Forecast Discussions mentioning any of
"HRRR" "RAP" "RR" "RUC13" "RUC" received at GSD on 08/27/14
AREA FORECAST DISCUSSION
NWS FLAGSTAFF AZ
845 PM MST TUE AUG 25 2014
.SYNOPSIS...
A LOW PRESSURE TROUGH WILL CONTINUE TO BRING NUMEROUS SHOWERS AND
THUNDERSTORMS EAST CENTRAL ARIZONA THIS EVENING. STORMS WILL
DECREASE FROM THE WEST TO EAST OVERNIGHT. SCATTERED STORMS EXPECTED
AGAIN ON WEDNESDAY AS THE LOW PRESSURE AREA PULLS AWAY FROM THE
AREA. A DRY WEST TO NORTHWEST FLOW WILL BRING DRY CONDITIONS AND
SLIGHTLY WARMER HIGH TEMPERATURES FROM THURSDAY THROUGH EARLY NEXT
WEEK.
&&
.DISCUSSION...IT WAS AN ACTIVE LATE AFTERNOON AND EARLY EVENING WITH
SCATTERED THUNDERSTORMS AND ISOLATED HEAVY RAIN. MOST ACTIVITY IS
NOW IN EASTERN GILA...SOUTHERN NAVAJO AND SOUTHERN APACHE COUNTY.
THIS ACTIVITY WILL CONTINUE TO PUSH EASTWARD THIS EVENING. HAVE
UPDATED THE FORECAST TO DROP POPS AND FLASH FLOOD WATCH IN THE
WESTERN ZONES.
&&
.PREV DISCUSSION /320 PM MST/...
RECENT HRRR RUNS CONSISTENT WITH DOWNSWING IN ACTIVITY FROM SOUTHWEST
TO NORTHEAST ACROSS THE CWA THIS EVENING AS DRY AIR AND SUBSIDENCE
WORKS IN FROM THE WEST...WITH PRIMARY IMPACTS LIMITED TO NE AZ AFTER
06Z. CURRENT TRENDS SUPPORT THESE FORECASTS.
ON WEDNESDAY...LINGERING BOUNDARY LAYER MOISTURE WILL BE ADEQUATE FOR
SCATTERED SHOWERS AND THUNDERSTORMS TO REDEVELOP...MOST NUMEROUS OVER
AND NORTHEAST OF THE MOGOLLON RIM.
THURSDAY THROUGH THE WEEKEND...MODELS CONTINUE TO BE CONSISTENT WITH
STRONG RIDGING OVER THE SOUTHWEST...BRINGING FAIR AND WARM WEATHER
TO THE NORTHLAND THROUGH THE WEEKEND...AND INTO EARLY NEXT WEEK.
&&
.AVIATION...
FOR THE 06Z PACKAGE...ISOLD-SCT SHRA/TSRA WILL PERSIST EAST OF A
KPAN-KSJN. STORMS WILL DECREASE FROM THE SOUTHWEST TO NORTHEAST
THROUGH 10Z. ISOLD TSRA OVER HIGHER TERRAIN AFTER 18-02Z.
AVIATION DISCUSSION NOT UPDATED FOR AMENDMENTS.
&&
.FGZ WATCHES/WARNINGS/ADVISORIES...
FLASH FLOOD WATCH UNTIL 1100 PM MST FOR AZZ013-014-016>018.
&&
$$
PUBLIC.........MAS/BAK
AVIATION.......MAS
FOR NORTHERN ARIZONA WEATHER INFORMATION VISIT
WEATHER.GOV/FLAGSTAFF
AREA FORECAST DISCUSSION
NWS PHOENIX AZ
605 PM MST TUE AUG 26 2014
.UPDATE...EARLY EVENING DISCUSSION UPDATE AND REMOVAL OF THE FLASH
FLOOD WATCH HEADLINE...
&&
.SYNOPSIS...
AFTER TODAY...STORM ACTIVITY WILL BEGIN TO TREND DOWNWARD OVER
ARIZONA AS A LOW PRESSURE SYSTEM STARTS TO SHIFT EASTWARD.
MUCH DRIER AIR WILL MOVE INTO THE REGION FROM THE NORTH WITH DRY
CONDITIONS EXPECTED THURSDAY THROUGH TUESDAY.
&&
.DISCUSSION...
DRY AIR INTRUSION FROM THE WEST TO SOUTHWEST NOTED CLEARLY ON
EVENING IR/WV IMAGERY ACROSS SOUTHWESTERN AND SOUTH-CENTRAL AZ THIS
EVENING. WIDELY SCATTERED ACTIVITY CONTINUES TO PERCOLATE OVER
PORTIONS OF THE LOWER DESERT LOCALES...WITH THE BEST LOOKING
ACTIVITY EXPANDING IN COVERAGE ACROSS SOUTHERN GILA COUNTY. EARLIER
STORM ACTIVITY OVER LA PAZ COUNTY HAS GRADUALLY DIMINISHED IN
COVERAGE AND INTENSITY OVER THE LAST HOUR...WITH POP-UP SHOWERS
PULSING IN AREAS WHERE SPC MESOANALYSIS DEPICT 1000-1500 J/KG
POCKETS OF SBCAPE. UPPER JET STREAK ANALYZED RUNNING SW-NE RIGHT
OVER CENTRAL AZ...WITH JET ENTRANCE ENERGY HELPING ORGANIZE THE
ACTIVITY OVER SOUTHERN GILA COUNTY.
WITH DRYING...LOSS OF DIURNAL HEATING AND THE DEPARTURE OF THE JET
ENERGY TO OUR NORTHEAST...WILL LOOK FOR ONLY ISOLATED STORM COVERAGE
TO CONTINUE INTO THE EVENING HOURS. 00Z KPSR BALLOON STILL PRESENTS
WITH SOME MINIMAL CAPE...NEAR 900 J/KG. COULD CONCEIVABLY SEE STORM
ACTIVITY RIGHT UP TO THE PERIPHERY OF THE PHX METRO BUT WIDESPREAD
ORGANIZED ACTIVITY NOT LOOKING VERY LIKELY ATTM. THE EARLIER FLASH
FLOOD WATCH WAS ALLOWED TO EXPIRE AT 5 PM MST. THE CONCERN FOR
WIDESPREAD FLASH FLOODING IS NOT AS GREAT...ESPECIALLY AS DRIER AIR
CONTINUES TO WORK INTO THE REGION. ANY ADDITIONAL STORM ACTIVITY TO
DEVELOP IN THE EVENING COULD PRODUCE BRIEF MODERATE TO HEAVY
RAINFALL...ALONG THE WITH COMBINATION THREAT FOR STRONG GUSTY
WINDS. THERE REMAINS A FAR AMOUNT OF ACTIVITY MOVING ACROSS
SOUTHEAST AZ THAT COULD SEND OUTFLOW BOUNDARIES INTO THE AREA. IN
ADDITION...SEVERAL OUTFLOW BOUNDARIES HAVE BEEN TRACKING ACROSS THE
PHX METRO FROM THE NORTH...WITH OBSERVED GUSTS NEAR 30 MPH WITH THE
BEST LOOKING OUTFLOW NEAR MESA FALCON-FIELD AT TIME OF THIS WRITING.
MAY NEED TO DEAL WITH LOCALIZED BLOWING DUST IS OUTFLOWS REMAIN
TOGETHER AND TRAVEL LONG ENOUGH INTO THE OUR FORECAST AREA FROM THE
SOUTHEAST.
&&
.PREVIOUS DISCUSSION /ISSUED AT 145 PM MST/PDT...
A STRONG STORM PASSED THROUGH PARKER AROUND MIDDAY AND VERY STRONG
STORMS DEVELOPED JUST NORTH OF LA PAZ COUNTY SHORTLY THEREAFTER.
GOOD CAPE AIDED BY DYNAMICAL FORCING...ASSOCIATED WITH AN UPPER
LOW...CAME TOGETHER. MAIN DYNAMICAL FEATURE IS A JET CENTERED OVER
NORTHWEST ARIZONA. WITH SOME LIFT DRIVEN BY RIGHT ENTRANCE REGION
DYNAMICS STILL TO AFFECT AN AREA STRETCHING FROM PARKER TO
WICKENBURG THIS AFTERNOON...THE FLASH FLOOD WATCH WAS EXPANDED
THERE. THE WATCH WAS ALSO EXPANDED IN TIME TO END AT 5 PM AS HI RES
MODEL GUIDANCE INDICATES STORM ACTIVITY CONTINUING PAST 2
PM...MAINLY OVER SOUTHERN GILA COUNTY. ANOTHER FACTOR IN ADDITION TO
THE SLOWLY DEPARTING JET OVER NORTHWEST ARIZONA IS ANOTHER JET
STREAK ALREADY MOVING ACROSS SOUTHERN ARIZONA PER MODELS. HRRR WAS
SLOW TO CATCH ON TO LA PAZ AND MOHAVE COUNTY ACTIVITY AND OTHER HI
RES MODELS HAVE PRETTY MUCH MISSED IT. HOWEVER...LATEST HRRR SHOWS
ACTIVITY LINGERING OVER LA PAZ COUNTY THROUGH 23Z AND DECREASING
AFTER THAT. IT ALSO SHOWS NORTHERNMOST MARICOPA COUNTY AND GILA
COUNTY BEING ACTIVE WITH MORE SPOTTY ACTIVITY OVER PHOENIX AREA AND
PINAL COUNTY. STORMS WILL NOT ONLY HAVE THE CAPABILITY OF PRODUCING
HEAVY RAIN BUT THERE IS ENOUGH CAPE AND SHEAR...MAINLY WEST OF
PHOENIX...TO BE CONCERNED ABOUT SEVERE POTENTIAL. DYNAMICAL FORCING
SHIFTS NORTHEASTWARD TONIGHT. THIS COMBINED WITH LOSS OF SURFACE
HEATING WILL MEAN A DOWN TREND FOR STORM CHANCES TONIGHT.
WITH THE PASSAGE OF THE TROUGH AXIS WEDNESDAY MORNING...STRONG
SYNOPTIC SUBSIDENCE AND DRYING OF THE ENTIRE COLUMN WILL SURGE
SOUTHEAST THROUGHOUT THE ENTIRE FORECAST AREA. THOUGH SOME RESIDUAL
MOISTURE MAY LINGER IN THE EASTERN CWA WITH SFC-H7 MIXING RATIOS
HOLDING NEAR 11 G/KG...NOTABLE WARMING ALOFT WILL SEVERELY LIMIT
INSTABILITY AND HAVE RELEGATED SOME MODEST SLIGHT CHANCE POPS TO
HIGHER TERRAIN LOCATIONS. OTHERWISE...SEASONABLY STRONG RIDGING WILL
TAKE HOLD OVER THE LOS ANGELES BASIN WITH H5 HEIGHTS AROUND
594DM...AND DOWNSTREAM NWLY FLOW COMPLETELY SCOURING MOISTURE FAR
AWAY FROM THE LOCAL REGION. ONLY ADDING INSULT TO INJURY...A STRONG
WLY JET CORE WILL DESCEND INTO THE GREAT BASIN BY THE END OF THE
WEEKEND...FURTHER REINFORCING THE WESTERLY FLOW LOCALLY (THE
ANTITHESIS OF THE NORTH AMERICAN MONSOON SEASON FLOW) AND KEEPING
MOISTURE WELL REMOVED FROM THE AREA. GIVEN THE EXCELLENT MODEL
AGREEMENT OF THIS PATTERN MORE REMINISCENT OF LATE
SEPTEMBER...FORECAST CONFIDENCE IS VERY HIGH FOR THURSDAY AND BEYOND
OF COMPLETELY DRY WEATHER AND HIGH TEMPERATURES NEAR TO SLIGHTLY
ABOVE AVERAGE.
&&
.AVIATION...
SOUTH-CENTRAL ARIZONA INCLUDING KPHX...KIWA...AND KSDL...
WIDELY SCATTERED STORM COVERAGE WILL PERSIST ON THE PERIPHERY OF THE
PHX METRO AND PERIODICALLY IMPACT THE TRACON GATES...BUT CONFIDENCE
IS LOW OF ANY ORGANIZED ACTIVITY FOR THE TERMINALS. WEAK ACTIVITY
OVER NW PINAL COULD CLIP KIWA...SO ADDED VCSH...BUT RADAR RETURNS
ARE QUICKLY LOOSING ANY PUNCH AS THE APPROACH THE TERMINAL. OUTFLOW
BOUNDARIES ALREADY OBSERVED MOVING IN FROM THE NORTH...WHICH COULD
BRIEFING TRANSITION WINDS AROUND AT THE TERMINALS...IF THEY COULD
OVERCOME THE STRONGER AND DRY WEST FLOW ALREADY IN PLACE ACROSS THE
REGION. ADDITIONAL OUTFLOW ACTIVITY COULD TRANSITION INTO THE AREA
FROM THE SOUTHEAST...WITH THE POSSIBILITY OF SOME VSBY REDUCING
DUST...BUT WILL CONTINUE MONITOR THE SITUATION BEFORE INTRODUCING
ANYTHING MVFR VSBYS. CONFIDENCE REMAINS LOW TO INCLUDE THUNDER IN
THE TAFS...WILL SIMPLY CARRY SCT-BKN CUMULUS DECKS MAINLY FROM
7-10K FEET. OTHERWISE EXPECT CLEARING BY EARLY OR MID EVENING AS A
DRIER MORE STABLE WESTERLY FLOW ALOFT MOVES INTO THE AREA.
SOUTHWEST ARIZONA AND SOUTHEAST CALIFORNIA INCLUDING KIPL AND KBLH...
NO SIGNIFICANT AVIATION IMPACTS EXPECTED THIS AFTERNOON OR
EVENING...AS THE UPPER LOW TO OUR NORTH SHIFTS OFF TOWARDS THE EAST
AND A DRIER WESTERLY FLOW ALOFT MOVES INTO THE WESTERN DESERTS. BY
EARLY EVENING SKIES WILL BECOME CLEAR OR MOSTLY CLEAR...AND WINDS
WILL DECREASE TO MOSTLY AOB 12KT....FAVORING THE SOUTHWEST OR WEST.
AVIATION DISCUSSION NOT UPDATED FOR AMENDED TAFS.
&&
.FIRE WEATHER...
FRIDAY THROUGH TUESDAY...
STRONG HIGH PRESSURE ALOFT WILL CONTINUE ACROSS SOUTHEAST CALIFORNIA
AND SOUTHERN ARIZONA FRIDAY INTO THE WEEKEND...KEEPING A DRY
NORTHWEST FLOW ACROSS THE AREA AND LEADING TO ABOVE NORMAL HIGH
TEMPERATURES. MINIMUM HUMIDITIES WILL BE ON THE LOW SIDE RANGING
MOSTLY FROM 10 TO 15 PERCENT ON FRIDAY AND SATURDAY. FOR SUNDAY INTO
EARLY NEXT WEEK...LOW PRESSURE ALOFT ACROSS THE PACIFIC NORTHWEST
WILL GRADUALLY STRENGTHEN SOUTHWARD LEADING TO INCREASING SOUTHWEST
OR WEST FLOW ALOFT. HIGH TEMPERATURES WILL SLOWLY FALL OFF TO BELOW
NORMAL VALUES BY NEXT TUESDAY. MINIMUM HUMIDITIES WILL STEADILY RISE
SUNDAY THROUGH TUESDAY WITH MANY DESERT LOCALES CLIMBING ABOVE 20
PERCENT. FAIR OVERNIGHT RECOVERIES FRIDAY NIGHT WILL GRADUALLY
INCREASE...BECOMING GOOD OR EXCELLENT BY EARLY NEXT WEEK. STRONG
WINDS ARE NOT EXPECTED DURING THE FIVE DAY PERIOD...HOWEVER LOCALLY
BREEZY CONDITIONS ARE POSSIBLE OVER THE WEEKEND WITH WINDS FAVORING
THE SOUTH TO SOUTHWEST DURING THE AFTERNOON AND EARLY EVENING HOURS.
&&
.PSR WATCHES/WARNINGS/ADVISORIES...
AZ...NONE.
CA...NONE.
&&
$$
VISIT US ON FACEBOOK...TWITTER...AND AT WEATHER.GOV/PHOENIX
DISCUSSION...NOLTE
PREVIOUS DISCUSSION...AJ/MO
AVIATION...NOLTE/CB
FIRE WEATHER...CB
AREA FORECAST DISCUSSION
NWS GRAND JUNCTION CO
938 PM MDT TUE AUG 26 2014
.UPDATE...
ISSUED AT 938 PM MDT TUE AUG 26 2014
SWRN UTAH CONVECTION MOVES INTO SERN UTAH LATER THIS EVENING...BUT
WILL BE ENCOUNTERING A MORE STABLE REGIME. SURFACE TEMPS HAVE
COOLED SIGNIFICANTLY WITH READINGS IN THE UPPER 50S TO MID 60S.
SPC MESOANALYSIS ALSO SHOW OUR AIR MASS HAVE LESS INSTABILITY PER
MLCAPE VALUES. STRONG STORMS OVER SWRN UTAH WILL HAVE WEAKENED
SIGNIFICANTLY ONCE THIS ACTIVITY REACHES SERN UTAH. THUS THE
FLASH FLOOD WATCH WAS CANCELLED EARLIER THIS EVENING.
SHOWERS WITH EMBEDDED STORMS HAVE NOT ENDED AS A VORTICITY LOBE
ROTATES AROUND THE ANOMALOUS CLOSED LOW ALONG THE NEVADA/UTAH
BORDER. THE BAND OF MOISTURE OVER THE FOUR CORNERS GETS LIFTED
NORTHWARD AND WRAPS AROUND THE UPPER LOW...EXPANDING IN THE
PROCESS. THIS WILL RESULT IN WIDESPREAD SHOWERS ACROSS NE UTAH AND
THE NRN 2/3RDS WRN COLORADO. POTENTIAL EXISTS FOR SIGNIFICANT PCPN
IN THE UPSLOPE REGION OF THE UINTA MOUNTAINS...THE AREA NORTHWEST
OF VERNAL NEEDS TO MONITORED FOR ANY FLOOD POTENTIAL GIVEN NEAR
SATURATED GROUND. AREAL FLOOD ADVISORY ALREADY ISSUED FOR ERN
DAGGETT COUNTY IN THE JARVIE RANCH AS GRAVEL/DIRT ROADS HAVE BEEN
REPORTEDLY WASHED OUT.
UPPER LOW WILL BE ABOVE THE WESTERN SLOPE WEDNESDAY AFTERNOON. MAY
NEED TO CONSIDER THIS A SPRING COLD CORE SYSTEM WITH HIGHER
PRECIPITABLE WATER CONTENT. THE RAIN COOLED AIR MASS WILL HAVE
STABILIZE THE AIR MASS...EXPECT AFTERNOON DESTABILIZATION FROM MID
LEVEL COLD ADVECTION. WITH LOWER FREEZING LEVELS...SOME THUNDERSTORMS
WILL CONTAIN HAIL. ISOLATED LARGE HAIL IS POSSIBLE (ALTHOUGH THE
WIND SHEAR PROFILE IS NOT FAVORABLE)...BUT THE MORE LIKELY
SCENARIO IS PLENTY OF SMALL HAIL WITH SIGNIFICANT ACCUMULATION.
THE COOL WET AUGUST FOR THE NORTHERN AND CENTRAL AREAS OF THE
FORECAST AREA CONTINUES FOR ANOTHER DAY.
UPDATE ISSUED AT 625 PM MDT TUE AUG 26 2014
ANOMALOUS CLOSED LOW WILL TRACK TOWARD WRN COLORADO TONIGHT AND
WILL BE OVERHEAD ON WEDNESDAY AFTERNOON. MOISTURE SURGING
NORTHEAST FROM SRN UTAH AND ARIZONA WILL EVENTUALLY WRAP AROUND
THE MID LEVEL CIRCULATION WITH PRECIPITATION MORE FOCUSED ACROSS
THE NORTH BY WEDNESDAY. APPEARS THAT MUCH OF THE AREA WILL RECEIVE
SHOWERS WITH EMBEDDED STORMS ON WEDNESDAY. WILL TAKE ANOTHER LOOK
AT THE FORECAST PACKAGE WHEN THE 00Z HRRR ARRIVES WITH POSSIBLE
FORECAST UPDATES FOR WEDNESDAY.
&&
.SHORT TERM...(TONIGHT THROUGH WEDNESDAY NIGHT)
ISSUED AT 234 PM MDT TUE AUG 26 2014
CONVECTION STARTING TO GET GOING THIS AFTERNOON THANKS TO THE
CLOSED LOW OVER UTAH...AVAILABLE MOISTURE...UPPER LEVEL TROUGH
ROTATING AROUND LOW AND UPPER LEVEL DYNAMIC SUPPORT. MODEL DIFFERENCES
CONTINUE WITH SOME MODELS BEING MORE AGGRESSIVE THAN OTHERS WITH
HRRR STILL DOING PRETTY WELL PICKING UP ON MOST CONVECTION ACROSS
NM...UT...AZ...AND CO. WHILE SOME SHOWERS AND STORMS ARE MOVING
ACROSS THE CWA...THE HRRR SHOWS THE STRONGER CONVECTION ENTERING
SERN UT THIS EVENING AND THIS LOOKS TO BE PANNING OUT AS A LINE OF
SHOWERS AND STORMS HAS FORMED OVER CENTRAL AND S CENTRAL UTAH AND
IS TRACKING EASTWARD. HIGH SPECIFIC HUMIDITIES LENDING THEMSELVES
TO SOME HEAVY RAINERS SO THE FLASH FLOOD WATCHES WILL REMAIN IN
EFFECT.
RAIN WITH SOME EMBEDDED STORMS WILL CONTINUE OVERNIGHT AS THE
UPPER LEVEL LOW APPROACHES THE FORECAST AREA. THE STORMS AND
SHOWERS OVER THE SAN JUANS WILL SHIFT NORTHWARD AS THE NIGHT
PROGRESSES AND BEST UPPER LEVEL SUPPORT ALSO SHIFTS TO THE
NORTH...STILL ROTATING AROUND THE LOW PRESSURE. SNOW LEVELS ARE
EXPECTED TO DROP NEAR 13K FEET OR SO OVERNIGHT WITH A LIGHT
DUSTING OF SNOW POSSIBLE FOR ELEVATIONS ABOVE THAT. FOR
TOMORROW...MOST PRECIP WILL BE UP NORTH AS THE LOW PRESSURE STARTS
TO FILL AND MOVE OVER UT AND CO. HOWEVER...AS THE LOW MOVES OVER
THE CWA DURING THE DAY UPPER LEVEL DYNAMICS WILL AGAIN PLAY A
FACTOR WITH MORE PRECIP ON TAP FOR MAINLY THE SAN JUANS NORTHWARD.
TEMPERATURES WILL STAY BELOW NORMAL THROUGH THE PERIOD DUE TO
PRECIP AND CLOUDINESS.
.LONG TERM...(THURSDAY THROUGH TUESDAY)
ISSUED AT 234 PM MDT TUE AUG 26 2014
THE UPPER TROUGH DROPS ONTO THE EASTERN PLAINS ON THURSDAY WITH
THE WESTERN MOST ASSOCIATED SHOWERS CLOSE TO THE CONTINENTAL
DIVIDE FAVORING NW-FACING SLOPES. THESE SHOWERS ARE EXPECTED TO
END BY THURSDAY EVENING.
A FLAT RIDGE TRIES TO BUILD IN FROM THE SOUTHWEST ON FRIDAY.
RESIDUAL MOISTURE WILL ALLOW LATE-DAY STORMS TO FIRE MAINLY OVER
THE HIGHER COLORADO TERRAIN. THE RIDGE GETS FLATTENED ON SATURDAY
AS THE NEXT GULF OF ALASKA TROUGH DIGS INTO THE PACIFIC NW.
SATURDAY STILL LOOKS LIKE THE WARMEST DAY OF THE WEEK PERHAPS
HITTING 90 DEGREES ONCE AGAIN IN GRAND JUNCTION AND NEAR 100 IN
THE SE UTAH LOWLANDS.
THE PACIFIC TROUGH WILL PROGRESS THROUGH THE NORTHERN ROCKIES
SUNDAY INTO MONDAY. ITS 100KT JET STREAK SWEEPS THROUGH SOUTHERN
WYOMING. THIS MAY PRODUCE SCATTERED STORMS ACROSS THE NORTHERN
MTNS SUNDAY WITH A FEW STORMS PERSISTING INTO MONDAY. THESE STORMS
WILL BE MOVING TO THE EAST AT 45 MPH SO STRONG WINDS ARE A THREAT.
ELSEWHERE SUNDAY AND MONDAY WILL HAVE BREEZY AFTERNOON WINDS WITH
A SLIGHT COOL DOWN RECOVERING SOMEWHAT ON TUESDAY AS THE TROUGH
WORKS ACROSS THE NORTHERN PLAINS.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z WEDNESDAY EVENING)
ISSUED AT 625 PM MDT TUE AUG 26 2014
NUMEROUS SHOWERS EXPECTED WITH EMBEDDED THUNDERSTORMS THROUGH THE
FORECAST PERIOD. THE STRONGEST STORMS WILL PRODUCE 4SM
+SHRA/+TSRAGS WITH CIGS LOWERING TO BELOW AIRFIELD MINIMUMS FOR
THE MOUNTAIN TAF SITES. CONVECTIVE TURBULENCE SHOULD BE EXPECTED
WITH OCCASIONAL MOUNTAIN TOP OBSCURATIONS. SOME IMPROVEMENT IS
EXPECTED ACROSS THE FAR SOUTH ON WEDNESDAY AFTERNOON WITH A
DECREASING CHANCE FOR -SHRA/-TSRA.
&&
.GJT WATCHES/WARNINGS/ADVISORIES...
CO...NONE.
UT...NONE.
&&
$$
UPDATE...PF
SHORT TERM...TGR
LONG TERM...JOE
AVIATION...PF
AREA FORECAST DISCUSSION
NWS GRAND JUNCTION CO
625 PM MDT TUE AUG 26 2014
.UPDATE...
ISSUED AT 625 PM MDT TUE AUG 26 2014
ANOMALOUS CLOSED LOW WILL TRACK TOWARD WRN COLORADO TONIGHT AND
WILL BE OVERHEAD ON WEDNESDAY AFTERNOON. MOISTURE SURGING
NORTHEAST FROM SRN UTAH AND ARIZONA WILL EVENTUALLY WRAP AROUND
THE MID LEVEL CIRCULATION WITH PRECIPITATION MORE FOCUSED ACROSS
THE NORTH BY WEDNESDAY. APPEARS THAT MUCH OF THE AREA WILL RECEIVE
SHOWERS WITH EMBEDDED STORMS ON WEDNESDAY. WILL TAKE ANOTHER LOOK
AT THE FORECAST PACKAGE WHEN THE 00Z HRRR ARRIVES WITH POSSIBLE
FORECAST UPDATES FOR WEDNESDAY.
&&
.SHORT TERM...(TONIGHT THROUGH WEDNESDAY NIGHT)
ISSUED AT 234 PM MDT TUE AUG 26 2014
CONVECTION STARTING TO GET GOING THIS AFTERNOON THANKS TO THE
CLOSED LOW OVER UTAH...AVAILABLE MOISTURE...UPPER LEVEL TROUGH
ROTATING AROUND LOW AND UPPER LEVEL DYNAMIC SUPPORT. MODEL DIFFERENCES
CONTINUE WITH SOME MODELS BEING MORE AGGRESSIVE THAN OTHERS WITH
HRRR STILL DOING PRETTY WELL PICKING UP ON MOST CONVECTION ACROSS
NM...UT...AZ...AND CO. WHILE SOME SHOWERS AND STORMS ARE MOVING
ACROSS THE CWA...THE HRRR SHOWS THE STRONGER CONVECTION ENTERING
SERN UT THIS EVENING AND THIS LOOKS TO BE PANNING OUT AS A LINE OF
SHOWERS AND STORMS HAS FORMED OVER CENTRAL AND S CENTRAL UTAH AND
IS TRACKING EASTWARD. HIGH SPECIFIC HUMIDITIES LENDING THEMSELVES
TO SOME HEAVY RAINERS SO THE FLASH FLOOD WATCHES WILL REMAIN IN
EFFECT.
RAIN WITH SOME EMBEDDED STORMS WILL CONTINUE OVERNIGHT AS THE
UPPER LEVEL LOW APPROACHES THE FORECAST AREA. THE STORMS AND
SHOWERS OVER THE SAN JUANS WILL SHIFT NORTHWARD AS THE NIGHT
PROGRESSES AND BEST UPPER LEVEL SUPPORT ALSO SHIFTS TO THE
NORTH...STILL ROTATING AROUND THE LOW PRESSURE. SNOW LEVELS ARE
EXPECTED TO DROP NEAR 13K FEET OR SO OVERNIGHT WITH A LIGHT
DUSTING OF SNOW POSSIBLE FOR ELEVATIONS ABOVE THAT. FOR
TOMORROW...MOST PRECIP WILL BE UP NORTH AS THE LOW PRESSURE STARTS
TO FILL AND MOVE OVER UT AND CO. HOWEVER...AS THE LOW MOVES OVER
THE CWA DURING THE DAY UPPER LEVEL DYNAMICS WILL AGAIN PLAY A
FACTOR WITH MORE PRECIP ON TAP FOR MAINLY THE SAN JUANS NORTHWARD.
TEMPERATURES WILL STAY BELOW NORMAL THROUGH THE PERIOD DUE TO
PRECIP AND CLOUDINESS.
.LONG TERM...(THURSDAY THROUGH TUESDAY)
ISSUED AT 234 PM MDT TUE AUG 26 2014
THE UPPER TROUGH DROPS ONTO THE EASTERN PLAINS ON THURSDAY WITH
THE WESTERN MOST ASSOCIATED SHOWERS CLOSE TO THE CONTINENTAL
DIVIDE FAVORING NW-FACING SLOPES. THESE SHOWERS ARE EXPECTED TO
END BY THURSDAY EVENING.
A FLAT RIDGE TRIES TO BUILD IN FROM THE SOUTHWEST ON FRIDAY.
RESIDUAL MOISTURE WILL ALLOW LATE-DAY STORMS TO FIRE MAINLY OVER
THE HIGHER COLORADO TERRAIN. THE RIDGE GETS FLATTENED ON SATURDAY
AS THE NEXT GULF OF ALASKA TROUGH DIGS INTO THE PACIFIC NW.
SATURDAY STILL LOOKS LIKE THE WARMEST DAY OF THE WEEK PERHAPS
HITTING 90 DEGREES ONCE AGAIN IN GRAND JUNCTION AND NEAR 100 IN
THE SE UTAH LOWLANDS.
THE PACIFIC TROUGH WILL PROGRESS THROUGH THE NORTHERN ROCKIES
SUNDAY INTO MONDAY. ITS 100KT JET STREAK SWEEPS THROUGH SOUTHERN
WYOMING. THIS MAY PRODUCE SCATTERED STORMS ACROSS THE NORTHERN
MTNS SUNDAY WITH A FEW STORMS PERSISTING INTO MONDAY. THESE STORMS
WILL BE MOVING TO THE EAST AT 45 MPH SO STRONG WINDS ARE A THREAT.
ELSEWHERE SUNDAY AND MONDAY WILL HAVE BREEZY AFTERNOON WINDS WITH
A SLIGHT COOL DOWN RECOVERING SOMEWHAT ON TUESDAY AS THE TROUGH
WORKS ACROSS THE NORTHERN PLAINS.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z WEDNESDAY EVENING)
ISSUED AT 625 PM MDT TUE AUG 26 2014
NUMEROUS SHOWERS EXPECTED WITH EMBEDDED THUNDERSTORMS THROUGH THE
FORECAST PERIOD. THE STRONGEST STORMS WILL PRODUCE 4SM
+SHRA/+TSRAGS WITH CIGS LOWERING TO BELOW AIRFIELD MINIMUMS FOR
THE MOUNTAIN TAF SITES. CONVECTIVE TURBULENCE SHOULD BE EXPECTED
WITH OCCASIONAL MOUNTAIN TOP OBSCURATIONS. SOME IMPROVEMENT IS
EXPECTED ACROSS THE FAR SOUTH ON WEDNESDAY AFTERNOON WITH A
DECREASING CHANCE FOR -SHRA/-TSRA.
&&
.GJT WATCHES/WARNINGS/ADVISORIES...
CO...FLASH FLOOD WATCH THROUGH WEDNESDAY MORNING FOR COZ018-019-
021>023.
UT...FLASH FLOOD WATCH UNTIL MIDNIGHT MDT TONIGHT FOR UTZ022-027-029.
&&
$$
UPDATE...PF
SHORT TERM...TGR
LONG TERM...JOE
AVIATION...PF
AREA FORECAST DISCUSSION
NWS PUEBLO CO
426 PM MDT MON AUG 25 2014
.UPDATE...
ISSUED AT 424 PM MDT MON AUG 25 2014
UPDATED FOR INCLUSION OF SVR TSTORM WATCH FOR EL PASO
CROWLEY AND KIOWA COUNTIES. ROSE
&&
.SHORT TERM...(THIS EVENING THROUGH TUESDAY)
ISSUED AT 305 PM MDT MON AUG 25 2014
CURRENTLY...COLD FRONT HAS BECOME STATIONARY NEAR THE NM BORDER
THIS AFTERNOON...AND WILL LIKELY DRIFT BACK NORTHWARD TOWARD THE
ARKANSAS RIVER BY 00Z. CONVECTION OVER THE MOUNTAINS AND ALONG THE
RATON MESA HAS BEEN RELATIVELY WEAK SO FAR AS STORMS HAVE YET TO
TAP DEEPER INSTABILITY NEAR THE KS BORDER AND FARTHER NORTH NEAR THE
PALMER DIVIDE. WITH COOL AIR SLIGHTLY DEEPER THAN EXPECTED...APPEARS
HIGH TEMPS WILL END UP JUST SHY OF FORECAST READINGS.
TONIGHT...MESOSCALE MODELS CONTINUE TO POINT TO AREAS ALONG AND
NORTH OF THE PALMER DIVIDE HAVING THE BEST CHANCE FOR STRONG/SEVERE
CONVECTION...THOUGH LATEST HRRR HINTS AT SOME SOME BRIEF STRONGER
STORMS OVER THE FAR EASTERN PLAINS...AS FRONTAL BOUNDARY RETREATING
NORTHWARD PROVIDES SOME ENHANCED CONVERGENCE. WEAK SHORT WAVE...OVER
WRN CO CURRENTLY...WILL ALSO PROVIDE SOME UPWARD MOTION AS IT
CROSSES THE AREA THIS EVENING. BY MIDNIGHT...SUSPECT CONVECTION WILL
SHIFT NORTHEAST AND COALESCE INTO AN MCS OVER NWRN KS/SRN NEB...WITH
FAIRLY LARGE COLD POOL GIVING SURFACE FRONT A RENEWED SHOVE
SOUTHWARD THROUGH THE EASTERN PLAINS. WITH A GRADUAL INCREASE IN MID
LEVEL MOISTURE THROUGH THE NIGHT AND BOUNDARY MOVING BACK
SOUTHWARD...WILL ONLY GRADUALLY TAPER OFF POPS THROUGH THE
EVENING...WITH AT LEAST SOME ISOLATED TSRA POSSIBLE PAST MIDNIGHT.
TUESDAY.. UPPER LOW WILL CONTINUE TO SLOWLY PUSH EASTWARD THROUGH
THE GREAT BASIN...WITH STRENGTHENING S-SW FLOW AHEAD OF THE SYSTEM
PUSHING AN INCREASING AMOUNT OF TROPICAL MOISTURE NORTHWARD INTO
COLORADO. SURFACE FRONT WILL LIKELY STAY SOUTH OF THE ARKANSAS RIVER
THROUGH THE DAY...WITH E-SE FLOW PUSHING 55F-60F DEWPOINTS WESTWARD
TOWARD THE I-25 CORRIDOR. WITH MOISTURE PLENTIFUL...EXPECT EARLY
INITIATION OF CONVECTION WITH STORMS FIRING OVER THE MOUNTAINS
BEFORE 18Z AND SPREADING QUICKLY TO LOWER ELEVATIONS BY 21Z. MAIN
THREAT TOMORROW OVER ALL AREAS WILL BE HEAVY RAINFALL...THOUGH WITH
CAPES OVER 1000 J/KG AND 0-6KM SHEAR OF 30-40 KTS...A SEVERE STORM
OR TWO IS POSSIBLE ON THE PLAINS MAINLY ALONG AND NORTH OF THE
ARKANSAS RIVER. ALL IN ALL...IT LOOKS LIKE A VERY WET DAY OVER MUCH
OF SOUTHERN COLORADO...AND WITH CLOUDS AND PRECIP FAIRLY QUICK TO
DEVELOP...MAX TEMPS SHOULD COOL AT LEAST A FEW DEGF VERSUS MON
READINGS.
.LONG TERM...(TUESDAY NIGHT THROUGH MONDAY)
ISSUED AT 305 PM MDT MON AUG 25 2014
TUESDAY NIGHT THROUGH FRIDAY...LATEST RUNS OF THE NAM...GFS AND EC
MODELS ARE IN FAIRLY GOOD AGREEMENT ON THE PROGRESSION OF THE UPPER
TROUGH ACROSS THE REGION THROUGH THIS WEEK. TUE EVENING THE TROUGH
WILL BE POISED OVER NV AND UT...CONTINUING TO DRAW A STRONG MOISTURE
PLUME UP ACROSS THE 4 CORNERS AND INTO CO. THE TROUGH STEADILY
MARCHES TO THE EAST ACROSS COLORADO THROUGH WED AND THU...WITH THE
TROUGH AXIS FINALLY REACHING THE OK AND TX PANHANDLES BY FRI
MORNING. A GOOD AMOUNT OF MOISTURE...COUPLED WITH AVAILABLE DYNAMICS
AND A COLD FRONT WED EVE WILL PROVIDE FOR WIDESPREAD CONVECTION
CHANCES THROUGH THE PERIOD...WITH PCPN FINALLY TAPERING OFF FRI
MORNING. LOOK FOR SCATTERED POPS FOR MUCH OF THE AREA TUE EVE AND
AGAIN WED EVE THROUGH THU...WITH PCPN LIKELY OVER THE MTS. TEMPS ARE
EXPECTED TO REMAIN COOLER THROUGH FRI WITH MAX TEMPS IN THE UPPER
70S AND 80S FOR THE PLAINS...AND 60S AND 70S FOR THE HIGH VALLEYS.
SATURDAY THROUGH MONDAY...AS THE TROUGH EXITS TO THE EAST...A RIDGE
OF HIGH PRESSURE BUILDS OVER THE SW US. THIS WILL HELP A DRYING AND
WARMING TREND TO TAKE HOLD OVER THE WEEKEND AND INTO THE FIRST PART
OF THE NEXT WORK WEEK. PCPN CHANCES ARE FORECAST TO BE RESTRICTED TO
JUST ISOLATED DIURNAL ACTIVITY OVER THE HIGHER TERRAIN...AND TEMPS
WILL CLIMB BACK UP INTO THE 80S NEARING 90 F FOR THE PLAINS...AND
INTO THE 80S FOR THE HIGH VALLEYS. MOORE
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON)
ISSUED AT 305 PM MDT MON AUG 25 2014
TSRA DEVELOPING OVER THE MOUNTAINS WILL CONTINUE TO SPREAD TO LOWER
ELEVATIONS THIS AFTERNOON...WITH STORMS NEAR KCOS AND KPUB IN THE
22Z-02Z PERIOD...AND AROUND KALS 22Z-01Z. WITH MORE MOISTURE
AVAILABLE TODAY...EXPECT LOWER CLOUD BASES AND RESTRICTED VISIBILITY
UNDER THE STRONGEST STORMS...AND LOCAL MVFR/BRIEF IFR CONDITIONS
WILL BE POSSIBLE. STORMS WILL GRADUALLY SHIFT INTO NORTHEAST
COLORADO THIS EVENING AND OVERNIGHT...WITH A COLD FRONT AND SHIFT TO
NORTHEAST WINDS PUSHING SOUTHWARD ACROSS THE PLAINS AFTER 00Z. MAY
SEE SOME IFR STRATUS ALONG THE PALMER DIVIDE BY 12Z TUE...BUT
HAVEN`T INCLUDED LOWER CLOUDS IN KCOS TAF AS NORTH WIND MAY KEEP
CLOUDS JUST NORTH OF THE AIRPORT. ON TUE...EXPECT WIDESPREAD TSRA
ALL AREAS...WITH EARLY STORM INITIATION OVER THE MOUNTAINS BY 18Z.
BY MID TO LATE AFTERNOON...MTS WILL BE OBSCURED AND MVFR CONDITIONS
WITH THUNDERSTORMS WILL BE POSSIBLE AT ALL TAF SITES.
&&
.PUB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...ROSE
SHORT TERM...PETERSEN
LONG TERM...MOORE
AVIATION...PETERSEN
AREA FORECAST DISCUSSION
NWS PUEBLO CO
305 PM MDT MON AUG 25 2014
.SHORT TERM...(THIS EVENING THROUGH TUESDAY)
ISSUED AT 305 PM MDT MON AUG 25 2014
CURRENTLY...COLD FRONT HAS BECOME STATIONARY NEAR THE NM BORDER
THIS AFTERNOON...AND WILL LIKELY DRIFT BACK NORTHWARD TOWARD THE
ARKANSAS RIVER BY 00Z. CONVECTION OVER THE MOUNTAINS AND ALONG THE
RATON MESA HAS BEEN RELATIVELY WEAK SO FAR AS STORMS HAVE YET TO
TAP DEEPER INSTABILITY NEAR THE KS BORDER AND FARTHER NORTH NEAR THE
PALMER DIVIDE. WITH COOL AIR SLIGHTLY DEEPER THAN EXPECTED...APPEARS
HIGH TEMPS WILL END UP JUST SHY OF FORECAST READINGS.
TONIGHT...MESOSCALE MODELS CONTINUE TO POINT TO AREAS ALONG AND
NORTH OF THE PALMER DIVIDE HAVING THE BEST CHANCE FOR STRONG/SEVERE
CONVECTION...THOUGH LATEST HRRR HINTS AT SOME SOME BRIEF STRONGER
STORMS OVER THE FAR EASTERN PLAINS...AS FRONTAL BOUNDARY RETREATING
NORTHWARD PROVIDES SOME ENHANCED CONVERGENCE. WEAK SHORT WAVE...OVER
WRN CO CURRENTLY...WILL ALSO PROVIDE SOME UPWARD MOTION AS IT
CROSSES THE AREA THIS EVENING. BY MIDNIGHT...SUSPECT CONVECTION WILL
SHIFT NORTHEAST AND COALESCE INTO AN MCS OVER NWRN KS/SRN NEB...WITH
FAIRLY LARGE COLD POOL GIVING SURFACE FRONT A RENEWED SHOVE
SOUTHWARD THROUGH THE EASTERN PLAINS. WITH A GRADUAL INCREASE IN MID
LEVEL MOISTURE THROUGH THE NIGHT AND BOUNDARY MOVING BACK
SOUTHWARD...WILL ONLY GRADUALLY TAPER OFF POPS THROUGH THE
EVENING...WITH AT LEAST SOME ISOLATED TSRA POSSIBLE PAST MIDNIGHT.
TUESDAY.. UPPER LOW WILL CONTINUE TO SLOWLY PUSH EASTWARD THROUGH
THE GREAT BASIN...WITH STRENGTHENING S-SW FLOW AHEAD OF THE SYSTEM
PUSHING AN INCREASING AMOUNT OF TROPICAL MOISTURE NORTHWARD INTO
COLORADO. SURFACE FRONT WILL LIKELY STAY SOUTH OF THE ARKANSAS RIVER
THROUGH THE DAY...WITH E-SE FLOW PUSHING 55F-60F DEWPOINTS WESTWARD
TOWARD THE I-25 CORRIDOR. WITH MOISTURE PLENTIFUL...EXPECT EARLY
INITIATION OF CONVECTION WITH STORMS FIRING OVER THE MOUNTAINS
BEFORE 18Z AND SPREADING QUICKLY TO LOWER ELEVATIONS BY 21Z. MAIN
THREAT TOMORROW OVER ALL AREAS WILL BE HEAVY RAINFALL...THOUGH WITH
CAPES OVER 1000 J/KG AND 0-6KM SHEAR OF 30-40 KTS...A SEVERE STORM
OR TWO IS POSSIBLE ON THE PLAINS MAINLY ALONG AND NORTH OF THE
ARKANSAS RIVER. ALL IN ALL...IT LOOKS LIKE A VERY WET DAY OVER MUCH
OF SOUTHERN COLORADO...AND WITH CLOUDS AND PRECIP FAIRLY QUICK TO
DEVELOP...MAX TEMPS SHOULD COOL AT LEAST A FEW DEGF VERSUS MON
READINGS.
.LONG TERM...(TUESDAY NIGHT THROUGH MONDAY)
ISSUED AT 305 PM MDT MON AUG 25 2014
TUESDAY NIGHT THROUGH FRIDAY...LATEST RUNS OF THE NAM...GFS AND EC
MODELS ARE IN FAIRLY GOOD AGREEMENT ON THE PROGRESSION OF THE UPPER
TROUGH ACROSS THE REGION THROUGH THIS WEEK. TUE EVENING THE TROUGH
WILL BE POISED OVER NV AND UT...CONTINUING TO DRAW A STRONG MOISTURE
PLUME UP ACROSS THE 4 CORNERS AND INTO CO. THE TROUGH STEADILY
MARCHES TO THE EAST ACROSS COLORADO THROUGH WED AND THU...WITH THE
TROUGH AXIS FINALLY REACHING THE OK AND TX PANHANDLES BY FRI
MORNING. A GOOD AMOUNT OF MOISTURE...COUPLED WITH AVAILABLE DYNAMICS
AND A COLD FRONT WED EVE WILL PROVIDE FOR WIDESPREAD CONVECTION
CHANCES THROUGH THE PERIOD...WITH PCPN FINALLY TAPERING OFF FRI
MORNING. LOOK FOR SCATTERED POPS FOR MUCH OF THE AREA TUE EVE AND
AGAIN WED EVE THROUGH THU...WITH PCPN LIKELY OVER THE MTS. TEMPS ARE
EXPECTED TO REMAIN COOLER THROUGH FRI WITH MAX TEMPS IN THE UPPER
70S AND 80S FOR THE PLAINS...AND 60S AND 70S FOR THE HIGH VALLEYS.
SATURDAY THROUGH MONDAY...AS THE TROUGH EXITS TO THE EAST...A RIDGE
OF HIGH PRESSURE BUILDS OVER THE SW US. THIS WILL HELP A DRYING AND
WARMING TREND TO TAKE HOLD OVER THE WEEKEND AND INTO THE FIRST PART
OF THE NEXT WORK WEEK. PCPN CHANCES ARE FORECAST TO BE RESTRICTED TO
JUST ISOLATED DIURNAL ACTIVITY OVER THE HIGHER TERRAIN...AND TEMPS
WILL CLIMB BACK UP INTO THE 80S NEARING 90 F FOR THE PLAINS...AND
INTO THE 80S FOR THE HIGH VALLEYS. MOORE
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON)
ISSUED AT 305 PM MDT MON AUG 25 2014
TSRA DEVELOPING OVER THE MOUNTAINS WILL CONTINUE TO SPREAD TO LOWER
ELEVATIONS THIS AFTERNOON...WITH STORMS NEAR KCOS AND KPUB IN THE
22Z-02Z PERIOD...AND AROUND KALS 22Z-01Z. WITH MORE MOISTURE
AVAILABLE TODAY...EXPECT LOWER CLOUD BASES AND RESTRICTED VISIBILITY
UNDER THE STRONGEST STORMS...AND LOCAL MVFR/BRIEF IFR CONDITIONS
WILL BE POSSIBLE. STORMS WILL GRADUALLY SHIFT INTO NORTHEAST
COLORADO THIS EVENING AND OVERNIGHT...WITH A COLD FRONT AND SHIFT TO
NORTHEAST WINDS PUSHING SOUTHWARD ACROSS THE PLAINS AFTER 00Z. MAY
SEE SOME IFR STRATUS ALONG THE PALMER DIVIDE BY 12Z TUE...BUT
HAVEN`T INCLUDED LOWER CLOUDS IN KCOS TAF AS NORTH WIND MAY KEEP
CLOUDS JUST NORTH OF THE AIRPORT. ON TUE...EXPECT WIDESPREAD TSRA
ALL AREAS...WITH EARLY STORM INITIATION OVER THE MOUNTAINS BY 18Z.
BY MID TO LATE AFTERNOON...MTS WILL BE OBSCURED AND MVFR CONDITIONS
WITH THUNDERSTORMS WILL BE POSSIBLE AT ALL TAF SITES.
&&
.PUB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...PETERSEN
LONG TERM...MOORE
AVIATION...PETERSEN
AREA FORECAST DISCUSSION
NWS GRAND JUNCTION CO
151 AM MDT MON AUG 25 2014
.UPDATE...
ISSUED AT 146 AM MDT MON AUG 25 2014
QUICK UPDATE TO BOOST POPS ACROSS THE CENTRAL ZONES AS ACTIVITY
DEVELOPS ALONG OUTFLOW BOUNDARIES AND EDGE OF DEEPER SHEER TO THE
NORTH. NO OTHER CHANGES ATTM WITH NEW GRIDS OUT SHORTLY.
UPDATE ISSUED AT 1036 PM MDT SUN AUG 24 2014
CONVECTION CONTINUES TO EXPAND IN AREAL COVERAGE ALONG AND NORTH
OF UPPER LEVEL JET LIFTING NORTHEAST ACROSS THE FORECAST AREA
LATE THIS EVENING. FEW STRONGER CELLS DEVELOPING WITH NUMEROUS
OUTFLOW BOUNDARIES KICKING UP STRONGER SFC WINDS. LATEST HRRR RUNS
INDICATE THIS WILL CONTINUE THROUGH THE REMAINDER OF THE NIGHT AND
HAVE MADE SIGNIFICANT ADJUSTMENTS TO POPS GRIDS TO FIT CURRENT
TRENDS AND EXPECTED CONDITIONS FOR THE REMAINDER OF THE NIGHT.
OUTFLOW GUSTS TO 40 MPH POSSIBLE TONIGHT ALONG WITH SMALL HAIL
NEAR THE STRONGER CELLS. OTHERWISE...MORE MUCH NEEDED RAIN FOR THE
NORTHERN PORTIONS OF OUR FORECAST AREA.
UPDATE ISSUED AT 550 PM MDT SUN AUG 24 2014
SHORT TERM UPDATE WILL BE REQUIRED EARLY THIS EVENING AS
CONVECTION HAS INCREASED ACROSS EAST CENTRAL UTAH. THIS ACTIVITY
MAY EXPAND INTO NW COLORADO...POSSIBLY AS FAR AS A LINE FROM MOAB
TO ASPEN. THIS ACTIVITY IS IN RESPONSE TO EMBEDDED DISTURBANCE
ALONG A SHEAR AXIS THAT CUTS ACROSS THE FORECAST AREA THIS
EVENING. RAP AND HRRR MODELS INDICATE THAT SHOWERS AND STORMS
LASTING WELL BEYOND SUNSET WILL OCCUR FROM VERNAL TO ROUTT COUNTY.
IT APPEARS THAT THE LOWER RESOLUTION SUCH AS THE GFS40 IS
SUGGESTING NOCTURNAL CONVECTION AS WELL. UPDATE WILL BE COMING AND
WILL BE LEANING TOWARDS THE RAP/HRRR MODELS.
&&
.SHORT TERM...(TONIGHT THROUGH MONDAY NIGHT)
ISSUED AT 255 PM MDT SUN AUG 24 2014
12Z H5 HAND ANALYSIS SHOWING A BLOCKING RIDGE EXTENDING FROM THE
GULF STATES UP INTO THE CANADIAN MARITIME REGION. AS SUCH LOW
PRESSURE WILL BE ANCHORING IN THE WESTERN STATES TO START OUT THE
NEW WEEK. THE MORE IMPRESSIVE FEATURES SHOWING UP IN WATER VAPOR
THIS AFTERNOON ARE THE PAIR OF LOWS ROTATING AROUND EACH OTHER OVER
MONTANA AND WASHINGTON THIS AFTERNOON. THE FORMER RETREATING
NORTHEASTWARD AND THE LATTER DROPPING SOUTHWARD WHERE IT WILL CARVE
OUT A FAIRLY AMPLIFIED TROUGH THROUGH THE GREAT BASIN BY EARLY
TUESDAY. DERIVED IMAGERY AND RAOB DATA SHOWS A SIGNIFICANT DECREASE
IN MOISTURE THE PAST 24 HOURS AS THE MONSOONAL PLUME HAS BEEN
DIRECTED INTO THE EASTERN PLAINS. AT GJT AND UPSTREAM PWATS ARE
BELOW NORMAL FOR THIS TIME OF YEAR. THERE ARE SOME RETURNS SHOWING
UP ON RADAR WITH LOW LEVEL MOISTURE...MOUNTAIN CIRCULATIONS AND
INSTABILITY BEING ENHANCED BY A JET ALOFT. THE FOCUS FOR OVERNIGHT
SHOULD MAINLY BE ACROSS THE NORTH WHERE VEERING MID LEVEL PROFILES
AND THE PASSING JET MAXIMA WILL ADD JUST ENOUGH ASCENT TO KEEP
NOCTURNAL CONVECTION FIRING. HAVE THROWN OUT THE AGGRESSIVE GFS
QPF OUTPUT ATTM WITH IT NOT VERIFYING SO FAR THIS AFTERNOON. THETA
SURFACES NEAR 315K SHOW DECENT UPGLIDE NORTH OF INTERSTATE 70
TONIGHT WHILE ALSO HINT AT SOME TAP TO THE TROPICAL MOISTURE LEFT
OVER FROM WHAT IS LEFT OF MARIE. THIS TAP DOES NOT LOOK TO GREATLY
ENHANCE THE MOISTURE ADVECTION TONIGHT BUT MAY PLAY SOME ROLE IN
STORM FORMATION OVER THE EASTERN DIVIDE MOUNTAINS FOR MONDAY.
AGAIN MONDAY LOOKS TO BE SOMEWHAT OF A DOWN DAY AS THE JET ALOFT
WEAKENS AND OVERALL PWATS REMAIN BELOW NORMAL. A SMALL RIBBON OF
THE MOISTURE MENTIONED ABOVE LOOKS TO FAVOR CONVECTION OVER THE
CENTRAL DIVIDE MOUNTAINS UNDER CONFLUENT FLOW ALOFT. THIS ALL
HANDLED WELL IN THE GOING GRID FORECAST SO ONLY SMALL TWEAKS
NEEDED. TEMPERATURES SHOULD BE A BIT MORE MILD OVERNIGHT UNDER WAA
AND PUSH SOME 3 TO 7 DEGREES UPWARD FOR TUESDAY. TUESDAY NIGHT THE
FLOW BACKS MORE SOUTHERLY ALOFT AS THE MAIN TROF AXIS BECOME
ORIENTED MORE MERIDIONALLY. MONSOON AND TROPICAL MOISTURE LOOK TO
BE FORCED NORTHWARD IN THIS FLOW AND THERE SHOULD BE AN INCREASE
IN CONVECTION FROM MIDNIGHT TOWARD SUNRISE...SETTING UP A MORE
ACTIVE DAY FOR TUESDAY.
.LONG TERM...(TUESDAY THROUGH SUNDAY)
ISSUED AT 255 PM MDT SUN AUG 24 2014
THE CHALLENGE OF THESE PERIODS HAS BEEN THE TIMING AND THEREFORE
THE PLACEMENT OF THE UPPER LOW THAT WILL DIG OVER THE REGION. THE
EC AND NAM ARE IN GOOD AGREEMENT WITH A SLOWER SOLUTION. THE GFS
AND CANADIAN PRODUCE A FASTER PROGRESSION BUT THE GFS IS SLOWER
THAN ITS PREVIOUS RUNS. AS THE UPPER LOW IS DECOUPLED FROM THE
POLAR FRONT JET...THE SLOWEST EC SOLUTION IS PREFERRED. SO
INCREASED STORM COVERAGE AND COOLER TEMPS ARE EXPECTED THROUGH
THURSDAY.
TUESDAY...THE UPPER LOW DUG INTO EASTERN NEVADA ENHANCING A 75KT
JET OVER THIS CWA. MOISTURE SURGES TO OVER AN INCH PRECIPITABLE
WATER VALUES IN SE UTAH. WEDNESDAY THE UPPER LOW SLOWLY PROGRESSES
INTO NE UTAH LOSING JET SUPPORT BUT GAINING CYCLONIC AND DIVERGENT
FLOW ALOFT. PRECIP WATER VALUES REMAIN NEAR ONE INCH. STORM MOTION
ALSO REMAINS BRISKLY TO THE NE AT 20 KTS LIMITING RAINFALL FORM
ANY SINGLE STORM. BY THURSDAY THE LOW CENTER AMBLES TO THE
CONTINENTAL DIVIDE WITH WRAP-AROUND DYNAMICS ACROSS THE NORTHERN
CWA AND THE UPPER FLOW SWITCHING TO NW. SOME NOCTURNAL STORMS ARE
EXPECTED THROUGH THESE PERIODS.
BY FRIDAY THE EC PROGRESSES THE OPENING LOW ONTO THE EASTERN
PLAINS WITH A RIDGE BUILDING IN FROM THE WEST. FRIDAY STORM
ACTIVITY WILL LINGER ALONG THE CONTINENTAL DIVIDE...THEN A DRYING
AND WARMING TREND INTO THE WEEKEND.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT)
ISSUED AT 1036 PM MDT SUN AUG 24 2014
SHOWERS AND THUNDERSTORMS WILL CONTINUE ACROSS NORTHEAST UTAH AND
NORTHWEST COLORADO THROUGH 15Z MONDAY MORNING. GUSTY WINDS TO 40
MPH AND SMALL HAIL WILL OCCUR NEAR THE STRONGEST STORMS. LOCAL
MVFR CIGS POSSIBLE WITH MOUNTAINS BECOMING OBSCURED AT TIMES.
SOUTH OF INTERSTATE 70...VFR CONDITIONS EXPECTED TO PERSIST
THROUGH MIDDAY MONDAY.
AFTER 18Z...SCATTERED SHOWERS AND THUNDERSTORMS WILL REDEVELOP
OVER THE MOUNTAINS WITH ACTIVITY TRANSITIONING OUT OVER THE
VALLEYS AFTER 00Z MONDAY EVENING. WITH ANY STORMS...GUSTY
WINDS...HAIL AND LOWERED CIGS SHOULD BE EXPECTED...WITH MOUNTAIN
TOPS BECOMING OBSCURED.
&&
.GJT WATCHES/WARNINGS/ADVISORIES...
CO...NONE.
UT...NONE.
&&
$$
UPDATE...JDC
SHORT TERM...15
LONG TERM...JOE
AVIATION...JDC
AREA FORECAST DISCUSSION
NWS GRAND JUNCTION CO
1043 PM MDT SUN AUG 24 2014
.UPDATE...
ISSUED AT 1036 PM MDT SUN AUG 24 2014
CONVECTION CONTINUES TO EXPAND IN AREAL COVERAGE ALONG AND NORTH
OF UPPER LEVEL JET LIFTING NORTHEAST ACROSS THE FORECAST AREA
LATE THIS EVENING. FEW STRONGER CELLS DEVELOPING WITH NUMEROUS
OUTFLOW BOUNDARIES KICKING UP STRONGER SFC WINDS. LATEST HRRR RUNS
INDICATE THIS WILL CONTINUE THROUGH THE REMAINDER OF THE NIGHT AND
HAVE MADE SIGNIFICANT ADJUSTMENTS TO POPS GRIDS TO FIT CURRENT
TRENDS AND EXPECTED CONDITIONS FOR THE REMAINDER OF THE NIGHT.
OUTFLOW GUSTS TO 40 MPH POSSIBLE TONIGHT ALONG WITH SMALL HAIL
NEAR THE STRONGER CELLS. OTHERWISE...MORE MUCH NEEDED RAIN FOR THE
NORTHERN PORTIONS OF OUR FORECAST AREA.
UPDATE ISSUED AT 550 PM MDT SUN AUG 24 2014
SHORT TERM UPDATE WILL BE REQUIRED EARLY THIS EVENING AS
CONVECTION HAS INCREASED ACROSS EAST CENTRAL UTAH. THIS ACTIVITY
MAY EXPAND INTO NW COLORADO...POSSIBLY AS FAR AS A LINE FROM MOAB
TO ASPEN. THIS ACTIVITY IS IN RESPONSE TO EMBEDDED DISTURBANCE
ALONG A SHEAR AXIS THAT CUTS ACROSS THE FORECAST AREA THIS
EVENING. RAP AND HRRR MODELS INDICATE THAT SHOWERS AND STORMS
LASTING WELL BEYOND SUNSET WILL OCCUR FROM VERNAL TO ROUTT COUNTY.
IT APPEARS THAT THE LOWER RESOLUTION SUCH AS THE GFS40 IS
SUGGESTING NOCTURNAL CONVECTION AS WELL. UPDATE WILL BE COMING AND
WILL BE LEANING TOWARDS THE RAP/HRRR MODELS.
&&
.SHORT TERM...(TONIGHT THROUGH MONDAY NIGHT)
ISSUED AT 255 PM MDT SUN AUG 24 2014
12Z H5 HAND ANALYSIS SHOWING A BLOCKING RIDGE EXTENDING FROM THE
GULF STATES UP INTO THE CANADIAN MARITIME REGION. AS SUCH LOW
PRESSURE WILL BE ANCHORING IN THE WESTERN STATES TO START OUT THE
NEW WEEK. THE MORE IMPRESSIVE FEATURES SHOWING UP IN WATER VAPOR
THIS AFTERNOON ARE THE PAIR OF LOWS ROTATING AROUND EACH OTHER OVER
MONTANA AND WASHINGTON THIS AFTERNOON. THE FORMER RETREATING
NORTHEASTWARD AND THE LATTER DROPPING SOUTHWARD WHERE IT WILL CARVE
OUT A FAIRLY AMPLIFIED TROUGH THROUGH THE GREAT BASIN BY EARLY
TUESDAY. DERIVED IMAGERY AND RAOB DATA SHOWS A SIGNIFICANT DECREASE
IN MOISTURE THE PAST 24 HOURS AS THE MONSOONAL PLUME HAS BEEN
DIRECTED INTO THE EASTERN PLAINS. AT GJT AND UPSTREAM PWATS ARE
BELOW NORMAL FOR THIS TIME OF YEAR. THERE ARE SOME RETURNS SHOWING
UP ON RADAR WITH LOW LEVEL MOISTURE...MOUNTAIN CIRCULATIONS AND
INSTABILITY BEING ENHANCED BY A JET ALOFT. THE FOCUS FOR OVERNIGHT
SHOULD MAINLY BE ACROSS THE NORTH WHERE VEERING MID LEVEL PROFILES
AND THE PASSING JET MAXIMA WILL ADD JUST ENOUGH ASCENT TO KEEP
NOCTURNAL CONVECTION FIRING. HAVE THROWN OUT THE AGGRESSIVE GFS
QPF OUTPUT ATTM WITH IT NOT VERIFYING SO FAR THIS AFTERNOON. THETA
SURFACES NEAR 315K SHOW DECENT UPGLIDE NORTH OF INTERSTATE 70
TONIGHT WHILE ALSO HINT AT SOME TAP TO THE TROPICAL MOISTURE LEFT
OVER FROM WHAT IS LEFT OF MARIE. THIS TAP DOES NOT LOOK TO GREATLY
ENHANCE THE MOISTURE ADVECTION TONIGHT BUT MAY PLAY SOME ROLE IN
STORM FORMATION OVER THE EASTERN DIVIDE MOUNTAINS FOR MONDAY.
AGAIN MONDAY LOOKS TO BE SOMEWHAT OF A DOWN DAY AS THE JET ALOFT
WEAKENS AND OVERALL PWATS REMAIN BELOW NORMAL. A SMALL RIBBON OF
THE MOISTURE MENTIONED ABOVE LOOKS TO FAVOR CONVECTION OVER THE
CENTRAL DIVIDE MOUNTAINS UNDER CONFLUENT FLOW ALOFT. THIS ALL
HANDLED WELL IN THE GOING GRID FORECAST SO ONLY SMALL TWEAKS
NEEDED. TEMPERATURES SHOULD BE A BIT MORE MILD OVERNIGHT UNDER WAA
AND PUSH SOME 3 TO 7 DEGREES UPWARD FOR TUESDAY. TUESDAY NIGHT THE
FLOW BACKS MORE SOUTHERLY ALOFT AS THE MAIN TROF AXIS BECOME
ORIENTED MORE MERIDIONALLY. MONSOON AND TROPICAL MOISTURE LOOK TO
BE FORCED NORTHWARD IN THIS FLOW AND THERE SHOULD BE AN INCREASE
IN CONVECTION FROM MIDNIGHT TOWARD SUNRISE...SETTING UP A MORE
ACTIVE DAY FOR TUESDAY.
.LONG TERM...(TUESDAY THROUGH SUNDAY)
ISSUED AT 255 PM MDT SUN AUG 24 2014
THE CHALLENGE OF THESE PERIODS HAS BEEN THE TIMING AND THEREFORE
THE PLACEMENT OF THE UPPER LOW THAT WILL DIG OVER THE REGION. THE
EC AND NAM ARE IN GOOD AGREEMENT WITH A SLOWER SOLUTION. THE GFS
AND CANADIAN PRODUCE A FASTER PROGRESSION BUT THE GFS IS SLOWER
THAN ITS PREVIOUS RUNS. AS THE UPPER LOW IS DECOUPLED FROM THE
POLAR FRONT JET...THE SLOWEST EC SOLUTION IS PREFERRED. SO
INCREASED STORM COVERAGE AND COOLER TEMPS ARE EXPECTED THROUGH
THURSDAY.
TUESDAY...THE UPPER LOW DUG INTO EASTERN NEVADA ENHANCING A 75KT
JET OVER THIS CWA. MOISTURE SURGES TO OVER AN INCH PRECIPITABLE
WATER VALUES IN SE UTAH. WEDNESDAY THE UPPER LOW SLOWLY PROGRESSES
INTO NE UTAH LOSING JET SUPPORT BUT GAINING CYCLONIC AND DIVERGENT
FLOW ALOFT. PRECIP WATER VALUES REMAIN NEAR ONE INCH. STORM MOTION
ALSO REMAINS BRISKLY TO THE NE AT 20 KTS LIMITING RAINFALL FORM
ANY SINGLE STORM. BY THURSDAY THE LOW CENTER AMBLES TO THE
CONTINENTAL DIVIDE WITH WRAP-AROUND DYNAMICS ACROSS THE NORTHERN
CWA AND THE UPPER FLOW SWITCHING TO NW. SOME NOCTURNAL STORMS ARE
EXPECTED THROUGH THESE PERIODS.
BY FRIDAY THE EC PROGRESSES THE OPENING LOW ONTO THE EASTERN
PLAINS WITH A RIDGE BUILDING IN FROM THE WEST. FRIDAY STORM
ACTIVITY WILL LINGER ALONG THE CONTINENTAL DIVIDE...THEN A DRYING
AND WARMING TREND INTO THE WEEKEND.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT)
ISSUED AT 1036 PM MDT SUN AUG 24 2014
SHOWERS AND THUNDERSTORMS WILL CONTINUE ACROSS NORTHEAST UTAH AND
NORTHWEST COLORADO THROUGH 15Z MONDAY MORNING. GUSTY WINDS TO 40
MPH AND SMALL HAIL WILL OCCUR NEAR THE STRONGEST STORMS. LOCAL
MVFR CIGS POSSIBLE WITH MOUNTAINS BECOMING OBSCURED AT TIMES.
SOUTH OF INTERSTATE 70...VFR CONDITIONS EXPECTED TO PERSIST
THROUGH MIDDAY MONDAY.
AFTER 18Z...SCATTERED SHOWERS AND THUNDERSTORMS WILL REDEVELOP
OVER THE MOUNTAINS WITH ACTIVITY TRANSITIONING OUT OVER THE
VALLEYS AFTER 00Z MONDAY EVENING. WITH ANY STORMS...GUSTY
WINDS...HAIL AND LOWERED CIGS SHOULD BE EXPECTED...WITH MOUNTAIN
TOPS BECOMING OBSCURED.
&&
.GJT WATCHES/WARNINGS/ADVISORIES...
CO...NONE.
UT...NONE.
&&
$$
UPDATE...JDC
SHORT TERM...15
LONG TERM...JOE
AVIATION...JDC
AREA FORECAST DISCUSSION
NWS MIAMI FL
312 PM EDT MON AUG 25 2014
.DISCUSSION...A BACKDOOR TROUGH IS MOVING SOUTHWEST ACROSS THE
LOCAL AREA THIS AFTERNOON, BRINGING A SURGE IN MOISTURE ALONG
WITH IT. THIS HAS CAUSED SCATTERED FAST MOVING SHOWERS AND JUST A
FEW TSTORMS TO AFFECT SOUTH FL. ACTIVITY COULD BECOME SLIGHTLY
MORE FOCUSED ALONG THE GULF COAST OVER THE NEXT FEW HR. MAIN
IMPACTS WILL BE BRIEF HEAVY DOWNPOURS, GUSTY WINDS AND LIGHTNING
STRIKES...THOUGH THERE HAVE NOT BEEN MANY SO FAR TODAY.
THE TROUGH WILL MOVE SOUTH OF THE AREA TONIGHT AS CRISTOBAL
DISTANCES ITSELF FROM THE BAHAMAS. NE WINDS WILL INCREASE BEHIND
IT ALONG WITH SIGNIFICANT DRYING ALOFT. IN FACT...GOES SOUNDER
DATA SHOWS PWAT NOW AT AROUND 2 INCHES OVER SOUTH FL...BUT ONLY
ABOUT 1.25 INCHES MOVING INTO NORTHEAST FL AND INTO THE ATLANTIC
OFF EAST CENTRAL FL. THIS LOWER PWAT AIR WILL MOVE SOUTHWARD AND
OVER THE AREA TOMORROW (PUTTING US IN THE LOWER 25TH PERCENTILE
FOR THIS TIME OF THE YEAR)...LEADING TO LESS CONVECTIVE ACTIVITY
THAN NORMAL FOR SUMMERTIME. HAVE ONLY GONE WITH SLIGHT CHANCE POPS
TOMORROW WITH NO TSTORMS EXPECTED. HARD TO GET MUCH "FEEL" CHANGE
TO THE AIRMASS THOUGH GIVEN WINDS BLOWING OVER OUR UPPER 80 TO
NEAR 90 DEGREE WATERS. STILL...DEWPOINTS ARE FORECAST TO FALL INTO
THE LOWER 70S ATLANTIC COAST AND NEAR 70F INTERIOR- GULF COAST
WHICH IS BETTER THAN THE UPPER 70-DEGREE DEWPOINTS CURRENTLY IN
PLACE THOUGH! THIS "REPRIEVE" WON`T LAST LONG WITH MOISTURE
RECOVERY BEGINNING WEDNESDAY WITH A RETURN TO A MORE TYPICAL
SUMMERTIME REGIME -- HOT,HUMID WITH SCATTERED AFTERNOON
THUNDERSTORMS EACH DAY THROUGH WEEK`S END. /GREGORIA
&&
.MARINE...A SMALL CRAFT ADVISORY WILL BE IN EFFECT FOR THE PALM
BEACH AND OFF SHORE GULF WATERS BEGINNING AT 8 PM THIS EVENING AND
CONTINUING THROUGH THE NIGHT FOR NE WINDS SUSTAINED NEAR 20 KT.
SEAS IN THE GULF STREAM WILL BUILD TO NEAR 7 FEET OVERNIGHT IN
RESPONSE. THE SCA MAY NEED TO BE EXTENDED IN TIME FOR THE PALM
BEACH WATERS DUE TO HAZARDOUS GULF STREAM SEAS. WINDS/SEAS WILL
THEN SUBSIDE MID-LATE WEEK. /GREGORIA
&&
.AVIATION...SCATTERED SHOWERS AND A FEW ISOLATED THUNDERSTORMS CONTINUE
TO PUSH SOUTH ACROSS THE AREA THIS AFTERNOON. LATEST HRRR DEPICTS
ADDITIONAL SHOWERS THROUGH THE REST OF THE DAY WITHOUT ROBUST
CONVECTIVE DEVELOPMENT. THEREFORE REMOVED VCTS MENTION FROM ALL
SITES EXCEPT FOR KAPF. HOWEVER...CANNOT RULE OUT AN ISOLATED TSRA
TO BRIEFLY AFFECT A TAF SITE THROUGH THE EVENING. WINDS HAVE BEGUN
TO TURN MORE NORTHEASTERLY FROM KOPF SOUTHWARD AND SHOULD PREVAIL
AROUND 10 KNOTS THROUGH THE NIGHT. /CD
&&
.PRELIMINARY POINT TEMPS/POPS...
WEST PALM BEACH 79 90 78 90 / 20 20 20 30
FORT LAUDERDALE 81 91 80 91 / 20 20 20 30
MIAMI 80 91 79 91 / 20 20 20 40
NAPLES 78 92 77 91 / 20 20 10 40
&&
.MFL WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
AM...SMALL CRAFT ADVISORY FROM 8 PM THIS EVENING TO 8 AM EDT TUESDAY
FOR AMZ650-670.
GM...SMALL CRAFT ADVISORY FOR WINDS FROM 8 PM THIS EVENING TO 8 AM
EDT TUESDAY FOR GMZ676.
&&
$$
AREA FORECAST DISCUSSION
NWS MIAMI FL
1030 AM EDT MON AUG 25 2014
.UPDATE...A SURFACE TROUGH IS LOCATED ALONG THE PALM BEACH-MARTIN
COUNTY LINE AT THIS TIME...AND WILL MOVE SOUTHWEST ACROSS SOUTH
FLORIDA TODAY. MOISTURE AND CONVERGENCE ALONG THIS FEATURE...ALONG
WITH ADDITIONAL CONVERGENCE AIDED BY THE SEA BREEZES...WILL LEAD
TO A GOOD COVERAGE OF THUNDERSTORMS THIS AFTERNOON. A FEW COULD
CONTAIN GUSTY WINDS TO AROUND 50 MPH GIVEN THE PRESENCE OF DRY
MID LEVEL AIR AND INSTABILITY. THE INHERITED FORECAST LOOKS GOOD
WITH CURRENT AND EXPECTED TRENDS, SO NO SIGNIFICANT CHANGES ARE
NECESSARY THIS MORNING. WINDS WILL PICK UP BEHIND THIS TROUGH WITH
A SMALL CRAFT ADVISORY POSSIBLY NEEDED BY THIS EVENING FOR THE
PALM BEACH WATERS. FOLLOW US ON TWITTER @NWSMIAMI. /GREGORIA
&&
.PREV DISCUSSION... /ISSUED 749 AM EDT MON AUG 25 2014/
AVIATION...
SURFACE FLOW SHOULD REMAIN NORTHERLY THROUGH THE MORNING TO
NORTHEAST BY THE AFTERNOON. A SURGE OF ASSOCIATED MOISTURE WILL
KEEP ISOLATED TO SCATTERED SHOWERS PUSHING SOUTH ACROSS THE
ATLANTIC WATERS THROUGH THE MORNING. A FEW OF THESE SHOWERS MAY
MAKE IT INTO KFXE SOUTHWARD. THEREFORE KEPT VCSH AT THESE
TERMINALS THROUGH THE REMAINDER OF THE MORNING. OTHERWISE...VFR
CONDITIONS ARE EXPECTED OUTSIDE OF ANY AFTERNOON CONVECTION.
PREV DISCUSSION... /ISSUED 256 AM EDT MON AUG 25 2014/
SHORT TERM (TODAY-WEDNESDAY)...
IT CONTINUES TO LOOK MORE FAVORABLE THAT T.S. CRISTOBAL WILL MOVE
NORTH AND NORTHEAST AWAY FROM SOUTH FLORIDA. SO THE PRIMARY IMPACTS
WILL BE AN INCREASE IN RIP CURRENTS AT THE ATLANTIC BEACHES AND
BUILDING SEAS IN THE ATLANTIC FOR MARINE INTERESTS AS A SMALL
NORTHEAST SWELL IS GENERATED. MODELS SUGGEST A MOISTURE SURGE MOVING
INTO THE REGION AFTER 12Z THIS MORNING WHICH IS A RESULT IN THE
NORTHEAST CIRCULATION DEVELOPING WITH CRISTOBAL. THE CURRENT PWAT IS
AROUND 1.75 INCHES WITH FORECAST SOUNDINGS SHOWING AN INCREASE TO 2+
INCHES THIS MORNING. THE STEERING FLOW WILL BE NORTHEAST TO
SOUTHWEST SO THE EAST COAST COULD GET A QUICK PASSING SHRA/TSRA WITH
THE GREATEST ACTIVITY BEING OVER THE INTERIOR AND SOUTHWEST COAST.
THE HRRR IS SHOWING SOMETHING VERY SIMILAR WITH SCATTERED SHOWERS
NEAR THE EAST COAST WITH A FLARE UP INLAND AROUND THE LAKE AFTER
17Z. MUCH DRIER AIR ALOFT WILL THEN MOVE INTO SOUTH FLORIDA ON
TUESDAY WITH FORECAST SOUNDINGS SHOWING PWAT DROPPING TO LESS THAN
1.25 INCHES WITH THE NORTHEAST STEERING FLOW CONTINUING SO ONLY
ISOLATED OR LOW END SCATTERED IS EXPECTED ACROSS THE INTERIOR AND
SOUTHWEST COAST TUESDAY AFTERNOON/EVENING. THEY DRYING TREND WILL
PERSIST INTO WEDNESDAY ALTHOUGH FORECAST SOUNDINGS DO SHOW A
SLIGHT RETURN OF MOISTURE WITH PWAT CLIMBING BACK TO OVER 1.5
INCHES BY LATE IN THE DAY. STILL, NOT MUCH COVERAGE IS ANTICIPATED
WITH A MORE SOUTHEAST STEERING FLOW PATTERN RETURNING SO STORMS
WOULD TEND TO FORM INLAND FROM THE EAST COAST AND BE CONCENTRATED
OVER THE INTERIOR ONLY.
LONG TERM (THURSDAY-SUNDAY)...
AS CRISTOBAL EXITS TO THE NORTHEAST, A DEEP LAYER RIDGE WILL BUILD
BACK TO THE NORTH LATE THIS WEEK INTO THE UPCOMING WEEKEND WITH AN
INCREASE IN MOISTURE AND PWATS RETURNING TO NEAR NORMAL VALUES. THIS
WOULD CONTINUE TO STEER THE STORMS AWAY FROM THE EAST COAST TO THE
INTERIOR AND WEST COAST REGIONS. NO OTHER TROPICAL SYSTEMS ARE
EXPECTED TO AFFECT SOUTH FLORIDA THROUGH THE EXTENDED PERIOD.
MARINE...
NORTHEAST WINDS WILL PREVAIL THROUGH MIDWEEK, STRENGTHENING A TAD
TODAY AND TUESDAY AS THE PRESSURE GRADIENT TIGHTENS. THIS WILL
LEAD TO INCREASING SEAS ESPECIALLY IN THE GULF STREAM OFF THE PALM
BEACH COAST...WHERE HAZARDOUS SEAS OF 7+ FT ARE POSSIBLE DUE TO
FLOW COUNTERACTING THE GULF STREAM CURRENT ALONG WITH AN INCOMING
SMALL NORTHEAST SWELL.
&&
.PRELIMINARY POINT TEMPS/POPS...
WEST PALM BEACH 91 80 91 79 / 40 20 10 10
FORT LAUDERDALE 91 81 92 81 / 40 20 10 10
MIAMI 89 80 91 79 / 60 20 10 10
NAPLES 92 78 93 77 / 60 30 20 20
&&
.MFL WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
AM...NONE.
GM...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS MIAMI FL
749 AM EDT MON AUG 25 2014
.AVIATION...
SURFACE FLOW SHOULD REMAIN NORTHERLY THROUGH THE MORNING TO
NORTHEAST BY THE AFTERNOON. A SURGE OF ASSOCIATED MOISTURE WILL
KEEP ISOLATED TO SCATTERED SHOWERS PUSHING SOUTH ACROSS THE
ATLANTIC WATERS THROUGH THE MORNING. A FEW OF THESE SHOWERS MAY
MAKE IT INTO KFXE SOUTHWARD. THEREFORE KEPT VCSH AT THESE
TERMINALS THROUGH THE REMAINDER OF THE MORNING. OTHERWISE...VFR
CONDITIONS ARE EXPECTED OUTSIDE OF ANY AFTERNOON CONVECTION.
&&
.PREV DISCUSSION... /ISSUED 256 AM EDT MON AUG 25 2014/
SHORT TERM (TODAY-WEDNESDAY)...
IT CONTINUES TO LOOK MORE FAVORABLE THAT T.S. CRISTOBAL WILL MOVE
NORTH AND NORTHEAST AWAY FROM SOUTH FLORIDA. SO THE PRIMARY IMPACTS
WILL BE AN INCREASE IN RIP CURRENTS AT THE ATLANTIC BEACHES AND
BUILDING SEAS IN THE ATLANTIC FOR MARINE INTERESTS AS A SMALL
NORTHEAST SWELL IS GENERATED. MODELS SUGGEST A MOISTURE SURGE MOVING
INTO THE REGION AFTER 12Z THIS MORNING WHICH IS A RESULT IN THE
NORTHEAST CIRCULATION DEVELOPING WITH CRISTOBAL. THE CURRENT PWAT IS
AROUND 1.75 INCHES WITH FORECAST SOUNDINGS SHOWING AN INCREASE TO 2+
INCHES THIS MORNING. THE STEERING FLOW WILL BE NORTHEAST TO
SOUTHWEST SO THE EAST COAST COULD GET A QUICK PASSING SHRA/TSRA WITH
THE GREATEST ACTIVITY BEING OVER THE INTERIOR AND SOUTHWEST COAST.
THE HRRR IS SHOWING SOMETHING VERY SIMILAR WITH SCATTERED SHOWERS
NEAR THE EAST COAST WITH A FLARE UP INLAND AROUND THE LAKE AFTER
17Z. MUCH DRIER AIR ALOFT WILL THEN MOVE INTO SOUTH FLORIDA ON
TUESDAY WITH FORECAST SOUNDINGS SHOWING PWAT DROPPING TO LESS THAN
1.25 INCHES WITH THE NORTHEAST STEERING FLOW CONTINUING SO ONLY
ISOLATED OR LOW END SCATTERED IS EXPECTED ACROSS THE INTERIOR AND
SOUTHWEST COAST TUESDAY AFTERNOON/EVENING. THEY DRYING TREND WILL
PERSIST INTO WEDNESDAY ALTHOUGH FORECAST SOUNDINGS DO SHOW A
SLIGHT RETURN OF MOISTURE WITH PWAT CLIMBING BACK TO OVER 1.5
INCHES BY LATE IN THE DAY. STILL, NOT MUCH COVERAGE IS ANTICIPATED
WITH A MORE SOUTHEAST STEERING FLOW PATTERN RETURNING SO STORMS
WOULD TEND TO FORM INLAND FROM THE EAST COAST AND BE CONCENTRATED
OVER THE INTERIOR ONLY.
LONG TERM (THURSDAY-SUNDAY)...
AS CRISTOBAL EXITS TO THE NORTHEAST, A DEEP LAYER RIDGE WILL BUILD
BACK TO THE NORTH LATE THIS WEEK INTO THE UPCOMING WEEKEND WITH AN
INCREASE IN MOISTURE AND PWATS RETURNING TO NEAR NORMAL VALUES. THIS
WOULD CONTINUE TO STEER THE STORMS AWAY FROM THE EAST COAST TO THE
INTERIOR AND WEST COAST REGIONS. NO OTHER TROPICAL SYSTEMS ARE
EXPECTED TO AFFECT SOUTH FLORIDA THROUGH THE EXTENDED PERIOD.
MARINE...
NORTHEAST WINDS WILL PREVAIL THROUGH MIDWEEK, STRENGTHENING A TAD
TODAY AND TUESDAY AS THE PRESSURE GRADIENT TIGHTENS. THIS WILL
LEAD TO INCREASING SEAS ESPECIALLY IN THE GULF STREAM OFF THE PALM
BEACH COAST...WHERE HAZARDOUS SEAS OF 7+ FT ARE POSSIBLE DUE TO
FLOW COUNTERACTING THE GULF STREAM CURRENT ALONG WITH AN INCOMING
SMALL NORTHEAST SWELL.
&&
.PRELIMINARY POINT TEMPS/POPS...
WEST PALM BEACH 91 80 91 79 / 40 20 10 10
FORT LAUDERDALE 91 81 92 81 / 40 20 10 10
MIAMI 89 80 91 79 / 60 20 10 10
NAPLES 92 78 93 77 / 60 30 20 20
&&
.MFL WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
AM...NONE.
GM...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS MIAMI FL
256 AM EDT MON AUG 25 2014
.SHORT TERM (TODAY-WEDNESDAY)...
IT CONTINUES TO LOOK MORE FAVORABLE THAT T.S. CRISTOBAL WILL MOVE
NORTH AND NORTHEAST AWAY FROM SOUTH FLORIDA. SO THE PRIMARY IMPACTS
WILL BE AN INCREASE IN RIP CURRENTS AT THE ATLANTIC BEACHES AND
BUILDING SEAS IN THE ATLANTIC FOR MARINE INTERESTS AS A SMALL
NORTHEAST SWELL IS GENERATED. MODELS SUGGEST A MOISTURE SURGE MOVING
INTO THE REGION AFTER 12Z THIS MORNING WHICH IS A RESULT IN THE
NORTHEAST CIRCULATION DEVELOPING WITH CRISTOBAL. THE CURRENT PWAT IS
AROUND 1.75 INCHES WITH FORECAST SOUNDINGS SHOWING AN INCREASE TO 2+
INCHES THIS MORNING. THE STEERING FLOW WILL BE NORTHEAST TO
SOUTHWEST SO THE EAST COAST COULD GET A QUICK PASSING SHRA/TSRA WITH
THE GREATEST ACTIVITY BEING OVER THE INTERIOR AND SOUTHWEST COAST.
THE HRRR IS SHOWING SOMETHING VERY SIMILAR WITH SCATTERED SHOWERS
NEAR THE EAST COAST WITH A FLARE UP INLAND AROUND THE LAKE AFTER
17Z. MUCH DRIER AIR ALOFT WILL THEN MOVE INTO SOUTH FLORIDA ON
TUESDAY WITH FORECAST SOUNDINGS SHOWING PWAT DROPPING TO LESS THAN
1.25 INCHES WITH THE NORTHEAST STEERING FLOW CONTINUING SO ONLY
ISOLATED OR LOW END SCATTERED IS EXPECTED ACROSS THE INTERIOR AND
SOUTHWEST COAST TUESDAY AFTERNOON/EVENING. THEY DRYING TREND WILL
PERSIST INTO WEDNESDAY ALTHOUGH FORECAST SOUNDINGS DO SHOW A
SLIGHT RETURN OF MOISTURE WITH PWAT CLIMBING BACK TO OVER 1.5
INCHES BY LATE IN THE DAY. STILL, NOT MUCH COVERAGE IS ANTICIPATED
WITH A MORE SOUTHEAST STEERING FLOW PATTERN RETURNING SO STORMS
WOULD TEND TO FORM INLAND FROM THE EAST COAST AND BE CONCENTRATED
OVER THE INTERIOR ONLY.
.LONG TERM (THURSDAY-SUNDAY)...
AS CRISTOBAL EXITS TO THE NORTHEAST, A DEEP LAYER RIDGE WILL BUILD
BACK TO THE NORTH LATE THIS WEEK INTO THE UPCOMING WEEKEND WITH AN
INCREASE IN MOISTURE AND PWATS RETURNING TO NEAR NORMAL VALUES. THIS
WOULD CONTINUE TO STEER THE STORMS AWAY FROM THE EAST COAST TO THE
INTERIOR AND WEST COAST REGIONS. NO OTHER TROPICAL SYSTEMS ARE
EXPECTED TO AFFECT SOUTH FLORIDA THROUGH THE EXTENDED PERIOD.
&&
.MARINE...
NORTHEAST WINDS WILL PREVAIL THROUGH MIDWEEK, STRENGTHENING A TAD
TODAY AND TUESDAY AS THE PRESSURE GRADIENT TIGHTENS. THIS WILL
LEAD TO INCREASING SEAS ESPECIALLY IN THE GULF STREAM OFF THE PALM
BEACH COAST...WHERE HAZARDOUS SEAS OF 7+ FT ARE POSSIBLE DUE TO
FLOW COUNTERACTING THE GULF STREAM CURRENT ALONG WITH AN INCOMING
SMALL NORTHEAST SWELL.
&&
.PRELIMINARY POINT TEMPS/POPS...
WEST PALM BEACH 91 80 91 79 / 40 20 10 10
FORT LAUDERDALE 91 81 92 81 / 40 20 10 10
MIAMI 89 80 91 79 / 60 20 10 10
NAPLES 92 78 93 77 / 60 30 20 20
&&
.MFL WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
AM...NONE.
GM...NONE.
&&
$$
SHORT TERM...30/KOB
LONG TERM....30/KOB
AVIATION.....23/SK
AREA FORECAST DISCUSSION
NWS COLUMBIA SC
642 PM EDT MON AUG 25 2014
.SYNOPSIS...
HIGH PRESSURE RIDGING INTO THE FORECAST AREA FROM THE NORTH WILL
DIRECT DRY AIR INTO THE AREA THROUGH THE END OF THE WORK WEEK.
TEMPERATURES WILL BE NEAR NORMAL THROUGH TUESDAY...FOLLOWED BY A
WARMING TREND FOR THE LATTER HALF OF THE WEEK.
&&
.NEAR TERM /UNTIL 6 AM TUESDAY MORNING/...
A LARGE UPPER LEVEL RIDGE EXTENDED FROM THE SOUTHERN PLAINS TO
NEW ENGLAND WITH AN UPPER TROUGH WELL OFF THE EAST COAST. SURFACE
HIGH PRESSURE STRETCHED FROM THE NORTHEASTERN STATES ACROSS THE
CAROLINAS AND GEORGIA.
MOIST ONSHORE FLOW COULD BRING AN AREA OF CLOUDS ACROSS THE AREA
OVERNIGHT. AFTERNOON SATELLITE LOOP SHOWS SOME SCATTERED/BROKEN
AROUND 5K FT MOVING FROM THE PEE DEE INTO THE CENTRAL/EASTERN
MIDLANDS. BOTH THE RUC AND NAM INDICATE THIS MOISTURE. MODEL TIME
SECTIONS ALSO SHOW A 20 TO 25 KT LOW LEVEL JET AFTER MIDNIGHT AND
EXPECT THIS TO KEEP WINDS UP SLIGHTLY OVER LAND AND ALSO OVER THE
AREA LAKES. KEPT OVERNIGHT LOWS IN LINE WITH GUIDANCE...RANGING
THROUGH THE 60S GIVEN BOUNDARY LAYER MIXING AND PERIOD OF CLOUDS.
&&
.SHORT TERM /6 AM TUESDAY MORNING THROUGH TUESDAY NIGHT/...
HIGH PRESSURE BOTH AT THE SURFACE AND ALOFT WILL BE IN CONTROL
ACROSS THE REGION. THE AIR MASS WILL BE DRY WITH PWAT AT OR BELOW
ONE INCH. H850 TEMPERATURES WARM A COUPLE OF DEGREES...RESULTING
IN AFTERNOON HIGHS IN THE 85 TO 90 DEGREE RANGE UNDER SUNNY SKIES.
GOOD RADIATIONAL COOLING IN DRY AIR MASS WILL ALLOW TEMPERATURES
TO COOL INTO THE LOW TO MID 60S AS INDICATED BY GUIDANCE
CONSENSUS.
&&
.LONG TERM /WEDNESDAY THROUGH MONDAY/...
HIGH PRESSURE WILL REMAIN OVER THE AREA THROUGH FRIDAY AS AN UPPER
RIDGE BUILDS OVER THE SOUTHEAST. THE UPPER RIDGE WEAKENS A BIT OVER
THE WEEKEND AS LOW-LEVEL MOISTURE INCREASES...BUT THE RIDGE
STRENGTHENS AGAIN BY MONDAY. EXPECT A CHANCE OF SHOWERS AND
THUNDERSTORMS SATURDAY AND SUNDAY WITH A LESSER CHANCE MONDAY.
DAYTIME HIGH TEMPERATURES WILL INCREASE TO ABOVE NORMAL THROUGH
FRIDAY...AND NEAR NORMAL SATURDAY THROUGH MONDAY. OVERNIGHT LOW
TEMPERATURES WILL BE BELOW NORMAL WEDNESDAY AND THURSDAY...AND NEAR
NORMAL SATURDAY THROUGH MONDAY.
&&
.AVIATION /00Z TUESDAY THROUGH SATURDAY/...
HIGH PRESSURE RIDGING INTO THE AREA FROM THE NORTH WILL DOMINATE
THROUGH THE TAF PERIOD. MOISTURE FROM THE ATLANTIC IN THE
NORTHEAST FLOW WILL AFFECT THE REGION BUT EXPECT THE ASSOCIATED
CLOUDINESS WILL BE MAINLY SCATTERED AND BE AROUND 4000 FEET.
OBSERVATION TRENDS...THE GFS AND NAM MOS...AND THE SREF GUIDANCE
MAINTAIN VFR CONDITIONS. MIXING AND THE DRY NEAR-SURFACE LAYER
SHOULD HELP PREVENT FOG DURING THE EARLY MORNING HOURS. USED THE
GFS AND NAM MOS FOR THE WIND FORECAST.
EXTENDED AVIATION OUTLOOK...NO SIGNIFICANT IMPACTS EXPECTED.
&&
.CAE WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
GA...NONE.
&&
$$
77
AREA FORECAST DISCUSSION
NWS COLUMBIA SC
630 PM EDT MON AUG 25 2014
.SYNOPSIS...
HIGH PRESSURE RIDGING INTO THE FORECAST AREA FROM THE NORTH WILL
DIRECT DRY AIR INTO THE AREA THROUGH THE END OF THE WORK WEEK.
TEMPERATURES WILL BE NEAR NORMAL THROUGH TUESDAY...FOLLOWED BY A
WARMING TREND FOR THE LATTER HALF OF THE WEEK.
&&
.NEAR TERM /UNTIL 6 AM TUESDAY MORNING/...
A LARGE UPPER LEVEL RIDGE EXTENDED FROM THE SOUTHERN PLAINS TO
NEW ENGLAND WITH AN UPPER TROUGH WELL OFF THE EAST COAST. SURFACE
HIGH PRESSURE STRETCHED FROM THE NORTHEASTERN STATES ACROSS THE
CAROLINAS AND GEORGIA. WEAK COLD/DRY ADVECTION THIS AFTERNOON WITH
PWAT BELOW ONE INCH. SURFACE PRESSURE GRADIENT MODERATELY TIGHT SO
EXPECT SOME GUSTY NORTHEAST WINDS THIS AFTERNOON. TEMPERATURES
WILL BE SEASONABLE WITH HIGHS RANGING THROUGH THE 80S UNDER SUNNY
SKIES.
MOIST ONSHORE FLOW COULD BRING AN AREA OF CLOUDS ACROSS THE AREA
OVERNIGHT. BOTH THE RUC AND NAM INDICATE THIS MOISTURE. KEPT
OVERNIGHT LOWS IN LINE WITH GUIDANCE...RANGING THROUGH THE 60S
GIVEN BOUNDARY LAYER MIXING AND PERIOD OF CLOUDS.
&&
.SHORT TERM /6 AM TUESDAY MORNING THROUGH TUESDAY NIGHT/...
HIGH PRESSURE BOTH AT THE SURFACE AND ALOFT WILL BE IN CONTROL
ACROSS THE REGION. THE AIR MASS WILL BE DRY WITH PWAT AT OR BELOW
ONE INCH. H850 TEMPERATURES WARM A COUPLE OF DEGREES...RESULTING
IN AFTERNOON HIGHS IN THE 85 TO 90 DEGREE RANGE UNDER SUNNY SKIES.
GOOD RADIATIONAL COOLING IN DRY AIR MASS WILL ALLOW TEMPERATURES
TO COOL INTO THE LOW TO MID 60S AS INDICATED BY GUIDANCE
CONSENSUS.
&&
.LONG TERM /WEDNESDAY THROUGH MONDAY/...
HIGH PRESSURE WILL REMAIN OVER THE AREA THROUGH FRIDAY AS AN UPPER
RIDGE BUILDS OVER THE SOUTHEAST. THE UPPER RIDGE WEAKENS A BIT OVER
THE WEEKEND AS LOW-LEVEL MOISTURE INCREASES...BUT THE RIDGE
STRENGTHENS AGAIN BY MONDAY. EXPECT A CHANCE OF SHOWERS AND
THUNDERSTORMS SATURDAY AND SUNDAY WITH A LESSER CHANCE MONDAY.
DAYTIME HIGH TEMPERATURES WILL INCREASE TO ABOVE NORMAL THROUGH
FRIDAY...AND NEAR NORMAL SATURDAY THROUGH MONDAY. OVERNIGHT LOW
TEMPERATURES WILL BE BELOW NORMAL WEDNESDAY AND THURSDAY...AND NEAR
NORMAL SATURDAY THROUGH MONDAY.
&&
.AVIATION /00Z TUESDAY THROUGH SATURDAY/...
HIGH PRESSURE RIDGING INTO THE AREA FROM THE NORTH WILL DOMINATE
THROUGH THE TAF PERIOD. MOISTURE FROM THE ATLANTIC IN THE
NORTHEAST FLOW WILL AFFECT THE REGION BUT EXPECT THE ASSOCIATED
CLOUDINESS WILL BE MAINLY SCATTERED AND BE AROUND 4000 FEET.
OBSERVATION TRENDS...THE GFS AND NAM MOS...AND THE SREF GUIDANCE
MAINTAIN VFR CONDITIONS. MIXING AND THE DRY NEAR-SURFACE LAYER
SHOULD HELP PREVENT FOG DURING THE EARLY MORNING HOURS. USED THE
GFS AND NAM MOS FOR THE WIND FORECAST.
EXTENDED AVIATION OUTLOOK...NO SIGNIFICANT IMPACTS EXPECTED.
&&
.CAE WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
GA...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS COLUMBIA SC
318 PM EDT MON AUG 25 2014
.SYNOPSIS...
HIGH PRESSURE RIDGING INTO THE FORECAST AREA FROM THE NORTH WILL
DIRECT DRY AIR INTO THE AREA THROUGH THE END OF THE WORK WEEK.
TEMPERATURES WILL BE NEAR NORMAL THROUGH TUESDAY...FOLLOWED BY A
WARMING TREND FOR THE LATTER HALF OF THE WEEK.
&&
.NEAR TERM /UNTIL 6 AM TUESDAY MORNING/...
A LARGE UPPER LEVEL RIDGE EXTENDED FROM THE SOUTHERN PLAINS TO
NEW ENGLAND WITH AN UPPER TROUGH WELL OFF THE EAST COAST. SURFACE
HIGH PRESSURE STRETCHED FROM THE NORTHEASTERN STATES ACROSS THE
CAROLINAS AND GEORGIA. WEAK COLD/DRY ADVECTION THIS AFTERNOON WITH
PWAT BELOW ONE INCH. SURFACE PRESSURE GRADIENT MODERATELY TIGHT SO
EXPECT SOME GUSTY NORTHEAST WINDS THIS AFTERNOON. TEMPERATURES
WILL BE SEASONABLE WITH HIGHS RANGING THROUGH THE 80S UNDER SUNNY
SKIES.
MOIST ONSHORE FLOW COULD BRING AN AREA OF CLOUDS ACROSS THE AREA
OVERNIGHT. BOTH THE RUC AND NAM INDICATE THIS MOISTURE. KEPT
OVERNIGHT LOWS IN LINE WITH GUIDANCE...RANGING THROUGH THE 60S
GIVEN BOUNDARY LAYER MIXING AND PERIOD OF CLOUDS.
&&
.SHORT TERM /6 AM TUESDAY MORNING THROUGH TUESDAY NIGHT/...
HIGH PRESSURE BOTH AT THE SURFACE AND ALOFT WILL BE IN CONTROL
ACROSS THE REGION. THE AIR MASS WILL BE DRY WITH PWAT AT OR BELOW
ONE INCH. H850 TEMPERATURES WARM A COUPLE OF DEGREES...RESULTING
IN AFTERNOON HIGHS IN THE 85 TO 90 DEGREE RANGE UNDER SUNNY SKIES.
GOOD RADIATIONAL COOLING IN DRY AIR MASS WILL ALLOW TEMPERATURES
TO COOL INTO THE LOW TO MID 60S AS INDICATED BY GUIDANCE
CONSENSUS.
&&
.LONG TERM /WEDNESDAY THROUGH MONDAY/...
HIGH PRESSURE WILL REMAIN OVER THE AREA THROUGH FRIDAY AS AN UPPER
RIDGE BUILDS OVER THE SOUTHEAST. THE UPPER RIDGE WEAKENS A BIT OVER
THE WEEKEND AS LOW-LEVEL MOISTURE INCREASES...BUT THE RIDGE
STRENGTHENS AGAIN BY MONDAY. EXPECT A CHANCE OF SHOWERS AND
THUNDERSTORMS SATURDAY AND SUNDAY WITH A LESSER CHANCE MONDAY.
DAYTIME HIGH TEMPERATURES WILL INCREASE TO ABOVE NORMAL THROUGH
FRIDAY...AND NEAR NORMAL SATURDAY THROUGH MONDAY. OVERNIGHT LOW
TEMPERATURES WILL BE BELOW NORMAL WEDNESDAY AND THURSDAY...AND NEAR
NORMAL SATURDAY THROUGH MONDAY.
&&
.AVIATION /19Z MONDAY THROUGH SATURDAY/...
VFR CONDITIONS EXPECTED TO CONTINUE THROUGH THE 24-HOUR TAF
PERIOD. SURFACE HIGH PRESSURE CONTINUES BUILDING DOWN THE EASTERN
SEABOARD...COUPLED WITH AN UPPER RIDGE OVERHEAD. CLEAR SKIES THIS
AFTERNOON. MODELS INDICATE AN INCREASE IN CLOUDS 4-6KFT OVERNIGHT
IN MOIST ONSHORE FLOW.
NORTHEAST WINDS 10 TO 15 KNOTS WITH GUST NEAR 20 KNOTS THIS
AFTERNOON WILL DIMINISH WITH SUNSET.
EXTENDED AVIATION OUTLOOK...NO SIGNIFICANT IMPACTS TO AVIATION
EXPECTED.
&&
.CAE WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
GA...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS COLUMBIA SC
210 PM EDT MON AUG 25 2014
.SYNOPSIS...
HIGH PRESSURE RIDGING INTO THE FORECAST AREA FROM THE NORTH WILL
DIRECT DRY AIR INTO THE AREA THROUGH THE END OF THE WORK WEEK.
TEMPERATURES WILL BE NEAR NORMAL THROUGH TUESDAY...FOLLOWED BY A
WARMING TREND FOR THE LATTER HALF OF THE WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
A LARGE UPPER LEVEL RIDGE EXTENDED FROM THE SOUTHERN PLAINS TO
NEW ENGLAND WITH AN UPPER TROUGH WELL OFF THE EAST COAST. SURFACE
HIGH PRESSURE STRETCHED FROM THE NORTHEASTERN STATES ACROSS THE
CAROLINAS AND GEORGIA. WEAK COLD/DRY ADVECTION THIS AFTERNOON WITH
PWAT BELOW ONE INCH. SURFACE PRESSURE GRADIENT MODERATELY TIGHT SO
EXPECT SOME GUSTY NORTHEAST WINDS THIS AFTERNOON. TEMPERATURES
WILL BE SEASONABLE WITH HIGHS RANGING THROUGH THE 80S UNDER SUNNY
SKIES.
MOIST ONSHORE FLOW COULD BRING AN AREA OF CLOUDS ACROSS THE AREA
OVERNIGHT. BOTH THE RUC AND NAM INDICATE PWAT INCREASING TO NEAR
2.00 INCHES WITH AN INCREASE IN H850 MOISTURE. KEPT OVERNIGHT LOWS
IN LINE WITH GUIDANCE...RANGING THROUGH THE 60S GIVEN BOUNDARY LAYER
MIXING AND PERIOD OF CLOUDS.
&&
.SHORT TERM /TUESDAY THROUGH TUESDAY NIGHT/...
HIGH PRESSURE BOTH AT THE SURFACE AND ALOFT WILL BE IN CONTROL
ACROSS THE REGION. THE AIR MASS WILL BE DRY WITH PWAT AT OR BELOW
ONE INCH. H850 TEMPERATURES WARM A COUPLE OF DEGREES...RESULTING
IN AFTERNOON HIGHS IN THE 85 TO 90 DEGREE RANGE UNDER SUNNY SKIES.
GOOD RADIATIONAL COOLING IN DRY AIRMASS WILL ALLOW TEMPERATURES TO
COOL INTO THE LOW TO MID 60S AS INDICATED BY GUIDANCE CONSENSUS.
&&
.LONG TERM /WEDNESDAY THROUGH MONDAY/...
HIGH PRESSURE WILL REMAIN OVER THE AREA THROUGH FRIDAY AS AN UPPER
RIDGE BUILDS OVER THE SOUTHEAST. THE UPPER RIDGE WEAKENS A BIT OVER
THE WEEKEND AS LOW-LEVEL MOISTURE INCREASES...BUT THE RIDGE
STRENGTHENS AGAIN BY MONDAY. EXPECT A CHANCE OF SHOWERS AND
THUNDERSTORMS SATURDAY AND SUNDAY WITH A LESSER CHANCE MONDAY.
DAYTIME HIGH TEMPERATURES WILL INCREASE TO ABOVE NORMAL THROUGH
FRIDAY...AND NEAR NORMAL SATURDAY THROUGH MONDAY. OVERNIGHT LOW
TEMPERATURES WILL BE BELOW NORMAL WEDNESDAY AND THURSDAY...AND NEAR
NORMAL SATURDAY THROUGH MONDAY.
&&
.AVIATION /18Z MONDAY THROUGH SATURDAY/...
VFR CONDITIONS EXPECTED TO CONTINUE THROUGH THE 24 HOUR TAF PERIOD.
SURFACE HIGH PRESSURE CONTINUES BUILDING DOWN THE EASTERN
SEABOARD...COUPLED WITH AN UPPER RIDGE OVERHEAD. CLEAR SKIES THIS
AFTERNOON. MODELS INDICATE AN INCREASE IN CLOUDS 4-6KFT OVERNIGHT
IN MOIST ONSHORE FLOW.
NORTHEAST WINDS 10 TO 15 KNOTS WITH GUST NEAR 20 KNOTS THIS
AFTERNOON WILL DIMINISH WITH SUNSET.
EXTENDED AVIATION OUTLOOK...NO SIGNIFICANT IMPACTS TO AVIATION
EXPECTED.
&&
.CAE WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
GA...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS COLUMBIA SC
1135 AM EDT MON AUG 25 2014
.SYNOPSIS...
HIGH PRESSURE RIDGING INTO THE FORECAST AREA FROM THE NORTH WILL
DIRECT DRY AIR INTO THE AREA THROUGH MIDWEEK. TEMPERATURES WILL BE
NEAR NORMAL EARLY THIS WEEK THEN A WARMING TREND WILL DEVELOP FOR
MID-WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
A LARGE UPPER LEVEL RIDGE EXTENDED FROM THE SOUTHERN PLAINS TO
NEW ENGLAND WITH AN UPPER TROUGH WELL OFF THE EAST COAST. SURFACE
HIGH PRESSURE STRETCHED FROM THE NORTHEASTERN STATES ACROSS THE
CAROLINAS AND GEORGIA. WEAK COLD/DRY ADVECTION THIS AFTERNOON WITH
PWAT BELOW ONE INCH. SURFACE PRESSURE GRADIENT MODERATELY TIGHT SO
EXPECT SOME GUSTY NORTHEAST WINDS THIS AFTERNOON. TEMPERATURES
WILL BE SEASONABLE WITH HIGHS IN THE RANGING THROUGH THE 80S UNDER
SUNNY SKIES.
MOIST ONSHORE LOW COULD BRING AN AREA OF CLOUDS ACROSS THE AREA
OVERNIGHT. BOTH THE RUC AND NAM INDICATE PWAT INCREASING TO NEAR
2.00 INCHES WITH AN INCREASE IN 8H50 MOISTURE. KEPT OVERNIGHT LOWS
IN LINE WITH GUIDANCE...RANGING THROUGH THE 60S.
&&
.SHORT TERM /TUESDAY THROUGH WEDNESDAY/...
HIGH PRESSURE DOMINATES THROUGH THE PERIOD. AIR MASS REMAINS DRY.
UPPER RIDGE BUILDING EAST THROUGH THE PERIOD SO WARMING TREND
DEVELOPING.
&&
.LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/...
HIGH PRESSURE WILL REMAIN OVER THE AREA FOR MUCH OF THE WEEK.
LATEST MODELS SUGGEST FRONT REMAINING NORTH OF THE REGION FRIDAY
AND RIDGE OVER THE AREA SO BACKED OFF ON POPS. ANOTHER COLD FRONT
MOVING IN FROM THE WEST SUNDAY. FORECASTED LOW CHANCE POPS FRIDAY
THROUGH SUNDAY. TEMPERATURES NEAR OR JUST SLIGHTLY BELOW NORMAL
MONDAY THROUGH WEDNESDAY...AND A LITTLE ABOVE NORMAL FOR THE
REMAINDER OF THE EXTENDED PERIOD.
&&
.AVIATION /15Z MONDAY THROUGH FRIDAY/...
VFR CONDITIONS EXPECTED TO CONTINUE THROUGH THE 24 HOUR TAF PERIOD.
DRY HIGH PRESSURE BUILDING DOWN THE EASTERN SEABOARD...COUPLED WITH
AN UPPER RIDGE OVERHEAD...WILL ENSURE FAIR AND DRY WEATHER.
WINDS WILL BE NORTHEAST AROUND 10 KNOTS WITH GUST NEAR 20 KNOTS
THIS AFTERNOON.
EXTENDED AVIATION OUTLOOK...NO SIGNIFICANT IMPACTS TO AVIATION
EXPECTED.
&&
.CAE WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
GA...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
949 PM CDT TUE AUG 26 2014
.DISCUSSION...
255 PM CDT
AS HAS BEEN THE NORM IN THE PAST WEEK TO TEN DAYS...THE PRIMARY
FORECAST CHALLENGES ARE TRYING TO DETECT WHEN BETTER THUNDERSTORM
CHANCES MAY BE AND WHAT INFLUENCE THOSE HAVE...IF ANY...ON
TEMPERATURES.
.TONIGHT...
THE INITIAL SYNOPTIC COLD FRONT HAS APPEARED TO CLEAR THE
FORECAST AREA. THIS SURGE WAS CONVECTIVELY ENHANCED AND LINGERING
HIGH DEW POINT AIR...E.G. UPPER 60S TO LOWER 70S...REMAINS ACROSS
THE SOUTH. THERE ALSO ARE ONE OR TWO WESTWARD-PROPAGATING OUTFLOW
BOUNDARIES THAT ARE LIKELY TO LAST INTO LATE THIS AFTERNOON.
CUMULUS HAS FORMED NEAR PONTIAC AND GIBSON CITY...AND BACK TOWARD
PRINCETON TO MENDOTA...WITH THESE FEATURES. WOULD NOT BE TOTALLY
SURPRISED TO SEE ISOLATED STORMS POP ON THESE AS MIXED LAYER
INHIBITION APPEARS SHALLOW WITH RECOVERING TEMPERATURES INTO THE
MID 80S AND EVEN 88 AT PONTIAC. A COUPLE SUBTLE SHORT WAVES ARE
NOTED ON WATER VAPOR...WITH ONE A LITTLE BETTER DEFINED ON
VISIBLE SATELLITE NEARING THE MISSISSIPPI RIVER FROM IA ASSOCIATED
WITH A 35 KT 500MB SPEED MAXIMUM. THIS LOOKS TO PASS OVER NORTH
CENTRAL IL EARLY THIS EVE AND COULD SEE SOME SHOWER/STORM ACTIVITY
WITH THAT...ALTHOUGH CONFIDENCE IS LOW FOR SHORT TERM STORM
CHANCES...SO HAVE KEPT POPS FAIRLY LOW. CONFLUENT 700-850MB FLOW
CONTINUES OVERNIGHT WITH ANOTHER LITTLE RIPPLE IN THE FLOW
FORECAST TO MOVE OVER THE AREA. SO CONTINUE CHANCE FOR A STORM
THROUGH THE ENTIRE NIGHT...BUT NOT EXPECTING ANYTHING WIDESPREAD.
INCOMING CLOUDS FROM THE DISTURBED MID-LEVEL FLOW SHOULD KEEP THE FOG
THREAT MINIMAL...AND TEMP/DEW POINT SPREADS LOOK TO BE MODESTLY
HIGH GOING INTO TONIGHT IN MOST AREAS...OUTSIDE OF THE FAR SOUTH.
MTF
.WEDNESDAY THROUGH TUESDAY...
THE LONGWAVE PATTERN OVER THE CENTRAL CONUS HAS BECOME MORE ZONAL
WITH TROPICAL SYSTEM OVER SERN ATLANTIC...NERN PACIFIC WHILE A BROAD
HIGH SITS OVER THE SRN CONUS AND A CLOSED UPPER LOW SWINGS THROUGH
THE GREAT BASIN. THE SENSIBLE WEATHER OVER THE CWA WILL CONTINUE TO
BE UNSETTLED AS A STRONG SHORTWAVE QUICKLY MOVES ACROSS THE UPPER
MISSISSIPPI VALLEY AND GREAT LAKES WEDNESDAY. UPPER RIDGING SHOULD
BUILD ACROSS THE MIDWEST ON THURSDAY AS MORE SHORT WAVE ENERGY
OVERTOPS THE RIDGE AND TRACKS ACROSS THE UPPER MIDWEST AND THE LOWER
GREAT LAKES REGIONS. BY THURSDAY NIGHT AND FRIDAY...THE UPPER RIDGE
SHOULD BUILD TO THE EAST OF THE REGION AS THE UPPER LOW OVER THE
GREAT BASIN FINALLY OPENS UP AND LIFTS EAST ACROSS THE CENTRAL
PLAINS AS AN OPEN WAVE FRIDAY AND FRIDAY NIGHT. THIS WAVE WILL
CROSS THE UPPER MIDWEST INTO THE WESTERN GREAT LAKES BY SUNDAY. THE
LONGER RANGE GUIDANCE SUGGESTS THAT THIS WAVE WILL PHASE WITH
ANOTHER NORTHERN STREAM SHORTWAVE OVER THE UPPER GREAT LAKES BY
SUNDAY. THE PROGRESSIVE AND RELATIVELY LOW AMPLITUDE UPPER LEVEL
PATTERN OVER THE CONUS WILL LEAD TO A CONTINUES ACTIVE WEATHER
PATTERN FOR THE LOCAL AREA...WITH PERIODIC CHANCES FOR SHOWERS AND
THUNDERSTORMS THROUGH MUCH OF THE PERIOD. THE SOUTHERN PORTIONS OF
THE CWA WILL BE MORE FAVORABLE FOR ADDITIONAL PCPN WEDNESDAY AS SFC
HIGH PRESSURE SPREADS ACROSS THE GREAT LAKES REGION AND THE OLD
FRONTAL BOUNDARY LAYS OUT ALONG THE OHIO VALLEY INTO SRN ILLINOIS.
AS A SFC LOW DEEPENS OVER THE CENTRAL PLAINS ON THURSDAY...IT WILL
DRAG THE FRONT NORTH AGAIN AS A WARM FRONT...BRINGING GREATER
CHANCES FOR MORE WIDESPREAD PCPN TO THE AREA FOR THURSDAY AND
THURSDAY NIGHT. WHILE THE FRONT REMAINS TO THE SOUTH AND HIGH
PRESSURE SPREADS ACROSS THE GREAT LAKES REGION...TEMPERATURES WILL
DIP BACK INTO THE MIDDLE 70S ACROSS THE NORTHERN PORTIONS OF THE CWA
WHILE THE SOUTHERN LOCATIONS MAY REACH THE LOWER 80S. BY
FRIDAY...WHEN THE WARM FRONT LIFTS NORTH OF THE CWA...HOT AND HUMID
CONDITIONS WILL RETURN...WITH HIGHS IN THE MIDDLE 80S...DEWPOINTS IN
THE LOWER 70S AND MAX HEAT INDEX VALUES INTO THE LOWER 90S. THE
DEVELOPING SFC LOW IS EXPECTED TO SLOWLY LIFT ACROSS THE UPPER
MISSISSIPPI VALLEY ON SATURDAY...KEEPING THE LOCAL AREA UNDER WARM
SECTOR AIR AHEAD OF AN ASSOCIATED COLD FRONT. WHILE THE AREA
REMAINS IN THE WARM SECTOR THROUGH THE WEEKEND...THERE WILL CONTINUE
TO BE CHANCES FOR SCATTERED SHOWERS AND THUNDERSTORMS...BUT WITHOUT
A STRONG FOCUSING MECHANISM...WILL KEEP POPS IN THE CHANCE RANGE.
BY EARLY NEXT WEEK...THE LONG RANGE GUIDANCE IS SUGGESTING THAT THE
COLD FRONT SHOULD FINALLY PUSH THROUGH THE AREA...BUT THERE SHOULD
BE LITTLE IN THE WAY OF AIRMASS CHANGE WITH THE FROPA AS ANOTHER
DEEPENING TROUGH OVER THE NORTHERN PLAINS SHOULD QUICKLY BRING A
RETURN TO WARM...MOIST SOUTHERLY FLOW FOR EARLY NEXT WEEK...WHICH
WILL...IN TURN...KEEP CONTINUES CHANCES FOR PCPN ACROSS THE REGION.
KREIN
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 03Z...
* EAST-NORTHEASTERLY WIND SPEEDS WEDNESDAY AFTERNOON...POSSIBLY
NEAR 10 KT IN THE AFTERNOON.
KJB
//DISCUSSION...UPDATED 00Z...
A LAKE BREEZE IS CURRENTLY MOVING OVER THE EASTERN TERMINALS.
HOWEVER...WIND SPEEDS ARE GENERALLY LESS THAN 8 KT WITH THE
NORTHEASTERLY PUSH. WEATHER CONCERNS AT THE TERMINALS OVER THE NEXT
24 HOURS LOOK TO MAINLY REVOLVE AROUND THE MAGNITUDE OF THE
NORTHEASTERLY WINDS...ESPECIALLY WEDNESDAY AFTERNOON. THE MAIN
THREAT FOR THUNDERSTORMS ON WEDNESDAY LOOKS TO REMAIN SOUTH OF THE
TERMINALS. IT APPEARS THE NORTHEASTERLY WINDS WILL GENERALLY REMAIN
UNDER 10 KT...ESPECIALLY DURING THE MORNING. HOWEVER...WIND SPEEDS
COULD GET TO OR JUST SLIGHTLY ABOVE 10 KT FOR A FEW HOURS TOMORROW
AFTERNOON AS A LAKE BREEZE PUSH COULD LOCALLY ENHANCE WIND SPEEDS A
BIT.
KJB
//ORD AND MDW CONFIDENCE...UPDATED 03Z...
* HIGH WITH ALL FORECAST ELEMENTS.
KJB
//OUTLOOK FOR ORD/MDW FOR 12Z THURSDAY-12Z TUESDAY...UPDATED 00Z...
* THURSDAY THROUGH MONDAY...CHANCE OF TSRA.
KJB
&&
.MARINE...
250 PM CDT
LOW PRESSURE CONTINUES TO TRACK OUT OF NORTHERN QUEBEC AS A TRAILING
COLD FRONT EXTENDS SOUTHWEST THROUGH NORTHERN INDIANA AND INTO
SOUTHERN ILLINOIS. THE FRONT SHOULD STALL OUT OVER THE OHIO VALLEY
OVERNIGHT TONIGHT AND HIGH PRESSURE BUILDS ACROSS UPPER MISSISSIPPI
VALLEY AND WESTERN GREAT LAKES. WINDS OVER THE LAKE HAVE BEEN
DISRUPTED BY THUNDERSTORM ACTIVITY TODAY...BUT SHOULD SETTLE INTO A
MORE NORTHERLY TO NORTHEASTERLY DIRECTION OVERNIGHT TONIGHT. THE
HIGH IS EXPECTED TO BUILD ACROSS THE UPPER GREAT LAKES WEDNESDAY
NIGHT WHILE LOW PRESSURE DEEPENS OVER THE CENTRAL PLAINS. WINDS
OVER THE NORTHERN PORTIONS OF THE LAKE SHOULD THEN BECOME SOMEWHAT
VARIABLE IN DIRECTION AS THE CENTER OF THE HIGH MOVES OVER THE FAR
NORTHERN PORTION OF THE LAKE...BUT THE SOUTHERN PORTIONS OF THE LAKE
SHOULD MAINTAIN A NORTHEASTERLY TO EASTERLY FETCH. THE PERSISTENT
NORTHEASTERLY TO EASTERLY FETCH SHOULD CAUSE WINDS TO PILE UP OVER
THE WESTERN SHORE OF THE LAKE...APPROACHING 3-4FT AS WINDS REACH
10-20KT. THE HIGH WILL CONTINUE TO BUILD TO THE EAST THURSDAY AND
FRIDAY AS LOW PRESSURE TRACKS NEWD ONTO THE UPPER MISSOURI VALLEY.
THIS WILL...IN TURN...LIFT THE OLD FRONTAL BOUNDARY THAT HAD GONE
STATIONARY OVER THE OHIO VALLEY TO LIFT NORTH AS A WARM FRONT TURING
WINDS THROUGH SOUTHEASTERLY TO SOUTHERLY BY FRIDAY.
AS HAS BEEN THE NORM IN THE PAST WEEK TO TEN DAYS...THE PRIMARY
FORECAST CHALLENGES ARE MUCH WHAT THEY HAVE BEEN...TRYING TO DETECT
WHEN BETTER THUNDERSTORM CHANCES MAY BE AND WHAT INFLUENCE THOSE
CONVECTIVE CHANCES HAVE ON TEMPERATURES.
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
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[top]
Area Forecast Discussion
NATIONAL WEATHER SERVICE LINCOLN IL
848 PM CDT Tue Aug 26 2014
.UPDATE...
ISSUED AT 845 PM CDT TUE AUG 26 2014
Band of strong/severe storms has been slowly trudging southward
along the frontal boundary roughly along the the I-72 corridor.
The models are generally handling this convection extremely
poorly, although the 21Z online HopWRF is doing a pretty decent
job, with the NamDNG5 also in the general vicinity. The HopWRF
shows a general push toward the I-70 corridor over the next couple
hours, and there is a lingering outflow that extends from near
Flora northwest toward Taylorville, so that could feed some
additional development. The front will not be moving too much
overnight, and the RAP and 18Z NAM show some redevelopment north
of it after 2-3am.
Have sent some updated grids/zones to significantly increase the
PoP`s this evening with this convection. Have not looked too
closely at the temperatures yet, so further updates may be needed
once that is evaluated.
&&
.SHORT TERM...(This evening through Wednesday)
ISSUED AT 316 PM CDT TUE AUG 26 2014
An outflow boundary is draped over the area this afternoon and this
could be the focus for more showers and thunderstorm development
this evening and into tonight. So will be keeping a chance pops in
the forecast for tonight, but mainly along and northeast of I-74. By
tomorrow, all models indicate a good chance of thunderstorms across
most of the area through tomorrow afternoon. Things will then shift
back to the west after that.
Temps and dew points are remaining high so will keep the heat
advisory and warning going through this evening. Temps will remain
warm through tomorrow, but with clouds and pcpn, advisory/warning
criteria for heat indices will not be met. Model guidance numbers
look to be too warm.
&&
.LONG TERM...(Wednesday night through Tuesday)
ISSUED AT 316 PM CDT TUE AUG 26 2014
Upper level ridging will be broken down, which will allow another
cold front to move into the area late in the week. Unfortunately
this means that the chance of showers and thunderstorms will
continue into the weekend. Most of the pcpn chances will remain to
the northwest or northern part of the CWA through Friday. Then when
the front drops into the area Friday afternoon, the chance of
thunderstorms will spread across the whole CWA for most of the
weekend. There could be a break in the pcpn over some of the area
Sunday night, but another frontal system will move into the region
for the beginning of next week...so chance pops continue.
Temps will cool through the period, but then warm back up during the
beginning of next week. Model guidance still looks to be too warm.
&&
.AVIATION...(For the 18Z TAFS through 18Z Wednesday afternoon)
ISSUED AT 1241 PM CDT TUE AUG 26 2014
Not much of a shift in the forecast for this round of TAFs.
Main concern remains the front...which is still to the northwest.
Slight wind shift over the region right now due to outflow from
this mornings thunderstorms across the north. Front moving through
the region later tonight/this evening to stall and slow through
the early morning hours resulting in an extended period of
potential thunder, esp with wave moving out of the west. Models
with many solutions and potential of thunder. Concern for vis drop
just behind the boundary if clearing is ahead of the drier air. So
far, leaving that out of the forecast, but may need to be worked
into the next issuance.
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...GEELHART
SHORT TERM...HJS
LONG TERM...AUTEN
AVIATION...HJS
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
317 PM CDT MON AUG 25 2014
.DISCUSSION...
315 PM CDT
SHORT TERM...THROUGH EARLY TUESDAY MORNING...
FOR THE REMAINDER OF THE AFTERNOON...MAIN FOCUS WILL CONTINUE TO BE
2 LINES OF THUNDERSTORMS...ONE MOVING THROUGH NWRN IL AND ANOTHER
MOVING THROUGH NWRN IN AND ECNTRL IL. THESE LINES ARE PRODUCING
STRONG TO OCNLY SVR TS...WITH THE PRIMARY THREAT BEING WIND GUSTS
TO 60 MPH AND TORRENTIAL DOWNPOURS. THE TREND WITH TIME SHOULD BE
FOR THE LINE OVER NWRN IL TO BEGIN TO WEAKEN AS IT MOVES INTO AN
AIRMASS OVER NERN IL WHICH HAS BEEN WORKED OVER BY EARLIER
CONVECTION. THE LINE ACROSS NWRN IN INTO ECNTRL IL SHOULD MAINTAIN
SOME STRENGTH AS IT CONTINUES TO PUSH SEWD. LATEST RADAR IMAGERY
SHOWS A DISTINCT OUTFLOW BOUNDARY EXTENDING WEST FROM KANKAKEE TO
PERU WHICH COULD YET BE THE FOCUS FOR SOME ADDITIONAL THUNDERSTORM
DEVELOPMENT INTO THE EARLY EVENING HOURS. THUNDERSTORMS HAVE HAD A
HISTORY OF PRODUCING IN EXCESS OF 1 INCH IN 30 MINUTES...BUT SINCE
THEY HAVE BEEN PROGRESSIVE...SIGNIFICANT WIDESPREAD FLOODING IS NOT
ANTICIPATED...THOUGH LOCALLY HEAVY RAINFALL COULD PRODUCE URBAN ANS
SMALL STREAM TYPE FLOODING. EXPECT THAT THE POTENTIAL FOR ORGANIZED
THUNDERSTORMS SHOULD DIMINISH INTO EARLY THIS EVENING WITH THE
SETTING SUN AND LARGER SCALE SUBSIDENCE MOVES OVER THE AREA AS WEAK
SHORT WAVE RIDGING MOVES OVER THE AREA TONIGHT. AS THE THUNDERSTORM
ACTIVITY DIMINISHES THIS EVENING...PATCHY FOG AND WIDESPREAD
MISTY/MURKY CONDITIONS WILL SET UP. WHILE WIDESPREAD DENSE FOG IS
NOT LIKELY DUE TO PERSISTENT DEBRIS CLOUD FROM EARLIER
CONVECTION...A VERY MOIST ENVIRONMENT WILL REMAIN IN PLACE...AND
COMBINED WITH LIGHT WINDS CONDITIONS WILL REMAIN MUGGY OVERNIGHT.
THE TEMPERATURE FORECAST FOR TODAY WAS DISRUPTED BY THE THUNDERSTORMS
AND EXTENSIVE CLOUD COVER OVER AREAS IMPACTED BY THE THUNDERSTORMS.
HOWEVER...LOCATIONS SOUTH OF A LINE FROM MIDWAY AIRPORT TO PERU
STILL SAW MAX HEAT INDICES IN EXCESS OF 100F WHILE LOCATIONS SOUTH
OF THE ILLINOIS/KANKAKEE RIVERS SAW HEAT INDICES APPROACH OR SLIGHTLY
EXCEED 110F. TEMPERATURES AND DEWPOINTS SHOULD REMAIN IN THE LOWER
TO MIDDLE 70S OVERNIGHT AS THERE WILL BE NO SGFNT CHANGE IN
AIRMASS. WITH OLD OUTFLOW BOUNDARIES HANGING AROUND THE AREA
OVERNIGHT...THERE WILL STILL BE SOME LOW CHANCES FOR ADDITIONAL
SHOWERS OR THUNDERSTORMS AS A WEAK COLD FRONT MOVES DOWN THE LAKE
AND INTO THE WARM...HUMID ENVIRONMENT.
KREIN
LONG TERM DISCUSSION COMING SOON...
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 20Z...
* WINDS TURNING NE ARND 10-12KT...WITH AN OCCASIONAL GUSTS TO
20-25KT.
* WIND SPEEDS DIMINISH TO ARND 6-8KT LATE AFTN/EARLY EVE...THEN
TURN W/NW.
* POSSIBLE ADDTL ISOLATED TSRA OVERNIGHT/EARLY TUE MORNING.
* PATCHY FOG DEVELOPING AFT 04Z...MAY REDUCE VSBYS TO ARND 2-4SM.
WEST OF TAF SITES VSBYS COULD BE LOWER.
BEACHLER
//DISCUSSION...UPDATED 18Z...
SPOTTY SHOWERS AND THUNDERSTORMS HAVE CONTINUED TO DEVELOP ALONG
AN ORIGINAL OUTFLOW BOUNDARY ACROSS NORTHEAST IL. ADDTL SHRA/TSRA
HAVE DEVELOPED WEST OF TAF SITES...WITH A FEW STRONGER STORMS
CAPABLE OF PRODUCING WIND GUSTS TO 40KTS THIS AFTN. CONCERN IS
THAT A WEAK BOUNDARY SLIDING SOUTH AND A LACK OF A GRADIENT...WILL
ONLY PROLONG THE NORTHEAST WINDS AT ORD/MDW. MEANWHILE FURTHER
WEST AT RFD/DPA THE WINDS SHUD BE ABLE TO TURN NW/W ARND 20-21Z.
WILL CONTINUE TO MENTION VCTS THRU 23Z...AND IF ADDTL STORMS ARE
ABLE TO DEVELOP WE WILL LIKELY NEED TO ADJUST WITH A TEMPO BUT
COVERAGE IS NOT EXPECTED TO BE THERE. THEN LATE THIS EVENING
GUIDANCE IS SUGGESTING THE WINDS WILL BECOME LGT FROM THE NW ARND
5-8KT. THE CONCERN THEN WILL TURN TOWARDS THE LOW CIGS BUT ALSO
THE POTENTIAL FOR PATCHY FOG TO DEVELOP GIVEN HOW MOIST THE
ENVIRONMENT WILL REMAIN OVERNIGHT. FOG MAY BEGIN TO DISSIPATE AFT
DAYBREAK TUE...THEN GUIDANCE SUGGESTS THE WINDS WILL TRY TO TURN
NW WITH SPEEDS ARND 8-11KT.
BEACHLER
//ORD AND MDW CONFIDENCE...UPDATED 20Z...
* HIGH CONFIDENCE IN TSRA REMAINING ISOLATED...LOW CONFIDENCE IN
PRECISE TIMING/INTENSITY AT TAF SITES.
* HIGH CONFIDENCE IN WINDS REMAINING NORTHEAST THRU 22Z...THEN LOW
CONFIDENCE IN TIMING OF WINDS TURNING NW LATE AFTN/EARLY EVE.
* MEDIUM CONFIDENCE IN PATCHY FOG DEVELOPING.
BEACHLER
//OUTLOOK FOR ORD/MDW FOR 00Z WEDNESDAY-12Z MONDAY...UPDATED 12Z...
* TUESDAY NIGHT...TSRA LIKELY.
* WEDNESDAY THROUGH SUNDAY...CHANCE OF TSRA.
&&
.MARINE...
243 AM...LOW PRESSURE OVER SOUTHERN MANITOBA WILL MOVE ACROSS
NORTHERN ONTARIO TODAY AND TONIGHT REACHING JAMES BAY TUESDAY
MORNING. A TRAILING COLD FRONT WILL SLOWLY SAG SOUTHEAST ACROSS
THE WESTERN LAKES AND REACH NORTHERN LAKE MICHIGAN BY DAYBREAK
TUESDAY MORNING. THIS FRONT WILL THEN CONTINUE SOUTH ACROSS LAKE
MICHIGAN TUESDAY AND EVENTUALLY STALL NEAR OR JUST SOUTH OF THE
LAKE WEDNESDAY INTO THURSDAY. AHEAD OF THIS FRONT...SOUTH TO
SOUTHEAST WINDS 10-20KTS WILL GRADUALLY SHIFT MORE SOUTHWESTERLY
LATER TODAY AND THIS EVENING. A FEW HIGHER GUSTS ARE POSSIBLE BUT
THE TIGHTEST PORTION OF THE GRADIENT PASSES NORTH OF THE LAKE.
HIGH PRESSURE WILL BUILD ACROSS THE NORTHERN PLAINS ON TUESDAY
AND THEN MOVE ACROSS THE NORTHERN LAKES WEDNESDAY. THIS MAY
STRENGTHEN THE GRADIENT A BIT ON THE SOUTHERN END OF THE LAKE
WITH A PROLONGED NORTHEAST FLOW IN THE 10-20KT RANGE POSSIBLE.
CMS
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...HEAT ADVISORY...ILZ010-ILZ019-ILZ021-ILZ023-ILZ032-ILZ033-ILZ039
UNTIL 10 PM MONDAY.
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
314 PM CDT Mon Aug 25 2014
.SHORT TERM...(This evening through Tuesday)
ISSUED AT 312 PM CDT MON AUG 25 2014
Hot and very humid conditions are the rule across central Illinois
this afternoon, with 19z/2pm temperatures in the lower to middle 90s
across the board. Further north, clusters of thunderstorms have
developed along outflow boundaries from eastern Iowa across
northern Illinois. This convection is generally tracking eastward,
with a slight southeastward drift. High-res models are once again
handling the convection quite poorly, with the 2-hr HRRR forecast
completely missing the storms currently ongoing south of Chicago.
The Chicago storm complex will continue developing E/SE into
northwest Indiana over the next couple of hours. Meanwhile, we will
have to keep an eye on additional storms just north of Moline.
These cells will likely track E/SE along an outflow boundary evident
on satellite/radar imagery and should remain just north of the KILX
CWA. Have included a slight chance PoP along/northeast of a Henry
to Danville late this afternoon into the early evening in case they
develop a bit further southward.
A cold front currently analyzed across central Iowa will gradually
push eastward over the next 12 to 24 hours, reaching the northern
KILX CWA by Tuesday morning. Many of the 12z models show little or
no convection with the boundary overnight, but have included low
chance PoPs along/northwest of a Rushville to Bloomington line as
the front encounters a very moist airmass. Aside from any scattered
convection that may develop, the potential for fog will once again
be an issue overnight. Light/variable winds along with dewpoint
pooling along the boundary will favor fog, but increased mid/high
clouds may tend to mitigate it somewhat. Based on an unchanged
airmass and persistence from the past several nights, have included
patchy fog in the forecast after midnight.
Any fog will dissipate early Tuesday morning, followed by partly to
mostly sunny conditions across the southern half of the CWA.
Further north in closer proximity to the nearly stationary frontal
boundary, mostly cloudy skies and scattered convection will keep
temps slightly cooler than they have been recently. High temps on
Tuesday will range from the upper 80s north to the middle 90s
along/south of I-70. Due to the slightly cooler temps, heat index
readings across the north may not reach advisory criteria. May need
to drop the advisory for the Peoria area northward, as heat index
values will likely remain in the 95 to 100 degree range on Tuesday.
&&
.LONG TERM...(Tuesday night through Monday)
ISSUED AT 312 PM CDT MON AUG 25 2014
A frontal boundary will become somewhat stationary over the area and
is forecast to remain there through the rest of the week and into
the weekend. This will become the focus for thunderstorms throughout
the period. Thunderstorms will not be continuous throughout the
period, but trying to time when the dry, or drier, periods is going
to be is the main forecast challenge. Due to the difficulty of
timing the precip periods and the dry periods during the medium and
long ranges of the forecast, best to just have chance pcpn through
the period over the whole area. Will have likely pops in the north
third of the CWA for Tue night, but remainder of the forecast will
just be chance across the area.
With the frontal boundary getting into the area, relatively cooler
air will advect into the area. Temperatures will gradually drop back
to around normal, which is middle to upper 80s, by the weekend.
However, with all the moisture forecasted over the area, muggy/humid
conditions will continue through the period.
&&
.AVIATION...(For the 18Z TAFS through 18Z Tuesday afternoon)
ISSUED AT 1248 PM CDT MON AUG 25 2014
Mostly sunny skies will prevail across central Illinois today, as
convection remains along/north of the I-80 corridor. Latest
satellite imagery shows clear skies across much of the area, with
just FEW-SCT diurnal clouds developing near KBMI and KCMI. Cold
front currently analyzed across central Iowa will drop
southeastward tonight, eventually settling into north-central
Illinois by Tuesday morning. With boundary approaching, winds will
go light/variable, once again setting up the potential for fog
overnight. Forecast soundings and numeric guidance support fog
development, so have included reduced visbys of 3 to 5 miles
between 08z and 14z. Am not expecting much in the way of
thunderstorm development through 18z, although have introduced a
mid-level cloud deck at KPIA as the front arrives late tonight
into Tuesday morning.
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
EXCESSIVE HEAT WARNING until 7 PM CDT Tuesday FOR ILZ042-047>054-
056-061>063-066>068-071>073.
HEAT ADVISORY until 7 PM CDT Tuesday FOR ILZ027>031-036>038-040-
041-043>046-055-057.
&&
$$
SHORT TERM...BARNES
LONG TERM...AUTEN
AVIATION...BARNES
AREA FORECAST DISCUSSION
NWS NORTHERN INDIANA
228 PM EDT MON AUG 25 2014
.SYNOPSIS...
ISSUED AT 1056 AM EDT MON AUG 25 2014
HOT AND MUGGY CONDITIONS ACROSS THE REGION TODAY INTO TONIGHT.
DEWPOINTS IN THE LOWER 70S WILL CREATE MUGGY CONDITIONS AS HIGH
PRESSURE RETAINS ITS INFLUENCE OVER US. A FRONTAL SYSTEM TO THE
WEST COULD INTRODUCE SOME RAIN TO THE NORTHERN PORTION OF THE
REGION TONIGHT AS IT APPROACHES. HIGH TEMPERATURES TODAY WILL BE IN
THE UPPER 80S TO AROUND 90 WITH THE HEAT INDEX IN THE 90S TO NEAR 100.
LOW TEMPERATURES TONIGHT WILL RANGE FROM THE UPPER 60S NEAR THE
OHIO RIVER TO THE LOWER 70S IN SOUTHERN MICHIGAN.
&&
.UPDATE...
ISSUED AT 1242 PM EDT MON AUG 25 2014
FOCUS FOR THE REMAINDER OF THE AFTERNOON WILL CENTER ON CONVECTIVE
POTENTIAL AND HEAT. RESIDUAL OUTFLOW BOUNDARY FROM UPSTREAM
CONVECTION HAS ALLOWED FOR RENEWED THUNDERSTORM DEVELOPMENT ACROSS
NORTHEAST ILLINOIS. REMNANT OUTFLOW/CONVECTIVE VORT FROM UPSTREAM
CONVECTION WILL HAVE PLENTY OF DOWNSTREAM INSTABILITY TO WORK THIS
AFTERNOON WITH INDICATIONS IN RUC SHORT TERM PROGS OF 3-4K J/KG OF
100 HPA MLCAPES WORKING INTO WESTERN PORTIONS OF THE AREA. DEEP
LAYER SHEAR IS WEAK...BUT GIVEN MAGNITUDE OF INSTABILITY WILL HAVE
TO MONITOR FOR POSSIBILITY OF ISOLATED STRONG/SEVERE STORMS THIS
AFTERNOON. WITH EARLY AFTERNOON UPDATE...WILL GO AHEAD AND MAKE
SOME SOUTHEAST EXPANSION OF SLIGHT CHANCE AND PERHAPS RAISE POPS A
BIT IN THE FAR NORTHWEST DUE TO APPROACH OF OUTFLOW BOUNDARY.
TEMPERATURES/DEW POINTS APPEAR TO BE IN GOOD SHAPE WITH PEAK
AFTERNOON HEAT INDICES STILL LIKELY TO REACH INTO THE UPPER 90S
ACROSS THE WEST. WILL CONTINUE TO GO WITH CURRENT SPS FOR THIS
AFTERNOON TO HIGHLIGHT HAZARDOUS CONDITIONS ASSOCIATED WITH THE
HEAT/HUMIDITY.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 404 AM EDT MON AUG 25 2014
FOCUS OF PERIOD WILL BE TWO FOLD...TEMPERATURES/HEAT INDEX ISSUES AND
CHANCES FOR STORMS.
WARM AND MUGGY CONDITIONS WERE IN PLACE ACROSS THE AREA WITH
TEMPERATURES IN THE 70S AND DEWPOINTS IN THE UPPER 60S NE TO LOWER
70S SW WITH MOST UNSTABLE CAPE VALUES IN THE 500 TO 1500 J/KG RANGE.
WITH NO REAL TRIGGER ACROSS THE AREA NO SHOWERS/STORMS HAVE FORMED
THUS FAR. MAIN FOCUS FOR STORMS HAS BEEN FROM NORTHERN WISCONSIN
INTO PORTIONS OF CENTRAL IOWA WHERE 30 TO 35 KT LOW LEVEL JET WAS
AIDING IN DEVELOPMENT AND MAINTENANCE OF A BROKEN LINE OF STRONG
TO LOCALLY SEVERE STORMS. HI RES MODELS ALL SUGGEST THIS LINE WILL
DROP SLOWLY SOUTHEAST BUT VARY IN HOW MUCH HOLD TOGETHER AS WE
APPROACH 12Z MON AND POINTS BEYOND. WOULD SEEM REASONABLE THAT
SOME SORT OF OUTFLOW BOUNDARY OR REMNANT SHOWERS/STORMS COULD
APPROACH NW AREAS THIS AFTERNOON AND THEN STALL SOMEWHERE TONIGHT
BEING REINFORCED SOMEWHAT BY SFC FRONT THAT WILL BE SINKING SOUTH.
ONLY CHANGE TO GRIDS WILL BE REORIENTATION OF SLGT CHC POPS TO
MORE OF A SW TO NE ORIENTATION. IF SUFFICIENT HEATING TAKES PLACE
AND PROGGED INSTABILITY IS AVAILABLE (SURFACE BASED CAPES IN
EXCESS OF 4000 J/KG IN A WEAKLY SHEAR ENVIRONMENT) THEN SOME
STRONGER STORMS COULD BE A CONCERN.
NOW FOR TEMPERATURES...THE WARM START TO THE MORNING SHOULD ALLOW
TEMPERATURES TO QUICKLY CLIMB INTO THE 80S BY NOON TIME AND POSSIBLY
CLOSE TO 90 IN WESTERN AREAS. DEWPOINTS IN WESTERN AREAS LOOK TO
CLIMB INTO THE MIDDLE 70S IN SOME SPOTS WHICH IF TEMPS DO APPROACH
90 WILL EDGE REAL CLOSE TO HEAT ADVISORY LEVELS (EVEN BRIEFLY TOUCH
IN FAR WEST). WILL HANDLE WITH HWO AND SPS FOR NOW AND LET DAY SHIFT
ASSESS THINGS AFTER SUNRISE AS TO EXTENT OF CLOUD COVER AND POSSIBLE
INFLUENCE FROM UPSTREAM CONVECTION. LOWS TONIGHT WILL DROP BACK INTO
THE UPR 60S TO LOWER 70S.
&&
.LONG TERM...(TUESDAY THROUGH SUNDAY)
ISSUED AT 404 AM EDT MON AUG 25 2014
LOW OVER SRN MANITOBA THIS MORNING EXPECTED TO LIFT NE INTO QUEBEC
TUESDAY WITH TRAILING CDFNT MOVG INTO OUR CWA. WK FORCING ALONG THE
FRONT COMBINED WITH SOME CAPPING ASSOCIATED WITH UPR RIDGE OVER THE
OH/MID MS VALLEY LIMITS TSTM POTENTIAL TO CHC DESPITE AT LEAST
MODERATE INSTABILITY IN PLACE OVER THE AREA. TEMPS WILL REMAIN ABOVE
NORMAL WITH HIGHS IN THE UPPER 80S AND PM HEAT INDEX READINGS IN THE
90S.
CDFNT EXPECTED TO SAG SOUTH INTO CENTRAL OH/IN TUE NGT. POTENTIAL
FOR TSTMS INCREASES A BIT IN THIS TIMEFRAME AS A SHRTWV CURRENTLY
OVER WRN CANADA MOVES TO THE UPR GRTLKS RESULTING IN MINOR HEIGHT
FALLS AS FAR SOUTH AS OUR CWA. WK CAA SHOULD ALLOW FOR LOWS TO FALL
INTO THE M-U60S ACROSS THE AREA.
RAIN CHANCES DIMINISH WED-WED NGT AS FRONT CONTS TO SAG SOUTH TO THE
OH VALLEY AND SFC HIGH MOVES ESE INTO THE UPR GRTLKS. TEMPS SHOULD
FALL BACK CLOSER TO NORMAL WITH HIGHS IN THE L80S AND LOWS IN THE
L-M60S.
FRONTAL SYSTEM EXPECTED TO LIFT BACK NORTH INTO OUR AREA THU-THU NGT
AS SFC HIGH MOVES TO THE MID ATLANTIC/NORTHEAST U.S.. DVLPG SPLIT
FLOW CUT-OFF LOW OVER THE WRN U.S. BY MID WEEK IS EXPECTED TO MOVE
SLOWLY EAST TO THE CENTRAL PLAINS FRIDAY AND INTO THE MID MS VALLEY
BY SUNDAY WHILE SFC BOUNDARY LINGERS OVER THE AREA... ENHANCING TSTM
POTENTIAL ACROSS OUR AREA OVER THE LABOR DAY WEEKEND... WHILE TEMPS
REMAIN CLOSE TO NORMAL.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON)
ISSUED AT 200 PM EDT MON AUG 25 2014
AN OUTFLOW BOUNDARY ASSOCIATED WITH OVERNIGHT UPSTREAM CONVECTION
HAS BEEN A TRIGGER MECHANISM FOR SHOWERS AND THUNDERSTORMS ACROSS
NORTHEAST ILLINOIS AND SOUTHERN LOWER MICHIGAN. THIS BOUNDARY
SHOULD CONTINUE TO DROP INTO NORTH CENTRAL INDIANA BY 20Z. A
STRONGLY UNSTABLE ENVIRONMENT EXISTS ACROSS THE AREA...WITH MAIN
NEGATIVE FACTOR TO SOUTHEAST EXPANSION OF THE SHOWERS AND STORMS
IS BACKGROUND WEAK UPPER FORCING AND PRESENCE OF MID/UPPER LEVEL
RIDGING. HAVE CARRIED A VCTS MENTION AT KSBN FROM 20Z-22Z AND WILL
BE MONITORING TRENDS OVER NEXT HOUR OR SO FOR POSSIBLE TSRA
INCLUSION. SOUTH WINDS AT KSBN MAY BECOME NORTHWEST FOR A TIME IN
THE 20Z-22Z TIMEFRAME DUE TO THE PASSAGE OF THE OUTFLOW
BOUNDARY...OR VARIABLE IN NATURE. A SHEARED UPPER VORT MAX FROM
CENTRAL WISCONSIN INTO EASTERN IOWA WILL TRACK INTO NORTHWEST
INDIANA THIS EVENING WITH SOME POSSIBILITY OF ADDITIONAL ISOLATED
THUNDERSTORMS. OTHER THAN PASSAGE OF THIS WEAK WAVE THIS
EVENING...FORCING WILL BE SOMEWHAT WEAK WITH LOW CONFIDENCE IN
TIMING AND WILL KEEP TAFS DRY THROUGH THE END OF THE PERIOD.
CHANCES OF THUNDER MAY INCREASE LATE TONIGHT INTO TUESDAY MORNING
AS LOW LEVEL FRONT BEGINS TO APPROACH THE AREA...BUT CONFIDENCE
REMAINS LOW IN TIMING/COVERAGE.
&&
.IWX WATCHES/WARNINGS/ADVISORIES...
IN...NONE.
MI...NONE.
OH...NONE.
LM...NONE.
&&
$$
UPDATE...MARSILI
SYNOPSIS...LOTHAMER
SHORT TERM...FISHER
LONG TERM...JT
AVIATION...MARSILI
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
1259 PM EDT MON AUG 25 2014
.SYNOPSIS...
ISSUED AT 1056 AM EDT MON AUG 25 2014
HOT AND MUGGY CONDITIONS ACROSS THE REGION TODAY INTO TONIGHT.
DEWPOINTS IN THE LOWER 70S WILL CREATE MUGGY CONDITIONS AS HIGH
PRESSURE RETAINS ITS INFLUENCE OVER US. A FRONTAL SYSTEM TO THE
WEST COULD INTRODUCE SOME RAIN TO THE NORTHERN PORTION OF THE
REGION TONIGHT AS IT APPROACHES. HIGH TEMPERATURES TODAY WILL BE IN
THE UPPER 80S TO AROUND 90 WITH THE HEAT INDEX IN THE 90S TO NEAR 100.
LOW TEMPERATURES TONIGHT WILL RANGE FROM THE UPPER 60S NEAR THE
OHIO RIVER TO THE LOWER 70S IN SOUTHERN MICHIGAN.
&&
.UPDATE...
ISSUED AT 1242 PM EDT MON AUG 25 2014
FOCUS FOR THE REMAINDER OF THE AFTERNOON WILL CENTER ON CONVECTIVE
POTENTIAL AND HEAT. RESIDUAL OUTFLOW BOUNDARY FROM UPSTREAM
CONVECTION HAS ALLOWED FOR RENEWED THUNDERSTORM DEVELOPMENT ACROSS
NORTHEAST ILLINOIS. REMNANT OUTFLOW/CONVECTIVE VORT FROM UPSTREAM
CONVECTION WILL HAVE PLENTY OF DOWNSTREAM INSTABILITY TO WORK THIS
AFTERNOON WITH INDICATIONS IN RUC SHORT TERM PROGS OF 3-4K J/KG OF
100 HPA MLCAPES WORKING INTO WESTERN PORTIONS OF THE AREA. DEEP
LAYER SHEAR IS WEAK...BUT GIVEN MAGNITUDE OF INSTABILITY WILL HAVE
TO MONITOR FOR POSSIBILITY OF ISOLATED STRONG/SEVERE STORMS THIS
AFTERNOON. WITH EARLY AFTERNOON UPDATE...WILL GO AHEAD AND MAKE
SOME SOUTHEAST EXPANSION OF SLIGHT CHANCE AND PERHAPS RAISE POPS A
BIT IN THE FAR NORTHWEST DUE TO APPROACH OF OUTFLOW BOUNDARY.
TEMPERATURES/DEW POINTS APPEAR TO BE IN GOOD SHAPE WITH PEAK
AFTERNOON HEAT INDICES STILL LIKELY TO REACH INTO THE UPPER 90S
ACROSS THE WEST. WILL CONTINUE TO GO WTIH CURRENT SPS FOR THIS
AFTERNOON TO HIGHLIGHT HAZARDOUS CONDITIONS ASSOCIATED WITH THE
HEAT/HUMIDITY.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 404 AM EDT MON AUG 25 2014
FOCUS OF PERIOD WILL BE TWO FOLD...TEMPERATURES/HEAT INDEX ISSUES AND
CHANCES FOR STORMS.
WARM AND MUGGY CONDITIONS WERE IN PLACE ACROSS THE AREA WITH
TEMPERATURES IN THE 70S AND DEWPOINTS IN THE UPPER 60S NE TO LOWER
70S SW WITH MOST UNSTABLE CAPE VALUES IN THE 500 TO 1500 J/KG RANGE.
WITH NO REAL TRIGGER ACROSS THE AREA NO SHOWERS/STORMS HAVE FORMED
THUS FAR. MAIN FOCUS FOR STORMS HAS BEEN FROM NORTHERN WISCONSIN
INTO PORTIONS OF CENTRAL IOWA WHERE 30 TO 35 KT LOW LEVEL JET WAS
AIDING IN DEVELOPMENT AND MAINTENANCE OF A BROKEN LINE OF STRONG
TO LOCALLY SEVERE STORMS. HI RES MODELS ALL SUGGEST THIS LINE WILL
DROP SLOWLY SOUTHEAST BUT VARY IN HOW MUCH HOLD TOGETHER AS WE
APPROACH 12Z MON AND POINTS BEYOND. WOULD SEEM REASONABLE THAT
SOME SORT OF OUTFLOW BOUNDARY OR REMNANT SHOWERS/STORMS COULD
APPROACH NW AREAS THIS AFTERNOON AND THEN STALL SOMEWHERE TONIGHT
BEING REINFORCED SOMEWHAT BY SFC FRONT THAT WILL BE SINKING SOUTH.
ONLY CHANGE TO GRIDS WILL BE REORIENTATION OF SLGT CHC POPS TO
MORE OF A SW TO NE ORIENTATION. IF SUFFICIENT HEATING TAKES PLACE
AND PROGGED INSTABILITY IS AVAILABLE (SURFACE BASED CAPES IN
EXCESS OF 4000 J/KG IN A WEAKLY SHEAR ENVIRONMENT) THEN SOME
STRONGER STORMS COULD BE A CONCERN.
NOW FOR TEMPERATURES...THE WARM START TO THE MORNING SHOULD ALLOW
TEMPERATURES TO QUICKLY CLIMB INTO THE 80S BY NOON TIME AND POSSIBLY
CLOSE TO 90 IN WESTERN AREAS. DEWPOINTS IN WESTERN AREAS LOOK TO
CLIMB INTO THE MIDDLE 70S IN SOME SPOTS WHICH IF TEMPS DO APPROACH
90 WILL EDGE REAL CLOSE TO HEAT ADVISORY LEVELS (EVEN BRIEFLY TOUCH
IN FAR WEST). WILL HANDLE WITH HWO AND SPS FOR NOW AND LET DAY SHIFT
ASSESS THINGS AFTER SUNRISE AS TO EXTENT OF CLOUD COVER AND POSSIBLE
INFLUENCE FROM UPSTREAM CONVECTION. LOWS TONIGHT WILL DROP BACK INTO
THE UPR 60S TO LOWER 70S.
&&
.LONG TERM...(TUESDAY THROUGH SUNDAY)
ISSUED AT 404 AM EDT MON AUG 25 2014
LOW OVER SRN MANITOBA THIS MORNING EXPECTED TO LIFT NE INTO QUEBEC
TUESDAY WITH TRAILING CDFNT MOVG INTO OUR CWA. WK FORCING ALONG THE
FRONT COMBINED WITH SOME CAPPING ASSOCIATED WITH UPR RIDGE OVER THE
OH/MID MS VALLEY LIMITS TSTM POTENTIAL TO CHC DESPITE AT LEAST
MODERATE INSTABILITY IN PLACE OVER THE AREA. TEMPS WILL REMAIN ABOVE
NORMAL WITH HIGHS IN THE UPPER 80S AND PM HEAT INDEX READINGS IN THE
90S.
CDFNT EXPECTED TO SAG SOUTH INTO CENTRAL OH/IN TUE NGT. POTENTIAL
FOR TSTMS INCREASES A BIT IN THIS TIMEFRAME AS A SHRTWV CURRENTLY
OVER WRN CANADA MOVES TO THE UPR GRTLKS RESULTING IN MINOR HEIGHT
FALLS AS FAR SOUTH AS OUR CWA. WK CAA SHOULD ALLOW FOR LOWS TO FALL
INTO THE M-U60S ACROSS THE AREA.
RAIN CHANCES DIMINISH WED-WED NGT AS FRONT CONTS TO SAG SOUTH TO THE
OH VALLEY AND SFC HIGH MOVES ESE INTO THE UPR GRTLKS. TEMPS SHOULD
FALL BACK CLOSER TO NORMAL WITH HIGHS IN THE L80S AND LOWS IN THE
L-M60S.
FRONTAL SYSTEM EXPECTED TO LIFT BACK NORTH INTO OUR AREA THU-THU NGT
AS SFC HIGH MOVES TO THE MID ATLANTIC/NORTHEAST U.S.. DVLPG SPLIT
FLOW CUT-OFF LOW OVER THE WRN U.S. BY MID WEEK IS EXPECTED TO MOVE
SLOWLY EAST TO THE CENTRAL PLAINS FRIDAY AND INTO THE MID MS VALLEY
BY SUNDAY WHILE SFC BOUNDARY LINGERS OVER THE AREA... ENHANCING TSTM
POTENTIAL ACROSS OUR AREA OVER THE LABOR DAY WEEKEND... WHILE TEMPS
REMAIN CLOSE TO NORMAL.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z TUESDAY MORNING)
ISSUED AT 655 AM EDT MON AUG 25 2014
STRATUS/FOG WITH MVFR/IFR CONDITIONS ATTM SHOULD MIX OUT/BURN OFF
TO VFR BY MID-MORNING. BKN LINE OF TSRA OVER IA/WI MOVG EAST
20KTS. CONVECTIVE ALLOWING MODELS IN DECENT AGREEMENT THAT THIS
CONVECTION WILL GRDLY DIMINISH AS IT MOVES EAST THIS MORNING WHICH
SEEMS REASONABLE AS IT MOVES INTO MORE CAPPED AIRMASS OVER OUR
AREA. COULD BE SCT REMNANT -SHRA/VFR CIGS BRIEF WIND GUSTS AS
REMNANTS MOVE THROUGH SBN TOWARD MIDDAY TOO MUCH UNCERTAINTY
REMAINS TO ADD ANYTHING SGFNT TO TAFS. OUTFLOW BOUNDARY FROM THIS
DYING CONVECTION COULD SET UP OVER NRN INDIANA AND SUPPORT
ISOLATED CONVECTIVE INITIATION AROUND PEAK HEATING BUT CHANCES OF
ANYTHING IMPACTING TERMINALS TOO LOW TO MENTION IN TAFS. APCHG
CDFNT MAY SPREAD SOME SHRA/TSRA INTO NRN INDIANA LATE TONIGHT. FOR
NOW JUST MENTIONED VCSH CLOSEST TO APCHG CDFNT AT SBN... BUT DID
ADD MVFR BR TO BOTH TAFS LATE AS BOUNDARY LAYER REMAINS VERY
MOIST.
&&
.IWX WATCHES/WARNINGS/ADVISORIES...
IN...NONE.
MI...NONE.
OH...NONE.
LM...NONE.
&&
$$
UPDATE...MARSILI
SYNOPSIS...LOTHAMER
SHORT TERM...FISHER
LONG TERM...JT
AVIATION...JT
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 QUAD CITIES IA IL
131 PM CDT MON AUG 25 2014
.UPDATE...
ISSUED AT 126 PM CDT MON AUG 25 2014
ISOLATED SEVERE STORMS EXPECTED THIS AFTN PORTIONS OF NORTHEAST AND
EAST CENTRAL IA INTO NORTHWEST IL WITHIN STRONG THERMAL AND
INSTABILITY GRADIENT AHEAD OF WEAK SURFACE LOW MOVING INTO EASTERN
IA. MAIN THREAT WILL BE DAMAGING DOWNBURST WINDS AROUND 60 MPH.
LOCALLY HEAVY RAINFALL ALSO EXPECTED WITH THE STORMS. HAVE UPDATED
THE HWO. IN PROCESS OF SENDING UP A 19Z BALLOON TO BETTER SAMPLE
THE ENVIRONMENT. WILL BE SENDING GRID/ZFP/PFM UPDATE SHORTLY. THIS
WILL ENCORPORATE CONVECTIVE TRENDS AND ALSO LOWERING OF HIGHS
WITH LINGERING COOL POOL OVER PORTIONS OF NORTHEAST IA INTO NORTHWEST
IL.
&&
.SYNOPSIS...
ISSUED AT 334 AM CDT MON AUG 25 2014
THUNDERSTORMS HAVE DEVELOPED EARLY THIS MORNING ALONG AND AHEAD OF
THE SURFACE FRONT EXTENDING ROUGHLY FROM WESTERN LAKE SUPERIOR SW
ACROSS WESTERN WI...SW MN...INTO W CENTRAL IA. THIS WAS ALONG AN
AXIS OF HIGH THETAE INDICATED BY 850 MB DEWPOINTS OF 14 TO 16 C FROM
NORTHEAST KS INTO SW ONTARIO AT 00Z...WITH CONVERGENCE ASSISTED
BY 35KT TO 40 KT SW WINDS AT 850 MB. THIS MOISTURE WAS BEING
PULLED NORTHWARD BY A STRONG SURFACE AND UPPER LEVEL LOW SEEN ON
WV IMAGERY ALONG THE ND/MANITOBA BORDER. AT 3 AM...THE LEADING
LINE OF SCATTERED THUNDERSTORMS WAS MOVING INTO BUCHANAN AND
BENTON COUNTIES...INTO A VERY HUMID AIRMASS WITH DEWPOINTS IN THE
LOWER TO MID 70S AND AIR TEMPERATURES IN THE MID TO UPPER 70S.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 334 AM CDT MON AUG 25 2014
FORECAST CHALLENGES CENTER ON THUNDERSTORMS THIS MORNING AND AGAIN
TONIGHT...AND HEAT HEADLINES TODAY AS THE HOT AND HUMID CONDITIONS
PERSIST OVER THE REGION. IN THE NEAR TERM...A SEMI-LINEAR MCS WILL
LIKELY MOVE ACROSS THE FORECAST AREA MAINLY NORTH OF I-80...DRIVEN
BY A WEAK SHORTWAVE FLOW IN THE NW FLOW ALOFT. WHILE NO INDIVIDUAL
FORECAST MODEL HAS HAD A GOOD HANDLE ON TRENDS OVERNIGHT...THE
HIGH RES WRF AND RAP MODELS APPEAR TO HAVE THE BEST HANDLE ON THE
CONVECTION ENTERING THE NORTH. THESE HAVE THE THUNDERSTORMS ADVANCING
THROUGH THE NORTH OVER THE NEXT SEVERAL HOURS AND THEN DISSIPATING
BY NOON...AND HAVE TRENDED THE FORECAST ACCORDINGLY. THE LATEST
RAP IS ALONE WITH DEVELOPING THUNDERSTORMS IN THE HIGH MUCAPE
AXIS FURTHER SE...OVER 4000 J/KG...OVER W CENTRAL IL TOWARD
SUNRISE...WHICH WHILE NOT IN THE CURRENT FORECAST CANNOT BE
ENTIRELY RULED AND WILL WATCH TRENDS CLOSELY.
OTHERWISE...THIS SHOULD BE FOLLOWED BY CLEARING SKIES AND A RETURN
TO THE HEAT AND HUMIDITY SEEN OVER THE AREA YESTERDAY. DUE TO
UNCERTAINTIES IN THE TIMING OF THE DISSIPATING MCS IN THE NORTH AND
POSSIBLE DEBRIS CLOUDS FROM STORMS IN THE PLAINS...ALONG WITH 850 MB
TEMPERATURES PROGGED ABOUT 1 DEGREE COOLER...HAVE TRENDED HIGHS A
DEGREE OR TWO COOLER THAN SUNDAY...WITH UPPER 80S NW TO LOWER 90S
CENTRAL AND SOUTH. DEWPOINTS WILL HOLD IN THE LOWER TO MID 70S AND
POSSIBLY TOUCH THE UPPER 70S AT TIMES LATE IN THE DAY. THIS
COMBINATION WILL SEND HEAT INDEX VALUES TO JUST ABOVE 100 ACROSS
THE SOUTH AND WILL KEEP THE PREVIOUS HEAT ADVISORY CONFIGURATION
IN PLACE.
TONIGHT...THE SETUP WILL BE FAVORABLE FOR ANOTHER MCS AS THE SURFACE
FRONT SLOWLY ADVANCES THROUGH THE FORECAST AREA AND MODEST
CONVERGENCE OCCURS IN THE 850 MB THETAE AXIS AS IT SHIFTS OVERHEAD.
HAVE KEPT LIKELY POPS IN THE NORTH WITH SLIGHT TO LOW END CHANCE
POPS IN THE SOUTH TOWARD MORNING. THE MAIN THREAT WILL BE LOCALLY
HEAVY RAINFALL. IT WILL BE ANOTHER WARM AND VERY HUMID NIGHT WITH
TEMPERATURES AND DEWPOINTS IN THE 70S...EXCEPT IN THE FAR NW...WHERE
THE CURRENT FRONTAL TIMING SUGGESTS READINGS LOWERING INTO THE
UPPER 60S.
.LONG TERM...(TUESDAY THROUGH SUNDAY)
ISSUED AT 334 AM CDT MON AUG 25 2014
AN ORGANIZED THUNDERSTORM COMPLEX SHOULD MOVE INTO THE AREA TUESDAY
MORNING AND DISSIPATE DURING THE MORNING. BOUNDARIES LEFT OVER FROM
THIS COMPLEX COMBINED WITH A WEAK FRONT MOVING THROUGH THE AREA WILL
PROVIDE THE FOCUS FOR NEW CONVECTION TUESDAY AFTERNOON AND EVENING.
HIGH MOISTURE LEVELS IN THE LOWER ATMOSPHERE MEANS ANY STORM WILL BE
CAPABLE OF PRODUCING LOCALLY HEAVY RAINFALL.
CLOUD COVER AND RAIN WILL PLAY INTO HOW WARM IT WILL GET ON TUESDAY.
THE SOUTHEAST HALF MAY SEE TEMPERATURES AROUND 90 WITH HEAT INDEX
READINGS IN THE UPPER 90S TO JUST OVER 100.
ANOTHER THUNDERSTORM COMPLEX IS EXPECTED TO DEVELOP IN WESTERN IOWA
TUESDAY EVENING AND THEN MOVE MAINLY EAST OVERNIGHT INTO WEDNESDAY
MORNING. THIS STORM COMPLEX SHOULD ARRIVE IN THE WESTERN THIRD OF
THE CWFA IN THE PRE-DAWN HOURS AND SLOWLY DISSIPATE ACROSS THE AREA
WEDNESDAY MORNING. LOCALLY HEAVY RAINFALL WILL BE POSSIBLE FROM THE
STORMS DUE TO HIGH MOISTURE LEVELS.
LIKE TUESDAY...BOUNDARIES LEFT OVER FROM THE WEDNESDAY STORM COMPLEX
WILL PROVIDE THE FOCUS FOR NEW CONVECTION WEDNESDAY AFTERNOON AND
EVENING.
SIGNALS FROM THE MODELS SUGGEST YET ANOTHER THUNDERSTORM COMPLEX
WILL DEVELOP IN WESTERN IOWA WEDNESDAY EVENING AND MOVE GENERALLY
EAST OVERNIGHT AND ARRIVE IN THE WESTERN THIRD OF THE AREA IN THE
PRE-DAWN HOURS. LOCALLY HEAVY RAINFALL MAY BE POSSIBLE FROM SOME OF
THE STRONGER STORMS.
THURSDAY ON...
THE MODEL CONSENSUS HAS CHANCE POPS IN EACH 12 HOUR PERIOD FROM
THURSDAY THROUGH SATURDAY NIGHT. TEMPERATURES SHOULD BE NEAR NORMAL.
ON SUNDAY...THE MODEL CONSENSUS HAS SLIGHT CHANCE TO LOW CHANCE POPS.
THE LARGE SCALE PICTURE SUGGESTS THE WEATHER PATTERN WILL REMAIN
FAIRLY ACTIVE WITH A FRONT STALLED OUT JUST SOUTH OF THE AREA. IT
WILL NOT RAIN CONTINUOUSLY THE ENTIRE TIME. THERE WILL BE PERIODS OF
DRY WEATHER THAT MAY LAST 6 OR 12 HOURS.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON)
ISSUED AT 100 PM CDT MON AUG 25 2014
LINE OF SHOWERS AND STORMS EXTENDS JUST SOUTH AND EAST OF DBQ TO
CID TERMINAL MOVING EAST. ADDITIONAL DEVELOPMENT EXPECTED NEAR
AND NORTH OF I-80 THIS AFTERNOON WITH VARIOUS OUTFLOW BOUNDARIES.
FRONT OVER CENTRAL IA TO PROGRESS EAST AND PASS THROUGH THE
TERMINALS TONIGHT BRINGING SHIFT IN WINDS TO NORTHERLY. ANTICIPATE
SHOWERS AND STORMS TO DEVELOP NORTH OF THE FRONT TONIGHT INTO
TUESDAY MORNING WITH THE GREATEST CHANCES RIGHT NOW LOOKING
NEAR AND NORTH OF I-80. CONDITIONS IN ANY CONVECTION WILL BE
MVFR TO IFR. GUSTY WINDS OF 30+ KTS WILL ALSO BE POSSIBLE WITH
THE STRONGER STORMS THIS AFTERNOON.
&&
.DVN WATCHES/WARNINGS/ADVISORIES...
IA...HEAT ADVISORY UNTIL 8 PM CDT THIS EVENING FOR DES MOINES-HENRY
IA-LEE-LOUISA-MUSCATINE-SCOTT-VAN BUREN.
IL...HEAT ADVISORY UNTIL 8 PM CDT THIS EVENING FOR BUREAU-HANCOCK-
HENDERSON-HENRY IL-MCDONOUGH-MERCER-PUTNAM-ROCK ISLAND-
WARREN-WHITESIDE.
MO...HEAT ADVISORY UNTIL 8 PM CDT THIS EVENING FOR CLARK-SCOTLAND.
&&
$$
UPDATE...05
SYNOPSIS...SHEETS
SHORT TERM...SHEETS
LONG TERM...08
AVIATION...05
AREA FORECAST DISCUSSION
NWS QUAD CITIES IA IL
108 PM CDT MON AUG 25 2014
.UPDATE...
ISSUED AT 1121 AM CDT MON AUG 25 2014
HAVE UPDATED TO BUMP UP POPS AND EXTEND THROUGH THE AFTERNOON AS
LOOKING LIKELY TO SEE AT LEAST SCATTERED ACTIVITY PERSIST ALL
DAY MOSTLY NORTH OF I-80 WITH MORE ISOLATED OVER SOUTHEAST IA.
THIS ACTIVITY WILL BE AIDED BY WEAK SURFACE LOW NORTHEAST OF
DES MOINES AND INTERACTING WITH OUTFLOW BOUNDARIES...WITH MAIN
BOUNDARY OF NOTE ARCING JUST SOUTH OF I-80. WITH LINGERING
CONVECTION AND DEBRIS CLOUDS HAVE TWEAKED HIGHS DOWN OVER PORTIONS
OF NORTHEAST IA AND FAR NORTHWEST IL INTO THE MID 80S... BUT
WITH DUBUQUE STILL AT 71 DEGS AT 11 AM WOULD NOT BE SURPRISED TO
SEE SOME AREAS STRUGGLE TO HIT 80 OR LOWER 80S FAR NORTH. OTHERWISE
CURRENT HEAT ADVISORY HEADLINE ON TRACK FROM AROUND QUAD CITIES
SOUTH/EAST WITH FEW LOCATIONS ALREADY AT 90 DEGS AND HEAT INDEX
READINGS APPROACHING 100.
LOOKING FURTHER AHEAD TO TONIGHT AND TUESDAY... COLD FRONT THROUGH
NORTHWEST IA MOVING A BIT FASTER THAN MODELS AND LIKELY TO BE
LOCATED SOUTH OF THE CWA TUESDAY MORNING. ANTICIPATE POTENTIAL FOR
MORE ORGANIZED CONVECTION MOVING ACROSS NORTH 1/3-1/2 LATER
TONIGHT INTO TUE AM. IF TRENDS PERSIST THEN GOING FORECAST HIGHS
TOMORROW ARE LIKELY TOO WARM...POSSIBLY BY AS MUCH AS 5-10 DEGS
NOTING THAT AS WE ARE APPROACHING THE NOON HOUR TEMPS ARE IN THE
UPPER 60S TO LOWER 70S IN NORTHWEST IA POST FRONTAL WITH SUNSHINE.
THUS WITH CLOUDS AND RAIN COULD EASILY SEE AREAS STUCK IN THE 70S
ALL DAY TOMORROW. HAVE NOT MADE CHANGES YET AS STILL EVALUATING
MODEL SUITE... AND WILL HAVE MORE ON THIS WITH AFTERNOON DISCO.
UPDATED GRIDS/ZFP/PFM HAVE BEEN ISSUED.
&&
.SYNOPSIS...
ISSUED AT 334 AM CDT MON AUG 25 2014
THUNDERSTORMS HAVE DEVELOPED EARLY THIS MORNING ALONG AND AHEAD OF
THE SURFACE FRONT EXTENDING ROUGHLY FROM WESTERN LAKE SUPERIOR SW
ACROSS WESTERN WI...SW MN...INTO W CENTRAL IA. THIS WAS ALONG AN
AXIS OF HIGH THETAE INDICATED BY 850 MB DEWPOINTS OF 14 TO 16 C FROM
NORTHEAST KS INTO SW ONTARIO AT 00Z...WITH CONVERGENCE ASSISTED
BY 35KT TO 40 KT SW WINDS AT 850 MB. THIS MOISTURE WAS BEING
PULLED NORTHWARD BY A STRONG SURFACE AND UPPER LEVEL LOW SEEN ON
WV IMAGERY ALONG THE ND/MANITOBA BORDER. AT 3 AM...THE LEADING
LINE OF SCATTERED THUNDERSTORMS WAS MOVING INTO BUCHANAN AND
BENTON COUNTIES...INTO A VERY HUMID AIRMASS WITH DEWPOINTS IN THE
LOWER TO MID 70S AND AIR TEMPERATURES IN THE MID TO UPPER 70S.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 334 AM CDT MON AUG 25 2014
FORECAST CHALLENGES CENTER ON THUNDERSTORMS THIS MORNING AND AGAIN
TONIGHT...AND HEAT HEADLINES TODAY AS THE HOT AND HUMID CONDITIONS
PERSIST OVER THE REGION. IN THE NEAR TERM...A SEMI-LINEAR MCS WILL
LIKELY MOVE ACROSS THE FORECAST AREA MAINLY NORTH OF I-80...DRIVEN
BY A WEAK SHORTWAVE FLOW IN THE NW FLOW ALOFT. WHILE NO INDIVIDUAL
FORECAST MODEL HAS HAD A GOOD HANDLE ON TRENDS OVERNIGHT...THE
HIGH RES WRF AND RAP MODELS APPEAR TO HAVE THE BEST HANDLE ON THE
CONVECTION ENTERING THE NORTH. THESE HAVE THE THUNDERSTORMS ADVANCING
THROUGH THE NORTH OVER THE NEXT SEVERAL HOURS AND THEN DISSIPATING
BY NOON...AND HAVE TRENDED THE FORECAST ACCORDINGLY. THE LATEST
RAP IS ALONE WITH DEVELOPING THUNDERSTORMS IN THE HIGH MUCAPE
AXIS FURTHER SE...OVER 4000 J/KG...OVER W CENTRAL IL TOWARD
SUNRISE...WHICH WHILE NOT IN THE CURRENT FORECAST CANNOT BE
ENTIRELY RULED AND WILL WATCH TRENDS CLOSELY.
OTHERWISE...THIS SHOULD BE FOLLOWED BY CLEARING SKIES AND A RETURN
TO THE HEAT AND HUMIDITY SEEN OVER THE AREA YESTERDAY. DUE TO
UNCERTAINTIES IN THE TIMING OF THE DISSIPATING MCS IN THE NORTH AND
POSSIBLE DEBRIS CLOUDS FROM STORMS IN THE PLAINS...ALONG WITH 850 MB
TEMPERATURES PROGGED ABOUT 1 DEGREE COOLER...HAVE TRENDED HIGHS A
DEGREE OR TWO COOLER THAN SUNDAY...WITH UPPER 80S NW TO LOWER 90S
CENTRAL AND SOUTH. DEWPOINTS WILL HOLD IN THE LOWER TO MID 70S AND
POSSIBLY TOUCH THE UPPER 70S AT TIMES LATE IN THE DAY. THIS
COMBINATION WILL SEND HEAT INDEX VALUES TO JUST ABOVE 100 ACROSS
THE SOUTH AND WILL KEEP THE PREVIOUS HEAT ADVISORY CONFIGURATION
IN PLACE.
TONIGHT...THE SETUP WILL BE FAVORABLE FOR ANOTHER MCS AS THE SURFACE
FRONT SLOWLY ADVANCES THROUGH THE FORECAST AREA AND MODEST
CONVERGENCE OCCURS IN THE 850 MB THETAE AXIS AS IT SHIFTS OVERHEAD.
HAVE KEPT LIKELY POPS IN THE NORTH WITH SLIGHT TO LOW END CHANCE
POPS IN THE SOUTH TOWARD MORNING. THE MAIN THREAT WILL BE LOCALLY
HEAVY RAINFALL. IT WILL BE ANOTHER WARM AND VERY HUMID NIGHT WITH
TEMPERATURES AND DEWPOINTS IN THE 70S...EXCEPT IN THE FAR NW...WHERE
THE CURRENT FRONTAL TIMING SUGGESTS READINGS LOWERING INTO THE
UPPER 60S.
.LONG TERM...(TUESDAY THROUGH SUNDAY)
ISSUED AT 334 AM CDT MON AUG 25 2014
AN ORGANIZED THUNDERSTORM COMPLEX SHOULD MOVE INTO THE AREA TUESDAY
MORNING AND DISSIPATE DURING THE MORNING. BOUNDARIES LEFT OVER FROM
THIS COMPLEX COMBINED WITH A WEAK FRONT MOVING THROUGH THE AREA WILL
PROVIDE THE FOCUS FOR NEW CONVECTION TUESDAY AFTERNOON AND EVENING.
HIGH MOISTURE LEVELS IN THE LOWER ATMOSPHERE MEANS ANY STORM WILL BE
CAPABLE OF PRODUCING LOCALLY HEAVY RAINFALL.
CLOUD COVER AND RAIN WILL PLAY INTO HOW WARM IT WILL GET ON TUESDAY.
THE SOUTHEAST HALF MAY SEE TEMPERATURES AROUND 90 WITH HEAT INDEX
READINGS IN THE UPPER 90S TO JUST OVER 100.
ANOTHER THUNDERSTORM COMPLEX IS EXPECTED TO DEVELOP IN WESTERN IOWA
TUESDAY EVENING AND THEN MOVE MAINLY EAST OVERNIGHT INTO WEDNESDAY
MORNING. THIS STORM COMPLEX SHOULD ARRIVE IN THE WESTERN THIRD OF
THE CWFA IN THE PRE-DAWN HOURS AND SLOWLY DISSIPATE ACROSS THE AREA
WEDNESDAY MORNING. LOCALLY HEAVY RAINFALL WILL BE POSSIBLE FROM THE
STORMS DUE TO HIGH MOISTURE LEVELS.
LIKE TUESDAY...BOUNDARIES LEFT OVER FROM THE WEDNESDAY STORM COMPLEX
WILL PROVIDE THE FOCUS FOR NEW CONVECTION WEDNESDAY AFTERNOON AND
EVENING.
SIGNALS FROM THE MODELS SUGGEST YET ANOTHER THUNDERSTORM COMPLEX
WILL DEVELOP IN WESTERN IOWA WEDNESDAY EVENING AND MOVE GENERALLY
EAST OVERNIGHT AND ARRIVE IN THE WESTERN THIRD OF THE AREA IN THE
PRE-DAWN HOURS. LOCALLY HEAVY RAINFALL MAY BE POSSIBLE FROM SOME OF
THE STRONGER STORMS.
THURSDAY ON...
THE MODEL CONSENSUS HAS CHANCE POPS IN EACH 12 HOUR PERIOD FROM
THURSDAY THROUGH SATURDAY NIGHT. TEMPERATURES SHOULD BE NEAR NORMAL.
ON SUNDAY...THE MODEL CONSENSUS HAS SLIGHT CHANCE TO LOW CHANCE POPS.
THE LARGE SCALE PICTURE SUGGESTS THE WEATHER PATTERN WILL REMAIN
FAIRLY ACTIVE WITH A FRONT STALLED OUT JUST SOUTH OF THE AREA. IT
WILL NOT RAIN CONTINUOUSLY THE ENTIRE TIME. THERE WILL BE PERIODS OF
DRY WEATHER THAT MAY LAST 6 OR 12 HOURS.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON)
ISSUED AT 100 PM CDT MON AUG 25 2014
LINE OF SHOWERS AND STORMS EXTENDS JUST SOUTH AND EAST OF DBQ TO
CID TERMINAL MOVING EAST. ADDITIONAL DEVELOPMENT EXPECTED NEAR
AND NORTH OF I-80 THIS AFTERNOON WITH VARIOUS OUTFLOW BOUNDARIES.
FRONT OVER CENTRAL IA TO PROGRESS EAST AND PASS THROUGH THE
TERMINALS TONIGHT BRINGING SHIFT IN WINDS TO NORTHERLY. ANTICIPATE
SHOWERS AND STORMS TO DEVELOP NORTH OF THE FRONT TONIGHT INTO
TUESDAY MORNING WITH THE GREATEST CHANCES RIGHT NOW LOOKING
NEAR AND NORTH OF I-80. CONDITIONS IN ANY CONVECTION WILL BE
MVFR TO IFR. GUSTY WINDS OF 30+ KTS WILL ALSO BE POSSIBLE WITH
THE STRONGER STORMS THIS AFTERNOON.
&&
.DVN WATCHES/WARNINGS/ADVISORIES...
IA...HEAT ADVISORY UNTIL 8 PM CDT THIS EVENING FOR DES MOINES-HENRY
IA-LEE-LOUISA-MUSCATINE-SCOTT-VAN BUREN.
IL...HEAT ADVISORY UNTIL 8 PM CDT THIS EVENING FOR BUREAU-HANCOCK-
HENDERSON-HENRY IL-MCDONOUGH-MERCER-PUTNAM-ROCK ISLAND-
WARREN-WHITESIDE.
MO...HEAT ADVISORY UNTIL 8 PM CDT THIS EVENING FOR CLARK-SCOTLAND.
&&
$$
UPDATE...05
SYNOPSIS...SHEETS
SHORT TERM...SHEETS
LONG TERM...08
AVIATION...05
AREA FORECAST DISCUSSION
NWS QUAD CITIES IA IL
1137 AM CDT MON AUG 25 2014
.UPDATE...
ISSUED AT 1121 AM CDT MON AUG 25 2014
HAVE UPDATED TO BUMP UP POPS AND EXTEND THROUGH THE AFTERNOON AS
LOOKING LIKELY TO SEE AT LEAST SCATTERED ACTIVITY PERSIST ALL
DAY MOSTLY NORTH OF I-80 WITH MORE ISOLATED OVER SOUTHEAST IA.
THIS ACTIVITY WILL BE AIDED BY WEAK SURFACE LOW NORTHEAST OF
DES MOINES AND INTERACTING WITH OUTFLOW BOUNDARIES...WITH MAIN
BOUNDARY OF NOTE ARCING JUST SOUTH OF I-80. WITH LINGERING
CONVECTION AND DEBRIS CLOUDS HAVE TWEAKED HIGHS DOWN OVER PORTIONS
OF NORTHEAST IA AND FAR NORTHWEST IL INTO THE MID 80S... BUT
WITH DUBUQUE STILL AT 71 DEGS AT 11 AM WOULD NOT BE SURPRISED TO
SEE SOME AREAS STRUGGLE TO HIT 80 OR LOWER 80S FAR NORTH. OTHERWISE
CURRENT HEAT ADVISORY HEADLINE ON TRACK FROM AROUND QUAD CITIES
SOUTH/EAST WITH FEW LOCATIONS ALREADY AT 90 DEGS AND HEAT INDEX
READINGS APPROACHING 100.
LOOKING FURTHER AHEAD TO TONIGHT AND TUESDAY... COLD FRONT THROUGH
NORTHWEST IA MOVING A BIT FASTER THAN MODELS AND LIKELY TO BE
LOCATED SOUTH OF THE CWA TUESDAY MORNING. ANTICIPATE POTENTIAL FOR
MORE ORGANIZED CONVECTION MOVING ACROSS NORTH 1/3-1/2 LATER
TONIGHT INTO TUE AM. IF TRENDS PERSIST THEN GOING FORECAST HIGHS
TOMORROW ARE LIKELY TOO WARM...POSSIBLY BY AS MUCH AS 5-10 DEGS
NOTING THAT AS WE ARE APPROACHING THE NOON HOUR TEMPS ARE IN THE
UPPER 60S TO LOWER 70S IN NORTHWEST IA POST FRONTAL WITH SUNSHINE.
THUS WITH CLOUDS AND RAIN COULD EASILY SEE AREAS STUCK IN THE 70S
ALL DAY TOMORROW. HAVE NOT MADE CHANGES YET AS STILL EVALUATING
MODEL SUITE... AND WILL HAVE MORE ON THIS WITH AFTERNOON DISCO.
UPDATED GRIDS/ZFP/PFM HAVE BEEN ISSUED.
&&
.SYNOPSIS...
ISSUED AT 334 AM CDT MON AUG 25 2014
THUNDERSTORMS HAVE DEVELOPED EARLY THIS MORNING ALONG AND AHEAD OF
THE SURFACE FRONT EXTENDING ROUGHLY FROM WESTERN LAKE SUPERIOR SW
ACROSS WESTERN WI...SW MN...INTO W CENTRAL IA. THIS WAS ALONG AN
AXIS OF HIGH THETAE INDICATED BY 850 MB DEWPOINTS OF 14 TO 16 C FROM
NORTHEAST KS INTO SW ONTARIO AT 00Z...WITH CONVERGENCE ASSISTED
BY 35KT TO 40 KT SW WINDS AT 850 MB. THIS MOISTURE WAS BEING
PULLED NORTHWARD BY A STRONG SURFACE AND UPPER LEVEL LOW SEEN ON
WV IMAGERY ALONG THE ND/MANITOBA BORDER. AT 3 AM...THE LEADING
LINE OF SCATTERED THUNDERSTORMS WAS MOVING INTO BUCHANAN AND
BENTON COUNTIES...INTO A VERY HUMID AIRMASS WITH DEWPOINTS IN THE
LOWER TO MID 70S AND AIR TEMPERATURES IN THE MID TO UPPER 70S.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 334 AM CDT MON AUG 25 2014
FORECAST CHALLENGES CENTER ON THUNDERSTORMS THIS MORNING AND AGAIN
TONIGHT...AND HEAT HEADLINES TODAY AS THE HOT AND HUMID CONDITIONS
PERSIST OVER THE REGION. IN THE NEAR TERM...A SEMI-LINEAR MCS WILL
LIKELY MOVE ACROSS THE FORECAST AREA MAINLY NORTH OF I-80...DRIVEN
BY A WEAK SHORTWAVE FLOW IN THE NW FLOW ALOFT. WHILE NO INDIVIDUAL
FORECAST MODEL HAS HAD A GOOD HANDLE ON TRENDS OVERNIGHT...THE
HIGH RES WRF AND RAP MODELS APPEAR TO HAVE THE BEST HANDLE ON THE
CONVECTION ENTERING THE NORTH. THESE HAVE THE THUNDERSTORMS ADVANCING
THROUGH THE NORTH OVER THE NEXT SEVERAL HOURS AND THEN DISSIPATING
BY NOON...AND HAVE TRENDED THE FORECAST ACCORDINGLY. THE LATEST
RAP IS ALONE WITH DEVELOPING THUNDERSTORMS IN THE HIGH MUCAPE
AXIS FURTHER SE...OVER 4000 J/KG...OVER W CENTRAL IL TOWARD
SUNRISE...WHICH WHILE NOT IN THE CURRENT FORECAST CANNOT BE
ENTIRELY RULED AND WILL WATCH TRENDS CLOSELY.
OTHERWISE...THIS SHOULD BE FOLLOWED BY CLEARING SKIES AND A RETURN
TO THE HEAT AND HUMIDITY SEEN OVER THE AREA YESTERDAY. DUE TO
UNCERTAINTIES IN THE TIMING OF THE DISSIPATING MCS IN THE NORTH AND
POSSIBLE DEBRIS CLOUDS FROM STORMS IN THE PLAINS...ALONG WITH 850 MB
TEMPERATURES PROGGED ABOUT 1 DEGREE COOLER...HAVE TRENDED HIGHS A
DEGREE OR TWO COOLER THAN SUNDAY...WITH UPPER 80S NW TO LOWER 90S
CENTRAL AND SOUTH. DEWPOINTS WILL HOLD IN THE LOWER TO MID 70S AND
POSSIBLY TOUCH THE UPPER 70S AT TIMES LATE IN THE DAY. THIS
COMBINATION WILL SEND HEAT INDEX VALUES TO JUST ABOVE 100 ACROSS
THE SOUTH AND WILL KEEP THE PREVIOUS HEAT ADVISORY CONFIGURATION
IN PLACE.
TONIGHT...THE SETUP WILL BE FAVORABLE FOR ANOTHER MCS AS THE SURFACE
FRONT SLOWLY ADVANCES THROUGH THE FORECAST AREA AND MODEST
CONVERGENCE OCCURS IN THE 850 MB THETAE AXIS AS IT SHIFTS OVERHEAD.
HAVE KEPT LIKELY POPS IN THE NORTH WITH SLIGHT TO LOW END CHANCE
POPS IN THE SOUTH TOWARD MORNING. THE MAIN THREAT WILL BE LOCALLY
HEAVY RAINFALL. IT WILL BE ANOTHER WARM AND VERY HUMID NIGHT WITH
TEMPERATURES AND DEWPOINTS IN THE 70S...EXCEPT IN THE FAR NW...WHERE
THE CURRENT FRONTAL TIMING SUGGESTS READINGS LOWERING INTO THE
UPPER 60S.
.LONG TERM...(TUESDAY THROUGH SUNDAY)
ISSUED AT 334 AM CDT MON AUG 25 2014
AN ORGANIZED THUNDERSTORM COMPLEX SHOULD MOVE INTO THE AREA TUESDAY
MORNING AND DISSIPATE DURING THE MORNING. BOUNDARIES LEFT OVER FROM
THIS COMPLEX COMBINED WITH A WEAK FRONT MOVING THROUGH THE AREA WILL
PROVIDE THE FOCUS FOR NEW CONVECTION TUESDAY AFTERNOON AND EVENING.
HIGH MOISTURE LEVELS IN THE LOWER ATMOSPHERE MEANS ANY STORM WILL BE
CAPABLE OF PRODUCING LOCALLY HEAVY RAINFALL.
CLOUD COVER AND RAIN WILL PLAY INTO HOW WARM IT WILL GET ON TUESDAY.
THE SOUTHEAST HALF MAY SEE TEMPERATURES AROUND 90 WITH HEAT INDEX
READINGS IN THE UPPER 90S TO JUST OVER 100.
ANOTHER THUNDERSTORM COMPLEX IS EXPECTED TO DEVELOP IN WESTERN IOWA
TUESDAY EVENING AND THEN MOVE MAINLY EAST OVERNIGHT INTO WEDNESDAY
MORNING. THIS STORM COMPLEX SHOULD ARRIVE IN THE WESTERN THIRD OF
THE CWFA IN THE PRE-DAWN HOURS AND SLOWLY DISSIPATE ACROSS THE AREA
WEDNESDAY MORNING. LOCALLY HEAVY RAINFALL WILL BE POSSIBLE FROM THE
STORMS DUE TO HIGH MOISTURE LEVELS.
LIKE TUESDAY...BOUNDARIES LEFT OVER FROM THE WEDNESDAY STORM COMPLEX
WILL PROVIDE THE FOCUS FOR NEW CONVECTION WEDNESDAY AFTERNOON AND
EVENING.
SIGNALS FROM THE MODELS SUGGEST YET ANOTHER THUNDERSTORM COMPLEX
WILL DEVELOP IN WESTERN IOWA WEDNESDAY EVENING AND MOVE GENERALLY
EAST OVERNIGHT AND ARRIVE IN THE WESTERN THIRD OF THE AREA IN THE
PRE-DAWN HOURS. LOCALLY HEAVY RAINFALL MAY BE POSSIBLE FROM SOME OF
THE STRONGER STORMS.
THURSDAY ON...
THE MODEL CONSENSUS HAS CHANCE POPS IN EACH 12 HOUR PERIOD FROM
THURSDAY THROUGH SATURDAY NIGHT. TEMPERATURES SHOULD BE NEAR NORMAL.
ON SUNDAY...THE MODEL CONSENSUS HAS SLIGHT CHANCE TO LOW CHANCE POPS.
THE LARGE SCALE PICTURE SUGGESTS THE WEATHER PATTERN WILL REMAIN
FAIRLY ACTIVE WITH A FRONT STALLED OUT JUST SOUTH OF THE AREA. IT
WILL NOT RAIN CONTINUOUSLY THE ENTIRE TIME. THERE WILL BE PERIODS OF
DRY WEATHER THAT MAY LAST 6 OR 12 HOURS.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z TUESDAY MORNING)
ISSUED AT 645 AM CDT MON AUG 25 2014
A SLOW MOVING AXIS OF THUNDERSTORMS OVER NORTHEAST IOWA MAY
BRIEFLY IMPACT THE CID AND DBQ TERMINALS EARLY THIS MORNING. FOG
AND A FEW AREAS OF LOW CLOUDS WILL IMPACT MOST OF THE TERMINALS
WITH PERIODS OF MVFR CONDITIONS UNTIL MID MORNING.
OTHERWISE...TODAY WILL BE MAINLY VFR WITH VERY HUMID CONDITIONS.
ANOTHER ROUND OF THUNDERSTORMS IS EXPECTED TO MOVE THROUGH EASTERN
IOWA AND NORTHWEST ILLINOIS LATE TONIGHT AS A COOL FRONT SLOWLY
DROPS SOUTH THROUGH THE AREA. THIS IS MOST LIKELY TO AFFECT THE
CID...DBQ AND MLI TERMINALS...WHERE PROB30 GROUPS COVER THE
POTENTIAL FOR NOW. ALSO...LIGHT WINDS AND LINGERING LOW LEVEL
MOISTURE WILL ALSO LEAD TO MVFR FOG...WHICH IS ALSO INCLUDED FOR
THE LATE NIGHT AND EARLY MORNING PERIODS.
&&
.DVN WATCHES/WARNINGS/ADVISORIES...
IA...HEAT ADVISORY UNTIL 8 PM CDT THIS EVENING FOR LOUISA-MUSCATINE-
SCOTT.
HEAT ADVISORY UNTIL 8 PM CDT THIS EVENING FOR DES MOINES-HENRY
IA-LEE-VAN BUREN.
IL...HEAT ADVISORY UNTIL 8 PM CDT THIS EVENING FOR BUREAU-HENRY IL-
MERCER-PUTNAM-ROCK ISLAND-WHITESIDE.
HEAT ADVISORY UNTIL 8 PM CDT THIS EVENING FOR HANCOCK-HENDERSON-
MCDONOUGH-WARREN.
MO...HEAT ADVISORY UNTIL 8 PM CDT THIS EVENING FOR CLARK-SCOTLAND.
&&
$$
UPDATE...05
SYNOPSIS...SHEETS
SHORT TERM...SHEETS
LONG TERM...08
AVIATION...SHEETS
AREA FORECAST DISCUSSION
NWS QUAD CITIES IA IL
647 AM CDT MON AUG 25 2014
.UPDATE...
ISSUED AT 645 AM CDT MON AUG 25 2014
HAVE UPDATED THE FORECAST TO ADD EARLY MORNING FOG AND LOW CLOUDS
OVER THE FAR EAST...WHERE SURFACE REPORTS AND SATELLITE FOG
CHANNEL SHOWED THE EDGE OF A LARGER DECK OVER NE IL EDGING INTO
THE NW IL COUNTIES AND OCCASIONALLY LOWERING VISIBILITIES TO LESS
THAN 1 MILE. ELSEWHERE...THUNDERSTORMS CONTINUE TO TRAIN IN A SW
TO NE FASHION...PARALLEL TO THE UPPER LEVEL FLOW FROM CENTRAL IA
INTO SW WI. SO FAR...THE STORMS HAVE REMAINED MAINLY NW OF A LINE
FROM BELLE PLAINE THROUGH CENTRAL CITY TO DUBUQUE. RADAR ESTIMATES
INDICATE RAINFALL AMOUNTS OF A QUARTER INCH TO NEARLY 1.5 INCHES
HAS FALLEN OVER THE PAST SEVERAL HOURS IN THIS AREA.
CELLS SHOULD CONTINUE TO TRAIN ALONG THIS AXIS...AND POSSIBLY
SHIFT A BIT TO THE SOUTHEAST BEFORE DISSIPATING WITH THE LOSS OF
UPPER LEVEL SUPPORT AND THE DIURNAL WANING OF THE LOW LEVEL JET
THIS MORNING. EVEN WITH A POSSIBLE ADDITIONAL 1 INCH OF
RAIN...NOT ANTICIPATING ANY SIGNIFICANT HYDRO ISSUES AS FLASH
FLOOD GUIDANCE VALUES ARE MAINLY OVER 3 INCHES PER 3 HOURS IN THIS
AREA DUE TO THE RECENT DRY WEATHER.
&&
.SYNOPSIS...
ISSUED AT 334 AM CDT MON AUG 25 2014
THUNDERSTORMS HAVE DEVELOPED EARLY THIS MORNING ALONG AND AHEAD OF
THE SURFACE FRONT EXTENDING ROUGHLY FROM WESTERN LAKE SUPERIOR SW
ACROSS WESTERN WI...SW MN...INTO W CENTRAL IA. THIS WAS ALONG AN
AXIS OF HIGH THETAE INDICATED BY 850 MB DEWPOINTS OF 14 TO 16 C FROM
NORTHEAST KS INTO SW ONTARIO AT 00Z...WITH CONVERGENCE ASSISTED
BY 35KT TO 40 KT SW WINDS AT 850 MB. THIS MOISTURE WAS BEING
PULLED NORTHWARD BY A STRONG SURFACE AND UPPER LEVEL LOW SEEN ON
WV IMAGERY ALONG THE ND/MANITOBA BORDER. AT 3 AM...THE LEADING
LINE OF SCATTERED THUNDERSTORMS WAS MOVING INTO BUCHANAN AND
BENTON COUNTIES...INTO A VERY HUMID AIRMASS WITH DEWPOINTS IN THE
LOWER TO MID 70S AND AIR TEMPERATURES IN THE MID TO UPPER 70S.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 334 AM CDT MON AUG 25 2014
FORECAST CHALLENGES CENTER ON THUNDERSTORMS THIS MORNING AND AGAIN
TONIGHT...AND HEAT HEADLINES TODAY AS THE HOT AND HUMID CONDITIONS
PERSIST OVER THE REGION. IN THE NEAR TERM...A SEMI-LINEAR MCS WILL
LIKELY MOVE ACROSS THE FORECAST AREA MAINLY NORTH OF I-80...DRIVEN
BY A WEAK SHORTWAVE FLOW IN THE NW FLOW ALOFT. WHILE NO INDIVIDUAL
FORECAST MODEL HAS HAD A GOOD HANDLE ON TRENDS OVERNIGHT...THE
HIGH RES WRF AND RAP MODELS APPEAR TO HAVE THE BEST HANDLE ON THE
CONVECTION ENTERING THE NORTH. THESE HAVE THE THUNDERSTORMS ADVANCING
THROUGH THE NORTH OVER THE NEXT SEVERAL HOURS AND THEN DISSIPATING
BY NOON...AND HAVE TRENDED THE FORECAST ACCORDINGLY. THE LATEST
RAP IS ALONE WITH DEVELOPING THUNDERSTORMS IN THE HIGH MUCAPE
AXIS FURTHER SE...OVER 4000 J/KG...OVER W CENTRAL IL TOWARD
SUNRISE...WHICH WHILE NOT IN THE CURRENT FORECAST CANNOT BE
ENTIRELY RULED AND WILL WATCH TRENDS CLOSELY.
OTHERWISE...THIS SHOULD BE FOLLOWED BY CLEARING SKIES AND A RETURN
TO THE HEAT AND HUMIDITY SEEN OVER THE AREA YESTERDAY. DUE TO
UNCERTAINTIES IN THE TIMING OF THE DISSIPATING MCS IN THE NORTH AND
POSSIBLE DEBRIS CLOUDS FROM STORMS IN THE PLAINS...ALONG WITH 850 MB
TEMPERATURES PROGGED ABOUT 1 DEGREE COOLER...HAVE TRENDED HIGHS A
DEGREE OR TWO COOLER THAN SUNDAY...WITH UPPER 80S NW TO LOWER 90S
CENTRAL AND SOUTH. DEWPOINTS WILL HOLD IN THE LOWER TO MID 70S AND
POSSIBLY TOUCH THE UPPER 70S AT TIMES LATE IN THE DAY. THIS
COMBINATION WILL SEND HEAT INDEX VALUES TO JUST ABOVE 100 ACROSS
THE SOUTH AND WILL KEEP THE PREVIOUS HEAT ADVISORY CONFIGURATION
IN PLACE.
TONIGHT...THE SETUP WILL BE FAVORABLE FOR ANOTHER MCS AS THE SURFACE
FRONT SLOWLY ADVANCES THROUGH THE FORECAST AREA AND MODEST
CONVERGENCE OCCURS IN THE 850 MB THETAE AXIS AS IT SHIFTS OVERHEAD.
HAVE KEPT LIKELY POPS IN THE NORTH WITH SLIGHT TO LOW END CHANCE
POPS IN THE SOUTH TOWARD MORNING. THE MAIN THREAT WILL BE LOCALLY
HEAVY RAINFALL. IT WILL BE ANOTHER WARM AND VERY HUMID NIGHT WITH
TEMPERATURES AND DEWPOINTS IN THE 70S...EXCEPT IN THE FAR NW...WHERE
THE CURRENT FRONTAL TIMING SUGGESTS READINGS LOWERING INTO THE
UPPER 60S.
.LONG TERM...(TUESDAY THROUGH SUNDAY)
ISSUED AT 334 AM CDT MON AUG 25 2014
AN ORGANIZED THUNDERSTORM COMPLEX SHOULD MOVE INTO THE AREA TUESDAY
MORNING AND DISSIPATE DURING THE MORNING. BOUNDARIES LEFT OVER FROM
THIS COMPLEX COMBINED WITH A WEAK FRONT MOVING THROUGH THE AREA WILL
PROVIDE THE FOCUS FOR NEW CONVECTION TUESDAY AFTERNOON AND EVENING.
HIGH MOISTURE LEVELS IN THE LOWER ATMOSPHERE MEANS ANY STORM WILL BE
CAPABLE OF PRODUCING LOCALLY HEAVY RAINFALL.
CLOUD COVER AND RAIN WILL PLAY INTO HOW WARM IT WILL GET ON TUESDAY.
THE SOUTHEAST HALF MAY SEE TEMPERATURES AROUND 90 WITH HEAT INDEX
READINGS IN THE UPPER 90S TO JUST OVER 100.
ANOTHER THUNDERSTORM COMPLEX IS EXPECTED TO DEVELOP IN WESTERN IOWA
TUESDAY EVENING AND THEN MOVE MAINLY EAST OVERNIGHT INTO WEDNESDAY
MORNING. THIS STORM COMPLEX SHOULD ARRIVE IN THE WESTERN THIRD OF
THE CWFA IN THE PRE-DAWN HOURS AND SLOWLY DISSIPATE ACROSS THE AREA
WEDNESDAY MORNING. LOCALLY HEAVY RAINFALL WILL BE POSSIBLE FROM THE
STORMS DUE TO HIGH MOISTURE LEVELS.
LIKE TUESDAY...BOUNDARIES LEFT OVER FROM THE WEDNESDAY STORM COMPLEX
WILL PROVIDE THE FOCUS FOR NEW CONVECTION WEDNESDAY AFTERNOON AND
EVENING.
SIGNALS FROM THE MODELS SUGGEST YET ANOTHER THUNDERSTORM COMPLEX
WILL DEVELOP IN WESTERN IOWA WEDNESDAY EVENING AND MOVE GENERALLY
EAST OVERNIGHT AND ARRIVE IN THE WESTERN THIRD OF THE AREA IN THE
PRE-DAWN HOURS. LOCALLY HEAVY RAINFALL MAY BE POSSIBLE FROM SOME OF
THE STRONGER STORMS.
THURSDAY ON...
THE MODEL CONSENSUS HAS CHANCE POPS IN EACH 12 HOUR PERIOD FROM
THURSDAY THROUGH SATURDAY NIGHT. TEMPERATURES SHOULD BE NEAR NORMAL.
ON SUNDAY...THE MODEL CONSENSUS HAS SLIGHT CHANCE TO LOW CHANCE POPS.
THE LARGE SCALE PICTURE SUGGESTS THE WEATHER PATTERN WILL REMAIN
FAIRLY ACTIVE WITH A FRONT STALLED OUT JUST SOUTH OF THE AREA. IT
WILL NOT RAIN CONTINUOUSLY THE ENTIRE TIME. THERE WILL BE PERIODS OF
DRY WEATHER THAT MAY LAST 6 OR 12 HOURS.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z TUESDAY MORNING)
ISSUED AT 645 AM CDT MON AUG 25 2014
A SLOW MOVING AXIS OF THUNDERSTORMS OVER NORTHEAST IOWA MAY
BRIEFLY IMPACT THE CID AND DBQ TERMINALS EARLY THIS MORNING. FOG
AND A FEW AREAS OF LOW CLOUDS WILL IMPACT MOST OF THE TERMINALS
WITH PERIODS OF MVFR CONDITIONS UNTIL MID MORNING.
OTHERWISE...TODAY WILL BE MAINLY VFR WITH VERY HUMID CONDITIONS.
ANOTHER ROUND OF THUNDERSTORMS IS EXPECTED TO MOVE THROUGH EASTERN
IOWA AND NORTHWEST ILLINOIS LATE TONIGHT AS A COOL FRONT SLOWLY
DROPS SOUTH THROUGH THE AREA. THIS IS MOST LIKELY TO AFFECT THE
CID...DBQ AND MLI TERMINALS...WHERE PROB30 GROUPS COVER THE
POTENTIAL FOR NOW. ALSO...LIGHT WINDS AND LINGERING LOW LEVEL
MOISTURE WILL ALSO LEAD TO MVFR FOG...WHICH IS ALSO INCLUDED FOR
THE LATE NIGHT AND EARLY MORNING PERIODS.
&&
.DVN WATCHES/WARNINGS/ADVISORIES...
IA...HEAT ADVISORY FROM NOON TODAY TO 8 PM CDT THIS EVENING FOR
LOUISA-MUSCATINE-SCOTT.
HEAT ADVISORY UNTIL 8 PM CDT THIS EVENING FOR DES MOINES-HENRY
IA-LEE-VAN BUREN.
IL...HEAT ADVISORY FROM NOON TODAY TO 8 PM CDT THIS EVENING FOR
BUREAU-HENRY IL-MERCER-PUTNAM-ROCK ISLAND-WHITESIDE.
HEAT ADVISORY UNTIL 8 PM CDT THIS EVENING FOR HANCOCK-HENDERSON-
MCDONOUGH-WARREN.
MO...HEAT ADVISORY UNTIL 8 PM CDT THIS EVENING FOR CLARK-SCOTLAND.
&&
$$
UPDATE...SHEETS
SYNOPSIS...SHEETS
SHORT TERM...SHEETS
LONG TERM...08
AVIATION...SHEETS
AREA FORECAST DISCUSSION
NWS QUAD CITIES IA IL
335 AM CDT MON AUG 25 2014
.SYNOPSIS...
ISSUED AT 334 AM CDT MON AUG 25 2014
THUNDERSTORMS HAVE DEVELOPED EARLY THIS MORNING ALONG AND AHEAD OF
THE SURFACE FRONT EXTENDING ROUGHLY FROM WESTERN LAKE SUPERIOR SW
ACROSS WESTERN WI...SW MN...INTO W CENTRAL IA. THIS WAS ALONG AN
AXIS OF HIGH THETAE INDICATED BY 850 MB DEWPOINTS OF 14 TO 16 C FROM
NORTHEAST KS INTO SW ONTARIO AT 00Z...WITH CONVERGENCE ASSISTED
BY 35KT TO 40 KT SW WINDS AT 850 MB. THIS MOISTURE WAS BEING
PULLED NORTHWARD BY A STRONG SURFACE AND UPPER LEVEL LOW SEEN ON
WV IMAGERY ALONG THE ND/MANITOBA BORDER. AT 3 AM...THE LEADING
LINE OF SCATTERED THUNDERSTORMS WAS MOVING INTO BUCHANAN AND
BENTON COUNTIES...INTO A VERY HUMID AIRMASS WITH DEWPOINTS IN THE
LOWER TO MID 70S AND AIR TEMPERATURES IN THE MID TO UPPER 70S.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 334 AM CDT MON AUG 25 2014
FORECAST CHALLENGES CENTER ON THUNDERSTORMS THIS MORNING AND AGAIN
TONIGHT...AND HEAT HEADLINES TODAY AS THE HOT AND HUMID CONDITIONS
PERSIST OVER THE REGION. IN THE NEAR TERM...A SEMI-LINEAR MCS WILL
LIKELY MOVE ACROSS THE FORECAST AREA MAINLY NORTH OF I-80...DRIVEN
BY A WEAK SHORTWAVE FLOW IN THE NW FLOW ALOFT. WHILE NO INDIVIDUAL
FORECAST MODEL HAS HAD A GOOD HANDLE ON TRENDS OVERNIGHT...THE
HIGH RES WRF AND RAP MODELS APPEAR TO HAVE THE BEST HANDLE ON THE
CONVECTION ENTERING THE NORTH. THESE HAVE THE THUNDERSTORMS ADVANCING
THROUGH THE NORTH OVER THE NEXT SEVERAL HOURS AND THEN DISSIPATING
BY NOON...AND HAVE TRENDED THE FORECAST ACCORDINGLY. THE LATEST
RAP IS ALONE WITH DEVELOPING THUNDERSTORMS IN THE HIGH MUCAPE
AXIS FURTHER SE...OVER 4000 J/KG...OVER W CENTRAL IL TOWARD
SUNRISE...WHICH WHILE NOT IN THE CURRENT FORECAST CANNOT BE
ENTIRELY RULED AND WILL WATCH TRENDS CLOSELY.
OTHERWISE...THIS SHOULD BE FOLLOWED BY CLEARING SKIES AND A RETURN
TO THE HEAT AND HUMIDITY SEEN OVER THE AREA YESTERDAY. DUE TO
UNCERTAINTIES IN THE TIMING OF THE DISSIPATING MCS IN THE NORTH AND
POSSIBLE DEBRIS CLOUDS FROM STORMS IN THE PLAINS...ALONG WITH 850 MB
TEMPERATURES PROGGED ABOUT 1 DEGREE COOLER...HAVE TRENDED HIGHS A
DEGREE OR TWO COOLER THAN SUNDAY...WITH UPPER 80S NW TO LOWER 90S
CENTRAL AND SOUTH. DEWPOINTS WILL HOLD IN THE LOWER TO MID 70S AND
POSSIBLY TOUCH THE UPPER 70S AT TIMES LATE IN THE DAY. THIS
COMBINATION WILL SEND HEAT INDEX VALUES TO JUST ABOVE 100 ACROSS
THE SOUTH AND WILL KEEP THE PREVIOUS HEAT ADVISORY CONFIGURATION
IN PLACE.
TONIGHT...THE SETUP WILL BE FAVORABLE FOR ANOTHER MCS AS THE SURFACE
FRONT SLOWLY ADVANCES THROUGH THE FORECAST AREA AND MODEST
CONVERGENCE OCCURS IN THE 850 MB THETAE AXIS AS IT SHIFTS OVERHEAD.
HAVE KEPT LIKELY POPS IN THE NORTH WITH SLIGHT TO LOW END CHANCE
POPS IN THE SOUTH TOWARD MORNING. THE MAIN THREAT WILL BE LOCALLY
HEAVY RAINFALL. IT WILL BE ANOTHER WARM AND VERY HUMID NIGHT WITH
TEMPERATURES AND DEWPOINTS IN THE 70S...EXCEPT IN THE FAR NW...WHERE
THE CURRENT FRONTAL TIMING SUGGESTS READINGS LOWERING INTO THE
UPPER 60S.
.LONG TERM...(TUESDAY THROUGH SUNDAY)
ISSUED AT 334 AM CDT MON AUG 25 2014
AN ORGANIZED THUNDERSTORM COMPLEX SHOULD MOVE INTO THE AREA TUESDAY
MORNING AND DISSIPATE DURING THE MORNING. BOUNDARIES LEFT OVER FROM
THIS COMPLEX COMBINED WITH A WEAK FRONT MOVING THROUGH THE AREA WILL
PROVIDE THE FOCUS FOR NEW CONVECTION TUESDAY AFTERNOON AND EVENING.
HIGH MOISTURE LEVELS IN THE LOWER ATMOSPHERE MEANS ANY STORM WILL BE
CAPABLE OF PRODUCING LOCALLY HEAVY RAINFALL.
CLOUD COVER AND RAIN WILL PLAY INTO HOW WARM IT WILL GET ON TUESDAY.
THE SOUTHEAST HALF MAY SEE TEMPERATURES AROUND 90 WITH HEAT INDEX
READINGS IN THE UPPER 90S TO JUST OVER 100.
ANOTHER THUNDERSTORM COMPLEX IS EXPECTED TO DEVELOP IN WESTERN IOWA
TUESDAY EVENING AND THEN MOVE MAINLY EAST OVERNIGHT INTO WEDNESDAY
MORNING. THIS STORM COMPLEX SHOULD ARRIVE IN THE WESTERN THIRD OF
THE CWFA IN THE PRE-DAWN HOURS AND SLOWLY DISSIPATE ACROSS THE AREA
WEDNESDAY MORNING. LOCALLY HEAVY RAINFALL WILL BE POSSIBLE FROM THE
STORMS DUE TO HIGH MOISTURE LEVELS.
LIKE TUESDAY...BOUNDARIES LEFT OVER FROM THE WEDNESDAY STORM COMPLEX
WILL PROVIDE THE FOCUS FOR NEW CONVECTION WEDNESDAY AFTERNOON AND
EVENING.
SIGNALS FROM THE MODELS SUGGEST YET ANOTHER THUNDERSTORM COMPLEX
WILL DEVELOP IN WESTERN IOWA WEDNESDAY EVENING AND MOVE GENERALLY
EAST OVERNIGHT AND ARRIVE IN THE WESTERN THIRD OF THE AREA IN THE
PRE-DAWN HOURS. LOCALLY HEAVY RAINFALL MAY BE POSSIBLE FROM SOME OF
THE STRONGER STORMS.
THURSDAY ON...
THE MODEL CONSENSUS HAS CHANCE POPS IN EACH 12 HOUR PERIOD FROM
THURSDAY THROUGH SATURDAY NIGHT. TEMPERATURES SHOULD BE NEAR NORMAL.
ON SUNDAY...THE MODEL CONSENSUS HAS SLIGHT CHANCE TO LOW CHANCE POPS.
THE LARGE SCALE PICTURE SUGGESTS THE WEATHER PATTERN WILL REMAIN
FAIRLY ACTIVE WITH A FRONT STALLED OUT JUST SOUTH OF THE AREA. IT
WILL NOT RAIN CONTINUOUSLY THE ENTIRE TIME. THERE WILL BE PERIODS OF
DRY WEATHER THAT MAY LAST 6 OR 12 HOURS.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT)
ISSUED AT 1125 PM CDT SUN AUG 24 2014
AN APPROACHING FRONT BRINGS THE THREAT FOR SHOWERS AND
THUNDERSTORMS TO EASTERN IOWA AFTER 08Z LATE TONIGHT. IT IS NOT
CERTAIN THAT THEY WILL IMPACT THE AREA...AND A VCSH IS CONTINUED
TO BE USED TO DESCRIBE THIS LATE NIGHT THREAT WITH TEMPORARY 5SM
TSRA POSSIBLE AT BOTH CID AND DBQ. IF THE LINE OF STORMS VERIFY
OVERNIGHT IN EASTERN IOWA...MVFR CONDITIONS ARE LIKELY TO OCCUR
ESPECIALLY AT CID AND DBQ AND POSSIBLY AT MLI. OTHERWISE...LATE NIGHT
AND EARLY MORNING MVFR FOG IS LIKELY AT ALL SITES DUE TO THE VERY
MOIST AIR MASS IN PLACE IN THE REGION. AFTER 15Z MONDAY...A RETURN
TO HOT VFR WEATHER IS EXPECTED. SOUTH TO SOUTHEAST WINDS OF 5 TO 9
KTS ARE EXPECTED THROUGH THE PERIOD. ANOTHER THREAT FOR A SHOWER
OR STORM WILL ARRIVE BY LATE AFTERNOON MONDAY AND CONTINUE INTO
MONDAY NIGHT.
ERVIN
&&
.DVN WATCHES/WARNINGS/ADVISORIES...
IA...HEAT ADVISORY FROM NOON TODAY TO 8 PM CDT THIS EVENING FOR
LOUISA-MUSCATINE-SCOTT.
HEAT ADVISORY UNTIL 8 PM CDT THIS EVENING FOR DES MOINES-HENRY
IA-LEE-VAN BUREN.
IL...HEAT ADVISORY FROM NOON TODAY TO 8 PM CDT THIS EVENING FOR
BUREAU-HENRY IL-MERCER-PUTNAM-ROCK ISLAND-WHITESIDE.
HEAT ADVISORY UNTIL 8 PM CDT THIS EVENING FOR HANCOCK-HENDERSON-
MCDONOUGH-WARREN.
MO...HEAT ADVISORY UNTIL 8 PM CDT THIS EVENING FOR CLARK-SCOTLAND.
&&
$$
SYNOPSIS...SHEETS
SHORT TERM...SHEETS
LONG TERM...08
AVIATION...ERVIN
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
224 AM CDT Mon Aug 25 2014
...Updated long term section...
.SHORT TERM...(Today and tonight)
ISSUED AT 155 AM CDT MON AUG 25 2014
A wedge of warm 850mb to 700mb temperatures that was located just
south of a surface boundary which extended from the Oklahoma
panhandle to northeast Kansas at 00z Monday will lift north today
and by 00z Tuesday this warm air will be located across most of
western and south central Kansas. Based on the the forecast mixing
height and the 00z Tuesday temperatures in the 850mb to 700mb
level from the NAM and GFS it will be another day with highs in
the upper 90s to near 100 degrees across most of western and south
central Kansas.
In addition to the warming temperatures 700mb moisture will also
be improving across central and north central Kansas which may
give rise to some afternoon convection as CAPE values increase to
1000 to 2000 j/kg, especially across northern Kansas. At this time
it appears the better forcing and instability late today along
with the better low level moisture will be near/north the surface
boundary in north central Kansas so will focus late day convection
around and north of the interstate 70 corridor with more widely
scattered storms being possible further south.
Tonight warm air advection and moisture advection improves near
the nose of a developing low level jet. This will be just north of
a surface boundary that will remain nearly stationary early
tonight across west central and north central Kansas. At the same
time an upper level trough is forecast to cross northwest Kansas.
As a result will increase the chances for convection across west
central and north central Kansas, especially north of where the
+12c to +14c 700mb temperature gradient is forecast to be located
by the NAM and GFS at 06z and 12z Tuesday. Preciptable water
values Monday night are forecast to range from 1.5 to 1.75 across
northern Kansas so some storms tonight may produce periods of
heavy rainfall. Also am unable to rule out the chance for some
storms becoming severe Monday evening north of the interstate 70
corridor base on 0-6km shear of 30 to 40 knots and CAPE values
ranging from 1500 to near 3000 j/kg at 00z Tuesday from the NAM
and GFS. Main hazard at this time appears to be quarter size hail
and wind gusts of 60 mph or greater.
.LONG TERM...(Tuesday through Sunday)
ISSUED AT 223 AM CDT MON AUG 25 2014
An upper level low will trek from the Pacific northwest Monday to
the Central Plains by Friday before exiting the area this weekend.
Mid to upper levels of the atmosphere will saturate as this system
approaches bringing increasing cloudiness to western Kansas. Towards
the surface, a frontal boundary is expected to be positioned across
west central Kansas Tuesday before lifting northward to northern
Kansas and Nebraska Wednesday into Thursday. This frontal boundary
will be the main focal point where thunderstorms are expected to
develop. There could also be storms developing along the higher
terrain across eastern Colorado before moving into western Kansas
later on. A cold front is then progged to move through the area
Thursday with wrap around moisture in place Friday. Thunderstorm
chances envelop the CWA Wednesday night through Friday before
tapering off Friday night. A drier pattern then sits up for this
weekend with partly cloudy skies expected. As for temperatures,
highs will start out in the 90s Tuesday and Wednesday before cooling
off into the 80s Thursday through Saturday. Highs Sunday look to top
out in the lower 90s. Lows are forecasted to range from the mid 60s
across west central Kansas to lower 70s across south central Kansas
Tuesday through Thursday morning before cooling off into the 60s
Friday into this weekend.
&&
.AVIATION...(For the 06Z TAFS through 06Z Monday night)
ISSUED AT 1205 AM CDT MON AUG 25 2014
A weak surface boundary will lift north across western Kansas
overnight. As this boundary moves into west central and north
central Kansas the surface winds will become south southeast at
around 10 knots by 12z Monday. Based on 03z verification from the
NAM and HRRR will stay close to these models on timing of the wind
shift overnight. Southerly winds will increase to around 15 knots
by the early afternoon. BUFR soundings indicating VRF conditions
will prevail overnight and Monday as moisture around the 700mb
level improves during the Day on Monday. Late day instability and
forcing across north central Kansas may also give rise to some
scattered evening convection but given the scatters nature of the
storms late Monday will not include mention of thunderstorms yet
in the Hays 06z tafs.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 98 69 96 69 / 20 20 30 30
GCK 98 67 94 67 / 20 30 40 40
EHA 96 67 93 67 / 20 20 40 30
LBL 98 69 96 69 / 20 20 30 30
HYS 98 68 94 68 / 30 70 50 50
P28 100 73 99 74 / 10 20 20 20
&&
.DDC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...Burgert
LONG TERM...Hovorka_42
AVIATION...Burgert
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
159 AM CDT Mon Aug 25 2014
...Updated short term discussion...
.SHORT TERM...(Today and tonight)
ISSUED AT 155 AM CDT MON AUG 25 2014
A wedge of warm 850mb to 700mb temperatures that was located just
south of a surface boundary which extended from the Oklahoma
panhandle to northeast Kansas at 00z Monday will lift north today
and by 00z Tuesday this warm air will be located across most of
western and south central Kansas. Based on the the forecast mixing
height and the 00z Tuesday temperatures in the 850mb to 700mb
level from the NAM and GFS it will be another day with highs in
the upper 90s to near 100 degrees across most of western and south
central Kansas.
In addition to the warming temperatures 700mb moisture will also
be improving across central and north central Kansas which may
give rise to some afternoon convection as CAPE values increase to
1000 to 2000 j/kg, especially across northern Kansas. At this time
it appears the better forcing and instability late today along
with the better low level moisture will be near/north the surface
boundary in north central Kansas so will focus late day convection
around and north of the interstate 70 corridor with more widely
scattered storms being possible further south.
Tonight warm air advection and moisture advection improves near
the nose of a developing low level jet. This will be just north of
a surface boundary that will remain nearly stationary early
tonight across west central and north central Kansas. At the same
time an upper level trough is forecast to cross northwest Kansas.
As a result will increase the chances for convection across west
central and north central Kansas, especially north of where the
+12c to +14c 700mb temperature gradient is forecast to be located
by the NAM and GFS at 06z and 12z Tuesday. Preciptable water
values Monday night are forecast to range from 1.5 to 1.75 across
northern Kansas so some storms tonight may produce periods of
heavy rainfall. Also am unable to rule out the chance for some
storms becoming severe Monday evening north of the interstate 70
corridor base on 0-6km shear of 30 to 40 knots and CAPE values
ranging from 1500 to near 3000 j/kg at 00z Tuesday from the NAM
and GFS. Main hazard at this time appears to be quarter size hail
and wind gusts of 60 mph or greater.
.LONG TERM...(Monday night through Sunday)
ISSUED AT 305 PM CDT SUN AUG 24 2014
An upper level trough will move from Nevada and into the
Intermountain West on Wednesday, then into the Central Plains on
Thursday, and will be slow to exit the Central Plains by Saturday
afternoon. New model runs have this upper system slowing down its
progress and this will allow for thunderstorm chances Tuesday into
Saturday, with the best chances from Tuesday night into Thursday
with a cold front. The storms may linger near to east of Dodge City
on Saturday as the upper wave moves eastward. Severe storm chances
do not look all that favorable with fairly weak upper level wind
fields.
Daytime highs will be warm and in the mid to upper 90s ahead of the
front on Tuesday, then in the low to mid 90s on Wednesday, cooling
into the 80s for Thursday and Friday. Highs warm back up to around
90 for the Weekend. Overnight lows around 70 on Monday night and
Tuesday night cool into the 60s into the Weekend.
&&
.AVIATION...(For the 06Z TAFS through 06Z Monday night)
ISSUED AT 1205 AM CDT MON AUG 25 2014
A weak surface boundary will lift north across western Kansas
overnight. As this boundary moves into west central and north
central Kansas the surface winds will become south southeast at
around 10 knots by 12z Monday. Based on 03z verification from the
NAM and HRRR will stay close to these models on timing of the wind
shift overnight. Southerly winds will increase to around 15 knots
by the early afternoon. BUFR soundings indicating VRF conditions
will prevail overnight and Monday as moisture around the 700mb
level improves during the Day on Monday. Late day instability and
forcing across north central Kansas may also give rise to some
scattered evening convection but given the scatters nature of the
storms late Monday will not include mention of thunderstorms yet
in the Hays 06z tafs.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 98 69 96 69 / 20 20 30 30
GCK 98 67 94 67 / 20 30 30 40
EHA 96 67 93 66 / 10 20 40 30
LBL 98 69 95 68 / 10 20 30 30
HYS 98 68 94 69 / 20 70 40 40
P28 100 73 98 74 / 10 20 20 20
&&
.DDC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...Burgert
LONG TERM...Kruse
AVIATION...Burgert
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
1208 AM CDT Mon Aug 25 2014
...Updated synopsis and aviation discussion...
.SYNOPSIS...
ISSUED AT 1205 AM CDT MON AUG 25 2014
At 00z Monday a 500mb ridge axis extended from eastern Texas to
the western Great Lakes region. A 700mb to 500mb low was located
over western North Dakota with a +70 knot 300mb jet extending from
the base of this upper low near northeast Colorado to Minnesota.
Further west southwest another upper level trough was over eastern
Oregon/southwest Idaho and a +90 knot 300mb jet was located on the
west side of this system. Over the Central Plains the 700mb
temperatures at 00z Monday ranged from +9c at North Platte to +13c
at Amarillo. 850mb temperatures ranged from 21C at North Platte to
+28c at Amarillo. A weak surface frontal boundary extended from
the western Oklahoma panhandle to northeast Kansas. An area of mid
60s to around 70 degree surface dew points were located just north
of this surface boundary which stretched from north central Kansas
to southeast Nebraska. 850mb and 700mb moisture axis was located
from eastern Oklahoma to southeast Nebraska.
&&
.SHORT TERM...(This evening through Monday)
ISSUED AT 320 PM CDT SUN AUG 24 2014
A strong shortwave trough was ejecting northeastward into the
northern plains this afternoon. The associated cold front had pushed
into southwest Kansas and stalled out. A few thunderstorms can`t be
ruled out in south central Kansas this evening ahead of the cold
front. Some elevated shower activity may develop tonight along the
Interstate 70 corridor to the south of the upper level jet streak;
but most of the precipitation should stay farther north. The front
will slowly edge northward tonight and Monday as the next upper
level trough digs into Nevada. This will result in a resumption of
southerly winds at 5 to 10 kts late tonight across much of southwest
Kansas. Lows will be mainly in the 60s to lower 70s. By Monday
afternoon, thunderstorms will develop along the stalled out front
in northern Kansas where low level moisture will be converging.
Thunderstorms may also develop farther south into western Kansas
ahead of a weak dryline. The best chance of severe storms with
large hail will be well north of Interstate 70 where surface based
CAPE and vertical wind shear will be stronger. High temperatures
ought to be in the upper 90s to near 100F given mostly sunny skies
with south winds.
.LONG TERM...(Monday night through Sunday)
ISSUED AT 305 PM CDT SUN AUG 24 2014
An upper level trough will move from Nevada and into the
Intermountain West on Wednesday, then into the Central Plains on
Thursday, and will be slow to exit the Central Plains by Saturday
afternoon. New model runs have this upper system slowing down its
progress and this will allow for thunderstorm chances Tuesday into
Saturday, with the best chances from Tuesday night into Thursday
with a cold front. The storms may linger near to east of Dodge City
on Saturday as the upper wave moves eastward. Severe storm chances
do not look all that favorable with fairly weak upper level wind
fields.
Daytime highs will be warm and in the mid to upper 90s ahead of the
front on Tuesday, then in the low to mid 90s on Wednesday, cooling
into the 80s for Thursday and Friday. Highs warm back up to around
90 for the Weekend. Overnight lows around 70 on Monday night and
Tuesday night cool into the 60s into the Weekend.
&&
.AVIATION...(For the 06Z TAFS through 06Z Monday night)
ISSUED AT 1205 AM CDT MON AUG 25 2014
A weak surface boundary will lift north across western Kansas
overnight. As this boundary moves into west central and north
central Kansas the surface winds will become south southeast at
around 10 knots by 12z Monday. Based on 03z verification from the
NAM and HRRR will stay close to these models on timing of the wind
shift overnight. Southerly winds will increase to around 15 knots
by the early afternoon. BUFR soundings indicating VRF conditions
will prevail overnight and Monday as moisture around the 700mb
level improves during the Day on Monday. Late day instability and
forcing across north central Kansas may also give rise to some
scattered evening convection but given the scatters nature of the
storms late Monday will not include mention of thunderstorms yet
in the Hays 06z tafs.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 69 96 69 92 / 20 30 30 30
GCK 67 94 67 88 / 30 30 40 30
EHA 67 93 66 87 / 20 40 30 30
LBL 69 95 68 89 / 20 30 30 30
HYS 68 94 69 90 / 30 40 40 30
P28 73 98 74 95 / 10 20 20 20
&&
.DDC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...Burgert
SHORT TERM...Finch
LONG TERM...Kruse
AVIATION...Burgert
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
144 PM EDT MON AUG 25 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 535 AM EDT MON AUG 25 2014
WATER VAPOR IMAGERY AND RUC ANALYSIS SHOW A VIGOROUS LOOKING
SHORTWAVE LIFTING THRU ND INTO MANITOBA. ASSOCIATED SFC LOW WAS
MOVING INTO SE MANITOBA WITH COLD FRONT EXTENDING THRU FAR ERN MN.
AS EXPECTED...SCT TSTMS DEVELOPED AHEAD OF FRONT IN MN LATE
YESTERDAY AFTN/EVENING. STORMS THEN ORGANIZED INTO A LINE AND PUSHED
E INTO WI/UPPER MI. AS OF 09Z...SHRA/TSTMS EXTENDED FROM NCNTRL LAKE
SUPERIOR TO THE HURON MTNS AND CRYSTAL FALLS. CONVECTION HAS HELD
TOGETHER FOR MUCH OF THE NIGHT...AND IT HAS ONLY BEEN IN THE LAST HR
OR TWO THAT A NOTABLE DIMINISHING TREND HAS BEGUN. NSSL WRF RUN FROM
00Z/24 AUG DID A GREAT JOB AND BETTER THAN ANY OTHER MODEL IN
CAPTURING WHAT OCCURRED LAST NIGHT INTO EARLY THIS MORNING...
INCLUDING THE DIMINISHING TREND NOW UNDERWAY.
WHILE THERE IS STILL SOME INCREASE IN INSTABILITY AHEAD OF
CONVECTION PER SPC MESOANALYSIS OF 3HR ML/MUCAPE CHANGE...OVERALL
MAGNITUDE OF INSTABILITY IS NOTABLY LESS THAN WHAT WAS SUPPORTING
THE CONVECTION EARLIER IN THE NIGHT. DIMINISHING INSTABILITY
COMBINED WITH WEAKENING LOW-LEVEL JET WILL CONTINUE TO CAUSE
SHRA/TSRA TO WEAKEN AS THEY PUSH E THIS MORNING. QUESTION THEN
BECOMES WHETHER THERE WILL BE REDEVELOPMENT ALONG THE MOISTURE AXIS
THAT WILL BE SLOWING DOWN. NSSL WRF INCLUDING THE NCEP ARW/NMM WHICH
ALSO DID WELL WITH CONVECTION LAST NIGHT SUGGEST LITTLE OR NO
ADDITIONAL DEVELOPMENT THIS AFTN. WILL BASICALLY FOLLOW THAT
SCENARIO GIVEN A LACK OF MUCH FORCING THIS AFTN. WITH INCREASING
SUNSHINE AND 850MB THERMAL RIDGE OVER THE AREA...TODAY SHOULD BE THE
WARMEST DAY OF THE WEEK. FCST SOUNDINGS SUPPORT MAX TEMPS AS HIGH AS
THE MID/UPPER 80S OVER ROUGHLY THE W HALF. COULD BE WARMER DEPENDING
ON HOW QUICKLY CLOUDS SCATTER OUT. E WILL BE COOLER WITH MORE CLOUD
COVER AND CONTINUED SOUTHERLY FLOW OFF LAKE MICHIGAN.
LOOKS LIKE A SECONDARY COLD FRONT/TROF WILL SWEEP ACROSS THE AREA
LATER THIS AFTN/EVENING. AS THE TROF MOVES INTO THE ERN FCST AREA
THIS EVENING WHERE MOISTURE/INSTABILITY LINGER...ISOLD SHRA AND
PERHAPS A TSRA MAY DEVELOP FROM ERN LAKE SUPERIOR INTO ERN UPPER MI.
OTHERWISE...EXPECT A DRY NIGHT...BECOMING COOLER AND LESS HUMID.
.LONG TERM...(TUESDAY THROUGH SUNDAY)
ISSUED AT 403 AM EDT MON AUG 25 2014
A FAIRLY QUIET AND GENERALLY DRY LONG TERM PERIOD IS IN STORE FOR
THE UPPER GREAT LAKES REGION FOR TUESDAY THROUGH THE WEEKEND. THIS
TRANSITION WILL OCCUR AS A RESULT OF THE LOW PRESSURE SYSTEM MOVING
THROUGH NORTHERN ONTARIO TODAY AND THE ASSOCIATED COLD FRONT THAT
PASSES THROUGH. BEHIND THIS LOW AND ASSOCIATED SHORTWAVE...HIGH
PRESSURE FROM THE EASTERN DAKOTAS WILL SHIFT EAST OVER THE UPPER
GREAT LAKES REGION BY WEDNESDAY WHILE A WEAK UPPER TROUGH SWEEPS
THROUGH. IN GENERAL...EXPECT THIS HIGH PRESSURE RIDGE TO SUPPRESS
ANY PRECIPITATION TO THE SOUTH OF THE AREA THROUGH THURSDAY. THERE
ARE A COUPLE MINOR ITEMS TO NOTE. FIRST...THE SECONDARY SHORTWAVE
MOVING THROUGH THE FLOW LATE TUESDAY NIGHT INTO WEDNESDAY MORNING
COULD TRY TO SPARK AN ISOLATED SHOWER BUT FEEL THE DRY AIR IN THE
LOWER LEVELS ASSOCIATED WITH THE HIGH PRESSURE RIDGE WILL INHIBIT
ANY RAIN FROM REACHING THE SURFACE. THUS...WILL JUST SHOW PASSING
MID CLOUDS AS THAT WAVE MOVES THROUGH. THE OTHER ITEM IS THE MUCH
COOLER AIR BELOW 850MB THAT WILL BE SURGING INTO THE CWA LATE
TONIGHT INTO TUESDAY. THIS WILL SETUP A RETURN TO ANOTHER COOLER
PERIOD OF HIGH TEMPERATURES OVER THE CWA. WITH THE COLD AIR JUST
STARTING TO MOVE IN ON TUESDAY...HIGHS OVER THE CENTRAL/EAST WILL
STILL RISE INTO THE UPPER 60S AND LOWER 70S WHILE AREAS OVER THE
WEST NEAR LAKE SUPERIOR WILL STAY IN THE MID 60S WITH THE
GUSTY WESTERLY WIND OFF THE LAKE. WEDNESDAY WILL BE THE COOLEST DAY
(AIDED BY THE MORNING MID CLOUDS LIMITING HEATING AND MODEL AVERAGE
850MB TEMPS AROUND 6-7C)...WITH HIGHS IN THE 60S OVER MOST OF THE
CWA. 850MB TEMPS WILL REBOUND SLIGHTLY ON THURSDAY AND ALLOW HIGHS
TO BE IN THE UPPER 60S TO AROUND 70 DEGREES. ALONG WITH THAT COOLER
AIR ON TUESDAY MORNING...SOME OF THE MODELS ARE INDICATING ENOUGH
MOISTURE FOR SOME CLOUDS OVER THE NORTH HALF OF THE CWA. THINK THE
COVERAGE WILL BE THE GREATEST DURING THE AFTERNOON HOURS WHEN THE
DIURNAL HEATING IS MAXIMIZED AND WILL SHOW PARTLY CLOUDY SKIES
DURING THAT TIME. EXPECT MOSTLY CLEAR SKIES FOR THE REST OF THE
MIDDLE OF THE WORK WEEK.
THE FOCUS THURSDAY NIGHT INTO THE WEEKEND WILL BE THE UPPER
DISTURBANCE MOVING OUT OF THE CENTRAL ROCKIES AND INTO THE CENTRAL
PLAINS ON WEDNESDAY. THE INITIAL PORTION OF THIS WAVE WILL SHIFT
NORTHEAST TOWARDS THE UPPER GREAT LAKES REGION THURSDAY NIGHT AND
FRIDAY...WITH MODELS STILL VARYING ON THE NORTHWARD EXTENT OF THE
WAVE AND ASSOCIATED PRECIP. CURRENT CONSENSUS IS FOR IT TO BRUSH
THE SOUTHEAST THIRD OF THE CWA AND WILL SHOW SLIGHT CHANCES IN THAT
AREA. THE SECOND WAVE WILL PUSH THROUGH THE AREA FRIDAY NIGHT INTO
SATURDAY AND BRING ANOTHER OPPORTUNITY FOR PRECIPITATION. MODELS
ALSO VARYING ON THE LOCATION THIS WAVE...SO WILL FOLLOW A BLEND OF
GEM/GFS/ECMWF FOR POPS (SLIGHT OR LOW END CHANCES) WITH THE BEST
CHANCES OVER THE SOUTHEAST.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON)
ISSUED AT 139 PM EDT MON AUG 25 2014
VFR CONDITIONS WILL BE THE RULE THROUGH THE FCST PERIOD.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 535 AM EDT MON AUG 25 2014
FOG MAY BE AN ISSUE OVER PORTIONS OF LAKE SUPERIOR THRU THIS
EVENING...MAINLY CNTRL/E AND ESPECIALLY NE GIVEN THE HUMID AIR MASS
AND PCPN THAT HAS OCCURRED. PASSAGE OF COLD FRONT AND ARRIVAL OF
DRIER AIR TODAY/THIS EVENING WILL THEN WORK TO CLEAR OUT THE FOG
FROM W TO E. BEHIND FRONT...WESTERLY WINDS WILL INCREASE TO
15-25KT OVER WRN LAKE SUPERIOR THIS AFTN AND THEN OVER CNTRL LAKE
SUPERIOR THIS EVENING. THESE STRONGER WINDS WILL LINGER INTO TUE
MORNING...THEN WINDS WILL DIMINISH AS HIGH PRES MOVES CLOSER TO THE
AREA. THE HIGH WILL SETTLE INTO THE UPPER LAKES TUE NIGHT THRU
THU...BRINGING A PERIOD OF LIGHTER WINDS MOSTLY UNDER 15KT. THE
LIGHTER WINDS WILL LINGER INTO FRI DESPITE THE HIGH MOVING TO THE E.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...ROLFSON
LONG TERM...SRF
AVIATION...TITUS
MARINE...ROLFSON
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
745 AM EDT MON AUG 25 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 535 AM EDT MON AUG 25 2014
WATER VAPOR IMAGERY AND RUC ANALYSIS SHOW A VIGOROUS LOOKING
SHORTWAVE LIFTING THRU ND INTO MANITOBA. ASSOCIATED SFC LOW WAS
MOVING INTO SE MANITOBA WITH COLD FRONT EXTENDING THRU FAR ERN MN.
AS EXPECTED...SCT TSTMS DEVELOPED AHEAD OF FRONT IN MN LATE
YESTERDAY AFTN/EVENING. STORMS THEN ORGANIZED INTO A LINE AND PUSHED
E INTO WI/UPPER MI. AS OF 09Z...SHRA/TSTMS EXTENDED FROM NCNTRL LAKE
SUPERIOR TO THE HURON MTNS AND CRYSTAL FALLS. CONVECTION HAS HELD
TOGETHER FOR MUCH OF THE NIGHT...AND IT HAS ONLY BEEN IN THE LAST HR
OR TWO THAT A NOTABLE DIMINISHING TREND HAS BEGUN. NSSL WRF RUN FROM
00Z/24 AUG DID A GREAT JOB AND BETTER THAN ANY OTHER MODEL IN
CAPTURING WHAT OCCURRED LAST NIGHT INTO EARLY THIS MORNING...
INCLUDING THE DIMINISHING TREND NOW UNDERWAY.
WHILE THERE IS STILL SOME INCREASE IN INSTABILITY AHEAD OF
CONVECTION PER SPC MESOANALYSIS OF 3HR ML/MUCAPE CHANGE...OVERALL
MAGNITUDE OF INSTABILITY IS NOTABLY LESS THAN WHAT WAS SUPPORTING
THE CONVECTION EARLIER IN THE NIGHT. DIMINISHING INSTABILITY
COMBINED WITH WEAKENING LOW-LEVEL JET WILL CONTINUE TO CAUSE
SHRA/TSRA TO WEAKEN AS THEY PUSH E THIS MORNING. QUESTION THEN
BECOMES WHETHER THERE WILL BE REDEVELOPMENT ALONG THE MOISTURE AXIS
THAT WILL BE SLOWING DOWN. NSSL WRF INCLUDING THE NCEP ARW/NMM WHICH
ALSO DID WELL WITH CONVECTION LAST NIGHT SUGGEST LITTLE OR NO
ADDITIONAL DEVELOPMENT THIS AFTN. WILL BASICALLY FOLLOW THAT
SCENARIO GIVEN A LACK OF MUCH FORCING THIS AFTN. WITH INCREASING
SUNSHINE AND 850MB THERMAL RIDGE OVER THE AREA...TODAY SHOULD BE THE
WARMEST DAY OF THE WEEK. FCST SOUNDINGS SUPPORT MAX TEMPS AS HIGH AS
THE MID/UPPER 80S OVER ROUGHLY THE W HALF. COULD BE WARMER DEPENDING
ON HOW QUICKLY CLOUDS SCATTER OUT. E WILL BE COOLER WITH MORE CLOUD
COVER AND CONTINUED SOUTHERLY FLOW OFF LAKE MICHIGAN.
LOOKS LIKE A SECONDARY COLD FRONT/TROF WILL SWEEP ACROSS THE AREA
LATER THIS AFTN/EVENING. AS THE TROF MOVES INTO THE ERN FCST AREA
THIS EVENING WHERE MOISTURE/INSTABILITY LINGER...ISOLD SHRA AND
PERHAPS A TSRA MAY DEVELOP FROM ERN LAKE SUPERIOR INTO ERN UPPER MI.
OTHERWISE...EXPECT A DRY NIGHT...BECOMING COOLER AND LESS HUMID.
.LONG TERM...(TUESDAY THROUGH SUNDAY)
ISSUED AT 403 AM EDT MON AUG 25 2014
A FAIRLY QUIET AND GENERALLY DRY LONG TERM PERIOD IS IN STORE FOR
THE UPPER GREAT LAKES REGION FOR TUESDAY THROUGH THE WEEKEND. THIS
TRANSITION WILL OCCUR AS A RESULT OF THE LOW PRESSURE SYSTEM MOVING
THROUGH NORTHERN ONTARIO TODAY AND THE ASSOCIATED COLD FRONT THAT
PASSES THROUGH. BEHIND THIS LOW AND ASSOCIATED SHORTWAVE...HIGH
PRESSURE FROM THE EASTERN DAKOTAS WILL SHIFT EAST OVER THE UPPER
GREAT LAKES REGION BY WEDNESDAY WHILE A WEAK UPPER TROUGH SWEEPS
THROUGH. IN GENERAL...EXPECT THIS HIGH PRESSURE RIDGE TO SUPPRESS
ANY PRECIPITATION TO THE SOUTH OF THE AREA THROUGH THURSDAY. THERE
ARE A COUPLE MINOR ITEMS TO NOTE. FIRST...THE SECONDARY SHORTWAVE
MOVING THROUGH THE FLOW LATE TUESDAY NIGHT INTO WEDNESDAY MORNING
COULD TRY TO SPARK AN ISOLATED SHOWER BUT FEEL THE DRY AIR IN THE
LOWER LEVELS ASSOCIATED WITH THE HIGH PRESSURE RIDGE WILL INHIBIT
ANY RAIN FROM REACHING THE SURFACE. THUS...WILL JUST SHOW PASSING
MID CLOUDS AS THAT WAVE MOVES THROUGH. THE OTHER ITEM IS THE MUCH
COOLER AIR BELOW 850MB THAT WILL BE SURGING INTO THE CWA LATE
TONIGHT INTO TUESDAY. THIS WILL SETUP A RETURN TO ANOTHER COOLER
PERIOD OF HIGH TEMPERATURES OVER THE CWA. WITH THE COLD AIR JUST
STARTING TO MOVE IN ON TUESDAY...HIGHS OVER THE CENTRAL/EAST WILL
STILL RISE INTO THE UPPER 60S AND LOWER 70S WHILE AREAS OVER THE
WEST NEAR LAKE SUPERIOR WILL STAY IN THE MID 60S WITH THE
GUSTY WESTERLY WIND OFF THE LAKE. WEDNESDAY WILL BE THE COOLEST DAY
(AIDED BY THE MORNING MID CLOUDS LIMITING HEATING AND MODEL AVERAGE
850MB TEMPS AROUND 6-7C)...WITH HIGHS IN THE 60S OVER MOST OF THE
CWA. 850MB TEMPS WILL REBOUND SLIGHTLY ON THURSDAY AND ALLOW HIGHS
TO BE IN THE UPPER 60S TO AROUND 70 DEGREES. ALONG WITH THAT COOLER
AIR ON TUESDAY MORNING...SOME OF THE MODELS ARE INDICATING ENOUGH
MOISTURE FOR SOME CLOUDS OVER THE NORTH HALF OF THE CWA. THINK THE
COVERAGE WILL BE THE GREATEST DURING THE AFTERNOON HOURS WHEN THE
DIURNAL HEATING IS MAXIMIZED AND WILL SHOW PARTLY CLOUDY SKIES
DURING THAT TIME. EXPECT MOSTLY CLEAR SKIES FOR THE REST OF THE
MIDDLE OF THE WORK WEEK.
THE FOCUS THURSDAY NIGHT INTO THE WEEKEND WILL BE THE UPPER
DISTURBANCE MOVING OUT OF THE CENTRAL ROCKIES AND INTO THE CENTRAL
PLAINS ON WEDNESDAY. THE INITIAL PORTION OF THIS WAVE WILL SHIFT
NORTHEAST TOWARDS THE UPPER GREAT LAKES REGION THURSDAY NIGHT AND
FRIDAY...WITH MODELS STILL VARYING ON THE NORTHWARD EXTENT OF THE
WAVE AND ASSOCIATED PRECIP. CURRENT CONSENSUS IS FOR IT TO BRUSH
THE SOUTHEAST THIRD OF THE CWA AND WILL SHOW SLIGHT CHANCES IN THAT
AREA. THE SECOND WAVE WILL PUSH THROUGH THE AREA FRIDAY NIGHT INTO
SATURDAY AND BRING ANOTHER OPPORTUNITY FOR PRECIPITATION. MODELS
ALSO VARYING ON THE LOCATION THIS WAVE...SO WILL FOLLOW A BLEND OF
GEM/GFS/ECMWF FOR POPS (SLIGHT OR LOW END CHANCES) WITH THE BEST
CHANCES OVER THE SOUTHEAST.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z TUESDAY MORNING)
ISSUED AT 745 AM EDT MON AUG 25 2014
AREA OF SHRA HAS MOVED E OF KIWD/KCMX. BEHIND THE SHRA...KIWD SHOULD
CONTINUE TO SEE VFR CONDITIONS. AT KCMX...IFR CIGS HAVE RECENTLY
ARRIVED. EXPECT THIS TO BE SHORT LIVED WITH A RETURN TO VFR BY MID
OR LATE MORNING. VFR CONDITIONS WILL THEN CONTINUE AT KIWD/KCMX FOR
THE REMAINDER OF THE FCST PERIOD AS DRIER AIR FLOWS INTO THE AREA
BEHIND A COLD FRONT. AT KSAW...-SHRA WILL END IN THE NEXT FEW HRS.
BASED ON OBS AROUND THE AREA...VFR CONDITONS WILL LIKELY PREVAIL...
BUT THERE MAY BE OCNL MVFR CIGS. VFR CONDITIONS WILL THEN BE THE
RULE FOR REMAINDER OF THE FCST PERIOD.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 535 AM EDT MON AUG 25 2014
FOG MAY BE AN ISSUE OVER PORTIONS OF LAKE SUPERIOR THRU THIS
EVENING...MAINLY CNTRL/E AND ESPECIALLY NE GIVEN THE HUMID AIR MASS
AND PCPN THAT HAS OCCURRED. PASSAGE OF COLD FRONT AND ARRIVAL OF
DRIER AIR TODAY/THIS EVENING WILL THEN WORK TO CLEAR OUT THE FOG
FROM W TO E. BEHIND FRONT...WESTERLY WINDS WILL INCREASE TO
15-25KT OVER WRN LAKE SUPERIOR THIS AFTN AND THEN OVER CNTRL LAKE
SUPERIOR THIS EVENING. THESE STRONGER WINDS WILL LINGER INTO TUE
MORNING...THEN WINDS WILL DIMINISH AS HIGH PRES MOVES CLOSER TO THE
AREA. THE HIGH WILL SETTLE INTO THE UPPER LAKES TUE NIGHT THRU
THU...BRINGING A PERIOD OF LIGHTER WINDS MOSTLY UNDER 15KT. THE
LIGHTER WINDS WILL LINGER INTO FRI DESPITE THE HIGH MOVING TO THE E.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...ROLFSON
LONG TERM...SRF
AVIATION...ROLFSON
MARINE...ROLFSON
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
536 AM EDT MON AUG 25 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 535 AM EDT MON AUG 25 2014
WATER VAPOR IMAGERY AND RUC ANALYSIS SHOW A VIGOROUS LOOKING
SHORTWAVE LIFTING THRU ND INTO MANITOBA. ASSOCIATED SFC LOW WAS
MOVING INTO SE MANITOBA WITH COLD FRONT EXTENDING THRU FAR ERN MN.
AS EXPECTED...SCT TSTMS DEVELOPED AHEAD OF FRONT IN MN LATE
YESTERDAY AFTN/EVENING. STORMS THEN ORGANIZED INTO A LINE AND PUSHED
E INTO WI/UPPER MI. AS OF 09Z...SHRA/TSTMS EXTENDED FROM NCNTRL LAKE
SUPERIOR TO THE HURON MTNS AND CRYSTAL FALLS. CONVECTION HAS HELD
TOGETHER FOR MUCH OF THE NIGHT...AND IT HAS ONLY BEEN IN THE LAST HR
OR TWO THAT A NOTABLE DIMINISHING TREND HAS BEGUN. NSSL WRF RUN FROM
00Z/24 AUG DID A GREAT JOB AND BETTER THAN ANY OTHER MODEL IN
CAPTURING WHAT OCCURRED LAST NIGHT INTO EARLY THIS MORNING...
INCLUDING THE DIMINISHING TREND NOW UNDERWAY.
WHILE THERE IS STILL SOME INCREASE IN INSTABILITY AHEAD OF
CONVECTION PER SPC MESOANALYSIS OF 3HR ML/MUCAPE CHANGE...OVERALL
MAGNITUDE OF INSTABILITY IS NOTABLY LESS THAN WHAT WAS SUPPORTING
THE CONVECTION EARLIER IN THE NIGHT. DIMINISHING INSTABILITY
COMBINED WITH WEAKENING LOW-LEVEL JET WILL CONTINUE TO CAUSE
SHRA/TSRA TO WEAKEN AS THEY PUSH E THIS MORNING. QUESTION THEN
BECOMES WHETHER THERE WILL BE REDEVELOPMENT ALONG THE MOISTURE AXIS
THAT WILL BE SLOWING DOWN. NSSL WRF INCLUDING THE NCEP ARW/NMM WHICH
ALSO DID WELL WITH CONVECTION LAST NIGHT SUGGEST LITTLE OR NO
ADDITIONAL DEVELOPMENT THIS AFTN. WILL BASICALLY FOLLOW THAT
SCENARIO GIVEN A LACK OF MUCH FORCING THIS AFTN. WITH INCREASING
SUNSHINE AND 850MB THERMAL RIDGE OVER THE AREA...TODAY SHOULD BE THE
WARMEST DAY OF THE WEEK. FCST SOUNDINGS SUPPORT MAX TEMPS AS HIGH AS
THE MID/UPPER 80S OVER ROUGHLY THE W HALF. COULD BE WARMER DEPENDING
ON HOW QUICKLY CLOUDS SCATTER OUT. E WILL BE COOLER WITH MORE CLOUD
COVER AND CONTINUED SOUTHERLY FLOW OFF LAKE MICHIGAN.
LOOKS LIKE A SECONDARY COLD FRONT/TROF WILL SWEEP ACROSS THE AREA
LATER THIS AFTN/EVENING. AS THE TROF MOVES INTO THE ERN FCST AREA
THIS EVENING WHERE MOISTURE/INSTABILITY LINGER...ISOLD SHRA AND
PERHAPS A TSRA MAY DEVELOP FROM ERN LAKE SUPERIOR INTO ERN UPPER MI.
OTHERWISE...EXPECT A DRY NIGHT...BECOMING COOLER AND LESS HUMID.
.LONG TERM...(TUESDAY THROUGH SUNDAY)
ISSUED AT 403 AM EDT MON AUG 25 2014
A FAIRLY QUIET AND GENERALLY DRY LONG TERM PERIOD IS IN STORE FOR
THE UPPER GREAT LAKES REGION FOR TUESDAY THROUGH THE WEEKEND. THIS
TRANSITION WILL OCCUR AS A RESULT OF THE LOW PRESSURE SYSTEM MOVING
THROUGH NORTHERN ONTARIO TODAY AND THE ASSOCIATED COLD FRONT THAT
PASSES THROUGH. BEHIND THIS LOW AND ASSOCIATED SHORTWAVE...HIGH
PRESSURE FROM THE EASTERN DAKOTAS WILL SHIFT EAST OVER THE UPPER
GREAT LAKES REGION BY WEDNESDAY WHILE A WEAK UPPER TROUGH SWEEPS
THROUGH. IN GENERAL...EXPECT THIS HIGH PRESSURE RIDGE TO SUPPRESS
ANY PRECIPITATION TO THE SOUTH OF THE AREA THROUGH THURSDAY. THERE
ARE A COUPLE MINOR ITEMS TO NOTE. FIRST...THE SECONDARY SHORTWAVE
MOVING THROUGH THE FLOW LATE TUESDAY NIGHT INTO WEDNESDAY MORNING
COULD TRY TO SPARK AN ISOLATED SHOWER BUT FEEL THE DRY AIR IN THE
LOWER LEVELS ASSOCIATED WITH THE HIGH PRESSURE RIDGE WILL INHIBIT
ANY RAIN FROM REACHING THE SURFACE. THUS...WILL JUST SHOW PASSING
MID CLOUDS AS THAT WAVE MOVES THROUGH. THE OTHER ITEM IS THE MUCH
COOLER AIR BELOW 850MB THAT WILL BE SURGING INTO THE CWA LATE
TONIGHT INTO TUESDAY. THIS WILL SETUP A RETURN TO ANOTHER COOLER
PERIOD OF HIGH TEMPERATURES OVER THE CWA. WITH THE COLD AIR JUST
STARTING TO MOVE IN ON TUESDAY...HIGHS OVER THE CENTRAL/EAST WILL
STILL RISE INTO THE UPPER 60S AND LOWER 70S WHILE AREAS OVER THE
WEST NEAR LAKE SUPERIOR WILL STAY IN THE MID 60S WITH THE
GUSTY WESTERLY WIND OFF THE LAKE. WEDNESDAY WILL BE THE COOLEST DAY
(AIDED BY THE MORNING MID CLOUDS LIMITING HEATING AND MODEL AVERAGE
850MB TEMPS AROUND 6-7C)...WITH HIGHS IN THE 60S OVER MOST OF THE
CWA. 850MB TEMPS WILL REBOUND SLIGHTLY ON THURSDAY AND ALLOW HIGHS
TO BE IN THE UPPER 60S TO AROUND 70 DEGREES. ALONG WITH THAT COOLER
AIR ON TUESDAY MORNING...SOME OF THE MODELS ARE INDICATING ENOUGH
MOISTURE FOR SOME CLOUDS OVER THE NORTH HALF OF THE CWA. THINK THE
COVERAGE WILL BE THE GREATEST DURING THE AFTERNOON HOURS WHEN THE
DIURNAL HEATING IS MAXIMIZED AND WILL SHOW PARTLY CLOUDY SKIES
DURING THAT TIME. EXPECT MOSTLY CLEAR SKIES FOR THE REST OF THE
MIDDLE OF THE WORK WEEK.
THE FOCUS THURSDAY NIGHT INTO THE WEEKEND WILL BE THE UPPER
DISTURBANCE MOVING OUT OF THE CENTRAL ROCKIES AND INTO THE CENTRAL
PLAINS ON WEDNESDAY. THE INITIAL PORTION OF THIS WAVE WILL SHIFT
NORTHEAST TOWARDS THE UPPER GREAT LAKES REGION THURSDAY NIGHT AND
FRIDAY...WITH MODELS STILL VARYING ON THE NORTHWARD EXTENT OF THE
WAVE AND ASSOCIATED PRECIP. CURRENT CONSENSUS IS FOR IT TO BRUSH
THE SOUTHEAST THIRD OF THE CWA AND WILL SHOW SLIGHT CHANCES IN THAT
AREA. THE SECOND WAVE WILL PUSH THROUGH THE AREA FRIDAY NIGHT INTO
SATURDAY AND BRING ANOTHER OPPORTUNITY FOR PRECIPITATION. MODELS
ALSO VARYING ON THE LOCATION THIS WAVE...SO WILL FOLLOW A BLEND OF
GEM/GFS/ECMWF FOR POPS (SLIGHT OR LOW END CHANCES) WITH THE BEST
CHANCES OVER THE SOUTHEAST.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT)
ISSUED AT 140 AM EDT MON AUG 25 2014
AN APPROACHING COLD FRONT OVERNIGHT WILL BRING SCT/NMRS SHRA/TSRA
INTO UPPER MI. THE BEST CHANCE FOR TSRA WILL BE ACROSS THE WEST AT
IWD/CMX WHILE FARTHER EAST AT SAW...LESS FAVORABLE INSTABILITY WILL
LIMIT TS CHANCES. PLENTY OF MOISTURE WILL REMAIN WITH UPSLOPE
CONDITIONS BRINGING ANOTHER ROUND OF MAINLY MVFR CEILINGS TO SAW LATE
IN THE NIGHT THAT SHOULD DROP TO IFR TOWARD SUNRISE. OTHERWISE...
LOOK FOR SLOWLY IMPROVING CONDITIONS W TO E TODAY AS DRIER AIR WORKS
IN FROM THE W BEHIND THE EXITING COLD FRONT.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 535 AM EDT MON AUG 25 2014
FOG MAY BE AN ISSUE OVER PORTIONS OF LAKE SUPERIOR THRU THIS
EVENING...MAINLY CNTRL/E AND ESPECIALLY NE GIVEN THE HUMID AIR MASS
AND PCPN THAT HAS OCCURRED. PASSAGE OF COLD FRONT AND ARRIVAL OF
DRIER AIR TODAY/THIS EVENING WILL THEN WORK TO CLEAR OUT THE FOG
FROM W TO E. BEHIND FRONT...WESTERLY WINDS WILL INCREASE TO
15-25KT OVER WRN LAKE SUPERIOR THIS AFTN AND THEN OVER CNTRL LAKE
SUPERIOR THIS EVENING. THESE STRONGER WINDS WILL LINGER INTO TUE
MORNING...THEN WINDS WILL DIMINISH AS HIGH PRES MOVES CLOSER TO THE
AREA. THE HIGH WILL SETTLE INTO THE UPPER LAKES TUE NIGHT THRU
THU...BRINGING A PERIOD OF LIGHTER WINDS MOSTLY UNDER 15KT. THE
LIGHTER WINDS WILL LINGER INTO FRI DESPITE THE HIGH MOVING TO THE E.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...ROLFSON
LONG TERM...SRF
AVIATION...JLB
MARINE...ROLFSON
AREA FORECAST DISCUSSION
NWS GRAND RAPIDS MI
325 AM EDT MON AUG 25 2014
LATEST UPDATE...
SYNOPSIS/SHORT TERM/LONG TERM/MARINE
.SYNOPSIS...
ISSUED AT 325 AM EDT MON AUG 25 2014
WARM AND HUMID CONDITIONS WILL CONTINUE TODAY THROUGH TUESDAY WITH
SCATTERED SHOWERS AND THUNDERSTORMS. THUNDERSTORMS THIS AFTERNOON
THROUGH TUESDAY MAY CONTAIN LOCALLY HEAVY RAINFALL. DRY AND COOLER
WEATHER WILL BRIEFLY RETURN WEDNESDAY FOLLOWED BY WARMER AND MORE
HUMID WEATHER WITH ANOTHER CHANCE OF SHOWERS AND STORMS LATE IN
THE WEEK.
&&
.SHORT TERM...(TODAY THROUGH WEDNESDAY)
ISSUED AT 325 AM EDT MON AUG 25 2014
IT WILL BE VERY WARM AND HUMID TODAY WITH MAX TEMPS REACHING WELL
INTO THE 80S AND DEW POINT VALUES UP INTO THE UPPER 60S TO LOWER
70S. SCATTERED SHOWERS AND THUNDERSTORMS WILL DEVELOP LATER TODAY
AS INSTABILITY BUILDS AND SB CAPE VALUES POTENTIALLY REACH AROUND
2000-2500 J/KG NEAR TO EAST OF US-131 THIS AFTERNOON.
SEVERE WX IS UNLIKELY MAINLY DUE TO WEAK DEEP LAYER SHEAR BUT AN
ISOLATED SEVERE STORM CANNOT BE RULED OUT THIS AFTERNOON AND EARLY
EVENING WHEN INSTABILITY WILL BE MAXIMIZED. ANY STORMS THAT DO
DEVELOP COULD PRODUCE LOCALLY RAINFALL WITH PRECIPITABLE WATER
VALUES UP IN THE 1.75 TO 2 INCH RANGE TODAY.
SCATTERED SHOWERS AND PERHAPS A FEW STORMS WILL CONTINUE INTO THIS
EVENING. THEN THE COLD FRONT WILL BRING SCATTERED SHOWERS AND
THUNDERSTORMS ON TUESDAY. THE BEST CHANCE FOR A FEW STRONG TO
POTENTIALLY SEVERE STORMS TUESDAY WOULD BE IN THE AFTERNOON OVER OUR
SE FCST AREA WHEN SB CAPE VALUES WILL POTENTIALLY REACH AROUND 3000
J/KG.
IT HAS BEEN NOTED THAT OVERALL SHORT TO MEDIUM RANGE GUIDANCE
TRENDS ARE BRINGING THE COLD FRONT THROUGH FASTER. THEREFORE WE
HAVE TRIMMED BACK POPS SIGNIFICANTLY FOR TUESDAY NIGHT AND ARE
KEEPING LINGERING LOW POPS CONFINED TO OUR SOUTHERN FORECAST AREA.
DRY WEATHER IS NOW ANTICIPATED WEDNESDAY WITH THE HIGH PRESSURE RIDGE
IN PLACE OVER THE NORTHERN GREAT LAKES REGION.
.LONG TERM...(WEDNESDAY NIGHT THROUGH SUNDAY)
ISSUED AT 325 AM EDT MON AUG 25 2014
THE LAST COUPLE NIGHTS HAVE SEEN THE GFS GUIDANCE TREND TOWARDS THE
ECMWF IN TERMS OF THE EVOLUTION OF THE PATTERN. TONIGHT...HAVE
THEREFORE FOLLOWED THE LEAD OF THE ECMWF THROUGH THE LONG TERM
FORECAST.
THE LONG TERM LOOKS TO FEATURE A DECENT ABOUT OF RAINFALL WITH A
BOUNDARY OSCILLATING THROUGH THE REGION AND NEAR NORMAL TEMPERATURES.
AS FOR THE DETAILS...THE PERIOD LOOKS TO START OFF DRY WITH SURFACE
HIGH PRESSURE SAGGING INTO THE AREA FROM THE NORTH WEDNESDAY NIGHT.
FEEL THURSDAY WILL LIKELY BE DRY AS WELL...BUT BLENDED IN WITH
NEIGHBORING OFFICES AND HAVE A 20 PCT CHANCE FOR SHOWERS/STORMS IN
THE FAR WEST.
CHANCES FOR SHOWERS AND STORMS THEN LOOK TO BE POSSIBLE IN THE
REMAINDER OF THE FORECAST PERIOD...THURSDAY NIGHT THROUGH SUNDAY.
MOISTURE COMES SURGING BACK IN THURSDAY NIGHT ESPECIALLY ALOFT. THE
ECMWF HAS A WARM FRONT OR A STATIONARY BOUNDARY NEARBY FRI-SUN. HAVE
CHANCE POPS ESSENTIALLY BLANKETED THROUGHOUT THIS PERIOD OF THE
FORECAST. THE DAYS 4-5 AND 6-7 QPF PROGS FROM WPC ALSO BEAR THIS
OUT. THEY SHOW RAINFALL TOTALS AROUND AN INCH FOR MOST AREAS...WHICH
SEEMS REASONABLE.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT)
ISSUED AT 1120 PM EDT SUN AUG 24 2014
IT WOULD SEEM FOG IS BECOMING LESS LIKELY OVERNIGHT. AS I WROTE
FOR THE 00Z TAF SET...THE WINDS IN THE BOUNDARY LAYER OF BETWEEN
15 AND 25 KNOTS ARE ENOUGH TO KEEP SURFACE FOG FROM BECOMING MUCH
OF AN ISSUE TONIGHT. INSTEAD THE IR-FOG LOOP SHOWS PATCHY LOW CLOUDS
(MVFR CIGS) DEVELOPING NEAR AND SOUTH OF I-96. AS THE AIR
CONTINUES TO COOL OVERNIGHT THE LOW CLOUDS SHOULD BECOME MORE
EXTENSIVE AND CIGS SHOULD LOWER SOME. SO I HAVE ONLY MVFR CIGS/VSBY
AT ALL TAF SITES.
THE CONVECTION FOR MONDAY STILL SEEMS POSSIBLE. THE LATEST VERSION
OF THE RAP MODEL AND THE NAM12 SHOW LATE MORNING AND AFTERNOON
CONVECTION. SO...I NOW HAVE VCTS AFTER 15Z FOR THAT. I WOULD
EXPECT ONCE THE SUN SETS MONDAY EVENING THE CONVECTION WILL BE
DONE. THERE SHOULD BE ENOUGH WIND TOMORROW NIGHT TO KEEP FOG FROM
BECOMING AN ISSUE.
&&
.MARINE...
ISSUED AT 325 AM EDT MON AUG 25 2014
MINIMAL WIND AND WAVE ACTION IS ANTICIPATED TODAY THROUGH TONIGHT
INTO TUESDAY. HOWEVER PATCHY FOG WILL POSE A HAZARD TO MARINERS.
&&
.HYDROLOGY...
ISSUED AT 1104 AM EDT SUN AUG 24 2014
BEST CHANCE FOR SIGNIFICANT RAINFALL WOULD BE MONDAY NIGHT THROUGH
WEDNESDAY WITH A SLOW MOVING COLD FRONT. THIS IS NOT A GUARANTEE
AS THE LLJ IS FORECAST TO BE QUITE WEAK. NEVERTHELESS...A VERY
MOIST ATMOSPHERE COMBINED WITH FORCING VIA THE COLD FRONT AND SLOW
CELL MOVEMENT COULD RESULT IN SOME SIGNIFICANT RAINFALL IF STORMS
DEVELOP OVER OUR AREA. PW VALUES WILL LIKELY BE AROUND 1.75"
MONDAY NIGHT AND TUESDAY. MODEL GUIDANCE IS MIXED REGARDING HOW
LONG THE FRONT MAY HANG UP...SO IT IS UNCLEAR WHEN THE THREAT FOR
SIGNIFICANT RAINFALL WOULD END.
&&
.GRR WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LM...NONE.
&&
$$
SYNOPSIS...LAURENS
SHORT TERM...LAURENS
LONG TERM...DUKE
AVIATION...WDM
HYDROLOGY...HOVING
MARINE...LAURENS
AREA FORECAST DISCUSSION...UPDATED AVIATION
NWS ST LOUIS MO
607 PM CDT Tue Aug 26 2014
.SHORT TERM: (Through Late Tonight)
Issued at 324 PM CDT Tue Aug 26 2014
A fairly well-defined convergence zone extends along an axis from
Champaign through St. Louis towards Springfield this afternoon
associated with an old convective boundary. SBCAPE is over 4000
j/kg with little CIN along this corridor, and scattered storms
were noted along portions of the boundary. Short range HRRR and
RAP guidance suggests some of this activity may linger past sunset
and thus have included some low pops within the region. Otherwise the
other threat of showers and thunderstorms tonight will shift
northward along and north of the real east-west frontal boundary
which will be drapped across northern KS and northern MO into
central IL, mainly late tonight.
Glass
.LONG TERM: (Wednesday through Next Tuesday)
Issued at 324 PM CDT Tue Aug 26 2014
The east-west frontal boundary will gradually sink southward
throughout the day Wednesday settling into southern MO and
southern IL by early evening. Very unstable conditions due to
daytime heating and high dew points will persist and maintain a
threat of scattered showers and thunderstorms will the front, and
just to its north. Present indications are that overall the
atmosphere will be slightly cooler in the low-mid levels. This
cooling along with the front and attendant clouds/precipitation
are expected to diminish the magnitude of the recent heat. However
despite slightly cooler temperatures, the pooling of surface dew
points in the 70s will continue to produce afternoon heat index
values of 100-105 degrees along and south of a Columbia to
Litchfield line. I have extended the heat advisories and warnings
in this region, while the excessive heat appears to be over across
northern MO and central IL where cooler conditions have also been
noted today.
The east-west front is expected to retreat back northward on
Thursday as an upper trof migrates out of the Rockies and the
associated surface low lifts northeastward. The highest pops will
remain along and north of the retreating boundary, primarily
northern sections of the CWA Thursday-Thursday night. Heat is a tough
call on Thursday and the current forecast calls for highs in the
upper 80s to lower 90s. There could potentially be some lingering
pockets of afternoon HI values of 100+ but there is too much
uncertainty to extend any heat headlines to this time period.
The heat should definitely come to an end by the weekend. The models
move the upper trof from the Plains on Friday into and through the
MS Valley by late Sunday. A good chance of showers and thunderstorms
will accompany this trof and the attendant frontal system, with
cooler temperatures closer to normal for this time of year.
Glass
&&
.AVIATION: (For the 00z TAFs through 00z Wednesday Evening)
Issued at 530 PM CDT Tue Aug 26 2014
Scattered thunderstorms in the St Louis metro area will impact
STL and possibly also SUS and CPS until 01Z or 02Z this evening.
These storms should dissipate later this evening due to the loss
of daytime heating as well as much of the cloudiness. A cold front was
across northern MO, just south of UIN early this evening. This front
will sag slowly southward tonight and Wednesday with scattered
convection possible along and just north of this front. Latest
HRRR model run keeps UIN dry through 09z Wednesday, but there may
be at least isolated showers/storms in the UIN area late tonight
into Wednesday morning. Due to uncertainty in timing and coverage
may keep the UIN taf dry for now. With light surface winds, a
clearing sky, and high surface dew points there will likely be
some fog late tonight/early Wednesday morning mainly in SUS and
CPS. The light surface wind will become n-nely late Wednesday
morning and afternoon after fropa.
Specifics for KSTL: Will need to include at least VCTS in the STL
taf until 01Z this evening. Thunderstorms along with cloud cover
should dissipate later this evening. Should have scattered
diurnal cumulus clouds late Wednesday morning and afternoon as the
atmosphere becomes very unstable along the weakening cold front
which will sag southward through central MO. Will likely be
isolated to scattered thunderstorms Wednesday afternoon, but may
leave out of the STL taf for now. The surface wind will become
light later this evening, then become nely Wednesday afternoon as
the front sags south of STL.
GKS
&&
.LSX WATCHES/WARNINGS/ADVISORIES:
MO...HEAT ADVISORY until 8 PM CDT Wednesday FOR Audrain MO-Boone MO-
Callaway MO-Cole MO-Crawford MO-Franklin MO-Gasconade MO-
Iron MO-Madison MO-Moniteau MO-Montgomery MO-Osage MO-
Reynolds MO-St. Francois MO-Ste. Genevieve MO-Warren MO-
Washington MO.
EXCESSIVE HEAT WARNING until 8 PM CDT Wednesday FOR Jefferson MO-
Lincoln MO-St. Charles MO-St. Louis City MO-St. Louis MO.
EXCESSIVE HEAT WARNING until 8 PM CDT this evening FOR Pike MO.
HEAT ADVISORY until 8 PM CDT this evening FOR Monroe MO-Ralls MO.
IL...EXCESSIVE HEAT WARNING until 8 PM CDT Wednesday FOR Bond IL-
Calhoun IL-Clinton IL-Fayette IL-Greene IL-Jersey IL-
Macoupin IL-Madison IL-Marion IL-Monroe IL-Montgomery IL-
Randolph IL-St. Clair IL-Washington IL.
EXCESSIVE HEAT WARNING until 8 PM CDT this evening FOR Pike IL.
&&
$$
WFO LSX
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
329 PM EDT MON AUG 25 2014
.SYNOPSIS...
A WARM RIDGE OF HIGH PRESSURE WILL EXPAND EASTWARD ACROSS THE AREA
THROUGH LATE WEEK. TROPICAL CYCLONE CRISTOBAL WILL MOVE NORTH AND
NORTHEAST...PASSING SEVERAL HUNDRED MILES EAST OF THE CAROLINA COAST
TUESDAY NIGHT AND WEDNESDAY. A WARMING TREND WILL DEVELOP MID AND
LATE WEEK...WITH MORE TYPICAL LATE SUMMER WEATHER EXPECTED INTO THE
WEEKEND. THE RISK FOR SHOWERS AND THUNDERSTORMS WILL BE ON THE
INCREASE EARLY NEXT WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 300 PM MONDAY...COOL CANADIAN HIGH PRESSURE CENTERED OVER NEW
ENGLAND CONTINUES TO RIDGE DOWN THE COAST...CREATING FALL-LIKE
WEATHER ACROSS THE EASTERN CAROLINAS. TEMPS THIS AFTN HAVE STRUGGLED
ONLY INTO THE LOW 80S THANKS TO COOL NE FLOW AND WIDESPREAD CLOUD
COVER EAST OF I-95. THIS CLOUD COVER IS INCREASING THANKS TO MOIST
ADVECTION ON NE FLOW...AND SHOWERS HAVE OVERSPREAD THE COASTAL
PORTIONS OF THE CAPE FEAR REGION...AS EXPECTED...AND DEPICTED ON
HIGH RES HRRR THROUGH THIS AFTN. THESE SHOWERS DO NOT FEATURE
CONSIDERABLE DEPTH...AS COLUMN MOISTENING EXISTS ONLY TO ABOUT 10
KFT /700MB/...ABOVE WHICH VERY DRY AIR EXISTS EMBEDDED WITHIN A
SUBSIDENCE INVERSION THANKS TO STRENGTHENING MID-LEVEL RIDGE.
THEREFORE...DO NOT EXPECT ANY LIGHTNING THIS AFTN OR EVE...EVEN AS
SHOWERS BECOME SLIGHTLY MORE WIDESPREAD ALONG THE EASTERN THIRD OF
THE CWA INTO TONIGHT.
DRYING WILL OCCUR IN THE LOWER PORTIONS OF THE COLUMN AFTER
DARK...AND ANY SHOWER ACTIVITY WILL WANE BY MIDNIGHT. NE WINDS WILL
CONTINUE AT 10-15 MPH EVEN AFTER DARK...CONTINUING THE CAA...AND
ALLOWING TEMPS TO FALL TO 62-67...COOLEST NORTH...IN A DRY AND CLEAR
COLUMN.
&&
.SHORT TERM /TUESDAY THROUGH WEDNESDAY NIGHT/...
AS OF 300 PM MONDAY...NE FLOW WILL BEGIN TO ABATE LATER TUE AND
TUE NIGHT AS SURFACE HIGH PRESSURE DEVELOPS SOUTHWARD AND IN
CLOSER PROXIMITY TO THE EASTERN CAROLINAS. TROPICAL CYCLONE
CRISTOBAL WILL BE MOVING TO THE NE...HUGGING 70 DEG WEST LONGITUDE
AS IT MOVES NORTH OF OUR LATITUDE TUE NIGHT AND WED. NO DIRECT
IMPACTS FROM THE CYCLONE ARE EXPECTED. EXPANSIVE RIDGE ALOFT TO
OUR WEST WILL EXPAND EASTWARD AND ACROSS THE AREA WED AND WED
NIGHT AND THIS WILL BRING RISING HEIGHTS...INCREASING SUBSIDENCE AND
TEMPS MORE TYPICAL OF LATE SUMMER ACROSS THE EASTERN CAROLINAS.
WILL NOT INCLUDE ANY POPS THROUGH THE PERIOD. IT IS NOT IMPOSSIBLE
THAT A FEW SHOWERS OFFSHORE MANAGE TO BRUSH THE COAST ON TUE...BUT
THE RISK IS VERY SMALL. WILL CALL FOR AN ABUNDANCE OF SUNSHINE
THROUGH THE PERIOD EXCEPT FOR SOME STRATOCUMULUS WHICH MAY BRUSH
THE COAST TUE AND TUE NIGHT.
HIGHS WILL BE MAINLY IN THE LOWER TO MID 80S TUE AND IN THE UPPER
80S TO AROUND 90 ON WED. ALONG THE COAST...THE SEABREEZE SHOULD
HOLD TEMPS TO THE MID 80S WED AFTERNOON. LOWS WILL BE IN THE LOWER
TO MID 60S TUE NIGHT AND MAINLY UPPER 60S TO LOWER 70S WED NIGHT.
&&
.LONG TERM /THURSDAY THROUGH MONDAY/...
AS OF 300 PM MONDAY...THE FOCUS ON THE EXTENDED FORECAST NOW SHIFTS
TO THE END OF THE PERIOD WHEN A MORE ACTIVE PATTERN SHOULD
DEVELOP. MID LEVEL RIDGING WILL DOMINATE CONDITIONS THURSDAY
THROUGH SATURDAY . A BROAD MID LEVEL TROUGH WILL BREAK DOWN THE
RIDGE SLOWLY SUNDAY AND MONDAY WITH A MORE MOISTURE LADEN
SOUTHWEST FLOW DEVELOPING. AT THE SURFACE...HIGH PRESSURE WILL
PREVAIL AS WELL. THERE IS A BACKDOOR FRONT STILL IN THE PICTURE
FOR LATE THURSDAY AND FRIDAY BUT THIS SHOULD HAVE LITTLE IMPACT ON
THE ACTUAL FORECAST OTHER THAN TO BUMP THE TEMPERATURES BACK A
COUPLE OF DEGREES. REGARDING POPS...VALUES INCREASE FROM SLIGHT
CHANCE SATURDAY TO LOWER CHANCE BY MONDAY. THIS PRIMARILY OF
PRECIPITABLE WATER VALUES INCREASING FROM JUST UNDER AN INCH
FRIDAY TO WELL ABOVE TWO INCHES MONDAY. TEMPERATURES HOVER AROUND
CLIMATOLOGY LEANING TOWARD A DEGREE OR TWO ABOVE FOR THE MOST
PART.
&&
.AVIATION /18Z MONDAY THROUGH SATURDAY/...
AS OF 18Z...THE STRATOCU HAS BLOSSOMED OVER THE PAST COUPLE OF
HOURS. LOOK FOR AN MVFR STRATOCU CEILING THROUGH MOST OF THE
AFTERNOON...WITH PERIODS OF VFR AS THE CU SCATTERS. GUSTY
NORTHEAST WINDS WILL BE THE RULE...WITH A FEW BURSTS NEAR 25 KTS
ALONG THE IMMEDIATE COAST. THE TROPICAL SYSTEM OFFSHORE WILL NOT
BE A FACTOR TODAY...ALTHOUGH IT MAY ENHANCE THE GRADIENT SLIGHTLY.
DIMINISHING WINDS THIS EVENING WITH CLEARING SKIES. SOME LIGHT FOG
IS POSSIBLE AT THE INLAND TERMINALS...BUT WINDS ALONG THE COAST
SHOULD BE HIGH ENOUGH TO PRECLUDE FOG. TUESDAY...CONTINUED
NORTHEAST FLOW...NOT AS STRONG AS TODAY HOWEVER.
EXTENDED OUTLOOK...EXPECT VFR CONDITIONS THROUGH THE EXTENDED
PERIOD. SLIGHT CHANCE OF SHOWERS FOR OUR NORTHERN TERMINALS FRI.
INCREASING CHANCES FOR PRECIP SATURDAY.
&&
.MARINE...
NEAR TERM /THROUGH TONIGHT/...
AS OF 300 PM MONDAY...HIGH PRESSURE CONTINUES TO RIDGE DOWN FROM NEW
ENGLAND JUST INLAND FROM THE WATERS...WHICH WHEN COMBINED WITH THE
PRESENCE OF TROPICAL STORM CRISTOBAL NEAR THE BAHAMAS PRODUCES A
PINCHED GRADIENT WITH GUSTY NE WINDS. THESE WINDS HAVE BEEN
SUSTAINED AT 15-20 KTS...WITH GUSTS ABOVE 25 KTS NEAR THE 20 NM
BOUNDARY AND OVER THE NORTHERN COASTAL WATERS. THIS IS EXPECTED TO
CONTINUE WITH LITTLE FLUCTUATION THROUGH THE PERIOD. SE SWELL FROM
CRISTOBAL HAS AMPLIFIED AND REACHED THE WATERS...AND IS SHOWING UP
AS 2-3FT/10SEC AT THE BUOYS. THIS SWELL...ALONG WITH A 5-7 FT NE
WIND WAVE...ARE TOGETHER IN THE WAVE SPECTRUM PRODUCING SIGNIFICANT
SEAS OF 4-7 FT THIS AFTN...WHICH WILL PERSIST INTO TUESDAY MORNING.
THE ONGOING SMALL CRAFT ADVISORY REMAINS UNCHANGED FOR THIS PERIOD
TO ACCOUNT FOR THE HAZARDOUS MARINE CONDITIONS.
SHORT TERM /TUESDAY THROUGH WEDNESDAY NIGHT/...
AS OF 300 PM MONDAY...THE PRESSURE DIFFERENCE BETWEEN HIGH
PRESSURE TO THE NORTH AND A TROPICAL CYCLONE WELL OFF THE
SOUTHEAST COAST WILL KEEP A RATHER TIGHT PRESSURE GRADIENT ACROSS
THE WATERS INTO TUE NIGHT. THE GRADIENT WILL RELAX SIGNIFICANTLY
WED AND WED NIGHT AS HIGH PRESSURE DOMINATES. WIND SPEEDS WILL BE
UP TO 20 KT TUE... BECOMING 10 KT OR LESS BY WED AFTERNOON. THE
DIRECTION WILL BE NE TUE...BUT WILL SLOWLY BACK TO NNE OR N TUE
NIGHT. THE DIRECTION WILL BECOME MORE SOUTHERLY DURING WED AS THE
SEABREEZE CIRCULATION DOMINATES. SEAS WILL BE UP TO 4 TO 6 FT
TUE...SUBSIDING TO 2 TO 4 FT BY WED AFTERNOON. A 10 TO 12 SECOND
SE SWELL IS EXPECTED THROUGH THE PERIOD.
LONG TERM /THURSDAY THROUGH SATURDAY/...
AS OF 300 PM MONDAY...VERY LIGHT WIND FIELDS THROUGH THE PERIOD
AS HIGH PRESSURE WILL PREVAIL AT ALL LEVELS OF THE ATMOSPHERE.
DIRECTIONS WILL GENERALLY BE FROM THE SOUTH WITH THE SEA BREEZE
BACKING THE DIRECTION EACH AFTERNOON CLOSER TO THE COAST. ALL
SPEEDS ARE WITHIN A COUPLE OF KNOTS EITHER SIDE OF TEN KNOTS.
BENIGN SEAS WILL PREVAIL THROUGH THE PERIOD WITH 1-3 FEET.
&&
.TIDES/COASTAL FLOODING...
AS OF 300 PM MONDAY...RIDGE OF HIGH PRESSURE CENTERED OVER NEW
ENGLAND CONTINUES TO RIDGE DOWN THE COAST...WITH THE AXIS JUST
INLAND FROM THE SHORE. THIS LEAVES THE WATERS SANDWICHED BETWEEN THE
HIGH...AND TROPICAL STORM CRISTOBAL NEAR THE BAHAMAS...PRODUCING
PERSISTENT AND STRONG NE WINDS LOCALLY. THESE NE WINDS ARE PUSHING
WATER TOWARDS SHORE...AND LOCAL TIDAL ANOMALIES ARE RUNNING +1 TO +2
FT TODAY. THESE ANOMALIES WILL RISE ON TOP OF A NEW-MOON ENHANCED
ASTRONOMICAL HIGH TIDE THIS EVENING...TO PRODUCE MINOR COASTAL
FLOODING ALONG ALL EAST FACING BEACHES. HIGH TIDE IS AROUND 8PM THIS
EVENING...AND MINOR COASTAL FLOOD THRESHOLDS MAY BE EXCEEDED FOR
ABOUT A 1 HR WINDOW BOTH SIDES OF HIGH TIDE. A COASTAL FLOOD
ADVISORY HAS AGAIN BEEN ISSUED FOR THE EAST FACING BEACHES OF THE
CAPE FEAR REGION...AS WELL AS THE ENTIRE GRAND STRAND OF SOUTH
CAROLINA.
&&
.ILM WATCHES/WARNINGS/ADVISORIES...
SC...COASTAL FLOOD ADVISORY FROM 7 PM TO 10 PM EDT THIS EVENING FOR
SCZ054-056.
NC...COASTAL FLOOD ADVISORY FROM 7 PM TO 10 PM EDT THIS EVENING FOR
NCZ106-108.
MARINE...SMALL CRAFT ADVISORY UNTIL 8 PM EDT TUESDAY FOR
AMZ250-252-254- 256.
&&
$$
NEAR TERM...JDW
SHORT TERM...RJD
LONG TERM...SHK
AVIATION...JDW/DL
TIDES/COASTAL FLOODING...JDW
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
150 AM EDT MON AUG 25 2014
.SYNOPSIS...
HIGH PRESSURE WILL EXPAND SOUTH ACROSS THE AREA OVERNIGHT AND
WEDNESDAY...BRINGING COOL AND DRY WEATHER. TROPICAL STORM
CRISTOBAL MAY BECOME A HURRICANE IN THE NEXT FEW DAYS AS IT PASSES
SEVERAL HUNDRED MILES EAST OF THE CAROLINAS. A WARMING TREND WILL
DEVELOP LATE IN THE WEEK. A BACKDOOR FRONT MAY APPROACH BY NEXT
WEEKEND...BRINGING A RISK FOR SHOWERS AND THUNDERSTORMS.
&&
.NEAR TERM /UNTIL 6 AM THIS MORNING/...
AS OF 1:50 AM MONDAY...MOST PLACES WILL REMAIN CLEAR
OVERNIGHT...WITH SOME PATCHES OF STRATO-CU ALONG THE COAST.
TEMPERATURES NOW DOWN INTO THE 60S MOST LOCATIONS. NO CHANGES TO
THE FORECAST WITH THE LATEST UPDATE. PREVIOUS DISCUSSIONS FOLLOW:
ASIDE FROM A FEW PATCHES OF STRATOCUMULUS NEAR THE BEACHES SKIES
ARE CLEAR AND SHOULD REMAIN MOSTLY CLEAR OVERNIGHT. THE 00Z MHX
SOUNDING SHOWED A CLEAR SUBSIDENCE INVERSION AT 5300 FEET AGL AND
MATCHED 18Z MODEL PROJECTIONS CLOSELY. THE ONLY CHANGE WITH THIS
UPDATE WAS TO LOWER DEWPOINT FORECASTS BY A FEW DEGREES THROUGH
THE NIGHT BASED ON CURRENT OBS AND THE 00Z MHX SOUNDING. PREVIOUS
DISCUSSION FROM 730 PM FOLLOWS...
AN EXTENSIVE STRATOCUMULUS DECK INLAND IS BEGINNING TO DECAY NOW
THAT THE SUN IS SETTING. SKIES SHOULD BECOME GENERALLY CLEAR
OVERNIGHT AS DRIER AIR ARRIVES IN THE 850 MB LAYER NEAR THE TOP OF
TODAY`S SURFACE MIXED LAYER. BESIDES DOWNWARD ADJUSTMENTS TO SKY
COVER...NO SIGNIFICANT CHANGES HAVE BEEN MADE TO THE FORECAST.
PREVIOUS DISCUSSION FROM 300 PM FOLLOWS...
COOL BUT BEAUTIFUL LATE SUMMER AFTERNOON COMING TO AN END...LEAVING
WHAT WILL BE ONE OF THE COOLER NIGHTS THIS AREA HAS SEEN IN QUITE
SOME TIME.
COLD FRONT CONTINUES TO SAG WELL SOUTH OF THE AREA...AND HAS PUSHED
TO NEARLY THE FLORIDA STATE LINE TODAY. DRIVING THIS BOUNDARY IS A
STRONG RIDGE OF HIGH PRESSURE OF CANADIAN ORIGIN...WITH THE CENTER
OF THIS HIGH ACTUALLY WELL NORTH OF WINNIPEG, CANADA IN THE NORTH
CENTRAL PART OF THE COUNTRY. THIS HIGH IS RIDGING INTO NEW ENGLAND
AND THEN DOWN THE EASTERN SEABOARD...WITH ABNORMALLY COOL AND DRY
AIR FOR LATE AUGUST FILTERING INTO THE REGION. THIS AIR MASS IS VERY
FALL-LIKE...AND DEWPOINTS HAVE FALLEN INTO THE LOW AND MID 60S
AREA-WIDE TODAY. THIS DRY AIR HAS LIMITED TOTAL INSTABILITY...AND
ALTHOUGH HIGH-RES GUIDANCE CONTINUES TO SUGGEST THE POTENTIAL FOR
ISOLATED SEA-BREEZE SHOWERS THROUGH THIS EVE...THE CHANCE FOR THAT
IS WANING...AND EVEN DIURNAL CU IS HAVING TROUBLE GAINING MUCH
AGITATION. STILL CONTINUED JUST VERY SCHC ALONG THE SC PORTION OF
THE SEA BREEZE FOR THE NEXT FEW HOURS. IF A SHOWER DOES DEVELOP IT
WILL ERODE QUICKLY AFTER DARK...AS WILL THE MAJORITY OF THE CLOUD
COVER.
NE WINDS WILL REMAIN ELEVATED TONIGHT...LIKELY STAYING 5-10 MPH INTO
MONDAY MORNING. THESE WINDS WILL CONTINUE TO ADVECT COOL/DRY
AIR...THUS DRIVING MINS WELL BELOW 70...WITH LOWER 60S ENCOMPASSING
THE NORTHERN HALF OR 2/3 OF THE CWA. WHILE ELEVATED WINDS TEND TO
LIMIT OVERALL COOLING...NE WINDS HAVE A TENDENCY TO COOL THE AREA
MORE THAN WOULD TYPICALLY BE EXPECTED...ESPECIALLY ACROSS THE CAPE
FEAR REGION. FOR THIS REASON HAVE FORECAST THE LOWEST TEMPS IN THE
NE ZONES TONIGHT...AND WILMINGTON MAY SEE ITS COOLEST NIGHT SINCE
EARLY JUNE.
&&
.SHORT TERM /6 AM THIS MORNING THROUGH TUESDAY NIGHT/...
AS OF 300 PM SUNDAY...THE FORECAST AREA WILL REMAIN IN THE GRIP OF
AN UNSEASONABLE NE FLOW AS HIGH PRESSURE CENTERED ACROSS THE
NORTHEAST U.S. RIDGES SOUTH...WITH ITS AXIS REMAINING TO THE WEST OF
OUR FORECAST AREA. AT THE SAME TIME...SLOW STRENGTHENING OF THE VERY
SLOW MOVING TROPICAL STORM ACROSS THE BAHAMAS IS EXPECTED. THIS WILL
SERVE TO PROLONG THE RATHER TIGHT PRESSURE GRADIENT BETWEEN THESE
TWO SYSTEMS.
AS THESE NE WINDS PERSIST...THEY WILL SERVE TO PILE UP WATER ON THE
IMMEDIATE COAST. THIS IN COMBINATION WITH THE NEW MOON WILL INCREASE
THE RISK FOR MINOR BEACH EROSION FOR THOSE BEACHES EXPOSED TO A NE
FETCH AND MINOR COASTAL FLOODING DURING THE NIGHTTIME HIGH TIDE...
BOTH AT THE BEACHES AND ALONG THE LOWER CAPE FEAR RIVER. OTHER
HAZARDS WILL INCLUDE A STRONG LONG SHORE CURRENT...MODERATE TO
PERHAPS STRONG RIP CURRENTS AND HIGHER THAN NORMAL...ROUGH SURF.
TEMPS WILL BE COOL IN THIS BREEZY NE FLOW REGIME. HIGHS WILL BE
IN THE LOWER TO MID 80S...WITH TUE PERHAPS SLIGHTLY COOLER THAN
MON. LOWS WILL BE IN THE LOWER TO MID 60S WITH PERHAPS UPPER 60S
AT THE BEACHES. WIND SPEEDS ON MON WILL BE UP TO 10 TO 20 MPH WITH
HIGHER GUSTS...ESPECIALLY AT THE BEACHES.
OFFSHORE SHOWERS ARE EXPECTED TO REMAIN THERE FOR MUCH OF THE
PERIOD. TRAJECTORIES WILL AT TIMES BRING THE SHOWERS VERY NEAR THE
BEACHES...BUT GIVEN THE DRYNESS OF THE COLUMN...EXPECT THESE SHOWERS
TO LARGELY ERODE BEFORE MOVING ONSHORE.
&&
.LONG TERM /WEDNESDAY THROUGH SUNDAY/...
AS OF 300 PM SUNDAY...THE MID LEVEL PATTERN WILL SHOW TYPICAL LATE
SUMMER LETHARGY THROUGH THE PERIOD AS RIDGING WILL BE THE CENTRAL
THEME.
THE AXIS OF THE RIDGE MOVES FROM THE MISSISSIPPI VALLEY TO OFF THE
PENINSULA OF FLORIDA BY THE END OF THE PERIOD. AT THE SURFACE...WEAK
HIGH PRESSURE WILL PREVAIL AS WELL AND AS THE MID LEVEL RIDGE
REPOSITIONS...A RELATIVELY WEAK BACKDOOR FRONT WILL MOVE ACROSS
FRIDAY. THIS WILL SERVE TO ENHANCE THE POPS BOTH FRIDAY AND
SATURDAY. HOWEVER MOISTURE AND FORCING REMAIN RELATIVELY WEAK AND
SLIGHT CHANCE FRIDAY TO LOW CHANCE SATURDAY WILL SUFFICE FOR NOW.
THERE IS ALSO SLIGHT CHANCE POPS FOR WEDNESDAY AND THURSDAY ALONG
THE COASTAL AREAS.
THE COOL REFRESHING AIRMASS WILL BE A THING OF THE PAST AS
TEMPERATURES WEDNESDAY THROUGH FRIDAY WILL BE AT OR JUST ABOVE
CLIMATOLOGY. FOR NEXT WEEKEND...A SLIGHT DROP IN TEMPERATURES IS
SEEN AS THE BACKDOOR FRONT MOVES ACROSS BUT JUST A COUPLE OF
DEGREES.
&&
.AVIATION /06Z MONDAY THROUGH FRIDAY/...
AS OF 06Z...VFR WILL PREVAIL THROUGH THIS TAF PERIOD. OTHER THAN
THE POSSIBILITY OF SOME MVFR STRATOCU CLIPPING THE COASTAL TERMS
EARLY THIS MORNING...MOSTLY CLEAR CONDITIONS WILL PERSIST THROUGH
THE OVERNIGHT HOURS. SREF PROBABILITIES CONTINUE TO DEPICT THE
MVFR CIGS STAYING WELL OFFSHORE...SO NO MENTION OF REDUCED CIGS IN
THE TAFS. NORTHEAST WINDS AROUND 10 KT WILL STRENGTHEN TO 10-15 KT
WITH GUSTS UP TO 20 KT AS HIGH PRESSURE CONTINUES WEDGING INTO THE
CAROLINAS TODAY. LOW LEVEL MOISTURE WILL REMAIN TRAPPED BENEATH
THE SUBSIDENCE INVERSION...SO EXPECT SCT 3-7KFT CU TO DEVELOP
AGAIN DURING THE DAY. BUT WITH EXTREMELY DRY AIR IN PLACE ABOVE
700 MB...THERE IS NO PCPN IN THE FORECAST THROUGH THE END OF THE
PERIOD.
EXTENDED OUTLOOK...EXPECT VFR CONDITIONS THROUGH THE EXTENDED
PERIOD. SLIGHT CHANCE OF SHOWERS FOR OUR NORTHERN TERMINALS FRI.
&&
.MARINE...
NEAR TERM /THROUGH TONIGHT/...
AS OF 1:30 AM MONDAY...NO CHANGES TO THE FORECAST WITH THE LATEST
UPDATE. PREVIOUS DISCUSSIONS FOLLOW:
WIND SPEEDS ARE RUNNING JUST A BIT HIGHER THAN FORECAST NEARSHORE
BUT LOOK GOOD OFFSHORE COMPARED TO BUOYS 41037 AND 41004. MARINE MOS
GUIDANCE AND LATEST RUC AND HRRR MODELS SUGGEST WIND SPEEDS WILL
BACK MORE NORTHERLY OVERNIGHT BUT WILL NOT DECREASE MUCH IN SPEED.
IN FACT THE ADVECTION OF COOLER AIR OVER THE VERY WARM OCEAN SURFACE
LATER TONIGHT WILL PROBABLY ENHANCE GUSTINESS AND DOWNWARD TRANSPORT
OF STRONGER WINDS FROM ALOFT. NO SIGNIFICANT CHANGES WERE MADE TO
THE FORECAST OVERNIGHT. PREVIOUS DISCUSSION FROM 300 PM FOLLOWS...
PINCHING NE GRADIENT EAST OF A RIDGE OF HIGH PRESSURE EXPANDING DOWN
THE COAST IS CAUSING DETERIORATING MARINE CONDITIONS TODAY. WINDS
ARE SLOWLY BUT STEADILY RISING OUT OF THE NE...WITH SPEEDS OF 15-20
KTS COMMON ACROSS THE WATERS...WITH SOME GUSTS APPROACHING 30 KTS
DEVELOPING OVER THE NORTHERN WATERS AND OUTSIDE OF 20 NM. AS THE
HIGH PRESSURE STRENGTHENS TONIGHT...THE GRADIENT WILL TIGHTEN
FURTHER...AIDED BY THE DISTANT BUT STRENGTHENING TROPICAL STORM
CRISTOBAL NEAR THE BAHAMAS. THIS WILL CAUSE WIDESPREAD 15-25 KT NE
WINDS THROUGH THE PERIOD...WITH SEAS BUILDING TO 5-8 FT.
WAVE HEIGHTS WILL BE DRIVEN ALMOST ENTIRELY BY A NE WIND CHOP
TONIGHT. HOWEVER...LONGER PERIOD SWELL ASSOCIATED WITH TROPICAL
STORM CRISTOBAL IS FORECAST TO BEGIN TO ENTER THE SPECTRUM TONIGHT.
ONLY NOTICEABLE LONG-SWELL PRESENTLY EXISTS AT 41004 /EDISTO BUOY/
WHICH IS OBSERVING A LOW-AMPLITUDE 13 SEC SWELL. EXPECT THIS TO
GRADUALLY LIFT NE INTO THE LOCAL WATERS...BUT HAVE ONLY MINIMAL
CONTRIBUTION TO THE SIGNIFICANT SEAS UNTIL MONDAY.
SHORT TERM /MONDAY THROUGH TUESDAY NIGHT/...
AS OF 300 PM SUNDAY...THE PRESSURE DIFFERENCE BETWEEN HIGH PRESSURE
TO THE NORTH AND A SLOWLY DEVELOPING TROPICAL STORM ACROSS THE
BAHAMAS WILL KEEP A TIGHT PRESSURE GRADIENT ACROSS THE WATERS. A
SMALL CRAFT ADVISORY REMAINS IN EFFECT. WINDS WILL COMMONLY BE
SUSTAINED AT 20 TO 25 KT. THE LONG NE FETCH WILL KEEP SEAS IN THE 4
TO 7 FT RANGE WITH AT LEAST 8 FT SEAS BEYOND 20 NM. A 10 TO 12
SECOND SE SWELL IS EXPECTED TO SLOWLY BUILD THROUGH THE PERIOD.
LONG TERM /WEDNESDAY THROUGH FRIDAY/...
AS OF 300 PM SUNDAY...CONFIDENCE CONTINUES TO BUILD THAT THE ONLY
IMPACTS FROM CRISTOBAL WILL BE THE SWELL COMPONENT ADDED TO THE WAVE
SPECTRUM. THE LATEST WAVEWATCH HURRICANE BULLETIN FOR FRYING PAN
SHOALS SHOWS 7-8 FEET DEVELOPING OR PERSISTING WEDNESDAY THROUGH
EARLY THURSDAY WITH A GOOD PORTION OF THIS BEING THE WIND WAVE
COMPONENT. THIS MAKES SENSE AS THE GFS IS NOT DEVELOPING THE SYSTEM
APPRECIABLY. FOR THE 0-20 MILE COASTAL WATERS 4-6 FEET WEDNESDAY AND
EARLY THURSDAY SHOULD SUFFICE. BY FRIDAY A WEAK PRESSURE PATTERN
YIELDS LIGHT WINDS AND SEAS. FOR THE WINDS WEDNESDAY AND
THURSDAY...A NORTHEASTERLY FLOW OF 10-15 KNOTS WEDNESDAY DROPS TO
SINGLE DIGITS THURSDAY.
&&
.ILM WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
NC...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 8 PM EDT TUESDAY FOR AMZ250-252-254-
256.
&&
$$
SYNOPSIS...RJD
NEAR TERM...REK/TRA/JDW
SHORT TERM...RJD
LONG TERM...SHK
AVIATION...REK/BJR
MARINE...REK/RJD/TRA/JDW/SHK
AREA FORECAST DISCUSSION
NWS BISMARCK ND
325 PM CDT MON AUG 25 2014
.SHORT TERM...(THIS EVENING THROUGH TUESDAY)
ISSUED AT 323 PM CDT MON AUG 25 2014
THE MAIN FORECAST ISSUES IN THE LONG TERM PERIOD WILL BE
TEMPERATURES TONIGHT AND PRECIPITATION CHANCES SOUTHWEST AND SOUTH
CENTRAL LATE TONIGHT AND TUESDAY. THE PESKY UPPER LOW IS NOW
LIFTING OUT OF THE AREA. ONE LAST TRAILING VORT COMBINED WITH
ANOTHER APPROACHING SHORTWAVE IS KEEPING A FEW SHOWERS OVER
NORTHEAST MONTANA AND NORTHWEST NORTH DAKOTA. THE 18Z HRRR SHOWS
THE SHOWERS HANGING ON THROUGH 00Z. WILL MENTION SOME SCATTED
SPRINKLES NORTHWEST LATE THIS AFTERNOON.
THE APPROACHING SHORTWAVE...IN COMBINATION WITH AN STRENGTHENING
UPPER LEVEL JET WILL PRODUCE INCREASING CLOUDS AND EVENTUALLY A
SWATH OF LIGHT PRECIPITATION...MOVING INTO THE SOUTHWEST LATE
TONIGHT AND SPREADING ACROSS THE SOUTHWEST AND SOUTH CENTRAL ON
TUESDAY. THE INCREASING CLOUDS SHOULD HELP TEMPER THE MERCURY DROP
LATE TONIGHT OVER THE SOUTHWEST. BUT WITH DECREASING CLOUDS...AND
DIMINISHING WINDS...MOST AREAS ARE EXPECTED TO FALL INTO THE
LOWER TO MIDDLE 40S. WOULD NOT BE SURPRISED TO SEE A FEW LOWS
INTO THE UPPER 30S.
.LONG TERM...(TUESDAY NIGHT THROUGH MONDAY)
ISSUED AT 323 PM CDT MON AUG 25 2014
A BROAD POSITIVELY TILTED TROUGH IS FORECAST TO HAVE MOVED EAST OF
THE FORECAST AREA BY TUESDAY NIGHT...WITH DRY CONDITIONS EXPECTED
TUESDAY NIGHT.
A WARMING TREND ALONG WITH DRY CONDITIONS ARE EXPECTED TO CONTINUE
WEDNESDAY THROUGH FRIDAY AS WEAK UPPER LEVEL RIDGING BUILDS OVER
THE NORTHERN PLAINS. NEAR NORMAL HIGHS ARE FORECAST BY FRIDAY.
THE UPPER RIDGE IS PROGGED TO BREAK DOWN SOMEWHAT BY FRIDAY
NIGHT...AND WEAK WAVES IN THE UPPER FLOW ALOFT WILL GENERATE CHANCES
FOR THUNDERSTORMS EACH PERIOD FRIDAY NIGHT THROUGH MONDAY. NEAR
NORMAL TEMPERATURES ARE EXPECTED TO CONTINUE THROUGH THE WEEKEND AND
INTO MONDAY.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON)
ISSUED AT 323 PM CDT MON AUG 25 2014
MVFR TO LOW VFR CEILINGS ARE EXPECTED TO ALL LIFT TO LOW VFR
AROUND 22 UTC. NORTHWEST SURFACE FLOW WILL DIMINISH FROM WEST TO
EAST AFTER 21 UTC. VFR CONDITIONS ARE EXPECTED ACROSS TAF SITES
TONIGHT AND TUESDAY MORNING.
&&
.HYDROLOGY...
ISSUED AT 323 PM CDT MON AUG 25 2014
HEAVY RAINFALL IN THE PAST COUPLE OF DAYS HAVE CAUSED OVERLAND
FLOODING...AS WELL AS RISES IN CREEKS...RIVERS...AND STREAMS IN
PARTS OF SOUTH CENTRAL NORTH DAKOTA - ESPECIALLY WEST OF THE
MISSOURI RIVER. SIOUX...GRANT...AND WESTERN MORTON COUNTIES SAW
LARGE AREAS OF 2 TO 4 INCHES OF RAIN.
AN AREAL FLOOD WARNING REMAINS IN EFFECT FOR PARTS OF WESTERN MORTON
COUNTY AND PARTS OF NORTHERN GRANT COUNTY. THESE AREAS INCLUDE THE
BIG MUDDY CREEK BETWEEN GLEN ULLIN AND ALMONT...SOUTHWARD TO
HEIL...CARSON...AND LARK. THESE AREAS CONTAIN SMALL CREEKS AND
STREAMS THAT ARE TRIBUTARIES TO THE HEART RIVER.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...TWH
LONG TERM...JV
AVIATION...TWH
HYDROLOGY...TWH
AREA FORECAST DISCUSSION
NWS CLEVELAND OH
410 PM EDT MON AUG 25 2014
.SYNOPSIS...
TEMPERATURES WILL CONTINUE TO WARM ACROSS THE REGION WITH A STRONG
UPPER LEVEL RIDGE ALOFT. HIGH PRESSURE AT THE SURFACE WILL REMAIN
ALONG THE EAST COAST ON TUESDAY WHILE LOW PRESSURE OVER ONTARIO
PASSES NORTH OF THE GREAT LAKES. THE ASSOCIATED COLD FRONT WILL PUSH
SOUTH ACROSS THE AREA LATE TUESDAY NIGHT INTO WEDNESDAY...FOLLOWED
BY HIGH PRESSURE BUILDING EAST ACROSS THE GREAT LAKES ON THURSDAY.
&&
.NEAR TERM /THROUGH TUESDAY NIGHT/...
THE FORECAST AREA REMAINS BENEATH A STRONG UPPER LEVEL RIDGE ALOFT
WITH SURFACE HIGH PRESSURE TO THE EAST AND A TROUGH MOVING INTO THE
WESTERN GREAT LAKES. THERE IS ABOUT A 10 DEGREE SPREAD IN BOTH
TEMPERATURES AND DEWPOINTS ACROSS THE AREA LATE THIS AFTERNOON AS A
VERY WARM AND HUMID AIRMASS SPREADS INTO NW OHIO WHILE SEASONABLE
CONDITIONS REMAIN IN WESTERN PENNSYLVANIA.
MAIN FORECAST CONCERN FOR TONIGHT REVOLVES AROUND THE EVOLUTION OF
THE MCS MOVING INTO NW INDIANA. A VERY UNSTABLE ENVIRONMENT IS IN
PLACE ACROSS NRN ILLINOIS AND WESTERN INDIANA...WITH INSTABILITY
DECREASING INTO WESTERN OHIO WHERE ML CAPES ARE CLOSER TO 1000-1500
J/KG. STORM MOTION HAS BEEN TOWARDS THE SOUTH SOUTHEAST TOWARDS THE
BETTER INSTABILITY OVER THE LAST HOUR OR TWO WITH GENERALLY WEAK
FLOW ALOFT. 850-300MB FLOW IS WESTERLY IN WESTERN INDIANA THEN
BECOMES MORE NORTHWESTERLY TO THE EAST. THE LATEST RUN OF THE HRRR ALSO
SHOWS THIS ACTIVITY TRACKING TO THE SOUTHEAST AND HAVE ADDED A
CHANCE OF THUNDERSTORMS FOR THIS EVENING INTO NW OHIO. OUT OF AHEAD
OF THIS COMPLEX WE ARE ALSO SEEING SOME SMALL SHOWERS POPPING UP IN
EXTREME NW OHIO BUT THESE WILL LIKELY STRUGGLE WITH THE CAP STILL IN
PLACE. THE SEVERE WEATHER THREAT REMAINS SOMEWHAT UNCLEAR AT THIS
TIME. ONLY ONE WARNING HAS BEEN ISSUED IN NRN INDIANA AND THERE HAVE
BEEN NO REPORTS OF SEVERE WEATHER AS OF 345 PM EDT. SHEAR SHOULD BE
A LIMITING FACTOR AND THE LATEST RADAR IMAGERY SUGGESTS THE GUST
FRONT MAY BE OUTPACING THE DEEPER CONVECTION. THIS WOULD LIMIT THE
SEVERE POTENTIAL AS WE HEAD INTO THIS EVENING.
OTHERWISE THERE IS ALSO A CHANCE OF SHOWERS AND THUNDERSTORMS
SINKING SOUTH ACROSS LOWER MICHIGAN OVERNIGHT TOWARDS NW OHIO AND
WILL KEEP A LOW POP IN THE FORECAST FOR OVERNIGHT. SEVERE WEATHER IS
NOT EXPECTED LATER TONIGHT.
&&
.SHORT TERM /WEDNESDAY THROUGH THURSDAY NIGHT/...
SHOWERS AND THUNDERSTORMS SHOULD GENERALLY BE LOCATED NORTH OF THE
AREA TO START THE DAY ON TUESDAY. INSTABILITY AND DEEP MOISTURE AXIS
WILL CONTINUE TO INCREASE OVER THE AREA WITH A WEST SOUTHWESTERLY
FLOW AHEAD OF THE APPROACHING FRONT. TEMPERATURES WILL APPROACH 90
DEGREES IN NW OHIO WITH DEWPOINTS CLIMBING INTO THE LOW 70S. THIS
WILL PUSH HEAT INDEX VALUES TO AROUND 95 DEGREES WHICH WILL BE NEAR
THE HOTTEST CONDITIONS EXPERIENCED ALL SUMMER TOWARDS THE I-75
CORRIDOR. SHOWERS AND THUNDERSTORMS ARE EXPECTED TO FILL IN AS THE
FRONT SINKS SOUTH TOWARDS NW OHIO DURING THE AFTERNOON. THE FRONT IS
EXPECTED TO BE FAIRLY SLOW MOVING DURING THE AFTERNOON...DEPENDING
ON THE EVOLUTION OF THE CONVECTION. A SERIES OF SHORTWAVES WILL
ROUND THE RIDGE AND PUSH THE FRONTAL BOUNDARY SOUTHWARD OVERNIGHT.
NUMEROUS SHOWERS AND THUNDERSTORMS ARE EXPECTED ON LAKE ERIE TUESDAY
NIGHT...SINKING SOUTH ACROSS THE EASTERN CWA OVERNIGHT. GIVEN THE
VERY MOIST AIRMASS AND MOVEMENT ALONG THE FRONT...VERY HEAVY RAIN
WILL BE POSSIBLE WITH THUNDERSTORMS ON TUESDAY NIGHT AND WILL HAVE
TO CONSIDER THE POTENTIAL FOR LOCALIZED FLOODING.
THE FRONT STILL LOOKS TO PUSH SOUTH ACROSS THE AREA ON WEDNESDAY
MORNING SO WILL CONTINUE WITH SHOWERS AND THUNDERSTORMS ENDING
DURING THE MORNING. THE TIMING OF THE CONVECTION DURING THE TUESDAY
NIGHT INTO WEDNESDAY MORNING IS NOT REAL FAVORABLE FOR SEVERE
THUNDERSTORMS. LOWERED HIGHS ON WEDNESDAY SEVERAL MORE DEGREES WITH
BACK INTO THE MID 70S TO LOWER 80S. HIGH PRESSURE WILL BUILD IN
BEHIND THE FRONT ON WEDNESDAY NIGHT AND THURSDAY.
&&
.LONG TERM /FRIDAY THROUGH MONDAY/...
I THINK THE KEY FOR THE LONG TERM PORTION OF THE FORECAST IS THE
PROGRESSION OF THE TROUGH EASTWARD FROM THE ROCKIES. MOST OF THE
MORE RELIABLE GUIDANCE SHOWS THE TROUGH APPROACHING BY SUNDAY BUT
THERE IS STILL A LOT OF UNCERTAINTY.
IN THE MEAN TIME...THE STALLED SURFACE FRONT WILL RETURN NORTH AS A
WARM FRONT ON FRIDAY. NOT SURE HOW MUCH COVERAGE OF SHOWERS AND
THUNDERSTORMS THERE MIGHT BE...THE GFS SEEMS TYPICALLY TOO STRONG
AND TOO FAR NORTH WITH THE SURFACE WAVE. AND SOME OF THE OTHER
MODELS HAVE THE CONVECTIVE FEEDBACK LOOK. WILL HAVE A CHANCE OF
SHOWERS AND STORMS FRIDAY INTO SATURDAY. IT WOULD SEEM THAT THE WARM
SECTOR SHOULD MAKE PROGRESS NORTHWARD INTO THE AREA BY THE WEEKEND
BUT WILL NOT GO ALL OUT ON TEMPS YET FOR SATURDAY UNTIL A LITTLE
MORE CONFIDENT OF THE TIMING. THE FORECAST WILL HAVE HIGHS IN THE
LOWER AND MID 80S ON SATURDAY BUT TEMPS COULD TAKE A RUN TOWARD 90F.
AS MENTIONED BEFORE...THE THUNDERSTORMS SHOULD INCREASE ON SUNDAY
BUT WILL ONLY GO FOR A 50 PERCENT CHANCE FOR NOW...NOT YET
COMFORTABLE FORECASTING "LIKELY" GIVEN THE UNCERTAINTY.
THE FRONT MAY BE THROUGH THE AREA ON MONDAY LABOR DAY AND PERHAPS
THE SHOWER THREAT WILL MOVE EAST WITH SOMEWHAT COOLER TEMPS.
&&
.AVIATION /18Z MONDAY THROUGH SATURDAY/...
A RELATIVELY SMALL CUMULUS FIELD WAS SPREADING OUT ACROSS NORTH
CENTRAL OHIO BUT THE CUMULUS SHOULD SCATTER OUT DURING THE MID TO
LATE AFTERNOON AND EVENTUALLY EVAPORATE THIS EVENING. HIGH CLOUDS
WILL SPREAD ACROSS THE AREA FROM THE THUNDERSTORMS IN MICHIGAN AND
SCATTERED TO BROKEN ALTOCUMULUS WILL PROBABLY DEVELOP IN THE EARLY
MORNING HOURS ON TUESDAY. THERE IS AN OUTSIDE CHANCE THAT SHOWERS
OR THUNDERSTORMS COULD SNEAK INTO NORTHWEST OHIO TUESDAY MORNING
BUT WILL NOT INCLUDE IT IN THE TAF FORECASTS AT THIS TIME.
OUTLOOK...NON VFR POSSIBLE TUESDAY EVENING INTO WEDNESDAY MORNING
IN SHOWERS AND THUNDERSTORMS.
&&
.MARINE...
THE SOUTHEAST FLOW ON THE LAKE WILL BE LOCALLY ONSHORE EARLY THIS
EVENING OTHERWISE IT WILL CONTINUE TO VEER MORE FROM THE SOUTH AND
THEN SOUTHWEST AHEAD OF THE NEXT COLD FRONT. THE TIMING ON THE FRONT
STILL SEEMS TO BE LATE TUESDAY NIGHT OR EARLY WEDNESDAY. THE FLOW
SHOULD BECOME NORTHERLY SOON AFTER THE FRONTAL PASSAGE. THE
GRADIENT AHEAD OF THE FRONT AND BEHIND THE FRONT IS LIGHT TO
MODERATE BUT EVEN A MODERATE NORTH WIND MAY APPROACH SMALL CRAFT
ADVISORY CONDITIONS LATER WEDNESDAY INTO WEDNESDAY NIGHT. THE HIGH
PRESSURE SYSTEM IS EXPECTED TO CROSS EASTERN CANADA SO THE FLOW
SHOULD VEER MORE EASTERLY BY THURSDAY NIGHT AND SOUTHEAST AND SOUTH
AGAIN BY THE WEEKEND.
&&
.CLE WATCHES/WARNINGS/ADVISORIES...
OH...NONE.
PA...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...KEC
NEAR TERM...KEC
SHORT TERM...KEC
LONG TERM...KOSARIK
AVIATION...KOSARIK
MARINE...KOSARIK
AREA FORECAST DISCUSSION...UPDATED
NWS MORRISTOWN TN
1002 AM EDT MON AUG 25 2014
.DISCUSSION...
A BROAD UPPER-LEVEL HIGH PRESSURE RIDGE WILL CONTINUE TO BUILD INTO
THE TENNESSEE VALLEY TODAY...AND BECOME THE DOMINANT WEATHER
FEATURE ACROSS THE AREA FOR THE NEXT SEVERAL DAYS. HOWEVER FOR
TODAY...MOISTURE STILL PRESENT UNDERNEATH THIS RIDGE HAS RESULTED IN
SCATTERED TO LOCALLY DENSE CLOUD COVER THIS MORNING /ALONG WITH A
COUPLE OF ROGUE SHOWERS OVER THE PLATEAU/. AS DRY AIR BEGINS TO
WORK ITS WAY INTO THE REGION...THIS CLOUD COVER WILL GRADUALLY
BREAK UP AND SHIFT OFF TO THE WEST...RESULTING IN A MOSTLY TO
PARTLY SUNNY DAY ACROSS THE REGION. GIVEN THE STRONGER CAP
DEVELOPING ALOFT...AM NOT EXPECTING MUCH IN THE WAY OF CONVECTION
THIS AFTERNOON. BUT...THE HRRR IN PARTICULAR DOES HINT AT SOME
ISOLATED SHOWERS/STORMS DEVELOPING AFTER 18Z ALONG THE PLATEAU...
SO HAVE ADDED A SOME LOW-END MENTIONABLE POPS IN THIS AREA THIS
AFTERNOON. HIGHS WILL BE SLIGHTLY COOLER TODAY WITH THE CLOUD
COVER...BUT WILL STILL REACH THE MID TO UPPER 80S TODAY.
&&
.PRELIMINARY POINT TEMPS/POPS...
CHATTANOOGA AIRPORT, TN 88 67 91 66 / 20 0 0 10
KNOXVILLE MCGHEE TYSON AIRPORT, TN 87 65 88 64 / 10 0 0 10
OAK RIDGE, TN 87 66 89 64 / 10 0 0 10
TRI CITIES AIRPORT, TN 86 56 86 61 / 10 0 10 10
&&
.MRX WATCHES/WARNINGS/ADVISORIES...
NC...NONE.
TN...NONE.
VA...NONE.
&&
$$
AMP
AREA FORECAST DISCUSSION
NWS MEMPHIS TN
1209 AM CDT MON AUG 25 2014
.UPDATE... /ISSUED 902 PM CDT SUN AUG 24 2014/
SKIES ARE MOSTLY CLEAR OVER MUCH OF THE FORECAST AREA THIS
EVENING WITH TEMPERATURES RANGING FROM THE LOWER 70S TO MID 80S.
ALL OF THE THUNDERSTORM ACTIVITY THAT WAS OVER THE FORECAST AREA
EARLIER THIS EVENING HAS ENDED AND NO ADDITIONAL THUNDERSTORMS ARE
EXPECTED FOR THE REMAINDER OF TONIGHT. WILL UPDATE FORECAST TO
REMOVE ANY MENTION OF RAIN TONIGHT.
ARS
&&
.DISCUSSION... /ISSUED 615 PM CDT SUN AUG 24 2014/
NQA RADAR BACK IN SERVICE AND JUST IN TIME TO SHOW CONVECTION
DEVELOPING IN NORTH MISSISSIPPI. TEMPERATURES WERE MAINLY IN THE
90S ACROSS THE MIDSOUTH WITH A RECORD 100 DEGREES...THE WARMEST
READING SINCE AUGUST 2012...AT THE MEMPHIS INTERNATIONAL AIRPORT.
FOR THE REMAINDER OF TODAY AND TONIGHT...SHORT TERM HRRR MODEL
SHOWING CONVECTION BECOMING SCATTERED BY 4 PM FOR POINTS ALONG
AND WEST OF THE MISSISSIPPI RIVER...WHICH CURRENTLY LINES UP WITH
PW`S ABOVE 1.80 INCHES. COULDN`T RULE OUT AN ISOLATED WET
MICROBURST WITH THE STRONGEST STORMS. ACTIVITY WILL WANE BY 9 PM
LEAVING SKIES PARTLY CLOUDY OVERNIGHT. THIS SHOULD HELP KEEP MORE
HEAT IN...WITH OVERNIGHT LOWS AGAIN IN THE MID AND UPPER 70S.
MONDAY AND TUESDAY...A WEAK DISTURBANCE WILL MOVE WESTWARD ALONG
THE GULF COAST/SOUTHSIDE OF THE UPPER RIDGE...AND AS IT DOES
EASTERLY WINDS IN THE BOUNDARY LAYER AND MIDLEVELS WILL SLIDE
DRIER AIR OFF THE APPALACHIANS IN ITS WAKE. HEAT INDICES WILL
CONTINUE TO FLIRT WITH 105F TOMORROW...DESPITE MORE CLOUD COVER
AND CONVECTION. FEEL BY TUESDAY ENOUGH DRY AIR WILL HAVE
OVERSPREAD THE MIDSOUTH TO REDUCE HEAT INDICES BELOW 105F.
ISOLATED STORMS WILL BE POSSIBLE ON TUESDAY BUT MAINLY WEST OF THE
MISSISSIPPI RIVER NEAR THE FRONT EDGE OF THE DRIER AIR.
WEDNESDAY THROUGH FRIDAY...MODELS ARE IN GOOD AGREEMENT THAT THE
UPPER RIDGE WILL REMAIN OVER THE REGION...BUT STRONGER SUBSIDENCE
WILL KEEP DEWPOINTS IN THE 60S AND LOWER RAIN CHANCES TO AROUND 10
PERCENT. TEMPERATURES WILL BE IN THE LOW TO MID 90S WITH AFTERNOON
HEAT INDICES IN THE 93-100F RANGE.
NEXT WEEKEND...THE GFS AND EURO ARE BECOMING BETTER ALIGNED THAT
THE RIDGE WILL FLATTEN IN RESPONSE TO AN APPROACHING CENTRAL
PLAINS SHORTWAVE. THIS DISTURBANCE NOW APPEARS SOMEWHAT WEAKER AND
OUT OF PHASE WITH THE MAIN UPPER LEVEL FLOW. NONETHELESS MOISTURE
OUT AHEAD OF THE SYSTEM WILL MOVE OVER THE OZARKS ON SATURDAY AND
INTO THE MIDSOUTH BY EARLY SUNDAY. HAVE BUMPED UP TEMPERATURES TO
MAINLY THE LOW 90S FOR HIGHS AND KEPT A CONSERVATIVE APPROACH TO
THE RAIN CHANCES.
JAB
&&
.AVIATION...
06Z TAF CYCLE
ISOLATED TO SCATTERED TSRA ARE EXPECTED TO DEVELOP MONDAY AFTERNOON
AROUND THE KMEM...KMKL...AND KTUP TAF SITES...MENTIONED VCTS FOR
THESE SITES. OTHERWISE VFR CONDITIONS WILL PREVAIL DURING THE
PERIOD...THE EXCEPTION POSSIBLY BEING MVFR CONDITIONS IN FOG AT KMKL
EARLY MONDAY MORNING. WINDS TONIGHT EASTERLY 5 KTS OR LESS. WINDS
MONDAY E-SE 4-6 KTS. WINDS MONDAY NIGHT E 5 KTS OR LESS.
JCL/KRM
&&
&&
.MEG WATCHES/WARNINGS/ADVISORIES...
AR...HEAT ADVISORY UNTIL 7 PM CDT THIS EVENING FOR CLAY-CRAIGHEAD-
CRITTENDEN-CROSS-GREENE-LAWRENCE-LEE AR-MISSISSIPPI-
PHILLIPS-POINSETT-RANDOLPH-ST. FRANCIS.
MO...HEAT ADVISORY UNTIL 7 PM CDT THIS EVENING FOR DUNKLIN-PEMISCOT.
MS...HEAT ADVISORY UNTIL 7 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 7 PM CDT THIS EVENING FOR BENTON TN-CARROLL-
CHESTER-CROCKETT-DECATUR-DYER-FAYETTE-GIBSON-HARDEMAN-
HARDIN-HAYWOOD-HENDERSON-HENRY-LAKE-LAUDERDALE-MADISON-
MCNAIRY-OBION-SHELBY-TIPTON-WEAKLEY.
&&
$$
AREA FORECAST DISCUSSION...UPDATED
NWS CORPUS CHRISTI TX
943 PM CDT TUE AUG 26 2014
.DISCUSSION...SATELLITE IMAGERY SHOWS THE MID LEVEL LOW OVER THE
NORTHERN GULF OF MEXICO SOUTH OF LAKE CHARLES. THE SURFACE TROUGH
AXIS EXTENDS ACROSS THE GULF OF MEXICO FROM THE YUCATAN CHANNEL
NORTHWEST TO THE UPPER TEXAS COAST. 00Z CRP SOUNDING INDICATED AN
INCREASE IN MOISTURE OVER THE REGION UP TO 2 INCHES...WHILE GOES
SOUNDER SHOWS HIGHER MOISTURE OVER THE NORTHWEST GULF OF MEXICO
NEAR THE MID LEVEL LOW. THIS MOISTURE WILL BE MOVING INTO THE
COASTAL WATERS OVERNIGHT. LATEST RUNS OF NAM/GFS SHOWED AN INCREASE
IN LOW LEVEL CONVERGENCE OVER THE COASTAL WATERS LATE TONIGHT INTO
WEDNESDAY MORNING. HI RES MODELS FROM TEXAS TECH WRF AND HRRR SHOWED
AREAS OF CONVECTION INCREASING OVER THE COASTAL WATERS LATER TONIGHT
INTO WEDNESDAY. RAISED POPS TO LIKELY CATEGORY FOR THE OFFSHORE
WATERS LATE TONIGHT THROUGH WEDNESDAY. NORTHEAST WINDS MAY APPROACH
SCEC LEVELS OVER THE GULF WATERS ON WEDNESDAY.
&&
.PREV DISCUSSION... /ISSUED 636 PM CDT TUE AUG 26 2014/
DISCUSSION...UPDATED FOR 00Z AVIATION.
AVIATION...SHOWERS MAINLY ENDING THIS EVENING...BUT HAVE A FEW
REMAINING BETWEEN ALI AND COT. THESE WILL NOT AFFECT TAF SITES FOR
THE REST OF TONIGHT. OVERNIGHT SHOULD HAVE MAINLY VFR
CONDITIONS...WILL SEE SOME LOW LEVEL CU DEVELOP...BUT DONT EXPECT
A CIG CONDITION. WITH MORE MOISTURE BUILDING IN AND AN APPROACHING
UPPER DISTURBANCE...WILL CONTINUE SHOWER/STORM CHANCES TOMORROW
FOR CRP/VCT TAF SITES. ALI WOULD HAVE SMALLER CHANCE...TOO SMALL
TO INCLUDE IN TAFS THIS SOON.
PREV DISCUSSION... /ISSUED 352 PM CDT TUE AUG 26 2014/
SHORT TERM (TONIGHT THROUGH WEDNESDAY NIGHT)...EXPECTING ACTIVITY
OVER INLAND AREAS TO END AROUND OR BEFORE SUNSET...WITH ACTIVITY
PICKING UP AGAIN OVER THE EASTERN AREAS/GULF WATERS OVERNIGHT.
HOWEVER...ACTIVITY MAY LINGER A BIT MORE OVER THE NORTHEAST BUT
SHOULD EVENTUALLY DIE OFF BEFORE MIDNIGHT...WITH SHOWERS
DEVELOPING OVER THE GULF WATERS OVERNIGHT. THEN...SHOULD BE SEEING
AN INCREASE IN CONVECTION SPREADING FARTHER INLAND ON
WEDNESDAY...WITH THE BETTER CHANCES MORE TOWARD THE NORTHEAST. AM
GOING TO GO WITH ISOLATED TO SCATTERED CONVECTION AS DO EXPECT
CONVECTION WEDNESDAY OVER MOST INLAND AREAS (OBVIOUSLY THE
SCATTERED CONVECTION CLOSER TO THE COAST AND ISOLATED FARTHER
WEST). WILL LIKELY HAVE A BRIEF LULL IN CONVECTION IN THE
EVENING...THEN START UP AGAIN DURING THE LATE EVENING/OVERNIGHT
HOURS WEDNESDAY NIGHT OVER THE COASTAL AREAS. WITH INCREASE IN
MOISTURE...SHOULD SEE A SLIGHT WARM-UP IN OVERNIGHT LOWS TONIGHT
AND WEDNESDAY NIGHT...BUT COOLER TEMPERATURES WEDNESDAY DUE TO
CLOUDS AND RAIN-COOLED AREAS.
MARINE (TONIGHT THROUGH WEDNESDAY NIGHT)...BELOW SCEC CONDITIONS
EXPECTED THROUGH THE PERIOD. SCATTERED SHOWERS/THUNDERSTORMS
BECOME MORE PREVALENT THROUGH THE PERIOD...AS THE TROUGH
APPROACHES THE AREA BRINGING IN DEEPER TROPICAL MOISTURE. WINDS AND
SEAS HIGHER IN THUNDERSTORMS.
LONG TERM (THURSDAY THROUGH TUESDAY)...WITH RESPECT TO THE GFS
ENSEMBLE MEAN...THE UPPER TROUGH/LOW IS EXPECTED TO MEANDER OVER THE
CWA/MSA THURSDAY THEN DISSIPATE FRIDAY AS A PROGRESSIVE SYSTEM
MOVES ACRS THE SRN PLAINS/NRN AND CNTRL TX. SELECT GFS DETERMINISTIC
SOUNDINGS SUGGEST COPIOUS MSTR/VERY HIGH PWAT VALUES OVER THE
CWA/MSA THURSDAY THROUGH SUNDAY. YET...GFS ENSEMBLE MEAN SUGGEST
THAT AN UPPER RIDGE WILL BUILD OVER THE CWA/MSA BEGINNING SUNDAY/
MONDAY. THUS...EXPECT SCT CONVECTION OVER THE CWA/MSA (OWING TO
COPIOUS MSTR AND TO UPPER/SFC FORCING) WITH LOCALLY HEAVY RAINFALL
(EFFICIENT RAINFALL PRODUCTION) THURSDAY/FRIDAY...A DECREASE IN
COVERAGE SATURDAY/SUNDAY...AND NO PCPN MONDAY/TUESDAY. ANTICIPATE
LOWER MAX TEMPS THURSDAY THROUGH SATURDAY WITH A STEADY INCREASE
AFTERWARD. ANTICIPATE MAX HEAT INDEX VALUES 105-109F MONDAY/TUESDAY.
&&
.PRELIMINARY POINT TEMPS/POPS...
CORPUS CHRISTI 77 95 78 91 78 / 20 40 30 40 30
VICTORIA 76 95 77 92 76 / 20 50 30 40 30
LAREDO 79 102 80 100 80 / 10 10 10 20 20
ALICE 75 98 76 95 77 / 10 30 20 30 30
ROCKPORT 79 91 80 88 80 / 20 50 40 40 30
COTULLA 76 100 76 100 76 / 10 10 10 20 20
KINGSVILLE 75 97 76 94 77 / 10 40 20 40 30
NAVY CORPUS 80 90 81 87 80 / 20 50 40 40 30
&&
.CRP WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
GM...NONE.
&&
$$
TMT/89...SHORT TERM
AREA FORECAST DISCUSSION
NWS FORT WORTH TX
333 PM CDT MON AUG 25 2014
.DISCUSSION...
IT IS A QUIET AND WARM DAY ACROSS THE REGION AS WE AWAIT OUR NEXT
WEATHER SYSTEMS. THE UPPER LEVEL RIDGE THAT HAS BEEN DOMINATING OUR
WEATHER PATTERN THE LAST FEW DAYS HAS MOVED TO OUR NORTHEAST AND WILL
REMAIN CENTERED TO OUR NORTHEAST AS A TUTT LOW IN THE NORTHERN
GULF OF MEXICO MOVES WEST TOWARDS THE TEXAS COAST. THIS FEATURE IS
SCHEDULED BY MOST OF THE MODELS TO APPROACH THE TEXAS COAST
TUESDAY AFTERNOON BUT THE RAP IS INDICATING A MUCH SLOWER MOVEMENT
OF THE TUTT. IN ADDITION...THE TRACK OF THE TUTT APPEARS TO BE
SLIGHTLY FURTHER SOUTH THAN PREVIOUS MODEL RUNS. DESPITE
THIS...RICH TROPICAL MOISTURE WILL STILL MOVE WEST AND NORTHWEST
INTO THE REGION STARTING TUESDAY AND THE UPPER LEVEL RIDGE WILL
WEAKEN SOME OVER THE REGION. THIS WILL ALLOW ISOLATED TO SCATTERED
CONVECTION TO DEVELOP ACROSS THE REGION TOMORROW AFTERNOON.
COVERAGE IS NOT EXPECTED TO BE VERY HIGH SO KEPT RAIN CHANCES AT
20 PERCENT ACROSS THE EAST AND SOUTHEAST WITH JUST AN ISOLATED
MENTION ELSEWHERE. GUSTY WINDS...LIGHTNING AND BRIEF HEAVY RAIN
WILL BE POSSIBLE WITH ANY THUNDERSTORMS.
ON WEDNESDAY...WE WILL REMAIN IN A TRANSITION PERIOD AS AN UPPER
LEVEL TROUGH MOVES ACROSS THE WESTERN CONUS. THIS TROUGH WILL HELP
TO FURTHER PUSH THE RIDGE TO THE EAST. ISOLATED TO SCATTERED
CONVECTION WILL BE POSSIBLE ON WEDNESDAY AS RICH ATMOSPHERIC
MOISTURE REMAINS IN PLACE. ON THURSDAY THE UPPER LEVEL TROUGH
MOVES INTO THE PLAINS. PREVIOUS MODEL RUNS WERE IN DECENT
AGREEMENT ON THE SPEED OF THE TROUGH BUT THE LATEST RUNS HAVE
AGAIN STARTED TO DIVERGE FROM EACH OTHER. AS THE TROUGH APPROACHES
FROM THE WEST ON THURSDAY...ISOLATED TO SCATTERED CONVECTION WILL
AGAIN OCCUR IN THE AFTERNOON AND EVENING HOURS WITH BETTER
COVERAGE LIKELY IN THE SOUTHEAST WHERE THE MOISTURE WILL BE
HIGHER...AND IN THE NORTHWEST CLOSER TO THE APPROACHING TROUGH.
OUR BEST RAIN CHANCES WILL BE FRIDAY AND/OR SATURDAY DEPENDING ON
THE SPEED OF THE TROUGH. THE GFS IS THE FASTEST OF THE EXTENDED
MODELS WITH THE ECMWF THE SLOWEST OF THE MODELS. BECAUSE OF THE
DISCREPANCIES...HAVE LINGERED POPS INTO SUNDAY AND ENDED THEM
FROM WEST TO EAST THROUGH THE DAY. IF THE GFS IS REALIZED AND THE
TROUGH IS OFF TO OUR NORTHEAST BY SATURDAY NIGHT...THE RAIN
CHANCES WILL END EARLIER. BENEFICIAL RAIN IS POSSIBLE WITH THIS
SYSTEM DEPENDING ON THE SPEED OF THE UPPER LEVEL TROUGH BUT SOME
LOCATIONS WILL BENEFIT FROM THE RAIN MORE THAN OTHERS.
WITH THE PATTERN CHANGE THIS WEEK...TEMPERATURES THROUGH MIDWEEK
WILL BE SLIGHTLY ABOVE NORMAL BUT BELOW 100 DEGREES. FOR THE
LATTER HALF OF THE WEEK...EXPECT NEAR OR SLIGHTLY BELOW NORMAL
TEMPERATURES.
82/JLD
&&
.AVIATION...
/ISSUED 1257 PM CDT MON AUG 25 2014/
FOR THE 18Z TAFS...VFR CONDITIONS ARE EXPECTED THROUGH THE VALID
FORECAST PERIOD. THUNDERSTORM CHANCES AROUND AREA TAF SITES
TOMORROW AFTERNOON IS THE PRIMARY AVIATION WEATHER CONCERN.
IN THE SHORT TERM...LIGHT SOUTHWESTERLY WINDS ARE EXPECTED TO
BECOME SOUTHEASTERLY BY 20Z. FORECAST SOUNDINGS AND MORNING
AIRCRAFT RAOBS INDICATED THAT HEATING TODAY WAS UNLIKELY TO BREAK
THE CAP IN PLACE OVER THE REGION. THEREFORE DRY CONDITIONS ARE
EXPECTED OVER THE NEXT 18 HOURS. BY TOMORROW AFTERNOON...18-24
HOURS OF SOUTHEASTERLY WINDS SHOULD BRING DEEPER MOISTURE INTO THE
REGION WHICH WILL ALLOW FOR ISOLATED TO SCATTERED THUNDERSTORMS TO
DEVELOP ACROSS THE REGION DURING THE PEAK HEATING HOURS OF THE DAY
TOMORROW AFTERNOON. WENT AHEAD WITH A MENTION OF VCTS AT THE END
OF THE DFW TAF TO ACCOUNT FOR THIS POSSIBILITY. CONFIDENCE IS HIGH
THAT A STORM WILL DIRECTLY IMPACT A TAF SITE...BUT MOST FORECAST
SOUNDINGS INDICATED LITTLE CAP IN PLACE OVER THE REGION BY 21Z
TOMORROW.
CAVANAUGH
&&
.PRELIMINARY POINT TEMPS/POPS...
DALLAS-FT. WORTH, TX 79 98 77 98 77 / 5 10 10 10 10
WACO, TX 75 98 74 98 74 / 5 10 10 10 10
PARIS, TX 73 95 72 95 71 / 5 20 20 10 10
DENTON, TX 76 97 74 97 73 / 5 10 10 10 10
MCKINNEY, TX 75 96 74 96 72 / 5 10 10 10 10
DALLAS, TX 80 98 78 98 77 / 5 10 10 10 10
TERRELL, TX 77 98 76 97 74 / 5 20 20 10 10
CORSICANA, TX 77 98 76 97 74 / 5 20 20 20 20
TEMPLE, TX 74 99 74 98 73 / 5 10 10 20 20
MINERAL WELLS, TX 74 98 73 98 74 / 10 10 10 10 10
&&
.FWD WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
69/82
AREA FORECAST DISCUSSION
NWS FORT WORTH TX
1257 PM CDT MON AUG 25 2014
.AVIATION...
FOR THE 18Z TAFS...VFR CONDITIONS ARE EXPECTED THROUGH THE VALID
FORECAST PERIOD. THUNDERSTORM CHANCES AROUND AREA TAF SITES
TOMORROW AFTERNOON IS THE PRIMARY AVIATION WEATHER CONCERN.
IN THE SHORT TERM...LIGHT SOUTHWESTERLY WINDS ARE EXPECTED TO
BECOME SOUTHEASTERLY BY 20Z. FORECAST SOUNDINGS AND MORNING
AIRCRAFT RAOBS INDICATED THAT HEATING TODAY WAS UNLIKELY TO BREAK
THE CAP IN PLACE OVER THE REGION. THEREFORE DRY CONDITIONS ARE
EXPECTED OVER THE NEXT 18 HOURS. BY TOMORROW AFTERNOON...18-24
HOURS OF SOUTHEASTERLY WINDS SHOULD BRING DEEPER MOISTURE INTO THE
REGION WHICH WILL ALLOW FOR ISOLATED TO SCATTERED THUNDERSTORMS TO
DEVELOP ACROSS THE REGION DURING THE PEAK HEATING HOURS OF THE DAY
TOMORROW AFTERNOON. WENT AHEAD WITH A MENTION OF VCTS AT THE END
OF THE DFW TAF TO ACCOUNT FOR THIS POSSIBILITY. CONFIDENCE IS HIGH
THAT A STORM WILL DIRECTLY IMPACT A TAF SITE...BUT MOST FORECAST
SOUNDINGS INDICATED LITTLE CAP IN PLACE OVER THE REGION BY 21Z
TOMORROW.
CAVANAUGH
&&
.UPDATE...
THE UPPER LEVEL RIDGE WILL CONTINUE TO CONTROL THE WEATHER
RESULTING IN A HOT DAY ACROSS THE REGION UNDER CLEAR OR MOSTLY
CLEAR SKIES WITH LIGHT WINDS. FORECAST MODELS INDICATE THE
PRECIPITATION THAT CONTINUES IN THE TEXAS PANHANDLE IS OCCURRING
WITHIN A SHEAR AXIS THAT WILL CONTINUE TO SLIDE EAST-NORTHEAST
TODAY. THE HRRR DEVELOPS ISOLATED CONVECTION IN OUR FAR
NORTHWESTERN COUNTIES THIS AFTERNOON...NEAR THIS SHEAR AXIS BUT AS
OF NOW IT IS THE ONLY MODEL DEVELOPING CONVECTION IN THE AREA.
FORECAST MODEL SOUNDINGS IN THAT AREA INDICATE A DRY ATMOSPHERE IN
PLACE THROUGH THE REGION AND AM NOT INCLINED TO ADD POPS AT THIS
TIME BUT WILL INCLUDE SILENT 10 POPS AND WATCH TRENDS THROUGH THE
AFTERNOON HOURS. OTHERWISE...THE FORECAST WAS ON TRACK AND NO
SIGNIFICANT CHANGES WERE NEEDED FOR THE UPDATE.
82/JLD
&&
.PREV DISCUSSION... /ISSUED 347 AM CDT MON AUG 25 2014/
THE UPPER LEVEL HIGH THAT BROUGHT US OUR LATEST STRETCH OF HOT AND
DRY WEATHER WILL BEGIN TO WEAKEN AND BACK OFF TO THE NORTHEAST
TODAY AND TOMORROW. SURFACE WINDS WILL BE FAIRLY LIGHT TODAY WHICH
MEANS HIGH TEMPS WILL BE A LITTLE WARMER THAN YESTERDAY. ALSO LOW
TEMPS IN NON-URBAN AREAS WILL COOL OFF A LITTLE MORE TONIGHT
COMPLIMENTS OF THE LIGHT WINDS AND CLEAR SKIES.
THE LATEST WATER VAPOR LOOP SHOWS THE WEAK TUTT LOW THAT WE HAVE
BEEN TRACKING FOR THE LAST FEW DAYS HAS MOVED WEST INTO THE
CENTRAL GULF. MEANWHILE A NON-TROPICAL SURFACE LOW CENTER HAS
DEVELOPED NEAR THE MISSISSIPPI RIVER DELTA ALONG AN OLD FRONTAL
BOUNDARY THAT HAS PUSHED INTO THE NORTHEAST GULF OF MEXICO. THE
TUTT AND SURFACE LOW WILL CONTINUE ON A WESTERLY TRACK...WITH THE
UPPER TUTT AXIS CROSSING OUR CWA TUESDAY AND CAUSING PRECIPITABLE
WATER VALUES TO SURGE TO NEAR 2 INCHES. THE BETTER CHANCES OF RAIN
WILL BE OVER THE EASTERN AND SOUTHEASTERN ZONES TUESDAY AFTERNOON
AND EVENING WHERE LIFT/MOISTURE ARE GREATER. HOWEVER WILL MENTION
ISOLATED SHOWERS/STORMS IN THE FORECAST ALONG AND WEST OF THE I-35
CORRIDOR AS THERE IS SOME SPATTERING OF QPF FROM SEVERAL MODELS
THERE AS WELL. LOW LEVEL WINDS WILL BECOME EASTERLY DURING THE DAY
TUESDAY AND WE WILL SEE THE BEGINNING OF A SLIGHT COOLING TREND
IN HIGH TEMPS AS LOW LEVEL THICKNESSES DECREASE FROM EAST TO WEST.
THE SURFACE LOW WILL HANG OUT IN THE WESTERN GULF INTO THURSDAY...
AND WHILE TROPICAL DEVELOPMENT OF THIS FEATURE IS NOT LIKELY...IT
WILL TEND TO CONSOLIDATE THE BETTER MOISTURE/CONVECTION OVER THE
WESTERN GULF AND SOUTH TEXAS. NORTH TEXAS WILL SEE DRY ADVECTION
DUE TO PERSISTENT EASTERLY FETCH IN THE LOW LEVELS AROUND THIS
CYCLONE...AND THUS HAVE LOWERED POPS TO 10 PERCENT. WILL RETAIN A
MENTION OF AFTERNOON/EVENING ISOLATED CONVECTION IN THE WORDED
FORECAST AS MOISTURE AND INSTABILITY STILL SHOULD BE SUFFICIENT
FOR SUCH ON WEDNESDAY. MOISTURE DIMINISHES EVEN MORE INTO
THURSDAY...AND THUS WILL SHOW A DRY FORECAST EXCEPT FOR THE
SOUTHEAST ZONES. MOST OF THE RAIN ACTIVITY WILL REMAIN TO OUR
SOUTH AND EAST WHERE PRECIPITABLE WATERS STAY ABOVE 2 INCHES WITH
THE GULF LOW PRESSURE SYSTEM.
FORTUNATELY...AFTER SEVERAL DAYS OF MODEL DISAGREEMENT...GUIDANCE
HAS COME INTO EXCELLENT AGREEMENT REGARDING THE TRACK AND SPEED OF
A LONGWAVE TROUGH THAT MOVES EAST ACROSS THE CONUS. AS THIS SYSTEM
APPROACHES THE REGION THURSDAY AND FRIDAY...IT WILL DRAW THE RICH
GULF MOISTURE NORTHWESTWARD INTO THE REGION. RAIN CHANCES WILL
INCREASE FRIDAY AND INTO SATURDAY AS UPPER LEVEL FORCING FROM THE
TROUGH INTERACTS WITH THIS HIGH MOISTURE AND INSTABILITY. LIFT
FROM THE UPPER TROUGH LOOKS FAIRLY STRONG FOR THE TIME OF THE
YEAR...AND SHEAR MAY BE MARGINALLY SUFFICIENT FOR MULTICELL
CONVECTIVE MODES WITH A THREAT FOR SOME SEVERE STORMS. HIGH
PRECIPITABLE WATER AND INSTABILITY WILL CERTAINLY SUPPORT A
LOCALLY HEAVY RAIN THREAT. HAVE BUMPED UP POPS TO 30 PERCENT FOR
MOST OF THE AREA FRIDAY NIGHT AND SATURDAY...AND THESE POPS WILL
PROBABLY BE RAISED FURTHER AS CONFIDENCE IN THE TIMING OF THE
UPPER TROUGH INCREASES. RAIN CHANCES SHOULD DIMINISH SUNDAY FROM
WEST TO EAST WITH THE PASSAGE OF THE UPPER TROUGH AXIS.
TEMPERATURES WILL COOL INTO THE LOW TO MID 90S FRIDAY AND SATURDAY
DUE TO THE INCREASED CLOUDS AND MOISTURE. TEMPS REBOUND ONLY
SLIGHTLY SUNDAY AND MONDAY AS GEOPOTENTIAL HEIGHTS REMAIN
DEPRESSED IN THE WAKE OF THE UPPER TROUGH.
TR.92
&&
.PRELIMINARY POINT TEMPS/POPS...
DALLAS-FT. WORTH, TX 101 78 99 78 98 / 5 5 10 10 10
WACO, TX 101 75 99 74 98 / 5 5 10 20 10
PARIS, TX 97 75 95 73 95 / 5 5 20 20 10
DENTON, TX 100 75 98 74 97 / 5 5 10 10 10
MCKINNEY, TX 99 75 97 74 96 / 5 5 10 10 10
DALLAS, TX 100 80 99 79 98 / 5 5 10 10 10
TERRELL, TX 100 77 98 75 97 / 5 5 20 20 10
CORSICANA, TX 100 76 98 75 97 / 5 5 20 20 20
TEMPLE, TX 100 74 99 73 98 / 5 5 10 20 20
MINERAL WELLS, TX 102 74 100 73 98 / 10 10 5 10 10
&&
.FWD WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
/
AREA FORECAST DISCUSSION...UPDATED
NWS FORT WORTH TX
1148 AM CDT MON AUG 25 2014
.UPDATE...
THE UPPER LEVEL RIDGE WILL CONTINUE TO CONTROL THE WEATHER
RESULTING IN A HOT DAY ACROSS THE REGION UNDER CLEAR OR MOSTLY
CLEAR SKIES WITH LIGHT WINDS. FORECAST MODELS INDICATE THE
PRECIPITATION THAT CONTINUES IN THE TEXAS PANHANDLE IS OCCURRING
WITHIN A SHEAR AXIS THAT WILL CONTINUE TO SLIDE EAST-NORTHEAST
TODAY. THE HRRR DEVELOPS ISOLATED CONVECTION IN OUR FAR
NORTHWESTERN COUNTIES THIS AFTERNOON...NEAR THIS SHEAR AXIS BUT AS
OF NOW IT IS THE ONLY MODEL DEVELOPING CONVECTION IN THE AREA.
FORECAST MODEL SOUNDINGS IN THAT AREA INDICATE A DRY ATMOSPHERE IN
PLACE THROUGH THE REGION AND AM NOT INCLINED TO ADD POPS AT THIS
TIME BUT WILL INCLUDE SILENT 10 POPS AND WATCH TRENDS THROUGH THE
AFTERNOON HOURS. OTHERWISE...THE FORECAST WAS ON TRACK AND NO
SIGNIFICANT CHANGES WERE NEEDED FOR THE UPDATE.
82/JLD
&&
.AVIATION...
/ISSUED 638 AM CDT MON AUG 25 2014/
CONCERNS...NONE.
SURFACE HIGH PRESSURE TO THE EAST-NORTHEAST WILL BE LOOSENING ITS
GRIP ON THE REGION WHILE A SURFACE TROUGH REMAINS WILL REMAIN
ACROSS THE PANHANDLE AND WEST TEXAS REGION. THIS WILL CAUSE WINDS
TO BACK TO THE SOUTHEAST LATE THIS AFTERNOON AND REMAIN SO OVERNIGHT.
COULD SEE A SOUTHWEST COMPONENT FOR A FEW HOURS THIS MORNING.
ALL TERMINALS WILL BE VFR WITH SOUTHERLY WINDS LESS THAN 10 KNOTS
TODAY AND SOUTHEASTERLY WINDS LESS THAN 8 KNOTS TONIGHT. 75
&&
.PREV DISCUSSION... /ISSUED 347 AM CDT MON AUG 25 2014/
THE UPPER LEVEL HIGH THAT BROUGHT US OUR LATEST STRETCH OF HOT AND
DRY WEATHER WILL BEGIN TO WEAKEN AND BACK OFF TO THE NORTHEAST
TODAY AND TOMORROW. SURFACE WINDS WILL BE FAIRLY LIGHT TODAY WHICH
MEANS HIGH TEMPS WILL BE A LITTLE WARMER THAN YESTERDAY. ALSO LOW
TEMPS IN NON-URBAN AREAS WILL COOL OFF A LITTLE MORE TONIGHT
COMPLIMENTS OF THE LIGHT WINDS AND CLEAR SKIES.
THE LATEST WATER VAPOR LOOP SHOWS THE WEAK TUTT LOW THAT WE HAVE
BEEN TRACKING FOR THE LAST FEW DAYS HAS MOVED WEST INTO THE
CENTRAL GULF. MEANWHILE A NON-TROPICAL SURFACE LOW CENTER HAS
DEVELOPED NEAR THE MISSISSIPPI RIVER DELTA ALONG AN OLD FRONTAL
BOUNDARY THAT HAS PUSHED INTO THE NORTHEAST GULF OF MEXICO. THE
TUTT AND SURFACE LOW WILL CONTINUE ON A WESTERLY TRACK...WITH THE
UPPER TUTT AXIS CROSSING OUR CWA TUESDAY AND CAUSING PRECIPITABLE
WATER VALUES TO SURGE TO NEAR 2 INCHES. THE BETTER CHANCES OF RAIN
WILL BE OVER THE EASTERN AND SOUTHEASTERN ZONES TUESDAY AFTERNOON
AND EVENING WHERE LIFT/MOISTURE ARE GREATER. HOWEVER WILL MENTION
ISOLATED SHOWERS/STORMS IN THE FORECAST ALONG AND WEST OF THE I-35
CORRIDOR AS THERE IS SOME SPATTERING OF QPF FROM SEVERAL MODELS
THERE AS WELL. LOW LEVEL WINDS WILL BECOME EASTERLY DURING THE DAY
TUESDAY AND WE WILL SEE THE BEGINNING OF A SLIGHT COOLING TREND
IN HIGH TEMPS AS LOW LEVEL THICKNESSES DECREASE FROM EAST TO WEST.
THE SURFACE LOW WILL HANG OUT IN THE WESTERN GULF INTO THURSDAY...
AND WHILE TROPICAL DEVELOPMENT OF THIS FEATURE IS NOT LIKELY...IT
WILL TEND TO CONSOLIDATE THE BETTER MOISTURE/CONVECTION OVER THE
WESTERN GULF AND SOUTH TEXAS. NORTH TEXAS WILL SEE DRY ADVECTION
DUE TO PERSISTENT EASTERLY FETCH IN THE LOW LEVELS AROUND THIS
CYCLONE...AND THUS HAVE LOWERED POPS TO 10 PERCENT. WILL RETAIN A
MENTION OF AFTERNOON/EVENING ISOLATED CONVECTION IN THE WORDED
FORECAST AS MOISTURE AND INSTABILITY STILL SHOULD BE SUFFICIENT
FOR SUCH ON WEDNESDAY. MOISTURE DIMINISHES EVEN MORE INTO
THURSDAY...AND THUS WILL SHOW A DRY FORECAST EXCEPT FOR THE
SOUTHEAST ZONES. MOST OF THE RAIN ACTIVITY WILL REMAIN TO OUR
SOUTH AND EAST WHERE PRECIPITABLE WATERS STAY ABOVE 2 INCHES WITH
THE GULF LOW PRESSURE SYSTEM.
FORTUNATELY...AFTER SEVERAL DAYS OF MODEL DISAGREEMENT...GUIDANCE
HAS COME INTO EXCELLENT AGREEMENT REGARDING THE TRACK AND SPEED OF
A LONGWAVE TROUGH THAT MOVES EAST ACROSS THE CONUS. AS THIS SYSTEM
APPROACHES THE REGION THURSDAY AND FRIDAY...IT WILL DRAW THE RICH
GULF MOISTURE NORTHWESTWARD INTO THE REGION. RAIN CHANCES WILL
INCREASE FRIDAY AND INTO SATURDAY AS UPPER LEVEL FORCING FROM THE
TROUGH INTERACTS WITH THIS HIGH MOISTURE AND INSTABILITY. LIFT
FROM THE UPPER TROUGH LOOKS FAIRLY STRONG FOR THE TIME OF THE
YEAR...AND SHEAR MAY BE MARGINALLY SUFFICIENT FOR MULTICELL
CONVECTIVE MODES WITH A THREAT FOR SOME SEVERE STORMS. HIGH
PRECIPITABLE WATER AND INSTABILITY WILL CERTAINLY SUPPORT A
LOCALLY HEAVY RAIN THREAT. HAVE BUMPED UP POPS TO 30 PERCENT FOR
MOST OF THE AREA FRIDAY NIGHT AND SATURDAY...AND THESE POPS WILL
PROBABLY BE RAISED FURTHER AS CONFIDENCE IN THE TIMING OF THE
UPPER TROUGH INCREASES. RAIN CHANCES SHOULD DIMINISH SUNDAY FROM
WEST TO EAST WITH THE PASSAGE OF THE UPPER TROUGH AXIS.
TEMPERATURES WILL COOL INTO THE LOW TO MID 90S FRIDAY AND SATURDAY
DUE TO THE INCREASED CLOUDS AND MOISTURE. TEMPS REBOUND ONLY
SLIGHTLY SUNDAY AND MONDAY AS GEOPOTENTIAL HEIGHTS REMAIN
DEPRESSED IN THE WAKE OF THE UPPER TROUGH.
TR.92
&&
.PRELIMINARY POINT TEMPS/POPS...
DALLAS-FT. WORTH, TX 101 78 99 78 98 / 5 5 10 10 10
WACO, TX 101 75 99 74 98 / 5 5 10 20 10
PARIS, TX 97 75 95 73 95 / 5 5 20 20 10
DENTON, TX 100 75 98 74 97 / 5 5 10 10 10
MCKINNEY, TX 99 75 97 74 96 / 5 5 10 10 10
DALLAS, TX 100 80 99 79 98 / 5 5 10 10 10
TERRELL, TX 100 77 98 75 97 / 5 5 20 20 10
CORSICANA, TX 100 76 98 75 97 / 5 5 20 20 20
TEMPLE, TX 100 74 99 73 98 / 5 5 10 20 20
MINERAL WELLS, TX 102 74 100 73 98 / 10 10 5 10 10
&&
.FWD WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
69/82
AREA FORECAST DISCUSSION
NWS LUBBOCK TX
1133 PM CDT SUN AUG 24 2014
.AVIATION...
VFR CONDITIONS SHOULD PREVAIL FOR THE NEXT 24 HOURS. TSRA ACTIVITY
IS EXPECTED ACROSS THE AREA MONDAY AFTERNOON AND EVENING...BUT WILL MOST
LIKELY REMAIN WEST OF BOTH TERMINALS. LIGHT EASTERLY SURFACE WINDS
EARLY THIS MORNING SHOULD BECOME SOUTHERLY BUT REMAIN AROUND 12
KTS OR LESS DURING THE DAY.
&&
.PREV DISCUSSION... /ISSUED 725 PM CDT SUN AUG 24 2014/
UPDATE...
QUICK UPDATE TO ADJUST POP/WX/QPF GRIDS THROUGH THIS EVENING TO
BETTER CORRESPOND TO CURRENT RADAR TRENDS. MOST NOTABLY...
INCREASED POPS INTO THE CHANCE AND LIKELY CATEGORIES ACROSS A GOOD
PORTION OF THE ROLLING PLAINS WHERE A POORLY ORGANIZED CLUSTER OF
CONVECTION CONTINUES. WE EXPECT AN OVERALL DOWNWARD TREND IN THE
CONVECTION THROUGH THE MID/LATE EVENING HOURS AS THE UNSTABLY AND
DIURNALLY DRIVEN FORCING WANES.
PREV DISCUSSION... /ISSUED 636 PM CDT SUN AUG 24 2014/
AVIATION...
CURRENT RADAR TRENDS SUGGEST THAT KLBB AND KCDS MAY ESCAPE ANY
-TSRA IN THE NEXT HOUR OR SO...BUT THERE IS STILL AN OUTSIDE
CHANCE. ALSO...SOME GUSTY OUTFLOW WINDS ARE STILL POSSIBLE.
OTHERWISE...VFR CONDITIONS WITH SRLY SURFACE WINDS EXPECTED
THROUGH MID-AFTERNOON MONDAY.
PREV DISCUSSION... /ISSUED 343 PM CDT SUN AUG 24 2014/
SHORT TERM...
DESPITE OF A WESTWARD EXPANSION OF WEAK RIDGING ALOFT AND VERY
LITTLE IF ANY SURFACE FEATURES...AN ADEQUATE BOOST IN THETA-E EARLIER
TODAY SUPPLIED MUCH OF THE AREA WITH DEEPER MOISTURE NECESSARY FOR
SOME DIURNALLY DRIVEN TSTORMS. NON-HIGH RES MODELS HAVE LARGELY
MISSED THE BOAT SO FAR TODAY WITH THE EXPERIMENTAL MODELS PLAYING
THE ROLE OF THE DARK HORSE. RAP DATA SHOW THE RICHEST PWATS OF 1.3
INCHES CONFINED EAST OF A BROWNFIELD TO SILVERTON LINE WITH
GENERALLY ONE INCH OR LESS FARTHER WEST. ENVIRONMENT IN THE RICHER
PWATS IS CHARACTERIZED BY SBCAPES OF 1200-2500 J/KG WITH WEAK SHEAR.
THIS THEME WILL PERSIST THROUGH MID-EVENING AT WHICH POINT TSTORMS
WILL DWINDLE...BUT UNTIL THEN WE EXPECT ADDITIONAL STRONG TO PERHAPS
BRIEFLY SEVERE PULSE MODES WITH MICROBURSTS THE PRIMARY HAZARD.
BY MONDAY MORNING...DEEPER MONSOONAL MOISTURE WILL BE TUGGED NORTH
INTO NEW MEXICO AROUND THE ZONAL RIDGE AXIS STILL POISED FIRMLY OVER
THE SOUTH PLAINS. HEIGHT FIELDS ON THE WESTERN PERIPHERY OF THIS
RIDGE ARE NOT SHOWN TO BUILD ANY...SO THE OPPORTUNITY WILL EXIST FOR
ANOTHER ROUND OF SOLAR-POWERED TSTORMS MAINLY NEAR THE NM STATE LINE
WHERE OCCASIONAL DISTURBANCES ARE PROGGED TO LIFT NORTH FROM
CHIHUAHUA. OTHERWISE...WE CONTINUE TO SIDE WITH THE WARMER SPECTRUM
OF MOS GUIDANCE FOR BOTH LOWS AND HIGHS GIVEN THE RECENT OBSERVED
TRENDS.
LONG TERM...
COOLER WEATHER IS ON THE WAY AS WELL AS A SHOT FOR RAIN. BUT BEFORE
WE GET THERE...WARM AND DRY WEATHER WILL CONTINUE TO DOMINATE US AS
HIGH PRESSURE TO OUR EAST EXTENDS OVER THE REGION. OUR NORTHWESTERN
ZONES WILL HAVE A BIT OF A REPRIEVE MONDAY NIGHT AS A WEAKNESS
PROPAGATES AROUND THE WESTERN EDGE OF THE RIDGE. THE WEAKNESS MAKES
USE OF A SURFACE TROF LOCATED OVER THE SOUTHWESTERN TX PANHANDLE AND
FIRES SCATTERED CONVECTION IN THAT REGION. CHANCES ARE ONLY SLIGHT
AS THE AVAILABLE MONSOONAL MOISTURE ONLY COVERS A VERY SMALL AREA
WHICH COINCIDES WITH THE SURFACE TROF. BY TUESDAY AND INTO
WEDNESDAY...THE RIDGE TO OUR EAST BUILDS FURTHER WEST INHIBITING
CHANCES FOR ANY RAIN...HOWEVER A LOW AWAITS US OVER THE GREAT BASIN
AND IS READY TO MOVE IN AND DEFEAT THE EVIL RIDGE. WITH THE
EXCEPTION OF THE GFS...MODELS HAVE BEEN IN DECENT AGREEMENT WITH
HANDLING OF THE LOW THE PAST SEVERAL RUNS. THE 12Z RUN YIELDED THE
GFS SLOWING THE EASTWARD PROGRESSION OF THE LOW AND IS MORE IN LINE
WITH THE OTHER MODELS. THE LOW WILL INITIALLY START OFF CLOSED AS IT
MOVES ACROSS THE ROCKIES INTO THE CENTRAL PLAINS DURING WHICH TIME
IT WILL SLOWLY BECOME AN OPEN WAVE. BY LATE WEDNESDAY A COLD FRONT
SHOULD BE KNOCKING ON OUR DOOR. THE TIMING OF THE FRONT IS SOMEWHAT
IN QUESTION WITH TIMINGS RANGING FROM EARLY TO LATE THURSDAY...WITH
THURSDAY MORNING BEING THE TIMING CHOICE FOR THE TIME BEING. RAIN
CHANCES WILL EXIST ALONG THE FRONT...ESPECIALLY AS THE UPPER LEVEL
LOW PUSHES INTO THE REGION. PWATS OVER 1.3 INCHES WILL BE MORE THAN
ENOUGH TO AID IN MODERATE RAINFALL AMOUNTS. RAIN CHANCES WILL BE
HIGHEST THURSDAY NIGHT INTO EARLY FRIDAY AS A JET MAX PUSHES IN FROM
THE WEST ON THE SOUTHEAST SIDE OF THE LOW. AS OF NOW THE JET MAX IS
GREATEST OVER OUR SOUTHEASTERN ZONES. THIS COMBINED WITH A DIFFLUENT
UPPER PATTERN SHOULD BE MORE THAN EFFICIENT IN DEVELOPING PRECIP.
THE LOW WILL HAVE AN EXTENDED VISIT AND REMAIN OVERHEAD THROUGH LATE
SUNDAY BEFORE ZONAL FLOW TAKES OVER. TEMPERATURES WILL BE RELATIVELY
COOL IN THE SENSE OF TEMPS WILL BE AROUND SEASONAL AVERAGES BUT
COOLER THAN THEY WILL BE EARLIER THIS WEEK. DEPENDING ON THE
STRENGTH OF THE FRONT...SOME AREAS SUCH AS THE TEXAS PANHANDLE MAY
SEE BELOW AVERAGE TEMPS AS COOL AIR OVER MT INTO CA WILL BE PUSHED
SOUTHWARD. AS OF THIS AFTERNOON...PARTS OF INTERIOR MT HAVE FAILED
TO REACH INTO THE 50S. AS OF NOW THE COOLEST AIR WITH THE FRONT
LATER THIS WEEK SHOULD STAY TO OUR NORTH WITH THE COOL SIDE OF THE
FORECAST BEING IN THE UPPER 50S.
&&
.PRELIMINARY POINT TEMPS/POPS...
FRIONA 65 92 63 90 62 / 10 20 20 10 10
TULIA 69 95 65 93 64 / 10 10 20 10 10
PLAINVIEW 65 95 64 92 64 / 10 10 10 10 10
LEVELLAND 67 94 65 91 64 / 10 10 20 10 10
LUBBOCK 72 96 68 94 68 / 10 10 10 10 10
DENVER CITY 67 95 65 92 65 / 10 10 10 10 10
BROWNFIELD 66 96 66 93 66 / 10 10 10 10 10
CHILDRESS 73 101 72 98 72 / 20 10 10 10 10
SPUR 70 100 68 96 68 / 20 0 10 0 10
ASPERMONT 75 102 72 99 71 / 60 0 10 0 10
&&
.LUB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
33
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
254 PM CDT MON AUG 25 2014
.SHORT TERM...(THIS EVENING THROUGH WEDNESDAY NIGHT)
ISSUED AT 254 PM CDT MON AUG 25 2014
MAIN FORECAST CONCERN IS WITH THE RAIN CHANCES THROUGH THE PERIOD.
SURFACE ANALYSIS THIS AFTERNOON SUGGESTS THE COLD FRONT IS MAKING
SLOW EASTWARD PROGRESS THROUGH THE WESTERN SECTIONS OF THE
FORECAST AREA. DEW POINTS REMAIN IN THE 70S AHEAD OF THE FRONT BUT
THEN DROP OFF INTO THE 50S ACROSS CENTRAL MINNESOTA. LOCAL AND
REGIONAL RADARS SHOW THE LINE OF STORMS THAT MOVED THROUGH
OVERNIGHT EXTEND FROM SOUTHEAST WISCONSIN INTO EASTERN IOWA AND
ARE STARTING TO INTENSIFY AGAIN.
THE EXPECTATION THROUGH THE REST OF THE AFTERNOON INTO THE EVENING
IS THAT THE ONGOING ACTIVITY WILL CONTINUE TO MOVE AWAY FROM THE
AREA AS THE FRONT PROGRESSES THROUGH THE FORECAST AREA. SOME
ADDITIONAL ACTIVITY FORMING ON THE WESTERN PART OF THE FRONT OVER
THE MISSOURI RIVER VALLEY. THE 25.17Z HRRR SUGGESTS THIS WILL
TRACK INTO CENTRAL IOWA BEFORE DIMINISHING. HOWEVER...CONFIDENCE
IN THIS MODEL OUTPUT IS NOT THAT HIGH. OUTPUT FROM THE 25.15Z
HOP-WRF DOES SUGGEST THIS MAY SURVIVE AND COME ACROSS NORTHEAST
IOWA THIS EVENING AND WILL SHOW SOME SMALL RAIN CHANCES FOR THIS.
ADDITIONAL CONVECTION SHOULD FORM OVERNIGHT ALONG THE COLD FRONT
AS A SHORT WAVE TROUGH COMES OUT OF THE CENTRAL ROCKIES. THE
MOISTURE TRANSPORT INTO THE FRONT DOES NOT LOOK TO BE ALL THAT
STRONG TONIGHT AND AS CANADIAN HIGH PRESSURE BUILDS IN FROM THE
NORTH...THE BULK OF THE RAIN TONIGHT SHOULD REMAIN OVER CENTRAL
AND SOUTHERN IOWA.
THE HIGH WILL GRADUALLY MOVE EAST-SOUTHEAST ACROSS THE UPPER
MIDWEST AND BE OVER THE U.P. OF MICHIGAN BY WEDNESDAY NIGHT. THIS
IS EXPECTED TO KEEP THE FRONT FAR ENOUGH SOUTH THAT MOST OF THE
CONVECTION ALONG IT FROM TUESDAY THROUGH WEDNESDAY SHOULD STAY TO
THE SOUTH. CANNOT RULE OUT THE SOUTHERN PARTS OF THE FORECAST AREA
GETTING CAUGHT ON THE NORTH EDGE OF THE COMPLEXES THAT FORM ALONG
THE FRONT AND WILL SHOW SOME 20 TO 40 PERCENT RAIN CHANCES FOR
THIS SCENARIO.
BY WEDNESDAY NIGHT THE HIGH WILL START TO MOVE FARTHER OFF TO THE
EAST ALLOWING DEEPER MOISTURE TO START RETURNING TO THE AREA. THIS
MOISTURE RETURN SHOULD OCCUR AHEAD OF STRONGER SHORT WAVE TROUGH
EJECTING NORTHEAST OUT OF THE CENTRAL ROCKIES. THIS WAVE SHOULD
BRING AT LEAST SOME WEAK PV ADVECTION IN THE 500-300 MB LAYER INTO
THE AREA ALONG WITH 1 TO 3 UBAR/S OF UP GLIDE ON THE 310K
ISENTROPIC SURFACE. SHOULD SEE ACTIVITY DEVELOP TO THE
WEST/SOUTHWEST OF THE AREA WEDNESDAY EVENING AND THEN MOVE IN
DURING THE OVERNIGHT HOURS.
.LONG TERM...(THURSDAY THROUGH MONDAY)
ISSUED AT 254 PM CDT MON AUG 25 2014
THE SHORT WAVE TROUGH THAT COMES OUT WEDNESDAY NIGHT WILL TRACK
ACROSS THE UPPER MIDWEST THURSDAY AND SHOULD BE THE FIRST OF
SEVERAL WAVES AS THE MEAN LONG WAVE TROUGH SLOWLY MOVES EAST AS IT
BUMPS INTO THE RIDGING OVER THE EASTERN CONUS. DIFFERENCES BETWEEN
THE 25.12Z ECMWF AND GFS ON HOW FAST THE LONG WAVE TROUGH WILL
MOVE EAST WITH THE ECMWF BEING SLOWER THAN THE GFS. ALSO
DIFFERENCES ON HOW MUCH RIDGING WILL OCCUR BEHIND THIS LONG WAVE
TROUGH AHEAD OF THE NEXT SYSTEM MOVING ONTO THE PACIFIC NORTHWEST
COAST. WITH SUCH DIFFERENCES BETWEEN THE MODELS PLAN TO STAY WITH
THE MODEL CONSENSUS GRIDS AND SHOW RAIN CHANCES THROUGH MUCH OF
THE PERIOD WITH THE HIGHEST CHANCES THURSDAY AND THURSDAY NIGHT AS
THE FIRST SHORT WAVE TROUGH COMES ACROSS THE REGION.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON)
ISSUED AT 1258 PM CDT MON AUG 25 2014
VFR CONDITIONS ARE EXPECTED THROUGH THE FORECAST PERIOD. A COLD
FRONT WILL PUSH SOUTH AND EAST OF THE TAF SITES LATE THIS
AFTERNOON INTO THIS EVENING. THE FRONT LOOKS TO STALL OVER
PORTIONS OF CENTRAL OR NORTHERN IOWA INTO CENTRAL ILLINOIS AND
WILL BE THE FOCUS FOR SHOWERS AND STORMS. THIS ACTIVITY WILL
REMAIN SOUTH OF THE TAF SITES THE NEXT FEW DAYS AS HIGH PRESSURE
BUILDS IN. PLAN ON MID TO HIGH CLOUDS PUSHING NORTH OF THE SHOWER
AND STORM ACTIVITY THIS EVENING INTO THE OVERNIGHT HOURS.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...04
LONG TERM...04
AVIATION...WETENKAMP
FORECAST DISCUSSION FOR ROUTINE AFTERNOON FORECAST ISSUANCE
.SHORT TERM...TONIGHT AND TUESDAY
ISSUED AT 242 PM CDT MON AUG 25 2014
THE LATEST RAP ANALYSIS AND SATELLITE/RADAR IMAGERY SHOW AN OCCLUDED
LOW PRESSURE OVER LAKE WINNIPEG AND A COLD FRONT SLICING ACROSS
WESTERN LAKE SUPERIOR AND WISCONSIN FROM ABOUT HAYWARD TO LA
CROSSE. AHEAD OF THE FRONT...THE ATMOSPHERE HAS BEEN VERY SLOW TO
DESTABILIZE AS TEMPERATURES REMAIN IN THE UPPER 70S TO LOWER 80S.
STARTING TO SEE SOME MIDDLE 80S POP UP OVER WEST-CENTRAL WISCONSIN
WHERE ML CAPES ARE RISING TO ABOUT 1200 J/KG. STILL SEVERAL MORE
HOURS OF HEATING TO GO THOUGH ESPECIALLY OVER CENTRAL AND EASTERN
WISCONSIN WHERE CONVECTIVE DEBRIS CONTINUES TO HOVER OVERHEAD.
BECAUSE OF THE SLOWER HEATING SO FAR...HAVE REDUCED THE CHANCES OF
SHOWERS AND THUNDERSTORMS FOR THE REST OF THE AFTERNOON INTO THE
ISOLATED RANGE AFTER 21Z. AS THE FRONT MOVES THROUGH...SHOWER AND
THUNDERSTORM CHANCES ARE THE MAIN FORECAST CONCERN.
TONIGHT...THE COLD FRONT WILL SLOWLY SLIDE SOUTHEAST ACROSS
NORTHEAST AND EAST-CENTRAL WISCONSIN DURING THE EVENING BEFORE
EXITING THE LAKE MICHIGAN SHORELINE AROUND 06-08Z. AHEAD OF THE
FRONT...WILL LEAVE AN ISOLATED MENTION OF SHOWERS AND THUNDERSTORMS
OVER NORTHEAST AND EAST-CENTRAL WISCONSIN UNTIL THE FRONT CLEARS THE
AREA. IF TEMPS CAN RISE INTO MIDDLE 80S AHEAD OF THE FRONT...WHICH
SEEMS REASONABLE...ANY STORMS THAT DEVELOP COULD BECOME STRONG AND
PRODUCE STRONG GUSTY WINDS AND HAIL. HOWEVER...THE MESO MODELS ARE
EXTREMELY BEARISH IN PREDICTING THUNDERSTORMS THIS AFTERNOON. AND
WITH THE SLOW DESTABILIZATION SO FAR TODAY...HAVE LOWERED THE
CHANCES OF STORMS. AS INSTABILITY IS LOST THIS EVENING...INTENSITY
OF ANY STORMS SHOULD WANE QUICKLY BY MID-EVENING. COOLER AND DRIER
AIR WILL GRADUALLY MAKE INROADS ACROSS THE FORECAST AREA BEHIND THE
FRONT...BUT WARM AND MUGGY CONDITIONS SHOULD HANG ON FOR MUCH OF THE
NIGHT ACROSS THE EAST. LOWS RANGING FROM THE MIDDLE 50S NORTH TO
MIDDLE 60S SOUTHEAST.
TUESDAY...THE COLD FRONT WILL CONTINUE TO MOVE SOUTH OVER SOUTHEAST
WISCONSIN AND NORTHERN ILLINOIS WHILE CANADIAN HIGH PRESSURE MOVES
INTO THE NORTHWEST GREAT LAKES. MOST AREAS WILL SEE A GOOD DEAL OF
SUNSHINE...THOUGH CU MAY BE A LITTLE MORE PREVALENT OVER N-C
WISCONSIN WHILE HIGH CLOUDS WILL LIKELY REMAIN OVERHEAD OVER CENTRAL
AND EAST-CENTRAL WISCONSIN. TEMPS AND HUMIDITY LEVELS WILL BE
SIGNIFICANTLY LOWER THAN TODAYS READINGS...AND WILL GO WITH HIGHS IN
THE LOWER 70S NORTH TO THE UPPER 70S SOUTH.
.LONG TERM...TUESDAY NIGHT THROUGH MONDAY
ISSUED AT 242 PM CDT MON AUG 25 2014
CONTINUED WITH SAME TRENDS OF FORECAST AS MODELS CONTINUE TO SHOW
A PROGRESSIVE NORTHERN STREAM ALONG THE U.S. AND CANADIAN BORDER
THRU THE END OF THE WEEK. WILL BE DEALING WITH ENERGY MOVING
THROUGH THE NORTHERN STREAM AND WEAK CUT OFF TROF MEANDERING OUT
OF THE WEST...THROUGH THE CENTRAL PLAINS.
TUE NIGHT THROUGH THU...EARLY IN PERIOD...SHORT WAVE TO MOVE OUT
OF NORTHERN PLAINS INTO WESTERN LAKES. AT THE SURFACE DRIER AIR
WITH SURFACE HIGH IN PLACE OVER NORTHERN HALF OF WI WITH FRONT SHOVED
SOUTH INTO NORTHERN IL. HAVE CONTINUED DRY FORECAST FROM PREVIOUS
SHIFT...BUT PAST TWO RUNS OF EC SHOWING LIGHT PCPN BREAKING OUT
OVER THE NORTH ALONG 850 FRONT. LATER SHIFT CAN REVIEW BUT FOR NOW
KEPT DRY. MEANDERING TROF BEGINS TO MOVE INTO CENTRAL PLAINS BY THU.
OLD FRONT TO BEGIN TO MAKE WAY NORTH. MODELS SUGGEST CONVECTIVE
COMPLEX DEVELOPING MN/WESTERN WI AS 850 FLOW INCREASES OVER FRONT.
GFS AND NAM FURTHER NORTH WITH COMPLEX THAN CANADIAN AND EC. SREF
TENDING TO SUPPORT FURTHER SOUTH LOOK. HAVE STAYED CLOSE TO
PREVIOUS FORECAST WITH CHANCE POPS DURING DAY ON THU.
UNSETTLED WEATHER TO THEN PERSIST THROUGH THE END OF THE FORECAST
AS MORE ENERGY MOVES THROUGH CANADA.
TEMPERATURES EXPECTED TO RUN NEAR OR A BIT BELOW NORMAL THROUGH
MUCH OF THE PERIOD.
&&
.AVIATION...FOR 18Z TAF ISSUANCE
ISSUED AT 1143 AM CDT MON AUG 25 2014
SHOWERS AND STORMS HAVE EXITED TO THE SOUTH AND EAST BUT
A COLD FRONT STILL RESIDES OVER WESTERN WISCONSIN AND WILL SLOWLY
MOVE EAST OVER THE COURSE OF THE AFTERNOON. ISOLATED OR SCATTERED
SHOWERS AND STORMS ARE POSSIBLE AHEAD OF THE FRONT OVER NORTHEAST
WISCONSIN ONCE THE ATMOSPHERE DESTABILIZES BY LATER THIS AFTERNOON.
DUE TO UNCERTAINTY IN THE COVERAGE OF THESE STORMS...HAVE LEFT OUT A
MENTION AT THE NORTHEAST WISCONSIN TAF SITES. THE FRONT WILL CLEAR
EAST-CENTRAL WISCONSIN LATE IN THE EVENING OR EARLY
OVERNIGHT...ENDING THE SHOWER AND STORM THREAT. DRIER AIR WILL
BUILD INTO THE REGION LATE TONIGHT AND TUESDAY...WHICH SHOULD LEAD
TO GOOD FLYING CONDITIONS.
&&
.GRB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM.....MPC
LONG TERM......TE
AVIATION.......MPC
AREA FORECAST DISCUSSION
NWS GREEN BAY WI
1154 PM CDT SUN AUG 24 2014
UPDATED AVIATION PORTION FOR 06Z TAF ISSUANCE
.SHORT TERM...TONIGHT AND MONDAY
ISSUED AT 243 PM CDT SUN AUG 24 2014
THE LATEST RAP ANALYSIS AND SATELLITE/RADAR IMAGERY SHOW UPPER LEVEL
LOW PRESSURE OVER EASTERN MONTANA AND A DOUBLE BARRELED SURFACE LOW
OVER NORTH DAKOTA. A WARM FRONT EXTENDS FROM THIS SURFACE LOW OVER
SOUTHWEST WISCONSIN...WHICH MARKS THE TRANSITION FROM MOSTLY CLOUDY
SKIES TO CLEAR CONDITIONS. A COLD FRONT EXTENDS SOUTHWARD OVER THE
CENTRAL PLAINS AND IS LARGELY INACTIVE AT THIS HOUR THOUGH THAT
MIGHT BE CHANGING OVER CENTRAL MINNESOTA WHERE ML CAPES HAVE
EXCEEDED 2000 J/KG. A FEW OTHER ELEVATED STORMS CONTINUE TO DEVELOP
OVER NORTHWEST WISCONSIN WITHIN THE TAIL END OF A VORT MAX. WILL
ADD A CHANCE TO N-C WISCONSIN BETWEEN 21Z AND 00Z. AS THE UPPER LOW
AND COLD FRONT MOVE EAST...THUNDERSTORM AND SEVERE WEATHER CHANCES
ARE THE MAIN FORECAST CONCERNS.
TONIGHT...THE LARGE UPPER LOW WILL MOVE ACROSS NORTH DAKOTA INTO THE
LAKE WINNIPEG REGION. MID-LEVEL HEIGHT FALLS FROM THE SYSTEM WILL
MOVE INTO THE WESTERN GREAT LAKES...WHICH WILL HELP PUSH A WEAK COLD
FRONT INTO WESTERN WISCONSIN AFTER MIDNIGHT. CONVERGENCE ALONG THE
FRONT IS RELATIVELY WEAK...BUT ELEVATED INSTABILITY APPROX 1000-1500
J/KG (ROUGH ESTIMATE) WILL MOVE INTO CENTRAL AND NORTH-CENTRAL
WISCONSIN AFTER MIDNIGHT. BECAUSE OF THE WEAK FORCING...KEPT
CHANCES OF PRECIP IN THE SCATTERED RANGE. THE MAGNITUDE OF CAPE AND
WIND SHEAR AROUND 30 KTS WOULD SUPPORT A CHANCE OF STRONG STORMS
THAT COULD PRODUCE NEAR SEVERE HAIL AND WIND GUSTS. WILL LEAVE A
MENTION OF THIS POSSIBILITY IN THE HWO. THE MESO MODELS CONTINUE TO
SHOW CONVECTION DEVELOPING OVER CENTRAL MINNESOTA LATER THIS
AFTERNOON BEFORE TRACKING THE STORMS INTO NORTH-CENTRAL WISCONSIN
AFTER 06Z. THIS STILL SEEMS POSSIBLE BASED ON THE DESTABILIZATION
TAKING PLACE OVER CENTRAL MINNESOTA. THE STORMS SHOULD WEAKEN AS
THEY MOVE EAST LATE TONIGHT DUE TO DIMINISHING INSTABILITY.
OTHERWISE...LOOK FOR A MUGGY EVENING WITH LOWS DROPPING INTO THE
MIDDLE AND UPPER 60S.
MONDAY...THE FRONT WILL MAKE LITTLE PROGRESS TO THE EAST AND INTO
NORTH-CENTRAL WISCONSIN DURING THE AFTERNOON. SPOTTY SHOWERS AND
STORMS WILL BE POSSIBLE AHEAD OF THE FRONT DURING THE MORNING ACROSS
MUCH OF THE AREA. ASSUMING COVERAGE IS NOT MORE THAN
ADVERTISED...LOW LEVEL SOUTHWEST WINDS WILL PUSH TEMPS INTO THE
UPPER 80S OR LOWER 90S OVER THE EASTERN FORECAST AREA. COMBINED
WITH DEWPOINTS AROUND 70 DEGREES...ML CAPES ARE PROJECTED TO REACH
2K-3K J/KG WITH BULK SHEARS AROUND 30 KTS. CONVERGENCE ALONG THE
FRONT WILL REMAIN WEAK BUT CANNOT RULE OUT ISOLATED OR SCATTERED
STRONG TO SEVERE STORMS OVER THE EAST DURING THE AFTERNOON WITH THAN
KIND OF INSTABILITY AND SHEAR. DRIER MID-LEVEL AIR WILL WORK INTO
CENTRAL AND NORTH-CENTRAL WISCONSIN DURING THE AFTERNOON...WHICH
WILL MAKE IT HARDER FOR STORMS TO INITIATE. THE COMBINATION OF HEAT
AND HUMIDITY WILL PUSH HEAT INDICES INTO THE MIDDLE 90S.
.LONG TERM...MONDAY NIGHT THROUGH SUNDAY
ISSUED AT 243 PM CDT SUN AUG 24 2014
MODELS CONTINUE TO INDICATE A RATHER AMPLIFIED MEAN FLOW PATTERN ACROSS
THE CONUS WITH AN UPPER TROF CURRENTLY OVER THE INTER MOUNTAIN
WEST AND SIG RIDGE OVER THE EASTERN LAKES. THE MOVEMENT OF UPPER
LOW OUT OF TROF INTO THE WESTERN LAKES EARLY IN THE PERIOD WILL BE
THE PRIMARY WEATHER FEATURE TO IMPACT OUR WEATHER. BY LATE THIS
WEEK...MODELS CONTINUE TO SHOW LINGERING PIECE OF TROF MEANDERING
INTO THE CENTRAL U.S. THE MOVEMENT OF THIS FEATURE CONTINUES TO
SLOW AS IT REMAINS CUT OFF FROM MAIN BAND OF WESTERLIES EXPECTED
TO LIE OVER SOUTHERN CANADA. FORECAST CONFIDENCE LOW THU NIGHT
ONWARD.
TREND IN SHORTER RANGE IS TO CONTINUE TO SLOW PASSAGE OF COLD
FRONT MONDAY WITH FRONT STILL BISECTING CWA AT 00Z TUE. HAVE
CONTINUE SCATTERED/CHANCE POPS MAINLY SOUTH AND EAST GIVEN
AVAILABLE INSTABILITY. LITTLE DYNAMICS BESIDES FRONT TO SUPPORT
GOING ANY HIGHER WITH POPS.
CONSISTENCY SEEN IN MODELS TO PUSH FRONT AND PCPN MAINLY SOUTH OF
CWA AS HIGH PRESSURE AND DRIER AIR MASS MOVES IN OVER NORTHERN WI
TUE INTO THU. CONCERN THIS PERIOD ON TEMPS. DRIER AIR...SUN AND
LOW LEVEL TEMPS AT OR SLIGHTLY BELOW NORMAL SHOULD SUPPORT TEMPS IN
THE LOWER TO MIDDLE 70S. WILL HAVE EAST FLOW OFF LAKE THOUGH LAKE
SURFACE TEMPS NOW IN MID TO UPPER 60S SO HAVE CONFINED COOLING TO
CLOSER TO THE COAST. HAVE BUMPED MAX TEMPS UP A BIT MID WEEK.
&&
.AVIATION...FOR 06Z TAF ISSUANCE
ISSUED AT 1153 PM CDT SUN AUG 24 2014
AN AREA OF SHOWERS AND THUNDERSTORMS WILL MOVE ACROSS
THE AREA OVERNIGHT. THE ACTIVITY WILL PROBABLY ARRIVE IN
RHINELANDER AND WAUSAU BETWEEN 07 AND 09Z AND AT APPLETON...
OSHKOSH AND GREEN BAY BETWEEN 11Z AND 13Z IF IT HOLDS TOGETHER.
MVFR CEILINGS ARE A EXPECTED IN MOST PLACES WITH LOCAL IFR IN THE
NORTH.
&&
.GRB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM.....MPC
LONG TERM......TE
AVIATION.......RDM
AREA FORECAST DISCUSSION
NWS CHEYENNE WY
1023 PM MDT SUN AUG 24 2014
.SHORT TERM...(THIS EVENING THROUGH TUESDAY NIGHT)
ISSUED AT 345 PM MDT SUN AUG 24 2014
QUIET DAY TODAY WITH FAIR WEATHER CU DEVELOPING ACROSS THE AREA.
DEEP MIXING AND GUSTY WESTERLY WINDS HAVE RESULTED IN QUITE A BIT
OF DRIER AIR ALOFT MIXING DOWN TO THE SURFACE THIS
AFTERNOON...WITH NO DEEP CONVECTION OBSERVED. THE UPPER LEVEL LOW
WHICH BROUGHT RAIN AND TSTORMS TO THE AREA THE LAST FEW DAYS HAS
MOVED INTO NORTH DAKOTA AND WILL EVENTUALLY PUSH INTO
CANADA...WHILE THE NEXT WEATHER CONCERN FOR THIS WEEK IS CURRENTLY
DIGGING SOUTH ACROSS THE PACIFIC NORTHWEST. THIS IS THE NEXT UPPER
LEVEL TROUGH TO LIKELY IMPACT THE FORECAST AREA AND WILL EVENTUALLY
BECOME AN UPPER LEVEL LOW NEAR THE CENTRAL ROCKY MOUNTAINS BY THE
MIDDLE OF THE WEEK. BEFORE THEN...THIS SYSTEM WILL PRIMARILY ALLOW
THE JET STREAM TO SHIFT BACK TO THE NORTH AND INTENSIFY OVER THE
AREA TONIGHT. THERE IS A POTENTIAL FOR NOCTURNAL
CONVECTION...INCLUDING THUNDERSTORMS...TONIGHT ACROSS THE SOUTHERN
HALF OF THE FORECAST AREA...MAINLY SOUTH OF THE NORTH PLATTE RIVER
VALLEY.
THE UPPER LEVEL TROUGH WILL DIG SOUTH INTO THE GREAT BASIN ON
MONDAY. MODELS HAVE CONTINUED TO TREND SLOWER AND MORE AMPLIFIED
WITH THIS SYSTEM OVER THE LAST 3 DAYS AS THE TROUGH BECOMES A
CLOSED LOW SOMEWHERE BETWEEN NORTHERN NEVADA AND NORTHWEST
COLORADO. THE ECMWF AND GEM CONTINUE TO BE THE SLOWEST...WITH THE
GFS AND NAM NOT TOO FAR BEHIND NOW SINCE BOTH SOLUTIONS ARE
TRENDING TOWARDS THE ECMWF. WITH DECENT LOW TO MIDLEVEL
INSTABILITY...MOISTURE ADVECTION...AND CAPE OVER 1000
J/KG...EXPECT AFTERNOON SHOWERS AND TSTORMS TO DEVELOP ACROSS MOST
OF THE AREA. WITH THE LACK OF A DEFINED SHORTWAVE...DO NOT EXPECT
WIDESPREAD COVERAGE. IN FACT...MOST OF THE PANHANDLE MAY NOT SEE
ANY ACTIVITY AT ALL DUE TO THE CAP INVERSION AT 750 MB. KEPT
ISOLATED TSTORMS OVER THAT AREA AT BEST DURING THE AFTERNOON...BUT
MAY SEE AN INCREASE IN SHOWERS AND TSTORMS IN THE EVENING HOURS. A
FEW THUNDERSTORMS MAY BECOME STRONG OVER SOUTHEAST WYOMING. HIGH
TEMPERATURES WILL STRUGGLE TO REACH THE MID TO UPPER 70S ACROSS
MOST OF THE AREA DUE TO INCREASING SOUTHEAST WINDS.
SLOW MOVING CLOSED LOW WILL BARELY MAKE IT INTO WESTERN UTAH BY
TUESDAY...WITH ANOTHER DAY OF THUNDERSTORMS EXPECTED. TUESDAY
LOOKS TO BE A RATHER WET DAY AND ON THE COOL SIDE. ALTHOUGH THE
MAIN LOW WILL BE WELL TO THE WEST...MODELS INDICATE A POTENT
SHORTWAVE DISTURBANCE MOVING NORTHWARD OVER THE AREA. THE POSITION
AND TIMING OF THIS DISTURBANCE WILL INDICATE WHICH AREAS RECEIVE
LOCALLY HEAVY RAINFALL AND THE POTENTIAL FOR SEVERE TSTORMS.
INCREASED POP BETWEEN 40 TO 70 PERCENT ACROSS SOUTHEAST WYOMING ON
TUESDAY/TUESDAY EVENING. WESTERN NEBRASKA WILL STILL BE STRUGGLING
WITH A STRONG CAP INVERSION...SO KEPT POP BELOW 25 PERCENT FROM
SIDNEY TO CHADRON.
.LONG TERM...(WEDNESDAY THROUGH SATURDAY NIGHT)
12Z MODELS HAVE COME INTO SOME AGREEMENT WITH THE UPPER LEVEL LOW
THAT IS EXPECTED TO TRACK ACROSS THE ROCKIES ON WEDNESDAY AND
THURSDAY. AS IT STANDS...MODELS CONTINUE TO FAVOR THE SLOWER
EAST-SOUTHEAST PROGRESSION OF THE UPPER LOW...TRACKING IT OVER THE
ROCKIES THROUGH THURSDAY AND INTO THE CENTRAL PLAINS FRIDAY. THUS
WILL CONTINUE TO RELY MORE ON THIS SLOWER SOLUTION FOR THE EXTENDED
FORECAST. TEMPS WILL REMAIN BELOW AVERAGE WEDNESDAY AND THURSDAY
WITH AT LEAST A CHANCE FOR SCATTERED SHOWERS AND T-STORMS AS THE
UPPER LOW MOVES ACROSS WY/CO ON WEDNESDAY. WILL SEE A STEADY
DECREASE IN COVERAGE FROM WEST TO EAST THURSDAY. PWATS ARE PROGGED
TO BE 0.75 TO 1" OR MORE...AND WITH FAIRLY LIGHT STEERING FLOW OF 10
TO 15 KTS IN PLACE...THIS ACTIVITY COULD BE SLOW MOVING AND PRODUCE
HIGH RAIN RATES. THEREFORE FLOODING WILL BE THE MAIN CONCERN WITH
THIS SYSTEM. MODELS SHOW H7 TEMPS DROPPING TO 3C OVER THE MOUNTAINS
ON WEDNESDAY AS THE LOW CENTER MOVES OVERHEAD...SO ITS VERY POSSIBLE
THE HIGH ELEVATIONS ABOVE 10KFT WILL SEE SNOW MIXED IN WITH RAIN.
THIS SYSTEM WILL SLOWLY DEPART THE REGION THROUGH THE WEEKEND WITH A
WEAK RIDGE BUILDING IN FROM THE WEST FOR FRIDAY AND SATURDAY. A MUCH
DRIER AIRMASS WILL MOVE IN WITH THE RIDGE SO CHANCES FOR AFTN
SHOWERS AND STORMS WILL BE LOW THROUGH SATURDAY NIGHT. BREEZY
CONDITIONS ARE LIKELY ON SATURDAY AS THE LEESIDE SFC PRESSURE TROUGH
DEEPENS IN ADVANCE OF THE NEXT SYSTEM DIGGING INTO THE PAC NW FRI
NIGHT INTO SATURDAY. TEMPS WILL WARM BACK TO MORE NORMAL READINGS
FOR THIS TIME OF YEAR BY SATURDAY AS WELL.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY EVENING)
ISSUED AT 1020 PM MDT SUN AUG 24 2014
CONVECTION ON THE INCREASE ACROSS NORTHWESTERN COLORADO LATE THIS
EVENING. SOME LIGHTNING STRIKES VCNTY OF SARATOGA WYOMING. EXPECT
THESE STORMS TO EVENTUALLY MAKE IT INTO KLAR AND KCYS TOWARDS THE
07-08Z TIME FRAME. HRRR SHOWS THIS AREA OF SHOWERS AND
THUNDERSTORMS EVENTUALLY MAKING IT INTO THE PANHANDLE TOWARDS 12Z
BEFORE DISSIPATING. MORE WIDESPREAD SHOWERS AND THUNDERSTORMS
EXPECTED FOR MONDAY AFTERNOON AND EVENING.
&&
.FIRE WEATHER...
ISSUED AT 245 PM MDT SUN AUG 24 2014
NO FIRE WEATHER CONCERNS THIS WEEK DUE TO THE UNSETTLED WEATHER
PATTERN OVER THE AREA. AFTER A RATHER DRY DAY ON SUNDAY...MOISTURE
WILL QUICKLY RETURN TO THE AREA TONIGHT. MINIMUM RELATIVE
HUMIDITIES WILL TREND HIGHER...BETWEEN 30 TO 50 PERCENT ALONG
WITH EXCELLENT RECOVERIES OVERNIGHT. TEMPERATURES WILL BE COOLER
THAN NORMAL ACROSS MOST LOCATIONS THROUGH AT LEAST THURSDAY.
&&
.CYS WATCHES/WARNINGS/ADVISORIES...
WY...NONE.
NE...NONE.
&&
$$
SHORT TERM...TJT
LONG TERM...RJM
AVIATION...CLAYCOMB
FIRE WEATHER...TJT
AREA FORECAST DISCUSSION
NWS GRAND JUNCTION CO
1120 PM MDT TUE AUG 26 2014
.UPDATE...
ISSUED AT 938 PM MDT TUE AUG 26 2014
SWRN UTAH CONVECTION MOVES INTO SERN UTAH LATER THIS EVENING...BUT
WILL BE ENCOUNTERING A MORE STABLE REGIME. SURFACE TEMPS HAVE
COOLED SIGNIFICANTLY WITH READINGS IN THE UPPER 50S TO MID 60S.
SPC MESOANALYSIS ALSO SHOW OUR AIR MASS HAVE LESS INSTABILITY PER
MLCAPE VALUES. STRONG STORMS OVER SWRN UTAH WILL HAVE WEAKENED
SIGNIFICANTLY ONCE THIS ACTIVITY REACHES SERN UTAH. THUS THE
FLASH FLOOD WATCH WAS CANCELLED EARLIER THIS EVENING.
SHOWERS WITH EMBEDDED STORMS HAVE NOT ENDED AS A VORTICITY LOBE
ROTATES AROUND THE ANOMALOUS CLOSED LOW ALONG THE NEVADA/UTAH
BORDER. THE BAND OF MOISTURE OVER THE FOUR CORNERS GETS LIFTED
NORTHWARD AND WRAPS AROUND THE UPPER LOW...EXPANDING IN THE
PROCESS. THIS WILL RESULT IN WIDESPREAD SHOWERS ACROSS NE UTAH AND
THE NRN 2/3RDS WRN COLORADO. POTENTIAL EXISTS FOR SIGNIFICANT PCPN
IN THE UPSLOPE REGION OF THE UINTA MOUNTAINS...THE AREA NORTHWEST
OF VERNAL NEEDS TO MONITORED FOR ANY FLOOD POTENTIAL GIVEN NEAR
SATURATED GROUND. AREAL FLOOD ADVISORY ALREADY ISSUED FOR ERN
DAGGETT COUNTY IN THE JARVIE RANCH AS GRAVEL/DIRT ROADS HAVE BEEN
REPORTEDLY WASHED OUT.
UPPER LOW WILL BE ABOVE THE WESTERN SLOPE WEDNESDAY AFTERNOON. MAY
NEED TO CONSIDER THIS A SPRING COLD CORE SYSTEM WITH HIGHER
PRECIPITABLE WATER CONTENT. THE RAIN COOLED AIR MASS WILL HAVE
STABILIZE THE AIR MASS...EXPECT AFTERNOON DESTABILIZATION FROM MID
LEVEL COLD ADVECTION. WITH LOWER FREEZING LEVELS...SOME THUNDERSTORMS
WILL CONTAIN HAIL. ISOLATED LARGE HAIL IS POSSIBLE (ALTHOUGH THE
WIND SHEAR PROFILE IS NOT FAVORABLE)...BUT THE MORE LIKELY
SCENARIO IS PLENTY OF SMALL HAIL WITH SIGNIFICANT ACCUMULATION.
THE COOL WET AUGUST FOR THE NORTHERN AND CENTRAL AREAS OF THE
FORECAST AREA CONTINUES FOR ANOTHER DAY.
UPDATE ISSUED AT 625 PM MDT TUE AUG 26 2014
ANOMALOUS CLOSED LOW WILL TRACK TOWARD WRN COLORADO TONIGHT AND
WILL BE OVERHEAD ON WEDNESDAY AFTERNOON. MOISTURE SURGING
NORTHEAST FROM SRN UTAH AND ARIZONA WILL EVENTUALLY WRAP AROUND
THE MID LEVEL CIRCULATION WITH PRECIPITATION MORE FOCUSED ACROSS
THE NORTH BY WEDNESDAY. APPEARS THAT MUCH OF THE AREA WILL RECEIVE
SHOWERS WITH EMBEDDED STORMS ON WEDNESDAY. WILL TAKE ANOTHER LOOK
AT THE FORECAST PACKAGE WHEN THE 00Z HRRR ARRIVES WITH POSSIBLE
FORECAST UPDATES FOR WEDNESDAY.
&&
.SHORT TERM...(TONIGHT THROUGH WEDNESDAY NIGHT)
ISSUED AT 234 PM MDT TUE AUG 26 2014
CONVECTION STARTING TO GET GOING THIS AFTERNOON THANKS TO THE
CLOSED LOW OVER UTAH...AVAILABLE MOISTURE...UPPER LEVEL TROUGH
ROTATING AROUND LOW AND UPPER LEVEL DYNAMIC SUPPORT. MODEL DIFFERENCES
CONTINUE WITH SOME MODELS BEING MORE AGGRESSIVE THAN OTHERS WITH
HRRR STILL DOING PRETTY WELL PICKING UP ON MOST CONVECTION ACROSS
NM...UT...AZ...AND CO. WHILE SOME SHOWERS AND STORMS ARE MOVING
ACROSS THE CWA...THE HRRR SHOWS THE STRONGER CONVECTION ENTERING
SERN UT THIS EVENING AND THIS LOOKS TO BE PANNING OUT AS A LINE OF
SHOWERS AND STORMS HAS FORMED OVER CENTRAL AND S CENTRAL UTAH AND
IS TRACKING EASTWARD. HIGH SPECIFIC HUMIDITIES LENDING THEMSELVES
TO SOME HEAVY RAINERS SO THE FLASH FLOOD WATCHES WILL REMAIN IN
EFFECT.
RAIN WITH SOME EMBEDDED STORMS WILL CONTINUE OVERNIGHT AS THE
UPPER LEVEL LOW APPROACHES THE FORECAST AREA. THE STORMS AND
SHOWERS OVER THE SAN JUANS WILL SHIFT NORTHWARD AS THE NIGHT
PROGRESSES AND BEST UPPER LEVEL SUPPORT ALSO SHIFTS TO THE
NORTH...STILL ROTATING AROUND THE LOW PRESSURE. SNOW LEVELS ARE
EXPECTED TO DROP NEAR 13K FEET OR SO OVERNIGHT WITH A LIGHT
DUSTING OF SNOW POSSIBLE FOR ELEVATIONS ABOVE THAT. FOR
TOMORROW...MOST PRECIP WILL BE UP NORTH AS THE LOW PRESSURE STARTS
TO FILL AND MOVE OVER UT AND CO. HOWEVER...AS THE LOW MOVES OVER
THE CWA DURING THE DAY UPPER LEVEL DYNAMICS WILL AGAIN PLAY A
FACTOR WITH MORE PRECIP ON TAP FOR MAINLY THE SAN JUANS NORTHWARD.
TEMPERATURES WILL STAY BELOW NORMAL THROUGH THE PERIOD DUE TO
PRECIP AND CLOUDINESS.
.LONG TERM...(THURSDAY THROUGH TUESDAY)
ISSUED AT 234 PM MDT TUE AUG 26 2014
THE UPPER TROUGH DROPS ONTO THE EASTERN PLAINS ON THURSDAY WITH
THE WESTERN MOST ASSOCIATED SHOWERS CLOSE TO THE CONTINENTAL
DIVIDE FAVORING NW-FACING SLOPES. THESE SHOWERS ARE EXPECTED TO
END BY THURSDAY EVENING.
A FLAT RIDGE TRIES TO BUILD IN FROM THE SOUTHWEST ON FRIDAY.
RESIDUAL MOISTURE WILL ALLOW LATE-DAY STORMS TO FIRE MAINLY OVER
THE HIGHER COLORADO TERRAIN. THE RIDGE GETS FLATTENED ON SATURDAY
AS THE NEXT GULF OF ALASKA TROUGH DIGS INTO THE PACIFIC NW.
SATURDAY STILL LOOKS LIKE THE WARMEST DAY OF THE WEEK PERHAPS
HITTING 90 DEGREES ONCE AGAIN IN GRAND JUNCTION AND NEAR 100 IN
THE SE UTAH LOWLANDS.
THE PACIFIC TROUGH WILL PROGRESS THROUGH THE NORTHERN ROCKIES
SUNDAY INTO MONDAY. ITS 100KT JET STREAK SWEEPS THROUGH SOUTHERN
WYOMING. THIS MAY PRODUCE SCATTERED STORMS ACROSS THE NORTHERN
MTNS SUNDAY WITH A FEW STORMS PERSISTING INTO MONDAY. THESE STORMS
WILL BE MOVING TO THE EAST AT 45 MPH SO STRONG WINDS ARE A THREAT.
ELSEWHERE SUNDAY AND MONDAY WILL HAVE BREEZY AFTERNOON WINDS WITH
A SLIGHT COOL DOWN RECOVERING SOMEWHAT ON TUESDAY AS THE TROUGH
WORKS ACROSS THE NORTHERN PLAINS.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z WEDNESDAY NIGHT)
ISSUED AT 1119 PM MDT TUE AUG 26 2014
NUMEROUS SHOWERS EXPECTED WITH EMBEDDED THUNDERSTORMS THROUGH THE
FORECAST PERIOD. THE STRONGEST STORMS WILL PRODUCE 4SM
+SHRA/+TSRAGS WITH CIGS LOWERING TO BELOW AIRFIELD MINIMUMS FOR
THE MOUNTAIN TAF SITES. CONVECTIVE TURBULENCE SHOULD BE EXPECTED
WITH OCCASIONAL MOUNTAIN TOP OBSCURATIONS. SOME IMPROVEMENT IS
EXPECTED ACROSS THE FAR SOUTH ON LATE WEDNESDAY AFTERNOON AND
EVENING WITH A DECREASING CHANCE FOR -SHRA/-TSRA.
&&
.GJT WATCHES/WARNINGS/ADVISORIES...
CO...NONE.
UT...NONE.
&&
$$
UPDATE...PF
SHORT TERM...TGR
LONG TERM...JOE
AVIATION...TGJT
AREA FORECAST DISCUSSION
NWS TAMPA BAY RUSKIN FL
340 AM EDT WED AUG 27 2014
.SYNOPSIS...
07Z WATER VAPOR AND H4 RAP ANALYSIS SHOW THE MAIN NORTHERN STREAM
FLOW ALIGNED WELL TO THE NORTH NEAR THE CONUS/CANADIAN BORDER. SOUTH
OF THIS MAIN FLOW...TWO FEATURES DOMINATE THE CONUS WEATHER
INCLUDING A POTENT TROUGH/UPPER LOW PROGRESSING EASTWARD OVER THE
INTERMOUNTAIN WEST...AND A LONGWAVE RIDGE COVERING MUCH OF THE DEEP
SOUTH TO THE EASTERN SEABOARD. THIS RIDGE HAS EXPANDED SOUTHWARD
OVER THE PAST 24 HOURS AND IS NOW FIRMLY IN CONTROL OVER THE FL
PENINSULA. HURRICANE CRISTOBAL STICKS OUT ON THE UPPER AIR CHARTS AS
WELL OFF THE SE CONUS COASTLINE EARLY THIS MORNING...HOWEVER
CRISTOBAL IS NOW PULLING AWAY FROM OUR REGION AND WILL ONLY INCREASE
ITS DISTANCE THROUGH THE DAY.
AS WAS TALKED ABOUT MONDAY NIGHT...A VERY ANOMALOUS AIRMASS HAS
ARRIVED OVERHEAD WITHIN DEEP LAYER NORTH/NE FLOW. THE 27/00Z KTBW
SOUNDING PROFILE SHOWS ALL THE ANTICIPATED FEATURES. THE COLUMN PW
IS NOT RECORD SETTING...BUT IS EXTREMELY DRY FOR AUGUST...AND OUR
MID-LEVEL TEMPS ARE NEAR OR AT ALL TIME HIGHS FOR AUGUST. THE
MEASURED PW VALUE OFF THE KTBW SOUNDING WAS AROUND 1.25"...WHICH IS
MORE THAN 2 STANDARD DEVIATIONS BELOW CLIMATOLOGY FOR LATE AUGUST.
THE 500MB TEMP WAS BETWEEN -1C AND -2C WHICH IS GREATER THAN THE 99%
PERCENTILE OF VALUES FOR AUGUST. THIS VERY DRY COLUMN AND EXTREMELY
POOR LAPSE RATES BELOW 500MB CONTRIBUTED HIGHLY THE LACK OF DEEP
CONVECTION ON TUESDAY.
THE ONLY REAL MOISTURE IN THE COLUMN IS IN THE LOWER LEVELS
ASSOCIATED WITH ATLANTIC MOISTURE ARRIVING ON STEADY NORTHEAST
WINDS. SEEING A FEW ISOLATED AND VERY SHALLOW SPEED CONVERGENCE
SPRINKLES MAKING THERE WAY ACROSS THE PENINSULA FROM THE EAST COAST
EARLY THIS MORNING...HOWEVER DO NOT EXPECT ANY MEASURABLE PRECIP
FROM ANY OF THESE. IN FACT...AS CRISTOBAL CONTINUES TO MOVE AWAY AND
HIGH PRESSURE DIGS SOUTHWARD INTO THE SOUTHEAST CONUS...THE GRADIENT
WILL BE WEAKENING WITH TIME TODAY...MAKING CONDITIONS LESS EFFICIENT
FOR THE SPEED CONVERGENCE SHOWERS PRODUCTION.
&&
.SHORT TERM (TODAY THROUGH THURSDAY)...
TODAY...
WE ARE ONLY GOING TO SEE SLIGHT COOLING ALOFT TODAY...AND ONLY
SLIGHT MOISTENING THROUGH THE COLUMN. THEREFORE...DEEP CONVECTIVE IS
STILL GOING TO ONCE AGAIN HAVE A VERY DIFFICULT TIME . IF ANY
ISOLATED STORMS WILL BE ABLE TO GROW LATE IN THE AFTERNOON OR
EVENING...IT SHOULD BE WELL SOUTH OF THE I-4 CORRIDOR WHERE THE
"GREATEST" MODERATION OF THE AIRMASS WILL HAVE OCCURRED BY 21-00Z.
GREATEST IS IN QUOTES BECAUSE EVEN OVER OUR SOUTHERN ZONES THE
MODERATION IS MINOR. YESTERDAY WE WERE DISCUSSING HOW THE NAM WAS
AGGRESSIVE IN PIVOTING A SURFACE TROUGH NORTHWARD OUT OF THE
SOUTHEAST GULF OF MEXICO AND RETURNING DECENT MOISTURE TO OUR
SOUTHERN ZONES BY LATE TODAY. WELL...THE NAM IS STILL THE MOST
AGGRESSIVE BUT HAS BACKED OFF CONSIDERABLY FROM ITS SOLUTION FROM 24
HOURS AGO. IT APPEARS AS THOUGH THE GFS/ECMWF SOLUTIONS FROM
YESTERDAY WILL BE CLOSER TO REALITY WITH THE TRUE TRANSITION DAY
TOWARD A COLUMN MORE FAVORABLE TO DEEP CONVECTION BEING THURSDAY.
USING THE ABOVE PHILOSOPHY...THE SENSIBLE WEATHER FORECAST FOR TODAY
WILL FEATURE MAINLY DRY CONDITIONS WITH TEMPERATURES IN THE LOWER TO
MIDDLE 90S. THERE WILL BE A SLIGHT CHANCE OF A VERY LATE DAY SHOWER
OR ISOLATED STORM TO THE SOUTH OF I-4...BUT COVERAGE SHOULD BE VERY
LIMITED (IF THEY OCCUR). MOST OF THE HIRES CONVECTION ALLOWING
GUIDANCE MEMBERS ONLY SHOW ISOLATED AND BRIEF DURATION CELLS...AND
HAVE FOUND THAT MANY OF THESE MODELS AND THERE MICROPHYSICS SCHEMES
ARE OFTEN BIASED TOWARD THE AGGRESSIVE SIDE WHEN IT COMES TO DEEP
CONVECTION. THE GRADIENT WILL BE WEAKENING TODAY...SO THE BREEZY
CONDITIONS FROM THE EAST SEEN THE PAST TWO DAYS WILL NOT BE AS
PRONOUNCED. GRADIENT SHOULD RELAX ENOUGH BY THE SECOND HALF OF THE
AFTERNOON TO SUPPORT SEA-BREEZE DEVELOPMENT...SO EXPECT WINDS TO
EVENTUALLY SHIFT ONSHORE NEAR THE BEACHES.
TONIGHT...
ENSEMBLE NWP SUITE SHOW THE WEST TO EAST ELONGATED SURFACE TROUGH
WILL BEGIN TO PIVOT NORTHWARD INTO THE SOUTHERN HALF OF THE
PENINSULA DURING THE OVERNIGHT. THIS TROUGH AXIS REPRESENTS THE
LEADING EDGE OF THE DEEPER MOISTURE RETURN WHICH LOOKS TO BE
REACHING OUR FAR SOUTHERN ZONES DOWN TOWARD FORT MYERS EARLY
THURSDAY MORNING. THIS TROUGH IS DEFINED ENOUGH THAT THERE IS A
DECENT SWATH OF SURFACE FOCUS/CONVERGENCE PIVOTING NORTHWARD WITH
IT. GENERALLY SPEAKING...DO NOT ANTICIPATE MUCH SHOWER ACTIVITY
DURING THE OVERNIGHT OVER OUR SOUTHERN LAND ZONES DUE TO THE MINIMUM
OF INSTABILITY AND RESIDUAL DRY AIR ALOFT. HOWEVER...ANTICIPATE
BETTER CHANCES FOR SHOWERS DURING THE SECOND HALF OF THE NIGHT OVER
THE SOUTHERN COASTAL WATERS WHERE LOW LEVEL INSTABILITY IS
MAXIMIZED. STILL WILL BE DEALING WITH THE DRIER AIR ALOFT TO LIMIT
THE GROWTH POTENTIAL...BUT WILL INCLUDE CHANCE POPS FOR SHOWERS/ISO
STORMS OVER THE COASTAL WATERS AFTER 06Z TO THE SOUTH OF TAMPA BAY.
THURSDAY...
THURSDAY BEGINS THE TRUE TRANSITION BACK TO A MORE TYPICAL LATE
SUMMER PATTERN FOR THE END OF THE WEEK. LOOKING AT PRETTY GOOD
AGREEMENT BETWEEN THE NWP MEMBERS REGARDING THE TIMING OF A RATHER
SHARP MOISTURE GRADIENT IN THE LOWER/MIDDLE LEVELS MOVING NORTHWARD
THROUGH THE DAY. APPEARS THIS GRADIENT WILL REACH NORTHWARD TO
AROUND THE I-4 CORRIDOR BY EARLY EVENING. THEREFORE THE BEST
ENVIRONMENT FOR DIURNAL STORMS GROWTH...AIDED BY THE FOCUS OF THE
SURFACE TROUGH WILL BE SOUTH OF TAMPA BAY. THIS BETTER ENVIRONMENT
MAY REACH AS FAR NORTH AS THE I-4 CORRIDOR BY THE EVENING HOURS
ALLOWING FOR SOME STORM DEVELOPMENT...BUT APPEARS ANY FURTHER NORTH
INTO THE NATURE COAST...AND THE MOISTURE WILL ARRIVE A LITTLE TOO
LATE FOR ANY SIGNIFICANT CONVECTIVE DEVELOPMENT. ANY SPEEDING UP OF
THIS MOISTURE RETURN AND BETTER STORM CHANCES WILL NEED TO BE
ADJUSTED NORTHWARD THURSDAY AFTERNOON/EVENING...BUT THE OUTLINED
SCENARIO ABOVE IS HOW IT CURRENTLY LOOKS WITH THE AVAILABLE
GUIDANCE...AND WILL BE THE FORECAST WE GO WITH EARLY THIS MORNING.
RAIN CHANCES THE SECOND HALF OF THURSDAY WILL RANGE FROM 10% UP
TOWARD CITRUS/LEVY COUNTIES...TO 30% ALONG THE I-4 CORRIDOR...AND
THEN RANGE UP TO LIKELY 60% THUNDER CHANCES DOWN TOWARD
CHARLOTTE/LEE COUNTIES. THEREAFTER IT APPEARS AS THROUGH EVERYONE
WILL BE GETTING INTO THE HIGHER RAIN CHANCES BY FRIDAY AFTERNOON AND
EVENING.
ENJOY THE DRIER CONDITIONS AND HAVE A GREAT WEDNESDAY!
&&
.LONG TERM (FRIDAY THROUGH NEXT TUESDAY)...
AN UPPER RIDGE MEANDERS AROUND THE REGION...WHILE REMAINING
GENERALLY CENTERED ABOVE THE SOUTHEAST U.S. COAST...THROUGH THE
PERIOD AS IT DOMINATES THE LOCAL AREA. HOWEVER A WEAK UPPER
TROUGH/LOW APPROACHES FROM THE EAST...REACHING THE BAHAMAS AS A
TROUGH (GFS) OR CUBA AS A LOW (ECMWF) TUE. AT THE SURFACE A BROAD
RIDGE STRETCHES ACROSS FL FROM THE ATLANTIC TO THE CENTRAL GULF.
INITIALLY THE RIDGE AXIS...
SOME WHAT ILL DEFINED...IS ACROSS CENTRAL FL BUT LIFTS UP TO ALONG
THE GA/FL LINE FOR THE WEEKEND THEN DROPS BACK INTO NORTHERN FL FOR
THE START OF NEXT WEEK. BOTH THE GFS AND ECMWF ARE SIMILAR WITH THE
SURFACE FEATURES EXCEPT FOR THE GFS TRACKING AN INVERTED TROUGH...ON
THE SOUTH SIDE OF THE RIDGE...INTO THE BAHAMAS TUE.
THE FORECAST PHILOSOPHY FROM 24 HOURS AGO CONTINUES WITH LITTLE
CHANGE. THE UPPER RIDGE WILL HELP KEEP TEMPERATURES ON THE WARM SIDE
OF NORMAL...LOWS BY A DEGREE OR TWO AND HIGHS AROUND A COUPLE OF
DEGREES. LOW LEVEL SOUTHEAST AND SOUTHERLY FLOW WILL RESULT IN
ENOUGH MOISTURE...MODEL PWAT VALUES RUN IN THE 1.8 TO 2 INCH
RANGE...FOR ISOLATED TO SCATTERED SHOWERS AND THUNDERSTORMS. SOME
DRIER AIR MAY WORK IN LATE MON AND TUE...IN THE GFS SOLUTION...BUT
STILL ENOUGH FOR SCATTERED COVERAGE. THE GRADIENT STAYS RELAXED WITH
SEA BREEZES SHIFTING THE FLOW TO ONSHORE IN THE AFTERNOONS...
FOCUSING THE GREATEST COVERAGE INLAND BUT NEAR THE COAST.
&&
.AVIATION...
VFR CONDITIONS ACROSS THE REGION EARLY THIS MORNING. PATCHES OF
CLOUDS HAVE BEEN MOVING NORTHEAST TO SOUTHWEST ACROSS THE CENTRAL
PENINSULA WITH PERIOD OF BROKEN CIGS FOR KSRQ/KPIE/KTPA/KLAL...BUT
BASES ARE GENERALLY ABOVE 5KFT. GENERAL VFR CONDITIONS WILL CONTINUE
THROUGH THE DAYLIGHT HOURS. JUST A SLIGHT CHANCE A LATE DAY SHOWER
FOR KFMY/KRSW. ALLOWED A SEA-BREEZE WINDS SHIFT LATE IN THE
AFTERNOON FOR KTPA/KPIE/KSRQ. LESS CONFIDENT IN THE BREEZE REACHING
KFMY/KRSW AND KEPT WINDS FROM THE EAST INTO THE EVENING HOURS.
&&
.MARINE...
THE GRADIENT REMAINS TIGHT ENOUGH EARLY THIS MORNING TO SUPPORT
AREAS OF CAUTIONARY LEVEL WINDS OVER THE EASTERN GULF OF
MEXICO...HOWEVER AS HURRICANE CRISTOBAL CONTINUES TO PULL FURTHER
AWAY FROM THE REGION AND HIGH PRESSURE DIGS SOUTHWARD TOWARD THE
AREA...THIS GRADIENT WILL BE RELAXING AND SHOULD SEE AN EARLY END TO
THE CAUTIONARY CONDITIONS THIS MORNING. WINDS WILL SHIFT TO THE
SOUTHEAST FOR THE LATER PORTION OF THE WEEK AS A WEAK SURFACE TROUGH
PIVOTS NORTHWARD ACROSS THE CENTRAL AND EASTERN GULF OF MEXICO.
ALTHOUGH WINDS AND SEAS ARE EXPECTED TO REMAIN BELOW HEADLINE
CRITERIA...THIS TROUGH WILL BRING GREATER COVERAGE OF SHOWERS AND
STORMS TO THE COASTAL WATERS.
&&
.FIRE WEATHER...
ANOTHER GENERALLY DRY DAY WITH LITTLE IN THE WAY OF THUNDERSTORM
ACTIVITY. RELATIVE HUMIDITY VALUES WILL BE LOW FOR LATE SUMMER...BUT
ARE NOT EXPECTED TO DROP BELOW CRITICAL LEVELS. LOW LEVEL MOISTURE
ALONG WITH THUNDERSTORM CHANCES WILL THEN QUICKLY INCREASE BACK TO
NORMAL LEVELS FOR LATE AUGUST BY THE END OF THE WEEK. NO SIGNIFICANT
FOG IS EXPECTED THE NEXT SEVERAL DAYS.
&&
.PRELIMINARY POINT TEMPS/POPS...
TPA 94 77 93 78 / 10 10 20 20
FMY 95 76 93 76 / 20 20 60 30
GIF 93 74 95 75 / 10 10 20 20
SRQ 92 75 92 77 / 10 10 40 30
BKV 94 70 95 73 / 10 10 20 20
SPG 93 80 93 80 / 10 10 30 30
&&
.TBW WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
GULF WATERS...NONE.
&&
$$
SYNOPSIS/SHORT TERM/AVIATION/MARINE/FIRE WX...MROCZKA
LONG TERM...RUDE
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
1238 AM CDT WED AUG 27 2014
.DISCUSSION...
255 PM CDT
AS HAS BEEN THE NORM IN THE PAST WEEK TO TEN DAYS...THE PRIMARY
FORECAST CHALLENGES ARE TRYING TO DETECT WHEN BETTER THUNDERSTORM
CHANCES MAY BE AND WHAT INFLUENCE THOSE HAVE...IF ANY...ON
TEMPERATURES.
.TONIGHT...
THE INITIAL SYNOPTIC COLD FRONT HAS APPEARED TO CLEAR THE
FORECAST AREA. THIS SURGE WAS CONVECTIVELY ENHANCED AND LINGERING
HIGH DEW POINT AIR...E.G. UPPER 60S TO LOWER 70S...REMAINS ACROSS
THE SOUTH. THERE ALSO ARE ONE OR TWO WESTWARD-PROPAGATING OUTFLOW
BOUNDARIES THAT ARE LIKELY TO LAST INTO LATE THIS AFTERNOON.
CUMULUS HAS FORMED NEAR PONTIAC AND GIBSON CITY...AND BACK TOWARD
PRINCETON TO MENDOTA...WITH THESE FEATURES. WOULD NOT BE TOTALLY
SURPRISED TO SEE ISOLATED STORMS POP ON THESE AS MIXED LAYER
INHIBITION APPEARS SHALLOW WITH RECOVERING TEMPERATURES INTO THE
MID 80S AND EVEN 88 AT PONTIAC. A COUPLE SUBTLE SHORT WAVES ARE
NOTED ON WATER VAPOR...WITH ONE A LITTLE BETTER DEFINED ON
VISIBLE SATELLITE NEARING THE MISSISSIPPI RIVER FROM IA ASSOCIATED
WITH A 35 KT 500MB SPEED MAXIMUM. THIS LOOKS TO PASS OVER NORTH
CENTRAL IL EARLY THIS EVE AND COULD SEE SOME SHOWER/STORM ACTIVITY
WITH THAT...ALTHOUGH CONFIDENCE IS LOW FOR SHORT TERM STORM
CHANCES...SO HAVE KEPT POPS FAIRLY LOW. CONFLUENT 700-850MB FLOW
CONTINUES OVERNIGHT WITH ANOTHER LITTLE RIPPLE IN THE FLOW
FORECAST TO MOVE OVER THE AREA. SO CONTINUE CHANCE FOR A STORM
THROUGH THE ENTIRE NIGHT...BUT NOT EXPECTING ANYTHING WIDESPREAD.
INCOMING CLOUDS FROM THE DISTURBED MID-LEVEL FLOW SHOULD KEEP THE FOG
THREAT MINIMAL...AND TEMP/DEW POINT SPREADS LOOK TO BE MODESTLY
HIGH GOING INTO TONIGHT IN MOST AREAS...OUTSIDE OF THE FAR SOUTH.
MTF
.WEDNESDAY THROUGH TUESDAY...
THE LONGWAVE PATTERN OVER THE CENTRAL CONUS HAS BECOME MORE ZONAL
WITH TROPICAL SYSTEM OVER SERN ATLANTIC...NERN PACIFIC WHILE A BROAD
HIGH SITS OVER THE SRN CONUS AND A CLOSED UPPER LOW SWINGS THROUGH
THE GREAT BASIN. THE SENSIBLE WEATHER OVER THE CWA WILL CONTINUE TO
BE UNSETTLED AS A STRONG SHORTWAVE QUICKLY MOVES ACROSS THE UPPER
MISSISSIPPI VALLEY AND GREAT LAKES WEDNESDAY. UPPER RIDGING SHOULD
BUILD ACROSS THE MIDWEST ON THURSDAY AS MORE SHORT WAVE ENERGY
OVERTOPS THE RIDGE AND TRACKS ACROSS THE UPPER MIDWEST AND THE LOWER
GREAT LAKES REGIONS. BY THURSDAY NIGHT AND FRIDAY...THE UPPER RIDGE
SHOULD BUILD TO THE EAST OF THE REGION AS THE UPPER LOW OVER THE
GREAT BASIN FINALLY OPENS UP AND LIFTS EAST ACROSS THE CENTRAL
PLAINS AS AN OPEN WAVE FRIDAY AND FRIDAY NIGHT. THIS WAVE WILL
CROSS THE UPPER MIDWEST INTO THE WESTERN GREAT LAKES BY SUNDAY. THE
LONGER RANGE GUIDANCE SUGGESTS THAT THIS WAVE WILL PHASE WITH
ANOTHER NORTHERN STREAM SHORTWAVE OVER THE UPPER GREAT LAKES BY
SUNDAY. THE PROGRESSIVE AND RELATIVELY LOW AMPLITUDE UPPER LEVEL
PATTERN OVER THE CONUS WILL LEAD TO A CONTINUES ACTIVE WEATHER
PATTERN FOR THE LOCAL AREA...WITH PERIODIC CHANCES FOR SHOWERS AND
THUNDERSTORMS THROUGH MUCH OF THE PERIOD. THE SOUTHERN PORTIONS OF
THE CWA WILL BE MORE FAVORABLE FOR ADDITIONAL PCPN WEDNESDAY AS SFC
HIGH PRESSURE SPREADS ACROSS THE GREAT LAKES REGION AND THE OLD
FRONTAL BOUNDARY LAYS OUT ALONG THE OHIO VALLEY INTO SRN ILLINOIS.
AS A SFC LOW DEEPENS OVER THE CENTRAL PLAINS ON THURSDAY...IT WILL
DRAG THE FRONT NORTH AGAIN AS A WARM FRONT...BRINGING GREATER
CHANCES FOR MORE WIDESPREAD PCPN TO THE AREA FOR THURSDAY AND
THURSDAY NIGHT. WHILE THE FRONT REMAINS TO THE SOUTH AND HIGH
PRESSURE SPREADS ACROSS THE GREAT LAKES REGION...TEMPERATURES WILL
DIP BACK INTO THE MIDDLE 70S ACROSS THE NORTHERN PORTIONS OF THE CWA
WHILE THE SOUTHERN LOCATIONS MAY REACH THE LOWER 80S. BY
FRIDAY...WHEN THE WARM FRONT LIFTS NORTH OF THE CWA...HOT AND HUMID
CONDITIONS WILL RETURN...WITH HIGHS IN THE MIDDLE 80S...DEWPOINTS IN
THE LOWER 70S AND MAX HEAT INDEX VALUES INTO THE LOWER 90S. THE
DEVELOPING SFC LOW IS EXPECTED TO SLOWLY LIFT ACROSS THE UPPER
MISSISSIPPI VALLEY ON SATURDAY...KEEPING THE LOCAL AREA UNDER WARM
SECTOR AIR AHEAD OF AN ASSOCIATED COLD FRONT. WHILE THE AREA
REMAINS IN THE WARM SECTOR THROUGH THE WEEKEND...THERE WILL CONTINUE
TO BE CHANCES FOR SCATTERED SHOWERS AND THUNDERSTORMS...BUT WITHOUT
A STRONG FOCUSING MECHANISM...WILL KEEP POPS IN THE CHANCE RANGE.
BY EARLY NEXT WEEK...THE LONG RANGE GUIDANCE IS SUGGESTING THAT THE
COLD FRONT SHOULD FINALLY PUSH THROUGH THE AREA...BUT THERE SHOULD
BE LITTLE IN THE WAY OF AIRMASS CHANGE WITH THE FROPA AS ANOTHER
DEEPENING TROUGH OVER THE NORTHERN PLAINS SHOULD QUICKLY BRING A
RETURN TO WARM...MOIST SOUTHERLY FLOW FOR EARLY NEXT WEEK...WHICH
WILL...IN TURN...KEEP CONTINUES CHANCES FOR PCPN ACROSS THE REGION.
KREIN
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 06Z...
* POSSIBLE MVFR CIGS EARLY THIS MORNING.
* EAST/NORTHEAST WINDS THRU THE PERIOD...POSSIBLY AROUND 10KT THIS
AFTERNOON. CMS
//DISCUSSION...UPDATED 06Z...
HIGH PRESSURE OVER THE NORTHERN PLAINS WILL MOVE EAST ACROSS THE
LAKES REGION LATER TODAY AND TONIGHT. THIS WILL MAINTAIN EAST/
NORTHEAST WINDS THROUGH THE PERIOD. SPEEDS COULD INCREASE TO 10KTS
OR SLIGHTLY HIGHER THIS AFTERNOON INTO EARLY THIS EVENING WITH A
POSSIBLE LAKE BREEZE.
CIGS AROUND 3KFT HAVE DEVELOPED ACROSS NORTHEAST IL BUT APPEAR TO
BE SHIFTING EAST AND FOR NOW WILL JUST CARRY SCT MENTION. APPEARS
A BKN/OVC MID DECK WILL SPREAD ACROSS MUCH OF THE REGION OVERNIGHT
AND CONTINUE INTO THIS AFTERNOON. SOME FOG IS POSSIBLE WHERE SKIES
REMAIN MOSTLY CLEAR AND GENERALLY SOUTH AND SOUTHEAST OF THE
TERMINALS. CONTINUED FOG MENTION AT GYY BUT CONFIDENCE TOO LOW
ELSEWHERE.
A FEW ECHOS SHOWING UP ON RADAR NEAR THE QUAD CITIES AND ITS
POSSIBLE FOR A LIGHT SHOWER OR SOME SPRINKLES OUT OF THE MID DECK
THRU MID MORNING. CMS
//ORD AND MDW CONFIDENCE...UPDATED 06Z...
* LOW FOR MVFR CIGS EARLY THIS MORNING.
* MEDIUM FOR WINDS THRU THE PERIOD. CMS
//OUTLOOK FOR ORD/MDW FOR 12Z THURSDAY-12Z TUESDAY...UPDATED 00Z...
* THURSDAY THROUGH MONDAY...CHANCE OF TSRA.
KJB
&&
.MARINE...
250 PM CDT
LOW PRESSURE CONTINUES TO TRACK OUT OF NORTHERN QUEBEC AS A TRAILING
COLD FRONT EXTENDS SOUTHWEST THROUGH NORTHERN INDIANA AND INTO
SOUTHERN ILLINOIS. THE FRONT SHOULD STALL OUT OVER THE OHIO VALLEY
OVERNIGHT TONIGHT AND HIGH PRESSURE BUILDS ACROSS UPPER MISSISSIPPI
VALLEY AND WESTERN GREAT LAKES. WINDS OVER THE LAKE HAVE BEEN
DISRUPTED BY THUNDERSTORM ACTIVITY TODAY...BUT SHOULD SETTLE INTO A
MORE NORTHERLY TO NORTHEASTERLY DIRECTION OVERNIGHT TONIGHT. THE
HIGH IS EXPECTED TO BUILD ACROSS THE UPPER GREAT LAKES WEDNESDAY
NIGHT WHILE LOW PRESSURE DEEPENS OVER THE CENTRAL PLAINS. WINDS
OVER THE NORTHERN PORTIONS OF THE LAKE SHOULD THEN BECOME SOMEWHAT
VARIABLE IN DIRECTION AS THE CENTER OF THE HIGH MOVES OVER THE FAR
NORTHERN PORTION OF THE LAKE...BUT THE SOUTHERN PORTIONS OF THE LAKE
SHOULD MAINTAIN A NORTHEASTERLY TO EASTERLY FETCH. THE PERSISTENT
NORTHEASTERLY TO EASTERLY FETCH SHOULD CAUSE WINDS TO PILE UP OVER
THE WESTERN SHORE OF THE LAKE...APPROACHING 3-4FT AS WINDS REACH
10-20KT. THE HIGH WILL CONTINUE TO BUILD TO THE EAST THURSDAY AND
FRIDAY AS LOW PRESSURE TRACKS NEWD ONTO THE UPPER MISSOURI VALLEY.
THIS WILL...IN TURN...LIFT THE OLD FRONTAL BOUNDARY THAT HAD GONE
STATIONARY OVER THE OHIO VALLEY TO LIFT NORTH AS A WARM FRONT TURING
WINDS THROUGH SOUTHEASTERLY TO SOUTHERLY BY FRIDAY.
AS HAS BEEN THE NORM IN THE PAST WEEK TO TEN DAYS...THE PRIMARY
FORECAST CHALLENGES ARE MUCH WHAT THEY HAVE BEEN...TRYING TO DETECT
WHEN BETTER THUNDERSTORM CHANCES MAY BE AND WHAT INFLUENCE THOSE
CONVECTIVE CHANCES HAVE ON TEMPERATURES.
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
1151 PM CDT Tue Aug 26 2014
.UPDATE...
ISSUED AT 845 PM CDT TUE AUG 26 2014
Band of strong/severe storms has been slowly trudging southward
along the frontal boundary roughly along the the I-72 corridor.
The models are generally handling this convection extremely
poorly, although the 21Z online HopWRF is doing a pretty decent
job, with the NamDNG5 also in the general vicinity. The HopWRF
shows a general push toward the I-70 corridor over the next couple
hours, and there is a lingering outflow that extends from near
Flora northwest toward Taylorville, so that could feed some
additional development. The front will not be moving too much
overnight, and the RAP and 18Z NAM show some redevelopment north
of it after 2-3am.
Have sent some updated grids/zones to significantly increase the
PoP`s this evening with this convection. Have not looked too
closely at the temperatures yet, so further updates may be needed
once that is evaluated.
&&
.SHORT TERM...(This evening through Wednesday)
ISSUED AT 316 PM CDT TUE AUG 26 2014
An outflow boundary is draped over the area this afternoon and this
could be the focus for more showers and thunderstorm development
this evening and into tonight. So will be keeping a chance pops in
the forecast for tonight, but mainly along and northeast of I-74. By
tomorrow, all models indicate a good chance of thunderstorms across
most of the area through tomorrow afternoon. Things will then shift
back to the west after that.
Temps and dew points are remaining high so will keep the heat
advisory and warning going through this evening. Temps will remain
warm through tomorrow, but with clouds and pcpn, advisory/warning
criteria for heat indices will not be met. Model guidance numbers
look to be too warm.
&&
.LONG TERM...(Wednesday night through Tuesday)
ISSUED AT 316 PM CDT TUE AUG 26 2014
Upper level ridging will be broken down, which will allow another
cold front to move into the area late in the week. Unfortunately
this means that the chance of showers and thunderstorms will
continue into the weekend. Most of the pcpn chances will remain to
the northwest or northern part of the CWA through Friday. Then when
the front drops into the area Friday afternoon, the chance of
thunderstorms will spread across the whole CWA for most of the
weekend. There could be a break in the pcpn over some of the area
Sunday night, but another frontal system will move into the region
for the beginning of next week...so chance pops continue.
Temps will cool through the period, but then warm back up during the
beginning of next week. Model guidance still looks to be too warm.
&&
.AVIATION...(For the 06Z TAFS through 06Z Wednesday night)
ISSUED AT 1150 PM CDT TUE AUG 26 2014
Predominantly VFR aviation weather conditions expected across the
central Illinois terminals through the 06Z TAF valid time. Still
looks like a brief period of MVFR fog is possible later tonight,
although the convective debris cloud in the area make this a
little less certain than it seemed earlier tonight. Precipitation
for the period is likely to be quite tricky. Feel the bulk of the
night should be dry, and much of Wednesday may be as well.
However, with a weak cold front slipping south through the area,
and/or the presence of outflow boundaries, and expected arrival of
a weak upper wave Wednesday, feel a mention of VCSH or VCTS if
warranted. Confidence in timing of any precipitation is too low to
go with a tempo or predominant period. If convection were to
impact a terminal directly, lower than VFR conditions are
possible. Winds through the period should be light/variable away
from any convection with weak boundaries in the vicinity.
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...GEELHART
SHORT TERM...HJS
LONG TERM...AUTEN
AVIATION...BAK
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
307 AM CDT WED AUG 27 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 202 AM CDT WED AUG 27 2014
SUBTLE UPPER LEVEL DISTURBANCES EMBEDDED IN A SOUTHWEST FLOW WILL
CROSS THE CENTRAL PLAINS OVER THE NEXT 36 TO 48 HOURS AS THE MAIN
UPPER LEVEL TROUGH MOVES SLOWLY EAST ACROSS THE FOUR CORNERS
REGION. EARLIER THIS MORNING THE WATER VAPOR LOOP, AND 00Z
WEDNESDAY UPPER AIR ANALYSIS PLACED ONE OF THE UPPER WAVES WERE
LOCATED OVER NORTHEAST NEW MEXICO. RADAR MOSAIC AND SURFACE
OBSERVATION INDICATED SCATTERED SHOWERS AND THUNDERSTORMS WERE
OCCURRING AHEAD OF THIS FEATURE ACROSS THE OKLAHOMA AND TEXAS
PANHANDLE. NAM, GFS, AND HRRR WERE ALL IN GOOD AGREEMENT IN MOVING
THIS AREA OF PRECIPITATION ACROSS WESTERN KANSAS DURING THE EARLY
MORNING HOURS AND BASED ON 06Z VERIFICATION OF THE UPPER WAVE AND
AREA FAVORABLE FOR PRECIPITATION THESE MODELS APPEAR TO HAVE A
GOOD HANDLE ON THIS EARLY MORNING EVENT. WILL THEREFORE KEEP HIGH
CHANCE OR EVEN LIKELY WORDING FOR THUNDERSTORMS THROUGH AT LEAST
15Z ACROSS NORTH CENTRAL AND MUCH OF WESTERN KANSAS AS THE UPPER
WAVE PASSES.
AS THIS FIRST SYSTEM LIFTS NORTHEAST TOWARDS SOUTHERN NEBRASKA
LATER THIS MORNING...A SECOND UPPER LEVEL DISTURBANCE WILL BEGIN
TO APPROACH THE AREA FROM THE SOUTHWEST. THIS NEXT SYSTEM APPEARS
TO BE LOCATED NEAR THE NOSE OF AN 300MB JET STREAK AND IS
CURRENTLY FORECAST TO CROSS WESTERN KANSAS LATE THIS AFTERNOON AND
EARLY THIS EVENING. GIVEN THE LOCATION OF AN UPPER LEVEL JET LATE
TODAY/EARLY EVENING ALONG WITH MOISTURE, AND INSTABILITY AHEAD OF
THIS NEXT DISTURBANCE WILL INCREASE PRECIPITATION CHANCES DURING
THE AFTERNOON AND EARLY EVENING. MAIN HAZARD CURRENTLY APPEARS TO
BE PERIODS OF HEAVY RAINFALL, HOWEVER A FEW OF THE STRONGER
THUNDERSTORMS IN WEST CENTRAL AND PARTS OF NORTH CENTRAL KANSAS
MAY ALSO PRODUCE HAIL AND STRONG GUSTY WINDS.
AS FOR TEMPERATURES TODAY WILL UNDERCUT GUIDANCE AND TREND
TOWARDS WHAT THE 850MB 00Z THURSDAY MIX DOWN TEMPERATURES
SUGGESTED FOR HIGHS. GIVEN THE EXPECTED CLOUD COVER AND THE 00Z
850MB TEMPERATURES WILL FAVOR AFTERNOON TEMPERATURES MAINLY IN THE
MID 80S ACROSS WEST CENTRAL KANSAS AND UPPER 80S TO NEAR 90
ELSEWHERE. IN SOUTH CENTRAL KANSAS WHERE MORE SUN AND LESS CLOUDS
ARE EXPECTED WILL TREND SLIGHTLY WARMER.
.LONG TERM...(THURSDAY THROUGH TUESDAY)
ISSUED AT 306 AM CDT WED AUG 27 2014
AN UPPER LEVEL LOW WILL MOVE THROUGH THE CENTRAL ROCKIES THURSDAY
THEN THROUGH THE CENTRAL PLAINS FRIDAY BEFORE WEAKENING AND
EXITING INTO THE UPPER MISSISSIPPI VALLEY ON SATURDAY. THIS
FEATURE WILL HELP PUSH A SURFACE COLD FRONT THROUGH WESTERN KANSAS
THURSDAY INTO THURSDAY NIGHT. THE FRONT WILL THEN BE POSITIONED
ACROSS CENTRAL KANSAS ON FRIDAY. LOWER AND MID LEVELS OF THE
ATMOSPHERE WILL BE SATURATED AND WITH THE LIFT CREATED BY THIS
SYSTEM, MOSTLY CLOUDY SKIES ARE EXPECTED THROUGH FRIDAY. STORM
CHANCES WILL ALSO BE PRESENT THROUGH FRIDAY WITH THE BEST CHANCE
OCCURRING THURSDAY AFTERNOON INTO THURSDAY NIGHT WHEN THE COLD
FRONT MOVES ACROSS THE CWA. THUNDERSTORM CHANCES END FROM WEST TO
EAST ON FRIDAY THEN BE CONFINED ACROSS CENTRAL AND EASTERN KANSAS
BY SATURDAY. A DRIER PERIOD IS THEN EXPECTED THROUGH THIS WEEKEND
INTO THE BEGINNING OF NEXT WEEK AS A WEAK UPPER LEVEL RIDGE MOVING
THROUGH THE ROCKIES AND HIGH PRESSURE BUILDING ACROSS THE AREA AT
THE SURFACE. MEANWHILE, A UPPER LEVEL LONG WAVE TROUGH IS PROGGED
TO DIG INTO THE PACIFIC NORTHWEST AND INTER-MOUNTAIN WEST THIS
WEEKEND INTO THE FIRST PART OF NEXT WEEK, THEN MOVE INTO THE THE
NORTHERN PLAINS BY MID WEEK. THIS COULD BRING A CHANCE OF
THUNDERSTORMS TUESDAY INTO WEDNESDAY, HOWEVER, IT IS TOO FAR OUT
TO PIN POINT EXACTLY THE BEST LIFT WILL OCCUR. OTHERWISE EXPECT
PARTLY CLOUDY SKIES SATURDAY THROUGH THE MIDDLE OF NEXT WEEK. AS
FOR TEMPERATURES, HIGHS LOOK TO BE IN THE 80S THURSDAY THROUGH
SATURDAY THEN INCREASE INTO THE LOWER TO MID 90S ON SUNDAY. HIGHS
MONDAY THROUGH WEDNESDAY ARE FORECASTED TO RANGE FROM THE UPPER
80S ACROSS WEST CENTRAL KANSAS TO MID 90S ACROSS SOUTH CENTRAL
KANSAS. LOWS THROUGH THE EXTENDED PERIOD LOOK TO GENERALLY BE IN
THE 60S WITH A FEW LOWER 70S ACROSS SOUTH CENTRAL KANSAS MONDAY
AND TUESDAY MORNINGS.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z WEDNESDAY NIGHT)
ISSUED AT 1208 AM CDT WED AUG 27 2014
WATER VAPOR LOOP AND 00Z UPPER AIR ANALYSIS INDICATING AT LEAST
TWO SUBTLE UPPER LEVEL WAVES WILL BE CROSSING SOUTHWEST KANSAS
OVER THE NEXT 18 TO 24 HOURS. FIRST OF THESE TWO SYSTEMS WILL
CROSS SOUTHWEST KANSAS LATE TONIGHT/EARLY WEDNESDAY. THE SECOND
WILL CROSS WESTERN KANSAS DURING THE AFTERNOON/EARLY EVENING.
BASED ON THE MOISTURE AND LIFT AHEAD OF THESE TWO UPPER LEVEL
DISTURBANCES THERE WILL BE A CHANCE THUNDERSTORMS IN ALL THREE
TAFS EARLY THIS MORNING AND AGAIN LATER THIS AFTERNOON/EVENING.
00Z NAM BUFR SOUNDINGS INDICATING THE CLOUD BASES THROUGH
WEDNESDAY AFTERNOON WILL BE AT OR ABOVE THE 3000FT AGL LEVEL.
GUSTY WINDS WINDS WILL BE POSSIBLE FROM ANY THUNDERSTORM EARLY
THIS MORNING OR LATER THIS AFTERNOON, HOWEVER THE PREVAILING WINDS
WILL BE SOUTHERLY AT 10 KNOTS OR LESS THROUGH EARLY WEDNESDAY
MORNING. GUSTY SOUTH/SOUTHEAST WINDS AT AROUND 15 KNOTS WILL
DEVELOP BY LATE MORNING.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 88 67 86 64 / 30 50 50 50
GCK 85 66 84 63 / 50 60 40 40
EHA 85 64 83 62 / 40 50 40 40
LBL 88 67 86 65 / 40 50 40 40
HYS 87 68 85 66 / 50 60 50 50
P28 92 71 88 68 / 20 40 60 60
&&
.DDC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...BURGERT
LONG TERM...HOVORKA_42
AVIATION...BURGERT
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
203 AM CDT WED AUG 27 2014
...UPDATED SHORT TERM DISCUSSION
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 202 AM CDT WED AUG 27 2014
SUBTLE UPPER LEVEL DISTURBANCES EMBEDDED IN A SOUTHWEST FLOW WILL
CROSS THE CENTRAL PLAINS OVER THE NEXT 36 TO 48 HOURS AS THE MAIN
UPPER LEVEL TROUGH MOVES SLOWLY EAST ACROSS THE FOUR CORNERS
REGION. EARLIER THIS MORNING THE WATER VAPOR LOOP, AND 00Z
WEDNESDAY UPPER AIR ANALYSIS PLACED ONE OF THE UPPER WAVES WERE
LOCATED OVER NORTHEAST NEW MEXICO. RADAR MOSAIC AND SURFACE
OBSERVATION INDICATED SCATTERED SHOWERS AND THUNDERSTORMS WERE
OCCURRING AHEAD OF THIS FEATURE ACROSS THE OKLAHOMA AND TEXAS
PANHANDLE. NAM, GFS, AND HRRR WERE ALL IN GOOD AGREEMENT IN MOVING
THIS AREA OF PRECIPITATION ACROSS WESTERN KANSAS DURING THE EARLY
MORNING HOURS AND BASED ON 06Z VERIFICATION OF THE UPPER WAVE AND
AREA FAVORABLE FOR PRECIPITATION THESE MODELS APPEAR TO HAVE A
GOOD HANDLE ON THIS EARLY MORNING EVENT. WILL THEREFORE KEEP HIGH
CHANCE OR EVEN LIKELY WORDING FOR THUNDERSTORMS THROUGH AT LEAST
15Z ACROSS NORTH CENTRAL AND MUCH OF WESTERN KANSAS AS THE UPPER
WAVE PASSES.
AS THIS FIRST SYSTEM LIFTS NORTHEAST TOWARDS SOUTHERN NEBRASKA
LATER THIS MORNING...A SECOND UPPER LEVEL DISTURBANCE WILL BEGIN
TO APPROACH THE AREA FROM THE SOUTHWEST. THIS NEXT SYSTEM APPEARS
TO BE LOCATED NEAR THE NOSE OF AN 300MB JET STREAK AND IS
CURRENTLY FORECAST TO CROSS WESTERN KANSAS LATE THIS AFTERNOON AND
EARLY THIS EVENING. GIVEN THE LOCATION OF AN UPPER LEVEL JET LATE
TODAY/EARLY EVENING ALONG WITH MOISTURE, AND INSTABILITY AHEAD OF
THIS NEXT DISTURBANCE WILL INCREASE PRECIPITATION CHANCES DURING
THE AFTERNOON AND EARLY EVENING. MAIN HAZARD CURRENTLY APPEARS TO
BE PERIODS OF HEAVY RAINFALL, HOWEVER A FEW OF THE STRONGER
THUNDERSTORMS IN WEST CENTRAL AND PARTS OF NORTH CENTRAL KANSAS
MAY ALSO PRODUCE HAIL AND STRONG GUSTY WINDS.
AS FOR TEMPERATURES TODAY WILL UNDERCUT GUIDANCE AND TREND
TOWARDS WHAT THE 850MB 00Z THURSDAY MIX DOWN TEMPERATURES
SUGGESTED FOR HIGHS. GIVEN THE EXPECTED CLOUD COVER AND THE 00Z
850MB TEMPERATURES WILL FAVOR AFTERNOON TEMPERATURES MAINLY IN THE
MID 80S ACROSS WEST CENTRAL KANSAS AND UPPER 80S TO NEAR 90
ELSEWHERE. IN SOUTH CENTRAL KANSAS WHERE MORE SUN AND LESS CLOUDS
ARE EXPECTED WILL TREND SLIGHTLY WARMER.
.LONG TERM...(WEDNESDAY NIGHT THROUGH TUESDAY)
ISSUED AT 120 PM CDT TUE AUG 26 2014
MEDIUM RANGE MODELS INDICATE AN UPPER LEVEL TROUGH OF LOW PRESSURE
PUSHING EASTWARD OUT OF THE CENTRAL AND SOUTHERN ROCKIES INTO THE
WESTERN HIGH PLAINS THURSDAY BRINGING ADDITIONAL PRECIP CHANCES TO
PORTIONS OF WESTERN AND CENTRAL KANSAS EARLY IN THE PERIOD. AS
THE UPPER LEVEL SHORTWAVE KICKS OUT OF THE ROCKIES, A PREVAILING
SURFACE TROUGH ACROSS EASTERN COLORADO WILL BEGIN TO SHIFT
EASTWARD INTO EXTREME WESTERN KANSAS PROVIDING INCREASED
CONVERGENCE ACROSS THE AREA. MEANWHILE, AMPLE MOISTURE WILL
CONTINUE TO POOL AHEAD OF THE ADVANCING SURFACE TROUGH WITHIN A
SOUTHEASTERLY UPSLOPE FLOW WITH H85 DEWPOINTS UP NEAR 15C.
ADDITIONALLY, A +70KT UPPER LEVEL JET LIFTING NORTHEAST OUT OF THE
APPROACHING TROUGH AXIS, IS PROJECTED TO MOVE EASTWARD ACROSS
WESTERN KANSAS TOWARD THURSDAY AFTERNOON. AS LOW/MID LEVEL LAPSE
RATES STEEPEN THURSDAY AFTERNOON, THUNDERSTORMS WILL BE POSSIBLE
ACROSS CENTRAL AND PORTIONS OF WESTERN KANSAS AHEAD OF THE SURFACE
TROUGH IN A CORRIDOR OF INCREASED INSTABILITY. ALTHOUGH WIDESPREAD
SEVERE WEATHER IS NOT EXPECTED, ENOUGH DEEP LAYER SHEAR AND
INSTABILITY WILL BE PRESENT TO SUPPORT THE POTENTIAL FOR STRONG
TO MARGINALLY SEVERE STORMS.
THE FOCUS FOR PRECIP SHIFTS EASTWARD MORE INTO CENTRAL AND EASTERN
KANSAS FRIDAY AS THE SURFACE TROUGH MIGRATES FURTHER EAST. DRIER
CONDITIONS WILL RETURN TO WESTERN KANSAS OVER THE WEEKEND AS THE
UPPER LEVEL SHORTWAVE PUSHES FURTHER EAST INTO THE MISSISSIPPI
RIVER VALLEY WHILE WEAK RIDGING ALOFT MOVES OUT OF THE ROCKIES
INTO THE WESTERN HIGH PLAINS.
NEAR NORMAL TEMPERATURES ARE EXPECTED THURSDAY EVEN AS THE SURFACE
TROUGH PUSHES ACROSS WESTERN KANSAS THROUGHOUT THE DAY. THE GFS AND
ECMWF SHOW H85 TEMPERATURES GENERALLY AROUND 20C ACROSS CENTRAL AND
SOUTHWEST KANSAS WITH THE WARMEST AIR IN PLACE ACROSS SOUTH
CENTRAL KANSAS AHEAD OF THE TROUGH. LOOK FOR HIGHS WELL UP INTO
THE 80S(F) THURSDAY AFTERNOON WITH NEAR 90F STILL POSSIBLE IN
SOUTH CENTRAL KANSAS. SLIGHTLY COOLER TEMPERATURES ARE LIKELY
FRIDAY AS A NORTHERLY FLOW SETS UP BEHIND THE DEPARTING SURFACE
TROUGH. COOLER AIR WILL FILTER SOUTHWARD INTO CENTRAL AND WESTERN
KANSAS AS A RESULT WITH H85 TEMPERATURES DROPPING BELOW 20C NEAR
THE I-70 CORRIDOR. HIGHS ONLY UP INTO THE LOWER TO MID 80S(F) ARE
EXPECTED FRIDAY AFTERNOON. TEMPERATURES WILL REBOUND SOMEWHAT INTO
THE WEEKEND AS THE AFOREMENTIONED WEAK UPPER LEVEL RIDGE TRANSITIONS
EAST ACROSS THE CENTRAL PLAINS.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z WEDNESDAY NIGHT)
ISSUED AT 1208 AM CDT WED AUG 27 2014
WATER VAPOR LOOP AND 00Z UPPER AIR ANALYSIS INDICATING AT LEAST
TWO SUBTLE UPPER LEVEL WAVES WILL BE CROSSING SOUTHWEST KANSAS
OVER THE NEXT 18 TO 24 HOURS. FIRST OF THESE TWO SYSTEMS WILL
CROSS SOUTHWEST KANSAS LATE TONIGHT/EARLY WEDNESDAY. THE SECOND
WILL CROSS WESTERN KANSAS DURING THE AFTERNOON/EARLY EVENING.
BASED ON THE MOISTURE AND LIFT AHEAD OF THESE TWO UPPER LEVEL
DISTURBANCES THERE WILL BE A CHANCE THUNDERSTORMS IN ALL THREE
TAFS EARLY THIS MORNING AND AGAIN LATER THIS AFTERNOON/EVENING.
00Z NAM BUFR SOUNDINGS INDICATING THE CLOUD BASES THROUGH
WEDNESDAY AFTERNOON WILL BE AT OR ABOVE THE 3000FT AGL LEVEL.
GUSTY WINDS WINDS WILL BE POSSIBLE FROM ANY THUNDERSTORM EARLY
THIS MORNING OR LATER THIS AFTERNOON, HOWEVER THE PREVAILING WINDS
WILL BE SOUTHERLY AT 10 KNOTS OR LESS THROUGH EARLY WEDNESDAY
MORNING. GUSTY SOUTH/SOUTHEAST WINDS AT AROUND 15 KNOTS WILL
DEVELOP BY LATE MORNING.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 92 68 87 66 / 60 50 50 50
GCK 90 66 85 63 / 40 50 50 40
EHA 89 64 84 62 / 40 50 50 40
LBL 92 67 87 64 / 40 50 50 40
HYS 91 68 86 66 / 60 60 50 50
P28 96 71 89 69 / 30 50 60 60
&&
.DDC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...BURGERT
LONG TERM...JJOHNSON
AVIATION...BURGERT
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
520 AM EDT WED AUG 27 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 349 AM EDT WED AUG 27 2014
MUCH OF THE FOCUS OF THE SHORT TERM FORECAST IS WITH THE SHORTWAVE
QUICKLY MOVING EAST-SOUTHEAST INTO THE UPPER GREAT LAKES REGION.
THE AXIS OF THE SHORTWAVE IS LOCATED IN NORTHERN MINNESOTA AT
07Z...BUT THERE ARE TWO AREAS OF SHOWERS AHEAD OF THIS WAVE...ONE
STRETCHING FROM ISLE ROYALE TO LITTLE FALLS MINNESOTA AND THE OTHER
FROM WESTERN MARQUETTE COUNTY TO EAU CLAIRE WISCONSIN. EVEN THOUGH
THE 00Z KMPX RAOB INDICATED DRY AIR BELOW THE CLOUDS BASE...RAIN
HAS BEEN REACHING THE GROUND UNDER MOST OF THE RADAR RETURNS AND
GENERALLY PRODUCING ANYWHERE FROM A TRACE TO 0.05IN OF RAIN AS IT
HAS MOVED THROUGH MINNESOTA AND NORTHWEST WISCONSIN. EXPECT THESE
SHOWERS TO CONTINUE TO THE EAST AS THE SHORTWAVE QUICKLY MOVES
THROUGH THE WEST HALF OF UPPER MICHIGAN BY 12Z AND OUT OF THE ENTIRE
AREA BY 15Z. THE 04Z/05Z HRRR RUNS HAVE HAD A DECENT HANDLE ON
PRECIP AND WEIGHTED THE POP FORECAST TOWARDS THAT FOR THE FIRST
6HRS. THEREFORE...HAVE SHOWN SCATTERED/ISOLATED SHOWERS MOVING
THROUGH THE CWA THIS MORNING AND QUICKLY COMING TO AN END FROM WEST
TO EAST. BEHIND THE SHORTWAVE...DRY AIR ASSOCIATED WITH A HIGH
CURRENTLY CENTERED IN MINNESOTA WILL QUICKLY MOVE OVER MUCH OF THE
AREA AND LEAD TO ANOTHER COOL DAY ACROSS THE U.P.
EXPECT SOME DIURNAL CLOUD DEVELOPMENT AFTER THE MID CLOUDS
DEPART...AS A POCKET OF MOISTURE AROUND 850MB OR 4KFT SEEN OVER LAKE
SUPERIOR THIS PAST EVENING AND KCMX OBS OVERNIGHT GRADUALLY SHIFTS
SOUTHEAST AND DISSIPATES. WITH THE LIGHT WEST-NORTHWEST FLOW IN THE
LOW LEVELS...EXPECT THE CLOUDS TO BE INLAND FROM LAKE SUPERIOR AND
GENERALLY OVER CENTRAL/EASTERN UPPER MICHIGAN. HIGHS TODAY WILL BE
SIMILAR TO YESTERDAY OVER THE WEST THIRD (MID-UPPER 60S) AND
SLIGHTLY COOLER OVER THE CENTRAL/EAST (65-71).
HIGH PRESSURE WILL REMAIN IN PLACE TONIGHT AND PRODUCE MOSTLY CLEAR
SKIES (JUST A FEW HIGH CLOUDS APPROACHING FROM THE SOUTHWEST AHEAD
OF THE NEXT SHORTWAVE). THE MOSTLY CLEAR SKIES...LIGHT WINDS...AND
PWATS AROUND 45 PERCENT OF NORMAL WILL LEAD TO A GOOD RADIATIONAL
COOLING NIGHT. HAVE THE INTERIOR LOCATIONS FALLING INTO THE LOWER
40S TO UPPER 30S...WHICH IS A LITTLE COOLER THAN THE PREVIOUS
FORECAST. WOULD NOT BE SURPRISED IF SOME OF THE TRADITIONAL COLD
RAWS SITES REACH THE MIDDLE 30S AND DID DROP A FEW OF THEM TO THOSE
VALUES (WHICH COULD LEAD TO SOME PATCHY FROST). WILL CONTINUE THE
MENTION OF PATCHY RADIATIONAL/GROUND FOG FOR TONIGHT...BUT DON/T
EXPECT IT TO BE TOO THICK DUE TO THE EXISTING DRY AIR. THE PLACES
WHERE IT SHOULD BE THE THICKEST WOULD BE IN ANY LOW SPOTS OR NEAR
LAKES (DUE TO THEIR WARMER WATER TEMPERATURES).
.LONG TERM...(THURSDAY THROUGH TUESDAY)
ISSUED AT 519 AM EDT WED AUG 27 2014
THRU THE BEGINNING OF THE UPCOMING WEEKEND...A LOW AMPLITUDE
PROGRESSIVE NRN STREAM FLOW REGIME WILL PREVAIL ACROSS SRN CANADA. A
WEAKER SRN BRANCH FLOW ACROSS THE CONUS WILL CAUSE ISSUES WITH
REGARD TO PCPN OVER THE UPPER LAKES...DEPENDING ON INTERACTION OF
SHORTWAVES WITH THE MORE PROGRESSIVE FLOW TO THE N. RIGHT NOW...THE
SRN BRANCH FEATURES A TROF AND WELL-DEFINED SHORTWAVE OVER THE SRN
ROCKIES. EARLY NEXT WEEK...FLOW WILL AMPLIFY SOME AS A MORE
SUBSTANTIAL TROF MOVES INTO THE NW CONUS AND THEN SHIFTS EASTWARD.
OVERALL...THIS PATTERN WILL SUPPORT TEMPS GENERALLY AROUND NORMAL TO
A BIT BLO OVER THE NEXT FEW DAYS. BRIEF WARMING WILL OCCUR EARLY
NEXT WEEK AHEAD OF THE MORE SUBSTANTIAL TROF PROGRESSING E ACROSS
THE NW AND NCNTRL CONUS. PCPN FCST IS QUITE UNCERTAIN. THERE IS THE
POTENTIAL FOR AT LEAST A COUPLE OF ROUNDS OF PCPN THRU THE UPCOMING
WEEKEND...DEPENDING ON EVOLUTION OF SRN BRANCH SHORTWAVES. ANOTHER
PERIOD OF PCPN SHOULD OCCUR EARLY NEXT WEEK AS COLD FRONT SWEEPS
ACROSS THE AREA IN ASSOCIATION WITH AFOREMENTIONED TROF MOVING
ACROSS THE NW/NCNTRL CONUS.
BEGINNING THU/FRI...ATTENTION TURNS TO SHORTWAVE LIFTING OUT OF THE
SRN BRANCH TROF CURRENTLY OVER THE SRN ROCKIES. WITH NRN STREAM
TROFS MOVING ACROSS THE CANADIAN ROCKIES AND QUEBEC/NEW ENGLAND...
THERE WILL BE AN OPPORTUNITY FOR THE SRN BRANCH SHORTWAVE TO MAKE
SOME NORTHWARD PROGRESS. MODELS HAVE OVERALL MOVED INTO BETTER
AGREEMENT ON WAA/MOISTURE ADVECTION LIFTING N AND SPREADING PCPN
INTO UPPER MI THU NIGHT/FRI. HOWEVER...THERE ARE STILL SOME
DIFFERENCES AS THE GEM/ECMWF/NAM ARE MORE AGGRESSIVE SPREADING MAIN
AREA OF PCPN MORE SQUARELY ACROSS THE FCST AREA. THE GFS IS FOCUSED
MORE TO THE S AND E. GIVEN TRENDS AND GFS SOMEWHAT ON ITS OWN...
RAISED POPS SOME FOR LATER THU NIGHT/FRI MORNING WITH LIKELY POPS
FROM THE SCNTRL TO THE ERN FCST AREA. WILL NEED TO CONTINUE UPWARD
TREND IF NEXT ROUND OF MODELS STAYS ON TRACK. INSTABILITY IS RATHER
LIMITED. ONLY INCLUDED THUNDER SCNTRL AND E. AFTER SOME PATCHY FOG
EARLY THU...SUNSHINE WILL GIVE WAY TO INCREASING HIGH CLOUDS. MIXING
TO 850-800MB ON FCST SOUNDINGS SUGGEST HIGH TEMPS THU WILL BE MOSTLY
IN THE LOW/MID 70S AWAY FROM LAKE COOLING.
OVER THE WEEKEND...FCST HAS BECOME MORE UNCERTAIN AS THERE IS A
TREND FOR THE MAIN ENERGY CURRENTLY IN THE SRN ROCKIES TROF TO LIFT
FARTHER N. ASSOCIATED WEAK SFC WAVE IS FCST TO TRACK ACROSS SRN WI
AND THRU NRN LWR MI. GIVEN TRENDS ALONG WITH DECENT AGREEMENT AMONG
00Z MEDIUM RANGE GUIDANCE...WILL LINGER CHC POPS OVER THE SE HALF OF
THE FCST AREA FRI NIGHT...THEN SPREAD CHC POPS BACK N AND W SAT/SAT
NIGHT. LOOKS LIKE SUN SHOULD DRY OUT WITH SHORTWAVE RIDGE ARRIVING
BTWN DEPARTING SHORTWAVE AND AHEAD OF MORE SIGNIFICANT TROF
DEVELOPING INTO THE NW CONUS.
AS THE MORE SUBSTANTIAL TROF OVER THE NW CONUS SHIFTS EASTWARD EARLY
NEXT WEEK...A COLD FRONT WILL SWEEP E ACROSS THE GREAT LAKES...
BRINGING A DECENT POTENTIAL FOR SHRA/TSRA. FOR THIS FAR OUT IN THE
MODEL RUNS...AGREEMENT IS GOOD ON TIMING FRONT. THE ECMWF HAS
NOTABLY TRENDED FASTER TOWARD THE GFS WHICH IS TYPICALLY MORE
PROGRESSIVE...AND THE GEM OFFERS SIMILAR TIMING. THESE LATEST RUNS
SUGGEST FRONT CROSSING UPPER MI MON AFTN/NIGHT. SO IT LOOKS LIKE
LABOR DAY MIGHT TURN WET WITH SHRA AND TSTMS SPREADING E ACROSS THE
AREA.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z WEDNESDAY NIGHT)
ISSUED AT 122 AM EDT WED AUG 27 2014
MID-LEVEL CLOUDS WILL INCREASE FOR A TIME OVERNIGHT UNTIL AROUND
DAYBREAK ON WEDNESDAY AS A DISTURBANCE CROSSES THE REGION. ALTHOUGH
A FEW SPRINKLES MAY BE POSSIBLE...ESPECIALLY AT IWD...LOW LEVELS
WILL REMAIN DRY ENOUGH SO THAT VFR CONDITIONS WILL PREVAIL. THE MID
CLOUDS ARE EXPECTED TO MOVE OUT BY LATE MORNING INTO THE AFTERNOON
IN THE WAKE OF THE DISTURBANCE.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 349 AM EDT WED AUG 27 2014
HIGH PRESSURE MOVING THROUGH THE UPPER GREAT LAKES REGION TODAY AND
THURSDAY WILL LEAD TO WINDS STAYING BELOW 15KTS. THIS HIGH WILL
SHIFT EAST THURSDAY NIGHT...ALLOWING A COUPLE WEAK SURFACE TROUGHS
TO MOVE THROUGH THE REGION. THE WEAK PRESSURE GRADIENT ASSOCIATED
WITH THESE TROUGHS WILL KEEP WINDS BELOW 20KTS.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...SRF
LONG TERM...ROLFSON
AVIATION...JLB
MARINE...SRF
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
350 AM EDT WED AUG 27 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 349 AM EDT WED AUG 27 2014
MUCH OF THE FOCUS OF THE SHORT TERM FORECAST IS WITH THE SHORTWAVE
QUICKLY MOVING EAST-SOUTHEAST INTO THE UPPER GREAT LAKES REGION.
THE AXIS OF THE SHORTWAVE IS LOCATED IN NORTHERN MINNESOTA AT
07Z...BUT THERE ARE TWO AREAS OF SHOWERS AHEAD OF THIS WAVE...ONE
STRETCHING FROM ISLE ROYALE TO LITTLE FALLS MINNESOTA AND THE OTHER
FROM WESTERN MARQUETTE COUNTY TO EAU CLAIRE WISCONSIN. EVEN THOUGH
THE 00Z KMPX RAOB INDICATED DRY AIR BELOW THE CLOUDS BASE...RAIN
HAS BEEN REACHING THE GROUND UNDER MOST OF THE RADAR RETURNS AND
GENERALLY PRODUCING ANYWHERE FROM A TRACE TO 0.05IN OF RAIN AS IT
HAS MOVED THROUGH MINNESOTA AND NORTHWEST WISCONSIN. EXPECT THESE
SHOWERS TO CONTINUE TO THE EAST AS THE SHORTWAVE QUICKLY MOVES
THROUGH THE WEST HALF OF UPPER MICHIGAN BY 12Z AND OUT OF THE ENTIRE
AREA BY 15Z. THE 04Z/05Z HRRR RUNS HAVE HAD A DECENT HANDLE ON
PRECIP AND WEIGHTED THE POP FORECAST TOWARDS THAT FOR THE FIRST
6HRS. THEREFORE...HAVE SHOWN SCATTERED/ISOLATED SHOWERS MOVING
THROUGH THE CWA THIS MORNING AND QUICKLY COMING TO AN END FROM WEST
TO EAST. BEHIND THE SHORTWAVE...DRY AIR ASSOCIATED WITH A HIGH
CURRENTLY CENTERED IN MINNESOTA WILL QUICKLY MOVE OVER MUCH OF THE
AREA AND LEAD TO ANOTHER COOL DAY ACROSS THE U.P.
EXPECT SOME DIURNAL CLOUD DEVELOPMENT AFTER THE MID CLOUDS
DEPART...AS A POCKET OF MOISTURE AROUND 850MB OR 4KFT SEEN OVER LAKE
SUPERIOR THIS PAST EVENING AND KCMX OBS OVERNIGHT GRADUALLY SHIFTS
SOUTHEAST AND DISSIPATES. WITH THE LIGHT WEST-NORTHWEST FLOW IN THE
LOW LEVELS...EXPECT THE CLOUDS TO BE INLAND FROM LAKE SUPERIOR AND
GENERALLY OVER CENTRAL/EASTERN UPPER MICHIGAN. HIGHS TODAY WILL BE
SIMILAR TO YESTERDAY OVER THE WEST THIRD (MID-UPPER 60S) AND
SLIGHTLY COOLER OVER THE CENTRAL/EAST (65-71).
HIGH PRESSURE WILL REMAIN IN PLACE TONIGHT AND PRODUCE MOSTLY CLEAR
SKIES (JUST A FEW HIGH CLOUDS APPROACHING FROM THE SOUTHWEST AHEAD
OF THE NEXT SHORTWAVE). THE MOSTLY CLEAR SKIES...LIGHT WINDS...AND
PWATS AROUND 45 PERCENT OF NORMAL WILL LEAD TO A GOOD RADIATIONAL
COOLING NIGHT. HAVE THE INTERIOR LOCATIONS FALLING INTO THE LOWER
40S TO UPPER 30S...WHICH IS A LITTLE COOLER THAN THE PREVIOUS
FORECAST. WOULD NOT BE SURPRISED IF SOME OF THE TRADITIONAL COLD
RAWS SITES REACH THE MIDDLE 30S AND DID DROP A FEW OF THEM TO THOSE
VALUES (WHICH COULD LEAD TO SOME PATCHY FROST). WILL CONTINUE THE
MENTION OF PATCHY RADIATIONAL/GROUND FOG FOR TONIGHT...BUT DON/T
EXPECT IT TO BE TOO THICK DUE TO THE EXISTING DRY AIR. THE PLACES
WHERE IT SHOULD BE THE THICKEST WOULD BE IN ANY LOW SPOTS OR NEAR
LAKES (DUE TO THEIR WARMER WATER TEMPERATURES).
.LONG TERM...(WEDNESDAY NIGHT THROUGH TUESDAY)
ISSUED AT 352 PM EDT TUE AUG 26 2014
AS HAS BEEN THE CASE THE LAST SEVERAL DAYS...FCST CONCERNS IN THE
MIDDLE/LONGER TERM WL FOCUS ON THE INTERACTION BTWN A FAIRLY ZONAL
NRN BRANCH FLOW OVER SRN CANADA/A WEAKER SRN BRANCH FLOW OVER THE
CONUS AND POTENTIAL FOR PCPN ACRS UPR MI. THE BULK OF THE LATEST
MODEL GUIDANCE HINTS THE SE CWA WL BE IMPACTED MOST BY WAVES
REMAINING MAINLY IN THE SRN BRANCH. NEAR SEASONABLE TEMPS INTO THE
WEEKEND WL GIVE WAY TO WARMER WX EARLY NEXT WEEK AND SOME SHOWERS/TS
LATER ON LABOR DAY AS A STRONG COLD FNT APRCHS THE AREA.
WED NGT...SFC HI PRES IN ADVANCE OF SHRTWV RDG WITHIN NRN BRANCH
FLOW WL BRING MOCLR SKIES AND LGT WINDS. SOME HI CLDS MAY BEGIN TO
FILTER INTO THE SW CWA LATE AT NGT AS THE SFC HI SHIFTS TO THE E AND
A BIT OF A RETURN SLY FLOW BEGINS TO DVLP IN ADVANCE OF SHRTWV
EMBEDDED IN WEAKER SRN BRANCH THAT WL BE SHIFTING THRU THE NCENTRAL
PLAINS. EXPECT THE LOWEST MIN TEMPS OVER THE INTERIOR E AND CENTRAL
CLOSER TO THE CORE OF THE HI PRES/PWAT AS LO AS 0.50 INCH OR ABOUT
50 PCT OF NORMAL. PREVIOUS FCST TEMPS APPEAR ON TRACK. MAINTAINED
MENTION OF PATCHY FOG IN THIS AREA.
THU THRU SAT...NOT SURPRISINGLY...MODEL FCST DIFFERENCES BECOME MORE
APRNT REGARDING THE POTENTIAL INTERACTION BTWN THE STRONGER NRN
BRANCH FLOW IN SRN CANADA/WEAKER FLOW OVER THE CONUS AND HOW QUICKLY
AND HOW FAR N PCPN WL SPREAD IN ADVANCE OF A DISTURBANCE RIPPLING
THRU THE SRN BRANCH FM THE NCENTRAL PLAINS TOWARD THE UPR MIDWEST/
GREAT LKS AND WHEN/HOW QUICKLY ANY PCPN WOULD EXIT THE AREA. FOR
INSTANCE...THE 00Z CNDN MODEL WAS MUCH FASTER AT BRINGING PCPN INTO
THE WRN CWA ON THU...BUT THIS MODEL SHOWED MORE PHASING BTWN THE
BRANCHES/A DEEPER SFC LO LIFTING NEWD THRU MN/SSW H85 WINDS UP TO 50
KTS AGGRESSIVELY RETURNING MSTR/HIER INSTABILITY INTO THE UPR LKS.
THIS MODEL THEN SHOWED MORE RAPID DRYING/SUBSIDENCE ON SAT BEHIND
THE STRONGER/MORE PHASED DISTURBANCE. GIVEN THE LACK OF MEANINGFUL
INTERACTION APRNT ON THE SEPARATE FCST H5 FLOWS AND THE SHIFT OF THE
12Z CNDN MODEL TOWARD THE OTHER MORE SUPPRESSED GUIDANCE...WL TEND
TOWARD A CONSENSUS OF THE 12Z GFS AND 00Z ECMWF THAT SHOW A RIBBON
OF HIER QPF OVER MAINLY THE SE CWA ON THE SE EDGE OF FCST CONFLUENCE
ZN IN THE H5 FLOW AND CLOSER TO MORE PERSISTENT SFC LO PRES TROF...
WHERE THE FCST PWAT REMAINS AS HI AS 1.50-2.00 INCHES. ON SAT...A
SHRTWV IN THE NRN BRANCH IS FCST TO SWING THRU NW ONTARIO...WITH
ATTENDANT COLD FNT CROSSING THE UPR LKS. BUT SINCE THE BULK OF THE
MSTR IS LIKELY TO REMAIN TO THE SE CLOSER TO SRN BRANCH DISTURBANCE
TRACK/SFC LO PRES TROF...SUSPECT THE FROPA WL BE RELATIVELY DRY.
HIER POPS WL REMAIN OVER THE SE CWA.
EXTENDED...BEST CHC FOR A DRY DAY APPEARS TO BE ON SUN...WHEN SFC HI
PRES IS FCST TO PASS THRU ONTARIO UNDER A SHRTWV RDG IN THE NRN
BRANCH. BUT SOME OF THE EXTENDED MODELS SHOWED A SLOWER SRN BRANCH
SHRTWV MOVING THRU LOWER MI BRINGING SOME PCPN INTO AT LEAST THE SE
CWA. SO FCST WL SHOW SOME LO CHC POPS OVER MAINLY THAT AREA. ON
LABOR DAY/TUE...STRENGTHENING SSW FLOW BTWN THE HI SHIFTING INTO
QUEBEC AND A FAIRLY STRONG DISTURBANCE/ATTENDANT COLD FNT MOVING
ACRS SRN CANADA WL BRING A RETURN OF WARMER...MOISTER AIR/GREATER
SHOWER AND TS CHCS. WL RELY ON THE MODEL CONSENSUS FOR FCST
PREPARATION.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z WEDNESDAY NIGHT)
ISSUED AT 122 AM EDT WED AUG 27 2014
MID-LEVEL CLOUDS WILL INCREASE FOR A TIME OVERNIGHT UNTIL AROUND
DAYBREAK ON WEDNESDAY AS A DISTURBANCE CROSSES THE REGION. ALTHOUGH
A FEW SPRINKLES MAY BE POSSIBLE...ESPECIALLY AT IWD...LOW LEVELS
WILL REMAIN DRY ENOUGH SO THAT VFR CONDITIONS WILL PREVAIL. THE MID
CLOUDS ARE EXPECTED TO MOVE OUT BY LATE MORNING INTO THE AFTERNOON
IN THE WAKE OF THE DISTURBANCE.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 349 AM EDT WED AUG 27 2014
HIGH PRESSURE MOVING THROUGH THE UPPER GREAT LAKES REGION TODAY AND
THURSDAY WILL LEAD TO WINDS STAYING BELOW 15KTS. THIS HIGH WILL
SHIFT EAST THURSDAY NIGHT...ALLOWING A COUPLE WEAK SURFACE TROUGHS
TO MOVE THROUGH THE REGION. THE WEAK PRESSURE GRADIENT ASSOCIATED
WITH THESE TROUGHS WILL KEEP WINDS BELOW 20KTS.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...SRF
LONG TERM...KC
AVIATION...JLB
MARINE...SRF
AREA FORECAST DISCUSSION
NWS ST LOUIS MO
244 AM CDT Wed Aug 27 2014
.SYNOPSIS:
Issued at 237 AM CDT Wed Aug 27 2014
Front is slowly making progress into the CWA early this morning
and is currently stretching from near Kansas City, Missouri to
Quincy, Illinois. Some isolated thunderstorms continue to pop up
here and there on outflow boundaries across eastern Missouri and
west central Illinois, with a better defined cluster of convection
now taking shape across far northwest Missouri. Temperatures
remain mild with all locations still in the 70s this morning.
CVKING
&&
.SHORT TERM: (Through Tonight)
Issued at 237 AM CDT Wed Aug 27 2014
Elevated convection will continue to develop across northern
Missouri early this morning with scattered thunderstorms forecast
through the lunch hour across the northern counties of the CWA.
Front will make very slow progress south today. Temperatures will
quickly rise into the 90s south of the front and due to pooled
dewpoints in the lower to middle 70s, produce at least a few hours
of heat indices above 100 degrees along and south of I-70. Although
it won`t be as hot as the past few days - feel current heat
headlines are warranted given potential for one more day of heat
indices reaching 105 degrees this afternoon.
The front will also serve as the focus for convective initiation
with scattered thunderstorms expected along and south of I-70 this
afternoon. As was the case yesterday, a few of the storms could
produce some gusty winds to 50 mph and torrential downpours.
Diurnal convection expected to dissipate quickly after sunset with
the focus for more elevated development shifting back north of the
boundary across the northern reaches of the CWA after midnight.
CVKING
.LONG TERM: (Thursday through Tuesday)
Issued at 237 AM CDT Wed Aug 27 2014
Boundary will be slow to lift back north on Thursday and may become
orientated more northwest to southeast across the CWA...paralleling
the Mississippi River. Once again, afternoon convection will be
possible in the vicinity of this front.
The boundary should finally lift north as a warm front Thursday
night with dry and seasonably warm weather expected on Friday
ahead of the shortwave/cold front that approaches from the west.
Have tried to focus likely POPs Friday night and Saturday with this
next system as blended guidance seems to give too long of a period
of POPs when compared to reality. So, after a wet and cooler
beginning to the Labor Day Weekend, it appears chances of
precipitation will decrease for Sunday and Monday (Labor Day), with
temperatures beginning to inch back up above normal in the wake
of this storm system.
CVKING
&&
.AVIATION: (For the 06z TAFs through 06z Wednesday Night)
Issued at 1054 PM CDT Tue Aug 26 2014
Cluster of storms northeast of the St Louis metro area will
likely slowly dissipate late tonight, although could not rule out
an isolated storm along the outflow boundary moving southwestward
through the St Louis metro. The surface wind will temporarily
switch to a northeast direction and pick up behind the outflow
boundary. A cold front was across northern MO, just south of UIN
this evening. This front will sag slowly southward late tonight
and Wednesday with scattered convection possible along and just
north of this front. Latest HRRR model run keeps UIN dry late
tonight, but there may be at least isolated showers/storms in the
UIN area late tonight into Wednesday morning. Due to uncertainty
in timing and coverage may keep the UIN taf dry for now. With
mostly light surface winds, mainly just high level clouds, and
high surface dew points there will likely be some fog late
tonight/early Wednesday morning mainly in SUS and CPS. The surface
wind will be mainly nely in UIN and COU Wednesday, and becoming
nely Wednesday afternoon in the St Louis metro area after fropa.
Specifics for KSTL: May need to include VCTS in the STL taf around
06-07z late tonight if storms develop along outflow boundary
dropping southwestward through STL. The wind will also briefly
switch to a nely direction and become gusty around 06z behind the
outflow boundary. Should have scattered diurnal cumulus clouds
late Wednesday morning and afternoon as the atmosphere becomes
very unstable along the weakening cold front which will sag
southward through central MO. Will likely be isolated to scattered
thunderstorms Wednesday afternoon, but may leave out of the STL
taf for now. The surface wind will become nely Wednesday
afternoon as the front sags south of STL.
GKS
&&
.PRELIMINARY POINT TEMPS/POPS:
Saint Louis 94 77 92 77 / 40 20 40 20
Quincy 87 71 88 71 / 20 20 40 20
Columbia 92 72 92 72 / 20 20 20 10
Jefferson City 93 72 92 72 / 30 20 10 10
Salem 93 71 89 71 / 30 20 30 20
Farmington 95 71 91 71 / 40 20 20 10
&&
.LSX WATCHES/WARNINGS/ADVISORIES:
MO...HEAT ADVISORY until 8 PM CDT this evening FOR Audrain MO-Boone
MO-Callaway MO-Cole MO-Crawford MO-Franklin MO-Gasconade MO-
Iron MO-Madison MO-Moniteau MO-Montgomery MO-Osage MO-
Reynolds MO-St. Francois MO-Ste. Genevieve MO-Warren MO-
Washington MO.
EXCESSIVE HEAT WARNING until 8 PM CDT this evening FOR Jefferson
MO-Lincoln MO-St. Charles MO-St. Louis City MO-St. Louis MO.
IL...EXCESSIVE HEAT WARNING until 8 PM CDT this evening FOR Bond IL-
Calhoun IL-Clinton IL-Fayette IL-Greene IL-Jersey IL-
Macoupin IL-Madison IL-Marion IL-Monroe IL-Montgomery IL-
Randolph IL-St. Clair IL-Washington IL.
&&
$$
WFO LSX
AREA FORECAST DISCUSSION...UPDATED AVIATION
NWS ST LOUIS MO
1120 PM CDT Tue Aug 26 2014
.SHORT TERM: (Through Late Tonight)
Issued at 324 PM CDT Tue Aug 26 2014
A fairly well-defined convergence zone extends along an axis from
Champaign through St. Louis towards Springfield this afternoon
associated with an old convective boundary. SBCAPE is over 4000
j/kg with little CIN along this corridor, and scattered storms
were noted along portions of the boundary. Short range HRRR and
RAP guidance suggests some of this activity may linger past sunset
and thus have included some low pops within the region. Otherwise the
other threat of showers and thunderstorms tonight will shift
northward along and north of the real east-west frontal boundary
which will be drapped across northern KS and northern MO into
central IL, mainly late tonight.
Glass
.LONG TERM: (Wednesday through Next Tuesday)
Issued at 324 PM CDT Tue Aug 26 2014
The east-west frontal boundary will gradually sink southward
throughout the day Wednesday settling into southern MO and
southern IL by early evening. Very unstable conditions due to
daytime heating and high dew points will persist and maintain a
threat of scattered showers and thunderstorms will the front, and
just to its north. Present indications are that overall the
atmosphere will be slightly cooler in the low-mid levels. This
cooling along with the front and attendant clouds/precipitation
are expected to diminish the magnitude of the recent heat. However
despite slightly cooler temperatures, the pooling of surface dew
points in the 70s will continue to produce afternoon heat index
values of 100-105 degrees along and south of a Columbia to
Litchfield line. I have extended the heat advisories and warnings
in this region, while the excessive heat appears to be over across
northern MO and central IL where cooler conditions have also been
noted today.
The east-west front is expected to retreat back northward on
Thursday as an upper trof migrates out of the Rockies and the
associated surface low lifts northeastward. The highest pops will
remain along and north of the retreating boundary, primarily
northern sections of the CWA Thursday-Thursday night. Heat is a tough
call on Thursday and the current forecast calls for highs in the
upper 80s to lower 90s. There could potentially be some lingering
pockets of afternoon HI values of 100+ but there is too much
uncertainty to extend any heat headlines to this time period.
The heat should definitely come to an end by the weekend. The models
move the upper trof from the Plains on Friday into and through the
MS Valley by late Sunday. A good chance of showers and thunderstorms
will accompany this trof and the attendant frontal system, with
cooler temperatures closer to normal for this time of year.
Glass
&&
.AVIATION: (For the 06z TAFs through 06z Wednesday Night)
Issued at 1054 PM CDT Tue Aug 26 2014
Cluster of storms northeast of the St Louis metro area will
likely slowly dissipate late tonight, although could not rule out
an isolated storm along the outflow boundary moving southwestward
through the St Louis metro. The surface wind will temporarily
switch to a northeast direction and pick up behind the outflow
boundary. A cold front was across northern MO, just south of UIN
this evening. This front will sag slowly southward late tonight
and Wednesday with scattered convection possible along and just
north of this front. Latest HRRR model run keeps UIN dry late
tonight, but there may be at least isolated showers/storms in the
UIN area late tonight into Wednesday morning. Due to uncertainty
in timing and coverage may keep the UIN taf dry for now. With
mostly light surface winds, mainly just high level clouds, and
high surface dew points there will likely be some fog late
tonight/early Wednesday morning mainly in SUS and CPS. The surface
wind will be mainly nely in UIN and COU Wednesday, and becoming
nely Wednesday afternoon in the St Louis metro area after fropa.
Specifics for KSTL: May need to include VCTS in the STL taf around
06-07z late tonight if storms develop along outflow boundary
dropping southwestward through STL. The wind will also briefly
switch to a nely direction and become gusty around 06z behind the
outflow boundary. Should have scattered diurnal cumulus clouds
late Wednesday morning and afternoon as the atmosphere becomes
very unstable along the weakening cold front which will sag
southward through central MO. Will likely be isolated to scattered
thunderstorms Wednesday afternoon, but may leave out of the STL
taf for now. The surface wind will become nely Wednesday
afternoon as the front sags south of STL.
GKS
&&
.LSX WATCHES/WARNINGS/ADVISORIES:
MO...HEAT ADVISORY until 8 PM CDT Wednesday FOR Audrain MO-Boone MO-
Callaway MO-Cole MO-Crawford MO-Franklin MO-Gasconade MO-
Iron MO-Madison MO-Moniteau MO-Montgomery MO-Osage MO-
Reynolds MO-St. Francois MO-Ste. Genevieve MO-Warren MO-
Washington MO.
EXCESSIVE HEAT WARNING until 8 PM CDT Wednesday FOR Jefferson MO-
Lincoln MO-St. Charles MO-St. Louis City MO-St. Louis MO.
IL...EXCESSIVE HEAT WARNING until 8 PM CDT Wednesday FOR Bond IL-
Calhoun IL-Clinton IL-Fayette IL-Greene IL-Jersey IL-
Macoupin IL-Madison IL-Marion IL-Monroe IL-Montgomery IL-
Randolph IL-St. Clair IL-Washington IL.
&&
$$
WFO LSX
AREA FORECAST DISCUSSION
NWS BISMARCK ND
431 AM CDT WED AUG 27 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 431 AM CDT WED AUG 27 2014
FOR THE NEAR TERM/EARLY THIS MORNING...THE CURRENT FOG/STRATUS
IMAGERY LOOP IN COMBINATION WITH SURFACE OBSERVATIONS SHOWS DENSE
FOG EXPANDING OVER MOST OF CENTRAL NORTH DAKOTA. BASED ON CURRENT
VISIBILITY TRENDS AND LATEST HRRR VISIBILITY FORECAST...HAVE
ISSUED A DENSE FOG ADVISORY FOR MOST OF CENTRAL NORTH DAKOTA
THROUGH LATE WEDNESDAY MORNING.
OTHERWISE...A CLEAR SKY DOMINATES WEST AND NORTH WITH THE LATEST
WATER VAPOR IMAGERY SHOWING SUBSIDENCE BEHIND A NORTHERN STREAM
SHORTWAVE NOW INTO MINNESOTA. SPLIT FLOW CONTINUES WITH THE
SOUTHERN BRANCH EXTENDING FROM THE GREAT BASIN INTO SOUTH DAKOTA.
AN UPPER LOW/TROUGH WAS SEEN OVER WESTERN NEVADA EARLY THIS MORNING.
EXPECTING PLENTY OF SUNSHINE TODAY WITH TEMPERATURES WARMING INTO
THE 70S...AND LOWER 80S IN THE FAR WEST. ALL MODEL GUIDANCE...WITH
THE EXCEPTION OF THE GFS...ARE IN AGREEMENT THAT THE SOUTHERN
BRANCH MAKES A RETURN INTO SOUTHERN NORTH DAKOTA WEDNESDAY NIGHT.
AS THE AFOREMENTIONED GREAT BASIN LOW/TROUGH SHIFTS EAST...A
SURFACE LOW WILL TAKE SHAPE OVER NEBRASKA AND SOUTH DAKOTA LATER
TODAY INTO TONIGHT. LATEST TRENDS INDICATE THE NORTHERN FRINGE OF
PRECIPITATION WILL REACH THE JAMES RIVER VALLEY BETWEEN 06Z AND
12Z THURSDAY. AFTER COLLABORATING WITH ABERDEEN AND GRAND
FORKS...HAVE INTRODUCED A SLIGHT CHANCE MENTION FOR SHOWERS AND WILL
LET SUBSEQUENT SHIFTS LOOK AT THE LATEST DATA TO FINE TUNE.
.LONG TERM...(THURSDAY THROUGH TUESDAY)
ISSUED AT 431 AM CDT WED AUG 27 2014
DURING THIS PERIOD THERE WILL BE SEVERAL COLD FRONTAL PASSAGES THAT
WILL BRING SOME ACTIVE WEATHER TO THE REGION OVER THE LABOR DAY
WEEKEND. FIRST...THE REMNANTS OF AN UPPER LEVEL LOW WILL TRACK SOUTH
OF THE STATE THURSDAY. WHILE THIS FEATURE WILL IMPACT THE AREAS
SOUTH OF THE STATE WITH SEVERAL LARGE MCS TYPE CONVECTIVE
SYSTEMS...THERE WILL BE SOME RESIDUAL MOISTURE PULLED INTO THE
STATE...MAINLY ACROSS THE JAMES RIVER VALLEY THURSDAY MORNING. BUT
THERE WILL LIKELY BE MORE CLOUDS THROUGH THE DAY THURSDAY THAN
PREVIOUSLY THOUGHT ACROSS A LARGE PORTION OF SOUTHERN AND EASTERN
NORTH DAKOTA. AFTER THIS A COLD FRONT WILL ENTER THE NORTHWEST
SUPPORTED BY A RATHER WEAK LEADING SHORTWAVE TROUGH AHEAD OF A MORE
SIGNIFICANT SHORTWAVE STILL LINGERING ACROSS THE NORTHWEST US FRIDAY.
OVERALL...HAVE DOWN PLAYED THE POPS THURSDAY NIGHT AND
FRIDAY...WAITING INSTEAD FOR THE MORE SIGNIFICANT SHORTWAVE DUE IN
SATURDAY NIGHT AND SUNDAY. WITH THIS NEXT SYSTEM WILL SEE MORE
SIGNIFICANT PRECIPITATION WITH STRONGER WARM/COLD FRONTAL PASSAGES.
SO THE HOLIDAY WEEKEND SHOULD BE A BIT SOGGY SATURDAY NIGHT WITH
SCATTERED SHOWERS ON SUNDAY. COOL CYCLONIC FLOW ALOFT SHOULD
MAINTAIN SLIGHT THREAT FOR THUNDERSTORMS MONDAY AND TUESDAY.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z THURSDAY MORNING)
ISSUED AT 431 AM CDT WED AUG 27 2014
WIDESPREAD DENSE FOG FROM KBIS TO KJMS WILL POSE AS THE HIGHEST
IMPACT TO AVIATION THROUGH 16Z WEDNESDAY. EXPECT VLIFR CIGS/VSBYS
THROUGH 16Z WEDNESDAY. OTHERWISE SKC FOR THE REMAINING TERMINALS
WITH LIGHT WINDS THROUGH 00Z THURSDAY. MOISTURE IS FORECAST TO
RETURN TO KBIS/KJMS WEDNESDAY NIGHT RESULTING IN A SLIGHT CHANCE
FOR SHOWERS AT KJMS. MVFR CIGS POSSIBLE AT BOTH KBIS AND KJMS
AFTER 01Z THURSDAY.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
DENSE FOG ADVISORY UNTIL 11 AM CDT /10 AM MDT/ THIS MORNING FOR
NDZ019>023-025-034>037-041-042-044>048-050-051.
&&
$$
SHORT TERM...KS
LONG TERM...WAA
AVIATION...KS
AREA FORECAST DISCUSSION
NWS BISMARCK ND
421 AM CDT WED AUG 27 2014
.UPDATE...
ISSUED AT 421 AM CDT WED AUG 27 2014
DENSE FOG CONTINUES TO FORM OVER MOST OF CENTRAL NORTH DAKOTA.
WITH VISIBILITIES AT OR LESS THAN ONE QUARTER OF A MILE IN
SEVERAL LOCATIONS. A DENSE FOG ADVISORY HAS BEEN ISSUED. UPDATES
TO PRODUCTS FORTHCOMING.
UPDATE ISSUED AT 1157 PM CDT TUE AUG 26 2014
LATEST FOG/STRATUS LOOP SHOWS MOSTLY CLOUDY TO CLOUDY CONDITIONS
FROM BISMARCK/MANDAN...EAST AND SOUTH. A CLEAR SKY WAS OBSERVED
ELSEWHERE. LATEST HRRR CIG/VSBY FORECAST SHOWS CLOUDS ERODING
WHICH IS ON TRACK PER SATELLITE LOOP OVER THE LAST HOUR. HOWEVER
THIS AREA OF CLEARING IS REPLACED BY FOG OVERNIGHT WHERE WE HAD
THE LIGHT RAIN EARLIER TUESDAY. CONCUR WITH THIS IDEA...BUT
UNCERTAINTY ON HOW WIDESPREAD AND DENSE FOG WILL BECOME IS THE
MAIN ISSUE FOR THE REST OF THE OVERNIGHT PERIOD. WILL CONTINUE
WITH THE CURRENT PATCHY FOG WORDING AND MONITOR OVERNIGHT. REST OF
FORECAST ELEMENTS ARE ON TRACK.
UPDATE ISSUED AT 1000 PM CDT TUE AUG 26 2014
CONTINUED TREND TO DECREASE RAIN SOUTHEAST...LAMOURE AND DICKEY
COUNTIES...OVER THE NEXT TWO HOURS...AND DECREASE CLOUDS THROUGH
THE NIGHT.
PATCHY FOG CONTINUES IN THE FORECAST FOR THE DAYBREAK TIME FRAME.
JP MARTIN
UPDATE ISSUED AT 735 PM CDT TUE AUG 26 2014
HAVE TIMED THE SHOWERS OUT OF THE SOUTHEAST ART OF THE FORECAST
AREA FOR BETWEEN 10 AND 11 PM CDT THIS EVENING. THEN DECREASED
CLOUDS NORTHWEST TO SOUTHEAST. HAVE INTRODUCED PATCHY FOG ACROSS
THE SOUTH...FROM BOWMAN AND BISMARCK TO ELLENDALE AND JAMESTOWN
FOR AROUND DAYBREAK. DEW POINTS ARE FORECAST TO DROP INTO THE
UPPER 40S WITH ACTUAL TEMPERATURES IN THE SAME BALLPARK. THIS IS
ALSO THE AREA THAT RECEIVED LIGHT RAIN THIS AFTERNOON / EVENING.
&&
.SHORT TERM...(THIS EVENING THROUGH WEDNESDAY)
ISSUED AT 310 PM CDT TUE AUG 26 2014
LATEST SATELLITE IMAGERY SHOWS A NICE SHORTWAVE TROUGH CURRENTLY
DROPPING SOUTHEAST ACROSS SOUTHERN SASKATCHEWAN...IN ADDITION TO
AN AREA OF STRONG UPPER LEVEL FLOW ACROSS THE CENTRAL/NORTHERN
ROCKIES INTO THE DAKOTAS. THIS HAS PRODUCED SUFFICIENT
FORCING...COMBINED WITH WEAK ISENTROPIC LIFT TO PRODUCE A NARROW
BAND OF SHOWERS ACROSS SOUTHWEST INTO SOUTH CENTRAL NORTH
DAKOTA. THE PAST FEW RUNS OF THE RAP/HRRR HAVE COME INTO BETTER
AGREEMENT IN SPREADING THIS BAND ACROSS CENTRAL AND INTO EASTERN
NORTH DAKOTA...ALONG AND SOUTH OF INTERSTATE 94. AREAS AFFECTED
WILL REMAIN CONFINED TO AN PRETTY NARROW BAND WITH RAINFALL
AMOUNTS OF ONLY A COUPLE HUNDREDTHS.
EXPECT THESE SHOWERS TO EXIT THE JAMES RIVER VALLEY LATER THIS
EVENING WITH CLEAR TO PARTLY CLOUDY SKIES THEREAFTER. STILL A COOL
NIGHT IN STORE...BUT WITH LOW-MID LEVEL TEMPERATURES EXPECTED TO
CONTINUE TO WARM...LOWS TONIGHT SHOULD BE MAINLY IN THE 40S TO
LOWER 50S.
WEAK UPPER LEVEL RIDGING ON WEDNESDAY WILL HELP BUMP OUR DAYTIME
TEMPERATURES INTO THE 70S...WITH A FEW LOWER 80S POSSIBLE FAR
WEST.
.LONG TERM...(WEDNESDAY NIGHT THROUGH TUESDAY)
ISSUED AT 310 PM CDT TUE AUG 26 2014
QUIET/ZONAL FLOW AT THE ONSET OF THE LONG TERM PERIOD WILL
TRANSITION TO MORE ACTIVE LATE THURSDAY NIGHT THROUGH THE WEEKEND
AS AN UPPER TROUGH MOVES INLAND AND ACROSS THE CENTRAL CONUS.
DRY CONDITIONS PREVAIL WEDNESDAY NIGHT THROUGH THURSDAY EVENING
WITH THE MAIN STORM TRACKS NORTH AND SOUTH OF NORTH DAKOTA.
EMBEDDED LEAD S/WV IMPULSE EJECTING OUT OF AN ALASKAN LONG WAVE
TROUGH IS THEN DEPICTED TO APPROACH AND MOVE ACROSS THE NORTHERN
PLAINS LATE THURSDAY NIGHT THROUGH FRIDAY AFTERNOON BRINGING AN
ISOLATED THREAT FOR THUNDERSTORMS TO THE REGION.
BETTER AND MORE WIDESPREAD PRECIPITATION CHANCES ARRIVE SATURDAY
NIGHT INTO EARLY NEXT WEEK WHEN OUR FLOW ALOFT BECOMES
SOUTHWESTERLY AS THE AFOREMENTIONED LONG WAVE TROUGH DEVELOPS
SOUTHWEST INTO THE PACIFIC NORTHWEST...THEN MOVES EAST ACROSS THE
ROCKIES AND THROUGH THE GREAT PLAINS.
TEMPERATURES WILL REMAIN NEAR TO SLIGHTLY BELOW NORMAL...WITH
HIGHS IN THE 70S TO LOWER 80S AND LOWS IN THE UPPER 40S AND 50S.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z WEDNESDAY NIGHT)
ISSUED AT 1157 PM CDT TUE AUG 26 2014
LIGHT RAIN FROM TUESDAY...ALONG WITH DECREASING CLOUDS AND LIGHT
WINDS AT KBIS TO KJMS WILL PROMOTE FOG DEVELOPMENT THROUGH 15Z
WEDNESDAY. WILL MAINTAIN MVFR VSBYS FOR THE 06Z TAF ISSUANCE AND
MONITOR OVERNIGHT FOR POSSIBLE ADJUSTMENTS DOWNWARD. OTHERWISE...SKC
FOR THE REMAINING TERMINALS WITH LIGHT WINDS THROUGH 00Z THURSDAY.
INDICATION BEYOND 00Z THURSDAY IS POTENTIAL FOR MVFR CIGS APPEARING
AT KBIS AND KJMS AS MOISTURE IS FORECAST TO MOVE NORTH FROM SOUTH
DAKOTA WEDNESDAY NIGHT.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
DENSE FOG ADVISORY UNTIL 11 AM CDT /10 AM MDT/ THIS MORNING FOR
NDZ019>023-025-034>037-041-042-044>048-050-051.
&&
$$
UPDATE...KS
SHORT TERM...TWH
LONG TERM...NH
AVIATION...KS
AREA FORECAST DISCUSSION
NWS BISMARCK ND
1157 PM CDT TUE AUG 26 2014
.UPDATE...
ISSUED AT 1157 PM CDT TUE AUG 26 2014
LATEST FOG/STRATUS LOOP SHOWS MOSTLY CLOUDY TO CLOUDY CONDITIONS
FROM BISMARCK/MANDAN...EAST AND SOUTH. A CLEAR SKY WAS OBSERVED
ELSEWHERE. LATEST HRRR CIG/VSBY FORECAST SHOWS CLOUDS ERODING
WHICH IS ON TRACK PER SATELLITE LOOP OVER THE LAST HOUR. HOWEVER
THIS AREA OF CLEARING IS REPLACED BY FOG OVERNIGHT WHERE WE HAD
THE LIGHT RAIN EARLIER TUESDAY. CONCUR WITH THIS IDEA...BUT
UNCERTAINTY ON HOW WIDESPREAD AND DENSE FOG WILL BECOME IS THE
MAIN ISSUE FOR THE REST OF THE OVERNIGHT PERIOD. WILL CONTINUE
WITH THE CURRENT PATCHY FOG WORDING AND MONITOR OVERNIGHT. REST OF
FORECAST ELEMENTS ARE ON TRACK.
UPDATE ISSUED AT 1000 PM CDT TUE AUG 26 2014
CONTINUED TREND TO DECREASE RAIN SOUTHEAST...LAMOURE AND DICKEY
COUNTIES...OVER THE NEXT TWO HOURS...AND DECREASE CLOUDS THROUGH
THE NIGHT.
PATCHY FOG CONTINUES IN THE FORECAST FOR THE DAYBREAK TIME FRAME.
JP MARTIN
UPDATE ISSUED AT 735 PM CDT TUE AUG 26 2014
HAVE TIMED THE SHOWERS OUT OF THE SOUTHEAST ART OF THE FORECAST
AREA FOR BETWEEN 10 AND 11 PM CDT THIS EVENING. THEN DECREASED
CLOUDS NORTHWEST TO SOUTHEAST. HAVE INTRODUCED PATCHY FOG ACROSS
THE SOUTH...FROM BOWMAN AND BISMARCK TO ELLENDALE AND JAMESTOWN
FOR AROUND DAYBREAK. DEW POINTS ARE FORECAST TO DROP INTO THE
UPPER 40S WITH ACTUAL TEMPERATURES IN THE SAME BALLPARK. THIS IS
ALSO THE AREA THAT RECEIVED LIGHT RAIN THIS AFTERNOON / EVENING.
&&
.SHORT TERM...(THIS EVENING THROUGH WEDNESDAY)
ISSUED AT 310 PM CDT TUE AUG 26 2014
LATEST SATELLITE IMAGERY SHOWS A NICE SHORTWAVE TROUGH CURRENTLY
DROPPING SOUTHEAST ACROSS SOUTHERN SASKATCHEWAN...IN ADDITION TO
AN AREA OF STRONG UPPER LEVEL FLOW ACROSS THE CENTRAL/NORTHERN
ROCKIES INTO THE DAKOTAS. THIS HAS PRODUCED SUFFICIENT
FORCING...COMBINED WITH WEAK ISENTROPIC LIFT TO PRODUCE A NARROW
BAND OF SHOWERS ACROSS SOUTHWEST INTO SOUTH CENTRAL NORTH
DAKOTA. THE PAST FEW RUNS OF THE RAP/HRRR HAVE COME INTO BETTER
AGREEMENT IN SPREADING THIS BAND ACROSS CENTRAL AND INTO EASTERN
NORTH DAKOTA...ALONG AND SOUTH OF INTERSTATE 94. AREAS AFFECTED
WILL REMAIN CONFINED TO AN PRETTY NARROW BAND WITH RAINFALL
AMOUNTS OF ONLY A COUPLE HUNDREDTHS.
EXPECT THESE SHOWERS TO EXIT THE JAMES RIVER VALLEY LATER THIS
EVENING WITH CLEAR TO PARTLY CLOUDY SKIES THEREAFTER. STILL A COOL
NIGHT IN STORE...BUT WITH LOW-MID LEVEL TEMPERATURES EXPECTED TO
CONTINUE TO WARM...LOWS TONIGHT SHOULD BE MAINLY IN THE 40S TO
LOWER 50S.
WEAK UPPER LEVEL RIDGING ON WEDNESDAY WILL HELP BUMP OUR DAYTIME
TEMPERATURES INTO THE 70S...WITH A FEW LOWER 80S POSSIBLE FAR
WEST.
.LONG TERM...(WEDNESDAY NIGHT THROUGH TUESDAY)
ISSUED AT 310 PM CDT TUE AUG 26 2014
QUIET/ZONAL FLOW AT THE ONSET OF THE LONG TERM PERIOD WILL
TRANSITION TO MORE ACTIVE LATE THURSDAY NIGHT THROUGH THE WEEKEND
AS AN UPPER TROUGH MOVES INLAND AND ACROSS THE CENTRAL CONUS.
DRY CONDITIONS PREVAIL WEDNESDAY NIGHT THROUGH THURSDAY EVENING
WITH THE MAIN STORM TRACKS NORTH AND SOUTH OF NORTH DAKOTA.
EMBEDDED LEAD S/WV IMPULSE EJECTING OUT OF AN ALASKAN LONG WAVE
TROUGH IS THEN DEPICTED TO APPROACH AND MOVE ACROSS THE NORTHERN
PLAINS LATE THURSDAY NIGHT THROUGH FRIDAY AFTERNOON BRINGING AN
ISOLATED THREAT FOR THUNDERSTORMS TO THE REGION.
BETTER AND MORE WIDESPREAD PRECIPITATION CHANCES ARRIVE SATURDAY
NIGHT INTO EARLY NEXT WEEK WHEN OUR FLOW ALOFT BECOMES
SOUTHWESTERLY AS THE AFOREMENTIONED LONG WAVE TROUGH DEVELOPS
SOUTHWEST INTO THE PACIFIC NORTHWEST...THEN MOVES EAST ACROSS THE
ROCKIES AND THROUGH THE GREAT PLAINS.
TEMPERATURES WILL REMAIN NEAR TO SLIGHTLY BELOW NORMAL...WITH
HIGHS IN THE 70S TO LOWER 80S AND LOWS IN THE UPPER 40S AND 50S.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z WEDNESDAY NIGHT)
ISSUED AT 1157 PM CDT TUE AUG 26 2014
LIGHT RAIN FROM TUESDAY...ALONG WITH DECREASING CLOUDS AND LIGHT
WINDS AT KBIS TO KJMS WILL PROMOTE FOG DEVELOPMENT THROUGH 15Z
WEDNESDAY. WILL MAINTAIN MVFR VSBYS FOR THE 06Z TAF ISSUANCE AND
MONITOR OVERNIGHT FOR POSSIBLE ADJUSTMENTS DOWNWARD. OTHERWISE...SKC
FOR THE REMAINING TERMINALS WITH LIGHT WINDS THROUGH 00Z THURSDAY.
INDICATION BEYOND 00Z THURSDAY IS POTENTIAL FOR MVFR CIGS APPEARING
AT KBIS AND KJMS AS MOISTURE IS FORECAST TO MOVE NORTH FROM SOUTH
DAKOTA WEDNESDAY NIGHT.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...KS
SHORT TERM...TWH
LONG TERM...NH
AVIATION...KS
AREA FORECAST DISCUSSION FOR WESTERN SD AND NORTHEASTERN WY
NWS RAPID CITY SD
254 AM MDT WED AUG 27 2014
.SHORT TERM...TODAY THROUGH THURSDAY NIGHT
ISSUED AT 251 AM MDT WED AUG 27 2014
LATEST WATER VAPOR IMAGERY SHOWS AN AREA OF LOW PRESSURE OVER
NEVADA/UTAH WITH A NORTHERN STREAM TROUGH EXTENDING FROM CENTRAL
CANADA INTO THE NORTHERN PLAINS. THE NORTHERN STREAM TROF WILL
QUICKLY MOVE EASTWARD AS THE CUTOFF LOW SLOWLY PROPAGATES INTO THE
CENTRAL ROCKIES. SOUTHWESTERLY FLOW CONTINUES OVER THE
CENTRAL/NORTHERN PLAINS.
FOR TODAY THE BEST FORCING REMAINS SOUTH OF THE CWA. BEST CHANCES
OF PRECIP THROUGH THURSDAY WILL BE ACROSS THE FAR SOUTHERN PORTIONS
OF THE FORECAST AREA AS A SERIES OF WAVES CROSS THE COLORADO/NEBRASKA
AREA. MODELS ARE VARYING WITH TIMING OF WAVES AND HOW FAR NORTH
THE PRECIP WILL EXTEND WITHIN THE CWA. EITHER WAY QPF AMOUNTS WILL
BE LIMITED...EXCEPT WITH THE POSSIBILITY OF SOME STRONGER STORMS
CROSSING AREAS NEAR THE NEBRASKA BORDER. HIGH TEMPERATURES TODAY
WILL ONCE AGAIN BE BELOW AVERAGE DUE TO CLOUD COVER. AS THE UPPER
LOW MOVES THROUGH NEBRASKA/KANSAS...PRECIP CHANCES WILL DIMINISH
ACROSS THE AREA WITH DRY CONDITIONS BY THURSDAY AFTERNOON/EVENING.
&&
.LONG TERM...FRIDAY THROUGH TUESDAY
ISSUED AT 251 AM MDT WED AUG 27 2014
PROGRESSIVE NORTHERN STREAM FLOW WILL CONTINUE THROUGH THE
PERIOD. TWO MAIN SYSTEMS EXPECTED TO AFFECT THE REGION IN THE
PERIOD...A WEAK NORTHERN STREAM TROUGH FRIDAY...AND A MORE ROBUST
LONGWAVE UPPER TROUGH SAT NIGHT INTO MONDAY. FORECAST MODELS IN
GOOD AGREEMENT PER WAVE AMPLITUDE AND TRACK. HOWEVER...SOME
SUBSTANTIAL DIFFERENCES BEGIN TO EMERGE IN THE SUNDAY NIGHT INTO
MONDAY PERIOD BETWEEN THE ECMWF AND GFS...MAINLY THE HANDLING OF
THE NW CONUS SOUTHERN PERIPHERY EJECTING IMPULSE. THE ECMWF HAS A
SOUTHERN BIAS TO THE SYSTEM WITH THE BULK OF LSA PASSING THROUGH
THE FA AS OPPOSED TO A MORE NORTHERN TRACK IN THE GFS...WHICH IS
ALSO FASTER. THE ECMWF SOLUTION WOULD SUPPORT BETTER CHANCES FOR
RAIN IN THE FA HOWEVER MOISTURE LIMITATIONS MAY PRECLUDE ANY
PRECIP TOTALS THEN.
RETAINED PREV POPS FOR FRIDAY AFTERNOON...WITH A SLIGHT UPTICK AND
EXPANSION OF SLIGHT MENTION. FORECAST MODELS CONTINUE TO INDICATE A
SFC TROUGH STALLING ACROSS THE SW HALF FRIDAY...WITH A PASSING UPPER
LEVEL IMPULSE. SUFFICIENT LL MOISTURE ND RESULTING CAPE WOULD BE
CONDUCIVE FOR CONVECTION IN THE AFTERNOON...ESP OVER THE BLACK
HILLS. OTHERWISE...A MORE IMPRESSIVE UPPER LEVEL TROUGH WILL PUSH
OUT OF THE NE PAC AND INTO THE NORTHERN PLAINS...SUPPORTING
INCREASING LSA SAT NIGHT THROUGH SUNDAY NIGHT. BETTER SFC CYCLONE
DEVELOPMENT LOOKS TO REMAIN WELL EAST OF THE REGION...SUPPORTING
MORE ELEVATED/CONVECTIVE CHANCES BEHIND THE SFC TROUGH RATHER THAN
WIDESPREAD DEFORMATION RAINS. HENCE...KEPT POPS IN THE SLIGHT TO
LOW CHANCE CAT FOR NOW...ESP AS DEEPER MOISTURE WILL SHIFT QUICKLY
EAST OUT OF THE REGION. KEPT MOST OF THE REGION DRY MONDAY THROUGH
TUES...WITH UPPER LEVEL RIDGING COMMENCING AND DRY PROFILES.
SEASONAL TEMPS EXPECTED IN MOST OF THE PERIOD...WITH BELOW NORMAL
TEMPS /5-10 DEGREES/ EXPECTED MONDAY AND PERHAPS TUES BEHIND
SUNDAY/S COLD FRONT...ESP NW AREAS.
&&
.AVIATION...FOR THE 12Z TAFS THROUGH 12Z WEDNESDAY NIGHT
ISSUED AT 251 AM MDT WED AUG 27 2014
SCT-ISOLD SHOWERS/THUNDERSTORMS EXPECTED ACROSS THE SOUTHERN HALF
THROUGH MOST OF THE PERIOD AS A SERIES OF IMPULSES CROSS THE
REGION. LCL MVFR/IFR CONDS EXP WITH HEAVIER PRECIPITATION.
ADDITIONALLY...IFR CIGS WILL SPREAD NORTH ACROSS SW AND SCENTRAL
SD THIS MORNING...WITH CIGS TRENDING TO MVFR LATE MORNING/EARLY
AFTERNOON. CIGS MAY LINGER THROUGH THE PERIOD THERE. WINDS WILL
VEER SE AROUND KRAP THIS AFTERNOON...WITH THE POTENTIAL FOR MVFR
CIGS TO SPREAD INTO THE RAP TERMINAL THEN. HAVE HINTED AT THIS IN
THE TAF.
&&
.UNR WATCHES/WARNINGS/ADVISORIES...
SD...NONE.
WY...NONE.
&&
$$
SHORT TERM...MLS
LONG TERM...JC
AVIATION...JC
AREA FORECAST DISCUSSION
NWS NASHVILLE TN
345 AM CDT WED AUG 27 2014
.DISCUSSION...
UPPER RIDGING IN CONTROL ACROSS THE SOUTHEASTERN U.S.. AT THE
SFC...HIGH PRESSURE IS LOCATED OVER THE GREAT LAKES REGION. THIS
FEATURE IS LARGE ENOUGH TO CONTROL OUR WEATHER AND A LIGHT NE FLOW
IS EXPECTED TODAY. ON THURSDAY...THE UPPER HIGH WILL BUILD SE TOWARD
NRN FL WITH A RIDGE AXIS EXTENDING NW ACROSS TN. ALL OF THIS RIDGING
WILL ACT TO IMPEDE ANY LOW LEVEL BOUNDARY INFLUENCE. CONVECTIVE
PARAMETERS SHOW VERY LITTLE CHANCE OF CONVECTION FOR TODAY. BUT...WE
DO SEE AN INCREASE IN CAPE VALUES ON THU AFTERNOON...BUT THIS IS
ACROSS THE NORTH ONLY. SO...WILL INCLUDE A SLIGHT CHANCE OF AFT
SHOWERS AND TSTMS. FURTHERMORE...THE HRRR IS SHOWING SOME AFT
DEVELOPMENT ACROSS THE KY AREA THIS AFTERNOON. MID/UPPER LEVEL
FLOW PATTERN DICTATES THAT THIS ACTIVITY WILL MOVE SE.
THEREFORE...MAY NEED TO INCLUDE A SLIGHT CHANCE OF AFT SHOWERS AND
TSTMS ACROSS THE NORTH FOR TODAY AS WELL. WILL LEAN TOWARD ISC AND
CURRENT GRIDS FOR A FINAL DECISION.
FOR THE NEAR TERM TEMPS...ABOVE NORMAL TEMPS EXPECTED WITH HIGHS
GENERALLY IN THE LOWER 90S...LOWS LOWER 70S...COOLER PLATEAU.
IN THE EXT FCST...SHORTWAVE TO DEVELOP OVER THE NATIONS INTERIOR
THIS WEEKEND. WIND FLOW PATTERN WILL THEN EVOLVE INTO A MORE UNIFORM
SOUTHERLY FLOW WHICH WILL BRING INCREASING MOISTURE LEVELS BACK
ACROSS THE AREA. THOUGH THE SHORTWAVE WILL LIFT OFF TO THE NE AND
NOT DIRECTLY IMPACT THE MID STATE...CONVECTIVE CONDITIONS WILL
BECOME MORE FAVORABLE. THE GFS ACTUALLY EMPHASIZES AN UPSTREAM
IMPULSE IN CLOSE PROXIMITY FOR SAT NT. SO...ALL IN ALL... POPS
WILL BE ON THE INCREASE FOR THE SAT THROUGH MON PERIOD.
THEREAFTER...W-E UPPER RIDGING WILL REDEVELOP ACROSS THE DEEP
SOUTH WITH POPS ON THE DOWNSWING.
FOR THE EXT TEMPS...ABOVE NORMAL VALUES TO CONTINUE EVEN THOUGH
RIDGING BACKS OFF DURING THE SAT THROUGH MON PERIOD. HEIGHTS
REMAIN ON THE ELEVATED SIDE.
&&
.PRELIMINARY POINT TEMPS/POPS...
NASHVILLE 92 72 94 72 / 05 05 20 05
CLARKSVILLE 93 69 94 69 / 10 05 20 10
CROSSVILLE 86 65 89 67 / 05 0 20 05
COLUMBIA 92 70 94 70 / 0 05 10 05
LAWRENCEBURG 92 66 94 67 / 0 05 10 05
WAVERLY 93 69 94 69 / 10 05 10 10
&&
.OHX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
21
AREA FORECAST DISCUSSION...UPDATED
NWS CORPUS CHRISTI TX
1237 AM CDT WED AUG 27 2014
.DISCUSSION...UPDATED FOR 06Z AVIATION.
&&
.AVIATION...MOISTURE WILL CONTINUE TO INCREASE ACROSS THE GULF
WATERS AND COASTAL LOCATIONS. APPROACHING UPPER DISTURBANCE WILL
RESULT IN SHOWERS AND THUNDERSTORMS MAINLY ACROSS THE COASTAL BEND
AND HAVE INCLUDED VCSH/VCTS REMARKS AT CRP/VCT. WILL PREVAIL OR
TEMPO SHRA/TSRA IN LATER FORECASTS IF CONFIDENCE INCREASES.
GENERALLY VFR CONDITIONS WILL PREVAIL THROUGH THE PERIOD... BUT
LOWER CIGS/VSBYS WILL BE POSSIBLE IF SHOWERS/STORMS DIRECTLY
IMPACT A TAF SITE.
&&
.PREV DISCUSSION... /ISSUED 943 PM CDT TUE AUG 26 2014/
DISCUSSION...SATELLITE IMAGERY SHOWS THE MID LEVEL LOW OVER THE
NORTHERN GULF OF MEXICO SOUTH OF LAKE CHARLES. THE SURFACE TROUGH
AXIS EXTENDS ACROSS THE GULF OF MEXICO FROM THE YUCATAN CHANNEL
NORTHWEST TO THE UPPER TEXAS COAST. 00Z CRP SOUNDING INDICATED AN
INCREASE IN MOISTURE OVER THE REGION UP TO 2 INCHES...WHILE GOES
SOUNDER SHOWS HIGHER MOISTURE OVER THE NORTHWEST GULF OF MEXICO
NEAR THE MID LEVEL LOW. THIS MOISTURE WILL BE MOVING INTO THE
COASTAL WATERS OVERNIGHT. LATEST RUNS OF NAM/GFS SHOWED AN INCREASE
IN LOW LEVEL CONVERGENCE OVER THE COASTAL WATERS LATE TONIGHT INTO
WEDNESDAY MORNING. HI RES MODELS FROM TEXAS TECH WRF AND HRRR SHOWED
AREAS OF CONVECTION INCREASING OVER THE COASTAL WATERS LATER TONIGHT
INTO WEDNESDAY. RAISED POPS TO LIKELY CATEGORY FOR THE OFFSHORE
WATERS LATE TONIGHT THROUGH WEDNESDAY. NORTHEAST WINDS MAY APPROACH
SCEC LEVELS OVER THE GULF WATERS ON WEDNESDAY.
PREV DISCUSSION... /ISSUED 636 PM CDT TUE AUG 26 2014/
DISCUSSION...UPDATED FOR 00Z AVIATION.
AVIATION...SHOWERS MAINLY ENDING THIS EVENING...BUT HAVE A FEW
REMAINING BETWEEN ALI AND COT. THESE WILL NOT AFFECT TAF SITES FOR
THE REST OF TONIGHT. OVERNIGHT SHOULD HAVE MAINLY VFR
CONDITIONS...WILL SEE SOME LOW LEVEL CU DEVELOP...BUT DONT EXPECT
A CIG CONDITION. WITH MORE MOISTURE BUILDING IN AND AN APPROACHING
UPPER DISTURBANCE...WILL CONTINUE SHOWER/STORM CHANCES TOMORROW
FOR CRP/VCT TAF SITES. ALI WOULD HAVE SMALLER CHANCE...TOO SMALL
TO INCLUDE IN TAFS THIS SOON.
PREV DISCUSSION... /ISSUED 352 PM CDT TUE AUG 26 2014/
SHORT TERM (TONIGHT THROUGH WEDNESDAY NIGHT)...EXPECTING ACTIVITY
OVER INLAND AREAS TO END AROUND OR BEFORE SUNSET...WITH ACTIVITY
PICKING UP AGAIN OVER THE EASTERN AREAS/GULF WATERS OVERNIGHT.
HOWEVER...ACTIVITY MAY LINGER A BIT MORE OVER THE NORTHEAST BUT
SHOULD EVENTUALLY DIE OFF BEFORE MIDNIGHT...WITH SHOWERS
DEVELOPING OVER THE GULF WATERS OVERNIGHT. THEN...SHOULD BE SEEING
AN INCREASE IN CONVECTION SPREADING FARTHER INLAND ON
WEDNESDAY...WITH THE BETTER CHANCES MORE TOWARD THE NORTHEAST. AM
GOING TO GO WITH ISOLATED TO SCATTERED CONVECTION AS DO EXPECT
CONVECTION WEDNESDAY OVER MOST INLAND AREAS (OBVIOUSLY THE
SCATTERED CONVECTION CLOSER TO THE COAST AND ISOLATED FARTHER
WEST). WILL LIKELY HAVE A BRIEF LULL IN CONVECTION IN THE
EVENING...THEN START UP AGAIN DURING THE LATE EVENING/OVERNIGHT
HOURS WEDNESDAY NIGHT OVER THE COASTAL AREAS. WITH INCREASE IN
MOISTURE...SHOULD SEE A SLIGHT WARM-UP IN OVERNIGHT LOWS TONIGHT
AND WEDNESDAY NIGHT...BUT COOLER TEMPERATURES WEDNESDAY DUE TO
CLOUDS AND RAIN-COOLED AREAS.
MARINE (TONIGHT THROUGH WEDNESDAY NIGHT)...BELOW SCEC CONDITIONS
EXPECTED THROUGH THE PERIOD. SCATTERED SHOWERS/THUNDERSTORMS
BECOME MORE PREVALENT THROUGH THE PERIOD...AS THE TROUGH
APPROACHES THE AREA BRINGING IN DEEPER TROPICAL MOISTURE. WINDS AND
SEAS HIGHER IN THUNDERSTORMS.
LONG TERM (THURSDAY THROUGH TUESDAY)...WITH RESPECT TO THE GFS
ENSEMBLE MEAN...THE UPPER TROUGH/LOW IS EXPECTED TO MEANDER OVER THE
CWA/MSA THURSDAY THEN DISSIPATE FRIDAY AS A PROGRESSIVE SYSTEM
MOVES ACRS THE SRN PLAINS/NRN AND CNTRL TX. SELECT GFS DETERMINISTIC
SOUNDINGS SUGGEST COPIOUS MSTR/VERY HIGH PWAT VALUES OVER THE
CWA/MSA THURSDAY THROUGH SUNDAY. YET...GFS ENSEMBLE MEAN SUGGEST
THAT AN UPPER RIDGE WILL BUILD OVER THE CWA/MSA BEGINNING SUNDAY/
MONDAY. THUS...EXPECT SCT CONVECTION OVER THE CWA/MSA (OWING TO
COPIOUS MSTR AND TO UPPER/SFC FORCING) WITH LOCALLY HEAVY RAINFALL
(EFFICIENT RAINFALL PRODUCTION) THURSDAY/FRIDAY...A DECREASE IN
COVERAGE SATURDAY/SUNDAY...AND NO PCPN MONDAY/TUESDAY. ANTICIPATE
LOWER MAX TEMPS THURSDAY THROUGH SATURDAY WITH A STEADY INCREASE
AFTERWARD. ANTICIPATE MAX HEAT INDEX VALUES 105-109F MONDAY/TUESDAY.
&&
.PRELIMINARY POINT TEMPS/POPS...
CORPUS CHRISTI 95 78 91 78 91 / 40 30 40 30 40
VICTORIA 95 77 92 76 92 / 50 30 40 30 40
LAREDO 102 80 100 80 99 / 10 10 20 20 20
ALICE 98 76 95 77 94 / 30 20 30 30 30
ROCKPORT 91 80 88 80 88 / 50 40 40 30 40
COTULLA 100 76 100 76 98 / 10 10 20 20 20
KINGSVILLE 97 76 94 77 93 / 40 20 40 30 40
NAVY CORPUS 90 81 87 80 88 / 50 40 40 30 40
&&
.CRP WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
GM...NONE.
&&
$$
TB/78...AVIATION
AREA FORECAST DISCUSSION
NWS CHEYENNE WY
355 AM MDT WED AUG 27 2014
.SHORT TERM...(TODAY THROUGH FRIDAY)
ISSUED AT 355 AM MDT WED AUG 27 2014
CLOSED UPPER LOW WAS ENTERING UT FROM NV PER WATER VAPOR IMAGERY.
SOUTHERLY FLOW ALOFT DRAWING MOISTURE FROM HURRICANE MARIE WEST OF
BAJA CA INTO THE CENTRAL AND SOUTHERN ROCKY MOUNTAIN REGION.
SHORTWAVE LIFTING NORTHWARD ACROSS NORTHWEST CO PRODUCING SCATTERED
SHOWERS AND ISOLATED TSTORMS. OTHER CONVECTION WAS DEVELOPING NORTH
OF A STALLED SURFACE FRONT FROM NORTHEAST CO INTO CENTRAL NE. SKIES
WERE PARTLY TO MOSTLY CLOUDY WITH SOME STRATUS FORMING OVER EAST
CENTRAL WY. WINDS WERE LIGHT AND VARIABLE.
THE 00Z SHORT RANGE MODEL GUIDANCE IS IN GOOD AGREEMENT PROGGING THE
UPPER LOW PRESSURE CENTER EVOLVING INTO A OPEN WAVE AS IT PROGRESSES
SLOWLY EAST INTO WESTERN CO THIS AFTERNOON. THE MAJORITY OF THE
MODELS INCLUDING THE ESRL HRRR DEVELOP AN WEST-EAST BAND OF SHOWERS
AND EMBEDDED TSTORMS ALONG THE I-80 CORRIDOR AFTER 12Z AS THE
SHORTWAVE LIFTS NORTH INTO SOUTHERN WY. ADDITIONAL SHOWERS AND
SCATTERED TSTORMS DEVELOP THIS AFTERNOON WITH UPSLOPE SOUTHEASTERLY
FLOW. LOW/MID LEVEL INSTABILITY AND 0-6KM SHEAR PROFILES ARE NOT
CONDUCIVE FOR SEVERE TSTORM DEVELOPMENT...HOWEVER PRECIP WATER
VALUES EXCEED AN INCH MORE INDICATIVE OF LOCALLY HEAVY RAINFALL.
STORM MOTION WILL BE TO THE NORTH AND NORTHEAST AROUND 25 KT WHICH
SHOULD MITIGATE THE FLOOD THREAT. FOLLOWED THE HPC QPF WHICH PROGS
0.5-1.0 INCH RAINFALL OVER THE CWA. IT WILL BE 5-10 DEGREES COOLER
TODAY COMPARED TO YESTERDAY WITH 700MB TEMPERATURES AROUND 7C.
SHOWER COVERAGE WILL DECREASE FROM NUMEROUS THIS EVENING TO LOW END
SCATTERED LATER TONIGHT.
THURSDAY WILL TREND DRIER AS THE UPPER TROUGH AND BETTER MOISTURE
SHIFT SOUTH AND EAST OF THE CWA. STILL CANNOT RULE OUT ISOLATED TO
SCATTERED CONVECTION ALONG AND SOUTH OF I-80 THOUGH. QPF WILL BE
LIGHTER...GENERALLY LESS THAN A QUARTER INCH. HIGH TEMPERATURES WILL
BE 3-5 DEGREES WARMER...ESPECIALLY EAST CENTRAL WY AND NORTHERN NE
PANHANDLE WITH GREATER INSOLATION.
TRANSITORY SHORTWAVE RIDGE THURSDAY NIGHT SHIFTS EAST FRIDAY AS A
SHORTWAVE TROUGH MOVES EAST ACROSS MT AND NORTHERN WY. THIS SYSTEM
WILL NOT HAVE MUCH AVAILABLE MOISTURE TO WORK WITH...BUT DYNAMICS
ENOUGH TO OVERCOME AND PRODUCE ISOLATED AFTERNOON CONVECTION ALONG
AND NORTH OF A LINE FROM DOUGLAS TO CHADRON...AS WELL AS OVER THE
MOUNTAINS. 700MB TEMPERATURES RISE TO AROUND 10C FRIDAY AFTERNOON
WITH READINGS IN THE 80S EAST OF THE LARAMIE RANGE.
.LONG TERM...(FRIDAY NIGHT THROUGH TUESDAY)
ISSUED AT 330 AM MDT WED AUG 27 2014
MILD AND MAINLY DRY WEATHER FRI NIGHT INTO SATURDAY AS A MINOR UPPER
RIDGE MOVES EAST ACROSS THE AREA. A QUICK-MOVING SHORTWAVE SHOULD
PASS MAINLY NORTH OF THE CWA LATE SAT BUT COULD BRING A FEW SHOWERS
TO MAINLY NORTHERN PARTS OF THE CWA THEN. MORE SIGNIFICANT UPPER TROF
WILL MOVE ACROSS SUNDAY BRINGING MORE WIDESPREAD SHOWERS AND A FEW
TSTMS. ECMWF MORE BULLISH WITH THIS SYSTEM WITH THE GFS CONSIDERABLY
WEAKER. MILD AND MAINLY DRY WEATHER RETURNS FOR MONDAY AND TUESDAY
AS THE CWA RESIDES ON THE SOUTHERN SIDE OF BROAD UPPER CYCLONIC FLOW
THAT WILL PROGRESS ACROSS THE NORTHERN PART OF THE COUNTRY.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z THURSDAY MORNING)
ISSUED AT 330 AM MDT WED AUG 27 2014
SHOULD SEE LOWERING CIGS ACROSS MANY AERODROMES THIS MORNING TO
MOSTLY MVFR AS SHOWERS AND A FEW TSTMS INCREASE IN COVERAGE WITH THE
APPROACH OF AN UPPER DISTURBANCE. SFC LOW WILL DEVELOP OVER SE
COLORADO THIS AFTERNOON TURNING WINDS ACROSS THE AREA TO A MORE
UPSLOPE DIRECTION. IMPROVING CONDITIONS EXPECTED OVER SE WY TONIGHT
BUT MVFR CIGS SHOULD HOLD ACROSS PARTS OF THE NEB PANHANDLE.
&&
.FIRE WEATHER...
ISSUED AT 252 AM MDT WED AUG 27 2014
A LOW PRESSURE SYSTEM OVER UTAH EARLY THIS MORNING WILL SLOWLY TRACK
EAST THROUGH COLORADO DURING THE NEXT 24 HOURS...AND INTO THE CENTRAL
PLAINS BY FRIDAY. NUMEROUS SHOWERS AND SCATTERED THUNDERSTORMS WILL
PRODUCE WETTING RAINFALL TODAY AND TONIGHT. DRIER AND WARMER WEATHER
WILL RETURN THURSDAY AND CONTINUE THROUGH SATURDAY...ALONG WITH GUSTY
WEST TO SOUTHWEST WINDS. THERE WILL BE A SLIGHT CHANCE OF SHOWERS
AND THUNDERSTORMS SUNDAY AND LABOR DAY WITH THE PASSAGE OF A UPPER
LEVEL TROUGH AND PACIFIC COLD FRONT.
&&
.CYS WATCHES/WARNINGS/ADVISORIES...
WY...NONE.
NE...NONE.
&&
$$
SHORT TERM...JAMSKI
LONG TERM...RE
AVIATION...RE
FIRE WEATHER...JAMSKI
AREA FORECAST DISCUSSION
NWS MELBOURNE FL
958 AM EDT WED AUG 27 2014
.DISCUSSION...
MORNING SOUNDINGS FROM KXMR AND KTBW CONTINUE TO SHOW A VERY DRY
AND STABLE AIRMASS ACROSS CENTRAL FLORIDA TODAY. LINGERING
MOISTURE AND 10-15 KT NORTH-NORTHEAST FLOW IN THE LOWER LEVELS IS
STILL BEING ABLE TO SQUEEZE OUT A FEW SHOWERS OVER THE COASTAL
WATERS WHICH ARE BEING STEERED ONSHORE THIS MORNING. HRRR MODEL
SHOWS ADDITIONAL ISOLATED SHOWERS POSSIBLE ALONG THE INLAND MOVING
EAST COAST SEA BREEZE THIS AFTERNOON. SO WILL KEEP A SLIGHT CHANCE
FOR SHOWERS MENTIONED IN THE FORECAST FOR TODAY. HOWEVER MOST
AREAS LOOK TO REMAIN DRY. HIGHS WILL RANGE FROM THE UPPER
80S/AROUND 90 DEGREES ALONG THE COAST UP TO THE LOW/MID 90S
INLAND WITH PARTLY SUNNY SKIES FORECAST.
&&
.AVIATION...VFR CONDS GENERALLY EXPECTED. A FEW ONSHORE MOVING
SHOWERS WILL OCCUR ALONG THE COAST THIS MORNING AND ADDITIONAL
ISOLATED SHOWERS POSSIBLE INLAND ALONG THE EAST COAST SEA BREEZE
THIS AFTERNOON.
&&
.MARINE...WEAKENING PRESSURE GRADIENT WILL ALLOW N/NE WINDS TO
DECREASE INTO TONIGHT. HOWEVER WIND SPEEDS UP TO AROUND 15 KNOTS
STILL POSSIBLE OFFSHORE THROUGH THIS AFTERNOON WITH LINGERING
SWELLS CONTRIBUTING TO SEAS UP TO 6-8 FEET. WILL MAINTAIN SMALL
CRAFT ADVISORY FOR SEAS OFFSHORE WITH SMALL CRAFT EXERCISE CAUTION
NEARSHORE.
&&
.MLB WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
AM...SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS UNTIL 4 AM EDT THURSDAY
FOR WATERS FROM FLAGLER BEACH TO VOLUSIA BREVARD COUNTY
LINE 20 TO 60 NM OFFSHORE-WATERS FROM SEBASTIAN INLET TO
JUPITER INLET 20 TO 60 NM OFFSHORE-WATERS FROM VOLUSIA
BREVARD COUNTY LINE TO SEBASTIAN INLET 20 TO 60 NM OFFSHORE.
&&
$$
WEITLICH/JOHNSON
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
622 AM CDT WED AUG 27 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 202 AM CDT WED AUG 27 2014
SUBTLE UPPER LEVEL DISTURBANCES EMBEDDED IN A SOUTHWEST FLOW WILL
CROSS THE CENTRAL PLAINS OVER THE NEXT 36 TO 48 HOURS AS THE MAIN
UPPER LEVEL TROUGH MOVES SLOWLY EAST ACROSS THE FOUR CORNERS
REGION. EARLIER THIS MORNING THE WATER VAPOR LOOP, AND 00Z
WEDNESDAY UPPER AIR ANALYSIS PLACED ONE OF THE UPPER WAVES WERE
LOCATED OVER NORTHEAST NEW MEXICO. RADAR MOSAIC AND SURFACE
OBSERVATION INDICATED SCATTERED SHOWERS AND THUNDERSTORMS WERE
OCCURRING AHEAD OF THIS FEATURE ACROSS THE OKLAHOMA AND TEXAS
PANHANDLE. NAM, GFS, AND HRRR WERE ALL IN GOOD AGREEMENT IN MOVING
THIS AREA OF PRECIPITATION ACROSS WESTERN KANSAS DURING THE EARLY
MORNING HOURS AND BASED ON 06Z VERIFICATION OF THE UPPER WAVE AND
AREA FAVORABLE FOR PRECIPITATION THESE MODELS APPEAR TO HAVE A
GOOD HANDLE ON THIS EARLY MORNING EVENT. WILL THEREFORE KEEP HIGH
CHANCE OR EVEN LIKELY WORDING FOR THUNDERSTORMS THROUGH AT LEAST
15Z ACROSS NORTH CENTRAL AND MUCH OF WESTERN KANSAS AS THE UPPER
WAVE PASSES.
AS THIS FIRST SYSTEM LIFTS NORTHEAST TOWARDS SOUTHERN NEBRASKA
LATER THIS MORNING...A SECOND UPPER LEVEL DISTURBANCE WILL BEGIN
TO APPROACH THE AREA FROM THE SOUTHWEST. THIS NEXT SYSTEM APPEARS
TO BE LOCATED NEAR THE NOSE OF AN 300MB JET STREAK AND IS
CURRENTLY FORECAST TO CROSS WESTERN KANSAS LATE THIS AFTERNOON AND
EARLY THIS EVENING. GIVEN THE LOCATION OF AN UPPER LEVEL JET LATE
TODAY/EARLY EVENING ALONG WITH MOISTURE, AND INSTABILITY AHEAD OF
THIS NEXT DISTURBANCE WILL INCREASE PRECIPITATION CHANCES DURING
THE AFTERNOON AND EARLY EVENING. MAIN HAZARD CURRENTLY APPEARS TO
BE PERIODS OF HEAVY RAINFALL, HOWEVER A FEW OF THE STRONGER
THUNDERSTORMS IN WEST CENTRAL AND PARTS OF NORTH CENTRAL KANSAS
MAY ALSO PRODUCE HAIL AND STRONG GUSTY WINDS.
AS FOR TEMPERATURES TODAY WILL UNDERCUT GUIDANCE AND TREND
TOWARDS WHAT THE 850MB 00Z THURSDAY MIX DOWN TEMPERATURES
SUGGESTED FOR HIGHS. GIVEN THE EXPECTED CLOUD COVER AND THE 00Z
850MB TEMPERATURES WILL FAVOR AFTERNOON TEMPERATURES MAINLY IN THE
MID 80S ACROSS WEST CENTRAL KANSAS AND UPPER 80S TO NEAR 90
ELSEWHERE. IN SOUTH CENTRAL KANSAS WHERE MORE SUN AND LESS CLOUDS
ARE EXPECTED WILL TREND SLIGHTLY WARMER.
.LONG TERM...(THURSDAY THROUGH TUESDAY)
ISSUED AT 306 AM CDT WED AUG 27 2014
AN UPPER LEVEL LOW WILL MOVE THROUGH THE CENTRAL ROCKIES THURSDAY
THEN THROUGH THE CENTRAL PLAINS FRIDAY BEFORE WEAKENING AND
EXITING INTO THE UPPER MISSISSIPPI VALLEY ON SATURDAY. THIS
FEATURE WILL HELP PUSH A SURFACE COLD FRONT THROUGH WESTERN KANSAS
THURSDAY INTO THURSDAY NIGHT. THE FRONT WILL THEN BE POSITIONED
ACROSS CENTRAL KANSAS ON FRIDAY. LOWER AND MID LEVELS OF THE
ATMOSPHERE WILL BE SATURATED AND WITH THE LIFT CREATED BY THIS
SYSTEM, MOSTLY CLOUDY SKIES ARE EXPECTED THROUGH FRIDAY. STORM
CHANCES WILL ALSO BE PRESENT THROUGH FRIDAY WITH THE BEST CHANCE
OCCURRING THURSDAY AFTERNOON INTO THURSDAY NIGHT WHEN THE COLD
FRONT MOVES ACROSS THE CWA. THUNDERSTORM CHANCES END FROM WEST TO
EAST ON FRIDAY THEN BE CONFINED ACROSS CENTRAL AND EASTERN KANSAS
BY SATURDAY. A DRIER PERIOD IS THEN EXPECTED THROUGH THIS WEEKEND
INTO THE BEGINNING OF NEXT WEEK AS A WEAK UPPER LEVEL RIDGE MOVING
THROUGH THE ROCKIES AND HIGH PRESSURE BUILDING ACROSS THE AREA AT
THE SURFACE. MEANWHILE, A UPPER LEVEL LONG WAVE TROUGH IS PROGGED
TO DIG INTO THE PACIFIC NORTHWEST AND INTER-MOUNTAIN WEST THIS
WEEKEND INTO THE FIRST PART OF NEXT WEEK, THEN MOVE INTO THE THE
NORTHERN PLAINS BY MID WEEK. THIS COULD BRING A CHANCE OF
THUNDERSTORMS TUESDAY INTO WEDNESDAY, HOWEVER, IT IS TOO FAR OUT
TO PIN POINT EXACTLY THE BEST LIFT WILL OCCUR. OTHERWISE EXPECT
PARTLY CLOUDY SKIES SATURDAY THROUGH THE MIDDLE OF NEXT WEEK. AS
FOR TEMPERATURES, HIGHS LOOK TO BE IN THE 80S THURSDAY THROUGH
SATURDAY THEN INCREASE INTO THE LOWER TO MID 90S ON SUNDAY. HIGHS
MONDAY THROUGH WEDNESDAY ARE FORECASTED TO RANGE FROM THE UPPER
80S ACROSS WEST CENTRAL KANSAS TO MID 90S ACROSS SOUTH CENTRAL
KANSAS. LOWS THROUGH THE EXTENDED PERIOD LOOK TO GENERALLY BE IN
THE 60S WITH A FEW LOWER 70S ACROSS SOUTH CENTRAL KANSAS MONDAY
AND TUESDAY MORNINGS.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z THURSDAY MORNING)
ISSUED AT 619 AM CDT WED AUG 27 2014
MVFR CONDITIONS WILL BE OBSERVED ACROSS THE DDC TERMINAL OVER THE
NEXT COUPLE OF HOURS AS LIGHT TO MODERATE RAIN REDUCE VISIBILITIESBELOW
5 MILES. OTHERWISE EXPECT VFR CONDITIONS ACROSS THE TAF SITES.
WINDS WILL GENERALLY BE FROM A SOUTHERLY DIRECTION AROUND 10 KNOTS
THIS MORNING INCREASING TO AROUND 13 KNOTS BY LATE MORNING WITH
HIGHER GUSTS. A CHANCE OF THUNDERSTORMS IS IN THE FORECAST LATE
THIS AFTERNOON INTO THIS EVENING AND HAVE PLACED A TEMPO GROUP TO
REFLECT THIS.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 90 67 86 64 / 60 50 50 50
GCK 87 66 84 63 / 50 60 50 60
EHA 87 64 83 62 / 40 50 40 40
LBL 91 67 86 65 / 40 50 40 40
HYS 88 68 85 66 / 50 60 50 70
P28 93 71 88 68 / 20 40 60 60
&&
.DDC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...BURGERT
LONG TERM...HOVORKA_42
AVIATION...HOVORKA_42
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
733 AM EDT WED AUG 27 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 349 AM EDT WED AUG 27 2014
MUCH OF THE FOCUS OF THE SHORT TERM FORECAST IS WITH THE SHORTWAVE
QUICKLY MOVING EAST-SOUTHEAST INTO THE UPPER GREAT LAKES REGION.
THE AXIS OF THE SHORTWAVE IS LOCATED IN NORTHERN MINNESOTA AT
07Z...BUT THERE ARE TWO AREAS OF SHOWERS AHEAD OF THIS WAVE...ONE
STRETCHING FROM ISLE ROYALE TO LITTLE FALLS MINNESOTA AND THE OTHER
FROM WESTERN MARQUETTE COUNTY TO EAU CLAIRE WISCONSIN. EVEN THOUGH
THE 00Z KMPX RAOB INDICATED DRY AIR BELOW THE CLOUDS BASE...RAIN
HAS BEEN REACHING THE GROUND UNDER MOST OF THE RADAR RETURNS AND
GENERALLY PRODUCING ANYWHERE FROM A TRACE TO 0.05IN OF RAIN AS IT
HAS MOVED THROUGH MINNESOTA AND NORTHWEST WISCONSIN. EXPECT THESE
SHOWERS TO CONTINUE TO THE EAST AS THE SHORTWAVE QUICKLY MOVES
THROUGH THE WEST HALF OF UPPER MICHIGAN BY 12Z AND OUT OF THE ENTIRE
AREA BY 15Z. THE 04Z/05Z HRRR RUNS HAVE HAD A DECENT HANDLE ON
PRECIP AND WEIGHTED THE POP FORECAST TOWARDS THAT FOR THE FIRST
6HRS. THEREFORE...HAVE SHOWN SCATTERED/ISOLATED SHOWERS MOVING
THROUGH THE CWA THIS MORNING AND QUICKLY COMING TO AN END FROM WEST
TO EAST. BEHIND THE SHORTWAVE...DRY AIR ASSOCIATED WITH A HIGH
CURRENTLY CENTERED IN MINNESOTA WILL QUICKLY MOVE OVER MUCH OF THE
AREA AND LEAD TO ANOTHER COOL DAY ACROSS THE U.P.
EXPECT SOME DIURNAL CLOUD DEVELOPMENT AFTER THE MID CLOUDS
DEPART...AS A POCKET OF MOISTURE AROUND 850MB OR 4KFT SEEN OVER LAKE
SUPERIOR THIS PAST EVENING AND KCMX OBS OVERNIGHT GRADUALLY SHIFTS
SOUTHEAST AND DISSIPATES. WITH THE LIGHT WEST-NORTHWEST FLOW IN THE
LOW LEVELS...EXPECT THE CLOUDS TO BE INLAND FROM LAKE SUPERIOR AND
GENERALLY OVER CENTRAL/EASTERN UPPER MICHIGAN. HIGHS TODAY WILL BE
SIMILAR TO YESTERDAY OVER THE WEST THIRD (MID-UPPER 60S) AND
SLIGHTLY COOLER OVER THE CENTRAL/EAST (65-71).
HIGH PRESSURE WILL REMAIN IN PLACE TONIGHT AND PRODUCE MOSTLY CLEAR
SKIES (JUST A FEW HIGH CLOUDS APPROACHING FROM THE SOUTHWEST AHEAD
OF THE NEXT SHORTWAVE). THE MOSTLY CLEAR SKIES...LIGHT WINDS...AND
PWATS AROUND 45 PERCENT OF NORMAL WILL LEAD TO A GOOD RADIATIONAL
COOLING NIGHT. HAVE THE INTERIOR LOCATIONS FALLING INTO THE LOWER
40S TO UPPER 30S...WHICH IS A LITTLE COOLER THAN THE PREVIOUS
FORECAST. WOULD NOT BE SURPRISED IF SOME OF THE TRADITIONAL COLD
RAWS SITES REACH THE MIDDLE 30S AND DID DROP A FEW OF THEM TO THOSE
VALUES (WHICH COULD LEAD TO SOME PATCHY FROST). WILL CONTINUE THE
MENTION OF PATCHY RADIATIONAL/GROUND FOG FOR TONIGHT...BUT DON/T
EXPECT IT TO BE TOO THICK DUE TO THE EXISTING DRY AIR. THE PLACES
WHERE IT SHOULD BE THE THICKEST WOULD BE IN ANY LOW SPOTS OR NEAR
LAKES (DUE TO THEIR WARMER WATER TEMPERATURES).
.LONG TERM...(THURSDAY THROUGH TUESDAY)
ISSUED AT 519 AM EDT WED AUG 27 2014
THRU THE BEGINNING OF THE UPCOMING WEEKEND...A LOW AMPLITUDE
PROGRESSIVE NRN STREAM FLOW REGIME WILL PREVAIL ACROSS SRN CANADA. A
WEAKER SRN BRANCH FLOW ACROSS THE CONUS WILL CAUSE ISSUES WITH
REGARD TO PCPN OVER THE UPPER LAKES...DEPENDING ON INTERACTION OF
SHORTWAVES WITH THE MORE PROGRESSIVE FLOW TO THE N. RIGHT NOW...THE
SRN BRANCH FEATURES A TROF AND WELL-DEFINED SHORTWAVE OVER THE SRN
ROCKIES. EARLY NEXT WEEK...FLOW WILL AMPLIFY SOME AS A MORE
SUBSTANTIAL TROF MOVES INTO THE NW CONUS AND THEN SHIFTS EASTWARD.
OVERALL...THIS PATTERN WILL SUPPORT TEMPS GENERALLY AROUND NORMAL TO
A BIT BLO OVER THE NEXT FEW DAYS. BRIEF WARMING WILL OCCUR EARLY
NEXT WEEK AHEAD OF THE MORE SUBSTANTIAL TROF PROGRESSING E ACROSS
THE NW AND NCNTRL CONUS. PCPN FCST IS QUITE UNCERTAIN. THERE IS THE
POTENTIAL FOR AT LEAST A COUPLE OF ROUNDS OF PCPN THRU THE UPCOMING
WEEKEND...DEPENDING ON EVOLUTION OF SRN BRANCH SHORTWAVES. ANOTHER
PERIOD OF PCPN SHOULD OCCUR EARLY NEXT WEEK AS COLD FRONT SWEEPS
ACROSS THE AREA IN ASSOCIATION WITH AFOREMENTIONED TROF MOVING
ACROSS THE NW/NCNTRL CONUS.
BEGINNING THU/FRI...ATTENTION TURNS TO SHORTWAVE LIFTING OUT OF THE
SRN BRANCH TROF CURRENTLY OVER THE SRN ROCKIES. WITH NRN STREAM
TROFS MOVING ACROSS THE CANADIAN ROCKIES AND QUEBEC/NEW ENGLAND...
THERE WILL BE AN OPPORTUNITY FOR THE SRN BRANCH SHORTWAVE TO MAKE
SOME NORTHWARD PROGRESS. MODELS HAVE OVERALL MOVED INTO BETTER
AGREEMENT ON WAA/MOISTURE ADVECTION LIFTING N AND SPREADING PCPN
INTO UPPER MI THU NIGHT/FRI. HOWEVER...THERE ARE STILL SOME
DIFFERENCES AS THE GEM/ECMWF/NAM ARE MORE AGGRESSIVE SPREADING MAIN
AREA OF PCPN MORE SQUARELY ACROSS THE FCST AREA. THE GFS IS FOCUSED
MORE TO THE S AND E. GIVEN TRENDS AND GFS SOMEWHAT ON ITS OWN...
RAISED POPS SOME FOR LATER THU NIGHT/FRI MORNING WITH LIKELY POPS
FROM THE SCNTRL TO THE ERN FCST AREA. WILL NEED TO CONTINUE UPWARD
TREND IF NEXT ROUND OF MODELS STAYS ON TRACK. INSTABILITY IS RATHER
LIMITED. ONLY INCLUDED THUNDER SCNTRL AND E. AFTER SOME PATCHY FOG
EARLY THU...SUNSHINE WILL GIVE WAY TO INCREASING HIGH CLOUDS. MIXING
TO 850-800MB ON FCST SOUNDINGS SUGGEST HIGH TEMPS THU WILL BE MOSTLY
IN THE LOW/MID 70S AWAY FROM LAKE COOLING.
OVER THE WEEKEND...FCST HAS BECOME MORE UNCERTAIN AS THERE IS A
TREND FOR THE MAIN ENERGY CURRENTLY IN THE SRN ROCKIES TROF TO LIFT
FARTHER N. ASSOCIATED WEAK SFC WAVE IS FCST TO TRACK ACROSS SRN WI
AND THRU NRN LWR MI. GIVEN TRENDS ALONG WITH DECENT AGREEMENT AMONG
00Z MEDIUM RANGE GUIDANCE...WILL LINGER CHC POPS OVER THE SE HALF OF
THE FCST AREA FRI NIGHT...THEN SPREAD CHC POPS BACK N AND W SAT/SAT
NIGHT. LOOKS LIKE SUN SHOULD DRY OUT WITH SHORTWAVE RIDGE ARRIVING
BTWN DEPARTING SHORTWAVE AND AHEAD OF MORE SIGNIFICANT TROF
DEVELOPING INTO THE NW CONUS.
AS THE MORE SUBSTANTIAL TROF OVER THE NW CONUS SHIFTS EASTWARD EARLY
NEXT WEEK...A COLD FRONT WILL SWEEP E ACROSS THE GREAT LAKES...
BRINGING A DECENT POTENTIAL FOR SHRA/TSRA. FOR THIS FAR OUT IN THE
MODEL RUNS...AGREEMENT IS GOOD ON TIMING FRONT. THE ECMWF HAS
NOTABLY TRENDED FASTER TOWARD THE GFS WHICH IS TYPICALLY MORE
PROGRESSIVE...AND THE GEM OFFERS SIMILAR TIMING. THESE LATEST RUNS
SUGGEST FRONT CROSSING UPPER MI MON AFTN/NIGHT. SO IT LOOKS LIKE
LABOR DAY MIGHT TURN WET WITH SHRA AND TSTMS SPREADING E ACROSS THE
AREA.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z THURSDAY MORNING)
ISSUED AT 733 AM EDT WED AUG 27 2014
VFR CONDITIONS WILL PREVAIL AT ALL THREE SITES THROUGH THE TAF
PERIOD. THE UPPER LEVEL DISTURBANCE THAT PRODUCE A FEW SHOWERS AT
THE TAF SITES EARLY THIS MORNING IS QUICKLY DEPARTING THE REGION
AND SHOULD BE EAST OF KSAW BY TAF VALID TIME. BEHIND THIS
WAVE...THERE COULD BE SOME LINGERING DIURNAL CLOUDS...ESPECIALLY AT
KSAW/KCMX DUE TO THEIR CLOSER PROXIMITY TO THE MOISTURE. TONIGHT
WILL BE CLEAR...WHICH COULD LEAD TO VERY PATCHY GROUND FOG OVER
CENTRAL UPPER MICHIGAN. DUE TO THE SHALLOW NATURE OF THIS
FOG...HAVE LEFT KSAW VISIBILITIES AT VFR.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 349 AM EDT WED AUG 27 2014
HIGH PRESSURE MOVING THROUGH THE UPPER GREAT LAKES REGION TODAY AND
THURSDAY WILL LEAD TO WINDS STAYING BELOW 15KTS. THIS HIGH WILL
SHIFT EAST THURSDAY NIGHT...ALLOWING A COUPLE WEAK SURFACE TROUGHS
TO MOVE THROUGH THE REGION. THE WEAK PRESSURE GRADIENT ASSOCIATED
WITH THESE TROUGHS WILL KEEP WINDS BELOW 20KTS.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...SRF
LONG TERM...ROLFSON
AVIATION...SRF
MARINE...SRF
AREA FORECAST DISCUSSION
NWS BISMARCK ND
950 AM CDT WED AUG 27 2014
.UPDATE...
ISSUED AT 950 AM CDT WED AUG 27 2014
LATEST SATELLITE SHOWS QUITE A BIT OF FOG REMAINING OVER SOUTHWEST
AND SOUTH CENTRAL NORTH DAKOTA. HOWEVER...LOOKS LIKE IT IS
DISSIPATING QUICKLY THUS WILL LIKELY DROP THE ADVISORY AFTER
TAKING A LOOK AT THE 10 AM OBSERVATIONS. OTHERWISE NO SIGNIFICANT
ISSUES TO THE GOING FORECAST. WILL UPDATE TEXT PRODUCTS WILL BE
SENT WITH THE EXPIRATION/CANCELLATION OF THE DENSE FOG ADVISORY.
UPDATE ISSUED AT 623 AM CDT WED AUG 27 2014
REFINED THE FOG AREAS TO REFLECT FOG OVER MOST OF THE WEST AND
CENTRAL THIS MORNING. LEFT THE ADVISORY AREA IN PLACE.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 431 AM CDT WED AUG 27 2014
FOR THE NEAR TERM/EARLY THIS MORNING...THE CURRENT FOG/STRATUS
IMAGERY LOOP IN COMBINATION WITH SURFACE OBSERVATIONS SHOWS DENSE
FOG EXPANDING OVER MOST OF CENTRAL NORTH DAKOTA. BASED ON CURRENT
VISIBILITY TRENDS AND LATEST HRRR VISIBILITY FORECAST...HAVE
ISSUED A DENSE FOG ADVISORY FOR MOST OF CENTRAL NORTH DAKOTA
THROUGH LATE WEDNESDAY MORNING.
OTHERWISE...A CLEAR SKY DOMINATES WEST AND NORTH WITH THE LATEST
WATER VAPOR IMAGERY SHOWING SUBSIDENCE BEHIND A NORTHERN STREAM
SHORTWAVE NOW INTO MINNESOTA. SPLIT FLOW CONTINUES WITH THE
SOUTHERN BRANCH EXTENDING FROM THE GREAT BASIN INTO SOUTH DAKOTA.
AN UPPER LOW/TROUGH WAS SEEN OVER WESTERN NEVADA EARLY THIS MORNING.
EXPECTING PLENTY OF SUNSHINE TODAY WITH TEMPERATURES WARMING INTO
THE 70S...AND LOWER 80S IN THE FAR WEST. ALL MODEL GUIDANCE...WITH
THE EXCEPTION OF THE GFS...ARE IN AGREEMENT THAT THE SOUTHERN
BRANCH MAKES A RETURN INTO SOUTHERN NORTH DAKOTA WEDNESDAY NIGHT.
AS THE AFOREMENTIONED GREAT BASIN LOW/TROUGH SHIFTS EAST...A
SURFACE LOW WILL TAKE SHAPE OVER NEBRASKA AND SOUTH DAKOTA LATER
TODAY INTO TONIGHT. LATEST TRENDS INDICATE THE NORTHERN FRINGE OF
PRECIPITATION WILL REACH THE JAMES RIVER VALLEY BETWEEN 06Z AND
12Z THURSDAY. AFTER COLLABORATING WITH ABERDEEN AND GRAND
FORKS...HAVE INTRODUCED A SLIGHT CHANCE MENTION FOR SHOWERS AND WILL
LET SUBSEQUENT SHIFTS LOOK AT THE LATEST DATA TO FINE TUNE.
.LONG TERM...(THURSDAY THROUGH TUESDAY)
ISSUED AT 431 AM CDT WED AUG 27 2014
DURING THIS PERIOD THERE WILL BE SEVERAL COLD FRONTAL PASSAGES THAT
WILL BRING SOME ACTIVE WEATHER TO THE REGION OVER THE LABOR DAY
WEEKEND. FIRST...THE REMNANTS OF AN UPPER LEVEL LOW WILL TRACK SOUTH
OF THE STATE THURSDAY. WHILE THIS FEATURE WILL IMPACT THE AREAS
SOUTH OF THE STATE WITH SEVERAL LARGE MCS TYPE CONVECTIVE
SYSTEMS...THERE WILL BE SOME RESIDUAL MOISTURE PULLED INTO THE
STATE...MAINLY ACROSS THE JAMES RIVER VALLEY THURSDAY MORNING. BUT
THERE WILL LIKELY BE MORE CLOUDS THROUGH THE DAY THURSDAY THAN
PREVIOUSLY THOUGHT ACROSS A LARGE PORTION OF SOUTHERN AND EASTERN
NORTH DAKOTA. AFTER THIS A COLD FRONT WILL ENTER THE NORTHWEST
SUPPORTED BY A RATHER WEAK LEADING SHORTWAVE TROUGH AHEAD OF A MORE
SIGNIFICANT SHORTWAVE STILL LINGERING ACROSS THE NORTHWEST US FRIDAY.
OVERALL...HAVE DOWN PLAYED THE POPS THURSDAY NIGHT AND
FRIDAY...WAITING INSTEAD FOR THE MORE SIGNIFICANT SHORTWAVE DUE IN
SATURDAY NIGHT AND SUNDAY. WITH THIS NEXT SYSTEM WILL SEE MORE
SIGNIFICANT PRECIPITATION WITH STRONGER WARM/COLD FRONTAL PASSAGES.
SO THE HOLIDAY WEEKEND SHOULD BE A BIT SOGGY SATURDAY NIGHT WITH
SCATTERED SHOWERS ON SUNDAY. COOL CYCLONIC FLOW ALOFT SHOULD
MAINTAIN SLIGHT THREAT FOR THUNDERSTORMS MONDAY AND TUESDAY.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z THURSDAY MORNING)
ISSUED AT 950 AM CDT WED AUG 27 2014
FOG LIFTING AT KBIS AND KJMS AND SHOULD BE VFR BY 15 UTC OR
SHORTLY THEREAFTER. VFR CONDITIONS EXPECTED THE REST OF THE
DAY...THEN CLOUDS/LOW VFR CIGS RETURN TO KBIS/KJMS WEDNESDAY
NIGHT...WITH A VCSH AT KJMS AFTER 08Z THURSDAY.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
DENSE FOG ADVISORY UNTIL 11 AM CDT /10 AM MDT/ THIS MORNING FOR
NDZ019>023-025-034>037-041-042-044>048-050-051.
&&
$$
UPDATE...TWH
SHORT TERM...KS
LONG TERM...WAA
AVIATION...TWH
AREA FORECAST DISCUSSION
NWS BISMARCK ND
627 AM CDT WED AUG 27 2014
.UPDATE...
ISSUED AT 623 AM CDT WED AUG 27 2014
REFINED THE FOG AREAS TO REFLECT FOG OVER MOST OF THE WEST AND
CENTRAL THIS MORNING. LEFT THE ADVISORY AREA IN PLACE.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 431 AM CDT WED AUG 27 2014
FOR THE NEAR TERM/EARLY THIS MORNING...THE CURRENT FOG/STRATUS
IMAGERY LOOP IN COMBINATION WITH SURFACE OBSERVATIONS SHOWS DENSE
FOG EXPANDING OVER MOST OF CENTRAL NORTH DAKOTA. BASED ON CURRENT
VISIBILITY TRENDS AND LATEST HRRR VISIBILITY FORECAST...HAVE
ISSUED A DENSE FOG ADVISORY FOR MOST OF CENTRAL NORTH DAKOTA
THROUGH LATE WEDNESDAY MORNING.
OTHERWISE...A CLEAR SKY DOMINATES WEST AND NORTH WITH THE LATEST
WATER VAPOR IMAGERY SHOWING SUBSIDENCE BEHIND A NORTHERN STREAM
SHORTWAVE NOW INTO MINNESOTA. SPLIT FLOW CONTINUES WITH THE
SOUTHERN BRANCH EXTENDING FROM THE GREAT BASIN INTO SOUTH DAKOTA.
AN UPPER LOW/TROUGH WAS SEEN OVER WESTERN NEVADA EARLY THIS MORNING.
EXPECTING PLENTY OF SUNSHINE TODAY WITH TEMPERATURES WARMING INTO
THE 70S...AND LOWER 80S IN THE FAR WEST. ALL MODEL GUIDANCE...WITH
THE EXCEPTION OF THE GFS...ARE IN AGREEMENT THAT THE SOUTHERN
BRANCH MAKES A RETURN INTO SOUTHERN NORTH DAKOTA WEDNESDAY NIGHT.
AS THE AFOREMENTIONED GREAT BASIN LOW/TROUGH SHIFTS EAST...A
SURFACE LOW WILL TAKE SHAPE OVER NEBRASKA AND SOUTH DAKOTA LATER
TODAY INTO TONIGHT. LATEST TRENDS INDICATE THE NORTHERN FRINGE OF
PRECIPITATION WILL REACH THE JAMES RIVER VALLEY BETWEEN 06Z AND
12Z THURSDAY. AFTER COLLABORATING WITH ABERDEEN AND GRAND
FORKS...HAVE INTRODUCED A SLIGHT CHANCE MENTION FOR SHOWERS AND WILL
LET SUBSEQUENT SHIFTS LOOK AT THE LATEST DATA TO FINE TUNE.
.LONG TERM...(THURSDAY THROUGH TUESDAY)
ISSUED AT 431 AM CDT WED AUG 27 2014
DURING THIS PERIOD THERE WILL BE SEVERAL COLD FRONTAL PASSAGES THAT
WILL BRING SOME ACTIVE WEATHER TO THE REGION OVER THE LABOR DAY
WEEKEND. FIRST...THE REMNANTS OF AN UPPER LEVEL LOW WILL TRACK SOUTH
OF THE STATE THURSDAY. WHILE THIS FEATURE WILL IMPACT THE AREAS
SOUTH OF THE STATE WITH SEVERAL LARGE MCS TYPE CONVECTIVE
SYSTEMS...THERE WILL BE SOME RESIDUAL MOISTURE PULLED INTO THE
STATE...MAINLY ACROSS THE JAMES RIVER VALLEY THURSDAY MORNING. BUT
THERE WILL LIKELY BE MORE CLOUDS THROUGH THE DAY THURSDAY THAN
PREVIOUSLY THOUGHT ACROSS A LARGE PORTION OF SOUTHERN AND EASTERN
NORTH DAKOTA. AFTER THIS A COLD FRONT WILL ENTER THE NORTHWEST
SUPPORTED BY A RATHER WEAK LEADING SHORTWAVE TROUGH AHEAD OF A MORE
SIGNIFICANT SHORTWAVE STILL LINGERING ACROSS THE NORTHWEST US FRIDAY.
OVERALL...HAVE DOWN PLAYED THE POPS THURSDAY NIGHT AND
FRIDAY...WAITING INSTEAD FOR THE MORE SIGNIFICANT SHORTWAVE DUE IN
SATURDAY NIGHT AND SUNDAY. WITH THIS NEXT SYSTEM WILL SEE MORE
SIGNIFICANT PRECIPITATION WITH STRONGER WARM/COLD FRONTAL PASSAGES.
SO THE HOLIDAY WEEKEND SHOULD BE A BIT SOGGY SATURDAY NIGHT WITH
SCATTERED SHOWERS ON SUNDAY. COOL CYCLONIC FLOW ALOFT SHOULD
MAINTAIN SLIGHT THREAT FOR THUNDERSTORMS MONDAY AND TUESDAY.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z THURSDAY MORNING)
ISSUED AT 623 AM CDT WED AUG 27 2014
AREAS OF DENSE FOG FROM KBIS TO KJMS WILL POSE AS THE HIGHEST IMPACT
TO AVIATION THROUGH 14Z WEDNESDAY WITH VLIFR CIGS/VSBYS. FROM 14Z
THROUGH 16Z EXPECT A GRADUAL IMPROVEMENT TO MVFR THEN VFR. KDIK WILL
LIKELY SEE A BRIEF PERIOD OF LIFR CIGS AND MVFR VSBYS THROUGH 15Z.
VFR CONDITIONS EXPECTED THE REST OF THE DAY...THEN CLOUDS/LOW VFR
CIGS RETURN TO KBIS/KJMS WEDNESDAY NIGHT...WITH A VCSH AT KJMS AFTER
08Z THURSDAY.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
DENSE FOG ADVISORY UNTIL 11 AM CDT /10 AM MDT/ THIS MORNING FOR
NDZ019>023-025-034>037-041-042-044>048-050-051.
&&
$$
UPDATE...WAA
SHORT TERM...KS
LONG TERM...WAA
AVIATION...WAA
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
1011 AM EDT WED AUG 27 2014
.SYNOPSIS...
A COLD FRONT WILL MOVE ACROSS THE REGION THIS AFTERNOON AND
PROVIDE A FOCUS FOR THUNDERSTORMS. HIGH PRESSURE WILL ARRIVE
BEHIND THE FRONT AND BRING DRY WEATHER TO THE AREA THROUGH THE END
OF THE WEEK. ABOVE NORMAL TEMPERATURES AND INCREASINGLY HUMID
CONDITIONS ARE FORECAST OVER THE LABOR DAY HOLIDAY WEEKEND AND
INTO THE FIRST WEEK OF SEPTEMBER.
&&
.NEAR TERM /THROUGH TONIGHT/...
10 AM UPDATE...
PATCHY CLOUDS OVER MOST OF THE AREA AT THIS POINT WITH LITTLE TO
NO DIURNAL CU DEVELOPMENT. CONVECTIVE TEMPS SHOULD BE REACHED
FAIRLY SOON...THOUGH. SOLID CLOUD COVER IN THE NRN TIER IS
STARTING TO SHOW SIGNS OF BREAKING UP A BIT. BUT THE FRONT IS MOST
LIKELY THE THIN LINE WHICH IS VISIBLE ON KBUF RADAR AS IT
COINCIDES WITH THE MOST NOTICABLE WIND SHIFT. LATEST NAM AND THE
RAP AND HRRR ALL PRODUCE ISOLD/SCT SHRA/TSRA THIS AFTERNOON AND
EARLY EVENING AS THE FRONT PUSHES THROUGH. FEW CHANGES TO THE
POPS/WX GRIDS...EXCEPT FOR A LITTLE NUDGE DOWNWARD TO THE NW WITH
THE COOLER AIR AND FROPA WHICH SHOULD HAPPEN SOON. SPC CONTINUES
TO MENTION THE AREA IN THE DAY1 OUTLOOK FOR ALL THE REASONS
OUTLINED BELOW. ITS A WAITING GAME AT THIS POINT. MORE ACTIVITY
CENTERED ON THE NERN MTS AND POCONOS AND THE LAURELS THIS
AFTN/EVENING...WITH PERHAPS A LULL IN THE CENTRAL MTS WITH
DEWPOINTS PERHAPS LOWERING SLIGHTLY DUE TO MIXING BEFORE FROPA.
THE HURRICANE OFF THE COAST COULD ALSO CONTRIBUTE TO SOME TINY
BIT OF CONVECTIVE SUPPRESSION LOCALLY - BUT IT IS A LITTLE TOO FAR
AWAY FOR THAT TO BE A BIG FACTOR.
PREV...
PATCHY FOG IN THE RIVER/STREAM VALLEYS OF SCENTRL/SERN PA WILL
ERODE SHORTLY AFTER SUNRISE WITH LCL VISBYS IMPROVING BY 14Z.
CLOUDS ARE INCREASING OVER THE NW MTNS IN ADVANCE OF SFC COLD
FRONT SHIFTING SEWD FROM THE LAKE ERIE SHORELINE.
A LOW AMPLITUDE UPPER TROUGH OVER THE GREAT LAKES REGION THIS
MORNING WILL TRANSLATE EWD INTO THE NORTHEAST STATES TONIGHT AND
MOVE OFFSHORE DURING THE D2 PERIOD. AT THE SFC...A COLD FRONT
ANALYZED FROM THE ST. LAWRENCE VLY SWWD BACK ACRS THE LWR LKS
WILL PUSH SEWD ACRS CENTRAL PA THIS AFTN BEFORE SHIFTING SOUTH OF
THE MASON DIXON LINE AFTER 00Z. THE GLOBAL MODELS ARE WELL
CLUSTERED WITH THE UPPER TROUGH AND ASSOCIATED COLD FRONT CROSSING
THE NORTHEAST...WITH A NON-NAM CONSENSUS SOLUTION PREFERRED BY WPC
AS IT APPEARS TO BE STRONGER ALOFT AND A TAD SLOWER WITH THE
ADVANCE OF THE SFC FRONT.
THE MAIN FCST CONCERN IN THE NEAR TERM IS THE POTENTIAL FOR
STRONG TO LOCALLY SVR STORMS THIS AFTN. MODELS ADVECT RICH BLYR
MSTR EWD FROM THE OH VLY INTO CENTRAL PA IN ADVANCE OF THE SFC
COLD FRONT...WITH 60-65F DEWPOINTS PROGGED BY THE CONSENSUS
GUIDANCE. THE NAM IS LKLY TOO MOIST WITH LOW 70S DEWPOINTS.
STRONG HEATING AND DESTABILIZATION WILL LEAD TO MU CAPES IN
EXCESS OF 1000 J/KG ALONG A NARROW CORRIDOR PRECEDING THE COLD
FRONT. THE LOW-MID LVL BACKGROUND WIND FIELDS WILL NOT BE
PARTICULARLY STRONG...AND THE BEST DEEP SHEAR LAGS THE FRONT.
HOWEVER...A FEW CELLS CAPABLE OF PRODUCING SMALL TO MARGINALLY
SEVERE HAIL AND LOCALLY STRONG TO DMGG WIND GUSTS WILL BE POSSIBLE
GIVEN COMBO OF "SUFFICIENT" SHEAR AND DECENT INSTABILITY. THE D1
SPC OUTLOOK PLACES THE ERN ZONES IN THE CATEGORICAL SEE TEXT WITH
5% SVR PROBS BUT COULD SEE AN ISOLD SVR STORM FURTHER WEST ACROSS
S-CENTRAL PA TO THE LAUREL HIGHLANDS. CONVECTIVE ACTIVITY SHOULD
WEAKEN QUICKLY WITH THE LOSS OF DAYTIME HEATING AND EVENTUALLY
DISSIPATE/SHIFT S-SEWD AFTER MIDNIGHT.
AFTERNOON TEMPS WILL APPROACH 90F FROM THE SCNTRL RIDGE/VALLEY
REGION INTO THE LWR SUSQ VLY...WITH UPPER 70S TO LOW 80S COMMON
IN THE NW/NCNTRL HIGH TERRAIN.
&&
.SHORT TERM /THURSDAY THROUGH THURSDAY NIGHT/...
HIGH PRESSURE AND MUCH DRIER AIR WITH LOW/COMFORTABLE HUMIDITY
WILL OVERSPREAD THE AREA ON THURSDAY. ENS DATA SHOWS TEMPS ALOFT
SLIGHTLY BLW NORMAL OVER NRN/NERN PA WHICH SHOULD PROMOTE AFTN
CU/SC CLOUDS. TEMPS RANGE FROM AROUND 70F IN THE NW TO 80F IN THE
SE. THU NGT LOOKS SEASONABLY COOL WITH VALLEY FOG PROBABLE UNDER
SFC RIDGE WITH M/CLR SKIES AND NEARLY CALM WINDS. WAA CLOUDS MAY
IMPACT MIN TEMP FCST BUT FOR NOW SEE NO REASON TO DEVIATE FROM
CONSENSUS GUIDANCE.
&&
.LONG TERM /FRIDAY THROUGH TUESDAY/...
MEDIUM RANGE FLOW PATTERN ACRS THE CONUS WILL FEATURE TROUGHING
IN THE WEST AND FAIRLY HIGH HEIGHTS FCST TO PREVAIL OVER THE EAST
(FOR A CHANGE) SUPPORTED BY SUBTROPICAL RIDGE ANCHORED OVER THE
SOUTHEAST. HIGH PRESSURE CENTERED OVER UPSTATE NY AT THE START OF
THE PERIOD WILL MOVE OFF THE NRN NEW ENGLAND COAST ON SATURDAY AS
TODAYS FRONTAL BOUNDARY PIVOTS BACK NWD AS A WARM FRONT...IN
RESPONSE TO SHORTWAVE/SFC WAVE FCST TO TRACK NEWD FROM THE ERN
PLAINS/MS VLY. OVER THE PAST 12-24 HOURS THE LATEST GUIDANCE HAS
TRENDED NWD WITH SFC LOW TRACKS THRU THE GREAT LAKES AROUND D4/SUN
AND WITH LEADING FRONTAL BOUNDARY WHICH IS NOW PROGGED BY WPC TO
STAY NORTH OF PA. A MORE DEFINED COLD FRONT SHOULD APPROACH THE
AREA BY THE MIDDLE OF NEXT WEEK.
A RATHER MOIST RETURN FLOW AROUND SOUTHEAST RIDGE AND AHEAD MID
LVL SHORTWV TRACKING NEWD FROM THE ERN PLAINS/MS VLY ALONG WITH
INTERACTION WITH ASSOCIATED SFC WAVE/WAVY LEADING FRONTAL ZONE
SHOULD SPELL AN INCREASING PROBABILITY/OPPORTUNITY FOR RAIN INTO
THE WEEKEND. HOWEVER CONFIDENCE IN PCPN DETAILS (I.E. POPS) IS
MEDIUM AT BEST DUE TO MODEL SPREAD/DEPENDENCE ON SMALLER SCALE
FEATURES. THE FCST MAY BE PERCEIVED AS SOMEWHAT PESSIMISTIC WITH
NEARLY DAILY CHC FOR SHWRS/TSTMS HOWEVER PCPN WILL CERTAINLY NOT
BE CONTINUOUS WITH PERIODS OF DRY WX MIXED IN BTWN GENERALLY SCT
AND LARGELY DISORGANIZED/WEAKLY FORCED PCPN.
THERE IS HIGHER CONFIDENCE IN A WARMING TREND WITH MAX TEMPS 5-10F
ABOVE NORMAL OVER THE WEEKEND AND INTO THE FIRST WEEK OF SEPT.
&&
.AVIATION /14Z WEDNESDAY THROUGH SUNDAY/...
LEADING EDGE OF STRATO CU AND LOW-END ALTO CU ASSOCIATED WITH AN
AXIS OF MUCH HIGHER PWAT AIR /NEAR 1.75 INCHES FROM NERN OHIO TO
SWRN NEW YORK/ WERE DRIFTING INTO THE CENTRAL RIDGE AND VALLEY
REGION AT SUNRISE...WHILE SKIES WERE MAINLY CLEAR ACROSS THE
SOUTHEASTERN HALF OF THE STATE. LIGHT AND VARIABLE...TO LIGHT
SOUTHWESTERLY WIND WAS NOTED AT ALL AIRFIELDS.
SFC COLD FRONT WAS SLIDING JUST SE OF THE I-90 CORRIDOR FROM KCLE
TO KERI AND KROC ATTM. CLOUD BASES AT KBFD AND KJST SHOULD DIP
INTO THE MVFR RANGE AT TIMES LATER THIS MORNING AND EARLY THIS
AFTERNOON /WITH SOME OCNL IFR POSSIBLE AT BRADFORD BETWEEN
11-14Z/.
THE COLD FRONT WILL DRIFT SLOWLY SE AND CROSS CENTRAL PA AIRFIELDS
DURING THE LATE AFTERNOON HOURS...BEFORE REACHING THE LOWER
SUSQUEHANNA VALLEY /KMDT AND KLNS/ LATER THIS EVENING.
INSTABILITY AND MOISTURE WILL BE QUITE HIGH AHEAD OF THE COLD
FRONT...SO INCLUDED VCTS FOR ABOUT A 4-HOUR PERIOD PRECEDING THE
FRONTAL PASSAGE. BRIEF MVFR CONDITIONS ARE POSSIBLE IN THE
THUNDERSTORMS.
MAINLY VFR IS EXPECTED TONIGHT INTO THURSDAY IN THE WAKE OF THE
CFROPA. A 6-10 HOUR PERIOD OF NW WINDS AVERAGE 8-10 KTS...WITH GUSTS
IN THE MID-UPPER TEENS IS EXPECTED LATE TODAY AND TONIGHT IN THE
MDTLY TIGHT LLVL PRESSURE GRADIENT FOLLOWING THE COLD FRONT.
OUTLOOK...
THU-FRI...LATE NIGHT-EARLY MORNING RESTRICTIONS IN FOG
POSSIBLE...OTHERWISE VFR.
SAT-SUN...MAINLY VFR. CHC OF AFTERNOON SHOWERS/ISOLD TSTMS.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...DANGELO/STEINBUGL
NEAR TERM...DANGELO/STEINBUGL
SHORT TERM...STEINBUGL
LONG TERM...STEINBUGL
AVIATION...DANGELO/LAMBERT
AREA FORECAST DISCUSSION
NWS NASHVILLE TN
1016 AM CDT WED AUG 27 2014
.UPDATE...
LATEST VISIBLE SATELLITE IMAGERY SHOWS MOSTLY CLEAR SKIES WITH
CUMULUS DEVELOPMENT UNDERWAY ACROSS CENTRAL PARTS OF THE MID STATE
AND THE PLATEAU ALONG WITH SOME CIRRUS MOVING ACROSS. TEMPERATURES
RISING QUICKLY AND CURRENTLY IN THE UPPER 70S EAST TO MID 80S
ELSEWHERE. DEWPOINT CURRENTLY IN THE MID 60S TO MID 70S WILL MIX
OUT SOME OVER EASTERN HALF OF THE AREA THIS AFTERNOON...BUT STILL
ANTICIPATING A HOT AND HUMID DAY ON TAP FOR MOST LOCATIONS AND NO
CHANGES WERE MADE TO TEMPS. STILL CANNOT RULE OUT AN ISOLATED
SHOWER OR STORM OVER NORTHWEST ZONES WHERE DEEPER MOISTURE IS
PRESENT...AND ADJUSTED POPS SOMEWHAT BASED ON THE LATEST HRRR
MODEL.
SHAMBURGER
&&
.PREV DISCUSSION... /ISSUED 526 AM CDT WED AUG 27 2014/
UPDATE...FOR 12Z TAFS.
AVIATION...
MORELESS A REPEAT OF THE PAST FEW DAYS WITH CONVECTION TODAY
MAINLY ACROSS THE NORTHWEST. EARLY MORNING FOG EXPECTED TO CLEAR
14-15Z LEAVING VFR CONDITIONS THROUGHOUT THE DAY AND INTO THE
EVENING. FOG IS EXPECTED TO REDEVELOP LATE EVENING CSV...THEN
AGAIN OVERNIGHT CKV/BNA. CONDITIONS LIKELY TO DROP BRIEFLY TO
IFR CSV/CKV 06-13Z THU.
PREV DISCUSSION... /ISSUED 345 AM CDT WED AUG 27 2014
UPPER RIDGING IN CONTROL ACROSS THE SOUTHEASTERN U.S.. AT THE
SFC...HIGH PRESSURE IS LOCATED OVER THE GREAT LAKES REGION. THIS
FEATURE IS LARGE ENOUGH TO CONTROL OUR WEATHER AND A LIGHT NE FLOW
IS EXPECTED TODAY. ON THURSDAY...THE UPPER HIGH WILL BUILD SE TOWARD
NRN FL WITH A RIDGE AXIS EXTENDING NW ACROSS TN. ALL OF THIS RIDGING
WILL ACT TO IMPEDE ANY LOW LEVEL BOUNDARY INFLUENCE. CONVECTIVE
PARAMETERS SHOW VERY LITTLE CHANCE OF CONVECTION FOR TODAY. BUT...WE
DO SEE AN INCREASE IN CAPE VALUES ON THU AFTERNOON...BUT THIS IS
ACROSS THE NORTH ONLY. SO...WILL INCLUDE A SLIGHT CHANCE OF AFT
SHOWERS AND TSTMS. FURTHERMORE...THE HRRR IS SHOWING SOME AFT
DEVELOPMENT ACROSS THE KY AREA THIS AFTERNOON. MID/UPPER LEVEL
FLOW PATTERN DICTATES THAT THIS ACTIVITY WILL MOVE SE.
THEREFORE...MAY NEED TO INCLUDE A SLIGHT CHANCE OF AFT SHOWERS AND
TSTMS ACROSS THE NORTH FOR TODAY AS WELL. WILL LEAN TOWARD ISC AND
CURRENT GRIDS FOR A FINAL DECISION.
FOR THE NEAR TERM TEMPS...ABOVE NORMAL TEMPS EXPECTED WITH HIGHS
GENERALLY IN THE LOWER 90S...LOWS LOWER 70S...COOLER PLATEAU.
IN THE EXT FCST...SHORTWAVE TO DEVELOP OVER THE NATIONS INTERIOR
THIS WEEKEND. WIND FLOW PATTERN WILL THEN EVOLVE INTO A MORE UNIFORM
SOUTHERLY FLOW WHICH WILL BRING INCREASING MOISTURE LEVELS BACK
ACROSS THE AREA. THOUGH THE SHORTWAVE WILL LIFT OFF TO THE NE AND
NOT DIRECTLY IMPACT THE MID STATE...CONVECTIVE CONDITIONS WILL
BECOME MORE FAVORABLE. THE GFS ACTUALLY EMPHASIZES AN UPSTREAM
IMPULSE IN CLOSE PROXIMITY FOR SAT NT. SO...ALL IN ALL... POPS
WILL BE ON THE INCREASE FOR THE SAT THROUGH MON PERIOD.
THEREAFTER...W-E UPPER RIDGING WILL REDEVELOP ACROSS THE DEEP
SOUTH WITH POPS ON THE DOWNSWING.
FOR THE EXT TEMPS...ABOVE NORMAL VALUES TO CONTINUE EVEN THOUGH
RIDGING BACKS OFF DURING THE SAT THROUGH MON PERIOD. HEIGHTS
REMAIN ON THE ELEVATED SIDE.
21
&&
.OHX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
55
AREA FORECAST DISCUSSION...UPDATED
NWS FORT WORTH TX
1041 AM CDT WED AUG 27 2014
.UPDATE...
TODAY WILL BE A WARM DAY WITH ISOLATED SHOWERS AND THUNDERSTORMS
ACROSS THE REGION THROUGH THE EARLY EVENING HOURS. TEMPERATURES
TODAY WILL BE VERY SIMILAR TO YESTERDAYS HIGH TEMPERATURES. THE
12Z FWD SOUNDING THIS MORNING MEASURED A PWAT OF 1.66
INCHES...INDICATIVE OF DECENT MOISTURE ACROSS THE REGION.
HOWEVER...UNDER THE INFLUENCE OF EASTERLY FLOW FROM THE SURFACE TO
MID LEVELS OF THE ATMOSPHERE...BOTH THE NAM AND RAP INDICATE DRIER
AIR WILL MOVE INTO THE REGION THIS AFTERNOON FROM THE EAST. THIS
TREND IS SUPPORTIVE BY THE GOES PW SOUNDER WHICH INDICATES DRIER
AIR IS CURRENTLY TO OUR EAST. THE NAM AND RAP INDICATE THE DRIEST
AIR...WITH PWATS CLOSER TO 1-1.25 INCHES...WILL MOVE ACROSS OUR
SOUTHEAST COUNTIES THIS AFTERNOON AND CONTINUE A WESTWARD TRACK
THIS EVENING AND TONIGHT.
WHILE DRIER AIR MAY ARRIVE IN OUR EASTERN AND SOUTHEASTERN
COUNTIES LATER TODAY...THE REST OF THE REGION WILL REMAIN MOIST
AND HUMID. SINCE THE RIDGE HAS BEEN WEAKENED...EXPECT ISOLATED
CONVECTION TO OCCUR TODAY AND HAVE EXPANDED THE MENTION OF
ISOLATED SHOWERS/STORMS ACROSS ALL OF NORTH AND CENTRAL TEXAS. IT
WILL BE MORE DIFFICULT FOR CONVECTION TO DEVELOP IN OUR SOUTHEAST
ZONES WHEN THE DRIER AIR ARRIVES LATER BUT UNTIL THEN THERE IS
STILL A CHANCE FOR ISOLATED ACTIVITY. GUSTY WINDS AND BRIEF HEAVY
RAINFALL WILL OCCUR WITH ANY CONVECTION THIS AFTERNOON.
82/JLD
&&
.AVIATION...
/ISSUED 603 AM CDT WED AUG 27 2014/
VFR WILL PREVAIL WITH JUST SOME FAIR WX CUMULUS. LIGHT SOUTHEAST
WINDS WILL BECOME EASTERLY BY MIDDAY WITH SPEEDS NEAR 10KT. WINDS
WILL DIMINISH AND BECOME MORE SOUTHERLY TONIGHT.
&&
.PREV DISCUSSION... /ISSUED 324 AM CDT WED AUG 27 2014/
A WEAK TUTT WAS LOCATED JUST EAST OF CORPUS CHRISTI THIS MORNING
AND HAS RESULTED IN AN INCREASE IN PWATS AND INSTABILITY ACROSS
THE REGION. ISOLATED SHOWERS/THUNDERSTORMS ARE POSSIBLE OVER THE
WESTERN AND SOUTHERN COUNTIES THIS AFTERNOON AND EVENING.
UPSTREAM...UPPER TROUGH OVER THE GREAT BASIN WILL MOVE OUT OF THE
CENTRAL ROCKIES ON THURSDAY NIGHT AND ACROSS THE GREAT PLAINS BY
LATE FRIDAY NIGHT. SHORT WAVE FORCING FOR CONVECTION WILL BE BEST
ACROSS AREAS TO THE NORTH BUT IT WILL BE ADEQUATE FOR SCATTERED
SHOWERS/THUNDERSTORMS ACROSS NORTH AND CENTRAL TEXAS AS THE
SOUTHERN END OF THE TROUGH MOVES ACROSS THE REGION. WE WILL START
OUT WITH LOW CHANCE POPS THURSDAY AFTERNOON/EVENING...THEN
INCREASE POPS WEST TO EAST ON FRIDAY AS THE UPPER TROUGH NEARS.
ALTHOUGH SHEAR WILL BE LOW ON FRIDAY...CAPE WILL BE ADEQUATE FOR
SOME STRONG STORMS WITH GUSTY WINDS...AND LOCALLY HEAVY RAINFALL
DUE TO PWATS NEAR 2 INCHES. AS THE UPPER TROUGH MOVES INTO THE
MIDWEST AND EAST TEXAS OVER THE WEEKEND...WE WILL BE TRIMMING POPS
WEST TO EAST TO MATCH ITS POSITION. BY SUNDAY...POPS WILL BE
LIMITED TO 20S OVER THE FAR EASTERN COUNTIES. DRY WEATHER WILL
SETTLE IN FOR SUNDAY NIGHT THROUGH TUESDAY.
TEMPERATURES WILL BE RESPONDING TO SLIGHTLY LOWER HEIGHTS ALOFT DUE
TO THE TUTT AND THE PASSAGE OF THE UPPER TROUGH LATER IN THE
WEEK. HIGHS ON THURSDAY WILL WILL BE A DEGREE OR TWO COOLER THAN
THOSE EXPECTED TODAY...AND ABOUT 5 DEGREES COOLER ON FRIDAY DUE
TO ADDITIONAL CLOUDS AND SCATTERED CONVECTION. EXPECTING HIGHS TO
CREEP UP A FEW DEGREES ON SUNDAY WITH GENERALLY MID 90S THE FIRST
OF NEXT WEEK. LOW TEMPS WILL NOT CHANGE MUCH....BUT FRIDAYS
CONVECTION COULD RESULT IN SOME LOWER 70S OUT WEST AND ALONG THE
RED RIVER ON SATURDAY MORNING.
LOOKING AHEAD...HIGH PRESSURE ALOFT WILL BE BUILDING BACK OVER
THE REGION THE FIRST WEEK OF SEPTEMBER WITH THE WESTERLIES
REMAINING OVER THE NORTHERN PART OF THE COUNTRY. AS A
RESULT...THERE DOES NOT SEEM TO BE ANOTHER OPPORTUNITY FOR COOLER
WEATHER OR RAIN/STORMS UNTIL AFTER THE 10TH OF SEPTEMBER. 75
&&
.PRELIMINARY POINT TEMPS/POPS...
DALLAS-FT. WORTH, TX 98 77 97 78 93 / 10 10 10 20 50
WACO, TX 99 74 97 76 93 / 10 10 20 10 40
PARIS, TX 94 71 95 73 92 / 10 10 10 20 50
DENTON, TX 96 74 96 76 92 / 10 10 10 20 50
MCKINNEY, TX 96 72 96 75 92 / 10 10 10 20 50
DALLAS, TX 98 77 97 78 92 / 10 10 10 20 50
TERRELL, TX 97 75 96 75 93 / 10 10 10 20 50
CORSICANA, TX 96 76 97 75 93 / 10 10 10 10 40
TEMPLE, TX 98 73 96 75 93 / 10 10 20 20 50
MINERAL WELLS, TX 99 72 98 74 93 / 10 10 10 20 50
&&
.FWD WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
05/82
AREA FORECAST DISCUSSION
NWS PHOENIX AZ
910 AM MST WED AUG 27 2014
.SYNOPSIS...
DRIER AIR WILL CONTINUE TO MOVE INTO THE REGION TODAY...USHERING IN
A DRIER AND WARMER PATTERN ACROSS THE DESERT SOUTHWEST THROUGH AT
LEAST EARLY NEXT WEEK. HIGH TEMPERATURES WILL RETURN TO NEAR NORMAL
VALUES BY THURSDAY...PEAKING BETWEEN 105 AND 110 FRIDAY AND
SATURDAY...BEFORE RETREATING SLIGHTLY NEXT WEEK.
&&
.DISCUSSION...
TAIL END OF A SHORTWAVE TROUGH IS MOVING THROUGH GILA COUNTY THIS
MORNING...WITH A FEW LINGERING SHOWERS AND ISOLATED THUNDERSTORMS
NOTED ON SATELLITE AND RADAR. WV IMAGERY REVEALS THE PARENT
CIRCULATION ACROSS EASTERN UTAH WITH SUBSTANTIAL MID LEVEL DRYING
STRETCHING FROM SOUTH-CENTRAL ARIZONA WESTWARD INTO CENTRAL
CALIFORNIA. SURFACE DEWPOINTS HAVE BEEN SLOW TO RESPOND AND ARE
GENERALLY IN THE LOW TO MID 60S AS OF 16Z.
STRONG SUBSIDENCE AND MID LEVEL WARM ADVECTION HAS ALREADY COMMENCED
ACROSS SOUTHEAST CALIFORNIA AND SOUTHWEST ARIZONA AND WILL CONTINUE
TO SPREAD WESTWARD THIS AFTERNOON. THE HRRR ALONG WITH SEVERAL OTHER
LOCAL HI-RES MODELS INDICATE A FEW POP-UP SHOWERS ARE POSSIBLE WELL
EAST OF PHOENIX THIS AFTERNOON...BUT THE DESERTS WILL REMAIN DRY.
THE INHERITED FORECAST INDICATED 10-20 POPS FOR THIS AFTERNOON BUT
BASED ON HOW QUICKLY THE SHORTWAVE IS EXITING THE AREA...I MADE
SLIGHT REDUCTIONS TO POPS FOR LATER TODAY. ALL IN ALL IT SHOULD BE A
QUIET DAY...NO MAJOR UPDATES NECESSARY.
&&
.PREVIOUS DISCUSSION...
FOR THURSDAY THROUGH THE WEEKEND...ZERO POPS ARE IN THE FORECAST
DURING THE PERIOD AS A VERY DRY NORTHWESTERLY UPPER LEVEL FLOW
PATTERN PERSISTS ACROSS THE DESERT SOUTHWEST. THE SUBTROPICAL HIGH
BUILDS WESTWARD BEHIND THE EXITING PACIFIC LOW WITH THE HIGH CENTER
SETTLING JUST OFF THE SOUTHERN CALIFORNIA COAST. THIS WILL ALLOW
500MB HEIGHTS TO BUILD ACROSS OUR REGION AND FOR AN UPTICK IN
TEMPERATURES. HIGHS WILL RETURN TO NEAR SEASONAL NORMALS ALREADY ON
THURSDAY AND THEN CLIMB A COUPLE DEGREES HIGHER FOR FRIDAY AND
SATURDAY. WOULDN/T BE SURPRISED IF A FEW LOCATIONS ACROSS THE
SOUTHEAST CALIFORNIA AND SOUTHWEST ARIZONA DESERTS HIT 110 ON FRIDAY
AND SATURDAY.
THE UPPER RIDGE WILL BEGIN TO BREAK DOWN ON SATURDAY AS A TROUGH
MOVES INTO THE PACIFIC NORTHWEST. MODELS ARE IN EXCELLENT AGREEMENT
THIS TROUGH WILL FLATTEN THE RIDGE TO OUR SOUTHWEST...BUT KEEP US
UNDER A WESTERLY TO NORTHWESTERLY DRY UPPER LEVEL FLOW INTO NEXT
MONDAY. HIGHS SHOULD START TO TREND DOWNWARD STARTING SUNDAY AS THE
TROUGH TO OUR NORTH SLOWLY KNOCKS DOWN OUR UPPER HEIGHTS. SOME MODEL
DIFFERENCES ARE SHOWN NEAR THE END OF THE FORECAST PERIOD FOR NEXT
TUESDAY AND WEDNESDAY AS THE EUROPEAN BEGINS TO REBUILD THE
SUBTROPICAL HIGH TO OUR SOUTHEAST AND POSSIBLY ALLOWS FOR SOME
MINIMAL MOISTURE RETURN UNDER WEAK SOUTHEASTERLY FLOW. THE GFS KEEPS
THE DRIER WESTERLY FLOW ALOFT UNDER A WEAKER SUB-TROPICAL HIGH
CENTERED STILL TO OUR SOUTHWEST. TO ACCOUNT FOR THE POTENTIAL RETURN
IN MONSOONAL MOISTURE...HAVE INTRODUCED AT LEAST SOME LOW END SLIGHT
CHANCE POPS FOR TUESDAY AND WEDNESDAY ACROSS THE HIGHER TERRAIN IN
GILA COUNTY.
&&
.AVIATION...
SOUTH-CENTRAL ARIZONA INCLUDING KPHX...KIWA...AND KSDL...AND
SOUTHWEST ARIZONA AND SOUTHEAST CALIFORNIA INCLUDING KIPL AND KBLH...
GIVEN THE STRONG SUBSIDENCE FORECAST TO MOVE INTO THE AREA
TODAY...WEATHER CONCERNS ARE MINIMAL THROUGH THURSDAY. MOSTLY CLEAR
SKIES AND LIGHT DIURNAL WINDS ARE FORECAST AT ALL SITES.
AVIATION DISCUSSION NOT UPDATED FOR AMENDED TAFS.
&&
.FIRE WEATHER...
FRIDAY THROUGH TUESDAY...
STRONG HIGH PRESSURE ALOFT AND DRY NORTHWEST FLOW WILL BUILD OVER
THE DISTRICT THROUGH EARLY NEXT WEEK. EVEN ACROSS GILA
COUNTY...CHANCES FOR THUNDERSTORMS ARE ALMOST ZERO THROUGH THE
ENTIRE PERIOD. WITH TEMPERATURES AT OR SLIGHTLY ABOVE THE SEASONAL
AVERAGE...AFTERNOON HUMIDITIES WILL RANGE FROM THE TEENS AT LOWER
ELEVATIONS TO 20-30 PERCENT OVER HIGHER TERRAIN. FAIR OVERNIGHT
RECOVERY THROUGH THE WEEKEND WILL GRADUALLY INCREASE...BECOMING GOOD
OR EXCELLENT BY EARLY NEXT WEEK. WIND SPEEDS WILL BE UNCOMMONLY LOW
THROUGH THE WEEKEND...WITH VERY LITTLE GUSTY CHARACTER.
&&
.PSR WATCHES/WARNINGS/ADVISORIES...
AZ...NONE.
CA...NONE.
&&
$$
VISIT US ON FACEBOOK...TWITTER...AND AT WEATHER.GOV/PHOENIX
DISCUSSION...LEINS/KUHLMAN
AVIATION...LEINS
FIRE WEATHER...CB/MO
AREA FORECAST DISCUSSION
NWS PUEBLO CO
311 PM MDT WED AUG 27 2014
.SHORT TERM...(THIS EVENING THROUGH THURSDAY)
ISSUED AT 240 PM MDT WED AUG 27 2014
...FEW STRONG STORMS POSSIBLE LATER TODAY AND THIS EVENING...SOME
SNOW AT THE HIGHEST PEAKS...
CURRENTLY...
VERY WELL DEFINED UPPER LOW AS SEEN BY WATER VAPOR IMGY WAS SPINNING
OVER NE UTAH. A VORT LOBE FROM THIS SYSTEM WAS OVER WESTERN COLORADO
AS A LINE OF TSRA WAS ADVANCING EAST OVER THIS REGION. OVER THE NWS
PUB CWA...A DRY SLOT ASSOCIATED WITH THIS UPPER LVL LOW WAS OVER THE
WESTERN 1/2 OF THE PLAINS...AS SKIES WERE GENERALLY SUNNY. TEMPS
OVER THE PLAINS HAVE WARMED UP INTO THE 80S GENERALLY BELOW 5500
FEET...WITH 60S AND 70S MOST OTHER LOCATIONS. LOOKING AT THE
THERMODYNAMIC FIELDS...CAPE VALUES FROM THE SPC WERE IN THE 1000
RANGE WHILE FARTHER EAST VALUES WERE 2500 J/KG. EFFECTIVE DEEP SHEAR
WAS 30-35 KNTS.
AT THE SFC ACROSS THE REGION...A WEEK COOL FRONT WAS CLEARLY SEEN IN
THE VIS SAT PIX IMGY ALONG THE EL PASO/DOUGLAS/ELBERT COUNTY LINE
AND IT WAS PROGRESSING SLOWLY SWD.
REST OF THIS AFTERNOON AND EVENING...
VORT LOBE OVER W CO WILL LIKELY START AFFECTING THE GREATER PIKES
PEAK REGION LATE THIS AFTERNOON AND INTO THIS EVENING. HRRR REALLY
DOES NOT GET THINGS GOING UNTIL AFTER 9 PM...AND I BELIEVE THIS IS
TOO LATE AS THINGS WILL LIKELY GET GOING BY VERY LATE AFTERNOON OR
EARLY EVENING. AS MENTIONED ABOVE...SHEAR AND CAPE ARE INCREASING
AND I DO EXPECT WE WILL SEE A FEW SUPERCELLS OVER THE EASTERN PLAINS
OF COLORADO. SPC RECENTLY ISSUED AN MCD DISCUSSING THIS THREAT.
WALDO WILL ALSO NEED TO BE WATCHED. ALTHOUGH STORMS WILL MOVE AT A
GOOD CLIP TODAY...ATMOSPHERE HAS PLENTY OF MOISTURE AND ANY HEAVY
RAIN OVER A SHORT PERIOD OF TIME WILL CAUSE ISSUES OVER THE BURN
SCARS.
OVERALL...I BELIEVE BEST CHANCE OF SEVERE WILL GENERALLY BE ALONG
AND NORTH OF HIGHWAY 50...ASSOCIATED WITH SOUTHWARD MOVING
BOUNDARY...ALTHOUGH STRONG STORMS COULD OCCUR ANYWHERE ACROSS THE
REGION GIVEN THE MOISTURE AND DYNAMIC FORCING ASSOCIATED WITH THE
UPPER LOW HEADING OUR WAY.
TONIGHT...
UPPER LOW WILL BE OVER THE STATE. ISOLATED SHOWERS ARE LIKELY TO
CONTINUE THROUGHOUT THE NIGHT...BUT AS MENTIONED...BELIEVE THEY WILL
BE ISOLATED. BEST CHANCE WILL BE OVER THE CONTDVD REGION. SNOW
SHOWERS WILL OCCUR AT HIGHER ELEVATIONS WITH SOME LIGHT ACCUMS
LIKELY.
TOMORROW...
COOL NORTHEAST LLVL FLOW WILL PREVAIL OVER REGION. WITH UPPER LOW
OVERHEAD...ANTICIPATE SKIES WILL CLOUD UP RELATIVELY EARLY. ALTHOUGH
QUITE A FEW SHOWERS WILL LIKELY DEVELOP TOMORROW...OVERALL HEAVY
RAIN THREAT LOOKS LOW AT THIS TIME. IT WILL BE NOTICEABLY COOLER
TOMORROW ACROSS THE REGION AS HIGHS WILL ONLY BE IN THE 70S ALONG THE
I-25 CORRIDOR WITH TEMPS AOA 80F OVER THE FAR E PLAINS. 60S AND
70S ELSEWHERE ACROSS THE VALLEYS. IT WILL BE COOL ABOVE TREELINE
WITH HIGHS ONLY IN THE 30S AND 40S. SNOWSHOWERS WILL BE POSSIBLE.
OVERALL BEST CHANCE OF SHOWERS TOMORROW WILL BE ALONG THE EAST
FACING SLOPES OF THE EASTERN MTNS. /HODANISH
.LONG TERM...(THURSDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 240 PM MDT WED AUG 27 2014
UPPER LOW FINALLY EXITS THE STATE EARLY FRI MORNING...WITH WEAK
CONVECTION ENDING FROM WEST TO EAST ACROSS THE REGION THU EVENING.
FLAT UPPER RIDGE THEN BUILDS ACROSS THE AREA FRI LEADING TO
MOSTLY DRY CONDITIONS AND SEASONABLY MILD TEMPS...ALTHOUGH SOME
ISOLATED WEAK TSRA MAY FORM OVER THE MTS IN THE AFTERNOON AS
RESIDUAL LOW LEVEL MOISTURE LINGERS. NEW WESTERN U.S. TROUGH
BEGINS TO MOVE ONSHORE DURING THE WEEKEND...WITH INCREASING W-SW
FLOW ACROSS COLORADO SAT INTO SUN. STILL A VERY SMALL CHANCE OF
SOME ISOLATED TSRA OVER THE HIGHER TERRAIN SAT AFTERNOON...THOUGH
AGAIN STORMS SHOULD BE HIGH BASED AND WEAK AS MOIST LAYER IS
FAIRLY SHALLOW. UPPER TROUGH THEN MOVES INTO THE NORTHERN HIGH
PLAINS SUN...PUSHING A COLD FRONT THROUGH COLORADO DURING THE
AFTERNOON. WITH NOSE OF THE UPPER JET MOVING ACROSS NORTHERN
COLORADO...STRONGEST UPWARD MOTION WILL LIKELY STAY NORTH OF THE
AREA...AND ONLY A SLIGHT CHANCE OF TSRA IS EXPECTED OVER THE
CENTRAL MTS AND FAR EASTERN PLAINS SUN AFTERNOON/EVENING. TEMPS
BOTH SAT AND SUN WILL CLIMB BACK ABOVE NORMAL...WITH WARMEST
READINGS JUST AHEAD OF THE COLD FRONT ON SUN.
WEAK LOW LEVEL MOISTURE RETURN DEVELOPS BEHIND THE FRONT ON
MON...THOUGH AIR MASS STAYS FAIRLY STABLE THROUGH THE DAY UNDER
SUBSIDENT UPPER FLOW BEHIND THE DEPARTING TROUGH. AS A
RESULT...SUSPECT ANY CONVECTION ON THE PLAINS WILL HAVE TO WAIT
FOR DEVELOPING WARM ADVECTIVE LIFT LATE MON NIGHT AS LOW LEVEL JET
DEVELOPS. ON TUE/WED...SHALLOW UPSLOPE FLOW WILL CONTINUE OVER THE
EASTERN MOUNTAINS AND PLAINS...THOUGH WITH FORCING STAYING RATHER
WEAK...SUSPECT CONVECTIVE COVERAGE WILL BE ONLY ISOLATED BOTH
DAYS. AFTER SOME MODEST COOLING ON MON...TEMPS BEGIN TO SLOWLY
CREEP BACK TO ABOVE SEASONAL LEVELS BY WED...ESPECIALLY OVER THE
PLAINS WERE A FEW 90S WILL REAPPEAR.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z THURSDAY AFTERNOON)
ISSUED AT 240 PM MDT WED AUG 27 2014
MAIN CONCERN IS CONVECTIVE ACTIVITY...ESPECIALLY AT KCOS LATE THIS
AFTERNOON AND EVENING. LOCALLY HEAVY RAIN AND POSSIBLY SOME SMALL
HAIL WILL BE POSSIBLE. LATER TONIGHT...MODELS HINTING AT SOME LOW
CIGS POSSIBLE NEAR DAYBREAK. CIGS WILL LIFT BY MID TO LATE MORNING
BUT CLOUDS MAY HANG AROUND A GOOD PART OF TOMORROW WITH PATCHY
ON AND OFF SHOWERS.
KPUB AND KALS WILL HAVE SOME ISOLD TSRA LATE THIS AFTERNOON AND
EVENING...OTHERWISE GENERALLY VFR.
&&
.PUB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...HODANISH
LONG TERM...PETERSEN
AVIATION...HODANISH
AREA FORECAST DISCUSSION
NWS TAUNTON MA
419 PM EDT WED AUG 27 2014
.SYNOPSIS...
A COLD FRONT APPROACHING THE REGION WILL TRIGGER A FEW SHOWERS AND
THUNDERSTORMS THIS EVENING AND OVERNIGHT. THE FRONT MOVES OFFSHORE
EARLY THU MORNING WITH DRIER AND LESS HUMID AIR OVERSPREADING
SOUTHERN NEW ENGLAND THU AND FRI...YIELDING MILD DAYS AND COOL
NIGHTS. HURRICANE CRISTOBAL WILL PASS WELL OFFSHORE LATE TONIGHT
INTO THURSDAY...BUT WILL BRING DANGEROUS SURF AND RIP CURRENTS TO
SOUTH FACING OCEAN BEACHES OF RI AND MA. PLEASANT WEATHER LINGERS
INTO SAT...THEN A FRONT MAY STALL ACROSS NEW ENGLAND SUN INTO MON
BRINGING UNSETTLED CONDITIONS.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
4 PM UPDATE...
LATEST RUNS OF NAM...12Z ECMWF ALONG WITH HRRR AND RAP13 HAVE BEEN
TRENDING TOWARD LESS CONVECTIVE QPF THIS EVENING AND OVERNIGHT.
DESPITE MODEST INSTABILITY BEING OBSERVED ON SPC MESOANALYSIS OF
1000-1500 J/KG FROM CENTRAL MA WESTWARD INTO EASTERN NY...THE LACK
OF SHEAR AND SURFACE CONVERGENCE IS KEEPING CONVECTION ISOLATED TO
WIDELY SCATTERED SO FAR. GIVEN THE ARRIVAL OF THE MID LEVEL TROUGH
AND ASSOCIATED DEEP LAYER SHEAR IS AFTER PEAK HEATING /00Z-
06Z/...NOT EXPECTING MUCH IF ANY SEVERE STORMS. HOWEVER CAN/T
COMPLETELY RULE OUT AN ISOLATED STRONG STORM OVER WESTERN CT/MA
WITH GUSTY WINDS GIVEN INVERTED / SOUNDING SIGNATURE AND BRIEF
HEAVY RAIN WITH PWATS UP TO 1.7 INCHES OVER THE LOWER HUDSON
VALLEY. CONVECTION WILL WEAKEN AFTER 00Z GIVEN BOUNDARY LAYER
COOLING AND WEAK MID LEVEL LAPSE RATES. HOWEVER MODEST SYNOPTIC
SCALE FORCING FOR ASCENT AND INCREASING DEEP LAYER SHEAR MAY BE
SUFFICIENT FOR A BROKEN LINE OF SHOWERS TO TRAVERSE TO THE COAST
LATER THIS EVENING.
GIVEN THE LATER TROUGH ARRIVAL COLD FRONTAL PASSAGE NOT EXPECTED
TO CLEAR OUR REGION UNTIL OVERNIGHT AND PROBABLY NOT UNTIL SUNRISE
FOR THE SOUTH COAST INCLUDING CAPE COD AND THE ISLANDS. THUS
ANOTHER WARM NIGHT.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 AM FRIDAY/...
THURSDAY...
POST FRONTAL AIRMASS OVERSPREADS THE REGION AS COLD FRONT DEPARTS
THE SOUTH COAST DURING THE EARLY MORNING. MID LEVEL FLOW REMAINS
CYCLONIC AS MEAN TROUGH AXIS ALOFT REMAINS OVER NEW ENGLAND.
HOWEVER STRONG DRYING THROUGH THE COLUMN WITH NEGATIVE K-INDICES
OVERSPREADING THE REGION ALONG WITH DEW PTS TUMBLING INTO THE 50S
AND POSSIBLY THE U40S. HOWEVER GIVEN THE COOL TEMPS ALOFT AND
CYCLONIC FLOW SHOULD SEE SCT-BKN CU/SCU DURING THE PEAK HEATING
HOURS OF THE AFTERNOON.
NEVERTHELESS A SPECTULAR DAY WITH LOW HUMIDITY...A REFRESHING NW
BREEZE OF 10 TO 20 MPH AND TEMPS NOTICEABLY COOLER WITH HIGHS 75
TO 80.
HIGH SURF....
HURRICANE CRISTOBAL PASSES WELL OFFSHORE BUT WNA AND THE HURRICANE
VERSION OF THE WNA YIELDS 5-10 FT SWELLS ENTERING THE NEAR SHORE
WATERS AND UP TO 12 FT WELL SOUTH OF MVY AND ACK. OUR IN HOUSE
SURF CALCULATION SUGGEST BREAKERS OF 6-12 FT AT SOUTH FACING OCEAN
BEACHES TOMORROW. THUS VERY DANGEROUS SURF AND RIP CURRENTS.
OBVIOUSLY WILL CONTINUE THE HIGH SURFACE ADVISORY WHICH MAY HAVE
TO BE EXTENDED INTO FRI AS THE WAVE MODELS TYPICALLY ERODE SWELL
ENERGY TOO QUICKLY. SURF AND RIP CURRENTS WILL NOT BE AS DANGEROUS
ALONG THE EASTERN MA COAST AS THE SWELL ENERGY WILL BE PARALLEL TO
THIS COASTLINE.
THU NIGHT...
CORE OF COOL AIRMASS MOVES OVER THE REGION WITH 850 MB AND 925 MB
TEMPS ABOUT +1 SD COOLER THAN NORMAL. N-NE WINDS WILL PRECLUDE
EASTERN MA FROM COOLING OFF TOO /L60S/ MUCH GIVEN OCEAN WIND
TRAJECTORY. HOWEVER INTERIOR VALLEYS THAT DECOUPLE COULD SEE MINS
IN THE MU40S WITH 50S ELSEWHERE.
&&
.LONG TERM /FRIDAY THROUGH WEDNESDAY/...
*/ HIGHLIGHTS...
- SEASONABLE AND DRY WEATHER FOR FRIDAY...ENJOY IT!
- HOT AND HUMID CONDITIONS THROUGH THE WEEKEND
- THUNDERSTORMS POSSIBLE ACROSS N/W NEW ENGLAND SUNDAY
- WET WEATHER ANTICIPATED SUNDAY NIGHT INTO MONDAY NIGHT
- COULD REMAIN WARMER THAN AVERAGE INTO NEXT WEEK
*/ OVERVIEW AND MODEL PREFERENCE...
BETTER AGREEMENT AMONG ENSEMBLE MEMBERS WOULD SUGGEST A ZONAL FLOW
REGIME WITH SOME WEAK RIDGING AS BOTH THE NAO/PNA REMAIN NEGATIVE TO
NEAR-NEUTRAL. EXPECTING AN ABOVE AVERAGE TEMPERATURE PATTERN AS THE
ECENS/GEFS/NAEFS/CPC WOULD SUGGEST INTO EARLY SEPTEMBER...ANOMALOUS
ON THE ORDER OF +2-3 STANDARD DEVIATIONS. WITH ANTICIPATED WARMER
CONDITIONS SUBSEQUENT OF RIDGING...EXPECTING PROLONGED S-FLOW TO
ADVECT MUGGY CONDITIONS N. LOOKING TO BE A WARM AND HUMID TIMEFRAME.
FOR THE FORECAST PERIOD OVER THE NEXT WEEK BEGINNING FRIDAY...EXPECT
THE W-ATLANTIC RIDGE TO BE THE DOMINANT INFLUENCE OVER THE REGIONS
WEATHER. FAVOR THE ECMWF WITH THE CONFLUENT FLOW SETUP AND ATTENDANT
SURFACE FRONTAL POSITION BETWEEN THE NE-CANADA TROUGH AND W-ATLANTIC
RIDGE REMAINING N OF THE REGION PARENT WITH BETTER JET-DYNAMICS AND
SHEARED MID-LEVEL ENERGY. ONLY AS A C-CONUS DISTURBANCE INVOKES A
WEAK-WAVE LOW ALONG THE FRONT WILL WET-WEATHER SHIFT INTO OUR AREA
AROUND MONDAY BASED ON A CONSENSUS OF MODEL DATA.
DESPITE MODEL VARIANCE...A BROAD SIGNAL IS DISCERNABLE OF A BRIEF
PERIOD OF DRY WEATHER AFTER PASSAGE OF THE WEAK-WAVE LOW...FOLLOWED
BY A SHARP COLD FRONT AND PERHAPS THE RETURN OF MORE SEASONABLE
CONDITIONS. LOW CONFIDENCE AT THIS TIME AS ENSEMBLE MEANS WOULD
SUGGEST THE PROPENSITY FOR ZONAL-FLOW WITH WEAK RIDGING. FAVOR THE
DETERMINISTIC ECMWF WITH POSSIBLE OUTCOMES.
HIGHLIGHTS/CONFIDENCE ARE BROKEN DOWN IN THE DAILY DISCUSSION BELOW.
*/ DAY-TO-DAY DETAILS...
FRIDAY...
HIGH PRESSURE. LIGHT/VARIABLE WINDS. SEA-BREEZES ALONG THE COASTS.
SEASONABLE AND MOSTLY CLEAR CONDITIONS...SLIGHTLY COOLER ALONG THE
SHORES...WITH HIGHS AROUND THE MID-70S. MID- TO HIGH-LEVEL CLOUDS
POSSIBLE AHEAD OF AN ENCROACHING WARM-FRONT FROM THE SW. ALONG WITH
WINDS TURNING S OVERNIGHT AS HIGH PRESSURE SHIFTS E...EXPECT MILDER
CONDITIONS WITH LOWS AROUND THE MID-50S.
SATURDAY...
SURFACE WARM FRONT LIFTING NE ACROSS NEW ENGLAND LATE...JOINING WITH
A TRAILING COLD FRONT FROM A LOW DISTURBANCE OVER NE-CANADA. AS THE
RIDGE SUBSEQUENTLY ENHANCES AHEAD OF THE FRONTAL DISTURBANCE AND A
WEAKER DISTURBANCE OVER THE C-CONUS...BELIEVE WET-WEATHER ACTIVITY
WILL BE PUSHED WELL N OF THE REGION BY THE INFLUENCE OF THE RIDGE.
THUS WILL GO WITH A DRY-WEATHER FORECAST.
EXPECT PREVAILING S-FLOW TO BEGIN USHERING WARMER / HUMID CONDITIONS
ACROSS THE REGION. WILL SEE HIGHS WARM INTO THE LOW-80S AS A WELL-
MIXED BOUNDARY LAYER ALLOWS FOR SCATTERED CUMULUS ALONG WITH THE MIX-
DOWN OF BREEZY S/SW FLOW. FEEL THIS WILL RESTRICT SEA-BREEZES...SO
EXPECT INTERIOR WINDS TO PUSH THE WARM / HUMID CONDITIONS ALL THE
WAY TO THE E-SHORES.
MILD AND DRY OVERNIGHT. WITH A LINGERING DRY-SUBSIDENCE INVERSION...
HIGHER DEWPOINT AIR ADVECTING N COULD LEND TO LOW CLOUDS / FOG ALONG
THE S-SHORE. EXPECTING LOWS AROUND THE LOW- TO MID-60S.
SUNDAY...
WARM-FRONT WELL-DEFINED TO THE N. PUSH OF H85 +16-18C AIR ACROSS THE
REGION. EXPECT S NEW ENGLAND TO BE WITHIN THE WARM-SECTOR OF A HOT
AND HUMID AIRMASS. COLLOCATED WITHIN A WELL-MIXED BOUNDARY LAYER...
BREEZY S/SW-FLOW DURING THE DAY SHOULD ALLOW FOR INTERIOR WINDS ONCE
AGAIN TO RESTRICT SEA-BREEZES AND PUSH FORECAST HIGH TEMPERATURES
AROUND THE UPPER-80S TO THE E-SHORES.
HEIGHTS FALL AS THE C-CONUS DISTURBANCE SHIFTS E WITHIN THE QUASI-
ZONAL FLOW REGIME. SHOWERS / THUNDERSTORMS ARE CERTAINLY PLAUSIBLE N
AND W WITHIN MODEST INSTABILITY AND SHEAR...CLOSER TO REGIONS OF
FAVORABLE DYNAMICS / ASCENT AS WELL AS THE CONVERGENT NOSE OF HIGHER
THETA-E AIR AHEAD OF THE FRONT. LIKELY THE MAJORITY OF ACTIVITY IS
ACROSS THE E GREAT LAKES INTO NY/PA...BUT ITS POSSIBLE THAT ACTIVITY
DEVELOPS INTO N/W NEW ENGLAND LATE. THIS WOULD POSSIBLY BE THE CASE
AS THE CONVECTIVE TEMPERATURE IS MET SUCH THAT ANY INVERSION WOULD
ERODE AND BOTH SURFACE-BASED INSTABILITY AND EFFECTIVE SHEAR COULD
BE UTILIZED. CAN NOT RULE OUT STRONG STORMS...ESPECIALLY ACROSS S/W
FACING SLOPES OF HIGH TERRAIN OVER NW CT / W MA / S NH AS OROGRAPHIC
PROCESSES AID IN LIFTING THE WARM / JUICY AIRMASS ALOFT. BUT IT IS
POSSIBLE THAT THE RIDGE WINS OUT. STILL A FORECAST WAY OUT IN TIME
AND AS WE HAVE SEEN JUST IN THE PAST SEVERAL MODEL RUNS THERE HAS
BEEN A FAIR AMOUNT OF VARIABILITY. HAVE MODERATE CONFIDENCE WITH
THIS FORECAST TIMEFRAME.
RIDGE AND SUBSIDENCE INVERSION LINGERS FOR THE S/E SO WILL KEEP WITH
A DRY-FROECAST FOR THOSE AREAS.
SUNDAY NIGHT THROUGH MONDAY NIGHT...
WEAK-WAVE LOW ALONG THE FRONT THROUGH THE QUASI-ZONAL FLOW PUSHES E
AND ACROSS THE REGION. THOUGH APPEARING AS A NOCTURNAL PASSAGE...THE
COLLOCATION OF DEEP-LAYER MOISTURE...MINOR INSTABILITY AND SHEAR...
AND FORCING ALONG THE FRONTAL BOUNDARY WILL LIKELY YIELD WIDESPREAD
SHOWERS WITH THE POSSIBILITY OF HEAVY RAIN AND THUNDERSTORMS. THOUGH
IT APPEARS THE BETTER FORCING DYNAMICS SHIFT N/E...SHUNTED BY THE
RIDGING PATTERN AND BERMUDA HIGH REMAINING DOMINANT.
LOW CONFIDENCE FORECAST AS THE CONSENSUS OF MODEL SOLUTIONS CONTAINS
A FAIR AMOUNT OF VARIABILITY. WILL PREVAIL WITH SLIGHTLY ABOVE-
AVERAGE CONDITIONS.
TUESDAY ONWARD...
A LULL IN ACTIVITY IS POSSIBLE BEHIND THE WEAK-WAVE DISTURBANCE. A
SHARPER COLD FRONT INTO MIDWEEK FOLLOWED BY HIGH PRESSURE. NOT ALL
ENTIRELY CONVINCED ON SUCH OUTCOMES BASED ON ENSEMBLE TRENDS. WOULD
ANTICIPATE RIDGING TO REMAIN DOMINANT WITH TEMPERATURES BEING ABOVE-
AVERAGE FOR THE TIMEFRAME.
&&
.AVIATION /20Z WEDNESDAY THROUGH MONDAY/...
FORECASTER CONFIDENCE LEVELS...
LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.
SHORT-TERM /TODAY THROUGH THURSDAY/...MODERATE CONFIDENCE.
THRU 00Z...ANY -TSRA NOT FIRING UNTIL 20Z/21Z WESTERN NEW ENGLAND
WITH CHANCES FARTHER EAST FADING TOWARD 00Z. ACTIVITY WILL BE
ISOLATED OR WIDELY SCATTERED. VFR PREVAILS WITH LOW RISK OF BRIEF
MVFR IN -TSRA.
AFTER 00Z...ISOLATED TO WIDELY SCATTERED SHOWERS TIL 06Z THEN
MOVING OFFSHORE WITH FRONTAL PASSAGE AND WIND SHIFT FROM SW TO NW
06Z-12Z FROM NW TO SE. VFR PREVAILS WITH BRIEF MVFR POSSIBLE IN
ANY HEAVIER SHOWERS. LOW RISK OF BRIEF IFR SOUTH COAST UNTIL
FRONTAL PASSAGE 06Z-12Z.
THURSDAY...VFR. NORTHWEST WINDS MAY GUST TO 20 KNOTS WITH
SCATTERED TO BROKEN SKY COVER AROUND 5000 FEET FROM MIDDAY TO
EVENING.
THU NIGHT...VFR AND DRY WITH A MODEST NW WIND 10-20 KT DIMINISHING
TOWARD MORNING.
KBOS TERMINAL...HIGH CONFIDENCE IN TAF. ISOLATED -SHRA/-TSRA 22Z-
04Z POSSIBLE. GIVEN LIMITED AREAL COVERAGE DECIDED NOT TO INCLUDE
VCTS AND JUST GO WITH VCSH...THE HIGHER PROBABILITY.
KBDL TERMINAL...HIGH CONFIDENCE IN TAF. ISOLATED -SHRA/-TSRA
21Z-03Z. GIVEN LIMITED AREAL COVERAGE DECIDED NOT TO INCLUDE
VCTS AND JUST GO WITH VCSH...THE HIGHER PROBABILITY.
OUTLOOK...FRI THROUGH MONDAY...
FRIDAY...HIGH CONFIDENCE.
VFR. LIGHT WINDS. SEA-BREEZES ALONG THE SHORES. SKC.
SATURDAY INTO SUNDAY...MODERATE CONFIDENCE.
VFR. BREEZY S/SW WINDS. SCT CIGS 4-6 KFT SATURDAY. MVFR-IFR CIGS /
VSBYS POSSIBLE ALONG THE S-COAST SATURDAY NIGHT. SHRA/TSRA POSSIBLE
FOR N/W NEW ENGLAND LATE SUNDAY.
SUNDAY NIGHT INTO MONDAY...LOW CONFIDENCE.
MIX OF LOW-END VFR TO MVFR. WIDESPREAD SHRA ACROSS THE TERMINALS.
POSSIBLE TSRA. CONTINUED S/SW WINDS.
&&
.MARINE...
FORECASTER CONFIDENCE LEVELS...
LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.
SHORT-TERM /TONIGHT THROUGH THURSDAY/...HIGH CONFIDENCE.
TONIGHT...
SOUTH SWELLS FROM CRISTOBAL CONTINUE TO INCREASE. A FEW SHOWERS
POSSIBLE THIS EVENING AND OVERNIGHT. SSW WINDS BECOME NW TOWARD
SUNRISE AS COLD FRONT APPROACHES FROM THE WEST.
THU...
SWELLS PEAK AT 5 TO 11 FT TOMORROW ACROSS THE SOUTH COAST WATERS.
ADDING TO THE ROUGH SEAS WILL BE A DEVELOPING NW WIND WAVE BEHIND
THE FRONTAL PASSAGE. OTHERWISE DRY WEATHER WITH GOOD VSBY. HOWEVER
A FEW SHOWERS MAY LINGER EARLY IN THE MORNIGN ACROSS THE SOUTH
COASTAL WATERS.
THU NIGHT...
NW WINDS BECOME N-NE LATE. GOOD VSBY AND DRY WEATHER.
OUTLOOK...FRIDAY THROUGH MONDAY...
FRIDAY...HIGH CONFIDENCE.
HIGH PRESSURE IN CONTROL. LIGHT WINDS. DIMINISHING SEAS WITH ONLY
THE S/SE OUTER WATERS EXPERIENCING WAVE HEIGHTS IN EXCESS OF 5-FEET
BY MORNING. GOOD BOATING WEATHER.
SATURDAY INTO SUNDAY...MODERATE CONFIDENCE.
INCREASING S-WINDS. PROLONGED S-FETCH LENDING TO WAVE HEIGHTS IN
EXCESS OF 5-FEET ACROSS THE S/SE WATERS. FOG POSSIBLE DURING THE
OVERNIGHT HOURS...ESPECIALLY ALONG THE S-COAST.
MONDAY...MODERATE CONFIDENCE.
CONTINUED S-WINDS. WET-WEATHER MOVING ACROSS THE WATERS. FOG MAY
REMAIN AN ISSUE OVER THE WATERS...ESPECIALLY DURING OVERNIGHT
PERIODS.
&&
.BOX WATCHES/WARNINGS/ADVISORIES...
CT...AIR QUALITY ALERT UNTIL 9 PM EDT THIS EVENING FOR CTZ002>004.
MA...HIGH SURF ADVISORY FROM 8 PM THIS EVENING TO 8 PM EDT THURSDAY
FOR MAZ020-022>024.
NH...NONE.
RI...HIGH SURF ADVISORY FROM 8 PM THIS EVENING TO 8 PM EDT THURSDAY
FOR RIZ006>008.
AIR QUALITY ALERT UNTIL 11 PM EDT THIS EVENING FOR RIZ001>005.
MARINE...SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS UNTIL 6 AM EDT FRIDAY
FOR ANZ235-237-254>256.
&&
$$
SYNOPSIS...NOCERA/SIPPRELL
NEAR TERM...NOCERA
SHORT TERM...NOCERA
LONG TERM...SIPPRELL
AVIATION...NOCERA/SIPPRELL
MARINE...NOCERA/SIPPRELL
AREA FORECAST DISCUSSION
NWS TAUNTON MA
215 PM EDT WED AUG 27 2014
.SYNOPSIS...
HIGH PRESSURE OFFSHORE WILL DRAW WARMER AIR ACROSS NEW ENGLAND
TODAY WITH HIGHS AROUND 90 FOR MANY LOCATIONS. A COLD FRONT WILL
THEN SWEEP THROUGH DURING THE LATE AFTERNOON AND EARLY
NIGHT...BRINGING WIDELY SCATTERED SHOWERS AND THUNDERSTORMS. DRY
AND COOLER CONDITIONS RETURN THURSDAY AND FRIDAY BEHIND THE FRONT.
HURRICANE CRISTOBAL WILL PASS WELL OFFSHORE LATE TONIGHT INTO
THURSDAY MORNING...BUT WILL BRING LARGE SURF AND DANGEROUS RIP
CURRENTS TO SOUTH FACING OCEAN BEACHES. A FRONT MAY STALL ACROSS
NEW ENGLAND...BRINGING UNSETTLED CONDITIONS SUNDAY INTO EARLY NEXT
WEEK.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
2 PM UPDATE...
TEMPERATURES...
FINALLY HIT 90 DEGREES AT LOGAN AT 139 PM THIS AFTERNOON. LAST
OCCURRENCE WAS 7/23 WHEN IT WAS 92. NOT MUCH CHANGE FROM PREVIOUS
FORECAST OTHER THAN INCREASING HIGHS BY A FEW DEGS. A MODEST SW
WIND 10 TO 20 MPH IS HELPING TO TAKE THE EDGE OFF THE HEAT ALONG
WITH DEW PTS REMAINING BELOW 70.
CONVECTION...
12Z NAM ALONG WITH LATEST HRRR AND RAP13 HAVE REALLY BACKED OFF ON
CONVECTIVE QPF AND HAVE DIMINISHED THE EASTWARD TREND...KEEPING
THE BULK OF ANY ACTIVITY ACROSS WESTERN NEW ENGLAND LATER THIS
AFTERNOON AND EVENING. THIS SEEMS REASONABLE GIVEN MARGINAL
INSTABILITY /500-1000J-KG/ ALONG WITH DEEP LAYER SHEAR AND JET
DYNAMICS ARRIVING 00Z-06Z...WELL AFTER PEAKING HEATING. THIS MAY
BE ABLE TO SUSTAIN SOME SHOWERS INTO THE COASTAL PLAIN THIS
EVENING BUT THUNDER NOT LIKELY. WORSE CASE SCENARIO REMAINS AN
ISOLATED STRONG T-STORM POSSIBLE WESTERN CT/MA WITH BRIEF GUSTY
WINDS AND HEAVY DOWNPOURS.
HIGH SURF...
FIRST SET OF SWELLS /SWELL FRONT/ APPEAR TO BE ON THE EDGE OF
ENTERING SOUTHERN NEW ENGLAND WATERS...WITH BUOY 44097 SOUTHEAST
OF BLOCK ISLAND NOW REPORTING 4 FT SWELLS EVERY 12 SECONDS. THIS
SHOULD RESULT IN SURF BUILDING RAPIDLY LATER THIS AFTERNOON AND
ESPECIALLY TOWARD SUNSET AT SOUTH AND SOUTHEAST FACING OCEAN
BEACHES.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM THURSDAY/...
TONIGHT...
CONSENSUS OF THE MODEL SOLUTIONS BRINGS THE COLD FRONT TO THE
COASTAL PLAIN AROUND SUNSET AND OFFSHORE EARLY TONIGHT. EXPECT
LINGERING SHOWER/TSTM THROUGH 10 PM IN RI AND EASTERN MASS...AND
THROUGH MIDNIGHT CAPE AND ISLANDS. WINDS TURN NORTHWEST BEHIND THE
COLD FRONT AND DRAW COOLER DRIER AIR DOWN FROM CANADA. THIS WILL
MEAN CLEARING SKIES AND DEW POINTS IN THE 50S AND LOWER 60S.
SWELL FROM HURRICANE CRISTOBAL CONTINUES TO INCREASE...WITH 5 FOOT
SWELL MOVING INTO OUR SOUTHERN WATERS EARLY TONIGHT. WE HAVE
ISSUED A HIGH SURF ADVISORY STARTING TONIGHT.
THURSDAY...
UPPER SHORTWAVE MOVES ACROSS NEW ENGLAND WITH BRIEF COOLING ALOFT.
MOISTURE FIELDS SHOW LINGERING 80 PCT RH VALUES BETWEEN 800 AND
900 MB. THIS SUGGESTS DIURNAL CUMULUS WILL FORM DURING THE DAY.
MIXING WILL REACH TO 850 MB WHERE TEMPS OF 10-12C WOULD SUPPORT
MAX SFC TEMPS IN THE UPPER 70S AND LOW 80S. WINDS ALOFT WITHIN THE
MIXED LAYER ARE FORECAST AT 20 KNOTS...WHICH MAY GET MIXED TO THE
SURFACE IN GUSTS.
HIGH SURF WILL CONTINUE THROUGH THE DAY AS CRISTOBAL PASSES WELL
OFFSHORE. THE HIGH SURFACE ADVISORY WILL CONTINUE THROUGH THE DAY.
&&
.LONG TERM /THURSDAY NIGHT THROUGH TUESDAY/...
HIGHLIGHTS...
* COOL AND DRY WEATHER UNDER HIGH PRESSURE FRIDAY
* WARM AND HUMID CONDITIONS INTO THE WEEKEND
* SCT SHOWERS/THUNDERSTORMS SUNDAY INTO EARLY NEXT WEEK
OVERVIEW AND MODEL PREFERENCES...
MEDIUM RANGE MODELS AND THEIR ENSEMBLES ALL CONTINUE TO SIGNAL A
LOW AMPLITUDE UPPER LEVEL PATTERN ACROSS THE NORTHERN TIER
STATES... WHICH GENERALLY MEANS A FAST MOVING PATTERN IN PLACE.
NOTING A DECENT SHORT WAVE DEVELOPING ACROSS THE GREAT LAKES LATE
THIS WEEK...THEN PUSHING ALONG IN THE GENERAL W-NW UPPER FLOW
TOWARD NEW ENGLAND. A FRONT ALSO TRIES TO SHIFT S...BUT BECOMES
PARALLEL TO THIS UPPER FLOW...SO MAY SEE UNSETTLED CONDITIONS MOVE
IN FOR SUNDAY AND LABOR DAY. NOTING INCREASING VARIANCE AMONGST
THE OP MODEL RUNS EARLY NEXT WEEK IN TRYING TO CLEAR THE SHORT
WAVE...WITH POSSIBLY ANOTHER WEAKER ONE MOVING IN.
LEANED TOWARD A BLEND OF AVAILABLE MODELS FOR THE EARLY PORTION OF
THE FORECAST...WHICH SHOWED GOOD CONTINUITY AND RUN TO RUN
CONSISTENCY OVER THE LAST SEVERAL MODEL RUNS...THEN TRENDED TOWARD
THE GFS/EC ENSEMBLES BEGINNING SUNDAY THROUGH TUESDAY.
DETAILS...
THURSDAY NIGHT THROUGH FRIDAY NIGHT...
EXPECT DRY AND COOL CONDITIONS AS LARGE HIGH PRES BUILDS OUT OF
THE GREAT LAKES...SHIFTING E IN THE BROAD UPPER LEVEL WESTERLY
WIND FLOW. WILL MAINLY CLEAR SKIES THU NIGHT AND WINDS BECOMING
LIGHT/VRBL MAINLY AFTER MIDNIGHT...TEMPS WILL TUMBLE...WITH
READINGS AWAY FROM THE IMMEDIATE COAST AND URBAN CENTERS DROPPING
TO THE MID 40S TO AROUND 50. SOME DIURNAL CLOUDS WILL DEVELOP
DURING FRIDAY...BUT IT WILL REMAIN COOL WITH HIGHS MAINLY IN THE
LOWER-MID 70S. NW WINDS MAY GUST UP TO AROUND 20 KT DURING THE
AFTERNOON.
CONDITIONS WILL REMAIN DRY FRI NIGHT...BUT THE HIGH WILL CREST
ACROSS THE REGION OVERNIGHT. EXPECT SOME MID AND HIGH LEVEL CLOUDS
WORKING IN WITH LOWS IN THE 50S.
SATURDAY...
TRANSITION DAY AS H5 SHORT WAVE MOVES OUT OF THE GREAT LAKES.
TEMPS WILL REBOUND AS W-SW WINDS KICK IN...BRINGING IN THE MILDER
CONDITIONS WITH INCREASING HUMIDITY ESPECIALLY LATE IN THE DAY
INTO SAT NIGHT. A FRONT WILL BEGIN TO SLOWLY SHIFT S OUT OF QUEBEC
AND S ONTARIO...SO MAY START TO SEE SOME SHOWERS MOVE INTO WESTERN
AREAS SAT NIGHT. CARRIED ONLY LOW CHANCE POPS AT THIS POINT. HIGHS
WILL BE IN THE 70S...UP TO AROUND 80 IN THE CT AND MERRIMACK
VALLEYS.
SUNDAY THROUGH MONDAY...
WITH THE HIGH ANCHORED OFF THE MID ATLC AND SE U.S. COAST...ALONG
WITH GENERAL W WIND FLOW ALOFT...THE FRONT THAT TRIES TO PUSH S
WILL GET HUNG UP IN THIS UPPER FLOW. THE SHORT WAVE WILL MOVE
ALONG THE FRONT...SO WILL SEE SCT SHOWERS PUSH ACROSS SUNDAY INTO
THE HOLIDAY...WITH BEST SHOT SUNDAY NIGHT AND MON MORNING. DEWPTS
ALSO INCREASE. PWATS WILL ALSO INCREASE...ON ORDER OF 1.7 TO 1.8
INCHES /ABOUT +2 SD FOR LATE AUGUST/. SOME MARGINAL INSTABILITY
ALSO WORKS IN...SO CAN NOT RULE OUT SOME THUNDERSTORMS. MAY ALSO
SEE A FEW PRODUCING LOCALLY HEAVY RAINFALL.
TEMPS WILL RISE TO THE UPPER 70S TO MID 80S...MILDEST ON
SUNDAY...WITH DEWPTS RISING TO THE MID 60S BOTH DAYS.
TUESDAY...
SOME QUESTION AS TO TIMING OF EXIT OF PRECIP...AND WHETHER
ANOTHER SHORT WAVE DEVELOPS AND PUSHES TOWARD THE REGION. FOR
NOW...EXPECT MAINLY DRY BUT WARM CONDITIONS...BUT NOT A LOT OF
CONFIDENCE FOR THIS PORTION OF THE FORECAST.
&&
.AVIATION /18Z WEDNESDAY THROUGH MONDAY/...
FORECASTER CONFIDENCE LEVELS...
LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.
SHORT-TERM /TODAY THROUGH THURSDAY/...MODERATE CONFIDENCE.
THRU 00Z...ANY -TSRA NOT FIRING UNTIL 20Z/21Z WESTERN NEW ENGLAND
WITH CHANCES FARTHER EAST FADING TOWARD 00Z. ACTIVITY WILL BE
ISOLATED OR WIDELY SCATTERED. VFR PREVAILS WITH LOW RISK OF BRIEF
MVFR IN -TSRA.
AFTER 00Z...ISOLATED TO WIDELY SCATTERED SHOWERS TIL 06Z THEN
MOVING OFFSHORE WITH FRONTAL PASSAGE AND WIND SHIFT FROM SW TO NW
06Z-12Z FROM NW TO SE. VFR PREVAILS WITH BRIEF MVFR POSSIBLE IN
ANY HEAVIER SHOWERS. LOW RISK OF BRIEF IFR SOUTH COAST UNTIL
FRONTAL PASSAGE 06Z-12Z.
THURSDAY...VFR. NORTHWEST WINDS MAY GUST TO 20 KNOTS WITH
SCATTERED TO BROKEN SKY COVER AROUND 5000 FEET FROM MIDDAY TO
EVENING.
THU NIGHT...VFR AND DRY WITH A MODEST NW WIND 10-20 KT DIMINISHING
TOWARD MORNING.
KBOS TERMINAL...HIGH CONFIDENCE IN TAF. ISOLATED -SHRA/-TSRA 22Z-
04Z POSSIBLE. GIVEN LIMITED AREAL COVERAGE DECIDED NOT TO INCLUDE
VCTS AND JUST GO WITH VCSH...THE HIGHER PROBABILITY.
KBDL TERMINAL...HIGH CONFIDENCE IN TAF. ISOLATED -SHRA/-TSRA
21Z-03Z. GIVEN LIMITED AREAL COVERAGE DECIDED NOT TO INCLUDE
VCTS AND JUST GO WITH VCSH...THE HIGHER PROBABILITY.
OUTLOOK...FRI THROUGH SUNDAY...
FRIDAY...HIGH CONFIDENCE. VFR WITH SKC THURSDAY NIGHT INTO
FRIDAY. LIGHT WINDS. PATCHY FOG AFTER 06Z FRI WITH LOCAL MVFR TO
IFR CONDITIONS POSSIBLE IN NORMALLY PRONE AREAS. SEA BREEZES
FRIDAY.
SATURDAY INTO SUNDAY...MODERATE CONFIDENCE.
VFR. INCREASING S-SW WINDS. BETTER CHANCES FOR SHRA/TSRA SUNDAY
ACROSS THE INTERIOR.
&&
.MARINE...
FORECASTER CONFIDENCE LEVELS...
LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.
SHORT-TERM /TODAY THROUGH THURSDAY/...HIGH CONFIDENCE.
2 PM UPDATE...
3-5 FT SOUTHERLY SWELLS WITH A PERIOD OF 12 SECONDS AT BUOY 44097
SOUTHEAST OF BLOCK ISLAND. THUS SWELLS FROM CRISTOBAL HAVE ENTERED
SOUTHERN NEW ENGLAND WATERS. EARLIER DISCUSSION BELOW.
============================================================
TODAY...HIGH PRESSURE OVER THE WATERS WILL SHIFT FARTHER OFFSHORE.
EXPECT LIGHT WINDS/PATCHY FOG FIRST THING THIS MORNING...OTHERWISE
GOOD VSBY WITH SOUTHWEST WINDS 10-15 KNOTS. AN APPROACHING COLD
FRONT MAY BRING SCATTERED SHOWERS/TSTMS TOWARD EVENING.
TONIGHT...INCREASING SOUTH SWELL FROM HURRICANE CRISTOBAL. THE
SOUTHERN WATERS WILL EXPERIENCE A 5 FOOT SWELL IN THE EARLY NIGHT
AND 6 TO 8 FOOT SWELL BY MORNING.
THURSDAY...SOUTH SWELL CONTINUES THROUGH THE DAY WITH 6 TO 9 FOOT
SEAS...MAINLY SWELL...ON THE SOUTHERN WATERS. NORTHWEST WIND WILL
BE GUSTY NEAR SHORE WITH MAXIMUM GUSTS AROUND 20 KNOTS.
OUTLOOK...THURSDAY NIGHT THROUGH SUNDAY...
THURSDAY NIGHT...HIGH CONFIDENCE.
EXPECT S SWELL FROM HURRICANE CRISTOBAL TO CONTINUE THROUGH THE
NIGHT...THOUGH MAY START TO SUBSIDE LATE. SEAS UP TO 7-9 FT ON THE
OUTER WATERS. N-NW WIND GUSTS UP TO 20 KT ON THE EASTERN OUTER
WATERS.
FRIDAY...HIGH CONFIDENCE.
N WINDS GUSTING TO 20 KT EARLY...THEN WILL VEER TO E-NE AND
DIMINISH DURING THE DAY. SEAS MAY LINGER AT AROUND 5 FT ON THE
OUTER WATERS DURING THE DAY BEFORE SUBSIDING.
SATURDAY AND SUNDAY...MODERATE CONFIDENCE.
WINDS BECOME S-SW DURING SAT AND CONTINUE THROUGH SUN. GUSTS
SHOULD REMAIN BELOW SMALL CRAFT CRITERIA...BUT SEAS MAY BUILD UP
TO AROUND 5 FT ON THE SOUTHERN OUTER WATERS.
&&
.BOX WATCHES/WARNINGS/ADVISORIES...
CT...AIR QUALITY ALERT UNTIL 9 PM EDT THIS EVENING FOR CTZ002>004.
MA...HIGH SURF ADVISORY FROM 8 PM THIS EVENING TO 8 PM EDT THURSDAY
FOR MAZ020-022>024.
NH...NONE.
RI...HIGH SURF ADVISORY FROM 8 PM THIS EVENING TO 8 PM EDT THURSDAY
FOR RIZ006>008.
AIR QUALITY ALERT UNTIL 11 PM EDT THIS EVENING FOR RIZ001>005.
MARINE...SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS FROM 5 PM THIS
AFTERNOON TO 8 PM EDT THURSDAY FOR ANZ235-237-254>256.
&&
$$
SYNOPSIS...WTB/EVT
NEAR TERM...NOCERA
SHORT TERM...WTB
LONG TERM...EVT
AVIATION...NOCERA/EVT
MARINE...WTB/EVT
AREA FORECAST DISCUSSION
NWS QUAD CITIES IA IL
124 PM CDT WED AUG 27 2014
.UPDATE...
ISSUED AT 1232 PM CDT WED AUG 27 2014
RECENT RUNS OF THE HRRR AND HOP-WRF SUGGEST SCATTERED SHOWERS AND
ISOLATED STORMS WILL LINGER ALONG AND SOUTH OF THE HIGHWAY 34
CORRIDOR THROUGH MID TO LATE AFTERNOON. PER THE LATEST SWOMCD...AN
ISOLATED NEAR SEVERE STORM IS NOT TOTALLY OUT OF THE QUESTION IN
THE EXTREME SOUTH. OTHERWISE...MORE WIDESPREAD CONVECTION STILL ON
TARGET FOR LATE TONIGHT INTO THURSDAY MORNING WITH SCATTERED
COVERAGE LIKELY LINGERING INTO THE AFTERNOON.
&&
.SYNOPSIS...
ISSUED AT 331 AM CDT WED AUG 27 2014
AT 3 AM...MSAS SURFACE PRESSURE FIELDS INDICATED HIGH PRESSURE OVER
NORTHERN MN...WITH THE SURFACE FRONT WELL SOUTH ALONG THE I-70
CORRIDOR IN IL AND MO. AREA RADARS SHOWED SCATTERED...ELEVATED
WEAK SHOWERS STREAMING EAST ALONG THE I-80 CORRIDOR FROM DSM TO
THE QUAD CITIES WITH A ISOLATED SHOWERS OVER SE IA AND W CENTRAL
IL. A MORE SIGNIFICANT...AND SO FAR SLOW MOVING...MCS WAS ALONG
THE IA/NE/MO BORDER AREA...IN AN AXIS OF MORE SIGNIFICANT 850
THETAE CONVERGENCE. VERY LIGHT NORTH TO NORTHEAST WINDS OUT OF THE
MN HIGH WAS PULLING IN COOLER AND DRIER AIR AT THE LOW
LEVELS...WITH WIDESPREAD TEMPERATURES IN THE MID TO UPPER 60S AND
A FEW READINGS NEAR 70 IN THE FAR SOUTH.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 331 AM CDT WED AUG 27 2014
IN THE NEAR TERM...ELEVATED THETAE CONVERGENCE FIELDS IN THE
RAP...WHICH HAD A GOOD CORRELATION WITH THE STORMS IN SW IA...WOULD
SUPPORT THE STORM CLUSTER SLOWLY DRIFTING EAST THROUGH
SUNRISE...REACHING THE FAR SOUTHWEST AND SOUTH BEFORE DISSIPATING BY
MID MORNING. ELSEWHERE...THERE IS NOT MUCH SUPPORT OR MID LEVEL
INSTABILITY TO SUGGEST THE ELEVATED SHOWERS AND ISOLATED
THUNDERSTORMS OVER THE CENTRAL AND SOUTH WILL RAMP UP LIKE PREVIOUS
MORNINGS AND WILL MAINTAIN LOW CHANCE POPS. HIGHER CHANCE POPS ARE
MAINTAINED MAINLY SOUTH OF THE HIGHWAY 34 CORRIDOR IN SE IA...WHERE
WEAK MOISTURE CONVERGENCE AT 850 MB CONTINUES THIS MORNING.
BEYOND...RAIN CHANCES HAVE BEEN REMOVED OVER ALL BUT THE FAR SOUTH
FROM LATE MORNING THROUGH AFTERNOON AS A LOW LEVEL EASTERLY FLOW
CONTINUES TO ADVECT IN DRIER AIR UNDER A WEAK MID LEVEL RIDGE.
TEMPERATURES WILL BE SIMILAR TO A BIT COOLER THAN YESTERDAY DUE TO
THE EASTERLY FLOW AND LIKELY INCREASED CLOUD COVER.
TONIGHT...ALL MODELS HAVE THE NEXT MCS DEVELOPING OVER WESTERN OR NW
IA AROUND MIDNIGHT...EXPANDING EAST TOWARD MORNING. HAVE ADJUSTED
POPS ACCORDINGLY...WITH MUCH SLOWER TIMING RESULTING IN A DRY NIGHT
IN THE EAST AND LATER ONSET CENTRAL AND WEST. HEAVY RAINFALL DOES
NOT LOOK TO BE A MAJOR THREAT AS MCS GENERATION AND MAINTENANCE
TOOLS POINT TOWARD THE BEST FORCING NOT ADVANCING MUCH PAST NW OR
POSSIBLY N CENTRAL IA BY 12Z.
.LONG TERM...(THURSDAY THROUGH TUESDAY)
ISSUED AT 331 AM CDT WED AUG 27 2014
THERE SHOULD BE A RESPECTABLE THUNDERSTORM COMPLEX ACROSS NORTHERN
IOWA THURSDAY MORNING WITH A WING OF CONVECTION MOVING ACROSS THE
AREA. THE NORTHWEST HALF OF THE AREA HAS THE BETTER CHANCES FOR
RAIN. BOUNDARIES LEFT OVER FROM THE MORNING STORM COMPLEX WILL
PROVIDE THE FOCUS FOR SCATTERED CONVECTION IN THE AFTERNOON AND
EVENING.
ALTHOUGH THE SIGNAL IS NOT AS CLEAR...ANOTHER ORGANIZED THUNDERSTORM
COMPLEX SHOULD DEVELOP WEST OF THE AREA THURSDAY EVENING AND MOVE
EAST NORTHEAST LATE THURSDAY NIGHT INTO FRIDAY MORNING. THE
NORTHWEST THIRD TO HALF OF THE AREA HAS THE BETTER CHANCES FOR RAIN.
BOUNDARIES FROM THE FRIDAY MORNING STORM COMPLEX WOULD AGAIN PROVIDE
THE FOCUS FOR SCATTERED CONVECTION THAT DEVELOPS FRIDAY AFTERNOON
AND EVENING.
LATE FRIDAY NIGHT ANOTHER FRONT OR BOUNDARY IS FORECAST TO BEGIN
MOVING INTO THE AREA. THE COMBINATION OF MOISTURE AND FORCING SHOULD
RESULT IN SCATTERED CONVECTION PERSISTING THROUGH SUNRISE SATURDAY.
SATURDAY ON...
THE OVERALL WEATHER PATTERN IS SUPPORTIVE OF NOCTURNAL THUNDERSTORM
COMPLEXES ACROSS THE MIDWEST. WHERE EACH DEVELOPS AND MOVES AFFECTS
SUBSEQUENT DEVELOPMENT. AS A RESULT...THERE WILL BE PERIODS OF DRY
WEATHER THAT MAY BE 6-12 HOURS IN DURATION.
TEMPERATURES SATURDAY THROUGH TUESDAY SHOULD BE NEAR NORMAL.
THE MODEL CONSENSUS HAS CHANCE TO LIKELY POPS FOR SATURDAY AND
SLIGHT CHANCE TO CHANCE POPS SATURDAY NIGHT.
THE MODEL CONSENSUS HAS SLIGHT CHANCE POPS FOR THE AREA
SUNDAY/SUNDAY NIGHT. SEVERAL MODELS ARE SUGGESTING HIGH PRESSURE
MOVING THROUGH THE AREA ON SUNDAY WHICH MAY RESULT IN DRY CONDITIONS.
MONDAY THROUGH TUESDAY THE MODEL CONSENSUS HAS CHANCE POPS FOR EACH
12 HOUR PERIOD.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z THURSDAY AFTERNOON)
ISSUED AT 1232 PM CDT WED AUG 27 2014
ISOLD SHOWERS WILL CONTINUE INVOF KBRL THIS AFTERNOON.
OTHERWISE...EXPECT VFR CONDITIONS UNTIL LATE TONIGHT...WHEN
THUNDERSTORMS ARE FORECAST TO BECOME WIDESPREAD ACROSS EASTERN
IOWA INTO NORTHWEST ILLINOIS. HAVE INTRODUCED PREVAILING TSRA
GROUPS WITH MVFR CIGS/VSBYS AT KCID/KDBQ/KBRL BETWEEN 09Z-11Z.
TIMING EXPECTED TO BE SLIGHTLY LATER AT KMLI.
&&
.DVN WATCHES/WARNINGS/ADVISORIES...
IA...NONE.
IL...NONE.
MO...NONE.
&&
$$
UPDATE...RP KINNEY
SYNOPSIS...SHEETS
SHORT TERM...SHEETS
LONG TERM...08
AVIATION...RP KINNEY
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
132 PM CDT WED AUG 27 2014
...UPDATE TO LONG TERM...
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 202 AM CDT WED AUG 27 2014
SUBTLE UPPER LEVEL DISTURBANCES EMBEDDED IN A SOUTHWEST FLOW WILL
CROSS THE CENTRAL PLAINS OVER THE NEXT 36 TO 48 HOURS AS THE MAIN
UPPER LEVEL TROUGH MOVES SLOWLY EAST ACROSS THE FOUR CORNERS
REGION. EARLIER THIS MORNING THE WATER VAPOR LOOP, AND 00Z
WEDNESDAY UPPER AIR ANALYSIS PLACED ONE OF THE UPPER WAVES WERE
LOCATED OVER NORTHEAST NEW MEXICO. RADAR MOSAIC AND SURFACE
OBSERVATION INDICATED SCATTERED SHOWERS AND THUNDERSTORMS WERE
OCCURRING AHEAD OF THIS FEATURE ACROSS THE OKLAHOMA AND TEXAS
PANHANDLE. NAM, GFS, AND HRRR WERE ALL IN GOOD AGREEMENT IN MOVING
THIS AREA OF PRECIPITATION ACROSS WESTERN KANSAS DURING THE EARLY
MORNING HOURS AND BASED ON 06Z VERIFICATION OF THE UPPER WAVE AND
AREA FAVORABLE FOR PRECIPITATION THESE MODELS APPEAR TO HAVE A
GOOD HANDLE ON THIS EARLY MORNING EVENT. WILL THEREFORE KEEP HIGH
CHANCE OR EVEN LIKELY WORDING FOR THUNDERSTORMS THROUGH AT LEAST
15Z ACROSS NORTH CENTRAL AND MUCH OF WESTERN KANSAS AS THE UPPER
WAVE PASSES.
AS THIS FIRST SYSTEM LIFTS NORTHEAST TOWARDS SOUTHERN NEBRASKA
LATER THIS MORNING...A SECOND UPPER LEVEL DISTURBANCE WILL BEGIN
TO APPROACH THE AREA FROM THE SOUTHWEST. THIS NEXT SYSTEM APPEARS
TO BE LOCATED NEAR THE NOSE OF AN 300MB JET STREAK AND IS
CURRENTLY FORECAST TO CROSS WESTERN KANSAS LATE THIS AFTERNOON AND
EARLY THIS EVENING. GIVEN THE LOCATION OF AN UPPER LEVEL JET LATE
TODAY/EARLY EVENING ALONG WITH MOISTURE, AND INSTABILITY AHEAD OF
THIS NEXT DISTURBANCE WILL INCREASE PRECIPITATION CHANCES DURING
THE AFTERNOON AND EARLY EVENING. MAIN HAZARD CURRENTLY APPEARS TO
BE PERIODS OF HEAVY RAINFALL, HOWEVER A FEW OF THE STRONGER
THUNDERSTORMS IN WEST CENTRAL AND PARTS OF NORTH CENTRAL KANSAS
MAY ALSO PRODUCE HAIL AND STRONG GUSTY WINDS.
AS FOR TEMPERATURES TODAY WILL UNDERCUT GUIDANCE AND TREND
TOWARDS WHAT THE 850MB 00Z THURSDAY MIX DOWN TEMPERATURES
SUGGESTED FOR HIGHS. GIVEN THE EXPECTED CLOUD COVER AND THE 00Z
850MB TEMPERATURES WILL FAVOR AFTERNOON TEMPERATURES MAINLY IN THE
MID 80S ACROSS WEST CENTRAL KANSAS AND UPPER 80S TO NEAR 90
ELSEWHERE. IN SOUTH CENTRAL KANSAS WHERE MORE SUN AND LESS CLOUDS
ARE EXPECTED WILL TREND SLIGHTLY WARMER.
.LONG TERM...(THURSDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 128 PM CDT WED AUG 27 2014
SHOWERS AND ISOLATED THUNDERSTORMS WILL LINGER ACROSS CENTRAL AND
EASTERN PORTIONS OF WESTERN KANSAS FRIDAY AS AN UPPER LEVEL
SHORTWAVE PUSHES EASTWARD OUT OF THE WESTERN HIGH PLAINS INTO THE
CENTRAL PLAINS EARLY IN THE PERIOD. AS THE UPPER LEVEL SHORTWAVE
MOVES ACROSS THE REGION, A PREVAILING SOUTHEASTERLY FLOW WILL
CONTINUE TO DRAW MOISTURE UP INTO CENTRAL KANSAS AHEAD OF A SURFACE
TROUGH EDGING EASTWARD ACROSS THE AREA. MEANWHILE, A +60KT UPPER
LEVEL JET CORE ASSOCIATED WITH THE SHORTWAVE IS PROJECTED TO LIFT
NORTHEAST AS IT SHIFTS EAST ACROSS WESTERN AND CENTRAL KANSAS. ALONG
WITH THE INCREASED DYNAMIC SUPPORT ALOFT PRESENT, SHOWERS AND
THUNDERSTORMS ARE LIKELY EARLY FRIDAY ACROSS CENTRAL KANSAS IN A
CORRIDOR OF INCREASED INSTABILITY ALONG AND AHEAD OF THE SURFACE
TROUGH AS IT MOVES THROUGH. DRIER CONDITIONS ARE THEN EXPECTED
ACROSS WESTERN KANSAS THROUGH THE WEEKEND AS THE UPPER LEVEL
SHORTWAVE KICKS EAST OUT OF THE CENTRAL PLAINS WHILE WEAK RIDGING
ALOFT MOVES OUT OF THE ROCKIES INTO THE WESTERN HIGH PLAINS.
BELOW NORMAL TEMPERATURES ARE EXPECTED FRIDAY AS SLIGHTLY COOLER AIR
BEGINS TO FILTER SOUTHWARD INTO WESTERN KANSAS IN WAKE OF THE
SURFACE TROUGH PASSING THROUGH. THE GFS AND ECMWF SHOW H85
TEMPERATURES AROUND 20C ACROSS CENTRAL KANSAS WITH NEAR 25C IN
EXTREME SOUTHWEST KANSAS. ALTHOUGH INCREASED CLOUD COVER MAY BE
PRESENT EARLY IN THE DAY, LOOK FOR HIGHS GENERALLY UP INTO THE LOWER
TO MID 80S(F) FRIDAY AFTERNOON. A WARMING TREND IS THEN EXPECTED
THROUGH THE WEEKEND AS A WEAK UPPER LEVEL RIDGE TRANSITIONS EAST
ACROSS THE CENTRAL PLAINS.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z THURSDAY AFTERNOON)
ISSUED AT 1210 PM CDT WED AUG 27 2014
THERE IS PLENTY OF MOISTURE IN THE AIR, AND MID LEVEL CLOUDS
BLANKET THE TAF AREA. A RATHER STRONG UPPER LEVEL WAVE WILL MOVE
IN FROM THE NORTHWEST THIS EVENING, AND THERE IS A CHANCE FOR SOME
STRONG STORMS AT EACH TAF SITE FROM APPROXIMATELY 21Z-03Z. CIGS
MAY GO DOWN TO OVC050 AND VSBYS TO 4-5SM IN RAIN AND FOG, BUT IFR
CONDITIONS ARE NOT ANTICIPATED. OVERNIGHT, EXPECT SOUTHEAST WINDS
OF 10 TO 13 KNOTS AND CIGS IN THE BKN090 RANGE.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 67 86 63 83 / 50 50 70 40
GCK 66 84 62 83 / 60 50 60 20
EHA 64 83 61 82 / 50 50 60 20
LBL 67 86 64 82 / 50 50 60 20
HYS 68 85 65 83 / 60 50 60 40
P28 71 88 67 85 / 40 60 70 40
&&
.DDC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...BURGERT
LONG TERM...JJOHNSON
AVIATION...BURKE
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
1217 PM CDT WED AUG 27 2014
...UPDATED FOR THE AVIATION DISCUSSION...
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 202 AM CDT WED AUG 27 2014
SUBTLE UPPER LEVEL DISTURBANCES EMBEDDED IN A SOUTHWEST FLOW WILL
CROSS THE CENTRAL PLAINS OVER THE NEXT 36 TO 48 HOURS AS THE MAIN
UPPER LEVEL TROUGH MOVES SLOWLY EAST ACROSS THE FOUR CORNERS
REGION. EARLIER THIS MORNING THE WATER VAPOR LOOP, AND 00Z
WEDNESDAY UPPER AIR ANALYSIS PLACED ONE OF THE UPPER WAVES WERE
LOCATED OVER NORTHEAST NEW MEXICO. RADAR MOSAIC AND SURFACE
OBSERVATION INDICATED SCATTERED SHOWERS AND THUNDERSTORMS WERE
OCCURRING AHEAD OF THIS FEATURE ACROSS THE OKLAHOMA AND TEXAS
PANHANDLE. NAM, GFS, AND HRRR WERE ALL IN GOOD AGREEMENT IN MOVING
THIS AREA OF PRECIPITATION ACROSS WESTERN KANSAS DURING THE EARLY
MORNING HOURS AND BASED ON 06Z VERIFICATION OF THE UPPER WAVE AND
AREA FAVORABLE FOR PRECIPITATION THESE MODELS APPEAR TO HAVE A
GOOD HANDLE ON THIS EARLY MORNING EVENT. WILL THEREFORE KEEP HIGH
CHANCE OR EVEN LIKELY WORDING FOR THUNDERSTORMS THROUGH AT LEAST
15Z ACROSS NORTH CENTRAL AND MUCH OF WESTERN KANSAS AS THE UPPER
WAVE PASSES.
AS THIS FIRST SYSTEM LIFTS NORTHEAST TOWARDS SOUTHERN NEBRASKA
LATER THIS MORNING...A SECOND UPPER LEVEL DISTURBANCE WILL BEGIN
TO APPROACH THE AREA FROM THE SOUTHWEST. THIS NEXT SYSTEM APPEARS
TO BE LOCATED NEAR THE NOSE OF AN 300MB JET STREAK AND IS
CURRENTLY FORECAST TO CROSS WESTERN KANSAS LATE THIS AFTERNOON AND
EARLY THIS EVENING. GIVEN THE LOCATION OF AN UPPER LEVEL JET LATE
TODAY/EARLY EVENING ALONG WITH MOISTURE, AND INSTABILITY AHEAD OF
THIS NEXT DISTURBANCE WILL INCREASE PRECIPITATION CHANCES DURING
THE AFTERNOON AND EARLY EVENING. MAIN HAZARD CURRENTLY APPEARS TO
BE PERIODS OF HEAVY RAINFALL, HOWEVER A FEW OF THE STRONGER
THUNDERSTORMS IN WEST CENTRAL AND PARTS OF NORTH CENTRAL KANSAS
MAY ALSO PRODUCE HAIL AND STRONG GUSTY WINDS.
AS FOR TEMPERATURES TODAY WILL UNDERCUT GUIDANCE AND TREND
TOWARDS WHAT THE 850MB 00Z THURSDAY MIX DOWN TEMPERATURES
SUGGESTED FOR HIGHS. GIVEN THE EXPECTED CLOUD COVER AND THE 00Z
850MB TEMPERATURES WILL FAVOR AFTERNOON TEMPERATURES MAINLY IN THE
MID 80S ACROSS WEST CENTRAL KANSAS AND UPPER 80S TO NEAR 90
ELSEWHERE. IN SOUTH CENTRAL KANSAS WHERE MORE SUN AND LESS CLOUDS
ARE EXPECTED WILL TREND SLIGHTLY WARMER.
.LONG TERM...(THURSDAY THROUGH TUESDAY)
ISSUED AT 306 AM CDT WED AUG 27 2014
AN UPPER LEVEL LOW WILL MOVE THROUGH THE CENTRAL ROCKIES THURSDAY
THEN THROUGH THE CENTRAL PLAINS FRIDAY BEFORE WEAKENING AND
EXITING INTO THE UPPER MISSISSIPPI VALLEY ON SATURDAY. THIS
FEATURE WILL HELP PUSH A SURFACE COLD FRONT THROUGH WESTERN KANSAS
THURSDAY INTO THURSDAY NIGHT. THE FRONT WILL THEN BE POSITIONED
ACROSS CENTRAL KANSAS ON FRIDAY. LOWER AND MID LEVELS OF THE
ATMOSPHERE WILL BE SATURATED AND WITH THE LIFT CREATED BY THIS
SYSTEM, MOSTLY CLOUDY SKIES ARE EXPECTED THROUGH FRIDAY. STORM
CHANCES WILL ALSO BE PRESENT THROUGH FRIDAY WITH THE BEST CHANCE
OCCURRING THURSDAY AFTERNOON INTO THURSDAY NIGHT WHEN THE COLD
FRONT MOVES ACROSS THE CWA. THUNDERSTORM CHANCES END FROM WEST TO
EAST ON FRIDAY THEN BE CONFINED ACROSS CENTRAL AND EASTERN KANSAS
BY SATURDAY. A DRIER PERIOD IS THEN EXPECTED THROUGH THIS WEEKEND
INTO THE BEGINNING OF NEXT WEEK AS A WEAK UPPER LEVEL RIDGE MOVING
THROUGH THE ROCKIES AND HIGH PRESSURE BUILDING ACROSS THE AREA AT
THE SURFACE. MEANWHILE, A UPPER LEVEL LONG WAVE TROUGH IS PROGGED
TO DIG INTO THE PACIFIC NORTHWEST AND INTER-MOUNTAIN WEST THIS
WEEKEND INTO THE FIRST PART OF NEXT WEEK, THEN MOVE INTO THE THE
NORTHERN PLAINS BY MID WEEK. THIS COULD BRING A CHANCE OF
THUNDERSTORMS TUESDAY INTO WEDNESDAY, HOWEVER, IT IS TOO FAR OUT
TO PIN POINT EXACTLY THE BEST LIFT WILL OCCUR. OTHERWISE EXPECT
PARTLY CLOUDY SKIES SATURDAY THROUGH THE MIDDLE OF NEXT WEEK. AS
FOR TEMPERATURES, HIGHS LOOK TO BE IN THE 80S THURSDAY THROUGH
SATURDAY THEN INCREASE INTO THE LOWER TO MID 90S ON SUNDAY. HIGHS
MONDAY THROUGH WEDNESDAY ARE FORECASTED TO RANGE FROM THE UPPER
80S ACROSS WEST CENTRAL KANSAS TO MID 90S ACROSS SOUTH CENTRAL
KANSAS. LOWS THROUGH THE EXTENDED PERIOD LOOK TO GENERALLY BE IN
THE 60S WITH A FEW LOWER 70S ACROSS SOUTH CENTRAL KANSAS MONDAY
AND TUESDAY MORNINGS.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z THURSDAY AFTERNOON)
ISSUED AT 1210 PM CDT WED AUG 27 2014
THERE IS PLENTY OF MOISTURE IN THE AIR, AND MID LEVEL CLOUDS
BLANKET THE TAF AREA. A RATHER STRONG UPPER LEVEL WAVE WILL MOVE
IN FROM THE NORTHWEST THIS EVENING, AND THERE IS A CHANCE FOR SOME
STRONG STORMS AT EACH TAF SITE FROM APPROXIMATELY 21Z-03Z. CIGS
MAY GO DOWN TO OVC050 AND VSBYS TO 4-5SM IN RAIN AND FOG, BUT IFR
CONDITIONS ARE NOT ANTICIPATED. OVERNIGHT, EXPECT SOUTHEAST WINDS
OF 10 TO 13 KNOTS AND CIGS IN THE BKN090 RANGE.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 90 67 86 63 / 60 50 50 70
GCK 87 66 84 62 / 50 60 50 60
EHA 87 64 83 61 / 40 50 40 60
LBL 91 67 86 64 / 40 50 40 60
HYS 88 68 85 65 / 50 60 50 60
P28 93 71 88 67 / 20 40 60 70
&&
.DDC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...BURGERT
LONG TERM...HOVORKA_42
AVIATION...BURKE
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
133 PM EDT WED AUG 27 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 349 AM EDT WED AUG 27 2014
MUCH OF THE FOCUS OF THE SHORT TERM FORECAST IS WITH THE SHORTWAVE
QUICKLY MOVING EAST-SOUTHEAST INTO THE UPPER GREAT LAKES REGION.
THE AXIS OF THE SHORTWAVE IS LOCATED IN NORTHERN MINNESOTA AT
07Z...BUT THERE ARE TWO AREAS OF SHOWERS AHEAD OF THIS WAVE...ONE
STRETCHING FROM ISLE ROYALE TO LITTLE FALLS MINNESOTA AND THE OTHER
FROM WESTERN MARQUETTE COUNTY TO EAU CLAIRE WISCONSIN. EVEN THOUGH
THE 00Z KMPX RAOB INDICATED DRY AIR BELOW THE CLOUDS BASE...RAIN
HAS BEEN REACHING THE GROUND UNDER MOST OF THE RADAR RETURNS AND
GENERALLY PRODUCING ANYWHERE FROM A TRACE TO 0.05IN OF RAIN AS IT
HAS MOVED THROUGH MINNESOTA AND NORTHWEST WISCONSIN. EXPECT THESE
SHOWERS TO CONTINUE TO THE EAST AS THE SHORTWAVE QUICKLY MOVES
THROUGH THE WEST HALF OF UPPER MICHIGAN BY 12Z AND OUT OF THE ENTIRE
AREA BY 15Z. THE 04Z/05Z HRRR RUNS HAVE HAD A DECENT HANDLE ON
PRECIP AND WEIGHTED THE POP FORECAST TOWARDS THAT FOR THE FIRST
6HRS. THEREFORE...HAVE SHOWN SCATTERED/ISOLATED SHOWERS MOVING
THROUGH THE CWA THIS MORNING AND QUICKLY COMING TO AN END FROM WEST
TO EAST. BEHIND THE SHORTWAVE...DRY AIR ASSOCIATED WITH A HIGH
CURRENTLY CENTERED IN MINNESOTA WILL QUICKLY MOVE OVER MUCH OF THE
AREA AND LEAD TO ANOTHER COOL DAY ACROSS THE U.P.
EXPECT SOME DIURNAL CLOUD DEVELOPMENT AFTER THE MID CLOUDS
DEPART...AS A POCKET OF MOISTURE AROUND 850MB OR 4KFT SEEN OVER LAKE
SUPERIOR THIS PAST EVENING AND KCMX OBS OVERNIGHT GRADUALLY SHIFTS
SOUTHEAST AND DISSIPATES. WITH THE LIGHT WEST-NORTHWEST FLOW IN THE
LOW LEVELS...EXPECT THE CLOUDS TO BE INLAND FROM LAKE SUPERIOR AND
GENERALLY OVER CENTRAL/EASTERN UPPER MICHIGAN. HIGHS TODAY WILL BE
SIMILAR TO YESTERDAY OVER THE WEST THIRD (MID-UPPER 60S) AND
SLIGHTLY COOLER OVER THE CENTRAL/EAST (65-71).
HIGH PRESSURE WILL REMAIN IN PLACE TONIGHT AND PRODUCE MOSTLY CLEAR
SKIES (JUST A FEW HIGH CLOUDS APPROACHING FROM THE SOUTHWEST AHEAD
OF THE NEXT SHORTWAVE). THE MOSTLY CLEAR SKIES...LIGHT WINDS...AND
PWATS AROUND 45 PERCENT OF NORMAL WILL LEAD TO A GOOD RADIATIONAL
COOLING NIGHT. HAVE THE INTERIOR LOCATIONS FALLING INTO THE LOWER
40S TO UPPER 30S...WHICH IS A LITTLE COOLER THAN THE PREVIOUS
FORECAST. WOULD NOT BE SURPRISED IF SOME OF THE TRADITIONAL COLD
RAWS SITES REACH THE MIDDLE 30S AND DID DROP A FEW OF THEM TO THOSE
VALUES (WHICH COULD LEAD TO SOME PATCHY FROST). WILL CONTINUE THE
MENTION OF PATCHY RADIATIONAL/GROUND FOG FOR TONIGHT...BUT DON/T
EXPECT IT TO BE TOO THICK DUE TO THE EXISTING DRY AIR. THE PLACES
WHERE IT SHOULD BE THE THICKEST WOULD BE IN ANY LOW SPOTS OR NEAR
LAKES (DUE TO THEIR WARMER WATER TEMPERATURES).
.LONG TERM...(THURSDAY THROUGH TUESDAY)
ISSUED AT 519 AM EDT WED AUG 27 2014
THRU THE BEGINNING OF THE UPCOMING WEEKEND...A LOW AMPLITUDE
PROGRESSIVE NRN STREAM FLOW REGIME WILL PREVAIL ACROSS SRN CANADA. A
WEAKER SRN BRANCH FLOW ACROSS THE CONUS WILL CAUSE ISSUES WITH
REGARD TO PCPN OVER THE UPPER LAKES...DEPENDING ON INTERACTION OF
SHORTWAVES WITH THE MORE PROGRESSIVE FLOW TO THE N. RIGHT NOW...THE
SRN BRANCH FEATURES A TROF AND WELL-DEFINED SHORTWAVE OVER THE SRN
ROCKIES. EARLY NEXT WEEK...FLOW WILL AMPLIFY SOME AS A MORE
SUBSTANTIAL TROF MOVES INTO THE NW CONUS AND THEN SHIFTS EASTWARD.
OVERALL...THIS PATTERN WILL SUPPORT TEMPS GENERALLY AROUND NORMAL TO
A BIT BLO OVER THE NEXT FEW DAYS. BRIEF WARMING WILL OCCUR EARLY
NEXT WEEK AHEAD OF THE MORE SUBSTANTIAL TROF PROGRESSING E ACROSS
THE NW AND NCNTRL CONUS. PCPN FCST IS QUITE UNCERTAIN. THERE IS THE
POTENTIAL FOR AT LEAST A COUPLE OF ROUNDS OF PCPN THRU THE UPCOMING
WEEKEND...DEPENDING ON EVOLUTION OF SRN BRANCH SHORTWAVES. ANOTHER
PERIOD OF PCPN SHOULD OCCUR EARLY NEXT WEEK AS COLD FRONT SWEEPS
ACROSS THE AREA IN ASSOCIATION WITH AFOREMENTIONED TROF MOVING
ACROSS THE NW/NCNTRL CONUS.
BEGINNING THU/FRI...ATTENTION TURNS TO SHORTWAVE LIFTING OUT OF THE
SRN BRANCH TROF CURRENTLY OVER THE SRN ROCKIES. WITH NRN STREAM
TROFS MOVING ACROSS THE CANADIAN ROCKIES AND QUEBEC/NEW ENGLAND...
THERE WILL BE AN OPPORTUNITY FOR THE SRN BRANCH SHORTWAVE TO MAKE
SOME NORTHWARD PROGRESS. MODELS HAVE OVERALL MOVED INTO BETTER
AGREEMENT ON WAA/MOISTURE ADVECTION LIFTING N AND SPREADING PCPN
INTO UPPER MI THU NIGHT/FRI. HOWEVER...THERE ARE STILL SOME
DIFFERENCES AS THE GEM/ECMWF/NAM ARE MORE AGGRESSIVE SPREADING MAIN
AREA OF PCPN MORE SQUARELY ACROSS THE FCST AREA. THE GFS IS FOCUSED
MORE TO THE S AND E. GIVEN TRENDS AND GFS SOMEWHAT ON ITS OWN...
RAISED POPS SOME FOR LATER THU NIGHT/FRI MORNING WITH LIKELY POPS
FROM THE SCNTRL TO THE ERN FCST AREA. WILL NEED TO CONTINUE UPWARD
TREND IF NEXT ROUND OF MODELS STAYS ON TRACK. INSTABILITY IS RATHER
LIMITED. ONLY INCLUDED THUNDER SCNTRL AND E. AFTER SOME PATCHY FOG
EARLY THU...SUNSHINE WILL GIVE WAY TO INCREASING HIGH CLOUDS. MIXING
TO 850-800MB ON FCST SOUNDINGS SUGGEST HIGH TEMPS THU WILL BE MOSTLY
IN THE LOW/MID 70S AWAY FROM LAKE COOLING.
OVER THE WEEKEND...FCST HAS BECOME MORE UNCERTAIN AS THERE IS A
TREND FOR THE MAIN ENERGY CURRENTLY IN THE SRN ROCKIES TROF TO LIFT
FARTHER N. ASSOCIATED WEAK SFC WAVE IS FCST TO TRACK ACROSS SRN WI
AND THRU NRN LWR MI. GIVEN TRENDS ALONG WITH DECENT AGREEMENT AMONG
00Z MEDIUM RANGE GUIDANCE...WILL LINGER CHC POPS OVER THE SE HALF OF
THE FCST AREA FRI NIGHT...THEN SPREAD CHC POPS BACK N AND W SAT/SAT
NIGHT. LOOKS LIKE SUN SHOULD DRY OUT WITH SHORTWAVE RIDGE ARRIVING
BTWN DEPARTING SHORTWAVE AND AHEAD OF MORE SIGNIFICANT TROF
DEVELOPING INTO THE NW CONUS.
AS THE MORE SUBSTANTIAL TROF OVER THE NW CONUS SHIFTS EASTWARD EARLY
NEXT WEEK...A COLD FRONT WILL SWEEP E ACROSS THE GREAT LAKES...
BRINGING A DECENT POTENTIAL FOR SHRA/TSRA. FOR THIS FAR OUT IN THE
MODEL RUNS...AGREEMENT IS GOOD ON TIMING FRONT. THE ECMWF HAS
NOTABLY TRENDED FASTER TOWARD THE GFS WHICH IS TYPICALLY MORE
PROGRESSIVE...AND THE GEM OFFERS SIMILAR TIMING. THESE LATEST RUNS
SUGGEST FRONT CROSSING UPPER MI MON AFTN/NIGHT. SO IT LOOKS LIKE
LABOR DAY MIGHT TURN WET WITH SHRA AND TSTMS SPREADING E ACROSS THE
AREA.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z THURSDAY AFTERNOON)
ISSUED AT 133 PM EDT WED AUG 27 2014
VFR CONDITIONS ARE EXPECTED THROUGH THE PERIOD AT ALL SITES...EXCEPT
FOR SOME MVFR VIS AT SAW OVERNIGHT. SCATTERED TO BROKEN LOW-END VFR
STRATOCUMULUS WILL DISSIPATE BY AROUND 00Z. HIGH PRESSURE WILL THEN
BRING MOSTLY CLEAR SKIES AND LIGHT WINDS TONIGHT...ALLOWING FOR
PATCHY BR TO DEVELOP AT SAW. VIS MAY FLUCTUATE CONSIDERABLY DURING
THE OVERNIGHT HOURS...BUT ANY BR OR FG SHOULD BE QUITE SHALLOW AND
DISSIPATE SHORTLY AFTER SUNRISE THURSDAY.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 349 AM EDT WED AUG 27 2014
HIGH PRESSURE MOVING THROUGH THE UPPER GREAT LAKES REGION TODAY AND
THURSDAY WILL LEAD TO WINDS STAYING BELOW 15KTS. THIS HIGH WILL
SHIFT EAST THURSDAY NIGHT...ALLOWING A COUPLE WEAK SURFACE TROUGHS
TO MOVE THROUGH THE REGION. THE WEAK PRESSURE GRADIENT ASSOCIATED
WITH THESE TROUGHS WILL KEEP WINDS BELOW 20KTS.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...SRF
LONG TERM...ROLFSON
AVIATION...KLUBER
MARINE...SRF
AREA FORECAST DISCUSSION
NWS BISMARCK ND
1257 PM CDT WED AUG 27 2014
.UPDATE...
ISSUED AT 1258 PM CDT WED AUG 27 2014
HIGH PRESSURE OVER THE AREA WILL MOVE EAST TODAY. MAINLY CLEAR
SKIES NORTHWEST WITH CU DEVELOPING SOUTH AND EAST. SHORT RANGE
MODELS CONTINUE TO BRING SOME LIGHT RETURNS INTO THE SOUTH CENTRAL
THIS AFTERNOON. ADDED SOME VERY SMALL POPS...WHICH WILL KEEP THE
MENTION OF SHOWERS OUT OF THE WORDED FORECAST. LATEST 12 UTC NAM
AND 15 UTC RAP SHOW ONLY A SHALLOW LAYER OF MOISTURE AROUND 3-5K
FEET. MADE SOME MINOR CHANGES TO SKY COVER AND TEMPERATURES.
UPDATE ISSUED AT 950 AM CDT WED AUG 27
2014
LATEST SATELLITE SHOWS QUITE A BIT OF FOG REMAINING OVER SOUTHWEST
AND SOUTH CENTRAL NORTH DAKOTA. HOWEVER...LOOKS LIKE IT IS
DISSIPATING QUICKLY THUS WILL LIKELY DROP THE ADVISORY AFTER
TAKING A LOOK AT THE 10 AM OBSERVATIONS. OTHERWISE NO SIGNIFICANT
ISSUES TO THE GOING FORECAST. WILL UPDATE TEXT PRODUCTS WILL BE
SENT WITH THE EXPIRATION/CANCELLATION OF THE DENSE FOG ADVISORY.
UPDATE ISSUED AT 623 AM CDT WED AUG 27 2014
REFINED THE FOG AREAS TO REFLECT FOG OVER MOST OF THE WEST AND
CENTRAL THIS MORNING. LEFT THE ADVISORY AREA IN PLACE.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 431 AM CDT WED AUG 27 2014
FOR THE NEAR TERM/EARLY THIS MORNING...THE CURRENT FOG/STRATUS
IMAGERY LOOP IN COMBINATION WITH SURFACE OBSERVATIONS SHOWS DENSE
FOG EXPANDING OVER MOST OF CENTRAL NORTH DAKOTA. BASED ON CURRENT
VISIBILITY TRENDS AND LATEST HRRR VISIBILITY FORECAST...HAVE
ISSUED A DENSE FOG ADVISORY FOR MOST OF CENTRAL NORTH DAKOTA
THROUGH LATE WEDNESDAY MORNING.
OTHERWISE...A CLEAR SKY DOMINATES WEST AND NORTH WITH THE LATEST
WATER VAPOR IMAGERY SHOWING SUBSIDENCE BEHIND A NORTHERN STREAM
SHORTWAVE NOW INTO MINNESOTA. SPLIT FLOW CONTINUES WITH THE
SOUTHERN BRANCH EXTENDING FROM THE GREAT BASIN INTO SOUTH DAKOTA.
AN UPPER LOW/TROUGH WAS SEEN OVER WESTERN NEVADA EARLY THIS MORNING.
EXPECTING PLENTY OF SUNSHINE TODAY WITH TEMPERATURES WARMING INTO
THE 70S...AND LOWER 80S IN THE FAR WEST. ALL MODEL GUIDANCE...WITH
THE EXCEPTION OF THE GFS...ARE IN AGREEMENT THAT THE SOUTHERN
BRANCH MAKES A RETURN INTO SOUTHERN NORTH DAKOTA WEDNESDAY NIGHT.
AS THE AFOREMENTIONED GREAT BASIN LOW/TROUGH SHIFTS EAST...A
SURFACE LOW WILL TAKE SHAPE OVER NEBRASKA AND SOUTH DAKOTA LATER
TODAY INTO TONIGHT. LATEST TRENDS INDICATE THE NORTHERN FRINGE OF
PRECIPITATION WILL REACH THE JAMES RIVER VALLEY BETWEEN 06Z AND
12Z THURSDAY. AFTER COLLABORATING WITH ABERDEEN AND GRAND
FORKS...HAVE INTRODUCED A SLIGHT CHANCE MENTION FOR SHOWERS AND WILL
LET SUBSEQUENT SHIFTS LOOK AT THE LATEST DATA TO FINE TUNE.
.LONG TERM...(THURSDAY THROUGH TUESDAY)
ISSUED AT 431 AM CDT WED AUG 27 2014
DURING THIS PERIOD THERE WILL BE SEVERAL COLD FRONTAL PASSAGES THAT
WILL BRING SOME ACTIVE WEATHER TO THE REGION OVER THE LABOR DAY
WEEKEND. FIRST...THE REMNANTS OF AN UPPER LEVEL LOW WILL TRACK SOUTH
OF THE STATE THURSDAY. WHILE THIS FEATURE WILL IMPACT THE AREAS
SOUTH OF THE STATE WITH SEVERAL LARGE MCS TYPE CONVECTIVE
SYSTEMS...THERE WILL BE SOME RESIDUAL MOISTURE PULLED INTO THE
STATE...MAINLY ACROSS THE JAMES RIVER VALLEY THURSDAY MORNING. BUT
THERE WILL LIKELY BE MORE CLOUDS THROUGH THE DAY THURSDAY THAN
PREVIOUSLY THOUGHT ACROSS A LARGE PORTION OF SOUTHERN AND EASTERN
NORTH DAKOTA. AFTER THIS A COLD FRONT WILL ENTER THE NORTHWEST
SUPPORTED BY A RATHER WEAK LEADING SHORTWAVE TROUGH AHEAD OF A MORE
SIGNIFICANT SHORTWAVE STILL LINGERING ACROSS THE NORTHWEST US FRIDAY.
OVERALL...HAVE DOWN PLAYED THE POPS THURSDAY NIGHT AND
FRIDAY...WAITING INSTEAD FOR THE MORE SIGNIFICANT SHORTWAVE DUE IN
SATURDAY NIGHT AND SUNDAY. WITH THIS NEXT SYSTEM WILL SEE MORE
SIGNIFICANT PRECIPITATION WITH STRONGER WARM/COLD FRONTAL PASSAGES.
SO THE HOLIDAY WEEKEND SHOULD BE A BIT SOGGY SATURDAY NIGHT WITH
SCATTERED SHOWERS ON SUNDAY. COOL CYCLONIC FLOW ALOFT SHOULD
MAINTAIN SLIGHT THREAT FOR THUNDERSTORMS MONDAY AND TUESDAY.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z THURSDAY AFTERNOON)
ISSUED AT 1258 PM CDT WED AUG 27 2014
SKIES INITIALLY CLEAR AT 17 UTC...BUT CU IS FILLING IN QUICKLY
ACROSS THE SOUTH CENTRAL AND EAST. KDIK...KISN AND KMOT SHOULD BE
VFR THIS AFTERNOON. KBIS-KJMS MAINLY VFR BUT A BRIEF PERIOD OF
MVFR CEILINGS POSSIBLE BEFORE CU FIELD LIFTS ABOVE 3K FEET. THEN
LOW VFR CEILING LATE AFTERNOON AND TONIGHT. SYSTEM BRUSHES THE
SOUTHEAST TONIGHT AND ADDED A VCSH AT KJMS AND KEPT LOW VFR
CEILINGS AT KBIS AND KJMS. LEFT KDIK-KISN-KMOT VFR FOR NOW WITH A
MENTION OF VCFG AROUND 10-14 UTC THURSDAY. WILL NEED TO MONITOR
FOR HITTING FOG HARDER WITH LATER SHIFTS.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...TWH
SHORT TERM...KS
LONG TERM...WAA
AVIATION...TWH
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
428 PM EDT WED AUG 27 2014
.SYNOPSIS...
A COLD FRONT OVER NORTHERN PENNSYLVANIA WILL CLEAR THE SOUTHERN
TIER OF THE STATE EARLY TONIGHT. HIGH PRESSURE WILL ARRIVE BEHIND
THE FRONT AND BRING DRY WEATHER TO THE AREA THROUGH THE END OF THE
WEEK. ABOVE NORMAL TEMPERATURES AND INCREASINGLY HUMID AND
UNSETTLED CONDITIONS ARE FORECAST OVER THE LABOR DAY HOLIDAY
WEEKEND AND INTO THE FIRST WEEK OF SEPTEMBER.
&&
.NEAR TERM /UNTIL 6 AM THURSDAY MORNING/...
FIRST FEW SHRA/TSRA NOW SHOWING UP OVER KPIT/KAGC AND OVER THE
KCCX SITE ITSELF ON TOP OF RATTLESNAKE RIDGE. COVERAGE IS STILL
EXPECTED TO BE RATHER SPARSE BUT THE BACKYARD LOOKS LIKE IT WILL
GET WET SOON. HRRR AND RAP STILL PLACE BIGGER CONCENTRATION OF
SHOWERS THIS EVENING WHERE LLVL CONVERGENCE IS BEST - OVER THE
NERO MTG AND POCONOS...AND IN THE LAURELS. HOWEVER...THE SHOWERS
IN BLACK SHOW THAT THE HOT TEMPS TODAY ARE COOKING UP PLENTY OF
INSTABILITY. THE CAPES COULD BE HEALTHY ENOUGH TO MAKE SOME OF THE
STORMS TAP INTO SOME OF THE 35-40KT WINDS ALOFT. SPIC CONTINUES
TO MENTION AREA IN THE DAY1 OUTLOOK. SO...SOME MARGINAL WIND GUSTS
ARE STILL POSSIBLE...BUT NOT WIDESPREAD. THE COLD FRONT LAGS
BEHIND THE CURRENT CONVECTION AND WILL LIKELY FIRE UP MORE
ISOLD/SCT CONVECTION AS IT MOVES INTO THE MORE-HUMID AIR OVER THE
CENTRAL AND SERN COS. POPS IN THE CHC/SCT CATEGORY FOR ANY ONE
HOUR STILL SEEM LIKE THE BEST APPROACH.
THE FRONT AND DRIER AIR SHOULD ARRIVE IN THE CENTRAL COS AROUND
SUNSET AND MOVE OUT OF THE CWA HEADED SOUTH AROUND MIDNIGHT. SKIES
SHOULD CLEAR OUT NICELY BEHIND THE FRONT AND TEMPS COULD GET INTO
THE 40S IN THE NAN MTG. ALSO...DECOUPLING SHOULD OCCUR IN MOST
PLACES. THUS...YE OLDEN RIVER VALLEY FOG IS EXPECTED THERE. MINS
WILL PROBABLY STAY IN THE L60S IN THE SRN TIER.
&&
.SHORT TERM /6 AM THURSDAY MORNING THROUGH 6 PM THURSDAY/...
COOL POST-FRONTAL NW FLOW WILL MAKE FOR A MOSTLY SUNNY DAY OVER
MOST OF THE REGION. THE ONLY FLY IN THE OINTMENT MIGHT BE THE
APPROACH OF A LOWER CLOUD DECK FROM THE N/NE AS A STRONG PORT MAX
DROPS S ACROSS NY STATE. WILL KEEP POPS UP NEAR ISOLD NUMBERS IN
THE NE...BUT NOT MENTION PRECIP QUITE YET. A SPRINKLE IS POSSIBLE
IN THE NE THOUGH. MAXES WILL BE ABOUT 8-10F BELOW WEDNESDAY/S
LOFTY NUMBERS.
&&
.LONG TERM /THURSDAY NIGHT THROUGH WEDNESDAY/...
THE MEDIUM RANGE FLOW PATTERN WILL FEATURE TROUGHING IN THE WEST
AND FAIRLY HIGH HEIGHTS FCST TO PREVAIL OVER THE EAST SUPPORTED
BY A SUBTROPICAL RIDGE THAT SHOULD ANCHOR OVER THE SOUTHEAST. THIS
RIDGE WILL ALLOW HIGH PRESSURE TO CENTER OVER UPSTATE NY AT THE
START OF THE PERIOD. THIS WILL SLOWLY MOVE OFF THE NEW ENGLAND
COAST ON SATURDAY. A LONG FRONTAL BOUNDARY EXTENDING FROM AN UPPER
LEVEL LOW CENTERED OVER NORTHERN CANADA...AND TO A NEGATIVELY
TILTING TROUGH WHICH SHOULD BE MOVING INTO THE MIDWEST. THE
BIGGEST MOISTURE FROM THE FRONTAL BOUNDARY IS PROGGED TO STAY
NORTH OF PA.
HOWEVER...THERE SHOULD BE ENOUGH MOISTURE...WITH ENOUGH FORCING
TO WARRANT INCREASING PROBABILITY/OPPORTUNITY FOR RAIN SATURDAY
NIGHT INTO EARLY MONDAY. DAYTIME CONVECTION WILL ALSO BE SPURRED
ON BY A WARMING TREND WITH MAX TEMPS 5-10F ABOVE NORMAL OVER THE
WEEKEND AND INTO THE FIRST WEEK OF SEPT. THE BEST CHANCE FOR
PRECIPITATION THROUGH THIS TIMEFRAME SHOULD BE SUNDAY AFTERNOON
INTO SUNDAY EVENING. THERE IS SOME MODEL VARIATION SO EXPECT SOME
MODIFICATIONS AS TIME PROGRESSES. A GFS AND EC IN THE LONG RANGE
ARE ACTUALLY IN FAIR AGREEMENT THROUGH THE FIRST HALF OF NEXT
WEEK...INCLUDING THE SUBSTANTIAL TROUGH THAT SHOULD MOVE THROUGH
WEDNESDAY AS MORE DEFINED COLD FRONT SHOULD APPROACHES THE AREA.
&&
.AVIATION /20Z WEDNESDAY THROUGH MONDAY/...
COLD FRONT APPEARS TO BE JUST THROUGH KBFD AT 18Z. ONE BATCH OF
TSRA OVER KAGC IS HEADED SOUTH OF KJST. ALL BUT KBFD WILL
CONTINUE TO HAVE THE POSSIBILITY FOR TSRA IN THE VCTY...BUT HAVE
ONLY INCLUDED VCSH/TS FOR NOW DUE TO SPARSE COVERAGE. THIS THREAT
SHOULD END AROUND 23Z-00Z IN IPT/UNV BUT COULD LINGER UNTIL 03Z IN
THE SRN TERMINALS. WIND SHIFT TO THE NW BEHIND THE FRONT WILL
BRING DRIER AND COOLER AIR. NORMAL VALLEY FOG IS EXPECTED IN THE
NRN VALLEYS AS THE TEMPS DROP OFF WELL BELOW THE RIVER WATER
TEMPS. BUT THERE COULD BE A LITTLE WIND WHICH COULD IMPEDE FOG
FORMATION. WILL PUT MVFR FOG IN MOST TAFS AND IFR FOG IN BFD FOR A
FEW HRS LATE TONIGHT. THE NW WINDS PICK UP AFTER SUNRISE BUT SKIES
AND VIS SHOULD BE VFR. A LOW-END VFR CLOUD DECK MAY DROP DOWN
FROM WRN NY STATE DURING THE DAYLIGHT HRS ON THURS.
OUTLOOK...
FRI-SAT...EARLY MORNING FOG RESTRICTIONS POSSIBLE...OTHERWISE
VFR.
SUN-MON...MAINLY VFR. SCT AFTERNOON SHOWERS/TSTMS.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...DANGELO
NEAR TERM...DANGELO
SHORT TERM...DANGELO
LONG TERM...CERU/STEINBUGL
AVIATION...DANGELO
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
256 PM EDT WED AUG 27 2014
.SYNOPSIS...
A COLD FRONT OVER NORTHERN PENNSYLVANIA WILL CLEAR THE SOUTHERN
TIER OF THE STATE EARLY TONIGHT. HIGH PRESSURE WILL ARRIVE BEHIND
THE FRONT AND BRING DRY WEATHER TO THE AREA THROUGH THE END OF THE
WEEK. ABOVE NORMAL TEMPERATURES AND INCREASINGLY HUMID AND
UNSETTLED CONDITIONS ARE FORECAST OVER THE LABOR DAY HOLIDAY
WEEKEND AND INTO THE FIRST WEEK OF SEPTEMBER.
&&
.NEAR TERM /THROUGH TONIGHT/...
FIRST FEW SHRA/TSRA NOW SHOWING UP OVER KPIT/KAGC AND OVER THE
KCCX SITE ITSELF ON TOP OF RATTLESNAKE RIDGE. COVERAGE IS STILL
EXPECTED TO BE RATHER SPARSE BUT THE BACKYARD LOOKS LIKE IT WILL
GET WET SOON. HRRR AND RAP STILL PLACE BIGGER CONCENTRATION OF
SHOWERS THIS EVENING WHERE LLVL CONVERGENCE IS BEST - OVER THE
NERO MTG AND POCONOS...AND IN THE LAURELS. HOWEVER...THE SHOWERS
IN BLACK SHOW THAT THE HOT TEMPS TODAY ARE COOKING UP PLENTY OF
INSTABILITY. THE CAPES COULD BE HEALTHY ENOUGH TO MAKE SOME OF THE
STORMS TAP INTO SOME OF THE 35-40KT WINDS ALOFT. SPIC CONTINUES
TO MENTION AREA IN THE DAY1 OUTLOOK. SO...SOME MARGINAL WIND GUSTS
ARE STILL POSSIBLE...BUT NOT WIDESPREAD. THE COLD FRONT LAGS
BEHIND THE CURRENT CONVECTION AND WILL LIKELY FIRE UP MORE
ISOLD/SCT CONVECTION AS IT MOVES INTO THE MORE-HUMID AIR OVER THE
CENTRAL AND SERN COS. POPS IN THE CHC/SCT CATEGORY FOR ANY ONE
HOUR STILL SEEM LIKE THE BEST APPROACH.
THE FRONT AND DRIER AIR SHOULD ARRIVE IN THE CENTRAL COS AROUND
SUNSET AND MOVE OUT OF THE CWA HEADED SOUTH AROUND MIDNIGHT. SKIES
SHOULD CLEAR OUT NICELY BEHIND THE FRONT AND TEMPS COULD GET INTO
THE 40S IN THE NAN MTG. ALSO...DECOUPLING SHOULD OCCUR IN MOST
PLACES. THUS...YE OLDEN RIVER VALLEY FOG IS EXPECTED THERE. MINS
WILL PROBABLY STAY IN THE L60S IN THE SRN TIER.
&&
.SHORT TERM /THURSDAY/...
COOL POST-FRONTAL NW FLOW WILL MAKE FOR A MOSTLY SUNNY DAY OVER
MOST OF THE REGION. THE ONLY FLY IN THE OINTMENT MIGHT BE THE
APPROACH OF A LOWER CLOUD DECK FROM THE N/NE AS A STRONG PORT MAX
DROPS S ACROSS NY STATE. WILL KEEP POPS UP NEAR ISOLD NUMBERS IN
THE NE...BUT NOT MENTION PRECIP QUITE YET. A SPRINKLE IS POSSIBLE
IN THE NE THOUGH. MAXES WILL BE ABOUT 8-10F BELOW WEDNESDAY/S
LOFTY NUMBERS.
&&
.LONG TERM /THURSDAY NIGHT THROUGH WEDNESDAY/...
MEDIUM RANGE FLOW PATTERN ACTS THE ONUS WILL FEATURE DROVING IN
THE WEST AND FAIRLY HIGH HEIGHTS FCST TO PREVAIL OVER THE EAST
(FOR A CHANGE) SUPPORTED BY SUBTROPICAL RIDGE ANCHORED OVER THE
SOUTHEAST. HIGH PRESSURE CENTERED OVER UPSTATE NY AT THE START OF
THE PERIOD WILL MOVE OFF THE NAN NEW ENGLAND COAST ON SATURDAY AS
TODAYS FRONTAL BOUNDARY PIVOTS BACK NOD AS A WARM FRONT...IN
RESPONSE TO SHORTWAVE/SFC WAVE FCST TO TRACK NEED FROM THE ERN
PLAINS/MS CLY. OVER THE PAST 12-24 HOURS THE LATEST GUIDANCE HAS
TRENDED NOD WITH SFC LOW TRACKS THRU THE GREAT LAKES AROUND
D4/SUN AND WITH LEADING FRONTAL BOUNDARY WHICH IS NOW PROGGED BY
WP TO STAY NORTH OF PA. A MORE DEFINED COLD FRONT SHOULD APPROACH
THE AREA BY THE MIDDLE OF NEXT WEEK.
A RATHER MOIST RETURN FLOW AROUND SOUTHEAST RIDGE AND AHEAD MID
LVL SHORTWAVE TRACKING NEWD FROM THE ERN PLAINS/MS VLY ALONG WITH
INTERACTION WITH ASSOCIATED SFC WAVE/WAVY LEADING FRONTAL ZONE
SHOULD SPELL AN INCREASING PROBABILITY/OPPORTUNITY FOR RAIN INTO
THE WEEKEND. HOWEVER CONFIDENCE IN PCPN DETAILS (I.E. POPS) IS
MEDIUM AT BEST DUE TO MODEL SPREAD/DEPENDENCE ON SMALLER SCALE
FEATURES. THE FCST MAY BE PERCEIVED AS SOMEWHAT PESSIMISTIC WITH
NEARLY DAILY CHC FOR SHWRS/TSTMS HOWEVER PCPN WILL CERTAINLY NOT
BE CONTINUOUS WITH PERIODS OF DRY WX MIXED IN BTWN GENERALLY SCT
AND LARGELY DISORGANIZED/WEAKLY FORCED PCPN.
THERE IS HIGHER CONFIDENCE IN A WARMING TREND WITH MAX TEMPS 5-10F
ABOVE NORMAL OVER THE WEEKEND AND INTO THE FIRST WEEK OF SEPT.
&&
.AVIATION /19Z WEDNESDAY THROUGH MONDAY/...
COLD FRONT APPEARS TO BE JUST THROUGH KBFD AT 18Z. ONE BATCH OF
TSRA OVER KAGC IS HEADED SOUTH OF KJST. ALL BUT KBFD WILL
CONTINUE TO HAVE THE POSSIBILITY FOR TSRA IN THE VCTY...BUT HAVE
ONLY INCLUDED VCSH/TS FOR NOW DUE TO SPARSE COVERAGE. THIS THREAT
SHOULD END AROUND 23Z-00Z IN IPT/UNV BUT COULD LINGER UNTIL 03Z IN
THE SRN TERMINALS. WIND SHIFT TO THE NW BEHIND THE FRONT WILL
BRING DRIER AND COOLER AIR. NORMAL VALLEY FOG IS EXPECTED IN THE
NRN VALLEYS AS THE TEMPS DROP OFF WELL BELOW THE RIVER WATER
TEMPS. BUT THERE COULD BE A LITTLE WIND WHICH COULD IMPEDE FOG
FORMATION. WILL PUT MVFR FOG IN MOST TAFS AND IFR FOG IN BFD FOR A
FEW HRS LATE TONIGHT. THE NW WINDS PICK UP AFTER SUNRISE BUT SKIES
AND VIS SHOULD BE VFR. A LOW-END VFR CLOUD DECK MAY DROP DOWN
FROM WRN NY STATE DURING THE DAYLIGHT HRS ON THURS.
OUTLOOK...
FRI-SAT...EARLY MORNING FOG RESTRICTIONS POSSIBLE...OTHERWISE
VFR.
SUN-MON...MAINLY VFR. SCT AFTERNOON SHOWERS/TSTMS.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...DANGELO
NEAR TERM...DANGELO
SHORT TERM...DANGELO
LONG TERM...STEINBUGL
AVIATION...DANGELO
AREA FORECAST DISCUSSION FOR WESTERN SD AND NORTHEASTERN WY
NWS RAPID CITY SD
1012 AM MDT WED AUG 27 2014
.UPDATE...
ISSUED AT 1012 AM MDT WED AUG 27 2014
CURRENT SURFACE ANALYSIS SHOWS LOW PRESSURE OVER FAR NORTHEAST
CO...WITH A NEARLY STATIONARY FRONTAL BOUNDARY FROM WESTERN WY TO
NORTHEAST KS. UPPER LEVEL ANALYSIS SHOWS LOW PRESSURE OVER EASTERN
UT...WITH TROF COVERING THE ROCKIES AND MUCH OF THE HIGH PLAINS.
SKIES ARE VARIABLY CLOUDY ACROSS THE AREA...WITH AREAS OF FOG
LIFTING OVER EASTERN PORTIONS OF THE CWA. REGIONAL RADARS SHOW
MOST OF THE SHOWER AND THUNDERSTORM ACTIVITY IN TWO AREAS. THE
MAIN AREA IS OVER SOUTHERN AND CENTRAL WY...MOVING NORTH-
NORTHWESTWARD AROUND THE UPPER LOW. ANOTHER AREA OF LIGHTER
ACTIVITY IS LOCATED OVER CENTRAL NEB INTO PORTIONS OF SOUTHEAST
SD...MOVING NORTH-NORTHEAST. OUR AREA IS DRY AT THE MOMENT...BUT
SHOWERS AND STORMS WILL MOVE IN FROM THE SOUTH AND ALSO DEVELOP
AS THE UPPER LOW MOVES ACROSS SOUTHERN WY/NORTHERN CO THIS
AFTERNOON AND EVENING...ESPECIALLY OVER THE BLACK HILLS AND
SOUTHERN PORTIONS OF THE CWA. THERE SHOULD BE A FAIRLY SHARP
CUT-OFF TO THE COVERAGE OF SHOWERS... LIKELY SOMEWHERE NEAR OR
JUST NORTH OF THE I-90 CORRIDOR. THE THREAT FOR SEVERE STORMS
REMAINS LOW WITH MAIN AREA OF INSTABILITY STAYING SOUTH OF THE
AREA.
HAVE MADE A MINOR UPDATE TO THE FORECAST...MAINLY TO LOWER POPS
ACROSS THE AREA THIS MORNING AND RAISE THEM OVER THE BLACK HILLS
THIS AFTERNOON. ALSO MADE SOME ADJUSTMENTS TO CLOUD COVER FOR THE
NEXT FEW HOURS. TEMP FORECAST FOR TODAY LOOKS GOOD AT THE MOMENT...
BUT MAY HAVE TO TWEAK THEM A BIT LATER ON...DEPENDING ON CLOUD
AND SHOWER COVERAGE.
&&
.SHORT TERM...TODAY THROUGH THURSDAY NIGHT
ISSUED AT 251 AM MDT WED AUG 27 2014
LATEST WATER VAPOR IMAGERY SHOWS AN AREA OF LOW PRESSURE OVER
NEVADA/UTAH WITH A NORTHERN STREAM TROUGH EXTENDING FROM CENTRAL
CANADA INTO THE NORTHERN PLAINS. THE NORTHERN STREAM TROF WILL
QUICKLY MOVE EASTWARD AS THE CUTOFF LOW SLOWLY PROPAGATES INTO THE
CENTRAL ROCKIES. SOUTHWESTERLY FLOW CONTINUES OVER THE
CENTRAL/NORTHERN PLAINS.
FOR TODAY THE BEST FORCING REMAINS SOUTH OF THE CWA. BEST CHANCES
OF PRECIP THROUGH THURSDAY WILL BE ACROSS THE FAR SOUTHERN PORTIONS
OF THE FORECAST AREA AS A SERIES OF WAVES CROSS THE COLORADO/NEBRASKA
AREA. MODELS ARE VARYING WITH TIMING OF WAVES AND HOW FAR NORTH
THE PRECIP WILL EXTEND WITHIN THE CWA. EITHER WAY QPF AMOUNTS WILL
BE LIMITED...EXCEPT WITH THE POSSIBILITY OF SOME STRONGER STORMS
CROSSING AREAS NEAR THE NEBRASKA BORDER. HIGH TEMPERATURES TODAY
WILL ONCE AGAIN BE BELOW AVERAGE DUE TO CLOUD COVER. AS THE UPPER
LOW MOVES THROUGH NEBRASKA/KANSAS...PRECIP CHANCES WILL DIMINISH
ACROSS THE AREA WITH DRY CONDITIONS BY THURSDAY AFTERNOON/EVENING.
&&
.LONG TERM...FRIDAY THROUGH TUESDAY
ISSUED AT 251 AM MDT WED AUG 27 2014
PROGRESSIVE NORTHERN STREAM FLOW WILL CONTINUE THROUGH THE
PERIOD. TWO MAIN SYSTEMS EXPECTED TO AFFECT THE REGION IN THE
PERIOD...A WEAK NORTHERN STREAM TROUGH FRIDAY...AND A MORE ROBUST
LONGWAVE UPPER TROUGH SAT NIGHT INTO MONDAY. FORECAST MODELS IN
GOOD AGREEMENT PER WAVE AMPLITUDE AND TRACK. HOWEVER...SOME
SUBSTANTIAL DIFFERENCES BEGIN TO EMERGE IN THE SUNDAY NIGHT INTO
MONDAY PERIOD BETWEEN THE ECMWF AND GFS...MAINLY THE HANDLING OF
THE NW CONUS SOUTHERN PERIPHERY EJECTING IMPULSE. THE ECMWF HAS A
SOUTHERN BIAS TO THE SYSTEM WITH THE BULK OF LSA PASSING THROUGH
THE FA AS OPPOSED TO A MORE NORTHERN TRACK IN THE GFS...WHICH IS
ALSO FASTER. THE ECMWF SOLUTION WOULD SUPPORT BETTER CHANCES FOR
RAIN IN THE FA HOWEVER MOISTURE LIMITATIONS MAY PRECLUDE ANY
PRECIP TOTALS THEN.
RETAINED PREV POPS FOR FRIDAY AFTERNOON...WITH A SLIGHT UPTICK AND
EXPANSION OF SLIGHT MENTION. FORECAST MODELS CONTINUE TO INDICATE A
SFC TROUGH STALLING ACROSS THE SW HALF FRIDAY...WITH A PASSING UPPER
LEVEL IMPULSE. SUFFICIENT LL MOISTURE ND RESULTING CAPE WOULD BE
CONDUCIVE FOR CONVECTION IN THE AFTERNOON...ESP OVER THE BLACK
HILLS. OTHERWISE...A MORE IMPRESSIVE UPPER LEVEL TROUGH WILL PUSH
OUT OF THE NE PAC AND INTO THE NORTHERN PLAINS...SUPPORTING
INCREASING LSA SAT NIGHT THROUGH SUNDAY NIGHT. BETTER SFC CYCLONE
DEVELOPMENT LOOKS TO REMAIN WELL EAST OF THE REGION...SUPPORTING
MORE ELEVATED/CONVECTIVE CHANCES BEHIND THE SFC TROUGH RATHER THAN
WIDESPREAD DEFORMATION RAINS. HENCE...KEPT POPS IN THE SLIGHT TO
LOW CHANCE CAT FOR NOW...ESP AS DEEPER MOISTURE WILL SHIFT QUICKLY
EAST OUT OF THE REGION. KEPT MOST OF THE REGION DRY MONDAY THROUGH
TUES...WITH UPPER LEVEL RIDGING COMMENCING AND DRY PROFILES.
SEASONAL TEMPS EXPECTED IN MOST OF THE PERIOD...WITH BELOW NORMAL
TEMPS /5-10 DEGREES/ EXPECTED MONDAY AND PERHAPS TUES BEHIND
SUNDAY/S COLD FRONT...ESP NW AREAS.
&&
.AVIATION...FOR THE 12Z TAFS THROUGH 12Z WEDNESDAY NIGHT
ISSUED AT 251 AM MDT WED AUG 27 2014
SCT-ISOLD SHOWERS/THUNDERSTORMS EXPECTED ACROSS THE SOUTHERN HALF
THROUGH MOST OF THE PERIOD AS A SERIES OF IMPULSES CROSS THE
REGION. LCL MVFR/IFR CONDS EXP WITH HEAVIER PRECIPITATION.
ADDITIONALLY...IFR CIGS WILL SPREAD NORTH ACROSS SW AND SCENTRAL
SD THIS MORNING...WITH CIGS TRENDING TO MVFR LATE MORNING/EARLY
AFTERNOON. CIGS MAY LINGER THROUGH THE PERIOD THERE. WINDS WILL
VEER SE AROUND KRAP THIS AFTERNOON...WITH THE POTENTIAL FOR MVFR
CIGS TO SPREAD INTO THE RAP TERMINAL THEN. HAVE HINTED AT THIS IN
THE TAF.
&&
.UNR WATCHES/WARNINGS/ADVISORIES...
SD...NONE.
WY...NONE.
&&
$$
UPDATE...26
SHORT TERM...MLS
LONG TERM...JC
AVIATION...JC
AREA FORECAST DISCUSSION
NWS NASHVILLE TN
203 PM CDT WED AUG 27 2014
.UPDATE...
18Z TAF DISCUSSION.
&&
.AVIATION...
ISO -SHRA WILL DEVELOP NEAR CKV THIS AFTERNOON. OTHERWISE...VFR
CONDITIONS ARE ANTICIPATED AT AIRPORTS THROUGH THIS EVENING BEFORE
FOG BRINGS MVFR/IFR VIS TO CKV/CSV AFTER MIDNIGHT. LIGHT NORTHEAST
WINDS ARE ANTICIPATED THROUGHOUT THE TAF PERIOD.
SHAMBURGER
&&
.PREV DISCUSSION... /ISSUED 1016 AM CDT WED AUG 27 2014/
UPDATE...
LATEST VISIBLE SATELLITE IMAGERY SHOWS MOSTLY CLEAR SKIES WITH
CUMULUS DEVELOPMENT UNDERWAY ACROSS CENTRAL PARTS OF THE MID STATE
AND THE PLATEAU ALONG WITH SOME CIRRUS MOVING ACROSS. TEMPERATURES
RISING QUICKLY AND CURRENTLY IN THE UPPER 70S EAST TO MID 80S
ELSEWHERE. DEWPOINT CURRENTLY IN THE MID 60S TO MID 70S WILL MIX
OUT SOME OVER EASTERN HALF OF THE AREA THIS AFTERNOON...BUT STILL
ANTICIPATING A HOT AND HUMID DAY ON TAP FOR MOST LOCATIONS AND NO
CHANGES WERE MADE TO TEMPS. STILL CANNOT RULE OUT AN ISOLATED
SHOWER OR STORM OVER NORTHWEST ZONES WHERE DEEPER MOISTURE IS
PRESENT...AND ADJUSTED POPS SOMEWHAT BASED ON THE LATEST HRRR
MODEL.
SHAMBURGER
PREV DISCUSSION... /ISSUED 526 AM CDT WED AUG 27 2014/
UPDATE...FOR 12Z TAFS.
AVIATION...
MORELESS A REPEAT OF THE PAST FEW DAYS WITH CONVECTION TODAY
MAINLY ACROSS THE NORTHWEST. EARLY MORNING FOG EXPECTED TO CLEAR
14-15Z LEAVING VFR CONDITIONS THROUGHOUT THE DAY AND INTO THE
EVENING. FOG IS EXPECTED TO REDEVELOP LATE EVENING CSV...THEN
AGAIN OVERNIGHT CKV/BNA. CONDITIONS LIKELY TO DROP BRIEFLY TO
IFR CSV/CKV 06-13Z THU.
PREV DISCUSSION... /ISSUED 345 AM CDT WED AUG 27 2014
UPPER RIDGING IN CONTROL ACROSS THE SOUTHEASTERN U.S.. AT THE
SFC...HIGH PRESSURE IS LOCATED OVER THE GREAT LAKES REGION. THIS
FEATURE IS LARGE ENOUGH TO CONTROL OUR WEATHER AND A LIGHT NE FLOW
IS EXPECTED TODAY. ON THURSDAY...THE UPPER HIGH WILL BUILD SE TOWARD
NRN FL WITH A RIDGE AXIS EXTENDING NW ACROSS TN. ALL OF THIS RIDGING
WILL ACT TO IMPEDE ANY LOW LEVEL BOUNDARY INFLUENCE. CONVECTIVE
PARAMETERS SHOW VERY LITTLE CHANCE OF CONVECTION FOR TODAY. BUT...WE
DO SEE AN INCREASE IN CAPE VALUES ON THU AFTERNOON...BUT THIS IS
ACROSS THE NORTH ONLY. SO...WILL INCLUDE A SLIGHT CHANCE OF AFT
SHOWERS AND TSTMS. FURTHERMORE...THE HRRR IS SHOWING SOME AFT
DEVELOPMENT ACROSS THE KY AREA THIS AFTERNOON. MID/UPPER LEVEL
FLOW PATTERN DICTATES THAT THIS ACTIVITY WILL MOVE SE.
THEREFORE...MAY NEED TO INCLUDE A SLIGHT CHANCE OF AFT SHOWERS AND
TSTMS ACROSS THE NORTH FOR TODAY AS WELL. WILL LEAN TOWARD ISC AND
CURRENT GRIDS FOR A FINAL DECISION.
FOR THE NEAR TERM TEMPS...ABOVE NORMAL TEMPS EXPECTED WITH HIGHS
GENERALLY IN THE LOWER 90S...LOWS LOWER 70S...COOLER PLATEAU.
IN THE EXT FCST...SHORTWAVE TO DEVELOP OVER THE NATIONS INTERIOR
THIS WEEKEND. WIND FLOW PATTERN WILL THEN EVOLVE INTO A MORE UNIFORM
SOUTHERLY FLOW WHICH WILL BRING INCREASING MOISTURE LEVELS BACK
ACROSS THE AREA. THOUGH THE SHORTWAVE WILL LIFT OFF TO THE NE AND
NOT DIRECTLY IMPACT THE MID STATE...CONVECTIVE CONDITIONS WILL
BECOME MORE FAVORABLE. THE GFS ACTUALLY EMPHASIZES AN UPSTREAM
IMPULSE IN CLOSE PROXIMITY FOR SAT NT. SO...ALL IN ALL... POPS
WILL BE ON THE INCREASE FOR THE SAT THROUGH MON PERIOD.
THEREAFTER...W-E UPPER RIDGING WILL REDEVELOP ACROSS THE DEEP
SOUTH WITH POPS ON THE DOWNSWING.
FOR THE EXT TEMPS...ABOVE NORMAL VALUES TO CONTINUE EVEN THOUGH
RIDGING BACKS OFF DURING THE SAT THROUGH MON PERIOD. HEIGHTS
REMAIN ON THE ELEVATED SIDE.
21
&&
.OHX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
55
AREA FORECAST DISCUSSION
NWS LUBBOCK TX
321 PM CDT WED AUG 27 2014
.SHORT TERM...
WV SHOWS THE UPPER LEVEL LOW OF INTEREST CURRENTLY POSITIONED OVER
UT WITH EASTERN NM/WESTERN TX SITTING UNDER A PLUME OF MONSOONAL
MOISTURE THAT IS BEING SUCKED INTO THE LOW. A FEW SHORTWAVES MAKING
THEIR WAY ACROSS NM ARE NOTICED AHEAD OF THE MAIN LOW. THESE
SHORTWAVES WILL TRIGGER OUR FIRST ROUND OF PRECIP LATER TONIGHT.
POPS THROUGH TOMORROW MORNING REMAIN MOSTLY UNCHANGED WITH THE
EXCEPTION OF CHANCE MENTION HAVING BEEN EXPANDED SLIGHTLY EASTWARD.
WHILE THE MAIN SOURCE OF LIFT WILL BE TO OUR WEST...UPPER LEVEL FLOW
OVERHEAD WILL REMAIN SLIGHTLY DIFFLUENT. AS HAS BEEN SEEN THE PAST
SEVERAL DAYS...IT DOES NOT TAKE MUCH LIFT TO FIRE SHALLOW CONVECTION.
ONE NOTE OF INTEREST IS THE 15Z HRRR DEVELOPING A LINE SHALLOW
CONVECTION ALONG THE EDGE OF THE CAPROCK THIS AFTERNOON WHERE WEAK
SURFACE CONVERGENCE IS OBSERVED. CHANCES WILL INCREASE AFTER 12Z
TOMORROW MORNING AS AN UPPER LEVEL JET BEGINS TO FORM JUST TO OUR
NORTHEAST PUTTING A MAJORITY OF OUR EASTERN ZONES IN THE ENTRANCE
REGION OF THE JET HELPING PROMOTE DIVERGENCE. DUE TO INCREASING
DIVERGENCE THROUGH THE AFTERNOON COUPLED WITH PWATS APPROACHING 2
INCHES SUB-LIKELY POPS HAVE BEEN INSERTED ACROSS MUCH OF THE ROLLING
PLAINS. ONE ISSUE THAT WILL NEED TO BE WATCHED IS THE POSSIBILITY OF
LOCALIZED FLOODING DUE TO TRAINING THUNDERSTORMS.
THE SURFACE FRONT WILL APPROACH OUR NORTHWESTERN ZONES EARLY
TOMORROW MORNING BUT SHOULD NOT MAKE IT FAR INTO THE FA WITH THE
FARTHEST EXTENT BEING ALONG A LINE FROM DIMMIT TO BROWNFIELD. CAA
WILL BE RATHER WEAK WITH THIS FRONT WITH TEMPS MODERATING ONLY A FEW
DEGREES FROM WHAT WE WILL SEE TODAY. HIGHS ACROSS THE WESTERN SOUTH
PLAINS AND SOUTHWESTERN TX PANHANDLE SHOULD BE IN THE UPPER 80S/LOW
90S. WITH THE FRONT BEING WEAK COMPRESSIONAL HEATING SHOULD NOT BE
TOO HUGE OF AN ISSUE WHICH WILL PREVENT HIGHS FROM MELTING THE
PAVEMENT OFF OF ROADS.
&&
.LONG TERM...
THE UA TROUGH NOTED ACROSS NERN UTAH LATE THIS AFTN...IS PROGGED
TO CONTINUE TO PROGRESS EWRD TO ACROSS THE CNTRL/SRN PLAINS BY
TOMORROW NIGHT. A PERSISTENT UPSLOPE SFC REGIME WILL ALLOW FOR
PWATS TO INCREASE ON THE ORDER OF 1.25-1.70 INCHES ACROSS THE FA
WHICH COUPLED WITH INCREASED LARGE SCALE ASCENT...WILL AID IN
CONTINUED CHANCES FOR SHOWER AND THUNDERSTORM DEVELOPMENT TOMORROW
NIGHT. FURTHERMORE...A COLD FRONT ASSOCIATED WITH THE
AFOREMENTIONED UA TROUGH MAY IMPINGE ON THE FAR SRN TX
PANHANDLE...NRN SOUTH PLAINS AND NRN ROLLING PLAINS DURING THE DAY
FRIDAY AS HINTED AT BY MODEL SOLUTIONS...WHICH COULD AID IN
CONTINUAL PRECIP CHANCES. HOWEVER...UL SUPPORT WILL COMMENCE TO
DECLINE AS THE UA TROUGH EXITS EAST OF THE REGION BY FRIDAY AFTN.
NONETHELESS...THE PRESENCE OF THE FRONT IS ENOUGH TO MAINTAIN
MENTIONABLE POPS FRIDAY...WITH HIGHEST POPS ACROSS THE ROLLING
PLAINS NEAREST TO THE DEPARTING LARGE SCALE ASCENT. THE POTENTIAL
FOR STORMS TO BECOME SEVERE APPEARS LOW AS A BIT OF A VEERING WIND
PROFILE LACKS SIGNIFICANT WIND SPEEDS ALOFT...HOWEVER LOCALIZED
FLOODING CAN NOT BE RULED DUE TO THE ANTICIPATED ABOVE NORMAL
PWATS.
BY SATURDAY...RATHER LOW AMPLITUDE RIDGING WILL PROGRESS EWRD ACROSS
THE CNTRL CONUS...THOUGH IT IS INTERESTING TO NOTE THAT MODEL
SOLUTIONS DISPLAY LIGHT QPF SIGNALS ACROSS THE CWA. WITH THE
PREVIOUSLY MENTIONED COLD FRONT WASHED OUT/RETREATED NORTH...THE
LIGHT PRECIP APPEARS TO BE CAUSED BY AN EMBEDDED IMPULSE IN THE
FLOW ALOFT. WILL GO AHEAD AND INSERT 10-14 POPS FOR NOW. A NEARBY
SFC TROUGH WILL PROMOTE BREEZY SRLY SFC WINDS FOR THE
WEEKEND...WHILST A BROAD UA LOW AFFECTING SRN CANADA/NORTHERN
ROCKIES WILL CAUSE FLOW ALOFT TO BECOME ZONAL ACROSS THE SRN
PLAINS. AS THE SAID UA SYSTEM TRANSLATES EAST ACROSS THE NRN
PLAINS...IT WILL PUSH A BACKDOOR COLD FRONT TO ACROSS THE FAR SERN
TX PANHANDLE MONDAY...WHICH COULD SERVE AS A PRECIP FOCUS. WILL
HOLD ON TO SILENT POPS BEYOND FRIDAY ATTM...THOUGH WILL NEED TO
KEEP AN EYE ON LATER MODEL RUNS AND SEE IF THIS TRENDS HOLDS FOR
NEXT WEEK.
WITH THE ANTICIPATED RAINFALL AND INCREASED CLOUDINESS EXPECTED
EARLY IN THE EXTENDED PERIOD...TEMPS WILL COOL INTO THE UPPER
80S-LOWER 90S ON FRIDAY. TEMPS WILL QUICKLY REBOUND BACK INTO THE
90S BY THE WEEKEND...AND POSSIBLY NEAR LOWER TRIPLE DIGITS OFF
THE CAPROCK BY EARLY NEXT WEEK.
&&
.PRELIMINARY POINT TEMPS/POPS...
FRIONA 62 88 59 86 60 / 40 30 30 20 20
TULIA 66 88 62 86 63 / 40 40 40 30 20
PLAINVIEW 66 89 63 87 64 / 30 40 40 20 20
LEVELLAND 66 91 64 88 64 / 30 40 40 20 20
LUBBOCK 69 91 67 91 67 / 30 40 40 30 20
DENVER CITY 66 93 65 90 65 / 30 40 40 20 20
BROWNFIELD 67 93 65 90 65 / 30 40 40 20 20
CHILDRESS 73 92 69 90 70 / 30 50 50 30 30
SPUR 68 94 66 91 67 / 20 50 50 30 30
ASPERMONT 72 97 70 94 70 / 20 50 50 30 30
&&
.LUB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
51/29
AREA FORECAST DISCUSSION...UPDATED
NWS FORT WORTH TX
1225 PM CDT WED AUG 27 2014
.AVIATION...
/18Z TAFS/
ISOLATED SHOWERS AND THUNDERSTORMS ARE EXPECTED TO DEVELOP WITHIN
AN AXIS OF MOISTURE EITHER SIDE OF THE I-35 CORRIDOR BETWEEN 18Z
AND 20Z THIS AFTERNOON. MOISTURE IS A LITTLE RICHER NEAR WACO
FROM GOES SOUNDER ANALYSIS AND CORRELATES WELL BEING CLOSER TO
THE LOW PRESSURE SYSTEM OFFSHORE FROM KCRP.
ONLY CHANGE ON THIS FORECAST WILL BE TO INCLUDED VCSH AT WACO
THROUGH EARLY EVENING. OTHERWISE...WILL PLAY THE WAITING GAME FOR
ANY AMENDMENTS REGARDING ISOLATED CONVECTIVE ACTIVITY AND THE DFW
METRO AREA WHERE CONFIDENCE IS NOT QUITE AS HIGH.
EAST WINDS WILL RANGE BETWEEN 6-10 KTS THIS AFTERNOON. WINDS WILL
BECOME SOUTH OR SOUTH-SOUTHEAST NEAR 10 KTS LATER ON THURSDAY
MORNING.
05/
&&
.UPDATE...
TODAY WILL BE A WARM DAY WITH ISOLATED SHOWERS AND THUNDERSTORMS
ACROSS THE REGION THROUGH THE EARLY EVENING HOURS. TEMPERATURES
TODAY WILL BE VERY SIMILAR TO YESTERDAYS HIGH TEMPERATURES. THE
12Z FWD SOUNDING THIS MORNING MEASURED A PWAT OF 1.66
INCHES...INDICATIVE OF DECENT MOISTURE ACROSS THE REGION.
HOWEVER...UNDER THE INFLUENCE OF EASTERLY FLOW FROM THE SURFACE TO
MID LEVELS OF THE ATMOSPHERE...BOTH THE NAM AND RAP INDICATE DRIER
AIR WILL MOVE INTO THE REGION THIS AFTERNOON FROM THE EAST. THIS
TREND IS SUPPORTIVE BY THE GOES PW SOUNDER WHICH INDICATES DRIER
AIR IS CURRENTLY TO OUR EAST. THE NAM AND RAP INDICATE THE DRIEST
AIR...WITH PWATS CLOSER TO 1-1.25 INCHES...WILL MOVE ACROSS OUR
SOUTHEAST COUNTIES THIS AFTERNOON AND CONTINUE A WESTWARD TRACK
THIS EVENING AND TONIGHT.
WHILE DRIER AIR MAY ARRIVE IN OUR EASTERN AND SOUTHEASTERN
COUNTIES LATER TODAY...THE REST OF THE REGION WILL REMAIN MOIST
AND HUMID. SINCE THE RIDGE HAS BEEN WEAKENED...EXPECT ISOLATED
CONVECTION TO OCCUR TODAY AND HAVE EXPANDED THE MENTION OF
ISOLATED SHOWERS/STORMS ACROSS ALL OF NORTH AND CENTRAL TEXAS. IT
WILL BE MORE DIFFICULT FOR CONVECTION TO DEVELOP IN OUR SOUTHEAST
ZONES WHEN THE DRIER AIR ARRIVES LATER BUT UNTIL THEN THERE IS
STILL A CHANCE FOR ISOLATED ACTIVITY. GUSTY WINDS AND BRIEF HEAVY
RAINFALL WILL OCCUR WITH ANY CONVECTION THIS AFTERNOON.
82/JLD
&&
.PREV DISCUSSION... /ISSUED 324 AM CDT WED AUG 27 2014/
A WEAK TUTT WAS LOCATED JUST EAST OF CORPUS CHRISTI THIS MORNING
AND HAS RESULTED IN AN INCREASE IN PWATS AND INSTABILITY ACROSS
THE REGION. ISOLATED SHOWERS/THUNDERSTORMS ARE POSSIBLE OVER THE
WESTERN AND SOUTHERN COUNTIES THIS AFTERNOON AND EVENING.
UPSTREAM...UPPER TROUGH OVER THE GREAT BASIN WILL MOVE OUT OF THE
CENTRAL ROCKIES ON THURSDAY NIGHT AND ACROSS THE GREAT PLAINS BY
LATE FRIDAY NIGHT. SHORT WAVE FORCING FOR CONVECTION WILL BE BEST
ACROSS AREAS TO THE NORTH BUT IT WILL BE ADEQUATE FOR SCATTERED
SHOWERS/THUNDERSTORMS ACROSS NORTH AND CENTRAL TEXAS AS THE
SOUTHERN END OF THE TROUGH MOVES ACROSS THE REGION. WE WILL START
OUT WITH LOW CHANCE POPS THURSDAY AFTERNOON/EVENING...THEN
INCREASE POPS WEST TO EAST ON FRIDAY AS THE UPPER TROUGH NEARS.
ALTHOUGH SHEAR WILL BE LOW ON FRIDAY...CAPE WILL BE ADEQUATE FOR
SOME STRONG STORMS WITH GUSTY WINDS...AND LOCALLY HEAVY RAINFALL
DUE TO PWATS NEAR 2 INCHES. AS THE UPPER TROUGH MOVES INTO THE
MIDWEST AND EAST TEXAS OVER THE WEEKEND...WE WILL BE TRIMMING POPS
WEST TO EAST TO MATCH ITS POSITION. BY SUNDAY...POPS WILL BE
LIMITED TO 20S OVER THE FAR EASTERN COUNTIES. DRY WEATHER WILL
SETTLE IN FOR SUNDAY NIGHT THROUGH TUESDAY.
TEMPERATURES WILL BE RESPONDING TO SLIGHTLY LOWER HEIGHTS ALOFT DUE
TO THE TUTT AND THE PASSAGE OF THE UPPER TROUGH LATER IN THE
WEEK. HIGHS ON THURSDAY WILL WILL BE A DEGREE OR TWO COOLER THAN
THOSE EXPECTED TODAY...AND ABOUT 5 DEGREES COOLER ON FRIDAY DUE
TO ADDITIONAL CLOUDS AND SCATTERED CONVECTION. EXPECTING HIGHS TO
CREEP UP A FEW DEGREES ON SUNDAY WITH GENERALLY MID 90S THE FIRST
OF NEXT WEEK. LOW TEMPS WILL NOT CHANGE MUCH....BUT FRIDAYS
CONVECTION COULD RESULT IN SOME LOWER 70S OUT WEST AND ALONG THE
RED RIVER ON SATURDAY MORNING.
LOOKING AHEAD...HIGH PRESSURE ALOFT WILL BE BUILDING BACK OVER
THE REGION THE FIRST WEEK OF SEPTEMBER WITH THE WESTERLIES
REMAINING OVER THE NORTHERN PART OF THE COUNTRY. AS A
RESULT...THERE DOES NOT SEEM TO BE ANOTHER OPPORTUNITY FOR COOLER
WEATHER OR RAIN/STORMS UNTIL AFTER THE 10TH OF SEPTEMBER. 75
&&
.PRELIMINARY POINT TEMPS/POPS...
DALLAS-FT. WORTH, TX 98 77 97 78 93 / 10 10 10 20 50
WACO, TX 99 74 97 76 93 / 10 10 20 10 40
PARIS, TX 94 71 95 73 92 / 10 10 10 20 50
DENTON, TX 96 74 96 76 92 / 10 10 10 20 50
MCKINNEY, TX 96 72 96 75 92 / 10 10 10 20 50
DALLAS, TX 98 77 97 78 92 / 10 10 10 20 50
TERRELL, TX 97 75 96 75 93 / 10 10 10 20 50
CORSICANA, TX 96 76 97 75 93 / 10 10 10 10 40
TEMPLE, TX 98 73 96 75 93 / 10 10 20 20 50
MINERAL WELLS, TX 99 72 98 74 93 / 10 10 10 20 50
&&
.FWD WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
05/82
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
328 PM CDT WED AUG 27 2014
.SHORT TERM...(THIS EVENING THROUGH THURSDAY NIGHT)
ISSUED AT 328 PM CDT WED AUG 27 2014
FORECAST FOCUS IS ON PRECIPITATION TIMING AND AMOUNTS...THREAT
FOR HEAVY RAIN WITH LOCALIZED FLOODING.
AS OF MID AFTERNOON...WATER VAPOR IMAGERY OVERLAID WITH RAP 500
MB HEIGHTS SHOWED DECAYING DISTURBANCE ACROSS IOWA...WITH MAIN
CLOSED LOW ROTATING INTO NORTHWESTERN COLORADO. WEAK IMPULSES WERE
RIDING THE PERIPHERY OF THE TROUGH...AND IT IS THESE IMPULSES THAT
WILL BE THE PLAYERS FOR THE NEXT 24 TO 48 HOURS ACROSS THE UPPER
MISSISSIPPI RIVER VALLEY.
AT THE SURFACE...LINGERING SHOWERS AND THUNDERSTORMS HAVE BEEN
CONFINED TO SOUTHERN AND SOUTHWESTERN IOWA...KEEPING FRONTAL
BOUNDARY ACROSS SOUTHERN IOWA / NORTHERN MISSOURI. THE 65F
DEWPOINT LINE IS GENERALLY SOUTH OF I-80.
THE LARGEST CHANGES TO ONGOING FORECAST HAVE BEEN RELATED TO
PRECIPITATION TIMING...AS 27.12Z MODEL CYCLES TREND TOWARD A LATER
ARRIVAL OF THE GREATEST 850MB MOISTURE TRANSPORT OVERNIGHT THROUGH
THE DAY ON THURSDAY. MOST OF THE DETERMINISTIC AND HI-RES MODELS
SHOW A SHIELD OF RAIN SHOWERS WITH EMBEDDED THUNDERSTORMS REACHING
NORTHEAST IOWA / SOUTHEAST NOT UNTIL THE EARLY MORNING HOURS /4 TO
6 AM/ THEN MOVING INTO WESTERN WISCONSIN MID TO LATE MORNING.
PRECIPITATION CHANCES HAVE BEEN ADJUSTED...BUT OVERALL CONFIDENCE
REMAINS VERY HIGH SO KEPT 90 TO 100 CHANCES.
THE NOSE OF THE 850MB MOISTURE TRANSPORT LIFTS THROUGH THE AREA
DURING THE DAY...SO ANY COMPLEX OF SHOWERS/STORMS WILL LIKELY BE
PROGRESSIVE. HOWEVER...THE ATMOSPHERE WILL INCREASINGLY BECOME
MORE FAVORABLE FOR HEAVY RAINFALL RATES...AS PWATS APPROACH 2
INCHES. WARM CLOUD DEPTHS EXCEED 4 KM ACROSS MUCH OF THE AREA. THE
STORM TOP WINDS ARE PROGGED TO BE 25 TO 30 KTS...WHICH SHOULD HELP
KEEP CONVECTION PROGRESSIVE ENOUGH. THOUGH WITH BROAD WARM AIR
ADVECTION AND ISENTROPIC LIFT DURING THE DAY...HAVE KEPT HIGH
PRECIPITATION CHANCES THROUGH THE EVENING HOURS. THE GREATER FOCUS
SEEMS TO BE ON WESTERN INTO NORTH CENTRAL WISCONSIN...THOUGH MOST
AREAS WILL SEE SHOWERS/STORMS THROUGHOUT THE DAY.
.LONG TERM...(FRIDAY THROUGH WEDNESDAY)
ISSUED AT 328 PM CDT WED AUG 27 2014
THE MAIN 500MB SHORTWAVE BEGINS TO SWING THROUGH THE UPPER
MIDWEST FRIDAY EVENING INTO SATURDAY MORNING...WITH THE GREATEST
500-300MB PV ADVECTION ALIGNED FROM CENTRAL AND EASTERN IOWA INTO
SOUTHERN WISCONSIN. THE MOIST AIRMASS WILL LINGER THROUGH THIS
PERIOD AS WELL...AS THE OVERALL ENVIRONMENT SUPPORTS EFFICIENT
RAIN PRODUCES. THE SURFACE FRONT WILL LIKELY STALL FROM IOWA INTO
SOUTHERN WISCONSIN AND COULD BE THE FOCUS FOR SEVERAL EPISODES FOR
SHOWERS/STORMS. DEPENDING ON THE HEAVY RAINFALL OUTCOME IN ROUND
ONE...THIS PERIOD WILL NEED TO BE WATCHED FOR REPEATED ROUNDS.
THOUGH AT THIS POINT...IT LOOKS LIKE DIFFERENT AREAS WILL SEE THE
ROUNDS OF HEAVIER RAINFALL.
IT DOES LOOK LIKE BY SATURDAY MOST OF THE UPPER LEVEL ENERGY
MOVES EAST...AND THE PRECIPITATION CHANCES ARE CONFINED TO
SOUTHERN AND CENTRAL WISCONSIN. FOR THOSE PLANNING ACTIVITIES THIS
UPCOMING HOLIDAY WEEKEND...THE SATURDAY NIGHT TO SUNDAY MORNING
TIMEFRAME HAS THE GREATEST LIKELIHOOD TO SEE DRIER PERIODS.
SUNDAY THROUGH MONDAY WILL FEATURE AN APPROACHING UPPER LEVEL
SHORTWAVE FROM THE NORTHERN PLAINS. 27.12Z MODELS ALREADY SHOW
THIS FEATURE TO BE A BIT VIGOROUS AS IT SWINGS THROUGH. AT THE
SURFACE...THIS WILL DRIVE A COLD FRONT THROUGH THE UPPER MIDWEST.
THERE REMAINS SOME TIMING DIFFERENCES BETWEEN THE GFS/ECMWF/GEM
BUT THE TREND HAS BEEN FOR THE FRONTAL PASSAGE TO BE LATE SUNDAY
NIGHT OR EARLY MONDAY MORNING. SEVERE CHANCES LOOK LIMITED RIGHT
NOW GIVEN TIMING BUT 500 TO 1000 MUCAPE TRANSLATES AHEAD OF THE
FRONT WITH MARGINAL 0-6KM SHEAR VALUES /20 KTS/. SOMETHING TO KEEP
AN EYE WITH THE HOLIDAY WEEKEND...ESPECIALLY IF THE TIMING BECOMES
MORE FAVORABLE DURING PEAK HEATING.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z THURSDAY AFTERNOON)
ISSUED AT 1230 PM CDT WED AUG 27 2014
GOOD VFR CONDITION EXPECT THRU THIS AFTERNOON/EVENING AS COOLER/DRIER
HIGH PRESSURE HOLDS OVER THE AREA. INCREASING MOISTURE/LIFT SPREAD
NORTHEAST TOWARD THE AREA AFTER MIDNIGHT...REACHING THE KRST AREA
TOWARD MORNING AND THE KLSE AREA AROUND MID MORNING THU. INSTABILITY
IS INITIALLY LIMITED...WITH MAINLY -SHRA EXPECTED WHEN THE PRECIP
SPREADS INTO THE AREA. WITH THE DRIER HIGH PRESSURE TO OVERCOME...
CIGS/VSBYS WILL BE VFR/MVFR AS THE PRECIP FIRST ARRIVES. WITH
INCREASING LIFT/INSTABILITY THRU THU MORNING...TSRA EXPECTED TO
BECOME EMBEDDED IN THE BROADER SHRA/RAIN AREA. INCLUDED TEMPO TSRA
AT KRST AFTER 13Z AND KLSE AFTER 16Z...HOWEVER TSRA THU MORNING MAY
BE MORE OCCASIONAL RUMBLES OF THUNDER VS. MORE TYPICAL JULY/AUG
CONVECTION. WITH CONTINUED RAIN THU MORNING AND SATURATION OF THE
LOWER LEVELS...CIGS/VSBYS AT KRST TO LOWER INTO MVFR/IFR AFTER
15Z...WITH THESE LOWER CIGS/VSBYS LOOKING TO REACH KLSE NEAR/AFTER
18Z. MVFR/IFR CIGS/VSBYS IN SHRA/TSRA THEN LOOK TO PERSIST THU
AFTERNOON/NIGHT.
&&
.HYDROLOGY...THURSDAY THROUGH FRIDAY NIGHT
ISSUED AT 328 PM CDT WED AUG 27 2014
VERY FAVORABLE SETUP FOR EFFICIENT...HEAVY RAIN PRODUCERS OVER
THE NEXT FEW DAYS. WARM CLOUD DEPTHS CONTINUE TO HOVER NEAR 4000 M
/IF NOT HIGHER/ WHILE PWATS PEAK AROUND 2 INCHES THURSDAY-
THURSDAY NIGHT. HEAVIER RAIN SIGNALS ARE PROGRESSIVE...THROUGH
NORTHERN IOWA INTO SOUTHEAST MINNESOTA AND THEN NORTH CENTRAL
WISCONSIN. FOR ROUND TWO...THE HIGHER THREAT LOOKS TO BE ACROSS
EASTERN IOWA INTO SOUTHERN WISCONSIN.
RUN TOTAL QPF FROM THE EC/GFS/GEM THROUGH SATURDAY RANGE FROM 2
TO 4 INCHES. LOCALLY HIGHER AMOUNTS ARE LIKELY. AT THIS
MOMENT...THINK THERE COULD BE QUICK RISES ON SOME RIVERS...BUT
SHOULD STAY WITHIN BANK. AS ALONG AS STORMS MOVE...AND AREAS DON/T
GET REPEATED HITS...THE FLASH FLOOD THREAT IS REDUCED. ALL
SAID...WITH THE HIGH LIKELIHOOD OF HEAVY RAIN...AND THE POTENTIAL
FOR SIGNIFICANT AMOUNTS...WILL MAINTAIN HYDROLOGIC OUTLOOK TO
HIGHLIGHT THE THREATS. A FLASH FLOOD WATCH MAY BE NECESSARY IF
SIGNALS ARE FOR THE ROUNDS OF HEAVY RAINFALL LOOK TO REPEAT OVER
THE SAME AREA.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...ZT
LONG TERM....ZT
AVIATION.....RRS
HYDROLOGY....ZT/RIECK
AREA FORECAST DISCUSSION
NWS CHEYENNE WY
1137 AM MDT WED AUG 27 2014
.SHORT TERM...(TODAY THROUGH FRIDAY)
ISSUED AT 355 AM MDT WED AUG 27 2014
CLOSED UPPER LOW WAS ENTERING UT FROM NV PER WATER VAPOR IMAGERY.
SOUTHERLY FLOW ALOFT DRAWING MOISTURE FROM HURRICANE MARIE WEST OF
BAJA CA INTO THE CENTRAL AND SOUTHERN ROCKY MOUNTAIN REGION.
SHORTWAVE LIFTING NORTHWARD ACROSS NORTHWEST CO PRODUCING SCATTERED
SHOWERS AND ISOLATED TSTORMS. OTHER CONVECTION WAS DEVELOPING NORTH
OF A STALLED SURFACE FRONT FROM NORTHEAST CO INTO CENTRAL NE. SKIES
WERE PARTLY TO MOSTLY CLOUDY WITH SOME STRATUS FORMING OVER EAST
CENTRAL WY. WINDS WERE LIGHT AND VARIABLE.
THE 00Z SHORT RANGE MODEL GUIDANCE IS IN GOOD AGREEMENT PROGGING THE
UPPER LOW PRESSURE CENTER EVOLVING INTO A OPEN WAVE AS IT PROGRESSES
SLOWLY EAST INTO WESTERN CO THIS AFTERNOON. THE MAJORITY OF THE
MODELS INCLUDING THE ESRL HRRR DEVELOP AN WEST-EAST BAND OF SHOWERS
AND EMBEDDED TSTORMS ALONG THE I-80 CORRIDOR AFTER 12Z AS THE
SHORTWAVE LIFTS NORTH INTO SOUTHERN WY. ADDITIONAL SHOWERS AND
SCATTERED TSTORMS DEVELOP THIS AFTERNOON WITH UPSLOPE SOUTHEASTERLY
FLOW. LOW/MID LEVEL INSTABILITY AND 0-6KM SHEAR PROFILES ARE NOT
CONDUCIVE FOR SEVERE TSTORM DEVELOPMENT...HOWEVER PRECIP WATER
VALUES EXCEED AN INCH MORE INDICATIVE OF LOCALLY HEAVY RAINFALL.
STORM MOTION WILL BE TO THE NORTH AND NORTHEAST AROUND 25 KT WHICH
SHOULD MITIGATE THE FLOOD THREAT. FOLLOWED THE HPC QPF WHICH PROGS
0.5-1.0 INCH RAINFALL OVER THE CWA. IT WILL BE 5-10 DEGREES COOLER
TODAY COMPARED TO YESTERDAY WITH 700MB TEMPERATURES AROUND 7C.
SHOWER COVERAGE WILL DECREASE FROM NUMEROUS THIS EVENING TO LOW END
SCATTERED LATER TONIGHT.
THURSDAY WILL TREND DRIER AS THE UPPER TROUGH AND BETTER MOISTURE
SHIFT SOUTH AND EAST OF THE CWA. STILL CANNOT RULE OUT ISOLATED TO
SCATTERED CONVECTION ALONG AND SOUTH OF I-80 THOUGH. QPF WILL BE
LIGHTER...GENERALLY LESS THAN A QUARTER INCH. HIGH TEMPERATURES WILL
BE 3-5 DEGREES WARMER...ESPECIALLY EAST CENTRAL WY AND NORTHERN NE
PANHANDLE WITH GREATER INSOLATION.
TRANSITORY SHORTWAVE RIDGE THURSDAY NIGHT SHIFTS EAST FRIDAY AS A
SHORTWAVE TROUGH MOVES EAST ACROSS MT AND NORTHERN WY. THIS SYSTEM
WILL NOT HAVE MUCH AVAILABLE MOISTURE TO WORK WITH...BUT DYNAMICS
ENOUGH TO OVERCOME AND PRODUCE ISOLATED AFTERNOON CONVECTION ALONG
AND NORTH OF A LINE FROM DOUGLAS TO CHADRON...AS WELL AS OVER THE
MOUNTAINS. 700MB TEMPERATURES RISE TO AROUND 10C FRIDAY AFTERNOON
WITH READINGS IN THE 80S EAST OF THE LARAMIE RANGE.
.LONG TERM...(FRIDAY NIGHT THROUGH TUESDAY)
ISSUED AT 330 AM MDT WED AUG 27 2014
MILD AND MAINLY DRY WEATHER FRI NIGHT INTO SATURDAY AS A MINOR UPPER
RIDGE MOVES EAST ACROSS THE AREA. A QUICK-MOVING SHORTWAVE SHOULD
PASS MAINLY NORTH OF THE CWA LATE SAT BUT COULD BRING A FEW SHOWERS
TO MAINLY NORTHERN PARTS OF THE CWA THEN. MORE SIGNIFICANT UPPER TROF
WILL MOVE ACROSS SUNDAY BRINGING MORE WIDESPREAD SHOWERS AND A FEW
TSTMS. ECMWF MORE BULLISH WITH THIS SYSTEM WITH THE GFS CONSIDERABLY
WEAKER. MILD AND MAINLY DRY WEATHER RETURNS FOR MONDAY AND TUESDAY
AS THE CWA RESIDES ON THE SOUTHERN SIDE OF BROAD UPPER CYCLONIC FLOW
THAT WILL PROGRESS ACROSS THE NORTHERN PART OF THE COUNTRY.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z THURSDAY MORNING)
ISSUED AT 1130 AM MDT WED AUG 27 2014
SCATTERED TO NUMEROUS SHOWERS AND STORMS CAN BE EXPECTED ACROSS
SOUTHEAST WY AND THE WESTERN NE PANHANDLE TODAY. MOST TERMINALS
WILL SEE LOWER CIGS BETWEEN 5K AND 8K FEET AGL THROUGH THE TAF
PERIOD...WITH OCCASIONAL MVFR CONDITIONS WITH BKN-TO-OVC SKIES
AROUND 2K FEET. LOWEST CIGS/VSBYS WILL OCCUR BENEATH SHOWERS AND
STORMS. A FEW STRONGER STORMS ARE POSSIBLE THIS AFTN FOR THE NE
PANHANDLE SITES...WITH TORRENTIAL DOWNPOURS AND STRONG/VARIABLE
WINDS POSSIBLE ALONG WITH SMALL HAIL. SHOWER ACTIVITY IS LIKELY
TO PERSIST ACROSS MUCH OF THE REGION OVERNIGHT. WE CANNOT RULE
OUT MVFR CIGS LATE TONIGHT OR EARLY THU...ESPECIALLY IN AREAS
WHICH RECIEVE HEAVIER RAINFALL THIS AFTN.
&&
.FIRE WEATHER...
ISSUED AT 252 AM MDT WED AUG 27 2014
A LOW PRESSURE SYSTEM OVER UTAH EARLY THIS MORNING WILL SLOWLY TRACK
EAST THROUGH COLORADO DURING THE NEXT 24 HOURS...AND INTO THE CENTRAL
PLAINS BY FRIDAY. NUMEROUS SHOWERS AND SCATTERED THUNDERSTORMS WILL
PRODUCE WETTING RAINFALL TODAY AND TONIGHT. DRIER AND WARMER WEATHER
WILL RETURN THURSDAY AND CONTINUE THROUGH SATURDAY...ALONG WITH GUSTY
WEST TO SOUTHWEST WINDS. THERE WILL BE A SLIGHT CHANCE OF SHOWERS
AND THUNDERSTORMS SUNDAY AND LABOR DAY WITH THE PASSAGE OF A UPPER
LEVEL TROUGH AND PACIFIC COLD FRONT.
&&
.CYS WATCHES/WARNINGS/ADVISORIES...
WY...NONE.
NE...NONE.
&&
$$
SHORT TERM...JAMSKI
LONG TERM...RE
AVIATION...HAMMER
FIRE WEATHER...JAMSKI