Forecast Discussions mentioning any of
"HRRR" "RAP" "RR" "RUC13" "RUC" received at GSD on 07/27/14
AREA FORECAST DISCUSSION
NWS TUCSON AZ
912 AM MST FRI JUL 25 2014
.SYNOPSIS...SHOWERS AND THUNDERSTORMS WILL INCREASE ACROSS THE
AREA TODAY AND CONTINUING INTO THIS WEEKEND WITH THE GREATEST
COVERAGE EXPECTED SATURDAY AFTERNOON AND SATURDAY NIGHT.
TEMPERATURES WILL ALSO FALL BACK CLOSER TO AVERAGE OVER THE NEXT
FEW DAYS.
&&
.DISCUSSION...SURFACE DEW POINTS HAVE GENERALLY BUMPED UP TO THE
MID 60S THIS MORNING DUE TO THE NICE MOISTURE SURGE EARLY THIS
MORNING. THE OUTFLOW THAT BROUGHT THE MOISTURE ALSO BROUGHT A GOOD
AMOUNT OF DUST FROM SONORA UP HERE...WHICH IS THE REASON FOR THE
HAZY CONDITIONS THIS MORNING. THE PREVIOUS SHIFT ADDED HAZE TO THE
GRIDS THRU 18Z...WHICH IS ABOUT THE TIME ALL HIRES GUIDANCE HAS
CONVECTION BEGINNING ACROSS THE FORECAST AREA. HIRES GUIDANCE HAS
MOST STORMS INITIALIZING ACROSS SANTA CRUZ AND COCHISE
COUNTIES...THOUGH THE STORMS OUT EAST AREN`T EXPECTED TO BE MUCH
IN THE WAY OF LONG LIVED DEVELOPMENT. MOST GUIDANCE HAVE THE
WESTERN EDGE OF THE STORMS BEGIN THE DOMINATE FLANK...WHICH WILL
LIKELY RESULT IN A STRONG OUTFLOW/BLOWING DUST TYPE EVENT.
THEREFORE...A BLOWING DUST ADVISORY IS IN PLACE STARTING AT NOON
GIVEN THE EARLY EXPECTED INITIALIZATION. 12Z SOUNDING SHOWS SOME
WEAK MID LEVEL FLOW THOUGH STRONGER FLOW IS PROGGED TO EDGE IN
THIS AFTERNOON.
THE NORTHEASTERN PORTION OF THE CWA AT THIS TIME LOOKS TO BE THE
ONE AREA THAT WON`T RECEIVE MUCH ACTIVITY. THERE ISN`T NEARLY THE
MOISTURE ACROSS GRAHAM OR GREENLEE COUNTIES. HOWEVER...GOES
SOUNDING PROFILES SHOW ENOUGH INSTABILITY FOR SOME WEAK
CONVECTION. NEVERTHELESS...THE MAIN AREA FOR DEVELOPMENT WILL BE
TUCSON TO NOGALES WESTWARD THIS AFTERNOON. IN FACT...MOST GUIDANCE
HAS THINGS ENDING AROUND TUCSON AFTER 3 PM WITH LITTLE TO NO
ACTIVITY EASTWARD. TIME WILL TELL...WILL HOLD THE INHERITED POP
GRIDS.
&&
.AVIATION...VALID THRU 26/12Z.
HIGH PRESSURE CENTERED OVER WEST TEXAS WILL RESULT IN A MOIST ELY/
SELY MID-LEVEL FLOW REGIME INTO SATURDAY MORNING. THE COMBINATION
OF STRONG DAYTIME HEATING COMBINED WITH ADEQUATE MOISTURE WILL
RESULT IN -TSRA/-SHRA MAINLY NEAR THE MOUNTAINS BY 25/19Z FROM
KTUS VICINITY EWD/SWD. SCATTERED TSRA/SHRA IS THEN FORECAST TO
MOVE TO THE WEST AND NORTHWEST THIS AFTERNOON AND THIS EVENING.
AREAS OF BLDU WITH VSBYS BELOW 1/2SM MAY OCCUR NW OF KTUS INTO
PINAL COUNTY SE OF KPHX THIS AFTERNOON AND THIS EVENING.
ELSEWHERE...MVFR VSBYS WITH WIND GUSTS GENERALLY OF 40-45 KTS WILL
OCCUR WITH THE STRONGER TSRA. THERE WILL BE ENOUGH MOISTURE TO
MAINTAIN ISOLATED -TSRA/-SHRA LATE TONIGHT AND EARLY SATURDAY
MORNING. OTHERWISE...CLOUD DECKS THIS AFTERNOON INTO SATURDAY
MORNING WILL GENERALLY BE AT 10-15K FT AGL. AVIATION DISCUSSION
NOT UPDATED FOR TAF AMENDMENTS.
&&
.FIRE WEATHER...AMPLE MOISTURE WILL TRANSLATE INTO SCATTERED
THUNDERSTORMS THIS AFTERNOON AND THIS EVENING. EXPECT SCATTERED TO
NUMEROUS THUNDERSTORMS SATURDAY AFTERNOON AND SATURDAY EVENING AS
MOISTURE INCREASES ACROSS THE AREA. A GRADUAL DECREASE IN
THUNDERSTORM ACTIVITY IS THEN FORECAST TO OCCUR STARTING SUNDAY
AND CONTINUING INTO THE MIDDLE OF NEXT WEEK. HOWEVER...MOISTURE
WILL REMAIN SUFFICIENT FOR ISOLATED TO SCATTERED MAINLY AFTERNOON
AND EVENING THUNDERSTORMS.
&&
.PREV DISCUSSION... /ISSUED 300 AM MST FRI JUL 25 2014/
DISCUSSION...THE ATMOSPHERE HAS MOISTENED UP CONSIDERABLY ACROSS
SOUTHEAST ARIZONA /ESPECIALLY FROM TUCSON WESTWARD/AFTER A GULF
SURGE AIDED BY OUTFLOW FROM THUNDERSTORMS TO OUR SOUTHWEST MOVED
THROUGH THE AREA LAST NIGHT. SURFACE DEWPOINTS ARE GENERALLY IN THE
UPPER 50S TO LOWER 60S ACROSS MOST OF THE AREA WITH THE EXCEPTION OF
GRAHAM AND GREENLEE COUNTY WHERE SURFACE DEWPOINTS ARE MOSTLY IN THE
40S. THIS CORRESPONDS TO PWAT VALUES RANGING FROM UNDER AN INCH IN
GRAHAM AND GREENLEE COUNTY TO 1.2 TO 1.6 INCHES FROM TUCSON
WESTWARD.
THE HIGH PRESSURE ALOFT IS NOW IN A FAVORABLE POSITION ACROSS NEW
MEXICO. GIVEN THE INCREASE IN MOISTURE...AMPLE SUNSHINE TO START THE
DAY AND FAVORABLE EAST TO SOUTHEAST STEERING FLOW...IT IS SHAPING UP
TO BE A FAIRLY ACTIVE DAY ESPECIALLY FROM TUCSON WESTWARD WHERE THE
MOISTURE IS GREATEST. CONFIDENCE IS INCREASING ON SHOWERS AND
THUNDERSTORMS PRODUCING STRONG OUTFLOW WINDS AS REFLECTED IN THE
LATEST HRRR ALONG WITH OUR LOCAL WRF. A BLOWING DUST ADVISORY WILL
BE ISSUED ACROSS PORTIONS OF EASTERN PIMA COUNTY /JUST NORTHWEST OF
TUCSON/ ALONG WITH CENTRAL AND WESTERN PIMA COUNTY AND SOUTH-CENTRAL
PINAL COUNTY TO COVER THE DUST THREAT. STORM MOTION AROUND 10 TO 15
MPH SHOULD BE FAST ENOUGH TO PRECLUDE A WIDESPREAD FLOOD THREAT BUT
LOCALLY HEAVY RAINFALL IS POSSIBLE.
THE ACTIVE PATTERN IS EXPECTED TO CONTINUE ON SATURDAY AS THE
MOISTURE REMAINS ACROSS SOUTHEAST ARIZONA WITH AN INVERTED TROUGH
EXPECTED TO MOVE INTO THE AREA FROM THE EAST SATURDAY EVENING. THIS
SHOULD RESULT IN ADDITIONAL LIFT FOR MORE WIDESPREAD SHOWER AND
THUNDERSTORM ACTIVITY...FOCUSED LATE SATURDAY AFTERNOON INTO
SATURDAY NIGHT. GIVEN THE UPPER LEVEL SUPPORT...THE STORMS MAY VERY
LOSE DIURNAL TRENDS AND CONTINUE IN SOME FASHION OVERNIGHT SATURDAY
NIGHT. IN ADDITION...WE ARE ALSO CONCERNED ABOUT BLOWING DUST ONCE
AGAIN SATURDAY AFTERNOON AND EVENING BUT WE HAVE PLENTY OF TIME TO
HONE IN ON THOSE POSSIBLE DETAILS AS IT GETS CLOSER.
THEREAFTER...SUNDAY MAY VERY WELL BE MORE OF A DOWN DAY WITH
CONSIDERABLE CLOUDS AND A WORKED OVER ATMOSPHERE GIVEN THE EXPECTED
STORM COVERAGE SATURDAY/SATURDAY NIGHT. THE MOISTURE PLUME WILL
REMAIN OVER ARIZONA MONDAY BUT THINGS GET A BIT MORE UNCERTAIN BY
THE MIDDLE OF NEXT WEEK AS THE UPPER HIGH SHIFTS SOUTH AND WEST
CLOSER TO SOUTHEAST ARIZONA. IN FACT...THE 00Z ECMWF SHIFTS THE HIGH
CENTER A BIT SOUTH AND WEST OF US BY WEDNESDAY WITH CONSIDERABLE
DRYING. IN CONTRAST...THE 00Z GFS AND CANADIAN KEEP THE HIGH NEAR
THE AZ/NM BORDER WITH SOMEWHAT BETTER MOISTURE IN THE AREA. MADE
ONLY MINOR TWEAKS TO THE FORECAST FOR NEXT WEEK WITH GENERALLY A
LOWER GRADE MONSOON EXPECTED STARTING TUESDAY. WITH THE HIGH BEING
CLOSER TO THE AREA...TEMPERATURES WILL ALSO BE ON THE INCREASE NEXT
WEEK...RISING TO ABOUT 5 TO 7 DEGREES ABOVE NORMAL VALUES FOR LATE
JULY.
&&
.TWC WATCHES/WARNINGS/ADVISORIES...
BLOWING DUST ADVISORY FROM NOON TODAY TO 9 PM MST THIS EVENING
FOR AZZ501-502-504-505.
&&
$$
PUBLIC...MEADOWS
PREV DISCUSSION...LADER
AVIATION/FIRE WEATHER....FRANCIS
VISIT US ON FACEBOOK...TWITTER...YOUTUBE...AND AT WEATHER.GOV/TUCSON
AREA FORECAST DISCUSSION
NWS TUCSON AZ
300 AM MST FRI JUL 25 2014
.SYNOPSIS...SHOWERS AND THUNDERSTORMS WILL INCREASE ACROSS THE AREA
TODAY AND CONTINUING INTO THIS WEEKEND WITH THE GREATEST COVERAGE
EXPECTED SATURDAY AFTERNOON AND SATURDAY NIGHT. TEMPERATURES WILL
ALSO FALL BACK CLOSER TO AVERAGE OVER THE NEXT FEW DAYS.
&&
.DISCUSSION...THE ATMOSPHERE HAS MOISTENED UP CONSIDERABLY ACROSS
SOUTHEAST ARIZONA /ESPECIALLY FROM TUCSON WESTWARD/AFTER A GULF
SURGE AIDED BY OUTFLOW FROM THUNDERSTORMS TO OUR SOUTHWEST MOVED
THROUGH THE AREA LAST NIGHT. SURFACE DEWPOINTS ARE GENERALLY IN THE
UPPER 50S TO LOWER 60S ACROSS MOST OF THE AREA WITH THE EXCEPTION OF
GRAHAM AND GREENLEE COUNTY WHERE SURFACE DEWPOINTS ARE MOSTLY IN THE
40S. THIS CORRESPONDS TO PWAT VALUES RANGING FROM UNDER AN INCH IN
GRAHAM AND GREENLEE COUNTY TO 1.2 TO 1.6 INCHES FROM TUCSON
WESTWARD.
THE HIGH PRESSURE ALOFT IS NOW IN A FAVORABLE POSITION ACROSS NEW
MEXICO. GIVEN THE INCREASE IN MOISTURE...AMPLE SUNSHINE TO START THE
DAY AND FAVORABLE EAST TO SOUTHEAST STEERING FLOW...IT IS SHAPING UP
TO BE A FAIRLY ACTIVE DAY ESPECIALLY FROM TUCSON WESTWARD WHERE THE
MOISTURE IS GREATEST. CONFIDENCE IS INCREASING ON SHOWERS AND
THUNDERSTORMS PRODUCING STRONG OUTFLOW WINDS AS REFLECTED IN THE
LATEST HRRR ALONG WITH OUR LOCAL WRF. A BLOWING DUST ADVISORY WILL
BE ISSUED ACROSS PORTIONS OF EASTERN PIMA COUNTY /JUST NORTHWEST OF
TUCSON/ ALONG WITH CENTRAL AND WESTERN PIMA COUNTY AND SOUTH-CENTRAL
PINAL COUNTY TO COVER THE DUST THREAT. STORM MOTION AROUND 10 TO 15
MPH SHOULD BE FAST ENOUGH TO PRECLUDE A WIDESPREAD FLOOD THREAT BUT
LOCALLY HEAVY RAINFALL IS POSSIBLE.
THE ACTIVE PATTERN IS EXPECTED TO CONTINUE ON SATURDAY AS THE
MOISTURE REMAINS ACROSS SOUTHEAST ARIZONA WITH AN INVERTED TROUGH
EXPECTED TO MOVE INTO THE AREA FROM THE EAST SATURDAY EVENING. THIS
SHOULD RESULT IN ADDITIONAL LIFT FOR MORE WIDESPREAD SHOWER AND
THUNDERSTORM ACTIVITY...FOCUSED LATE SATURDAY AFTERNOON INTO
SATURDAY NIGHT. GIVEN THE UPPER LEVEL SUPPORT...THE STORMS MAY VERY
LOSE DIURNAL TRENDS AND CONTINUE IN SOME FASHION OVERNIGHT SATURDAY
NIGHT. IN ADDITION...WE ARE ALSO CONCERNED ABOUT BLOWING DUST ONCE
AGAIN SATURDAY AFTERNOON AND EVENING BUT WE HAVE PLENTY OF TIME TO
HONE IN ON THOSE POSSIBLE DETAILS AS IT GETS CLOSER.
THEREAFTER...SUNDAY MAY VERY WELL BE MORE OF A DOWN DAY WITH
CONSIDERABLE CLOUDS AND A WORKED OVER ATMOSPHERE GIVEN THE EXPECTED
STORM COVERAGE SATURDAY/SATURDAY NIGHT. THE MOISTURE PLUME WILL
REMAIN OVER ARIZONA MONDAY BUT THINGS GET A BIT MORE UNCERTAIN BY
THE MIDDLE OF NEXT WEEK AS THE UPPER HIGH SHIFTS SOUTH AND WEST
CLOSER TO SOUTHEAST ARIZONA. IN FACT...THE 00Z ECMWF SHIFTS THE HIGH
CENTER A BIT SOUTH AND WEST OF US BY WEDNESDAY WITH CONSIDERABLE
DRYING. IN CONTRAST...THE 00Z GFS AND CANADIAN KEEP THE HIGH NEAR
THE AZ/NM BORDER WITH SOMEWHAT BETTER MOISTURE IN THE AREA. MADE
ONLY MINOR TWEAKS TO THE FORECAST FOR NEXT WEEK WITH GENERALLY A
LOWER GRADE MONSOON EXPECTED STARTING TUESDAY. WITH THE HIGH BEING
CLOSER TO THE AREA...TEMPERATURES WILL ALSO BE ON THE INCREASE NEXT
WEEK...RISING TO ABOUT 5 TO 7 DEGREES ABOVE NORMAL VALUES FOR LATE
JULY.
&&
.AVIATION...VALID THRU 26/12Z.
HIGH PRESSURE CENTERED OVER WEST TEXAS WILL RESULT IN A MOIST ELY/
SELY MID-LEVEL FLOW REGIME INTO SATURDAY MORNING. THE COMBINATION OF
STRONG DAYTIME HEATING COMBINED WITH ADEQUATE MOISTURE WILL RESULT
IN -TSRA/-SHRA MAINLY NEAR THE MOUNTAINS BY 25/19Z FROM KTUS
VICINITY EWD/SWD. SCATTERED TSRA/SHRA IS THEN FORECAST TO MOVE TO
THE WEST AND NORTHWEST THIS AFTERNOON AND THIS EVENING. AREAS OF
BLDU WITH VSBYS BELOW 1/2SM MAY OCCUR NW OF KTUS INTO PINAL COUNTY
SE OF KPHX THIS AFTERNOON AND THIS EVENING. ELSEWHERE...MVFR VSBYS
WITH WIND GUSTS GENERALLY OF 40-45 KTS WILL OCCUR WITH THE STRONGER
TSRA. THERE WILL BE ENOUGH MOISTURE TO MAINTAIN ISOLATED -TSRA/-SHRA
LATE TONIGHT AND EARLY SATURDAY MORNING. OTHERWISE...CLOUD DECKS
THIS AFTERNOON INTO SATURDAY MORNING WILL GENERALLY BE AT 10-15K FT
AGL. AVIATION DISCUSSION NOT UPDATED FOR TAF AMENDMENTS.
&&
.FIRE WEATHER...AMPLE MOISTURE WILL TRANSLATE INTO SCATTERED
THUNDERSTORMS THIS AFTERNOON AND THIS EVENING. EXPECT SCATTERED TO
NUMEROUS THUNDERSTORMS SATURDAY AFTERNOON AND SATURDAY EVENING AS
MOISTURE INCREASES ACROSS THE AREA. A GRADUAL DECREASE IN
THUNDERSTORM ACTIVITY IS THEN FORECAST TO OCCUR STARTING SUNDAY AND
CONTINUING INTO THE MIDDLE OF NEXT WEEK. HOWEVER...MOISTURE WILL
REMAIN SUFFICIENT FOR ISOLATED TO SCATTERED MAINLY AFTERNOON AND
EVENING THUNDERSTORMS.
&&
.TWC WATCHES/WARNINGS/ADVISORIES...
BLOWING DUST ADVISORY FROM 2 PM THIS AFTERNOON TO 9 PM THIS EVENING
FOR AZZ501-502-504-505.
&&
$$
VISIT US ON FACEBOOK...TWITTER...YOUTUBE...AND AT WEATHER.GOV/TUCSON
SOUTHWEST CALIFORNIA AREA FORECAST DISCUSSION
NWS LOS ANGELES/OXNARD CA
223 PM PDT FRI JUL 25 2014
.SYNOPSIS...
HIGH PRESSURE WILL REMAIN ANCHORED OVER THE DESERT SOUTHWEST THROUGH
THE MIDDLE OF NEXT WEEK RESULTING IN CONTINUED SEASONAL TO ABOVE
NORMAL TEMPERATURES. HIGH CLOUDS WILL STREAM THROUGH THE AREA WITH A
SLIGHT POSSIBILITY OF A THUNDERSTORM OVER THE SAN GABRIELS MAINLY
SUNDAY AFTERNOON. OVERNIGHT LOW CLOUDS AND FOG ARE EXPECTED ALONG
MOST COASTAL AREAS.
&&
.SHORT TERM (REST OF TODAY-MON)...STILL KEEPING AN EYE ON THE LINE
OF THICKER CLOUDS AND ISOLATED CONVECTION INCHING NORTHWARD ON A
LINE FROM JUST NORTH OF LAS VEGAS SOUTHWESTWARD TOWARD JUST SOUTH OF
CATALINA AT THIS TIME. MOST ACTIVE CONVECTION IS IN THE PALM SPRINGS
AREA...OTHERWISE KSOX INDICATING ECHOES OFFSHORE JUST SOUTH OF
CATALINA...ALTHOUGH ONLY WELL ALOFT AT THIS TIME. THIS ACTIVITY IS
IN PART DUE TO A WEAK WAVE APPARENT IN THE FLOW AROUND THE LARGE
HIGH STILL CENTERED OVER THE SOUTHERN HIGH PLAINS. THE RUC MODEL
(PER 400 MB VORT) SORT OF WASHES THIS OUT WITH TIME THIS
EVENING...THOUGH STILL APPARENT. LATEST LIFTED INDEX VALUES STILL
REMAIN LOWEST EAST OF OUR AREA WITH JUST BELOW ZERO VALUES INTO OUR
AREA...BUT FORECAST TO STABILIZE AFTER 21Z. VISIBLE SATELLITE
IMAGERY AND DOWNTOWN LA WEBCAMS SHOW CU TRYING TO BUILD ON THE
NORTHERN EDGE OF THE EASTERN SAN GABRIELS...BUT UPDRAFTS LOOK WEAK
AND DISORGANIZED SO FAR. LATEST HIGH RESOLUTION RAPID REFRESH (HRRR)
MODEL RUN FROM 19Z ALSO KEEPS PRECIPITATION OUT OF OUR AREA. FOR
NOW BELIEVE NOTHING OF SIGNIFICANCE WILL MATERIALIZE FROM THIS OTHER
THAN SOME INCREASING MID AND HIGH CLOUDINESS ACROSS LOS ANGELES AND
PARTS OF VENTURA COUNTIES....BUT WILL CONTINUE TO MONITOR. MAY NEED
TO AT LEAST INCREASE THE FORECAST SKY COVER FOR THIS EVENING OVER
THESE AREAS.
BEYOND THE REST OF THIS AFTERNOON AND EVENING...THE PRIMARY FACTOR
IN THE FORECAST IS THE PERSISTENT HIGH PRESSURE SYSTEM OVER THE
WESTERN U.S. WHICH WILL VARY IN AXIS POSITION AND SHAPE OVER THE
NEXT 7 DAYS. THE RESULT WILL MEAN LITTLE CHANGE IN THE DAY TO DAY
CONDITIONS. AFTERNOON TEMPERATURES WILL CHANGE LITTLE EACH
DAY...REMAINING FROM JUST ABOVE NORMAL VALLEYS AND INLAND...BUT WITH
SOME ONSHORE FLOW THROUGH THE PERIOD...THE COASTAL AREAS WILL REMAIN
AT OR JUST BELOW NORMAL.
EXPECT A SLIGHT INCREASE IN COVERAGE ALONG THE COASTS OF THE
OVERNIGHT CLOUDS AND FOG TONIGHT...AND A REPEAT PERFORMANCE ON
SUNDAY AND MONDAY. WITH THE ONSHORE FLOW COMES GUSTY SOUTHWEST WINDS
EACH AFTERNOON IN THE ANTELOPE VALLEY...BUT STAYING BELOW ADVISORY
CRITERIA.
THE ONE HICCUP IN THE PERSISTENCE FORECAST MAY BE SUNDAY AFTERNOON
AND EVENING IN THE LA AND VTU COUNTY MOUNTAINS AND THE ANTELOPE
VALLEY. SOME INDICATIONS OF SOME CONVECTIVE ACTIVITY THESE AREAS
SUNDAY AFTERNOON. CONVECTIVE PARAMETERS NOT OVERLY IMPRESSIVE OTHER
THAN MODELS INDICATING A POSSIBLE SHORT WAVE THAT ROTATES AROUND THE
SOUTH SIDE OF THE HIGH THEN ROTATES AROUND AND BRUSHES OUR AREA ON
SUNDAY. THIS WILL COME INTO BETTER FOCUS WITH NEW MODEL RUNS BUT
HAVE KEPT THE GOING FORECAST OF A SLIGHT CHANCE OF THUNDER OVER THE
EASTERN SAN GABRIELS FOR NOW.
.LONG TERM (TUE-FRI)...THE UPPER LEVEL HIGH OVER THE WESTERN U.S.
PERSISTS THROUGH THE LONG TERM. THE ONE CHANGE IS THAT IT PUMPS UP
INTO SOUTHWEST CANADA AS OPPOSED TO THE EAST-WEST ELONGATED HIGH
THAT IT`S BEEN AS OF LATE. THE ECMWF PUTS THE HIGH AXIS A LITTLE
FURTHER WEST...THE RESULT BEING AROUND A 585 DM THICKNESS OVER SOCAL
ON WEDN AFTN VERSUS THE 579 DM THICKNESS FORECAST BY THE GFS. THIS
WOULD RESULT IN WARMER TEMPS MIDWEEK. DISCOUNTING THE ECMWF FOR NOW
IN PART SINCE THE OPERATIONAL GFS IS IN LINE WITH THE GFS ENSEMBLES.
SO GOING WITH THE GFS...NOT MUCH CHANGE IN SENSIBLE SURFACE WEATHER
FROM DAY TO DAY. TEMPERATURES JUST ABOVE AVERAGE VALLEYS AND DESERT
AND AT OR JUST BELOW AVERAGE COASTAL AREAS. ONSHORE GRADIENTS WILL
CHANGE LITTLE EACH DAY SO EXPECT SOME OVERNIGHT LOW CLOUDS AND FOG
ALONG THE COASTS...BUT AT THIS TIME WITH NOT MUCH INLAND EXTENT. WE
APPEAR TO BE RIGHT ON THE WESTERN EDGE OF ANY MONSOONAL FLOW SO
DIFFICULT TO TELL AT THIS POINT WHEN WE MAY GET ENOUGH MOISTURE THIS
FAR WEST FOR ANY CONVECTIVE ACTIVITY. AT THIS TIME HAVE NOT INCLUDED
ANY MENTION OF IT DURING THIS PERIOD.
&&
.AVIATION...25/18Z...
MODERATE TO HIGH CONFIDENCE IN THE 18Z TAFS. SLOW CLEARING IN SOME
COASTAL LOCATIONS THOUGH VFR CONDITIONS ARE IN PLACE THROUGHOUT THE
SERVICE AREA. THE MARINE LAYER IS EXPECTED TO RETURN TO ALL COASTAL
SITES OVERNIGHT IN A SIMILAR PATTERN AS THIS MORNING THOUGH FOR A
SLIGHTLY LONGER DURATION. OTHERWISE AND ELSEWHERE VFR CONDITIONS
ARE EXPECTED.
KLAX...MODERATE CONFIDENCE IN THE 18Z TAF. THE MARINE LAYER IS
EXPECTED TO RETURN OVERNIGHT IN A SIMILAR PATTERN AS THIS MORNING
THOUGH FOR A SLIGHTLY LONGER DURATION. THERE IS A 20 PERCENT CHANCE
THAT CIGS WILL SLIP INTO THE IFR CATEGORY FOR ONE TO THREE HOURS
THROUGH 16Z... A 10 TO 20 PERCENT CHANCE THAT CIGS WILL LINGER UNTIL
AS LATE AS 19Z... AND A 20 PERCENT CHANCE THAT EAST WINDS WILL REACH
OR EXCEED 9 KNOTS BETWEEN 13Z AND 16Z. OTHERWISE VFR CONDITIONS ARE
EXPECTED.
KBUR...HIGH CONFIDENCE IN THE 18Z TAF. VFR CONDITIONS EXPECTED
THROUGHOUT THE FORECAST PERIOD.
&&
.MARINE...25/230 PM...
HIGH CONFIDENCE IN CURRENT FORECAST. WINDS AND SEAS ARE CONTINUING
TO DECREASE THOUGH SOME SENSORS INDICATE LOCAL SEA HEIGHTS ARE A BIT
SLOWER TO DECREASE THAN EARLIER EXPECTED... POSSIBLY DUE TO A SMALL
BUMP IN THE WIND WAVES. THEREFORE THE SMALL CRAFT ADVISORY FOR
HAZARDOUS SEAS HAS BEEN EXTENDED INTO THE EVENING HOURS. OTHERWISE
CONDITIONS ARE EXPECTED TO REMAIN BELOW ADVISORY CRITERIA THROUGH
THE REMAINDER OR THE FORECAST PERIOD.
REPORTS OF MOSTLY DRY LIGHTNING TO THE SOUTH AND EAST OF THE
FORECAST AREA TODAY AND ANY FURTHER THUNDERSTORM DEVELOPMENT IS
EXPECTED TO REMAIN OUT OF THE AREA THROUGH TONIGHT. THE BOUNDARY
UPON WHICH THE CONVECTION IS DEVELOPING WILL BE SHIFTING
NORTHWESTWARD THROUGH SUNDAY... HOWEVER... AND MAY MOVE INTO ZONES
676 AND 655 BY SUNDAY.
&&
.LOX WATCHES/WARNINGS/ADVISORIES...
SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS (SEE LAXMWWLOX).
&&
$$
PUBLIC...MJ
AVIATION...KJ
MARINE...KJ
SYNOPSIS...MJ
WWW.WEATHER.GOV/LOSANGELES
AREA FORECAST DISCUSSION
NWS DENVER/BOULDER CO
1112 AM MDT FRI JUL 25 2014
.UPDATE...
ISSUED AT 1050 AM MDT FRI JUL 25 2014
MOST OF THE PLAINS SHOW NORTHEASTERLY FLOW LEVEL WINDS RIGHT NOW.
THERE IS PLENTY OF MID AND UPPER LEVEL CLOUDS AROUND. THE
CONVECTIVE CLOUDINESS HAS STARTED IN THE MOUNTAINS AND FOOTHILLS
BUT THERE ARE VERY FEW ECHOES ON THE RADAR. WE ARE ONE DEGREE F
COOLER AT DIA RIGHT NOW THAN WE WERE YESTERDAY. THE LATEST DIA
ACARS SOUNDINGS ARE SHOWING A STABLE LAYER AROUND 15000 FEET MST.
THE PLAINS HAVE DEW POINTS MOSTLY IN THE LOWER 50S F RIGHT
NOW...A FEW PLACES A BIT LOWER. MODELS CONTINUE TO SHOW SOME AREAS
OF 1000 J/KG PLUS CAPES THIS AFTERNOON OVER SOME OF THE CWA. WILL
KEEP THE GOING POPS PRETTY MUCH ALONE FOR NOW. WILL UP
TEMPERATURES A BIT AND MAKE A FEW MINOR CLOUD COVER ALTERATIONS.
&&
.SHORT TERM...(TODAY THROUGH TONIGHT )
ISSUED AT 330 AM MDT FRI JUL 25 2014
THE UPPER HIGH HAS SHIFTED SOUTH OF COLORADO DURING THE PAST 12
HOURS AND IS NOW CENTERED OVER NEW MEXICO AND WESTERN TEXAS. THIS
HAS RESULTED IN A MORE WESTERLY FLOW ALOFT OVER COLORADO WITH MAIN
MOISTURE PLUME ACROSS NORTHERN AND CENTRAL PORTIONS OF THE STATE.
INTEGRATED PRECIPITABLE WATER VALUES ARE JUST UNDER AN INCH OVER
FRONT RANGE. EXPECT THIS PLUME OF MOISTURE TO HOLD OVER THE REGION
FOR THIS AFTERNOON AND TONIGHT WITH PW VALUES REMAINING CLOSE TO
AN INCH. THERE ARE STILL ISOLATED SHOWERS AND THUNDERSTORMS
CONTINUING OVER MOUNTAINS AND WEST AND HAVE ADDED LOW POPS FOR THE
PRE DAWN HOURS.
A WEAK COLD FRONT WILL MOVE SOUTH FROM WYOMING DURING THE EARLY
MORNING HOURS OVER NORTHEAST COLORADO WITH NORTHEAST TO EAST WINDS
DEVELOPING BEHIND THE FRONT. THERE WILL BE SOME COOLING AND LOW
LEVEL STABILITY THIS AFTERNOON BUT LOW LEVEL CAP LOOKS TO ERODE BY
LATE AFTERNOON WHILE SURFACE DEWPOINTS REMAIN IN THE UPPER 40S AND
LOWER 50S. SHOULD BE ENOUGH INSTABILITY AND AMPLE MOISTURE FOR A
ROUND OF SHOWERS AND THUNDERSTORMS THIS AFTERNOON. LATEST HRRR
SHOWING A BROAD AREA OF SHOWERS MOVING OFF THE FOOTHILLS BETWEEN
20-22Z. THE RAP/NAM SEEM TO HOLD MORE OF THE SHOWERS ANCHORED ON
HIGHER TERRAIN WITH MORE ISOLATED ACTIVITY ON THE PLAINS. GIVEN
THE AMOUNT OF MOISTURE WOULD FAVOR THE HRRR SOLUTION AND WILL BUMP
POPS UP SLIGHTLY TO CHANCE CATEGORIES BY LATE AFTERNOON OVER THE
FRONT RANGE AND ADJACENT PLAINS. LIKE YESTERDAY...MAIN THREATS
WILL BE BRIEF HEAVY RAIN AND GUSTY WINDS TO AROUND 50 MPH WITH THE
STRONGER STORMS.
TEMPERATURES WILL BE COOLER TODAY FOLLOWING THE
FRONTAL PASSAGE WITH READINGS AROUND 90 DEGREES OVER LOWER
ELEVATIONS. MOST OF THE STORMS WILL DIMINISH BY LATER THIS EVENING
WITH LACK OF ANY SIGNIFICANT FORCING ALOFT.
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 330 AM MDT FRI JUL 25 2014
ANOTHER WEAK BACKDOOR COLD FRONT IS EXPECTED TO PUSH ACROSS THE
PLAINS ON SATURDAY...RESULTING IN SLIGHT COOLING AND
STABILIZATION. THE AIRMASS WILL LIKELY REMAIN CAPPED OVER THE
NORTHEAST CORNER OF THE STATE...WHILE THE MOUNTAINS WILL STILL SEE
SCATTERED SHOWERS AND STORMS IN THE AFTERNOON AND EVENING AS
MID/UPPER LEVEL MOISTURE PLUME REMAINS ACROSS THE FORECAST AREA.
IN BETWEEN...THE ENVIRONMENT WILL BE MARGINAL FOR STORMS...BUT
WITH WESTERLY FLOW ALOFT WE SHOULD SEE ISOLATED SHOWERS/STORMS DRIFT
OFF THE FRONT RANGE AND HELP POP A FEW CELLS THROUGH THE CAP.
ON SUNDAY...TEMPERATURES WILL TREND A GOOD 5-10 DEGREES COOLER
ACROSS THE PLAINS BEHIND A DEEPENING POOL OF COOL AIR. THERE WILL
BE A THETA-E MINIMUM AND SLIGHT DRYING ACROSS MOST OF THE PLAINS
AS WELL...WHICH SHOULD EFFECTIVELY CUT OFF THE NORTHEAST PLAINS
FROM CONVECTION. MEANWHILE...MOUNTAIN AREAS WILL SEE ENOUGH
INSTABILITY FOR ANOTHER ROUND OF SCATTERED SHOWERS AND
STORMS...WITH A FEW POSSIBLY DRIFTING OFF THE FOOTHILLS INTO THE
I-25 CORRIDOR ONCE AGAIN BY LATE AFTERNOON/EVENING. AT THIS
TIME...LOOKS LIKE MAIN THREAT WOULD BE CLOSER TO THE PALMER DIVIDE
AREA HOWEVER AS AIRMASS FARTHER NORTH IS DRYING.
BY MONDAY...LOW LEVEL MOISTURE BEGINS TO RETURN AND INCREASE IN
SOUTH/SOUTHEAST FLOW. MEANWHILE...THETA-E RIDGE BUILDS IN/NEAR THE
FRONT RANGE WITH CAPES INCREASING TO AROUND 1500 J/KG. THIS ALONG
WITH SUFFICIENT SHEAR IN NORTHWEST FLOW ALOFT COULD LEAD TO A FEW
SEVERE STORMS.
ON TUESDAY...LOW LEVEL MOISTURE WILL LIKELY CONTINUE TO POOL ALONG
THE FRONT RANGE WHILE A SHORT WAVE IS STILL BEING ADVERTISED TO
DROP ACROSS THE REGION IN NORTHWEST FLOW ALOFT. THE UPSLOPE
COMPONENT IS ALSO PROGGED BY VARIOUS MODELS TO DEEPEN THROUGH 700
MB...COLLECTIVELY RESULTING IN A GOOD CHANCE OF SHOWERS AND
THUNDERSTORMS. CAPE MAY BE LIMITED BY COOLER TEMPERATURES...BUT
HIGH PRECIPITABLE WATER VALUES AND LIKELY SKINNY CAPE PROFILE
SUGGESTS POTENTIAL FOR HEAVY RAINFALL.
WEDNESDAY AND THURSDAY WILL FEATURE A CONTINUATION OF A COOL AND
SOMEWHAT UNSETTLED WEATHER PATTERN. BEST CHANCE SHOULD REFOCUS TO
THE ELEVATED TERRAIN THOUGH AS AIRMASS ON THE PLAINS WOULD BE MORE
STABLE BEHIND TUESDAYS WAVE AND WITH COOLER TEMPERATURES HOLDING
IN PLACE. PLAINS LOCATIONS MAY STRUGGLE TO REACH 80F BOTH DAYS.
&&
.AVIATION...(FOR THE TAFS THROUGH 18Z SATURDAY MORNING)
ISSUED AT 1050 AM MDT FRI JUL 25 2014
WINDS ARE A BIT TROUBLESOME AT DIA RIGHT. THERE IS A PRETTY
UNIFORM NORTHEASTERLY WIND FIELD OVER MOST OF THE PLAINS RIGHT
NOW...EXCEPT FOR THE BIG AIRPORT. THE RADAR POINTS TO
NORTHEASTERLIES AT DIA EVENTUALLY. THERE WILL BE NO CEILING
ISSUES THIS AFTERNOON. WINDS GUSTS ASSOCIATED WITH CONVECTION
COULD BE AN ISSUE THIS AFTERNOON/EARLY EVENING.
&&
.BOU WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...RJK
SHORT TERM...ENTREKIN
LONG TERM...BARJENBRUCH
AVIATION...RJK
AREA FORECAST DISCUSSION
NWS DENVER/BOULDER CO
328 AM MDT FRI JUL 25 2014
.SHORT TERM...(TODAY THROUGH TONIGHT )
ISSUED AT 330 AM MDT FRI JUL 25 2014
THE UPPER HIGH HAS SHIFTED SOUTH OF COLORADO DURING THE PAST 12
HOURS AND IS NOW CENTERED OVER NEW MEXICO AND WESTERN TEXAS. THIS
HAS RESULTED IN A MORE WESTERLY FLOW ALOFT OVER COLORADO WITH MAIN
MOISTURE PLUME ACROSS NORTHERN AND CENTRAL PORTIONS OF THE STATE.
INTEGRATED PRECIPITABLE WATER VALUES ARE JUST UNDER AN INCH OVER
FRONT RANGE. EXPECT THIS PLUME OF MOISTURE TO HOLD OVER THE REGION
FOR THIS AFTERNOON AND TONIGHT WITH PW VALUES REMAINING CLOSE TO
AN INCH. THERE ARE STILL ISOLATED SHOWERS AND THUNDERSTORMS
CONTINUING OVER MOUNTAINS AND WEST AND HAVE ADDED LOW POPS FOR THE
PRE DAWN HOURS.
A WEAK COLD FRONT WILL MOVE SOUTH FROM WYOMING DURING THE EARLY
MORNING HOURS OVER NORTHEAST COLORADO WITH NORTHEAST TO EAST WINDS
DEVELOPING BEHIND THE FRONT. THERE WILL BE SOME COOLING AND LOW
LEVEL STABILITY THIS AFTERNOON BUT LOW LEVEL CAP LOOKS TO ERODE BY
LATE AFTERNOON WHILE SURFACE DEWPOINTS REMAIN IN THE UPPER 40S AND
LOWER 50S. SHOULD BE ENOUGH INSTABILITY AND AMPLE MOISTURE FOR A
ROUND OF SHOWERS AND THUNDERSTORMS THIS AFTERNOON. LATEST HRRR
SHOWING A BROAD AREA OF SHOWERS MOVING OFF THE FOOTHILLS BETWEEN
20-22Z. THE RAP/NAM SEEM TO HOLD MORE OF THE SHOWERS ANCHORED ON
HIGHER TERRAIN WITH MORE ISOLATED ACTIVITY ON THE PLAINS. GIVEN
THE AMOUNT OF MOISTURE WOULD FAVOR THE HRRR SOLUTION AND WILL BUMP
POPS UP SLIGHTLY TO CHANCE CATEGORIES BY LATE AFTERNOON OVER THE
FRONT RANGE AND ADJACENT PLAINS. LIKE YESTERDAY...MAIN THREATS
WILL BE BRIEF HEAVY RAIN AND GUSTY WINDS TO AROUND 50 MPH WITH THE
STRONGER STORMS.
TEMPERATURES WILL BE COOLER TODAY FOLLOWING THE
FRONTAL PASSAGE WITH READINGS AROUND 90 DEGREES OVER LOWER
ELEVATIONS. MOST OF THE STORMS WILL DIMINISH BY LATER THIS EVENING
WITH LACK OF ANY SIGNIFICANT FORCING ALOFT.
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 330 AM MDT FRI JUL 25 2014
ANOTHER WEAK BACKDOOR COLD FRONT IS EXPECTED TO PUSH ACROSS THE
PLAINS ON SATURDAY...RESULTING IN SLIGHT COOLING AND
STABILIZATION. THE AIRMASS WILL LIKELY REMAIN CAPPED OVER THE
NORTHEAST CORNER OF THE STATE...WHILE THE MOUNTAINS WILL STILL SEE
SCATTERED SHOWERS AND STORMS IN THE AFTERNOON AND EVENING AS
MID/UPPER LEVEL MOISTURE PLUME REMAINS ACROSS THE FORECAST AREA.
IN BETWEEN...THE ENVIRONMENT WILL BE MARGINAL FOR STORMS...BUT
WITH WESTERLY FLOW ALOFT WE SHOULD SEE ISOLATED SHOWERS/STORMS DRIFT
OFF THE FRONT RANGE AND HELP POP A FEW CELLS THROUGH THE CAP.
ON SUNDAY...TEMPERATURES WILL TREND A GOOD 5-10 DEGREES COOLER
ACROSS THE PLAINS BEHIND A DEEPENING POOL OF COOL AIR. THERE WILL
BE A THETA-E MINIMUM AND SLIGHT DRYING ACROSS MOST OF THE PLAINS
AS WELL...WHICH SHOULD EFFECTIVELY CUT OFF THE NORTHEAST PLAINS
FROM CONVECTION. MEANWHILE...MOUNTAIN AREAS WILL SEE ENOUGH
INSTABILITY FOR ANOTHER ROUND OF SCATTERED SHOWERS AND
STORMS...WITH A FEW POSSIBLY DRIFTING OFF THE FOOTHILLS INTO THE
I-25 CORRIDOR ONCE AGAIN BY LATE AFTERNOON/EVENING. AT THIS
TIME...LOOKS LIKE MAIN THREAT WOULD BE CLOSER TO THE PALMER DIVIDE
AREA HOWEVER AS AIRMASS FARTHER NORTH IS DRYING.
BY MONDAY...LOW LEVEL MOISTURE BEGINS TO RETURN AND INCREASE IN
SOUTH/SOUTHEAST FLOW. MEANWHILE...THETA-E RIDGE BUILDS IN/NEAR THE
FRONT RANGE WITH CAPES INCREASING TO AROUND 1500 J/KG. THIS ALONG
WITH SUFFICIENT SHEAR IN NORTHWEST FLOW ALOFT COULD LEAD TO A FEW
SEVERE STORMS.
ON TUESDAY...LOW LEVEL MOISTURE WILL LIKELY CONTINUE TO POOL ALONG
THE FRONT RANGE WHILE A SHORT WAVE IS STILL BEING ADVERTISED TO
DROP ACROSS THE REGION IN NORTHWEST FLOW ALOFT. THE UPSLOPE
COMPONENT IS ALSO PROGGED BY VARIOUS MODELS TO DEEPEN THROUGH 700
MB...COLLECTIVELY RESULTING IN A GOOD CHANCE OF SHOWERS AND
THUNDERSTORMS. CAPE MAY BE LIMITED BY COOLER TEMPERATURES...BUT
HIGH PRECIPITABLE WATER VALUES AND LIKELY SKINNY CAPE PROFILE
SUGGESTS POTENTIAL FOR HEAVY RAINFALL.
WEDNESDAY AND THURSDAY WILL FEATURE A CONTINUATION OF A COOL AND
SOMEWHAT UNSETTLED WEATHER PATTERN. BEST CHANCE SHOULD REFOCUS TO
THE ELEVATED TERRAIN THOUGH AS AIRMASS ON THE PLAINS WOULD BE MORE
STABLE BEHIND TUESDAYS WAVE AND WITH COOLER TEMPERATURES HOLDING
IN PLACE. PLAINS LOCATIONS MAY STRUGGLE TO REACH 80F BOTH DAYS.
&&
.AVIATION...(FOR THE TAFS THROUGH 12Z SATURDAY MORNING)
ISSUED AT 330 AM MDT FRI JUL 25 2014
SURFACE WINDS HAVE SETTLED INTO A SOUTHERLY DIRECTION AND WILL
STAY THAT WAY UNTIL WEAK COLD FRONT SHIFTS WINDS TO THE NORTHEAST
BETWEEN 14Z-15Z TIME RANGE. EXPECT ANOTHER ROUND OF SHOWERS AND
THUNDERSTORMS THIS AFTERNOON...WITH BEST CHANCE BETWEEN 21Z-24Z.
WILL ADJUST TIMING OF STORMS SLIGHTLY IN THE NEXT UPCOMING 12Z
ISSUANCE. AGAIN...MAY THREAT WILL BE HEAVY RAIN AND ERRATIC AND
GUSTY WINDS TO 40KT WITH THE STRONGER STORMS.
&&
.BOU WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...ENTREKIN
LONG TERM...BARJENBRUCH
AVIATION...ENTREKIN
AREA FORECAST DISCUSSION
NWS TALLAHASSEE FL
857 PM EDT Sat Jul 26 2014
.Near Term [Through Tonight]...
Clear skies and tranquil conditions are expected. An upper level
ridge to our west has kept most of the CWA dry today with only
isolated thunderstorms on the seabreeze. Expect seasonal
temperatures tonight in the low 70s inland with upper 70s along
coastal regions. With drier air in place, no rain is anticipated.
&&
.Aviation...
[Through 00Z Monday]...
With significantly drier air pushing down from
the north (especially at the mid levels), expect VFR conditions to
prevail through the period. Although some of the guidance did show
the potential for brief MVFR conditions at a few of the terminals
late tonight, the very reliable HRRR showed no Vis or Cig
restrictions at all. Also, no additional showers or storms are
expected during entire period with poor instability.
&&
.Prev Discussion [238 PM EDT]...
.Short Term [Sunday Through Monday Night]...
Ridging will continue to build in over the region on Sunday.
Expect little in the way of storm development on Sunday afternoon.
As a result, the building ridge and mostly sunny skies should
result in temperatures warming into the mid to upper 90s. The new
MAV guidance showing a couple of locations with temperatures 100
degrees or warmer seem a little suspect. In any event,
temperatures in the upper 90s with dewpoints in the lower 70s will
lead to afternoon heat indices in the 103 to 107 degree range, or
just below heat advisory criteria. Future shifts will make the
assessment for any advisories for Sunday.
On Monday, the ridge will break down as a trough moves into the
Tennessee River Valley pushing a cold front toward the Gulf Coast
States. Expect this boundary to help focus afternoon and evening
storm development, especially across Srn GA/AL where rain chances
have been increased to around 50 percent. With a weakening ridge
and scattered storms, expect highs only in the mid 90s.
.Long Term [Tuesday Through Saturday]...
Model guidance continues to be in excellent agreement in the
amplification of the Eastern CONUS trough through the long term
period. As the trough deepens on Monday night into Tuesday,
expect a cold front to move through the forecast area by Tuesday
afternoon. While there are some slight differences on timing and
magnitude of the cooler and drier air behind this frontal
boundary, there is good agreement now that the front will clear to
the south. Dry conditions should be in place across the region
from Tuesday evening into Thursday. This interval will also
feature some cool overnight lows, possibly dipping into the lower
60s in the colder spots across Southern Alabama. Even in the
Florida Big Bend, temperatures Wednesday and Thursday mornings
should drop into the upper 60s or just a bit cooler. Records for
this period at Tallahassee are as follows:
July 30 - 67 (1927)
July 31 - 63 (1896)
Aug 1 - 64 (1993)
By Thursday afternoon, moisture will begin to increase once again
across the forecast area as another upper disturbance within the
main upper trough moves into the forecast area. Unsettled
conditions look to return Friday and into next weekend with rain
chances increasing considerably. While overnight lows will return
to climatological norms for early August, daytime temperatures
will still be below normal due to plenty of convective activity.
.Marine...
Moderate westerly flow will persist into Monday when winds will
increase to cautionary levels into Tuesday ahead of a cold front
moving into the marine area. This cold front will pass south of
the waters on Tuesday evening with lighter winds returning.
.Fire Weather...
Red flag conditions are not expected over the next several days,
although high dispersion values are expected Sunday afternoon across
inland Florida big bend and south central Georgia.
.Hydrology...
The Shoal River at Mossy Head has reached bank full stage but is
not forecast to reach flood stage. All other area rivers are below
bank full stage. Thunderstorms could bring locally heavy rainfall
the next few days but widespread impacts are not expected.
&&
.Preliminary Point Temps/PoPs...
Tallahassee 74 96 78 96 75 / 10 10 10 30 30
Panama City 78 93 79 91 77 / 10 10 10 30 30
Dothan 75 97 77 94 71 / 10 10 10 50 40
Albany 75 97 78 95 72 / 10 10 10 50 40
Valdosta 73 98 77 98 73 / 10 10 10 30 30
Cross City 73 95 76 94 76 / 20 10 10 20 30
Apalachicola 77 91 79 92 78 / 10 10 10 20 30
&&
.TAE Watches/Warnings/Advisories...
FL...High Rip Current Risk until 10 PM CDT this evening for Coastal
Bay.
GA...None.
AL...None.
GM...None.
&&
$$
NEAR TERM...HARRIGAN/Dobbs
SHORT TERM...GODSEY
LONG TERM...GODSEY
AVIATION...GOULD
MARINE...GODSEY
FIRE WEATHER...MCDERMOTT
HYDROLOGY...WESTON
AREA FORECAST DISCUSSION
NWS TAMPA BAY RUSKIN FL
750 PM EDT SAT JUL 26 2014
.UPDATE (REST OF TONIGHT)...
23Z WATER VAPOR AND H4 RAP ANALYSIS SHOWING A FAIRLY BENIGN UPPER
LEVEL PATTERN OVER THE SOUTHERN TIER OF THE CONUS...CONSISTING OF
ELONGATED DEEP LEVEL RIDGING FROM THE 4 CORNERS REGION TO THE GULF
OF MEXICO AND FL PENINSULA. ANY SIGNIFICANT IMPULSES ARE CONFINED TO
THE NORTHERN STREAM FLOW OVER THE GREAT LAKES/OHIO VALLEY AND
NORTHEASTERN STATES.
AT THE SURFACE...SUBTROPICAL RIDGE AXIS IS ALIGNED ACROSS THE
CENTRAL/SOUTHERN PORTIONS OF THE PENINSULA INTO THE EASTERN GULF OF
MEXICO. THIS POSITION IS PROVIDING A LIGHT SW FLOW TO THE CENTRAL
AND NORTHERN PORTIONS OF THE FORECAST AREA...AND A VARIABLE LOW
LEVEL FLOW FURTHER SOUTH DOWN TO FORT MYERS.
THE SOUTHWEST FLOW PATTERN HAS ALLOWED MUCH OF THE DIURNAL SHOWER
AND STORM ACTIVITY TO PROGRESS ALL THE WAY TO THE I-95 CORRIDOR AND
OFF THE EASTERN SEABOARD. ONLY A FEW LINGERING ISOLATED SHOWERS
STILL LEFTOVER TO THE SOUTH OF I-4 THIS EVENING...AND CONSIDERING
CURRENT THERMODYNAMIC TRENDS AND CLIMO WOULD SUGGEST NOT MUCH
ADDITIONAL DEVELOPMENT DURING THE EVENING HOURS. HAVE REMOVED POPS
FROM THE TAMPA BAY AREA NORTHWARD FOR THE REMAINDER OF THE EVENING
WITH JUST A SLIGHT 20% CHANCE FURTHER SOUTH.
THE W/SW FLOW PATTERN AROUND THE SUBTROPICAL RIDGE IS FAVORABLE FOR
THE DEVELOPMENT OF LATE NIGHT/EARLY MORNING NOCTURNAL SHOWERS/STORMS
OVER THE NEAR SHORE WATERS OF THE EASTERN GULF OF MEXICO. MANY OF
THE LOCAL HIRES GUIDANCE MEMBERS ARE SHOWING THIS SCT DEVELOPMENT
AFTER 8-9Z...WITH A MOTION BRINGING THE ACTIVITY TOWARD THE COAST
TOWARD SUNRISE. INHERITED GRIDS SHOW THIS TREND OF INCREASING SHOWER
CHANCES NEAR THE COAST FROM MANATEE COUNTY NORTHWARD DURING THE LATE
NIGHT HOURS AND SEE LITTLE REASON FOR SIGNIFICANT CHANGES WITH THIS
FORECAST UPDATE.
IN TERMS OF TEMPERATURES...LOOKING FOR A WARM AND MUGGY SUMMER NIGHT
WITH LOW TEMPERATURES GENERALLY IN THE 70S INLAND...AND UPPER 70S TO
LOWER 80S AT THE BEACHES. ENJOY THE REMAINDER OF YOUR WEEKEND!
&&
.PREVIOUS DISCUSSION (SUNDAY)..
THE WEATHER SUNDAY WILL LIKELY BE CLOSE TO WHAT WE SAW TODAY WITH
PERHAPS A BIT LOWER COVERAGE OF SHOWERS/STORMS AS DEEP MOISTURE
DECREASES SLIGHTLY. OVERALL...EXPECT THE ACTIVITY TO BE CONFINED TO
MAINLY COASTAL ZONES IN THE MORNING WITH THE SHOWERS/STORMS THEN
SHIFTING INLAND DURING THE AFTERNOON HOURS. HIGHS ON SUNDAY TOPPING
OUT IN THE LOW TO MID 90S.
&&
.AVIATION...
VFR CONDITIONS PREVAIL ACROSS THE REGION THIS EVENING AS MOST SHOWER
AND STORM ACTIVITY HAS SHIFTED ALL THE WAY OVER TO THE I-95 CORRIDOR
OF THE STATE. JUST A FEW ISOLATED SHOWERS SOUTH OF I-4...BUT
GENERALLY NOT ANTICIPATING ANY FURTHER RESTRICTIONS THIS EVENING.
LATE TONIGHT INTO SUNDAY MORNING...WESTERLY FLOW SHOULD BRING AT
LEAST A CHANCE OF ISOLATED STORMS INTO KTPA/KPIE/KSRQ OFF THE GULF.
ALL TERMINALS WILL SEE A CHANCE OF SCT STORMS BETWEEN 15-19Z ON
SUNDAY WITH ACTIVITY THEN SHIFTING INLAND WITH DECREASING RAIN
CHANCES LATER IN THE AFTERNOON INTO SUNDAY EVENING.
&&
.MARINE...
WINDS WILL REMAIN LIGHT OUT OF THE SW TO WEST WITH SEAS A LIGHT
CHOP. THESE CONDITIONS WILL CONTINUE UNTIL MONDAY...WHEN THE RIDGE
DRIFTS SOUTH AS A FRONTAL BOUNDARY MOVES THROUGH NORTHERN FLORIDA
CAUSING A TIGHTER PRESSURE GRADIENT WHICH WILL PRODUCE INCREASING
WINDS AND SEAS ACROSS THE COASTAL WATERS THROUGH WEDNESDAY. THE ONLY
OTHER HAZARDS WILL BE HIGHER WINDS AND SEAS IN THE VICINITY OF
ISOLATED TO SCATTERED THUNDERSTORMS.
&&
.PRELIMINARY POINT TEMPS/POPS...
TPA 78 92 79 92 / 30 40 20 20
FMY 77 93 76 93 / 20 30 20 20
GIF 75 95 75 94 / 10 40 20 20
SRQ 76 91 78 92 / 20 30 20 20
BKV 72 94 74 94 / 30 30 20 20
SPG 80 92 78 91 / 30 40 20 20
&&
.TBW WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
GULF WATERS...NONE.
&&
$$
UPDATE/AVIATION...MROCZKA
MARINE...MCKAUGHAN
AREA FORECAST DISCUSSION
NWS MIAMI FL
1042 AM EDT FRI JUL 25 2014
.UPDATE...
DO NOT PLAN TO MAKE ANY MAJOR CHANGES TO THE CURRENT FORECAST. A
WEAK UPPER LEVEL LOW PRESSURE AREA OVER THE FLORIDA PANHANDLE THIS
MORNING HAS BECOME PINCHED OFF BETWEEN TWO STRONG RIDGES, ONE TO
OUR EAST AND EXTENDING ACROSS SOUTH FLORIDA WITH THE OTHER
CENTERED OVER THE SOUTHERN PLAINS. THIS HAS LOWERED THE 500MB
TEMPERATURES FROM A BALMY -4.7C YESTERDAY MORNING TO -7C AT 12Z
THIS MORNING FROM THE MFL SOUNDING. DUE TO THIS COOLING ALOFT, THE
MID LEVEL LAPSE RATES HAVE BECOME MORE CONDUCIVE TO CONVECTIVE
DEVELOPMENT AT 6.2C/KG. THIS FIGURE IS NOT HIGH, BUT SIGNIFICANTLY
MORE UNSTABLE THAN 24 HOURS AGO. THAT BEING SAID, WITH PLENTY OF
DIURNAL HEATING TAKING PLACE THIS MORNING (ALREADY 90 ACROSS THE
INTERIOR) THIS WILL SET THE STAGE FOR A MORE ACTIVE THUNDERSTORM
DAY. THE STEERING FLOW IS FROM NORTH TO SOUTH SO THE MAIN ACTION
IS EXPECTED TO BE OVER THE INTERIOR AREAS AND THE HRRR SEEMS TO
HAVE A GOOD HANDLE ON THIS THINKING. HOWEVER, WITH THE FLOW NEARLY
PARALLEL TO BOTH COASTS THERE COULD BE A FEW STORMS JUST INLAND
FROM THE COASTS UNTIL THE SEA BREEZES CAN STEER THE CELLS MORE
TO THE INTERIOR AREAS.
KOB
&&
.PREV DISCUSSION... /ISSUED 740 AM EDT FRI JUL 25 2014/
AVIATION...
MAINLY VFR CONDITIONS EXPECTED THROUGH THE TAF PERIOD. SHOWERS
AND STORMS WERE MOVING NORTH OVER THE GULF WATERS TO THE SOUTH OF
KAPF...BUT A FEW SHOWERS OR STORMS COULD GET NEAR THE TAF SITE
THROUGH EARLY AFTERNOON. SLIGHTLY DRIER AIR HAS MOVED INTO THE
EAST COAST TAF SITES OVERNIGHT. GUIDANCE IS INDICATING THAT
SHOWERS AND STORMS WILL FORM WELL AWAY FROM THE EAST COAST TAF
SITES THIS AFTERNOON DUE TO THE DRIER AIR...SO KEPT VCTS OUT OF
THE EAST COAST TAF SITES FOR NOW. LIGHT WINDS THIS MORNING WILL
SHIFT ONSHORE AND INCREASE TO AROUND 10 KNOTS AS SEA BREEZE
BOUNDARIES MOVE INLAND. LIGHT WINDS ARE EXPECTED AGAIN OVERNIGHT.
PREV DISCUSSION... /ISSUED 325 AM EDT FRI JUL 25 2014/
DISCUSSION...
RECENT SATELLITE IMAGERY INDICATES SOME RELATIVELY DRIER AIR
ACROSS THE NORTHWEST BAHAMAS WITH DEEP LAYERED MOISTURE AND
ASSOCIATED CLOUDINESS ACROSS THE FLORIDA STRAITS AND THE LOCAL
GULF WATERS. THE LATEST GUIDANCE INDICATES THAT THE DRIER AIR WILL
LIKELY REMAIN TO THE EAST OF THE REGION WHILE SOUTHERLY FLOW
ACROSS THE FLORIDA STRAITS TODAY WILL CONTINUE TO ADVECT DEEPER
MOISTURE INTO THE REGION THROUGH THE DAY. THE FORECAST PWAT FOR
THE MIAMI SOUNDING LOCATION AROUND 18Z IS ABOUT 1.7 INCHES.
ALTHOUGH THERE WILL BE WEAK SUBSIDENCE AT THE UPPER
LEVELS...AFTERNOON AND EVENING SHOWERS AND THUNDERSTORMS ARE STILL
EXPECTED ACROSS THE PENINSULA TODAY WITH THE GREATEST COVERAGE
EXPECTED IN THE WESTERN INTERIOR REGIONS WITH MOSTLY ISOLATED
ACTIVITY ACROSS THE LOCAL WATERS.
THERE IS LIKELY SOME SAHARAN DUST TO THE EAST OF THE BAHAMAS...BUT
LATEST GUIDANCE INDICATES IT IS DIFFUSE AND WILL NOT LIKELY HAVE
MUCH IMPACT ON SOUTH FLORIDA ALTHOUGH THE SKIES COULD BE MORE HAZY
THAN USUAL.
THE AFOREMENTIONED DEEPER MOISTURE EXPECTED ACROSS THE REGION
TODAY IS FORECAST TO LINGER ACROSS THE REGION ON SATURDAY...WITH
FORECAST PWAT VALUES STILL LINGERING AROUND 1.7 INCHES. LATEST
GUIDANCE INDICATES SOME DRIER AIR MOVING INTO THE FLORIDA STRAITS
BUT IS NOT FORECAST TO MOVE FAR ENOUGH NORTH TO HAMPER CONVECTION
ACROSS THE PENINSULA ON SATURDAY AFTERNOON WITH SHOWERS AND
THUNDERSTORMS EXPECTED WITH THE GREATEST COVERAGE EXPECTED IN THE
WESTERN INTERIOR.
BY SUNDAY THE DRIER AIR IN THE STRAITS IS FORECAST TO MOVE NORTH
WITH PWATS POSSIBLY DROPPING TO AROUND 1.2 INCHES WITH COVERAGE OF
SHOWERS ACROSS THE PENINSULA GREATLY REDUCED WITH MAINLY SCATTERED
ACTIVITY AROUND THE LAKE REGION FORECAST.
THE LATEST GLOBAL MODEL EXTENDED GUIDANCE INDICATES A COLD FRONT
COULD ENTER THE SOUTHEASTERN STATES ON MONDAY AND COULD HAVE
SUFFICIENT ENERGY TO MOVE INTO NORTH TO CENTRAL FLORIDA ON
WEDNESDAY. WILL HAVE TO SEE WHAT THE FUTURE GUIDANCE WILL DO WITH
THIS SCENARIO TO SAY WHAT...IF ANY...IMPACTS MIGHT BE EXPECTED IN
SOUTH FLORIDA LATER NEXT WEEK.
MARINE...
GENERALLY SOUTHEASTERLY WINDS 10 KNOTS OR LESS ARE FORECAST TO
PREVAIL ACROSS THE REGIONAL WATERS TODAY AND THROUGH THE UPCOMING
WEEKEND...WITH REGIONAL SEAS 2 FEET OR LESS THROUGH THIS PERIOD.
&&
.PRELIMINARY POINT TEMPS/POPS...
WEST PALM BEACH 91 78 89 78 / 30 20 40 20
FORT LAUDERDALE 90 81 90 81 / 20 20 30 20
MIAMI 91 79 91 80 / 30 20 30 20
NAPLES 92 77 90 76 / 30 20 30 20
&&
.MFL WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
AM...NONE.
GM...NONE.
&&
$$CV
AREA FORECAST DISCUSSION
NWS PEACHTREE CITY GA
724 PM EDT SAT JUL 26 2014
.SHORT TERM /TONIGHT THROUGH SUNDAY NIGHT/...
/ISSUED AT 252 PM EDT SAT JUL 26 2014/
18Z SURFACE ANALYSIS SHOWS A WEAK SURFACE TROUGH SITUATED ACROSS
SOUTH CENTRAL GA THIS AFTERNOON. WV/500MB ANALYSIS SHOWS A WEAK
SHEAR AXIS AND SHORTWAVE IN THE VICINITY OF THE OLD FRONT. A FEW
SHOWERS HAVE POPPED UP JUST OUTSIDE OF THE CWFA. THE LATEST RUNS OF
THE HRRR DO HAVE SOME CONVECTION DEVELOPING ACROSS THE SOUTHERN TIER
OF ZONES LATE THIS EVENING...SO WILL KEEP THE MENTION OF SLIGHT
CHANCE POPS IN THE FORECAST.
ANY CONVECTION ACROSS THE SOUTHERN ZONES LATE THIS AFTERNOON/EARLY
EVENING SHOULD DIMINISH QUICKLY WITH THE SETTING OF THE SUN. SKIES
ARE EXPECTED TO BE MOSTLY CLEAR WITH NEAR NORMAL LOW TEMPERATURES.
A SLIGHT CHANCE OF SHOWERS AND THUNDERSTORMS IS ONCE AGAIN POSSIBLE
SUNDAY AFTERNOON ACROSS THE SOUTHERN ZONES. DEEPER MOISTURE WILL
CONTINUE ACROSS THAT REGION...ALONG WITH THE WEAK/STATIONARY SURFACE
TROUGH. IN ADDITION...A COLD FRONT WILL BEGIN DROP SOUTH ACROSS THE
TN VALLEY. MODELS ARE PROGGING AN MCS TO DEVELOP AND MOVE NORTH OF
THE CWFA...BUT THE TAIL END OF THE SYSTEM HAS THE POTENTIAL TO CLIP
THE NORTHERN ZONES. POPS SHOULD BEGIN TO INCREASE TO AROUND 30 TO 40
PERCENT OVERNIGHT.
MODELS CONTINUE TO PROG ANY MCS TO WEAKEN AS IT APPROACHES THE CWFA
EARLY MONDAY MORNING. HOWEVER...THERE WILL BE FAIRLY DECENT SURFACE
INSTABILITY AND STEEP MID LEVEL LAPSE RATES PRESENT. MOST OF THE MID
LEVEL FORCING WILL SKATE BY TO THE NORTH. EVEN SO...DO THINK
THUNDERSTORMS...A FEW STRONG...COULD APPROACH THE NORTHERN ZONES BY
SUNRISE MONDAY. LOCALLY HEAVY RAINFALL WILL ALSO BE POSSIBLE.
NLISTEMAA
.LONG TERM /MONDAY THROUGH SATURDAY/...
/ISSUED AT 252 PM EDT SAT JUL 26 2014/
MAINLY ONLY TWEAKS TO THE LONG TERM BASED ON THE LATEST GUIDANCE.
WITH A MUCH COOLER AIRMASS BEHIND THE NEXT FRONT...SOME LOW
TEMPERATURE RECORDS WILL BE THREATENED WEDNESDAY AND THURSDAY
MORNINGS. LEANED HARD ON WPC MAX/MIN TEMPERATURES.
BDL
PREVIOUS DISCUSSION
FRONTAL SYSTEM PUSHES SOUTH OUT OF TN SUNDAY NIGHT AND INTO N GA
MONDAY MORNING. MOISTURE INCREASES ACROSS THE STATE SUNDAY AHEAD
OF THE APPROACHING FRONTAL SYSTEM. THIS FRONT IS EXPECTED TO MOVE
INTO NW GA BY 06Z-12Z MON AND PUSH SOUTH TO THE FL BORDER BY 12Z
TUE. AS THIS FRONT MOVES ACROSS GA INSTABILITIES INCREASE WITH
CAPES EXPECTED AROUND 1000 TO 3000 J/KG AND LIS RANGING FROM -3
TO -7. SHEAR VALUES DO NOT LOOK THAT IMPRESSIVE BUT THEY DO
INCREASE A BIT WITH THE FRONTAL PASSAGE. CURRENTLY SPC HAS THE DAY
2 SLIGHT RISK AREA COMING SOUTH OUT OF TN RIGHT TO OUR NORTHERN
BORDER BY 12Z MON. SPC AS GA ON DAY 3 IN JUST A SEE TEXT AREA.
WOULD NOT BE SURPRISED TO SEE THAT EXTENDED FURTHER SOUTH AS WE
GET CLOSER TO THE EVENT. ONCE THIS FRONT PASSES THROUGH...AN UPPER
LEVEL DEEP LONG WAVE TROUGH REMAINS POSITIONED OVER THE AREA
THROUGH MUCH OF NEXT WEEK...KEEPING LOWER DEW POINTS AND COOLER
TEMPERATURES IN PLACE AT LEAST THROUGH TUE/WED. MOISTURE BEGINS TO
INCREASE AGAIN BY THE END OF THE WORK WEEK ACROSS SOUTHERN PORTION
OF OUR CWA. WILL KEEP DIURNALLY DRIVEN SLIGHT TO LOW CHANCE POPS
IN ACROSS THE AREA DAYS 6 AND 7. BEGINNING TUESDAY...SHOULD SEE
BELOW AVERAGE TEMPERATURES WITH HIGHS IN THE UPPER 70S NORTH AND
LOW 80S ELSEWHERE...AND LOWS IN THE 60S.
01
&&
.CLIMATE...
RECORDS FOR 07-30
MAX TEMPERATURE MIN TEMPERATURE
STATION HIGH LOW HIGH LOW
------- ---------- ---------- ---------- ----------
KAHN 102 1999 69 1984 76 2010 60 1925
1915
KATL 98 1986 68 1984 78 1896 61 1936
1980
KCSG 102 2010 76 1984 79 2010 65 1957
1986
KMCN 103 1986 74 1984 76 2010 62 1920
2008
1958
RECORDS FOR 07-31
MAX TEMPERATURE MIN TEMPERATURE
STATION HIGH LOW HIGH LOW
------- ---------- ---------- ---------- ----------
KAHN 103 1999 71 1916 76 1931 59 1936
KATL 99 1999 62 1936 78 1915 59 1936
1986 1896
1980
KCSG 104 1986 74 1997 78 2011 66 1997
1981 2010
KMCN 105 1986 68 1936 77 1931 61 1936
&&
.AVIATION...
00Z UPDATE...
NO MAJOR CHANGES FROM THE PREVIOUS FORECAST. VFR CONDITIONS WILL
CONTINUE THROUGH THE FORECAST. THERE COULD BE PATCHY 5SM BR...MAINLY
AROUND THE AHN AREA...OTHERWISE EXPECT A SCATTERED CU FIELD TO
DEVELOP SUNDAY MORNING...HOWEVER AT THIS TIME NO PRECIPITATION IS
EXPECTED AT ANY OF THE TAF SITES. WINDS WILL BE LIGHT WEST/SOUTHWEST
TONIGHT...THEN SPEEDS OF 5 TO 10 KTS WITH A FEW GUSTS DURING THE DAY
SUNDAY.
//ATL CONFIDENCE...00Z UPDATE...
HIGH CONFIDENCE ALL ELEMENTS.
17
&&
.PRELIMINARY POINT TEMPS/POPS...
ATHENS 74 95 76 91 / 5 10 20 20
ATLANTA 74 93 76 87 / 5 10 20 20
BLAIRSVILLE 67 88 68 80 / 0 20 40 20
CARTERSVILLE 71 93 74 87 / 5 10 30 20
COLUMBUS 76 95 76 92 / 10 10 10 50
GAINESVILLE 73 93 74 87 / 5 10 30 20
MACON 74 95 77 93 / 10 10 10 50
ROME 71 94 74 87 / 0 20 40 20
PEACHTREE CITY 72 93 75 89 / 5 10 20 30
VIDALIA 77 95 78 94 / 10 20 10 50
&&
.FFC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...NLISTEMAA
LONG TERM....BDL
AVIATION...WILLIS/NLISTEMAA
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
1013 PM CDT SAT JUL 26 2014
.DISCUSSION...
736 PM CDT
OVERALL THREAT OF SEVERE WEATHER HAS DIMINISHED IN THE NEAR TERM
AND FOR THE REMAINDER OF THE EVENING...WITH CHANCES APPEARING LOW
FOR ADDITIONAL THUNDERSTORM DEVELOPMENT OVERNIGHT.
LATEST RADAR IMAGERY DEPICTING REMAINING SHOWERY ACTIVITY EXITING
THE SOUTHEAST CWA AS COMPLEX OVER CENTRAL ILLINOIS AND INDIANA
CONTINUES TO PROGRESS TO THE EAST...LEAVING THE CWA AND MUCH OF
THE REGION TO THE NORTH AND NORTHWEST DRY AT THIS TIME. LACK OF
ANY REAL GOOD FOCUS THIS EVENING AND A STRONG CAP STILL IN PLACE
OVER LINGERING STATIONARY BOUNDARY WILL LIMIT FURTHER
STRONG/SEVERE THUNDERSTORM DEVELOPMENT FOR THE REST OF THE
EVENING. DID ADJUST POPS TO KEEP LOW CHANCE/SLIGHT CHANCE POPS FOR
SHOWERS AND THUNDERSTORMS MAINLY FOR THE SOUTHERN CWA WITH THIS
LINGERING BOUNDARY STILL IN PLACE...BUT WITH ANY FURTHER
DEVELOPMENT MORE THAN LIKELY REMAINING MORE SHOWERY. ALSO GOING TO
ADD A SLIGHT CHANCE FOR SHOWERS AND THUNDERSTORMS ACROSS THE
NORTHERN CWA VERY LATE TONIGHT INTO EARLY SUNDAY MORNING. LARGE
VORT MAX ENTERING THE FAR NORTHERN PLAINS WILL SINK SOUTHEAST
THROUGH THE UPPER MIDWEST THROUGH SUNDAY MORNING. VORT LOBE OUT
AHEAD OF IT WILL SWING SOUTHEAST TO EASTERN IOWA AND SOUTHWEST
WISCONSIN AND COULD HELP THUNDERSTORM DEVELOPMENT IN THESE
AREAS...ESPECIALLY ALONG COLD FRONTAL BOUNDARY. CONFIDENCE OF
COVERAGE AND INTENSITY IS LOW AT THIS TIME BUT THERE IS A
POSSIBILITY FOR SOME OF THIS DEVELOPMENT TO REACH FAR NORTHERN
ILLINOIS BY VERY LATE TONIGHT AND EARLY SUNDAY MORNING. IF THIS
WERE TO OCCUR...WOULD EXPECT THAT HEAVY DOWNPOURS WOULD BE THE
MAIN THREAT.
VERY MOIST CONDITIONS IN A RELAXED SURFACE PATTERN WILL BE
CONDUCIVE FOR FOG DEVELOPMENT TONIGHT ESPECIALLY AS WINDS FURTHER
DIMINISH...AND SO HAVE ADDED MENTION OF FOG FOR THE ENTIRE CWA
TONIGHT.
RODRIGUEZ
//PREV DISCUSSION...
246 PM...FORECAST CONCERN AND CHALLENGE REMAINS CONVECTIVE TRENDS
THROUGH SUNDAY MORNING.
18Z SOUNDINGS FROM ILX AND DVN THIS AFTERNOON SHOW STRONG CAPPING
IN PLACE ACROSS THE AREA. RADAR IMAGERY SHOWS LIGHT RETURNS WHICH
ARE LIKELY ELEVATED SHOWERS/WEAK CONVECTION ROOTED FROM 800MB...
ABOVE THE CAP. NOT EXPECTING MUCH ACTIVITY ACROSS NORTHERN IL WITH
THIS CAP IN PLACE BUT ISOLATED SHOWERS/SPRINKLES WILL BE POSSIBLE.
THUNDERSTORMS OVER NORTHERN MO CONTINUE MOVING EAST AND INCREASING
IN COVERAGE BUT NOT MUCH ORGANIZATION YET. AS THIS ACTIVITY MOVES
EAST INTO THE MORE CAPPED AIR...IT MAY CONTINUE TO STRUGGLE TO
ORGANIZE INTO A SEVERE LINE/COMPLEX. THUS CONFIDENCE REGARDING
CONVECTIVE TRENDS ACROSS THE SOUTHERN CWA/CENTRAL IL/CENTRAL
INDIANA ARE DECREASING AT THE MOMENT. BUT WITH THE WARM FRONTAL
BOUNDARY NEARBY AND MID 70S DEWPOINTS POOLING SOUTH OF THE
FRONT...HAVE NOT MADE ANY CHANGES TO COVERAGE/TIMING. AND WHILE
SEVERE POTENTIAL REMAINS UNCERTAIN...SHOULD STORMS BECOME SEVERE
EARLIER THOUGHTS REMAIN ON TRACK FOR WIDESPREAD DAMAGING WINDS TO
BE THE MAIN THREAT...MAINLY SOUTH OF THE KANKAKEE RIVER.
THE GRADIENT MAY BECOME WEAK ENOUGH FOR LIGHT/CALM WINDS OVERNIGHT
ESPECIALLY OVER THE SOUTHERN HALF OF THE CWA. WHILE PRECIP
COVERAGE REMAINS UNCERTAIN...LOW LEVELS WILL REMAIN QUITE MOIST
AND FOG WILL BE POSSIBLE...AND WHERE ANY RAIN DOES FALL...COULD
BECOME LOCALLY DENSE.
A COLD FRONT WILL MOVE ACROSS THE AREA SUNDAY MORNING...LIKELY
MOVING EAST OF THE CWA BY 18Z. COULD BE ISOLATED/SCATTERED
THUNDERSTORMS ALONG/AHEAD OF THIS FRONT DURING THE MID MORNING
HOURS BUT WILL BE SHORT-LIVED WITH A PERIOD OF DRY CONDITIONS
EXPECTED MIDDAY/EARLY AFTERNOON POST FRONTAL. AS COOLER AIR
SPREADS ACROSS THE AREA...DIURNAL SHOWERS AND PERHAPS A FEW
THUNDERSTORMS WILL BE POSSIBLE MID/LATE SUNDAY AFTERNOON AND THIS
WOULD BE MOST LIKELY ACROSS NORTHERN IL. AS THIS COOLER AND DRIER
AIR ADVECTS INTO THE AREA...LOW LEVEL MIXING WILL BECOME QUITE
EFFICIENT. FORECAST SOUNDINGS SHOW 25-30 KTS IN THE MIXED LAYER
BY LATE AFTERNOON...THUS WINDY CONDITIONS ARE EXPECTED SUNDAY
AFTERNOON WITH WIND GUSTS AS HIGH AS 35 MPH.
A SECONDARY COLD FRONT WILL MOVE SOUTH ACROSS THE AREA SUNDAY
NIGHT USHERING IN EVEN COOLER AIR WITH HIGHS ON MONDAY ONLY IN THE
LOWER/MID 70S. A LARGE UPPER TROUGH WILL THEN REMAIN ACROSS MUCH
OF THE GREAT LAKES REGION AND EASTERN U.S. THROUGH THE END OF NEXT
WEEK. HIGH TEMPS WILL REMAIN BELOW NORMAL...GENERALLY IN THE MID/
UPPER 70S THROUGH THE END OF NEXT WEEK. IN ADDITION THERE WILL BE
AFTERNOON/EARLY EVENING CHANCES FOR ISOLATED SHOWERS/THUNDERSTORMS
JUST ABOUT EVERYDAY. CMS
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 03Z...
* SOME FOG POSSIBLE OVERNIGHT...MVFR VSBY PROBABLE WITH A CHANCE
OF IFR VSBY
* GUSTY WNW WINDS DEVELOP SUNDAY AFTERNOON
* SLIGHT CHANCE OF ISOLD SHRA OR TSRA SUNDAY
IZZI
//DISCUSSION...UPDATED 00Z...
DIMINISHING WINDS...CLEARING SKIES...AND VERY MOIST AIR MASS
FILTERING INTO THE AREA WILL SET THE STAGE FOR GROUND FOG TO
DEVELOP TONIGHT. THE MOST DENSE FOG SHOULD BE IN OUTLYING AREAS
BUT IFR CONDITIONS OR LOWER ARE A POSSIBILITY EVEN IN THE URBAN
AREAS. STRONG UPPER TROUGH WILL DIG SOUTHEAST INTO THE GREAT LAKES
REGION SUNDAY MORNING WITH INCREASING WINDS AFTER SUNRISE QUICKLY
MIXING OUT ANY FOG/VSBY EARLY SUNDAY MORNING. WINDS WILL REALLY
RAMP UP BY LATE MORNING/EARLY AFTERNOON SUNDAY AS BEHIND COLD
FRONT MOVING THROUGH THE AREA...GUSTS OF 25-30KT LOOK LIKE A GOOD
BET DURING THE AFTERNOON. NOT OUT OF THE QUESTION THAT THERE
COULD BE ISOLD SHRA OR EVENING TSRA AROUND SUNDAY...BUT EVEN IF
ANY FORM COVERAGE SHOULD BE LOW AND DURATION BRIEF IN ANY GIVEN
LOCATION SO NO REASON TO INCLUDE IN TERMINAL FORECAST AT THIS
TIME.
IZZI
//ORD AND MDW CONFIDENCE...UPDATED 03Z...
* MEDIUM-HIGH CONFIDENCE IN VSBY RESTRICTIONS DEVELOPING DUE TO
FOG OVERNIGHT BUT LOW CONFIDENCE IN HOW LOW VSBYS DROP
* HIGH CONFIDENCE IN OTHER FORECAST ELEMENTS
IZZI
//OUTLOOK FOR ORD/MDW FOR 12Z MONDAY-12Z SATURDAY...UPDATED 00Z...
MONDAY...VFR. MODERATELY STRONG NORTH-NORTHEAST WINDS.
TUESDAY THROUGH FRIDAY...PREDOMINANTLY VFR THROUGH THE PERIOD.
IZZI
&&
.MARINE...
230 PM CDT
AN ACTIVE PERIOD OF WEATHER IS SETTING UP FOR LAKE MICHIGAN FOR
THE NEXT FEW DAYS. A DIFFUSE AREA OF LOW PRESSURE OVER THE LAKE
THIS AFTERNOON WILL KEEP WINDS RELATIVELY LIGHT AND VARIABLE...BUT
A DEEPENING LOW PRESSURE SYSTEM DROPPING THROUGH THE UPPER
MISSISSIPPI VALLEY WILL LEAD TO STRENGTHENING SOUTHERLY WINDS
OVERNIGHT TONIGHT. THE LOW IS EXPECTED TO TRACK ACROSS CENTRAL
LAKE MICHIGAN LATE TONIGHT OR EARLY SUNDAY MORNING...DRAGGING A
STRONG COLD FRONT ACROSS THE LAKE AND TURNING WINDS NORTHERLY.
WINDS SHOULD QUICKLY INCREASE TO ARND 30 KT FOLLOWING THE LOW
PASSAGE AND FROPA AND DURING THE PERIOD OF STRONGEST COLD
ADVECTION...THE SEVERAL HOURS AFTER THE PASSAGE OF THE LOW AND
COLD FRONT...OCCASIONAL GALE FORCE GUSTS WILL BE POSSIBLE. WILL
ISSUE A SMALL CRAFT ADVISORY FOR THE NEAR SHORE WATERS FOR SUNDAY
MORNING THROUGH LATE MONDAY NIGHT FOR THE ILLINOIS NEARSHORE
WATERS AND SUNDAY MORNING THROUGH EARLY TUESDAY MORNING FOR THE
INDIANA WATERS AS WINDS AND WAVES WILL BOTH EXCEED ADVISORY
CRITERIA...WITH WAVES IN THE INDIANA NEAR SHORE WATERS REACHING AS
HIGH AS 7 TO 10 FT WITH OCCASIONAL HIGHER WAVES. A NORTHWESTERLY
TO NORTHERLY FETCH OVER THE ILLINOIS WATERS WILL KEEP WAVES A BIT
LOWER...BUT SHOULD EXCEED 4-5 FT BY THE END OF THE 5NM NEARSHORE
FETCH. HIGH PRESSURE BUILDING ACROSS CENTRAL PLAINS TO THE WESTERN
GREAT LAKES BY MONDAY AFTERNOON AND EVENING SHOULD ALLOW WINDS
AND WAVES TO SUBSIDE OVER THE LAKE. AS THE HIGH SETTLES INTO THE
OHIO VALLEY TUESDAY NIGHT AND WEDNESDAY...ANOTHER LOW PRESSURE
SYSTEM DROPPING SOUTHEAST THROUGH ONTARIO DRAGGING ANOTHER COLD
FRONT DOWN THE LAKE. THIS COMBINATION SHOULD KEEP MODEST WEST TO
NORTHWEST WINDS OVER THE LAKE THROUGH MIDWEEK. ANOTHER AREA OF
SPRAWLING HIGH PRESSURE IS FORECAST TO SPREAD ACROSS THE WESTERN
GREAT LAKES REGION BY LATE IN THE WEEK...BRING BACK LIGHT AND
VARIABLE WINDS AND LOW WAVES FOR LATE IN THE WEEK AND POSSIBLY
INTO NEXT WEEKEND.
KREIN
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...BEACH HAZARDS STATEMENT...INZ001-INZ002...NOON SUNDAY TO 5 AM
TUESDAY.
LM...SMALL CRAFT ADVISORY...LMZ740-LMZ741-LMZ742...NOON SUNDAY TO 11
PM MONDAY.
SMALL CRAFT ADVISORY...LMZ743-LMZ744-LMZ745...NOON SUNDAY TO 5
AM TUESDAY.
&&
$$
VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
WWW.FACEBOOK.COM/US.NATIONALWEATHERSERVICE.CHICAGO.GOV
WWW.TWITTER.COM/NWSCHICAGO
WWW.YOUTUBE.COM/NWSCHICAGO
[top]
Area Forecast Discussion
National Weather Service Lincoln IL
901 PM CDT Sat Jul 26 2014
.DISCUSSION...
ISSUED 901 PM CDT Sat Jul 26 2014
Already made one update to remove the watch, but will need to make
another to try to better represent expected conditions overnight.
Cold front is still northwest of the area and will be moving
through the area overnight. Some models indicate that some
additional showers and storms could develop overnight as the cold
front interacts with the moist air over the area. With lots of the
airmass worked over from the evening storms, chances may not be
that high for additional pcpn, but it remains a possibility. Fog
will also develop as skies become clear and winds become light.
Some spots already seeing fog, so will making sure this is added
in grids as well. Update will be forthcoming in a while.
Auten
&&
.AVIATION...
ISSUED 645 PM CDT Sat Jul 26 2014
Cluster of storms pushing east of CMI early this evening with
mainly stratiform rains to its west. A mix of VFR with some MVFR
cigs in the wake of the rains over the remainder of the forecast
area this evening. Still have the cold front to our northwest and
that won`t be pushing thru until Sunday morning. May see some addl
development late tonight as the front approaches late tonight but
the latest short term models are not very aggressive with any
redevelopment. One other possible concern will be with the potential
for fog to develop across the northern TAF sites just ahead of the
front as winds drop off to nearly calm for a time after 05z. What
fog and stratus that does develop late tonight should be gone by
15z as drier air filters southeast into the area behind the cold
front late Sunday morning into the afternoon hours. Surface winds
will be light southwest tonight and then switch into the west and
then northwest behind the cold front in the 14z-16z time frame.
We should see some gusts up to 20-23 kts by Sunday afternoon out
of the northwest as the much drier air moves in.
Smith
&&
.PREV DISCUSSION...
ISSUED 150 PM CDT Sat Jul 26 2014
ILX Local objective analysis as of 18z indicating the cap holding
strong across our northern forecast area where the frontal boundary
has slipped south of early this afternoon. Further south, we have
seen the cap weaken with Mixed Layer Cins down to around 100 along
the I70 corridor with Mixed Layer Capes were up to 3800 j/kg over
far west central IL where temps have climbed into the upper 80s
with dew points in the mid to upper 70s. 18z sounding from ILX and
DVN showing some moisture around 2500-3000 feet with a dry layer
from 850 to 500 mb and the cap holding strong at both locations.
SHORT TERM...Tonight through Tuesday
Storm coverage tonight the main forecast issue as all models weaken
the cap significantly this evening as the main upper level energy
starts to push into the region accompanied by cooling temperatures
aloft. HRRR and WRF-HOP ensembles were indicating the main convection
would be tracking across northern Missouri and into central to southeast
Illinois late this afternoon and evening, along the differential heating
boundary set up by the lower cloud cover. Further south, nothing but
sunshine and temps in the low to mid 90s, so quite a contrast across
central thru southeast Illinois which many times these storms tend to
propagate through. If the cap is breached there is plenty of CAPE and
Shear to interact with this evening with a fast moving QLCS still looking
more likely at least over our southern half of the forecast this evening.
Damaging winds and large hail will be the primary threats but enough
low level shear prevalent, especially near the boundary across our
northern counties, that a tornado could develop with a persistent
rotating updraft. Some of the storms could start to back-build later
this evening as the low level jet starts to back more into a southwest
to west direction increasing the threat for locally heavy rainfall.
Storms should start to edge out of our forecast area Sunday morning
as the front settles to our southeast by afternoon. Will still keep
low chance pops going, especially across the east but some fairly
decent dry air will be advecting in on a gusty west to northwest
wind during the afternoon. Cooler and much less humid air will filter
southeast into our area Monday and Tuesday as an unseasonably deep
trof settles in north of the Great Lakes.
LONG TERM...Wednesday through Saturday
The deep h5 trof will be the main weather story for much of this
period bringing rather cool temperatures for the first few days of
August, although latest guidance was not quite as cool as previous
runs as we see daytime highs edge back to or just above 80 degrees
starting on Wednesday. Rain chances remain a challenge as models
diverge with respect to timing of individual shortwaves that drop
southeast into the region bringing mainly diurnally driven shower
and thunderstorm chances, especially on Friday and Saturday.
Smith
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
707 PM CDT SAT JUL 26 2014
.DISCUSSION...
246 PM...FORECAST CONCERN AND CHALLENGE REMAINS CONVECTIVE TRENDS
THROUGH SUNDAY MORNING.
18Z SOUNDINGS FROM ILX AND DVN THIS AFTERNOON SHOW STRONG CAPPING
IN PLACE ACROSS THE AREA. RADAR IMAGERY SHOWS LIGHT RETURNS WHICH
ARE LIKELY ELEVATED SHOWERS/WEAK CONVECTION ROOTED FROM 800MB...
ABOVE THE CAP. NOT EXPECTING MUCH ACTIVITY ACROSS NORTHERN IL WITH
THIS CAP IN PLACE BUT ISOLATED SHOWERS/SPRINKLES WILL BE POSSIBLE.
THUNDERSTORMS OVER NORTHERN MO CONTINUE MOVING EAST AND INCREASING
IN COVERAGE BUT NOT MUCH ORGANIZATION YET. AS THIS ACTIVITY MOVES
EAST INTO THE MORE CAPPED AIR...IT MAY CONTINUE TO STRUGGLE TO
ORGANIZE INTO A SEVERE LINE/COMPLEX. THUS CONFIDENCE REGARDING
CONVECTIVE TRENDS ACROSS THE SOUTHERN CWA/CENTRAL IL/CENTRAL
INDIANA ARE DECREASING AT THE MOMENT. BUT WITH THE WARM FRONTAL
BOUNDARY NEARBY AND MID 70S DEWPOINTS POOLING SOUTH OF THE
FRONT...HAVE NOT MADE ANY CHANGES TO COVERAGE/TIMING. AND WHILE
SEVERE POTENTIAL REMAINS UNCERTAIN...SHOULD STORMS BECOME SEVERE
EARLIER THOUGHTS REMAIN ON TRACK FOR WIDESPREAD DAMAGING WINDS TO
BE THE MAIN THREAT...MAINLY SOUTH OF THE KANKAKEE RIVER.
THE GRADIENT MAY BECOME WEAK ENOUGH FOR LIGHT/CALM WINDS OVERNIGHT
ESPECIALLY OVER THE SOUTHERN HALF OF THE CWA. WHILE PRECIP
COVERAGE REMAINS UNCERTAIN...LOW LEVELS WILL REMAIN QUITE MOIST
AND FOG WILL BE POSSIBLE...AND WHERE ANY RAIN DOES FALL...COULD
BECOME LOCALLY DENSE.
A COLD FRONT WILL MOVE ACROSS THE AREA SUNDAY MORNING...LIKELY
MOVING EAST OF THE CWA BY 18Z. COULD BE ISOLATED/SCATTERED
THUNDERSTORMS ALONG/AHEAD OF THIS FRONT DURING THE MID MORNING
HOURS BUT WILL BE SHORT-LIVED WITH A PERIOD OF DRY CONDITIONS
EXPECTED MIDDAY/EARLY AFTERNOON POST FRONTAL. AS COOLER AIR
SPREADS ACROSS THE AREA...DIURNAL SHOWERS AND PERHAPS A FEW
THUNDERSTORMS WILL BE POSSIBLE MID/LATE SUNDAY AFTERNOON AND THIS
WOULD BE MOST LIKELY ACROSS NORTHERN IL. AS THIS COOLER AND DRIER
AIR ADVECTS INTO THE AREA...LOW LEVEL MIXING WILL BECOME QUITE
EFFICIENT. FORECAST SOUNDINGS SHOW 25-30 KTS IN THE MIXED LAYER
BY LATE AFTERNOON...THUS WINDY CONDITIONS ARE EXPECTED SUNDAY
AFTERNOON WITH WIND GUSTS AS HIGH AS 35 MPH.
A SECONDARY COLD FRONT WILL MOVE SOUTH ACROSS THE AREA SUNDAY
NIGHT USHERING IN EVEN COOLER AIR WITH HIGHS ON MONDAY ONLY IN THE
LOWER/MID 70S. A LARGE UPPER TROUGH WILL THEN REMAIN ACROSS MUCH
OF THE GREAT LAKES REGION AND EASTERN U.S. THROUGH THE END OF NEXT
WEEK. HIGH TEMPS WILL REMAIN BELOW NORMAL...GENERALLY IN THE MID/
UPPER 70S THROUGH THE END OF NEXT WEEK. IN ADDITION THERE WILL BE
AFTERNOON/EARLY EVENING CHANCES FOR ISOLATED SHOWERS/THUNDERSTORMS
JUST ABOUT EVERYDAY. CMS
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 00Z...
* SOME FOG POSSIBLE OVERNIGHT...MVFR VSBY PROBABLE WITH A CHANCE
OF IFR VSBY
* GUSTY WNW WINDS DEVELOP SUNDAY AFTERNOON
* SLIGHT CHANCE OF ISOLD SHRA OR TSRA SUNDAY
IZZI
//DISCUSSION...UPDATED 00Z...
DIMINISHING WINDS...CLEARING SKIES...AND VERY MOIST AIR MASS
FILTERING INTO THE AREA WILL SET THE STAGE FOR GROUND FOG TO
DEVELOP TONIGHT. THE MOST DENSE FOG SHOULD BE IN OUTLYING AREAS
BUT IFR CONDITIONS OR LOWER ARE A POSSIBILITY EVEN IN THE URBAN
AREAS. STRONG UPPER TROUGH WILL DIG SOUTHEAST INTO THE GREAT LAKES
REGION SUNDAY MORNING WITH INCREASING WINDS AFTER SUNRISE QUICKLY
MIXING OUT ANY FOG/VSBY EARLY SUNDAY MORNING. WINDS WILL REALLY
RAMP UP BY LATE MORNING/EARLY AFTERNOON SUNDAY AS BEHIND COLD
FRONT MOVING THROUGH THE AREA...GUSTS OF 25-30KT LOOK LIKE A GOOD
BET DURING THE AFTERNOON. NOT OUT OF THE QUESTION THAT THERE
COULD BE ISOLD SHRA OR EVENING TSRA AROUND SUNDAY...BUT EVEN IF
ANY FORM COVERAGE SHOULD BE LOW AND DURATION BRIEF IN ANY GIVEN
LOCATION SO NO REASON TO INCLUDE IN TERMINAL FORECAST AT THIS
TIME.
IZZI
//ORD AND MDW CONFIDENCE...UPDATED 00Z...
* MEDIUM-HIGH CONFIDENCE IN VSBY RESTRICTIONS DUE TO FOG TONIGHT
BUT LOW CONFIDENCE IN HOW LOW VSBYS DROP
* HIGH CONFIDENCE IN OTHER FORECAST ELEMENTS
IZZI
//OUTLOOK FOR ORD/MDW FOR 12Z MONDAY-12Z SATURDAY...UPDATED 00Z...
MONDAY...VFR. MODERATELY STRONG NORTH-NORTHEAST WINDS.
TUESDAY THROUGH FRIDAY...PREDOMINANTLY VFR THROUGH THE PERIOD.
IZZI
&&
.MARINE...
230 PM CDT
AN ACTIVE PERIOD OF WEATHER IS SETTING UP FOR LAKE MICHIGAN FOR
THE NEXT FEW DAYS. A DIFFUSE AREA OF LOW PRESSURE OVER THE LAKE
THIS AFTERNOON WILL KEEP WINDS RELATIVELY LIGHT AND VARIABLE...BUT
A DEEPENING LOW PRESSURE SYSTEM DROPPING THROUGH THE UPPER
MISSISSIPPI VALLEY WILL LEAD TO STRENGTHENING SOUTHERLY WINDS
OVERNIGHT TONIGHT. THE LOW IS EXPECTED TO TRACK ACROSS CENTRAL
LAKE MICHIGAN LATE TONIGHT OR EARLY SUNDAY MORNING...DRAGGING A
STRONG COLD FRONT ACROSS THE LAKE AND TURNING WINDS NORTHERLY.
WINDS SHOULD QUICKLY INCREASE TO ARND 30 KT FOLLOWING THE LOW
PASSAGE AND FROPA AND DURING THE PERIOD OF STRONGEST COLD
ADVECTION...THE SEVERAL HOURS AFTER THE PASSAGE OF THE LOW AND
COLD FRONT...OCCASIONAL GALE FORCE GUSTS WILL BE POSSIBLE. WILL
ISSUE A SMALL CRAFT ADVISORY FOR THE NEAR SHORE WATERS FOR SUNDAY
MORNING THROUGH LATE MONDAY NIGHT FOR THE ILLINOIS NEARSHORE
WATERS AND SUNDAY MORNING THROUGH EARLY TUESDAY MORNING FOR THE
INDIANA WATERS AS WINDS AND WAVES WILL BOTH EXCEED ADVISORY
CRITERIA...WITH WAVES IN THE INDIANA NEAR SHORE WATERS REACHING AS
HIGH AS 7 TO 10 FT WITH OCCASIONAL HIGHER WAVES. A NORTHWESTERLY
TO NORTHERLY FETCH OVER THE ILLINOIS WATERS WILL KEEP WAVES A BIT
LOWER...BUT SHOULD EXCEED 4-5 FT BY THE END OF THE 5NM NEARSHORE
FETCH. HIGH PRESSURE BUILDING ACROSS CENTRAL PLAINS TO THE WESTERN
GREAT LAKES BY MONDAY AFTERNOON AND EVENING SHOULD ALLOW WINDS
AND WAVES TO SUBSIDE OVER THE LAKE. AS THE HIGH SETTLES INTO THE
OHIO VALLEY TUESDAY NIGHT AND WEDNESDAY...ANOTHER LOW PRESSURE
SYSTEM DROPPING SOUTHEAST THROUGH ONTARIO DRAGGING ANOTHER COLD
FRONT DOWN THE LAKE. THIS COMBINATION SHOULD KEEP MODEST WEST TO
NORTHWEST WINDS OVER THE LAKE THROUGH MIDWEEK. ANOTHER AREA OF
SPRAWLING HIGH PRESSURE IS FORECAST TO SPREAD ACROSS THE WESTERN
GREAT LAKES REGION BY LATE IN THE WEEK...BRING BACK LIGHT AND
VARIABLE WINDS AND LOW WAVES FOR LATE IN THE WEEK AND POSSIBLY
INTO NEXT WEEKEND.
KREIN
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...BEACH HAZARDS STATEMENT...INZ001-INZ002...NOON SUNDAY TO 5 AM
TUESDAY.
LM...SMALL CRAFT ADVISORY...LMZ740-LMZ741-LMZ742...NOON SUNDAY TO 11
PM MONDAY.
SMALL CRAFT ADVISORY...LMZ743-LMZ744-LMZ745...NOON SUNDAY TO 5
AM TUESDAY.
&&
$$
VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
WWW.FACEBOOK.COM/US.NATIONALWEATHERSERVICE.CHICAGO.GOV
WWW.TWITTER.COM/NWSCHICAGO
WWW.YOUTUBE.COM/NWSCHICAGO
Area Forecast Discussion
National Weather Service Lincoln IL
649 PM CDT Sat Jul 26 2014
.DISCUSSION...
ISSUED 150 PM CDT Sat Jul 26 2014
ILX Local objective analysis as of 18z indicating the cap holding
strong across our northern forecast area where the frontal boundary
has slipped south of early this afternoon. Further south, we have
seen the cap weaken with Mixed Layer Cins down to around 100 along
the I70 corridor with Mixed Layer Capes were up to 3800 j/kg over
far west central IL where temps have climbed into the upper 80s
with dew points in the mid to upper 70s. 18z sounding from ILX and
DVN showing some moisture around 2500-3000 feet with a dry layer
from 850 to 500 mb and the cap holding strong at both locations.
SHORT TERM...Tonight through Tuesday
Storm coverage tonight the main forecast issue as all models weaken
the cap significantly this evening as the main upper level energy
starts to push into the region accompanied by cooling temperatures
aloft. HRRR and WRF-HOP ensembles were indicating the main convection
would be tracking across northern Missouri and into central to southeast
Illinois late this afternoon and evening, along the differential heating
boundary set up by the lower cloud cover. Further south, nothing but
sunshine and temps in the low to mid 90s, so quite a contrast across
central thru southeast Illinois which many times these storms tend to
propagate through. If the cap is breached there is plenty of CAPE and
Shear to interact with this evening with a fast moving QLCS still looking
more likely at least over our southern half of the forecast this evening.
Damaging winds and large hail will be the primary threats but enough
low level shear prevalent, especially near the boundary across our
northern counties, that a tornado could develop with a persistent
rotating updraft. Some of the storms could start to back-build later
this evening as the low level jet starts to back more into a southwest
to west direction increasing the threat for locally heavy rainfall.
Storms should start to edge out of our forecast area Sunday morning
as the front settles to our southeast by afternoon. Will still keep
low chance pops going, especially across the east but some fairly
decent dry air will be advecting in on a gusty west to northwest
wind during the afternoon. Cooler and much less humid air will filter
southeast into our area Monday and Tuesday as an unseasonably deep
trof settles in north of the Great Lakes.
LONG TERM...Wednesday through Saturday
The deep h5 trof will be the main weather story for much of this
period bringing rather cool temperatures for the first few days of
August, although latest guidance was not quite as cool as previous
runs as we see daytime highs edge back to or just above 80 degrees
starting on Wednesday. Rain chances remain a challenge as models
diverge with respect to timing of individual shortwaves that drop
southeast into the region bringing mainly diurnally driven shower
and thunderstorm chances, especially on Friday and Saturday.
&&
.AVIATION...
ISSUED 645 PM CDT Sat Jul 26 2014
Cluster of storms pushing east of CMI early this evening with
mainly stratiform rains to its west. A mix of VFR with some MVFR
cigs in the wake of the rains over the remainder of the forecast
area this evening. Still have the cold front to our northwest and
that won`t be pushing thru until Sunday morning. May see some addl
development late tonight as the front approaches late tonight but
the latest short term models are not very aggressive with any
redevelopment. One other possible concern will be with the potential
for fog to develop across the northern TAF sites just ahead of the
front as winds drop off to nearly calm for a time after 05z. What
fog and stratus that does develop late tonight should be gone by
15z as drier air filters southeast into the area behind the cold
front late Sunday morning into the afternoon hours. Surface winds
will be light southwest tonight and then switch into the west and
then northwest behind the cold front in the 14z-16z time frame.
We should see some gusts up to 20-23 kts by Sunday afternoon out
of the northwest as the much drier air moves in.
Smith
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
248 PM CDT FRI JUL 25 2014
.DISCUSSION...
324 AM CDT
SYNOPSIS...A TRICKY UNSETTLED FORECAST IS EXPECTED TODAY THROUGH
SUNDAY. THEN THINGS QUIET DOWN FOR THE BEGINNING OF THE WORK WEEK.
SATURDAY WILL BE THE WARMEST DAY IN THE FORECAST WITH HIGHS NEAR
90. TEMPS THEN FALL TO BELOW NORMAL SUNDAY AND SLOWLY BEGIN TO
CLIMB BACK TO NEAR 80 BY LATE NEXT WEEK.
TODAY AND TONIGHT...
AN UPPER LEVEL HIGH IS OVER THE SOUTHWEST U.S. AND SOUTHERN PLAINS
WHILE LOW PRESSURE IS OVER THE ALBERTA/SASKATCHEWAN BORDER. THE
HIGH WILL SLOWLY RETROGRADE THROUGH MONDAY AFTERNOON TO OVER THE SW
U.S. WHILE THE LOW PASSES OVER LAKE MICHIGAN SUNDAY EVENING. AT THE
SURFACE HIGH PRESSURE IS OVER THE OHIO RIVER VALLEY AND IT WILL MOVE
OFF THE ATLANTIC COAST TONIGHT. THERE ARE TWO SURFACE LOWS...ONE
OVER THE NORTHERN PLAINS AND THE SECOND CO-LOCATED WITH THE UPPER
LEVEL LOW OVER THE ALBERTA/SASKATCHEWAN BORDER.
CONVECTION IS ONGOING OVER WEST CENTRAL MINNESOTA AND IOWA VERY
EARLY THIS MORNING. THE STORMS WILL BE MOVING INTO A MORE STABLE
ENVIRONMENT AND THE LOW LEVEL JET WILL ALSO BE WEAKENING AS IT
PUSHES EAST. THERE IS HIGH CONFIDENCE THAT THE STORMS OVER IOWA WILL
WEAKEN AS THEY APPROACH THE CWA...BUT EXPECTING SHOWERS AND A COUPLE
OF STORMS TO REACH THE I-39 CORRIDOR BY MID MORNING. SOME GUIDANCE
MEMBERS SUGGEST SHOWERS AND STORMS COULD LINGER INTO THE MID
AFTERNOON HOURS BUT THINKING THEY WILL DISSIPATE BY THE EARLY
AFTERNOON.
HIGH CLOUDS WILL BE OVERHEAD AND MAY LIMIT HEATING A BIT...AS SUCH
LEFT HIGH TEMPS TODAY IN THE UPPER 70S.
MULTIPLE ROUNDS OF STORMS ARE EXPECTED WITH THE SECOND ROUND
SPREADING SOUTH THIS EVENING. THE LOW OVER THE PLAINS WILL WEAKEN AS
IT PUSHES EAST AND FORM AN OPEN TROUGH. THE LOWS WARM FRONT WILL
APPROACH THE REGION TONIGHT AND EXPECTING STORMS AHEAD OF IT. THE
NOSE OF THE LOW LEVEL JET WILL ALSO BE OVER NORTHWEST IL THIS
EVENING PROVIDING ADDITIONAL LIFT. CAPE WILL BE LIMITED WITH
MODEL SOUNDINGS SHOWING SHALLOW AREAS OF CAPE AT 1000 J/KG OR LESS.
PWAT VALUES WILL BE AROUND 1.9 INCHES SO TORRENTIAL DOWNPOURS ARE
THE MOST LIKELY HAZARD.
SATURDAY...
THE PLAINS LOW/TROUGH MOVES OVER THE MIDWEST WITH SATURDAY
HAVING THE BEST CHANCE FOR SEVERE WEATHER ESPECIALLY SOUTH OF I-88.
PWAT VALUES REMAIN HIGH AROUND 1.8 INCHES IN THE MORNING AND THEN
INCREASE TO 2-2.3 INCHES SOUTH OF I-80 SATURDAY AFTERNOON. CAPE
VALUES WILL BE MUCH MORE HEALTHY IN THE 3000 J/KG RANGE ESPECIALLY
ALONG AND SOUTH OF THE I-80 CORRIDOR. EXPECTING STORMS TO FIRE
ALONG THE LOWS COLD FRONT SATURDAY AFTERNOON AND EVENING WITH THE
CHANCES OF SHOWERS AND STORMS INCREASING AS YOU HEAD SOUTH. SOME OF
THESE STORMS MAY BE SEVERE WITH TORRENTIAL DOWNPOURS. HAIL AND WIND
LOOK TO BE THE MAIN SEVERE THREATS.
SATURDAY WILL FEEL UNPLEASANT TO MANY WITH HIGHS IN THE UPPER 80S
AND HIGH DEWPOINTS. MAX HEAT INDICES WILL BE IN THE 90S...WITH MID
TO UPPER 90 HEAT INDICES EXPECTED SOUTH OF I-80.
SUNDAY...
THE LOW OVER CANADA DRIFTS SOUTHEAST MOVING OVER WISCONSIN SUNDAY.
ADDITIONAL THUNDERSTORMS ARE POSSIBLE NORTH OF THE I-80
CORRIDOR...WITH THE BEST CHANCES ALONG THE IL/WI STATE LINE. THE
STORMS PUSH EAST OF THE CWA IN THE EVENING. COOLER AIR ASSOCIATED
WITH THE LOW ALSO SPREAD SOUTH WITH HIGHS ON SUNDAY ONLY EXPECTED TO
GET INTO THE LOW TO MID 80S. OVERNIGHT LOWS WILL BE AROUND
60...EXCEPT FOR DOWNTOWN WHICH WILL BE IN THE LOW 60S.
MONDAY THROUGH THURSDAY...
WE REMAIN UNDER THE UPPER LEVEL TROUGH THROUGH NEXT WEEK WITH A
SURFACE HIGH MOVING OVER THE REGION BY MID WEEK. THERE ARE
OCCASIONAL CHANCES OF SHOWERS AND STORMS BUT NONE OF THOSE CHANCES
LOOK ALL THAT IMPRESSIVE AT THIS POINT. THE BIGGER STORY WILL BE
ANOTHER EXTENDED PERIOD OF BELOW NORMAL TEMPS...ALTHOUGH
TEMPERATURES WILL BE SLOWLY RISING THROUGH THE END OF THE FORECAST
PERIOD.
JEE
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 20Z...
* SOUTH-SOUTHWEST WINDS GUSTING AROUND 20 KT THIS AFTERNOON.
* PERIOD OF MVFR CIGS 2500-3000 FT FOR A TIME THIS AFTN/EARLY
EVENING.
* CHANCE OF TSRA INCREASES LATE TONIGHT.
* PERIOD OF MVFR CIG/FOG POSSIBLE EARLY SATURDAY.
* WIND DIRECTION SOMEWHAT VARIABLE SAT MORNING.
RATZER
//DISCUSSION...UPDATED 20Z...
REMNANT BOUNDARY FROM IOWA CONVECTION HAS PUSHED ACROSS NORTHERN
IL WITH AN AREA OF MVFR STRATOCU SPREADING IN FROM THE NORTHWEST
BEHIND IT. HAVE INDICATED A FEW HOUR PERIOD OF CIGS FOR REMAINDER
OF AFTERNOON HOURS. SHRA/TSRA POTENTIAL CONTINUES TO APPEAR FAIRLY
LOW UNTIL LATER TONIGHT.
RATZER
PREVIOUS DISCUSSION FROM 18Z...
LOW PRESSURE WAS OVER EASTERN NEBRASKA AT MIDDAY...WITH A WARM
FRONT EXTENDING SOUTHEAST ACROSS THE LOWER MISSOURI RIVER VALLEY.
CIRCULATION ASSOCIATED WITH A MID-LEVEL DISTURBANCE/REMNANT MCV
OVER SOUTHERN WI WAS PRODUCING SOME RAIN ACROSS WI...BUT ONLY
SPOTTY SHRA INTO NORTHERN FOR THE MOST PART...WHILE A COMPLEX OF
THUNDERSTORMS CONTINUES TO MOVE SOUTHEAST ALONG THE MISSISSIPPI
RIVER INTO WESTERN/SOUTHERN IL. TERMINALS WILL REMAIN IN AN AREA
OF BROAD MOIST ASCENT INTO TONIGHT...WITH NOCTURNAL INCREASE IN
LOW LEVEL JET AND AN APPROACHING MID-LEVEL WAVE EXPECTED TO
EVENTUALLY SHIFT THE ELEVATED WARM FRONTAL ZONE EASTWARD AND
PRODUCE SCATTERED THUNDERSTORM THREAT OVER THE TERMINALS LATER
TONIGHT. PATTERN IS RELATIVELY MESSY HOWEVER...WITH FAIRLY LOW
CONFIDENCE IN TIMING DETAILS BEYOND THE OVERALL TREND AT THIS
TIME. AT THIS TIME HOWEVER...IT APPEARS THAT THE GREATEST
THUNDERSTORM THREAT WILL BE TOWARD/AFTER MIDNIGHT. LOW LEVEL JET
THEN TO BECOME MORE WEST/NORTHWEST BY SATURDAY
MORNING...DECREASING THUNDERSTORM POTENTIAL OVER TERMINALS AFTER
SUNRISE. SOME POTENTIAL WILL EXIST FOR BRIEF PERIOD OF MVFR
CEILING AND SOME GROUND FOG WILL EXIST EARLY SATURDAY MORNING
ESPECIALLY WHERE ORGANIZED RAINS FALL.
SOUTHERLY SURFACE WINDS GUSTING AROUND 20 KT THIS AFTERNOON IN
RESPONSE TO PRESSURE FALLS ACROSS WI/IA...APPARENTLY ENHANCED OVER
WESTERN IL BY WAKE LOW BEHIND MISSISSIPPI VALLEY THUNDERSTORM
COMPLEX. WINDS DIMINISH TONIGHT AFTER SUNSET AS GRADIENT WEAKENS
WITH APPROACH OF SURFACE TROUGH. WINDS SHOULD SHIFT MORE
WEST/NORTHWEST SATURDAY MORNING AS SURFACE TROUGH/COLD FRONT SAGS
SOUTHEAST ACROSS THE AREA...THOUGH GUIDANCE INDICATES SOME
VARIABILITY IN WIND DIRECTION IN WEAK GRADIENT NEAR THE TROUGH.
RATZER
//ORD AND MDW CONFIDENCE...UPDATED 120...
* MEDIUM CONFIDENCE IN PERIOD OF MVFR CIGS AT ORD/MDW THIS AFTN.
* LOW CONFIDENCE IN SHRA THIS AFTN/EVENING. MEDIUM CONFIDENCE IN
TSRA LATE TONIGHT.
* MEDIUM CONFIDENCE IN WIND TRENDS THIS AFTERNOON/EVENING. LOW
CONFIDENCE IN WIND DIRECTION DETAILS SATURDAY MORNING.
* LOW CONFIDENCE IN MVFR CIG/VIS DEVELOPMENT LATE TONIGHT/EARLY
SATURDAY.
RATZER
//OUTLOOK FOR ORD/MDW FOR 00Z SUNDAY-12Z FRIDAY...UPDATED 12Z...
SATURDAY NIGHT...SMALL CHANCE OF TSRA.
SUNDAY...CHANCE OF TSRA.
MONDAY...VFR LIKELY. STRONG NORTH-NORTHEAST WINDS.
TUESDAY...VFR.
WEDNESDAY-THURSDAY...SLIGHT CHANCE OF TSRA.
MTF
&&
.MARINE...
205 PM CDT
SOUTHERLY WINDS WILL CONTINUE TO STRENGTHEN OVER THE LAKE THIS
AFTERNOON AND TONIGHT AS HIGH PRESSURE MOVES OFF THE MID ATLANTIC
COAST WHILE LOW PRESSURE MOVES ACROSS THE MIDDLE AND UPPER
MISSISSIPPI VALLEY. THE SURFACE TROUGH LEADING TO THE INCREASE IN
WINDS WILL WEAKEN AND DISSIPATE SATURDAY. LOW PRESSURE DROPPING
OUT OF THE CANADIAN ROCKIES AND TRACKING ACROSS THE SOUTHERN
CANADIAN PRAIRIES WILL BECOME THE MORE DOMINANT FEATURE TO AFFECT
LAKE MICHIGAN AS IT TRACKS ACROSS LAKE SUPERIOR AND LAKE MICHIGAN
SATURDAY NIGHT. WINDS WILL BECOME WEAKER AND MORE VARIABLE WITH THE
LOW WEAKENING AS IT PASSES ACROSS THE WESTERN GREAT LAKES REGION
SATURDAY NIGHT. A SURGE OF MUCH COOLER AIR WITH PUSH SOUTH DOWN
THE LENGTH OF THE LAKE SUNDAY NIGHT AND MONDAY WITH WINDS BECOMING
NORTHERLY AND INCREASING TO ARND 30KT...WITH A FEW GALE FORCE
GUSTS TO 35 KT POSSIBLE. THE MOST LIKELY PERIOD TO SEE THE GALE
FORCE GUSTS SHOULD BE SATURDAY NIGHT INTO SUNDAY MORNING WHEN THE
COLD ADVECTION FOLLOWING THE PASSAGE OF THE LOW AND AN ASSOCIATED
COLD FRONT WILL BE THE STRONGEST. HIGH PRESSURE WILL QUICKLY BUILD
ACROSS THE PLAINS MONDAY AND SPREAD ACROSS THE UPPER MISSISSIPPI
VALLEY AND WESTERN GREAT LAKES MONDAY NIGHT AND THEN SETTLE INTO
THE OHIO VALLEY BY TUESDAY. ANOTHER WEAK LOW TRACKING
SOUTHEASTWARD ACROSS ONTARIO WILL KEEP GENERALLY NORTHWESTERLY TO
WESTERLY WINDS OVER THE LAKE INTO TUESDAY.
WHILE A GALE HEADLINE WILL NOT BE ISSUED WITH THE STRONG NORTH
WINDS SUNDAY NIGHT AND MONDAY...WINDS AND WAVES WILL LIKELY BE
SUFFICIENT TO NECESSITATE A SMALL CRAFT ADVISORY.
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:
WWW.FACEBOOK.COM/US.NATIONALWEATHERSERVICE.CHICAGO.GOV
WWW.TWITTER.COM/NWSCHICAGO
WWW.YOUTUBE.COM/NWSCHICAGO
Area Forecast Discussion
National Weather Service Lincoln IL
229 PM CDT Fri Jul 25 2014
.DISCUSSION...
ISSUED 220 PM CDT Fri Jul 25 2014
SHORT TERM...Tonight through Monday
Main forecast challenge revolves around the threat for severe
thunderstorms tomorrow afternoon and evening as a rather vigorous
upper wave shifts southeast into the upper Great Lakes. A secondary
concern will be with the Heat Index values forecast around 100
tomorrow afternoon.
Warm front forecast to shift northeast across the area tonight
with the better chances for storms along and to its northeast
tonight. That would put the higher pops across the east with
areas in the warm sector seeing a fairly significant warm layer
push in from the west. That capping inversion is now forecast to
break down quicker than earlier forecast as the upper dynamics
associated with the shortwave arrives sooner into our area tomorrow
afternoon. Any morning storms in the east should push out with a
frontal boundary drapped across parts of central Illinois as the main
upper level system approaches. Storms are expected to quickly initiate
tomorrow afternoon and spread east-southeast over central through
east central and southeast Illinois thru the evening hours. Extreme
instability levels and strong shear (Sfc base capes around 4000 j/kg,
and effective shear values 40-50 kts) suggest that supercells may
develop initially before translating into a fast moving Quasi Linear
Convective System by evening. Primary threats will be damaging wind
gusts, large hail and torrential rainfall. Any persistent rotating
storms that interact with the boundary across central Illinois have
the potential to produce a tornado or two early, before translating
to a fast moving line of storms by late afternoon or evening. Models
indicate the low level jet will veer rather quickly into a west
southwest component early tomorrow evening suggesting the potential
for the storms in the evening to back-build, increasing our chances
for heavy rainfall as well.
What`s left of the storms Sunday morning will be affecting southeast
Illinois with the threat for some heavy rainfall. Models indicate
the initial front should be pushing off to our east by mid-afternoon
so there is still a narrow window of opportunity for redevelopment
over parts of southeast Illinois in the afternoon on Sunday, with
low chance pops remaining to the northwest during the afternoon
hours. The cooler and drier air mass will start to settle southeast
into our area Sunday night and Monday as a large trof deepens in north
of the Great Lakes for early next week.
LONG TERM...Tuesday through Friday
Ensembles in reasonable agreement with respect to the unseasonably
deep trof over the eastern portion the country thru at least the first
half of the work week. Only question during this period will be with
several shortwaves forecast to rotate southeast into the lower Great
Lakes coupled with some rather cool temperatures aloft which may bring
us some diurnally driven showers later in the week. That would start
on Wednesday across our far northeast, with the instability shower
threat spreading over the remainder of the forecast area on Thursday
and Friday. Based on the 850 mb temp forecasts during this period, the
coolest temps will be Tue and Wed, with some day to day moderation seen
for the remainder of the period.
Smith
&&
.AVIATION...
ISSUED 1250 PM CDT Fri Jul 25 2014
MCS over central IL and ne MO with widespread showers and isolated
thunderstorms will gradually weaken during the afternoon as cap
increases and low level jet weakens. Showers have just passed se of
PIA and will end at BMI in next hour and along I-72 during mid
afternoon. MVFR ceilings and vsbys to occur at times with rain
showers with isolated thunderstorms possible especially at SPI and
possibly DEC next hour or so. Carried VCSH during mid afternoon
until sunset across central IL. Models have differ solutions
tonight and Sat morning with NAM model generally dry while RUC has
qpf just ne of BMI & CMI after 08Z/3 am tonight. Kept tafs dry
after dusk tonight into Sat morning and feel best chances of
convection will develop during Saturday afternoon as frontal
boundary drops southward toward I-72 into very unstable tropical
airmass. SSW winds 7-13 kts this afternoon and near or just below
10 kts tonight veer more sw on Sat morning. Wind shift with front
dropping south to occur after 18Z Sat especially at northern taf
sites of PIA and BMI.
07
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
112 PM CDT FRI JUL 25 2014
.DISCUSSION...
324 AM CDT
SYNOPSIS...A TRICKY UNSETTLED FORECAST IS EXPECTED TODAY THROUGH
SUNDAY. THEN THINGS QUIET DOWN FOR THE BEGINNING OF THE WORK WEEK.
SATURDAY WILL BE THE WARMEST DAY IN THE FORECAST WITH HIGHS NEAR
90. TEMPS THEN FALL TO BELOW NORMAL SUNDAY AND SLOWLY BEGIN TO
CLIMB BACK TO NEAR 80 BY LATE NEXT WEEK.
TODAY AND TONIGHT...
AN UPPER LEVEL HIGH IS OVER THE SOUTHWEST U.S. AND SOUTHERN PLAINS
WHILE LOW PRESSURE IS OVER THE ALBERTA/SASKATCHEWAN BORDER. THE
HIGH WILL SLOWLY RETROGRADE THROUGH MONDAY AFTERNOON TO OVER THE SW
U.S. WHILE THE LOW PASSES OVER LAKE MICHIGAN SUNDAY EVENING. AT THE
SURFACE HIGH PRESSURE IS OVER THE OHIO RIVER VALLEY AND IT WILL MOVE
OFF THE ATLANTIC COAST TONIGHT. THERE ARE TWO SURFACE LOWS...ONE
OVER THE NORTHERN PLAINS AND THE SECOND CO-LOCATED WITH THE UPPER
LEVEL LOW OVER THE ALBERTA/SASKATCHEWAN BORDER.
CONVECTION IS ONGOING OVER WEST CENTRAL MINNESOTA AND IOWA VERY
EARLY THIS MORNING. THE STORMS WILL BE MOVING INTO A MORE STABLE
ENVIRONMENT AND THE LOW LEVEL JET WILL ALSO BE WEAKENING AS IT
PUSHES EAST. THERE IS HIGH CONFIDENCE THAT THE STORMS OVER IOWA WILL
WEAKEN AS THEY APPROACH THE CWA...BUT EXPECTING SHOWERS AND A COUPLE
OF STORMS TO REACH THE I-39 CORRIDOR BY MID MORNING. SOME GUIDANCE
MEMBERS SUGGEST SHOWERS AND STORMS COULD LINGER INTO THE MID
AFTERNOON HOURS BUT THINKING THEY WILL DISSIPATE BY THE EARLY
AFTERNOON.
HIGH CLOUDS WILL BE OVERHEAD AND MAY LIMIT HEATING A BIT...AS SUCH
LEFT HIGH TEMPS TODAY IN THE UPPER 70S.
MULTIPLE ROUNDS OF STORMS ARE EXPECTED WITH THE SECOND ROUND
SPREADING SOUTH THIS EVENING. THE LOW OVER THE PLAINS WILL WEAKEN AS
IT PUSHES EAST AND FORM AN OPEN TROUGH. THE LOWS WARM FRONT WILL
APPROACH THE REGION TONIGHT AND EXPECTING STORMS AHEAD OF IT. THE
NOSE OF THE LOW LEVEL JET WILL ALSO BE OVER NORTHWEST IL THIS
EVENING PROVIDING ADDITIONAL LIFT. CAPE WILL BE LIMITED WITH
MODEL SOUNDINGS SHOWING SHALLOW AREAS OF CAPE AT 1000 J/KG OR LESS.
PWAT VALUES WILL BE AROUND 1.9 INCHES SO TORRENTIAL DOWNPOURS ARE
THE MOST LIKELY HAZARD.
SATURDAY...
THE PLAINS LOW/TROUGH MOVES OVER THE MIDWEST WITH SATURDAY
HAVING THE BEST CHANCE FOR SEVERE WEATHER ESPECIALLY SOUTH OF I-88.
PWAT VALUES REMAIN HIGH AROUND 1.8 INCHES IN THE MORNING AND THEN
INCREASE TO 2-2.3 INCHES SOUTH OF I-80 SATURDAY AFTERNOON. CAPE
VALUES WILL BE MUCH MORE HEALTHY IN THE 3000 J/KG RANGE ESPECIALLY
ALONG AND SOUTH OF THE I-80 CORRIDOR. EXPECTING STORMS TO FIRE
ALONG THE LOWS COLD FRONT SATURDAY AFTERNOON AND EVENING WITH THE
CHANCES OF SHOWERS AND STORMS INCREASING AS YOU HEAD SOUTH. SOME OF
THESE STORMS MAY BE SEVERE WITH TORRENTIAL DOWNPOURS. HAIL AND WIND
LOOK TO BE THE MAIN SEVERE THREATS.
SATURDAY WILL FEEL UNPLEASANT TO MANY WITH HIGHS IN THE UPPER 80S
AND HIGH DEWPOINTS. MAX HEAT INDICES WILL BE IN THE 90S...WITH MID
TO UPPER 90 HEAT INDICES EXPECTED SOUTH OF I-80.
SUNDAY...
THE LOW OVER CANADA DRIFTS SOUTHEAST MOVING OVER WISCONSIN SUNDAY.
ADDITIONAL THUNDERSTORMS ARE POSSIBLE NORTH OF THE I-80
CORRIDOR...WITH THE BEST CHANCES ALONG THE IL/WI STATE LINE. THE
STORMS PUSH EAST OF THE CWA IN THE EVENING. COOLER AIR ASSOCIATED
WITH THE LOW ALSO SPREAD SOUTH WITH HIGHS ON SUNDAY ONLY EXPECTED TO
GET INTO THE LOW TO MID 80S. OVERNIGHT LOWS WILL BE AROUND
60...EXCEPT FOR DOWNTOWN WHICH WILL BE IN THE LOW 60S.
MONDAY THROUGH THURSDAY...
WE REMAIN UNDER THE UPPER LEVEL TROUGH THROUGH NEXT WEEK WITH A
SURFACE HIGH MOVING OVER THE REGION BY MID WEEK. THERE ARE
OCCASIONAL CHANCES OF SHOWERS AND STORMS BUT NONE OF THOSE CHANCES
LOOK ALL THAT IMPRESSIVE AT THIS POINT. THE BIGGER STORY WILL BE
ANOTHER EXTENDED PERIOD OF BELOW NORMAL TEMPS...ALTHOUGH
TEMPERATURES WILL BE SLOWLY RISING THROUGH THE END OF THE FORECAST
PERIOD.
JEE
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 18Z...
* SOUTH WINDS GUSTING AROUND 20 KT THIS AFTERNOON.
* POTENTIAL FOR A FEW SCATTERED SHRA THIS AFTERNOON.
* CHANCE OF TSRA INCREASES LATE TONIGHT.
* PERIOD OF MVFR CIG/FOG POSSIBLE EARLY SATURDAY.
* WIND DIRECTION SOMEWHAT VARIABLE SAT MORNING.
RATZER
//DISCUSSION...UPDATED 18Z...
LOW PRESSURE WAS OVER EASTERN NEBRASKA AT MIDDAY...WITH A WARM
FRONT EXTENDING SOUTHEAST ACROSS THE LOWER MISSOURI RIVER VALLEY.
CIRCULATION ASSOCIATED WITH A MID-LEVEL DISTURBANCE/REMNANT MCV
OVER SOUTHERN WI WAS PRODUCING SOME RAIN ACROSS WI...BUT ONLY
SPOTTY SHRA INTO NORTHERN FOR THE MOST PART...WHILE A COMPLEX OF
THUNDERSTORMS CONTINUES TO MOVE SOUTHEAST ALONG THE MISSISSIPPI
RIVER INTO WESTERN/SOUTHERN IL. TERMINALS WILL REMAIN IN AN AREA
OF BROAD MOIST ASCENT INTO TONIGHT...WITH NOCTURNAL INCREASE IN
LOW LEVEL JET AND AN APPROACHING MID-LEVEL WAVE EXPECTED TO
EVENTUALLY SHIFT THE ELEVATED WARM FRONTAL ZONE EASTWARD AND
PRODUCE SCATTERED THUNDERSTORM THREAT OVER THE TERMINALS LATER
TONIGHT. PATTERN IS RELATIVELY MESSY HOWEVER...WITH FAIRLY LOW
CONFIDENCE IN TIMING DETAILS BEYOND THE OVERALL TREND AT THIS
TIME. AT THIS TIME HOWEVER...IT APPEARS THAT THE GREATEST
THUNDERSTORM THREAT WILL BE TOWARD/AFTER MIDNIGHT. LOW LEVEL JET
THEN TO BECOME MORE WEST/NORTHWEST BY SATURDAY
MORNING...DECREASING THUNDERSTORM POTENTIAL OVER TERMINALS AFTER
SUNRISE. SOME POTENTIAL WILL EXIST FOR BRIEF PERIOD OF MVFR
CEILING AND SOME GROUND FOG WILL EXIST EARLY SATURDAY MORNING
ESPECIALLY WHERE ORGANIZED RAINS FALL.
SOUTHERLY SURFACE WINDS GUSTING AROUND 20 KT THIS AFTERNOON IN
RESPONSE TO PRESSURE FALLS ACROSS WI/IA...APPARENTLY ENHANCED OVER
WESTERN IL BY WAKE LOW BEHIND MISSISSIPPI VALLEY THUNDERSTORM
COMPLEX. WINDS DIMINISH TONIGHT AFTER SUNSET AS GRADIENT WEAKENS
WITH APPROACH OF SURFACE TROUGH. WINDS SHOULD SHIFT MORE
WEST/NORTHWEST SATURDAY MORNING AS SURFACE TROUGH/COLD FRONT SAGS
SOUTHEAST ACROSS THE AREA...THOUGH GUIDANCE INDICATES SOME
VARIABILITY IN WIND DIRECTION IN WEAK GRADIENT NEAR THE TROUGH.
RATZER
//ORD AND MDW CONFIDENCE...UPDATED 18Z...
* LOW CONFIDENCE IN SHRA THIS AFTN/EVENING. MEDIUM CONFIDENCE IN
TSRA LATE TONIGHT.
* MEDIUM CONFIDENCE IN WIND TRENDS THIS AFTERNOON/EVENING. LOW
CONFIDENCE IN WIND DIRECTION DETAILS SATURDAY MORNING.
* LOW CONFIDENCE IN MVFR CIG/VIS DEVELOPMENT LATE TONIGHT/EARLY
SATURDAY.
RATZER
//OUTLOOK FOR ORD/MDW FOR 00Z SUNDAY-12Z FRIDAY...UPDATED 12Z...
SATURDAY NIGHT...SMALL CHANCE OF TSRA.
SUNDAY...CHANCE OF TSRA.
MONDAY...VFR LIKELY. STRONG NORTH-NORTHEAST WINDS.
TUESDAY...VFR.
WEDNESDAY-THURSDAY...SLIGHT CHANCE OF TSRA.
MTF
&&
.MARINE...
228 AM CDT
SOUTHERLY FLOW WILL INCREASE OVER THE LAKE TODAY AS HIGH PRESSURE
SCOOTS EASTWARD FROM THE OHIO RIVER VALLEY. THE SURFACE TROUGH
LEADING TO THE INCREASE IN WINDS WILL ARRIVE EARLY
SATURDAY...HOWEVER WEAKEN TO THE POINT WHERE IT WILL NOT SHIFT THE
WINDS MUCH IF ANY FROM THE SOUTH-SOUTHWEST. THE LOW PRESSURE
DRIVING THIS TROUGH WILL EVOLVE OVER THE LAKE ON SUNDAY TURNING
WINDS NORTHERLY AND DRIVING A SHARP INCREASE IN SPEEDS SUNDAY
NIGHT AND PERSISTING INTO MONDAY. FOR JULY STANDARDS THESE WIND
SPEEDS ONCE AGAIN WILL BE QUITE STRONG WITH EVEN POSSIBLY SOME
GALE FORCE NORTHERLY GUSTS LATE SUNDAY NIGHT INTO MONDAY MORNING.
WITH ONCE AGAIN A LONG FETCH WAVES SHOULD REACH HEIGHTS OF OVER 6
FT OVER MUCH OF THE LAKE WITH EVEN POSSIBLY UP TO 10 FT AGAIN
ACROSS THE FAR SOUTH...PRIMARILY NEAR THE INDIANA SHORE.
MTF
&&
.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:
WWW.FACEBOOK.COM/US.NATIONALWEATHERSERVICE.CHICAGO.GOV
WWW.TWITTER.COM/NWSCHICAGO
WWW.YOUTUBE.COM/NWSCHICAGO
Area Forecast Discussion
National Weather Service Lincoln IL
1251 PM CDT Fri Jul 25 2014
.DISCUSSION...
ISSUED 1043 AM CDT Fri Jul 25 2014
Already did a major update to the forecast today for more cloud
cover along with much higher chances of showers along with
isolated thunderstorms for areas west of I-57 into early
afternoon. Continued a chance of showers and thunderstorms during
mid/late afternoon over central IL with just slight chances in
southeast IL while far southeast IL near Lawrence county to likely
stay dry today. Trimmed highs down a bit into upper 70s to around
80 degrees due to more showers and clouds over central IL.
MCS over eastern IA, northeast MO and nw half of IL has held
together longer than earlier expected as it tracked se to along
I-72 by late morning. Just isolated thunderstorms west of I-55
while more numerous thunderstorms and heavier rains have been on
western edge of MCS over ne MO and se IA. SPC has 5% risk of large
hail and damaging wind gusts nw of a Shelbville to Tuscola line
today so severe threat quite low today.
12Z ILX sounding showing a lot of dry air below 650 mb so this
should weaken the convection into this afternoon as it continues
moving se toward I-70. Think HRRR model is holding onto convection
too long as it moves it into southeast IL by mid afternoon. NAM
and RUC/RAP model on the other hand appears too quick diminishing
convection during early afternoon. Will blend between the wetter
HRRR and drier NAM/RUC models for the afternoon forecast.
Southerly winds increasing to 10-15 mph this afternoon between
1021 mb high pressure over WV and ridging into the ohio river
valley and 1006 mb low pressure in eastern SD/NE to bring in a bit
more humid air into central IL this afternoon. Dewpoints currently
in the upper 50s to around 60F rising to between 60-65F during the
afternoon and highest west of the IL river.
07
&&
.AVIATION...
ISSUED 1250 PM CDT Fri Jul 25 2014
MCS over central IL and ne MO with widespread showers and isolated
thunderstorms will gradually weaken during the afternoon as cap
increases and low level jet weakens. Showers have just passed se of
PIA and will end at BMI in next hour and along I-72 during mid
afternoon. MVFR ceilings and vsbys to occur at times with rain
showers with isolated thunderstorms possible especially at SPI and
possibly DEC next hour or so. Carried VCSH during mid afternoon
until sunset across central IL. Models have differ solutions
tonight and Sat morning with NAM model generally dry while RUC has
qpf just ne of BMI & CMI after 08Z/3 am tonight. Kept tafs dry
after dusk tonight into Sat morning and feel best chances of
convection will develop during Saturday afternoon as frontal
boundary drops southward toward I-72 into very unstable tropical
airmass. SSW winds 7-13 kts this afternoon and near or just below
10 kts tonight veer more sw on Sat morning. Wind shift with front
dropping south to occur after 18Z Sat especially at northern taf
sites of PIA and BMI.
07
&&
.PREV DISCUSSION...
ISSUED 247 AM CDT Fri Jul 25 2014
Illinois remains on the periphery of high pressure centered over
Ohio early this morning. To our northwest, convection has been
ramping up quickly over the last couple hours in central and
northwest Iowa along a warm front, as the low level jet increases
from the central Plains. The initial concern for this forecast
package involves how much of this convection will affect our area
today. However, the main forecast issue is with severe weather
potential Saturday afternoon and evening.
SHORT TERM...Today through Saturday Night:
The track of this developing thunderstorm cluster has necessitated
some noticeable changes to the going forecast for today. Earlier
grids mainly had the north half affected by the overnight
convection. Latest high-res models are all indicating a
southeast track, which would favor the western parts of the CWA.
However, very dry conditions above 850 mb were observed on our
evening sounding, and LAPS soundings for Peoria and Springfield at
1 am still showed a sizable dry wedge around 800 mb. Model
soundings show this eroding somewhat by mid morning but not
completely going away, so eastward extent is still a bit in
question. Will have the highest PoP`s from around Rushville to
Jacksonville, with lower chances spreading eastward as far as
I-57. Rain chances should be diminishing during the afternoon as
the atmosphere becomes more capped.
Evening models in general agreement with a shortwave tracking
along the periphery of the upper ridge to our southwest, but
convective alignment is more variable. The general consensus is
for a convective complex to develop to our north by late evening.
The ECMWF and GEM track this southeast and just brush by the
forecast area, while the NAM and GFS show some development
extending southwest along a frontal boundary into Kansas. Have not
made much change here at this point, since leftover boundaries
from the daytime activity may also contribute and are not
adequately handled by the synoptic models.
The frontal boundary will likely hang up somewhere in the I-72
vicinity on Saturday. Have gone with only slight chance PoP`s
during the morning, then increased them to around 30-40% in the
afternoon as the cap starts to erode. Very unstable conditions
will be developing, as dew points rise into the mid 70s and yield
CAPE values well over 3000 J/kg. 0-6km shear around 35 knots is
progged by evening, when the best storm chances in our area are
likely. Latest SPC Day2 outlook shows 30% severe probabilities
over the entire forecast area, with damaging winds favored.
Precipitable waters rising to just over 2 inches will also result
in locally heavy rains, and the ECMWF and GFS indicate some
training echoes could also be a concern.
Some secondary concerns also exist on Saturday for heat advisory
potential. With dew points rising into the mid 70s, am expecting
heat index values of 100-102 over most areas except perhaps along
and north of I-74. This is just shy of the 105F criteria for this
area.
LONG TERM...Sunday through Thursday:
Any lingering rain on Sunday will likely be in the morning, before
a cold front passes. This will be ahead of an upper low, currently
entering southwest Saskatchewan, that will be opening up as it
drops southeast through the Great Lakes region. This will evolve
into a broad upper trough that will dominate the eastern U.S.
throughout the week, bringing another period of cooler conditions.
Monday is likely to be the coolest day, with highs mainly in the
mid 70s, and comfortable humidity levels to persist much of the
work week.
Geelhart
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
1121 AM CDT FRI JUL 25 2014
.DISCUSSION...
324 AM CDT
SYNOPSIS...A TRICKY UNSETTLED FORECAST IS EXPECTED TODAY THROUGH
SUNDAY. THEN THINGS QUIET DOWN FOR THE BEGINNING OF THE WORK WEEK.
SATURDAY WILL BE THE WARMEST DAY IN THE FORECAST WITH HIGHS NEAR
90. TEMPS THEN FALL TO BELOW NORMAL SUNDAY AND SLOWLY BEGIN TO
CLIMB BACK TO NEAR 80 BY LATE NEXT WEEK.
TODAY AND TONIGHT...
AN UPPER LEVEL HIGH IS OVER THE SOUTHWEST U.S. AND SOUTHERN PLAINS
WHILE LOW PRESSURE IS OVER THE ALBERTA/SASKATCHEWAN BORDER. THE
HIGH WILL SLOWLY RETROGRADE THROUGH MONDAY AFTERNOON TO OVER THE SW
U.S. WHILE THE LOW PASSES OVER LAKE MICHIGAN SUNDAY EVENING. AT THE
SURFACE HIGH PRESSURE IS OVER THE OHIO RIVER VALLEY AND IT WILL MOVE
OFF THE ATLANTIC COAST TONIGHT. THERE ARE TWO SURFACE LOWS...ONE
OVER THE NORTHERN PLAINS AND THE SECOND CO-LOCATED WITH THE UPPER
LEVEL LOW OVER THE ALBERTA/SASKATCHEWAN BORDER.
CONVECTION IS ONGOING OVER WEST CENTRAL MINNESOTA AND IOWA VERY
EARLY THIS MORNING. THE STORMS WILL BE MOVING INTO A MORE STABLE
ENVIRONMENT AND THE LOW LEVEL JET WILL ALSO BE WEAKENING AS IT
PUSHES EAST. THERE IS HIGH CONFIDENCE THAT THE STORMS OVER IOWA WILL
WEAKEN AS THEY APPROACH THE CWA...BUT EXPECTING SHOWERS AND A COUPLE
OF STORMS TO REACH THE I-39 CORRIDOR BY MID MORNING. SOME GUIDANCE
MEMBERS SUGGEST SHOWERS AND STORMS COULD LINGER INTO THE MID
AFTERNOON HOURS BUT THINKING THEY WILL DISSIPATE BY THE EARLY
AFTERNOON.
HIGH CLOUDS WILL BE OVERHEAD AND MAY LIMIT HEATING A BIT...AS SUCH
LEFT HIGH TEMPS TODAY IN THE UPPER 70S.
MULTIPLE ROUNDS OF STORMS ARE EXPECTED WITH THE SECOND ROUND
SPREADING SOUTH THIS EVENING. THE LOW OVER THE PLAINS WILL WEAKEN AS
IT PUSHES EAST AND FORM AN OPEN TROUGH. THE LOWS WARM FRONT WILL
APPROACH THE REGION TONIGHT AND EXPECTING STORMS AHEAD OF IT. THE
NOSE OF THE LOW LEVEL JET WILL ALSO BE OVER NORTHWEST IL THIS
EVENING PROVIDING ADDITIONAL LIFT. CAPE WILL BE LIMITED WITH
MODEL SOUNDINGS SHOWING SHALLOW AREAS OF CAPE AT 1000 J/KG OR LESS.
PWAT VALUES WILL BE AROUND 1.9 INCHES SO TORRENTIAL DOWNPOURS ARE
THE MOST LIKELY HAZARD.
SATURDAY...
THE PLAINS LOW/TROUGH MOVES OVER THE MIDWEST WITH SATURDAY
HAVING THE BEST CHANCE FOR SEVERE WEATHER ESPECIALLY SOUTH OF I-88.
PWAT VALUES REMAIN HIGH AROUND 1.8 INCHES IN THE MORNING AND THEN
INCREASE TO 2-2.3 INCHES SOUTH OF I-80 SATURDAY AFTERNOON. CAPE
VALUES WILL BE MUCH MORE HEALTHY IN THE 3000 J/KG RANGE ESPECIALLY
ALONG AND SOUTH OF THE I-80 CORRIDOR. EXPECTING STORMS TO FIRE
ALONG THE LOWS COLD FRONT SATURDAY AFTERNOON AND EVENING WITH THE
CHANCES OF SHOWERS AND STORMS INCREASING AS YOU HEAD SOUTH. SOME OF
THESE STORMS MAY BE SEVERE WITH TORRENTIAL DOWNPOURS. HAIL AND WIND
LOOK TO BE THE MAIN SEVERE THREATS.
SATURDAY WILL FEEL UNPLEASANT TO MANY WITH HIGHS IN THE UPPER 80S
AND HIGH DEWPOINTS. MAX HEAT INDICES WILL BE IN THE 90S...WITH MID
TO UPPER 90 HEAT INDICES EXPECTED SOUTH OF I-80.
SUNDAY...
THE LOW OVER CANADA DRIFTS SOUTHEAST MOVING OVER WISCONSIN SUNDAY.
ADDITIONAL THUNDERSTORMS ARE POSSIBLE NORTH OF THE I-80
CORRIDOR...WITH THE BEST CHANCES ALONG THE IL/WI STATE LINE. THE
STORMS PUSH EAST OF THE CWA IN THE EVENING. COOLER AIR ASSOCIATED
WITH THE LOW ALSO SPREAD SOUTH WITH HIGHS ON SUNDAY ONLY EXPECTED TO
GET INTO THE LOW TO MID 80S. OVERNIGHT LOWS WILL BE AROUND
60...EXCEPT FOR DOWNTOWN WHICH WILL BE IN THE LOW 60S.
MONDAY THROUGH THURSDAY...
WE REMAIN UNDER THE UPPER LEVEL TROUGH THROUGH NEXT WEEK WITH A
SURFACE HIGH MOVING OVER THE REGION BY MID WEEK. THERE ARE
OCCASIONAL CHANCES OF SHOWERS AND STORMS BUT NONE OF THOSE CHANCES
LOOK ALL THAT IMPRESSIVE AT THIS POINT. THE BIGGER STORY WILL BE
ANOTHER EXTENDED PERIOD OF BELOW NORMAL TEMPS...ALTHOUGH
TEMPERATURES WILL BE SLOWLY RISING THROUGH THE END OF THE FORECAST
PERIOD.
JEE
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 16Z...
* SOUTH WINDS GUSTING NEAR 20 KT AT TIMES INTO THIS AFTERNOON.
* SCATTERED LIGHT SHRA THROUGH EARLY AFTERNOON...WITH A BREAK
EXPECTED LATE AFTERNOON/EARLY EVENING.
* CHANCE OF TSRA...MAINLY TONIGHT.
RATZER
//DISCUSSION...UPDATED 16Z...
MID-LEVEL DISTURBANCE MOVING SOUTHEAST ACROSS SOUTHERN WI/NORTHERN
IL THROUGH MID-AFTERNOON WILL BRING POTENTIAL FOR SCATTERED
SHOWERS FROM VFR MID-DECK CIGS. TIMING OF MID-LEVEL CIRCULATION IN
RADAR APPROACHING KDLL SUGGESTS THIS FEATURE WILL PASS ACROSS
WESTERN LAKE MICHIGAN SHORE AROUND 21Z WITH A DECREASE IN SHRA
COVERAGE AFTER THAT TIME. IT APPEARS LITTLE THREAT OF THUNDER WILL
EXIST AT TERMINALS...WITH BETTER CHANCES REMAINING WEST AND FOCUSED
FROM EASTERN IOWA SOUTH ALONG THE MISSISSIPPI RIVER.
SURFACE PRESSURE FALLS ACROSS WI/NORTHERN IL AT 16Z IN ASSOCIATION
WITH ABOVE MENTIONED DISTURBANCE HELPING TO INCREASE WINDS AND
BACK THEM A BIT MORE SOUTHERLY 190-180 DEG. 1-MIN ASOS DATA
SHOWING SOME GUSTS ALREADY APPROACHING 20 KT AT ORD.
RATZER
PREVIOUS DISCUSSION FROM 12Z...
MOIST ADVECTION ALOFT ACROSS IA/NW IL/WI CONTINUES TO SPRING
SCATTERED SHOWERS WITH A FEW STORMS EARLY THIS MORNING. THE MAIN
DRIVING UPPER DISTURBANCE IS IN CENTRAL IA AND WILL CONTINUE TO
MOVE SOUTHEAST. IMMEDIATELY EAST OF THIS SHOULD BE THE MORE
WIDESPREAD SHOWER/STORM ACTIVITY...WITH ONLY ISOLATED/SCATTERED
FURTHER NORTHEAST NEAR THE CHICAGOLAND TAF SITES.
WHILE THE UPPER DISTURBANCE MOVES BEYOND THE AREA IN THE
AFTERNOON...THERE WILL STILL BE MOIST ADVECTION ALONG WITH THE
APPROACH OF A SURFACE TROUGH...SO CANNOT RULE OUT SOME SHRA/TSRA
ACTIVITY. HOWEVER OVERALL SUPPORT IS LOW AND THUS HAVE TAFS MAINLY
DRY IN THE AFTERNOON. THE MORE FAVORABLE CHANCES FOR PRECIP WILL
ARRIVE AFTER DARK AS THE NEXT UPPER DISTURBANCE MOVES ACROSS THE
AREA AND INTO A VERY MOIST ENVIRONMENT. CONTINUE TO MENTION
PROB30S FOR TSRA DURING THE MID/LATE EVE INTO EARLY OVERNIGHT.
SOME GUIDANCE DOES INDICATE MVFR CONDITIONS IN THE IMMEDIATE WAKE
OF THIS AND BELIEVE IF IT DOES RAIN WITH DIMINISHING FLOW LATE
TONIGHT THEN THERE COULD VERY WELL BE SOME LOWERED VISBYS/CIGS
INTO EARLY SATURDAY MORNING.
//ORD AND MDW CONFIDENCE...UPDATED 16Z...
* MEDIUM IN SHRA TRENDS. CIGS/VIS SHOULD REMAIN VFR.
* MEDIUM CONFIDENCE IN WIND TRENDS.
* LOW IN TSRA OCCURRING TONIGHT. MEDIUM IN TIMING IF IT WERE TO
OCCUR.
RATZER
//OUTLOOK FOR ORD/MDW FOR 00Z SUNDAY-12Z FRIDAY...UPDATED 12Z...
SATURDAY NIGHT...SMALL CHANCE OF TSRA.
SUNDAY...CHANCE OF TSRA.
MONDAY...VFR LIKELY. STRONG NORTH-NORTHEAST WINDS.
TUESDAY...VFR.
WEDNESDAY-THURSDAY...SLIGHT CHANCE OF TSRA.
MTF
&&
.MARINE...
228 AM CDT
SOUTHERLY FLOW WILL INCREASE OVER THE LAKE TODAY AS HIGH PRESSURE
SCOOTS EASTWARD FROM THE OHIO RIVER VALLEY. THE SURFACE TROUGH
LEADING TO THE INCREASE IN WINDS WILL ARRIVE EARLY
SATURDAY...HOWEVER WEAKEN TO THE POINT WHERE IT WILL NOT SHIFT THE
WINDS MUCH IF ANY FROM THE SOUTH-SOUTHWEST. THE LOW PRESSURE
DRIVING THIS TROUGH WILL EVOLVE OVER THE LAKE ON SUNDAY TURNING
WINDS NORTHERLY AND DRIVING A SHARP INCREASE IN SPEEDS SUNDAY
NIGHT AND PERSISTING INTO MONDAY. FOR JULY STANDARDS THESE WIND
SPEEDS ONCE AGAIN WILL BE QUITE STRONG WITH EVEN POSSIBLY SOME
GALE FORCE NORTHERLY GUSTS LATE SUNDAY NIGHT INTO MONDAY MORNING.
WITH ONCE AGAIN A LONG FETCH WAVES SHOULD REACH HEIGHTS OF OVER 6
FT OVER MUCH OF THE LAKE WITH EVEN POSSIBLY UP TO 10 FT AGAIN
ACROSS THE FAR SOUTH...PRIMARILY NEAR THE INDIANA SHORE.
MTF
&&
.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:
WWW.FACEBOOK.COM/US.NATIONALWEATHERSERVICE.CHICAGO.GOV
WWW.TWITTER.COM/NWSCHICAGO
WWW.YOUTUBE.COM/NWSCHICAGO
Area Forecast Discussion
National Weather Service Lincoln IL
1043 AM CDT Fri Jul 25 2014
.DISCUSSION...
ISSUED 1043 AM CDT Fri Jul 25 2014
Already did a major update to the forecast today for more cloud
cover along with much higher chances of showers along with
isolated thunderstorms for areas west of I-57 into early
afternoon. Continued a chance of showers and thunderstorms during
mid/late afternoon over central IL with just slight chances in
southeast IL while far southeast IL near Lawrence county to likely
stay dry today. Trimmed highs down a bit into upper 70s to around
80 degrees due to more showers and clouds over central IL.
MCS over eastern IA, northeast MO and nw half of IL has held
together longer than earlier expected as it tracked se to along
I-72 by late morning. Just isolated thunderstorms west of I-55
while more numerous thunderstorms and heavier rains have been on
western edge of MCS over ne MO and se IA. SPC has 5% risk of large
hail and damaging wind gusts nw of a Shelbville to Tuscola line
today so severe threat quite low today.
12Z ILX sounding showing a lot of dry air below 650 mb so this
should weaken the convection into this afternoon as it continues
moving se toward I-70. Think HRRR model is holding onto convection
too long as it moves it into southeast IL by mid afternoon. NAM
and RUC/RAP model on the other hand appears too quick diminishing
convection during early afternoon. Will blend between the wetter
HRRR and drier NAM/RUC models for the afternoon forecast.
Southerly winds increasing to 10-15 mph this afternoon between
1021 mb high pressure over WV and ridging into the ohio river
valley and 1006 mb low pressure in eastern SD/NE to bring in a bit
more humid air into central IL this afternoon. Dewpoints currently
in the upper 50s to around 60F rising to between 60-65F during the
afternoon and highest west of the IL river.
07
&&
.AVIATION...
ISSUED 657 AM CDT Fri Jul 25 2014
Mainly VFR conditions are expected over central and southeast
Illinois today and tonight. A weakening thunderstorm system will
move across central AZ today bringing increasing low and mid-
level cloud cover along with scattered showers and isolated
thunderstorms. The best chances for showers and thunderstorms
until 18Z will be from KSPI-KBMI northwestward. Have placed
temporary MVFR conditions in the KPIA TAF, but left out of other
area TAFS due to low probabilities and coverage of MVFR
cigs/vsbys. Another disturbance tracking into the area this
evening is expected to bring more showers and thunderstorms
overnight. Winds generally southerly around 10 KTS from 15Z through
12Z Saturday.
Onton
&&
.PREV DISCUSSION...
ISSUED 247 AM CDT Fri Jul 25 2014
Illinois remains on the periphery of high pressure centered over
Ohio early this morning. To our northwest, convection has been
ramping up quickly over the last couple hours in central and
northwest Iowa along a warm front, as the low level jet increases
from the central Plains. The initial concern for this forecast
package involves how much of this convection will affect our area
today. However, the main forecast issue is with severe weather
potential Saturday afternoon and evening.
SHORT TERM...Today through Saturday Night:
The track of this developing thunderstorm cluster has necessitated
some noticeable changes to the going forecast for today. Earlier
grids mainly had the north half affected by the overnight
convection. Latest high-res models are all indicating a
southeast track, which would favor the western parts of the CWA.
However, very dry conditions above 850 mb were observed on our
evening sounding, and LAPS soundings for Peoria and Springfield at
1 am still showed a sizable dry wedge around 800 mb. Model
soundings show this eroding somewhat by mid morning but not
completely going away, so eastward extent is still a bit in
question. Will have the highest PoP`s from around Rushville to
Jacksonville, with lower chances spreading eastward as far as
I-57. Rain chances should be diminishing during the afternoon as
the atmosphere becomes more capped.
Evening models in general agreement with a shortwave tracking
along the periphery of the upper ridge to our southwest, but
convective alignment is more variable. The general consensus is
for a convective complex to develop to our north by late evening.
The ECMWF and GEM track this southeast and just brush by the
forecast area, while the NAM and GFS show some development
extending southwest along a frontal boundary into Kansas. Have not
made much change here at this point, since leftover boundaries
from the daytime activity may also contribute and are not
adequately handled by the synoptic models.
The frontal boundary will likely hang up somewhere in the I-72
vicinity on Saturday. Have gone with only slight chance PoP`s
during the morning, then increased them to around 30-40% in the
afternoon as the cap starts to erode. Very unstable conditions
will be developing, as dew points rise into the mid 70s and yield
CAPE values well over 3000 J/kg. 0-6km shear around 35 knots is
progged by evening, when the best storm chances in our area are
likely. Latest SPC Day2 outlook shows 30% severe probabilities
over the entire forecast area, with damaging winds favored.
Precipitable waters rising to just over 2 inches will also result
in locally heavy rains, and the ECMWF and GFS indicate some
training echoes could also be a concern.
Some secondary concerns also exist on Saturday for heat advisory
potential. With dew points rising into the mid 70s, am expecting
heat index values of 100-102 over most areas except perhaps along
and north of I-74. This is just shy of the 105F criteria for this
area.
LONG TERM...Sunday through Thursday:
Any lingering rain on Sunday will likely be in the morning, before
a cold front passes. This will be ahead of an upper low, currently
entering southwest Saskatchewan, that will be opening up as it
drops southeast through the Great Lakes region. This will evolve
into a broad upper trough that will dominate the eastern U.S.
throughout the week, bringing another period of cooler conditions.
Monday is likely to be the coolest day, with highs mainly in the
mid 70s, and comfortable humidity levels to persist much of the
work week.
Geelhart
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS INDIANAPOLIS IN
217 PM EDT FRI JUL 25 2014
.UPDATE...
THE LONG TERM SECTION HAS BEEN UPDATED BELOW.
&&
.SYNOPSIS...
ISSUED AT 248 AM EDT FRI JUL 25 2014
DRY AND COMFORTABLE WEATHER WILL GIVE WAY TO WARM...HUMID AND
STORMY WEATHER THIS WEEKEND AS A COLD FRONT GRADUALLY DROPS
SOUTHEAST ACROSS THE AREA. SEVERE STORMS ARE A POSSIBILITY BY LATE
SATURDAY. MEANWHILE...AN UPPER WAVE WILL DROP SOUTHEAST ACROSS THE
LOWER GREAT LAKES SUNDAY NIGHT PUSHING THE FRONT TO THE SOUTHERN
STATES AND ALLOWING FOR MORE BELOW NORMAL TEMPERATURES NEXT WEEK.
&&
.NEAR TERM /REST OF TODAY/...
ISSUED AT 1036 AM EDT FRI JUL 25 2014
HIGH LEVEL CLOUD DEBRIS EXPANDING INTO THE REGION THIS MORNING
FROM ONGOING CONVECTION OVER THE MID MISSISSIPPI VALLEY. TEMPS
WERE MAINLY IN THE 60S AT 14Z.
CONVECTION ACROSS EASTERN IOWA AND WESTERN ILLINOIS EXPECTED TO
PROPAGATE SOUTHEAST ALONG THE MISSISSIPPI RIVER IN CLOSER
PROXIMITY TO THE WARM FRONT. CENTRAL INDIANA REMAINS UNDER THE
PROTECTION OF THE SLOWLY DEPARTING HIGH PRESSURE...WITH
MESOANALYSIS SHOWING PWATS STILL BELOW 1 INCH AND AN ABUNDANCE OF
DRY AIR BELOW 15KFT. AIRMASS WILL SLOWLY MOISTEN AS THE AFTERNOON
PROGRESSES AND THE WARM FRONT APPROACHES THE WABASH VALLEY.
HOWEVER...CURRENT HRRR LOOKS FAR TOO AGGRESSIVE IN SPREADING
PRECIP INTO THE REGION OVER THE NEXT 6 HOURS...ESPECIALLY
CONSIDERING THE AMBIENT AIRMASS. MID AND HIGH LEVEL CLOUDS WILL BE
THE PRIMARY IMPACT...LIMITING SUNSHINE AND TEMP RISES A BIT MORE
THAN EARLIER THOUGHT. HAVE THEREFORE BUMPED HIGHS DOWN A COUPLE
DEGREES AND INCREASED CLOUD COVERAGE THROUGH THE REMAINDER OF THE
DAY. ANY PRECIP IS LIKELY TO HOLD OFF IN FAR NORTHWEST COUNTIES
UNTIL EARLY EVENING WITH THE APPROACH OF THE FRONT.
ZONE AND GRID UPDATES OUT.
&&
.SHORT TERM /TONIGHT THROUGH SUNDAY NIGHT/...
ISSUED AT 248 AM EDT FRI JUL 25 2014
A CONVECTIVELY ACTIVE SHORT TERM WILL PROVIDE MANY CHALLENGES TO THE
FORECAST..NOT THE LEAST OF WHICH IS THE POTENTIAL FOR SEVERE WEATHER
AND HEAVY RAIN SATURDAY PM...ILLUSTRATED BY THE DAY2 SPC OUTLOOK.
MODELS ARE IN GOOD AGREEMENT THAT A SHARP UPPER TROUGH WILL DROP
SOUTHEAST ACROSS THE EASTERN GREAT LAKES AND OHIO ON SUNDAY NIGHT
WHICH WILL FORCE A STRONG COLD FRONT SOUTHEAST ACROSS THE FORECAST
AREA. THE FRONT WILL INTERACT WITH INCREASING MOISTURE AND
INSTABILITY AND RESULT IN THUNDERSTORM CHANCES STARTING FRIDAY NIGHT
AND CONTINUING THROUGH SUNDAY NIGHT. THE BEST CHANCES WILL BE
SATURDAY NIGHT AND SUNDAY MORNING AS A LOW LEVEL JET SETTLES ACROSS
SOUTH CENTRAL INDIANA RESULTING IN PRECIPITABLE WATER VALUES AROUND
2 INCHES THERE. IN ADDITION...UPPER JET WILL STRETCH OUT ACROSS THE
LOWER GREAT LAKES WITH EMBEDDED JET MAXIMA AIDING IN RAINFALL
EFFICIENCY AND SEVERE POTENTIAL. SO...WITH ABUNDANT
FORCING...INSTABILITY AND MOISTURE...POTENTIAL SEVERE MCS ACTIVITY
LOOKS LIKE A GOOD BET SATURDAY NIGHT WITH DAMAGING WINDS AND HEAVY
RAIN THE MAIN CONCERNS. IF THE ATMOSPHERE CAN RECOVER ENOUGH FROM
THE FRIDAY NIGHT AND SATURDAY NIGHT STORMS...COULD ALSO SEE A FEW
SEVERE STORMS DURING THE AFTERNOON AND EVENING HOURS SATURDAY AND
SUNDAY BEFORE THE COLD FRONT MOVES THROUGH SUNDAY NIGHT.
SIDED CLOSER TO THE COOLER 00Z NAM MOS FOR AFTERNOON HIGHS AS THE
00Z GFS AND JUL 24 00Z ECM LOOK TOO WARM BY SATURDAY CONSIDERING
CLOUD COVER AND EFFECT OF FRIDAY NIGHT AND SATURDAY MORNING
CONVECTION.
&&
.LONG TERM /MONDAY NIGHT THROUGH FRIDAY/...
ISSUED AT 216 PM EDT FRI JUL 25 2014
THE LONG TERM WILL START OUT DRY AND COOL WITH HIGH PRESSURE
BUILDING OVER THE AREA. WITH AN UPPER TROUGH OVER THE EASTERN U.S.
COOLER THAN NORMAL CONDITIONS WILL CONTINUE THROUGH THE LONG TERM
WITH TEMPERATURES SLOWLY WARMING BUT STILL NOT GETTING BACK UP TO
NORMAL. WEAK SHORTWAVES MOVING THROUGH THE MAIN NORTHWEST FLOW
PATTERN COULD BRING IN SMALL THUNDERSTORM CHANCES WEDNESDAY THROUGH
FRIDAY ESPECIALLY ACROSS THE NORTHERN COUNTIES. WITH A WIDE SPREAD
IN ENSEMBLE SOLUTIONS FOR THAT TIME WILL LEAVE THE ALLBLEND SLIGHT
TO LOW CHANCE POPS ALONE.
&&
.AVIATION /DISCUSSION FOR 251800Z TAF ISSUANCE/...
ISSUED AT 115 PM EDT FRI JUL 25 2014
CURRENTLY LOOKING VFR THROUGH THE PERIOD. LARGE AREA OF SHOWERS
AND THUNDERSTORMS OVER CENTRAL ILLINOIS THROUGH EASTERN MISSOURI
HAS BEEN WEAKENING AND CONTINUING TO HEAD TO THE SOUTHEAST. BASED
ON CURRENT MOTIONS AND LACK OF MOISTURE OVER INDIANA THINK THIS
TREND WILL CONTINUE...BUT COULD SEE A BRIEF PERIOD OF SHOWERS AT
KHUF SOMETIME AROUND 20Z OR SO. DON/T THINK THIS WILL IMPACT
FLIGHT CATEGORY. ELSEWHERE EXPECT INCREASING CLOUD COVER BUT WITH
VFR CEILINGS. AT KLAF MODELS ARE SHOWING POTENTIAL FOR SOME
THUNDERSTORMS DURING THE OVERNIGHT AND KEPT THESE AS A VCTS FROM
8-14Z WITH STILL A DECENT AMOUNT OF UNCERTAINTY ON EXACT LOCATION
AND TIMING. EXPECT TO SEE MORE WIDESPREAD STORMS OVER THE SITES
LATE SATURDAY NIGHT BUT AT THIS POINT THAT/S OUTSIDE OF THE TAF
PERIOD. WINDS SHOULD REMAIN 5-10 KTS DURING THE OVERNIGHT AND
THINK THIS SHOULD PRECLUDE ANY FOG DEVELOPMENT.
&&
.IND WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...MK
NEAR TERM...RYAN
SHORT TERM...MK
LONG TERM....CP
AVIATION...CP
VISIT US AT HTTP://WWW.WEATHER.GOV/IND
FOLLOW US ON FACEBOOK...TWITTER AND YOUTUBE AT:
WWW.FACEBOOK.COM/NWSINDIANAPOLIS
WWW.TWITTER.COM/NWSINDIANAPOLIS
WWW.YOUTUBE.COM/NWSINDIANAPOLIS
AREA FORECAST DISCUSSION
NWS INDIANAPOLIS IN
127 PM EDT FRI JUL 25 2014
.UPDATE...
THE AVIATION SECTION HAS BEEN UPDATED BELOW.
&&
.SYNOPSIS...
ISSUED AT 248 AM EDT FRI JUL 25 2014
DRY AND COMFORTABLE WEATHER WILL GIVE WAY TO WARM...HUMID AND
STORMY WEATHER THIS WEEKEND AS A COLD FRONT GRADUALLY DROPS
SOUTHEAST ACROSS THE AREA. SEVERE STORMS ARE A POSSIBILITY BY LATE
SATURDAY. MEANWHILE...AN UPPER WAVE WILL DROP SOUTHEAST ACROSS THE
LOWER GREAT LAKES SUNDAY NIGHT PUSHING THE FRONT TO THE SOUTHERN
STATES AND ALLOWING FOR MORE BELOW NORMAL TEMPERATURES NEXT WEEK.
&&
.NEAR TERM /REST OF TODAY/...
ISSUED AT 1036 AM EDT FRI JUL 25 2014
HIGH LEVEL CLOUD DEBRIS EXPANDING INTO THE REGION THIS MORNING
FROM ONGOING CONVECTION OVER THE MID MISSISSIPPI VALLEY. TEMPS
WERE MAINLY IN THE 60S AT 14Z.
CONVECTION ACROSS EASTERN IOWA AND WESTERN ILLINOIS EXPECTED TO
PROPAGATE SOUTHEAST ALONG THE MISSISSIPPI RIVER IN CLOSER
PROXIMITY TO THE WARM FRONT. CENTRAL INDIANA REMAINS UNDER THE
PROTECTION OF THE SLOWLY DEPARTING HIGH PRESSURE...WITH
MESOANALYSIS SHOWING PWATS STILL BELOW 1 INCH AND AN ABUNDANCE OF
DRY AIR BELOW 15KFT. AIRMASS WILL SLOWLY MOISTEN AS THE AFTERNOON
PROGRESSES AND THE WARM FRONT APPROACHES THE WABASH VALLEY.
HOWEVER...CURRENT HRRR LOOKS FAR TOO AGGRESSIVE IN SPREADING
PRECIP INTO THE REGION OVER THE NEXT 6 HOURS...ESPECIALLY
CONSIDERING THE AMBIENT AIRMASS. MID AND HIGH LEVEL CLOUDS WILL BE
THE PRIMARY IMPACT...LIMITING SUNSHINE AND TEMP RISES A BIT MORE
THAN EARLIER THOUGHT. HAVE THEREFORE BUMPED HIGHS DOWN A COUPLE
DEGREES AND INCREASED CLOUD COVERAGE THROUGH THE REMAINDER OF THE
DAY. ANY PRECIP IS LIKELY TO HOLD OFF IN FAR NORTHWEST COUNTIES
UNTIL EARLY EVENING WITH THE APPROACH OF THE FRONT.
ZONE AND GRID UPDATES OUT.
&&
.SHORT TERM /TONIGHT THROUGH SUNDAY NIGHT/...
ISSUED AT 248 AM EDT FRI JUL 25 2014
A CONVECTIVELY ACTIVE SHORT TERM WILL PROVIDE MANY CHALLENGES TO THE
FORECAST..NOT THE LEAST OF WHICH IS THE POTENTIAL FOR SEVERE WEATHER
AND HEAVY RAIN SATURDAY PM...ILLUSTRATED BY THE DAY2 SPC OUTLOOK.
MODELS ARE IN GOOD AGREEMENT THAT A SHARP UPPER TROUGH WILL DROP
SOUTHEAST ACROSS THE EASTERN GREAT LAKES AND OHIO ON SUNDAY NIGHT
WHICH WILL FORCE A STRONG COLD FRONT SOUTHEAST ACROSS THE FORECAST
AREA. THE FRONT WILL INTERACT WITH INCREASING MOISTURE AND
INSTABILITY AND RESULT IN THUNDERSTORM CHANCES STARTING FRIDAY NIGHT
AND CONTINUING THROUGH SUNDAY NIGHT. THE BEST CHANCES WILL BE
SATURDAY NIGHT AND SUNDAY MORNING AS A LOW LEVEL JET SETTLES ACROSS
SOUTH CENTRAL INDIANA RESULTING IN PRECIPITABLE WATER VALUES AROUND
2 INCHES THERE. IN ADDITION...UPPER JET WILL STRETCH OUT ACROSS THE
LOWER GREAT LAKES WITH EMBEDDED JET MAXIMA AIDING IN RAINFALL
EFFICIENCY AND SEVERE POTENTIAL. SO...WITH ABUNDANT
FORCING...INSTABILITY AND MOISTURE...POTENTIAL SEVERE MCS ACTIVITY
LOOKS LIKE A GOOD BET SATURDAY NIGHT WITH DAMAGING WINDS AND HEAVY
RAIN THE MAIN CONCERNS. IF THE ATMOSPHERE CAN RECOVER ENOUGH FROM
THE FRIDAY NIGHT AND SATURDAY NIGHT STORMS...COULD ALSO SEE A FEW
SEVERE STORMS DURING THE AFTERNOON AND EVENING HOURS SATURDAY AND
SUNDAY BEFORE THE COLD FRONT MOVES THROUGH SUNDAY NIGHT.
SIDED CLOSER TO THE COOLER 00Z NAM MOS FOR AFTERNOON HIGHS AS THE
00Z GFS AND JUL 24 00Z ECM LOOK TOO WARM BY SATURDAY CONSIDERING
CLOUD COVER AND EFFECT OF FRIDAY NIGHT AND SATURDAY MORNING
CONVECTION.
&&
.LONG TERM /MONDAY THROUGH THURSDAY NIGHT/...
ISSUED AT 340 AM EDT FRI JUL 25 2014
SCATTERED RAIN SHOWERS WILL BE POSSIBLE ACROSS CENTRAL INDIANA ON
MONDAY AS AN UPPER LEVEL TROUGH AND ASSOCIATED SURFACE COLD FRONT
DEPART THE AREA. AFTER THAT...HIGH PRESSURE WILL RESULT IN DRY
CONDITIONS THROUGH MID-WEEK. AT THAT POINT...MODELS BECOME
INCONSISTENT FOR THE END OF LONG TERM PERIOD. LATEST REGIONAL
INITIALIZATION IS PICKING UP ON AN UPPER TROUGH FOR THURSDAY...BUT
IS STRUGGLING WITH TIMING. DUE TO THE MODEL INCONSISTENCY...WILL
NOT DEVIATE FROM INITIALIZATION AT THIS TIME WHICH HAS PERIODS OF
SLIGHT CHANCE POPS FOR THURSDAY/THURSDAY NIGHT. TEMPS THROUGH THE
PERIOD WILL BE WELL BELOW NORMAL WITH HIGHS ONLY IN THE 70S AND
LOWS IN THE 50S. TEMPS WILL INCREASE SLIGHTLY BY THE END OF THE
PERIOD...BUT WILL STILL BE BELOW NORMAL.
&&
.AVIATION /DISCUSSION FOR 251800Z TAF ISSUANCE/...
ISSUED AT 115 PM EDT FRI JUL 25 2014
CURRENTLY LOOKING VFR THROUGH THE PERIOD. LARGE AREA OF SHOWERS
AND THUNDERSTORMS OVER CENTRAL ILLINOIS THROUGH EASTERN MISSOURI
HAS BEEN WEAKENING AND CONTINUING TO HEAD TO THE SOUTHEAST. BASED
ON CURRENT MOTIONS AND LACK OF MOISTURE OVER INDIANA THINK THIS
TREND WILL CONTINUE...BUT COULD SEE A BRIEF PERIOD OF SHOWERS AT
KHUF SOMETIME AROUND 20Z OR SO. DON/T THINK THIS WILL IMPACT
FLIGHT CATEGORY. ELSEWHERE EXPECT INCREASING CLOUD COVER BUT WITH
VFR CEILINGS. AT KLAF MODELS ARE SHOWING POTENTIAL FOR SOME
THUNDERSTORMS DURING THE OVERNIGHT AND KEPT THESE AS A VCTS FROM
8-14Z WITH STILL A DECENT AMOUNT OF UNCERTAINTY ON EXACT LOCATION
AND TIMING. EXPECT TO SEE MORE WIDESPREAD STORMS OVER THE SITES
LATE SATURDAY NIGHT BUT AT THIS POINT THAT/S OUTSIDE OF THE TAF
PERIOD. WINDS SHOULD REMAIN 5-10 KTS DURING THE OVERNIGHT AND
THINK THIS SHOULD PRECLUDE ANY FOG DEVELOPMENT.
&&
.IND WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...MK
NEAR TERM...RYAN
SHORT TERM...MK
LONG TERM....TDUD
AVIATION...CP
VISIT US AT HTTP://WWW.WEATHER.GOV/IND
FOLLOW US ON FACEBOOK...TWITTER AND YOUTUBE AT:
WWW.FACEBOOK.COM/NWSINDIANAPOLIS
WWW.TWITTER.COM/NWSINDIANAPOLIS
WWW.YOUTUBE.COM/NWSINDIANAPOLIS
AREA FORECAST DISCUSSION
NWS INDIANAPOLIS IN
1058 AM EDT FRI JUL 25 2014
.UPDATE...
THE AVIATION SECTION HAS BEEN UPDATED BELOW.
&&
.SYNOPSIS...
ISSUED AT 248 AM EDT FRI JUL 25 2014
DRY AND COMFORTABLE WEATHER WILL GIVE WAY TO WARM...HUMID AND
STORMY WEATHER THIS WEEKEND AS A COLD FRONT GRADUALLY DROPS
SOUTHEAST ACROSS THE AREA. SEVERE STORMS ARE A POSSIBILITY BY LATE
SATURDAY. MEANWHILE...AN UPPER WAVE WILL DROP SOUTHEAST ACROSS THE
LOWER GREAT LAKES SUNDAY NIGHT PUSHING THE FRONT TO THE SOUTHERN
STATES AND ALLOWING FOR MORE BELOW NORMAL TEMPERATURES NEXT WEEK.
&&
.NEAR TERM /REST OF TODAY/...
ISSUED AT 1036 AM EDT FRI JUL 25 2014
HIGH LEVEL CLOUD DEBRIS EXPANDING INTO THE REGION THIS MORNING
FROM ONGOING CONVECTION OVER THE MID MISSISSIPPI VALLEY. TEMPS
WERE MAINLY IN THE 60S AT 14Z.
CONVECTION ACROSS EASTERN IOWA AND WESTERN ILLINOIS EXPECTED TO
PROPAGATE SOUTHEAST ALONG THE MISSISSIPPI RIVER IN CLOSER
PROXIMITY TO THE WARM FRONT. CENTRAL INDIANA REMAINS UNDER THE
PROTECTION OF THE SLOWLY DEPARTING HIGH PRESSURE...WITH
MESOANALYSIS SHOWING PWATS STILL BELOW 1 INCH AND AN ABUNDANCE OF
DRY AIR BELOW 15KFT. AIRMASS WILL SLOWLY MOISTEN AS THE AFTERNOON
PROGRESSES AND THE WARM FRONT APPROACHES THE WABASH VALLEY.
HOWEVER...CURRENT HRRR LOOKS FAR TOO AGGRESSIVE IN SPREADING
PRECIP INTO THE REGION OVER THE NEXT 6 HOURS...ESPECIALLY
CONSIDERING THE AMBIENT AIRMASS. MID AND HIGH LEVEL CLOUDS WILL BE
THE PRIMARY IMPACT...LIMITING SUNSHINE AND TEMP RISES A BIT MORE
THAN EARLIER THOUGHT. HAVE THEREFORE BUMPED HIGHS DOWN A COUPLE
DEGREES AND INCREASED CLOUD COVERAGE THROUGH THE REMAINDER OF THE
DAY. ANY PRECIP IS LIKELY TO HOLD OFF IN FAR NORTHWEST COUNTIES
UNTIL EARLY EVENING WITH THE APPROACH OF THE FRONT.
ZONE AND GRID UPDATES OUT.
&&
.SHORT TERM /TONIGHT THROUGH SUNDAY NIGHT/...
ISSUED AT 248 AM EDT FRI JUL 25 2014
A CONVECTIVELY ACTIVE SHORT TERM WILL PROVIDE MANY CHALLENGES TO THE
FORECAST..NOT THE LEAST OF WHICH IS THE POTENTIAL FOR SEVERE WEATHER
AND HEAVY RAIN SATURDAY PM...ILLUSTRATED BY THE DAY2 SPC OUTLOOK.
MODELS ARE IN GOOD AGREEMENT THAT A SHARP UPPER TROUGH WILL DROP
SOUTHEAST ACROSS THE EASTERN GREAT LAKES AND OHIO ON SUNDAY NIGHT
WHICH WILL FORCE A STRONG COLD FRONT SOUTHEAST ACROSS THE FORECAST
AREA. THE FRONT WILL INTERACT WITH INCREASING MOISTURE AND
INSTABILITY AND RESULT IN THUNDERSTORM CHANCES STARTING FRIDAY NIGHT
AND CONTINUING THROUGH SUNDAY NIGHT. THE BEST CHANCES WILL BE
SATURDAY NIGHT AND SUNDAY MORNING AS A LOW LEVEL JET SETTLES ACROSS
SOUTH CENTRAL INDIANA RESULTING IN PRECIPITABLE WATER VALUES AROUND
2 INCHES THERE. IN ADDITION...UPPER JET WILL STRETCH OUT ACROSS THE
LOWER GREAT LAKES WITH EMBEDDED JET MAXIMA AIDING IN RAINFALL
EFFICIENCY AND SEVERE POTENTIAL. SO...WITH ABUNDANT
FORCING...INSTABILITY AND MOISTURE...POTENTIAL SEVERE MCS ACTIVITY
LOOKS LIKE A GOOD BET SATURDAY NIGHT WITH DAMAGING WINDS AND HEAVY
RAIN THE MAIN CONCERNS. IF THE ATMOSPHERE CAN RECOVER ENOUGH FROM
THE FRIDAY NIGHT AND SATURDAY NIGHT STORMS...COULD ALSO SEE A FEW
SEVERE STORMS DURING THE AFTERNOON AND EVENING HOURS SATURDAY AND
SUNDAY BEFORE THE COLD FRONT MOVES THROUGH SUNDAY NIGHT.
SIDED CLOSER TO THE COOLER 00Z NAM MOS FOR AFTERNOON HIGHS AS THE
00Z GFS AND JUL 24 00Z ECM LOOK TOO WARM BY SATURDAY CONSIDERING
CLOUD COVER AND EFFECT OF FRIDAY NIGHT AND SATURDAY MORNING
CONVECTION.
&&
.LONG TERM /MONDAY THROUGH THURSDAY NIGHT/...
ISSUED AT 340 AM EDT FRI JUL 25 2014
SCATTERED RAIN SHOWERS WILL BE POSSIBLE ACROSS CENTRAL INDIANA ON
MONDAY AS AN UPPER LEVEL TROUGH AND ASSOCIATED SURFACE COLD FRONT
DEPART THE AREA. AFTER THAT...HIGH PRESSURE WILL RESULT IN DRY
CONDITIONS THROUGH MID-WEEK. AT THAT POINT...MODELS BECOME
INCONSISTENT FOR THE END OF LONG TERM PERIOD. LATEST REGIONAL
INITIALIZATION IS PICKING UP ON AN UPPER TROUGH FOR THURSDAY...BUT
IS STRUGGLING WITH TIMING. DUE TO THE MODEL INCONSISTENCY...WILL
NOT DEVIATE FROM INITIALIZATION AT THIS TIME WHICH HAS PERIODS OF
SLIGHT CHANCE POPS FOR THURSDAY/THURSDAY NIGHT. TEMPS THROUGH THE
PERIOD WILL BE WELL BELOW NORMAL WITH HIGHS ONLY IN THE 70S AND
LOWS IN THE 50S. TEMPS WILL INCREASE SLIGHTLY BY THE END OF THE
PERIOD...BUT WILL STILL BE BELOW NORMAL.
&&
.AVIATION /DISCUSSION FOR THE 25/1500Z TAF ISSUANCE/...
ISSUED AT 1058 AM EDT FRI JUL 25 2014
TWEAKED CURRENT CONDITIONS ONLY. PREVIOUS DISCUSSION FOLLOWS...
MID CLOUDS WILL INCREASE THROUGHOUT THE TAF PERIOD AS A WARM FRONT
APPROACHES CENTRAL INDIANA TODAY...BUT VFR WILL PREVAIL. AT THIS
TIME...CONFIDENCE IS ONLY HIGH ENOUGH TO INTRODUCE VCTS AT KLAF FOR
TONIGHT. ELSEWHERE...CHANCES COULD IMPROVE AFTER SAT 12Z AS WARM
FRONT MOVES CLOSER. WINDS WILL BE SOUTHWESTERLY AT 3 TO 7 KTS. WINDS
WILL INCREASE AT KIND AROUND MID-MORNING TOMORROW WITH SUSTAINED
SPEEDS OF 12 TO 14 KTS AND GUSTS UP TO 20 KTS.
&&
.IND WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
SYNOPSIS...MK
NEAR TERM...RYAN
SHORT TERM...MK
LONG TERM....TDUD
AVIATION...TDUD/CP
VISIT US AT HTTP://WWW.WEATHER.GOV/IND
FOLLOW US ON FACEBOOK...TWITTER AND YOUTUBE AT:
WWW.FACEBOOK.COM/NWSINDIANAPOLIS
WWW.TWITTER.COM/NWSINDIANAPOLIS
WWW.YOUTUBE.COM/NWSINDIANAPOLIS
AREA FORECAST DISCUSSION
NWS INDIANAPOLIS IN
1036 AM EDT FRI JUL 25 2014
.UPDATE...
THE NEAR TERM SECTION HAS BEEN UPDATED BELOW.
&&
.SYNOPSIS...
ISSUED AT 248 AM EDT FRI JUL 25 2014
DRY AND COMFORTABLE WEATHER WILL GIVE WAY TO WARM...HUMID AND
STORMY WEATHER THIS WEEKEND AS A COLD FRONT GRADUALLY DROPS
SOUTHEAST ACROSS THE AREA. SEVERE STORMS ARE A POSSIBILITY BY LATE
SATURDAY. MEANWHILE...AN UPPER WAVE WILL DROP SOUTHEAST ACROSS THE
LOWER GREAT LAKES SUNDAY NIGHT PUSHING THE FRONT TO THE SOUTHERN
STATES AND ALLOWING FOR MORE BELOW NORMAL TEMPERATURES NEXT WEEK.
&&
.NEAR TERM /REST OF TODAY/...
ISSUED AT 1036 AM EDT FRI JUL 25 2014
HIGH LEVEL CLOUD DEBRIS EXPANDING INTO THE REGION THIS MORNING
FROM ONGOING CONVECTION OVER THE MID MISSISSIPPI VALLEY. TEMPS
WERE MAINLY IN THE 60S AT 14Z.
CONVECTION ACROSS EASTERN IOWA AND WESTERN ILLINOIS EXPECTED TO
PROPAGATE SOUTHEAST ALONG THE MISSISSIPPI RIVER IN CLOSER
PROXIMITY TO THE WARM FRONT. CENTRAL INDIANA REMAINS UNDER THE
PROTECTION OF THE SLOWLY DEPARTING HIGH PRESSURE...WITH
MESOANALYSIS SHOWING PWATS STILL BELOW 1 INCH AND AN ABUNDANCE OF
DRY AIR BELOW 15KFT. AIRMASS WILL SLOWLY MOISTEN AS THE AFTERNOON
PROGRESSES AND THE WARM FRONT APPROACHES THE WABASH VALLEY.
HOWEVER...CURRENT HRRR LOOKS FAR TOO AGGRESSIVE IN SPREADING
PRECIP INTO THE REGION OVER THE NEXT 6 HOURS...ESPECIALLY
CONSIDERING THE AMBIENT AIRMASS. MID AND HIGH LEVEL CLOUDS WILL BE
THE PRIMARY IMPACT...LIMITING SUNSHINE AND TEMP RISES A BIT MORE
THAN EARLIER THOUGHT. HAVE THEREFORE BUMPED HIGHS DOWN A COUPLE
DEGREES AND INCREASED CLOUD COVERAGE THROUGH THE REMAINDER OF THE
DAY. ANY PRECIP IS LIKELY TO HOLD OFF IN FAR NORTHWEST COUNTIES
UNTIL EARLY EVENING WITH THE APPROACH OF THE FRONT.
ZONE AND GRID UPDATES OUT.
&&
.SHORT TERM /TONIGHT THROUGH SUNDAY NIGHT/...
ISSUED AT 248 AM EDT FRI JUL 25 2014
A CONVECTIVELY ACTIVE SHORT TERM WILL PROVIDE MANY CHALLENGES TO THE
FORECAST..NOT THE LEAST OF WHICH IS THE POTENTIAL FOR SEVERE WEATHER
AND HEAVY RAIN SATURDAY PM...ILLUSTRATED BY THE DAY2 SPC OUTLOOK.
MODELS ARE IN GOOD AGREEMENT THAT A SHARP UPPER TROUGH WILL DROP
SOUTHEAST ACROSS THE EASTERN GREAT LAKES AND OHIO ON SUNDAY NIGHT
WHICH WILL FORCE A STRONG COLD FRONT SOUTHEAST ACROSS THE FORECAST
AREA. THE FRONT WILL INTERACT WITH INCREASING MOISTURE AND
INSTABILITY AND RESULT IN THUNDERSTORM CHANCES STARTING FRIDAY NIGHT
AND CONTINUING THROUGH SUNDAY NIGHT. THE BEST CHANCES WILL BE
SATURDAY NIGHT AND SUNDAY MORNING AS A LOW LEVEL JET SETTLES ACROSS
SOUTH CENTRAL INDIANA RESULTING IN PRECIPITABLE WATER VALUES AROUND
2 INCHES THERE. IN ADDITION...UPPER JET WILL STRETCH OUT ACROSS THE
LOWER GREAT LAKES WITH EMBEDDED JET MAXIMA AIDING IN RAINFALL
EFFICIENCY AND SEVERE POTENTIAL. SO...WITH ABUNDANT
FORCING...INSTABILITY AND MOISTURE...POTENTIAL SEVERE MCS ACTIVITY
LOOKS LIKE A GOOD BET SATURDAY NIGHT WITH DAMAGING WINDS AND HEAVY
RAIN THE MAIN CONCERNS. IF THE ATMOSPHERE CAN RECOVER ENOUGH FROM
THE FRIDAY NIGHT AND SATURDAY NIGHT STORMS...COULD ALSO SEE A FEW
SEVERE STORMS DURING THE AFTERNOON AND EVENING HOURS SATURDAY AND
SUNDAY BEFORE THE COLD FRONT MOVES THROUGH SUNDAY NIGHT.
SIDED CLOSER TO THE COOLER 00Z NAM MOS FOR AFTERNOON HIGHS AS THE
00Z GFS AND JUL 24 00Z ECM LOOK TOO WARM BY SATURDAY CONSIDERING
CLOUD COVER AND EFFECT OF FRIDAY NIGHT AND SATURDAY MORNING
CONVECTION.
&&
.LONG TERM /MONDAY THROUGH THURSDAY NIGHT/...
ISSUED AT 340 AM EDT FRI JUL 25 2014
SCATTERED RAIN SHOWERS WILL BE POSSIBLE ACROSS CENTRAL INDIANA ON
MONDAY AS AN UPPER LEVEL TROUGH AND ASSOCIATED SURFACE COLD FRONT
DEPART THE AREA. AFTER THAT...HIGH PRESSURE WILL RESULT IN DRY
CONDITIONS THROUGH MID-WEEK. AT THAT POINT...MODELS BECOME
INCONSISTENT FOR THE END OF LONG TERM PERIOD. LATEST REGIONAL
INITIALIZATION IS PICKING UP ON AN UPPER TROUGH FOR THURSDAY...BUT
IS STRUGGLING WITH TIMING. DUE TO THE MODEL INCONSISTENCY...WILL
NOT DEVIATE FROM INITIALIZATION AT THIS TIME WHICH HAS PERIODS OF
SLIGHT CHANCE POPS FOR THURSDAY/THURSDAY NIGHT. TEMPS THROUGH THE
PERIOD WILL BE WELL BELOW NORMAL WITH HIGHS ONLY IN THE 70S AND
LOWS IN THE 50S. TEMPS WILL INCREASE SLIGHTLY BY THE END OF THE
PERIOD...BUT WILL STILL BE BELOW NORMAL.
&&
.AVIATION /DISCUSSION FOR THE 25/1200Z TAF ISSUANCE/...
ISSUED AT 728 AM EDT FRI JUL 25 2014
THE FEW HOURS OF IFR CONDITIONS AT OUTLYING SITES EARLY THIS MORNING
HAVE ENDED...AND VFR CONDITIONS SHOULD NOW CONTINUE TO HOLD
STEADY. MID CLOUDS WILL INCREASE THROUGHOUT THE TAF PERIOD AS A
WARM FRONT APPROACHES CENTRAL INDIANA TODAY...BUT VFR WILL PREVAIL.
AT THIS TIME...CONFIDENCE IS ONLY HIGH ENOUGH TO INTRODUCE VCTS AT
KLAF FOR TONIGHT. ELSEWHERE...CHANCES COULD IMPROVE AFTER SAT 12Z
AS WARM FRONT MOVES CLOSER. WINDS WILL BE SOUTHWESTERLY AT 3 TO 7
KTS. WINDS WILL INCREASE AT KIND AROUND MID-MORNING TOMORROW WITH
SUSTAINED SPEEDS OF 12 TO 14 KTS AND GUSTS UP TO 20 KTS.
&&
.IND WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
SYNOPSIS...MK
NEAR TERM...RYAN
SHORT TERM...MK
LONG TERM....TDUD
AVIATION...TDUD
VISIT US AT HTTP://WWW.WEATHER.GOV/IND
FOLLOW US ON FACEBOOK...TWITTER AND YOUTUBE AT:
WWW.FACEBOOK.COM/NWSINDIANAPOLIS
WWW.TWITTER.COM/NWSINDIANAPOLIS
WWW.YOUTUBE.COM/NWSINDIANAPOLIS
AREA FORECAST DISCUSSION
NWS QUAD CITIES IA IL
727 PM CDT SAT JUL 26 2014
.UPDATE...
ISSUED AT 718 PM CDT SAT JUL 26 2014
HAVE UPDATED POPS TO TRIM THEM BACK CONSIDERABLY. MOISTURE AND
INSTABILITY REMAIN FAVORABLE FOR CONVECTION...BUT THERE IS A
CURRENT LACK OF A FOCUS FOR LIFT...SUCH AS STRONG MOISTURE
CONVERGENCE...TO OVERCOME LINGERING WARM AIR ALOFT. DID NOT FEEL
COMFORTABLE COMPLETELY DOING AWAY WITH POPS. THERE MAY BE SOME
POTENTIAL FOR SCATTERED STORMS LATE...AS THE MAIN BOUNDARY PUSHES
SOUTHEAST INTO THE AREA. SOME SHORT RANGE MODELS ARE SUGGESTING
DEVELOPMENT LATE...INCLUDING THE 13KM RAP AND THE HI-RES NMM/ARW RUNS.
&&
.SYNOPSIS...
ISSUED AT 314 PM CDT SAT JUL 26 2014
12Z UA ANALYSIS HAS A LLJ RUNNING FROM THE WESTERN PLAINS INTO THE
LOWER MISSOURI VALLEY. A POOL OF DEEP MOISTURE WAS ACROSS EASTERN
IOWA AND ILLINOIS WITH A SECONDARY FEED OF DEEP MOISTURE FROM THE
BIG BEND IN TEXAS INTO THE CENTRAL PLAINS. SATELLITE/RADAR TRENDS
THROUGH MID AFTERNOON SHOW PLENTY OF LOW CLOUDS ACROSS THE AREA WITH
NEW CONVECTION FROM NORTHERN MISSOURI INTO WESTERN ILLINOIS.
18Z SFC ANALYSIS HAS SEVERAL WEAK LOWS FROM NEAR KFSD INTO NORTHERN
KANSAS. A FRONTAL BOUNDARY RAN FROM A LOW NEAR KCNK ACROSS NORTHERN
MISSOURI AND INTO CENTRAL ILLINOIS. A COLD POOL FROM A DECAYING
THUNDERSTORM COMPLEX WAS ACROSS NORTHWEST IOWA. SEVERAL OTHER WEAK
BOUNDARIES WERE ACROSS CENTRAL IOWA AND NORTHERN ILLINOIS. DEW
POINTS WERE IN THE 60S ACROSS THE MIDWEST WITH 70 DEW POINTS FROM
THE GULF COAST INTO THE MID MISSISSIPPI VALLEY.
&&
.SHORT TERM...(THIS EVENING THROUGH SUNDAY)
ISSUED AT 314 PM CDT SAT JUL 26 2014
THE EVOLUTION OF CONVECTION THIS AFTERNOON IS IN QUESTION. THE LOW
CLOUDS HAVE PERSISTED LONGER THAN THOUGHT...AND...NEW DEVELOPMENT
HAS OCCURRED DURING THE DAY. SAID CLOUDS HAVE SUPPRESSED
TEMPERATURES AND LIMITED THE AMOUNT OF HEATING.
12Z AND 18Z SOUNDINGS CONTINUE TO SHOW PLENTY OF WARM AIR ALOFT
WHICH IS HELPING TO SUPPRESS CONVECTION. THE EXCEPTION IS ALONG THE
BOUNDARY FROM NORTHERN MISSOURI INTO WESTERN ILLINOIS. DIFFERENTIAL
HEATING SOUTH OF THE BOUNDARY COMBINED WITH A DISTURBANCE ALOFT HAS
ALLOWED CONVECTION TO DEVELOP THERE.
THROUGH LATE AFTERNOON LIMITED IF ANY CONVECTION IS EXPECTED ACROSS
THE NORTHERN HALF OF THE AREA. THE SOUTH THIRD OF THE AREA WILL SEE
CONVECTION PERSIST WITH SOME DEVELOPMENT POSSIBLE UP TO I-80.
THIS EVENING ISOLATED CONVECTION MAY BE POSSIBLE ACROSS THE NORTHERN
HALF OF THE AREA AS A WEAK DISTURBANCE MOVE THROUGH. IF FORCING CAN
INCREASE THE CONVECTION ACROSS THE SOUTH HALF MAY GROW UPSCALE INTO
A THUNDERSTORM COMPLEX THAT MOVES INTO CENTRAL AND EASTERN ILLINOIS
BY LATE EVENING.
AFTER MIDNIGHT ANY LINGERING CONVECTION ACROSS THE AREA WILL SLOWLY
DISSIPATE AS THE MAIN COLD FRONT MOVES THROUGH THE REGION.
DRY CONDITIONS WILL BE SEEN ACROSS THE AREA SUNDAY MORNING. BREEZY
CONDITIONS WILL DEVELOP DURING THE MID TO LATE MORNING HOURS AS
WINDS INCREASE.
SUNDAY AFTERNOON A WEAK DISTURBANCE WILL MOVE SOUTHEAST FROM
MINNESOTA INTO NORTHEAST ILLINOIS. MOISTURE IS LIMITED BUT THE COLD
AIR ALOFT AND FORCING SHOULD BE SUFFICIENT TO ALLOW SHOWERS AND A
FEW THUNDERSTORMS TO DEVELOP.
.LONG TERM...(SUNDAY NIGHT THROUGH SATURDAY)
ISSUED AT 314 PM CDT SAT JUL 26 2014
MONDAY NIGHT THROUGH THURSDAY...MEDIUM RANGE MODELS ARE IN GOOD
AGREEMENT WITH DEVELOPING A HIGH AMPLITUDE RIDGE OVER THE WESTERN US
WITH A DEEP TROUGH OVER THE EASTERN PART OF THE COUNTRY. THIS UPPER
AIR PATTERN WILL PRODUCE A NORTHWEST FLOW ALOFT AND BUILD SURFACE
HIGH PRESSURE OVER THE UPPER MISSISSIPPI VALLEY. ON MONDAY EVENING
WINDS WILL BE FROM THE NORTHWEST AND GUSTY AS HIGH PRESSURE MOVES
INTO REGION. PLEASANT CONDITIONS WILL FOLLOW NEXT WEEK WITH LOW
HUMIDITY AND BELOW NORMAL TEMPERATURES. HIGHS WILL BE IN THE UPPER
70S TO AROUND 80 WITH OVERNIGHT LOWS IN THE UPPER 50S AND LOWER 60S..
FRIDAY AND SATURDAY...LONG RANGE MODELS INDICATE THERE COULD BE
SHOWERS OR THUNDERSTORMS LATE NEXT WEEK AS A UPPER LEVEL SHORTWAVE
MOVES THROUGH THE NORTHWEST FLOW ALOFT.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z SUNDAY EVENING)
ISSUED AT 718 PM CDT SAT JUL 26 2014
THE OVERALL THUNDERSTORM THREAT HAS DIMINISHED EARLY THIS EVENING.
SOME ADDITIONAL SCATTERED STORMS WILL BE POSSIBLE...ESPECIALLY
LATE TONIGHT...BUT PREDICTABILITY TOO LOW TO INCLUDE IN TAFS AT
THIS TIME. RAIN EARLIER TODAY STAYED SOUTH OF ALL TAF SITES...SO
CONFIDENCE IS LOWER REGARDING EARLY MORNING MVFR FOG. HAVE OPTED
TO LEAVE OUT OF TAFS AND RE-EVALUATE THROUGH LATE EVENING.
&&
.DVN WATCHES/WARNINGS/ADVISORIES...
IA...NONE.
IL...NONE.
MO...NONE.
&&
$$
UPDATE...RP KINNEY
SYNOPSIS...08
SHORT TERM...08
LONG TERM...KUHL
AVIATION...RP KINNEY
AREA FORECAST DISCUSSION
NWS QUAD CITIES IA IL
1244 PM CDT FRI JUL 25 2014
.UPDATE...
ISSUED AT 1239 PM CDT FRI JUL 25 2014
THE NOCTURNAL THUNDERSTORM COMPLEX HAS ESSENTIALLY MOVED EAST OF
THE AREA. A COMBINATION OF DIFFERENTIAL HEATING AND RESIDUAL
BOUNDARIES HAVE ALLOWED ISOLATED TO SCATTERED CONVECTION TO
DEVELOP BEHIND THE DEPARTING COMPLEX.
FOR THE AFTERNOON SKIES WILL SLOWLY CLEAR ALLOWING TEMPERATURES TO
CLIMB. THE POSSIBILITY DOES EXIST OF SOME ISOLATED LATE AFTERNOON
AND EVENING CONVECTION.
UPDATE ISSUED AT 1041 AM CDT FRI JUL 25 2014
THE CURRENT THUNDERSTORM COMPLEX CONTINUES TO SLOWLY DECAY AS IT
MOVES EAST OF THE MISSISSIPPI. A MESO HIGH OVER NORTHEAST IOWA IS
STARTING TO COLLAPSE WHICH IS CAUSING A PERIOD OF STRONG WINDS ON
THE BACK SIDE OF THE PRECIPITATION.
NEW CONVECTION HAS DEVELOPED ACROSS NORTHERN IOWA WHICH APPEARS TO
BE ASSOCIATED WITH A WEAK THETA E GRADIENT. RECENT RADAR TRENDS
SHOW SOME WEAKENING OF THIS CONVECTION.
THE RAIN WILL END FROM WEST TO EAST THROUGH MID DAY AS WARMER
TEMPERATURES BUILDS IN ALOFT. THE POTENTIAL FOR CONVECTION WILL
HAVE TO BE RE-EVALUATED FOR THE AFTERNOON HOURS.
UPDATE ISSUED AT 700 AM CDT FRI JUL 25 2014
MCS OVER THE DVN CWA EARLY THIS MORNING WITH LOCALLY HEAVY RAINFALL
IN THE SOME OF THE STRONGER STORMS. IR SATELLITE SHOWED WARMING
TOPS IN OUR NORTHERN CWA WHICH ALSO IS INDICATED ON DOPPLER RADAR
WITH A WEAKENING TREND. THE ENTIRE MCS WILL GRADUALLY WEAKEN AS IT
PUSHES SOUTHEAST THIS MORNING AND THE HRRR MESO MODEL SHOWS THE BACK
EDGE OF THE MCS EXITING OUR SE CWA BY 1 PM. MANY AREAS SHOULD PICK
UP 1/4 TO 1/2 INCH OF RAIN WITH ISOLATED 1 INCH POSSIBLE.
&&
.SYNOPSIS...
ISSUED AT 345 AM CDT FRI JUL 25 2014
ELEVATED CONVECTION HAS FIRED IN THE PAST FEW HOURS ACROSS PORTIONS
OF NORTHERN/CENTRAL IA AND INTO WESTERN/SOUTHERN MN. THIS IS OCCURRING
ON THE NOSE OF A 50+ KNOT LOW LEVEL JET ON THE EASTERN EDGE OF A CAPPED
ELEVATED MIXED LAYER. SPC MESO ANALYSIS SHOWS THE BETTER MOISTURE
TRANSPORT IS STILL WEST OF THE DVN CWA WITH THE HIGHEST BULK SHEAR
VALUES IN SOUTHERN MN. PRECIPITABLE WATERS RANGE FROM 2.10 INCHES
IN WESTERN IA TO LESS THAN AN INCH IN NORTHERN IL. IR SATELLITE
LOOPS INDICATE TOPS CONTINUE TO RAPIDLY COOL AS THE THUNDERSTORM
ACTIVITY MOVES SOUTHEAST. A SHORT WAVE TROUGH WAS ALSO LIFTING
EASTWARD ACROSS THE NORTHERN/CENTRAL PLAINS AROUND A CLOSED UPPER
LOW IN SOUTHERN ALBERTA.
A COOL/STABLE SURFACE LAYER WAS NOTED ACROSS THE DVN CWA WITH 3 AM
TEMPERATURES IN THE MID 50S TO MID 60S...WHILE READINGS WERE WELL
INTO THE 70S TO LOWER 80S IN THE CENTRAL/SOUTHERN PLAINS.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 345 AM CDT FRI JUL 25 2014
FORECAST FOCUS ON THUNDERSTORMS MAINLY THIS MORNING AND TEMPERATURES.
TODAY...FORCING AND RAPIDLY INCREASING MOISTURE WILL ALLOW THUNDERSTORMS
TO CONTINUE TO DEVELOP/SPREAD ACROSS MUCH OF THE CWA THIS MORNING ON
THE NOSE OF THE STRONG LOW LEVEL JET...AS IT VEERS INTO THE AREA. DUE
TO THE ELEVATED NATURE OF THE STORMS AND THE COOL/STABLE SURFACE ENVIRONMENT
SEVERE WEATHER IS NOT EXPECTED. FREEZING LEVELS ARE QUITE HIGH AT NEARLY
15K FT. HOWEVER...SOME OF THE STRONGER STORMS MAY PRODUCE FREQUENT LIGHTNING...
SUB-SEVERE HAIL AND LOCALLY HEAVY RAINFALL. LATER THIS MORNING THE LOW
LEVEL JET WILL WEAKEN CONSIDERABLY ALONG WITH THE PASSAGE OF THE SHORT
WAVE TROUGH. A STRENGTHENING CAP WILL ALSO SPREAD EASTWARD INTO THE
CWA. THIS WILL DIMINISH OR END THE THUNDERSTORM ACTIVITY BY AFTERNOON
SO WILL HAVE LIKELY TO CATEGORICAL POPS THIS MORNING AND ONLY SMALL
POPS THIS AFTERNOON. EXPECTING EXTENSIVE CLOUD COVER TO LINGER INTO
THE AFTERNOON ESPECIALLY IN OUR EAST WHILE MORE SUNSHINE DEVELOPS IN
OUR WEST. MODELS REALLY SURGE THE WARM 850 MB TEMPERATURES INTO OUR
WESTERN CWA WITH +20C NOTED LATER IN THE AFTERNOON. I WILL FORECAST
MAXIMUM TEMPERATURES RANGING FROM THE MID 80S SW TO THE MID 70S NE.
HOWEVER...DEPENDING ON AMOUNT OF LINGERING CLOUDS (OR LACK OF) THIS
AFTERNOON THESE READINGS MAY NEED TO BE RE-VISITED.
TONIGHT...STRONG CAPPING ENVIRONMENT OVERSPREADS THE CWA EXCEPT
POSSIBLY OUR FAR EASTERN CWA. MODELS INSIST ON DEVELOPING CONVECTION
IN OUR EASTERN CWA AS THE LOW LEVEL JET STRENGTHENS AGAIN...BUT THERE
IS THE POTENTIAL THE STORMS MAY END UP FIRING EAST OF THE DVN CWA.
WILL HAVE CHANCE POPS TO COVER THIS SCENARIO BUT CONFIDENCE IS RATHER
LOW AT THIS POINT. THIS WILL BE A WARMER NIGHT WITH MINIMUM TEMPERATURES
IN THE MID 60S TO LOWER 70S.
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 345 AM CDT FRI JUL 25 2014
CHANCES FOR SHOWERS AND STORMS THROUGH THE WEEKEND THEN MAINLY DRY AND
COOLER MUCH OF NEXT WEEK.
SAT-SAT NGT...COVERAGE OF STORMS AND SEVERE POTENTIAL ARE THE MAIN
CHALLENGES. MODEL SOUNDINGS GENERALLY SHOW DECENT ELEVATED MIXED
LAYER OR CAP DEVELOPING OVER MUCH OF THE AREA SUPPRESSING CONVECTION
FOR MUCH OF THE DAY. THIS WILL ALSO SPELL VERY WARM AND HUMID
CONDITIONS WITH HIGHS MID 80S TO NEAR 90F AND DEWPTS UPPER 60S TO
LOWER 70S FOR PM HEAT INDICES FROM NEAR 90 NORTH TO AROUND 100 SOUTH.
SEVERAL FCST SOUNDINGS THOUGH SHOW THE CAP WEAKENING AFTER 20-21Z
WITH PASSAGE OF SFC-850 MB COOL FRONTS AND THEREFORE WOULD ANTICIPATE
INCREASING STORM COVERAGE BY LATE AFTN/EVE MAINLY SOUTH OF I-80
VICINITY OF FRONT AND ELEVATED CONVERGENCE AND MOISTURE ADVECTION ON
NOSE OF INCREASING SWLY LOW LEVEL JET. A FEW SEVERE STORMS POSSIBLE
GIVEN MODERATE TO STRONG INSTABILITY (SBCAPE 2500-3500 J/KG) AND
SHEAR (0-6KM 35-50 KTS). MAIN THREAT BEING DAMAGING WINDS WITH LARGE
HAIL RISK SECONDARY AND CONFINED TO SUPERCELLS OR DECENT MESOCYCLONES
GIVEN ABUNDANCE OF MOISTURE IN ATMOSPHERIC COLUMN CHARACTERIZED BY
PWATS OF 1.6-1.9 INCHES AND WARM CLOUD DEPTHS UP AROUND 13KFT AGL...
WHICH POSES RISK OF LOCALLY HEAVY RAIN OF 2+ INCHES WITH POTENTIAL
FOR BACKBUILDING AND ISOLATED HIGHER AMOUNTS WITH VEERED SWLY LOW LEVEL
JET.
SUN-SUN NGT...DIGGING PV ANOMALY FROM UPPER MIDWEST INTO GREAT LAKES
TO USHER IN SECONDARY AND STRONGER COOL FRONT SUNDAY PM. WILL SEE
CHANCES FOR ADDITIONAL SHOWERS AND STORMS MAINLY DURING THE PM INTO
EARLY EVE WITH THIS FRONT WITH BEST CHANCES OVER NORTHEAST 1/3-1/2 OF THE
CWA. NAM AND GFS SHOWING 40-50 KTS OF 0-6KM BULK SHEAR AND WITH
INVERTED V SOUNDINGS AND DRIER AIR ALOFT WILL NEED TO WATCH FOR POTENTIAL
OF MORE ORGANIZED AND STRONGER STORMS CONTAINING GUSTY WINDS AND HAIL.
SUNDAY LOOKS TO BE THE LAST WARM DAY FOR A WHILE... WHICH OF LATE MEANS
LAST DAY AROUND NORMAL.
MON-THU...MEDIUM RANGE MODELS AND ENSEMBLES IN GOOD AGREEMENT WITH THE
OVERALL PATTERN DEPICTING A DEEP UPPER TROUGH OVER THE EASTERN HALF OF THE
CONUS. THIS WILL RESULT IN ANOTHER PERIOD OF GENERALLY BELOW NORMAL
TEMPS...WHICH MAY FEATURE A MORNING OR TWO OF NEAR RECORD LOWS TUE-WED.
CHALLENGE ASIDE FROM TEMPS WILL BE WHETHER ANY PM SHOWER CHANCES EXIST
WITH THE COOLER AIR ALOFT AND ANY IMPULSES IN NORTHWEST FLOW... BUT TOO
FAR OUT AND PROBS APPEAR TOO LOW FOR MUCH MENTION OF PCPN UNTIL POSSIBLY
LATE WEEK AHEAD OF POTENTIALLY ANOTHER SHOT OF COOLER AIR BEYOND THE
SCOPE OF THE CURRENT EXTENDED.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON)
ISSUED AT 1239 PM CDT FRI JUL 25 2014
CONDITIONS WILL IMPROVE TO VFR THROUGH 00Z/26 AS THE NOCTURNAL
TSRA COMPLEX MOVES INTO SOUTHERN ILLINOIS. THE POTENTIAL DOES
EXIST FOR SOME ISOLATED SHRA/TSRA THROUGH SUNSET THAT MAY PRODUCE
BRIEF MVFR CONDITIONS IF THEY AFFECT A TAF SITE. AFT 06Z/26 VFR
CONDITIONS ARE GENERALLY EXPECTED BUT SPOTTY MVFR CONDITIONS MAY
DEVELOP THROUGH SUNRISE DUE TO WET GROUND.
&&
.DVN WATCHES/WARNINGS/ADVISORIES...
IA...NONE.
IL...NONE.
MO...NONE.
&&
$$
UPDATE...08
SYNOPSIS...HAASE
SHORT TERM...HAASE
LONG TERM...05
AVIATION...08
AREA FORECAST DISCUSSION
NWS QUAD CITIES IA IL
1047 AM CDT FRI JUL 25 2014
.UPDATE...
ISSUED AT 1041 AM CDT FRI JUL 25 2014
THE CURRENT THUNDERSTORM COMPLEX CONTINUES TO SLOWLY DECAY AS IT
MOVES EAST OF THE MISSISSIPPI. A MESO HIGH OVER NORTHEAST IOWA IS
STARTING TO COLLAPSE WHICH IS CAUSING A PERIOD OF STRONG WINDS ON
THE BACK SIDE OF THE PRECIPITATION.
NEW CONVECTION HAS DEVELOPED ACROSS NORTHERN IOWA WHICH APPEARS TO
BE ASSOCIATED WITH A WEAK THETA E GRADIENT. RECENT RADAR TRENDS
SHOW SOME WEAKENING OF THIS CONVECTION.
THE RAIN WILL END FROM WEST TO EAST THROUGH MID DAY AS WARMER
TEMPERATURES BUILDS IN ALOFT. THE POTENTIAL FOR CONVECTION WILL
HAVE TO BE RE-EVALUATED FOR THE AFTERNOON HOURS.
UPDATE ISSUED AT 700 AM CDT FRI JUL 25 2014
MCS OVER THE DVN CWA EARLY THIS MORNING WITH LOCALLY HEAVY RAINFALL
IN THE SOME OF THE STRONGER STORMS. IR SATELLITE SHOWED WARMING
TOPS IN OUR NORTHERN CWA WHICH ALSO IS INDICATED ON DOPPLER RADAR
WITH A WEAKENING TREND. THE ENTIRE MCS WILL GRADUALLY WEAKEN AS IT
PUSHES SOUTHEAST THIS MORNING AND THE HRRR MESO MODEL SHOWS THE BACK
EDGE OF THE MCS EXITING OUR SE CWA BY 1 PM. MANY AREAS SHOULD PICK
UP 1/4 TO 1/2 INCH OF RAIN WITH ISOLATED 1 INCH POSSIBLE.
&&
.SYNOPSIS...
ISSUED AT 345 AM CDT FRI JUL 25 2014
ELEVATED CONVECTION HAS FIRED IN THE PAST FEW HOURS ACROSS PORTIONS
OF NORTHERN/CENTRAL IA AND INTO WESTERN/SOUTHERN MN. THIS IS OCCURRING
ON THE NOSE OF A 50+ KNOT LOW LEVEL JET ON THE EASTERN EDGE OF A CAPPED
ELEVATED MIXED LAYER. SPC MESO ANALYSIS SHOWS THE BETTER MOISTURE
TRANSPORT IS STILL WEST OF THE DVN CWA WITH THE HIGHEST BULK SHEAR
VALUES IN SOUTHERN MN. PRECIPITABLE WATERS RANGE FROM 2.10 INCHES
IN WESTERN IA TO LESS THAN AN INCH IN NORTHERN IL. IR SATELLITE
LOOPS INDICATE TOPS CONTINUE TO RAPIDLY COOL AS THE THUNDERSTORM
ACTIVITY MOVES SOUTHEAST. A SHORT WAVE TROUGH WAS ALSO LIFTING
EASTWARD ACROSS THE NORTHERN/CENTRAL PLAINS AROUND A CLOSED UPPER
LOW IN SOUTHERN ALBERTA.
A COOL/STABLE SURFACE LAYER WAS NOTED ACROSS THE DVN CWA WITH 3 AM
TEMPERATURES IN THE MID 50S TO MID 60S...WHILE READINGS WERE WELL
INTO THE 70S TO LOWER 80S IN THE CENTRAL/SOUTHERN PLAINS.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 345 AM CDT FRI JUL 25 2014
FORECAST FOCUS ON THUNDERSTORMS MAINLY THIS MORNING AND TEMPERATURES.
TODAY...FORCING AND RAPIDLY INCREASING MOISTURE WILL ALLOW THUNDERSTORMS
TO CONTINUE TO DEVELOP/SPREAD ACROSS MUCH OF THE CWA THIS MORNING ON
THE NOSE OF THE STRONG LOW LEVEL JET...AS IT VEERS INTO THE AREA. DUE
TO THE ELEVATED NATURE OF THE STORMS AND THE COOL/STABLE SURFACE ENVIRONMENT
SEVERE WEATHER IS NOT EXPECTED. FREEZING LEVELS ARE QUITE HIGH AT NEARLY
15K FT. HOWEVER...SOME OF THE STRONGER STORMS MAY PRODUCE FREQUENT LIGHTNING...
SUB-SEVERE HAIL AND LOCALLY HEAVY RAINFALL. LATER THIS MORNING THE LOW
LEVEL JET WILL WEAKEN CONSIDERABLY ALONG WITH THE PASSAGE OF THE SHORT
WAVE TROUGH. A STRENGTHENING CAP WILL ALSO SPREAD EASTWARD INTO THE
CWA. THIS WILL DIMINISH OR END THE THUNDERSTORM ACTIVITY BY AFTERNOON
SO WILL HAVE LIKELY TO CATEGORICAL POPS THIS MORNING AND ONLY SMALL
POPS THIS AFTERNOON. EXPECTING EXTENSIVE CLOUD COVER TO LINGER INTO
THE AFTERNOON ESPECIALLY IN OUR EAST WHILE MORE SUNSHINE DEVELOPS IN
OUR WEST. MODELS REALLY SURGE THE WARM 850 MB TEMPERATURES INTO OUR
WESTERN CWA WITH +20C NOTED LATER IN THE AFTERNOON. I WILL FORECAST
MAXIMUM TEMPERATURES RANGING FROM THE MID 80S SW TO THE MID 70S NE.
HOWEVER...DEPENDING ON AMOUNT OF LINGERING CLOUDS (OR LACK OF) THIS
AFTERNOON THESE READINGS MAY NEED TO BE RE-VISITED.
TONIGHT...STRONG CAPPING ENVIRONMENT OVERSPREADS THE CWA EXCEPT
POSSIBLY OUR FAR EASTERN CWA. MODELS INSIST ON DEVELOPING CONVECTION
IN OUR EASTERN CWA AS THE LOW LEVEL JET STRENGTHENS AGAIN...BUT THERE
IS THE POTENTIAL THE STORMS MAY END UP FIRING EAST OF THE DVN CWA.
WILL HAVE CHANCE POPS TO COVER THIS SCENARIO BUT CONFIDENCE IS RATHER
LOW AT THIS POINT. THIS WILL BE A WARMER NIGHT WITH MINIMUM TEMPERATURES
IN THE MID 60S TO LOWER 70S.
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 345 AM CDT FRI JUL 25 2014
CHANCES FOR SHOWERS AND STORMS THROUGH THE WEEKEND THEN MAINLY DRY AND
COOLER MUCH OF NEXT WEEK.
SAT-SAT NGT...COVERAGE OF STORMS AND SEVERE POTENTIAL ARE THE MAIN
CHALLENGES. MODEL SOUNDINGS GENERALLY SHOW DECENT ELEVATED MIXED
LAYER OR CAP DEVELOPING OVER MUCH OF THE AREA SUPPRESSING CONVECTION
FOR MUCH OF THE DAY. THIS WILL ALSO SPELL VERY WARM AND HUMID
CONDITIONS WITH HIGHS MID 80S TO NEAR 90F AND DEWPTS UPPER 60S TO
LOWER 70S FOR PM HEAT INDICES FROM NEAR 90 NORTH TO AROUND 100 SOUTH.
SEVERAL FCST SOUNDINGS THOUGH SHOW THE CAP WEAKENING AFTER 20-21Z
WITH PASSAGE OF SFC-850 MB COOL FRONTS AND THEREFORE WOULD ANTICIPATE
INCREASING STORM COVERAGE BY LATE AFTN/EVE MAINLY SOUTH OF I-80
VICINITY OF FRONT AND ELEVATED CONVERGENCE AND MOISTURE ADVECTION ON
NOSE OF INCREASING SWLY LOW LEVEL JET. A FEW SEVERE STORMS POSSIBLE
GIVEN MODERATE TO STRONG INSTABILITY (SBCAPE 2500-3500 J/KG) AND
SHEAR (0-6KM 35-50 KTS). MAIN THREAT BEING DAMAGING WINDS WITH LARGE
HAIL RISK SECONDARY AND CONFINED TO SUPERCELLS OR DECENT MESOCYCLONES
GIVEN ABUNDANCE OF MOISTURE IN ATMOSPHERIC COLUMN CHARACTERIZED BY
PWATS OF 1.6-1.9 INCHES AND WARM CLOUD DEPTHS UP AROUND 13KFT AGL...
WHICH POSES RISK OF LOCALLY HEAVY RAIN OF 2+ INCHES WITH POTENTIAL
FOR BACKBUILDING AND ISOLATED HIGHER AMOUNTS WITH VEERED SWLY LOW LEVEL
JET.
SUN-SUN NGT...DIGGING PV ANOMALY FROM UPPER MIDWEST INTO GREAT LAKES
TO USHER IN SECONDARY AND STRONGER COOL FRONT SUNDAY PM. WILL SEE
CHANCES FOR ADDITIONAL SHOWERS AND STORMS MAINLY DURING THE PM INTO
EARLY EVE WITH THIS FRONT WITH BEST CHANCES OVER NORTHEAST 1/3-1/2 OF THE
CWA. NAM AND GFS SHOWING 40-50 KTS OF 0-6KM BULK SHEAR AND WITH
INVERTED V SOUNDINGS AND DRIER AIR ALOFT WILL NEED TO WATCH FOR POTENTIAL
OF MORE ORGANIZED AND STRONGER STORMS CONTAINING GUSTY WINDS AND HAIL.
SUNDAY LOOKS TO BE THE LAST WARM DAY FOR A WHILE... WHICH OF LATE MEANS
LAST DAY AROUND NORMAL.
MON-THU...MEDIUM RANGE MODELS AND ENSEMBLES IN GOOD AGREEMENT WITH THE
OVERALL PATTERN DEPICTING A DEEP UPPER TROUGH OVER THE EASTERN HALF OF THE
CONUS. THIS WILL RESULT IN ANOTHER PERIOD OF GENERALLY BELOW NORMAL
TEMPS...WHICH MAY FEATURE A MORNING OR TWO OF NEAR RECORD LOWS TUE-WED.
CHALLENGE ASIDE FROM TEMPS WILL BE WHETHER ANY PM SHOWER CHANCES EXIST
WITH THE COOLER AIR ALOFT AND ANY IMPULSES IN NORTHWEST FLOW... BUT TOO
FAR OUT AND PROBS APPEAR TOO LOW FOR MUCH MENTION OF PCPN UNTIL POSSIBLY
LATE WEEK AHEAD OF POTENTIALLY ANOTHER SHOT OF COOLER AIR BEYOND THE
SCOPE OF THE CURRENT EXTENDED.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SATURDAY MORNING)
ISSUED AT 700 AM CDT FRI JUL 25 2014
SHOWERS AND THUNDERSTORMS WILL BE OVER THE TAF SITES THIS MORNING
WITH BRIEF MVFR CIGS/VIS OTHERWISE MAINLY VFR CONDS THROUGH TONIGHT.
SOUTH WINDS 10 TO 20 KNOTS TODAY THEN AROUND 10 KNOTS TONIGHT.
&&
.DVN WATCHES/WARNINGS/ADVISORIES...
IA...NONE.
IL...NONE.
MO...NONE.
&&
$$
UPDATE...08
SYNOPSIS...HAASE
SHORT TERM...HAASE
LONG TERM...05
AVIATION...HAASE
AREA FORECAST DISCUSSION
NWS QUAD CITIES IA IL
702 AM CDT FRI JUL 25 2014
.UPDATE...
ISSUED AT 700 AM CDT FRI JUL 25 2014
MCS OVER THE DVN CWA EARLY THIS MORNING WITH LOCALLY HEAVY RAINFALL
IN THE SOME OF THE STRONGER STORMS. IR SATELLITE SHOWED WARMING
TOPS IN OUR NORTHERN CWA WHICH ALSO IS INDICATED ON DOPPLER RADAR
WITH A WEAKENING TREND. THE ENTIRE MCS WILL GRADUALLY WEAKEN AS IT
PUSHES SOUTHEAST THIS MORNING AND THE HRRR MESO MODEL SHOWS THE BACK
EDGE OF THE MCS EXITING OUR SE CWA BY 1 PM. MANY AREAS SHOULD PICK
UP 1/4 TO 1/2 INCH OF RAIN WITH ISOLATED 1 INCH POSSIBLE.
&&
.SYNOPSIS...
ISSUED AT 345 AM CDT FRI JUL 25 2014
ELEVATED CONVECTION HAS FIRED IN THE PAST FEW HOURS ACROSS PORTIONS
OF NORTHERN/CENTRAL IA AND INTO WESTERN/SOUTHERN MN. THIS IS OCCURRING
ON THE NOSE OF A 50+ KNOT LOW LEVEL JET ON THE EASTERN EDGE OF A CAPPED
ELEVATED MIXED LAYER. SPC MESO ANALYSIS SHOWS THE BETTER MOISTURE
TRANSPORT IS STILL WEST OF THE DVN CWA WITH THE HIGHEST BULK SHEAR
VALUES IN SOUTHERN MN. PRECIPITABLE WATERS RANGE FROM 2.10 INCHES
IN WESTERN IA TO LESS THAN AN INCH IN NORTHERN IL. IR SATELLITE
LOOPS INDICATE TOPS CONTINUE TO RAPIDLY COOL AS THE THUNDERSTORM
ACTIVITY MOVES SOUTHEAST. A SHORT WAVE TROUGH WAS ALSO LIFTING
EASTWARD ACROSS THE NORTHERN/CENTRAL PLAINS AROUND A CLOSED UPPER
LOW IN SOUTHERN ALBERTA.
A COOL/STABLE SURFACE LAYER WAS NOTED ACROSS THE DVN CWA WITH 3 AM
TEMPERATURES IN THE MID 50S TO MID 60S...WHILE READINGS WERE WELL
INTO THE 70S TO LOWER 80S IN THE CENTRAL/SOUTHERN PLAINS.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 345 AM CDT FRI JUL 25 2014
FORECAST FOCUS ON THUNDERSTORMS MAINLY THIS MORNING AND TEMPERATURES.
TODAY...FORCING AND RAPIDLY INCREASING MOISTURE WILL ALLOW THUNDERSTORMS
TO CONTINUE TO DEVELOP/SPREAD ACROSS MUCH OF THE CWA THIS MORNING ON
THE NOSE OF THE STRONG LOW LEVEL JET...AS IT VEERS INTO THE AREA. DUE
TO THE ELEVATED NATURE OF THE STORMS AND THE COOL/STABLE SURFACE ENVIRONMENT
SEVERE WEATHER IS NOT EXPECTED. FREEZING LEVELS ARE QUITE HIGH AT NEARLY
15K FT. HOWEVER...SOME OF THE STRONGER STORMS MAY PRODUCE FREQUENT LIGHTNING...
SUB-SEVERE HAIL AND LOCALLY HEAVY RAINFALL. LATER THIS MORNING THE LOW
LEVEL JET WILL WEAKEN CONSIDERABLY ALONG WITH THE PASSAGE OF THE SHORT
WAVE TROUGH. A STRENGTHENING CAP WILL ALSO SPREAD EASTWARD INTO THE
CWA. THIS WILL DIMINISH OR END THE THUNDERSTORM ACTIVITY BY AFTERNOON
SO WILL HAVE LIKELY TO CATEGORICAL POPS THIS MORNING AND ONLY SMALL
POPS THIS AFTERNOON. EXPECTING EXTENSIVE CLOUD COVER TO LINGER INTO
THE AFTERNOON ESPECIALLY IN OUR EAST WHILE MORE SUNSHINE DEVELOPS IN
OUR WEST. MODELS REALLY SURGE THE WARM 850 MB TEMPERATURES INTO OUR
WESTERN CWA WITH +20C NOTED LATER IN THE AFTERNOON. I WILL FORECAST
MAXIMUM TEMPERATURES RANGING FROM THE MID 80S SW TO THE MID 70S NE.
HOWEVER...DEPENDING ON AMOUNT OF LINGERING CLOUDS (OR LACK OF) THIS
AFTERNOON THESE READINGS MAY NEED TO BE RE-VISITED.
TONIGHT...STRONG CAPPING ENVIRONMENT OVERSPREADS THE CWA EXCEPT
POSSIBLY OUR FAR EASTERN CWA. MODELS INSIST ON DEVELOPING CONVECTION
IN OUR EASTERN CWA AS THE LOW LEVEL JET STRENGTHENS AGAIN...BUT THERE
IS THE POTENTIAL THE STORMS MAY END UP FIRING EAST OF THE DVN CWA.
WILL HAVE CHANCE POPS TO COVER THIS SCENARIO BUT CONFIDENCE IS RATHER
LOW AT THIS POINT. THIS WILL BE A WARMER NIGHT WITH MINIMUM TEMPERATURES
IN THE MID 60S TO LOWER 70S.
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 345 AM CDT FRI JUL 25 2014
CHANCES FOR SHOWERS AND STORMS THROUGH THE WEEKEND THEN MAINLY DRY AND
COOLER MUCH OF NEXT WEEK.
SAT-SAT NGT...COVERAGE OF STORMS AND SEVERE POTENTIAL ARE THE MAIN
CHALLENGES. MODEL SOUNDINGS GENERALLY SHOW DECENT ELEVATED MIXED
LAYER OR CAP DEVELOPING OVER MUCH OF THE AREA SUPPRESSING CONVECTION
FOR MUCH OF THE DAY. THIS WILL ALSO SPELL VERY WARM AND HUMID
CONDITIONS WITH HIGHS MID 80S TO NEAR 90F AND DEWPTS UPPER 60S TO
LOWER 70S FOR PM HEAT INDICES FROM NEAR 90 NORTH TO AROUND 100 SOUTH.
SEVERAL FCST SOUNDINGS THOUGH SHOW THE CAP WEAKENING AFTER 20-21Z
WITH PASSAGE OF SFC-850 MB COOL FRONTS AND THEREFORE WOULD ANTICIPATE
INCREASING STORM COVERAGE BY LATE AFTN/EVE MAINLY SOUTH OF I-80
VICINITY OF FRONT AND ELEVATED CONVERGENCE AND MOISTURE ADVECTION ON
NOSE OF INCREASING SWLY LOW LEVEL JET. A FEW SEVERE STORMS POSSIBLE
GIVEN MODERATE TO STRONG INSTABILITY (SBCAPE 2500-3500 J/KG) AND
SHEAR (0-6KM 35-50 KTS). MAIN THREAT BEING DAMAGING WINDS WITH LARGE
HAIL RISK SECONDARY AND CONFINED TO SUPERCELLS OR DECENT MESOCYCLONES
GIVEN ABUNDANCE OF MOISTURE IN ATMOSPHERIC COLUMN CHARACTERIZED BY
PWATS OF 1.6-1.9 INCHES AND WARM CLOUD DEPTHS UP AROUND 13KFT AGL...
WHICH POSES RISK OF LOCALLY HEAVY RAIN OF 2+ INCHES WITH POTENTIAL
FOR BACKBUILDING AND ISOLATED HIGHER AMOUNTS WITH VEERED SWLY LOW LEVEL
JET.
SUN-SUN NGT...DIGGING PV ANOMALY FROM UPPER MIDWEST INTO GREAT LAKES
TO USHER IN SECONDARY AND STRONGER COOL FRONT SUNDAY PM. WILL SEE
CHANCES FOR ADDITIONAL SHOWERS AND STORMS MAINLY DURING THE PM INTO
EARLY EVE WITH THIS FRONT WITH BEST CHANCES OVER NORTHEAST 1/3-1/2 OF THE
CWA. NAM AND GFS SHOWING 40-50 KTS OF 0-6KM BULK SHEAR AND WITH
INVERTED V SOUNDINGS AND DRIER AIR ALOFT WILL NEED TO WATCH FOR POTENTIAL
OF MORE ORGANIZED AND STRONGER STORMS CONTAINING GUSTY WINDS AND HAIL.
SUNDAY LOOKS TO BE THE LAST WARM DAY FOR A WHILE... WHICH OF LATE MEANS
LAST DAY AROUND NORMAL.
MON-THU...MEDIUM RANGE MODELS AND ENSEMBLES IN GOOD AGREEMENT WITH THE
OVERALL PATTERN DEPICTING A DEEP UPPER TROUGH OVER THE EASTERN HALF OF THE
CONUS. THIS WILL RESULT IN ANOTHER PERIOD OF GENERALLY BELOW NORMAL
TEMPS...WHICH MAY FEATURE A MORNING OR TWO OF NEAR RECORD LOWS TUE-WED.
CHALLENGE ASIDE FROM TEMPS WILL BE WHETHER ANY PM SHOWER CHANCES EXIST
WITH THE COOLER AIR ALOFT AND ANY IMPULSES IN NORTHWEST FLOW... BUT TOO
FAR OUT AND PROBS APPEAR TOO LOW FOR MUCH MENTION OF PCPN UNTIL POSSIBLY
LATE WEEK AHEAD OF POTENTIALLY ANOTHER SHOT OF COOLER AIR BEYOND THE
SCOPE OF THE CURRENT EXTENDED.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SATURDAY MORNING)
ISSUED AT 700 AM CDT FRI JUL 25 2014
SHOWERS AND THUNDERSTORMS WILL BE OVER THE TAF SITES THIS MORNING
WITH BRIEF MVFR CIGS/VIS OTHERWISE MAINLY VFR CONDS THROUGH TONIGHT.
SOUTH WINDS 10 TO 20 KNOTS TODAY THEN AROUND 10 KNOTS TONIGHT.
&&
.DVN WATCHES/WARNINGS/ADVISORIES...
IA...NONE.
IL...NONE.
MO...NONE.
&&
$$
UPDATE...HAASE
SYNOPSIS...HAASE
SHORT TERM...HAASE
LONG TERM...05
AVIATION...HAASE
AREA FORECAST DISCUSSION
NWS GOODLAND KS
913 PM MDT SAT JUL 26 2014
.UPDATE...
ISSUED AT 905 PM MDT SAT JUL 26 2014
DUE TO ENVIRONMENT BEING MORE STABLE THAN ANTICIPATED...HAVE
LOWERED RAINFALL CHANCES OVER EAST CENTRAL COLORADO FOR THE
EVENING. HAVE NOTICED SOME STORMS ARE FINALLY ABLE TO MOVE INTO
EAST CENTRAL COLORADO AS ELEVATED CAPE HAS BEGUN TO DEVELOP AND
THE 500MB SHORT WAVE TROUGH MOVES IN. MODELS KEEP THE UPPER LEVEL
TROUGH OVER THE SOUTH/SOUTHWEST PART OF THE AREA TONIGHT WHICH IS
WHERE THE ELEVATED CAPE WILL BE. STORM MOTION WILL BE AROUND 10
MPH SO IF STORMS DEVELOP THEY WILL BE MOVING VERY SLOW TO THE
SOUTHEAST WHICH MAY LEAD TO HEAVY RAINFALL. MOVED CHANCES FOR RAIN
FURTHER SOUTH...MAINLY ALONG/SOUTH OF HWY 40 WHERE LIFT AND
INSTABILITY ARE BEST. AM STILL THINKING THE MAJORITY OF THE STORM
COVERAGE WILL BE SOUTH OF GREELEY/WICHITA COUNTIES WHERE ELEVATED
INSTABILITY IS STRONGEST.
UPDATE ISSUED AT 647 PM MDT SAT JUL 26 2014
ALLOWED HEAT ADVISORY TO EXPIRE FOR NORTON/GRAHAM COUNTIES.
AS FAR AS PRECIP. FORECAST GOES...AM HAVING MORE CONFIDENCE THE
BETTER STORM COVERAGE WILL BE JUST SOUTH OF THE AREA WHERE STORMS
ARE CURRENTLY FIRING. OVERNIGHT ELEVATED CAPE DEVELOPS OVER THE
NORTHERN HALF OF THE AREA AS THE COLD FRONT MOVES IN. LIMITING
FACTOR WILL BE THE STRENGTH OF THE WEAK SHORT WAVE TROUGH MOVING
OVER THE NORTHERN HALF OF THE AREA AT THAT TIME. WILL CONTINUE TO
ANALYZE LATEST MODEL DATA BEFORE ALTERING FORECAST.
&&
.SHORT TERM...(THIS AFTERNOON THROUGH SUNDAY)
ISSUED AT 131 PM MDT SAT JUL 26 2014
LATEST WV IMAGE AND RAP UPPER LEVEL ANALYSIS SHOW BROAD RIDGE STILL
IN PLACE FROM THE DESERT SOUTHWEST ACROSS THE SOUTHERN PLAINS AND
INTO THE SOUTHERN MISSISSIPPI VALLEY. A PLUME OF MONSOONAL MOISTURE
CONTINUES TO ROUND THE WESTERN AND NORTHERN PERIPHERY OF THIS RIDGE
INTO THE CENTRAL ROCKIES AND HIGH PLAINS. A CLOSED LOW IS CENTERED
OVER SOUTHERN MANITOBA CANADA WITH A SHORTWAVE TROUGH OUT AHEAD OF
THIS ENTERING THE NORTHERN MISSISSIPPI VALLEY. AT THE SURFACE LOW
PRESSURE IS IN PLACE OVER OUR CWA WITH SEVERAL WEAK CONVERGENT AREAS
ACROSS OUR SOUTH...AND A COLD FRONT ENTERING NORTHWEST KANSAS FROM
COLORADO AND SOUTHWEST NEBRASKA.
RAP ANALYSIS INDICATES MODERATE SB/MIXED LAYER CAPE VALUES AHEAD OF
MEAN SURFACE TROUGH AXIS ACROSS MOST OF OUR CWA. SHEER IS NOT
PARTICULARLY IMPRESSIVE...HOWEVER WITH SOUNDINGS SHOWING INVERTED V
TYPE SOUNDINGS AND DCAPE 1000 J/KG OR HIGHER MICROBURST POTENTIAL IS
THERE FOR ANY THUNDERSTORM ACTIVITY. GUIDANCE CONTINUES TO FAVOR THE
SOUTHERN PART OF OUR CWA FOR THUNDERSTORM COVERAGE...MAINLY ALONG
AND AHEAD OF COLD FRONT. WEAK FORCING ROTATING FROM THE NORTH
LATER THIS EVENING MAY ALSO SUPPORT ADDITIONAL POST FRONTAL
THUNDERSTORM DEVELOPMENT. POP ADJUSTMENTS WERE MADE TO REFLECT
THESE TRENDS THROUGH TONIGHT. SUBSIDENT AIR MASS APPEARS TO BE IN
PLACE OVER MOST OF THE CWA SUNDAY...THOUGH BY SUNDAY AFTERNOON
UPSLOPE COMBINED WITH OVERRUNNING ALONG STALLED FRONTAL ZONE IN
COLORADO MAY ALLOW FOR SHOWER/THUNDERSTORM DEVELOPMENT INTO THE SW
PART OF THE CWA IN THE AFTERNOON.
TEMPERATURES SATURDAY SHOULD BE COOLER...HOWEVER THERE IS QUITE A
BIT OF SPREAD DUE TO NAM/SREF LINGERING PRECIP MOST OF THE DAY
ACROSS MUCH OF THE CWA. I AM NOT FAVORING THIS SOLUTION AS BETTER
SUPPORT FOR SHOWER/THUNDERSTORM (AND ANY LOW CLOUD COVER) WOULD BE
FURTHER WEST AND SOUTHWEST. IF THE NAM/SREF WERE CORRECT THEN HIGHS
IN THE LOW 80S FOR WESTERN PARTS OF THE CWA. BASED ON THE FAVORED
WARMER SOLUTION WE SHOULD SEE HIGHS WARM TO NEAR NORMAL VALUES IN
THE UPPER 80S FOR A LOT OF THE CWA SUNDAY.
.LONG TERM...(SUNDAY NIGHT THROUGH SATURDAY)
ISSUED AT 232 PM MDT SAT JUL 26 2014
SUNDAY NIGHT THROUGH TUESDAY...FORECAST CONCERNS FOR THE PERIOD
INCLUDE COOLING TEMPERATURES AND PRECIPITATION CHANCES...MAINLY IN
THE SOUTHWESTERN PORTION OF THE CWA. NEAR TERM MODELS IN GENERAL
AGREEMENT WITH LARGE SCALE PATTERN AND ALL SUGGEST A MUCH COOLER
START TO THE WEEK THAN THE PAST WEEK.
CWA WILL FIND ITSELF ON THE NORTHEAST FRINGE OF PERSISTENT H5 RIDGE
OVER THE ROCKIES. DESPITE THE RIDGE POSITION...PERIODS OF ASCENT
ACROSS WILL PERIODICALLY DEVELOP AS NUMEROUS SMALL SCALE
DISTURBANCES AND PERSISTENT WEAK WAA REMAIN ACROSS WESTERN HALF OF
THE CWA. ALTHOUGH FORCING IS WEAK...DO NOT SEE ANY REASON WHY MID
LEVELS WILL DRY OUT DURING THE PERIOD AND WITH ELEVATED CAPE PRESENT
THROUGHOUT THINK WE WILL SEE SEVERAL PERIODS OF SHOWERS AND WEAK
THUNDERSTORMS. TRIED TO ADD SOME DIURNAL COMPONENT TO WX TIMING AS
THINK BEST CHANCES WILL BE GENERALLY IN THE OVERNIGHT HOURS AS
MODEST LOW LEVEL JET DEVELOPS TO AID IN MOISTURE ADVECTION/FORCED
ASCENT. GIVEN THE POSITION OF GREATER INSTABILITY AND OVERALL
PATTERN AM NOT EXPECTING LARGE PRECIPITATION AMOUNTS FOR THE PERIOD.
COLD FRONTAL PASSAGE COMBINED WITH PERSISTENT CLOUD COVER WILL
LIKELY LEAD TO MUCH COOLER TEMPERATURES FOR THE PERIOD...ABOUT 10 TO
20 DEGREES COOLER THAN PAST FEW DAYS.
IN THE EXTENDED(TUESDAY NIGHT-SATURDAY)...SIMILAR PATTERN TO
CONTINUE ACROSS TRI STATE AREA THROUGH THE END OF THE WEEK AS H5
RIDGE GRADUALLY AMPLIFIES IN RESPONSE TO TROUGHING DEVELOPING ACROSS
THE SOUTHEAST AND MIDWEST. GEFS AND OPERATIONAL MODELS CONTINUE TO
SUPPORT A HIGH PRECIP POTENTIAL ON TUESDAY NIGHT AND WEDNESDAY AS
MORE SIGNIFICANT SHORT WAVE TROUGH MOVES ACROSS THE AREA. MOISTURE
AND INSTABILITY SHOULD ALREADY BE IN PLACE WITH MAIN CONCERN BEING
HOW FAR NORTH/EAST PRECIP SHIELD WILL GO. STILL THINK BEST CHANCE
FOR RAIN WILL BE ACROSS SOUTHWESTERN CWA SO MADE ONLY MINOR CHANGES
HERE. OTHERWISE...COOLER TEMPERATURES AS A FEW CHANCES FOR LIGHT
PRECIPITATION ARE ANTICIPATED FOR THE PERIOD.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z SUNDAY EVENING)
ISSUED AT 540 PM MDT SAT JUL 26 2014
VFR CONDITIONS FORECAST FOR THE 0Z TAFS. THIS EVENING STORMS MAY
MOVE NEAR THE KGLD SITE. AM NOT TOO OPTIMISTIC SINCE STORMS SHOULD
REMAIN SOUTH OF THE SITE BUT DID KEEP THE MENTION IN SINCE IT WAS
IN THE PREVIOUS TAF. IN ADDITION ANY OUTFLOW BOUNDARIES MAY
GENERATE FURTHER CONVECTION WHICH IS VERY DIFFICULT TO PREDICT
BEFORE HAND SO A MENTION OF VCTS SEEMS FINE. OTHERWISE AS THE COLD
FRONT MOVES THROUGH OVERNIGHT CEILINGS WILL FALL TO NEAR MVFR FOR
A FEW HOURS AT KGLD.
FOR KMCK LIGHT NORTHERLY WINDS WILL PERSIST THROUGH THE PERIOD.
ANY STORMS THAT DEVELOP TONIGHT WILL REMAIN SOUTH OF THE SITE.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
UPDATE...JTL
SHORT TERM...DR
LONG TERM...JRM
AVIATION...JTL
AREA FORECAST DISCUSSION
NWS GOODLAND KS
658 PM MDT SAT JUL 26 2014
.UPDATE...
ISSUED AT 647 PM MDT SAT JUL 26 2014
ALLOWED HEAT ADVISORY TO EXPIRE FOR NORTON/GRAHAM COUNTIES.
AS FAR AS PRECIP. FORECAST GOES...AM HAVING MORE CONFIDENCE THE
BETTER STORM COVERAGE WILL BE JUST SOUTH OF THE AREA WHERE STORMS
ARE CURRENTLY FIRING. OVERNIGHT ELEVATED CAPE DEVELOPS OVER THE
NORTHERN HALF OF THE AREA AS THE COLD FRONT MOVES IN. LIMITING
FACTOR WILL BE THE STRENGTH OF THE WEAK SHORT WAVE TROUGH MOVING
OVER THE NORTHERN HALF OF THE AREA AT THAT TIME. WILL CONTINUE TO
ANALYZE LATEST MODEL DATA BEFORE ALTERING FORECAST.
UPDATE ISSUED AT 454 PM MDT SAT JUL 26 2014
INCREASED RAINFALL CHANCES OVER MAINLY EAST CENTRAL COLORADO AHEAD
OF THE STORMS MOVING OFF THE HIGHER TERRAIN FURTHER WEST. GENERAL
TREND WITH MODEL DATA HAS BEEN TO SLOW DOWN THE PROGRESSION OF THE
500MB SHORT WAVE TROUGH FOLLOWING THE STORMS. SOUNDINGS DO SHOW
ELEVATED CAPE...WITH THE MOST CAPE/LEAST CINH WHEN LIFTED FROM
700MB OR SO THIS EVENING. HOWEVER TREND IN DATA IS TO PLACE THE
BEST INSTABILITY JUST SOUTH OF THE AREA THEN BRING IT BACK NORTH
OVERNIGHT.
CURRENTLY AM THINKING THE BEST CHANCE FOR STORMS WILL BE OVER THE
SOUTHWEST QUADRANT OF THE AREA WHERE MODELS ALL AGREE THE 500MB
SHORT WAVE TROUGH WILL MOVE TONIGHT. FURTHER EAST AND NORTH THERE
IS LESS CONFIDENCE WHERE ELEVATED INSTABILITY IS HIGHER DUE TO A LACK OF
UPPER LEVEL FORCING TO GENERATE CONVECTION. HOWEVER BASED ON STORM
BEHAVIOR LAST NIGHT...ANY OUTFLOW BOUNDARIES MAY GENERATE FURTHER
CONVECTION DUE TO SOME ELEVATED CAPE PRESENT. DUE TO UNCERTAINTY
IN HOW CONVECTION WILL EVOLVE PAST MID EVENING...WILL LEAVE THE
CURRENT FORECAST AFTER THIS POINT AS IS AND UPDATE AS NEEDED.
&&
.SHORT TERM...(THIS AFTERNOON THROUGH SUNDAY)
ISSUED AT 131 PM MDT SAT JUL 26 2014
LATEST WV IMAGE AND RAP UPPER LEVEL ANALYSIS SHOW BROAD RIDGE STILL
IN PLACE FROM THE DESERT SOUTHWEST ACROSS THE SOUTHERN PLAINS AND
INTO THE SOUTHERN MISSISSIPPI VALLEY. A PLUME OF MONSOONAL MOISTURE
CONTINUES TO ROUND THE WESTERN AND NORTHERN PERIPHERY OF THIS RIDGE
INTO THE CENTRAL ROCKIES AND HIGH PLAINS. A CLOSED LOW IS CENTERED
OVER SOUTHERN MANITOBA CANADA WITH A SHORTWAVE TROUGH OUT AHEAD OF
THIS ENTERING THE NORTHERN MISSISSIPPI VALLEY. AT THE SURFACE LOW
PRESSURE IS IN PLACE OVER OUR CWA WITH SEVERAL WEAK CONVERGENT AREAS
ACROSS OUR SOUTH...AND A COLD FRONT ENTERING NORTHWEST KANSAS FROM
COLORADO AND SOUTHWEST NEBRASKA.
RAP ANALYSIS INDICATES MODERATE SB/MIXED LAYER CAPE VALUES AHEAD OF
MEAN SURFACE TROUGH AXIS ACROSS MOST OF OUR CWA. SHEER IS NOT
PARTICULARLY IMPRESSIVE...HOWEVER WITH SOUNDINGS SHOWING INVERTED V
TYPE SOUNDINGS AND DCAPE 1000 J/KG OR HIGHER MICROBURST POTENTIAL IS
THERE FOR ANY THUNDERSTORM ACTIVITY. GUIDANCE CONTINUES TO FAVOR THE
SOUTHERN PART OF OUR CWA FOR THUNDERSTORM COVERAGE...MAINLY ALONG
AND AHEAD OF COLD FRONT. WEAK FORCING ROTATING FROM THE NORTH
LATER THIS EVENING MAY ALSO SUPPORT ADDITIONAL POST FRONTAL
THUNDERSTORM DEVELOPMENT. POP ADJUSTMENTS WERE MADE TO REFLECT
THESE TRENDS THROUGH TONIGHT. SUBSIDENT AIR MASS APPEARS TO BE IN
PLACE OVER MOST OF THE CWA SUNDAY...THOUGH BY SUNDAY AFTERNOON
UPSLOPE COMBINED WITH OVERRUNNING ALONG STALLED FRONTAL ZONE IN
COLORADO MAY ALLOW FOR SHOWER/THUNDERSTORM DEVELOPMENT INTO THE SW
PART OF THE CWA IN THE AFTERNOON.
TEMPERATURES SATURDAY SHOULD BE COOLER...HOWEVER THERE IS QUITE A
BIT OF SPREAD DUE TO NAM/SREF LINGERING PRECIP MOST OF THE DAY
ACROSS MUCH OF THE CWA. I AM NOT FAVORING THIS SOLUTION AS BETTER
SUPPORT FOR SHOWER/THUNDERSTORM (AND ANY LOW CLOUD COVER) WOULD BE
FURTHER WEST AND SOUTHWEST. IF THE NAM/SREF WERE CORRECT THEN HIGHS
IN THE LOW 80S FOR WESTERN PARTS OF THE CWA. BASED ON THE FAVORED
WARMER SOLUTION WE SHOULD SEE HIGHS WARM TO NEAR NORMAL VALUES IN
THE UPPER 80S FOR A LOT OF THE CWA SUNDAY.
.LONG TERM...(SUNDAY NIGHT THROUGH SATURDAY)
ISSUED AT 232 PM MDT SAT JUL 26 2014
SUNDAY NIGHT THROUGH TUESDAY...FORECAST CONCERNS FOR THE PERIOD
INCLUDE COOLING TEMPERATURES AND PRECIPITATION CHANCES...MAINLY IN
THE SOUTHWESTERN PORTION OF THE CWA. NEAR TERM MODELS IN GENERAL
AGREEMENT WITH LARGE SCALE PATTERN AND ALL SUGGEST A MUCH COOLER
START TO THE WEEK THAN THE PAST WEEK.
CWA WILL FIND ITSELF ON THE NORTHEAST FRINGE OF PERSISTENT H5 RIDGE
OVER THE ROCKIES. DESPITE THE RIDGE POSITION...PERIODS OF ASCENT
ACROSS WILL PERIODICALLY DEVELOP AS NUMEROUS SMALL SCALE
DISTURBANCES AND PERSISTENT WEAK WAA REMAIN ACROSS WESTERN HALF OF
THE CWA. ALTHOUGH FORCING IS WEAK...DO NOT SEE ANY REASON WHY MID
LEVELS WILL DRY OUT DURING THE PERIOD AND WITH ELEVATED CAPE PRESENT
THROUGHOUT THINK WE WILL SEE SEVERAL PERIODS OF SHOWERS AND WEAK
THUNDERSTORMS. TRIED TO ADD SOME DIURNAL COMPONENT TO WX TIMING AS
THINK BEST CHANCES WILL BE GENERALLY IN THE OVERNIGHT HOURS AS
MODEST LOW LEVEL JET DEVELOPS TO AID IN MOISTURE ADVECTION/FORCED
ASCENT. GIVEN THE POSITION OF GREATER INSTABILITY AND OVERALL
PATTERN AM NOT EXPECTING LARGE PRECIPITATION AMOUNTS FOR THE PERIOD.
COLD FRONTAL PASSAGE COMBINED WITH PERSISTENT CLOUD COVER WILL
LIKELY LEAD TO MUCH COOLER TEMPERATURES FOR THE PERIOD...ABOUT 10 TO
20 DEGREES COOLER THAN PAST FEW DAYS.
IN THE EXTENDED(TUESDAY NIGHT-SATURDAY)...SIMILAR PATTERN TO
CONTINUE ACROSS TRI STATE AREA THROUGH THE END OF THE WEEK AS H5
RIDGE GRADUALLY AMPLIFIES IN RESPONSE TO TROUGHING DEVELOPING ACROSS
THE SOUTHEAST AND MIDWEST. GEFS AND OPERATIONAL MODELS CONTINUE TO
SUPPORT A HIGH PRECIP POTENTIAL ON TUESDAY NIGHT AND WEDNESDAY AS
MORE SIGNIFICANT SHORT WAVE TROUGH MOVES ACROSS THE AREA. MOISTURE
AND INSTABILITY SHOULD ALREADY BE IN PLACE WITH MAIN CONCERN BEING
HOW FAR NORTH/EAST PRECIP SHIELD WILL GO. STILL THINK BEST CHANCE
FOR RAIN WILL BE ACROSS SOUTHWESTERN CWA SO MADE ONLY MINOR CHANGES
HERE. OTHERWISE...COOLER TEMPERATURES AS A FEW CHANCES FOR LIGHT
PRECIPITATION ARE ANTICIPATED FOR THE PERIOD.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z SUNDAY EVENING)
ISSUED AT 540 PM MDT SAT JUL 26 2014
VFR CONDITIONS FORECAST FOR THE 0Z TAFS. THIS EVENING STORMS MAY
MOVE NEAR THE KGLD SITE. AM NOT TOO OPTIMISTIC SINCE STORMS SHOULD
REMAIN SOUTH OF THE SITE BUT DID KEEP THE MENTION IN SINCE IT WAS
IN THE PREVIOUS TAF. IN ADDITION ANY OUTFLOW BOUNDARIES MAY
GENERATE FURTHER CONVECTION WHICH IS VERY DIFFICULT TO PREDICT
BEFORE HAND SO A MENTION OF VCTS SEEMS FINE. OTHERWISE AS THE COLD
FRONT MOVES THROUGH OVERNIGHT CEILINGS WILL FALL TO NEAR MVFR FOR
A FEW HOURS AT KGLD.
FOR KMCK LIGHT NORTHERLY WINDS WILL PERSIST THROUGH THE PERIOD.
ANY STORMS THAT DEVELOP TONIGHT WILL REMAIN SOUTH OF THE SITE.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
UPDATE...JTL
SHORT TERM...DR
LONG TERM...JRM
AVIATION...JTL
AREA FORECAST DISCUSSION
NWS GOODLAND KS
546 PM MDT SAT JUL 26 2014
.UPDATE...
ISSUED AT 454 PM MDT SAT JUL 26 2014
INCREASED RAINFALL CHANCES OVER MAINLY EAST CENTRAL COLORADO AHEAD
OF THE STORMS MOVING OFF THE HIGHER TERRAIN FURTHER WEST. GENERAL
TREND WITH MODEL DATA HAS BEEN TO SLOW DOWN THE PROGRESSION OF THE
500MB SHORT WAVE TROUGH FOLLOWING THE STORMS. SOUNDINGS DO SHOW
ELEVATED CAPE...WITH THE MOST CAPE/LEAST CINH WHEN LIFTED FROM
700MB OR SO THIS EVENING. HOWEVER TREND IN DATA IS TO PLACE THE
BEST INSTABILITY JUST SOUTH OF THE AREA THEN BRING IT BACK NORTH
OVERNIGHT.
CURRENTLY AM THINKING THE BEST CHANCE FOR STORMS WILL BE OVER THE
SOUTHWEST QUADRANT OF THE AREA WHERE MODELS ALL AGREE THE 500MB
SHORT WAVE TROUGH WILL MOVE TONIGHT. FURTHER EAST AND NORTH THERE
IS LESS CONFIDENCE WHERE ELEVATED INSTABILITY IS HIGHER DUE TO A LACK OF
UPPER LEVEL FORCING TO GENERATE CONVECTION. HOWEVER BASED ON STORM
BEHAVIOR LAST NIGHT...ANY OUTFLOW BOUNDARIES MAY GENERATE FURTHER
CONVECTION DUE TO SOME ELEVATED CAPE PRESENT. DUE TO UNCERTAINTY
IN HOW CONVECTION WILL EVOLVE PAST MID EVENING...WILL LEAVE THE
CURRENT FORECAST AFTER THIS POINT AS IS AND UPDATE AS NEEDED.
&&
.SHORT TERM...(THIS AFTERNOON THROUGH SUNDAY)
ISSUED AT 131 PM MDT SAT JUL 26 2014
LATEST WV IMAGE AND RAP UPPER LEVEL ANALYSIS SHOW BROAD RIDGE STILL
IN PLACE FROM THE DESERT SOUTHWEST ACROSS THE SOUTHERN PLAINS AND
INTO THE SOUTHERN MISSISSIPPI VALLEY. A PLUME OF MONSOONAL MOISTURE
CONTINUES TO ROUND THE WESTERN AND NORTHERN PERIPHERY OF THIS RIDGE
INTO THE CENTRAL ROCKIES AND HIGH PLAINS. A CLOSED LOW IS CENTERED
OVER SOUTHERN MANITOBA CANADA WITH A SHORTWAVE TROUGH OUT AHEAD OF
THIS ENTERING THE NORTHERN MISSISSIPPI VALLEY. AT THE SURFACE LOW
PRESSURE IS IN PLACE OVER OUR CWA WITH SEVERAL WEAK CONVERGENT AREAS
ACROSS OUR SOUTH...AND A COLD FRONT ENTERING NORTHWEST KANSAS FROM
COLORADO AND SOUTHWEST NEBRASKA.
RAP ANALYSIS INDICATES MODERATE SB/MIXED LAYER CAPE VALUES AHEAD OF
MEAN SURFACE TROUGH AXIS ACROSS MOST OF OUR CWA. SHEER IS NOT
PARTICULARLY IMPRESSIVE...HOWEVER WITH SOUNDINGS SHOWING INVERTED V
TYPE SOUNDINGS AND DCAPE 1000 J/KG OR HIGHER MICROBURST POTENTIAL IS
THERE FOR ANY THUNDERSTORM ACTIVITY. GUIDANCE CONTINUES TO FAVOR THE
SOUTHERN PART OF OUR CWA FOR THUNDERSTORM COVERAGE...MAINLY ALONG
AND AHEAD OF COLD FRONT. WEAK FORCING ROTATING FROM THE NORTH
LATER THIS EVENING MAY ALSO SUPPORT ADDITIONAL POST FRONTAL
THUNDERSTORM DEVELOPMENT. POP ADJUSTMENTS WERE MADE TO REFLECT
THESE TRENDS THROUGH TONIGHT. SUBSIDENT AIR MASS APPEARS TO BE IN
PLACE OVER MOST OF THE CWA SUNDAY...THOUGH BY SUNDAY AFTERNOON
UPSLOPE COMBINED WITH OVERRUNNING ALONG STALLED FRONTAL ZONE IN
COLORADO MAY ALLOW FOR SHOWER/THUNDERSTORM DEVELOPMENT INTO THE SW
PART OF THE CWA IN THE AFTERNOON.
TEMPERATURES SATURDAY SHOULD BE COOLER...HOWEVER THERE IS QUITE A
BIT OF SPREAD DUE TO NAM/SREF LINGERING PRECIP MOST OF THE DAY
ACROSS MUCH OF THE CWA. I AM NOT FAVORING THIS SOLUTION AS BETTER
SUPPORT FOR SHOWER/THUNDERSTORM (AND ANY LOW CLOUD COVER) WOULD BE
FURTHER WEST AND SOUTHWEST. IF THE NAM/SREF WERE CORRECT THEN HIGHS
IN THE LOW 80S FOR WESTERN PARTS OF THE CWA. BASED ON THE FAVORED
WARMER SOLUTION WE SHOULD SEE HIGHS WARM TO NEAR NORMAL VALUES IN
THE UPPER 80S FOR A LOT OF THE CWA SUNDAY.
.LONG TERM...(SUNDAY NIGHT THROUGH SATURDAY)
ISSUED AT 232 PM MDT SAT JUL 26 2014
SUNDAY NIGHT THROUGH TUESDAY...FORECAST CONCERNS FOR THE PERIOD
INCLUDE COOLING TEMPERATURES AND PRECIPITATION CHANCES...MAINLY IN
THE SOUTHWESTERN PORTION OF THE CWA. NEAR TERM MODELS IN GENERAL
AGREEMENT WITH LARGE SCALE PATTERN AND ALL SUGGEST A MUCH COOLER
START TO THE WEEK THAN THE PAST WEEK.
CWA WILL FIND ITSELF ON THE NORTHEAST FRINGE OF PERSISTENT H5 RIDGE
OVER THE ROCKIES. DESPITE THE RIDGE POSITION...PERIODS OF ASCENT
ACROSS WILL PERIODICALLY DEVELOP AS NUMEROUS SMALL SCALE
DISTURBANCES AND PERSISTENT WEAK WAA REMAIN ACROSS WESTERN HALF OF
THE CWA. ALTHOUGH FORCING IS WEAK...DO NOT SEE ANY REASON WHY MID
LEVELS WILL DRY OUT DURING THE PERIOD AND WITH ELEVATED CAPE PRESENT
THROUGHOUT THINK WE WILL SEE SEVERAL PERIODS OF SHOWERS AND WEAK
THUNDERSTORMS. TRIED TO ADD SOME DIURNAL COMPONENT TO WX TIMING AS
THINK BEST CHANCES WILL BE GENERALLY IN THE OVERNIGHT HOURS AS
MODEST LOW LEVEL JET DEVELOPS TO AID IN MOISTURE ADVECTION/FORCED
ASCENT. GIVEN THE POSITION OF GREATER INSTABILITY AND OVERALL
PATTERN AM NOT EXPECTING LARGE PRECIPITATION AMOUNTS FOR THE PERIOD.
COLD FRONTAL PASSAGE COMBINED WITH PERSISTENT CLOUD COVER WILL
LIKELY LEAD TO MUCH COOLER TEMPERATURES FOR THE PERIOD...ABOUT 10 TO
20 DEGREES COOLER THAN PAST FEW DAYS.
IN THE EXTENDED(TUESDAY NIGHT-SATURDAY)...SIMILAR PATTERN TO
CONTINUE ACROSS TRI STATE AREA THROUGH THE END OF THE WEEK AS H5
RIDGE GRADUALLY AMPLIFIES IN RESPONSE TO TROUGHING DEVELOPING ACROSS
THE SOUTHEAST AND MIDWEST. GEFS AND OPERATIONAL MODELS CONTINUE TO
SUPPORT A HIGH PRECIP POTENTIAL ON TUESDAY NIGHT AND WEDNESDAY AS
MORE SIGNIFICANT SHORT WAVE TROUGH MOVES ACROSS THE AREA. MOISTURE
AND INSTABILITY SHOULD ALREADY BE IN PLACE WITH MAIN CONCERN BEING
HOW FAR NORTH/EAST PRECIP SHIELD WILL GO. STILL THINK BEST CHANCE
FOR RAIN WILL BE ACROSS SOUTHWESTERN CWA SO MADE ONLY MINOR CHANGES
HERE. OTHERWISE...COOLER TEMPERATURES AS A FEW CHANCES FOR LIGHT
PRECIPITATION ARE ANTICIPATED FOR THE PERIOD.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z SUNDAY EVENING)
ISSUED AT 540 PM MDT SAT JUL 26 2014
VFR CONDITIONS FORECAST FOR THE 0Z TAFS. THIS EVENING STORMS MAY
MOVE NEAR THE KGLD SITE. AM NOT TOO OPTIMISTIC SINCE STORMS SHOULD
REMAIN SOUTH OF THE SITE BUT DID KEEP THE MENTION IN SINCE IT WAS
IN THE PREVIOUS TAF. IN ADDITION ANY OUTFLOW BOUNDARIES MAY
GENERATE FURTHER CONVECTION WHICH IS VERY DIFFICULT TO PREDICT
BEFORE HAND SO A MENTION OF VCTS SEEMS FINE. OTHERWISE AS THE COLD
FRONT MOVES THROUGH OVERNIGHT CEILINGS WILL FALL TO NEAR MVFR FOR
A FEW HOURS AT KGLD.
FOR KMCK LIGHT NORTHERLY WINDS WILL PERSIST THROUGH THE PERIOD.
ANY STORMS THAT DEVELOP TONIGHT WILL REMAIN SOUTH OF THE SITE.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...HEAT ADVISORY UNTIL 8 PM CDT THIS EVENING FOR KSZ004-016.
CO...NONE.
NE...NONE.
&&
$$
UPDATE...JTL
SHORT TERM...DR
LONG TERM...JRM
AVIATION...JTL
AREA FORECAST DISCUSSION
NWS GOODLAND KS
506 PM MDT SAT JUL 26 2014
.UPDATE...
ISSUED AT 454 PM MDT SAT JUL 26 2014
INCREASED RAINFALL CHANCES OVER MAINLY EAST CENTRAL COLORADO AHEAD
OF THE STORMS MOVING OFF THE HIGHER TERRAIN FURTHER WEST. GENERAL
TREND WITH MODEL DATA HAS BEEN TO SLOW DOWN THE PROGRESSION OF THE
500MB SHORT WAVE TROUGH FOLLOWING THE STORMS. SOUNDINGS DO SHOW
ELEVATED CAPE...WITH THE MOST CAPE/LEAST CINH WHEN LIFTED FROM
700MB OR SO THIS EVENING. HOWEVER TREND IN DATA IS TO PLACE THE
BEST INSTABILITY JUST SOUTH OF THE AREA THEN BRING IT BACK NORTH
OVERNIGHT.
CURRENTLY AM THINKING THE BEST CHANCE FOR STORMS WILL BE OVER THE
SOUTHWEST QUADRANT OF THE AREA WHERE MODELS ALL AGREE THE 500MB
SHORT WAVE TROUGH WILL MOVE TONIGHT. FURTHER EAST AND NORTH THERE
IS LESS CONFIDENCE WHERE ELEVATED INSTABILITY IS HIGHER DUE TO A LACK OF
UPPER LEVEL FORCING TO GENERATE CONVECTION. HOWEVER BASED ON STORM
BEHAVIOR LAST NIGHT...ANY OUTFLOW BOUNDARIES MAY GENERATE FURTHER
CONVECTION DUE TO SOME ELEVATED CAPE PRESENT. DUE TO UNCERTAINTY
IN HOW CONVECTION WILL EVOLVE PAST MID EVENING...WILL LEAVE THE
CURRENT FORECAST AFTER THIS POINT AS IS AND UPDATE AS NEEDED.
&&
.SHORT TERM...(THIS AFTERNOON THROUGH SUNDAY)
ISSUED AT 131 PM MDT SAT JUL 26 2014
LATEST WV IMAGE AND RAP UPPER LEVEL ANALYSIS SHOW BROAD RIDGE STILL
IN PLACE FROM THE DESERT SOUTHWEST ACROSS THE SOUTHERN PLAINS AND
INTO THE SOUTHERN MISSISSIPPI VALLEY. A PLUME OF MONSOONAL MOISTURE
CONTINUES TO ROUND THE WESTERN AND NORTHERN PERIPHERY OF THIS RIDGE
INTO THE CENTRAL ROCKIES AND HIGH PLAINS. A CLOSED LOW IS CENTERED
OVER SOUTHERN MANITOBA CANADA WITH A SHORTWAVE TROUGH OUT AHEAD OF
THIS ENTERING THE NORTHERN MISSISSIPPI VALLEY. AT THE SURFACE LOW
PRESSURE IS IN PLACE OVER OUR CWA WITH SEVERAL WEAK CONVERGENT AREAS
ACROSS OUR SOUTH...AND A COLD FRONT ENTERING NORTHWEST KANSAS FROM
COLORADO AND SOUTHWEST NEBRASKA.
RAP ANALYSIS INDICATES MODERATE SB/MIXED LAYER CAPE VALUES AHEAD OF
MEAN SURFACE TROUGH AXIS ACROSS MOST OF OUR CWA. SHEER IS NOT
PARTICULARLY IMPRESSIVE...HOWEVER WITH SOUNDINGS SHOWING INVERTED V
TYPE SOUNDINGS AND DCAPE 1000 J/KG OR HIGHER MICROBURST POTENTIAL IS
THERE FOR ANY THUNDERSTORM ACTIVITY. GUIDANCE CONTINUES TO FAVOR THE
SOUTHERN PART OF OUR CWA FOR THUNDERSTORM COVERAGE...MAINLY ALONG
AND AHEAD OF COLD FRONT. WEAK FORCING ROTATING FROM THE NORTH
LATER THIS EVENING MAY ALSO SUPPORT ADDITIONAL POST FRONTAL
THUNDERSTORM DEVELOPMENT. POP ADJUSTMENTS WERE MADE TO REFLECT
THESE TRENDS THROUGH TONIGHT. SUBSIDENT AIR MASS APPEARS TO BE IN
PLACE OVER MOST OF THE CWA SUNDAY...THOUGH BY SUNDAY AFTERNOON
UPSLOPE COMBINED WITH OVERRUNNING ALONG STALLED FRONTAL ZONE IN
COLORADO MAY ALLOW FOR SHOWER/THUNDERSTORM DEVELOPMENT INTO THE SW
PART OF THE CWA IN THE AFTERNOON.
TEMPERATURES SATURDAY SHOULD BE COOLER...HOWEVER THERE IS QUITE A
BIT OF SPREAD DUE TO NAM/SREF LINGERING PRECIP MOST OF THE DAY
ACROSS MUCH OF THE CWA. I AM NOT FAVORING THIS SOLUTION AS BETTER
SUPPORT FOR SHOWER/THUNDERSTORM (AND ANY LOW CLOUD COVER) WOULD BE
FURTHER WEST AND SOUTHWEST. IF THE NAM/SREF WERE CORRECT THEN HIGHS
IN THE LOW 80S FOR WESTERN PARTS OF THE CWA. BASED ON THE FAVORED
WARMER SOLUTION WE SHOULD SEE HIGHS WARM TO NEAR NORMAL VALUES IN
THE UPPER 80S FOR A LOT OF THE CWA SUNDAY.
.LONG TERM...(SUNDAY NIGHT THROUGH SATURDAY)
ISSUED AT 232 PM MDT SAT JUL 26 2014
SUNDAY NIGHT THROUGH TUESDAY...FORECAST CONCERNS FOR THE PERIOD
INCLUDE COOLING TEMPERATURES AND PRECIPITATION CHANCES...MAINLY IN
THE SOUTHWESTERN PORTION OF THE CWA. NEAR TERM MODELS IN GENERAL
AGREEMENT WITH LARGE SCALE PATTERN AND ALL SUGGEST A MUCH COOLER
START TO THE WEEK THAN THE PAST WEEK.
CWA WILL FIND ITSELF ON THE NORTHEAST FRINGE OF PERSISTENT H5 RIDGE
OVER THE ROCKIES. DESPITE THE RIDGE POSITION...PERIODS OF ASCENT
ACROSS WILL PERIODICALLY DEVELOP AS NUMEROUS SMALL SCALE
DISTURBANCES AND PERSISTENT WEAK WAA REMAIN ACROSS WESTERN HALF OF
THE CWA. ALTHOUGH FORCING IS WEAK...DO NOT SEE ANY REASON WHY MID
LEVELS WILL DRY OUT DURING THE PERIOD AND WITH ELEVATED CAPE PRESENT
THROUGHOUT THINK WE WILL SEE SEVERAL PERIODS OF SHOWERS AND WEAK
THUNDERSTORMS. TRIED TO ADD SOME DIURNAL COMPONENT TO WX TIMING AS
THINK BEST CHANCES WILL BE GENERALLY IN THE OVERNIGHT HOURS AS
MODEST LOW LEVEL JET DEVELOPS TO AID IN MOISTURE ADVECTION/FORCED
ASCENT. GIVEN THE POSITION OF GREATER INSTABILITY AND OVERALL
PATTERN AM NOT EXPECTING LARGE PRECIPITATION AMOUNTS FOR THE PERIOD.
COLD FRONTAL PASSAGE COMBINED WITH PERSISTENT CLOUD COVER WILL
LIKELY LEAD TO MUCH COOLER TEMPERATURES FOR THE PERIOD...ABOUT 10 TO
20 DEGREES COOLER THAN PAST FEW DAYS.
IN THE EXTENDED(TUESDAY NIGHT-SATURDAY)...SIMILAR PATTERN TO
CONTINUE ACROSS TRI STATE AREA THROUGH THE END OF THE WEEK AS H5
RIDGE GRADUALLY AMPLIFIES IN RESPONSE TO TROUGHING DEVELOPING ACROSS
THE SOUTHEAST AND MIDWEST. GEFS AND OPERATIONAL MODELS CONTINUE TO
SUPPORT A HIGH PRECIP POTENTIAL ON TUESDAY NIGHT AND WEDNESDAY AS
MORE SIGNIFICANT SHORT WAVE TROUGH MOVES ACROSS THE AREA. MOISTURE
AND INSTABILITY SHOULD ALREADY BE IN PLACE WITH MAIN CONCERN BEING
HOW FAR NORTH/EAST PRECIP SHIELD WILL GO. STILL THINK BEST CHANCE
FOR RAIN WILL BE ACROSS SOUTHWESTERN CWA SO MADE ONLY MINOR CHANGES
HERE. OTHERWISE...COOLER TEMPERATURES AS A FEW CHANCES FOR LIGHT
PRECIPITATION ARE ANTICIPATED FOR THE PERIOD.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON)
ISSUED AT 1124 AM MDT SAT JUL 26 2014
VFR CONDITIONS SHOULD PREVAIL THROUGH THE TAF PERIOD AT KGLD AND
KMCK. MAIN AVIATION CONCERN WILL BE THUNDERSTORM ACTIVITY MAINLY
EXPECTED TO IMPACT LOCATIONS SOUTH OF INTERSTATE 70 AND KGLD. KEPT
VCTS MENTION IN KGLD TAF FOR THIS EVENING...AND LEFT MENTION OUT
OF KMCK. ADDITIONAL THUNDERSTORM ACTIVITY REDEVELOP OR
LINGER LATER TONIGHT...HOWEVER I FELT MOST CONFIDENT WITH THE
EVENING PERIOD AT THIS POINT. WINDS FROM THE NORTHWEST 10-15KT
WILL EVENTUALLY SHIFT TO THE NORTHEAST AS A SURFACE LOW MOVES
SOUTH...THEN A COLD FRONT WILL MOVE OVER BOTH TERMINALS THIS
EVENING AND THERE COULD BE A BRIEF PERIOD OF GUSTY WINDS FROM THE
NORTHEAST. AFTER 06Z NORTHEAST WINDS AROUND 10KT SHOULD PREVAIL
WITH FRONT SOUTH OF BOTH TERMINALS.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...HEAT ADVISORY UNTIL 8 PM CDT THIS EVENING FOR KSZ004-016.
CO...NONE.
NE...NONE.
&&
$$
UPDATE...JTL
SHORT TERM...DR
LONG TERM...JRM
AVIATION...DR
AREA FORECAST DISCUSSION
NWS GOODLAND KS
222 PM MDT FRI JUL 25 2014
.SHORT TERM...(THIS AFTERNOON THROUGH SATURDAY)
ISSUED AT 112 PM MDT FRI JUL 25 2014
EARLY AFTERNOON WV IMAGERY AND RAP UPPER LEVEL ANALYSIS SHOW BROAD
RIDGE STILL IN PLACE FROM THE DESERT SW ACROSS THE SOUTHERN
PLAINS...WITH A PLUME OF MID-UPPER LEVEL MOISTURE AND WEAK VORTICITY
ROTATING AROUND THE NORTHERN PERIPHERY OF THIS RIDGE ACROSS THE
CENTRAL ROCKIES INTO THE HIGH PLAINS. A CLOSED LOW IS MOVING ACROSS
SOUTHERN CANADA WITH SOME WEAK REFLECTION OF THIS EXTENDING FURTHER
SOUTH INTO THE NORTHERN PLAINS. AT THE SURFACE A WEAK COLD FRONT HAS
STALLED OVER THE SOUTHERN PART OF OUR CWA...WITH FAVORABLE JULY
SOLAR ANGLE SUPPORTING GOOD RADIATIONAL WARMING THIS AFTERNOON AS
HIGHS HAVE STILL REACHED THE MID TO UPPER 90S OVER MUCH OF THE CWA
(A LITTLE COOLER TOWARDS THE NW).
STALLED FRONT IN THE SOUTH COMBINED WITH ELEVATED TERRAIN IN
COLORADO SHOULD HELP INITIATE THUNDERSTORMS (WHICH HAVE ALREADY
DEVELOPED ALONG FRONT RANGE). HIGH LCL/LFC OVER OUR CWA SHOULD KEEP
THUNDERSTORM ACTIVITY ELEVATED AND WITH INCREASING INSTABILITY AND
DCAPE WOULD SUPPORT POTENTIAL FOR DOWNBURSTS. IF UPDRAFTS ARE STRONG
ENOUGH...MAYBE LARGE HAIL WOULD BE POSSIBLE THIS
AFTERNOON/EVENING...HOWEVER WITH VERY WARM LOW-MID LEVELS ABOVE
SHALLOW FRONTAL INVERSION CONDITIONS ARE MORE IN LINE WITH A WIND
THREAT. GUIDANCE CONTINUES TO SHOW BETTER COVERAGE OVER
CWA...HOWEVER DESPITE GOOD SURFACE-BL MOISTURE ALONG FRONTAL ZONE
AIR MASS ITSELF IS FAIRLY DRY AND COVERAGE IS A QUESTION. BEST
FORCING WOULD ACTUALLY BE LATER IN THE EVENING AS SHORTWAVE (ALONG
WITH POSSIBLE OUTFLOW FROM POSSIBLE MCS IN THE NORTH) MOVES INTO THE
CWA. AT THIS POINT I WAS COMFORTABLE KEEPING COVERAGE ISOLATED AND
DELAYED EXIT UNTIL AFTER 06Z. WILL NEED TO MONITOR TRENDS AS WESTERN
LOCATIONS COULD SEE SLIGHTLY BETTER COVERAGE BEFORE SUNSET.
DEEPENING ON EVOLUTION OF OUTFLOW (AS INDICATED BY NAM) OR WEAK
FRONTAL PASSAGE SATURDAY TEMPS COULD BE TRICKY ONCE AGAIN AS HEIGHTS
AND PATTERN ALOFT WOULD GENERALLY SUPPORT GOOD DAYTIME HEATING AND A
RECOVERY OF THE AIR MASS IN PLACE. I KEPT TEMPS SIMILAR TO TODAY
WITH ABOVE NORMAL VALUES IN THE 90S (AROUND 100F IN THE EAST). HIGH
BASED THUNDERSTORMS MAY DEVELOP AGAIN SATURDAY AFTERNOON ALONG
FRONTAL ZONE IN THE SOUTH...HOWEVER CONFIDENCE IS LOW ON EARLIER
INITIATION OVER OUR CWA...WITH FLOW MORE SUPPORTIVE OF UPSTREAM
DEVELOPMENT IN COLORADO.
.LONG TERM...(SATURDAY NIGHT THROUGH FRIDAY)
ISSUED AT 220 PM MDT FRI JUL 25 2014
UPPER FLOW TRANSITIONS FROM ZONAL TO NORTHWESTERLY IN THE SUN-MON
TIME FRAME...WHICH THEN CONTINUES THROUGH THE REST OF THE WEEK.
AT THE SURFACE...A REINFORCING SHOT OF COOLER AIR DROPS DOWN SATURDAY
NIGHT WHICH PUSHES THE SURFACE FRONT WELL SOUTH OF THE FORECAST
AREA. AS A RESULT...MUCH OF THE PRECIPITATION POTENTIAL EARLY ON
WILL BE SOUTH AND WEST OF THE CWA. THE BEST WINDOW FOR THUNDERSTORMS
IN THE EXTENDED PERIOD WILL BE TUE NIGHT-WED NIGHT WHEN THE EC/GFS
BOTH GENERATE AN EXTENSIVE AREA OF PRECIPITATION WHICH MOVES
SOUTHEAST ACROSS THE REGION AS A SHORT WAVE TROUGH DROPS THROUGH
THE FLOW.
THE PRESENCE OF A CANADIAN AIRMASS WHICH DOMINATES THE ENTIRE WEEK
WILL PROVIDE RELIEF FROM THE RECENT STRETCH OF HOT WEATHER. 850 MB
TEMPERATURES ARE FORECAST TO REMAIN IN THE 22-25C RANGE THROUGH
NEXT WEEKEND...WHICH TRANSLATES TO LOW-MID 80S FOR HIGHS. THE
COOLEST DAY WILL BE WEDNESDAY GIVEN THE LIKELY PRESENCE OF CLOUDS
AND SCATTERED SHOWERS AND THUNDERSTORMS. DEPENDING ON CLOUD COVER
THERE IS POTENTIAL FOR SOME AREAS TO REMAIN IN THE UPPER 70S WED.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON)
ISSUED AT 1106 AM MDT FRI JUL 25 2014
VFR CONDITIONS WILL PREVAIL AT BOTH KGLD AND KMCK THROUGH THE TAF
PERIOD. NW WINDS AROUND 10-15KT GUSTING TO AROUND 20KT WILL
CONTINUE THROUGH THE EARLY PART OF THE TAF PERIOD BEHIND A COLD
FRONT JUST SOUTH OF BOTH TERMINALS. BETTER CHANCE FOR GUSTS WILL
BE AT KGLD. BY MID AFTERNOON THE SURFACE GRADIENT WILL RELAX AND
AS A RESULT WIND SPEED WILL DROP TO 10KT OR LESS SHIFTING TO THE
NORTHEAST THEN SOUTHEAST. THERE WILL BE ANOTHER INCREASE IN WINDS
FROM THE NW MID-MORNING SATURDAY FROM THE WEST...HOWEVER GUSTY
WINDS SHOULD HOLD OFF DURING THIS TAF PERIOD SATURDAY.
ISOLATED THUNDERSTORMS WILL DEVELOP LATE THIS AFTERNOON THROUGH
THE EVENING HOURS MAINLY OVER EASTERN COLORADO AND NW KANSAS.
COVERAGE IS A BIG QUESTION AT THIS POINT...SO I AM LEAVING MENTION
OUT OF BOTH KGLD AND KMCK. WE MAY END UP NEEDING TO ADD VCTS AT
KGLD IF COVERAGE IS A LITTLE BETTER THAN CURRENTLY ANTICIPATED.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
SHORT TERM...DR
LONG TERM...DLF
AVIATION...DR
AREA FORECAST DISCUSSION
NWS GOODLAND KS
113 PM MDT FRI JUL 25 2014
.SHORT TERM...(THIS AFTERNOON THROUGH SATURDAY)
ISSUED AT 112 PM MDT FRI JUL 25 2014
EARLY AFTERNOON WV IMAGERY AND RAP UPPER LEVEL ANALYSIS SHOW BROAD
RIDGE STILL IN PLACE FROM THE DESERT SW ACROSS THE SOUTHERN
PLAINS...WITH A PLUME OF MID-UPPER LEVEL MOISTURE AND WEAK VORTICITY
ROTATING AROUND THE NORTHERN PERIPHERY OF THIS RIDGE ACROSS THE
CENTRAL ROCKIES INTO THE HIGH PLAINS. A CLOSED LOW IS MOVING ACROSS
SOUTHERN CANADA WITH SOME WEAK REFLECTION OF THIS EXTENDING FURTHER
SOUTH INTO THE NORTHERN PLAINS. AT THE SURFACE A WEAK COLD FRONT HAS
STALLED OVER THE SOUTHERN PART OF OUR CWA...WITH FAVORABLE JULY
SOLAR ANGLE SUPPORTING GOOD RADIATIONAL WARMING THIS AFTERNOON AS
HIGHS HAVE STILL REACHED THE MID TO UPPER 90S OVER MUCH OF THE CWA
(A LITTLE COOLER TOWARDS THE NW).
STALLED FRONT IN THE SOUTH COMBINED WITH ELEVATED TERRAIN IN
COLORADO SHOULD HELP INITIATE THUNDERSTORMS (WHICH HAVE ALREADY
DEVELOPED ALONG FRONT RANGE). HIGH LCL/LFC OVER OUR CWA SHOULD KEEP
THUNDERSTORM ACTIVITY ELEVATED AND WITH INCREASING INSTABILITY AND
DCAPE WOULD SUPPORT POTENTIAL FOR DOWNBURSTS. IF UPDRAFTS ARE STRONG
ENOUGH...MAYBE LARGE HAIL WOULD BE POSSIBLE THIS
AFTERNOON/EVENING...HOWEVER WITH VERY WARM LOW-MID LEVELS ABOVE
SHALLOW FRONTAL INVERSION CONDITIONS ARE MORE IN LINE WITH A WIND
THREAT. GUIDANCE CONTINUES TO SHOW BETTER COVERAGE OVER
CWA...HOWEVER DESPITE GOOD SURFACE-BL MOISTURE ALONG FRONTAL ZONE
AIR MASS ITSELF IS FAIRLY DRY AND COVERAGE IS A QUESTION. BEST
FORCING WOULD ACTUALLY BE LATER IN THE EVENING AS SHORTWAVE (ALONG
WITH POSSIBLE OUTFLOW FROM POSSIBLE MCS IN THE NORTH) MOVES INTO THE
CWA. AT THIS POINT I WAS COMFORTABLE KEEPING COVERAGE ISOLATED AND
DELAYED EXIT UNTIL AFTER 06Z. WILL NEED TO MONITOR TRENDS AS WESTERN
LOCATIONS COULD SEE SLIGHTLY BETTER COVERAGE BEFORE SUNSET.
DEEPENING ON EVOLUTION OF OUTFLOW (AS INDICATED BY NAM) OR WEAK
FRONTAL PASSAGE SATURDAY TEMPS COULD BE TRICKY ONCE AGAIN AS HEIGHTS
AND PATTERN ALOFT WOULD GENERALLY SUPPORT GOOD DAYTIME HEATING AND A
RECOVERY OF THE AIR MASS IN PLACE. I KEPT TEMPS SIMILAR TO TODAY
WITH ABOVE NORMAL VALUES IN THE 90S (AROUND 100F IN THE EAST). HIGH
BASED THUNDERSTORMS MAY DEVELOP AGAIN SATURDAY AFTERNOON ALONG
FRONTAL ZONE IN THE SOUTH...HOWEVER CONFIDENCE IS LOW ON EARLIER
INITIATION OVER OUR CWA...WITH FLOW MORE SUPPORTIVE OF UPSTREAM
DEVELOPMENT IN COLORADO.
.LONG TERM...(MONDAY THROUGH THURSDAY)
ISSUED AT 206 AM MDT FRI JUL 25 2014
FOR THE EXTENDED PERIOD...NO MAJOR CHANGES IN LATEST MODEL RUNS FOR
OVERALL UPPER LEVEL PATTERN. GOING INTO NEXT MONDAY...BROAD H5/H7
RIDGE OVER THE WESTERN PORTION OF THE COUNTRY...AND A DEEP MID LEVEL
TROUGH OVER THE EASTERN PORTION OF THE COUNTRY. THIS LEAVES THE
FORECAST AREA IN BETWEEN THE TWO SYSTEMS FOR THE ENTIRE 4-DAY
PERIOD. AT THE SURFACE...BOUNDARY STAYS ALONG THE EAST COAST...DOWN
INTO THE GULF REGION AND UP INTO THE CENTRAL PLAINS. MONDAY AND
TUESDAY HAS CWA SEEING LOW PRESSURE FORM ALONG THE TAIL-END OF THE
FRONT IN EASTERN COLORADO. WITH LITTLE FORCING TO MOVE CONVECTION
THAT DEVELOPS...KEEPING HEAVIEST CONCENTRATION OF PRECIPITATION OVER
WESTERN PORTIONS OF THE FORECAST AREA.
BY MIDWEEK...WEAK 700 MB SHORTWAVE MOVES OFF THE FRONT RANGE AND
ALONG THE FRONTAL BOUNDARY SLIDING TO OUR SOUTH THROUGH THE DAY INTO
THE EVENING HOURS. MODEL TRACK WILL PUT HIGHEST POP CHANCES ALONG
WESTERN/SOUTHERN ZONES BEFORE TAPERING OFF. BRIEF RESPITE IN
CONVECTIVE ACTIVITY OVERNIGHT WEDNESDAY AS SURFACE RIDGING OCCURS
INTO THURSDAY MORNING. GOING INTO THURSDAY...TROUGH TO THE EAST DOES
RETROGRADE SOME...HINTING THAT CUTOFF LOW MAY FORM. SEVERAL
SHORTWAVES WILL THEN PINWHEEL SOUTH ON BACKSIDE OF THIS SYSTEM...
ALLOWING FOR 20-30 POP POTENTIAL FOR RW/TRW THURSDAY...DROPPING OFF
THURSDAY NIGHT AND THEN RETURNING FOR FRIDAY. WITH REGION SEEING
BROAD NW THROUGH THE EXTENDED TIMEFRAME...COMBINED WITH FRONTAL
BOUNDARY LOCATED JUST TO OUR SOUTH AND CLOUD COVER FROM EXPECTED
CONVECTION...LOOKING FOR TEMPERATURES TO RANGE A FEW DEGREES BELOW
NORMAL FOR BOTH HIGHS(LOW TO MID 80S)/LOWS(LOW TO MID 60S).
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON)
ISSUED AT 1106 AM MDT FRI JUL 25 2014
VFR CONDITIONS WILL PREVAIL AT BOTH KGLD AND KMCK THROUGH THE TAF
PERIOD. NW WINDS AROUND 10-15KT GUSTING TO AROUND 20KT WILL
CONTINUE THROUGH THE EARLY PART OF THE TAF PERIOD BEHIND A COLD
FRONT JUST SOUTH OF BOTH TERMINALS. BETTER CHANCE FOR GUSTS WILL
BE AT KGLD. BY MID AFTERNOON THE SURFACE GRADIENT WILL RELAX AND
AS A RESULT WIND SPEED WILL DROP TO 10KT OR LESS SHIFTING TO THE
NORTHEAST THEN SOUTHEAST. THERE WILL BE ANOTHER INCREASE IN WINDS
FROM THE NW MID-MORNING SATURDAY FROM THE WEST...HOWEVER GUSTY
WINDS SHOULD HOLD OFF DURING THIS TAF PERIOD SATURDAY.
ISOLATED THUNDERSTORMS WILL DEVELOP LATE THIS AFTERNOON THROUGH
THE EVENING HOURS MAINLY OVER EASTERN COLORADO AND NW KANSAS.
COVERAGE IS A BIG QUESTION AT THIS POINT...SO I AM LEAVING MENTION
OUT OF BOTH KGLD AND KMCK. WE MAY END UP NEEDING TO ADD VCTS AT
KGLD IF COVERAGE IS A LITTLE BETTER THAN CURRENTLY ANTICIPATED.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
SHORT TERM...DR
LONG TERM...JN
AVIATION...DR
AREA FORECAST DISCUSSION
NWS JACKSON KY
1152 PM EDT SAT JUL 26 2014
.UPDATE...
ISSUED AT 1151 PM EDT SAT JUL 26 2014
THE MCS IS WEAKENING TO THE WEST OVER CENTRAL KENTUCKY. IN DISCUSSION
WITH SPC...DECIDED NOT TO EXTEND THE WATCH INTO EASTERN KENTUCKY AS
THE STORMS ARE SHOWING A WEAKENING TREND. THERE ARE TWO STORMS WE
ARE WATCHING. ONE IS THE STORM MOVING INTO CASEY COUNTY AND THE
OTHER ONE IS OVER OWEN COUNTY. EXPECT THE LINE OF SHOWERS TO MOVE
ACROSS THE EASTERN KENTUCKY DURING THE OVERNIGHT HOURS. THERE IS
STILL A REMOTE POSSIBILITY OF GETTING A STORM CAPABLE OF PRODUCING
WIND DAMAGE...BUT THEY SHOULD BE FEW AND FAR BETWEEN. THE REST OF THE
FORECAST IS ON TRACK.
UPDATE ISSUED AT 1023 PM EDT SAT JUL 26 2014
UPDATED THE FORECAST TO BETTER REFLECT THE TIMING OF THE MCS MOVING
TOWARD THE AREA. THE LAST FEW SCANS...ON THE RADAR...THE MCS
APPROACHING FROM THE WEST IS TENDING TO DIVE TO THE SOUTH. THE
STRONGEST PORTION OF THE SYSTEM MAY JUST EFFECT THE AREA OF EASTERN
KENTUCKY WEST OF I-75. THE HIGHER THETA E VALUES ARE TO THE WEST OF
THE AREA...SO THIS BEHAVIOR AND MOVEMENT OF THE SYSTEM MAKES SENSE.
THE HRRR IS INDICATING THAT THE ST ROMS WILL WEAKEN AS THEY GET TO
EASTERN KENTUCKY. THE BIG SHOW IS STILL TOMORROW AFTERNOON. THE
COMBINATION OF ALL OF THE SEVERE PARAMETERS IS SOMETHING RARELY SEEN
IN EASTERN KENTUCKY IN JULY. WE WILL HAVE ENHANCED STAFFING AT THE
WEATHER OFFICE TOMORROW IN ANTICIPATION OF THE POTENTIAL SEVERE
THUNDERSTORMS TOMORROW AFTERNOON.
&&
.SHORT TERM...(THIS EVENING THROUGH SUNDAY NIGHT)
ISSUED AT 242 PM EDT SAT JUL 26 2014
DYNAMIC SITUATION UNFOLDING OVER THE NEXT 24 TO 36 HOURS AS A DEEP
TROUGH ALOFT DIVES INTO THE OHIO VALLEY. A STRONG COLD FRONT WILL
DROP SOUTHEAST INTO THE REGION SUPPLANTING WHAT WILL BECOME A VERY
WARM AND VERY MOIST AIRMASS IN PLACE ACROSS OUR REGION. THIS
COMBINATION OF A SPRING-TIME SETUP ALOFT COMBINED WITH SUMMER-TIME
HEAT AND HUMIDITY WILL CREATE CONDITIONS FAVORABLE FOR A SIGNIFICANT
SEVERE WEATHER OUTBREAK ON SUNDAY.
MODELS CONTINUE TO INDICATE A THUNDERSTORM COMPLEX WILL ORGANIZE TO
OUR WEST THIS AFTERNOON AND EVENING. THIS APPEARS TO BE HAPPENING
OVER MISSOURI AT THIS TIME. THESE STORMS SHOULD MARCH EASTWARD INTO
THE OVERNIGHT HOURS LIKELY ENDING UP SOMEWHERE OVER SOUTHERN INDIANA
AND NORTHERN KENTUCKY BY OR SHORTLY AFTER MIDNIGHT. THIS COMPLEX
SHOULD BE WEAKENING AS IT ENTERS OUR FORECAST AREA AFTER
MIDNIGHT...BUT CANNOT RULE OUT THE THREAT FOR DAMAGING WINDS AS IT
CROSSES THE REGION. THIS THREAT WOULD BE GREATEST FROM JKL AND
POINTS TO THE NORTH.
THE GREATER SEVERE WEATHER THREAT CONTINUES TO BE THE ANTICIPATED
SECOND ROUND OF THUNDERSTORMS EXPECTED TO ERUPT OVER US OR JUST TO
OUR NORTH SUNDAY AFTERNOON. PROVIDED EARLY MORNING CONVECTION GETS
OUT OF THE WAY IN TIME AND ATMOSPHERE DESTABILIZES AS PROJECTED...
THESE STORMS COULD BE QUITE STRONG. SOUNDINGS TOMORROW AFTERNOON ARE
IMPRESSIVE. STORM RELATIVE HELICITY VALUES EXCEED 300 M2/S2 COMBINED
WITH CAPE PROGGED TO EXCEED 3000 J/KG AND LCLS AROUND 3000 FT MSL.
IF THESE CONDITIONS VERIFY...A RARE JULY TORNADO OUTBREAK COULD
OCCUR. STILL...LOTS OF UNCERTAINTY WITH HOW TONIGHTS ACTIVITY WILL
PAN OUT AND HOW THIS WILL AFFECT OUR CONDITIONS ON SUNDAY BUT WILL
CONTINUE TO PLAY UP THE SEVERE WEATHER POTENTIAL IN OUR SUITE OF
PRODUCTS.
IN ADDITION TO THE SEVERE WEATHER CONCERNS...ISOLATED FLASH FLOODING
IS A CONCERN PRIMARILY ON SUNDAY. MOISTURE POOLING IN ADVANCE OF THE
FRONT WILL PUSH SURFACE DEWPOINTS INTO THE LOW TO MID 70S AND PWATS
WILL JUMP TO 1.75 INCHES AND ABOVE. STORM MOTIONS LOOK FAST ENOUGH
TO PRECLUDE A WIDESPREAD FLASH FLOODING THREAT...BUT AGAIN THAT WILL
DEPEND LARGELY ON HOW PRIMED WE GET BY TONIGHTS CONVECTION. NO FLASH
FLOOD WATCH WILL BE ISSUED AT THIS TIME...BUT THAT MAY NEED TO BE
REVISITED SHOULD THE INITIAL ROUND OF CONVECTION SATURATE THE GROUND
TONIGHT.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 242 PM EDT SAT JUL 26 2014
AN ANOMALOUS LARGE AND DEEP UPPER TROUGH WILL PERSIST OVER THE
EASTERN CONUS THROUGH THE PERIOD. THE SURFACE COLD FRONT MARKING THE
LEADING EDGE OF THE UNSEASONABLY COOL AIR MASS UNDER THE TROUGH WILL
BE WELL TO OUR SOUTHEAST ALREADY AS THE PERIOD STARTS...BUT RESIDUAL
LOW LEVEL MOISTURE WILL STILL BE MIXING VERTICALLY INTO THE NEW AIR
MASS AS COOLING ALOFT OCCURS. THIS MAY RESULT IN A FEW SHOWERS OR
THUNDERSTORMS MONDAY AFTERNOON OR EVENING...ESPECIALLY IN OUR NE
COUNTIES WHERE COOLER MID LEVEL TEMPS ARE EXPECTED.
ON TUESDAY...DRIER SURFACE AIR AND A MID LEVEL CAP SHOULD KEEP
CONVECTIVE CURRENTS BELOW ABOUT 10K FEET. SOME LIQUID COULD STILL
TRY TO FALL OUT OF THE CLOUDS...BUT WITH LIMITED CLOUD DEPTH AND
DRIER AIR...WILL ONLY MENTION SPRINKLES IN THE FORECAST.
A COOL AND DRY AIR MASS FIRMLY IN PLACE...COUPLED WITH A CESSATION OF
COOLING ALOFT...WILL ALLOW FOR MAINLY CLEAR SKIES FROM TUESDAY NIGHT
THROUGH THURSDAY NIGHT. NEAR RECORD LOW TEMPS WILL BE A POSSIBILITY.
AS THE HIGHLY AMPLIFIED UPPER TROUGH WEAKENS AT THE END OF THE
WEEK...MODELS AGREE ON ITS AXIS RETROGRADING TO THE WEST AS A LOW
CLOSES OFF. WITH THE LOW/TROUGH AXIS SLIPPING TO OUR WEST...WE WILL
RETURN TO ITS EAST SIDE WHICH IS SYNOPTICALLY MORE FAVORABLE FOR
PRECIP. FLOW FROM THE GULF OF MEXICO WILL STILL BE CUT OFF AND LOW
LEVEL MOISTURE WILL BE SLOW TO INCREASE...SO WILL ONLY USE LOW POPS.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z SUNDAY EVENING)
ISSUED AT 1023 PM EDT SAT JUL 26 2014
VFR CONDITIONS ARE ANTICIPATED THROUGH THE FIRST HALF OF THE TAF
PERIOD WITH LIGHT WINDS.
UPDATED THE FORECAST TO BETTER REFLECT THE TIMING OF THE MCS MOVING
TOWARD THE AREA. THE LAST FEW SCANS...ON THE RADAR...THE MCS
APPROACHING FROM THE WEST IS TENDING TO DIVE TO THE SOUTH. THE
STRONGEST PORTION OF THE SYSTEM MAY JUST EFFECT THE AREA OF EASTERN
KENTUCKY WEST OF I-75. THE HIGHER THETA E VALUES ARE TO THE WEST OF
THE AREA...SO THIS BEHAVIOR AND MOVEMENT OF THE SYSTEM MAKES SENSE.
THE HRRR IS INDICATING THAT THE ST ROMS WILL WEAKEN AS THEY GET TO
EASTERN KENTUCKY. THE BIG SHOW IS STILL TOMORROW AFTERNOON. THE
COMBINATION OF ALL OF THE SEVERE PARAMETERS IS SOMETHING RARELY SEEN
IN EASTERN KENTUCKY IN JULY. WE WILL HAVE ENHANCED STAFFING AT THE
WEATHER OFFICE TOMORROW IN ANTICIPATION OF THE POTENTIAL SEVERE
THUNDERSTORMS TOMORROW AFTERNOON. EXPECTING MOSTLY MVFR CIGS AND
VSBY FOR THE AREA...HOWEVER SOME OF STRONGER STORMS COULD BE CAPABLE
OF DROPPING THE VSBY TO AROUND A MILE AND PRODUCE WIND GUSTS OF 40
TO 50 KTS. THIS IS MORE LIKELY TO OCCUR WITH STORMS DURING THE
AFTERNOON. PUT TWO TEMPO GROUPS IN THE TAFS TO REFLECT THE MOST
LIKELY TIMES THAT THE STORMS WILL BE IN THE AREA...HOWEVER
THUNDERSTORMS ARE POSSIBLE ANYTIME AFTER ABOUT 5Z.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...JJ
SHORT TERM...ABE
LONG TERM...HAL
AVIATION...JJ
AREA FORECAST DISCUSSION
NWS JACKSON KY
1036 PM EDT SAT JUL 26 2014
.UPDATE...
ISSUED AT 1023 PM EDT SAT JUL 26 2014
UPDATED THE FORECAST TO BETTER REFLECT THE TIMING OF THE MCS MOVING
TOWARD THE AREA. THE LAST FEW SCANS...ON THE RADAR...THE MCS
APPROACHING FROM THE WEST IS TENDING TO DIVE TO THE SOUTH. THE
STRONGEST PORTION OF THE SYSTEM MAY JUST EFFECT THE AREA OF EASTERN
KENTUCKY WEST OF I-75. THE HIGHER THETA E VALUES ARE TO THE WEST OF
THE AREA...SO THIS BEHAVIOR AND MOVEMENT OF THE SYSTEM MAKES SENSE.
THE HRRR IS INDICATING THAT THE ST ROMS WILL WEAKEN AS THEY GET TO
EASTERN KENTUCKY. THE BIG SHOW IS STILL TOMORROW AFTERNOON. THE
COMBINATION OF ALL OF THE SEVERE PARAMETERS IS SOMETHING RARELY SEEN
IN EASTERN KENTUCKY IN JULY. WE WILL HAVE ENHANCED STAFFING AT THE
WEATHER OFFICE TOMORROW IN ANTICIPATION OF THE POTENTIAL SEVERE
THUNDERSTORMS TOMORROW AFTERNOON.
&&
.SHORT TERM...(THIS EVENING THROUGH SUNDAY NIGHT)
ISSUED AT 242 PM EDT SAT JUL 26 2014
DYNAMIC SITUATION UNFOLDING OVER THE NEXT 24 TO 36 HOURS AS A DEEP
TROUGH ALOFT DIVES INTO THE OHIO VALLEY. A STRONG COLD FRONT WILL
DROP SOUTHEAST INTO THE REGION SUPPLANTING WHAT WILL BECOME A VERY
WARM AND VERY MOIST AIRMASS IN PLACE ACROSS OUR REGION. THIS
COMBINATION OF A SPRING-TIME SETUP ALOFT COMBINED WITH SUMMER-TIME
HEAT AND HUMIDITY WILL CREATE CONDITIONS FAVORABLE FOR A SIGNIFICANT
SEVERE WEATHER OUTBREAK ON SUNDAY.
MODELS CONTINUE TO INDICATE A THUNDERSTORM COMPLEX WILL ORGANIZE TO
OUR WEST THIS AFTERNOON AND EVENING. THIS APPEARS TO BE HAPPENING
OVER MISSOURI AT THIS TIME. THESE STORMS SHOULD MARCH EASTWARD INTO
THE OVERNIGHT HOURS LIKELY ENDING UP SOMEWHERE OVER SOUTHERN INDIANA
AND NORTHERN KENTUCKY BY OR SHORTLY AFTER MIDNIGHT. THIS COMPLEX
SHOULD BE WEAKENING AS IT ENTERS OUR FORECAST AREA AFTER
MIDNIGHT...BUT CANNOT RULE OUT THE THREAT FOR DAMAGING WINDS AS IT
CROSSES THE REGION. THIS THREAT WOULD BE GREATEST FROM JKL AND
POINTS TO THE NORTH.
THE GREATER SEVERE WEATHER THREAT CONTINUES TO BE THE ANTICIPATED
SECOND ROUND OF THUNDERSTORMS EXPECTED TO ERUPT OVER US OR JUST TO
OUR NORTH SUNDAY AFTERNOON. PROVIDED EARLY MORNING CONVECTION GETS
OUT OF THE WAY IN TIME AND ATMOSPHERE DESTABILIZES AS PROJECTED...
THESE STORMS COULD BE QUITE STRONG. SOUNDINGS TOMORROW AFTERNOON ARE
IMPRESSIVE. STORM RELATIVE HELICITY VALUES EXCEED 300 M2/S2 COMBINED
WITH CAPE PROGGED TO EXCEED 3000 J/KG AND LCLS AROUND 3000 FT MSL.
IF THESE CONDITIONS VERIFY...A RARE JULY TORNADO OUTBREAK COULD
OCCUR. STILL...LOTS OF UNCERTAINTY WITH HOW TONIGHTS ACTIVITY WILL
PAN OUT AND HOW THIS WILL AFFECT OUR CONDITIONS ON SUNDAY BUT WILL
CONTINUE TO PLAY UP THE SEVERE WEATHER POTENTIAL IN OUR SUITE OF
PRODUCTS.
IN ADDITION TO THE SEVERE WEATHER CONCERNS...ISOLATED FLASH FLOODING
IS A CONCERN PRIMARILY ON SUNDAY. MOISTURE POOLING IN ADVANCE OF THE
FRONT WILL PUSH SURFACE DEWPOINTS INTO THE LOW TO MID 70S AND PWATS
WILL JUMP TO 1.75 INCHES AND ABOVE. STORM MOTIONS LOOK FAST ENOUGH
TO PRECLUDE A WIDESPREAD FLASH FLOODING THREAT...BUT AGAIN THAT WILL
DEPEND LARGELY ON HOW PRIMED WE GET BY TONIGHTS CONVECTION. NO FLASH
FLOOD WATCH WILL BE ISSUED AT THIS TIME...BUT THAT MAY NEED TO BE
REVISITED SHOULD THE INITIAL ROUND OF CONVECTION SATURATE THE GROUND
TONIGHT.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 242 PM EDT SAT JUL 26 2014
AN ANOMALOUS LARGE AND DEEP UPPER TROUGH WILL PERSIST OVER THE
EASTERN CONUS THROUGH THE PERIOD. THE SURFACE COLD FRONT MARKING THE
LEADING EDGE OF THE UNSEASONABLY COOL AIR MASS UNDER THE TROUGH WILL
BE WELL TO OUR SOUTHEAST ALREADY AS THE PERIOD STARTS...BUT RESIDUAL
LOW LEVEL MOISTURE WILL STILL BE MIXING VERTICALLY INTO THE NEW AIR
MASS AS COOLING ALOFT OCCURS. THIS MAY RESULT IN A FEW SHOWERS OR
THUNDERSTORMS MONDAY AFTERNOON OR EVENING...ESPECIALLY IN OUR NE
COUNTIES WHERE COOLER MID LEVEL TEMPS ARE EXPECTED.
ON TUESDAY...DRIER SURFACE AIR AND A MID LEVEL CAP SHOULD KEEP
CONVECTIVE CURRENTS BELOW ABOUT 10K FEET. SOME LIQUID COULD STILL
TRY TO FALL OUT OF THE CLOUDS...BUT WITH LIMITED CLOUD DEPTH AND
DRIER AIR...WILL ONLY MENTION SPRINKLES IN THE FORECAST.
A COOL AND DRY AIR MASS FIRMLY IN PLACE...COUPLED WITH A CESSATION OF
COOLING ALOFT...WILL ALLOW FOR MAINLY CLEAR SKIES FROM TUESDAY NIGHT
THROUGH THURSDAY NIGHT. NEAR RECORD LOW TEMPS WILL BE A POSSIBILITY.
AS THE HIGHLY AMPLIFIED UPPER TROUGH WEAKENS AT THE END OF THE
WEEK...MODELS AGREE ON ITS AXIS RETROGRADING TO THE WEST AS A LOW
CLOSES OFF. WITH THE LOW/TROUGH AXIS SLIPPING TO OUR WEST...WE WILL
RETURN TO ITS EAST SIDE WHICH IS SYNOPTICALLY MORE FAVORABLE FOR
PRECIP. FLOW FROM THE GULF OF MEXICO WILL STILL BE CUT OFF AND LOW
LEVEL MOISTURE WILL BE SLOW TO INCREASE...SO WILL ONLY USE LOW POPS.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z SUNDAY EVENING)
ISSUED AT 1023 PM EDT SAT JUL 26 2014
VFR CONDITIONS ARE ANTICIPATED THROUGH THE FIRST HALF OF THE TAF
PERIOD WITH LIGHT WINDS.
UPDATED THE FORECAST TO BETTER REFLECT THE TIMING OF THE MCS MOVING
TOWARD THE AREA. THE LAST FEW SCANS...ON THE RADAR...THE MCS
APPROACHING FROM THE WEST IS TENDING TO DIVE TO THE SOUTH. THE
STRONGEST PORTION OF THE SYSTEM MAY JUST EFFECT THE AREA OF EASTERN
KENTUCKY WEST OF I-75. THE HIGHER THETA E VALUES ARE TO THE WEST OF
THE AREA...SO THIS BEHAVIOR AND MOVEMENT OF THE SYSTEM MAKES SENSE.
THE HRRR IS INDICATING THAT THE ST ROMS WILL WEAKEN AS THEY GET TO
EASTERN KENTUCKY. THE BIG SHOW IS STILL TOMORROW AFTERNOON. THE
COMBINATION OF ALL OF THE SEVERE PARAMETERS IS SOMETHING RARELY SEEN
IN EASTERN KENTUCKY IN JULY. WE WILL HAVE ENHANCED STAFFING AT THE
WEATHER OFFICE TOMORROW IN ANTICIPATION OF THE POTENTIAL SEVERE
THUNDERSTORMS TOMORROW AFTERNOON. EXPECTING MOSTLY MVFR CIGS AND
VSBY FOR THE AREA...HOWEVER SOME OF STRONGER STORMS COULD BE CAPABLE
OF DROPPING THE VSBY TO AROUND A MILE AND PRODUCE WIND GUSTS OF 40
TO 50 KTS. THIS IS MORE LIKELY TO OCCUR WITH STORMS DURING THE
AFTERNOON. PUT TWO TEMPO GROUPS IN THE TAFS TO REFLECT THE MOST
LIKELY TIMES THAT THE STORMS WILL BE IN THE AREA...HOWEVER
THUNDERSTORMS ARE POSSIBLE ANYTIME AFTER ABOUT 5Z.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...JJ
SHORT TERM...ABE
LONG TERM...HAL
AVIATION...JJ
AREA FORECAST DISCUSSION...UPDATED
NWS PADUCAH KY
628 PM CDT Sat Jul 26 2014
.UPDATE...
Issued at 628 PM CDT SAT JUL 26 2014
Updated the aviation discussion for the 00Z TAF issuance.
&&
.SHORT TERM...(Tonight through Monday night)
Issued at 255 PM CDT SAT JUL 26 2014
All evidence points to the cap (see ILX and DVN 18Z RAOBS)
holding strong across the area late this afternoon and tonight.
The lone exception may be along the I-64 corridor, where a
complex of thunderstorms may push rapidly eastward generally in
the 01Z-05Z timeframe this evening.
The HRRR is still unable to generate a larger-scale bowing system,
as seen on some of the shorter range models this morning. The 12Z NAM
and GFS soundings show some weakness at times in the mid-level
flow across our north, so the overall organization of any storms
that develop may not be as significant as previously thought.
Individual storm cells may have enough 0-3KM SRH to support
rotating updrafts and would not be surprised to see some
supercells initially, where storms can develop this evening.
Damaging winds and large hail will be possible, and a few
tornadoes can not be ruled out with any individual cells this
evening. However, figure the cap will suppress any activity that
tries to dip south of I-64, or possibly even into our northern-
most counties.
The mid-upper 70 dewpoints have descended upon the region as expected,
and heat indices have reached triple digits over much of the area.
Already issued a Special Weather Statement for the heat. It should
subside by 7 PM, and would be surprised to see values above 105,
so will not be issuing a Heat Advisory at this time.
Overnight, the models struggle to generate much, if any,
convection over our region, so will keep PoPs at 30% or less.
The cold front will move through the region Sunday, and the low
to mid 70 dewpoints and temperatures well into the 90s are
expected ahead of it over the southeast 2/3 of the area in the
afternoon. This could lead to heat indices near today`s levels,
and a righteous airmass for strong to severe thunderstorms to feed
on. Winds ahead of the front will be nearly due west, and quite
strong, pushing Lake Wind Advisory levels, especially east of the
Mississippi River. The veered winds result in only weak
convergence along the boundary, so thunderstorm coverage is
expected to be widely scattered to scattered, with better coverage
later in the day along the Tennessee border. Certainly cannot rule
out a few severe storms mainly over west Kentucky and southwest
Indiana. The consensus of guidance is that most if not all of
the convective activity will shift south of the area by early
Sunday evening.
Will have a dry forecast for the entire area overnight Sunday
through Monday Night. A deep trough over the Great Lakes and
northeast will keep the area in strong northwest flow aloft
through the period. North winds will bring much cooler and drier
air into the region through the period, as well.
.LONG TERM...(Tuesday through Saturday)
Issued at 255 PM CDT SAT JUL 26 2014
Above medium confidence in the extended.
High pressure aloft will be firmly in place over west with a
persistent upper level trough over the east. This will place in a
much drier northerly flow in the fronts wake. This will also result
in unseasonable low RH reading for most of the upcoming week. By the
end of the week the upper level trough deepens and even suggest a
cut off upper low forming the lower Tennessee Valley Friday into the
weekend. This will allow for at least daytime storm chances mainly
in the afternoon with max heating...but could not rule out some
activity into the evening hours.
Temperatures will much cooler than normal through the extended with
lower to middle 80s for the region.
&&
.AVIATION...
Issued at 628 PM CDT SAT JUL 26 2014
Could see TSRA with MVFR cigs/vsbys at KEVV/KOWB between 02-05Z
with the passing of the Mesoscale Convective Complex. Would
normally expect TSRA with a FROPA on Sunday but models showing a
decent capping inversion so did not mention anything at this time.
South southwest winds AOB 10 knots overnight will pick up out of
the west at 12-14 knots gusting to 20-22 knots after 15Z, then
veer around to the northwest by the end of the period in the wake
of the FROPA.
&&
.PAH WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
MO...NONE.
IN...NONE.
KY...NONE.
&&
$$
SHORT TERM...DRS
LONG TERM...KH
AVIATION...JP
AREA FORECAST DISCUSSION
NWS BALTIMORE MD/WASHINGTON DC
914 PM EDT SAT JUL 26 2014
.SYNOPSIS...
A WARM FRONT WILL LIFT NORTH OF THE AREA EARLY SUNDAY. LOW PRESSURE
IS EXPECTED TO TRACK ACROSS PENNSYLVANIA SUNDAY NIGHT WITH AN
ASSOCIATED COLD FRONT MOVING ACROSS THE MID ATLANTIC. A REINFORCING
FRONT WILL CROSS THE REGION MONDAY. HIGH PRESSURE WILL BUILD IN
BEHIND THE FRONT BRINGING COOLER AND DRIER CONDITIONS DURING MIDWEEK.
&&
.NEAR TERM /THROUGH SUNDAY/...
WE WILL BE WATCHING MULTIPLE SHORTWAVES EMBEDDED WITHIN
WEST/NORTHWEST FLOW ALOFT OVER THE NEXT 24 OR SO HOURS.
CLOSEST UPSTREAM SHORTWAVE TO AFFECT THE CWA WAS MOVING INTO THE
POTOMAC HIGHLANDS AT 01Z. CONVECTION WAS STRONGER WHEN IT WAS OVER
OH/WV AND HAS WEAKENED SOME OVER THE PAST FEW HOURS. MODELS
INCLUDING HIGH RESOLUTION GUIDANCE HAVE NOT BEEN ABLE TO HANDLE
NEAR TERM CONVECTION VERY WELL THIS EVENING. MOST RECENT RUNS OF
THE HRRR HAVE LATCHED ONTO UPSTREAM CONVECTION BUT HRRR HAS
CONSISTENTLY BEEN DISSIPATING CONVECTION WHICH HASN/T HAPPENED
YET. ENVIRONMENT IS NOT SUPPORTIVE FOR SEVERE WX AS IT WAS IN OH
/AND THE SUN HAS NOW SET/...YET SHORTWAVE AND WARM ADVECTION WILL
LIKELY BE ABLE TO MAINTAIN SOME CONVECTION FOR AT LEAST A COUPLE
MORE HOURS INTO AT LEAST WESTERN MARYLAND...THE EASTERN WEST
VIRGINIA PANHANDLE AND INTO THE SHENANDOAH VALLEY OF VIRGINIA.
WHILE SEVERE WX IS NOT EXPECTED...HEAVY DOWNPOURS...LIGHTNING AND
LOCALLY GUSTY WINDS MAY OCCUR. WHETHER OR NOT CONVECTION LASTS
EAST OF THE BLUE RIDGE IS UNCERTAIN. CURRENT FORECAST LOWERS POPS
AT THIS POINT AND WILL NEED TO CONTINUE TO MONITOR RADAR TRENDS IN
CASE LATE EVENING POPS NEED TO BE INCREASED FURTHER DOWNSTREAM.
IN THE WAKE OF THE AFOREMENTIONED SHORTWAVE/EVENING
CONVECTION...ANOTHER SHORTWAVE OVER THE OHIO VALLEY MAY PROMOTE
LATE NIGHT AND EARLY SUNDAY MORNING CONVECTION AND POPS RAMP UP
/OR RE-RAMP UP/ FROM WEST TO EAST DURING THIS TIME. GIVEN TIME OF
DAY...SEVERE WX IS NOT EXPECTED WITH THIS ROUND EITHER HOWEVER
LOCALLY STRONG STORMS CAN/T BE RULED OUT.
A THIRD AND POSSIBLY STRONGEST SHORTWAVE /ALONG WITH MULTIPLE LOW
LEVEL BOUNDARIES/ THEN LOOKS TO PRODUCE MORE SHOWERS AND
THUNDERSTORMS SUNDAY AFTERNOON AND EVENING. CLOUDS FROM POTENTIAL
EARLY MORNING CONVECTION MAY HINDER INSTABILITY SLIGHTLY...BUT
EXPECTATION IS FOR ENOUGH OF A WINDOW FOR BREAKS IN THE CLOUDS TO
OCCUR TO CONTRIBUTE TO 1-2K J/KG CAPE COINCIDENT WITH 0-6KM SHEAR
LIKELY IN EXCESS OF 40 KT. POTENTIAL EXISTS FOR A WIDESPREAD
AND/OR SIGNIFICANT SEVERE EVENT SUNDAY AFTERNOON AND EVENING WITH
ALL SEVERE HAZARD TYPES POSSIBLE INCLUDING DAMAGING WINDS...LARGE
HAIL...FLASH FLOODING AND ALSO ISOLATED TORANDOES.
&&
.SHORT TERM /SUNDAY NIGHT THROUGH MONDAY/...
THUNDERSTORMS WILL CONTINUE INTO SUNDAY NIGHT AND EARLY MONDAY AS
THE COLD FRONT CROSSES THE MID-ATLANTIC. SHOWERS SHOULD BE OUT OF
THE REGION BY SUNRISE ON MONDAY AS THE LOW MOVES INTO NEW ENGLAND.
THE UPPER LEVEL TROUGH WILL BE MOVING OVER THE PA MONDAY AND COLD
AIR ADVECTION WILL LIKELY PRODUCE A CU FIELD ACROSS THE AREA.
SHOWERS AND ISO THUNDERSTORMS WITH GUSTY WINDS DUE TO AN INVERTED V
SIGNATURE WILL BE POSSIBLE.
&&
.LONG TERM /MONDAY NIGHT THROUGH SATURDAY/...
A LARGE AREA OF HIGH PRESSURE WILL BUILD SOUTH INTO THE AREA FROM
CANADA...RESULTING TO MUCH DRIER AND COOLER CONDITIONS FOR THE
MIDDLE PART OF THE WEEK. SUBSIDENCE WITH RIDGING ALOFT AND DRY AIR
IN THE LOW LEVELS SHOULD PRECLUDE ANY CONVECTION DURING THIS TIME.
TEMPERATURES WILL ALSO BE SEVERAL DEGREES BELOW NORMAL.
THE RIDGE OF HIGH PRESSURE WILL BEGIN TO PUSH OFFSHORE LATER IN THE
WEEK AS ANOTHER SLOW MOVING UPPER LEVEL TROUGH APPROACHES FROM THE
WEST...RESULTING IN AN INCREASE IN SHOWER AND THUNDERSTORM CHANCES
BY NEXT WEEKEND.
&&
.AVIATION /01Z SUNDAY THROUGH THURSDAY/...
MAIN CHALLENGE FOR THE TAFS REVOLVES AROUND POTENTIAL FOR CONVECTION
THROUGH SUNDAY EVENING. FIRST SHORTWAVE LIKELY BRINGS SHRA OR TSRA TO
MRB AND PERHAPS EVEN CHO IN THE 02Z-04Z WINDOW TONIGHT.
EXPECTATION IS FOR THUNDERSTORMS TO WEAKEN/DISSIPATE LATER THIS
EVENING AND NOT LAST MUCH FURTHER EAST. BUT HIGH RES GUIDANCE HAS
NOT HANDLED TRENDS WELL AND THIS PROVIDES UNCERTAINTY WITH THE
EASTWARD EXTENT.
ANOTHER SHORTWAVE BRINGS A CHANCE OF SHRA OR TSRA LATE TONIGHT
INTO EARLY SUNDAY MORNING...AND THEN A THIRD IS LIKELY TO PRODUCE
TSRA SUNDAY AFTERNOON AND EVENING. THIRD ROUND MAY BE THE
STRONGEST WITH HEAVY RAINFALL AND STRONG GUSTY WINDS.
A COLD FRONT WILL CROSS THE REGION LATE SUNDAY NIGHT INTO MONDAY
MORNING. WESTERLY WINDS WILL MOVE INTO THE REGION BEHIND THE FROPA
MONDAY. VFR MON NIGHT-WED W/ NW FLOW 10-20 KTS...GUSTY MON NIGHT
INTO TUE THEN DECREASING TO AROUND 10 KTS.
&&
.MARINE...
SOUTHERLY FLOW IS OCCURRING UP THE BAY AND IS EXPECTED TO CHANNEL
FOR LOW END SCA WINDS TONIGHT. THUNDERSTORMS ARE LIKELY
SUNDAY...PARTICULARLY AFTERNOON AND EVENING AND MAY CONTAIN LOW VIS
IN HEAVY RAIN AND ALSO STRONG WINDS /AND EVEN ISOLATED WATERSPOUTS/
WHICH WOULD REQUIRE SMW/S.
A COLD FRONT WILL CROSS THE WATERS MONDAY MORNING AND SCA WILL BE
LIKELY. SCA CONDITIONS POSSIBLE IN GUSTY NW FLOW ASSOCIATED WITH
PRESSURE SURGE BEHIND COLD FROPA MON EVE...SUBSIDING TUE THROUGH
THU.
&&
.TIDES/COASTAL FLOODING...
SOUTHERLY WIND CONTINUES TO SUPPORT POSITIVE TIDAL DEPARTURES. MAIN
CONCERN FOR THE NEXT HIGH TIDE CYCLE WILL BE AROUND ANNAPOLIS...WITH
A HIGH TIDE TIME OF 623 AM AT THE US NAVAL ACADEMY. ANOMALY THERE IS
AROUND 3/4 FT ABOVE. IF IT HOLDS THIS WOULD BRING WATER LEVELS ABOVE
THE MINOR FLOOD THRESHOLD. IT COULD EVEN GO UP A TAD WITH SOUTHERLY
FLOW. THEREFORE WILL ISSUE COASTAL FLOOD ADVISORY FOR ANNE ARUNDEL
FOR A 2.4-2.5 FT MLLW EXPECTED WATER LEVEL AT HIGH TIDE.
&&
.LWX WATCHES/WARNINGS/ADVISORIES...
DC...NONE.
MD...COASTAL FLOOD ADVISORY FROM 5 AM TO 9 AM EDT SUNDAY FOR MDZ014.
VA...NONE.
WV...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 6 AM EDT SUNDAY FOR ANZ531>534-537-
539>543.
&&
$$
SYNOPSIS...BPP/HAS
NEAR TERM...BPP/HAS
SHORT TERM...HAS
LONG TERM...DFH
AVIATION...BPP/HAS/DFH
MARINE...BPP/HAS/DFH
TIDES/COASTAL FLOODING...BPP
AREA FORECAST DISCUSSION
NWS PITTSBURGH PA
857 PM EDT SAT JUL 26 2014
.SYNOPSIS...
SHOWER AND THUNDERSTORM CHANCES...WITH THE RISK OF SEVERE WEATHER...WILL
INCREASE THROUGH SUNDAY. COLDER WEATHER CAN BE EXPECTED FOR NEXT WEEK.
&&
.NEAR TERM /UNTIL 6 AM SUNDAY MORNING/...
LINE OF THUNDERSTORMS WILL CONTINUE TO QUICKLY EXIT TO THE EAST IN
THE NEXT HOUR OR SO. HOWEVER...ANOTHER AREA OF STORMS COMING OFF
OF LAKE ERIE WILL LIKELY SUSTAIN THEMSELVES LONG ENOUGH TO MAKE IT
INTO THE REGION. THE HRRR MODEL SEEMS TO HANDLE THIS THE BEST AND
ALSO SUGGESTS THAT THE MCS OVER ILLINOIS AND INDIANA MAY CLIP OUR
SOUTHERN COUNTIES IN OHIO AND WV LATE TONIGHT/SUNDAY MORNING. WILL
MAINTAIN CHANCE POPS...INCREASING THEM TO LIKELY OVER THE
SOUTHERN HALF OF THE REGION THROUGH THE MORNING. CONSIDERING THAT
WE ARE QUICKLY LOSING DAYLIGHT....MOST OF THE INSTABILITY SHOULD
REMAIN ELEVATED...LIMITING ANY SEVERE THREAT FOR THE NIGHT.
&&
.SHORT TERM /6 AM SUNDAY MORNING THROUGH TUESDAY/...
THE PRIMARY CONCERN OF THE FORECAST EFFORT CONTS TO BE SUNDAY AS
DEEPENING SHRTWV IS PROJECTED ACRS THE GREAT LAKES AND TWD THE UPR
OH REGION. SEASONALLY STRONG JET STREAK WL INCRS THE MID AND UPR
WIND OVR BACKED SFC FLOW RESULTING IN SEVERE SPPRTG SPEED AND
DIRECTIONAL SHEAR. BNDRY POSITIONING AND INSTABILITY RMN THE
LIMITING FACTORS FOR THE UPR OH REGION GIVEN CLDS AND SHWR
DVLPMNT...BUT FALLING MID LVL TEMPS WITH THE ADVN OF THE MID LVL
THERMAL TROF ARE EXPECTED OFFSET...ESPECIALLY LTR IN THE DAY.
THE BOTTOM LINE IS THAT THE ENTIRE AREA HAS BEEN HIGHLIGHTED FOR A
FULL ARRAY SEVERE RISK...BETTER CHC FOR WHICH IS PROJECTED
OVR...AND IN VCNTY OF EAST CENTRAL OHIO AND NORTHERN WEST
VIRGINIA. THE STORM PREDICTION CENTER HAS BLANKETED THAT AREA WITH
A MODERATE SEVERE RISK.
PASSAGE OF THIS SYSTEMS CDFNT ON SUNDAY NGT WL END THE SVR THREAT
AND BGN THE DOWNWARD TEMP TREND. MORE SHWRS ARE LIKELY ON MONDAY
AS A HIGH AMPLITUDE UPR TROF DVLPS OVR THE ERN CONUS...WITH
REINFORCING SFC FRONT SLATED FOR A MIDDAY PASSAGE ACRS THE UPR OH REGION.
&&
.LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/...
HIGH PRESSURE UNDER UPPER LEVEL TROUGHING WILL PROVIDE A COOL AND
COMFORTABLE MIDWEEK. ANOTHER WEAK COLD FRONT MAY BRING SHOWERS
THURSDAY.
&&
.AVIATION /00Z SUNDAY THROUGH THURSDAY/...
SEVERAL SHORTWAVES WILL CONTINUE THE CHANCE FOR SHOWERS AND
THUNDERSTORMS AND OCCASIONAL RESTRICTIONS THROUGH MUCH OF THE
TAF PERIOD. WENT WITH A GENERAL VCSH MENTION AND TRIED TO TEMPO
SHOWERS/STORMS AS NEEDED OVERNIGHT AS STORMS MOVING SOUTH FROM
LAKE ERIE AND THE MCS OVER IN/IL APPROACH. LOOKING AT DOWNSTREAM
OBS OVER WESTERN OHIO...MANY TAF SITES MAY EXPERIENCE MVFR CIGS
FOR A PERIOD OVERNIGHT. OPTED TO MENTION THIS ACROSS THE BOARD BUT
CONFIDENCE WAS NOT GREAT ENOUGH TO MAKE IT PREVAILING EVERYWHERE.
WHILE CONDITIONS MAY RETURN TO VFR EVERYWHERE TOMORROW
MORNING...ADDITIONAL STRONG TO SEVERE STORMS WILL BE POSSIBLE IN
THE AFTERNOON AS LOW PRESSURE APPROACHES. WILL MAINTAIN THE VCTS
MENTION FOR NOW CONSIDERING THE LOW CONFIDENCE IN EXACT TIMING BUT
EXPECT VSBY RESTRICTIONS WILL OCCUR AT ANY SITE THAT ENCOUNTERS A
T-STORM.
OUTLOOK.../SUNDAY NIGHT THROUGH THURSDAY/...
RSTRNS ARE LIKELY THRU MON AS A CDFNT CROSSES THE RGN.
&&
.PBZ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
OH...NONE.
PA...NONE.
WV...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
409 PM EDT FRI JUL 25 2014
.SHORT TERM...(THIS EVENING THROUGH SATURDAY)
ISSUED AT 343 PM EDT FRI JUL 25 2014
12Z RAOBS/LATEST WV IMAGERY AND RUC ANALYSIS SHOW A WNW FLOW ALF
OVER THE UPR LKS BTWN DEEP CLOSED LO OVER NRN QUEBEC AND SHRTWV RDG
AXIS EXTENDING NNEWD INTO MN/NW ONTARIO FM CENTER OF HIER HGTS OVER
THE SRN ROCKIES. ALTHOUGH SLOW INFLUX OF MOISTER AIR IN THE GENERAL
SW FLOW BTWN SFC/H85 HI OVER THE MID ATLANTIC STATES AND LOWER MSLP
IN THE NRN PLAINS ASSOCIATED WITH A DEEP CLOSED LO IN SRN
SASKATCHEWAN THAT IS RIDING OVER THE RDG CENTERED IN THE SRN ROCKIES
HAS ALLOWED FOR A GOOD DEAL OF CLDS/A FEW SHOWERS OVER MAINLY THE W
HALF OF THE CWA TDAY...MAIN FOCUS FOR HEAVIER PCPN HAS BEEN WELL TO
THE SW CLOSER TO SHARP H85 WARM FNT STRETCHING FM THE DAKOTAS INTO
THE MID MS RIVER VALLEY. HI STABILITY SHOWN ON THE 12Z INL RAOB AND
ESPECIALLY THE GRB RAOB...WHICH DEPICTS A SHARP INVRN ARND H75...HAS
TENDED TO LIMIT THE INTENSITY AND COVERAGE OF THE SHOWERS THAT HAVE
IMPACTED UPR MI. OVER THE ERN CWA...VERY DRY/STABLE AIRMASS SHOWN ON
THE 12Z APX RAOB HAS ALLOWED FOR MORE SUNSHINE. BUT TO THE W...MORE
SHOWERS ARE PRESENT IN NE MN/WRN LK SUP IN AREA OF HIER H85 THETA E
ADVCTN IN ADVANCE OF A WEAK SHRTWV MOVING E ALONG THE CNDN BORDER
ARND CLOSED LO IN SASKATCHEWAN. BUT EWD PUSH OF DRIER AIR IN THE NRN
PLAINS IS TENDING TO LIMIT THE OVERALL COVERAGE OF THESE SHOWERS AS
WELL.
MAIN FCST CONCERNS IN THE SHORT TERM INVOLVE PCPN CHCS ASSOCIATED
WITH SHRTWV NOW MOVING ALONG THE CNDN BORDER.
LATE TDAY/TNGT...EXPECT AREA OF SHOWERS NOW IN NE MN AND A FEW
TS...THE POTENTIAL OF WHICH WL BE LIMITED BY PERSISTENT HIER MID LVL
STABILITY DEPICTED BEST ON THE GFS FCST SDNGS...TO SPREAD W-E INTO
UPR MI WITH AREA OF POSITIVE H85 THETA E ADVCTN THAT WL LIFT PWAT UP
TO ARND 1.5 INCHES/AXIS OF SOME H85-5 QVECTOR CNVGC IN ADVANCE OF
SHRTWV NOW TRACKING E ALONG THE CNDN BORDER. BUT ARRIVAL OF DRY AIR
NOW IN THE NRN PLAINS WL TEND TO DIMINISH THE POPS LATER EVEN THOUGH
THERE ARE HINTS A 2ND SHRTWV MIGHT FOLLOW INTO THE UPR LKS. FCST
LARGE SCALE QVECTOR DVGC OVER THE W LATE INDICATES THE DRYING WL
OVERCOME ANY PVA ASSOCIATED WITH THIS TRAILING SHRTWV. GOING FCST
POPS ARE IN PRETTY GOOD SHAPE AND NEED ONLY SMALL ADJUSTMENTS.
DESPITE THE MID LVL DRYING LATE...DVLPG LO CLDS WL LIMIT THE DIURNAL
TEMP FALL.
SAT...ANY LINGERING MRNG SHOWERS OVER MAINLY THE NE CWA WL END WITH
ARRIVAL OF DRIER AIR ALF THAT WL DEPRESS PWAT TO 0.75-1.0 INCH/DNVA
AND DEEP LYR QVECTOR DVGC AHEAD OF SHRTWV RDG TRAILING THE DEPARTING
2ND SHRTWV. WITH MRNG LO CLDS GIVING WAY TO MORE SUNSHINE AND FCST
H85 TEMPS AS HI AS 17-18C OVER THE W BY 00Z SUN...EXPECT MAX TEMPS
TO RISE INTO THE 80S AWAY FM THE MODERATING INFLUENCE OF THE GREAT
LKS. GIVEN THE MID LVL DRYING/POTENTIAL FOR DEEP MIXING AND NEAR
ADIABATIC LLVL LAPSE RATES...PREFER THE HIER END OF GUIDANCE FOR MAX
TEMPS...AT LEAST OVER THE INTERIOR W HALF. SOME OF THE HIER RES
MODELS...MAINLY THE 12Z NAM AND REGIONAL CNDN MODEL...DO INDICATE
THIS DAYTIME HEATING WL TRIGGER SOME SHOWERS/TS OVER THE ERN CWA IN
THE AFTN WITH CONVERGING LK BREEZES OFF LKS SUP/MI UNDER SOMEHWAT
LOWER HGTS. THE MAIN LIMITING FACTOR FOR THE DLPMNT OF THESE LK
BREEZE SHOWERS/TS WL BE THE DRYING ALF THAT IS FCST TO MIX TO THE
SFC WITH THE DAYTIME HEATING. IN FACT...DEEP MIXING ON THE GFS/NAM
FCST SDNGS HINT SFC DEWPTS OVER THE INTERIOR W HALF COULD MIX OUT AS
LO AS 45-50 LATE IN THE DAY...WITH KINX DROPPING TO 15-20. THE NAM
FCST SDNG FOR NEWBERRY AT 18Z SHOWS SBCAPE ARND 2K G/KG FOR SFC T/TD
OF 75/65. PREFER THE MORE CONSERVATIVE GFS FCST FOR SFC T/TD OF
75/60 AND SBCAPE CLOSE TO 700 J/KG. DESPITE THE LIMITATION OF THE
LARGE SCALE DRYING...WL MAINTAIN SOME LO CHC POPS OVER THE ERN CWA
TO ACCOUNT FOR THE LK BREEZE CNVGC.
.LONG TERM...(SATURDAY NIGHT THROUGH FRIDAY)
ISSUED AT 407 PM EDT FRI JUL 25 2014
COOL SUMMER PATTERN PERSISTS AS LARGE SCALE TROUGHING IS FORECAST TO
CONTINUE THROUGH DAYS 7-10. TEMPERATURES REMAIN BELOW NORMAL WITH
THE COOLEST DAYS EXPECTED MONDAY AND TUESDAY AS CORE OF UPPER LOW
AND COLD AIR MOVES ACROSS GREAT LAKES. MAX TEMPS BOTH DAYS LIKELY
WILL END UP AT LEAST 10 DEGREES BELOW NORMAL. NORMAL HIGHS THIS TIME
OF YEAR ARE IN THE MID 70S TO LOW 80S. MIN TEMPS WILL BE 5 TO 10
DEGREES BELOW NORMAL. NORMAL MIN TEMPS ARE IN THE LOW TO MID 50S.
OVERALL THIS PATTERN LOOKS DRY THROUGH THE NEXT COUPLE WEEKS PER THE
MEDIUM RANGE MODELS AND LATEST CPC OUTLOOKS.
BEST SHOT OF RAIN IS LATER SATURDAY NIGHT THROUGH SUNDAY AS UPPER
LOW AND STRONGER SHORTWAVE CURRENTLY OVER SOUTHERN SASKATCHEWAN
MOVES ACROSS WITH ASSOCIATED DEEP LAYER Q-VECTOR CONVERGENCE.
PASSAGE OF SHORTWAVE OCCURS AS THE INITIAL STRONG SFC-H85 COLD FRONT
IS CROSSING THE UPPER GREAT LAKES. MAIN ISSUE IS HOW FAST WILL THE
RAIN ARRIVE SATURDAY NIGHT AND ALSO IF THERE IS ANY POTENTIAL FOR
TSRA. SI/S BARELY BUMP BLO ZERO AND THAT IS FOCUSED ALONG THE WI
BORDER. HIGHEST POPS EXPECTED JUST TO NORTH OF UPPER LOW/SHORTWAVE
TRACK...MAINLY 09Z-21Z SUNDAY. TSRA CHANCES ARE THERE...BUT ARE
LIMITED TO A CHANCE AT BEST. UNLESS THE STORMS FORM EARLIER SATURDAY
EVENING WHEN DEEP SHEAR IS 30-40 KTS AND MLCAPE IS OVER 1000 J/KG...
DO NOT EXPECT ANY SEVERE STORMS SATURDAY NIGHT. INTO SUNDAY IT IS
POSSIBLE THAT IF THE SYSTEM SLOWS THERE WOULD BE INCREASED POTENTIAL
FOR SFC BASED TSRA SUNDAY AFTN. ATTM THOUGH LI/S BLO ZERO ARE
FORECAST TO STAY OVER WI AS STABLE COOL RAINY NORTH FLOW SHUNTS THE
GREATER INSTABILITY TO THE SOUTH. LOWERED TEMPS MORE ALONG LK
SUPERIOR ON SUNDAY...WITH UPR 50S TO AROUND 60 DEGREES. POINTS
FARTHER INLAND OVER SOUTHERN U.P. MAY BE ABLE TO REACH 70 DEGREES AT
LEAST BRIEFLY BEFORE CLOUDS THICKEN AND WIDESPREAD SHOWERS BEGIN.
SHOULD NOTE THAT THE STRONGER NORTH WINDS AND HIGHER WAVES WILL
INCREASE SWIM RISK FOR BEACHES OF LK SUPERIOR MQT TO GRAND MARAIS
SUNDAY INTO MONDAY. IF THE AIR TEMPS REMAIN IN THE UPPER 50S OR
HIGHER...WOULD NEED A BEACH HAZARD STATEMENT TO HIGHLIGHT THE RISK
EITHER FOR SUNDAY OR MONDAY OR POSSIBLY BOTH DAYS. ULTIMATELY WILL
DEPEND ON THE EXPECTED WEATHER FOR THE DAY.
BEYOND SUNDAY...UPPER TROUGH IN THE VCNTY COUPLED WITH INDIVIDUAL
SHORTWAVES AND AREAS OF DEEPER MOISTURE DROPPING ACROSS THE AREA
WILL COMBINE WITH DAYTIME HEATING/INSOLATION TO PRODUCE ISOLD-SCTD
SHOWERS...MAINLY DURING AFTN AND EVENING HOURS OF TUESDAY AND
WEDNESDAY. GRADUAL RISING HEIGHTS RESULT IN LESS CYCLONIC LOW-LEVEL
FLOW BY THURSDAY AND THERE IS ALSO LESS DEEP MOISTURE BY THAT POINT.
EXPECT THE CHANCES OF DIURNAL SHOWERS TO DIMINISH BY LATE THIS WEEK
AS TEMPS BEGIN TO WARM UP AGAIN. JUST ENOUGH MLCAPE DURING THE AFTN
FAR INLAND TO PUT KEEP SMALL TSRA CHANCES AS WELL WITH THE SHRA. MEAN
WINDS FM NORTH TO SOUTH RESULT IN GREATEST CHANCES FOR RAIN MOST DAYS
FARTHEST INLAND FROM THE MODERATION/STABILIZING INFLUENCE OF LK
SUPERIOR.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON)
ISSUED AT 129 PM EDT FRI JUL 25 2014
WITH INFLUX OF MOISTER AIR IN LLVL SW FLOW AND APRCH OF AN UPPER
DISTURBANCE...EXPECT SHRA AND AREA OF MVFR CLDS NEAR IWD TO
OVERSPREAD CMX AND SAW BY THIS EVNG. WITH SOME DRYING ALF LATE TNGT
THAT WL END THE SHOWERS...EXPECT IFR CONDITIONS TO DVLP IN THE
PRESENCE OF DIURNAL COOLING. LIFR CONDITIONS ARE NOT OUT OF THE
QUESTION. THE ARRIVAL OF DRIER AIR AND DAYTIME WL RESULT IN
IMPROVEMENT TO VFR ON SAT. THIS PROCESS WL BE SLOWEST AT CMX WITH AN
UPSLOPE W WIND.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 407 PM EDT FRI JUL 25 2014
EXPECT WINDS UNDER 15 KTS THRU SAT NIGHT WITH RELATIVELY WEAK PRES
GRADIENT DOMINATING THE UPPER LAKES. STRONGER N WINDS UP TO 20-25
KTS EXPECTED SUN INTO MON AS COOLER AIR INVADES THE AREA UNDER
TIGHTER GRADIENT BETWEEN HI PRES MOVING INTO THE NORTHERN PLAINS AND
LO PRES OVER THE SE GREAT LAKES. WINDS WILL DIMINISH ON TUE AND BACK
TOWARD THE W WITH CLOSER APPROACH OF HI PRES FROM THE PLAINS.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...KC
LONG TERM...JLA
AVIATION...KC
MARINE...TITUS/JLA
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
344 PM EDT FRI JUL 25 2014
.SHORT TERM...(THIS EVENING THROUGH SATURDAY)
ISSUED AT 343 PM EDT FRI JUL 25 2014
12Z RAOBS/LATEST WV IMAGERY AND RUC ANALYSIS SHOW A WNW FLOW ALF
OVER THE UPR LKS BTWN DEEP CLOSED LO OVER NRN QUEBEC AND SHRTWV RDG
AXIS EXTENDING NNEWD INTO MN/NW ONTARIO FM CENTER OF HIER HGTS OVER
THE SRN ROCKIES. ALTHOUGH SLOW INFLUX OF MOISTER AIR IN THE GENERAL
SW FLOW BTWN SFC/H85 HI OVER THE MID ATLANTIC STATES AND LOWER MSLP
IN THE NRN PLAINS ASSOCIATED WITH A DEEP CLOSED LO IN SRN
SASKATCHEWAN THAT IS RIDING OVER THE RDG CENTERED IN THE SRN ROCKIES
HAS ALLOWED FOR A GOOD DEAL OF CLDS/A FEW SHOWERS OVER MAINLY THE W
HALF OF THE CWA TDAY...MAIN FOCUS FOR HEAVIER PCPN HAS BEEN WELL TO
THE SW CLOSER TO SHARP H85 WARM FNT STRETCHING FM THE DAKOTAS INTO
THE MID MS RIVER VALLEY. HI STABILITY SHOWN ON THE 12Z INL RAOB AND
ESPECIALLY THE GRB RAOB...WHICH DEPICTS A SHARP INVRN ARND H75...HAS
TENDED TO LIMIT THE INTENSITY AND COVERAGE OF THE SHOWERS THAT HAVE
IMPACTED UPR MI. OVER THE ERN CWA...VERY DRY/STABLE AIRMASS SHOWN ON
THE 12Z APX RAOB HAS ALLOWED FOR MORE SUNSHINE. BUT TO THE W...MORE
SHOWERS ARE PRESENT IN NE MN/WRN LK SUP IN AREA OF HIER H85 THETA E
ADVCTN IN ADVANCE OF A WEAK SHRTWV MOVING E ALONG THE CNDN BORDER
ARND CLOSED LO IN SASKATCHEWAN. BUT EWD PUSH OF DRIER AIR IN THE NRN
PLAINS IS TENDING TO LIMIT THE OVERALL COVERAGE OF THESE SHOWERS AS
WELL.
MAIN FCST CONCERNS IN THE SHORT TERM INVOLVE PCPN CHCS ASSOCIATED
WITH SHRTWV NOW MOVING ALONG THE CNDN BORDER.
LATE TDAY/TNGT...EXPECT AREA OF SHOWERS NOW IN NE MN AND A FEW
TS...THE POTENTIAL OF WHICH WL BE LIMITED BY PERSISTENT HIER MID LVL
STABILITY DEPICTED BEST ON THE GFS FCST SDNGS...TO SPREAD W-E INTO
UPR MI WITH AREA OF POSITIVE H85 THETA E ADVCTN THAT WL LIFT PWAT UP
TO ARND 1.5 INCHES/AXIS OF SOME H85-5 QVECTOR CNVGC IN ADVANCE OF
SHRTWV NOW TRACKING E ALONG THE CNDN BORDER. BUT ARRIVAL OF DRY AIR
NOW IN THE NRN PLAINS WL TEND TO DIMINISH THE POPS LATER EVEN THOUGH
THERE ARE HINTS A 2ND SHRTWV MIGHT FOLLOW INTO THE UPR LKS. FCST
LARGE SCALE QVECTOR DVGC OVER THE W LATE INDICATES THE DRYING WL
OVERCOME ANY PVA ASSOCIATED WITH THIS TRAILING SHRTWV. GOING FCST
POPS ARE IN PRETTY GOOD SHAPE AND NEED ONLY SMALL ADJUSTMENTS.
DESPITE THE MID LVL DRYING LATE...DVLPG LO CLDS WL LIMIT THE DIURNAL
TEMP FALL.
SAT...ANY LINGERING MRNG SHOWERS OVER MAINLY THE NE CWA WL END WITH
ARRIVAL OF DRIER AIR ALF THAT WL DEPRESS PWAT TO 0.75-1.0 INCH/DNVA
AND DEEP LYR QVECTOR DVGC AHEAD OF SHRTWV RDG TRAILING THE DEPARTING
2ND SHRTWV. WITH MRNG LO CLDS GIVING WAY TO MORE SUNSHINE AND FCST
H85 TEMPS AS HI AS 17-18C OVER THE W BY 00Z SUN...EXPECT MAX TEMPS
TO RISE INTO THE 80S AWAY FM THE MODERATING INFLUENCE OF THE GREAT
LKS. GIVEN THE MID LVL DRYING/POTENTIAL FOR DEEP MIXING AND NEAR
ADIABATIC LLVL LAPSE RATES...PREFER THE HIER END OF GUIDANCE FOR MAX
TEMPS...AT LEAST OVER THE INTERIOR W HALF. SOME OF THE HIER RES
MODELS...MAINLY THE 12Z NAM AND REGIONAL CNDN MODEL...DO INDICATE
THIS DAYTIME HEATING WL TRIGGER SOME SHOWERS/TS OVER THE ERN CWA IN
THE AFTN WITH CONVERGING LK BREEZES OFF LKS SUP/MI UNDER SOMEHWAT
LOWER HGTS. THE MAIN LIMITING FACTOR FOR THE DLPMNT OF THESE LK
BREEZE SHOWERS/TS WL BE THE DRYING ALF THAT IS FCST TO MIX TO THE
SFC WITH THE DAYTIME HEATING. IN FACT...DEEP MIXING ON THE GFS/NAM
FCST SDNGS HINT SFC DEWPTS OVER THE INTERIOR W HALF COULD MIX OUT AS
LO AS 45-50 LATE IN THE DAY...WITH KINX DROPPING TO 15-20. THE NAM
FCST SDNG FOR NEWBERRY AT 18Z SHOWS SBCAPE ARND 2K G/KG FOR SFC T/TD
OF 75/65. PREFER THE MORE CONSERVATIVE GFS FCST FOR SFC T/TD OF
75/60 AND SBCAPE CLOSE TO 700 J/KG. DESPITE THE LIMITATION OF THE
LARGE SCALE DRYING...WL MAINTAIN SOME LO CHC POPS OVER THE ERN CWA
TO ACCOUNT FOR THE LK BREEZE CNVGC.
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 451 AM EDT FRI JUL 25 2014
A SOMEWHAT ACTIVE WEATHER PATTERN WILL BE IN PLACE ACROSS THE REGION
THROUGH THE WEEKEND...WITH A SIGNIFICANT COOLDOWN STARTING SUNDAY
AND EXTENDING INTO NEXT WEEK.
ON SATURDAY...THE FORECAST AREA WILL REMAIN UNDER ZONAL W-NW FLOW
ALOFT WITH THE LEFT EXIT REGION OF THE JET AND ASSOCIATED SHORT
WAVE EXITING TO THE EAST. ANY REMAINING SHOWER ACTIVITY FROM FRI
NIGHT SHOULD EXIT AS WELL AS DRY ADVECTION MOVES ACROSS THE AREA.
THIS WILL ALLOW FOR CLEARING SKIES WITH TEMPERATURES TO WARM INTO
THE MID-UPPER 70S ACROSS THE AREA. ALL THE NUMERICAL GUIDANCE
SUGGEST THAT INSTABILITY WILL INCREASE ACROSS THE EASTERN HALF OF
THE FORECAST AREA DURING THE AFTERNOON IN RESPONSE TO THE DIURNAL
HEATING. ALTHOUGH THE FORECAST CAPE VALUES OF 1000-2000 J/KG IS
LIKELY TOO HIGH DUE TO THE NORMAL HIGH BIAS OF SFC DEW
POINTS...THERE WILL LIKELY STILL BE INSTABILITY OF AT LEAST 1000
J/KG DURING THE LATE MORNING/AFTERNOON SIMPLY DUE TO THE STEEPER
LAPSE RATES ALOFT OF 6.5 C/KM. AS SUCH...HAVE OPTED TO MAINTAIN
CHANCE POPS ACROSS THE EASTERN LAKE BREEZE AREAS DURING THE
AFTERNOON HOURS ESPECIALLY WITH THE NAM AND GFS KEEPING THE LEFT
EXIT REGION OF THE JET AND ASSOCIATED WEAK Q-VECTOR CONVERGENCE IN
THIS AREA DURING THE AFTERNOON. THE BIG LIMITING FACTOR FOR MORE
WIDESPREAD CONVECTION WILL BE THE DRY AIR ALOFT...AND LACK OF
SIGNIFICANT LOW LEVEL FORCING OTHER THAN THE LAKE BREEZE ACTIVITY.
THIS AGREES WELL WITH THE HIGH RES NUMERICAL GUIDANCE THAT SUGGEST A
FEW STORMS ALONG THE LAKE BREEZE DURING THE DAY.
ON SATURDAY NIGHT INTO SUNDAY...THE UPPER LOW CURRENTLY OVER ALBERTA
WILL MOVE TOWARD THE AREA. MEANWHILE...THE UPPER LOW NE OF JAMES BAY
WILL RETROGRADE SLIGHTLY TO THE WEST AND SOUTH. THESE TWO FEATURES
WILL ALLOW FOR THE FRONT TO THE NORTH OF THE AREA TO MOVE ACROSS THE
REGION LATE SAT NIGHT INTO SUNDAY MORNING. AS THIS OCCURS...LOW
PRESSURE ASSOCIATED WITH THE UPPER LOW TO THE WEST WILL MOVE ALONG
THE FRONT ON SAT NIGHT INTO SUNDAY...TRACKING SOUTH OF THE AREA.
SHOWER AND ISOLATED STORMS WILL MOVE INTO THE AREA LATER SAT NIGHT
AHEAD OF THE UPPER LOW...THEN SPREAD ACROSS THE ENTIRE FORECAST AREA
ON SUNDAY. SUNDAY SHOULD END UP BEING A FAIRLY COOL AND DAMP DAY
WITH A BRISK /AT LEAST FOR SUMMER/ NORTH WIND. TEMPERATURES WILL
REMAIN FAIRLY STEADY IN THE 60S ACROSS THE AREA. IN FACT...IT WOULD
NOT BE SURPRISING IF TEMPS WILL FALL DURING THE DAY ESPECIALLY
CLOSER TO LAKE SUPERIOR AS 850MB TEMPS DROP TO 10C BY SUN EVENING.
THE GOOD NEWS IS THAT THE RAIN SHOULD RAPIDLY END LATE SUN AFTERNOON
INTO SUNDAY EVENING AS THE LOW MOVES EAST OF THE AREA. HOWEVER...BY
MONDAY MORNING 850MB TEMPS WILL DROP TO +6C WHICH WILL ALLOW FOR A
COOL NIGHT SUNDAY NIGHT. MONDAY WILL BE TRANQUIL AS WELL WITH STABLE
NORTH WINDS AND BUILDING HIGH PRESSURE ACROSS THE UPPER GREAT LAKES.
FOR THE TUE-THU TIME PERIOD...THE UPPER GREAT LAKES WILL REMAIN
BELOW NORMAL WITH THE DEEP TROUGH PERSISTING ACROSS THE EASTERN HALF
OF THE U.S. THROUGH THE PERIOD. THE UPPER LOW JUST EAST OF HUDSON
BAY WILL REMAIN FAIRLY STATIONARY THROUGH THE PERIOD. WEAK UPPER
LEVEL SHORT WAVES WILL ROTATE AROUND THE UPPER LOW AND ACROSS THE
AREA...WHICH WILL MAKE TIMING OF PRECIPITATION SOMEWHAT DIFFICULT.
HOWEVER...WITH THE COLD TEMPERATURES ALOFT COMBINED WITH FAIRLY
FREQUENT DISTURBANCES ALOFT...EXPECT THE BEST CHANCES FOR SHOWERS
AND STORMS TO BE DURING THE PEAK HEATING HOURS IN THE AFTERNOON AND
EARLY EVENING HOURS EACH DAY. OTHERWISE...TEMPERATURES WILL REMAIN
BELOW NORMAL THROUGH THE PERIOD.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON)
ISSUED AT 129 PM EDT FRI JUL 25 2014
WITH INFLUX OF MOISTER AIR IN LLVL SW FLOW AND APRCH OF AN UPPER
DISTURBANCE...EXPECT SHRA AND AREA OF MVFR CLDS NEAR IWD TO
OVERSPREAD CMX AND SAW BY THIS EVNG. WITH SOME DRYING ALF LATE TNGT
THAT WL END THE SHOWERS...EXPECT IFR CONDITIONS TO DVLP IN THE
PRESENCE OF DIURNAL COOLING. LIFR CONDITIONS ARE NOT OUT OF THE
QUESTION. THE ARRIVAL OF DRIER AIR AND DAYTIME WL RESULT IN
IMPROVEMENT TO VFR ON SAT. THIS PROCESS WL BE SLOWEST AT CMX WITH AN
UPSLOPE W WIND.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 427 AM EDT FRI JUL 25 2014
EXPECT WINDS UNDER 15 KTS THRU SAT NIGHT WITH RELATIVELY WEAK PRES
GRADIENT DOMINATING THE UPPER LAKES. STRONGER N WINDS UP TO 20-25
KTS ARE POSSIBLE ON SUN INTO MON AS COOLER AIR INVADES THE AREA
UNDER TIGHTER GRADIENT BETWEEN HI PRES MOVING INTO THE NORTHERN
PLAINS AND LO PRES OVER THE SE GREAT LAKES. WINDS WILL DIMINISH ON
TUE AND BACK TOWARD THE W WITH CLOSER APPROACH OF HI PRES FROM THE
PLAINS.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...KC
LONG TERM...MRD
AVIATION...KC
MARINE...TITUS
AREA FORECAST DISCUSSION
NWS GAYLORD MI
227 PM EDT FRI JUL 25 2014
.SYNOPSIS...
ISSUED AT 303 AM EDT FRI JUL 25 2014
HIGH PRESSURE WILL GIVE WAY TO A FAST MOVING SYSTEM TONIGHT AND
SATURDAY. CLOUDS WILL BE ON THE INCREASE TODAY...WITH A CHANCE FOR
SHOWERS AND A FEW THUNDERSTORMS TONIGHT INTO THE START OF THE
WEEKEND. A MUCH STRONGER SYSTEM WILL ARRIVE TO END THE WEEKEND...
BRINGING BETTER POTENTIAL FOR SHOWERS SUNDAY AND SUNDAY NIGHT. A
RETURN TO MUCH BELOW NORMAL TEMPERATURES ON MONDAY...WITH ONLY A
SLOW MODERATION EXPECTED THROUGH THE REMAINDER OF THE WEEK.
&&
.UPDATE...
ISSUED AT 201 PM EDT FRI JUL 25 2014
INSERTED SOME ISOLATED POPS IN THE SW COUNTIES AS THE SOME
MOISTURE RIDES DOWN THE FORMING WARM FRONT AND IS GENERATING SOME
SHOWERS. HOWEVER, THEY ARE HAVING A HARD TIME GETTING INTO THE
FORECAST AREA, MUCH WITH THE DRY AIR IT WILL TAKE UNTIL THIS
EVENING BEFORE THAT HAPPENS.
UPDATE ISSUED AT 948 AM EDT FRI JUL 25 2014
RAIN SHOWERS OVER WISCONSIN ARE TRYING TO MAKE THEIR WAY INTO N
LOWER FOR THE AFTERNOON. WILL BE WATCHING THESE AS THEY SEEMED TO
BE HIGH BASED SHOWERS (9000-10000FT BASES) WITH SCT DECKS DOWN
LOWER. KAPX 12Z SOUNDING SHOWED LOTS OF DRY AIR, BUT ACROSS THE
LAKE KGRB 12Z SOUNDING SHOWED SOME MOISTENING BETWEEN 925 MB AND
750 MB. HOWEVER, BOTH SOUNDINGS SHOWED PRONOUNCED CAPPING
INVERSION AROUND 750 MB. SO WE ARE IN A WAIT AND SEE GAME, GUT
FEELING IS THAT WE SEE SOME SPRINKLES IN THE AFTERNOON, BUT NO
MEASURABLE RAIN SHOWERS. MAY HAVE TO BUMP THE POPS UP TO ISOLATED
SHOWERS IN NW LOWER DEPENDING ON THE TRENDS.
&&
.SHORT TERM...(TODAY THROUGH TONIGHT)
ISSUED AT 303 AM EDT FRI JUL 25 2014
...MORE CLOUDS AND A SHADE WARMER WITH STORM CHANCES TONIGHT...
IMPACTS: LIGHTNING...BUT NO SEVERE WEATHER EXPECTED.
CURRENT WEATHER AND SYNOPTIC PATTERN:
BROAD UPPER RIDGING SEEN OVER THE SW PART OF THE COUNTRY WHILE
TROUGHING IS STILL THE THEME OVER THE EASTERN CONUS. THE RIDGING HAS
BEEN SQUASHED DUE TO A WRAPPED UP CLOSED LOW DRIFTS ACROSS SW
CANADA. THIS HAS INDUCED LOW PRESSURE OVER EASTERN CANADA AND THE
NRN PLAINS. AN AXIS OF DEEP THETA-E AIR...LEADING EDGE OF STEEP
LAPSE RATES ALOFT (6.5C/KM-7.5C/KM) AND LLJ (45-55KT) CONVERGENCE
AHEAD OF THE PLAINS SFC LOW HAS RESULTED IN POCKETS OF SHOWERS AND
STORMS IN THE DAKOTAS DOWN TO NE. CLOSER TO HOME...AREA VAD WIND
PROFILES AND RUC ANALYSIS SHOWING A TROUGH AXIS AND H8 MOISTURE
ADVECTION FROM THE ARROWHEAD OF MN DOWN THROUGH WISCONSIN. THERE
WERE A FEW ELEVATED RETURNS...BUT ONLY A FEW SPRINKLES HITTING
GROUND PER AREA OBS. OVER NRN MICHIGAN...WE ARE STILL UNDER THE
INFLUENCE OF SFC HIGH PRESSURE...BUT THOSE SAME VAD WIND PROFILES
SHOW THAT THIS HAS SHIFTED JUST EAST OF US WITH A RETURN TO A SW
WIND. AIR MASS IS STILL QUITE DRY WITH PWATS RELATIVELY LOWER THAN
ANYWHERE NEARBY. ONLY A BAND OF HIGHER LEVEL CLOUD STREAMING DOWN
THROUGH THE NW FLOW ALOFT. THE DRY AIR AND MOSTLY CLEAR SKIES HAVE
ALLOWED TEMPERATURES TO FALL INTO THE LOWER HALF OF THE 40S IN THE
LOW LYING AREAS...WHILE COASTAL AREAS AND SOME EXPOSED HIGHER
TERRAIN ARE IN THE LOWER HALF OF THE 50S.
SYNOPTIC PATTERN/WEATHER EVOLUTION:
THE SFC HIGH GRADUALLY SINKS OFF TO THE SE TODAY...WHILE THE
SOUTHERLY PRESSURE GRADIENT TIGHTENS AND DRAWS IN MORE LOW LEVEL
MOISTURE THROUGH THE DAY AND NIGHT. THE INITIAL H8 TROUGH AND
MOISTURE ADVECTION WILL DRIFT OVERHEAD TODAY...AND MAYBE SOME
SPRINKLES ARE POSSIBLE EARLY THIS MORNING...BUT DAYTIME MIXING AND
DRYING OF THE LOWER LEVELS WILL MOST LIKELY SEAL OFF ANY CHANCES FOR
SPRINKLES TO HIT GROUND. THE MOISTURE WILL REVEAL ITSELF IN A HIGHER
BASED CUMULUS FIELD...BUT ALSO MAY GET STUCK UNDERNEATH AN INVERSION
IN FCST BFR SOUNDINGS. THIS COULD LEAD TO A PERIOD OF MOSTLY CLOUDY
SKIES...BUT REALLY DOUBT THIS WILL HAVE MUCH AFFECT ON RISING TEMPS
REACHING THE MIDDLE 70S MOST AREAS. THIS INVERSION AND DRY SFC TDS
RESULT IN A PRETTY PRONOUNCED CAPPING FOR THE ENTIRE DAY...WITH
LITTLE TO NO CHANCE FOR AFTERNOON CONVECTION.
THERE ARE DIFFERENCES IN HOW THIS LID EVOLVES OVER THE NIGHT...BUT
WE WILL AT LEAST BE TRENDING TOWARD MORE UNSTABLE CONDITIONS. SOME
SHORTWAVE ENERGY/VORTICITY EJECTS FROM AFOREMENTIONED CLOSED LOW
DRIFTING THROUGH SRN CANADA. THIS FORCING ARRIVES LATE EVENING AND
OVERNIGHT. WEAK LOW PRESSURE AND A WARM FRONT LIFT UP TOWARD/INTO
NRN MICHIGAN. THE SAME FCST BFR SOUNDINGS...IN A SCENARIO LIKE
THIS...WOULD LIKELY ERODE/SUPPRESS THE CAP...UNLIKE THE GFS
SUGGESTION. RATHER...WILL GO WITH SHOWERS AND EMBEDDED
GARDEN-VARIETY THUNDERSTORMS DEVELOPING LATE EVENING/OVERNIGHT.
NOTHING SEVERE ANTICIPATED...AS OUR LAPSE RATES AND OVERALL
INSTABILITY WILL NOT MIRROR CURRENT ENVIRONMENT ACROSS THE NRN
PLAINS. WE WILL ONLY HAVE SEVERAL HUNDRED J/KG MUCAPE WITH LAPSE
RATES ALOFT 6-6.5C/KM. THE GREATEST MUCAPE LIKELY TO BE DOWN AROUND
THE MANISTEE/CADILLAC AREAS...ALSO WHERE SOME ADDITIONAL LIFT
ASSISTANCE WILL BE PROVIDED BY UPPER DIVERGENCE IN SOMEWHAT OF A
DOUBLE JET STRUCTURE. WOULD GO WITH LIKELY CHANCES FOR SEEING
PRECIPITATION...BUT BULK OF INSTABILITY AND LLJ FORCING WILL ONCE
AGAIN BE ACROSS SRN WI/NRN IL/SRN LAKE MICHIGAN. THIS COULD BLOCK US
FROM SEEING SOME OF THE ACTION. REGARDLESS...LIKELY TO BE SOME
PRECIPITATION...BEST DESCRIPTION OF WHICH CAN BE PROVIDED BY LATER
SHIFTS AS THE EVENT UNFOLDS.
LOWS TONIGHT WILL LIKELY BE MILD WITH THICKENING CLOUDS...LOWER HALF
OF THE 60S MOST AREAS.
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 303 AM EDT FRI JUL 25 2014
...RAINY END TO THE WEEKEND/COOL TEMPERATURES ON THE WAY FOR THE
START OF NEXT WEEK...
HIGH IMPACT WEATHER POTENTIAL: NOT A BUNCH. CHANCES FOR A FEW
NON-SEVERE THUNDERSTORMS HEADING THROUGH THE WEEKEND.
PATTERN SYNOPSIS/ANTICIPATED EVOLUTION: WHILE STILL PLENTY OF THE
FINER DETAILS TO WORK OUT...MUCH TALKED ABOUT TRANSITION TO A MORE
MERIDIONAL NOAM UPPER FLOW PATTERN STILL ON TARGET TO DEVELOP HEADING
INTO AND THROUGH NEXT WEEK. NO LINGERING DOUBT MICHIGAN WILL BE
CENTERED IN UNSEASONABLY CHILL PRODUCING TROUGH AXIS...WHICH WILL BE
A SLOW ONE TO DEPART ONCE IT DEVELOPS. PLAYERS FOR SUCH UNUSUAL
DEVELOPMENTS ALREADY ON THE TABLE...WITH LARGE NORTHERN QUEBEC GYRE
SIMPLY STUCK IN PLACE...ALL THE WHILE STRONG PACIFIC SHORTWAVE MAKES
STEADY EAST PROGRESS ACROSS THE SOUTHERN CANADIAN ROCKIES. THE
LATTER WILL SIMPLY REINFORCE AND EXTEND THE FORMER AS IT
SLING-SHOTS AROUND IT THROUGH EARLY NEXT WEEK. COMBINE THAT WITH
DEVELOPMENT OF FULLY MATURE GULF OF ALASKA TROUGH/WEST NOAM RIDGE
COUPLET (NOT TO MENTION ONE REALLY AMPLIFIED ATLANTIC RIDGE)...AND
ONE CAN SEE WHY A PATTERN MUCH MORE RESEMBLING THE COOL SEASON IS
EXPECTED.
PRIMARY FORECAST CONCERNS/CHALLENGES: TEMPERATURE TRENDS THROUGHOUT
AND EVOLUTION OF PERIODIC RAIN CHANCES. THUNDERSTORM POTENTIAL AND
INTENSITY WILL ALSO NEED ADDRESSING THIS WEEKEND.
DETAILS: SATURDAY CONTINUES TO REMAIN A CHALLENGE...WITH TIGHT
THETA-E GRADIENT AND SURGE OF BEST UPPER JET FORCING EXITING STAGE
RIGHT RATHER QUICKLY DURING THE MORNING. LEFT BEHIND WILL BE A MUCH
MORE MOIST LOW LEVEL AIRMASS...WITH DEWPOINTS EXPECTED TO BE UP IN
THE MID AND PERHAPS UPPER 60S. KINDA EXPECT WHAT EVER PUNCHES
THROUGH HERE TONIGHT WILL LARGELY EXIT DURING THE MORNING
HOURS...LEAVING NEXT LOW AMP WAVE AND DIURNAL DRIVEN DESTABILIZATION
TO DRIVE ADDITIONAL SHOWER AND STORM DEVELOPMENT. MOISTURE CROSS
SECTIONS SHOW GOOD TO EXCELLENT MOISTURE DEPTH UP THROUGH H7...WITH
AGGRESSIVE DRYING ABOVE THIS LAYER. MANIPULATING MODEL DERIVED
SOUNDINGS WITH ANTICIPATED DEWPOINTS/TEMPERATURES DOES YIELD
DEVELOPMENT OF UPWARDS OF 1K-1.5K J/KG OF ML CAPE DURING THE
AFTERNOON. THINK THIS MIGHT BE A TOUCH AGGRESSIVE...EXPECTING LOW
LEVELS TO BE NOT QUITE AS SATURATED AS GUIDANCE WOULD SUGGEST. WHILE
BEST DYNAMICS WILL HAVE EXITED...NOT ALL IS LOST...WITH MID LEVEL
JET ROTATING THROUGH THE SOUTHWEST LAKES...COMBINING WITH LAKE
INDUCED LOW LEVEL CONVERGENCE /PARTICULARLY IN NORTHEAST LOWER AND
INTERIOR EASTERN UPPER MICHIGAN/ AND SAID WEAK WAVE. ABOVE
DEFINITELY SUPPORTS SOME ADDITIONAL CONVECTIVE POTENTIAL...
ESPECIALLY IN CLIMATOLOGICALLY FAVORED AREAS. INHERITED FORECAST
ALREADY WELL TRENDED IN THIS DIRECTION...WITH ONLY SOME MASSAGING
NEEDED TO POP/WEATHER GRID. DECENT DEEP LAYER SHEAR OF 30 TO 40
KNOTS LARGELY OFFSET BY LIMITED MID LEVEL LAPSE RATES AND SKINNY
CAPE PROFILE UP THROUGH HAIL GROWTH ZONE. SO...IF STORMS CAN DEVELOP
(A BIG IF)...WOULD EXPECT THEM TO REMAIN BELOW SEVERE LIMITS.
LOSS OF INSTABILITY AND RAPID APPROACH OF SHORTWAVE RIDGING EXPECTED
TO BRING A MOSTLY DRY SATURDAY NIGHT. RATHER VIGOROUS CURRENT
SOUTHERN CANADA WAVE QUICKLY FOLLOWS FOR SUNDAY...AND WHEN COMBINED
WITH GOOD SLUG OF LEFT EXIT REGION UPPER JET DYNAMICS...LOOKS TO
BRING A RATHER WIDESPREAD SHOWER EVENT SUNDAY INTO SUNDAY NIGHT.
SYSTEM EVEN LOOKS TO TAKE ON COLD SEASON CHARACTERISTICS...WITH MORE
STEADY RAIN POTENTIAL IN FAVORED NORTH SIDE DEFORMATION FIELD. SOME
THUNDER THREAT REMAINS SUNDAY WITH OPPORTUNITY FOR SOME
DESTABILIZATION BEFORE BETTER FORCING ARRIVES.
TROUGHING DIGS IN AND STAYS THERE-ON-AFTER...PERHAPS LASTING THROUGH
ALL OF NEXT WEEK. COLDEST ANOMALIES EXPECTED TO SLIDE JUST OFF TO
OUR NORTHEAST. THAT SAID...COLD AIR ADVECTION ON FRONT SIDE OF
SPRAWLING NORTHERN PLAINS HIGH WILL BE IMPRESSIVE INDEED...ONCE
AGAIN NOT ALLOWING TEMPERATURES TO GET OUT OF THE 60S ON MONDAY. A
VERY SLOW MODERATION TO FOLLOW...WITH HIGHS WARMING A FEW DEGREES
EACH DAY THROUGH THURSDAY (EVEN BY THURSDAY...HIGHS WILL STILL BE A
FEW DEGREES BELOW NORMAL). DESPITE TROUGHING...JUST NOT OVERLY
IMPRESSED WITH RAIN CHANCES AFTER SUNDAY NIGHTS WAVE PASSAGE. DEEP
LAYER FLOW WILL REMAIN NORTH TO NORTHWEST...AND MID LEVEL
TEMPERATURE REALLY NEVER GET TOO COLD...REACHING THE NEGATIVE UPPER
TEENS AT H5 LATER MONDAY INTO TUESDAY. OF COURSE...ANY WAVES
ROTATING THROUGH WILL ONLY HELP THE SHOWER CAUSE...BUT TIMING AND
MAGNITUDE OF SUCH NOT POSSIBLE TO DETERMINE JUST YET. NO REASON TO
CHANGE THAT WHICH WAS INHERITED...FEATURING JUST ISOLATED/LOW CHANCE
SHOWER POTENTIAL DURING THE DAYTIME HOURS. THIS WILL CHANGE...OF
COURSE...BUT PLENTY OF TIME TO FIGURE THOSE DETAILS OUT IN THE
COMING DAYS.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON)
ISSUED AT 201 PM EDT FRI JUL 25 2014
FOR THE NEXT 18 HOURS (THROUGH 12Z), IT LOOKS LIKE THE DRY AIR
UNDER THE SFC HIGH SHOULD KEEP VFR CONDITIONS OVER N LOWER MI.
HOWEVER, AROUND 12Z SATURDAY, THE WARM FRONT, ASSOCIATED WITH THE
SFC LOW THAT WILL BE NEAR LAKE WINNIPEG, WILL MOVE THROUGH THE
FORECAST AREA, BRINGING MAINLY RAIN SHOWERS AND MVFR CIGS, WITH
SOME POSSIBLE MVFR VSBYS DURING THE MORNING.
&&
.MARINE...
ISSUED AT 303 AM EDT FRI JUL 25 2014
SW WINDS WILL INCREASE HEADING THROUGH TONIGHT...AHEAD OF SFC LOW
PRESSURE AND A WARM FRONT...WHICH WILL BRING AREAS OF SHOWERS AND
GARDEN-VARIETY STORMS TO THE GREAT LAKES. NOTHING SEVERE....AND
WINDS TO REMAIN ABOVE ADVISORY LEVELS. EXPECTING NO MORE THAN
20KTS..WHICH WILL LARGELY RESIDE ACROSS LAKE MICHIGAN. WINDS REMAIN
UNDER ADVISORY LEVELS SATURDAY AND SUNDAY IN WEAK GRADIENT. ANOTHER
SFC LOW CROSSES SUNDAY MORNING WITH A BETTER CHANCE FOR SHOWERS AND
STORMS...AND MUCH COOLER AIR SET TO ARRIVE THROUGH THE DAY SUNDAY
AND SUNDAY NIGHT.
&&
.APX WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LH...NONE.
LM...NONE.
LS...NONE.
&&
$$
UPDATE...JL
SYNOPSIS...MSB
SHORT TERM...SMD
LONG TERM...MSB
AVIATION...JL
MARINE...SMD
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
131 PM EDT FRI JUL 25 2014
.UPDATE...
ISSUED AT 912 AM EDT FRI JUL 25 2014
ALTHOUGH INFLUX OF MSTR IN SW FLOW BTWN HI PRES IN THE MID ATLANTIC
STATES AND FALLING MSLP IN THE PLAINS ASSOCIATED WITH CLOSED H5 LO
MOVING INTO SASKATCHEWAN WL ALLOW SCT SHOWERS OVER WRN UPR MI THIS
MRNG TO SPREAD TO THE E THRU THE DAY...LOWERED THE CHC FOR TS GIVEN
HI STABILITY SHOWN ON THE 12Z INL AND ESPECIALLY THE GRB RAOBS AS
WELL AS RUC FCST SDNGS FOR EVEN IRONWOOD THRU 21Z.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 427 AM EDT FRI JUL 25 2014
THERE IS CURRENTLY A SFC RIDGE OVER THE CWA EXTENDING HIGH PRESSURE
OVER THE OHIO VALLEY. THIS RIDGE WILL BE FIGHTING OFF AN APPROACHING
LOW PRESSURE SYSTEM THAT IS CURRENTLY OVER THE SRN PORTION OT THE
ALBERTA/SASKATCHEWAN BORDER. BETWEEN THESE TWO FEATURES IS A 500MB
RIDGE...THE AXIS OF WHICH IS OVER THE ERN DAKOTAS AND INTO MANITOBA.
A SHORTWAVE IS CURRENTLY OVER FAR WRN LAKE SUPERIOR AND WILL MOVE
ALONG THE MI/WI BORDER THIS MORNING. SOME SHOWERS HAVE DEVELOPED
ALONG AND AHEAD OF THE SHORTWAVE...BUT WITH DRY LOW LEVELS HAVE ONLY
SEEN ONE OR TWO SFC OBS WITH VERY LIGHT RAIN...ALTHOUGH VIS REMAINED
10SM AND CIGS WERE AROUND 10KFT WITH THE SHOWERS.
THE SFC RIDGE WILL WEAKEN SOME THROUGH THE DAY WHILE BECOMING MORE
CONFINED TO THE FAR ERN/NRN CWA. MOISTURE WILL INCREASE OVER THE WRN
CWA THROUGH THE DAY SLOWLY...ALLOWING FOR INCREASED CHANCES OF
PRECIP THROUGH THE DAY ADDITIONAL WEAK SHORTWAVE ENERGY MOVES
THROUGH WHILE WAA INCREASES. STILL DO NOT HAVE MORE THAN LOW END
CHANCE POPS. WITH THE LINGERING DRY AIR OVER THE E...KEEP THEM DRY
THROUGH MOST OF THE DAY.
THE CONTINUALLY WEAKENING RIDGE PUSHES COMPLETELY E OF THE CWA FRI
NIGHT AS SHORTWAVE ENERGY AND A SFC TROUGH MOVES INTO THE CENTRAL
CWA BY LATE IN THE NIGHT. MAINTAINED CHANCE POPS INTO FRI NIGHT.
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 451 AM EDT FRI JUL 25 2014
A SOMEWHAT ACTIVE WEATHER PATTERN WILL BE IN PLACE ACROSS THE REGION
THROUGH THE WEEKEND...WITH A SIGNIFICANT COOLDOWN STARTING SUNDAY
AND EXTENDING INTO NEXT WEEK.
ON SATURDAY...THE FORECAST AREA WILL REMAIN UNDER ZONAL W-NW FLOW
ALOFT WITH THE LEFT EXIT REGION OF THE JET AND ASSOCIATED SHORT
WAVE EXITING TO THE EAST. ANY REMAINING SHOWER ACTIVITY FROM FRI
NIGHT SHOULD EXIT AS WELL AS DRY ADVECTION MOVES ACROSS THE AREA.
THIS WILL ALLOW FOR CLEARING SKIES WITH TEMPERATURES TO WARM INTO
THE MID-UPPER 70S ACROSS THE AREA. ALL THE NUMERICAL GUIDANCE
SUGGEST THAT INSTABILITY WILL INCREASE ACROSS THE EASTERN HALF OF
THE FORECAST AREA DURING THE AFTERNOON IN RESPONSE TO THE DIURNAL
HEATING. ALTHOUGH THE FORECAST CAPE VALUES OF 1000-2000 J/KG IS
LIKELY TOO HIGH DUE TO THE NORMAL HIGH BIAS OF SFC DEW
POINTS...THERE WILL LIKELY STILL BE INSTABILITY OF AT LEAST 1000
J/KG DURING THE LATE MORNING/AFTERNOON SIMPLY DUE TO THE STEEPER
LAPSE RATES ALOFT OF 6.5 C/KM. AS SUCH...HAVE OPTED TO MAINTAIN
CHANCE POPS ACROSS THE EASTERN LAKE BREEZE AREAS DURING THE
AFTERNOON HOURS ESPECIALLY WITH THE NAM AND GFS KEEPING THE LEFT
EXIT REGION OF THE JET AND ASSOCIATED WEAK Q-VECTOR CONVERGENCE IN
THIS AREA DURING THE AFTERNOON. THE BIG LIMITING FACTOR FOR MORE
WIDESPREAD CONVECTION WILL BE THE DRY AIR ALOFT...AND LACK OF
SIGNIFICANT LOW LEVEL FORCING OTHER THAN THE LAKE BREEZE ACTIVITY.
THIS AGREES WELL WITH THE HIGH RES NUMERICAL GUIDANCE THAT SUGGEST A
FEW STORMS ALONG THE LAKE BREEZE DURING THE DAY.
ON SATURDAY NIGHT INTO SUNDAY...THE UPPER LOW CURRENTLY OVER ALBERTA
WILL MOVE TOWARD THE AREA. MEANWHILE...THE UPPER LOW NE OF JAMES BAY
WILL RETROGRADE SLIGHTLY TO THE WEST AND SOUTH. THESE TWO FEATURES
WILL ALLOW FOR THE FRONT TO THE NORTH OF THE AREA TO MOVE ACROSS THE
REGION LATE SAT NIGHT INTO SUNDAY MORNING. AS THIS OCCURS...LOW
PRESSURE ASSOCIATED WITH THE UPPER LOW TO THE WEST WILL MOVE ALONG
THE FRONT ON SAT NIGHT INTO SUNDAY...TRACKING SOUTH OF THE AREA.
SHOWER AND ISOLATED STORMS WILL MOVE INTO THE AREA LATER SAT NIGHT
AHEAD OF THE UPPER LOW...THEN SPREAD ACROSS THE ENTIRE FORECAST AREA
ON SUNDAY. SUNDAY SHOULD END UP BEING A FAIRLY COOL AND DAMP DAY
WITH A BRISK /AT LEAST FOR SUMMER/ NORTH WIND. TEMPERATURES WILL
REMAIN FAIRLY STEADY IN THE 60S ACROSS THE AREA. IN FACT...IT WOULD
NOT BE SURPRISING IF TEMPS WILL FALL DURING THE DAY ESPECIALLY
CLOSER TO LAKE SUPERIOR AS 850MB TEMPS DROP TO 10C BY SUN EVENING.
THE GOOD NEWS IS THAT THE RAIN SHOULD RAPIDLY END LATE SUN AFTERNOON
INTO SUNDAY EVENING AS THE LOW MOVES EAST OF THE AREA. HOWEVER...BY
MONDAY MORNING 850MB TEMPS WILL DROP TO +6C WHICH WILL ALLOW FOR A
COOL NIGHT SUNDAY NIGHT. MONDAY WILL BE TRANQUIL AS WELL WITH STABLE
NORTH WINDS AND BUILDING HIGH PRESSURE ACROSS THE UPPER GREAT LAKES.
FOR THE TUE-THU TIME PERIOD...THE UPPER GREAT LAKES WILL REMAIN
BELOW NORMAL WITH THE DEEP TROUGH PERSISTING ACROSS THE EASTERN HALF
OF THE U.S. THROUGH THE PERIOD. THE UPPER LOW JUST EAST OF HUDSON
BAY WILL REMAIN FAIRLY STATIONARY THROUGH THE PERIOD. WEAK UPPER
LEVEL SHORT WAVES WILL ROTATE AROUND THE UPPER LOW AND ACROSS THE
AREA...WHICH WILL MAKE TIMING OF PRECIPITATION SOMEWHAT DIFFICULT.
HOWEVER...WITH THE COLD TEMPERATURES ALOFT COMBINED WITH FAIRLY
FREQUENT DISTURBANCES ALOFT...EXPECT THE BEST CHANCES FOR SHOWERS
AND STORMS TO BE DURING THE PEAK HEATING HOURS IN THE AFTERNOON AND
EARLY EVENING HOURS EACH DAY. OTHERWISE...TEMPERATURES WILL REMAIN
BELOW NORMAL THROUGH THE PERIOD.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON)
ISSUED AT 129 PM EDT FRI JUL 25 2014
WITH INFLUX OF MOISTER AIR IN LLVL SW FLOW AND APRCH OF AN UPPER
DISTURBANCE...EXPECT SHRA AND AREA OF MVFR CLDS NEAR IWD TO
OVERSPREAD CMX AND SAW BY THIS EVNG. WITH SOME DRYING ALF LATE TNGT
THAT WL END THE SHOWERS...EXPECT IFR CONDITIONS TO DVLP IN THE
PRESENCE OF DIURNAL COOLING. LIFR CONDITIONS ARE NOT OUT OF THE
QUESTION. THE ARRIVAL OF DRIER AIR AND DAYTIME WL RESULT IN
IMPROVEMENT TO VFR ON SAT. THIS PROCESS WL BE SLOWEST AT CMX WITH AN
UPSLOPE W WIND.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 427 AM EDT FRI JUL 25 2014
EXPECT WINDS UNDER 15 KTS THRU SAT NIGHT WITH RELATIVELY WEAK PRES
GRADIENT DOMINATING THE UPPER LAKES. STRONGER N WINDS UP TO 20-25
KTS ARE POSSIBLE ON SUN INTO MON AS COOLER AIR INVADES THE AREA
UNDER TIGHTER GRADIENT BETWEEN HI PRES MOVING INTO THE NORTHERN
PLAINS AND LO PRES OVER THE SE GREAT LAKES. WINDS WILL DIMINISH ON
TUE AND BACK TOWARD THE W WITH CLOSER APPROACH OF HI PRES FROM THE
PLAINS.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
UPDATE...KC
SHORT TERM...TITUS
LONG TERM...MRD
AVIATION...KC
MARINE...TITUS
AREA FORECAST DISCUSSION
NWS GAYLORD MI
957 AM EDT FRI JUL 25 2014
.SYNOPSIS...
ISSUED AT 303 AM EDT FRI JUL 25 2014
HIGH PRESSURE WILL GIVE WAY TO A FAST MOVING SYSTEM TONIGHT AND
SATURDAY. CLOUDS WILL BE ON THE INCREASE TODAY...WITH A CHANCE FOR
SHOWERS AND A FEW THUNDERSTORMS TONIGHT INTO THE START OF THE
WEEKEND. A MUCH STRONGER SYSTEM WILL ARRIVE TO END THE WEEKEND...
BRINGING BETTER POTENTIAL FOR SHOWERS SUNDAY AND SUNDAY NIGHT. A
RETURN TO MUCH BELOW NORMAL TEMPERATURES ON MONDAY...WITH ONLY A
SLOW MODERATION EXPECTED THROUGH THE REMAINDER OF THE WEEK.
&&
.UPDATE...
ISSUED AT 948 AM EDT FRI JUL 25 2014
RAIN SHOWERS OVER WISCONSIN ARE TRYING TO MAKE THEIR WAY INTO N
LOWER FOR THE AFTERNOON. WILL BE WATCHING THESE AS THEY SEEMED TO
BE HIGH BASED SHOWERS (9000-10000FT BASES) WITH SCT DECKS DOWN
LOWER. KAPX 12Z SOUNDING SHOWED LOTS OF DRY AIR, BUT ACROSS THE
LAKE KGRB 12Z SOUNDING SHOWED SOME MOISTENING BETWEEN 925 MB AND
750 MB. HOWEVER, BOTH SOUNDINGS SHOWED PRONOUNCED CAPPING
INVERSION AROUND 750 MB. SO WE ARE IN A WAIT AND SEE GAME, GUT
FEELING IS THAT WE SEE SOME SPRINKLES IN THE AFTERNOON, BUT NO
MEASURABLE RAIN SHOWERS. MAY HAVE TO BUMP THE POPS UP TO ISOLATED
SHOWERS IN NW LOWER DEPENDING ON THE TRENDS.
&&
.SHORT TERM...(TODAY THROUGH TONIGHT)
ISSUED AT 303 AM EDT FRI JUL 25 2014
...MORE CLOUDS AND A SHADE WARMER WITH STORM CHANCES TONIGHT...
IMPACTS: LIGHTNING...BUT NO SEVERE WEATHER EXPECTED.
CURRENT WEATHER AND SYNOPTIC PATTERN:
BROAD UPPER RIDGING SEEN OVER THE SW PART OF THE COUNTRY WHILE
TROUGHING IS STILL THE THEME OVER THE EASTERN CONUS. THE RIDGING HAS
BEEN SQUASHED DUE TO A WRAPPED UP CLOSED LOW DRIFTS ACROSS SW
CANADA. THIS HAS INDUCED LOW PRESSURE OVER EASTERN CANADA AND THE
NRN PLAINS. AN AXIS OF DEEP THETA-E AIR...LEADING EDGE OF STEEP
LAPSE RATES ALOFT (6.5C/KM-7.5C/KM) AND LLJ (45-55KT) CONVERGENCE
AHEAD OF THE PLAINS SFC LOW HAS RESULTED IN POCKETS OF SHOWERS AND
STORMS IN THE DAKOTAS DOWN TO NE. CLOSER TO HOME...AREA VAD WIND
PROFILES AND RUC ANALYSIS SHOWING A TROUGH AXIS AND H8 MOISTURE
ADVECTION FROM THE ARROWHEAD OF MN DOWN THROUGH WISCONSIN. THERE
WERE A FEW ELEVATED RETURNS...BUT ONLY A FEW SPRINKLES HITTING
GROUND PER AREA OBS. OVER NRN MICHIGAN...WE ARE STILL UNDER THE
INFLUENCE OF SFC HIGH PRESSURE...BUT THOSE SAME VAD WIND PROFILES
SHOW THAT THIS HAS SHIFTED JUST EAST OF US WITH A RETURN TO A SW
WIND. AIR MASS IS STILL QUITE DRY WITH PWATS RELATIVELY LOWER THAN
ANYWHERE NEARBY. ONLY A BAND OF HIGHER LEVEL CLOUD STREAMING DOWN
THROUGH THE NW FLOW ALOFT. THE DRY AIR AND MOSTLY CLEAR SKIES HAVE
ALLOWED TEMPERATURES TO FALL INTO THE LOWER HALF OF THE 40S IN THE
LOW LYING AREAS...WHILE COASTAL AREAS AND SOME EXPOSED HIGHER
TERRAIN ARE IN THE LOWER HALF OF THE 50S.
SYNOPTIC PATTERN/WEATHER EVOLUTION:
THE SFC HIGH GRADUALLY SINKS OFF TO THE SE TODAY...WHILE THE
SOUTHERLY PRESSURE GRADIENT TIGHTENS AND DRAWS IN MORE LOW LEVEL
MOISTURE THROUGH THE DAY AND NIGHT. THE INITIAL H8 TROUGH AND
MOISTURE ADVECTION WILL DRIFT OVERHEAD TODAY...AND MAYBE SOME
SPRINKLES ARE POSSIBLE EARLY THIS MORNING...BUT DAYTIME MIXING AND
DRYING OF THE LOWER LEVELS WILL MOST LIKELY SEAL OFF ANY CHANCES FOR
SPRINKLES TO HIT GROUND. THE MOISTURE WILL REVEAL ITSELF IN A HIGHER
BASED CUMULUS FIELD...BUT ALSO MAY GET STUCK UNDERNEATH AN INVERSION
IN FCST BFR SOUNDINGS. THIS COULD LEAD TO A PERIOD OF MOSTLY CLOUDY
SKIES...BUT REALLY DOUBT THIS WILL HAVE MUCH AFFECT ON RISING TEMPS
REACHING THE MIDDLE 70S MOST AREAS. THIS INVERSION AND DRY SFC TDS
RESULT IN A PRETTY PRONOUNCED CAPPING FOR THE ENTIRE DAY...WITH
LITTLE TO NO CHANCE FOR AFTERNOON CONVECTION.
THERE ARE DIFFERENCES IN HOW THIS LID EVOLVES OVER THE NIGHT...BUT
WE WILL AT LEAST BE TRENDING TOWARD MORE UNSTABLE CONDITIONS. SOME
SHORTWAVE ENERGY/VORTICITY EJECTS FROM AFOREMENTIONED CLOSED LOW
DRIFTING THROUGH SRN CANADA. THIS FORCING ARRIVES LATE EVENING AND
OVERNIGHT. WEAK LOW PRESSURE AND A WARM FRONT LIFT UP TOWARD/INTO
NRN MICHIGAN. THE SAME FCST BFR SOUNDINGS...IN A SCENARIO LIKE
THIS...WOULD LIKELY ERODE/SUPPRESS THE CAP...UNLIKE THE GFS
SUGGESTION. RATHER...WILL GO WITH SHOWERS AND EMBEDDED
GARDEN-VARIETY THUNDERSTORMS DEVELOPING LATE EVENING/OVERNIGHT.
NOTHING SEVERE ANTICIPATED...AS OUR LAPSE RATES AND OVERALL
INSTABILITY WILL NOT MIRROR CURRENT ENVIRONMENT ACROSS THE NRN
PLAINS. WE WILL ONLY HAVE SEVERAL HUNDRED J/KG MUCAPE WITH LAPSE
RATES ALOFT 6-6.5C/KM. THE GREATEST MUCAPE LIKELY TO BE DOWN AROUND
THE MANISTEE/CADILLAC AREAS...ALSO WHERE SOME ADDITIONAL LIFT
ASSISTANCE WILL BE PROVIDED BY UPPER DIVERGENCE IN SOMEWHAT OF A
DOUBLE JET STRUCTURE. WOULD GO WITH LIKELY CHANCES FOR SEEING
PRECIPITATION...BUT BULK OF INSTABILITY AND LLJ FORCING WILL ONCE
AGAIN BE ACROSS SRN WI/NRN IL/SRN LAKE MICHIGAN. THIS COULD BLOCK US
FROM SEEING SOME OF THE ACTION. REGARDLESS...LIKELY TO BE SOME
PRECIPITATION...BEST DESCRIPTION OF WHICH CAN BE PROVIDED BY LATER
SHIFTS AS THE EVENT UNFOLDS.
LOWS TONIGHT WILL LIKELY BE MILD WITH THICKENING CLOUDS...LOWER HALF
OF THE 60S MOST AREAS.
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 303 AM EDT FRI JUL 25 2014
...RAINY END TO THE WEEKEND/COOL TEMPERATURES ON THE WAY FOR THE
START OF NEXT WEEK...
HIGH IMPACT WEATHER POTENTIAL: NOT A BUNCH. CHANCES FOR A FEW
NON-SEVERE THUNDERSTORMS HEADING THROUGH THE WEEKEND.
PATTERN SYNOPSIS/ANTICIPATED EVOLUTION: WHILE STILL PLENTY OF THE
FINER DETAILS TO WORK OUT...MUCH TALKED ABOUT TRANSITION TO A MORE
MERIDIONAL NOAM UPPER FLOW PATTERN STILL ON TARGET TO DEVELOP HEADING
INTO AND THROUGH NEXT WEEK. NO LINGERING DOUBT MICHIGAN WILL BE
CENTERED IN UNSEASONABLY CHILL PRODUCING TROUGH AXIS...WHICH WILL BE
A SLOW ONE TO DEPART ONCE IT DEVELOPS. PLAYERS FOR SUCH UNUSUAL
DEVELOPMENTS ALREADY ON THE TABLE...WITH LARGE NORTHERN QUEBEC GYRE
SIMPLY STUCK IN PLACE...ALL THE WHILE STRONG PACIFIC SHORTWAVE MAKES
STEADY EAST PROGRESS ACROSS THE SOUTHERN CANADIAN ROCKIES. THE
LATTER WILL SIMPLY REINFORCE AND EXTEND THE FORMER AS IT
SLING-SHOTS AROUND IT THROUGH EARLY NEXT WEEK. COMBINE THAT WITH
DEVELOPMENT OF FULLY MATURE GULF OF ALASKA TROUGH/WEST NOAM RIDGE
COUPLET (NOT TO MENTION ONE REALLY AMPLIFIED ATLANTIC RIDGE)...AND
ONE CAN SEE WHY A PATTERN MUCH MORE RESEMBLING THE COOL SEASON IS
EXPECTED.
PRIMARY FORECAST CONCERNS/CHALLENGES: TEMPERATURE TRENDS THROUGHOUT
AND EVOLUTION OF PERIODIC RAIN CHANCES. THUNDERSTORM POTENTIAL AND
INTENSITY WILL ALSO NEED ADDRESSING THIS WEEKEND.
DETAILS: SATURDAY CONTINUES TO REMAIN A CHALLENGE...WITH TIGHT
THETA-E GRADIENT AND SURGE OF BEST UPPER JET FORCING EXITING STAGE
RIGHT RATHER QUICKLY DURING THE MORNING. LEFT BEHIND WILL BE A MUCH
MORE MOIST LOW LEVEL AIRMASS...WITH DEWPOINTS EXPECTED TO BE UP IN
THE MID AND PERHAPS UPPER 60S. KINDA EXPECT WHAT EVER PUNCHES
THROUGH HERE TONIGHT WILL LARGELY EXIT DURING THE MORNING
HOURS...LEAVING NEXT LOW AMP WAVE AND DIURNAL DRIVEN DESTABILIZATION
TO DRIVE ADDITIONAL SHOWER AND STORM DEVELOPMENT. MOISTURE CROSS
SECTIONS SHOW GOOD TO EXCELLENT MOISTURE DEPTH UP THROUGH H7...WITH
AGGRESSIVE DRYING ABOVE THIS LAYER. MANIPULATING MODEL DERIVED
SOUNDINGS WITH ANTICIPATED DEWPOINTS/TEMPERATURES DOES YIELD
DEVELOPMENT OF UPWARDS OF 1K-1.5K J/KG OF ML CAPE DURING THE
AFTERNOON. THINK THIS MIGHT BE A TOUCH AGGRESSIVE...EXPECTING LOW
LEVELS TO BE NOT QUITE AS SATURATED AS GUIDANCE WOULD SUGGEST. WHILE
BEST DYNAMICS WILL HAVE EXITED...NOT ALL IS LOST...WITH MID LEVEL
JET ROTATING THROUGH THE SOUTHWEST LAKES...COMBINING WITH LAKE
INDUCED LOW LEVEL CONVERGENCE /PARTICULARLY IN NORTHEAST LOWER AND
INTERIOR EASTERN UPPER MICHIGAN/ AND SAID WEAK WAVE. ABOVE
DEFINITELY SUPPORTS SOME ADDITIONAL CONVECTIVE POTENTIAL...
ESPECIALLY IN CLIMATOLOGICALLY FAVORED AREAS. INHERITED FORECAST
ALREADY WELL TRENDED IN THIS DIRECTION...WITH ONLY SOME MASSAGING
NEEDED TO POP/WEATHER GRID. DECENT DEEP LAYER SHEAR OF 30 TO 40
KNOTS LARGELY OFFSET BY LIMITED MID LEVEL LAPSE RATES AND SKINNY
CAPE PROFILE UP THROUGH HAIL GROWTH ZONE. SO...IF STORMS CAN DEVELOP
(A BIG IF)...WOULD EXPECT THEM TO REMAIN BELOW SEVERE LIMITS.
LOSS OF INSTABILITY AND RAPID APPROACH OF SHORTWAVE RIDGING EXPECTED
TO BRING A MOSTLY DRY SATURDAY NIGHT. RATHER VIGOROUS CURRENT
SOUTHERN CANADA WAVE QUICKLY FOLLOWS FOR SUNDAY...AND WHEN COMBINED
WITH GOOD SLUG OF LEFT EXIT REGION UPPER JET DYNAMICS...LOOKS TO
BRING A RATHER WIDESPREAD SHOWER EVENT SUNDAY INTO SUNDAY NIGHT.
SYSTEM EVEN LOOKS TO TAKE ON COLD SEASON CHARACTERISTICS...WITH MORE
STEADY RAIN POTENTIAL IN FAVORED NORTH SIDE DEFORMATION FIELD. SOME
THUNDER THREAT REMAINS SUNDAY WITH OPPORTUNITY FOR SOME
DESTABILIZATION BEFORE BETTER FORCING ARRIVES.
TROUGHING DIGS IN AND STAYS THERE-ON-AFTER...PERHAPS LASTING THROUGH
ALL OF NEXT WEEK. COLDEST ANOMALIES EXPECTED TO SLIDE JUST OFF TO
OUR NORTHEAST. THAT SAID...COLD AIR ADVECTION ON FRONT SIDE OF
SPRAWLING NORTHERN PLAINS HIGH WILL BE IMPRESSIVE INDEED...ONCE
AGAIN NOT ALLOWING TEMPERATURES TO GET OUT OF THE 60S ON MONDAY. A
VERY SLOW MODERATION TO FOLLOW...WITH HIGHS WARMING A FEW DEGREES
EACH DAY THROUGH THURSDAY (EVEN BY THURSDAY...HIGHS WILL STILL BE A
FEW DEGREES BELOW NORMAL). DESPITE TROUGHING...JUST NOT OVERLY
IMPRESSED WITH RAIN CHANCES AFTER SUNDAY NIGHTS WAVE PASSAGE. DEEP
LAYER FLOW WILL REMAIN NORTH TO NORTHWEST...AND MID LEVEL
TEMPERATURE REALLY NEVER GET TOO COLD...REACHING THE NEGATIVE UPPER
TEENS AT H5 LATER MONDAY INTO TUESDAY. OF COURSE...ANY WAVES
ROTATING THROUGH WILL ONLY HELP THE SHOWER CAUSE...BUT TIMING AND
MAGNITUDE OF SUCH NOT POSSIBLE TO DETERMINE JUST YET. NO REASON TO
CHANGE THAT WHICH WAS INHERITED...FEATURING JUST ISOLATED/LOW CHANCE
SHOWER POTENTIAL DURING THE DAYTIME HOURS. THIS WILL CHANGE...OF
COURSE...BUT PLENTY OF TIME TO FIGURE THOSE DETAILS OUT IN THE
COMING DAYS.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SATURDAY MORNING)
ISSUED AT 609 AM EDT FRI JUL 25 2014
...MAINLY VFR WITH CHANCES FOR SHOWERS AND STORMS TONIGHT...
SFC HIGH PRESSURE HAS EXITED SOUTHEAST ALLOWING FOR A LIGHT SW
RETURN FLOW. THIS GRADIENT TIGHTENS A TOUCH TODAY WITH GUSTS UP TO
15-18KTS EXPECTED...MAINLY ACROSS NW LOWER. CUMULUS AND SOME
HIGHER CLOUD EXPECTED TO ROLL ON THROUGH TODAY AND POSSIBLY GET
STUCK UNDERNEATH AN INVERSION FOR A PERIOD OF MORE CLOUDY
CONDITIONS. WEAK LOW PRESSURE AND A WARM FRONT ARRIVE TONIGHT WITH
THE CHANCE FOR SHOWERS AND STORMS AHEAD OF IT. EXACT EVOLUTION OF
THE PRECIPITATION NEBULOUS RIGHT NOW...WILL INCLUDE A VCSH FOR THE
NIGHT.
NO SEVERE WEATHER ANTICIPATED. BRIEF HEAVY RAIN AND LIGHTNING
HOWEVER.
&&
.MARINE...
ISSUED AT 303 AM EDT FRI JUL 25 2014
SW WINDS WILL INCREASE HEADING THROUGH TONIGHT...AHEAD OF SFC LOW
PRESSURE AND A WARM FRONT...WHICH WILL BRING AREAS OF SHOWERS AND
GARDEN-VARIETY STORMS TO THE GREAT LAKES. NOTHING SEVERE....AND
WINDS TO REMAIN ABOVE ADVISORY LEVELS. EXPECTING NO MORE THAN
20KTS..WHICH WILL LARGELY RESIDE ACROSS LAKE MICHIGAN. WINDS REMAIN
UNDER ADVISORY LEVELS SATURDAY AND SUNDAY IN WEAK GRADIENT. ANOTHER
SFC LOW CROSSES SUNDAY MORNING WITH A BETTER CHANCE FOR SHOWERS AND
STORMS...AND MUCH COOLER AIR SET TO ARRIVE THROUGH THE DAY SUNDAY
AND SUNDAY NIGHT.
&&
.APX WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LH...NONE.
LM...NONE.
LS...NONE.
&&
$$
UPDATE...JL
SYNOPSIS...MSB
SHORT TERM...SMD
LONG TERM...MSB
AVIATION...SMD
MARINE...SMD
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
912 AM EDT FRI JUL 25 2014
.UPDATE...
ISSUED AT 912 AM EDT FRI JUL 25 2014
ALTHOUGH INFLUX OF MSTR IN SW FLOW BTWN HI PRES IN THE MID ATLANTIC
STATES AND FALLING MSLP IN THE PLAINS ASSOCIATED WITH CLOSED H5 LO
MOVING INTO SASKATCHEWAN WL ALLOW SCT SHOWERS OVER WRN UPR MI THIS
MRNG TO SPREAD TO THE E THRU THE DAY...LOWERED THE CHC FOR TS GIVEN
HI STABILITY SHOWN ON THE 12Z INL AND ESPECIALLY THE GRB RAOBS AS
WELL AS RUC FCST SDNGS FOR EVEN IRONWOOD THRU 21Z.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 427 AM EDT FRI JUL 25 2014
THERE IS CURRENTLY A SFC RIDGE OVER THE CWA EXTENDING HIGH PRESSURE
OVER THE OHIO VALLEY. THIS RIDGE WILL BE FIGHTING OFF AN APPROACHING
LOW PRESSURE SYSTEM THAT IS CURRENTLY OVER THE SRN PORTION OT THE
ALBERTA/SASKATCHEWAN BORDER. BETWEEN THESE TWO FEATURES IS A 500MB
RIDGE...THE AXIS OF WHICH IS OVER THE ERN DAKOTAS AND INTO MANITOBA.
A SHORTWAVE IS CURRENTLY OVER FAR WRN LAKE SUPERIOR AND WILL MOVE
ALONG THE MI/WI BORDER THIS MORNING. SOME SHOWERS HAVE DEVELOPED
ALONG AND AHEAD OF THE SHORTWAVE...BUT WITH DRY LOW LEVELS HAVE ONLY
SEEN ONE OR TWO SFC OBS WITH VERY LIGHT RAIN...ALTHOUGH VIS REMAINED
10SM AND CIGS WERE AROUND 10KFT WITH THE SHOWERS.
THE SFC RIDGE WILL WEAKEN SOME THROUGH THE DAY WHILE BECOMING MORE
CONFINED TO THE FAR ERN/NRN CWA. MOISTURE WILL INCREASE OVER THE WRN
CWA THROUGH THE DAY SLOWLY...ALLOWING FOR INCREASED CHANCES OF
PRECIP THROUGH THE DAY ADDITIONAL WEAK SHORTWAVE ENERGY MOVES
THROUGH WHILE WAA INCREASES. STILL DO NOT HAVE MORE THAN LOW END
CHANCE POPS. WITH THE LINGERING DRY AIR OVER THE E...KEEP THEM DRY
THROUGH MOST OF THE DAY.
THE CONTINUALLY WEAKENING RIDGE PUSHES COMPLETELY E OF THE CWA FRI
NIGHT AS SHORTWAVE ENERGY AND A SFC TROUGH MOVES INTO THE CENTRAL
CWA BY LATE IN THE NIGHT. MAINTAINED CHANCE POPS INTO FRI NIGHT.
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 451 AM EDT FRI JUL 25 2014
A SOMEWHAT ACTIVE WEATHER PATTERN WILL BE IN PLACE ACROSS THE REGION
THROUGH THE WEEKEND...WITH A SIGNIFICANT COOLDOWN STARTING SUNDAY
AND EXTENDING INTO NEXT WEEK.
ON SATURDAY...THE FORECAST AREA WILL REMAIN UNDER ZONAL W-NW FLOW
ALOFT WITH THE LEFT EXIT REGION OF THE JET AND ASSOCIATED SHORT
WAVE EXITING TO THE EAST. ANY REMAINING SHOWER ACTIVITY FROM FRI
NIGHT SHOULD EXIT AS WELL AS DRY ADVECTION MOVES ACROSS THE AREA.
THIS WILL ALLOW FOR CLEARING SKIES WITH TEMPERATURES TO WARM INTO
THE MID-UPPER 70S ACROSS THE AREA. ALL THE NUMERICAL GUIDANCE
SUGGEST THAT INSTABILITY WILL INCREASE ACROSS THE EASTERN HALF OF
THE FORECAST AREA DURING THE AFTERNOON IN RESPONSE TO THE DIURNAL
HEATING. ALTHOUGH THE FORECAST CAPE VALUES OF 1000-2000 J/KG IS
LIKELY TOO HIGH DUE TO THE NORMAL HIGH BIAS OF SFC DEW
POINTS...THERE WILL LIKELY STILL BE INSTABILITY OF AT LEAST 1000
J/KG DURING THE LATE MORNING/AFTERNOON SIMPLY DUE TO THE STEEPER
LAPSE RATES ALOFT OF 6.5 C/KM. AS SUCH...HAVE OPTED TO MAINTAIN
CHANCE POPS ACROSS THE EASTERN LAKE BREEZE AREAS DURING THE
AFTERNOON HOURS ESPECIALLY WITH THE NAM AND GFS KEEPING THE LEFT
EXIT REGION OF THE JET AND ASSOCIATED WEAK Q-VECTOR CONVERGENCE IN
THIS AREA DURING THE AFTERNOON. THE BIG LIMITING FACTOR FOR MORE
WIDESPREAD CONVECTION WILL BE THE DRY AIR ALOFT...AND LACK OF
SIGNIFICANT LOW LEVEL FORCING OTHER THAN THE LAKE BREEZE ACTIVITY.
THIS AGREES WELL WITH THE HIGH RES NUMERICAL GUIDANCE THAT SUGGEST A
FEW STORMS ALONG THE LAKE BREEZE DURING THE DAY.
ON SATURDAY NIGHT INTO SUNDAY...THE UPPER LOW CURRENTLY OVER ALBERTA
WILL MOVE TOWARD THE AREA. MEANWHILE...THE UPPER LOW NE OF JAMES BAY
WILL RETROGRADE SLIGHTLY TO THE WEST AND SOUTH. THESE TWO FEATURES
WILL ALLOW FOR THE FRONT TO THE NORTH OF THE AREA TO MOVE ACROSS THE
REGION LATE SAT NIGHT INTO SUNDAY MORNING. AS THIS OCCURS...LOW
PRESSURE ASSOCIATED WITH THE UPPER LOW TO THE WEST WILL MOVE ALONG
THE FRONT ON SAT NIGHT INTO SUNDAY...TRACKING SOUTH OF THE AREA.
SHOWER AND ISOLATED STORMS WILL MOVE INTO THE AREA LATER SAT NIGHT
AHEAD OF THE UPPER LOW...THEN SPREAD ACROSS THE ENTIRE FORECAST AREA
ON SUNDAY. SUNDAY SHOULD END UP BEING A FAIRLY COOL AND DAMP DAY
WITH A BRISK /AT LEAST FOR SUMMER/ NORTH WIND. TEMPERATURES WILL
REMAIN FAIRLY STEADY IN THE 60S ACROSS THE AREA. IN FACT...IT WOULD
NOT BE SURPRISING IF TEMPS WILL FALL DURING THE DAY ESPECIALLY
CLOSER TO LAKE SUPERIOR AS 850MB TEMPS DROP TO 10C BY SUN EVENING.
THE GOOD NEWS IS THAT THE RAIN SHOULD RAPIDLY END LATE SUN AFTERNOON
INTO SUNDAY EVENING AS THE LOW MOVES EAST OF THE AREA. HOWEVER...BY
MONDAY MORNING 850MB TEMPS WILL DROP TO +6C WHICH WILL ALLOW FOR A
COOL NIGHT SUNDAY NIGHT. MONDAY WILL BE TRANQUIL AS WELL WITH STABLE
NORTH WINDS AND BUILDING HIGH PRESSURE ACROSS THE UPPER GREAT LAKES.
FOR THE TUE-THU TIME PERIOD...THE UPPER GREAT LAKES WILL REMAIN
BELOW NORMAL WITH THE DEEP TROUGH PERSISTING ACROSS THE EASTERN HALF
OF THE U.S. THROUGH THE PERIOD. THE UPPER LOW JUST EAST OF HUDSON
BAY WILL REMAIN FAIRLY STATIONARY THROUGH THE PERIOD. WEAK UPPER
LEVEL SHORT WAVES WILL ROTATE AROUND THE UPPER LOW AND ACROSS THE
AREA...WHICH WILL MAKE TIMING OF PRECIPITATION SOMEWHAT DIFFICULT.
HOWEVER...WITH THE COLD TEMPERATURES ALOFT COMBINED WITH FAIRLY
FREQUENT DISTURBANCES ALOFT...EXPECT THE BEST CHANCES FOR SHOWERS
AND STORMS TO BE DURING THE PEAK HEATING HOURS IN THE AFTERNOON AND
EARLY EVENING HOURS EACH DAY. OTHERWISE...TEMPERATURES WILL REMAIN
BELOW NORMAL THROUGH THE PERIOD.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SATURDAY MORNING)
ISSUED AT 744 AM EDT FRI JUL 25 2014
STILL HAVE SIGNIFICANT UNCERTAINTY IN EXACT TIMING/EXTENT OF
POSSIBLE SHOWERS THROUGH THE TAF PERIOD. SUBTLE ENERGY MOVING
THROUGH THE AREA OVER THE NEXT 24 HOURS WILL LEAD TO PERIODS OF
SHOWERS AND THUNDERSTORMS. DRY LOW LEVEL AIRMASS OVER THE AREA
INITIALLY WILL SLOWLY MOISTEN TODAY...SO LEFT PRECIP OUT OF THE
FORECAST THROUGH THIS AFTERNOON. EVEN AT IWD WHERE RADAR SHOWS
DECENT REFLECTIVITIES...LOW LEVEL DRY AIR IS PREVENTING SIGNIFICANT
PRECIP FROM MAKING IT TO THE GROUND...SO JUST PUT A TEMPO FOR -SHRA
THERE THIS MORNING.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 427 AM EDT FRI JUL 25 2014
EXPECT WINDS UNDER 15 KTS THRU SAT NIGHT WITH RELATIVELY WEAK PRES
GRADIENT DOMINATING THE UPPER LAKES. STRONGER N WINDS UP TO 20-25
KTS ARE POSSIBLE ON SUN INTO MON AS COOLER AIR INVADES THE AREA
UNDER TIGHTER GRADIENT BETWEEN HI PRES MOVING INTO THE NORTHERN
PLAINS AND LO PRES OVER THE SE GREAT LAKES. WINDS WILL DIMINISH ON
TUE AND BACK TOWARD THE W WITH CLOSER APPROACH OF HI PRES FROM THE
PLAINS.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
UPDATE...KC
SHORT TERM...TITUS
LONG TERM...MRD
AVIATION...TITUS
MARINE...TITUS
AREA FORECAST DISCUSSION
NWS GAYLORD MI
615 AM EDT FRI JUL 25 2014
.SYNOPSIS...
ISSUED AT 303 AM EDT FRI JUL 25 2014
HIGH PRESSURE WILL GIVE WAY TO A FAST MOVING SYSTEM TONIGHT AND
SATURDAY. CLOUDS WILL BE ON THE INCREASE TODAY...WITH A CHANCE FOR
SHOWERS AND A FEW THUNDERSTORMS TONIGHT INTO THE START OF THE
WEEKEND. A MUCH STRONGER SYSTEM WILL ARRIVE TO END THE WEEKEND...
BRINGING BETTER POTENTIAL FOR SHOWERS SUNDAY AND SUNDAY NIGHT. A
RETURN TO MUCH BELOW NORMAL TEMPERATURES ON MONDAY...WITH ONLY A
SLOW MODERATION EXPECTED THROUGH THE REMAINDER OF THE WEEK.
&&
.SHORT TERM...(TODAY THROUGH TONIGHT)
ISSUED AT 303 AM EDT FRI JUL 25 2014
...MORE CLOUDS AND A SHADE WARMER WITH STORM CHANCES TONIGHT...
IMPACTS: LIGHTNING...BUT NO SEVERE WEATHER EXPECTED.
CURRENT WEATHER AND SYNOPTIC PATTERN:
BROAD UPPER RIDGING SEEN OVER THE SW PART OF THE COUNTRY WHILE
TROUGHING IS STILL THE THEME OVER THE EASTERN CONUS. THE RIDGING HAS
BEEN SQUASHED DUE TO A WRAPPED UP CLOSED LOW DRIFTS ACROSS SW
CANADA. THIS HAS INDUCED LOW PRESSURE OVER EASTERN CANADA AND THE
NRN PLAINS. AN AXIS OF DEEP THETA-E AIR...LEADING EDGE OF STEEP
LAPSE RATES ALOFT (6.5C/KM-7.5C/KM) AND LLJ (45-55KT) CONVERGENCE
AHEAD OF THE PLAINS SFC LOW HAS RESULTED IN POCKETS OF SHOWERS AND
STORMS IN THE DAKOTAS DOWN TO NE. CLOSER TO HOME...AREA VAD WIND
PROFILES AND RUC ANALYSIS SHOWING A TROUGH AXIS AND H8 MOISTURE
ADVECTION FROM THE ARROWHEAD OF MN DOWN THROUGH WISCONSIN. THERE
WERE A FEW ELEVATED RETURNS...BUT ONLY A FEW SPRINKLES HITTING
GROUND PER AREA OBS. OVER NRN MICHIGAN...WE ARE STILL UNDER THE
INFLUENCE OF SFC HIGH PRESSURE...BUT THOSE SAME VAD WIND PROFILES
SHOW THAT THIS HAS SHIFTED JUST EAST OF US WITH A RETURN TO A SW
WIND. AIR MASS IS STILL QUITE DRY WITH PWATS RELATIVELY LOWER THAN
ANYWHERE NEARBY. ONLY A BAND OF HIGHER LEVEL CLOUD STREAMING DOWN
THROUGH THE NW FLOW ALOFT. THE DRY AIR AND MOSTLY CLEAR SKIES HAVE
ALLOWED TEMPERATURES TO FALL INTO THE LOWER HALF OF THE 40S IN THE
LOW LYING AREAS...WHILE COASTAL AREAS AND SOME EXPOSED HIGHER
TERRAIN ARE IN THE LOWER HALF OF THE 50S.
SYNOPTIC PATTERN/WEATHER EVOLUTION:
THE SFC HIGH GRADUALLY SINKS OFF TO THE SE TODAY...WHILE THE
SOUTHERLY PRESSURE GRADIENT TIGHTENS AND DRAWS IN MORE LOW LEVEL
MOISTURE THROUGH THE DAY AND NIGHT. THE INITIAL H8 TROUGH AND
MOISTURE ADVECTION WILL DRIFT OVERHEAD TODAY...AND MAYBE SOME
SPRINKLES ARE POSSIBLE EARLY THIS MORNING...BUT DAYTIME MIXING AND
DRYING OF THE LOWER LEVELS WILL MOST LIKELY SEAL OFF ANY CHANCES FOR
SPRINKLES TO HIT GROUND. THE MOISTURE WILL REVEAL ITSELF IN A HIGHER
BASED CUMULUS FIELD...BUT ALSO MAY GET STUCK UNDERNEATH AN INVERSION
IN FCST BFR SOUNDINGS. THIS COULD LEAD TO A PERIOD OF MOSTLY CLOUDY
SKIES...BUT REALLY DOUBT THIS WILL HAVE MUCH AFFECT ON RISING TEMPS
REACHING THE MIDDLE 70S MOST AREAS. THIS INVERSION AND DRY SFC TDS
RESULT IN A PRETTY PRONOUNCED CAPPING FOR THE ENTIRE DAY...WITH
LITTLE TO NO CHANCE FOR AFTERNOON CONVECTION.
THERE ARE DIFFERENCES IN HOW THIS LID EVOLVES OVER THE NIGHT...BUT
WE WILL AT LEAST BE TRENDING TOWARD MORE UNSTABLE CONDITIONS. SOME
SHORTWAVE ENERGY/VORTICITY EJECTS FROM AFOREMENTIONED CLOSED LOW
DRIFTING THROUGH SRN CANADA. THIS FORCING ARRIVES LATE EVENING AND
OVERNIGHT. WEAK LOW PRESSURE AND A WARM FRONT LIFT UP TOWARD/INTO
NRN MICHIGAN. THE SAME FCST BFR SOUNDINGS...IN A SCENARIO LIKE
THIS...WOULD LIKELY ERODE/SUPPRESS THE CAP...UNLIKE THE GFS
SUGGESTION. RATHER...WILL GO WITH SHOWERS AND EMBEDDED
GARDEN-VARIETY THUNDERSTORMS DEVELOPING LATE EVENING/OVERNIGHT.
NOTHING SEVERE ANTICIPATED...AS OUR LAPSE RATES AND OVERALL
INSTABILITY WILL NOT MIRROR CURRENT ENVIRONMENT ACROSS THE NRN
PLAINS. WE WILL ONLY HAVE SEVERAL HUNDRED J/KG MUCAPE WITH LAPSE
RATES ALOFT 6-6.5C/KM. THE GREATEST MUCAPE LIKELY TO BE DOWN AROUND
THE MANISTEE/CADILLAC AREAS...ALSO WHERE SOME ADDITIONAL LIFT
ASSISTANCE WILL BE PROVIDED BY UPPER DIVERGENCE IN SOMEWHAT OF A
DOUBLE JET STRUCTURE. WOULD GO WITH LIKELY CHANCES FOR SEEING
PRECIPITATION...BUT BULK OF INSTABILITY AND LLJ FORCING WILL ONCE
AGAIN BE ACROSS SRN WI/NRN IL/SRN LAKE MICHIGAN. THIS COULD BLOCK US
FROM SEEING SOME OF THE ACTION. REGARDLESS...LIKELY TO BE SOME
PRECIPITATION...BEST DESCRIPTION OF WHICH CAN BE PROVIDED BY LATER
SHIFTS AS THE EVENT UNFOLDS.
LOWS TONIGHT WILL LIKELY BE MILD WITH THICKENING CLOUDS...LOWER HALF
OF THE 60S MOST AREAS.
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 303 AM EDT FRI JUL 25 2014
...RAINY END TO THE WEEKEND/COOL TEMPERATURES ON THE WAY FOR THE
START OF NEXT WEEK...
HIGH IMPACT WEATHER POTENTIAL: NOT A BUNCH. CHANCES FOR A FEW
NON-SEVERE THUNDERSTORMS HEADING THROUGH THE WEEKEND.
PATTERN SYNOPSIS/ANTICIPATED EVOLUTION: WHILE STILL PLENTY OF THE
FINER DETAILS TO WORK OUT...MUCH TALKED ABOUT TRANSITION TO A MORE
MERIDIONAL NOAM UPPER FLOW PATTERN STILL ON TARGET TO DEVELOP HEADING
INTO AND THROUGH NEXT WEEK. NO LINGERING DOUBT MICHIGAN WILL BE
CENTERED IN UNSEASONABLY CHILL PRODUCING TROUGH AXIS...WHICH WILL BE
A SLOW ONE TO DEPART ONCE IT DEVELOPS. PLAYERS FOR SUCH UNUSUAL
DEVELOPMENTS ALREADY ON THE TABLE...WITH LARGE NORTHERN QUEBEC GYRE
SIMPLY STUCK IN PLACE...ALL THE WHILE STRONG PACIFIC SHORTWAVE MAKES
STEADY EAST PROGRESS ACROSS THE SOUTHERN CANADIAN ROCKIES. THE
LATTER WILL SIMPLY REINFORCE AND EXTEND THE FORMER AS IT
SLING-SHOTS AROUND IT THROUGH EARLY NEXT WEEK. COMBINE THAT WITH
DEVELOPMENT OF FULLY MATURE GULF OF ALASKA TROUGH/WEST NOAM RIDGE
COUPLET (NOT TO MENTION ONE REALLY AMPLIFIED ATLANTIC RIDGE)...AND
ONE CAN SEE WHY A PATTERN MUCH MORE RESEMBLING THE COOL SEASON IS
EXPECTED.
PRIMARY FORECAST CONCERNS/CHALLENGES: TEMPERATURE TRENDS THROUGHOUT
AND EVOLUTION OF PERIODIC RAIN CHANCES. THUNDERSTORM POTENTIAL AND
INTENSITY WILL ALSO NEED ADDRESSING THIS WEEKEND.
DETAILS: SATURDAY CONTINUES TO REMAIN A CHALLENGE...WITH TIGHT
THETA-E GRADIENT AND SURGE OF BEST UPPER JET FORCING EXITING STAGE
RIGHT RATHER QUICKLY DURING THE MORNING. LEFT BEHIND WILL BE A MUCH
MORE MOIST LOW LEVEL AIRMASS...WITH DEWPOINTS EXPECTED TO BE UP IN
THE MID AND PERHAPS UPPER 60S. KINDA EXPECT WHAT EVER PUNCHES
THROUGH HERE TONIGHT WILL LARGELY EXIT DURING THE MORNING
HOURS...LEAVING NEXT LOW AMP WAVE AND DIURNAL DRIVEN DESTABILIZATION
TO DRIVE ADDITIONAL SHOWER AND STORM DEVELOPMENT. MOISTURE CROSS
SECTIONS SHOW GOOD TO EXCELLENT MOISTURE DEPTH UP THROUGH H7...WITH
AGGRESSIVE DRYING ABOVE THIS LAYER. MANIPULATING MODEL DERIVED
SOUNDINGS WITH ANTICIPATED DEWPOINTS/TEMPERATURES DOES YIELD
DEVELOPMENT OF UPWARDS OF 1K-1.5K J/KG OF ML CAPE DURING THE
AFTERNOON. THINK THIS MIGHT BE A TOUCH AGGRESSIVE...EXPECTING LOW
LEVELS TO BE NOT QUITE AS SATURATED AS GUIDANCE WOULD SUGGEST. WHILE
BEST DYNAMICS WILL HAVE EXITED...NOT ALL IS LOST...WITH MID LEVEL
JET ROTATING THROUGH THE SOUTHWEST LAKES...COMBINING WITH LAKE
INDUCED LOW LEVEL CONVERGENCE /PARTICULARLY IN NORTHEAST LOWER AND
INTERIOR EASTERN UPPER MICHIGAN/ AND SAID WEAK WAVE. ABOVE
DEFINITELY SUPPORTS SOME ADDITIONAL CONVECTIVE POTENTIAL...
ESPECIALLY IN CLIMATOLOGICALLY FAVORED AREAS. INHERITED FORECAST
ALREADY WELL TRENDED IN THIS DIRECTION...WITH ONLY SOME MASSAGING
NEEDED TO POP/WEATHER GRID. DECENT DEEP LAYER SHEAR OF 30 TO 40
KNOTS LARGELY OFFSET BY LIMITED MID LEVEL LAPSE RATES AND SKINNY
CAPE PROFILE UP THROUGH HAIL GROWTH ZONE. SO...IF STORMS CAN DEVELOP
(A BIG IF)...WOULD EXPECT THEM TO REMAIN BELOW SEVERE LIMITS.
LOSS OF INSTABILITY AND RAPID APPROACH OF SHORTWAVE RIDGING EXPECTED
TO BRING A MOSTLY DRY SATURDAY NIGHT. RATHER VIGOROUS CURRENT
SOUTHERN CANADA WAVE QUICKLY FOLLOWS FOR SUNDAY...AND WHEN COMBINED
WITH GOOD SLUG OF LEFT EXIT REGION UPPER JET DYNAMICS...LOOKS TO
BRING A RATHER WIDESPREAD SHOWER EVENT SUNDAY INTO SUNDAY NIGHT.
SYSTEM EVEN LOOKS TO TAKE ON COLD SEASON CHARACTERISTICS...WITH MORE
STEADY RAIN POTENTIAL IN FAVORED NORTH SIDE DEFORMATION FIELD. SOME
THUNDER THREAT REMAINS SUNDAY WITH OPPORTUNITY FOR SOME
DESTABILIZATION BEFORE BETTER FORCING ARRIVES.
TROUGHING DIGS IN AND STAYS THERE-ON-AFTER...PERHAPS LASTING THROUGH
ALL OF NEXT WEEK. COLDEST ANOMALIES EXPECTED TO SLIDE JUST OFF TO
OUR NORTHEAST. THAT SAID...COLD AIR ADVECTION ON FRONTSIDE OF
SPRAWLING NORTHERN PLAINS HIGH WILL BE IMPRESSIVE INDEED...ONCE
AGAIN NOT ALLOWING TEMPERATURES TO GET OUT OF THE 60S ON MONDAY. A
VERY SLOW MODERATION TO FOLLOW...WITH HIGHS WARMING A FEW DEGREES
EACH DAY THROUGH THURSDAY (EVEN BY THURSDAY...HIGHS WILL STILL BE A
FEW DEGREES BELOW NORMAL). DESPITE TROUGHING...JUST NOT OVERLY
IMPRESSED WITH RAIN CHANCES AFTER SUNDAY NIGHTS WAVE PASSAGE. DEEP
LAYER FLOW WILL REMAIN NORTH TO NORTHWEST...AND MID LEVEL
TEMPERATURE REALLY NEVER GET TOO COLD...REACHING THE NEGATIVE UPPER
TEENS AT H5 LATER MONDAY INTO TUESDAY. OF COURSE...ANY WAVES
ROTATING THROUGH WILL ONLY HELP THE SHOWER CAUSE...BUT TIMING AND
MAGNITUDE OF SUCH NOT POSSIBLE TO DETERMINE JUST YET. NO REASON TO
CHANGE THAT WHICH WAS INHERITED...FEATURING JUST ISOLATED/LOW CHANCE
SHOWER POTENTIAL DURING THE DAYTIME HOURS. THIS WILL CHANGE...OF
COURSE...BUT PLENTY OF TIME TO FIGURE THOSE DETAILS OUT IN THE
COMING DAYS.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SATURDAY MORNING)
ISSUED AT 609 AM EDT FRI JUL 25 2014
...MAINLY VFR WITH CHANCES FOR SHOWERS AND STORMS TONIGHT...
SFC HIGH PRESSURE HAS EXITED SOUTHEAST ALLOWING FOR A LIGHT SW
RETURN FLOW. THIS GRADIENT TIGHTENS A TOUCH TODAY WITH GUSTS UP TO
15-18KTS EXPECTED...MAINLY ACROSS NW LOWER. CUMULUS AND SOME
HIGHER CLOUD EXPECTED TO ROLL ON THROUGH TODAY AND POSSIBLY GET
STUCK UNDERNEATH AN INVERSION FOR A PERIOD OF MORE CLOUDY
CONDITIONS. WEAK LOW PRESSURE AND A WARM FRONT ARRIVE TONIGHT WITH
THE CHANCE FOR SHOWERS AND STORMS AHEAD OF IT. EXACT EVOLUTION OF
THE PRECIPITATION NEBULOUS RIGHT NOW...WILL INCLUDE A VCSH FOR THE
NIGHT.
NO SEVERE WEATHER ANTICIPATED. BRIEF HEAVY RAIN AND LIGHTNING
HOWEVER.
&&
.MARINE...
ISSUED AT 303 AM EDT FRI JUL 25 2014
SW WINDS WILL INCREASE HEADING THROUGH TONIGHT...AHEAD OF SFC LOW
PRESSURE AND A WARM FRONT...WHICH WILL BRING AREAS OF SHOWERS AND
GARDEN-VARIETY STORMS TO THE GREAT LAKES. NOTHING SEVERE....AND
WINDS TO REMAIN ABOVE ADVISORY LEVELS. EXPECTING NO MORE THAN
20KTS..WHICH WILL LARGELY RESIDE ACROSS LAKE MICHIGAN. WINDS REMAIN
UNDER ADVISORY LEVELS SATURDAY AND SUNDAY IN WEAK GRADIENT. ANOTHER
SFC LOW CROSSES SUNDAY MORNING WITH A BETTER CHANCE FOR SHOWERS AND
STORMS...AND MUCH COOLER AIR SET TO ARRIVE THROUGH THE DAY SUNDAY
AND SUNDAY NIGHT.
&&
.APX WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LH...NONE.
LM...NONE.
LS...NONE.
&&
$$
SYNOPSIS...MSB
SHORT TERM...SMD
LONG TERM...MSB
AVIATION...SMD
MARINE...SMD
AREA FORECAST DISCUSSION
NWS GAYLORD MI
305 AM EDT FRI JUL 25 2014
.SYNOPSIS...
ISSUED AT 303 AM EDT FRI JUL 25 2014
HIGH PRESSURE WILL GIVE WAY TO A FAST MOVING SYSTEM TONIGHT AND
SATURDAY. CLOUDS WILL BE ON THE INCREASE TODAY...WITH A CHANCE FOR
SHOWERS AND A FEW THUNDERSTORMS TONIGHT INTO THE START OF THE
WEEKEND. A MUCH STRONGER SYSTEM WILL ARRIVE TO END THE WEEKEND...
BRINGING BETTER POTENTIAL FOR SHOWERS SUNDAY AND SUNDAY NIGHT. A
RETURN TO MUCH BELOW NORMAL TEMPERATURES ON MONDAY...WITH ONLY A
SLOW MODERATION EXPECTED THROUGH THE REMAINDER OF THE WEEK.
&&
.SHORT TERM...(TODAY THROUGH TONIGHT)
ISSUED AT 303 AM EDT FRI JUL 25 2014
...MORE CLOUDS AND A SHADE WARMER WITH STORM CHANCES TONIGHT...
IMPACTS: LIGHTNING...BUT NO SEVERE WEATHER EXPECTED.
CURRENT WEATHER AND SYNOPTIC PATTERN:
BROAD UPPER RIDGING SEEN OVER THE SW PART OF THE COUNTRY WHILE
TROUGHING IS STILL THE THEME OVER THE EASTERN CONUS. THE RIDGING HAS
BEEN SQUASHED DUE TO A WRAPPED UP CLOSED LOW DRIFTS ACROSS SW
CANADA. THIS HAS INDUCED LOW PRESSURE OVER EASTERN CANADA AND THE
NRN PLAINS. AN AXIS OF DEEP THETA-E AIR...LEADING EDGE OF STEEP
LAPSE RATES ALOFT (6.5C/KM-7.5C/KM) AND LLJ (45-55KT) CONVERGENCE
AHEAD OF THE PLAINS SFC LOW HAS RESULTED IN POCKETS OF SHOWERS AND
STORMS IN THE DAKOTAS DOWN TO NE. CLOSER TO HOME...AREA VAD WIND
PROFILES AND RUC ANALYSIS SHOWING A TROUGH AXIS AND H8 MOISTURE
ADVECTION FROM THE ARROWHEAD OF MN DOWN THROUGH WISCONSIN. THERE
WERE A FEW ELEVATED RETURNS...BUT ONLY A FEW SPRINKLES HITTING
GROUND PER AREA OBS. OVER NRN MICHIGAN...WE ARE STILL UNDER THE
INFLUENCE OF SFC HIGH PRESSURE...BUT THOSE SAME VAD WIND PROFILES
SHOW THAT THIS HAS SHIFTED JUST EAST OF US WITH A RETURN TO A SW
WIND. AIR MASS IS STILL QUITE DRY WITH PWATS RELATIVELY LOWER THAN
ANYWHERE NEARBY. ONLY A BAND OF HIGHER LEVEL CLOUD STREAMING DOWN
THROUGH THE NW FLOW ALOFT. THE DRY AIR AND MOSTLY CLEAR SKIES HAVE
ALLOWED TEMPERATURES TO FALL INTO THE LOWER HALF OF THE 40S IN THE
LOW LYING AREAS...WHILE COASTAL AREAS AND SOME EXPOSED HIGHER
TERRAIN ARE IN THE LOWER HALF OF THE 50S.
SYNOPTIC PATTERN/WEATHER EVOLUTION:
THE SFC HIGH GRADUALLY SINKS OFF TO THE SE TODAY...WHILE THE
SOUTHERLY PRESSURE GRADIENT TIGHTENS AND DRAWS IN MORE LOW LEVEL
MOISTURE THROUGH THE DAY AND NIGHT. THE INITIAL H8 TROUGH AND
MOISTURE ADVECTION WILL DRIFT OVERHEAD TODAY...AND MAYBE SOME
SPRINKLES ARE POSSIBLE EARLY THIS MORNING...BUT DAYTIME MIXING AND
DRYING OF THE LOWER LEVELS WILL MOST LIKELY SEAL OFF ANY CHANCES FOR
SPRINKLES TO HIT GROUND. THE MOISTURE WILL REVEAL ITSELF IN A HIGHER
BASED CUMULUS FIELD...BUT ALSO MAY GET STUCK UNDERNEATH AN INVERSION
IN FCST BFR SOUNDINGS. THIS COULD LEAD TO A PERIOD OF MOSTLY CLOUDY
SKIES...BUT REALLY DOUBT THIS WILL HAVE MUCH AFFECT ON RISING TEMPS
REACHING THE MIDDLE 70S MOST AREAS. THIS INVERSION AND DRY SFC TDS
RESULT IN A PRETTY PRONOUNCED CAPPING FOR THE ENTIRE DAY...WITH
LITTLE TO NO CHANCE FOR AFTERNOON CONVECTION.
THERE ARE DIFFERENCES IN HOW THIS LID EVOLVES OVER THE NIGHT...BUT
WE WILL AT LEAST BE TRENDING TOWARD MORE UNSTABLE CONDITIONS. SOME
SHORTWAVE ENERGY/VORTICITY EJECTS FROM AFOREMENTIONED CLOSED LOW
DRIFTING THROUGH SRN CANADA. THIS FORCING ARRIVES LATE EVENING AND
OVERNIGHT. WEAK LOW PRESSURE AND A WARM FRONT LIFT UP TOWARD/INTO
NRN MICHIGAN. THE SAME FCST BFR SOUNDINGS...IN A SCENARIO LIKE
THIS...WOULD LIKELY ERODE/SUPPRESS THE CAP...UNLIKE THE GFS
SUGGESTION. RATHER...WILL GO WITH SHOWERS AND EMBEDDED
GARDEN-VARIETY THUNDERSTORMS DEVELOPING LATE EVENING/OVERNIGHT.
NOTHING SEVERE ANTICIPATED...AS OUR LAPSE RATES AND OVERALL
INSTABILITY WILL NOT MIRROR CURRENT ENVIRONMENT ACROSS THE NRN
PLAINS. WE WILL ONLY HAVE SEVERAL HUNDRED J/KG MUCAPE WITH LAPSE
RATES ALOFT 6-6.5C/KM. THE GREATEST MUCAPE LIKELY TO BE DOWN AROUND
THE MANISTEE/CADILLAC AREAS...ALSO WHERE SOME ADDITIONAL LIFT
ASSISTANCE WILL BE PROVIDED BY UPPER DIVERGENCE IN SOMEWHAT OF A
DOUBLE JET STRUCTURE. WOULD GO WITH LIKELY CHANCES FOR SEEING
PRECIPITATION...BUT BULK OF INSTABILITY AND LLJ FORCING WILL ONCE
AGAIN BE ACROSS SRN WI/NRN IL/SRN LAKE MICHIGAN. THIS COULD BLOCK US
FROM SEEING SOME OF THE ACTION. REGARDLESS...LIKELY TO BE SOME
PRECIPITATION...BEST DESCRIPTION OF WHICH CAN BE PROVIDED BY LATER
SHIFTS AS THE EVENT UNFOLDS.
LOWS TONIGHT WILL LIKELY BE MILD WITH THICKENING CLOUDS...LOWER HALF
OF THE 60S MOST AREAS.
&&
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 303 AM EDT FRI JUL 25 2014
...RAINY END TO THE WEEKEND/COOL TEMPERATURES ON THE WAY FOR THE
START OF NEXT WEEK...
HIGH IMPACT WEATHER POTENTIAL: NOT A BUNCH. CHANCES FOR A FEW
NON-SEVERE THUNDERSTORMS HEADING THROUGH THE WEEKEND.
PATTERN SYNOPSIS/ANTICIPATED EVOLUTION: WHILE STILL PLENTY OF THE
FINER DETAILS TO WORK OUT...MUCH TALKED ABOUT TRANSITION TO A MORE
MERIDIONAL NOAM UPPER FLOW PATTERN STILL ON TARGET TO DEVELOP HEADING
INTO AND THROUGH NEXT WEEK. NO LINGERING DOUBT MICHIGAN WILL BE
CENTERED IN UNSEASONABLY CHILL PRODUCING TROUGH AXIS...WHICH WILL BE
A SLOW ONE TO DEPART ONCE IT DEVELOPS. PLAYERS FOR SUCH UNUSUAL
DEVELOPMENTS ALREADY ON THE TABLE...WITH LARGE NORTHERN QUEBEC GYRE
SIMPLY STUCK IN PLACE...ALL THE WHILE STRONG PACIFIC SHORTWAVE MAKES
STEADY EAST PROGRESS ACROSS THE SOUTHERN CANADIAN ROCKIES. THE
LATTER WILL SIMPLY REINFORCE AND EXTEND THE FORMER AS IT
SLING-SHOTS AROUND IT THROUGH EARLY NEXT WEEK. COMBINE THAT WITH
DEVELOPMENT OF FULLY MATURE GULF OF ALASKA TROUGH/WEST NOAM RIDGE
COUPLET (NOT TO MENTION ONE REALLY AMPLIFIED ATLANTIC RIDGE)...AND
ONE CAN SEE WHY A PATTERN MUCH MORE RESEMBLING THE COOL SEASON IS
EXPECTED.
PRIMARY FORECAST CONCERNS/CHALLENGES: TEMPERATURE TRENDS THROUGHOUT
AND EVOLUTION OF PERIODIC RAIN CHANCES. THUNDERSTORM POTENTIAL AND
INTENSITY WILL ALSO NEED ADDRESSING THIS WEEKEND.
DETAILS: SATURDAY CONTINUES TO REMAIN A CHALLENGE...WITH TIGHT
THETA-E GRADIENT AND SURGE OF BEST UPPER JET FORCING EXITING STAGE
RIGHT RATHER QUICKLY DURING THE MORNING. LEFT BEHIND WILL BE A MUCH
MORE MOIST LOW LEVEL AIRMASS...WITH DEWPOINTS EXPECTED TO BE UP IN
THE MID AND PERHAPS UPPER 60S. KINDA EXPECT WHAT EVER PUNCHES
THROUGH HERE TONIGHT WILL LARGELY EXIT DURING THE MORNING
HOURS...LEAVING NEXT LOW AMP WAVE AND DIURNAL DRIVEN DESTABILIZATION
TO DRIVE ADDITIONAL SHOWER AND STORM DEVELOPMENT. MOISTURE CROSS
SECTIONS SHOW GOOD TO EXCELLENT MOISTURE DEPTH UP THROUGH H7...WITH
AGGRESSIVE DRYING ABOVE THIS LAYER. MANIPULATING MODEL DERIVED
SOUNDINGS WITH ANTICIPATED DEWPOINTS/TEMPERATURES DOES YIELD
DEVELOPMENT OF UPWARDS OF 1K-1.5K J/KG OF ML CAPE DURING THE
AFTERNOON. THINK THIS MIGHT BE A TOUCH AGGRESSIVE...EXPECTING LOW
LEVELS TO BE NOT QUITE AS SATURATED AS GUIDANCE WOULD SUGGEST. WHILE
BEST DYNAMICS WILL HAVE EXITED...NOT ALL IS LOST...WITH MID LEVEL
JET ROTATING THROUGH THE SOUTHWEST LAKES...COMBINING WITH LAKE
INDUCED LOW LEVEL CONVERGENCE /PARTICULARLY IN NORTHEAST LOWER AND
INTERIOR EASTERN UPPER MICHIGAN/ AND SAID WEAK WAVE. ABOVE
DEFINITELY SUPPORTS SOME ADDITIONAL CONVECTIVE POTENTIAL...
ESPECIALLY IN CLIMATOLOGICALLY FAVORED AREAS. INHERITED FORECAST
ALREADY WELL TRENDED IN THIS DIRECTION...WITH ONLY SOME MASSAGING
NEEDED TO POP/WEATHER GRID. DECENT DEEP LAYER SHEAR OF 30 TO 40
KNOTS LARGELY OFFSET BY LIMITED MID LEVEL LAPSE RATES AND SKINNY
CAPE PROFILE UP THROUGH HAIL GROWTH ZONE. SO...IF STORMS CAN DEVELOP
(A BIG IF)...WOULD EXPECT THEM TO REMAIN BELOW SEVERE LIMITS.
LOSS OF INSTABILITY AND RAPID APPROACH OF SHORTWAVE RIDGING EXPECTED
TO BRING A MOSTLY DRY SATURDAY NIGHT. RATHER VIGOROUS CURRENT
SOUTHERN CANADA WAVE QUICKLY FOLLOWS FOR SUNDAY...AND WHEN COMBINED
WITH GOOD SLUG OF LEFT EXIT REGION UPPER JET DYNAMICS...LOOKS TO
BRING A RATHER WIDESPREAD SHOWER EVENT SUNDAY INTO SUNDAY NIGHT.
SYSTEM EVEN LOOKS TO TAKE ON COLD SEASON CHARACTERISTICS...WITH MORE
STEADY RAIN POTENTIAL IN FAVORED NORTH SIDE DEFORMATION FIELD. SOME
THUNDER THREAT REMAINS SUNDAY WITH OPPORTUNITY FOR SOME
DESTABILIZATION BEFORE BETTER FORCING ARRIVES.
TROUGHING DIGS IN AND STAYS THERE-ON-AFTER...PERHAPS LASTING THROUGH
ALL OF NEXT WEEK. COLDEST ANOMALIES EXPECTED TO SLIDE JUST OFF TO
OUR NORTHEAST. THAT SAID...COLD AIR ADVECTION ON FRONTSIDE OF
SPRAWLING NORTHERN PLAINS HIGH WILL BE IMPRESSIVE INDEED...ONCE
AGAIN NOT ALLOWING TEMPERATURES TO GET OUT OF THE 60S ON MONDAY. A
VERY SLOW MODERATION TO FOLLOW...WITH HIGHS WARMING A FEW DEGREES
EACH DAY THROUGH THURSDAY (EVEN BY THURSDAY...HIGHS WILL STILL BE A
FEW DEGREES BELOW NORMAL). DESPITE TROUGHING...JUST NOT OVERLY
IMPRESSED WITH RAIN CHANCES AFTER SUNDAY NIGHTS WAVE PASSAGE. DEEP
LAYER FLOW WILL REMAIN NORTH TO NORTHWEST...AND MID LEVEL
TEMPERATURE REALLY NEVER GET TOO COLD...REACHING THE NEGATIVE UPPER
TEENS AT H5 LATER MONDAY INTO TUESDAY. OF COURSE...ANY WAVES
ROTATING THROUGH WILL ONLY HELP THE SHOWER CAUSE...BUT TIMING AND
MAGNITUDE OF SUCH NOT POSSIBLE TO DETERMINE JUST YET. NO REASON TO
CHANGE THAT WHICH WAS INHERITED...FEATURING JUST ISOLATED/LOW CHANCE
SHOWER POTENTIAL DURING THE DAYTIME HOURS. THIS WILL CHANGE...OF
COURSE...BUT PLENTY OF TIME TO FIGURE THOSE DETAILS OUT IN THE
COMING DAYS.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z FRIDAY NIGHT)
ISSUED AT 136 AM EDT FRI JUL 25 2014
VFR CONDITIONS ARE EXPECTED AT ALL NRN LWR MICHIGAN TAF SITES THRU
FRIDAY NIGHT. SCT CU AND INCREASING MID CLOUDS ON FRIDAY WILL LEND
TO PARTLY TO MOSTLY CLOUDY SKIES. CHANCES OF SHOWERS AND
THUNDERSTORMS WILL BEGIN TO INCREASE AFTER 00Z SATURDAY AHEAD OF A
WEAK COOL FRONT...BUT CHANCES ARE TOO SMALL TO INCLUDE IN THE TAF AT
THIS POINT. LIGHT/VARIABLE WINDS OVERNIGHT INTO THE MORNING HOURS
WILL BECOME S/SW AT AROUND 10 KTS BY LATE MORNING.
&&
.MARINE...
ISSUED AT 303 AM EDT FRI JUL 25 2014
SW WINDS WILL INCREASE HEADING THROUGH TONIGHT...AHEAD OF SFC LOW
PRESSURE AND A WARM FRONT...WHICH WILL BRING AREAS OF SHOWERS AND
GARDEN-VARIETY STORMS TO THE GREAT LAKES. NOTHING SEVERE....AND
WINDS TO REMAIN ABOVE ADVISORY LEVELS. EXPECTING NO MORE THAN
20KTS..WHICH WILL LARGELY RESIDE ACROSS LAKE MICHIGAN. WINDS REMAIN
UNDER ADVISORY LEVELS SATURDAY AND SUNDAY IN WEAK GRADIENT. ANOTHER
SFC LOW CROSSES SUNDAY MORNING WITH A BETTER CHANCE FOR SHOWERS AND
STORMS...AND MUCH COOLER AIR SET TO ARRIVE THROUGH THE DAY SUNDAY
AND SUNDAY NIGHT.
&&
.APX WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LH...NONE.
LM...NONE.
LS...NONE.
&&
$$
SYNOPSIS...MSB
SHORT TERM...SMD
LONG TERM...MSB
AVIATION...MR
MARINE...SMD
AREA FORECAST DISCUSSION
NWS TWIN CITIES/CHANHASSEN MN
1214 PM CDT FRI JUL 25 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 330 AM CDT FRI JUL 25 2014
EARLY MORNING THUNDERSTORMS CONTINUED TO DEVELOP ACROSS THE REGION
THIS MORNING FUELED BY THE VEERING WINDS ASSOCIATED WITH THE THETA_E
ADVECTION IN CONNECTION WITH THE LOW LEVEL JET. OVER THE NEXT FEW
HOURS THIS 40KT JET WILL BECOME MORE FOCUSED ACROSS SOUTHERN...AND
EVENTUALLY SOUTHEASTERN MN. AS A RESULT PRECIPITATION WILL CONTINUE
TO DEVELOP FOR THE NEXT FEW HOURS...BUT SHOULD GRADUALLY WANE
SHORTLY AFTER SUNSET AS IT ENTERS WESTERN WI.
EARLIER RUNS OF THE RAP MISSED THE PRECIP THAT DEVELOPED IN
NORTHEAST SD...SO IT IS NO SURPRISE THAT HIGHRES MODELS HAVE BEEN
STRUGGLING TO GET A HANDLE ON THE TWO AREAS OF PRECIP THAT DEVELOPED
EARLIER. AS A RESULT MOST OF THE RUNS HAVE BEEN ALL BUT DISCARDED.
THE 25.06HRRR HAS FINALLY CAUGHT UP AND IT SUPPORTS THE IDEA OF
CONTINUED CONVECTION THIS MORNING...BUT WITH A WEAKENING TREND AFTER
11Z. THE SEVERE WEATHER THREAT IS VERY LOW GIVEN THE DEEP STABLE
LAYER BENEATH THE ELEVATED CAPE...AND ONLY MARGINAL 30-35KTS OF
EFFECTIVE SHEAR.
LOOKING AHEAD...SKIES SHOULD CLEAR BEHIND THE MORNING PRECIP
YIELDING ANOTHER MUGGY AFTERNOON AS DEWPOINTS CLIMB BACK TO NEAR
70F. INCREASED TEMPS SLIGHTLY ACROSS WEST OF I35...AND RAISED
DEWPOINTS AS WELL. OVERNIGHT NORTHWESTERLY WINDS WILL PUSH A COLD
FRONT THROUGH THE REGION SENDING DEWPOINTS BACK INTO THE UPPER 50S
BY SATURDAY MORNING.
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 330 AM CDT FRI JUL 25 2014
THE WEEKEND STARTS OUT ON A MILD NOTE...AS THE AREA REMAINS
SANDWICHED BETWEEN A SOUTHERN CONUS RIDGE TO THE SOUTH...AND A
MID LEVEL LOW TO THE NORTH IN SASKATCHEWAN/MANITOBA. THE RESULT WILL
BE SLIGHTLY WARMER THAN NORMAL HIGHS IN THE MID 80S ON
SATURDAY...FOLLOWED BY INCREASING PRECIPITATION CHANCES INTO
SUNDAY AS THE AFOREMENTIONED LOW DROPS SOUTH-SOUTHEAST FROM
SOUTHERN MANITOBA. AS IS COMMON WITH THESE TYPES OF
LOWS...PRECIPITATION CHANCES APPEAR THE HIGHEST FROM CENTRAL MN
INTO WI...WHERE FORCING/MOISTURE IS DEEPER. EXPECT SHOWERS WITH
ISOLATED THUNDERSTORMS ON SUNDAY...PARTICULARLY DURING THE AFTERNOON
HOURS AS DIURNAL HEATING AIDS DESTABILIZATION.
NEXT WEEK STARTS OUT ON A DRY AND MILD NOTE AS THE WEEKEND LOW
SHIFTS SOUTHEAST AND A BROAD SURFACE RIDGE BUILDS ACROSS THE
CENTRAL CONUS. THE LOCAL AREA REMAINS CRAMMED BETWEEN WESTERN
RIDGING AND EASTERN TROUGHING AT THE MID TO UPPER LEVELS OF THE
ATMOSPHERE...YIELDING COOLER THAN NORMAL HIGHS FROM MONDAY THROUGH
WEDNESDAY MOSTLY IN THE 70S...AND LOWS IN THE 50S.
THURSDAY AND FRIDAY BRING THE NEXT CHANCE FOR MEASURABLE
PRECIPITATION AS SHORTWAVE ENERGY BEGINS TO TRICKLE SOUTH ON THE
WESTERN PERIPHERY OF THE EASTERN CONUS TROUGH. CHANCES ARE NOT
HIGH AT THIS POINT GIVEN MODEST FORCING AND MOISTURE...BUT
SUFFICIENT FOR THE INCLUSION OF 20-30 POPS.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON)
ISSUED AT 1205 PM CDT FRI JUL 25 2014
ABUNDANT LOW LEVEL MOSITURE AHEAD OF INCOMING FRONT/TROUGH WILL
CONTINUE BKN MVFR CIGS FOR A COUPLE HOURS OR SO. THEN VFR OVER MN
PORTION OF THE CWA THROUGH THE REMAINDER OF THE PERIOD. SOME
THREAT OF FOG DEVELOPING AHEAD OF WEAK BOUNDARY IF THE SKY CLEARS
TO THE EAST. WILL CONTINUE TO MENTION THAT POTENTIAL AT KSTC-KRNH-
KEAU REGION. SOME THREAT OF THUNDER ALONG BOUNDARY AS WELL...BUT
WOULD BE ISOLD IF IT DID OCCUR. SFC HEATING LIMITED WITH CLOUDS TO
THE EAST AND MID LEVEL CAP IS EXPECTED TO HOLD. SOUTH/SOUTHWEST
WINDS BECOMING WEST/NW WITH FROPA...MAINLY WEST AS FRONT MOVES
EAST AND WEAKENS.
KMSP...
CIGS EXPECTED TO LIFT TO VFR THROUGH 19Z-20Z. THEN BECOMING SCT BY
EVENING WITH SOME MID/HIGH LEVEL CLOUDS INTO SATURDAY. FOG
POTENTIAL WILL BE LIMITED AS WEAK TROUGH EXPECTED TO MOVE THROUGH
THIS EVENING. SOUTHWEST TO WEST WINDS EXPECTED GENERALLY LESS THAN
10KTS THROUGH THE PERIOD. SOME POTENTIAL OF SHRA/TSRA INTO SAT
EVENING. WILL ACCESS THIS FOR NEXT FCST ISSUANCE.
/OUTLOOK FOR KMSP/
SUN...VFR WITH MVFR/SHRA POSSIBLE. WINDS NW AT 10G15KTS.
MON...VFR. WINDS N AT 5KTS.
TUE...VFR. WINDS N AT 10KTS.
&&
.MPX WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...NONE.
&&
$$
SHORT TERM...JRB
LONG TERM...LS
AVIATION...DWE
AREA FORECAST DISCUSSION
NWS DULUTH MN
1149 AM CDT FRI JUL 25 2014
.UPDATE...
ISSUED AT 1146 AM CDT FRI JUL 25 2014
ISOLD TO WIDELY SCT SHOWERS ARE POPPING UP AND THEN DISSIPATING.
WITH THIS DIFFICULTY...HAVE A LOW POPS TO TRY AND ACCOUNT FOR THIS
ACTIVITY. STILL EXPECTING A FEW THUNDERSTORMS LATER THIS
AFTERNOON. REST OF THE FORECAST ON TRACK.
UPDATE ISSUED AT 903 AM CDT FRI JUL 25 2014
THE EARLY MORNING SHOWERS HAVE EXITED THE AREA. JUST A FEW
SPRINKLES REMAIN. HOWEVER...WITH THE UNSTABLE AIRMASS AND COLD
FRONT IN EASTERN ND...WAA/ISENTROPIC LIFT AHEAD OF SAID
FRONT...SHOWERS OR ISOLD THUNDERSTORMS MAY POP AT ANY TIME. HAVE
ADJUSTED POPS FOR THESE LATEST TRENDS.
UPDATE ISSUED AT 736 AM CDT FRI JUL 25 2014
UPDATED TO REFINE POPS AND REMOVE PRE-FIRST PERIOD BASED ON
CURRENT PRECIP AREA. THE SHOWERS AND THUNDERSTORMS SHOULD MOVE
SOUTH OUT OF THE FORECAST AREA BY 15Z. REST OF FCST UNCHANGED.
UPDATE ISSUED AT 430 AM CDT FRI JUL 25 2014
UPDATED TO INCREASE POPS ACROSS PORTIONS OF THE FORECAST AREA. AREA
OF SHOWERS AND THUNDERSTORMS MOVING ACROSS THOSE AREAS THIS
MORNING. THIS PRECIPITATION WILL END BY MID-MORNING. REST OF FCST UNCHANGED.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 242 AM CDT FRI JUL 25 2014
SHORT TERM CONCERN IS PRECIPITATION CHANCE TODAY AND TONIGHT.
CURRENT SURFACE ANALYSIS INDICATES RAIN SHOWERS NORTH OF THE IRON
RANGE AND IN THE ARROWHEAD. THESE SHOWERS ARE ASSOCIATED WITH A WEAK
SHORTWAVE MOVING THROUGH THE AREA. THEY WILL CONTINUE MOVE
SOUTHEAST AND SLOWLY DISSIPATE EARLY THIS MORNING. THERE IS AN
AREA OF THUNDERSTORMS ALONG THE ND/SD/WRN MN BORDER MOVING ESE.
THE AREA HAS DECREASED IN INTENSITY OVER THE PAST HOUR. THE
NORTHERN EDGE OF THE PRECIPITATION MAY CLIP CASS AND CROW WING
COUNTIES THIS MORNING. A WEAK SURFACE TROUGH WILL MOVE THROUGH MN
TODAY AND NW WI TONIGHT. IT WILL BRING ANOTHER ROUND OF SHOWERS
AND THUNDERSTORMS. THERE WILL BE SOME INCREASED INSTABILITY WITH
THE TROUGH THIS AFTERNOON AND EVENING. MUCAPES ARE
1500-2000...SHEAR IS 20-40...AND SOME SUN TODAY. SPC HAS THE
FORECAST AREA IN A 5% PROBABILITY FOR WIND/HAIL WITH THE MARGINAL
INSTABILITY.
AN AREA OF WEAK HIGH PRESSURE WILL BUILD INTO THE REGION FROM THE
WEST LATE THIS EVENING. THIS WILL END THE THREAT FOR PRECIPITATION
FOR LATE FRIDAY NIGHT AND SATURDAY. HOWEVER..BY THE AFTERNOON...AN
AREA OF LOW PRESSURE ALONG WITH A UPPER TROUGH WILL MOVE INTO
WESTERN MINNESOTA AND WILL EFFECT THE REGION SATURDAY NIGHT.
.LONG TERM...(SATURDAY NIGHT THROUGH THURSDAY)
ISSUED AT 242 AM CDT FRI JUL 25 2014
THE MODELS ARE IN PRETTY GOOD AGREEMENT THROUGH MUCH OF THE
PERIOD. AN UPPER TROUGH OVER SOUTHERN MANITOBA SATURDAY EVENING
WILL DROP INTO NORTHERN MINNESOTA BY 12Z SUN...THEN CONTINUE INTO
SOUTHERN WISCONSIN BY SUNDAY EVENING. A SURFACE LOW/TROUGH AXIS
WILL BE ASSOCIATED WITH THIS UPPER WAVE. SHOWERS AND A FEW
THUNDERSTORMS WILL INCREASE IN COVERAGE SATURDAY NIGHT INTO SUNDAY
MORNING...THEN DECREASE FROM NORTH TO SOUTH SUNDAY
AFTERNOON/EVENING. SUNDAY NIGHT SHOULD BE DRY. WE HAVE THE HIGHEST
POPS OVER THE EASTERN PORTION OF THE NORTHLAND LATE SATURDAY NIGHT
INTO SUNDAY MORNING.
HIGH PRESSURE WILL THEN LEAD TO MAINLY DRY CONDITIONS SUNDAY NIGHT
INTO MONDAY NIGHT. THERE MAY BE A FEW SHOWERS TUESDAY INTO WEDNESDAY
OVER THE EASTERN HALF OF THE NORTHLAND WITH A SERIES OF SHORTWAVES
MOVING THROUGH IN THE NORTHERLY FLOW ALOFT. WE ALSO HAVE A SMALL
CHANCE FOR SHOWERS/STORMS THURSDAY FOR MOST AREAS.
THE PERIOD WILL START OUT WITH BELOW NORMAL TEMPERATURES
SUNDAY...WITH HIGHS IN THE MID SIXTIES TO LOWER SEVENTIES.
TEMPERATURES WILL THEN MODERATE THROUGH THE REST OF THE
PERIOD...REACHING THE UPPER SEVENTIES TO LOWER EIGHTIES BY THURSDAY.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SATURDAY MORNING)
ISSUED AT 632 AM CDT FRI JUL 25 2014
SHOWERS AND A FEW THUNDERSTORMS WERE MOVING THROUGH
CENTRAL/EASTERN PORTIONS OF THE NORTHLAND EARLY THIS MORNING. WE
EXPECT A LULL IN COVERAGE TO DEVELOP THIS MORNING...THEN
ADDITIONAL DEVELOPMENT THIS AFTERNOON AHEAD OF THE SURFACE
BOUNDARY THAT WILL ONLY MOVE SLOWLY FROM WESTERN MINNESOTA EARLY
THIS AFTERNOON TOWARD THE EAST.
AN AREA OF MVFR/IFR CEILINGS HAVE DEVELOPED OVER WEST CENTRAL
MINNESOTA INTO CENTRAL MINNESOTA. THE RAP IS SUGGESTS THESE
CEILINGS WILL SPREAD NORTH AND EAST TODAY. HOWEVER...THE COVERAGE
CURRENTLY IS NOT AS GREAT AS THE RAP SUGGESTS. WE FEEL MOST
CONFIDENT KBRD WILL SEE THE LOWER CEILINGS AND ADDED A TEMPO GROUP
FOR THE REST OF THE TAF SITES BY MID TO LATE MORNING.
THE COVERAGE OF THE PRECIPITATION WILL DIMINISH THIS EVENING AND
SOME FOG WILL BE POSSIBLE.
&&
.PRELIMINARY POINT TEMPS/POPS...
DLH 75 59 82 59 / 50 30 50 50
INL 76 57 81 56 / 40 50 50 60
BRD 80 58 84 60 / 40 10 30 40
HYR 76 62 85 58 / 50 30 30 50
ASX 77 61 81 57 / 30 40 40 50
&&
.DLH WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...NONE.
LS...NONE.
&&
$$
UPDATE...GSF
SHORT TERM...STEWART
LONG TERM...MELDE
AVIATION...MELDE
AREA FORECAST DISCUSSION
NWS DULUTH MN
903 AM CDT FRI JUL 25 2014
.UPDATE...
ISSUED AT 903 AM CDT FRI JUL 25 2014
THE EARLY MORNING SHOWERS HAVE EXITED THE AREA. JUST A FEW
SPRINKLES REMAIN. HOWEVER...WITH THE UNSTABLE AIRMASS AND COLD
FRONT IN EASTERN ND...WAA/ISENTROPIC LIFT AHEAD OF SAID
FRONT...SHOWERS OR ISOLD THUNDERSTORMS MAY POP AT ANY TIME. HAVE
ADJUSTED POPS FOR THESE LATEST TRENDS.
UPDATE ISSUED AT 736 AM CDT FRI JUL 25 2014
UPDATED TO REFINE POPS AND REMOVE PRE-FIRST PERIOD BASED ON
CURRENT PRECIP AREA. THE SHOWERS AND THUNDERSTORMS SHOULD MOVE
SOUTH OUT OF THE FORECAST AREA BY 15Z. REST OF FCST UNCHANGED.
UPDATE ISSUED AT 430 AM CDT FRI JUL 25 2014
UPDATED TO INCREASE POPS ACROSS PORTIONS OF THE FORECAST AREA. AREA
OF SHOWERS AND THUNDERSTORMS MOVING ACROSS THOSE AREAS THIS
MORNING. THIS PRECIPITATION WILL END BY MID-MORNING. REST OF FCST UNCHANGED.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 242 AM CDT FRI JUL 25 2014
SHORT TERM CONCERN IS PRECIPITATION CHANCE TODAY AND TONIGHT.
CURRENT SURFACE ANALYSIS INDICATES RAIN SHOWERS NORTH OF THE IRON
RANGE AND IN THE ARROWHEAD. THESE SHOWERS ARE ASSOCIATED WITH A WEAK
SHORTWAVE MOVING THROUGH THE AREA. THEY WILL CONTINUE MOVE
SOUTHEAST AND SLOWLY DISSIPATE EARLY THIS MORNING. THERE IS AN
AREA OF THUNDERSTORMS ALONG THE ND/SD/WRN MN BORDER MOVING ESE.
THE AREA HAS DECREASED IN INTENSITY OVER THE PAST HOUR. THE
NORTHERN EDGE OF THE PRECIPITATION MAY CLIP CASS AND CROW WING
COUNTIES THIS MORNING. A WEAK SURFACE TROUGH WILL MOVE THROUGH MN
TODAY AND NW WI TONIGHT. IT WILL BRING ANOTHER ROUND OF SHOWERS
AND THUNDERSTORMS. THERE WILL BE SOME INCREASED INSTABILITY WITH
THE TROUGH THIS AFTERNOON AND EVENING. MUCAPES ARE
1500-2000...SHEAR IS 20-40...AND SOME SUN TODAY. SPC HAS THE
FORECAST AREA IN A 5% PROBABILITY FOR WIND/HAIL WITH THE MARGINAL
INSTABILITY.
AN AREA OF WEAK HIGH PRESSURE WILL BUILD INTO THE REGION FROM THE
WEST LATE THIS EVENING. THIS WILL END THE THREAT FOR PRECIPITATION
FOR LATE FRIDAY NIGHT AND SATURDAY. HOWEVER..BY THE AFTERNOON...AN
AREA OF LOW PRESSURE ALONG WITH A UPPER TROUGH WILL MOVE INTO
WESTERN MINNESOTA AND WILL EFFECT THE REGION SATURDAY NIGHT.
.LONG TERM...(SATURDAY NIGHT THROUGH THURSDAY)
ISSUED AT 242 AM CDT FRI JUL 25 2014
THE MODELS ARE IN PRETTY GOOD AGREEMENT THROUGH MUCH OF THE
PERIOD. AN UPPER TROUGH OVER SOUTHERN MANITOBA SATURDAY EVENING
WILL DROP INTO NORTHERN MINNESOTA BY 12Z SUN...THEN CONTINUE INTO
SOUTHERN WISCONSIN BY SUNDAY EVENING. A SURFACE LOW/TROUGH AXIS
WILL BE ASSOCIATED WITH THIS UPPER WAVE. SHOWERS AND A FEW
THUNDERSTORMS WILL INCREASE IN COVERAGE SATURDAY NIGHT INTO SUNDAY
MORNING...THEN DECREASE FROM NORTH TO SOUTH SUNDAY
AFTERNOON/EVENING. SUNDAY NIGHT SHOULD BE DRY. WE HAVE THE HIGHEST
POPS OVER THE EASTERN PORTION OF THE NORTHLAND LATE SATURDAY NIGHT
INTO SUNDAY MORNING.
HIGH PRESSURE WILL THEN LEAD TO MAINLY DRY CONDITIONS SUNDAY NIGHT
INTO MONDAY NIGHT. THERE MAY BE A FEW SHOWERS TUESDAY INTO WEDNESDAY
OVER THE EASTERN HALF OF THE NORTHLAND WITH A SERIES OF SHORTWAVES
MOVING THROUGH IN THE NORTHERLY FLOW ALOFT. WE ALSO HAVE A SMALL
CHANCE FOR SHOWERS/STORMS THURSDAY FOR MOST AREAS.
THE PERIOD WILL START OUT WITH BELOW NORMAL TEMPERATURES
SUNDAY...WITH HIGHS IN THE MID SIXTIES TO LOWER SEVENTIES.
TEMPERATURES WILL THEN MODERATE THROUGH THE REST OF THE
PERIOD...REACHING THE UPPER SEVENTIES TO LOWER EIGHTIES BY THURSDAY.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SATURDAY MORNING)
ISSUED AT 632 AM CDT FRI JUL 25 2014
SHOWERS AND A FEW THUNDERSTORMS WERE MOVING THROUGH
CENTRAL/EASTERN PORTIONS OF THE NORTHLAND EARLY THIS MORNING. WE
EXPECT A LULL IN COVERAGE TO DEVELOP THIS MORNING...THEN
ADDITIONAL DEVELOPMENT THIS AFTERNOON AHEAD OF THE SURFACE
BOUNDARY THAT WILL ONLY MOVE SLOWLY FROM WESTERN MINNESOTA EARLY
THIS AFTERNOON TOWARD THE EAST.
AN AREA OF MVFR/IFR CEILINGS HAVE DEVELOPED OVER WEST CENTRAL
MINNESOTA INTO CENTRAL MINNESOTA. THE RAP IS SUGGESTS THESE
CEILINGS WILL SPREAD NORTH AND EAST TODAY. HOWEVER...THE COVERAGE
CURRENTLY IS NOT AS GREAT AS THE RAP SUGGESTS. WE FEEL MOST
CONFIDENT KBRD WILL SEE THE LOWER CEILINGS AND ADDED A TEMPO GROUP
FOR THE REST OF THE TAF SITES BY MID TO LATE MORNING.
THE COVERAGE OF THE PRECIPITATION WILL DIMINISH THIS EVENING AND
SOME FOG WILL BE POSSIBLE.
&&
.PRELIMINARY POINT TEMPS/POPS...
DLH 75 59 82 59 / 50 30 50 50
INL 76 57 81 56 / 40 50 50 60
BRD 80 58 84 60 / 40 10 30 40
HYR 76 62 85 58 / 50 30 30 50
ASX 77 61 81 57 / 30 40 40 50
&&
.DLH WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...NONE.
LS...NONE.
&&
$$
UPDATE...GSF
SHORT TERM...STEWART
LONG TERM...MELDE
AVIATION...MELDE
AREA FORECAST DISCUSSION
NWS DULUTH MN
736 AM CDT FRI JUL 25 2014
.UPDATE...
ISSUED AT 736 AM CDT FRI JUL 25 2014
UPDATED TO REFINE POPS AND REMOVE PRE-FIRST PERIOD BASED ON
CURRENT PRECIP AREA. THE SHOWERS AND THUNDERSTORMS SHOULD MOVE
SOUTH OUT OF THE FORECAST AREA BY 15Z. REST OF FCST UNCHANGED.
UPDATE ISSUED AT 430 AM CDT FRI JUL 25 2014
UPDATED TO INCREASE POPS ACROSS PORTIONS OF THE FORECAST AREA. AREA
OF SHOWERS AND THUNDERSTORMS MOVING ACROSS THOSE AREAS THIS
MORNING. THIS PRECIPITATION WILL END BY MID-MORNING. REST OF FCST UNCHANGED.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 242 AM CDT FRI JUL 25 2014
SHORT TERM CONCERN IS PRECIPITATION CHANCE TODAY AND TONIGHT.
CURRENT SURFACE ANALYSIS INDICATES RAIN SHOWERS NORTH OF THE IRON
RANGE AND IN THE ARROWHEAD. THESE SHOWERS ARE ASSOCIATED WITH A WEAK
SHORTWAVE MOVING THROUGH THE AREA. THEY WILL CONTINUE MOVE
SOUTHEAST AND SLOWLY DISSIPATE EARLY THIS MORNING. THERE IS AN
AREA OF THUNDERSTORMS ALONG THE ND/SD/WRN MN BORDER MOVING ESE.
THE AREA HAS DECREASED IN INTENSITY OVER THE PAST HOUR. THE
NORTHERN EDGE OF THE PRECIPITATION MAY CLIP CASS AND CROW WING
COUNTIES THIS MORNING. A WEAK SURFACE TROUGH WILL MOVE THROUGH MN
TODAY AND NW WI TONIGHT. IT WILL BRING ANOTHER ROUND OF SHOWERS
AND THUNDERSTORMS. THERE WILL BE SOME INCREASED INSTABILITY WITH
THE TROUGH THIS AFTERNOON AND EVENING. MUCAPES ARE
1500-2000...SHEAR IS 20-40...AND SOME SUN TODAY. SPC HAS THE
FORECAST AREA IN A 5% PROBABILITY FOR WIND/HAIL WITH THE MARGINAL
INSTABILITY.
AN AREA OF WEAK HIGH PRESSURE WILL BUILD INTO THE REGION FROM THE
WEST LATE THIS EVENING. THIS WILL END THE THREAT FOR PRECIPITATION
FOR LATE FRIDAY NIGHT AND SATURDAY. HOWEVER..BY THE AFTERNOON...AN
AREA OF LOW PRESSURE ALONG WITH A UPPER TROUGH WILL MOVE INTO
WESTERN MINNESOTA AND WILL EFFECT THE REGION SATURDAY NIGHT.
.LONG TERM...(SATURDAY NIGHT THROUGH THURSDAY)
ISSUED AT 242 AM CDT FRI JUL 25 2014
THE MODELS ARE IN PRETTY GOOD AGREEMENT THROUGH MUCH OF THE
PERIOD. AN UPPER TROUGH OVER SOUTHERN MANITOBA SATURDAY EVENING
WILL DROP INTO NORTHERN MINNESOTA BY 12Z SUN...THEN CONTINUE INTO
SOUTHERN WISCONSIN BY SUNDAY EVENING. A SURFACE LOW/TROUGH AXIS
WILL BE ASSOCIATED WITH THIS UPPER WAVE. SHOWERS AND A FEW
THUNDERSTORMS WILL INCREASE IN COVERAGE SATURDAY NIGHT INTO SUNDAY
MORNING...THEN DECREASE FROM NORTH TO SOUTH SUNDAY
AFTERNOON/EVENING. SUNDAY NIGHT SHOULD BE DRY. WE HAVE THE HIGHEST
POPS OVER THE EASTERN PORTION OF THE NORTHLAND LATE SATURDAY NIGHT
INTO SUNDAY MORNING.
HIGH PRESSURE WILL THEN LEAD TO MAINLY DRY CONDITIONS SUNDAY NIGHT
INTO MONDAY NIGHT. THERE MAY BE A FEW SHOWERS TUESDAY INTO WEDNESDAY
OVER THE EASTERN HALF OF THE NORTHLAND WITH A SERIES OF SHORTWAVES
MOVING THROUGH IN THE NORTHERLY FLOW ALOFT. WE ALSO HAVE A SMALL
CHANCE FOR SHOWERS/STORMS THURSDAY FOR MOST AREAS.
THE PERIOD WILL START OUT WITH BELOW NORMAL TEMPERATURES
SUNDAY...WITH HIGHS IN THE MID SIXTIES TO LOWER SEVENTIES.
TEMPERATURES WILL THEN MODERATE THROUGH THE REST OF THE
PERIOD...REACHING THE UPPER SEVENTIES TO LOWER EIGHTIES BY THURSDAY.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SATURDAY MORNING)
ISSUED AT 632 AM CDT FRI JUL 25 2014
SHOWERS AND A FEW THUNDERSTORMS WERE MOVING THROUGH
CENTRAL/EASTERN PORTIONS OF THE NORTHLAND EARLY THIS MORNING. WE
EXPECT A LULL IN COVERAGE TO DEVELOP THIS MORNING...THEN
ADDITIONAL DEVELOPMENT THIS AFTERNOON AHEAD OF THE SURFACE
BOUNDARY THAT WILL ONLY MOVE SLOWLY FROM WESTERN MINNESOTA EARLY
THIS AFTERNOON TOWARD THE EAST.
AN AREA OF MVFR/IFR CEILINGS HAVE DEVELOPED OVER WEST CENTRAL
MINNESOTA INTO CENTRAL MINNESOTA. THE RAP IS SUGGESTS THESE
CEILINGS WILL SPREAD NORTH AND EAST TODAY. HOWEVER...THE COVERAGE
CURRENTLY IS NOT AS GREAT AS THE RAP SUGGESTS. WE FEEL MOST
CONFIDENT KBRD WILL SEE THE LOWER CEILINGS AND ADDED A TEMPO GROUP
FOR THE REST OF THE TAF SITES BY MID TO LATE MORNING.
THE COVERAGE OF THE PRECIPITATION WILL DIMINISH THIS EVENING AND
SOME FOG WILL BE POSSIBLE.
&&
.PRELIMINARY POINT TEMPS/POPS...
DLH 74 59 82 59 / 50 40 50 50
INL 75 57 81 56 / 40 40 50 60
BRD 79 58 84 60 / 60 20 30 40
HYR 75 62 85 58 / 60 30 30 50
ASX 75 61 81 57 / 40 40 40 50
&&
.DLH WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...NONE.
LS...NONE.
&&
$$
UPDATE...STEWART
SHORT TERM...STEWART
LONG TERM...MELDE
AVIATION...MELDE
AREA FORECAST DISCUSSION
NWS DULUTH MN
632 AM CDT FRI JUL 25 2014
.UPDATE...
ISSUED AT 430 AM CDT FRI JUL 25 2014
UPDATED TO INCREASE POPS ACROSS PORTIONS OF THE FORECAST AREA. AREA
OF SHOWERS AND THUNDERSTORMS MOVING ACROSS THOSE AREAS THIS
MORNING. THIS PRECIPITATION WILL END BY MID-MORNING. REST OF FCST UNCHANGED.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 242 AM CDT FRI JUL 25 2014
SHORT TERM CONCERN IS PRECIPITATION CHANCE TODAY AND TONIGHT.
CURRENT SURFACE ANALYSIS INDICATES RAIN SHOWERS NORTH OF THE IRON
RANGE AND IN THE ARROWHEAD. THESE SHOWERS ARE ASSOCIATED WITH A WEAK
SHORTWAVE MOVING THROUGH THE AREA. THEY WILL CONTINUE MOVE
SOUTHEAST AND SLOWLY DISSIPATE EARLY THIS MORNING. THERE IS AN
AREA OF THUNDERSTORMS ALONG THE ND/SD/WRN MN BORDER MOVING ESE.
THE AREA HAS DECREASED IN INTENSITY OVER THE PAST HOUR. THE
NORTHERN EDGE OF THE PRECIPITATION MAY CLIP CASS AND CROW WING
COUNTIES THIS MORNING. A WEAK SURFACE TROUGH WILL MOVE THROUGH MN
TODAY AND NW WI TONIGHT. IT WILL BRING ANOTHER ROUND OF SHOWERS
AND THUNDERSTORMS. THERE WILL BE SOME INCREASED INSTABILITY WITH
THE TROUGH THIS AFTERNOON AND EVENING. MUCAPES ARE
1500-2000...SHEAR IS 20-40...AND SOME SUN TODAY. SPC HAS THE
FORECAST AREA IN A 5% PROBABILITY FOR WIND/HAIL WITH THE MARGINAL
INSTABILITY.
AN AREA OF WEAK HIGH PRESSURE WILL BUILD INTO THE REGION FROM THE
WEST LATE THIS EVENING. THIS WILL END THE THREAT FOR PRECIPITATION
FOR LATE FRIDAY NIGHT AND SATURDAY. HOWEVER..BY THE AFTERNOON...AN
AREA OF LOW PRESSURE ALONG WITH A UPPER TROUGH WILL MOVE INTO
WESTERN MINNESOTA AND WILL EFFECT THE REGION SATURDAY NIGHT.
.LONG TERM...(SATURDAY NIGHT THROUGH THURSDAY)
ISSUED AT 242 AM CDT FRI JUL 25 2014
THE MODELS ARE IN PRETTY GOOD AGREEMENT THROUGH MUCH OF THE
PERIOD. AN UPPER TROUGH OVER SOUTHERN MANITOBA SATURDAY EVENING
WILL DROP INTO NORTHERN MINNESOTA BY 12Z SUN...THEN CONTINUE INTO
SOUTHERN WISCONSIN BY SUNDAY EVENING. A SURFACE LOW/TROUGH AXIS
WILL BE ASSOCIATED WITH THIS UPPER WAVE. SHOWERS AND A FEW
THUNDERSTORMS WILL INCREASE IN COVERAGE SATURDAY NIGHT INTO SUNDAY
MORNING...THEN DECREASE FROM NORTH TO SOUTH SUNDAY
AFTERNOON/EVENING. SUNDAY NIGHT SHOULD BE DRY. WE HAVE THE HIGHEST
POPS OVER THE EASTERN PORTION OF THE NORTHLAND LATE SATURDAY NIGHT
INTO SUNDAY MORNING.
HIGH PRESSURE WILL THEN LEAD TO MAINLY DRY CONDITIONS SUNDAY NIGHT
INTO MONDAY NIGHT. THERE MAY BE A FEW SHOWERS TUESDAY INTO WEDNESDAY
OVER THE EASTERN HALF OF THE NORTHLAND WITH A SERIES OF SHORTWAVES
MOVING THROUGH IN THE NORTHERLY FLOW ALOFT. WE ALSO HAVE A SMALL
CHANCE FOR SHOWERS/STORMS THURSDAY FOR MOST AREAS.
THE PERIOD WILL START OUT WITH BELOW NORMAL TEMPERATURES
SUNDAY...WITH HIGHS IN THE MID SIXTIES TO LOWER SEVENTIES.
TEMPERATURES WILL THEN MODERATE THROUGH THE REST OF THE
PERIOD...REACHING THE UPPER SEVENTIES TO LOWER EIGHTIES BY THURSDAY.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SATURDAY MORNING)
ISSUED AT 632 AM CDT FRI JUL 25 2014
SHOWERS AND A FEW THUNDERSTORMS WERE MOVING THROUGH
CENTRAL/EASTERN PORTIONS OF THE NORTHLAND EARLY THIS MORNING. WE
EXPECT A LULL IN COVERAGE TO DEVELOP THIS MORNING...THEN
ADDITIONAL DEVELOPMENT THIS AFTERNOON AHEAD OF THE SURFACE
BOUNDARY THAT WILL ONLY MOVE SLOWLY FROM WESTERN MINNESOTA EARLY
THIS AFTERNOON TOWARD THE EAST.
AN AREA OF MVFR/IFR CEILINGS HAVE DEVELOPED OVER WEST CENTRAL
MINNESOTA INTO CENTRAL MINNESOTA. THE RAP IS SUGGESTS THESE
CEILINGS WILL SPREAD NORTH AND EAST TODAY. HOWEVER...THE COVERAGE
CURRENTLY IS NOT AS GREAT AS THE RAP SUGGESTS. WE FEEL MOST
CONFIDENT KBRD WILL SEE THE LOWER CEILINGS AND ADDED A TEMPO GROUP
FOR THE REST OF THE TAF SITES BY MID TO LATE MORNING.
THE COVERAGE OF THE PRECIPITATION WILL DIMINISH THIS EVENING AND
SOME FOG WILL BE POSSIBLE.
&&
.PRELIMINARY POINT TEMPS/POPS...
DLH 74 59 82 59 / 50 40 20 50
INL 75 57 81 56 / 40 40 40 60
BRD 79 58 84 60 / 40 20 10 40
HYR 75 62 85 58 / 50 30 10 50
ASX 75 61 81 57 / 40 40 20 50
&&
.DLH WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...NONE.
LS...NONE.
&&
$$
UPDATE...STEWART
SHORT TERM...STEWART
LONG TERM...MELDE
AVIATION...MELDE
AREA FORECAST DISCUSSION
NWS TWIN CITIES/CHANHASSEN MN
602 AM CDT FRI JUL 25 2014
.UPDATED FOR 12Z AVIATION DISCUSSION...
ISSUED AT 556 AM CDT FRI JUL 25 2014
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 330 AM CDT FRI JUL 25 2014
EARLY MORNING THUNDERSTORMS CONTINUED TO DEVELOP ACROSS THE REGION
THIS MORNING FUELED BY THE VEERING WINDS ASSOCIATED WITH THE THETA_E
ADVECTION IN CONNECTION WITH THE LOW LEVEL JET. OVER THE NEXT FEW
HOURS THIS 40KT JET WILL BECOME MORE FOCUSED ACROSS SOUTHERN...AND
EVENTUALLY SOUTHEASTERN MN. AS A RESULT PRECIPITATION WILL CONTINUE
TO DEVELOP FOR THE NEXT FEW HOURS...BUT SHOULD GRADUALLY WANE
SHORTLY AFTER SUNSET AS IT ENTERS WESTERN WI.
EARLIER RUNS OF THE RAP MISSED THE PRECIP THAT DEVELOPED IN
NORTHEAST SD...SO IT IS NO SURPRISE THAT HIGHRES MODELS HAVE BEEN
STRUGGLING TO GET A HANDLE ON THE TWO AREAS OF PRECIP THAT DEVELOPED
EARLIER. AS A RESULT MOST OF THE RUNS HAVE BEEN ALL BUT DISCARDED.
THE 25.06HRRR HAS FINALLY CAUGHT UP AND IT SUPPORTS THE IDEA OF
CONTINUED CONVECTION THIS MORNING...BUT WITH A WEAKENING TREND AFTER
11Z. THE SEVERE WEATHER THREAT IS VERY LOW GIVEN THE DEEP STABLE
LAYER BENEATH THE ELEVATED CAPE...AND ONLY MARGINAL 30-35KTS OF
EFFECTIVE SHEAR.
LOOKING AHEAD...SKIES SHOULD CLEAR BEHIND THE MORNING PRECIP
YIELDING ANOTHER MUGGY AFTERNOON AS DEWPOINTS CLIMB BACK TO NEAR
70F. INCREASED TEMPS SLIGHTLY ACROSS WEST OF I35...AND RAISED
DEWPOINTS AS WELL. OVERNIGHT NORTHWESTERLY WINDS WILL PUSH A COLD
FRONT THROUGH THE REGION SENDING DEWPOINTS BACK INTO THE UPPER 50S
BY SATURDAY MORNING.
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 330 AM CDT FRI JUL 25 2014
THE WEEKEND STARTS OUT ON A MILD NOTE...AS THE AREA REMAINS
SANDWICHED BETWEEN A SOUTHERN CONUS RIDGE TO THE SOUTH...AND A
MID LEVEL LOW TO THE NORTH IN SASKATCHEWAN/MANITOBA. THE RESULT WILL
BE SLIGHTLY WARMER THAN NORMAL HIGHS IN THE MID 80S ON
SATURDAY...FOLLOWED BY INCREASING PRECIPITATION CHANCES INTO
SUNDAY AS THE AFOREMENTIONED LOW DROPS SOUTH-SOUTHEAST FROM
SOUTHERN MANITOBA. AS IS COMMON WITH THESE TYPES OF
LOWS...PRECIPITATION CHANCES APPEAR THE HIGHEST FROM CENTRAL MN
INTO WI...WHERE FORCING/MOISTURE IS DEEPER. EXPECT SHOWERS WITH
ISOLATED THUNDERSTORMS ON SUNDAY...PARTICULARLY DURING THE AFTERNOON
HOURS AS DIURNAL HEATING AIDS DESTABILIZATION.
NEXT WEEK STARTS OUT ON A DRY AND MILD NOTE AS THE WEEKEND LOW
SHIFTS SOUTHEAST AND A BROAD SURFACE RIDGE BUILDS ACROSS THE
CENTRAL CONUS. THE LOCAL AREA REMAINS CRAMMED BETWEEN WESTERN
RIDGING AND EASTERN TROUGHING AT THE MID TO UPPER LEVELS OF THE
ATMOSPHERE...YIELDING COOLER THAN NORMAL HIGHS FROM MONDAY THROUGH
WEDNESDAY MOSTLY IN THE 70S...AND LOWS IN THE 50S.
THURSDAY AND FRIDAY BRING THE NEXT CHANCE FOR MEASURABLE
PRECIPITATION AS SHORTWAVE ENERGY BEGINS TO TRICKLE SOUTH ON THE
WESTERN PERIPHERY OF THE EASTERN CONUS TROUGH. CHANCES ARE NOT
HIGH AT THIS POINT GIVEN MODEST FORCING AND MOISTURE...BUT
SUFFICIENT FOR THE INCLUSION OF 20-30 POPS.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SATURDAY MORNING)
ISSUED AT 556 AM CDT FRI JUL 25 2014
SHOWERS AND THUNDERSTORMS WILL CONTINUE TO WEAKEN AS THEM MOVE
ACROSS THE REGION THIS MORNING. FORECAST GUIDANCE WANTS TO SHOW A
FEW LOW CLOUDS ACROSS NORTHWEST MN LATER TODAY...BUT CONFIDENCE IS
TOO LOW TO INCLUDE IN THE TAF AT THIS TIME. LOOKING AHEAD...FOG
SHOULD DEVELOP AHEAD OF A COLD FRONT THAT IS FORECAST TO SLOWLY
MOVE ACROSS THE REGION LATER TODAY. THE BEST CHANCE FOR FOG IS
ACROSS THE EAST AT KRNH AND KEAU.
KMSP...
PRECIP WILL BE OUT OF THE REGION BEFORE 12Z...WITH VFR CONDITIONS
EXPECTED THROUGHOUT THE PERIOD. CHANCE FOR FOG IS LOW AT KMSP.
/OUTLOOK FOR KMSP/
SUN...VFR WITH MVFR/SHRA POSSIBLE. WINDS NW AT 10G15KTS.
MON...VFR. WINDS N AT 5KTS.
TUE...VFR. WINDS N AT 10KTS.
&&
.MPX WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...NONE.
&&
$$
SHORT TERM...JRB
LONG TERM...LS
AVIATION...JRB
AREA FORECAST DISCUSSION
NWS TWIN CITIES/CHANHASSEN MN
330 AM CDT FRI JUL 25 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 330 AM CDT FRI JUL 25 2014
EARLY MORNING THUNDERSTORMS CONTINUED TO DEVELOP ACROSS THE REGION
THIS MORNING FUELED BY THE VEERING WINDS ASSOCIATED WITH THE THETA_E
ADVECTION IN CONNECTION WITH THE LOW LEVEL JET. OVER THE NEXT FEW
HOURS THIS 40KT JET WILL BECOME MORE FOCUSED ACROSS SOUTHERN...AND
EVENTUALLY SOUTHEASTERN MN. AS A RESULT PRECIPITATION WILL CONTINUE
TO DEVELOP FOR THE NEXT FEW HOURS...BUT SHOULD GRADUALLY WANE
SHORTLY AFTER SUNSET AS IT ENTERS WESTERN WI.
EARLIER RUNS OF THE RAP MISSED THE PRECIP THAT DEVELOPED IN
NORTHEAST SD...SO IT IS NO SURPRISE THAT HIGHRES MODELS HAVE BEEN
STRUGGLING TO GET A HANDLE ON THE TWO AREAS OF PRECIP THAT DEVELOPED
EARLIER. AS A RESULT MOST OF THE RUNS HAVE BEEN ALL BUT DISCARDED.
THE 25.06HRRR HAS FINALLY CAUGHT UP AND IT SUPPORTS THE IDEA OF
CONTINUED CONVECTION THIS MORNING...BUT WITH A WEAKENING TREND AFTER
11Z. THE SEVERE WEATHER THREAT IS VERY LOW GIVEN THE DEEP STABLE
LAYER BENEATH THE ELEVATED CAPE...AND ONLY MARGINAL 30-35KTS OF
EFFECTIVE SHEAR.
LOOKING AHEAD...SKIES SHOULD CLEAR BEHIND THE MORNING PRECIP
YIELDING ANOTHER MUGGY AFTERNOON AS DEWPOINTS CLIMB BACK TO NEAR
70F. INCREASED TEMPS SLIGHTLY ACROSS WEST OF I35...AND RAISED
DEWPOINTS AS WELL. OVERNIGHT NORTHWESTERLY WINDS WILL PUSH A COLD
FRONT THROUGH THE REGION SENDING DEWPOINTS BACK INTO THE UPPER 50S
BY SATURDAY MORNING.
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 330 AM CDT FRI JUL 25 2014
THE WEEKEND STARTS OUT ON A MILD NOTE...AS THE AREA REMAINS
SANDWICHED BETWEEN A SOUTHERN CONUS RIDGE TO THE SOUTH...AND A
MID LEVEL LOW TO THE NORTH IN SASKATCHEWAN/MANITOBA. THE RESULT WILL
BE SLIGHTLY WARMER THAN NORMAL HIGHS IN THE MID 80S ON
SATURDAY...FOLLOWED BY INCREASING PRECIPITATION CHANCES INTO
SUNDAY AS THE AFOREMENTIONED LOW DROPS SOUTH-SOUTHEAST FROM
SOUTHERN MANITOBA. AS IS COMMON WITH THESE TYPES OF
LOWS...PRECIPITATION CHANCES APPEAR THE HIGHEST FROM CENTRAL MN
INTO WI...WHERE FORCING/MOISTURE IS DEEPER. EXPECT SHOWERS WITH
ISOLATED THUNDERSTORMS ON SUNDAY...PARTICULARLY DURING THE AFTERNOON
HOURS AS DIURNAL HEATING AIDS DESTABILIZATION.
NEXT WEEK STARTS OUT ON A DRY AND MILD NOTE AS THE WEEKEND LOW
SHIFTS SOUTHEAST AND A BROAD SURFACE RIDGE BUILDS ACROSS THE
CENTRAL CONUS. THE LOCAL AREA REMAINS CRAMMED BETWEEN WESTERN
RIDGING AND EASTERN TROUGHING AT THE MID TO UPPER LEVELS OF THE
ATMOSPHERE...YIELDING COOLER THAN NORMAL HIGHS FROM MONDAY THROUGH
WEDNESDAY MOSTLY IN THE 70S...AND LOWS IN THE 50S.
THURSDAY AND FRIDAY BRING THE NEXT CHANCE FOR MEASURABLE
PRECIPITATION AS SHORTWAVE ENERGY BEGINS TO TRICKLE SOUTH ON THE
WESTERN PERIPHERY OF THE EASTERN CONUS TROUGH. CHANCES ARE NOT
HIGH AT THIS POINT GIVEN MODEST FORCING AND MOISTURE...BUT
SUFFICIENT FOR THE INCLUSION OF 20-30 POPS.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z FRIDAY NIGHT)
ISSUED AT 1059 PM CDT THU JUL 24 2014
CONFIDENCE HAS INCREASED QUITE A BIT IN THE LAST FEW HOURS WITH
REGARD TO THE PRECIPITATION EVOLUTION OVERNIGHT INTO EARLY FRIDAY
MORNING. EXPECT TO SEE SHOWERS AND THUNDERSTORMS RAPIDLY DEVELOP
AROUND 07Z ACROSS SOUTHWESTERN MN AND EXPAND EASTWARD IN THE HOURS
FOLLOWING...REACHING STC AROUND 09Z...MSP AROUND 10Z...AND RNH BY
11Z. SOME THUNDER MAY ACCOMPANY THIS PRECIP...ESPECIALLY ACROSS
SOUTHERN AND WESTERN MN. ANY SHOWER/STORM ACTIVITY SHOULD DIMINISH
2 TO 4 HOURS AFTER IT BEGINS. FOLLOWING THE PRECIP...MODELS INSIST
ON DEVELOPING IFR OR MVFR CIGS. NOT CONFIDENT IN THIS SCENARIO AS
THEY HAVE OVERDONE THESE EVENTS TIME AND TIME AGAIN THIS SUMMER.
WILL CONTINUE THE SCT MENTION AROUND 2 KFT BEFORE CIGS RISE TOWARD
4 KFT BY AFTERNOON.
KMSP...CURRENT PROJECTIONS INDICATE PRECIP WILL ARRIVE AT MSP
AROUND 10Z AND PERSIST THROUGH ABOUT 12 OR 13Z. CONFIDENCE HAS
INCREASED AND BROUGHT BACK THE PREVAILING GROUP FOR THIS
TIMEFRAME.
/OUTLOOK FOR KMSP/
SAT...VFR. WINDS WSW AT 5-10KTS.
SUN...VFR. CHANCE SHRA/MVFR CIGS. WINDS NW AT 10-15 KTS.
MON...VFR. WINDS N 5 KT.
&&
.MPX WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...NONE.
&&
$$
SHORT TERM...JRB
LONG TERM...LS
AVIATION...BORGHOFF
AREA FORECAST DISCUSSION...UPDATED
NWS TWIN CITIES/CHANHASSEN MN
1106 PM CDT THU JUL 24 2014
.UPDATE...
ISSUED AT 804 PM CDT THU JUL 24 2014
ONLY UNTIL RECENTLY HAVE MODELS BEGUN TO LATCH ONTO THE CURRENT
SITUATION. HRRR AND NOW HOPWRF HAVE BEGUN TO CONVERGE TOWARD A
SOLUTION WHICH ALLOWS CONVECTION OVER THE WESTERN DAKOTAS AND
EASTERN MONTANA TO EXPAND EASTWARD RAPIDLY DURING THE LATE EVENING
AND SPILL INTO MINNESOTA OVERNIGHT. THE GLOBAL MODELS THROUGH 18Z
DID NOT HANDLE THIS IDEA WELL...SO WHILE CONFIDENCE HAS BEEN QUITE
LOW IT IS STARTING TO INCREASE. IT REMAINS TO BE SEEN WHETHER THE
00Z GLOBAL MODELS WILL LATCH ONTO THIS SOLUTION...BUT GIVEN THE
RECENT TRENDS IN THE CAMS THERE IS A PRETTY GOOD CHANCE.
STRONG MOISTURE ADVECTION OVER EASTERN SOUTH DAKOTA/NEBRASKA WHERE
PW VALUES ARE 1.5 TO 1.9 INCHES WILL CONTINUE TO IMPROVE OVERNIGHT
AS A 40 TO 50 KT LLJ DEVELOPS. THIS LLJ WILL THEN VEER EASTWARD INTO
SWRN MN OVERNIGHT AND FOCUS THIS MOISTURE TRANSPORT OVER THE MPX
CWA. A STRONGLY TO EXTREMELY UNSTABLE AIRMASS TO THE WEST SHOULD
MAINTAIN THIS DEVELOPING MCS AS IT CONTINUES EAST FOR THE NEXT 12
HOURS. THUS...THE SOLUTION KEEPING ACTIVITY CONFINED TO IOWA /A
LA NAM...GFS...AND CMC/ IS LOOKING LESS AND LESS LIKELY. INCREASED
POPS ACROSS CENTRAL MN INTO THE LIKELY RANGE AND THE TIMING WAS
BASED ON THE LATEST HRRR/HOPWRF.
ANY SEVERE THREAT WILL BE DETERMINED BY HOW FAR EAST THE EML AND
ASSOCIATED INSTABILITY CAN PROGRESS. BEST CHANCE FOR ANY SEVERE
WOULD BE ACROSS WRN MN...CLOSEST TO THE EML. LARGE HAIL WOULD BE
THE PRIMARY CONCERN.
&&
.SHORT TERM...(THIS EVENING THROUGH FRIDAY)
ISSUED AT 233 PM CDT THU JUL 24 2014
SHORT TERM CONCERNS REMAIN COVERAGE OF THUNDER OVERNIGHT INTO
FRIDAY. ALSO...CHANCE OF LARGE HAIL MAINLY LATER TONIGHT INTO SOUTH
CENTRAL MN WITH SOME SEVERE POTENTIAL LINGERING INTO FRIDAY AHEAD OF
FRONT.
UPPER RIDGE IS BEGINNING TO MOVE EAST WITH ONE IMPULSE DROPPING
SOUTHEAST OVER WESTERN MINNESOTA AND THE NEXT WAVE LIFTING INTO
NORTHWEST NODAK AND SOUTHERN MANITOBA. IT APPEARS THE INITIAL WAVE
WILL DROP SOUTHEAST THIS EVENING ALONG THE EASTERN PERIPHERY OF THE
INSTABILITY GRADIENT TO THE WEST AND THE EDGE OF LOW LEVEL WAA/STEEP
MID LEVEL LAPSE RATES. MODELS DIVERGE ON DEVELOPMENT THEREAFTER...
WITH SEVERAL HIRES MODELS INDICATING CANADIAN SYSTEM TAKES OVER AND
DROPS SOUTHEAST OVERNIGHT. STILL SOME POTENTIAL OF LLJ DRIVING
CONVECTION INTO MAINLY SOUTH CENTRAL MN LATE. WILL CARRY HIGHER
POPS TO THE SOUTH ONCE AGAIN...IN SPIRIT WITH THE PREVIOUS
FORECAST. SHOULD SEE SOME QPF MOVE THROUGH THE MOST OF AREA.
FRIDAY STILL SEE SOME POTENTIAL OF ISOLATED/WIDELY SCATTERED
CONVECTION DEVELOPING ALONG THE FRONT AS IT MOVES ACROSS THE EASTERN
PORTION OF THE AREA INTO THE AFTERNOON. WILL HOLD ONTO SOME LOW END
POPS FOR THIS POTENTIAL. INSTABILITY ALONG THE FRONT DOES INCREASE
DURING THE DAY BUT LOW LEVEL CONVERGENCE REMAINS WEAK. MUCH OF THE
HIGH END FORCING IS DRIVEN EAST DURING THE MORNING AS WELL.
TEMPERATURES SHOULD WARM INTO THE MID 80S TO THE SOUTHWEST WITH MIX
WITH THE WEAK FRONT AND UPPER 70S/LOWER 80S ELSEWHERE.
.LONG TERM...(FRIDAY NIGHT THROUGH THURSDAY)
ISSUED AT 233 PM CDT THU JUL 24 2014
MAIN CONCERN IN THE EXTENDED PERIOD IS WHETHER SHRA/TSRA DEVELOP
FURTHER SOUTHWARD ACROSS MN THAN EXPECTED FOR LATE SAT AFTN/EARLY
SUNDAY AS A STRONG...AND UNUSUAL UPPER LOW FOR THIS TIME OF YEAR
MOVES EAST-SE ACROSS THE NORTHERN PLAINS...AND INTO THE WESTERN
GREAT LAKES BY SUNDAY. WILL FOLLOW PREVIOUS FORECAST WITH THE MAIN
AREA OF SHRA ACROSS CENTRAL MN/EC MN AND WC WI WHERE BOTH UPPER
LEVEL ENERGY AND HIGHER RH FIELDS ARE EVIDENT. K-INDEX AND 85H
SHOWALTER INDEX FIELDS INDICATED MAINLY SHRA WITH SOME EMBEDDED
TSRA FOR THE TYPICAL DIURNAL TIME FRAME. SUNDAY MORNING/AFTN WILL
LIKELY BE BREEZY AS THE SFC LOW DEEPENS AS IT MOVES SE ACROSS THE
WESTERN GREAT LAKES IN RESPONSE TO THE UPPER JET.
NO CHGS IN THE EXTENDED PERIOD BEYOND THIS WEEKEND WITH BOTH THE
EC/GFS ADVERTISING A STRONG UPPER RIDGE BUILDING OFF THE EAST
COAST OF NORTH AMERICA WITH A DEEPENING LONG WAVE TROUGH ACROSS
THE EASTERN 1/3 OF THE CONUS. THIS WILL KEEP OUR REGION COOLER
THAN NORMAL AND MAINLY DRY. ALTHOUGH COOLER TEMPS ARE
EXPECTED...STANDARD ANOMALIES ARE NOT TOO IMPRESSIVE COMPARED TO
THE DEEP SE U.S. WHERE ANOMALIES COULD DROP TO 2-3 BLW NORMAL.
FOR COMPARISON...OUR REGION WILL BE SLIGHTLY COOLER...BUT STILL
NICE FOR LATE JULY/EARLY AUGUST.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z FRIDAY NIGHT)
ISSUED AT 1059 PM CDT THU JUL 24 2014
CONFIDENCE HAS INCREASED QUITE A BIT IN THE LAST FEW HOURS WITH
REGARD TO THE PRECIPITATION EVOLUTION OVERNIGHT INTO EARLY FRIDAY
MORNING. EXPECT TO SEE SHOWERS AND THUNDERSTORMS RAPIDLY DEVELOP
AROUND 07Z ACROSS SOUTHWESTERN MN AND EXPAND EASTWARD IN THE HOURS
FOLLOWING...REACHING STC AROUND 09Z...MSP AROUND 10Z...AND RNH BY
11Z. SOME THUNDER MAY ACCOMPANY THIS PRECIP...ESPECIALLY ACROSS
SOUTHERN AND WESTERN MN. ANY SHOWER/STORM ACTIVITY SHOULD DIMINISH
2 TO 4 HOURS AFTER IT BEGINS. FOLLOWING THE PRECIP...MODELS INSIST
ON DEVELOPING IFR OR MVFR CIGS. NOT CONFIDENT IN THIS SCENARIO AS
THEY HAVE OVERDONE THESE EVENTS TIME AND TIME AGAIN THIS SUMMER.
WILL CONTINUE THE SCT MENTION AROUND 2 KFT BEFORE CIGS RISE TOWARD
4 KFT BY AFTERNOON.
KMSP...CURRENT PROJECTIONS INDICATE PRECIP WILL ARRIVE AT MSP
AROUND 10Z AND PERSIST THROUGH ABOUT 12 OR 13Z. CONFIDENCE HAS
INCREASED AND BROUGHT BACK THE PREVAILING GROUP FOR THIS
TIMEFRAME.
/OUTLOOK FOR KMSP/
SAT...VFR. WINDS WSW AT 5-10KTS.
SUN...VFR. CHANCE SHRA/MVFR CIGS. WINDS NW AT 10-15 KTS.
MON...VFR. WINDS N 5 KT.
&&
.MPX WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...NONE.
&&
$$
UPDATE...BORGHOFF
SHORT TERM...DWE
LONG TERM...JLT
AVIATION...BORGHOFF
AREA FORECAST DISCUSSION...UPDATED
NWS ST LOUIS MO
942 PM CDT Sat Jul 26 2014
.UPDATE:
Issued at 935 PM CDT Sat Jul 26 2014
Trying to pin down convection threat for the remainder of tonight
remains somewhat of a head scratcher. However, as we dig into the
details of the 00z UA data becoming doubtful that the the storm-
free conditions we are currently experiencing will continue
throughout the entire night.
Although all of the 00z raobs in the area are indicating that the
strong cap is persisting throughout the region early this evening, water
vapor imagery indicates that strong mid level WNW flow is
beginning to dig south as trof rotates around the unseasonably
strong mid level low near nw MN, and this should drag some cooler
mid level air into northern sections of the CWA during the
predawn hours aiding in the erosion of this wedge of warm mid
level air. In addition to this cooling and dynamics with the
shortwave, low level forcing should also be increasing as cold
front works its way into the mid-Mississippi Valley. And...
while the "cooled" air from the rain associated with this
afternoon`s MCV is currently parked over the CWA, airmass west of
our area (that missed out on the rain) remains very unstable at
02z, with MLCAPES of 4000-5000 J/KG, and this air will be
advected back into our area due to weak but persistent westerly
low level flow.
So...whether the storms form upstream and advect into the area,
or form in situ near the Mississippi River as suggested by the
latest HRRR, 18z NAM, and latest RUC runs, thunderstorms will
remain in the forecast overnight. Overall, think current trends of
ramping PoPs up after 05z is very reasonable, with the greatest
PoPs over northern and central sections of the CWA, where forcing
should be the greatest. A conditional threat of severe
thunderstorm is still in the cards for the region as noted in the
SWODY1, as large scale shear will be increasing as the westerlies
dip into the mid- Mississippi Valley and interacts with the
residually unstable ams.
Truett
&&
.SHORT TERM: (Through Late Tonight)
Issued at 324 PM CDT Sat Jul 26 2014
Primary concern continues to be convective trends for this evening.
Current trends are pointing more and more toward there being less
severe weather in our CWFA than previously expected, with the
primary threat for severe storms further north/northeast in
southeast IA and central IL. A broad area of showers and stratiform
rain associated with an MCV which is spinning its way across the
state is putting the kibosh on much of the instability which was
forecast for late this afternoon/evening. A limited ribbon of very
high CAPE (MLCAPE in excess of 3500-4000 J/Kg) remains over extreme
northeast MO into southern IA and a much larger area of high CAPE
over central and southern IL. Storms are already rumbling just
north of our CWFA in southern IA and west central IL and I would
expect these areas of storms to continue to develop and strengthen.
Still cannot rule out severe storms from Kirksville to Quincy and
southeast to Litchfield and possibly Salem...but the probability
seems to be much lower than previously expected.
After the evening severe weather threat has passed, there is still
the possibility that there could be additional development
overnight. RAP and NAM both show moderate moisture convergence at
850mb ahead of the front and generate QPF in response. Have left
chance/slight chance PoPs going for most of the area through the
night. The wind shift associated with the approaching cold front
should be sliding into the northern 1/3 of our CWFA between 09-12Z
with drier low level air trying to nose in. This should effectively
cut off the chance for additional precip in those areas in the
pre-dawn hours.
Carney
.LONG TERM: (Sunday through Next Saturday)
Issued at 340 PM CDT Sat Jul 26 2014
The cold front is expected to push through early Sunday morning. A
minimal rain threat will exist during the morning near it, with a
dry afternoon on tap behind it. The cooling effects will not be
felt too much early on, with another warm day expected: max temps
still look to top 90 degrees for most areas near and south of I-70.
The big difference will be lower humidity from today, however.
After Sunday, an extended dry period is forecast as a deep longwave
upper TROF sets up over eastern North America with a stout NW flow
aloft for our region. This usually means either dry, or surprise
hit-and-run systems this time of year, but almost always means below
average temps. For now, am going with dry until Thursday, with low
PoPs thereafter as a system works its way down into our region and
stays for a bit.
TES
&&
.AVIATION: (For the 00z TAFs through 00z Sunday Evening)
Issued at 655 PM CDT Sat Jul 26 2014
Mesoscale Convective Vortex (MCV) moved across north central
Missouri through southwest Illinois. Scattered light showers was
associated with the MVC while strong thunderstorms first formed
along the northeast quadrant of the MVC and eventually build ahead
of this featuer over central and parts of southeast Illinois.
Scattered light showers will continue over STL terminarls but will
end over UIN and eventually end over COU after 0200 UTC. Cold
front will move through UIN and COU between 0800 and 1000 UTC and
STL area after 1200 UTC. Scattered showers and thunderstorms still
possible with the passage of the cold front.
Specifics for KSTL:
Scattered showers will continue over area through 0200 UTC then
next chance for scattered showers and thunderstorms may occur with
the passage of the cold front before 1200 UTC. Southwest winds
will become northwest 10 to 15 mph after the passage of the cold
front.
Przybylinski
&&
.LSX WATCHES/WARNINGS/ADVISORIES:
MO...NONE.
IL...NONE.
&&
$$
WFO LSX
AREA FORECAST DISCUSSION...UPDATED AVIATION
NWS ST LOUIS MO
712 PM CDT Sat Jul 26 2014
.SHORT TERM: (Through Late Tonight)
Issued at 324 PM CDT Sat Jul 26 2014
Primary concern continues to be convective trends for this evening.
Current trends are pointing more and more toward there being less
severe weather in our CWFA than previously expected, with the
primary threat for severe storms further north/northeast in
southeast IA and central IL. A broad area of showers and stratiform
rain associated with an MCV which is spinning its way across the
state is putting the kibosh on much of the instability which was
forecast for late this afternoon/evening. A limited ribbon of very
high CAPE (MLCAPE in excess of 3500-4000 J/Kg) remains over extreme
northeast MO into southern IA and a much larger area of high CAPE
over central and southern IL. Storms are already rumbling just
north of our CWFA in southern IA and west central IL and I would
expect these areas of storms to continue to develop and strengthen.
Still cannot rule out severe storms from Kirksville to Quincy and
southeast to Litchfield and possibly Salem...but the probability
seems to be much lower than previously expected.
After the evening severe weather threat has passed, there is still
the possibility that there could be additional development
overnight. RAP and NAM both show moderate moisture convergence at
850mb ahead of the front and generate QPF in response. Have left
chance/slight chance PoPs going for most of the area through the
night. The wind shift associated with the approaching cold front
should be sliding into the northern 1/3 of our CWFA between 09-12Z
with drier low level air trying to nose in. This should effectively
cut off the chance for additional precip in those areas in the
pre-dawn hours.
Carney
.LONG TERM: (Sunday through Next Saturday)
Issued at 340 PM CDT Sat Jul 26 2014
The cold front is expected to push through early Sunday morning. A
minimal rain threat will exist during the morning near it, with a
dry afternoon on tap behind it. The cooling effects will not be
felt too much early on, with another warm day expected: max temps
still look to top 90 degrees for most areas near and south of I-70.
The big difference will be lower humidity from today, however.
After Sunday, an extended dry period is forecast as a deep longwave
upper TROF sets up over eastern North America with a stout NW flow
aloft for our region. This usually means either dry, or surprise
hit-and-run systems this time of year, but almost always means below
average temps. For now, am going with dry until Thursday, with low
PoPs thereafter as a system works its way down into our region and
stays for a bit.
TES
&&
.AVIATION: (For the 00z TAFs through 00z Sunday Evening)
Issued at 655 PM CDT Sat Jul 26 2014
Mesoscale Convective Vortex (MCV) moved across north central
Missouri through southwest Illinois. Scattered light showers was
associated with the MVC while strong thunderstorms first formed
along the northeast quadrant of the MVC and eventually build ahead
of this featuer over central and parts of southeast Illinois.
Scattered light showers will continue over STL terminarls but will
end over UIN and eventually end over COU after 0200 UTC. Cold
front will move through UIN and COU between 0800 and 1000 UTC and
STL area after 1200 UTC. Scattered showers and thunderstorms still
possible with the passage of the cold front.
Specifics for KSTL:
Scattered showers will continue over area through 0200 UTC then
next chance for scattered showers and thunderstorms may occur with
the passage of the cold front before 1200 UTC. Southwest winds
will become northwest 10 to 15 mph after the passage of the cold
front.
Przybylinski
&&
.LSX WATCHES/WARNINGS/ADVISORIES:
MO...NONE.
IL...NONE.
&&
$$
WFO LSX
AREA FORECAST DISCUSSION...UPDATED AVIATION
NWS ST LOUIS MO
1255 PM CDT Fri Jul 25 2014
.UPDATE:
Issued at 950 AM CDT Fri Jul 25 2014
Complex of TSRA continues to maintain itself rather well on its
backside over northeast MO and eastern IA, where lo level jet and
better instability are feeding it. An isolated threat for large
hail exists, but should decrease heading deeper into the morning.
Overall health of TSRA complex should also begin to fail as we
head into the afternoon hours, with strengthening cap of warm air
to the west and weakening lo level jet. This rain should have a
somewhat easier time of advecting in IL versus MO and updated the
forecast accordingly, although will no doubt need to tweak
expected coverage over the next couple hours.
Also adjusted temps further down in IL, where readings should stay
below 80F, but enough recovery expected in the west and south to
maintain previous forecast.
TES
&&
.SHORT TERM: (Through Late This Afternoon)
Issued at 330 AM CDT Fri Jul 25 2014
Convective trends and the extent of pops are the biggest forecast
challenge today. Thunderstorms have blossomed within the last
several hours across central Iowa at the terminus of a stout
southwesterly LLJ, and along the eastern periphery of elevated
instability, deeper moisture and steep mid level lapse rates.
Short range guidance shows the LLJ slowly veering this morning,
providing favorable moisture transport and forcing as the flow
aloft and northwestely deep layer shear steer the activity east
and southeastward. The HRRR runs since 01Z have been very emphatic
supporting this scenario bringing showers and thunderstorms into
northeast Missouri and west central Illinois. I have increased
pops into the likely range in this area tapered to slight chances
just north of interstate 70. Believe that most of this activity
will be east of the MS river by early afternoon and exiting the
CWA shortly thereafter. This activity will likely delay/impeed the
northward retreat of the warm front, however in central MO there
should be no issue where highs will be around 90.
Glass
.LONG TERM: (Tonight through Thursday)
Issued at 330 AM CDT Fri Jul 25 2014
The warm front should have exited the entire CWA by early evening
while the upstream cold frontal system will be slowly advancing
and stretching from the upper MS valley into the central Plains.
High heights aloft and warm mid level temperatures should suppress
any surface-based storm development within the large warm sector
spanning the CWA, however the area will remain subject to an
elevated shower and thunderstorm threat. While there is no defined
focus for thunderstorms, a westerly LLJ will be poised across the
area in conjunction with steep mid level lapse rates and good
elevated instability supporting a least a chance pop. These same
unfocused conditions will exist on Saturday morning. The set-up
should improve on Saturday afternoon. Strong surface heating
should yield temperatures well into the 90s with dew points in the
70s. This will result in afternoon heat indices in the 100-104 degree
range, just below advisory criteria. We will need to monitor this
closely as just a bit higher dew points and/or temperatures and a
heat advisory will be warranted. The aforementioned conditions along
with the presence of steep mid level lapse rates will yield very
unstable conditions during the afternoon/evening. There are
indications that the combo of heating and a disturbance in the
west northwest flow aloft should sufficiently weaken the cap
allowing for robust thunderstorm development along the west-east
oriented front stretching in the vicinity of far northern MO
through central IL into the OH valley. How far west development
occurs is uncertain but height falls/cooling aloft on Saturday
night could aid this process. Deep layer shear and instability is
quite favorable for organized severe with damaging winds the most
apparent severe threat at this time. I have some low pops on
Sunday ahead of the advancing front, but the overall threat of
precipitation will be lower as compared to the Saturday night.
Cooler and drier air will advect in earnest into the area on Sunday
night with a large surface high settling into the Nation`s
midsection on Monday. An unseasonably deep upper trof over eastern
NOAM through the first part of next week will keep the large
surface high in control and allow for another period of below
average temperatures as we exit July and head into August.
Glass
&&
.AVIATION: (For the 18z TAFs through 18z Saturday Afternoon)
Issued at 1255 PM CDT Fri Jul 25 2014
VFR conditions are expected to prevail outside of TSRA at the TAF
sites thru the valid period. TSRA expected to weaken as it moves
into STL metro with some activity expected to edge into the
northern vicinities of SUS and STL before final anticipated
dissolution. The TSRA is in the process of exiting UIN now. After
this, very iffy on TSRA chances heading into tonight and thru the
first part of Saturday...enough to preclude mention in TAFs.
Otherwise, look for veering wind directions from SE to SW.
Specifics for KSTL: VFR thru the period outside of TSRA with
veering SE winds to SW by Saturday. Current TSRA activity still
expected to fall apart before reaching the aerodrome, but believe
something will edge the northern vicinity before doing so.
TES
&&
.LSX WATCHES/WARNINGS/ADVISORIES:
MO...NONE.
IL...NONE.
&&
$$
WFO LSX
AREA FORECAST DISCUSSION...UPDATED
NWS ST LOUIS MO
950 AM CDT Fri Jul 25 2014
.UPDATE:
Issued at 950 AM CDT Fri Jul 25 2014
Complex of TSRA continues to maintain itself rather well on its
backside over northeast MO and eastern IA, where lo level jet and
better instability are feeding it. An isolated threat for large
hail exists, but should decrease heading deeper into the morning.
Overall health of TSRA complex should also begin to fail as we
head into the afternoon hours, with strengthening cap of warm air
to the west and weakening lo level jet. This rain should have a
somewhat easier time of advecting in IL versus MO and updated the
forecast accordingly, although will no doubt need to tweak
expected coverage over the next couple hours.
Also adjusted temps further down in IL, where readings should stay
below 80F, but enough recovery expected in the west and south to
maintain previous forecast.
TES
&&
.SHORT TERM: (Through Late This Afternoon)
Issued at 330 AM CDT Fri Jul 25 2014
Convective trends and the extent of pops are the biggest forecast
challenge today. Thunderstorms have blossomed within the last
several hours across central Iowa at the terminus of a stout
southwesterly LLJ, and along the eastern periphery of elevated
instability, deeper moisture and steep mid level lapse rates.
Short range guidance shows the LLJ slowly veering this morning,
providing favorable moisture transport and forcing as the flow
aloft and northwestely deep layer shear steer the activity east
and southeastward. The HRRR runs since 01Z have been very emphatic
supporting this scenario bringing showers and thunderstorms into
northeast Missouri and west central Illinois. I have increased
pops into the likely range in this area tapered to slight chances
just north of interstate 70. Believe that most of this activity
will be east of the MS river by early afternoon and exiting the
CWA shortly thereafter. This activity will likely delay/impeed the
northward retreat of the warm front, however in central MO there
should be no issue where highs will be around 90.
Glass
.LONG TERM: (Tonight through Thursday)
Issued at 330 AM CDT Fri Jul 25 2014
The warm front should have exited the entire CWA by early evening
while the upstream cold frontal system will be slowly advancing
and stretching from the upper MS valley into the central Plains.
High heights aloft and warm mid level temperatures should suppress
any surface-based storm development within the large warm sector
spanning the CWA, however the area will remain subject to an
elevated shower and thunderstorm threat. While there is no defined
focus for thunderstorms, a westerly LLJ will be poised across the
area in conjunction with steep mid level lapse rates and good
elevated instability supporting a least a chance pop. These same
unfocused conditions will exist on Saturday morning. The set-up
should improve on Saturday afternoon. Strong surface heating
should yield temperatures well into the 90s with dew points in the
70s. This will result in afternoon heat indices in the 100-104 degree
range, just below advisory criteria. We will need to monitor this
closely as just a bit higher dew points and/or temperatures and a
heat advisory will be warranted. The aforementioned conditions along
with the presence of steep mid level lapse rates will yield very
unstable conditions during the afternoon/evening. There are
indications that the combo of heating and a disturbance in the
west northwest flow aloft should sufficiently weaken the cap
allowing for robust thunderstorm development along the west-east
oriented front stretching in the vicinity of far northern MO
through central IL into the OH valley. How far west development
occurs is uncertain but height falls/cooling aloft on Saturday
night could aid this process. Deep layer shear and instability is
quite favorable for organized severe with damaging winds the most
apparent severe threat at this time. I have some low pops on
Sunday ahead of the advancing front, but the overall threat of
precipitation will be lower as compared to the Saturday night.
Cooler and drier air will advect in earnest into the area on Sunday
night with a large surface high settling into the Nation`s
midsection on Monday. An unseasonably deep upper trof over eastern
NOAM through the first part of next week will keep the large
surface high in control and allow for another period of below
average temperatures as we exit July and head into August.
Glass
&&
.AVIATION: (For the 12z TAFs through 12z Saturday Morning)
Issued at 519 AM CDT Fri Jul 25 2014
Cluster of thunderstorms over southeastern Iowa will continue
tracking southeastward and will arrive at the KUIN TAF site by
around 12z. VSBYS may fall to high end of MVFR range as the
storms pass, but cigs will likely remain AOA 6K feet. Storms will
move into more stable atmosphere as they approach the St. Louis
metro TAF sites, and most model output suggests little or no
precip there. With that in mind, will keep all St. Louis area TAFS
dry. South winds will increase this afternoon.
Specifics for KSTL: Thunderstorms approaching from the northwest
should dissipate before moving into KSTL TAF site as they move
into more stable air. High clouds will remain through
at least midday...with south winds increasing to 10 to 14 mph by
afternoon.
Browning
&&
.LSX WATCHES/WARNINGS/ADVISORIES:
MO...NONE.
IL...NONE.
&&
$$
WFO LSX
AREA FORECAST DISCUSSION...UPDATED AVIATION
NWS ST LOUIS MO
533 AM CDT Fri Jul 25 2014
.SHORT TERM: (Through Late This Afternoon)
Issued at 330 AM CDT Fri Jul 25 2014
Convective trends and the extent of pops are the biggest forecast
challenge today. Thunderstorms have blossomed within the last
several hours across central Iowa at the terminus of a stout
southwesterly LLJ, and along the eastern periphery of elevated
instability, deeper moisture and steep mid level lapse rates.
Short range guidance shows the LLJ slowly veering this morning,
providing favorable moisture transport and forcing as the flow
aloft and northwestely deep layer shear steer the activity east
and southeastward. The HRRR runs since 01Z have been very emphatic
supporting this scenario bringing showers and thunderstorms into
northeast Missouri and west central Illinois. I have increased
pops into the likely range in this area tapered to slight chances
just north of interstate 70. Believe that most of this activity
will be east of the MS river by early afternoon and exiting the
CWA shortly thereafter. This activity will likely delay/impeed the
northward retreat of the warm front, however in central MO there
should be no issue where highs will be around 90.
Glass
.LONG TERM: (Tonight through Thursday)
Issued at 330 AM CDT Fri Jul 25 2014
The warm front should have exited the entire CWA by early evening
while the upstream cold frontal system will be slowly advancing
and stretching from the upper MS valley into the central Plains.
High heights aloft and warm mid level temperatures should suppress
any surface-based storm development within the large warm sector
spanning the CWA, however the area will remain subject to an
elevated shower and thunderstorm threat. While there is no defined
focus for thunderstorms, a westerly LLJ will be poised across the
area in conjunction with steep mid level lapse rates and good
elevated instability supporting a least a chance pop. These same
unfocused conditions will exist on Saturday morning. The set-up
should improve on Saturday afternoon. Strong surface heating
should yield temperatures well into the 90s with dew points in the
70s. This will result in afternoon heat indices in the 100-104 degree
range, just below advisory criteria. We will need to monitor this
closely as just a bit higher dew points and/or temperatures and a
heat advisory will be warranted. The aforementioned conditions along
with the presence of steep mid level lapse rates will yield very
unstable conditions during the afternoon/evening. There are
indications that the combo of heating and a disturbance in the
west northwest flow aloft should sufficiently weaken the cap
allowing for robust thunderstorm development along the west-east
oriented front stretching in the vicinity of far northern MO
through central IL into the OH valley. How far west development
occurs is uncertain but height falls/cooling aloft on Saturday
night could aid this process. Deep layer shear and instability is
quite favorable for organized severe with damaging winds the most
apparent severe threat at this time. I have some low pops on
Sunday ahead of the advancing front, but the overall threat of
precipitation will be lower as compared to the Saturday night.
Cooler and drier air will advect in earnest into the area on Sunday
night with a large surface high settling into the Nation`s
midsection on Monday. An unseasonably deep upper trof over eastern
NOAM through the first part of next week will keep the large
surface high in control and allow for another period of below
average temperatures as we exit July and head into August.
Glass
&&
.AVIATION: (For the 12z TAFs through 12z Saturday Morning)
Issued at 519 AM CDT Fri Jul 25 2014
Cluster of thunderstorms over southeastern Iowa will continue
tracking southeastward and will arrive at the KUIN TAF site by
around 12z. VSBYS may fall to high end of MVFR range as the
storms pass, but cigs will likely remain AOA 6K feet. Storms will
move into more stable atmosphere as they approach the St. Louis
metro TAF sites, and most model output suggests little or no
precip there. With that in mind, will keep all St. Louis area TAFS
dry. South winds will increase this afternoon.
Specifics for KSTL: Thunderstorms approaching from the northwest
should dissipate before moving into KSTL TAF site as they move
into more stable air. High clouds will remain through
at least midday...with south winds increasing to 10 to 14 mph by
afternoon.
Browning
&&
.LSX WATCHES/WARNINGS/ADVISORIES:
MO...NONE.
IL...NONE.
&&
$$
WFO LSX
AREA FORECAST DISCUSSION
NWS ST LOUIS MO
346 AM CDT Fri Jul 25 2014
.SHORT TERM: (Through Late This Afternoon)
Issued at 330 AM CDT Fri Jul 25 2014
Convective trends and the extent of pops are the biggest forecast
challenge today. Thunderstorms have blossomed within the last
several hours across central Iowa at the terminus of a stout
southwesterly LLJ, and along the eastern periphery of elevated
instability, deeper moisture and steep mid level lapse rates.
Short range guidance shows the LLJ slowly veering this morning,
providing favorable moisture transport and forcing as the flow
aloft and northwestely deep layer shear steer the activity east
and southeastward. The HRRR runs since 01Z have been very emphatic
supporting this scenario bringing showers and thunderstorms into
northeast Missouri and west central Illinois. I have increased
pops into the likely range in this area tapered to slight chances
just north of interstate 70. Believe that most of this activity
will be east of the MS river by early afternoon and exiting the
CWA shortly thereafter. This activity will likely delay/impeed the
northward retreat of the warm front, however in central MO there
should be no issue where highs will be around 90.
Glass
.LONG TERM: (Tonight through Thursday)
Issued at 330 AM CDT Fri Jul 25 2014
The warm front should have exited the entire CWA by early evening
while the upstream cold frontal system will be slowly advancing
and stretching from the upper MS valley into the central Plains.
High heights aloft and warm mid level temperatures should suppress
any surface-based storm development within the large warm sector
spanning the CWA, however the area will remain subject to an
elevated shower and thunderstorm threat. While there is no defined
focus for thuunderstorms, a westerly LLJ will be poised across the
area in conjunction with steep mid level lapse rates and good
elevated instability supporting a least a chance pop. These same
unfocused conditions will exist on Saturday morning. The set-up
should improve on Saturday afternoon. Strong surface heating
should yield temperatures well into the 90s with dew points in the
70s. This will result in afternoon heat indices in the 100-104 degree
range, just below advisory criteria. We will need to monitor this
closely as just a bit higher dew points and/or temperatures and a
heat advisory will be warranted. The aforementioned conditions along
with the presence of steep mid level lapse rates will yield very
unstable conditions during the afternoon/evening. There are
indications that the combo of heating and a disturbance in the
west northwest flow aloft should sufficiently weaken the cap
allowing for robust thunderstorm development along the west-east
oriented front stretching in the vicinity of far northern MO
through central IL into the OH valley. How far west development
occurs is uncertain but height falls/cooling aloft on Saturday
night could aid this process. Deep layer shear and instability is
quite favorable for organized severe with damaging winds the most
apparent severe threat at this time. I have some low pops on
Sunday ahead of the advancing front, but the overall threat of
precipitation will be lower as compared to the Saturday night.
Cooler and drier air will advect in ernest into the area on Sunday
night with a large surface high settling into the Nation`s
midsection on Monday. An unseasonably deep upper trof over eastern
NOAM through the first part of next week will keep the large
surface high in control and allow for another period of below
average temperatures as we exit July and head into August.
Glass
&&
.AVIATION: (For the 06z TAFs through 06z Friday Night)
Issued at 1111 PM CDT Thu Jul 24 2014
VFR fcst with the only real concern being new convection fcst to
dvlp around 8-9Z across cntrl IA out ahead of the ongoing
convection across ern NEB. This new activity is fcst to drop SE
during the early mrng hrs making it as far SE as NE MO and W cntrl
IL by daybreak. There is some question as to how far SE this
precip will be able to push before dssptng...but given how far the
precip from earlier this evng made it...wouldn`t be at all
surprised if it made it all the way into the STL metro area by
17-18Z. Given the uncertainty in intensity...coverage and timing have
left the metro sites dry for now. After this activity passes SE of
the terminals...expect srly winds with just some left over
mid/high clouds
Specifics for KSTL:
VFR fcst with the possibility of precip mvng into the terminal around
noon. Convection is fcst to dvlp across IA after midnight and then
track SE thru the mrng possibly reaching the terminal by very late
mrng. There is still some question as to whether the precip will
hold together that long...hence have a dry fcst attm. This is
something that will obviously need to be monitored for future
updates. Otherwise...expect srly winds with mid/high level
cloudiness.
2%
&&
.LSX WATCHES/WARNINGS/ADVISORIES:
MO...NONE.
IL...NONE.
&&
$$
WFO LSX
AREA FORECAST DISCUSSION
NWS HASTINGS NE
100 AM CDT FRI JUL 25 2014
.SHORT TERM...(THIS EVENING THROUGH FRIDAY)
ISSUED AT 332 PM CDT THU JUL 24 2014
FAIRLY QUIET DAY WITH MOSTLY SUNNY SKIES AS THE UPPER LEVEL RIDGE
AXIS CONTINUES TO MOVE OVERHEAD. 12Z SUBJECTIVE UPPER AIR ANALYSIS
IN ADDITION TO RAP ANALYSIS SHOWS A STOUT MID LEVEL WARM POCKET OVER
THE HIGH PLAINS REGION. THIS CONTINUES TO DRIFT EWD WHICH WOULD
TYPICALLY CAP OFF ANY POTENTIAL THUNDERSTORM DEVELOPMENT. THIS BEING
SAID...AN AREA OF CONVECTION HAS MANAGED TO DEVELOP OVER THE
NEBRASKA PANHANDLE AND PORTIONS OF NORTHEAST COLORADO IN ADVANCE OF
A WEAK VORT MAX. LATEST RUNS OF THE HRRR AND RAP INDICATE THIS
CONVECTION HOLDING ON AND SPREADING EAST THROUGHOUT THE LATER
EVENING HOURS. AS A RESULT...WILL HOLD ONTO SMALL POPS ACROSS THE
NORTHERN CWA.
ATTENTION THEN TURNS TO HEAT TOMORROW. HIGHS SHOULD REACH THE 100
DEGREE MARK ACROSS THE KANSAS COUNTIES WITH UPPER 90S SOUTH OF
INTERSTATE 80. COMBINED WITH SFC DEWPOINTS IN THE UPPER 60S...WE
SHOULD APPROACH HEAT INDICES IN THE 105+ RANGE. AS A RESULT...WILL
GO AHEAD AND ISSUE A HEAT ADVISORY FOR PORTIONS OF SOUTH CENTRAL
NEBRASKA AND ALL THE NORTH CENTRAL KANSAS COUNTIES.
.LONG TERM...(FRIDAY NIGHT THROUGH THURSDAY)
ISSUED AT 332 PM CDT THU JUL 24 2014
ANOTHER HOT DAY IS EXPECTED ON SATURDAY WITH POTENTIAL FOR HEAT
ADVISORY CRITERIA AGAIN. WILL LET LATER SHIFTS EVALUATE FOR
ADDITIONAL HEADLINES. A COLD FRONT WILL DROP OVER THE AREA SATURDAY
NIGHT WITH HIGH PRESSURE BUILDING ACROSS THE AREA SUNDAY INTO
MONDAY. MUCH COOLER AND DRIER AIRMASS WILL ALLOW TEMPS TO DROP INTO
THE LOW 80S FOR HIGHS AND LOW 60S FOR LOWS.
RETURN FLOW WILL SET UP EARLY NEXT WEEK WHILE A SERIES OF UPPER
LEVEL SHORTWAVES ARE FORECAST TO PASS THROUGH THE REGION IN
MID/UPPER LEVEL NORTHWESTERLY FLOW. MODEL CONSENSUS HAS PUT AT LEAST
A SLIGHT CHANCE OR CHANCE OF TSTMS FROM MONDAY NIGHT THROUGH
THURSDAY. ALTHOUGH WIDESPREAD CONTINUOUS PCPN IS NOT
ANTICIPATED...WILL LEAVE THESE CHANCES IN DUE TO UNCERTAINTY.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z FRIDAY NIGHT)
ISSUED AT 1255 AM CDT FRI JUL 25 2014
BIGGEST CONCERN IS LOW-LEVEL WIND SHEAR OVERNIGHT INTO EARLY
FRIDAY MORNING. ALSO...WIND WILL EVENTUALLY VEER OVERNIGHT AS A
COLD FRONT APPROACHES FROM THE NORTH. VFR CONDITIONS ARE FORECAST.
ANY THUNDERSTORMS SHOULD REMAIN NORTH AND EAST OVERNIGHT...AND
THUNDERSTORMS FRIDAY NIGHT WILL REMAIN NORTH AND MOSTLY DURING THE
OVERNIGHT.
&&
.GID WATCHES/WARNINGS/ADVISORIES...
NE...HEAT ADVISORY FROM NOON TODAY TO 7 PM CDT THIS EVENING FOR
NEZ063-064-074>077-083>087.
KS...HEAT ADVISORY FROM NOON TODAY TO 7 PM CDT THIS EVENING FOR
KSZ005>007-017>019.
&&
$$
SHORT TERM...KERN
LONG TERM...KERN
AVIATION...HEINLEIN
AREA FORECAST DISCUSSION
NWS OMAHA/VALLEY NE
1130 PM CDT THU JUL 24 2014
.UPDATE...
ISSUED AT 1130 PM CDT THU JUL 24 2014
CLUSTER OF THUNDERSTORMS NOW MOVING INTO NORTHEAST NEBRASKA SEEMS
TO MAINTAINING ITSELF BASED ON RADAR/LIGHTNING/SATELLITE TRENDS...
AND COULD VERY WELL CONTINUE ROLL EAST SOUTHEAST AS IT REMAINS
WITHIN A LOW LEVEL MOIST JET AXIS TONIGHT. MOST RECENT HRRR MODEL
RUNS SEEM TO CAPTURE THIS TREND WELL...THUS THE FORECAST WAS
UPDATED TO AT LEAST INCLUDE SOME CHANCE OF RAIN ACROSS THE
REMAINDER OF THE FORECAST AREA. BEST CHANCES WILL LIE ALONG THE
PLATTE RIVER BASIN. FREEZING LEVEL IS AROUND 15000 FEET AND WET
BULB ZERO LEVELS AROUND 11600 FEET. THUS LARGE HAIL WILL BE HARD
TO ACHIEVE...BUT SMALL HAIL MAY BE POSSIBLE IN THE STRONGER STORMS.
30 TO 45 MPH GUSTY WINDS WILL BE POSSIBLE AS STORMS MOVE IN.
A COUPLE OF SPOTTY SHOWERS WERE ALSO TRYING TO DEVELOP AROUND THE
KSUX AREA...AND THIS MAY BE THE PRECURSOR TO ACTIVITY THAT WILL
MOVE THROUGH CENTRAL IOWA...BUT THE WESTERN EDGE COULD ALSO CLIP
OUR COUNTIES IN WESTERN IOWA AS WELL.
UPDATE ISSUED AT 847 PM CDT THU JUL 24 2014
ALTHOUGH 00Z OMAHA SOUNDING AND SPC MESO-ANALYSIS PAGE INDICATED A
FORMIDABLE CAP/WARM MID LEVEL TEMPERATURES ACROSS THE
FA...ELEVATED CONVECTION CONTINUED TO DEVELOP TOWARD NWRN ZONES
SHORTLY BEFORE 02Z. RADAR TRENDS WOULD PUT SCATTERED ACTIVITY
TOWARD ALBION BY 03-04Z. UPDATED GRIDS/ZONES TO INCLUDE POPS AS
FAR EAST AS LINCOLN TO NEAR FREMONT THROUGH 07Z BEFORE PRECIP
POSSIBLY SHUTS OFF DUE TO ITS FARTHER EAST REMOVAL OF ITS ELEVATED
ROOTS. HOWEVER...CONFIDENCE IS LOW IN THIS AND SOME SHORT RANGE
MODELS BROUGHT AN MCS ACROSS LINCOLN/OMAHA TONIGHT. SECOND AREA
WHERE DEVELOPMENT IS POSSIBLE LATER WOULD NEAR EDGE OF WARMER
TEMPS ALOFT/CAP...ACROSS FAR ERN ZONES. NO MENTION WAS MADE THERE
JUST YET. NEEDLESS TO SAY...RADAR IMAGERY WILL CONTINUED TO BE
MONITORED FOR ADDITIONAL UPDATES.
&&
.SHORT TERM...(TONIGHT THROUGH SUNDAY)
ISSUED AT 316 PM CDT THU JUL 24 2014
MOST OF THE SENSIBLE WEATHER THIS FORECAST IS IN THE SHORT TERM.
TSRA ASSOCIATED WITH PERSISTENT WAA PATTERN CONTINUE TO RIDE THE
EDGE OF THE INCREASING CAP THIS AFTERNOON AND MAY CONT TO AFFECT
A SMALL PORTION OF OUR WESTERN IOWA COUNTIES FOR A COUPLE OF MORE
HOURS BEFORE THE CAPPING INVERSION BECOMES TO STRONG FOR OUR CWA.
OTHER CONVECTION WILL LIKELY GET GOING OVER THE HIGH PLAINS
ASSOCIATED WITH A LEE TROUGH WHERE TEMPERATURES HAVE SOARED INTO
THE LOWER 100S...AND LOW-LEVEL LAPSE RATES HAVE STEEPENED
SUFFICIENTLY TO ALLOW FOR CI. SOME HIGH-RES GUIDANCE INDICATES
THAT SOME OF THIS ACTIVITY MAY WANT TO TRY AND MAKE IT INTO NE NEB
LATE THIS EVENING BUT WE FEEL THIS APPEARS A BIT OVERDONE GIVEN
THE INCREASE CAP AHEAD OF THIS AREA OF DEEP MIXING. THUS IT SHOULD
BE A FAIRLY QUIET BUT WARM NIGHT WITH BREEZY SOUTH WINDS.
THE MODELS ARE IN BETTER AGREEMENT TODAY IN THE CDFNT TIMING FOR
FRI AS THE NAM HAS SLOWED THE PROGRESSION OF THE FRONT CLOSER TO
THE EC/GEM OF YESTERDAY. THUS HIGHS IN THE CNTRL/SRN CWA SHOULD
CLIMB INTO THE MID AND UPPER 90S...AND WITH DEW POINTS IN THE
LOWER TO MID 70S...WE WILL LIKELY SEE A PERIOD OF HEAT ADVISORY
CRITERIA BEING MET. THE FRONTAL BOUNDARY STILL LOOKS LIKE IT WILL
REMAIN CAPPED OVER THE FA GIVEN THE WARM MID-LEVEL TEMPERATURES
AND LACK OF LARGE-SCALE FORCING FOR ASCENT. THE COLD FRONT WILL
STALL NEAR THE KS/NEB BORDER ON FRI NIGHT WITH THE LOW-LEVEL FLOW
TURNING TO THE EAST OVERNIGHT KEEPING MOISTURE LOCKED INTO THE FA.
TSRA MAY STILL DEVELOP IN THE UPSLOPE REGIME OVER THE HIGH PLAINS
FRI AFTN AND ATTEMPT TO ROLL ALONG THE EDGE OF THE MID LEVEL
CAP/INSTABILITY GRADIENT OVER NRN NEB/SRN SD FRI NIGHT. THE
NAM/EC ARE THE STRONGEST WITH THIS PATTERN AS THE GFS SCOURS OUT
MORE OF THE MOISTURE POST FRONTAL. CURRENTLY WE PREFER MORE THE
EC/NAM LOOK TO THE PATTERN AND WILL CONT WITH SOME POPS AFTER 09Z
FRI NIGHT. SOME CONVECTION MAY TRY AND LINGER INTO THE DAY ON SAT
OR REGENERATE GIVEN THE RESIDUAL MOISTURE AND INVERTED TROUGH
SLIDING SEWD THROUGH THE CWA. CONFIDENCE IS LOWER DURING THIS
PERIOD...BUT SYNOPTIC PATTERN DOES FAVOR SOME CONVECTION ON
SAT...EITHER A CONTINUATION OF OVERNIGHT ACTIVITY OR NEW
DEVELOPMENT ALONG THE INVERTED TROUGH DURING THE AFTN. EFFECTIVE
SHEAR AND INSTABILITY WOULD SUPPORT AN ISO SVR THREAT IF THIS
PATTERN ENDS UP DEVELOPING. ONCE THE INVERTED TROUGH MOVES THROUGH
THE SOUTHERN CWA ON SAT EVENING THE CONVECTIVE CHANCES LOOK TO END
FOR THE REST OF THE SHORT TERM WITH MUCH COOLER AND DRIER AIR
MOVS INTO THE AREA FOR SUNDAY.
.LONG TERM...(SUNDAY NIGHT THROUGH THURSDAY)
ISSUED AT 316 PM CDT THU JUL 24 2014
MOST OF THE EXTENDED PERIOD STILL APPEARS QUIET WITH SEASONABLY
COOL AIR IN PLACE WITH NORTHWEST FLOW ALOFT. HIGHS IN THE UPPER
70S TO LOWER 80S APPEAR LIKELY FOR MON/TUE BEFORE TEMPERATURES
START TO SLOWLY MODERATE TOWARD NORMAL. AS RETURN FLOW DEVELOPS BY
MID WEEK WE WILL CONT TO MENTION THE CHANCES FOR MAINLY NOCTURNAL
SHOWERS AND THUNDERSTORMS TO END THE PERIOD.
&&
.AVIATION...(06Z TAFS FOR KOFK...KLNK AND KOMA.)
ISSUED AT 1130 PM CDT THU JUL 24 2014
WINDS WILL CONTINUE TO GRADUALLY VEER TONIGHT THROUGH FRIDAY.
INITIALLY...WINDS WILL BE SOUTHEAST AT 12 TO 15 KNOTS...WITH
GUSTS UP TO 20 TO 25 KNOTS...BECOMING SOUTHWEST AND EVENTUALLY
NORTHWEST THROUGH THE PERIOD. A FEW SHOWERS AND THUNDERSTORMS WILL
ALSO BE POSSIBLE BETWEEN 6-8Z AT KOFK AND 7-09Z AT KLNK AND 8-10Z
AT KOMA. BUT ANY STORMS THAT DO MAKE THEIR WAY TO THOSE SITES ARE
EXPECTED TO BE FAIRLY SHORT LIVED.
&&
.OAX WATCHES/WARNINGS/ADVISORIES...
NE...HEAT ADVISORY FROM NOON TO 7 PM CDT FRIDAY FOR NEZ065>068-078-
088>093.
IA...HEAT ADVISORY FROM NOON TO 7 PM CDT FRIDAY FOR IAZ079-080-090-
091.
&&
$$
UPDATE...DEWALD
SHORT TERM...BOUSTEAD
LONG TERM...BOUSTEAD
AVIATION...DEWALD/GROSS
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
100 PM EDT FRI JUL 25 2014
.SYNOPSIS...
A STALLED FRONT WILL BECOME INTERTWINED WITH THE SEABREEZE TODAY.
THE FRONT WILL LIFT NORTH AND DISSIPATE TONIGHT. HIGH PRESSURE WILL
FOLLOW AND BRING HOT...HUMID AND SULTRY CONDITIONS THIS WEEKEND AND
ON MONDAY. THE NEXT COLD FRONT WILL DROP ACROSS THE AREA TUESDAY. IN
ITS WAKE...COOLER AND DRIER CONDITIONS WILL OVERSPREAD THE AREA FOR
THE MIDDLE OF NEXT WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 100 PM FRIDAY...THICK CLOUDS HAVE STUBBORNLY HELD ON NORTH OF
THE STALLED FRONT. THIS OBVIOUSLY HAS HAD IMPACTS ON TEMPERATURES
AND ALSO WIND DIRECTIONS AS THERE IS NO SEABREEZE CIRCULATION TO
SPEAK OF YET. HIGHS HAVE BEEN ADJUSTED DOWNWARD BY ANOTHER 1-2
DEGREES IN MOST AREAS...WITH AIR TEMPERATURES NOW EXPECTED TO REMAIN
BELOW OCEAN WATER TEMPERATURES AT BEACHES TODAY. (HOW OFTEN DOES
THAT HAPPEN IN JULY?)
CONVECTION HAS BEGUN DEVELOPING ALONG THE FRONT ACROSS WILLIAMSBURG
AND GEORGETOWN COUNTIES IN SC. FORECAST POPS NEAR THE SANTEE RIVER
ARE 60-80 PERCENT WITH AROUND HALF AN INCH OF AREAL RAINFALL TOTALS
EXPECTED. ISOLATED SPOTS WILL UNDOUBTEDLY PICK UP 2-3 INCHES ON ONE
SIDE OR OTHER OF THE SANTEE RIVER. PREVIOUS DISCUSSION FROM 1000 AM
FOLLOWS...
THE COLD FRONT HAS PUSHED SURPRISINGLY FAR TO THE SOUTH AND IS
EASILY VISIBLE ON SATELLITE IMAGERY AS A WALL OF LOW STRATUS AND
EVEN SOME PATCHY FOG. THIS BOUNDARY HAS PUSHED INTO MYRTLE
BEACH...CONWAY...AND KINGSTREE SC IN THE PAST HOUR AND SHOULD STALL
SHORTLY IN THE VICINITY OF PAWLEYS ISLAND...ANDREWS AND GREELEYVILLE
SC. MODELS SHOW THIS FRONT RETURNING NORTHWARD THIS AFTERNOON AS
HIGH PRESSURE MOVES OFF THE MID-ATLANTIC COAST...ALSO HELPED BY A
WEAK SEABREEZE CIRCULATION THAT SHOULD ADD SOME NORTHBOUND MOMENTUM
TO OUR LOW-LEVEL WINDS.
DIFFERENTIAL HEATING ALONG THE FRONT SHOULD HELP INTENSIFY LOW-LEVEL
CONVERGENCE BY EARLY AFTERNOON...AND THE LATEST FEW HRRR MODEL RUNS
PLUS LAST NIGHT`S NSSL WRF SHOW THUNDERSTORMS INITIATING ACROSS
GEORGETOWN AND HORRY COUNTIES EARLY THIS AFTERNOON. ALTHOUGH CELL
MOTION SHOULD BE EASTWARD AT 10-15 MPH...STORMS WILL INGEST THE
DRIER AIR ALOFT IN DOWNDRAFTS CREATING A COMPLEX NETWORK OF
BOUNDARIES THAT WILL ULTIMATELY DETERMINE STORM MOTION AND FUTURE
DEVELOPMENT. MY HIGHEST POPS (60-70 PERCENT) ARE CENTERED ACROSS
SOUTHERN HORRY COUNTY...WITH LOWER POPS (30-50 PERCENT) EXTENDING
INTO THE NORTHERN PEE DEE REGION AND SE NORTH CAROLINA.
WATER VAPOR IMAGERY SHOWS THE MID LEVELS HAVE DRIED SINCE YESTERDAY
EVENING. THE 12Z MHX SOUNDING WAS DOWN TO 1.75 INCHES PRECIPITABLE
WATER WITH AROUND 1.9 INCHES ON THE CHS SOUNDING. THE BULK OF THIS
DRYING IS ABOVE THE 700 MB LAYER. 0-6 KM BULK SHEAR HAS DECREASED
FROM YESTERDAY AS HAS OVERALL INSTABILITY VALUES WHICH ARE
ANTICIPATED TO AVERAGE 1500-2500 J/KG TODAY VERSUS 3000-4000 J/KG
YESTERDAY.
I HAVE BUMPED DOWN TEMPERATURES BY A COUPLE DEGREES WHERE CLOUDS
THIS MORNING PLUS ONSHORE WINDS THIS AFTERNOON WILL HELP HOLD DOWN
HEATING. OTHERWISE NO SIGNIFICANT CHANGES ARE PLANNED.
&&
.SHORT TERM /SATURDAY THROUGH SUNDAY NIGHT/...
AS OF 330 AM FRIDAY...MODELS CONTINUE WITH THE ONGOING LONGWAVE
UPPER PATTERN THIS PERIOD...WITH TROFFING ALOFT ACROSS THE
EASTERN 1/3RD OF THE U.S. AND RIDGING ALOFT FOR THE WESTERN 2/3RDS
OF THE U.S. THE UPPER TROF AXIS...NOT AS AMPLIFIED AS WAS EARLIER
IN THE WEEK...IS PROGGED TO A POSITION JUST OFF THE CAROLINA
COASTS...BASICALLY ALONG THE EASTERN SEABOARD. AT THE SFC...MODELS
INDICATE THE SFC FRONT WILL DECAY ACROSS THE AREA ON SATURDAY.
THIS WILL LEAVE THE FA UNDER WEAK RIDGING FROM THE ATL
WATERS...AND THE FORMATION OF THE PIEDMONT TROF ACROSS THE CENTRAL
CAROLINAS DURING SATURDAY.
FOR SUNDAY THRU SUNDAY NIGHT...THE MODELS REMAIN IN GOOD
AGREEMENT WITH THE AMPLIFICATION OF BOTH THE UPPER TROF
OVERHEAD...AND THE UPPER RIDGING THAT IS CURRENTLY AFFECTING THE
WESTERN 2/3RDS OF THE U.S. A S/W TROF IS PROGGED TO DIVE OUT OF
CENTRAL CANADA EARLY SUNDAY...AND BASICALLY AID IN THE
AMPLIFICATION PROCESS OF THE FLOW ALOFT ACROSS THE CONTERMINOUS
U.S. AT THE SFC...THE WEAK RIDGING FROM OFF THE COAST WILL GET
SHUNTED SOUTH OF THE AREA. THE PIEDMONT SFC TROF WILL GAIN SOME
STRENGTH AS MODELS CONTINUE WITH THE TIGHTENING OF THE GRADIENT
ASSOCIATED WITH THE PIEDMONT TROF.
THIS PERIOD WILL BE HIGHLIGHTED BY THE 3HS...HAZY HOT AND HUMID.
VERY LITTLE IN THE WAY OF CONVECTION IS EXPECTED EXCEPT FOR ISOLATED
CHANCES ALONG THE SEA BREEZE BOUNDARY...AND ANY CONVECTION THAT
DRIFTS TO THE FA AFTER FIRING UP ALONG THE PIEDMONT TROF. THUS
20-30 POPS ARE THE HIGHEST WILL GO THIS PERIOD. OVERALL...WARMER
TEMPS ALOFT AS WELL AS SUBSIDENCE ALOFT...WILL BOTH AID IN KEEPING
A LID ON CONVECTION THIS WEEKEND. VARIOUS MODEL MOS GUIDANCE DOES
PAINT WIDESPREAD 90+ DEGREE TEMPS FOR SATURDAY...AND EVEN HOTTER
ON SUNDAY. HAVE GONE ALONG WITH THESE NUMBERS ESPECIALLY WITH THE
DECENT W-NW DOWNSLOPE FLOW ALOFT. IN FACT...HEAT ADVISORY CRITERIA
WILL LIKELY BE MET ON SUNDAY WITH HIGHS WELL INTO THE 90S ALONG
WITH HUMIDITY LEVELS HAVING INCHED BACK UPWARDS. THUS THE 2
COMBINED PROVIDE FORECAST HEAT INDICES REACHING A WIDESPREAD
104-106 DEGREES ACROSS THE FA.
&&
.LONG TERM /MONDAY THROUGH THURSDAY/...
AS OF 300 PM THURSDAY...MID LEVEL TROUGH WILL DOMINATE MUCH OF THE
PERIOD KEEPING TEMPERATURES ACROSS THE REGION BELOW CLIMO. THE
EXCEPTION WILL BE ON SUN WITH MID LEVEL RIDGE TO THE WEST
EXTENDING EAST. 850 TEMPS WILL FLIRT WITH 20-22C WHICH SHOULD
PRODUCE HIGHS IN THE MID TO UPPER 90S. DESPITE THE HOT TEMPS DO NOT
THINK THERE WILL BE MUCH CONVECTION AROUND. WESTERLY MID LEVEL FLOW
AND SUBSIDENCE ON THE RIDGES PERIPHERY WILL KEEP MID LEVELS DRY.
CANNOT RULE OUT ISOLATED CONVECTION...ESPECIALLY LATER IN THE DAY
ASSOCIATED WITH THE PIEDMONT TROUGH BUT SEE NO REASON TO GO ABOVE
INHERITED SILENT POP.
COLD FRONT MOVES INTO THE AREA LATE MON...PUSHED BY IMPRESSIVE MID
LEVEL TROUGH. DOES NOT LOOK LIKE MON WILL BE AS HOT AS SUN GIVEN
INCREASED MID LEVEL MOISTURE AND MORE WIDESPREAD CONVECTION LATER IN
THE DAY...JUST AHEAD OF THE FRONT. SHOULD THE FRONT BE DELAYED A BIT
MON COULD END UP AS HOT AS SUN GIVEN 850 TEMPS HANGING IN THE LOW
20C RANGE FOR MUCH OF THE DAY. LATER MON INTO TUE WILL BE THE MOST
ACTIVE PART OF THE PERIOD CONVECTIVELY SPEAKING AND WILL MAINTAIN
INHERITED HIGH CHC POP.
MID LEVEL TROUGH AXIS WILL REMAIN WEST OF THE AREA THROUGH THE
PERIOD WITH THE FRONT STALLING NOT TOO FAR OFF THE COAST. INITIALLY
MID LEVELS ARE DRY BUT INCREASING MOISTURE ALOFT WILL RESULT IN A
SLOW INCREASE IN POP THROUGH THE MIDDLE OF NEXT WEEK. TEMPS WILL RUN
A LITTLE BELOW CLIMO LATE IN THE PERIOD.
&&
.AVIATION /12Z FRIDAY THROUGH WEDNESDAY/...
AS OF 18Z...EXPECT VFR THROUGH THIS EVENING WITH INCREASING CHANCES
FOR SHRA/TSRA THROUGH THIS AFTERNOON...ESPECIALLY NEAR & SOUTH OF
MYRTLE BEACH. MVFR/IFR POSSIBLE LATE OVERNIGHT INTO THE EARLY
MORNING HOURS DUE TO FOG/LOW CIGS...IMPROVING TO VFR SATURDAY LATE
MORNING.
MVFR/IFR CIGS HAVE PERSISTED ACROSS THE AREA..AND MAY CONTINUE TO DO
SO AT A FEW OF THE TAF SITES FOR THE NEXT HOUR BEFORE IMPROVING TO
MVFR AND THEN VFR AS THE CLOUD LAYER BURNS OFF. NORTHEAST WINDS WILL
BECOME SOUTHEAST ALONG THE COAST AROUND 10 KTS LATER THIS AFTERNOON
WITH INLAND SITES CONTINUING A LIGHT NORTHEAST WIND. LATEST RADAR
IMAGERY DEPICTS INCREASING SHRA/TSRA NEAR GEORGETOWN AND CHARLESTON
SC...AND COVERAGE AND CHANCES WILL INCREASE THROUGHOUT THE REST OF
THE AFTERNOON AS THE SEA BREEZE AND THE FRONT INTERACT. ANY
SHRA/TSRA COULD PRODUCE HEAVY RAINFALL OR FLIGHT CAT
RESTRICTIONS...AND WILL TAPER OFF LATER THIS EVENING. OVERNIGHT INTO
THE EARLY MORNING HOURS WINDS WILL BECOME LIGHT AND VARIABLE AND
MVFR/IFR IS POSSIBLE DUE TO FOG AT ALL SITES...WHICH WILL DISSIPATE
SATURDAY MORNING GIVING WAY TO VFR WITH LIGHT WINDS.
EXTENDED OUTLOOK...SHOWERS/TSTMS/TEMPO MVFR POSSIBLE SUNDAY AND
MONDAY. OTHERWISE EXPECT VFR.
&&
.MARINE...
NEAR TERM /THROUGH TONIGHT/...
AS OF 100 PM FRIDAY...LATEST MODELS AND OBSERVATIONS INDICATE
PERHAPS EVEN A SLOWER RETURN NORTHWARD FOR THE FRONT...MAINLY
BECAUSE THICK CLOUD COVER INLAND HAS REDUCED THE RATE TEMPERATURES
ARE RISING WHICH HAS VIRTUALLY ELIMINATED ANY SEABREEZE WINDS SO
FAR. NORTH OF WINYAH BAY NE WINDS SHOULD BECOME EASTERLY IN A FEW
HOURS...THEN WILL VEER MORE SOUTHERLY TONIGHT AS THE FRONT STARTS TO
MOVE NORTHWARD. MARINERS SHOULD BEWARE FOR INCREASING SHOWER AND
T-STORM COVERAGE IN THE GEORGETOWN/MURRELLS INLET VICINITY THIS
AFTERNOON. PREVIOUS DISCUSSION FROM 1000 AM FOLLOWS...
THE COLD FRONT HAS PUSHED ALL THE WAY DOWN TO MYRTLE BEACH THIS
MORNING WITH NORTH WINDS GUSTING AS HIGH AS 15 KNOTS ACROSS THE
WATERS OF SOUTHEASTERN NORTH CAROLINA. THE FRONT SHOULD STALL SOON
NEAR MURRELLS INLET OR PAWLEYS ISLAND...THEN WILL RETURN NORTHWARD
THIS AFTERNOON. THE BIGGEST CHANGE TO THE FORECAST REGARDS WIND
DIRECTION THIS MORNING WHICH ARE MAINLY NORTH TO NORTHEAST BEHIND
THE FRONT...BUT REMAIN SOUTHWESTERLY ACROSS THE GEORGETOWN COUNTY
WATERS. LATEST MODELS SHOW A SLOWER VEERING OF THE SURFACE WINDS
NORTH OF THE FRONT THIS AFTERNOON...WITH DIRECTIONS REMAINING EAST
FOR A LONGER PERIOD OF TIME THAN EARLIER THOUGH. FORTUNATELY WIND
SPEEDS SHOULD REMAIN FAIRLY LIGHT.
SEAS ARE RUNNING 2-3 FT CURRENTLY...AND WITH NO SIGNIFICANT INCREASE
EXPECTED IN WIND SPEEDS THROUGH THE DAY I HAVE TRIMMED ABOUT A FOOT
OFF THE PREVIOUS FORECAST. A 9-SECOND SOUTHEAST SWELL CONTINUES.
SHORT TERM /SATURDAY THROUGH SUNDAY NIGHT/...
AS OF 330 AM FRIDAY...FOR SATURDAY...THE AREA WATERS WILL BE
UNDER THE INFLUENCE OF A DECAYING FRONTAL BOUNDARY...RESULTING IN
MAINLY A VARIABLE WIND DIRECTION FOR MUCH OF THE DAY...AND WITH
THE LACK OF ANY GRADIENT...SPEEDS WILL GENERALLY BE 10 KT OR LESS.
FOR SUNDAY...THE AMPLIFYING FLOW ALOFT WILL RESULT IN A
STRENGTHENING SFC PIEDMONT TROF ACROSS THE CENTRAL CAROLINAS AND
THE RIDGING FROM THE BERMUDA HIGH BEING SHUNTED WELL SOUTH OF THE
AREA WATERS. THIS WILL PRODUCE A TIGHTENING SFC PG ACROSS THE
CAROLINAS INCLUDING THE COASTAL WATERS. THE SFC PRESSURE PATTERN
WILL YIELD A SFC SW-WSW WIND DIRECTION...WITH INCREASING SPEEDS
SUNDAY INTO SUNDAY NIGHT. SCEC AND/OR SCA CONDITIONS WILL LIKELY
BE MET SUNDAY AFTERNOON AND/OR NIGHT.
SIGNIFICANT SEAS WILL BE AT THEIR EBB DURING SATURDAY WITH AN ESE-
SE 1-3 FOOT GROUND SWELL DOMINATING THE WATERS. THE AFTN/EVENING SEA
BREEZE CIRCULATION WILL ADD SOME WIND CHOP NEAR SHORE. FOR
SUNDAY...LOOK FOR WIND DRIVEN WAVES TO STEADILY INCREASE IN BOTH
HEIGHT AND PERIODS...AND WILL LIKELY BE THE DOMINANT PLAYER IN THE
SIGNIFICANT SEAS FORMULA. WILL ADVERTISE 6 FOOTERS ACROSS THE
LOCAL WATERS LATE SUNDAY AFTERNOON BUT MORE LIKE SUNDAY NIGHT.
.LONG TERM /MONDAY THROUGH TUESDAY/...
AS OF 300 PM THURSDAY...MODEST SW FLOW ON SUN WILL INCREASE INTO MON
AS GRADIENT TIGHTENS AHEAD OF ADVANCING COLD FRONT. SPEEDS LATER SUN
MAY APPROACH SCEC THRESHOLDS AS PIEDMONT TROUGH STRENGTHENS. SCA
HEADLINES SEEM CERTAIN FOR AT LEAST MON AND POSSIBLY SUN NIGHT AS
PROLONGED STRONG SOUTHWEST FLOW BUILDS SEAS TO 4 TO 6 FT. FRONT
MOVES ACROSS THE WATERS MON NIGHT WITH NORTHERLY FLOW DEVELOPING.
GRADIENT RELAXES BEHIND THE FRONT AND SPEEDS WILL DROP UNDER 10 KT
BY MIDDAY TUE. FRONT ENDS UP STALLED JUST EAST OF THE WATERS WITH
THE PROXIMITY TO THE FRONTAL ZONE KEEPING GRADIENT WEAK AND WINDS
LIGHT AND VARIABLE. SEAS WILL DROP TO 3 TO 4 FT BEHIND THE FRONT AND
BELOW 3 FT BY THE END OF THE PERIOD.
&&
.ILM WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
NC...NONE.
MARINE...NONE.
&&
$$
NEAR TERM...TRA
SHORT TERM...DCH
LONG TERM...III
AVIATION...SGL
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
1014 AM EDT FRI JUL 25 2014
.SYNOPSIS...
A STALLED FRONT WILL BECOME INTERTWINED WITH THE SEABREEZE TODAY.
THE FRONT WILL LIFT NORTH AND DISSIPATE TONIGHT. HIGH PRESSURE WILL
FOLLOW AND BRING HOT...HUMID AND SULTRY CONDITIONS THIS WEEKEND AND
ON MONDAY. THE NEXT COLD FRONT WILL DROP ACROSS THE AREA TUESDAY. IN
ITS WAKE...COOLER AND DRIER CONDITIONS WILL OVERSPREAD THE AREA FOR
THE MIDDLE OF NEXT WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 1000 AM FRIDAY...THE COLD FRONT HAS PUSHED SURPRISINGLY FAR TO
THE SOUTH AND IS EASILY VISIBLE ON SATELLITE IMAGERY AS A WALL OF
LOW STRATUS AND EVEN SOME PATCHY FOG. THIS BOUNDARY HAS PUSHED INTO
MYRTLE BEACH...CONWAY...AND KINGSTREE SC IN THE PAST HOUR AND SHOULD
STALL SHORTLY IN THE VICINITY OF PAWLEYS ISLAND...ANDREWS AND
GREELEYVILLE SC. MODELS SHOW THIS FRONT RETURNING NORTHWARD THIS
AFTERNOON AS HIGH PRESSURE MOVES OFF THE MID-ATLANTIC COAST...ALSO
HELPED BY A WEAK SEABREEZE CIRCULATION THAT SHOULD ADD SOME
NORTHBOUND MOMENTUM TO OUR LOW-LEVEL WINDS.
DIFFERENTIAL HEATING ALONG THE FRONT SHOULD HELP INTENSIFY LOW-LEVEL
CONVERGENCE BY EARLY AFTERNOON...AND THE LATEST FEW HRRR MODEL RUNS
PLUS LAST NIGHT`S NSSL WRF SHOW THUNDERSTORMS INITIATING ACROSS
GEORGETOWN AND HORRY COUNTIES EARLY THIS AFTERNOON. ALTHOUGH CELL
MOTION SHOULD BE EASTWARD AT 10-15 MPH...STORMS WILL INGEST THE
DRIER AIR ALOFT IN DOWNDRAFTS CREATING A COMPLEX NETWORK OF
BOUNDARIES THAT WILL ULTIMATELY DETERMINE STORM MOTION AND FUTURE
DEVELOPMENT. MY HIGHEST POPS (60-70 PERCENT) ARE CENTERED ACROSS
SOUTHERN HORRY COUNTY...WITH LOWER POPS (30-50 PERCENT) EXTENDING
INTO THE NORTHERN PEE DEE REGION AND SE NORTH CAROLINA.
WATER VAPOR IMAGERY SHOWS THE MID LEVELS HAVE DRIED SINCE YESTERDAY
EVENING. THE 12Z MHX SOUNDING WAS DOWN TO 1.75 INCHES PRECIPITABLE
WATER WITH AROUND 1.9 INCHES ON THE CHS SOUNDING. THE BULK OF THIS
DRYING IS ABOVE THE 700 MB LAYER. 0-6 KM BULK SHEAR HAS DECREASED
FROM YESTERDAY AS HAS OVERALL INSTABILITY VALUES WHICH ARE
ANTICIPATED TO AVERAGE 1500-2500 J/KG TODAY VERSUS 3000-4000 J/KG
YESTERDAY.
I HAVE BUMPED DOWN TEMPERATURES BY A COUPLE DEGREES WHERE CLOUDS
THIS MORNING PLUS ONSHORE WINDS THIS AFTERNOON WILL HELP HOLD DOWN
HEATING. OTHERWISE NO SIGNIFICANT CHANGES ARE PLANNED.
&&
.SHORT TERM /SATURDAY THROUGH SUNDAY NIGHT/...
AS OF 330 AM FRIDAY...MODELS CONTINUE WITH THE ONGOING LONGWAVE
UPPER PATTERN THIS PERIOD...WITH TROFFING ALOFT ACROSS THE
EASTERN 1/3RD OF THE U.S. AND RIDGING ALOFT FOR THE WESTERN 2/3RDS
OF THE U.S. THE UPPER TROF AXIS...NOT AS AMPLIFIED AS WAS EARLIER
IN THE WEEK...IS PROGGED TO A POSITION JUST OFF THE CAROLINA
COASTS...BASICALLY ALONG THE EASTERN SEABOARD. AT THE SFC...MODELS
INDICATE THE SFC FRONT WILL DECAY ACROSS THE AREA ON SATURDAY.
THIS WILL LEAVE THE FA UNDER WEAK RIDGING FROM THE ATL
WATERS...AND THE FORMATION OF THE PIEDMONT TROF ACROSS THE CENTRAL
CAROLINAS DURING SATURDAY.
FOR SUNDAY THRU SUNDAY NIGHT...THE MODELS REMAIN IN GOOD
AGREEMENT WITH THE AMPLIFICATION OF BOTH THE UPPER TROF
OVERHEAD...AND THE UPPER RIDGING THAT IS CURRENTLY AFFECTING THE
WESTERN 2/3RDS OF THE U.S. A S/W TROF IS PROGGED TO DIVE OUT OF
CENTRAL CANADA EARLY SUNDAY...AND BASICALLY AID IN THE
AMPLIFICATION PROCESS OF THE FLOW ALOFT ACROSS THE CONTERMINOUS
U.S. AT THE SFC...THE WEAK RIDGING FROM OFF THE COAST WILL GET
SHUNTED SOUTH OF THE AREA. THE PIEDMONT SFC TROF WILL GAIN SOME
STRENGTH AS MODELS CONTINUE WITH THE TIGHTENING OF THE GRADIENT
ASSOCIATED WITH THE PIEDMONT TROF.
THIS PERIOD WILL BE HIGHLIGHTED BY THE 3HS...HAZY HOT AND HUMID.
VERY LITTLE IN THE WAY OF CONVECTION IS EXPECTED EXCEPT FOR ISOLATED
CHANCES ALONG THE SEA BREEZE BOUNDARY...AND ANY CONVECTION THAT
DRIFTS TO THE FA AFTER FIRING UP ALONG THE PIEDMONT TROF. THUS
20-30 POPS ARE THE HIGHEST WILL GO THIS PERIOD. OVERALL...WARMER
TEMPS ALOFT AS WELL AS SUBSIDENCE ALOFT...WILL BOTH AID IN KEEPING
A LID ON CONVECTION THIS WEEKEND. VARIOUS MODEL MOS GUIDANCE DOES
PAINT WIDESPREAD 90+ DEGREE TEMPS FOR SATURDAY...AND EVEN HOTTER
ON SUNDAY. HAVE GONE ALONG WITH THESE NUMBERS ESPECIALLY WITH THE
DECENT W-NW DOWNSLOPE FLOW ALOFT. IN FACT...HEAT ADVISORY CRITERIA
WILL LIKELY BE MET ON SUNDAY WITH HIGHS WELL INTO THE 90S ALONG
WITH HUMIDITY LEVELS HAVING INCHED BACK UPWARDS. THUS THE 2
COMBINED PROVIDE FORECAST HEAT INDICES REACHING A WIDESPREAD
104-106 DEGREES ACROSS THE FA.
&&
.LONG TERM /MONDAY THROUGH THURSDAY/...
AS OF 300 PM THURSDAY...MID LEVEL TROUGH WILL DOMINATE MUCH OF THE
PERIOD KEEPING TEMPERATURES ACROSS THE REGION BELOW CLIMO. THE
EXCEPTION WILL BE ON SUN WITH MID LEVEL RIDGE TO THE WEST
EXTENDING EAST. 850 TEMPS WILL FLIRT WITH 20-22C WHICH SHOULD
PRODUCE HIGHS IN THE MID TO UPPER 90S. DESPITE THE HOT TEMPS DO NOT
THINK THERE WILL BE MUCH CONVECTION AROUND. WESTERLY MID LEVEL FLOW
AND SUBSIDENCE ON THE RIDGES PERIPHERY WILL KEEP MID LEVELS DRY.
CANNOT RULE OUT ISOLATED CONVECTION...ESPECIALLY LATER IN THE DAY
ASSOCIATED WITH THE PIEDMONT TROUGH BUT SEE NO REASON TO GO ABOVE
INHERITED SILENT POP.
COLD FRONT MOVES INTO THE AREA LATE MON...PUSHED BY IMPRESSIVE MID
LEVEL TROUGH. DOES NOT LOOK LIKE MON WILL BE AS HOT AS SUN GIVEN
INCREASED MID LEVEL MOISTURE AND MORE WIDESPREAD CONVECTION LATER IN
THE DAY...JUST AHEAD OF THE FRONT. SHOULD THE FRONT BE DELAYED A BIT
MON COULD END UP AS HOT AS SUN GIVEN 850 TEMPS HANGING IN THE LOW
20C RANGE FOR MUCH OF THE DAY. LATER MON INTO TUE WILL BE THE MOST
ACTIVE PART OF THE PERIOD CONVECTIVELY SPEAKING AND WILL MAINTAIN
INHERITED HIGH CHC POP.
MID LEVEL TROUGH AXIS WILL REMAIN WEST OF THE AREA THROUGH THE
PERIOD WITH THE FRONT STALLING NOT TOO FAR OFF THE COAST. INITIALLY
MID LEVELS ARE DRY BUT INCREASING MOISTURE ALOFT WILL RESULT IN A
SLOW INCREASE IN POP THROUGH THE MIDDLE OF NEXT WEEK. TEMPS WILL RUN
A LITTLE BELOW CLIMO LATE IN THE PERIOD.
&&
.AVIATION /12Z FRIDAY THROUGH TUESDAY/...
AS OF 12Z...AREAS OF MVFR/IFR FOR THE NEXT HOUR OR TWO DUE TO
ADVECTION FOG AND LOW CIGS ASSOCIATED WITH A FRONTAL BOUNDARY.
CONDITIONS IMPROVE TO VFR BY LATE MORNING. SHRA/TSRA POSSIBLE THIS
AFTERNOON...ESPECIALLY ALONG THE COAST.
IFR DUE TO LOW CIGS AND FOG IS CURRENTLY BEING OBSERVED AT
KILM/KFLO/KLBT. EXPECT THIS TO IMPROVE TO MVFR AND THEN VFR
WITHIN THE NEXT COUPLE OF HOURS AND FOR NORTHERLY WINDS TO
INCREASE TO AOB 5 KTS. INTO THIS AFTERNOON...WINDS WILL BECOME
SOUTHEAST AOB 10 KTS ALONG THE COAST WHILE LIGHT WINDS REMAIN
INLAND. CHANCES WILL INCREASE FOR ISOLATED TO SCATTERED
TSRA/SHRA...ESPECIALLY ALONG THE COAST...AS THE SEA BREEZE AND
FRONTAL BOUNDARY INTERACT. ANY CONVECTION WILL TAPER OFF LATER
TONIGHT...AND OVERNIGHT INTO THE EARLY MORNING HOURS WINDS WILL
BECOME LIGHT AND VARIABLE WITH MVFR/IFR IS POSSIBLE DUE TO FOG AT
ALL SITES.
EXTENDED OUTLOOK...SHOWERS/TSTMS/TEMPO MVFR POSSIBLE SUNDAY AND
MONDAY. OTHERWISE EXPECT VFR.
&&
.MARINE...
NEAR TERM /THROUGH TONIGHT/...
AS OF 1000 AM FRIDAY...THE COLD FRONT HAS PUSHED ALL THE WAY DOWN TO
MYRTLE BEACH THIS MORNING WITH NORTH WINDS GUSTING AS HIGH AS 15
KNOTS ACROSS THE WATERS OF SOUTHEASTERN NORTH CAROLINA. THE FRONT
SHOULD STALL SOON NEAR MURRELLS INLET OR PAWLEYS ISLAND...THEN WILL
RETURN NORTHWARD THIS AFTERNOON. THE BIGGEST CHANGE TO THE FORECAST
REGARDS WIND DIRECTION THIS MORNING WHICH ARE MAINLY NORTH TO
NORTHEAST BEHIND THE FRONT...BUT REMAIN SOUTHWESTERLY ACROSS THE
GEORGETOWN COUNTY WATERS. LATEST MODELS SHOW A SLOWER VEERING OF THE
SURFACE WINDS NORTH OF THE FRONT THIS AFTERNOON...WITH DIRECTIONS
REMAINING EAST FOR A LONGER PERIOD OF TIME THAN EARLIER THOUGH.
FORTUNATELY WIND SPEEDS SHOULD REMAIN FAIRLY LIGHT.
SEAS ARE RUNNING 2-3 FT CURRENTLY...AND WITH NO SIGNIFICANT INCREASE
EXPECTED IN WIND SPEEDS THROUGH THE DAY I HAVE TRIMMED ABOUT A FOOT
OFF THE PREVIOUS FORECAST. A 9-SECOND SOUTHEAST SWELL CONTINUES.
SHORT TERM /SATURDAY THROUGH SUNDAY NIGHT/...
AS OF 330 AM FRIDAY...FOR SATURDAY...THE AREA WATERS WILL BE
UNDER THE INFLUENCE OF A DECAYING FRONTAL BOUNDARY...RESULTING IN
MAINLY A VARIABLE WIND DIRECTION FOR MUCH OF THE DAY...AND WITH
THE LACK OF ANY GRADIENT...SPEEDS WILL GENERALLY BE 10 KT OR LESS.
FOR SUNDAY...THE AMPLIFYING FLOW ALOFT WILL RESULT IN A
STRENGTHENING SFC PIEDMONT TROF ACROSS THE CENTRAL CAROLINAS AND
THE RIDGING FROM THE BERMUDA HIGH BEING SHUNTED WELL SOUTH OF THE
AREA WATERS. THIS WILL PRODUCE A TIGHTENING SFC PG ACROSS THE
CAROLINAS INCLUDING THE COASTAL WATERS. THE SFC PRESSURE PATTERN
WILL YIELD A SFC SW-WSW WIND DIRECTION...WITH INCREASING SPEEDS
SUNDAY INTO SUNDAY NIGHT. SCEC AND/OR SCA CONDITIONS WILL LIKELY
BE MET SUNDAY AFTERNOON AND/OR NIGHT.
SIGNIFICANT SEAS WILL BE AT THEIR EBB DURING SATURDAY WITH AN ESE-
SE 1-3 FOOT GROUND SWELL DOMINATING THE WATERS. THE AFTN/EVENING SEA
BREEZE CIRCULATION WILL ADD SOME WIND CHOP NEAR SHORE. FOR
SUNDAY...LOOK FOR WIND DRIVEN WAVES TO STEADILY INCREASE IN BOTH
HEIGHT AND PERIODS...AND WILL LIKELY BE THE DOMINANT PLAYER IN THE
SIGNIFICANT SEAS FORMULA. WILL ADVERTISE 6 FOOTERS ACROSS THE
LOCAL WATERS LATE SUNDAY AFTERNOON BUT MORE LIKE SUNDAY NIGHT.
.LONG TERM /MONDAY THROUGH TUESDAY/...
AS OF 300 PM THURSDAY...MODEST SW FLOW ON SUN WILL INCREASE INTO MON
AS GRADIENT TIGHTENS AHEAD OF ADVANCING COLD FRONT. SPEEDS LATER SUN
MAY APPROACH SCEC THRESHOLDS AS PIEDMONT TROUGH STRENGTHENS. SCA
HEADLINES SEEM CERTAIN FOR AT LEAST MON AND POSSIBLY SUN NIGHT AS
PROLONGED STRONG SOUTHWEST FLOW BUILDS SEAS TO 4 TO 6 FT. FRONT
MOVES ACROSS THE WATERS MON NIGHT WITH NORTHERLY FLOW DEVELOPING.
GRADIENT RELAXES BEHIND THE FRONT AND SPEEDS WILL DROP UNDER 10 KT
BY MIDDAY TUE. FRONT ENDS UP STALLED JUST EAST OF THE WATERS WITH
THE PROXIMITY TO THE FRONTAL ZONE KEEPING GRADIENT WEAK AND WINDS
LIGHT AND VARIABLE. SEAS WILL DROP TO 3 TO 4 FT BEHIND THE FRONT AND
BELOW 3 FT BY THE END OF THE PERIOD.
&&
.ILM WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
NC...NONE.
MARINE...NONE.
&&
$$
NEAR TERM...TRA
SHORT TERM...DCH
LONG TERM...III
AVIATION...SGL
AREA FORECAST DISCUSSION
NWS BISMARCK ND
1237 PM CDT FRI JUL 25 2014
.UPDATE...
ISSUED AT 1237 PM CDT FRI JUL 25 2014
CLOUDS WERE MOVING OUT OF THE JAMES RIVER VALLEY AND SUNNY SKIES
ARE EXPECTED ACROSS WESTERN AND CENTRAL NORTH DAKOTA THIS
AFTERNOON. CURRENT FORECAST ON TRACK FOR THE AFTERNOON.
UPDATE ISSUED AT 938 AM CDT FRI JUL 25 2014
AREA OF LOW CLOUDS REMAINED ALONG OR EAST OF
CARRINGTON/BISMARCK/LINTON/FORT YATES LINE...AND THIS CLOUD SHIELD
SHOULD CONTINUE MOVING EAST AND/OR ERODING FROM THE WEST AS DRY
HIGH PRESSURE PUSHES INTO THE REGION WITH WEST/NORTHWEST WINDS.
REST OF FORECAST FOR TODAY ON TRACK.
UPDATE ISSUED AT 636 AM CDT FRI JUL 25 2014
NARROW BAND OF CLOUDS REMAIN ACROSS CENTRAL NORTH DAKOTA AND THESE
HAVE BEEN ERODING THROUGH THE MORNING. SKIES WILL CONTINUE TO
CLEAR ACROSS THE REGION. KEPT ISOLATED SHOWERS SOUTH CENTRAL FOR A
FEW HOURS.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 335 AM CDT FRI JUL 25 2014
THE LATEST SURFACE ANALYSIS PLACES A COLD FRONT FROM NEAR SHERWOOD
TO JUST EAST OF MINOT AND SOUTH TO NEAR LINTON. WEAK PRESSURE
FALLS CONTINUE AHEAD OF THE FRONT WITH AN AREA OF SHOWERS AND
ISOLATED THUNDERSTORMS MOSTLY OVER NORTH CENTRAL NORTH DAKOTA.
THE FOG/STRATUS LOOP INDICATES POCKETS OF LOWER CLOUDS BEHIND THE
FRONT BUT STEADILY MOVING EAST. THE HRRR CEILING FORECAST HAS A
GOOD HANDLE ON THE CURRENT SITUATION AND ALSO PROGRESSIVELY MOVES
THE BACK EDGE OF THE LOWER CLOUDS THROUGH THE JAMES RIVER VALLEY
BY 14Z. WATER VAPOR IMAGERY LOOP SHOWS AN UPPER LOW SPINNING OVER
SOUTHEASTERN ALBERTA WITH A DRIER WESTERLY FLOW INTO NORTH DAKOTA.
ALBEIT A FEW DISTURBANCES ARE EMBEDDED WITHIN THE FLOW BUT THESE
ARE NOT EXPECTED TO HAVE MUCH OF AN IMPACT DURING THE SHORT TERM
PERIOD. THUS EXPECT A MOSTLY SUNNY SKY WITH BREEZY CONDITIONS AS
WESTERLY WINDS WILL RANGE BETWEEN 15 AND 25 MPH. HIGHS TODAY WILL
RANGE FROM THE UPPER 70S NORTH TO LOWER 80S SOUTH. AN AREA OF
SHOWERS WILL DEVELOP OVER SOUTH DAKOTA TONIGHT AND REMAIN SOUTH OF
NORTH DAKOTA/SOUTH DAKOTA BORDER. LATE FRIDAY NIGHT THERE WILL
ALSO BE AN AREA OF SHOWERS SLIDING INTO SOUTHERN SASKATCHEWAN AND
MANITOBA...BUT THESE SHOWERS WILL REMAIN NORTH OF THE BORDER
THROUGH 12Z SATURDAY. THUS DRY CONDITIONS WILL PREVAIL THROUGH
FRIDAY NIGHT. OVERNIGHT LOWS FRIDAY NIGHT WILL BE IN THE 50S.
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 335 AM CDT FRI JUL 25 2014
THE MAIN FEATURE OF THIS FORECAST PERIOD WILL BE THE UPPER LEVEL
LOW FORECAST BY MODELS TO MOVE SOUTHEAST FROM SASK THROUGH
MINNESOTA EVENTUALLY MERGING WITH A LONGWAVE TROUGH OVER THE
EASTERN US. AS THIS PROCESS TAKES PLACE THE LOW WILL USHER IN
COOLER SURFACE TEMPERATURES AND MORE STABLE AIR. SCATTERED SHOWERS
AND POSSIBLE AN ISOLATED THUNDERSTORM ARE FORECAST FOR THE NORTH
AND EAST ON SATURDAY. SUNDAY THROUGH TUESDAY WILL BE DRY AND
COOLER WITH HIGHS AS COOL AS THE UPPER 60S ACROSS THE TURTLE
MOUNTAINS SUNDAY...AND 70S SOUTH AND WEST. EVENTUALLY A HIGH
AMPLITUDE FLOW DEVELOPS ACROSS NORTH AMERICA WITH A LONGWAVE
TROUGH OVER THE EASTERN US AND A RIDGE OVER THE WEST BY THE MIDDLE
OF NEXT WEEK. THIS LEAVES THE NORTHERN PLAINS IN A SLIGHTLY
ANTICYCLONIC NORTHWEST FLOW REGIME THAT SHOULD SUPPRESS MUCH OF
THE CONVECTION WEDNESDAY AND THURSDAY WITH JUST ISOLATED
THUNDERSTORMS.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON)
ISSUED AT 1237 PM CDT FRI JUL 25 2014
MVFR/VFR CIGS MOVING OUT OF THE KJMS AREA AND WILL KEEP MENTION OF
CIGS OUT AT 18Z. OTHERWISE SKC WILL DOMINATE THE TERMINALS THROUGH
AT LEAST 06Z...WHEN NORTHERN TAF SITES OF KISN/KMOT MAY BE IMPACTED
BY SCATTERED CLOUDS OF VFR HEIGHT...BECOMING BROKEN AROUND 13Z-14Z.
WESTERLY WINDS GUSTING UP TO 25KT WILL SUBSIDE BY 02Z
SATURDAY...THEN WINDS INCREASE AGAIN AFT 12Z SATURDAY WITH GUSTS
SATURDAY AFTERNOON OVER 25 KNOTS.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...JV
SHORT TERM...KS
LONG TERM...WAA
AVIATION...JV
AREA FORECAST DISCUSSION
NWS BISMARCK ND
938 AM CDT FRI JUL 25 2014
.UPDATE...
ISSUED AT 938 AM CDT FRI JUL 25 2014
AREA OF LOW CLOUDS REMAINED ALONG OR EAST OF
CARRINGTON/BISMARCK/LINTON/FORT YATES LINE...AND THIS CLOUD SHIELD
SHOULD CONTINUE MOVING EAST AND/OR ERODING FROM THE WEST AS DRY
HIGH PRESSURE PUSHES INTO THE REGION WITH WEST/NORTHWEST WINDS.
REST OF FORECAST FOR TODAY ON TRACK.
UPDATE ISSUED AT 636 AM CDT FRI JUL 25 2014
NARROW BAND OF CLOUDS REMAIN ACROSS CENTRAL NORTH DAKOTA AND THESE
HAVE BEEN ERODING THROUGH THE MORNING. SKIES WILL CONTINUE TO
CLEAR ACROSS THE REGION. KEPT ISOLATED SHOWERS SOUTH CENTRAL FOR A
FEW HOURS.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 335 AM CDT FRI JUL 25 2014
THE LATEST SURFACE ANALYSIS PLACES A COLD FRONT FROM NEAR SHERWOOD
TO JUST EAST OF MINOT AND SOUTH TO NEAR LINTON. WEAK PRESSURE
FALLS CONTINUE AHEAD OF THE FRONT WITH AN AREA OF SHOWERS AND
ISOLATED THUNDERSTORMS MOSTLY OVER NORTH CENTRAL NORTH DAKOTA.
THE FOG/STRATUS LOOP INDICATES POCKETS OF LOWER CLOUDS BEHIND THE
FRONT BUT STEADILY MOVING EAST. THE HRRR CEILING FORECAST HAS A
GOOD HANDLE ON THE CURRENT SITUATION AND ALSO PROGRESSIVELY MOVES
THE BACK EDGE OF THE LOWER CLOUDS THROUGH THE JAMES RIVER VALLEY
BY 14Z. WATER VAPOR IMAGERY LOOP SHOWS AN UPPER LOW SPINNING OVER
SOUTHEASTERN ALBERTA WITH A DRIER WESTERLY FLOW INTO NORTH DAKOTA.
ALBEIT A FEW DISTURBANCES ARE EMBEDDED WITHIN THE FLOW BUT THESE
ARE NOT EXPECTED TO HAVE MUCH OF AN IMPACT DURING THE SHORT TERM
PERIOD. THUS EXPECT A MOSTLY SUNNY SKY WITH BREEZY CONDITIONS AS
WESTERLY WINDS WILL RANGE BETWEEN 15 AND 25 MPH. HIGHS TODAY WILL
RANGE FROM THE UPPER 70S NORTH TO LOWER 80S SOUTH. AN AREA OF
SHOWERS WILL DEVELOP OVER SOUTH DAKOTA TONIGHT AND REMAIN SOUTH OF
NORTH DAKOTA/SOUTH DAKOTA BORDER. LATE FRIDAY NIGHT THERE WILL
ALSO BE AN AREA OF SHOWERS SLIDING INTO SOUTHERN SASKATCHEWAN AND
MANITOBA...BUT THESE SHOWERS WILL REMAIN NORTH OF THE BORDER
THROUGH 12Z SATURDAY. THUS DRY CONDITIONS WILL PREVAIL THROUGH
FRIDAY NIGHT. OVERNIGHT LOWS FRIDAY NIGHT WILL BE IN THE 50S.
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 335 AM CDT FRI JUL 25 2014
THE MAIN FEATURE OF THIS FORECAST PERIOD WILL BE THE UPPER LEVEL
LOW FORECAST BY MODELS TO MOVE SOUTHEAST FROM SASK THROUGH
MINNESOTA EVENTUALLY MERGING WITH A LONGWAVE TROUGH OVER THE
EASTERN US. AS THIS PROCESS TAKES PLACE THE LOW WILL USHER IN
COOLER SURFACE TEMPERATURES AND MORE STABLE AIR. SCATTERED SHOWERS
AND POSSIBLE AN ISOLATED THUNDERSTORM ARE FORECAST FOR THE NORTH
AND EAST ON SATURDAY. SUNDAY THROUGH TUESDAY WILL BE DRY AND
COOLER WITH HIGHS AS COOL AS THE UPPER 60S ACROSS THE TURTLE
MOUNTAINS SUNDAY...AND 70S SOUTH AND WEST. EVENTUALLY A HIGH
AMPLITUDE FLOW DEVELOPS ACROSS NORTH AMERICA WITH A LONGWAVE
TROUGH OVER THE EASTERN US AND A RIDGE OVER THE WEST BY THE MIDDLE
OF NEXT WEEK. THIS LEAVES THE NORTHERN PLAINS IN A SLIGHTLY
ANTICYCLONIC NORTHWEST FLOW REGIME THAT SHOULD SUPPRESS MUCH OF
THE CONVECTION WEDNESDAY AND THURSDAY WITH JUST ISOLATED
THUNDERSTORMS.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SATURDAY MORNING)
ISSUED AT 636 AM CDT FRI JUL 25 2014
A NARROW LINE OF LOW VFR/MVFR CIGS WILL HOVER FROM KMOT TO KBIS
THROUGH 13Z FRIDAY...AND OVER KJMS UNTIL 16Z FRIDAY. OTHERWISE SKC
WILL DOMINATE THE TERMINALS THROUGH THE TAF PERIOD. WESTERLY WINDS
GUSTING TO 25KT WILL SUBSIDE BY 02Z SATURDAY.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...JV
SHORT TERM...KS
LONG TERM...WAA
AVIATION...WAA
AREA FORECAST DISCUSSION
NWS BISMARCK ND
640 AM CDT FRI JUL 25 2014
.UPDATE...
ISSUED AT 636 AM CDT FRI JUL 25 2014
NARROW BAND OF CLOUDS REMAIN ACROSS CENTRAL NORTH DAKOTA AND THESE
HAVE BEEN ERODING THROUGH THE MORNING. SKIES WILL CONTINUE TO
CLEAR ACROSS THE REGION. KEPT ISOLATED SHOWERS SOUTH CENTRAL FOR A
FEW HOURS.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 335 AM CDT FRI JUL 25 2014
THE LATEST SURFACE ANALYSIS PLACES A COLD FRONT FROM NEAR SHERWOOD
TO JUST EAST OF MINOT AND SOUTH TO NEAR LINTON. WEAK PRESSURE
FALLS CONTINUE AHEAD OF THE FRONT WITH AN AREA OF SHOWERS AND
ISOLATED THUNDERSTORMS MOSTLY OVER NORTH CENTRAL NORTH DAKOTA.
THE FOG/STRATUS LOOP INDICATES POCKETS OF LOWER CLOUDS BEHIND THE
FRONT BUT STEADILY MOVING EAST. THE HRRR CEILING FORECAST HAS A
GOOD HANDLE ON THE CURRENT SITUATION AND ALSO PROGRESSIVELY MOVES
THE BACK EDGE OF THE LOWER CLOUDS THROUGH THE JAMES RIVER VALLEY
BY 14Z. WATER VAPOR IMAGERY LOOP SHOWS AN UPPER LOW SPINNING OVER
SOUTHEASTERN ALBERTA WITH A DRIER WESTERLY FLOW INTO NORTH DAKOTA.
ALBEIT A FEW DISTURBANCES ARE EMBEDDED WITHIN THE FLOW BUT THESE
ARE NOT EXPECTED TO HAVE MUCH OF AN IMPACT DURING THE SHORT TERM
PERIOD. THUS EXPECT A MOSTLY SUNNY SKY WITH BREEZY CONDITIONS AS
WESTERLY WINDS WILL RANGE BETWEEN 15 AND 25 MPH. HIGHS TODAY WILL
RANGE FROM THE UPPER 70S NORTH TO LOWER 80S SOUTH. AN AREA OF
SHOWERS WILL DEVELOP OVER SOUTH DAKOTA TONIGHT AND REMAIN SOUTH OF
NORTH DAKOTA/SOUTH DAKOTA BORDER. LATE FRIDAY NIGHT THERE WILL
ALSO BE AN AREA OF SHOWERS SLIDING INTO SOUTHERN SASKATCHEWAN AND
MANITOBA...BUT THESE SHOWERS WILL REMAIN NORTH OF THE BORDER
THROUGH 12Z SATURDAY. THUS DRY CONDITIONS WILL PREVAIL THROUGH
FRIDAY NIGHT. OVERNIGHT LOWS FRIDAY NIGHT WILL BE IN THE 50S.
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 335 AM CDT FRI JUL 25 2014
THE MAIN FEATURE OF THIS FORECAST PERIOD WILL BE THE UPPER LEVEL
LOW FORECAST BY MODELS TO MOVE SOUTHEAST FROM SASK THROUGH
MINNESOTA EVENTUALLY MERGING WITH A LONGWAVE TROUGH OVER THE
EASTERN US. AS THIS PROCESS TAKES PLACE THE LOW WILL USHER IN
COOLER SURFACE TEMPERATURES AND MORE STABLE AIR. SCATTERED SHOWERS
AND POSSIBLE AN ISOLATED THUNDERSTORM ARE FORECAST FOR THE NORTH
AND EAST ON SATURDAY. SUNDAY THROUGH TUESDAY WILL BE DRY AND
COOLER WITH HIGHS AS COOL AS THE UPPER 60S ACROSS THE TURTLE
MOUNTAINS SUNDAY...AND 70S SOUTH AND WEST. EVENTUALLY A HIGH
AMPLITUDE FLOW DEVELOPS ACROSS NORTH AMERICA WITH A LONGWAVE
TROUGH OVER THE EASTERN US AND A RIDGE OVER THE WEST BY THE MIDDLE
OF NEXT WEEK. THIS LEAVES THE NORTHERN PLAINS IN A SLIGHTLY
ANTICYCLONIC NORTHWEST FLOW REGIME THAT SHOULD SUPPRESS MUCH OF
THE CONVECTION WEDNESDAY AND THURSDAY WITH JUST ISOLATED
THUNDERSTORMS.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SATURDAY MORNING)
ISSUED AT 636 AM CDT FRI JUL 25 2014
A NARROW LINE OF LOW VFR/MVFR CIGS WILL HOVER FROM KMOT TO KBIS
THROUGH 13Z FRIDAY...AND OVER KJMS UNTIL 16Z FRIDAY. OTHERWISE SKC
WILL DOMINATE THE TERMINALS THROUGH THE TAF PERIOD. WESTERLY WINDS
GUSTING TO 25KT WILL SUBSIDE BY 02Z SATURDAY.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...WAA
SHORT TERM...KS
LONG TERM...WAA
AVIATION...WAA
AREA FORECAST DISCUSSION
NWS BISMARCK ND
334 AM CDT FRI JUL 25 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 335 AM CDT FRI JUL 25 2014
THE LATEST SURFACE ANALYSIS PLACES A COLD FRONT FROM NEAR SHERWOOD
TO JUST EAST OF MINOT AND SOUTH TO NEAR LINTON. WEAK PRESSURE
FALLS CONTINUE AHEAD OF THE FRONT WITH AN AREA OF SHOWERS AND
ISOLATED THUNDERSTORMS MOSTLY OVER NORTH CENTRAL NORTH DAKOTA.
THE FOG/STRATUS LOOP INDICATES POCKETS OF LOWER CLOUDS BEHIND THE
FRONT BUT STEADILY MOVING EAST. THE HRRR CEILING FORECAST HAS A
GOOD HANDLE ON THE CURRENT SITUATION AND ALSO PROGRESSIVELY MOVES
THE BACK EDGE OF THE LOWER CLOUDS THROUGH THE JAMES RIVER VALLEY
BY 14Z. WATER VAPOR IMAGERY LOOP SHOWS AN UPPER LOW SPINNING OVER
SOUTHEASTERN ALBERTA WITH A DRIER WESTERLY FLOW INTO NORTH DAKOTA.
ALBEIT A FEW DISTURBANCES ARE EMBEDDED WITHIN THE FLOW BUT THESE
ARE NOT EXPECTED TO HAVE MUCH OF AN IMPACT DURING THE SHORT TERM
PERIOD. THUS EXPECT A MOSTLY SUNNY SKY WITH BREEZY CONDITIONS AS
WESTERLY WINDS WILL RANGE BETWEEN 15 AND 25 MPH. HIGHS TODAY WILL
RANGE FROM THE UPPER 70S NORTH TO LOWER 80S SOUTH. AN AREA OF
SHOWERS WILL DEVELOP OVER SOUTH DAKOTA TONIGHT AND REMAIN SOUTH OF
NORTH DAKOTA/SOUTH DAKOTA BORDER. LATE FRIDAY NIGHT THERE WILL
ALSO BE AN AREA OF SHOWERS SLIDING INTO SOUTHERN SASKATCHEWAN AND
MANITOBA...BUT THESE SHOWERS WILL REMAIN NORTH OF THE BORDER
THROUGH 12Z SATURDAY. THUS DRY CONDITIONS WILL PREVAIL THROUGH
FRIDAY NIGHT. OVERNIGHT LOWS FRIDAY NIGHT WILL BE IN THE 50S.
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 335 AM CDT FRI JUL 25 2014
THE MAIN FEATURE OF THIS FORECAST PERIOD WILL BE THE UPPER LEVEL
LOW FORECAST BY MODELS TO MOVE SOUTHEAST FROM SASK THROUGH
MINNESOTA EVENTUALLY MERGING WITH A LONGWAVE TROUGH OVER THE
EASTERN US. AS THIS PROCESS TAKES PLACE THE LOW WILL USHER IN
COOLER SURFACE TEMPERATURES AND MORE STABLE AIR. SCATTERED SHOWERS
AND POSSIBLE AN ISOLATED THUNDERSTORM ARE FORECAST FOR THE NORTH
AND EAST ON SATURDAY. SUNDAY THROUGH TUESDAY WILL BE DRY AND
COOLER WITH HIGHS AS COOL AS THE UPPER 60S ACROSS THE TURTLE
MOUNTAINS SUNDAY...AND 70S SOUTH AND WEST. EVENTUALLY A HIGH
AMPLITUDE FLOW DEVELOPS ACROSS NORTH AMERICA WITH A LONGWAVE
TROUGH OVER THE EASTERN US AND A RIDGE OVER THE WEST BY THE MIDDLE
OF NEXT WEEK. THIS LEAVES THE NORTHERN PLAINS IN A SLIGHTLY
ANTICYCLONIC NORTHWEST FLOW REGIME THAT SHOULD SUPPRESS MUCH OF
THE CONVECTION WEDNESDAY AND THURSDAY WITH JUST ISOLATED
THUNDERSTORMS.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z FRIDAY NIGHT)
ISSUED AT 335 AM CDT FRI JUL 25 2014
SATELLITE IMAGERY ALONG WITH SURFACE OBSERVATIONS INDICATE POCKETS
OF MVFR CIGS AT KMOT/KBIS/KJMS. THIS AREA OF LOW CIGS WILL MAKE
A STEADY PROGRESS EAST AND OUT OF KJMS TERMINAL BY 14Z FRIDAY.
OTHERWISE EXPECT VFR CIGS/VSBYS NEXT 24HR WITH WESTERLY WINDS
BETWEEN 15 AND 25 MPH THROUGH FRIDAY EVENING.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...KS
LONG TERM...WAA
AVIATION...KS
AREA FORECAST DISCUSSION
NWS BISMARCK ND
1158 PM CDT THU JUL 24 2014
.UPDATE...
ISSUED AT 1158 PM CDT THU JUL 24 2014
LATEST LOCAL RADAR SHOWS ISOLATED SHOWERS AND THUNDERSTORMS ALONG
AND SOUTH OF I-94 WITH SCATTERED SHOWERS AND THUNDERSTORMS OCCURRING
NORTH. COLD FRONTAL SYSTEM ALONG A KENMARE TO GLEN ULLIN LINE IS
CONTINUING TO MOVE EAST. WILL MAINTAIN AN EASTWARD PROPAGATION OF
POPS/SKY GRIDS OVERNIGHT...DECREASING FROM WEST TO EAST. MINOR
ADJUSTMENTS TO CURRENT FORECAST.
UPDATE ISSUED AT 1018 PM CDT THU JUL 24 2014
SEVERE THUNDERSTORM WATCH 439 WAS ALLOWED TO EXPIRE AT 03 UTC AS
STORMS WILL BE PROPAGATING INTO A LESS FAVORABLE ENVIRONMENT ACROSS
CENTRAL NORTH DAKOTA. STRONG WINDS BEHIND THE LINE OF
THUNDERSTORMS ACROSS WESTERN NORTH DAKOTA HAVE STEADILY DECREASED
WITH SUNSET. WIND GUSTS ARE EXPECTED TO REMAIN BELOW 40 MPH...AND
THE HIGH WIND WARNING AND WIND ADVISORY THAT WERE IN EFFECT HAVE
BEEN CANCELLED.
UPDATE ISSUED AT 851 PM CDT THU JUL 24 2014
ISSUED A WIND ADVISORY FOR STRONG WINDS BEHIND THE OCCLUDING FRONT
ACROSS SOUTHWEST NORTH DAKOTA THROUGH 06 UTC.
UPDATE ISSUED AT 812 PM CDT THU JUL 24 2014
VERY STRONG WESTERLY WINDS WITH GUSTS IN EXCESS OF 50KTS HAVE BEEN
WIDESPREAD BEHIND THE LINE OF CONVECTION AND OCCLUDING FRONT
ACROSS NORTHEAST MONTANA. THIS IS EXPECTED TO CONTINUE INTO MUCH
OF WESTERN NORTH DAKOTA BEHIND THE LINE OF STORMS. THUS...A HIGH
WIND WARNING HAS BEEN ISSUED THROUGH 06 UTC FOR MUCH OF THE WEST.
UPDATE ISSUED AT 655 PM CDT THU JUL 24 2014
PER COORDINATION WITH SPC...SEVERE THUNDERSTORM WATCH 439 HAS BEEN
EXPANDED TO INCLUDE THE SOUTHWEST COUNTIES OF GOLDEN
VALLEY...BILLINGS...STARK...SLOPE...BOWMAN...HETTINGER AND ADAMS
COUNTIES UNTIL 03 UTC.
UPDATE ISSUED AT 540 PM CDT THU JUL 24 2014
THE 20 UTC AND INCOMING 21 UTC HRRR ITERATIONS HAVE A GOOD HANDLE
ON THE CURRENT CONVECTION ACROSS EASTERN MONTANA...AND WILL LEAN
HEAVILY ON THEIR SOLUTIONS FOR THE REMAINDER OF THE EVENING AND
OVERNIGHT. DID COORDINATE WITH SPC AT 2230 UTC REGARDING A
POTENTIAL EXPANSION OF SEVERE THUNDERSTORM WATCH 439 INTO
SOUTHWEST NORTH DAKOTA AS ROBUST CONVECTION ACROSS SOUTHEAST
MONTANA CONTINUES TO PROPAGATE NORTHEAST. WILL HOLD OFF FOR
NOW AS ALL REPORTS HAVE BEEN SUB-SEVERE. HOWEVER...SHOULD
CONVECTION STRENGTHEN AS IT APPROACHES BAKER...A WATCH EXPANSION
MAY BE NEEDED.
UPDATE ISSUED AT 410 PM CDT THU JUL 24 2014
SEVERE THUNDERSTORM WATCH 439 HAS BEEN ISSUED FOR NORTHWEST NORTH
DAKOTA THROUGH 03 UTC. PER COORDINATION WITH SPC...SEVERE
CONVECTION ACROSS NORTHWEST NORTH DAKOTA WILL LIKELY HOLD OFF
UNTIL AROUND 00-01 UTC AS STORMS ACROSS NORTH CENTRAL AND NORTHEAST
MONTANA COINCIDENT WITH THE BEST UPPER LEVEL FORCING PROPAGATE
EAST INTO NORTH DAKOTA...CLOSE TO THE 19 UTC HRRR SOLUTION.
&&
.SHORT TERM...(THIS EVENING THROUGH FRIDAY)
ISSUED AT 310 PM CDT THU JUL 24 2014
SURFACE LOW OVER CENTRAL ALBERTA WITH A TROUGH EXTENDING SOUTHWARD
INTO CENTRAL/EASTERN MONTANA TO THE WYOMING/SOUTH DAKOTA BORDER. AT
UPPER LEVELS...STRONG UPPER LOW OVER CENTRAL ALBERTA WITH SOUTHWEST
FLOW ALOFT AND EMBEDDED SHORTWAVE ENERGY IMPULSES FORECAST TO MOVE
THROUGH THE UPPER LEVEL FLOW. MOST OF THE UPPER LEVEL ENERGY APPEARS
TO BE FOCUSED MORE NORTH OF THE CANADIAN BORDER...BUT PLENTY OF CAPE
AND SHEAR IN PLACE SOUTHWARD ALONG AND AHEAD OF THE SURFACE TROUGH.
MID-LEVEL CAP WAS BUILDING AHEAD OF THE TROUGH...BUT ISOLATED
ELEVATED THUNDERSTORMS HAD DEVELOPED OVER WESTERN NORTH DAKOTA AND
WERE MOVING EAST AT 30-35 MPH...LIKELY ASSOCIATED WITH WEAK UPPER
LEVEL IMPULSES IN THE UPPER FLOW - BUT NOT SURFACE-BASED.
THE MAIN ACTION IS EXPECTED LATER THIS AFTERNOON/EARLY EVENING AS
THE SURFACE TROUGH MOVES INTO WESTERN NORTH DAKOTA...AND INTO
CENTRAL NORTH DAKOTA THROUGH THE EVENING. THIS WILL BE SUPPORTED BY
MORE VIGOROUS UPPER LEVEL IMPULSES. SEVERE STORMS POSSIBLE...BUT
BEST CAPE IS ALONG AND AHEAD OF THE TROUGH...AND THE BEST SHEAR IS
RIGHT ALONG AND BEHIND THE TROUGH.
EXPECTING BEST CHANCES OF THUNDERSTORMS IN THE WEST LATE AFTERNOON
AND EARLY EVENING...AND BEST CHANCES IN THE CENTRAL FROM MID/LATE
EVENING INTO THE EARLY MORNING HOURS.
FRIDAY LOOKS DRY AND BREEZY WEST WINDS WITH HIGHS MAINLY IN THE
UPPER 70S TO MID 80S.
.LONG TERM...(FRIDAY NIGHT THROUGH THURSDAY)
ISSUED AT 310 PM CDT THU JUL 24 2014
UPPER LEVEL LOW PROPAGATING EAST ACROSS SOUTH CENTRAL
CANADA...INTO FAR SOUTHEASTERN SASKATCHEWAN BY 12Z SAT...WILL
DRAG A SURFACE COLD FRONT THROUGH THE NORTHERN PLAINS SATURDAY
MORNING...THEN A SECONDARY COLD FRONT SATURDAY AFTERNOON/EVENING
AS THE LOW CONTINUES TOWARDS NORTHWESTERN MN. UPPER LEVEL FORCING
WITH THE LOW COUPLED WITH SFC CONVERGENCE ALONG THE FRONT WILL
BOTH COMBINE WITH LINGERING BOUNDARY LAYER MOISTURE TO RESULT IN
SCATTERED SHOWERS/THUNDERSTORMS ACROSS THE NORTH SAT
MORNING...WITH COVERAGE OF PRECIPITATION SPREADING SOUTHEAST
DURING THE DAY.
SLIGHT CHANCES FOR PRECIPITATION OVER MY FAR EASTERN COUNTIES SAT
NIGHT/SUNDAY WITH THE UPPER LEVEL JET ACROSS THE MIDWEST.
STRONG SURFACE HIGH PRESSURE BUILDS INTO THE REGION SUNDAY/SUNDAY
NIGHT AHEAD OF AN UPPER LEVEL RIDGE OVER THE WESTERN CONUS...THEN
REMAINS QUASI-STATIONARY THROUGH THE DAY TUESDAY GIVING THE
NORTHERN PLAINS REGION A DRY WEATHER SPELL. BOTH THE 12Z GFS/ECMWF
INDICATE RIDGE RIDER S/WVS MOVING THROUGH THE DAKOTAS TUESDAY
NIGHT THROUGH THURSDAY. WITH THE SFC HIGH MOVING SOUTHEAST...WILL
SEE SPOTTY SHOWER/THUNDERSTORM CHANCES BEGINNING MID-WEEK.
TEMPERATURES WILL BE ON THE COOL SIDE FOR THE END OF JULY SAT-
MON...IN THE 70S...THEN WARM INTO THE 80S TUE-THURS WITH THE
BUILDING RIDGE.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z FRIDAY NIGHT)
ISSUED AT 1158 PM CDT THU JUL 24 2014
A COLD FRONT WILL MAINTAIN AN EASTWARD MOVEMENT ACROSS
KMOT/KBIS/KJMS THROUGH 12Z FRIDAY. ISOLATED TO SCATTERED SHOWERS
AND THUNDERSTORMS WILL CONTINUE OVERNIGHT BUT DECREASE FROM WEST
TO EAST. EXPECT A WIND SHIFT TO THE NORTHWEST BETWEEN 15 AND 25
MPH WHICH WILL CONTINUE INTO FRIDAY.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...KS
SHORT TERM...JV
LONG TERM...NH
AVIATION...KS
AREA FORECAST DISCUSSION
NWS NORMAN OK
954 PM CDT SAT JUL 26 2014
.UPDATE...
NO CHANGES TO THE PACKAGE THIS EVENING. HRRR AND LOCAL WRK STILL
HAVE A SLIGHT SIGNAL FOR PRECIPITATION TO THE NORTH WITH THE FRONT
SLIDING INTO THE AREA OVERNIGHT SO WILL LEAVE THE SLIGHT CHANCES
IN... ALTHOUGH NOT REAL BULLISH ON THOSE CHANCES.
&&
.PREV DISCUSSION... /ISSUED 644 PM CDT SAT JUL 26 2014/
AVIATION...
27/00Z TAFS...VFR CONDITIONS EXPECTED TO PREVAIL THROUGH FORECAST
PERIOD. FRONTAL BOUNDARY WILL MAKE SLOW PROGRESS OVER TERMINALS
TONIGHT AND TOMORROW. SHOULD ENTER NORTHWEST OKLAHOMA BEFORE
DAYBREAK AND MAKE IT TO KSPS LAST FEW HOURS OF THIS FORECAST
PERIOD. ALTHOUGH A FEW STORMS WILL LIKELY BE SEEN NEAR FRONT...
DISPARITY AMONG SHORT-TERM MODELS...ANTICIPATED CAP...AND WEAK
CONVERGENCE ALONG FRONT WILL PRECLUDE MENTIONING TSRA IN
TERMINALS. BETTER CHANCES FOR STORMS WILL BE NEAR END OF FORECAST
AND BEYOND ACROSS SOUTHERN HALF OF OKLAHOMA INTO NORTHERN TEXAS.
PREV DISCUSSION... /ISSUED 207 PM CDT SAT JUL 26 2014/
DISCUSSION...
A FRONT WILL MOVE INTO NORTHERN OKLAHOMA EARLY SUNDAY AND BRING A
LITTLE COOLER WEATHER WITH IT. HOWEVER, TEMPERATURES SOUTH OF THE
FRONT ARE EXPECTED TO BE ABOUT AS HOT AS TODAY AND IN SOME ZONE OF
CENTRAL OR SOUTHERN OKLAHOMA AHEAD OF THE FRONT MAY EXCEED TODAY`S
AFTERNOON TEMPERATURES. THE HEAT ADVISORY HAS BEEN EXTENDED
THROUGH THE DAYTIME ON SUNDAY FOR PART OF SOUTHERN OKLAHOMA AND
NORTHERN TEXAS. ISOLATED THUNDERSTORMS ARE EXPECTED ALONG THE
FRONT AS IT MOVES SOUTH THROUGH THE DAY. THE STALLING OF THIS
FRONT SOUTH OF THE RED RIVER MONDAY NIGHT WILL PROVIDE A FOCUS FOR
A MUCH BETTER CHANCE FOR RAIN AND THUNDERSTORMS EARLY TUESDAY.
THESE WILL LIKELY BE CONCENTRATED IN WESTERN AND SOUTHWESTERN
OKLAHOMA IN THE UPSLOPE BOUNDARY FLOW INTO THE FRONT. WEAK MID-
LEVEL FLOW FROM THE NORTHWEST WILL HELP BRING A STRONGER FRONT
INTO OKLAHOMA WEDNESDAY. THIS IS EXPECTED TO BE ACCOMPANIED BY AN
UPPER-LEVEL TROUGH AND PLENTIFUL MOISTURE FOR MORE WIDESPREAD RAIN
AND A COOLER AIRMASS. LESSER RAIN CHANCES WILL CONTINUE THURSDAY
WHEN THE FRONT IS LIKELY STILL PRESENT. AFTER A MILD AND CLOUDY
MID-WEEK, A SLOW WARMING TREND BEGINS INTO NEXT WEEKEND.
&&
.PRELIMINARY POINT TEMPS/POPS...
OKLAHOMA CITY OK 74 98 70 90 / 10 20 30 30
HOBART OK 74 101 70 92 / 10 20 30 30
WICHITA FALLS TX 77 104 75 95 / 0 10 20 30
GAGE OK 70 92 65 88 / 20 20 30 30
PONCA CITY OK 76 93 67 88 / 20 20 20 0
DURANT OK 76 98 74 94 / 0 10 30 40
&&
.OUN WATCHES/WARNINGS/ADVISORIES...
OK...HEAT ADVISORY UNTIL 8 PM CDT SUNDAY FOR OKZ032-037>048-050>052.
TX...HEAT ADVISORY UNTIL 8 PM CDT SUNDAY FOR TXZ085-086-088>090.
&&
$$
AREA FORECAST DISCUSSION
NWS GREENVILLE-SPARTANBURG SC
1148 AM EDT FRI JUL 25 2014
.SYNOPSIS...
HIGH PRESSURE WILL BUILD IN BEHIND A DEPARTING COLD FRONT ON FRIDAY
LASTING THROUGH THE MAJORITY OF THE WEEKEND. ANOTHER COLD FRONT IS
EXPECTED TO REACH THE AREA FROM THE NORTHWEST ON MONDAY MORNING AND
INTO MONDAY AFTERNOON POTENTIALLY LEADING TO SCATTERED
THUNDERSTORMS. HIGH PRESSURE WILL ONCE AGAIN REGAIN CONTROL ON
TUESDAY LASTING THROUGH THE REMAINDER OF THE WORK WEEK WITH ONLY
MINIMAL PRECIPITATION THREATS BY WEEKS END.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 11 AM...ALTHOUGH THE WEAK FRONT HAS SAGGED INTO THE SC
MIDLANDS AND CENTRAL GA THIS MORNING...A MOIST E/NE FLOW NORTH OF
THE BOUNDARY IS RESULTING IN AREAS OF LOW STRATUS AND STRATOCU
ACROSS THE AREA. THIS SHOULD CONTINUE TO LIFT/EVOLVE INTO A FAIRLY
EXTENSIVE AFTERNOON CUMULUS FIELD. THE PRIMARY CONCERN FOR THIS
PERIOD WILL BE WHETHER A FEW OF THESE CUMULUS CLOUDS CAN DEVELOP
INTO THUNDERSTORMS THIS AFTERNOON. THE DIFFERENCE BETWEEN FORECAST
RAP AND NAM SOUNDINGS IS QUITE STRIKING...AS THE RAP MAINTAINS A
RATHER FORMIDABLE CAP ACROSS THE AREA THROUGH THE AFTERNOON...WHILE
THE NAM TRIES TO ELIMINATE IT. ALTHOUGH DEWPOINTS WILL BE A LITTLE
LOWER THAN TYPICAL OF THIS TIME OF YEAR...THEY SHOULD STILL BE HIGH
ENOUGH TO YIELD MODEST AMOUNTS OF CAPE THIS AFTERNOON. THUS...IF THE
CAP DOES INDEED ERODE...IT SEEMS REASONABLE THAT A FEW SHOWERS/TSRA
WILL DEVELOP ACROSS THE HIGH TERRAIN...AS IS INDICATED IN THE
CURRENT FORECAST. THE ONLY REAL CHANGE OF NOTE WILL BE TO INCLUDE A
SLIGHT CHANCE POP NEARER THE FRONT ACROSS THE FAR SOUTHERN PIEDMONT
AREAS. OTHERWISE...MAX TEMPS SHOULD BE ABOUT A CATEGORY BELOW CLIMO
OWING TO THE COOL E/NE FLOW AND CONSIDERABLE CUMULUS COVER.
AS OF 640 AM...LOW CLOUDS SPREADING IN FROM THE EAST OR ALREADY IN
PLACE ACROSS THE MTNS SHUD LIFT OR SCATTER OUT BY NOON. OTHERWISE...
GOING FCST STILL LOOKS ON TRACK. UPDATES MAINLY FOR CURRENT
CONDITIONS.
AS OF 305 AM...SLOW MOVING COLD FRONT KEEPING ENUF LOW LEVEL
CONVERGENCE ACROSS THE SRN UPSTATE TO BREAK THE CAP AND PRODUCE
ISOLATED SHRA. THESE SHUD END OR MOVE SOUTH OF THE AREA BY DAYBREAK
AS THE FRONT MOVES OUT OF THE AREA.
ALTHOUGH THE FRONT MOVES SOUTH OF THE AREA...GUIDANCE IS NEARLY
UNANIMOUS KEEPING LOW LEVEL MOISTURE ACROSS THE AREA. IN ADDITION...
LOW LEVEL FLOW BECOMES SELY LEADING TO WEAK UPSLOPE FLOW. THIS IS
FORECAST TO PROVIDE ENUF LIFT TO TAP THE ELEVATED INSTABILITY AND
PRODUCE ISOLATED TO SCT CONVECTION ALONG THE BLUE RIDGE AND WEST
ACROSS THE MTNS. GIVEN THE MDL SUPPORT...HAVE CHANGED THE FORECAST
TO INCLUDE POP IN THIS AREA. THERE MAY ALSO BE SOME CONVECTION
ACROSS THE FAR SRN CWFA AS THAT AREA WILL BE CLOSE TO THE FRONT.
HOWEVER...BEST CHC WILL BE SOUTH OF THE CWFA. CLOUDS WILL LINGER
THRU THE MORNING ACROSS MUCH OF THE NRN AND ERN CWFA...BEFORE MIXING
OUT BY AFTERNOON. THIS AND THE COOLER AIR MASS BEHIND THE FRONT WILL
LEAD TO HIGHS A LITTLE BELOW NORMAL.
CONVECTION SHUD DISSIPATE DURING THE EVENING WITH LOSS OF HEATING.
HOWEVER...CANNOT RULE OUT SOME LINGERING SHRA OVER THE BLUE RIDGE
LATE INTO THE EVENING OR EARLY OVERNIGHT BEFORE THE LOW LEVEL FLOW
BECOMES SWLY. LOWS SHUD BE NEAR NORMAL.
&&
.SHORT TERM /SATURDAY THROUGH SUNDAY NIGHT/...
AS OF 230 AM EDT FRIDAY...THE SHORT TERM PERIOD INITIALIZES SATURDAY
MORNING WITH REMNANT FRONT WELL TO THE SOUTHEAST ALONG THE
CAROLINA/GEORGIA COASTLINE. SURFACE HIGH PRESSURE WILL QUICKLY
BUILD UNDER RISING HEIGHTS ALOFT. DESPITE WEAK LEE TROF DEVELOPING
JUST EAST OF THE FORECAST AREA POTENTIALLY PROVIDING A FOCUS FOR
AFTERNOON CONVECTION...SOUNDINGS INDICATE A SUBSTANTIAL LOW/MID
LEVEL CAP IN PLACE. NOT EXPECTING ANY POTENTIAL UPDRAFTS TO BREAK
THROUGH THE DEEP INHIBITION THEREFORE KEPT THE FORECAST DRY FOR
SATURDAY.
ALSO KEPT FORECAST DRY THROUGH SUNDAY MORNING AS UPPER HEIGHTS ARE
SLOW TO FALL DUE TO APPROACHING UPPER TROF AND ASSOCIATED SURFACE
COLD FRONT. STILL THINK AREA OF GREATEST LIFT AND LOWEST INHIBITION
WILL REMAIN TIED TO LEE TROF REDEVELOPMENT EAST OF THE I77 CORRIDOR
THEREFORE CONTINUE WITH DRY FORECAST FOR THE PIEDMONT REGION THROUGH
THE AFTERNOON. FURTHER WEST...HEIGHTS WILL BEGIN TO FALL RAPIDLY AS
UPPER SHORT WAVE AND ASSOCIATED MOISTURE ADVECT INTO THE
CENTRAL/SOUTHERN APPS. MODELS TEND TO AGREE ON AT LEAST SOME
PRECIPITATION PUSHING INTO THE NORTHERN MOUNTAINS BY MID/LATE
AFTERNOON ON SUNDAY...WITH CHANCES INCREASING AHEAD OF THE
APPROACHING FRONT THROUGH THE OVERNIGHT. THEREFORE...SOLID CHANCE
POPS ARE FEATURED SUNDAY EVENING ALONG THE HIGHER TERRAIN OF NC
INCREASING TO NEAR LIKELY POPS BY MONDAY MORNING NEAR THE TN
BORDER. ELSEWHERE POPS TAPER DOWN SHARPLY TO SLIGHT CHANCE LEVELS
OVER THE NC/SC FOOTHILLS AND WESTERN MOST AREAS OF THE PIEDMONT.
TEMPERATURES THROUGH THE SHORT TERM PERIOD WILL GRADUALLY WARM AS
SOUTHERLY FLOW RAMPS UP AHEAD OF APPROACHING SURFACE TROF.
EXPECTING HIGHS ON BOTH SATURDAY AND SUNDAY TO SURGE TO ABOVE NORMAL
LEVELS WITH MID 90S POSSIBLE FOR SOUTHERN PORTIONS OF THE FORECAST
AREA ON SUNDAY.
&&
.LONG TERM /MONDAY THROUGH THURSDAY/...
AS OF 315 AM EDT FRIDAY...THE EXTENDED RANGE PERIOD WILL BEGIN WITH
A RATHER ACTIVE PATTERN ON MONDAY MORNING. STRONG HEIGHT FALLS WILL
BE ADVECTING IN FROM THE WEST AS A COLD FRONT STRETCHES ALONG THE
APPALACHIAN CHAIN FROM A PARENT SURFACE CYCLONE ACROSS THE EASTERN
GREAT LAKES. POPS WILL INITIALIZE AT HIGH END CHANCE LEVELS ACROSS
THE HIGHER TERRAIN AS THE PRE-FRONTAL ACTIVITY PUSHES INTO THE REGION
AROUND OR JUST BEFORE DAYBREAK MONDAY. THE ENTIRE COMPLEX WILL
CONTINUE ADVECTING EAST THROUGH THE MORNING AND EARLY AFTERNOON
HOURS ALLOWING FOR SOME DIURNAL DESTABILIZATION AHEAD ACROSS THE
NC/SC PIEDMONT REGIONS. THERE IS STILL SOME UNCERTAINTY REGARDING
OVERALL MAGNITUDE OF INSTABILITY THAT WILL BUILD AHEAD OF THE FRONT
AS ABUNDANT SKY COVER WILL WORK TO LIMIT HEATING. THAT
SAID...MODEST WARM SECTOR ALREADY IN PLACE WILL NOT NEED MUCH
HEATING FOR LAPSE RATES TO SUPPORT SUBSTANTIAL LOW LEVEL LIFT.
ALOFT DRIER AIR WILL BE ADVECTING IN AS STRONG WNW FLOW ASSOCIATED
WITH TROF AXIS PUSHES INTO THE REGION. THIS WILL ALLOW MID LEVEL
LAPSE RATES TO STEEPEN...POTENTIALLY LEADING TO A FAIRLY UNSTABLE
PROFILE. SPEAKING OF...LATEST GFS FORECAST SOUNDINGS INDICATE
NEARLY 1500J/KG SBCAPE AND LONG STRAIGHT HODOGRAPHS PRODUCING DEEP
LAYER SHEAR IN EXCESS OF 35KTS SUGGESTING MULTICELL STRONG/SEVERE
THUNDERSTORMS. ALL THAT SAID...THERE IS STILL PLENTY OF TIME FOR THE
PATTERN TO CHANGE SLIGHTLY WHICH COULD SUBSTANTIALLY ALTER THE
OUTCOME. THUS...DUE TO RANGE IN THE FORECAST...KEPT POPS CAPPED AT
CHANCE LEVELS FOR THE ENTIRE REGION ON MONDAY AFTERNOON.
SURFACE HIGH PRESSURE WILL BUILD INTO THE REGION BEHIND THE FRONT
FOR TUESDAY AND WEDNESDAY LEADING TO LOWER PRECIPITATION CHANCES
DESPITE PERSISTENT UPPER TROF REMAINING NEARLY STATIONARY. FORECAST
WILL FEATURE SLIGHT CHANCE POPS ACROSS THE HIGH TERRAIN THROUGH
WEDNESDAY MORNING AMIDST STRONG NW FLOW. THE SURFACE RIDGE REMAINS
DOMINATE THROUGH THE REMAINDER OF THE PERIOD AS IT REPOSITIONS
ITSELF TO THE NORTHEAST AND EXTENDS IN A WEDGE LIKE PATTERN ALONG
THE LEE SIDE OF THE APPALACHIANS BY THURSDAY. SURFACE FLOW WILL
SHIFT TO MORE OF AN EAST TO SOUTHEAST COMPONENT LEADING TO POTENTIAL
UPSLOPE/UPGLIDE PRECIPITATION INTO FRIDAY. THUS CHANCE LEVEL POPS
ARE ONCE AGAIN FEATURED THROUGH THE REMAINDER OF THE FORECAST ALONG
THE HIGH TERRAIN WITH SLIGHT CHANCE POPS HIGHLIGHTED ELSEWHERE.
TEMPERATURES WILL GRADUALLY COOL BEHIND THE FROPA ON MONDAY WITH
HIGHS TOPPING OUT NEARLY A CATEGORY BELOW NORMAL BY THURSDAY FOR
SOME LOCATIONS.
&&
.AVIATION /16Z FRIDAY THROUGH TUESDAY/...
AT KCLT...IFR STRATUS HAS SPREAD ACROSS THE AIRFIELD AND WILL
CONTINUE THRU MID-MORNING WHEN A SLOW RISE TO LOW VFR BY 18Z
DEVELOPS. THAT SAID...MOISTURE IS SHALLOW AND CIGS COULD SCATTER OUT
BEFORE LIFTING. FEW TO SCT LOW VFR CLOUDS EXPECTED THRU THE EVENING
AND OVERNIGHT. NELY WIND BECOMES ENE THIS AFTERNOON AND EVENING THEN
CALM OVERNIGHT. RIGHT NOW...DO NOT EXPECT ANY RESTRICTIONS
OVERNIGHT.
ELSEWHERE...LOW STRATUS IS MAKING A RUN FROM THE EAST AT THE NON MTN
SITES. LOW VFR CIGS HAVE DEVELOPED AND MVFR OR EVEN THE IFR DECK
COULD DEVELOP. IF SO...SHUD BE A RELATIVELY QUICK RETURN TO VFR...
GENERALLY BEFORE NOON. THEN VFR EXPECTED THRU THE REST OF THE
PERIOD. NELY WIND BECOMES ELY OR SELY BY LATE AFTERNOON WITH
GENERALLY CALM WIND OVERNIGHT. KAVL WILL SEE MVFR OR IFR THIS
MORNING WITH LOW VFR DEVELOPING BY NOON. NLY WIND BECOMES SLY FOR
THE AFTERNOON...THEN CALM OVERNIGHT. ISOLATED CONVECTION WILL
DEVELOP ACROSS THE MTNS...BUT CHC TOO LOW FOR TAF INCLUSION. KAVL
COULD SEE RESTRICTIONS FROM FOG TOWARD DAYBREAK SAT.
OUTLOOK...SAT THROUGH SUNDAY MORNING SHOULD BE QUIET AND VFR...
EXCEPT FOR THE MTN VALLEYS WHERE EARLY MORNING FOG MAY OCCUR. SCT
THUNDERSTORMS MAY RETURN TO THE FORECAST AREA FOR SUNDAY
AFTERNOON...THOUGH MORE LIKELY MON...AS ANOTHER COLD FRONT
APPROACHES AND THEN MOVES THROUGH THE AREA BY MON NIGHT.
CONFIDENCE TABLE...
15-21Z 21-03Z 03-09Z 09-15Z
KCLT HIGH 88% HIGH 100% HIGH 100% HIGH 100%
KGSP HIGH 97% HIGH 100% HIGH 100% HIGH 100%
KAVL HIGH 88% HIGH 100% HIGH 89% HIGH 90%
KHKY HIGH 89% HIGH 100% HIGH 100% HIGH 87%
KGMU HIGH 98% HIGH 97% HIGH 100% HIGH 100%
KAND HIGH 88% HIGH 100% HIGH 100% HIGH 93%
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...CDG
NEAR TERM...JDL/RWH
SHORT TERM...CDG
LONG TERM...CDG
AVIATION...RWH
AREA FORECAST DISCUSSION...UPDATED
NWS BROWNSVILLE TX
1235 PM CDT FRI JUL 25 2014
.DISCUSSION...UPDATED FOR LATEST AVIATION DISCUSSION BELOW.
&&
.AVIATION...
A WEAK SHEAR AXIS IN THE UPPER ATMOSPHERE...COMBINED WITH AMPLE
BOUNDARY LAYER MOISTURE...MAY AID IN THE DEVELOPMENT OF ISOLD
-SHRA/TSRA ACROSS THE REGION THIS AFTERNOON. IT LOOKS LIKE
CONVECTION COULD DEVELOP BETWEEN 25/1700-1900 IN VICINITY OF US-77
CORRIDOR...WITH ADDITIONAL DEVELOPMENT POSSIBLE FARTHER W BY 25/2100
UTC AS THE SEABREEZE MOVES W. CIGS MAY BE LOCALLY REDUCED INTO MVFR
TERRITORY FOR AN HOUR OR SO IN VICINITY OF ANY -SHRA/TSRA. NO
-SHRA/TSRA ARE ANTICIPATED SATURDAY AS THE BOUNDARY LAYER STARTS TO
DRY.
OVERALL...THE ODDS OF SEEING -SHRA/TSRA AT THE MAJOR VALLEY
TERMINALS ARE VERY LOW THIS AFTERNOON. I PLAN ON CONTINUING A DRY
FORECAST FOR KBRO...KHRL...AND KMFE FOR THE 1800 UTC TAF PACKAGE...
WITH ONLY SCTD CU ANTICIPATED THROUGH SUNSET.
GUSTY SE WINDS AROUND 15 KTS SHOULD DIMINISH AFTER SUNSET...THEN
INCREASE AGAIN BY MID-MORNING SATURDAY. /53/
&&
.PREV DISCUSSION... /ISSUED 1123 AM CDT FRI JUL 25 2014/
DISCUSSION...
QUIET WEATHER CONDITIONS ACROSS THE FORECAST AREA LATE THIS
MORNING...WITH HARDLY A CLOUD IN THE SKY. WATER VAPOR
IMAGERY...AND SUBJECTIVE ANALYSES CONTINUE TO INDICATE AN UPPER-
LEVEL SHEAR AXIS EXTENDING FROM THE NORTHERN GULF COAST INTO OUR
AREA. ALL INDICATIONS SUGGEST THAT BOUNDARY LAYER MOISTURE SHOULD
REMAIN SUFFICIENT TO ALLOW SOME ISOLATED CONVECTION TO DEVELOP
THIS AFTERNOON.
CONVECTION COULD DEVELOP NEAR THE IH-69E/US-77 CORRIDOR BETWEEN
NOON AND 2 PM AS THE SEABREEZE STARTS TO MOVE INLAND. HOWEVER...WITH
THE DEEPEST MOISTURE EXPECTED TO REMAIN AROUND THE IH-69C/US-281
CORRIDOR...THE GREATEST COVERAGE IS EXPECTED TO BE IN THIS REGION
THIS AFTERNOON AS SEABREEZE MOVES WESTWARD. THIS TREND IS
GENERALLY SUPPORTED BY RECENT HRRR MODEL RUNS. ALL THAT
SAID...PRECIPITATION PROBABILITIES AND TIMING HAVE BEEN ADJUSTED SLIGHTLY.
OTHERWISE...THE ONGOING FORECAST APPEARS TO BE IN DECENT SHAPE
WITH ONLY MINOR ADJUSTMENTS MADE HERE AND THERE TO ACCOUNT FOR
TRENDS IN THE OBSERVATIONAL DATA. ANY CHANGES TO FORECAST HIGH OR
LOW TEMPERATURES ARE PROVIDED BELOW FOR YOUR PERUSAL.
ISC GRIDS HAVE BEEN SENT AND SHOULD BE POSTED TO THE INTERNET.
UPDATED TEXT FORECAST PRODUCTS WILL BE ISSUED SHORTLY. /53/
PREV DISCUSSION... /ISSUED 629 AM CDT FRI JUL 25 2014/
DISCUSSION...UPDATED FOR LATEST AVIATION DISCUSSION BELOW.
AVIATION...VFR CONDITIONS PREVAIL TODAY INTO TONIGHT WITH HIGH
PRESSURE CENTERED OVER NORTHWEST TEXAS. MID TO UPPER LEVEL
NORTHEAST FLOW WITH DRIER AIR TO LIMIT CLOUD COVER TO FEW-SCT. A
WEAKENING UPPER LOW PRESSURE TROUGH REMAINS CLOSE ENOUGH FOR
ISOLATED SHOWERS OR EVEN A THUNDERSTORM TO DEVELOP LATER THIS
AFTERNOON. LITTLE TO NO IMPACT ANTICIPATED AT THE 3 TERMINALS
SITE. LIGHT SOUTHEAST FLOW BECOMING MODERATE AS THE SEA BREEZE
MOVES EAST TO WEST BETWEEN 19-23Z
PREV DISCUSSION... /ISSUED 406 AM CDT FRI JUL 25 2014/
SHORT TERM /TODAY THROUGH SATURDAY/...WEAKENING 250MB SHEAR LINE
LIES ALONG THE TEXAS COAST WITH THE BASE OF THE TROUGH NOTED OVER
OUR WESTERN ZONES THIS MORNING. CENTER OF HOT RIDGE OVER THE TEXAS
PANHANDLE WITH DRIER NORTHEAST FLOW. WE SHOULD SEE A DECREASING
AREAL COVERAGE OF POPS AS THE DRIER AIR INFILTRATES THE REGION AND
THE AND THE TROUGH CONTINUES TO DAMPEN OUT. SPOTTY 20 PERCENT POPS
LOOK FAIR WITH A MORE TYPICAL SEA BREEZE DISTRIBUTION ANTICIPATED.
GRADIENT SLIGHTLY STRONGER TODAY WITH A STRONGER THERMAL LOW.
WINDS PICK UP MOSTLY LATER IN THE AFTERNOON AS THE SEA BREEZE
MOVES INLAND. TEMPERATURES REMAIN ABOVE NORMAL BUT JUST SLIGHTLY
DOWN A DEGREE OR TWO IN THE EAST AS THE SEA BREEZE COMES THROUGH A
BIT EARLIER.
TONIGHT...WARM AND MUGGY AND POSSIBLE A DEGREE WARM IF WINDS STAY UP
PASS MIDNIGHT.
SATURDAY...THE SHEAR LINE IS PRETTY MUCH LOST IN THE STRONGER
NORTHEAST FLOW AROUND THE RIDGE. MEAN RH LOWERS AND 850MB
TEMPERATURES RISE KEEPING RAIN CHANCES BELOW 10 PERCENT. EXPECT
AMBIENT TEMPERATURES TO PEAK ANOTHER DEGREE OR SO WITH LESS CLOUDS
AND LOWER RH. AFTERNOON BREEZES TO MAKE THE HEAT A BIT MORE
TOLERABLE.
LONG TERM /SATURDAY NIGHT THROUGH THURSDAY/...H5 RIDGE CONTINUES
TO DOMINATE THE LOCAL WEATHER INTO THE MIDDLE OF NEXT
WEEK...KEEPING TEMPERATURES ABOVE NORMAL. THICKNESS VALUES REMAIN
STABLE AND ATMOSPHERIC MOISTURE REMAIN WELL BELOW NORMAL THROUGH
MIDWEEK...WHICH WILL KEEP A CONSISTENT TEMPERATURE REGIME. HIGHS
WILL BE IN THE MID TO UPPER 90S ALONG THE COAST AND 100 TO 105 FOR
THE WESTERN AREAS. HEAT INDEX VALUES WILL REACH 105 TO 110
AREAWIDE EACH AFTERNOON. PW VALUES REMAIN AT OR BELOW 1.5 INCHES
INTO NEXT WEEK...WITH NO RAIN CHANCES AND EVEN MINIMAL CLOUD
COVER. FAR EXTENDED MODELS ARE BEGINNING TO INDICATE THE THE RIDGE
WILL FINALLY DISPLACE SOUTHWARD AS THE EASTERN TROUGH MAKES AN
UNUSUALLY FAR SOUTHWARD DRIVE. AN ACCOMPANYING COLD FRONT MAY
DRIVE INTO TEXAS AGAIN...WITH A POSSIBLE RETURN OF RAIN CHANCES
FOR THE FIRST WEEKEND IN AUGUST.
MARINE...
TODAY THROUGH SATURDAY...PRESSURE GRADIENT TO SLOWLY STRENGTHEN
LATER TODAY INTO SATURDAY. INTERACTION BETWEEN THE SURFACE RIDGE
OVER THE GULF AND THERMAL LOW PRESSURE INLAND TO PROVIDE THE
SLIGHTLY STRONGER WINDS INTO SATURDAY. WINDS STILL REMAIN LOW
ENOUGH WITH NO MENTION OF EXERCISE CAUTION OR ANY ADVISORIES.
STILL A FEW SHOWERS OVER THE OFFSHORE COASTAL WATERS THIS MORNING
BECOMING EVEN MORE ISOLATED THIS AFTERNOON AND TONIGHT.
SATURDAY NIGHT THROUGH MONDAY...MODEST SOUTHEAST WINDS CONTINUE
FOR THE LATTER HALF OF THE WEEKEND INTO EARLY NEXT WEEK AS THE
GULF RIDGE REMAINS FIRM AND THE HEAT LOW FLUCTUATES ACROSS WEST
TEXAS. ADVISORIES ARE NOT EXPECTED...BUT CAUTION MAY BE ADVISED
FOR THE LAGUNA SUNDAY AND MONDAY. LONG FETCH ACROSS THE GULF
BEGINS TO BUILD SEAS TO 3 TO 4 FEET EARLY NEXT WEEK.
&&
.BRO WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
GM...NONE.
&&
$$
THIS PRODUCT IS ALSO AVAILABLE ON THE WEB AT:
HTTP://WEATHER.GOV/RGV
SHORT TERM FORECASTER... BUTTS
LONG TERM FORECASTER... TOMASELLI
PSU/GRAPHICAST... MARTINEZ
AREA FORECAST DISCUSSION...UPDATED
NWS BROWNSVILLE TX
1123 AM CDT FRI JUL 25 2014
.DISCUSSION...
QUIET WEATHER CONDITIONS ACROSS THE FORECAST AREA LATE THIS
MORNING...WITH HARDLY A CLOUD IN THE SKY. WATER VAPOR
IMAGERY...AND SUBJECTIVE ANALYSES CONTINUE TO INDICATE AN UPPER-
LEVEL SHEAR AXIS EXTENDING FROM THE NORTHERN GULF COAST INTO OUR
AREA. ALL INDICATIONS SUGGEST THAT BOUNDARY LAYER MOISTURE SHOULD
REMAIN SUFFICIENT TO ALLOW SOME ISOLATED CONVECTION TO DEVELOP
THIS AFTERNOON.
CONVECTION COULD DEVELOP NEAR THE IH-69E/US-77 CORRIDOR BETWEEN
NOON AND 2 PM AS THE SEABREEZE STARTS TO MOVE INLAND. HOWEVER...WITH
THE DEEPEST MOISTURE EXPECTED TO REMAIN AROUND THE IH-69C/US-281
CORRIDOR...THE GREATEST COVERAGE IS EXPECTED TO BE IN THIS REGION
THIS AFTERNOON AS SEABREEZE MOVES WESTWARD. THIS TREND IS
GENERALLY SUPPORTED BY RECENT HRRR MODEL RUNS. ALL THAT
SAID...PRECIPITATION PROBABILITIES AND TIMING HAVE BEEN ADJUSTED SLIGHTLY.
OTHERWISE...THE ONGOING FORECAST APPEARS TO BE IN DECENT SHAPE
WITH ONLY MINOR ADJUSTMENTS MADE HERE AND THERE TO ACCOUNT FOR
TRENDS IN THE OBSERVATIONAL DATA. ANY CHANGES TO FORECAST HIGH OR
LOW TEMPERATURES ARE PROVIDED BELOW FOR YOUR PERUSAL.
ISC GRIDS HAVE BEEN SENT AND SHOULD BE POSTED TO THE INTERNET.
UPDATED TEXT FORECAST PRODUCTS WILL BE ISSUED SHORTLY. /53/
&&
.PREV DISCUSSION... /ISSUED 629 AM CDT FRI JUL 25 2014/
DISCUSSION...UPDATED FOR LATEST AVIATION DISCUSSION BELOW.
AVIATION...VFR CONDITIONS PREVAIL TODAY INTO TONIGHT WITH HIGH
PRESSURE CENTERED OVER NORTHWEST TEXAS. MID TO UPPER LEVEL
NORTHEAST FLOW WITH DRIER AIR TO LIMIT CLOUD COVER TO FEW-SCT. A
WEAKENING UPPER LOW PRESSURE TROUGH REMAINS CLOSE ENOUGH FOR
ISOLATED SHOWERS OR EVEN A THUNDERSTORM TO DEVELOP LATER THIS
AFTERNOON. LITTLE TO NO IMPACT ANTICIPATED AT THE 3 TERMINALS
SITE. LIGHT SOUTHEAST FLOW BECOMING MODERATE AS THE SEA BREEZE
MOVES EAST TO WEST BETWEEN 19-23Z
PREV DISCUSSION... /ISSUED 406 AM CDT FRI JUL 25 2014/
SHORT TERM /TODAY THROUGH SATURDAY/...WEAKENING 250MB SHEAR LINE
LIES ALONG THE TEXAS COAST WITH THE BASE OF THE TROUGH NOTED OVER
OUR WESTERN ZONES THIS MORNING. CENTER OF HOT RIDGE OVER THE TEXAS
PANHANDLE WITH DRIER NORTHEAST FLOW. WE SHOULD SEE A DECREASING
AREAL COVERAGE OF POPS AS THE DRIER AIR INFILTRATES THE REGION AND
THE AND THE TROUGH CONTINUES TO DAMPEN OUT. SPOTTY 20 PERCENT POPS
LOOK FAIR WITH A MORE TYPICAL SEA BREEZE DISTRIBUTION ANTICIPATED.
GRADIENT SLIGHTLY STRONGER TODAY WITH A STRONGER THERMAL LOW.
WINDS PICK UP MOSTLY LATER IN THE AFTERNOON AS THE SEA BREEZE
MOVES INLAND. TEMPERATURES REMAIN ABOVE NORMAL BUT JUST SLIGHTLY
DOWN A DEGREE OR TWO IN THE EAST AS THE SEA BREEZE COMES THROUGH A
BIT EARLIER.
TONIGHT...WARM AND MUGGY AND POSSIBLE A DEGREE WARM IF WINDS STAY UP
PASS MIDNIGHT.
SATURDAY...THE SHEAR LINE IS PRETTY MUCH LOST IN THE STRONGER
NORTHEAST FLOW AROUND THE RIDGE. MEAN RH LOWERS AND 850MB
TEMPERATURES RISE KEEPING RAIN CHANCES BELOW 10 PERCENT. EXPECT
AMBIENT TEMPERATURES TO PEAK ANOTHER DEGREE OR SO WITH LESS CLOUDS
AND LOWER RH. AFTERNOON BREEZES TO MAKE THE HEAT A BIT MORE
TOLERABLE.
LONG TERM /SATURDAY NIGHT THROUGH THURSDAY/...H5 RIDGE CONTINUES
TO DOMINATE THE LOCAL WEATHER INTO THE MIDDLE OF NEXT
WEEK...KEEPING TEMPERATURES ABOVE NORMAL. THICKNESS VALUES REMAIN
STABLE AND ATMOSPHERIC MOISTURE REMAIN WELL BELOW NORMAL THROUGH
MIDWEEK...WHICH WILL KEEP A CONSISTENT TEMPERATURE REGIME. HIGHS
WILL BE IN THE MID TO UPPER 90S ALONG THE COAST AND 100 TO 105 FOR
THE WESTERN AREAS. HEAT INDEX VALUES WILL REACH 105 TO 110
AREAWIDE EACH AFTERNOON. PW VALUES REMAIN AT OR BELOW 1.5 INCHES
INTO NEXT WEEK...WITH NO RAIN CHANCES AND EVEN MINIMAL CLOUD
COVER. FAR EXTENDED MODELS ARE BEGINNING TO INDICATE THE THE RIDGE
WILL FINALLY DISPLACE SOUTHWARD AS THE EASTERN TROUGH MAKES AN
UNUSUALLY FAR SOUTHWARD DRIVE. AN ACCOMPANYING COLD FRONT MAY
DRIVE INTO TEXAS AGAIN...WITH A POSSIBLE RETURN OF RAIN CHANCES
FOR THE FIRST WEEKEND IN AUGUST.
MARINE...
TODAY THROUGH SATURDAY...PRESSURE GRADIENT TO SLOWLY STRENGTHEN
LATER TODAY INTO SATURDAY. INTERACTION BETWEEN THE SURFACE RIDGE
OVER THE GULF AND THERMAL LOW PRESSURE INLAND TO PROVIDE THE
SLIGHTLY STRONGER WINDS INTO SATURDAY. WINDS STILL REMAIN LOW
ENOUGH WITH NO MENTION OF EXERCISE CAUTION OR ANY ADVISORIES.
STILL A FEW SHOWERS OVER THE OFFSHORE COASTAL WATERS THIS MORNING
BECOMING EVEN MORE ISOLATED THIS AFTERNOON AND TONIGHT.
SATURDAY NIGHT THROUGH MONDAY...MODEST SOUTHEAST WINDS CONTINUE
FOR THE LATTER HALF OF THE WEEKEND INTO EARLY NEXT WEEK AS THE
GULF RIDGE REMAINS FIRM AND THE HEAT LOW FLUCTUATES ACROSS WEST
TEXAS. ADVISORIES ARE NOT EXPECTED...BUT CAUTION MAY BE ADVISED
FOR THE LAGUNA SUNDAY AND MONDAY. LONG FETCH ACROSS THE GULF
BEGINS TO BUILD SEAS TO 3 TO 4 FEET EARLY NEXT WEEK.
&&
.PRELIMINARY POINT TEMPS/POPS...
BAYVIEW/PORT ISABEL 95 80 95 80 / 10 10 10 10
BROWNSVILLE 96 78 97 79 / 20 10 10 10
HARLINGEN 99 76 100 79 / 20 10 10 10
MCALLEN 100 78 100 79 / 20 10 10 10
RIO GRANDE CITY 102 79 102 78 / 20 10 10 10
SOUTH PADRE ISLAND 91 80 91 81 / 10 20 20 10
&&
.BRO WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
GM...NONE.
&&
$$
THIS PRODUCT IS ALSO AVAILABLE ON THE WEB AT:
HTTP://WEATHER.GOV/RGV
SHORT TERM FORECASTER... BUTTS
LONG TERM FORECASTER... TOMASELLI
PSU/GRAPHICASTS... CAMPBELL
AREA FORECAST DISCUSSION
NWS GREEN BAY WI
1047 PM CDT SAT JUL 26 2014
UPDATED AVIATION PORTION FOR 06Z TAF ISSUANCE
.SYNOPSIS...
ISSUED AT 236 PM CDT SAT JUL 26 2014
SCATTERED SHOWERS AND THUNDERSTORMS FOR THE REST OF THE WEEKEND...
THEN MUCH COOLER EARLY NEXT WEEK.
MAJOR AMPLIFICATION OF THE LNGWV PATTERN INVOF NOAM WILL OCCUR
THE NEXT COUPLE DAYS AS CLOSED UPR LOW CURRENTLY OVER THE LAKE
WINNIPEG REGION SHIFTS E AND THEN TURNS SE. IN ADDITION TO THE
RESULTING UPR TROF OVER THE LOWER GREAT LAKES RGN...ANOTHER LNGWV
TROF WL BE OFF THE BRITISH COLUMBIA COAST...AND A STG RIDGE WL BE
ANCHORED OVER THE INTERMOUNTAIN WEST. THE DEVELOPING PATTERN WL BE
VERY STABLE. ONCE IN PLACE...IT WILL REMAIN IN PLACE THROUGH THE
REMAINDER OF THE FCST PERIOD. BUT GRADUAL MODIFICATION OF THE COLD
AIR WITHIN THE TROFS WL ALLOW THE FLOW ACRS THE CONUS TO
WEAKEN...AND THE MAIN WESTERLIES TO REFORM BACK N ACRS CANADA.
WARM AND HUMID CONDITIONS AT THE START OF THE FCST PERIOD WL
QUICKLY BE REPLACED BY MUCH COOLER AND DRIER CONDITIONS FOR THE
START OF THE WORK WEEK. THEN TEMPERATURES WL GRADUALLY REBOUND
BACK TO SEASONAL NORMALS AS THE COOL AIR ACRS THE REGION
MODIFIES.
THE BEST CHC FOR SIG PCPN WL BE EARLY IN THE FCST PERIOD...AS THE
UPR LOW CROSSES THE RGN. BUT THE COVERAGE OF THE SIG PCPN WITH
THE UPR LOW IS LIKELY TO BE SCT...AND THE GENERAL NWLY UPR FLOW
THAT WL DOMINATE THE AREA FOR THE REMAINDER OF THE PERIOD FAVORS
BLO NORMAL PCPN AMNTS. THE LACK OF PCPN ACRS MUCH OF THE AREA THE
PAST FEW WEEKS IS BECOMING APPARENT IN THE FORM OF BROWN LAWNS AND
SLUGGISH GROWTH OF CROPS IN AREA FARMS. PCPN TOTALS FOR THE PAST
30 DAYS HAVE GENERALLY ONLY BEEN 25-50 PCT OF NORMAL ACRS MOST OF
THE FCST AREA. OVER THE PAST COUPLE WEEKS...THE MOST SIG PCPN
DEFICIT HAS BEEN OVER E-C WI...WHERE PCPN TOTALS HAVE BEEN LESS
THAN 25 PCT OF NORMAL.
&&
.SHORT TERM...TONIGHT AND SUNDAY
ISSUED AT 236 PM CDT SAT JUL 26 2014
THE LATEST RAP ANALYSIS AND SATELLITE/RADAR IMAGERY SHOW A WEAK AREA
OF LOW PRESSURE MOVING EAST OVER LAKE SUPERIOR AND SURFACE TROUGH
AXIS EXTENDING SOUTHWEST FROM THIS SURFACE LOW ACROSS NORTHWEST
WISCONSIN. A BROKEN LINE OF THUNDERSTORMS HAVE DEVELOP ALONG THIS
TROUGH AXIS OVER THE CENTRAL UPPER PENINSULA BUT THINK THEY WILL
REMAIN NORTH OF THE BORDER FOR THE REST OF THE AFTERNOON. THOUGH
LOW STRATUS REMAINS AHEAD OF THE TROUGH OVER NORTHEAST
WISCONSIN...CLEARING SKIES HAVE MOVED INTO NORTH-CENTRAL WISCONSIN
WHERE MIXING HAS DROPPED DEWPOINTS INTO THE LOWER AND MIDDLE 50S. AN
AREA OF CIRRUS WILL CONTINUE TO MOVE EAST OVER CENTRAL AND
EAST-CENTRAL WISCONSIN THIS AFTERNOON FROM THUNDERSTORMS OVER THE
CENTRAL PLAINS. OTHERWISE...THE FOCUS FOR THE NEXT 24 HOURS WILL
REVOLVE AROUND THE UPPER LOW OVER SOUTH-CENTRAL CANADA. AS IT MOVES
SOUTHEAST...THE POTENTIAL FOR STRONG TO SEVERE THUNDERSTORMS IS THE
MAIN FORECAST CONCERN LATE TONIGHT INTO SUNDAY.
TONIGHT...THE UPPER LEVEL LOW AND ASSOCIATED OCCLUDED FRONT WILL
DIVE SOUTHEAST INTO NORTHWEST AND NORTH-CENTRAL RESPECTIVELY BY LATE
TONIGHT. AHEAD OF THESE FEATURES...MODELS DEPICT A RELATIVELY
NARROW RIBBON OF HIGHER THETAE ABOVE THE NOCTURNAL INVERSION THAT
MOVES INTO N-C WISCONSIN BY 09Z AND THE FOX VALLEY TO IRON MOUNTAIN
CORRIDOR BY 12Z. WITHIN THIS THETAE RIBBON...MODELS ESTIMATE
ELEVATED CAPES BETWEEN 500-1000 J/KG WHICH SUPPORTS A CHANCE OF
THUNDERSTORMS. QG FORCING WILL BE INCREASING AT THE SAME TIME AND
PWATS WILL BE NEARING 1.5 INCHES. SO WILL SHOW PRECIP CHANCES IN
THE LIKELY RANGE OVER NORTH-CENTRAL WISCONSIN AFTER MIDNIGHT WITHIN
THE DEFORMATION ZONE AND A CHANCE ELSEWHERE. IF STORMS DO
DEVELOP...SOME COULD CONTAIN SUB-SEVERE SIZED HAIL. EFFECTIVE
SHEARS 20-25 KNOTS SUGGESTS SEVERE STORMS ARE UNLIKELY.
SUNDAY...THE UPPER LOW WILL MOVE ACROSS OUR AREA DURING THE MORNING
AND EXIT OVER SOUTHERN LAKE MICHIGAN BY LATE IN THE AFTERNOON.
BENEATH THE UPPER LOW...AMPLE MOISTURE COMBINED WITH STEEP LOW LEVEL
LAPSE RATES WILL LEAD TO THE DEVELOPMENT OF SHOWERS AND A FEW
THUNDERSTORMS BY LATE IN THE MORNING. WET BULB ZERO TEMPS BELOW
10KFT WILL PROVIDE A THREAT OF HAIL WITHIN ANY THUNDERSTORMS AND
WOULD NOT BE SURPRISED IF AN ISOLATED STORM OR TWO APPROACHES SEVERE
LIMITS. WILL KEEP THIS MENTION IN THE HWO. HIGHS COOLING TO THE
MIDDLE 60S NORTH TO MIDDLE 70S SOUTH.
.LONG TERM...SUNDAY NIGHT THROUGH SATURDAY
ISSUED AT 236 PM CDT SAT JUL 26 2014
PCPN WITH THE DEPARTING UPR LOW COULD LINGER INTO SUN EVE...ESP
IN THE EAST. MAINTAINED CHC POPS FOR THE EVENING. ALTHOUGH IT/S
NOT OUT OF THE QUESTION THAT SOMETHING COULD LINGER PAST
MIDNIGHT...THERE WAS NOT ENOUGH SUPPORT FOR THAT TO DRAG POPS
THROUGH THE WHOLE NIGHT. SINCE WINDS WL LIKELY STAY UP DURING THE
NGT AND COOLER AIR WL FIRST BE WORKING INTO THE AREA...EDGED MINS
TOWARD A BLEND OF THE WARMER GUIDANCE PRODUCTS.
THE FCST AREA WL STILL BE ON THE CYCLONIC SIDE OF THE UPR JET
MON...SO ANY SML SCALE DISTURBANCE THAT WORKS ACRS THE AREA
DURING THE AFTN COULD EASILY GENERATE ISOLD-SCT SHRA. BUT WITH NO
FORCING APPARENT ON THE MODELS ATTM...KEPT FCST DRY. IT LOOKS LIKE
A DISTURBANCE WL DROP SWD ACRS THE AREA TUE...SO KEPT CHC POPS AT
THAT TIME.
SIG MOISTURE WL REMAIN WELL S OF THE AREA FOR THE REST OF THE
FCST PERIOD...SO THE PROSPECT FOR SIG WIDESPREAD PCPN DOES NOT
LOOK GOOD. BUT THERE WL STILL BE AMPLE OPPORTUNITIES FOR SCT LGT
PCPN AS SML SCALE SHRTWVS DROP SEWD ACRS THE AREA. CONFIDENCE IN
THE TIMING THOSE CHCS DIMINISHES RAPIDLY AS ONE GOES FARTHER OUT
INTO THE FCST.
NO SIG CHGS WERE NEEDED TO THE BROAD-BASED EXTENDED FCST
INITIALIZATION GRIDS.
&&
.AVIATION...FOR 06Z TAF ISSUANCE
ISSUED AT 1040 PM CDT SAT JUL 26 2014
AN UPPER LEVEL LOW WILL DROP SOUTHEAST INTO NORTHERN WISCONSIN
OVERNIGHT INTO SUNDAY MORNING. A BROKEN LINE OF SHOWERS AND A FEW
THUNDERSTORMS ARE CURRENTLY MOVING THROUGH WEST CENTRAL WI
ASSOCIATED WITH A TROF OF LOW PRESSURE AT THE SURFACE. PLENTY OF
INSTABILITY ALOFT TO MAINTAIN SOME OF THE SHOWERS/STORMS AS THEY
MOVE EAST OVERNIGHT. WIDESPREAD SHOWERS AND SCATTERED
THUNDERSTORMS ARE LIKELY TO DEVELOP SUNDAY MORNING WITH LOWERING
CIGS. KEPT THUNDER OUT OF TAFS AT THIS TIME GIVEN EXPECTED
ISOLATED TO SCATTERED COVERAGE.
&&
.GRB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS.......SKOWRONSKI
SHORT TERM.....MPC
LONG TERM......SKOWRONSKI
AVIATION.......TE
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
905 PM CDT SAT JUL 26 2014
.UPDATE...
ISSUED AT 904 PM CDT SAT JUL 26 2014
THUNDERSTORMS CONTINUE IN NORTHWEST WISCONSIN WITH AN INCREASE
SEEN OVER THE PAST HOUR SOUTH OF HAYWARD. THE SOUTHERNMOST STORM
IS MOVING A BIT TO THE RIGHT OF THE MEAN FLOW AND IS TAKING AIM ON
TAYLOR COUNTY NOW AROUND 11 PM. HAIL OF 2.75 INCHES WAS RECEIVED
FROM THIS STORM AT 847PM.
STORMS CONTINUE TO MAINTAIN INTENSITY IN THE MOISTURE AND
INSTABILITY AXIS CURRENTLY RUNNING FROM SOUTHCENTRAL MN THROUGH
KMSP TO HAYWARD. THIS IS THE LOW-LEVEL MOISTURE PLUME AXIS WHERE
2000 J/KG MUCAPE AND LITTLE CAP CONTINUES. WHILE SOME CONVERGENCE
AND TROUGHING IS ALONG THE STORM AXIS IN THE LOW-LEVELS...THE
INITIAL QG FORCING FROM THE DEEPER LOW NW OF KINL IS PROVIDING A
MORE FAVORABLE LIFT ENVIRONMENT FROM I-94 AND NORTH. THIS WOULD
TEND TO FAVOR AN ISOLATED LARGE HAIL STORM TONIGHT NEAR AND NORTH
OF I-94.
FURTHER SOUTH /KMSP AND SOUTH/ MORE ISOLATED STORMS COULD POP UP
WITH INSTABILITY AND WEAK CONVERGENCE IN THE LOW- LEVELS SOUTH TO
ST JAMES. HRRR IS CONSISTENT IN ITS SIGNALS OF SCT SHOWERS AND
ISOLATED TSRA DEVELOPING EAST THROUGH THE OVERNIGHT ALONG THE NEAR
SURFACE CONVERGENCE LINE AND CAPE AXIS. HAVE SOME DOUBTS ABOUT
STORMS MAINTAINING IN SUCH WEAK SURFACE CONVERGENCE SOUTH OF I-94.
OVERNIGHT...THIS WEAK CONVERGENCE/FRONT SLIDES EAST AND EXITS
CENTRAL AND SWRN WI AROUND 10Z. WITH DEEPER SHEAR IN SUPERCELL
RANGE...AND INSTABILITY REMAINING UP OVERNIGHT IN LOW-LEVEL
MOISTURE AXIS...CANNOT RULE OUT A SEVERE STORM SOUTHWEST OF I-94.
LARGE HAIL IS THE MAIN THREAT OVERNIGHT.
&&
.SHORT TERM...(TONIGHT THROUGH SUNDAY NIGHT)
ISSUED AT 200 PM CDT SAT JUL 26 2014
WATER VAPOR IMAGERY SHOWING A CLOSED LOW OVER SOUTHERN MANITOBA
CANADA WITH A FAIRLY HIGH ZONAL FLOW ACROSS THE NORTHERN TIER OF THE
CONUS. FAIRLY STRONG 850-500MB FRONTOGENESIS WAS PRODUCING A
SCATTERED BAND OF SHOWERS/ISOLATED THUNDERSTORMS ALONG AND SOUTH OF
THE I-90 CORRIDOR FROM THE MISSISSIPPI RIVER...BACK TO NEAR SIOUX
FALLS SD. DESPITE THICK CLOUD COVER ACROSS THE ARX FORECAST AREA...
TEMPERATURES WERE IN THE UPPER 70S/LOWER 80S. WITH DEW POINTS IN THE
60S/LOWER 70S...RATHER MUGGY CONDITIONS WERE ALSO IN PLACE.
RAP SHOWS BAND OF 850-500MB FRONTOGENESIS WEAKENING/SAGGING SOUTH
OUT OF THE AREA INTO IL BY EARLY THIS EVENING...TAKING
SHOWERS/ISOLATED THUNDERSTORMS WITH IT. FOCUS THEN TURNS TO THAT
CLOSED LOW DROPPING SOUTHEAST OUT OF SOUTHERN MANITOBA INTO NORTHERN
MN/WI TONIGHT. STRONG 700-300MB PV-ADVECTION/QG-RESPONSE ASSOCIATED
WITH THIS WAVE ALONG WITH STEEPENING MID-LEVEL LAPSE RATES. THIS
WILL PRODUCE SCATTERED SHOWERS AND THUNDERSTORMS NORTH OF I-94 THIS
EVENING INTO EARLY SUNDAY MORNING. IN FACT...NAM INDICATES ELEVATED
MUCAPE IN THE 850-300MB LAYER OF 1500-1800J/KG ALONG WITH BULK SHEAR
IN THE 25-45KT RANGE. WILL THEREFORE HAVE TO KEEP AN EYE ON THE
POSSIBILITY OF A FEW STRONGER STORMS WITH LARGER HAIL/WIND
POTENTIAL. OTHERWISE...LOOK FOR LOWS TONIGHT IN THE UPPER 50S TO THE
MIDDLE 60S.
THE LIKELIHOOD OF SHOWERS AND ISOLATED THUNDERSTORMS WILL CONTINUE
THROUGH SUNDAY AS THE CLOSED LOW DRIFTS SOUTHEAST ACROSS THE REGION.
COOLER BREEZY CONDITIONS WILL ALSO BE SEEN WITH HIGHS ONLY TOPPING
OFF IN THE 70-80 DEGREE RANGE AS NORTHWEST WINDS BLOW AT 10 TO 20
MPH.
FOR SUNDAY NIGHT...PLAN ON SHOWERS TAPERING OFF RAPIDLY FROM WEST TO
EAST WITH A FEW EVENING SHOWERS LINGERING ACROSS CENTRAL WI THROUGH
9 PM. OTHERWISE...SURFACE HIGH PRESSURE BUILDING IN FROM THE
NORTHERN PLAINS WILL PRODUCE A DIMINISHING TREND TO THE CLOUDS WITH
OVERNIGHT TEMPERATURES DROPPING INTO THE UPPER 40S/LOWER 50S ACROSS
CENTRAL WI...TO THE MIDDLE 50S ELSEWHERE.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 200 PM CDT SAT JUL 26 2014
COOLER AND DRIER CONDITIONS WILL FILTER INTO THE AREA MONDAY/MONDAY
NIGHT AS HIGH PRESSURE ESTABLISHES ITSELF ACROSS THE UPPER
MISSISSIPPI RIVER REGION. LOOK FOR HIGHS MONDAY IN THE LOWER/MIDDLE
70S AND LOWS MONDAY NIGHT IN THE UPPER 40S ACROSS THE
SANDY/CRANBERRY BOG AREAS OF CENTRAL WI...TO THE LOWER/MIDDLE 50S
ELSEWHERE.
A FEW SHOWERS MAY SNEAK INTO PORTIONS OF EASTERN/CENTRAL WI ON
TUESDAY AS THE MODELS BRING ANOTHER WEAK MID-LEVEL TROUGH SOUTHWARD
THROUGH THE REGION. HIGHS TUESDAY LOOK TO BE IN THE MID/UPPER 70S.
COOLER CYCLONIC FLOW ALOFT CONTINUES THROUGH THE REMAINDER OF THE
PERIOD WITH CHANCES OF MAINLY DAYTIME HEATING SHOWERS/ISOLATED
THUNDERSTORMS. OTHERWISE...LOOK FOR HIGHS IN THE 75-80 DEGREE RANGE
WITH LOWS IN THE MIDDLE 50S TO LOWER 60S. THESE TEMPERATURE ARE MORE
TYPICAL OF EARLY SEPTEMBER.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z SUNDAY EVENING)
ISSUED AT 700 PM CDT SAT JUL 26 2014
AN UNUSUALLY DEEP AND COOL WEATHER SYSTEM WILL SHIFT INTO THE
MIDWEST OVERNIGHT AND PROVIDE MVFR CIGS SUNDAY. SHOWERS WILL BE
MORE WIDESPREAD FURTHER EAST /WI/ AND THUS SHRA WAS INCLUDED IN
THE KLSE TAF. THE WINDS WILL ALSO BE GUSTY FROM THE NORTHWEST
SUNDAY...UP TO 30KTS. THERE ARE SOME SMALL TSRA CHANCES TO THE
NORTH OF THE AIRFIELDS THIS EVENING...BUT VFR CONDITIONS ARE
EXPECTED.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
UPDATE...BAUMGARDT
SHORT TERM...DAS
LONG TERM...DAS
AVIATION...BAUMGARDT
AREA FORECAST DISCUSSION
NWS GREEN BAY WI
647 PM CDT SAT JUL 26 2014
UPDATED AVIATION PORTION FOR 00Z TAF ISSUANCE
.SYNOPSIS...
ISSUED AT 236 PM CDT SAT JUL 26 2014
SCATTERED SHOWERS AND THUNDERSTORMS FOR THE REST OF THE WEEKEND...
THEN MUCH COOLER EARLY NEXT WEEK.
MAJOR AMPLIFICATION OF THE LNGWV PATTERN INVOF NOAM WILL OCCUR
THE NEXT COUPLE DAYS AS CLOSED UPR LOW CURRENTLY OVER THE LAKE
WINNIPEG REGION SHIFTS E AND THEN TURNS SE. IN ADDITION TO THE
RESULTING UPR TROF OVER THE LOWER GREAT LAKES RGN...ANOTHER LNGWV
TROF WL BE OFF THE BRITISH COLUMBIA COAST...AND A STG RIDGE WL BE
ANCHORED OVER THE INTERMOUNTAIN WEST. THE DEVELOPING PATTERN WL BE
VERY STABLE. ONCE IN PLACE...IT WILL REMAIN IN PLACE THROUGH THE
REMAINDER OF THE FCST PERIOD. BUT GRADUAL MODIFICATION OF THE COLD
AIR WITHIN THE TROFS WL ALLOW THE FLOW ACRS THE CONUS TO
WEAKEN...AND THE MAIN WESTERLIES TO REFORM BACK N ACRS CANADA.
WARM AND HUMID CONDITIONS AT THE START OF THE FCST PERIOD WL
QUICKLY BE REPLACED BY MUCH COOLER AND DRIER CONDITIONS FOR THE
START OF THE WORK WEEK. THEN TEMPERATURES WL GRADUALLY REBOUND
BACK TO SEASONAL NORMALS AS THE COOL AIR ACRS THE REGION
MODIFIES.
THE BEST CHC FOR SIG PCPN WL BE EARLY IN THE FCST PERIOD...AS THE
UPR LOW CROSSES THE RGN. BUT THE COVERAGE OF THE SIG PCPN WITH
THE UPR LOW IS LIKELY TO BE SCT...AND THE GENERAL NWLY UPR FLOW
THAT WL DOMINATE THE AREA FOR THE REMAINDER OF THE PERIOD FAVORS
BLO NORMAL PCPN AMNTS. THE LACK OF PCPN ACRS MUCH OF THE AREA THE
PAST FEW WEEKS IS BECOMING APPARENT IN THE FORM OF BROWN LAWNS AND
SLUGGISH GROWTH OF CROPS IN AREA FARMS. PCPN TOTALS FOR THE PAST
30 DAYS HAVE GENERALLY ONLY BEEN 25-50 PCT OF NORMAL ACRS MOST OF
THE FCST AREA. OVER THE PAST COUPLE WEEKS...THE MOST SIG PCPN
DEFICIT HAS BEEN OVER E-C WI...WHERE PCPN TOTALS HAVE BEEN LESS
THAN 25 PCT OF NORMAL.
&&
.SHORT TERM...TONIGHT AND SUNDAY
ISSUED AT 236 PM CDT SAT JUL 26 2014
THE LATEST RAP ANALYSIS AND SATELLITE/RADAR IMAGERY SHOW A WEAK AREA
OF LOW PRESSURE MOVING EAST OVER LAKE SUPERIOR AND SURFACE TROUGH
AXIS EXTENDING SOUTHWEST FROM THIS SURFACE LOW ACROSS NORTHWEST
WISCONSIN. A BROKEN LINE OF THUNDERSTORMS HAVE DEVELOP ALONG THIS
TROUGH AXIS OVER THE CENTRAL UPPER PENINSULA BUT THINK THEY WILL
REMAIN NORTH OF THE BORDER FOR THE REST OF THE AFTERNOON. THOUGH
LOW STRATUS REMAINS AHEAD OF THE TROUGH OVER NORTHEAST
WISCONSIN...CLEARING SKIES HAVE MOVED INTO NORTH-CENTRAL WISCONSIN
WHERE MIXING HAS DROPPED DEWPOINTS INTO THE LOWER AND MIDDLE 50S. AN
AREA OF CIRRUS WILL CONTINUE TO MOVE EAST OVER CENTRAL AND
EAST-CENTRAL WISCONSIN THIS AFTERNOON FROM THUNDERSTORMS OVER THE
CENTRAL PLAINS. OTHERWISE...THE FOCUS FOR THE NEXT 24 HOURS WILL
REVOLVE AROUND THE UPPER LOW OVER SOUTH-CENTRAL CANADA. AS IT MOVES
SOUTHEAST...THE POTENTIAL FOR STRONG TO SEVERE THUNDERSTORMS IS THE
MAIN FORECAST CONCERN LATE TONIGHT INTO SUNDAY.
TONIGHT...THE UPPER LEVEL LOW AND ASSOCIATED OCCLUDED FRONT WILL
DIVE SOUTHEAST INTO NORTHWEST AND NORTH-CENTRAL RESPECTIVELY BY LATE
TONIGHT. AHEAD OF THESE FEATURES...MODELS DEPICT A RELATIVELY
NARROW RIBBON OF HIGHER THETAE ABOVE THE NOCTURNAL INVERSION THAT
MOVES INTO N-C WISCONSIN BY 09Z AND THE FOX VALLEY TO IRON MOUNTAIN
CORRIDOR BY 12Z. WITHIN THIS THETAE RIBBON...MODELS ESTIMATE
ELEVATED CAPES BETWEEN 500-1000 J/KG WHICH SUPPORTS A CHANCE OF
THUNDERSTORMS. QG FORCING WILL BE INCREASING AT THE SAME TIME AND
PWATS WILL BE NEARING 1.5 INCHES. SO WILL SHOW PRECIP CHANCES IN
THE LIKELY RANGE OVER NORTH-CENTRAL WISCONSIN AFTER MIDNIGHT WITHIN
THE DEFORMATION ZONE AND A CHANCE ELSEWHERE. IF STORMS DO
DEVELOP...SOME COULD CONTAIN SUB-SEVERE SIZED HAIL. EFFECTIVE
SHEARS 20-25 KNOTS SUGGESTS SEVERE STORMS ARE UNLIKELY.
SUNDAY...THE UPPER LOW WILL MOVE ACROSS OUR AREA DURING THE MORNING
AND EXIT OVER SOUTHERN LAKE MICHIGAN BY LATE IN THE AFTERNOON.
BENEATH THE UPPER LOW...AMPLE MOISTURE COMBINED WITH STEEP LOW LEVEL
LAPSE RATES WILL LEAD TO THE DEVELOPMENT OF SHOWERS AND A FEW
THUNDERSTORMS BY LATE IN THE MORNING. WET BULB ZERO TEMPS BELOW
10KFT WILL PROVIDE A THREAT OF HAIL WITHIN ANY THUNDERSTORMS AND
WOULD NOT BE SURPRISED IF AN ISOLATED STORM OR TWO APPROACHES SEVERE
LIMITS. WILL KEEP THIS MENTION IN THE HWO. HIGHS COOLING TO THE
MIDDLE 60S NORTH TO MIDDLE 70S SOUTH.
.LONG TERM...SUNDAY NIGHT THROUGH SATURDAY
ISSUED AT 236 PM CDT SAT JUL 26 2014
PCPN WITH THE DEPARTING UPR LOW COULD LINGER INTO SUN EVE...ESP
IN THE EAST. MAINTAINED CHC POPS FOR THE EVENING. ALTHOUGH IT/S
NOT OUT OF THE QUESTION THAT SOMETHING COULD LINGER PAST
MIDNIGHT...THERE WAS NOT ENOUGH SUPPORT FOR THAT TO DRAG POPS
THROUGH THE WHOLE NIGHT. SINCE WINDS WL LIKELY STAY UP DURING THE
NGT AND COOLER AIR WL FIRST BE WORKING INTO THE AREA...EDGED MINS
TOWARD A BLEND OF THE WARMER GUIDANCE PRODUCTS.
THE FCST AREA WL STILL BE ON THE CYCLONIC SIDE OF THE UPR JET
MON...SO ANY SML SCALE DISTURBANCE THAT WORKS ACRS THE AREA
DURING THE AFTN COULD EASILY GENERATE ISOLD-SCT SHRA. BUT WITH NO
FORCING APPARENT ON THE MODELS ATTM...KEPT FCST DRY. IT LOOKS LIKE
A DISTURBANCE WL DROP SWD ACRS THE AREA TUE...SO KEPT CHC POPS AT
THAT TIME.
SIG MOISTURE WL REMAIN WELL S OF THE AREA FOR THE REST OF THE
FCST PERIOD...SO THE PROSPECT FOR SIG WIDESPREAD PCPN DOES NOT
LOOK GOOD. BUT THERE WL STILL BE AMPLE OPPORTUNITIES FOR SCT LGT
PCPN AS SML SCALE SHRTWVS DROP SEWD ACRS THE AREA. CONFIDENCE IN
THE TIMING THOSE CHCS DIMINISHES RAPIDLY AS ONE GOES FARTHER OUT
INTO THE FCST.
NO SIG CHGS WERE NEEDED TO THE BROAD-BASED EXTENDED FCST
INITIALIZATION GRIDS.
&&
.AVIATION...FOR 00Z TAF ISSUANCE
ISSUED AT 626 PM CDT SAT JUL 26 2014
SKIES HAVE CLEARED OVER MUCH OF NORTHERN WI WITH ONLY SOME CIRRUS
MOVING IN AHEAD OF STORMS OVER NORTHERN MN. AN UPPER LEVEL LOW
WILL DROP SOUTHEAST INTO NORTHERN WISCONSIN OVERNIGHT INTO SUNDAY
MORNING. SPOTTY SHOWERS AND A FEW THUNDERSTORMS ARE POSSIBLE AHEAD
OF THIS SYSTEM OVERNIGHT...MAINLY AFTER 3Z AS ONGOING ACTIVITY IN
MN MOVES EAST. WIDESPREAD SHOWERS AND SCATTERED THUNDERSTORMS
ARE LIKELY TO DEVELOP BY SUNDAY MORNING ALONG WITH LOWERING CIGS.
KEPT THUNDER OUT OF TAFS AT THIS TIME GIVEN EXPECTED SCATTERED
COVERAGE. &&
.GRB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS.......SKOWRONSKI
SHORT TERM.....MPC
LONG TERM......SKOWRONSKI
AVIATION.......TE
FORECAST DISCUSSION FOR ROUTINE AFTERNOON FORECAST ISSUANCE
.SHORT TERM...TONIGHT AND SATURDAY
ISSUED AT 227 PM CDT FRI JUL 25 2014
LATEST RAP ANALYSIS AND SATELLITE/RADAR IMAGERY SHOW HIGH PRESSURE
LOCATED OVER THE EASTERN U.S. AND A TROUGH OF LOW PRESSURE OVER THE
NORTHERN PLAINS. BETWEEN THESE FEATURES...WARM AIR AND MOISTURE
ADVECTION IS ONGOING IN THE LOW AND MID-LEVELS. THIS WEAK FORCING
COMBINED WITH ONE SHORTWAVE OVER EASTERN WISCONSIN AND ANOTHER OVER
NORTH-CENTRAL WISCONSIN HAS CONTRIBUTED TO SPOTTY SHOWER ACTIVITY
OVER THE COURSE OF THE DAY. SHOWERS ARE MAINLY CONFINED TO N-C
WISCONSIN CURRENTLY AS SHOWERS WITH THE EASTERN WISCONSIN SHORTWAVE
HAVE PUSHED SOUTH OF THE AREA. LOOKING UPSTREAM...SCT TO BKN STRATO
CU EXISTS ALL THE WAY INTO THE EASTERN DAKOTAS WHERE DEWPOINTS ARE
PUSHING INTO THE MIDDLE AND UPPER 60S. AS THIS MOISTURE RICH AIR
SPREADS EAST...SMALL SHOWER CHANCES AND CLOUDS ARE THE MAIN FORECAST
CONCERNS.
TONIGHT...AS ONE SHORTWAVE EXITS SOUTHEAST WISCONSIN EARLY THIS
EVENING...ANOTHER WAVE WILL BE DIVING SOUTHEAST OVER NORTHEAST
WISCONSIN. UNTIL THIS WAVE EXITS...WILL LEAVE AT LEAST AN ISOLATED
MENTION OF SHOWERS OVER N-C AND NORTHEAST WISCONSIN UNTIL LATE IN
THE EVENING. THEREAFTER...THOUGH WEAK THETAE ADVECTION WILL STILL
BE OCCURRING IN THE LOW LEVELS...MODELS SHOW MID-LEVEL MOISTURE
DEPARTING BEHIND THE SHORTWAVE AND A DECENT CAP DEVELOPING AROUND
700MB. SO THINK SMALL PRECIP CHANCES WILL END BY LATE IN THE
EVENING...AND THEN GO DRY THE REST OF THE NIGHT. SURFACE DEWPOINTS
WILL BE INCREASING HOWEVER...AND WITH NOCTURNAL COOLING...LOW
STRATUS SHOULD REMAIN RELATIVELY WIDESPREAD AND LOWER THROUGH THE
NIGHT. THIS WILL MAKE FOR A WARMER AND MUGGIER NIGHT THAN THE PAST
FEW WITH LOWS IN THE LOW TO MID 60S.
SATURDAY...AREAS OF STRATUS WILL LINGER INTO THE MORNING HOURS.
WITH DAYTIME HEATING...MIXING SHOULD BE ABLE TO TAP INTO THE DRY AIR
ABOVE THE INVERSION AND HELP TO DIMINISH THE CLOUDS FROM WEST TO
EAST OVER THE COURSE OF THE DAY. LOW LEVEL TEMPS ARE PROJECTED TO
BE QUIET TOASTY TOMORROW AND HAVE RAISED HIGHS A DEGREE OR TWO IN
MOST AREAS. HIGHS IN THE LOW TO MID 80S.
.LONG TERM...SATURDAY NIGHT THROUGH FRIDAY
ISSUED AT 227 PM CDT FRI JUL 25 2014
PCPN TRENDS FOR THE LATTER HALF OF THE WEEKEND...AND THE
POTENTIAL FOR SEVERE TSTMS ON SUNDAY AFTERNOON...WILL BE THE
MAIN FCST CHALLENGES.
MODELS ARE STILL TRYING TO FIND CONCENSUS ON THE TIMING OF THE
STRONG UPPER LEVEL TROF AND CANADIAN COLD FRONT ON SATURDAY NIGHT
AND SUNDAY. SLOWER IS USUALLY THE WAY TO GO WHEN DEALING WITH AN
UPPER LOW...SO HAVE LEANED TOWARD THE SLOWER ECMWF FOR THIS
SYSTEM. THIS WOULD SUGGEST A CHANCE OF TSTMS OVER THE NORTHWEST
THIRD OF GRB CWA AFTER MIDNIGHT SATURDAY NIGHT...THEN LIKELY POPS
SPREADING SE ACROSS THE FORECAST AREA ON SUNDAY. IF THE ECMWF
VERIFIES...ITS SLOWER MOVMT WOULD ALLOW FOR A LITTLE MORE HEATING
AND INSTABILITY IN ADVANCE OF THE SYSTEM...AND POTENTIALLY A
LITTLE GREATER THREAT OF SVR TSTMS OVER THE SE HALF OF THE
FORECAST AREA. MODIFIED FCST SOUNDINGS SUGGEST CAPE AROUND
1000-1500 J/KG...LI`S -3 TO -5...AND FAVORABLE WET BULB ZERO HGTS
OF 9.5-10K FT. DEEP LAYER SHEAR IS EXPECTED TO BE 25 TO 35 KTS
IN ADVANCE OF THE COLD FRONT AROUND MIDDAY...BUT SHOULD QUICKLY
WEAKEN AS THE UPPER TROF ARRIVES LATE IN THE DAY. ALTHOUGH A
SIGNIFICANT SVR WX EVENT IS NOT LIKELY DUE TO WIDESPREAD
CLOUDS/SHOWERS...WE CANNOT RULE OUT A FEW SVR TSTMS WITH LARGE
HAIL OVER PARTS OF NE/C/EC WI DURING THE AFTERNOON...SO WILL
CONTINUE TO MENTION THIS THREAT IN THE HWO.
THE EXTENDED FCST FOR THE UPCOMING WORK WEEK IS EXPECTED TO BE
AT OR A LITTLE COOLER THAN COOLER THAN NORMAL...WITH SCATTERED
SHOWERS AND TSTMS...MAINLY DURING THE AFTERNOONS AND EARLY
EVENINGS. A STRONG UPPER LEVEL RIDGE WILL BE SITUATED OVER THE
ROCKIES...WITH A LARGE UPPER TROF OVER THE EASTERN U.S. AND
EASTERN CANADA. ALTHOUGH S/W TROFS IN THE NW FLOW MAY GENERATE
SOME PCPN AT TIMES...IT APPEARS THAT MOST OF THE RAIN WILL BE
DIURNALLY-DRIVEN DUE TO DAYTIME HEATING/INSTABILITY.
&&
.AVIATION...FOR 18Z TAF ISSUANCE
ISSUED AT 1232 PM CDT FRI JUL 25 2014
INCREASING LOW LEVEL MOISTURE WILL BE WORKING NORTHEAST
ACROSS THE STATE THROUGH THE PERIOD. THOUGH THE CHANCES OF SHOWERS
WILL DIMINISH LATER THIS AFTERNOON WHEN A WEAK DISTURBANCE
EXITS...MVFR TO IFR CIGS/VSBYS ARE LIKELY TO DEVELOP GENERALLY AFTER
MIDNIGHT TONIGHT. RELATIVELY QUICK IMPROVEMENT TO THE CIGS/VSBYS
SHOULD OCCUR TOMORROW MORNING WITH DAYTIME HEATING AND MIXING.
&&
.GRB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM.....MPC
LONG TERM......KIECKBUSCH
AVIATION.......MPC
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
1247 PM CDT FRI JUL 25 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 303 AM CDT FRI JUL 25 2014
LATEST MOSAIC RADAR SHOWING A LINE OF SHOWERS AND THUNDERSTORMS
DEVELOPING FROM WEST CENTRAL MINNESOTA INTO CENTRAL IOWA EARLY
THIS MORNING. THE SHOWERS AND THUNDERSTORMS IS ON THE NOSE OF THE
LOW LEVEL JET/MOISTURE TRANSPORT AND CONVERGENCE IN THE 925-850MB
LAYER PER THE LATEST 25.03 RAP AND 25.00Z GFS/NAM.
THE 25.00Z NAM/GFS AND THE 25.03Z RAP INDICATE THE NOSE OF LOW LEVEL
JET/MOISTURE TRANSPORT AND CONVERGENCE WILL BE POINTED DIRECTLY INTO
MAINLY THE SOUTHERN FORECAST AREA THROUGH 18Z TODAY. HOWEVER...THE
MODELS SHOW THE CORFIDI VECTORS/UPWIND PROPAGATION VECTORS TO MOVE
THE SHOWERS AND THUNDERSTORMS SOUTH TO SOUTHEAST AND IMPACT MAINLY
THE SOUTHERN FORECAST AREA TODAY. THIS IS EVIDENT WITH MOVEMENT OF
THE THUNDERSTORMS EARLY THIS MORNING PER THE LATEST MOSAIC RADAR.
AT THIS TIME...SEVERE WEATHER THREAT LOOKS TO BE MINIMAL WITH THE
THUNDERSTORMS...AS THE LATEST 25.00Z NAM AND 25.03Z RAP SHOW 0-6KM
MOST UNSTABLE CAPE LESS THAN 1000 J/KG AND THE BETTER ELEVATED
INSTABILITY TO BE WEST OF THE DEVELOPING THUNDERSTORM
ACTIVITY/NOSE OF THE LOW LEVEL JET/MOISTURE CONVERGENCE. THE
MODELS SHOW PRECIPITABLE WATERS APPROACHING 1.5 TO 2 INCHES LATE
THIS MORNING. SOME OF THE THUNDERSTORMS COULD PRODUCE LOCAL HEAVY
RAINFALL.
THE LOW LEVEL JET/MOISTURE CONVERGENCE WEAKENS AND MOVES EAST OF
THE FORECAST AREA THIS AFTERNOON AND EVENING AND WILL ALLOW FOR
SKIES AND PRECIPITATION CHANCES TO DIMINISH WEST TO EAST ACROSS
THE FORECAST AREA.
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 303 AM CDT FRI JUL 25 2014
NEXT CONCERN IS CLOSED UPPER LEVEL LOW OVER SOUTHERN SASKATCHEWAN
AND ALBERTA SLOWLY MEANDERS OVER THE UPPER GREAT LAKES REGION
SATURDAY NIGHT INTO SUNDAY. THE 25.00Z GFS/NAM SHOW MUCH STRONGER
AND DEEPER QG FORCING IN ASSOCIATION WITH THE UPPER LEVEL LOW. BEST
FORCING INCREASES OVER THE NORTHERN PORTIONS OF FORECAST AREA LATE
SATURDAY NIGHT INTO SUNDAY...HENCE THE BETTER PRECIPITATION CHANCES.
THE NAM/GFS BUFKIT SOUNDINGS INDICATE WEAK ELEVATED CAPE MAINLY
ABOVE 800MB BY 18Z SUNDAY AND 0-6KM MOST UNSTABLE CAPE OF 500-1000
J/KG EAST OF THE MISSISSIPPI RIVER. WILL CONTINUE TO MENTION
ISOLATED THUNDERSTORMS SATURDAY NIGHT INTO SUNDAY.
SUNDAY NIGHT THROUGH THURSDAY...NORTHERLY FLOW DEVELOPS OVER THE
UPPER GREAT LAKES REGION PER LATEST 25.00Z GFS/ECMWF/GEM. MAIN
CONCERN IS TIMING OF THE WEAK SHORTWAVE TROUGHS EMBEDDED IN THE
NORTHERLY FLOW ALOFT AND PRODUCE SMALL PRECIPITATION CHANCES ACROSS
PARTS OF THE FORECAST AREA TUESDAY...WEDNESDAY NIGHT INTO
THURSDAY. TEMPERATURES MONDAY THROUGH THURSDAY WILL CONTINUE TO BE
UNSEASONABLY COOL ACROSS FORECAST AREA...AS THE 25.00Z GEFS
INDICATE 850MB TEMPERATURE ANOMALIES IN THE MINUS 0.5 TO MINUS 1.5
DEGREES CELSIUS RANGE.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON)
ISSUED AT 1247 PM CDT FRI JUL 25 2014
BROKEN MVFR CEILINGS WILL SLOWLY LIFT AND SCATTER OUT THIS
AFTERNOON...INITIALLY AT KRST AND LIKELY TOWARD LATE AFTERNOON AT
KLSE. ATTENTION THEN TURNS TO FOG/STRATUS OVERNIGHT. SEVERAL
POSITIVES GOING FOR AN IFR PERIOD OVERNIGHT INCLUDE HIGHER
SURFACE DEWPOINTS...RECENT RAINFALL...AND EXPECTED CLEARING SKIES
LATE THIS EVENING. SURFACE WINDS LIKELY SHOULD DROP TO LESS THAN
5 KTS AFTER 06Z...THROUGH A DEPTH OF A FEW HUNDRED FEET. SOUNDINGS
SHOW LESS THAN 10 KTS THROUGH ABOUT 1000 FEET...BUT THE TREND IN
RECENT NAM/GFS/RAP RUNS SHOWS THIS COULD END UP HIGHER. IN THE
END...IF SKIES DO INDEED CLEAR OUT PARTIALLY...AND AHEAD OF HIGH
LEVEL CLOUDS BY MORNING...THEN IFR FOG/STRATUS SEEMS LIKELY AND
COULD GO DOWN TO 1/4SM FOR A LONGER PERIOD. FOR NOW...BROUGHT
VISIBILITIES DOWN TO 1SM AND INCLUDED A SCATTERED IFR CEILING.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...DTJ
LONG TERM....DTJ
AVIATION.....ZT
AREA FORECAST DISCUSSION...UPDATED
NWS MILWAUKEE/SULLIVAN WI
1011 AM CDT FRI JUL 25 2014
.UPDATE...
CHANCE FOR SHOWERS AND A FEW STORMS WILL CONTINUE THROUGH THE DAY
TODAY AS WARM ADVECTION LINGERS ACROSS SOUTHERN WISCONSIN. BEST
CHANCE LOOKS TO BE FROM LATE THIS MORNING UNTIL AROUND 4 PM OR SO
GIVEN LATEST RAP AND HRRR. MIGHT HAVE TO LOWER AFTERNOON HIGHS A
BIT GIVEN EXTENSIVE CLOUD COVER ACROSS THE REGION.
&&
.AVIATION/18Z TAFS/...
CHANCE FOR SHOWERS AND A FEW STORMS WILL CONTINUE THROUGH THE DAY
TODAY AS WARM ADVECTION LINGERS ACROSS SOUTHERN WISCONSIN. BEST
CHANCE LOOKS TO BE FROM LATE THIS MORNING UNTIL AROUND 4 PM OR SO
GIVEN LATEST RAP AND HRRR. THE CHANCE FOR SHOWERS/STORMS WILL
PERSIST INTO TONIGHT AS THE TROUGH AXIS AND SFC FRONT APPROACH.
VFR CONDITIONS WILL GENERALLY PERSIST THROUGH SATURDAY...THROUGH
UPSTREAM OBS AND MODEL SOUNDINGS SHOW THE POTENTIAL FOR SOME MVFR
CIGS AT TIMES.
&&
.PREV DISCUSSION... /ISSUED 558 AM CDT FRI JUL 25 2014/
UPDATE...
CHANGED WORDING IN FORECAST TO ISOLATED/SCATTERED AS OBS UNDER UPSTREAM
RETURNS APPROACHING PORTIONS OF EAST CENTRAL WI ARE REPORTING
SPRINKLES/LIGHT RAIN SHOWERS WITH TRACE AMOUNTS. A FEW GROUND
STROKES WEST OF MADISON SO ISOLATED/SCT THUNDERSTORMS THERE.
ALSO EXPANDED POPS FOR LATER THIS MORNING AS LINE OF CONVECTION
MOVING INTO WEST CENTRAL WI TRACKING MORE WITH THE 850-300 MB MEAN
WIND ALMOST DUE EAST VERSUS THE ANTICIPATED SOUTH-SOUTHEAST PER
CORFIDI VECTORS.
PREV DISCUSSION... /ISSUED 345 AM CDT FRI JUL 25 2014/
TODAY AND TONIGHT...FORECAST CONFIDENCE IS MEDIUM.
POCKETS OF CONVECTION EXTENDING FROM NORTHEAST SOUTH DAKOTA AND
SW MN INTO ERN NEBRASKA DEVELOPING ALONG LEADING EDGE OF SFC TO
850 MB MOISTURE PLUME IN REGION OF DEEP MOISTURE CONVERGENCE AND
THETA-E ADVECTION AHEAD OF 850 MB LOW/SFC LOW WITH MOST UNSTABLE
CAPE OF 1000 J/KG OR HIGHER.
THESE POCKETS OF CONVECTION ARE SETTING UP TO THE SW AND WEST OF
STRONG 850 MB FRONTOGENETIC RESPONSE TO THE LOW LEVEL JET
IMPINGING ON 850 MB BAROCLINIC ZONE STRETCHING ACROSS W CENTRAL TO
SOUTH CENTRAL MN INTO NE IOWA.
HI RES/RAPID UPDATE MODELS CATCHING ON TO LACK OF MOISTURE AND
INSTABILITY OVER WI AND KEEPING PCPN OUT OF CWA UNTIL AFTER
12Z...WITH A FEW ACCAS SPRINKLES POSSIBLE BEFORE THEN.
MODELS AGREE THAT AREAL COVERAGE AND AMOUNT OF PRECIPITATION WILL
DIMINISH AS WEAKENING FORCING AND OMEGA PUSHES ACROSS STATE WITH
DIURNALLY WEAKENING LLJ THIS MORNING/EARLY AFTERNOON. WILL KEEP
POPS IN CHANCE/SCATTERED CATEGORY AND MAINLY SHOWERS WITH ONLY A
SLGT CHANCE OF THUNDER DUE TO CAPPING AND MARGINAL MID LEVEL
LAPSE RATES.
LOOKING FOR A BREAK IN THE PCPN MID AFTERNOON...THEN REDEVELOPING
AS LOW LEVEL JET BEGINS TO STRENGTHEN LATE THIS AFTERNOON AND
EVENING. CAP AT 700 MB ERODES EARLY TO MID EVENING...BUT STILL
SOME QUESTION TO AMOUNT OF SURFACE BASED CAPE. HOWEVER DECENT
ELEVATED CAPE FOR THUNDERSTORMS. 0 TO 6KM SHEAR SUFFICIENT FOR
SUSTAINED UPDRAFTS...AND WITH STEEPENING MID-LEVEL LAPSE
RATES...SOME HAIL NOT OUT OF THE QUESTION THOUGH PROBABILITY FOR
SEVERE HAIL IS LOW. PW/S REACH NEAR 2 INCHES BY 06Z SO HEAVY
DOWNPOURS POSSIBLE... ESPECIALLY IN THE FAR SOUTH AND SOUTHEAST.
SHORT TERM...SATURDAY THROUGH SUNDAY NIGHT...FORECAST CONFIDENCE
IS MEDIUM.
MODELS SHOWING QPF ASSOCIATED WITH MAIN PUSH OF WARM AIR ADVECTION
MOVING OFF TO THE EAST ON SATURDAY. AREA FORECAST SOUNDINGS
SHOWING CAPPED AIRMASS OVER SOUTHERN WISCONSIN...WITH NOT MUCH
FORCING FOR UPWARD VERTICAL MOTION SEEN. THUS...KEPT SATURDAY DRY
ACROSS THE AREA. WARM AND HUMID CONDITIONS WILL PREVAIL...WITH
HIGHS REACHING THE MID 80S IN MOST AREAS PER 925 MB TEMPERATURE
FIELDS.
KEPT LOW POPS IN THE WESTERN COUNTIES SATURDAY NIGHT...WITH
APPROACH OF 500 MB SHORTWAVE TROUGH. HOWEVER...THIS WILL STILL
HAVE TO CONTEND WITH FAIRLY STRONG CAP OVER THE AREA. SO...MOST OF
THE NIGHT MAY REMAIN DRY IN THIS AREA.
MODELS THEN BRING COLD FRONT SOUTHEASTWARD THROUGH THE AREA SUNDAY
MORNING INTO EARLY AFTERNOON...WITH TRAILING 500 MB SHORTWAVE
TROUGH MOVING THROUGH DURING THE AFTERNOON AND EARLY EVENING. AREA
FORECAST SOUNDINGS DO MIX OUT CAP DURING THE DAY...THOUGH IT MAY
BE AFTER THE FRONTAL PASSAGE IN NORTHERN PORTIONS OF THE AREA.
KEPT LIKELY POPS FOR THUNDERSTORMS MOST OF SUNDAY...THOUGH BEST
CHANCES WILL BE IN THE MORNING BEFORE FRONTAL PASSAGE. SOME
QUESTION AS TO HOW MUCH MEAN LAYER CAPE WILL EXIST BEFORE FRONT
MOVES THROUGH. THIS WILL DETERMINE IF THERE WILL BE A HAIL
RISK...GIVEN THE STRONG DEEP LAYER SHEAR.
COLD AIR ADVECTION SUNDAY NIGHT SHOULD BRING IN COOLER AND LESS
HUMID AIR...AND END THE POPS DURING THE EVENING HOURS.
LONG TERM...MONDAY THROUGH THURSDAY...FORECAST CONFIDENCE IS
MEDIUM.
GFS/ECMWF SHOWING HIGH PRESSURE SLIDE SOUTHEAST FROM THE NORTHERN
PLAINS INTO THE MIDDLE MISSISSIPPI RIVER VALLEY REGION MONDAY INTO
WEDNESDAY. 500 MB TROUGH REMAINS ANCHORED OVER THE NORTHEAST AND
MIDDLE ATLANTIC STATES...WITH NORTH NORTHWEST FLOW OVER THE
WESTERN GREAT LAKES REGION.
VARIOUS 500 MB VORTICITY MAXIMA MOVE THROUGH THE AREA DURING THIS
TIME. ENOUGH MOISTURE LINGERS TO CARRY LOWER END POPS FOR MOST OF
THIS PERIOD. CONTINUED POPS THROUGH THURSDAY USING CONSENSUS
POPS...AS OVERALL PATTERN LINGERS. TEMPERATURES SHOULD BE PLEASANT
FOR THIS TIME OF YEAR.
AVIATION/12Z TAFS/...
AGAIN WATCHING CURRENT ACCAS SHOWER/THUNDERSTORM DEVELOPMENT FOR
ADJUSTMENTS TO TIMING INTO TAF SITES. STILL LOOKS LIKE KMSN AND
POINTS WEST HAVE THE BEST CHANCE TO SEE ISOLATED TO SCATTERED THUNDERSTORMS
WITH VERY BRIEF MVFR VSBYS THIS MORNING...WITH ONLY AN ISOLATED
LIGHT VFR SHOWER/SPRINKLES AT EASTERN TAF SITES. BETTER CHANCE
FOR THUNDER COMES LATE THIS AFTERNOON/EVENING TO ALL SITES. WILL
TRY TO HONE IN ON MOST LIKELY TIMES AT EACH SITE...BUT EVEN VARIED
SHORT-TERM MODEL DIFFERENCES HANDLING CURRENT PCPN...AS WELL AS
TIMING/AMOUNTS LATER TODAY AND TONIGHT. WILL CARRY PREVAILING VFR
WITH MVFR CIGS/VSBYS WITH THUNDER.
MARINE...
SOUTH TO SOUTHWEST WINDS REMAIN LOW ENOUGH TO NOT CAUSE ANY
WIND/WAVE ISSUES INTO SUNDAY EVENING. LOOKING AT THUNDERSTORM
CHANCES INCREASING LATE THIS AFTERNOON INTO TONIGHT...AND AGAIN ON
SUNDAY.
NORTH WINDS TO INCREASE SUNDAY NIGHT INTO MONDAY BRINGING
WINDS/WAVES TOWARD SMALL CRAFT ADVISORY LEVELS...AS WELL AS A
BEACH HAZARD POTENTIAL ON MONDAY.
&&
.MKX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
LM...NONE.
&&
$$
UPDATE...DDV
TODAY/TONIGHT AND AVIATION/MARINE...REM
SATURDAY THROUGH THURSDAY...WOOD
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
651 AM CDT FRI JUL 25 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 303 AM CDT FRI JUL 25 2014
LATEST MOSAIC RADAR SHOWING A LINE OF SHOWERS AND THUNDERSTORMS
DEVELOPING FROM WEST CENTRAL MINNESOTA INTO CENTRAL IOWA EARLY
THIS MORNING. THE SHOWERS AND THUNDERSTORMS IS ON THE NOSE OF THE
LOW LEVEL JET/MOISTURE TRANSPORT AND CONVERGENCE IN THE 925-850MB
LAYER PER THE LATEST 25.03 RAP AND 25.00Z GFS/NAM.
THE 25.00Z NAM/GFS AND THE 25.03Z RAP INDICATE THE NOSE OF LOW LEVEL
JET/MOISTURE TRANSPORT AND CONVERGENCE WILL BE POINTED DIRECTLY INTO
MAINLY THE SOUTHERN FORECAST AREA THROUGH 18Z TODAY. HOWEVER...THE
MODELS SHOW THE CORFIDI VECTORS/UPWIND PROPAGATION VECTORS TO MOVE
THE SHOWERS AND THUNDERSTORMS SOUTH TO SOUTHEAST AND IMPACT MAINLY
THE SOUTHERN FORECAST AREA TODAY. THIS IS EVIDENT WITH MOVEMENT OF
THE THUNDERSTORMS EARLY THIS MORNING PER THE LATEST MOSAIC RADAR.
AT THIS TIME...SEVERE WEATHER THREAT LOOKS TO BE MINIMAL WITH THE
THUNDERSTORMS...AS THE LATEST 25.00Z NAM AND 25.03Z RAP SHOW 0-6KM
MOST UNSTABLE CAPE LESS THAN 1000 J/KG AND THE BETTER ELEVATED
INSTABILITY TO BE WEST OF THE DEVELOPING THUNDERSTORM
ACTIVITY/NOSE OF THE LOW LEVEL JET/MOISTURE CONVERGENCE. THE
MODELS SHOW PRECIPITABLE WATERS APPROACHING 1.5 TO 2 INCHES LATE
THIS MORNING. SOME OF THE THUNDERSTORMS COULD PRODUCE LOCAL HEAVY
RAINFALL.
THE LOW LEVEL JET/MOISTURE CONVERGENCE WEAKENS AND MOVES EAST OF
THE FORECAST AREA THIS AFTERNOON AND EVENING AND WILL ALLOW FOR
SKIES AND PRECIPITATION CHANCES TO DIMINISH WEST TO EAST ACROSS
THE FORECAST AREA.
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 303 AM CDT FRI JUL 25 2014
NEXT CONCERN IS CLOSED UPPER LEVEL LOW OVER SOUTHERN SASKATCHEWAN
AND ALBERTA SLOWLY MEANDERS OVER THE UPPER GREAT LAKES REGION
SATURDAY NIGHT INTO SUNDAY. THE 25.00Z GFS/NAM SHOW MUCH STRONGER
AND DEEPER QG FORCING IN ASSOCIATION WITH THE UPPER LEVEL LOW. BEST
FORCING INCREASES OVER THE NORTHERN PORTIONS OF FORECAST AREA LATE
SATURDAY NIGHT INTO SUNDAY...HENCE THE BETTER PRECIPITATION CHANCES.
THE NAM/GFS BUFKIT SOUNDINGS INDICATE WEAK ELEVATED CAPE MAINLY
ABOVE 800MB BY 18Z SUNDAY AND 0-6KM MOST UNSTABLE CAPE OF 500-1000
J/KG EAST OF THE MISSISSIPPI RIVER. WILL CONTINUE TO MENTION
ISOLATED THUNDERSTORMS SATURDAY NIGHT INTO SUNDAY.
SUNDAY NIGHT THROUGH THURSDAY...NORTHERLY FLOW DEVELOPS OVER THE
UPPER GREAT LAKES REGION PER LATEST 25.00Z GFS/ECMWF/GEM. MAIN
CONCERN IS TIMING OF THE WEAK SHORTWAVE TROUGHS EMBEDDED IN THE
NORTHERLY FLOW ALOFT AND PRODUCE SMALL PRECIPITATION CHANCES ACROSS
PARTS OF THE FORECAST AREA TUESDAY...WEDNESDAY NIGHT INTO
THURSDAY. TEMPERATURES MONDAY THROUGH THURSDAY WILL CONTINUE TO BE
UNSEASONABLY COOL ACROSS FORECAST AREA...AS THE 25.00Z GEFS
INDICATE 850MB TEMPERATURE ANOMALIES IN THE MINUS 0.5 TO MINUS 1.5
DEGREES CELSIUS RANGE.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SATURDAY MORNING)
ISSUED AT 650 AM CDT FRI JUL 25 2014
A SHORT WAVE TROUGH WILL PRODUCE SHOWERS AND THUNDERSTORMS AT BOTH
TAF SITES THIS MORNING. THIS PRECIPITATION MAY BRIEFLY REDUCE
VISIBILITIES AND CEILINGS TO MVFR. THE HRRR HAS BEEN HANDLING
THIS PRECIPITATION WELL EARLY THIS MORNING...SO FOLLOWED IT WHEN
MAKING THE TAFS. WITH THIS IN MIND...THE PRECIPITATION WILL END AT
KRST BY 25.14Z AND AT KLSE BY 25.15Z.
FOR TONIGHT...THE LAMP GUIDANCE IS SUGGESTING THAT FOG WILL REDUCE
VISIBILITIES TO MVFR AT KRST AFTER 26.06Z...AND LESS THAN A MILE
AT KLSE AFTER 26.08Z. I AM A BIT SKEPTICAL OF THIS SINCE THERE HAS
BEEN VERY LITTLE FOG OVER THE DAKOTAS AND WESTERN MINNESOTA EARLY
THIS MORNING...AND THE SOUNDINGS SHOW SOME MIXING BELOW 2K FEET.
AS A RESULT...JUST INTRODUCED SOME MVRF FOG AT THIS TIME.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...DTJ
LONG TERM...DTJ
AVIATION...BOYNE
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
303 AM CDT FRI JUL 25 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 303 AM CDT FRI JUL 25 2014
LATEST MOSAIC RADAR SHOWING A LINE OF SHOWERS AND THUNDERSTORMS
DEVELOPING FROM WEST CENTRAL MINNESOTA INTO CENTRAL IOWA EARLY
THIS MORNING. THE SHOWERS AND THUNDERSTORMS IS ON THE NOSE OF THE
LOW LEVEL JET/MOISTURE TRANSPORT AND CONVERGENCE IN THE 925-850MB
LAYER PER THE LATEST 25.03 RAP AND 25.00Z GFS/NAM.
THE 25.00Z NAM/GFS AND THE 25.03Z RAP INDICATE THE NOSE OF LOW LEVEL
JET/MOISTURE TRANSPORT AND CONVERGENCE WILL BE POINTED DIRECTLY INTO
MAINLY THE SOUTHERN FORECAST AREA THROUGH 18Z TODAY. HOWEVER...THE
MODELS SHOW THE CORFIDI VECTORS/UPWIND PROPAGATION VECTORS TO MOVE
THE SHOWERS AND THUNDERSTORMS SOUTH TO SOUTHEAST AND IMPACT MAINLY
THE SOUTHERN FORECAST AREA TODAY. THIS IS EVIDENT WITH MOVEMENT OF
THE THUNDERSTORMS EARLY THIS MORNING PER THE LATEST MOSAIC RADAR.
AT THIS TIME...SEVERE WEATHER THREAT LOOKS TO BE MINIMAL WITH THE
THUNDERSTORMS...AS THE LATEST 25.00Z NAM AND 25.03Z RAP SHOW 0-6KM
MOST UNSTABLE CAPE LESS THAN 1000 J/KG AND THE BETTER ELEVATED
INSTABILITY TO BE WEST OF THE DEVELOPING THUNDERSTORM
ACTIVITY/NOSE OF THE LOW LEVEL JET/MOISTURE CONVERGENCE. THE
MODELS SHOW PRECIPITABLE WATERS APPROACHING 1.5 TO 2 INCHES LATE
THIS MORNING. SOME OF THE THUNDERSTORMS COULD PRODUCE LOCAL HEAVY
RAINFALL.
THE LOW LEVEL JET/MOISTURE CONVERGENCE WEAKENS AND MOVES EAST OF
THE FORECAST AREA THIS AFTERNOON AND EVENING AND WILL ALLOW FOR
SKIES AND PRECIPITATION CHANCES TO DIMINISH WEST TO EAST ACROSS
THE FORECAST AREA.
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 303 AM CDT FRI JUL 25 2014
NEXT CONCERN IS CLOSED UPPER LEVEL LOW OVER SOUTHERN SASKATCHEWAN
AND ALBERTA SLOWLY MEANDERS OVER THE UPPER GREAT LAKES REGION
SATURDAY NIGHT INTO SUNDAY. THE 25.00Z GFS/NAM SHOW MUCH STRONGER
AND DEEPER QG FORCING IN ASSOCIATION WITH THE UPPER LEVEL LOW. BEST
FORCING INCREASES OVER THE NORTHERN PORTIONS OF FORECAST AREA LATE
SATURDAY NIGHT INTO SUNDAY...HENCE THE BETTER PRECIPITATION CHANCES.
THE NAM/GFS BUFKIT SOUNDINGS INDICATE WEAK ELEVATED CAPE MAINLY
ABOVE 800MB BY 18Z SUNDAY AND 0-6KM MOST UNSTABLE CAPE OF 500-1000
J/KG EAST OF THE MISSISSIPPI RIVER. WILL CONTINUE TO MENTION
ISOLATED THUNDERSTORMS SATURDAY NIGHT INTO SUNDAY.
SUNDAY NIGHT THROUGH THURSDAY...NORTHERLY FLOW DEVELOPS OVER THE
UPPER GREAT LAKES REGION PER LATEST 25.00Z GFS/ECMWF/GEM. MAIN
CONCERN IS TIMING OF THE WEAK SHORTWAVE TROUGHS EMBEDDED IN THE
NORTHERLY FLOW ALOFT AND PRODUCE SMALL PRECIPITATION CHANCES ACROSS
PARTS OF THE FORECAST AREA TUESDAY...WEDNESDAY NIGHT INTO
THURSDAY. TEMPERATURES MONDAY THROUGH THURSDAY WILL CONTINUE TO BE
UNSEASONABLY COOL ACROSS FORECAST AREA...AS THE 25.00Z GEFS
INDICATE 850MB TEMPERATURE ANOMALIES IN THE MINUS 0.5 TO MINUS 1.5
DEGREES CELSIUS RANGE.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z FRIDAY NIGHT)
ISSUED AT 1138 PM CDT THU JUL 24 2014
WARM AND HUMID AIR ABOVE THE GROUND IS RAPIDLY TRANSPORTING NORTH
ACROSS THE PLAINS...AND WILL SHORTLY TURN EASTWARD TOWARDS THE TAF
SITES. ANTICIPATING SHOWERS AND THUNDERSTORMS TO FORM ON THE NOSE
OF THIS AIRMASS COMING IN...MOVING INTO RST AROUND 10Z AND LSE
AROUND 11Z. THERE CONTINUES TO BE A SIGNAL FOR THE STORMS TO WANE
AS THEY APPROACH LSE...THUS ONLY A VCTS IS INCLUDED THERE...BUT DO
HAVE AN 11-13Z TEMPO GROUP FOR MVFR VISIBILITY REDUCTION IN
HEAVIER SHOWERS. AT RST...CONFIDENCE IS HIGHER FOR THUNDER WITH
MORE INSTABILITY AVAILABLE...THUS A 10-12Z TEMPO GROUP IS
INCLUDED FOR TSRA...AN IFR VISIBILITY AND MVFR CEILINGS. EXPECT
THE PRECIPITATION TO HEAD OFF TO THE EAST-SOUTHEAST DURING THE MID
MORNING HOURS...ALLOWING PRECIPITATION TO END BY 15Z AT RST AND
17Z AT LSE. VFR CONDITIONS SHOULD THEN BE THE RULE THROUGH THIS
EVENING AS WARM AIR ABOVE THE GROUND HELPS PREVENT STORMS FROM
FIRING.
IN THE WIND DEPARTMENT...A CORRIDOR OF 35-40 KT SOUTHWEST WINDS
AT 1500 FT AGL COMING ACROSS IN THE MID MORNING HOURS COULD MIX
DOWN TO THE SURFACE. THEREFORE...HAVE GUSTS AROUND 20 KT MENTIONED
IN THE TAFS. WILL HAVE TO MONITOR THE WINDS CLOSELY IN THE WAKE OF
THE SHOWERS/STORMS.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...DTJ
LONG TERM...DTJ
AVIATION...AJ
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
1138 PM CDT THU JUL 24 2014
.UPDATE...
ISSUED AT 849 PM CDT THU JUL 24 2014
HAVE DRIED OUT THE FORECAST FOR THE REST OF THE EVENING WITH
SUBSIDENCE IN THE WAKE OF THE AFTERNOON/EARLY EVENING COMPLEX IN
CONTROL. HOWEVER...SOMETHING TO MONITOR IS A SHOWER DEVELOPING
WEST OF ALEXANDRIA MN. ATTENTION OTHERWISE FOCUSES TO A CLUSTER
OF STORMS OVER NORTHWEST SOUTH DAKOTA. 24.23Z HRRR AND 25.00Z RAP
TAKE THIS CLUSTER ACROSS NORTHERN SOUTH DAKOTA...BASICALLY
CROSSING THE UPPER RIDGE AXIS THERE. AS THE COMPLEX APPROACHES
NORTHEAST SOUTH DAKOTA...A LOW LEVEL JET INCREASE IS EXPECTED
ALONG WITH VEERING TO POINT TOWARDS THE FORECAST AREA. IN
FACT...THIS INCREASE AND TURNING IS ALREADY TAKING PLACE AT FSD
WHERE SOUTH-SOUTHWEST 45 KT 850MB WINDS EXIST ON THEIR RADAR. A
BAND OF SHOWERS AND STORMS IS LIKELY TO INITIATE ON THE NOSE OF
THE LOW LEVEL JET...EVENTUALLY PROGRESSING INTO WESTERN PORTIONS
OF THE FORECAST AREA BETWEEN 09-10Z AND PERHAPS TO THE MS RIVER BY
12Z.
HAVE UPDATED PRECIPITATION CHANCES AND QPF TO REFLECT THE
AFOREMENTIONED SCENARIO. SOME HINTS IN THE HRRR THAT THE STORMS
WITHIN THE SHOWERS MAY FALL APART AROUND 12Z. IF THIS TREND
CONTINUES...MAY HAVE TO PULL OR AT LEAST REDUCE THUNDER CHANCES.
UPDATE ISSUED AT 550 PM CDT THU JUL 24 2014
HAVING SOME SERIOUS CONCERNS WITH THE PRECIPITATION CHANCES THIS
EVENING...AND POSSIBLY OVERNIGHT TOO.
CURRENTLY...WATER VAPOR LOOP AND RADAR IMAGERY SHOWED A COMPLEX
OF SHOWERS AND STORMS DROPPING SOUTH...NOW INTO NORTHWEST AND
NORTH CENTRAL IOWA. THE EASTWARD PROGRESSION OF THE PRECIPITATION
TOWARDS THE FORECAST AREA HAS COME TO A HALT DUE TO THE COMPLEX
MOTION...ALONG WITH PLENTIFUL DRY AIR OVER THE FORECAST AREA.
2030Z TAMDAR SOUNDING FROM MSP SHOWED 10C OR HIGHER DEWPOINT
DEPRESSIONS FROM 770-600MB AND A DEEP INVERTED-V AT 800MB.
SUBSIDENCE IN THE WAKE OF THIS COMPLEX SHOWING UP AS A SIGNIFICANT
AREA OF CLEARING OVER WEST-CENTRAL MN...DRYING IN THE SAME
LOCATION ON WATER VAPOR...AND SURFACE PRESSURE FALLS UP TO 2
MB/HR.
ITS TOUGH FINDING A MODEL WITH A GREAT HANDLE ON THIS CURRENT
COMPLEX. THE 24.21Z RAP...24.19Z HRRR AND 24.18Z GFS SEEM TO BE
THE BEST AND ALL THREE SUGGEST THAT THE EVENING MAY NOW END UP
DRY ACROSS THE FORECAST AREA. THIS SEEMS REASONABLE AS THE
SUBSIDENCE COMES INTO THE FORECAST AREA IN THE WAKE OF THE
COMPLEX. IN FACT...GIVEN THE CLEARING UPSTREAM...ITS POSSIBLE
THAT CLEARING COMES INTO THE AREA. NEXT CONCERN THEN TURNS TO THE
OVERNIGHT CONVECTION POSSIBILITIES. WITH SUBSIDENCE AND COLD POOL
IN PLACE OVER MN AND NORTH CENTRAL IOWA...WHEN THE LOW LEVEL JET
INCREASES TONIGHT...THE CONVECTION MAY END FIRING MORE ALONG THE
WESTERN MN/IOWA BORDER. THE AFOREMENTIONED MODELS ALONG WITH THE
24.12Z ECMWF AND EVEN TO SOME DEGREE THE 24.18Z NAM ALL SHOW THAT
IDEA. IF THE CONVECTION DEVELOPS AN MCV...THEN THE CONVECTION WILL
DROP SOUTHEAST AND STAY MOSTLY WEST OF THE FORECAST AREA. THIS IS
WHAT THE 24.18Z NAM AND 24.12Z HIRES-ARW SUGGESTED. HOWEVER...IF
NO MCV FORMS...A FRONTOGENETICAL BAND OF SHOWERS AND EMBEDDED
STORMS WOULD MOVE WEST TO EAST INTO THE FORECAST AREA AFTER
07Z...PERHAPS REACHING THE MS RIVER BY 12Z.
FOR NOW...HAVE TRENDED PRECIPITATION CHANCES DOWN SOME FOR THE
EVENING AND FURTHER DECREASES ARE POSSIBLE. HAVE NOT ADJUSTED THE
OVERNIGHT YET...BUT COULD SEE A NEED TO DECREASE PRECIPITATION
CHANCES ALONG/EAST OF THE MS RIVER. NEEDLESS TO SAY THE
PRECIPITATION CHANCES FOR TONIGHT IS A FLUID SITUATION.
&&
.SHORT TERM...(THIS EVENING THROUGH FRIDAY)
ISSUED AT 320 PM CDT THU JUL 24 2014
MAIN FORECAST PROBLEM WAS THE STORMS/WEATHER MOVING IN OVERNIGHT
INTO FRIDAY MORNING.
A TALE OF TWO AIR MASSES ACROSS THE REGION THIS MORNING IN THE
OBSERVATIONAL DATA. 24.12Z RAOBS SHOWING STEEP 700-500MB LAPSE RATES
OVER THE WESTERN DAKOTAS /9C PER KM/ AND MID-LEVEL SATURATION
OCCURRING ON THE EASTERN EDGE OF THE DEEPER N-S MOIST PLUME IN
PLACE. PRECIPITABLE WATER /PWAT/ VALUES AT KBIS/KABR BOTH ARE BOTH
OVER 125 PERCENT THIS MORNING. KBIS AND KABR SOUNDINGS BOTH SHOW
SATURATION AROUND 700MB WITH 500-1000J/KG OF ELEVATED CAPE ABOVE
700MB. EAST OF THE MOIST PLUME...STABILITY REIGNS WITH 5-6C/KM
500-700MB LAPSE RATES AND BELOW NORMAL PWAT VALUES /65 PERCENT/ AT
KMPX. THIS GRADIENT AND MOISTURE TRANSPORT CONVERGENCE OVER THE
DAKOTAS/MN BORDER AT 16Z MATCHED WELL WITH THE MORNING STORMS AND
WEATHER IN THE DAKOTAS. THIS ALL ENHANCED BY A VERY VISIBLE
SHORTWAVE TROUGH SEWRD OF KBIS AND ANOTHER NORTH OF THE MT/ND/SRN
CANADA BORDER.
AS THE LARGE SCALE SHIFTS OVER NORTH AMERICA AND THE LONG WAVE
TROUGH OVER THE EAST WEAKENS...FLAT RIDGING BUILDS ACROSS THE
NORTHERN STATES /THROUGH SATURDAY/. THIS WILL PROMOTE WARMING AND
RICHER MOISTURE TO MOVE INTO THE REGION FOR A PERIOD...BEFORE
REAMPLIFICATION OF THE TROUGH OVER THE ERN CONUS OCCURS /SUNDAY/.
BEGINNING OVERNIGHT...THE DAKOTAS AIR MASS WILL ADVECT EASTWARD
AND INTO THE AREA. THIS AIRMASS IS CHARACTERIZED BY HIGHER
MOISTURE BUT ALSO VERY WARM TEMPERATURES ALOFT AS AN ELEVATED
MIXED LAYER MOVES IN. WHILE THIS HAS STEEP MID-LEVEL LAPSE
RATES...THE 700MB TEMPERATURES WARM FROM 8C TO 12-14C
FRIDAY...PROVIDING A STOUT CAPPING INVERSION TO SURFACE BASED
CONVECTION BY AFTERNOON. THIS TRANSLATES TO A 600 J/KG SBCIN. THIS
CAP BUILDING HAS VERY GOOD CONSENSUS AMOUNT THE DETERMINISTIC
MODELS...AND HAVE LOWERED RAIN CHANCES FRIDAY AFTERNOON
ACCORDINGLY.
PRIOR TO THE ELEVATED MIXED LAYER BUILDING IN FRIDAY...LOW-LEVEL
WARM ADVECTION AND MOISTURE TRANSPORT INCREASES WITH HEIGHT FALLS
AND INCREASED SOUTHERLY FLOW OVERNIGHT. THIS EVENING THERE IS SOME
SIGNAL FOR MID-LEVEL MOISTURE TRANSPORT CONVERGENCE /700MB/ TO
MOVE IN FROM THE WEST DURING THE EVENING AND LAPSE RATES WOULD SAY
SOME MID-LEVEL TOWERING CU COULD DEVELOP SOME SHOWERS
/100-300J/KG MUCAPE/. HAVE BEEN MONITORING THE CONVECTION ENTERING
WESTERN MN AND WHILE MUCAPE VALUES HAVE INCREASED A FEW HUNDRED
FROM 15-18Z...MUCH OF MN IS STILL QUITE STABLE. HOWEVER...THE
NORTHERN SIDE SEEMS TO BE TIED TO THE 700 MB TRANSPORT CONVERGENCE
AND SHORTWAVE TROUGH APPROACHING FARGO. WOULD EXPECT ECHO TO
WEAKEN AS IT MOVES TOWARD I-35...ALTHOUGH THERE IS WEAK
FORCING...THE AIR MASS IS VERY DRY. WILL HAVE TO MONITOR...BUT
TIMING LOOKS TO FIT THE EVENING INCREASE OF PRECIPITATION CHANCES.
BY MIDNIGHT...AS THE RIDGE BUILDS EAST...MOISTURE TRANSPORT AND A 40-
50KT LOW-LEVEL JET AT 850 MB FEED THE EASTERN EDGE OF THE MOISTURE
PLUME UP THE . BY 09Z...A MESOSCALE CONVECTIVE SYSTEM IS EXPECTED
TO ENTER THE WESTERN FORECAST AREA ON VERY STRONG MOISTURE
TRANSPORT CONVERGENCE AT 850 MB /50KTS DECREASING TO 15 KTS...KDSM
TO KLSE/. THIS SIGNAL IS VERY CONSISTENT AMONG THE 24.12Z MODELS
AND LATEST RAP GUIDANCE. CORFIDI VECTORS SUGGEST SOUTHEAST
MOVEMENT TO THE STRONGER CONVECTIVE ELEMENTS...AND THIS COULD POSE
SOME PROBLEMS WITH THE COMPLEX MISSING TO THE SOUTHWEST. WITH THE
MOISTURE TRANSPORT CONVERGENCE INTO THE HEART OF THE FORECAST
AREA...WOULD THINK A MISS IS PROBABLY UNLIKELY. THIS WOULD FAVOR
THE AREAS SOUTHWEST OF I-94...ESPECIALLY INTO NORTHEAST IOWA AND
LITTLE CHANGE TO THE RAIN CHANCES WERE MADE.
PRECIPITABLE WATER VALUES INCREASE RAPIDLY OVERNIGHT WITH OVER
1.75 INCHES IN THE AREA BY MORNING AND WARM CLOUD DEPTHS OF 4 KM.
THUS HEAVY RAINFALL RATES WILL OCCUR IN THE SYSTEM...BUT MANY
AREAS CAN USE THE RAINS. SOME BRIEF CITY FLOODING IS POSSIBLE.
ISOLATED HAIL AND GUSTY WINDS HAVE BEEN ADDED TO AREAS WEST OF THE
MISS RIVER IN THE HAZ WEATHER OUTLOOK DUE TO THE MAGNITUDE OF
CONVERGENCE/FORCING AND ABOUT 1500 J/KG OF MUCAPE. SPC HAS ALSO
SHIFTED THEIR DAY 1 CONVECTIVE OUTLOOK TO NEAR OUR WESTERN
FORECAST AREA EDGE...WHICH IS APPROPRIATE. CAPPING SHOULD THEN
BUILD IN AND THE SYSTEM MOVES EAST/SOUTHEAST IN THE AFTERNOON.
.LONG TERM...(FRIDAY NIGHT THROUGH THURSDAY)
ISSUED AT 320 PM CDT THU JUL 24 2014
FRIDAY NIGHT POSES AN INTERESTING PROBLEM IN SRN WISCONSIN AS THE
CAP IS STILL FULLY IN PLACE WITH NO SURFACE BASED CONVECTION
ALLOWED PER ALL GUIDANCE /600 SBCIN AND 700MB TEMPS NEAR 14C/.
YET A HANDFUL OF DETERMINISTIC MODELS CONTINUE A SIGNAL OF QPF
ACROSS SRN WISCONSIN IN THE EVENING. HAVE KEPT A SMALL RAIN CHANCE
THERE AS IT WOULD BE SOME MID-LEVEL INSTABILITY THAT WOULD HAVE TO
BE TAPPED NORTH OF THE SURFACE LOW SHIFTING THROUGH ERN IA. THE
24.12Z NAM DOES HAVE SOME 900-800MB FRONOTGENESIS WORKING WITHIN
THE CAPPED AREA...AND POSSIBLY SOME ISENTROPIC LIFT GENERATES
STABLE SHOWERS. PREFER THE 24.12Z NAM WITH RAINFALL SOUTH OF THE
FORECAST AREA...BUT HAVE KEPT A SLIGHT CHANCE OF RAIN TO COVER
THIS SITUATION FRIDAY EVENING.
A DRYING TREND THEN IN NORTHWEST FLOW AFTER MIDNIGHT...THROUGH
SATURDAY PROVIDES A VERY NICE DRY DAY. THE HIGH PRECIPITABLE WATER
AIRMASS SHOULD PUSH SOUTH TO NEAR I-80 CORRIDOR.
STRONG QG CONVERGENCE FORCING MOVES IN SUNDAY WITH THE STRONG
TROUGH MOVING THROUGH MN/WI AS THE LONG WAVE AMPLIFIES AGAIN OVER
THE EASTERN CONUS. FORCING COMES IN LATER SATURDAY NIGHT AND IS
STRONGEST SUNDAY WITH SOME INSTABILITY. HAVE INCREASED RAIN
CHANCES FOR SUNDAY. RAIN CHANCES MAY NEED TO BE PULLED FURTHER
SOUTHWEST AS WELL DEPENDING ON THE WAVE TRACK. A CLOUDY BREEZY
SHOWERY DAY FOR MOST AREAS IT SEEMS.
MONDAY THROUGH THURSDAY HAVE BELOW NORMAL TEMPERATURES AND MOSTLY
DRY WEATHER UNDER THE INFLUENCE OF THE LONGWAVE TROUGH.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z FRIDAY NIGHT)
ISSUED AT 1138 PM CDT THU JUL 24 2014
WARM AND HUMID AIR ABOVE THE GROUND IS RAPIDLY TRANSPORTING NORTH
ACROSS THE PLAINS...AND WILL SHORTLY TURN EASTWARD TOWARDS THE TAF
SITES. ANTICIPATING SHOWERS AND THUNDERSTORMS TO FORM ON THE NOSE
OF THIS AIRMASS COMING IN...MOVING INTO RST AROUND 10Z AND LSE
AROUND 11Z. THERE CONTINUES TO BE A SIGNAL FOR THE STORMS TO WANE
AS THEY APPROACH LSE...THUS ONLY A VCTS IS INCLUDED THERE...BUT DO
HAVE AN 11-13Z TEMPO GROUP FOR MVFR VISIBILITY REDUCTION IN
HEAVIER SHOWERS. AT RST...CONFIDENCE IS HIGHER FOR THUNDER WITH
MORE INSTABILITY AVAILABLE...THUS A 10-12Z TEMPO GROUP IS
INCLUDED FOR TSRA...AN IFR VISIBILITY AND MVFR CEILINGS. EXPECT
THE PRECIPITATION TO HEAD OFF TO THE EAST-SOUTHEAST DURING THE MID
MORNING HOURS...ALLOWING PRECIPITATION TO END BY 15Z AT RST AND
17Z AT LSE. VFR CONDITIONS SHOULD THEN BE THE RULE THROUGH THIS
EVENING AS WARM AIR ABOVE THE GROUND HELPS PREVENT STORMS FROM
FIRING.
IN THE WIND DEPARTMENT...A CORRIDOR OF 35-40 KT SOUTHWEST WINDS
AT 1500 FT AGL COMING ACROSS IN THE MID MORNING HOURS COULD MIX
DOWN TO THE SURFACE. THEREFORE...HAVE GUSTS AROUND 20 KT MENTIONED
IN THE TAFS. WILL HAVE TO MONITOR THE WINDS CLOSELY IN THE WAKE OF
THE SHOWERS/STORMS.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
UPDATE...AJ
SHORT TERM...BAUMGARDT
LONG TERM...BAUMGARDT
AVIATION...AJ
AREA FORECAST DISCUSSION
NWS PHOENIX AZ
905 PM MST SAT JUL 26 2014
.SYNOPSIS...
MONSOON MOISTURE WILL REMAIN ACROSS THE REGION THROUGH AT LEAST THE
EARLY PART OF THIS WEEK...WITH A CHANCE FOR AFTERNOON AND EVENING
SHOWERS AND THUNDERSTORMS EACH DAY. DAYTIME TEMPERATURES WILL STILL
HOLD ABOVE SEASONAL NORMALS...BUT ARE EXPECTED TO REMAIN BELOW THE
NEAR-RECORD READINGS WE SAW EARLIER THIS WEEK.
&&
.DISCUSSION...
AN OVERALL QUIET DAY SO FAR WITH MOST STORMS STAYING ACROSS FAR EAST
CENTRAL AND SOUTHEAST ARIZONA...BUT A LINE OF STORMS MOVING THROUGH
GILA COUNTY MAY END UP LASTING LONG ENOUGH INTO THE LOWER DESERTS TO
BRING SOME SPOTTY AREAS OF RAIN. MOISTURE IS CURRENTLY A BIT LIMITED
ACROSS SOUTH-CENTRAL ARIZONA...BUT ACROSS EAST-CENTRAL ARIZONA MID
LEVEL LAPSE RATES ARE STEEP AND MLCAPES OF UP TO 1000 J/KG ARE
PRESENT. MODEST FLOW ALOFT OF AROUND 30 KNOTS AND FAVORABLE GUSTY
WIND SOUNDING PROFILE WILL PRESENT A STRONG WIND THREAT THIS EVENING
WITH THESE WESTWARD PROGRESSING STORMS. CURRENT THINKING IS THE
STORM OUTFLOW AND INDUCED COLD POOL FROM THE GILA COUNTY STORMS
SHOULD ALLOW FOR SOME FURTHER CELL DEVELOPMENT INTO THE LOWER
DESERTS...MAINLY ACROSS THE EASTERN PORTION OF THE PHOENIX
AREA...BUT THEY SHOULD BE SHORT-LIVED AND ACTIVITY SHOULD DIMINISH
BY AROUND MIDNIGHT. LATEST HRRR MODEL REFLECTIVITY DOES SHOW SOME
STORMS MAKING THEIR WAY THROUGH THE PHOENIX METRO AREA LATE THIS
EVENING WHILE WEAKENING AT THE SAME TIME.
FURTHER TO THE SOUTH OVER SONORA MEXICO AND SOUTHEAST ARIZONA...AN
INVERTED SHORTWAVE TROUGH CAN BE SEEN ON WATER VAPOR IMAGERY. STORMS
HAVE BEEN SLOW TO DEVELOP ALONG THE NORTHER PERIPHERY OF THIS WAVE
TODAY...BUT STORMS HAVE INCREASED IN COVERAGE OVER THE PAST COUPLE
HOURS. EXPECTING THIS WAVE TO BRING A MOISTURE SURGE INTO SOUTHERN
ARIZONA TONIGHT ALONG WITH THE POSSIBILITY OF SOME OVERNIGHT SHOWERS
AND THUNDERSTORMS. SHOULD STORMS MAKE THEIR WAY NORTHWARD INTO OUR
CWA LATER TONIGHT...EXPECTING THEM TO MAINLY BE FOCUSED ACROSS
WESTERN MARICOPA COUNTY THROUGH SOUTHWEST ARIZONA.
PRECIPITABLE WATER STEADILY INCREASES TO NEAR 1.75 INCHES BY LATE
SUNDAY AFTERNOON/EVENING OVER THE LOWER DESERTS...AND PRECIPITATION
CHANCES INCREASE AS WELL. STORMS THAT FORM SUNDAY HAVE THE POTENTIAL
TO PRODUCE STRONG GUSTY OUTFLOW WINDS AND GENERATE AREAS OF BLOWING
DUST THAT CAN CREATE DRIVING AND HEALTH HAZARDS. SOME STORMS COULD
PRODUCE HEAVY RAIN AND LOCALIZED FLOODING OF ROADWAYS AND PONDING OF
WATER IN LOW LYING AREAS.
DECENT MOISTURE WILL REMAIN IN THE AREA THROUGH MONDAY WITH
CONTINUED STORM CHANCES...BUT MODELS INDICATE A DRYING WESTERLY FLOW
WILL SET UP STARTING TUESDAY. TUESDAY MAY BE A BIT OF A TRANSITION
DAY WITH STORMS MAINLY FOCUSED ACROSS HIGHER TERRAIN AREAS...BUT
CAN/T RULE OUT A FEW STORMS ACROSS THE LOWER DESERTS. LATEST
MODEL RUNS HAVE DEFINITELY BEEN TRENDING TOWARD A SOMEWHAT DRIER MID
WEEK PERIOD WITH 1000-700MB MIXING RATIOS DROPPING INTO THE 6-8
G/KG RANGE AND PWATS DROPPING TO BETWEEN 1.0 AND 1.5 INCHES. AT THIS
MOMENT...IT LOOKS LIKE ANY MONSOON ACTIVITY FOR WEDNESDAY AND
THURSDAY WILL LIKELY BE CONFINED TO FAR EASTERN ARIZONA. MODELS THEN
POINT TOWARD A BIT OF MOISTURE RESURGENCE FOR FRIDAY INTO NEXT
SATURDAY.
TEMPERATURES FOR THE PERIOD SHOULD FALL WITHIN A SMALL TEMPERATURE
RANGE OF RIGHT AROUND SEASONAL NORMALS. SOME AREAS MAY APPROACH THE
110 DEGREE MARK FOR HIGHS ON WEDNESDAY AND THURSDAY AS DRIER AIR
ALLOWS FOR A BUMP IN TEMPERATURES.
&&
.AVIATION...
SOUTH-CENTRAL ARIZONA INCLUDING KPHX...KIWA...AND KSDL...
A CLUSTER OF SHOWERS AND THUNDERSTORMS OVER THE HIGHER TERRAIN EAST
OF PHOENIX IS EXPECTED TO SLOWLY DIMINISH AS IT PROGRESSES TO THE
WEST THROUGH 06Z...BUT THERE WILL BE A SMALL CHANCE OF A SHOWER OR
STORM TO IMPACT THE PHOENIX TERMINALS BETWEEN 05-07Z. STORM OUTFLOWS
WILL LIKELY CAUSE AN EASTERLY WIND SHIFT ALSO DURING THAT TIME WITH
THE POTENTIAL FOR SOME BRIEF GUSTY EASTERLY WINDS UP TO 30 KNOTS.
CONFIDENCE IS STILL A BIT ON THE LOW SIDE HOW FAR WEST THESE STORMS
AND OUTFLOWS WILL PROGRESS OVER THE NEXT FEW HOURS. ADDITIONAL
SHOWERS AND STORMS ARE EXPECTED FOR SUNDAY WITH A MUCH BETTER
POTENTIAL TO IMPACT AREA TERMINALS.
SOUTHEAST CALIFORNIA AND SOUTHWEST ARIZONA INCLUDING KIPL AND KBLH...
QUIET CONDITIONS THROUGH MUCH OF TONIGHT...BUT THE CHANCES FOR
ISOLATED SHOWERS AND THUNDERSTORMS WILL BE ON THE INCREASE BY SUNDAY
MORNING. EVEN THOUGH THE PROBABILITY FOR STORMS IS STILL TOO LOW TO
INTRODUCE INTO TAFS...THERE WILL BE A DECENT CHANCE OF SOME ISOLATED
STORMS AND GUSTY OUTFLOW WINDS ACROSS PORTIONS OF SOUTHEAST
CALIFORNIA AND SOUTHWEST ARIZONA DURING THE DAY SUNDAY.
AVIATION DISCUSSION NOT UPDATED FOR AMENDED TAFS.
&&
.FIRE WEATHER...
TUESDAY THROUGH SATURDAY...
NEAR NORMAL TEMPERATURES AND HIGHER RELATIVE HUMIDITY LEVELS ARE
EXPECTED. MINIMUM RELATIVE HUMIDITY LEVELS WILL RANGE FROM 15 TO 25
PERCENT AND RECOVER OVERNIGHT TO 35 TO 45 PERCENT. THERE WILL BE A
DAILY THREAT OF AFTERNOON AND EVENING THUNDERSTORMS...BUT THESE WILL
BE MAINLY CONFINED TO THE HIGHER TERRAIN OF SOUTH-CENTRAL ARIZONA.
WINDS WILL BE GENERALLY LESS THAN 15 MPH...EXCEPT IN THE VICINITY OF
THUNDERSTORMS.
&&
.PSR WATCHES/WARNINGS/ADVISORIES...
AZ...NONE.
CA...NONE.
&&
$$
VISIT US ON FACEBOOK...TWITTER...AND AT WEATHER.GOV/PHOENIX
DISCUSSION...KUHLMAN
AVIATION...KUHLMAN
FIRE WEATHER...HIRSCH/MCLANE
AREA FORECAST DISCUSSION...UPDATED FOR AVIATION
NWS PEACHTREE CITY GA
135 AM EDT SUN JUL 27 2014
.SHORT TERM /TONIGHT THROUGH SUNDAY NIGHT/...
/ISSUED AT 252 PM EDT SAT JUL 26 2014/
18Z SURFACE ANALYSIS SHOWS A WEAK SURFACE TROUGH SITUATED ACROSS
SOUTH CENTRAL GA THIS AFTERNOON. WV/500MB ANALYSIS SHOWS A WEAK
SHEAR AXIS AND SHORTWAVE IN THE VICINITY OF THE OLD FRONT. A FEW
SHOWERS HAVE POPPED UP JUST OUTSIDE OF THE CWFA. THE LATEST RUNS OF
THE HRRR DO HAVE SOME CONVECTION DEVELOPING ACROSS THE SOUTHERN TIER
OF ZONES LATE THIS EVENING...SO WILL KEEP THE MENTION OF SLIGHT
CHANCE POPS IN THE FORECAST.
ANY CONVECTION ACROSS THE SOUTHERN ZONES LATE THIS AFTERNOON/EARLY
EVENING SHOULD DIMINISH QUICKLY WITH THE SETTING OF THE SUN. SKIES
ARE EXPECTED TO BE MOSTLY CLEAR WITH NEAR NORMAL LOW TEMPERATURES.
A SLIGHT CHANCE OF SHOWERS AND THUNDERSTORMS IS ONCE AGAIN POSSIBLE
SUNDAY AFTERNOON ACROSS THE SOUTHERN ZONES. DEEPER MOISTURE WILL
CONTINUE ACROSS THAT REGION...ALONG WITH THE WEAK/STATIONARY SURFACE
TROUGH. IN ADDITION...A COLD FRONT WILL BEGIN DROP SOUTH ACROSS THE
TN VALLEY. MODELS ARE PROGGING AN MCS TO DEVELOP AND MOVE NORTH OF
THE CWFA...BUT THE TAIL END OF THE SYSTEM HAS THE POTENTIAL TO CLIP
THE NORTHERN ZONES. POPS SHOULD BEGIN TO INCREASE TO AROUND 30 TO 40
PERCENT OVERNIGHT.
MODELS CONTINUE TO PROG ANY MCS TO WEAKEN AS IT APPROACHES THE CWFA
EARLY MONDAY MORNING. HOWEVER...THERE WILL BE FAIRLY DECENT SURFACE
INSTABILITY AND STEEP MID LEVEL LAPSE RATES PRESENT. MOST OF THE MID
LEVEL FORCING WILL SKATE BY TO THE NORTH. EVEN SO...DO THINK
THUNDERSTORMS...A FEW STRONG...COULD APPROACH THE NORTHERN ZONES BY
SUNRISE MONDAY. LOCALLY HEAVY RAINFALL WILL ALSO BE POSSIBLE.
NLISTEMAA
.LONG TERM /MONDAY THROUGH SATURDAY/...
/ISSUED AT 252 PM EDT SAT JUL 26 2014/
MAINLY ONLY TWEAKS TO THE LONG TERM BASED ON THE LATEST GUIDANCE.
WITH A MUCH COOLER AIRMASS BEHIND THE NEXT FRONT...SOME LOW
TEMPERATURE RECORDS WILL BE THREATENED WEDNESDAY AND THURSDAY
MORNINGS. LEANED HARD ON WPC MAX/MIN TEMPERATURES.
BDL
PREVIOUS DISCUSSION
FRONTAL SYSTEM PUSHES SOUTH OUT OF TN SUNDAY NIGHT AND INTO N GA
MONDAY MORNING. MOISTURE INCREASES ACROSS THE STATE SUNDAY AHEAD
OF THE APPROACHING FRONTAL SYSTEM. THIS FRONT IS EXPECTED TO MOVE
INTO NW GA BY 06Z-12Z MON AND PUSH SOUTH TO THE FL BORDER BY 12Z
TUE. AS THIS FRONT MOVES ACROSS GA INSTABILITIES INCREASE WITH
CAPES EXPECTED AROUND 1000 TO 3000 J/KG AND LIS RANGING FROM -3
TO -7. SHEAR VALUES DO NOT LOOK THAT IMPRESSIVE BUT THEY DO
INCREASE A BIT WITH THE FRONTAL PASSAGE. CURRENTLY SPC HAS THE DAY
2 SLIGHT RISK AREA COMING SOUTH OUT OF TN RIGHT TO OUR NORTHERN
BORDER BY 12Z MON. SPC AS GA ON DAY 3 IN JUST A SEE TEXT AREA.
WOULD NOT BE SURPRISED TO SEE THAT EXTENDED FURTHER SOUTH AS WE
GET CLOSER TO THE EVENT. ONCE THIS FRONT PASSES THROUGH...AN UPPER
LEVEL DEEP LONG WAVE TROUGH REMAINS POSITIONED OVER THE AREA
THROUGH MUCH OF NEXT WEEK...KEEPING LOWER DEW POINTS AND COOLER
TEMPERATURES IN PLACE AT LEAST THROUGH TUE/WED. MOISTURE BEGINS TO
INCREASE AGAIN BY THE END OF THE WORK WEEK ACROSS SOUTHERN PORTION
OF OUR CWA. WILL KEEP DIURNALLY DRIVEN SLIGHT TO LOW CHANCE POPS
IN ACROSS THE AREA DAYS 6 AND 7. BEGINNING TUESDAY...SHOULD SEE
BELOW AVERAGE TEMPERATURES WITH HIGHS IN THE UPPER 70S NORTH AND
LOW 80S ELSEWHERE...AND LOWS IN THE 60S.
01
&&
.CLIMATE...
RECORDS FOR 07-30
MAX TEMPERATURE MIN TEMPERATURE
STATION HIGH LOW HIGH LOW
------- ---------- ---------- ---------- ----------
KAHN 102 1999 69 1984 76 2010 60 1925
1915
KATL 98 1986 68 1984 78 1896 61 1936
1980
KCSG 102 2010 76 1984 79 2010 65 1957
1986
KMCN 103 1986 74 1984 76 2010 62 1920
2008
1958
RECORDS FOR 07-31
MAX TEMPERATURE MIN TEMPERATURE
STATION HIGH LOW HIGH LOW
------- ---------- ---------- ---------- ----------
KAHN 103 1999 71 1916 76 1931 59 1936
KATL 99 1999 62 1936 78 1915 59 1936
1986 1896
1980
KCSG 104 1986 74 1997 78 2011 66 1997
1981 2010
KMCN 105 1986 68 1936 77 1931 61 1936
&&
.AVIATION...
06Z UPDATE...
VFR CONDITIONS ARE EXPECTED THROUGH THE TAF PERIOD... DESPITE A FEW
BRIEF PATCHES OF 4-6SM BR AROUND THIS MORNING. SCT MID LEVEL CU WILL
DEVELOP BY LATE MORNING AND PERSIST THRU THE AFTERNOON. HIGH
PRESSURE INFLUENCE AND A DRIER AIR MASS WILL GREATLY HINDER ANY
CONVECTIVE THREAT TODAY. A COLD FRONT WILL APPROACH NORTH GA LATE
TONIGHT... SO COULD SEE SOME MID LEVEL CIGS SPREAD SOUTHWARD AND
OVER THE ATLANTA TAF SITES BETWEEN 09-12Z MON. LIGHT WEST WINDS THIS
MORNING WILL INCREASE TO AROUND 10-12KTS BY LATE MORNING WITH HIGHER
GUSTS THRU THE AFTERNOON. EXPECT WSW WINDS 6-8KTS TONIGHT.
//ATL CONFIDENCE...06Z UPDATE...
HIGH CONFIDENCE ALL ELEMENTS.
39
&&
.PRELIMINARY POINT TEMPS/POPS...
ATHENS 74 95 76 91 / 5 10 20 20
ATLANTA 74 93 76 87 / 5 10 20 20
BLAIRSVILLE 67 88 68 80 / 0 20 40 20
CARTERSVILLE 71 93 74 87 / 5 10 30 20
COLUMBUS 76 95 76 92 / 10 10 10 50
GAINESVILLE 73 93 74 87 / 5 10 30 20
MACON 74 95 77 93 / 10 10 10 50
ROME 71 94 74 87 / 0 20 40 20
PEACHTREE CITY 72 93 75 89 / 5 10 20 30
VIDALIA 77 95 78 94 / 10 20 10 50
&&
.FFC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...NLISTEMAA/39
LONG TERM....BDL
AVIATION...39
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
322 AM CDT SUN JUL 27 2014
.DISCUSSION...
322 AM CDT
SYNOPSIS...ONE MORE DAY OF A DIFFICULT AND MESSY PATTERN THAT WILL
RESULT IN SHOWERS AND THUNDERSTORMS ACROSS THE REGION. NO SEVERE
STORMS ARE EXPECTED. TEMPERATURES FALL THIS AFTERNOON AND REMAIN
BELOW NORMAL THROUGH THE REST OF THE WEEK. WE DRY OUT MONDAY AND
THEN HAVE LOW CHANCES OF PRECIP TUESDAY THROUGH SATURDAY.
TODAY AND TONIGHT...
AN UPPER LEVEL LOW IS OVER NORTHERN MINNESOTA WHILE A LARGER LOW IS
OVER NORTHERN QUEBEC. A SHORTWAVE TROUGH IS ALSO OVER EASTERN IOWA
WITH CONVECTION OVER CENTRAL WI. SPOTTY SHOWERS/SPRINKLES HAVE
SPROUTED OVER SOUTHEAST WI AND NOT EXPECTING MUCH ACTIVITY FROM
THOSE SPRINKLES. ADDITIONAL MORE IMPRESSIVE CONVECTION HAS FIRED
ALONG A WEAK BOUNDARY OVER CENTRAL IL. MAY SEE A FEW STORMS SOUTH OF
A PERU TO RENSSELAER LINE EARLY THIS MORNING.
FOG IS PRESENT OVER MUCH OF THE FORECAST AREA THIS MORNING AS
WELL. CLOUD COVER IS EXPANDING FROM SOUTH TO NORTH AND VSBY
INCREASES AS THE CLOUDS MOVE OVERHEAD. AS SUCH WILL HOLD OFF ON A
DENSE FOG ADVISORY FOR NOW AND SEE HOW THE CLOUD COVER SPREADS
ACROSS THE REGION.
EXPECTING ADDITIONAL CONVECTION TO FIRE AHEAD OF THE SHORTWAVE THIS
MORNING AND MOVE INTO NORTH CENTRAL IL. INSTABILITY MAY BE
LIMITED...BUT SOME THUNDER SHOULD BE REALIZED BASED ON
OBSERVATIONAL TRENDS UPSTREAM. THE SHOWERS AND STORMS WILL PUSH
EAST INTO THE AFTERNOON AS THE SHORTWAVE MOVES THROUGH. A COLD
FRONT CURRENTLY ACROSS NW WI THROUGH CENTRAL IA WILL ALSO
TRANSVERSE THE REGION AHEAD OF THE UPPER LEVEL LOW. THE LOW WILL
SWING OVER THE LAKE THIS AFTERNOON AND EXPECTING ADDITIONAL
ISOLATED TO SCATTERED STORMS WITH THIS FEATURE. TODAY WILL NOT BE
A WASH OUT HOWEVER AND THERE SHOULD BE PLENTY OF DRY HOURS.
ISOLATED SHOWERS CONTINUE INTO THE EVENING AND THEN THE BACK SIDE
OF THE UPPER LEVEL TROUGH SLIDES SOUTH THROUGH THE REGION
OVERNIGHT CLEARING OUT THE CLOUDS.
GUSTY WINDS ARE EXPECTED...AT TIMES TO 30 MPH THIS AFTERNOON.
WITH THE STRONG WINDS OVER LAKE MICHIGAN ORIENTED PARALLEL TO THE
FETCH...WAVES WILL BUILD CONSIDERABLY TONIGHT AND PERSIST INTO
MONDAY...AND A BEACH HAZARDS STATEMENT WILL GO INTO EFFECT FOR ALL
LAKE ADJACENT COUNTIES IN THE FORECAST AREA.
CLOUD COVER SHOULD STAY WITH US MOST OF THE DAY LIMITING HOW WARM WE
GET AGAIN. HIGHS WILL VARY FROM AROUND 80 NORTH TO THE MID 80S
SOUTH WHERE THERE COULD BE MORE SUNSHINE. TEMPS AND DEWPOINTS WILL
FALL THIS AFTERNOON THOUGH AS COOLER AIR MOVES IN BEHIND THE COLD
FRONT.
MONDAY...
THE UPPER LEVEL LOW WEAKENS TO AN OPEN TROUGH AND THEN MERGES WITH
THE STRONGER LOW OVER QUEBEC MONDAY NIGHT. WE STAY STUCK IN AN
UPPER LEVEL PATTERN WITH A RIDGE TO THE WEST AND TROUGH TO THE
EAST. THE SURFACE LOW MOVES OVER NEW ENGLAND MONDAY MORNING AND
HIGH PRESSURE BUILDS OVER THE PLAINS. MONDAY LOOKS DRY WITH WEAK
VORTICITY STREAMERS PASSING BY OVERHEAD. HIGHS WILL BE WELL BELOW
NORMAL IN THE LOW TO MID 70S. ONSHORE FLOW WILL KEEP THE LAKEFRONT
NEAR 70. THEN A BEAUTIFUL NIGHT FOR SLEEPING IS IN STORE WITH LOWS
IN THE MID 50S...EXCEPT FOR AROUND 60 DOWNTOWN.
TUESDAY THROUGH SATURDAY...
WE REMAIN IN THE STAGNANT UPPER LEVEL PATTERN WITH A SURFACE HIGH
OVER THE PLAINS. KEPT PERIODIC LOW CHANCES OF SHOWERS AND STORMS IN
THE EXTENDED FORECAST AS VORTICITY STREAMERS CONTINUE TO ROTATE
THROUGH THE REGION. MOISTURE IS NOT PLENTIFUL SO NOT EXPECTING MUCH
PRECIP AT THIS TIME. TEMPERATURES ALSO REMAIN BELOW NORMAL IN THE
70S WITH A FEW SITES MAYBE REACHING 80.
JEE
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 06Z...
* MVFR FOG PROBABLE EARLY THIS MORNING WITH POSSIBLE TEMPORARY IFR
FOG.
* GUSTY WEST-NORTHWEST WINDS TODAY.
* SCATTERED SHRA LATE THIS MORNING AND AFTERNOON WITH POSSIBLE TSRA.
* CHANCE FOR TEMPORARY MVFR CIGS SUNDAY NIGHT.
//DISCUSSION...UPDATED 06Z...
MOIST LOW-LEVEL AIR ASSOCIATED WITH A BROAD SURFACE TROUGH ACROSS
THE AREA EARLY THIS MORNING HAS ENABLED PATCHY TO AREAS OF FOG TO
DEVELOP AND WOULD EXPECT A SLOW EXPANSION IN THAT THROUGH
DAYBREAK. THERE ALREADY HAVE BEEN A FEW SITES IN THE REGION TO
REPORT IFR VISIBILITY SO CANNOT RULE THAT OUT AT TAF
SITES...NAMELY THE MORE FAVORED ONES SUCH AS DPA AND GYY. SOME
STRATUS ACROSS CENTRAL IL HAS UNDULATED IN COVERAGE BUT BELIEVE
MOST OF THAT WILL REMAIN SOUTH OF THE AREA WITH FOG BEING THE
PRIMARY RESTRICTION. FOG SHOULD DISSIPATE 1-2 HOURS AFTER SUNRISE
WITH THE AID OF INCREASING WESTERLY FLOW.
A STRONG UPPER LEVEL LOW OVER NORTHERN MN EARLY THIS MORNING WILL
ROTATE SOUTHEASTWARD OVER THE AREA THIS AFTERNOON. LIFT ASSOCIATED
WITH THIS WILL PASS OVER THE REGION AT A FAVORABLE TIME...LATE
MORNING AND AFTERNOON...TO SUPPORT AN UPTICK IN SHOWERS WITH
POSSIBLE ISOLATED THUNDER. HAVE INCLUDED MENTION OF THIS IN THE
TAFS...NAMELY THE CHICAGOLAND ONES AS RFD LOOKS TO BE A LITTLE
WEST OF THE BETTER FORCING. IN ADDITION...AT THE SURFACE A COLD
FRONT WILL TURN WINDS WEST-NORTHWEST AND STEEPENING LAPSE RATES
WILL SUPPORT GUSTY WINDS IN EXCESS OF 20 KT. A SECONDARY COLD
FRONT LATE TODAY WILL CONTINUE SOME GUSTINESS POSSIBLY THROUGH THE
EVENING.
//ORD AND MDW CONFIDENCE...UPDATED 06Z...
* MEDIUM IN MVFR FOG OCCURRING BETWEEN 09Z AND 13Z. LOW IN JUST
HOW FAR VISIBILITY WILL FALL.
* HIGH IN WIND DIRECTION AND MEDIUM IN WIND SPEEDS TODAY.
* MEDIUM IN SHRA AND TIMING. LOW IN ANY TSRA OCCURRING OVER THE
TAF SITES BUT PROBABLE THERE WILL BE ISOLATED IN THE REGION THIS
AFTERNOON.
* LOW IN MVFR CIGS SUNDAY NIGHT.
//OUTLOOK FOR ORD/MDW FOR 12Z MONDAY-12Z SATURDAY...UPDATED 00Z...
MONDAY...VFR. MODERATELY STRONG NORTH-NORTHEAST WINDS.
TUESDAY THROUGH FRIDAY...PREDOMINANTLY VFR THROUGH THE PERIOD.
MTF/IZZI
&&
.MARINE...
300 AM CDT
AN ACTIVE AND ATYPICAL SUMMERTIME PATTERN WILL UNFOLD ACROSS THE
LAKE THIS AFTERNOON THROUGH MONDAY NIGHT. LOW PRESSURE OVER THE
MIDDLE OF LAKE MICHIGAN BY MID TO LATE MORNING WILL MOVE EASTWARD
AND SLOWLY DEEPEN THIS AFTERNOON INTO TONIGHT. AS THIS OCCURS...COOL
AIR ADVECTION ON ITS BACKSIDE WITHIN A TIGHTENING PRESSURE
GRADIENT WILL DRIVE STRONG NORTHERLY WINDS. THESE WINDS LOOK TO
COME UP QUICKLY LATE THIS AFTERNOON AND BE MAXIMIZED THIS EVENING
INTO EARLY OVERNIGHT AND IT IS THEN WHEN OCCASIONAL GALE FORCE
GUSTS COULD OCCUR...ESPECIALLY OVER THE CENTRAL AND SOUTHERN PART
OF THE LAKE AND INTO THE INDIANA NEARSHORE. WINDS WILL BE SLOW TO
DIMINISH DURING MONDAY BUT THEN QUICKLY DROP MONDAY NIGHT. GIVEN
THE LONG FETCH THAT WILL BE REALIZED WAVES WILL BE ON THE UPPER
END OF THE SPECTRUM FOR SUMMERTIME WITH 7 TO 10 AND OCCASIONAL
HIGHER WAVES IN THE CENTRAL AND SOUTHERN PART OF THE LAKE INTO THE
INDIANA AND POSSIBLY ILLINOIS NEARSHORE AREAS. STRONG CANADIAN
HIGH PRESSURE FOR MID-SUMMER OVER THE NORTHERN PLAINS ON MONDAY
WILL EVOLVE EASTWARD OVER LAKE MICHIGAN BY MIDWEEK.
MTF
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...BEACH HAZARDS STATEMENT...ILZ014...10 PM SUNDAY TO 4 AM TUESDAY.
BEACH HAZARDS STATEMENT...ILZ006...10 PM SUNDAY TO 10 PM MONDAY.
IN...BEACH HAZARDS STATEMENT...INZ001-INZ002...6 PM SUNDAY TO 4 AM
TUESDAY.
LM...SMALL CRAFT ADVISORY...LMZ740-LMZ741...NOON SUNDAY TO 10 PM
MONDAY.
SMALL CRAFT ADVISORY...LMZ742-LMZ743...NOON SUNDAY TO 4 AM
TUESDAY.
SMALL CRAFT ADVISORY...LMZ744-LMZ745...3 PM SUNDAY TO 4 AM
TUESDAY.
&&
$$
VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
WWW.FACEBOOK.COM/US.NATIONALWEATHERSERVICE.CHICAGO.GOV
WWW.TWITTER.COM/NWSCHICAGO
WWW.YOUTUBE.COM/NWSCHICAGO
[top]
Area Forecast Discussion
National Weather Service Lincoln IL
318 AM CDT Sun Jul 27 2014
.DISCUSSION...
ISSUED 245 AM CDT Sun Jul 27 2014
Sfc map a mess in the wake of yesterday evenings convection. Broad
sfc trof/frontal boundary hung up over the region with light and
variable winds. Some patchy fog out there, with only a couple
sites dropping to a mile vis this morning. Some convection blowing
up over the area turning over some of the air and helping to block
much more of a vis drop in that area...and potentially limiting
the temp drop predawn. Even high res short term models not
handling the current conditions well, much less the next 12 hours.
Many mesoscale dynamics out there not being represented. Front
still not yet through the region...and first issue with the
forecast will be hanging on to pops, particularly in the east with
the frontal passage later mid day and this afternoon.
SHORT TERM...Today and tomorrow...
Keeping chances in for scattered showers and thunderstorms until
the front can progress through the area. Though today is expected
to get warm in front of the boundary...tomorrow is expected to see
signif cooler temps with some relatively drier air filtering in.
Precip chances drop out of the forecast for tonight and tomorrow.
But it bears mentioning that todays pops will be complicated by
small perturbations that are not being resolved well in the
models. HRRR is closest with some approximation of the line of
showers and thunder across central ILX...and some reflection of
the wave interacting with the stalled boundary out in KS. NAM also
trying to key in on it...though it dissolves rather quickly in the
HRRR, and the NAM sends it further eastward, diving sw of ILX and
interacting with the boundary later tonight well out of ILX. More
eastward progression with that disturbance may well change the
outcome of the mid day and afternoon ts chances.
LONG TERM...Tuesday through Saturday...
Cooler air immediately behind the front begins to slowly warm back
up on Tuesday by a few degrees a day. Northwesterly flow dominates
and a deep low digging in a trof over the eastern half of the
CONUS. From mid week on, chances begin to increase with afternoon
instability showers under the deepening cyclonic flow aloft, with
a more stormy afternoon summer pattern. But will be very scattered
and low in coverage. Timing with the next wave diving into the
trof aloft bringing better chances...is lacking continuity in
models. End of the week have better chances for some rainfall...
but certainty and coverage will keep the chances low and diffuse.
HJS
&&
.AVIATION...
ISSUED 1157 PM CDT Sat Jul 26 2014
Fog has developed in areas where there was rain this afternoon.
Some places have gotten as low as 1/4sm. MVFR cigs are developing
in the north and expect this to overspread PIA and BMI during the
overnight hours. The dense fog seems to have developed around SPI
and DEC, and unsure if it will get to CMI since CMI site did not
have a lot of rain. So have tried to forecast for LIFR or IFR
conditions at SPI and DEC overnight, with MVFR at PIA/BMI/CMI.
Then all sites will improve to VFR tomorrow morning with scattered
CU developing for the daytime hours. Skies should clear for
tomorrow evening. Winds will be light and variable overnight and
then become northwesterly after the cold front moves through.
There is a slight chance that some showers will develop along the
front late tonight as it encounters the juicy air. But chances are
low and confidence is low, so will not have any mention in TAFs at
this time.
Auten
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
1242 AM CDT SUN JUL 27 2014
.DISCUSSION...
736 PM CDT
OVERALL THREAT OF SEVERE WEATHER HAS DIMINISHED IN THE NEAR TERM
AND FOR THE REMAINDER OF THE EVENING...WITH CHANCES APPEARING LOW
FOR ADDITIONAL THUNDERSTORM DEVELOPMENT OVERNIGHT.
LATEST RADAR IMAGERY DEPICTING REMAINING SHOWERY ACTIVITY EXITING
THE SOUTHEAST CWA AS COMPLEX OVER CENTRAL ILLINOIS AND INDIANA
CONTINUES TO PROGRESS TO THE EAST...LEAVING THE CWA AND MUCH OF
THE REGION TO THE NORTH AND NORTHWEST DRY AT THIS TIME. LACK OF
ANY REAL GOOD FOCUS THIS EVENING AND A STRONG CAP STILL IN PLACE
OVER LINGERING STATIONARY BOUNDARY WILL LIMIT FURTHER
STRONG/SEVERE THUNDERSTORM DEVELOPMENT FOR THE REST OF THE
EVENING. DID ADJUST POPS TO KEEP LOW CHANCE/SLIGHT CHANCE POPS FOR
SHOWERS AND THUNDERSTORMS MAINLY FOR THE SOUTHERN CWA WITH THIS
LINGERING BOUNDARY STILL IN PLACE...BUT WITH ANY FURTHER
DEVELOPMENT MORE THAN LIKELY REMAINING MORE SHOWERY. ALSO GOING TO
ADD A SLIGHT CHANCE FOR SHOWERS AND THUNDERSTORMS ACROSS THE
NORTHERN CWA VERY LATE TONIGHT INTO EARLY SUNDAY MORNING. LARGE
VORT MAX ENTERING THE FAR NORTHERN PLAINS WILL SINK SOUTHEAST
THROUGH THE UPPER MIDWEST THROUGH SUNDAY MORNING. VORT LOBE OUT
AHEAD OF IT WILL SWING SOUTHEAST TO EASTERN IOWA AND SOUTHWEST
WISCONSIN AND COULD HELP THUNDERSTORM DEVELOPMENT IN THESE
AREAS...ESPECIALLY ALONG COLD FRONTAL BOUNDARY. CONFIDENCE OF
COVERAGE AND INTENSITY IS LOW AT THIS TIME BUT THERE IS A
POSSIBILITY FOR SOME OF THIS DEVELOPMENT TO REACH FAR NORTHERN
ILLINOIS BY VERY LATE TONIGHT AND EARLY SUNDAY MORNING. IF THIS
WERE TO OCCUR...WOULD EXPECT THAT HEAVY DOWNPOURS WOULD BE THE
MAIN THREAT.
VERY MOIST CONDITIONS IN A RELAXED SURFACE PATTERN WILL BE
CONDUCIVE FOR FOG DEVELOPMENT TONIGHT ESPECIALLY AS WINDS FURTHER
DIMINISH...AND SO HAVE ADDED MENTION OF FOG FOR THE ENTIRE CWA
TONIGHT.
RODRIGUEZ
//PREV DISCUSSION...
246 PM...FORECAST CONCERN AND CHALLENGE REMAINS CONVECTIVE TRENDS
THROUGH SUNDAY MORNING.
18Z SOUNDINGS FROM ILX AND DVN THIS AFTERNOON SHOW STRONG CAPPING
IN PLACE ACROSS THE AREA. RADAR IMAGERY SHOWS LIGHT RETURNS WHICH
ARE LIKELY ELEVATED SHOWERS/WEAK CONVECTION ROOTED FROM 800MB...
ABOVE THE CAP. NOT EXPECTING MUCH ACTIVITY ACROSS NORTHERN IL WITH
THIS CAP IN PLACE BUT ISOLATED SHOWERS/SPRINKLES WILL BE POSSIBLE.
THUNDERSTORMS OVER NORTHERN MO CONTINUE MOVING EAST AND INCREASING
IN COVERAGE BUT NOT MUCH ORGANIZATION YET. AS THIS ACTIVITY MOVES
EAST INTO THE MORE CAPPED AIR...IT MAY CONTINUE TO STRUGGLE TO
ORGANIZE INTO A SEVERE LINE/COMPLEX. THUS CONFIDENCE REGARDING
CONVECTIVE TRENDS ACROSS THE SOUTHERN CWA/CENTRAL IL/CENTRAL
INDIANA ARE DECREASING AT THE MOMENT. BUT WITH THE WARM FRONTAL
BOUNDARY NEARBY AND MID 70S DEWPOINTS POOLING SOUTH OF THE
FRONT...HAVE NOT MADE ANY CHANGES TO COVERAGE/TIMING. AND WHILE
SEVERE POTENTIAL REMAINS UNCERTAIN...SHOULD STORMS BECOME SEVERE
EARLIER THOUGHTS REMAIN ON TRACK FOR WIDESPREAD DAMAGING WINDS TO
BE THE MAIN THREAT...MAINLY SOUTH OF THE KANKAKEE RIVER.
THE GRADIENT MAY BECOME WEAK ENOUGH FOR LIGHT/CALM WINDS OVERNIGHT
ESPECIALLY OVER THE SOUTHERN HALF OF THE CWA. WHILE PRECIP
COVERAGE REMAINS UNCERTAIN...LOW LEVELS WILL REMAIN QUITE MOIST
AND FOG WILL BE POSSIBLE...AND WHERE ANY RAIN DOES FALL...COULD
BECOME LOCALLY DENSE.
A COLD FRONT WILL MOVE ACROSS THE AREA SUNDAY MORNING...LIKELY
MOVING EAST OF THE CWA BY 18Z. COULD BE ISOLATED/SCATTERED
THUNDERSTORMS ALONG/AHEAD OF THIS FRONT DURING THE MID MORNING
HOURS BUT WILL BE SHORT-LIVED WITH A PERIOD OF DRY CONDITIONS
EXPECTED MIDDAY/EARLY AFTERNOON POST FRONTAL. AS COOLER AIR
SPREADS ACROSS THE AREA...DIURNAL SHOWERS AND PERHAPS A FEW
THUNDERSTORMS WILL BE POSSIBLE MID/LATE SUNDAY AFTERNOON AND THIS
WOULD BE MOST LIKELY ACROSS NORTHERN IL. AS THIS COOLER AND DRIER
AIR ADVECTS INTO THE AREA...LOW LEVEL MIXING WILL BECOME QUITE
EFFICIENT. FORECAST SOUNDINGS SHOW 25-30 KTS IN THE MIXED LAYER
BY LATE AFTERNOON...THUS WINDY CONDITIONS ARE EXPECTED SUNDAY
AFTERNOON WITH WIND GUSTS AS HIGH AS 35 MPH.
A SECONDARY COLD FRONT WILL MOVE SOUTH ACROSS THE AREA SUNDAY
NIGHT USHERING IN EVEN COOLER AIR WITH HIGHS ON MONDAY ONLY IN THE
LOWER/MID 70S. A LARGE UPPER TROUGH WILL THEN REMAIN ACROSS MUCH
OF THE GREAT LAKES REGION AND EASTERN U.S. THROUGH THE END OF NEXT
WEEK. HIGH TEMPS WILL REMAIN BELOW NORMAL...GENERALLY IN THE MID/
UPPER 70S THROUGH THE END OF NEXT WEEK. IN ADDITION THERE WILL BE
AFTERNOON/EARLY EVENING CHANCES FOR ISOLATED SHOWERS/THUNDERSTORMS
JUST ABOUT EVERYDAY. CMS
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 06Z...
* MVFR FOG PROBABLE EARLY THIS MORNING WITH POSSIBLE TEMPORARY IFR
FOG.
* GUSTY WEST-NORTHWEST WINDS TODAY.
* SCATTERED SHRA LATE THIS MORNING AND AFTERNOON WITH POSSIBLE TSRA.
* CHANCE FOR TEMPORARY MVFR CIGS SUNDAY NIGHT.
//DISCUSSION...UPDATED 06Z...
MOIST LOW-LEVEL AIR ASSOCIATED WITH A BROAD SURFACE TROUGH ACROSS
THE AREA EARLY THIS MORNING HAS ENABLED PATCHY TO AREAS OF FOG TO
DEVELOP AND WOULD EXPECT A SLOW EXPANSION IN THAT THROUGH
DAYBREAK. THERE ALREADY HAVE BEEN A FEW SITES IN THE REGION TO
REPORT IFR VISIBILITY SO CANNOT RULE THAT OUT AT TAF
SITES...NAMELY THE MORE FAVORED ONES SUCH AS DPA AND GYY. SOME
STRATUS ACROSS CENTRAL IL HAS UNDULATED IN COVERAGE BUT BELIEVE
MOST OF THAT WILL REMAIN SOUTH OF THE AREA WITH FOG BEING THE
PRIMARY RESTRICTION. FOG SHOULD DISSIPATE 1-2 HOURS AFTER SUNRISE
WITH THE AID OF INCREASING WESTERLY FLOW.
A STRONG UPPER LEVEL LOW OVER NORTHERN MN EARLY THIS MORNING WILL
ROTATE SOUTHEASTWARD OVER THE AREA THIS AFTERNOON. LIFT ASSOCIATED
WITH THIS WILL PASS OVER THE REGION AT A FAVORABLE TIME...LATE
MORNING AND AFTERNOON...TO SUPPORT AN UPTICK IN SHOWERS WITH
POSSIBLE ISOLATED THUNDER. HAVE INCLUDED MENTION OF THIS IN THE
TAFS...NAMELY THE CHICAGOLAND ONES AS RFD LOOKS TO BE A LITTLE
WEST OF THE BETTER FORCING. IN ADDITION...AT THE SURFACE A COLD
FRONT WILL TURN WINDS WEST-NORTHWEST AND STEEPENING LAPSE RATES
WILL SUPPORT GUSTY WINDS IN EXCESS OF 20 KT. A SECONDARY COLD
FRONT LATE TODAY WILL CONTINUE SOME GUSTINESS POSSIBLY THROUGH THE
EVENING.
//ORD AND MDW CONFIDENCE...UPDATED 06Z...
* MEDIUM IN MVFR FOG OCCURRING BETWEEN 09Z AND 13Z. LOW IN JUST
HOW FAR VISIBILITY WILL FALL.
* HIGH IN WIND DIRECTION AND MEDIUM IN WIND SPEEDS TODAY.
* MEDIUM IN SHRA AND TIMING. LOW IN ANY TSRA OCCURRING OVER THE
TAF SITES BUT PROBABLE THERE WILL BE ISOLATED IN THE REGION THIS
AFTERNOON.
* LOW IN MVFR CIGS SUNDAY NIGHT.
//OUTLOOK FOR ORD/MDW FOR 12Z MONDAY-12Z SATURDAY...UPDATED 00Z...
MONDAY...VFR. MODERATELY STRONG NORTH-NORTHEAST WINDS.
TUESDAY THROUGH FRIDAY...PREDOMINANTLY VFR THROUGH THE PERIOD.
MTF/IZZI
&&
.MARINE...
230 PM CDT
AN ACTIVE PERIOD OF WEATHER IS SETTING UP FOR LAKE MICHIGAN FOR
THE NEXT FEW DAYS. A DIFFUSE AREA OF LOW PRESSURE OVER THE LAKE
THIS AFTERNOON WILL KEEP WINDS RELATIVELY LIGHT AND VARIABLE...BUT
A DEEPENING LOW PRESSURE SYSTEM DROPPING THROUGH THE UPPER
MISSISSIPPI VALLEY WILL LEAD TO STRENGTHENING SOUTHERLY WINDS
OVERNIGHT TONIGHT. THE LOW IS EXPECTED TO TRACK ACROSS CENTRAL
LAKE MICHIGAN LATE TONIGHT OR EARLY SUNDAY MORNING...DRAGGING A
STRONG COLD FRONT ACROSS THE LAKE AND TURNING WINDS NORTHERLY.
WINDS SHOULD QUICKLY INCREASE TO ARND 30 KT FOLLOWING THE LOW
PASSAGE AND FROPA AND DURING THE PERIOD OF STRONGEST COLD
ADVECTION...THE SEVERAL HOURS AFTER THE PASSAGE OF THE LOW AND
COLD FRONT...OCCASIONAL GALE FORCE GUSTS WILL BE POSSIBLE. WILL
ISSUE A SMALL CRAFT ADVISORY FOR THE NEAR SHORE WATERS FOR SUNDAY
MORNING THROUGH LATE MONDAY NIGHT FOR THE ILLINOIS NEARSHORE
WATERS AND SUNDAY MORNING THROUGH EARLY TUESDAY MORNING FOR THE
INDIANA WATERS AS WINDS AND WAVES WILL BOTH EXCEED ADVISORY
CRITERIA...WITH WAVES IN THE INDIANA NEAR SHORE WATERS REACHING AS
HIGH AS 7 TO 10 FT WITH OCCASIONAL HIGHER WAVES. A NORTHWESTERLY
TO NORTHERLY FETCH OVER THE ILLINOIS WATERS WILL KEEP WAVES A BIT
LOWER...BUT SHOULD EXCEED 4-5 FT BY THE END OF THE 5NM NEARSHORE
FETCH. HIGH PRESSURE BUILDING ACROSS CENTRAL PLAINS TO THE WESTERN
GREAT LAKES BY MONDAY AFTERNOON AND EVENING SHOULD ALLOW WINDS
AND WAVES TO SUBSIDE OVER THE LAKE. AS THE HIGH SETTLES INTO THE
OHIO VALLEY TUESDAY NIGHT AND WEDNESDAY...ANOTHER LOW PRESSURE
SYSTEM DROPPING SOUTHEAST THROUGH ONTARIO DRAGGING ANOTHER COLD
FRONT DOWN THE LAKE. THIS COMBINATION SHOULD KEEP MODEST WEST TO
NORTHWEST WINDS OVER THE LAKE THROUGH MIDWEEK. ANOTHER AREA OF
SPRAWLING HIGH PRESSURE IS FORECAST TO SPREAD ACROSS THE WESTERN
GREAT LAKES REGION BY LATE IN THE WEEK...BRING BACK LIGHT AND
VARIABLE WINDS AND LOW WAVES FOR LATE IN THE WEEK AND POSSIBLY
INTO NEXT WEEKEND.
KREIN
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...BEACH HAZARDS STATEMENT...INZ001-INZ002...NOON SUNDAY TO 5 AM
TUESDAY.
LM...SMALL CRAFT ADVISORY...LMZ740-LMZ741-LMZ742...NOON SUNDAY TO 11
PM MONDAY.
SMALL CRAFT ADVISORY...LMZ743-LMZ744-LMZ745...NOON SUNDAY TO 5
AM TUESDAY.
&&
$$
VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
WWW.FACEBOOK.COM/US.NATIONALWEATHERSERVICE.CHICAGO.GOV
WWW.TWITTER.COM/NWSCHICAGO
WWW.YOUTUBE.COM/NWSCHICAGO
Area Forecast Discussion
National Weather Service Lincoln IL
1157 PM CDT Sat Jul 26 2014
.DISCUSSION...
ISSUED 901 PM CDT Sat Jul 26 2014
Already made one update to remove the watch, but will need to make
another to try to better represent expected conditions overnight.
Cold front is still northwest of the area and will be moving
through the area overnight. Some models indicate that some
additional showers and storms could develop overnight as the cold
front interacts with the moist air over the area. With lots of the
airmass worked over from the evening storms, chances may not be
that high for additional pcpn, but it remains a possibility. Fog
will also develop as skies become clear and winds become light.
Some spots already seeing fog, so will making sure this is added
in grids as well. Update will be forthcoming in a while.
Auten
&&
.AVIATION...
ISSUED 1157 PM CDT Sat Jul 26 2014
Fog has developed in areas where there was rain this afternoon.
Some places have gotten as low as 1/4sm. MVFR cigs are developing
in the north and expect this to overspread PIA and BMI during the
overnight hours. The dense fog seems to have developed around SPI
and DEC, and unsure if it will get to CMI since CMI site did not
have a lot of rain. So have tried to forecast for LIFR or IFR
conditions at SPI and DEC overnight, with MVFR at PIA/BMI/CMI.
Then all sites will improve to VFR tomorrow morning with scattered
CU developing for the daytime hours. Skies should clear for
tomorrow evening. Winds will be light and variable overnight and
then become northwesterly after the cold front moves through.
There is a slight chance that some showers will develop along the
front late tonight as it encounters the juicy air. But chances are
low and confidence is low, so will not have any mention in TAFs at
this time.
Auten
&&
.PREV DISCUSSION...
ISSUED 150 PM CDT Sat Jul 26 2014
ILX Local objective analysis as of 18z indicating the cap holding
strong across our northern forecast area where the frontal boundary
has slipped south of early this afternoon. Further south, we have
seen the cap weaken with Mixed Layer Cins down to around 100 along
the I70 corridor with Mixed Layer Capes were up to 3800 j/kg over
far west central IL where temps have climbed into the upper 80s
with dew points in the mid to upper 70s. 18z sounding from ILX and
DVN showing some moisture around 2500-3000 feet with a dry layer
from 850 to 500 mb and the cap holding strong at both locations.
SHORT TERM...Tonight through Tuesday
Storm coverage tonight the main forecast issue as all models weaken
the cap significantly this evening as the main upper level energy
starts to push into the region accompanied by cooling temperatures
aloft. HRRR and WRF-HOP ensembles were indicating the main convection
would be tracking across northern Missouri and into central to southeast
Illinois late this afternoon and evening, along the differential heating
boundary set up by the lower cloud cover. Further south, nothing but
sunshine and temps in the low to mid 90s, so quite a contrast across
central thru southeast Illinois which many times these storms tend to
propagate through. If the cap is breached there is plenty of CAPE and
Shear to interact with this evening with a fast moving QLCS still looking
more likely at least over our southern half of the forecast this evening.
Damaging winds and large hail will be the primary threats but enough
low level shear prevalent, especially near the boundary across our
northern counties, that a tornado could develop with a persistent
rotating updraft. Some of the storms could start to back-build later
this evening as the low level jet starts to back more into a southwest
to west direction increasing the threat for locally heavy rainfall.
Storms should start to edge out of our forecast area Sunday morning
as the front settles to our southeast by afternoon. Will still keep
low chance pops going, especially across the east but some fairly
decent dry air will be advecting in on a gusty west to northwest
wind during the afternoon. Cooler and much less humid air will filter
southeast into our area Monday and Tuesday as an unseasonably deep
trof settles in north of the Great Lakes.
LONG TERM...Wednesday through Saturday
The deep h5 trof will be the main weather story for much of this
period bringing rather cool temperatures for the first few days of
August, although latest guidance was not quite as cool as previous
runs as we see daytime highs edge back to or just above 80 degrees
starting on Wednesday. Rain chances remain a challenge as models
diverge with respect to timing of individual shortwaves that drop
southeast into the region bringing mainly diurnally driven shower
and thunderstorm chances, especially on Friday and Saturday.
Smith
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS GOODLAND KS
207 AM MDT SUN JUL 27 2014
.UPDATE...
ISSUED AT 905 PM MDT SAT JUL 26 2014
DUE TO ENVIRONMENT BEING MORE STABLE THAN ANTICIPATED...HAVE
LOWERED RAINFALL CHANCES OVER EAST CENTRAL COLORADO FOR THE
EVENING. HAVE NOTICED SOME STORMS ARE FINALLY ABLE TO MOVE INTO
EAST CENTRAL COLORADO AS ELEVATED CAPE HAS BEGUN TO DEVELOP AND
THE 500MB SHORT WAVE TROUGH MOVES IN. MODELS KEEP THE UPPER LEVEL
TROUGH OVER THE SOUTH/SOUTHWEST PART OF THE AREA TONIGHT WHICH IS
WHERE THE ELEVATED CAPE WILL BE. STORM MOTION WILL BE AROUND 10
MPH SO IF STORMS DEVELOP THEY WILL BE MOVING VERY SLOW TO THE
SOUTHEAST WHICH MAY LEAD TO HEAVY RAINFALL. MOVED CHANCES FOR RAIN
FURTHER SOUTH...MAINLY ALONG/SOUTH OF HWY 40 WHERE LIFT AND
INSTABILITY ARE BEST. AM STILL THINKING THE MAJORITY OF THE STORM
COVERAGE WILL BE SOUTH OF GREELEY/WICHITA COUNTIES WHERE ELEVATED
INSTABILITY IS STRONGEST.
UPDATE ISSUED AT 647 PM MDT SAT JUL 26 2014
ALLOWED HEAT ADVISORY TO EXPIRE FOR NORTON/GRAHAM COUNTIES.
AS FAR AS PRECIP. FORECAST GOES...AM HAVING MORE CONFIDENCE THE
BETTER STORM COVERAGE WILL BE JUST SOUTH OF THE AREA WHERE STORMS
ARE CURRENTLY FIRING. OVERNIGHT ELEVATED CAPE DEVELOPS OVER THE
NORTHERN HALF OF THE AREA AS THE COLD FRONT MOVES IN. LIMITING
FACTOR WILL BE THE STRENGTH OF THE WEAK SHORT WAVE TROUGH MOVING
OVER THE NORTHERN HALF OF THE AREA AT THAT TIME. WILL CONTINUE TO
ANALYZE LATEST MODEL DATA BEFORE ALTERING FORECAST.
&&
.SHORT TERM...(THIS AFTERNOON THROUGH SUNDAY)
ISSUED AT 131 PM MDT SAT JUL 26 2014
LATEST WV IMAGE AND RAP UPPER LEVEL ANALYSIS SHOW BROAD RIDGE STILL
IN PLACE FROM THE DESERT SOUTHWEST ACROSS THE SOUTHERN PLAINS AND
INTO THE SOUTHERN MISSISSIPPI VALLEY. A PLUME OF MONSOONAL MOISTURE
CONTINUES TO ROUND THE WESTERN AND NORTHERN PERIPHERY OF THIS RIDGE
INTO THE CENTRAL ROCKIES AND HIGH PLAINS. A CLOSED LOW IS CENTERED
OVER SOUTHERN MANITOBA CANADA WITH A SHORTWAVE TROUGH OUT AHEAD OF
THIS ENTERING THE NORTHERN MISSISSIPPI VALLEY. AT THE SURFACE LOW
PRESSURE IS IN PLACE OVER OUR CWA WITH SEVERAL WEAK CONVERGENT AREAS
ACROSS OUR SOUTH...AND A COLD FRONT ENTERING NORTHWEST KANSAS FROM
COLORADO AND SOUTHWEST NEBRASKA.
RAP ANALYSIS INDICATES MODERATE SB/MIXED LAYER CAPE VALUES AHEAD OF
MEAN SURFACE TROUGH AXIS ACROSS MOST OF OUR CWA. SHEER IS NOT
PARTICULARLY IMPRESSIVE...HOWEVER WITH SOUNDINGS SHOWING INVERTED V
TYPE SOUNDINGS AND DCAPE 1000 J/KG OR HIGHER MICROBURST POTENTIAL IS
THERE FOR ANY THUNDERSTORM ACTIVITY. GUIDANCE CONTINUES TO FAVOR THE
SOUTHERN PART OF OUR CWA FOR THUNDERSTORM COVERAGE...MAINLY ALONG
AND AHEAD OF COLD FRONT. WEAK FORCING ROTATING FROM THE NORTH
LATER THIS EVENING MAY ALSO SUPPORT ADDITIONAL POST FRONTAL
THUNDERSTORM DEVELOPMENT. POP ADJUSTMENTS WERE MADE TO REFLECT
THESE TRENDS THROUGH TONIGHT. SUBSIDENT AIR MASS APPEARS TO BE IN
PLACE OVER MOST OF THE CWA SUNDAY...THOUGH BY SUNDAY AFTERNOON
UPSLOPE COMBINED WITH OVERRUNNING ALONG STALLED FRONTAL ZONE IN
COLORADO MAY ALLOW FOR SHOWER/THUNDERSTORM DEVELOPMENT INTO THE SW
PART OF THE CWA IN THE AFTERNOON.
TEMPERATURES SATURDAY SHOULD BE COOLER...HOWEVER THERE IS QUITE A
BIT OF SPREAD DUE TO NAM/SREF LINGERING PRECIP MOST OF THE DAY
ACROSS MUCH OF THE CWA. I AM NOT FAVORING THIS SOLUTION AS BETTER
SUPPORT FOR SHOWER/THUNDERSTORM (AND ANY LOW CLOUD COVER) WOULD BE
FURTHER WEST AND SOUTHWEST. IF THE NAM/SREF WERE CORRECT THEN HIGHS
IN THE LOW 80S FOR WESTERN PARTS OF THE CWA. BASED ON THE FAVORED
WARMER SOLUTION WE SHOULD SEE HIGHS WARM TO NEAR NORMAL VALUES IN
THE UPPER 80S FOR A LOT OF THE CWA SUNDAY.
.LONG TERM...(MWEDNESDAY THROUGH SATURDAY)
ISSUED AT 204 AM MDT SUN JUL 27 2014
UPPER AND LOWER LEVEL FLOW WILL REMAIN QUIET FOR THE LONG TERM
PERIOD AS A DOMINANT UPPER LEVEL RIDGE WILL KEEP MAIN JET FLOW WELL
TO THE NORTH OF THE TRI STATE AREA. HOWEVER...MODEL SOUNDINGS
CONTINUE TO INDICATE AMPLE PROFILE MOISTURE ACROSS THE AREA FOR
WEDNESDAY AND THE FIRST HALF OF THURSDAY. PRECIPITABLE WATER
AMOUNTS BETWEEN 1.25 AND 1.5 INCHES WILL BE PRESENT AREA WIDE AS
LOWER LEVEL EASTERLY FLOW IS BELOW NORTHERLY FLOW ABOVE 700 MB. THE
COLDER AIR ADVECTION ABOVE 700 MB IN COMBINATION WITH MOISTURE
ADVECTION IN THE LOWER ATMOSPHERE WILL BRING WIDESPREAD CHANCES FOR
PRECIPITATION FOR WEDNESDAY INTO THURSDAY.
DRIER AIR WILL MOVE INTO THE HIGH PLAINS THURSDAY EVENING AS WINDS
BELOW 800 MB SHIFT TO THE SOUTHWEST...WHICH SHOULD END WIDESPREAD
PRECIPITATION CHANCES THROUGH FRIDAY MORNING. WARM AIR ADVECTION
AND A ZONE OF CONFLUENCE OVER THE FORECAST AREA COMBINED WITH SOME
CAPE ALOFT FRIDAY AFTERNOON COULD SPARK SOME THUNDERSTORM
DEVELOPMENT IN EASTERN COLORADO INTO FRIDAY EVENING. A SURFACE
BOUNDARY JUST TO THE SOUTH OF THE FORECAST AREA WILL BRING CHANCES
FOR SHOWERS AND THUNDERSTORMS SATURDAY FOR LOCATIONS SOUTH OF
INTERSTATE 70.
THE COOLER AIR ADVECTION IN THE MID LEVELS WILL BRING BELOW AVERAGE
TEMPERATURES TO THE REGION FOR WEDNESDAY AND THURSDAY...WITH HIGHS
RANGING FROM THE MID 70S TO THE LOWER 80S. HIGH TEMPERATURES WILL
REBOUND WITH WARM AIR RETURNING ON FRIDAY AND SATURDAY...WITH HIGHS
IN THE MID 80S. LOW TEMPERATURES THROUGH THE PERIOD WILL BE ABOUT
NORMAL IN THE LOW TO MID 60S.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT)
ISSUED AT 1119 PM MDT SAT JUL 26 2014
VFR CONDITIONS FORECAST FOR THE 6Z TAFS. LATEST GUIDANCE HAS PUSHED
THE BETTER CHANCE FOR MVFR CEILINGS FURTHER WEST OF KGLD SO THAT
WILL NO LONGER BE A CONCERN. OTHERWISE LIGHT WINDS TONIGHT WILL
BECOME BREEZY LATE MORNING THROUGH THE AFTERNOON AS A SURFACE
HIGH PRESSURE BUILDS SOUTH INTO KANSAS. WINDS WILL BECOME LIGHT
AGAIN SUNDAY EVENING. STORM COVERAGE SHOULD REMAIN WELL SOUTHWEST
OF KGLD.
&&
.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
1123 PM MDT SAT JUL 26 2014
.UPDATE...
ISSUED AT 905 PM MDT SAT JUL 26 2014
DUE TO ENVIRONMENT BEING MORE STABLE THAN ANTICIPATED...HAVE
LOWERED RAINFALL CHANCES OVER EAST CENTRAL COLORADO FOR THE
EVENING. HAVE NOTICED SOME STORMS ARE FINALLY ABLE TO MOVE INTO
EAST CENTRAL COLORADO AS ELEVATED CAPE HAS BEGUN TO DEVELOP AND
THE 500MB SHORT WAVE TROUGH MOVES IN. MODELS KEEP THE UPPER LEVEL
TROUGH OVER THE SOUTH/SOUTHWEST PART OF THE AREA TONIGHT WHICH IS
WHERE THE ELEVATED CAPE WILL BE. STORM MOTION WILL BE AROUND 10
MPH SO IF STORMS DEVELOP THEY WILL BE MOVING VERY SLOW TO THE
SOUTHEAST WHICH MAY LEAD TO HEAVY RAINFALL. MOVED CHANCES FOR RAIN
FURTHER SOUTH...MAINLY ALONG/SOUTH OF HWY 40 WHERE LIFT AND
INSTABILITY ARE BEST. AM STILL THINKING THE MAJORITY OF THE STORM
COVERAGE WILL BE SOUTH OF GREELEY/WICHITA COUNTIES WHERE ELEVATED
INSTABILITY IS STRONGEST.
UPDATE ISSUED AT 647 PM MDT SAT JUL 26 2014
ALLOWED HEAT ADVISORY TO EXPIRE FOR NORTON/GRAHAM COUNTIES.
AS FAR AS PRECIP. FORECAST GOES...AM HAVING MORE CONFIDENCE THE
BETTER STORM COVERAGE WILL BE JUST SOUTH OF THE AREA WHERE STORMS
ARE CURRENTLY FIRING. OVERNIGHT ELEVATED CAPE DEVELOPS OVER THE
NORTHERN HALF OF THE AREA AS THE COLD FRONT MOVES IN. LIMITING
FACTOR WILL BE THE STRENGTH OF THE WEAK SHORT WAVE TROUGH MOVING
OVER THE NORTHERN HALF OF THE AREA AT THAT TIME. WILL CONTINUE TO
ANALYZE LATEST MODEL DATA BEFORE ALTERING FORECAST.
&&
.SHORT TERM...(THIS AFTERNOON THROUGH SUNDAY)
ISSUED AT 131 PM MDT SAT JUL 26 2014
LATEST WV IMAGE AND RAP UPPER LEVEL ANALYSIS SHOW BROAD RIDGE STILL
IN PLACE FROM THE DESERT SOUTHWEST ACROSS THE SOUTHERN PLAINS AND
INTO THE SOUTHERN MISSISSIPPI VALLEY. A PLUME OF MONSOONAL MOISTURE
CONTINUES TO ROUND THE WESTERN AND NORTHERN PERIPHERY OF THIS RIDGE
INTO THE CENTRAL ROCKIES AND HIGH PLAINS. A CLOSED LOW IS CENTERED
OVER SOUTHERN MANITOBA CANADA WITH A SHORTWAVE TROUGH OUT AHEAD OF
THIS ENTERING THE NORTHERN MISSISSIPPI VALLEY. AT THE SURFACE LOW
PRESSURE IS IN PLACE OVER OUR CWA WITH SEVERAL WEAK CONVERGENT AREAS
ACROSS OUR SOUTH...AND A COLD FRONT ENTERING NORTHWEST KANSAS FROM
COLORADO AND SOUTHWEST NEBRASKA.
RAP ANALYSIS INDICATES MODERATE SB/MIXED LAYER CAPE VALUES AHEAD OF
MEAN SURFACE TROUGH AXIS ACROSS MOST OF OUR CWA. SHEER IS NOT
PARTICULARLY IMPRESSIVE...HOWEVER WITH SOUNDINGS SHOWING INVERTED V
TYPE SOUNDINGS AND DCAPE 1000 J/KG OR HIGHER MICROBURST POTENTIAL IS
THERE FOR ANY THUNDERSTORM ACTIVITY. GUIDANCE CONTINUES TO FAVOR THE
SOUTHERN PART OF OUR CWA FOR THUNDERSTORM COVERAGE...MAINLY ALONG
AND AHEAD OF COLD FRONT. WEAK FORCING ROTATING FROM THE NORTH
LATER THIS EVENING MAY ALSO SUPPORT ADDITIONAL POST FRONTAL
THUNDERSTORM DEVELOPMENT. POP ADJUSTMENTS WERE MADE TO REFLECT
THESE TRENDS THROUGH TONIGHT. SUBSIDENT AIR MASS APPEARS TO BE IN
PLACE OVER MOST OF THE CWA SUNDAY...THOUGH BY SUNDAY AFTERNOON
UPSLOPE COMBINED WITH OVERRUNNING ALONG STALLED FRONTAL ZONE IN
COLORADO MAY ALLOW FOR SHOWER/THUNDERSTORM DEVELOPMENT INTO THE SW
PART OF THE CWA IN THE AFTERNOON.
TEMPERATURES SATURDAY SHOULD BE COOLER...HOWEVER THERE IS QUITE A
BIT OF SPREAD DUE TO NAM/SREF LINGERING PRECIP MOST OF THE DAY
ACROSS MUCH OF THE CWA. I AM NOT FAVORING THIS SOLUTION AS BETTER
SUPPORT FOR SHOWER/THUNDERSTORM (AND ANY LOW CLOUD COVER) WOULD BE
FURTHER WEST AND SOUTHWEST. IF THE NAM/SREF WERE CORRECT THEN HIGHS
IN THE LOW 80S FOR WESTERN PARTS OF THE CWA. BASED ON THE FAVORED
WARMER SOLUTION WE SHOULD SEE HIGHS WARM TO NEAR NORMAL VALUES IN
THE UPPER 80S FOR A LOT OF THE CWA SUNDAY.
.LONG TERM...(SUNDAY NIGHT THROUGH SATURDAY)
ISSUED AT 232 PM MDT SAT JUL 26 2014
SUNDAY NIGHT THROUGH TUESDAY...FORECAST CONCERNS FOR THE PERIOD
INCLUDE COOLING TEMPERATURES AND PRECIPITATION CHANCES...MAINLY IN
THE SOUTHWESTERN PORTION OF THE CWA. NEAR TERM MODELS IN GENERAL
AGREEMENT WITH LARGE SCALE PATTERN AND ALL SUGGEST A MUCH COOLER
START TO THE WEEK THAN THE PAST WEEK.
CWA WILL FIND ITSELF ON THE NORTHEAST FRINGE OF PERSISTENT H5 RIDGE
OVER THE ROCKIES. DESPITE THE RIDGE POSITION...PERIODS OF ASCENT
ACROSS WILL PERIODICALLY DEVELOP AS NUMEROUS SMALL SCALE
DISTURBANCES AND PERSISTENT WEAK WAA REMAIN ACROSS WESTERN HALF OF
THE CWA. ALTHOUGH FORCING IS WEAK...DO NOT SEE ANY REASON WHY MID
LEVELS WILL DRY OUT DURING THE PERIOD AND WITH ELEVATED CAPE PRESENT
THROUGHOUT THINK WE WILL SEE SEVERAL PERIODS OF SHOWERS AND WEAK
THUNDERSTORMS. TRIED TO ADD SOME DIURNAL COMPONENT TO WX TIMING AS
THINK BEST CHANCES WILL BE GENERALLY IN THE OVERNIGHT HOURS AS
MODEST LOW LEVEL JET DEVELOPS TO AID IN MOISTURE ADVECTION/FORCED
ASCENT. GIVEN THE POSITION OF GREATER INSTABILITY AND OVERALL
PATTERN AM NOT EXPECTING LARGE PRECIPITATION AMOUNTS FOR THE PERIOD.
COLD FRONTAL PASSAGE COMBINED WITH PERSISTENT CLOUD COVER WILL
LIKELY LEAD TO MUCH COOLER TEMPERATURES FOR THE PERIOD...ABOUT 10 TO
20 DEGREES COOLER THAN PAST FEW DAYS.
IN THE EXTENDED(TUESDAY NIGHT-SATURDAY)...SIMILAR PATTERN TO
CONTINUE ACROSS TRI STATE AREA THROUGH THE END OF THE WEEK AS H5
RIDGE GRADUALLY AMPLIFIES IN RESPONSE TO TROUGHING DEVELOPING ACROSS
THE SOUTHEAST AND MIDWEST. GEFS AND OPERATIONAL MODELS CONTINUE TO
SUPPORT A HIGH PRECIP POTENTIAL ON TUESDAY NIGHT AND WEDNESDAY AS
MORE SIGNIFICANT SHORT WAVE TROUGH MOVES ACROSS THE AREA. MOISTURE
AND INSTABILITY SHOULD ALREADY BE IN PLACE WITH MAIN CONCERN BEING
HOW FAR NORTH/EAST PRECIP SHIELD WILL GO. STILL THINK BEST CHANCE
FOR RAIN WILL BE ACROSS SOUTHWESTERN CWA SO MADE ONLY MINOR CHANGES
HERE. OTHERWISE...COOLER TEMPERATURES AS A FEW CHANCES FOR LIGHT
PRECIPITATION ARE ANTICIPATED FOR THE PERIOD.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT)
ISSUED AT 1119 PM MDT SAT JUL 26 2014
VFR CONDITIONS FORECAST FOR THE 6Z TAFS. LATEST GUIDANCE HAS PUSHED
THE BETTER CHANCE FOR MVFR CEILINGS FURTHER WEST OF KGLD SO THAT
WILL NO LONGER BE A CONCERN. OTHERWISE LIGHT WINDS TONIGHT WILL
BECOME BREEZY LATE MORNING THROUGH THE AFTERNOON AS A SURFACE
HIGH PRESSURE BUILDS SOUTH INTO KANSAS. WINDS WILL BECOME LIGHT
AGAIN SUNDAY EVENING. STORM COVERAGE SHOULD REMAIN WELL SOUTHWEST
OF KGLD.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
UPDATE...JTL
SHORT TERM...DR
LONG TERM...JRM
AVIATION...JTL
AREA FORECAST DISCUSSION
NWS JACKSON KY
141 AM EDT SUN JUL 27 2014
.UPDATE...
ISSUED AT 1151 PM EDT SAT JUL 26 2014
THE MCS IS WEAKENING TO THE WEST OVER CENTRAL KENTUCKY. IN DISCUSSION
WITH SPC...DECIDED NOT TO EXTEND THE WATCH INTO EASTERN KENTUCKY AS
THE STORMS ARE SHOWING A WEAKENING TREND. THERE ARE TWO STORMS WE
ARE WATCHING. ONE IS THE STORM MOVING INTO CASEY COUNTY AND THE
OTHER ONE IS OVER OWEN COUNTY. EXPECT THE LINE OF SHOWERS TO MOVE
ACROSS THE EASTERN KENTUCKY DURING THE OVERNIGHT HOURS. THERE IS
STILL A REMOTE POSSIBILITY OF GETTING A STORM CAPABLE OF PRODUCING
WIND DAMAGE...BUT THEY SHOULD BE FEW AND FAR BETWEEN. THE REST OF THE
FORECAST IS ON TRACK.
UPDATE ISSUED AT 1023 PM EDT SAT JUL 26 2014
UPDATED THE FORECAST TO BETTER REFLECT THE TIMING OF THE MCS MOVING
TOWARD THE AREA. THE LAST FEW SCANS...ON THE RADAR...THE MCS
APPROACHING FROM THE WEST IS TENDING TO DIVE TO THE SOUTH. THE
STRONGEST PORTION OF THE SYSTEM MAY JUST EFFECT THE AREA OF EASTERN
KENTUCKY WEST OF I-75. THE HIGHER THETA E VALUES ARE TO THE WEST OF
THE AREA...SO THIS BEHAVIOR AND MOVEMENT OF THE SYSTEM MAKES SENSE.
THE HRRR IS INDICATING THAT THE ST ROMS WILL WEAKEN AS THEY GET TO
EASTERN KENTUCKY. THE BIG SHOW IS STILL TOMORROW AFTERNOON. THE
COMBINATION OF ALL OF THE SEVERE PARAMETERS IS SOMETHING RARELY SEEN
IN EASTERN KENTUCKY IN JULY. WE WILL HAVE ENHANCED STAFFING AT THE
WEATHER OFFICE TOMORROW IN ANTICIPATION OF THE POTENTIAL SEVERE
THUNDERSTORMS TOMORROW AFTERNOON.
&&
.SHORT TERM...(THIS EVENING THROUGH SUNDAY NIGHT)
ISSUED AT 242 PM EDT SAT JUL 26 2014
DYNAMIC SITUATION UNFOLDING OVER THE NEXT 24 TO 36 HOURS AS A DEEP
TROUGH ALOFT DIVES INTO THE OHIO VALLEY. A STRONG COLD FRONT WILL
DROP SOUTHEAST INTO THE REGION SUPPLANTING WHAT WILL BECOME A VERY
WARM AND VERY MOIST AIRMASS IN PLACE ACROSS OUR REGION. THIS
COMBINATION OF A SPRING-TIME SETUP ALOFT COMBINED WITH SUMMER-TIME
HEAT AND HUMIDITY WILL CREATE CONDITIONS FAVORABLE FOR A SIGNIFICANT
SEVERE WEATHER OUTBREAK ON SUNDAY.
MODELS CONTINUE TO INDICATE A THUNDERSTORM COMPLEX WILL ORGANIZE TO
OUR WEST THIS AFTERNOON AND EVENING. THIS APPEARS TO BE HAPPENING
OVER MISSOURI AT THIS TIME. THESE STORMS SHOULD MARCH EASTWARD INTO
THE OVERNIGHT HOURS LIKELY ENDING UP SOMEWHERE OVER SOUTHERN INDIANA
AND NORTHERN KENTUCKY BY OR SHORTLY AFTER MIDNIGHT. THIS COMPLEX
SHOULD BE WEAKENING AS IT ENTERS OUR FORECAST AREA AFTER
MIDNIGHT...BUT CANNOT RULE OUT THE THREAT FOR DAMAGING WINDS AS IT
CROSSES THE REGION. THIS THREAT WOULD BE GREATEST FROM JKL AND
POINTS TO THE NORTH.
THE GREATER SEVERE WEATHER THREAT CONTINUES TO BE THE ANTICIPATED
SECOND ROUND OF THUNDERSTORMS EXPECTED TO ERUPT OVER US OR JUST TO
OUR NORTH SUNDAY AFTERNOON. PROVIDED EARLY MORNING CONVECTION GETS
OUT OF THE WAY IN TIME AND ATMOSPHERE DESTABILIZES AS PROJECTED...
THESE STORMS COULD BE QUITE STRONG. SOUNDINGS TOMORROW AFTERNOON ARE
IMPRESSIVE. STORM RELATIVE HELICITY VALUES EXCEED 300 M2/S2 COMBINED
WITH CAPE PROGGED TO EXCEED 3000 J/KG AND LCLS AROUND 3000 FT MSL.
IF THESE CONDITIONS VERIFY...A RARE JULY TORNADO OUTBREAK COULD
OCCUR. STILL...LOTS OF UNCERTAINTY WITH HOW TONIGHTS ACTIVITY WILL
PAN OUT AND HOW THIS WILL AFFECT OUR CONDITIONS ON SUNDAY BUT WILL
CONTINUE TO PLAY UP THE SEVERE WEATHER POTENTIAL IN OUR SUITE OF
PRODUCTS.
IN ADDITION TO THE SEVERE WEATHER CONCERNS...ISOLATED FLASH FLOODING
IS A CONCERN PRIMARILY ON SUNDAY. MOISTURE POOLING IN ADVANCE OF THE
FRONT WILL PUSH SURFACE DEWPOINTS INTO THE LOW TO MID 70S AND PWATS
WILL JUMP TO 1.75 INCHES AND ABOVE. STORM MOTIONS LOOK FAST ENOUGH
TO PRECLUDE A WIDESPREAD FLASH FLOODING THREAT...BUT AGAIN THAT WILL
DEPEND LARGELY ON HOW PRIMED WE GET BY TONIGHTS CONVECTION. NO FLASH
FLOOD WATCH WILL BE ISSUED AT THIS TIME...BUT THAT MAY NEED TO BE
REVISITED SHOULD THE INITIAL ROUND OF CONVECTION SATURATE THE GROUND
TONIGHT.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 242 PM EDT SAT JUL 26 2014
AN ANOMALOUS LARGE AND DEEP UPPER TROUGH WILL PERSIST OVER THE
EASTERN CONUS THROUGH THE PERIOD. THE SURFACE COLD FRONT MARKING THE
LEADING EDGE OF THE UNSEASONABLY COOL AIR MASS UNDER THE TROUGH WILL
BE WELL TO OUR SOUTHEAST ALREADY AS THE PERIOD STARTS...BUT RESIDUAL
LOW LEVEL MOISTURE WILL STILL BE MIXING VERTICALLY INTO THE NEW AIR
MASS AS COOLING ALOFT OCCURS. THIS MAY RESULT IN A FEW SHOWERS OR
THUNDERSTORMS MONDAY AFTERNOON OR EVENING...ESPECIALLY IN OUR NE
COUNTIES WHERE COOLER MID LEVEL TEMPS ARE EXPECTED.
ON TUESDAY...DRIER SURFACE AIR AND A MID LEVEL CAP SHOULD KEEP
CONVECTIVE CURRENTS BELOW ABOUT 10K FEET. SOME LIQUID COULD STILL
TRY TO FALL OUT OF THE CLOUDS...BUT WITH LIMITED CLOUD DEPTH AND
DRIER AIR...WILL ONLY MENTION SPRINKLES IN THE FORECAST.
A COOL AND DRY AIR MASS FIRMLY IN PLACE...COUPLED WITH A CESSATION OF
COOLING ALOFT...WILL ALLOW FOR MAINLY CLEAR SKIES FROM TUESDAY NIGHT
THROUGH THURSDAY NIGHT. NEAR RECORD LOW TEMPS WILL BE A POSSIBILITY.
AS THE HIGHLY AMPLIFIED UPPER TROUGH WEAKENS AT THE END OF THE
WEEK...MODELS AGREE ON ITS AXIS RETROGRADING TO THE WEST AS A LOW
CLOSES OFF. WITH THE LOW/TROUGH AXIS SLIPPING TO OUR WEST...WE WILL
RETURN TO ITS EAST SIDE WHICH IS SYNOPTICALLY MORE FAVORABLE FOR
PRECIP. FLOW FROM THE GULF OF MEXICO WILL STILL BE CUT OFF AND LOW
LEVEL MOISTURE WILL BE SLOW TO INCREASE...SO WILL ONLY USE LOW POPS.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT)
ISSUED AT 140 AM EDT SUN JUL 27 2014
A LARGE BUT WEAKENING MCS IS MOVING ACROSS EASTERN KY...BRINGING
LIGHT RAIN AND SOME RUMBLES OF THUNDER TO THE TAF SITES OVER THE NEXT
FEW HOURS. STORMS HAVE LOST CONSIDERABLE STRENGTH...AND CIGS SEEM TO
BE MAINTAINING VFR STATUS...THOUGH SOME HEAVIER RAIN SHOWERS COULD
TEMPORARILY DROP VSBYS DOWN TO MVFR. MAIN FOCUS NOW SHIFTS TO TOMORROW.
ONGOING FORECAST SEEMED TO HIGHLIGHT THE POTENTIAL THREATS VERY
WELL...SO MADE LITTLE CHANGES AFTER 15Z ON THIS ISSUANCE. THE LATEST
MODEL DATA IS STILL POINTING AT AN EVENT THAT IS RARELY SEEN IN
EASTERN KENTUCKY IN JULY. EXPECTING MOSTLY MVFR CIGS AND VSBY FOR THE
AREA...HOWEVER SOME OF STRONGER STORMS COULD BE CAPABLE OF DROPPING
THE VSBY TO AROUND A MILE AND PRODUCE WIND GUSTS OF 40 TO 50 KTS.
THERE IS ALSO THE THREAT OF SOME LARGE DAMAGING HAIL WITH ANY
THUNDERSTORM THAT DEVELOPS...WHICH WAS INCLUDED IN THE TAFS AS WELL.
KEPT THE TEMPO GROUP IN THE TAFS TO REFLECT THE MOST LIKELY TIMES
THAT THE STORMS WILL BE IN THE AREA...HOWEVER THUNDERSTORMS ARE
POSSIBLE ANYTIME AFTER DAWN THIS MORNING. WE WILL CONTINUE TO MONITOR
THE DEVELOPING SITUATION AND MAKE UPDATES FOR THE TAF SITES AS NEEDED
ONCE STORMS BEGIN INITIATING TOMORROW.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...JJ
SHORT TERM...ABE
LONG TERM...HAL
AVIATION...JMW
AREA FORECAST DISCUSSION...UPDATED
NWS PADUCAH KY
1135 PM CDT Sat Jul 26 2014
.UPDATE...
Issued at 1135 PM CDT SAT JUL 26 2014
Updated the aviation discussion for the 06Z TAF issuance.
&&
.SHORT TERM...(Tonight through Monday night)
Issued at 255 PM CDT SAT JUL 26 2014
All evidence points to the cap (see ILX and DVN 18Z RAOBS)
holding strong across the area late this afternoon and tonight.
The lone exception may be along the I-64 corridor, where a
complex of thunderstorms may push rapidly eastward generally in
the 01Z-05Z timeframe this evening.
The HRRR is still unable to generate a larger-scale bowing system,
as seen on some of the shorter range models this morning. The 12Z NAM
and GFS soundings show some weakness at times in the mid-level
flow across our north, so the overall organization of any storms
that develop may not be as significant as previously thought.
Individual storm cells may have enough 0-3KM SRH to support
rotating updrafts and would not be surprised to see some
supercells initially, where storms can develop this evening.
Damaging winds and large hail will be possible, and a few
tornadoes can not be ruled out with any individual cells this
evening. However, figure the cap will suppress any activity that
tries to dip south of I-64, or possibly even into our northern-
most counties.
The mid-upper 70 dewpoints have descended upon the region as expected,
and heat indices have reached triple digits over much of the area.
Already issued a Special Weather Statement for the heat. It should
subside by 7 PM, and would be surprised to see values above 105,
so will not be issuing a Heat Advisory at this time.
Overnight, the models struggle to generate much, if any,
convection over our region, so will keep PoPs at 30% or less.
The cold front will move through the region Sunday, and the low
to mid 70 dewpoints and temperatures well into the 90s are
expected ahead of it over the southeast 2/3 of the area in the
afternoon. This could lead to heat indices near today`s levels,
and a righteous airmass for strong to severe thunderstorms to feed
on. Winds ahead of the front will be nearly due west, and quite
strong, pushing Lake Wind Advisory levels, especially east of the
Mississippi River. The veered winds result in only weak
convergence along the boundary, so thunderstorm coverage is
expected to be widely scattered to scattered, with better coverage
later in the day along the Tennessee border. Certainly cannot rule
out a few severe storms mainly over west Kentucky and southwest
Indiana. The consensus of guidance is that most if not all of
the convective activity will shift south of the area by early
Sunday evening.
Will have a dry forecast for the entire area overnight Sunday
through Monday Night. A deep trough over the Great Lakes and
northeast will keep the area in strong northwest flow aloft
through the period. North winds will bring much cooler and drier
air into the region through the period, as well.
.LONG TERM...(Tuesday through Saturday)
Issued at 255 PM CDT SAT JUL 26 2014
Above medium confidence in the extended.
High pressure aloft will be firmly in place over west with a
persistent upper level trough over the east. This will place in a
much drier northerly flow in the fronts wake. This will also result
in unseasonable low RH reading for most of the upcoming week. By the
end of the week the upper level trough deepens and even suggest a
cut off upper low forming the lower Tennessee Valley Friday into the
weekend. This will allow for at least daytime storm chances mainly
in the afternoon with max heating...but could not rule out some
activity into the evening hours.
Temperatures will much cooler than normal through the extended with
lower to middle 80s for the region.
&&
.AVIATION...
Issued at 1135 PM CDT SAT JUL 26 2014
A cold frontal boundary is forecast to cross all TAF sites on
Sunday but with a small capping inversion and lack of deep
moisture, it will likely be a dry frontal passage, so did not
mention anything at this time. South southwest winds AOB 10 knots
overnight will pick up out of the west at 12-14 knots gusting to
20-22 knots after 15Z, then veer around to the northwest AOB 10
knots around in the wake of the FROPA.
&&
.PAH WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
MO...NONE.
IN...NONE.
KY...NONE.
&&
$$
SHORT TERM...DRS
LONG TERM/FIRE WX...KH
AVIATION...JP
AREA FORECAST DISCUSSION...UPDATED AVIATION
NWS ST LOUIS MO
1204 AM CDT Sun Jul 27 2014
.UPDATE:
Issued at 935 PM CDT Sat Jul 26 2014
Trying to pin down convection threat for the remainder of tonight
remains somewhat of a head scratcher. However, as we dig into the
details of the 00z UA data becoming doubtful that the the storm-
free conditions we are currently experiencing will continue
throughout the entire night.
Although all of the 00z raobs in the area are indicating that the
strong cap is persisting throughout the region early this evening, water
vapor imagery indicates that strong mid level WNW flow is
beginning to dig south as trof rotates around the unseasonably
strong mid level low near nw MN, and this should drag some cooler
mid level air into northern sections of the CWA during the
predawn hours aiding in the erosion of this wedge of warm mid
level air. In addition to this cooling and dynamics with the
shortwave, low level forcing should also be increasing as cold
front works its way into the mid-Mississippi Valley. And...
while the "cooled" air from the rain associated with this
afternoon`s MCV is currently parked over the CWA, airmass west of
our area (that missed out on the rain) remains very unstable at
02z, with MLCAPES of 4000-5000 J/KG, and this air will be
advected back into our area due to weak but persistent westerly
low level flow.
So...whether the storms form upstream and advect into the area,
or form in situ near the Mississippi River as suggested by the
latest HRRR, 18z NAM, and latest RUC runs, thunderstorms will
remain in the forecast overnight. Overall, think current trends of
ramping PoPs up after 05z is very reasonable, with the greatest
PoPs over northern and central sections of the CWA, where forcing
should be the greatest. A conditional threat of severe
thunderstorm is still in the cards for the region as noted in the
SWODY1, as large scale shear will be increasing as the westerlies
dip into the mid- Mississippi Valley and interacts with the
residually unstable ams.
Truett
&&
.SHORT TERM: (Through Late Tonight)
Issued at 324 PM CDT Sat Jul 26 2014
Primary concern continues to be convective trends for this evening.
Current trends are pointing more and more toward there being less
severe weather in our CWFA than previously expected, with the
primary threat for severe storms further north/northeast in
southeast IA and central IL. A broad area of showers and stratiform
rain associated with an MCV which is spinning its way across the
state is putting the kibosh on much of the instability which was
forecast for late this afternoon/evening. A limited ribbon of very
high CAPE (MLCAPE in excess of 3500-4000 J/Kg) remains over extreme
northeast MO into southern IA and a much larger area of high CAPE
over central and southern IL. Storms are already rumbling just
north of our CWFA in southern IA and west central IL and I would
expect these areas of storms to continue to develop and strengthen.
Still cannot rule out severe storms from Kirksville to Quincy and
southeast to Litchfield and possibly Salem...but the probability
seems to be much lower than previously expected.
After the evening severe weather threat has passed, there is still
the possibility that there could be additional development
overnight. RAP and NAM both show moderate moisture convergence at
850mb ahead of the front and generate QPF in response. Have left
chance/slight chance PoPs going for most of the area through the
night. The wind shift associated with the approaching cold front
should be sliding into the northern 1/3 of our CWFA between 09-12Z
with drier low level air trying to nose in. This should effectively
cut off the chance for additional precip in those areas in the
pre-dawn hours.
Carney
.LONG TERM: (Sunday through Next Saturday)
Issued at 340 PM CDT Sat Jul 26 2014
The cold front is expected to push through early Sunday morning. A
minimal rain threat will exist during the morning near it, with a
dry afternoon on tap behind it. The cooling effects will not be
felt too much early on, with another warm day expected: max temps
still look to top 90 degrees for most areas near and south of I-70.
The big difference will be lower humidity from today, however.
After Sunday, an extended dry period is forecast as a deep longwave
upper TROF sets up over eastern North America with a stout NW flow
aloft for our region. This usually means either dry, or surprise
hit-and-run systems this time of year, but almost always means below
average temps. For now, am going with dry until Thursday, with low
PoPs thereafter as a system works its way down into our region and
stays for a bit.
TES
&&
.AVIATION: (For the 06z TAFs through 06z Sunday Night)
Issued at 1144 PM CDT Sat Jul 26 2014
Latest surface analysis continues to show slow progress with the
frontal boundaries to our north and west. Latest surface analysis
shows stationary front extending from central Wisconsin to an area
of weak low pressure west of Kansas City then southwest into
southwest Kansas. This front has moved little within the past 3
hours. Secondary frontal boundary extends from southern Minnesota
through northwest Kansas. This front has also made little progress
to the southeast. Upstairs 500 mb shortwave from over the High
Plains will slide southeast across the upper and parts of Mid-
Mississippi Valley region by 1200 - 1800 UTC time frame. Cold
front forecast east-central Missouri between 1200-1400 UTC.
Specifics for KSTL::Light and variable winds will become west-
southwesterly 5 to 8 kts after 0900 UTC. isolated showers and
thunderstorms are possible after 1000 UTC but should be ending by
1200 UTC. Expect cold front to move across STL between 1200 and
1400 UTC. Expected scattered showers to end after 1200 UTC.
Przybylinski
&&
.LSX WATCHES/WARNINGS/ADVISORIES:
MO...NONE.
IL...NONE.
&&
$$
WFO LSX
AREA FORECAST DISCUSSION
NWS ALBUQUERQUE NM
330 AM MDT SUN JUL 27 2014
.SYNOPSIS...
SHOWERS AND STORMS...SOME WITH HEAVY RAIN WHICH COULD LEAD TO
LOCALIZED FLOODING...WILL BE INCREASING TODAY AND TONIGHT AS
MOISTURE CONTINUES TO INFILTRATE THE RIDGE ALOFT. A COLD FRONT TO
PUSH INTO THE PLAINS TODAY AND TONIGHT WILL ALSO TRIGGER MORE
WIDESPREAD SHOWERS AND STORMS. THE FRONT WILL ALSO BRING GUSTY EAST
WINDS TO THE RIO GRANDE VALLEY AS IT TRACKS WESTWARD THIS AFTERNOON
AND TONIGHT. HIGH TEMPERATURES WILL COOL DOWN CLOSER TO AVERAGE OR
EVEN A FEW DEGREES BELOW FOR MUCH OF THIS WEEK. ADDITIONAL FRONTS
TUESDAY THROUGH THURSDAY WILL POTENTIALLY LEAD TO MORE WIDESPREAD
AND LOCALLY HEAVY RAINFALL FOR AT LEAST PORTIONS OF NORTHERN AND
CENTRAL NEW MEXICO.
&&
.DISCUSSION...
A WETTER PERIOD HEADED TO NEW MEXICO TODAY AND PERSISTING THROUGH
MUCH OF THE WEEK. SURFACE BOUNDARY STILL TRACKING INTO THE EAST
CENTRAL PLAINS AT THE MOMENT CONTINUES TO SPARK WHAT APPEARS TO BE
ISOLATED SHOWERS OR A SHORT LIVED STORM. THIS BOUNDARY DOESN/T
APPEAR TO BE THE FRONT JUST YET...WHICH WILL BE STARTING TO IMPACT
THE NORTHEAST THIS AFTERNOON. THEREFORE NOT LOOKING FOR ANY RECORD
HIGH TEMPERATURES TODAY IN THAT PART OF THE STATE TODAY...AND HIGHS
OVERALL ARE EXPECTED TO BEGIN TO COOL DOWN TOWARDS AVERAGE...OR EVEN
A FEW DEGREES BELOW AS CONVECTION INCREASES THIS WEEK.
DECIDED TO EXPAND THE FLASH FLOOD WATCH FARTHER SOUTH INTO THE
NORTHEAST/EAST CENTRAL PLAINS. ANTICIPATE HEAVY RAINS COULD SAG
SOUTHWARD WITH THE FRONTAL BOUNDARY. ALSO CONSIDERED ADDING THE
JEMEZ TO THE WATCH...ESPECIALLY AS THE EAST TO SOUTHEAST WINDS
DEVELOP INTO THE RIO GRANDE VALLEY LATER TODAY/TONIGHT...BUT
DECIDED TO HOLD OFF FOR NOW. IN ANY EVENT...HAVE A MENTION OF
LOCALLY HEAVY RAIN TO MANY OF THE NORTH CENTRAL/NORTHEAST ZONES FOR
THIS AFTERNOON AND TONIGHT.
THE REST OF THE WEEK LOOKS ACTIVE ESPECIALLY THE MID WEEK
PERIOD...AS THE RIDGE AXIS EXPANDS INTO THE NORTHERN ROCKIES AND AT
LEAST PART OF NEW MEXICO IS UNDER NORTHWEST FLOW ALOFT. DISTURBANCES
WILL BRUSH THE NORTH CENTRAL/NORTHEAST AND ALLOW FRONTS TO IMPACT AT
LEAST THE PLAINS...BUT ALSO PUSHING MOISTURE WESTWARD. THIS PATTERN
PERSISTS INTO NEXT WEEKEND...THEN A STRONGER TROUGH ATTEMPTS TO
BATTER DOWN THE STRONG RIDGE...OR AT LEAST SHOVE IT EASTWARD A BIT.
&&
.FIRE WEATHER...
INCREASINGLY ACTIVE PATTERN THIS WEEK WITH HIGH LIKELIHOOD OF
WIDESPREAD HEAVY T-STORM RAINS...ESPECIALLY DURING THE TUE THRU THU
PERIOD. IN FACT...THE WED-THU PERIOD COULD END UP AMONG THE MOST
ACTIVE OF THE SEASON THUS FAR. THREAT FOR BURN SCAR FLASH FLOODING
WILL BE VERY HIGH. MAX VENTILATION RATES WILL TREND DOWNWARD AND MIN
RH/S UPWARD EACH DAY...WITH FAIR IF NOT POOR VENT CONDITIONS BY THU.
A COUPLE OF IMPORTANT TRENDS TO WATCH THRU TONIGHT. FIRST...A
SURFACE FRONTAL BOUNDARY WILL SAG SOUTHWARD ACROSS NE NEW MEXICO
LATER TODAY PROVIDING A FOCUS FOR WIDESPREAD T-STORM ACTIVITY FROM
THE SANGRE DE CRISTO MOUNTAINS TO THE NE HIGHLANDS AND PLAINS.
GUSTY EASTERLY GAP WINDS TO DEVELOP LATE IN THE AFTERNOON FOR PLACES
LIKE TAOS AND SANTA FE...EXPANDING SOUTHWARD TO INCLUDE THE RIO
GRANDE VALLEY CORRIDOR. THESE GAP WINDS COMBINED WITH OUTFLOW
BOUNDARY INTERACTIONS COULD RESULT IN A DYNAMIC THUNDERSTORM SET UP
FOR VALLEY/LOWLAND LOCATIONS BY EARLY TO MID EVENING. GAP WINDS
WILL STRENGTHEN MARKEDLY TONIGHT AND PERSIST INTO MONDAY MORNING.
THE SECOND TREND WILL BE A SUBTLE EASTWARD SHIFT OF THE LARGE-SCALE
RIDGE ALOFT OR AT LEAST A MORE NW TO SE ORIENTATION OF THE RIDGE
AXIS OVER ERN NEW MEXICO. THIS WILL ALLOW DEEP-LAYERED MOISTURE
OVER SE ARIZONA AND FAR SW NEW MEXICO TO SLOWLY WORK NORTHWARD AND
HELP TO BOOST STORM COVERAGE UPWARD OVER MUCH OF THE WEST BY THIS
EVENING...AGAIN WITH OUTFLOW BOUNDARY INTERACTIONS BECOMING KEY FOR
VALLEY AND LOWLAND LOCATIONS. THE UPPER HIGH WILL REMAIN QUITE
STRONG BECOMING CENTERED BETWEEN SANTA ROSA AND TUCUMCARI...AND ONCE
EARLY MORNING SHOWER AND CLOUD ACTIVITY DISSIPATES...IT WILL ALLOW
FOR STRONG HEATING MID TO LATE MORNING WITH CONVECTION FIRING OVER
THE HIGHER TERRAIN BY MIDDAY. STEERING WINDS WILL AGAIN REMAIN VERY
WEAK AND GENERALLY FAVOR EAST-SOUTHEAST STORM MOTIONS ACROSS NC/NE
AREAS...AND TOWARD THE WEST OR NORTHWEST FOR CENTRAL/SW AREAS OR
CLOCKWISE AROUND THE HIGH CENTER.
AN EVEN MORE ACTIVE T-STORM DAY ON MONDAY...AND A FEATURE TO WATCH
WILL BE AN INVERTED TROUGH THAT WILL SLOWLY TRACK WEST...THEN TURN
NORTH ALONG THE NM/AZ LINE. THIS WAVE WILL LIKELY TURN BACK TOWARD
THE EAST AND BECOME A SIGNIFICANT PLAYER EARLY IN THE WORK
WEEK...PARTICULARLY MONDAY NIGHT INTO TUESDAY. ANOTHER BACKDOOR COLD
FRONT WILL PUSH SOUTHWARD WED-WED PM...RECHARGING MOISTURE AND
INSTABILITY FIELDS FOR MID-WEEK. T-STORM COVERAGE WILL CONT TO RAMP
UP...WITH LATE NIGHT AND EARLY MORNING ACTIVITY LIKELY. EXTENDED
RANGE FORECASTS SUPPORT A VERY ACTIVE PATTERN ESPECIALLY CENTRAL AND
WESTERN AREAS...DESPITE A WESTWARD SHIFT OF THE UPPER HIGH THAT
BECOMES CENTERED MORE OVER ARIZONA AND GREAT BASIN. WIDESPREAD
7-DAY RAINFALL TOTALS IN THE 2 TO 5 INCH RANGE ARE LIKELY WITH
LOCALLY HIGHER AMOUNTS FROM THE SANGRE DE CRISTO TO THE NORTHEAST. KJ
&&
.AVIATION...
06Z TAF CYCLE
EARLIER HIGH RESOLUTION HRRR MODEL GUIDANCE NAILED REDEVELOPMENT
OF CONVECTIVE ACTIVITY LATE THIS EVENING FROM THE RIO GRANDE VALLEY
WESTWARD ACROSS THE CONT DVD. THE BACK DOOR FRONTAL BOUNDARY RACING
SOUTHWEST THRU THE PLAINS WILL SERVE TO FOCUS EVEN MORE DEVELOPMENT
FOR THE NEXT FEW HOURS IN THIS AREA. PLACED VCSH AT MOST TAF SITES
FROM KSAF/KABQ WEST THRU 09-10Z BUT CONFIDENCE WAS NOT HIGH ENOUGH
TO PLACE ANY TEMPO GROUPS AT THIS TIME. LOOK FOR AMENDMENTS WITH TS
IF ANY PARTICULAR AREA BECOMES FAVORED. MID LEVEL CLOUD DECKS WILL
LINGER FOR MUCH OF NORTHERN/WESTERN NM THRU ABOUT 15Z BEFORE SOME
BRIEF CLEARING DEVELOPS. TOMORROW LOOKS TO BE A VERY ACTIVE DAY
ALONG AND NORTH OF I-40 WITH ABUNDANT MOISTURE AND FORCING FROM
THE LOW LEVEL FRONT IN PLACE. HAD TO GO WITH LENGTHY VCTS AROUND
KGUP...AND FROM KLVS TO KTCC. MODELS ARE GENERATING SIGNIFICANT
PRECIP AMOUNTS AFT 00Z FOR THESE AREAS.
GUYER
&&
.PRELIMINARY POINT TEMPS/POPS...
FARMINGTON...................... 96 66 90 66 / 20 30 30 40
DULCE........................... 91 53 83 53 / 30 60 50 40
CUBA............................ 89 55 84 55 / 40 70 50 40
GALLUP.......................... 90 59 86 59 / 50 40 30 40
EL MORRO........................ 86 56 81 56 / 40 50 50 40
GRANTS.......................... 89 59 83 59 / 30 40 40 40
QUEMADO......................... 87 59 81 59 / 40 40 40 40
GLENWOOD........................ 93 58 87 58 / 40 30 30 30
CHAMA........................... 84 47 79 47 / 50 70 60 50
LOS ALAMOS...................... 85 61 80 61 / 40 50 40 50
PECOS........................... 82 56 75 56 / 40 60 60 60
CERRO/QUESTA.................... 84 52 75 52 / 50 60 60 40
RED RIVER....................... 71 45 69 45 / 80 70 70 50
ANGEL FIRE...................... 76 46 72 46 / 70 70 50 50
TAOS............................ 86 54 81 54 / 40 50 50 40
MORA............................ 80 53 72 53 / 70 70 60 70
ESPANOLA........................ 92 59 85 59 / 30 40 30 40
SANTA FE........................ 89 60 82 60 / 40 50 50 60
SANTA FE AIRPORT................ 91 62 85 62 / 30 40 40 50
ALBUQUERQUE FOOTHILLS........... 92 67 86 67 / 30 30 40 40
ALBUQUERQUE HEIGHTS............. 95 69 89 69 / 20 30 30 40
ALBUQUERQUE VALLEY.............. 96 64 89 64 / 20 30 30 40
ALBUQUERQUE WEST MESA........... 95 65 89 65 / 20 30 30 40
LOS LUNAS....................... 96 63 90 63 / 20 30 30 30
RIO RANCHO...................... 95 66 89 66 / 20 40 30 40
SOCORRO......................... 100 70 93 70 / 10 20 30 30
SANDIA PARK/CEDAR CREST......... 87 59 80 59 / 30 40 40 50
TIJERAS......................... 90 63 83 63 / 30 30 40 50
MORIARTY/ESTANCIA............... 89 56 85 56 / 30 30 30 50
CLINES CORNERS.................. 89 59 82 59 / 30 30 30 50
GRAN QUIVIRA.................... 93 63 84 63 / 20 20 30 30
CARRIZOZO....................... 95 66 85 66 / 10 20 30 30
RUIDOSO......................... 88 59 81 59 / 20 20 40 30
CAPULIN......................... 79 56 72 56 / 80 70 50 40
RATON........................... 83 59 78 59 / 70 60 40 40
SPRINGER........................ 85 58 77 58 / 60 60 40 40
LAS VEGAS....................... 85 57 77 57 / 70 60 50 50
CLAYTON......................... 89 61 78 61 / 60 60 40 30
ROY............................. 87 60 76 60 / 60 70 50 40
CONCHAS......................... 92 65 82 65 / 50 60 30 50
SANTA ROSA...................... 93 66 84 66 / 40 40 30 40
TUCUMCARI....................... 97 67 87 67 / 40 40 30 40
CLOVIS.......................... 95 65 85 65 / 10 20 30 40
PORTALES........................ 97 67 87 67 / 10 20 30 30
FORT SUMNER..................... 97 68 87 68 / 20 20 30 30
ROSWELL......................... 99 70 94 70 / 5 10 10 10
PICACHO......................... 93 65 86 65 / 10 10 20 20
ELK............................. 88 62 82 62 / 10 20 20 20
&&
.ABQ WATCHES/WARNINGS/ADVISORIES...
FLASH FLOOD WATCH FROM NOON MDT TODAY THROUGH THIS EVENING FOR THE
FOLLOWING ZONES...NMZ515-527>534.
&&
$$
AREA FORECAST DISCUSSION...UPDATED
NWS ALBUQUERQUE NM
1152 PM MDT SAT JUL 26 2014
.AVIATION...
06Z TAF CYCLE
EARLIER HIGH RESOLUTION HRRR MODEL GUIDANCE NAILED REDEVELOPMENT
OF CONVECTIVE ACTIVITY LATE THIS EVENING FROM THE RIO GRANDE VALLEY
WESTWARD ACROSS THE CONT DVD. THE BACK DOOR FRONTAL BOUNDARY RACING
SOUTHWEST THRU THE PLAINS WILL SERVE TO FOCUS EVEN MORE DEVELOPMENT
FOR THE NEXT FEW HOURS IN THIS AREA. PLACED VCSH AT MOST TAF SITES
FROM KSAF/KABQ WEST THRU 09-10Z BUT CONFIDENCE WAS NOT HIGH ENOUGH
TO PLACE ANY TEMPO GROUPS AT THIS TIME. LOOK FOR AMENDMENTS WITH TS
IF ANY PARTICULAR AREA BECOMES FAVORED. MID LEVEL CLOUD DECKS WILL
LINGER FOR MUCH OF NORTHERN/WESTERN NM THRU ABOUT 15Z BEFORE SOME
BRIEF CLEARING DEVELOPS. TOMORROW LOOKS TO BE A VERY ACTIVE DAY
ALONG AND NORTH OF I-40 WITH ABUNDANT MOISTURE AND FORCING FROM
THE LOW LEVEL FRONT IN PLACE. HAD TO GO WITH LENGTHY VCTS AROUND
KGUP...AND FROM KLVS TO KTCC. MODELS ARE GENERATING SIGNIFICANT
PRECIP AMOUNTS AFT 00Z FOR THESE AREAS.
GUYER
&&
.PREV DISCUSSION...348 PM MDT SAT JUL 26 2014...
.DISCUSSION...
BIG DIFFERENCE IN SUBSIDENCE INVERSION STRENGTH BETWEEN THIS
MORNINGS AND YESTERDAY MORNINGS SOUNDING TELLING THE STORY.
SIMILAR DEWPOINTS AND SFC HEATING RESULTING IN MUCH MORE CONVECTION
TODAY. BETTER/DEEPER MIXING ALSO ALLOWING TEMPERATURES TO RISE
A FEW DEGREES ABOVE FRIDAY. CLAYTON JUST HIT 100F BREAKING A DAILY RECORD
WITH TUCUMCARI ALREADY UP TO 103F AND ABQ SUNPORT AT 99F.
BACKDOOR FRONT STARTING TO PUSH INTO NORTHEAST COLORADO. THIS
FRONT WILL BECOME THE FOCUS FOR NUMEROUS SHOWERS AND THUNDERSTORMS
FROM THE NORTHERN MOUNTAINS EAST TO THE NORTHEAST HIGHLANDS AND
PLAINS SUNDAY AFTERNOON AND EVENING. LOCALLY HEAVY RAINFALL IS
LIKELY FROM THE EAST SLOPES OF THE SANGRE DE CRISTOS EASTWARD TO
THE TX BORDER AS STORM MOTION IS VERY LIGHT TO NIL AND PWATS IN
THE 1.25-1.50" RANGE. ISSUED FLASH FLOOD WATCH FROM THE EAST
SLOPES OF THE SANGRES EAST THROUGH THE FAR NORTHEAST HIGHLANDS AND
PLAINS. SYNOPTIC SCALE ELY SFC/LOW LEVEL FLOW SUNDAY FORENOON
WILL HELP TRANSPORT MOISTURE WEST INTO CENTRAL AND WRN NM AHEAD OF
THE FRONT...HELPING TO GET SHOWERS AND STORMS GOING IN THESE AREAS
AS WELL. FRONT WILL PLOW THROUGH THE CANYONS OF THE CENTRAL
MOUNTAIN CHAIN EARLY SUNDAY EVENING. A PERIOD OF STRONG EAST
WINDS INTO THE MIDDLE RIO GRANDE VALLEY IS LIKELY AN HOUR OR TWO
PRIOR TO SUNSET CONTINUING THROUGH AT LEAST MIDNIGHT.
LOW LEVEL ELY FLOW CONTINUES TO TRANSPORT LOW LEVEL MOISTURE IN ON
MONDAY. MOST SHOWER AND STORM ACTIVITY WILL SHIFT TO AREAS WEST
OF THE EASTERN PLAINS. 12Z AND 18Z NAM12 BOTH INDICATING THAT AN
MCS WILL DEVELOP OVER THE CENTRAL AND NORTHEAST HIGHLANDS MONDAY
EVENING...THEN SLOWLY PROPAGATE EWD MONDAY NIGHT/TUESDAY MORNING.
A MORE TYPICAL ROUND OF SCATTERED SHOWERS AND THUNDERSTORMS
ANTICIPATED TUESDAY AFTERNOON AND EVENING. NO DISCERNIBLE LARGE SCALE
FORCING TO HELP THINGS BUT PLENTY OF RESIDUAL MOISTURE AND
RELATIVELY LOW HEIGHTS. GFS SHIFTS MOST ACTIVITY TO CENTRAL
MOUNTAIN CHAIN EWD WEDNESDAY THROUGH FRIDAY. UPPER HIGH CONTINUES
TO DRIFT WWD AND WITH SLY TO SELY SFC FLOW...COULD GET STRONG
STORMS EAST OF THE CENTRAL MOUNTAIN CHAIN WEDNESDAY THROUGH AT
LEAST SATURDAY.
33
&&
.FIRE WEATHER...
STUBBORN UPPER LEVEL HIGH STILL CENTERED OVER NEW MEXICO WITH
MONSOON PLUME WEST OF STATE. TODAYS ROUND OF WETTING RAIN TO FAVOR
NORTHERN AND WESTERN ZONES. A PATTERN CHANGE WILL BE IN THE WORKS
STARTING SUNDAY AS THE UPPER RIDGE AMPLIFIES OVER THE WESTERN
STATES...AN UPPER LOW CROSSES THE GREAT LAKES...AND A VIGOROUS BACK
DOOR FRONT MOVES THE EASTERN PLAINS. CHANCES FOR PRECIPITATION
INCREASE ESPECIALLY NORTH AND EAST. THIS AMPLIFIED PATTERN WILL
PERSIST THROUGH THE WORK WEEK SUPPORTING SEVERAL MOIST INTRUSIONS
FROM THE EAST AND A GENERAL UPTICK IN THE WETTING RAIN PATTERN.
SLOW MOVING THUNDERSTORMS WILL PERSIST ACROSS THE WEST AND NORTH
THIS AFTERNOON AND INTO THE EVENING. PRECIPITATION FOOTPRINTS WILL
BE RELATIVELY SMALL. OVERNIGHT RH RECOVERIES TO BE GOOD IN THESE
AREAS WITH FAIR RECOVERIES OVER PORTIONS OF THE NORTHWEST
PLATEAU...THE CENTRAL VALLEYS AND EASTERN HIGHLANDS.
SUNDAY WILL BE A MORE ACTIVE DAY AS THE BACK DOOR FRONT MOVES WELL
INTO THE NORTHEAST PLAINS AND REACHING THE CENTRAL MOUNTAINS BY LATE
MORNING. HEAVY RAIN IS POSSIBLE OVER THE NORTHERN MOUNTAINS AND
NORTHEAST PLAINS. GAP WINDS WILL DEVELOP BY MID DAY THEN STRENGTHEN
BY LATE AFTERNOON AND EARLY EVENING...USHERING LOW LEVEL MOISTURE
INTO THE CENTRAL THEN WESTERN ZONES WITH COOLER TEMPERATURES
STATEWIDE. OVERNIGHT RH RECOVERIES TO IMPROVE AS WELL WITH GOOD TO
EXCELLENT VALUES MOST LOCATIONS.
MOIST LOW LEVEL EAST TO SOUTHEAST WIND PERSISTS ON MONDAY AS THE
MONSOON PLUME MOISTENS UP A BIT AND EDGES TO THE EAST...SETTING UP
OVER EASTERN ARIZONA AND WESTERN NEW MEXICO. THIS WILL SUPPORTING
ANOTHER ROUND OF WETTING RAIN MOST LOCATIONS ON MONDAY...WITH THE
EAST CENTRAL PLAINS SEEING THE LEAST ACTIVITY.
THE REMAINDER OF THE WORK WEEK WILL STAY RELATIVELY ACTIVE WITH
ANOTHER FRONT INTO THE NORTHEAST ON WEDNESDAY AND PERSISTENT MOIST
LOW LEVEL FLOW THURSDAY INTO FRIDAY. TEMPERATURES TO REMAIN NEAR
NORMAL OR BELOW ACROSS THE EAST.
05
&&
.ABQ WATCHES/WARNINGS/ADVISORIES...
FLASH FLOOD WATCH FROM SUNDAY AFTERNOON THROUGH SUNDAY EVENING FOR
THE FOLLOWING ZONES...NMZ515-527-528-530-531.
&&
$$
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
437 AM EDT SUN JUL 27 2014
.SYNOPSIS...
A SERIES OF LOW PRESSURE SYSTEMS WILL TRACK FROM THE MIDWEST TO
THE EAST COAST THROUGH MONDAY BRINGING INCREASINGLY HUMID AIR TO
THE AREA ALONG WITH A GOOD CHANCE OF SHOWERS AND THUNDERSTORMS.
THE BEST CHANCE FOR A WIDESPREAD RAIN LOOKS TO BE SUNDAY NIGHT
INTO MONDAY. COOLER AND DRYER WEATHER WILL FOLLOW BEHIND THESE
SYSTEMS TUESDAY AND WEDNESDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
RADARS SHOW SOME SCATTERED RAIN SHOWERS JUST CLIPPING FAR NORTHEAST
ONEIDA COUNTY AT THIS TIME. THESE SHOWERS WERE EXITING NORTH CENTRAL
NEW YORK AS A WEAKENING UPPER LEVEL WAVE CONTINUES TO TRACK EASTWARD
TOWARD NEW ENGLAND. WATER VAPOR IMAGERY SHOWS A MUCH MORE SUBSTANTIAL
SHORT WAVE PRESENTLY OVER LOWER MICHIGAN AND LAKE HURON. THIS
FEATURE WAS CAPTURED WELL IN THE TROPOPAUSE PRESSURE FIELDS FOR THE
1.5 PV UNIT ON THE LATEST RAP MODEL. THIS FEATURE IS PROJECTED TO
TRACK INTO CENTRAL NY BY 12Z. RADAR SHOWS A SWATH OF SHOWERS AND
THUNDERSTORMS OVER ONTARIO WITH MUCH LESS SOUTHWARD. THE HI RES
MESOSCALE MODELS ARE HAVING TROUBLE SIMULATING THE PRESENT RADAR
COVERAGE THUS FEEL THEY LIKELY ARE A BIT SUSPECT. THE HRRR HAS THE
BEST HANDLE SO FAR AND LIKE THE OTHER HI RESOLUTION MODELS BRINGS A
SWATH OF SHOWERS AND THUNDERSTORMS ACRS CENTRAL NY BTWN 9 AND 12Z.
SO AS THIS WAVE PASSES BY LATER THIS MORNING, I WILL HAVE LIKELY
POPS IN NC NY AND TAPER THEM DOWN TO CHC IN NE PA.
AFTER THIS WAVE PASSES AFTER 12Z...CENTRAL NY AND NORTHEAST PA GETS
INTO A LULL WITH MID-LEVEL SUBSIDENCE. MODELS ALL SHOW A NICE
LOW-LEVEL JET FEATURE TRANSPORTING LOW-LEVEL MOISTURE NORTHWARD
DURING THE ERLY MORNING HOURS WITH THE WAVE THAT WILL PASS ACRS C NY
MENTIONED ABV. HENCE DWPTS ABV THE SURFACE WILL BE HIGH ENOUGH TO MIX
DOWN MID TO UPPER 60S DEWPOINTS WITH INSOLATION LATER IN THE MORNING
AND AFTERNOON. SOME LOCALES LIKELY WILL HAVE SFC DEWPOINTS IN THE LOWER 70S.
EVENTUALLY BY AFTERNOON THERE WILL BE ENUF SUNSHINE FOR SIGNIFICANT
INSTABILITY TO DEVELOP. I EXPECT CAPES BETWEEN 1000 AND 2000 J/KG
MIXED LAYER. THE WIND SHEAR INITIALLY THIS AFTERNOON IS FAVORABLE
FOR SEVERE WINDS AND POTENTIAL LARGE HAIL. HOWEVER...THERE IS NO
REAL TRIGGER TO FOCUS ANY CONVECTION THIS AFTERNOON. GIVEN THE
POTENTIAL WE CAN NOT RULE OUT AN ISOLATED TO SCT THUNDERSTORM AND
KEPT POPS IN OUR GRIDS BUT BELIEVE BULK OF ACVTY WILL COME SUNDAY
EVENING AND SUNDAY NIGHT AND NEXT MAJOR WAVE AFFECTS THE REGION.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH TUESDAY NIGHT/...
WATER VAPOR IMAGERY SHOWS AN UNSEASONABLY VIGOUROUS UPPER LEVEL
LOW RAPIDLY MOVING SOUTHEASTWARD INTO NORTHERN MINN AT THIS TIME.
THIS FEATURE WILL CONTINUE TO DROP SOUTHEASTWARD TODAY AND REACH
OHIO BY 03Z MONDAY AND OPEN UP INTO A TROUGH. THIS FEATURE WILL
PROVIDE THE UPPER LEVEL SUPPORT TO FIRE CONVECTION. THE WAVE WILL
WORK ON SIGNIFICANT INSTABILITY OVER THE LWR OHIO VALLEY TO CNTRL
APPLCNS THIS AFTERNOON AND HENCE SPC/S MODERATE RISK FOR SEVERE
WEATHER DOWN THERE. AS THIS UPPER LEVEL WAVE BEGINS TO TRACK E
INTO PA BTWN 3 AND 6Z...THE INSTABILITY WILL BE WEAKER BUT STILL,
GIVEN THE UPPER LEVEL SUPPORT, AND MIXED LAYER CAPES STILL BETWEEN
1000 AND 2000 J/KG IN NE PA AND SC NY...I THINK THERE WILL BE A
BAND OF STRONG TO SEVERE THUNDERSTORMS WORKING NORTHEAST FROM C PA
INTO NE PA AND EVENTUALLY SC NY BEFORE IT WEAKENS AND STATIFORMS
OUT IN C NY BY 6Z. STILL CONCUR WITH SPC SLGHT RISK...ESPECIALLY
FROM SC NY TO NE PA IN THE WFO BGM FORECAST AREA. FARTHER N...BY
THE TIME THE INFLUENCE OF THIS WAVE REACHES NC NY...INSTABILITY
WILL BE LESS AND THE SHEAR WON/T BE AS STRONG. BUT IN ANY EVENT
WILL CONT TO MENTION CHC FOR SVR THUNDERSTORMS IN HWO MAINLY SUN
EVENING AND NOT TAKE NC NY OUT JUST YET.
THEN BETWEEN 6Z-12Z MON THINGS GET INTERESTING. DUE TO THE DIGGING
UPPER LEVEL TROF AND CONVECTION...ALL SYNOPTIC MODELS INDICATE
THAT A LOW-LEVEL CYCLONE WILL DEVELOP FROM NW PA TO NJ. BY 12Z THE
4 MAIN SYNOPTIC MODELS...EURO...CMC...NAM AND GFS ALL DIFFER IN
THE TIMING OF THE SFC LO. THE EURO IS SLOWEST IN BRINGING IT TO SE
NY BY 18Z MON...WITH THE GFS THE FASTEST HAVING THE SFC LO OVER
NH AT THIS TIME. THE OTHER TWO MODELS ARE IN BETWEEN.
IN ANY EVENT...THE DEVELOPMENT OF THIS LOW-LEVEL CYCLONE WILL PUT
A DEFORMATION ZONE WITH SIGNIFICENT FGEN FORCING ON THE NW SIDE OF
IT...WHICH AS PER NAM...GFS...AND CMC HAS A SWATH OF HEAVY RAIN
FOR PORTIONS OF C NY AND NRN PA BTWN 6Z AND 18Z MONDAY. THE EURO
IS FARTHER W WITH THIS AXIS OF HEAVIER PRECIP. THE INTERESTING
ASPECT OF THIS THAT THERE IS A SLOPED LAYER OF FGEN FORCING ON THE
NW SIDE OF THE LOW WITH CONVECTIVE INSTABILITY ALOFT. THIS COULD
MEAN THAT AS THE BAND OF POTENTIALLY STRONG TO SEVERE STORMS THAT WORKS
NORTHEAST ACR NE PA AND SC NY...SLOWS DOWN AND EVENTUALLY BECOMES
A HEAVY RAIN PRODUCER AS IT STRATIFORMS OUT. THE NAM HAS THE
HIGHEST QPF WITH 2.5 TO 3.5 INCHES ACRS C NY. THE OTHER MODELS ARE
TAMER BUT STILL HAVE UP TO 2 INCHES OR MORE. THIS COULD MEAN LOCALLY
THAT RAINFALL WHICH COULD EXCEED THREE OR EVEN FOUR INCHES LOCALLY SO
WILL HAVE TO WATCH OUT FOR THE POTENTIAL FOR FLASH FLOODING SUN
NGT AS WELL. WILL MENTION IN HWO.
FOR MONDAY DURING THE DAY...THE SFC LO PULLS OUT TO THE NE AND THE
RAINFALL STARTS TO WIND DOWN FROM SW-NE LATE IN THE DAY. THE EURO IS
SLOWEST BRINGING THE PRECIP OUT WITH THE NAM AND GFS THE FASTEST.
WILL MAINTAIN LINGERING SHRA MOST OF THE DAY AS PER SURROUNDING
OFFICES GRIDS. WOULDNT BE SURPRISED IF PRECIP ENDS A BIT QUICKER
THAN CURRENTLY ADVERVISED MON PM THOUGH.
FOR MON NGT...ONLY THE EURO HAS LINGERING PRECIP FOR THE CATSKILLS
TO THE UPPER MOHAWK VALLEY. REST OF MODELS ARE BASICALLY DRY. FOR
NOW WILL GO WITH EURO/S AND SURROUNDING OFFICES IDEA OF SLGHT CHC
TO CHC SHRA MON EVE...THEN END PRECIP AFTER MIDNIGHT INTO ERLY
TUESDAY.
FOR TUE... HAVE POP UP SHRA GIVEN THE COLDER AIR ALOFT. TUE NGT
WILL SEE HIGH PRESSURE AND FAIR WEATHER. A FEW LINGERING SHRA
STILL POSSIBLE IN THE FINGER LAKES REGION CLOSER TO THE NEXT WAVE.
&&
.LONG TERM /WEDNESDAY THROUGH SATURDAY/...
430 AM UPDATE...NO SIGNIFICANT CHANGES TO EXTENDED JUST REFRESHED
WITH LATEST WPC GUIDANCE. UPPER LEVEL TROF AXIS WILL REMAIN JUST
WEST OF AREA THROUGHOUT PERIOD. EACH DAY WILL CONTINUE TO CARRY
SLIGHT CHC/CHC POPS DURING THE AFTERNOON FOR DIURNAL CONVECTION
UNDER AN EVER PERSISTENT EASTERN TROF. TEMPS WILL RUN SEVERAL
DEGREES BELOW SEASONAL LEVELS.
145 PM UPDATE...
HIPRES AT THE SFC WL BE OVR THE CWA AT THE START OF THE LONG TERM
PD. HWVR FLOW ALOFT WL BE DOMINATED BY A L/WV TROF. THIS WL KEEP
SLGT CHCS FOR AFTN SHRA/TSRA THRU THE END OF THE WEEK AND GIVE
CREDENCE TO THE WORDS "DIRTY HIGH." HV BASICALLY FOLLOWED WPC
GUIDANCE WITH 20 POPS EACH AFTN ALONG WITH NR NORMAL TEMPS, WITH
HIGHS ARND 80 AND LOWS IN THE 50S EXPECTED EACH PERIOD.
&&
.AVIATION /09Z SUNDAY THROUGH THURSDAY/...
A MID LEVEL SHORT WAVE MOVING THROUGH THE EASTERN GREAT LAKES MAY
PRODUCE MVFR SHOWERS AT KRME/KSYR BETWEEN 08Z-12Z. OTHERWISE
GENERALLY VFR CONDITIONS EARLY THIS MORNING WITH OCCASIONAL MVFR
CIGS AROUND DAYBREAK UNDER INCREASINGLY MOIST SOUTHWEST FLOW. BY
MID MORNING ANY RESTRICTIONS WILL LIFT WITH SCT/BKN CONDITIONS
AROUND 4-5K FT. ISOLATED CONVECTION IS POSSIBLE THIS AFTERNOON BUT
NOT INCLUDED DUE TO VERY LIMITED AREAL COVERAGE. THIS EVENING A
DEEP UPPER LEVEL TROF AND ASSOCIATED SFC LOW WILL BRING WIDESPREAD
MODERATE SHOWERS TO THE TERMINALS. ACROSS THE SOUTHERN TERMINALS
BEGAN THIS ACTIVITY AROUND 00Z AND LEFT OUT OF KSYR/KRME AS IT
WILL BEGIN TOWARD END OFF TAF PERIOD.
S/SW WINDS EARLY THIS MORNING AROUND 5-8 KNOTS EXCEPT SE AT KRME.
AFTER MID MORNING SOUTHWEST WINDS AROUND 10 KNOTS BECOMING LIGHT
AND VARIABLE OVERNIGHT.
OUTLOOK...
MON-MON NGT...POTENTIAL RESTRICTIONS IN SHRA/TSRA.
TUE-THU...RESTRICTIONS POSSIBLE EACH AFTERNOON IN SHRA.
&&
.BGM WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NY...NONE.
&&
$$
SYNOPSIS...DJN
NEAR TERM...DJN
SHORT TERM...DJN
LONG TERM...PVN/RRM
AVIATION...RRM
AREA FORECAST DISCUSSION
NWS BURLINGTON VT
422 AM EDT SUN JUL 27 2014
.SYNOPSIS...
AN ACTIVE PERIOD OF WEATHER IS EXPECTED ACROSS THE NORTH COUNTRY
WITH SEVERAL ROUNDS OF SHOWERS WITH EMBEDDED THUNDERSTORMS LIKELY.
FIRST ROUND ARRIVES LATE TONIGHT INTO SUNDAY...WITH ADDITIONAL
SHOWERS ON MONDAY INTO TUESDAY. DAYTIME HIGH TEMPERATURES WILL BE
SLIGHTLY BELOW NORMAL...WITH SLIGHTLY ABOVE NORMAL OVERNIGHT
LOWS...DUE TO CLOUDS. IN ADDITION...AN INCREASE IN THE RELATIVE
HUMIDITY VALUES WILL OCCUR BY SUNDAY AFTERNOON.
&&
.NEAR TERM /UNTIL 7 PM THIS EVENING/...
AS OF 1252 AM EDT SUNDAY...GIVEN INCREASING AREAL COVERAGE OF
SHOWERS PER COMPOSITE RADAR IMAGERY...I`VE ADJUSTED POPS AND WX TO
REFLECT AREAL COVERAGE WORDING. MID-LEVEL SHORTWAVE TROUGH EVIDENT
IN WV IMAGERY ACROSS LAKE HURON PRIMARILY RESPONSIBLE FOR THIS
INCREASE IN AREAL COVERAGE OF SHOWERS NOW ACROSS NORTHERN NEW
YORK. I ALSO NOTE A RATHER SOLID LINE OF HEAVIER SHOWERS AND
EMBEDDED THUNDERSTORMS APPROACHING THE NORTHWESTERN SHORE OF LAKE
ONTARIO - ASSOCIATED WITH A ZONE OF SLIGHTLY NEGATIVE SHOWALTER
INDICES (-1 TO -2) PER 03Z RAP ANALYSES IN ADDITION TO
AFOREMENTIONED MID- LEVEL SHORTWAVE. THOSE NEGATIVE SHOWALTERS ARE
PROGGED TO TRANSLATE EASTWARD...LIKELY KEEPING A THUNDER THREAT
GOING AS IT MOVES EAST EARLY THIS MORNING. HRRR AND WRF-ARW APPEAR
TO HAVE THE BEST HANDLE ON ONGOING ACTIVITY. EXTRAPOLATION OF THE
MORE SOLID LINE OF SHOWERS AND STORMS INTO ST. LAWRENCE VALLEY
NEXT COUPLE HOURS...ADIRONDACKS BY THE PRE- DAWN
HOURS/SUNRISE...AND CHAMPLAIN VALLEY AROUND 6-7 AM. UNTIL
THEN...EXPECT SCATTERED SHOWERS TO GRADUALLY SPREAD EAST. CHANGE
IN WX GRIDS ESSENTIALLY STATES SCATTERED TO NUMEROUS
SHOWERS...WITH SCATTERED T-STORMS TIED TO HIGHEST POP (70-80%).
OTHERWISE...MADE MOSTLY MINOR ADJUSTMENTS TO LOWS ACROSS EAST VT
AND THE ADIRONDACKS.
&&
.SHORT TERM /7 PM THIS EVENING THROUGH TUESDAY/...
AS OF 335 PM EDT SATURDAY...ACTIVE WEATHER PERIOD ANTICIPATED WITH PERIODS
OF OCCASIONAL SHOWERS WITH SOME EMBEDDED THUNDERSTORMS EXPECTED. FORECAST
FOCUS WILL BE TIMING OF PRECIPITATION AND POTENTIAL FOR A FEW STRONGER
STORMS ON SUNDAY...IF ENOUGH INSTABILITY CAN DEVELOP. ON SUNDAY...1ST
S/W ENERGY AND ASSOCIATED PRECIPITATION WILL EXIT VT BY 15Z. QUESTION
WILL BE HOW MUCH CLEARING DEVELOPS ON SUNDAY AFTERNOON TO CAUSE SURFACE
HEATING AND INCREASE OUR INSTABILITY PARAMETERS. MODELS VARY ON THIS
GREATLY WITH THE LOCAL BTV4 SHOWING CAPE VALUES BETWEEN 1500 AND 1800
J/KG...WHILE NAM12 IS BETWEEN 1000 AND 1200 J/KG AND THE GFS VALUES
RANGE FROM 800 TO 1000 J/KG...WITH ALL MODELS SUGGESTING 0 TO 6 KM
SHEAR VALUES BETWEEN 30 AND 40 KNOTS ON SUNDAY AFTERNOON. THINKING
ENOUGH INSTABILITY WILL DEVELOP TO PROMOTE CONVECTIVE UPDRAFTS
WITH A FEW STRONGER STORMS POSSIBLE. HOWEVER...SYNOPTIC SCALE
FORCING WILL BE MINIMAL AFTER MORNING S/W ENERGY EXITS OUR
AREA...BUT LEFTOVER OUTFLOW BOUNDARIES AND TERRAIN WILL BE FOCUS
FOR AFTERNOON SHOWERS/STORM DEVELOPMENT. WILL MENTION LIKELY POPS
EASTERN/CENTRAL OUR AREA THROUGH 15Z...THEN TAPER TO CHANCE POPS
WITH HIGHEST VALUES ACROSS THE MOUNTAINS. A FEW STRONGER STORMS
WILL BE CAPABLE OF PRODUCING SMALL HAIL AND BRIEF GUSTY
WINDS...BUT AREAL COVERAGE WILL BE LIMITED THEREFORE WILL NOT
MENTION IN GRIDS...BUT WILL IN THE HAZARDOUS WEATHER OUTLOOK.
PROGGED 85H TEMPS BETWEEN 12-14C ON SUNDAY WITH SOME SUN/MIXING
SHOULD SUPPORT AFTERNOON HIGHS IN THE M70S MOUNTAINS/NEK TO
U70S/L80S WARMER VALLEYS.
FOR SUNDAY NIGHT THROUGH MONDAY NIGHT...LARGE SCALE SYNOPTIC PATTERN
SHOWS A DEVELOPING FULL LATITUDE TROF ACROSS THE EASTERN CONUS...WHILE
RIDGE BUILDS ACROSS THE INTER-MOUNTAIN WEST. THIS DEEP TROF WILL RESULT
IN UNSETTLED WEATHER ACROSS OUR OUR AREA...WITH A WIDESPREAD WETTING
RAINFALL EVENT LIKELY ON SUNDAY NIGHT INTO MONDAY. POTENT S/W
ENERGY WILL DIG ACROSS THE CENTRAL GREAT LAKES ON SUNDAY EVENING
AND BE LOCATED OVER SOUTHERN NEW ENGLAND BY 12Z MONDAY...WHILE A
NEGATIVELY TITLED 7/5H TROF DEVELOPS. THIS ENERGY...COMBINED WITH
DEVELOPING NEGATIVELY TILTED MID/UPPER LEVEL TROF AND SURFACE LOW
PRES TRACKING FROM NW PA TO CENTRAL NEW ENGLAND WILL PRODUCE A
MODERATE RAINFALL EVENT ACROSS OUR OUR AREA. THIS SYNOPTIC SETUP
DURING THE WINTER MONTHS WOULD HAVE RESULTED IN A NICE
ACCUMULATING SNOWFALL. LIKE MOST WINTER STORMS...THIS SYSTEM WILL
COME IN 2 PARTS...1ST WILL BE MID LEVEL WAA AND ASSOCIATED
LIFT/MOISTURE BTWN 06Z-12Z MONDAY...WITH BRIEF BREAK...BEFORE WRAP
AROUND MID LEVEL MOISTURE AND DEFORMATION ZONES DEVELOPS ON
BACKSIDE AFT 18Z MONDAY. STILL SOME QUESTION IF INSTABILITY CAN
DEVELOP IN DRY SLOT ON MONDAY...FOR POTENTIAL STORMS. THINKING
PLENTY OF LOW LEVEL MOISTURE AND CLOUDS WILL LIMIT SURFACE
HEATING...ESPECIALLY WITH SURFACE LOW TRACKING TO OUR
SOUTH...PLACING MOST OF OUR OUR AREA ON THE COOL SIDE OF THE
STORM. HAVE NOTED THE 12Z GFS SHOWING SURFACE BASED CAPE BTWN 1500
AND 1800 J/KG ACROSS CENTRAL/EASTERN VT ON MONDAY
AFTERNOON...WHICH COMBINED WITH POSITION OF POTENT 5H VORT AND
AVAILABLE MOISTURE WOULD SUPPORT SOME THUNDERSTORM DEVELOPMENT.
THIS POTENTIAL WILL NEED TO BE WATCHED CAREFULLY ESPECIALLY IF
SURFACE LOW PRES TRACKS FURTHER WEST AND PLACES OUR OUR AREA IN
THE WARM SECTOR ON MONDAY AFTERNOON...WITH GREATER INSTABILITY. A
GENERAL LIGHT TO MODERATE RAIN WILL OCCUR ON MONDAY NIGHT...ASSOCIATED
WITH BACK SIDE DEFORMATION. BOTH GFS/NAM SHOW GOOD RIBBON OF 850
TO 500MB RH WITH SOME ENHANCED 850 TO 700MB UVVS ACROSS THE
CHAMPLAIN VALLEY AND POINTS EAST. QPF WILL RANGE FROM 0.25 TO 0.50
ACROSS THE SAINT LAWRENCE VALLEY TO 0.50 TO 1.50" ACROSS THE
ADIRONDACKS INTO EASTERN VT. NO WIDESPREAD HYDRO ISSUES ARE
ANTICIPATED ATTM. TEMPS WILL BE TRICKY AND HIGHLY DEPEND UPON
AMOUNT OF SUNSHINE ON MONDAY...THINKING MAINLY 60S MOUNTAINS TO
70S VALLEYS WITH LOWS GENERALLY IN THE 50S TO NEAR 60F.
&&
.LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/...
AS OF 421 AM EDT SUNDAY...
A SLOW WARMING TREND TO NEAR NORMAL TEMPERATURES IS EXPECTED BY THE
END OF THE WEEK WITH THE HIGHEST CHANCE OF SHOWERS AND THUNDERSTORMS
ON THURSDAY.
MODELS IN GOOD AGREEMENT THAT A DEEP LARGE SCALE TROUGH WILL
REMAIN OVER THE EASTERN US CENTERED NEAR 80 DEG W WITH A RIDGE OVER
THE INTER-MOUNTAIN WEST THROUGHOUT THE PERIOD...THOUGH WEAKENING
WITH RISING HEIGHTS.
THOUGH A SHOWER CAN`T BE COMPLETELY RULED OUT ANY AFTERNOON DURING THIS
PERIOD WITH THE UPPER TROUGH JUST OFF TO THE WEST...THE BEST
CHANCE FOR SEEING SHOWERS AND THUNDERSTORMS WILL BE THURSDAY
AFTERNOON AS A SHORT WAVE WITH COLD AIR ALOFT SWINGS ACROSS THE
AREA WITH SOME INSTABILITY AND SOME QG FORCING.
THE UPPER TROUGH WEAKENS BUT REMAINS IN PLACE FRIDAY INTO THE
WEEKEND BUT RETROGRADES A FEW DEGREES WESTWARD IN RESPONSE TO A
BUILDING ATLANTIC RIDGE ALOFT, RISING HEIGHTS OVER THE EAST COAST
WITH A BERMUDA HIGH STRENGTHENING AT THE SURFACE...WHICH IS FAIRLY
TYPICAL FOR LATE SUMMER. SOME SMALL CHANCE OF SHOWERS AND
THUNDERSTORMS WILL CONTINUE EACH DAY AS AREA REMAINS LOCKED INTO THE
EASTERN SIDE OF THE UPPER TROF.
SLIGHTLY BELOW NORMAL MAX TEMPS ARE EXPECTED WEDNESDAY WITH PARTLY
SUNNY SKIES. HIGHS TEMPS MAINLY IN THE 70S WITH 850 TEMPS ONLY
AROUND 8-10C.
850 MB TEMPS WARM A COUPLE DEGREES EACH DAY SO THAT BY THURSDAY
THROUGH SATURDAY SHOULD BE 12-14C. WITH PARTIAL SUN UNDER DIURNAL
CUMULUS CLOUDS EXPECT HIGHS MODERATING TO NEAR NORMAL -
UPPER 70S LOWER 80S.
&&
.AVIATION /08Z SUNDAY THROUGH THURSDAY/...
THROUGH 06Z MONDAY..TRENDING MVFR EARLY THIS MORNING WITH SHOWERS
ALREADY OVER THE REGION AND WITH THUNDERSTORMS MOVING INTO THE
REGION FROM ONTARIO ASSOCIATED WITH A WEAK WARM FRONT.
CHANCE OF SHOWERS ARE NEAR 80 PERCENT THROUGH ABOUT 15Z TODAY THEN DECREASE.
CHANCES OF THUNDER ARE INCREASING ESPECIALLY FROM SLK TO BTV AND
RUT TO MPV MOVING WEST TO EAST 09-13Z BUT WILL HANDLE WITH
AMENDMENTS AS IT REMAINS TO BE SEEN EXACTLY WHERE THE
THUNDERSTORMS TRACK AND IF THEY HOLD TOGETHER.
VISIBILITIES EXPECTED TO REMAIN MAINLY VFR...EXCEPT SOME BRIEF
REDUCTIONS TO MVFR/IFR POSSIBLE IN ANY HEAVIER SHOWERS OR ISOLATED
THUNDERSTORMS.
CEILINGS WILL GRADUALLY LOWER AND PERIODS OF MVFR ARE LIKELY ON
BACK SIDE OF RAIN SHOWERS...LASTING UNTIL LATE MORNING WHEN SHOWER
THREAT DECREASES. CEILINGS LIFT BACK TO VFR BY SUNDAY AFTERNOON.
SCATTERED SHOWER AND ISOLATED THUNDERSTORM DEVELOPMENT POSSIBLE
AGAIN SUNDAY AFTERNOON/EVENING AHEAD OF A SLOW SOUTHWARD MOVING
COLD FRONT IN CANADA. WILL SHOW WITH VCSH/VCTS FOR NOW AS PROBABILITIES
DROP TO 20-30 PERCENT.
SHOWER AND THUNDER CHANCES DROP THIS EVENING UNDER VFR CONDITIONS.
COULD BE SOME FG/BR CHANCES LATER TONIGHT IF CLEARING SKIES AND
LIGHT WINDS PREVAIL AS FRONTAL SYSTEM STALLS TO OUR NORTH.
LIGHT SOUTH WINDS TONIGHT TURN SOUTH/SOUTHWEST ON SUNDAY FROM 5 TO
10 KNOTS. SOME GUSTS TO 20 KNOTS POSSIBLE.
OUTLOOK 06Z MONDAY THROUGH THURSDAY...
06Z MON - 12Z TUE...PERIODS OF MVFR IN RAIN SHOWERS AND ISOLATED
THUNDERSTORMS. LOCAL IFR POSSIBLE.
12Z TUE - 12Z THU...TRENDING VFR. POSSIBLE IFR/LOWER VISIBILITY IN
OVERNIGHT FOG/MIST MPV AND SLK.
12Z THU ONWARD...MAINLY VFR ALTHOUGH BRIEF PERIODS OF MVFR
POSSIBLE IN SCATTERED SHOWERS...MAINLY SLK/MSS.
&&
.BTV WATCHES/WARNINGS/ADVISORIES...
VT...NONE.
NY...NONE.
&&
$$
SYNOPSIS...LOCONTO
NEAR TERM...LOCONTO
SHORT TERM...LOCONTO
LONG TERM...SISSON
AVIATION...SISSON
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
323 AM EDT SUN JUL 27 2014
.SYNOPSIS...
A SERIES OF LOW PRESSURE SYSTEMS WILL TRACK FROM THE MIDWEST TO
THE EAST COAST THROUGH MONDAY BRINGING INCREASINGLY HUMID AIR TO
THE AREA ALONG WITH A GOOD CHANCE OF SHOWERS AND THUNDERSTORMS.
THE BEST CHANCE FOR A WIDESPREAD RAIN LOOKS TO BE SUNDAY NIGHT
INTO MONDAY. COOLER AND DRYER WEATHER WILL FOLLOW BEHIND THESE
SYSTEMS TUESDAY AND WEDNESDAY.
&&
.NEAR TERM /THROUGH TODAY/...
RADARS SHOW SOME SCATTERED RAIN SHOWERS JUST CLIPPING FAR NORTHEAST
ONEIDA COUNTY AT THIS TIME. THESE SHOWERS WERE EXITING NORTH CENTRAL
NEW YORK AS A WEAKENING UPPER LEVEL WAVE CONTINUES TO TRACK EASTWARD
TOWARD NEW ENGLAND. WATER VAPOR IMAGERY SHOWS A MUCH MORE SUBSTANTIAL
SHORT WAVE PRESENTLY OVER LOWER MICHIGAN AND LAKE HURON. THIS
FEATURE WAS CAPTURED WELL IN THE TROPOPAUSE PRESSURE FIELDS FOR THE
1.5 PV UNIT ON THE LATEST RAP MODEL. THIS FEATURE IS PROJECTED TO
TRACK INTO CENTRAL NY BY 12Z. RADAR SHOWS A SWATH OF SHOWERS AND
THUNDERSTORMS OVER ONTARIO WITH MUCH LESS SOUTHWARD. THE HI RES
MESOSCALE MODELS ARE HAVING TROUBLE SIMULATING THE PRESENT RADAR
COVERAGE THUS FEEL THEY LIKELY ARE A BIT SUSPECT. THE HRRR HAS THE
BEST HANDLE SO FAR AND LIKE THE OTHER HI RESOLUTION MODELS BRINGS A
SWATH OF SHOWERS AND THUNDERSTORMS ACRS CENTRAL NY BTWN 9 AND 12Z.
SO AS THIS WAVE PASSES BY LATER THIS MORNING, I WILL HAVE LIKELY
POPS IN NC NY AND TAPER THEM DOWN TO CHC IN NE PA.
AFTER THIS WAVE PASSES AFTER 12Z...CENTRAL NY AND NORTHEAST PA GETS
INTO A LULL WITH MID-LEVEL SUBSIDENCE. MODELS ALL SHOW A NICE
LOW-LEVEL JET FEATURE TRANSPORTING LOW-LEVEL MOISTURE NORTHWARD
DURING THE ERLY MORNING HOURS WITH THE WAVE THAT WILL PASS ACRS C NY
MENTIONED ABV. HENCE DWPTS ABV THE SURFACE WILL BE HIGH ENOUGH TO MIX
DOWN MID TO UPPER 60S DEWPOINTS WITH INSOLATION LATER IN THE MORNING
AND AFTERNOON. SOME LOCALES LIKELY WILL HAVE SFC DEWPOINTS IN THE LOWER 70S.
EVENTUALLY BY AFTERNOON THERE WILL BE ENUF SUNSHINE FOR SIGNIFICANT
INSTABILITY TO DEVELOP. I EXPECT CAPES BETWEEN 1000 AND 2000 J/KG
MIXED LAYER. THE WIND SHEAR INITIALLY THIS AFTERNOON IS FAVORABLE
FOR SEVERE WINDS AND POTENTIAL LARGE HAIL. HOWEVER...THERE IS NO
REAL TRIGGER TO FOCUS ANY CONVECTION THIS AFTERNOON. GIVEN THE
POTENTIAL WE CAN NOT RULE OUT AN ISOLATED TO SCT THUNDERSTORM AND
KEPT POPS IN OUR GRIDS BUT BELIEVE BULK OF ACVTY WILL COME SUNDAY
EVENING AND SUNDAY NIGHT AND NEXT MAJOR WAVE AFFECTS THE REGION.
&&
.SHORT TERM /TONIGHT THROUGH TUESDAY NIGHT/...
WATER VAPOR IMAGERY SHOWS AN UNSEASONABLY VIGOUROUS UPPER LEVEL
LOW RAPIDLY MOVING SOUTHEASTWARD INTO NORTHERN MINN AT THIS TIME.
THIS FEATURE WILL CONTINUE TO DROP SOUTHEASTWARD TODAY AND REACH
OHIO BY 03Z MONDAY AND OPEN UP INTO A TROUGH. THIS FEATURE WILL
PROVIDE THE UPPER LEVEL SUPPORT TO FIRE CONVECTION. THE WAVE WILL
WORK ON SIGNIFICANT INSTABILITY OVER THE LWR OHIO VALLEY TO CNTRL
APPLCNS THIS AFTERNOON AND HENCE SPC/S MODERATE RISK FOR SEVERE
WEATHER DOWN THERE. AS THIS UPPER LEVEL WAVE BEGINS TO TRACK E
INTO PA BTWN 3 AND 6Z...THE INSTABILITY WILL BE WEAKER BUT STILL,
GIVEN THE UPPER LEVEL SUPPORT, AND MIXED LAYER CAPES STILL BETWEEN
1000 AND 2000 J/KG IN NE PA AND SC NY...I THINK THERE WILL BE A
BAND OF STRONG TO SEVERE THUNDERSTORMS WORKING NORTHEAST FROM C PA
INTO NE PA AND EVENTUALLY SC NY BEFORE IT WEAKENS AND STATIFORMS
OUT IN C NY BY 6Z. STILL CONCUR WITH SPC SLGHT RISK...ESPECIALLY
FROM SC NY TO NE PA IN THE WFO BGM FORECAST AREA. FARTHER N...BY
THE TIME THE INFLUENCE OF THIS WAVE REACHES NC NY...INSTABILITY
WILL BE LESS AND THE SHEAR WON/T BE AS STRONG. BUT IN ANY EVENT
WILL CONT TO MENTION CHC FOR SVR THUNDERSTORMS IN HWO MAINLY SUN
EVENING AND NOT TAKE NC NY OUT JUST YET.
THEN BETWEEN 6Z-12Z MON THINGS GET INTERESTING. DUE TO THE DIGGING
UPPER LEVEL TROF AND CONVECTION...ALL SYNOPTIC MODELS INDICATE
THAT A LOW-LEVEL CYCLONE WILL DEVELOP FROM NW PA TO NJ. BY 12Z THE
4 MAIN SYNOPTIC MODELS...EURO...CMC...NAM AND GFS ALL DIFFER IN
THE TIMING OF THE SFC LO. THE EURO IS SLOWEST IN BRINGING IT TO SE
NY BY 18Z MON...WITH THE GFS THE FASTEST HAVING THE SFC LO OVER
NH AT THIS TIME. THE OTHER TWO MODELS ARE IN BETWEEN.
IN ANY EVENT...THE DEVELOPMENT OF THIS LOW-LEVEL CYCLONE WILL PUT
A DEFORMATION ZONE WITH SIGNIFICENT FGEN FORCING ON THE NW SIDE OF
IT...WHICH AS PER NAM...GFS...AND CMC HAS A SWATH OF HEAVY RAIN
FOR PORTIONS OF C NY AND NRN PA BTWN 6Z AND 18Z MONDAY. THE EURO
IS FARTHER W WITH THIS AXIS OF HEAVIER PRECIP. THE INTERESTING
ASPECT OF THIS THAT THERE IS A SLOPED LAYER OF FGEN FORCING ON THE
NW SIDE OF THE LOW WITH CONVECTIVE INSTABILITY ALOFT. THIS COULD
MEAN THAT AS THE BAND OF POTENTIALLY STRONG TO SEVERE STORMS THAT WORKS
NORTHEAST ACR NE PA AND SC NY...SLOWS DOWN AND EVENTUALLY BECOMES
A HEAVY RAIN PRODUCER AS IT STRATIFORMS OUT. THE NAM HAS THE
HIGHEST QPF WITH 2.5 TO 3.5 INCHES ACRS C NY. THE OTHER MODELS ARE
TAMER BUT STILL HAVE UP TO 2 INCHES OR MORE. THIS COULD MEAN LOCALLY
THAT RAINFALL WHICH COULD EXCEED THREE OR EVEN FOUR INCHES LOCALLY SO
WILL HAVE TO WATCH OUT FOR THE POTENTIAL FOR FLASH FLOODING SUN
NGT AS WELL. WILL MENTION IN HWO.
FOR MONDAY DURING THE DAY...THE SFC LO PULLS OUT TO THE NE AND THE
RAINFALL STARTS TO WIND DOWN FROM SW-NE LATE IN THE DAY. THE EURO IS
SLOWEST BRINGING THE PRECIP OUT WITH THE NAM AND GFS THE FASTEST.
WILL MAINTAIN LINGERING SHRA MOST OF THE DAY AS PER SURROUNDING
OFFICES GRIDS. WOULDNT BE SURPRISED IF PRECIP ENDS A BIT QUICKER
THAN CURRENTLY ADVERVISED MON PM THOUGH.
FOR MON NGT...ONLY THE EURO HAS LINGERING PRECIP FOR THE CATSKILLS
TO THE UPPER MOHAWK VALLEY. REST OF MODELS ARE BASICALLY DRY. FOR
NOW WILL GO WITH EURO/S AND SURROUNDING OFFICES IDEA OF SLGHT CHC
TO CHC SHRA MON EVE...THEN END PRECIP AFTER MIDNIGHT INTO ERLY
TUESDAY.
FOR TUE... HAVE POP UP SHRA GIVEN THE COLDER AIR ALOFT. TUE NGT
WILL SEE HIGH PRESSURE AND FAIR WEATHER. A FEW LINGERING SHRA
STILL POSSIBLE IN THE FINGER LAKES REGION CLOSER TO THE NEXT WAVE.
&&
.LONG TERM /WEDNESDAY THROUGH SATURDAY/...
145 PM UPDATE...
HIPRES AT THE SFC WL BE OVR THE CWA AT THE START OF THE LONG TERM
PD. HWVR FLOW ALOFT WL BE DOMINATED BY A L/WV TROF. THIS WL KEEP
SLGT CHCS FOR AFTN SHRA/TSRA THRU THE END OF THE WEEK AND GIVE
CREDENCE TO THE WORDS "DIRTY HIGH." HV BASICALLY FOLLOWED WPC
GUIDANCE WITH 20 POPS EACH AFTN ALONG WITH NR NORMAL TEMPS, WITH
HIGHS ARND 80 AND LOWS IN THE 50S EXPECTED EACH PERIOD.
&&
.AVIATION /07Z SUNDAY THROUGH THURSDAY/...
A MID LEVEL SHORT WAVE MOVING THROUGH THE EASTERN GREAT LAKES MAY
PRODUCE MVFR SHOWERS AT KRME/KSYR BETWEEN 08Z-12Z. OTHERWISE
GENERALLY VFR CONDITIONS EARLY THIS MORNING WITH OCCASIONAL MVFR
CIGS AROUND DAYBREAK UNDER INCREASINGLY MOIST SOUTHWEST FLOW. BY
MID MORNING ANY RESTRICTIONS WILL LIFT WITH SCT/BKN CONDITIONS
AROUND 4-5K FT. ISOLATED CONVECTION IS POSSIBLE THIS AFTERNOON BUT
NOT INCLUDED DUE TO VERY LIMITED AREAL COVERAGE. THIS EVENING A
DEEP UPPER LEVEL TROF AND ASSOCIATED SFC LOW WILL BRING WIDESPREAD
MODERATE SHOWERS TO THE TERMINALS. ACROSS THE SOUTHERN TERMINALS
BEGAN THIS ACTIVITY AROUND 00Z AND LEFT OUT OF KSYR/KRME AS IT
WILL BEGIN TOWARD END OFF TAF PERIOD.
S/SW WINDS EARLY THIS MORNING AROUND 5-8 KNOTS EXCEPT SE AT KRME.
AFTER MID MORNING SOUTHWEST WINDS AROUND 10 KNOTS BECOMING LIGHT
AND VARIABLE OVERNIGHT.
OUTLOOK...
MON-MON NGT...POTENTIAL RESTRICTIONS IN SHRA/TSRA.
TUE-THU...RESTRICTIONS POSSIBLE EACH AFTERNOON IN SHRA.
&&
.BGM WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NY...NONE.
&&
$$
SYNOPSIS...DJN
NEAR TERM...DJN
SHORT TERM...DJN
LONG TERM...PVN
AVIATION...RRM
AREA FORECAST DISCUSSION
NWS BURLINGTON VT
214 AM EDT SUN JUL 27 2014
.SYNOPSIS...
AN ACTIVE PERIOD OF WEATHER IS EXPECTED ACROSS THE NORTH COUNTRY
WITH SEVERAL ROUNDS OF SHOWERS WITH EMBEDDED THUNDERSTORMS LIKELY.
FIRST ROUND ARRIVES LATE TONIGHT INTO SUNDAY...WITH ADDITIONAL
SHOWERS ON MONDAY INTO TUESDAY. DAYTIME HIGH TEMPERATURES WILL BE
SLIGHTLY BELOW NORMAL...WITH SLIGHTLY ABOVE NORMAL OVERNIGHT
LOWS...DUE TO CLOUDS. IN ADDITION...AN INCREASE IN THE RELATIVE
HUMIDITY VALUES WILL OCCUR BY SUNDAY AFTERNOON.
&&
.NEAR TERM /UNTIL 6 AM THIS MORNING/...
AS OF 1252 AM EDT SUNDAY...GIVEN INCREASING AREAL COVERAGE OF
SHOWERS PER COMPOSITE RADAR IMAGERY...I`VE ADJUSTED POPS AND WX TO
REFLECT AREAL COVERAGE WORDING. MID-LEVEL SHORTWAVE TROUGH EVIDENT
IN WV IMAGERY ACROSS LAKE HURON PRIMARILY RESPONSIBLE FOR THIS
INCREASE IN AREAL COVERAGE OF SHOWERS NOW ACROSS NORTHERN NEW
YORK. I ALSO NOTE A RATHER SOLID LINE OF HEAVIER SHOWERS AND
EMBEDDED THUNDERSTORMS APPROACHING THE NORTHWESTERN SHORE OF LAKE
ONTARIO - ASSOCIATED WITH A ZONE OF SLIGHTLY NEGATIVE SHOWALTER
INDICES (-1 TO -2) PER 03Z RAP ANALYSES IN ADDITION TO
AFOREMENTIONED MID- LEVEL SHORTWAVE. THOSE NEGATIVE SHOWALTERS ARE
PROGGED TO TRANSLATE EASTWARD...LIKELY KEEPING A THUNDER THREAT
GOING AS IT MOVES EAST EARLY THIS MORNING. HRRR AND WRF-ARW APPEAR
TO HAVE THE BEST HANDLE ON ONGOING ACTIVITY. EXTRAPOLATION OF THE
MORE SOLID LINE OF SHOWERS AND STORMS INTO ST. LAWRENCE VALLEY
NEXT COUPLE HOURS...ADIRONDACKS BY THE PRE- DAWN
HOURS/SUNRISE...AND CHAMPLAIN VALLEY AROUND 6-7 AM. UNTIL
THEN...EXPECT SCATTERED SHOWERS TO GRADUALLY SPREAD EAST. CHANGE
IN WX GRIDS ESSENTIALLY STATES SCATTERED TO NUMEROUS
SHOWERS...WITH SCATTERED T-STORMS TIED TO HIGHEST POP (70-80%).
OTHERWISE...MADE MOSTLY MINOR ADJUSTMENTS TO LOWS ACROSS EAST VT
AND THE ADIRONDACKS.
&&
.SHORT TERM /6 AM THIS MORNING THROUGH MONDAY NIGHT/...
AS OF 335 PM EDT SATURDAY...ACTIVE WEATHER PERIOD ANTICIPATED WITH PERIODS
OF OCCASIONAL SHOWERS WITH SOME EMBEDDED THUNDERSTORMS EXPECTED. FORECAST
FOCUS WILL BE TIMING OF PRECIPITATION AND POTENTIAL FOR A FEW STRONGER
STORMS ON SUNDAY...IF ENOUGH INSTABILITY CAN DEVELOP. ON SUNDAY...1ST
S/W ENERGY AND ASSOCIATED PRECIPITATION WILL EXIT VT BY 15Z. QUESTION
WILL BE HOW MUCH CLEARING DEVELOPS ON SUNDAY AFTERNOON TO CAUSE SURFACE
HEATING AND INCREASE OUR INSTABILITY PARAMETERS. MODELS VARY ON THIS
GREATLY WITH THE LOCAL BTV4 SHOWING CAPE VALUES BETWEEN 1500 AND 1800
J/KG...WHILE NAM12 IS BETWEEN 1000 AND 1200 J/KG AND THE GFS VALUES
RANGE FROM 800 TO 1000 J/KG...WITH ALL MODELS SUGGESTING 0 TO 6 KM
SHEAR VALUES BETWEEN 30 AND 40 KNOTS ON SUNDAY AFTERNOON. THINKING
ENOUGH INSTABILITY WILL DEVELOP TO PROMOTE CONVECTIVE UPDRAFTS
WITH A FEW STRONGER STORMS POSSIBLE. HOWEVER...SYNOPTIC SCALE
FORCING WILL BE MINIMAL AFTER MORNING S/W ENERGY EXITS OUR
AREA...BUT LEFTOVER OUTFLOW BOUNDARIES AND TERRAIN WILL BE FOCUS
FOR AFTERNOON SHOWERS/STORM DEVELOPMENT. WILL MENTION LIKELY POPS
EASTERN/CENTRAL OUR AREA THROUGH 15Z...THEN TAPER TO CHANCE POPS
WITH HIGHEST VALUES ACROSS THE MOUNTAINS. A FEW STRONGER STORMS
WILL BE CAPABLE OF PRODUCING SMALL HAIL AND BRIEF GUSTY
WINDS...BUT AREAL COVERAGE WILL BE LIMITED THEREFORE WILL NOT
MENTION IN GRIDS...BUT WILL IN THE HAZARDOUS WEATHER OUTLOOK.
PROGGED 85H TEMPS BETWEEN 12-14C ON SUNDAY WITH SOME SUN/MIXING
SHOULD SUPPORT AFTERNOON HIGHS IN THE M70S MOUNTAINS/NEK TO
U70S/L80S WARMER VALLEYS.
FOR SUNDAY NIGHT THROUGH MONDAY NIGHT...LARGE SCALE SYNOPTIC PATTERN
SHOWS A DEVELOPING FULL LATITUDE TROF ACROSS THE EASTERN CONUS...WHILE
RIDGE BUILDS ACROSS THE INTER-MOUNTAIN WEST. THIS DEEP TROF WILL RESULT
IN UNSETTLED WEATHER ACROSS OUR OUR AREA...WITH A WIDESPREAD WETTING
RAINFALL EVENT LIKELY ON SUNDAY NIGHT INTO MONDAY. POTENT S/W
ENERGY WILL DIG ACROSS THE CENTRAL GREAT LAKES ON SUNDAY EVENING
AND BE LOCATED OVER SOUTHERN NEW ENGLAND BY 12Z MONDAY...WHILE A
NEGATIVELY TITLED 7/5H TROF DEVELOPS. THIS ENERGY...COMBINED WITH
DEVELOPING NEGATIVELY TILTED MID/UPPER LEVEL TROF AND SURFACE LOW
PRES TRACKING FROM NW PA TO CENTRAL NEW ENGLAND WILL PRODUCE A
MODERATE RAINFALL EVENT ACROSS OUR OUR AREA. THIS SYNOPTIC SETUP
DURING THE WINTER MONTHS WOULD HAVE RESULTED IN A NICE
ACCUMULATING SNOWFALL. LIKE MOST WINTER STORMS...THIS SYSTEM WILL
COME IN 2 PARTS...1ST WILL BE MID LEVEL WAA AND ASSOCIATED
LIFT/MOISTURE BTWN 06Z-12Z MONDAY...WITH BRIEF BREAK...BEFORE WRAP
AROUND MID LEVEL MOISTURE AND DEFORMATION ZONES DEVELOPS ON
BACKSIDE AFT 18Z MONDAY. STILL SOME QUESTION IF INSTABILITY CAN
DEVELOP IN DRY SLOT ON MONDAY...FOR POTENTIAL STORMS. THINKING
PLENTY OF LOW LEVEL MOISTURE AND CLOUDS WILL LIMIT SURFACE
HEATING...ESPECIALLY WITH SURFACE LOW TRACKING TO OUR
SOUTH...PLACING MOST OF OUR OUR AREA ON THE COOL SIDE OF THE
STORM. HAVE NOTED THE 12Z GFS SHOWING SURFACE BASED CAPE BTWN 1500
AND 1800 J/KG ACROSS CENTRAL/EASTERN VT ON MONDAY
AFTERNOON...WHICH COMBINED WITH POSITION OF POTENT 5H VORT AND
AVAILABLE MOISTURE WOULD SUPPORT SOME THUNDERSTORM DEVELOPMENT.
THIS POTENTIAL WILL NEED TO BE WATCHED CAREFULLY ESPECIALLY IF
SURFACE LOW PRES TRACKS FURTHER WEST AND PLACES OUR OUR AREA IN
THE WARM SECTOR ON MONDAY AFTERNOON...WITH GREATER INSTABILITY. A
GENERAL LIGHT TO MODERATE RAIN WILL OCCUR ON MONDAY NIGHT...ASSOCIATED
WITH BACK SIDE DEFORMATION. BOTH GFS/NAM SHOW GOOD RIBBON OF 850
TO 500MB RH WITH SOME ENHANCED 850 TO 700MB UVVS ACROSS THE
CHAMPLAIN VALLEY AND POINTS EAST. QPF WILL RANGE FROM 0.25 TO 0.50
ACROSS THE SAINT LAWRENCE VALLEY TO 0.50 TO 1.50" ACROSS THE
ADIRONDACKS INTO EASTERN VT. NO WIDESPREAD HYDRO ISSUES ARE
ANTICIPATED ATTM. TEMPS WILL BE TRICKY AND HIGHLY DEPEND UPON
AMOUNT OF SUNSHINE ON MONDAY...THINKING MAINLY 60S MOUNTAINS TO
70S VALLEYS WITH LOWS GENERALLY IN THE 50S TO NEAR 60F.
&&
.LONG TERM /TUESDAY THROUGH SATURDAY/...
AS OF 318 PM EDT SATURDAY...HIGHLY AMPLIFIED PATTERN WILL PREVAIL
THROUGH THE EXTENDED PORTION OF THE FORECAST WITH DEEP TROUGH OVER
THE EASTERN THIRD OF THE U.S. WITH A LARGE RIDGE OVER THE WEST.
CHANCES FOR RAIN WILL BE DECREASING TUESDAY MORNING AS SHORTWAVE AND
ASSOCIATED WEAK SURFACE LOW DEPART INTO EASTERN CANADA.
DESPITE THE PRESENCE OF LARGE UPPER TROUGH OVER THE REGION...EXPECT
MUCH OF THE TIME TO BE DRY TUESDAY AFTERNOON THROUGH FRIDAY. ANY
SHORTWAVES MOVING THROUGH THE MEAN TROUGH DIFFICULT TO TIME...AND
WITH LACK OF MOISTURE AND LARGE SCALE FORCING...EXPECT ANY SHOWERS
TO BECOME MORE DIURNALLY DRIVEN...WITH BEST CHANCE DURING THE
AFTERNOON HOURS EACH DAY. HAVE GONE WITH EITHER SLIGHT CHANCE OR
LOW CHANCE POPS MOST DAYS...AND MAINLY DRY FOR THE OVERNIGHT HOURS.
NOT MUCH CHANGE NEXT SATURDAY...ALTHOUGH ECMWF AND GFS DIFFER BY
THIS TIME IN POSITION OF UPPER TROUGH. ECMWF MORE PROGRESSIVE WHILE
GFS HAS TROUGH RETROGRADING. HAVE GONE WITH 20-30 PERCENT CHANCE OF
SHOWERS.
BELOW NORMAL TEMPS EXPECTED THROUGH MIDWEEK. 850 MB TEMPS PROGGED TO
BE NO HIGHER THAN +10C TUE THEN MODERATING SLIGHTLY TO 11-13C WED
THROUGH FRI. WITH PARTIAL SUN...THIS SUPPORTS HIGHS ONLY IN THE 70S
TUE/WED...MODERATING TO AROUND 80 THU/FRI...WITH LITTLE CHANGE
SATURDAY.
&&
.AVIATION /06Z SUNDAY THROUGH THURSDAY/...
THROUGH 06Z MONDAY..TRENDING MVFR EARLY THIS MORNING WITH SHOWERS
ALREADY OVER THE REGION AND WITH THUNDERSTORMS MOVING INTO THE
REGION FROM ONTARIO ASSOCIATED WITH A WEAK WARM FRONT.
CHANCE OF SHOWERS ARE NEAR 80 PERCENT THROUGH ABOUT 15Z TODAY THEN DECREASE.
CHANCES OF THUNDER ARE INCREASING ESPECIALLY FROM SLK TO BTV AND
RUT TO MPV MOVING WEST TO EAST 09-13Z BUT WILL HANDLE WITH
AMENDMENTS AS IT REMAINS TO BE SEEN EXACTLY WHERE THE
THUNDERSTORMS TRACK AND IF THEY HOLD TOGETHER.
VISIBILITIES EXPECTED TO REMAIN MAINLY VFR...EXCEPT SOME BRIEF
REDUCTIONS TO MVFR/IFR POSSIBLE IN ANY HEAVIER SHOWERS OR ISOLATED
THUNDERSTORMS.
CEILINGS WILL GRADUALLY LOWER AND PERIODS OF MVFR ARE LIKELY ON
BACK SIDE OF RAIN SHOWERS...LASTING UNTIL LATE MORNING WHEN SHOWER
THREAT DECREASES. CEILINGS LIFT BACK TO VFR BY SUNDAY AFTERNOON.
SCATTERED SHOWER AND ISOLATED THUNDERSTORM DEVELOPMENT POSSIBLE
AGAIN SUNDAY AFTERNOON/EVENING AHEAD OF A SLOW SOUTHWARD MOVING
COLD FRONT IN CANADA. WILL SHOW WITH VCSH/VCTS FOR NOW AS PROBABILITIES
DROP TO 20-30 PERCENT.
SHOWER AND THUNDER CHANCES DROP THIS EVENING UNDER VFR CONDITIONS.
COULD BE SOME FG/BR CHANCES LATER TONIGHT IF CLEARING SKIES AND
LIGHT WINDS PREVAIL AS FRONTAL SYSTEM STALLS TO OUR NORTH.
LIGHT SOUTH WINDS TONIGHT TURN SOUTH/SOUTHWEST ON SUNDAY FROM 5 TO
10 KNOTS. SOME GUSTS TO 20 KNOTS POSSIBLE.
OUTLOOK 06Z MONDAY THROUGH THURSDAY...
06Z MON - 12Z TUE...PERIODS OF MVFR IN RAIN SHOWERS AND ISOLATED
THUNDERSTORMS. LOCAL IFR POSSIBLE.
12Z TUE - 12Z THU...TRENDING VFR. POSSIBLE IFR/LOWER VISIBILITY IN
OVERNIGHT FOG/MIST MPV AND SLK.
12Z THU ONWARD...MAINLY VFR ALTHOUGH BRIEF PERIODS OF MVFR
POSSIBLE IN SCATTERED SHOWERS...MAINLY SLK/MSS.
&&
.BTV WATCHES/WARNINGS/ADVISORIES...
VT...NONE.
NY...NONE.
&&
$$
SYNOPSIS...TABER
NEAR TERM...EVENSON/LOCONTO
SHORT TERM...TABER
LONG TERM...RJS
AVIATION...SISSON
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
201 AM EDT SUN JUL 27 2014
.SYNOPSIS...
A SERIES OF LOW PRESSURE SYSTEMS WILL TRACK FROM THE MIDWEST TO
THE EAST COAST THROUGH MONDAY BRINGING INCREASINGLY HUMID AIR TO
THE AREA ALONG WITH A GOOD CHANCE OF SHOWERS AND THUNDERSTORMS.
THE BEST CHANCE FOR A WIDESPREAD RAIN LOOKS TO BE SUNDAY NIGHT
INTO MONDAY. COOLER AND DRYER WEATHER WILL FOLLOW BEHIND THESE
SYSTEMS TUESDAY AND WEDNESDAY.
&&
.NEAR TERM /THROUGH TODAY/...
RADARS SHOW SOME SCATTERED RAIN SHOWERS JUST CLIPPING FAR NORTHEAST
ONEIDA COUNTY AT THIS TIME. THESE SHOWERS WERE EXITING NORTH CENTRAL
NEW YORK AS A WEAKENING UPPER LEVEL WAVE CONTINUES TO TRACK EASTWARD
TOWARD NEW ENGLAND. WATER VAPOR IMAGERY SHOWS A MUCH MORE SUBSTANTIAL
SHORT WAVE PRESENTLY OVER LOWER MICHIGAN AND LAKE HURON. THIS
FEATURE WAS CAPTURED WELL IN THE TROPOPAUSE PRESSURE FIELDS FOR THE
1.5 PV UNIT ON THE LATEST RAP MODEL. THIS FEATURE IS PROJECTED TO
TRACK INTO CENTRAL NY BY 12Z. RADAR SHOWS A SWATH OF SHOWERS AND
THUNDERSTORMS OVER ONTARIO WITH MUCH LESS SOUTHWARD. THE HI RES
MESOSCALE MODELS ARE HAVING TROUBLE SIMULATING THE PRESENT RADAR
COVERAGE THUS FEEL THEY LIKELY ARE A BIT SUSPECT. THE HRRR HAS THE
BEST HANDLE SO FAR AND LIKE THE OTHER HI RESOLUTION MODELS BRINGS A
SWATH OF SHOWERS AND THUNDERSTORMS ACRS CENTRAL NY BTWN 9 AND 12Z.
SO AS THIS WAVE PASSES BY LATER THIS MORNING, I WILL HAVE LIKELY
POPS IN NC NY AND TAPER THEM DOWN TO CHC IN NE PA.
AFTER THIS WAVE PASSES AFTER 12Z...CENTRAL NY AND NORTHEAST PA GETS
INTO A LULL WITH MID-LEVEL SUBSIDENCE. MODELS ALL SHOW A NICE
LOW-LEVEL JET FEATURE TRANSPORTING LOW-LEVEL MOISTURE NORTHWARD
DURING THE ERLY MORNING HOURS WITH THE WAVE THAT WILL PASS ACRS C NY
MENTIONED ABV. HENCE DWPTS ABV THE SURFACE WILL BE HIGH ENOUGH TO MIX
DOWN MID TO UPPER 60S DEWPOINTS WITH INSOLATION LATER IN THE MORNING
AND AFTERNOON. SOME LOCALES LIKELY WILL HAVE SFC DEWPOINTS IN THE LOWER 70S.
EVENTUALLY BY AFTERNOON THERE WILL BE ENUF SUNSHINE FOR SIGNIFICANT
INSTABILITY TO DEVELOP. I EXPECT CAPES BETWEEN 1000 AND 2000 J/KG
MIXED LAYER. THE WIND SHEAR INITIALLY THIS AFTERNOON IS FAVORABLE
FOR SEVERE WINDS AND POTENTIAL LARGE HAIL. HOWEVER...THERE IS NO
REAL TRIGGER TO FOCUS ANY CONVECTION THIS AFTERNOON. GIVEN THE
POTENTIAL WE CAN NOT RULE OUT AN ISOLATED TO SCT THUNDERSTORM AND
KEPT POPS IN OUR GRIDS BUT BELIEVE BULK OF ACVTY WILL COME SUNDAY
EVENING AND SUNDAY NIGHT AND NEXT MAJOR WAVE AFFECTS THE REGION.
&&
.SHORT TERM /TONIGHT THROUGH TUESDAY/...
THE WAVE BRINGING TONIGHTS SHOWER AND THUNDERSTORM CHANCES WILL BE
MOVING OFF TO THE EAST OF THE AREA SUNDAY MORNING. LARGE-SCALE
FORCING FOR UPWARD MOTION WILL BE WEAK ON SUNDAY AS THE AREA WILL
RESIDE BETWEEN THIS WAVE AND ANOTHER STRONGER SYSTEM ADVANCING
EAST ACROSS THE OHIO VALLEY. THE ATMOSPHERE WILL BECOME QUITE
UNSTABLE SUNDAY AFTERNOON WITH CAPE VALUES RANGING FROM 1000 TO
2000 J/KG. WITH 30-40 KT MID-LEVEL WINDS EXPECTED ANY SCATTERED
THUNDERSTORMS THAT CAN DEVELOP COULD BECOME SEVERE... BUT AT THIS
TIME WE ARE ONLY EXPECTED ISOLATED TO LOW CHANCE COVERAGE DUE TO
THE LACK OF LARGE SCALE FORCING.
FORCING WILL INCREASE DRAMATICALLY SUNDAY NIGHT INTO MONDAY AS AN
UNSEASONABLY STRONG UPPER LEVEL LOW PRESSURE SYSTEM ADVANCES FROM
THE OHIO VALLEY AND GREAT LAKES TOWARD THE EAST COAST. SOME STORMS
ON THE LEADING EDGE OF THIS SYSTEM COULD BE SEVERE SUNDAY EVENING
WITH SOME LINGERING INSTABILITY LEFT OVER FROM THE AFTERNOON.
LATER SUNDAY NIGHT THE CHANCE FOR HEAVY RAIN WILL INCREASE AS THE
UPPER SYSTEM SWINGS EAST TOWARD THE AREA WITH WIDESPREAD RAIN
POTENTIAL INCREASING.
SURFACE LOW PRESSURE WILL EVENTUALLY DEVELOP NEAR THE NORTHERN
MID-ATLANTIC OR SOUTHERN NEW ENGLAND COAST EARLY MONDAY... THEN
TRACK NORTHEAST ALONG THE COAST MONDAY AFTERNOON. AN AREA OF
STEADY AND POTENTIALLY MODERATE TO HEAVY RAINFALL MAY OCCUR TO THE
NORTHWEST OF THIS SYSTEM IN AN AREA OF MID-LEVEL DEFORMATION
ASSOCIATED WITH THE MID-LEVEL LOW. AT THIS POINT MONDAY LOOKS TO
BE A COOL DAY WITH LOTS OF CLOUD COVER AND SHOWERS WHICH WILL
LIMIT THE INSTABILITY AND THEREFORE THE SEVERE THREAT. RAINFALL
WILL TAPER OFF AND END TOWARD MONDAY EVENING. TUESDAY LOOKS TO BE
A COOL DAY WITH NOTHING MORE THAN SCATTERED LIGHT AFTERNOON
SHOWERS.
&&
.LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/...
145 PM UPDATE...
HIPRES AT THE SFC WL BE OVR THE CWA AT THE START OF THE LONG TERM
PD. HWVR FLOW ALOFT WL BE DOMINATED BY A L/WV TROF. THIS WL KEEP
SLGT CHCS FOR AFTN SHRA/TSRA THRU THE END OF THE WEEK AND GIVE
CREDENCE TO THE WORDS "DIRTY HIGH." HV BASICALLY FOLLOWED WPC
GUIDANCE WITH 20 POPS EACH AFTN ALONG WITH NR NORMAL TEMPS, WITH
HIGHS ARND 80 AND LOWS IN THE 50S EXPECTED EACH PERIOD.
&&
.AVIATION /06Z SUNDAY THROUGH THURSDAY/...
A MID LEVEL SHORT WAVE MOVING THROUGH THE EASTERN GREAT LAKES MAY
PRODUCE MVFR SHOWERS AT KRME/KSYR BETWEEN 08Z-12Z. OTHERWISE
GENERALLY VFR CONDITIONS EARLY THIS MORNING WITH OCCASIONAL MVFR
CIGS AROUND DAYBREAK UNDER INCREASINGLY MOIST SOUTHWEST FLOW. BY
MID MORNING ANY RESTRICTIONS WILL LIFT WITH SCT/BKN CONDITIONS
AROUND 4-5K FT. ISOLATED CONVECTION IS POSSIBLE THIS AFTERNOON BUT
NOT INCLUDED DUE TO VERY LIMITED AREAL COVERAGE. THIS EVENING A
DEEP UPPER LEVEL TROF AND ASSOCIATED SFC LOW WILL BRING WIDESPREAD
MODERATE SHOWERS TO THE TERMINALS. ACROSS THE SOUTHERN TERMINALS
BEGAN THIS ACTIVITY AROUND 00Z AND LEFT OUT OF KSYR/KRME AS IT
WILL BEGIN TOWARD END OFF TAF PERIOD.
S/SW WINDS EARLY THIS MORNING AROUND 5-8 KNOTS EXCEPT SE AT KRME.
AFTER MID MORNING SOUTHWEST WINDS AROUND 10 KNOTS BECOMING LIGHT
AND VARIABLE OVERNIGHT.
OUTLOOK...
MON-MON NGT...POTENTIAL RESTRICTIONS IN SHRA/TSRA.
TUE-THU...RESTRICTIONS POSSIBLE EACH AFTERNOON IN SHRA.
&&
.BGM WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NY...NONE.
&&
$$
SYNOPSIS...DJN
NEAR TERM...DJN
SHORT TERM...MSE
LONG TERM...PVN
AVIATION...RRM
AREA FORECAST DISCUSSION
NWS BURLINGTON VT
1253 AM EDT SUN JUL 27 2014
.SYNOPSIS...
AN ACTIVE PERIOD OF WEATHER IS EXPECTED ACROSS THE NORTH COUNTRY
WITH SEVERAL ROUNDS OF SHOWERS WITH EMBEDDED THUNDERSTORMS LIKELY.
FIRST ROUND ARRIVES LATE TONIGHT INTO SUNDAY...WITH ADDITIONAL
SHOWERS ON MONDAY INTO TUESDAY. DAYTIME HIGH TEMPERATURES WILL BE
SLIGHTLY BELOW NORMAL...WITH SLIGHTLY ABOVE NORMAL OVERNIGHT
LOWS...DUE TO CLOUDS. IN ADDITION...AN INCREASE IN THE RELATIVE
HUMIDITY VALUES WILL OCCUR BY SUNDAY AFTERNOON.
&&
.NEAR TERM /UNTIL 6 AM THIS MORNING/...
AS OF 1252 AM EDT SUNDAY...GIVEN INCREASING AREAL COVERAGE OF
SHOWERS PER COMPOSITE RADAR IMAGERY...I`VE ADJUSTED POPS AND WX TO
REFLECT AREAL COVERAGE WORDING. MID-LEVEL SHORTWAVE TROUGH EVIDENT
IN WV IMAGERY ACROSS LAKE HURON PRIMARILY RESPONSIBLE FOR THIS
INCREASE IN AREAL COVERAGE OF SHOWERS NOW ACROSS NORTHERN NEW
YORK. I ALSO NOTE A RATHER SOLID LINE OF HEAVIER SHOWERS AND
EMBEDDED THUNDERSTORMS APPROACHING THE NORTHWESTERN SHORE OF LAKE
ONTARIO - ASSOCIATED WITH A ZONE OF SLIGHTLY NEGATIVE SHOWALTER
INDICES (-1 TO -2) PER 03Z RAP ANALYSES IN ADDITION TO
AFOREMENTIONED MID- LEVEL SHORTWAVE. THOSE NEGATIVE SHOWALTERS ARE
PROGGED TO TRANSLATE EASTWARD...LIKELY KEEPING A THUNDER THREAT
GOING AS IT MOVES EAST EARLY THIS MORNING. HRRR AND WRF-ARW APPEAR
TO HAVE THE BEST HANDLE ON ONGOING ACTIVITY. EXTRAPOLATION OF THE
MORE SOLID LINE OF SHOWERS AND STORMS INTO ST. LAWRENCE VALLEY
NEXT COUPLE HOURS...ADIRONDACKS BY THE PRE- DAWN
HOURS/SUNRISE...AND CHAMPLAIN VALLEY AROUND 6-7 AM. UNTIL
THEN...EXPECT SCATTERED SHOWERS TO GRADUALLY SPREAD EAST. CHANGE
IN WX GRIDS ESSENTIALLY STATES SCATTERED TO NUMEROUS
SHOWERS...WITH SCATTERED T-STORMS TIED TO HIGHEST POP (70-80%).
OTHERWISE...MADE MOSTLY MINOR ADJUSTMENTS TO LOWS ACROSS EAST VT
AND THE ADIRONDACKS.
&&
.SHORT TERM /6 AM THIS MORNING THROUGH MONDAY NIGHT/...
AS OF 335 PM EDT SATURDAY...ACTIVE WEATHER PERIOD ANTICIPATED WITH PERIODS
OF OCCASIONAL SHOWERS WITH SOME EMBEDDED THUNDERSTORMS EXPECTED. FORECAST
FOCUS WILL BE TIMING OF PRECIPITATION AND POTENTIAL FOR A FEW STRONGER
STORMS ON SUNDAY...IF ENOUGH INSTABILITY CAN DEVELOP. ON SUNDAY...1ST
S/W ENERGY AND ASSOCIATED PRECIPITATION WILL EXIT VT BY 15Z. QUESTION
WILL BE HOW MUCH CLEARING DEVELOPS ON SUNDAY AFTERNOON TO CAUSE SURFACE
HEATING AND INCREASE OUR INSTABILITY PARAMETERS. MODELS VARY ON THIS
GREATLY WITH THE LOCAL BTV4 SHOWING CAPE VALUES BETWEEN 1500 AND 1800
J/KG...WHILE NAM12 IS BETWEEN 1000 AND 1200 J/KG AND THE GFS VALUES
RANGE FROM 800 TO 1000 J/KG...WITH ALL MODELS SUGGESTING 0 TO 6 KM
SHEAR VALUES BETWEEN 30 AND 40 KNOTS ON SUNDAY AFTERNOON. THINKING
ENOUGH INSTABILITY WILL DEVELOP TO PROMOTE CONVECTIVE UPDRAFTS
WITH A FEW STRONGER STORMS POSSIBLE. HOWEVER...SYNOPTIC SCALE
FORCING WILL BE MINIMAL AFTER MORNING S/W ENERGY EXITS OUR
AREA...BUT LEFTOVER OUTFLOW BOUNDARIES AND TERRAIN WILL BE FOCUS
FOR AFTERNOON SHOWERS/STORM DEVELOPMENT. WILL MENTION LIKELY POPS
EASTERN/CENTRAL OUR AREA THROUGH 15Z...THEN TAPER TO CHANCE POPS
WITH HIGHEST VALUES ACROSS THE MOUNTAINS. A FEW STRONGER STORMS
WILL BE CAPABLE OF PRODUCING SMALL HAIL AND BRIEF GUSTY
WINDS...BUT AREAL COVERAGE WILL BE LIMITED THEREFORE WILL NOT
MENTION IN GRIDS...BUT WILL IN THE HAZARDOUS WEATHER OUTLOOK.
PROGGED 85H TEMPS BETWEEN 12-14C ON SUNDAY WITH SOME SUN/MIXING
SHOULD SUPPORT AFTERNOON HIGHS IN THE M70S MOUNTAINS/NEK TO
U70S/L80S WARMER VALLEYS.
FOR SUNDAY NIGHT THROUGH MONDAY NIGHT...LARGE SCALE SYNOPTIC PATTERN
SHOWS A DEVELOPING FULL LATITUDE TROF ACROSS THE EASTERN CONUS...WHILE
RIDGE BUILDS ACROSS THE INTER-MOUNTAIN WEST. THIS DEEP TROF WILL RESULT
IN UNSETTLED WEATHER ACROSS OUR OUR AREA...WITH A WIDESPREAD WETTING
RAINFALL EVENT LIKELY ON SUNDAY NIGHT INTO MONDAY. POTENT S/W
ENERGY WILL DIG ACROSS THE CENTRAL GREAT LAKES ON SUNDAY EVENING
AND BE LOCATED OVER SOUTHERN NEW ENGLAND BY 12Z MONDAY...WHILE A
NEGATIVELY TITLED 7/5H TROF DEVELOPS. THIS ENERGY...COMBINED WITH
DEVELOPING NEGATIVELY TILTED MID/UPPER LEVEL TROF AND SURFACE LOW
PRES TRACKING FROM NW PA TO CENTRAL NEW ENGLAND WILL PRODUCE A
MODERATE RAINFALL EVENT ACROSS OUR OUR AREA. THIS SYNOPTIC SETUP
DURING THE WINTER MONTHS WOULD HAVE RESULTED IN A NICE
ACCUMULATING SNOWFALL. LIKE MOST WINTER STORMS...THIS SYSTEM WILL
COME IN 2 PARTS...1ST WILL BE MID LEVEL WAA AND ASSOCIATED
LIFT/MOISTURE BTWN 06Z-12Z MONDAY...WITH BRIEF BREAK...BEFORE WRAP
AROUND MID LEVEL MOISTURE AND DEFORMATION ZONES DEVELOPS ON
BACKSIDE AFT 18Z MONDAY. STILL SOME QUESTION IF INSTABILITY CAN
DEVELOP IN DRY SLOT ON MONDAY...FOR POTENTIAL STORMS. THINKING
PLENTY OF LOW LEVEL MOISTURE AND CLOUDS WILL LIMIT SURFACE
HEATING...ESPECIALLY WITH SURFACE LOW TRACKING TO OUR
SOUTH...PLACING MOST OF OUR OUR AREA ON THE COOL SIDE OF THE
STORM. HAVE NOTED THE 12Z GFS SHOWING SURFACE BASED CAPE BTWN 1500
AND 1800 J/KG ACROSS CENTRAL/EASTERN VT ON MONDAY
AFTERNOON...WHICH COMBINED WITH POSITION OF POTENT 5H VORT AND
AVAILABLE MOISTURE WOULD SUPPORT SOME THUNDERSTORM DEVELOPMENT.
THIS POTENTIAL WILL NEED TO BE WATCHED CAREFULLY ESPECIALLY IF
SURFACE LOW PRES TRACKS FURTHER WEST AND PLACES OUR OUR AREA IN
THE WARM SECTOR ON MONDAY AFTERNOON...WITH GREATER INSTABILITY. A
GENERAL LIGHT TO MODERATE RAIN WILL OCCUR ON MONDAY NIGHT...ASSOCIATED
WITH BACK SIDE DEFORMATION. BOTH GFS/NAM SHOW GOOD RIBBON OF 850
TO 500MB RH WITH SOME ENHANCED 850 TO 700MB UVVS ACROSS THE
CHAMPLAIN VALLEY AND POINTS EAST. QPF WILL RANGE FROM 0.25 TO 0.50
ACROSS THE SAINT LAWRENCE VALLEY TO 0.50 TO 1.50" ACROSS THE
ADIRONDACKS INTO EASTERN VT. NO WIDESPREAD HYDRO ISSUES ARE
ANTICIPATED ATTM. TEMPS WILL BE TRICKY AND HIGHLY DEPEND UPON
AMOUNT OF SUNSHINE ON MONDAY...THINKING MAINLY 60S MOUNTAINS TO
70S VALLEYS WITH LOWS GENERALLY IN THE 50S TO NEAR 60F.
&&
.LONG TERM /TUESDAY THROUGH SATURDAY/...
AS OF 318 PM EDT SATURDAY...HIGHLY AMPLIFIED PATTERN WILL PREVAIL
THROUGH THE EXTENDED PORTION OF THE FORECAST WITH DEEP TROUGH OVER
THE EASTERN THIRD OF THE U.S. WITH A LARGE RIDGE OVER THE WEST.
CHANCES FOR RAIN WILL BE DECREASING TUESDAY MORNING AS SHORTWAVE AND
ASSOCIATED WEAK SURFACE LOW DEPART INTO EASTERN CANADA.
DESPITE THE PRESENCE OF LARGE UPPER TROUGH OVER THE REGION...EXPECT
MUCH OF THE TIME TO BE DRY TUESDAY AFTERNOON THROUGH FRIDAY. ANY
SHORTWAVES MOVING THROUGH THE MEAN TROUGH DIFFICULT TO TIME...AND
WITH LACK OF MOISTURE AND LARGE SCALE FORCING...EXPECT ANY SHOWERS
TO BECOME MORE DIURNALLY DRIVEN...WITH BEST CHANCE DURING THE
AFTERNOON HOURS EACH DAY. HAVE GONE WITH EITHER SLIGHT CHANCE OR
LOW CHANCE POPS MOST DAYS...AND MAINLY DRY FOR THE OVERNIGHT HOURS.
NOT MUCH CHANGE NEXT SATURDAY...ALTHOUGH ECMWF AND GFS DIFFER BY
THIS TIME IN POSITION OF UPPER TROUGH. ECMWF MORE PROGRESSIVE WHILE
GFS HAS TROUGH RETROGRADING. HAVE GONE WITH 20-30 PERCENT CHANCE OF
SHOWERS.
BELOW NORMAL TEMPS EXPECTED THROUGH MIDWEEK. 850 MB TEMPS PROGGED TO
BE NO HIGHER THAN +10C TUE THEN MODERATING SLIGHTLY TO 11-13C WED
THROUGH FRI. WITH PARTIAL SUN...THIS SUPPORTS HIGHS ONLY IN THE 70S
TUE/WED...MODERATING TO AROUND 80 THU/FRI...WITH LITTLE CHANGE
SATURDAY.
&&
.AVIATION /06Z SUNDAY THROUGH THURSDAY/...
THROUGH 00Z MONDAY...MAINLY VFR THIS EVENING WILL TREND TO
VFR/MVFR LATE TONIGHT AND EARLY SUNDAY MORNING BEFORE IMPROVING
AGAIN TO VFR BY SUNDAY AFTERNOON. VFR EXPECTED UNDER INCREASING
CLOUDS AND DRY WEATHER THROUGH AT LEAST 04Z TONIGHT FOR ALL TAF
SITES. CHANCES FOR RAIN SHOWERS INCREASE AFTER 04Z AT
MSS/SLK...AND 07Z ELSEWHERE. VISIBILITIES EXPECTED TO REMAIN
MAINLY VFR...EXCEPT SOME BRIEF REDUCTIONS TO MVFR/IFR POSSIBLE IN
ANY HEAVIER SHOWERS OR ISOLATED THUNDERSTORMS. CEILINGS WILL
GRADUALLY LOWER AND PERIODS OF MVFR ARE LIKELY ON BACK SIDE OF
RAIN SHOWERS...LASTING INTO SUNDAY MORNING. CEILINGS LIFT BACK TO
VFR BY MIDDAY SUNDAY. ADDITIONAL SHOWER AND THUNDERSTORM
DEVELOPMENT POSSIBLE SUNDAY AFTERNOON/EVENING. WILL SHOW WITH VCSH
FOR NOW. LIGHT SOUTH WINDS TONIGHT TURN SOUTH/SOUTHWEST ON SUNDAY FROM 5
TO 10 KNOTS. SOME GUSTS TO 20 KNOTS POSSIBLE AT KBTV FOR FIRST
HALF OF SUNDAY.
OUTLOOK 00Z MONDAY THROUGH THURSDAY...
00Z MON - 06Z MON...MOSTLY VFR. BRIEF PERIODS MVFR/IFR VISIBILITY IN
SCT SHOWERS/STORMS.
06Z MON - 12Z TUE...PERIODS OF MVFR IN RAIN SHOWERS AND ISOLATED
THUNDERSTORMS.
12Z TUE - 12Z THU...TRENDING VFR. POSSIBLE IFR/LOWER VISIBILITY IN
OVERNIGHT FOG/MIST MPV AND SLK.
12Z THU ONWARD...MAINLY VFR ALTHOUGH BRIEF PERIODS OF MVFR
POSSIBLE IN SCATTERED SHOWERS...MAINLY SLK/MSS.
&&
.BTV WATCHES/WARNINGS/ADVISORIES...
VT...NONE.
NY...NONE.
&&
$$
SYNOPSIS...TABER
NEAR TERM...EVENSON/LOCONTO
SHORT TERM...TABER
LONG TERM...RJS
AVIATION...RJS/MUCCILLI
AREA FORECAST DISCUSSION
NWS BISMARCK ND
309 AM CDT SUN JUL 27 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 308 AM CDT SUN JUL 27 2014
LATEST WATER VAPOR IMAGERY SHOWS AN UPPER CLOSED LOW OVER NORTHERN
MINNESOTA WITH A COMPENSATING NORTHERLY TO NORTHWESTERLY FLOW INTO
NORTH DAKOTA. FOG/STRATUS LOOP AND SURFACE OBSERVATIONS SHOW SEVERAL
POCKETS OF BKN/OVC LOW CLOUDS CONTINUING TO MOVE FROM NORTHERN
NORTH DAKOTA INTO CENTRAL NORTH DAKOTA. PER HRRR CEILING
FORECAST...EXPECT THESE CLOUDS TO LINGER THROUGH MID MORNING THEN
LIFT INTO A FAIRLY LARGE SCT/BKN STRATOCUMULUS FIELD THROUGH THE
AFTERNOON. ENOUGH INSTABILITY WILL EXIST OVER THE FAR SOUTHERN
JAMES RIVER VALLEY/EASTERN LAMOURE AND DICKEY COUNTIES PER
GFS/ECMWF FOR AN ISOLATED AFTERNOON SHOWER OR THUNDERSHOWER. THE
REST OF WESTERN AND CENTRAL NORTH DAKOTA WILL BE DRY. 850MB TEMPS
GENERALLY THE SAME OR 1C COOLER OVER SATURDAYS. WITH CLOUDS
LINGERING MORE ACROSS THE NORTH AND EAST...HIGH TEMPERATURES WILL
ONLY REACH THE LOWER 70S. EXPECT HIGHS IN THE MID/UPPER 70S WEST
THROUGH SOUTH CENTRAL. FOR SUNDAY NIGHT...A SURFACE HIGH PRESSURE
WILL SPREAD ACROSS NORTH CENTRAL NORTH DAKOTA WITH A CLEAR SKY AND
COOL TEMPERATURES. OVERNIGHT LOWS WILL BE AROUND 50F.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 308 AM CDT SUN JUL 27 2014
THE MAIN FEATURE IN THE EXTENDED PERIOD WILL BE A BLOCKING
WEATHER PATTERN FEATURING A LONG WAVE TROUGH OVER THE EASTERN US
AND A RIDGE OVER THE WEST. THIS WILL LEAVE THE NORTHERN PLAINS
GENERALLY CUTOFF FROM GULF MOISTURE AND POPS THROUGH THE PERIOD ARE
LOW. ALTHOUGH NORTHWEST FLOW CAN OFTEN BRING SURPRISE CONVECTION AS
WEAK IMPULSES ARE INEVITABLE EMBEDDED IN THE NORTHWEST FLOW FOR
NOW WILL LEAVE THIS PERIOD DRY. FOR TEMPERATURES EXPECT A GRADUAL
MODERATING TREND FROM BELOW NORMAL TEMPERATURES MONDAY TO NEAR OR
ABOVE NORMAL BY THE WEEKEND.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT)
ISSUED AT 308 AM CDT SUN JUL 27 2014
SCT/BKN LOW VFR/MVFR CIGS AT THE TERMINALS WILL CONTINUE THROUGH
15Z SUNDAY...THEN TREND TOWARD AN ALL SCT/BKN LOW VFR BY
AFTERNOON. EXPECT SKC SUNDAY EVENING/NIGHT. NORTHERLY WINDS WILL
BE LIGHT TODAY RANGING BETWEEN 10 AND 15KT.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...KS
LONG TERM...WAA
AVIATION...KS
AREA FORECAST DISCUSSION
NWS GRAND FORKS ND
246 AM CDT SUN JUL 27 2014
.SHORT TERM...(TODAY THROUGH MONDAY)
ISSUED AT 246 AM CDT SUN JUL 27 2014
HOW MUCH PRECIP HANGS AROUND AS THE UPPER LOW MOVES OFF TO THE
EAST WILL BE THE MAIN FORECAST QUESTION FOR THE PERIOD.
SCATTERED SHOWERS CONTINUE FROM THE RED RIVER VALLEY EASTWARD AS
THE UPPER LOW SLOWLY MOVES SOUTHEASTWARD INTO NORTHERN MINNESOTA.
THE UPPER LOW WILL CONTINUE OFF INTO WI DURING THE DAY...WITH THE
SFC LOW ALSO HEADING OFF AND HIGH PRESSURE BUILDING INTO THE
REGION. THE BEST LIFT WITH THE UPPER LOW WILL EXIT THE AREA FAIRLY
EARLY IN THE DAY. HOWEVER...CONVECTIVE TEMPS REMAIN IN THE UPPER
60S TO LOW 70S...SO SOME REDEVELOPMENT IS NOT OUT OF THE QUESTION
AND THE HRRR SEEMS TO SHOW THIS TREND. THUS...CONTINUED TO KEEP
LOW POPS GOING THROUGH 00Z. TEMPS WILL BE MOSTLY IN THE LOW 70S
WITH NORTH WINDS LESS BREEZY THAN YESTERDAY.
NORTHWESTERLY FLOW ALOFT SETS UP FOR TONIGHT AND CONTINUES INTO
MONDAY. SFC HIGH PRESSURE WILL REMAIN OVER THE NORTHERN PLAINS AND
BRING LIGHT NORTH WINDS. THE NAM WAS SHOWING SOME SIGNS OF A WEAK
SHORTWAVE IN THE NORTHWESTERLY FLOW APPROACHING THE LAKE OF THE
WOODS AREA AND BRINGING SOME ADDITIONAL PRECIP. HOWEVER...IT SEEMS
TO BE AN OUTLIER SO WILL KEEP IT DRY FOR NOW. LOWS TONIGHT SHOULD
DROP QUITE NICELY TO THE LOW 50S UNDER THE SFC HIGH...WITH
AFTERNOON TEMPS ON MONDAY GETTING INTO THE 70S.
.LONG TERM...(MONDAY NIGHT THROUGH SATURDAY)
ISSUED AT 246 AM CDT SUN JUL 27 2014
MONDAY NIGHT THROUGH TUESDAY NIGHT...NORTHWESTERLY FLOW ALOFT AND
SFC HIGH PRESSURE CONTINUE. WITH NOTHING TO FORCE THUNDERSTORM
DEVELOPMENT AND NOT EVEN ANY REAL RETURN FLOW...EXPECT US TO
REMAIN DRY THROUGH THE EARLY PART OF THE WORK WEEK. TEMPS WILL
CONTINUE TO BE SLIGHTLY BELOW SEASONAL AVERAGES ALTHOUGH THEY
SHOULD SLOWLY WARM.
WEDNESDAY-SATURDAY...MAINLY DRY CONDITIONS WITH SEASONABLE TEMPS AND
LIGHT WINDS WILL CONTINUE INTO NEXT WEEKEND...AS THE EASTERN US
TROUGH/WESTERN US RIDGE KEEPS THE NORTHERN PLAINS REGION IN A VERY
QUIET NORTHWEST FLOW PATTERN. ANY PRECIP CHANCES WITH WEAK WAVES
DROPPING OUT OF CANADA ARE TOO LOW TO MENTION RIGHT NOW. TEMPS WILL
SLOWLY WARM THROUGH LATE WEEK.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT)
ISSUED AT 1125 PM CDT SAT JUL 26 2014
SOME SCATTERED MVFR CIGS SHOULD MOVE INTO THE REGION
OVERNIGHT...AND PERSIST INTO SUNDAY MORNING. CONDITIONS SHOULD
RISE INTO THE VFR RANGE IN ALL BUT THE FAR EAST SUNDAY AFTERNOON.
NORTHERLY WINDS COULD GUST TO AROUND 30KT THROUGH SUNDAY MORNING.
&&
.FGF WATCHES/WARNINGS/ADVISORIES...
ND...NONE.
MN...NONE.
&&
$$
SHORT TERM...JR
LONG TERM...JR/MAKOWSKI
AVIATION...DK
AREA FORECAST DISCUSSION
NWS PORTLAND OR
917 PM PDT SAT JUL 26 2014
.SYNOPSIS...AN UPPER LEVEL RIDGE WILL CONTINUE TO BUILD INLAND OVER
THE PACIFIC NORTHWEST SUNDAY AND REMAIN NEAR THE FORECAST AREA
THROUGH MUCH OF NEXT WEEK. THIS WILL BRING WARM AND DRY WEATHER TO
SOUTHWEST WASHINGTON AND NORTHWEST OREGON...EXCEPT FOR A SLIGHT
CHANCE FOR THUNDERSTORMS IN THE CASCADES NEAR THE CREST BEGINNING
SUNDAY AFTERNOON AND EVENING AS A FEW WEAK DISTURBANCES LIFT
NORTHEAST THROUGH THE REGION THROUGH THE UPCOMING WEEK. THE MARINE
LAYER WILL BECOME MORE CONFINED TO THE COAST.
&&
.UPDATE...MINIMAL CHANGES TO THE FORECAST PACKAGE THIS EVENING. MAIN
ITEMS WERE TO MAKE SUBTLE ADJUSTMENTS TO THE LOWS TONIGHT BASED ON
WHERE DEW POINTS SEEM TO BE RUNNING A BIT HIGHER THAN FORECAST.
GIVEN CLEAR SKIES AND RELATIVELY LIGHT WINDS...FELT A DEW POINT
FORECAST WAS BETTER SUITED TO BASE TEMPERATURES FROM. IN
ALL...EXPECT MOST AREAS WILL SEE LOWS AT LEAST THE SAME OR A BIT
HIGHER THAN LAST NIGHT. ALSO REMOVED JUST ABOUT ALL CLOUDS EXCEPT
ALONG THE IMMEDIATE COAST WHERE SOME PATCHY STRATUS COULD REMAIN.
THE HRRR CONDENSATION PRESSURE DEFICIT DATA APPEARS TO BE OVERDOING
THE CURRENT EXTENT OF CLOUD COVER WITH THE NAM HAVING A MUCH BETTER
HANDLE ON THE CURRENT REALITY. WILL LEAN HEAVILY ON THE NAM FOR
OVERNIGHT THROUGH EARLY TOMORROW AFTERNOON. ALSO FEEL THAT PATCHY
GROUND FOG WILL DEVELOP IN LOCALIZED DRAINAGES...SUCH AS THE
TILLAMOOK VALLEY. THAT SHOULD BURN OFF RATHER QUICKLY AFTER SUNRISE.
FOR TOMORROW...MADE SOME BASIC ADJUSTMENTS TO TEMPERATURES GIVEN AN
OVERALL LACK OF CLOUD COVER. DON`T EXPECT DAYTIME HIGHS TO BE ANY
COLDER THAN TODAY TO MADE ADJUSTMENTS TO THE GRIDDED FORECAST TO
ENSURE THAT`S THE CASE. FINALLY...MID LEVEL MOISTURE HAS REMAINED
FURTHER SOUTH THAN MODELS INDICATED IT WOULD. DECIDED TO TRIM THE
ONSET OF THUNDERSTORMS UNTIL LATE AFTERNOON AND REALLY WOULD NOT BE
SURPRISED IF IT WAS AROUND THE 5 TO 6 PM TIME FRAME BEFORE THEY
INITIATE OVER THE CENTRAL OREGON CASCADE WEST SLOPES. WITH HOTTER
TEMPERATURES EAST OF THE CREST...SHOULD SEE A SLIGHTLY EARLIER START
SAY AFTER 2 PM WITH AN OUTSIDE CHANCE ONE COULD DRIFT OVER TO THE
WEST SIDE BEFORE 5 PM. UPDATES AVAILABLE SHORTLY. /JBONK
&&
.PREV DISC... /ISSUED 206 PM PDT SAT JUL 26 2014/
SHORT TERM...SKIES WERE CLEAR THIS AFTERNOON ACROSS SOUTHWEST
WASHINGTON AND NORTHWEST OREGON...AND SHOULD REMAIN SO THROUGH AT
LEAST THE EVENING. TEMPS INLAND STILL LOOK ON TRACK PUSH INTO THE
MID 80S IN MUCH OF THE AREA. TEMPS AT THE COAST ARE TRYING TO CRACK
70.
THE CURRENT PATTERN OF A CLOSED LOW OFF THE B.C. COAST AND AN UPPER
RIDGE INLAND OVER THE WESTERN U.S. WILL CONTINUE THROUGH THE
REMAINDER OF THE WEEKEND AND PRETTY MUCH ALL OF NEXT WEEK. THUS
SUNDAY AND MONDAY WILL BE SIMILAR TO TODAY EXCEPT WARMER. EXPECT
TEMPS TO WARM UP TO AROUND 90 BOTH DAYS...AND POSSIBLY ABOVE 90 BY
MONDAY. MORNING LOW CLOUDS WILL MAINLY BE NEAR THE SOUTH WASHINGTON
AND FAR NORTH OREGON COASTS...BUT MAY NOT BE REALLY SOLID. EVEN THE
COAST WILL SEE SOME NICE TEMPS CLOSE TO 70 BOTH DAYS...WITH PLENTY OF
SUNSHINE AFTER THE BRIEF MORNING LOW CLOUDS. TUESDAY WILL BE SIMILAR
TO MONDAY...EXCEPT PERHAPS A BIT MORE MORNING LOW CLOUDS ALONG THE
COAST.
THERE IS AN UPPER LEVEL DISTURBANCE LIFTING NORTHEAST FROM ALONG THE
CALIFORNIA COAST UP INTO CENTRAL AND EASTERN OREGON SUNDAY AND SUNDAY
EVENING...THAT WILL GIVE OUR OREGON CASCADE CREST AREA A SLIGHT
CHANCE OF THUNDERSTORMS AT THAT TIME. THERE STILL LOOKS LIKE A LITTLE
MOISTURE STILL BRUSHING EASTERN LANE COUNTY MONDAY AFTERNOON AND
EVENING AS WELL BUT THERE IS LESS OF A TRIGGER ON MONDAY. THESE
THUNDERSTORMS BOTH DAYS WILL TEND TO BE OF THE HIGH BASED DRIER
VARIETY. THE POSSIBILITY REMAINS OF AN ISOLATED THUNDERSTORM NEAR THE
CASCADE CREST IN OREGON AGAIN TUESDAY AFTERNOON AND EVENING. TOLLESON
LONG TERM...TUESDAY NIGHT THROUGH SATURDAY. THE PATTERN IN THE SHORT
TERM WILL CONTINUE THROUGH THE LONG TERM PERIOD...WITH AN UPPER LOW
IN THE NORTHEAST PACIFIC OFF THE B.C. COAST AND AN UPPER RIDGE
INLAND OVER THE WESTERN U.S. THIS PUTS SOUTHWEST WASHINGTON AND
NORTHWEST OREGON UNDER SOUTH TO SOUTHWEST FLOW ALOFT. THE MAIN
SUBTLE DIFFERENCE IN THE LONG TERM PERIOD VERSUS THE SHORT TERM
PERIOD IS THAT THE UPPER FLOW MAY TURN A BIT MORE SOUTHERLY AND
ALLOW THUNDERSTORMS TO AFFECT A GREATER PORTION OF THE CASCADES AND
POSSIBLY THE FOOTHILL AREAS...AS WELL AS POSSIBLY SPREAD UP INTO THE
SOUTH WASHINGTON CASCADES AND FOOTHILLS. PRECIPITABLE WATER VALUES
ARE FORECAST TO BEGIN EXCEEDING AN INCH IN THE LONG TERM PERIOD...
BUT THE THUNDERSTORMS WILL STILL TEND TO BE ON THE DRY SIDE AT LEAST
AT FIRST. OTHERWISE...THE AIR MASS REMAINS VERY WARM ACROSS THE AREA
THROUGH THE LONG TERM PERIOD WITH TEMPS REMAINING ABOVE NORMAL AND
UP AROUND 90. WE MAY EVENTUALLY SEE SOME MARINE SEEPAGE THROUGH
COASTAL GAPS DURING THE LATTER PART OF NEXT WEEK...BUT IT WILL TAKE
SOME TIME FOR MUCH COOLING TO ARRIVE INLAND. TOLLESON
&&
.AVIATION...HIGH PRESSURE AND A DRIER LOWER ATMOSPHERE WILL LEAD TO
PREDOMINANTLY VFR CONDITIONS AT ALL TAF SITES THROUGH 06Z MONDAY. GUSTY
NORTH-NORTHWEST WINDS WILL ONCE AGAIN PICK UP ALONG THE COAST AROUND
18Z SUNDAY.
KPDX AND APPROACHES...HIGH PRESSURE AND A RELATIVELY DRY LOWER
ATMOSPHERE WILL LEAD TO VFR CONDITIONS THROUGH 06Z MONDAY. /NEUMAN
&&
.MARINE...HIGH PRESSURE OVER THE NORTHEAST PACIFIC AND THERMAL LOW PRESSURE
OVER NORTHERN CALIFORNIA WILL CONTINUE INTO THE UPCOMING WORK WEEK...LEADING
TO LITTLE CHANGE IN MARINE WEATHER. IN OTHER WORDS...EXPECT PERIODS
OF GUSTY 20 TO 30 KT NORTH WINDS WITH SEAS OCCASIONALLY INCREASING TO
7 FT AND BECOMING STEEP AND SQUARE...ESPECIALLY ACROSS THE CENTRAL OREGON
WATERS. /NEUMAN
&&
.PQR WATCHES/WARNINGS/ADVISORIES...
OR...NONE.
WA...NONE.
PZ...SMALL CRAFT ADVISORY FOR WINDS FROM 3 PM SUNDAY TO 3 AM PDT
MONDAY FOR COASTAL WATERS FROM CAPE SHOALWATER WA TO CASCADE HEAD OR OUT
60 NM.
SMALL CRAFT ADVISORY FOR WINDS UNTIL 3 AM PDT MONDAY FOR COASTAL WATERS
FROM CASCADE HEAD OR TO FLORENCE OR OUT 60 NM.
SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS FROM 3 PM SUNDAY TO 3 AM
PDT MONDAY FOR COASTAL WATERS FROM CASCADE HEAD OR TO FLORENCE OR OUT 60
NM.
&&
$$
MORE WEATHER INFORMATION ONLINE AT...HTTP://WEATHER.GOV/PORTLAND
INTERACT WITH US VIA SOCIAL MEDIA
WWW.FACEBOOK.COM/US.NATIONALWEATHERSERVICE.PORTLAND.GOV
WWW.TWITTER.COM/NWSPORTLAND
THIS DISCUSSION IS FOR NORTHWEST OREGON AND SOUTHWEST WASHINGTON
FROM THE CASCADE CREST TO 60 NAUTICAL MILES OFFSHORE. THE AREA IS
COMMONLY REFERRED TO AS THE FORECAST AREA.
AREA FORECAST DISCUSSION
NWS MILWAUKEE/SULLIVAN WI
313 AM CDT SUN JUL 27 2014
.TODAY AND TONIGHT...FORECAST CONFIDENCE IS HIGH.
A SURFACE COLD FRONT WILL PUSH ACROSS THE FORECAST AREA THIS
MORNING...REACHING MADISON BY 14Z AND MILWAUKEE BETWEEN 16-17Z. WE
COULD SEE A LINE OF SHOWERS AND STORMS DEVELOP ALONG THE FRONT
OVER THE CWA BEFORE IT EXITS TO THE EAST. HEIGHTS ARE FALLING AS
AN IMPRESSIVELY STRONG UPPER TROF DROPS SOUTH INTO THE WESTERN
GREAT LAKES. UP UNTIL NOW...THE COLUMN HAS BEEN FAIRLY DRY IN THE
MID LEVELS OVER SOUTHERN WI WITH DECENT CAPPING IN THE LOW
LEVELS...LIMITING CONVECTIVE DEVELOPMENT. BUT THIS WILL BE
MOISTENING UP QUICKLY JUST AS TEMPS ALOFT ARE COOLING.
THE HRRR SHOWS CONVECTION DEVELOPING ALONG THE FRONT JUST AS IT/S
GETTING TO MADISON. THIS ISN/T A SURE THING...BUT IT LOOKS LIKE A
REASONABLE AND POSSIBLE SCENARIO. BEHIND THE FRONT...THE COLD CORE
UPPER SYSTEM DROPS IN AND PRECIP SHOULD EXPAND UNDER THIS LOW BY
EARLY TO MID AFTERNOON...ESPECIALLY OVER THE NORTHEAST CWA. THIS
WILL BE MAINLY SHOWERS...BUT WE COULD CRACK SOME THUNDER...SO WILL
KEEP THAT MENTION.
DRIER WEATHER WORKS IN QUICKLY TONIGHT IN THE WAKE OF A SECONDARY
COLD FRONT THAT CLEARS SOUTHERN WISCONSIN BY ABOUT 03Z SUN. THIS
WILL BRING CLEARING SKIES WITH TEMPS FALLING INTO THE 50S.
.SHORT TERM...MONDAY THROUGH TUESDAY NIGHT...FORECAST CONFIDENCE
IS MEDIUM.
SHORT TERM MODELS SHOWING 500 MB TROUGH LINGERING OVER
SOUTHEASTERN CANADA INTO THE EASTERN USA DURING THIS PERIOD. THE
UPPER MIDWEST SHOULD REMAIN IN NORTHWESTERLY FLOW AS A RESULT.
WEAK 500 MB VORTICITY MAXIMA PASS THROUGH THE AREA...MAINLY
TUESDAY INTO TUESDAY NIGHT. MODELS ARE SHOWING LIGHT QPF ACROSS
PORTIONS OF THE AREA DURING THIS TIME.
AREA FORECAST SOUNDINGS SHOW ENOUGH SHALLOW MEAN LAYER CAPE FOR
SHOWERS AND A FEW THUNDERSTORMS TUESDAY INTO TUESDAY NIGHT.
CONTINUED POPS FOR TUESDAY AND TUESDAY NIGHT...WITH MONDAY AND
MONDAY NIGHT DRY.
TEMPERATURES WILL BE BELOW SEASONAL NORMALS MONDAY...WITH 925 MB
TEMPERATURES SUPPORTING LOWER 70S EAST TO MID 70S WEST. COOL NIGHT
MONDAY NIGHT WITH LOWS IN THE LOWER TO MID 50S ARE EXPECTED...WITH
MID TO UPPER 70S ON TUESDAY.
.LONG TERM...WEDNESDAY THROUGH SATURDAY...FORECAST CONFIDENCE IS
MEDIUM.
ECMWF/GFS CONTINUE TO SHOW 500 MB TROUGH LINGERING TO THE EAST OF
THE REGION THROUGH THURSDAY NIGHT...WITH ANOTHER TROUGH ROTATING
INTO THE AREA FRIDAY INTO SATURDAY. VARIOUS VORTICITY MAXIMA
SHOULD CONTINUE TO ROTATE THROUGH THE REGION AT TIMES.
GFS FORECAST SOUNDINGS SHOW SOME WEAK INSTABILITY EACH AFTERNOON
AND EVENING DURING THIS PERIOD...WHICH MAY ALLOW FOR SHOWERS AND A
FEW STORMS. KEPT POPS GOING FOR MOST OF THIS PERIOD...GIVEN SOME
UNCERTAINTY WITH THE EXACT TIMING OF PRECIPITATION. TEMPERATURES
SHOULD BE PLEASANT DURING THIS TIME...WITH ONSHORE WINDS AT TIMES
NEAR LAKE MICHIGAN KEEPING THINGS COOLER THERE.
&&
.AVIATION/12Z TAFS/...
LOOK FOR RAPIDLY CHANGING CONDITIONS THROUGH THE TAF PERIOD. WE
START OUT WITH SOME AREAS OF FOG AND POSSIBLE IFR/MVFR
CONDITIONS...BUT THIS WILL ONLY BE A THREAT THROUGH ABOUT 15Z THIS
MORNING. THEREAFTER WINDS INCREASE AHEAD OF AN APPROACHING COLD
FRONT AND THIS SHOULD MIX OUT ANY FOG/LOW CLOUDS.
THE COLD FRONT WILL REACH KMSN BY 14Z AND KMKE/KENW/KUES BTWN
16-17Z. THERE IS A THREAT OF SHOWERS AND STORMS ALONG AND AHEAD OF
THE FRONT...BUT CONDITIONS SHOULD REMAIN AT VFR LEVELS. BEHIND THE
FRONT...COOLER UPPER LEVELS WITH THE ARRIVAL OF A STRONG MID LEVEL
SHORT WAVE WILL RESULT IN EXPANDING PRECIPITATION BY EARLY
AFTERNOON. THIS WILL BE MOSTLY SHOWERS...BUT A THUNDERSTORM IS
POSSIBLE. STILL MAINLY VFR CONDITIONS EXPECTED.
A SECONDARY COLD FRONT WILL PUSH THROUGH THE AREA VERY LATE THIS
AFTERNOON OR EARLY THIS EVENING. THERE COULD BE A PERIOD OF MVFR
CIGS WITH THAT...BUT SKIES WILL CLEAR FROM NORTH TO SOUTH BY 06Z
MONDAY WITH DRIER AND COOLER WEATHER EXPECTED. LOOK FOR MAINLY VFR
CONDITIONS AFTER 06Z MON.
&&
.MARINE...
INCREASING NORTHERLY WINDS TO 15 TO 25 KNOTS BY THIS EVENING...IN
THE WAKE OF A PASSING COLD FRONT...WILL BRING SMALL CRAFT ADVISORY
CONDITIONS FROM ABOUT 4 PM THIS AFTERNOON INTO THE EARLY EVENING
ON SUNDAY. WAVES WILL BUILD TO 4 TO 7 FEET TONIGHT...DIMINISHING
SLOWLY ON SUNDAY.
&&
.BEACHES...
INCREASING NORTH WINDS WILL BRING BUILDING WAVES TO THE BEACHES
FROM SHEBOYGAN SOUTH THROUGH KENOSHA COUNTY. WAVES WILL REACH 3 TO
4 FEET ALONG THE SHORELINE BY EARLY THIS EVENING...BUILDING TO 4
TO 7 FEET TONIGHT...THEN DIMINISHING SLOWLY THROUGH THE AFTERNOON
INTO THE EARLY EVENING ON SUNDAY. A BEACH HAZARDS STATEMENT IS IN
EFFECT FROM THIS EVENING THROUGH MONDAY EVENING.
&&
.MKX WATCHES/WARNINGS/ADVISORIES...
WI...BEACH HAZARDS STATEMENT FROM THIS EVENING THROUGH MONDAY EVENING
FOR WIZ052-060-066-071-072.
LM...SMALL CRAFT ADVISORY FROM 4 PM THIS AFTERNOON TO 7 PM CDT MONDAY
FOR LMZ645-646.
SMALL CRAFT ADVISORY FROM 7 PM THIS EVENING TO 4 PM CDT MONDAY
FOR LMZ643-644.
&&
$$
TODAY/TONIGHT AND AVIATION/MARINE...DAVIS
MONDAY THROUGH SATURDAY...WOOD
AREA FORECAST DISCUSSION
NWS TUCSON AZ
415 AM MST SUN JUL 27 2014
.SYNOPSIS...EXPECT SCATTERED MAINLY AFTERNOON AND EVENING
THUNDERSTORMS THIS WEEK. SOME STORMS WILL GENERATE LOCALLY HEAVY
RAIN AND STRONG GUSTY WINDS.
&&
.DISCUSSION...KEMX WSR-88D DETECTED NUMEROUS 35-55 DBZ ECHOES ACROSS
WRN/CENTRAL PIMA COUNTY VALID 1110Z. ISOLATED MOSTLY LESS THAN 45
DBZ ECHOES WERE OCCURRING FROM TUCSON EWD/SWD TO THE NEW MEXICO/
INTERNATIONAL BORDERS. IR SATELLITE IMAGERY INDICATED MCS EXTENDING
FROM SOUTH CENTRAL AZ SEWD INTO NRN SONORA. VARIOUS RUC HRRR
SOLUTIONS HAVE BEEN VERY CONSISTENT WITH DEPICTING PRECIP TO
CONTINUE UNTIL AROUND MID-MORNING WEST OF TUCSON AS A MCV MOVES NWWD
ACROSS NWRN SONORA. MEANWHILE...THE ISOLATED SHOWERS/TSTMS ONGOING
FROM TUCSON EWD/SWD HAVE NOT BEEN WELL HANDLED BY THE RUC HRRR...
THAT HAD BEEN VERY CONSISTENT WITH DEPICTING PRECIP-FREE CONDITIONS
TO OCCUR THRU LATE THIS MORNING.
SUN-MON...
UPPER RIDGE IS PROGGED TO AMPLIFY OVER THE WRN CONUS. AMPLE MOISTURE
WILL BE AVAILABLE TO SUPPORT SCATTERED SHOWERS/TSTMS...WITH THE BULK
OF THE ACTIVITY TO OCCUR DURING THE AFTERNOON/EVENING HOURS.
ALTHOUGH NO TWO DAYS ARE EXACTLY IDENTICAL DURING THE MONSOON...FROM
A NWP MODEL PERSPECTIVE...THERE APPEAR TO BE SIMILARITIES WITH
SHOWERS/TSTMS THAT OCCURRED SAT AND SAT NIGHT AND WHAT IS PROGGED TO
OCCUR SUN-MON. FOR INSTANCE...IF CLEARING IS SUFFICIENT ACROSS ERN
SECTIONS DURING THE MORNING HOURS...THEN SHOWER/TSTM INITIATION
SHOULD OCCUR EAST-TO-SOUTH OF TUCSON BY EARLY AFTERNOON. THIS
ACTIVITY SHOULD THEN GENERALLY MOVE NWWD AND BECOME DOMINANT WEST OF
TUCSON AFTER MIDNIGHT INTO THE EARLY MORNING HOURS. AT ANY RATE...
THE MAIN THREATS WILL BE STRONG WIND GUSTS AND HEAVY RAINFALL.
TUE-WED...
27/00Z GFS/ECMWF WERE SIMILAR WITH DEPICTING DECREASED COVERAGE OF
SHOWERS/TSTMS AS THE MID-LEVEL STEERING FLOW BECOMES INCREASINGLY
WLY. THERE WILL BE ENOUGH MOISTURE TO MAINTAIN SCATTERED MOSTLY
AFTERNOON AND EVENING SHOWERS/TSTMS EAST-TO-SOUTH OF TUCSON WITH
LESSER PRECIP CHANCES NORTHWEST OF TUCSON.
THUR-SAT...
GFS/ECWMF WERE SIMILAR WITH DEPICTING INCREASING MOISTURE ACROSS SE
AZ AS THE UPPER HIGH BECOMES CENTERED NEAR THE FOUR CORNERS REGION.
THESE SOLUTIONS DIVERGED FROM PREVIOUS SOLUTIONS THAT DEPICTED A
POTENTIAL DRYING TREND ESPECIALLY ACROSS WRN SECTIONS BY EARLY NEXT
WEEKEND. HAVE ALSO NOTED THAT THE ECMWF WAS MARKEDLY MORE ROBUST
WITH QPF/S AND THE POTENTIAL FOR HEAVY RAINFALL VERSUS THE GFS.
STILL MUCH TOO SOON TO HAVE HIGH CONFIDENCE IN JUST ONE SOLUTION OF
MEDIUM RANGE FORECAST MODELS. AT ANY RATE...HAVE OPTED TO INCREASE
INHERITED POPS SOMEWHAT...ESPECIALLY BY NEXT SAT SCATTERED COVERAGE
OF SHOWERS/TSTMS IS EXPECTED TO OCCUR ACROSS MUCH OF THE AREA.
HIGH TEMPS THRU SAT WILL GENERALLY BE QUITE CLOSE TO SEASONAL
NORMALS. THE EXCEPTION WILL BE WED-THUR WHEN HIGH TEMPS ARE FORECAST
TO AVERAGE ABOUT 2-5 DEGS F OR SO ABOVE NORMAL.
&&
.AVIATION...VALID THRU 28/12Z.
EXPECT SCATTERED TSRA/SHRA THRU EARLY MONDAY MORNING. MVFR VSBYS
SHOULD OCCUR WITH THE STRONGER TSRA ALONG WITH WIND GUSTS TO NEAR
40-45 KTS. CLOUD DECKS WILL GENERALLY BE AT 7-12K FT AGL THRU THE
PERIOD. AVIATION DISCUSSION NOT UPDATED FOR TAF AMENDMENTS.
&&
.FIRE WEATHER...SCATTERED MOSTLY AFTERNOON AND EVENING THUNDERSTORMS
WILL PREVAIL THIS WEEK. EXPECT STRONG...GUSTY AND ERRATIC WINDS NEAR
THE STRONGER STORMS. OTHERWISE...NORMAL DIURNAL WIND TRENDS WILL
OCCUR WITH OCCASIONAL GUSTS DURING THE AFTERNOON HOURS DUE TO
DAYTIME HEATING.
&&
.TWC WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
VISIT US ON FACEBOOK...TWITTER...YOUTUBE...AND AT WEATHER.GOV/TUCSON
FRANCIS
AREA FORECAST DISCUSSION
NWS TUCSON AZ
355 AM MST SUN JUL 27 2014
.SYNOPSIS...EXPECT SCATTERED MAINLY AFTERNOON AND EVENING
THUNDERSTORMS THIS WEEK. SOME STORMS WILL GENERATE LOCALLY HEAVY
RAIN AND STRONG GUSTY WINDS.
&&
.DISCUSSION...KEMX WSR-88D DETECTED NUMEROUS 35-55 DBZ ECHOES ACROSS
WRN/CENTRAL PIMA COUNTY VALID 1050Z. ISOLATED MOSTLY LESS THAN 45
DBZ ECHOES WERE OCCURRING FROM TUCSON EWD/SWD TO THE NEW MEXICO/
INTERNATIONAL BORDERS. IR SATELLITE IMAGERY INDICATED MCS EXTENDING
FROM SOUTH CENTRAL AZ SEWD INTO NRN SONORA. VARIOUS RUC HRRR
SOLUTIONS HAVE BEEN VERY CONSISTENT WITH DEPICTING PRECIP TO
CONTINUE UNTIL AROUND MID-MORNING WEST OF TUCSON AS A MCV MOVES NWWD
ACROSS NWRN SONORA. MEANWHILE...THE ISOLATED SHOWERS/TSTMS ONGOING
FROM TUCSON EWD/SWD HAVE NOT BEEN WELL HANDLED BY THE RUC HRRR...
THAT HAD BEEN VERY CONSISTENT WITH DEPICTING PRECIP-FREE CONDITIONS
TO OCCUR THRU LATE THIS MORNING.
SUN-MON...
UPPER RIDGE IS PROGGED TO AMPLIFY OVER THE WRN CONUS. AMPLE MOISTURE
WILL BE AVAILABLE TO SUPPORT SCATTERED SHOWERS/TSTMS...WITH THE BULK
OF THE ACTIVITY TO OCCUR DURING THE AFTERNOON/EVENING HOURS.
ALTHOUGH NO TWO DAYS ARE EXACTLY IDENTICAL DURING THE MONSOON...FROM
A NWP MODEL PERSPECTIVE...THERE APPEAR TO BE SIMILARITIES WITH
HAPPENED SAT AND SAT NIGHT AND WHAT IS PROGGED TO OCCUR THIS PERIOD.
FOR INSTANCE...IF CLEARING IS SUFFICIENT ACROSS ERN SECTIONS DURING
THE MORNING HOURS...THEN SHOWER/TSTM INITIATION SHOULD OCCUR EAST-
TO-SOUTH OF TUCSON BY EARLY AFTERNOON. THIS ACTIVITY SHOULD THEN
MOVE GENERALLY NWWD AND BECOME DOMINANT WEST OF TUCSON AFTER
MIDNIGHT INTO THE EARLY MORNING HOURS. AT ANY RATE...THE MAIN
THREATS WILL BE STRONG WIND GUSTS AND HEAVY RAINFALL.
TUE-WED...
27/00Z GFS/ECMWF WERE SIMILAR WITH DEPICTING DECREASED COVERAGE OF
SHOWERS/TSTMS AS THE MID-LEVEL STEERING FLOW BECOMES INCREASINGLY
WLY. THERE WILL BE ENOUGH MOISTURE TO MAINTAIN SCATTERED MOSTLY
AFTERNOON AND EVENING SHOWERS/TSTMS EAST-TO-SOUTH OF TUCSON WITH
LESSER PRECIP CHANCES NORTHWEST OF TUCSON.
THUR-SAT...
GFS/ECWMF WERE SIMILAR WITH DEPICTING INCREASING MOISTURE ACROSS SE
AZ AS THE UPPER HIGH BECOMES CENTERED NEAR THE FOUR CORNERS REGION.
THESE SOLUTIONS DIVERGED FROM PREVIOUS SOLUTIONS THAT DEPICTED A
POTENTIAL DRYING TREND ESPECIALLY ACROSS WRN SECTIONS BY EARLY NEXT
WEEKEND. HAVE ALSO NOTED THAT THE ECMWF WAS MARKEDLY MORE ROBUST
WITH QPF/S AND THE POTENTIAL FOR HEAVY RAINFALL VERSUS THE GFS.
STILL MUCH TOO SOON TO HAVE HIGH CONFIDENCE IN JUST ONE SOLUTION OF
MEDIUM RANGE FORECAST MODELS. AT ANY RATE...HAVE OPTED TO INCREASE
INHERITED POPS SOMEWHAT...ESPECIALLY BY NEXT SAT SCATTERED COVERAGE
OF SHOWERS/TSTMS IS EXPECTED TO OCCUR ACROSS MUCH OF THE AREA.
HIGH TEMPS THRU SAT WILL GENERALLY BE QUITE CLOSE TO SEASONAL
NORMALS. THE EXCEPTION WILL BE WED-THUR WHEN HIGH TEMPS ARE FORECAST
TO AVERAGE ABOUT 2-5 DEGS F OR SO ABOVE NORMAL.
&&
.AVIATION...VALID THRU 28/12Z.
EXPECT SCATTERED TSRA/SHRA THRU EARLY MONDAY MORNING. MVFR VSBYS
SHOULD OCCUR WITH THE STRONGER TSRA ALONG WITH WIND GUSTS TO NEAR
40-45 KTS. CLOUD DECKS WILL GENERALLY BE AT 7-12K FT AGL THRU THE
PERIOD. AVIATION DISCUSSION NOT UPDATED FOR TAF AMENDMENTS.
&&
.FIRE WEATHER...SCATTERED MOSTLY AFTERNOON AND EVENING THUNDERSTORMS
WILL PREVAIL THIS WEEK. EXPECT STRONG...GUSTY AND ERRATIC WINDS NEAR
THE STRONGER STORMS. OTHERWISE...NORMAL DIURNAL WIND TRENDS WILL
OCCUR WITH OCCASIONAL GUSTS DURING THE AFTERNOON HOURS DUE TO
DAYTIME HEATING.
&&
.TWC WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
VISIT US ON FACEBOOK...TWITTER...YOUTUBE...AND AT WEATHER.GOV/TUCSON
FRANCIS
AREA FORECAST DISCUSSION
NWS PEACHTREE CITY GA
1012 AM EDT SUN JUL 27 2014
.UPDATE...
HIGH PRESSURE WILL CONTINUE ACROSS MUCH OF GA TODAY. ONLY SOME
CLOUDS EXPECTED...WITH VERY LITTLE CHANCE FOR ANY PRECIP UNTIL
VERY LATE IN THE AFTERNOON/EARLY EVENING ACROSS THE NORTHERN
ZONES.
HAVE ONLY MADE SOME VERY MINOR TWEAKS TO THE HOURLY GRIDS AND SKY
GRIDS. THE ISOLD POPS UP NORTH LATE STILL LOOK GOOD. ANY COMPLEX
THAT DEVELOPS ACROSS THE OHIO/TN VALLEY AND DROPS SE MAY BRUSH
EXTREME NORTHERN GA BY THE EARLY EVENING. THE HRRR CURRENTLY KEEPS
PRECIP NORTH OF THE STATE LINE...BUT WILL CONTINUE TO MONITOR.
&&
.PREV DISCUSSION... /ISSUED 737 AM EDT SUN JUL 27 2014/
SHORT TERM /TODAY THROUGH MONDAY NIGHT/...
/ISSUED AT 414 AM EDT SUN JUL 27 2014/
EXPECT A RATHER QUIET...BUT HOT WEATHER DAY TODAY AS MID AND UPPER
LEVEL RIDGING CONTINUES TO NOSE IN FROM THE WEST... RESULTING IN A
WARM/DRY WESTERLY FLOW. A FEW WEAK DISTURBANCES EMBEDDED IN THE NW
FLOW OVER THE TN VALLEY REGION WILL WARRANT A SLIGHT CHANCE OF
CONVECTION ACROSS FAR NORTH GA THIS AFTERNOON AND EVENING.
HOWEVER... THE MAIN WEATHER STORY IS A MUCH ADVERTISED COLD FRONT
THAT PUSHES INTO NORTH GA BETWEEN 5-7 AM MONDAY MORNING... ACROSS
THE ATLANTA METRO AREA BETWEEN NOON AND 2 PM MONDAY AFTERNOON...
THEN TO NEAR A COLUMBUS TO MACON LINE BETWEEN 4-6 PM MONDAY
AFTERNOON. MODELS ARE NOT SHOWING MUCH CONVECTION ALONG OR AHEAD OF
THE FRONT THROUGH MONDAY MORNING. THEN MODELS AGREE ON THE GREATER
CONVECTION FIRING ACROSS MAINLY CENTRAL GA MONDAY AFTERNOON AND
EVENING AS A STRONG DISTURBANCE INTERACTS WITH THE FRONT WHILE IT
PUSHES THROUGH A MOIST AND INCREASINGLY UNSTABLE ENVIRONMENT... WITH
EXPECTED MLCAPE VALUES IN THE 3000-4000 J/KG RANGE DURING THE HOT
MID-LATE AFTERNOON HOURS. AT THIS TIME... IT APPEARS A 40-50 KT MID
LEVEL WESTERLY FLOW WILL PRODUCE SUFFICIENT LOW LEVEL SHEAR TO
SUPPORT ISOLATED STRONG TO SEVERE STORMS ACROSS PARTS OF CENTRAL GA
MONDAY AFTERNOON AND EVENING ALONG AND AHEAD OF THE FRONT. AS A
RESULT... SPC HAS POSTED A SLIGHT RISK AREA GENERALLY ALONG AND
SOUTH OF A COLUMBUS TO MACON LINE FOR MONDAY AFTERNOON AND
EVENING... WITH THE MAIN THREATS BEING LARGE HAIL AND DAMAGING
WINDS. EXPECT THIS SEVERE POTENTIAL TO PUSH SOUTH OF THE FORECAST
AREA BY 9-10 PM MONDAY EVENING AS THE FRONT EXITS THE REGION. BEHIND
THE FRONT... EXPECT CLEARING CONDITIONS AS A COOLER/DRIER AIR MASS
SPREADS OVER THE FORECAST AREA THROUGH MONDAY NIGHT.
AS FOR TEMPS... HIGH PRESSURE INFLUENCE FROM THE WEST AND A HOT/DRY
WESTERLY FLOW WILL PUSH HIGHS TODAY WELL INTO THE 90S FOR MOST
AREAS... BUT NO RECORD HIGHS ARE EXPECTED TO BE BROKEN. THE WARM
DAYTIME TEMPS WILL HAVE TROUBLE COOLING OVERNIGHT... WITH LOWS
EXPECTED TO HOLD IN THE LOWER TO UPPER 70S FOR MOST AREAS TONIGHT.
THIS COULD RESULT IN A FEW MAX LOW TEMPS BEING BROKEN TONIGHT. WILL
HAVE TO MONITOR THIS CLOSELY. CLOUDS AND COOLER TEMPS BEHIND THE
FRONT WILL HELP HOLD HIGHS IN THE 80S ACROSS MUCH OF NORTH GA ON
MONDAY. HOWEVER... DAYTIME HIGHS ACROSS CENTRAL GA WILL BE ALLOWED
TO WARM WELL INTO THE 90S AHEAD OF THE APPROACHING COLD FRONT MONDAY
AFTERNOON.
39
LONG TERM /TUESDAY THROUGH SATURDAY/...
/ISSUED AT 414 AM EDT SUN JUL 27 2014/
THE FRONTAL BOUNDARY THAT AFFECTS THE STATE MONDAY WILL BE SOUTH OF
THE CWA BY 12Z TUE. THIS FRONTAL PASSAGE USHERS IN A AN UPPER
LEVEL DEEP LONG WAVE TROUGH WHICH REMAINS POSITIONED OVER THE AREA
THROUGH MUCH OF NEXT WEEK...KEEPING LOWER DEW POINTS AND COOLER
TEMPERATURES IN PLACE AT LEAST THROUGH WED/THU. MOISTURE BEGINS TO
INCREASE AGAIN BY THE END OF THE WORK WEEK ACROSS SOUTHERN PORTION
OF OUR CWA. WILL KEEP DIURNALLY DRIVEN SLIGHT TO LOW CHANCE POPS
IN ACROSS THE AREA DAYS 6 AND 7. BEGINNING TUESDAY...SHOULD SEE
BELOW AVERAGE TEMPERATURES WITH HIGHS IN THE UPPER 70S NORTH AND
LOW 80S ELSEWHERE...AND LOWS IN THE 60S. TEMPS WILL REBOUND BY
THU/FRI WITH NEAR NORMAL READINGS BY THEN.
01
CLIMATE...
RECORDS FOR 07-28
MAX TEMPERATURE MIN TEMPERATURE
STATION HIGH LOW HIGH LOW
------- ---------- ---------- ---------- ----------
KAHN 103 1952 75 1977 77 1936 59 1911
1926
KATL 101 1952 69 1977 77 1981 62 1911
KCSG 100 1993 81 1977 77 2010 67 1954
1952
KMCN 101 1993 76 1977 77 1958 62 1911
1952 1936
RECORDS FOR 07-29
MAX TEMPERATURE MIN TEMPERATURE
STATION HIGH LOW HIGH LOW
------- ---------- ---------- ---------- ----------
KAHN 103 1952 69 1984 76 1993 60 1911
1981
KATL 103 1952 73 1984 77 1993 63 1977
1926 1986
1896
KCSG 101 1952 74 1984 78 2010 65 1994
KMCN 104 1986 74 1984 78 1986 63 1897
1952
RECORDS FOR 07-30
MAX TEMPERATURE MIN TEMPERATURE
STATION HIGH LOW HIGH LOW
------- ---------- ---------- ---------- ----------
KAHN 102 1999 69 1984 76 2010 60 1925
1915
KATL 98 1986 68 1984 78 1896 61 1936
1980
KCSG 102 2010 76 1984 79 2010 65 1957
1986
KMCN 103 1986 74 1984 76 2010 62 1920
2008
1958
RECORDS FOR 07-31
MAX TEMPERATURE MIN TEMPERATURE
STATION HIGH LOW HIGH LOW
------- ---------- ---------- ---------- ----------
KAHN 103 1999 71 1916 76 1931 59 1936
KATL 99 1999 62 1936 78 1915 59 1936
1986 1896
1980
KCSG 104 1986 74 1997 78 2011 66 1997
1981 2010
KMCN 105 1986 68 1936 77 1931 61 1936
AVIATION...
12Z UPDATE...
VFR CONDITIONS ARE EXPECTED THROUGH THE TAF PERIOD. SCT MID LEVEL CU
WILL DEVELOP BY LATE MORNING AND PERSIST THRU THE AFTERNOON. DRY
HIGH PRESSURE INFLUENCE FROM THE WEST WILL HINDER ANY CONVECTIVE
THREAT TODAY. A COLD FRONT WILL PUSH INTO NORTH GA TONIGHT... THEN
ACROSS THE ATLANTA TAF SITES BETWEEN 15-17Z MONDAY. ASSOCIATED MID
LEVEL CIGS SHOULD SPREAD INTO THE ATLANTA TAF SITES BETWEEN 09-12Z
MONDAY...WITH SCT SHOWERS ALONG THE FRONT WARRANTING A PROB30 -SHRA
15Z-18Z MONDAY... WITH LITTLE TSRA THREAT EXPECTED AT THIS TIME.
WEST WINDS WILL INCREASE TO AROUND 10-12KTS BY MID-LATE THIS MORNING
WITH HIGHER GUSTS THRU THE AFTERNOON. EXPECT WSW WINDS 6-8KTS
TONIGHT...THEN WINDS SHIFT NW AROUND 10-12KTS BETWEEN 15-17Z MONDAY.
//ATL CONFIDENCE...12Z UPDATE...
MEDIUM CONFIDENCE ON TIMING OF FROPA ON MONDAY WITH ASSOCIATED
CONVECTION. HIGH ON ALL OTHER ELEMENTS.
39
&&
.PRELIMINARY POINT TEMPS/POPS...
ATHENS 96 74 92 66 / 10 20 30 5
ATLANTA 93 76 90 67 / 10 20 30 5
BLAIRSVILLE 88 68 82 58 / 20 30 20 10
CARTERSVILLE 93 73 89 64 / 10 30 20 5
COLUMBUS 96 77 94 69 / 10 10 40 10
GAINESVILLE 92 74 88 66 / 10 20 30 10
MACON 96 75 95 67 / 10 10 30 10
ROME 93 73 89 65 / 10 30 20 5
PEACHTREE CITY 93 72 91 65 / 10 10 30 5
VIDALIA 97 78 96 72 / 10 10 40 30
&&
.FFC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
Area Forecast Discussion
National Weather Service Lincoln IL
1046 AM CDT Sun Jul 27 2014
.DISCUSSION...
ISSUED 1045 AM CDT Sun Jul 27 2014
Forecast generally looks on track today and main adjustment is
low cloud cover lingering longer than earlier expected se of I-55.
Skies should still become partly to mostly sunny across central
and evenually eastern IL during the afternoon. Will continue
small chances of showers and thunderstorms over eastern IL mainly
east of I-57 this afternoon. SPC has slight risk of severe storms
from the IL/IN border east across IN/KY/OH with moderate risk over
in the foothills of the Appalachians in eastern KY and southern OH.
Cold front was pushing se into far southeast IL near the Wabash
River late this morning with WNW winds increasing behind the front
over central IL and gusting 15-25 mph over IL river valley. Still
muggy dewpoints in the low to mid 70s se of IL river and upper 60s
nw of IL river. Dewpoints drop off into the upper 50s and lower
60s upstream near the IA/IL border and should advect se into
central IL during the afternoon. Southeast IL will still be muggy
today where dewpoints currently in mid 70s but should slip into
the mid to upper 60s during the afternoon. Highs in the low to mid
80s look on track today with return of more sunshine with some
upper 80s near Lawrenceville.
07
&&
.AVIATION...
ISSUED 655 AM CDT Sun Jul 27 2014
Cold frontal boundary pushing into central IL roughly aligned from
KSPI-KAAA-KBMI as of 1130Z. Along the boundary a combination of a
shower band and locally dense fog is noted in surface obs and
radar imagery. Another hour or two of IFR-VLIFR vsby/cigs in fog
possible before daytime heating raises ceilings. Isold tsra will
remain possible in the vicinity of the boundary through this
afternoon causing isold mvfr vsby/cigs, but probabilities are too
low for mention in TAFs. Cloud cover becoming sct-bkn030-050
after 14Z. After 00Z- 02Z...clearing skies expected. Light winds
becoming NW and increasing to 12-18G20-25 kts through 18Z. Winds
becoming less gusty after 00Z and gradually decreasing overnight.
Onton
&&
.PREV DISCUSSION...
ISSUED 245 AM CDT Sun Jul 27 2014
Sfc map a mess in the wake of yesterday evenings convection. Broad
sfc trof/frontal boundary hung up over the region with light and
variable winds. Some patchy fog out there, with only a couple
sites dropping to a mile vis this morning. Some convection blowing
up over the area turning over some of the air and helping to block
much more of a vis drop in that area...and potentially limiting
the temp drop predawn. Even high res short term models not
handling the current conditions well, much less the next 12 hours.
Many mesoscale dynamics out there not being represented. Front
still not yet through the region...and first issue with the
forecast will be hanging on to pops, particularly in the east with
the frontal passage later mid day and this afternoon.
SHORT TERM...Today and tomorrow...
Keeping chances in for scattered showers and thunderstorms until
the front can progress through the area. Though today is expected
to get warm in front of the boundary...tomorrow is expected to see
signif cooler temps with some relatively drier air filtering in.
Precip chances drop out of the forecast for tonight and tomorrow.
But it bears mentioning that todays pops will be complicated by
small perturbations that are not being resolved well in the
models. HRRR is closest with some approximation of the line of
showers and thunder across central ILX...and some reflection of
the wave interacting with the stalled boundary out in KS. NAM also
trying to key in on it...though it dissolves rather quickly in the
HRRR, and the NAM sends it further eastward, diving sw of ILX and
interacting with the boundary later tonight well out of ILX. More
eastward progression with that disturbance may well change the
outcome of the mid day and afternoon ts chances.
LONG TERM...Tuesday through Saturday...
Cooler air immediately behind the front begins to slowly warm back
up on Tuesday by a few degrees a day. Northwesterly flow dominates
and a deep low digging in a trof over the eastern half of the
CONUS. From mid week on, chances begin to increase with afternoon
instability showers under the deepening cyclonic flow aloft, with
a more stormy afternoon summer pattern. But will be very scattered
and low in coverage. Timing with the next wave diving into the
trof aloft bringing better chances...is lacking continuity in
models. End of the week have better chances for some rainfall...
but certainty and coverage will keep the chances low and diffuse.
HJS
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
907 AM CDT SUN JUL 27 2014
.DISCUSSION...
322 AM CDT
SYNOPSIS...ONE MORE DAY OF A DIFFICULT AND MESSY PATTERN THAT WILL
RESULT IN SHOWERS AND THUNDERSTORMS ACROSS THE REGION. NO SEVERE
STORMS ARE EXPECTED. TEMPERATURES FALL THIS AFTERNOON AND REMAIN
BELOW NORMAL THROUGH THE REST OF THE WEEK. WE DRY OUT MONDAY AND
THEN HAVE LOW CHANCES OF PRECIP TUESDAY THROUGH SATURDAY.
TODAY AND TONIGHT...
AN UPPER LEVEL LOW IS OVER NORTHERN MINNESOTA WHILE A LARGER LOW IS
OVER NORTHERN QUEBEC. A SHORTWAVE TROUGH IS ALSO OVER EASTERN IOWA
WITH CONVECTION OVER CENTRAL WI. SPOTTY SHOWERS/SPRINKLES HAVE
SPROUTED OVER SOUTHEAST WI AND NOT EXPECTING MUCH ACTIVITY FROM
THOSE SPRINKLES. ADDITIONAL MORE IMPRESSIVE CONVECTION HAS FIRED
ALONG A WEAK BOUNDARY OVER CENTRAL IL. MAY SEE A FEW STORMS SOUTH OF
A PERU TO RENSSELAER LINE EARLY THIS MORNING.
FOG IS PRESENT OVER MUCH OF THE FORECAST AREA THIS MORNING AS
WELL. CLOUD COVER IS EXPANDING FROM SOUTH TO NORTH AND VSBY
INCREASES AS THE CLOUDS MOVE OVERHEAD. AS SUCH WILL HOLD OFF ON A
DENSE FOG ADVISORY FOR NOW AND SEE HOW THE CLOUD COVER SPREADS
ACROSS THE REGION.
EXPECTING ADDITIONAL CONVECTION TO FIRE AHEAD OF THE SHORTWAVE THIS
MORNING AND MOVE INTO NORTH CENTRAL IL. INSTABILITY MAY BE
LIMITED...BUT SOME THUNDER SHOULD BE REALIZED BASED ON
OBSERVATIONAL TRENDS UPSTREAM. THE SHOWERS AND STORMS WILL PUSH
EAST INTO THE AFTERNOON AS THE SHORTWAVE MOVES THROUGH. A COLD
FRONT CURRENTLY ACROSS NW WI THROUGH CENTRAL IA WILL ALSO
TRANSVERSE THE REGION AHEAD OF THE UPPER LEVEL LOW. THE LOW WILL
SWING OVER THE LAKE THIS AFTERNOON AND EXPECTING ADDITIONAL
ISOLATED TO SCATTERED STORMS WITH THIS FEATURE. TODAY WILL NOT BE
A WASH OUT HOWEVER AND THERE SHOULD BE PLENTY OF DRY HOURS.
ISOLATED SHOWERS CONTINUE INTO THE EVENING AND THEN THE BACK SIDE
OF THE UPPER LEVEL TROUGH SLIDES SOUTH THROUGH THE REGION
OVERNIGHT CLEARING OUT THE CLOUDS.
GUSTY WINDS ARE EXPECTED...AT TIMES TO 30 MPH THIS AFTERNOON.
WITH THE STRONG WINDS OVER LAKE MICHIGAN ORIENTED PARALLEL TO THE
FETCH...WAVES WILL BUILD CONSIDERABLY TONIGHT AND PERSIST INTO
MONDAY...AND A BEACH HAZARDS STATEMENT WILL GO INTO EFFECT FOR ALL
LAKE ADJACENT COUNTIES IN THE FORECAST AREA.
CLOUD COVER SHOULD STAY WITH US MOST OF THE DAY LIMITING HOW WARM WE
GET AGAIN. HIGHS WILL VARY FROM AROUND 80 NORTH TO THE MID 80S
SOUTH WHERE THERE COULD BE MORE SUNSHINE. TEMPS AND DEWPOINTS WILL
FALL THIS AFTERNOON THOUGH AS COOLER AIR MOVES IN BEHIND THE COLD
FRONT.
MONDAY...
THE UPPER LEVEL LOW WEAKENS TO AN OPEN TROUGH AND THEN MERGES WITH
THE STRONGER LOW OVER QUEBEC MONDAY NIGHT. WE STAY STUCK IN AN
UPPER LEVEL PATTERN WITH A RIDGE TO THE WEST AND TROUGH TO THE
EAST. THE SURFACE LOW MOVES OVER NEW ENGLAND MONDAY MORNING AND
HIGH PRESSURE BUILDS OVER THE PLAINS. MONDAY LOOKS DRY WITH WEAK
VORTICITY STREAMERS PASSING BY OVERHEAD. HIGHS WILL BE WELL BELOW
NORMAL IN THE LOW TO MID 70S. ONSHORE FLOW WILL KEEP THE LAKEFRONT
NEAR 70. THEN A BEAUTIFUL NIGHT FOR SLEEPING IS IN STORE WITH LOWS
IN THE MID 50S...EXCEPT FOR AROUND 60 DOWNTOWN.
TUESDAY THROUGH SATURDAY...
WE REMAIN IN THE STAGNANT UPPER LEVEL PATTERN WITH A SURFACE HIGH
OVER THE PLAINS. KEPT PERIODIC LOW CHANCES OF SHOWERS AND STORMS IN
THE EXTENDED FORECAST AS VORTICITY STREAMERS CONTINUE TO ROTATE
THROUGH THE REGION. MOISTURE IS NOT PLENTIFUL SO NOT EXPECTING MUCH
PRECIP AT THIS TIME. TEMPERATURES ALSO REMAIN BELOW NORMAL IN THE
70S WITH A FEW SITES MAYBE REACHING 80.
JEE
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 14Z...
* SCATTERED TSRA 16Z-19Z.
* CHANCE OF SHRA THIS AFTERNOON INTO EARLY THIS EVENING.
* STRONG/GUSTY WEST/NORTHWEST WINDS LATE MORNING THRU THIS EVENING.
* NORTH/NORTHEAST WINDS MONDAY MORNING.
* POSSIBLE MVFR CIGS TONIGHT. CMS
//DISCUSSION...UPDATED 12Z...
HIGH MOISTURE VALUES OVER THE AREA WILL SUPPORT FOG/LOW CLOUDS
THROUGH 13Z-14Z AND MAYBE EVEN TO 15Z ACROSS THE REGION. WOULD NOT
EXPECT CONDITIONS TO GET WORSE AT TAF SITES AFTER 12Z GIVEN
DAYBREAK AND AN INCREASING WIND FLOW.
A STRONG UPPER LEVEL LOW PRESSURE MOVING INTO NORTHWEST WI AS OF
12Z WILL ROTATE SOUTHEASTWARD OVER CHICAGO BY MID-AFTERNOON. JUST
AHEAD OF THIS WILL EXIST A FAIR AMOUNT OF LIFT AND UPPER
SUPPORT...WHICH OVERRIDING A COLD FRONT WITH INSTABILITY ALONG IT
WILL LIKELY SUPPORT THE DEVELOPMENT OF A LINE OF SHRA/TSRA. HOW
FAR SOUTH THIS WILL EXTEND IS UNCERTAIN BUT AT THIS TIME BELIEVE
ENOUGH THAT IT WARRANTS INCLUSION INTO THE TAF. AS THE HEART OF
THE UPPER LOW MOVES OVER THE AREA DURING THE MID TO LATE
AFTERNOON...WOULD EXPECT SCATTERED SHOWERS WITH POSSIBLY ISOLATED
STORMS.
BEHIND THE COLD FRONTAL PASSAGE LATE THIS MORNING/EARLY
AFTERNOON...THERE WILL BE A SHARP INCREASE IN THE WIND SPEEDS
FROM THE WEST-NORTHWEST. OCCASIONAL GUSTS IN EXCESS OF 25 KT ARE
PROBABLE. A SECONDARY COLD FRONT DROPPING SOUTHWARD LATE THIS
AFTERNOON WILL LIKELY KEEP SOME GUSTS INTO THE EVENING PERIOD DUE
TO ITS COOL AIR ADVECTION. THIS FRONT WILL ALSO LIKELY PROVIDE
SOME FOCUS FOR MVFR OR NEAR-MVFR CLOUDS THIS EVENING INTO EARLY
OVERNIGHT.
//ORD AND MDW CONFIDENCE...UPDATED 14Z...
* MEDIUM FOR TSRA 16Z-19Z.
* LOW FOR SHRA THIS AFTERNOON/EARLY EVENING.
* HIGH FOR WINDS THROUGH THIS AFTERNOON...MEDIUM TONIGHT/MONDAY.
* LOW FOR MVFR CIGS TONIGHT. CMS
//OUTLOOK FOR ORD/MDW FOR 00Z TUESDAY-12Z SUNDAY...UPDATED 12Z...
MONDAY NIGHT...VFR.
TUESDAY...SLIGHT CHANCE OF AFTERNOON TSRA.
WEDNESDAY...SLIGHT CHANCE OF TSRA.
THURSDAY-SATURDAY...SLIGHT CHANCES OF TSRA. NORTHEAST WINDS.
MTF
&&
.MARINE...
300 AM CDT
AN ACTIVE AND ATYPICAL SUMMERTIME PATTERN WILL UNFOLD ACROSS THE
LAKE THIS AFTERNOON THROUGH MONDAY NIGHT. LOW PRESSURE OVER THE
MIDDLE OF LAKE MICHIGAN BY MID TO LATE MORNING WILL MOVE EASTWARD
AND SLOWLY DEEPEN THIS AFTERNOON INTO TONIGHT. AS THIS OCCURS...COOL
AIR ADVECTION ON ITS BACKSIDE WITHIN A TIGHTENING PRESSURE
GRADIENT WILL DRIVE STRONG NORTHERLY WINDS. THESE WINDS LOOK TO
COME UP QUICKLY LATE THIS AFTERNOON AND BE MAXIMIZED THIS EVENING
INTO EARLY OVERNIGHT AND IT IS THEN WHEN OCCASIONAL GALE FORCE
GUSTS COULD OCCUR...ESPECIALLY OVER THE CENTRAL AND SOUTHERN PART
OF THE LAKE AND INTO THE INDIANA NEARSHORE. WINDS WILL BE SLOW TO
DIMINISH DURING MONDAY BUT THEN QUICKLY DROP MONDAY NIGHT. GIVEN
THE LONG FETCH THAT WILL BE REALIZED WAVES WILL BE ON THE UPPER
END OF THE SPECTRUM FOR SUMMERTIME WITH 7 TO 10 AND OCCASIONAL
HIGHER WAVES IN THE CENTRAL AND SOUTHERN PART OF THE LAKE INTO THE
INDIANA AND POSSIBLY ILLINOIS NEARSHORE AREAS. STRONG CANADIAN
HIGH PRESSURE FOR MID-SUMMER OVER THE NORTHERN PLAINS ON MONDAY
WILL EVOLVE EASTWARD OVER LAKE MICHIGAN BY MIDWEEK.
MTF
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...BEACH HAZARDS STATEMENT...ILZ014...10 PM SUNDAY TO 4 AM TUESDAY.
BEACH HAZARDS STATEMENT...ILZ006...10 PM SUNDAY TO 10 PM MONDAY.
IN...BEACH HAZARDS STATEMENT...INZ001-INZ002...6 PM SUNDAY TO 4 AM
TUESDAY.
LM...SMALL CRAFT ADVISORY...NEARSHORE WINTHROP HARBOR TO NORTHERLY IS
UNTIL 10 PM MONDAY.
SMALL CRAFT ADVISORY...LMZ742-LMZ743 UNTIL 4 AM TUESDAY.
SMALL CRAFT ADVISORY...LMZ744-LMZ745...3 PM SUNDAY TO 4 AM
TUESDAY.
&&
$$
VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
WWW.FACEBOOK.COM/US.NATIONALWEATHERSERVICE.CHICAGO.GOV
WWW.TWITTER.COM/NWSCHICAGO
WWW.YOUTUBE.COM/NWSCHICAGO
Area Forecast Discussion
National Weather Service Lincoln IL
656 AM CDT Sun Jul 27 2014
.DISCUSSION...
ISSUED 245 AM CDT Sun Jul 27 2014
Sfc map a mess in the wake of yesterday evenings convection. Broad
sfc trof/frontal boundary hung up over the region with light and
variable winds. Some patchy fog out there, with only a couple
sites dropping to a mile vis this morning. Some convection blowing
up over the area turning over some of the air and helping to block
much more of a vis drop in that area...and potentially limiting
the temp drop predawn. Even high res short term models not
handling the current conditions well, much less the next 12 hours.
Many mesoscale dynamics out there not being represented. Front
still not yet through the region...and first issue with the
forecast will be hanging on to pops, particularly in the east with
the frontal passage later mid day and this afternoon.
SHORT TERM...Today and tomorrow...
Keeping chances in for scattered showers and thunderstorms until
the front can progress through the area. Though today is expected
to get warm in front of the boundary...tomorrow is expected to see
signif cooler temps with some relatively drier air filtering in.
Precip chances drop out of the forecast for tonight and tomorrow.
But it bears mentioning that todays pops will be complicated by
small perturbations that are not being resolved well in the
models. HRRR is closest with some approximation of the line of
showers and thunder across central ILX...and some reflection of
the wave interacting with the stalled boundary out in KS. NAM also
trying to key in on it...though it dissolves rather quickly in the
HRRR, and the NAM sends it further eastward, diving sw of ILX and
interacting with the boundary later tonight well out of ILX. More
eastward progression with that disturbance may well change the
outcome of the mid day and afternoon ts chances.
LONG TERM...Tuesday through Saturday...
Cooler air immediately behind the front begins to slowly warm back
up on Tuesday by a few degrees a day. Northwesterly flow dominates
and a deep low digging in a trof over the eastern half of the
CONUS. From mid week on, chances begin to increase with afternoon
instability showers under the deepening cyclonic flow aloft, with
a more stormy afternoon summer pattern. But will be very scattered
and low in coverage. Timing with the next wave diving into the
trof aloft bringing better chances...is lacking continuity in
models. End of the week have better chances for some rainfall...
but certainty and coverage will keep the chances low and diffuse.
HJS
&&
.AVIATION...
ISSUED 655 AM CDT Sun Jul 27 2014
Cold frontal boundary pushing into central IL roughly aligned from
KSPI-KAAA-KBMI as of 1130Z. Along the boundary a combination of a
shower band and locally dense fog is noted in surface obs and
radar imagery. Another hour or two of IFR-VLIFR vsby/cigs in fog
possible before daytime heating raises ceilings. Isold tsra will
remain possible in the vicinity of the boundary through this
afternoon causing isold mvfr vsby/cigs, but probabilities are too
low for mention in TAFs. Cloud cover becoming sct-bkn030-050
after 14Z. After 00Z- 02Z...clearing skies expected. Light winds
becoming NW and increasing to 12-18G20-25 kts through 18Z. Winds
becoming less gusty after 00Z and gradually decreasing overnight.
Onton
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS WICHITA KS
859 AM CDT SUN JUL 27 2014
.MESOSCALE DISCUSSION...
ISSUED AT 859 AM CDT SUN JUL 27 2014
RADAR MOSAIC SUGGESTS A MESO VORT MAX HAS EVOLVED FROM THE
OVERNIGHT CONVECTION ACROSS SOUTHWEST KANSAS. THE HRRR AND RUC
SUPPORT CONVECTION FESTERING LONGER INTO MIDDAY AND PERHAPS EARLY
AFTERNOON ACROSS PORTIONS OF SOUTHERN KANSAS AS THIS FEATURES
MOVES EAST-SOUTHEAST ACROSS THE AREA. FORECAST HAS BEEN UPDATED TO
REFLECT LONGER DURATION...THOUGH ADDITIONAL TEMPORAL AND SPATIAL
AMENDMENTS MAY BE NEEDED BY LATE MORNING. OTHERWISE LESS HEAT AND
GRADUAL DRYING WILL TAKE PLACE TODAY.
KED
&&
.SHORT TERM...(TODAY THROUGH TUESDAY)
ISSUED AT 257 AM CDT SUN JUL 27 2014
A COLD FRONT WAS BISECTING THE CENTRAL PLAINS OVERNIGHT WITH
ISOLATED POST-FRONTAL SHOWERS AND THUNDERSTORMS. WHAT LITTLE SUPPORT
THERE IS FOR RENEWED DEVELOPMENT IS PROGGED TO SHIFT SOUTH AND WEST
OF THE FORECAST AREA DURING THE MORNING HOURS...ALTHOUGH AN ISOLATED
SHOWER OR TWO MAY LINGER THROUGH 15-16Z BEFORE SHIFTING SOUTH OF THE
AREA AS DRIER AIR ADVECTS SOUTH ACROSS THE AREA.
THE COLD FRONT WILL BRING MORE SEASONABLE AIR TO THE AREA TODAY WITH
HIGHS IN THE UPPER 80S AND LOW 90S. DRY AND SEASONABLY COOL AIR WILL
PERSIST THROUGH THE REMAINDER OF THE SHORT TERM PERIODS WITH DRY
CONDITIONS AND HIGHS IN THE 80S MON-TUE. MAINTAINED LOW POPS ALONG
THE WESTERN TIER OF THE FORECAST AREA AS A MOIST UPSLOPE FLOW REGIME
IS PROGGED WITHIN A WEAKLY CAPPED AIRMASS. SHOWERS AND THUNDERSTORMS
DEVELOPING ACROSS THE HIGH PLAINS MAY DRIFT EASTWARD IMPACTING THE
AREA LATE TUE WHILE BETTER CHANCES SHOULD REMAIN WELL WEST OF THE
FORECAST AREA.
.LONG TERM...(WEDNESDAY THROUGH SATURDAY)
ISSUED AT 257 AM CDT SUN JUL 27 2014
THE ECMWF AND GFS HAVE BEEN FAIRLY CONSISTENT BRINGING A SUBTLE WAVE
EAST/SOUTHEAST ACROSS THE CENTRAL PLAINS ON WED-WED NIGHT AND
MAINTAINED MID POPS WEIGHTED ACROSS THE SOUTHWEST ZONES. DUE TO
LIMITED INSOLATION/PRECIPITATION...HIGHS MAY STRUGGLE TO CLIMB OUT
OF THE 70S. THE GFS AND ECMWF REMAIN IN REASONABLE AGREEMENT
DEPICTING A LARGE TROUGH MEANDERING/RETROGRADING ACROSS THE MIDDLE
MISSISSIPPI VALLEY AREA THU-SAT. THIS WILL RESULT IN A PERIOD OF
UNSETTLED WEATHER WITH UNSEASONABLY COOL AIR AND CONTINUED CHANCES
FOR LIGHT PRECIPITATION INTO THE WEEKEND.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z MONDAY MORNING)
ISSUED AT 648 AM CDT SUN JUL 27 2014
ELEVATED POST FRONTAL CONVECTION CONTINUES JUST TO THE NORTH OF KAAO
NEAR KEWK AT THIS TIME...AS A WEAK COLD FRONT DROPS SOUTH ACROSS SRN
KS. EXPECT THIS ELEVATED CONVECTION TO PERSIST FOR A FEW MORE HOURS
THIS MORNING...POSSIBLY DROPPING SOUTH OVER THE KICT METRO AREA. SO
WILL INCLUDE A VCTS AND A TEMPO TSRA FOR THE KICT TAF FOR A FEW
HOURS THIS MORNING. WILL ALSO INCLUDE A VCTS FOR THE KHUT TAF AS
WELL...AS THIS ELEVATED ACTIVITY LINGERS NEAR THIS AREA AS WELL.
COULD SEE SOME VARIABLE WIND GUSTS TO 35 KTS FOR THE KICT TAF AS
THIS CONVECTION MOVES PAST.
EXPECT THE SRN KS FRONTAL BOUNDARY TO CONTINUE TO DROP SOUTH INTO OK
FOR THE MORNING HOURS...WITH DRIER AND MORE STABLE AIR WORKING
ACROSS MOST OF THE FORECAST AREA FOR THE AFTERNOON HOURS. SO WILL
ONLY KEEP THE TSRA GOING FOR THE MORNING. AFTER THIS DRIER AIR
MOVES IN...WILL GO WITH VFR CIGS FOR THE REST OF THE TAF TIME
FRAME.
KETCHAM
&&
.PRELIMINARY POINT TEMPS/POPS...
WICHITA-KICT 92 65 87 65 / 30 0 0 10
HUTCHINSON 91 64 86 64 / 30 0 0 10
NEWTON 92 64 85 64 / 30 0 0 10
ELDORADO 92 64 86 62 / 50 0 0 0
WINFIELD-KWLD 92 66 87 65 / 20 0 0 0
RUSSELL 87 63 86 63 / 10 0 0 10
GREAT BEND 88 63 86 63 / 20 0 0 10
SALINA 90 62 87 62 / 10 0 0 10
MCPHERSON 91 64 86 64 / 10 0 0 10
COFFEYVILLE 96 64 88 62 / 20 0 0 0
CHANUTE 94 63 86 61 / 20 0 0 0
IOLA 93 62 85 60 / 10 0 0 0
PARSONS-KPPF 95 64 87 61 / 10 0 0 0
&&
.ICT WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS LOUISVILLE KY
657 AM EDT Sun Jul 27 2014
...Updated Aviation Discussion...
...Forecast Update...
Issued at 645 AM EDT Sun Jul 27 2014
Made minor updates to account for continuing convection across
central KY and southern IN. Heavy to torrential rainfall continues
to be the primary threat as a relative min in severe activity
briefly occurs. Gusty winds will continue in and around storms and
the gradient winds will increase as the diurnal heating machine
kicks in. The HRRR has been one of the best performing models
through the overnight period so if this pans out, this relative min
could continue through the next few hours before ramping back up
again. Shear is already beginning to increase and instability will
be on the rise.
.SHORT TERM (Now through Monday)...
Issued at 359 AM EDT Sun Jul 27 2014
...Severe weather threat continues this morning through much of
today...
Currently:
The MCS that rolled through the forecast area late Saturday night
has not stopped convection from re-firing in a line extending
currently from roughly Daviess County, IN southeastward through
Elizabethtown, KY. These storms have developed near theta-e
advecting in from the west, along with an increase of low-level
PWATs, per the CIMMS NearCast model. This cluster has all of the
features of being severe; however, latest available AMDAR soundings
show a shallow stable layer, which may help to keep the worst of the
winds aloft. Regardless, the concern is certainly there that despite
that these storms should be primarily elevated, they seem to be able
to overcome the layer and go surface-based. An additional concern
that was not present with the previous MCS is that a directional
shear component has been added to the increase in speed shear as the
low-level jet ramps up and surface southerly winds persist.
Today:
Continued uncertainty exists for the exact evolution of today`s
storms, although given how easily convection was able to develop
overnight and how quickly the local atmosphere was able to recover
behind the MCS, this is concerning given all of the other parameters
that will line up to create a severe threat for much of central KY
and south-central IN. The worked over atmosphere has not stopped
storm development. Models are showing 0-6km bulk shear today will be
increasing from approximately 30kts. in southern KY to 50kts. north
of the Ohio River to 40kts in the south to 60kts. in the north by
late today. SBCAPE, while some already exists this morning, will
increase to over 2500 J/kg under the sun today. The focus of where
storms will develop and how they`ll move will be a short-term,
mesoscale based forecasting approach as they ride leftover
boundaries and wherever the greater instability sets up, which
currently looks to be in southern and eastern KY. Hi-res models are
showing multiple rounds of storms but clearing out by late this
afternoon. Think this will be more dependent on the timing of the
front. The mode early on could be discrete supercells, congealing
into potentially a broken line as they merge and coalesce with one
another. The primary concern for any severe storms today will be
damaging winds and heavy to torrential rainfall, with secondary
concerns for hail and potentially an isolated tornado.
Highs today are expected to reach the upper 80s in the north and the
low 90s in the south, despite any cloud cover as the WAA pipeline
remains at full blast until the fropa.
Tonight through Monday:
Once the well-advertised cold front pushes through (expected to be
through the forecast area by tonight), the storms will go with it,
leaving clearing skies and a dry forecast for the overnight period.
However, clouds will clutter the skies once more on Monday with a
chance for showers, especially in the Bluegrass region and locations
east of I-65. This is as the upper low spins down into the region,
which will also bring significantly cooler temperatures. Look for
lows to range from the lower 60s in the north to the upper 60s in
the southeast. Highs on Monday will range from the mid 70s in the
north to around the 80 degree mark in the south.
.LONG TERM (Monday Night through Saturday)...
Issued at 245 AM EDT Sun Jul 27 2014
An amplified pattern over the CONUS will persist this week with
troughing noted over the Midwest providing unseasonably cool
weather.
Tues-Thurs we`ll be dry with sfc high pressure in the area.
Tuesday`s highs will flirt with record cold highs which are in the
70s at climate stations. Forecast highs for Tuesday range from
73-79 across the area. We`ll then see a little bit of a warm-up
into the upper 70s and lower 80s for Wed/Thu. Night time lows will
be in the upper 50s and lower 60s.
By Friday, the pattern looks to attempt to become more a of a split
flow with an upper low attempting to be cut off over the Midwest.
As shortwaves increase in the trough and upper low toward the end of
the week, rain/storm chances will re-emerge with on and off
showers/storms possible through the weekend.
&&
.AVIATION (12Z TAF Update)...
Issued at 651 AM EDT Sun Jul 27 2014
Difficult forecast for today as ongoing convection causes
uncertainty in how convection will evolve later today. A surface low
is progged over central IL and moving toward the NE. Aloft,
upper-level low pressure is rotating down from the NW as a deep
Canadian trough primes to take over the region.
Strong to severe thunderstorms will continue to threaten all three
terminals but given the uncertainty in timing, have not included
specifics other than VCTS (but even this is likely to change
throughout the day). Amendments will need to be made as storms
develop and threaten the terminals. The fropa is expected to have
cleared all three terminals sometime or shortly after 00Z Monday and
will take with it storm activity.
Winds will be a concern during the day as 15 to 20 knot
southwesterly gradient winds are expected with higher gusts. Winds
could be higher in or around any storms.
&&
.LMK WATCHES/WARNINGS/ADVISORIES...
KY...NONE.
IN...NONE.
&&
$$
Update.........lg
Short Term.....lg
Long Term......AMS
Aviation.......lg
AREA FORECAST DISCUSSION
NWS CARIBOU ME
1007 AM EDT SUN JUL 27 2014
.SYNOPSIS...
LOW PRESSURE WILL APPROACH FROM THE WEST TODAY. ANOTHER LOW WILL LIFT
NORTH ACROSS THE REGION MONDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
10 AM UPDATE...DECIDED TO PULL BACK ON THE TIMING OF THE SHOWERS
AND TSTMS BY ABOUT 2 HRS BASED ON THE LATEST RADAR AND SATELLITE
LOOPS. BEST SHOWER ACTIVITY WAS RUNNING N ACROSS THE WESTERN
MOUNTAINS INTO QUEBEC. MORE SUBSTANTIAL SHOWERS AND TSTMS WERE
STILL WELL BACK ACROSS SOUTHERN QUEBEC DOWN ACROSS VT & NH. THIS
AREA IS PICKED UP WELL BY THE LATEST RAP AND HRRR. THIS LARGER AREA
IS FORECAST TO PUSH ACROSS THE REGION AFTER 1 PM. BOTH MESOSCALE
GUIDANCE INDICATES THE POTENTIAL FOR SOME TSTMS TO BECOME STRONG
ACROSS PORTIONS OF THE CENTRAL HIGHLANDS DUE TO TERRAIN
ENHANCEMENT AND GOOD HEATING. ANOTHER AREA WILL BE INTERIOR
DOWNEAST AS MSAS AND LAPS SHOW A NOSE OF INSTABILITY(LIS AROUND -3)
PUSHING INTO THIS AREA. LAPS SOUNDINGS INDICATE DECENT
INSTABILITY IN THIS REGION PER 13Z OBS W/LIS DOWN TO -4 AND SB
CAPES AT 800 J/KG. POTENTIAL IN THIS AREA FOR SOME HAIL AND EVEN
GUSTY WINDS IF STORMS CAN BUILD ALONG W/HEAVY RAINFALL. WE WILL MONITOR
THIS REGION THIS MORNING FOR POSSIBLE ENHANCED WORDING.
ACTIVITY LOOKS LIKE IT WEAKENS AS IT PUSHES NE INTO A MORE STABLE
ENVIRONMENT. 12Z CAR SOUNDING QUITE STABLE TO START BUT HEATING
INTO EARLY AFTERNOON COULD CHANGE THINGS.
PREVIOUS DISCUSSION...
CLOUDS WILL BE ON THE INCREASE IN ADVANCE OF AN APPROACHING SHORT
WAVE TROF APPROACHING FROM THE WEST. THE CHANCE FOR SHOWERS WILL
INCREASE FROM WEST TO EAST ACROSS THE FORECAST AREA TODAY ALTHOUGH
MOST AREAS WILL REMAIN RAIN FREE THROUGH MIDDAY WITH THE BEST CHANCE
FOR SHOWERS THIS AFTERNOON. THERE WILL ALSO BE THE CHANCE FOR AN
AFTERNOON THUNDERSTORM AS THE PASSAGE OF SHORT WAVE TROF COINCIDES
WITH SOME INSTABILITY DUE TO AFTERNOON HEATING. SB CAPES ARE ONLY
EXPECTED TO MAXIMIZE AT AROUND 500 J/KG AND 0-6 KM SHEAR VALUES ARE
ONLY EXPECTED TO RANGE FROM 20-25 KT ON AVERAGE ACROSS THE REGION.
THINKING IS ANY STORMS THAT WOULD DEVELOP WOULD BE ON THE WEAKER
SIDE SO WE ARE NOT ANTICIPATING ANYTHING SEVERE AT THIS TIME
ALTHOUGH WITH PW/S INCREASING THERE COULD BE SOME HEAVY DOWNPOURS
WITH ANY STORMS. ANOTHER FACTOR LIMITING INSTABILITY WILL BE
SOUTHERLY BL WINDS OFF THE GULF OF MAINE. HIGHS TODAY WILL RANGE
FROM THE LOW TO MID 70S.
TONIGHT WILL BE MOSTLY CLOUDY IN THE WAKE OF THE EXITING SHORT WAVE
AND THE NEXT SHORT WAVE APPROACHING FROM THE WEST. A RATHER MOIST
AIR MASS WILL BE IN PLACE ACROSS THE REGION WITH LIGHT SOUTH TO
SOUTHEAST WIND. EXPECT MAINLY CLOUDY SKIES AND JUST THE CHANCE FOR
SHOWERS. PATCHY FOG IS EXPECTED TO DEVELOP ACROSS THE REGION WITH
AREAS OF FOG MORE PREVALENT ALONG THE DOWNEAST COAST. LOWS TONIGHT
AREV ONLY EXPECTED TO FALL TO AROUND 60 IN MOST LOCATIONS.
&&
.SHORT TERM /MONDAY THROUGH TUESDAY/...
EXPECT A RAINY START TO THE WORK WEEK. A VERY SLOW-MOVING FRONT WILL
BE DRAPED VERY NEAR THE WESTERN MAINE/EASTERN QUEBEC BORDER MONDAY
MORNING. LOW PRESSURE WILL SLIDE NORTHWARD ALONG THIS FRONT MONDAY
AFTERNOON AND EVENING AS THE BOUNDARY GRADUALLY SHIFTS EASTWARD. AS
SUCH, RAIN WILL SPREAD FROM SOUTH TO NORTH THROUGH THE DAY MONDAY.
EXTENSIVE CLOUD COVER WILL LIMIT INSTABILITY, BUT CAN`T RULE OUT A
FEW RUMBLES OF THUNDER IN THE AFTERNOON. THE LOW WILL LIFT NORTH OF
THE FORECAST AREA MONDAY NIGHT, ALLOWING THE RAIN TO BECOME MORE
SHOWERY IN NATURE.
TUESDAY IS STILL A BIT UNCERTAIN AS THE MODEL GUIDANCE IS STILL
HAVING A HARD TIME AGREEING ON HOW QUICKLY THE LOW WILL EXIT THE
REGION. THE ECMWF IS THE SLOWEST AND GIVES NORTHERN MAINE A GOOD
SLUG OF PRECIPITATION TUESDAY MORNING. FEEL THIS IS A BIT OVERDONE,
BUT DO THINK THAT SOME SHOWERS WILL LINGER THROUGH MUCH OF THE DAY
TUESDAY. IN ADDITION, THE WEAKENING FRONT WILL BE SOMEWHERE ACROSS
FAR DOWNEAST OR JUST OFF SHORE, WHICH COULD SERVE TO FOCUS SOME
AFTERNOON SHOWERS IN OUR SOUTHERN AREAS.
&&
.LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/...
THE MAIN WEATHER FEATURE FOR THE LONG TERM WILL BE AN UPPER LOW THAT
WILL REMAIN CENTERED NEAR HUDSON BAY ALL NEXT WEEK. IN ADDITION, THE
REMNANTS OF THE FRONT FROM EARLIER IN THE WEEK WILL LINGER ACROSS
THE GULF OF MAINE. WHILE NO ONE DAY PARTICULARLY LOOKS TO BE A
WASHOUT, CAN`T RULE OUT AT LEAST A SLIGHT CHANCE OF SHOWERS EACH
DAY. TEMPERATURES WILL BE NEAR OR A BIT BELOW SEASONAL NORMAL
THROUGH THE PERIOD.
&&
.AVIATION /14Z SUNDAY THROUGH THURSDAY/...
NEAR TERM: PATCHY MVFR/IFR CONDITIONS IN BR CAN BE EXPECTED UNTIL AROUND
SUNRISE. OTHERWISE VFR CONDITIONS WILL PREVAIL INTO THIS AFTERNOON.
SHOWERS ARE EXPECTED TO DEVELOP THIS AFTERNOON ALONG WITH THE CHANCE
FOR A THUNDERSTORM. ANY THUNDERSTORMS WILL BE RATHER ISOLATED IN
NATURE SO AT THIS POINT CONFIDENCE NOT THAT HIGH THAT ANY PARTICULAR
TERMINAL WILL BE IMPACTED THUS NO MENTION OF TSTMS IN THE TAF
FORECAST QUITE YET.
EXPECT MVFR CONDITIONS TO DEVELOP BY EARLY THIS EVENING AS LOW
LEVEL MOISTURE INCREASES ACROSS THE REGION. EXPECT WIDESPREAD MVFR
AND IFR CONDITIONS TONIGHT IN AREAS OF FOG AND LOWERING CIGS.
SHORT TERM: MVFR CONDITIONS ARE LIKELY MONDAY AND MONDAY NIGHT IN
WIDESPREAD RAIN, WITH LOCAL IFR POSSIBLE AT TIMES. ISOLATED
THUNDERSTORMS ARE POSSIBLE DURING THE AFTERNOON INTO THE EVENING.
CONDITIONS WILL GRADUALLY IMPROVE MONDAY MORNING, MAINLY AT THE
SOUTHERN TERMINALS, THOUGH SHOWERS WILL CONTINUE TO BE POSSIBLE
AREAWIDE. PREVAILING VFR NOT EXPECTED EVERYWHERE UNTIL TUESDAY
NIGHT/WEDNESDAY MORNING. VFR CONDITIONS WILL THEN CONTINUE THROUGH
THURSDAY.
&&
.MARINE...
NEAR TERM: WINDS/SEAS WILL REMAIN BELOW SMALL CRAFT ADVISORY
LEVELS THROUGH TONIGHT. VISIBILITY WILL BE REDUCED TO 1 TO 3 NM IN
PATCHY FOG THIS MORNING AND IN AFTERNOON SHOWERS/ISOLD THUNDER.
EXPECT VISIBILITY TO BE REDUCED TO 1 NM OR LESS TONIGHT IN AREAS
OF FOG.
SHORT TERM: A SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS MAY BE
NEEDED BY MONDAY AFTERNOON AS SOUTHERLY FLOW INCREASES IN RESPONSE
TO LOW PRESSURE MOVING UP ALONG THE SAINT LAWRENCE RIVER VALLEY.
WAVE GUIDANCE CONTINUES TO BE TOO AGGRESSIVE, BRINGING WAVES UP TO
8-10 FEET. SEAS OF 5 TO 7 FEET LOOK MORE REASONABLE, THOUGH EVEN
THIS COULD BE TOO GENEROUS. REGARDLESS, CONDITIONS WILL IMPROVE
DURING THE DAY TUESDAY AS THE LOW PULLS AWAY FROM THE REGION.
&&
.CAR WATCHES/WARNINGS/ADVISORIES...
ME...NONE.
MARINE...NONE.
&&
$$
NEAR TERM...DUDA/HEWITT
SHORT TERM...HASTINGS
LONG TERM...HASTINGS
AVIATION...DUDA/HEWITT/HASTINGS
MARINE...DUDA/HEWITT/HASTINGS
AREA FORECAST DISCUSSION
NWS WAKEFIELD VA
935 AM EDT SUN JUL 27 2014
.SYNOPSIS...
A STRONG COLD FRONT APPROACHES THE REGION FROM THE NORTHWEST THIS
AFTERNOON..THEN CROSSES THE AREA LATE TONIGHT AND MONDAY. HIGH
PRESSURE BUILDS INTO THE AREA FROM THE NORTHWEST TUESDAY THROUGH
THURSDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
MADE SOME CHANGES TO GRIDS BASED ON LATEST RADAR TRENDS SFC OBS
AND MODEL GUIDANCE. MAIN CHANGE WAS TO ACCOUNT FOR LINE OF
CONVECTION MARCHING EAST ACROSS THE NC PIEDMONT ATTM. HRRR SEEMS
TO HAVE BEST HANDLE ON THE CRNT TRENDS...SO INCREASED POPS TO
LIKELY ACROSS SRN MOST COUNTIES NEXT SVRL HRS AS THIS LINE MOVES
EAST.. VSBY SAT LOOP SHOWING SOME PARTIAL SUNSHINE AHEAD OF IT TO
KEEP THE LINE GOING.
LOWERED TMPS BY A CATEGORY MOST PLACES (CLOSER TO LAV GUID) GIVEN
ALL THE CLOUDS AND PCPN FROM THE MORNING CONVECTIVE COMPLEX. TUFF
CALL FOR SERN COUNTIES AS TMPS MAY GET TO 90 THERE...BUT THEN DROP
IN ANY CONVECTION BY ERLY AFTRN.
MAIN QUESTION FOR THIS AFTRN IS HOW MUCH HEATING WILL OCCUR BEHIND
THE FIRST DEPARTING S/W AND AHEAD OF NXT APPRCHG S/W NOW OVR KY
VLLY. LATEST DATA SUGGESTS THIS COMPLEX TAKING A MORE SOUTHERLY
ROUTE (ACROSS SRN HALF OF VA / NC THIS EVENING.
SPC CONTINUES TO HAVE FA OUTLOOKED IN SLGHT RISK WITH A RECENTLY
ISSUED PWO FOR AREAS TO OUR WEST. STAY TUNED.
&&
.SHORT TERM /MONDAY THROUGH TUESDAY NIGHT/...
THE STRONG COLD FRONT QUICKLY PUSHES ACROSS THE REGION ON MONDAY.
OVERNIGHT SHOWERS/STORMS SHOULD BECOME MORE FOCUSED ALONG THE COLD
FRONT AND RE-FIRE IN INTENSITY DUE TO THE ADDED LIFT. OVERALL...
PRECIP SHOULD BE CONFINED TO COASTAL AREAS UNTIL THE FRONT CAN
PUSH WELL TO THE SOUTHEAST OF THE AREA BY LATE AFTN/EARLY EVENING.
ALTHOUGH THE OVERALL SEVERE WEATHER THREAT IS DIMINISHED ON
MONDAY...A FEW STORMS COULD BECOME SEVERE AND BE CAPABLE OF
PRODUCING STRONG WINDS...LARGE HAIL...AND LOCALLY HEAVY RAINFALL.
WEST WINDS WILL BE BREEZY WITH GUSTS TO AROUND 25 MPH AS A COOLER
AND DRIER CANADIAN AIRMASS FILTERS INTO THE REGION FROM THE NW-N.
WINDS AND SUNSHINE WILL BE KEY PLAYERS IN HIGH TEMPS ON MONDAY.
CURRENT FORECAST RANGES FROM THE UPPER 80S NW TO 90-95 SE.
BNDRY PROGGED TO STALL INVOF GULF STREAM MON NIGHT AND TUE WHILE A
COOLER AND DRIER AIRMASS FILTERS IN FROM THE NORTH. KEPT SLGHT CHC
POPS ALONG SERN CSTL AREAS MON EVENING. LOWS IN THE 60S...XCPT L70S
SERN CSTL AREAS. DRY TUESDAY ALONG WITH LOWER HUMIDITY AS DEWPOINTS
DROP INTO THE 50S. PARTLY TO MOSTLY SUNNY. HIGHS IN THE L80S...U70S AT
THE BEACHES. LOWS IN THE MID-UPPER 50S W TO MID 60S AT THE BEACHES.
&&
.LONG TERM /WEDNESDAY THROUGH SATURDAY/...
GOING WITH A COMBINATION OF THE 12Z GFS AND 12Z ECMWF FOR THE
EXTENDED PERIOD. LONGWAVE TROF DIGS OVR THE MID ATLC REGION TUE NGT
INTO EARLY THU...BEFORE RETROGRADING BACK INTO THE OH AND MS VALLEYS
THU AFTN THRU SAT. A FRONTAL BOUNDARY WILL LINGER OFF THE MID ATLC
CST TUE NGT THRU FRI...THEN DRIFTS BACK TWD THE CST FRI NGT THRU
SAT. WILL MAINTAIN A DRY FCST FOR TUE NGT THRU FRI...THEN HAVE ADDED
SLGT CHC POPS FOR FRI NGT AND SAT. A MORE COMFORTABLE AIRMASS WILL
DOMINATE THE AREA TUE NGT THRU THU...BEFORE A GRADUAL INCREASE IN
HUMIDITY RETURNS FOR FRI AND SAT. MAX TEMPS WILL GENERALLY BE IN THE
LWR TO MID 80S THRU THE PERIOD. MIN TEMPS WILL RANGE FM THE UPR 50S
TO MID 60S WED AND THU MORNGS...IN THE LWR TO MID 60S FRI
MORNG...AND RANGE THRU THE 60S SAT MORNG.
&&
.AVIATION /14Z SUNDAY THROUGH THURSDAY/...
AREA OF CONVECTION SLIDING SE FM SW PA/NRN WV/NW VA TO CONT
TRACKING ESE THROUGH EARLY MRNG HRS W/ SOME WEAKENING AS IT DOES
SO. PTNTL FOR PCPN AND BRIEF MVFR CIGS/VSBYS...ESP KRIC-KSBY. A
SECOND AREA OF CONVECTION FCST TO EXIT THE MTNS MID/LT MRNG...AND
TRACK OVR THE RGN MIDDAY INTO THIS EVE (ALSO W/ PSBL BRIEF MVFR
CIGS/VSBYS/HVY RA). OTRW...SSW WINDS GUSTING TO 15 KT AND SCT-BKN
CLDS XPCD TDA AS A COLD FRONT APPROACHES THE REGION FROM THE W.
THE FRONT IS XPCD TO CROSS THE REGION ON MONDAY W/ LO PROB FOR
PCPN AND GUSTY MNLY W WNDS (TO 20 KT). MNLY VFR CONDS MON NGT INTO
WED.
NOTE: OBSERVATIONS FROM KSBY ARE NOT READILY AVAILABLE DUE TO A
COMMUNICATIONS PROBLEM. RETURN TO SERVICE IS UNKNOWN AT THIS TIME.
HOWEVER...CURRENT INFORMATION MAY BE OBTAINED BY CALLING INTO THE
ASOS SITE DIRECTLY. AMD NOT SKED WILL BE APPENDED TO THE KSBY TAF
UNTIL FURTHER NOTICE.
&&
.MARINE...
NO HEADLINES XPCD THRU MON. A CDFNT PUSHES APPROACHES THE MID ATLC
REGION TDA...THEN MOVE ACRS THE WTRS AND OFF THE CST LATE TNGT
THROUGH MON NGT. SSW WINDS 10 TO 20 KT THROUGH TNGT. WINDS WILL TURN
TO THE W DURING MON...THEN NW AND N MON NGT INTO TUE MRNG.
WAVES/SEAS LIKELY TO RISE A FOOT OR TWO IN RESPONSE TO INCRSD SPDS
AND DIRECTION CHG TO NNW (MON NGT INTO TUE). GENERALLY NNE WINDS
15 KT OR LESS EXPECTED FOR TUE THRU THU.
&&
.AKQ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
NC...NONE.
VA...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...MPR
NEAR TERM...MPR
SHORT TERM...BMD
LONG TERM...TMG
AVIATION...ALB
MARINE...ALB
AREA FORECAST DISCUSSION
NWS GRAND RAPIDS MI
1145 AM EDT SUN JUL 27 2014
LATEST UPDATE...
MESOSCALE DISCUSSION/UPDATE/MARINE
.MESOSCALE DISCUSSION...
ISSUED AT 1134 AM EDT SUN JUL 27 2014
THINKING THAT THE STRONGER CONVECTION WILL BE UNDERWAY BY 18Z.
ALREADY FAVORABLE PARAMETERS FOR BIGGER HAIL...GOOD CAPE IN THE
-10 TO -30 DEG C LAYER AND FAVORABLE DEEP LAYER SHEAR EXITS. WATER
VAPOR IMAGERY SHOWS THE APPROACHING MID LEVEL WAVE NOW IN
WI...ADVANCING STEADILY EAST SOUTHEAST. INLAND LOCATIONS LIKE MOP
TO LAN TO JXN SEEM MOST VULNERABLE...BUT EVEN GRR AND AZO NOT OUT
OF THE THREAT AT THIS TIME. BY 22Z...THE STRONGEST CONVECTION
SHOULD BE MOVING EAST OF LAN AND JXN.
&&
.SYNOPSIS...
ISSUED AT 328 AM EDT SUN JUL 27 2014
THUNDERSTORMS ARE LIKELY TODAY ACROSS SOUTHWEST LOWER MICHIGAN. A
FEW OF THE STORMS COULD BE STRONG TO SEVERE...ESPECIALLY SOUTHEAST
OF GRAND RAPIDS. TEMPERATURES WILL BE QUITE A BIT COOLER MONDAY AND
STRUGGLE TO REACH 70...WELL BELOW NORMAL FOR LATE JULY. HIGHS MUCH
OF NEXT WEEK WILL BE IN THE 70S.
&&
.UPDATE...
ISSUED AT 1134 AM EDT SUN JUL 27 2014
NOT MAJOR CHANGES TO THE FORECAST. RISK FOR STRONG TO SEVERE
STORMS CONTINUES FOR THE AFTERNOON. WILL KEEP THE HIGHER POPS
GOING GIVEN THE CURRENT DESTABILIZATION AND APPROACHING MID LEVEL
WAVE.
UPDATE ISSUED AT 944 AM EDT SUN JUL 27 2014
DENSE FOG HAS LIFTED ALONG/SOUTH OF I-96 AND HAVE CANCELLED THE
DENSE FOG ADVISORY ISSUED EARLIER. HOWEVER HAVE LEFT THE ADVISORY
UP OVER THE LK MI NEARSHORE AREA FOR NOW AS WEB CAMS AT THE COAST
STILL REVEAL AREAS OF DENSE FOG.
EXTENSIVE STRATUS WILL INHIBIT DESTABILIZATION THIS MORNING BUT IT
SHOULD EVENTUALLY MIX OUT TOWARD NOON. LATEST RAP FCST SNDGS
STILL SHOWING 2000-3000 J/KG OF CAPE DEVELOPING BY 18Z WITH FAT
CAPE PROFILES. THE SIG HAIL PARAMETER FROM SPC MESO PAGE IS
ALREADY 1-1.5 WITH H7-H5 MID LEVEL LAPSE RATES AROUND 7C.
THEREFORE THE GREATEST THREAT AT LEAST INITIALLY EARLY THIS
AFTERNOON WITH DEVELOPING CONVECTION IS LARGE HAIL GREATER THAN
ONE INCH IN DIAMETER.
&&
.SHORT TERM...(TODAY THROUGH TUESDAY)
ISSUED AT 328 AM EDT SUN JUL 27 2014
FORECAST CONCERNS DEAL WITH THE CONVECTIVE THREAT TODAY.
OVERALL...OUR THINKING HASN`T CHANGED MUCH. HOWEVER...THE SPC SLIGHT
RISK HAS BEEN PUSHED SOUTH OUT OF THE CWA. THIS IS LIKELY DUE TO
SLIGHTLY LOWER SHEAR VALUES.
A COLD FRONT IS MOVING THROUGH NORTHWEST WISCONSIN ATTM. A FEW
SUPERCELLS DEVELOPED AND PRODUCED 2 INCH HAIL AS THEY MOVED THROUGH
CENTRAL WISCONSIN. THESE STORMS HAVE DIMINISHED THOUGH AS THEY`VE
OUTRUN THE STRONGER DYNAMICS.
WV IMAGERY SHOWS A WELL DEFINED SHORT WAVE MOVING OVER NORTHERN
MINNESOTA. THIS IS PUSHING THE FRONT SOUTHEAST TOWARD LOWER
MICHIGAN. AHEAD OF THE FRONT DEWPOINTS IN THE MID 60S WILL PROVIDE
PLENTY OF LOW LEVEL MOISTURE TO WORK WITH. LI`S AROUND -6C COUPLED
WITH MLCAPE VALUES AROUND 1500 J/KG WILL AND 0-6KM BULK SHEAR NEAR
40 KTS AND STRONG PVA SHOULD BE MORE THAN ENOUGH TO GENERATE SOME
ORGANIZED STORMS TODAY. FAVORED TIME FRAME IS FROM AROUND 11 AM
THROUGH 3-4 PM. FAVORED AREA IS SOUTHEAST OF GRAND RAPIDS. HIGH
LIKELY AND ABOVE POPS ARE IN THE GRIDS TODAY. CERTAINLY CAN`T RULE
OUT A SEVERE STORM OR TWO. HAIL IS THE MAIN THREAT WITH THE COLD
TEMPS ALOFT COMING IN.
THE COLD FRONT WILL QUICKLY SWEEP THROUGH THE CWA BY THIS EVENING
AND MUCH COOLER AND DRIER AIR WILL MOVE IN FOR MONDAY. HIGHS MOSTLY
IN THE UPPER 60S TO AROUND 70 EXPECTED.
A SECONDARY COLD FRONT WILL DROP SOUTH TUESDAY SO WE INCLUDED CHC
POPS FOR THAT. H5 TEMPS FALL 4C FROM MONDAY THROUGH TUESDAY. SO
LAPSE RATES STEEPEN QUITE A BIT. WOULD EXPECT SOME SMALL HAIL OUT
OF ANY STORMS THAT DEVELOP TUESDAY.
.LONG TERM...(TUESDAY NIGHT THROUGH SATURDAY)
ISSUED AT 328 AM EDT SUN JUL 27 2014
MODELS ARE STILL INDICATING AN UPPER LEVEL TROUGH OVER THE GREAT
LAKES REGION THROUGH THE BULK OF THE LONG TERM PERIOD. THE CORE OF
THE TROUGH WILL BE CENTERED OVER ONTARIO AND QUEBEC...BUT COOLER AIR
WILL SPILL INTO THE AREA. HIGH TEMPERATURES THROUGH THE PERIOD WILL
END UP BEING 5 TO 10 DEGREES BELOW NORMAL. ACTUAL HIGHS WILL RANGE
FROM THE MIDDLE TO UPPER 70S WEDNESDAY THROUGH SATURDAY.
IN TERMS OF SENSIBLE WEATHER...CONTINUED THE FORECAST THEME OF
DIURNAL SHOWERS AND A FEW STORMS. COLD AIR IN THE MID LEVELS
COMBINED WITH JULY SUNSHINE SHOULD RESULT IN AFTERNOON AND EVENING
POP UP SHOWERS AND STORMS. WEDNESDAY AND THURSDAY MAY HAVE A HIGHER
COVERAGE IN PRECIPITATION AS A MORE SUBSTANTIAL VORT LOBE IS
FORECAST TO SWING AROUND THE UPPER LOW...BRUSHING THE LOWER
PENINSULA.
CANNOT RULE OUT SOME SHOWERS AND A FEW STORMS EVEN INTO FRIDAY AND
SATURDAY AFTERNOON/S AS THE TROUGHING REMAINS IN PLACE. NOT A WASH
OUT IN THE LONG TERM BY ANY MEANS...BUT A FLARE UP IN COVERAGE EACH
DAY.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z MONDAY MORNING)
ISSUED AT 748 AM EDT SUN JUL 27 2014
WIDESPREAD LIFR ACROSS THE AREA THIS MORNING. THE STRATUS AND FOG
SHOULD GRADUALLY LIFT THROUGH THE COURSE OF THE NEXT 3-4 HOURS OR
THROUGH 15Z TO 16Z. BY MIDDAY...EXPECTING FAIRLY WIDESPREAD MVFR
CONDITIONS. THE EXPECTATION IS THAT CONDITIONS WILL TRY TO IMPROVE
TO VFR AS WE MOVE THROUGH THE AFTERNOON AND HEAD INTO THE EVENING.
VFR WILL LIKELY BE SHORT LIVED HOWEVER AS MVFR CLOUDS SAG BACK IN
FROM THE NORTH TONIGHT BEHIND A COLD FRONTAL PASSAGE.
SCATTERED SHOWERS THIS MORNING SHOULD TURN INTO SCATTERED
THUNDERSTORMS THIS AFTERNOON. THE TIMING OF MOST PREVALENT STORMS
SHOULD BE BETWEEN 16Z AND 23Z ACROSS THE AREA. A FEW LINGERING
SHOWERS MAY REMAIN THIS EVENING BEFORE DISSIPATING OVERNIGHT.
AT THIS POINT HAVE VCTS IN FOR THIS AFTERNOON AS THE LOCATION OF
THE STORMS IS A LOW CONFIDENCE FORECAST.
&&
.MARINE...
ISSUED AT 1134 AM EDT SUN JUL 27 2014
WEBCAMS AND VISIBILE IMAGERY STILL SHOWED FAIRLY EXTENSIVE FOG ON
THE LAKESHORE. THE ADVISORY FOR FOG WAS STRETCHED INTO THE
AFTERNOON. THE WIND SHIFT AND DRY AIR ADVECTION LATER TODAY WILL
BREAK UP THE FOG.
HIGH POTENTIAL FOR BEACH HAZARDS AND SMALL CRAFT CONDITIONS LATER
TONIGHT INTO MONDAY.
&&
.HYDROLOGY...
ISSUED AT 1207 PM EDT SAT JUL 26 2014
THE MAIN PRECIPITATION THREAT WILL BE SUNDAY AS MOISTURE EDGES UP
INTO THE AREA. PWAT VALUES PUSH BETWEEN 1.0 TO 1.5 INCHES DURING
THE AFTERNOON. THIS MAY RESULT IN LOCALIZED HEAVY RAINFALL IN AND
AROUND THUNDERSTORMS. HOWEVER...AREA AVERAGES ARE MORE LIKELY TO
RANGE FROM ONE-QUARTER TO ONE-HALF AN INCH. PRECIPITATION THEN
SEEMS TO LINGER INTO MONDAY BUT SHOULD NOT BE OF ANY GREAT
SIGNIFICANCE IN THE MONDAY MORNING TIME FRAME.
ASIDE FROM SUNDAYS FOCUS...WE WILL SEE MAINLY DRY CONDITIONS TODAY.
ADDITIONAL CHANCES FOR LIGHT RAIN EXIST AS WE HEAD THROUGH THE NEW
WORK WEEK. NO HIGH END PRECIPITATION EVENTS ARE ANTICIPATED TO AFFECT
THE AREA. RIVERS CONTINUE TO RUN WELL BELOW ACTION STAGE...SO NO
CONCERN FOR RIVER FLOODING AT THIS TIME.
&&
.GRR WATCHES/WARNINGS/ADVISORIES...
MI...BEACH HAZARDS STATEMENT FROM MONDAY MORNING THROUGH MONDAY
EVENING FOR MIZ037-043-050-056-064-071.
LM...SMALL CRAFT ADVISORY FROM 8 PM THIS EVENING TO 6 AM EDT TUESDAY
FOR LMZ844>849.
DENSE FOG ADVISORY UNTIL 2 PM EDT THIS AFTERNOON FOR LMZ844>847.
&&
$$
MESOSCALE...MJS
UPDATE...MJS
SYNOPSIS...93
SHORT TERM...93
LONG TERM...DUKE
AVIATION...DUKE
HYDROLOGY...JAM
MARINE...MJS
AREA FORECAST DISCUSSION
NWS GRAND RAPIDS MI
944 AM EDT SUN JUL 27 2014
LATEST UPDATE...
UPDATE
.SYNOPSIS...
ISSUED AT 328 AM EDT SUN JUL 27 2014
THUNDERSTORMS ARE LIKELY TODAY ACROSS SOUTHWEST LOWER MICHIGAN. A
FEW OF THE STORMS COULD BE STRONG TO SEVERE...ESPECIALLY SOUTHEAST
OF GRAND RAPIDS. TEMPERATURES WILL BE QUITE A BIT COOLER MONDAY AND
STRUGGLE TO REACH 70...WELL BELOW NORMAL FOR LATE JULY. HIGHS MUCH
OF NEXT WEEK WILL BE IN THE 70S.
&&
.UPDATE...
ISSUED AT 944 AM EDT SUN JUL 27 2014
DENSE FOG HAS LIFTED ALONG/SOUTH OF I-96 AND HAVE CANCELLED THE
DENSE FOG ADVISORY ISSUED EARLIER. HOWEVER HAVE LEFT THE ADVISORY
UP OVER THE LK MI NEARSHORE AREA FOR NOW AS WEB CAMS AT THE COAST
STILL REVEAL AREAS OF DENSE FOG.
EXTENSIVE STRATUS WILL INHIBIT DESTABILIZATION THIS MORNING BUT IT
SHOULD EVENTUALLY MIX OUT TOWARD NOON. LATEST RAP FCST SNDGS
STILL SHOWING 2000-3000 J/KG OF CAPE DEVELOPING BY 18Z WITH FAT
CAPE PROFILES. THE SIG HAIL PARAMETER FROM SPC MESO PAGE IS
ALREADY 1-1.5 WITH H7-H5 MID LEVEL LAPSE RATES AROUND 7C.
THEREFORE THE GREATEST THREAT AT LEAST INITIALLY EARLY THIS
AFTERNOON WITH DEVELOPING CONVECTION IS LARGE HAIL GREATER THAN
ONE INCH IN DIAMETER.
&&
.SHORT TERM...(TODAY THROUGH TUESDAY)
ISSUED AT 328 AM EDT SUN JUL 27 2014
FORECAST CONCERNS DEAL WITH THE CONVECTIVE THREAT TODAY.
OVERALL...OUR THINKING HASN`T CHANGED MUCH. HOWEVER...THE SPC SLIGHT
RISK HAS BEEN PUSHED SOUTH OUT OF THE CWA. THIS IS LIKELY DUE TO
SLIGHTLY LOWER SHEAR VALUES.
A COLD FRONT IS MOVING THROUGH NORTHWEST WISCONSIN ATTM. A FEW
SUPERCELLS DEVELOPED AND PRODUCED 2 INCH HAIL AS THEY MOVED THROUGH
CENTRAL WISCONSIN. THESE STORMS HAVE DIMINISHED THOUGH AS THEY`VE
OUTRUN THE STRONGER DYNAMICS.
WV IMAGERY SHOWS A WELL DEFINED SHORT WAVE MOVING OVER NORTHERN
MINNESOTA. THIS IS PUSHING THE FRONT SOUTHEAST TOWARD LOWER
MICHIGAN. AHEAD OF THE FRONT DEWPOINTS IN THE MID 60S WILL PROVIDE
PLENTY OF LOW LEVEL MOISTURE TO WORK WITH. LI`S AROUND -6C COUPLED
WITH MLCAPE VALUES AROUND 1500 J/KG WILL AND 0-6KM BULK SHEAR NEAR
40 KTS AND STRONG PVA SHOULD BE MORE THAN ENOUGH TO GENERATE SOME
ORGANIZED STORMS TODAY. FAVORED TIME FRAME IS FROM AROUND 11 AM
THROUGH 3-4 PM. FAVORED AREA IS SOUTHEAST OF GRAND RAPIDS. HIGH
LIKELY AND ABOVE POPS ARE IN THE GRIDS TODAY. CERTAINLY CAN`T RULE
OUT A SEVERE STORM OR TWO. HAIL IS THE MAIN THREAT WITH THE COLD
TEMPS ALOFT COMING IN.
THE COLD FRONT WILL QUICKLY SWEEP THROUGH THE CWA BY THIS EVENING
AND MUCH COOLER AND DRIER AIR WILL MOVE IN FOR MONDAY. HIGHS MOSTLY
IN THE UPPER 60S TO AROUND 70 EXPECTED.
A SECONDARY COLD FRONT WILL DROP SOUTH TUESDAY SO WE INCLUDED CHC
POPS FOR THAT. H5 TEMPS FALL 4C FROM MONDAY THROUGH TUESDAY. SO
LAPSE RATES STEEPEN QUITE A BIT. WOULD EXPECT SOME SMALL HAIL OUT
OF ANY STORMS THAT DEVELOP TUESDAY.
.LONG TERM...(TUESDAY NIGHT THROUGH SATURDAY)
ISSUED AT 328 AM EDT SUN JUL 27 2014
MODELS ARE STILL INDICATING AN UPPER LEVEL TROUGH OVER THE GREAT
LAKES REGION THROUGH THE BULK OF THE LONG TERM PERIOD. THE CORE OF
THE TROUGH WILL BE CENTERED OVER ONTARIO AND QUEBEC...BUT COOLER AIR
WILL SPILL INTO THE AREA. HIGH TEMPERATURES THROUGH THE PERIOD WILL
END UP BEING 5 TO 10 DEGREES BELOW NORMAL. ACTUAL HIGHS WILL RANGE
FROM THE MIDDLE TO UPPER 70S WEDNESDAY THROUGH SATURDAY.
IN TERMS OF SENSIBLE WEATHER...CONTINUED THE FORECAST THEME OF
DIURNAL SHOWERS AND A FEW STORMS. COLD AIR IN THE MID LEVELS
COMBINED WITH JULY SUNSHINE SHOULD RESULT IN AFTERNOON AND EVENING
POP UP SHOWERS AND STORMS. WEDNESDAY AND THURSDAY MAY HAVE A HIGHER
COVERAGE IN PRECIPITATION AS A MORE SUBSTANTIAL VORT LOBE IS
FORECAST TO SWING AROUND THE UPPER LOW...BRUSHING THE LOWER
PENINSULA.
CANNOT RULE OUT SOME SHOWERS AND A FEW STORMS EVEN INTO FRIDAY AND
SATURDAY AFTERNOON/S AS THE TROUGHING REMAINS IN PLACE. NOT A WASH
OUT IN THE LONG TERM BY ANY MEANS...BUT A FLARE UP IN COVERAGE EACH
DAY.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z MONDAY MORNING)
ISSUED AT 748 AM EDT SUN JUL 27 2014
WIDESPREAD LIFR ACROSS THE AREA THIS MORNING. THE STRATUS AND FOG
SHOULD GRADUALLY LIFT THROUGH THE COURSE OF THE NEXT 3-4 HOURS OR
THROUGH 15Z TO 16Z. BY MIDDAY...EXPECTING FAIRLY WIDESPREAD MVFR
CONDITIONS. THE EXPECTATION IS THAT CONDITIONS WILL TRY TO IMPROVE
TO VFR AS WE MOVE THROUGH THE AFTERNOON AND HEAD INTO THE EVENING.
VFR WILL LIKELY BE SHORT LIVED HOWEVER AS MVFR CLOUDS SAG BACK IN
FROM THE NORTH TONIGHT BEHIND A COLD FRONTAL PASSAGE.
SCATTERED SHOWERS THIS MORNING SHOULD TURN INTO SCATTERED
THUNDERSTORMS THIS AFTERNOON. THE TIMING OF MOST PREVALENT STORMS
SHOULD BE BETWEEN 16Z AND 23Z ACROSS THE AREA. A FEW LINGERING
SHOWERS MAY REMAIN THIS EVENING BEFORE DISSIPATING OVERNIGHT.
AT THIS POINT HAVE VCTS IN FOR THIS AFTERNOON AS THE LOCATION OF
THE STORMS IS A LOW CONFIDENCE FORECAST.
&&
.MARINE...
ISSUED AT 328 AM EDT SUN JUL 27 2014
COLDER AIR WILL MOVE INTO THE REGION TONIGHT AND CONTINUE MONDAY.
THIS SURGE OF COLDER AIR WILL RESULT IN A BIG JUMP IN WAVE HEIGHTS
LATER TODAY AND TONIGHT. WE ISSUED A SCA FOR TONIGHT THROUGH MONDAY
NIGHT TO COVER THIS THREAT AND ALSO A BEACH HAZARDS STATEMENT FOR
MONDAY. THE NORTHWEST WINDS WILL CREATE LONG SHORE AND STRUCTURAL
CURRENTS THAT WILL MAKE SWIMMING HAZARDOUS...ESPECIALLY ON NORTH
SIDES OF PIERS AND BREAKWALLS.
&&
.HYDROLOGY...
ISSUED AT 1207 PM EDT SAT JUL 26 2014
THE MAIN PRECIPITATION THREAT WILL BE SUNDAY AS MOISTURE EDGES UP
INTO THE AREA. PWAT VALUES PUSH BETWEEN 1.0 TO 1.5 INCHES DURING
THE AFTERNOON. THIS MAY RESULT IN LOCALIZED HEAVY RAINFALL IN AND
AROUND THUNDERSTORMS. HOWEVER...AREA AVERAGES ARE MORE LIKELY TO
RANGE FROM ONE-QUARTER TO ONE-HALF AN INCH. PRECIPITATION THEN
SEEMS TO LINGER INTO MONDAY BUT SHOULD NOT BE OF ANY GREAT
SIGNIFICANCE IN THE MONDAY MORNING TIME FRAME.
ASIDE FROM SUNDAYS FOCUS...WE WILL SEE MAINLY DRY CONDITIONS TODAY.
ADDITIONAL CHANCES FOR LIGHT RAIN EXIST AS WE HEAD THROUGH THE NEW
WORK WEEK. NO HIGH END PRECIPITATION EVENTS ARE ANTICIPATED TO AFFECT
THE AREA. RIVERS CONTINUE TO RUN WELL BELOW ACTION STAGE...SO NO
CONCERN FOR RIVER FLOODING AT THIS TIME.
&&
.GRR WATCHES/WARNINGS/ADVISORIES...
MI...BEACH HAZARDS STATEMENT FROM MONDAY MORNING THROUGH MONDAY
EVENING FOR MIZ037-043-050-056-064-071.
LM...SMALL CRAFT ADVISORY FROM 8 PM THIS EVENING TO 6 AM EDT TUESDAY
FOR LMZ844>849.
DENSE FOG ADVISORY UNTIL 11 AM EDT THIS MORNING FOR LMZ844>847.
&&
$$
UPDATE...MEADE
SYNOPSIS...93
SHORT TERM...93
LONG TERM...DUKE
AVIATION...DUKE
HYDROLOGY...JAM
MARINE...93
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
1051 AM EDT SUN JUL 27 2014
.SYNOPSIS...
A SERIES OF LOW PRESSURE SYSTEMS WILL TRACK FROM THE MIDWEST TO
THE EAST COAST, BRINGING INCREASINGLY HUMID AIR TO THE AREA, ALONG
WITH A GOOD CHANCE OF SHOWERS AND THUNDERSTORMS. THE BEST CHANCE
FOR A WIDESPREAD RAIN LOOKS TO BE SUNDAY NIGHT INTO MONDAY. COOLER
AND DRIER WEATHER WILL FOLLOW BEHIND THESE SYSTEMS TUESDAY AND
WEDNESDAY.
&&
.NEAR TERM /UNTIL 8 PM THIS EVENING/...
1045 AM UPDATE...
SHORT WAVE INDUCED CONVECTION HAS MOVED WELL EASTWARD, LEAVING
ISOLATED TO SCATTERED CELLS OVER THE NORTHERN FA. THE ATMOSPHERE
IS IN RECOVERY MODE AT THIS MOMENT, BUT THERE EXIST INTERESTING
SOUNDINGS UPSTREAM SOUNDINGS (12Z AT BUF, PIT, DTX) WHICH SUGGEST
FUTURE UPSTREAM DEVELOPMENT.
NOTABLE ON THE SOUNDINGS ARE AMPLE DRY AIR INTRUSIONS ALOFT AND
OBVIOUS ELVATED MIXED LAYERS. SHEAR/HELICITY VALUES ARE MODEST,
BUT APPEAR SUFFICIENT CONSIDERING STRONG MID LEVEL LAPSE RATES.
SPC MESOSCALE PAGE SHOWS AMPLE MID LEVEL LAPSE RATES (>7C)
UPSTREAM, WHILE SCP VALUES ARE ALREADY IN THE 2-4 RANGE FROM THE
CENTRAL SOUTHERN TIER DOWN TOWARD PIT.
WE LACK AN OBVIOUS TRIGGER FOR THE NEXT SEVERAL HOURS, BUT IF WE
CAN GENERATE CONVECTION AHEAD OF THE NEXT WAVE WITHIN A FEW HOURS
OF PEAK HEATING, STRONG CONVECTION WILL BECOME LIKELY LATE IN THE
DAY. WILL NEED TO WATCH CLOSLEY.
PREVIOUS DISCUSSION...
RADARS SHOW SOME SCATTERED RAIN SHOWERS JUST CLIPPING FAR
NORTHEAST ONEIDA COUNTY AT THIS TIME. THESE SHOWERS WERE EXITING
NORTH CENTRAL NEW YORK AS A WEAKENING UPPER LEVEL WAVE CONTINUES
TO TRACK EASTWARD TOWARD NEW ENGLAND. WATER VAPOR IMAGERY SHOWS A
MUCH MORE SUBSTANTIAL SHORT WAVE PRESENTLY OVER LOWER MICHIGAN AND
LAKE HURON. THIS FEATURE WAS CAPTURED WELL IN THE TROPOPAUSE
PRESSURE FIELDS FOR THE 1.5 PV UNIT ON THE LATEST RAP MODEL. THIS
FEATURE IS PROJECTED TO TRACK INTO CENTRAL NY BY 12Z. RADAR SHOWS
A SWATH OF SHOWERS AND THUNDERSTORMS OVER ONTARIO WITH MUCH LESS
SOUTHWARD. THE HI RES MESOSCALE MODELS ARE HAVING TROUBLE
SIMULATING THE PRESENT RADAR COVERAGE THUS FEEL THEY LIKELY ARE A
BIT SUSPECT. THE HRRR HAS THE BEST HANDLE SO FAR AND LIKE THE
OTHER HI RESOLUTION MODELS BRINGS A SWATH OF SHOWERS AND
THUNDERSTORMS ACRS CENTRAL NY BTWN 9 AND 12Z. SO AS THIS WAVE
PASSES BY LATER THIS MORNING, I WILL HAVE LIKELY POPS IN NC NY AND
TAPER THEM DOWN TO CHC IN NE PA.
AFTER THIS WAVE PASSES AFTER 12Z...CENTRAL NY AND NORTHEAST PA GETS
INTO A LULL WITH MID-LEVEL SUBSIDENCE. MODELS ALL SHOW A NICE
LOW-LEVEL JET FEATURE TRANSPORTING LOW-LEVEL MOISTURE NORTHWARD
DURING THE ERLY MORNING HOURS WITH THE WAVE THAT WILL PASS ACRS C NY
MENTIONED ABV. HENCE DWPTS ABV THE SURFACE WILL BE HIGH ENOUGH TO MIX
DOWN MID TO UPPER 60S DEWPOINTS WITH INSOLATION LATER IN THE MORNING
AND AFTERNOON. SOME LOCALES LIKELY WILL HAVE SFC DEWPOINTS IN THE LOWER 70S.
EVENTUALLY BY AFTERNOON THERE WILL BE ENUF SUNSHINE FOR SIGNIFICANT
INSTABILITY TO DEVELOP. I EXPECT CAPES BETWEEN 1000 AND 2000 J/KG
MIXED LAYER. THE WIND SHEAR INITIALLY THIS AFTERNOON IS FAVORABLE
FOR SEVERE WINDS AND POTENTIAL LARGE HAIL. HOWEVER...THERE IS NO
REAL TRIGGER TO FOCUS ANY CONVECTION THIS AFTERNOON. GIVEN THE
POTENTIAL WE CAN NOT RULE OUT AN ISOLATED TO SCT THUNDERSTORM AND
KEPT POPS IN OUR GRIDS BUT BELIEVE BULK OF ACVTY WILL COME SUNDAY
EVENING AND SUNDAY NIGHT AND NEXT MAJOR WAVE AFFECTS THE REGION.
&&
.SHORT TERM /8 PM THIS EVENING THROUGH TUESDAY NIGHT/...
WATER VAPOR IMAGERY SHOWS AN UNSEASONABLY VIGOUROUS UPPER LEVEL
LOW RAPIDLY MOVING SOUTHEASTWARD INTO NORTHERN MINN AT THIS TIME.
THIS FEATURE WILL CONTINUE TO DROP SOUTHEASTWARD TODAY AND REACH
OHIO BY 03Z MONDAY AND OPEN UP INTO A TROUGH. THIS FEATURE WILL
PROVIDE THE UPPER LEVEL SUPPORT TO FIRE CONVECTION. THE WAVE WILL
WORK ON SIGNIFICANT INSTABILITY OVER THE LWR OHIO VALLEY TO CNTRL
APPLCNS THIS AFTERNOON AND HENCE SPC/S MODERATE RISK FOR SEVERE
WEATHER DOWN THERE. AS THIS UPPER LEVEL WAVE BEGINS TO TRACK E
INTO PA BTWN 3 AND 6Z...THE INSTABILITY WILL BE WEAKER BUT STILL,
GIVEN THE UPPER LEVEL SUPPORT, AND MIXED LAYER CAPES STILL BETWEEN
1000 AND 2000 J/KG IN NE PA AND SC NY...I THINK THERE WILL BE A
BAND OF STRONG TO SEVERE THUNDERSTORMS WORKING NORTHEAST FROM C PA
INTO NE PA AND EVENTUALLY SC NY BEFORE IT WEAKENS AND STATIFORMS
OUT IN C NY BY 6Z. STILL CONCUR WITH SPC SLGHT RISK...ESPECIALLY
FROM SC NY TO NE PA IN THE WFO BGM FORECAST AREA. FARTHER N...BY
THE TIME THE INFLUENCE OF THIS WAVE REACHES NC NY...INSTABILITY
WILL BE LESS AND THE SHEAR WON/T BE AS STRONG. BUT IN ANY EVENT
WILL CONT TO MENTION CHC FOR SVR THUNDERSTORMS IN HWO MAINLY SUN
EVENING AND NOT TAKE NC NY OUT JUST YET.
THEN BETWEEN 6Z-12Z MON THINGS GET INTERESTING. DUE TO THE DIGGING
UPPER LEVEL TROF AND CONVECTION...ALL SYNOPTIC MODELS INDICATE
THAT A LOW-LEVEL CYCLONE WILL DEVELOP FROM NW PA TO NJ. BY 12Z THE
4 MAIN SYNOPTIC MODELS...EURO...CMC...NAM AND GFS ALL DIFFER IN
THE TIMING OF THE SFC LO. THE EURO IS SLOWEST IN BRINGING IT TO SE
NY BY 18Z MON...WITH THE GFS THE FASTEST HAVING THE SFC LO OVER
NH AT THIS TIME. THE OTHER TWO MODELS ARE IN BETWEEN.
IN ANY EVENT...THE DEVELOPMENT OF THIS LOW-LEVEL CYCLONE WILL PUT
A DEFORMATION ZONE WITH SIGNIFICENT FGEN FORCING ON THE NW SIDE OF
IT...WHICH AS PER NAM...GFS...AND CMC HAS A SWATH OF HEAVY RAIN
FOR PORTIONS OF C NY AND NRN PA BTWN 6Z AND 18Z MONDAY. THE EURO
IS FARTHER W WITH THIS AXIS OF HEAVIER PRECIP. THE INTERESTING
ASPECT OF THIS THAT THERE IS A SLOPED LAYER OF FGEN FORCING ON THE
NW SIDE OF THE LOW WITH CONVECTIVE INSTABILITY ALOFT. THIS COULD
MEAN THAT AS THE BAND OF POTENTIALLY STRONG TO SEVERE STORMS THAT WORKS
NORTHEAST ACR NE PA AND SC NY...SLOWS DOWN AND EVENTUALLY BECOMES
A HEAVY RAIN PRODUCER AS IT STRATIFORMS OUT. THE NAM HAS THE
HIGHEST QPF WITH 2.5 TO 3.5 INCHES ACRS C NY. THE OTHER MODELS ARE
TAMER BUT STILL HAVE UP TO 2 INCHES OR MORE. THIS COULD MEAN LOCALLY
THAT RAINFALL WHICH COULD EXCEED THREE OR EVEN FOUR INCHES LOCALLY SO
WILL HAVE TO WATCH OUT FOR THE POTENTIAL FOR FLASH FLOODING SUN
NGT AS WELL. WILL MENTION IN HWO.
FOR MONDAY DURING THE DAY...THE SFC LO PULLS OUT TO THE NE AND THE
RAINFALL STARTS TO WIND DOWN FROM SW-NE LATE IN THE DAY. THE EURO IS
SLOWEST BRINGING THE PRECIP OUT WITH THE NAM AND GFS THE FASTEST.
WILL MAINTAIN LINGERING SHRA MOST OF THE DAY AS PER SURROUNDING
OFFICES GRIDS. WOULDNT BE SURPRISED IF PRECIP ENDS A BIT QUICKER
THAN CURRENTLY ADVERVISED MON PM THOUGH.
FOR MON NGT...ONLY THE EURO HAS LINGERING PRECIP FOR THE CATSKILLS
TO THE UPPER MOHAWK VALLEY. REST OF MODELS ARE BASICALLY DRY. FOR
NOW WILL GO WITH EURO/S AND SURROUNDING OFFICES IDEA OF SLGHT CHC
TO CHC SHRA MON EVE...THEN END PRECIP AFTER MIDNIGHT INTO ERLY
TUESDAY.
FOR TUE... HAVE POP UP SHRA GIVEN THE COLDER AIR ALOFT. TUE NGT
WILL SEE HIGH PRESSURE AND FAIR WEATHER. A FEW LINGERING SHRA
STILL POSSIBLE IN THE FINGER LAKES REGION CLOSER TO THE NEXT WAVE.
&&
.LONG TERM /WEDNESDAY THROUGH SATURDAY/...
430 AM UPDATE...NO SIGNIFICANT CHANGES TO EXTENDED JUST REFRESHED
WITH LATEST WPC GUIDANCE. UPPER LEVEL TROF AXIS WILL REMAIN JUST
WEST OF AREA THROUGHOUT PERIOD. EACH DAY WILL CONTINUE TO CARRY
SLIGHT CHC/CHC POPS DURING THE AFTERNOON FOR DIURNAL CONVECTION
UNDER AN EVER PERSISTENT EASTERN TROF. TEMPS WILL RUN SEVERAL
DEGREES BELOW SEASONAL LEVELS.
145 PM UPDATE...
HIPRES AT THE SFC WL BE OVR THE CWA AT THE START OF THE LONG TERM
PD. HWVR FLOW ALOFT WL BE DOMINATED BY A L/WV TROF. THIS WL KEEP
SLGT CHCS FOR AFTN SHRA/TSRA THRU THE END OF THE WEEK AND GIVE
CREDENCE TO THE WORDS "DIRTY HIGH." HV BASICALLY FOLLOWED WPC
GUIDANCE WITH 20 POPS EACH AFTN ALONG WITH NR NORMAL TEMPS, WITH
HIGHS ARND 80 AND LOWS IN THE 50S EXPECTED EACH PERIOD.
&&
.AVIATION /14Z SUNDAY THROUGH THURSDAY/...
LINE OF CONVECTION MOVING THROUGH AREA AT 11Z WILL BE EAST OF
TERMINALS BY 12Z BUT LINGERING MVFR CIGS ARE LIKELY THROUGH
MID/LATE MORNING. LATER THIS MORNING VFR CONDITIONS WITH JUST
SCT/BKN FAIR WX CU AND BKN CI EXPECTED. ISOLATED CONVECTION IS
POSSIBLE THIS AFTERNOON BUT NOT INCLUDED DUE TO VERY LIMITED AREAL
COVERAGE. THIS EVENING A DEEP UPPER LEVEL TROF AND ASSOCIATED SFC
LOW WILL BRING WIDESPREAD MODERATE SHOWERS TO THE TERMINALS.
ACROSS THE SOUTHERN TERMINALS BEGAN THIS ACTIVITY AROUND 00Z AND
AT 06Z AT KSYR/KRME.
S/SW WINDS EARLY THIS MORNING AROUND 5-8 KNOTS EXCEPT SE AT KRME.
AFTER MID MORNING SOUTHWEST WINDS AROUND 10 KNOTS BECOMING LIGHT
AND VARIABLE OVERNIGHT.
OUTLOOK...
MON-MON NGT...POTENTIAL RESTRICTIONS IN SHRA/TSRA.
TUE-THU...RESTRICTIONS POSSIBLE EACH AFTERNOON IN SHRA.
&&
.BGM WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NY...NONE.
&&
$$
SYNOPSIS...DJN
NEAR TERM...DJN/DJP
SHORT TERM...DJN
LONG TERM...PVN/RRM
AVIATION...RRM
AREA FORECAST DISCUSSION
NWS BURLINGTON VT
1021 AM EDT SUN JUL 27 2014
.SYNOPSIS...
ACTIVE PERIOD OF WEATHER IS EXPECTED ACROSS THE NORTH COUNTRY
TODAY INTO MONDAY. INITIAL AREA OF SHOWERS AND THUNDERSTORMS WILL
MOVE ACROSS THE REGION THROUGH THE MORNING HOURS...WITH RE-
DEVELOPMENT OF THUNDERSTORMS...SOME STRONG...DURING THE AFTERNOON.
A POTENT MID-SUMMER LOW WILL TRACK ACROSS THE NORTH COUNTRY ON
MONDAY WITH A WETTING RAINFALL TO THE REGION WITH POTENTIAL FOR
THUNDERSTORMS ACROSS EASTERN VERMONT. GRADUALLY IMPROVING
CONDITIONS TUESDAY INTO MIDWEEK...WITH HIGH TEMPERATURES BEING A
FEW DEGREES BELOW NORMAL THROUGH MIDWEEK.
&&
.NEAR TERM /UNTIL 7 PM THIS EVENING/...
AS OF 1019 AM EDT SUNDAY...CRNT RADAR SHOWING A BAND OF MODERATE
RAIN WITH EMBEDDED RUMBLES OF THUNDER ACRS CENTRAL/EASTERN VT
ATTM. HAVE UPDATED TO TRIM BACK POPS ACRS THE CPV/DACKS TO CHC.
CONTINUED TO MENTION HIGH CAT POPS FOR PRECIP ACRS CENTRAL/EASTERN
VT...BUT THIS WL CLR OUR CWA BY 16Z TODAY. RAINFALL AMOUNTS HAVE
RANGED BTWN 0.10 AND 0.50 ASSOCIATED WITH THIS FEATURE...WITH 0.30
FALLING AT BTV THRU 10 AM. NEXT FCST CHALLENGE WL BE POTENTIAL FOR
ADDITIONAL ACTIVITY THIS AFTN/EVENING. VIS SATL PIC SHOWS A FEW
BREAKS ACRS THE SLV...WHICH WL SPREAD EAST INTO THE CPV/VT BY
EARLY THIS AFTN...ASSOCIATED WITH SUBSIDENCE BEHIND S/W ENERGY.
WATER VAPOR SHOWS ANOTHER WEAK 5H VORT JUST NORTH OF LAKE
ONTARIO...WHICH WL PASS ALONG OUR CENTRAL/NORTHERN CWA BTWN 17Z-
22Z TODAY. THINKING THIS ENERGY ALOFT...COMBINED WITH SOME SFC
HEATING WL RESULT IN WIDELY SCATTERED SHOWERS/STORMS THIS AFTN.
THE LIMITED INSTABILITY AND ULVL FORCING WL KEEP POPS IN THE 30 TO
40% RANGE THIS AFTN. IF ENOUGH INSTABILITY DEVELOPS ACRS THE
CPV...FROM SFC HEATING...A FEW STRONGER STORMS COULD BE POSSIBLE.
LATEST HRRR AND BTV4KM HINT AT THIS POTENTIAL WITH SFC BASED CAPE
VALUES AROUND 1500 J/KG AND DEEP LAYER SHEAR VALUES AROUND 30 TO
35 KNOTS. THESE SOLUTIONS SUPPORT PULSE LIKE STORMS...WITH NO REAL
ORGANIZATION. TEMPS WITH CLOUDS AND PRECIP THIS MORNING WL SLOWLY
CLIMB INTO THE LOWER 70S (MTNS) TO LOWER 80S (SLV/CPV) BY EARLY
THIS AFTN...ESPECIALLY IF A FEW BREAKS IN THE OVERCAST CAN
DEVELOP.
PREVIOUS NEAR-TERM DISCUSSION ISSUED AT 437 AM EDT SUNDAY FOLLOWS...
ONGOING LINE OF HEAVIER SHOWERS AND THUNDERSTORMS NOW ENTERING THE
ST. LAWRENCE VALLEY EARLY THIS MORNING. THIS ACTIVITY TIED TO AN
INITIAL SHORTWAVE MOVING INTO EASTERN VERMONT PER WV IMAGERY AND
WEAK INSTABILITY ALOFT (SHOWALTERS -1 TO -2). LIGHTER SHOWERS
ACROSS WESTERN HALF OF VERMONT. EXPECT THE SOLID LINE OF HEAVIER
SHOWERS/THUNDERSTORMS TO MOVE ACROSS THE GREENS AND INTO EASTERN
VERMONT THROUGH THE MORNING/EARLY AFTN HOURS. I`VE SHOWN
RELATIVELY HIGH POP (LIKELY TO LOW CATEGORICAL) TO COVER THIS
ONGOING ACTIVITY THROUGH THE MORNING.
FOCUS FOR THE AFTN THEN SHIFTS TOWARDS POTENTIAL FOR RE-DEVELOPING
CONVECTION AND ITS AREAL COVERAGE. FEEL THAT SOME CLEARING IN THE
WAKE OF MORNING SHOWERS WILL ALLOW FOR SOME DESTABILIZATION. I
DON`T THINK THE DEGREE OF INSTABILITY WILL BE QUITE AS HIGH AS WHAT
THE 4-KM NAM OR WRF BTV-4 IS SHOWING (NEAR 2000 J/KG CAPE)...BUT
VALUES AROUND HALF THAT SEEM REASONABLE WITH BREAKS IN THE CLOUDS
AND MID-LEVEL LAPSE RATES OF AROUND 6C/KM. WIND FIELDS ALSO
STRENGTHEN TO PRODUCE 0-6 KM BULK SHEAR MAGNITUDES OF 30-35 KTS.
HOWEVER BY AFTN THE NORTH COUNTRY WILL BE IN BETWEEN THE DEPARTING
SHORTWAVE AND A MORE POTENT SHORTWAVE TROUGH DIVING SOUTHWARD
TOWARD THE CENTRAL APPALACHIANS...IN MID-LEVEL SUBSIDENT/WEAK
HEIGHT RISE REGIME. THAT SHOULD HELP TO SUPPRESS OR KEEP A MORE
ISOLATED TO WIDELY SCATTERED COVERAGE TO ANY STORMS THAT CAN
DEVELOP LATER THIS AFTERNOON. I THOUGHT ABOUT INTRODUCING ENHANCED
WORDING FOR GUSTY WINDS AND SMALL HAIL BUT OVERALL LIMITED AREAL
COVERAGE SUGGESTED AGAINST DOING SO. IT`S ALSO DIFFICULT TO
PINPOINT A FAVORED AREA FOR STRONGER STORMS TODAY...BUT WOULD
THINK EASTERN VERMONT WOULD HAVE A TOUGHER TIME CLEARING AND LOWER
INSTABILITY THERE. I WILL MENTION POTENTIAL FOR STRONGER STORMS IN
THE HWO HOWEVER. OVERALL QPF TODAY GENERALLY A QUARTER TO AS MUCH
AS A HALF-INCH (LOCALLY HIGHER IN THUNDERSTORM DOWNPOURS).
HIGHS SHOULD TOP OUT IN THE 70S TO A SPOT 80 TODAY...GENERALLY
COOLEST ACROSS THE HIGH TERRAIN AND IN EASTERN VERMONT WHERE
SHOWERS/STORMS WILL TAKE LONGER TO CLEAR (I.E. LESS TIME FOR AFTN
BREAKS IN CLOUDS).
&&
.SHORT TERM /7 PM THIS EVENING THROUGH TUESDAY/...
AS OF 437 AM EDT SUNDAY...ACTIVE PERIOD OF WEATHER THEN CONTINUES
LATER SUNDAY NIGHT AND ESPECIALLY ON MONDAY. MORE GRADUAL
IMPROVEMENT FOR TUESDAY BUT STILL GENERALLY UNSETTLED WITH THE
NORTH COUNTRY UNDER A WELL-ADVERTISED 500 MB TROUGH.
TONIGHT: STILL CAN`T RULE OUT AN ISOLATED STRONGER STORM EARLY
EVENING BUT ALREADY LIMITED INSTABILITY WILL BECOME EVEN MORE SO BY
DARK. THE STRONG...POSITIVELY TILTED SHORTWAVE TROUGH ASSUMES A
NEGATIVE TILT BY 12Z MONDAY AND INDUCES SFC LOW DEVELOPMENT NEAR
CENTRAL PA LATER TONIGHT. THERE`S SOME QUESTION MARKS AS TO THIS
LOW`S EXACT TRACK ESPECIALLY IN LIGHT OF POTENTIAL MASS FIELD
CHANGES GIVEN A POTENTIAL SEVERE WEATHER EVENT IN THE MID-ATLANTIC
/APPALACHIANS TODAY. THERE APPEARS TO BE BETTER AGREEMENT ON A MORE
INTERIOR TRACK (LOW ROUGHLY CENTERED OVER THE HUDSON VALLEY REGION
BY 12Z MONDAY) - AND THERE ARE GOOD SIGNALS IN HIGH RES MODELS OF A
BAND OF MODERATE RAIN ON THE NORTHWEST PERIPHERY OF SFC LOW`S
TRACK. THAT BAND OF MODERATE RAIN LOOKS TO OVERSPREAD SOUTHERN
VERMONT INTO THE ADIRONDACKS THROUGH 12Z MONDAY. INITIALLY KEPT
POPS AROUND CHANCE CATEGORY BUT BEGIN TO TREND UPWARD AFTER
MIDNIGHT TO LIKELY/LOW CATEGORICAL BY THE PRE-DAWN HOURS. LOWS
UNLIKELY TO FALL MUCH UNDER OVERCAST SKIES...UPPER 50S TO MID 60S
GENERALLY A DEGREE OR TWO WARMER THAN MAV OR MET MOS GUIDANCE.
MONDAY & MONDAY NIGHT: SFC LOW THEN TRACKS UP THE CHAMPLAIN
VALLEY/GREEN MOUNTAINS THROUGH 00Z TUESDAY...500 MB TROUGH ALSO
PIVOTS NORTHWARD BUT APPEARS TO CLOSE OFF BY MONDAY EVENING. WITH
THAT EXPECTED LOW TRACK...IT LEAVES CENTRAL/EASTERN VERMONT IN THE
WARM SECTOR. FAVORABLE WIND SHEAR PARAMETERS FOR STRONG
THUNDERSTORMS IF GREATER INSTABILITY CAN BE REALIZED (GENERALLY IS
HIGHEST IN THE 00Z GFS) IN THIS CORRIDOR. NORTHWEST OF THE LOW
TRACK...MORE STRATIFORM MODERATE RAIN WILL PIVOT NORTH-NORTHEASTWARD
ACROSS NORTHERN NY AND THE NORTHERN CHAMPLAIN VALLEY. I`VE INDICATED
CHANCE THUNDER FOR CENTRAL AND EASTERN VERMONT IN PROGGED WARM
SECTOR...BUT HAVE OTHERWISE KEPT THUNDER OUT ELSEWHERE WHERE IT`S
LIKELY TO BE MORE RAIN-COOLED/STABLE. CATEGORICAL POPS OFFERED
MONDAY WITH GRADUAL TAPER TO HIGH CHANCE/LIKELY THROUGH MONDAY
EVENING. TEMPS ARE TRICKY/DEPENDENT ON LOW TRACK...BUT LIKELY TO BE
BELOW NORMAL AND CLOSER TO NORMAL IF WARM SECTOR CAN GET
ESTABLISHED. HIGHS IN NORTHERN NY MAY STRUGGLE TO REACH 70 DEGREES
IN A CLOUDY/RAINY DAY...AND CLOSER TO THE MID/UPPER 70S IN CENTRAL
AND EASTERN VERMONT. QPF MONDAY RANGES FROM LESS THAN A HALF-INCH
FOR THE SAINT LAWRENCE VALLEY... .75-1" FOR MUCH OF VERMONT TO JUST
A TICK OVER AN INCH FOR THE ADIRONDACKS. NOT ANTICIPATING ANY HYDRO
ISSUES FROM THIS AMOUNT OF RAIN GIVEN HOW DRY IT HAS BEEN.
TUESDAY: UPPER TROUGH EXITS WITH STILL SOME LINGERING SHOWERS
PARTICULARLY ACROSS HIGHER TERRAIN. NORTHWEST FLOW...MDT COLD
ADVECTION (850 TEMPS DURING TUESDAY PLUNGE TO +6 TO +8C) AND PARTLY
CLOUDY SKIES PRODUCES BELOW NORMAL HIGHS IN THE 60S TO THE LOWER 70S.
&&
.LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/...
AS OF 421 AM EDT SUNDAY...
A SLOW WARMING TREND TO NEAR NORMAL TEMPERATURES IS EXPECTED BY THE
END OF THE WEEK WITH THE HIGHEST CHANCE OF SHOWERS AND THUNDERSTORMS
ON THURSDAY.
MODELS IN GOOD AGREEMENT THAT A DEEP LARGE SCALE TROUGH WILL
REMAIN OVER THE EASTERN US CENTERED NEAR 80 DEG W WITH A RIDGE OVER
THE INTER-MOUNTAIN WEST THROUGHOUT THE PERIOD...THOUGH WEAKENING
WITH RISING HEIGHTS.
THOUGH A SHOWER CAN`T BE COMPLETELY RULED OUT ANY AFTERNOON DURING THIS
PERIOD WITH THE UPPER TROUGH JUST OFF TO THE WEST...THE BEST
CHANCE FOR SEEING SHOWERS AND THUNDERSTORMS WILL BE THURSDAY
AFTERNOON AS A SHORT WAVE WITH COLD AIR ALOFT SWINGS ACROSS THE
AREA WITH SOME INSTABILITY AND SOME QG FORCING.
THE UPPER TROUGH WEAKENS BUT REMAINS IN PLACE FRIDAY INTO THE
WEEKEND BUT RETROGRADES A FEW DEGREES WESTWARD IN RESPONSE TO A
BUILDING ATLANTIC RIDGE ALOFT, RISING HEIGHTS OVER THE EAST COAST
WITH A BERMUDA HIGH STRENGTHENING AT THE SURFACE...WHICH IS FAIRLY
TYPICAL FOR LATE SUMMER. SOME SMALL CHANCE OF SHOWERS AND
THUNDERSTORMS WILL CONTINUE EACH DAY AS AREA REMAINS LOCKED INTO THE
EASTERN SIDE OF THE UPPER TROF.
SLIGHTLY BELOW NORMAL MAX TEMPS ARE EXPECTED WEDNESDAY WITH PARTLY
SUNNY SKIES. HIGHS TEMPS MAINLY IN THE 70S WITH 850 TEMPS ONLY
AROUND 8-10C.
850 MB TEMPS WARM A COUPLE DEGREES EACH DAY SO THAT BY THURSDAY
THROUGH SATURDAY SHOULD BE 12-14C. WITH PARTIAL SUN UNDER DIURNAL
CUMULUS CLOUDS EXPECT HIGHS MODERATING TO NEAR NORMAL -
UPPER 70S LOWER 80S.
&&
.AVIATION /14Z SUNDAY THROUGH THURSDAY/...
THROUGH 06Z MONDAY..MVFR LCL IFR 12-16Z THIS MORNING WITH SHOWERS
AND THUNDERSTORMS AS A WEAK WARM FRONT PUSHES THROUGH THE REGION.
CHANCE OF SHOWERS ARE NEAR 80 PERCENT THROUGH ABOUT 16Z TODAY THEN
DECREASE.
CHANCES OF THUNDER INCREASING ESPECIALLY PBG BTV RUT MPV MOVING
WEST TO EAST 12-16Z.
VISIBILITIES EXPECTED TO REMAIN MAINLY VFR...EXCEPT SOME BRIEF
REDUCTIONS TO MVFR/IFR POSSIBLE IN ANY HEAVIER SHOWERS OR ISOLATED
THUNDERSTORMS.
PERIODS OF MVFR ARE LIKELY ON BACK SIDE OF RAIN SHOWERS...LASTING
UNTIL LATE MORNING WHEN SHOWER THREAT DECREASES. CEILINGS LIFT
BACK TO VFR THIS AFTERNOON.
ISOLATED THUNDERSTORM DEVELOPMENT POSSIBLE AGAIN THIS AFTERNOON/EVENING
AHEAD OF A SLOW SOUTHWARD MOVING COLD FRONT IN CANADA BUT POBABILITIES
ONLY 20-30 PERCENT SO HAVE LEFT OUT ALL BUT SLK WHERE TERRAIN MAY
HELP.
SHOWER AND THUNDER CHANCES DROP THIS EVENING UNDER VFR CONDITIONS.
COULD BE SOME FG/BR CHANCES LATER TONIGHT IF CLEARING SKIES AND
LIGHT WINDS PREVAIL AS FRONTAL SYSTEM STALLS TO OUR NORTH WHEN 09-12Z
MORE SHOWERS AND POSSIBLE THUNDER RETURN ALONG WITH A MVFR/IFR.
SOUTH/SOUTHWEST WINDS 5 TO 10 KNOTS TODAY. SOME GUSTS TO 20 KNOTS
POSSIBLE.
OUTLOOK 12Z MONDAY THROUGH THURSDAY...
12Z MON - 12Z TUE...PERIODS OF MVFR IN RAIN AND ISOLATED
THUNDERSTORMS. LOCAL IFR POSSIBLE IN HEAVIER RAIN.
12Z TUE - 12Z THU...TRENDING VFR. POSSIBLE IFR/LOWER VISIBILITY IN
OVERNIGHT FOG/MIST MPV AND SLK.
12Z THU ONWARD...MAINLY VFR ALTHOUGH BRIEF PERIODS OF MVFR
POSSIBLE IN SCATTERED SHOWERS...MAINLY SLK/MSS.
&&
.MARINE...
AS OF 550 AM EDT SUNDAY...A LAKE THUNDERSTORM ADVISORY IS NOW IN
EFFECT FOR LAKE CHAMPLAIN. A LINE OF THUNDERSTORMS HAS DEVELOPED
OVERNIGHT AND NOW EXTENDS FROM ST. LAWRENCE COUNTY TO THE EASTERN
SHORE OF LAKE ONTARIO. WHILE THERE IS NO IMMEDIATE THREAT OF
LIGHTNING ON LAKE CHAMPLAIN...EXPECT THESE STORMS TO APPROACH LAKE
CHAMPLAIN BY MID-MORNING. BOATERS AND OTHERS NEAR THE LAKE SHOULD
BE PREPARED TO SEEK SAFE HARBOR AS THESE STORMS MOVE
THROUGH...WITH OCCASIONAL TO FREQUENT LIGHTNING...HEAVY DOWNPOURS
PRODUCING BRIEFLY LOWERED VISIBILITY...AND ROUGH SEAS.
ADDITIONAL THUNDERSTORMS MAY DEVELOP AGAIN LATER THIS AFTERNOON.
&&
.BTV WATCHES/WARNINGS/ADVISORIES...
VT...NONE.
NY...NONE.
&&
$$
SYNOPSIS...LOCONTO
NEAR TERM...TABER/LOCONTO
SHORT TERM...LOCONTO
LONG TERM...SISSON
AVIATION...SISSON
MARINE...LOCONTO
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
652 AM EDT SUN JUL 27 2014
.SYNOPSIS...
A SERIES OF LOW PRESSURE SYSTEMS WILL TRACK FROM THE MIDWEST TO
THE EAST COAST THROUGH MONDAY BRINGING INCREASINGLY HUMID AIR TO
THE AREA ALONG WITH A GOOD CHANCE OF SHOWERS AND THUNDERSTORMS.
THE BEST CHANCE FOR A WIDESPREAD RAIN LOOKS TO BE SUNDAY NIGHT
INTO MONDAY. COOLER AND DRYER WEATHER WILL FOLLOW BEHIND THESE
SYSTEMS TUESDAY AND WEDNESDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
RADARS SHOW SOME SCATTERED RAIN SHOWERS JUST CLIPPING FAR NORTHEAST
ONEIDA COUNTY AT THIS TIME. THESE SHOWERS WERE EXITING NORTH CENTRAL
NEW YORK AS A WEAKENING UPPER LEVEL WAVE CONTINUES TO TRACK EASTWARD
TOWARD NEW ENGLAND. WATER VAPOR IMAGERY SHOWS A MUCH MORE SUBSTANTIAL
SHORT WAVE PRESENTLY OVER LOWER MICHIGAN AND LAKE HURON. THIS
FEATURE WAS CAPTURED WELL IN THE TROPOPAUSE PRESSURE FIELDS FOR THE
1.5 PV UNIT ON THE LATEST RAP MODEL. THIS FEATURE IS PROJECTED TO
TRACK INTO CENTRAL NY BY 12Z. RADAR SHOWS A SWATH OF SHOWERS AND
THUNDERSTORMS OVER ONTARIO WITH MUCH LESS SOUTHWARD. THE HI RES
MESOSCALE MODELS ARE HAVING TROUBLE SIMULATING THE PRESENT RADAR
COVERAGE THUS FEEL THEY LIKELY ARE A BIT SUSPECT. THE HRRR HAS THE
BEST HANDLE SO FAR AND LIKE THE OTHER HI RESOLUTION MODELS BRINGS A
SWATH OF SHOWERS AND THUNDERSTORMS ACRS CENTRAL NY BTWN 9 AND 12Z.
SO AS THIS WAVE PASSES BY LATER THIS MORNING, I WILL HAVE LIKELY
POPS IN NC NY AND TAPER THEM DOWN TO CHC IN NE PA.
AFTER THIS WAVE PASSES AFTER 12Z...CENTRAL NY AND NORTHEAST PA GETS
INTO A LULL WITH MID-LEVEL SUBSIDENCE. MODELS ALL SHOW A NICE
LOW-LEVEL JET FEATURE TRANSPORTING LOW-LEVEL MOISTURE NORTHWARD
DURING THE ERLY MORNING HOURS WITH THE WAVE THAT WILL PASS ACRS C NY
MENTIONED ABV. HENCE DWPTS ABV THE SURFACE WILL BE HIGH ENOUGH TO MIX
DOWN MID TO UPPER 60S DEWPOINTS WITH INSOLATION LATER IN THE MORNING
AND AFTERNOON. SOME LOCALES LIKELY WILL HAVE SFC DEWPOINTS IN THE LOWER 70S.
EVENTUALLY BY AFTERNOON THERE WILL BE ENUF SUNSHINE FOR SIGNIFICANT
INSTABILITY TO DEVELOP. I EXPECT CAPES BETWEEN 1000 AND 2000 J/KG
MIXED LAYER. THE WIND SHEAR INITIALLY THIS AFTERNOON IS FAVORABLE
FOR SEVERE WINDS AND POTENTIAL LARGE HAIL. HOWEVER...THERE IS NO
REAL TRIGGER TO FOCUS ANY CONVECTION THIS AFTERNOON. GIVEN THE
POTENTIAL WE CAN NOT RULE OUT AN ISOLATED TO SCT THUNDERSTORM AND
KEPT POPS IN OUR GRIDS BUT BELIEVE BULK OF ACVTY WILL COME SUNDAY
EVENING AND SUNDAY NIGHT AND NEXT MAJOR WAVE AFFECTS THE REGION.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH TUESDAY NIGHT/...
WATER VAPOR IMAGERY SHOWS AN UNSEASONABLY VIGOUROUS UPPER LEVEL
LOW RAPIDLY MOVING SOUTHEASTWARD INTO NORTHERN MINN AT THIS TIME.
THIS FEATURE WILL CONTINUE TO DROP SOUTHEASTWARD TODAY AND REACH
OHIO BY 03Z MONDAY AND OPEN UP INTO A TROUGH. THIS FEATURE WILL
PROVIDE THE UPPER LEVEL SUPPORT TO FIRE CONVECTION. THE WAVE WILL
WORK ON SIGNIFICANT INSTABILITY OVER THE LWR OHIO VALLEY TO CNTRL
APPLCNS THIS AFTERNOON AND HENCE SPC/S MODERATE RISK FOR SEVERE
WEATHER DOWN THERE. AS THIS UPPER LEVEL WAVE BEGINS TO TRACK E
INTO PA BTWN 3 AND 6Z...THE INSTABILITY WILL BE WEAKER BUT STILL,
GIVEN THE UPPER LEVEL SUPPORT, AND MIXED LAYER CAPES STILL BETWEEN
1000 AND 2000 J/KG IN NE PA AND SC NY...I THINK THERE WILL BE A
BAND OF STRONG TO SEVERE THUNDERSTORMS WORKING NORTHEAST FROM C PA
INTO NE PA AND EVENTUALLY SC NY BEFORE IT WEAKENS AND STATIFORMS
OUT IN C NY BY 6Z. STILL CONCUR WITH SPC SLGHT RISK...ESPECIALLY
FROM SC NY TO NE PA IN THE WFO BGM FORECAST AREA. FARTHER N...BY
THE TIME THE INFLUENCE OF THIS WAVE REACHES NC NY...INSTABILITY
WILL BE LESS AND THE SHEAR WON/T BE AS STRONG. BUT IN ANY EVENT
WILL CONT TO MENTION CHC FOR SVR THUNDERSTORMS IN HWO MAINLY SUN
EVENING AND NOT TAKE NC NY OUT JUST YET.
THEN BETWEEN 6Z-12Z MON THINGS GET INTERESTING. DUE TO THE DIGGING
UPPER LEVEL TROF AND CONVECTION...ALL SYNOPTIC MODELS INDICATE
THAT A LOW-LEVEL CYCLONE WILL DEVELOP FROM NW PA TO NJ. BY 12Z THE
4 MAIN SYNOPTIC MODELS...EURO...CMC...NAM AND GFS ALL DIFFER IN
THE TIMING OF THE SFC LO. THE EURO IS SLOWEST IN BRINGING IT TO SE
NY BY 18Z MON...WITH THE GFS THE FASTEST HAVING THE SFC LO OVER
NH AT THIS TIME. THE OTHER TWO MODELS ARE IN BETWEEN.
IN ANY EVENT...THE DEVELOPMENT OF THIS LOW-LEVEL CYCLONE WILL PUT
A DEFORMATION ZONE WITH SIGNIFICENT FGEN FORCING ON THE NW SIDE OF
IT...WHICH AS PER NAM...GFS...AND CMC HAS A SWATH OF HEAVY RAIN
FOR PORTIONS OF C NY AND NRN PA BTWN 6Z AND 18Z MONDAY. THE EURO
IS FARTHER W WITH THIS AXIS OF HEAVIER PRECIP. THE INTERESTING
ASPECT OF THIS THAT THERE IS A SLOPED LAYER OF FGEN FORCING ON THE
NW SIDE OF THE LOW WITH CONVECTIVE INSTABILITY ALOFT. THIS COULD
MEAN THAT AS THE BAND OF POTENTIALLY STRONG TO SEVERE STORMS THAT WORKS
NORTHEAST ACR NE PA AND SC NY...SLOWS DOWN AND EVENTUALLY BECOMES
A HEAVY RAIN PRODUCER AS IT STRATIFORMS OUT. THE NAM HAS THE
HIGHEST QPF WITH 2.5 TO 3.5 INCHES ACRS C NY. THE OTHER MODELS ARE
TAMER BUT STILL HAVE UP TO 2 INCHES OR MORE. THIS COULD MEAN LOCALLY
THAT RAINFALL WHICH COULD EXCEED THREE OR EVEN FOUR INCHES LOCALLY SO
WILL HAVE TO WATCH OUT FOR THE POTENTIAL FOR FLASH FLOODING SUN
NGT AS WELL. WILL MENTION IN HWO.
FOR MONDAY DURING THE DAY...THE SFC LO PULLS OUT TO THE NE AND THE
RAINFALL STARTS TO WIND DOWN FROM SW-NE LATE IN THE DAY. THE EURO IS
SLOWEST BRINGING THE PRECIP OUT WITH THE NAM AND GFS THE FASTEST.
WILL MAINTAIN LINGERING SHRA MOST OF THE DAY AS PER SURROUNDING
OFFICES GRIDS. WOULDNT BE SURPRISED IF PRECIP ENDS A BIT QUICKER
THAN CURRENTLY ADVERVISED MON PM THOUGH.
FOR MON NGT...ONLY THE EURO HAS LINGERING PRECIP FOR THE CATSKILLS
TO THE UPPER MOHAWK VALLEY. REST OF MODELS ARE BASICALLY DRY. FOR
NOW WILL GO WITH EURO/S AND SURROUNDING OFFICES IDEA OF SLGHT CHC
TO CHC SHRA MON EVE...THEN END PRECIP AFTER MIDNIGHT INTO ERLY
TUESDAY.
FOR TUE... HAVE POP UP SHRA GIVEN THE COLDER AIR ALOFT. TUE NGT
WILL SEE HIGH PRESSURE AND FAIR WEATHER. A FEW LINGERING SHRA
STILL POSSIBLE IN THE FINGER LAKES REGION CLOSER TO THE NEXT WAVE.
&&
.LONG TERM /WEDNESDAY THROUGH SATURDAY/...
430 AM UPDATE...NO SIGNIFICANT CHANGES TO EXTENDED JUST REFRESHED
WITH LATEST WPC GUIDANCE. UPPER LEVEL TROF AXIS WILL REMAIN JUST
WEST OF AREA THROUGHOUT PERIOD. EACH DAY WILL CONTINUE TO CARRY
SLIGHT CHC/CHC POPS DURING THE AFTERNOON FOR DIURNAL CONVECTION
UNDER AN EVER PERSISTENT EASTERN TROF. TEMPS WILL RUN SEVERAL
DEGREES BELOW SEASONAL LEVELS.
145 PM UPDATE...
HIPRES AT THE SFC WL BE OVR THE CWA AT THE START OF THE LONG TERM
PD. HWVR FLOW ALOFT WL BE DOMINATED BY A L/WV TROF. THIS WL KEEP
SLGT CHCS FOR AFTN SHRA/TSRA THRU THE END OF THE WEEK AND GIVE
CREDENCE TO THE WORDS "DIRTY HIGH." HV BASICALLY FOLLOWED WPC
GUIDANCE WITH 20 POPS EACH AFTN ALONG WITH NR NORMAL TEMPS, WITH
HIGHS ARND 80 AND LOWS IN THE 50S EXPECTED EACH PERIOD.
&&
.AVIATION /12Z SUNDAY THROUGH THURSDAY/...
LINE OF CONVECTION MOVING THROUGH AREA AT 11Z WILL BE EAST OF
TERMINALS BY 12Z BUT LINGERING MVFR CIGS ARE LIKELY THROUGH
MID/LATE MORNING. LATER THIS MORNING VFR CONDITIONS WITH JUST
SCT/BKN FAIR WX CU AND BKN CI EXPECTED. ISOLATED CONVECTION IS
POSSIBLE THIS AFTERNOON BUT NOT INCLUDED DUE TO VERY LIMITED AREAL
COVERAGE. THIS EVENING A DEEP UPPER LEVEL TROF AND ASSOCIATED SFC
LOW WILL BRING WIDESPREAD MODERATE SHOWERS TO THE TERMINALS.
ACROSS THE SOUTHERN TERMINALS BEGAN THIS ACTIVITY AROUND 00Z AND
AT 06Z AT KSYR/KRME.
S/SW WINDS EARLY THIS MORNING AROUND 5-8 KNOTS EXCEPT SE AT KRME.
AFTER MID MORNING SOUTHWEST WINDS AROUND 10 KNOTS BECOMING LIGHT
AND VARIABLE OVERNIGHT.
OUTLOOK...
MON-MON NGT...POTENTIAL RESTRICTIONS IN SHRA/TSRA.
TUE-THU...RESTRICTIONS POSSIBLE EACH AFTERNOON IN SHRA.
&&
.BGM WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NY...NONE.
&&
$$
SYNOPSIS...DJN
NEAR TERM...DJN
SHORT TERM...DJN
LONG TERM...PVN/RRM
AVIATION...RRM
AREA FORECAST DISCUSSION
NWS GRAND FORKS ND
943 AM CDT SUN JUL 27 2014
.UPDATE...
ISSUED AT 943 AM CDT SUN JUL 27 2014
NO UPDATES PLANNED AT THIS TIME. IT WILL REMAIN CLOUDY AND BREEZY
WITH A FEW SHOWERS AROUND TODAY. WILL HAVE TO MONITOR NORTHERN OR
NORTHWEST AREAS FOR THE POTENTIAL FOR SOME DECREASING AFTERNOON
CLOUDS.
&&
.SHORT TERM...(TODAY THROUGH MONDAY)
ISSUED AT 246 AM CDT SUN JUL 27 2014
HOW MUCH PRECIP HANGS AROUND AS THE UPPER LOW MOVES OFF TO THE
EAST WILL BE THE MAIN FORECAST QUESTION FOR THE PERIOD.
SCATTERED SHOWERS CONTINUE FROM THE RED RIVER VALLEY EASTWARD AS
THE UPPER LOW SLOWLY MOVES SOUTHEASTWARD INTO NORTHERN MINNESOTA.
THE UPPER LOW WILL CONTINUE OFF INTO WI DURING THE DAY...WITH THE
SFC LOW ALSO HEADING OFF AND HIGH PRESSURE BUILDING INTO THE
REGION. THE BEST LIFT WITH THE UPPER LOW WILL EXIT THE AREA FAIRLY
EARLY IN THE DAY. HOWEVER...CONVECTIVE TEMPS REMAIN IN THE UPPER
60S TO LOW 70S...SO SOME REDEVELOPMENT IS NOT OUT OF THE QUESTION
AND THE HRRR SEEMS TO SHOW THIS TREND. THUS...CONTINUED TO KEEP
LOW POPS GOING THROUGH 00Z. TEMPS WILL BE MOSTLY IN THE LOW 70S
WITH NORTH WINDS LESS BREEZY THAN YESTERDAY.
NORTHWESTERLY FLOW ALOFT SETS UP FOR TONIGHT AND CONTINUES INTO
MONDAY. SFC HIGH PRESSURE WILL REMAIN OVER THE NORTHERN PLAINS AND
BRING LIGHT NORTH WINDS. THE NAM WAS SHOWING SOME SIGNS OF A WEAK
SHORTWAVE IN THE NORTHWESTERLY FLOW APPROACHING THE LAKE OF THE
WOODS AREA AND BRINGING SOME ADDITIONAL PRECIP. HOWEVER...IT SEEMS
TO BE AN OUTLIER SO WILL KEEP IT DRY FOR NOW. LOWS TONIGHT SHOULD
DROP QUITE NICELY TO THE LOW 50S UNDER THE SFC HIGH...WITH
AFTERNOON TEMPS ON MONDAY GETTING INTO THE 70S.
.LONG TERM...(MONDAY NIGHT THROUGH SATURDAY)
ISSUED AT 246 AM CDT SUN JUL 27 2014
MONDAY NIGHT THROUGH TUESDAY NIGHT...NORTHWESTERLY FLOW ALOFT AND
SFC HIGH PRESSURE CONTINUE. WITH NOTHING TO FORCE THUNDERSTORM
DEVELOPMENT AND NOT EVEN ANY REAL RETURN FLOW...EXPECT US TO
REMAIN DRY THROUGH THE EARLY PART OF THE WORK WEEK. TEMPS WILL
CONTINUE TO BE SLIGHTLY BELOW SEASONAL AVERAGES ALTHOUGH THEY
SHOULD SLOWLY WARM.
WEDNESDAY-SATURDAY...MAINLY DRY CONDITIONS WITH SEASONABLE TEMPS AND
LIGHT WINDS WILL CONTINUE INTO NEXT WEEKEND...AS THE EASTERN US
TROUGH/WESTERN US RIDGE KEEPS THE NORTHERN PLAINS REGION IN A VERY
QUIET NORTHWEST FLOW PATTERN. ANY PRECIP CHANCES WITH WEAK WAVES
DROPPING OUT OF CANADA ARE TOO LOW TO MENTION RIGHT NOW. TEMPS WILL
SLOWLY WARM THROUGH LATE WEEK.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z MONDAY MORNING)
ISSUED AT 636 AM CDT SUN JUL 27 2014
MVFR TO A FEW IFR CIGS COVER THE AREA AS MOISTURE WRAPS AROUND THE
BACK SIDE OF THE LOW PRESSURE SYSTEM. THINK THESE LOWER CIGS
SHOULD CONTINUE THROUGH MUCH OF THE MORNING BEFORE RECOVERING TO
VFR BY AFTERNOON. SOME SCATTERED SHOWERS BUT JUST KEPT A MENTION
FOR KBJI AS THE COVERAGE WILL BE HIT AND MISS AND EAST OF THE TAF
SITES. THINK THAT CLOUDS WILL BEGIN TO SCATTER OUT BY THE EVENING.
NORTH WINDS WILL CONTINUE TO SEE GUSTS ABOVE 20 KTS FOR A WHILE
LONGER TODAY...BUT SHOULD DROP DOWN BELOW 12 KTS BY THIS EVENING.
&&
.FGF WATCHES/WARNINGS/ADVISORIES...
ND...NONE.
MN...NONE.
&&
$$
UPDATE...GODON
SHORT TERM...JR
LONG TERM...JR/MAKOWSKI
AVIATION...JR
AREA FORECAST DISCUSSION
NWS BISMARCK ND
927 AM CDT SUN JUL 27 2014
.UPDATE...
ISSUED AT 925 AM CDT SUN JUL 27 2014
ONLY CHANGE FOR MORNING UPDATE IS TO UP CLOUD COVER A BIT. CURRENT
TRENDS ARE KEEPING CLOUD COVER AROUND LONGER THAN PREVIOUSLY
THOUGHT...THOUGH STILL EXPECT IT TO DECREASE SOME BY AFTERNOON.
UPDATES HAVE BEEN SENT.
UPDATE ISSUED AT 625 AM CDT SUN JUL 27 2014
INITIALIZED THE GRIDS WITH THE LOW CLOUD SATELLITE CHANNEL AND THAT
BEEFED UP THE CLOUD COVER A BIT ACROSS MOST OF THE WEST AND
CENTRAL. SATELLITE LOOPS SHOWING STRATO CU A LITTLE MORE PERVASIVE
THIS MORNING. THE TREND WILL STILL BE DECREASING CLOUDS BY THIS
AFTERNOON AS THE UPPER LOW LEAVES THE AREA.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 308 AM CDT SUN JUL 27 2014
LATEST WATER VAPOR IMAGERY SHOWS AN UPPER CLOSED LOW OVER NORTHERN
MINNESOTA WITH A COMPENSATING NORTHERLY TO NORTHWESTERLY FLOW INTO
NORTH DAKOTA. FOG/STRATUS LOOP AND SURFACE OBSERVATIONS SHOW SEVERAL
POCKETS OF BKN/OVC LOW CLOUDS CONTINUING TO MOVE FROM NORTHERN
NORTH DAKOTA INTO CENTRAL NORTH DAKOTA. PER HRRR CEILING
FORECAST...EXPECT THESE CLOUDS TO LINGER THROUGH MID MORNING THEN
LIFT INTO A FAIRLY LARGE SCT/BKN STRATOCUMULUS FIELD THROUGH THE
AFTERNOON. ENOUGH INSTABILITY WILL EXIST OVER THE FAR SOUTHERN
JAMES RIVER VALLEY/EASTERN LAMOURE AND DICKEY COUNTIES PER
GFS/ECMWF FOR AN ISOLATED AFTERNOON SHOWER OR THUNDERSHOWER. THE
REST OF WESTERN AND CENTRAL NORTH DAKOTA WILL BE DRY. 850MB TEMPS
GENERALLY THE SAME OR 1C COOLER OVER SATURDAYS. WITH CLOUDS
LINGERING MORE ACROSS THE NORTH AND EAST...HIGH TEMPERATURES WILL
ONLY REACH THE LOWER 70S. EXPECT HIGHS IN THE MID/UPPER 70S WEST
THROUGH SOUTH CENTRAL. FOR SUNDAY NIGHT...A SURFACE HIGH PRESSURE
WILL SPREAD ACROSS NORTH CENTRAL NORTH DAKOTA WITH A CLEAR SKY AND
COOL TEMPERATURES. OVERNIGHT LOWS WILL BE AROUND 50F.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 308 AM CDT SUN JUL 27 2014
THE MAIN FEATURE IN THE EXTENDED PERIOD WILL BE A BLOCKING
WEATHER PATTERN FEATURING A LONG WAVE TROUGH OVER THE EASTERN US
AND A RIDGE OVER THE WEST. THIS WILL LEAVE THE NORTHERN PLAINS
GENERALLY CUTOFF FROM GULF MOISTURE AND POPS THROUGH THE PERIOD ARE
LOW. ALTHOUGH NORTHWEST FLOW CAN OFTEN BRING SURPRISE CONVECTION AS
WEAK IMPULSES ARE INEVITABLE EMBEDDED IN THE NORTHWEST FLOW FOR
NOW WILL LEAVE THIS PERIOD DRY. FOR TEMPERATURES EXPECT A GRADUAL
MODERATING TREND FROM BELOW NORMAL TEMPERATURES MONDAY TO NEAR OR
ABOVE NORMAL BY THE WEEKEND.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z MONDAY MORNING)
ISSUED AT 625 AM CDT SUN JUL 27 2014
SCT/BKN MVFR CIGS WILL DOMINATE ALL TERMINALS THROUGH MID MORNING
THEN GRADUALLY LIFT TO LOW VFR BETWEEN 16Z AND 18Z...EXCEPT AT KJMS
WHERE THE MVFR CIGS WILL BE MAINTAINED THROUGH 21Z SUNDAY. AS THE
MVFR CIGS LIFT TO VFR...EXPECT A WIDESPREAD SCT/BKN STRATOCUMULUS
FIELD FOR MUCH OF THE AFTERNOON. A CLEARING SKY WILL COMMENCE
NEAR/AROUND SUNSET. NORTHERLY WINDS WILL RANGE BETWEEN 10KT AND 15KT
THROUGH SUNSET THEN BECOMING LIGHT THEREAFTER.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...JJS
SHORT TERM...KS
LONG TERM...WAA
AVIATION...WAA
AREA FORECAST DISCUSSION
NWS GRAND FORKS ND
636 AM CDT SUN JUL 27 2014
.UPDATE...
ISSUED AT 636 AM CDT SUN JUL 27 2014
TWEAKED POPS A BIT FOR CURRENT RADAR TRENDS...BUT OVERALL KEPT
SCATTERED SHOWERS GOING MAINLY EAST OF THE RED RIVER AS THE UPPER
LOW CONTINUES TO SLOWLY PULL AWAY FROM THE REGION.
&&
.SHORT TERM...(TODAY THROUGH MONDAY)
ISSUED AT 246 AM CDT SUN JUL 27 2014
HOW MUCH PRECIP HANGS AROUND AS THE UPPER LOW MOVES OFF TO THE
EAST WILL BE THE MAIN FORECAST QUESTION FOR THE PERIOD.
SCATTERED SHOWERS CONTINUE FROM THE RED RIVER VALLEY EASTWARD AS
THE UPPER LOW SLOWLY MOVES SOUTHEASTWARD INTO NORTHERN MINNESOTA.
THE UPPER LOW WILL CONTINUE OFF INTO WI DURING THE DAY...WITH THE
SFC LOW ALSO HEADING OFF AND HIGH PRESSURE BUILDING INTO THE
REGION. THE BEST LIFT WITH THE UPPER LOW WILL EXIT THE AREA FAIRLY
EARLY IN THE DAY. HOWEVER...CONVECTIVE TEMPS REMAIN IN THE UPPER
60S TO LOW 70S...SO SOME REDEVELOPMENT IS NOT OUT OF THE QUESTION
AND THE HRRR SEEMS TO SHOW THIS TREND. THUS...CONTINUED TO KEEP
LOW POPS GOING THROUGH 00Z. TEMPS WILL BE MOSTLY IN THE LOW 70S
WITH NORTH WINDS LESS BREEZY THAN YESTERDAY.
NORTHWESTERLY FLOW ALOFT SETS UP FOR TONIGHT AND CONTINUES INTO
MONDAY. SFC HIGH PRESSURE WILL REMAIN OVER THE NORTHERN PLAINS AND
BRING LIGHT NORTH WINDS. THE NAM WAS SHOWING SOME SIGNS OF A WEAK
SHORTWAVE IN THE NORTHWESTERLY FLOW APPROACHING THE LAKE OF THE
WOODS AREA AND BRINGING SOME ADDITIONAL PRECIP. HOWEVER...IT SEEMS
TO BE AN OUTLIER SO WILL KEEP IT DRY FOR NOW. LOWS TONIGHT SHOULD
DROP QUITE NICELY TO THE LOW 50S UNDER THE SFC HIGH...WITH
AFTERNOON TEMPS ON MONDAY GETTING INTO THE 70S.
.LONG TERM...(MONDAY NIGHT THROUGH SATURDAY)
ISSUED AT 246 AM CDT SUN JUL 27 2014
MONDAY NIGHT THROUGH TUESDAY NIGHT...NORTHWESTERLY FLOW ALOFT AND
SFC HIGH PRESSURE CONTINUE. WITH NOTHING TO FORCE THUNDERSTORM
DEVELOPMENT AND NOT EVEN ANY REAL RETURN FLOW...EXPECT US TO
REMAIN DRY THROUGH THE EARLY PART OF THE WORK WEEK. TEMPS WILL
CONTINUE TO BE SLIGHTLY BELOW SEASONAL AVERAGES ALTHOUGH THEY
SHOULD SLOWLY WARM.
WEDNESDAY-SATURDAY...MAINLY DRY CONDITIONS WITH SEASONABLE TEMPS AND
LIGHT WINDS WILL CONTINUE INTO NEXT WEEKEND...AS THE EASTERN US
TROUGH/WESTERN US RIDGE KEEPS THE NORTHERN PLAINS REGION IN A VERY
QUIET NORTHWEST FLOW PATTERN. ANY PRECIP CHANCES WITH WEAK WAVES
DROPPING OUT OF CANADA ARE TOO LOW TO MENTION RIGHT NOW. TEMPS WILL
SLOWLY WARM THROUGH LATE WEEK.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z MONDAY MORNING)
ISSUED AT 636 AM CDT SUN JUL 27 2014
MVFR TO A FEW IFR CIGS COVER THE AREA AS MOISTURE WRAPS AROUND THE
BACK SIDE OF THE LOW PRESSURE SYSTEM. THINK THESE LOWER CIGS
SHOULD CONTINUE THROUGH MUCH OF THE MORNING BEFORE RECOVERING TO
VFR BY AFTERNOON. SOME SCATTERED SHOWERS BUT JUST KEPT A MENTION
FOR KBJI AS THE COVERAGE WILL BE HIT AND MISS AND EAST OF THE TAF
SITES. THINK THAT CLOUDS WILL BEGIN TO SCATTER OUT BY THE EVENING.
NORTH WINDS WILL CONTINUE TO SEE GUSTS ABOVE 20 KTS FOR A WHILE
LONGER TODAY...BUT SHOULD DROP DOWN BELOW 12 KTS BY THIS EVENING.
&&
.FGF WATCHES/WARNINGS/ADVISORIES...
ND...NONE.
MN...NONE.
&&
$$
UPDATE...JR
SHORT TERM...JR
LONG TERM...JR/MAKOWSKI
AVIATION...JR
AREA FORECAST DISCUSSION
NWS BISMARCK ND
628 AM CDT SUN JUL 27 2014
.UPDATE...
ISSUED AT 625 AM CDT SUN JUL 27 2014
INITIALIZED THE GRIDS WITH THE LOW CLOUD SATELLITE CHANNEL AND THAT
BEEFED UP THE CLOUD COVER A BIT ACROSS MOST OF THE WEST AND
CENTRAL. SATELLITE LOOPS SHOWING STRATO CU A LITTLE MORE PERVASIVE
THIS MORNING. THE TREND WILL STILL BE DECREASING CLOUDS BY THIS
AFTERNOON AS THE UPPER LOW LEAVES THE AREA.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 308 AM CDT SUN JUL 27 2014
LATEST WATER VAPOR IMAGERY SHOWS AN UPPER CLOSED LOW OVER NORTHERN
MINNESOTA WITH A COMPENSATING NORTHERLY TO NORTHWESTERLY FLOW INTO
NORTH DAKOTA. FOG/STRATUS LOOP AND SURFACE OBSERVATIONS SHOW SEVERAL
POCKETS OF BKN/OVC LOW CLOUDS CONTINUING TO MOVE FROM NORTHERN
NORTH DAKOTA INTO CENTRAL NORTH DAKOTA. PER HRRR CEILING
FORECAST...EXPECT THESE CLOUDS TO LINGER THROUGH MID MORNING THEN
LIFT INTO A FAIRLY LARGE SCT/BKN STRATOCUMULUS FIELD THROUGH THE
AFTERNOON. ENOUGH INSTABILITY WILL EXIST OVER THE FAR SOUTHERN
JAMES RIVER VALLEY/EASTERN LAMOURE AND DICKEY COUNTIES PER
GFS/ECMWF FOR AN ISOLATED AFTERNOON SHOWER OR THUNDERSHOWER. THE
REST OF WESTERN AND CENTRAL NORTH DAKOTA WILL BE DRY. 850MB TEMPS
GENERALLY THE SAME OR 1C COOLER OVER SATURDAYS. WITH CLOUDS
LINGERING MORE ACROSS THE NORTH AND EAST...HIGH TEMPERATURES WILL
ONLY REACH THE LOWER 70S. EXPECT HIGHS IN THE MID/UPPER 70S WEST
THROUGH SOUTH CENTRAL. FOR SUNDAY NIGHT...A SURFACE HIGH PRESSURE
WILL SPREAD ACROSS NORTH CENTRAL NORTH DAKOTA WITH A CLEAR SKY AND
COOL TEMPERATURES. OVERNIGHT LOWS WILL BE AROUND 50F.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 308 AM CDT SUN JUL 27 2014
THE MAIN FEATURE IN THE EXTENDED PERIOD WILL BE A BLOCKING
WEATHER PATTERN FEATURING A LONG WAVE TROUGH OVER THE EASTERN US
AND A RIDGE OVER THE WEST. THIS WILL LEAVE THE NORTHERN PLAINS
GENERALLY CUTOFF FROM GULF MOISTURE AND POPS THROUGH THE PERIOD ARE
LOW. ALTHOUGH NORTHWEST FLOW CAN OFTEN BRING SURPRISE CONVECTION AS
WEAK IMPULSES ARE INEVITABLE EMBEDDED IN THE NORTHWEST FLOW FOR
NOW WILL LEAVE THIS PERIOD DRY. FOR TEMPERATURES EXPECT A GRADUAL
MODERATING TREND FROM BELOW NORMAL TEMPERATURES MONDAY TO NEAR OR
ABOVE NORMAL BY THE WEEKEND.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z MONDAY MORNING)
ISSUED AT 625 AM CDT SUN JUL 27 2014
SCT/BKN MVFR CIGS WILL DOMINATE ALL TERMINALS THROUGH MID MORNING
THEN GRADUALLY LIFT TO LOW VFR BETWEEN 16Z AND 18Z...EXCEPT AT KJMS
WHERE THE MVFR CIGS WILL BE MAINTAINED THROUGH 21Z SUNDAY. AS THE
MVFR CIGS LIFT TO VFR...EXPECT A WIDESPREAD SCT/BKN STRATOCUMULUS
FIELD FOR MUCH OF THE AFTERNOON. A CLEARING SKY WILL COMMENCE
NEAR/AROUND SUNSET. NORTHERLY WINDS WILL RANGE BETWEEN 10KT AND 15KT
THROUGH SUNSET THEN BECOMING LIGHT THEREAFTER.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...WAA
SHORT TERM...KS
LONG TERM...WAA
AVIATION...WAA
AREA FORECAST DISCUSSION
NWS MEMPHIS TN
1013 AM CDT SUN JUL 27 2014
.UPDATE...MORNING UPDATE.
AS OF 10AM...TEMPERATURES ARE RUNNING ABOUT THE SAME AS YESTERDAY
AT THIS TIME WITH READINGS IN THE LOW TO MID 80S. A MID LEVEL BROKEN
STRATUS DECK RESIDES OVER THE MIDDLE THIRD OF THE FA...BUT SHOULD
BEGIN TO MIX OUT VERY SOON KEEPING TEMPERATURES ON TRACK TO TOP
OUT IN THE LOW TO MID 90S THIS AFTERNOON. CURRENT DEWPOINTS ARE IN
THE MID 70S...PUTTING MOST AREAS AT HEAT INDEX VALUES OF MID TO
UPPER 90S ALREADY. OPTED FOR A HEAT ADVISORY IN THE SOUTHERN TWO
THIRDS OF THE AREA...WHERE HEAT INDEX VALUES WILL MEET OR EXCEED
THE 105 DEGREE THRESHOLD. A COLD FRONT CURRENTLY EXTENDS FROM
SOUTHERN MI...DOWN THROUGH CENTRAL IL...AND INTO CENTRAL MO.
LATEST MODEL GUIDANCE INDICATES VERY LARGE INSTABILITY OVER MUCH
OF THE MID-SOUTH FOR THIS AFTERNOON WITH SBCAPE VALUES IN EXCESS
OF 4000 J/KG AND LI`S NEAR -10C. LATEST HRRR DEPICTS STORM
INITIATION JUST AHEAD OF THE FRONT IN THE 22Z-00Z TIME RANGE ALONG
A LINE FROM JONESBORO AR TO PARIS TN AND THEN MOVING SOUTHWARD
INTO THE MEMPHIS METRO AS A BROKEN LINE THROUGH SUNSET. ANY STORMS
THAT DO INITIATE WILL LIKELY GO SEVERE DUE TO THE AMOUNT OF PURE
INSTABILITY. THE PRIMARY HAZARDS STILL APPEAR TO BE DAMAGING WINDS
AND LARGE HAIL. UPDATED THE HWO TO INCLUDE A SLIGHT RISK OF SEVERE
THUNDERSTORMS OVER THE MISSOURI BOOTHEEL...ALL OF WEST TENNESSEE...AND
MOST OF NORTHEAST ARKANSAS.
ALL OTHER FORECASTED PARAMETERS ARE ON TRACK. NEW GRIDS AND ZONES
WILL BE AVAILABLE SOON.
AC3
&&
.PREV DISCUSSION... /ISSUED 404 AM CDT SUN JUL 27 2014/
DISCUSSION...
ITS A WARM MUGGY SUMMER NIGHT ACROSS THE MIDSOUTH. TEMPERATURES
REMAIN IN THE LOW 80S AT THE WARMEST LOCATIONS ACROSS THE REGION
INCLUDING THE MEMPHIS METRO AREA WITH THE REMAINDER OF THE REGION
IN THE MIDDLE TO UPPER 70S. MORNING LOWS WILL LIKELY BE IN THE
MIDDLE TO UPPER 70S. TODAY MIGHT BE THE WARMEST DAY WE HAVE SEEN
SO FAR THIS YEAR...AND LIKELY THE WARMEST DAY FOR THE NEXT WEEK OR
SO. AFTERNOON HIGHS WILL BE IN THE MIDDLE 90S. WITH HEAT INDICES
BETWEEN 100 AND 104 DEGREES...JUST BELOW HEAT ADVISORY CRITERIA.
GUIDANCE HAS BEEN RUNNING 2-4 DEGREES TOO WARM RECENTLY SO SHAVED
A COUPLE OF DEGREES OFF MOS GUIDANCE NUMBERS WHICH ARE IN THE
97-98 DEGREE RANGE FOR MUCH OF THE MIDSOUTH. AFTERNOON CLOUD COVER
AND SCATTERED SHOWERS AND THUNDERSTORMS WILL ALSO HELP TO LIMIT
AFTERNOON HEATING. THE STORM PREDICTION CENTER HAS PLACED PORTIONS
OF WEST TENNESSEE...GENERALLY NORTH OF INTERSTATE 40 UNDER A
SLIGHT RISK FOR SEVERE THUNDERSTORMS THIS AFTERNOON INTO TONIGHT.
A COLD FRONT WILL MOVE INTO THE AREA THIS EVENING HELPING TO FOCUS
LIFT ACROSS THE REGION. DEW POINTS ARE IN THE MIDDLE 70S. AS
TEMPERATURES WARM...AHEAD OF THE COLD FRONT...AFTERNOON CAPE
VALUES WILL CLIMB IN EXCESS OF 3500 J/KG WITH LI`S BELOW -9C. STORMS
WILL LIKELY TURN SEVERE VERY QUICKLY AS THEY DEVELOP. THE GREATEST
THREAT FOR SEVERE WEATHER WILL BE TO OUR EAST WHERE A MID LEVEL
JET WILL ENHANCE STORMS...BUT AREAS AS FAR WEST AS THE MISSOURI
BOOTHEEL AND JACKSON TENNESSEE COULD SEE SEVERE STORMS. DAMAGING
WIND IS THE PRIMARY THREAT...BUT LARGE HAIL AND LOCALIZED FLOODING
ARE ALSO POSSIBLE. THREE HOUR FLASH FLOOD GUIDANCE IS GENERALLY
2.5 TO 3.5 INCHES ACROSS THE AREA. HPC QPF GUIDANCE IS ONLY ABOUT
ONE QUARTER OF AN INCH OR LESS...SO WIDESPREAD FLOODING PROBLEMS
ARE NOT EXPECTED. HOWEVER WITH GUIDANCE...PW VALUES IN EXCESS OF
TWO INCHES...LOCALLY HEAVY RAINFALL IS LIKELY. STORMS WILL LIKELY
CONTINUE OVERNIGHT...BUT COVERAGE AND INTENSITY SHOULD SLOWLY
DIMINISH.
MONDAY...COOLER CONDITIONS WILL RETURN TO THE MIDSOUTH. MUCH LIKE
WE HAVE SEEN FOR MOST OF THE SUMMER SO FAR. HIGHS MONDAY WILL BE
5-8 DEGREES BELOW NORMAL...IN THE LOW TO MIDDLE 80S ACROSS MOST OF
THE AREA. MORNING LOWS MIDWEEK MAY FALL INTO THE MID TO UPPER 50S
AT THE COOLEST LOCATIONS WITH MOST AREAS IN THE LOWER 60S.
TEMPERATURES WILL TREND A DEGREE OR TWO WARMER EACH DAY DURING THE
WORK WEEK...BUT REMAIN BELOW NORMAL. BY FRIDAY HIGHS MAY APPROACH
90 DEGREES AT THE WARMEST LOCATIONS. ANOTHER COLD FRONT LOOKS
POSSIBLE FRIDAY INTO NEXT WEEKEND. GUIDANCE POPS REMAIN PRETTY LOW
DUE TO LACK OF MOISTURE. WILL KEEP CONDITIONS DRY FOR NOW...BUT
WOULDN`T BE SURPRISED TO SEE A FEW SHOWERS AROUND IN UPCOMING
MODEL RUNS.
30
&&
.AVIATION...
12Z TAF CYCLE
VFR CONDITIONS SHOULD PERSIST FOR MUCH OF THE FORECAST PERIOD.
SOME SCATTERED THUNDERSTORMS MAY DEVELOP OVER NORTHERN SECTIONS OF
THE FORECAST AREA THIS AFTERNOON AND OVER THE ENTIRE FORECAST AREA
TONIGHT. KMKL APPEARS TO HAVE THE BEST CHANCE AMONG THE TAF SITES
TO SEE THUNDERSTORM SO HAVE VCTS THERE OTHERWISE COVERAGE SHOULD
REMAIN LIMITED ENOUGH TO LEAVE OUT OF TAFS FOR NOW. WINDS WILL BE
SOUTHWEST TODAY INCREASING TO 10 TO 15 KNOTS WITH A FEW HIGHER
GUSTS THIS AFTERNOON. WINDS WILL SHIFT TO THE NORTHWEST TONIGHT
AND DIMINISH TO 5 TO 10 KNOTS.
ARS
&&
.MEG WATCHES/WARNINGS/ADVISORIES...
AR...NONE.
MO...NONE.
MS...NONE.
TN...NONE.
&&
$$
AREA FORECAST DISCUSSION...UPDATED
NWS MILWAUKEE/SULLIVAN WI
1032 AM CDT SUN JUL 27 2014
.UPDATE...
SCATTERED SHOWERS AND STORMS ARE QUICKLY DEVELOPING THIS MORNING
UPSTREAM AS EXPECTED. WILL SEE THIS ACTIVITY PUSH SOUTH INTO THE
FORECAST AREA LATE MORNING INTO THE AFTERNOON AS THE TROUGH AXIS
ROTATES THROUGH. STILL EXPECT DAYTIME HIGH TEMPERATURES TO BE LATE
THIS MORNING INTO EARLY AFTERNOON...WITH DECREASING TEMPS AFTER
THAT FROM NORTHWEST TO SOUTHEAST AS THE CLOUDS/SHOWERS AND COLDER
AIR ALOFT MOVE IN.
&&
.AVIATION/18Z TAFS/...
SCATTERED SHOWERS AND STORMS ARE QUICKLY DEVELOPING THIS MORNING
UPSTREAM AS EXPECTED. WILL SEE THIS ACTIVITY PUSH SOUTH INTO THE
FORECAST AREA LATE MORNING INTO THE AFTERNOON AS THE TROUGH AXIS
ROTATES THROUGH. SHOWERS WILL WIND DOWN EARLY THIS EVENING.
MAINLY VFR CONDITIONS ARE EXPECTED TODAY EXCEPT FOR MVFR VSBYS
POSSIBLE WITHIN MODERATE RAINFALL. WILL ALSO MONITOR POSSIBLE
MVFR CIGS AS MAIN COLD POOL ALOFT PUSHES THROUGH TONIGHT...THOUGH
MODEL SOUNDINGS AND MOS SUGGEST VFR CIGS.
IT LOOKS PRETTY QUIET THEN MONDAY AS HIGH PRESSURE MOVES INTO THE
AREA.
&&
.PREV DISCUSSION... /ISSUED 313 AM CDT SUN JUL 27 2014/
TODAY AND TONIGHT...FORECAST CONFIDENCE IS HIGH.
A SURFACE COLD FRONT WILL PUSH ACROSS THE FORECAST AREA THIS
MORNING...REACHING MADISON BY 14Z AND MILWAUKEE BETWEEN 16-17Z. WE
COULD SEE A LINE OF SHOWERS AND STORMS DEVELOP ALONG THE FRONT
OVER THE CWA BEFORE IT EXITS TO THE EAST. HEIGHTS ARE FALLING AS
AN IMPRESSIVELY STRONG UPPER TROF DROPS SOUTH INTO THE WESTERN
GREAT LAKES. UP UNTIL NOW...THE COLUMN HAS BEEN FAIRLY DRY IN THE
MID LEVELS OVER SOUTHERN WI WITH DECENT CAPPING IN THE LOW
LEVELS...LIMITING CONVECTIVE DEVELOPMENT. BUT THIS WILL BE
MOISTENING UP QUICKLY JUST AS TEMPS ALOFT ARE COOLING.
THE HRRR SHOWS CONVECTION DEVELOPING ALONG THE FRONT JUST AS IT/S
GETTING TO MADISON. THIS ISN/T A SURE THING...BUT IT LOOKS LIKE A
REASONABLE AND POSSIBLE SCENARIO. BEHIND THE FRONT...THE COLD CORE
UPPER SYSTEM DROPS IN AND PRECIP SHOULD EXPAND UNDER THIS LOW BY
EARLY TO MID AFTERNOON...ESPECIALLY OVER THE NORTHEAST CWA. THIS
WILL BE MAINLY SHOWERS...BUT WE COULD CRACK SOME THUNDER...SO WILL
KEEP THAT MENTION.
DRIER WEATHER WORKS IN QUICKLY TONIGHT IN THE WAKE OF A SECONDARY
COLD FRONT THAT CLEARS SOUTHERN WISCONSIN BY ABOUT 03Z SUN. THIS
WILL BRING CLEARING SKIES WITH TEMPS FALLING INTO THE 50S.
SHORT TERM...MONDAY THROUGH TUESDAY NIGHT...FORECAST CONFIDENCE
IS MEDIUM.
SHORT TERM MODELS SHOWING 500 MB TROUGH LINGERING OVER
SOUTHEASTERN CANADA INTO THE EASTERN USA DURING THIS PERIOD. THE
UPPER MIDWEST SHOULD REMAIN IN NORTHWESTERLY FLOW AS A RESULT.
WEAK 500 MB VORTICITY MAXIMA PASS THROUGH THE AREA...MAINLY
TUESDAY INTO TUESDAY NIGHT. MODELS ARE SHOWING LIGHT QPF ACROSS
PORTIONS OF THE AREA DURING THIS TIME.
AREA FORECAST SOUNDINGS SHOW ENOUGH SHALLOW MEAN LAYER CAPE FOR
SHOWERS AND A FEW THUNDERSTORMS TUESDAY INTO TUESDAY NIGHT.
CONTINUED POPS FOR TUESDAY AND TUESDAY NIGHT...WITH MONDAY AND
MONDAY NIGHT DRY.
TEMPERATURES WILL BE BELOW SEASONAL NORMALS MONDAY...WITH 925 MB
TEMPERATURES SUPPORTING LOWER 70S EAST TO MID 70S WEST. COOL NIGHT
MONDAY NIGHT WITH LOWS IN THE LOWER TO MID 50S ARE EXPECTED...WITH
MID TO UPPER 70S ON TUESDAY.
LONG TERM...WEDNESDAY THROUGH SATURDAY...FORECAST CONFIDENCE IS
MEDIUM.
ECMWF/GFS CONTINUE TO SHOW 500 MB TROUGH LINGERING TO THE EAST OF
THE REGION THROUGH THURSDAY NIGHT...WITH ANOTHER TROUGH ROTATING
INTO THE AREA FRIDAY INTO SATURDAY. VARIOUS VORTICITY MAXIMA
SHOULD CONTINUE TO ROTATE THROUGH THE REGION AT TIMES.
GFS FORECAST SOUNDINGS SHOW SOME WEAK INSTABILITY EACH AFTERNOON
AND EVENING DURING THIS PERIOD...WHICH MAY ALLOW FOR SHOWERS AND A
FEW STORMS. KEPT POPS GOING FOR MOST OF THIS PERIOD...GIVEN SOME
UNCERTAINTY WITH THE EXACT TIMING OF PRECIPITATION. TEMPERATURES
SHOULD BE PLEASANT DURING THIS TIME...WITH ONSHORE WINDS AT TIMES
NEAR LAKE MICHIGAN KEEPING THINGS COOLER THERE.
AVIATION/12Z TAFS/...
LOOK FOR RAPIDLY CHANGING CONDITIONS THROUGH THE TAF PERIOD. WE
START OUT WITH SOME AREAS OF FOG AND POSSIBLE IFR/MVFR
CONDITIONS...BUT THIS WILL ONLY BE A THREAT THROUGH ABOUT 15Z THIS
MORNING. THEREAFTER WINDS INCREASE AHEAD OF AN APPROACHING COLD
FRONT AND THIS SHOULD MIX OUT ANY FOG/LOW CLOUDS.
THE COLD FRONT WILL REACH KMSN BY 14Z AND KMKE/KENW/KUES BTWN
16-17Z. THERE IS A THREAT OF SHOWERS AND STORMS ALONG AND AHEAD OF
THE FRONT...BUT CONDITIONS SHOULD REMAIN AT VFR LEVELS. BEHIND THE
FRONT...COOLER UPPER LEVELS WITH THE ARRIVAL OF A STRONG MID LEVEL
SHORT WAVE WILL RESULT IN EXPANDING PRECIPITATION BY EARLY
AFTERNOON. THIS WILL BE MOSTLY SHOWERS...BUT A THUNDERSTORM IS
POSSIBLE. STILL MAINLY VFR CONDITIONS EXPECTED.
A SECONDARY COLD FRONT WILL PUSH THROUGH THE AREA VERY LATE THIS
AFTERNOON OR EARLY THIS EVENING. THERE COULD BE A PERIOD OF MVFR
CIGS WITH THAT...BUT SKIES WILL CLEAR FROM NORTH TO SOUTH BY 06Z
MONDAY WITH DRIER AND COOLER WEATHER EXPECTED. LOOK FOR MAINLY VFR
CONDITIONS AFTER 06Z MON.
MARINE...
INCREASING NORTHERLY WINDS TO 15 TO 25 KNOTS BY THIS EVENING...IN
THE WAKE OF A PASSING COLD FRONT...WILL BRING SMALL CRAFT ADVISORY
CONDITIONS FROM ABOUT 4 PM THIS AFTERNOON INTO THE EARLY EVENING
ON SUNDAY. WAVES WILL BUILD TO 4 TO 7 FEET TONIGHT...DIMINISHING
SLOWLY ON SUNDAY.
BEACHES...
INCREASING NORTH WINDS WILL BRING BUILDING WAVES TO THE BEACHES
FROM SHEBOYGAN SOUTH THROUGH KENOSHA COUNTY. WAVES WILL REACH 3 TO
4 FEET ALONG THE SHORELINE BY EARLY THIS EVENING...BUILDING TO 4
TO 7 FEET TONIGHT...THEN DIMINISHING SLOWLY THROUGH THE AFTERNOON
INTO THE EARLY EVENING ON SUNDAY. A BEACH HAZARDS STATEMENT IS IN
EFFECT FROM THIS EVENING THROUGH MONDAY EVENING.
&&
.MKX WATCHES/WARNINGS/ADVISORIES...
WI...BEACH HAZARDS STATEMENT FROM 7 PM CDT THIS EVENING THROUGH
MONDAY EVENING FOR WIZ052-060-066-071-072.
LM...SMALL CRAFT ADVISORY FROM 4 PM THIS AFTERNOON TO 7 PM CDT MONDAY
FOR LMZ645-646.
SMALL CRAFT ADVISORY FROM 7 PM THIS EVENING TO 4 PM CDT MONDAY
FOR LMZ643-644.
&&
$$
UPDATE...DDV
TODAY/TONIGHT AND AVIATION/MARINE/BEACHES...DAVIS
MONDAY THROUGH SATURDAY...WOOD
AREA FORECAST DISCUSSION
NWS SAN JOAQUIN VALLEY - HANFORD CA
355 PM PDT SUN JUL 27 2014
.UPDATE...
UPDATED AIR QUALITY SECTION.
&&
.SYNOPSIS...
SOUTHERLY FLOW CONTINUES TO BRING MONSOONAL MOISTURE INTO THE REGION
AND WILL INCREASE CHANCES OF SHOWERS AND THUNDERSTORMS FOR THE
SIERRA CREST AND THE KERN COUNTY MOUNTAINS AND DESERT AREAS INTO
THE FIRST HALF OF THE WEEK. BEGINNING MONDAY SHOWERS AND
THUNDERSTORMS MAY SPREAD INTO SIERRA FOOTHILLS AND EASTERN AND
SOUTHERN PARTS OF THE SAN JOAQUIN VALLEY. OTHERWISE...TEMPERATURES
WILL REMAIN ON THE HOT SIDE THROUGH THE REMAINDER OF THE WEEK.
&&
.DISCUSSION...
SATELLITE LOOPS SHOW BANDS OF CLOUDS STREAMING NORTHWARD OVER
CALIFORNIA THIS AFTERNOON...INCLUDING ONE BAND THAT IS STREAMING
OVER KERN COUNTY INTO THE SOUTHERN SIERRA NEVADA. ALSO VISIBLE...IN
BREAKS BETWEEN CLOUDS...IS THE SMOKE PLUME FROM THE EL PORTAL FIRE
IN YOSEMITE NATIONAL PARK.
LIGHTNING DATA SHOW BOTH IN-CLOUD/CLOUD-CLOUD AND CLOUD-GROUND
LIGHTNING FROM THUNDERSTORMS OVER THE SOUTHERN SIERRA NEVADA...MAINLY
OVER TULARE AND FRESNO COUNTIES AT THIS TIME. THE LIGHTNING IS
SPREADING NORTHWARD AND THUNDERSTORMS COULD REACH YOSEMITE NATIONAL
PARK BY MID TO LATE AFTERNOON. THIS IS SLOWER TIMING THAN THE 19Z
HIGH-RESOLUTION RAPID-REFRESH /HRRR/ MODEL HAD FORECAST...WHICH HAD
THUNDER MOVING INTO THE PARK BY 20Z /1300 PDT/. THE HRRR DID MOVE
THE CONVECTION EAST OF THE SOUTHERN SIERRA NEVADA BY 06Z MONDAY
/2300 PDT TONIGHT/...BUT DID HAVE A STORM MOVING INTO THE FRAZIER
PARK/PINE MOUNTAIN CLUB AREA AT THAT TIME. BUILD-UPS OVER LOS
ANGELES COUNTY ARE MOVING TOWARD SOUTHERN KERN COUNTY THIS AFTERNOON
BUT NO LIGHTNING HAS BEEN DETECTED AT THIS TIME.
AT 19Z /NOON PDT/...BAKERSFIELD WAS RUNNING 2 DEGREES WARMER THAN AT
19Z SATURDAY...BUT FRESNO WAS RUNNING 2 DEGREES COOLER. CENTRAL AND
SOUTHERN SAN JOAQUIN VALLEY HIGH TEMPERATURES ARE ON TRACK TO REACH
103-106 DEGREES. TEMPERATURES MONDAY LIKELY WILL BE A FEW DEGREES
COOLER DUE TO INCREASED CLOUD COVER AS THE MONSOONAL MOISTURE
CONTINUES TO PUSH NORTHWARD INTO CENTRAL CALIFORNIA. THE 18Z NAM-12
FORECASTS NEAR SATURATION OF THE 700-500-MB LAYER OVER THE SOUTHERN
SIERRA NEVADA...TEHACHAPI MOUNTAINS AND KERN DESERT AREAS BY 15Z
/0800 PDT/ MONDAY WITH DRIER AIR MOVING INTO THE REGION FROM THE
SOUTH TUESDAY. WITH PARTIAL CLEARING TUESDAY...TEMPERATURES SHOULD
BE A COUPLE OF DEGREES WARMER THAN MONDAY.
AFTER MONDAY...THUNDERSTORMS ARE FORECAST TO BE CONFINED TO THE
HIGHER ELEVATIONS OF THE SOUTHERN SIERRA NEVADA THROUGH THE END OF
THE WEEK. THE ECMWF FORECASTS LITTLE CHANGE IN 850-MB TEMPERATURES
OVER THE CENTRAL SAN JOAQUIN VALLEY THROUGH MID-WEEK...THEN A SLIGHT
COOLING TREND AS AN UPPER-LEVEL TROUGH APPROACHES THE PACIFIC
NORTHWEST AND WEAKENS THE RIDGE. THE LATEST GFS...IN CONTRAST TO
BOTH THE ECMWF AND PREVIOUS GFS RUNS...PICKS UP ON THE COOLING FOR
MONDAY...THEN WARMS 850-MB TEMPERATURES TUESDAY THROUGH FRIDAY
BEFORE A BRIEF COOL-DOWN SATURDAY.
DESPITE THE MODEL DIFFERENCES...THE FORECAST OF 850-MB TEMPERATURES
MOSTLY BETWEEN 25-26 C OVER THE CENTRAL SAN JOAQUIN VALLEY FOR MUCH
OF THE COMING WEEK SUGGESTS THAT THE CENTRAL AND SOUTHERN SAN
JOAQUIN VALLEY LIKELY WILL SEE TEMPERATURES RUNNING A FEW DEGREES
ABOVE NORMAL THROUGH THE START OF AUGUST.
&&
.AVIATION...
ISOLATED THUNDERSTORMS CAN BE EXPECTED ALONG THE SIERRA CREST
UNTIL 04Z MONDAY WITH A RECURRENCE AFTER 19Z MONDAY. OTHERWISE...
VFR CONDITIONS WILL PREVAIL THROUGHOUT THE CENTRAL CALIFORNIA
INTERIOR DURING THE NEXT 24 HOURS.
&&
.AIR QUALITY ISSUES...
ON MONDAY JULY 28 2014... UNHEALTHY FOR SENSITIVE GROUPS IN FRESNO
AND MADERA COUNTIES.
FURTHER INFORMATION IS AVAILABLE AT VALLEYAIR.ORG
&&
.CERTAINTY...
THE LEVEL OF CERTAINTY FOR DAYS 1 AND 2 IS HIGH.
THE LEVEL OF CERTAINTY FOR DAYS 3 THROUGH 7 IS MEDIUM.
CERTAINTY LEVELS INCLUDE LOW...MEDIUM...AND HIGH. PLEASE VISIT
WWW.WEATHER.GOV/HNX/CERTAINTY.PHP /ALL LOWER CASE/ FOR ADDITIONAL
INFORMATION AND/OR TO PROVIDE FEEDBACK.
&&
.CLIMATE...
RECORDS
SITE DATE HI_MAX:YEAR LO_MAX:YEAR HI_MIN:YEAR LO_MIN:YEAR
KFAT 07-27 114:1933 83:1941 79:1933 52:1897
KFAT 07-28 110:1980 89:1941 82:1980 55:1892
KFAT 07-29 113:1898 87:1896 78:2003 57:1950
KBFL 07-27 117:1933 85:1965 83:1980 52:1914
KBFL 07-28 118:1908 85:1941 84:1931 50:1914
KBFL 07-29 114:1908 87:1965 86:2003 52:1914
&&
.HNX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
PUBLIC...SANGER
AVN/FW...DURFEE
SYNOPSIS...ANDERSEN
WEATHER.GOV/HANFORD
AREA FORECAST DISCUSSION
NWS SAN JOAQUIN VALLEY - HANFORD CA
210 PM PDT SUN JUL 27 2014
.SYNOPSIS...
SOUTHERLY FLOW CONTINUES TO BRING MONSOONAL MOISTURE INTO THE REGION
AND WILL INCREASE CHANCES OF SHOWERS AND THUNDERSTORMS FOR THE
SIERRA CREST AND THE KERN COUNTY MOUNTAINS AND DESERT AREAS INTO
THE FIRST HALF OF THE WEEK. BEGINNING MONDAY SHOWERS AND
THUNDERSTORMS MAY SPREAD INTO SIERRA FOOTHILLS AND EASTERN AND
SOUTHERN PARTS OF THE SAN JOAQUIN VALLEY. OTHERWISE...TEMPERATURES
WILL REMAIN ON THE HOT SIDE THROUGH THE REMAINDER OF THE WEEK.
&&
.DISCUSSION...
SATELLITE LOOPS SHOW BANDS OF CLOUDS STREAMING NORTHWARD OVER
CALIFORNIA THIS AFTERNOON...INCLUDING ONE BAND THAT IS STREAMING
OVER KERN COUNTY INTO THE SOUTHERN SIERRA NEVADA. ALSO VISIBLE...IN
BREAKS BETWEEN CLOUDS...IS THE SMOKE PLUME FROM THE EL PORTAL FIRE
IN YOSEMITE NATIONAL PARK.
LIGHTNING DATA SHOW BOTH IN-CLOUD/CLOUD-CLOUD AND CLOUD-GROUND
LIGHTNING FROM THUNDERSTORMS OVER THE SOUTHERN SIERRA NEVADA...MAINLY
OVER TULARE AND FRESNO COUNTIES AT THIS TIME. THE LIGHTNING IS
SPREADING NORTHWARD AND THUNDERSTORMS COULD REACH YOSEMITE NATIONAL
PARK BY MID TO LATE AFTERNOON. THIS IS SLOWER TIMING THAN THE 19Z
HIGH-RESOLUTION RAPID-REFRESH /HRRR/ MODEL HAD FORECAST...WHICH HAD
THUNDER MOVING INTO THE PARK BY 20Z /1300 PDT/. THE HRRR DID MOVE
THE CONVECTION EAST OF THE SOUTHERN SIERRA NEVADA BY 06Z MONDAY
/2300 PDT TONIGHT/...BUT DID HAVE A STORM MOVING INTO THE FRAZIER
PARK/PINE MOUNTAIN CLUB AREA AT THAT TIME. BUILD-UPS OVER LOS
ANGELES COUNTY ARE MOVING TOWARD SOUTHERN KERN COUNTY THIS AFTERNOON
BUT NO LIGHTNING HAS BEEN DETECTED AT THIS TIME.
AT 19Z /NOON PDT/...BAKERSFIELD WAS RUNNING 2 DEGREES WARMER THAN AT
19Z SATURDAY...BUT FRESNO WAS RUNNING 2 DEGREES COOLER. CENTRAL AND
SOUTHERN SAN JOAQUIN VALLEY HIGH TEMPERATURES ARE ON TRACK TO REACH
103-106 DEGREES. TEMPERATURES MONDAY LIKELY WILL BE A FEW DEGREES
COOLER DUE TO INCREASED CLOUD COVER AS THE MONSOONAL MOISTURE
CONTINUES TO PUSH NORTHWARD INTO CENTRAL CALIFORNIA. THE 18Z NAM-12
FORECASTS NEAR SATURATION OF THE 700-500-MB LAYER OVER THE SOUTHERN
SIERRA NEVADA...TEHACHAPI MOUNTAINS AND KERN DESERT AREAS BY 15Z
/0800 PDT/ MONDAY WITH DRIER AIR MOVING INTO THE REGION FROM THE
SOUTH TUESDAY. WITH PARTIAL CLEARING TUESDAY...TEMPERATURES SHOULD
BE A COUPLE OF DEGREES WARMER THAN MONDAY.
AFTER MONDAY...THUNDERSTORMS ARE FORECAST TO BE CONFINED TO THE
HIGHER ELEVATIONS OF THE SOUTHERN SIERRA NEVADA THROUGH THE END OF
THE WEEK. THE ECMWF FORECASTS LITTLE CHANGE IN 850-MB TEMPERATURES
OVER THE CENTRAL SAN JOAQUIN VALLEY THROUGH MID-WEEK...THEN A SLIGHT
COOLING TREND AS AN UPPER-LEVEL TROUGH APPROACHES THE PACIFIC
NORTHWEST AND WEAKENS THE RIDGE. THE LATEST GFS...IN CONTRAST TO
BOTH THE ECMWF AND PREVIOUS GFS RUNS...PICKS UP ON THE COOLING FOR
MONDAY...THEN WARMS 850-MB TEMPERATURES TUESDAY THROUGH FRIDAY
BEFORE A BRIEF COOL-DOWN SATURDAY.
DESPITE THE MODEL DIFFERENCES...THE FORECAST OF 850-MB TEMPERATURES
MOSTLY BETWEEN 25-26 C OVER THE CENTRAL SAN JOAQUIN VALLEY FOR MUCH
OF THE COMING WEEK SUGGESTS THAT THE CENTRAL AND SOUTHERN SAN
JOAQUIN VALLEY LIKELY WILL SEE TEMPERATURES RUNNING A FEW DEGREES
ABOVE NORMAL THROUGH THE START OF AUGUST.
&&
.AVIATION...
ISOLATED THUNDERSTORMS CAN BE EXPECTED ALONG THE SIERRA CREST
UNTIL 04Z MONDAY WITH A RECURRENCE AFTER 19Z MONDAY. OTHERWISE...
VFR CONDITIONS WILL PREVAIL THROUGHOUT THE CENTRAL CALIFORNIA
INTERIOR DURING THE NEXT 24 HOURS.
&&
.AIR QUALITY ISSUES...
ON SUNDAY JULY 27 2014... UNHEALTHY FOR SENSITIVE GROUPS IN FRESNO
AND MADERA COUNTIES.
FURTHER INFORMATION IS AVAILABLE AT VALLEYAIR.ORG
&&
.CERTAINTY...
THE LEVEL OF CERTAINTY FOR DAYS 1 AND 2 IS HIGH.
THE LEVEL OF CERTAINTY FOR DAYS 3 THROUGH 7 IS MEDIUM.
CERTAINTY LEVELS INCLUDE LOW...MEDIUM...AND HIGH. PLEASE VISIT
WWW.WEATHER.GOV/HNX/CERTAINTY.PHP /ALL LOWER CASE/ FOR ADDITIONAL
INFORMATION AND/OR TO PROVIDE FEEDBACK.
&&
.CLIMATE...
RECORDS
SITE DATE HI_MAX:YEAR LO_MAX:YEAR HI_MIN:YEAR LO_MIN:YEAR
KFAT 07-27 114:1933 83:1941 79:1933 52:1897
KFAT 07-28 110:1980 89:1941 82:1980 55:1892
KFAT 07-29 113:1898 87:1896 78:2003 57:1950
KBFL 07-27 117:1933 85:1965 83:1980 52:1914
KBFL 07-28 118:1908 85:1941 84:1931 50:1914
KBFL 07-29 114:1908 87:1965 86:2003 52:1914
&&
.HNX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
PUBLIC...SANGER
AVN/FW...DURFEE
SYNOPSIS...ANDERSEN
WEATHER.GOV/HANFORD
SOUTHWEST CALIFORNIA AREA FORECAST DISCUSSION
NWS LOS ANGELES/OXNARD CA
1050 AM PDT SUN JUL 27 2014
...AVIATION DISCUSSION UPDATED...
.SYNOPSIS...MONSOONAL MOISTURE WILL BRING A SLIGHT CHANCE OF SHOWERS
AND THUNDERSTORMS TO THE MOUNTAINS OF SANTA BARBARA AND VENTURA
COUNTIES AND MOST OF LOS ANGELES COUNTY TODAY...WITH A LINGERING
SLIGHT CHANCE IN THE MOUNTAINS AND ANTELOPE VALLEY MONDAY.
OTHERWISE...HIGH PRESSURE JUST TO THE EAST OF THE REGION WILL KEEP
TEMPERATURES GENERALLY ABOVE NORMAL THROUGH THE WEEK. NIGHT THROUGH
MORNING LOW CLOUDS AND FOG WILL REMAIN CONFINED MOSTLY TO THE
COASTAL PLAIN.
&&
.SHORT TERM (TODAY-TUE)...LATEST GUIDANCE INITIALIZED REASONABLY
WELL AND DIFFERED SLIGHTLY FROM PREVIOUS RUNS AT INITIALIZATION
TIME. THE AREA OF THUNDERSTORMS MOVING NORTH AND SKIRTING THE FAR
NORTHWEST PORTION OF THE COASTAL WATERS WAS ASSOCIATED WITH A WIDE
AREA OF MIDDLE LEVEL CAPE AND THE AREA WILL CONTINUE MOVING NORTH
AND DECREASE THROUGH THE MORNING. THE BROKEN/OVERCAST MID LEVEL
MOSITURE FIELD CURRENTLY PROPAGATING NORTHWEST OVER LOS
ANGELES/VENTURA COUNTIES IS EXPECTED TO CONTINUE SHIFTING NORTHWEST
AND BECOME SCATTERED TO BROKEN THROUGH THE MID AFTERNOON. MOISTURE
ORIGINATING FROM THE CONVECTIVE ACTIVITY OVER NORTHERN BAJA IS
EXPECTED TO INCREASE OVER AREA THIS EVENING WITH BROKEN/OVERCAST
SKIES OVER SANTA BARBARA COUNTY. OTHERWISE THE LATEST RUC INDICATED
THE BULK OF THE CONVECTIVE ACTIVITY EAST OF THE AREA FROM APPLE
VALLEY AND EXTENDING SOUTH. THUNDERSTORMS WILL MOVE EAST SLOWLY AND
THE OUTFLOW FROM STORMS IN APPLE VALLEY MAY INITIATE SCATTERED
THUNDERSTORMS IN THE ANTELOPE VALLEY THIS AFTERNOON THROUGH EARLY
EVENING.
THE FOLLOWING IS AN EXCERPT FROM THE PREVIOUS DISCUSSION.
IF TSTMS DO DEVELOP...FAIRLY JUICY PRECIPITABLE WATER VALUES AND
SOME INCREASE IN LOW LEVEL MOISTURE SUGGEST THAT THERE COULD BE
LOCALLY HEAVY RAIN...PARTICULARLY IN HIGHER ELEVATIONS. STEERING
FLOW IS GENERALLY WEAK...BUT ONLY MARGINALLY SO...SO THE THREAT OF
FLASH FLOODING WILL BE SOMEWHERE ON THE BORDER OF LOW AND MODERATE.
THE GFS INDICATES SOME LINGERING MOISTURE TONIGHT WITH ANOTHER VORT
SWINGING INTO THE REGION. FOR NOW...KEPT POPS BELOW SLIGHT CHANCE
AFTER THIS EVENING...BUT IT IS POSSIBLE THEY MAY HAVE TO BE EXTENDED
IN SOME AREAS. OTHERWISE...EXPECT NIGHT THROUGH MORNING LOW CLOUDS
AND FOG TO BECOME A BIT MORE WIDESPREAD IN COASTAL AREAS...
ESPECIALLY IF MID LEVEL MOISTURE DECREASES.
THE UPPER HIGH WILL REMAIN JUST TO THE SOUTH OF THE FOUR CORNERS
AREA THROUGH TUE. IT NOW LOOKS AS THROUGH THERE WILL BE ENOUGH
LINGERING MOISTURE FOR A SLIGHT CHANCE OF SHOWERS AND TSTMS IN THE
MTNS OF SBA...VTU AND L.A. COUNTIES AND THE ANTELOPE VALLEY MONDAY
AFTERNOON AND EVENING. WHILE MID LEVEL FLOW WILL BE EVEN WEAKER THAN
IT IS TODAY...PRECIPITABLE WATER VALUES WILL BE DOWN SOME...SO THE
THREAT OF FLASH FLOODING IF ANY STORMS DEVELOP SHOULD BE A BIT
LOWER. MAX TEMPS SHOULD BE SIMILAR TO THOSE OF TODAY...ALTHOUGH THEY
COULD BE A FEW DEGREES HIGHER ACROSS L.A. AND VTU COUNTIES IF CLOUD
COVER TODAY KEEPS TEMPS DOWN.
NIGHT THROUGH MORNING LOW CLOUDS AND FOG WILL REMAIN CONFINED TO THE
COASTAL PLAIN MON NIGHT AND TUE...AND TEMPS WILL GENERALLY REMAIN A
FEW DEGREES ABOVE NORMAL. AT THIS POINT...IT APPEARS THAT THERE WILL
BE NO REAL CHANCE OF SHOWERS/TSTMS ACROSS THE REGION TUE.
.LONG TERM (WED-SAT)...THE UPPER PATTERN WILL CHANGE LITTLE THROUGH
THE PERIOD...WITH A RATHER STRONG UPPER HIGH OVER NEW MEXICO AND
ARIZONA...AND FAIRLY HIGH HEIGHTS/THICKNESSES ACROSS THE REGION.
EXPECT THE MARINE LAYER TO REMAIN RATHER SHALLOW...WITH NIGHT
THROUGH MORNING LOW CLOUDS AND FOG LIKELY CONFINED TO THE COASTAL
PLAIN AND POSSIBLY THE LOWER VLY LOCATIONS. TEMPS ARE EXPECTED TO
REMAIN A FEW DEGREES ABOVE NORMAL THROUGH THE PD.
&&
.AVIATION...27/18Z
MODERATE CONFIDENCE IN THE 18Z TAFS WITH THE REDUCED CONFIDENCE DUE
TO DEVELOPING CONVECTIVE ENVIRONMENT AND DUE TO UNCERTAINTY WITH THE
MARINE LAYER LOCATION... INTENSITY... AND DURATION. PRIMARY CONCERN
TODAY WILL BE THE DEVELOPMENT AND MOVEMENT OF SHOWERS AND
THUNDERSTORMS THROUGH THE SERVICE AREA. THESE WILL PRIMARILY AFFECT
LOCATIONS SOUTH OF POINT CONCEPTION PERIODICALLY TODAY THROUGH
MONDAY THOUGH WOULD NOT RULE OUT POSSIBILITY OF SOME MOVING ACROSS
THE ENTIRE REGION. THE MARINE LAYER WILL RETURN TONIGHT BUT WITH
HIGH CLOUD COVER IT SHOULD NOT BE AS INTENSE AND UNIFORM AS IT WAS
THIS MORNING.
KLAX...LOW TO MODERATE CONFIDENCE IN THE 18Z TAF. THUNDERSTORMS
WILL BE IN THE VICINITY OF THE AIRPORT BUT THEY ARE WIDELY SPACED
ENOUGH TO BE UNCERTAIN AS TO IF THEY WILL MOVE DIRECTLY OVER THE
LOCATION. PRIMARY TIMING OF THE FIRST WAVE OF THUNDERSTORMS WILL BE
THROUGH 23Z BUT THEY ARE POSSIBLE PERIODICALLY THROUGH MONDAY. THE
MARINE LAYER WILL REFORM TONIGHT BUT WITH LESS INTENSITY AND
UNIFORMITY.
KBUR...LOW TO MODERATE CONFIDENCE IN THE 18Z TAF. THUNDERSTORMS
WILL BE IN THE VICINITY OF THE AIRPORT BUT THEY ARE WIDELY SPACED
ENOUGH TO BE UNCERTAIN AS TO IF THEY WILL MOVE DIRECTLY OVER THE
LOCATION. PRIMARY TIMING OF THE FIRST WAVE OF THUNDERSTORMS WILL BE
THROUGH 23Z BUT THEY ARE POSSIBLE PERIODICALLY THROUGH MONDAY.
&&
.MARINE...27/900 AM
A SLIGHT CHANCE OF THUNDERSTORMS IN THE SOUTHERN COASTAL WATERS
TODAY AND IN THE VICINITY ON MONDAY... WITH LOCALLY STRONG AND GUSTY
WINDS POSSIBLE. OTHERWISE WEAK TO LOCALLY MODERATE WINDS ACROSS THE
COASTAL WATERS INTO NEXT WEEK.
&&
.LOX WATCHES/WARNINGS/ADVISORIES...
MARINE WEATHER STATEMENT (SEE LAXMWSLOX).
&&
$$
PUBLIC...30/DB
AVIATION...KJ
MARINE...KJ
WWW.WEATHER.GOV/LOSANGELES
SOUTHWEST CALIFORNIA AREA FORECAST DISCUSSION
NWS LOS ANGELES/OXNARD CA
915 AM PDT SUN JUL 27 2014
.SYNOPSIS...MONSOONAL MOISTURE WILL BRING A SLIGHT CHANCE OF SHOWERS
AND THUNDERSTORMS TO THE MOUNTAINS OF SANTA BARBARA AND VENTURA
COUNTIES AND MOST OF LOS ANGELES COUNTY TODAY...WITH A LINGERING
SLIGHT CHANCE IN THE MOUNTAINS AND ANTELOPE VALLEY MONDAY.
OTHERWISE...HIGH PRESSURE JUST TO THE EAST OF THE REGION WILL KEEP
TEMPERATURES GENERALLY ABOVE NORMAL THROUGH THE WEEK. NIGHT THROUGH
MORNING LOW CLOUDS AND FOG WILL REMAIN CONFINED MOSTLY TO THE
COASTAL PLAIN.
&&
.SHORT TERM (TODAY-TUE)...LATEST GUIDANCE INITIALIZED REASONABLY
WELL AND DIFFERED SLIGHTLY FROM PREVIOUS RUNS AT INITIALIZATION
TIME. THE AREA OF THUNDERSTORMS MOVING NORTH AND SKIRTING THE FAR
NORTHWEST PORTION OF THE COASTAL WATERS WAS ASSOCIATED WITH A WIDE
AREA OF MIDDLE LEVEL CAPE AND THE AREA WILL CONTINUE MOVING NORTH
AND DECREASE THROUGH THE MORNING. THE BROKEN/OVERCAST MID LEVEL
MOSITURE FIELD CURRENTLY PROPAGATING NORTHWEST OVER LOS
ANGELES/VENTURA COUNTIES IS EXPECTED TO CONTINUE SHIFTING NORTHWEST
AND BECOME SCATTERED TO BROKEN THROUGH THE MID AFTERNOON. MOISTURE
ORIGINATING FROM THE CONVECTIVE ACTIVITY OVER NORTHERN BAJA IS
EXPECTED TO INCREASE OVER AREA THIS EVENING WITH BROKEN/OVERCAST
SKIES OVER SANTA BARBARA COUNTY. OTHERWISE THE LATEST RUC INDICATED
THE BULK OF THE CONVECTIVE ACTIVITY EAST OF THE AREA FROM APPLE
VALLEY AND EXTENDING SOUTH. THUNDERSTORMS WILL MOVE EAST SLOWLY AND
THE OUTFLOW FROM STORMS IN APPLE VALLEY MAY INITIATE SCATTERED
THUNDERSTORMS IN THE ANTELOPE VALLEY THIS AFTERNOON THROUGH EARLY
EVENING.
THE FOLLOWING IS AN EXCERPT FROM THE PREVIOUS DISCUSSION.
IF TSTMS DO DEVELOP...FAIRLY JUICY PRECIPITABLE WATER VALUES AND
SOME INCREASE IN LOW LEVEL MOISTURE SUGGEST THAT THERE COULD BE
LOCALLY HEAVY RAIN...PARTICULARLY IN HIGHER ELEVATIONS. STEERING
FLOW IS GENERALLY WEAK...BUT ONLY MARGINALLY SO...SO THE THREAT OF
FLASH FLOODING WILL BE SOMEWHERE ON THE BORDER OF LOW AND MODERATE.
THE GFS INDICATES SOME LINGERING MOISTURE TONIGHT WITH ANOTHER VORT
SWINGING INTO THE REGION. FOR NOW...KEPT POPS BELOW SLIGHT CHANCE
AFTER THIS EVENING...BUT IT IS POSSIBLE THEY MAY HAVE TO BE EXTENDED
IN SOME AREAS. OTHERWISE...EXPECT NIGHT THROUGH MORNING LOW CLOUDS
AND FOG TO BECOME A BIT MORE WIDESPREAD IN COASTAL AREAS...
ESPECIALLY IF MID LEVEL MOISTURE DECREASES.
THE UPPER HIGH WILL REMAIN JUST TO THE SOUTH OF THE FOUR CORNERS
AREA THROUGH TUE. IT NOW LOOKS AS THROUGH THERE WILL BE ENOUGH
LINGERING MOISTURE FOR A SLIGHT CHANCE OF SHOWERS AND TSTMS IN THE
MTNS OF SBA...VTU AND L.A. COUNTIES AND THE ANTELOPE VALLEY MONDAY
AFTERNOON AND EVENING. WHILE MID LEVEL FLOW WILL BE EVEN WEAKER THAN
IT IS TODAY...PRECIPITABLE WATER VALUES WILL BE DOWN SOME...SO THE
THREAT OF FLASH FLOODING IF ANY STORMS DEVELOP SHOULD BE A BIT
LOWER. MAX TEMPS SHOULD BE SIMILAR TO THOSE OF TODAY...ALTHOUGH THEY
COULD BE A FEW DEGREES HIGHER ACROSS L.A. AND VTU COUNTIES IF CLOUD
COVER TODAY KEEPS TEMPS DOWN.
NIGHT THROUGH MORNING LOW CLOUDS AND FOG WILL REMAIN CONFINED TO THE
COASTAL PLAIN MON NIGHT AND TUE...AND TEMPS WILL GENERALLY REMAIN A
FEW DEGREES ABOVE NORMAL. AT THIS POINT...IT APPEARS THAT THERE WILL
BE NO REAL CHANCE OF SHOWERS/TSTMS ACROSS THE REGION TUE.
.LONG TERM (WED-SAT)...THE UPPER PATTERN WILL CHANGE LITTLE THROUGH
THE PERIOD...WITH A RATHER STRONG UPPER HIGH OVER NEW MEXICO AND
ARIZONA...AND FAIRLY HIGH HEIGHTS/THICKNESSES ACROSS THE REGION.
EXPECT THE MARINE LAYER TO REMAIN RATHER SHALLOW...WITH NIGHT
THROUGH MORNING LOW CLOUDS AND FOG LIKELY CONFINED TO THE COASTAL
PLAIN AND POSSIBLY THE LOWER VLY LOCATIONS. TEMPS ARE EXPECTED TO
REMAIN A FEW DEGREES ABOVE NORMAL THROUGH THE PD.
&&
.AVIATION...
27/1145Z
MARINE LAYER IS 800 FEET DEEP AND STRATUS COVERS MOST OF THE COAST.
LOW CONFIDENCE IN COASTAL TAFS AS BURN OFF WILL BE VERY HAPHAZARD
DUE TO THE OVERRUNNING MID AND HIGH CLOUDS. THERE IS A 20 PERCENT
CHC OF A THUNDERSTORM OVER LOS ANGELES AND VENTURA COUNTIES THROUGH
THE EVENING. MARINE LAYER WILL FORM IN A RANDOM MANOR TONIGHT.
KLAX...LOW CONFIDENCE IN TAF WITH BURN OFF POSSIBLE ANYTIME FROM 16Z
TO 20Z. THERE IS A 20 PERCENT CHANCE OF A THUNDERSTORM FROM 15Z TO
04Z.
KBUR...GOOD CONFIDENCE IN TAF. THERE IS A 20 PERCENT CHANCE OF A
THUNDERSTORM FROM 15Z TO 04Z.
&&
.MARINE...
27/900 AM
A SLIGHT CHANCE OF THUNDERSTORMS IN THE SOUTHERN COASTAL WATERS
TODAY AND IN THE VICINITY ON MONDAY... WITH LOCALLY STRONG AND GUSTY
WINDS POSSIBLE. OTHERWISE WEAK TO LOCALLY MODERATE WINDS ACROSS THE
COASTAL WATERS INTO NEXT WEEK.
&&
.LOX WATCHES/WARNINGS/ADVISORIES...
NONE
&&
$$
PUBLIC...30/DB
AVIATION...RORKE
MARINE...KJ
WWW.WEATHER.GOV/LOSANGELES
AREA FORECAST DISCUSSION
NWS PUEBLO CO
223 PM MDT SUN JUL 27 2014
.SHORT TERM...(THIS EVENING THROUGH MONDAY)
ISSUED AT 203 PM MDT SUN JUL 27 2014
MONSOON MSTR WL CONTINUE STREAMING OVR THE AREA TONIGHT AND
MONDAY...AND GOOD LOW LEVEL MSTR AND UPSLOPE FLOW IS IN PLACE. DEW
POINTS OVR THE SERN PLAINS ARE IN THE LOWER 60S IN MOST AREAS...WITH
MID 50S AT 1 PM OVR THE SRN I-25 CORRIDOR AROUND WALSENBURG AND
TRINIDAD.
00Z WRF FORECAST HAS SIGNIFICANT RAIN AMOUNTS MOVING OUT OVR
PORTIONS OF THE SERN PLAINS THIS EVENING AND INTO THE LATE NIGHT
HOURS...MAINLY FROM THE I-25 CORRIDOR...EASTWARD TO BENT COUNTY AND
THEN ALONG THE SRN PLAINS (LAS ANIMAS AND BACA COUNTIES).
HOWEVER...THE 12Z RUN OF THE HRRR...THE RAP...NAM AND ARW HAVE
BACKED OFF OF PCPN ACRS THE SERN PLAINS...EXCEPT ALONG THE I-25
CORRIDOR...WHERE THE HRRR HITS ERN FREMONT AND THE WRN HALF OF
PUEBLO COUNTY HARD WITH PCPN THIS EVENING. THE GFS ALSO FAVORS THE
I-25 CORRIDOR SOUTH OF PUEBLO WITH AROUND 0.50. THE 18Z RAP IS NOW
TRENDING TOWARD MORE PCPN AGAIN OVR THE SERN PLAINS...ALTHOUGH IT IS
NOT ALL THAT SIGNIFICANT WITH A FEW TENTHS. OVERALL...THE FLASH
FLOOD THREAT AREA IS GENERALLY COVERED WELL WITH THE CURRENT FLASH
FLOOD WATCH. HOWEVER...IT IS POSSIBLE THAT SIGNIFICANT RAINFALL MAY
NOT OCCUR EAST OF THE I-25 CORRIDOR COUNTIES. BUT GIVEN THAT THERE
IS SOME UNCERTAINTY...WL NOT MAKE CHANGES TO THE AREAL COVERAGE OF
THAT WATCH. THE RAP KEEPS SOME LIGHT LINGERING PCPN OVR THE FAR
SERN PLAINS THRU THE NIGHT...WHILE THE NAM AND ARW DO NOT...HAVE
DECIDED TO KEEP SOME ISOLD POPS IN THAT AREA TO MATCH SURROUNDING
WFO/S.
SIMILAR CONDITIONS WL BE IN PLACE ON MONDAY AND THE NAM AND ARW SHOW
CONVECTION FIRING UP BY MID TO LATE MORNING...WITH GOOD COVERAGE OVR
THE MTNS AND I-25 CORRIDOR IN THE AFTERNOON HOURS. BY LATE
AFTERNOON OR EARLY EVENING SOME SCT PCPN IS THEN EXPECTED TO SPREAD
OVR THE SERN PLAINS. AGAIN...THE BEST CHANCES FOR SIGNIFICANT
RAINFALL IS EXPECTED TO BE ALONG THE ERN MTNS AND I-25 CORRIDOR AND
A FLASH FLOOD WATCH MAY BE NEEDED. WL NOT ISSUE THE WATCH AT THIS
TIME...WL LET LATER SHIFTS SEE WHERE THE HEAVY RAIN FALLS TODAY.
.LONG TERM...(MONDAY NIGHT THROUGH SUNDAY)
ISSUED AT 203 PM MDT SUN JUL 27 2014
...RISK OF FLOODING THROUGH THE WEEK...
WELL-ADVERTISED HEAVY RAIN PATTERN WILL CONTINUE TO DEVELOP
OVER THE NEXT COUPLE OF DAYS...AS THE MONSOON KICKS INTO HIGH
GEAR AND STAYS THERE FOR THE NEXT WEEK OR SO.
MON NIGHT...THREAT SHOULD WIND DOWN AFTER SUNSET WITH LOSS OF
HEATING FOR MOST OF THE CWA. EXCEPTION MAY BE NR THE CO-KS
BORDER WHERE ANOTHER MCS MAY DEVELOP AND FEED ON A LOW LEVEL
JET MOVING NWD THROUGH THE PANHANDLES. TEMPS WILL CONTINUE TO
BE BELOW AVERAGE...LIKELY ONLY HITTING THE LOWER 80S FOR HIGHS
ACROSS THE PLAINS.
TUE-WED...LOOK LIKE THE WETTEST DAYS WITH THE GREATEST THREAT
OF WIDESPREAD FLOODING. HPC HAS ALREADY PUT OUR AREA IN A
MODERATE RISK FOR EXCESSIVE RAINFALL. THE MAIN PLAYER WILL BE A
SHORT WAVE TROUGH EMBEDDED IN THE NW FLOW ON THE NE SIDE OF THE
MONSOONAL HIGH. MODELS DIFFER ON THE STRENGTH OF THIS SYSTEM...BUT
REGARDLESS IT WILL BE STRONG ENOUGH TO SPARK NUMEROUS SHOWERS
AND STORMS DURING THIS TIME PERIOD...WITH THE GREATEST THREAT
IN THE LATE TUE AFTERNOON THROUGH WED AFTERNOON TIME FRAME.
PREC H2O CONTINUES TO BE IN THE 1-1.5 INCH RANGE...WITH DEEP
MOISTURE PUSHING UP THE ARKANSAS RIVER VALLEY TUE NIGHT.
PRETTY MUCH ALL OF SE CO WILL BE UNDER THE GUN FOR FLASH
FLOODING...WITH RECENT RAINFALL DETERMINING THE HIGHER THREAT
AREAS...ALONG WITH THE USUAL TARGETS SUCH AS BURN SCARS AND
URBAN AREAS. THERE WILL ALSO BE A THREAT OF SOME SVR STORMS
FOR THE ERN BORDER COUNTIES LATE TUE AFTERNOON THROUGH TUE
EVE...AS THE SHORTWAVE RESULTS IN BULK SHEARS IN THE 40 KT
RANGE...WHICH ALONG WITH HIGH CAPE COULD BE A RECIPE FOR SOME SVR
WX DEPENDING ON HOW THE MESOSCALE PRECIP PATTERN SETS UP.
THU ONWARD...THE HEAVIEST WIDESPREAD RAIN SHOULD WIND DOWN...BUT
THERE WILL STILL BE SIGNIFICANT MONSOONAL MOISTURE AROUND. STORMS
SHOULD STILL BE PRETTY NUMEROUS OVER THE MT AREAS ON A DIURNAL
BASIS. MCS ACTIVITY OVER THE PLAINS WILL LIKELY SHIFT A BIT TO THE
E...BUT MAY STILL AFFECT PORTIONS OF THE PLAINS. TEMPS CONTINUE TO
BE MORE LIKE SEPTEMBER FOR THE AREA...GENERALLY IN THE 70S-80S.
ROSE
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON)
ISSUED AT 203 PM MDT SUN JUL 27 2014
CHANCES FOR SHOWERS AND TSTMS WL CONTINUE AT OR IN THE VCNTY OF
KCOS...KPUB AND KALS THROUGH ABOUT 06Z. HEAVY RAIN WL BE POSSIBLE
AND COULD BRIEFLY CAUSE MVFR OR EVEN IFR CONDITIONS. THERE COULD
BE SOME STRATUS IN THE EARLY MORNING HOURS. SHOWERS AND TSTMS WL
AGAIN DEVELOP IN THE LATE MORNING OR EARLY AFTERNOON HOURS ON
MONDAY...WITH HEAVY RAIN AGAIN BEING THE MAIN THREAT.
&&
.PUB WATCHES/WARNINGS/ADVISORIES...
FLASH FLOOD WATCH UNTIL 9 PM MDT THIS EVENING FOR COZ076>078-
081>086-089-093-097.
FLASH FLOOD WATCH UNTIL MIDNIGHT MDT TONIGHT FOR COZ072>075-079-
080-087-088-094-099.
&&
$$
SHORT TERM...28
LONG TERM...ROSE
AVIATION...28
AREA FORECAST DISCUSSION
NWS MOUNT HOLLY NJ
334 PM EDT SUN JUL 27 2014
.SYNOPSIS...
AN AREA OF LOW PRESSURE WILL MOVE OUT OF PENNSYLVANIA TONIGHT AND
LIFT INTO NEW ENGLAND MONDAY, PULLING A COLD FRONT ACROSS THE AREA.
HIGH PRESSURE WILL BEGIN MOVING INTO THE AREA LATER TUESDAY, AND
REMAIN IN CONTROL OF THE WEATHER FOR THROUGH THE END OF THE UPCOMING
WEEK.
&&
.NEAR TERM /UNTIL 6 AM MONDAY MORNING/...
THE GFS INITIALIZATION CONTINUES TO LOOK SLIGHTLY BETTER AT 500MB
BUT ITS CONVECTIVE FEEDBACK OF VORT MAXES WHILE ON ONE LEVEL
CORRECT CONTINUE TO MAKE IT DIFFICULT TO FOLLOW THE MODEL. NEAR AND
SHORT TERM SOLUTION ARE AN ECMWF/HI RES ARW BLEND AS THE FORMER HAS
VERIFIED THE SYNOPTIC SCALE SHORT WAVES BETTER AND THE LATTER WAS
USED FOR CONVECTIVE ADJUSTMENTS AS ITS VERIFYING WELL AT 18Z.
COSPA VERIFYING TOO SLOW WITH CONVECTION LEAVING OHIO AND TOO NORTH
WITH WV CONVECTION. IT...RAP AND HRRR ALL DEVELOP CONVECTION OVER
THE ALLEGHENIES AND ADVECT IT EAST AHEAD OF ONGOING CONVECTION OVER
OH/PA BORDER ASSOCIATED WITH THE STRONG SHORT WAVE. SPC ANALYSIS IS
SHOWING 2000J ML CAPE IN THAT AREA AND THE STABILITY OF WAVE CLOUDS
ON VIS SATL OVER THAT AREA IS NOW GONE. SO WE WILL CONT TO START
GRIDS WITH LOW POPS THAT WILL INCREASE WITH TIME THIS EVENING.
POPS ARE TIED CLOSE TO THE ARW AND ALSO THE DEEPER LAYER MASS OMEGA
FIELDS BY THE MODELS. IN SPITE OF QPF TIMING DIFFERENCES, THE OMEGA
FIELDS TIMING ARE CLUSTERED CLOSER. THIS REMAINS A DYNAMIC SCENARIO
WITH A NEGATIVE TILT TROF AND EVEN A JET COUPLET OVER OUR CWA FOR A
WHILE OVERNIGHT. EVENTUALLY THE MLCAPE WILL DECREASE, EVEN THOUGH
THERE WILL BE NO END TO THE PREDICTED BULK SHEAR AVERAGING AROUND
40KTS. SO THE STRONGER (SEVERE?) POTENTIAL WITH THE THUNDER MAY
LINGER LONGER INTO THE NIGHT. LAST COUPLE OF COSPAS DONT CORROBORATE
THIS. FOR NOW, WE CARRIED SOME ENHANCED WORDING PAST MIDNIGHT. GIVEN
THE NEGATIVE TILT FLAVOR OF THE TROF, WHILE RAIN WILL BE HEAVY, IT
SHOULD BE PROGRESSIVE. WITH FFG VALUES RUNNING AT TYPICALLY HIGH
SUMMER LEVELS, SEVERE THREAT REMAINS OUR MORE FOCUSED CONCERN.
WE WERE SLOW WITH DROPPING TEMPS THIS EVENING AND TRIED TO TIME THE
DROP TO THE ONSET OF HEAVIER RAIN. MIN TEMPS NOT THAT FAR FROM STAT
GUIDANCE.
&&
.SHORT TERM /6 AM MONDAY MORNING THROUGH 6 PM MONDAY/...
SHORT WAVES ROTATING AROUND THE ANOMALOUS STRONG 500MB TROF WILL
PASS ACROSS OUR CWA ON MONDAY. CONVECTIVE TEMPS (SELF DESTRUCT
SUNSHINE) WILL BE REACHED EASY AND EARLY. THE OVERALL FCST CAPE AND
INSTAB ALOFT ON THE BIG THREE MODELS ARE NOT UNSTABLE ENOUGH FOR
THUNDER. OTHER THAN SOME EARLY THUNDER NORTHEAST CWA, WE KEPT IT AS
SHOWERS WITH HIGHEST POPS NORTHWEST THE REST OF THE DAY.
STAT GUIDANCE FOR MAX TEMPS APPEARS TOO HIGH IN THE SERN CWA UNLESS
THE COLD FRONT IS 2-4HRS SLOWER THAN PROGGED. WE WERE LOWER THAN GFS
MOS THERE AND CLOSE TO A STAT GUIDANCE BLEND ELSEWHERE.
&&
.LONG TERM /MONDAY NIGHT THROUGH SUNDAY/...
A MOSTLY DRY START TO THE LONG TERM FORECAST, WITH PRECIPITATION
CHANCES INCREASING LATER IN THE WEEK INTO THE WEEKEND.
THERE MAY BE SOME LINGERING SHOWERS MONDAY EVENING AS THE FRONT
CONTINUES TO PUSH OFFSHORE AND THE MID-LEVEL TROUGH LIFTS OUT, BUT
ANY PRECIPITATION IS EXPECTED TO END BY MIDNIGHT.
MUCH OF THE UPCOMING WEEK IS EXPECTED TO REMAIN MOSTLY DRY AS PW
VALUES DROP TO AN INCH OR LOWER FOR TUESDAY AND WEDNESDAY, BUT MAY
RETURN TO 1-1.25 INCHES FOR THURSDAY AND NEAR 1.5 INCHES FOR FRIDAY.
HIGH PRESSURE AT THE SURFACE WILL BUILD ACROSS THE REGION, WHILE THE
BROAD MID/UPPER TROUGH REMAINS IN PLACE ACROSS MUCH OF THE EASTERN
HALF OF THE COUNTRY. THERE AREA NO SIGNIFICANT SHORT WAVE/VORTICITY
IMPULSES THAT ARE FORECAST TO MOVE THROUGH FOR MUCH OF THE WEEK, BUT
WITH THE TROUGH IN PLACE AND DAYTIME HEATING, THERE COULD BE ENOUGH
DAYTIME INSTABILITY TO CREATE ISOLATED SHOWERS OR THUNDERSHOWERS FOR
THE LATTER HALF OF THE WEEK. EACH DAY THE CHANCES INCREASE SLIGHTLY
AND EXPAND IN COVERAGE. HOWEVER, WE DO NOT HAVE MORE THAN A SLIGHT
CHANCE PROBABILITY THROUGH FRIDAY AT THIS TIME.
AS WE MOVE INTO NEXT WEEKEND, WE GET A MORE SOLID RETURN OF MOISTURE
ACROSS THE AREA AS PW VALUES REBOUND O 1.25-1.5 INCHES. WE ALSO HAVE
A BETTER CHANCE OF VORTICITY IMPULSES AFFECTING OUR AREA WITHIN THE
SOUTHWEST FLOW ALOFT, AND WITH THE COASTAL FRONT TRYING TO PUSH BACK
CLOSER TO SHOWER, WE MAY HAVE A FOCUS FOR PRECIPITATION TO FORM.
THEREFORE THE PRECIPITATION CHANCES INCREASE INTO NEXT WEEKEND.
TEMPERATURES THROUGH THE EXTENDED ARE FORECAST TO BE CLOSE TO OR
SLIGHTLY BELOW NORMAL.
&&
.AVIATION /19Z SUNDAY THROUGH FRIDAY/...
THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG, KILG,
KMIV, KACY AND SURROUNDING AREAS.
18Z TAFS HAVE A HIGH CONVECTIVE IMPACT DURING THIS EVENING INTO
THE EARLY OVERNIGHT ACROSS THE TERMINALS AND AIRPORTS.
REST OF THIS AFTERNOON. VFR WITH CUMULUS CLOUDS EXPANDING AND SOME
CIRRUS ABOVE THEM SOUTH. NO THUNDER MENTIONED ALTHOUGH SOME ISOLATED
THUNDER MIGHT FORM BEFORE THE ORGANIZED SYSTEM. LOWEST CONFIDENCE
ABOUT NO THUNDER IN PA. PLEASE WATCH FOR POSSIBLE AMENDMENTS. WINDS
ARE SLOWLY BACKING TO THE SOUTHWEST AND MAY EVEN GO SOUTH AT SPEEDS
OF AROUND 10 KTS.
THIS EVENING, EXPECTING A LINE OF STRONG TSTMS TO MOVE THROUGH THE
AREA. HIGHEST CONFID AT KABE AND KRDG. LOWEST AT KMIV AND KACY. A
EARLY TIMING HEDGE WAS MAINTAINED (MOST LIKELY TIME IS TOWARD THE
MIDDLE OF THE TEMPO GROUP). MVFR TO BRIEFLY IFR (BECAUSE OF
BREVITY NOT INCLUDED) CONDITIONS LIKELY ALONG WITH GUSTY WEST
WINDS.
OVERNIGHT PREVAILING MVFR CONDITIONS EXPECTED TO CONTINUE DURING
SHOWERS. ISOLATED THUNDER POSSIBLE, BUT CONFIDENCE TOO LOW AS TO
WHERE OR WHEN TO INCLUDE. WINDS WILL BE LIGHTER, GENERALLY FROM
THE SOUTH. IMPROVEMENT TOWARD MORNING AS PCPN ENDS. THINKING TOO
MUCH WIND FOR SGFCNT FOG TO FORM.
MONDAY MORNING, VFR CONDITIONS WITH A CUMULUS BASED CIG OCCURRING.
GUSTY WEST WINDS, ESPECIALLY FOR JULY, WITH SUSTAINED SPEEDS
AROUND 15 KTS AND GUSTS TO AROUND 25 KTS. SOME WIDELY SCATTERED
SHOWERS SHOULD START DEVELOPING TOWARD THE END OF THE CURRENT TAF
FCST PERIOD. GREATEST CONFIDENCE NORTH, REASON FOR NOW LEFT OUT OF
KPHL TAF.
OUTLOOK...
MONDAY NIGHT-WEDNESDAY NIGHT...MAINLY VFR
THURSDAY-FRIDAY...MAINLY VFR. ISOLATED SHOWERS/THUNDERSTORMS
POSSIBLE BOTH AFTERNOONS, ESPECIALLY FRIDAY.
&&
.MARINE...
A SMALL CRAFT ADVISORY WILL BE ISSUED FOR TONIGHT AND MONDAY FOR THE
OCEAN WATERS. ONE WILL BE ISSUED FOR DELAWARE BAY FOR MONDAY. FIRST
FOR THE LIKELIHOOD THAT SEAS REACH 5 FEET THIS EVENING AND THEN THE
LIKELIHOOD OF NON CONVECTIVE WEST WIND GUSTS REACHING THE CRITERIA
ON DELAWARE BAY AS WELL AS THE OCEAN WATERS DURING THE DAY ON
MONDAY. WAVE WATCH GUIDANCE BRINGS SIX FOOT SEAS AS IS INTO OUR
COASTAL WATERS, SHAVING A FOOT OR SO OFF WOULD STILL GET US THERE
TONIGHT. TOUGH NIGHT AS IT IS WITH THUNDERSTORMS EXPECTED. ON MONDAY
MORE OF THE GUSTINESS MAY BE CONCENTRATED AROUND THE INLETS AND IN
DELAWARE BAY WITH POSSIBLY LESS GUSTINESS FARTHER OFFSHORE. THE
GRADIENT AND WINDS SHOULD START RELAXING LATER IN THE DAY ON MONDAY.
OUTLOOK...
MONDAY NIGHT-FRIDAY...SMALL CRAFT ADVISORY CONDITIONS POSSIBLE EARLY
MONDAY NIGHT, SUBSIDING AND REMAINING BELOW ADVISORY LEVELS THROUGH
THE PERIOD.
&&
.PHI WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NJ...NONE.
DE...NONE.
MD...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...ROBERTSON
NEAR TERM...GIGI
SHORT TERM...GIGI
LONG TERM...ROBERTSON
AVIATION...GIGI/ROBERTSON
MARINE...GIGI/ROBERTSON
AREA FORECAST DISCUSSION
NWS PEACHTREE CITY GA
321 PM EDT SUN JUL 27 2014
.SHORT TERM /TONIGHT THROUGH MONDAY NIGHT/...
HIGH PRESSURE WILL CONTINUE ACROSS THE NORTH CENTRAL GULF OF MEXICO
THIS EVENING. A COLD FRONT CURRENTLY STRETCHES FROM THE CENTRAL
GREAT LAKES BACK THROUGH THE CENTRAL PLAINS STATES. THE FRONT WILL
DROP SOUTH OVERNIGHT AND BEGIN APPROACHING THE CWFA BY SUNRISE
MONDAY.
MODELS HAVE BEEN CONSISTENT WITH PRODUCING CONVECTION ALONG THE
TN/GA BORDER OVERNIGHT. THIS SEEMS REASONABLE...AS ANY LEFT OVER
CONVECTION FROM LATE THIS AFTERNOON/EVENING IS PROGGED TO DROP SOUTH
ACROSS TN. LATEST RUNS OF THE HRRR HAVE THE SHOWERS AND
THUNDERSTORMS MOVING INTO NORTHERN GA BETWEEN 06Z AND 08Z. THE
STORMS SHOULD WEAKEN AS THEY GET AWAY FROM THE BEST MID LEVEL
FORCING AND DYNAMICS.
ADDITIONAL STORMS ARE EXPECTED TO DEVELOP BY THE EARLY AFTERNOON
ALONG THE FRONT AND/OR ANY LEFTOVER OUTFLOW BOUNDARY FROM THE EARLY
MORNING CONVECTION. IF THE EARLY MORNING CONVECTION PRODUCES ENOUGH
BLOW OFF TO LIMIT HEATING ACROSS THE SOUTHERN HALF OF THE
CWFA...THUNDERSTORM SEVERITY AND COVERAGE WILL BE LIMITED.
HOWEVER...IF GOOD HEATING IS REALIZED...THE POTENTIAL FOR SEVERE
THUNDERSTORMS WILL BE HIGHER. ANY SEVERE THUNDERSTORM THAT DEVELOPS
WILL HAVE THE POTENTIAL TO PRODUCING DAMAGING WIND GUSTS AND LARGE
HAIL. LOCALLY HEAVY RAINFALL WILL ALSO BE POSSIBLE.
MODELS HAVE ALSO BEEN CONSISTENT WITH MOVING THE DRY AIR IN BEHIND
THE FRONT RATHER QUICKLY. SO...RAPID CLEARING WILL BE POSSIBLE
ACROSS THE NORTHERN CWFA BY MID AFTERNOON. ONLY SOME LINGERING
ACTIVITY IS EXPECTED ACROSS THE FAR SOUTH DURING THE EARLY
EVENING...WITH THE OVERNIGHT HOURS EXPECTED DRY.
NLISTEMAA
.LONG TERM /TUESDAY THROUGH SUNDAY/...
MAINLY ONLY TWEAKS TO THE LONG TERM BASED ON THE LATEST GUIDANCE.
WITH THE MUCH COOLER AIRMASS BEHIND THE NEXT COLD FRONT...SOME LOW
TEMPERATURE RECORDS WITH BE THREATENED WEDNESDAY MORNING AND POSSIBLY
AT CSG THURSDAY MORNING. TUESDAY MORNING LOWS WITH BE WITHIN 3-5
DEGREES OF THE RECORD LOWS FOR THAT DAY. LEANED HARD ON WPC HIGH/LOW
TEMPERATURES AND POPS FOR WEDNESDAY AND BEYOND.
BDL
PREVIOUS DISCUSSION...
THE FRONTAL BOUNDARY THAT AFFECTS THE STATE MONDAY WILL BE SOUTH OF
THE CWA BY 12Z TUE. THIS FRONTAL PASSAGE USHERS IN A AN UPPER LEVEL
DEEP LONG WAVE TROUGH WHICH REMAINS POSITIONED OVER THE AREA THROUGH
MUCH OF NEXT WEEK...KEEPING LOWER DEW POINTS AND COOLER TEMPERATURES
IN PLACE AT LEAST THROUGH WED/THU. MOISTURE BEGINS TO INCREASE AGAIN
BY THE END OF THE WORK WEEK ACROSS SOUTHERN PORTION OF OUR CWA. WILL
KEEP DIURNALLY DRIVEN SLIGHT TO LOW CHANCE POPS IN ACROSS THE AREA
DAYS 6 AND 7. BEGINNING TUESDAY...SHOULD SEE BELOW AVERAGE
TEMPERATURES WITH HIGHS IN THE UPPER 70S NORTH AND LOW 80S
ELSEWHERE...AND LOWS IN THE 60S. TEMPS WILL REBOUND BY THU/FRI WITH
NEAR NORMAL READINGS BY THEN.
01
&&
.CLIMATE...
RECORDS FOR 07-29
MAX TEMPERATURE MIN TEMPERATURE
STATION HIGH LOW HIGH LOW
------- ---------- ---------- ---------- ----------
KAHN 103 1952 69 1984 76 1993 60 1911
1981
KATL 103 1952 73 1984 77 1993 63 1977
1926 1986
1896
KCSG 101 1952 74 1984 78 2010 65 1994
KMCN 104 1986 74 1984 78 1986 63 1897
1952
RECORDS FOR 07-30
MAX TEMPERATURE MIN TEMPERATURE
STATION HIGH LOW HIGH LOW
------- ---------- ---------- ---------- ----------
KAHN 102 1999 69 1984 76 2010 60 1925
1915
KATL 98 1986 68 1984 78 1896 61 1936
1980
KCSG 102 2010 76 1984 79 2010 65 1957
1986
KMCN 103 1986 74 1984 76 2010 62 1920
2008
1958
RECORDS FOR 07-31
MAX TEMPERATURE MIN TEMPERATURE
STATION HIGH LOW HIGH LOW
------- ---------- ---------- ---------- ----------
KAHN 103 1999 71 1916 76 1931 59 1936
KATL 99 1999 62 1936 78 1915 59 1936
1986 1896
1980
KCSG 104 1986 74 1997 78 2011 66 1997
1981 2010
KMCN 105 1986 68 1936 77 1931 61 1936
&&
.AVIATION...
18Z UPDATE...
VFR CONDITIONS EXPECTED OVERNIGHT AT MOST OF THE TAF SITES. SOME
PATCHY MVFR FOG IS POSSIBLE AT KAHN RIGHT BEFORE SUNRISE. A COLD
FRONT WILL MOVE THROUGH THE AREA ON MONDAY. PRECIP COVERAGE IS
EXPECTED TO BE SPARSE FOR THE NORTHERN TERMINALS...WITH THE BEST
CHANCES FOR CSG AND MCN...AFTER 18Z MONDAY. WINDS WILL SHIFT TO
THE NW BEHIND THE BOUNDARY.
//ATL CONFIDENCE...18Z UPDATE...
HIGH CONFIDENCE ALL ELEMENTS.
&&
.PRELIMINARY POINT TEMPS/POPS...
ATHENS 76 91 65 86 / 20 30 10 0
ATLANTA 77 88 66 84 / 20 30 10 0
BLAIRSVILLE 68 79 58 78 / 40 30 5 10
CARTERSVILLE 74 87 63 84 / 30 30 5 0
COLUMBUS 77 92 68 88 / 10 60 20 0
GAINESVILLE 74 87 64 83 / 30 30 10 0
MACON 77 94 68 89 / 10 60 40 0
ROME 74 87 63 84 / 30 20 5 0
PEACHTREE CITY 75 89 63 85 / 20 30 10 0
VIDALIA 78 95 72 91 / 10 60 60 5
&&
.FFC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...NLISTEMAA
LONG TERM....BDL
AVIATION...NLISTEMAA
AREA FORECAST DISCUSSION
NWS PEACHTREE CITY GA
134 PM EDT SUN JUL 27 2014
.PREV DISCUSSION... /ISSUED 1012 AM EDT SUN JUL 27 2014/
UPDATE...
HIGH PRESSURE WILL CONTINUE ACROSS MUCH OF GA TODAY. ONLY SOME
CLOUDS EXPECTED...WITH VERY LITTLE CHANCE FOR ANY PRECIP UNTIL
VERY LATE IN THE AFTERNOON/EARLY EVENING ACROSS THE NORTHERN
ZONES.
HAVE ONLY MADE SOME VERY MINOR TWEAKS TO THE HOURLY GRIDS AND SKY
GRIDS. THE ISOLD POPS UP NORTH LATE STILL LOOK GOOD. ANY COMPLEX
THAT DEVELOPS ACROSS THE OHIO/TN VALLEY AND DROPS SE MAY BRUSH
EXTREME NORTHERN GA BY THE EARLY EVENING. THE HRRR CURRENTLY KEEPS
PRECIP NORTH OF THE STATE LINE...BUT WILL CONTINUE TO MONITOR.
PREV DISCUSSION... /ISSUED 737 AM EDT SUN JUL 27 2014/
SHORT TERM /TODAY THROUGH MONDAY NIGHT/...
/ISSUED AT 414 AM EDT SUN JUL 27 2014/
EXPECT A RATHER QUIET...BUT HOT WEATHER DAY TODAY AS MID AND UPPER
LEVEL RIDGING CONTINUES TO NOSE IN FROM THE WEST... RESULTING IN A
WARM/DRY WESTERLY FLOW. A FEW WEAK DISTURBANCES EMBEDDED IN THE NW
FLOW OVER THE TN VALLEY REGION WILL WARRANT A SLIGHT CHANCE OF
CONVECTION ACROSS FAR NORTH GA THIS AFTERNOON AND EVENING.
HOWEVER... THE MAIN WEATHER STORY IS A MUCH ADVERTISED COLD FRONT
THAT PUSHES INTO NORTH GA BETWEEN 5-7 AM MONDAY MORNING... ACROSS
THE ATLANTA METRO AREA BETWEEN NOON AND 2 PM MONDAY AFTERNOON...
THEN TO NEAR A COLUMBUS TO MACON LINE BETWEEN 4-6 PM MONDAY
AFTERNOON. MODELS ARE NOT SHOWING MUCH CONVECTION ALONG OR AHEAD OF
THE FRONT THROUGH MONDAY MORNING. THEN MODELS AGREE ON THE GREATER
CONVECTION FIRING ACROSS MAINLY CENTRAL GA MONDAY AFTERNOON AND
EVENING AS A STRONG DISTURBANCE INTERACTS WITH THE FRONT WHILE IT
PUSHES THROUGH A MOIST AND INCREASINGLY UNSTABLE ENVIRONMENT... WITH
EXPECTED MLCAPE VALUES IN THE 3000-4000 J/KG RANGE DURING THE HOT
MID-LATE AFTERNOON HOURS. AT THIS TIME... IT APPEARS A 40-50 KT MID
LEVEL WESTERLY FLOW WILL PRODUCE SUFFICIENT LOW LEVEL SHEAR TO
SUPPORT ISOLATED STRONG TO SEVERE STORMS ACROSS PARTS OF CENTRAL GA
MONDAY AFTERNOON AND EVENING ALONG AND AHEAD OF THE FRONT. AS A
RESULT... SPC HAS POSTED A SLIGHT RISK AREA GENERALLY ALONG AND
SOUTH OF A COLUMBUS TO MACON LINE FOR MONDAY AFTERNOON AND
EVENING... WITH THE MAIN THREATS BEING LARGE HAIL AND DAMAGING
WINDS. EXPECT THIS SEVERE POTENTIAL TO PUSH SOUTH OF THE FORECAST
AREA BY 9-10 PM MONDAY EVENING AS THE FRONT EXITS THE REGION. BEHIND
THE FRONT... EXPECT CLEARING CONDITIONS AS A COOLER/DRIER AIR MASS
SPREADS OVER THE FORECAST AREA THROUGH MONDAY NIGHT.
AS FOR TEMPS... HIGH PRESSURE INFLUENCE FROM THE WEST AND A HOT/DRY
WESTERLY FLOW WILL PUSH HIGHS TODAY WELL INTO THE 90S FOR MOST
AREAS... BUT NO RECORD HIGHS ARE EXPECTED TO BE BROKEN. THE WARM
DAYTIME TEMPS WILL HAVE TROUBLE COOLING OVERNIGHT... WITH LOWS
EXPECTED TO HOLD IN THE LOWER TO UPPER 70S FOR MOST AREAS TONIGHT.
THIS COULD RESULT IN A FEW MAX LOW TEMPS BEING BROKEN TONIGHT. WILL
HAVE TO MONITOR THIS CLOSELY. CLOUDS AND COOLER TEMPS BEHIND THE
FRONT WILL HELP HOLD HIGHS IN THE 80S ACROSS MUCH OF NORTH GA ON
MONDAY. HOWEVER... DAYTIME HIGHS ACROSS CENTRAL GA WILL BE ALLOWED
TO WARM WELL INTO THE 90S AHEAD OF THE APPROACHING COLD FRONT MONDAY
AFTERNOON.
39
LONG TERM /TUESDAY THROUGH SATURDAY/...
/ISSUED AT 414 AM EDT SUN JUL 27 2014/
THE FRONTAL BOUNDARY THAT AFFECTS THE STATE MONDAY WILL BE SOUTH OF
THE CWA BY 12Z TUE. THIS FRONTAL PASSAGE USHERS IN A AN UPPER
LEVEL DEEP LONG WAVE TROUGH WHICH REMAINS POSITIONED OVER THE AREA
THROUGH MUCH OF NEXT WEEK...KEEPING LOWER DEW POINTS AND COOLER
TEMPERATURES IN PLACE AT LEAST THROUGH WED/THU. MOISTURE BEGINS TO
INCREASE AGAIN BY THE END OF THE WORK WEEK ACROSS SOUTHERN PORTION
OF OUR CWA. WILL KEEP DIURNALLY DRIVEN SLIGHT TO LOW CHANCE POPS
IN ACROSS THE AREA DAYS 6 AND 7. BEGINNING TUESDAY...SHOULD SEE
BELOW AVERAGE TEMPERATURES WITH HIGHS IN THE UPPER 70S NORTH AND
LOW 80S ELSEWHERE...AND LOWS IN THE 60S. TEMPS WILL REBOUND BY
THU/FRI WITH NEAR NORMAL READINGS BY THEN.
01
CLIMATE...
RECORDS FOR 07-28
MAX TEMPERATURE MIN TEMPERATURE
STATION HIGH LOW HIGH LOW
------- ---------- ---------- ---------- ----------
KAHN 103 1952 75 1977 77 1936 59 1911
1926
KATL 101 1952 69 1977 77 1981 62 1911
KCSG 100 1993 81 1977 77 2010 67 1954
1952
KMCN 101 1993 76 1977 77 1958 62 1911
1952 1936
RECORDS FOR 07-29
MAX TEMPERATURE MIN TEMPERATURE
STATION HIGH LOW HIGH LOW
------- ---------- ---------- ---------- ----------
KAHN 103 1952 69 1984 76 1993 60 1911
1981
KATL 103 1952 73 1984 77 1993 63 1977
1926 1986
1896
KCSG 101 1952 74 1984 78 2010 65 1994
KMCN 104 1986 74 1984 78 1986 63 1897
1952
RECORDS FOR 07-30
MAX TEMPERATURE MIN TEMPERATURE
STATION HIGH LOW HIGH LOW
------- ---------- ---------- ---------- ----------
KAHN 102 1999 69 1984 76 2010 60 1925
1915
KATL 98 1986 68 1984 78 1896 61 1936
1980
KCSG 102 2010 76 1984 79 2010 65 1957
1986
KMCN 103 1986 74 1984 76 2010 62 1920
2008
1958
RECORDS FOR 07-31
MAX TEMPERATURE MIN TEMPERATURE
STATION HIGH LOW HIGH LOW
------- ---------- ---------- ---------- ----------
KAHN 103 1999 71 1916 76 1931 59 1936
KATL 99 1999 62 1936 78 1915 59 1936
1986 1896
1980
KCSG 104 1986 74 1997 78 2011 66 1997
1981 2010
KMCN 105 1986 68 1936 77 1931 61 1936
&&
.AVIATION...
18Z UPDATE...
VFR CONDITIONS EXPECTED OVERNIGHT AT MOST OF THE TAF SITES. SOME
PATCHY MVFR FOG IS POSSIBLE AT KAHN RIGHT BEFORE SUNRISE. A COLD
FRONT WILL MOVE THROUGH THE AREA ON MONDAY. PRECIP COVERAGE IS
EXPECTED TO BE SPARSE FOR THE NORTHERN TERMINALS...WITH THE BEST
CHANCES FOR CSG AND MCN...AFTER 18Z MONDAY. WINDS WILL SHIFT TO
THE NW BEHIND TH BOUDNARY.
//ATL CONFIDENCE...18Z UPDATE...
HIGH CONFIDENCE ALL ELEMENTS.
&&
.PRELIMINARY POINT TEMPS/POPS...
ATHENS 96 74 92 66 / 10 20 30 10
ATLANTA 93 76 90 67 / 10 20 30 10
BLAIRSVILLE 88 68 82 58 / 20 40 30 5
CARTERSVILLE 93 73 89 64 / 10 30 30 5
COLUMBUS 96 77 94 69 / 5 10 60 20
GAINESVILLE 92 74 88 66 / 10 30 30 10
MACON 96 75 95 67 / 5 10 60 40
ROME 93 73 89 65 / 10 30 20 5
PEACHTREE CITY 93 72 91 65 / 10 20 30 10
VIDALIA 97 78 96 72 / 5 10 60 60
&&
.FFC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
210 PM CDT SUN JUL 27 2014
.DISCUSSION...
1142 AM CDT
HAVE UPDATED FORECAST TO FOCUS SHOWER/THUNDERSTORM POTENTIAL ACROSS
FAR EASTERN CWA ALONG/AHEAD OF COLD FRONT MIDDAY/EARLY AFTERNOON...
WITH SCATTERED SHOWERS AND ISOLATED THUNDERSTORMS THEN DEVELOPING
THIS AFTERNOON WITH GREATEST COVERAGE NORTH...LESS SOUTH. MADE SOME
ADJUSTMENTS TO TEMPS AS WELL...WITH WARMER HIGHS EAST/SOUTHEAST
SETTLING BACK INTO THE MID-UPPER 70S BEHIND COLD FRONT LATER TODAY.
COLD FRONT WAS APPROACHING A CHICAGO-PONTIAC ILLINOIS LINE AT 16Z...
AND WILL CONTINUE TO PUSH EAST ACROSS NORTHWEST INDIANA AND EAST
CENTRAL ILLINOIS INTO EARLY AFTERNOON. HIGH-RES GUIDANCE HAS
CONTINUED TO DEPICT CONVECTIVE DEVELOPMENT ALONG/AHEAD OF THE FRONT
IN THE NEXT 1-2 HOURS...THOUGH WEST-SOUTHWEST WINDS AHEAD OF THE
BOUNDARY ARE RESULTING IN GENERALLY WEAK CONVERGENCE. WITH TEMPS
RISING INTO THE LOW-MID 80S AND SURFACE DEW POINT TEMPS IN THE
LOW-MID 70S AHEAD OF THE FRONT...FORECAST SOUNDINGS DO INDICATE
1000+ J/KG OF MLCAPE ALTHOUGH TREND TOWARD LATER INITIATION AND LESS
COVERAGE NOTED IN HIGH-RES MODELS. HAVE ADJUSTED SPATIAL COVERAGE OF
POPS TO FAVOR FAR EASTERN AREAS NEXT FEW HOURS AHEAD OF THE FRONT.
NOTE THAT SPC HAS REMOVED EASTERN CWA FROM SLGT RISK WITH THE
UPDATED DAY 1 OUTLOOK. IF DEEP UPDRAFTS ARE ABLE TO DEVELOP AHEAD OF
THE FRONT STILL LOOKS TO BE POTENTIAL FOR GUSTY WINDS/SMALL HAIL...
THOUGH NO ORGANIZED SEVERE THREAT MAINLY DUE TO UNFAVORABLE LOW
LEVEL CONVERGENCE.
OTHERWISE...STRONG/COMPACT UPPER LOW DIGGING SOUTHEAST ACROSS THE
WESTERN GREAT LAKES REGION THIS AFTERNOON PER WATER VAPOR IMAGERY.
RESULTING HEIGHT FALLS/COOLING ALOFT IS EXPECTED TO PRODUCE
SCATTERED SHOWERS AND ISOLATED THUNDERSTORMS ACROSS ESPECIALLY
NORTHERN PARTS OF THE CWA LATER THIS AFTERNOON...WITH REGIONAL RADAR
MOSAIC ALREADY SHOWING THIS TREND ACROSS WI. INSTABILITY APPEARS TO
WEAKEN WITH TIME WITH COOL/DRY LOW LEVEL ADVECTION...SUGGESTING
LOWER COVERAGE OF THUNDER BY LATE AFTERNOON.
TEMP WISE...SOME MID-80S NOTED ALREADY ACROSS NORTHEAST IL AHEAD OF
FRONT. HAVE BUMPED MAX TEMPS A LITTLE ACROSS THE AREA AND ESPECIALLY
EAST/SOUTHEAST...WITH SOME COOLING EXPECTED BACK INTO THE UPPER 70S
OR SO THROUGH THE AFTERNOON WITH COOLER AIR ALOFT AND INCREASED
CLOUD COVER.
RATZER
//PREV DISCUSSION...
322 AM CDT
SYNOPSIS...ONE MORE DAY OF A DIFFICULT AND MESSY PATTERN THAT WILL
RESULT IN SHOWERS AND THUNDERSTORMS ACROSS THE REGION. NO SEVERE
STORMS ARE EXPECTED. TEMPERATURES FALL THIS AFTERNOON AND REMAIN
BELOW NORMAL THROUGH THE REST OF THE WEEK. WE DRY OUT MONDAY AND
THEN HAVE LOW CHANCES OF PRECIP TUESDAY THROUGH SATURDAY.
TODAY AND TONIGHT...
AN UPPER LEVEL LOW IS OVER NORTHERN MINNESOTA WHILE A LARGER LOW IS
OVER NORTHERN QUEBEC. A SHORTWAVE TROUGH IS ALSO OVER EASTERN IOWA
WITH CONVECTION OVER CENTRAL WI. SPOTTY SHOWERS/SPRINKLES HAVE
SPROUTED OVER SOUTHEAST WI AND NOT EXPECTING MUCH ACTIVITY FROM
THOSE SPRINKLES. ADDITIONAL MORE IMPRESSIVE CONVECTION HAS FIRED
ALONG A WEAK BOUNDARY OVER CENTRAL IL. MAY SEE A FEW STORMS SOUTH OF
A PERU TO RENSSELAER LINE EARLY THIS MORNING.
FOG IS PRESENT OVER MUCH OF THE FORECAST AREA THIS MORNING AS
WELL. CLOUD COVER IS EXPANDING FROM SOUTH TO NORTH AND VSBY
INCREASES AS THE CLOUDS MOVE OVERHEAD. AS SUCH WILL HOLD OFF ON A
DENSE FOG ADVISORY FOR NOW AND SEE HOW THE CLOUD COVER SPREADS
ACROSS THE REGION.
EXPECTING ADDITIONAL CONVECTION TO FIRE AHEAD OF THE SHORTWAVE THIS
MORNING AND MOVE INTO NORTH CENTRAL IL. INSTABILITY MAY BE
LIMITED...BUT SOME THUNDER SHOULD BE REALIZED BASED ON
OBSERVATIONAL TRENDS UPSTREAM. THE SHOWERS AND STORMS WILL PUSH
EAST INTO THE AFTERNOON AS THE SHORTWAVE MOVES THROUGH. A COLD
FRONT CURRENTLY ACROSS NW WI THROUGH CENTRAL IA WILL ALSO
TRANSVERSE THE REGION AHEAD OF THE UPPER LEVEL LOW. THE LOW WILL
SWING OVER THE LAKE THIS AFTERNOON AND EXPECTING ADDITIONAL
ISOLATED TO SCATTERED STORMS WITH THIS FEATURE. TODAY WILL NOT BE
A WASH OUT HOWEVER AND THERE SHOULD BE PLENTY OF DRY HOURS.
ISOLATED SHOWERS CONTINUE INTO THE EVENING AND THEN THE BACK SIDE
OF THE UPPER LEVEL TROUGH SLIDES SOUTH THROUGH THE REGION
OVERNIGHT CLEARING OUT THE CLOUDS.
GUSTY WINDS ARE EXPECTED...AT TIMES TO 30 MPH THIS AFTERNOON.
WITH THE STRONG WINDS OVER LAKE MICHIGAN ORIENTED PARALLEL TO THE
FETCH...WAVES WILL BUILD CONSIDERABLY TONIGHT AND PERSIST INTO
MONDAY...AND A BEACH HAZARDS STATEMENT WILL GO INTO EFFECT FOR ALL
LAKE ADJACENT COUNTIES IN THE FORECAST AREA.
CLOUD COVER SHOULD STAY WITH US MOST OF THE DAY LIMITING HOW WARM WE
GET AGAIN. HIGHS WILL VARY FROM AROUND 80 NORTH TO THE MID 80S
SOUTH WHERE THERE COULD BE MORE SUNSHINE. TEMPS AND DEWPOINTS WILL
FALL THIS AFTERNOON THOUGH AS COOLER AIR MOVES IN BEHIND THE COLD
FRONT.
MONDAY...
THE UPPER LEVEL LOW WEAKENS TO AN OPEN TROUGH AND THEN MERGES WITH
THE STRONGER LOW OVER QUEBEC MONDAY NIGHT. WE STAY STUCK IN AN
UPPER LEVEL PATTERN WITH A RIDGE TO THE WEST AND TROUGH TO THE
EAST. THE SURFACE LOW MOVES OVER NEW ENGLAND MONDAY MORNING AND
HIGH PRESSURE BUILDS OVER THE PLAINS. MONDAY LOOKS DRY WITH WEAK
VORTICITY STREAMERS PASSING BY OVERHEAD. HIGHS WILL BE WELL BELOW
NORMAL IN THE LOW TO MID 70S. ONSHORE FLOW WILL KEEP THE LAKEFRONT
NEAR 70. THEN A BEAUTIFUL NIGHT FOR SLEEPING IS IN STORE WITH LOWS
IN THE MID 50S...EXCEPT FOR AROUND 60 DOWNTOWN.
TUESDAY THROUGH SATURDAY...
WE REMAIN IN THE STAGNANT UPPER LEVEL PATTERN WITH A SURFACE HIGH
OVER THE PLAINS. KEPT PERIODIC LOW CHANCES OF SHOWERS AND STORMS IN
THE EXTENDED FORECAST AS VORTICITY STREAMERS CONTINUE TO ROTATE
THROUGH THE REGION. MOISTURE IS NOT PLENTIFUL SO NOT EXPECTING MUCH
PRECIP AT THIS TIME. TEMPERATURES ALSO REMAIN BELOW NORMAL IN THE
70S WITH A FEW SITES MAYBE REACHING 80.
JEE
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 18Z...
* STRONG/GUSTY WEST/NORTHWEST WINDS THRU EARLY EVENING.
* CHANCE OF SHRA MID AFTERNOON THRU THIS EVENING.
* WIND SHIFT TO NORTH/NORTHEAST MID/LATE EVENING.
* CHANCE OF MVFR CIGS LATE EVENING/OVERNIGHT.
* GUSTY NORTH/NORTHEAST WINDS MONDAY. CMS
//DISCUSSION...UPDATED 18Z...
FRONTAL BOUNDARY JUST EAST OF ORD/MDW WITH A FEW CELLS DEVELOPING
OVER THE LAKE AND ADDITIONAL DEVELOPMENT SHOULD REMAIN EAST OF
ORD/MDW BUT MAY STILL IMPACT GYY THROUGH 19Z OR SO UNTIL THE FRONT
PUSHES EAST OF THERE. AS COOLER AIR ALOFT SPREADS ACROSS THE AREA
THIS AFTERNOON...THERE COULD BE SOME INSTABILITY SHOWERS...
PERHAPS ISOLATED THUNDER...FROM MID AFTERNOON THROUGH EARLY
EVENING.
WEST/NORTHWEST WINDS HAVE INCREASED INTO THE 15-20KT RANGE WITH
GUSTS INTO THE MID 20KT RANGE. WITH COOLER AND DRIER AIR ADVECTING
INTO THE REGION...LOW LEVEL MIXING WILL BE FAIRLY EFFICIENT
BRINGING STRONGER WINDS TO THE SURFACE AND BUMPED SPEEDS/GUSTS UP
JUST A BIT WITH GUSTS INTO THE UPPER 20KT RANGE POSSIBLE FOR MUCH
OF THE AFTERNOON/EARLY EVENING.
ANOTHER COLD FRONT/WIND SHIFT IS EXPECTED THIS EVENING WHICH WILL
LIKELY SHIFT WINDS TO THE NORTH/NORTHEAST. CHANGES TO TIMING MAY
BE NEEDED WITH FUTURE UPDATES BUT CONFIDENCE FOR A SHIFT TO THE
NORTH/NORTHEAST IS INCREASING. IN ADDITION...THERE COULD BE A
PERIOD OF MVFR CIGS BEHIND THIS FRONT. WINDS WILL TEND TO SHIFT
BACK NORTH/NORTHWEST OVERNIGHT...THEN SHIFT BACK NORTH/NORTHEAST
MONDAY MORNING AND REMAIN GUSTY FOR MUCH OF MONDAY. CMS
//ORD AND MDW CONFIDENCE...UPDATED 18Z...
* HIGH FOR WINDS THIS AFTERNOON...MEDIUM FOR THE REST OF THE PERIOD.
* LOW FOR SHRA THIS AFTERNOON/EARLY EVENING.
* MEDIUM FOR MVFR CIGS LATE EVENING/OVERNIGHT. CMS
//OUTLOOK FOR ORD/MDW FOR 00Z TUESDAY-12Z SUNDAY...UPDATED 12Z...
MONDAY NIGHT...VFR.
TUESDAY...SLIGHT CHANCE OF AFTERNOON TSRA.
WEDNESDAY...SLIGHT CHANCE OF TSRA.
THURSDAY-SATURDAY...SLIGHT CHANCES OF TSRA. NORTHEAST WINDS.
MTF
&&
.MARINE...
210 PM CDT
AN ACTIVE PERIOD OF WEATHER IN UNDERWAY OVER LAKE MICHIGAN.
DEEPENING LOW PRESSURE HAS PASSED ACROSS NORTHERN LAKE MICHIGAN
AND IS MOVING THROUGH LOWER MICHIGAN THIS AFTERNOON TO THE EASTERN
GREAT LAKES THIS EVENING. FOLLOWING THE PASSAGE OF THIS LOW AND AN
ASSOCIATED COLD FRONT...STRENGTHENING NORTHWEST WINDS ARE
FILTERING ACROSS THE LAKE AND QUICKLY INCREASING TO 20-25KT WITH
OCNL GUSTS TO 30KT AND SCATTERED THUNDERSTORMS. THE SCATTERED
THUNDERSTORMS SHOULD CONTINUE INTO THE EVENING WHILE WINDS
GRADUALLY VEER MORE NORTHERLY AND INCREASE TO PREVAILING 30KT.
OCNL GALE FORCE GUSTS TO 35 KT ARE POSSIBLE...BUT SHOULD NOT BE
PERSISTENT ENOUGH TO NECESSITATE A GALE WARNING. SMALL CRAFT
ADVISORIES HAVE ALREADY BEEN HOISTED FOR THE ILLINOIS AND INDIANA
NEARSHORE WATERS AND NO CHANGE HAS BEEN MADE TO THE TIMING
DETAILS. HIGH PRESSURE BUILDING ACROSS THE NORTHERN PLAINS THIS
AFTERNOON AND SHOULD BEGIN TO SPREAD ACROSS THE WESTERN GREAT
LAKES MONDAY. AS THE HIGH SPREADS ACROSS THE LAKE LATE
MONDAY...WINDS SHOULD DIMINISH QUICKLY. ON TUESDAY...A SFC TROUGH
OR OR WEAK COLD FRONT TRACKING SOUTH DOWN THE LAKE WILL BRING A
REINFORCING SHOT OF COOLER AIR...BRINGING A BRIEF INCREASE TO NWLY
WINDS TUESDAY MORNING. FOLLOWING THE PASSAGE OF THIS WEAK
TROUGH/COLD FRONT...THE HIGH PRESSURE WILL SPREAD ACROSS THE
WESTERN GREAT LAKES TO THE OHIO VALLEY BY WEDNESDAY. HIGH PRESSURE
WILL BE THE DOMINANT FEATURE OVER THE GREAT LAKES REGION FROM MID
WEEK INTO THE WEEKEND...SETTING UP A PERIOD OF QUIET WEATHER WITH
LIGHT AND VARIABLE WINDS AND MINIMAL WAVE ACTION.
KREIN
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...BEACH HAZARDS STATEMENT...ILZ014...10 PM SUNDAY TO 4 AM TUESDAY.
BEACH HAZARDS STATEMENT...ILZ006...10 PM SUNDAY TO 10 PM MONDAY.
IN...BEACH HAZARDS STATEMENT...INZ001-INZ002...6 PM SUNDAY TO 4 AM
TUESDAY.
LM...SMALL CRAFT ADVISORY...NEARSHORE WINTHROP HARBOR TO NORTHERLY IS UNTIL 10 PM MONDAY.
SMALL CRAFT ADVISORY...LMZ742-LMZ743 UNTIL 4 AM TUESDAY.
SMALL CRAFT ADVISORY...NEARSHORE GARY TO MICHIGAN CITY IN UNTIL 4 AM TUESDAY.
&&
$$
VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
WWW.FACEBOOK.COM/US.NATIONALWEATHERSERVICE.CHICAGO.GOV
WWW.TWITTER.COM/NWSCHICAGO
WWW.YOUTUBE.COM/NWSCHICAGO
[top]
Area Forecast Discussion
National Weather Service Lincoln IL
206 PM CDT Sun Jul 27 2014
.DISCUSSION...
ISSUED 200 PM CDT Sun Jul 27 2014
18z Surface map indicating cold front has shifted into extreme
southern Illinois with a secondary boundary/dew point dicontinuity
located from near Chicago southwest to Bloomington to just south
of Quincy. Early afternoon temps have risen into the mid to upper
80s with dew points still in the 70s to the east of the secondary
boundary, with upper 50s to lower 60 dew points filtering southeast
into west central IL. Along and just to the east of this dew point
discontinuity, widely scattered showers and thunderstorms have
developed. Local objective analysis indicates Mixed Layer Capes of
1500-2000 J/Kg to the east of boundary with minimal low level
convergence noted at 18z. 0-6km bulk shear values in the 50-60 kt
range, so any strong updraft along the boundary will have the
capability of producing gusty winds. Visible satellite data showing
quite a bit of wrap around moisture shifting south into the lower
Great Lakes early this afternoon as an upper level trof shifts
southeast.
SHORT TERM...Tonight through Wednesday
Main forecast challenge this period will be with temperatures and
amount of cloud cover and possible showers associated with the
aforementioned Great Lakes trof as it slowly settles south into
the upper Midwest early this week. Models in decent agreement with
respect to the trof deepening in over the Great Lakes this week.
As the cooler temps aloft and high based cu field settle south,
we may see some shower activity across the northeast into early
this evening but several of the hi-res models suggest the bulk of
the shower threat should be east of our area by early this eve so
at this point will keep the evening portion of the forecast dry.
Forecast soundings have suggested the potential for some ground fog
development by morning but with as much mixing that is occurring
this afternoon, will hold off mentioning for now. The southeast may
be close as they will be last to really mix out later this afternoon,
but even there will keep it out of the forecast.
Rather quiet weather expected over the remainder of the forecast period
with the upper trof settling south over the next several days. As temps
aloft continue to cool, our chances for some diurnally driven showers
and storms will increase, especially as we head towards midweek and
beyond. Latest NAM-WRF model indicates parts of our area may see some
afternoon showers tomorrow afternoon. Think that model may be too
strong aloft with the trof and associated cold pool so will tend to
side more with the GFS solution in keeping the area dry for tomorrow.
Temperatures will be cooler than normal but on the pleasant side with
afternoon temps in the mid to upper 70s tomorrow and Tuesday and around
80 by Wednesday with early morning lows in the mid 50s to near 60.
LONG TERM...Thursday through Sunday
Low ensemble spread with the trof expected to drop south into the
Ohio Valley by the weekend. The real challenge will be how the
medium range models handle the individual shortwaves rotating thru
the trof and combining with daytime heating and cool temperatures
aloft to bring about daily chances for mainly afternoon and evening
showers during this period. 850 temp progs suggest not a great deal
of temperature change during this period. We should edge back to
or just above 80 for daytime highs with early morning lows around
60 degrees.
Smith
&&
.AVIATION...
ISSUED 1255 PM CDT Sun Jul 27 2014
One cold front has passed southeast of IL by early afternoon with
scattered strong to severe thunderstorms ahead of it over OH and
eastern KY. Meanwhile another frontal boundary delineated by
enhanced narrow band of cumulus clouds extended from the south side
of Chicago through BMI airport to Jacksonville. Tropical/muggy
dewpoints in lower to middle 70s se of this boundary, while dewpoints
fall through the 60s and even some upper 50s over IL river valley.
Isolated convection recently developed along and just ahead of
this boundary southeast of BMI. Will carry VCSH at southeast airports
of DEC and CMI next few hours until this boundary passes se of
them during mid afternoon. Have scattered cumulus clouds 2.5-5k ft
this afternoon and broken at times from I-55 se next few hours
with high end MVFR ceilings possible. Broken cumulus cloud field
over WI/MN and central/ne IA could skirt northern taf sites of PIA
and BMI later this afternoon and early evening. Breezy WNW winds
12-17 kts with gusts 18-25 kts this afternoon and early evening to
diminish to 7-10 kts after sunset. Drier air advecting into
central IL should limit fog development overnight to patchy
shallow ground fog near rivers/streams especially in southeast IL,
so kept out of TAFS. Expect NNW winds 9-14 kts by 15Z/10 am Monday
with few gusts near 20 kts by midday Monday as scattered cumulus
clouds around 4k ft redevelop.
07
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
Area Forecast Discussion
National Weather Service Lincoln IL
206 PM CDT Sun Jul 27 2014
.DISCUSSION...
ISSUED 200 PM CDT Sun Jul 27 2014
18z Surface map indicating cold front has shifted into extreme
southern Illinois with a secondary boundary/dew point dicontinuity
located from near Chicago southwest to Bloomington to just south
of Quincy. Early afternoon temps have risen into the mid to upper
80s with dew points still in the 70s to the east of the secondary
boundary, with upper 50s to lower 60 dew points filtering southeast
into west central IL. Along and just to the east of this dew point
discontinuity, widely scattered showers and thunderstorms have
developed. Local objective analysis indicates Mixed Layer Capes of
1500-2000 J/Kg to the east of boundary with minimal low level
convergence noted at 18z. 0-6km bulk shear values in the 50-60 kt
range, so any strong updraft along the boundary will have the
capability of producing gusty winds. Visible satellite data showing
quite a bit of wrap around moisture shifting south into the lower
Great Lakes early this afternoon as an upper level trof shifts
southeast.
SHORT TERM...Tonight through Wednesday
Main forecast challenge this period will be with temperatures and
amount of cloud cover and possible showers associated with the
aforementioned Great Lakes trof as it slowly settles south into
the upper Midwest early this week. Models in decent agreement with
respect to the trof deepening in over the Great Lakes this week.
As the cooler temps aloft and high based cu field settle south,
we may see some shower activity across the northeast into early
this evening but several of the hi-res models suggest the bulk of
the shower threat should be east of our area by early this eve so
at this point will keep the evening portion of the forecast dry.
Forecast soundings have suggested the potential for some ground fog
development by morning but with as much mixing that is occurring
this afternoon, will hold off mentioning for now. The southeast may
be close as they will be last to really mix out later this afternoon,
but even there will keep it out of the forecast.
Rather quiet weather expected over the remainder of the forecast period
with the upper trof settling south over the next several days. As temps
aloft continue to cool, our chances for some diurnally driven showers
and storms will increase, especially as we head towards midweek and
beyond. Latest NAM-WRF model indicates parts of our area may see some
afternoon showers tomorrow afternoon. Think that model may be too
strong aloft with the trof and associated cold pool so will tend to
side more with the GFS solution in keeping the area dry for tomorrow.
Temperatures will be cooler than normal but on the pleasant side with
afternoon temps in the mid to upper 70s tomorrow and Tuesday and around
80 by Wednesday with early morning lows in the mid 50s to near 60.
LONG TERM...Thursday through Sunday
Low ensemble spread with the trof expected to drop south into the
Ohio Valley by the weekend. The real challenge will be how the
medium range models handle the individual shortwaves rotating thru
the trof and combining with daytime heating and cool temperatures
aloft to bring about daily chances for mainly afternoon and evening
showers during this period. 850 temp progs suggest not a great deal
of temperature change during this period. We should edge back to
or just above 80 for daytime highs with early morning lows around
60 degrees.
Smith
&&
.AVIATION...
ISSUED 1255 PM CDT Sun Jul 27 2014
One cold front has passed southeast of IL by early afternoon with
scattered strong to severe thunderstorms ahead of it over OH and
eastern KY. Meanwhile another frontal boundary delineated by
enhanced narrow band of cumulus clouds extended from the south side
of Chicago through BMI airport to Jacksonville. Tropical/muggy
dewpoints in lower to middle 70s se of this boundary, while dewpoints
fall through the 60s and even some upper 50s over IL river valley.
Isolated convection recently developed along and just ahead of
this boundary southeast of BMI. Will carry VCSH at southeast airports
of DEC and CMI next few hours until this boundary passes se of
them during mid afternoon. Have scattered cumulus clouds 2.5-5k ft
this afternoon and broken at times from I-55 se next few hours
with high end MVFR ceilings possible. Broken cumulus cloud field
over WI/MN and central/ne IA could skirt northern taf sites of PIA
and BMI later this afternoon and early evening. Breezy WNW winds
12-17 kts with gusts 18-25 kts this afternoon and early evening to
diminish to 7-10 kts after sunset. Drier air advecting into
central IL should limit fog development overnight to patchy
shallow ground fog near rivers/streams especially in southeast IL,
so kept out of TAFS. Expect NNW winds 9-14 kts by 15Z/10 am Monday
with few gusts near 20 kts by midday Monday as scattered cumulus
clouds around 4k ft redevelop.
07
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
Area Forecast Discussion
National Weather Service Lincoln IL
206 PM CDT Sun Jul 27 2014
.DISCUSSION...
ISSUED 200 PM CDT Sun Jul 27 2014
18z Surface map indicating cold front has shifted into extreme
southern Illinois with a secondary boundary/dew point dicontinuity
located from near Chicago southwest to Bloomington to just south
of Quincy. Early afternoon temps have risen into the mid to upper
80s with dew points still in the 70s to the east of the secondary
boundary, with upper 50s to lower 60 dew points filtering southeast
into west central IL. Along and just to the east of this dew point
discontinuity, widely scattered showers and thunderstorms have
developed. Local objective analysis indicates Mixed Layer Capes of
1500-2000 J/Kg to the east of boundary with minimal low level
convergence noted at 18z. 0-6km bulk shear values in the 50-60 kt
range, so any strong updraft along the boundary will have the
capability of producing gusty winds. Visible satellite data showing
quite a bit of wrap around moisture shifting south into the lower
Great Lakes early this afternoon as an upper level trof shifts
southeast.
SHORT TERM...Tonight through Wednesday
Main forecast challenge this period will be with temperatures and
amount of cloud cover and possible showers associated with the
aforementioned Great Lakes trof as it slowly settles south into
the upper Midwest early this week. Models in decent agreement with
respect to the trof deepening in over the Great Lakes this week.
As the cooler temps aloft and high based cu field settle south,
we may see some shower activity across the northeast into early
this evening but several of the hi-res models suggest the bulk of
the shower threat should be east of our area by early this eve so
at this point will keep the evening portion of the forecast dry.
Forecast soundings have suggested the potential for some ground fog
development by morning but with as much mixing that is occurring
this afternoon, will hold off mentioning for now. The southeast may
be close as they will be last to really mix out later this afternoon,
but even there will keep it out of the forecast.
Rather quiet weather expected over the remainder of the forecast period
with the upper trof settling south over the next several days. As temps
aloft continue to cool, our chances for some diurnally driven showers
and storms will increase, especially as we head towards midweek and
beyond. Latest NAM-WRF model indicates parts of our area may see some
afternoon showers tomorrow afternoon. Think that model may be too
strong aloft with the trof and associated cold pool so will tend to
side more with the GFS solution in keeping the area dry for tomorrow.
Temperatures will be cooler than normal but on the pleasant side with
afternoon temps in the mid to upper 70s tomorrow and Tuesday and around
80 by Wednesday with early morning lows in the mid 50s to near 60.
LONG TERM...Thursday through Sunday
Low ensemble spread with the trof expected to drop south into the
Ohio Valley by the weekend. The real challenge will be how the
medium range models handle the individual shortwaves rotating thru
the trof and combining with daytime heating and cool temperatures
aloft to bring about daily chances for mainly afternoon and evening
showers during this period. 850 temp progs suggest not a great deal
of temperature change during this period. We should edge back to
or just above 80 for daytime highs with early morning lows around
60 degrees.
Smith
&&
.AVIATION...
ISSUED 1255 PM CDT Sun Jul 27 2014
One cold front has passed southeast of IL by early afternoon with
scattered strong to severe thunderstorms ahead of it over OH and
eastern KY. Meanwhile another frontal boundary delineated by
enhanced narrow band of cumulus clouds extended from the south side
of Chicago through BMI airport to Jacksonville. Tropical/muggy
dewpoints in lower to middle 70s se of this boundary, while dewpoints
fall through the 60s and even some upper 50s over IL river valley.
Isolated convection recently developed along and just ahead of
this boundary southeast of BMI. Will carry VCSH at southeast airports
of DEC and CMI next few hours until this boundary passes se of
them during mid afternoon. Have scattered cumulus clouds 2.5-5k ft
this afternoon and broken at times from I-55 se next few hours
with high end MVFR ceilings possible. Broken cumulus cloud field
over WI/MN and central/ne IA could skirt northern taf sites of PIA
and BMI later this afternoon and early evening. Breezy WNW winds
12-17 kts with gusts 18-25 kts this afternoon and early evening to
diminish to 7-10 kts after sunset. Drier air advecting into
central IL should limit fog development overnight to patchy
shallow ground fog near rivers/streams especially in southeast IL,
so kept out of TAFS. Expect NNW winds 9-14 kts by 15Z/10 am Monday
with few gusts near 20 kts by midday Monday as scattered cumulus
clouds around 4k ft redevelop.
07
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
Area Forecast Discussion
National Weather Service Lincoln IL
206 PM CDT Sun Jul 27 2014
.DISCUSSION...
ISSUED 200 PM CDT Sun Jul 27 2014
18z Surface map indicating cold front has shifted into extreme
southern Illinois with a secondary boundary/dew point dicontinuity
located from near Chicago southwest to Bloomington to just south
of Quincy. Early afternoon temps have risen into the mid to upper
80s with dew points still in the 70s to the east of the secondary
boundary, with upper 50s to lower 60 dew points filtering southeast
into west central IL. Along and just to the east of this dew point
discontinuity, widely scattered showers and thunderstorms have
developed. Local objective analysis indicates Mixed Layer Capes of
1500-2000 J/Kg to the east of boundary with minimal low level
convergence noted at 18z. 0-6km bulk shear values in the 50-60 kt
range, so any strong updraft along the boundary will have the
capability of producing gusty winds. Visible satellite data showing
quite a bit of wrap around moisture shifting south into the lower
Great Lakes early this afternoon as an upper level trof shifts
southeast.
SHORT TERM...Tonight through Wednesday
Main forecast challenge this period will be with temperatures and
amount of cloud cover and possible showers associated with the
aforementioned Great Lakes trof as it slowly settles south into
the upper Midwest early this week. Models in decent agreement with
respect to the trof deepening in over the Great Lakes this week.
As the cooler temps aloft and high based cu field settle south,
we may see some shower activity across the northeast into early
this evening but several of the hi-res models suggest the bulk of
the shower threat should be east of our area by early this eve so
at this point will keep the evening portion of the forecast dry.
Forecast soundings have suggested the potential for some ground fog
development by morning but with as much mixing that is occurring
this afternoon, will hold off mentioning for now. The southeast may
be close as they will be last to really mix out later this afternoon,
but even there will keep it out of the forecast.
Rather quiet weather expected over the remainder of the forecast period
with the upper trof settling south over the next several days. As temps
aloft continue to cool, our chances for some diurnally driven showers
and storms will increase, especially as we head towards midweek and
beyond. Latest NAM-WRF model indicates parts of our area may see some
afternoon showers tomorrow afternoon. Think that model may be too
strong aloft with the trof and associated cold pool so will tend to
side more with the GFS solution in keeping the area dry for tomorrow.
Temperatures will be cooler than normal but on the pleasant side with
afternoon temps in the mid to upper 70s tomorrow and Tuesday and around
80 by Wednesday with early morning lows in the mid 50s to near 60.
LONG TERM...Thursday through Sunday
Low ensemble spread with the trof expected to drop south into the
Ohio Valley by the weekend. The real challenge will be how the
medium range models handle the individual shortwaves rotating thru
the trof and combining with daytime heating and cool temperatures
aloft to bring about daily chances for mainly afternoon and evening
showers during this period. 850 temp progs suggest not a great deal
of temperature change during this period. We should edge back to
or just above 80 for daytime highs with early morning lows around
60 degrees.
Smith
&&
.AVIATION...
ISSUED 1255 PM CDT Sun Jul 27 2014
One cold front has passed southeast of IL by early afternoon with
scattered strong to severe thunderstorms ahead of it over OH and
eastern KY. Meanwhile another frontal boundary delineated by
enhanced narrow band of cumulus clouds extended from the south side
of Chicago through BMI airport to Jacksonville. Tropical/muggy
dewpoints in lower to middle 70s se of this boundary, while dewpoints
fall through the 60s and even some upper 50s over IL river valley.
Isolated convection recently developed along and just ahead of
this boundary southeast of BMI. Will carry VCSH at southeast airports
of DEC and CMI next few hours until this boundary passes se of
them during mid afternoon. Have scattered cumulus clouds 2.5-5k ft
this afternoon and broken at times from I-55 se next few hours
with high end MVFR ceilings possible. Broken cumulus cloud field
over WI/MN and central/ne IA could skirt northern taf sites of PIA
and BMI later this afternoon and early evening. Breezy WNW winds
12-17 kts with gusts 18-25 kts this afternoon and early evening to
diminish to 7-10 kts after sunset. Drier air advecting into
central IL should limit fog development overnight to patchy
shallow ground fog near rivers/streams especially in southeast IL,
so kept out of TAFS. Expect NNW winds 9-14 kts by 15Z/10 am Monday
with few gusts near 20 kts by midday Monday as scattered cumulus
clouds around 4k ft redevelop.
07
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
Area Forecast Discussion
National Weather Service Lincoln IL
1258 PM CDT Sun Jul 27 2014
.DISCUSSION...
ISSUED 1045 AM CDT Sun Jul 27 2014
Forecast generally looks on track today and main adjustment is
low cloud cover lingering longer than earlier expected se of I-55.
Skies should still become partly to mostly sunny across central
and evenually eastern IL during the afternoon. Will continue
small chances of showers and thunderstorms over eastern IL mainly
east of I-57 this afternoon. SPC has slight risk of severe storms
from the IL/IN border east across IN/KY/OH with moderate risk over
in the foothills of the Appalachians in eastern KY and southern OH.
Cold front was pushing se into far southeast IL near the Wabash
River late this morning with WNW winds increasing behind the front
over central IL and gusting 15-25 mph over IL river valley. Still
muggy dewpoints in the low to mid 70s se of IL river and upper 60s
nw of IL river. Dewpoints drop off into the upper 50s and lower
60s upstream near the IA/IL border and should advect se into
central IL during the afternoon. Southeast IL will still be muggy
today where dewpoints currently in mid 70s but should slip into
the mid to upper 60s during the afternoon. Highs in the low to mid
80s look on track today with return of more sunshine with some
upper 80s near Lawrenceville.
07
&&
.AVIATION...
ISSUED 1255 PM CDT Sun Jul 27 2014
One cold front has passed southeast of IL by early afternoon with
scattered strong to severe thunderstorms ahead of it over OH and
eastern KY. Meanwhile another frontal boundary delineated by
enhanced narrow band of cumulus clouds extended from the south side
of Chicago through BMI airport to Jacksonville. Tropical/muggy
dewpoints in lower to middle 70s se of this boundary, while dewpoints
fall through the 60s and even some upper 50s over IL river valley.
Isolated convection recently developed along and just ahead of
this boundary southeast of BMI. Will carry VCSH at southeast airports
of DEC and CMI next few hours until this boundary passes se of
them during mid afternoon. Have scattered cumulus clouds 2.5-5k ft
this afternoon and broken at times from I-55 se next few hours
with high end MVFR ceilings possible. Broken cumulus cloud field
over WI/MN and central/ne IA could skirt northern taf sites of PIA
and BMI later this afternoon and early evening. Breezy WNW winds
12-17 kts with gusts 18-25 kts this afternoon and early evening to
diminish to 7-10 kts after sunset. Drier air advecting into
central IL should limit fog development overnight to patchy
shallow ground fog near rivers/streams especially in southeast IL,
so kept out of TAFS. Expect NNW winds 9-14 kts by 15Z/10 am Monday
with few gusts near 20 kts by midday Monday as scattered cumulus
clouds around 4k ft redevelop.
07
&&
.PREV DISCUSSION...
ISSUED 245 AM CDT Sun Jul 27 2014
Surface map a mess in the wake of yesterday evenings convection.
Broad surface trof/frontal boundary hung up over the region with light
and variable winds. Some patchy fog out there, with only a couple
sites dropping to a mile visibility this morning. Some convection
blowing up over the area turning over some of the air and helping
to block much more of a vis drop in that area...and potentially
limiting the temp drop predawn. Even high res short term models
not handling the current conditions well, much less the next 12
hours. Many mesoscale dynamics out there not being represented.
Front still not yet through the region...and first issue with the
forecast will be hanging on to pops, particularly in the east with
the frontal passage later mid day and this afternoon.
SHORT TERM...Today through Monday night...
Keeping chances in for scattered showers and thunderstorms until
the front can progress through the area. Though today is expected
to get warm in front of the boundary...tomorrow is expected to see
significantly cooler temps with some relatively drier air
filtering in. Precipitation chances drop out of the forecast for
tonight and tomorrow. But it bears mentioning that todays pops
will be complicated by small perturbations that are not being
resolved well in the models. HRRR is closest with some
approximation of the line of showers and thunderstorms across
central ILX...and some reflection of the wave interacting with the
stalled boundary out in KS. NAM also trying to key in on
it...though it dissolves rather quickly in the HRRR, and the NAM
sends it further eastward, diving sw of ILX and interacting with
the boundary later tonight well out of ILX. More eastward
progression with that disturbance may well change the outcome of
the mid day and afternoon thunderstorm chances.
LONG TERM...Tuesday through Saturday...
Cooler air immediately behind the front begins to slowly warm back
up on Tuesday by a few degrees a day. Northwesterly flow dominates
and a deep low digging in a trof over the eastern half of the
CONUS. From mid week on, chances begin to increase with afternoon
instability showers under the deepening cyclonic flow aloft, with
a more stormy afternoon summer pattern. But will be very scattered
and low in coverage. Timing with the next wave diving into the
trof aloft bringing better chances...is lacking continuity in
models. End of the week have better chances for some rainfall...
but certainty and coverage will keep the chances low and diffuse.
HJS
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
1102 AM CDT SUN JUL 27 2014
.DISCUSSION...
322 AM CDT
SYNOPSIS...ONE MORE DAY OF A DIFFICULT AND MESSY PATTERN THAT WILL
RESULT IN SHOWERS AND THUNDERSTORMS ACROSS THE REGION. NO SEVERE
STORMS ARE EXPECTED. TEMPERATURES FALL THIS AFTERNOON AND REMAIN
BELOW NORMAL THROUGH THE REST OF THE WEEK. WE DRY OUT MONDAY AND
THEN HAVE LOW CHANCES OF PRECIP TUESDAY THROUGH SATURDAY.
TODAY AND TONIGHT...
AN UPPER LEVEL LOW IS OVER NORTHERN MINNESOTA WHILE A LARGER LOW IS
OVER NORTHERN QUEBEC. A SHORTWAVE TROUGH IS ALSO OVER EASTERN IOWA
WITH CONVECTION OVER CENTRAL WI. SPOTTY SHOWERS/SPRINKLES HAVE
SPROUTED OVER SOUTHEAST WI AND NOT EXPECTING MUCH ACTIVITY FROM
THOSE SPRINKLES. ADDITIONAL MORE IMPRESSIVE CONVECTION HAS FIRED
ALONG A WEAK BOUNDARY OVER CENTRAL IL. MAY SEE A FEW STORMS SOUTH OF
A PERU TO RENSSELAER LINE EARLY THIS MORNING.
FOG IS PRESENT OVER MUCH OF THE FORECAST AREA THIS MORNING AS
WELL. CLOUD COVER IS EXPANDING FROM SOUTH TO NORTH AND VSBY
INCREASES AS THE CLOUDS MOVE OVERHEAD. AS SUCH WILL HOLD OFF ON A
DENSE FOG ADVISORY FOR NOW AND SEE HOW THE CLOUD COVER SPREADS
ACROSS THE REGION.
EXPECTING ADDITIONAL CONVECTION TO FIRE AHEAD OF THE SHORTWAVE THIS
MORNING AND MOVE INTO NORTH CENTRAL IL. INSTABILITY MAY BE
LIMITED...BUT SOME THUNDER SHOULD BE REALIZED BASED ON
OBSERVATIONAL TRENDS UPSTREAM. THE SHOWERS AND STORMS WILL PUSH
EAST INTO THE AFTERNOON AS THE SHORTWAVE MOVES THROUGH. A COLD
FRONT CURRENTLY ACROSS NW WI THROUGH CENTRAL IA WILL ALSO
TRANSVERSE THE REGION AHEAD OF THE UPPER LEVEL LOW. THE LOW WILL
SWING OVER THE LAKE THIS AFTERNOON AND EXPECTING ADDITIONAL
ISOLATED TO SCATTERED STORMS WITH THIS FEATURE. TODAY WILL NOT BE
A WASH OUT HOWEVER AND THERE SHOULD BE PLENTY OF DRY HOURS.
ISOLATED SHOWERS CONTINUE INTO THE EVENING AND THEN THE BACK SIDE
OF THE UPPER LEVEL TROUGH SLIDES SOUTH THROUGH THE REGION
OVERNIGHT CLEARING OUT THE CLOUDS.
GUSTY WINDS ARE EXPECTED...AT TIMES TO 30 MPH THIS AFTERNOON.
WITH THE STRONG WINDS OVER LAKE MICHIGAN ORIENTED PARALLEL TO THE
FETCH...WAVES WILL BUILD CONSIDERABLY TONIGHT AND PERSIST INTO
MONDAY...AND A BEACH HAZARDS STATEMENT WILL GO INTO EFFECT FOR ALL
LAKE ADJACENT COUNTIES IN THE FORECAST AREA.
CLOUD COVER SHOULD STAY WITH US MOST OF THE DAY LIMITING HOW WARM WE
GET AGAIN. HIGHS WILL VARY FROM AROUND 80 NORTH TO THE MID 80S
SOUTH WHERE THERE COULD BE MORE SUNSHINE. TEMPS AND DEWPOINTS WILL
FALL THIS AFTERNOON THOUGH AS COOLER AIR MOVES IN BEHIND THE COLD
FRONT.
MONDAY...
THE UPPER LEVEL LOW WEAKENS TO AN OPEN TROUGH AND THEN MERGES WITH
THE STRONGER LOW OVER QUEBEC MONDAY NIGHT. WE STAY STUCK IN AN
UPPER LEVEL PATTERN WITH A RIDGE TO THE WEST AND TROUGH TO THE
EAST. THE SURFACE LOW MOVES OVER NEW ENGLAND MONDAY MORNING AND
HIGH PRESSURE BUILDS OVER THE PLAINS. MONDAY LOOKS DRY WITH WEAK
VORTICITY STREAMERS PASSING BY OVERHEAD. HIGHS WILL BE WELL BELOW
NORMAL IN THE LOW TO MID 70S. ONSHORE FLOW WILL KEEP THE LAKEFRONT
NEAR 70. THEN A BEAUTIFUL NIGHT FOR SLEEPING IS IN STORE WITH LOWS
IN THE MID 50S...EXCEPT FOR AROUND 60 DOWNTOWN.
TUESDAY THROUGH SATURDAY...
WE REMAIN IN THE STAGNANT UPPER LEVEL PATTERN WITH A SURFACE HIGH
OVER THE PLAINS. KEPT PERIODIC LOW CHANCES OF SHOWERS AND STORMS IN
THE EXTENDED FORECAST AS VORTICITY STREAMERS CONTINUE TO ROTATE
THROUGH THE REGION. MOISTURE IS NOT PLENTIFUL SO NOT EXPECTING MUCH
PRECIP AT THIS TIME. TEMPERATURES ALSO REMAIN BELOW NORMAL IN THE
70S WITH A FEW SITES MAYBE REACHING 80.
JEE
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 16Z...
* ISOLATED/SCATTERED TSRA 16Z-18Z.
* CHANCE OF SHRA THIS AFTERNOON INTO EARLY THIS EVENING.
* STRONG/GUSTY WEST/NORTHWEST WINDS LATE MORNING THRU THIS EVENING.
* NORTH/NORTHEAST WINDS MONDAY MORNING.
* POSSIBLE MVFR CIGS TONIGHT. CMS
//DISCUSSION...UPDATED 16Z...
FRONTAL BOUNDARY IS NOW PUSHING ACROSS THE CHICAGO METRO AREA AND
ANY TSRA THAT MAY FORM ALONG/AHEAD OF THIS FRONT WILL BE SHORT-
LIVED IN TERMS OF IMPACTS AT THE TERMINALS. HAVE TRIMMED TEMPO
DURATION AND ALSO VCTS DURATION...NOW ENDING AT ORD/MDW BY 18Z.
THOUGH ITS STILL POSSIBLE THAT A FAIRLY BROKEN/SOLID LINE OF TSRA
DEVELOPS EAST OF THE TERMINALS BY EARLY AFTERNOON. OTHERWISE...
WEST/NORTHWEST WINDS WILL CONTINUE TO INCREASE WITH GUSTS INTO THE
MID 20KT RANGE FOR MUCH OF THE AFTERNOON. CMS
PREVIOUS 12Z DISCUSSION...
HIGH MOISTURE VALUES OVER THE AREA WILL SUPPORT FOG/LOW CLOUDS
THROUGH 13Z-14Z AND MAYBE EVEN TO 15Z ACROSS THE REGION. WOULD NOT
EXPECT CONDITIONS TO GET WORSE AT TAF SITES AFTER 12Z GIVEN
DAYBREAK AND AN INCREASING WIND FLOW.
A STRONG UPPER LEVEL LOW PRESSURE MOVING INTO NORTHWEST WI AS OF
12Z WILL ROTATE SOUTHEASTWARD OVER CHICAGO BY MID-AFTERNOON. JUST
AHEAD OF THIS WILL EXIST A FAIR AMOUNT OF LIFT AND UPPER
SUPPORT...WHICH OVERRIDING A COLD FRONT WITH INSTABILITY ALONG IT
WILL LIKELY SUPPORT THE DEVELOPMENT OF A LINE OF SHRA/TSRA. HOW
FAR SOUTH THIS WILL EXTEND IS UNCERTAIN BUT AT THIS TIME BELIEVE
ENOUGH THAT IT WARRANTS INCLUSION INTO THE TAF. AS THE HEART OF
THE UPPER LOW MOVES OVER THE AREA DURING THE MID TO LATE
AFTERNOON...WOULD EXPECT SCATTERED SHOWERS WITH POSSIBLY ISOLATED
STORMS.
BEHIND THE COLD FRONTAL PASSAGE LATE THIS MORNING/EARLY
AFTERNOON...THERE WILL BE A SHARP INCREASE IN THE WIND SPEEDS
FROM THE WEST-NORTHWEST. OCCASIONAL GUSTS IN EXCESS OF 25 KT ARE
PROBABLE. A SECONDARY COLD FRONT DROPPING SOUTHWARD LATE THIS
AFTERNOON WILL LIKELY KEEP SOME GUSTS INTO THE EVENING PERIOD DUE
TO ITS COOL AIR ADVECTION. THIS FRONT WILL ALSO LIKELY PROVIDE
SOME FOCUS FOR MVFR OR NEAR-MVFR CLOUDS THIS EVENING INTO EARLY
OVERNIGHT.
//ORD AND MDW CONFIDENCE...UPDATED 16Z...
* LOW FOR TSRA 16Z-18Z.
* LOW FOR SHRA THIS AFTERNOON/EARLY EVENING.
* HIGH FOR WINDS THROUGH THIS AFTERNOON...MEDIUM TONIGHT/MONDAY.
* LOW FOR MVFR CIGS TONIGHT. CMS
//OUTLOOK FOR ORD/MDW FOR 00Z TUESDAY-12Z SUNDAY...UPDATED 12Z...
MONDAY NIGHT...VFR.
TUESDAY...SLIGHT CHANCE OF AFTERNOON TSRA.
WEDNESDAY...SLIGHT CHANCE OF TSRA.
THURSDAY-SATURDAY...SLIGHT CHANCES OF TSRA. NORTHEAST WINDS.
MTF
&&
.MARINE...
300 AM CDT
AN ACTIVE AND ATYPICAL SUMMERTIME PATTERN WILL UNFOLD ACROSS THE
LAKE THIS AFTERNOON THROUGH MONDAY NIGHT. LOW PRESSURE OVER THE
MIDDLE OF LAKE MICHIGAN BY MID TO LATE MORNING WILL MOVE EASTWARD
AND SLOWLY DEEPEN THIS AFTERNOON INTO TONIGHT. AS THIS OCCURS...COOL
AIR ADVECTION ON ITS BACKSIDE WITHIN A TIGHTENING PRESSURE
GRADIENT WILL DRIVE STRONG NORTHERLY WINDS. THESE WINDS LOOK TO
COME UP QUICKLY LATE THIS AFTERNOON AND BE MAXIMIZED THIS EVENING
INTO EARLY OVERNIGHT AND IT IS THEN WHEN OCCASIONAL GALE FORCE
GUSTS COULD OCCUR...ESPECIALLY OVER THE CENTRAL AND SOUTHERN PART
OF THE LAKE AND INTO THE INDIANA NEARSHORE. WINDS WILL BE SLOW TO
DIMINISH DURING MONDAY BUT THEN QUICKLY DROP MONDAY NIGHT. GIVEN
THE LONG FETCH THAT WILL BE REALIZED WAVES WILL BE ON THE UPPER
END OF THE SPECTRUM FOR SUMMERTIME WITH 7 TO 10 AND OCCASIONAL
HIGHER WAVES IN THE CENTRAL AND SOUTHERN PART OF THE LAKE INTO THE
INDIANA AND POSSIBLY ILLINOIS NEARSHORE AREAS. STRONG CANADIAN
HIGH PRESSURE FOR MID-SUMMER OVER THE NORTHERN PLAINS ON MONDAY
WILL EVOLVE EASTWARD OVER LAKE MICHIGAN BY MIDWEEK.
MTF
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...BEACH HAZARDS STATEMENT...ILZ014...10 PM SUNDAY TO 4 AM TUESDAY.
BEACH HAZARDS STATEMENT...ILZ006...10 PM SUNDAY TO 10 PM MONDAY.
IN...BEACH HAZARDS STATEMENT...INZ001-INZ002...6 PM SUNDAY TO 4 AM
TUESDAY.
LM...SMALL CRAFT ADVISORY...NEARSHORE WINTHROP HARBOR TO NORTHERLY IS `
UNTIL 10 PM MONDAY.
SMALL CRAFT ADVISORY...LMZ742-LMZ743 UNTIL 4 AM TUESDAY.
SMALL CRAFT ADVISORY...LMZ744-LMZ745...3 PM SUNDAY TO 4 AM
TUESDAY.
&&
$$
VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
WWW.FACEBOOK.COM/US.NATIONALWEATHERSERVICE.CHICAGO.GOV
WWW.TWITTER.COM/NWSCHICAGO
WWW.YOUTUBE.COM/NWSCHICAGO
Area Forecast Discussion
National Weather Service Lincoln IL
1046 AM CDT Sun Jul 27 2014
.DISCUSSION...
ISSUED 1045 AM CDT Sun Jul 27 2014
Forecast generally looks on track today and main adjustment is
low cloud cover lingering longer than earlier expected se of I-55.
Skies should still become partly to mostly sunny across central
and evenually eastern IL during the afternoon. Will continue
small chances of showers and thunderstorms over eastern IL mainly
east of I-57 this afternoon. SPC has slight risk of severe storms
from the IL/IN border east across IN/KY/OH with moderate risk over
in the foothills of the Appalachians in eastern KY and southern OH.
Cold front was pushing se into far southeast IL near the Wabash
River late this morning with WNW winds increasing behind the front
over central IL and gusting 15-25 mph over IL river valley. Still
muggy dewpoints in the low to mid 70s se of IL river and upper 60s
nw of IL river. Dewpoints drop off into the upper 50s and lower
60s upstream near the IA/IL border and should advect se into
central IL during the afternoon. Southeast IL will still be muggy
today where dewpoints currently in mid 70s but should slip into
the mid to upper 60s during the afternoon. Highs in the low to mid
80s look on track today with return of more sunshine with some
upper 80s near Lawrenceville.
07
&&
.AVIATION...
ISSUED 655 AM CDT Sun Jul 27 2014
Cold frontal boundary pushing into central IL roughly aligned from
KSPI-KAAA-KBMI as of 1130Z. Along the boundary a combination of a
shower band and locally dense fog is noted in surface obs and
radar imagery. Another hour or two of IFR-VLIFR vsby/cigs in fog
possible before daytime heating raises ceilings. Isold tsra will
remain possible in the vicinity of the boundary through this
afternoon causing isold mvfr vsby/cigs, but probabilities are too
low for mention in TAFs. Cloud cover becoming sct-bkn030-050
after 14Z. After 00Z- 02Z...clearing skies expected. Light winds
becoming NW and increasing to 12-18G20-25 kts through 18Z. Winds
becoming less gusty after 00Z and gradually decreasing overnight.
Onton
&&
.PREV DISCUSSION...
ISSUED 245 AM CDT Sun Jul 27 2014
Sfc map a mess in the wake of yesterday evenings convection. Broad
sfc trof/frontal boundary hung up over the region with light and
variable winds. Some patchy fog out there, with only a couple
sites dropping to a mile vis this morning. Some convection blowing
up over the area turning over some of the air and helping to block
much more of a vis drop in that area...and potentially limiting
the temp drop predawn. Even high res short term models not
handling the current conditions well, much less the next 12 hours.
Many mesoscale dynamics out there not being represented. Front
still not yet through the region...and first issue with the
forecast will be hanging on to pops, particularly in the east with
the frontal passage later mid day and this afternoon.
SHORT TERM...Today and tomorrow...
Keeping chances in for scattered showers and thunderstorms until
the front can progress through the area. Though today is expected
to get warm in front of the boundary...tomorrow is expected to see
signif cooler temps with some relatively drier air filtering in.
Precip chances drop out of the forecast for tonight and tomorrow.
But it bears mentioning that todays pops will be complicated by
small perturbations that are not being resolved well in the
models. HRRR is closest with some approximation of the line of
showers and thunder across central ILX...and some reflection of
the wave interacting with the stalled boundary out in KS. NAM also
trying to key in on it...though it dissolves rather quickly in the
HRRR, and the NAM sends it further eastward, diving sw of ILX and
interacting with the boundary later tonight well out of ILX. More
eastward progression with that disturbance may well change the
outcome of the mid day and afternoon ts chances.
LONG TERM...Tuesday through Saturday...
Cooler air immediately behind the front begins to slowly warm back
up on Tuesday by a few degrees a day. Northwesterly flow dominates
and a deep low digging in a trof over the eastern half of the
CONUS. From mid week on, chances begin to increase with afternoon
instability showers under the deepening cyclonic flow aloft, with
a more stormy afternoon summer pattern. But will be very scattered
and low in coverage. Timing with the next wave diving into the
trof aloft bringing better chances...is lacking continuity in
models. End of the week have better chances for some rainfall...
but certainty and coverage will keep the chances low and diffuse.
HJS
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS NORTHERN INDIANA
305 PM EDT SUN JUL 27 2014
.SYNOPSIS...
ISSUED AT 305 PM EDT SUN JUL 27 2014
SHOWERS AND THUNDERSTORMS ARE EXPECTED THIS AFTERNOON INTO EARLY
THIS EVENING AS A STRONG UPPER LEVEL DISTURBANCE AND COLD FRONT
DROP INTO THE LOWER GREAT LAKES. A FEW THUNDERSTORMS MAY BE SEVERE
WITH LARGE HAIL AND DAMAGING WINDS. MUCH COOLER AND DRIER AIR WILL
FILTER INTO THE REGION BEHIND THIS COLD FRONT TONIGHT INTO
MONDAY...WITH DRY CONDITIONS AND COOLER THAN NORMAL TEMPERATURES
EXPECTED FOR MUCH OF NEXT WEEK.
&&
.SHORT TERM...(THIS AFTERNOON THROUGH MONDAY)
ISSUED AT 305 PM EDT SUN JUL 27 2014
BROKEN CONVECTIVE LINE SEGMENTS/SUPERCELLS POTENTIALLY CONTAINING
LARGE HAIL AND DAMAGING WINDS REMAINS THE PRIMARY CONCERN THIS
AFTERNOON AS COLD FRONT ON LEADING EDGE OF COLD POCKET ALOFT EDGES
EAST OVER A VERY MOIST/UNSTABLE BOUNDARY LAYER. SVR WATCH 446 HAS
BEEN ISSUED FOR THE ENTIRE FA WITH CONVECTIVE LINE ALREADY INTO NW
INDIANA/SW LOWER MI AS OF 1830Z GIVEN MLCAPE EROSION WITH TEMPS
REACHING THE LOW/MID 80S ACROSS NORTHERN/WESTERN ZONES. RESULTING
SBCAPE RESERVOIR NEAR 3000 J/KG AMID 40-50 KNOTS OF DEEP LAYER
SHEAR FAVORS ORGANIZATION AND THIS HAIL/WIND THREAT. THE TORNADO
RISK REMAINS LOW GIVEN MEAGER 0-1 KM HELICITY/SHEAR VALUES.
OTHERWISE...EXPECT A FEW SHOWERS/EMBEDDED THUNDER TO LINGER
ACROSS MAINLY NORTHERN PORTIONS OF THE FA INTO THIS EVENING UNDER
A COMPACT CLOSED LOW FCST TO DROP SOUTHEAST THROUGH THE LOWER
LAKES FROM CENTRAL WI.
CAA REGIME IN DEEPENING NNW FLOW IN WAKE OF THIS VIGOROUS
SHORTWAVE/CDFNT SHOULD ENSURE DRY/MUCH COOLER WEATHER LATER TONIGHT
INTO MONDAY.
&&
.LONG TERM...(MONDAY NIGHT THROUGH SUNDAY)
ISSUED AT 305 PM EDT SUN JUL 27 2014
STEADY STATE AMPLIFIED FLW REGIME XPCD TO CONT THROUGH THIS
PD...ANCHORED OUT WEST BY UPR RIDGE EXTNDG NWD THROUGH SWRN CANADA
AND EAST BY DEEP UPR LOW CNTRD NR JAMES BAY. AS A RESULT XPC CONTD
DRY NWRLY LL FLW AND PLEASANT TEMPERATURES THROUGH THE PD.
SOME CONVOLUTED SUGGESTION IN SOME MED RANGE GUIDANCE OF TERTIARY
DISTURBANCES WRAPPING THROUGH THE BASE OF MID LVL THROUGH CNTRD
THROUGH THE ERN LAKES...PARTICULARLY THE OP GFS DEPICTION ON TUE/
WED. HWVR IT STANDS ALONE IN DROPPING A SW DISTURBANCE WELL SWD OF
ANY OTHER GUIDANCE. AS SUCH WILL HOLD W/DRY WX THROUGHOUT.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON)
ISSUED AT 1257 PM EDT SUN JUL 27 2014
IFR/LOW MVFR CIGS AT FWA ALONG LEFTOVER CONVERGENT MOISTURE
BOUNDARY SHOULD MIX OUT TO A HIGH MVFR/LOW VFR STRATOCU DECK
SHORTLY AFTER TAF ISSUANCE. SBN ALREADY WELL MIXED IN ADVANCE OF
IMPRESSIVE MID LVL TROUGH AXIS THAT WILL DROP SOUTHEAST INTO THE
AREA THIS AFTERNOON. EXPECT AT LEAST SCT CONVECTION TO DEVELOP ON
LEADING EDGE OF COLD POCKET ALOFT WITH TEMPO TSRA TIMING BASED
LARGELY ON LAST FEW HRRR ITERATIONS. STORMS COULD BECOME SEVERE
WITH LARGE HAIL/STRONG GUSTS...BETTER CHANCES AT FWA. A PERIOD OF
MAINLY VFR/DRY CONDITIONS EXPECTED IN WAKE OF CONVECTION LATE THIS
AFTERNOON/EVENING BEFORE LOW CLOUDS IN CAA/WRAP AROUND MOISTURE
REGIME SINK IN OVERNIGHT INTO MONDAY MORNING.
&&
.IWX WATCHES/WARNINGS/ADVISORIES...
IN...BEACH HAZARDS STATEMENT FROM 7 PM CDT THIS EVENING THROUGH LATE
MONDAY NIGHT FOR INZ003.
MI...BEACH HAZARDS STATEMENT FROM 8 PM EDT THIS EVENING THROUGH LATE
MONDAY NIGHT FOR MIZ077.
OH...NONE.
LM...SMALL CRAFT ADVISORY FROM 8 PM THIS EVENING TO 5 AM EDT TUESDAY
FOR LMZ043-046.
&&
$$
SYNOPSIS...STEINWEDEL
SHORT TERM...STEINWEDEL
LONG TERM...T
AVIATION...STEINWEDEL
VISIT US AT WWW.WEATHER.GOV/IWX (ALL LOWER CASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
WWW.FACEBOOK.COM/NWSNORTHERNINDIANA
WWW.TWITTER.COM/NWSIWX
WWW.YOUTUBE.COM/NWSNORTHERNINDIANA
AREA FORECAST DISCUSSION
NWS NORTHERN INDIANA
1257 PM EDT SUN JUL 27 2014
.SYNOPSIS...
ISSUED AT 435 AM EDT SUN JUL 27 2014
AS A COLD FRONTAL BOUNDARY APPROACHES THE AREA THERE IS AN
INCREASED CHANCE FOR SHOWERS AND THUNDERSTORMS FROM MIDDAY INTO
EARLY THIS AFTERNOON AS A STRONGER UPPER LEVEL DISTURBANCE DROPS
INTO THE WESTERN GREAT LAKES. THE FRONTAL BOUNDARY ASSOCIATED
WITH THIS DISTURBANCE WILL PROVIDE DRY AND COOLER THAN NORMAL
CONDITIONS THROUGH MUCH OF NEXT WEEK.
&&
.UPDATE...
ISSUED AT 1023 AM EDT SUN JUL 27 2014
RAISED POPS INTO THE EARLY AFTERNOON ALONG/SOUTHEAST OF HWY 24 IN
IN/OH PER RADAR/SATELLITE TRENDS AS SHOWERS/ISO THUNDER BEGINNING
TO GROW IN COVERAGE ALONG REMNANT CONVERGENT BOUNDARY. A LOW END
THREAT FOR SVR HAIL EXISTS WITH THIS ACTIVITY.
THE MAIN FOCUS REMAINS ON SEVERE POTENTIAL THIS AFTERNOON AS
LEADING EDGE OF SIG HEIGHT FALLS/COLD POOL ALOFT OVERSPREADS MOIST
LOW LEVEL AIRMASS IN PLACE. LOW STRATUS DECK LINGERING OVER THE
AREA APPEARS RATHER THIN AND MAY SCATTER OUT ENOUGH TO ERODE MORE
SIGNIFICANT MLCIN IN PLACE. IF THIS WERE TO OCCUR CONDITIONS WOULD
BECOME FAVORABLE FOR BROKEN CONVECTIVE LINE SEGMENTS TO DEVELOP
AND GROW UPSCALE ESE THROUGH THE FORECAST AREA BTW 19-23Z.
MODERATE INSTABILITY (STILL SOMEWHAT UNCERTAIN) AND STRONG DEEP
LAYER SHEAR (50 KTS...HIGH CONFIDENCE) DEFINITELY SUGGEST A SEVERE
WIND/HAIL THREAT AND POSSIBLY A LOW TORNADO THREAT IF ANY
BOWING/ORGANIZATION OCCURS. WITH INCREASING CONFIDENCE OPTED TO
ADD A SEVERE MENTION TO THE GRIDS AND BUMP POPS INTO LIKELY.
OTHERWISE...ONLY MINOR TWEAKS MADE TO THE GRIDS/HWO.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 432 AM EDT SUN JUL 27 2014
DIFFICULTY CENTERED UPON CONVECTION POTENTIAL TODAY. LARGE CONGEALED
COLD POOL PUSH SEWD FROM SAT AFTERNOON CONVECTION ACRS NERN IN/NWRN
OH FOLLOWED BY WAKE OF MID MS VLY TO LWR OH VLY COMPLEX...HAS LEFT
CWA AMID STRONG MLCIN ON ORDER OF 100-200 J/KG. CONVECTION FIRING
ALONG WEAKNESS IN EML THROUGH CENTRAL ILLINOIS WITHIN HIGHLY
CONVERGENT 925-8H MB FLOW OWING TO WEAK FRONTAL WAVE OVR WCNTL IL
AND RAMPING WSWLY LLVL JETLET TO 40-45 KTS ALONG MISSOURI I70
CORRIDOR. PRIMARY CLUSTER TO TRACK INTO CENTRAL INDIANA...THOUGH
WEAKER CONVECTION FARTHER NORTH/VCNTY KPNT MAY CLIP FAR SWRN/SRN CWA
LATER THIS AM. RAMPING CONVECTIVE CHCS BY LATE MORNING WITH APPROACH
OF SECONDARY FRONTAL BOUNDARY TO DROP SEWD ASSOCD WITH INTENSE MID
TROPOSPHERIC VORTEX OVR NRN MN MOVING TO NEAR SAGINAW BAY BY 00 UTC
MON. HIGH NEAR SURFACE MOISTURE CONTENT POOLED THROUGHOUT HIGHLY
EFFICIENT EVAPOTRANSPIRATIVE CORN BELT LEADING TO WIDESPREAD
STRATUS/BR PATCHY DENSE FOG DEVELOPMENT THIS AM. CONCERN THAT LESS
THAN STELLAR MORNING INSOLATION TO LIMIT OVERALL INSTABILITY ACROSS
PREFRONTAL REGION. STILL BY MIDDAY MODIFIED NAM12 SOUNDINGS OF NEAR
80/LWR 70S SUPPORT NEAR 3000 J/KG SBCAPE. LEADING EDGE OF
SIGNIFICANT 60-80M/12 HR HEIGHT FALLS ALONG WITH STRONG KINEMATIC
PROFILE WITH SLIGHT VEERING /DEEP LAYER SHEAR VECTORS ON ORDER OF
40-50KTS/ COULD PROMOTE UPSCALE CONVECTIVE GROWTH IN PREFRONTAL ZONE
MIDDAY INTO EARLY THIS AFTERNOON IN NW THROUGH SE FASHION. PRESENCE
OF MID LEVEL DRY AIR ALONG WITH MDPI AROUND 1.1/WINDEX GTE 50KTS
SUGGEST ISOLD DAMAGING WIND POTENTIAL. FAVORABLE WETBULB ZERO
HEIGHTS NEAR 11.5 KFT WOULD ALSO SUPPORT HAIL PRODUCTION SHOULD
HIGHER END CAPE VALUES BE REALIZED. GIVEN SOME UNCERTAINTY WITH
REGARD TO DEGREE OF INSTABILITY AND MESOSCALE INTRICACIES...WILL
RELEGATE MENTION OF SEVERE POTENTIAL TO HWO. LOWERED MAX TEMPS TODAY
A FEW DEGREES/CLOSER TO 3 HOURLY TEMPS NUDGED TOWARD LATEST GUIDANCE
BLENDS.
&&
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 432 AM EDT SUN JUL 27 2014
UPPER LOW NEAR JAMES BAY WILL REMAIN STATIONARY FOR FIRST FEW
DAYS BEFORE EDGING SLOWLY NE TOWARDS THE END OF THE PERIOD. WILL
BLEND WITH SHORT TERM FOR START OF PERIOD WITH REMOVAL OF SLGT CHC
POPS FAR EAST AS SYSTEM AND DEEPEST MSTR WILL BE GONE BY THE START
OF THE PERIOD. GENERAL NW FLOW WILL KEEP TEMPS RUNNING 10 DEGREES OR
SO BELOW NORMAL BUT STILL PLEASANT FOR THE END OF JULY. MODELS DO
ALL AGREE ON A WEAK (578 DM) UPPER LEVEL LOW CUTTING OFF FROM THE
MAIN FLOW LATE IN THE PERIOD WITH SEVERAL WEAK DISTURBANCES TO MOVE
INTO THE GREAT LAKES. CHANCES FOR SHOWERS/STORMS COULD MATERIALIZE
STARTING AS EARLY AS WEDS/WEDS NGT BUT DEEPER MOISTURE WILL REMAIN
WELL SOUTH OF THE REGION WITH ONLY HOPE FOR INCREASE OCCURRING FROM
PACIFIC FLOW THAT MAY RIDE OVER TOP THE RIDGE INTO THE GREAT LAKES.
500 MB TEMPS WILL DROP TO THE MID NEGATIVE TEENS BUT SHIFT NE OF THE
AREA AS ANY MOISTURE ARRIVES. GIVEN THESE CONCERNS AND QUESTION AS
TO TIMING AND EXACT DYNAMICS WITH EACH WAVE TOUGH TO MUDDLE FORECAST
WITH A BUNCH OF SLGT CHC OR BORDERLINE CHC POPS. 00Z MEN NUMBERS
ALSO COMING IN GENERALLY BELOW CLIMO...GIVING MORE CREDENCE TO DRY
FORECAST FOR THE TIME BEING.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON)
ISSUED AT 1257 PM EDT SUN JUL 27 2014
IFR/LOW MVFR CIGS AT FWA ALONG LEFTOVER CONVERGENT MOISTURE
BOUNDARY SHOULD MIX OUT TO A HIGH MVFR/LOW VFR STRATOCU DECK
SHORTLY AFTER TAF ISSUANCE. SBN ALREADY WELL MIXED IN ADVANCE OF
IMPRESSIVE MID LVL TROUGH AXIS THAT WILL DROP SOUTHEAST INTO THE
AREA THIS AFTERNOON. EXPECT AT LEAST SCT CONVECTION TO DEVELOP ON
LEADING EDGE OF COLD POCKET ALOFT WITH TEMPO TSRA TIMING BASED
LARGELY ON LAST FEW HRRR ITERATIONS. STORMS COULD BECOME SEVERE
WITH LARGE HAIL/STRONG GUSTS...BETTER CHANCES AT FWA. A PERIOD OF
MAINLY VFR/DRY CONDITIONS EXPECTED IN WAKE OF CONVECTION LATE THIS
AFTERNOON/EVENING BEFORE LOW CLOUDS IN CAA/WRAP AROUND MOISTURE
REGIME SINK IN OVERNIGHT INTO MONDAY MORNING.
&&
.MARINE...
ISSUED AT 432 AM EDT SUN JUL 27 2014
STRONG 3-6MB/6 HOUR POST FRONTAL PRESSURE RISES TO DROP SWD FROM
NRN MN/WRN LAKE SUPERIOR INTO LOWER OHIO VALLEY TONIGHT. THIS WILL
LEAD TO RAMPING NWRLY FLOW WITH GUSTS PEAKING AT OR JUST BELOW
GALE FORCE OVERNIGHT. WINDS CONTINUE TO VEER NORTHERLY ON
MONDAY...YIELDING LONG DURATION SMALL CRAFT ADVISORY CONDITIONS
AND VERY HIGH RIP CURRENT POTENTIAL THROUGH AT LEAST LATE MONDAY
NIGHT AS FLOW BEGINS TO RELAX.
&&
.IWX WATCHES/WARNINGS/ADVISORIES...
IN...BEACH HAZARDS STATEMENT FROM 7 PM CDT THIS EVENING THROUGH LATE
MONDAY NIGHT FOR INZ003.
MI...BEACH HAZARDS STATEMENT FROM 8 PM EDT THIS EVENING THROUGH LATE
MONDAY NIGHT FOR MIZ077.
OH...NONE.
LM...SMALL CRAFT ADVISORY FROM 8 PM THIS EVENING TO 5 AM EDT TUESDAY
FOR LMZ043-046.
&&
$$
UPDATE...STEINWEDEL
SYNOPSIS...MARSILI
SHORT TERM...MURPHY
LONG TERM...FISHER
AVIATION...STEINWEDEL
MARINE...MURPHY
VISIT US AT WWW.WEATHER.GOV/IWX (ALL LOWER CASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
WWW.FACEBOOK.COM/NWSNORTHERNINDIANA
WWW.TWITTER.COM/NWSIWX
WWW.YOUTUBE.COM/NWSNORTHERNINDIANA
AREA FORECAST DISCUSSION
NWS GOODLAND KS
240 PM MDT SUN JUL 27 2014
.SHORT TERM...(THIS AFTERNOON THROUGH MONDAY)
ISSUED AT 212 PM MDT SUN JUL 27 2014
EARLY AFTERNOON WV IMAGERY AND RAP UPPER LEVEL ANALYSIS SHOW RIDGE
CENTERED NEAR THE TX PANHANDLE EXTENDING FROM THE CANADIAN ROCKIES
TO THE SOUTHERN MISSISSIPPI VALLEY. AT THE SURFACE HIGH PRESSURE IS
IN PLACE ROM THE NORTHERN PLAINS INTO WESTERN KS...WITH A STATIONARY
FRONT ALONG THE FRONT RANGE AND ACROSS THE TX PANHANDLE.
THIS FRONT ALONG WITH HIGHER TERRAIN IN COLORADO WILL BE THE MAIN
FOCUS FOR THUNDERSTORM ACTIVITY THIS AFTERNOON THROUGH MONDAY. WITH
THE FRONT EXPECTED TO REMAIN WELL SOUTH AND WEST ...IM SKEPTICAL WE
ARE GOING TO SEE ANY SHOWERS/THUNDERSTORMS IN OUR CWA. IF WE DO IT
WOULD BE IN OUR SW LATE THIS AFTERNOON/EVENING WHERE THERE IS SOME
INSTABILITY IN PLACE...HOWEVER THIS THREAT WILL LIKELY BE DIURNAL
WITH NO OTHER LARGE SCALE FORCING IN PLACE LOCALLY. BY MIDDAY MONDAY
THE FRONT BEGINS TO LIFT NORTH WHICH WOULD RESULT IN INCREASING
SHOWER/THUNDERSTORM CHANCES IN THE WEST-SOUTHWEST...WHICH COULD ALSO
LIMIT DAYTIME HEATING. I TRENDED POPS BACK A LITTLE THROUGH TONIGHT
AND LIMITED THEM TO THE SOUTHWEST. I KEPT 20/30 POPS IN PLACE MONDAY
AFTERNOON AND TRENDED HIGHS DOWN A LITTLE IN THE SOUTHWESTERN CWA.
BETTER QPF/PRECIP SIGNAL IS LATER MONDAY AFTERNOON AND REALLY MONDAY
NIGHT...SO THERE MIGHT NOT BE TOO MUCH OF AN IMPACT ON TEMPS. HIGHS
MONDAY SHOULD BE SEASONAL WITH VALUES IN THE UPPER 80S ACROSS MUCH
OF THE CWA...WHILE LOCATIONS WITH THICKER CLOUD COVER (OR
PRECIPITATION) MAY BE CLOSER TO THE LOW-MID 80S. NOT VERY FAR OFF
FROM TODAY.
.LONG TERM...(MONDAY NIGHT THROUGH SUNDAY)
ISSUED AT 240 PM MDT SUN JUL 27 2014
MONDAY NIGHT-WEDNESDAY...NEAR TERM MODELS REMAIN IN REASONABLE
AGREEMENT WITH RESPECT TO THE LARGE SCALE PATTERN THROUGH THE START
OF THE WEEK. CWA WILL REMAIN ON NORTHEAST SIDE OF LARGE H5 RIDGE
WITH SEVERAL LOW AMPLITUDE DISTURBANCES MOVING THROUGH THE AREA.
COOLER TEMPERATURES AND SEVERAL PERIODS OF PRECIPITATION ARE
EXPECTED THROUGH THE PERIOD. OVERALL...BEST CHANCES FOR SIGNIFICANT
PRECIPITATION CONTINUE TO BE ON TUESDAY EVENING AS STRONG SHORT WAVE
TROUGH MOVES THROUGH PORTION OF RIDGE AXIS AND INTO THE CWA. LOOKS
LIKE PROFILES ARE ALL FAIRLY MOIST THROUGHOUT THE SOUNDINGS SO DO
NOT ANTICIPATE MOISTURE ADVECTION BEING A LIMITING FACTOR ON PRECIP
THREAT. DO HAVE SOME CONCERNS WITH RESPECT TO PRECIP PLACEMENT WITH
RESPECT TO SOME LOWER LEVEL TEMP ADVECT REGIMES....BUT GIVEN THE
OVERALL SUBTLE NATURE OF THE FORCING AMONGST THE LARGE SCALE RIDGE
AND ROLE INSTABILITY WILL PLAY IN DEVELOPMENT...DO NOT FEEL THIS
PATTERN IS ONE WHERE STRAYING GREATLY FROM CONSENSUS DATA IS
WARRANTED. SOME POTENTIAL FOR HEAVY RAIN WITH PWATS IN EXCESS OF 1.5
AND PERSISTENT DEFORMATION ZONE AROUND H7 ACROSS SOUTHERN CWA.
IN THE EXTENDED(WED NIGHT-SUNDAY)...COOLER PATTERN WILL CONTINUE
THROUGH THE PERIOD WITH PRECIP CHANCES WANING AS THE WEEK GOES ON
DUE TO PERSISTENT NORTHERLY FLOW. A LARGE RANGE IN EXPECTED
TEMPERATURE VALUES BETWEEN THE GFS AND ECMWF WITH THE LATTER BEING
SEVERAL DEGREES COOLER. WITH GEFS MEAN SLP INDICATING SFC HIGH
PRESSURE DOMINATING THE PATTERN...AM LEANING TOWARDS COOLER OUTPUT.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON)
ISSUED AT 1111 AM MDT SUN JUL 27 2014
VFR CONDITIONS WILL PREVAIL THROUGH THE TAF PERIOD AT BOTH KGLD
AND KMCK. THUNDERSTORMS WILL BE POSSIBLE MAINLY ACROSS EASTERN
COLORADO THIS AFTERNOON THROUGH TONIGHT...AND WHILE I CANT
COMPLETELY RULE OT AN ISOLATED THUNDERSTORM AT KGLD...CONFIDENCE
IS LOW THIS ACTIVITY WILL MAKE IT WITHIN THE VICINITY OF THE
TERMINAL. WINDS EARLY IN THE TAF PERIOD MAY OCCASIONALLY GUST FROM
THE EAST-NORTHEAST TO 20KT DURING THE FIRST HOUR OR SO OF THE TAF
PERIOD...WINDS WILL EVENTUALLY BECOME LIGHT AND VARIABLE AROUND
5KT AND THEN SHIFT TO THE SOUTHEAST AROUND 10KT MONDAY MORNING AS
SURFACE HIGH MOVES ACROSS THE AREA.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
SHORT TERM...DR
LONG TERM...JRM
AVIATION...DR
AREA FORECAST DISCUSSION
NWS GOODLAND KS
212 PM MDT SUN JUL 27 2014
.SHORT TERM...(THIS AFTERNOON THROUGH MONDAY)
ISSUED AT 212 PM MDT SUN JUL 27 2014
EARLY AFTERNOON WV IMAGERY AND RAP UPPER LEVEL ANALYSIS SHOW RIDGE
CENTERED NEAR THE TX PANHANDLE EXTENDING FROM THE CANADIAN ROCKIES
TO THE SOUTHERN MISSISSIPPI VALLEY. AT THE SURFACE HIGH PRESSURE IS
IN PLACE ROM THE NORTHERN PLAINS INTO WESTERN KS...WITH A STATIONARY
FRONT ALONG THE FRONT RANGE AND ACROSS THE TX PANHANDLE.
THIS FRONT ALONG WITH HIGHER TERRAIN IN COLORADO WILL BE THE MAIN
FOCUS FOR THUNDERSTORM ACTIVITY THIS AFTERNOON THROUGH MONDAY. WITH
THE FRONT EXPECTED TO REMAIN WELL SOUTH AND WEST ...IM SKEPTICAL WE
ARE GOING TO SEE ANY SHOWERS/THUNDERSTORMS IN OUR CWA. IF WE DO IT
WOULD BE IN OUR SW LATE THIS AFTERNOON/EVENING WHERE THERE IS SOME
INSTABILITY IN PLACE...HOWEVER THIS THREAT WILL LIKELY BE DIURNAL
WITH NO OTHER LARGE SCALE FORCING IN PLACE LOCALLY. BY MIDDAY MONDAY
THE FRONT BEGINS TO LIFT NORTH WHICH WOULD RESULT IN INCREASING
SHOWER/THUNDERSTORM CHANCES IN THE WEST-SOUTHWEST...WHICH COULD ALSO
LIMIT DAYTIME HEATING. I TRENDED POPS BACK A LITTLE THROUGH TONIGHT
AND LIMITED THEM TO THE SOUTHWEST. I KEPT 20/30 POPS IN PLACE MONDAY
AFTERNOON AND TRENDED HIGHS DOWN A LITTLE IN THE SOUTHWESTERN CWA.
BETTER QPF/PRECIP SIGNAL IS LATER MONDAY AFTERNOON AND REALLY MONDAY
NIGHT...SO THERE MIGHT NOT BE TOO MUCH OF AN IMPACT ON TEMPS. HIGHS
MONDAY SHOULD BE SEASONAL WITH VALUES IN THE UPPER 80S ACROSS MUCH
OF THE CWA...WHILE LOCATIONS WITH THICKER CLOUD COVER (OR
PRECIPITATION) MAY BE CLOSER TO THE LOW-MID 80S. NOT VERY FAR OFF
FROM TODAY.
.LONG TERM...(WEDNESDAY THROUGH SATURDAY)
ISSUED AT 204 AM MDT SUN JUL 27 2014
UPPER AND LOWER LEVEL FLOW WILL REMAIN QUIET FOR THE LONG TERM
PERIOD AS A DOMINANT UPPER LEVEL RIDGE WILL KEEP MAIN JET FLOW WELL
TO THE NORTH OF THE TRI STATE AREA. HOWEVER...MODEL SOUNDINGS
CONTINUE TO INDICATE AMPLE PROFILE MOISTURE ACROSS THE AREA FOR
WEDNESDAY AND THE FIRST HALF OF THURSDAY. PRECIPITABLE WATER
AMOUNTS BETWEEN 1.25 AND 1.5 INCHES WILL BE PRESENT AREA WIDE AS
LOWER LEVEL EASTERLY FLOW IS BELOW NORTHERLY FLOW ABOVE 700 MB. THE
COLDER AIR ADVECTION ABOVE 700 MB IN COMBINATION WITH MOISTURE
ADVECTION IN THE LOWER ATMOSPHERE WILL BRING WIDESPREAD CHANCES FOR
PRECIPITATION FOR WEDNESDAY INTO THURSDAY.
DRIER AIR WILL MOVE INTO THE HIGH PLAINS THURSDAY EVENING AS WINDS
BELOW 800 MB SHIFT TO THE SOUTHWEST...WHICH SHOULD END WIDESPREAD
PRECIPITATION CHANCES THROUGH FRIDAY MORNING. WARM AIR ADVECTION
AND A ZONE OF CONFLUENCE OVER THE FORECAST AREA COMBINED WITH SOME
CAPE ALOFT FRIDAY AFTERNOON COULD SPARK SOME THUNDERSTORM
DEVELOPMENT IN EASTERN COLORADO INTO FRIDAY EVENING. A SURFACE
BOUNDARY JUST TO THE SOUTH OF THE FORECAST AREA WILL BRING CHANCES
FOR SHOWERS AND THUNDERSTORMS SATURDAY FOR LOCATIONS SOUTH OF
INTERSTATE 70.
THE COOLER AIR ADVECTION IN THE MID LEVELS WILL BRING BELOW AVERAGE
TEMPERATURES TO THE REGION FOR WEDNESDAY AND THURSDAY...WITH HIGHS
RANGING FROM THE MID 70S TO THE LOWER 80S. HIGH TEMPERATURES WILL
REBOUND WITH WARM AIR RETURNING ON FRIDAY AND SATURDAY...WITH HIGHS
IN THE MID 80S. LOW TEMPERATURES THROUGH THE PERIOD WILL BE ABOUT
NORMAL IN THE LOW TO MID 60S.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON)
ISSUED AT 1111 AM MDT SUN JUL 27 2014
VFR CONDITIONS WILL PREVAIL THROUGH THE TAF PERIOD AT BOTH KGLD
AND KMCK. THUNDERSTORMS WILL BE POSSIBLE MAINLY ACROSS EASTERN
COLORADO THIS AFTERNOON THROUGH TONIGHT...AND WHILE I CANT
COMPLETELY RULE OT AN ISOLATED THUNDERSTORM AT KGLD...CONFIDENCE
IS LOW THIS ACTIVITY WILL MAKE IT WITHIN THE VICINITY OF THE
TERMINAL. WINDS EARLY IN THE TAF PERIOD MAY OCCASIONALLY GUST FROM
THE EAST-NORTHEAST TO 20KT DURING THE FIRST HOUR OR SO OF THE TAF
PERIOD...WINDS WILL EVENTUALLY BECOME LIGHT AND VARIABLE AROUND
5KT AND THEN SHIFT TO THE SOUTHEAST AROUND 10KT MONDAY MORNING AS
SURFACE HIGH MOVES ACROSS THE AREA.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
SHORT TERM...DR
LONG TERM...MK
AVIATION...DR
AREA FORECAST DISCUSSION
NWS PADUCAH KY
257 PM CDT Sun Jul 27 2014
.SHORT TERM...(Tonight through Tuesday night)
Issued at 257 PM CDT SUN JUL 27 2014
There are a couple of surface boundaries of note this afternoon.
The cold front was approaching the Wabash and Ohio Rivers, and it
marks the back edge of the hot air. Unfortunately, the 70
dewpoints extend quite a way to the northwest to another more
subtle wind shift extending from just north of STL to the southern
tip of Lake Michigan.
Along and south of the cold front, heat indices have climbed to
105 and even a bit above. With little cooling expected, have
already issued a Heat Advisory til 00Z. The winds on both sides of
the front have not materialized as forecast, so to keep the
headline clutter down, have cancelled the Lake Wind Advisory.
The thermonuclear cap appears to have effectively shut down any
potential for convection with the cold front this afternoon. The
latest HRRR actually tries to build storms westward along it across
TN this evening, keeping our area dry. Convection along the dewpoint
boundary over east central Illinois is moving east and there is no
sign of it developing farther south toward our northern
territories. Will continue to monitor for southwestward
development, but will keep the grids dry for now.
The dry, cool surface high pressure will eventually push the soup
out of our region tonight, and northerly winds will be the rule
into Tuesday. Had to fabricate some sky grids to account for the
extensive stratocu expected to overspread the area Monday.
Otherwise, there is little to discuss about the short term
forecast.
As for temperatures, stayed close to consensus guidance for lows
tonight and Monday night, but went below guidance Tuesday night,
when the best radiational cooling is expected. For highs, undercut
guidance Monday with significant cloud cover at least through the
afternoon. Didn`t stray too far from consensus for highs on
Tuesday.
.LONG TERM...(Wednesday through Sunday)
Issued at 257 PM CDT SUN JUL 27 2014
Above medium confidence in the extended with decreasing certainty
into the weekend.
Although there is still some run to run discontinuity especially
with the GFS. The models are consistently decreasing pops late week
and into the weekend. However the operational GFS come into much
better agreement with the upper level trough late in the week. Its
previous run indicated a slower cut off upper low over the lower
Ohio Valley. Now the 12z Sunday run shows a progressive open low
lifting out of the area quickly. This would be a reflection of the
lower pops from the extended init. Also with a north wind
predominant through the week with some easterly flow at
times...would not expect to advect adequate moisture for a
widespread rain event. However with a major upper level trough
swinging through and dew points in the 60s combined with daytime
heating could yield at least chance or slight chance for
thunderstorms.
Tweaked temps down a degree or two from what the extended init
yielded mostly for collaboration purposes.
&&
.AVIATION...
Issued at 1223 PM CDT SUN JUL 27 2014
It appears at this time that any convection today is likely to be
south and east of the terminals. The thick cu deck should settle
in at VFR levels, and it should generally thin out through the
afternoon. The cold frontal wind shift will take winds to the west
northwest at KCGI and KEVV right at the beginning of the period,
and KPAH and KOWB through the afternoon. As winds become northwest
mixing may take gusts up above 20kts at times. The main issue for
tomorrow will be an expansive stratocu deck as the cooler air
aloft advects over the region. Cannot rule out some MVFR ceilings
at KEVV and KOWB in the late morning.
&&
.PAH WATCHES/WARNINGS/ADVISORIES...
IL...HEAT ADVISORY until 7 PM CDT this evening FOR ILZ090>094.
MO...HEAT ADVISORY until 7 PM CDT this evening FOR MOZ108>112-114.
IN...NONE.
KY...HEAT ADVISORY until 7 PM CDT this evening FOR KYZ001>022.
&&
$$
SHORT TERM...DRS
LONG TERM...KH
AVIATION...DRS
AREA FORECAST DISCUSSION
NWS LOUISVILLE KY
107 PM EDT Sun Jul 27 2014
...Updated Aviation Discussion...
...Mesoscale Update...
Issued at 1225 PM EDT Sun Jul 27 2014
Latest thinking continues to remain on track. Current severe
convection across east-central KY is likely still elevated in
nature, given surface temperatures only in the upper 60s and lower
70s. This convection will mainly pose a large hail (possibly golf
ball sized at times) and isolated damaging wind threat.
A rather volatile airmass is advecting into south-central KY,
however, as peaks of sunshine have broke out (Bowling Green at
91/72). The prefrontal trough will interact with this airmass later
this afternoon, which should be enough to weaken the cap and
intiaite scattered supercells, mainly across south-central KY. The
latest runs of the HRRR continues to support this thinking. These
supercells will be capable of large hail (potentially 2+ inches) and
damaging winds. There will also be an isolated tornado threat given
the low-level speed shear and the lingering outflow boundaries that
storms may be able to interact with.
.SHORT TERM (Now through Monday)...
Issued at 359 AM EDT Sun Jul 27 2014
...Severe weather threat continues this morning through much of
today...
Currently:
The MCS that rolled through the forecast area late Saturday night
has not stopped convection from re-firing in a line extending
currently from roughly Daviess County, IN southeastward through
Elizabethtown, KY. These storms have developed near theta-e
advecting in from the west, along with an increase of low-level
PWATs, per the CIMMS NearCast model. This cluster has all of the
features of being severe; however, latest available AMDAR soundings
show a shallow stable layer, which may help to keep the worst of the
winds aloft. Regardless, the concern is certainly there that despite
that these storms should be primarily elevated, they seem to be able
to overcome the layer and go surface-based. An additional concern
that was not present with the previous MCS is that a directional
shear component has been added to the increase in speed shear as the
low-level jet ramps up and surface southerly winds persist.
Today:
Continued uncertainty exists for the exact evolution of today`s
storms, although given how easily convection was able to develop
overnight and how quickly the local atmosphere was able to recover
behind the MCS, this is concerning given all of the other parameters
that will line up to create a severe threat for much of central KY
and south-central IN. The worked over atmosphere has not stopped
storm development. Models are showing 0-6km bulk shear today will be
increasing from approximately 30kts. in southern KY to 50kts. north
of the Ohio River to 40kts in the south to 60kts. in the north by
late today. SBCAPE, while some already exists this morning, will
increase to over 2500 J/kg under the sun today. The focus of where
storms will develop and how they`ll move will be a short-term,
mesoscale based forecasting approach as they ride leftover
boundaries and wherever the greater instability sets up, which
currently looks to be in southern and eastern KY. Hi-res models are
showing multiple rounds of storms but clearing out by late this
afternoon. Think this will be more dependent on the timing of the
front. The mode early on could be discrete supercells, congealing
into potentially a broken line as they merge and coalesce with one
another. The primary concern for any severe storms today will be
damaging winds and heavy to torrential rainfall, with secondary
concerns for hail and potentially an isolated tornado.
Highs today are expected to reach the upper 80s in the north and the
low 90s in the south, despite any cloud cover as the WAA pipeline
remains at full blast until the fropa.
Tonight through Monday:
Once the well-advertised cold front pushes through (expected to be
through the forecast area by tonight), the storms will go with it,
leaving clearing skies and a dry forecast for the overnight period.
However, clouds will clutter the skies once more on Monday with a
chance for showers, especially in the Bluegrass region and locations
east of I-65. This is as the upper low spins down into the region,
which will also bring significantly cooler temperatures. Look for
lows to range from the lower 60s in the north to the upper 60s in
the southeast. Highs on Monday will range from the mid 70s in the
north to around the 80 degree mark in the south.
.LONG TERM (Monday Night through Saturday)...
Issued at 245 AM EDT Sun Jul 27 2014
An amplified pattern over the CONUS will persist this week with
troughing noted over the Midwest providing unseasonably cool
weather.
Tues-Thurs we`ll be dry with sfc high pressure in the area.
Tuesday`s highs will flirt with record cold highs which are in the
70s at climate stations. Forecast highs for Tuesday range from
73-79 across the area. We`ll then see a little bit of a warm-up
into the upper 70s and lower 80s for Wed/Thu. Night time lows will
be in the upper 50s and lower 60s.
By Friday, the pattern looks to attempt to become more a of a split
flow with an upper low attempting to be cut off over the Midwest.
As shortwaves increase in the trough and upper low toward the end of
the week, rain/storm chances will re-emerge with on and off
showers/storms possible through the weekend.
&&
.AVIATION (18Z TAF Update)...
Issued at 105 PM EDT Sun Jul 27 2014
Rather difficult TAF forecast unfolding this afternoon and evening,
as guidance is struggling to resolve convection across the
region. It appears the main focus for convection is just now
shifting south of KSDF, so will initiate with a dry forecast there.
Expect showers/storms to affect KLEX/KBWG this afternoon as the
atmosphere remains quite unstable. Some of these storms may be
severe, with locally damaging winds and large hail. Will leave just
VCTS wording given the expected scattered nature of the storms and
amend as necessary.
Otherwise, a cold front will sweep through all sites tonight,
allowing for much drier air to work into the region. All sites will
go VFR, with NNW winds around 10 knots.
&&
.LMK WATCHES/WARNINGS/ADVISORIES...
KY...NONE.
IN...NONE.
&&
$$
Mesoscale......KJD
Short Term.....lg
Long Term......AMS
Aviation.......KJD
AREA FORECAST DISCUSSION
NWS LOUISVILLE KY
1228 PM EDT Sun Jul 27 2014
...Mesoscale Forecast Update...
Issued at 1225 PM EDT Sun Jul 27 2014
Latest thinking continues to remain on track. Current severe
convection across east-central KY is likely still elevated in
nature, given surface temperatures only in the upper 60s and lower
70s. This convection will mainly pose a large hail (possibly golf
ball sized at times) and isolated damaging wind threat.
A rather volatile airmass is advecting into south-central KY,
however, as peaks of sunshine have broke out (Bowling Green at
91/72). The prefrontal trough will interact with this airmass later
this afternoon, which should be enough to weaken the cap and
intiaite scattered supercells, mainly across south-central KY. The
latest runs of the HRRR continues to support this thinking. These
supercells will be capable of large hail (potentially 2+ inches) and
damaging winds. There will also be an isolated tornado threat given
the low-level speed shear and the lingering outflow boundaries that
storms may be able to interact with.
.SHORT TERM (Now through Monday)...
Issued at 359 AM EDT Sun Jul 27 2014
...Severe weather threat continues this morning through much of
today...
Currently:
The MCS that rolled through the forecast area late Saturday night
has not stopped convection from re-firing in a line extending
currently from roughly Daviess County, IN southeastward through
Elizabethtown, KY. These storms have developed near theta-e
advecting in from the west, along with an increase of low-level
PWATs, per the CIMMS NearCast model. This cluster has all of the
features of being severe; however, latest available AMDAR soundings
show a shallow stable layer, which may help to keep the worst of the
winds aloft. Regardless, the concern is certainly there that despite
that these storms should be primarily elevated, they seem to be able
to overcome the layer and go surface-based. An additional concern
that was not present with the previous MCS is that a directional
shear component has been added to the increase in speed shear as the
low-level jet ramps up and surface southerly winds persist.
Today:
Continued uncertainty exists for the exact evolution of today`s
storms, although given how easily convection was able to develop
overnight and how quickly the local atmosphere was able to recover
behind the MCS, this is concerning given all of the other parameters
that will line up to create a severe threat for much of central KY
and south-central IN. The worked over atmosphere has not stopped
storm development. Models are showing 0-6km bulk shear today will be
increasing from approximately 30kts. in southern KY to 50kts. north
of the Ohio River to 40kts in the south to 60kts. in the north by
late today. SBCAPE, while some already exists this morning, will
increase to over 2500 J/kg under the sun today. The focus of where
storms will develop and how they`ll move will be a short-term,
mesoscale based forecasting approach as they ride leftover
boundaries and wherever the greater instability sets up, which
currently looks to be in southern and eastern KY. Hi-res models are
showing multiple rounds of storms but clearing out by late this
afternoon. Think this will be more dependent on the timing of the
front. The mode early on could be discrete supercells, congealing
into potentially a broken line as they merge and coalesce with one
another. The primary concern for any severe storms today will be
damaging winds and heavy to torrential rainfall, with secondary
concerns for hail and potentially an isolated tornado.
Highs today are expected to reach the upper 80s in the north and the
low 90s in the south, despite any cloud cover as the WAA pipeline
remains at full blast until the fropa.
Tonight through Monday:
Once the well-advertised cold front pushes through (expected to be
through the forecast area by tonight), the storms will go with it,
leaving clearing skies and a dry forecast for the overnight period.
However, clouds will clutter the skies once more on Monday with a
chance for showers, especially in the Bluegrass region and locations
east of I-65. This is as the upper low spins down into the region,
which will also bring significantly cooler temperatures. Look for
lows to range from the lower 60s in the north to the upper 60s in
the southeast. Highs on Monday will range from the mid 70s in the
north to around the 80 degree mark in the south.
.LONG TERM (Monday Night through Saturday)...
Issued at 245 AM EDT Sun Jul 27 2014
An amplified pattern over the CONUS will persist this week with
troughing noted over the Midwest providing unseasonably cool
weather.
Tues-Thurs we`ll be dry with sfc high pressure in the area.
Tuesday`s highs will flirt with record cold highs which are in the
70s at climate stations. Forecast highs for Tuesday range from
73-79 across the area. We`ll then see a little bit of a warm-up
into the upper 70s and lower 80s for Wed/Thu. Night time lows will
be in the upper 50s and lower 60s.
By Friday, the pattern looks to attempt to become more a of a split
flow with an upper low attempting to be cut off over the Midwest.
As shortwaves increase in the trough and upper low toward the end of
the week, rain/storm chances will re-emerge with on and off
showers/storms possible through the weekend.
&&
.AVIATION (12Z TAF Update)...
Issued at 651 AM EDT Sun Jul 27 2014
Difficult forecast for today as ongoing convection causes
uncertainty in how convection will evolve later today. A surface low
is progged over central IL and moving toward the NE. Aloft,
upper-level low pressure is rotating down from the NW as a deep
Canadian trough primes to take over the region.
Strong to severe thunderstorms will continue to threaten all three
terminals but given the uncertainty in timing, have not included
specifics other than VCTS (but even this is likely to change
throughout the day). Amendments will need to be made as storms
develop and threaten the terminals. The fropa is expected to have
cleared all three terminals sometime or shortly after 00Z Monday and
will take with it storm activity.
Winds will be a concern during the day as 15 to 20 knot
southwesterly gradient winds are expected with higher gusts. Winds
could be higher in or around any storms.
&&
.LMK WATCHES/WARNINGS/ADVISORIES...
KY...NONE.
IN...NONE.
&&
$$
Mesoscale......KJD
Short Term.....lg
Long Term......AMS
Aviation.......lg
AREA FORECAST DISCUSSION
NWS CARIBOU ME
616 PM EDT SUN JUL 27 2014
.SYNOPSIS...
WEAK LOW PRESSURE IS CROSSING THE AREA SUNDAY EVENING. A MORE
POTENT LOW PRESSURE SYSTEM WILL THEN CROSS THE AREA MONDAY AND
MONDAY EVENING. HIGH PRESSURE BUILDS IN FOR TUESDAY NIGHT AND
WEDNESDAY.
&&
.NEAR TERM /UNTIL 6 AM MONDAY MORNING/...
616 PM UPDATE...A SHORTWAVE LIFTING ACROSS THE AREA IS PRODUCING
AN AREA OF SHOWERS WITH A FEW EMBEDDED THUNDERSTORMS THAT WILL
MOSTLY EXIT EASTERN MAINE WITHIN THE NEXT FEW HOURS. THERE IS AN
AREA OF CLEARING UPSTREAM ACROSS SOUTHERN MAINE AND NH WHERE IT
HAS TURNED MORE UNSTABLE AND ADDITIONAL SHOWERS AND SOME STRONGER
STORMS HAVE FORMED. THIS ACTIVITY WILL WEAKEN THIS EVENING WITH
THE LOSS OF HEATING AND AS IT MOVES INTO AN AREA THAT HAS BEEN
WORKED OVER WITH LOTS OF CLOUDS AND SHOWERS FROM EARLIER IN THE
DAY. THE MAIN UPDATE WAS TO THE POPS THIS EVENING BASED ON THE
LATEST RADAR TRENDS. ONLY MINOR TWEAKS TO SOME OF THE OTHER HOURLY
GRIDS BASED ON THE 6 PM OBSERVATIONS.
PREVIOUS DISCUSSION...
2 SERIES OF RAINFALL EVENTS EXPECTED THIS TERM. THE FIRST WAVE OF
RAINFALL W/ISOLATED TSTMS WILL COME THROUGH THIS EVENING AS LOW
PRES MOVES ACROSS SOUTHERN QUEBEC W/A SFC BOUNDARY LIFTING
NORTHWARD. THE BEST INSTABILITY HAS SHIFTED BACK ACROSS THE
CENTRAL HIGHLANDS INTO NORTHERN AREAS. HEAVY RAINFALL STILL THE
MAIN THREAT W/THE TSTMS. THE HRRR AND THE NAM ARE DONG WELL W/THE
PLACEMENT OF THE RAINFALL AS EVIDENT FROM THE LATEST RADAR LOOPS
W/A LINE OF RAIN AND EMBEDDED TSTMS ACROSS WESTERN AND SOUTHWEST
MAINE. STEADIER RAINFALL WILL MOVE NE INTO NORTHERN AND EASTERN
AREAS BY THIS EVENING W/WESTERN AND SOUTHWESTERN AREAS SEEING
THINGS LETTING UP BY LATE EVENING. THE SHOWERS AND POSSIBLE TSTMS
WILL EXIT NORTHERN MAINE BY EARLY MONDAY MORNING. SOME CLEARING IS
EXPECTED ACROSS THE WESTERN AND INTERIOR DOWNEAST SECTIONS LATER
TONIGHT WHICH COULD LEAD TO SOME DENSE FOG AS A LIGHT SSE WIND AND
WET GROUND WILL BE A GOOD SETUP FOR THIS POTENTIAL. FURTHER NORTH,
CLOUDS AND LEFTOVER SHOWERS WILL LIMIT THE EXTENSIVENESS OF THE
FOG. THEREFORE, PER COLLABORATION W/GYX, ADDED AREAS OF FOG FOR
THE CENTRAL HIGHLANDS EASTWARD TO INCLUDE THE BANGOR-BAR HARBOR
REGIONS AS WELL AS LINCOLN AND DANFORTH. TEMPERATURES OVERNIGHT
WILL RUN INTO THE 60S.
FOR MONDAY, A BREAK IN THE RAINFALL W/SOME FOG AROUND IN THE
MORNING BUT MORE RAIN ON THE WAY AS LOW PRES LIFTS NORTHWARD.
THE MORE STEADIER RAINFALL WILL ARRIVE BY MIDDAY ACROSS THE
DOWNEAST AND COASTAL AREAS AND THEN LIFT ACROSS THE REST OF THE
CWA DURING THE DAY ON MONDAY. A DECENT SSE INFLOW W/SOME MID LEVEL
FORCING WILL LEAD TO SOME DECENT RAINFALL AMOUNTS ESPECIALLY IN
THE FAVORED AREAS OF THE CENTRAL HIGHLANDS AND MOUNT KATAHDIN
W/THAT SSE FLOW. THE 12Z RUNS OF THE ECMWF AND NAM BRING A GOOD
SWATH OF SOME HEAVIER RAINFALL FROM 18-00Z AS THE LOW LIFTS ACROSS
CENTRAL AND WESTERN AREAS. THE 12Z GFS IS SIMILAR BUT SPLITS THE
HEAVY RAIN INTO 2 AREAS W/ONE AREA ACROSS THE WEST AND ANOTHER
ONE ACROSS THE EASTERN SECTIONS. ATTM, WILL USE A CONSENSUS FOR
RAINFALL PLACEMENT AND QPF WHICH SHOWS 1.00-1.25" OF RAIN ACROSS
THE WESTERN AND PORTIONS OF THE CENTRAL HIGHLANDS. TEMPERATURES
WILL BE HELD DOWN FROM WHERE THEY WERE TODAY AVERAGING IN THE LOW
TO MID 70S AT BEST.
&&
.SHORT TERM /6 AM MONDAY MORNING THROUGH MONDAY NIGHT/...
FAIRLY POTENT MID AND LOW LEVEL LOW PRESSURE OVER WESTERN MAINE
MONDAY EVENING WILL MOVE NORTH AND OUT OF THE AREA LATER MONDAY
NIGHT. AS THIS OCCURS, EXPECT SHOWERS TO GRADUALLY TAPER OFF FROM
SOUTHWEST TO NORTHEAST. MODELS HAD BEEN HAVING SIGNIFICANT TIMING
ISSUES REGARDING THE SYSTEM`S EXIT, BUT HAVE COME INTO BETTER
AGREEMENT NOW, MEETING IN THE MIDDLE WITH THE NAM AND ECMWF
SPEEDING THINGS UP AND THE ECMWF SLOWING THINGS DOWN.
FOR TUESDAY, LOOK FOR COOLER, DRIER AIR WITH A DECENT SOUTHWEST
BREEZE. IT COULD STILL BE UNSTABLE ENOUGH FOR A FEW SHOWERS, AND
KEPT IN A SLIGHT CHANCE OF SHOWERS. SKIES CLEAR AND WINDS SLACKEN
FOR TUESDAY NIGHT AS HIGH PRESSURE BUILDS IN, AND LOOK FOR
SOMEWHAT CHILLY LOW TEMPERATURES. QUIET FOR WEDNESDAY WITH HIGH
PRESSURE OVERHEAD. CYCLONIC SOUTHWEST FLOW ALOFT DOES PERSIST,
WITH AN UPPER LOW SITTING OVER JAMES BAY, BUT JUST NOT MUCH
MOISTURE TO WORK WITH OVER US.
&&
.LONG TERM /TUESDAY THROUGH SUNDAY/...
A FULL LATITUDE UPPER TROUGH CENTERED OVER THE GREAT LAKES REGION
WILL DOMINATE THE WEATHER PATTERN ACROSS EASTERN CONUS INTO NEXT
WEEKEND. DESPITE A SOUTHWEST FLOW AHEAD OF THE TROUGH
AXIS...FORECAST MODELS INDICATE PLENTY OF DRY AIR ADVECTING INTO
NEW ENGLAND. ANY SHOWERS WHICH FALL WILL BE ON THE LIGHT
SIDE.
&&
.AVIATION /22Z SUNDAY THROUGH FRIDAY/...
NEAR TERM: IFR AT KBGR AND KBHB AND VLIFR POSSIBLE OVERNIGHT IN
AREAS OF FOG. MVFR TO VFR AT THE NORTHERN TERMINALS WILL LOWER TO
IFR OVERNIGHT IN LOW CLOUDS AND PATCHY FOG. VLIFR TO IFR MONDAY AT
THE DOWN EAST TERMINALS WITH CONDITIONS POSSIBLY IMPROVING TO LOW
END MVFR AT THE NORTHERN TERMINALS.
SHORT TERM: IFR MONDAY NIGHT WITH SHOWERS, TAPERING OFF FROM SW TO
NE LATE AT NIGHT. IMPROVING TO VFR TUESDAY MORNING, WITH VFR
PERSISTING INTO WEDNESDAY OUTSIDE OF SOME PATCHY VALLEY FOG EARLY
WEDNESDAY MORNING.
&&
.MARINE...
NEAR TERM: DECIDED TO GO W/A SCA FOR HAZARDOUS SEAS STARTING
MONDAY AFTERNOON AND RUNNING IT INTO TUESDAY. WAVE GUIDANCE STILL
RUNNING ABOUT A FOOT TOO HIGH. FOLLOWED THE MIDNIGHT CREW`S
ASSESSMENT OF BRINGING SEAS TO 6 FT LATER MONDAY W/WINDS
INCREASING TO 15 TO 20 KTS. CAN SEE WIND GUSTS POSSIBLY HITTING 25
KTS FOR A TIME LATER MONDAY AFTERNOON AS THE LLVL JET OF 35 KTS
SWINGS OVER THE REGION.
SHORT TERM: SOUTHWEST WINDS NEAR OR JUST BELOW SMALL CRAFT LEVELS,
AND SEAS AT SMALL CRAFT LEVELS MONDAY NIGHT WILL DIMINISH/SUBSIDE
DURING THE DAY TUESDAY. LIGHT WINDS AND SEAS TUESDAY NIGHT AND
WEDNESDAY.
&&
.CAR WATCHES/WARNINGS/ADVISORIES...
ME...NONE.
MARINE...SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS FROM 4 PM MONDAY TO 3
PM EDT TUESDAY FOR ANZ050>052.
&&
$$
NEAR TERM...CB/HEWITT
SHORT TERM...FOISY
LONG TERM...OKULSKI
AVIATION...CB/HEWITT/FOISY
MARINE...CB/HEWITT/FOISY
AREA FORECAST DISCUSSION
NWS CARIBOU ME
253 PM EDT SUN JUL 27 2014
.SYNOPSIS...
WEAK LOW PRESSURE IS CROSSING THE AREA SUNDAY EVENING. A MORE
POTENT LOW PRESSURE SYSTEM WILL THEN CROSS THE AREA MONDAY AND
MONDAY EVENING. HIGH PRESSURE BUILDS IN FOR TUESDAY NIGHT AND
WEDNESDAY.
&&
.NEAR TERM /THROUGH MONDAY/...
2 SERIES OF RAINFALL EVENTS EXPECTED THIS TERM.
THE FIRST WAVE OF RAINFALL W/ISOLATED TSTMS WILL COME THROUGH THIS
EVENING AS LOW PRES MOVES ACROSS SOUTHERN QUEBEC W/A SFC BOUNDARY
LIFTING NORTHWARD. THE BEST INSTABILITY HAS SHIFTED BACK ACROSS
THE CENTRAL HIGHLANDS INTO NORTHERN AREAS. HEAVY RAINFALL STILL
THE MAIN THREAT W/THE TSTMS. THE HRRR AND THE NAM ARE DONG WELL
W/THE PLACEMENT OF THE RAINFALL AS EVIDENT FROM THE LATEST RADAR
LOOPS W/A LINE OF RAIN AND EMBEDDED TSTMS ACROSS WESTERN AND
SOUTHWEST MAINE. STEADIER RAINFALL WILL MOVE NE INTO NORTHERN AND
EASTERN AREAS BY THIS EVENING W/WESTERN AND SOUTHWESTERN AREAS
SEEING THINGS LETTING UP BY LATE EVENING. THE SHOWERS AND POSSIBLE
TSTMS WILL EXIT NORTHERN MAINE BY EARLY MONDAY MORNING. SOME
CLEARING IS EXPECTED ACROSS THE WESTERN AND INTERIOR DOWNEAST
SECTIONS LATER TONIGHT WHICH COULD LEAD TO SOME DENSE FOG AS A
LIGHT SSE WIND AND WET GROUND WILL BE A GOOD SETUP FOR THIS
POTENTIAL. FURTHER NORTH, CLOUDS AND LEFTOVER SHOWERS WILL LIMIT
THE EXTENSIVENESS OF THE FOG. THEREFORE, PER COLLABORATION W/GYX,
ADDED AREAS OF FOG FOR THE CENTRAL HIGHLANDS EASTWARD TO INCLUDE
THE BANGOR-BAR HARBOR REGIONS AS WELL AS LINCOLN AND DANFORTH.
TEMPERATURES OVERNIGHT WILL RUN INTO THE 60S.
FOR MONDAY, A BREAK IN THE RAINFALL W/SOME FOG AROUND IN THE
MORNING BUT MORE RAIN ON THE WAY AS LOW PRES LIFTS NORTHWARD.
THE MORE STEADIER RAINFALL WILL ARRIVE BY MIDDAY ACROSS THE
DOWNEAST AND COASTAL AREAS AND THEN LIFT ACROSS THE REST OF THE
CWA DURING THE DAY ON MONDAY. A DECENT SSE INFLOW W/SOME MID LEVEL
FORCING WILL LEAD TO SOME DECENT RAINFALL AMOUNTS ESPECIALLY IN
THE FAVORED AREAS OF THE CENTRAL HIGHLANDS AND MOUNT KATAHDIN
W/THAT SSE FLOW. THE 12Z RUNS OF THE ECMWF AND NAM BRING A GOOD
SWATH OF SOME HEAVIER RAINFALL FROM 18-00Z AS THE LOW LIFTS ACROSS
CENTRAL AND WESTERN AREAS. THE 12Z GFS IS SIMILAR BUT SPLITS THE
HEAVY RAIN INTO 2 AREAS W/ONE AREA ACROSS THE WEST AND ANOTHER
ONE ACROSS THE EASTERN SECTIONS. ATTM, WILL USE A CONSENSUS FOR
RAINFALL PLACEMENT AND QPF WHICH SHOWS 1.00-1.25" OF RAIN ACROSS
THE WESTERN AND PORTIONS OF THE CENTRAL HIGHLANDS. TEMPERATURES
WILL BE HELD DOWN FROM WHERE THEY WERE TODAY AVERAGING IN THE LOW
TO MID 70S AT BEST.
&&
.SHORT TERM /MONDAY NIGHT THROUGH WEDNESDAY/...
FAIRLY POTENT MID AND LOW LEVEL LOW PRESSURE OVER WESTERN MAINE
MONDAY EVENING WILL MOVE NORTH AND OUT OF THE AREA LATER MONDAY
NIGHT. AS THIS OCCURS, EXPECT SHOWERS TO GRADUALLY TAPER OFF FROM
SOUTHWEST TO NORTHEAST. MODELS HAD BEEN HAVING SIGNIFICANT TIMING
ISSUES REGARDING THE SYSTEM`S EXIT, BUT HAVE COME INTO BETTER
AGREEMENT NOW, MEETING IN THE MIDDLE WITH THE NAM AND ECMWF
SPEEDING THINGS UP AND THE ECMWF SLOWING THINGS DOWN.
FOR TUESDAY, LOOK FOR COOLER, DRIER AIR WITH A DECENT SOUTHWEST
BREEZE. IT COULD STILL BE UNSTABLE ENOUGH FOR A FEW SHOWERS, AND
KEPT IN A SLIGHT CHANCE OF SHOWERS. SKIES CLEAR AND WINDS SLACKEN
FOR TUESDAY NIGHT AS HIGH PRESSURE BUILDS IN, AND LOOK FOR
SOMEWHAT CHILLY LOW TEMPERATURES. QUIET FOR WEDNESDAY WITH HIGH
PRESSURE OVERHEAD. CYCLONIC SOUTHWEST FLOW ALOFT DOES PERSIST,
WITH AN UPPER LOW SITTING OVER JAMES BAY, BUT JUST NOT MUCH
MOISTURE TO WORK WITH OVER US.
&&
.LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/...
A FULL LATITUDE UPPER TROUGH CENTERED OVER THE GREAT LAKES REGION
WILL DOMINATE THE WEATHER PATTERN ACROSS EASTERN CONUS INTO NEXT
WEEKEND. DESPITE A SOUTHWEST FLOW AHEAD OF THE TROUGH
AXIS...FORECAST MODELS INDICATE PLENTY OF DRY AIR ADVECTING INTO
NEW ENGLAND. ANY SHOWERS WHICH FALL WILL BE ON THE LIGHT
SIDE.
&&
.AVIATION /18Z SUNDAY THROUGH FRIDAY/...
NEAR TERM: VFR FOR THE NORTHERN TERMINALS TO START OUT THE CYCLE
W/SOME TSTMS INTO THE EVENING AND THEN CONDITIONS ARE FORECAST TO
DROP TO MVFR AND EVENTUALLY IFR BY EARLY MONDAY. ACROSS KBGR AND
KBHB, MVFR GOING TO IFR AND PERHAPS LIFR FOR A TIME EARLY MONDAY
MORNING AND THEN CONDITIONS GRADUALLY IMPROVING TO MVFR AS THE
LOW LIFTS NORTH MONDAY AFTERNOON.
SHORT TERM: IFR MONDAY NIGHT WITH SHOWERS, TAPERING OFF FROM SW TO
NE LATE AT NIGHT. IMPROVING TO VFR TUESDAY MORNING, WITH VFR
PERSISTING INTO WEDNESDAY OUTSIDE OF SOME PATCHY VALLEY FOG EARLY
WEDNESDAY MORNING.
&&
.MARINE...
NEAR TERM: DECIDED TO GO W/A SCA FOR HAZARDOUS SEAS STARTING
MONDAY AFTERNOON AND RUNNING IT INTO TUESDAY. WAVE GUIDANCE STILL
RUNNING ABOUT A FOOT TOO HIGH. FOLLOWED THE MIDNIGHT CREW`S
ASSESSMENT OF BRINGING SEAS TO 6 FT LATER MONDAY W/WINDS
INCREASING TO 15 TO 20 KTS. CAN SEE WIND GUSTS POSSIBLY HITTING 25
KTS FOR A TIME LATER MONDAY AFTERNOON AS THE LLVL JET OF 35 KTS
SWINGS OVER THE REGION.
SHORT TERM: SOUTHWEST WINDS NEAR OR JUST BELOW SMALL CRAFT LEVELS,
AND SEAS AT SMALL CRAFT LEVELS MONDAY NIGHT WILL DIMINISH/SUBSIDE
DURING THE DAY TUESDAY. LIGHT WINDS AND SEAS TUESDAY NIGHT AND
WEDNESDAY.
&&
.CAR WATCHES/WARNINGS/ADVISORIES...
ME...NONE.
MARINE...SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS FROM 4 PM MONDAY TO 3
PM EDT TUESDAY FOR ANZ050>052.
&&
$$
NEAR TERM...HEWITT
SHORT TERM...FOISY
LONG TERM...OKULSKI
AVIATION...HEWITT/FOISY
MARINE...HEWITT/FOISY
AREA FORECAST DISCUSSION
NWS WAKEFIELD VA
543 PM EDT SUN JUL 27 2014
.SYNOPSIS...
A STRONG COLD FRONT CROSSES THE AREA EARLY MONDAY...THEN STALLS
OFF THE MID ATLANTIC COAST MONDAY NIGHT. HIGH PRESSURE BUILDS
INTO THE AREA FROM THE NORTHWEST TUESDAY THROUGH THURSDAY.
&&
.NEAR TERM /UNTIL 6 AM MONDAY MORNING/...
DROPPED POPS TO HAVE A DRY FORECAST MOST AREAS THROUGH 00Z PER
LATEST CONDITIONS. MADE ONLY MINOR CHANGES TO THE FORECAST BEYOND
00Z.
PREV DISCUSSION... HRRR & NAM CONTINUE TO HAVE BEST HANDLE ON CRNT
CNDTNS SO HAVE LEANED TOWARD THEIR SOLNS. EXPECT ONLY SCT ACTIVITY
INTO THE ERLY EVE HRS. IT NOW LOOKS LIKE WE ARE LOOKING AT 2 AREAS
OF CONVECTION. FIRST IS THE S/W NOW MOVG INTO SRN W VA. THIS
PROGGED TO TRACK AN AREA OF SHWRS/TSTRMS ACROSS SOUTHERN HALF OF
FA (MAINLY SOUTH OF I64) THIS EVE AND INTO ERY MORN HRS. SCND AREA
OF CONVECTION (CRNTLY DVLPNG OVR OHIO) PROGGED TO TRACK EAST
ACROSS SRN PA/MD AFTR MIDNIGHT CLIPPING NORTHERN MOST COUNTIES OF
FA. GIVEN DIFFERENT MODEL SOLNS AND DECENT UPR JET SPRT...WILL
KEEP HIGH CHC TO LOW END LIKELY POPS (40-60%) ACROSS THE RGN. SVR
THREAT (HAIL/WIND/HVY RAIN) CONTS...BUT THREAT IS NOT AS HIGH AS
IT LOOKED EARLIER GIVEN THE CLOUD COVERAGE AND PCPN PAST 8 HRS.
LOWS IN THE U60S NW TO THE LWR-MID 70S SE.
&&
.SHORT TERM /6 AM MONDAY MORNING THROUGH WEDNESDAY/...
FRONT / LEADING TROF PROGGED TO MOVE OFF THE COAST MONDAY MORN...
TAKING MOST IF NOT ALL PCPN WITH IT. THIS ENDS ANY SVR THREAT ACROSS
THE AREA. GIVEN LINGERING UPR LVL NRGY & MSTR...KEPT LOW CHC POPS
EASTERN AREAS THROUGH THE MORNING HOURS THEN CONFINED SLGHT CHC POPS
TO IMMEDIATE COASTAL AREAS DRNG THE AFTRN. GIVEN INCREASING AMTS OF
AFTRN SUN & A DOWNSLOPING WEST WIND...TMPS XPCTD TO WARM INTO THE
U80S-L90S.
MODELS DVLP SCT CONVECTION ALONG THE STALLED FRNTL MON EVENING SO
HAVE CONFINED LOW CHC POPS TO COUNTIES BORDERING ALBEMARLE SND.
OTW...PT CLDY & COOLER. WEAK CAA SEEN AS WINDS BECOME NORTH. LOWS
IN THE 60S.
UPR LVL COOL POOL WILL COMBINE WITH DYTME HTNG AND LINGERING
TROFINESS OVR THE FA FOR ISLTD POPS TUE AFTRN. CAPPED POPS AT 20%
FOR NOW. PT SUNNY WITH BLO NRML TMPS. HIGHS IN THE L80S XCPT U70S
AT THE BEACHES. M CLR TO PT CLDY TUE NITE AND RTHR COMFY FOR LATE
JULY. LOWS M50S-M60S.
MSTLY SUNNY WITH BLO NRML TMPS WED AS HIGH PRS BUILDS OVR THE RGN.
HIGHS L-M80S.
&&
.LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/...
GOING WITH A COMBINATION OF THE 12Z GFS AND 12Z ECMWF FOR THE
EXTENDED PERIOD. LONGWAVE TROF OVR THE MID ATLC REGION WED NGT...WILL
RETROGRADE BACK INTO THE OH AND TN VALLEYS AND DEEPEN THU THRU SUN.
A FRONTAL BOUNDARY LINGERING OFF THE MID ATLC CST WED NGT INTO
FRI...WILL DRIFT BACK TWD THE CST LATE FRI THRU SUN. FOR NOW...WILL
MAINTAIN A DRY FCST FOR WED NGT INTO FRI...THEN INCREASE TO SLGT CHC
OR CHC POPS FOR FRI NGT THRU SUN. STILL FAIRLY COMFORTABLE WED NGT
AND THU...BEFORE A GRADUAL INCREASE IN HUMIDITY/LO LVL MOIST RETURNS
FOR FRI THRU SUN. MAX TEMPS WILL GENERALLY BE IN THE LWR TO MID
80S THRU THE PERIOD. MIN TEMPS WILL RANGE FM THE UPR 50S TO MID 60S
THU MORNG...IN THE LWR TO MID 60S FRI MORNG...RANGE THRU THE 60S SAT
MORNG...AND RANGE FM THE MID 60S TO LWR 70S SUN MORNG.
&&
.AVIATION /22Z SUNDAY THROUGH FRIDAY/...
CLOUD COVER WAS PUTTING A DAMPER ON CONVECTION TODAY. BREAKS IN THE
OVERCAST MAY HELP TO PRODUCE WIDELY SCT TSTMS LATER TODAY AND EARLY
THIS EVENING BUT CONFIDENCE TOO LOW TO INCLUDE. IN THE MEANTIME...AN
AREA OF LIGHT RAIN MOVING THROUGH HAMPTON ROADS/ECG AREA WILL MOVE
OFF THE COAST SHORTLY AFTER THE START OF THE 18Z TAF PERIOD.
INCLUDED A FEW OF SHOWERS OVERNIGHT AT ALL THE TAF SITES EXCEPT ECG.
THESE COULD BE ASSOCIATED WITH TSTMS. WEST WINDS DEVELOP IN THE
MORNING BEHIND A PREFRONTAL TROUGH AND UNDER THE INFLUENCE OF A
DEEPENING SURFACE LOW OVER NEW ENGLAND. THESE WINDS DRY OUT THE
ATMOSPHERE AND SHOULD END THE PCPN. THE FRONT ITSELF MOVES THROUGH
EARLY IN THE AFTN. AT THIS POINT AND APPEARS TO BE A DRY FRONTAL
PASSAGE.
NO IFR WAS PLACED IN THE TAFS. MVFR FOG IS PSBL AT SBY AND ECG PRIOR
TO THE W/SW WINDS.
OUTLOOK...MAINLY DRY WEATHER IS FORECAST DURING THE UPCOMING WORK
WEEK. SOME PATCHY MVFR/IFR FOG IS PSBL NEAR SUNRISE BUT WIDESPREAD
IFR IS NOT INDICATED AT THIS TIME.
&&
.MARINE...
NO HEADLINES IN THE SHORT TERM TNGT THRU TUE. A COLD FRONT
APPROACHES THE AREA FM THE NW THIS EVENG...THEN CROSSES THE WTRS AND
OFF THE CST MON INTO MON NGT. SSW WINDS 10 TO 15 KT THRU TNGT. WINDS
WILL TURN TO THE W DURING MON...THEN NW AND N MON NGT INTO TUE MRNG.
NNE WINDS 15 KT OR LESS EXPECTED TUE THRU WED. SE OR E WINDS 10 KT
OR LESS WED NGT THRU THU NGT...BEFORE BECOMING NE AGAIN ON FRI.
WAVES 1 TO 3 FT...AND SEAS 2 TO 4 FT.
&&
.AKQ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
NC...NONE.
VA...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...LKB/MPR
NEAR TERM...LKB/MPR
SHORT TERM...MPR
LONG TERM...TMG
AVIATION...LSA
MARINE...TMG
AREA FORECAST DISCUSSION
NWS WAKEFIELD VA
300 PM EDT SUN JUL 27 2014
.SYNOPSIS...
A STRONG COLD FRONT APPROACHES THE REGION FROM THE NORTHWEST THIS
AFTERNOON..THEN CROSSES THE AREA LATE TONIGHT AND MONDAY. HIGH
PRESSURE BUILDS INTO THE AREA FROM THE NORTHWEST TUESDAY THROUGH
THURSDAY.
&&
.NEAR TERM /UNTIL 6 AM MONDAY MORNING/...
STILL SOME UNCERTAINITIES WRT THE WX ACROSS THE AREA NEXT 6-12 HRS.
SO BASED THE FCST FOR NEXT SVRL HRS OFF OF CRNT RADAR/SFC TRENDS.
BAND OF SHWRS/TSTRMS MOVG EAST ACROSS SRN TIER VA AND NE NC CNTYS
WILL CONT TO MOVE EAST SO KEPT THE LIKELY POPS THERE. JUST SOME
SHWRS NOTED ACROSS THE REST OF THE FA ATTM. VSBY SAT LOOP SHOWING
PARTIAL THINNING OF THE CLOUDS ACROSS PIEDMONT AREAS. SHORT RANGE
MOS NUMBERS SHOW TMPS QUICKLY RISING INTO THE 80S IF ADDNTL HEATING
CAN OCCUR. SO LEFT HIGH TMPS ALONE FOR NOW (85-90).
WRT CONVECTION LATER TODAY...MAIN ACTION SHIFTS TO THE S/W ENERGY
OVR KY PROGGED TO DRIFT SE ACROSS THE AREA THIS EVE. CRNT TRAJECTORY
TRACKS MOST OF THE CONVECTION ALONG AND SOUTH OF I64. HOWEVER..STILL
EXPECT ADDNTL CONVECTION TO DVLP OVR THE MTS THEN MERGE WITH THE
ADVANCING S/W ENERGY. SVR PTNTL STILL EXISTS IF TMPS ARE ABLE TO
RISE TO FCST LEVELS. STAY TUNED.
PVS DSCN:
MADE SOME CHANGES TO GRIDS BASED ON LATEST RADAR TRENDS SFC OBS
AND MODEL GUIDANCE. MAIN CHANGE WAS TO ACCOUNT FOR LINE OF
CONVECTION MARCHING EAST ACROSS THE NC PIEDMONT ATTM. HRRR SEEMS
TO HAVE BEST HANDLE ON THE CRNT TRENDS...SO INCREASED POPS TO
LIKELY ACROSS SRN MOST COUNTIES NEXT SVRL HRS AS THIS LINE MOVES
EAST.. VSBY SAT LOOP SHOWING SOME PARTIAL SUNSHINE AHEAD OF IT TO
KEEP THE LINE GOING.
LOWERED TMPS BY A CATEGORY MOST PLACES (CLOSER TO LAV GUID) GIVEN
ALL THE CLOUDS AND PCPN FROM THE MORNING CONVECTIVE COMPLEX. TUFF
CALL FOR SERN COUNTIES AS TMPS MAY GET TO 90 THERE...BUT THEN DROP
IN ANY CONVECTION BY ERLY AFTRN.
MAIN QUESTION FOR THIS AFTRN IS HOW MUCH HEATING WILL OCCUR BEHIND
THE FIRST DEPARTING S/W AND AHEAD OF NXT APPRCHG S/W NOW OVR KY
VLLY. LATEST DATA SUGGESTS THIS COMPLEX TAKING A MORE SOUTHERLY
ROUTE (ACROSS SRN HALF OF VA / NC THIS EVENING.
SPC CONTINUES TO HAVE FA OUTLOOKED IN SLGHT RISK WITH A RECENTLY
ISSUED PWO FOR AREAS TO OUR WEST. STAY TUNED.
&&
.SHORT TERM /6 AM MONDAY MORNING THROUGH TUESDAY NIGHT/...
THE STRONG COLD FRONT QUICKLY PUSHES ACROSS THE REGION ON MONDAY.
OVERNIGHT SHOWERS/STORMS SHOULD BECOME MORE FOCUSED ALONG THE COLD
FRONT AND RE-FIRE IN INTENSITY DUE TO THE ADDED LIFT. OVERALL...
PRECIP SHOULD BE CONFINED TO COASTAL AREAS UNTIL THE FRONT CAN
PUSH WELL TO THE SOUTHEAST OF THE AREA BY LATE AFTN/EARLY EVENING.
ALTHOUGH THE OVERALL SEVERE WEATHER THREAT IS DIMINISHED ON
MONDAY...A FEW STORMS COULD BECOME SEVERE AND BE CAPABLE OF
PRODUCING STRONG WINDS...LARGE HAIL...AND LOCALLY HEAVY RAINFALL.
WEST WINDS WILL BE BREEZY WITH GUSTS TO AROUND 25 MPH AS A COOLER
AND DRIER CANADIAN AIRMASS FILTERS INTO THE REGION FROM THE NW-N.
WINDS AND SUNSHINE WILL BE KEY PLAYERS IN HIGH TEMPS ON MONDAY.
CURRENT FORECAST RANGES FROM THE UPPER 80S NW TO 90-95 SE.
BNDRY PROGGED TO STALL INVOF GULF STREAM MON NIGHT AND TUE WHILE A
COOLER AND DRIER AIRMASS FILTERS IN FROM THE NORTH. KEPT SLGHT CHC
POPS ALONG SERN CSTL AREAS MON EVENING. LOWS IN THE 60S...XCPT L70S
SERN CSTL AREAS. DRY TUESDAY ALONG WITH LOWER HUMIDITY AS DEWPOINTS
DROP INTO THE 50S. PARTLY TO MOSTLY SUNNY. HIGHS IN THE L80S...U70S AT
THE BEACHES. LOWS IN THE MID-UPPER 50S W TO MID 60S AT THE BEACHES.
&&
.LONG TERM /WEDNESDAY THROUGH SUNDAY/...
GOING WITH A COMBINATION OF THE 12Z GFS AND 12Z ECMWF FOR THE
EXTENDED PERIOD. LONGWAVE TROF DIGS OVR THE MID ATLC REGION TUE NGT
INTO EARLY THU...BEFORE RETROGRADING BACK INTO THE OH AND MS VALLEYS
THU AFTN THRU SAT. A FRONTAL BOUNDARY WILL LINGER OFF THE MID ATLC
CST TUE NGT THRU FRI...THEN DRIFTS BACK TWD THE CST FRI NGT THRU
SAT. WILL MAINTAIN A DRY FCST FOR TUE NGT THRU FRI...THEN HAVE ADDED
SLGT CHC POPS FOR FRI NGT AND SAT. A MORE COMFORTABLE AIRMASS WILL
DOMINATE THE AREA TUE NGT THRU THU...BEFORE A GRADUAL INCREASE IN
HUMIDITY RETURNS FOR FRI AND SAT. MAX TEMPS WILL GENERALLY BE IN THE
LWR TO MID 80S THRU THE PERIOD. MIN TEMPS WILL RANGE FM THE UPR 50S
TO MID 60S WED AND THU MORNGS...IN THE LWR TO MID 60S FRI
MORNG...AND RANGE THRU THE 60S SAT MORNG.
&&
.AVIATION /19Z SUNDAY THROUGH FRIDAY/...
CLOUD COVER WAS PUTTING A DAMPER ON CONVECTION TODAY. BREAKS IN THE
OVERCAST MAY HELP TO PRODUCE WIDELY SCT TSTMS LATER TODAY AND EARLY
THIS EVENING BUT CONFIDENCE TOO LOW TO INCLUDE. IN THE MEANTIME...AN
AREA OF LIGHT RAIN MOVING THROUGH HAMPTON ROADS/ECG AREA WILL MOVE
OFF THE COAST SHORTLY AFTER THE START OF THE 18Z TAF PERIOD.
INCLUDED A FEW OF SHOWERS OVERNIGHT AT ALL THE TAF SITES EXCEPT ECG.
THESE COULD BE ASSOCIATED WITH TSTMS. WEST WINDS DEVELOP IN THE
MORNING BEHIND A PREFRONTAL TROUGH AND UNDER THE INFLUENCE OF A
DEEPENING SURFACE LOW OVER NEW ENGLAND. THESE WINDS DRY OUT THE
ATMOSPHERE AND SHOULD END THE PCPN. THE FRONT ITSELF MOVES THROUGH
EARLY IN THE AFTN. AT THIS POINT AND APPEARS TO BE A DRY FRONTAL
PASSAGE.
NO IFR WAS PLACED IN THE TAFS. MVFR FOG IS PSBL AT SBY AND ECG PRIOR
TO THE W/SW WINDS.
OUTLOOK...MAINLY DRY WEATHER IS FORECAST DURING THE UPCOMING WORK
WEEK. SOME PATCHY MVFR/IFR FOG IS PSBL NEAR SUNRISE BUT WIDESPREAD
IFR IS NOT INDICATED AT THIS TIME.
&&
.MARINE...
NO HEADLINES XPCD THRU MON. A CDFNT PUSHES APPROACHES THE MID ATLC
REGION TDA...THEN MOVE ACRS THE WTRS AND OFF THE CST LATE TNGT
THROUGH MON NGT. SSW WINDS 10 TO 20 KT THROUGH TNGT. WINDS WILL TURN
TO THE W DURING MON...THEN NW AND N MON NGT INTO TUE MRNG.
WAVES/SEAS LIKELY TO RISE A FOOT OR TWO IN RESPONSE TO INCRSD SPDS
AND DIRECTION CHG TO NNW (MON NGT INTO TUE). GENERALLY NNE WINDS
15 KT OR LESS EXPECTED FOR TUE THRU THU.
&&
.AKQ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
NC...NONE.
VA...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...BMD
NEAR TERM...BMD/MPR
SHORT TERM...BMD
LONG TERM...TMG
AVIATION...LSA
MARINE...ALB
AREA FORECAST DISCUSSION
NWS WAKEFIELD VA
1201 PM EDT SUN JUL 27 2014
.SYNOPSIS...
A STRONG COLD FRONT APPROACHES THE REGION FROM THE NORTHWEST THIS
AFTERNOON..THEN CROSSES THE AREA LATE TONIGHT AND MONDAY. HIGH
PRESSURE BUILDS INTO THE AREA FROM THE NORTHWEST TUESDAY THROUGH
THURSDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
STILL SOME UNCERTAINITIES WRT THE WX ACROSS THE AREA NEXT 6-12 HRS.
SO BASED THE FCST FOR NEXT SVRL HRS OFF OF CRNT RADAR/SFC TRENDS.
BAND OF SHWRS/TSTRMS MOVG EAST ACROSS SRN TIER VA AND NE NC CNTYS
WILL CONT TO MOVE EAST SO KEPT THE LIKELY POPS THERE. JUST SOME
SHWRS NOTED ACROSS THE REST OF THE FA ATTM. VSBY SAT LOOP SHOWING
PARTIAL THINNING OF THE CLOUDS ACROSS PIEDMONT AREAS. SHORT RANGE
MOS NUMBERS SHOW TMPS QUICKLY RISING INTO THE 80S IF ADDNTL HEATING
CAN OCCUR. SO LEFT HIGH TMPS ALONE FOR NOW (85-90).
WRT CONVECTION LATER TODAY...MAIN ACTION SHIFTS TO THE S/W ENERGY
OVR KY PROGGED TO DRIFT SE ACROSS THE AREA THIS EVE. CRNT TRAJECTORY
TRACKS MOST OF THE CONVECTION ALONG AND SOUTH OF I64. HOWEVER..STILL
EXPECT ADDNTL CONVECTION TO DVLP OVR THE MTS THEN MERGE WITH THE
ADVANCING S/W ENERGY. SVR PTNTL STILL EXISTS IF TMPS ARE ABLE TO
RISE TO FCST LEVELS. STAY TUNED.
PVS DSCN:
MADE SOME CHANGES TO GRIDS BASED ON LATEST RADAR TRENDS SFC OBS
AND MODEL GUIDANCE. MAIN CHANGE WAS TO ACCOUNT FOR LINE OF
CONVECTION MARCHING EAST ACROSS THE NC PIEDMONT ATTM. HRRR SEEMS
TO HAVE BEST HANDLE ON THE CRNT TRENDS...SO INCREASED POPS TO
LIKELY ACROSS SRN MOST COUNTIES NEXT SVRL HRS AS THIS LINE MOVES
EAST.. VSBY SAT LOOP SHOWING SOME PARTIAL SUNSHINE AHEAD OF IT TO
KEEP THE LINE GOING.
LOWERED TMPS BY A CATEGORY MOST PLACES (CLOSER TO LAV GUID) GIVEN
ALL THE CLOUDS AND PCPN FROM THE MORNING CONVECTIVE COMPLEX. TUFF
CALL FOR SERN COUNTIES AS TMPS MAY GET TO 90 THERE...BUT THEN DROP
IN ANY CONVECTION BY ERLY AFTRN.
MAIN QUESTION FOR THIS AFTRN IS HOW MUCH HEATING WILL OCCUR BEHIND
THE FIRST DEPARTING S/W AND AHEAD OF NXT APPRCHG S/W NOW OVR KY
VLLY. LATEST DATA SUGGESTS THIS COMPLEX TAKING A MORE SOUTHERLY
ROUTE (ACROSS SRN HALF OF VA / NC THIS EVENING.
SPC CONTINUES TO HAVE FA OUTLOOKED IN SLGHT RISK WITH A RECENTLY
ISSUED PWO FOR AREAS TO OUR WEST. STAY TUNED.
&&
.SHORT TERM /MONDAY THROUGH TUESDAY NIGHT/...
THE STRONG COLD FRONT QUICKLY PUSHES ACROSS THE REGION ON MONDAY.
OVERNIGHT SHOWERS/STORMS SHOULD BECOME MORE FOCUSED ALONG THE COLD
FRONT AND RE-FIRE IN INTENSITY DUE TO THE ADDED LIFT. OVERALL...
PRECIP SHOULD BE CONFINED TO COASTAL AREAS UNTIL THE FRONT CAN
PUSH WELL TO THE SOUTHEAST OF THE AREA BY LATE AFTN/EARLY EVENING.
ALTHOUGH THE OVERALL SEVERE WEATHER THREAT IS DIMINISHED ON
MONDAY...A FEW STORMS COULD BECOME SEVERE AND BE CAPABLE OF
PRODUCING STRONG WINDS...LARGE HAIL...AND LOCALLY HEAVY RAINFALL.
WEST WINDS WILL BE BREEZY WITH GUSTS TO AROUND 25 MPH AS A COOLER
AND DRIER CANADIAN AIRMASS FILTERS INTO THE REGION FROM THE NW-N.
WINDS AND SUNSHINE WILL BE KEY PLAYERS IN HIGH TEMPS ON MONDAY.
CURRENT FORECAST RANGES FROM THE UPPER 80S NW TO 90-95 SE.
BNDRY PROGGED TO STALL INVOF GULF STREAM MON NIGHT AND TUE WHILE A
COOLER AND DRIER AIRMASS FILTERS IN FROM THE NORTH. KEPT SLGHT CHC
POPS ALONG SERN CSTL AREAS MON EVENING. LOWS IN THE 60S...XCPT L70S
SERN CSTL AREAS. DRY TUESDAY ALONG WITH LOWER HUMIDITY AS DEWPOINTS
DROP INTO THE 50S. PARTLY TO MOSTLY SUNNY. HIGHS IN THE L80S...U70S AT
THE BEACHES. LOWS IN THE MID-UPPER 50S W TO MID 60S AT THE BEACHES.
&&
.LONG TERM /WEDNESDAY THROUGH SATURDAY/...
GOING WITH A COMBINATION OF THE 12Z GFS AND 12Z ECMWF FOR THE
EXTENDED PERIOD. LONGWAVE TROF DIGS OVR THE MID ATLC REGION TUE NGT
INTO EARLY THU...BEFORE RETROGRADING BACK INTO THE OH AND MS VALLEYS
THU AFTN THRU SAT. A FRONTAL BOUNDARY WILL LINGER OFF THE MID ATLC
CST TUE NGT THRU FRI...THEN DRIFTS BACK TWD THE CST FRI NGT THRU
SAT. WILL MAINTAIN A DRY FCST FOR TUE NGT THRU FRI...THEN HAVE ADDED
SLGT CHC POPS FOR FRI NGT AND SAT. A MORE COMFORTABLE AIRMASS WILL
DOMINATE THE AREA TUE NGT THRU THU...BEFORE A GRADUAL INCREASE IN
HUMIDITY RETURNS FOR FRI AND SAT. MAX TEMPS WILL GENERALLY BE IN THE
LWR TO MID 80S THRU THE PERIOD. MIN TEMPS WILL RANGE FM THE UPR 50S
TO MID 60S WED AND THU MORNGS...IN THE LWR TO MID 60S FRI
MORNG...AND RANGE THRU THE 60S SAT MORNG.
&&
.AVIATION /16Z SUNDAY THROUGH THURSDAY/...
AREA OF CONVECTION SLIDING SE FM SW PA/NRN WV/NW VA TO CONT
TRACKING ESE THROUGH EARLY MRNG HRS W/ SOME WEAKENING AS IT DOES
SO. PTNTL FOR PCPN AND BRIEF MVFR CIGS/VSBYS...ESP KRIC-KSBY. A
SECOND AREA OF CONVECTION FCST TO EXIT THE MTNS MID/LT MRNG...AND
TRACK OVR THE RGN MIDDAY INTO THIS EVE (ALSO W/ PSBL BRIEF MVFR
CIGS/VSBYS/HVY RA). OTRW...SSW WINDS GUSTING TO 15 KT AND SCT-BKN
CLDS XPCD TDA AS A COLD FRONT APPROACHES THE REGION FROM THE W.
THE FRONT IS XPCD TO CROSS THE REGION ON MONDAY W/ LO PROB FOR
PCPN AND GUSTY MNLY W WNDS (TO 20 KT). MNLY VFR CONDS MON NGT INTO
WED.
NOTE: OBSERVATIONS FROM KSBY ARE NOT READILY AVAILABLE DUE TO A
COMMUNICATIONS PROBLEM. RETURN TO SERVICE IS UNKNOWN AT THIS TIME.
HOWEVER...CURRENT INFORMATION MAY BE OBTAINED BY CALLING INTO THE
ASOS SITE DIRECTLY. AMD NOT SKED WILL BE APPENDED TO THE KSBY TAF
UNTIL FURTHER NOTICE.
&&
.MARINE...
NO HEADLINES XPCD THRU MON. A CDFNT PUSHES APPROACHES THE MID ATLC
REGION TDA...THEN MOVE ACRS THE WTRS AND OFF THE CST LATE TNGT
THROUGH MON NGT. SSW WINDS 10 TO 20 KT THROUGH TNGT. WINDS WILL TURN
TO THE W DURING MON...THEN NW AND N MON NGT INTO TUE MRNG.
WAVES/SEAS LIKELY TO RISE A FOOT OR TWO IN RESPONSE TO INCRSD SPDS
AND DIRECTION CHG TO NNW (MON NGT INTO TUE). GENERALLY NNE WINDS
15 KT OR LESS EXPECTED FOR TUE THRU THU.
&&
.AKQ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
NC...NONE.
VA...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...MPR
NEAR TERM...MPR
SHORT TERM...BMD
LONG TERM...TMG
AVIATION...ALB
MARINE...ALB
AREA FORECAST DISCUSSION
NWS GRAND RAPIDS MI
256 PM EDT SUN JUL 27 2014
LATEST UPDATE...
MESOSCALE DISCUSSION
.MESOSCALE DISCUSSION...
ISSUED AT 251 PM EDT SUN JUL 27 2014
STORMS HAVE BECOME MORE ORGANIZED ACROSS THE AREA WITH THE
SYNOPTIC LIFT FROM THE APPROACHING WAVE MOVING IN. THE ATMOSPHERE
IS CHARACTERIZED WITH 2000 J/KG ML CAPE FOR MOST OF THE AREA. DEEP
LAYER SHEAR IS GREATER THAN 35 KNOTS. THE CAPE IS HIGH IN THE -10
TO -30 DEG C LAYER. THUS THE STORMS WILL CONTINUE TO STRENGTHEN
WITH LARGE HAIL THE PRIMARY THREAT. DAMAGING WINDS RISK EXISTS AS
WELL...AND AN ISOLATED TORNADO MAY OCCUR.
&&
.SYNOPSIS...
ISSUED AT 328 AM EDT SUN JUL 27 2014
THUNDERSTORMS ARE LIKELY TODAY ACROSS SOUTHWEST LOWER MICHIGAN. A
FEW OF THE STORMS COULD BE STRONG TO SEVERE...ESPECIALLY SOUTHEAST
OF GRAND RAPIDS. TEMPERATURES WILL BE QUITE A BIT COOLER MONDAY AND
STRUGGLE TO REACH 70...WELL BELOW NORMAL FOR LATE JULY. HIGHS MUCH
OF NEXT WEEK WILL BE IN THE 70S.
&&
.UPDATE...
ISSUED AT 1134 AM EDT SUN JUL 27 2014
NOT MAJOR CHANGES TO THE FORECAST. RISK FOR STRONG TO SEVERE
STORMS CONTINUES FOR THE AFTERNOON. WILL KEEP THE HIGHER POPS
GOING GIVEN THE CURRENT DESTABILIZATION AND APPROACHING MID LEVEL
WAVE.
UPDATE ISSUED AT 944 AM EDT SUN JUL 27 2014
DENSE FOG HAS LIFTED ALONG/SOUTH OF I-96 AND HAVE CANCELLED THE
DENSE FOG ADVISORY ISSUED EARLIER. HOWEVER HAVE LEFT THE ADVISORY
UP OVER THE LK MI NEARSHORE AREA FOR NOW AS WEB CAMS AT THE COAST
STILL REVEAL AREAS OF DENSE FOG.
EXTENSIVE STRATUS WILL INHIBIT DESTABILIZATION THIS MORNING BUT IT
SHOULD EVENTUALLY MIX OUT TOWARD NOON. LATEST RAP FCST SNDGS
STILL SHOWING 2000-3000 J/KG OF CAPE DEVELOPING BY 18Z WITH FAT
CAPE PROFILES. THE SIG HAIL PARAMETER FROM SPC MESO PAGE IS
ALREADY 1-1.5 WITH H7-H5 MID LEVEL LAPSE RATES AROUND 7C.
THEREFORE THE GREATEST THREAT AT LEAST INITIALLY EARLY THIS
AFTERNOON WITH DEVELOPING CONVECTION IS LARGE HAIL GREATER THAN
ONE INCH IN DIAMETER.
&&
.SHORT TERM...(TODAY THROUGH TUESDAY)
ISSUED AT 328 AM EDT SUN JUL 27 2014
FORECAST CONCERNS DEAL WITH THE CONVECTIVE THREAT TODAY.
OVERALL...OUR THINKING HASN`T CHANGED MUCH. HOWEVER...THE SPC SLIGHT
RISK HAS BEEN PUSHED SOUTH OUT OF THE CWA. THIS IS LIKELY DUE TO
SLIGHTLY LOWER SHEAR VALUES.
A COLD FRONT IS MOVING THROUGH NORTHWEST WISCONSIN ATTM. A FEW
SUPERCELLS DEVELOPED AND PRODUCED 2 INCH HAIL AS THEY MOVED THROUGH
CENTRAL WISCONSIN. THESE STORMS HAVE DIMINISHED THOUGH AS THEY`VE
OUTRUN THE STRONGER DYNAMICS.
WV IMAGERY SHOWS A WELL DEFINED SHORT WAVE MOVING OVER NORTHERN
MINNESOTA. THIS IS PUSHING THE FRONT SOUTHEAST TOWARD LOWER
MICHIGAN. AHEAD OF THE FRONT DEWPOINTS IN THE MID 60S WILL PROVIDE
PLENTY OF LOW LEVEL MOISTURE TO WORK WITH. LI`S AROUND -6C COUPLED
WITH MLCAPE VALUES AROUND 1500 J/KG WILL AND 0-6KM BULK SHEAR NEAR
40 KTS AND STRONG PVA SHOULD BE MORE THAN ENOUGH TO GENERATE SOME
ORGANIZED STORMS TODAY. FAVORED TIME FRAME IS FROM AROUND 11 AM
THROUGH 3-4 PM. FAVORED AREA IS SOUTHEAST OF GRAND RAPIDS. HIGH
LIKELY AND ABOVE POPS ARE IN THE GRIDS TODAY. CERTAINLY CAN`T RULE
OUT A SEVERE STORM OR TWO. HAIL IS THE MAIN THREAT WITH THE COLD
TEMPS ALOFT COMING IN.
THE COLD FRONT WILL QUICKLY SWEEP THROUGH THE CWA BY THIS EVENING
AND MUCH COOLER AND DRIER AIR WILL MOVE IN FOR MONDAY. HIGHS MOSTLY
IN THE UPPER 60S TO AROUND 70 EXPECTED.
A SECONDARY COLD FRONT WILL DROP SOUTH TUESDAY SO WE INCLUDED CHC
POPS FOR THAT. H5 TEMPS FALL 4C FROM MONDAY THROUGH TUESDAY. SO
LAPSE RATES STEEPEN QUITE A BIT. WOULD EXPECT SOME SMALL HAIL OUT
OF ANY STORMS THAT DEVELOP TUESDAY.
.LONG TERM...(TUESDAY NIGHT THROUGH SATURDAY)
ISSUED AT 328 AM EDT SUN JUL 27 2014
MODELS ARE STILL INDICATING AN UPPER LEVEL TROUGH OVER THE GREAT
LAKES REGION THROUGH THE BULK OF THE LONG TERM PERIOD. THE CORE OF
THE TROUGH WILL BE CENTERED OVER ONTARIO AND QUEBEC...BUT COOLER AIR
WILL SPILL INTO THE AREA. HIGH TEMPERATURES THROUGH THE PERIOD WILL
END UP BEING 5 TO 10 DEGREES BELOW NORMAL. ACTUAL HIGHS WILL RANGE
FROM THE MIDDLE TO UPPER 70S WEDNESDAY THROUGH SATURDAY.
IN TERMS OF SENSIBLE WEATHER...CONTINUED THE FORECAST THEME OF
DIURNAL SHOWERS AND A FEW STORMS. COLD AIR IN THE MID LEVELS
COMBINED WITH JULY SUNSHINE SHOULD RESULT IN AFTERNOON AND EVENING
POP UP SHOWERS AND STORMS. WEDNESDAY AND THURSDAY MAY HAVE A HIGHER
COVERAGE IN PRECIPITATION AS A MORE SUBSTANTIAL VORT LOBE IS
FORECAST TO SWING AROUND THE UPPER LOW...BRUSHING THE LOWER
PENINSULA.
CANNOT RULE OUT SOME SHOWERS AND A FEW STORMS EVEN INTO FRIDAY AND
SATURDAY AFTERNOON/S AS THE TROUGHING REMAINS IN PLACE. NOT A WASH
OUT IN THE LONG TERM BY ANY MEANS...BUT A FLARE UP IN COVERAGE EACH
DAY.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON)
ISSUED AT 103 PM EDT SUN JUL 27 2014
SCATTERED TSTMS ARE EXPECTED THROUGH 22-23Z WITH MAINLY MVFR CIGS.
IF/WHEN ANY STRONGER CELLS IMPACT A TERMINAL... LOOK FOR BRIEF IFR
CONDITIONS IN HEAVY RAIN. SOME HAIL AND GUSTY WINDS ARE ALSO
POSSIBLE. A FEW RAIN SHOWERS WILL LINGER THIS EVENING... FOLLOWED BY
LOWERING CIGS FROM NORTH TO SOUTH LATER THIS EVENING. WILL GO WITH
MVFR CIGS TONIGHT ALTHOUGH IFR CIGS CANNOT BE RULED OUT. ON MONDAY
THE CIGS SHOULD GRADUALLY LIFT TO VFR LEVELS BY NOON ALTHOUGH GUSTY
NORTH SFC WINDS TO 20 KNOTS ARE LIKELY.
&&
.MARINE...
ISSUED AT 1134 AM EDT SUN JUL 27 2014
WEBCAMS AND VISIBLE IMAGERY STILL SHOWED FAIRLY EXTENSIVE FOG ON
THE LAKESHORE. THE ADVISORY FOR FOG WAS STRETCHED INTO THE
AFTERNOON. THE WIND SHIFT AND DRY AIR ADVECTION LATER TODAY WILL
BREAK UP THE FOG.
HIGH POTENTIAL FOR BEACH HAZARDS AND SMALL CRAFT CONDITIONS LATER
TONIGHT INTO MONDAY.
&&
.HYDROLOGY...
ISSUED AT 1207 PM EDT SAT JUL 26 2014
THE MAIN PRECIPITATION THREAT WILL BE SUNDAY AS MOISTURE EDGES UP
INTO THE AREA. PWAT VALUES PUSH BETWEEN 1.0 TO 1.5 INCHES DURING
THE AFTERNOON. THIS MAY RESULT IN LOCALIZED HEAVY RAINFALL IN AND
AROUND THUNDERSTORMS. HOWEVER...AREA AVERAGES ARE MORE LIKELY TO
RANGE FROM ONE-QUARTER TO ONE-HALF AN INCH. PRECIPITATION THEN
SEEMS TO LINGER INTO MONDAY BUT SHOULD NOT BE OF ANY GREAT
SIGNIFICANCE IN THE MONDAY MORNING TIME FRAME.
ASIDE FROM SUNDAYS FOCUS...WE WILL SEE MAINLY DRY CONDITIONS TODAY.
ADDITIONAL CHANCES FOR LIGHT RAIN EXIST AS WE HEAD THROUGH THE NEW
WORK WEEK. NO HIGH END PRECIPITATION EVENTS ARE ANTICIPATED TO AFFECT
THE AREA. RIVERS CONTINUE TO RUN WELL BELOW ACTION STAGE...SO NO
CONCERN FOR RIVER FLOODING AT THIS TIME.
&&
.GRR WATCHES/WARNINGS/ADVISORIES...
MI...BEACH HAZARDS STATEMENT FROM MONDAY MORNING THROUGH MONDAY
EVENING FOR MIZ037-043-050-056-064-071.
LM...SMALL CRAFT ADVISORY FROM 8 PM THIS EVENING TO 6 AM EDT TUESDAY
FOR LMZ844>849.
&&
$$
MESOSCALE...MJS
UPDATE...MJS
SYNOPSIS...93
SHORT TERM...93
LONG TERM...DUKE
AVIATION...MEADE
HYDROLOGY...JAM
MARINE...MJS
AREA FORECAST DISCUSSION
NWS GRAND RAPIDS MI
106 PM EDT SUN JUL 27 2014
LATEST UPDATE...
AVIATION
.SYNOPSIS...
ISSUED AT 328 AM EDT SUN JUL 27 2014
THUNDERSTORMS ARE LIKELY TODAY ACROSS SOUTHWEST LOWER MICHIGAN. A
FEW OF THE STORMS COULD BE STRONG TO SEVERE...ESPECIALLY SOUTHEAST
OF GRAND RAPIDS. TEMPERATURES WILL BE QUITE A BIT COOLER MONDAY AND
STRUGGLE TO REACH 70...WELL BELOW NORMAL FOR LATE JULY. HIGHS MUCH
OF NEXT WEEK WILL BE IN THE 70S.
&&
.UPDATE...
ISSUED AT 1134 AM EDT SUN JUL 27 2014
NOT MAJOR CHANGES TO THE FORECAST. RISK FOR STRONG TO SEVERE
STORMS CONTINUES FOR THE AFTERNOON. WILL KEEP THE HIGHER POPS
GOING GIVEN THE CURRENT DESTABILIZATION AND APPROACHING MID LEVEL
WAVE.
UPDATE ISSUED AT 944 AM EDT SUN JUL 27 2014
DENSE FOG HAS LIFTED ALONG/SOUTH OF I-96 AND HAVE CANCELLED THE
DENSE FOG ADVISORY ISSUED EARLIER. HOWEVER HAVE LEFT THE ADVISORY
UP OVER THE LK MI NEARSHORE AREA FOR NOW AS WEB CAMS AT THE COAST
STILL REVEAL AREAS OF DENSE FOG.
EXTENSIVE STRATUS WILL INHIBIT DESTABILIZATION THIS MORNING BUT IT
SHOULD EVENTUALLY MIX OUT TOWARD NOON. LATEST RAP FCST SNDGS
STILL SHOWING 2000-3000 J/KG OF CAPE DEVELOPING BY 18Z WITH FAT
CAPE PROFILES. THE SIG HAIL PARAMETER FROM SPC MESO PAGE IS
ALREADY 1-1.5 WITH H7-H5 MID LEVEL LAPSE RATES AROUND 7C.
THEREFORE THE GREATEST THREAT AT LEAST INITIALLY EARLY THIS
AFTERNOON WITH DEVELOPING CONVECTION IS LARGE HAIL GREATER THAN
ONE INCH IN DIAMETER.
&&
.SHORT TERM...(TODAY THROUGH TUESDAY)
ISSUED AT 328 AM EDT SUN JUL 27 2014
FORECAST CONCERNS DEAL WITH THE CONVECTIVE THREAT TODAY.
OVERALL...OUR THINKING HASN`T CHANGED MUCH. HOWEVER...THE SPC SLIGHT
RISK HAS BEEN PUSHED SOUTH OUT OF THE CWA. THIS IS LIKELY DUE TO
SLIGHTLY LOWER SHEAR VALUES.
A COLD FRONT IS MOVING THROUGH NORTHWEST WISCONSIN ATTM. A FEW
SUPERCELLS DEVELOPED AND PRODUCED 2 INCH HAIL AS THEY MOVED THROUGH
CENTRAL WISCONSIN. THESE STORMS HAVE DIMINISHED THOUGH AS THEY`VE
OUTRUN THE STRONGER DYNAMICS.
WV IMAGERY SHOWS A WELL DEFINED SHORT WAVE MOVING OVER NORTHERN
MINNESOTA. THIS IS PUSHING THE FRONT SOUTHEAST TOWARD LOWER
MICHIGAN. AHEAD OF THE FRONT DEWPOINTS IN THE MID 60S WILL PROVIDE
PLENTY OF LOW LEVEL MOISTURE TO WORK WITH. LI`S AROUND -6C COUPLED
WITH MLCAPE VALUES AROUND 1500 J/KG WILL AND 0-6KM BULK SHEAR NEAR
40 KTS AND STRONG PVA SHOULD BE MORE THAN ENOUGH TO GENERATE SOME
ORGANIZED STORMS TODAY. FAVORED TIME FRAME IS FROM AROUND 11 AM
THROUGH 3-4 PM. FAVORED AREA IS SOUTHEAST OF GRAND RAPIDS. HIGH
LIKELY AND ABOVE POPS ARE IN THE GRIDS TODAY. CERTAINLY CAN`T RULE
OUT A SEVERE STORM OR TWO. HAIL IS THE MAIN THREAT WITH THE COLD
TEMPS ALOFT COMING IN.
THE COLD FRONT WILL QUICKLY SWEEP THROUGH THE CWA BY THIS EVENING
AND MUCH COOLER AND DRIER AIR WILL MOVE IN FOR MONDAY. HIGHS MOSTLY
IN THE UPPER 60S TO AROUND 70 EXPECTED.
A SECONDARY COLD FRONT WILL DROP SOUTH TUESDAY SO WE INCLUDED CHC
POPS FOR THAT. H5 TEMPS FALL 4C FROM MONDAY THROUGH TUESDAY. SO
LAPSE RATES STEEPEN QUITE A BIT. WOULD EXPECT SOME SMALL HAIL OUT
OF ANY STORMS THAT DEVELOP TUESDAY.
.LONG TERM...(TUESDAY NIGHT THROUGH SATURDAY)
ISSUED AT 328 AM EDT SUN JUL 27 2014
MODELS ARE STILL INDICATING AN UPPER LEVEL TROUGH OVER THE GREAT
LAKES REGION THROUGH THE BULK OF THE LONG TERM PERIOD. THE CORE OF
THE TROUGH WILL BE CENTERED OVER ONTARIO AND QUEBEC...BUT COOLER AIR
WILL SPILL INTO THE AREA. HIGH TEMPERATURES THROUGH THE PERIOD WILL
END UP BEING 5 TO 10 DEGREES BELOW NORMAL. ACTUAL HIGHS WILL RANGE
FROM THE MIDDLE TO UPPER 70S WEDNESDAY THROUGH SATURDAY.
IN TERMS OF SENSIBLE WEATHER...CONTINUED THE FORECAST THEME OF
DIURNAL SHOWERS AND A FEW STORMS. COLD AIR IN THE MID LEVELS
COMBINED WITH JULY SUNSHINE SHOULD RESULT IN AFTERNOON AND EVENING
POP UP SHOWERS AND STORMS. WEDNESDAY AND THURSDAY MAY HAVE A HIGHER
COVERAGE IN PRECIPITATION AS A MORE SUBSTANTIAL VORT LOBE IS
FORECAST TO SWING AROUND THE UPPER LOW...BRUSHING THE LOWER
PENINSULA.
CANNOT RULE OUT SOME SHOWERS AND A FEW STORMS EVEN INTO FRIDAY AND
SATURDAY AFTERNOON/S AS THE TROUGHING REMAINS IN PLACE. NOT A WASH
OUT IN THE LONG TERM BY ANY MEANS...BUT A FLARE UP IN COVERAGE EACH
DAY.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON)
ISSUED AT 103 PM EDT SUN JUL 27 2014
SCATTERED TSTMS ARE EXPECTED THROUGH 22-23Z WITH MAINLY MVFR CIGS.
IF/WHEN ANY STRONGER CELLS IMPACT A TERMINAL... LOOK FOR BRIEF IFR
CONDITIONS IN HEAVY RAIN. SOME HAIL AND GUSTY WINDS ARE ALSO
POSSIBLE. A FEW RAIN SHOWERS WILL LINGER THIS EVENING... FOLLOWED BY
LOWERING CIGS FROM NORTH TO SOUTH LATER THIS EVENING. WILL GO WITH
MVFR CIGS TONIGHT ALTHOUGH IFR CIGS CANNOT BE RULED OUT. ON MONDAY
THE CIGS SHOULD GRADUALLY LIFT TO VFR LEVELS BY NOON ALTHOUGH GUSTY
NORTH SFC WINDS TO 20 KNOTS ARE LIKELY.
&&
.MARINE...
ISSUED AT 1134 AM EDT SUN JUL 27 2014
WEBCAMS AND VISIBILE IMAGERY STILL SHOWED FAIRLY EXTENSIVE FOG ON
THE LAKESHORE. THE ADVISORY FOR FOG WAS STRETCHED INTO THE
AFTERNOON. THE WIND SHIFT AND DRY AIR ADVECTION LATER TODAY WILL
BREAK UP THE FOG.
HIGH POTENTIAL FOR BEACH HAZARDS AND SMALL CRAFT CONDITIONS LATER
TONIGHT INTO MONDAY.
&&
.HYDROLOGY...
ISSUED AT 1207 PM EDT SAT JUL 26 2014
THE MAIN PRECIPITATION THREAT WILL BE SUNDAY AS MOISTURE EDGES UP
INTO THE AREA. PWAT VALUES PUSH BETWEEN 1.0 TO 1.5 INCHES DURING
THE AFTERNOON. THIS MAY RESULT IN LOCALIZED HEAVY RAINFALL IN AND
AROUND THUNDERSTORMS. HOWEVER...AREA AVERAGES ARE MORE LIKELY TO
RANGE FROM ONE-QUARTER TO ONE-HALF AN INCH. PRECIPITATION THEN
SEEMS TO LINGER INTO MONDAY BUT SHOULD NOT BE OF ANY GREAT
SIGNIFICANCE IN THE MONDAY MORNING TIME FRAME.
ASIDE FROM SUNDAYS FOCUS...WE WILL SEE MAINLY DRY CONDITIONS TODAY.
ADDITIONAL CHANCES FOR LIGHT RAIN EXIST AS WE HEAD THROUGH THE NEW
WORK WEEK. NO HIGH END PRECIPITATION EVENTS ARE ANTICIPATED TO AFFECT
THE AREA. RIVERS CONTINUE TO RUN WELL BELOW ACTION STAGE...SO NO
CONCERN FOR RIVER FLOODING AT THIS TIME.
&&
.GRR WATCHES/WARNINGS/ADVISORIES...
MI...BEACH HAZARDS STATEMENT FROM MONDAY MORNING THROUGH MONDAY
EVENING FOR MIZ037-043-050-056-064-071.
LM...SMALL CRAFT ADVISORY FROM 8 PM THIS EVENING TO 6 AM EDT TUESDAY
FOR LMZ844>849.
DENSE FOG ADVISORY UNTIL 2 PM EDT THIS AFTERNOON FOR LMZ844>847.
&&
$$
UPDATE...MJS
SYNOPSIS...93
SHORT TERM...93
LONG TERM...DUKE
AVIATION...MEADE
HYDROLOGY...JAM
MARINE...MJS
AREA FORECAST DISCUSSION
NWS BUFFALO NY
347 PM EDT SUN JUL 27 2014
.SYNOPSIS...
LOW PRESSURE ACROSS EASTERN MICHIGAN WILL PIVOT AROUND AN UPPER
LEVEL DISTURBANCE...REACHING EASTERN NEW YORK STATE MONDAY MORNING. THIS
WILL BRING HEAVY RAINS TO PORTIONS OF WESTERN NEW YORK...WITH SOME
EMBEDDED THUNDERSTORMS. RAIN WILL LAST INTO MONDAY AND THEN A COOLER
PATTERN WILL SET UP FOR THE FIRST HALF OF THE WORK WEEK.
&&
.NEAR TERM /THROUGH MONDAY/...
THE REMAINDER THE AFTERNOON SHOULD LARGELY BE DRY...WITH VISIBLE
SATELLITE SHOWING A SIGNIFICANT DRY SLOT ACROSS CENTRAL NEW YORK
WHICH IS ROUGHLY ALIGNED WITH WEAK MID-LEVEL RIDGING. A FEW SHOWERS
AND THUNDERSTORMS WILL CLIP THE SAINT LAWRENCE VALLEY...WITH SOME
LIGHT SHOWERS OR SPRINKLES POSSIBLE IN THE SOUTHERN TIER...BUT THE
VAST MAJORITY OF THE REGION SHOULD BE DRY WITH A FAIR AMOUNT OF
SUNSHINE THROUGH 700 PM. TEMPERATURES WILL BE IN THE UPPER 70S TO
LOWER 80S WITH THE COOLER TEMPERATURES ALONG THE LAKESHORES AND
ACROSS HIGHER TERRAIN.
CONDITIONS WILL DETERIORATE RAPIDLY THIS EVENING...AS STEADIER
RAINS MOVE INTO THE REGION FROM THE OHIO VALLEY. THERE CONTINUES
TO BE A POTENTIAL FOR FLOODING...WITH MOST MESOSCALE 12Z GUIDANCE
CONTINUING TO FORECAST LOCALIZED RAINFALL AMOUNTS OF 2 TO 3
INCHES. THE FORECAST CHALLENGE IS DETERMINING EXACTLY WHEN AND
WHERE THESE AMOUNTS WILL FALL...GIVEN THE CONVECTIVE ELEMENTS OF
AN OTHERWISE SYNOPTIC EVENT.
AN ANOMALOUSLY DEEP 500 MB TROUGH ACROSS THE CENTRAL GREAT LAKES
THIS AFTERNOON WILL PIVOT ACROSS THE LOWER LAKES...WITH THIS
FORECAST TO STRENGTHEN A SURFACE LOW WHICH WILL TAKE ROUGHLY A
SIMILAR TRACK. THE UPPER LEVEL TROUGHING AND DIFFLUENCE WILL ALIGN
WITH DEEP LOW LEVEL MOISTURE TO PRODUCE LARGE SCALE LIFT ACROSS OUR
REGION TONIGHT INTO MONDAY. ON TOP OF THIS...SUBTLE LOW AND MID
LEVEL BOUNDARIES WILL FOCUS RAINFALL...AND IT WILL BE THESE
MESOSCALE FEATURES WHICH COULD PUSH RAINFALL AMOUNTS OVER THE 2 INCH
THRESHOLD. 12Z RUNS OF THE NAM/RGEM HAVE SHIFTED SOUTHEAST WITH THE
HEAVIEST RAINFALL FROM PREVIOUS RUNS...WHILE THE GFS SEEMS TOO DEEP
WITH THE SURFACE LOW. 09Z SREF ENSEMBLES REFLECT 00/06Z GUIDANCE AND
PUT THE BULLS-EYE ACROSS THE NIAGARA FRONTIER...WITH THE LATEST RUNS
OF THE HRRR TENDING TO SUPPORT THESE SOLUTIONS. BASED ON THIS...HAVE
HIGH CONFIDENCE THAT THERE WILL BE HEAVY RAIN...BUT DO NOT HAVE HIGH
CONFIDENCE ON EXACTLY WHERE IT WILL BE...SINCE IT IS ONLY LIKELY TO
IMPACT A PORTION OF THE REGION. THE FORECAST FOLLOWS A CONSENSUS OF
ALL GUIDANCE...WHICH SUPPORTS THE CURRENT LOCATION OF THE FLOOD
WATCH. THE AREA MOST VULNERABLE IS URBAN AREAS AND THE BUFFALO
CREEKS...WHICH WOULD PROBABLY REACH FLOOD STAGE IF RAINFALL
TOTALS TOP 2 INCHES. LARGER BASINS ARE LESS LIKELY TO FLOOD...SINCE
THE AXIS OF HEAVY RAIN IS LIKELY TO BE TOO SMALL TO FILL A LARGER
BASIN SUCH AS THE GENESEE RIVER. ALSO...MOST RIVERS AND CREEKS ARE
AT FAIRLY LOW FLOWS TO START WITH.
EXPECT STEADY RAIN WITH EMBEDDED THUNDERSTORMS TO REACH WESTERN
PORTIONS OF THE SOUTHERN TIER AROUND SUNSET...THEN SLOWLY SPREAD
NORTHEAST TO BUFFALO LATE THIS EVENING AND ROCHESTER AROUND
MIDNIGHT. THERE IS A LIMITED SEVERE WEATHER POTENTIAL THIS
EVENING...HOWEVER WINDS ALOFT ARE FAIRLY LIGHT...AND NOT TERRIBLY
FAVORABLE FOR SEVERE WEATHER THOUGH A FEW STRONG STORMS CANNOT BE
RULED OUT. LATER TONIGHT...INSTABILITY WILL BECOME ELEVATED AS A
NORTHERLY SURFACE FLOW BECOMES ESTABLISHED.
THE AXIS OF HEAVY RAIN WILL SHIFT EASTWARD LATE TONIGHT INTO MONDAY
MORNING. MEANWHILE...MODERATE NORTHERLY FLOW WILL BE IN PLACE...WITH
GUSTS TO 25 MPH. THIS UPSLOPE COMPONENT COMBINED WITH COOLER
TEMPERATURES ALOFT AND UPPER LEVEL TROUGHING WILL CAUSE CLOUDS AND
POSSIBLY SHOWERS TO LINGER FOR MUCH OF THE DAY. COOLER AIR AND
CLOUDS KEEP TEMPERATURES IN THE 60S ON MONDAY...WHICH IS
UNSEASONABLY COOL FOR THIS TIME OF YEAR.
&&
.SHORT TERM /MONDAY NIGHT THROUGH WEDNESDAY NIGHT/...
COOL AIR WILL REMAIN ACROSS THE EASTERN GREAT LAKES ON MONDAY
NIGHT...BUT THE DRIER AIR ALOFT AND SUBSIDENCE WILL SUPPRESS ANY
LAKE EFFECT RESPONSE OTHER THAN A THIN LAYER OF LAKE INDUCED
STRATOCU TO THE SOUTHEAST OF LAKES ERIE AND ONTARIO. EXPECT A COOL
AND DRY NIGHT WITH LOWS IN THE MID 40S TO NEAR 50 ACROSS THE
INTERIOR OF THE SOUTHERN TIER AND THE TUG HILL PLATEAU...TO THE MID
TO UPPER 50S ALONG THE SHORES OF LAKES ERIE AND ONTARIO.
IT WILL BE A LITTLE WARMER ON TUESDAY WITH HIGHS N THE MID/UPR 60S
INLAND TO THE LOWER 70S ALONG THE LAKESHORES AND LOWER TERRAIN.
HOWEVER...THE WARMER SURFACE TEMPS COINCIDE WITH A COOLING ALOFT TO
AROUND +5C AT 850MB AS THE AXIS OF THE PERSISTENT CANADIAN TROUGH CROSSES
THE REGION. THIS WILL YIELD THE CHANCE OF DAYTIME SHOWERS ON TUESDAY
WITH SOME NIGHTTIME LAKE EFFECT RAIN TUESDAY NIGHT...AND EVEN THE
ISOLATED RISK OF WATERSPOUTS.
THE LOW CHANCE OF DIURNAL CYCLE SHOWERS CONTINUES ON WEDNESDAY AS
THE UPPER TROUGH ROTATES ANOTHER SPOKE OF VORTICITY ACROSS THE
REGION. THE HIGH TEMPS WILL BUMP UP ANOTHER NOTCH...TO THE UPPER 60S
TO MID 70S...SO WILL BRING BACK A CHANCE OF THUNDERSTORMS DURING
WEDNESDAY AFTERNOON. THE 850MB TEMPS WARM SUFFICIENTLY TO EXCLUDE
THE RISK OF WATERSPOUTS. WEDNESDAY NIGHT WILL BE LESS COOL WITH
OVERNIGHT LOWS IN THE 50S ACROSS THE REGION...AND A LOW CHANCE OF AN
OVERNIGHT SHOWER AS WELL.
&&
.LONG TERM /THURSDAY THROUGH SUNDAY/...
THE DEEP LONGWAVE TROUGH OVER THE GREAT LAKES AND NORTHEASTERN STATE
DURING MIDWEEK WILL SLOWLY DE-AMPLIFY AND RETREAT INTO QUEBEC BY THE
END OF THE WEEK. THE LOW CHANCE OF SHOWERS ON THURSDAY WILL GIVE WAY
TO NIL POPS ON THU NIGHT AND FRIDAY. HIGH TEMPS WILL RISE FROM MID
70S THURSDAY TO THE UPPER 70S ON FRIDAY.
THE SLOW WARMING TREND WILL CONTINUE ON SATURDAY...BUT A CLOSED LOW
DEVELOPING OVER THE OHIO VALLEY MAY FORCE ATLANTIC MOISTURE TO
SPREAD NORTH INTO OUR REGION WITH A CHANCE OF SHOWERS AND A FEW
THUNDERSTORMS SATURDAY AND SUNDAY AFTERNOONS.
&&
.AVIATION /20Z SUNDAY THROUGH FRIDAY/...
WEAK UPPER LEVEL RIDGING SHOULD KEEP CONDITIONS VFR FOR THE
REMAINDER OF THE AFTERNOON.
LOW PRESSURE WILL APPROACH THE REGION TONIGHT...WHICH WILL BRING
STEADY AND SOMETIMES HEAVY RAINFALL TO THE REGION TONIGHT. EXPECT
CIGS/VSBY TO GRADUALLY LOWER TO MVFR THIS EVENING FROM SW- NE AS
THIS LOW APPROACHES THE REGION. THE STRENGTHENING LOW WILL SET UP
A NE FLOW...WHICH IS LIKELY TO BRING EVEN LOWER CONDITIONS LATE
TONIGHT...WITH IFR OR LOWER CIGS A GOOD POSSIBLY. CIGS WILL BE
SLOW TO LIFT ON MONDAY MORNING...WITH A NORTHERLY UPSLOPE FLOW
AND LINGERING MOISTURE.
OUTLOOK...
MONDAY AFTERNOON...GRADUAL IMPROVEMENT FROM IFR/MVFR LATE
AFTERNOON AND EVENING.
TUESDAY THROUGH THURSDAY...MAINLY VFR WITH A CHANCE OF SHOWERS.
FRIDAY...VFR.
&&
.MARINE...
LOW PRESSURE WILL PIVOT SOUTH OF THE REGION TONIGHT AND THEN WILL
STRENGTHEN ACROSS EASTERN NEW YORK ON MONDAY. THIS WILL TIGHTEN THE
PRESSURE GRADIENT AND ESTABLISH A MODERATE NORTHERLY FLOW LATE
TONIGHT AND MONDAY. THE 12Z GFS APPEARS OVERDONE...BUT EVEN SO THE
NAM/RGEM ARE STRONGER THAN PREVIOUS RUNS AND SUPPORTS SMALL CRAFT
HEADLINES FOR LAKE ONTARIO...AND THE LOWER NIAGARA RIVER. EVEN LAKE
ERIE BEARS WATCHING...WITH WINDS/WAVES LIKELY TO APPROACH SMALL
CRAFT CRITERIA LATE TONIGHT AND MONDAY MORNING. WINDS WILL DIMINISH
MONDAY NIGHT...WITH A WEAKER FLOW FORECAST FOR MID-WEEK. COOLER
TEMPERATURES ALOFT SUGGEST THERE IS A CHANCE FOR WATERSPOUTS ON
TUESDAY NIGHT INTO WEDNESDAY.
&&
.BUF WATCHES/WARNINGS/ADVISORIES...
NY...FLOOD WATCH FROM 10 PM EDT THIS EVENING THROUGH MONDAY
AFTERNOON FOR NYZ001>004-010>014-019>021-085.
MARINE...SMALL CRAFT ADVISORY FROM 5 AM TO 2 PM EDT MONDAY FOR LOZ030.
SMALL CRAFT ADVISORY FROM 2 AM TO 8 PM EDT MONDAY FOR
LOZ042>044.
SMALL CRAFT ADVISORY FROM 5 AM TO 6 PM EDT MONDAY FOR
LOZ045.
&&
$$
SYNOPSIS...APFFEL
NEAR TERM...APFFEL
SHORT TERM...WCH
LONG TERM...WCH
AVIATION...APFFEL
MARINE...APFFEL
AREA FORECAST DISCUSSION
NWS BUFFALO NY
230 PM EDT SUN JUL 27 2014
.SYNOPSIS...
THIS AFTERNOON SHOULD BE MAINLY DRY...HOWEVER CONDITIONS WILL
DETERIORATE RAPIDLY THIS EVENING AS LOW PRESSURE PIVOTS FROM
EASTERN MICHIGAN TO NEW YORK STATE. THIS WILL BRING HEAVY RAINS TO
PORTIONS OF WESTERN NEW YORK...WITH EMBEDDED THUNDERSTORMS. THIS
WILL LAST INTO MONDAY BEFORE A COOLER PATTERN SETS UP FOR THE
FIRST HALF OF THE WORK WEEK WITH A FEW SHOWERS POSSIBLE FROM TIME
TO TIME. THEN TEMPERATURES WILL BEGIN TO MODERATE TOWARD THE END
OF THE WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
THE REMAINDER THE AFTERNOON SHOULD LARGELY BE DRY...WITH VISIBLE
SATELLITE SHOWING A SIGNIFICANT DRY SLOT WHICH IS ROUGHLY ALIGNED
WITH WEAK MID-LEVEL RIDGING. SHOWERS AND POSSIBLY A THUNDERSTORM
MAY CLIP THE SAINT LAWRENCE VALLEY...WITH SOME LIGHT SHOWERS OR
SPRINKLES POSSIBLE IN THE SOUTHERN TIER...BUT THE VAST MAJORITY OF
THE REGION SHOULD BE DRY WITH A FAIR AMOUNT OF SUNSHINE THROUGH
700 PM. TEMPERATURES WILL BE IN THE UPPER 70S TO LOWER 80S WITH
THE COOLER TEMPERATURES ALONG THE LAKESHORES AND ACROSS HIGHER
TERRAIN.
CONDITIONS WILL DETERIORATE RAPIDLY THIS EVENING...AS STEADIER
RAINS MOVE INTO THE REGION FROM THE OHIO VALLEY. THERE CONTINUES
TO BE A POTENTIAL FOR FLOODING...WITH MOST MESOSCALE 12Z GUIDANCE
CONTINUING TO FORECAST LOCALIZED RAINFALL AMOUNTS OF 2 TO 3
INCHES. THE FORECAST CHALLENGE IS DETERMINING EXACTLY WHEN AND
WHERE THESE AMOUNTS WILL FALL...GIVEN THE CONVECTIVE ELEMENTS OF
AN OTHERWISE SYNOPTIC EVENT.
AN ANOMALOUSLY DEEP 500 MB TROUGH AXIS ACROSS THE CENTRAL GREAT
LAKES THIS AFTERNOON WILL PIVOT ACROSS THE LOWER LAKES...WITH THIS
FORECAST TO STRENGTHEN A SURFACE LOW WHICH WILL TAKE ROUGHLY THE
SAME TRACK. THE UPPER LEVEL TROUGHING AND DIFLUENCE WILL ALIGN
WITH DEEP LOW LEVEL MOISTURE TO PRODUCE LARGE SCALE LIFT ACROSS
OUR REGION TONIGHT INTO MONDAY. ON TOP OF THIS SUBTLE LOW AND MID
LEVEL BOUNDARIES WILL FOCUS THIS MOISTURE...AND IT WILL BE THESE
MESOSCALE FEATURES WHICH PUSH RAINFALL AMOUNTS OVER THE 2 INCH
THRESHOLD. 12Z RUNS OF THE NAM/RGEM HAVE SHIFTED SOUTHEAST WITH THE
HEAVIEST RAINFALL FROM PREVIOUS RUNS...WHILE THE GFS SEEMS TOO
DEEP WITH THE SURFACE LOW. 09Z SREF ENSEMBLES REFLECT 00/06Z
GUIDANCE AND PUT THE BULLS-EYE ACROSS THE NIAGARA FRONTIER...WITH
THE LATEST RUNS OF THE HRRR TENDING TO SUPPORT THESE SOLUTIONS.
BASED ON THIS...HAVE HIGH CONFIDENCE THAT THERE WILL BE HEAVY
RAIN...BUT DO NOT HAVE HIGH CONFIDENCE ON EXACTLY WHERE IT WILL
BE...SINCE IT IS ONLY LIKELY TO IMPACT A PORTION OF THE REGION.
FORECAST FOLLOWED A CONSENSUS OF ALL GUIDANCE...WHICH SUPPORTS THE
CURRENT LOCATION OF THE FLOOD WATCH. THE AREA MOST VULNERABLE IS
THE BUFFALO CREEKS AND URBAN AREAS...WHICH WOULD PROBABLY REACH
FLOOD STAGE IF RAINFALL TOTALS TOP 2 INCHES. LARGER BASINS ARE
LESS LIKELY TO FLOOD...SINCE THE AXIS OF HEAVY RAIN IS LIKELY TO
BE TOO SMALL TO FILL A LARGER BASIN SUCH AS THE GENESEE RIVER.
ALSO...MOST RIVERS AND CREEKS ARE AT FAIRLY LOW FLOWS TO START WITH.
EXPECT STEADY RAIN WITH EMBEDDED THUNDERSTORMS TO REACH WESTERN
PORTIONS OF THE SOUTHERN TIER AROUND SUNSET...THEN SLOWLY SPREAD
NORTHEAST TO BUFFALO LATE THIS EVENING AND ROCHESTER AROUND
MIDNIGHT. THE AXIS OF HEAVY RAIN WILL SHIFT EASTWARD LATE TONIGHT
INTO MONDAY MORNING. MEANWHILE...MODERATE NORTHERLY FLOW WILL BE
IN PLACE...WITH GUSTS TO 25 MPH. THIS UPSLOPE COMPONENT COMBINED
WITH COOLER TEMPERATURES ALOFT AND UPPER LEVEL TROUGHING WILL
CAUSE CLOUDS AND POSSIBLY SHOWERS TO LINGER FOR MUCH OF THE DAY.
COOLER AIR AND CLOUDS KEEP TEMPERATURES IN THE 60S ON
MONDAY...WHICH IS UNSEASONABLY COOL FOR THIS TIME OF YEAR.
&&
.SHORT TERM /MONDAY NIGHT THROUGH TUESDAY NIGHT/...
ANY LINGERING SHOWERS EAST OF LAKE ONTARIO EARLY MONDAY EVENING
WILL END. THERE MAY BE SOME PARTIAL CLEARING AT FIRST BEHIND THE
DEPARTING LOW...BUT THEN SOME WRAP AROUND MOISTURE AND LAKE EFFECT
CLOUDS WILL DEVELOP OVERNIGHT IN THE NORTHWEST UPSLOPE FLOW
REGIME. LAKE INDUCED INSTABILITY WILL BE GREAT ENOUGH FOR SOME
CLOUD COVER...BUT SHOULD NOT BE HIGH ENOUGH FOR SHOWERS GIVEN THE
SHORT FETCH AND LACK OF SYNOPTIC SCALE FORCING.
ON TUESDAY THE LONGWAVE TROUGH WILL BE WELL ESTABLISHED ACROSS THE
GREAT LAKES AND NORTHEAST. THE NEXT LOW LEVEL TROUGH AND DEEPER
MOISTURE WILL REMAIN ACROSS THE CENTRAL AND UPPER LAKES TUESDAY.
THIS WILL LEAVE LITTLE IN THE WAY OF ORGANIZED ASCENT OVER THE LOWER
LAKES. COLD AIR ALOFT AND WEAK LAKE AND TERRAIN INDUCED CONVERGENCE
ZONES MAY SUPPORT A FEW WIDELY SCATTERED SHOWERS DURING THE MIDDAY
AND AFTERNOON...MAINLY INLAND FROM THE LAKESHORES. IT WILL REMAIN ON
THE COOL SIDE...WITH HIGHS ONLY IN THE VERY LOW 70S AT LOWER
ELEVATIONS AND MID 60S ACROSS HIGHER TERRAIN.
TUESDAY NIGHT THE DIURNAL SHOWERS SHOULD END DURING THE EVENING.
OVERNIGHT DEEPER WRAP AROUND MOISTURE AND WEAK ASCENT WILL BEGIN TO
OVERSPREAD WESTERN NY...WHICH MAY SUPPORT A FEW SCATTERED SHOWERS. A
CYCLONIC SOUTHWEST FLOW AND DEEPER MOISTURE COMBINED WITH COOL MID
LEVEL TEMPS MAY ALSO SUPPORT A FEW LAKE EFFECT SHOWERS EAST AND
NORTHEAST OF LAKE ERIE BY WEDNESDAY MORNING.
&&
.LONG TERM /WEDNESDAY THROUGH SATURDAY/...
A DEEP LONGWAVE TROUGH WILL REMAIN OVER THE GREAT LAKES AND
NORTHEAST THROUGH MIDWEEK BEFORE SLOWLY DE-AMPLIFYING AND RETREATING
INTO QUEBEC BY THE END OF THE WEEK. THE MOIST CYCLONIC FLOW WILL
ALLOW A SERIES OF LOW AMPLITUDE SHORTWAVES AND LOW LEVEL TROUGHS TO
CROSS THE REGION. EACH ONE OF THESE WILL SUPPORT SCATTERED SHOWERS
AND THERE WILL ALSO BE THE POTENTIAL FOR SOME LAKE ENHANCEMENT AS
WELL EARLY WEDNESDAY MORNING AND PERHAPS AGAIN LATER WEDNESDAY NIGHT
WITH COOL AIR ALOFT. TEMPERATURES WILL ONLY SLOWLY IMPROVE WEDNESDAY
AND THURSDAY WITH HIGHS IN THE MID 70S AT LOWER ELEVATIONS AND
AROUND 70 ACROSS HIGHER TERRAIN.
THE TROUGH WILL FINALLY RELAX ITS GRIP BY FRIDAY WITH WEAK SURFACE
HIGH PRESSURE BUILDING INTO THE LOWER LAKES. THIS SHOULD FINALLY
BRING A MAINLY DRY DAY WITH TEMPERATURES SLOWLY MOVING BACK CLOSER
TO AVERAGE. THE SLOW WARMING TREND WILL CONTINUE ON SATURDAY...BUT A
CLOSED LOW DEVELOPING OVER THE OHIO VALLEY MAY FORCE ATLANTIC
MOISTURE TO SPREAD NORTH INTO OUR REGION WITH ANOTHER CHANCE OF
SHOWERS AND A FEW THUNDERSTORMS.
&&
.AVIATION /18Z SUNDAY THROUGH FRIDAY/...
WEAK UPPER LEVEL RIDGING SHOULD KEEP CONDITIONS VFR FOR THE
REMAINDER OF THE AFTERNOON.
LOW PRESSURE WILL APPROACH THE REGION TONIGHT...WHICH WILL BRING
STEADY AND SOMETIMES HEAVY RAINFALL TO THE REGION TONIGHT. EXPECT
CIGS/VSBY TO GRADUALLY LOWER TO MVFR THIS EVENING FROM SW- NE AS
THIS LOW APPROACHES THE REGION. THE STRENGTHENING LOW WILL SET UP
A NE FLOW...WHICH IS LIKELY TO BRING EVEN LOWER CONDITIONS LATE
TONIGHT...WITH IFR OR LOWER CIGS A GOOD POSSIBLY. CIGS WILL BE
SLOW TO LIFT ON MONDAY MORNING...WITH A NORTHERLY UPSLOPE FLOW
AND LINGERING MOISTURE.
OUTLOOK...
MONDAY AFTERNOON...GRADUAL IMPROVEMENT FROM IFR/MVFR LATE
AFTERNOON AND EVENING.
TUESDAY THROUGH THURSDAY...MAINLY VFR WITH A CHANCE OF SHOWERS.
FRIDAY...VFR.
&&
.MARINE...
WINDS WILL AVERAGE BETWEEN 10 AND 15 KNOTS TODAY...WITH SOME MODEST
CHOP ALONG THE WESTERN SHORES OF BOTH LAKES...BUT WAVES SHOULD
STAY BELOW SCA CRITERIA THROUGH THIS EVENING.
LOW PRESSURE WILL PIVOT SOUTH OF THE REGION TONIGHT AND THEN WILL
STRENGTHEN ACROSS EASTERN NEW YORK ON SUNDAY. THIS WILL TIGHTEN THE
PRESSURE GRADIENT AND ESTABLISH A MODERATE NORTHERLY FLOW LATE
TONIGHT AND MONDAY. THE 12Z GFS APPEARS OVERDONE...BUT EVEN SO THE
NAM/RGEM ARE STRONGER THAN PREVIOUS RUNS AND SUPPORTS SMALL CRAFT
HEADLINES FOR LAKE ONTARIO...AND THE LOWER NIAGARA RIVER. EVEN
LAKE ERIE BEARS WATCHING...WITH WINDS/WAVES LIKELY TO APPROACH
SMALL CRAFT CRITERIA LATE TONIGHT AND MONDAY MORNING. WINDS WILL
DIMINISH MONDAY NIGHT...WITH A WEAKER FLOW FORECAST FOR MID-WEEK.
&&
.BUF WATCHES/WARNINGS/ADVISORIES...
NY...FLOOD WATCH FROM 10 PM EDT THIS EVENING THROUGH MONDAY
AFTERNOON FOR NYZ001>004-010>014-019>021-085.
MARINE...SMALL CRAFT ADVISORY FROM 5 AM TO 2 PM EDT MONDAY FOR LOZ030.
SMALL CRAFT ADVISORY FROM 2 AM TO 8 PM EDT MONDAY FOR
LOZ042>044.
SMALL CRAFT ADVISORY FROM 5 AM TO 6 PM EDT MONDAY FOR
LOZ045.
&&
$$
SYNOPSIS...APFFEL
NEAR TERM...APFFEL
SHORT TERM...HITCHCOCK
LONG TERM...HITCHCOCK
AVIATION...APFFEL
MARINE...APFFEL
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
123 PM EDT SUN JUL 27 2014
.SYNOPSIS...
A SERIES OF LOW PRESSURE SYSTEMS WILL TRACK FROM THE MIDWEST TO
THE EAST COAST, BRINGING INCREASINGLY HUMID AIR TO THE AREA, ALONG
WITH A GOOD CHANCE OF SHOWERS AND THUNDERSTORMS. THE BEST CHANCE
FOR A WIDESPREAD RAIN LOOKS TO BE SUNDAY NIGHT INTO MONDAY. COOLER
AND DRIER WEATHER WILL FOLLOW BEHIND THESE SYSTEMS TUESDAY AND
WEDNESDAY.
&&
.NEAR TERM /UNTIL 8 PM THIS EVENING/...
1045 AM UPDATE...
SHORT WAVE INDUCED CONVECTION HAS MOVED WELL EASTWARD, LEAVING
ISOLATED TO SCATTERED CELLS OVER THE NORTHERN FA. THE ATMOSPHERE
IS IN RECOVERY MODE AT THIS MOMENT, BUT THERE EXIST INTERESTING
SOUNDINGS UPSTREAM SOUNDINGS (12Z AT BUF, PIT, DTX) WHICH SUGGEST
FUTURE UPSTREAM DEVELOPMENT.
NOTABLE ON THE SOUNDINGS ARE AMPLE DRY AIR INTRUSIONS ALOFT AND
OBVIOUS ELEVATED MIXED LAYERS. SHEAR/HELICITY VALUES ARE MODEST,
BUT APPEAR SUFFICIENT CONSIDERING STRONG MID LEVEL LAPSE RATES.
SPC MESOSCALE PAGE SHOWS AMPLE MID LEVEL LAPSE RATES (>7C)
UPSTREAM, WHILE SPC VALUES ARE ALREADY IN THE 2-4 RANGE FROM THE
CENTRAL SOUTHERN TIER DOWN TOWARD PIT.
WE LACK AN OBVIOUS TRIGGER FOR THE NEXT SEVERAL HOURS, BUT IF WE
CAN GENERATE CONVECTION AHEAD OF THE NEXT WAVE WITHIN A FEW HOURS
OF PEAK HEATING, STRONG CONVECTION WILL BECOME LIKELY LATE IN THE
DAY. WILL NEED TO WATCH CLOSELY.
PREVIOUS DISCUSSION...
RADARS SHOW SOME SCATTERED RAIN SHOWERS JUST CLIPPING FAR
NORTHEAST ONEIDA COUNTY AT THIS TIME. THESE SHOWERS WERE EXITING
NORTH CENTRAL NEW YORK AS A WEAKENING UPPER LEVEL WAVE CONTINUES
TO TRACK EASTWARD TOWARD NEW ENGLAND. WATER VAPOR IMAGERY SHOWS A
MUCH MORE SUBSTANTIAL SHORT WAVE PRESENTLY OVER LOWER MICHIGAN AND
LAKE HURON. THIS FEATURE WAS CAPTURED WELL IN THE TROPOPAUSE
PRESSURE FIELDS FOR THE 1.5 PV UNIT ON THE LATEST RAP MODEL. THIS
FEATURE IS PROJECTED TO TRACK INTO CENTRAL NY BY 12Z. RADAR SHOWS
A SWATH OF SHOWERS AND THUNDERSTORMS OVER ONTARIO WITH MUCH LESS
SOUTHWARD. THE HI RES MESOSCALE MODELS ARE HAVING TROUBLE
SIMULATING THE PRESENT RADAR COVERAGE THUS FEEL THEY LIKELY ARE A
BIT SUSPECT. THE HRRR HAS THE BEST HANDLE SO FAR AND LIKE THE
OTHER HI RESOLUTION MODELS BRINGS A SWATH OF SHOWERS AND
THUNDERSTORMS ACRS CENTRAL NY BTWN 9 AND 12Z. SO AS THIS WAVE
PASSES BY LATER THIS MORNING, I WILL HAVE LIKELY POPS IN NC NY AND
TAPER THEM DOWN TO CHC IN NE PA.
AFTER THIS WAVE PASSES AFTER 12Z...CENTRAL NY AND NORTHEAST PA GETS
INTO A LULL WITH MID-LEVEL SUBSIDENCE. MODELS ALL SHOW A NICE
LOW-LEVEL JET FEATURE TRANSPORTING LOW-LEVEL MOISTURE NORTHWARD
DURING THE ERLY MORNING HOURS WITH THE WAVE THAT WILL PASS ACRS C NY
MENTIONED ABV. HENCE DWPTS ABV THE SURFACE WILL BE HIGH ENOUGH TO MIX
DOWN MID TO UPPER 60S DEW POINTS WITH INSOLATION LATER IN THE MORNING
AND AFTERNOON. SOME LOCALES LIKELY WILL HAVE SFC DEW POINTS IN THE LOWER 70S.
EVENTUALLY BY AFTERNOON THERE WILL BE ENUF SUNSHINE FOR SIGNIFICANT
INSTABILITY TO DEVELOP. I EXPECT CAPES BETWEEN 1000 AND 2000 J/KG
MIXED LAYER. THE WIND SHEAR INITIALLY THIS AFTERNOON IS FAVORABLE
FOR SEVERE WINDS AND POTENTIAL LARGE HAIL. HOWEVER...THERE IS NO
REAL TRIGGER TO FOCUS ANY CONVECTION THIS AFTERNOON. GIVEN THE
POTENTIAL WE CAN NOT RULE OUT AN ISOLATED TO SCT THUNDERSTORM AND
KEPT POPS IN OUR GRIDS BUT BELIEVE BULK OF ACVTY WILL COME SUNDAY
EVENING AND SUNDAY NIGHT AND NEXT MAJOR WAVE AFFECTS THE REGION.
&&
.SHORT TERM /8 PM THIS EVENING THROUGH TUESDAY NIGHT/...
WATER VAPOR IMAGERY SHOWS AN UNSEASONABLY VIGOROUS UPPER LEVEL
LOW RAPIDLY MOVING SOUTHEASTWARD INTO NORTHERN MINN AT THIS TIME.
THIS FEATURE WILL CONTINUE TO DROP SOUTHEASTWARD TODAY AND REACH
OHIO BY 03Z MONDAY AND OPEN UP INTO A TROUGH. THIS FEATURE WILL
PROVIDE THE UPPER LEVEL SUPPORT TO FIRE CONVECTION. THE WAVE WILL
WORK ON SIGNIFICANT INSTABILITY OVER THE LWR OHIO VALLEY TO CNTRL
APPLCNS THIS AFTERNOON AND HENCE SPC/S MODERATE RISK FOR SEVERE
WEATHER DOWN THERE. AS THIS UPPER LEVEL WAVE BEGINS TO TRACK E
INTO PA BTWN 3 AND 6Z...THE INSTABILITY WILL BE WEAKER BUT STILL,
GIVEN THE UPPER LEVEL SUPPORT, AND MIXED LAYER CAPES STILL BETWEEN
1000 AND 2000 J/KG IN NE PA AND SC NY...I THINK THERE WILL BE A
BAND OF STRONG TO SEVERE THUNDERSTORMS WORKING NORTHEAST FROM C PA
INTO NE PA AND EVENTUALLY SC NY BEFORE IT WEAKENS AND STRATIFORM
OUT IN C NY BY 6Z. STILL CONCUR WITH SPC SLGHT RISK...ESPECIALLY
FROM SC NY TO NE PA IN THE WFO BGM FORECAST AREA. FARTHER N...BY
THE TIME THE INFLUENCE OF THIS WAVE REACHES NC NY...INSTABILITY
WILL BE LESS AND THE SHEAR WON/T BE AS STRONG. BUT IN ANY EVENT
WILL CONT TO MENTION CHC FOR SVR THUNDERSTORMS IN HWO MAINLY SUN
EVENING AND NOT TAKE NC NY OUT JUST YET.
THEN BETWEEN 6Z-12Z MON THINGS GET INTERESTING. DUE TO THE DIGGING
UPPER LEVEL TROF AND CONVECTION...ALL SYNOPTIC MODELS INDICATE
THAT A LOW-LEVEL CYCLONE WILL DEVELOP FROM NW PA TO NJ. BY 12Z THE
4 MAIN SYNOPTIC MODELS...EURO...CMC...NAM AND GFS ALL DIFFER IN
THE TIMING OF THE SFC LO. THE EURO IS SLOWEST IN BRINGING IT TO SE
NY BY 18Z MON...WITH THE GFS THE FASTEST HAVING THE SFC LO OVER
NH AT THIS TIME. THE OTHER TWO MODELS ARE IN BETWEEN.
IN ANY EVENT...THE DEVELOPMENT OF THIS LOW-LEVEL CYCLONE WILL PUT
A DEFORMATION ZONE WITH SIGNIFICANT FGEN FORCING ON THE NW SIDE OF
IT...WHICH AS PER NAM...GFS...AND CMC HAS A SWATH OF HEAVY RAIN
FOR PORTIONS OF C NY AND NRN PA BTWN 6Z AND 18Z MONDAY. THE EURO
IS FARTHER W WITH THIS AXIS OF HEAVIER PRECIP. THE INTERESTING
ASPECT OF THIS THAT THERE IS A SLOPED LAYER OF FGEN FORCING ON THE
NW SIDE OF THE LOW WITH CONVECTIVE INSTABILITY ALOFT. THIS COULD
MEAN THAT AS THE BAND OF POTENTIALLY STRONG TO SEVERE STORMS THAT WORKS
NORTHEAST ACR NE PA AND SC NY...SLOWS DOWN AND EVENTUALLY BECOMES
A HEAVY RAIN PRODUCER AS IT STRATIFORM OUT. THE NAM HAS THE
HIGHEST QPF WITH 2.5 TO 3.5 INCHES ACRS C NY. THE OTHER MODELS ARE
TAMER BUT STILL HAVE UP TO 2 INCHES OR MORE. THIS COULD MEAN LOCALLY
THAT RAINFALL WHICH COULD EXCEED THREE OR EVEN FOUR INCHES LOCALLY SO
WILL HAVE TO WATCH OUT FOR THE POTENTIAL FOR FLASH FLOODING SUN
NGT AS WELL. WILL MENTION IN HWO.
FOR MONDAY DURING THE DAY...THE SFC LO PULLS OUT TO THE NE AND THE
RAINFALL STARTS TO WIND DOWN FROM SW-NE LATE IN THE DAY. THE EURO IS
SLOWEST BRINGING THE PRECIP OUT WITH THE NAM AND GFS THE FASTEST.
WILL MAINTAIN LINGERING SHRA MOST OF THE DAY AS PER SURROUNDING
OFFICES GRIDS. WOULDN`T BE SURPRISED IF PRECIP ENDS A BIT QUICKER
THAN CURRENTLY ADVERTISED MON PM THOUGH.
FOR MON NGT...ONLY THE EURO HAS LINGERING PRECIP FOR THE CATSKILLS
TO THE UPPER MOHAWK VALLEY. REST OF MODELS ARE BASICALLY DRY. FOR
NOW WILL GO WITH EURO/S AND SURROUNDING OFFICES IDEA OF SLGHT CHC
TO CHC SHRA MON EVE...THEN END PRECIP AFTER MIDNIGHT INTO ERLY
TUESDAY.
FOR TUE... HAVE POP UP SHRA GIVEN THE COLDER AIR ALOFT. TUE NGT
WILL SEE HIGH PRESSURE AND FAIR WEATHER. A FEW LINGERING SHRA
STILL POSSIBLE IN THE FINGER LAKES REGION CLOSER TO THE NEXT WAVE.
&&
.LONG TERM /WEDNESDAY THROUGH SATURDAY/...
430 AM UPDATE...NO SIGNIFICANT CHANGES TO EXTENDED JUST REFRESHED
WITH LATEST WPC GUIDANCE. UPPER LEVEL TROF AXIS WILL REMAIN JUST
WEST OF AREA THROUGHOUT PERIOD. EACH DAY WILL CONTINUE TO CARRY
SLIGHT CHC/CHC POPS DURING THE AFTERNOON FOR DIURNAL CONVECTION
UNDER AN EVER PERSISTENT EASTERN TROF. TEMPS WILL RUN SEVERAL
DEGREES BELOW SEASONAL LEVELS.
145 PM UPDATE...
HIPRES AT THE SFC WL BE OVR THE CWA AT THE START OF THE LONG TERM
PD. HWVR FLOW ALOFT WL BE DOMINATED BY A L/WV TROF. THIS WL KEEP
SLGT CHCS FOR AFTN SHRA/TSRA THRU THE END OF THE WEEK AND GIVE
CREDENCE TO THE WORDS "DIRTY HIGH." HV BASICALLY FOLLOWED WPC
GUIDANCE WITH 20 POPS EACH AFTN ALONG WITH NR NORMAL TEMPS, WITH
HIGHS ARND 80 AND LOWS IN THE 50S EXPECTED EACH PERIOD.
&&
.AVIATION /18Z SUNDAY THROUGH THURSDAY/...
18Z SUN UPDATE... MAINLY VFR IS EXPECTED THIS AFTN. ISOLD
SHWRS/TSTMS ARE PSBL...SPCLY IN THE VICINITY OF KSYR/KRME...BUT
WE`VE NOT ADDED TO THE TERMINAL FCSTS ATTM DUE TO THEIR
ANTICIPATED SPARSE COVERAGE.
SHWRS/EMBEDDED TSTMS WILL BECOME MORE WIDESPREAD THIS
EVE/OVERNIGHT. THUS...WE`VE GONE WITH AREA-WIDE MVFR
RESTRICTIONS...WITH THE POTENTIAL FOR IFR CONDS MOST READILY SEEN
ON THE HILLTOPS AT KBGM AND KITH. TSTMS SEEM MOST LIKELY AT THE
LEADING EDGE OF THIS ACTIVITY EARLY THIS EVE...SO WE`VE INSERTED
TEMPO GROUPS FOR TSRA ONLY AT KELM AND KAVP FOR THE TIME BEING.
MON MRNG...CONDS SHOULD BE VERY SLOW TO IMPROVE...THEREFORE
RESTRICTIONS (MAINLY MVFR) ARE LIKELY TO PERSIST.
W TO SW SFC WINDS ARND 10 KT ARE EXPECTED THIS AFTN. WINDS WILL
BECOME LGT AND VRBL TNT...BEFORE SHIFTING INTO THE N AND NW
MON...AND INCREASING TO 10-15 KT.
OUTLOOK...
TUE-THU...RESTRICTIONS POSSIBLE EACH AFTERNOON...WITH SCTD
SHWRS/TSTMS ANTICIPATED.
&&
.BGM WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NY...NONE.
&&
$$
SYNOPSIS...DJN
NEAR TERM...DJN/DJP
SHORT TERM...DJN
LONG TERM...PVN/RRM
AVIATION...MLJ
AREA FORECAST DISCUSSION
NWS RALEIGH NC
655 PM EDT SUN JUL 27 2014
.SYNOPSIS...A SURFACE TROUGH WILL PERSIST OVER THE CAROLINAS THROUGH
TONIGHT. A STRONG COLD FRONT WILL CROSS THE AREA ON MONDAY...
BRINGING NOTICEABLY COOLER AND LESS HUMID AIR INTO THE AREA. HIGH
PRESSURE BUILDS OVER MUCH OF THE REGION FOR TUESDAY INTO WEDNESDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 340 PM SUNDAY...
AFTER A COOL START OWING TO ABUNDANT MULTI-LAYERED CLOUDS AND
RAIN...TEMPERATURES HAVE CLIMBED QUICKLY DURING THE PAST FEW HOURS
IN AN AREA OF CLEARING IN THE WAKE OF THE MORNING MCV...COINCIDENT
WITH THE ARRIVAL OF THE LEADING EDGE OF HOT/22C 12Z-OBSERVED H85
TEMPS AT KBNA. THE CONFIGURATION OF THE WAA REGIME DEVELOPING FROM
THE WESTERN CAROLINAS AND EARLIER RAIN-COOLED AIR WILL FAVOR THE
STRENGTHENING OF A NW TO SE-ORIENTED OUTFLOW BOUNDARY/EFFECTIVE
FRONT FROM THE TN VALLEY SOUTHEASTWARD ACROSS SOUTHERN VA/NORTHERN
NC. THIS BOUNDARY WILL SERVE TO ENHANCE WHAT NEAR TERM GUIDANCE
SUGGESTS WILL BE ALREADY STRONG LOW LEVEL SHEAR IN THE 250-400 MS/S2
RANGE CENTERED OVER SOUTHSIDE VA AND NORTH-CENTRAL NC...FROM JUST
PRIOR TO SUNSET THROUGH MIDNIGHT. MID-LEVEL/DEEP LAYER WINDS WILL BE
EQUALLY IMPRESSIVE...AS THE EXIT REGION OF AN UPSTREAM MID LEVEL JET
AT THE BASE OF THE UPPER MID WEST UPPER LOW EMERGES EAST OF THE
CENTRAL APPALACHIANS AND STRENGTHENS KGSO AND KRNK 12Z-OBSERVED MID
LEVEL FLOW OF ALREADY RESPECTABLE 35-40 KTS...INTO THE 45-55 KT
RANGE THIS EVENING. THE STRONGLY SHEARED ENVIRONMENT WILL SUPPORT A
CONDITIONAL PROBABILITY OF SEVERE THUNDERSTORMS OVER CENTRAL
NC...PARTICULARLY FROM LATE THIS AFTERNOON THROUGH MIDNIGHT.
IT IS PROBABLE THAT SCATTERED STORMS WILL DEVELOP INVOF THE OUTFLOW
BOUNDARY/EFFECTIVE FRONT FROM SOUTHWEST VA INTO THE NORTHERN NC
PIEDMONT...ON THE SOUTHERN FRINGE OF AN MCV MOVING ESE INTO WEST-
CENTRAL VA THIS AFTERNOON...AND AMIDST INCREASING LARGE SCALE LIFT
AHEAD OF THE UPPER LOW APPROACHING FROM THE UPPER MIDWEST. THE LAST
SEVERAL RUNS OF THE HRRR HAVE FINALLY PICKED UP ON THIS POTENTIAL.
WILL ADVERTISE A CHANCE OF STORMS MAINLY OVER THE NORTHERN HALF OF
THE FORECAST AREA (INVOF THE BOUNDARY) THROUGH THIS EVENING...WITH
AN ASSOCIATED CONDITIONAL PROBABILITY OF A MULTI-FACETED SVR RISK OF
DAMAGING WINDS...LARGE HAIL...AND EVEN AN ISOLATED TORNADO GIVEN THE
EXPECTED STRONG LOW LEVEL SHEAR CENTERED OVER THE NE PIEDMONT AROUND
00Z.
NWP GUIDANCE THEN SUGGESTS THAT STORMS OVER THE TN VALLEY THIS
AFTERNOON WILL DEVELOP SOUTHEASTWARD AND SPREAD ACROSS THE CENTRAL
APPALACHIANS LATE THIS EVENING...AND INTO CENTRAL NC AFTER LOW LEVEL
SHEAR DIMINISHES - AND WHEN CINH SHOULD BE MAXIMIZED - DURING THE
OVERNIGHT HOURS. ANY OVERNIGHT CONVECTION WOULD THEN POSE PRIMARILY
A THREAT OF DAMAGING WIND AND LARGE HAIL MAINLY OVER THE NW
PIEDMONT...BEFORE STORMS WEAKEN AS THEY MOVE SOUTHEAST INTO THE
REMAINDER OF CENTRAL NC. THOUGH THERE REMAINS OPPOSING SIGNALS FOR
STORM DEVELOPMENT/MAINTENANCE (IE. STRONG AND INCREASING FORCING FOR
ASCENT DOWNSTREAM OF THE DEEP UPPER LOW VERSUS STRONG CINH (NEAR 200
J/KG)...THE OVERWHELMING SIGNAL FROM NWP GUIDANCE IS FOR THE CINH TO
WIN OUT AND CAUSE STORMS TO DIMINISH INVOF HWY 64 BY LATE THIS
EVENING...SENDING ONLY A SURGING OUTFLOW BOUNDARY AND ASSOCIATED NW
WIND GUSTS OF 25-35 KTS (STRONGEST NORTH) SOUTH THROUGH THE
REMAINDER OF THE CENTRAL NC OVERNIGHT. REGARDLESS...IT WILL BE MUGGY
AND QUITE MILD OVERNIGHT...WITH LOWS GENERALLY IN THE MIDDLE 70S.
&&
.SHORT TERM /MONDAY AND MONDAY NIGHT/...
AS OF 325 PM SUNDAY...
NWP GUIDANCE CONTINUES TO SUGGEST DESTABILIZATION WILL BE LIMITED
AND CONFINED TO THE SANDHILLS AND COASTAL PLAIN...GIVEN THE FASTER
TREND NOTED IN NWP GUIDANCE WITH THE PASSAGE OF THE COLD FRONT
THROUGH ALL BUT THE SOUTHEASTERN THIRD OF THE FORECAST AREA BY 18Z
MON. INDEED...WESTERLY DOWNSLOPE FLOW WILL VEER THE SFC FLOW/LIMIT
CONVERGENCE AND AUGMENT DRY ADVECTION BEHIND THE FRONT (AND LIKELY
CAUSE THE FRONT TO ACCELERATE/MERGE WITH THE PRECEDING LEE
TROUGH)...AND CONSEQUENTLY CAUSE SFC DEWPOINTS TO MIX INTO THE LOWER
60S (AND EVEN SOME UPPER 50S POSSIBLE) OVER THE PIEDMONT - YIELDING
LITTLE BOUYANCY. TO THE EAST...IN THE PRE-FRONTAL AIR MASS OVER THE
SANDHILLS AND SOUTHERN AND CENTRAL COASTAL PLAIN...A RESERVOIR OF
UPPER 60S TO LOWER 70S SFC DEWPOINTS WILL REMAIN UNTIL THE FRONT
CROSSES THOSE AREAS DURING THE MID-AFTERNOON HOURS. MORE FAVORABLE
DIURNAL FRONTAL TIMING THERE WILL ALLOW FOR STRONG DIURNAL
HEATING/DESTABILIZATION/STEEPENING OF LOW LEVEL LAPSE RATES...
BENEATH A LINGERING PLUME OF STEEP MID LEVEL LAPSE RATES IN EXCESS
OF 7 C/KM. THESE EXPECTED STEEP LOW-MID LEVEL LAPSE RATES AMIDST
UNSEASONABLY STRONG MID LEVEL FLOW IN THE 40-50 KT RANGE - AND
ASSOCIATED LONG AND STRAIGHT FORECAST HODOGRAPHS AT KFAY AT TIME OF
FROPA AROUND 21Z - WILL SUPPORT A CONDITIONAL RISK OF DAMAGING WIND
GUSTS AND LARGE HAIL LIKELY FROM SPLITTING SUPERCELLS...PROVIDED
STORMS INDEED DEVELOP. THIS RISK WILL BE GREATEST ROUGHLY FROM
GOLDSBORO TO FAYETTEVILLE TO LAURINBURG AND ESPECIALLY POINTS
EAST...TO COASTAL AREAS.
LOW LEVEL THICKNESS VALUES AROUND 1425 METERS SUPPORT HIGH
TEMPERATURES IN THE MID-UPPER 80S NW TO LOWER-MID 90S SE. COOLER MON
NIGHT...WITH LOWS RANGING FROM LOWER 60W NW TO MID-UPPER 60 SE.
&&
.LONG TERM /TUESDAY THROUGH SUNDAY/...
AS OF 315 PM SUNDAY...
STRONGLY BLOCKED FLOW AROUND THE NORTHERN HEMISPHERE WILL LEAD TO A
RELATIVELY UNCHANGED WEATHER PATTERN FROM TUESDAY THROUGH THE END OF
NEXT WEEK. THE TROUGH/RIDGE PATTERN OVER THE CONUS WILL AMPLIFY
WITH AN UNSEASONABLY DEEP UPPER TROUGH OVER THE EASTERN US. IN THE
WAKE OF MONDAY`S SYSTEM...PW DROPS BELOW ONE INCH AND THE MEAN
TROUGH AXIS SETS UP NEARLY OVERHEAD. DEWPOINTS ARE PROGGED TO DROP
WELL INTO THE 50S IN THE PIEDMONT...WITH THICKNESSES SUGGESTING
TEMPS 5-10 DEGREES BELOW NORMAL IN THE LOW TO MID 80S. THUS...
PRECIP CHANCES LOOK VERY SMALL THROUGH THURSDAY. HEADING INTO NEXT
WEEKEND...MODELS SHOW ANOTHER SHORTWAVE REINFORCING THE UPPER TROUGH
OVER THE EASTERN CONUS...THOUGH ALSO SHIFTING THE TROUGH AXIS
WESTWARD TOWARD THE MIDWEST STATES. WITH AN FRONTAL ZONE/INVERTED
TROUGH LINGERING NEAR THE COAST OR SLOWLY DRIFTING
INLAND....MOISTURE RETURN AND A MORE FAVORABLE POSITION FOR
INFLUENCE FROM DISTURBANCES ROUNDING THE BASE OF THE TROUGH SHOULD
SLOWLY INCREASE CHANCES FOR PRECIP...WITH INCREASING CLOUD COVER
THROUGH THE WEEKEND. HIGHS LOOK TO REMAIN A GOOD 5-10 DEGREES BELOW
NORMAL.
&&
.AVIATION /00Z MONDAY THROUGH FRIDAY/...
AS OF 655 PM SUNDAY...
GOOD INSTABILITY EAST OF THE MOUNTAINS INTO THE PIEDMONT THIS
EVENING WITH A COMPLEX OF SHOWERS AND THUNDERSTORMS MOVING SOUTHEAST
INTO THE STATE. GUIDANCE POPS ARE LOW IN GENERAL...AND THE
CONVECTIVE ALLOWING MODELS HAVE NOT BEEN HELPFUL OVERALL IN THEIR
FORECASTS OF SHOWER AND THUNDERSTORM DEVELOPMENT IN AND NEAR CENTRAL
NORTH CAROLINA. A FEW SHOWERS HAVE DEVELOPED JUST WEST AND SOUTHWEST
OF THE TRIAD...AND AHEAD OF THE COMPLEX OF STORMS...THINK THERE IS
ENOUGH SHEAR AND INSTABILITY...AND SIMPLE DYNAMICS FROM THE ONGOING
STORMS...SIMILAR TO THE LATEST TREND OF RAP FORECASTS...TO ALLOW FOR
SOME CONTINUED PROGRESSION OF ACTIVITY INTO AND THROUGH CENTRAL
NORTH CAROLINA. TAFS WILL LIKELY INCLUDE A MENTION OF THUNDER AND
GUSTY WINDS...SHOWERS AND LESSER GUSTS CURRENTLY TOWARD KRWI.
CONFIDENCE IS ONLY MODEST...AND AVIATION INTERESTS SHOULD KEEP
ABREAST OF THE LATEST OBSERVATIONAL AND RADAR TRENDS THROUGH THE
EVENING HOURS.
LATE TONIGHT INTO MONDAY...OVERALL DRIER AIR MOVES INTO CENTRAL
NORTH CAROLINA. WITH MIXING MONDAY...WINDS SHOULD BECOME 250-290 AND
WITH MODEST GUSTS TO AT OR SLIGHTLY ABOVE 20KT. A SHOWER OR
THUNDERSTORM IS POSSIBLE TOWARD KFAY AND KRWI MONDAY AFTERNOON BUT
CONFIDENCE IN THEIR DEVELOPMENT AND LOCATION IS TOO LOW TO INCLUDE
IN THE 00Z TAF. BEYOND THE 00Z VALID TAF PERIOD...VFR CONDITIONS
SHOULD PREVAIL FOR MUCH OF THE REST OF THE WORK WEEK...WITH
INCREASING CHANCES FOR SHOWERS AND THUNDERSTORMS FROM FRIDAY INTO
THE WEEKEND.
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...MWS/DJF
NEAR TERM...MWS
SHORT TERM...MWS
LONG TERM...BLS
AVIATION...DJF
AREA FORECAST DISCUSSION
NWS RALEIGH NC
342 PM EDT SUN JUL 27 2014
.SYNOPSIS...A SURFACE TROUGH WILL PERSIST OVER THE CAROLINAS THROUGH
TONIGHT. A STRONG COLD FRONT WILL CROSS THE AREA ON MONDAY...
BRINGING NOTICEABLY COOLER AND LESS HUMID AIR INTO THE AREA.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 340 PM SUNDAY...
AFTER A COOL START OWING TO ABUNDANT MULTI-LAYERED CLOUDS AND
RAIN...TEMPERATURES HAVE CLIMBED QUICKLY DURING THE PAST FEW HOURS
IN AN AREA OF CLEARING IN THE WAKE OF THE MORNING MCV...COINCIDENT
WITH THE ARRIVAL OF THE LEADING EDGE OF HOT/22C 12Z-OBSERVED H85
TEMPS AT KBNA. THE CONFIGURATION OF THE WAA REGIME DEVELOPING FROM
THE WESTERN CAROLINAS AND EARLIER RAIN-COOLED AIR WILL FAVOR THE
STRENGTHENING OF A NW TO SE-ORIENTED OUTFLOW BOUNDARY/EFFECTIVE
FRONT FROM THE TN VALLEY SOUTHEASTWARD ACROSS SOUTHERN VA/NORTHERN
NC. THIS BOUNDARY WILL SERVE TO ENHANCE WHAT NEAR TERM GUIDANCE
SUGGESTS WILL BE ALREADY STRONG LOW LEVEL SHEAR IN THE 250-400 MS/S2
RANGE CENTERED OVER SOUTHSIDE VA AND NORTH-CENTRAL NC...FROM JUST
PRIOR TO SUNSET THROUGH MIDNIGHT. MID-LEVEL/DEEP LAYER WINDS WILL BE
EQUALLY IMPRESSIVE...AS THE EXIT REGION OF AN UPSTREAM MID LEVEL JET
AT THE BASE OF THE UPPER MID WEST UPPER LOW EMERGES EAST OF THE
CENTRAL APPALACHIANS AND STRENGTHENS KGSO AND KRNK 12Z-OBSERVED MID
LEVEL FLOW OF ALREADY RESPECTABLE 35-40 KTS...INTO THE 45-55 KT
RANGE THIS EVENING. THE STRONGLY SHEARED ENVIRONMENT WILL SUPPORT A
CONDITIONAL PROBABILITY OF SEVERE THUNDERSTORMS OVER CENTRAL
NC...PARTICULARLY FROM LATE THIS AFTERNOON THROUGH MIDNIGHT.
IT IS PROBABLE THAT SCATTERED STORMS WILL DEVELOP INVOF THE OUTFLOW
BOUNDARY/EFFECTIVE FRONT FROM SOUTHWEST VA INTO THE NORTHERN NC
PIEDMONT...ON THE SOUTHERN FRINGE OF AN MCV MOVING ESE INTO WEST-
CENTRAL VA THIS AFTERNOON...AND AMIDST INCREASING LARGE SCALE LIFT
AHEAD OF THE UPPER LOW APPROACHING FROM THE UPPER MIDWEST. THE LAST
SEVERAL RUNS OF THE HRRR HAVE FINALLY PICKED UP ON THIS POTENTIAL.
WILL ADVERTISE A CHANCE OF STORMS MAINLY OVER THE NORTHERN HALF OF
THE FORECAST AREA (INVOF THE BOUNDARY) THROUGH THIS EVENING...WITH
AN ASSOCIATED CONDITIONAL PROBABILITY OF A MULTI-FACETED SVR RISK OF
DAMAGING WINDS...LARGE HAIL...AND EVEN AN ISOLATED TORNADO GIVEN THE
EXPECTED STRONG LOW LEVEL SHEAR CENTERED OVER THE NE PIEDMONT AROUND
00Z.
NWP GUIDANCE THEN SUGGESTS THAT STORMS OVER THE TN VALLEY THIS
AFTERNOON WILL DEVELOP SOUTHEASTWARD AND SPREAD ACROSS THE CENTRAL
APPALACHIANS LATE THIS EVENING...AND INTO CENTRAL NC AFTER LOW LEVEL
SHEAR DIMINISHES - AND WHEN CINH SHOULD BE MAXIMIZED - DURING THE
OVERNIGHT HOURS. ANY OVERNIGHT CONVECTION WOULD THEN POSE PRIMARILY
A THREAT OF DAMAGING WIND AND LARGE HAIL MAINLY OVER THE NW
PIEDMONT...BEFORE STORMS WEAKEN AS THEY MOVE SOUTHEAST INTO THE
REMAINDER OF CENTRAL NC. THOUGH THERE REMAINS OPPOSING SIGNALS FOR
STORM DEVELOPMENT/MAINTENANCE (IE. STRONG AND INCREASING FORCING FOR
ASCENT DOWNSTREAM OF THE DEEP UPPER LOW VERSUS STRONG CINH (NEAR 200
J/KG)...THE OVERWHELMING SIGNAL FROM NWP GUIDANCE IS FOR THE CINH TO
WIN OUT AND CAUSE STORMS TO DIMINISH INVOF HWY 64 BY LATE THIS
EVENING...SENDING ONLY A SURGING OUTFLOW BOUNDARY AND ASSOCIATED NW
WIND GUSTS OF 25-35 KTS (STRONGEST NORTH) SOUTH THROUGH THE
REMAINDER OF THE CENTRAL NC OVERNIGHT. REGARDLESS...IT WILL BE MUGGY
AND QUITE MILD OVERNIGHT...WITH LOWS GENERALLY IN THE MIDDLE 70S.
&&
.SHORT TERM /MONDAY AND MONDAY NIGHT/...
AS OF 325 PM SUNDAY...
NWP GUIDANCE CONTINUES TO SUGGEST DESTABILIZATION WILL BE LIMITED
AND CONFINED TO THE SANDHILLS AND COASTAL PLAIN...GIVEN THE FASTER
TREND NOTED IN NWP GUIDANCE WITH THE PASSAGE OF THE COLD FRONT
THROUGH ALL BUT THE SOUTHEASTERN THIRD OF THE FORECAST AREA BY 18Z
MON. INDEED...WESTERLY DOWNSLOPE FLOW WILL VEER THE SFC FLOW/LIMIT
CONVERGENCE AND AUGMENT DRY ADVECTION BEHIND THE FRONT (AND LIKELY
CAUSE THE FRONT TO ACCELERATE/MERGE WITH THE PRECEDING LEE
TROUGH)...AND CONSEQUENTLY CAUSE SFC DEWPOINTS TO MIX INTO THE LOWER
60S (AND EVEN SOME UPPER 50S POSSIBLE) OVER THE PIEDMONT - YIELDING
LITTLE BOUYANCY. TO THE EAST...IN THE PRE-FRONTAL AIR MASS OVER THE
SANDHILLS AND SOUTHERN AND CENTRAL COASTAL PLAIN...A RESERVOIR OF
UPPER 60S TO LOWER 70S SFC DEWPOINTS WILL REMAIN UNTIL THE FRONT
CROSSES THOSE AREAS DURING THE MID-AFTERNOON HOURS. MORE FAVORABLE
DIURNAL FRONTAL TIMING THERE WILL ALLOW FOR STRONG DIURNAL
HEATING/DESTABILIZATION/STEEPENING OF LOW LEVEL LAPSE RATES...
BENEATH A LINGERING PLUME OF STEEP MID LEVEL LAPSE RATES IN EXCESS
OF 7 C/KM. THESE EXPECTED STEEP LOW-MID LEVEL LAPSE RATES AMIDST
UNSEASONABLY STRONG MID LEVEL FLOW IN THE 40-50 KT RANGE - AND
ASSOCIATED LONG AND STRAIGHT FORECAST HODOGRAPHS AT KFAY AT TIME OF
FROPA AROUND 21Z - WILL SUPPORT A CONDITIONAL RISK OF DAMAGING WIND
GUSTS AND LARGE HAIL LIKELY FROM SPLITTING SUPERCELLS...PROVIDED
STORMS INDEED DEVELOP. THIS RISK WILL BE GREATEST ROUGHLY FROM
GOLDSBORO TO FAYETTEVILLE TO LAURINBURG AND ESPECIALLY POINTS
EAST...TO COASTAL AREAS.
LOW LEVEL THICKNESS VALUES AROUND 1425 METERS SUPPORT HIGH
TEMPERATURES IN THE MID-UPPER 80S NW TO LOWER-MID 90S SE. COOLER MON
NIGHT...WITH LOWS RANGING FROM LOWER 60W NW TO MID-UPPER 60 SE.
&&
.LONG TERM /TUESDAY THROUGH SUNDAY/...
AS OF 315 PM SUNDAY...
STRONGLY BLOCKED FLOW AROUND THE NORTHERN HEMISPHERE WILL LEAD TO A
RELATIVELY UNCHANGED WEATHER PATTERN FROM TUESDAY THROUGH THE END OF
NEXT WEEK. THE TROUGH/RIDGE PATTERN OVER THE CONUS WILL AMPLIFY
WITH AN UNSEASONABLY DEEP UPPER TROUGH OVER THE EASTERN US. IN THE
WAKE OF MONDAY`S SYSTEM...PW DROPS BELOW ONE INCH AND THE MEAN
TROUGH AXIS SETS UP NEARLY OVERHEAD. DEWPOINTS ARE PROGGED TO DROP
WELL INTO THE 50S IN THE PIEDMONT...WITH THICKNESSES SUGGESTING
TEMPS 5-10 DEGREES BELOW NORMAL IN THE LOW TO MID 80S. THUS...
PRECIP CHANCES LOOK VERY SMALL THROUGH THURSDAY. HEADING INTO NEXT
WEEKEND...MODELS SHOW ANOTHER SHORTWAVE REINFORCING THE UPPER TROUGH
OVER THE EASTERN CONUS...THOUGH ALSO SHIFTING THE TROUGH AXIS
WESTWARD TOWARD THE MIDWEST STATES. WITH AN FRONTAL ZONE/INVERTED
TROUGH LINGERING NEAR THE COAST OR SLOWLY DRIFTING
INLAND....MOISTURE RETURN AND A MORE FAVORABLE POSITION FOR
INFLUENCE FROM DISTURBANCES ROUNDING THE BASE OF THE TROUGH SHOULD
SLOWLY INCREASE CHANCES FOR PRECIP...WITH INCREASING CLOUD COVER
THROUGH THE WEEKEND. HIGHS LOOK TO REMAIN A GOOD 5-10 DEGREES BELOW
NORMAL.
&&
.AVIATION /18Z SUNDAY THROUGH FRIDAY/...
AS OF 205 PM SUNDAY...
SCATTERED SHOWERS AND STORMS...WHOSE PROBABILITY OF OCCURRENCE AT
ANY PARTICULAR TERMINAL IS ONLY AROUND 20 PERCENT...MAY FORM IN-SITU
OVER CENTRAL NC THIS AFTERNOON...IN ASSOCIATION WITH LIFT AHEAD OF A
MID LEVEL DISTURBANCE MOVING INTO SOUTH-CENTRAL VA...AND IN THE
VICINITY OF AN OUTFLOW BOUNDARY FROM NEAR KMTV TO KRDU TO KCTZ. IN
ADDITION...A BRIEF PERIOD OF MVFR CEILINGS WILL BE POSSIBLE ON THE
COOL SIDE OF THE OUTFLOW BOUNDARY (AT KRWI) THROUGH 20Z. ANOTHER
CLUSTER OF SHOWERS AND STORMS...THE ONE CURRENTLY DEVELOPING OVER
EASTERN KY...IS FORECAST TO SPREAD SOUTHEASTWARD AND INTO CENTRAL
NC...LIKELY IN A GRADUALLY WEAKENING STATE...BETWEEN 02-08Z. THE
RELATIVE BEST CHANCE OF STORMS WILL BE AT TRIAD TERMINALS...WITH
PROGRESSIVELY LOWER PROBABILITIES TOWARD KRDU/KRWI AND ESPECIALLY
KFAY. DESPITE THE PROBABLE WEAKENING OF THE STORMS AS THEY MOVE INTO
CENTRAL NC...A WELL-ORGANIZED OUTFLOW BOUNDARY AND ASSOCIATED
NORTHWESTERLY WIND GUSTS OF 25-35 KTS (STRONGEST AT KRDU/KRWI) MAY
SURGE ALL THE WAY SOUTH THROUGH CENTRAL NC OVERNIGHT.
A BREEZY WSW WIND EARLY MONDAY WILL VEER TO WEST OR WNW WITH THE
PASSAGE OF A PRONOUNCED COLD FRONT MONDAY AFTERNOON. THE FRONT IS
FORECAST TO BE A DRY ONE FOR MOST OF CENTRAL NC...WITH AROUND A 30
PERCENT CHANCE OF A STORM AT KRWI AND KFAY...AND HIGHER
PROBABILITIES TOWARD COASTAL AREAS.
PREDOMINATELY VFR CONDITIONS ARE OTHERWISE EXPECTED THROUGHOUT THE
FORECAST PERIOD...AS CANADIAN HIGH PRESSURE BECOMES CENTERED OVER
THE TN VALLEY AND CENTRAL APPALACHIANS THROUGH MID-WEEK.
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...MWS
NEAR TERM...MWS
SHORT TERM...MWS
LONG TERM...BLS
AVIATION...MWS
AREA FORECAST DISCUSSION
NWS GRAND FORKS ND
1232 PM CDT SUN JUL 27 2014
.UPDATE...
ISSUED AT 1232 PM CDT SUN JUL 27 2014
CLOUDS ARE STAYING PRETTY THICK ACROSS THE AREA SO WILL INCREASE
CLOUD AMOUNTS THROUGH THE REST OF THE AFTERNOON. THIS WILL ALSO
RESULT IN HIGH TEMPS A LITTLE COOLER THAN EXPECTED.
&&
.SHORT TERM...(TODAY THROUGH MONDAY)
ISSUED AT 246 AM CDT SUN JUL 27 2014
HOW MUCH PRECIP HANGS AROUND AS THE UPPER LOW MOVES OFF TO THE
EAST WILL BE THE MAIN FORECAST QUESTION FOR THE PERIOD.
SCATTERED SHOWERS CONTINUE FROM THE RED RIVER VALLEY EASTWARD AS
THE UPPER LOW SLOWLY MOVES SOUTHEASTWARD INTO NORTHERN MINNESOTA.
THE UPPER LOW WILL CONTINUE OFF INTO WI DURING THE DAY...WITH THE
SFC LOW ALSO HEADING OFF AND HIGH PRESSURE BUILDING INTO THE
REGION. THE BEST LIFT WITH THE UPPER LOW WILL EXIT THE AREA FAIRLY
EARLY IN THE DAY. HOWEVER...CONVECTIVE TEMPS REMAIN IN THE UPPER
60S TO LOW 70S...SO SOME REDEVELOPMENT IS NOT OUT OF THE QUESTION
AND THE HRRR SEEMS TO SHOW THIS TREND. THUS...CONTINUED TO KEEP
LOW POPS GOING THROUGH 00Z. TEMPS WILL BE MOSTLY IN THE LOW 70S
WITH NORTH WINDS LESS BREEZY THAN YESTERDAY.
NORTHWESTERLY FLOW ALOFT SETS UP FOR TONIGHT AND CONTINUES INTO
MONDAY. SFC HIGH PRESSURE WILL REMAIN OVER THE NORTHERN PLAINS AND
BRING LIGHT NORTH WINDS. THE NAM WAS SHOWING SOME SIGNS OF A WEAK
SHORTWAVE IN THE NORTHWESTERLY FLOW APPROACHING THE LAKE OF THE
WOODS AREA AND BRINGING SOME ADDITIONAL PRECIP. HOWEVER...IT SEEMS
TO BE AN OUTLIER SO WILL KEEP IT DRY FOR NOW. LOWS TONIGHT SHOULD
DROP QUITE NICELY TO THE LOW 50S UNDER THE SFC HIGH...WITH
AFTERNOON TEMPS ON MONDAY GETTING INTO THE 70S.
.LONG TERM...(MONDAY NIGHT THROUGH SATURDAY)
ISSUED AT 246 AM CDT SUN JUL 27 2014
MONDAY NIGHT THROUGH TUESDAY NIGHT...NORTHWESTERLY FLOW ALOFT AND
SFC HIGH PRESSURE CONTINUE. WITH NOTHING TO FORCE THUNDERSTORM
DEVELOPMENT AND NOT EVEN ANY REAL RETURN FLOW...EXPECT US TO
REMAIN DRY THROUGH THE EARLY PART OF THE WORK WEEK. TEMPS WILL
CONTINUE TO BE SLIGHTLY BELOW SEASONAL AVERAGES ALTHOUGH THEY
SHOULD SLOWLY WARM.
WEDNESDAY-SATURDAY...MAINLY DRY CONDITIONS WITH SEASONABLE TEMPS AND
LIGHT WINDS WILL CONTINUE INTO NEXT WEEKEND...AS THE EASTERN US
TROUGH/WESTERN US RIDGE KEEPS THE NORTHERN PLAINS REGION IN A VERY
QUIET NORTHWEST FLOW PATTERN. ANY PRECIP CHANCES WITH WEAK WAVES
DROPPING OUT OF CANADA ARE TOO LOW TO MENTION RIGHT NOW. TEMPS WILL
SLOWLY WARM THROUGH LATE WEEK.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON)
ISSUED AT 1232 PM CDT SUN JUL 27 2014
MVFR CIGS WILL GRADUALLY LIFT INTO VFR RANGE BY LATE AFTERNOON WITH
CLEARING THIS EVENING AS LOW PRESSURE EXITS THE AREA. REMAINDER OF
THE FORECAST PERIOD WILL BE VFR.
&&
.FGF WATCHES/WARNINGS/ADVISORIES...
ND...NONE.
MN...NONE.
&&
$$
UPDATE...GODON
SHORT TERM...JR
LONG TERM...JR/MAKOWSKI
AVIATION...VOELKER
AREA FORECAST DISCUSSION
NWS BISMARCK ND
1216 PM CDT SUN JUL 27 2014
.UPDATE...
ISSUED AT 1204 PM CDT SUN JUL 27 2014
PERSISTENT CLOUD COVER REMAINS OVER THE AREA IN NRLY FLOW IN THE
WAKE OF DEPARTING LOW OVER THE GREAT LAKES REGION. CURRENT
SATELLITE TRENDS ALONG WITH SHORT TERM GUIDANCE SUGGESTS THE
CLOUDS ARE HERE TO STAY THROUGH MOST OF THE DAY. WITH THAT...HAVE
ADJUSTED CLOUD COVER UP INTO THIS EVENING AND HAVE DROPPED HIGH
TEMPS A BIT. UPDATES HAVE BEEN SENT.
UPDATE ISSUED AT 925 AM CDT SUN JUL 27 2014
ONLY CHANGE FOR MORNING UPDATE IS TO UP CLOUD COVER A BIT. CURRENT
TRENDS ARE KEEPING CLOUD COVER AROUND LONGER THAN PREVIOUSLY
THOUGHT...THOUGH STILL EXPECT IT TO DECREASE SOME BY AFTERNOON.
UPDATES HAVE BEEN SENT.
UPDATE ISSUED AT 625 AM CDT SUN JUL 27 2014
INITIALIZED THE GRIDS WITH THE LOW CLOUD SATELLITE CHANNEL AND THAT
BEEFED UP THE CLOUD COVER A BIT ACROSS MOST OF THE WEST AND
CENTRAL. SATELLITE LOOPS SHOWING STRATO CU A LITTLE MORE PERVASIVE
THIS MORNING. THE TREND WILL STILL BE DECREASING CLOUDS BY THIS
AFTERNOON AS THE UPPER LOW LEAVES THE AREA.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 308 AM CDT SUN JUL 27 2014
LATEST WATER VAPOR IMAGERY SHOWS AN UPPER CLOSED LOW OVER NORTHERN
MINNESOTA WITH A COMPENSATING NORTHERLY TO NORTHWESTERLY FLOW INTO
NORTH DAKOTA. FOG/STRATUS LOOP AND SURFACE OBSERVATIONS SHOW SEVERAL
POCKETS OF BKN/OVC LOW CLOUDS CONTINUING TO MOVE FROM NORTHERN
NORTH DAKOTA INTO CENTRAL NORTH DAKOTA. PER HRRR CEILING
FORECAST...EXPECT THESE CLOUDS TO LINGER THROUGH MID MORNING THEN
LIFT INTO A FAIRLY LARGE SCT/BKN STRATOCUMULUS FIELD THROUGH THE
AFTERNOON. ENOUGH INSTABILITY WILL EXIST OVER THE FAR SOUTHERN
JAMES RIVER VALLEY/EASTERN LAMOURE AND DICKEY COUNTIES PER
GFS/ECMWF FOR AN ISOLATED AFTERNOON SHOWER OR THUNDERSHOWER. THE
REST OF WESTERN AND CENTRAL NORTH DAKOTA WILL BE DRY. 850MB TEMPS
GENERALLY THE SAME OR 1C COOLER OVER SATURDAYS. WITH CLOUDS
LINGERING MORE ACROSS THE NORTH AND EAST...HIGH TEMPERATURES WILL
ONLY REACH THE LOWER 70S. EXPECT HIGHS IN THE MID/UPPER 70S WEST
THROUGH SOUTH CENTRAL. FOR SUNDAY NIGHT...A SURFACE HIGH PRESSURE
WILL SPREAD ACROSS NORTH CENTRAL NORTH DAKOTA WITH A CLEAR SKY AND
COOL TEMPERATURES. OVERNIGHT LOWS WILL BE AROUND 50F.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 308 AM CDT SUN JUL 27 2014
THE MAIN FEATURE IN THE EXTENDED PERIOD WILL BE A BLOCKING
WEATHER PATTERN FEATURING A LONG WAVE TROUGH OVER THE EASTERN US
AND A RIDGE OVER THE WEST. THIS WILL LEAVE THE NORTHERN PLAINS
GENERALLY CUTOFF FROM GULF MOISTURE AND POPS THROUGH THE PERIOD ARE
LOW. ALTHOUGH NORTHWEST FLOW CAN OFTEN BRING SURPRISE CONVECTION AS
WEAK IMPULSES ARE INEVITABLE EMBEDDED IN THE NORTHWEST FLOW FOR
NOW WILL LEAVE THIS PERIOD DRY. FOR TEMPERATURES EXPECT A GRADUAL
MODERATING TREND FROM BELOW NORMAL TEMPERATURES MONDAY TO NEAR OR
ABOVE NORMAL BY THE WEEKEND.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON)
ISSUED AT 1204 PM CDT SUN JUL 27 2014
MVFR CIGS WILL REMAIN OVER CENTRAL AND WESTERN NORTH DAKOTA
THROUGH MUCH OF THE DAY BEFORE IMPROVING FROM WEST TO EAST LATE
THIS AFTERNOON INTO THIS EVENING.
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...JJS
SHORT TERM...KS
LONG TERM...WAA
AVIATION...JJS
AREA FORECAST DISCUSSION
NWS MEMPHIS TN
320 PM CDT SUN JUL 27 2014
.DISCUSSION...
AS OF 3PM...TEMPERATURES ARE CURRENTLY IN THE LOW TO MID 90S
ACROSS THE AREA WITH DEWPOINTS HOVERING IN THE MID 70S. COMBINED
VALUES ARE CONTRIBUTING TO HEAT INDICES OF 101 TO 108 DEGREES
ACROSS MUCH OF THE REGION. A DECK OF PREFRONTAL MID LEVEL CLOUDS
HAVE DEVELOPED ACROSS THE REGION KEEPING TEMPERATURES STEADY FOR
THE TIME BEING. A COUPLE OF SHOWERS AND A THUNDERSTORM HAVE JUST
POPPED UP ON RADAR IN NORTHEAST ARKANSAS AND ARE MOVING WESTWARD
AND INTO OUR FA. 18Z SURFACE ANALYSIS PLACES A COLD FRONT FROM
CENTRAL MICHIGAN...DOWN THROUGH INDIANA...AND BACK THROUGH
SOUTHERN ILLINOIS..AND INTO SOUTHERN MISSOURI.
SHORT TERM...TONIGHT THROUGH WEDNESDAY...
ATMOSPHERIC CAPPING SHOULD REMAIN IN PLACE ACROSS MUCH OF THE
OF THE FA FOR THE REST OF THIS AFTERNOON. THE AFOREMENTIONED
FRONT WILL BEGIN TO MOVE INTO THE NORTHERN PORTION OF THE FA
AROUND 00Z AND MOVE INTO THE MEMPHIS METRO BY 03Z OR SO. THERE
IS STILL A BIT OF UNCERTAINTY AS TO WHETHER THERE WILL BE STORM
INITIATION ACROSS AREAS SOUTH OF THE I-40 CORRIDOR AT ALL. LATEST
MODEL SOUNDINGS SUGGEST THAT THE CAP SHOULD ERODE AROUND 22Z
LEADING TO STORM INITIATION...BUT A MID LEVEL STRATUS DECK AND A
LACK OF A CU DECK SUGGEST OTHERWISE. BOTH THE NAM AND HRRR SHOW
THE FRONT COMING THROUGH MEMPHIS DRY AND A FEW STORMS POSSIBLY
FIRING UP OVER NORTH MISSISSIPPI AFTER 03Z. IT REALLY SEEMS THAT
WE MAY BE TOO FAR REMOVED THE UPPER LEVEL DYNAMICS TO SEE THE CAP
ERODE. NONETHELESS...ANY STORMS THAT DO INITIATE WILL BECOME
ROBUST AND LIKELY BECOME SEVERE WITH A THREAT OF DAMAGING
WINDS...LARGE HAIL...AND FLASH FLOODING. THE FRONT WILL PUSH
THROUGH THE ENTIRE MID-SOUTH BY TOMORROW MORNING.
BY MONDAY...COOL CANADIAN HIGH PRESSURE WILL BUILD IN BEHIND THE
FRONT AND NORTHWEST WINDS WILL USHER IN A MUCH DRIER AIRMASS. THIS
AIRMASS WILL REMAIN IN PLACE THROUGH AT LEAST THURSDAY. THIS WILL
LEAD TO FALL-LIKE CONDITIONS ACROSS THE REGION WITH HIGHS IN THE
LOW TO MID 80S WITH OVERNIGHT LOWS IN THE UPPER 50S TO LOWER 60S.
WEDNESDAY MORNING APPEARS TO BE THE COOLEST OF THE WEEK WITH LOWS
IN THE UPPER 50S ACROSS MUCH OF WEST TENNESSEE.
LONG TERM...WEDNESDAY NIGHT THROUGH NEXT WEEKEND...
MODEL GUIDANCE CONTINUES TO INDICATE THAT A BROAD TROUGH WILL
REMAIN OVER THE EASTERN HALF OF THE UNITED STATES THROUGH THE
WEEKEND KEEPING US IN NORTHWEST FLOW ALOFT. THIS WILL KEEP US IN A
BELOW NORMAL TEMPERATURE PATTERN WITH HIGHS MAINLY IN THE 80S. IN
ADDITION...A FEW UPPER LEVEL DISTURBANCES MAY ROTATE AROUND THE
RIDGE TO OUR WEST AND TRIGGER A FEW SHOWERS AND THUNDERSTORMS NEAR
OUR AREA. STILL TOO EARLY TO TELL IF ANY WILL MAKE IT THAT FAR
EAST...SO LEFT ANY MENTIONABLE RAIN OUT OF THE FORECAST FOR NOW.
AC3
&&
.AVIATION...
18Z TAFS
MAIN CONCERN IS AFTERNOON TSRA POTENTIAL. ATMOSPHERE WILL BE HIGHLY
UNSTABLE BUT PREDOMINATELY CAPPED TO DEEP CONVECTION DUE TO A WARM
LAYER OF AIR AROUND FL060. BEST CHANCE OF LOW LEVEL WIND CONVERGENCE
SUFFICIENT TO OVERCOME THE CAP APPEARS NEAR MKL AFTER 21Z. BASED
ON 12Z NAM MODEL BUFR SOUNDINGS...WHICH SHOWED A SLIGHTLY STRONGER CAP...
HAVE MAINTAINED VCTS AT MEM...BUT DIALED BACK THE START TIME TO 22Z
AND REDUCED CB COVERAGE.
GRADUAL /AROUND 2 HOUR/ VEERING OF THE WIND TO THE NORTHWEST WILL
OCCUR WITH A COLD FRONTAL PASSAGE THIS EVENING...WITH VFR PREVAILING
AREAWIDE IN THE DRIER POST FRONTAL AIRMASS.
PWB
&&
.MEG WATCHES/WARNINGS/ADVISORIES...
AR...HEAT ADVISORY UNTIL 6 PM CDT THIS EVENING FOR CRITTENDEN-LEE AR-
PHILLIPS-ST. FRANCIS.
MO...NONE.
MS...HEAT ADVISORY UNTIL 6 PM CDT THIS EVENING FOR ALCORN-BENTON MS-
CALHOUN-CHICKASAW-COAHOMA-DESOTO-ITAWAMBA-LAFAYETTE-LEE MS-
MARSHALL-MONROE-PANOLA-PONTOTOC-PRENTISS-QUITMAN-
TALLAHATCHIE-TATE-TIPPAH-TISHOMINGO-TUNICA-UNION-YALOBUSHA.
TN...HEAT ADVISORY UNTIL 6 PM CDT THIS EVENING FOR CHESTER-FAYETTE-
HARDEMAN-HARDIN-MCNAIRY-SHELBY.
&&
$$
AREA FORECAST DISCUSSION...UPDATED
NWS MEMPHIS TN
1234 PM CDT SUN JUL 27 2014
.UPDATE...
UPDATED FOR 18Z AVIATION DISCUSSION BELOW.
&&
.PREV DISCUSSION... /ISSUED 1013 AM CDT SUN JUL 27 2014/
UPDATE...MORNING UPDATE.
AS OF 10AM...TEMPERATURES ARE RUNNING ABOUT THE SAME AS YESTERDAY
AT THIS TIME WITH READINGS IN THE LOW TO MID 80S. A MID LEVEL BROKEN
STRATUS DECK RESIDES OVER THE MIDDLE THIRD OF THE FA...BUT SHOULD
BEGIN TO MIX OUT VERY SOON KEEPING TEMPERATURES ON TRACK TO TOP
OUT IN THE LOW TO MID 90S THIS AFTERNOON. CURRENT DEWPOINTS ARE IN
THE MID 70S...PUTTING MOST AREAS AT HEAT INDEX VALUES OF MID TO
UPPER 90S ALREADY. OPTED FOR A HEAT ADVISORY IN THE SOUTHERN TWO
THIRDS OF THE AREA...WHERE HEAT INDEX VALUES WILL MEET OR EXCEED
THE 105 DEGREE THRESHOLD. A COLD FRONT CURRENTLY EXTENDS FROM
SOUTHERN MI...DOWN THROUGH CENTRAL IL...AND INTO CENTRAL MO.
LATEST MODEL GUIDANCE INDICATES VERY LARGE INSTABILITY OVER MUCH
OF THE MID-SOUTH FOR THIS AFTERNOON WITH SBCAPE VALUES IN EXCESS
OF 4000 J/KG AND LI`S NEAR -10C. LATEST HRRR DEPICTS STORM
INITIATION JUST AHEAD OF THE FRONT IN THE 22Z-00Z TIME RANGE ALONG
A LINE FROM JONESBORO AR TO PARIS TN AND THEN MOVING SOUTHWARD
INTO THE MEMPHIS METRO AS A BROKEN LINE THROUGH SUNSET. ANY STORMS
THAT DO INITIATE WILL LIKELY GO SEVERE DUE TO THE AMOUNT OF PURE
INSTABILITY. THE PRIMARY HAZARDS STILL APPEAR TO BE DAMAGING WINDS
AND LARGE HAIL. UPDATED THE HWO TO INCLUDE A SLIGHT RISK OF SEVERE
THUNDERSTORMS OVER THE MISSOURI BOOTHEEL...ALL OF WEST TENNESSEE...AND
MOST OF NORTHEAST ARKANSAS.
ALL OTHER FORECASTED PARAMETERS ARE ON TRACK. NEW GRIDS AND ZONES
WILL BE AVAILABLE SOON.
AC3
PREV DISCUSSION... /ISSUED 404 AM CDT SUN JUL 27 2014/
DISCUSSION...
ITS A WARM MUGGY SUMMER NIGHT ACROSS THE MIDSOUTH. TEMPERATURES
REMAIN IN THE LOW 80S AT THE WARMEST LOCATIONS ACROSS THE REGION
INCLUDING THE MEMPHIS METRO AREA WITH THE REMAINDER OF THE REGION
IN THE MIDDLE TO UPPER 70S. MORNING LOWS WILL LIKELY BE IN THE
MIDDLE TO UPPER 70S. TODAY MIGHT BE THE WARMEST DAY WE HAVE SEEN
SO FAR THIS YEAR...AND LIKELY THE WARMEST DAY FOR THE NEXT WEEK OR
SO. AFTERNOON HIGHS WILL BE IN THE MIDDLE 90S. WITH HEAT INDICES
BETWEEN 100 AND 104 DEGREES...JUST BELOW HEAT ADVISORY CRITERIA.
GUIDANCE HAS BEEN RUNNING 2-4 DEGREES TOO WARM RECENTLY SO SHAVED
A COUPLE OF DEGREES OFF MOS GUIDANCE NUMBERS WHICH ARE IN THE
97-98 DEGREE RANGE FOR MUCH OF THE MIDSOUTH. AFTERNOON CLOUD COVER
AND SCATTERED SHOWERS AND THUNDERSTORMS WILL ALSO HELP TO LIMIT
AFTERNOON HEATING. THE STORM PREDICTION CENTER HAS PLACED PORTIONS
OF WEST TENNESSEE...GENERALLY NORTH OF INTERSTATE 40 UNDER A
SLIGHT RISK FOR SEVERE THUNDERSTORMS THIS AFTERNOON INTO TONIGHT.
A COLD FRONT WILL MOVE INTO THE AREA THIS EVENING HELPING TO FOCUS
LIFT ACROSS THE REGION. DEW POINTS ARE IN THE MIDDLE 70S. AS
TEMPERATURES WARM...AHEAD OF THE COLD FRONT...AFTERNOON CAPE
VALUES WILL CLIMB IN EXCESS OF 3500 J/KG WITH LI`S BELOW -9C. STORMS
WILL LIKELY TURN SEVERE VERY QUICKLY AS THEY DEVELOP. THE GREATEST
THREAT FOR SEVERE WEATHER WILL BE TO OUR EAST WHERE A MID LEVEL
JET WILL ENHANCE STORMS...BUT AREAS AS FAR WEST AS THE MISSOURI
BOOTHEEL AND JACKSON TENNESSEE COULD SEE SEVERE STORMS. DAMAGING
WIND IS THE PRIMARY THREAT...BUT LARGE HAIL AND LOCALIZED FLOODING
ARE ALSO POSSIBLE. THREE HOUR FLASH FLOOD GUIDANCE IS GENERALLY
2.5 TO 3.5 INCHES ACROSS THE AREA. HPC QPF GUIDANCE IS ONLY ABOUT
ONE QUARTER OF AN INCH OR LESS...SO WIDESPREAD FLOODING PROBLEMS
ARE NOT EXPECTED. HOWEVER WITH GUIDANCE...PW VALUES IN EXCESS OF
TWO INCHES...LOCALLY HEAVY RAINFALL IS LIKELY. STORMS WILL LIKELY
CONTINUE OVERNIGHT...BUT COVERAGE AND INTENSITY SHOULD SLOWLY
DIMINISH.
MONDAY...COOLER CONDITIONS WILL RETURN TO THE MIDSOUTH. MUCH LIKE
WE HAVE SEEN FOR MOST OF THE SUMMER SO FAR. HIGHS MONDAY WILL BE
5-8 DEGREES BELOW NORMAL...IN THE LOW TO MIDDLE 80S ACROSS MOST OF
THE AREA. MORNING LOWS MIDWEEK MAY FALL INTO THE MID TO UPPER 50S
AT THE COOLEST LOCATIONS WITH MOST AREAS IN THE LOWER 60S.
TEMPERATURES WILL TREND A DEGREE OR TWO WARMER EACH DAY DURING THE
WORK WEEK...BUT REMAIN BELOW NORMAL. BY FRIDAY HIGHS MAY APPROACH
90 DEGREES AT THE WARMEST LOCATIONS. ANOTHER COLD FRONT LOOKS
POSSIBLE FRIDAY INTO NEXT WEEKEND. GUIDANCE POPS REMAIN PRETTY LOW
DUE TO LACK OF MOISTURE. WILL KEEP CONDITIONS DRY FOR NOW...BUT
WOULDN`T BE SURPRISED TO SEE A FEW SHOWERS AROUND IN UPCOMING
MODEL RUNS.
30
&&
.AVIATION...
18Z TAFS
MAIN CONCERN IS AFTERNOON TSRA POTENTIAL. ATMOSPHERE WILL BE HIGHLY
UNSTABLE BUT PREDOMINATELY CAPPED TO DEEP CONVECTION DUE TO A WARM
LAYER OF AIR AROUND FL060. BEST CHANCE OF LOW LEVEL WIND CONVERGENCE
SUFFICIENT TO OVERCOME THE CAP APPEARS NEAR MKL AFTER 21Z. BASED
ON 12Z NAM MODEL BUFR SOUNDINGS...WHICH SHOWED A SLIGHTLY STRONGER CAP...
HAVE MAINTAINED VCTS AT MEM...BUT DIALED BACK THE START TIME TO 22Z
AND REDUCED CB COVERAGE.
GRADUAL /AROUND 2 HOUR/ VEERING OF THE WIND TO THE NORTHWEST WILL
OCCUR WITH A COLD FRONTAL PASSAGE THIS EVENING...WITH VFR PREVAILING
AREAWIDE IN THE DRIER POST FRONTAL AIRMASS.
PWB
&&
.MEG WATCHES/WARNINGS/ADVISORIES...
AR...HEAT ADVISORY UNTIL 6 PM CDT THIS EVENING FOR CRITTENDEN-LEE AR-
PHILLIPS-ST. FRANCIS.
MO...NONE.
MS...HEAT ADVISORY UNTIL 6 PM CDT THIS EVENING FOR ALCORN-BENTON MS-
CALHOUN-CHICKASAW-COAHOMA-DESOTO-ITAWAMBA-LAFAYETTE-LEE MS-
MARSHALL-MONROE-PANOLA-PONTOTOC-PRENTISS-QUITMAN-
TALLAHATCHIE-TATE-TIPPAH-TISHOMINGO-TUNICA-UNION-YALOBUSHA.
TN...HEAT ADVISORY UNTIL 6 PM CDT THIS EVENING FOR CHESTER-FAYETTE-
HARDEMAN-HARDIN-MCNAIRY-SHELBY.
&&
$$
AREA FORECAST DISCUSSION
NWS HOUSTON/GALVESTON TX
1138 AM CDT SUN JUL 27 2014
.DISCUSSION...
SEE 18Z AVIATION DISCUSSION.
&&
.AVIATION...
PW VALUES HAVE DROPPED FROM YESTERDAY AND CU FIELD CONSIDERABLY
LESS. FCST SOUNDINGS SHOW A DRIER COLUMN WITH HIGHER CONVECTIVE
TEMPS. ONLY THE HRRR IS SHOWING PCPN ON THE SEA BREEZE LATER THIS
AFTN. COVERAGE LOOKS TOO SLIGHT TO MENTION IN AREA TAFS SO WILL
REMOVE MENTION OF VCSH. VFR CONDS EXPECTED OVERNIGHT WITH THE
EXCEPTION OF SOME PATCHY FOG AROUND SUNRISE AT KCXO AND KLBX. 43
&&
.PREV DISCUSSION... /ISSUED 923 AM CDT SUN JUL 27 2014/
UPDATE...
OTHER THAN ISOLATED GULF SHOWERS...IT HAS BEEN A QUIET MORNING
PRECIPITATION-WISE. UPPER AIR ANALYSIS DEPICTS A DRY AND HOT DAY
AS 5H RIDGING HAS NOW ENVELOPED THE REGION. LOWER LAYERS ARE
ADVECTING IN A DRIER AIR MASS UPON WARMER SOUTHWESTERLIES WHILE
UPPER LAYER FLOW IS DRAWING IN A DRIER NORTHEASTERLY AIR MASS.
THIS TEAMING OF SUBSIDENCE AND DRY AIR WILL EQUATE TO A MOSTLY TO
PARTLY SUNNY DAY AS MANY INTERIOR TEMPERATURES REACH THE MIDDLE
90S...AROUND 90F AT COAST...WITH AN EARLY DAY SOUTHWEST BREEZE
BACKING SOUTHERLY AS INLAND TEMPERATURES WARM PAST 90F. 31
PREV DISCUSSION... /ISSUED 441 AM CDT SUN JUL 27 2014/
DISCUSSION...
SFC ANALYSIS HAS COLD FRONT PUSHING THROUGH KS INTO TX/OK PANHANDLES
WITH SOUTHERLY WINDS AHEAD OF IT BRINGING GULF MOISTURE INTO THE
PLAINS. BASED OFF 00Z SOUNDINGS AND GOES SOUNDER DATA...PRECIP
WATER VALUES HAVE DROPPED ALONG THE COAST WITH BEST MOISTURE ALONG
THE N GULF. THE 00Z 500MB ANALYSIS HAS BROAD RIDGE OVER THE S
PLAINS INTO THE 4 CORNERS REGION. RIDGE DID NOT STOP A FEW
SHOWERS/STORMS FROM FORMING YESTERDAY SO IT IS REASONABLE TO
EXPECT A FEW ISO STORMS AGAIN TODAY. BUT IT LOOKS LIKE THERE WILL
BE LESS MOISTURE TO WORK WITH SO WILL KEEP POPS IN THE 10-15
PERCENT RANGE AND MENTION ISO STORMS. MAX TEMPS WILL BE BACK INTO
THE 95-97F RANGE WITH HEAT INDEX VALUES AROUND 103-105. OVERALL
JUST YOUR TYPICAL HOT CONDITIONS EXPECTED FOR THE END OF JULY.
WATER VAPOR IMAGERY ALSO SHOWS UPPER LOW OVER MINN WITH A STRONG
JET STREAK OVER THE C PLAINS INTO THE MIDWEST. MODELS HAVE THIS
UPPER LOW AND JET STREAK DIGGING INTO THE GREAT LAKES/OHIO RIVER
VALLEY TODAY/TONIGHT. THIS ALLOWS THE RIDGE TO BUILD OVER THE
ROCKIES BUT NOT REALLY WEAKEN MUCH OVER TX. THE RIDGE FINALLY
WEAKENS MON INTO TUE. THIS ALSO CORRESPONDS TO WHEN A COLD FRONT
AT THE SURFACE MOVES INTO TX MON NIGHT INTO TUE. THE FRONT THEN
PUSHES INTO SE TX TUE AND STALLS MAINLY FROM A NW TO SE DIRECTION.
STILL SOME UNCERTAINTY AS TO THE EXACT POSITION THE FRONT STALLS.
REGARDLESS THE FRONT WILL BE A FOCUS FOR THUNDERSTORM DEVELOPMENT
TUE THROUGH THUR. RIGHT NOW 20/30 POPS LOOK ON TRACK WITH
BASICALLY SCATTERED THUNDERSTORM ACTIVITY. PRECIP WATER VALUES
WILL BE AROUND 2 INCHES ALONG AND SOUTH OF THE FRONT SO EXPECT
SOME STORMS TO PRODUCE BRIEF HEAVY RAINFALL.
THE TROUGH CONTINUES TO BROADEN INTO THE PLAINS FROM THE GREAT
LAKES INTO THUR. GFS/ECMWF SHOW A STRONG SHORTWAVE TROUGH MOVING
ACROSS THE S PLAINS WED INTO THUR. LOOKS LIKE ANOTHER FAVORABLE
SET UP FOR HEAVY RAINFALL BUT PLACEMENT OF CONVECTIVE SYSTEM COULD
BE MORE OVER N TX BUT STILL SOMETHING TO MONITOR. RAIN CHANCES OF
30 PERCENT LOOKS ON TRACK FOR THUR BUT COULD SEE HIGHER CHANCES
FOR SOME OF THE NORTHERN COUNTIES IN THE FORECAST AREA.
BROAD TROUGHING CONTINUES INTO NEXT WEEKEND SO EXPECT THERE TO BE
SLIGHTLY COOLER TEMPS FOR THE END OF THE WEEK. WILL ALSO NEED TO
HOLD ONTO AT LEAST 20 POPS FOR THUNDERSTORM ACTIVITY DEVELOPING
WITH DAYTIME HEATING AND DEEP MOISTURE IN PLACE. UPPER LEVEL RIDGE
WILL BE OVER THE ROCKIES SO DO NOT SEE ANY SUBSIDENCE IN THE
ATMOSPHERE TO INHIBIT THUNDERSTORM DEVELOPMENT. 39
MARINE...
LIGHT TO MODERATE SOUTH TO SOUTHWEST WINDS WILL PERSIST THROUGH THE
FIRST HALF OF NEXT WEEK. WINDS WILL EASE SLIGHTLY BY MID WEEK AS A
COLD FRONT MOVES INTO SOUTHEAST TEXAS. 38
&&
.PRELIMINARY POINT TEMPS/POPS...
COLLEGE STATION (CLL) 96 76 96 76 93 / 10 10 20 30 30
HOUSTON (IAH) 96 77 95 77 93 / 10 10 10 30 30
GALVESTON (GLS) 92 81 91 81 90 / 10 10 10 20 30
&&
.HGX WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
GM...NONE.
&&
$$
DISCUSSION...31
AVIATION/MARINE...43
FOR FREQUENTLY ASKED QUESTIONS ABOUT THE AREA FORECAST DISCUSSION
VISIT...
HTTP://WEATHER.GOV/SALTLAKECITY/GENERAL/AFD_FAQS.PHP (ALL LOWER CASE)
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
157 PM CDT SUN JUL 27 2014
.SHORT TERM...(TONIGHT THROUGH MONDAY NIGHT)
ISSUED AT 157 PM CDT SUN JUL 27 2014
WATER VAPOR SATELLITE AND RAP 500MB ANALYSIS THIS AFTERNOON SHOWING
MID LEVEL LOW OVER EAST CENTRAL WI. RADAR/VIS SATELLITE SHOWING
QUITE AN EXTENSIVE FIELD OF CUMULUS/CUMULONIMBUS AND SCATTERED
SHOWER/ISOLATED THUNDERSTORM ACTIVITY ACROSS THE ARX FORECAST AREA
IN THE CYCLONIC/STEEP LAPSE RATE ENVIRONMENT. TEMPERATURES THIS
AFTERNOON RANGED FROM THE UPPER 60S ACROSS NORTH CENTRAL WI...TO THE
MIDDLE AND UPPER 70S ALONG AND SOUTH OF I-90.
LOOK FOR A RAPID DISSIPATION THIS EVENING IN SHOWER ACTIVITY WITH
LOSS OF SURFACE HEATING AND THEN A FAIRLY RAPID CLEARING CLOUD TREND
AS THE MID LEVEL LOW MOVES OFF INTO THE GREAT LAKE REGION.
COOLER/DRIER AIRMASS ASSOCIATED WITH HIGH PRESSURE OVER THE NORTHERN
PLAINS WILL BE WORKING INTO THE AREA TONIGHT. THIS WILL ALLOW
TEMPERATURES TO FALL INTO THE UPPER 40S IN THE SANDY/CRANBERRY BOG
COUNTRY OF CENTRAL/NORTH CENTRAL WI...AND IN THE LOWER/MIDDLE 50S
ELSEWHERE.
SURFACE HIGH PRESSURE WILL CONTINUE BUILDING INTO THE AREA ON MONDAY
FOR DRY AND COOLER THEN NORMAL CONDITIONS. LINGERING CYCLONIC FLOW
ALOFT WILL ALLOW FOR A BUILD-UP IN DAYTIME FAIR WEATHER
CUMULUS...BUT MOSTLY SUNNY CONDITIONS OVERALL SHOULD RESULT. PLAN ON
HIGHS IN THE LOW-MID 70S...OR SOME 6-8 DEGREES BELOW NORMAL FOR THIS
TIME OF YEAR. MOSTLY CLEAR AND COOL CONDITIONS WILL BE SEEN MONDAY
NIGHT AS WELL WITH LOWS BOTTOMING OUT IN THE UPPER 40S TO MIDDLE 50S
ONCE AGAIN.
.LONG TERM...(TUESDAY THROUGH SUNDAY)
ISSUED AT 157 PM CDT SUN JUL 27 2014
MODELS IN GOOD AGREEMENT IN BRINGING A MID-LEVEL/SURFACE TROUGH
THROUGH THE REGION ON TUESDAY IN BROAD CYCLONIC FLOW ALOFT. THIS
WILL PRODUCE THE LIKELIHOOD OF SCATTERED SHOWER AND ISOLATED
THUNDERSTORMS GIVEN THE FORCING FROM THE TROUGH AND COMBINATION OF
COOL CYCLONIC FLOW ALOFT/DAYTIME HEATING AND STEEPENING LOW-MID LEVEL
LAPSE RATES. OTHERWISE ANOTHER COOLER THAN NORMAL DAY ON TAP WITH
HIGHS TOPPING OFF IN THE 70S.
DEEP LONG WAVE TROUGH WILL SET UP CAMP OVER THE UPPER MISSISSIPPI
RIVER VALLEY REGION/EASTERN CONUS THROUGH THE REST OF THE PERIOD. AS
A RESULT...LOOKS TO REMAIN COOLER THAN NORMAL...WITH TEMPERATURES
CLOSER TO EARLY SEPTEMBER NORMALS. SEVERAL WEAK EMBEDDED TROUGHS
WITHIN THE LONG WAVE TROUGH WILL ROTATE THROUGH THE REGION FOR
PERIODIC/MAINLY DAYTIME SHOWER AND ISOLATED THUNDERSTORM CHANCES.
PLAN ON HIGHS IN THE 70S WITH LOWS IN THE 50S.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON)
ISSUED AT 1244 PM CDT SUN JUL 27 2014
UPPER SYSTEM DROPPING SOUTHEAST ACROSS WI AT MID-DAY WITH EXTENSIVE
WRAP AROUND CLOUD AND SHOWER ACTIVITY. AS THE LOW PULLS OFF TO THE
EAST AND BEST LIFT EXITS ALONG WITH IT...ANTICIPATE SOME DOWNWARD
MOTIONS TO HELP FLATTEN AND EVENTUALLY THIN/DISSIPATE THE CLOUD
COVER. MODEL MOS GUIDANCE VERY AGGRESSIVE WITH THIS TREND...BUT AM
LEARY OF THIS GIVEN THE AMOUNT OF MOISTURE REMAINING IN THE BOUNDARY
LAYER. PLAYED IT A BIT MORE PESSIMISTIC FOR THE 18Z TAF ISSUANCE.
DID GO WITH A PERIOD OF SCT CLOUD COVER...BUT ONCE DIURNAL HEATING
BEGINS AGAIN TOMORROW...WENT BACK TO BKN.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...DAS
LONG TERM...DAS
AVIATION...WELVAERT