT...BUT WILL LIKELY REMAIN NORTH OF
THE FORECAST AREA.
OTHERWISE...SHORTWAVE ENERGY PROGRESSING ACROSS THE NORTHERN PLAINS
WILL ALLOW A COLD FRONT TO APPROACH CENTRAL KS SUNDAY. THE INCREASED
CONVERGENCE AT PEAK HEATING COULD ALLOW A FEW ISOLATED STORMS TO
FIRE ALONG THE FRONT SUNDAY LATE AFTERNOON...POSSIBLY AFFECTING
LOCATIONS NORTH OF A GREAT BEND-SALINA LINE. HOWEVER...GIVEN WEAK
FORCING AT PEAK HEATING...THINKING THE MORE PROBABLE SCENARIO IS
CLUSTER OF THUNDERSTORMS DEVELOPING OVER NORTHWEST KS/SOUTHWEST NE
AND PROPAGATING EAST/SOUTHEAST INTO CENTRAL KS AFTER DARK. GIVEN
NAM`S PLACEMENT OF FRONT...THINKING LOCATIONS NORTH OF GREAT
BEND-SALINA HAVE A DECENT CHANCE OF SEEING MOISTURE...ALONG WITH
POTENTIAL FOR A STRONG/SEVERE FORWARD PROPAGATING MCS CARRYING AN
ISOLATED DAMAGING WIND THREAT.
FRONT LIFTS NORTH FOR MON-TUE...EFFECTIVELY SHUTTING DOWN
PRECIPITATION CHANCES AND CONTINUING THE WINDY AND HOT WEATHER.
WINDS WILL LIKELY FLIRT WITH WIND ADVISORY CRITERIA ONCE AGAIN SUN
AND MON...AND POSSIBLY TUE AS WELL. FURTHERMORE...PER THE
GFS...CANNOT COMPLETELY RULE OUT A STRAY THUNDERSTORMS GETTING INTO
RUSSELL/BARTON COUNTIES TUE EVENING...BUT ONCE AGAIN SUSPECT BETTER
CHANCES WILL REMAIN WEST/NORTHWEST.
ADK
&&
.LONG TERM...(WEDNESDAY THROUGH SATURDAY)
ISSUED AT 306 PM CDT SAT JUN 22 2013
THE UPPER RIDGE IS PROGGED TO BUILD IN EARNEST ACROSS THE WESTERN
CONUS LATE NEXT WEEK. THE HIGHER AMPLITUDE FLOW REGIME WILL
EVENTUALLY ALLOW A SIGNIFICANT UPPER TROF TO DROP SOUTHEAST ACROSS
THE GREAT LAKES WHICH WILL DEVELOP INTO AN EASTERN CONUS LONGWAVE
BY NEXT WEEKEND. THE RESULT FOR KANSAS WILL BE A CONTINUATION OF
THE BREEZY AND HOT WEATHER THROUGH MID-WEEK WITH A COLD FRONTAL
PASSAGE AND SOMEWHAT COOLER OR LESS HOT CONDITIONS BY
FRIDAY/SATURDAY. LATEST PROGGED LOW LEVEL THICKNESS VALUES/THERMAL
FIELDS WOULD SUPPORT HOTTER MAXS AHEAD OF THE FRONTAL PASSAGE FOR
WEDNESDAY AND THURSDAY...WITH MAXS AT OR ABOVE THE CENTURY MARK
FOR LOCATIONS ALONG/WEST OF I-135. THE GFS LATEST FRONTAL TIMING
COULD ALLOW FOR A VERY HOT BUBBLE OF COMPRESSED AIR ON THE
WESTERLY COMPONENT FLOW ACROSS MUCH OF SOUTHERN KANSAS ON THURSDAY
AFTERNOON. SO FOR NOW HAVE MADE A SLIGHT UP-TWEAK TO THE LOADED
INITIALIZATION WHICH IS ALSO ABOVE GMOS VALUES. WILL CONTINUE TO
CARRY SLIGHT CHANCE POPS THURSDAY INTO EARLY FRIDAY...THOUGH
FORCING REMAINS RATHER WEAK AND LIKELY TIED TO FRONTAL CONVERGENCE
AND MAINLY DIURNALLY DRIVEN CONVECTION WITH CARRYOVER INTO
THURSDAY NIGHT EARLY FRIDAY MORNING.
DARMOFAL
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON)
ISSUED AT 1213 PM CDT SAT JUN 22 2013
VFR CONDITIONS WILL PREVAIL THROUGH THE PERIOD. ONLY AVIATION
CONCERN WILL BE GUSTY WINDS THIS AFTERNOON AND INTO THE EVENING.
WINDS FROM A SOUTHERLY DIRECTION AT SPEEDS IN A 30 TO 35 MPH RANGE
CAN BE EXPECTED WITH GUSTS TO NEAR 40 MPH AT
RSL...GBD...HUT...SLN...ICT...AND AAO.
CHANCE
&&
.PRELIMINARY POINT TEMPS/POPS...
WICHITA-KICT 75 96 74 95 / 10 10 10 10
HUTCHINSON 75 98 74 97 / 10 10 20 10
NEWTON 74 96 74 95 / 10 10 10 10
ELDORADO 74 93 74 93 / 0 0 10 10
WINFIELD-KWLD 75 94 74 94 / 0 0 10 10
RUSSELL 75 99 70 98 / 10 20 40 10
GREAT BEND 75 100 71 98 / 10 10 30 10
SALINA 75 98 72 97 / 10 10 40 10
MCPHERSON 75 98 74 96 / 10 10 20 10
COFFEYVILLE 75 92 74 92 / 10 0 10 10
CHANUTE 74 92 74 91 / 10 0 10 10
IOLA 74 92 74 91 / 10 0 10 10
PARSONS-KPPF 75 92 74 91 / 10 0 10 10
&&
.ICT WATCHES/WARNINGS/ADVISORIES...
WIND ADVISORY UNTIL 8 PM CDT THIS EVENING FOR KSZ032-033-047-048-
050-067-082-091.
&&
$$
AREA FORECAST DISCUSSION...UPDATED
NWS TOPEKA KS
1241 PM CDT SAT JUN 22 2013
.UPDATE...
ISSUED AT 1233 PM CDT SAT JUN 22 2013
UPDATED THE AFTERNOON GRIDS TO REMOVE THUNDER AND EVENTUALLY
END ALL PRECIP BY AROUND 19Z. TEMPERATURES...WINDS AND HEAT
INDICES NORTH CENTRAL ALTHOUGH DELAYED...STILL EXPECTED TO RECOVER
THROUGH THE MIDDLE AND LATE AFTERNOON HOURS. WILL LIKELY NEED
ANOTHER UPDATE IN THE NEXT ONE TO TWO HOURS TO REMOVE ALL MENTION
OF PRECIP.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 343 AM CDT SAT JUN 22 2013
LARGE COMPLEX OF RAIN AND THUNDERSTORMS CONTINUES TO MARCH EASTWARD
ACROSS MUCH OF NORTH AND EAST NEBRASKA AND POINTS NE. SOUTHERN
PROGRESS OF THE OUTFLOW HAS SLOWED SOMEWHAT THE PAST HOUR OR SO.
SHORTWAVE TROF NOTED IN WV IMAGERY OVER EASTERN KS ATTM...BUT IS
PRODUCING ONLY CLOUDS SO FAR AS IT PASSES. EVENING SOUNDING AT TOP
SHOWED STEEP LAPSE RATES IN THE 750 TO 550 MB LAYER...HOWEVER CAP IS
STRONG BELOW 700MB AND COLUMN IS DRY THROUGH ABOUT 400MB. ONLY
GUIDANCE THAT SUGGESTS PRECIP THIS MORNING HAS BEEN OUT WEST WITH
THE HRRR FOR SEVERAL RUNS...ALL OTHERS REMAIN DRY. WILL CARRY A
SILENT POP WEST OF MANHATTAN FOR A FEW HOURS THIS MORNING. COULD
GET A BRIEF BREAK NORTH FROM SOME OF THE OUTFLOW FROM THE
NORTH...BUT EXPECT THAT WOULD BE SHORT LIVED. HIGHS STILL EXPECTED
INTO THE LOWER TO MIDDLE 90S WITH HEAT INDICES RUNNING AROUND 100
ALONG THE KS RIVER VALLEY. WINDS BECOME QUITE BREEZY OUT OF THE
SOUTH AS YOU GO WESTWARD...WITH SUSTAINED AFTERNOON WINDS AROUND 30
WITH GUSTS 35-40 POSSIBLE. WILL MONITOR TRENDS FOR WIND ADVISORY
BUT IS BORDERLINE AT THIS TIME. OVERNIGHT LOWS EXPECTED ON THE WARM
SIDE AGAIN IN THE MIDDLE 70S. 67
.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 343 AM CDT SAT JUN 22 2013
MID RANGE AND EXTENDED FORECAST (SUNDAY THROUGH FRIDAY)...
VERY LITTLE CHANGE IN THIS FORECAST PACKAGE AS MODELS ARE STILL
CONSISTENT IN SHOWING A LARGE SCALE RIDGING PATTERN ACROSS THE
SOUTHEASTERN PORTION OF THE CONUS THROUGH THE WEEKEND...WITH A
PACIFIC TROUGH OVER THE WEST COAST. LIGHT SOUTHWEST FLOW WILL BE
PRESENT OVER THE ROCKY MOUNTAINS UP THROUGH THE NORTHERN
PLAINS...WITH THE CENTRAL PLAINS BEING ON THE EASTERN FRINGE OF THE
BETTER FLOW. EXPECT WARM TEMPERATURES TO CONTINUE FOR SUNDAY...WITH
A PRETTY DECENT CHANCE FOR RAIN SUNDAY NIGHT AS A DISTURBANCE WITHIN
THE SOUTHWESTERLY FLOW ALOFT WILL TRIGGER A ROUND OF THUNDERSTORMS
ACROSS SOUTHERN NEBRASKA AND NORTHERN KANSAS. THE BEST CHANCE FOR
RAIN WILL BE ALONG THE KS/NE BORDER...WITH DECREASING CHANCES
FURTHER SOUTH ALONG INTERSTATE 70.
EXPECT LITTLE IN THE WAY OF CONVECTIVE CHANCES AFTER THE SUNDAY
NIGHT ROUND OF THUNDERSTORMS. ECMWF HAS BEEN CONSISTENT IN
PREDICTING THE FOUR CORNERS MID LEVEL RIDGE TO SET UP BY MID
WEEK...WHICH WILL KEEP TEMPERATURES IN THE AREA WARM THROUGH THE
EXTENDED PERIOD. TEMPERATURES GENERALLY WILL REMAIN IN THE LOWER TO
MID 90S ACROSS EASTERN KANSAS THROUGH THE EXTENDED PERIOD...WITH
TEMPS REACHING THE MID TO UPPER 90S IN WESTERN KANSAS. THE NEXT
CHANCES FOR RAIN WILL BE RATHER MINIMAL AS A BOUNDARY LOOKS TO SLIDE
INTO THE AREA IN THE THURSDAY/FRIDAY TIME FRAME. THIS BOUNDARY WOULD
BE THE FOCUS FOR ANY POTENTIAL CONVECTION DURING THAT TIME PERIOD.
MADE VIRTUALLY NO CHANGE TO THE FORECAST FOR THE LATE PART OF THE
WEEK FOR THESE POTENTIAL SHOWERS.
JL
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON)
ISSUED AT 1233 PM CDT SAT JUN 22 2013
VFR CONDITIONS WILL PERSIST THROUGH THE PERIOD AS THIS AFTERNOONS
CONVECTION/SHOWERS TO THE WEST OF THE TERMINALS DISSIPATES AND TONIGHTS
CONVECTION REMAINS NORTH AND WEST OF THE TERMINALS AS WELL THROUGH
THE PERIOD. GUSTY SOUTH WINDS THIS AFTERNOON WILL DECREASE TO
11-14KTS AFT 02Z...BEFORE INCREASING AGAIN AFT 14Z.
&&
.TOP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...63
SHORT TERM...CRAVEN
LONG TERM...LEIGHTON
AVIATION...63
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
426 PM EDT SAT JUN 22 2013
.SHORT TERM...(THIS EVENING THROUGH SUNDAY)
ISSUED AT 423 PM EDT SAT JUN 22 2013
WV IMAGERY AND RUC ANALYSIS INDICATED A MID/UPPER LEVEL TROUGH FROM
ALBERTA INTO THE NRN ROCKIES AND A RIDGE OVER THE CNTRL GREAT LAKES
RESULTING IN SW FLOW FROM THE PLAINS THROUGH THE UPPER MS VALLEY.
THE MOST PROMINENT UPSTREAM SHORTWAVE TROUGH WAS MOVING THROUGH WRN
WYOMING. WIDESPREAD LOW LEVEL MOISTURE AND CLOUDS PREVAILED NORTH OF
A WARM FRONT EXTENDING FROM SE MN THROUGH CNTRL WI. TO THE SOUTH OF
THE FRONT...TEMPS OVER ERN IA HAD CLIMBED INTO THE MID AND UPPER 80S
WITH DEWPOINTS INTO THE LOWER 70S.
TONIGHT...AS THE MID LEVEL RIDGE BUILDS TO THE EAST...THE SW FLOW
PATTERN WILL ALLOW THE SFC-850 MB WARM FRONT TO PUSH TO THE NORTH.
ALTHOUGH CONVECTION IS EXPECTED TO REDEVELOP ALONG OR AHEAD OF THE
WARM FRONT THIS EVENING.....UNCERTAINTY WITH THE TIMING/POSITION OF
ANY UPSTREAM SHRTWVS AND THE EVOLUTION OF CONVECTION IS
HIGH. WITH THE FOCUS FOR MOISTURE/LOW LEVEL THETA-E ADVECTION
SHIFTING FROM THE UPPER MS VALLEY TOWARD THE CWA...POPS INCREASE
INTO THE WRN CWA AND ACROSS UPPER MICHIGAN BUT ARE STILL LIMITED TO
CHANCE CATEGORY. SINCE MUCAPE VALUES ARE ONLY EXPECTED IN THE
400-800 J/KG RANGE...ONLY ISOLD TSRA WERE MENTIONED. POTENTIAL FOR
STRONG OR SEVERE STORMS SHOULD REMAIN FARTHER SOUTH NEAR THE GREATER
INSTABILITY.
SUNDAY...AS THE WY SHRTWV LIFTS INTO THE NRN PLAINS A STRENGTHENING
SFC LOW OVER THE ERN DAKOTAS WILL BRING INCREASING SRLY FLOW INTO
THE WRN LAKES AND SHOULD FINALLY PUSH THE WARM FRONT NORTH OF UPPER
MI. HOWEVER...CINH WILL ALSO INCREASE WITH 700 MB TEMPS INTO THE
10C-12C RANGE. SO...TEMPS WILL CLIMB WELL ABOVE NORMAL INTO THE
MID/UPPER 80S AND CONVECTION POTENTIAL WILL BE LIMITED OVER THE
CNTRL AND EAST. HOWEVER...SHRA/TSRA WILL INCREASE AGAIN BY MIDDAY
SUN INTO SUN AFTERNOON AS MODELS CONTINUE TO SUGGEST A WEAK
SHRTWV/IMPULSE COULD BRUSH MAINLY THE WRN CWA. MLCAPE VALUES INTO
THE 1500-2000 J/KG RANGE COMBINED WITH 0-6KM SHEAR VALUES IN THE
30-40 KT RANGE COULD SUPPORT SOME STRONGER AND POSSIBLY SEVERE
STORMS.
.LONG TERM...(SUNDAY NIGHT THROUGH SATURDAY)
ISSUED AT 423 PM EDT SAT JUN 22 2013
UPPER AIR PATTERN SUNDAY NIGHT INDICATES A DEEPER TROUGH LIFTING
INTO SCNTRL CANADA WITH RIDGING CENTERED OVER OHIO VALLEY. SFC WARM
FRONT SHOULD BE VCNTY OF UPR MICHIGAN/LK SUPERIOR. H85 FRONT ALSO
SHOULD BE MAINLY NORTH OF CWA. FORECAST WILL ASSUME THAT IS GOING TO
BE THE CASE AS LAST COUPLE DAYS...SFC WARM FRONT HAS REMAINED
FARTHER SOUTH THAN FORECAST THANKS TO TSRA AND ASSOCIATED RAIN
COOLED OUTFLOW. DO THINK FRONT WILL HAVE BETTER SHOT OF MAKING IT
NORTH OF UPR MICHIGAN BY SUNDAY NIGHT DUE TO SW FLOW AHEAD OF
STRONGER SHORTWAVE ALOFT. BASED ON INITIAL FOCUS REGION FOR
SHRA/TSRA AND H7 WINDS/FORWARD PROPAGATING CORFIDI VECTORS AND
850-300MB THICKNESS...EXPECT CHANCES OF SHRA/TSRA SUNDAY NIGHT TO
MAINLY BE OVER WESTERN THIRD OF UPR MICHIGAN AND ACROSS LK
SUPERIOR ON EDGE OF H7 CAPPING TIED TO ELEVATED MIXED LAYER /EML/.
AS MENTIONED IN SHORT TERM DISCUSSION...BASED ON AVAILABLE
INSTABILITY AND DEEP LAYER SHEAR...THERE WILL BE POTENTIAL FOR STRONG
OR SEVERE STORMS SUNDAY EVENING OVER THE WEST. NAM/ECMWF FITS THIS
EXPECTATION THE BEST WHILE THE GEM-NH AND GFS SEEM TO SHOW QPF TOO
FAR EAST INTO THE CAPPED AREA. THOSE IDEAS WOULD HAVE BETTER CHANCE
OF VERIFYING IF THE SFC-H85 FRONTS END UP FARTHER SOUTH THAN FORECAST.
CHANCES FOR SHRA/TSRA ON MONDAY LIKELY HIGHEST DURING THE MORNING
AND HIGHEST OVER THE EASTERN CWA ON EDGE OF CAPPING THAT WILL BE
BEING SHUNTED TO THE EAST AND SOUTH AT THAT TIME AS H85 WINDS VEER
MORE WESTERLY. WILD CARD FOR MONDAY IS IF TAIL OF SHORTWAVE AND
ASSOCIATED HEIGHT FALLS MOVING ACROSS NORTHERN LK SUPERIOR ARE
SUFFICIENT ENOUGH TO TRIGGER OTHER SHRA/TSRA ON EDGE OF CAPPING AND
MUCAPE GRADIENT JUST UPSTREAM AND/OR JUST SOUTH OF UPR MICHIGAN. A
PRETTY LOW CHANCE OF THIS...BUT IF IT WOULD HAPPEN THEN THERE IS
POSSIBILITY OF SHRA/TSRA COMPLEX IMPACTING PARTS OF CWA ON MONDAY
MORNING. INTO MONDAY AFTN...WIND FIELD BECOMES GENERALLY LIGHT AND
VARIABLE WHICH OPENS DOOR FOR LK BREEZE SHRA/TSRA OVER MAINLY CNTRL
UPR MICHIGAN /MQT-ESC-P53/. KEPT A SMALL POP IN THERE. WOULD BE VERY
LOW CHANCE IF THERE IS MORE FORMIDABLE CONVECTION AROUND MONDAY
MORNING AS SUBSIDENCE LATER IN THE DAY WOULD LIKELY PUT CAP ON ANY
ADDITIONAL SHRA/TSRA. HIGHS ON MONDAY COULD SURGE INTO THE LOW-MID
80S OVER SCNTRL BUT SHOULD STAY IN THE MID-UPR 70S ELSEWHERE. WILL
BECOME INCREASINGLY LESS HUMID LATER MONDAY AFTN OVER WESTERN UPR
MICHIGAN. DEVELOPING ONSHORE FLOW IN AFTN MAY RESULT IN SOME FOG IN
IMMEDIATE LK SUPERIOR SHORELINE AREAS EAST OF MQT.
GOING TO GO FOR PERIOD OF QUIET WEATHER MONDAY NIGHT AND FOR MOST OF
TUESDAY AS WELL. SFC-H85 FRONTAL BOUNDARIES AND ASSOCIATED SHRA/TSRA
LOOK TO SETTLE WELL TO SOUTH OF CWA MONDAY EVENING. OTHER THAN
WEAKER SHORTWAVES TRAVELLING THROUGH GENERAL FLAT RIDGING
ALOFT...THERE REALLY IS NOT A STRONG ENOUGH FEATURE TO BRING THE
FRONTS BACK TO THE NORTH. EXPECT SHRA/TSRA TO STAY OVER SOUTHERN
HALF OF MN AND WI MONDAY NIGHT INTO TUESDAY MORNING. PERHAPS ISOLD
SHRA/TSRA MAKE INTO TO THE WI BORDER LATE TUESDAY AFTN/EVENING AS
SFC-H85 FRONTS TRY TO LIFT BACK TO THE NORTH OUT AHEAD OF LARGER
SCALE TROUGHING MOVING ACROSS SCNTRL CANADA. ON THE OTHER
HAND...MAYBE THIS NEXT ROUND OF SHRA/TSRA REMAINS MAINLY TO THE
SOUTH OF UPR MICHIGAN SINCE SFC FRONT/MORE ABUNDANT INSTABILITY
STAYS TO THE SOUTH. TOUGH TO SAY REALLY AS AT THE SAME TIME...H7
TEMPS PROGGED TO SURGE UPWARD AS CAPPING BUILDS JUST TO THE SOUTH
OF UPR MICHIGAN. KEPT POPS CHANCE ALL AREAS...WITH HIGHEST CHANCES
CONFINED TO SOUTH CENTRAL UPR MICHIGAN. KEPT SIMILAR IDEA GOING
WEDNESDAY AS WELL WITH HIGHEST POPS ALONG WI BORDER INTO SCNTRL UPR
MICHIGAN. WENT WITH MORE BROADBRUSHED APPROACH TO POPS WEDNESDAY
NIGHT INTO THURSDAY AS COLD FRONT PRESSES IN FROM MANITOBA/ONTARIO
AHEAD OF DEEPER UPR LEVEL TROUGH THAT DIGS INTO UPR LAKES REGION
THURSDAY NIGHT INTO FRIDAY.
WARM AND HUMID AIRMASS EXITS TO THE EAST BY THURSDAY NIGHT. HIGH
TEMPS FOR FRIDAY AND NEXT SATURDAY SHOULD END UP BLO NORMAL ALL
AREAS. COULD SEE CHANCES OF MAINLY RAIN SHOWERS /NO TSRA/ AS UPR
TROUGH SETTLES ACROSS THE AREA. GUSTY NORTHWEST WINDS LIKELY AS WELL
ALONG LK SUPERIOR ON FRIDAY AS THE COOLER AIR ARRIVES. PATTERN WILL
FAVOR POTENTIAL FOR INCREASED SWIM RISK ON THE LAKE SUPERIOR BEACHES
FOR FRIDAY. ARRIVAL OF THE COOLER AND DRIER AIRMASS SHOULD FINALLY
SCOUR OUT THE FOG ON LK SUPERIOR.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON)
ISSUED AT 155 PM EDT SAT JUN 22 2013
WITH ABUNDANT LOW-LEVEL MOISTURE LINGERING OVER THE REGION NORTH OF
A WARM FRONT...EXPECT LOWER CIGS TO PEVAIL THIS AFTERNOON. UPSLOPE ENE
FLOW INTO SAW WILL KEEP LIFR/IFR CONDITIONS IN PLACE TIL LATE THIS
AFTERNOON WHEN DAYTIME HEATING/MIXING HELPS BRING IMPROVEMENT INTO
THE MVFR RANGE. LOSS OF DAYTIME HEATING AND CONTINUED COOL EASTERLY
UPSLOPE FLOW SHOULD BRING A RETURN OF FOG/LIFR CONDITIONS TO KCMX IN
THE EVENING. DOWNSLOPE SE FLOW SHOULD MAY KEEP MVFR CONDITIONS AT
KIWD INTO THE EVENING. AS FOR PCPN...SHRA/TSRA POTENTIAL IS VERY
UNCERTAIN AND IS EXPECTED TO BE MORE SCT OR ISOLD IF ANY DEVELOPS
LATE THIS AFTERNOON OR EVENING. CONFIDENCE WAS NOT HIGH ENOUGH TO
INCLUDE MENTION IN THE TAF AT THIS ISSUANCE.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 423 PM EDT SAT JUN 22 2013
WINDS SHOULD REMAIN 25 KTS OR LESS THROUGH THE UPCOMING WEEK. MAIN
HAZARDS FOR MOST OF THE TIME WILL CONTINUE TO BE THUNDERSTORMS AND
FOG. DENSE FOG ADVISORIES HAVE BEEN EXTENDED INTO SUNDAY.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
DENSE FOG ADVISORY UNTIL 10 AM EDT /9 AM CDT/ SUNDAY FOR LSZ162-
240>250-263>267.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...JLB
LONG TERM...JLA
AVIATION...JLB
MARINE...JLA
AREA FORECAST DISCUSSION
NWS JACKSON MS
1217 PM CDT SAT JUN 22 2013
.UPDATE...
WILL UPDATE TO INCREASE POPS A BIT FOR THE AFTERNOON...BUT STILL
EXPECT COVERAGE TO REMAIN FAIRLY ISOLATED. A FEW SHOWERS/THUNDERSHOWERS
HAVE DEVELOPED ALONG/WEST OF THE I-55 CORRIDOR IN REGION OF SUBTLE
LOW LEVEL MOISTURE CONVERGENCE INDUCED BY WEAK UPPER LEVEL DIVERGENCE
ALONG THE MS RIVER. MORNING RUNS OF THE HRRR HAD SEEMED A LITTLE
OVERDONE BUT LOOK PRETTY GOOD RIGHT NOW. /EC/
&&
.PREV DISCUSSION... /ISSUED 1059 AM CDT SAT JUN 22 2013/
UPDATE...
THE FORECAST IS ON TRACK AND ONLY MINOR ADJUSTMENTS WERE MADE TO
TEMPERATURES AND AFTERNOON WEATHER. DID NOT ADJUST LOW POPS...BUT
VARIOUS HIGH-RES GUIDANCE SUGGEST ISOLATED SHOWERS/THUNDERSHOWERS ARE
A GOOD POSSIBILITY OVER WESTERN/SOUTHERN PORTIONS OF THE FORECAST
AREA AND HAVE ADDED EXPLICIT MENTION. /EC/
&&
.AVIATION...
VFR CONDS TO PERSIST THRU THE REMAINDER OF THE DAY. ISOLD SHRA MAY
DEVELOP ACROSS SRN MS THRU THE AFTN BEFORE QUIET CONDS RETURN THIS
EVE. MVFR/IFR CIG AND VSBY MAY DEVELOP AT HBG/PIB TOMORROW MORNING
10-14Z. SFC WINDS WL REMAIN LGT AND ELY/SELY OVR THE NEXT 24 HRS.
/BK/
PREV DISCUSSION... /ISSUED 334 AM CDT SAT JUN 22 2013/
SHORT TERM...TODAY THROUGH SUNDAY NIGHT...WEAK E/SELY ANTICYCLONIC
FLOW AT LOWER LEVELS ALONG WITH BACKING FLOW ALOFT WILL KEEP
CONVECTION GENERALLY QUIET TODAY. ONE OR TWO VERY ISOLATED CELLS
MAY POP UP DURING THE LATE AFTERNOON AND EARLY EVENING BUT
CONDITIONS WILL GENERALLY REMAIN DRY ACROSS THE REGION. RAIN CHANCES
WILL INCREASE SOMEWHAT FOR SUNDAY AFTERNOON AND EVENING...MAINLY IN
THE SOUTH. WEAK LOW LEVEL CONVERGENCE AND THE DEVELOPMENT OF FLAT
UPPER TROUGHING SUNDAY WILL PRODUCE ISOLATED TO SCATTERED SHOWERS
AND THUNDERSTORMS GENERALLY I-20 SWD IN THE AFTERNOON AND EVENING
SUNDAY.
OTHER THAN A FEW SMALL TWEAKS MAV MOS GUIDANCE WAS FOLLOWED...
TEMPERATURES PRIMARILY CONTINUING CLOSE TO SEASONAL NORMS.
LONG TERM...MONDAY INTO NEXT WEEKEND...THIS PORTION OF THE FORECAST
LOOKING RATHER TYPICAL...ALTHOUGH PERHAPS A BIT ON THE DRYISH
SIDE...THROUGH AT LEAST NEXT THURSDAY. THROUGH THE WEEK THE CENTER
OF SUPPRESSIVE SUBTROPICAL RIDGING ALOFT WILL SHIFT FARTHER AND
FARTHER WEST OF OUR REGION ALTHOUGH TRUE TROUGHING SHOULD NOT DIG
DOWN THIS WAY UNTIL AROUND FRIDAY. FLOW AT THE SURFACE WILL
GENERALLY BE WEAK AND SOUTHERLY...BUT EXHIBITING SOME ANTICYCLONIC
TENDENCIES DUE TO AT LEAST WEAK SUBSIDENCE IN THE VICINITY FOR MUCH
OF THE WEEK. BECAUSE OF THIS LATTER FACT...AND THE IDEA THAT SURFACE
COMBINATIONS OF HEAT AND HUMIDITY WILL NOT BE OVERLY HIGH...EXPECT
AFTERNOON CONVECTION TO BE GENERALLY ISOLATED AT BEST THROUGH THE
WORK WEEK. EXCEPTIONS TO THIS COULD COME IN SOUTHERN ZONES BY
THURSDAY AND FRIDAY WHEN ACTIVE SEABREEZE-RELATED BOUNDARIES HAVE A
BETTER CHANCE OF GETTING SUFFICIENTLY NORTH FROM THE COAST.
BY FRIDAY AND DEFINITELY INTO NEXT WEEKEND NUMERICAL MODEL CONSENSUS
IS FAIRLY GOOD THAT A SOMEWHAT SIGNIFICANT SUMMER UPPER LEVEL TROUGH
WILL DIG DOWN INTO THE EASTERN HALF OF THE CONUS. THIS SHOULD DRIVE
A COLD FRONT SOUTH INTO OUR REGION BY SATURDAY...WITH THIS BOUNDARY
REACTING WITH MOISTURE AND INSTABILITY TO INCREASE THUNDERSTORM
PRODUCTION A GOOD DEAL. AT THIS POINT IT IS HARD TO SAY WHETHER THIS
TROUGH WILL BE A BIG ENOUGH DEAL TO TRULY PUSH THE FRONT SOUTH OF
OUR REGION...WHICH IS SOMETHING HARD TO DO AT THE START OF JULY.
AS FOR TEMPERATURES...GFS-BASED MEX GUIDANCE LOOKED GOOD ADVERTISING
TEMPS PERHAPS SLIGHTLY ABOVE AVERAGE FOR HIGHS BUT NEAR AVERAGE FOR
LOWS. I MADE ONLY A FEW SLIGHT TWEAKS THROUGH THE PERIOD BASED ON
TRENDS THUS FAR THIS SUMMER. OF COURSE SOME DEGREE OF COOL DOWN
ANTICIPATED BY NEXT WEEKEND WITH THE FRONT COMING IN...BUT UNTIL
THEN HEAT SHOULD NOT BE OPPRESSIVE ENOUGH TO WARRANT HEAT
ADVISORIES.
FINALLY...MONDAY THROUGH AT LEAST THURSDAY THERE ARE NO SIGNALS FOR
MUCH ROBUST TSTORM ACTIVITY. STRONGER STORMS POSSIBLE WITH THE FRONT
AT THE END OF THE WEEK BUT IT IS STILL WAY TOO EARLY TO ADVERTISE
THAT IN THE HWO. /BB/
&&
.JAN WATCHES/WARNINGS/ADVISORIES...
MS...NONE.
LA...NONE.
AR...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS GREAT FALLS MT
250 PM MDT Sat Jun 22 2013
.DISCUSSION...
Tonight through Monday...Upper trof presently over the state.
Associated cold pool aloft contributing to the instability and
the resulting scattered thunderstorms. Thunderstorm activity has
decreased the past couple of hours but HRRR analysis and the
latest RUC indicate isolated storms remain a possibility during
the evening hours. The upper trof moves east and away from the
area Sunday. Rising heights will bring drier conditions with the
exception of the area along the international boundary. Cyclonic
flow from the departing upper low over central Saskatchewan will
lead to an area of convergence along the border and the
possibility of isolated convection during the afternoon. By
Monday, an increasing southwest flow aloft will bring another round
of moisture and instability to the area with scattered
thunderstorms developing again during the afternoon. Temperatures
will climb to near or slightly above seasonal averages to start
the week. Emanuel
Monday night through Saturday...Expect two different weather
patterns during the period. Early in the week models indicate a
moist southwest flow aloft. A weather disturbance aloft is
expected to move northeast through the area Monday night and
Tuesday with the GFS model faster with this feature than the ECMWF
and GEM models. Models differ with details of their precipitation
forecasts so have not fiddled much with the inherited forecast of
a chance of showers/thunderstorms. At this time it does not look
like thunderstorms will be severe. Then later in the week models
are on the same page in developing a strong upper ridge over the
western U.S. with forecast temperatures rising to well above
normal. Will continue to forecast high temperatures above most
forecast guidance from the models. Thus expect highs in the upper
80s to lower 90s for the lower elevations Friday and Saturday. The
intensifying upper ridge should also result in dry weather
Wednesday night through Friday. Friday night through Saturday
could see an increase in moisture mainly over the northern zones.
Will follow the lead of the Glasgow weather office and mention a
slight chance of showers/thunderstorms in the north. Blank
&&
.AVIATION...
Updated 1720Z.
An unstable airmass remains over the area today. The greatest
instability will be over southwest and central Montana, along and
south of a KHLN to KLWT line. Some of the heavier showers and storms
will produce gusty winds...small hail...and could result in brief
MVFR conditions. Expect most of the showers and storms to diminish
this evening with VFR conditions prevailing through noon Sunday.
Winds will remain light today except near showers and storms.
Langlieb
&&
.PRELIMINARY POINT TEMPS/POPS...
GTF 45 75 51 78 / 20 10 10 30
CTB 44 73 49 73 / 10 20 20 40
HLN 45 77 52 78 / 20 10 10 30
BZN 40 76 46 80 / 20 10 10 30
WEY 31 68 36 70 / 20 10 10 30
DLN 39 74 47 74 / 20 10 10 30
HVR 48 77 53 81 / 20 20 10 30
LWT 43 72 48 78 / 40 10 10 30
&&
.TFX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...
LONG TERM...
AVIATION...
weather.gov/greatfalls
AREA FORECAST DISCUSSION
NWS GREAT FALLS MT
1120 AM MDT Sat Jun 22 2013
UPDATED AVIATION SECTION
.DISCUSSION...
Update forthcoming. Upper trof over the area today will bring
scattered showers and thunderstorms. Radar continues to indicate a
line of showers along the Belts that is very slowly moving to the
north. HRRR analysis indicates this line will become an area of
scattered showers later this afternoon. Have made minor adjustments
to the pop grids. Temperatures look good. Emanuel
&&
.AVIATION...
Updated 1720Z.
An unstable airmass remains over the area today. The greatest
instability will be over southwest and central Montana, along and
south of a KHLN to KLWT line. Some of the heavier showers and storms
will produce gusty winds...small hail...and could result in brief
MVFR conditions. Expect most of the showers and storms to diminish
this evening with VFR conditions prevailing through noon Sunday.
Winds will remain light today except near showers and storms.
Langlieb
&&
.PREV DISCUSSION...Issued 416 AM MDT Sat Jun 22 2013
Today through Monday...Another cool and unsettled weather day is
expected across much of Southwest and Central MT today. With the
main upper level low expected to move eastward across southern
Idaho today...combined with some fairly cold air aloft...another
day of small hail will be possible across portions of Central MT
from any of the stronger storms. Severe storms are not
expected...as the instability is not expected to be very high.
Additionally...light snow will fall this morning across the higher
elevations of Southwest MT...mainly above 7000 feet. New snow
accumulations should generally be less than inch. Afternoon
temperatures will remain a bit below normal...with highs mostly in
the 60s at lower elevations. For Sunday...expect the area to
mainly be in-between storm system...with the flow aloft becoming a
bit more southwesterly. This will result in warmer air returning
to the region...and the best chance for any precipitation to occur
will be over the front range of the Rockies and near the
US/Canadian border. For Monday...the next upper level trof begins
to approach the region. However...forecast models differ on how
far east the trof will be by late Monday afternoon.
Therefore...have continued the slight chance for thunderstorms
east of Great Falls...with higher chances west of Great Falls.
Afternoon temperatures will be on the warm side...especially east
of Great Falls. Brusda
Monday night through Saturday...Expect two different weather
patterns during the period. Early in the week models indicate a
moist southwest flow aloft. A weather disturbance aloft is expected
to move northeast through the area Monday night and Tuesday with the
GFS model faster with this feature than the ECMWF and GEM models.
Models differ with details of their precipitation forecasts so have
not fiddled much with the inherited forecast of a chance of
showers/thunderstorms. At this time it does not look like
thunderstorms will be severe. Then later in the week models are on
the same page in developing a strong upper ridge over the western
U.S. with forecast temperatures rising to well above normal. Will
continue to forecast high temperatures above most forecast guidance
from the models. Thus expect highs in the upper 80s to lower 90s for
the lower elevations Friday and Saturday. The intensifying
upper ridge should also result in dry weather Wednesday night
through Friday. Friday night through Saturday could see an increase
in moisture mainly over the northern zones. Will follow the lead of
the Glasgow weather office and mention a slight chance of
showers/thunderstorms in the north. Blank
&&
.PRELIMINARY POINT TEMPS/POPS...
GTF 68 44 78 50 / 50 20 10 10
CTB 67 44 75 48 / 20 10 20 10
HLN 67 45 79 51 / 60 20 10 10
BZN 67 40 80 45 / 80 20 10 10
WEY 59 31 67 35 / 70 20 10 10
DLN 65 39 75 46 / 40 20 10 10
HVR 72 47 79 52 / 20 20 20 10
LWT 62 43 74 47 / 80 30 10 10
&&
.TFX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
weather.gov/greatfalls
AREA FORECAST DISCUSSION
NWS GREAT FALLS MT
10 AM MDT Sat Jun 22 2013
.DISCUSSION...
Update forthcoming. Upper trof over the area today will bring
scattered showers and thunderstorms. Radar continues to indicate a
line of showers along the Belts that is very slowly moving to the
north. HRRR analysis indicates this line will become an area of
scattered showers later this afternoon. Have made minor adjustments
to the pop grids. Temperatures look good. Emanuel
&&
.AVIATION...
Updated 1130Z.
An upper trough will move over the area today and bring occasional
showers and a few thunderstorms to central and southwest Montana.
Towards the Canadian border expect just a few showers and isolated
thunderstorms. With the showers and thunderstorms expect local MVFR
ceilings and possibly visibilities. Also early this morning there
will be local IFR ceilings/visibilities in fog over central Montana.
Do not expect any taf sites to be affected by fog except possibly
KLWT. Other than local lower conditions with fog and thunderstorms
expect VFR conditions today. With the thunderstorms there will also
be the threat of small hail and gusty winds to possibly as high as
35 knots. Other than gusty winds with some of the thunderstorms
winds should be generally light through the period and confidence in
forecast winds is low to moderate. Showers and thunderstorms will
diminish this evening. Blank
&&
.PREV DISCUSSION...Issued 416 AM MDT Sat Jun 22 2013
Today through Monday...Another cool and unsettled weather day is
expected across much of Southwest and Central MT today. With the
main upper level low expected to move eastward across southern
Idaho today...combined with some fairly cold air aloft...another
day of small hail will be possible across portions of Central MT
from any of the stronger storms. Severe storms are not
expected...as the instability is not expected to be very high.
Additionally...light snow will fall this morning across the higher
elevations of Southwest MT...mainly above 7000 feet. New snow
accumulations should generally be less than inch. Afternoon
temperatures will remain a bit below normal...with highs mostly in
the 60s at lower elevations. For Sunday...expect the area to
mainly be in-between storm system...with the flow aloft becoming a
bit more southwesterly. This will result in warmer air returning
to the region...and the best chance for any precipitation to occur
will be over the front range of the Rockies and near the
US/Canadian border. For Monday...the next upper level trof begins
to approach the region. However...forecast models differ on how
far east the trof will be by late Monday afternoon.
Therefore...have continued the slight chance for thunderstorms
east of Great Falls...with higher chances west of Great Falls.
Afternoon temperatures will be on the warm side...especially east
of Great Falls. Brusda
Monday night through Saturday...Expect two different weather
patterns during the period. Early in the week models indicate a
moist southwest flow aloft. A weather disturbance aloft is expected
to move northeast through the area Monday night and Tuesday with the
GFS model faster with this feature than the ECMWF and GEM models.
Models differ with details of their precipitation forecasts so have
not fiddled much with the inherited forecast of a chance of
showers/thunderstorms. At this time it does not look like
thunderstorms will be severe. Then later in the week models are on
the same page in developing a strong upper ridge over the western
U.S. with forecast temperatures rising to well above normal. Will
continue to forecast high temperatures above most forecast guidance
from the models. Thus expect highs in the upper 80s to lower 90s for
the lower elevations Friday and Saturday. The intensifying
upper ridge should also result in dry weather Wednesday night
through Friday. Friday night through Saturday could see an increase
in moisture mainly over the northern zones. Will follow the lead of
the Glasgow weather office and mention a slight chance of
showers/thunderstorms in the north. Blank
&&
.PRELIMINARY POINT TEMPS/POPS...
GTF 68 44 78 50 / 50 20 10 10
CTB 67 44 75 48 / 20 10 20 10
HLN 67 45 79 51 / 60 20 10 10
BZN 67 40 80 45 / 80 20 10 10
WEY 59 31 67 35 / 70 20 10 10
DLN 65 39 75 46 / 40 20 10 10
HVR 72 47 79 52 / 20 20 20 10
LWT 62 43 74 47 / 80 30 10 10
&&
.TFX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
weather.gov/greatfalls
AREA FORECAST DISCUSSION
NWS OMAHA/VALLEY NE
343 PM CDT SAT JUN 22 2013
.DISCUSSION...
THUNDERSTORM CHANCES THROUGH SUNDAY OR MONDAY...THEN WARMING NEXT
WEEK...REMAIN THE PRIMARY FORECAST CONCERNS.
THUNDERSTORMS THAT DEVELOPED IN WESTERN NEBRASKA FRIDAY
AFTERNOON/EVENING HELD TOGETHER OVERNIGHT FUELED BY THETA-E
ADVECTION ON NOSE OF LOW LEVEL JET. STORMS SWEPT ACROSS MUCH OF
EASTERN NEBRASKA AND WEST CENTRAL IOWA DURING THE MORNING BUT HAD
DECREASED MARKEDLY BY LATE MORNING. ATTENDANT CLOUD SHIELD HELD
TEMPERATURES DOWN MUCH OF THE MORNING...BUT RETURNING SOUTH WINDS
AND MORE SUNSHINE THIS AFTERNOON PUSHED TEMPERATURES TOWARD OR ABOVE
90 IN ALL BUT NORTHEAST NEBRASKA WHERE TEMPS LAGGED IN THE UPPER
70S OR LOWER 80S. DEW POINTS WERE BETWEEN 65 AND 70.
LOOKS LIKE MORNING CONVECTION HAS STABILIZED ATMOSPHERE FOR LATE
AFTERNOON ACTIVITY FOR THE MOST PART. RAP MESOANALYSIS SHOWS
MUCAPE VALUES WELL OVER 2000 J/KG IN THE SOUTHERN HALF OF THE
CWA...BUT LOW LEVEL CONVERGENCE IS NEGLIGIBLE. MEANWHILE IN THE
NORTHEAST WHERE SOME SURFACE CONVERGENCE IS NOTED...COOLER
SURFACE TEMPS BEHIND EXITING CONVECTION HAS KEPT MUCAPE LOW.
EXPECT THAT TO ERODE LATER THIS EVENING AS A MID LEVEL IMPULSE
MOVING OUT OF EASTERN COLORADO/WYOMING COOLS MID LEVEL ATMOSPHERE
AS SURFACE TEMPERATURES REBOUND SOMEWHAT. BETTER CHANCES FOR
EVENING CONVECTION LIES TO OUR WEST WHERE CAPES ARE INCREASING AND
CAP DIMINISHING...AND LATEST MESO DISCUSSIONS FROM SPC SUGGEST
WATCH IS LIKELY FOR PARTS OF WESTERN AND CENTRAL NEBRASKA. THESE
STORMS WILL MOVE NORTHEAST TOWARD NORTHEAST NEBRASKA...THEN
PROPAGATE SOUTHEAST WITH TIME AS LOW LEVEL JET KICKS IN
OVERNIGHT...PROBABLY REACHING THE I-80 CORRIDOR LATE TONIGHT.
SEVERE THREAT SHOULD WANE AFTER MIDNIGHT...BUT ANY OF THE STRONGER
STORMS COULD PRODUCE WIND AND POSSIBLY HAIL AS FREEZING LEVELS
HAVE COME DOWN SOME FROM YESTERDAY.
WOULD EXPECT A DECREASING TREND AGAIN SUNDAY MORNING...THEN
REDEVELOPMENT IN THE AFTERNOON ALONG COLD FRONT THAT WILL BE
DRIFTING INTO THE NORTHWEST CWA IN THE MORNING. WHERE THAT FRONT
WILL SET UP WILL BE AFFECTED BY MORNING CONVECTION...BUT MOST
LIKELY WILL LIE SOMEWHERE CLOSE TO I-80 CORRIDOR IN THE
AFTERNOON. SUNSHINE AND POOLING DEW POINTS ALONG FRONT WILL YIELD
CAPES CLOSE TO 3000 J/KG ALONG WITH 30KT 0-6KM SHEAR. FRONTAL
CONVERGENCE UNDER STEEP LAPSE RATES NEAR 8 C/KM SUGGEST STORMS
WILL FIRE LATE IN THE DAY AS CAP WEAKENS. ALL MODES OF SEVERE ARE
POSSIBLE...AS SHEAR/INSTABILITY AND LOWERING FREEZING LEVELS POINT
TO WIND AND HAIL. AND LOW LEVEL VORTICITY/HELICITY/EHI SUPPORT AN
ISOLATED TORNADO THREAT.
EXPECT STORMS TO CONTINUE THROUGH THE EVENING WITH SEVERE THREAT
GRADUALLY DIMINISHING LATE IN THE EVENING. AGAIN ANOTHER ROUND OF
STORMS FROM THE HIGH PLAINS MAY ROLL ACROSS NORTHERN CWA AFTER
MIDNIGHT.
AFTER MORNING CONVECTION MONDAY...MUCH OF NEXT WEEK LOOKS DRY AS
HEIGHTS BUILD FROM THE SOUTHWEST AND SOUTH INTO THE CENTRAL PLAINS.
HOWEVER ANOTHER ROUND OF STORMS MONDAY AFTERNOON...BUT WOULD FAVOR
AREAS NORTH OF NEBRASKA. BY LATE IN THE WEEK...A MID LEVEL TROUGH
DEEPENING NEAR AND NORTH OF THE GREAT LAKES COULD DRIVE A BACKDOOR
COLD FRONT INTO OUR AREA. MODELS REMAIN BEARISH WITH PRECIP CHANCES
THEN...BUT SLIGHTLY COOLER AIR WILL FOLLOW. LOOKS LIKE HIGHS IN THE
90S WILL BE COMMON THROUGH MUCH OF THE WEEK...WITH 80S FRIDAY AND
SATURDAY.
DERGAN
&&
.AVIATION...18Z TAFS FOR KOMA...KLNK...AND KOFK.
SOUTHEAST WINDS WILL REMAIN STRONG 14 TO 22KTS SUSTAINED WITH
GUSTS 20 TO 30KTS...DECREASING TONIGHT...HOWEVER LLWS DEVELOPS BY
06Z. VFR CONDITIONS FOR NOW WITH BREAK IN THE PRECIPITATION.
THUNDERSTORMS MAY DEVELOP IN THE KOFK AREA LATER THIS AFTERNOON OR
EVENING...HOWEVER FOR NOW INCLUDED MVFR VSBYS WITH THE
PRECIPITATION LATER THIS EVENING AND OVERNIGHT AT ALL THREE
SITES.
ZAPOTOCNY
&&
.OAX WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
IA...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
251 PM EDT SAT JUN 22 2013
.SYNOPSIS...
HIGH PRESSURE BUILDING INTO THE NORTHEAST WILL BRING WARM
TEMPERATURES TO THE REGION. INCREASING HUMIDITY LEVELS MAY PROVIDE
THE SPARK FOR A FEW AFTERNOON THUNDERSTORMS THROUGH THE PERIOD. AN
UPPER LEVEL TROUGH WILL SKIRT THROUGH BY MID-WEEK WITH A BETTER
CHANCE FOR SHOWERS AND THUNDERSTORMS.
&&
.NEAR TERM /UNTIL 6 AM SUNDAY MORNING/...
250 PM UPDATE...
SHOWERS HV DVLPD ACRS SRN ONTARIO THIS AFTN IN CONJUNCTION WITH
S/WV. APPEARS AS THO THE BULK OF THESE SHOWERS/TSTMS WL GO ACRS NRN
ZONES GNRLY NORTH OF THE THRUWAY. ANOTHER LINE OF STORMS IS DVLPNG
ACRS WRN OH AND SLOWLY TRYING TO FILL IN IN CONVERGENCE ZONE AND
POOLING DWPTS. THE LATEST HRRR MODEL DATA THIS WL FILL IN ACRS WRN
PA AND THEN BREAK UP AS IT HEADS FURTHER EAST AWAY FM CONVERGENT
AXIS THEREFORE EXPECT CH THUNDER AFT 00Z OVR FAR NRN ZONES AND ISOLD
AT BEST ACRS REMAINDER OF NY CNTYS WITH LOSS OF DAYTIME HTG.
FCST FOR TONIGHT WL BE COMPLICATED BY TWO POTENTIAL ISSUES. ANY MCS
THAT MAY DVLP ACRS THE NRN PLAINS SPREADING HIGH CIRRUS INTO AREA. A
CLOSED H5 LOW WL DRIFT NORTHWARD FM THE SERN U.S. IN AREA OF
STRONGEST HEIGHT FALLS PER 12Z RAOBS. QUESTION WL BE HOW QUICKLY
THESE CLDS WL IMPACT AREA AND THE RESULT ON FOG DVLPMNT.
FOR NOW HV GONE WITH MOCLDY ACRS NRN ZONES DUE TO BEING CLOSER IN
PROXIMITY TO MAIN STORM TRACK AND STATIONARY BNDRY IN WHICH ANY
SUBTLE S/WVS MAY RIDE ALONG. FURTHER TO THE SOUTH, AT LEAST
INITIALLY TONIGHT SKIES WL BE MOCLR AS UL RIDGE BUILDS IN AHD OF H5
LOW EJECTING NORTH. AFT 06Z FCST WL BE TOTALLY DEPENDENT ON HOW FAST
SYSTEM CAN MV NWRD. LATEST CMC CLD FCST INDICATING CLR SKIES ALL THE
WAY THRU 12Z. 12Z NAM AND GFS INDICATE RIDGE FLATTENING SLIGHTLY
TONIGHT AND ALLOWING CLDS TO SPILL DOWN INTO NEPA THEN PUMPING BACK
UP TWD 12Z. FOR NOW, HV CALLED IT PCLDY AFT 06Z THO THIS MAY NEED
TO BE TWEAKED BY LATER SHIFTS.
AS FOR FOG POTENTIAL BL IS CERTAINLY MOIST ENUF AND WITH RVR VLYS
DROPPING DOWN THIS MRNG, SEE A REPEAT OF THIS, IF CLRNG CAN DEVELOP
ACRS SRN TIER AND POINTS SOUTH. THEREFORE WL KEEP PATCHY FOG IN
GRIDS STARTING AT 09Z AND THEN SCATTERING OUT BY 13Z. EXPECT OVRNGT
MINS TO RMN IN THE 60S AREAWIDE DUE TO CLD CVR AND H8 TEMPS INCRSG
DUE TO CONTD WAA.
&&
.SHORT TERM /6 AM SUNDAY MORNING THROUGH TUESDAY/...
250 PM UPDATE...
SHORT TERM WL RMN AS IS WITH A CHC OF DIURNAL CONVECTION EACH AFTN
AND POTENTIAL FOR RVR VLY FOG OVRNGT. HIGHS WL TOP OUT IN THE M/U
80S EACH DAY WITH MINS DIPPING INTO THE 60S.
H5 LOW WL EJECT THRU OH VLY SUNDAY NGT WITH CHC FOR RENEGADE STORMS
AT ANYTIME ACRS THE CWA. THUS, WL KEEP MENTION OF ISOLD POPS IN FOR
MOST OF THE AREA THRU 12Z MONDAY. MAIN TROF WL ZIP THRU AREA ON
MONDAY WITH BETTER CHC FOR CONVECTION DRG THE AFTN. WV AFT WV WL
PERSIST THRU THE END OF THE SHORT TERM WITH CHC POPS EACH DAY.
&&
.LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/...
MOST OPERATIONAL MODELS AND ENSEMBLES SUGGEST THAT THE PATTERN
WILL BECOME INCREASINGLY CYCLONIC ACROSS THE NORTHEASTERN US
DURING THE UPCOMING WEEK. THIS WILL TEND TO INCREASE THE CHANCES
FOR UNSETTLED CONDITIONS...ESPECIALLY HEADING THROUGH THURSDAY AND
FRIDAY WITH THE WPC ANALYSTS INDICATING THE PASSAGE OF WARM AND
COLD FRONTS EACH DAY. WITH ONLY BROAD FORCING NOTED IN THE MODELS...
NOTHING REALLY SUGGESTS THAT WE WILL BE FACING A PROLONGED SOAKING
EVENT...UNTIL POSSIBLY A SHOT WITH THE FRONTS ON FRIDAY...IF IT
OCCURS. WPC GUIDANCE SUGGESTED 60-70 POPS ON THURS-FRI BUT THIS
IS SUMMER TIME AND CONFIDENCE IS USUALLY NOT HIGH ENOUGH TO GO SO
FAR ABOVE CLIMO AT DAYS 6-7 SO HAVE GONE BELOW THE GUIDANCE AND
EVEN A TAD LOWER THAN OUR PREV FORECAST ACROSS THE BOARD GIVEN
SUCH UNCERTAINTY.
HAVE ALSO NUDGED MAX TEMPERATURES UP HIGHER THAN RECOMMENDED
GUIDANCE GIVEN LITTLE BUDGE IN THE ECMWF/GFS THERMAL FIELDS WHICH
SUGGEST ABOVE NORMAL TEMPERATURES BY 1-2 STANDARD DEVIATIONS FOR
MUCH OF THE WEEK UNTIL THE TROF REALLY KICKS IN GOING INTO NEXT WEEKEND.
SHOULD EASILY SEE UPPER 80S-AROUND 90 WEDNESDAY FOLLOWED BY TEMPS
REMAINING IN THE LOW-MID 80S ONLY TEMPERED BY CLOUDS AND SHOWERS.
MUGGY LOW-MID 60S WILL BE COMMON FOR LOWS.
&&
.AVIATION /19Z SATURDAY THROUGH THURSDAY/...
MINOR DISTURBANCE MOVING ACROSS LOWER ONTARIO WILL ENTER N CNTRL
NY EARLY THIS AFTERNOON WITH A PERIOD OF SHRA/TSRA AFFECTING
KSYR-KRME. DIFFICULT TO ASSESS SOUTHERN EXTENT OF CONVECTIVE
DEVELOPMENT GIVEN BALANCE BETWEEN DESTABILIZATION AND MID-LEVEL
THERMAL CAPPING. FOR NOW...HAVE NOT INCLUDED ANY TSRA SOUTH OF
KSYR-KRME ALTHOUGH SOME MODEL FORECASTS SUGGEST THAT KITH-KBGM
AREAS WILL NEED TO BE MONITORED FOR CB DEVELOPMENT. BEYOND 00Z
TONIGHT...THE CONFIDENCE FOR CONVECTIVE DEVELOPMENT WANES PRETTY
QUICKLY AND HAVE NOT INCLUDED IN THIS UPDATE...ALTHOUGH MODELS
HAVE POTENTIAL ACTIVITY THROUGH 06Z...BUT WILL PLAY TYPICAL
DIURNAL TRENDS ATTM. THE MORE TROUBLESOME CONSIDERATIONS ARE FOR IFR
AND ALTERNATE VSBY RESTRICTIONS DUE TO FOG AND HAZE AS LOW LEVEL
MOISTURE WILL BE INCREASING WITH TIME. I SEE ENOUGH EVIDENCE AT
THIS TIME TO INCLUDE SOME OVERNIGHT MVFR EXTENDING ACROSS MOST
TERMINALS WITH IFR LIKELY DEVELOPING AT KELM. LOW LEVEL STRATOCU
CIGS ARE ALSO IN THE REALM OF POSSIBILITY AND HAVE TAGGED A SCT
010-020 FOOT LAYER ONTO THE VSBY RESTRICTIONS AT SVRL LOCATIONS TO
AT LEAST HINT AT THAT POTENTIAL.
WINDS GENERALLY 5-10 KTS FROM THE SOUTHWEST THIS AFTERNOON AND
SUNDAY WITH LIGHT LOCAL DRAINAGE FLOW TONIGHT.
OUTLOOK...SUN THRU WED...VFR MOST OF THE TIME. MVFR VSBY AND CIG
RESTRICTIONS POSSIBLE WITH PASSING SHRA OR TSRA.
&&
.BGM WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NY...NONE.
&&
$$
SYNOPSIS...PVN
NEAR TERM...PVN
SHORT TERM...PVN
LONG TERM...JAB
AVIATION...JAB
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
358 PM CDT SAT JUN 22 2013
.SHORT TERM...(THIS EVENING THROUGH SUNDAY)
ISSUED AT 253 PM CDT SAT JUN 22 2013
AT 3 PM...A WARM FRONT WAS LOCATED NEAR THE INTERSTATE 94 CORRIDOR
AND AN OUTFLOW BOUNDARY OVER NORTHERN IOWA. AS THE TEMPERATURES
RISE ABOVE THE CONVECTIVE TEMPERATURES /LOWER 80S/ LATE THIS
AFTERNOON...EXPECT SCATTERED SHOWERS AND THUNDERSTORMS TO DEVELOP
ALONG AND SOUTH OF THE INTERSTATE 94 CORRIDOR. IN ADDITION...
EXPECT THE SYSTEM MOVING OUT OF NORTHWEST IOWA TO GRADUALLY
UPSCALE AS IT MOVES INTO BETTER CAPES AND MOISTURE TRANSPORT. WITH
0-3 KM SHEAR GREATER THAN 40 KNOTS...THINKING THAT THE STORMS
BECOME MORE COLD POOL DOMINATED THAT THERE WILL ONCE AGAIN BE THE
POTENTIAL FOR SOME BOW ECHOS TO DEVELOP LATE THIS AFTERNOON AND
EVENING. IN ADDITION...WITH 1000 TO 1200 J/KG DCAPES THERE WILL
BE THE POTENTIAL FOR DAMAGING WET MICROBURSTS. WITH PRECIPITABLE
WATER VALUES RUNNING BETWEEN 1.8 AND 2.0 INCHES AND WARM CLOUDS
DEPTHS BETWEEN 4 AND 4.5 KM...EXPECT THE THUNDERSTORMS TO BE VERY
EFFECTIVE RAIN PRODUCERS. HOWEVER IT LOOKS LIKE THEY WILL BE
PROGRESSIVELY MOVING WHICH WILL LIMIT THE THREAT FOR WIDESPREAD FLASH
FLOODING. HOWEVER WITH THIS SAID...WILL STILL HAVE TO WATCH
URBANIZED AREAS WHERE JUST AN INCH OF RAIN AN HOUR CAN RESULT IN
SOME LOCALIZED FLASH FLOODING.
FOR OVERNIGHT...THE 23.12Z DETERMINISTIC MODELS CONTINUE TO SHOW
THAT MUCH OF THE PRECIPITATION FOR THIS TIME PERIOD WILL BE MAINLY
NORTH OF THE INTERSTATE 90 CORRIDOR. THEY HAVE SHOWED THIS FOR THE
PAST 6 MODEL CYCLES. THIS IS IN RESPONSE TO THE TROUGH CURRENTLY
OVER NEBRASKA MOVING NORTHEAST AWAY FROM THE FORECAST AREA. AS
THIS OCCURS...THE NOSE OF THE 850 MB MOISTURE TRANSPORT WILL PUSH
NORTH INTO NORTHERN WISCONSIN. IN THE WAKE OF THIS TROUGH...THE
PRECIPITABLE WATER VALUES DROP TO 1.2 TO 1.4 INCHES...AND THE WARM
CLOUD LAYER DEPTHS FALL INTO THE 3.5 TO 4 KM RANGE. THIS IS IDEA
THAT THE PRECIPITATION COULD BEGIN WANING OVERNIGHT IS SUPPORTED
BY THE LAST 2 RUNS OF THE HRRR WHICH SHOWS A BAND OF SHOWERS
AND THUNDERSTORMS PROGRESSIVELY MOVING NORTHEAST THROUGH CLARK AND
TAYLOR COUNTIES IN NORTH CENTRAL WISCONSIN BETWEEN 23.07Z AND 23.09Z.
FOR SUNDAY AFTERNOON...EXPECT THE UPPER LEVEL TROUGH WHICH HAS
BEEN POSITIONED TO OUR WEST OVER THE LAST SEVERAL DAYS TO MOVE
INTO THE WESTERN PORTIONS OF THE FORECAST AREA. WHILE THE 850 MB
MOISTURE TRANSPORT IS NOT THAT IMPRESSIVE. PRECIPITABLE WATER
VALUES DO CLIMB TO AROUND 1.8 INCHES...WARM CLOUD LAYER DEPTHS
CLIMB ABOVE 4 KM...AND CORFIDI VECTORS SUGGEST TRAINING ALONG AND
AHEAD OF THE COLD FRONT. AS A RESULT...WILL HAVE TO WATCH FOR THE
POTENTIAL FOR SOME FLOODING. CERTAINTY ON THE SPEED AND LOCATION
OF THIS FRONT WAS NOT HIGH ENOUGH TO GO WITH A FLASH FLOOD WATCH
AT THIS TIME.
.LONG TERM...(SUNDAY NIGHT THROUGH SATURDAY)
ISSUED AT 253 PM CDT SAT JUN 22 2013
ON SUNDAY NIGHT AND MONDAY...THE MODELS CONTINUE TO SHOW THAT A SHORT
WAVE TROUGH WILL MOVE ACROSS WESTERN AND NORTHERN MINNESOTA. AS
THIS OCCURS...EXPECT A COLD FRONT TO MOVE THROUGH THE REGION. THIS
FRONT WILL BE THE FOCUS FOR ADDITIONAL SHOWER AND THUNDERSTORM
ACTIVITY. IT MAY MOVE FAR ENOUGH EAST TO ALLOW SOME DRYING ON
MONDAY AFTERNOON.
FROM MONDAY NIGHT THROUGH WEDNESDAY...THE MODELS CONTINUE TO SHOW
THAT A STATIONARY FRONT WILL LINGER ACROSS THE AREA. WHILE THE
MODELS HAVE CONSISTENTLY SHOWED THIS...THEY CONTINUE TO STRUGGLE
ON THE LOCATION AND TIMING OF THUNDERSTORM COMPLEXES WHICH MOVE
THROUGH THE REGION...SO JUST WENT WITH THE ALL BLEND TEMPERATURES
AND PRECIPITATION CHANCES.
FOR THE REMAINDER OF THIS TIME PERIOD...IT CONTINUES TO LOOK LIKE
THE UPPER LEVEL RIDGE WILL RETROGRADE WEST INTO THE WESTERN UNITED
STATES. THIS WOULD PLACE THE AREA UNDER NORTHWEST FLOW ALOFT. AS
A RESULT...EXPECT NEAR TO SLIGHTLY BELOW-NORMAL TEMPERATURES.
PRECIPITATION CHANCES ARE NOT CLEAR AS THERE WILL THE POTENTIAL
FOR SHORT WAVE TROUGHS TO MOVE SOUTHEAST THROUGH THE AREA.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON)
ISSUED AT 1248 PM CDT SAT JUN 22 2013
EXPECTING SCATTERED THUNDERSTORMS TO FIRE THIS AFTERNOON ALONG A
WARM FRONT SITUATED ALONG THE IA/MN BORDER. PLAN ON THE BULK OF THIS
THUNDERSTORM ACTIVITY TO EXTEND FROM KFSD THROUGH SOUTH-CENTRAL
MN...WITH EASTERN FRINGES OF THIS CONVECTION REACHING TOWARD THE
MISSISSIPPI RIVER INCLUDING KRST/KLSE TAF SITES. THE WARM FRONT IS
EXPECTED TO PUSH NORTH OF THE AREA AFTER MIDNIGHT...TAKING THE
THUNDERSTORM ACTIVITY WITH IT. BOTTOM LINE...INCLUDED VCTS BKN030-035CB
IN THE KRST/KLSE TAFS FROM 21Z THROUGH 06Z. OTHER THAN SOME 6SM
BR IN THE 08-13Z TIME FRAME...EXPECTING VFR CONDITIONS THEN TO
PREVAIL THROUGH 18Z SUNDAY. SHRA/TS LOOKING LIKELY AGAIN SUNDAY
AFTERNOON/EVENING AS A COLD FRONT PUSHES EAST OUT OF THE NORTHERN
PLAINS TOWARD THE AREA.
&&
.HYDROLOGY...
ISSUED AT 253 PM CDT SAT JUN 22 2013
HYDRO CONCERNS LINGER ACROSS TURKEY...UPPER IOWA...SOUTHERN HALF OF
THE KICKAPOO...BLACK...AND TURTLE CREEK. IN ADDITION...THE SMALL
STREAMS ACROSS ALLAMAKEE AND CLAYTON COUNTIES IN NORTHEAST IOWA...
AND CRAWFORD AND GRANT COUNTIES IN SOUTHWEST WISCONSIN.
FORTUNATELY IT LOOKS LIKE THE HEAVIEST RAIN POTENTIAL FOR TONIGHT
WILL BE MAINLY NORTH OF MOST OF THESE BASINS. HOWEVER THERE IS
CONCERN ON SUNDAY THAT THERE COULD BE ANOTHER ROUND OF HEAVY RAIN
THAT COULD AFFECT THE AREA ON SUNDAY AFTERNOON AND NIGHT. HOWEVER
DUE TO THE UNCERTAINTY ON THE SPEED OF THIS SYSTEM...RAINFALL
AMOUNTS ARE NOT CLEAR.
IN ADDITION TO THE SHORT TERM WATER CONCERNS...THERE IS A RIVER
FLOOD WATCH FOR THE MISSISSIPPI AT WABASHA...WINONA...AND
LA CROSSE. THESE RIVERS ARE EXPECTED TO GO ABOVE FLOOD STAGE UNTIL
AFTER JULY 1ST.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...BOYNE
LONG TERM...BOYNE
AVIATION...DAS
HYDROLOGY...BOYNE
FORECAST DISCUSSION FOR ROUTINE AFTERNOON FORECAST ISSUANCE
.SHORT TERM...TONIGHT AND SUNDAY
ISSUED AT 246 PM CDT SAT JUN 22 2013
THE LATEST RUC ANALYSIS AND SATELLITE/RADAR IMAGERY SHOW A
COMPLICATED WEATHER MAP THIS AFTERNOON ACROSS THE REGION. OUTFLOW
BOUNDARY FROM LAST NIGHTS STORMS REACHED INTO CENTRAL ILLINOIS AND
CENTRAL IOWA...BUT IS NOW RETURNING NORTHWARD INTO SOUTHERN
MINNESOTA. MEANWHILE...HIGH PRESSURE OVER ONTARIO IS PUSHING A WEAK
CANADIAN FRONT INTO CENTRAL WISCONSIN AND CENTRAL MINNESOTA.
LOOKING ALOFT...VARIOUS SHORTWAVE TROUGHS ARE PROGRESSING NORTHEAST
OVER THE NORTHERN MISSISSIPPI VALLEY AND THE UPPER PENINSULA. RADAR
IS PRETTY QUIET ACROSS THE REGION SO FAR THIS AFTERNOON...BUT THE
ATMOSPHERE IS STILL RECOVERING FROM LAST NIGHTS CONVECTION.
INSTABILITY IS BEGINNING TO BUILD OVER SOUTHERN MINNESOTA IN CLOSE
PROXIMITY TO THE RETURNING OUTFLOW BOUNDARY. LOW LEVEL CONVERGENCE
IS MAXIMIZED HERE...SO THIS BOUNDARY LOOKS TO BE THE FOCUS FOR THE
REST OF THE AFTERNOON AND HEADING INTO THE EVENING.
OBVIOUSLY...IMPACTS FROM POSSIBLE CONVECTION IS THE MAIN FORECAST
CONCERN IN THE SHORT TERM.
TONIGHT...THE LLJ WILL DEVELOP AGAIN AHEAD OF SHORTWAVE TROUGHS
EXTENDING FROM THE CENTRAL GREAT PLAINS TO LAKE SUPERIOR.
NAM/RUC/GFS SUGGEST MASS CONVERGENCE ALONG THE NOSE OF THE LLJ WILL
TAKE PLACE ACROSS CENTRAL OR SOUTHERN MINNESOTA...AND INTO WESTERN
WISCONSIN WHERE THE RETURNING OUTFLOW BOUNDARY/WARM FRONT WILL
RESIDE. AS INCREASING FLOW LIFTS OVER THIS BOUNDARY IN CONJUNCTION
WITH ELEVATED INSTABILITY OF 1000-2000 J/KG...ANTICIPATE ANOTHER MCS
TO DEVELOP OVER CENTRAL OR SOUTHERN MINNESOTA THIS EVENING BEFORE
TRACKING EAST ALONG THE BOUNDARY. THINK INSTABILITY WILL HAVE
RECOVERED ENOUGH BY THIS EVENING FOR ANY CONVECTION TO REACH CENTRAL
WISCONSIN OR EVEN THE FOX VALLEY BEFORE IT TURNS TO THE SOUTHEAST
LATE TONIGHT. LATEST MODELS ARE GENERALLY ALL OVER THE PLACE WITH
PRECIP TRENDS...SO CONFIDENCE IS RATHER LOW. BUT THE FRONT HAS BEEN
ACTIVE WITH MCS/S THE PAST SEVERAL NIGHTS...SO AS LONG AS
INSTABILITY DEVELOPS ALONG THE BOUNDARY THIS AFTERNOON...CANNOT RULE
OUT THE POSSIBILITY OF AN MCS DEVELOPING THIS EVENING. BIGGEST
THREAT WOULD BE HEAVY RAINFALL/FLOODING...BUT STRONG STRAIGHT LINE
WINDS AND SMALL HAIL COULD ALSO OCCUR IF INSTABILITY RECOVERS
ENOUGH. LOWS MAINLY IN THE 60S.
SUNDAY...MUCH OF THE DETAILS REVOLVE AROUND WHAT HAPPENS
TONIGHT...AND IF CONVECTION CAN LAY OUT ANOTHER OUTFLOW BOUNDARY
WHICH KEEPS THE REGION STABLE FOR MUCH OF THE DAY. IF THIS
OCCURS...MUCH OF THE MORNING INTO EARLY AFTERNOON MAY TURN OUT TO
BE DRY. DURING THE AFTERNOON THOUGH...A SHORTWAVE TROUGH MOVING
INTO NORTHWEST WISCONSIN WILL HELP SOUTHERLY FLOW STRENGTHEN AND
PUSH INSTABILITY NORTHWARD. REALLY TOUGH TO SAY HOW MUCH
INSTABILITY WILL BE PRESENT...DUE TO UNCERTAINTIES IN
HEATING...AND ALSO PROGGED SOUNDINGS APPEAR TO BE CONVECTIVELY
ADJUSTED. BUT WITH WIND FIELDS STRENGTHENING TOMORROW...FAIRLY
UNIDIRECTIONAL SHEAR CALLS FOR DAMAGING WINDS AND LARGE HAIL AS
THE MAIN THREATS. CENTRAL AND NORTH-CENTRAL WISCONSIN SHOULD HAVE
THE BEST CHANCE OF STORMS TOMORROW AFTERNOON AND WILL KEEP THE
HIGHEST POPS OVER THERE. WITH SOUTHERLY WINDS...TEMPS SHOULD REACH
MOSTLY IN THE MID TO UPPER 80S...PERHAPS A LITTLE LOWER OVER N-C
WISCONSIN.
.LONG TERM...SUNDAY NIGHT THROUGH SATURDAY
ISSUED AT 246 PM CDT SAT JUN 22 2013
SOUTHWEST UPPER FLOW AND SEVERAL WEAK FRONTAL BOUNDARIES WILL
KEEP THE THREAT OF PRECIPITATION IN THE FORECAST THROUGH THE
MIDDLE OF THE WEEK. A WEAK COLD FRONT WILL MOVE THROUGH SUNDAY
NIGHT AND SHOULD BE ACCOMPANIED WITH SHOWERS AND THUNDERSTORMS.
THERE COULD BE A BREAK IN THE ACTION MONDAY BEFORE THE FRONT LIFTS
SLOWLY NORTH AND PERHAPS STALL OVER THE FORECAST AREA TUESDAY AND
WEDNESDAY. A MORE SIGNIFICANT COLD FRONT SHOULD MOVE THROUGH
THURSDAY AND BE FOLLOWED BY DRY AND PLEASANT WEATHER FOR THE END
OF THE WEEK.
THERE ARE THREATS OF SEVERE THUNDERSTORMS MONDAY THROUGH WEDNESDAY
AFTERNOONS WITH HIGH CAPES AND MODERATE MID LEVEL WINDS. HIGH
PRECIPITABLE WATER VALUES AND SLOW MOVING STORMS ALSO COULD
PRODUCE EXCESSIVE RAINS. WILL MENTION IN THE HAZARDOUS WEATHER
OUTLOOK.
&&
.AVIATION...FOR 18Z TAF ISSUANCE
ISSUED AT 1236 PM CDT SAT JUN 22 2013
CONFIDENCE HAS NOT IMPROVED ANY IN THE FORECAST DETAILS OVER THE
NEXT 24 HOURS. PARTIAL CLEARING OCCURRING IN THE VICINITY OF
VARIOUS SHORTWAVE TROUGHS OVER MINNESOTA AND WESTERN WISCONSIN SUGGESTS
POTENTIAL FOR STORMS WILL INCREASE LATER THIS AFTERNOON IF THESE
TRENDS CONTINUE. IF STORMS DEVELOP...WOULD LIKELY IMPACT CENTRAL
AND NORTH-CENTRAL WISCONSIN. NOCTURNAL STORMS COULD ALSO REFIRE
ALONG A WARM FRONT AS IT LIFTS NORTH OVER MINNESOTA AND WISCONSIN
TONIGHT. IF THIS OCCURS...STORMS WOULD TRACK ALONG THE WARM FRONT
EAST-SOUTHEAST INTO NORTH-CENTRAL WISCONSIN AND POSSIBLY NORTHEAST
WISCONSIN LATE. UNCERTAINTIES REVOLVING AROUND LOCATION AND TIMING
OF STORMS IS TOO HIGH TO INCLUDE TSRA IN TAFS AT THIS TIME.
OTHERWISE...CIGS IMPROVING THIS AFTERNOON TO VFR.
&&
.MARINE...DENSE FOG IS THE PRIMARY CONCERN OVER LAKE MICHIGAN AS
WARM AND MOOIST AIR FLOWS NORTH OVER THE COLDER WATERS. DENSE FOG
WILL PROBABLY FORM TONIGHT ALONG THE LAKESHORE SOUTH OF STURGEON
BAY AND WILL LIKELY EXPAND NORTHWARD TONIGHT AND SUNDAY. THERE MAY
BE SOME DISSIPATION OF THE FOG SUNDAY AFTERNOON WHEN THE WIND
PICKS UP. THERE MAY BE PERIODS OF DENSE FOG THROUGH WEDNESDAY WITH
A POSSIBLE BREAK MONDAY AND MONDAY NIGHT.
.GRB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM.....MPC
LONG TERM......RDM
AVIATION.......MPC
MARINE.........RDM
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
1249 PM CDT SAT JUN 22 2013
.UPDATE...
ISSUED AT 1248 PM CDT SAT JUN 22 2013
CURRENTLY WATCHING A WARM FRONT ALONG THE MN/IA WARM FRONT FOR
THUNDERSTORM DEVELOPMENT THIS AFTERNOON. RAP PRODUCES
5000-5500J/KG OF 0-1KM ML MUCAPE ALONG THIS WARM FRONT WITH
INCREASING MOISTURE TRANSPORT/HEATING. ALSO...SIGNIFICANT 0-6KM
BULK SHEAR OF 35-40KT DEPICTED ALONG/NORTH OF THE FRONT. THINKING
THAT WITH HEATING AND WARM FRONTAL BOUNDARY MAKING A MOVE
NORTH...CONVECTION WILL FIRE ALONG THE FRONT WITH MOST NUMEROUS
SHRA/TS ACTIVITY FROM KFSD AND ALONG THE MN/IA BORDER...WITH
EASTERN FRINGES OF THIS CONVECTION GETTING INTO NORTHEAST
IA/SOUTHEAST MN LATE IN THE AFTERNOON. OF NOTE IS STRONG 0-1
MLCIN IN PLACE RIGHT NOW. FEEL THIS WILL EVENTUALLY ERODE THOUGH
AS CIRRUS SHIELD FROM THIS MORNING/S STORMS DISSOLVES AND SURFACE
HEATING GETS GOING. GIVEN THE ABOVE SIGNALS...POTENTIAL IS THERE FOR
DISCRETE SUPERCELLS WITH LARGE HAIL/WIND/ISOLATED TORNADO THREAT
MAINLY FOR PORTIONS OF SOUTHEAST MN/NORTHEAST IA.
&&
.SHORT TERM...(TODAY THROUGH SUNDAY)
ISSUED AT 349 AM CDT SAT JUN 22 2013
MAIN FORECAST CONCERNS THIS PERIOD...SHRA/TSRA CHANCES...HEAVY RAIN
AND SEVERE THREATS THRU THE PERIOD...TEMPERATURES.
DATA ANALYSIS AT 06Z HAD LOW PRESSURE OVER EASTERN CO WITH A
TROUGH TO THE NORTHEAST INTO THE UPPER MIDWEST. SEVERAL WEAKER WAVES
OF LOW PRESSURE ALONG THIS TROUGH/FRONT INTO WI/MI. TROUGH AND OLD
OUTFLOW BOUNDARIES REMAIN THE FOCUS FOR SHRA/TSRA DEVELOPMENT AGAIN
EARLY THIS MORNING AS THE LOW LEVEL JET AND MOISTURE TRANSPORT PUSH
AN AIRMASS WITH 1.5 TO 2 INCH PW/S NORTH/NORTHEAST INTO IA/MN/WI.
RATHER MASSIVE CONVECTIVE COMPLEX EARLY THIS MORNING FROM SOUTHERN
LK MI TO SOUTHERN MN AND EASTERN NEB...AROUND THE EDGE OF THE
STRONGER MID LEVEL CAPPING. UNDER THE CAPPING...EARLY MORNING TEMPS
IN THE MID 70S TO NEAR 80 ACROSS MUCH OF IA.
22.00Z MODELS LOOK TO HAVE INITIALIZED WELL...THOUGH NOT AS
SIMILARLY AS ONE WOULD LIKE. AS EXPECTED IN A FORECAST DOMINATED BY
MESO-SCALE FORCINGS AND CONVECTION ACROSS THE REGION...SOLUTIONS
OFFERING A VARIETY OF SENSIBLE WEATHER OUTCOMES FOR THE NEXT FEW
DAYS. DPROG/DT OF 500MB HGTS AT 22.00Z SHOWED THE MODEL RUNS OF
20.00Z AND 21.00Z VERIFIED QUITE WELL WITH THE LARGER SCALE FEATURES
OVER NOAM/EASTERN PAC. MOST OF THE EARLIER RUNS WERE A BIT WEAK WITH
SHORTWAVE FEATURES OVER THE CENTRAL CONUS TO GREAT LAKES AND WERE A
BIT HIGH WITH 500MB HGTS OVER THE UPPER MIDWEST. MODELS TRENDING
TOWARD A TIGHTER CONSENSUS TODAY THRU SUN...AT LEAST WITH THE
NORTHERN ROCKIES TROUGH AS IT LIFTS INTO THE NORTHERN PLAINS. TREND
IS A BIT STRONGER WITH TROUGHING AS IT LIFTS ACROSS THE NORTHERN
PLAINS TOWARD NORTHERN MN/WESTERN ONT TONIGHT/SUN. PLENTY OF DETAIL
DIFFERENCES WITH SMALLER SCALE FEATURES THRU THE SOUTHWEST FLOW
ACROSS THE CENTRAL PLAINS INTO UPPER MIDWEST AHEAD OF THE TROUGH.
CHECK OF OBS VS. MODEL DATA AT 06Z SHOWED MODELS TO BE REASONABLE
WITH THE SFC MASS FIELDS OVER THE CENTRAL CONUS...BUT SFC PRESSURE
FIELDS QUITE DISTURBED FROM EASTERN NEB TO WI BY ALL THE ONGOING
CONVECTION. PER WV IMAGERY...ECMWF LOOKS BEST WITH THE CENTRAL CONUS
SHORTWAVE DETAILS. MOST OF THE OTHERS LOOK TO SUFFER SOME FORM OF
CONVECTIVE FEEDBACK WITH COMPACT/STRONG VORTICITY MAXIMA OVER THE
NORTHERN PLAINS/UPPER MIDWEST. ECMWF/GEM/SREF LOOKED BETTER WITH
THE 00-06Z PRECIP OVER THE UPPER MIDWEST...NAM/GFS WERE TOO FAR
SOUTH WITH CONVECTION OVER IA. LOCAL/REGIONAL WRF MODELS CATCHING
ONTO CONVECTIVE EVOLUTION EARLY THIS MORNING. FIRST TO CATCH IT WERE
THE ARX-WRF AND EAST-ARW. GIVEN THE MODEL DIFFERENCES AND THEIR
IMPACTS ON THE SENSIBLE WEATHER THRU THE WEEKEND...SHORT TERM FCST
CONFIDENCE IS BELOW AVERAGE. GENERALLY FAVORED A MODEL/ENSEMBLE
CONSENSUS...WEIGHTED TOWARD THE NON GFS/NAM MODELS.
FAVORING THE SUITE OF LOCAL/REGIONAL HIGH-RES WRF MODELS...CONVECTION
WILL BE ONGOING ACROSS AT LEAST PORTIONS OF THE AREA THIS MORNING AS
THE LOW LEVEL JET/MOISTURE TRANSPORT/THETA-E CONVERGENCE VEERS ACROSS
MN/IA/WI. TRENDED SHRA/TSRA CHANCES TOWARD 70-80 PERCENT ACROSS MUCH
OF THE FCST AREA AT 12Z...THEN TRENDING DOWNWARD THRU THE MORNING.
ONLY CARRIED 20-40 PERCENT SHRA/TSRA CHANCES ACROSS MAINLY THE
NORTHWEST/NORTH PARTS OF THE FCST AREA THIS AFTERNOON...CLOSER TO THE
MAIN TROUGH/FRONTAL BOUNDARY AND THE MID LEVEL WARMING/CAPPING
BUILDING OVER THE SOUTHEAST HALF OF THE FCST AREA. WITH WHAT LOOKS
TO BE A BREAK LATER THIS MORNING/AFTERNOON...WILL NOT EXTEND FLASH
FLOOD WATCH BEYOND ITS CURRENT 17Z END TIME. MOISTURE TRANSPORT
INCREASES INTO THE AREA AGAIN THIS AFTERNOON WITH 2K-3K J/KG OF
CAPE AND SOUNDINGS SHOWING MINIMAL CAPPING...WILL LEAVE A 20-40
PERCENT SHRA/TSRA CHANCE THRU THE AFTERNOON. GIVEN THE /FAT/ CAPES...
STORMS THIS AFTERNOON/EARLY THIS EVENING WOULD POSE A THREAT OF
LARGE HAIL. APPEARS AREA MAY GET MORE OF A BREAK FROM THE WIDESPREAD
CONVECTION TONIGHT/EARLY SUN AS THE MAIN TROUGH/FRONT WITH ITS
CONVERGENCE/LIFT MOVE NORTH OF THE AREA. LEFT SHRA/TSRA CHANCES
TONIGHT MAINLY IN THE 20-40 PERCENT RANGE. DAY CREW WILL HAVE TO RE-
EVALUATE THE HYDRO SITUATION...WATCH TRENDS THRU THE DAY AND SEE
WHICH IF ANY OF THE MODELS ARE MORE CORRECT WITH CONVECTIVE EVOLUTION
THE NEXT 24-36HRS.
BY SUN AFTERNOON THE MAIN MID LEVEL TROUGH LIFTING INTO NORTHWEST MN
PUSHES THE SFC-850MB FRONT/TROUGH BACK TO THE SOUTHEAST. FORCING/
LIFT AHEAD OF THIS FEATURE PUSHING INTO THE AIRMASS OVER THE AREA
WITH SOME 2K-3K J/KG MU CAPE AND PW VALUES OF 1.5 TO 2 INCHES SHOULD
IGNITE ANOTHER ROUND OF SHRA/TSRA WITH HEAVY RAIN AND SEVERE
POTENTIAL. GIVEN THE RECENT RAINS APPEARS ANOTHER FLASH FLOOD WATCH
MAY BE NEEDED SUN AFTERNOON/EVENING.
HIGH TEMPERATURES TODAY/SUN REMAIN TRICKY...BASED ON WHEN CONVECTION
WOULD CLEAR THE AREA AND HOW QUICKLY CLOUDS THIN/CLEAR AND ALLOW
FOR SOME SUNSHINE. GIVEN THE UNCERTAINTIES...STAYED NEAR THE MODEL/
ENSEMBLE CONSENSUS FOR HIGHS/LOWS TODAY THRU SUN.
.LONG TERM...(SATURDAY NIGHT THROUGH FRIDAY)
ISSUED AT 349 AM CDT SAT JUN 22 2013
MODEL CONSENSUS CONTINUES TO IMPROVE FOR SUN NIGHT THRU MON NIGHT AS
THE MID LEVEL TROUGH LIFTS INTO ONT AND HGTS RISE OVER THE REGION.
HOWEVER THE LOWER LEVEL PATTERN REMAINS ACTIVE/UNSETTLED...WITH
PLENTY OF MODEL DETAIL DIFFERENCES. FCST CONFIDENCE IN THIS PERIOD
REMAINS BELOW AVERAGE. THE PASSING MID LEVEL TROUGH PUSHES THE WEAK
SFC TROUGH/FRONT INTO ACROSS THE AREA SUN NIGHT. SHRA/TSRA CHANCES IN
THE 50-70 PERCENT RANGE SUN NIGHT LOOK REASONABLE. GIVEN THE
FORCING...STRONG INSTABILITY AND INCREASED WINDS/SHEAR ALOFT...TSRA
SUN NIGHT COULD BE SEVERE WITH THREATS OF WINDS AND HAIL. THE
TROUGH/FRONT FROM SUN/AFTERNOON/EVENING LIFTS BACK NORTH ALREADY ON
ON MON...PROVIDING FOCUS FOR CONVERGENCE/LIFT AND SHRA/TSRA
FORMATION...THIS AS MODELS SHOW POTENTIAL FOR ONE OR MORE SHORTWAVES
TO BE RIPPLING THRU THE FLOW AND ACROSS THE REGION. CONTINUED 20-40
PERCENT SHRA/TSRA CHANCES MON. LOW LEVEL JET/MOISTURE TRANSPORT/
THETA-E CONVERGENCE INCREASE INTO THE AREA MON NIGHT AS THIS BOUNDARY
LIFTS NORTH ACROSS THE AREA. CARRIED 30-50 PERCENT SHRA/TSRA CHANCES
MON NIGHT.
GIVEN THE LOWER CONFIDENCE ON THE CONVECTIVE DETAILS...USED A
MODEL/ENSEMBLE CONSENSUS FOR LOWS/HIGHS SUN NIGHT THRU MON NIGHT.
WITH ALL THE SHORT TERM CONCERNS AND UNCERTAINTIES...NOT MUCH TIME
SPENT LOOKING AT THE DAY 4-7 PERIOD. MEDIUM RANGE MODEL RUNS OF
22.00Z DO OFFER SOME CONSENSUS FOR A FLAT WEST TO SOUTHWEST FLOW
ALOFT OVER THE CENTRAL CONUS TUE/WED...WITH SHORTWAVES TO BE
RIPPLING THRU THIS FLOW AND ACROSS THE REGION. LONGER TERM FCST
CONFIDENCE AVERAGE. WITH THE MOIST/UNSTABLE AIRMASS IN PLACE AND ONE
OR MORE BOUNDARIES FLOATING AROUND THE REGION...SHRA/TSRA CHANCES
LOOK TO CONTINUE TUE THRU AT LEAST WED NIGHT. BY THU MODELS POINT TO
RIDGING BUILDING OVER THE WESTERN CONUS AND THE FLOW ALOFT OVER THE
UPPER MIDWEST BECOMING NORTHWEST FOR THU/FRI. THIS NORTHWEST FLOW
WOULD DRIVE SOME DRIER/COOLER AIR FROM SOUTH CENTRAL CAN/NORTHERN
PLAINS...AND DECREASING SHRA/TSRA CHANCES...INTO THE AREA FOR THE
LATER PARTS OF THE WEEK. MODEL/ENSEMBLE CONSENSUS HIGHS/LOWS FOR
TUE THRU FRI LOOK WELL TRENDED FOR NOW.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON)
ISSUED AT 1248 PM CDT SAT JUN 22 2013
EXPECTING SCATTERED THUNDERSTORMS TO FIRE THIS AFTERNOON ALONG A
WARM FRONT SITUATED ALONG THE IA/MN BORDER. PLAN ON THE BULK OF THIS
THUNDERSTORM ACTIVITY TO EXTEND FROM KFSD THROUGH SOUTH-CENTRAL
MN...WITH EASTERN FRINGES OF THIS CONVECTION REACHING TOWARD THE
MISSISSIPPI RIVER INCLUDING KRST/KLSE TAF SITES. THE WARM FRONT IS
EXPECTED TO PUSH NORTH OF THE AREA AFTER MIDNIGHT...TAKING THE
THUNDERSTORM ACTIVITY WITH IT. BOTTOM LINE...INCLUDED VCTS BKN030-035CB
IN THE KRST/KLSE TAFS FROM 21Z THROUGH 06Z. OTHER THAN SOME 6SM
BR IN THE 08-13Z TIME FRAME...EXPECTING VFR CONDITIONS THEN TO
PREVAIL THROUGH 18Z SUNDAY. SHRA/TS LOOKING LIKELY AGAIN SUNDAY
AFTERNOON/EVENING AS A COLD FRONT PUSHES EAST OUT OF THE NORTHERN
PLAINS TOWARD THE AREA.
&&
.HYDROLOGY...TONIGHT INTO SATURDAY
ISSUED AT 349 AM CDT SAT JUN 22 2013
A FLASH FLOOD WATCH REMAINS IN EFFECT THROUGH NOON TODAY. CONVECTION
SHOULD BE WANING/ENDING THRU THE MORNING...WITH PLENTY OF
UNCERTAINTY CONCERNING REDEVELOPMENT AND EVOLUTION THIS AFTERNOON
AND EVENING. HEAVY RAINS FROM FRI EVENING/EARLY THIS MORNING WERE
NOT AS WIDESPREAD AS THE NIGHT BEFORE. CONVECTION THIS AFTERNOON/
EVENING APPEARS AS THOUGH IT MAY BE MORE SCATTERED AND PROGRESSIVE
THUS WILL NOT BE EXTENDING THE FLASH FLOOD WATCH AT THIS TIME.
MAIN FORCING/LIFT LOOK TO LIFT NORTH OF THE FCST AREA FOR TONIGHT/
SUN MORNING...BUT STRONGER FORCING /IN THE FORM OF A PASSING MID
LEVEL TROUGH AND APPROACHING SFC-850MB TROUGH/FRONT/ MOVES BACK
INTO THE AREA SUN AFTERNOON/EVENING. MORE WIDESPREAD CONVECTION...
CAPABLE OF PRODUCING HEAVY RAINS...LOOKS LIKELY AS THESE FEATURES
PASS. APPEARS A FLASH FLOOD WATCH MAY BE NEEDED AGAIN SUN
AFTERNOON INTO SUN NIGHT.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
UPDATE...DAS
SHORT TERM...RRS
LONG TERM....RRS
AVIATION...DAS
HYDROLOGY....RRS
AREA FORECAST DISCUSSION
NWS GREEN BAY WI
1237 PM CDT SAT JUN 22 2013
UPDATED AVIATION PORTION FOR 18Z TAF ISSUANCE
.SHORT TERM...TODAY...TONIGHT...AND SUNDAY
ISSUED AT 442 AM CDT SAT JUN 22 2013
CONTINUE WITH ISSUES ON WHERE AND WHEN CONVECTION WILL AFFECT
AREA. WATER VAPOR IMAGERY SHOWING NUMBER OF DISTURBANCES MOVING
THROUGH SOUTHWEST FLOW ALOFT OVER UPPER MIDWEST. CONVECTION
ASSOCIATED WITH THESE DISTURBANCES CURRENTLY EXTENDS OVER SOUTHERN
WI THROUGH MN AND NEBRASKA. MAIN ISSUES TONIGHT WITH THE
CONVECTION...HEAVY RAIN. IR IMAGERY SHOWING WARMING TOPS ATTM WITH
DOWNWARD TREND EXPECTED TO CONTINUE INTO THE MORNING HOURS. OVER
NORTHEAST WI...STABLE AIR FILTERED SOUTH BEHIND BOUNDARY DROPPING
SOUTH OUT OF LAKE SUPERIOR DURING THE EVENING. MODEL OF CHOICE
QUESTIONABLE...WHILE GFS AND TO SOME EXTENT EC APPEARED TO BE
DOING WELL AT 6Z WITH CONVECTIVE TRENDS...THEY QUICKLY LOSE
REALITY AS MOVE INTO THIS MORNING. HAVE TRENDED TOWARDS CURRENT
RADAR TRENDS AND HRRR WHICH BRINGS WAINING CONVECTION NORTH INTO
CENTRAL AND NORTH CENTRAL WI THIS MORNING. THUS WILL GO HIGH
CHANCE OR LIKELY OVER THESE LOCATIONS FOR FIRST PART OF DAY.
REMAINDER OF AREA...LOWER CHANCE POPS THROUGH THE DAY. HRRR
SUGGEST LIMITED PCPN THROUGH AFTERNOON. THIS MAKES SENSE AS BEST
FORCING/ ISENTROPIC LIFT WEST OVER SOUTHERN MN THIS
AFTERNOON...EVENING. MODELS CONTINUE TO TRY AND BRING WARM FRONT
NORTH THROUGH THE AREA TONIGHT. WITH UNCERTAINTY...WILL STICK TO
CHANCE POPS THROUGH SUN. COLD FRONT APPROACHES STATE LATE IN DAY
SUN AS MAIN UPPER WAVE LIFTS NORTHEAST THROUGH HIGH PLAINS.
TRENDED POPS HIGHER WEST GIVEN PROXIMITY OF FRONT.
AGAIN OVERNIGHT STORMS PRODUCED SIG PCPN AS HAVE PLENTY OF
MOISTURE TO WORK WITH WITH PW`S IN 1.5 TO 2.0 INCH RANGE. THIS TO
CONTINUE INTO SUNDAY. PLENTY OF INSTABILITY AROUND THROUGH THE
PERIOD...THOUGH SHEAR IS LIMITED AT LEAST UNTIL SUN...WHEN MODELS
SUGGEST INCREASES TO NR 40 KTS. WILL CONTINUE TO HIGHLIGHT HEAVY
RAIN POTENTIAL AS MAIN ISSUE...WITH STRONG DAMAGING WIND THREAT
POSSIBLE TODAY AND TONIGHT.
GIVEN LOW CLOUDS/CLOUDS EXPECTED FOR FIRST HALF OF DAY AND
EASTERLY COMPONENT OF WIND...HAVE DROPPED HIGHS A GOOD 5 DEGS
TODAY. HAVE NOT MADE ANY SIG CHANGE TO SUN ATTM DUE TO UNCERTAINTY
ON CONVECTION.
.LONG TERM...SUNDAY NIGHT THROUGH FRIDAY
ISSUED AT 442 AM CDT SAT JUN 22 2013
UPPER RIDGE WILL GRADUALLY RETROGRADE WESTWARD INTO THE WESTERN
UNITED STATES. THIS WILL EVENTUALLY CHANGE THE SOUTHWEST FLOW
PATTERN TO A NORTHWEST FLOW PATTERN...BRINGING COOLER TEMPERATURES
AND LOWER HUMIDITY BY THE END OF THE WEEK.
CONSIDERING MODELS ARE HAVING TOUGH TIME OVER THE LAST FEW DAYS
IN THE PLACEMENT OF CONVECTION AND LOCALLY HEAVY RAIN...LOWER
THAN NORMAL CONFIDENCE IN THE DETAILS OF THE FORECAST AS THE MODELS
CONTINUE TO SHOW SEVERAL COMPLEXES MOVING ACROSS THE WESTERN GREAT
LAKES EARLY TO MIDDLE OF NEXT WEEK. THEREFORE...WILL CONTINUE CHANCES
OF SHOWERS AND THUNDERSTORMS EACH DAY THROUGHOUT THE PERIOD. SOME
INDICATIONS BY THE MODELS THAT MONDAY COULD END UP BEING DRIER THAN
ADVERTISED...BUT WILL BELIEVE IT WHEN I SEE IT.
STILL THE POTENTIAL FOR SEVERE WEATHER AND LOCALLY HEAVY EARLY TO
MIDDLE PORTIONS OF NEXT WEEK. HAZARDOUS WEATHER OUTLOOK HAS THIS
MENTIONED ALONG WITH THE UNCERTAINTY IN TIMING. ONLY MINOR CHANGES
MADE TO THE EXTENDED FORECAST ON A FEW DAYS...MORE COORDINATION
PURPOSES.
&&
.AVIATION...FOR 18Z TAF ISSUANCE
ISSUED AT 1236 PM CDT SAT JUN 22 2013
CONFIDENCE HAS NOT IMPROVED ANY IN THE FORECAST DETAILS OVER THE
NEXT 24 HOURS. PARTIAL CLEARING OCCURRING IN THE VICINITY OF
VARIOUS SHORTWAVE TROUGHS OVER MINNESOTA AND WESTERN WISCONSIN SUGGESTS
POTENTIAL FOR STORMS WILL INCREASE LATER THIS AFTERNOON IF THESE
TRENDS CONTINUE. IF STORMS DEVELOP...WOULD LIKELY IMPACT CENTRAL
AND NORTH-CENTRAL WISCONSIN. NOCTURNAL STORMS COULD ALSO REFIRE
ALONG A WARM FRONT AS IT LIFTS NORTH OVER MINNESOTA AND WISCONSIN
TONIGHT. IF THIS OCCURS...STORMS WOULD TRACK ALONG THE WARM FRONT
EAST-SOUTHEAST INTO NORTH-CENTRAL WISCONSIN AND POSSIBLY NORTHEAST
WISCONSIN LATE. UNCERTAINTIES REVOLVING AROUND LOCATION AND TIMING
OF STORMS IS TOO HIGH TO INCLUDE TSRA IN TAFS AT THIS TIME.
OTHERWISE...CIGS IMPROVING THIS AFTERNOON TO VFR.
&&
.GRB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM.....TE
LONG TERM......ECKBERG
AVIATION.......MPC