Forecast Discussions mentioning any of
"HRRR" "RAP" "RR" "RUC13" "RUC" received at GSD on 06/20/13
AREA FORECAST DISCUSSION
NWS DENVER/BOULDER CO
1157 AM MDT TUE JUN 18 2013
.UPDATE...
WEAK UPPER LEVEL SHORTWAVE MOVING OUT OF UTAH IS HELPING TO FIRE
EARLY THUNDERSTORMS THAT HAVE ALREADY MOVED INTO THE LOWER
FOOTHILLS. 12Z DENVER SOUNDING WAS FAIRLY IMPRESSIVE BUT GPS
PRECIPITABLE WATER TRENDS HAVE BEEN DOWNWARD THIS MORNING THOUGH
NOW LEVELING OFF NEAR 0.6 INCHES WHICH IS DOWN A BIT FROM THE
SOUNDING. SURFACE DEWPOINTS HAVE ALSO COME DOWN SOME ON THE PLAINS
WITH UPPER 40S TO LOWER 50S GENERALLY. SOUTHEAST FLOW HAS PRODUCED
A MODEST DENVER CYCLONE WITH THE CONVERGENCE LINE NEAR DIA. NO
RECENT HRRR RUN BUT EARLIER RUNS SHOWED THE EARLIER DEVELOPMENT OF
CONVECTION THAT WE ARE SEEING NOW. THIS ALSO AGREES WITH HI
RESOLUTION NCEP MODEL RUNS. STILL EXPECT THE MOST ORGANIZED
ACTIVITY TO BE GENERALLY EAST OF DIA TO GREELEY AND POSSIBLY
FAVORING MORE SOUTHERN AREAS OF THE PLAINS NEAR AND SOUTH OF I70
WHERE MOISTURE LOOKS DEEPER. ENOUGH SHEAR FOR SOME SUPERCELL
DEVELOPMENT AND ADDED ISOLATED TORNADOES TO THE HWO. WITH THE
DENVER CYCLONE CANNOT ELIMINATE SAME THREAT NEAR DIA ALTHOUGH AT
THIS POINT LOOKS TO BE ON THE LOWER THREAT END.
&&
.AVIATION...MOVED CHANCE OF STORMS UP A COUPLE OF HOURS BASED ON
ITEMS NOTED ABOVE. WINDS WILL BE A BIT TRICKY BUT AFTER
COORIDNATION WITH CWSU WE SETTLED ON DCVZ BOUNDARY SLIPPING BY
AIRPORT.
&&
.HYDROLOGY...SOME BRIEF HEAVY RAIN IS POSSIBLE MAINLY EAST OF
DENVER WITH STORMS FARTHER EAST POSSIBLY PRODUCING MORE DECENT
RAINS. RIGHT NOW ANY FOOTHILLS STORMS NOT LIKELY TO BE WORRISOME
FOR BURN AREAS.
&&
.PREV DISCUSSION... /ISSUED 319 AM MDT TUE JUN 18 2013/
SHORT TERM...AN UPPER LEVEL LOW WILL MOVE OVER THE PACIFIC
NORTHWEST TODAY. THIS WILL PUSH THE WEAK RIDGE THAT`S BEEN OVER
COLORADO EAST. THERE IS A SHORT WAVE SHOWING UP ON WATER VAPOR
SATELLITE IMAGERY OVER UTAH. IT WILL MOVE ACROSS COLORADO THIS
AFTERNOON AND EVENING...HELPING TO TRIGGER SHOWERS AND
THUNDERSTORMS.
MOISTURE WILL INCREASE TODAY WITH PRECIPITABLE WATER VALUES 0.10 TO
0.25 INCHES HIGHER THAN YESTERDAY WITH READIES RANGING FROM 0.60 TO
1.00 INCHES EAST OF THE FOOTHILLS. THIS INCREASE IN MOISTURE IN
ADDITION TO THE SHORT WAVE IS EXPECTED TO BRING MORE SHOWERS AND
STORMS TODAY. BEST CHANCE FOR SEVERE WEATHER WILL BE EAST OF LINE
FROM GREELEY TO DIA WHERE CAPES WILL BE 1000-2000 J/KG. STILL ENOUGH
SHEAR IN PLACE FOR A FEW SUPER CELL THUNDERSTORMS. IN THE FOOTHILLS
AND ALONG THE URBAN FRONT RANGE CORRIDOR...CAPES WILL BE 500-1000
J/KG. HIGHS TODAY WILL BE IN THE SAME BALL PARK AS YESTERDAY WITH
TEMPERATURES IN THE LOWER TO MID 80S.
MUCH DRIER AIR WILL MOVE IN FROM THE WEST TONIGHT AS WINDS TURN
SOUTHWESTERLY. THIS WILL BRING CONVECTION TO AN END FROM WEST TO
EAST. THE DRIER AIR WILL ALLOW LOWS TO DROP INTO THE UPPER 40S TO
LOWER 50S TONIGHT WITH 30S IN THE MOUNTAIN VALLEYS.
LONG TERM...WEST TO SOUTHWEST FLOW ALOFT WILL COVER COLORADO
WEDNESDAY THROUGH THURSDAY NIGHT...WITH AN UPPER RIDGE AXIS EAST
OF COLORADO. THE SYNOPTIC SCALE ENERGY IS PROGGED TO BE BENIGN
ALL FOUR PERIODS. THE BOUNDARY LAYER WINDS WILL ADHERE TO NORMAL
DIURNAL PATTERNS FOR THE MOST PART WEDNESDAY INTO EARLY THURSDAY.
A WEAK SURGE OF COOLER AIR IS EXPECTED TO MOVE INTO THE CWA BEFORE
NOON THURSDAY WITH ASSOCIATED WEAK UPSLOPE WINDS. BY THURSDAY
NIGHT...NORMAL PATTERNS RETURN. THE CROSS SECTIONS SHOW MINIMAL
MOISTURE OVER THE CWA WEDNESDAY THROUGH THURSDAY NIGHT. THE
BOUNDARY LAYER DEW POINT PROGGS SHOW ALL BUT THE FAR EAST OF THE
CWA IN PRETTY DRY READINGS...MOSTLY UNDER 40S F ALL FOUR PERIODS.
THERE ARE SOME 40S TO LOWER 50S F READINGS OVER THE BORDER AREAS
WEDNESDAY INTO WEDNESDAY EVENING...THEN THEY DECREASE AFTER THAT.
THE ONLY CAPE IS PROGGED OVER THE FAR EASTERN BORDER AREA LATE DAY
WEDNESDAY AND LATE DAY THURSDAY. VALUES ARE NOT SIGNIFICANT. THERE
IS ONLY A TAD OF MEASURABLE RAINFALL PROGGED ON THE QPF FIELDS OF
THE ECMWF ONLY LATE DAY WEDNESDAY AND LATE DAY THURSDAY. WILL GO
WITH NO POPS. FOR TEMPERATURES...WEDNESDAY`S HIGHS ARE ARE 3-6 C
WARMER THAN TODAY`S. THURSDAY`S HIGHS COOL OFF A TAD...1-2 C FROM
WEDNESDAY`S. FOR THE LATER DAYS...FRIDAY THROUGH MONDAY...THE FLOW
ALOFT STAYS WEST-SOUTHWESTERLY. THERE IS MINIMAL MOISTURE...AND
ABOVE NORMAL TEMPERATURES SATURDAY THROUGH MONDAY.
AVIATION...THERE ARE LOW CLOUDS OVER SOUTHEAST WYOMING AND FAR
NORTHERN COLORADO AT THIS TIME. JUST A SLIGHT CHANCE OF THEM MAKING
IT TO THE DENVER AREA...WILL MENTION A FEW AT 2000 FEET IN THE TAFS
FOR THE SLIGHT CHANCE OF THEM MAKING IT INTO THE DENVER AREA. GUSTY
SOUTHERLY WINDS WILL DEVELOP AROUND 17Z WITH GUSTS TO 30 KNOTS
POSSIBLE. SCATTERED THUNDERSTORMS WILL DEVELOP AFTER 20Z. HEAVY
RAIN...HAIL AND OUTFLOW WINDS TO 40 KNOTS WILL BE POSSIBLE WITH THE
STRONGEST STORMS. THE THREAT FOR STORMS WILL END AROUND 02Z.
HYDROLOGY...SIMILAR CONDITIONS WILL PREVAIL AS THE PREVIOUS
AFTERNOONS WITH ISOLATED TO SCATTERED THUNDERSTORMS EXPECTED OVER
THE BURN SCARS. THERE MAY BE SHORT LIVED HEAVY RAIN...BUT THE THREAT
FOR PROLONGED HEAVY RAIN OVER THE BURN AREAS WILL REMAIN VERY LOW.
&&
.BOU WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...SZOKE
LONG TERM....99
AVIATION...99
AREA FORECAST DISCUSSION
NWS PUEBLO CO
1144 AM MDT TUE JUN 18 2013
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 342 AM MDT TUE JUN 18 2013
...SEVERE WEATHER LIKELY THIS AFTERNOON ESPECIALLY NORTHERN EL PASO
COUNTY...
CURRENTLY...
AN MESOSCALE CONVECTIVE VORTICITY CENTER WAS CLEARLY SEEN IS RADAR
IMAGERY SPINNING JUST NE OF THE FAR NE CO BORDER EARLY THIS MORNING
(3 AM). CONVECTIVE OUTFLOW WITH THIS WAS DROPPING SWD ACROSS EC CO.
OTHER CONVECTIVE COMPLEXES WERE NOTED OVER NE NM. A FE LIGHT SHOWERS
WERE NOTED ALONG THE I-25 CORRIDOR AND THE SE PLAINS. DWPTS OVER THE
REGION WERE GENERALLY IN THE 50S OVER THE PLAINS...WITH 30S AND 40S
ELSEWHERE.
TODAY...
I SEE PRETTY STRONG SIGNALS IN THE GUIDANCE TODAY INDICATING THAT WE
MAY SEE A RATHER IMPRESSIVE ROTATING STORM FORM ON THE PALMER DIVIDE
IN THE GENERAL AREA OF DOUGLAS/ELBERT/EL PASO COUNTY AND MOVE
SOUTHEAST ACROSS NE EL PASO COUNTY...INTO LINCOLN COUNTY AND THEN
THE GREATER LA JUNTA REGION LATER IN THE EVENING. THE
NAM...GFS...AND RAP ALL SHOW THIS SAME GENERAL SIGNAL. ALTHOUGH
LARGE SCALE KINEMATICS ARE NOT ALL THAT IMPRESSIVE...SIMULATIONS
SHOW LOCAL BACKING OF THE LLVL WINDS OVER THE PALMER DVD LATE THIS
AFTERNOON...AND THIS LOCAL BACKING OF THE WINDS WILL ENHANCE THE
LLVL SHEAR. RATHER STRONG SE SFC INFLOW IS PRGD (AND MODELS HAVE
BEEN SHOWING THIS FOR DAYS) SO EXPECT STORM WILL BE INFLOW-DOMINANT
FOR A GOOD PART OF ITS LIFE. THE HODOGRAPH IS CURVED BUT THE OVERALL
MAGNITUDE IS NOT STRONG. CAPE IS PROJECTED TO BE ABOUT 1000-1500
J/KG AND TEMPS AT 500 ARE AROUND -9 TO -10C.
WITH THAT SAID...THE HI-RES DATA (SPC SSEO...NSSL WRF...LOCAL
WRF...IS NOT AS AGGRESSIVE AS THE OTHER GUIDANCE. THEY DO SHOW A WEAK
ROTATING STORM THIS REGION BUT MOVE IT OFF QUICKLY TO THE
EAST-SOUTHEAST.
GIVEN THE TIME OF THE YEAR...PAST HISTORY THE LAST COUPLE OF
DAYS...A WEAK SHORT WAVE MOVING ACROSS DURING PRIME HEATING...THE
LEFT FRONT QUAD OF THE SUBTROPICAL JET OVER EC CO...AND THE FACT
THIS WILL BE THE LAST DAY OF STRONGER CONVECTION OVER THE REGION...I
DO BELIEVE WE WILL SEE SOME SEVERE STORMS OVER THE REGION. I HAVE
MENTIONED SEVERE IN THE GRIDDS AND SPC HAS THE AREA OUTLOOKED FOR
TODAY. BASED ON WHAT I HAVE SEEN...THE MOST ORGANIZED SEVERE SHOULD
BE IN THE N EL PASO COUNTY REGION...AS THERE IS THE POSSIBILITY OF
SIGNIFICANT SEVERE HAIL...DAMAGING WINDS AND A LOW SUPERCELL TORNADO
THREAT THIS REGION. I BELIEVE THERE WILL PRIMARILY BE A WIND THREAT
AND MARGINAL SEVERE HAIL THREAT FARTHER SOUTHEAST OVER THE GREATER
LA JUNTA REGION LATER THIS EVENING.
THERE WILL ALSO BE A SLIGHT CHANCE OF SOME LOCALLY HEAVY RAIN OVER
THE WALDO...WHICH MAY CAUSE FLASH FLOODING. GIVEN THE DWPTS...AND
THE FACT THAT STORMS SHOULD BE MOVING...A FLASH FLOOD WATCH IS NOT
WARRANTED AT THIS TIME.
A LOT OF PEOPLE WILL BE EXPOSED ACROSS NORTHERN EL PASO COUNTY LATER
THIS AFTERNOON ASSOCIATED WITH THE BLACK FOREST FIRE MOP-UP
OPERATIONS. LIGHTNING AND LARGE HAIL...WITH THE POSSIBILITY OF FLASH
FLOODING...AND THE VERY SLIGHT CHANCE OF A TORNADO...COULD AFFECT
THESE FOLKS LATER THIS AFTERNOON AND EARLY EVENING.
TONIGHT...
CONVECTION WILL LAST INTO THE EVENING HOURS...WITH MOST IF NOT ALL
OF THE ACTIVITY OUT OF THE REGION BY MIDNIGHT. MUCH DRIER AND WARMER
AIR ALOFT WILL BE MOVING IN LATE TONIGHT.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 342 AM MDT TUE JUN 18 2013
...DANGEROUS FIRE WEATHER CONDITIONS THROUGH THE EXTENDED...
MODELS IN GOOD AGREEMENT THROUGH THE WEEKEND WITH A SLOW MOVING
UPPER LOW OVER THE PACIFIC NORTHWEST AND RIDGE ACROSS THE CENTRAL
CONUS. THIS WILL PUT THE ROCKIES UNDER BROAD SOUTHWESTERLY FLOW
LEADING TO DANGEROUS FIRE WEATHER CONDITIONS ACROSS THE REGION.
WEDNESDAY...STRONG SOUTHWESTERLY FLOW WILL PUSH INTO THE ROCKIES
BY WEDNESDAY MORNING AND SPREAD ACROSS THE EASTERN PLAINS THROUGH
THE AFTERNOON. STRONG MIXING WILL HELP WARM TEMPERATURES INTO THE
MID TO UPPER 90S FOR MUCH OF THE LOWER ELEVATIONS ALONG WITH
DROPPING HUMIDITY VALUES TO LESS THAN 10 PERCENT. WIDESPREAD
SOUTHWEST SURFACE WINDS IN EXCESS OF 20 KTS ARE LIKELY WHICH WILL
LEAD TO THE DANGEROUS FIRE WEATHER CONDITIONS. THE MAIN AREAS OF
CONCERN ARE THE MOUNTAIN AREAS...SAN LUIS VALLEY AND I-25
CORRIDOR. HAVE UPGRADED THE FIRE WEATHER WATCH TO A RED FLAG
WARNING FOR WEDNESDAY AFTERNOON INTO THE EVENING. CRITERIA ARE
BEING MET ACROSS THE PLAINS...BUT FUELS HAVE BEEN LISTED AS NOT
CRITICAL AND AREAS OUT EAST NEAR THE KANSAS BORDER HAVE SEEN
ABUNDANT RAINFALL...SO HAVE NOT INCLUDED THESE AREAS. ALSO REMOVED
POPS FOR WEDNESDAY AFTERNOON AND EVENING OUT NEAR THE KANSAS
BORDER. THE LATEST RUNS OF THE GFS AND NAM HAVE THE DRYLINE MIXING
WELL OUT INTO KANSAS WITH DRY CONDITIONS ACROSS COLORADO.
THURSDAY AND FRIDAY...THE UPPER LOW OVER THE PACIFIC NORTHWEST
WILL SLOWLY DRIFT EAST WITH THE STRONG SOUTHWESTERLY FLOW
CONTINUING ACROSS COLORADO. CONTINUED VERY DANGEROUS FIRE WEATHER
CONDITIONS WILL PERSIST...ESPECIALLY OVER THE MOUNTAIN AREAS AND
ADJACENT PLAINS WHERE MIXING WILL BE GREATEST AND FUELS MOST
CRITICAL. HAVE ISSUED A FIRE WEATHER WATCH FOR THE MOUNTAINS...SAN
LUIS VALLEY AND EL PASO COUNTY FOR THURSDAY...AND WILL LIKELY NEED
TO DO THE SAME FOR FRIDAY IN THE FUTURE. AFTERNOON HIGH
TEMPERATURES WILL REMAIN HOT WITH UPPER 90S TO LOWER 100S EXPECTED
ACROSS THE PLAINS. NO SHOWER OR THUNDERSTORM ACTIVITY IS EXPECTED.
THE PATTERN BEGINS TO SHIFT THIS WEEKEND WITH THE UPPER LOW
LIFTING NORTHEAST INTO SOUTH CENTRAL CANADA. SOUTHWESTERLY FLOW
WILL CONTINUE...HOWEVER MOISTURE WILL BEGIN TO DRAW NORTHWARD INTO
THE FAR SOUTHEASTERN PLAINS. THERE WILL BE A CONTINUED FIRE
WEATHER THREAT OVER THE MOUNTAINS AND SAN LUIS VALLEY THROUGH THE
WEEKEND INTO EARLY NEXT WEEK. THE GFS AND ECMWF BOTH DEVELOP DAILY
THUNDERSTORMS OVER NORTHERN NEW MEXICO AND LIFT THEM NORTHEAST
INTO THE FAR SOUTHEASTERN PLAINS. HAVE LOW POPS GENERALLY ALONG
THE NEW MEXICO BORDER THROUGH THE WEEKEND AS THE THUNDERSTORMS
MOVE INTO THE CENTRAL PLAINS AND CLIP OUR FAR SOUTHEAST ZONES.
TEMPERATURES WILL REMAIN WARM WITH 90S ACROSS THE LOWER ELEVATIONS
INTO EARLY NEXT WEEK. MOZLEY
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON)
ISSUED AT 1140 AM MDT TUE JUN 18 2013
NOT MUCH CHANGE MADE TO LATEST TAFS. KCOS HAS THE BIGGEST THREAT
OF BEING HIT BY SEVERE THUNDERSTORMS TODAY SO ADDED GS TO THE TAF.
KPUB HAS A SLIGHTLY LOWER PROBABILITY OF BEING DIRECTLY IMPACTED
BY TS...BUT HAS A HIGH PROBABILITY OF BEING AFFECTED BY GUSTY
OUTFLOW WINDS. HAVE INTRODUCED A TEMPO GROUP INTO THE TAF TO
REFLECT THAT POTENTIAL. KALS WILL SEE MORE HIGH BASED
THUNDERSTORMS TODAY WHICH ARE MORE LIKELY TO MISS THE TERMINAL.
GUSTY OUTFLOW WINDS WILL BE POSSIBLE THERE AS WELL...THOUGH WITH
LESS OF A THREAT WILL MONITOR LATEST RADAR TRENDS AND MAKE
ADJUSTMENTS AS NEEDED.
&&
.PUB WATCHES/WARNINGS/ADVISORIES...
RED FLAG WARNING FROM 11 AM TO 8 PM MDT WEDNESDAY FOR COZ220>227.
FIRE WEATHER WATCH FROM THURSDAY MORNING THROUGH THURSDAY
EVENING FOR COZ220>227.
&&
$$
SHORT TERM...HODANISH
LONG TERM...MOZLEY
AVIATION...KT
AREA FORECAST DISCUSSION
NWS PUEBLO CO
417 AM MDT TUE JUN 18 2013
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 342 AM MDT TUE JUN 18 2013
...SEVERE WEATHER LIKELY THIS AFTERNOON ESPECIALLY NORTHERN EL PASO
COUNTY...
CURRENTLY...
AN MESOSCALE CONVECTIVE VORTICITY CENTER WAS CLEARLY SEEN IS RADAR
IMAGERY SPINNING JUST NE OF THE FAR NE CO BORDER EARLY THIS MORNING
(3 AM). CONVECTIVE OUTFLOW WITH THIS WAS DROPPING SWD ACROSS EC CO.
OTHER CONVECTIVE COMPLEXES WERE NOTED OVER NE NM. A FE LIGHT SHOWERS
WERE NOTED ALONG THE I-25 CORRIDOR AND THE SE PLAINS. DWPTS OVER THE
REGION WERE GENERALLY IN THE 50S OVER THE PLAINS...WITH 30S AND 40S
ELSEWHERE.
TODAY...
I SEE PRETTY STRONG SIGNALS IN THE GUIDANCE TODAY INDICATING THAT WE
MAY SEE A RATHER IMPRESSIVE ROTATING STORM FORM ON THE PALMER DIVIDE
IN THE GENERAL AREA OF DOUGLAS/ELBERT/EL PASO COUNTY AND MOVE
SOUTHEAST ACROSS NE EL PASO COUNTY...INTO LINCOLN COUNTY AND THEN
THE GREATER LA JUNTA REGION LATER IN THE EVENING. THE
NAM...GFS...AND RAP ALL SHOW THIS SAME GENERAL SIGNAL. ALTHOUGH
LARGE SCALE KINEMATICS ARE NOT ALL THAT IMPRESSIVE...SIMULATIONS
SHOW LOCAL BACKING OF THE LLVL WINDS OVER THE PALMER DVD LATE THIS
AFTERNOON...AND THIS LOCAL BACKING OF THE WINDS WILL ENHANCE THE
LLVL SHEAR. RATHER STRONG SE SFC INFLOW IS PRGD (AND MODELS HAVE
BEEN SHOWING THIS FOR DAYS) SO EXPECT STORM WILL BE INFLOW-DOMINANT
FOR A GOOD PART OF ITS LIFE. THE HODOGRAPH IS CURVED BUT THE OVERALL
MAGNITUDE IS NOT STRONG. CAPE IS PROJECTED TO BE ABOUT 1000-1500
J/KG AND TEMPS AT 500 ARE AROUND -9 TO -10C.
WITH THAT SAID...THE HI-RES DATA (SPC SSEO...NSSL WRF...LOCAL
WRF...IS NOT AS AGGRESSIVE AS THE OTHER GUIDANCE. THEY DO SHOW A WEAK
ROTATING STORM THIS REGION BUT MOVE IT OFF QUICKLY TO THE
EAST-SOUTHEAST.
GIVEN THE TIME OF THE YEAR...PAST HISTORY THE LAST COUPLE OF
DAYS...A WEAK SHORT WAVE MOVING ACROSS DURING PRIME HEATING...THE
LEFT FRONT QUAD OF THE SUBTROPICAL JET OVER EC CO...AND THE FACT
THIS WILL BE THE LAST DAY OF STRONGER CONVECTION OVER THE REGION...I
DO BELIEVE WE WILL SEE SOME SEVERE STORMS OVER THE REGION. I HAVE
MENTIONED SEVERE IN THE GRIDDS AND SPC HAS THE AREA OUTLOOKED FOR
TODAY. BASED ON WHAT I HAVE SEEN...THE MOST ORGANIZED SEVERE SHOULD
BE IN THE N EL PASO COUNTY REGION...AS THERE IS THE POSSIBILITY OF
SIGNIFICANT SEVERE HAIL...DAMAGING WINDS AND A LOW SUPERCELL TORNADO
THREAT THIS REGION. I BELIEVE THERE WILL PRIMARILY BE A WIND THREAT
AND MARGINAL SEVERE HAIL THREAT FARTHER SOUTHEAST OVER THE GREATER
LA JUNTA REGION LATER THIS EVENING.
THERE WILL ALSO BE A SLIGHT CHANCE OF SOME LOCALLY HEAVY RAIN OVER
THE WALDO...WHICH MAY CAUSE FLASH FLOODING. GIVEN THE DWPTS...AND
THE FACT THAT STORMS SHOULD BE MOVING...A FLASH FLOOD WATCH IS NOT
WARRANTED AT THIS TIME.
A LOT OF PEOPLE WILL BE EXPOSED ACROSS NORTHERN EL PASO COUNTY LATER
THIS AFTERNOON ASSOCIATED WITH THE BLACK FOREST FIRE MOP-UP
OPERATIONS. LIGHTNING AND LARGE HAIL...WITH THE POSSIBILITY OF FLASH
FLOODING...AND THE VERY SLIGHT CHANCE OF A TORNADO...COULD AFFECT
THESE FOLKS LATER THIS AFTERNOON AND EARLY EVENING.
TONIGHT...
CONVECTION WILL LAST INTO THE EVENING HOURS...WITH MOST IF NOT ALL
OF THE ACTIVITY OUT OF THE REGION BY MIDNIGHT. MUCH DRIER AND WARMER
AIR ALOFT WILL BE MOVING IN LATE TONIGHT.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 342 AM MDT TUE JUN 18 2013
...DANGEROUS FIRE WEATHER CONDITIONS THROUGH THE EXTENDED...
MODELS IN GOOD AGREEMENT THROUGH THE WEEKEND WITH A SLOW MOVING
UPPER LOW OVER THE PACIFIC NORTHWEST AND RIDGE ACROSS THE CENTRAL
CONUS. THIS WILL PUT THE ROCKIES UNDER BROAD SOUTHWESTERLY FLOW
LEADING TO DANGEROUS FIRE WEATHER CONDITIONS ACROSS THE REGION.
WEDNESDAY...STRONG SOUTHWESTERLY FLOW WILL PUSH INTO THE ROCKIES
BY WEDNESDAY MORNING AND SPREAD ACROSS THE EASTERN PLAINS THROUGH
THE AFTERNOON. STRONG MIXING WILL HELP WARM TEMPERATURES INTO THE
MID TO UPPER 90S FOR MUCH OF THE LOWER ELEVATIONS ALONG WITH
DROPPING HUMIDITY VALUES TO LESS THAN 10 PERCENT. WIDESPREAD
SOUTHWEST SURFACE WINDS IN EXCESS OF 20 KTS ARE LIKELY WHICH WILL
LEAD TO THE DANGEROUS FIRE WEATHER CONDITIONS. THE MAIN AREAS OF
CONCERN ARE THE MOUNTAIN AREAS...SAN LUIS VALLEY AND I-25
CORRIDOR. HAVE UPGRADED THE FIRE WEATHER WATCH TO A RED FLAG
WARNING FOR WEDNESDAY AFTERNOON INTO THE EVENING. CRITERIA ARE
BEING MET ACROSS THE PLAINS...BUT FUELS HAVE BEEN LISTED AS NOT
CRITICAL AND AREAS OUT EAST NEAR THE KANSAS BORDER HAVE SEEN
ABUNDANT RAINFALL...SO HAVE NOT INCLUDED THESE AREAS. ALSO REMOVED
POPS FOR WEDNESDAY AFTERNOON AND EVENING OUT NEAR THE KANSAS
BORDER. THE LATEST RUNS OF THE GFS AND NAM HAVE THE DRYLINE MIXING
WELL OUT INTO KANSAS WITH DRY CONDITIONS ACROSS COLORADO.
THURSDAY AND FRIDAY...THE UPPER LOW OVER THE PACIFIC NORTHWEST
WILL SLOWLY DRIFT EAST WITH THE STRONG SOUTHWESTERLY FLOW
CONTINUING ACROSS COLORADO. CONTINUED VERY DANGEROUS FIRE WEATHER
CONDITIONS WILL PERSIST...ESPECIALLY OVER THE MOUNTAIN AREAS AND
ADJACENT PLAINS WHERE MIXING WILL BE GREATEST AND FUELS MOST
CRITICAL. HAVE ISSUED A FIRE WEATHER WATCH FOR THE MOUNTAINS...SAN
LUIS VALLEY AND EL PASO COUNTY FOR THURSDAY...AND WILL LIKELY NEED
TO DO THE SAME FOR FRIDAY IN THE FUTURE. AFTERNOON HIGH
TEMPERATURES WILL REMAIN HOT WITH UPPER 90S TO LOWER 100S EXPECTED
ACROSS THE PLAINS. NO SHOWER OR THUNDERSTORM ACTIVITY IS EXPECTED.
THE PATTERN BEGINS TO SHIFT THIS WEEKEND WITH THE UPPER LOW
LIFTING NORTHEAST INTO SOUTH CENTRAL CANADA. SOUTHWESTERLY FLOW
WILL CONTINUE...HOWEVER MOISTURE WILL BEGIN TO DRAW NORTHWARD INTO
THE FAR SOUTHEASTERN PLAINS. THERE WILL BE A CONTINUED FIRE
WEATHER THREAT OVER THE MOUNTAINS AND SAN LUIS VALLEY THROUGH THE
WEEKEND INTO EARLY NEXT WEEK. THE GFS AND ECMWF BOTH DEVELOP DAILY
THUNDERSTORMS OVER NORTHERN NEW MEXICO AND LIFT THEM NORTHEAST
INTO THE FAR SOUTHEASTERN PLAINS. HAVE LOW POPS GENERALLY ALONG
THE NEW MEXICO BORDER THROUGH THE WEEKEND AS THE THUNDERSTORMS
MOVE INTO THE CENTRAL PLAINS AND CLIP OUR FAR SOUTHEAST ZONES.
TEMPERATURES WILL REMAIN WARM WITH 90S ACROSS THE LOWER ELEVATIONS
INTO EARLY NEXT WEEK. MOZLEY
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z WEDNESDAY MORNING)
ISSUED AT 342 AM MDT TUE JUN 18 2013
STRONG TO SEVERE STORMS WILL BE POSSIBLE LATE THIS AFTERNOON OVER
KCOS. STRONG WINDS AND HAIL WILL BE A THREAT. STRONG OUTFLOW IS NEAR
CERTAIN AT SOME TIME LATE THIS AFTERNOON OR VERY EARLY EVENING.
SURFACE WINDS WILL BE A BIT STRONGER OUT OF THE SOUTH-SOUTHEAST AT
KCOS THIS AFTERNOON BEFORE THE STORMS/OUTFLOW AFFECT THE TAF SITE.
VFR AT KCOS IS EXPECTED LATER THIS EVENING THROUGH TONIGHT.
KPUB WILL ALSO HAVE A SLIGHT CHANCE OF STRONG STORMS LATE THIS
AFTERNOON AND EARLY EVENING. OUTFLOW WINDS ARE ALSO CERTAIN DURING
THIS PERIOD.
KALS SHOULD BE VFR ALL DAY. I CANNOT RULE OUT SOME LOCAL HIGH BASED
CONVECTION CAUSING GUST WINDS AT TIMES DURING THE AFTERNOON.
&&
.PUB WATCHES/WARNINGS/ADVISORIES...
RED FLAG WARNING FROM 11 AM TO 8 PM MDT WEDNESDAY FOR COZ220>227.
FIRE WEATHER WATCH FROM THURSDAY MORNING THROUGH THURSDAY
EVENING FOR COZ220>227.
&&
$$
SHORT TERM...HODANISH
LONG TERM...MOZLEY
AVIATION...HODANISH
AREA FORECAST DISCUSSION
NWS MIAMI FL
803 PM EDT WED JUN 19 2013
.UPDATE...
SHOWERS AND THUNDERSTORMS WERE BEGINNING TO DIMINISH ACROSS SOUTH
FLORIDA EARLY THIS EVENING. AN OUTFLOW BOUNDARY FROM EARLIER
CONVECTION ACROSS THE INTERIOR WAS MOVING SOUTHEAST ACROSS MIAMI-
DADE COUNTY AND SPARKING ISOLATED SHOWERS. THIS ACTIVITY SHOULD
CONTINUE TO WIND DOWN THIS EVENING...WITH PARTLY CLOUDY SKIES AND
WARM TEMPERATURES OVERNIGHT. HAZY SKIES ARE POSSIBLE ON THURSDAY
AS SAHARAN DUST CONTINUES TO MOVE ACROSS SOUTH FLORIDA. ONLY
CHANGES TO THE FORECAST THIS EVENING WERE TO REMOVE POPS AFTER
MIDNIGHT...AND LOWERED TEMPERATURES A COUPLE DEGREES ACROSS THE
INTERIOR.
&&
.PREV DISCUSSION... /ISSUED 730 PM EDT WED JUN 19 2013/
AVIATION...
THE INTERIOR SHOWERS AND THUNDERSTORMS HAVE MOSTLY DISSIPATED
EARLY THIS EVENING...EXCEPT FOR SOME LIGHT TO MODERATE RAINS OVER
THE WESTERN INTERIOR AREAS AND ISOLATED SHOWERS OVER THE EASTERN
INTERIOR AREAS. THESE SHOWERS OVER THE EASTERN INTERIOR AREAS
COULD MOVE EAST INTO THE EAST COAST TAF SITES BEFORE DISSIPATING
THIS EVENING. SO WILL LEAVE A VCSH IN FOR THE EAST COAST TAF SITES
UNTIL 03Z TONIGHT BEFORE GOING DRY FOR REST OF THE NIGHT. KAPF TAF
SITE SHOULD REMAIN DRY FOR TONIGHT.
THE WEATHER ON THURSDAY SHOULD REMAIN DRY OVER THE TAF SITES...DUE
TO DRIER AIR WORKING INTO THE AREA ALONG WITH THE SEA BREEZES
DEVELOPING AND PUSHING INLAND.
THE WINDS TONIGHT WILL REMAIN EASTERLY AT ALL OF THE TAF SITES
WITH THE WINDS DECREASING TO 5 KNOTS OR LESS BY 03Z. THE WINDS
WILL THEN REMAIN LESS THAN 5 KNOTS THROUGH 13Z ON
THURSDAY...BEFORE INCREASING TO AROUND 10 KNOTS BY 16Z. THE ONLY
EXCEPTION TO THIS IS FOR KAPF TAF SITE WHERE THE WINDS WILL BECOME
WESTERLY AROUND 15Z ON THURSDAY...DUE TO THE WEST COAST SEA BREEZE
DEVELOPING AND PUSHING EAST.
THE CEILING AND VIS WILL ALSO REMAIN IN THE VFR CONDITIONS TONIGHT
INTO THURSDAY OVER ALL OF THE TAF SITES.
AVIATIION...54/BNB
PREV DISCUSSION... /ISSUED 231 PM EDT WED JUN 19 2013/
SHORT TERM (TONIGHT-FRIDAY NIGHT)...
EARLY AFTERNOON SHOWERS AND THUNDERSTORMS HAVE ALREADY BEGUN TO
INITIATE ACROSS PORTIONS OF THE LOCAL AREA AS THE EAST AND WEST
COAST SEA BREEZES BEGIN TO PENETRATE INLAND. SOME OF THIS ACTIVITY
APPEARS TO HAVE BEEN ENHANCED BY A MID-LEVEL VORT PROGRESSING
EASTWARD FROM LAKE OKEECHOBEE EARLIER...WHICH SHOWED UP WELL ON THE
VISIBLE SATELLITE LOOP. THE LATEST HRRR AND WRF MODEL REFLECTIVITIES
APPEAR TO BE INITIALIZING WELL WITH THE LATEST RADAR TRENDS AND
GENERALLY INDICATE THIS EARLY AFTERNOON ACTIVITY CONTINUING TO
DEVELOP AND BECOMING CONCENTRATED ACROSS THE INTERIOR AND WRN
LOCATIONS THROUGH THE LATE AFTERNOON AND EARLY EVENING PERIODS AS
THE SEA BREEZES BOUNDARIES PENETRATE FARTHER INLAND AND MERGE.
ALTHOUGH MID-LEVEL LAPSE RATES AND H5 TEMPERATURES ARE NOT VERY
IMPRESSIVE TODAY...A FEW STORMS MAY BECOME STRONG WITH THE MAIN
THREAT BEING GUSTY WINDS UP TO 45 MPH.
TONIGHT THROUGH FRIDAY NIGHT...THE GENERAL TREND WITH ABOVE AVERAGE
TEMPERATURES WILL PERSIST...ESPECIALLY THROUGH THE OVERNIGHT HOURS
WHEN TEMPERATURES ARE FORECAST TO REMAIN SEVERAL DEGREES ABOVE
AVERAGE. AS A RESULT...WARMER MINIMUM TEMPERATURE RECORDS COULD BE
BROKEN EACH NIGHT. MODEL PRECIPITABLE WATER VALUES INDICATE A SLIGHT
DRYING TREND THURSDAY THROUGH FRIDAY AHEAD OF AN APPROACHING
TROPICAL WAVE WITH VALUES TRENDING DOWN TO AROUND 1.5".
HOWEVER...DAYTIME HEATING COMBINED WITH SE LOW-LEVEL FLOW UP TO H7
AROUND THE SUBTROPICAL RIDGE AXIS WILL BE ENOUGH TO SUPPORT ANOTHER
ROUND OF ISLTD/SCT AFTERNOON SHOWERS/TSTMS...ESPECIALLY ACROSS THE
INTERIOR LOCATIONS THROUGH THE LATE AFTERNOON AND EARLY EVENING
PERIODS. HAZY CONDITIONS DUE TO HIGHER CONCENTRATIONS OF DUST
SPREADING INTO THE AREA FROM THE SE WILL REMAIN POSSIBLE EACH
DAY.
LONG TERM (SATURDAY-TUESDAY)...
MODELS REMAIN PERSISTENT FROM RUN TO RUN AND CONTINUE TO INDICATE A
TROPICAL WAVE APPROACHING AND MOVING THROUGH THE AREA OVER THE
WEEKEND. MODEL PWS ASSOCIATED WITH THIS WAVE ARE FORECAST TO NEAR
THE 2" MARK BY SUNDAY...WHICH SHOULD TRANSLATE TO HIGHER RAIN
CHANCES. CONDITIONS SHOULD TREND BACK TO NORMAL THROUGH THE EARLY
HALF OF THE UPCOMING WEEK AS THE WAVE TRACKS WEST AND AWAY FROM THE
LOCAL AREA.
AVIATION...
VFR CONDITIONS WILL PREVAIL THROUGHOUT THE FORECAST PERIOD. WINDS
WILL REMAIN OUT OF THE EAST SOUTHEAST BETWEEN 10 TO 15 KNOTS THIS
AFTERNOON AND THIS EVENING ACROSS THE EAST COAST TERMINALS.
SCATTERED SHOWERS AND THUNDERSTORMS WILL CONTINUE TO DEVELOP THIS
AFTERNOON MAINLY WEST OF THE EAST COAST TERMINALS. AT KAPF, A WEST
COAST SEA BREEZE WILL DEVELOP LATER THIS AFTERNOON. WINDS WILL
DIMINISH ACROSS ALL TERMINALS THIS EVENING AND THEN THEY WILL
INCREASE AGAIN BY THE MIDDLE OF THURSDAY MORNING.
MARINE...
LIGHT TO MODERATE SOUTHEAST WINDS ASSOCIATED WITH HIGH PRESSURE WILL
PERSIST THROUGH 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 20
FORT LAUDERDALE 80 89 81 89 / 20 20 20 20
MIAMI 78 89 80 89 / 20 20 20 20
NAPLES 75 92 74 93 / 20 30 20 30
&&
.MFL WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
AM...NONE.
GM...NONE.
&&
$$
DISCUSSION/MARINE/FIRE...84/AK
AVIATION/RADAR...54/BNB
AREA FORECAST DISCUSSION...UPDATED
NWS MIAMI FL
730 PM EDT WED JUN 19 2013
.AVIATION...
THE INTERIOR SHOWERS AND THUNDERSTORMS HAVE MOSTLY DISSIPATED
EARLY THIS EVENING...EXCEPT FOR SOME LIGHT TO MODERATE RAINS OVER
THE WESTERN INTERIOR AREAS AND ISOLATED SHOWERS OVER THE EASTERN
INTERIOR AREAS. THESE SHOWERS OVER THE EASTERN INTERIOR AREAS
COULD MOVE EAST INTO THE EAST COAST TAF SITES BEFORE DISSIPATING
THIS EVENING. SO WILL LEAVE A VCSH IN FOR THE EAST COAST TAF SITES
UNTIL 03Z TONIGHT BEFORE GOING DRY FOR REST OF THE NIGHT. KAPF TAF
SITE SHOULD REMAIN DRY FOR TONIGHT.
THE WEATHER ON THURSDAY SHOULD REMAIN DRY OVER THE TAF SITES...DUE
TO DRIER AIR WORKING INTO THE AREA ALONG WITH THE SEA BREEZES
DEVELOPING AND PUSHING INLAND.
THE WINDS TONIGHT WILL REMAIN EASTERLY AT ALL OF THE TAF SITES
WITH THE WINDS DECREASING TO 5 KNOTS OR LESS BY 03Z. THE WINDS
WILL THEN REMAIN LESS THAN 5 KNOTS THROUGH 13Z ON
THURSDAY...BEFORE INCREASING TO AROUND 10 KNOTS BY 16Z. THE ONLY
EXCEPTION TO THIS IS FOR KAPF TAF SITE WHERE THE WINDS WILL BECOME
WESTERLY AROUND 15Z ON THURSDAY...DUE TO THE WEST COAST SEA BREEZE
DEVELOPING AND PUSHING EAST.
THE CEILING AND VIS WILL ALSO REMAIN IN THE VFR CONDITIONS TONIGHT
INTO THURSDAY OVER ALL OF THE TAF SITES.
&&
.AVIATIION...54/BNB
.PREV DISCUSSION... /ISSUED 231 PM EDT WED JUN 19 2013/
SHORT TERM (TONIGHT-FRIDAY NIGHT)...
EARLY AFTERNOON SHOWERS AND THUNDERSTORMS HAVE ALREADY BEGUN TO
INITIATE ACROSS PORTIONS OF THE LOCAL AREA AS THE EAST AND WEST
COAST SEA BREEZES BEGIN TO PENETRATE INLAND. SOME OF THIS ACTIVITY
APPEARS TO HAVE BEEN ENHANCED BY A MID-LEVEL VORT PROGRESSING
EASTWARD FROM LAKE OKEECHOBEE EARLIER...WHICH SHOWED UP WELL ON THE
VISIBLE SATELLITE LOOP. THE LATEST HRRR AND WRF MODEL REFLECTIVITIES
APPEAR TO BE INITIALIZING WELL WITH THE LATEST RADAR TRENDS AND
GENERALLY INDICATE THIS EARLY AFTERNOON ACTIVITY CONTINUING TO
DEVELOP AND BECOMING CONCENTRATED ACROSS THE INTERIOR AND WRN
LOCATIONS THROUGH THE LATE AFTERNOON AND EARLY EVENING PERIODS AS
THE SEA BREEZES BOUNDARIES PENETRATE FARTHER INLAND AND MERGE.
ALTHOUGH MID-LEVEL LAPSE RATES AND H5 TEMPERATURES ARE NOT VERY
IMPRESSIVE TODAY...A FEW STORMS MAY BECOME STRONG WITH THE MAIN
THREAT BEING GUSTY WINDS UP TO 45 MPH.
TONIGHT THROUGH FRIDAY NIGHT...THE GENERAL TREND WITH ABOVE AVERAGE
TEMPERATURES WILL PERSIST...ESPECIALLY THROUGH THE OVERNIGHT HOURS
WHEN TEMPERATURES ARE FORECAST TO REMAIN SEVERAL DEGREES ABOVE
AVERAGE. AS A RESULT...WARMER MINIMUM TEMPERATURE RECORDS COULD BE
BROKEN EACH NIGHT. MODEL PRECIPITABLE WATER VALUES INDICATE A SLIGHT
DRYING TREND THURSDAY THROUGH FRIDAY AHEAD OF AN APPROACHING
TROPICAL WAVE WITH VALUES TRENDING DOWN TO AROUND 1.5".
HOWEVER...DAYTIME HEATING COMBINED WITH SE LOW-LEVEL FLOW UP TO H7
AROUND THE SUBTROPICAL RIDGE AXIS WILL BE ENOUGH TO SUPPORT ANOTHER
ROUND OF ISLTD/SCT AFTERNOON SHOWERS/TSTMS...ESPECIALLY ACROSS THE
INTERIOR LOCATIONS THROUGH THE LATE AFTERNOON AND EARLY EVENING
PERIODS. HAZY CONDITIONS DUE TO HIGHER CONCENTRATIONS OF DUST
SPREADING INTO THE AREA FROM THE SE WILL REMAIN POSSIBLE EACH
DAY.
LONG TERM (SATURDAY-TUESDAY)...
MODELS REMAIN PERSISTENT FROM RUN TO RUN AND CONTINUE TO INDICATE A
TROPICAL WAVE APPROACHING AND MOVING THROUGH THE AREA OVER THE
WEEKEND. MODEL PWS ASSOCIATED WITH THIS WAVE ARE FORECAST TO NEAR
THE 2" MARK BY SUNDAY...WHICH SHOULD TRANSLATE TO HIGHER RAIN
CHANCES. CONDITIONS SHOULD TREND BACK TO NORMAL THROUGH THE EARLY
HALF OF THE UPCOMING WEEK AS THE WAVE TRACKS WEST AND AWAY FROM THE
LOCAL AREA.
AVIATION...
VFR CONDITIONS WILL PREVAIL THROUGHOUT THE FORECAST PERIOD. WINDS
WILL REMAIN OUT OF THE EAST SOUTHEAST BETWEEN 10 TO 15 KNOTS THIS
AFTERNOON AND THIS EVENING ACROSS THE EAST COAST TERMINALS.
SCATTERED SHOWERS AND THUNDERSTORMS WILL CONTINUE TO DEVELOP THIS
AFTERNOON MAINLY WEST OF THE EAST COAST TERMINALS. AT KAPF, A WEST
COAST SEA BREEZE WILL DEVELOP LATER THIS AFTERNOON. WINDS WILL
DIMINISH ACROSS ALL TERMINALS THIS EVENING AND THEN THEY WILL
INCREASE AGAIN BY THE MIDDLE OF THURSDAY MORNING.
MARINE...
LIGHT TO MODERATE SOUTHEAST WINDS ASSOCIATED WITH HIGH PRESSURE WILL
PERSIST THROUGH 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 20
FORT LAUDERDALE 80 89 81 89 / 20 20 20 20
MIAMI 78 89 80 89 / 20 20 20 20
NAPLES 75 92 74 93 / 20 30 20 30
&&
.MFL WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
AM...NONE.
GM...NONE.
&&
$$
DISCUSSION/MARINE/FIRE...85/AG
AVIATION/RADAR...55/CWC
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
1001 PM CDT WED JUN 19 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 03Z...
* NONE
ZEBIC
//DISCUSSION...UPDATED 00Z...
LARGE HIGH PRESSURE SURFACE AND ALOFT TO DOMINATE THROUGH THURSDAY.
SURFACE WIND TO KEEP EASTERLY COMPONENT
LAND/LAKE BREEZE WIND PATTERN TO LAST THROUGH THURSDAY AS SURFACE
HIGH PRESSURE SHIFTS FURTHER EAST. WIND TO DROP OFF TONIGHT AND
BECOME SOUTHERLY THEN EASTERLY COMPONENT OFF LAKE TO KICK IN DURING
THE AFTERNOON.
LIMITED AVAILABLE MOISTURE TO KEEP PRECIPITATION CHANCES MINIMAL
INTO THURSDAY NIGHT. ZEBIC
//ORD AND MDW CONFIDENCE...UPDATED 03Z...
* HIGH CONFIDENCE ALL ELEMENTS
ZEBIC
//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.
&&
$$
VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
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WWW.TWITTER.COM/NWSCHICAGO
WWW.YOUTUBE.COM/NWSCHICAGO
AREA FORECAST DISCUSSION...UPDATED
NWS CHICAGO/ROMEOVILLE IL
847 PM CDT WED JUN 19 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 00Z...
* NONE
ZEBIC
//DISCUSSION...UPDATED 00Z...
LARGE HIGH PRESSURE SURFACE AND ALOFT TO DOMINATE THROUGH THURSDAY.
SURFACE WIND TO KEEP EASTERLY COMPONENT
LAND/LAKE BREEZE WIND PATTERN TO LAST THROUGH THURSDAY AS SURFACE
HIGH PRESSURE SHIFTS FURTHER EAST. WIND TO DROP OFF TONIGHT AND
BECOME SOUTHERLY THEN EASTERLY COMPONENT OFF LAKE TO KICK IN DURING
THE AFTERNOON.
LIMITED AVAILABLE MOISTURE TO KEEP PRECIPITATION CHANCES MINIMAL
INTO THURSDAY NIGHT. ZEBIC
//ORD AND MDW CONFIDENCE...UPDATED 00Z...
* HIGH CONFIDENCE ALL ELEMENTS
ZEBIC
//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 LINCOLN IL
1219 PM CDT TUE JUN 18 2013
.DISCUSSION...
ISSUED 1010 AM CDT TUE JUN 18 2013
FRONTAL BOUNDARY HAS SETTLED SOUTHWARD TO AROUND THE I-74
CORRIDOR. VIGOROUS SHORTWAVE CURRENTLY IN NORTHEAST IOWA WILL
CONTINUE TO MOVE SOUTHEAST...AND WILL HELP TRIGGER SOME
THUNDERSTORMS OVER CENTRAL ILLINOIS BY MID AFTERNOON. CURRENTLY
HAVE A SLIGHT RISK OF SEVERE WEATHER FROM ABOUT PEORIA TO
WINCHESTER EASTWARD. LATEST RAP MODEL SHOWING ABOUT 40-50 KNOTS OF
0-6KM BULK SHEAR WITH THIS SHORTWAVE...WITH OVER 2000 J/KG OF
SBCAPE...SO THIS RISK AREA APPEARS WARRANTED. COULD SEE SOME
HEAVIER RAINS WITH THE STORMS...ALTHOUGH THE SOUTH HALF OF THE CWA
APPEARS MORE LIKELY FOR ANY SIGNIFICANT RAINS AS PWAT VALUES IN
THAT AREA ARE CLOSE TO 1.5 INCHES BY MID AFTERNOON.
HAVE SENT SOME MINOR ZONE/GRID UPDATES...MAINLY TO ADJUST THE
CLOUD AND WIND TRENDS. HIGH TEMPERATURES STILL APPEAR REASONABLE.
GEELHART
&&
.AVIATION...
ISSUED 1218 PM CDT TUE JUN 18 2013
MAIN CONCERN FOR THIS TAF SET IS TIMING OF CONVECTION THIS
AFTERNOON. SEVERAL HIGH-RESOLUTION MODELS POINTING TO SCATTERED
STORM DEVELOPMENT IN CENTRAL ILLINOIS BEGINNING AROUND 19-20Z AND
MOST NUMEROUS DURING THE MID TO LATE AFTERNOON HOURS. HAVE KEPT
VCTS WORDING AT ALL TAF SITES FOR THIS AFTERNOON...BUT HAVE
FOCUSED ON THE KSPI-KDEC-KCMI CORRIDOR BY ADDING TEMPO PERIODS OF
TSRA AND VARIABLE/GUSTY WINDS WITH THE STORMS...AS THIS AREA IS
NEAR A FRONTAL BOUNDARY. SHOULD SEE THE CONVECTION FADE OUT WITH
SUNSET. DRIER NORTHEAST FLOW WILL CLEAR OUT MUCH OF THE AREA
OVERNIGHT. HAVE HELD OFF ON ANY OVERNIGHT MVFR FOG CONDITIONS...
BUT ANY AREAS THAT GET EXCESSIVE RAINFALL DURING THE DAY MAY SEE
SOME DEVELOP ALTHOUGH CONFIDENCE IS NOT HIGH AT THE MOMENT.
GEELHART
&&
.PREV DISCUSSION...
ISSUED 254 AM CDT TUE JUN 18 2013
SHORT TERM...TODAY THROUGH THURSDAY
07Z/2AM SURFACE ANALYSIS SHOWS A WEAK COLD FRONT EXTENDING FROM
NORTHEAST IOWA E/SE ACROSS NORTH-CENTRAL ILLINOIS. THIS BOUNDARY
WILL BE THE PRIMARY FOCUSING MECHANISM FOR WIDELY SCATTERED
CONVECTION AS IT SAGS SLOWLY SOUTHWARD LATER TODAY. VIGOROUS
SHORT-WAVE TROUGH CURRENTLY NOTED ON WATER VAPOR IMAGERY OVER
SOUTHERN MINNESOTA WILL TRACK SOUTHEASTWARD AS WELL...PROVIDING
ENHANCED LIFT ACROSS THE AREA DURING PEAK HEATING. WITH SURFACE
DEWPOINTS ALONG/SOUTH OF THE BOUNDARY IN THE MIDDLE TO UPPER
60S...CAPE VALUES WILL REACH THE 1500 TO 2500J/KG RANGE. IN
ADDITION...0-6KM SHEAR WILL INCREASE TO AROUND 40KT ON THE SOUTHERN
PERIPHERY OF THE APPROACHING WAVE. ALL THESE INGREDIENTS WILL COME
TOGETHER TO PRODUCE SCATTERED THUNDERSTORMS THIS AFTERNOON...A FEW
OF WHICH COULD PRODUCE GUSTY WINDS AND HAIL. WILL CARRY 30-40 POPS
ACROSS THE ENTIRE AREA ACCORDINGLY. AS DAYTIME INSTABILITY IS
LOST...CONVECTION WILL DISSIPATE AFTER SUNSET. WILL LINGER A
SLIGHT CHANCE POP ACROSS THE S/SW KILX CWA THIS EVENING...THEN
WILL GO DRY ACROSS THE BOARD OVERNIGHT.
SURFACE HIGH PRESSURE BUILDING INTO THE REGION BEHIND THE
DEPARTING FRONT WILL PROVIDE WARM/DRY WEATHER ON WEDNESDAY...WITH
AFTERNOON HIGHS IN THE LOWER 80S AND OVERNIGHT LOWS IN THE LOWER
60S. NEXT APPROACHING UPPER WAVE WILL COME INTO THE PICTURE ON
THURSDAY...AS A PIECE OF ENERGY EJECTS EASTWARD FROM DEEP UPPER
LOW SPINNING OFF THE COAST OF THE PACIFIC NORTHWEST. THIS WAVE IS
PROGGED TO TRACK ACROSS CENTRAL ILLINOIS ON THURSDAY. DESPITE
SYNOPTIC LIFT ASSOCIATED WITH THIS FEATURE...AIR MASS WILL BE
RATHER DRY...SO AM NOT EXPECTING MUCH IN THE WAY OF PRECIP. HAVE
GONE WITH A PARTLY SUNNY FORECAST...WITH JUST A SLIM CHANCE FOR
SHOWERS/THUNDER WEST OF I-55 THURSDAY AFTERNOON.
LONG TERM...FRIDAY THROUGH MONDAY
UPPER RIDGE IS EXPECTED TO BUILD ACROSS THE MIDWEST BY THE END OF
THE WEEK...LEADING TO A HOT AND LARGELY DRY EXTENDED FORECAST.
STILL SOME QUESTION AS TO HOW QUICKLY THE RIDGE WILL BUILD AND
WHETHER ANY NOCTURNAL MCS ACTIVITY WILL IMPACT PARTS OF THE AREA
FRIDAY/SATURDAY...HOWEVER MODEL CONSENSUS CONTINUES TO SUGGEST
MOST OF THIS PRECIP WILL BE FOCUSED FURTHER NORTH ACROSS THE UPPER
MIDWEST INTO THE GREAT LAKES. WILL THEREFORE CONTINUE WITH A
MAINLY DRY FORECAST ACROSS CENTRAL ILLINOIS...WITH JUST SLIGHT
CHANCE POPS ACROSS THE FAR NORTH. MAIN STORY WILL BE THE HEAT...AS
HIGH TEMPS REACH THE 90S OVER THE WEEKEND. NEXT BIG QUESTION WILL
BE HOW QUICKLY THE RIDGE WILL FLATTEN EARLY NEXT WEEK. 00Z JUN 18
GFS/ECMWF ARE IN GOOD AGREEMENT THROUGH 168HR/00Z TUE...THEN
SOLUTIONS DIVERGE BY THE MIDDLE OF NEXT WEEK AS GFS HOLDS ONTO
RIDGING ACROSS THE MIDWEST...WHILE THE ECMWF SHIFTS THE RIDGE
FURTHER WEST INTO THE ROCKIES. BASED ON THE PATTERN WE HAVE BEEN
IN FOR MUCH OF THE SPRING...THINK ECMWF HAS A MORE REALISTIC
ANSWER. WILL THEREFORE GRADUALLY INTRODUCE SHOWERS/THUNDERSTORMS
INTO THE FORECAST ACROSS THE NORTHERN HALF OF THE CWA BY
MONDAY/MONDAY NIGHT...THEN EVERYWHERE TUESDAY AS THE RIDGE WEAKENS
AND A FRONTAL BOUNDARY SAGS SOUTHWARD INTO THE REGION.
BARNES
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS LINCOLN IL
1011 AM CDT TUE JUN 18 2013
.DISCUSSION...
ISSUED 1010 AM CDT TUE JUN 18 2013
FRONTAL BOUNDARY HAS SETTLED SOUTHWARD TO AROUND THE I-74
CORRIDOR. VIGOROUS SHORTWAVE CURRENTLY IN NORTHEAST IOWA WILL
CONTINUE TO MOVE SOUTHEAST...AND WILL HELP TRIGGER SOME
THUNDERSTORMS OVER CENTRAL ILLINOIS BY MID AFTERNOON. CURRENTLY
HAVE A SLIGHT RISK OF SEVERE WEATHER FROM ABOUT PEORIA TO
WINCHESTER EASTWARD. LATEST RAP MODEL SHOWING ABOUT 40-50 KNOTS OF
0-6KM BULK SHEAR WITH THIS SHORTWAVE...WITH OVER 2000 J/KG OF
SBCAPE...SO THIS RISK AREA APPEARS WARRANTED. COULD SEE SOME
HEAVIER RAINS WITH THE STORMS...ALTHOUGH THE SOUTH HALF OF THE CWA
APPEARS MORE LIKELY FOR ANY SIGNIFICANT RAINS AS PWAT VALUES IN
THAT AREA ARE CLOSE TO 1.5 INCHES BY MID AFTERNOON.
HAVE SENT SOME MINOR ZONE/GRID UPDATES...MAINLY TO ADJUST THE
CLOUD AND WIND TRENDS. HIGH TEMPERATURES STILL APPEAR REASONABLE.
GEELHART
&&
.AVIATION...
ISSUED 650 AM CDT TUE JUN 18 2013
LIGHT FOG WITH MVFR VSBYS POSSIBLE OVER CENTRAL IL TAF SITES NEXT
HOUR OR TWO ESPECIALLY AT BMI AND CMI ALONG WITH 500 FOOT BROKEN
CEILINGS BRIEFLY POSSIBLE. OTHERWISE A FRONTAL BOUNDARY PUSHING
SOUTHWARD TOWARD I-74 EARLY THIS MORNING WILL BE THE FOCUS FOR
ISOLATED SHOWERS AND THUNDERSTORMS THIS AFTERNOON AS IT PUSHES
SOUTHWARD ACROSS THE CENTRAL IL TERMINAL AIRPORTS. ALSO A VIGOROUS
SHORT WAVE (572 DM 500 MB LOW) NEAR THE MN/IA BORDER WILL TRACK SE
ACROSS CENTRAL IL THIS AFTERNOON AND PROVIDE ADDITIONAL LIFT WITH
UNSTABLE AIR MASS WITH CAPES OF 1500-2500 J/KG. HI-RES MODELS SHOW
I-74 TAF SITES MAY BE ON NORTHERN EDGE OF THIS CONVECTION DEVELOP
THIS AFTERNOON. HAVE VFR BROKEN CEILINGS AROUND 5K FT THIS
AFTERNOON...THEN SCATTERED OUT EARLY EVENING AND CLEAR BETWEEN
02-04Z THIS EVENING. WSW WINDS AROUND 5 KTS WILL TURN NE AND
INCREASE TO 7-11 KTS DURING THIS MORNING AND HAVE RECENTLY DONE SO
AT BMI AS FRONTAL BOUNDARY EASES SOUTHWARD FROM I-74. NE WINDS TO
DIMINISH LIGHT AFTER SUNSET TONIGHT.
07
&&
.PREV DISCUSSION...
ISSUED 254 AM CDT TUE JUN 18 2013
SHORT TERM...TODAY THROUGH THURSDAY
07Z/2AM SURFACE ANALYSIS SHOWS A WEAK COLD FRONT EXTENDING FROM
NORTHEAST IOWA E/SE ACROSS NORTH-CENTRAL ILLINOIS. THIS BOUNDARY
WILL BE THE PRIMARY FOCUSING MECHANISM FOR WIDELY SCATTERED
CONVECTION AS IT SAGS SLOWLY SOUTHWARD LATER TODAY. VIGOROUS
SHORT-WAVE TROUGH CURRENTLY NOTED ON WATER VAPOR IMAGERY OVER
SOUTHERN MINNESOTA WILL TRACK SOUTHEASTWARD AS WELL...PROVIDING
ENHANCED LIFT ACROSS THE AREA DURING PEAK HEATING. WITH SURFACE
DEWPOINTS ALONG/SOUTH OF THE BOUNDARY IN THE MIDDLE TO UPPER
60S...CAPE VALUES WILL REACH THE 1500 TO 2500J/KG RANGE. IN
ADDITION...0-6KM SHEAR WILL INCREASE TO AROUND 40KT ON THE SOUTHERN
PERIPHERY OF THE APPROACHING WAVE. ALL THESE INGREDIENTS WILL COME
TOGETHER TO PRODUCE SCATTERED THUNDERSTORMS THIS AFTERNOON...A FEW
OF WHICH COULD PRODUCE GUSTY WINDS AND HAIL. WILL CARRY 30-40 POPS
ACROSS THE ENTIRE AREA ACCORDINGLY. AS DAYTIME INSTABILITY IS
LOST...CONVECTION WILL DISSIPATE AFTER SUNSET. WILL LINGER A
SLIGHT CHANCE POP ACROSS THE S/SW KILX CWA THIS EVENING...THEN
WILL GO DRY ACROSS THE BOARD OVERNIGHT.
SURFACE HIGH PRESSURE BUILDING INTO THE REGION BEHIND THE
DEPARTING FRONT WILL PROVIDE WARM/DRY WEATHER ON WEDNESDAY...WITH
AFTERNOON HIGHS IN THE LOWER 80S AND OVERNIGHT LOWS IN THE LOWER
60S. NEXT APPROACHING UPPER WAVE WILL COME INTO THE PICTURE ON
THURSDAY...AS A PIECE OF ENERGY EJECTS EASTWARD FROM DEEP UPPER
LOW SPINNING OFF THE COAST OF THE PACIFIC NORTHWEST. THIS WAVE IS
PROGGED TO TRACK ACROSS CENTRAL ILLINOIS ON THURSDAY. DESPITE
SYNOPTIC LIFT ASSOCIATED WITH THIS FEATURE...AIR MASS WILL BE
RATHER DRY...SO AM NOT EXPECTING MUCH IN THE WAY OF PRECIP. HAVE
GONE WITH A PARTLY SUNNY FORECAST...WITH JUST A SLIM CHANCE FOR
SHOWERS/THUNDER WEST OF I-55 THURSDAY AFTERNOON.
LONG TERM...FRIDAY THROUGH MONDAY
UPPER RIDGE IS EXPECTED TO BUILD ACROSS THE MIDWEST BY THE END OF
THE WEEK...LEADING TO A HOT AND LARGELY DRY EXTENDED FORECAST.
STILL SOME QUESTION AS TO HOW QUICKLY THE RIDGE WILL BUILD AND
WHETHER ANY NOCTURNAL MCS ACTIVITY WILL IMPACT PARTS OF THE AREA
FRIDAY/SATURDAY...HOWEVER MODEL CONSENSUS CONTINUES TO SUGGEST
MOST OF THIS PRECIP WILL BE FOCUSED FURTHER NORTH ACROSS THE UPPER
MIDWEST INTO THE GREAT LAKES. WILL THEREFORE CONTINUE WITH A
MAINLY DRY FORECAST ACROSS CENTRAL ILLINOIS...WITH JUST SLIGHT
CHANCE POPS ACROSS THE FAR NORTH. MAIN STORY WILL BE THE HEAT...AS
HIGH TEMPS REACH THE 90S OVER THE WEEKEND. NEXT BIG QUESTION WILL
BE HOW QUICKLY THE RIDGE WILL FLATTEN EARLY NEXT WEEK. 00Z JUN 18
GFS/ECMWF ARE IN GOOD AGREEMENT THROUGH 168HR/00Z TUE...THEN
SOLUTIONS DIVERGE BY THE MIDDLE OF NEXT WEEK AS GFS HOLDS ONTO
RIDGING ACROSS THE MIDWEST...WHILE THE ECMWF SHIFTS THE RIDGE
FURTHER WEST INTO THE ROCKIES. BASED ON THE PATTERN WE HAVE BEEN
IN FOR MUCH OF THE SPRING...THINK ECMWF HAS A MORE REALISTIC
ANSWER. WILL THEREFORE GRADUALLY INTRODUCE SHOWERS/THUNDERSTORMS
INTO THE FORECAST ACROSS THE NORTHERN HALF OF THE CWA BY
MONDAY/MONDAY NIGHT...THEN EVERYWHERE TUESDAY AS THE RIDGE WEAKENS
AND A FRONTAL BOUNDARY SAGS SOUTHWARD INTO THE REGION.
BARNES
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS DES MOINES IA
937 PM CDT WED JUN 19 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...20/00Z
ISSUED AT 644 PM CDT WED JUN 19 2013
VFR CONDITIONS STATEWIDE AT 00Z EVEN THOUGH THERE ARE PATCHES OF
BKN/OVC CU AND MID/HIGH CLOUDS. ISOLATED THUNDERSTORMS NEAR KFSD
ARE NOT EXPECTED TO AFFECT TAF SITES. CLOUDS SHOULD SHOW TYPICAL
DIURNAL DISSIPATION INTO THE EVENING. ALTHOUGH DEWPOINTS CONTINUE
TO INCREASE FEEL SE WINDS SHOULD STAY UP ENOUGH TO PRECLUDE MVFR
FOG FROM DEVELOPING. SE WINDS WILL INCREASE FURTHER BY MIDDAY AND
MODELS AND ENSEMBLES SHOW BEST CHANCES OF CONVECTION NORTH AND
WEST. VCSH HAS BEEN ADDED IN THE AFTERNOON AT KFOD/KDSM/KMCW FOR A START.
&&
.DMX WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
UPDATE...SMALL
SHORT TERM...PODRAZIK
LONG TERM...DONAVON
AVIATION...SMALL
AREA FORECAST DISCUSSION
NWS DES MOINES IA
645 PM CDT WED JUN 19 2013
.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...20/00Z
ISSUED AT 644 PM CDT WED JUN 19 2013
VFR CONDITIONS STATEWIDE AT 00Z EVEN THOUGH THERE ARE PATCHES OF
BKN/OVC CU AND MID/HIGH CLOUDS. ISOLATED THUNDERSTORMS NEAR KFSD
ARE NOT EXPECTED TO AFFECT TAF SITES. CLOUDS SHOULD SHOW TYPICAL
DIURNAL DISSIPATION INTO THE EVENING. ALTHOUGH DEWPOINTS CONTINUE
TO INCREASE FEEL SE WINDS SHOULD STAY UP ENOUGH TO PRECLUDE MVFR
FOG FROM DEVELOPING. SE WINDS WILL INCREASE FURTHER BY MIDDAY AND
MODELS AND ENSEMBLES SHOW BEST CHANCES OF CONVECTION NORTH AND
WEST. VCSH HAS BEEN ADDED IN THE AFTERNOON AT KFOD/KDSM/KMCW FOR A START.
&&
.DMX WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
SHORT TERM...PODRAZIK
LONG TERM...DONAVON
AVIATION...SMALL
AREA FORECAST DISCUSSION
NWS WICHITA KS
723 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 00Z TAFS THROUGH 00Z THURSDAY EVENING)
ISSUED AT 655 PM CDT WED JUN 19 2013
BREEZY SOUTHEAST WINDS WILL RELAX ACROSS SOUTHEAST KANSAS THIS
EVENING WHILE PICKING UP BY TOMORROW AFTERNOON ACROSS THE AREA.
SPEEDS MAY APPROACH ADVISORY CRITERIA AT TIMES AFTER 20-21Z.
WIDELY SCATTERED THUNDERSTORMS WILL DEVELOP AFTER 07-09Z ALONG AND
WEST OF I-135 AND DRIFT EASTWARD THROUGH THE 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 TOPEKA KS
619 PM CDT WED JUN 19 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 00Z TAFS THROUGH 00Z THURSDAY EVENING)
ISSUED AT 616 PM CDT WED JUN 19 2013
VFR CONDITIONS ARE FORECAST THROUGH THE ENTIRE TAF PERIOD. THE
MAIN UNCERTAINTY LIES IN THE TIMING OF SCATTERED TS DEVELOPMENT.
CURRENT INDICATIONS SUGGEST THAT TS WILL HOLD OFF UNTIL AFTER 12Z
AT TAF SITES...ALTHOUGH THERE IS SMALL POTENTIAL FOR DEVELOPMENT
PRIOR TO 12Z. IT CURRENTLY APPEARS THAT BEST TS CHANCES ARE
BETWEEN 13 AND 18Z...BUT SCATTERED STORMS COULD PERSIST THROUGH
THE AFTERNOON. SOUTH WINDS WILL ALSO BE GUSTY AFTER 15Z WITH A FEW
GUSTS UP TO 25 KTS.
&&
.TOP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...WOLTERS
LONG TERM...BYRNE
AVIATION...BARJENBRUCH
AREA FORECAST DISCUSSION
NWS GOODLAND KS
1155 AM MDT TUE JUN 18 2013
.SHORT TERM...(TODAY THROUGH THURSDAY NIGHT)
ISSUED AT 358 AM MDT TUE JUN 18 2013
FORECAST PROBLEMS WILL BE THUNDERSTORM CHANCES AND HOW HOT DOES IT
GET. SATELLITE CONTINUING TO SHOW AN AMPLIFIED AND BLOCKY PATTERN
OVER THE CENTRAL/EASTERN PACIFIC INTO WESTERN NORTH AMERICA. SUBTLE
SHORTWAVE TROUGHS MOVING THROUGH THE FLOW WITH THE STRONGEST
SHORTWAVE TROUGHS FURTHER NORTH AND EAST. AIR MASS HAS DRIED
SIGNIFICANTLY OVER THE LAST 24 HOURS. MODELS AND FORECAST FAILED FROM
YESTERDAY. MID LEVEL RIDGING ENDED UP BEING STRONGER OVER THE AREA
WITH THE FRONT WELL SOUTH OF THE REGION.
AT JET LEVEL APPEARED TO INITIALIZE FINE. MODELS WERE NOT TOO FAR
APART AT MID LEVELS. THE CANADIAN AND GFS WERE DOING THE BEST WITH
THE OLDER ECMWF DOING THE WORST. THE HRRR WAS CATCHING THE INCOMING
THUNDERSTORM OUTFLOW WINDS/CLUSTER WELL AND WILL USE INITIALLY.
OUTSIDE OF THE POSSIBLE MESOSCALE AFFECTS OF THUNDERSTORM CLUSTER
MOVING IN...THE ECMWF WAS DOING THE BEST ON THE SURFACE WIND AND
PRESSURE FIELD. THE NAM...GFS AND UKMET WERE DOING THE BEST ON THE
LOW LEVEL THERMAL FIELD.
TODAY/TONIGHT...WILL BE MONITORING CONVECTIVE COMPLEX FOR AS LONG AS
POSSIBLE. THE BEHAVIOR OF THIS SYSTEM COULD HAVE SIGNIFICANT
IMPACTS ON THE FORECAST FOR THE REST OF THE DAY. FOR NOW USED THE
HRRR FOR THE POPS AND WINDS THIS MORNING SINCE IT IS CATCHING THIS
CLUSTER OF STORMS WELL.
MAIN JET LIFT REMAINS SOUTH OF THE AREA THROUGH THE DAY. MAIN AREA
OF SURFACE CONVERGENCE LIES WEST OF THE AREA WITH A SHORTWAVE TROUGH
APPROACHING THE WESTERN PORTION OF THE AREA LATE IN THE DAY. SO WILL
KEEP THE HIGHEST POPS OUT IN THE FAR WEST IN THE AFTERNOON. NOT SURE
IF TEMPERATURES WILL BE AFFECTED BY MORNING THUNDERSTORMS. AT THIS
TIME AM THINKING THEY WILL NOT BE AFFECTED TOO MUCH. SO WENT NEAR
TO JUST BELOW GUIDANCE.
QUESTIONS THEN BECOMES HOW FAR EAST THUNDERSTORMS WILL MAKE IT INTO
THE FORECAST AREA DURING THE NIGHT. AFTER 06Z MODELS SHOW A WEAK LEFT
FRONT QUADRANT AFFECTING THE SOUTHERN THIRD TO HALF OF THE AREA.
SHORTWAVE TROUGH MAKES A LITTLE PROGRESS TOWARD THE EAST WITH THE
INSTABILITY AXIS MAKING OVER THE EASTERN END OF THE AREA BY THE END
OF THE NIGHT. STORM MOTIONS ARE SOUTH TO SOUTHWEST. ELEVATED CINH
IS THE LOWEST AND BREAKABLE IN THE EAST BY THE END OF THE NIGHT. SO
WILL TRANSITION THE CHANCE POPS TOWARD THE EAST WHILE KEEPING SOME
KIND OF CHANCE IN THE WEST DUE TO THE PROXIMITY OF THE MID AND
UPPER LIFT REMAINS IN PLACE.
WEDNESDAY/WEDNESDAY NIGHT...SOME JET LIFT REMAINS NEAR THE SOUTHERN
PORTION OF THE AREA IN THE MORNING. BUT THEN THE JET GRADUALLY MOVES
SOUTH THE REST OF THE DAY AND LOOKS TO BE WELL SOUTH BY THE END OF
THE DAY. LINGERING LIFT FROM EXITING SHORTWAVE SHOULD ALLOW FOR A
SLIGHT CHANCE OF THUNDERSTORMS IN THE EAST IN THE MORNING.
THEN THE QUESTION IS WHERE DOES THE REDEVELOPMENT OCCUR IN THE
AFTERNOON. NEXT SHORTWAVE SHOULD BE JUST WEST OF THE COLORADO
BORDER BY LATE IN THE AFTERNOON WITH THE INSTABILITY AXIS JUST TO
THE EAST OF THAT. SO WILL START WITH A SLIGHT CHANCE NEAR THE BORDER
AND HAVE A LOW CHANCE IN THE EASTERN PORTION. THEN THIS SHOULD
PROGRESS TOWARD THE EAST FOR THE REST OF THE NIGHT.
MODELS DIFFER ON THE DEGREE THEY INCREASE THE WINDS. IT DEFINITELY
LOOKS LIKE IT WILL BE WINDY AND POSSIBLY CLOSE TO ADVISORY
CRITERIA. ALSO DEWPOINTS LOOK LIKE THEY BECOME LOW IN THE FAR WEST
WHERE COMBINED WITH THE STRONG WINDS COULD CAUSE FIRE WEATHER
ISSUES. MODELS WARMER THAN 24 HOURS AGO AND YESTERDAYS FORECAST.
CONSIDERING WILL NOT HAVE MUCH IF ANY DOWNSLOPE COMPONENT...AM
SKEPTICAL OF TOO BIG OF AN INCREASE.
THURSDAY/THURSDAY NIGHT...MODELS SHOW A BOUNDARY MOVE INTO THE AREA
AND THEN STALLING OR WAFFLING BACK AND FORTH. INITIALLY FOR THE DAY
ON THURSDAY...THERE DOES NOT APPEAR TO BE A LOT OF COOLING BEHIND
THIS BOUNDARY WITH VERY TOASTY MID LEVEL TEMPERATURES. ALSO
SOUNDINGS SHOW A DEEP DRY LAYER. SHORTWAVE TROUGH IS ALSO EXPECTED
TO MOVE THROUGH...MAINLY ACROSS THE NORTHWEST HALF. BY THE END OF THE
DAY THE LEFT FRONT QUADRANT LOOKS TO BE AFFECTING THE SOUTHEAST THIRD
OR JUST SOUTH OF THE AREA. DURING THE NIGHT THIS LIFT LOOKS TO REMAIN
NEAR TO THE SOUTHERN PORTION OF THE FORECAST AREA. SO DESPITE SOME
FAVORABLE PARAMETERS...WILL KEEP THIS WHOLE PERIOD DRY DUE TO THE MID
LEVEL TEMPERATURES AND VERY DEEP DRY LAYER.
MODELS CONTINUE THEIR WARMING TREND DESPITE THE PRESENCE OF A WIND
SHIFT. THE NORTHERN PORTION LOOKS TO BE THE MOST AFFECTED BY THE
BOUNDARY BUT NOT A WHOLE LOT. IT WILL DEFINITELY BE IN THE MIDDLE
90S THERE. GIVEN THE 850 MB TEMPERATURES IT WILL GET NEAR TO A
LITTLE ABOVE 100 DEGREES. TEMPERATURES MAY NEED TO BE RAISED EVEN
MORE.
.LONG TERM...(FRIDAY THROUGH MONDAY)
ISSUED AT 211 AM MDT TUE JUN 18 2013
LONG RANGE MODELS IN GENERAL AGREEMENT WITH UPPER LEVEL LOW PRESSURE
SYSTEM OVER THE PACIFIC NORTHWEST...WITH A TROUGH PATTERN OVER THE
WESTERN THIRD OF THE CONUS. RIDGE OVER THE SOUTHEAST REGION CREATES
MERIDIONAL FLOW PATTERN OVER THE CENTRAL PLAINS. AREAS OF STRONGEST
500 MB JET SHOULD REMAIN IN THE NORTHERN PLAINS. EMBEDDED
SHORTWAVES BEGIN TO MOVE THROUGH THE TRI STATE AREA FRIDAY EVENING.
UPPER LEVEL SHORTWAVE AND STRONGER LOWER LEVEL JET SHOULD AID IN
DEEPENING OF SURFACE LOW PRESSURE. DRY LINE AT THE SURFACE LOOKS
TO HAVE A STRONG GRADIENT OF APPROXIMATELY 30 DEGREES ACROSS WESTERN
KANSAS...WHICH COULD PROVIDE SOME SURFACE LIFT FOR AFTERNOON AND
EVENING CONVECTIVE DEVELOPMENT. HOWEVER, MODELS INDICATE THE DRY
LINE WILL BE STATIONARY AROUND THE CO/KS BORDER...WHICH WOULD NOT
INITIATE CONVECTION. CAPE/LI/AND K INDEX PARAMETERS ARE MOST
SUPPORTIVE OF CONVECTION TOWARDS CENTRAL KANSAS...WITH MARGINAL
VALUES AT BEST FOR THE TRI STATE AREA. DRY LINE LOOKS TO PROGRESS
MORE EASTWARD FOR SATURDAY AND SUNDAY...WITH INSTABILITY PARAMETERS
BECOMING MORE FAVORABLE FOR AFTERNOON CONVECTIVE DEVELOPMENT.
STRONG SOUTHERLY FLOW WITH WARM AIR ADVECTION WILL KEEP SURFACE
TEMPERATURES WARM THROUGHOUT THE EXTENDED FORECAST PERIOD...WITH
HIGH TEMPERATURES IN THE UPPER 80S TO MID 90S. STRONG PRESSURE
GRADIENT ACROSS THE SOUTHERN PLAINS WILL KEEP WIND SPEEDS BETWEEN 20
AND 30 MPH WITH HIGHER GUSTS THROUGHOUT THE AREA FOR THE WEEKEND.
850 MB LEVEL SHOWS GOOD SOUTHWEST FLOW WITH PLENTY OF WARM AIR
ADVECTION FOR MONDAY...WITH TEMPERATURES AROUND 33 C. SURFACE
TEMPERATURES SHOULD BE WARM AS WELL LOOK TO BE IN THE UPPER 90S FOR
MONDAY WITH DRIER AIR ACROSS THE REGION WITH SOUTH WINDS SHIFT TO
SOUTHWEST. SOME LOCATIONS COULD SEE TRIPLE DIGITS FOR HIGH
TEMPERATURES.
THE MAIN STORY FOR THE PERIOD IS THE RETURN OF WARM TEMPERATURES TO
THE AREA. THE BEST CHANCES FOR PRECIPITATION WOULD BE SUNDAY
AFTERNOON...BUT CHANCES FOR RAIN SHOWERS AND THUNDERSTORMS EXIST
SATURDAY AFTERNOON THROUGH MONDAY AFTERNOON. AN UPPER LEVEL RIDGE
LOOKS TO BUILD INTO THE REGION FOR TUESDAY...LOOKING TO PROVIDE
FAIR WEATHER FOR THE MIDDLE OF NEXT WEEK WITH A CONTINUATION OF
WARM TEMPERATURES.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY)
ISSUED AT 1155 AM MDT TUE JUN 18 2013
AFTERNOON CUMULUS WILL GRADUALLY DEVELOP THIS AFTERNOON WITH BASES
AROUND FL060. SURFACE WINDS WILL BE SSE AT 10-15 WITH SOME HIGHER
GUSTS AT KGLD THIS AFTERNOON. SPECIFIC THUNDERSTORM LOCATIONS STILL
A BIT UNCERTAIN FOR LATER THIS AFTERNOON INTO EVENING. BETTER
POTENTIAL AT KGLD THAN KMCK BUT FOR NOW HAVE INCLUDED VCTS AT BOTH
TERMINALS ROUGHLY IN THE 00Z-03Z TIMEFRAME. CEILINGS WILL REMAIN VFR
THROUGH THE PERIOD AT BOTH TERMINALS EVEN WITH CONVECTION. SURFACE
WINDS WILL STRENGTHEN AND BECOME GUSTY ON WEDNESDAY AT BOTH
TERMINALS BUT ESPECIALLY KGLD WHERE GUSTS OF 25-30 KTS WILL BE
POSSIBLE BY LATE MORNING WEDNESDAY.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
SHORT TERM...BULLER
LONG TERM...MK
AVIATION...DLF
AREA FORECAST DISCUSSION
NWS GOODLAND KS
531 AM MDT TUE JUN 18 2013
.SHORT TERM...(TODAY THROUGH THURSDAY NIGHT)
ISSUED AT 358 AM MDT TUE JUN 18 2013
FORECAST PROBLEMS WILL BE THUNDERSTORM CHANCES AND HOW HOT DOES IT
GET. SATELLITE CONTINUING TO SHOW AN AMPLIFIED AND BLOCKY PATTERN
OVER THE CENTRAL/EASTERN PACIFIC INTO WESTERN NORTH AMERICA. SUBTLE
SHORTWAVE TROUGHS MOVING THROUGH THE FLOW WITH THE STRONGEST
SHORTWAVE TROUGHS FURTHER NORTH AND EAST. AIR MASS HAS DRIED
SIGNIFICANTLY OVER THE LAST 24 HOURS. MODELS AND FORECAST FAILED FROM
YESTERDAY. MID LEVEL RIDGING ENDED UP BEING STRONGER OVER THE AREA
WITH THE FRONT WELL SOUTH OF THE REGION.
AT JET LEVEL APPEARED TO INITIALIZE FINE. MODELS WERE NOT TOO FAR
APART AT MID LEVELS. THE CANADIAN AND GFS WERE DOING THE BEST WITH
THE OLDER ECMWF DOING THE WORST. THE HRRR WAS CATCHING THE INCOMING
THUNDERSTORM OUTFLOW WINDS/CLUSTER WELL AND WILL USE INITIALLY.
OUTSIDE OF THE POSSIBLE MESOSCALE AFFECTS OF THUNDERSTORM CLUSTER
MOVING IN...THE ECMWF WAS DOING THE BEST ON THE SURFACE WIND AND
PRESSURE FIELD. THE NAM...GFS AND UKMET WERE DOING THE BEST ON THE
LOW LEVEL THERMAL FIELD.
TODAY/TONIGHT...WILL BE MONITORING CONVECTIVE COMPLEX FOR AS LONG AS
POSSIBLE. THE BEHAVIOR OF THIS SYSTEM COULD HAVE SIGNIFICANT
IMPACTS ON THE FORECAST FOR THE REST OF THE DAY. FOR NOW USED THE
HRRR FOR THE POPS AND WINDS THIS MORNING SINCE IT IS CATCHING THIS
CLUSTER OF STORMS WELL.
MAIN JET LIFT REMAINS SOUTH OF THE AREA THROUGH THE DAY. MAIN AREA
OF SURFACE CONVERGENCE LIES WEST OF THE AREA WITH A SHORTWAVE TROUGH
APPROACHING THE WESTERN PORTION OF THE AREA LATE IN THE DAY. SO WILL
KEEP THE HIGHEST POPS OUT IN THE FAR WEST IN THE AFTERNOON. NOT SURE
IF TEMPERATURES WILL BE AFFECTED BY MORNING THUNDERSTORMS. AT THIS
TIME AM THINKING THEY WILL NOT BE AFFECTED TOO MUCH. SO WENT NEAR
TO JUST BELOW GUIDANCE.
QUESTIONS THEN BECOMES HOW FAR EAST THUNDERSTORMS WILL MAKE IT INTO
THE FORECAST AREA DURING THE NIGHT. AFTER 06Z MODELS SHOW A WEAK LEFT
FRONT QUADRANT AFFECTING THE SOUTHERN THIRD TO HALF OF THE AREA.
SHORTWAVE TROUGH MAKES A LITTLE PROGRESS TOWARD THE EAST WITH THE
INSTABILITY AXIS MAKING OVER THE EASTERN END OF THE AREA BY THE END
OF THE NIGHT. STORM MOTIONS ARE SOUTH TO SOUTHWEST. ELEVATED CINH
IS THE LOWEST AND BREAKABLE IN THE EAST BY THE END OF THE NIGHT. SO
WILL TRANSITION THE CHANCE POPS TOWARD THE EAST WHILE KEEPING SOME
KIND OF CHANCE IN THE WEST DUE TO THE PROXIMITY OF THE MID AND
UPPER LIFT REMAINS IN PLACE.
WEDNESDAY/WEDNESDAY NIGHT...SOME JET LIFT REMAINS NEAR THE SOUTHERN
PORTION OF THE AREA IN THE MORNING. BUT THEN THE JET GRADUALLY MOVES
SOUTH THE REST OF THE DAY AND LOOKS TO BE WELL SOUTH BY THE END OF
THE DAY. LINGERING LIFT FROM EXITING SHORTWAVE SHOULD ALLOW FOR A
SLIGHT CHANCE OF THUNDERSTORMS IN THE EAST IN THE MORNING.
THEN THE QUESTION IS WHERE DOES THE REDEVELOPMENT OCCUR IN THE
AFTERNOON. NEXT SHORTWAVE SHOULD BE JUST WEST OF THE COLORADO
BORDER BY LATE IN THE AFTERNOON WITH THE INSTABILITY AXIS JUST TO
THE EAST OF THAT. SO WILL START WITH A SLIGHT CHANCE NEAR THE BORDER
AND HAVE A LOW CHANCE IN THE EASTERN PORTION. THEN THIS SHOULD
PROGRESS TOWARD THE EAST FOR THE REST OF THE NIGHT.
MODELS DIFFER ON THE DEGREE THEY INCREASE THE WINDS. IT DEFINITELY
LOOKS LIKE IT WILL BE WINDY AND POSSIBLY CLOSE TO ADVISORY
CRITERIA. ALSO DEWPOINTS LOOK LIKE THEY BECOME LOW IN THE FAR WEST
WHERE COMBINED WITH THE STRONG WINDS COULD CAUSE FIRE WEATHER
ISSUES. MODELS WARMER THAN 24 HOURS AGO AND YESTERDAYS FORECAST.
CONSIDERING WILL NOT HAVE MUCH IF ANY DOWNSLOPE COMPONENT...AM
SKEPTICAL OF TOO BIG OF AN INCREASE.
THURSDAY/THURSDAY NIGHT...MODELS SHOW A BOUNDARY MOVE INTO THE AREA
AND THEN STALLING OR WAFFLING BACK AND FORTH. INITIALLY FOR THE DAY
ON THURSDAY...THERE DOES NOT APPEAR TO BE A LOT OF COOLING BEHIND
THIS BOUNDARY WITH VERY TOASTY MID LEVEL TEMPERATURES. ALSO
SOUNDINGS SHOW A DEEP DRY LAYER. SHORTWAVE TROUGH IS ALSO EXPECTED
TO MOVE THROUGH...MAINLY ACROSS THE NORTHWEST HALF. BY THE END OF THE
DAY THE LEFT FRONT QUADRANT LOOKS TO BE AFFECTING THE SOUTHEAST THIRD
OR JUST SOUTH OF THE AREA. DURING THE NIGHT THIS LIFT LOOKS TO REMAIN
NEAR TO THE SOUTHERN PORTION OF THE FORECAST AREA. SO DESPITE SOME
FAVORABLE PARAMETERS...WILL KEEP THIS WHOLE PERIOD DRY DUE TO THE MID
LEVEL TEMPERATURES AND VERY DEEP DRY LAYER.
MODELS CONTINUE THEIR WARMING TREND DESPITE THE PRESENCE OF A WIND
SHIFT. THE NORTHERN PORTION LOOKS TO BE THE MOST AFFECTED BY THE
BOUNDARY BUT NOT A WHOLE LOT. IT WILL DEFINITELY BE IN THE MIDDLE
90S THERE. GIVEN THE 850 MB TEMPERATURES IT WILL GET NEAR TO A
LITTLE ABOVE 100 DEGREES. TEMPERATURES MAY NEED TO BE RAISED EVEN
MORE.
.LONG TERM...(FRIDAY THROUGH MONDAY)
ISSUED AT 211 AM MDT TUE JUN 18 2013
LONG RANGE MODELS IN GENERAL AGREEMENT WITH UPPER LEVEL LOW PRESSURE
SYSTEM OVER THE PACIFIC NORTHWEST...WITH A TROUGH PATTERN OVER THE
WESTERN THIRD OF THE CONUS. RIDGE OVER THE SOUTHEAST REGION CREATES
MERIDIONAL FLOW PATTERN OVER THE CENTRAL PLAINS. AREAS OF STRONGEST
500 MB JET SHOULD REMAIN IN THE NORTHERN PLAINS. EMBEDDED
SHORTWAVES BEGIN TO MOVE THROUGH THE TRI STATE AREA FRIDAY EVENING.
UPPER LEVEL SHORTWAVE AND STRONGER LOWER LEVEL JET SHOULD AID IN
DEEPENING OF SURFACE LOW PRESSURE. DRY LINE AT THE SURFACE LOOKS
TO HAVE A STRONG GRADIENT OF APPROXIMATELY 30 DEGREES ACROSS WESTERN
KANSAS...WHICH COULD PROVIDE SOME SURFACE LIFT FOR AFTERNOON AND
EVENING CONVECTIVE DEVELOPMENT. HOWEVER, MODELS INDICATE THE DRY
LINE WILL BE STATIONARY AROUND THE CO/KS BORDER...WHICH WOULD NOT
INITIATE CONVECTION. CAPE/LI/AND K INDEX PARAMETERS ARE MOST
SUPPORTIVE OF CONVECTION TOWARDS CENTRAL KANSAS...WITH MARGINAL
VALUES AT BEST FOR THE TRI STATE AREA. DRY LINE LOOKS TO PROGRESS
MORE EASTWARD FOR SATURDAY AND SUNDAY...WITH INSTABILITY PARAMETERS
BECOMING MORE FAVORABLE FOR AFTERNOON CONVECTIVE DEVELOPMENT.
STRONG SOUTHERLY FLOW WITH WARM AIR ADVECTION WILL KEEP SURFACE
TEMPERATURES WARM THROUGHOUT THE EXTENDED FORECAST PERIOD...WITH
HIGH TEMPERATURES IN THE UPPER 80S TO MID 90S. STRONG PRESSURE
GRADIENT ACROSS THE SOUTHERN PLAINS WILL KEEP WIND SPEEDS BETWEEN 20
AND 30 MPH WITH HIGHER GUSTS THROUGHOUT THE AREA FOR THE WEEKEND.
850 MB LEVEL SHOWS GOOD SOUTHWEST FLOW WITH PLENTY OF WARM AIR
ADVECTION FOR MONDAY...WITH TEMPERATURES AROUND 33 C. SURFACE
TEMPERATURES SHOULD BE WARM AS WELL LOOK TO BE IN THE UPPER 90S FOR
MONDAY WITH DRIER AIR ACROSS THE REGION WITH SOUTH WINDS SHIFT TO
SOUTHWEST. SOME LOCATIONS COULD SEE TRIPLE DIGITS FOR HIGH
TEMPERATURES.
THE MAIN STORY FOR THE PERIOD IS THE RETURN OF WARM TEMPERATURES TO
THE AREA. THE BEST CHANCES FOR PRECIPITATION WOULD BE SUNDAY
AFTERNOON...BUT CHANCES FOR RAIN SHOWERS AND THUNDERSTORMS EXIST
SATURDAY AFTERNOON THROUGH MONDAY AFTERNOON. AN UPPER LEVEL RIDGE
LOOKS TO BUILD INTO THE REGION FOR TUESDAY...LOOKING TO PROVIDE
FAIR WEATHER FOR THE MIDDLE OF NEXT WEEK WITH A CONTINUATION OF
WARM TEMPERATURES.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z WEDNESDAY MORNING)
ISSUED AT 530 AM MDT TUE JUN 18 2013
LOW PRESSURE SYSTEM TO THE WEST OF THE TAF SITES WILL HELP PRODUCE
AFTERNOON AND EVENING THUNDERSTORMS AT KGLD AND KMCK. THUNDERSTORMS
SHOULD BE PAST KMCK AT THE START OF THE TAF PERIOD...HOWEVER SHOWERS
WILL LINGER NEAR THE TERMINAL. WINDS FOR BOTH SITES WILL BE
VARIABLE IN DIRECTION FOR EARLY IN THE TAF PERIOD AND THEN CHANGING
TO SOUTH. CEILINGS AND VISIBILITIES ARE EXPECTED TO BE VFR
THROUGHOUT THE PERIOD. THUNDERSTORMS ARE LIKELY TO OCCUR AT BOTH
SITES LATER IN THE TAF PERIOD...BUT CONFIDENCE IS LOW AT THIS TIME
AS TO EXACTLY WHERE STORMS WILL PASS. THEREFORE...ONLY VICINITY
MENTIONS ARE IN TAFS FOR NOW.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
SHORT TERM...BULLER
LONG TERM...MK
AVIATION...MK
AREA FORECAST DISCUSSION
NWS GOODLAND KS
358 AM MDT TUE JUN 18 2013
.SHORT TERM...(TODAY THROUGH THURSDAY NIGHT)
ISSUED AT 358 AM MDT TUE JUN 18 2013
FORECAST PROBLEMS WILL BE THUNDERSTORM CHANCES AND HOW HOT DOES IT
GET. SATELLITE CONTINUING TO SHOW AN AMPLIFIED AND BLOCKY PATTERN
OVER THE CENTRAL/EASTERN PACIFIC INTO WESTERN NORTH AMERICA. SUBTLE
SHORTWAVE TROUGHS MOVING THROUGH THE FLOW WITH THE STRONGEST
SHORTWAVE TROUGHS FURTHER NORTH AND EAST. AIR MASS HAS DRIED
SIGNIFICANTLY OVER THE LAST 24 HOURS. MODELS AND FORECAST FAILED FROM
YESTERDAY. MID LEVEL RIDGING ENDED UP BEING STRONGER OVER THE AREA
WITH THE FRONT WELL SOUTH OF THE REGION.
AT JET LEVEL APPEARED TO INITIALIZE FINE. MODELS WERE NOT TOO FAR
APART AT MID LEVELS. THE CANADIAN AND GFS WERE DOING THE BEST WITH
THE OLDER ECMWF DOING THE WORST. THE HRRR WAS CATCHING THE INCOMING
THUNDERSTORM OUTFLOW WINDS/CLUSTER WELL AND WILL USE INITIALLY.
OUTSIDE OF THE POSSIBLE MESOSCALE AFFECTS OF THUNDERSTORM CLUSTER
MOVING IN...THE ECMWF WAS DOING THE BEST ON THE SURFACE WIND AND
PRESSURE FIELD. THE NAM...GFS AND UKMET WERE DOING THE BEST ON THE
LOW LEVEL THERMAL FIELD.
TODAY/TONIGHT...WILL BE MONITORING CONVECTIVE COMPLEX FOR AS LONG AS
POSSIBLE. THE BEHAVIOR OF THIS SYSTEM COULD HAVE SIGNIFICANT
IMPACTS ON THE FORECAST FOR THE REST OF THE DAY. FOR NOW USED THE
HRRR FOR THE POPS AND WINDS THIS MORNING SINCE IT IS CATCHING THIS
CLUSTER OF STORMS WELL.
MAIN JET LIFT REMAINS SOUTH OF THE AREA THROUGH THE DAY. MAIN AREA
OF SURFACE CONVERGENCE LIES WEST OF THE AREA WITH A SHORTWAVE TROUGH
APPROACHING THE WESTERN PORTION OF THE AREA LATE IN THE DAY. SO WILL
KEEP THE HIGHEST POPS OUT IN THE FAR WEST IN THE AFTERNOON. NOT SURE
IF TEMPERATURES WILL BE AFFECTED BY MORNING THUNDERSTORMS. AT THIS
TIME AM THINKING THEY WILL NOT BE AFFECTED TOO MUCH. SO WENT NEAR
TO JUST BELOW GUIDANCE.
QUESTIONS THEN BECOMES HOW FAR EAST THUNDERSTORMS WILL MAKE IT INTO
THE FORECAST AREA DURING THE NIGHT. AFTER 06Z MODELS SHOW A WEAK LEFT
FRONT QUADRANT AFFECTING THE SOUTHERN THIRD TO HALF OF THE AREA.
SHORTWAVE TROUGH MAKES A LITTLE PROGRESS TOWARD THE EAST WITH THE
INSTABILITY AXIS MAKING OVER THE EASTERN END OF THE AREA BY THE END
OF THE NIGHT. STORM MOTIONS ARE SOUTH TO SOUTHWEST. ELEVATED CINH
IS THE LOWEST AND BREAKABLE IN THE EAST BY THE END OF THE NIGHT. SO
WILL TRANSITION THE CHANCE POPS TOWARD THE EAST WHILE KEEPING SOME
KIND OF CHANCE IN THE WEST DUE TO THE PROXIMITY OF THE MID AND
UPPER LIFT REMAINS IN PLACE.
WEDNESDAY/WEDNESDAY NIGHT...SOME JET LIFT REMAINS NEAR THE SOUTHERN
PORTION OF THE AREA IN THE MORNING. BUT THEN THE JET GRADUALLY MOVES
SOUTH THE REST OF THE DAY AND LOOKS TO BE WELL SOUTH BY THE END OF
THE DAY. LINGERING LIFT FROM EXITING SHORTWAVE SHOULD ALLOW FOR A
SLIGHT CHANCE OF THUNDERSTORMS IN THE EAST IN THE MORNING.
THEN THE QUESTION IS WHERE DOES THE REDEVELOPMENT OCCUR IN THE
AFTERNOON. NEXT SHORTWAVE SHOULD BE JUST WEST OF THE COLORADO
BORDER BY LATE IN THE AFTERNOON WITH THE INSTABILITY AXIS JUST TO
THE EAST OF THAT. SO WILL START WITH A SLIGHT CHANCE NEAR THE BORDER
AND HAVE A LOW CHANCE IN THE EASTERN PORTION. THEN THIS SHOULD
PROGRESS TOWARD THE EAST FOR THE REST OF THE NIGHT.
MODELS DIFFER ON THE DEGREE THEY INCREASE THE WINDS. IT DEFINITELY
LOOKS LIKE IT WILL BE WINDY AND POSSIBLY CLOSE TO ADVISORY
CRITERIA. ALSO DEWPOINTS LOOK LIKE THEY BECOME LOW IN THE FAR WEST
WHERE COMBINED WITH THE STRONG WINDS COULD CAUSE FIRE WEATHER
ISSUES. MODELS WARMER THAN 24 HOURS AGO AND YESTERDAYS FORECAST.
CONSIDERING WILL NOT HAVE MUCH IF ANY DOWNSLOPE COMPONENT...AM
SKEPTICAL OF TOO BIG OF AN INCREASE.
THURSDAY/THURSDAY NIGHT...MODELS SHOW A BOUNDARY MOVE INTO THE AREA
AND THEN STALLING OR WAFFLING BACK AND FORTH. INITIALLY FOR THE DAY
ON THURSDAY...THERE DOES NOT APPEAR TO BE A LOT OF COOLING BEHIND
THIS BOUNDARY WITH VERY TOASTY MID LEVEL TEMPERATURES. ALSO
SOUNDINGS SHOW A DEEP DRY LAYER. SHORTWAVE TROUGH IS ALSO EXPECTED
TO MOVE THROUGH...MAINLY ACROSS THE NORTHWEST HALF. BY THE END OF THE
DAY THE LEFT FRONT QUADRANT LOOKS TO BE AFFECTING THE SOUTHEAST THIRD
OR JUST SOUTH OF THE AREA. DURING THE NIGHT THIS LIFT LOOKS TO REMAIN
NEAR TO THE SOUTHERN PORTION OF THE FORECAST AREA. SO DESPITE SOME
FAVORABLE PARAMETERS...WILL KEEP THIS WHOLE PERIOD DRY DUE TO THE MID
LEVEL TEMPERATURES AND VERY DEEP DRY LAYER.
MODELS CONTINUE THEIR WARMING TREND DESPITE THE PRESENCE OF A WIND
SHIFT. THE NORTHERN PORTION LOOKS TO BE THE MOST AFFECTED BY THE
BOUNDARY BUT NOT A WHOLE LOT. IT WILL DEFINITELY BE IN THE MIDDLE
90S THERE. GIVEN THE 850 MB TEMPERATURES IT WILL GET NEAR TO A
LITTLE ABOVE 100 DEGREES. TEMPERATURES MAY NEED TO BE RAISED EVEN
MORE.
.LONG TERM...(FRIDAY THROUGH MONDAY)
ISSUED AT 211 AM MDT TUE JUN 18 2013
LONG RANGE MODELS IN GENERAL AGREEMENT WITH UPPER LEVEL LOW PRESSURE
SYSTEM OVER THE PACIFIC NORTHWEST...WITH A TROUGH PATTERN OVER THE
WESTERN THIRD OF THE CONUS. RIDGE OVER THE SOUTHEAST REGION CREATES
MERIDIONAL FLOW PATTERN OVER THE CENTRAL PLAINS. AREAS OF STRONGEST
500 MB JET SHOULD REMAIN IN THE NORTHERN PLAINS. EMBEDDED
SHORTWAVES BEGIN TO MOVE THROUGH THE TRI STATE AREA FRIDAY EVENING.
UPPER LEVEL SHORTWAVE AND STRONGER LOWER LEVEL JET SHOULD AID IN
DEEPENING OF SURFACE LOW PRESSURE. DRY LINE AT THE SURFACE LOOKS
TO HAVE A STRONG GRADIENT OF APPROXIMATELY 30 DEGREES ACROSS WESTERN
KANSAS...WHICH COULD PROVIDE SOME SURFACE LIFT FOR AFTERNOON AND
EVENING CONVECTIVE DEVELOPMENT. HOWEVER, MODELS INDICATE THE DRY
LINE WILL BE STATIONARY AROUND THE CO/KS BORDER...WHICH WOULD NOT
INITIATE CONVECTION. CAPE/LI/AND K INDEX PARAMETERS ARE MOST
SUPPORTIVE OF CONVECTION TOWARDS CENTRAL KANSAS...WITH MARGINAL
VALUES AT BEST FOR THE TRI STATE AREA. DRY LINE LOOKS TO PROGRESS
MORE EASTWARD FOR SATURDAY AND SUNDAY...WITH INSTABILITY PARAMETERS
BECOMING MORE FAVORABLE FOR AFTERNOON CONVECTIVE DEVELOPMENT.
STRONG SOUTHERLY FLOW WITH WARM AIR ADVECTION WILL KEEP SURFACE
TEMPERATURES WARM THROUGHOUT THE EXTENDED FORECAST PERIOD...WITH
HIGH TEMPERATURES IN THE UPPER 80S TO MID 90S. STRONG PRESSURE
GRADIENT ACROSS THE SOUTHERN PLAINS WILL KEEP WIND SPEEDS BETWEEN 20
AND 30 MPH WITH HIGHER GUSTS THROUGHOUT THE AREA FOR THE WEEKEND.
850 MB LEVEL SHOWS GOOD SOUTHWEST FLOW WITH PLENTY OF WARM AIR
ADVECTION FOR MONDAY...WITH TEMPERATURES AROUND 33 C. SURFACE
TEMPERATURES SHOULD BE WARM AS WELL LOOK TO BE IN THE UPPER 90S FOR
MONDAY WITH DRIER AIR ACROSS THE REGION WITH SOUTH WINDS SHIFT TO
SOUTHWEST. SOME LOCATIONS COULD SEE TRIPLE DIGITS FOR HIGH
TEMPERATURES.
THE MAIN STORY FOR THE PERIOD IS THE RETURN OF WARM TEMPERATURES TO
THE AREA. THE BEST CHANCES FOR PRECIPITATION WOULD BE SUNDAY
AFTERNOON...BUT CHANCES FOR RAIN SHOWERS AND THUNDERSTORMS EXIST
SATURDAY AFTERNOON THROUGH MONDAY AFTERNOON. AN UPPER LEVEL RIDGE
LOOKS TO BUILD INTO THE REGION FOR TUESDAY...LOOKING TO PROVIDE
FAIR WEATHER FOR THE MIDDLE OF NEXT WEEK WITH A CONTINUATION OF
WARM TEMPERATURES.
&&
.AVIATION....(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT)
ISSUED AT 1054 PM MDT MON JUN 17 2013
VFR CONDITIONS FORECAST FOR THE 6Z TAFS. RADAR INDICATES THE LINE
OF STORMS OVER THE NEBRASKA PANHANDLE IS DECLINING. IF THE OUTFLOW
BOUNDARY MOVES INTO THE AREA OVERNIGHT...THERE IS VERY LITTLE CINH
TO HOLD STORMS BACK FROM DEVELOPING. THE AREA AROUND KMCK LOOKS
THE MOST FAVORABLE FOR STORMS TO DEVELOP SO HAVE ADDED A TEMPO
GROUP MAINLY FOR THE POSSIBLE WINDS FROM THE STORMS. DID NOT
INCLUDE A TEMPO GROUP FOR KGLD SINCE THE FAVORABLE ENVIRONMENT
HAS A SHORTER WINDOW OF OPPORTUNITY.
AM NOT THINKING THERE WILL BE ANY FOG OVERNIGHT. SOUNDINGS SHOW
A VERY SHALLOW LAYER THAT NEARS SATURATION SO WILL NOT INCLUDE
FOG. EVEN LOW CLOUDS LOOK QUESTIONABLE SO WILL NOT BE INCLUDING
THEM IN THE TAFS EITHER.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
SHORT TERM...BULLER
LONG TERM...MK
AVIATION...JTL
AREA FORECAST DISCUSSION
NWS GOODLAND KS
214 AM MDT TUE JUN 18 2013
.UPDATE...
ISSUED AT 1008 PM MDT MON JUN 17 2013
SINCE NEARLY ALL OF THE STORM ACTIVITY HAS ENDED...AND AM NOT
ANTICIPATING ANY SEVERE WEATHER UNTIL LATER TONIGHT...WILL ALLOW
THE SEVERE THUNDERSTORM WATCH TO EXPIRE.
SOUNDINGS INDICATE SOME ELEVATED CAPE TO WORK WITH
OVERNIGHT...WITH VALUES OVER 1000J/KG IN THE NORTHEAST PART OF THE
AREA. THIS IS ABOUT THE SOME TIME THE STORMS OVER THE CENTRAL
NEBRASKA PANHANDLE WILL MOVE THROUGH...IF THEY LAST THAT LONG...SO
A COUPLE STRONG TO SEVERE STORMS ARE POSSIBLE.
UPDATE ISSUED AT 913 PM MDT MON JUN 17 2013
OVER THE LAST HOUR A LINE OF STORMS HAS DEVELOPED OVER THE
NEBRASKA PANHANDLE...SIMILAR TO WHERE THE EARLIER MODELS WERE SUGGESTING
A LINE WOULD DEVELOP. SINCE 850MB WINDS WILL BE FEEDING INTO THE
LINE OF STORMS AS THEY MOVE SOUTHEAST...AM THINKING THE STORMS MAY
HOLD TOGETHER AND MAKE IT TO THE TRI-STATE AREA. HOWEVER...THE
AMOUNT OF LIFT PRESENT AS THE STORMS MOVE IN IS A CONCERN. AS SUCH
WILL NOT GO TOO HIGH WITH PRECIP. CHANCES OVERNIGHT.
&&
.SHORT TERM...(THIS EVENING THROUGH TUESDAY)
ISSUED AT 245 PM MDT MON JUN 17 2013
EARLY AFTERNOON WV IMAGERY AND RAP H5 ANALYSIS SHOW NW FLOW OVER
CWA WITH H5 RIDGE ACROSS WESTERN US. AT THE SURFACE A FRONT
CURRENTLY...WITH AREA OF SURFACE CONVERGENCE JUST WEST OUR OUR CWA
WHERE ISOLATED THUNDERSTORMS ARE BEGGING TO INTENSIFY.
LATEST RAP ANALYSIS INDICATES MIXED LAYER CAPE IN EXCESS OF 1500
J/KG OVER OUR CWA AND SHOWS THIS INCREASING AS LAPSE RATES
CONTINUE TO STEEPEN. LATEST HRRR SHOWS THUNDERSTORM ACTIVITY OVER
EASTERN COLORADO EXPANDING IN COVERAGE AND MOVING EAST THROUGH THE
AFTERNOON. NAM CONTINUES TO SHOW WIDESPREAD CONVECTIVELY INDUCED QPF
IN PLACE THROUGH THE EVENING OVERSPREADING THE CWA AND THEN
LINGERING OVERNIGHT AS A SHORTWAVE TROUGH UPSTREAM PUSHES SOUTH.
GFS/SREF SHOW A SIMILAR PATTERN...THOUGH QPF AMOUNTS ARE NOT QUITE
AS HIGH. SHEER PROFILES SHOULD IMPROVE THROUGH THE
AFTERNOON/EVENING WITH 0-6KM BULK SHEER 30-40KT...WHICH SHOULD
SUPPORT SEVERE THUNDERSTORMS. EARLY ON THIS AFTERNOON/EVENING
TORNADOES MAY BE POSSIBLE WITH STEEP LAPSE RATES IN PROXIMITY TO
SURFACE BOUNDARY/THUNDERSTORM INTERACTIONS. AIR MASS CONTINUES TO
BE VERY MOIST...AND CONSIDERING THE VERY SLOW STORM MOTION (5-10KT
0-6KM MEAN WIND) WE COULD SEE ISOLATED FLASH FLOOD RISK WITH THIS
ACTIVITY. AT THE VERY LEAST MOST LOCATIONS COULD SEE WIDESPREAD
0.5 TO 1.00" RAINFALL.
CURRENTLY THINKING WE SHOULD SEE AFTERNOON THUNDERSTORM ACTIVITY
MERGING INTO AT LEAST ONE CLUSTER/LINE AND SPREAD EAST THROUGH THE
EVENING...BEFORE ADDITIONAL ACTIVITY DEVELOPS WITH OVERNIGHT
SHORTWAVE. I ONLY MADE MINOR CHANGES TO INHERITED POP FORECAST
WITH MAIN CHANGE TO END THUNDERSTORM CHANCES EARLY TUE MORNING AS
WE SHOULD BE SUBSIDENT ON BACK SIDE OF DEPARTING PV ANOMALY.
GUIDANCE SUPPORTS THUNDERSTORMS REDEVELOPING BY WED AFTERNOON FROM
THE WEST TO THE EAST.
.LONG TERM...(FRIDAY THROUGH MONDAY)
ISSUED AT 211 AM MDT TUE JUN 18 2013
LONG RANGE MODELS IN GENERAL AGREEMENT WITH UPPER LEVEL LOW PRESSURE
SYSTEM OVER THE PACIFIC NORTHWEST...WITH A TROUGH PATTER OVER THE
WESTERN THIRD OF THE CONUS. RIDGE OVER THE SOUTHEAST REGION CREATES
MERIDIONAL FLOW PATTERN OVER THE CENTRAL PLAINS. AREAS OF STRONGEST
500 MB JET SHOULD REMAIN IN THE NORTHERN PLAINS. EMBEDDED
SHORTWAVES BEGIN TO MOVE THROUGH THE TRI STATE AREA FRIDAY EVENING.
UPPER LEVEL SHORTWAVE AND STRONGER LOWER LEVEL JET SHOULD AID IN
DEEPENING OF SURFACE LOW PRESSURE. DRY LINE AT THE SURFACE LOOKS
TO HAVE A STRONG GRADIENT OF APPROXIMATELY 30 DEGREES ACROSS WESTERN
KANSAS...WHICH COULD PROVIDE SOME SURFACE LIFT FOR AFTERNOON AND
EVENING CONVECTIVE DEVELOPMENT. HOWEVER, MODELS INDICATE THE DRY
LINE WILL BE STATIONARY AROUND THE CO/KS BORDER...WHICH WOULD NOT
INITIATE CONVECTION. CAPE/LI/AND K INDEX PARAMETERS ARE MOST
SUPPORTIVE OF CONVECTION TOWARDS CENTRAL KANSAS...WITH MARGINAL
VALUES AT BEST FOR THE TRI STATE AREA. DRY LINE LOOKS TO PROGRESS
MORE EASTWARD FOR SATURDAY AND SUNDAY...WITH INSTABILITY PARAMETERS
BECOMING MORE FAVORABLE FOR AFTERNOON CONVECTIVE DEVELOPMENT.
STRONG SOUTHERLY FLOW WITH WARM AIR ADVECTION WILL KEEP SURFACE
TEMPERATURES WARM THROUGHOUT THE EXTENDED FORECAST PERIOD...WITH
HIGH TEMPERATURES IN THE UPPER 80S TO MID 90S. STRONG PRESSURE
GRADIENT ACROSS THE SOUTHERN PLAINS WILL KEEP WIND SPEEDS BETWEEN 20
AND 30 MPH WITH HIGHER GUSTS THROUGHOUT THE AREA FOR THE WEEKEND.
850 MB LEVEL SHOWS GOOD SOUTHWEST FLOW WITH PLENTY OF WARM AIR
ADVECTION FOR MONDAY...WITH TEMPERATURES AROUND 33 C. SURFACE
TEMPERATURES SHOULD BE WARM AS WELL LOOK TO BE IN THE UPPER 90S FOR
MONDAY WITH DRIER AIR ACROSS THE REGION WITH SOUTH WINDS SHIFT TO
SOUTHWEST. SOME LOCATIONS COULD SEE TRIPLE DIGITS FOR HIGH
TEMPERATURES.
THE MAIN STORY FOR THE PERIOD IS THE RETURN OF WARM TEMPERATURES TO
THE AREA. THE BEST CHANCES FOR PRECIPITATION WOULD BE SUNDAY
AFTERNOON...BUT CHANCES FOR RAIN SHOWERS AND THUNDERSTORMS EXIST
SATURDAY AFTERNOON THROUGH MONDAY AFTERNOON. AN UPPER LEVEL RIDGE
LOOKS TO BUILD INTO THE REGION FOR TUESDAY...LOOKING TO PROVIDE
FAIR WEATHER FOR THE MIDDLE OF NEXT WEEK WITH A CONTINUATION OF
WARM TEMPERATURES.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT)
ISSUED AT 1054 PM MDT MON JUN 17 2013
VFR CONDITIONS FORECAST FOR THE 6Z TAFS. RADAR INDICATES THE LINE
OF STORMS OVER THE NEBRASKA PANHANDLE IS DECLINING. IF THE OUTFLOW
BOUNDARY MOVES INTO THE AREA OVERNIGHT...THERE IS VERY LITTLE CINH
TO HOLD STORMS BACK FROM DEVELOPING. THE AREA AROUND KMCK LOOKS
THE MOST FAVORABLE FOR STORMS TO DEVELOP SO HAVE ADDED A TEMPO
GROUP MAINLY FOR THE POSSIBLE WINDS FROM THE STORMS. DID NOT
INCLUDE A TEMPO GROUP FOR KGLD SINCE THE FAVORABLE ENVIRONMENT
HAS A SHORTER WINDOW OF OPPORTUNITY.
AM NOT THINKING THERE WILL BE ANY FOG OVERNIGHT. SOUNDINGS SHOW
A VERY SHALLOW LAYER THAT NEARS SATURATION SO WILL NOT INCLUDE
FOG. EVEN LOW CLOUDS LOOK QUESTIONABLE SO WILL NOT BE INCLUDING
THEM IN THE TAFS EITHER.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
UPDATE...JTL
SHORT TERM...DR
LONG TERM...MK
AVIATION...JTL
AREA FORECAST DISCUSSION
NWS GOODLAND KS
1103 PM MDT MON JUN 17 2013
.UPDATE...
ISSUED AT 1008 PM MDT MON JUN 17 2013
SINCE NEARLY ALL OF THE STORM ACTIVITY HAS ENDED...AND AM NOT
ANTICIPATING ANY SEVERE WEATHER UNTIL LATER TONIGHT...WILL ALLOW
THE SEVERE THUNDERSTORM WATCH TO EXPIRE.
SOUNDINGS INDICATE SOME ELEVATED CAPE TO WORK WITH
OVERNIGHT...WITH VALUES OVER 1000J/KG IN THE NORTHEAST PART OF THE
AREA. THIS IS ABOUT THE SOME TIME THE STORMS OVER THE CENTRAL
NEBRASKA PANHANDLE WILL MOVE THROUGH...IF THEY LAST THAT LONG...SO
A COUPLE STRONG TO SEVERE STORMS ARE POSSIBLE.
UPDATE ISSUED AT 913 PM MDT MON JUN 17 2013
OVER THE LAST HOUR A LINE OF STORMS HAS DEVELOPED OVER THE
NEBRASKA PANHANDLE...SIMILAR TO WHERE THE EARLIER MODELS WERE SUGGESTING
A LINE WOULD DEVELOP. SINCE 850MB WINDS WILL BE FEEDING INTO THE
LINE OF STORMS AS THEY MOVE SOUTHEAST...AM THINKING THE STORMS MAY
HOLD TOGETHER AND MAKE IT TO THE TRI-STATE AREA. HOWEVER...THE
AMOUNT OF LIFT PRESENT AS THE STORMS MOVE IN IS A CONCERN. AS SUCH
WILL NOT GO TOO HIGH WITH PRECIP. CHANCES OVERNIGHT.
&&
.SHORT TERM...(THIS EVENING THROUGH TUESDAY)
ISSUED AT 245 PM MDT MON JUN 17 2013
EARLY AFTERNOON WV IMAGERY AND RAP H5 ANALYSIS SHOW NW FLOW OVER
CWA WITH H5 RIDGE ACROSS WESTERN US. AT THE SURFACE A FRONT
CURRENTLY...WITH AREA OF SURFACE CONVERGENCE JUST WEST OUR OUR CWA
WHERE ISOLATED THUNDERSTORMS ARE BEGGING TO INTENSIFY.
LATEST RAP ANALYSIS INDICATES MIXED LAYER CAPE IN EXCESS OF 1500
J/KG OVER OUR CWA AND SHOWS THIS INCREASING AS LAPSE RATES
CONTINUE TO STEEPEN. LATEST HRRR SHOWS THUNDERSTORM ACTIVITY OVER
EASTERN COLORADO EXPANDING IN COVERAGE AND MOVING EAST THROUGH THE
AFTERNOON. NAM CONTINUES TO SHOW WIDESPREAD CONVECTIVELY INDUCED QPF
IN PLACE THROUGH THE EVENING OVERSPREADING THE CWA AND THEN
LINGERING OVERNIGHT AS A SHORTWAVE TROUGH UPSTREAM PUSHES SOUTH.
GFS/SREF SHOW A SIMILAR PATTERN...THOUGH QPF AMOUNTS ARE NOT QUITE
AS HIGH. SHEER PROFILES SHOULD IMPROVE THROUGH THE
AFTERNOON/EVENING WITH 0-6KM BULK SHEER 30-40KT...WHICH SHOULD
SUPPORT SEVERE THUNDERSTORMS. EARLY ON THIS AFTERNOON/EVENING
TORNADOES MAY BE POSSIBLE WITH STEEP LAPSE RATES IN PROXIMITY TO
SURFACE BOUNDARY/THUNDERSTORM INTERACTIONS. AIR MASS CONTINUES TO
BE VERY MOIST...AND CONSIDERING THE VERY SLOW STORM MOTION (5-10KT
0-6KM MEAN WIND) WE COULD SEE ISOLATED FLASH FLOOD RISK WITH THIS
ACTIVITY. AT THE VERY LEAST MOST LOCATIONS COULD SEE WIDESPREAD
0.5 TO 1.00" RAINFALL.
CURRENTLY THINKING WE SHOULD SEE AFTERNOON THUNDERSTORM ACTIVITY
MERGING INTO AT LEAST ONE CLUSTER/LINE AND SPREAD EAST THROUGH THE
EVENING...BEFORE ADDITIONAL ACTIVITY DEVELOPS WITH OVERNIGHT
SHORTWAVE. I ONLY MADE MINOR CHANGES TO INHERITED POP FORECAST
WITH MAIN CHANGE TO END THUNDERSTORM CHANCES EARLY TUE MORNING AS
WE SHOULD BE SUBSIDENT ON BACK SIDE OF DEPARTING PV ANOMALY.
GUIDANCE SUPPORTS THUNDERSTORMS REDEVELOPING BY WED AFTERNOON FROM
THE WEST TO THE EAST.
.LONG TERM...(TUESDAY NIGHT THROUGH MONDAY)
ISSUED AT 210 PM MDT MON JUN 17 2013
A RIDGE WILL MOVE INTO THE PLAINS AND REMAIN THROUGH THURSDAY.
SURFACE HIGH PRESSURE WILL BE OVER THE CENTRAL PLAINS TUESDAY NIGHT.
LOW PRESSURE OVER WYOMING WEDNESDAY WILL DEVELOP SOUTH INTO EASTERN
COLORADO WEDNESDAY NIGHT. BY THURSDAY A TROUGH WILL BE POSITIONED
OVER NORTHWEST KANSAS,
STORMS WILL LIKELY FORM OVER EASTERN COLORADO EACH AFTERNOON
THROUGH WEDNESDAY DUE TO CONVERGENCE AND PROXIMITY TO THE SURFACE
TROUGH. MOISTURE AND INSTABILITY WILL BE FOCUSED IN THAT AREA.
PLAN TO GO WITH CHANCE POPS IN THAT AREA AND TO THE EAST WHERE
STEERING WINDS WILL MOVE THE STORMS. GENERALLY LOWER POPS WILL BE
USED IN THE EASTERN FA. THE TROUGH SHOULD BE EAST OF THE FA
THURSDAY SO PLAN TO CONTINUE THE DRY FORECAST/NIL POPS FOR THAT
PERIOD.
MIN TEMPERATURES TUESDAY AND WEDNESDAY NIGHTS WILL BE IN THE LOWER
TO MID 60S. MAX TEMPERATURES WEDNESDAY WILL REACH THE MID/UPPER 80S.
850 TEMPERATURES AROUND 30 WILL SUPPORT MID 90S FOR MAX TEMPERATURES
THURSDAY.
IN THE EXTENDED...(THURSDAY NIGHT THROUGH MONDAY)...UPPER FLOW WILL
BE SOUTHWEST THROUGH THIS PART OF THE FORECAST. A SURFACE TROUGH
WILL BE NEAR THE COLORADO BORDER AS WELL. IMPULSES MOVING THROUGH
THE FLOW WILL PRODUCE AT LEAST A SLIGHT CHANCE OF THUNDERSTORMS FROM
FRIDAY NIGHT THROUGH SUNDAY NIGHT. THE FORECAST WILL BE DRY WITH NIL
POPS THURSDAY NIGHT AND MONDAY.
MIN TEMPERATURES WILL RANGE FROM THE LOWER TO MID 60S WEST TO THE
UPPER 60S TO 70 EAST. MAX TEMPERATURES WILL RANGE IN THE 90S WITH
SOME UPPER 80S WEST.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT)
ISSUED AT 1054 PM MDT MON JUN 17 2013
VFR CONDITIONS FORECAST FOR THE 6Z TAFS. RADAR INDICATES THE LINE
OF STORMS OVER THE NEBRASKA PANHANDLE IS DECLINING. IF THE OUTFLOW
BOUNDARY MOVES INTO THE AREA OVERNIGHT...THERE IS VERY LITTLE CINH
TO HOLD STORMS BACK FROM DEVELOPING. THE AREA AROUND KMCK LOOKS
THE MOST FAVORABLE FOR STORMS TO DEVELOP SO HAVE ADDED A TEMPO
GROUP MAINLY FOR THE POSSIBLE WINDS FROM THE STORMS. DID NOT
INCLUDE A TEMPO GROUP FOR KGLD SINCE THE FAVORABLE ENVIRONMENT
HAS A SHORTER WINDOW OF OPPORTUNITY.
AM NOT THINKING THERE WILL BE ANY FOG OVERNIGHT. SOUNDINGS SHOW
A VERY SHALLOW LAYER THAT NEARS SATURATION SO WILL NOT INCLUDE
FOG. EVEN LOW CLOUDS LOOK QUESTIONABLE SO WILL NOT BE INCLUDING
THEM IN THE TAFS EITHER.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
UPDATE...JTL
SHORT TERM...DR
LONG TERM...FS
AVIATION...JTL
AREA FORECAST DISCUSSION
NWS GOODLAND KS
1013 PM MDT MON JUN 17 2013
.UPDATE...
ISSUED AT 1008 PM MDT MON JUN 17 2013
SINCE NEARLY ALL OF THE STORM ACTIVITY HAS ENDED...AND AM NOT
ANTICIPATING ANY SEVERE WEATHER UNTIL LATER TONIGHT...WILL ALLOW
THE SEVERE THUNDERSTORM WATCH TO EXPIRE.
SOUNDINGS INDICATE SOME ELEVATED CAPE TO WORK WITH
OVERNIGHT...WITH VALUES OVER 1000J/KG IN THE NORTHEAST PART OF THE
AREA. THIS IS ABOUT THE SOME TIME THE STORMS OVER THE CENTRAL
NEBRASKA PANHANDLE WILL MOVE THROUGH...IF THEY LAST THAT LONG...SO
A COUPLE STRONG TO SEVERE STORMS ARE POSSIBLE.
UPDATE ISSUED AT 913 PM MDT MON JUN 17 2013
OVER THE LAST HOUR A LINE OF STORMS HAS DEVELOPED OVER THE
NEBRASKA PANHANDLE...SIMILAR TO WHERE THE EARLIER MODELS WERE SUGGESTING
A LINE WOULD DEVELOP. SINCE 850MB WINDS WILL BE FEEDING INTO THE
LINE OF STORMS AS THEY MOVE SOUTHEAST...AM THINKING THE STORMS MAY
HOLD TOGETHER AND MAKE IT TO THE TRI-STATE AREA. HOWEVER...THE
AMOUNT OF LIFT PRESENT AS THE STORMS MOVE IN IS A CONCERN. AS SUCH
WILL NOT GO TOO HIGH WITH PRECIP. CHANCES OVERNIGHT.
&&
.SHORT TERM...(THIS EVENING THROUGH TUESDAY)
ISSUED AT 245 PM MDT MON JUN 17 2013
EARLY AFTERNOON WV IMAGERY AND RAP H5 ANALYSIS SHOW NW FLOW OVER
CWA WITH H5 RIDGE ACROSS WESTERN US. AT THE SURFACE A FRONT
CURRENTLY...WITH AREA OF SURFACE CONVERGENCE JUST WEST OUR OUR CWA
WHERE ISOLATED THUNDERSTORMS ARE BEGGING TO INTENSIFY.
LATEST RAP ANALYSIS INDICATES MIXED LAYER CAPE IN EXCESS OF 1500
J/KG OVER OUR CWA AND SHOWS THIS INCREASING AS LAPSE RATES
CONTINUE TO STEEPEN. LATEST HRRR SHOWS THUNDERSTORM ACTIVITY OVER
EASTERN COLORADO EXPANDING IN COVERAGE AND MOVING EAST THROUGH THE
AFTERNOON. NAM CONTINUES TO SHOW WIDESPREAD CONVECTIVELY INDUCED QPF
IN PLACE THROUGH THE EVENING OVERSPREADING THE CWA AND THEN
LINGERING OVERNIGHT AS A SHORTWAVE TROUGH UPSTREAM PUSHES SOUTH.
GFS/SREF SHOW A SIMILAR PATTERN...THOUGH QPF AMOUNTS ARE NOT QUITE
AS HIGH. SHEER PROFILES SHOULD IMPROVE THROUGH THE
AFTERNOON/EVENING WITH 0-6KM BULK SHEER 30-40KT...WHICH SHOULD
SUPPORT SEVERE THUNDERSTORMS. EARLY ON THIS AFTERNOON/EVENING
TORNADOES MAY BE POSSIBLE WITH STEEP LAPSE RATES IN PROXIMITY TO
SURFACE BOUNDARY/THUNDERSTORM INTERACTIONS. AIR MASS CONTINUES TO
BE VERY MOIST...AND CONSIDERING THE VERY SLOW STORM MOTION (5-10KT
0-6KM MEAN WIND) WE COULD SEE ISOLATED FLASH FLOOD RISK WITH THIS
ACTIVITY. AT THE VERY LEAST MOST LOCATIONS COULD SEE WIDESPREAD
0.5 TO 1.00" RAINFALL.
CURRENTLY THINKING WE SHOULD SEE AFTERNOON THUNDERSTORM ACTIVITY
MERGING INTO AT LEAST ONE CLUSTER/LINE AND SPREAD EAST THROUGH THE
EVENING...BEFORE ADDITIONAL ACTIVITY DEVELOPS WITH OVERNIGHT
SHORTWAVE. I ONLY MADE MINOR CHANGES TO INHERITED POP FORECAST
WITH MAIN CHANGE TO END THUNDERSTORM CHANCES EARLY TUE MORNING AS
WE SHOULD BE SUBSIDENT ON BACK SIDE OF DEPARTING PV ANOMALY.
GUIDANCE SUPPORTS THUNDERSTORMS REDEVELOPING BY WED AFTERNOON FROM
THE WEST TO THE EAST.
.LONG TERM...(TUESDAY NIGHT THROUGH MONDAY)
ISSUED AT 210 PM MDT MON JUN 17 2013
A RIDGE WILL MOVE INTO THE PLAINS AND REMAIN THROUGH THURSDAY.
SURFACE HIGH PRESSURE WILL BE OVER THE CENTRAL PLAINS TUESDAY NIGHT.
LOW PRESSURE OVER WYOMING WEDNESDAY WILL DEVELOP SOUTH INTO EASTERN
COLORADO WEDNESDAY NIGHT. BY THURSDAY A TROUGH WILL BE POSITIONED
OVER NORTHWEST KANSAS,
STORMS WILL LIKELY FORM OVER EASTERN COLORADO EACH AFTERNOON
THROUGH WEDNESDAY DUE TO CONVERGENCE AND PROXIMITY TO THE SURFACE
TROUGH. MOISTURE AND INSTABILITY WILL BE FOCUSED IN THAT AREA.
PLAN TO GO WITH CHANCE POPS IN THAT AREA AND TO THE EAST WHERE
STEERING WINDS WILL MOVE THE STORMS. GENERALLY LOWER POPS WILL BE
USED IN THE EASTERN FA. THE TROUGH SHOULD BE EAST OF THE FA
THURSDAY SO PLAN TO CONTINUE THE DRY FORECAST/NIL POPS FOR THAT
PERIOD.
MIN TEMPERATURES TUESDAY AND WEDNESDAY NIGHTS WILL BE IN THE LOWER
TO MID 60S. MAX TEMPERATURES WEDNESDAY WILL REACH THE MID/UPPER 80S.
850 TEMPERATURES AROUND 30 WILL SUPPORT MID 90S FOR MAX TEMPERATURES
THURSDAY.
IN THE EXTENDED...(THURSDAY NIGHT THROUGH MONDAY)...UPPER FLOW WILL
BE SOUTHWEST THROUGH THIS PART OF THE FORECAST. A SURFACE TROUGH
WILL BE NEAR THE COLORADO BORDER AS WELL. IMPULSES MOVING THROUGH
THE FLOW WILL PRODUCE AT LEAST A SLIGHT CHANCE OF THUNDERSTORMS FROM
FRIDAY NIGHT THROUGH SUNDAY NIGHT. THE FORECAST WILL BE DRY WITH NIL
POPS THURSDAY NIGHT AND MONDAY.
MIN TEMPERATURES WILL RANGE FROM THE LOWER TO MID 60S WEST TO THE
UPPER 60S TO 70 EAST. MAX TEMPERATURES WILL RANGE IN THE 90S WITH
SOME UPPER 80S WEST.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z TUESDAY EVENING)
ISSUED AT 544 PM MDT MON JUN 17 2013
MVFR TO VFR CONDITIONS FORECAST FOR THE 0Z TAFS. LATEST
RADAR/SATELLITE INDICATE STORMS DEVELOPING/MOVING EAST AHEAD OF AN
UPPER LEVEL TROUGH OVER COLORADO. STORM MOTIONS ARE AROUND 5-10
KTS SO STORMS WILL NOT QUICKLY MOVE THROUGH THE TAF SITES. BASED
ON THE LATEST SPEEDS OF THE LINE OF STORMS...AM ANTICIPATING THEM
TO MOVE THROUGH BOTH SITES DURING THE EVENING. OVERNIGHT MODELS
ARE INDICATING ANOTHER AREA OF STORMS MOVES THROUGH...MAINLY
IMPACTING KGLD. AM SOMEWHAT SKEPTICAL OF THIS SINCE THE SYNOPTIC
SETUP IS SIMILAR TO YESTERDAY WITH ONE LINE OF STORMS MOVING THROUGH...BUT
THE NEAR TERM MODELS ARE BEGINNING TO INDICATE THIS AS WELL. WILL
WAIT UNTIL THE NEXT TAF ISSUANCE TO ADDRESS THIS. CLOSE TO EARLY
MORNING FOG/LOW CLOUDS MAY DEVELOP DUE TO RAINFALL FROM OVERNIGHT
AND THE LIGHT WINDS. SOUNDINGS ARE NOT FAVORABLE FOR EITHER TO
FORM AT THIS TIME...SO WILL ALSO RE-ADDRESS THIS FOR THE NEXT SET
OF TAFS.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
UPDATE...JTL
SHORT TERM...DR
LONG TERM...FS
AVIATION...JTL
AREA FORECAST DISCUSSION
NWS LOUISVILLE KY
107 PM EDT TUE JUN 18 2013
...Updated Aviation Discussion...
.FORECAST UPDATE...
Issued at 955 AM EDT Tue Jun 18 2013
Morning cloud cover across the southeast forecast area should keep
highs temperatures several degrees under readings to the northwest.
Bumped highs up a couple of degrees in the latter region given good
heating getting started now. Still think initiation in that area
will hold off till at least mid afternoon so have tweaked pop grids
to cover that. Also reduced afternoon chances across the south,
where lack of heating should limit coverage. The NARRE and to a
lesser extent the latest HRRR agree with this scenario.
As for severe chances, shortwave trough over northern Iowa should
move to the Chicago area by late afternoon. Falling heights ahead of
this trough should bring cooler air aloft. Afternoon forecast
soundings indicate less moisture to work with and CAPEs not as high
as yesterday, but lower wet-bulb zeroes. With drier air in the mid
levels, think damaging wind gusts and hail will be the main threats
as storm clusters develop over the north and move southward.
Issued at 635 AM EDT Tue Jun 18 2013
Area of light rain continues to shift slowly eastward this morning.
Main area of rain should be east of I-65 after 12Z and then exit the
I-75 corridor by mid-morning. Drier air to the northwest will move
into the region this morning which should allow skies to partially
clear from the west to the east. Current forecast has this well in
hand, so only minor updates were made to the grids to better time
the exit of the rainfall this morning.
&&
.SHORT TERM (Now through Wednesday)...
Issued at 324 AM EDT Mon Jun 18 2013
Radar continues to show widespread light rain continuing across the
forecast area this morning. Convectively induced MCV continues to
push through middle Tennessee this morning with the heaviest
activity mainly staying to our south. Some moderate rain showers
will be possible across our southern Kentucky counties over the next
few hours...and a rumble of thunder or two can not be ruled out.
Elsewhere, light rain is beginning to diminish across our northwest
and western sections. Expect to see precipitation come to an end
toward sunrise over our northwest sections. Additional convection
is forecast to develop just to our northeast...between Indianapolis
and Covington later this morning...according to our local WRF model
run. Indeed, convection has developed over the last hour in this
general area. This activity is forecast to slide southeast and may
affect our far NE counties after sunrise. However, the local WRF
shows this activity decaying in the 13-14Z time frame. Temperatures
this morning will continue to be nearly steady state with lower to
middle 60s in the north and upper 60s to around 70 in the south.
Patchy fog will be a possibility in the typical low-lying and fog
prone areas until sunrise.
Somewhat of a complicated and overall low confidence forecast today
regarding cloud cover and additional convection. Widespread
convective debris will initially limit our solar insolation this
morning...keeping morning temperatures in the lower to middle 70s.
However, as the afternoon wears on, we should see cloud cover
decrease...especially across the west and northwestern sections
which will allow temperatures to warm into the lower to middle 80s.
Real question mark is over the east...where cloud cover may keep
temperatures in the upper 70s to around 80. Should clouds break up
faster, temperatures in future forecasts may need to be increased
over there.
As we heat up, we will destabilize once again thanks in part to
slightly cooler mid-level temperatures which will allow lapse rates
to approach 7 C/km. The afternoon heating combined with dewpoints
in the 60s should yield a moderately unstable atmosphere resulting
in isolated-scattered convection to develop across the region. With
this in mind...plan on keeping isolated-scattered PoPs in the
forecast for this afternoon.
More interesting convective development is possible late this
afternoon and evening as mid-level wave dives down from the Dakotas
into the Ohio Valley. As this feature pulls into the region, it
will encounter the moderately unstable and weakly sheared
atmosphere. Overall shear is not that great as we will be located
on the southern edge of the westerly flow with values pegged at 35
to maybe 40 kts. Latest high resolution NAM...WRF...and LMK WRF
models all develop convection across central Indiana this afternoon
and then drop it southeast into our southern Indiana counties by
this evening. This activity should continue into areas south of the
Ohio River early this evening, but is expected to weaken with the
loss of heating and increasing PBL stability. Some storms could be
on the strong to severe side this afternoon across our northern
sections. Based on the severe parameters of shear/instability that
damaging winds and near severe hail would be possible. Overall, feel
that the threat is likely to be more to our north where the stronger
shear would be located (up around the I-70 corridor). After the
activity dissipates, clear to partly cloudy skies are expected for
the overnight period with lows in the lower-middle 60s.
More quiet and tranquil weather looks likely on Wednesday with
afternoon highs warming into the lower to middle 80s.
.LONG TERM (Wednesday Night through Monday)...
Issued at 252 AM EDT Tue Jun 18 2013
The long term will be fairly quiet with just occasional slight
chances for thunderstorms. At the surface high pressure will slide
east of the region early in the period and we will then remain in
between the high pressure to the east and low pressure to the west.
Aloft a ridge will build from Texas to the Lower Mississippi River
Valley and then shift slowly eastward.
Mainly dry conditions are expected through the long term. A few
different weak disturbances may bring a slight chance of showers
thunderstorms to south central Kentucky on Friday, to northeastern
portions of the forecast area on Sunday, and to the whole area on
Monday. These storms are not expected to be widespread at this time.
Temperatures will warm into this weekend. Highs Saturday through
Monday are expected to top out in the upper 80s to lower 90s. Lows
will go from the lower 60s on Thursday morning to upper 60s and
lower 70s this weekend.
&&
.AVIATION (18Z TAF Update)...
Issued at 105 PM EDT Tue Jun 18 2013
A shortwave trough crossing the IA/IL border now will continue
dropping southeast today. This system, along with a frontal boundary
to our north, will force scattered storms to develop late this
afternoon. Think the best chance for timing purposes will run in the
evening hours at the KSDF and KLEX terminals. The threat is not zero
at BWG later, but think it is low enough to keep out of the TAFs at
this time. As storms develop to our north and moving
south/southeast, we likely will amend for tempo groups. Once the
front drops south of the region tonight, the rain chance will end
and next up will be chances for fog overnight. For now have all
three sites going to MVFR, as dewpoint drop behind the front should
not occur till later in the morning.
&&
.LMK WATCHES/WARNINGS/ADVISORIES...
IN...NONE.
KY...NONE.
$$
Updates..........MJ/RJS
Short Term.......MJ
Long Term........EER
Aviation.........RJS
AREA FORECAST DISCUSSION
NWS LOUISVILLE KY
956 AM EDT TUE JUN 18 2013
.FORECAST UPDATE...
Issued at 955 AM EDT Tue Jun 18 2013
Morning cloud cover across the southeast forecast area should keep
highs temperatures several degrees under readings to the northwest.
Bumped highs up a couple of degrees in the latter region given good
heating getting started now. Still think initiation in that area
will hold off till at least mid afternoon so have tweaked pop grids
to cover that. Also reduced afternoon chances across the south,
where lack of heating should limit coverage. The NARRE and to a
lesser extent the latest HRRR agree with this scenario.
As for severe chances, shortwave trough over northern Iowa should
move to the Chicago area by late afternoon. Falling heights ahead of
this trough should bring cooler air aloft. Afternoon forecast
soundings indicate less moisture to work with and CAPEs not as high
as yesterday, but lower wet-bulb zeroes. With drier air in the mid
levels, think damaging wind gusts and hail will be the main threats
as storm clusters develop over the north and move southward.
Issued at 635 AM EDT Tue Jun 18 2013
Area of light rain continues to shift slowly eastward this morning.
Main area of rain should be east of I-65 after 12Z and then exit the
I-75 corridor by mid-morning. Drier air to the northwest will move
into the region this morning which should allow skies to partially
clear from the west to the east. Current forecast has this well in
hand, so only minor updates were made to the grids to better time
the exit of the rainfall this morning.
&&
.SHORT TERM (Now through Wednesday)...
Issued at 324 AM EDT Mon Jun 18 2013
Radar continues to show widespread light rain continuing across the
forecast area this morning. Convectively induced MCV continues to
push through middle Tennessee this morning with the heaviest
activity mainly staying to our south. Some moderate rain showers
will be possible across our southern Kentucky counties over the next
few hours...and a rumble of thunder or two can not be ruled out.
Elsewhere, light rain is beginning to diminish across our northwest
and western sections. Expect to see precipitation come to an end
toward sunrise over our northwest sections. Additional convection
is forecast to develop just to our northeast...between Indianapolis
and Covington later this morning...according to our local WRF model
run. Indeed, convection has developed over the last hour in this
general area. This activity is forecast to slide southeast and may
affect our far NE counties after sunrise. However, the local WRF
shows this activity decaying in the 13-14Z time frame. Temperatures
this morning will continue to be nearly steady state with lower to
middle 60s in the north and upper 60s to around 70 in the south.
Patchy fog will be a possibility in the typical low-lying and fog
prone areas until sunrise.
Somewhat of a complicated and overall low confidence forecast today
regarding cloud cover and additional convection. Widespread
convective debris will initially limit our solar insolation this
morning...keeping morning temperatures in the lower to middle 70s.
However, as the afternoon wears on, we should see cloud cover
decrease...especially across the west and northwestern sections
which will allow temperatures to warm into the lower to middle 80s.
Real question mark is over the east...where cloud cover may keep
temperatures in the upper 70s to around 80. Should clouds break up
faster, temperatures in future forecasts may need to be increased
over there.
As we heat up, we will destabilize once again thanks in part to
slightly cooler mid-level temperatures which will allow lapse rates
to approach 7 C/km. The afternoon heating combined with dewpoints
in the 60s should yield a moderately unstable atmosphere resulting
in isolated-scattered convection to develop across the region. With
this in mind...plan on keeping isolated-scattered PoPs in the
forecast for this afternoon.
More interesting convective development is possible late this
afternoon and evening as mid-level wave dives down from the Dakotas
into the Ohio Valley. As this feature pulls into the region, it
will encounter the moderately unstable and weakly sheared
atmosphere. Overall shear is not that great as we will be located
on the southern edge of the westerly flow with values pegged at 35
to maybe 40 kts. Latest high resolution NAM...WRF...and LMK WRF
models all develop convection across central Indiana this afternoon
and then drop it southeast into our southern Indiana counties by
this evening. This activity should continue into areas south of the
Ohio River early this evening, but is expected to weaken with the
loss of heating and increasing PBL stability. Some storms could be
on the strong to severe side this afternoon across our northern
sections. Based on the severe parameters of shear/instability that
damaging winds and near severe hail would be possible. Overall, feel
that the threat is likely to be more to our north where the stronger
shear would be located (up around the I-70 corridor). After the
activity dissipates, clear to partly cloudy skies are expected for
the overnight period with lows in the lower-middle 60s.
More quiet and tranquil weather looks likely on Wednesday with
afternoon highs warming into the lower to middle 80s.
.LONG TERM (Wednesday Night through Monday)...
Issued at 252 AM EDT Tue Jun 18 2013
The long term will be fairly quiet with just occasional slight
chances for thunderstorms. At the surface high pressure will slide
east of the region early in the period and we will then remain in
between the high pressure to the east and low pressure to the west.
Aloft a ridge will build from Texas to the Lower Mississippi River
Valley and then shift slowly eastward.
Mainly dry conditions are expected through the long term. A few
different weak disturbances may bring a slight chance of showers
thunderstorms to south central Kentucky on Friday, to northeastern
portions of the forecast area on Sunday, and to the whole area on
Monday. These storms are not expected to be widespread at this time.
Temperatures will warm into this weekend. Highs Saturday through
Monday are expected to top out in the upper 80s to lower 90s. Lows
will go from the lower 60s on Thursday morning to upper 60s and
lower 70s this weekend.
&&
.AVIATION (12Z TAF Update)...
Issued at 645 AM EDT Tue Jun 18 2013
Widespread rain shower activity continues to press eastward this
morning. The rain has already cleared KSDF and will clear KBWG and
KLEX within the next hour or so. After that, VFR conditions are
expected across the region for the remainder of the morning and into
the afternoon hours.
Some isolated-scattered convection will be possible later this
afternoon due to convective heating. In addition, a mid-level
disturbance is forecast to drop into the region from the NW later
this evening and may spawn additional convection across southern
Indiana which may affect KSDF and KLEX after 19/00Z.
&&
.LMK WATCHES/WARNINGS/ADVISORIES...
IN...NONE.
KY...NONE.
$$
Updates..........MJ/RJS
Short Term.......MJ
Long Term........EER
Aviation.........MJ
AREA FORECAST DISCUSSION
NWS LOUISVILLE KY
112 AM EDT TUE JUN 18 2013
...Updated Aviation Discussion...
.FORECAST UPDATE...
Issued at 105 AM EDT Tue Jun 18 2013
Did a quick update to remove thunder from the forecast as convection
continues to slowly wind down. Thunder is now contained mainly to
far NE KY early this morning. Convectively induced MCV is churning
across southwestern TN this morning. Latest short range LMK WRF,
RAP and HRRR runs suggest that this will pivot eastward through the
night and mainly affect middle TN. Showers are expected to continue
through much of the overnight hours with a diminishing trend
developing across southwest IN and portions of north-central
Kentucky later this morning. More heavier rainfall will be possible
overnight along the KY/TN border as the MCV passes by. A rumble or
two of thunder will be possible with this activity...but feel the
bulk of that will be to our south. With the rain ending and
temperatures cooling, did add in some patchy fog to the forecast as
we`re likely to see that develop in the typical low-lying and fog
prone areas.
Update issued at 848 PM EDT Mon Jun 17 2013
Activity continues to wane this evening, as surface temperatures
have cooled resulting in diminishing surface instability. However,
a wave of isentropic ascent in advance of the approaching shortwave
trough continues to slide northeast across Kentucky, which should
keep showers and a few thunderstorms going for the next several
hours across portions of Kentucky and southern Indiana.
Southern Kentucky is enjoying a break for now, but additional
showers and isolated thunderstorms will continue to develop
northeast of a surface low progged to slide through TN. It remains
unclear just how widespread this activity will be, but a low-level
jet of 25-35 knots should help keep coverage up enough to warrant
50-60 pops across southern KY. Forecast soundings do show some
slight warming aloft, and with the loss of any surface-based
instability, think thunder overnight will remain rather isolated,
thus have kept only isolated thunder in the grids.
&&
.SHORT TERM (Tonight through Tuesday night)...
Issued at 340 PM EDT Mon Jun 17 2013
Broadly cyclonic upper flow over the eastern CONUS will carry a
couple disturbances over the Ohio Valley through Tuesday night.
Moist and unstable low levels will fuel convection, but forecast
confidence is low due to uncertainty in timing of upper features,
and how convection will change the atmosphere for the next
disturbance.
Boundary extending from near Brandenburg to between Danville and
Somerset is serving as a focus for convection. Slow-moving storms
will mostly be heavy rain producers, but FTK has gotten 42 mph gusts
and pea-sized hail out of an isolated cell in the last 30 min. Will
highlight heavy rain and pulse wind potential from storms this
afternoon, but organized SVR is not likely.
Will ramp POPs up south of the boundary to account for activity that
may spread in from western KY/TN as we head into the evening. The
main shortwave will come through after midnight, so will expand POPs
northward for that. Likely POP south of the Parkways, but low-end
chance over southern Indiana as most of the forcing aloft looks to
remain over the Tennessee Valley.
Precip chances continue into Tuesday, especially in east central
Kentucky, in closer proximity to the boundary and surface reflection
of the upper disturbance. Slightly drier NE flow will serve as a
limiting factor, so will taper to lower POPs and warmer afternoon
temps west of I-65.
Upper shortwave trof currently diving out of the Upper Midwest will
finally kick this moisture out by midnight Tuesday night. This is a
slower progression than previously advertised, but there is good
agreement among the synoptic scale models. Therefore have introduced
a chance POP for Tuesday evening, albeit a low-QPF scenario. After
midnight the high over the Great Lakes should be able to build south
in earnest, resulting in a drying trend with below-normal temps and
falling dewpoints.
.LONG TERM (Wednesday through Monday)...
Issued at 220 PM EDT Mon Jun 17 2013
This period mostly should be quiet. High pressure at the surface
will start off centered over the eastern Great Lakes. Precipitable
waters will fall to under an inch. By week`s end ridging aloft
should allow temperatures to warm back into the 90s, at least at
SDF, but drier surface dewpoints should make this heat wave a little
more bearable than the one last week. The ridge aloft will be
centered over the mid Mississippi river valley Sunday and Monday,
which despite increasing precipitable waters, should keep rain
chances low. Best chance, still slight, should be across our east.
&&
.AVIATION (06Z TAF Update)...
Issued at 112 AM EDT Tue Jun 18 2013
Rather low-confidence continues for the overnight period especially
with regards to potential for low clouds and fog. Widespread shower
activity across western KY will continue to move eastward while
diminishing in coverage. Some light rain will be possible at the
terminals through at least 18/10Z. Cigs and Vsbys look to start off
as VFR, but the guidance suggests some IFR/MVFR cigs developing late
tonight as low clouds build downward. At this time...feel that MVFR
cigs are attainable and will place those into the upcoming
forecast...mainly after 18/08Z through 18/12-14Z. Patchy fog will
also be possible...mainly at KBWG and KLEX. Conditions should
improve a bit after 18/13Z as drier air works in from the NW.
&&
.LMK WATCHES/WARNINGS/ADVISORIES...
IN...NONE.
KY...NONE.
$$
Update...........MJ
Short Term.......RAS
Long Term........RJS
Aviation.........MJ
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
748 PM EDT WED JUN 19 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 00Z TAFS THROUGH 00Z THURSDAY EVENING)
ISSUED AT 748 PM EDT WED JUN 19 2013
VFR CONDITIONS WILL CONTINUE AT KIWD/KCMX/KSAW THRU THE EVENING.
OVERNIGHT...ATTENTION TURNS TO SFC TROF DROPPING S TOWARD THE UPPER
LAKES IN ASSOCIATION WITH SHORTWAVE CURRENTLY PASSING THRU NRN
ONTARIO. SCT SHRA/TSRA ARE CURRENTLY OCCURRING ALONG/AHEAD OF
TROF...AND SOME OF THOSE SHRA MAY HOLD TOGETHER AND AFFECT ALL 3
TERMINALS LATE TONIGHT/THU MORNING. WITH COVERAGE LIMITED...
CONFIDENCE IN SHRA OCCURRING AT EACH TERMINAL IS LOW...SO VCSH WAS
UTILIZED EXCEPT AT KCMX WHICH MAY HAVE A SLIGHTLY BETTER POTENTIAL
OF SHRA. IF SHRA DO OCCUR AT KCMX AND ACROSS LAKE SUPERIOR...
STRATUS/MVFR CIGS AND FOG/MVFR VIS MAY DEVELOP AT KCMX...ESPECIALLY
IF AN E WIND DEVELOPS EARLY IN THE DAY. DURING THE AFTN...DAYTIME
HEATING SHOULD GENERATE SCT SHRA/TSRA ACROSS UPPER MI WITH BETTER
POTENTIAL AT KIWD/KSAW. AGAIN...THERE IS LIMITED CONFIDENCE IN PCPN
ACTUALLY OCCURRING AT A TERMINAL...SO ONLY VCTS WAS INCLUDED IN
FCST. IF SHRA/TSRA OCCUR AT ANY TERMINAL THU...MVFR CONDITIONS WOULD
LIKELY ACCOMPANY PCPN.
&&
.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 MARQUETTE MI
410 PM EDT TUE JUN 18 2013
.SHORT TERM...(THIS EVENING THROUGH WEDNESDAY)
ISSUED AT 409 PM EDT TUE JUN 18 2013
WV IMAGERY AND RUC ANALYSIS INDICATED NW MID/UPPER LEVEL FLOW
THROUGH THE NRN GREAT LAKES BETWEEN A TROUGH OVER QUEBEC AND A RIDGE
FROM THE ROCKIES INTO THE WRN PLAINS. AT THE SFC...A RIDGE EXTENDED
FROM JAMES BAY TO LAKE SUPERIOR. WITH THE DRY AIRMASS OVER THE
REGION (PWAT AROUND 0.50 OR ABOUT 50 PCT OF NORMAL)...A WEAK
SHORTWAVE TROUGH INTO WRN LAKE SUPERIOR ONLY SUPPORTED A PATCH OF
MID/HIGH CLOUDS.
TONIGHT...HIGH PRESSURE WILL CONTINUE TO DOMINATE THE REGION KEEPING
CONDITIONS DRY UNDER MOSTLY CLEAR SKIES. AS THE RIDGE AXIS SLIDES SE
OVERNIGHT...LIGHT RETURN SRLY FLOW WILL RESULT IN A BIT MORE MIXING
ESPECIALLY OVER THE FAR WEST AND ALONG THE LAKE SUPERIOR SHORELINE.
LOOK FOR MIN TEMPS TO RANGE FROM AROUND 40 INLAND TO THE MID
TO UPPER 40S ALONG THE GREAT LAKES SHORELINES.
WEDNESDAY...AS THE RIDGE SLOWLY SLIDES OFF TO THE EAST...SRLY WINDS
WILL INCREASE. 850 MB TEMPS AROUND 10C AND MIXING TO AROUND 800 MB
WILL SUPPORT TEMPS INTO THE MID 70S INLAND...EXCEPT NEAR LAKE
MICHIGAN WHERE ONSHORE FLOW KEEPS READINGS IN THE 60S. ALTHOUGH
MOISTURE WILL ALSO INCREASE SLIGHTLY...THE HIGHER LOW LEVEL THETA-E
AXIS TO SUPPORT SHRA/TSRA WITH WEAK SHRTWVS IN NW FLOW IS EXPECTED
TO REMAIN WEST OF THE CWA.
.LONG TERM...(WEDNESDAY NIGHT THROUGH TUESDAY)
ISSUED AT 409 PM EDT TUE JUN 18 2013
AREA WILL BE UNDER NORTHWEST FLOW ALOFT TO START THE PERIOD AS THE
UPPER GREAT LAKES IS ON THE EASTERN SIDE OF THE RIDGE OVER THE
NORTHERN PLAINS AND UPPER MISSISSIPPI VALLEY. A WEAK SHORTWAVE WILL
BE SLIDING ACROSS NORTHEAST LAKE SUPERIOR ON WEDNESDAY NIGHT...WHILE
A SURFACE TROUGH DROPS SOUTHEAST ACROSS THE CWA DURING THE OVERNIGHT
PERIOD. THERE WILL LIKELY BE SOME SHOWERS AND A FEW THUNDERSTORMS
WITH THIS TROUGH ON WEDNESDAY NIGHT AND WILL FOLLOW A GENERAL
CONSENSUS FOR THE TIMING OF THE POPS AS IT MOVES IN.
THIS FRONT LOOKS TO STALL ACROSS UPPER MICHIGAN ON THURSDAY AND
WILL COMBINE WITH DEVELOPING LAKE BREEZES TO PRODUCE AFTERNOON
SHOWERS AND THUNDERSTORMS. THE STRENGTH OF THESE THUNDERSTORMS WILL
DEPEND ON THE AMOUNT OF DIURNAL HEATING...INCREASING SOUTHERLY
FLOW WITH A DEVELOPING WARM FRONT ON THE BOUNDARY...AND THE ARRIVAL
OF THE ANOTHER WEAK SHORTWAVE DURING THE LATE AFTERNOON AND
EVENING. ML CAPE VALUES OF 500-1000 J/KG OVER THE WESTERN 2/3RDS
OF THE CWA AND 0-6KM BULK SHEAR VALUES AROUND 30KTS SUPPORTS
THUNDERSTORMS AND SOME TILTING OF THE UPDRAFTS. HEAVY RAIN AND
SMALL HAIL WILL BE THE PRIMARY THREATS...AS NCAPE VALUES AROUND .1
SHOULD KEEP ANY HAIL FROM GROWING TOO LARGE. WILL CONTINUE TO
HIGHLIGHT THE HIGHEST POPS OVER THE INTERIOR WEST/CENTRAL...CLOSEST
TO LAKE SUPERIOR LAKE BREEZE AND THEN FOLLOW THE STORM MOTION TO THE
SOUTHEAST.
THURSDAY NIGHT THROUGH THE WEEKEND IS SHAPING UP TO BE A FAIRLY
ACTIVE PATTERN FOR THUNDERSTORMS IN THE UPPER MISSISSIPPI VALLEY
AND UPPER GREAT LAKES REGION. THIS IS DUE TO THE UPPER RIDGE
GRADUALLY SHIFTING EAST INTO THE UPPER GREAT LAKES.
MEANWHILE...WEAK SURFACE LOW WILL REMAIN FAIRLY STATIONARY OVER THE
CENTRAL/NORTHERN PLAINS. FROM THIS LOW...A WARM FRONT WILL LOOKS TO
SETUP FROM THE STALLED TROUGH ON THURSDAY AND REMAIN LOCATED AROUND
THE UPPER GREAT LAKES REGION THROUGH THE WEEKEND. LOOKING AT THIS
LARGE SCALE PATTERN...IT IS VERY CONDUCIVE PERIODS OF SHOWERS AND
POTENTIALLY STRONG THUNDERSTORMS. BUT TRYING TO PIN DOWN THE
EXACT LOCATION AND TIMING IS DIFFICULT DUE TO THE VARIABILITY OF THE
SHORTWAVES AND POSITION OF THE WARM FRONT. INSTABILITY WILL
GRADUALLY GROW FROM FRIDAY INTO THE WEEKEND...AS PERSISTENT
SOUTHWESTERLY FLOW AHEAD OF THE LOW PULLS PLENTY OF GULF MOISTURE
INTO THE AREA. USING ML CAPE VALUES TO REMOVE SOME OF THE LOW
LEVEL MOIST BIASES IN THE MODELS FOR FRIDAY INTO THE WEEKEND...THERE
ARE STILL SOME DECENT VALUES FOR U.P. STANDARDS. FRIDAY THEY LOOK TO
PEAK IN THE 750-1500 J/KG RANGE OVER THE WEST AND THEN GROW TO
1500-2500 J/KG FOR SAT/SUN DEPENDING ON THE MODEL. THE GFS IS THE
MOST AGGRESSIVE ON THE NORTHWARD EXTENT OF THE WARM FRONT...WHILE
THE GEM/ECMWF TRY TO KEEP THE FRONT A TOUCH SOUTH OF THE AREA. IT
WILL PROBABLY BE A VARIETY OF THUNDERSTORM TYPES DURING THAT PERIOD.
CONVECTIVE COMPLEXES MOVING EAST /VIA FORWARD PROP CORFIDI VECTORS/
AROUND THE RIDGE WILL LIKELY BE THE MAIN THREAT...BUT WITH THE
INSTABILITY PRESENT AND LIMITED INHIBITION...DIURNAL THUNDERSTORMS
WILL ALSO BE POSSIBLE. THE ONLY CONCERNS WOULD BE IF THE RIDGE AND
WARM FRONT BUILD FAR ENOUGH NORTH TO SLIDE MOST OF THE THUNDERSTORM
COMPLEXES NORTH OF UPPER MICHIGAN OR THE MORE LIKELY SCENARIO OF IT
BECOMING HUNG UP SOUTH OF THE AREA /ESPECIALLY AS CONVECTION HOLDS
THEM SOUTH/. WITH THE GROWING CONFIDENCE...WILL ADD A MENTION OF
STRONG THUNDERSTORMS FOR THE WEEKEND IN BOTH THE HWO AND EHWO. HEAVY
RAIN IS ALSO POSSIBLE DURING THIS PERIOD WITH THE THUNDERSTORMS...AS
PWAT VALUES RISE ABOVE 1.5 INCHES WHICH IS WELL ABOVE THE 75TH
PERCENTILE FOR CLIMATOLOGY FOR THIS AREA.
IT WILL BE PRETTY HUMID FOR FRIDAY INTO THE WEEKEND /DEWPOINTS IN
THE UPPER 50S AND 60S/ AND THE TEMPERATURES WILL DEPEND ON THE
POSITIONING OF THE WARM FRONT. WILL CONTINUE TO SHOW TEMPS IN THE
MID 70S TO LOWER 80S FOR MOST LOCATIONS...WITH THE WARMEST VALUES
NEAR THE WISCONSIN BORDER. IF THE GFS ENDS UP BEING CORRECT...WOULD
HAVE TO BUMP TEMPS UP WELL INTO THE 80S FOR THE END OF THE WEEKEND.
UNCERTAINTY REALLY GROWS HEADING INTO MONDAY/TUESDAY...AS A LOT
DEPENDS ON THE WEEKEND WEATHER. THE GENERAL IDEA FROM THE MODELS IS
THAT THE RIDGE BREAKS DOWN AND THE AREA WILL BE UNDER ZONAL FLOW
ALOFT. THIS WILL CONTINUE TO BRING WAVES ACROSS THE AREA AND KEEP
THE THUNDERSTORM POTENTIAL IN PLACE FOR THAT PERIOD. AT THIS
TIME...MODELS ARE INDICATING A COLD FRONT DROPPING SOUTH OUT OF
CANADA ON WEDNESDAY...WHICH MAY BRING AN END TO THE WARM/HUMID
WEATHER.
FINALLY...WILL CONTINUE TO MENTION PATCHY FOG DEVELOPING ON LAKE
SUPERIOR ON WEDNESDAY NIGHT AND THEN CONTINUING INTO EARLY NEXT
WEEK. WILL LIKELY NEED TO EXPAND IT TO AREAS OR EVEN DENSE FOG AS IT
NEARS. ALSO...ADDED A MENTION OF FOG OVER LAKE MICHIGAN NEARSHORE
AREAS STARTING LATE THURSDAY NIGHT AS THE PRECIPITATION AND HIGHER
DEWPOINTS START TO AFFECT THAT AREA.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON)
ISSUED AT 133 PM EDT TUE JUN 18 2013
WITH HIGH PRESSURE IN CONTROL...VFR CONDITIONS EXPECTED TO CONTINUE
THROUGH THE PERIOD.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 409 PM EDT TUE JUN 18 2013
NO SIGNIFICANT PRESSURE CHANGES THROUGH THE PERIOD WILL RESULT IN
WINDS BELOW 25 KT...OUTSIDE OF ANY THUNDERSTORMS WHICH ARE POSSIBLE
FROM WEDNESDAY NIGHT THROUGH SUNDAY. INCREASING LOW LEVEL MOISTURE
INTO THE REGION FROM AFTER WEDNESDAY...WILL RESULT IN AREAS OF
FOG...POSSIBLY DENSE AT TIMES.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...JLB
LONG TERM...SRF
AVIATION...JLB
MARINE...JLB
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
119 AM EDT TUE JUN 18 2013
.SHORT TERM...(THIS EVENING THROUGH TUESDAY)
ISSUED AT 400 PM EDT MON JUN 17 2013
WV IMAGERY AND RUC ANALYSIS INDICATED A MID/UPPER LEVEL LOW OVER NRN
QUEBEC RESULTING IN WNW FLOW THROUGH GREAT LAKES. AT THE SFC...HIGH
PRES OVER NRN ONTARIO AND NRN MANITOBA WAS BUILDING SOUTHWARD INTO
THE NRN LAKES. WEAK 850-700 MB FGEN SUPPORTED A BAND OF DIMINISHING
LIGHT RAIN SHOWERS OR SPRINKLES OVER S CNTRL UPPER MI.
OTHERWISE...THE LOW CLOUDS OVER NRN UPPER MI HAD DISSIPATED LEAVING
MAINLY JUST SCT-BKN MID CLOUDS. FARTHER SOUTH...A WEAK SHORTWAVE
TROUGH INTO NRN WI SUPPORTED SCT TSRA OVER N CNTRL WI IN AREA WHERE
SFC HEATING HAD PUSHED MLCAPES INTO THE 500-1000 J/KG RANGE. MLCAPE
VALUES AND TSRA MOTION SUGGESTS THE TSRA WILL REMAIN SOUTH OF THE
CWA.
TONIGHT...THE MODELS WERE CONSISTENT IN BRINGING CLEARING ACROSS THE
REGION. WITH PWAT VALUES FALLING TO NEAR 0.30 INCH OVER THE WEST(35
PCT OR NORMAL) FAVORABLE RADIATIONAL COOLING CONDITIONS WILL ALLOW
TEMPS TO DROP TO NEAR THE LOWER END OF GUIDANCE. UPSTREAM OBS FROM
LAST NIGHT N OF LAKE SUPERIOR SUGGEST THAT TEMPS COULD FALL INTO THE
33F TO 36F RANGE OVER FAVORED COLDER LOCATIONS OVER THE INTERIOR
WEST HALF. SO...SOME PATCHY FROST WILL BE POSSIBLE. WITH THE LIGHT
RAIN THIS AFTERNOON INTO PORTION OF THE SOUTHWEST AND DELAYED
CLEARING/MIXING...LOW LEVEL MOISTURE MAY BE SLIGHTLY HIGHER THAN
EARLIER EXPECTED. SO...WAS NOT AS CONFIDENT IN MORE WIDESPREAD FROST
THAT WOULD REQUIRE AN ADVISORY.
TUE...SUNSHINE AND MIXING TO AROUND 800 MB SUPPORTS MAX TEMPS INTO
THE LOWER 70S INLAND AND DEWPOINTS INTO THE MID 30S RESULTING IN RH
VALUES TO NEAR 25 PCT. WITH HIGH PRESSURE AND LIGHT WINDS OVER THE
REGION...LAKE BREEZES WILL KEEP TEMPS IN THE 60S CLOSER TO THE GREAT
LAKES.
.LONG TERM...(TUESDAY NIGHT THROUGH MONDAY)
ISSUED AT 400 PM EDT MON JUN 17 2013
THE START OF THE LONG TERM PERIOD WILL BE QUIET...AS THE AREA IS
UNDER NORTHWEST FLOW ALOFT AND A DRY SURFACE OVER THE UPPER GREAT
LAKES REGION. THIS WILL PRODUCE CLEAR SKIES AND A PLEASANT JUNE
NIGHT ACROSS THE AREA. AS THE HIGH SHIFTS SOUTHEAST INTO THE LOWER
GREAT LAKES ON WEDNESDAY...SOUTHWESTERLY LOW LEVEL FLOW WILL BE ON
THE INCREASE AND PUSH 850MB TEMPS UP TO 10C. WITH DEEP MIXING TO
800-750MB...WOULD EXPECT HIGHS TO RISE INTO THE MID-UPPER 70S. IN
ADDITION...WITH THE DEEP MIXING AND DRY LOW LEVEL AIR...HAVE
FOLLOWED MIXED LAYER DEWPOINTS FOR INTERIOR LOCATIONS /UPPER 30S TO
MID 40S/...LOWEST OVER THE EAST. THIS PRODUCES MINIMUM RH VALUES
AROUND 30 PERCENT OVER THE EAST. WIND SHOULDN/T BE TOO GUSTY THROUGH
THE FIRST PART OF WEDNESDAY...BUT WITH THE FLOW INCREASING THROUGH
THE DAY THERE COULD BE SOME GUSTS TO 15-20MPH IN THE MID-LATE
AFTERNOON. THIS COULD END UP PRODUCING MARGINAL FIRE WX CONCERNS FOR
THE CENTRAL/EASTERN UPPER MICHIGAN WHERE PRECIPITATION IS A LITTLE
BELOW NORMAL OVER THE LAST 30 DAYS.
ATTENTION FOR THE LONG TERM THEN TURNS TO A SERIES OF SHORTWAVES
THAT WILL BE AFFECTING THE AREA FOR THE WEDNESDAY NIGHT INTO THE
WEEKEND. THE FIRST WAVE WILL BE DROPPING SOUTHEAST ACROSS NORTHERN
LAKE SUPERIOR ON WEDNESDAY NIGHT...WITH AN ASSOCIATED WEAK SURFACE
COLD FRONT/TROUGH PUSHING THROUGH. WITH IT BEING NEAR THE MN
ARROWHEAD AROUND PEAK HEATING ON WEDNESDAY...THERE WILL LIKELY BE
SHOWER/THUNDERSTORM DEVELOPMENT THERE AND NORTHWEST OF LAKE SUPERIOR
IN ONTARIO. WITH THE FORECASTED STORM MOTION...THESE
SHOWERS/THUNDERSTORMS WILL MOVE SOUTHEAST INTO WESTERN LAKE SUPERIOR
ON WEDNESDAY AFTERNOON AND WILL CONTINUE TO MENTION SLIGHT CHANCE
POPS THERE. QUESTION IS HOW MUCH THEY WILL DIMINISH AS DIURNAL
HEATING IS LOST AND IT RUNS INTO THE EXISTING DRY AIR FROM THE HIGH.
THE BEST FORCING/MOISTURE IS CLOSER TO THE SHORTWAVE MOVING ACROSS
NORTHERN LAKE SUPERIOR...SO WILL FOLLOW THAT IDEA FOR THE HIGHEST
POPS AND THEN DIMINISH THE REST AS THEY DROP SOUTHEAST THROUGH THE
NIGHT.
FRONT LOOKS TO STALL OVER THE AREA ON THURSDAY. DIURNAL
HEATING WILL COMBINE WITH WEAK LAKE BREEZES TO AID CONVECTION
DEVELOPMENT. THINK THE BEST INTERACTION WITH THE CONVERGENCE
AND INSTABILITY /ML CAPE VALUES TO AROUND 1000 J/KG/ WILL BE OVER
THE CENTRAL PORTIONS OF THE CWA. HAVE TRENDED POPS UP TO HIGH
CHANCE AND LOW LIKELY VALUES WITH THE CONSISTENCY IN THE MODELS.
0-6KM BULK SHEAR VALUES ARE ON THE MARGINAL SIDE /25-30KTS/ AND
WITH CAPE FAIRLY TALL/SKINNY...WOULD THINK HEAVY RAIN WOULD BE THE
BIGGEST CONCERN WITH RELATIVELY SLOW STORM MOTIONS OF 20KTS
ALTHOUGH SMALL HAIL CAN/T BE RULED OUT.
MEANWHILE...UPPER RIDGE IN THE SOUTHERN STREAM WILL BUILD INTO THE
NORTHERN PLAINS ON THURSDAY AND THE FORECAST FOR THURSDAY NIGHT
INTO THE WEEKEND WILL DEPEND ON A SERIES OF SHORTWAVES ROUNDING THE
RIDGE AND SLIDING THROUGH THE CWA. THIS MAKES PINNING DOWN POPS A
LITTLE DIFFICULT AS THEY WILL DEPEND ON CONVECTION DEVELOPING
UPSTREAM AND MOVING THROUGH. AT THIS POINT...IT SEEMS LIKE THE
WAVES WILL COME LATE THURSDAY NIGHT INTO FRIDAY...LATE FRIDAY NIGHT
THROUGH SATURDAY EVENING...AND AGAIN ON SUNDAY. WILL HIGHLIGHT
THOSE PERIODS FOR THE HIGHEST POPS. INSTABILITY WILL BE ON THE
INCREASE THROUGH THAT PERIOD...SO THUNDERSTORMS ARE POSSIBLE WITH
EACH OF THE WAVE. SEVERE THREAT WILL LARGELY DEPEND ON WHERE THE
WARM FRONT WILL LINE UP ON THE EAST SIDE OF THE NEARLY STATIONARY
LOW IN THE NORTHERN PLAINS AND THE EXACT LOCATION OF THE
SHORTWAVES. WITH THE SOURCE REGION FOR THE THUNDERSTORMS GETTING
CLOSER INTO THE WEEKEND...WOULD THINK THE SEVERE THREAT WILL BE ON
THE RISE. THIS IS ESPECIALLY TRUE FOR THE BEGINNING OF THE
WEEKEND...AS INSTABILITY BEGINS TO PEAK AND THE OVERALL PATTERN
LOOKS CONDUCIVE FOR AN MCS FORMING IN THE UPPER MISSISSIPPI VALLEY
AND ROLLING THROUGH THE UPPER GREAT LAKES. CIPS WARM SEASON ANALOGS
FROM THE 12Z GFS ALSO SHOW AN INCREASING SEVERE THREAT TOWARDS
SATURDAY...SO IT WILL DEFINITELY BE SOMETHING TO WATCH OVER THE
COMING DAYS.
THE RIDGE LOOKS TO BREAK DOWN BY THE SECOND HALF OF THE WEEKEND AND
THE AREA WILL COME UNDER MORE ZONAL TO START THE NEXT WORK WEEK.
CONFIDENCE REALLY DIMINISHES FOR THIS PERIOD AS IT WILL ALL DEPEND
ON SMALLER SCALE FEATURES. IN GENERAL...IT APPEARS THE BOUNDARY
THAT WILL BRING THE CONVECTION TO THE AREA FOR THE END OF THIS WEEK
WILL SAG SOUTH AND FOCUS THE BETTER OPPORTUNITY FOR CONVECTION
SOUTH OF THE AREA.
WARM AND HUMID CONDITIONS ARE EXPECTED THURSDAY INTO THE
WEEKEND...WITH DEWPOINTS RISING INTO THE 60S. ADDED PATCHY FOG OVER
LAKE SUPERIOR FOR WEDNESDAY NIGHT THROUGH MONDAY WITH THE EXPECTED
PRECIPITATION AND HUMID CONDITIONS. MAY NEED TO INCREASE IT IN
COVERAGE IN THE FUTURE AND ALSO EXPAND IT INTO LAKE MICHIGAN.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT)
ISSUED AT 118 AM EDT TUE JUN 18 2013
WITH HIGH PRESSURE IN CONTROL...VFR CONDITIONS ARE EXPECTED TO
CONTINUE THROUGH THE PERIOD. &&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 400 PM EDT MON JUN 17 2013
WINDS ARE EXPECTED TO STAY BELOW 20KTS THROUGH THE PERIOD. HIGH
PRESSURE BUILDING OVER THE UPPER GREAT LAKES TONIGHT WILL REMAIN
THROUGH WEDNESDAY. A WEAK TROUGH WILL THEN APPROACH THE AREA
FROM THE NORTHWEST FOR THURSDAY.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...JLB
LONG TERM...SRF
AVIATION...07
MARINE...JLB
AREA FORECAST DISCUSSION
NWS KANSAS CITY/PLEASANT HILL MO
1241 PM CDT Tue Jun 18 2013
.UPDATE...
Issued at 924 AM CDT TUE JUN 18 2013
MCv over central NE, shortwave sliding southeast through IA and a
weak frontal boundary moving south through the CWA has muddied the
water for the next 12 hours. All models except the latest RAP are
unable to handle the meso feature in NE. However, the 12z NAM and
even the 06z GFS do develop afternoon convection along the frontal
boundary from northeast KS through west central MO. given the
proximity of the MCV moving into a more unstable airmass...the 12z
NAM forecasts afternoon MUCAPES of 2000+ J/kg along and south of this
front believe it prudent as a starting point to insert low chance PoPs
over the west central counties after 20Z. May need to continue chance
PoPs into the evening hours across the southern CWA but will assess
that potential later.
The more widely scattered convection across northern MO and southern
IA is expected to dissipate this morning as it slides across northern MO.
&&
.SHORT TERM...(Today through Wednesday)
Issued at 306 AM CDT TUE JUN 18 2013
With upper ridging to the west and northwest flow overhead,
conditions today should be generally dry while temperatures stay
close to average. A weak shortwave in this flow pattern will drop out
of Minnesota into the Corn Belt through the day, clipping northeast
Missouri in the process. Moisture and instability will be
lacking over this area thanks to surface ridging building in from the
north. Therefore the only effects from this system should be a few
high clouds and possibly some daytime cumulus. Some short-range
models are also bringing precipitation out of western Nebraska into
northwest Missouri later this morning. This activity should have a
tough time surviving as far east as MO due to dry air in place, so
stayed with a dry forecast for all areas through the afternoon.
Upper ridge to the west will flatten slightly on Wednesday and shift
its axis westward into the Plains. This will likely allow a weak vort
max to drop east-southeast toward western MO Wednesday and Wednesday
evening with an attendant threat for thunderstorms, especially across
KS and western MO. An increase in moisture should provide weak to
moderate instability for this feature to work with, but weak winds
throughout the troposphere will be unsupportive of strong or severe
storms, at least through Wednesday night.
.LONG TERM...(Thursday through Monday)
Issued at 306 AM CDT TUE JUN 18 2013
Thursday should bring the last real chance for precipitation during
the long range forecast period as a shortwave trough drops through
northern Missouri. Strong shear and decent instability could promote
a stronger storm or two, but increasing CIN and a lack of surface
focus may make storms hard to come by, especially during the
afternoon hours.
After Thursday a ridge will build into the eastern Plains, keeping
most convection off to the north. Precipitation chances will be
limited to the propagation of ongoing storms into the region, which
is hinted at by a few model solutions late Thursday night through
Friday morning; otherwise, the end of the week through the weekend
should be mainly dry. Ridging will also allow temperatures to warm
into the 90s for Friday through Sunday, while southerly winds and
decent Gulf moisture draw upper 60s to 70s dewpoints into the
region. These conditions will result in heat indices nearing 100
degrees in the afternoon hours, and will need to be monitored for
possible heat headlines in the future.
Most models indicate a gradual flattening of the ridge from late
Sunday into Monday as deep low pressure lifts across the Canadian
border. This shift in the pattern may allow for slightly better
chances of precipitation going into early next week, as well as
slightly cooler temperatures.
&&
.AVIATION...(For the 18Z TAFS through 18Z Wednesday Afternoon)
Issued at 1233 PM CDT TUE JUN 18 2013
Scattered convection will move across northwest and west central MO
and eastern KS this afternoon in advance of a shortwave spawned by
last nights Central High Plains convection. A weak cold front
oriented northwest to southeast will stretch across northeast KS and
west central MO and help focus and steer these showers and
thunderstorms. Inspection of NAM Bufr soundings shows a relatively
dry sub-cloud region suggesting potential for strong and gusty winds
should any convection form. Will use VCTS in the forecast with the
likelihood of updating the forecast and inserting strong winds should
the convection become better organized. Activity should be out of the
terminals by early evening. Thereafter, VFR conditions will exist.
&&
.EAX WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
MO...NONE.
&&
$$
UPDATE...MJ
SHORT TERM...Hawblitzel
LONG TERM...Laflin
AVIATION...MJ
AREA FORECAST DISCUSSION
NWS KANSAS CITY/PLEASANT HILL MO
931 AM CDT Tue Jun 18 2013
.UPDATE...
Issued at 924 AM CDT TUE JUN 18 2013
MCv over central NE, shortwave sliding southeast through IA and a
weak frontal boundary moving south through the CWA has muddied the
water for the next 12 hours. All models except the latest RAP are
unable to handle the meso feature in NE. However, the 12z NAM and
even the 06z GFS do develop afternoon convection along the frontal
boundary from northeast KS through west central MO. given the
proximity of the MCV moving into a more unstable airmass...the 12z
NAM forecasts afternoon MUCAPES of 2000+ J/kg along and south of this
front believe it prudent as a starting point to insert low chance PoPs
over the west central counties after 20Z. May need to continue chance
PoPs into the evenign hours across the southern CWA but will assess
that potential later.
The more widely scattered convection across northern MO and southern
IA is expected to dissipate this morning as it slides across northern MO.
&&
.SHORT TERM...(Today through Wednesday)
Issued at 306 AM CDT TUE JUN 18 2013
With upper ridging to the west and northwest flow overhead,
conditions today should be generally dry while temperatures stay
close to average. A weak shortwave in this flow pattern will drop out
of Minnesota into the Corn Belt through the day, clipping northeast
Missouri in the process. Moisture and instability will be
lacking over this area thanks to surface ridging building in from the
north. Therefore the only effects from this system should be a few
high clouds and possibly some daytime cumulus. Some short-range
models are also bringing precipitation out of western Nebraska into
northwest Missouri later this morning. This activity should have a
tough time surviving as far east as MO due to dry air in place, so
stayed with a dry forecast for all areas through the afternoon.
Upper ridge to the west will flatten slightly on Wednesday and shift
its axis westward into the Plains. This will likely allow a weak vort
max to drop east-southeast toward western MO Wednesday and Wednesday
evening with an attendant threat for thunderstorms, especially across
KS and western MO. An increase in moisture should provide weak to
moderate instability for this feature to work with, but weak winds
throughout the troposphere will be unsupportive of strong or severe
storms, at least through Wednesday night.
.LONG TERM...(Thursday through Monday)
Issued at 306 AM CDT TUE JUN 18 2013
Thursday should bring the last real chance for precipitation during
the long range forecast period as a shortwave trough drops through
northern Missouri. Strong shear and decent instability could promote
a stronger storm or two, but increasing CIN and a lack of surface
focus may make storms hard to come by, especially during the
afternoon hours.
After Thursday a ridge will build into the eastern Plains, keeping
most convection off to the north. Precipitation chances will be
limited to the propagation of ongoing storms into the region, which
is hinted at by a few model solutions late Thursday night through
Friday morning; otherwise, the end of the week through the weekend
should be mainly dry. Ridging will also allow temperatures to warm
into the 90s for Friday through Sunday, while southerly winds and
decent Gulf moisture draw upper 60s to 70s dewpoints into the
region. These conditions will result in heat indices nearing 100
degrees in the afternoon hours, and will need to be monitored for
possible heat headlines in the future.
Most models indicate a gradual flattening of the ridge from late
Sunday into Monday as deep low pressure lifts across the Canadian
border. This shift in the pattern may allow for slightly better
chances of precipitation going into early next week, as well as
slightly cooler temperatures.
&&
.AVIATION...(For the 12Z TAFS through 12Z Wednesday Morning)
Issued at 555 AM CDT TUE JUN 18 2013
Showers and a few weak storms over NE/IA are encountering a dry
airmass over northern MO and appear unlikely to affect the STJ or KC
terminals. Otherwise expect winds to become northerly or NNE-erly in
the next couple of hours, slowly veering through the afternoon and
evening.
&&
.EAX WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
MO...NONE.
&&
$$
UPDATE...MJ
SHORT TERM...Hawblitzel
LONG TERM...Laflin
AVIATION...Hawblitzel
AREA FORECAST DISCUSSION
NWS GLASGOW MT
753 PM MDT WED JUN 19 2013
.SHORT TERM...FOR NORTHEAST MONTANA...TONIGHT THROUGH FRIDAY...
UPDATE...CENTRAL MONTANA CONVECTION CONTINUES TO MOVE NORTH...SOME
CELLS HAVE STARTED IN PETROLEUM COUNTY THIS EVENING. WATER VAPOR
IS SHOWING DIFULENT FLOW ALOFT WITH A WAVE MOVING INTO THE REGION
FROM THE SOUTH. THE HRRR IS DOING OK TONIGHT AND SUPPORTS CURRENT
THINKING AND NATIONAL CENTER THINKING THAT A COMPLEX OF
THUNDERSTORMS IS MOST LIKELY FOR NORTHEAST MONTANA FOR THE LATE
EVENING HOURS INTO THE EARLY OVERNIGHT HOURS. THE LEADING EDGE OF
THIS COULD PRODUCE VERY GUSTY WINDS...AND THEN RAIN HEAVY AT
TIMES. THIS CONTINUES TO SUPPORT THE PHILLIPS COUNTY FLASH FLOOD
WATCH AND ZONE WORDING. DID TWEAK ELEMENTS AROUND TO BEST FIT THE
CURRENT SITUATION. PROTON
A CLOSED UPPER LEVEL LOW CONTINUES TO SPIN ACROSS THE PACIFIC
NORTHWEST. SHORTWAVE ENERGY PIVOTING AROUND THIS CLOSED LOW IS
PROPAGATING THROUGH SOUTHWEST FLOW ALOFT AND WILL BE RESPONSIBLE
FOR THE DEVELOPMENT OF SHOWERS AND THUNDERSTORMS THIS EVENING.
PLENTY OF CAPE EXISTS BUT WIND SHEAR PROFILES ARE NOT ALL THAT
IMPRESSIVE. THERE IS GOOD DIRECTIONAL SHEAR BUT SPEED SHEAR IS
LACKING. GIVEN CAPE/SHEAR PROFILES...WILL EXPECT DEVELOPING
SUPERCELLS TO FORM INTO LINE SEGMENTS THIS EVENING AS THEY PUSH
FROM THE SOUTHWESTERN ZONES THIS EVENING NORTHEASTWARD THROUGH THE
OVERNIGHT. TEMPERATURES THIS AFTERNOON HAVE BEEN WELL INTO THE
80S...SURFACE DEW POINTS HAVE BEEN HOVERING AROUND 60
DEGREES...AND SO THERE IS PLENTY OF WARM...MOIST...LOW LEVEL AIR.
STEEP MIDLEVEL LAPSE RATES ARE ALSO EVIDENT IN NAM BUFKIT
SOUNDINGS.
CONSIDERING ALL OF THIS...A FEW STORMS MAY BECOME SEVERE WITH
LARGE HAIL AND DAMAGING WINDS. HOWEVER...THE PRIMARY THREAT AT
THIS POINT WILL BE THE HEAVY RAINFALL. NAM BUFKIT SOUNDINGS SHOW
PRECIPITABLE WATER VALUES BETWEEN AN INCH AND AN INCH AND A HALF.
THE LATEST NAM/GFS/ECMWF SHOWS THE POTENTIAL FOR HEAVY RAINFALL
ACROSS THE CWA...WITH THE BEST AGREEMENT IN PHILLIPS AND NORTHERN
VALLEY COUNTIES. THIS IS FURTHER SUPPORTED BY THE SREF. THE HRRR
MODEL HAS ALSO BEEN INSISTING ON DEVELOPING CONVECTION AROUND 00Z
IN THE SOUTHWEST AND HAVING IT FORM INTO A LINE AS IT PUSHES
NORTHEAST OVERNIGHT. THEREFORE...SOME OF THE FAR NORTHEASTERN
ZONES MAY ACTUALLY STAY DRY UNTIL MORNING. GIVEN POTENTIAL FOR
EXCESSIVE RAINFALL RATES TO OCCUR OVER A SHORT DURATION...WILL
HOIST A FLASH FLOOD WATCH FOR PHILLIPS COUNTY. WILL OPT TO LEAVE
OUT NORTHERN VALLEY AT THIS POINT BECAUSE BEST AGREEMENT IS ON
RAINFALL FURTHER WEST BUT THE NEXT SHIFT WILL HAVE TO MONITOR
CLOSELY. A LAKE WIND ADVISORY REMAINS IN EFFECT UNTIL MIDNIGHT AND
GIVEN WINDS ALONG FORT PECK LAKE RECENTLY GUSTING ABOVE 40
MPH...THIS HEADLINE LOOKS GOOD.
SHOWERS AND THUNDERSTORMS MAY LINGER IN THE NORTHEASTERN ZONES ON
THURSDAY. OTHERWISE BEHIND THE COLD FRONTAL PASSAGE EXPECT MUCH
COOLER TEMPERATURES FOR AFTERNOON HIGHS. THE UPPER LOW ACROSS THE
PACIFIC NORTHWEST WILL REMAIN FIRMLY IN PLACE THROUGH FRIDAY
THOUGH AS ADDITIONAL SHORTWAVE ENERGY PUSHES INTO THE FORECAST
REGION. THUS...AFTER A BREAK IN BETWEEN SYSTEMS ON THURSDAY
NIGHT...INCREASED POPS AGAIN ON FRIDAY WITH THE NEXT APPROACHING
SHORTWAVE FEATURE. MALIAWCO
.LONG TERM...FRIDAY NIGHT THROUGH WEDNESDAY...
GOING FORECAST IN GOOD SHAPE BUT DID TWEAK UP THE POPS/WEATHER FOR
LATE SATURDAY INTO EARLY SUNDAY AS SHOWERS SEEM TO BE A PRETTY GOOD
BET WITH THE UPPER LOW IN PROXIMITY. JAMBA
PREVIOUS DISCUSSION...
LONG TERM FORECAST PERIOD BEGINS AS THE MAIN ENERGY FROM THE
MEANDERING LOW PRESSURE SYSTEM OVER THE PACIFIC NORTHWEST AND
NORTHERN ROCKIES REGIONS FINALLY KICKS OUT THROUGH THE EASTERN
SLOPES OF THE ROCKY MOUNTAINS AND THEN THE NORTHERN HIGH PLAINS
THROUGH THE REMAINDER OF THE WEEKEND.
EXPECT THIS WEEKEND TO BE FAIRLY WET WITH A LITTLE UNCERTAINTY
REGARDING PRECIPITATION AMOUNTS AS THE 00Z RUN OF THE EC HAS YET
TO COME IN. SOME COMPARISONS SHOW SIGNIFICANT DISCREPANCIES TO THE
POINT OF BEING EXACT OPPOSITES. WOULD HAVE TO GIVE IT LESS THAN
AVERAGE FORECAST CONFIDENCE AT BEST. TRIED TO INCREASE POPS IN A
BROAD-BRUSHED AND BLENDED KIND OF WAY WHERE BEST MODEL AGREEMENT
IF ANY WAS TO BE FOUND...THEN REDUCED POPS SIMILARLY WHERE MODELS
AGREED IN THE LACK THEREOF.
THERE SEEMS TO BE A BRIEF SHORT WAVE RIDGE FROM SUNDAY THROUGH
MONDAY MORNING WHICH SHOULD BRING AN END TO THE WET PERIOD FROM
THE WEEKEND.
NORTHEAST MONTANA THEN FINDS ITSELF IN A PERSISTENT ZONAL OR
SLIGHTLY SOUTHWESTERN FLOW ALOFT WITH SOME SMALL SCALE EMBEDDED
DISTURBANCES. ALTHOUGH THE MODELS ARE TRENDING A BIT DRIER TOWARD
THE END OF THE FORECAST PERIOD AS THE GULF OF ALASKA LOW BATTLES
AGAINST THE FOUR CORNERS HIGH. BMICKELSON
&&
.AVIATION...
VFR CONDITIONS ARE EXPECTED BUT MVFR CONDITIONS ARE POSSIBLE
STARTING AT GLASGOW THIS EVENING. EVENING SHOWERS AND
THUNDERSTORMS WILL CONTINUE OVERNIGHT...MOST OF THEM ARE EXPECTED
TO IMPACT LOCATIONS ALONG AND NORTH OF HIGHWAY 2 WITH HEAVY RAIN
POSSIBILITIES.
SOUTHEAST WINDS WILL DECREASE TONIGHT AS A COLD FRONT ARRIVES FROM
THE WEST/SOUTHWEST. EXPECT WEST WINDS ON THURSDAY AT ABOUT 10 TO
20 KTS. JAMBA
&&
.GLASGOW WATCHES/WARNINGS/ADVISORIES...
FLASH FLOOD WATCH UNTIL 6 AM MDT THURSDAY FOR CENTRAL AND
SOUTHEAST PHILLIPS...NORTHERN PHILLIPS...SOUTHWEST PHILLIPS.
LAKE WIND ADVISORY UNTIL MIDNIGHT MDT TONIGHT FOR FORT PECK LAKE
FOR CENTRAL AND SOUTHEAST PHILLIPS...CENTRAL AND SOUTHERN
VALLEY...GARFIELD...MCCONE...PETROLEUM.
&&
$$
WEATHER.GOV/GLASGOW
AREA FORECAST DISCUSSION
NWS BILLINGS MT
300 PM MDT TUE JUN 18 2013
.SHORT TERM...VALID FOR WED AND THU...
CONVECTION WAS OCCURRING OVER SOUTHERN PARTS OF THE AREA PER
RADAR IMAGERY THIS AFTERNOON. LATEST RAP ANALYSIS SHOWED SURFACE
CAPES OF 1500-2500 J/KG OVER SE MT. ELSEWHERE...CAPES WERE IN THE
700 TO 2000 J/KG RANGE...PRETTY VARIABLE ACROSS THE FORECAST AREA.
SHEAR WAS GENERALLY WEAK...HOWEVER VALUES WERE 30 TO 35 KT OVER SE
MT...SO BEST CHANCES OF ANY STRONG TO SEVERE STORMS WILL BE OVER
THE SE. WILL CONTINUE TO MENTION SMALL HAIL/GUSTY WINDS ACROSS THE
AREA DUE TO THE CAPES AND INVERTED-V SOUNDINGS. HAD POPS ACROSS
THE AREA THIS EVENING...THEN ACTIVITY SHOULD DISSIPATE AFTER
MIDNIGHT MDT WITH LOSS OF HEATING.
JET ENERGY WILL ROTATE AROUND THE UPPER LOW OVER THE PACIFIC
NW...CAUSING IT TO PROGRESS E WITH TIME. WILL HAVE INCREASING
Q-VECTOR CONVERGENCE OVER THE AREA STARTING ON WED...AS SHORTWAVES
CONTINUE MOVING INTO THE REGION. UPPER DIFLUENCE WILL CONTINUE TO
CONTRIBUTE TO LIFT ON WED. BOTH THE GFS AND WRF HAD LARGE CAPES
2000-3000 J/KG OVER THE FAR EASTERN AND NORTHERN PARTS OF THE
AREA WED AND WED EVENING...AS WELL AS INCREASING SHEAR OVER THE
AREA FROM W TO E. HOWEVER...DRY AIR OVER THE FOUR CORNERS REGION
THIS AFTERNOON WILL ADVECT N INTO THE FORECAST AREA ON
WED...KEEPING THE E DRY THROUGH THE DAY. WILL KEEP A CHANCE OF
THUNDERSTORMS OVER THE NW HALF OF THE REGION FROM KBIL N AND W...AND
WILL CONTINUE TO MENTION POSSIBLE SEVERE OVER THE N. COLD FRONT
MOVES THROUGH WED NIGHT BRINGING A CHANCE OF THUNDERSTORMS TO MOST
OF THE AREA.
UPPER LOW WILL ROTATE OVER ID THU AND THU NIGHT. CAPES WILL BE VERY
LOW ON THU. HAD LOW POPS ACROSS THE AREA. A SECONDARY COLD FRONT
WITH FRONTOGENESIS WILL MOVE THROUGH THE REGION THU
NIGHT...BRINGING A BETTER CHANCE OF PRECIPITATION.
WILL HAVE A WARM NIGHT TONIGHT AS 850 MB THERMAL RIDGE MOVES INTO
THE AREA AND LOW-LEVEL JET STRENGTHENS OVER THE E. WED WILL BE HOT
WITH 700 MB TEMPERATURES AROUND +14 DEGREES C AHEAD OF THE COLD
FRONT. ARTHUR
.LONG TERM...VALID FOR FRI...SAT...SUN...MON...TUE...
PAC NW UPPER LOW WILL KICK SLOWLY THROUGH THE REGION FRI/SAT...AND
ALL MODELS HAVE TRENDED SIMILARLY WITH REGARD TO STRENGTH AND
TIMING OF THIS FEATURE. WITH CONFIDENCE HAVE RAISED POPS ACROSS
THE REGION ON THESE DAYS. ACTIVITY IN THE WEST SHOULD BE NON-
SEVERE THOUGH WITH LOW WET BULB TEMPS SOME SMALL HAIL IS POSSIBLE
WITH ANY STRONGER CELLS. GFS SHOWS DEEPER MOISTURE AND INSTABILITY
MAY SURGE FROM THE DAKOTAS INTO OUR EAST AHEAD OF THE UPPER
LOW...SO CANNOT RULE OUT THE POTENTIAL FOR SEVERE STORMS IN OUR
EAST ON THESE DAYS...ALONG WITH HEAVY RAIN. SYSTEM WILL EXIT TO
OUR EAST EITHER SATURDAY NIGHT OR EARLY SUNDAY. TEMPS FRIDAY AND
SATURDAY WILL COOL TO SLIGHTLY BELOW NORMAL.
DRIER CONDITIONS SHOULD EMERGE BY SUNDAY IN OUR WEST...WITH A
PERIOD OF DRY WX PERHAPS EXTENDING INTO MONDAY UNDER SHORTWAVE
RIDGING. MODELS DIVERGE A BIT IN THE HANDLING OF THE PACIFIC FLOW
HERE. WILL ADVERTISE A DRY PERIOD SUNDAY INTO MONDAY...THEN SLIGHT
POPS MONDAY AFTERNOON THROUGH TUESDAY AS WE MAY BE IMPACTED BY
PACIFIC SHORTWAVE ENERGY BY THEN. TEMPS SHOULD RETURN BACK TO A
LITTLE ABOVE NORMAL BY DAYS 6/7.
LOOKING FURTHER AHEAD...LATEST GFS/ECMWF SHOW STRONGER RIDGING
WITH NEAR 590DAM HEIGHTS BY WED/THU OF NEXT WEEK. WILL NEED TO
KEEP WATCH OF THIS TREND.
JKL
&&
.AVIATION...
A WEAK DISTURBANCE WILL BRING ISOLATED TO SCATTERED SHOWERS AND
THUNDERSTORMS THIS AFTERNOON AND EVENING...WITH GREATEST COVERAGE
NEAR THE MTNS AND FOOTHILLS...POSSIBLY IMPACTING KLVM AND KSHR AT
TIMES. VFR WILL PREVAIL BUT LOCAL MVFR IS POSSIBLE IN ANY STRONGER
STORMS...AND MOUNTAINS WILL BE OCCASIONALLY OBSCURED. THIS
ACTIVITY WILL DIMINISH AFTER SUNSET. ON WEDNESDAY...AN APPROACHING
COLD FRONT WILL BRING ANOTHER CHANCE OF THUNDERSTORMS ALONG WITH
GUSTIER WINDS. JKL
&&
.PRELIMINARY POINT TEMP/POPS...
WED THU FRI SAT SUN MON TUE
-----------------------------------------------------------
BIL 060/089 052/077 052/072 052/069 051/078 054/082 056/082
22/T 22/T 33/T 34/T 41/B 12/T 22/T
LVM 050/084 043/072 041/069 042/067 046/079 046/082 049/081
33/T 23/T 33/T 34/T 40/B 02/T 22/T
HDN 059/091 053/078 052/074 050/072 050/078 052/082 052/083
21/U 22/T 32/T 34/T 41/B 12/T 22/T
MLS 061/096 058/081 055/076 056/076 055/080 056/083 057/083
21/N 22/T 44/T 34/T 43/T 22/T 22/T
4BQ 061/095 054/081 055/076 054/075 053/079 054/084 055/084
31/N 22/T 44/T 34/T 42/T 12/T 22/T
BHK 057/090 057/080 054/076 055/074 054/076 054/080 057/082
31/N 22/T 36/T 54/T 43/T 22/T 22/T
SHR 054/090 048/078 050/073 048/073 047/076 049/081 050/082
31/U 22/T 32/T 23/T 31/B 12/T 22/T
&&
.BYZ WATCHES/WARNINGS/ADVISORIES...
MT...NONE.
WY...NONE.
&&
$$
WEATHER.GOV/BILLINGS
AREA FORECAST DISCUSSION
NWS HASTINGS NE
1050 PM CDT WED JUN 19 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 00Z TAFS THROUGH 00Z THURSDAY EVENING)
ISSUED AT 647 PM CDT WED JUN 19 2013
VFR CONDITIONS TO CONTINUE THROUGH 10Z...WITH MVFR CONDITIONS
FORECAST 10-14Z...AND THEN VFR CONDITIONS TO FINISH OUT THE TAF
PERIOD.
LOW LEVEL THERMAL ADVECTION ALONG THE AXIS OF A 40-50KT LOW LEVEL
JET COULD PROMOTE INCREASING CLOUD COVER ACROSS THE AREA
TONIGHT...WITH GUIDANCE SUGGESTING A CEILING WILL BE REALIZED
TOWARDS SUNRISE THURSDAY. AN MVFR CEILING...WITH A BASE NEAR
1000FT AGL...IS ALSO FORECAST BY MULTIPLE SETS OF GUIDANCE AND AS
A RESULT...MVFR CONDITIONS HAVE BEEN INTRODUCED TO THE
TAF...10-14Z. THIS CEILING SHOULD SCATTER OUT SHORTLY AFTER
SUNRISE...THUS THE VFR FORECAST 14Z ONWARD. THE AFOREMENTIONED LOW
LEVEL JET MAY ALSO PROMOTE A PERIOD OF LOW LEVEL WIND SHEAR AT
KGRI THURSDAY MORNING...PRIMARILY DURING THE 10-14Z TIME
PERIOD....AND CONFIDENCE IS HIGH ENOUGH TO CONTINUE LOW LEVEL WIND
SHEAR MENTION IN THE TAF. THERE IS A SLIGHT CHANCE FOR SHOWER AND
THUNDERSTORM ACTIVITY AT KGRI TONIGHT...BUT THE PROBABILITY OF
SUCH ACTIVITY BEING REALIZED AT KGRI IS TOO LOW FOR INSERTION INTO
THE TAF AT THIS TIME. VISIBILITY RESTRICTION IS NOT EXPECTED AT
KGRI THROUGH THE NEXT 24 HOURS.
&&
.GID WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
KS...NONE.
&&
$$
UPDATE...HALBLAUB
SHORT TERM...PFANNKUCH
LONG TERM...JCB
AVIATION...BRYANT
AREA FORECAST DISCUSSION
NWS HASTINGS NE
647 PM CDT WED JUN 19 2013
.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 00Z TAFS THROUGH 00Z THURSDAY EVENING)
ISSUED AT 647 PM CDT WED JUN 19 2013
VFR CONDITIONS TO CONTINUE THROUGH 10Z...WITH MVFR CONDITIONS
FORECAST 10-14Z...AND THEN VFR CONDITIONS TO FINISH OUT THE TAF
PERIOD.
LOW LEVEL THERMAL ADVECTION ALONG THE AXIS OF A 40-50KT LOW LEVEL
JET COULD PROMOTE INCREASING CLOUD COVER ACROSS THE AREA
TONIGHT...WITH GUIDANCE SUGGESTING A CEILING WILL BE REALIZED
TOWARDS SUNRISE THURSDAY. AN MVFR CEILING...WITH A BASE NEAR
1000FT AGL...IS ALSO FORECAST BY MULTIPLE SETS OF GUIDANCE AND AS
A RESULT...MVFR CONDITIONS HAVE BEEN INTRODUCED TO THE
TAF...10-14Z. THIS CEILING SHOULD SCATTER OUT SHORTLY AFTER
SUNRISE...THUS THE VFR FORECAST 14Z ONWARD. THE AFOREMENTIONED LOW
LEVEL JET MAY ALSO PROMOTE A PERIOD OF LOW LEVEL WIND SHEAR AT
KGRI THURSDAY MORNING...PRIMARILY DURING THE 10-14Z TIME
PERIOD....AND CONFIDENCE IS HIGH ENOUGH TO CONTINUE LOW LEVEL WIND
SHEAR MENTION IN THE TAF. THERE IS A SLIGHT CHANCE FOR SHOWER AND
THUNDERSTORM ACTIVITY AT KGRI TONIGHT...BUT THE PROBABILITY OF
SUCH ACTIVITY BEING REALIZED AT KGRI IS TOO LOW FOR INSERTION INTO
THE TAF AT THIS TIME. VISIBILITY RESTRICTION IS NOT EXPECTED AT
KGRI THROUGH THE NEXT 24 HOURS.
&&
.GID WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
KS...NONE.
&&
$$
SHORT TERM...PFANNKUCH
LONG TERM...JCB
AVIATION...BRYANT
AREA FORECAST DISCUSSION
NWS HASTINGS NE
1219 AM CDT TUE JUN 18 2013
.UPDATE...
ISSUED AT 1219 AM CDT TUE JUN 18 2013
WV IMAGERY SHOWS A WELL-DEFINED VORT MAX EMBEDDED IN NW FLOW OVER
THE DAKOTAS/MN. A FEW SHWRS/TSTMS ARE STILL ON-GOING WITH THIS
FEATURE. MULTIPLE MODELS DEVELOP SHWRS/TSTMS N OF I-80 BEFORE DAWN
...PRESUMABLY ASSOCIATED WITH THIS VORT MAX AND ASSOCIATED JET
STREAK. SO SOME ADJUSTMENTS HAVE BEEN MADE TO OVERNIGHT POPS/WX.
MEANWHILE...A SMALL MCS CONTINUES OVER THE PANHANDLE AND WHILE
THERE HAS BEEN SOME TEMPO CLEARING OVER S-CNTRL NEB...BLOW-OFF
CLOUD DEBRIS WILL OVERSPREAD THE AREA THRU THE REST OF THE NGT.
TEMPS/DWPTS/WINDS ARE ON TRACK. SO NO SUBSTANTIAL CHANGES NEEDED.
&&
.SHORT TERM...(THIS EVENING THROUGH TUESDAY)
ISSUED AT 440 PM CDT MON JUN 17 2013
THE MAIN CONCERN DURING THE NEXT 24 HOURS CONTINUES TO CENTER
AROUND THE VERY TRICKY...AND CONSTANTLY-EVOLVING THUNDERSTORM
CHANCES...OR LACK THEREOF IN THIS NORTHWEST FLOW PATTERN. ALTHOUGH
AT LEAST A LOW-END RISK FOR SEVERE STORMS CONTINUES THIS
EVENING/TONIGHT MAINLY WEST OF HIGHWAY 281...IT DOES NOT LOOK TO
BE NEARLY AS WIDESPREAD/SIGNIFICANT AS THE SUNDAY EVENING EVENT.
20Z OBJECTIVE SURFACE ANALYSIS INDICATES A FAIRLY NON-DESCRIPT
PATTERN ACROSS THE AREA...WITH THE MAIN SYNOPTIC-SCALE COLD FRONT
NOTED WELL TO THE SOUTH ACROSS OK/NORTHWEST TX. IT HAS BEEN
COMPLETELY RAIN/THUNDER-FREE THE ENTIRE DAY SO FAR CWA-WIDE. WITH
THE MAIN SURFACE FRONT TO THE SOUTH...AND A MODEST 1018 MILLIBAR
RIDGE AXIS CENTERED JUST NORTH OF THE CWA...BREEZES THIS AFTERNOON
ARE GENERALLY SOME VARIATION OF NORTHERLY/EASTERLY AT NO MORE THAN
10 MPH. ALOFT...WATER VAPOR IMAGERY AND SHORT TERM MODEL DATA
DEPICTS THE CONTINUATION OF WEST-NORTHWEST FLOW ALOFT OVER THE
CENTRAL PLAINS...FLOWING OVER THE TOP OF A FAIRLY LOW-AMPLITUDE
RIDGE EXTENDING NORTH-SOUTH THROUGH THE CENTRAL/SOUTHERN ROCKIES.
THERE ARE GENERALLY THREE SHORTWAVE TROUGHS/RIPPLES OF NOTE ACROSS
THE REGION...ONE DEPARTING EASTWARD ALONG THE KS/MO/OK BORDER
AREA...ONE SLIDING SOUTHEAST ACROSS ND...AND THE OTHER A FAIRLY
SUBTLE DISTURBANCE DRIFTING SOUTHEAST ACROSS NORTHWEST NEB...WHICH
HAS HELPED TRIGGER SOME THUS-FAR NON-SEVERE THUNDERSTORMS STILL
50-100 MILES WEST- NORTHWEST OF THE CWA AT THIS HOUR. VISIBLE
SATELLITE IMAGERY REVEALS NOTHING MORE THAN A SCATTERED FAIR
WEATHER CUMULUS FIELD OVER MOST OF THE CWA...WITH A FEW THICKER
MID-CLOUD AREAS DRIFTING INTO NORTHERN/WESTERN COUNTIES OUT AHEAD
OF THE WESTERN NEBRASKA CONVECTION. HIGH TEMPS ARE GENERALLY ON
TRACK TO TOP OUT SOMEWHERE IN THE 80S MOST ALL AREAS.
LATE THIS AFTERNOON INTO TONIGHT...PINNING DOWN THE HOURLY DETAILS
OF POPS/THUNDERSTORMS CONTINUES TO BE A CHALLENGE. REGARDING THE
BIG PICTURE ALOFT BETWEEN NOW AND SUNRISE...THE VERY SUBTLE MID
LEVEL DISTURBANCES ROTATING AROUND THE TOP OF THE RIDGE ACROSS THE
WY/CO/NORTHWEST NEB AREA WILL CONTINUE TO DRIFT SOUTHEAST...WHILE
THE SOMEWHAT MORE ORGANIZED DISTURBANCE NOW OVER ND WILL REACH THE
NORTH CENTRAL IA BY SUNRISE. FOR THE FORECAST...HAVE CONSIDERED A
VARIETY OF DETERMINISTIC AND HIGH-RES MODEL SOLUTIONS
TONIGHT...WHICH INVARIABLY PAINT AT LEAST SLIGHTLY DIFFERENT
PICTURES...BUT LEANING MAINLY TOWARD THE HRRR/4 KM-WRF SOLUTIONS
WHICH SEEM TO HAVE A DECENT HANDLE ON THE ONGOING CONVECTION TO
THE WEST. THROUGH 7PM...HAVE KEPT THE MAJORITY OF THE CWA POP-
FREE...WITH ONLY SLIGHT CHANCES CREEPING INTO ABOUT THE NORTHWEST
1/3 OF THE CWA AS CONVECTION DEVELOPS OVERHEAD AND/OR DRIFTS IN
FROM THE NORTHWEST. BETWEEN 00Z-04Z/7PM-11PM...SPREAD AT LEAST
SLIGHT 20 PERCENT POPS INTO EVEN THE FAR SOUTHEAST
COUNTIES...WHILE RAISING INTO THE 40-50 PERCENT HIGH-CHANCE RANGE
ACROSS MUCH OF THE WEST. BY 00Z...LATEST RAP INDICATES AN
ENVIRONMENT AT LEAST MARGINALLY SUPPORTIVE OF SEVERE
WEATHER...WITH ROUGHLY 1500 J/KG OF 0-1KM CAPE MAINLY IN THE
NORTHWEST 1/2 OF THE CWA...AND 30-40 KNOTS OF 0-6KM DEEP LAYER
SHEAR. AS THE EVENING WEARS ON...INSTABILITY IS PROGGED TO DROP
OFF SLOWLY...BUT LIKELY REMAIN HIGHEST IN KS ZONES. AFTER
MIDNIGHT...CURRENT POPS MAY NOT BE NEARLY HIGH ENOUGH IF IN FACT A
SEMI-ORGANIZED BATCH OF CONVECTION DEVELOPS OVERHEAD OR MOVES
IN...BUT GIVEN INHERENT UNCERTAINTY HAVE CAPPED POPS AT NO MORE
THAN 40-50 PERCENT FOR NOW. GENERALLY HAVE FOLLOWED SPC SREF
SEVERE THUNDER PROBABILITIES BY CONTINUING A MENTION OF STRONG TO
MARGINALLY SEVERE STORMS IN THE HAZARDOUS WEATHER OUTLOOK MAINLY
WEST OF HIGHWAY 281...WITH AN EXPECTATION OF A BROKEN LINE OF
CONVECTION DRIFTING IN. WORST-CASE SCENARIO WOULD SEEM TO BE A
60-70 MPH WIND EVENT IF STORMS CAN ORGANIZE INTO A COLD POOL...BUT
IN THEORY THIS SEEMS FAIRLY UNLIKELY GIVEN THAT CONVECTION SHOULD
LOSE INTENSITY AS IT HEADS EAST OUT OF WESTERN NEB/NORTHWEST
KS...SO WILL ONLY HIGHLIGHT A MARGINALLY SEVERE THREAT AT THIS
TIME. LATER IN THE NIGHT...THERE ARE SUGGESTIONS BY MODELS SUCH AS
THE NAM THAT A MODEST RIBBON OF LOW-MID LEVEL THETA-E ADVECTION IN
THE 850-700MB LAYER COULD SPARK A NEW ROUND OF ELEVATED CONVECTION
MAINLY WITHIN THE NORTHEAST QUADRANT OF THE CWA IN CLOSEST
PROXIMITY TO THE SOUTHEAST-DRIFTING DAKOTAS SHORTWAVE...AND THUS
HAVE PUT POPS BACK INTO THESE NORTHEAST ZONES THROUGH THE NIGHT IN
CASE THIS OCCURS. MADE LITTLE CHANGE TO LOW TEMPS...WITH NEARLY
ALL AREAS SETTLING WITHIN A FEW DEGREES OF 60. ALSO...CANNOT
COMPLETELY RULE OUT SOME LIGHT FOG TONIGHT...BUT NOT EXPECTING
WIDESPREAD VISIBILITY RESTRICTIONS OF 1-2 MILES OR LESS THAT WOULD
REQUIRE FORMAL INCLUSION IN THE FORECAST.
TURNING TO THE TUESDAY DAYTIME PERIOD...UNCERTAINLY JUST KEEPS
GROWING...WITH SOME MODELS CONTINUING TO PAINT DAYTIME MORNING
CONVECTION POSSIBLY AS A CONTINUATION OF THE OVERNIGHT
ACTIVITY...AND ESPECIALLY WITHIN THE NORTHEAST 1/2 OF THE CWA IN
CLOSEST PROXIMITY TO THE SHORTWAVE TROUGH GLANCING BY TO THE EAST.
HOWEVER...BASED ON VARIOUS FACTORS INCLUDING
UNCERTAINTY/CONSISTENCY WITH PREVIOUS FORECAST AND LESS QPF IN
PREVIOUS MODEL RUNS...HAVE OPTED TO GO AHEAD AND LEAVE THE
MAJORITY OF THE DAYTIME HOURS RAIN/THUNDERSTORM-FREE FOR
NOW...WHILE ACKNOWLEDGING THAT THE NEXT FEW SHIFTS MAY HAVE TO
INSERT SOME POST-SUNRISE POPS WITH LIMITED NOTICE. FOR
EXAMPLE...THE PREVIOUS 12Z NAM WAS ESSENTIALLY DRY DURING THE
DAY...BUT THE NEW 18Z RUN NOW HAS PLENTY OF DAYTIME
CONVECTION...WHICH COULD EASILY BE OVERDONE PER THE 12Z 4KM WRF-
NMM...WHICH FITS THE MORE COMMON CONCEPTUAL PICTURE OF LACK
OF FORCING IN THE WAKE OF THE IA SHORTWAVE TROUGH THAT CONTINUES
PASSING SOUTHEAST. THIS CONCEPTUAL PICTURE OF THIS PATTERN WOULD
ALSO SUGGEST THE BEST AFTERNOON STORM CHANCES WOULD BE IN OUR
WESTERN COUNTIES...AND THUS AT LEAST FOR NOW...THE ONLY
OFFICIAL THUNDERSTORM CHANCES IN THE CWA TOMORROW ARE FROM 3-7PM
IN WESTERN COUNTIES...WITH NO STRONG SIGNAL FOR SEVERE STORMS
SHOULD THEY OCCUR. AS HAS BEEN THE CASE LATELY...BE PREPARED FOR
SOME POTENTIALLY NOTABLE CHANGES TO THE TIMING/MAGNITUDE OF THESE
STORM CHANCES...AS LOOKING EVEN BEYOND THE FIRST 12 HOURS IS
PROVING DICEY...AND MORNING CONVECTION COULD BE A WILD CARD.
TEMP-WISE TOMORROW...ASSUMING DAYTIME CONVECTION DOES NOT BLOSSOM
AND CLOUD THINGS UP...EXPECT ANOTHER SEASONABLY WARM DAY AND
NUDGED UP HIGHS SLIGHTLY...GETTING MOST PLACES BETWEEN 81-86
DEGREES. BREEZES WILL START OUT LIGHT BUT PICK UP TO 10-15 MPH
FROM THE SOUTHEAST AS THE AFTERNOON WEARS ON WITH HIGHER GUSTS.
.LONG TERM...(TUESDAY NIGHT THROUGH MONDAY)
ISSUED AT 440 PM CDT MON JUN 17 2013
PRIMARY FORECAST CONCERNS THROUGH THE LONG TERM PERIOD REVOLVE
AROUND PRECIPITATION CHANCES.
THE START OF THE LONG TERM PERIOD TUESDAY EVENING/NIGHT SHOWS THE
REGION REMAINING UNDER THE INFLUENCE OF WEAK/BROAD RIDGING IN THE
UPPER LEVELS...BETWEEN AREAS OF LOW PRESSURE NEAR THE FAR NERN CONUS
AND THE PAC NW COAST. EXPECTING THAT THERE WILL BE ACTIVITY ONGOING
OVER THE HIGH PLAINS BY 00Z...WITH THE MAIN CONCERN BEING HOW FAR
EAST/HOW MUCH OF THE CWA ENDS UP BEING AFFECTED. THIS ACTIVITY
LOOKS TO TAKE ITS TIME SLIDING EAST...WITH LOW POPS IN PLACE THROUGH
THE EARLY/MID EVENING HOURS. MODELS REMAIN IN DECENT AGREEMENT
SHOWING THE WRN PORTIONS OF THE CWA SEEING THE BETTER CHANCES OF
SEEING THUNDERSTORM...BUT ITS POSSIBLE NOT A WHOLE HECK OF A LOT
WILL MAKE IT...SO THERE ISNT A BIG RAMP UP IN POPS DURING THE
OVERNIGHT PERIOD.
AS WE LOOK TOWARD WEDNESDAY AND INTO THURSDAY...PRECIPITATION
CHANCES REMAIN IN THE FORECAST...BUT NOTHING IS CERTAINLY CLEAR
CUT. MODELS ARE IN GOOD AGREEMENT SHOWING THAT ABOVE MENTIONED PAC
NW UPPER LEVEL LOW PRESSURE SYSTEM SLIDING INLAND WEDNESDAY
MORNING...BUT BY THURSDAY MORNING HAS ONLY MOVED INTO THE WA/ID/MT
BORDER AREA. THE MAIN QUESTION LIES WITH THE TIMING/LOCATION OF
PIECES OF ENERGY EJECTED OUT AHEAD OF THE MAIN LOW. ITS IMPACT ON
THE CWA WILL DEPEND ON THE STRENGTH OF THE RIDGE...WHICH AT THIS
POINT LOOK TO REMAIN FAIRLY FLAT/BROAD...NOT STRONG ENOUGH TO SHIFT
THOSE BETTER CHANCES TO THE NORTH. PLENTY OF UNCERTAINTY ALREADY ON
WEDNESDAY...SOME MODELS SHOW THE WEST WITH THE BETTER CHANCES/OTHERS
THE EAST...AND DECIDED AT THIS POINT TO KEEP POPS ON THE LOWER
SIDE. WEDNESDAY NIGHT...DIDNT MAKE SIGNIFICANT CHANGES TO THE POPS
/WHICH REMAIN IN THE CHANCE CATEGORY/...WITH THERE STILL BEING SOME
SUPPORT OF ANOTHER ROUND OF ACTIVITY FROM THE WEST SLIDING
THROUGH...BUT WITH OTHERS STARTING TO TREND AWAY FROM THAT WASNT
GOING TO INCREASE THOSE CHANCES.
BY 12Z THURSDAY...MODELS STARTING TO DEPICT SOME SLIGHT
AMPLIFICATION OF THE RIDGE OVER THE PLAINS AS THAT PAC NW LOW
REMAINS IN PLACE. MAIN QUESTION IS WITH PRECIP CHANCES...AND
WHAT/IF ANYTHING IS LINGERING IN THE EAST IN THE MORNING AND WILL
ANYTHING FIRE IN THE WEST DURING THE AFTERNOON. ACCOMPANYING THIS
BUMP UP IN THE RIDGE IS WARMING TEMPERATURES IN THE LOWER/MID
LEVELS...AND CAPPING STARTS TO BECOME MORE OF A CONCERN. SOME
MODELS HAVE STARTED TRENDING TOWARD THAT CAP BUILDING IN AND KEEPING
THE DAY DRY...BUT A FEW ARE HANGING ON TO THE POTENTIAL FOR SOME
LINGERING ACTIVITY...SO WHILE POPS WERE LOWERED...THEY WERE NOT
COMPLETELY REMOVED AT THIS POINT.
THE FORECAST FOR FRIDAY AND SATURDAY IS DRY. THOUGH THE UPPER LEVEL
PATTERN IS BECOMING MORE SOUTHWESTERLY AS THE MAIN RIDGE AXIS
BECOMES MORE ORIENTATED IN A SW/NE DIRECTION JUST EAST OF THE
CWA...THE WARMER MID LEVEL TEMPS/CAPPING AND LOCATION OF SFC
BOUNDARIES LOOKS TO KEEP THE BETTER CHANCES JUST OFF TO THE CWA.
FOR SUNDAY AND MONDAY...PRECIP CHANCES LOOK TO MAKE A RETURN TO THE
CWA. THE LOW OVER THE PAC NW FINALLY STARTS TO SHIFT TO THE E/NE
INTO CENTRAL CANADA...BREAKING DOWN/SHIFTING THE RIDGE ONCE IN PLACE
OVER THE CENTRAL PLAINS...AND AGAIN ALLOWING FOR THE OPPORTUNITY FOR
DISTURBANCES IN THE MAIN FLOW TO BRING CHANCES FOR THUNDERSTORMS.
AS FAR AS TEMPERATURES GO...EXPECTING TO SEE A GRADUAL WARMING
TREND...MAINLY INTO THE FRI/SAT TIME FRAME WITH THAT
AMPLIFICATION OF THE RIDGE...BEFORE MODERATING BACK DOWN A TOUCH
INTO SUN/MON. CURRENTLY HAVE HIGHS RISING TO THE 90S FOR BOTH FRI
AND SAT /ADDITION UPWARD ADJUSTMENTS MAY BE NEEDED/...WITH MID 80S
TO MID 90S FOR SUN/MON.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT)
ISSUED AT 1219 AM CDT TUE JUN 18 2013
REST OF TNGT: VFR WITH MOSTLY BKN CIRRUS. HOWEVER...WE DO NEED TO
WATCH POTENTIAL FOR A TEMPO MVFR OR IFR VSBY IN DEVELOPING SHWRS/
TSTMS. WINDS WILL BE LIGHT AND MOSTLY FROM THE NE.
TUE: VFR BUT THERE IS POTENTIAL FOR TEMPO MVFR OR IFR VSBY IN SCT
SHWRS/TSTMS UNTIL 15Z. SE WINDS WILL AVERAGE AROUND 10 KTS.
TUE THRU 06Z: VFR. SE WINDS LESS THAN 10 KTS.
CIG CONFIDENCE: AVERAGE
VSBY CONFIDENCE: AVERAGE
WIND CONFIDENCE: AVERAGE
WX CONFIDENCE: AVERAGE
&&
.GID WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
KS...NONE.
&&
$$
UPDATE...HALBLAUB
SHORT TERM...PFANNKUCH
LONG TERM...ADO
AVIATION...HALBLAUB
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
1113 PM EDT WED JUN 19 2013
.SYNOPSIS...
AS THE COLD FRONT SAGS FARTHER SOUTH THROUGH THIS EVENING...THE
RISK OF RAIN WILL SLOWLY END FROM NORTH TO SOUTH. THIS FRONT WILL
LINGER SOUTH OF COASTAL NORTH CAROLINA AS HIGH PRESSURE NOSES IN
FROM THE NORTH...PUSHING SOME DRIER AIR ACROSS THE REGION LATE
TONIGHT THROUGH THURSDAY. THE LINGERING FRONT WILL NUDGE BACK TO
THE NORTH FRIDAY INTO THIS WEEKEND...ACCOMPANIED BY INCREASING
CLOUDS AND CHANCE FOR CONVECTION MAINLY ACROSS THE COASTAL
CAROLINAS.
&&
.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 300 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 300 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 /03Z THURSDAY THROUGH MONDAY/...
AS OF 00Z...A COLD FRONT REMAINS JUST SOUTH OF OUR CWA THIS
EVENING...WITH SHOWERS/T-STORMS DEVELOPING ALONG THE FRONT MOVING
OFFSHORE. WILL KEEP VCSH FOR KMYR/KCRE THRU THE EVENING HOURS...
ALTHOUGH THE DRIER AIR BEHIND THE FRONT LIKELY WILL LIMIT ANY PCPN
IN THE FCST AREA. GUIDANCE AND FCST SOUNDINGS SUPPORT MVFR/IFR CIGS
DEVELOPING AT ALL TERMS AFTER 06Z...SLIGHTLY FAVORING THE INLAND
SITES. BEST CHANCES FOR IFR APPEAR TO BE FROM 09-12Z ATTM. MVFR CIGS
COULD LINGER THRU THE MORNING HOURS...ESPECIALLY ALONG THE COAST...
BEFORE DRYING OUT IN THE AFTN AS HIGH PRESSURE INCHES DOWN FROM THE
NORTH. E/NE WINDS WILL STRENGTHEN TO 10-15 KTS DURING THE DAY AS THE
SFC PRESSURE GRADIENT TIGHTENS OVER THE CAROLINAS.
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 1045 PM WEDNESDAY...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 300 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 300 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.
&&
$$
SYNOPSIS...RGZ
NEAR TERM...DCH
SHORT TERM...RGZ
LONG TERM...JDW
AVIATION...BJR
AREA FORECAST DISCUSSION...UPDATED
NWS WILMINGTON NC
745 PM EDT WED JUN 19 2013
.SYNOPSIS...
AS THE COLD FRONT SAGS FARTHER SOUTH THROUGH THIS EVENING...THE
RISK OF RAIN WILL SLOWLY END FROM NORTH TO SOUTH. THIS FRONT WILL
LINGER SOUTH OF COASTAL NORTH CAROLINA AS HIGH PRESSURE NOSES IN
FROM THE NORTH...PUSHING SOME DRIER AIR ACROSS THE REGION LATE
TONIGHT THROUGH THURSDAY. THE LINGERING FRONT WILL NUDGE BACK TO
THE NORTH FRIDAY INTO THIS WEEKEND...ACCOMPANIED BY INCREASING
CLOUDS AND CHANCE FOR CONVECTION MAINLY ACROSS THE COASTAL
CAROLINAS.
&&
.NEAR TERM /THROUGH THURSDAY/...
AS OF 645 PM WEDNESDAY...CURRENT PCPN AND LATEST HRRR INDICATE
POPS WILL CONTINUE THIS EVENING FOR MAINLY THE SOUTHERN PORTIONS
OF THE ILM CWA...AND THE IMMEDIATE COAST UP TO BALD HEAD
ISLAND. AND ALSO EXTENDING ACROSS THE ADJACENT COASTAL AND
OFFSHORE ATLANTIC WATERS. OUT OF ALL THE PROGS...THE LATEST HRRR
CONTINUES TO ILLUSTRATE THE CURRENT AND PROGGED LOCATION OF THIS
FRONT...ESPECIALLY LOOKING AT THE SFC WIND FIELD IN ITS WAKE. PCPN
ACROSS THE MENTIONED AREAS EARLY THIS EVENING HAS MAINLY BEEN
BLOW-OFF STRATIFORM RAINS FROM THE CONVECTION AFFECTING THE CHS
CWA. ONCE DAY-TIME HEATING ENDS...THE CONVECTION SHOULD DECREASE
IN COVERAGE BUT LIKELY LINGER DURING THE OVERNITE...AND WILL
THEREFORE KEEP A LOW POP ACROSS THE SOUTHERN PORTIONS OF THE FA.
LOOKING AT THE LATEST SAT IMAGERY...DO NOT SEE THE CLEARING BEHIND
THE FRONT THAT MODELS TRY TO INFILTRATE ACROSS THE FA OVERNITE.
WILL THEREFORE...INCREASE CLOUDINESS ACROSS THE FA OVERNIGHT. AS A
RESULT OF A LOW BLANKET OF CLOUDS...WILL INCREASE MIN TEMPS BY A
DEGREE...UP TO 3. IN ADDITION...HAVE ALSO UPPED HOURLY SFC
DEWPOINTS DUE TO THE CANOPY OF CLOUDS AND LACK OF DRIER AIR
MAKING IT THIS FAR SOUTH.
PREVIOUS DISCUSSION....................................
AS OF 300 PM WEDNESDAY...THE SURFACE COLD FRONT HAS PUSHED MUCH
FARTHER SOUTH THAN I HAD INITIALLY EXPECTED AND HAS NOW CROSSED
THE SANTEE RIVER INTO NORTHERN CHARLESTON COUNTY SC. THIS HAS
TAKEN VIRTUALLY ALL THE SURFACE BASED INSTABILITY SOUTH OF THE
SANTEE RIVER WITH THE HEAVIER THUNDERSTORM ACTIVITY CONFINED DOWN
THERE. LIGHTER STRATIFORM RAIN BLOWING NORTHEAST FROM THE STORMS
IS SPREADING ACROSS PARTS OF WILLIAMSBURG AND GEORGETOWN COUNTIES
AND MAY PUSH UP THE COAST TO MYRTLE BEACH AND EVEN BALD HEAD
ISLAND BY EARLY EVENING. RAINFALL AMOUNTS WITHIN THIS RAIN SHOULD
AVERAGE ONLY A COUPLE HUNDREDTHS OF AN INCH...MUCH LIGHTER THAN
BEING EXPERIENCED SOUTH OF GEORGETOWN.
MODELS ARE STRUGGLING TO FIND THE ACTUAL POSITION OF THE SURFACE
COLD FRONT. OF THE 10 MODELS I LOOK AT...ONLY THREE OF THEM SHOW
THE CORRECT FRONTAL POSITION: THE HRRR...ECMWF AND CANADIAN. THE
THREE OF THESE MODELS SHOW THE FRONT REMAINING SOUTH OF GEORGETOWN
THROUGH THE NIGHT...ALTHOUGH THEY ALSO SHOW THE REDEVELOPMENT OF
THUNDERSTORMS ALONG AND JUST NORTH OF THE SURFACE FRONTAL POSITION
AROUND MIDNIGHT. NOCTURNAL REDEVELOPMENT OF CONVECTION IS CERTAINLY
SOMETHING WE SEE DURING THE SUMMER PARTICULARLY IN A VERY MOIST
AIRMASS LIKE WE HAVE HERE...SO AFTER RAM PING POPS DOWN THIS EVENING
I WILL SHOW A TREND TOWARD HIGHER POPS...30-40 PERCENT IN THE
GEORGETOWN VICINITY OVERNIGHT.
LOWS TONIGHT SHOULD RANGE FROM 65-70...WARMEST ALONG THE SC COAST
AND COOLER IN THE ELIZABETHTOWN/LUMBERTON AREA.
&&
.SHORT TERM /THURSDAY NIGHT THROUGH FRIDAY NIGHT/...
AS OF 300 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 300 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 /00Z THURSDAY THROUGH MONDAY/...
AS OF 00Z...A COLD FRONT REMAINS JUST SOUTH OF OUR CWA THIS
EVENING...WITH SHOWERS/T-STORMS DEVELOPING ALONG THE FRONT MOVING
OFFSHORE. WILL KEEP VCSH FOR KMYR/KCRE THRU THE EVENING HOURS...
ALTHOUGH THE DRIER AIR BEHIND THE FRONT LIKELY WILL LIMIT ANY PCPN
IN THE FCST AREA. GUIDANCE AND FCST SOUNDINGS SUPPORT MVFR/IFR CIGS
DEVELOPING AT ALL TERMS AFTER 06Z...SLIGHTLY FAVORING THE INLAND
SITES. BEST CHANCES FOR IFR APPEAR TO BE FROM 09-12Z ATTM. MVFR CIGS
COULD LINGER THRU THE MORNING HOURS...ESPECIALLY ALONG THE COAST...
BEFORE DRYING OUT IN THE AFTN AS HIGH PRESSURE INCHES DOWN FROM THE
NORTH. E/NE WINDS WILL STRENGTHEN TO 10-15 KTS DURING THE DAY AS THE
SFC PRESSURE GRADIENT TIGHTENS OVER THE CAROLINAS.
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 700 PM WEDNESDAY...AS MENTIONED BY THE PRIOR
FORECASTER...ONLY A FEW MODELS ARE HANDLING THE CURRENT LOCATION
OF THE COLD FRONT THAT BASICALLY WILL STALL AND REMAIN SOUTH AND
WELL EAST AND OFFSHORE FROM THE ILM COASTAL WATERS. 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...EXCEPT 25 KT ACROSS THE OUTER WATERS OFF CAPE FEAR.
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.
PREVIOUS DISCUSSION....................................
AS OF 300 WEDNESDAY...DEFYING ALL EXPECTATIONS...THE FRONT HAS
CONTINUED TO PUSH FARTHER SOUTH AND IS NOW IN NORTHERN CHARLESTON
COUNTY ABOUT 5-10 MILES SOUTH OF THE SANTEE RIVER. OF 10 MODELS I
HAVE ACCESS TO...ONLY THREE HAVE ANY CLUE ABOUT THE CURRENT POSITION
OF THIS FRONT: THE HRRR...ECMWF AND CANADIAN. BLENDING THE OUTPUT OF
THESE THREE MODELS TOGETHER SHOWS THE FRONT SHOULD REMAIN SOUTH OF
OUR AREA OVERNIGHT WITH HIGH PRESSURE OVER THE EASTERN GREAT LAKES
BUILDING SOUTHWARD INTO THE MID-ATLANTIC REGION. THIS WILL TIGHTEN
THE PRESSURE GRADIENT LOCALLY PRODUCING A MODERATE NORTHEAST SURGE
OVERNIGHT. AT THIS TIME IT APPEARS WINDS AND SEAS WILL REMAIN JUST
BELOW THE CRITERIA NEEDED TO ADD AN "EXERCISE CAUTION" HEADLINE TO
THE FORECAST. THE ROUGHEST CONDITIONS ARE EXPECTED NORTH OF CAPE
FEAR. IN TERMS OF SHOWER AND THUNDERSTORM POTENTIAL...THE FRONT HAS
TAKEN MOST OF THE ATMOSPHERIC INSTABILITY SOUTH OF OUR REGION.
SHOWERS COULD REDEVELOP JUST NORTH OF THE FRONT MAINLY FROM MYRTLE
BEACH SOUTH TONIGHT.
SHORT TERM /THURSDAY THROUGH FRIDAY NIGHT/...
AS OF 300 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 300 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.
&&
$$
SYNOPSIS...RGZ
NEAR TERM...DCH/TRA
SHORT TERM...RGZ
LONG TERM...JDW
AVIATION...BJR
MARINE...
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
741 PM EDT WED JUN 19 2013
.SYNOPSIS...
AS COLD FRONT SAGS FARTHER SOUTH THROUGH THIS EVENING...THE RISK
OF RAIN WILL SLOWLY END FROM NORTH TO SOUTH. THIS FRONT WILL
LINGER NEAR OR JUST SOUTH OF COASTAL NORTH CAROLINA AS HIGH
PRESSURE NOSES IN FROM THE NORTH PUSHING SOME DRIER AIR IN THROUGH
THURSDAY. THE LINGERING FRONT WILL NUDGE BACK TO THE NORTH FRIDAY
INTO THIS WEEKEND INCREASING CLOUDS AND CHANCE OF SHOWERS MAINLY
ACROSS THE COASTAL CAROLINAS.
&&
.NEAR TERM /THROUGH THURSDAY/...
AS OF 645 PM WEDNESDAY...CURRENT PCPN AND LATEST HRRR INDICATE
POPS WILL CONTINUE THIS EVENING FOR MAINLY THE SOUTHERN PORTIONS
OF THE ILM CWA...AND THE IMMEDIATE COAST UP TO BALD HEAD
ISLAND. AND ALSO EXTENDING ACROSS THE ADJACENT COASTAL AND
OFFSHORE ATLANTIC WATERS. OUT OF ALL THE PROGS...THE LATEST HRRR
CONTINUES TO ILLUSTRATE THE CURRENT AND PROGGED LOCATION OF THIS
FRONT...ESPECIALLY LOOKING AT THE SFC WIND FIELD IN ITS WAKE. PCPN
ACROSS THE MENTIONED AREAS EARLY THIS EVENING HAS MAINLY BEEN
BLOW-OFF STRATIFORM RAINS FROM THE CONVECTION AFFECTING THE CHS
CWA. ONCE DAY-TIME HEATING ENDS...THE CONVECTION SHOULD DECREASE
IN COVERAGE BUT LIKELY LINGER DURING THE OVERNITE...AND WILL
THEREFORE KEEP A LOW POP ACROSS THE SOUTHERN PORTIONS OF THE FA.
LOOKING AT THE LATEST SAT IMAGERY...DO NOT SEE THE CLEARING BEHIND
THE FRONT THAT MODELS TRY TO INFILTRATE ACROSS THE FA OVERNITE.
WILL THEREFORE...INCREASE CLOUDINESS ACROSS THE FA OVERNIGHT. AS A
RESULT OF A LOW BLANKET OF CLOUDS...WILL INCREASE MIN TEMPS BY A
DEGREE...UP TO 3. IN ADDITION...HAVE ALSO UPPED HOURLY SFC
DEWPOINTS DUE TO THE CANOPY OF CLOUDS AND LACK OF DRIER AIR
MAKING IT THIS FAR SOUTH.
PREVIOUS DISCUSSION...............................................
AS OF 300 PM WEDNESDAY...THE SURFACE COLD FRONT HAS PUSHED MUCH
FARTHER SOUTH THAN I HAD INITIALLY EXPECTED AND HAS NOW CROSSED
THE SANTEE RIVER INTO NORTHERN CHARLESTON COUNTY SC. THIS HAS
TAKEN VIRTUALLY ALL THE SURFACE BASED INSTABILITY SOUTH OF THE
SANTEE RIVER WITH THE HEAVIER THUNDERSTORM ACTIVITY CONFINED DOWN
THERE. LIGHTER STRATIFORM RAIN BLOWING NORTHEAST FROM THE STORMS
IS SPREADING ACROSS PARTS OF WILLIAMSBURG AND GEORGETOWN COUNTIES
AND MAY PUSH UP THE COAST TO MYRTLE BEACH AND EVEN BALD HEAD
ISLAND BY EARLY EVENING. RAINFALL AMOUNTS WITHIN THIS RAIN SHOULD
AVERAGE ONLY A COUPLE HUNDREDTHS OF AN INCH...MUCH LIGHTER THAN
BEING EXPERIENCED SOUTH OF GEORGETOWN.
MODELS ARE STRUGGLING TO FIND THE ACTUAL POSITION OF THE SURFACE
COLD FRONT. OF THE 10 MODELS I LOOK AT...ONLY THREE OF THEM SHOW
THE CORRECT FRONTAL POSITION: THE HRRR...ECMWF AND CANADIAN. THE
THREE OF THESE MODELS SHOW THE FRONT REMAINING SOUTH OF GEORGETOWN
THROUGH THE NIGHT...ALTHOUGH THEY ALSO SHOW THE REDEVELOPMENT OF
THUNDERSTORMS ALONG AND JUST NORTH OF THE SURFACE FRONTAL POSITION
AROUND MIDNIGHT. NOCTURNAL REDEVELOPMENT OF CONVECTION IS CERTAINLY
SOMETHING WE SEE DURING THE SUMMER PARTICULARLY IN A VERY MOIST
AIRMASS LIKE WE HAVE HERE...SO AFTER RAM PING POPS DOWN THIS EVENING
I WILL SHOW A TREND TOWARD HIGHER POPS...30-40 PERCENT IN THE
GEORGETOWN VICINITY OVERNIGHT.
LOWS TONIGHT SHOULD RANGE FROM 65-70...WARMEST ALONG THE SC COAST
AND COOLER IN THE ELIZABETHTOWN/LUMBERTON AREA.
&&
.SHORT TERM /THURSDAY NIGHT THROUGH FRIDAY NIGHT/...
AS OF 300 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 300 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 /00Z THURSDAY THROUGH MONDAY/...
AS OF 00Z...A COLD FRONT REMAINS JUST SOUTH OF OUR CWA THIS
EVENING...WITH SHOWERS/T-STORMS DEVELOPING ALONG THE FRONT MOVING
OFFSHORE. WILL KEEP VCSH FOR KMYR/KCRE THRU THE EVENING HOURS...
ALTHOUGH THE DRIER AIR BEHIND THE FRONT LIKELY WILL LIMIT ANY PCPN
IN THE FCST AREA. GUIDANCE AND FCST SOUNDINGS SUPPORT MVFR/IFR CIGS
DEVELOPING AT ALL TERMS AFTER 06Z...SLIGHTLY FAVORING THE INLAND
SITES. BEST CHANCES FOR IFR APPEAR TO BE FROM 09-12Z ATTM. MVFR CIGS
COULD LINGER THRU THE MORNING HOURS...ESPECIALLY ALONG THE COAST...
BEFORE DRYING OUT IN THE AFTN AS HIGH PRESSURE INCHES DOWN FROM THE
NORTH. E/NE WINDS WILL STRENGTHEN TO 10-15 KTS DURING THE DAY AS THE
SFC PRESSURE GRADIENT TIGHTENS OVER THE CAROLINAS.
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 700 PM WEDNESDAY...AS MENTIONED BY THE PRIOR
FORECASTER...ONLY A FEW MODELS ARE HANDLING THE CURRENT LOCATION
OF THE COLD FRONT THAT BASICALLY WILL STALL AND REMAIN SOUTH AND
WELL EAST AND OFFSHORE FROM THE ILM COASTAL WATERS. 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...EXCEPT 25 KT ACROSS THE OUTER WATERS OFF CAPE FEAR.
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.
PREVIOUS DISCUSSION................................................
AS OF 300 WEDNESDAY...DEFYING ALL EXPECTATIONS...THE FRONT HAS
CONTINUED TO PUSH FARTHER SOUTH AND IS NOW IN NORTHERN CHARLESTON
COUNTY ABOUT 5-10 MILES SOUTH OF THE SANTEE RIVER. OF 10 MODELS I
HAVE ACCESS TO...ONLY THREE HAVE ANY CLUE ABOUT THE CURRENT POSITION
OF THIS FRONT: THE HRRR...ECMWF AND CANADIAN. BLENDING THE OUTPUT OF
THESE THREE MODELS TOGETHER SHOWS THE FRONT SHOULD REMAIN SOUTH OF
OUR AREA OVERNIGHT WITH HIGH PRESSURE OVER THE EASTERN GREAT LAKES
BUILDING SOUTHWARD INTO THE MID-ATLANTIC REGION. THIS WILL TIGHTEN
THE PRESSURE GRADIENT LOCALLY PRODUCING A MODERATE NORTHEAST SURGE
OVERNIGHT. AT THIS TIME IT APPEARS WINDS AND SEAS WILL REMAIN JUST
BELOW THE CRITERIA NEEDED TO ADD AN "EXERCISE CAUTION" HEADLINE TO
THE FORECAST. THE ROUGHEST CONDITIONS ARE EXPECTED NORTH OF CAPE
FEAR. IN TERMS OF SHOWER AND THUNDERSTORM POTENTIAL...THE FRONT HAS
TAKEN MOST OF THE ATMOSPHERIC INSTABILITY SOUTH OF OUR REGION.
SHOWERS COULD REDEVELOP JUST NORTH OF THE FRONT MAINLY FROM MYRTLE
BEACH SOUTH TONIGHT.
SHORT TERM /THURSDAY THROUGH FRIDAY NIGHT/...
AS OF 300 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 300 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.
&&
$$
SYNOPSIS...RGZ
NEAR TERM...DCH/TRA
SHORT TERM...RGZ
LONG TERM...JDW
AVIATION...BJR
AREA FORECAST DISCUSSION
NWS RALEIGH NC
250 PM EDT TUE JUN 18 2013
.SYNOPSIS...
A COLD FRONT WILL APPROACH FROM THE NORTHWEST LATE TODAY...AND CROSS
THE REGION TONIGHT. HIGH PRESSURE WILL BUILD INTO CENTRAL NC FROM
THE NORTH WEDNESDAY THROUGH THURSDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 250 PM TUESDAY...
SLIGHT TO MODERATELY UNSTABLE AIR MASS RESIDES OVER CENTRAL NC AT
MID-AFTERNOON THANKS TO PEAKS OF SUN HEATING UP AN AIR MASS WITH SFC
DEWPOINTS IN THE UPPER 60S TO LOWER 70S. UPSTAIRS...A VORT MAXIMUM
OVER THE CENTRAL APPALACHIANS CONTINUES TO ROTATE EASTWARD WITH
ATTENDANT SHEAR AXIS EXTENDING SWWD ALONG THE SPINE OF THE SOUTHERN
APPALACHIANS. THIS MID LEVEL FEATURE AIDING TO ENHANCE THE 925-850MB
FLOW WHICH IS ADVECTING ADDITIONAL MOISTURE INTO THE COLUMN. LATEST
SATELLITE TOTAL BLEND PRECIP WATER PRODUCT DEPICTS VALUES BETWEEN
1.8-2 INCHES OVER OUR FORECAST AREA. THOUGH MID LEVEL LAPSE RATES
ARE MEAGER...ENOUGH JUICE EXISTS IN THE ATMOSPHERE TO SUPPORT THE
DEVELOPMENT OF NUMEROUS SHOWERS AND SCATTERED THUNDERSTORMS LATE
THIS AFTERNOON THROUGH EARLY EVENING AS THE MID LEVEL SHEAR AXIS
CROSSES THE REGION. CURRENT 0-6KM SHEAR VALUES IN THE 30-40KT RANGE
OVER THE NW PIEDMONT SUPPORT THE IDEA OF CONVECTION FORMING INTO A
LINE AS IT MARCHES EAST-SE. CANNOT RULE OUT THE POSSIBILITY OF AN
ISOLATED STRONG-SEVERE STORM WITH WIND GUSTS 40-50 MPH. STILL
BELIEVE MAIN WEATHER HAZARD WILL BE TORRENTIAL DOWNPOURS WITH
RAINFALL RATES 2-3 INCHES PER HOUR POSSIBLE IN A FEW OF THE STORMS.
FORTUNATELY STEERING WINDS CLOSE TO 25KTS SO STORMS WITH THIS
MAGNITUDE OF RAIN SHOULD NOT SETTLE OVER ONE SPOT VERY LONG. BULK OF
CONVECTIVE ALLOWING MODELS AS WELL AS THE 11Z HRRR SUGGEST THE
BROKEN LINE OF CONVECTION CROSSING THE PIEDMONT BETWEEN
21Z-00Z...AND INTO THE SANDHILLS AND COASTAL PLAIN 23Z-02Z.
PLAN TO MAINTAIN CATEGORICAL POPS IN THE NW PIEDMONT LATE THIS
AFTERNOON THEN SPREAD THESE HIGHER POPS SEWD WITH TIME. WILL
INTRODUCE DECREASING POPS BY EARLY EVENING IN THE NW PIEDMONT...THEN
TREND POPS LOWER OVER THE REMAINDER OF THE FORECAST BETWEEN 02Z-06Z.
OVERNIGHT...SFC COLD FRONT WILL PROGRESS SEWD AND SHOULD LIE WSW-ENE
ACROSS OUR FAR SOUTHERN-SE COUNTIES AT DAYBREAK. THIS FEATURE
SHOULD INTERACT WITH AVAILABLE MOISTURE TO TRIGGER SCATTERED SHOWERS
OVERNIGHT. STILL MUGGY OVERNIGHT THOUGH THE FAR N-NW SECTIONS MAY
START TO FEEL A LITTLE LESS HUMID BY DAYBREAK. MIN TEMPS MID 60S TO
NEAR 70.
&&
.SHORT TERM /WEDNESDAY AND WEDNESDAY NIGHT/...
AS OF 250 PM TUESDAY...
STRONGER S/W IN THE NORTHERN STREAM WILL CROSS THE NORTHERN
MID ATLANTIC WHILE THE TAIL END OF THE SHEAR AXIS APPROACHES OUR
NORTHERN COUNTIES BY EARLY EVENING. NLY FLOW BEHIND THE INITIAL MID
LEVEL TROUGH WILL ADVECT DRIER AND SLIGHTLY MORE STABLE AIR INTO
CENTRAL NC. WHILE CLOUDS WILL LIKELY STICK AROUND DUE TO RESIDUAL
MOISTURE AND CYCLONIC CURVATURE IN THE MID LEVEL FLOW...CONVECTIVE
COVERAGE SHOULD BE LESS NUMEROUS WEDNESDAY AFTERNOON AND NOT AS
ROBUST. EXPECT TWO MAIN AREAS OF PRECIP...ONE OVER THE FAR SOUTH IN
VICINITY OF THE NEARLY STATIONARY SFC FRONT...AND THE OTHER OVER THE
FAR NORTH AHEAD OF THE SWD ADVANCING MID LEVEL SHEAR AXIS. PLAN TO
CAP POPS NO HIGHER THAN 50 PERCENT (NEAR SC BORDER) WITH A 1-IN-3
CHANCE ACROSS THE NORTH. AS ATMOSPHERE STABILIZES IN THE EARLY
EVENING...EXPECT MAJORITY OF THE CONVECTION TO DISSIPATE THOUGH A
STRAY SHOWER MAY STILL OCCUR IN VICINITY OF THE SHEAR AXIS ACROSS
THE NORTH. THIS SHEAR AXIS WILL CONTINUE TO PROGRESS SE OVERNIGHT
AND EXIT THE REGION BY DAYBREAK THU. SUBSIDENCE BEHIND THIS FEATURE
WILL AID TO DISSIPATE THE CLOUD COVERAGE AFTER MIDNIGHT.
EXPECT A FAIRLY UNIFORM TEMP FIELD WEDNESDAY DUE TO CLOUD COVERAGE
AND LOW LEVEL COLD AIR ADVECTION. MAX TEMPS NEAR 80 NORTH TO LOWER
80S SOUTH. MIN TEMPS WEDNESDAY NIGHT IN THE MID 60S.
&&
.LONG TERM /THURSDAY THROUGH TUESDAY/...
AS OF 215 PM TUESDAY...
THURSDAY THROUGH FRIDAY...HEIGHTS ALOFT RISE OVER CENTRAL NORTH
CAROLINA...WITH A SUBSIDENT AIR MASS IN PLACE OVER THE AREA.
PRECIPITABLE WATER VALUES REMAIN HIGHER THURSDAY RELATIVE TO
FRIDAY...BETWEEN AN INCH AND 1.5 INCHES ON THE FORMER COMPARED TO A
DECREASE FROM THE NORTHEAST TO AT OR BELOW AN INCH FRIDAY. BOTH THE
GFS AND NAM BUFR SOUNDINGS...AND PARTICULARLY THE LATTER...FORECAST
ENOUGH MOISTURE AROUND 850MB THURSDAY FOR AREAS OF CU TO FORM...MORE
LIKELY TOWARD THE WESTERN PIEDMONT WHERE THE 850MB MOISTURE IS
HIGHEST. K INDICES FALL FROM THE NORTHEAST AS WELL THURSDAY
AFTERNOON CONTINUING INTO FRIDAY...WITH K INDICES WELL INTO NEGATIVE
VALUES BY FRIDAY AFTERNOON. IN TERMS OF DEEP CONVECTION...AMPLE
OVERALL CIN AND GRADUAL WARMING ALOFT WITH CONVERGENCE ALOFT SHOULD
PRECLUDE THAT. THERE SHOULD BE A FEW MORNING GUSTS WITH INITIAL
MIXING THURSDAY IN THE LOWER TO MID TEENS KTS IN THE MODESTLY TIGHT
GRADIENT BETWEEN AN INVERTED TROUGH OFF OF THE COAST AND SURFACE
HIGH PRESSURE BUILDING IN FROM THE NORTHWEST...BUT OVERALL 925MB
WINDS ARE MAINLY AROUND 10KT. 1000-850MB THICKNESSES SUGGEST HIGHS
IN THE LOWER TO MID 80S BOTH DAYS...CLOSE TO OR ON THE LOWER SIDE OF
MOS GUIDANCE. OVERNIGHT LOWS THURSDAY NIGHT AROUND 60 TO THE MID
60S...MINS POSSIBLY TEMPERED A LITTLE OVER THE SOUTHWEST PIEDMONT BY
SLIGHTLY GREATER UPPER-LEVEL MOISTURE FORECAST BY BOTH THE NAM AND
THE GFS.
FRIDAY NIGHT THROUGH TUESDAY...UPPER RIDGING CONTINUES TO BUILD IN.
AROUND THE RIDGE...THERE COULD BE A WEAK MID-LEVEL SHORTWAVE OR TWO
THAT ATTEMPTS TO MOVE...OR HAS SOME SUCCESS MOVING...INTO CENTRAL
NORTH CAROLINA ESPECIALLY LATE IN THE WEEKEND AND EARLY NEXT WEEK.
THE MOISTURE OF THE MEAN AIR MASS...AND MOISTURE AT THE
SURFACE...INCREASE SUNDAY INTO MONDAY...WITH SURFACE DEW POINTS
EXPECTED TO INCREASE TO AROUND 70F BY MONDAY...CONTINUING INTO
TUESDAY. WITH SURFACE RIDGING OVER THE GULF CURRENTLY FORECAST...IT
SHOULD BE A GRADUAL MOISTURE INCREASE ESPECIALLY AT THE
SURFACE...AND COARSE MODEL SOUNDINGS AT LEAST INTO SUNDAY AFTERNOON
HAVE A GOOD CONSENSUS OF AT LEAST BEING WEAKLY CAPPED ALOFT. WILL
MAINTAIN THE DRY FORECAST FRIDAY NIGHT THROUGH THE WEEKEND...BUT
WITH INCREASING MOISTURE...SOME GUIDANCE SUGGESTING A WEAKNESS IN
THE MID-LEVEL HEIGHTS TRANSLATING INTO COOLING ALOFT...AT LEAST SOME
QPF BY MUCH OF THE CURRENT LONG-TERM GUIDANCE...AND MEX MOS POPS
NEAR OR ABOVE CLIMATOLOGY...WILL INTRODUCE A SLIGHT CHANCE OF
SHOWERS AND THUNDERSTORMS AT THE END OF THE PERIOD MONDAY AND
TUESDAY. FORCING SHOULD BE LIMITED TO WEAK SURFACE TROUGHINESS...SEA
BREEZE...AND/OR WEAK MID-LEVEL PVA AT TIMES...WHICH MAY BE ENOUGH
FOR ISOLATED SHOWERS AND THUNDERSTORMS IN A RELATIVELY MOIST AIR
MASS. 1000-850MB THICKNESSES GRADUALLY RISE...WHICH...ALONG WITH MOS
GUIDANCE...WOULD SUGGEST HIGHS RISING TO AT OR ABOVE NORMAL BY
SUNDAY. IF THE SURFACE DEW POINT IS A LITTLE HIGHER THAN FORECAST
PRIMARILY DUE TO SLIGHTLY LESS MIXING...MAXIMUM AFTERNOON HEAT
INDICES COULD RISE TO AROUND 100 BY MONDAY.
&&
.AVIATION /17Z TUESDAY THROUGH SUNDAY/...
AS OF 1210 PM TUESDAY...
A SURFACE COLD FRONT SLOWLY ADVANCING SOUTHEASTWARD WILL INTERACT
WITH THE MOIST AND SLIGHTLY UNSTABLE AIR MASS TO TRIGGER NUMEROUS
SHOWERS AND SCATTERED THUNDERSTORMS ACROSS CENTRAL NC LATER THIS
AFTERNOON THROUGH TONIGHT. THE SHOWER AND THUNDERSTORM COVERAGE IS
EXPECTED TO BE GREATEST BETWEEN 4 PM AND 10 PM. THE CONVECTIVE
ACTIVITY WILL CREATE WIDESPREAD MVFR CEILINGS/VISIBILITY WITH
POCKETS OF IFR CEILING/VISIBILITY IN THE HEAVIER SHOWERS.
THE COLD FRONT SHOULD CROSS THE TRIAD TERMINALS AROUND 10 PM...THE
KRDU/KRWI TERMINALS BETWEEN 1 AM AND 3 AM...AND THE KFAY VICINITY
BETWEEN 3-5 AM. AHEAD THE BOUNDARY EXPECT IFR CEILINGS ALONG WITH A
FEW SHOWERS. THE PASSAGE OF THE FRONT WILL BE NOTED BY SURFACE WINDS
VEERING FROM THE SW TO THE NORTH-NORTHWEST.
AVIATION CONDITIONS WILL BEGIN TO IMPROVE WEDNESDAY MORNING AS DRIER
MORE STABLE AIR FLOWS INTO THE REGION BEHIND THE EXITING FRONT.
EXPECT A RETURN TO VFR CONDITIONS THOUGH A STRATOCU DECK WILL LIKELY
DEVELOP WEDNESDAY AFTERNOON WITH BASES 3000-4000FT.
HIGH PRESSURE WILL BUILD INTO AND LINGER OVER CENTRAL NC WEDNESDAY
NIGHT THROUGH THE WEEKEND. THIS WEATHER SYSTEM WILL BRING DRY AND
STABLE CONDITIONS LEADING TO VFR PARAMETERS. THE EXCEPTION WILL BE A
BRIEF PERIOD OF MVFR VISIBILITY DUE TO FOG...MAINLY IN THE COASTAL
PLAIN.
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...WSS
NEAR TERM...WSS
SHORT TERM...WSS
LONG TERM...DJF
AVIATION...WSS
AREA FORECAST DISCUSSION
NWS BISMARCK ND
941 PM CDT WED JUN 19 2013
.UPDATE...
ISSUED AT 941 PM CDT WED JUN 19 2013
QUICK UPDATE TO CANCEL THE WIND ADVISORY IN THE SOUTHWEST AS SOUTHEAST
WINDS HAVE DECREASED TO LESS THAN WIND ADVISORY CRITERIA.
UPDATE ISSUED AT 920 PM CDT WED JUN 19 2013
LATEST RADAR IMAGERY SHOWS CONVECTION REMAINING ISOLATED AND
CONFINED TO EAST CENTRAL NORTH DAKOTA. THE 00Z NAM AND LATEST RAP
BOTH APPEAR TO HAVE A BETTER HANDLE ON WHAT HAS AND HAS NOT
DEVELOPED...VERSUS THE HRRR WHICH HAS BEEN OVER FORECASTING THE
DEVELOPMENT OF CONVECTION THIS EVENING.
USING THE 00Z NAM AND LATEST RAP MODELS...THE MAIN SHORTWAVE NOW
ROTATING INTO NORTHEAST IDAHO AND PRODUCING THE CONVECTIVE AREA IN
CENTRAL MONTANA WILL SHIFT A BIT FURTHER EAST INTO NORTHWEST NORTH
DAKOTA AFTER 06Z...WITH THE NAM ADVERTISING AN AREA OF CONVECTION
FROM CROSBY TO WILLISTON SOUTH TO DICKINSON FROM 06Z TO 09Z...AND
INTO BISMARCK BETWEEN 09Z AND 12Z THURSDAY. HOWEVER THE RAP
SUGGESTS THAT IT MAY NOT BE AS WIDESPREAD. STILL QUITE A BIT OF
UNCERTAINTY PAST 06Z AND WHAT WILL EVENTUALLY EVOLVE...THUS MADE
MINOR CHANGES TO POPS LATER TONIGHT. HOWEVER HAVE SCALED BACK
POPS THROUGH 06Z BASED ON THE CURRENT TRENDS. WILL CONTINUE TO
FOLLOW SPC ON THE SEVERE AREA AND MONITOR THE CONVECTION AS IT
ENTERS EASTERN MONTANA LATER THIS EVENING.
UPDATE ISSUED AT 618 PM CDT WED JUN 19 2013
CURRENT SATELLITE IMAGERY SHOWS A MID LEVEL SHORTWAVE ROTATING
NEAR SHIELDS IN SIOUX COUNTY WITH RADAR CONTINUING TO INDICATE AN
AREA OF SHOWERS AND ISOLATED THUNDERSTORMS WITH THIS WAVE. NOTHING
SEVERE AS OF YET WITH WEAK SHEAR...SFC TO 6KM SHEAR VALUES WELL
LESS THAN 30KT. THUS DESPITE HIGH REFLECTIVITY`S LOW TO MID
LEVELS...THEY HAVE NOT BEEN ABLE TO REACH MUCH HIGHER TO PRODUCE SEVERE
CRITERIA. HAVE ADJUSTED HOURLY TEMPERATURES IN THIS AREA WITH
COOLER READINGS OVER THE NEXT FEW HOURS. THIS SHORTWAVE WILL
CONTINUE TO MOVE NORTHEAST INTO THE SOUTHERN JAMES RIVER VALLEY
BUT NOT EXPECTING ANYTHING SEVERE WITH IT. AN ISOLATED
THUNDERSTORM WAS ALSO NOTED JUST SOUTHEAST OF KENMARE MOVING
NORTHWEST AND WILL CONTINUE TO MONITOR IT.
FURTHER WEST...STRONG SOUTHEASTERLY LOW LEVEL FLOW AND STRONG
SOUTHWEST WIND ALOFT ARE RESULTING IN SFC TO 6KM SHEAR VALUES OF
40KT IN FAR SOUTHWEST NORTH DAKOTA. SFC MAP AND SATELLITE IMAGERY
DEPICT A WARM FRONT IN CENTRAL SOUTH DAKOTA WITH A SMALL CUMULUS
FIELD SOUTHWEST...AND IN NORTHWEST NORTH DAKOTA. THIS WILL BE
WATCHED CLOSELY THIS EVENING FOR THUNDERSTORM DEVELOPMENT. THE
12Z WRF DID PICK UP ON THE SIOUX COUNTY CONVECTION MENTIONED ABOVE
FOR THIS EVENING...AND IT INDICATES THAT A LINE OF CONVECTION
WILL FORM IN EASTERN MONTANA AND WESTERN NORTH DAKOTA SHORTLY
AFTER 00Z. THE HRRR AND RAP DELAY THE LINE UNTIL AROUND 06Z...AND
THEN RAMP UP CONVECTION IN NORTHWEST NORTH DAKOTA THEREAFTER. ADDITIONAL
CONVECTION IS FOREACST TO INITIATE AND EXTEND INTO THE JAMES RIVER
VALLEY AFTER 06Z...ESSENTIALLY RESULTING IN A NORTHWEST TO
SOUTHEAST CONVECTION LINE ALONG THE WARM FRONTAL BOUNDARY.
FOR THIS EVENING...ANY AREA IS PRONE TO CONVECTION...AND WILL
CONTINUOUSLY MONITOR FOR INITIAL SIGNS. HOWEVER MORE CONFIDENT
WITH SEVERE WEATHER DEVELOPMENT WEST AND NORTHWEST...WITH BETTER
SHEAR VALUES AND CLOSER TO SHORTWAVE ENERGY EJECTING FROM IDAHO
INTO MONTANA THROUGH MOST OF THE NIGHT. THIS REMAINS IN LINE WITH
THE CURRENT FORECAST AND SPC DAY ONE OUTLOOK. MINIMAL CHANGES TO
CURRENT EVENING/OVERNIGHT FORECAST. WIND ADVISORY CONTINUES IN THE
SOUTHWEST THROUGH EARLY EVENING.
&&
.SHORT TERM...(THIS EVENING THROUGH THURSDAY)
ISSUED AT 333 PM CDT WED JUN 19 2013
MAIN CONCERNS THIS FORECAST INCLUDE THUNDERSTORMS...THEIR SEVERE
POTENTIAL AND POSSIBLE HEAVY RAIN. LATE THIS AFTERNOON AN
ELEVATED MIXED LAYER FROM EASTERN MONTANA INTO WESTERN NORTH
DAKOTA IS PROVIDING A SIGNIFICANT CAP. TO THE EAST OF THIS A
MOISTURE PLUME EXTENDS FROM EASTERN NORTH DAKOTA THROUGH THE
NORTH CENTRAL SUPPORTING WEAK CONVECTION BUT WITH LITTLE WIND SHEAR
TO SUPPORT CONTINUING DEVELOPMENT. SO WILL BE WAITING FOR THE
A STRONGER SHORTWAVE ACROSS WYOMING AND MONTANA TO ENTER THE
PICTURE LATER THIS EVENING AND OVERNIGHT. THIS WILL SUPPORT MORE
WIDESPREAD THUNDERSTORMS...AND CURRENT THINKING IS A LINE OF
STORMS CAPABLE OF SEVERE WINDS MAY DEVELOP ACROSS MONTANA AND
ENTER THE NORTHWEST INTO PORTIONS OF THE NORTH CENTRAL LATE
EVENING OR AFTER MIDNIGHT. ABOVE NORMAL MOISTURE IS AVAILABLE...
WITH PWATS SIGNIFICANTLY ABOVE NORMAL SUGGESTING THAT HEAVY RAIN
IS POSSIBLE. THE ONE FACTOR LIMITING FLASH FLOOD PRODUCING RAINS
MAY BE THE EXPECTED FAST MOVEMENT OF THE THUNDERSTORMS.
ON THURSDAY...THE EXPECTED REMNANTS OF OVERNIGHT CONVECTION WILL
BE IN CENTRAL NORTH DAKOTA. ANOTHER ROUND OF SEVERE STORMS EXPECTED
TO PICK UP STEAM LATE IN THE AFTERNOON AND EVENING.
.LONG TERM...(THURSDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 333 PM CDT WED JUN 19 2013
THE MAIN FORECAST CONCERNS IN THE LONG TERM PERIOD ARE SEVERE
WEATHER POTENTIAL...HEAVY RAIN POTENTIAL...AND TIMING ISSUES THROUGH
SATURDAY. THE UPPER LEVEL LOW/TROUGH REMAINS IN PLACE OVER THE
ROCKIES THROUGH SATURDAY...THEN THE MODELS BEGIN TO MOVE THE UPPER
LOW NORTHEASTWARD TOWARDS SOUTHERN SASKATCHEWAN/MANITOBA
SATURDAY/SATURDAY NIGHT/SUNDAY. CHANCE OF SHOWERS AND THUNDERSTORMS
INTO EARLY NEXT WEEK WITH GENERAL SOUTHWEST UPPER LEVEL FLOW.
THURSDAY...STRONG TO POTENTIALLY SEVERE STORMS FROM AN ORGANIZED
STORM CLUSTER MAY PERSIST ACROSS NORTHERN COUNTIES THURSDAY
MORNING...AND STORM RE-INTENSIFICATION IS EXPECTED DURING THE
AFTERNOON/EVENING HOURS ALONG A STRONG MOISTURE CONVERGENCE AXIS
WITH DEWPOINTS IN THE UPPER 60S AND PWAT VALUES APPROACHING 2
INCHES. BY EARLY THURSDAY EVENING THE NAM AND GFS ARE IN AGREEMENT
REGARDING THE POSITION OF THE SURFACE TROUGH...ROUGHLY FROM NEAR
BOTTINEAU/MINOT TO BETWEEN BISMARCK AND JAMESTOWN. THE EUROPEAN
MODEL IS A BIT SLOWER...DEPICTING THE FRONT FROM NEAR STANLEY TO
NEAR BISMARCK. FELT CONFIDENT ENOUGH THAT THE FAR SOUTHWEST CORNER
OF THE STATE WOULD BE FREE OF THUNDERSTORMS THURSDAY EVENING...AND
KEPT BEST CHANCES OF THUNDERSTORMS FROM THE BOTTINEAU/TURTLE
MOUNTAINS TO STEELE AND THE JAMES RIVER VALLEY WITH "LIKELY"
CHANCES. SEVERE PARAMETERS CONTINUE ALONG AND EAST OF THE FRONT.
CAPE VALUES UP TO 2500 WITH 0-6KM BULK SHEAR VALUES UP TO 40-45.
BY MIDNIGHT/1AM (06Z FRI)...THE GFS IS FASTEST - DEPICTING THE FRONT
OVER THE RED RIVER VALLEY - AND THE NAM/EC KEEP IT IN OR JUST EAST
OF THE JAMES RIVER VALLEY. REGARDLESS...CHANCES OF PRECIPITATION
FALL IN CENTRAL NORTH DAKOTA WITH THE SURFACE FRONT EXITING THE AREA
AND UPPER LEVEL SUPPORT WEAKENING. HOWEVER ANOTHER UPPER LEVEL
IMPULSE APPROACHES SOUTHWESTERN NORTH DAKOTA FROM WYOMING. BULK
SHEAR INCREASES WITH MODERATE INCREASES IN CAPE...AND KEPT A SLIGHT
CHANCE IN THE WEST.
FOR FRIDAY...TODAY`S MODELS DID NOT SET UP A HEAVY RAIN
EVENT...INSTEAD SEVERAL UPPER LEVEL IMPULSES MOVE THROUGH THE STATE
ON THE SOUTHWEST FLOW ALOFT...BUT THE MODELS DEVELOP THE SURFACE LOW
FARTHER SOUTH IN THE SOUTHERN PLAINS. KEPT GOOD CHANCES OF
PRECIPITATION FOR FRIDAY AND FRIDAY NIGHT. SEVERE PARAMETERS STILL
IN PLACE.
SATURDAY THE MODELS DEVELOP THE SURFACE LOW FARTHER NORTH WITH THE
UPPER LEVEL LOW/TROUGH MOVING NORTHEASTWARD ACROSS MONTANA INTO
WESTERN NORTH DAKOTA AND INTO SOUTHEAST SASKATCHEWAN. THIS WOULD SET
UP A WIDESPREAD MODERATE TO HEAVY RAIN EVENT...BUT MODELS ARE NOT IN
AGREEMENT FOR PLACEMENT AND TIMING.
NEAR SEASONAL TEMPS ARE EXPECTED THROUGH THE WEEKEND...FOLLOWED BY
SOME WARMING EARLY NEXT WEEK. HIGHS 70-80 THROUGH THE WEEKEND...AND
LOW TO MID 80S EARLY NEXT WEEK.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z THURSDAY EVENING)
ISSUED AT 618 CDT WED JUN 19 2013
MAINLY VFR CIGS/VSBYS THROUGH 06Z THURSDAY...WITH AN INCREASING
THREAT FOR SHOWERS AND THUNDERSTORMS WEST OVERNIGHT AND CENTRAL
THURSDAY. WITH ANY HEAVY THUNDERSTORMS...EXPECT BRIEF PERIODS OF
MVFR CIGS/VSBYS. PREDOMINANT SHOWERS AND THUNDERSTORMS HAVE BEEN
TO THE 00Z FORECASTS LATE WEDNESDAY NIGHT THROUGH THURSDAY.
&&
.HYDROLOGY...
ISSUED AT 333 PM CDT WED JUN 19 2013
THE THREAT FOR HEAVY RAIN EXISTS WITH THE EXPECTED THUNDERSTORMS
LATE TONIGHT...THURSDAY...THURSDAY NIGHT AND FRIDAY. THE PRECIPITABLE
WATER (PWAT) IS MUCH ABOVE NORMAL FOR THIS TIME OF YEAR. IF
THUNDERSTORMS FORM AS EXPECTED...THE BEST CHANCE FOR AN INCH OR
MORE OF RAINFALL WILL BE FROM FAR NORTHWEST...NORTH CENTRAL
THROUGH THE NORTHERN JAMES RIVER VALLEY. ONE TO TWO INCHES OF
RAIN IN THIS TWO DAY PERIOD IS POSSIBLE WITH MULTIPLE LINES OF
THUNDERSTORMS. THE ONE FACTOR THAT MAY LIMIT THE FLASH FLOOD
POTENTIAL WILL BE SIGNIFICANT MOVEMENT OF THE STORMS. ALSO THE
SURFACE MOISTURE...WHILE BEING HIGH...HAS HAD SOME TIME O DRY OUT
RECENTLY. RAINFALL AMOUNTS OF ONE TO 2 INCHES SHOULD BE ABLE TO BE
ABSORBED...ALTHOUGH MORE THAN TWO INCHES WOULD LIKELY CAUSE SOME
PROBLEMS.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...KS
SHORT TERM...WAA
LONG TERM...JV
AVIATION...KS
HYDROLOGY...WAA
AREA FORECAST DISCUSSION
NWS BISMARCK ND
920 PM CDT WED JUN 19 2013
.UPDATE...
ISSUED AT 920 PM CDT WED JUN 19 2013
LATEST RADAR IMAGERY SHOWS CONVECTION REMAINING ISOLATED AND
CONFINED TO EAST CENTRAL NORTH DAKOTA. THE 00Z NAM AND LATEST RAP
BOTH APPEAR TO HAVE A BETTER HANDLE ON WHAT HAS AND HAS NOT
DEVELOPED...VERSUS THE HRRR WHICH HAS BEEN OVER FORECASTING THE
DEVELOPMENT OF CONVECTION THIS EVENING.
USING THE 00Z NAM AND LATEST RAP MODELS...THE MAIN SHORTWAVE NOW
ROTATING INTO NORTHEAST IDAHO AND PRODUCING THE CONVECTIVE AREA IN
CENTRAL MONTANA WILL SHIFT A BIT FURTHER EAST INTO NORTHWEST NORTH
DAKOTA AFTER 06Z...WITH THE NAM ADVERTISING AN AREA OF CONVECTION
FROM CROSBY TO WILLISTON SOUTH TO DICKINSON FROM 06Z TO 09Z...AND
INTO BISMARCK BETWEEN 09Z AND 12Z THURSDAY. HOWEVER THE RAP
SUGGESTS THAT IT MAY NOT BE AS WIDESPREAD. STILL QUITE A BIT OF
UNCERTAINTY PAST 06Z AND WHAT WILL EVENTUALLY EVOLVE...THUS MADE
MINOR CHANGES TO POPS LATER TONIGHT. HOWEVER HAVE SCALED BACK
POPS THROUGH 06Z BASED ON THE CURRENT TRENDS. WILL CONTINUE TO
FOLLOW SPC ON THE SEVERE AREA AND MONITOR THE CONVECTION AS IT
ENTERS EASTERN MONTANA LATER THIS EVENING.
UPDATE ISSUED AT 618 PM CDT WED JUN 19 2013
CURRENT SATELLITE IMAGERY SHOWS A MID LEVEL SHORTWAVE ROTATING
NEAR SHIELDS IN SIOUX COUNTY WITH RADAR CONTINUING TO INDICATE AN
AREA OF SHOWERS AND ISOLATED THUNDERSTORMS WITH THIS WAVE. NOTHING
SEVERE AS OF YET WITH WEAK SHEAR...SFC TO 6KM SHEAR VALUES WELL
LESS THAN 30KT. THUS DESPITE HIGH REFLECTIVITY`S LOW TO MID
LEVELS...THEY HAVE NOT BEEN ABLE TO REACH MUCH HIGHER TO PRODUCE SEVERE
CRITERIA. HAVE ADJUSTED HOURLY TEMPERATURES IN THIS AREA WITH
COOLER READINGS OVER THE NEXT FEW HOURS. THIS SHORTWAVE WILL
CONTINUE TO MOVE NORTHEAST INTO THE SOUTHERN JAMES RIVER VALLEY
BUT NOT EXPECTING ANYTHING SEVERE WITH IT. AN ISOLATED
THUNDERSTORM WAS ALSO NOTED JUST SOUTHEAST OF KENMARE MOVING
NORTHWEST AND WILL CONTINUE TO MONITOR IT.
FURTHER WEST...STRONG SOUTHEASTERLY LOW LEVEL FLOW AND STRONG
SOUTHWEST WIND ALOFT ARE RESULTING IN SFC TO 6KM SHEAR VALUES OF
40KT IN FAR SOUTHWEST NORTH DAKOTA. SFC MAP AND SATELLITE IMAGERY
DEPICT A WARM FRONT IN CENTRAL SOUTH DAKOTA WITH A SMALL CUMULUS
FIELD SOUTHWEST...AND IN NORTHWEST NORTH DAKOTA. THIS WILL BE
WATCHED CLOSELY THIS EVENING FOR THUNDERSTORM DEVELOPMENT. THE
12Z WRF DID PICK UP ON THE SIOUX COUNTY CONVECTION MENTIONED ABOVE
FOR THIS EVENING...AND IT INDICATES THAT A LINE OF CONVECTION
WILL FORM IN EASTERN MONTANA AND WESTERN NORTH DAKOTA SHORTLY
AFTER 00Z. THE HRRR AND RAP DELAY THE LINE UNTIL AROUND 06Z...AND
THEN RAMP UP CONVECTION IN NORTHWEST NORTH DAKOTA THEREAFTER. ADDITIONAL
CONVECTION IS FOREACST TO INITIATE AND EXTEND INTO THE JAMES RIVER
VALLEY AFTER 06Z...ESSENTIALLY RESULTING IN A NORTHWEST TO
SOUTHEAST CONVECTION LINE ALONG THE WARM FRONTAL BOUNDARY.
FOR THIS EVENING...ANY AREA IS PRONE TO CONVECTION...AND WILL
CONTINUOUSLY MONITOR FOR INITIAL SIGNS. HOWEVER MORE CONFIDENT
WITH SEVERE WEATHER DEVELOPMENT WEST AND NORTHWEST...WITH BETTER
SHEAR VALUES AND CLOSER TO SHORTWAVE ENERGY EJECTING FROM IDAHO
INTO MONTANA THROUGH MOST OF THE NIGHT. THIS REMAINS IN LINE WITH
THE CURRENT FORECAST AND SPC DAY ONE OUTLOOK. MINIMAL CHANGES TO
CURRENT EVENING/OVERNIGHT FORECAST. WIND ADVISORY CONTINUES IN THE
SOUTHWEST THROUGH EARLY EVENING.
&&
.SHORT TERM...(THIS EVENING THROUGH THURSDAY)
ISSUED AT 333 PM CDT WED JUN 19 2013
MAIN CONCERNS THIS FORECAST INCLUDE THUNDERSTORMS...THEIR SEVERE
POTENTIAL AND POSSIBLE HEAVY RAIN. LATE THIS AFTERNOON AN
ELEVATED MIXED LAYER FROM EASTERN MONTANA INTO WESTERN NORTH
DAKOTA IS PROVIDING A SIGNIFICANT CAP. TO THE EAST OF THIS A
MOISTURE PLUME EXTENDS FROM EASTERN NORTH DAKOTA THROUGH THE
NORTH CENTRAL SUPPORTING WEAK CONVECTION BUT WITH LITTLE WIND SHEAR
TO SUPPORT CONTINUING DEVELOPMENT. SO WILL BE WAITING FOR THE
A STRONGER SHORTWAVE ACROSS WYOMING AND MONTANA TO ENTER THE
PICTURE LATER THIS EVENING AND OVERNIGHT. THIS WILL SUPPORT MORE
WIDESPREAD THUNDERSTORMS...AND CURRENT THINKING IS A LINE OF
STORMS CAPABLE OF SEVERE WINDS MAY DEVELOP ACROSS MONTANA AND
ENTER THE NORTHWEST INTO PORTIONS OF THE NORTH CENTRAL LATE
EVENING OR AFTER MIDNIGHT. ABOVE NORMAL MOISTURE IS AVAILABLE...
WITH PWATS SIGNIFICANTLY ABOVE NORMAL SUGGESTING THAT HEAVY RAIN
IS POSSIBLE. THE ONE FACTOR LIMITING FLASH FLOOD PRODUCING RAINS
MAY BE THE EXPECTED FAST MOVEMENT OF THE THUNDERSTORMS.
ON THURSDAY...THE EXPECTED REMNANTS OF OVERNIGHT CONVECTION WILL
BE IN CENTRAL NORTH DAKOTA. ANOTHER ROUND OF SEVERE STORMS EXPECTED
TO PICK UP STEAM LATE IN THE AFTERNOON AND EVENING.
.LONG TERM...(THURSDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 333 PM CDT WED JUN 19 2013
THE MAIN FORECAST CONCERNS IN THE LONG TERM PERIOD ARE SEVERE
WEATHER POTENTIAL...HEAVY RAIN POTENTIAL...AND TIMING ISSUES THROUGH
SATURDAY. THE UPPER LEVEL LOW/TROUGH REMAINS IN PLACE OVER THE
ROCKIES THROUGH SATURDAY...THEN THE MODELS BEGIN TO MOVE THE UPPER
LOW NORTHEASTWARD TOWARDS SOUTHERN SASKATCHEWAN/MANITOBA
SATURDAY/SATURDAY NIGHT/SUNDAY. CHANCE OF SHOWERS AND THUNDERSTORMS
INTO EARLY NEXT WEEK WITH GENERAL SOUTHWEST UPPER LEVEL FLOW.
THURSDAY...STRONG TO POTENTIALLY SEVERE STORMS FROM AN ORGANIZED
STORM CLUSTER MAY PERSIST ACROSS NORTHERN COUNTIES THURSDAY
MORNING...AND STORM RE-INTENSIFICATION IS EXPECTED DURING THE
AFTERNOON/EVENING HOURS ALONG A STRONG MOISTURE CONVERGENCE AXIS
WITH DEWPOINTS IN THE UPPER 60S AND PWAT VALUES APPROACHING 2
INCHES. BY EARLY THURSDAY EVENING THE NAM AND GFS ARE IN AGREEMENT
REGARDING THE POSITION OF THE SURFACE TROUGH...ROUGHLY FROM NEAR
BOTTINEAU/MINOT TO BETWEEN BISMARCK AND JAMESTOWN. THE EUROPEAN
MODEL IS A BIT SLOWER...DEPICTING THE FRONT FROM NEAR STANLEY TO
NEAR BISMARCK. FELT CONFIDENT ENOUGH THAT THE FAR SOUTHWEST CORNER
OF THE STATE WOULD BE FREE OF THUNDERSTORMS THURSDAY EVENING...AND
KEPT BEST CHANCES OF THUNDERSTORMS FROM THE BOTTINEAU/TURTLE
MOUNTAINS TO STEELE AND THE JAMES RIVER VALLEY WITH "LIKELY"
CHANCES. SEVERE PARAMETERS CONTINUE ALONG AND EAST OF THE FRONT.
CAPE VALUES UP TO 2500 WITH 0-6KM BULK SHEAR VALUES UP TO 40-45.
BY MIDNIGHT/1AM (06Z FRI)...THE GFS IS FASTEST - DEPICTING THE FRONT
OVER THE RED RIVER VALLEY - AND THE NAM/EC KEEP IT IN OR JUST EAST
OF THE JAMES RIVER VALLEY. REGARDLESS...CHANCES OF PRECIPITATION
FALL IN CENTRAL NORTH DAKOTA WITH THE SURFACE FRONT EXITING THE AREA
AND UPPER LEVEL SUPPORT WEAKENING. HOWEVER ANOTHER UPPER LEVEL
IMPULSE APPROACHES SOUTHWESTERN NORTH DAKOTA FROM WYOMING. BULK
SHEAR INCREASES WITH MODERATE INCREASES IN CAPE...AND KEPT A SLIGHT
CHANCE IN THE WEST.
FOR FRIDAY...TODAY`S MODELS DID NOT SET UP A HEAVY RAIN
EVENT...INSTEAD SEVERAL UPPER LEVEL IMPULSES MOVE THROUGH THE STATE
ON THE SOUTHWEST FLOW ALOFT...BUT THE MODELS DEVELOP THE SURFACE LOW
FARTHER SOUTH IN THE SOUTHERN PLAINS. KEPT GOOD CHANCES OF
PRECIPITATION FOR FRIDAY AND FRIDAY NIGHT. SEVERE PARAMETERS STILL
IN PLACE.
SATURDAY THE MODELS DEVELOP THE SURFACE LOW FARTHER NORTH WITH THE
UPPER LEVEL LOW/TROUGH MOVING NORTHEASTWARD ACROSS MONTANA INTO
WESTERN NORTH DAKOTA AND INTO SOUTHEAST SASKATCHEWAN. THIS WOULD SET
UP A WIDESPREAD MODERATE TO HEAVY RAIN EVENT...BUT MODELS ARE NOT IN
AGREEMENT FOR PLACEMENT AND TIMING.
NEAR SEASONAL TEMPS ARE EXPECTED THROUGH THE WEEKEND...FOLLOWED BY
SOME WARMING EARLY NEXT WEEK. HIGHS 70-80 THROUGH THE WEEKEND...AND
LOW TO MID 80S EARLY NEXT WEEK.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z THURSDAY EVENING)
ISSUED AT 618 CDT WED JUN 19 2013
MAINLY VFR CIGS/VSBYS THROUGH 06Z THURSDAY...WITH AN INCREASING
THREAT FOR SHOWERS AND THUNDERSTORMS WEST OVERNIGHT AND CENTRAL
THURSDAY. WITH ANY HEAVY THUNDERSTORMS...EXPECT BRIEF PERIODS OF
MVFR CIGS/VSBYS. PREDOMINANT SHOWERS AND THUNDERSTORMS HAVE BEEN
TO THE 00Z FORECASTS LATE WEDNESDAY NIGHT THROUGH THURSDAY.
&&
.HYDROLOGY...
ISSUED AT 333 PM CDT WED JUN 19 2013
THE THREAT FOR HEAVY RAIN EXISTS WITH THE EXPECTED THUNDERSTORMS
LATE TONIGHT...THURSDAY...THURSDAY NIGHT AND FRIDAY. THE PRECIPITABLE
WATER (PWAT) IS MUCH ABOVE NORMAL FOR THIS TIME OF YEAR. IF
THUNDERSTORMS FORM AS EXPECTED...THE BEST CHANCE FOR AN INCH OR
MORE OF RAINFALL WILL BE FROM FAR NORTHWEST...NORTH CENTRAL
THROUGH THE NORTHERN JAMES RIVER VALLEY. ONE TO TWO INCHES OF
RAIN IN THIS TWO DAY PERIOD IS POSSIBLE WITH MULTIPLE LINES OF
THUNDERSTORMS. THE ONE FACTOR THAT MAY LIMIT THE FLASH FLOOD
POTENTIAL WILL BE SIGNIFICANT MOVEMENT OF THE STORMS. ALSO THE
SURFACE MOISTURE...WHILE BEING HIGH...HAS HAD SOME TIME O DRY OUT
RECENTLY. RAINFALL AMOUNTS OF ONE TO 2 INCHES SHOULD BE ABLE TO BE
ABSORBED...ALTHOUGH MORE THAN TWO INCHES WOULD LIKELY CAUSE SOME
PROBLEMS.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
WIND ADVISORY UNTIL 9 PM MDT THIS EVENING FOR NDZ031>033-040-041-
043-044.
&&
$$
UPDATE...KS
SHORT TERM...WAA
LONG TERM...JV
AVIATION...KS
HYDROLOGY...WAA
AREA FORECAST DISCUSSION
NWS BISMARCK ND
618 PM CDT WED JUN 19 2013
.UPDATE...
ISSUED AT 618 PM CDT WED JUN 19 2013
CURRENT SATELLITE IMAGERY SHOWS A MID LEVEL SHORTWAVE ROTATING
NEAR SHIELDS IN SIOUX COUNTY WITH RADAR CONTINUING TO INDICATE AN
AREA OF SHOWERS AND ISOLATED THUNDERSTORMS WITH THIS WAVE. NOTHING
SEVERE AS OF YET WITH WEAK SHEAR...SFC TO 6KM SHEAR VALUES WELL
LESS THAN 30KT. THUS DESPITE HIGH REFLECTIVITY`S LOW TO MID
LEVELS...THEY HAVE NOT BEEN ABLE TO REACH MUCH HIGHER TO PRODUCE SEVERE
CRITERIA. HAVE ADJUSTED HOURLY TEMPERATURES IN THIS AREA WITH
COOLER READINGS OVER THE NEXT FEW HOURS. THIS SHORTWAVE WILL
CONTINUE TO MOVE NORTHEAST INTO THE SOUTHERN JAMES RIVER VALLEY
BUT NOT EXPECTING ANYTHING SEVERE WITH IT. AN ISOLATED
THUNDERSTORM WAS ALSO NOTED JUST SOUTHEAST OF KENMARE MOVING
NORTHWEST AND WILL CONTINUE TO MONITOR IT.
FURTHER WEST...STRONG SOUTHEASTERLY LOW LEVEL FLOW AND STRONG
SOUTHWEST WIND ALOFT ARE RESULTING IN SFC TO 6KM SHEAR VALUES OF
40KT IN FAR SOUTHWEST NORTH DAKOTA. SFC MAP AND SATELLITE IMAGERY
DEPICT A WARM FRONT IN CENTRAL SOUTH DAKOTA WITH A SMALL CUMULUS
FIELD SOUTHWEST...AND IN NORTHWEST NORTH DAKOTA. THIS WILL BE
WATCHED CLOSELY THIS EVENING FOR THUNDERSTORM DEVELOPMENT. THE
12Z WRF DID PICK UP ON THE SIOUX COUNTY CONVECTION MENTIONED ABOVE
FOR THIS EVENING...AND IT INDICATES THAT A LINE OF CONVECTION
WILL FORM IN EASTERN MONTANA AND WESTERN NORTH DAKOTA SHORTLY
AFTER 00Z. THE HRRR AND RAP DELAY THE LINE UNTIL AROUND 06Z...AND
THEN RAMP UP CONVECTION IN NORTHWEST NORTH DAKOTA THEREAFTER. ADDITIONAL
CONVECTION IS FOREACST TO INITIATE AND EXTEND INTO THE JAMES RIVER
VALLEY AFTER 06Z...ESSENTIALLY RESULTING IN A NORTHWEST TO
SOUTHEAST CONVECTION LINE ALONG THE WARM FRONTAL BOUNDARY.
FOR THIS EVENING...ANY AREA IS PRONE TO CONVECTION...AND WILL
CONTINUOUSLY MONITOR FOR INITIAL SIGNS. HOWEVER MORE CONFIDENT
WITH SEVERE WEATHER DEVELOPMENT WEST AND NORTHWEST...WITH BETTER
SHEAR VALUES AND CLOSER TO SHORTWAVE ENERGY EJECTING FROM IDAHO
INTO MONTANA THROUGH MOST OF THE NIGHT. THIS REMAINS IN LINE WITH
THE CURRENT FORECAST AND SPC DAY ONE OUTLOOK. MINIMAL CHANGES TO
CURRENT EVENING/OVERNIGHT FORECAST. WIND ADVISORY CONTINUES IN THE
SOUTHWEST THROUGH EARLY EVENING.
&&
.SHORT TERM...(THIS EVENING THROUGH THURSDAY)
ISSUED AT 333 PM CDT WED JUN 19 2013
MAIN CONCERNS THIS FORECAST INCLUDE THUNDERSTORMS...THEIR SEVERE
POTENTIAL AND POSSIBLE HEAVY RAIN. LATE THIS AFTERNOON AN
ELEVATED MIXED LAYER FROM EASTERN MONTANA INTO WESTERN NORTH
DAKOTA IS PROVIDING A SIGNIFICANT CAP. TO THE EAST OF THIS A
MOISTURE PLUME EXTENDS FROM EASTERN NORTH DAKOTA THROUGH THE
NORTH CENTRAL SUPPORTING WEAK CONVECTION BUT WITH LITTLE WIND SHEAR
TO SUPPORT CONTINUING DEVELOPMENT. SO WILL BE WAITING FOR THE
A STRONGER SHORTWAVE ACROSS WYOMING AND MONTANA TO ENTER THE
PICTURE LATER THIS EVENING AND OVERNIGHT. THIS WILL SUPPORT MORE
WIDESPREAD THUNDERSTORMS...AND CURRENT THINKING IS A LINE OF
STORMS CAPABLE OF SEVERE WINDS MAY DEVELOP ACROSS MONTANA AND
ENTER THE NORTHWEST INTO PORTIONS OF THE NORTH CENTRAL LATE
EVENING OR AFTER MIDNIGHT. ABOVE NORMAL MOISTURE IS AVAILABLE...
WITH PWATS SIGNIFICANTLY ABOVE NORMAL SUGGESTING THAT HEAVY RAIN
IS POSSIBLE. THE ONE FACTOR LIMITING FLASH FLOOD PRODUCING RAINS
MAY BE THE EXPECTED FAST MOVEMENT OF THE THUNDERSTORMS.
ON THURSDAY...THE EXPECTED REMNANTS OF OVERNIGHT CONVECTION WILL
BE IN CENTRAL NORTH DAKOTA. ANOTHER ROUND OF SEVERE STORMS EXPECTED
TO PICK UP STEAM LATE IN THE AFTERNOON AND EVENING.
.LONG TERM...(THURSDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 333 PM CDT WED JUN 19 2013
THE MAIN FORECAST CONCERNS IN THE LONG TERM PERIOD ARE SEVERE
WEATHER POTENTIAL...HEAVY RAIN POTENTIAL...AND TIMING ISSUES THROUGH
SATURDAY. THE UPPER LEVEL LOW/TROUGH REMAINS IN PLACE OVER THE
ROCKIES THROUGH SATURDAY...THEN THE MODELS BEGIN TO MOVE THE UPPER
LOW NORTHEASTWARD TOWARDS SOUTHERN SASKATCHEWAN/MANITOBA
SATURDAY/SATURDAY NIGHT/SUNDAY. CHANCE OF SHOWERS AND THUNDERSTORMS
INTO EARLY NEXT WEEK WITH GENERAL SOUTHWEST UPPER LEVEL FLOW.
THURSDAY...STRONG TO POTENTIALLY SEVERE STORMS FROM AN ORGANIZED
STORM CLUSTER MAY PERSIST ACROSS NORTHERN COUNTIES THURSDAY
MORNING...AND STORM RE-INTENSIFICATION IS EXPECTED DURING THE
AFTERNOON/EVENING HOURS ALONG A STRONG MOISTURE CONVERGENCE AXIS
WITH DEWPOINTS IN THE UPPER 60S AND PWAT VALUES APPROACHING 2
INCHES. BY EARLY THURSDAY EVENING THE NAM AND GFS ARE IN AGREEMENT
REGARDING THE POSITION OF THE SURFACE TROUGH...ROUGHLY FROM NEAR
BOTTINEAU/MINOT TO BETWEEN BISMARCK AND JAMESTOWN. THE EUROPEAN
MODEL IS A BIT SLOWER...DEPICTING THE FRONT FROM NEAR STANLEY TO
NEAR BISMARCK. FELT CONFIDENT ENOUGH THAT THE FAR SOUTHWEST CORNER
OF THE STATE WOULD BE FREE OF THUNDERSTORMS THURSDAY EVENING...AND
KEPT BEST CHANCES OF THUNDERSTORMS FROM THE BOTTINEAU/TURTLE
MOUNTAINS TO STEELE AND THE JAMES RIVER VALLEY WITH "LIKELY"
CHANCES. SEVERE PARAMETERS CONTINUE ALONG AND EAST OF THE FRONT.
CAPE VALUES UP TO 2500 WITH 0-6KM BULK SHEAR VALUES UP TO 40-45.
BY MIDNIGHT/1AM (06Z FRI)...THE GFS IS FASTEST - DEPICTING THE FRONT
OVER THE RED RIVER VALLEY - AND THE NAM/EC KEEP IT IN OR JUST EAST
OF THE JAMES RIVER VALLEY. REGARDLESS...CHANCES OF PRECIPITATION
FALL IN CENTRAL NORTH DAKOTA WITH THE SURFACE FRONT EXITING THE AREA
AND UPPER LEVEL SUPPORT WEAKENING. HOWEVER ANOTHER UPPER LEVEL
IMPULSE APPROACHES SOUTHWESTERN NORTH DAKOTA FROM WYOMING. BULK
SHEAR INCREASES WITH MODERATE INCREASES IN CAPE...AND KEPT A SLIGHT
CHANCE IN THE WEST.
FOR FRIDAY...TODAY`S MODELS DID NOT SET UP A HEAVY RAIN
EVENT...INSTEAD SEVERAL UPPER LEVEL IMPULSES MOVE THROUGH THE STATE
ON THE SOUTHWEST FLOW ALOFT...BUT THE MODELS DEVELOP THE SURFACE LOW
FARTHER SOUTH IN THE SOUTHERN PLAINS. KEPT GOOD CHANCES OF
PRECIPITATION FOR FRIDAY AND FRIDAY NIGHT. SEVERE PARAMETERS STILL
IN PLACE.
SATURDAY THE MODELS DEVELOP THE SURFACE LOW FARTHER NORTH WITH THE
UPPER LEVEL LOW/TROUGH MOVING NORTHEASTWARD ACROSS MONTANA INTO
WESTERN NORTH DAKOTA AND INTO SOUTHEAST SASKATCHEWAN. THIS WOULD SET
UP A WIDESPREAD MODERATE TO HEAVY RAIN EVENT...BUT MODELS ARE NOT IN
AGREEMENT FOR PLACEMENT AND TIMING.
NEAR SEASONAL TEMPS ARE EXPECTED THROUGH THE WEEKEND...FOLLOWED BY
SOME WARMING EARLY NEXT WEEK. HIGHS 70-80 THROUGH THE WEEKEND...AND
LOW TO MID 80S EARLY NEXT WEEK.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z THURSDAY EVENING)
ISSUED AT 618 CDT WED JUN 19 2013
MAINLY VFR CIGS/VSBYS THROUGH 06Z THURSDAY...WITH AN INCREASING
THREAT FOR SHOWERS AND THUNDERSTORMS WEST OVERNIGHT AND CENTRAL
THURSDAY. WITH ANY HEAVY THUNDERSTORMS...EXPECT BRIEF PERIODS OF
MVFR CIGS/VSBYS. PREDOMINANT SHOWERS AND THUNDERSTORMS HAVE BEEN
TO THE 00Z FORECASTS LATE WEDNESDAY NIGHT THROUGH THURSDAY.
&&
.HYDROLOGY...
ISSUED AT 333 PM CDT WED JUN 19 2013
THE THREAT FOR HEAVY RAIN EXISTS WITH THE EXPECTED THUNDERSTORMS
LATE TONIGHT...THURSDAY...THURSDAY NIGHT AND FRIDAY. THE PRECIPITABLE
WATER (PWAT) IS MUCH ABOVE NORMAL FOR THIS TIME OF YEAR. IF
THUNDERSTORMS FORM AS EXPECTED...THE BEST CHANCE FOR AN INCH OR
MORE OF RAINFALL WILL BE FROM FAR NORTHWEST...NORTH CENTRAL
THROUGH THE NORTHERN JAMES RIVER VALLEY. ONE TO TWO INCHES OF
RAIN IN THIS TWO DAY PERIOD IS POSSIBLE WITH MULTIPLE LINES OF
THUNDERSTORMS. THE ONE FACTOR THAT MAY LIMIT THE FLASH FLOOD
POTENTIAL WILL BE SIGNIFICANT MOVEMENT OF THE STORMS. ALSO THE
SURFACE MOISTURE...WHILE BEING HIGH...HAS HAD SOME TIME O DRY OUT
RECENTLY. RAINFALL AMOUNTS OF ONE TO 2 INCHES SHOULD BE ABLE TO BE
ABSORBED...ALTHOUGH MORE THAN TWO INCHES WOULD LIKELY CAUSE SOME
PROBLEMS.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
WIND ADVISORY UNTIL 9 PM MDT THIS EVENING FOR NDZ031>033-040-041-
043-044.
&&
$$
UPDATE...KS
SHORT TERM...WAA
LONG TERM...JV
AVIATION...KS
HYDROLOGY...WAA
AREA FORECAST DISCUSSION
NWS WILMINGTON OH
157 AM EDT TUE JUN 18 2013
.SYNOPSIS...
AN UPPER LEVEL DISTURBANCE WILL MOVE ALONG AND SOUTH OF THE OHIO
RIVER TONIGHT INTO THE FIRST PART OF TUESDAY. LATER ON
TUESDAY...A COLD FRONT WILL SAG SOUTH ACROSS THE REGION. THIS
FRONT WILL INTERACT WITH ANOTHER UPPER LEVEL DISTURBANCE TO
CONTINUE THE THREAT FOR SHOWERS AND STORMS. BOTH SYSTEMS ARE
FORECAST TO EXIT THE REGION LATE TUESDAY NIGHT...ALLOWING
PRECIPITATION TO COME TO AN END AS HIGH PRESSURE BUILDS INTO THE
REGION.
&&
.NEAR TERM /UNTIL 6 AM THIS MORNING/...
IT WILL BE A DIFFICULT NEAR TERM FORECAST AS MODELS ARE HAVING A
TOUGH TIME HANDLING HOW FAR NORTH CURRENT SHOWERS AND THUNDERSTORMS
SOUTH OF THE OHIO RIVER WILL GET. HAVE USED A BLEND OF RADAR
TRENDS AND THE LATEST HRRR TO BRING LIKELY POPS ALONG AND SOUTH OF
THE RIVER WITH DECREASING CHANCES NORTH OF THE RIVER. THIS
ACTIVITY WAS BEING CAUSED BY AN APPROACHING UPPER LEVEL S/WV ALONG
WITH SOME 850 MB-700 MB DEFORMATION. SKIES SHOULD REMAIN CLOUDY
OVERNIGHT GIVEN CONSIDERABLE CONVECTIVE DEBRIS BLOW OFF. OVERNIGHT
LOWS WILL DROP INTO THE MID 60S FOR MOST LOCATIONS.
&&
.SHORT TERM /6 AM THIS MORNING THROUGH 6 PM WEDNESDAY/...
THE THREAT FOR SHOWERS AND THUNDERSTORMS WILL CONTINUE ON TUESDAY
AS ONE SHORT WAVE EXITS AND ANOTHER ONE APPROACHES FROM THE
NORTHWEST. AT THE SAME TIME... A COLD FRONT WILL SAG SOUTH INTO
THE REGION. THE HIGHEST CONCENTRATION OF STORMS MAY BE OVER
THE SOUTHEAST COUNTIES IN THE MORNING WHERE GREATEST FORCING AND
MOISTURE WILL COINCIDE WITH EXITING FIRST AFOREMENTIONED SHORT WAVE.
A FEW STORMS COULD BECOME SEVERE HELPED BY A MODERATE MID LEVEL
WESTERLY FLOW. THUNDERSTORMS WILL DIMINISH TUESDAY NIGHT WITH LOSS
OF DAYTIME HEATING AND AS THE COLD FRONT/SHORT WAVE TANDEM EXIT
SOUTHEAST. HIGHS TUESDAY WILL REACH THE LOW 80S WITH LOWS TUESDAY
NIGHT BACK INTO THE 60S.
&&
.LONG TERM /WEDNESDAY NIGHT THROUGH MONDAY/...
MID LEVEL RIDGE BUILDS INTO THE NATIONS MID SECTION AT MID WEEK
WITH FLOW BECOMING NORTHWESTERLY OVER THE OHIO VALLEY.
SURFACE HIGH PRESSURE TO BUILD SE BECOMING CENTERED OVER THE REGION
WEDNESDAY. THIS HIGH WILL PROVIDE DRY WEATHER CONDITIONS AND OFFER
TEMPERATURES A LTL BELOW NORMAL WEDNESDAY AND CLOSE TO NORMAL
THURSDAY.
MID LEVEL RIDGE AXIS TO SLIDE EAST INTO THE MID MS VALLEY BY THE END
OF THE WEEK. A SOUTHERLY LOW LEVEL FLOW WILL DEVELOP ON THE BACK
SIDE OF THIS RETREATING SFC HIGH PRESSURE FOR THE END OF THE WEEK.
THIS WILL ALLOW FOR A WARMING TREND FOR THE END OF THE WEEK INTO NEXT
WEEKEND. HIGHS ON FRIDAY ARE GENERALLY EXPECTED TO BE IN THE MIDDLE
80S.
SOME MODEL SOLN DIFFERENCES EXIST REGARDING HOW FAR EAST THE RIDGE
BUILDS AND RESULTANT...HEAT AND SUPPRESSION OF DEEP CONVECTION.
LATEST OPERATIONAL ECMWF/GFS WOULD SUGGEST THAT WIDESPREAD
CONVECTION WILL HOLD OFF THRU SATURDAY. WILL ALLOW SLIGHT CHC POPS
SATURDAY NIGHT AND LOW POP CHANCE TO DEVELOP SUNDAY WITH SOME
EVIDENCE THAT A THUNDERSTORM COMPLEX WILL DIVE SE INTO THE OHIO
VALLEY. SINCE A GOOD DEAL OF UNCERTAINTY EXISTS AT THIS TIMEFRAME
REGARDING TIMING AND PLACEMENT HAVE LIMITED POPS. SFC FRONT TO LAY
OUT ACRS SRN GREAT LAKES MONDAY. WILL CONTINUE A LOW POP CHC FOR
PRECIP WITH THE BEST CHANCE ACRS THE NORTH.
IN THE WARM SECTOR EXPECT HIGHS IN THE MID/UPR 80S BOTH SATURDAY/
SUNDAY AND INTO EARLY NEXT WEEK.
&&
.AVIATION /06Z TUESDAY THROUGH SATURDAY/...
FIRST OF TWO H5 S/W THAT WILL AFFECT THE TAFS DURING THE TAF
PERIOD IS SWINGING ACROSS KY ATTM. THIS ENERGY IS HELPING TO
DRIVE THE CONVECTION ACROSS KY AND SRN OHIO. BEST LIFT FROM THIS
S/W WILL WORK E QUICKLY AT THE BEGINNING OF THE PERIOD. THE
CONVECTION IS WANING...SO IT LOOKS LIKE THE TAF WILL REMAIN DRY
FOR THE FIRST PART OF THE PERIOD.
MODELS BRING SECOND S/WV IN THE NORTHWEST FLOW ALOFT TO THE REGION
BETWEEN AROUND 00Z. THIS FEATURE...ALONG WITH LINGERING
INSTABILITY NEAR AND BEHIND A STALLED FRONT WILL TRIGGER ANOTHER
ROUND OF CONVECTION. KEPT THE MENTION OF VCTS/CB AT THE TERMINALS
STARTING AT 18Z. THE BEST CHANCE OF PCPN MIGHT BE AROUND 00Z AS
THE BEST LIFT FROM THE S/W MOVES. THAT IS A LITTLE FAR OUT TO ADD
A TEMPO RIGHT NOW. FOR THE 30 HOUR TAF AT KCVG...S/WV SHOULD BE
MOVING PAST BY 06Z...SO BROUGHT THE PCPN TO AN END AT 06Z.
OUTLOOK...THUNDERSTORMS POSSIBLE THIS EVENING.
&&
.ILN WATCHES/WARNINGS/ADVISORIES...
OH...NONE.
KY...NONE.
IN...NONE.
&&
$$
SYNOPSIS...CONIGLIO/HICKMAN
NEAR TERM...CONIGLIO/HICKMAN
SHORT TERM...CONIGLIO
LONG TERM...AR
AVIATION...SITES
AREA FORECAST DISCUSSION
NWS NORMAN OK
1155 PM CDT MON JUN 17 2013
.AVIATION...
CONVECTION HAS DEVELOPED IN THE VICINITY OF KSPS WITHIN THE PAST
HALF HOUR. HRRR SUGGESTS THAT THIS MAY DISSIPATE QUICKLY AND WILL
LOOK AT THE STATUS OF THIS WHEN IT THE TAFS ARE ISSUED. STRATUS
REDEVELOPMENT LOOKS LESS LIKELY IN THE LATEST MODEL RUNS AND WILL
NOT INCLUDE IT IN THE 06Z TAFS DUE TO RELATIVELY LOW
PROBABILITY... BUT IT IS NOT OUT OF THE QUESTION... ESPECIALLY IN
THE SOUTHWEST.
&&
.PREV DISCUSSION... /ISSUED 344 PM CDT MON JUN 17 2013/
DISCUSSION...
UNSEASONABLY COOL CONDITIONS ARE PRESENT THIS AFTERNOON BEHIND A
COLD FRONT DUE TO WIDESPREAD RAINFALL LAST NIGHT AND PERSISTENT
STRATUS THROUGHOUT MOST OF THE DAY. A FEW AREAS OF SHOWERS ARE
TRYING TO NUDGE INTO THE NE FA AROUND A MCV...BUT ANY OTHER MOIST
CONVECTION REMAINS SOUTH OF OUR FA ACROSS N TX. ALTHOUGH SKIES
WILL INITIALLY BEGIN TO CLEAR THIS EVENING...STRATUS WILL LIKELY
RETURN TONIGHT. IN ADDITION...CONVECTION ACROSS WEST TEXAS MAY TRY
TO MAKE ITS WAY INTO OUR TX ZONES LATE TONIGHT. HOWEVER...FEEL
CONFIDENT THAT MOST OF THIS SHOULD REMAIN JUST SOUTH OF OUR FA SO
HAVE ISOLATED HIGHEST POPS TO OUR SOUTHWESTERN BORDERS. A SFC HIGH
UNDER MID LEVEL NW FLOW WILL MOVE OVER THE MIDWEST AND NE OK
TOMORROW KEEPING HIGH TEMPS BELOW AVG. POPS WILL RETURN TO THE
FORECAST LATE TOMORROW THROUGH MID DAY WED AS SHORTWAVE TROUGH
MOVING OUT OF THE ROCKIES ROUNDS THE MID LEVEL RIDGE AXIS. DO NOT
EXPECT A LOT OF PRECIP WITH THIS FEATURE...BUT THINK HIGH CHC POPS
APPEAR REASONBLE FOR MOST LOCATIONS JUST EAST OF THE RIDGE WITH
DEEPER MOISTURE MOVING BACK INTO PLACE.
SIGNFICANT POPS WILL COME TO AN END AFTER WED...BUT DID MENTION
SOME SLIGHT TO LOW END CHCS FOR THURS AM AS ANOTHER MID LEVEL
SHORTWAVE TROUGH TRAVERSES THE NORTHERN ZONES. THIS WILL ALSO BE
TRUE ACROSS THE NW BY FRI AS THE RIDGE SLIDES EAST ALLOWING A FEW
MORE WEAK SHORTWAVE TROUGHS TO MOVE OVER THE PANHANDLE
REGION...AND PERHAPS EVEN AS FAR SOUTH AS CENTRAL OK BY SAT AM.
OTHER THAN THESE LOW END POPS...THE GENERAL TREND WILL BE WARMER
TEMPS THURS-SAT AS THE SUBTROPICAL RIDGE AXIS REMAINS IN PLACE
FROM WEST TX THROUGH AT LEAST SW OK.
&&
.PRELIMINARY POINT TEMPS/POPS...
OKLAHOMA CITY OK 68 85 69 84 / 10 10 50 50
HOBART OK 68 88 68 90 / 10 20 30 30
WICHITA FALLS TX 71 90 70 93 / 20 20 30 30
GAGE OK 64 85 65 87 / 20 20 40 40
PONCA CITY OK 67 86 68 84 / 10 20 40 40
DURANT OK 70 88 70 89 / 10 20 40 40
&&
.OUN WATCHES/WARNINGS/ADVISORIES...
OK...NONE.
TX...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS MEDFORD OR
851 AM PDT TUE JUN 18 2013
.DISCUSSION...SATELLITE IMAGERY SHOWS FRONTAL CLOUD BANDS BLANKET
MOST OF OUR EASTERN DISTRICT WITH MOSTLY CLOUDY SKY ACROSS EASTER
DOUGLAS COUNTY AND JACKSON COUNTY. ONSHORE FLOW IS BRINGING MORE
CLOUDS TO THE COAST AND IN THE LAST FEW HOURS CLOUDS HAVE SPREAD
INTO WESTERN JOSEPHINE COUNTY. HAVE UPDATED THE SKY GRIDS TO
ACCOUNT FOR AREAS OF CLEAR SKY THIS MORNING ON THE WEST SIDE. COLD
AIR ALOFT WILL ALSO BE MOVING INTO OUR FORECAST AREA TODAY AND WE
CAN EXPECT INSTABILITY SHOWERS TO DEVELOP THIS AFTERNOON. LIFTED
INDICES ARE NOT VERY HIGH AND THUNDERSTORM COVERAGE SHOULD BE
ISOLATED. COOLER THAN NORMAL HIGH TEMPERATURES WILL CONTINUE INTO
THURSDAY BUT LATEST GUIDANCE SHOWS A RETURN TO WARMER AND SEASONAL
TEMPERATURES NEXT WEEKEND AS THE TROUGH LIFTS OUT OF OUR AREA. /FB
&&
.AVIATION...COLD CORE UPPER LEVEL LOW PRESSURE WILL RESULT IN
SHOWERS TODAY, PRIMARILY ACROSS THE HIGHER TERRAIN, ALONG THE
COAST, AND IN THE UMPQUA BASIN. ISOLATED LIGHTNING WILL ALSO BE
POSSIBLE THIS AFTERNOON AND EVENING, PRIMARILY OVER INTERIOR
PORTIONS OF OREGON.
IFR TO MVFR ALONG THE COAST WILL HAVE SOME HOLES AT TIMES THIS
MORNING, ESPECIALLY AT NORTH BEND. CLOUD DECKS WILL BE MVFR TO VFR
ON THE WEST SIDE TODAY EXCEPT ALONG THE CURRY COAST WHERE IFR TO
MVFR IS EXPECTED. CLOUDS WILL BECOME MORE WIDESPREAD THIS AFTERNOON
AND EVENING. EXPECT VFR BY NOON ALL AREAS EXCEPT AT THE COAST, WHERE
MVFR IS EXPECTED TO STAY IN PLACE. GUSTY WINDS WILL RETURN AGAIN
THIS AFTERNOON AND PERSIST THROUGH MUCH OF THE EVENING. BTL/BPN
&&
.PREV DISCUSSION... /ISSUED 519 AM PDT TUE JUN 18 2013/
DISCUSSION...HAVE MADE VERY FEW CHANGES TO THE GOING FORECAST. A
SIGNIFICANT CHANGE IN THE WEATHER IS IN PROGRESS TODAY AS A DEEP
AND FAIRLY BROAD UPPER LOW OFF THE COAST STARTS MOVING INLAND OVER
THE PACIFIC NORTHWEST. THE ONSHORE SW FLOW ALOFT IS IS BRINGING A
SIGNIFICANT INCREASE IN CLOUDINESS AND INCREASING PRECIPITATION
CHANCES. RADAR IS SHOWING A FEW SHOWERS TRYING TO MATERIALIZE OVER
THE CASCADES AND KLAMATH COUNTY. THE LATEST RAP SHOWS THE SHOWERS
INCREASING OVER THIS SAME AREA AND LIKELY EXPANDING EASTWARD INTO
THE AFTERNOON. ACROSS THE WEST SIDE THE BETTER CHANCES WILL REMAIN
AT THE COAST AND ACROSS THE MOUNTAINS AND AREAS MAINLY WEST AND
NORTH OF MEDFORD. A FEW THUNDERSTORMS MAY ENTER THE MIX THIS
AFTERNOON AND EVENING BUT ANY STORM ACTIVITY WILL LIKELY BE WEAK.
BY WEDNESDAY MORNING THE CENTER OF THE CLOSED UPPER LOW IS
FORECAST TO MOVE INTO WESTERN OREGON ALLOWING SNOW LEVELS TO DIP
TO BETWEEN 5500-6000 FEET. THE CRATER LAKE REGION COULD SEE UP TO
AROUND AN INCH OF SLUSHY ACCUMULATION. THE SYCAN AND SUMMER RIM
AREAS OF SOUTH-CENTRAL OREGON COULD GET IN ON THIS AS WELL. DON`T
EXPECT TO SEE MUCH IN THE WAY OF RAINFALL OVER NORTHERN
CALIFORNIA. HIGH TEMPERATURES WEDNESDAY WILL LIKELY NOT HIT 70 IN
MEDFORD WEDNESDAY WITH UPPER 50S TO LOWER 60S BEING THE RULE OVER
THE EAST. THURSDAY MORNING COULD BRING A BRIEF FREEZE TO AREAS
EAST OF THE CASCADES AND A FREEZE WATCH COULD BE CONSIDERED BY THE
DAY SHIFT TODAY.
THE LOW WILL MOVE OUT SLIGHTLY TO THE NE WITH ABOUT 5-8 DEGREES OF
WARMING AND MAINLY DRY WEATHER THURSDAY. WARMER STILL BY A FEW
DEGREES DAY BY DAY INTO SATURDAY. WE`LL KEEP AN EYE ON THE
NORTHEAST PORTIONS OF THE CWA AS SOME ENERGY MIGHT ROTATE SOUTHWARD
FROM THE LOW WHICH WILL BE SLOW TO MOVE OUT FROM NORTHERN IDAHO.
LATER SATURDAY INTO EARLY NEXT WEEK WE SHOULD SEE AT LEAST THE
COAST REGION UNDER THE GUN AGAIN FOR ANOTHER PERIOD OF LIGHT RAIN
AS PERSISTENT LOW PRESSURE PARKS OFF THE COAST OF BC. STAVISH
AVIATION...
BASED ON THE 18/12Z TAF CYCLE.
COLD CORE UPPER LEVEL LOW PRESSURE WILL RESULT IN SHOWERS TODAY,
PRIMARILY ACROSS THE HIGHER TERRAIN, ALONG THE COAST, AND IN THE
UMPQUA BASIN. ISOLATED LIGHTNING WILL ALSO BE POSSIBLE THIS
AFTERNOON AND EVENING, PRIMARILY OVER INTERIOR PORTIONS OF OREGON.
IFR TO MVFR ALONG THE COAST WILL HAVE SOME HOLES AT TIMES THIS
MORNING, ESPECIALLY AT NORTH BEND. CLOUD DECKS WILL BE MVFR TO VFR
ON THE WEST SIDE TODAY EXCEPT ALONG THE CURRY COAST WHERE IFR TO
MVFR IS EXPECTED. CLOUDS WILL BECOME MORE WIDESPREAD THIS AFTERNOON
AND EVENING. EXPECT VFR BY NOON ALL AREAS EXCEPT AT THE COAST, WHERE
MVFR IS EXPECTED TO STAY IN PLACE. GUSTY WINDS WILL RETURN AGAIN
THIS AFTERNOON AND PERSIST THROUGH MUCH OF THE EVENING. BTL/BPN
&&
.MFR WATCHES/WARNINGS/ADVISORIES...
OR...NONE.
CA...NONE.
PACIFIC COASTAL WATERS...NONE.
$$
FJB/FJB/BTL
AREA FORECAST DISCUSSION
NWS MEDFORD OR
519 AM PDT TUE JUN 18 2013
.DISCUSSION...HAVE MADE VERY FEW CHANGES TO THE GOING FORECAST. A
SIGNIFICANT CHANGE IN THE WEATHER IS IN PROGRESS TODAY AS A DEEP
AND FAIRLY BROAD UPPER LOW OFF THE COAST STARTS MOVING INLAND OVER
THE PACIFIC NORTHWEST. THE ONSHORE SW FLOW ALOFT IS IS BRINGING A
SIGNIFICANT INCREASE IN CLOUDINESS AND INCREASING PRECIPITATION
CHANCES. RADAR IS SHOWING A FEW SHOWERS TRYING TO MATERIALIZE OVER
THE CASCADES AND KLAMATH COUNTY. THE LATEST RAP SHOWS THE SHOWERS
INCREASING OVER THIS SAME AREA AND LIKELY EXPANDING EASTWARD INTO
THE AFTERNOON. ACROSS THE WEST SIDE THE BETTER CHANCES WILL REMAIN
AT THE COAST AND ACROSS THE MOUNTAINS AND AREAS MAINLY WEST AND
NORTH OF MEDFORD. A FEW THUNDERSTORMS MAY ENTER THE MIX THIS
AFTERNOON AND EVENING BUT ANY STORM ACTIVITY WILL LIKELY BE WEAK.
BY WEDNESDAY MORNING THE CENTER OF THE CLOSED UPPER LOW IS
FORECAST TO MOVE INTO WESTERN OREGON ALLOWING SNOW LEVELS TO DIP
TO BETWEEN 5500-6000 FEET. THE CRATER LAKE REGION COULD SEE UP TO
AROUND AN INCH OF SLUSHY ACCUMULATION. THE SYCAN AND SUMMER RIM
AREAS OF SOUTH-CENTRAL OREGON COULD GET IN ON THIS AS WELL. DON`T
EXPECT TO SEE MUCH IN THE WAY OF RAINFALL OVER NORTHERN
CALIFORNIA. HIGH TEMPERATURES WEDNESDAY WILL LIKELY NOT HIT 70 IN
MEDFORD WEDNESDAY WITH UPPER 50S TO LOWER 60S BEING THE RULE OVER
THE EAST. THURSDAY MORNING COULD BRING A BRIEF FREEZE TO AREAS
EAST OF THE CASCADES AND A FREEZE WATCH COULD BE CONSIDERED BY THE
DAY SHIFT TODAY.
THE LOW WILL MOVE OUT SLIGHTLY TO THE NE WITH ABOUT 5-8 DEGREES OF
WARMING AND MAINLY DRY WEATHER THURSDAY. WARMER STILL BY A FEW
DEGREES DAY BY DAY INTO SATURDAY. WE`LL KEEP AN EYE ON THE
NORTHEAST PORTIONS OF THE CWA AS SOME ENERGY MIGHT ROTATE SOUTHWARD
FROM THE LOW WHICH WILL BE SLOW TO MOVE OUT FROM NORTHERN IDAHO.
LATER SATURDAY INTO EARLY NEXT WEEK WE SHOULD SEE AT LEAST THE
COAST REGION UNDER THE GUN AGAIN FOR ANOTHER PERIOD OF LIGHT RAIN
AS PERSISTENT LOW PRESSURE PARKS OFF THE COAST OF BC. STAVISH
&&
.AVIATION...
BASED ON THE 18/12Z TAF CYCLE.
COLD CORE UPPER LEVEL LOW PRESSURE WILL RESULT IN SHOWERS TODAY,
PRIMARILY ACROSS THE HIGHER TERRAIN, ALONG THE COAST, AND IN THE
UMPQUA BASIN. ISOLATED LIGHTNING WILL ALSO BE POSSIBLE THIS
AFTERNOON AND EVENING, PRIMARILY OVER INTERIOR PORTIONS OF OREGON.
IFR TO MVFR ALONG THE COAST WILL HAVE SOME HOLES AT TIMES THIS
MORNING, ESPECIALLY AT NORTH BEND. CLOUD DECKS WILL BE MVFR TO VFR
ON THE WEST SIDE TODAY EXCEPT ALONG THE CURRY COAST WHERE IFR TO
MVFR IS EXPECTED. CLOUDS WILL BECOME MORE WIDESPREAD THIS AFTERNOON
AND EVENING. EXPECT VFR BY NOON ALL AREAS EXCEPT AT THE COAST, WHERE
MVFR IS EXPECTED TO STAY IN PLACE. GUSTY WINDS WILL RETURN AGAIN
THIS AFTERNOON AND PERSIST THROUGH MUCH OF THE EVENING. BTL/BPN
&&
.MFR WATCHES/WARNINGS/ADVISORIES...
OR...NONE.
CA...NONE.
PACIFIC COASTAL WATERS...NONE.
$$
AREA FORECAST DISCUSSION
NWS MEDFORD OR
307 AM PDT TUE JUN 18 2013
.DISCUSSION...HAVE MADE VERY FEW CHANGES TO THE GOING FORECAST. A
SIGNIFICANT CHANGE IN THE WEATHER IS IN PROGRESS TODAY AS A DEEP
AND FAIRLY BROAD UPPER LOW OFF THE COAST STARTS MOVING INLAND OVER
THE PACIFIC NORTHWEST. THE ONSHORE SW FLOW ALOFT IS IS BRINGING A
SIGNIFICANT INCREASE IN CLOUDINESS AND INCREASING PRECIPITATION
CHANCES. RADAR IS SHOWING A FEW SHOWERS TRYING TO MATERIALIZE OVER
THE CASCADES AND KLAMATH COUNTY. THE LATEST RAP SHOWS THE SHOWERS
INCREASING OVER THIS SAME AREA AND LIKELY EXPANDING EASTWARD INTO
THE AFTERNOON. ACROSS THE WEST SIDE THE BETTER CHANCES WILL REMAIN
AT THE COAST AND ACROSS THE MOUNTAINS AND AREAS MAINLY WEST AND
NORTH OF MEDFORD. A FEW THUNDERSTORMS MAY ENTER THE MIX THIS
AFTERNOON AND EVENING BUT ANY STORM ACTIVITY WILL LIKELY BE WEAK.
BY WEDNESDAY MORNING THE CENTER OF THE CLOSED UPPER LOW IS
FORECAST TO MOVE INTO WESTERN OREGON ALLOWING SNOW LEVELS TO DIP
TO BETWEEN 5500-6000 FEET. THE CRATER LAKE REGION COULD SEE UP TO
AROUND AN INCH OF SLUSHY ACCUMULATION. THE SYCAN AND SUMMER RIM
AREAS OF SOUTH-CENTRAL OREGON COULD GET IN ON THIS AS WELL. DON`T
EXPECT TO SEE MUCH IN THE WAY OF RAINFALL OVER NORTHERN
CALIFORNIA. HIGH TEMPERATURES WEDNESDAY WILL LIKELY NOT HIT 70 IN
MEDFORD WEDNESDAY WITH UPPER 50S TO LOWER 60S BEING THE RULE OVER
THE EAST. THURSDAY MORNING COULD BRING A BRIEF FREEZE TO AREAS
EAST OF THE CASCADES AND A FREEZE WATCH COULD BE CONSIDERED BY THE
DAY SHIFT TODAY.
THE LOW WILL MOVE OUT SLIGHTLY TO THE NE WITH ABOUT 5-8 DEGREES OF
WARMING AND MAINLY DRY WEATHER THURSDAY. WARMER STILL BY A FEW
DEGREES DAY BY DAY INTO SATURDAY. WE`LL KEEP AN EYE ON THE
NORTHEAST PORTIONS OF THE CWA AS SOME ENERGY MIGHT ROTATE SOUTHWARD
FROM THE LOW WHICH WILL BE SLOW TO MOVE OUT FROM NORTHERN IDAHO.
LATER SATURDAY INTO EARLY NEXT WEEK WE SHOULD SEE AT LEAST THE
COAST REGION UNDER THE GUN AGAIN FOR ANOTHER PERIOD OF LIGHT RAIN
AS PERSISTENT LOW PRESSURE PARKS OFF THE COAST OF BC. STAVISH
&&
.AVIATION...A WEAK FRONT WILL CONTINUE TO PUSH INLAND THIS
MORNING...BUT WILL RESULT IN LITTLE MORE THAN SCATTERED TO
ISOLATED SHOWERS UNTIL THE UPPER LEVEL TROUGH SWINGS THROUGH THIS
AFTERNOON...RESULTING IN A MUCH BETTER CHANCE FOR PRECIPITATION.
SOME SHOWERS...PARTICULARLY EATS OF INTERSTATE 5...COULD PRODUCE
PERIODS OF THUNDER. EXPECT WIDESPREAD MVFR WITH LOCALIZED IFR AT
THE COAST EARLY THIS MORNING...WITH SOME IMPROVEMENT AFTER
SUNRISE. AREAS OF MVFR WILL PUSH INLAND FROM THE COAST ALONG WITH
PRECIPITATION TODAY...MOSTLY INTO THE UMPQUA BASIN AND THE
CASCADES...WHILE VFR SHOULD PREVAIL SOUTH OF THE UMPQUA DIVIDE AND
ACROSS THE EAST SIDE. GUSTY WINDS WILL RETURN AGAIN THIS AFTERNOON
AND PERSIST UNTIL JUST AFTER SUNSET. -BPN
&&
.MFR WATCHES/WARNINGS/ADVISORIES...
OR...NONE.
CA...NONE.
PACIFIC COASTAL WATERS...NONE.
$$
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
358 PM EDT TUE JUN 18 2013
.SYNOPSIS...
THE PERSISTENT JUNE PATTERN OF A BROAD THROUGH OVER THE MID-
ATLANTIC AND NORTHEAST STATES IS FORECAST TO TRANSITION AND BE
REPLACED BY A SUMMERTIME UPPER LEVEL RIDGE MIGRATING EASTWARD FROM
THE PLAINS. A SLIGHTLY COOLER AND LESS HUMID AIR MASS WILL FOLLOW
IN THE WAKE OF A COLD FRONT TONIGHT INTO THURSDAY. INCREASING HEAT
AND HUMIDITY WILL ARRIVE ON SCHEDULE WITH THE OFFICIAL START OF
ASTRONOMICAL SUMMER...AND LAST INTO THE UPCOMING WEEKEND.
&&
.NEAR TERM /UNTIL 6 AM WEDNESDAY MORNING/...
BEST LLVL CONVERGENCE IS ALONG THE TURNPIKE AND SRN BORDER.
THUS...EXPECT HIGHEST CHCS FOR SHRA TO BE THERE EARLY THIS
EVENING. A FEW MORE CU ARE BUILDING OVER THE LOCAL AREA...WHERE
HEATING HAS THUS FAR BEEN HAMPERED BY THICK HIGH CLOUD COVER.
SO...CANNOT PULL ALL MENTIONS OF SHOWERS - ESP WITH THE RUC
INSISTING ON MAKING MORE/HEAVY SHOWERS OVER THE RIDGE AND
VALLEY/MID SUSQ BEFORE SUNSET. TALL CU OVER BFD WILL ALSO WARRANT
AT LEAST ISOLD POPS IN THE NRN HILLS FOR THE NEXT FEW HOURS AS
WELL. SUBSIDENCE AND CLEARING WILL COME TO THE AREA FROM N-S
THROUGH THE LATE EVENING AND OVERNIGHT. WINDS DO GO CALM IN MANY
LOCATIONS. SO A LITTLE FOG IS POSSIBLE - EARLY IN BFD BEFORE
DEWPOINTS TANK...AND AROUND THE REST OF THE AREA LATER AT
NIGHT...ESP THOSE PLACES THAT DID GET WET TODAY.
&&
.SHORT TERM /6 AM WEDNESDAY MORNING THROUGH 6 PM WEDNESDAY/...
LAST SHORTWAVE TO ENHANCE THE TROUGH OVERHEAD WILL RUN OVER THE
REGION AROUND SUNRISE...AND THEN THE HEIGHTS START TO RISE
STEADILY. SFC HIGH PRESSURE FINALLY PUSHES FAR ENOUGH TO THE SOUTH
AND INTO PA TO REMOVE MOST CLOUD COVER AND ALMOST EVERY BIT OF
POPS. WILL JUST HANG ONTO A SLIGHT CHC OVER THE HIGHEST TERRAIN OF
THE LAURELS/SC MTS WHERE ENOUGH MSTR AND ELEVATED HEATING SURFACES
MAY COMBINE TO POP OFF A SHRA OR TWO. TEMPS WILL BE A DEG OR TWO
LOWER WED THAN TUES.
&&
.LONG TERM /WEDNESDAY NIGHT THROUGH TUESDAY/...
UPPER RIDGE OVER CENTRAL PLAINS WILL BUILD EASTWARD INTO PA WED
NIGHT THROUGH SATURDAY...AS 500 MB HEIGHTS RISE TO 588DM. CENTER
OF SURFACE HIGH SLIPS SE ACROSS GREAT LAKES AND IS LOCATED OVER
CENTRAL PA ON WED NIGHT...SETTING UP IDEAL RADIATIONAL COOLING
CONDITIONS. DEWPOINTS WILL STILL BE LINGERING IN THE 50S ACROSS
SOUTHERN PA...BUT MUCH LOWER DEWPOINTS NORTH OF I-80 WILL ALLOW
TEMPS TO DROP WELL INTO THE 40S.
STARTING THU...LLVL S-SWLY RETURN FLOW AROUND SFC HIGH /DRIFTING
OFF THE EAST COAST/ WILL BRING A GRADUAL INCREASE IN LLVL MSTR
THRU THE END OF THE WORK WEEK...WITH JUST A SLGT CHC FOR AN AFTN
POP-UP/AIRMASS TYPE TSTM ON FRI. OTHERWISE...SUNNY TO MOSTLY SUNNY
CONDITIONS WILL PREVAIL AS TEMPS CLIMB TO SEASONAL NORMALS ON THU
AND BEGIN A STRING OF ABOVE NORMAL DAYS ON FRIDAY.
HEAT AND HUMIDITY CONTINUE TO INCREASE HEADING INTO THE WEEKEND AS
HEIGHTS PEAK. BIGGER SURGE OF HIGHER DEWPOINTS SLIDES IN FROM THE
WEST AS HEAT CONTINUES TO BUILD...SO A SERIES OF VERY WARM AND
HUMID DAYS ARE IN STORE FOR SAT INTO TUES...WITH OVERNIGHT LOWS
REMAINING QUITE MILD AS WELL. WITH STAGNANT AIR AND INCREASING
HUMIDITY ON BACK SIDE OF SURFACE HIGH...HELD ON TO 20-30 POPS MOST
AFTERNOONS - WITH HIGHEST CHANCES OVER WESTERN HIGHER TERRAIN OF
ISOLATED DIFFERENTIAL HEATING INITIATED STORMS.
PATTERN ALSO HAS A RING-OF-FIRE LOOK TO IT SO WILL NEED TO WATCH
FOR MCS ACTIVITY/RIDGE ROLLERS SLIDING DOWN FROM THE NW...THOUGH
LATEST MODELS NOT QUITE AS BULLISH ON THAT. EC OVERALL PRODUCING
MORE CONVECTION THAN THE GFS...BUT GENERAL AREAS ARE SIMILAR.
&&
.AVIATION /20Z TUESDAY THROUGH SUNDAY/...
SCT SHRA ALONG THE SRN BORDER MAY BE JOINED BY ISOLD/SCT SHRA OVER
THE BULK OF THE AREA LATE THIS AFTN. BUT FOCUSING MECHANISMS ARE
ILL-DEFINED AT THIS TIME. RECENT RUC RUNS CONTINUE TO DEVELOP SHRA
OVER THE CENTRAL COS...AND TALL CU PRESENT OVER BFD. WILL KEEP
VCSH IN MOST AIRFIELDS THROUGH 22-00Z. SRN TERMINALS MAY STILL
HAVE SOME SHRA NEARBY THROUGH MIDNIGHT...BUT COVG WILL REMAIN
SPARSE ENOUGH TO NOT MENTION THE IN TAFS.
MVFR CIGS AND VSBYS WILL AGAIN BE A POSSIBILITY TONIGHT IN FOG -
ESP WHERE RAIN OCCURS. SO SOME MENTIONS OF FOG WILL BE IN THE
TAFS. HIGH PRESSURE THEN CONTROLS THE WX INTO THE WEEKEND. JUST A
VERY SLIGHT CHC OF A SHRA EXISTS OVER THE HIGHEST TERRAIN ON WED.
BUT 99PCT OF THE AREA WILL BE DRY AND VFR.
OUTLOOK...
THU-FRI...NO SIG WX EXPECTED.
SAT-SUN...ISOLD PM TSRA IMPACTS POSSIBLE.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...STEINBUGL
NEAR TERM...DANGELO
SHORT TERM...DANGELO
LONG TERM...RXR
AVIATION...DANGELO
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
302 PM EDT TUE JUN 18 2013
.SYNOPSIS...
THE PERSISTENT JUNE PATTERN OF A BROAD THROUGH OVER THE MID-
ATLANTIC AND NORTHEAST STATES IS FORECAST TO TRANSITION AND BE
REPLACED BY A SUMMERTIME UPPER LEVEL RIDGE MIGRATING EASTWARD FROM
THE PLAINS. A SLIGHTLY COOLER AND LESS HUMID AIR MASS WILL FOLLOW
IN THE WAKE OF A COLD FRONT TONIGHT INTO THURSDAY. INCREASING HEAT
AND HUMIDITY WILL ARRIVE ON SCHEDULE WITH THE OFFICIAL START OF
ASTRONOMICAL SUMMER...AND LAST INTO THE UPCOMING WEEKEND.
&&
.NEAR TERM /UNTIL 6 AM WEDNESDAY MORNING/...
BEST LLVL CONVERGENCE IS ALONG THE TURNPIKE AND SRN BORDER.
THUS...EXPECT HIGHEST CHCS FOR SHRA TO BE THERE EARLY THIS
EVENING. A FEW MORE CU ARE BUILDING OVER THE LOCAL AREA...WHERE
HEATING HAS THUS FAR BEEN HAMPERED BY THICK HIGH CLOUD COVER.
SO...CANNOT PULL ALL MENTIONS OF SHOWERS - ESP WITH THE RUC
INSISTING ON MAKING MORE/HEAVY SHOWERS OVER THE RIDGE AND
VALLEY/MID SUSQ BEFORE SUNSET. TALL CU OVER BFD WILL ALSO WARRANT
AT LEAST ISOLD POPS IN THE NRN HILLS FOR THE NEXT FEW HOURS AS
WELL. SUBSIDENCE AND CLEARING WILL COME TO THE AREA FROM N-S
THROUGH THE LATE EVENING AND OVERNIGHT. WINDS DO GO CALM IN MANY
LOCATIONS. SO A LITTLE FOG IS POSSIBLE - EARLY IN BFD BEFORE
DEWPOINTS TANK...AND AROUND THE REST OF THE AREA LATER AT
NIGHT...ESP THOSE PLACES THAT DID GET WET TODAY.
&&
.SHORT TERM /6 AM WEDNESDAY MORNING THROUGH 6 PM WEDNESDAY/...
LAST SHORTWAVE TO ENHANCE THE TROUGH OVERHEAD WILL RUN OVER THE
REGION AROUND SUNRISE...AND THEN THE HEIGHTS START TO RISE
STEADILY. SFC HIGH PRESSURE FINALLY PUSHES FAR ENOUGH TO THE SOUTH
AND INTO PA TO REMOVE MOST CLOUD COVER AND ALMOST EVERY BIT OF
POPS. WILL JUST HANG ONTO A SLIGHT CHC OVER THE HIGHEST TERRAIN OF
THE LAURELS/SC MTS WHERE ENOUGH MSTR AND ELEVATED HEATING SURFACES
MAY COMBINE TO POP OFF A SHRA OR TWO. TEMPS WILL BE A DEG OR TWO
LOWER WED THAN TUES.
&&
.LONG TERM /WEDNESDAY NIGHT THROUGH TUESDAY/...
A DEEP CLOSED LOW MOVG ACRS THE PACIFIC NW AND NRN ROCKIES WILL
ALLOW THE CENTRAL PLAINS UPPER RIDGE TO SLIDE EWD WITH RISING HGTS
EXPECTED DOWNSTREAM OVER THE ERN CONUS. CONSENSUS OF MODEL AND
ENSEMBLE DATA CONTINUES TO BUILD THE RIDGE TO 588+DM THRU THE
WEEKEND WITH THE FIRST TASTE OF SUMMERTIME HEAT/HUMIDITY ARRIVING
ON SCHEDULE.
LLVL S-SWLY RETURN FLOW AROUND SFC HIGH PRES DRIFTING OFF THE EAST
COAST WILL BRING AN INCREASE IN LLVL MSTR THRU THE END OF THE WORK
WEEK...WITH JUST A SLGT CHC FOR AN AFTN POP-UP/AIRMASS TYPE SHOWER
OR TSTM ON FRI.
ABOVE NORMAL 500 HPA HEIGHTS OVERSPREAD THE COMMONWEALTH THIS
WEEKEND. THIS SHOULD TRANSLATE INTO WARMER-THAN-NORMAL TEMPS WITH
THE GFS-BASED MOS GUID MORE BULLISH THAN THE EC MOS ON THE HEAT.
PATTERN ALSO HAS A RING-OF-FIRE LOOK TO IT SO WILL NEED TO WATCH
FOR MCS ACTIVITY/RIDGE ROLLERS.
&&
.AVIATION /19Z TUESDAY THROUGH SUNDAY/...
SCT SHRA ALONG THE SRN BORDER MAY BE JOINED BY ISOLD/SCT SHRA OVER
THE BULK OF THE AREA LATE THIS AFTN. BUT FOCUSING MECHANISMS ARE
ILL-DEFINED AT THIS TIME. RECENT RUC RUNS CONTINUE TO DEVELOP SHRA
OVER THE CENTRAL COS...AND TALL CU PRESENT OVER BFD. WILL KEEP
VCSH IN MOST AIRFIELDS THROUGH 22-00Z. SRN TERMINALS MAY STILL
HAVE SOME SHRA NEARBY THROUGH MIDNIGHT...BUT COVG WILL REMAIN
SPARSE ENOUGH TO NOT MENTION THE IN TAFS.
MVFR CIGS AND VSBYS WILL AGAIN BE A POSSIBILITY TONIGHT IN FOG -
ESP WHERE RAIN OCCURS. SO SOME MENTIONS OF FOG WILL BE IN THE
TAFS. HIGH PRESSURE THEN CONTROLS THE WX INTO THE WEEKEND. JUST A
VERY SLIGHT CHC OF A SHRA EXISTS OVER THE HIGHEST TERRAIN ON WED.
BUT 99PCT OF THE AREA WILL BE DRY AND VFR.
OUTLOOK...
THU-FRI...NO SIG WX EXPECTED.
SAT-SUN...ISOLD PM TSRA IMPACTS POSSIBLE.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...STEINBUGL
NEAR TERM...DANGELO
SHORT TERM...DANGELO
LONG TERM...STEINBUGL
AVIATION...DANGELO
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
1048 AM EDT TUE JUN 18 2013
.SYNOPSIS...
THE PERSISTENT JUNE PATTERN OF BROAD TROUGHING OVER THE MID-
ATLANTIC AND NORTHEAST STATES IS FORECAST TO TRANSITION AND BE
REPLACED BY A SUMMERTIME UPPER LEVEL RIDGE MIGRATING EASTWARD
FROM THE PLAINS. A SLIGHTLY COOLER AND LESS HUMID AIRMASS WILL
FOLLOW IN THE WAKE OF A COLD FRONT TONIGHT INTO THURSDAY.
INCREASING HEAT AND HUMIDITY WILL ARRIVE ON SCHEDULE WITH THE
OFFICIAL START OF ASTRONOMICAL SUMMER...AND LAST INTO THE
UPCOMING WEEKEND.
&&
.NEAR TERM /THROUGH TONIGHT/...
SHOWERS WITH EMBEDDED THUNDER ROLLING IN FROM THE S. STUFF OVER
PBZ AREA JUST REFUSES TO GET INTO THE LAURELS. SO ALL IS ON
TRACK...AND NO SIG CHANGES HAVE BEEN MADE AT 1030AM.
PREV DISC...
JUST A FEW MINOR TWEAKS TO SKY AND POPS BASED ON CURRENT RADAR AND
SATELLITE TRENDS. MOST OF THE TSRA WILL BE THIS AFTN AS HEATING
KICKS IN EVEN THOUGH A FEW BLIPS ARE ON THE SCOPE ALREADY. BUT
MULTIPLE FORCING MECHANISMS AND SFC BOUNDARIES WILL MAKE IT PRETTY
MUCH IMPOSSIBLE TO PINPOINT WHERE/WHEN SHOWERS WILL BE TODAY.
PREV DISC...
BELT OF STRONGER MID-LVL FLOW ON THE SRN EDGE OF SHORTWAVE TROUGH
MOVG EWD FROM QUEBEC TO THE MARITIMES WILL SHIFT EWD ACRS NEW
ENGLAND THIS MORNING. AN ATTENDANT SFC COLD FRONT DRAPED ALONG THE
LWR LKS IS TEAMING WITH A WELL-DEFINED 300MB JET ENTRANCE REGION
TO MAINTAIN A CLUSTER SHOWERS/TSTMS OVER NW PA...WITH A FEW LONE
CELLS CROSSING LK ERIE. THE LATEST MESO MODELS CONTINUE TO WEAKEN
THIS AREA OF PCPN AS IT SHIFTS EWD ACRS MCKEAN CO THRU 12Z. OUTSIDE
OF THE NW MTNS...MOST AREAS SHOULD REMAIN DRY THRU DAYBREAK.
IR SATL LOOP SHOWS A SHIELD OF LYRD MID-HIGH CLOUDS SPREADING NEWD
ACRS CNTRL PA. THESE CLOUDS ARE ASSOCD WITH A SHORTWAVE LIFTING
THRU THE TN VLY AND WEAK SFC LOW ADVANCING EWD TOWARD THE CNTRL
MID-ATLC COAST. ANOTHER COMPACT SHORTWAVE IS CURRENTLY ROTATING
ACRS MN..AND WILL TRACK SEWD INTO THE LWR-MID OH VLY BY THIS
AFTN. THE APPROACHING SHORTWAVE ENERGY /FROM THE SW/ AND
AFOREMENTIONED SFC COLD FRONT /FROM THE NW/ SHOULD PROVIDE
SUFFICIENT FORCING/LIFT TO FUEL SCT TO NMRS TSTM DEVELOPMENT INTO
THE AFTN. HOWEVER THERE IS SOME QUESTION AS TO WHERE THE BEST
LOCATION/AERIAL CVRG WILL BE. THE LATEST HRRR AND 00Z SPC WRF/SSEO
HIGHLIGHT THE AREA SOUTH OF I-80...WITH THE HRRR SHOWING A NOTABLE
INCREASE IN CONVECTION AROUND THE 17-18Z TIMEFRAME.
THE SVR THREAT APPEARS MARGINAL DUE TO WEAK/MODEST INSTABILITY.
HOWEVER I CANT RULE OUT A FEW ORGANIZED STORMS GIVEN 35-40 KT OF
EFFECTIVE BULK SHEAR. COULD ALSO SEE SOME LOCALLY HEAVY RAINS
WITH THE MAIN SURGE OF ANOMALOUS PWATS OVER SOUTHEAST PA. THE
LATER ARRIVING MESO GUIDANCE SEEMS TO BE FORMING A CONSENSUS THAT
THE SRN 1/2 OF THE CWA SHOULD SEE THE MOST ACTIVITY COINCIDENT
WITH PEAK HEATING. AS SUCH...EXPECT TSTM CVRG TO WANE/TAPER OFF
WITH THE ONSET OF NIGHTFALL/SWD MVMT OF COLD FRONT.
THE FRONT WILL PUSH SOUTH ACRS THE CWA BY LATER TONIGHT WITH MUCH
DRIER/BELOW NORMAL PWAT AIR ARRIVING FROM THE NORTH. WILL HOLD
ONTO SOME LOW POPS ALONG THE MASON DIXON LINE INTO EARLY WEDNESDAY
MORNING BUT MOST AREAS SHOULD BE DRY AFT 06Z...ESPECIALLY TO THE
NORTH OF THE TURNPIKE.
&&
.SHORT TERM /WEDNESDAY THROUGH WEDNESDAY NIGHT/...
HIGH PRES WILL PREVAIL ON WEDNESDAY BRINGING PLENTY OF SUNSHINE.
THE WEATHER SHOULD BE RATHER COMFORTABLE AND PLEASANT WITH
COOLER NLY WINDS AND LOW HUMIDITY...WITH TEMPS GENERALLY IN THE
70S. CLR/CALM CONDS WED NIGHT SHOULD ALLOW OVERNIGHT LOWS TO FALL
INTO THE LOW-MID 40S ACRS THE NRN TIER...AND LOW-MID 50S IN THE
SOUTH. SOME OF THE USUAL COLD SPOTS IN THE NRN MTNS COULD DIP
INTO THE UPPER 30S.
&&
.LONG TERM /THURSDAY THROUGH MONDAY/...
A DEEP CLOSED LOW MOVG ACRS THE PACIFIC NW AND NRN ROCKIES WILL
ALLOW THE CENTRAL PLAINS UPPER RIDGE TO SLIDE EWD WITH RISING HGTS
EXPECTED DOWNSTREAM OVER THE ERN CONUS. CONSENSUS OF MODEL AND
ENSEMBLE DATA CONTINUES TO BUILD THE RIDGE TO 588+DM THRU THE
WEEKEND WITH THE FIRST TASTE OF SUMMERTIME HEAT/HUMIDITY ARRIVING
ON SCHEDULE.
LLVL S-SWLY RETURN FLOW AROUND SFC HIGH PRES DRIFTING OFF THE EAST
COAST WILL BRING AN INCREASE IN LLVL MSTR THRU THE END OF THE WORK
WEEK...WITH JUST A SLGT CHC FOR AN AFTN POP-UP/AIRMASS TYPE SHOWER
OR TSTM ON FRI.
ABOVE NORMAL 500 HPA HEIGHTS OVERSPREAD THE COMMONWEALTH THIS
WEEKEND. THIS SHOULD TRANSLATE INTO WARMER-THAN-NORMAL TEMPS WITH
THE GFS-BASED MOS GUID MORE BULLISH THAN THE EC MOS ON THE HEAT.
PATTERN ALSO HAS A RING-OF-FIRE LOOK TO IT SO WILL NEED TO WATCH
FOR MCS ACTIVITY/RIDGE ROLLERS.
&&
.AVIATION /15Z TUESDAY THROUGH SATURDAY/...
LOW LEVEL MOISTURE MUCH HIGHER IN THE S THAN ELSEWHERE. WAVE
ROLLING TO THE EAST OVER THE CENTRAL APPALACHIANS IS PUSHING A
SHIELD OF RAIN WITH EMBEDDED THUNDER INTO THE LOWER SUSQ WHICH
WILL NEGATIVELY IMPACT FLYING CONDITIONS AT THV/MDT/CXY/LNS BEFORE
NOON. A BOUNDARY OVER THE NRN TIER THIS MORNING WILL INCH TO THE
SOUTH AND DEVELOP SCATTERED SHRA/TSRA THIS AFTN OVER THE CENTRAL
AND SWRN AIRFIELDS AS WELL. BFD LOOKS TO BE THE TERMINAL WITH THE
LEAST CHC FOR SHRA/TSRA. VFR CONDS WILL PREDOMINATE...WITH BRIEF
VSBY REDUCTION POSSIBLE WITH ANY SHRA/TSRA. CURRENT THINKING IS
THAT THE FRONT DOES NOT CLEAR THE SOUTHERN TIER UNTIL LATER THIS
EVENING. BUT WITHOUT DIURNAL HEAT...MUCH OF THE TSRA WILL BE DONE
AROUND 02Z. IFR CIGS AND VSBYS WILL AGAIN BE A POSSIBILITY
TONIGHT IN FOG - ESP WHERE RAIN OCCURS THIS AFTN.
OUTLOOK...
WED...EARLY AM LGT RAIN/LOW CIGS POSSIBLE JST/AOO.
THU...NO SIG WX EXPECTED.
FRI-SAT...ISOLD PM TSRA IMPACTS POSSIBLE.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...STEINBUGL
NEAR TERM...DANGELO/STEINBUGL
SHORT TERM...STEINBUGL
LONG TERM...STEINBUGL
AVIATION...DANGELO/CERU
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
812 AM EDT TUE JUN 18 2013
.SYNOPSIS...
THE PERSISTENT JUNE PATTERN OF BROAD TROUGHING OVER THE MID-
ATLANTIC AND NORTHEAST STATES IS FORECAST TO TRANSITION AND BE
REPLACED BY A SUMMERTIME UPPER LEVEL RIDGE MIGRATING EASTWARD
FROM THE PLAINS. A SLIGHTLY COOLER AND LESS HUMID AIRMASS WILL
FOLLOW IN THE WAKE OF A COLD FRONT TONIGHT INTO THURSDAY.
INCREASING HEAT AND HUMIDITY WILL ARRIVE ON SCHEDULE WITH THE
OFFICIAL START OF ASTRONOMICAL SUMMER...AND LAST INTO THE
UPCOMING WEEKEND.
&&
.NEAR TERM /THROUGH TONIGHT/...
JUST A FEW MINOR TWEAKS TO SKY AND POPS BASED ON CURRENT RADAR AND
SATELLITE TRENDS. MOST OF THE TSRA WILL BE THIS AFTN AS HEATING
KICKS IN EVEN THOUGH A FEW BLIPS ARE ON THE SCOPE ALREADY. BUT
MULTIPLE FORCING MECHANISMS AND SFC BOUNDARIES WILL MAKE IT PRETTY
MUCH IMPOSSIBLE TO PINPOINT WHERE/WHEN SHOWERS WILL BE TODAY.
PREV DISC...
BELT OF STRONGER MID-LVL FLOW ON THE SRN EDGE OF SHORTWAVE TROUGH
MOVG EWD FROM QUEBEC TO THE MARITIMES WILL SHIFT EWD ACRS NEW
ENGLAND THIS MORNING. AN ATTENDANT SFC COLD FRONT DRAPED ALONG THE
LWR LKS IS TEAMING WITH A WELL-DEFINED 300MB JET ENTRANCE REGION
TO MAINTAIN A CLUSTER SHOWERS/TSTMS OVER NW PA...WITH A FEW LONE
CELLS CROSSING LK ERIE. THE LATEST MESO MODELS CONTINUE TO WEAKEN
THIS AREA OF PCPN AS IT SHIFTS EWD ACRS MCKEAN CO THRU 12Z. OUTSIDE
OF THE NW MTNS...MOST AREAS SHOULD REMAIN DRY THRU DAYBREAK.
IR SATL LOOP SHOWS A SHIELD OF LYRD MID-HIGH CLOUDS SPREADING NEWD
ACRS CNTRL PA. THESE CLOUDS ARE ASSOCD WITH A SHORTWAVE LIFTING
THRU THE TN VLY AND WEAK SFC LOW ADVANCING EWD TOWARD THE CNTRL
MID-ATLC COAST. ANOTHER COMPACT SHORTWAVE IS CURRENTLY ROTATING
ACRS MN..AND WILL TRACK SEWD INTO THE LWR-MID OH VLY BY THIS
AFTN. THE APPROACHING SHORTWAVE ENERGY /FROM THE SW/ AND
AFOREMENTIONED SFC COLD FRONT /FROM THE NW/ SHOULD PROVIDE
SUFFICIENT FORCING/LIFT TO FUEL SCT TO NMRS TSTM DEVELOPMENT INTO
THE AFTN. HOWEVER THERE IS SOME QUESTION AS TO WHERE THE BEST
LOCATION/AERIAL CVRG WILL BE. THE LATEST HRRR AND 00Z SPC WRF/SSEO
HIGHLIGHT THE AREA SOUTH OF I-80...WITH THE HRRR SHOWING A NOTABLE
INCREASE IN CONVECTION AROUND THE 17-18Z TIMEFRAME.
THE SVR THREAT APPEARS MARGINAL DUE TO WEAK/MODEST INSTABILITY.
HOWEVER I CANT RULE OUT A FEW ORGANIZED STORMS GIVEN 35-40 KT OF
EFFECTIVE BULK SHEAR. COULD ALSO SEE SOME LOCALLY HEAVY RAINS
WITH THE MAIN SURGE OF ANOMALOUS PWATS OVER SOUTHEAST PA. THE
LATER ARRIVING MESO GUIDANCE SEEMS TO BE FORMING A CONSENSUS THAT
THE SRN 1/2 OF THE CWA SHOULD SEE THE MOST ACTIVITY COINCIDENT
WITH PEAK HEATING. AS SUCH...EXPECT TSTM CVRG TO WANE/TAPER OFF
WITH THE ONSET OF NIGHTFALL/SWD MVMT OF COLD FRONT.
THE FRONT WILL PUSH SOUTH ACRS THE CWA BY LATER TONIGHT WITH MUCH
DRIER/BELOW NORMAL PWAT AIR ARRIVING FROM THE NORTH. WILL HOLD
ONTO SOME LOW POPS ALONG THE MASON DIXON LINE INTO EARLY WEDNESDAY
MORNING BUT MOST AREAS SHOULD BE DRY AFT 06Z...ESPECIALLY TO THE
NORTH OF THE TURNPIKE.
&&
.SHORT TERM /WEDNESDAY THROUGH WEDNESDAY NIGHT/...
HIGH PRES WILL PREVAIL ON WEDNESDAY BRINGING PLENTY OF SUNSHINE.
THE WEATHER SHOULD BE RATHER COMFORTABLE AND PLEASANT WITH
COOLER NLY WINDS AND LOW HUMIDITY...WITH TEMPS GENERALLY IN THE
70S. CLR/CALM CONDS WED NIGHT SHOULD ALLOW OVERNIGHT LOWS TO FALL
INTO THE LOW-MID 40S ACRS THE NRN TIER...AND LOW-MID 50S IN THE
SOUTH. SOME OF THE USUAL COLD SPOTS IN THE NRN MTNS COULD DIP
INTO THE UPPER 30S.
&&
.LONG TERM /THURSDAY THROUGH MONDAY/...
A DEEP CLOSED LOW MOVG ACRS THE PACIFIC NW AND NRN ROCKIES WILL
ALLOW THE CENTRAL PLAINS UPPER RIDGE TO SLIDE EWD WITH RISING HGTS
EXPECTED DOWNSTREAM OVER THE ERN CONUS. CONSENSUS OF MODEL AND
ENSEMBLE DATA CONTINUES TO BUILD THE RIDGE TO 588+DM THRU THE
WEEKEND WITH THE FIRST TASTE OF SUMMERTIME HEAT/HUMIDITY ARRIVING
ON SCHEDULE.
LLVL S-SWLY RETURN FLOW AROUND SFC HIGH PRES DRIFTING OFF THE EAST
COAST WILL BRING AN INCREASE IN LLVL MSTR THRU THE END OF THE WORK
WEEK...WITH JUST A SLGT CHC FOR AN AFTN POP-UP/AIRMASS TYPE SHOWER
OR TSTM ON FRI.
ABOVE NORMAL 500 HPA HEIGHTS OVERSPREAD THE COMMONWEALTH THIS
WEEKEND. THIS SHOULD TRANSLATE INTO WARMER-THAN-NORMAL TEMPS WITH
THE GFS-BASED MOS GUID MORE BULLISH THAN THE EC MOS ON THE HEAT.
PATTERN ALSO HAS A RING-OF-FIRE LOOK TO IT SO WILL NEED TO WATCH
FOR MCS ACTIVITY/RIDGE ROLLERS.
&&
.AVIATION /12Z TUESDAY THROUGH SATURDAY/...
QUASI STATIONARY BOUNDARY IS CURRENTLY MEADERING IN THE NW CORNER
OF THE STATE. WEAK SHOWERS ARE MAKING THERE WAY ACROSS THE
NORTHERN HALF OF THE STATE. ANY SHOWERS ARE NOT REDUCING
CONDITIONS. LOW LEVEL MOISTURE HAS CREPT UP INTO THE SOUTHEASTERN
CORNER OF THE STATE. IFR VSBYS AT LNS SHOULD CONTINUE FOR THE NEXT
FEW HOURS BUT SHOULD LIFT BY 15Z AT THE LATEST. AS THE BOUNDARY
MOVES TO THE SOUTH SCATTERED SHRA/TSRA SHOULD DEVELOP THIS AFTN.
VFR CONDS WILL PREDOMINATE...WITH BRIEF VSBY REDUCTION POSSIBLE
WITH ANY SHRA/TSRA. CURRENT MODELS SHOW ANY PRECIPITATION COULD
LINGER ALONG THE MASON DIXON LINE...AND AT LNS...MDT AND JST
THROUGH 06Z WEDNESDAY. IFR CIGS AND VSBYS WILL AGAIN BE A
POSSIBILITY TONIGHT.
OUTLOOK...
WED...EARLY AM LGT RAIN/LOW CIGS POSSIBLE JST/AOO.
THU...NO SIG WX EXPECTED.
FRI-SAT...ISOLD PM TSRA IMPACTS POSSIBLE.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...STEINBUGL
NEAR TERM...DANGELO/STEINBUGL
SHORT TERM...STEINBUGL
LONG TERM...STEINBUGL
AVIATION...FITZGERALD/CERU
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
701 AM EDT TUE JUN 18 2013
.SYNOPSIS...
THE PERSISTENT JUNE PATTERN OF BROAD TROUGHING OVER THE MID-
ATLANTIC AND NORTHEAST STATES IS FORECAST TO TRANSITION AND BE
REPLACED BY A SUMMERTIME UPPER LEVEL RIDGE MIGRATING EASTWARD
FROM THE PLAINS. A SLIGHTLY COOLER AND LESS HUMID AIRMASS WILL
FOLLOW IN THE WAKE OF A COLD FRONT TONIGHT INTO THURSDAY.
INCREASING HEAT AND HUMIDITY WILL ARRIVE ON SCHEDULE WITH THE
OFFICIAL START OF ASTRONOMICAL SUMMER...AND LAST INTO THE
UPCOMING WEEKEND.
&&
.NEAR TERM /THROUGH TONIGHT/...
BELT OF STRONGER MID-LVL FLOW ON THE SRN EDGE OF SHORTWAVE TROUGH
MOVG EWD FROM QUEBEC TO THE MARITIMES WILL SHIFT EWD ACRS NEW
ENGLAND THIS MORNING. AN ATTENDANT SFC COLD FRONT DRAPED ALONG THE
LWR LKS IS TEAMING WITH A WELL-DEFINED 300MB JET ENTRANCE REGION
TO MAINTAIN A CLUSTER SHOWERS/TSTMS OVER NW PA...WITH A FEW LONE
CELLS CROSSING LK ERIE. THE LATEST MESO MODELS CONTINUE TO WEAKEN
THIS AREA OF PCPN AS IT SHIFTS EWD ACRS MCKEAN CO THRU 12Z. OUTSIDE
OF THE NW MTNS...MOST AREAS SHOULD REMAIN DRY THRU DAYBREAK.
IR SATL LOOP SHOWS A SHIELD OF LYRD MID-HIGH CLOUDS SPREADING NEWD
ACRS CNTRL PA. THESE CLOUDS ARE ASSOCD WITH A SHORTWAVE LIFTING
THRU THE TN VLY AND WEAK SFC LOW ADVANCING EWD TOWARD THE CNTRL
MID-ATLC COAST. ANOTHER COMPACT SHORTWAVE IS CURRENTLY ROTATING
ACRS MN..AND WILL TRACK SEWD INTO THE LWR-MID OH VLY BY THIS
AFTN. THE APPROACHING SHORTWAVE ENERGY /FROM THE SW/ AND
AFOREMENTIONED SFC COLD FRONT /FROM THE NW/ SHOULD PROVIDE
SUFFICIENT FORCING/LIFT TO FUEL SCT TO NMRS TSTM DEVELOPMENT INTO
THE AFTN. HOWEVER THERE IS SOME QUESTION AS TO WHERE THE BEST
LOCATION/AERIAL CVRG WILL BE. THE LATEST HRRR AND 00Z SPC WRF/SSEO
HIGHLIGHT THE AREA SOUTH OF I-80...WITH THE HRRR SHOWING A NOTABLE
INCREASE IN CONVECTION AROUND THE 17-18Z TIMEFRAME.
THE SVR THREAT APPEARS MARGINAL DUE TO WEAK/MODEST INSTABILITY.
HOWEVER I CANT RULE OUT A FEW ORGANIZED STORMS GIVEN 35-40 KT OF
EFFECTIVE BULK SHEAR. COULD ALSO SEE SOME LOCALLY HEAVY RAINS
WITH THE MAIN SURGE OF ANOMALOUS PWATS OVER SOUTHEAST PA. THE
LATER ARRIVING MESO GUIDANCE SEEMS TO BE FORMING A CONSENSUS THAT
THE SRN 1/2 OF THE CWA SHOULD SEE THE MOST ACTIVITY COINCIDENT
WITH PEAK HEATING. AS SUCH...EXPECT TSTM CVRG TO WANE/TAPER OFF
WITH THE ONSET OF NIGHTFALL/SWD MVMT OF COLD FRONT.
THE FRONT WILL PUSH SOUTH ACRS THE CWA BY LATER TONIGHT WITH MUCH
DRIER/BELOW NORMAL PWAT AIR ARRIVING FROM THE NORTH. WILL HOLD
ONTO SOME LOW POPS ALONG THE MASON DIXON LINE INTO EARLY WEDNESDAY
MORNING BUT MOST AREAS SHOULD BE DRY AFT 06Z...ESPECIALLY TO THE
NORTH OF THE TURNPIKE.
&&
.SHORT TERM /WEDNESDAY THROUGH WEDNESDAY NIGHT/...
HIGH PRES WILL PREVAIL ON WEDNESDAY BRINGING PLENTY OF SUNSHINE.
THE WEATHER SHOULD BE RATHER COMFORTABLE AND PLEASANT WITH
COOLER NLY WINDS AND LOW HUMIDITY...WITH TEMPS GENERALLY IN THE
70S. CLR/CALM CONDS WED NIGHT SHOULD ALLOW OVERNIGHT LOWS TO FALL
INTO THE LOW-MID 40S ACRS THE NRN TIER...AND LOW-MID 50S IN THE
SOUTH. SOME OF THE USUAL COLD SPOTS IN THE NRN MTNS COULD DIP
INTO THE UPPER 30S.
&&
.LONG TERM /THURSDAY THROUGH MONDAY/...
A DEEP CLOSED LOW MOVG ACRS THE PACIFIC NW AND NRN ROCKIES WILL
ALLOW THE CENTRAL PLAINS UPPER RIDGE TO SLIDE EWD WITH RISING HGTS
EXPECTED DOWNSTREAM OVER THE ERN CONUS. CONSENSUS OF MODEL AND
ENSEMBLE DATA CONTINUES TO BUILD THE RIDGE TO 588+DM THRU THE
WEEKEND WITH THE FIRST TASTE OF SUMMERTIME HEAT/HUMIDITY ARRIVING
ON SCHEDULE.
LLVL S-SWLY RETURN FLOW AROUND SFC HIGH PRES DRIFTING OFF THE EAST
COAST WILL BRING AN INCREASE IN LLVL MSTR THRU THE END OF THE WORK
WEEK...WITH JUST A SLGT CHC FOR AN AFTN POP-UP/AIRMASS TYPE SHOWER
OR TSTM ON FRI.
ABOVE NORMAL 500 HPA HEIGHTS OVERSPREAD THE COMMONWEALTH THIS
WEEKEND. THIS SHOULD TRANSLATE INTO WARMER-THAN-NORMAL TEMPS WITH
THE GFS-BASED MOS GUID MORE BULLISH THAN THE EC MOS ON THE HEAT.
PATTERN ALSO HAS A RING-OF-FIRE LOOK TO IT SO WILL NEED TO WATCH
FOR MCS ACTIVITY/RIDGE ROLLERS.
&&
.AVIATION /11Z TUESDAY THROUGH SATURDAY/...
QUASI STATIONARY BOUNDARY IS CURRENTLY MEADERING IN THE NW CORNER
OF THE STATE. WEAK SHOWERS ARE MAKING THERE WAY ACROSS THE
NORTHERN HALF OF THE STATE. ANY SHOWERS ARE NOT REDUCING
CONDITIONS. LOW LEVEL MOISTURE HAS CREPT UP INTO THE SOUTHEASTERN
CORNER OF THE STATE. IFR VSBYS AT LNS SHOULD CONTINUE FOR THE NEXT
FEW HOURS BUT SHOULD LIFT BY 15Z AT THE LATEST. AS THE BOUNDARY
MOVES TO THE SOUTH SCATTERED SHRA/TSRA SHOULD DEVELOP THIS AFTN.
VFR CONDS WILL PREDOMINATE...WITH BRIEF VSBY REDUCTION POSSIBLE
WITH ANY SHRA/TSRA. CURRENT MODELS SHOW ANY PRECIPITATION COULD
LINGER ALONG THE MASON DIXON LINE...AND AT LNS...MDT AND JST
THROUGH 06Z WEDNESDAY. IFR CIGS AND VSBYS WILL AGAIN BE A
POSSIBILITY TONIGHT.
OUTLOOK...
WED...EARLY AM LGT RAIN/LOW CIGS POSSIBLE JST/AOO.
THU...NO SIG WX EXPECTED.
FRI-SAT...ISOLD PM TSRA IMPACTS POSSIBLE.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...STEINBUGL
NEAR TERM...STEINBUGL
SHORT TERM...STEINBUGL
LONG TERM...STEINBUGL
AVIATION...FITZGERALD/CERU
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
542 AM EDT TUE JUN 18 2013
.SYNOPSIS...
THE PERSISTENT JUNE PATTERN OF BROAD TROUGHING OVER THE MID-
ATLANTIC AND NORTHEAST STATES IS FORECAST TO TRANSITION AND BE
REPLACED BY A SUMMERTIME UPPER LEVEL RIDGE MIGRATING EASTWARD
FROM THE PLAINS. A SLIGHTLY COOLER AND LESS HUMID AIRMASS WILL
FOLLOW IN THE WAKE OF A COLD FRONT TONIGHT INTO THURSDAY.
INCREASING HEAT AND HUMIDITY WILL ARRIVE ON SCHEDULE WITH THE
OFFICIAL START OF ASTRONOMICAL SUMMER...AND LAST INTO THE
UPCOMING WEEKEND.
&&
.NEAR TERM /THROUGH TONIGHT/...
BELT OF STRONGER MID-LVL FLOW ON THE SRN EDGE OF SHORTWAVE TROUGH
MOVG EWD FROM QUEBEC TO THE MARITIMES WILL SHIFT EWD ACRS NEW
ENGLAND THIS MORNING. AN ATTENDANT SFC COLD FRONT DRAPED ALONG THE
LWR LKS IS TEAMING WITH A WELL-DEFINED 300MB JET ENTRANCE REGION
TO MAINTAIN A CLUSTER SHOWERS/TSTMS OVER NW PA...WITH A FEW LONE
CELLS CROSSING LK ERIE. THE LATEST MESO MODELS CONTINUE TO WEAKEN
THIS AREA OF PCPN AS IT SHIFTS EWD ACRS MCKEAN CO THRU 12Z. OUTSIDE
OF THE NW MTNS...MOST AREAS SHOULD REMAIN DRY THRU DAYBREAK.
IR SATL LOOP SHOWS A SHIELD OF LYRD MID-HIGH CLOUDS SPREADING NEWD
ACRS CNTRL PA. THESE CLOUDS ARE ASSOCD WITH A SHORTWAVE LIFTING
THRU THE TN VLY AND WEAK SFC LOW ADVANCING EWD TOWARD THE CNTRL
MID-ATLC COAST. ANOTHER COMPACT SHORTWAVE IS CURRENTLY ROTATING
ACRS MN..AND WILL TRACK SEWD INTO THE LWR-MID OH VLY BY THIS
AFTN. THE APPROACHING SHORTWAVE ENERGY /FROM THE SW/ AND
AFOREMENTIONED SFC COLD FRONT /FROM THE NW/ SHOULD PROVIDE
SUFFICIENT FORCING/LIFT TO FUEL SCT TO NMRS TSTM DEVELOPMENT INTO
THE AFTN. HOWEVER THERE IS SOME QUESTION AS TO WHERE THE BEST
LOCATION/AERIAL CVRG WILL BE. THE LATEST HRRR AND 00Z SPC WRF/SSEO
HIGHLIGHT THE AREA SOUTH OF I-80...WITH THE HRRR SHOWING A NOTABLE
INCREASE IN CONVECTION AROUND THE 17-18Z TIMEFRAME.
THE SVR THREAT APPEARS MARGINAL DUE TO WEAK/MODEST INSTABILITY.
HOWEVER I CANT RULE OUT A FEW ORGANIZED STORMS GIVEN 35-40 KT OF
EFFECTIVE BULK SHEAR. COULD ALSO SEE SOME LOCALLY HEAVY RAINS
WITH THE MAIN SURGE OF ANOMALOUS PWATS OVER SOUTHEAST PA. THE
LATER ARRIVING MESO GUIDANCE SEEMS TO BE FORMING A CONSENSUS THAT
THE SRN 1/2 OF THE CWA SHOULD SEE THE MOST ACTIVITY COINCIDENT
WITH PEAK HEATING. AS SUCH...EXPECT TSTM CVRG TO WANE/TAPER OFF
WITH THE ONSET OF NIGHTFALL/SWD MVMT OF COLD FRONT.
THE FRONT WILL PUSH SOUTH ACRS THE CWA BY LATER TONIGHT WITH MUCH
DRIER/BELOW NORMAL PWAT AIR ARRIVING FROM THE NORTH. WILL HOLD
ONTO SOME LOW POPS ALONG THE MASON DIXON LINE INTO EARLY WEDNESDAY
MORNING BUT MOST AREAS SHOULD BE DRY AFT 06Z...ESPECIALLY TO THE
NORTH OF THE TURNPIKE.
&&
.SHORT TERM /WEDNESDAY THROUGH WEDNESDAY NIGHT/...
HIGH PRES WILL PREVAIL ON WEDNESDAY BRINGING PLENTY OF SUNSHINE.
THE WEATHER SHOULD BE RATHER COMFORTABLE AND PLEASANT WITH
COOLER NLY WINDS AND LOW HUMIDITY...WITH TEMPS GENERALLY IN THE
70S. CLR/CALM CONDS WED NIGHT SHOULD ALLOW OVERNIGHT LOWS TO FALL
INTO THE LOW-MID 40S ACRS THE NRN TIER...AND LOW-MID 50S IN THE
SOUTH. SOME OF THE USUAL COLD SPOTS IN THE NRN MTNS COULD DIP
INTO THE UPPER 30S.
&&
.LONG TERM /THURSDAY THROUGH MONDAY/...
A DEEP CLOSED LOW MOVG ACRS THE PACIFIC NW AND NRN ROCKIES WILL
ALLOW THE CENTRAL PLAINS UPPER RIDGE TO SLIDE EWD WITH RISING HGTS
EXPECTED DOWNSTREAM OVER THE ERN CONUS. CONSENSUS OF MODEL AND
ENSEMBLE DATA CONTINUES TO BUILD THE RIDGE TO 588+DM THRU THE
WEEKEND WITH THE FIRST TASTE OF SUMMERTIME HEAT/HUMIDITY ARRIVING
ON SCHEDULE.
LLVL S-SWLY RETURN FLOW AROUND SFC HIGH PRES DRIFTING OFF THE EAST
COAST WILL BRING AN INCREASE IN LLVL MSTR THRU THE END OF THE WORK
WEEK...WITH JUST A SLGT CHC FOR AN AFTN POP-UP/AIRMASS TYPE SHOWER
OR TSTM ON FRI.
ABOVE NORMAL 500 HPA HEIGHTS OVERSPREAD THE COMMONWEALTH THIS
WEEKEND. THIS SHOULD TRANSLATE INTO WARMER-THAN-NORMAL TEMPS WITH
THE GFS-BASED MOS GUID MORE BULLISH THAN THE EC MOS ON THE HEAT.
PATTERN ALSO HAS A RING-OF-FIRE LOOK TO IT SO WILL NEED TO WATCH
FOR MCS ACTIVITY/RIDGE ROLLERS.
&&
.AVIATION /09Z TUESDAY THROUGH SATURDAY/...
REGIONAL RADAR LOOP THIS EVENING SHOWS SHRA/TSRA ACROSS THE LOWER
GRT LKS IN ASSOCIATION WITH A SLOW-MOVING COLD FRONT. AS THIS
FRONT WORKS SE...A LATE NIGHT SHRA IS POSSIBLE OVR NORTHERN PA.
HOWEVER...THE BIGGEST AVIATION CONCERN TONIGHT IS THE POSSIBILITY
OF FOG AT BFD...MDT AND LNS...ESPECIALLY AT THE MDT AND LNS WHERE
RAIN HAS FALLEN. COUPLE THIS WITH MCLEAR SKIES...A LGT WIND AND WET
GROUND ALL FAVOR DEVELOPMENT OF FOG OVERNIGHT.
CURRENT SAT SHOT SHOWS CIRRUS MOVING OVER THE REGION...THIS WILL
REDUCE THE DEVELOPMENT AND THE SEVERITY OF ANY FOG/MIST. THE
CLEARING SKIES OVER BFD HAVE ALLOWED FOR IFR CONDITIONS TO
DEVELOP...OUT AHEAD OF THE APPROACHING FRONT. MVFR CONTINUES AT
LNS AND MVFR SHOULD DEVELOP AT MDT. IFR REMAINS POSSIBLE AT
MDT...LNS AND IPT. A THICK LAYER OF MID CLOUDS HAS DEVELOPED OVER
THE CENTRAL TAF SITES AND SHOULD NEGATE ANY FOG FORMATION.
ANY FOG THAT MANAGES TO FORM OVERNIGHT SHOULD BURN OFF WITHIN A
COUPLE HRS AFTER SUNRISE. FOCUS WILL THEN SHIFT TOWARD SCT
SHRA/TSRA DEVELOPING TUES AFTN...AS COLD FRONT WORKS SOUTH ACROSS
THE STATE. ALTHOUGH VFR CONDS WILL PREDOMINATE...A BRIEF VSBY
REDUCTION IS POSSIBLE WITH ANY SHRA/TSRA. CURRENT MODELS SHOW ANY
PRECIPITATION COULD LINGER ALONG THE MASON DIXON LINE...AND AT
LNS...MDT AND JST THROUGH 06Z WEDNESDAY. IFR CIGS AND VSBYS WILL
AGAIN BE A POSSIBILITY TOMORROW NIGHT.
OUTLOOK...
WED...EARLY AM LGT RAIN/LOW CIGS POSSIBLE JST/AOO.
THU...NO SIG WX EXPECTED.
FRI-SAT...ISOLD PM TSRA IMPACTS POSSIBLE.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...STEINBUGL
NEAR TERM...STEINBUGL
SHORT TERM...STEINBUGL
LONG TERM...STEINBUGL
AVIATION...FITZGERALD/CERU
AREA FORECAST DISCUSSION
NWS GREENVILLE-SPARTANBURG SC
713 PM EDT WED JUN 19 2013
.SYNOPSIS...
COOLER HIGH PRESSURE CENTERED NEAR NEW YORK STATE WILL RIDGE
SOUTHWARD TONIGHT AND THURSDAY. THIS HIGH WILL DRIFT TO NEAR BERMUDA
AND INTO NEXT WEEK AS AN UPPER RIDGE BUILDS IN FROM THE WEST AS
TEMPERATURES SLOWLY RISE.
&&
.NEAR TERM /THROUGH THURSDAY/...
2315 UTC UPDATE...POPS WERE ADJUSTED PER RADAR TRENDS...FAVORING THE
NORTHERN NC MOUNTAINS...AND THE NE GA MOUNTAINS. WINDS WERE UPDATED
WITH A BLEND OF THE LATEST NAM AND ADJMAV GUIDANCE. SKY COVER WAS
UPDATED FROM SATELLITE IMAGERY.
AS OF 215 PM...A WEAK SHORT WAVE TROUGH IS FORECAST TO MOVE THROUGH
THE AREA FROM NW TO SE LATE THIS AFTERNOON AND EARLY TONIGHT. THE
BEST FORCING WILL BE OVER THE FAR EASTERN AREAS. HENCE...THE MODELS
SHOW SOME LIGHT QPF RESPONSE THERE. THE LATEST HRRR SHOWS THE MOST
SHOWER COVERAGE FROM THE NORTHERN MOUNTAINS...EAST THROUGH THE
NORTHERN NC PIEDMONT. WILL MAKE A LAST MINUTE ADJUSTMENT ON THE POP
FIELD TO REFLECT THAT IDEA. WIDELY SCT SHOWERS/THUNDERSTORMS ARE
EXPECTED ELSEWHERE THROUGH THE MOUNTAINS DURING THE MID TO LATE
AFTERNOON HOURS DUE TO WEAK UPSLOPE FLOW. CAPES SHOULD GENERALLY
STAY BELOW 1000J AS SOMEWHAT LOWER DEWPOINTS CONTINUE TO ADVECT INTO
THE REGION...SO NO SEVERE THREAT. THE SHOWERS ARE EXPECTED TO
DISSIPATE DURING EVENING.
OTHERWISE...THE OVERNIGHT SHOULD BE QUIET. MODEL TIME HEIGHTS SHOW
LOW LEVEL MOISTURE INCREASING TOWARD SUNRISE AS MOISTURE FROM
ATLANTIC ADVECTS INTO THE AREA. THEREFORE...EXPECT A PERIOD OF LOW
CLOUDINESS EARLY THU...ESPECIALLY EAST OF I-26. ON THU...HIGH
PRESSURE LOCATED OFF THE NEW ENGLAND COAST WILL REMAIN RIDGED INTO
THE AREA PRODUCING AN EASTERLY WIND FLOW IN THE SOUTHERN
APPALACHIANS. THE UPSLOPE FLOW IN THE MOUNTAINS SHOULD PRODUCE
SCATTERED SHOWERS AND THUNDERSTORMS DURING THE AFTERNOON HOURS.
USING A BLEND OF MODELS PRODUCES MAX TEMPS ABOUT A CATEGORY BELOW
AVERAGE ON THU.
&&
.SHORT TERM /THURSDAY NIGHT THROUGH SATURDAY/...
AS OF 210 PM EDT WED...SHORT RANGE MODELS AGREE THAT THE REGION WILL
REMAIN UNDER A WEAK MID LEVEL TROUGH...WITH RIDGING ACROSS THE
SOUTHERN PLAINS AND ATLANTIC. AT THE SFC...A STATIONARY FRONT AND
POSSIBLE FRONTAL WAVE WILL REMAIN ACROSS THE COASTAL PLAIN OF THE
CAROLINAS. WEAK SFC RIDGING MAY REMAIN ACROSS THE SOUTHERN
APPALACHIAN REGION. GIVEN THE SFC PATTERN...I WILL INDICATE
PERSISTENT NE WINDS ACROSS THE FOOTHILLS AND PIEDMONT FOR FRIDAY AND
SATURDAY. A BLEND OF MODEL GUIDANCE INDICATES THAT SKY COVER WILL
REMAIN PARTLY TO MOSTLY CLOUDY THROUGH THE PERIOD. THE COMBINATION
OF NE WINDS AND CLOUD COVER SHOULD YIELD TEMPERATURES 3 TO 5 DEGREES
BELOW NORMAL. OVERALL...THE CHCS OF SHRA AND TSRA APPEARS
UNFAVORABLE WITHIN THE CORRIDOR OF DEEP NE FLOW. IN FACT...MODEL
CAPE FIELDS INDICATE LITTLE TO NO VALUES FOR SFC BASED PARCELS
BETWEEN THE EAST FACING MTN SLOPES TO THE WESTERN PIEDMONT. I WILL
INDICATE SCHC POPS FOR TS ACROSS THE EXTREME WESTERN NC MTNS ON FRI
AND SAT. BY SAT...LLVL WINDS MAY VEER NE...POSSIBLY ALLOWING WEAK
INSTABILITY ACROSS NE GA AND THE EASTERN PIEDMONT DURING THE LATE
AFTERNOON.
&&
.LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/...
AS OF 240 PM EDT WED...A 591 DM H5 RIDGE WILL REMAIN DOMINANT OVER
THE SE THROUGH THE MEDIUM RANGE PERIOD. ANTICIPATE A MAINLY DIURNAL
TREND OF ISOLD TO SCATTERED AFTERNOON POPS THROUGH THE PERIOD...WITH
THE MTNS BEING THE PRIMARY FOCUS. THE GFS IS THE MOST AGGRESSIVE IN
BRINGING AN INVERTED COASTAL TROUGH BACK INLAND ALONG THE SAVANNAH
ON SATURDAY...BUT THE OTHER OPERATIONAL AND ENSEMBLE MEAN SOLUTIONS
KEEP THE SYSTEM ALONG THE IMMEDIATE COAST WITH THE RIDGE PERSISTING
OVER THE WRN CAROLINAS. THE DIURNAL PATTERN OF ISOLD TO SCT SHOWERS
AND THUNDERSTORMS SHOULD THUS CONTINUE SUN THROUGH TUE...WITH
TEMPERATURES STEADILY WARMING UNDER THE UPPER RIDGE. EXPECT MAXES TO
REACH CLIMATE NORMALS BY SUNDAY AND THEN EXCEED THEM MON AND TUE.
THE UPPER RIDGE WILL BREAK DOWN IN MID WEEK AS A UPPER TROUGH FORMS
OVER THE EAST COAST FOR THE SECOND HALF OF NEXT WEEK. THE GFS IS A
BIT MORE PROGRESSIVE IN BRINGING THE TROUGH IN SOONER BY LATE WED OR
WED NIGHT AS OPPOSED TO THUR OR FRI ON THE ECMWF. TEMPS ARE EXPECTED
TO COOL SOME AS THIS TROUGH SETS UP WITH MORE CLOUDS AND HIGHER POPS.
&&
.AVIATION /23Z WEDNESDAY THROUGH MONDAY/...
AT KCLT...CONVECTION DOES NOT APPEAR LIKELY THIS EVENING AS ACTIVITY
IS FOCUSED CLOSER TO A BOUNDARY IN THE MOUNTAINS...AND HEATING WILL
ABATE. A BLEND OF GUIDANCE FAVORS A VERY LOW LOW MVFR CIG BY
DAYBREAK...BUT NO VSBY RESTRICTION. CONVECTION ON THURSDAY IS
EXPECTED TO BE LIMITED TO MOUNTAINOUS TERRAIN WELL TO OFF TO THE
NORTHWEST. WINDS WILL BE LIGHT NE OVERNIGHT...APPROACHING 10 KNOTS
ON THURSDAY.
ELSEWHERE...EVENING CONVECTION IS EXPECTED TO BE LIMITED MAINLY TO
THE MOUNTAINS NEAR A WEAK FRONT. A CONSENSUS OF MODEL GUIDANCE
FAVORS LOW MVFR COGS TOWARD DAYBREAK...EXCEPT AT KAND WHERE CLOUD
COVER IS EXPECTED TO BE MORE LIMITED. BLENDED MODEL DATA SUPPORTS
DAYBREAK MVFR VSBY RESTRICTIONS IN THE NC MOUNTAINS...INCLUDING
KAVL...AND A LOW VFR RESTRICTION AT KAND. LIGHT NE WINDS WILL
PERSIST OVERNIGHT IN THE FOOTHILLS...WITH LIGHT AND VARIABLE
EXPECTED AT KAVL. NE WINDS WILL APPROACH 10 KNOTS IN THE FOOTHILLS
THURSDAY...WHILE SE WINDS APPROACH 10 KNOTS AT KAVL.
OUTLOOK...AFTERNOON AND EVENING CONVECTION IS EXPECTED...WITH THE
BEST COVERAGE OVER THE MOUNTAINS. EARLY MORNING STRATUS IS POSSIBLE
EACH DAY...ACCOMPANIED BY VALLEY FOG IN THE MOUNTAINS.
CONFIDENCE TABLE...
23-05Z 05-11Z 11-17Z 17-23Z
KCLT HIGH 100% HIGH 98% HIGH 92% HIGH 100%
KGSP HIGH 100% HIGH 85% HIGH 83% HIGH 100%
KAVL HIGH 100% HIGH 94% HIGH 91% HIGH 100%
KHKY HIGH 100% HIGH 94% HIGH 90% HIGH 100%
KGMU HIGH 100% HIGH 85% HIGH 82% HIGH 100%
KAND HIGH 100% HIGH 100% HIGH 85% HIGH 100%
THE PERCENTAGE REFLECTS THE NUMBER OF GUIDANCE MEMBERS AGREEING
WITH THE SCHEDULED TAF ISSUANCE FLIGHT RULE CATEGORY. COMPLETE
HOURLY EXPERIMENTAL AVIATION FORECAST CONSISTENCY TABLES AND ENSEMBLE
FORECASTS ARE AVAILABLE AT THE FOLLOWING LINK: (MUST BE LOWER CASE)
WWW.WEATHER.GOV/GSP/AVIATION_TABLES
&&
.GSP WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
NC...NONE.
SC...NONE.
&&
$$
SYNOPSIS...DEO
NEAR TERM...JAT/LG
SHORT TERM...NED
LONG TERM...DEO
AVIATION...JAT
AREA FORECAST DISCUSSION...UPDATED
NWS NASHVILLE TN
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 NASHVILLE TN
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.
&&
$$
21
AREA FORECAST DISCUSSION...UPDATED
NWS AMARILLO TX
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 SAN ANGELO TX
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 / 5 0 0 0 0
JUNCTION 71 94 71 93 71 / 0 0 0 0 0
&&
.SJT WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
HUBER
AREA FORECAST DISCUSSION...UPDATED
NWS AMARILLO TX
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 SAN ANGELO TX
1251 AM CDT TUE JUN 18 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 CONTINUE SHOWERS AND THUNDERSTORMS ACROSS SOME
OF WEST CENTRAL TEXAS TONIGHT AND FOR MUCH OF WEST CENTRAL TEXAS
AGAIN TOMORROW AFTERNOON. THE NAM INDICATES THE BEST CHANCE FOR
THUNDERSTORMS TONIGHT WILL BE ACROSS OUR SOUTHERN COUNTIES.
HOWEVER...RADAR TRENDS OVER THE LAST COUPLE HOURS INDICATE THE
THUNDERSTORM COMPLEX OVER THE CONCHO VALLEY IS WEAKENING. THUS...I
DECIDED NOT TO INCLUDE ANY THUNDER IN THE SONORA...JUNCTION...OR
BRADY TERMINALS. IF THESE TERMINALS DO HAVE A THUNDERSTORM IT WILL
LIKELY BE VERY SHORT LIVED. FOR SAN ANGELO...I DID INCLUDE A TEMPO
GROUP FOR THUNDER FROM 06Z TO 08Z...GIVEN CURRENT THUNDERSTORM
COMPLEX THERE. FOR TOMORROW AFTERNOON...I DECIDED TO INCLUDE
PROB30 GROUPS FOR THUNDER AT ALL FIVE TERMINALS. THE NAM
GENERATES A BROAD QPF AREA ACROSS MOST OF WEST CENTRAL TEXAS
TOMORROW AFTERNOON. SO...I BELIEVE THE PROB30 GROUPS FOR ALL FIVE
TERMINALS LOOK REASONABLE. THE NAM ALSO BRINGS A WEAK COLD FRONT
INTO WEST CENTRAL TEXAS TOMORROW AND STALLS IT NEAR A STERLING
CITY TO BROWNWOOD LINE BY TOMORROW AFTERNOON. THUS...LOOK FOR
LIGHT SURFACE WINDS TOMORROW.
HUBER
&&
.PREV DISCUSSION... /ISSUED 1125 PM CDT MON JUN 17 2013/
UPDATE...
SEVERE THUNDERSTORM WATCH NUMBER 323 HAS EXPIRED. PLUS...SATELLITE
IMAGERY INDICATE A MESOSCALE CONVECTIVE COMPLEX HAS MOVED INTO
OUR WESTERN COUNTIES. WE HAVE COORDINATED WITH THE RIVER FORECAST
CENTER...AND WE BELIEVE THE THREAT OF RIVER FLOODING REMAINS LOW
AT THIS TIME. HOWEVER...HEAVY RAINFALL IS LIKELY WITH THIS
COMPLEX. SO...FLASH FLOODING IS A POSSIBILITY. BASED ON SATELLITE
AND RADAR TRENDS OVER THE LAST COUPLE HOURS...I DECIDED TO
INCREASE RAIN CHANCES ACROSS OUR CONCHO VALLEY AND HEARTLAND
COUNTIES FOR THE REMAINDER OF TONIGHT. THE LATEST RUC AND NAM DATA
INDICATE THE COMPLEX WILL LIKELY CONTINUE TO MOVE SLOWLY SOUTH FOR
THE REMAINDER OF TONIGHT. SO...I ALSO INCREASED RAIN CHANCES
ACROSS AT LEAST THE NORTHERN PARTS OF OUR NORTHERN EDWARDS PLATEAU
COUNTIES AND OUR NORTH WEST HILL COUNTRY COUNTIES. THE LATEST
ALPHANUMERIC PRODUCTS REFLECT THESE CHANGES.
HUBER
PREV DISCUSSION... /ISSUED 730 PM CDT MON JUN 17 2013/
UPDATE...
LATEST WSR-88D DATA INDICATE THUNDERSTORMS ARE SLOWLY MOVING SOUTH
ACROSS THE BIG COUNTRY. BASED ON THE SEVERE HISTORY OF SOME OF
THESE THUNDERSTORMS...AND AFTER COORDINATION WITH SPC...WE DECIDED TO
EXTEND THE SEVERE THUNDERSTORM WATCH SOUTH TO INCLUDE OUR NORTHERN
THREE CONCHO VALLEY COUNTIES AND OUR NORTHERN HEARTLAND COUNTIES.
I UPDATED OUR HAZARD GRID TO INCLUDE THESE NEW COUNTIES AND ISSUED
A NEW WATCH COUNTY NOTIFICATION FOR SEVERE THUNDERSTORM WATCH 323.
OUR LATEST ZONE PRODUCT REFLECTS THIS UPDATE.
HUBER
PREV DISCUSSION... /ISSUED 655 PM CDT MON JUN 17 2013/
DISCUSSION...
LOOK FOR THUNDERSTORMS ACROSS THE BIG COUNTRY THIS EVENING AND
STRATUS TO BRING MVFR CEILINGS BACK TO THE NORTHWEST HILL COUNTRY
LATER TONIGHT. SEE AVIATION BELOW FOR DETAILS.
AVIATION...
LOOK FOR CHALLENGING FLIGHT WEATHER CONDITIONS TO CONTINUE ACROSS
THE BIG COUNTRY THIS EVENING. THUNDERSTORMS DEVELOPED EARLIER THIS
AFTERNOON ALONG AN OLD OUTFLOW BOUNDARY JUST NORTH OF INTERSTATE
20 ACROSS THE BIG COUNTRY. THE RUC INDICATES WE COULD HAVE AN
MESOSCALE CONVECTIVE COMPLEX MOVE INTO WEST CENTRAL TEXAS FROM THE
NORTHWEST LATER THIS EVENING. HOWEVER...MY CONFIDENCE AS TO WHERE
THIS COMPLEX MAY MOVE ACROSS WEST CENTRAL TEXAS...I DECIDED NOT TO
INCLUDE ANY THUNDER IN ANY OF THE TERMINALS AT THIS TIME...EXCEPT
FOR ABILENE. LATER TONIGHT...THE NAM BRING STRATUS AND MVFR
CEILINGS BACK TO JUNCTION. FOR TOMORROW AFTERNOON...LOOK FOR
THUNDERSTORMS TO AGAIN DEVELOP ACROSS MUCH OF WEST CENTRAL TEXAS.
HUBER
PREV DISCUSSION... /ISSUED 354 PM CDT MON JUN 17 2013/
SHORT TERM...
/TONIGHT INTO TUESDAY/
A CHANCE OF THUNDERSTORMS TONIGHT INTO TUESDAY...MAINLY OVER THE
BIG COUNTRY...BUT ALL OF WEST CENTRAL TEXAS HAS A SLIGHT CHANCE
OF STORMS.
THUNDERSTORMS WERE DEVELOPING IN AN ENHANCED CUMULUS FIELD IN THE
BIG COUNTRY AT 3 PM...ASSOCIATED WITH REMNANT OUTFLOW BOUNDARY
FROM A MORNING THUNDERSTORM COMPLEX. EXPECT SCATTERED
THUNDERSTORMS TO DEVELOP AND MOVE SLOWLY EAST OR SOUTHEAST OVER
THE BIG COUNTRY THIS AFTERNOON AND EVENING. A SECOND COMPLEX OF
STORMS WILL LIKELY DEVELOP ALONG A WEAK COLD FRONT...EAST OF
LUBBOCK THIS EVENING...THEN MOVE SLOWLY SOUTH OR SOUTHEAST INTO THE
BIG COUNTRY AND CONCHO VALLEY. IT MAY BE LATE EVENING FOR STORMS
TO AFFECT SOUTHERN AREAS FROM SAN ANGELO TO BROWNWOOD.
WITH SB CAPES OF 3000 J/KG...AND 0-6 KM SHEARS UP TO 40 KTS (BIG
COUNTRY)THIS EVENING...SOME SEVERE STORMS POSSIBLE. SPC DAY 1
SEVERE WEATHER OUTLOOK HAS A SLIGHT RISK OF SEVERE STORMS IN THE
BIG COUNTRY...CONCHO VALLEY AND NORTHERN HEARTLAND.
THERE IS A SIMILAR SETUP FOR TUESDAY...WITH DISSIPATING FRONT IN
THE BIG COUNTRY BEING THE FOCAL POINT FOR SHOWER AND
THUNDERSTORM DEVELOPMENT. AGAIN A FEW STORMS COULD BE SEVERE WITH
CAPES OVER 2500 J/KG IN THE AFTERNOON.
04
LONG TERM...
THE MAJORITY OF THE LONG TERM PORTION OF THE FORECAST WILL BE
HIGHLIGHTED BY HOT AND DRY CONDITIONS AS THE SUBTROPICAL RIDGE
BECOMES THE DOMINANT FEATURE ACROSS THE CENTRAL CONUS.
SCATTERED CONVECTION IS EXPECTED TO BE ONGOING LATE TUESDAY
AFTERNOON AND SHOULD LINGER INTO THE EVENING HOURS. LOW POPS
WERE INCLUDED FOR ALL OF WEST CENTRAL TEXAS. MOST OF THIS ACTIVITY
SHOULD WANE BY 9 PM BUT THERE IS SOME INDICATION THAT A DECENT MID
LEVEL WAVE DIVING SOUTHEAST ACROSS THE ROCKIES WILL AID IN THE
DEVELOPMENT OF AN MCS PROPAGATING OUT OF THE HIGH PLAINS AND INTO
WESTERN NORTH TX. I DID INCLUDE LOW RAIN CHANCES FOR WEDNESDAY
MORNING...GENERALLY NORTH AND EAST OF ABILENE THROUGH 18Z TO
CAPTURE THIS POTENTIAL. HOWEVER...ONCE THIS SYSTEM MOVES
EAST...RAIN CHANCES LOOK TO BECOME VERY SCARCE THROUGH THE
WEEKEND.
TEMPS WILL WARM INTO THE MID 90S ON WEDNESDAY AFTERNOON...CREEPING
INTO THE UPPER 90S FOR THURSDAY AND FRIDAY. I WOULD NOT RULE OUT
THE POSSIBILITY THAT A FEW AREAS COULD REACH TRIPLE DIGITS BUT I
THINK THIS WILL BE THE EXCEPTION RATHER THAN THE RULE. EXPECT MIN
TEMPS DURING THIS TIME IN THE LOW/MID 70S WITH BRIEF STRATUS
EPISODES OVER THE SOUTHEAST COUNTIES DURING THE LATE NIGHT AND
MORNING HOURS. DEEP DIURNAL MIXING WILL RESULT IN DECREASING
DEWPOINTS DURING THE LATTER HALF OF THE WORK WEEK...SUGGESTING
THAT THE AFTERNOON CU FIELD WILL BECOME MORE SPARSE.
THE 12Z ECMWF HAS COME MORE IN LINE WITH THE RECENT RUNS OF THE
GFS/GEM REGARDING THE HANDLING OF THE REMNANTS OF TD 2. THE 00Z
ECMWF WAS BRINGING A PERSISTENT MID LEVEL WAVE UP THE RIO GRANDE
AND LIFTING IT NORTH ACROSS WEST TX OVER THE WEEKEND...VERY
SIMILAR TO WHAT WAS OBSERVED THIS PAST WEEKEND. HOWEVER...THE
LATEST RUN IS KEEPING ANY REMNANTS WELL SOUTH OF THE AREA...
ADVECTING IT NEARLY DUE WEST INTO CENTRAL MEXICO AND MORE IN LINE
WITH THE TPC FORECAST. GIVEN THE POOR ORGANIZATION OF THIS STORM
AND ITS PROXIMITY TO LAND...THE LATEST SOLUTIONS LOOK VERY
REASONABLE. THUS...NO IMPACT IS EXPECTED ANYWHERE NEAR WEST
CENTRAL TX.
THE MEDIUM RANGE MODELS ALL INDICATE A STRONG SHORTWAVE TROUGH
MOVING ACROSS THE NORTHWEST CONUS FRIDAY/SATURDAY BUT THE
SUBTROPICAL RIDGE IS EXPECTED TO HOLD STRONG OVER THE SOUTHERN
PLAINS. HOWEVER...MID LEVEL HEIGHTS ARE EXPECTED TO LOWER SOMEWHAT
AS THIS SYSTEM MOVES ACROSS THE PLAINS AND FLATTENS THE RIDGE.
JOHNSON
&&
.PRELIMINARY POINT TEMPS/POPS...
ABILENE 72 95 75 96 73 / 30 10 5 0 0
SAN ANGELO 73 96 75 97 74 / 20 5 5 0 0
JUNCTION 72 93 73 94 73 / 20 5 5 5 5
&&
.SJT WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
HUBER/04/JOHNSON
AREA FORECAST DISCUSSION...UPDATED
NWS AMARILLO TX
1158 PM CDT MON JUN 17 2013
.AVIATION.../06Z TAFS/
SHRA/TSRA ONGOING AND MAY IMPACT THE TERMINALS THROUGH 10Z. THERE IS
A SMALL THREAT FOR BRIEF MVFR CONDITIONS IF THERE IS A DIRECT IMPACT.
ANOTHER ROUND OF -TSRA WILL DEVELOP LATE TUESDAY AFTERNOON. HAVE
MODERATE TO HIGH CONFIDENCE THAT KDHT AND KGUY WILL HAVE VCTS AFTER
00Z AND 01Z, RESPECTIVELY. THERE IS A CHANCE KAMA COULD BE SEE VCTS
AFTER 05Z, BUT SINCE THIS IS AT THE VERY END OF THIS TAF PERIOD, WE
ELECTED NOT TO MENTION IN THE TAF. IF THERE IS A DIRECT IMPACT FROM
ANY TSRA, HAIL, WIND GUSTS UP TO 50 KT, AND BRIEF LIFR CONDITIONS
WILL BE POSSIBLE.
THERE IS A CHANCE FOR BRIEF MVFR/IFR CONDITIONS AT ALL TERMINALS 10Z-
15Z, BUT CONFIDENCE OF OCCURRENCE IS TOO LOW TO MENTION AT THIS TIME.
JACKSON
&&
.PREV DISCUSSION... /ISSUED 1034 PM CDT MON JUN 17 2013/
UPDATE...
HAVE MADE ADJUSTMENTS TO GRAPHICAL FORECASTS...LOWERING POPS
TONIGHT...ESPECIALLY ACROSS THE NORTHEASTERN THREE FOURTHS OF THE
FORECAST AREA. THIS AREA IS CHARACTERIZED BY A RESIDUAL RAIN-COOLED
AIRMASS FROM LAST NIGHT/S THUNDERSTORMS. THUNDERSTORMS HAVE BEEN
SLOW TO MOVE INTO OR DEVELOP IN THIS REGION OF HIGHER STABILITY.
ALSO...PRONOUNCED INVERSION SEEN ON 00Z SOUNDING FROM KAMA INDICATES
THAT SUBSTANTIAL CAP IS IN PLACE. WILL REMOVE MENTION OF SEVERE
THUNDERSTORMS FOLLOWING EXPIRATION OF SEVERE THUNDERSTORM WATCH AT
11 PM. UPDATED TEXT PRODUCTS WILL BE ISSUED SHORTLY.
COCKRELL
PREV DISCUSSION... /ISSUED 615 PM CDT MON JUN 17 2013/
AVIATION...
WHILE VFR CONDITIONS ARE PREVAILING ACROSS THE
TERMAINAL...APPROACHING/DEVELOPING CONVECTION WILL CAUSE IMPACTS TO
EACH TERMINAL. KDHT WILL LIKELY BE IMPACTED FIRST AS CONVECTION IS
MOVING OUT OF NEW MEXICO. THE NEXT TERMINAL TO BE IMPACTED WILL
LIKELY BY KGUY THEN KAMA SOON AFTER. AS CONVECTION MOVES OVER THE
TERMINALS EXPECT LIMITED VISIBILITIES AND LOWER CEILINGS. THESE
STORMS WILL ALSO BE ABLE TO PRODUCE FREQUENT LIGHTNING...HAIL...AND
DAMAGING WINDS. HAVE INITIAL TEMPO GROUPS FOR THIS ROUND OF
CONVECTION AND WILL AMEND AS NEEDED FOR ADDITIONAL CONVECTION. BY
9...ANY RESIDUAL CONVECTION SHOULD CEASE AND LEAVE SUFFICIENT LOW
LEVEL MOISTURE FOR LOW CLOUDS TO CONTINUE TO IMPACT THE TERMINALS
UNTIL THE LATE MORNING HOURS ON THE 18TH. ANOTHER ROUND OF CONVECTION
WILL BE POSSIBLE TOMORROW AFTERNOON BUT GIVEN THE UNCERTAINTIES ON
TIME AND LOCATION OF OCCURRENCE HAVE LEFT MENTION OUT OF PREVAILING
GROUPS.
PREV DISCUSSION... /ISSUED 412 PM CDT MON JUN 17 2013/
UPDATE...
SEVERE THUNDERSTORM WATCH NUMBER 323 HAS BEEN ISSUED FOR THE CENTRAL
AND WESTERN TEXAS AND OKLAHOMA PANHANDLES UNTIL 11 PM. PRIMARY
THREATS WILL BE LARGE HAIL AND DAMAGING WIND. DUE TO SATURATED SOILS
AND HEAVY RAIN POTENTIAL...THERE WILL ALSO BE A LOCALIZED AND FLASH
FLOODING THREAT. UPDATED TEXT PRODUCTS HAVE BEEN ISSUED.
PREV DISCUSSION... /ISSUED 312 PM CDT MON JUN 17 2013/
DISCUSSION...
TODAY AND TOMORROW REMAIN ACTIVE DAYS FOR THE TEXAS AND OKLAHOMA
PANHANDLES. TEMPERATURES WERE SLOW TO COME UP THIS MORNING BUT HAVE
BEGUN TO QUICKLY RISE ACROSS THE AREA. THERE WAS SOME CONCERN THAT
THE SLOW HEATING WOULD DELAY INITIATION OF STORMS THIS AFTERNOON
HOWEVER VISIBLE SATELLITE IMAGERY IS SHOWING A MILD CU FIELD
DEVELOPING ACROSS THE EASTERN HALF OF THE PANHANDLES. ALSO
CONVECTION OVER THE NEW MEXICO MOUNTAINS HAS INITIATED ONLY ABOUT A
HOUR BEHIND WHAT WAS SHOWN IN THE 14Z RUC HRRR. AS SUCH THE PREVIOUS
FORECAST SEVERE THREAT START TIME OF 6 PM REMAINS REALISTIC. WILL
PAY CLOSE ATTENTION TO THE DEVELOPING CONVECTION ALONG THE RED RIVER
AS IT COULD BACK BUILD ALONG A SOUTHWARD PROGRESSING COLD FRONT INTO
COLLINGSWORTH COUNTY PRIOR TO 6 PM. THE SEVERE THREAT WILL LAST
UNTIL 2-3AM TUESDAY WHEN STRONG CAPPING WILL SETUP
HOWEVER...PRECIPITATION MAY LAST WELL PAST 3 AM.
SPC MESO ANALYSIS HAS SHOWN A CONTINUAL DECREASING TREND OF CIN
VALUES ACROSS THE WESTERN TEXAS AND OKLAHOMA PANHANDLES DURING THE
SAME TIME SHOWING AN INCREASE OF SBCAPE VALUES. FORECAST SBCAPE
VALUES OF 1500-2500 J/KG WITH DEEP LAYER SHEAR OF 35-40 KT CONTINUE
SUPPORT LARGE HAIL AND DAMAGING WIND AS THE PRIMARY SEVERE HAZARDS.
GIVEN SLOW STORM MOTIONS OF 15 TO 20 KTS...MOIST SOILS FROM PREVIOUS
RAINS...AND PWAT VALUES NEAR AN INCH WILL KEEP LOCALIZED AND FLASH
FLOODING AS A CONCERN WITH THESE STORMS.
TOMORROW MODELS CONTINUE TO ADVERTISE REDEVELOPMENT OF STORMS ACROSS
THE PANHANDLE. CAPE VALUES OF 1000-2000 J/KG AND DEEP SHEAR OF 35-45
KT WILL KEEP THE RISK OF SEVERE STORMS ACROSS THE PANHANDLES YET
AGAIN. THE TIME FRAME FOR STORMS TO DEVELOP WILL BE AROUND 4 PM WITH
SEVERE POTENTIAL MAXIMIZING AFTER 6 PM. STORM WILL CONTINUE THROUGH
MOST OF THE NIGHT BUT THE SEVERE RISK SHOULD SUBSIDE AFTER 3 AM.
WEDNESDAY THROUGH THE WEEKEND...UPPER LEVEL RIDGING WILL RETURN TO
THE PANHANDLES AND KEEP PRECIPITATION CHANCES LIMITED. THE RIDGE AXIS
WILL MEANDER TO THE EAST AND BACK TO THE WEST WHICH WILL OPEN UP THE
CHANCE FOR SOME PRECIP BUT HAVE KEPT THE FORECAST DRY GIVEN THE
UNCERTAINTY ON THE AXIS PLACEMENT THIS FAR OUT.
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.
&&
$$
JJ/JC
AREA FORECAST DISCUSSION
NWS SAN ANGELO TX
1125 PM CDT MON JUN 17 2013
.UPDATE...
SEVERE THUNDERSTORM WATCH NUMBER 323 HAS EXPIRED. PLUS...SATELLITE
IMAGERY INDICATE A MESOSCALE CONVECTIVE COMPLEX HAS MOVED INTO
OUR WESTERN COUNTIES. WE HAVE COORDINATED WITH THE RIVER FORECAST
CENTER...AND WE BELIEVE THE THREAT OF RIVER FLOODING REMAINS LOW
AT THIS TIME. HOWEVER...HEAVY RAINFALL IS LIKELY WITH THIS
COMPLEX. SO...FLASH FLOODING IS A POSSIBILITY. BASED ON SATELLITE
AND RADAR TRENDS OVER THE LAST COUPLE HOURS...I DECIDED TO
INCREASE RAIN CHANCES ACROSS OUR CONCHO VALLEY AND HEARTLAND
COUNTIES FOR THE REMAINDER OF TONIGHT. THE LATEST RUC AND NAM DATA
INDICATE THE COMPLEX WILL LIKELY CONTINUE TO MOVE SLOWLY SOUTH FOR
THE REMAINDER OF TONIGHT. SO...I ALSO INCREASED RAIN CHANCES
ACROSS AT LEAST THE NORTHERN PARTS OF OUR NORTHERN EDWARDS PLATEAU
COUNTIES AND OUR NORTH WEST HILL COUNTRY COUNTIES. THE LATEST
ALPHANUMERIC PRODUCTS REFLECT THESE CHANGES.
HUBER
&&
.PREV DISCUSSION... /ISSUED 730 PM CDT MON JUN 17 2013/
UPDATE...
LATEST WSR-88D DATA INDICATE THUNDERSTORMS ARE SLOWLY MOVING SOUTH
ACROSS THE BIG COUNTRY. BASED ON THE SEVERE HISTORY OF SOME OF
THESE THUNDERSTORMS...AND AFTER COORDINATION WITH SPC...WE DECIDED TO
EXTEND THE SEVERE THUNDERSTORM WATCH SOUTH TO INCLUDE OUR NORTHERN
THREE CONCHO VALLEY COUNTIES AND OUR NORTHERN HEARTLAND COUNTIES.
I UPDATED OUR HAZARD GRID TO INCLUDE THESE NEW COUNTIES AND ISSUED
A NEW WATCH COUNTY NOTIFICATION FOR SEVERE THUNDERSTORM WATCH 323.
OUR LATEST ZONE PRODUCT REFLECTS THIS UPDATE.
HUBER
PREV DISCUSSION... /ISSUED 655 PM CDT MON JUN 17 2013/
DISCUSSION...
LOOK FOR THUNDERSTORMS ACROSS THE BIG COUNTRY THIS EVENING AND
STRATUS TO BRING MVFR CEILINGS BACK TO THE NORTHWEST HILL COUNTRY
LATER TONIGHT. SEE AVIATION BELOW FOR DETAILS.
AVIATION...
LOOK FOR CHALLENGING FLIGHT WEATHER CONDITIONS TO CONTINUE ACROSS
THE BIG COUNTRY THIS EVENING. THUNDERSTORMS DEVELOPED EARLIER THIS
AFTERNOON ALONG AN OLD OUTFLOW BOUNDARY JUST NORTH OF INTERSTATE
20 ACROSS THE BIG COUNTRY. THE RUC INDICATES WE COULD HAVE AN
MESOSCALE CONVECTIVE COMPLEX MOVE INTO WEST CENTRAL TEXAS FROM THE
NORTHWEST LATER THIS EVENING. HOWEVER...MY CONFIDENCE AS TO WHERE
THIS COMPLEX MAY MOVE ACROSS WEST CENTRAL TEXAS...I DECIDED NOT TO
INCLUDE ANY THUNDER IN ANY OF THE TERMINALS AT THIS TIME...EXCEPT
FOR ABILENE. LATER TONIGHT...THE NAM BRING STRATUS AND MVFR
CEILINGS BACK TO JUNCTION. FOR TOMORROW AFTERNOON...LOOK FOR
THUNDERSTORMS TO AGAIN DEVELOP ACROSS MUCH OF WEST CENTRAL TEXAS.
HUBER
PREV DISCUSSION... /ISSUED 354 PM CDT MON JUN 17 2013/
SHORT TERM...
/TONIGHT INTO TUESDAY/
A CHANCE OF THUNDERSTORMS TONIGHT INTO TUESDAY...MAINLY OVER THE
BIG COUNTRY...BUT ALL OF WEST CENTRAL TEXAS HAS A SLIGHT CHANCE
OF STORMS.
THUNDERSTORMS WERE DEVELOPING IN AN ENHANCED CUMULUS FIELD IN THE
BIG COUNTRY AT 3 PM...ASSOCIATED WITH REMNANT OUTFLOW BOUNDARY
FROM A MORNING THUNDERSTORM COMPLEX. EXPECT SCATTERED
THUNDERSTORMS TO DEVELOP AND MOVE SLOWLY EAST OR SOUTHEAST OVER
THE BIG COUNTRY THIS AFTERNOON AND EVENING. A SECOND COMPLEX OF
STORMS WILL LIKELY DEVELOP ALONG A WEAK COLD FRONT...EAST OF
LUBBOCK THIS EVENING...THEN MOVE SLOWLY SOUTH OR SOUTHEAST INTO THE
BIG COUNTRY AND CONCHO VALLEY. IT MAY BE LATE EVENING FOR STORMS
TO AFFECT SOUTHERN AREAS FROM SAN ANGELO TO BROWNWOOD.
WITH SB CAPES OF 3000 J/KG...AND 0-6 KM SHEARS UP TO 40 KTS (BIG
COUNTRY)THIS EVENING...SOME SEVERE STORMS POSSIBLE. SPC DAY 1
SEVERE WEATHER OUTLOOK HAS A SLIGHT RISK OF SEVERE STORMS IN THE
BIG COUNTRY...CONCHO VALLEY AND NORTHERN HEARTLAND.
THERE IS A SIMILAR SETUP FOR TUESDAY...WITH DISSIPATING FRONT IN
THE BIG COUNTRY BEING THE FOCAL POINT FOR SHOWER AND
THUNDERSTORM DEVELOPMENT. AGAIN A FEW STORMS COULD BE SEVERE WITH
CAPES OVER 2500 J/KG IN THE AFTERNOON.
04
LONG TERM...
THE MAJORITY OF THE LONG TERM PORTION OF THE FORECAST WILL BE
HIGHLIGHTED BY HOT AND DRY CONDITIONS AS THE SUBTROPICAL RIDGE
BECOMES THE DOMINANT FEATURE ACROSS THE CENTRAL CONUS.
SCATTERED CONVECTION IS EXPECTED TO BE ONGOING LATE TUESDAY
AFTERNOON AND SHOULD LINGER INTO THE EVENING HOURS. LOW POPS
WERE INCLUDED FOR ALL OF WEST CENTRAL TEXAS. MOST OF THIS ACTIVITY
SHOULD WANE BY 9 PM BUT THERE IS SOME INDICATION THAT A DECENT MID
LEVEL WAVE DIVING SOUTHEAST ACROSS THE ROCKIES WILL AID IN THE
DEVELOPMENT OF AN MCS PROPAGATING OUT OF THE HIGH PLAINS AND INTO
WESTERN NORTH TX. I DID INCLUDE LOW RAIN CHANCES FOR WEDNESDAY
MORNING...GENERALLY NORTH AND EAST OF ABILENE THROUGH 18Z TO
CAPTURE THIS POTENTIAL. HOWEVER...ONCE THIS SYSTEM MOVES
EAST...RAIN CHANCES LOOK TO BECOME VERY SCARCE THROUGH THE
WEEKEND.
TEMPS WILL WARM INTO THE MID 90S ON WEDNESDAY AFTERNOON...CREEPING
INTO THE UPPER 90S FOR THURSDAY AND FRIDAY. I WOULD NOT RULE OUT
THE POSSIBILITY THAT A FEW AREAS COULD REACH TRIPLE DIGITS BUT I
THINK THIS WILL BE THE EXCEPTION RATHER THAN THE RULE. EXPECT MIN
TEMPS DURING THIS TIME IN THE LOW/MID 70S WITH BRIEF STRATUS
EPISODES OVER THE SOUTHEAST COUNTIES DURING THE LATE NIGHT AND
MORNING HOURS. DEEP DIURNAL MIXING WILL RESULT IN DECREASING
DEWPOINTS DURING THE LATTER HALF OF THE WORK WEEK...SUGGESTING
THAT THE AFTERNOON CU FIELD WILL BECOME MORE SPARSE.
THE 12Z ECMWF HAS COME MORE IN LINE WITH THE RECENT RUNS OF THE
GFS/GEM REGARDING THE HANDLING OF THE REMNANTS OF TD 2. THE 00Z
ECMWF WAS BRINGING A PERSISTENT MID LEVEL WAVE UP THE RIO GRANDE
AND LIFTING IT NORTH ACROSS WEST TX OVER THE WEEKEND...VERY
SIMILAR TO WHAT WAS OBSERVED THIS PAST WEEKEND. HOWEVER...THE
LATEST RUN IS KEEPING ANY REMNANTS WELL SOUTH OF THE AREA...
ADVECTING IT NEARLY DUE WEST INTO CENTRAL MEXICO AND MORE IN LINE
WITH THE TPC FORECAST. GIVEN THE POOR ORGANIZATION OF THIS STORM
AND ITS PROXIMITY TO LAND...THE LATEST SOLUTIONS LOOK VERY
REASONABLE. THUS...NO IMPACT IS EXPECTED ANYWHERE NEAR WEST
CENTRAL TX.
THE MEDIUM RANGE MODELS ALL INDICATE A STRONG SHORTWAVE TROUGH
MOVING ACROSS THE NORTHWEST CONUS FRIDAY/SATURDAY BUT THE
SUBTROPICAL RIDGE IS EXPECTED TO HOLD STRONG OVER THE SOUTHERN
PLAINS. HOWEVER...MID LEVEL HEIGHTS ARE EXPECTED TO LOWER SOMEWHAT
AS THIS SYSTEM MOVES ACROSS THE PLAINS AND FLATTENS THE RIDGE.
JOHNSON
&&
.PRELIMINARY POINT TEMPS/POPS...
ABILENE 70 92 72 95 75 / 60 30 30 10 5
SAN ANGELO 72 94 73 96 75 / 50 20 20 5 0
JUNCTION 73 93 72 93 73 / 20 10 20 5 0
&&
.SJT WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
HUBER/04/JOHNSON
AREA FORECAST DISCUSSION
NWS SPOKANE WA
240 PM PDT Tue Jun 18 2013
.SYNOPSIS...
Scattered showers and a few thunderstorms will continue Tuesday
night. By Wednesday a wet and cool weather pattern will take hold
of the region. Showery and cool conditions will continue through
the week, with a drying and warming trend expected this weekend.
Wetter and cooler weather will return early next week.
&&
.DISCUSSION...
Tonight and Tomorrow...Offshore low pressure pushing up against
higher pressure inland has a moist and unstable flow in between.
This is being utilized by smaller mesoscale disturbances and other
triggers to generate both surface and forced elevated showers and
thunderstorms through this interval. HRRR model runs have been
utilized for the short term hours of tonight to time the breaks in
precipitation and allow for the weakening but not really
dissipating north to south oriented band of showers affecting
locations in the lowlands from near Moses Lake and up north to
Republic. Tonight a disturbances rotating around the periphery of
the incoming large scale low will fire off more showers and
thunderstorms and take them in a south to north trajectory with
storm motion near 30 mph or so through Eastern Washington and
North Idaho overnight and into Tomorrow. Number of GFS runs hint
at some of the later convection being highly organized and thus
of longer duration late tonight and into tomorrow which means
there should be a significant amount of rainfall. Thus the
forecast hints at some locations in the North Idaho Panhandle
receiving up to one and one half inches of rainfall in 24
hours...which should increase flow in area rivers and streams. In
addition to the significant rainfall and as is usually the case
gusty wind and small hail is possible near any of these
thunderstorms. /Pelatti
...PERSISTENT BAND OF MODERATE RAIN WEDNESDAY INTO THURSDAY FOR
THE IDAHO PANHANDLE MAY CAUSE LOCALIZED FLOODING...
Wednesday through Friday: The biggest concern for the Wednesday
through Thursday time frame will be the amount of rain that will
fall over the Inland Northwest. A slow moving upper level low will
pivot through northeast Oregon into the Idaho Panhandle and stall
on Thursday into Friday. Deformation band precip (rain wrapping
around the low) should bring a prolonged period of moderate rain
to the Idaho Panhandle, western Montana and southern British
Columbia. We preferred the 00z/12z ECMWF blended the 15z SREF to
build our multi-day precipitation totals. The operational runs of
the NAM and GFS aren`t terribly different with their placement of
the upper low and other mass fields, but these operational models
do become noisy from time to time with convective feedback. The
ensemble SREF and coarser EC suffer from less feedback which will
hopefully lead to a better basin average precipitation forecast.
The highest precipitation totals from early Wednesday morning
through Friday will likely occur over the Idaho Panhandle, namely
Bonner, Boundary and Shoshone counties where as much as 2 to 2.5
inches of rain will be possible through Friday. Areas in far
northeast Washington around Metaline Falls, Newport, and Northport
could get up to 2 inches as well. Rainfall rates don`t appear to
be particularly heavy, but the ECMWF and SREF (which will be
conservative) suggest the heaviest rates will occur Wednesday
morning with as much as a half to three quarters of an inch in 6
hours within a localized band. Most areas should be able to handle
these precipitation rates. The 12z-18z NAM has almost double these
rain rates (up to 1.25 inches per 6 hours) which could cause some
problems on creeks and small streams.
Concern Area #1: The Idaho Panhandle and southeast British
Columbia. A Flood Watch may be necessary for Wednesday for
portions of the Idaho Panhandle for creeks and small streams.
Another concern will be the large amount of precipitation from
Wednesday through Friday over the Kootenai Basin in southeast BC,
NW Montana and far north Idaho. Rises are forecast on the Kootenai
at Bonners Ferry. The potential for more rain next week is not
particularly good news, but it is early to say whether rains next
week will be significant enough to generate run-off.
Concern Area #2: The burn scars in central Washington around
Wenatchee, Chelan and Entiat. Fortunately, the deformation band
with the upper low will be well east of the burn scar area on
Wednesday. There is a small chance on Thursday, that this band
will pivot into central Washington, but it will not likely
maintain precipitation intensity into Thursday. There will also
be a small chance of thunderstorms on Wednesday. The atmosphere
does not appear to be particularly unstable with a 500mb temp of
only -18C to -19C. There should also be a good deal of low
cloudiness Wednesday which should inhibit surface heating
throughout the day. All-in-all, the threat of flash flood appears
to be low over the burn scars through Friday. /GKoch
Friday Night thru Sunday Night... Lingering showers and cool
temperatures will continue over eastern sections of the CWA Friday
night as the persistent upper low slowly moves east from the
southern part of the Idaho Panhandle. Differences in timing
between the EC and GFS cast doubt on how fast the system will move
east on Saturday and while the Cascades and Basin will have mostly
clear skies and warming temperatures, showers may linger over the
Idaho Panhandle. By Saturday night and early Sunday all models
agree that the CWA will be in between systems and under a weak
short wave ridge. The EC then brings in the next system off the
Pacific by Sunday afternoon with an increasing threat for showers
over the Cascades. Precip is on the increase Sunday night as the
ridge moves quickly east and the flows becomes westerly. JL
Monday and Tuesday...It looks like another moist storm system will
be affecting the Inland Northwest next week, bringing increased
rain chances to many areas. There is decent model agreement
regarding this system, with only some slight timing differences.
We went ahead and bumped up precipitation chances, especially
along the Cascade crest. With what is going to fall over the next
couple of days, anything of significance rainfall wise may cause
some hydrology issues. This is definitely something to watch out
for. ty
&&
.AVIATION...
18z TAFS: Moist and unstable air-mass and disturbances passing
through it in a south to north trajectory will keep unsettled
weather such as showers and thunderstorms in the aviation area for
the next 24 hours. VFR should prevail during most of the interval
during non heavy rainfall but near more intense shower and
thunderstorm activity the rainfall could bring ceilings and
visibilities down to MVFR along with gusty wind and small hail.
/Pelatti
&&
.PRELIMINARY POINT TEMPS/POPS...
Spokane 52 54 45 55 44 61 / 80 100 80 80 50 60
Coeur d`Alene 52 54 46 54 42 60 / 90 100 100 90 50 60
Pullman 49 53 44 56 42 60 / 80 100 70 60 30 60
Lewiston 54 58 49 64 44 67 / 70 100 70 60 20 50
Colville 51 63 50 57 48 67 / 90 100 100 100 60 50
Sandpoint 50 56 46 53 45 60 / 100 100 100 100 60 60
Kellogg 50 51 44 51 39 57 / 100 100 100 100 50 60
Moses Lake 55 66 51 65 49 69 / 70 50 50 60 30 30
Wenatchee 56 66 52 64 51 68 / 40 40 50 60 40 30
Omak 53 66 51 64 50 69 / 60 80 70 80 60 50
&&
.OTX WATCHES/WARNINGS/ADVISORIES...
ID...None.
WA...None.
&&
$$
AREA FORECAST DISCUSSION
NWS SPOKANE WA
1048 AM PDT Tue Jun 18 2013
.SYNOPSIS...
Scattered showers and thunderstorms will continue today. By
Wednesday a wet and cool weather pattern will take hold of the
region. Showery and cool conditions will continue through the
week, with a drying and warming trend possible by the weekend.
&&
.DISCUSSION...
Updated zones and grids to show a break in shower and thunderstorm
activity for remainder of morning for extreme Southeast Washington
which includes the Spokane and Coeur D` Alene area relying heavily
on the latest HRRR guidance which suggests such an occurrence
before forced convection redevelops later this afternoon and
evening and moves in via a south to north trajectory of approach
keeping the overnight forecast wet and unsettled. Otherwise
locations further west including the typically drier lowlands of
the Columbia Basin periphery remain wet as forced convection de-
intensifies during the day but does not totally go away and some
surface based convection develops over the mountains to the
north...thus a generally cluttered wet forecast continues.
/Pelatti
&&
.AVIATION...
18z TAFS: Moist and unstable air-mass and disturbances passing
through it in a south to north trajectory will keep unsettled
weather such as showers and thunderstorms in the aviation area for
the next 24 hours. VFR should prevail during most of the interval
during non heavy rainfall but near more intense shower and
thunderstorm activity the rainfall could bring ceilings and
visibilities down to MVFR along with gusty wind and small hail.
/Pelatti
&&
.PRELIMINARY POINT TEMPS/POPS...
Spokane 72 52 54 46 57 46 / 50 80 100 80 70 60
Coeur d`Alene 73 52 56 47 57 45 / 60 90 100 100 90 60
Pullman 74 49 55 44 58 43 / 40 80 100 70 50 60
Lewiston 80 54 61 50 66 49 / 40 70 100 70 50 30
Colville 76 51 63 49 60 46 / 70 90 100 100 80 70
Sandpoint 76 50 58 46 56 44 / 60 100 100 100 90 70
Kellogg 74 50 53 43 53 44 / 70 100 100 100 80 60
Moses Lake 75 55 67 51 65 47 / 30 50 60 40 30 20
Wenatchee 74 56 67 53 62 52 / 40 40 60 50 50 20
Omak 76 53 66 50 62 49 / 50 60 90 70 60 60
&&
.OTX WATCHES/WARNINGS/ADVISORIES...
ID...None.
WA...None.
&&
$$
AREA FORECAST DISCUSSION
NWS SPOKANE WA
802 AM PDT Tue Jun 18 2013
.SYNOPSIS...
Scattered showers and thunderstorms will continue today. By
Wednesday a wet and cool weather pattern will take hold of the
region. Showery and cool conditions will continue through the
week, with a drying and warming trend possible by the weekend.
&&
.DISCUSSION...
Latest HRRR run suggests a decrease, but not total dissipation, of
the elevated convection in the area as the elevated layer upon the
initial forcing is acting upon gets modified/warmed/mixed as
daytime heating occurs. But same model suggests surface based
convection to occur, initially over the mountains to the north
near 18Z and into the early evening while a more robust area of
convection, likely associated with a larger mesoscale shortwave,
grows in intensity and size near 20Z in Eastern Oregon and moves
quickly to the north at near 30 mph or more up into Eastern
Washington and Northern Idaho. It will be very difficult to depict
this scenario with forecast grids and zone forecast wording as
the breaks between the decreasing morning activity and the second
round later in the morning and on through the afternoon/evening is
quite a bit of clutter and the suggested break in activity may not
get articulated all that well, but may get conveyed through
further nowcasts, twitter posts...etc...and any zone updates that
occur may not show much of a change as far as today and tonight
goes. /Pelatti
&&
.AVIATION...
12z TAFS: Low pressure will move over eastern WA and north ID
today and linger through at least the next 48 hours. Scattered
showers with isolated thunderstorms will affect the KGEG/KCOE
corridor this morning while a band of rain will track north over
the KMWH area. The main threat will be periods of heavy rain that
may reduce visibility to MVFR. Another round of convection will
develop late this afternoon and evening which may affect any and
all TAF sites but the main focus will be on northeast WA and the
panhandle of Idaho. /EK
&&
.PRELIMINARY POINT TEMPS/POPS...
Spokane 72 52 54 46 57 46 / 50 80 100 80 70 60
Coeur d`Alene 73 52 56 47 57 45 / 60 90 100 100 90 60
Pullman 74 49 55 44 58 43 / 40 80 100 70 50 60
Lewiston 80 54 61 50 66 49 / 40 70 100 70 50 30
Colville 76 51 63 49 60 46 / 70 90 100 100 80 70
Sandpoint 76 50 58 46 56 44 / 60 100 100 100 90 70
Kellogg 74 50 53 43 53 44 / 70 100 100 100 80 60
Moses Lake 75 55 67 51 65 47 / 80 50 60 40 30 20
Wenatchee 74 56 67 53 62 52 / 60 40 60 50 50 20
Omak 76 53 66 50 62 49 / 70 60 90 70 60 60
&&
.OTX WATCHES/WARNINGS/ADVISORIES...
ID...None.
WA...None.
&&
$$
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
613 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 00Z TAFS THROUGH 00Z THURSDAY EVENING)
ISSUED AT 613 PM CDT WED JUN 19 2013
THE MAIN CONCERN IS WHETHER ANY CONVECTION IS GOING TO IMPACT THE
TAF SITES DURING THE PERIOD. ISOLATED CONVECTION IS DEVELOPING
OVER EASTERN SOUTH DAKOTA AND NEBRASKA AHEAD OF AN APPROACHING
SHORT WAVE TROUGH. AS THE LOW LEVEL JET INTENSIFIES THIS
EVENING...THIS CONVECTION IS EXPECTED TO BECOME MORE WIDESPREAD
AND BEGIN MOVING EAST. THE BEST LOW LEVEL MOISTURE TRANSPORT IS
NOT SHOWN BY THE MODELS TO MOVE EAST WITH THE SHORT WAVE TROUGH
WHICH MAKES IT RATHER UNCLEAR HOW MUCH OF THE CONVECTION WILL
SURVIVE ONCE IT MOVES OUT OF THE MOISTURE FEED AND CAPE AXIS. FOR
THIS REASON...HAVE CONTINUED TO SHOW ONLY SOME VCSH FOR LATE
TONIGHT INTO THURSDAY MORNING. SIMILAR CONCERNS FOR THURSDAY
AFTERNOON AS THE NEXT SHORT WAVE TROUGH STARTS TO APPROACH THE
AREA. BY LATE AFTERNOON...THE 19.18Z NAM SUGGESTS THERE SHOULD BE
BETWEEN 500 AND 1000 J/KG OF ML CAPE OVER THE AREA WITH AN
INCREASE IN MOISTURE TRANSPORT. THE MAIN AREA OF MOISTURE
TRANSPORT WILL BE OFF TO THE WEST...BUT THE EASTERN AND CONVERGENT
EDGE OF THIS MAY BE OVER THE AREA. VARIED IDEAS AS TO WHETHER THE
CONVECTION WILL INITIATE TO THE WEST OF THE AREA...OR NEAR THE
AREA ON A BOUNDARY LEFT BEHIND BY THE MORNING ACTIVITY AS
SUGGESTED BY THE 19.12Z HI-RES NMM. FOR NOW...HAVE OPTED TO
INCLUDED A VCTS FOR THE LATE AFTERNOON TO SHOW THE POSSIBILITY OF
SOME STORMS DEVELOPING.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...DTJ
LONG TERM....DTJ
AVIATION...04
AREA FORECAST DISCUSSION
NWS CHEYENNE WY
914 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 00Z TAFS THROUGH 00Z THURSDAY AFTERNOON)
ISSUED AT 521 PM MDT WED JUN 19 2013
VFR. WINDS GUSTING UP TO 38 KNOTS THROUGH 02Z...THEN DIMINISHING.
AFTER 15Z...WINDS GUSTING UP TO 30 KNOTS. PERIODS OF SCATTERED TO
BROKEN CLOUDS AT OR ABOVE 6000 FEET AGL.
&&
.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 CHEYENNE WY
524 PM MDT WED JUN 19 2013
.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 00Z TAFS THROUGH 00Z THURSDAY AFTERNOON)
ISSUED AT 521 PM MDT WED JUN 19 2013
VFR. WINDS GUSTING UP TO 38 KNOTS THROUGH 02Z...THEN DIMINISHING.
AFTER 15Z...WINDS GUSTING UP TO 30 KNOTS. PERIODS OF SCATTERED TO
BROKEN CLOUDS AT OR ABOVE 6000 FEET AGL.
&&
.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.
&&
$$
SHORT TERM...CLAYCOMB
LONG TERM...HAHN
AVIATION...RUBIN
FIRE WEATHER...CLAYCOMB
AREA FORECAST DISCUSSION
NWS CHEYENNE WY
230 PM MDT TUE JUN 18 2013
.SHORT TERM...(THIS EVENING THROUGH THURSDAY NIGHT)
ISSUED AT 230 PM MDT TUE JUN 18 2013
FORECAST CHALLENGES DEAL WITH SEVERE THUNDERSTORM CHANCES
TODAY...FOLLOWED BY FIRE WEATHER CONCERNS THROUGH FRIDAY. PLEASE
REFER TO FIRE WEATHER SECTION BELOW FOR FIRE WEATHER DETAILS.
CURRENTLY...CONVECTION BEGINNING TO DEVELOP OUT WEST OF THE
LARAMIE RANGE. LATEST WATER VAPOR IMAGERY SHOWING A SUBTLE
SHORTWAVE MOVING INTO SOUTHWESTERN WYOMING THIS AFTERNOON...WHICH
IS MOST LIKELY AIDING IN EARLIER DEVELOPMENT OF TSTMS OUT WEST. A
PRETTY MOIST ATMOSPHERE IN PLACE EAST OF THE LARAMIE RANGE WITH
DEWPOINTS IN THE UPPER 40S JUST EAST OF THE LARAMIE RANGE HERE AT
CHEYENNE. FURTHER EAST IN THE PANHANDLE...LOW TO MID 50 TDS ARE
BEING REPORTED. LATEST SPC MESOANALYSIS SHOWING CAPES OVER EXTREME
SOUTHEASTERN WYOMING AND SOUTHERN PANHANDLE AROUND 600-1000 J/KG
AND CONVECTIVE INHIBITION AT ZERO. STILL CAPPED SOME OVER THE
NORTHERN PANHANDLE AND NIOBRARA COUNTIES WITH ROUGHLY 50-75
J/KG...BUT THIS SHOULD ERODE AWAY AS TEMPERATURES CONTINUE TO
CLIMB THIS AFTERNOON.
THINKING A REPEAT OF YESTERDAY CONVECTION WISE...THOUGH COULD BE MORE
WIDESPREAD WITH THE ASSISTANCE OF THAT LITTLE SHORTWAVE MOVING
THROUGH THE AREA. SEVERE THUNDERSTORMS SHOULD MOVE OFF THE LARAMIE
RANGE INTO THE BETTER ENVIRONMENT TO PRODUCE LARGE HAIL AND
DAMAGING WINDS. SHORTWAVE COMES THROUGH EASTERN WYOMING BY 00Z
THIS AFTERNOON. LATEST HRRR COMPOSITE REFLECTIVITY SHOWING
INDIVIDUAL CELLS DEVELOPING OVER THE LARAMIE RANGE...THEN
CONGEALING INTO A LINE NEAR THE WYOMING/NEBRASKA BORDER AFTER 00Z.
THUNDERSTORMS LOOK TO COME TO AN END MID EVENING AS THE SHORTWAVE
MOVES EAST INTO WESTERN NEBRASKA AFTER 03Z OR SO. UPPER RIDGE AXIS
SHIFTS EAST AS WELL...WITH WEST TO SOUTHWEST WINDS RETURNING TO
CARBON AND ALBANY COUNTIES AFTER MIDNIGHT.
WEDNESDAY LOOKS LIKE A VERY DRY AND WINDY DAY AS 700MB WINDS
INCREASE SIGNIFICANTLY. GFS SHOWING THESE WINDS CLIMBING TO NEAR
40KTS WEST OF THE LARAMIE RANGE. GOOD MID LEVEL WARMING AS WELL
WITH 700MB TEMPERATURES CLIMBING FROM +10C THIS AFTERNOON TO +16C
WEDNESDAY AFTERNOON. LEESIDE TROUGH STILL HANGS OUT OVER THE
PANHANDLE WEDNESDAY AFTERNOON...SO ISOLATED TO WIDELY SCATTERED
THUNDERSTORMS STILL A GOOD BET OUT THAT WAY.
FOR THURSDAY...UPPER LOW CURRENTLY OFF THE WASHINGTON STATE COAST
MOVES INLAND TO THE IDAHO PANHANDLE. THIS WILL KEEP WINDS STRONG
OVER OUR CWFA...BUT 700MB TEMPERATURES COOL SOME...DOWN TO +10 TO
+12C. SO THURSDAY SHOULD BE A LITTLE COOLER OVER WEDNESDAY BY A
FEW DEGREES.
.LONG TERM...(FRIDAY THROUGH TUESDAY)
ISSUED AT 230 PM MDT TUE JUN 18 2013
REX BLOCKING PATTERN ACROSS WESTERN NOAM WILL BREAK DOWN EARLY IN
THE PERIOD AS THE MEANDERING PACNW CLOSED LOW FILLS AND MOVES OUT
ONTO THE NRN ROCKIES/PLAINS. THE DEPTH AT WHICH IT DOES SO WILL
BE THE MAIN FORECAST CHALLENGE AND WILL CARRY RESIDUAL IMPACTS TO
SENSIBLE WEATHER.
ON FRIDAY...UPPER LOW WILL SWING FROM THE IDAHO PANHANDLE INTO
WESTERN MONTANA. 12Z OPERATIONAL GFS AND ECMWF ARE FAIRLY SIMILAR
IN ITS PLACEMENT NR THE ID/MT STATELINE BY EARLY SATURDAY. WEAK
INSTABILITY ACROSS EAST CENTRAL WYOMING AND THE NORTHERN NEBRASKA
PANHANDLE. SO HAVE CONFINED CONVECTIVE CHANCES THERE. THIS LOW
PRESSURE AREA WILL SWING THROUGH MONTANA DURING THE DAY ON
SATURDAY. THE EASTERN PLAINS SHOULD SEE ANOTHER CONVECTIVE DAY ON
SATURDAY AS LLVL MOISTURE DEEPENS AND BACKS UP INTO THE EASTERN
PLAINS. THIS WILL RESULT IN CAPE VALUES THAT WILL ONCE AGAIN CLIMB
ABOVE 2000 J/KG. SATURDAY LOOKS TO PROVIDE THE BEST SEVERE WEATHER
POTENTIAL THROUGH THE PERIOD.
BY SUNDAY AND MONDAY...THE UPPER LOW EJECTS FROM THE DAKOTAS
NORTHEAST TOWARDS HUDSON BAY. THIS SHOULD BRING AN END TO
CONVECTIVE ACTIVITY AND BEGIN TO HEIGHTEN FIRE WEATHER CONCERNS
FOR LATE IN THE WEEKEND/EARLY NEXT WEEK. FLOW WILL BECOME
INCREASINGLY SOUTHWESTERLY AS WELL...WHICH WILL AID IN THE
SURFACING OF GUSTIER WINDS ALOFT.
H7 TEMPERATURES WILL RANGE BETWEEN 13 AND 15C THROUGH THE UPCOMING
WEEKEND AND INCREASE TO 17C BY TUESDAY. HIGH TEMPERATURES WILL
REACH GENERALLY IN THE 80S AND LOW 90S THROUGH THE PERIOD...WITH
EVEN SOME MID AND POTENTIALLY UPPER 90S OUT ON THE FAR EASTERN
PLAINS BY EARLY NEXT WEEK.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY MORNING)
ISSUED AT 1029 AM MDT TUE JUN 18 2013
ANOTHER ROUND OF THUNDERSTORMS THIS AFTERNOON EXPECTED FOR
AIRPORTS FROM KLAR EAST THROUGH THE PANHANDLE. USING THE LATEST
HRRR GUIDANCE...TRIED TO NARROW TIMING OF THUNDERSTORM ONSET.
INITIALLY A FEW CELLS AROUND KLAR AND KCYS...BUT THEN FORMING A
LINE ONCE THE STORMS GET INTO THE PANHANDLE. TIMING LOOKS TO BE
EARLY TO MID AFTERNOON AT KLAR AND KCYS...THEN THE LINE DEVELOPING
AND MOVING THROUGH THE PANHANDLE SHORTLY AFTER 00Z. DO NOT THINK
WE WILL HAVE TO DEAL WITH LOW CEILINGS TONIGHT AS WINDS TURN MORE
DOWNSLOPING OFF THE LARAMIE RANGE TONIGHT.
&&
.FIRE WEATHER...
ISSUED AT 230 PM MDT TUE JUN 18 2013
ELEVATED TO LOCALLY CRITICAL FIRE WEATHER CONDITIONS WEDNESDAY
THROUGH FRIDAY AS HIGH PRESSURE MOVES OFF TO THE EAST AND
SOUTHWEST TO WEST WINDS RETURN TO THE AREA. ZONES ALONG AND WEST
OF THE LARAMIE RANGE LOOK TO SEE WIDESPREAD WINDS OF 20 TO 30 MPH
SUSTAINED WITH GUSTS TO 40 MPH BEGINNING MID MORNING WEDNESDAY
THAT WILL PERSIST THROUGH FRIDAY. WINDIEST TIME PERIODS LOOK TO BE
LATE MORNING THROUGH SUNSET. AFTERNOON HUMIDITIES OUT WEST WILL
FALL TO 5 TO 10 PERCENT WITH POOR OVERNIGHT RECOVERIES WITH THESE
STRONG WINDS. EAST OF THE LARAMIE RANGE...WINDS WILL BE LESS WITH
HIGHER AFTERNOON HUMIDITIES. SINCE ALL ZONES ARE STILL REPORTING
FUELS AS NOT READY FOR RAPID FIRE GROWTH...NO FIRE WEATHER
HEADLINES ARE FORECAST FOR TOMORROW OR FRIDAY AT THIS TIME.
&&
.CYS WATCHES/WARNINGS/ADVISORIES...
WY...NONE.
NE...NONE.
&&
$$
SHORT TERM...CLAYCOMB
LONG TERM...HAHN
AVIATION...CLAYCOMB
FIRE WEATHER...CLAYCOMB
AREA FORECAST DISCUSSION
NWS RIVERTON WY
1126 PM MDT MON JUN 17 2013
.SHORT TERM...TONIGHT THROUGH TUESDAY (ISSUED AT 240 PM)
SHOWERS AND THUNDERSTORMS HAVE BEGUN TO DEVELOP ACROSS THE
MOUNTAINOUS AREAS OF THE FORECAST AREA THIS AFTERNOON. SOME STORMS
HAVE BEGUN TO MOVE INTO THEIR ADJACENT VALLEYS AND BASINS...MAINLY
ACROSS THE UPPER GREEN RIVER BASIN AND JOHNSON COUNTY. ADDITIONAL
STORM ACTIVITY IS ANTICIPATED THROUGH THE AFTERNOON...AND SHOULD
LINGER INTO THE EARLY EVENING HOURS. ACTIVITY WILL WANE WITH THE
LOSS OF DAYLIGHT THIS EVENING...BUT ACTIVITY WILL LINGER OVER THE
CENTRAL AND NORTHERN MOUNTAINS.
ANOTHER...STRONGER DISTURBANCE WILL MOVE OVER THE FORECAST AREA
TUESDAY AFTERNOON. STORMS ARE ANTICIPATED TO START DURING THE EARLY
AFTERNOON HOURS. SOME STORMS WILL SEE THE POTENTIAL TO BECOME
STRONG...ESPECIALLY DURING THE LATER AFTERNOON HOURS. STRONGER
THUNDERSTORMS MAY SEE THE POTENTIAL FOR VERY STRONG WIND GUSTS AND
LARGER HAIL. THESE STRONGER STORMS SEEM MOST FAVORABLE ACROSS
JOHNSON COUNTY...BUT THE EXTENT OF STRONGER STORM COVERAGE MAY NOT
BE REALIZED UNTIL LATE MORNING TUESDAY.
TEMPERATURES WILL WARM ACROSS THE AREA TUESDAY...WITH RELATIVE
HUMIDITY AGAIN DECREASING TO THE SINGLE DIGITS ACROSS SOUTHERN
WYOMING. WIND WILL INCREASE SOMEWHAT DURING THE AFTERNOON...BUT ARE
NOT EXPECTED TO BE SIGNIFICANT ACROSS THE BULK OF THE AREA. THE
EXCEPTION MIGHT BE SOUTHEASTERN SWEETWATER COUNTY.
.LONG TERM...TUESDAY NIGHT THROUGH MONDAY NIGHT
THE THUNDERSTORMS OF TUESDAY AFTERNOON LOOK TO CONTINUE INTO TUESDAY
EVENING BEFORE SLOWLY WANING WITH THE LOSS OF DAYTIME HEATING AND
DRIER AIR PUNCHING IN FROM THE WEST AND SOUTH. MADE FEW CHANGES TO
THE PLACEMENT OF THE STORMS WITH ACTIVITY MAINLY NORTH OF THE WIND
RIVER RANGE...CLOSELY FOLLOWING THE 0.50 PRECIPITABLE WATER LINE.
ON WEDNESDAY ACTIVITY LOOKS TO BE LESS THAN ON TUESDAY WITH MODELS
SHOWING MUCH DRIER AIR IN PLACE ACROSS THE COUNTY WARNING AREA WITH
PRECIPITABLE WATER VALUES FALLING TO UNDER 0.50 FOR ALL AREAS. ANY
CONVECTION WOULD LIKELY BE LIMITED TO NORTHWESTERN WYOMING WHERE
THERE WILL BE A BIT MORE MOISTURE TO WORK WITH AND SOMEWHAT MORE
INSTABILITY DUE TO A CLOSER PROXIMITY TO AN UPPER LEVEL LOW OVER
IDAHO. WITH A COLD FRONT APPROACHING AND MOVING THROUGH...THE
PRESSURE GRADIENT WILL TIGHTEN UP A BIT AND BRING SOME GUSTY WINDS
ACROSS AREAS EAST OF THE DIVIDE...ESPECIALLY ACROSS THE SOUTHWESTERN
WIND CORRIDOR FROM THE RED DESERT THROUGH ROCK SPRINGS. IT DOES NOT
LOOK LIKE HIGH WIND SINCE 700 MILLIBAR WINDS ARE NOT STRONG
ENOUGH...BUT SOME WIND GUSTS TO 40 TO 50 MPH ARE CERTAINLY POSSIBLE.
THERE COULD BE SOME ELEVATED FIRE DANGER IN THE AFTERNOON WITH
RELATIVE HUMIDITY FALLING BELOW 10 PERCENT BUT NO RED FLAGS AT THIS
TIME SINCE FUELS ARE NOT CRITICAL YET. THE DOWNSLOPING WIND WILL
BRING A WARM DAY WITH SOME BASINS SEEING HIGHS AROUND 90. LITTLE
CONVECTION IS EXPECTED EAST OF THE DIVIDE EXCEPT IN THE HIGHER
ELEVATIONS. COOLER AIR WILL ADVECT IN BEHIND THE FRONT FOR WEDNESDAY
NIGHT. IT COULD GET QUITE CHILLY IN THE WESTERN VALLEYS...WITH EVEN
SOME PATCHY FROST IN THE MORE PROTECTED SPOTS.
THURSDAY LOOKS TO BE A COOLER DAY BEHIND THE FRONT WITH LESS WIND AS
WELL. AS FOR ANY CHANCE OF CONVECTION...WE CAN NOT RULE SOMETHING
OUT IN THE FAR NORTHWEST BUT MOISTURE WILL BE LACKING SO FOR WE
TRIMMED POPS A BIT ACROSS NORTHERN WYOMING AND KEPT ANY ACTIVITY
DOWN TO SLIGHT CHANCE. AS A SIDE NOTE...THE SUMMER SOLSTICE IS AT
11:04 PM ON THURSDAY NIGHT SO THAT IS WHEN SUMMER ARRIVES.
AND NOW...TO CELEBRATE THE FIRST FULL DAY OF SUMMER...WE PRESENT THE
DISCUSSION OF FRIDAY WITH THE METEOROLOGICAL VERSION OF THE CLASSIC
OLD SCHOOL RAP SONG SUMMERTIME. SO...DRUMS PLEASE.
HERE IT IS...A PATTERN SLIGHTLY TRANSFORMED
A BIT OF A BREAK FROM THE LATE SPRING NORM
JUST A LITTLE WEATHER TO BREAK THE MONOTONY
OF ALL THE STRONG STORMS THAT HAVE GOTTEN TO BE
A LITTLE BIT OUT OF CONTROL AS THE DAY STARTS OFF COOL
BUT ENDS UP WARM ENOUGH TO GO SWIMMING AT THE POOL
GIVE ME A NICE GENTLE BREEZE
JUST ENOUGH TO RUFFLE THE LEAVES ON THE TREES
AND JUST LIKE THE DAY THAT HAS JUST PAST
IN JOHNSON COUNTY ISOLATED THUNDERSTORMS MAY BLAST
BUT ALL IN ALL AS AFTERNOON TEMPERATURES CLIMB
IT LOOKS NICE FOR THE FIRST DAY OF SUMMERTIME.
IN OTHER WORDS...THE UPPER LEVEL LOW WILL LIFT INTO MONTANA AND LOSE
SOME ITS INFLUENCE OVER THE WEATHER. A BIT MORE MOISTURE MAY HANG
AROUND FAR NORTHERN AND NORTHEASTERN WYOMING BUT ANY CONVECTION
SHOULD BE ISOLATED AT BEST WITH A VAST MAJORITY OF THE AREA RAIN
FREE. SATURDAY LOOKS LIKE A FAIRLY SIMILAR TODAY WITH ISOLATED
CONVECTION ACROSS THE FAR NORTH AND EAST WITH SLIGHTLY DEEPER
MOISTURE BRUSHING BY. TEMPERATURES WILL BE SOMEWHAT ABOVE NORMAL BUT
NOT UNUSUALLY SO. AS FOR SUNDAY AND MONDAY...CONTINUITY INDICATED
MAINLY ISOLATED ACTIVITY ACROSS MORE OF THE AREA WITH SOMEWHAT MORE
MOISTURE SPREADING IN. THE EUROPEAN LOOKS MAINLY DRY WITH THE RIDGE
AXIS OVER THE AREA BUT GIVEN UNCERTAINTY ONLY MINOR CHANGES WERE
MADE.
&&
.AVIATION.../06Z ISSUANCE/
VFR CONDITIONS WILL OCCUR THROUGH 06Z WED. SHOWERS AND THUNDERSTORMS
WILL DEVELOP INITIALLY OVER AND NEAR THE MOUNTAINS AROUND 18Z.
SHOWERS AND STORMS WILL MOVE ACROSS THE LOWER ELEVATIONS DURING THE
AFTERNOON AND EVENING HOURS. THE BEST COVERAGE IS EXPECTED TO BE
OVER THE NORTH OF A LINE FROM KJAC TO KPNA TO KLND TO KCPR. MAINLY
ISOLATED ACTIVITY WILL OCCUR SOUTH OF THIS LINE. WIND GUSTS TO 40
KNOTS ARE LIKELY WITH STORMS. NORTH OF THE LINE MENTIONED ABOVE THE
THREAT FOR BRIEF HEAVY RAIN AND HAIL WILL ALSO OCCUR AND LOCAL MVFR
CONDITIONS IN STORMS. THE STORM ACTIVITY WILL END BY 06Z WED.
&&
.FIRE WEATHER...
SHOWERS AND THUNDERSTORMS ARE EXPECTED ACROSS PORTIONS OF EASTERN
AND NORTHERN WYOMING THROUGH THE EVENING HOURS TONIGHT. ACTIVITY
WILL WEAKEN WITH LOSS OF DAYLIGHT...THOUGH SOME MAY LINGER OVER THE
CENTRAL MOUNTAINS. ANOTHER WARM AND DRY DAY IS EXPECTED ACROSS
SOUTHERN WYOMING ON TUESDAY...WITH HUMIDITY DECREASING INTO THE
SINGLE DIGITS. A SLIGHT INCREASE IN WIND IS ANTICIPATED DURING THE
AFTERNOON...BUT SHOULD NOT BE SIGNIFICANT. HOWEVER...STRONGER
THUNDERSTORMS MAY RETURN TO NORTHEASTERN WYOMING DURING THE
AFTERNOON. THE STRONGEST STORMS MAY HAVE THE POTENTIAL FOR STRONG
ERRATIC WIND AND LARGER HAIL. THE PROMINENT AREAS FOR THIS
DEVELOPMENT ARE JOHNSON AND NATRONA COUNTIES...WITH SOME POTENTIAL
OVER THE BIGHORN BASIN.
&&
.RIW WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
SHORT TERM...BRANHAM
LONG TERM...HATTINGS
AVIATION...AR
FIRE WEATHER...BRANHAM
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 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 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 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 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 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
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 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 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
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
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 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 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 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 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
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 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
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
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 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 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 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 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 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 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 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 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 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 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
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
FORECAST DISCUSSION FOR ROUTINE AFTERNOON FORECAST ISSUANCE
.SYNOPSIS...
ISSUED AT 235 PM CDT THU JUN 20 2013
WARM AND HUMID WITH PLENTY OF RAIN.
WESTERLIES ACRS NOAM SPLIT. WITHIN THE BRANCH OF THE FLOW ACRS THE
CONUS...A FAIRLY DEEP UPR TROF WAS ACRS THE PAC NW...RIDGING
EXTENDED NWD ACRS THE PLAINS...AND A BROAD TROF WAS OVER ERN NOAM.
THE PLAINS RIDGING WL STRENGTHEN AND SHIFT EWD BIT EARLY IN THE
FCST PERIOD. A MORE SUBSTANTIAL CHG IN THE PATTERN IS EXPECTED TO
BEGIN DURING THE LATTER PART OF THE PERIOD...WHEN ALL THE MAIN UPR
FEATURES UNDERGO DISCONTINUOUS RETROGRESSION.
THIS IS A WARM...HUMID...AND RAINY PATTERN...THOUGH THINGS COULD
DRY OUT SOME LATE. PROXIMITY OF UPR RIDGE WL KEEP UPR HEIGHTS VERY
HIGH AND TEMPS ABOVE NORMAL. STREAM OF SHTWVS RIDING ALONG
WESTERLIES ACRS THE AREA AND INTERACTING WITH FRONTAL BOUNDARY
STRUNG OUT ACRS/NEAR THE FCST AREA WL RESULT IN PLENTIFUL
PRECIPITATION...THOUGH TIMING INDIVIDUAL ROUNDS OF PCPN WL BE
DIFFICULT.
&&
.SHORT TERM...TONIGHT AND FRIDAY
ISSUED AT 235 PM CDT THU JUN 20 2013
PROBLEMS TIMING PCPN POP UP RIGHT AT THE START OF THE FCST. LOCAL
MESO GRAPHICS INDICATED 250-750 J/KG MU CAPES ACRS THE AREA...WITH
LITTLE CONVECTIVE INHIBITION. HAD ONE FAIRLY PERSISTENT CLUSTER OF
STORMS AFFECT FAR N-C WI THIS MORNING. CONT TO SEE ADDITIONAL
CELLS DEVELOPING ACRS THE N...CLOSER TO FRONTAL BOUNARY SAGGING
SWD INTO THE AREA. UPR HEIGHTS ARE RISING...SO MAY NOT GET MUCH
MORE SWD MVMT OF THE FRONT. IN ADDITION...SHRTWV WAS APPROACHING
N-C WI FM THE W. SO IT LOOKS LIKE THERE WL BE SOME MECHANISMS TO
CONT FOCUSING CONVECTIVE DEVELOPEMENT OVER NRN WI INTO THE
EVENING. SO...PLACED SOMEWHAT HIGHER POPS THERE. MEANWHILE...ANOTHER
CLUSTER OF SHRA WAS WORKING INTO CENTRAL WI FM THE W. BUT SUPPORT
FOR THESE WL PROBABLY WEAKEN. SO KEEP E-C WI DRY THROUGH THE
EVENING.
MAIN QUESTION IS WHETHER OR NOT MORE ORGANIZED AREA OF STORMS CAN
DEVELOP TO OUR W TNGT...AND MV INTO THE AREA LATE TNGT/FRI
MORNING. SOME OF THE HIGH-RES MODELS REALLY KEYING IN ON STG MCS
DRIVING ESEWD INTO THE FCST AREA AFTER MIDNIGHT. WHILE THAT IS
POSSIBLE...MODELS HAVE BEEN STRUGGLING WITH PCPN PLACEMENT THUS
FAR AND AM SOMEWHAT SKEPTICAL THEY/VE SUDDENLY GOT IT FIGURED
OUT NOW. WL INCR POPS FM W-E LATER TNGT. WL ALSO GO WITH LIKELY
POPS FRI...BUT AT THIS POINT DON/T FEEL COMFORTABLE ADDING AND
REAL SIGNIFICANT TEMPORAL RESOLUTION TO PCPN FCST FOR FRI.
HUMIDITIES WL BE ON THE INCREASE...AND SUSPECT MOST PEOPLE WOULD
JUDGE IT TO BE HUMID BY TOMORROW. TEMPS TOMORROW TRICKY AS THEY WL
DEPEND ON HOW MUCH PCPN IS ARND. EDGED UP A BIT FM PREV FCST...
THOUGH CHG WASN/T REALLY THAT GREAT.
.LONG TERM...FRIDAY NIGHT THROUGH THURSDAY
ISSUED AT 235 PM CDT THU JUN 20 2013
WHILE THE MDLS AGREE ON THE LONG-TERM TREND OF A WRN CONUS UPR
TROF/SE CONUS UPR RDG THRU MON BEFORE TRANSITIONING TO A ROCKIES
UPR RDG/NE CONUS UPR TROF BY NEXT THU...THE DEVIL TO BE IN THE
SMALL-SCALE DETAILS AS TO WHEN TO FIND A BREAK IN THE PCPN CHCS.
THE INITIAL SW FLOW ALOFT WL BRING A WARM/HUMID AIR MASS TO NE WI
WITH A FRONTAL BOUNDARY IN THE VICINITY AND PERIODIC SHORTWAVE
PASSAGES LEADING TO SEVERAL ROUNDS OF SHWRS/TSTMS. INCREASING
INSTABILITY AND SHEAR COULD ALLOW SOME OF THESE STORMS TO TURN
SEVERE...BUT TIMING (WHICH DAY) AT THIS POINT IS VIRTUALLY
IMPOSSIBLE.
MDLS CONT TO SHOW AN INCREASING SW LOW-LEVEL JET FROM THE CNTRL
PLAINS INTO THE MIDWEST FRI NGT AND THIS WL HELP TO LIFT A WRMFNT
TOWARD CNTRL WI DURING THE OVRNGT HOURS. PLENTY OF INSTABILITY AND
MOISTURE TO BE IN PLACE AS THE FRONT APPROACHES PLUS A DIFFLUENT
FLOW ALOFT SHOULD LEAD TO MORE SHWRS/TSTMS ESPECIALLY OVER CNTRL/
E-CNTRL WI. SOME OF THESE STORMS COULD BE STRONG...BUT WITH SHEAR
VALUES A BIT WEAK...ANY SEVERE STORMS APPEAR BETTER FOCUSED TO OUR
WEST.
TRYING TO DETERMINE A BEST LOCATION FOR PCPN CHCS ON SAT TO
ALREADY BE A CHALLENGE DEPENDING ON WHERE EXACTLY THE WRMFNT TO
RESIDE. WL THIS FNT GET BRIEFLY SUPPRESSED SOUTH BY THE EARLIER
TSTMS OR CONT TO TRACK NORTH INTO NRN WI? CURRENT THINKING IS FOR
THE WRMFNT TO STALL OVER CNTRL WI SAT MORNING AND THEN RESUME ITS
NWD TREK SAT AFTERNOON INTO NRN WI. THIS FNT WL CONT TO BE THE
FOCAL POINT FOR ADDITIONAL SHWR/TSTM DEVELOPMENT...THUS MAY HAVE
TO FOCUS HIGHER POPS OVER THE NORTH ONSAT. FIRST TASTE OF TRUE
SUMMER CONDITIONS WITH MAX TEMPS IN THE 80S AND DEW POINTS
FLIRTING WITH 70 DEGS.
THIS WRMFNT IS EXPECTED TO LIFT NWD OUT OF WI ON SAT NGT LEAVING A
WARM/MUGGY AIR MASS OVER NE WI. WL NEED TO AT LEAST CARRY CHC POPS
OVER THE NORTH THRU THE EVENING AS THE WRMFNT DEPARTS...HOWEVER
PCPN CHCS OVER THE REST OF THE FCST AREA ARE SKETCHY AT THE MOMENT
AS BETTER FOCUS FOR STORMS TO BE OVER THE UPR MS VALLEY WHERE A
SHORTWAVE TROF/CDFNT TO COINCIDE. HAVE DECIDED TO LOWER POP CHCS
AT LEAST IN THE EAST FOR NOW AND SEEN IF THIS TREND OF DRIER CONTS
ON THE NEXT MDL RUN. THIS LULL IN THE PCPN MAY LINGER THRU SUNDAY
MORNING BEFORE THE NEXT SHORTWAVE TROF MOVES INTO THE UPR MS
VALLEY AND COMBINES WITH A WEAK CDFNT TO GENERATE THE NEXT ROUND
OF SHWRS/TSTMS. HAVE PLACED HIGHER POPS OM CNTRL/N-CNTRL WI CLOSER
TO THE INCOMING PCPN AND LOWERED POPS A BIT IN THE EAST. IF CLOUDS
CAN HOLD OFF LONG ENUF...WE COULD SEE A FEW LOCATIONS HIT THE 90
DEG MARK...ESPECIALLY IN THE SANDY SOILS FROM WAUTOMA TO KESHENA.
THERE ARE STILL QUESTIONS AS TO WHERE THIS CONVECTIVE COMPLEX WL
MOVE HEADED INTO SUNDAY NGT WITH THE GEM TAKING THE PCPN NE...THE
GFS EAST AND THE ECMWF S-SE. THE 7H MEAN WIND WOULD FAVOR THE
GFS...BUT CANNOT DISCOUNT THE ECMWF AS THE STORMS MAY TRY AND TURN
TOWARD THE BETTER INSTABILITY. WL KEEP CHC POPS PER PREVIOUS
FCST...BUT HEDGE SLIGHTLY HIGHER VALUES OVER CNTRL WI. BY MON...
THE OLD CDFNT WL HAVE STALLED SOMEWHERE OVER CNTRL OR SRN WI AS IT
HITS THE NRN FRINGES OF THE UPR RDG. BEST PCPN CHCS ON MON WL BE
TIED TO THIS FNT...THUS HIGHEST POPS PLACED OVER CNTRL/E-CNTRL WI.
THE NEXT CONVECTIVE COMPLEX MAY DEVELOP OVER THE UPR MS VALLEY MON
NGT AS A 45 KT LOW-LEVEL JET INTERACTS WITH THE STALLED BOUNDARY
OVER SRN MN. THESE STORMS WOULD THEN MOVE E-SE INTO AT LEAST NW WI
TOWARD DAYBREAK. MAY NEED TO ADJUST POPS DOWN OVER MOST OF THE
FCST AREA A MID-LEVEL SUPPORT IS LACKING. THISI COMPLEX WOULD THEN
ROLL EAST AND BRING A CHC OF SHWRS/TSTMS TO NE WI ON TUE. THE
OTHER POINT OF INTEREST ON TUE WL BE THE START OF THE UPR RDG
RETROGRADE AS A MORE PROMINENT SHORTWAVE TROF ENTERS THE PLAINS.
THE TUE NGT INTO WED TIME FRAME COULD BE ACTIVE PERIOD OVER THE
WRN GREAT LAKES AS THE MEAN FLOW CHANGES FROM SW TO NW. THIS
TRANSITION FROM VERY WARM/HUMID TO WARM/LESS HUMID WITH THE
PASSAGE OF THE UPR TROF/CDFNT SHOULD LEAD TO MORE STORMS AND THE
POSSIBILITY OF SEVERE STORMS IF THE SHEAR IS SUFFICIENT. RAIN CHCS
COULD EVEN LINGER INTO NEXT THU AS SEVERAL SHORTWAVES ARE PROGGED
TO DIVE SEWD IN THE NEW NW FLOW ALOFT.
&&
.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 235 PM CDT THU JUN 20 2013
A WARM AND HUMID AIR MASS WILL OVERSPREAD THE COOLER WATERS OF
THE BAY OF GREEN BAY AND LAKE MICHIGAN ON 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 WHICH COULD REDUCE VISIBILITIES BELOW
ONE MILE.
&&
.HYDROLOGY...
ISSUED AT 235 PM 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.
&&
$$
SYNOPSIS.......SKOWRONSKI
SHORT TERM.....SKOWRONSKI
LONG TERM......KALLAS
AVIATION.......SKOWRONSKI
MARINE.........KALLAS
HYDROLOGY......KALLAS
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