Forecast Discussions mentioning any of
"HRRR" "RAP" "RR" "RUC13" "RUC" received at GSD on 08/26/14
SOUTHWEST CALIFORNIA AREA FORECAST DISCUSSION
NWS LOS ANGELES/OXNARD CA
906 PM PDT MON AUG 25 2014
.SYNOPSIS...
SLIGHTLY BELOW NORMAL DAYTIME HIGHS ARE EXPECTED AGAIN ON TUESDAY
WITH A TROUGH OF LOW PRESSURE OVERHEAD. A SIGNIFICANT WARM UP IS
EXPECTED FOR THE SECOND HALF OF THE WEEK AS A RIDGE OF HIGH
PRESSURE DEVELOPS. THE HIGH PRESSURE WILL ALSO RESULT IN A
SHRINKING OF THE MARINE LAYER AND LESS NIGHT THROUGH MORNING LOW
CLOUD COVERAGE. A COOLING TREND IS THEN LIKELY INTO EARLY NEXT
WEEK.
&&
.UPDATE...
ONSHORE FLOW IS WEAKENING THIS EVENING EVEN AS TROUGH APPROACHES
THE AREA. WATER VAPOR IMAGERY INDICATES A TROUGH OF LOW PRESSURE
CONTINUING TO DIG INTO THE GREAT BASIN THIS EVENING. A DECENT
CLOUD SHIELD CAN BE SEEN OVER THE SAN JOAQUIN VALLEY ASSOCIATED
WITH THE TROUGH. HOWEVER...THE TROUGH IS DOING BATTLE WITH A
STRONG RIDGE OF HIGH PRESSURE OVER THE BIG BEND OF TEXAS. MODEL
SOLUTIONS ALL SUGGEST THE HIGH PRESSURE SYSTEM WINNING OUT. WITH
WEAKENING ONSHORE FLOW...THE MARINE LAYER DEPTH CONTINUES TO THIN
WITH THE LATEST AMDAR SOUNDINGS FROM KLAX INDICATING A DEPTH
AROUND 1100 FEET THIS EVENING. WITH LESS ONSHORE FLOW AND A
THINNER MARINE LAYER...A SLIGHT WARM UP SHOULD OCCUR ON TUESDAY.
THE CURRENT PACKAGE ADDRESS THE WARMING FOR TUESDAY REASONABLY.
AS THE TROUGH BRUSHES THE AREA...SOME MIDDLE AND HIGH LEVEL CLOUDS
WILL LIKELY RESULT. 13-KM RAP MODEL SOLUTIONS SUGGEST A NARROW
WINDOW FOR CONVECTIVE STORMS ON TUESDAY OVER THE EASTERN SAN
GABRIEL RANGE...BUT ALL OTHER MODEL SOLUTIONS KEEP THE CONVECTIVE
POTENTIAL TO THE EAST OF THE AREA. SOME CLOUDS HAVE BEEN ADDED FOR
THE SAN GABRIEL RANGE. WITH CONFIDENCE LOW IN THE MODEL SOLUTIONS
AT THIS TIME...NO MENTION OF CONVECTIVE SHOWERS WAS ADDED FOR THE
EASTERN SAN GABRIEL RANGE FOR TUESDAY.
&&
.PREV DISCUSSION...
SHORT TERM...ONSHORE PRESSURE WEAKEN FURTHER INTO WEDNESDAY...AND
HOLD COURSE ON THURSDAY. AS A RESULT...WE SHOULD SEE A MORE
NOTICEABLE WARMUP ON WEDNESDAY AND THURSDAY AS THE RIDGE PEAKS.
BY WEDNESDAY AND THURSDAY...THE INVERSION WILL STRENGTHEN WHICH
SHOULD KEEP CLOUDS OUT OF THE VALLEYS AND MAY EVEN KEEP CLOUDS OFF
SOME OF THE COASTS. CURRENT COASTAL TEMPERATURE FORECASTS ARE
CONSERVATIVE FACTORING IN THE MARINE LAYER UNCERTAINTY...AND
TEMPERATURES MAY END UP A FEW DEGREES HIGHER IF STRATUS INDEED
STAYS AWAY. DENSE FOG MAY BE A CONCERN AS WELL.
THE OTHER WRINKLE IS INCREASING NORTHWEST FLOW THURSDAY AND THURSDAY
NIGHT. AT THIS POINT EXPECTING A NEAR ADVISORY SUNDOWNER OVER SBA
COUNTY. THIS SHOULD KEEP CLOUDS OUT OF SRN SBA AND VENTURA
COUNTY...AND REALLY HEAT UP THE SOUTH COAST...MAYBE EVEN APPROACHING
HIGH TEMPERATURE RECORDS. IF A COASTAL EDDY ENDS UP FORMING FROM
THIS...LA COUNTY COULD SEE SOME COOLING STRATUS FORM.
FOR UP COMING SURF EVENT...SEE BEACHES SECTION BELOW.
LONG TERM...NOT A WHOLE LOT OF CHANGE FROM THURSDAY INTO FRIDAY.
CONTINUED WARM AND ABOVE NORMAL TEMPERATURES WITH A SHALLOW MARINE
LAYER AND LIMITED STRATUS...AS THE RIDGE ALOFT REMAINS OVER
SOUTHERN CALIFORNIA. A SLIGHTLY STRONGER SUNDOWNER IS EXPECTED ON
FRIDAY AND SHOULD APPROACH WIND ADVISORY STRENGTH.
EXTENDED MODELS ARE SHOWING A BROAD TROUGH FORMING OVER THE
NORTHWEST STATES...WHICH WOULD PUSH THE RIDGE TOWARD THE SOUTHEAST.
MODERATELY CONFIDENT OF A COOLING TREND WITH INCREASING ONSHORE FLOW
EARLY NEXT WEEK...BUT THERE IS SOME DISCREPANCIES AS TO HOW MUCH THE
RIDGE MOVES AWAY AND THEREFORE HOW STRONG THAT TREND ENDS UP BEING.
CURRENT FORECAST IS WEIGHTED TOWARD THE BETTER PERFORMING AND COOLER
GFS SOLUTION...BUT DID TEMPER THE COOLING SOME FROM THE PREVIOUS
FORECASTS.
&&
.AVIATION...25/2358Z.
IFR TO MVFR CONDITIONS WILL LIKELY SPREAD INTO COASTAL TERMINALS
BETWEEN 05Z AND 13Z...WITH A CHANCE OF LIFR CONDITIONS AT TERMINALS
NORTH OF POINT CONCEPTION BETWEEN 10Z AND 14Z. VFR CONDITIONS SHOULD
REDEVELOP BETWEEN 16Z AND 17Z.
KLAX...THERE IS A 60 PERCENT CHANCE OF MVFR CONDITIONS BETWEEN 08Z
AND 17Z. VFR CONDITIONS SHOULD REDEVELOP BETWEEN 16Z AND 17Z.
KBUR...VFR CONDITIONS ARE EXPECTED THROUGHOUT THE PERIOD. THERE IS A
20 PERCENT CHANCE OF IFR TO MVFR CONDITIONS BETWEEN 10Z AND 16Z.
&&
.MARINE...25/900 PM.
SMALL CRAFT ADVISORY CONDITIONS FOR HAZARDOUS SEAS MAY DEVELOP
TUESDAY NIGHT SOUTH OF POINT CONCEPTION AND PERSIST THROUGH
WEDNESDAY AS SWELLS FROM HURRICANE MARIE MOVE ACROSS THE AREA.
ALSO...SMALL CRAFT CONDITIONS FOR WINDS ARE POSSIBLE EACH AFTERNOON
THURSDAY THROUGH SATURDAY IN THE VICINITY OF POINT CONCEPTION AND
THE NORTHERN CHANNEL ISLANDS WITH GUST TO 30 KNOTS.
&&
.BEACHES...25/900 PM.
HIGH SURF ADVISORY FOR EXPOSED SOUTH FACING SHORES SOUTH OF POINT
CONCEPTION REMAINS IN EFFECT FROM TUESDAY THROUGH FRIDAY
CONTINUES. HURRICANE MARIE SWELL`S WILL IMPACT THE EXPOSED SOUTH
FACING SHORES NORTH OF POINT CONCEPTION AS WELL AND A HIGH RIP
CURRENT RISK IS EXPECTED. THE CONFIDENCE IS RELATIVELY HIGH AS
MARIE WILL REMAIN A HURRICANE THROUGH TUESDAY EVENING. MARIE IS
EXPECTED TO REMAIN A MAJOR HURRICANE WHILE THE FETCH SHIFTS TO
160-190 DEGREES THROUGH EARLY TUESDAY. AN EXTRATROPICAL STORM IN
THE SOUTHERN HEMISPHERE IS EXPECTED TO STRENGTHEN WITH STORM FORCE
WINDS WITHIN 190-210 DEGREES RELATIVE SOUTHERN CALIFORNIA THIS
WEDNESDAY. THE SWELLS GENERATED ARE EXPECTED TO ARRIVE NEXT WEEK
THURSDAY INTO FRIDAY. PLEASE SEE THE LATEST LAXCFWLOX FOR CURRENT
EVENT DETAILS.
&&
.LOX WATCHES/WARNINGS/ADVISORIES...
HIGH SURF ADVISORY (SEE LAXCFWLOX).
BEACH HAZARDS STATEMENT (SEE LAXCFWLOX).
HIGH RIP CURRENT RISK (SEE LAXSRFLOX).
&&
$$
PUBLIC...HALL/KITTELL
AVIATION...HALL
MARINE/BEACHES...HALL
SYNOPSIS...SUKUP
WWW.WEATHER.GOV/LOSANGELES
AREA FORECAST DISCUSSION
NWS PUEBLO CO
754 PM MDT MON AUG 25 2014
.UPDATE...
ISSUED AT 753 PM MDT MON AUG 25 2014
UPDATED TO CLEAR PUEBLO CTY FROM THE WATCH...AND ADJUST POPS PER
RADAR AND MODEL TRENDS. ROSE
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 MIAMI FL
1003 PM EDT MON AUG 25 2014
.UPDATE...
JUST A QUICK UPDATE TO RELATE THAT THE HIGH RISK OF RIP CURRENTS
WAS EXTENDED TO INCLUDE ALL THE ATLANTIC COAST BEACHES THROUGH TUESDAY
AFTERNOON.
60
&&
.PREV DISCUSSION... /ISSUED 845 PM EDT MON AUG 25 2014/
UPDATE...
IN CONTRAST TO LAST NIGHT, A MUCH DRIER AIRMASS WILL BE ARRIVING
FROM THE NORTHEAST INTO TUESDAY AS PWATS ARE AS LOW AS 1.5" JUST
OFF THE EAST COAST OF FLORIDA. THIS AIRMASS IS A PRODUCT OF NOT
ONLY BROAD SURFACE HIGH PRESSURE AND SUBSIDENCE MOVING TO THE
EAST COAST, BUT ALSO SUBSIDENCE WELL REMOVED FROM CRISTOBAL. DEEP
NORTHEASTERLY FLOW WILL DELIVER THE RELATIVELY DRIER AIRMASS TO
SOUTH FLORIDA, FIRST ACROSS PALM BEACH COUNTY INTO TOMORROW
MORNING. HOWEVER, DEEP MOISTURE REMAINS THROUGH THE GULF WATERS
WHERE THUNDERSTORMS ARE STILL POSSIBLE THROUGH TONIGHT. SHOWERS
WILL REMAIN ACROSS THE ATLANTIC WATERS, WITH SOME SURVIVING TO THE
COASTLINE OVER THE NEXT FEW HOURS.
MARINE...
NORTHEASTERLY WINDS NEAR 20 KTS AND SEAS 7 FEET AND ABOVE OVER THE
GULF STREAM NECESSITATED A SMALL CRAFT ADVISORY FOR ALL OF THE
ATLANTIC WATERS. HOWEVER THE SMALL CRAFT ADVISORY IS ONLY FOR
WAVES OFF OF BROWARD/DADE COUNTIES. A HIGH RIP CURRENT RISK IS ALONG
COASTAL PALM BEACH. THE PRESSURE GRADIENT BETWEEN HIGH PRESSURE
NEAR THE EAST COAST OF THE CONTINENTIAL UNITED STATES AND
CRISTOBAL IS THE CAUSE. WINDS WILL ALSO BE 20 KTS OR MORE THROUGH
OUR OFFSHORE GULF WATERS TONIGHT, IN ADDITION TO LAKE OKEECHOBEE.
ALL OF THESE ADVISORIES COULD VERY WELL BE EXTENDED IN DURATION
PAST TOMORROW MORNING IF WINDS/WAVES DO NOT SUBSIDE. WINDS WILL
GENERALLY BE FROM THE SOUTH AND LIGHTER BY LATE WEEK AND THE
WEEKEND.
PREV DISCUSSION... /ISSUED 808 PM EDT MON AUG 25 2014/
AVIATION...
EASTERLY WINDS CONTINUE TO INCREASE ACR0SS THE REGION. THE
ATLANTIC COAST TERMINALS COULD EXPERIENCE WINDS AROUND 15 KNOTS
AT TIMES WITH PASSING SHOWERS LIKELY THROUGH AT LEAST 03Z. WITH
ANY PASSING SHOWERS GUSTS TO NEAR 30 KNOTS ARE POSSIBLE AND VERY
BRIEF PERIODS OF NEAR IFR CONDITIONS MAY BE POSSIBLE. AN
OCCASIONAL LIGHTNING STRIKE WILL ALSO BE POSSIBLE WITH PASSING
SHOWERS. BY MID TUESDAY MORNING MAINLY EASTERLY WINDS NEAR THE 15
KNOT RANGE ARE FORECAST WITH A DRYING TREND EXPECTED AFTER 06Z
TONIGHT.
60
PREV DISCUSSION... /ISSUED 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 / 40 20 20 30
FORT LAUDERDALE 81 91 80 91 / 30 20 20 30
MIAMI 80 91 79 91 / 30 20 20 40
NAPLES 78 92 77 91 / 40 20 10 40
&&
.MFL WATCHES/WARNINGS/ADVISORIES...
FL...HIGH RIP CURRENT RISK THROUGH TUESDAY AFTERNOON FOR FLZ168-172-
173.
AM...SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS UNTIL 8 AM EDT TUESDAY
FOR AMZ651-671.
SMALL CRAFT ADVISORY UNTIL 8 AM EDT TUESDAY FOR AMZ650-670.
SMALL CRAFT ADVISORY FOR WINDS UNTIL 8 AM EDT TUESDAY FOR AMZ610.
GM...SMALL CRAFT ADVISORY FOR WINDS UNTIL 8 AM EDT TUESDAY FOR GMZ676.
&&
$$
SHORT TERM...60/BD
LONG TERM....21/KM
AREA FORECAST DISCUSSION
NWS MIAMI FL
845 PM EDT MON AUG 25 2014
.UPDATE...
IN CONTRAST TO LAST NIGHT, A MUCH DRIER AIRMASS WILL BE ARRIVING
FROM THE NORTHEAST INTO TUESDAY AS PWATS ARE AS LOW AS 1.5" JUST
OFF THE EAST COAST OF FLORIDA. THIS AIRMASS IS A PRODUCT OF NOT
ONLY BROAD SURFACE HIGH PRESSURE AND SUBSIDENCE MOVING TO THE
EAST COAST, BUT ALSO SUBSIDENCE WELL REMOVED FROM CRISTOBAL. DEEP
NORTHEASTERLY FLOW WILL DELIVER THE RELATIVELY DRIER AIRMASS TO
SOUTH FLORIDA, FIRST ACROSS PALM BEACH COUNTY INTO TOMORROW
MORNING. HOWEVER, DEEP MOISTURE REMAINS THROUGH THE GULF WATERS
WHERE THUNDERSTORMS ARE STILL POSSIBLE THROUGH TONIGHT. SHOWERS
WILL REMAIN ACROSS THE ATLANTIC WATERS, WITH SOME SURVIVING TO THE
COASTLINE OVER THE NEXT FEW HOURS.
&&
.MARINE...
NORTHEASTERLY WINDS NEAR 20 KTS AND SEAS 7 FEET AND ABOVE OVER THE
GULF STREAM NECESSITATED A SMALL CRAFT ADVISORY FOR ALL OF THE
ATLANTIC WATERS. HOWEVER THE SMALL CRAFT ADVISORY IS ONLY FOR
WAVES OFF OF BROWARD/DADE COUNTIES. A HIGH RIP CURRENT RISK IS ALONG
COASTAL PALM BEACH. THE PRESSURE GRADIENT BETWEEN HIGH PRESSURE
NEAR THE EAST COAST OF THE CONTINENTIAL UNITED STATES AND
CRISTOBAL IS THE CAUSE. WINDS WILL ALSO BE 20 KTS OR MORE THROUGH
OUR OFFSHORE GULF WATERS TONIGHT, IN ADDITION TO LAKE OKEECHOBEE.
ALL OF THESE ADVISORIES COULD VERY WELL BE EXTENDED IN DURATION
PAST TOMORROW MORNING IF WINDS/WAVES DO NOT SUBSIDE. WINDS WILL
GENERALLY BE FROM THE SOUTH AND LIGHTER BY LATE WEEK AND THE
WEEKEND.
&&
.PREV DISCUSSION... /ISSUED 808 PM EDT MON AUG 25 2014/
AVIATION...
EASTERLY WINDS CONTINUE TO INCREASE ACR0SS THE REGION. THE
ATLANTIC COAST TERMINALS COULD EXPERIENCE WINDS AROUND 15 KNOTS
AT TIMES WITH PASSING SHOWERS LIKELY THROUGH AT LEAST 03Z. WITH
ANY PASSING SHOWERS GUSTS TO NEAR 30 KNOTS ARE POSSIBLE AND VERY
BRIEF PERIODS OF NEAR IFR CONDITIONS MAY BE POSSIBLE. AN
OCCASIONAL LIGHTNING STRIKE WILL ALSO BE POSSIBLE WITH PASSING
SHOWERS. BY MID TUESDAY MORNING MAINLY EASTERLY WINDS NEAR THE 15
KNOT RANGE ARE FORECAST WITH A DRYING TREND EXPECTED AFTER 06Z
TONIGHT.
60
PREV DISCUSSION... /ISSUED 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 / 40 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 / 40 20 10 40
&&
.MFL WATCHES/WARNINGS/ADVISORIES...
FL...HIGH RIP CURRENT RISK THROUGH TUESDAY AFTERNOON FOR FLZ168.
AM...SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS UNTIL 8 AM EDT TUESDAY
FOR AMZ651-671.
SMALL CRAFT ADVISORY UNTIL 8 AM EDT TUESDAY FOR AMZ650-670.
SMALL CRAFT ADVISORY FOR WINDS UNTIL 8 AM EDT TUESDAY FOR AMZ610.
GM...SMALL CRAFT ADVISORY FOR WINDS UNTIL 8 AM EDT TUESDAY FOR GMZ676.
&&
$$
SHORT TERM...21/KM
LONG TERM....30/KOB
AREA FORECAST DISCUSSION
NWS MIAMI FL
808 PM EDT MON AUG 25 2014
.AVIATION...
EASTERLY WINDS CONTINUE TO INCREASE ACR0SS THE REGION. THE
ATLANTIC COAST TERMINALS COULD EXPERIENCE WINDS AROUND 15 KNOTS
AT TIMES WITH PASSING SHOWERS LIKELY THROUGH AT LEAST 03Z. WITH
ANY PASSING SHOWERS GUSTS TO NEAR 30 KNOTS ARE POSSIBLE AND VERY
BRIEF PERIODS OF NEAR IFR CONDITIONS MAY BE POSSIBLE. AN
OCCASIONAL LIGHT STRIKE WILL ALSO BE POSSIBLE WITH PASSING
SHOWERS. BY MID TUESDAY MORNING MAINLY EASTERLY WINDS NEAR THE 15
KNOT RANGE ARE FORECAST WITH A DRYING TREND EXPECTED AFTER 06Z
TONIGHT.
60
&&
.PREV DISCUSSION... /ISSUED 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 / 40 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 / 40 20 10 40
&&
.MFL WATCHES/WARNINGS/ADVISORIES...
FL...HIGH RIP CURRENT RISK THROUGH TUESDAY AFTERNOON FOR FLZ168.
AM...SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS UNTIL 8 AM EDT TUESDAY
FOR AMZ651-671.
SMALL CRAFT ADVISORY UNTIL 8 AM EDT TUESDAY FOR AMZ650-670.
SMALL CRAFT ADVISORY FOR WINDS UNTIL 8 AM EDT TUESDAY FOR AMZ610.
GM...SMALL CRAFT ADVISORY FOR WINDS UNTIL 8 AM EDT TUESDAY FOR GMZ676.
&&
$$
SHORT TERM...60/BD
LONG TERM....21/KM
AVIATION...60/BD
AREA FORECAST DISCUSSION...UPDATED
NWS MIAMI FL
132 PM EDT SUN AUG 24 2014
.AVIATION...
THE NORTH TO NORTHEAST WIND FLOW WILL CONTINUE OVER THE EAST COAST
TAF SITES THROUGH REST OF THE AFTERNOON HOURS BEFORE GOING LIGHT
AND VARIABLE TONIGHT. KAPF WINDS WILL REMAIN IN A WESTERLY
DIRECTION AT 5 TO 10 KNOTS BEFORE GOING LIGHT AND VARIABLE FOR
TONIGHT.
THE WEATHER WILL ALSO REMAIN DRY OVER MOST OF SOUTH FLORIDA ALONG
WITH VFR CONDITIONS IN THE CEILING AND VIS THROUGH TONIGHT. THE
ONLY EXCEPTION TO THIS IS THERE COULD BE A SHOWER OR TWO LATE THIS
AFTERNOON OVER KAPF TAF SITE. SO WILL KEEP VCSH IN UNTIL EARLY
THIS EVENING BEFORE GOING DRY FOR TONIGHT.
&&
.AVIATION...54/BNB
.PREV DISCUSSION... /ISSUED 1050 AM EDT SUN AUG 24 2014/
UPDATE...THE PWAT ON THE MIAMI SOUNDING THIS MORNING WAS
LOWER...1.54 INCHES WITH DRY AIR EVEN IN THE LOWER LEVELS. THIS
WILL LEAD TO LESS CONVECTION THAN TYPICAL. HRRR DELAYS DEVELOPMENT
AND HAS ALL CONVECTION WESTERN INTERIOR-GULF COAST AND NOT UNTIL
AFTER 3 PM AND CONTINUING WELL INTO THE EVENING. GIVEN THE DRIER
AIR, DELAYED DEVELOPMENT LOOKS REASONABLE AND THE WIND PATTERN
DOES SUGGEST A GULF COAST FOCUS...AND ALIGNED POPS AS SUCH WHICH
WAS GENERALLY IN LINE WITH THE INHERITED FORECAST BUT WITH SUBTLE
CHANGES.
TROPICAL STORM CRISTOBAL NEAR THE SE BAHAMAS IS FORECAST TO MOVE
NORTH NORTHWEST THRU WED, THEN TURN NORTHEAST. MODELS HAVE
SOLIDIFIED ON A TRACK EAST OF FLORIDA, SO ASIDE FROM AN INCREASING
RISK OF RIP CURRENTS ALONG THE ATLANTIC BEACHES AND INCREASING
SEAS OVER THE ATLANTIC, NO OTHER IMPACTS ARE EXPECTED BUT WE OF
COURSE WILL CONTINUE TO MONITOR ITS PROGRESS. /GREGORIA
&&
PREV DISCUSSION... /ISSUED 721 AM EDT SUN AUG 24 2014/
AVIATION...
DRIER WEATHER WILL PREVAIL OVER SOUTH FLORIDA TODAY WITH NORTHEAST
WIND FLOW MOST OF THE TAF SITES. THE ONLY EXCEPTION TO THIS IS FOR
KAPF TAF SITE WHERE THE WIND FLOW WILL BECOME WESTERLY AFTER
17Z DUE TO THE WEST COAST SEA BREEZE PUSHING INLAND. SO WILL KEEP
THE WEATHER DRY AT ALL OF THE EAST COAST TAF SITES TODAY AND ONLY
VCSH AT KAPF TAF SITE AFTER 17Z. THE CEILING AND VIS WILL ALSO
REMAIN IN VFR CONDITIONS TODAY.
&&
AVIATION...54/BNB
PREV DISCUSSION... /ISSUED 246 AM EDT SUN AUG 24 2014/
SHORT TERM (TODAY-TUESDAY)...
A LARGE MID LEVEL RIDGE CURRENTLY CENTERED OVER ARKANSAS WILL SLOWLY
SHIFT TO THE NORTHEAST THROUGH TUESDAY AS A STRONG TROUGH MOVES INTO
THE ATLANTIC OFF THE NEW ENGLAND COAST. THIS WILL MAINTAIN A
NORTHEAST STEERING FLOW ACROSS SOUTH FLORIDA BUT WITH PWAT
CONTINUING TO RUN BELOW THE LATE AUGUST AVERAGE SO ONLY SCATTERED
STORMS CAN BE EXPECTED OVER THE INTERIOR AND SOUTHWEST COAST.
TROPICAL DEPRESSION FOUR IS NOW OVER THE SOUTHEAST BAHAMAS AND THE
LATEST MODEL CONSENSUS IS TO KEEP THE SYSTEM WELL TO THE EAST OF THE
FLORIDA PENINSULA. THE LATEST GFS 00Z RUN ALSO IS MORE IN LINE WITH
THE ECMWF WHICH HAS CONSISTENTLY STEERED TD FOUR THROUGH OR JUST
EAST OF THE BAHAMA ISLAND CHAIN AND THEN NORTH INTO THE OPEN
ATLANTIC. SO DEPENDING ON WHAT STRENGTH THE DISTURBANCE EVENTUALLY
DEVELOPS, THE ONLY IMPACT WILL BE TO CREATE BUILDING SEAS OFF THE
PALM BEACH COAST AS NORTHEAST SWELLS BEGIN TO AFFECT THE COASTAL
WATERS. THE ONLY FLY IN THE OINTMENT WILL BE ON TUESDAY AS THE
TROUGH MOVES OUT OF THE PICTURE AS IT LIFTS TO THE NORTHEAST. THIS
WILL ALLOW THE STEERING FLOW EAST OF THE PENINSULA TO BECOME VERY
WEAK AND THE TROPICAL SYSTEM MAY DRIFT A LITTLE TO THE WEST. SO
RESIDENTS OF SOUTH FLORIDA SHOULD CONTINUE TO MONITOR THE LATEST
FORECASTS FROM NHC.
LONG TERM (WEDNESDAY-SATURDAY)...
THE GFS AND ECMWF ARE IN FAIR AGREEMENT IN THE EXTENDED PERIOD WITH
A SOUTHWEST TO WEST STEERING FLOW DEVELOPING ACROSS SOUTH FLORIDA AS
TD FOUR LIFTS TO THE NORTHEAST. THE MAIN DIFFERENCE IN THEIR
SOLUTIONS IS THAT THE ECMWF KEEPS THE ATMOSPHERE FAIRLY DRY WHILE
THE GFS SHOWS A SIGNIFICANT INCREASE IN TROPICAL MOISTURE. AT ANY
RATE, IT APPEARS THAT THE HIGHEST POPS WILL RETURN TO THE INTERIOR
AND EAST COAST TOWARDS THE END OF THE WEEK AND INTO NEXT WEEKEND.
MARINE...
TROPICAL DEPRESSION FOUR IS FORECAST TO BECOME A TROPICAL STORM
OVER THE SOUTHEASTERN BAHAMAS LATER TODAY. ALTHOUGH CONFIDENCE
REMAINS BELOW NORMAL WITH REGARDS TO POTENTIAL TRACK AND
STRENGTH...THERE IS A CHANCE FOR STRONGER WINDS AND HIGHER SEAS IN
THE MONDAY NIGHT TO WEDNESDAY TIME FRAME IN THE ATLANTIC WATERS.
&&
.PRELIMINARY POINT TEMPS/POPS...
WEST PALM BEACH 91 79 90 79 / 10 10 50 20
FORT LAUDERDALE 93 80 92 81 / 10 10 40 30
MIAMI 92 79 90 78 / 10 10 40 30
NAPLES 92 78 94 78 / 30 30 50 30
&&
.MFL WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
AM...NONE.
GM...NONE.
&&
$$
SHORT TERM...57/DG
LONG TERM....30/KOB
AVIATION...54/BNB
AREA FORECAST DISCUSSION
NWS MIAMI FL
1050 AM EDT SUN AUG 24 2014
.UPDATE...THE PWAT ON THE MIAMI SOUNDING THIS MORNING WAS
LOWER...1.54 INCHES WITH DRY AIR EVEN IN THE LOWER LEVELS. THIS
WILL LEAD TO LESS CONVECTION THAN TYPICAL. HRRR DELAYS DEVELOPMENT
AND HAS ALL CONVECTION WESTERN INTERIOR-GULF COAST AND NOT UNTIL
AFTER 3 PM AND CONTINUING WELL INTO THE EVENING. GIVEN THE DRIER
AIR, DELAYED DEVELOPMENT LOOKS REASONABLE AND THE WIND PATTERN
DOES SUGGEST A GULF COAST FOCUS...AND ALIGNED POPS AS SUCH WHICH
WAS GENERALLY IN LINE WITH THE INHERITED FORECAST BUT WITH SUBTLE
CHANGES.
TROPICAL STORM CRISTOBAL NEAR THE SE BAHAMAS IS FORECAST TO MOVE
NORTH NORTHWEST THRU WED, THEN TURN NORTHEAST. MODELS HAVE
SOLIDIFIED ON A TRACK EAST OF FLORIDA, SO ASIDE FROM AN INCREASING
RISK OF RIP CURRENTS ALONG THE ATLANTIC BEACHES AND INCREASING
SEAS OVER THE ATLANTIC, NO OTHER IMPACTS ARE EXPECTED BUT WE OF
COURSE WILL CONTINUE TO MONITOR ITS PROGRESS. /GREGORIA
&&
.PREV DISCUSSION... /ISSUED 721 AM EDT SUN AUG 24 2014/
AVIATION...
DRIER WEATHER WILL PREVAIL OVER SOUTH FLORIDA TODAY WITH NORTHEAST
WIND FLOW MOST OF THE TAF SITES. THE ONLY EXCEPTION TO THIS IS FOR
KAPF TAF SITE WHERE THE WIND FLOW WILL BECOME WESTERLY AFTER
17Z DUE TO THE WEST COAST SEA BREEZE PUSHING INLAND. SO WILL KEEP
THE WEATHER DRY AT ALL OF THE EAST COAST TAF SITES TODAY AND ONLY
VCSH AT KAPF TAF SITE AFTER 17Z. THE CEILING AND VIS WILL ALSO
REMAIN IN VFR CONDITIONS TODAY.
AVIATION...54/BNB
PREV DISCUSSION... /ISSUED 246 AM EDT SUN AUG 24 2014/
SHORT TERM (TODAY-TUESDAY)...
A LARGE MID LEVEL RIDGE CURRENTLY CENTERED OVER ARKANSAS WILL SLOWLY
SHIFT TO THE NORTHEAST THROUGH TUESDAY AS A STRONG TROUGH MOVES INTO
THE ATLANTIC OFF THE NEW ENGLAND COAST. THIS WILL MAINTAIN A
NORTHEAST STEERING FLOW ACROSS SOUTH FLORIDA BUT WITH PWAT
CONTINUING TO RUN BELOW THE LATE AUGUST AVERAGE SO ONLY SCATTERED
STORMS CAN BE EXPECTED OVER THE INTERIOR AND SOUTHWEST COAST.
TROPICAL DEPRESSION FOUR IS NOW OVER THE SOUTHEAST BAHAMAS AND THE
LATEST MODEL CONSENSUS IS TO KEEP THE SYSTEM WELL TO THE EAST OF THE
FLORIDA PENINSULA. THE LATEST GFS 00Z RUN ALSO IS MORE IN LINE WITH
THE ECMWF WHICH HAS CONSISTENTLY STEERED TD FOUR THROUGH OR JUST
EAST OF THE BAHAMA ISLAND CHAIN AND THEN NORTH INTO THE OPEN
ATLANTIC. SO DEPENDING ON WHAT STRENGTH THE DISTURBANCE EVENTUALLY
DEVELOPS, THE ONLY IMPACT WILL BE TO CREATE BUILDING SEAS OFF THE
PALM BEACH COAST AS NORTHEAST SWELLS BEGIN TO AFFECT THE COASTAL
WATERS. THE ONLY FLY IN THE OINTMENT WILL BE ON TUESDAY AS THE
TROUGH MOVES OUT OF THE PICTURE AS IT LIFTS TO THE NORTHEAST. THIS
WILL ALLOW THE STEERING FLOW EAST OF THE PENINSULA TO BECOME VERY
WEAK AND THE TROPICAL SYSTEM MAY DRIFT A LITTLE TO THE WEST. SO
RESIDENTS OF SOUTH FLORIDA SHOULD CONTINUE TO MONITOR THE LATEST
FORECASTS FROM NHC.
LONG TERM (WEDNESDAY-SATURDAY)...
THE GFS AND ECMWF ARE IN FAIR AGREEMENT IN THE EXTENDED PERIOD WITH
A SOUTHWEST TO WEST STEERING FLOW DEVELOPING ACROSS SOUTH FLORIDA AS
TD FOUR LIFTS TO THE NORTHEAST. THE MAIN DIFFERENCE IN THEIR
SOLUTIONS IS THAT THE ECMWF KEEPS THE ATMOSPHERE FAIRLY DRY WHILE
THE GFS SHOWS A SIGNIFICANT INCREASE IN TROPICAL MOISTURE. AT ANY
RATE, IT APPEARS THAT THE HIGHEST POPS WILL RETURN TO THE INTERIOR
AND EAST COAST TOWARDS THE END OF THE WEEK AND INTO NEXT WEEKEND.
MARINE...
TROPICAL DEPRESSION FOUR IS FORECAST TO BECOME A TROPICAL STORM
OVER THE SOUTHEASTERN BAHAMAS LATER TODAY. ALTHOUGH CONFIDENCE
REMAINS BELOW NORMAL WITH REGARDS TO POTENTIAL TRACK AND
STRENGTH...THERE IS A CHANCE FOR STRONGER WINDS AND HIGHER SEAS IN
THE MONDAY NIGHT TO WEDNESDAY TIME FRAME IN THE ATLANTIC WATERS.
&&
.PRELIMINARY POINT TEMPS/POPS...
WEST PALM BEACH 91 79 90 79 / 10 10 50 20
FORT LAUDERDALE 93 80 92 81 / 10 10 40 30
MIAMI 92 79 90 78 / 10 10 40 30
NAPLES 92 78 94 78 / 30 30 50 30
&&
.MFL WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
AM...NONE.
GM...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS COLUMBIA SC
806 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. SCATTERED/BROKEN AROUND 5K FT ARE 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.
&&
$$
AREA FORECAST DISCUSSION
NWS COLUMBIA SC
640 AM EDT SUN AUG 24 2014
.SYNOPSIS...
A WEAK BACK DOOR COLD FRONT ACROSS THE AREA THIS MORNING WILL PUSH
SOUTH OF THE REGION BY THIS AFTERNOON. A FEW SHOWERS ARE POSSIBLE
ALONG AND AHEAD OF THE FRONT. HIGH PRESSURE CENTERED OVER THE
NORTHEASTERN STATES WILL EXTEND INTO THE CAROLINA THROUGH MID WEEK
RESULTING IN FAIR WEATHER WITH NEAR NORMAL TEMPERATURES.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
UPPER LEVEL RIDGE CONTINUES CENTERED OVER THE MISSISSIPPI VALLEY.
UPPER TROUGH OFF THE NEW ENGLAND AND MID ATLANTIC COAST. WEAK
SURFACE COLD FRONT NEAR CAE AT 07Z WILL SLOWLY PUSH SOUTH OF THE
AREA BY THIS AFTERNOON. A FEW SHOWERS CAN BE EXPECTED ALONG AND
AHEAD OF THE FRONT MAINLY THIS MORNING...BUT LACK OF LOW LEVEL
CONVERGENCE...UPPER SUPPORT AND WEAK INSTABILITY WILL LIMIT
COVERAGE. RADAR AT 07Z SHOWING SOME CONVECTION IN THE
PIEDMONT. RAP AND HRRR SUGGEST LOW POPS IN MIDLANDS. STRONGER
CONVERGENCE WILL SHIFT INTO GEORGIA BY THIS AFTERNOON AND EXPECT
DECREASING THREAT OF RAIN BY 18Z. WEAK INSTABILITY SO THUNDER
THREAT LOW. CONSIDERABLE LOW CLOUDS EARLY THIS MORNING WITH BREAKS
DEVELOPING BY MIDDAY THEN DECREASING CLOUDINESS IN THE AFTERNOON
AS DRIER AIR FROM NORTH CAROLINA ADVECTS SOUTH INTO THE REGION.
SHOULD BE COOLER BEHIND FRONT THIS AFTERNOON WITH NORTHEAST
FLOW/WEAK COLD ADVECTION. MOS TEMPERATURES CLOSE AND
ACCEPTED...UPPER 80S AROUND 90.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH TUESDAY/...
HIGH PRESSURE OVER THE NORTHEASTERN STATES WILL BE BUILDING
SOUTHWEST INTO THE CAROLINAS THROUGH THE PERIOD. DRIER AIR
ADVECTING INTO THE REGION THIS EVENING WITH PRECIPITABLE WATER
DECREASING TO LESS THAN 1 INCH BY MONDAY AFTERNOON. DRY CONDITIONS
WITH SEASONABLE TEMPERATURES.
&&
.LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/...
HIGH PRESSURE WILL REMAIN OVER THE AREA FOR MUCH OF THE WEEK.
ANOTHER COLD FRONT WILL APPROACH THE AREA BY SATURDAY...WITH A
CHANCE OF SHOWERS AND THUNDERSTORMS FRIDAY INTO SATURDAY. COOLER
DRY AIR SETTLING IN WILL BRING NEAR NORMAL TEMPS...WITH MAX TEMPS
MAINLY IN THE UPPER 80S TO THE LOWER 90S. OVERNIGHT MINS WILL BE
65 TO 70 RISING INTO THE LOWER 70S LATER IN THE WEEK.
&&
.AVIATION /12Z SUNDAY THROUGH THURSDAY/...
VFR CONDITIONS THROUGH MUCH OF THE TAF PERIOD...WITH MVFR CIGS
POSSIBLE OVER THE NEXT COUPLE OF HOURS.
FRONTAL BOUNDARY ACROSS THE AREA WILL CONTINUE SLOWLY MOVING
SOUTHWARD TODAY AND BE SOUTH OF THE TAF SITES TONIGHT. MVFR CIGS
CURRENTLY OVER CAE/CUB/OGB WILL ALSO BE MOVING SOUTHWARD REACHING
AGS/DNL OVER THE NEXT HOUR OR SO. EXPECT CIGS TO BEGIN IMPROVING
BY MID MORNING WITH ALL SITES RETURNING TO VFR BY 15Z. CONDITIONS
WILL FURTHER IMPROVE THROUGH THIS EVENING AS SLIGHTLY COOLER AND
DRIER AIR BEHIND THE FRONT MOVES INTO THE TAF SITES. WINDS WILL
BE NORTHEASTERLY AROUND 8 KNOTS THROUGH 15Z...INCREASE TO 11
KNOTS WITH GUSTS TO 17 KNOTS BETWEEN 15 AND 23Z...FINALLY
SUBSIDING TO 8 KNOTS FOR THE REMAINDER OF THE PERIOD.
EXTENDED AVIATION OUTLOOK...NO SIGNIFICANT IMPACTS TO AVIATION
EXPECTED MONDAY THROUGH THURSDAY.
&&
.CAE WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
GA...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS COLUMBIA SC
302 AM EDT SUN AUG 24 2014
.SYNOPSIS...
A WEAK BACK DOOR COLD FRONT ACROSS THE AREA THIS MORNING WILL PUSH
SOUTH OF THE REGION BY THIS AFTERNOON. A FEW SHOWERS ARE POSSIBLE
ALONG AND AHEAD OF THE FRONT. HIGH PRESSURE CENTERED OVER THE
NORTHEASTERN STATES WILL EXTEND INTO THE CAROLINA THROUGH MID WEEK
RESULTING IN FAIR WEATHER WITH NEAR NORMAL TEMPERATURES.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
UPPER LEVEL RIDGE CONTINUES CENTERED OVER THE MISSISSIPPI VALLEY.
UPPER TROUGH OFF THE NEW ENGLAND AND MID ATLANTIC COAST. WEAK
SURFACE COLD FRONT NEAR CAE AT 07Z WILL SLOWLY PUSH SOUTH OF THE
AREA BY THIS AFTERNOON. A FEW SHOWERS CAN BE EXPECTED ALONG AND
AHEAD OF THE FRONT MAINLY THIS MORNING...BUT LACK OF LOW LEVEL
CONVERGENCE...UPPER SUPPORT AND WEAK INSTABILITY WILL LIMIT
COVERAGE. RADAR AT 07Z SHOWING SOME CONVECTION IN THE
PIEDMONT. RAP AND HRRR SUGGEST LOW POPS IN MIDLANDS. STRONGER
CONVERGENCE WILL SHIFT INTO GEORGIA BY THIS AFTERNOON AND EXPECT
DECREASING THREAT OF RAIN BY 18Z. WEAK INSTABILITY SO THUNDER
THREAT LOW. CONSIDERABLE LOW CLOUDS EARLY THIS MORNING WITH BREAKS
DEVELOPING BY MIDDAY THEN DECREASING CLOUDINESS IN THE AFTERNOON
AS DRIER AIR FROM NORTH CAROLINA ADVECTS SOUTH INTO THE REGION.
SHOULD BE COOLER BEHIND FRONT THIS AFTERNOON WITH NORTHEAST
FLOW/WEAK COLD ADVECTION. MOS TEMPERATURES CLOSE AND
ACCEPTED...UPPER 80S AROUND 90.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH TUESDAY/...
HIGH PRESSURE OVER THE NORTHEASTERN STATES WILL BE BUILDING
SOUTHWEST INTO THE CAROLINAS THROUGH THE PERIOD. DRIER AIR ADVECTING
INTO THE REGION THIS EVENING WITH PRECIPITABLE WATER DECREASING TO
LESS THAN 1 INCH BY MONDAY AFTERNOON. DRY CONDITIONS WITH
SEASONABLE TEMPERATURES.
&&
.LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/...
HIGH PRESSURE WILL REMAIN OVER THE AREA FOR MUCH OF THE WEEK. ANOTHER
COLD FRONT WILL APPROACH THE AREA BY SATURDAY...WITH A CHANCE OF
SHOWERS AND THUNDERSTORMS FRIDAY INTO SATURDAY. COOLER DRY AIR
SETTLING IN WILL BRING NEAR NORMAL TEMPS...WITH MAX TEMPS MAINLY IN
THE UPPER 80S TO THE LOWER 90S. OVERNIGHT MINS WILL BE 65 TO 70
RISING INTO THE LOWER 70S LATER IN THE WEEK.
&&
.AVIATION /07Z SUNDAY THROUGH THURSDAY/...
VFR CONDITIONS THROUGH MUCH OF THE TAF PERIOD...WITH EARLY MORNING
MVFR CIGS.
WEAK FRONTAL BOUNDARY CONTINUES TO SLOWLY CROSS THE REGION WITH A
FEW SHOWERS AROUND CLT AND SOUTH OF AGS/DNL. EXPECT SHOWERS TO
CONTINUE CROSSING THE AREA OVERNIGHT...HOWEVER WITH LIMITED
COVERAGE HAVE NOT INCLUDED IN TAFS ATTM. WITH THE BOUNDARY AND
MOISTURE OVER THE REGION CIGS WILL LOWER TO MVFR BETWEEN 10 AND
15Z WITH CIGS SLOWLY IMPROVING THROUGH THE AFTERNOON AS THE
BOUNDARY SLIDES SOUTH OF THE TAF SITES. WINDS WILL BE
NORTHEASTERLY AROUND 5 KNOTS THROUGH 15Z...INCREASE TO 11 KNOTS
WITH GUSTS TO 17 KNOTS BETWEEN 15 AND 23Z...FINALLY SUBSIDING TO 8
KNOTS FOR THE REMAINDER OF THE PERIOD.
EXTENDED AVIATION OUTLOOK...NO SIGNIFICANT IMPACTS EXPECTED.
&&
.CAE WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
GA...NONE.
&&
$$
AREA FORECAST DISCUSSION...UPDATED FOR AVIATION
NWS PEACHTREE CITY GA
140 AM EDT SUN AUG 24 2014
.UPDATE...
/ISSUED AT 1042 PM EDT SAT AUG 23 2014/
COMPLEX OF SHOWERS/TSTORMS OVER SRN KY/NRN TN WAS PROGRESSING SOUTH.
THIS AREA IS DIMINISHING IN SIZE AND COVERAGE...HOWEVER EACH RUN OF
THE HRRR BRINGS IT CLOSER TO THE GA BORDER AFTER MIDNIGHT. WILL
THEREFORE INCREASE POPS TO CHANCE POPS ACROSS EXTREME NORTH GA AFTER
MIDNIGHT. NO OTHER CHANGES PLANNED.
&&
.SHORT TERM /TONIGHT THROUGH SUNDAY NIGHT/...
/ISSUED AT 346 PM EDT SAT AUG 23 2014/
NO CHANGES PLANNED TO THE CURRENT HEAT ADVISORY HEADLINE THIS
AFTERNOON. TEMPERATURES ARE EXPECTED TO BE COOLER TOMORROW...SO NO
EXTENSION INTO SUNDAY IS PLANNED AT THIS TIME.
19Z SURFACE ANALYSIS SHOWS A WEAK TROUGH ACROSS NE GA...WHILE HIGH
PRESSURE IS CENTERED ACROSS THE GULF STATES. 500MB ANALYSIS SHOWS A
WEAK SHORTWAVE DIVING SOUTH ACROSS WESTERN GA THIS AFTERNOON. THIS
SHORTWAVE HAS HELPED INITIATE AND SUSTAIN SOME SCATTERED SHOWERS AND
THUNDERSTORMS ACROSS NORTHERN GA THIS AFTERNOON. LATEST RUNS OF THE
HRRR KEEP CONVECTION GOING...ESPECIALLY ACROSS NW GA...INTO THE
EVENING HOURS AS THE SHORTWAVE CONTINUES TO IMPACT THE CWFA. DO
EXPECT CONVECTION TO BEGIN DIMINISHING BY THE LATE EVENING.
MODELS HAVE BEEN PERSISTENT IN BRINGING A BACKDOOR FRONTAL BOUNDARY
INTO NE GA TOMORROW. THE SURFACE FLOW WILL SWITCH AROUND TO THE EAST
OVERNIGHT...AND LOW LEVEL MOISTURE WILL BEGIN TO INCREASE ALONG AND
JUST AHEAD OF THE APPROACHING BOUNDARY. MODELS HAVE ALSO BEEN VERY
CONSISTENT IN PRODUCING HIGH POPS FOR THIS PERIOD. WITH THE
INCREASED CLOUD COVER AND PRECIPITATION...TEMPERATURES ACROSS THE
NORTHERN CWFA WILL BE SEVERAL DEGREES COOLER THAN TODAYS READINGS.
TEMPERATURES ACROSS THE SOUTHERN CWFA WILL HEAVILY DEPEND UPON HOW
FAR SOUTH THE BOUNDARY MAKES IT. MADE SOME MINOR TWEAKS TO THE
PRECIP TIMING...BUT OVERALL...NO MAJOR CHANGES TO THE POPS.
MODELS ARE DIMINISHING PRECIP CHANGES DURING THE EVENING HOURS.
HAVE NOT MADE MANY CHANGES TO THE SUNDAY NIGHT PERIOD.
NLISTEMAA
.LONG TERM /MONDAY THROUGH SATURDAY/...
/ISSUED AT 346 PM EDT SAT AUG 23 2014/
PATTERN IN BEGINNING OF LONG TERM PERIOD DOMINATED BY LARGE
POSITIVELY TILTED UPPER RIDGE OVER ALL SOUTHERN AND EASTERN STATES
WITH TROUGH ON EITHER SIDE...ONE OVER WESTERN CONUS AND ANOTHER
HIGHLY POSITIVELY TILTED TROUGH IN THE WESTERN ATLANTIC
PARALLELING THE EAST COAST. 12Z MED RANGE MODELS EXPANDS SOUTH AND
EAST CONUS RIDGE THRU EARLY WED WHILE PIECE OF WESTERN ATLANTIC
TROUGH DIPS SOUTH TOWARDS DEVELOPING TROPICAL SYSTEM. QUITE A
COMPLICATED PATTERN AND MAKES FORECASTING TRACK OF INVEST 96L
PROBLEMATIC. BY THURS...PATTERN BECOMES MORE ZONAL WITH BROAD
TROUGH OVER THE CENTRAL US AND BROAD RIDGES OVER THE WEST AND
EAST. 12Z GFS IS SLOWER WITH THE CENTRAL US TROUGH WHICH GIVES
A MORE WESTERN TRACK TO 96L...WHICH BASED ON RECENT MODEL RUNS AND
CONTINUED HIGH PROBABILITIES FROM NHC OUTLOOKS WILL LIKELY BECOME
TS CRISTOBAL. 12Z ECMWF SLIGHTLY MORE NORTHERN TRACK BUT BOTH
MODELS COMING INTO SIGNIFICANTLY BETTER AGREEMENT.
AS LONG AS TRACK DOES NOT SHIFT DRAMATICALLY WEST AND SOUTH FROM
CURRENT TRACK...IMPACT TO THE AREA WILL BE MINIMAL WITH DEEP DRY
AIRMASS AND SLIGHTLY STRONGER SFC WINDS.
COULD SEE ISOLD SHRA/TSRA BY THURS-FRI AS SLOW-MOVING CENTRAL US
TROUGH APPROACHES REGION FROM THE WEST.
SNELSON
PREV LONG TERM DISCUSSION /SUNDAY NIGHT THROUGH FRIDAY/...
/ISSUED AT 347 AM EDT SAT AUG 23 2014/
UPPER RIDGE CONTINUES TO DOMINATE AT THE BEGINNING OF THE
EXTENDED...WHILE SFC RIDGE BUILDS ACROSS THE MID ATLANTIC AND
DOWN THE APPALACHIANS. WITH THE PSEUDO WEDGE BUILDING IN...WINDS
BECOME EASTERLY AND CLOUD COVERAGE REMAINS BKN AT LEAST INITIALLY.
CLOUD COVERAGE DOES HELP TO KEEP TEMPS ON THE COOLER SIDE ON
MONDAY. DRIER AIR MOVES IN FOR THE FIRST HALF OF THE WEEK /BEHIND
THE BACKDOOR FRONT/. WITH THIS...DO NOT HAVE MOISTURE AROUND FOR
MUCH IN TERMS OF PRECIP AND THUS HAVE LIMITED POPS TO NO MENTION
OR SLIGHT CHANCE. DIFFERENCES EXIST BETWEEN THE GFS AND ECMWF IN
THE SECOND HALF THE OF THE EXTENDED. GFS BRINGS A COLD FRONT INTO
THE AREA ON FRIDAY...WHILE THE ECMWF KEEPS AN UPPER RIDGE ACROSS
THE SOUTHEAST. HAVE TENDED MORE TOWARDS THE GFS AND SHOWN AN
INCREASE IN CLOUDS/PRECIP FOR FRIDAY ASSOCIATED WITH THE FRONT.
DIFFERENCES ALSO EXIST STILL WITH HOW THE MODELS ARE HANDLING THE
POTENTIAL TROPICAL SYSTEM NEXT WEEK. GFS REMAINS FURTHER WEST AND
SLOWER WHILE THE ECMWF IS FURTHER EAST /ALTHOUGH LATEST RUN IS
WEST OF PREVIOUS RUN/ AND FASTER. NEITHER 00Z SOLUTION BRINGS
IMPACTS TO THE CWA...BUT REGARDLESS...STILL FAR OUT IN THE
FORECAST AND ITS SOMETHING THAT NEEDS TO BE WATCHED AS WE HEAD
INTO NEXT WEEK.
11
&&
.AVIATION...
06Z UPDATE...
BACK DOOR FRONT WILL ENTER NORTHEAST GA BY 09Z... THEN PUSH SOUTH OF
ATL BY 12-14Z... THEN SOUTH OF CSG AND MCN BY 15-16Z THIS MORNING.
EXPECT WINDS TO SHIFT NE AHEAD OF THE FRONT THEN MID LEVEL CIGS TO
SPREAD IN WITH OR JUST BEHIND THE FRONT. COULD SEE OCNL LOWER MVFR
CIGS WITH ANY ASSOCIATED MORNING SHOWERS ACTIVITY. MODELS CONTINUE
TO SUGGEST THE POTENTIAL FOR ISOLATED TO SCATTERED THUNDERSTORMS
BEHIND THE FRONT... SO WILL CONTINUE TO SHOW TEMPO 18-22 -TSRA...
BUT THINKING THE MORE WIDESPREAD CONVECTION WILL BE SHOWERS...
EXCEPT MAYBE DOWN AROUND MCN AND CSG. WINDS STAY NORTHEAST AROUND
10-12KT TODAY WITH HIGHER GUSTS TO AROUND 16-18KTS. MID LEVEL CIGS
ARE EXPECTED TO LOWER TO MVFR LEVELS TONIGHT AROUND 09Z.
//ATL CONFIDENCE...06Z UPDATE...
HIGH CONFIDENCE ON WINDS... MEDIUM CONFIDENCE ON ALL OTHER ELEMENTS.
39
&&
.PRELIMINARY POINT TEMPS/POPS...
ATHENS 74 89 70 87 / 40 60 40 10
ATLANTA 76 90 72 86 / 30 60 40 20
BLAIRSVILLE 68 83 66 82 / 40 60 40 20
CARTERSVILLE 73 91 72 87 / 30 60 40 20
COLUMBUS 79 95 74 88 / 20 60 40 20
GAINESVILLE 73 87 70 84 / 40 60 40 20
MACON 77 94 72 88 / 20 60 40 10
ROME 74 92 73 88 / 40 60 40 20
PEACHTREE CITY 75 91 72 87 / 20 60 40 20
VIDALIA 77 93 72 89 / 20 60 50 5
&&
.FFC WATCHES/WARNINGS/ADVISORIES...
&&
$$
SHORT TERM...NLISTEMAA/39
LONG TERM....SNELSON
AVIATION...39
AREA FORECAST DISCUSSION
NWS POCATELLO ID
150 PM MDT SUN AUG 24 2014
.SHORT TERM...TONIGHT THROUGH WEDNESDAY. NEXT UPSTREAM TROUGH
DIGGING SSE THROUGH WRN WASHINGTON/OREGON EARLY THIS AFTERNOON WITH
WEAK TO MODEST AFTERNOON CONVECTION DEVELOPING DOWNSTREAM ACROSS THE
SE IDAHO MOUNTAINS. NUMERICAL MODELS NOT QUITE AS ENTHUSED AS
PREVIOUS RUNS IN DEVELOPING PRECIPITATION ACROSS THE AREA AS UPPER
LOW TAKES SHAPE OVER OREGON LATER THIS EVENING. GFS AND NAM STILL
SHOWING SIGNIFICANT DIFFERENCES IN THE TRACK AND PROGRESSION OF THE
UPPER LOW MONDAY THROUGH WEDNESDAY. THE NAM DRIVES THE LOW INTO NW
NEVADA MONDAY AFTERNOON AND THEN SLOWLY EAST TUESDAY AND WEDNESDAY
WITH ACCOMPANYING PRECIPITATION/CONVECTION SPREADING EAST ACROSS SE
IDAHO. THE GFS ON THE OTHER HAND...SWINGS THE LOW THROUGH SE OREGON
MONDAY AFTERNOON AND THEN EAST ALONG THE NEVADA/UTAH BORDER TUESDAY
AND INTO COLORADO/WYOMING BY NOON WEDNESDAY MUCH FASTER THAN THE
NAM. MAIN DIFFERENCE HERE IS OBVIOUSLY THE ONSET OF DRYING. HAVE
GENERALLY SPLIT THE DIFFERENCE FOR NOW HOLDING ON TO A CHANCE OF
SHOWERS ACROSS THE SE HIGHLANDS TUESDAY NIGHT/WEDNESDAY UNTIL THE
MODELS SHAKE OUT THE DISCONTINUITY.
.LONG TERM...WEDNESDAY NIGHT THROUGH NEXT SUNDAY. A TRANSIENT RIDGE
WILL SPREAD ACROSS THE AREA WEDNESDAY NIGHT WITH DRY CONDITIONS
PREVAILING THROUGH FRIDAY. THE GFS AND ECMWF CONTINUE TO DIFFER ON
WHETHER SUB-TROPICAL MOISTURE FROM HURRICANE MARIE WILL GET INJECTED
INTO THE NEXT INCOMING TROUGH FOR THE WEEKEND. HAVE MADE NO CHANGES
TO THE CURRENT FORECAST WHICH PROVIDES FOR AT LEAST A CLIMATOLOGICAL
MENTION OF PRECIPITATION...AGAIN UNTIL THE MODELS SHAKE OUT THE
DISCONTINUITY. HUSTON
&&
.AVIATION...ACTIVE WEATHER IS BRIEFLY ON HOLD AS SOUTHEAST IDAHO
SITS BETWEEN THE DEEP UPPER LOW THAT EXITED THE REGION LAST
NIGHT...AND A SECOND UPPER LOW CURRENTLY MAKING ITS WAY INTO THE PAC
NW. MOS GUIDANCE IS DOWNPLAYING CHANCES FOR SHOWERS/THUNDERSTORMS
TODAY. HRRR IS SUGGESTING CONVECTIVE DEVELOPMENT THIS AFTERNOON OVER
THE CENTRAL MOUNTAINS. THIS WILL MAINLY IMPACT KSUN TODAY. STRONGEST
FORCING WILL COME JUST AHEAD OF DEEPENING UPPER LOW BETWEEN 12Z AND
18Z TOMORROW. INCLUDED VCSH AT KSUN AND KBYI. SHOWERS MAY SPREAD
FURTHER INTO SOUTHEAST IDAHO...BUT MODEL CROSS-SECTIONS SUGGEST THIS
WILL OCCUR BEYOND THE TAF PERIOD. TERMINALS EXPECTED TO REMAIN VFR
THROUGH THE PERIOD. HINSBERGER
&&
.FIRE WEATHER...ANOTHER UPPER LOW WILL DROP INTO THE PAC NW TONIGHT
WITH SHOWERS AND ISOLATED THUNDERSTORMS EXPECTED TO SPREAD ACROSS
THE REGION TOMORROW. MODELS ARE TRENDING TOWARDS A SLOWER
PROGRESSION OF THE UPPER LOW...SO SHOWERS MAY LINGER INTO WEDNESDAY
BEFORE RIDGING SPREADS OVER THE AREA. FOCUS OF THE PRECIP WILL BE
PRIMARILY OVER THE MOUNTAINS. WITH RIDGING MOVING INTO THE REGION ON
WEDNESDAY...WE CAN EXPECT WARMER AND DRIER CONDITIONS. ANOTHER
PACIFIC WEATHER SYSTEM WILL MAKE LANDFALL ON FRIDAY. THIS SYSTEM MAY
TAP INTO MOISTURE FROM THE REMNANTS OF HURRICANE MARIE...WHICH WOULD
RESULT IN GREATER RAINFALL AMOUNTS ACROSS THE AREA. HINSBERGER
&&
.PIH WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
1016 PM CDT MON AUG 25 2014
.DISCUSSION...
710 PM CDT
THE FORECAST UPDATED TO REFLECT CURRENT STORM TRENDS AS WELL AS
TO ADD AREAS OF FOG TONIGHT. DO ENVISION CANCELLING THE SEVERE
THUNDERSTORM WATCH FOR THE REMAINDER OF THE CWA BY 8 PM.
AN AREA OF LOOSELY ORGANIZED STORMS CONTINUES TO PROPAGATE SLOWLY
SOUTHEAST WITH OCCASIONAL FINGERS OF SLIGHTLY BETTER WIND
SIGNATURES ON RADAR. VERY EFFICIENT RAINFALL WILL REMAIN THE
PRIMARY HAZARD WITH THESE AS THEY CROSS THROUGH SOUTHERN IROQUOIS
AND BENTON COUNTIES. 00Z RAOB AND VAD WIND PROFILE FROM ILX
INDICATE SOUTHWEST FLOW AT 15-20 KT BETWEEN 3000-6000 FT...ENOUGH
TO HOLD UP THE OUTFLOW BOUNDARY NEAR THE I-74 CORRIDOR FROM NEAR
PEORIA TO BLOOMINGTON NORMAL BASED ON RADAR TRENDS. THIS FLOW DOES
NOT LOOK STRONG ENOUGH TO DEVELOP MUCH CONVECTION NORTH OF
THAT...SO OVERALL EXPECTING A QUIET EVENING FOR MUCH OF THE
FORECAST AREA.
WATER VAPOR AND LATE DAY VISIBLE SATELLITE INDICATE A SHEARED
SHORT WAVE MOVING EAST-NORTHEAST NEAR DES MOINES. WITH MINIMAL
CONVERGENCE IN THE 800-900MB LAYER /BASICALLY AT THE BASE OF THE
ELEVATED INSTABILITY/...IT IS DIFFICULT TO SAY WHAT THIS FEATURE
WILL DO IN TERMS OF SHOWERS OR CONVECTION LATE TONIGHT. HIGH
RESOLUTION GUIDANCE DOES VARY GREATLY...HOWEVER USING A SHORT
RANGE ENSEMBLE APPROACH INDICATES OVERLAP ACROSS NORTHWEST INTO
NORTH CENTRAL IL LATE. FOR NOW DO CONTINUE THE CHANCE OF THUNDER
OVERNIGHT...WITH SOMEWHAT HIGHER POPS IN THAT AREA.
BECAUSE OF THE RAIN-COOLED MOIST AIR GOING INTO DARK...AREAS OF
FOG SEEM MORE PROBABLE BY AFTER MIDNIGHT...SOME OF WHICH MAY BE
DENSE GIVEN SUCH LOW T/TD SPREADS AT PRESENT.
MTF
//PREV DISCUSSION...
325 PM CDT
SHORT TERM...THROUGH EARLY TUESDAY MORNING...
FOR THE REMAINDER OF THE AFTERNOON...MAIN FOCUS WILL CONTINUE TO BE
TWO 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 MAY CONTINUE INTO EARLY THIS EVENING AS WELL...WITH
SOME POTENTIAL FOR A FORWARD-PROPAGATING MCS ACROSS MAINLY THE
SOUTHERN HALF OF THE FORECAST AREA. THIS WOULD BE MAINLY CAPABLE
OF WIND. AS THE THUNDERSTORM ACTIVITY DIMINISHES LATER 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...TUESDAY THROUGH MONDAY...
TUESDAY AND WEDNESDAY...
THE MAIN CHANGE TO THE FORECAST DURING THIS PERIOD WAS TO SHIFT
THE HIGHER CHANCES FOR STORMS SOUTH AS THE FRONTAL BOUNDARY
ITSELF LOOKS TO BE FURTHER SOUTH THAN EARLIER FORECAST...LIKELY
HELPED BY EPISODES OF CONVECTION SUCH AS THIS AFTERNOON. BECAUSE
OF THIS...CHANCES OF STORMS IN THIS PERIOD LOOK TO BE GREATER IN
THE SOUTHERN FORECAST AREA THAN THE NORTH. LAKE ADJACENT AREAS
ALSO LOOK TO BE INFLUENCED BY LAKE AIR ON TUESDAY...POSSIBLY EVEN
BY MORNING. BECAUSE OF THAT HAVE ADJUSTED TEMPERATURES DOWNWARD ON
TUESDAY...WITH THE POSSIBILITY OF 90 NOW BEING HARBORED ONLY TO THE
FAR SOUTH...ALTHOUGH LIKE TODAY IF CONVECTION OCCURS THAT CAN
GREATLY DISRUPT THINGS. LOWER 80S LOOK MORE LIKELY NORTH WITH
UPPER 70S NEAR THE LAKE SHORE.
THERE COULD BE ONGOING ELEVATED STORM ACTIVITY FROM IA INTO
NORTHWESTERN/WESTERN IL AT DAYBREAK TUESDAY MOVING EASTWARD...THOUGH
THE DEGREE OF COVERAGE IS UNCERTAIN. MUCH LIKE TODAY...IF THERE IS
ENOUGH ACTIVITY IT COULD JUST CONTINUE TO FESTER EAST-SOUTHEAST INTO
THE ILLINOIS FORECAST AREA AND THEN FEED ON THE INSTABILITY IN THE
FAR SOUTHEAST PART OF THE AREA. EVEN IF THAT WERE NOT TO PAN
OUT...SCATTERED DEVELOPMENT OF STORMS LOOKS FAVORED IN THE AFTERNOON
ALONG THE BOUNDARY WHICH SHOULD BE DRAPED FROM WEST-TO-EAST NEAR
INTERSTATE 80. ANY THUNDERSTORM ACTIVITY WILL BE SIMILAR TO MUCH IN
THE PAST WEEK...POSSESSING HEAVY RAIN POTENTIAL AND ISOLATED GUSTY
WIND CONCERNS.
CHANCES FOR STORMS CONTINUE WEDNESDAY...MAINLY SOUTH...BEFORE 850MB
FLOW TURNS BRIEFLY MORE NORTHWESTERLY WEDNESDAY NIGHT.
THURSDAY INTO THE WEEKEND...
THE BOUNDARY REMAINS FORECAST TO RETURN NORTHWARD AS A WARM
FRONT...POSSIBLY ON THURSDAY...IN RESPONSE TO AN UPPER LOW MOVING
EAST FROM THE CENTRAL ROCKIES. A SURFACE LOW AHEAD OF THIS IS
FORECAST TO LIFT NORTHEAST...BUT OVERALL THIS LOOKS TO BE SLOW GIVEN
THE UPPER LEVEL FEATURE IS CUTOFF. TAPPING BACK INTO THE MOIST AIR
MASS THAT WE ARE PRESENTLY IN...IT WOULD APPEAR SHOWER AND STORM
CHANCES WOULD SPREAD BACK NORTHWARD ACROSS THE AREA AND LAST THROUGH
MUCH OF THIS TIME...ALTHOUGH MOST FAVORED AS WE GET INTO THE
STRONGER LOW LEVEL JET/MOISTURE TRANSPORT...WHICH IS DIFFICULT TO
TIME AT THIS POINT. THE TEMPERATURE FORECAST IS LOW
CONFIDENCE...WITH HIGHS SYNOPTICALLY FAVORED IN THE 80S...ALTHOUGH
CONVECTIVE AND/OR LAKE COOLING POSSIBLE EVERY DAY.
MTF
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 03Z...
* SOUTHERLY WINDS BECOMING WESTERLY OVERNIGHT AND THEN NORTH
NORTHEAST TUESDAY...WITH FROPA.
* POSSIBLE MVFR CEILINGS/VIS LATE TONIGHT/EARLY TUESDAY MORNING.
* POSSIBLE SHRA/TSRA LATE TONIGHT/EARLY TUESDAY MORNING.
RODRIGUEZ
//DISCUSSION...UPDATED 00Z...
SHOWERS AND THUNDERSTORMS CONTINUE TO SLOWLY DRIFT SOUTH OF THE
TERMINALS EARLY THIS EVENING BUT IN THE WAKE...SEVERAL OUTFLOW
BOUNDARIES REMAIN. THIS IS PROVIDING VARIABLE WIND DIRECTIONS AND
WILL CONTINUE TO DO SO OVER THE NEXT COUPLE OF HOURS...BUT WITH
SPEEDS LIKELY REMAINING UNDER 10 KT. A TREND BACK TOWARDS A LIGHT
SOUTHERLY WIND WILL OCCUR BEFORE FRONT APPROACHES AND WINDS SHIFT
TOWARDS THE WEST LATER TONIGHT. VEERING WILL CONTINUE WITH FROPA
EARLY TUESDAY MORNING AS WINDS TURN NORTH AND THEN NORTHEAST LATER
IN THE MORNING...REMAINING THIS DIRECTION THROUGH THE REST OF THE
FORECAST PERIOD. FOG AND STRATUS OUT AHEAD OF THIS FRONT COULD
DEVELOP ONCE AGAIN TONIGHT...WITH SHOWERS AND THUNDERSTORMS
DEVELOPING ALONG AND AHEAD OF THIS FRONT. DEVELOPMENT INITIALLY
APPEARS TO BE BEST MORE TOWARDS RFD...BUT DO EXPECT ANY PRECIP TO
SHIFT EAST SOUTHEAST AS THIS FRONT DROPS SOUTH THROUGH MID MORNING
TUESDAY AND THEN PUSHING SOUTH OF THE TERMINALS INTO MID DAY.
RODRIGUEZ
//ORD AND MDW CONFIDENCE...UPDATED 03Z...
* MEDIUM CONFIDENCE WITH WIND SPEED/DIRECTION WITH FROPA.
* LOW MEDIUM CONFIDENCE WITH MVFR TRENDS LATE TONIGHT/EARLY
TUESDAY MORNING.
* MEDIUM CONFIDENCE WITH SHRA/TSRA TRENDS LATE TONIGHT/EARLY
TUESDAY MORNING.
RODRIGUEZ
//OUTLOOK FOR ORD/MDW FOR 12Z WEDNESDAY-12Z MONDAY...UPDATED 00Z...
WEDNESDAY...SLIGHT CHANCE OF TSRA.
THURSDAY...CHANCE OF TSRA.
FRIDAY...CHANCE OF TSRA.
SATURDAY...CHANCE OF TSRA.
SUNDAY...CHANCE OF TSRA.
RODRIGUEZ
&&
.MARINE...
315 PM CDT
SCATTERED STORMS THIS AFTERNOON HAVE DISRUPTED THE WINDS SOME
ACROSS THE FAR SOUTHERN PART OF LAKE MICHIGAN.
OTHERWISE...SOUTHERLY FLOW IS ANTICIPATED MUCH OF TONIGHT ACROSS
THE LAKE. DEW POINTS ARE NOT AS HIGH AS THEY HAVE BEEN BUT STILL
NEAR OR AT THE WATER TEMPERATURE...THUS POTENTIALLY LEADING TO
SOME PATCHY FOG. A COLD FRONT WILL MOVE ACROSS THE LAKE LATE
TONIGHT INTO TUESDAY MORNING...TURNING WINDS NORTHERLY. EVENTUALLY
THIS BOUNDARY WILL SHIFT BACK NORTH ACROSS THE LAKE MOST LIKELY ON
THURSDAY OR THURSDAY NIGHT. SOUTHERLY WINDS WILL THEN BE SEEN OVER
THE LAKE BEFORE LOW PRESSURE PASSES NEAR THE NORTHERN PART OF THE
LAKE SOMETIME EARLY THIS WEEKEND.
MTF
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...NONE.
&&
$$
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FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
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[top]
Area Forecast Discussion
NATIONAL WEATHER SERVICE LINCOLN IL
943 PM CDT Mon Aug 25 2014
.MESOSCALE DISCUSSION...
ISSUED AT 915 PM CDT MON AUG 25 2014
Outflow boundary from this afternoon and early evening storms has
shifted into south central thru southeast Illinois. Cold pool
has brought some gusty east to northeast winds along and just
behind the outflow boundary with a marked decrease in temps
and dew points. Quick look at the latest Nam-Wrf model indicates
the cool front will be located from near Danville southwest thru
Quincy by mid-morning Tuesday. With winds shifting into the
north behind the boundary coupled with more cloud cover and
possible showers and thunderstorms, it appears the apparent
temperatures across the north and northeast will not meet heat
advisory criteria. As a result, will go ahead and cancel the
heat advisory for our far west, north and northeast counties with
only a small portion of the heat advisory remaining near and south
of Champaign. No changes were made to the Excessive Heat warning
at this time. Will have an updated NPW out highlighting the areas
that will be dropped and will update the ZFP once again this
evening.
&&
.UPDATE...
ISSUED AT 822 PM CDT MON AUG 25 2014
Storms continue to slowly diminish early this evening and expect
that trend to continue over the next few hours as we lose daytime
heating and the storms track further south into the upper ridge.
Hi-res short term models providing mixed signals as to when
additional thunderstorms develop/move into our area late tonight
as a cold front edges slowly into western Illinois by morning.
Not very confident on any one solution at this point but it appears
the low level jet and 850 mb moisture convergence will be more
supportive of storms developing over Iowa late tonight and then
track into our west during the early morning hours. Series of
shortwaves expected to slowly break down the upper level ridge
and drag a frontal boundary south across our area early this
week, before the front heads back into our area late in the week
and into next week providing daily chances for showers and storms.
One more day of high heat and humidity levels on Tuesday before we
see a gradual downward trend in temps for the remainder of the week.
Zones have already been updated to reflect the cancellation of the
watch and timing trends with the showers and storms over east
central Illinois.
&&
.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 00Z TAFS through 00Z Tuesday evening)
ISSUED AT 625 PM CDT MON AUG 25 2014
Convection affecting areas from just east of Peoria to north of
Bloomington southeast towards Champaign. The cells have decreased
in intensity over the past hour and unless we have a merger/collision
with an outflow boundary or another cell, expect this gradual weakening
trend to continue. After the storms move out, the main threat overnight
looks to be with fog again with some low vsbys possible in the 09z-12z
time frame. A cold front currently out over central Iowa will drift
east and approach the region by Tuesday morning. Most of the short term
models suggest we may see an increasing threat for scattered showers
and storms with the front, especially across the northwest Tuesday
morning. Once we lose any fog or low cloudiness in the morning,
forecast soundings still suggest mainly VFR conditions into the
afternoon hours. Surface winds this evening near the storms will
be variable in direction but eventually most areas should see light
winds out of the southeast tonight and then switch into a northwest
direction in the morning across the north, and by afternoon in the
south. However, wind speeds will still be averaging less than 10 kts.
&&
.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 ILZ043>046-055-057.
&&
$$
MESOSCALE...SMITH
UPDATE...SMITH
SHORT TERM...BARNES
LONG TERM...AUTEN
AVIATION...SMITH
CORRECTED THE WATCH/WARNING/ADVISORY SECTION ABOVE
AREA FORECAST DISCUSSION...UPDATED
NWS CHICAGO/ROMEOVILLE IL
712 PM CDT MON AUG 25 2014
.DISCUSSION...
710 PM CDT
THE FORECAST UPDATED TO REFLECT CURRENT STORM TRENDS AS WELL AS
TO ADD AREAS OF FOG TONIGHT. DO ENVISION CANCELLING THE SEVERE
THUNDERSTORM WATCH FOR THE REMAINDER OF THE CWA BY 8 PM.
AN AREA OF LOOSELY ORGANIZED STORMS CONTINUES TO PROPAGATE SLOWLY
SOUTHEAST WITH OCCASIONAL FINGERS OF SLIGHTLY BETTER WIND
SIGNATURES ON RADAR. VERY EFFICIENT RAINFALL WILL REMAIN THE
PRIMARY HAZARD WITH THESE AS THEY CROSS THROUGH SOUTHERN IROQUOIS
AND BENTON COUNTIES. 00Z RAOB AND VAD WIND PROFILE FROM ILX
INDICATE SOUTHWEST FLOW AT 15-20 KT BETWEEN 3000-6000 FT...ENOUGH
TO HOLD UP THE OUTFLOW BOUNDARY NEAR THE I-74 CORRIDOR FROM NEAR
PEORIA TO BLOOMINGTON NORMAL BASED ON RADAR TRENDS. THIS FLOW DOES
NOT LOOK STRONG ENOUGH TO DEVELOP MUCH CONVECTION NORTH OF
THAT...SO OVERALL EXPECTING A QUIET EVENING FOR MUCH OF THE
FORECAST AREA.
WATER VAPOR AND LATE DAY VISIBLE SATELLITE INDICATE A SHEARED
SHORT WAVE MOVING EAST-NORTHEAST NEAR DES MOINES. WITH MINIMAL
CONVERGENCE IN THE 800-900MB LAYER /BASICALLY AT THE BASE OF THE
ELEVATED INSTABILITY/...IT IS DIFFICULT TO SAY WHAT THIS FEATURE
WILL DO IN TERMS OF SHOWERS OR CONVECTION LATE TONIGHT. HIGH
RESOLUTION GUIDANCE DOES VARY GREATLY...HOWEVER USING A SHORT
RANGE ENSEMBLE APPROACH INDICATES OVERLAP ACROSS NORTHWEST INTO
NORTH CENTRAL IL LATE. FOR NOW DO CONTINUE THE CHANCE OF THUNDER
OVERNIGHT...WITH SOMEWHAT HIGHER POPS IN THAT AREA.
BECAUSE OF THE RAIN-COOLED MOIST AIR GOING INTO DARK...AREAS OF
FOG SEEM MORE PROBABLE BY AFTER MIDNIGHT...SOME OF WHICH MAY BE
DENSE GIVEN SUCH LOW T/TD SPREADS AT PRESENT.
MTF
&&
.PREV DISCUSSION...
325 PM CDT
SHORT TERM...THROUGH EARLY TUESDAY MORNING...
FOR THE REMAINDER OF THE AFTERNOON...MAIN FOCUS WILL CONTINUE TO BE
TWO 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 MAY CONTINUE INTO EARLY THIS EVENING AS WELL...WITH
SOME POTENTIAL FOR A FORWARD-PROPAGATING MCS ACROSS MAINLY THE
SOUTHERN HALF OF THE FORECAST AREA. THIS WOULD BE MAINLY CAPABLE
OF WIND. AS THE THUNDERSTORM ACTIVITY DIMINISHES LATER 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...TUESDAY THROUGH MONDAY...
TUESDAY AND WEDNESDAY...
THE MAIN CHANGE TO THE FORECAST DURING THIS PERIOD WAS TO SHIFT
THE HIGHER CHANCES FOR STORMS SOUTH AS THE FRONTAL BOUNDARY
ITSELF LOOKS TO BE FURTHER SOUTH THAN EARLIER FORECAST...LIKELY
HELPED BY EPISODES OF CONVECTION SUCH AS THIS AFTERNOON. BECAUSE
OF THIS...CHANCES OF STORMS IN THIS PERIOD LOOK TO BE GREATER IN
THE SOUTHERN FORECAST AREA THAN THE NORTH. LAKE ADJACENT AREAS
ALSO LOOK TO BE INFLUENCED BY LAKE AIR ON TUESDAY...POSSIBLY EVEN
BY MORNING. BECAUSE OF THAT HAVE ADJUSTED TEMPERATURES DOWNWARD ON
TUESDAY...WITH THE POSSIBILITY OF 90 NOW BEING HARBORED ONLY TO THE
FAR SOUTH...ALTHOUGH LIKE TODAY IF CONVECTION OCCURS THAT CAN
GREATLY DISRUPT THINGS. LOWER 80S LOOK MORE LIKELY NORTH WITH
UPPER 70S NEAR THE LAKE SHORE.
THERE COULD BE ONGOING ELEVATED STORM ACTIVITY FROM IA INTO
NORTHWESTERN/WESTERN IL AT DAYBREAK TUESDAY MOVING EASTWARD...THOUGH
THE DEGREE OF COVERAGE IS UNCERTAIN. MUCH LIKE TODAY...IF THERE IS
ENOUGH ACTIVITY IT COULD JUST CONTINUE TO FESTER EAST-SOUTHEAST INTO
THE ILLINOIS FORECAST AREA AND THEN FEED ON THE INSTABILITY IN THE
FAR SOUTHEAST PART OF THE AREA. EVEN IF THAT WERE NOT TO PAN
OUT...SCATTERED DEVELOPMENT OF STORMS LOOKS FAVORED IN THE AFTERNOON
ALONG THE BOUNDARY WHICH SHOULD BE DRAPED FROM WEST-TO-EAST NEAR
INTERSTATE 80. ANY THUNDERSTORM ACTIVITY WILL BE SIMILAR TO MUCH IN
THE PAST WEEK...POSSESSING HEAVY RAIN POTENTIAL AND ISOLATED GUSTY
WIND CONCERNS.
CHANCES FOR STORMS CONTINUE WEDNESDAY...MAINLY SOUTH...BEFORE 850MB
FLOW TURNS BRIEFLY MORE NORTHWESTERLY WEDNESDAY NIGHT.
THURSDAY INTO THE WEEKEND...
THE BOUNDARY REMAINS FORECAST TO RETURN NORTHWARD AS A WARM
FRONT...POSSIBLY ON THURSDAY...IN RESPONSE TO AN UPPER LOW MOVING
EAST FROM THE CENTRAL ROCKIES. A SURFACE LOW AHEAD OF THIS IS
FORECAST TO LIFT NORTHEAST...BUT OVERALL THIS LOOKS TO BE SLOW GIVEN
THE UPPER LEVEL FEATURE IS CUTOFF. TAPPING BACK INTO THE MOIST AIR
MASS THAT WE ARE PRESENTLY IN...IT WOULD APPEAR SHOWER AND STORM
CHANCES WOULD SPREAD BACK NORTHWARD ACROSS THE AREA AND LAST THROUGH
MUCH OF THIS TIME...ALTHOUGH MOST FAVORED AS WE GET INTO THE
STRONGER LOW LEVEL JET/MOISTURE TRANSPORT...WHICH IS DIFFICULT TO
TIME AT THIS POINT. THE TEMPERATURE FORECAST IS LOW
CONFIDENCE...WITH HIGHS SYNOPTICALLY FAVORED IN THE 80S...ALTHOUGH
CONVECTIVE AND/OR LAKE COOLING POSSIBLE EVERY DAY.
MTF
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 22Z...
* LINGERING SHRA OVER THE NEXT 1-2 HOURS.
* SOUTHWEST WINDS BECOMING MORE SOUTH SOUTHEAST OVER THE NEXT 1-2
HOURS.
* 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/RODRIGUEZ
//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 22Z...
* HIGH CONFIDENCE WITH LINGERING SHRA IN THE NEAR TERM.
* MEDIUM CONFIDENCE WITH WIND SPEED/DIRECTION IN THE NEAR TERM.
* LOW CONFIDENCE ON ADDITIONAL TSRA OVERNIGHT/EARLY TUE MORNING.
* 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...
315 PM CDT
SCATTERED STORMS THIS AFTERNOON HAVE DISRUPTED THE WINDS SOME
ACROSS THE FAR SOUTHERN PART OF LAKE MICHIGAN.
OTHERWISE...SOUTHERLY FLOW IS ANTICIPATED MUCH OF TONIGHT ACROSS
THE LAKE. DEW POINTS ARE NOT AS HIGH AS THEY HAVE BEEN BUT STILL
NEAR OR AT THE WATER TEMPERATURE...THUS POTENTIALLY LEADING TO
SOME PATCHY FOG. A COLD FRONT WILL MOVE ACROSS THE LAKE LATE
TONIGHT INTO TUESDAY MORNING...TURNING WINDS NORTHERLY. EVENTUALLY
THIS BOUNDARY WILL SHIFT BACK NORTH ACROSS THE LAKE MOST LIKELY ON
THURSDAY OR THURSDAY NIGHT. SOUTHERLY WINDS WILL THEN BE SEEN OVER
THE LAKE BEFORE LOW PRESSURE PASSES NEAR THE NORTHERN PART OF THE
LAKE SOMETIME EARLY THIS WEEKEND.
MTF
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...NONE.
&&
$$
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FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
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Area Forecast Discussion
NATIONAL WEATHER SERVICE LINCOLN IL
631 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 00Z TAFS through 00Z Tuesday evening)
ISSUED AT 625 PM CDT MON AUG 25 2014
Convection affecting areas from just east of Peoria to north of
Bloomington southeast towards Champaign. The cells have decreased
in intensity over the past hour and unless we have a merger/collision
with an outflow boundary or another cell, expect this gradual weakening
trend to continue. After the storms move out, the main threat overnight
looks to be with fog again with some low vsbys possible in the 09z-12z
time frame. A cold front currently out over central Iowa will drift
east and approach the region by Tuesday morning. Most of the short term
models suggest we may see an increasing threat for scattered showers
and storms with the front, especially across the northwest Tuesday
morning. Once we lose any fog or low cloudiness in the morning,
forecast soundings still suggest mainly VFR conditions into the
afternoon hours. Surface winds this evening near the storms will
be variable in direction but eventually most areas should see light
winds out of the southeast tonight and then switch into a northwest
direction in the morning across the north, and by afternoon in the
south. However, wind speeds will still be averaging less than 10 kts.
&&
.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...SMITH
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
114 PM CDT SUN AUG 24 2014
.DISCUSSION...
330 AM...FORECAST CONCERNS INCLUDE HIGH TEMPS AND HEAT INDICES
TODAY AND MONDAY AND THEN THUNDERSTORMS CHANCES MONDAY MORNING
THROUGH SATURDAY.
IN THE SHORT TERM...A WEAK UPPER WAVE IS VERY SLOWLY MOVING
NORTHEAST ACROSS SOUTHERN LAKE MICHIGAN. SHOWERS AND PERHAPS AN
ISOLATED THUNDERSTORM WILL BE POSSIBLE THROUGH MID MORNING BUT
REMAIN OVER THE LAKE WITH A FEW SPRINKLES OR A SHOWER OVER FAR
NORTHEAST IL THROUGH DAYBREAK.
FOG HAS SO FAR REMAINED PATCHY BUT AS MID/HIGH CLOUDS BEGIN TO
SCATTER FROM WEST TO EAST...FURTHER FOG DEVELOPMENT AND POSSIBLY
SOME DENSE FOG WILL BE POSSIBLE AND WILL ONCE AGAIN NEED TO
MONITOR TRENDS. FOG DEVELOPMENT IS POSSIBLE AGAIN TONIGHT THOUGH
CONFIDENCE REGARDING DENSE FOG IS LOW.
WITH THE UPPER RIDGE BUILDING ACROSS THE AREA TODAY AND TONIGHT...
PRECIP CHANCES APPEAR TO REMAIN BELOW MENTIONABLE POPS. GIVEN THE
VERY MOIST LOW LEVELS...A STRAY THUNDERSTORM CAN/T BE COMPLETELY
RULED OUT BUT HAVE MAINTAINED DRY FORECAST AND WITH THE LACK OF
PRECIP AND CLOUD COVER...THERMAL PROFILES SUGGEST HIGH TEMPS
REACHING THE UPPER 80S TO AROUND 90...COOLER NEAR THE LAKE. WITH
DEWPOINTS REBOUNDING BACK INTO THE LOWER/MID 70S THIS AFTERNOON...
THIS WOULD YIELD HEAT INDICES GENERALLY IN THE UPPER 90S TO AROUND
100. THUS NO HEAT ADVISORY FOR TODAY. IF TEMPERATURES DID WARM A
FEW DEGREES ABOVE EXPECTED VALUES...COULD TAG ADVISORY CRITERIA IN
THE FAR SOUTH.
THERMAL PROFILES WARM A FEW DEGREES ON MONDAY WITH LOW TEMPS
TONIGHT PERHAPS A FEW DEGREES WARMER. WITH ENOUGH SUNSHINE THROUGH
EARLY AFTERNOON...HIGH TEMPERATURES SHOULD REACH LOWER 90S ALL
AREAS...PERHAPS A FEW LOCATIONS TAGGING MID 90S. SOUTHWESTERLY
WINDS NOW APPEARS STRONG ENOUGH TO PREVENT ANY LAKE COOLING...SO
HOT TEMPS ARE EXPECTED TO REACH THE BEACHES/LAKESHORE. DEWPOINTS
REMAIN IN THE LOWER/MID 70S. THIS COMBINATION PRODUCES HEAT
INDICES 100 NORTH TO 106 SOUTH...WHICH WOULD MEET ADVISORY
CRITERIA OVER AT LEAST THE SOUTHERN HALF OR THIRD OF THE CWA.
STILL 3RD PERIOD FROM THIS DISTANCE SO NOT PLANNING ANY HEADLINES
THIS MORNING BUT WILL HIGHLIGHT HEAT/HUMIDITY WITH AN SPS FOR THE
ENTIRE AREA.
A FRONTAL BOUNDARY WILL MOVE ACROSS THE MIDWEST TONIGHT AND MONDAY
AND SAG INTO THE IL/WI STATE LINE REGION MONDAY NIGHT. DISSIPATING
CONVECTION AHEAD OF THIS FRONT COULD POTENTIALLY SAG INTO THE FAR
NORTHERN CWA MONDAY MORNING WITH A LITTLE BETTER CHANCE OF
THUNDERSTORMS MONDAY AFTERNOON...MAINLY ACROSS THE NORTHERN CWA...
AS THE BOUNDARY SLOWLY DRIFTS SOUTH. CONFIDENCE ISN/T HIGH WITH
CONVECTIVE TRENDS DURING THIS TIME AND ITS POSSIBLE THAT THIS
ENTIRE PERIOD COULD REMAIN DRY. SHOULD THUNDERSTORMS BECOME MORE
WIDESPREAD AND/OR OCCUR SOONER...HIGH TEMPERATURES COULD BE TOO
WARM ON MONDAY...PARTICULARLY ACROSS THE NORTH.
THIS FRONTAL BOUNDARY THEN STALLS ACROSS OR NEAR THE AREA THROUGH
MID WEEK. DIFFICULT AT THIS POINT TO NARROW DOWN TIMING OR
LOCATION OF CONVECTION BEYOND MONDAY NIGHT AND THUS CHANCE POPS
FOR THE REMAINDER OF THE PERIOD WITH PERHAPS A SLIGHTLY BETTER
CHANCE FOR OVERNIGHT ACTIVITY TUESDAY NIGHT AND AGAIN WEDNESDAY
NIGHT. DESPITE LOW CONFIDENCE IN TIMING...WHEREVER THUNDERSTORMS
DO DEVELOP...THEY WILL BE EFFICIENT RAIN PRODUCERS AS DEWPOINTS IN
THE 70S ARE RAINED OUT. HEAVY RAIN AND LOCALIZED FLASH FLOODING
WILL BE POSSIBLE AT ANY TIME WITH ANY THUNDERSTORMS THROUGH THE
PERIOD. CMS
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 18Z...
* SOUTHEAST WINDS BECOMING EAST AT 20-21Z WITH LAKE BREEZE. WIND
SPEEDS AROUND 10 KT.
* MVFR VSBY IN FOG EXPECTED 08-14Z MONDAY.
* SCATTERED THUNDERSTORMS POSSIBLE LATE MONDAY.
ED F
//DISCUSSION...UPDATED 18Z...
WEAK SOUTHEAST FLOW OVER THE AREA THIS AFTERNOON AHEAD OF A COLD
FRONT OVER WESTERN MINNESOTA AND WESTERN IOWA. WEAK GRADIENT WILL
ALLOW LAKE BREEZE TO PUSH INLAND... WHICH IS ALREADY EVIDENT ON
TERMINAL DOPPLER RADARS. EXPECT WINDS TO TURN MORE EAST IN THE
20-21Z HOUR WITH SUSTAINED WINDS AROUND 10 KTS AFTER IT PUSHES THROUGH.
OTHERWISE FAIR WEATHER ALBEIT WARM AND HUMID WITH SCATTERED CU
BASES 025-030 EXPECTED THROUGH THE REMAINDER OF THE AFTERNOON.
WINDS EASE OFF TOWARD SUNSET (00-01Z) AND WITH RESIDUAL LOW
LEVEL MOISTURE COMBINED WITH WEAK SOUTHERLY FLOW EXPECT LIGHT FOG
TO DEVELOP OVERNIGHT. MAY SEE LOCALLY DENSE FOG PATCHES WEST OF
THE CHICAGO METRO. HOWEVER WITH A CONTINUED WEAK SOUTHERLY FLOW...
WINDS SHOULD STAY UP JUST ENOUGH TO INHIBIT WIDESPREAD DENSE
FOG... AND URBAN HEAT IMPACTS WILL FURTHER MINIMIZE IMPACT AT ORD
AND MDW.
OUTLOOK FOR MONDAY INCLUDES INCREASING HIGH CLOUDS AHEAD OF RAIN
AND STORMS OFF TO THE WEST WITH SOUTHERLY FLOW INCREASING TO
AROUND 10 KTS DURING THE AFTERNOON. THUNDERSTORM CHANGES INCREASE
FROM THE NORTH AND WEST AHEAD OF THE APPROACHING COLD FRONT THROUGH
THE AFTERNOON AND EVENING.
ED F
//ORD AND MDW CONFIDENCE...UPDATED 18Z...
* MEDIUM TO HIGH CONFIDENCE IN WIND DIRECTION CHANGE / LAKE BREEZE
TIMING THIS AFTERNOON. MEDIUM TO HIGH CONFIDENCE IN SPEEDS
AROUND 10 KT AFTER WINDS BECOME EAST.
* MEDIUM CONFIDENCE IN MVFR VSBYS IN FOG EARLY MORNING MONDAY.
* LOW TO MEDIUM CONFIDENCE IN TSTMS LATE MONDAY AFTERNOON.
ED F
//OUTLOOK FOR ORD/MDW FOR 00Z TUESDAY-12Z SUNDAY...UPDATED 12Z...
MONDAY NIGHT THROUGH SATURDAY...PERIODIC CHANCES FOR SHRA/TSRA AND
MVFR.
MDB
&&
.MARINE...
245 AM CDT
LOW PRESSURE CONTINUES TO MOVE NORTHWARD ACROSS THE DAKOTAS WHILE
HIGH PRESSURE OVER SOUTHEASTERN ONTARIO AND SOUTHERN QUEBEC MOVES
SOUTHWARD INTO NEW ENGLAND. A BETTER ORGANIZED PRESSURE GRADIENT
THAN WE HAVE OBSERVED THE PAST FEW DAYS IS IN PLACE ACROSS THE
AREA LEADING TO A BIT STEADIER SOUTHEAST TO EAST WIND ACROSS THE
LAKE TODAY WHICH WILL TURN SOUTHEAST THEN SOUTH TONIGHT AND MONDAY
MORNING. THE LOW WILL TURN EASTWARD ACROSS NORTHERN ONTARIO MONDAY
MORNING AND DRAG A COOL FRONTAL BOUNDARY SOUTHWARD. THE FRONT WILL
BE SLOW TO MOVE DOWN THE LAKE TUESDAY AND WEDNESDAY AND LOOKS TO
STALL OUT SOMEWHERE OVER OR JUST SOUTH OF THE LAKE GOING INTO
WEDNESDAY. AN UPPER TROUGH WILL BE MOVING ONSHORE OVER THE PACIFIC
NORTHWEST SUNDAY NIGHT AND DRIVE LOW PRESSURE DEVELOPMENT ACROSS
THE CENTRAL PLAINS. THIS LOW WILL TRACK NORTHEAST OVER OR NEAR THE
LAKE INTO FRIDAY WITH THE MAIN STORM TRACK SETTING UP ACROSS THE
LAKE THURSDAY AND FRIDAY. WIND SPEEDS FROM EARLY NEXT WEEK ONWARD
WILL BE TRICKY GIVEN THE PRESENCE OF THE FRONT BUT EXPECT
GENERALLY EAST TO NORTHEAST WINDS NORTH OF THE FRONT AND SOUTHERLY
TO THE SOUTH. THERE ARE STILL HINTS THAT COLDER AIR WILL SPILL IN
BEHIND THE FRONT BRINGING A PERIOD OF STRONGER WINDS MID TO LATE
WEEK.
MDB
&&
.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
1247 PM CDT Sun Aug 24 2014
.UPDATE...
ISSUED AT 1024 AM CDT SUN AUG 24 2014
15z/10am surface analysis shows a weak frontal boundary across
central Illinois, generally extending from near Galesburg to just
south of Lawrenceville. Despite presence of boundary, very little
in the way of cloud cover is noted on visible satellite. Most of
the clouds are further north and east across northern Illinois
arcing southeastward into Indiana. Models are showing a mostly dry
forecast today thanks to upper ridging that has sharpened over the
Midwest. NAM is completely dry, but both the HRRR and Rapid Refresh
hint at isolated convection this afternoon across south-central
Illinois. Do not see much support for this at the moment, but will
maintain just slight chance PoPs across the far southeast KILX
CWA. Main story today will be the hot and humid conditions. With
mostly sunny skies, afternoon high temperatures will reach the
lower 90s across the board, with heat index values exceeding 105
degrees along/south of a Lincoln to Marshall line.
&&
.SHORT TERM...(Today and tonight)
ISSUED AT 251 AM CDT SUN AUG 24 2014
The expected extended period of heat covering a total of four days
has prompted a move to upgrade the heat advisory to a heat warning
in our southern tier of counties. Even if some areas in the warning
do not hit 110F heat index any day, the extended period of
accumulative heat takes the toll as if you are hitting the higher
110F+ readings. Dewpoints climbed well above any guidance numbers
across our S-SE counties Saturday afternoon, with 80 and 81F
dewpoints reported. Guidance showed 75-76F Td for those same areas.
So heat index readings climbed over warning criteria of 110F even on
Saturday, when thoughts were that they would remain around 105F.
Slightly hotter conditions are expected for today and Monday, and if
dewpoints climb to where they were on Saturday, we should reach near
110F heat indices in our S-SE counties. Depending on how the thicker
cirrus clears today, highs should reach into the lower 90s in most
areas, with some mid 90s possible in the south-southwest where the
thermal ridge will begin to build into IL from the SW.
Thunderstorm chances will be more limited today than Saturday,
somewhat due to the increasing mid level temps which help to cap any
updrafts. Due to the orientation and position of the upper level
ridge and residual outflow boundary near our SE counties, we kept
afternoon 20 percent chance PoPs only SE of I-70 for this afternoon
and early evening. The ridge axis up the Mississippi River Valley
should guide that storm track to our N-NW. Very heavy rainfall and
gusty winds will be possible from any storm again today, due to very
high moisture content in the airmass and potential moisture loading
in any storms.
With clearing skies and light wind later tonight, fog will likely
develop into early Monday morning. The restriction to visibility
should not become dense, based on forecast soundings, but local
areas could drop below 1/2 mile near the Indiana border.
&&
.LONG TERM...(Monday through Saturday)
ISSUED AT 251 AM CDT SUN AUG 24 2014
Initial concern with this period continues to be with the heat.
Thermal ridge axis to extend over the CWA through Tuesday, with the
frontal boundary getting hung up to our north. This should result in
high temperatures of 91-95 over the entire forecast area Monday and
Tuesday. Will issue a heat advisory for Monday from around Peoria
southeast to Danville and Paris, as these areas should see heat
index values around 105, and will maintain the advisory around
Rushville and Havana. Will hold off on adding Tuesday at this point,
as there is some question about the amount of clouds and convection
potentially affecting this area.
Regarding that convection, am thinking that Monday and Monday night
should largely be dry, with MCS activity along the front to our
northwest. Most of the evening models show the MCS or its remnants
tracking southeast somewhat on Tuesday, and have PoP`s mentioned
roughly north of I-72. Additional MCS activity likely to form to our
north/northwest Tuesday night as well. The ECMWF/GEM start to sink
the frontal boundary down into our area by this point, while the GFS
has the warm front all the way into southern Wisconsin. Leaned
toward the former solutions and increase the PoP`s from northwest to
southeast Tuesday night into Wednesday.
The forecast beyond Wednesday remains a bit murky. The GFS is
slowing down a bit but remains much more progressive with a broad
trough moving eastward into the Mississippi Valley. The ECMWF and
GEM only slowly break down the ridge and pretty much don`t get the
wave even into the area until mid to late weekend. The tropical
system moving offshore of the East Coast doesn`t help matters
either. Have kept most of the PoP`s focused on the period through
Friday, but confidence in this part of the forecast is lower than
usual.
&&
.AVIATION...(For the 18Z TAFS through 18Z Monday afternoon)
ISSUED AT 1247 PM CDT SUN AUG 24 2014
Thanks to strong upper ridge axis in place across the region,
mostly sunny skies will prevail across central Illinois this
afternoon. Latest visible satellite imagery is showing SCT-BKN Cu
developing along/east of the I-57 corridor. Based on satellite
trends and Cu-rule, have included SCT clouds at around 2500ft at
both KBMI and KCMI accordingly. Main aviation question is whether
or not fog will develop tonight. Very little fog was observed last
night: however, airmass will remain quite moist and low-level winds
will be light from the S/SE overnight. Forecast soundings and
numeric guidance suggest at least patchy fog will form late
tonight, so have included a minimal reduction in visby at all
terminals between 09z and 13z. Introduced the lowest visbys down
to 3sm at both KBMI and KCMI where fog occurred last night.
&&
.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 from Noon to 7 PM CDT Monday FOR ILZ029-031-037-
038-043>046-055-057.
HEAT ADVISORY until 7 PM CDT Monday FOR ILZ036-040-041.
&&
$$
UPDATE...BARNES
SHORT TERM...SHIMON
LONG TERM...GEELHART
AVIATION...BARNES
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
1117 AM CDT SUN AUG 24 2014
.DISCUSSION...
330 AM...FORECAST CONCERNS INCLUDE HIGH TEMPS AND HEAT INDICES
TODAY AND MONDAY AND THEN THUNDERSTORMS CHANCES MONDAY MORNING
THROUGH SATURDAY.
IN THE SHORT TERM...A WEAK UPPER WAVE IS VERY SLOWLY MOVING
NORTHEAST ACROSS SOUTHERN LAKE MICHIGAN. SHOWERS AND PERHAPS AN
ISOLATED THUNDERSTORM WILL BE POSSIBLE THROUGH MID MORNING BUT
REMAIN OVER THE LAKE WITH A FEW SPRINKLES OR A SHOWER OVER FAR
NORTHEAST IL THROUGH DAYBREAK.
FOG HAS SO FAR REMAINED PATCHY BUT AS MID/HIGH CLOUDS BEGIN TO
SCATTER FROM WEST TO EAST...FURTHER FOG DEVELOPMENT AND POSSIBLY
SOME DENSE FOG WILL BE POSSIBLE AND WILL ONCE AGAIN NEED TO
MONITOR TRENDS. FOG DEVELOPMENT IS POSSIBLE AGAIN TONIGHT THOUGH
CONFIDENCE REGARDING DENSE FOG IS LOW.
WITH THE UPPER RIDGE BUILDING ACROSS THE AREA TODAY AND TONIGHT...
PRECIP CHANCES APPEAR TO REMAIN BELOW MENTIONABLE POPS. GIVEN THE
VERY MOIST LOW LEVELS...A STRAY THUNDERSTORM CAN/T BE COMPLETELY
RULED OUT BUT HAVE MAINTAINED DRY FORECAST AND WITH THE LACK OF
PRECIP AND CLOUD COVER...THERMAL PROFILES SUGGEST HIGH TEMPS
REACHING THE UPPER 80S TO AROUND 90...COOLER NEAR THE LAKE. WITH
DEWPOINTS REBOUNDING BACK INTO THE LOWER/MID 70S THIS AFTERNOON...
THIS WOULD YIELD HEAT INDICES GENERALLY IN THE UPPER 90S TO AROUND
100. THUS NO HEAT ADVISORY FOR TODAY. IF TEMPERATURES DID WARM A
FEW DEGREES ABOVE EXPECTED VALUES...COULD TAG ADVISORY CRITERIA IN
THE FAR SOUTH.
THERMAL PROFILES WARM A FEW DEGREES ON MONDAY WITH LOW TEMPS
TONIGHT PERHAPS A FEW DEGREES WARMER. WITH ENOUGH SUNSHINE THROUGH
EARLY AFTERNOON...HIGH TEMPERATURES SHOULD REACH LOWER 90S ALL
AREAS...PERHAPS A FEW LOCATIONS TAGGING MID 90S. SOUTHWESTERLY
WINDS NOW APPEARS STRONG ENOUGH TO PREVENT ANY LAKE COOLING...SO
HOT TEMPS ARE EXPECTED TO REACH THE BEACHES/LAKESHORE. DEWPOINTS
REMAIN IN THE LOWER/MID 70S. THIS COMBINATION PRODUCES HEAT
INDICES 100 NORTH TO 106 SOUTH...WHICH WOULD MEET ADVISORY
CRITERIA OVER AT LEAST THE SOUTHERN HALF OR THIRD OF THE CWA.
STILL 3RD PERIOD FROM THIS DISTANCE SO NOT PLANNING ANY HEADLINES
THIS MORNING BUT WILL HIGHLIGHT HEAT/HUMIDITY WITH AN SPS FOR THE
ENTIRE AREA.
A FRONTAL BOUNDARY WILL MOVE ACROSS THE MIDWEST TONIGHT AND MONDAY
AND SAG INTO THE IL/WI STATE LINE REGION MONDAY NIGHT. DISSIPATING
CONVECTION AHEAD OF THIS FRONT COULD POTENTIALLY SAG INTO THE FAR
NORTHERN CWA MONDAY MORNING WITH A LITTLE BETTER CHANCE OF
THUNDERSTORMS MONDAY AFTERNOON...MAINLY ACROSS THE NORTHERN CWA...
AS THE BOUNDARY SLOWLY DRIFTS SOUTH. CONFIDENCE ISN/T HIGH WITH
CONVECTIVE TRENDS DURING THIS TIME AND ITS POSSIBLE THAT THIS
ENTIRE PERIOD COULD REMAIN DRY. SHOULD THUNDERSTORMS BECOME MORE
WIDESPREAD AND/OR OCCUR SOONER...HIGH TEMPERATURES COULD BE TOO
WARM ON MONDAY...PARTICULARLY ACROSS THE NORTH.
THIS FRONTAL BOUNDARY THEN STALLS ACROSS OR NEAR THE AREA THROUGH
MID WEEK. DIFFICULT AT THIS POINT TO NARROW DOWN TIMING OR
LOCATION OF CONVECTION BEYOND MONDAY NIGHT AND THUS CHANCE POPS
FOR THE REMAINDER OF THE PERIOD WITH PERHAPS A SLIGHTLY BETTER
CHANCE FOR OVERNIGHT ACTIVITY TUESDAY NIGHT AND AGAIN WEDNESDAY
NIGHT. DESPITE LOW CONFIDENCE IN TIMING...WHEREVER THUNDERSTORMS
DO DEVELOP...THEY WILL BE EFFICIENT RAIN PRODUCERS AS DEWPOINTS IN
THE 70S ARE RAINED OUT. HEAVY RAIN AND LOCALIZED FLASH FLOODING
WILL BE POSSIBLE AT ANY TIME WITH ANY THUNDERSTORMS THROUGH THE
PERIOD. CMS
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 16Z...
* ADDITIONAL BRIEF MVFR CIG POSSIBLE AGAIN EARLY AFTERNOON.
* SOUTHEAST WINDS BECOMING EAST MID AFTERNOON. SPEEDS AROUND 10 KT.
* MVFR VSBY IN FOG POSSIBLE DAYBREAK MONDAY.
ED F
//DISCUSSION...UPDATED 12Z...
MVFR CIGS PERSIST THIS MORNING WITH MORE VARIABILITY ALONG THE
WESTERN FLANK OF THE CLOUD BAND FROM RFD TO JOT. EARLIER CIRRUS IS
ERODING ABOVE WHICH SHOULD ALLOW SUNSHINE TO HELP SCATTER THE
CLOUDS INTO THE MID MORNING HOURS. WITH HEATING AND START OF
MIXING NEW STRATOCU IS EXPECTED TO DEVELOP MID TO LATE MORNING.
THIS COULD BE OCCASIONALLY BROKEN IN COVERAGE BUT EXPECT SCATTERED
SKIES FOR THE BULK OF THE AFTERNOON. WILL NEED TO MONITOR A PATCH
OF IFR CIGS FROM NORTH OF VYS TO C75 TO PNT. THIS COULD BE A
CONCERN FOR RFD AS IT MAY SPREAD NORTHWARD TO SOME DEGREE.
SOUTHEAST WINDS WILL INCREASE TO AROUND 10 KT WITH SOME 10-12 KT
OBS ALREADY REPORTED THIS MORNING. A LAKE BREEZE IS EXPECTED TO
WORK INLAND AND TURN WINDS MORE EASTERLY AT ORD/MDW AND
NORTHEASTERLY AT GYY. EXPECT SPEEDS AROUND 10 KT WITH THE LAKE
BREEZE PASSAGE THOUGH THEY COULD BE A LITTLE BIT STRONGER FOR A
SHORT TIME. CANNOT RULE OUT A STRAY THUNDERSTORM THIS AFTERNOON AS
A WEAK UPPER DISTURBANCE CROSSES THE AREA MID/LATE AFTERNOON.
WINDS DO NOT LOOK TO COMPLETELY DROP OFF TONIGHT WHICH MAY HELP
LIMIT FOG/STRATUS DEVELOPMENT BUT MVFR VSBY DOES LOOK POSSIBLE.
WILL INCLUDE MENTION AT RFD/DPA WHICH ARE MORE PRONE TO VSBY
REDUCTION.
MDB
//ORD AND MDW CONFIDENCE...UPDATED 16Z...
* LOW TO MEDIUM CONFIDENCE IN ADDITIONAL BRIEF PERIOD OF MVFR CIGS EARLY
AFTERNOON.
* HIGH CONFIDENCE IN SOUTHEAST WINDS WITH MEDIUM CONFIDENCE IN SHIFT
TO EAST THIS AFTERNOON. MEDIUM-HIGH CONFIDENCE IN SPEEDS AROUND
10 KT.
* LOW TO MEDIUM CONFIDENCE IN MVFR VSBY IN FOG MONDAY MORNING.
ED F
//OUTLOOK FOR ORD/MDW FOR 00Z TUESDAY-12Z SUNDAY...UPDATED 12Z...
MONDAY NIGHT THROUGH SATURDAY...PERIODIC CHANCES FOR SHRA/TSRA AND
MVFR.
MDB
&&
.MARINE...
245 AM CDT
LOW PRESSURE CONTINUES TO MOVE NORTHWARD ACROSS THE DAKOTAS WHILE
HIGH PRESSURE OVER SOUTHEASTERN ONTARIO AND SOUTHERN QUEBEC MOVES
SOUTHWARD INTO NEW ENGLAND. A BETTER ORGANIZED PRESSURE GRADIENT
THAN WE HAVE OBSERVED THE PAST FEW DAYS IS IN PLACE ACROSS THE
AREA LEADING TO A BIT STEADIER SOUTHEAST TO EAST WIND ACROSS THE
LAKE TODAY WHICH WILL TURN SOUTHEAST THEN SOUTH TONIGHT AND MONDAY
MORNING. THE LOW WILL TURN EASTWARD ACROSS NORTHERN ONTARIO MONDAY
MORNING AND DRAG A COOL FRONTAL BOUNDARY SOUTHWARD. THE FRONT WILL
BE SLOW TO MOVE DOWN THE LAKE TUESDAY AND WEDNESDAY AND LOOKS TO
STALL OUT SOMEWHERE OVER OR JUST SOUTH OF THE LAKE GOING INTO
WEDNESDAY. AN UPPER TROUGH WILL BE MOVING ONSHORE OVER THE PACIFIC
NORTHWEST SUNDAY NIGHT AND DRIVE LOW PRESSURE DEVELOPMENT ACROSS
THE CENTRAL PLAINS. THIS LOW WILL TRACK NORTHEAST OVER OR NEAR THE
LAKE INTO FRIDAY WITH THE MAIN STORM TRACK SETTING UP ACROSS THE
LAKE THURSDAY AND FRIDAY. WIND SPEEDS FROM EARLY NEXT WEEK ONWARD
WILL BE TRICKY GIVEN THE PRESENCE OF THE FRONT BUT EXPECT
GENERALLY EAST TO NORTHEAST WINDS NORTH OF THE FRONT AND SOUTHERLY
TO THE SOUTH. THERE ARE STILL HINTS THAT COLDER AIR WILL SPILL IN
BEHIND THE FRONT BRINGING A PERIOD OF STRONGER WINDS MID TO LATE
WEEK.
MDB
&&
.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
1024 AM CDT Sun Aug 24 2014
.UPDATE...
ISSUED AT 1024 AM CDT SUN AUG 24 2014
15z/10am surface analysis shows a weak frontal boundary across
central Illinois, generally extending from near Galesburg to just
south of Lawrenceville. Despite presence of boundary, very little
in the way of cloud cover is noted on visible satellite. Most of
the clouds are further north and east across northern Illinois
arcing southeastward into Indiana. Models are showing a mostly dry
forecast today thanks to upper ridging that has sharpened over the
Midwest. NAM is completely dry, but both the HRRR and Rapid Refresh
hint at isolated convection this afternoon across south-central
Illinois. Do not see much support for this at the moment, but will
maintain just slight chance PoPs across the far southeast KILX
CWA. Main story today will be the hot and humid conditions. With
mostly sunny skies, afternoon high temperatures will reach the
lower 90s across the board, with heat index values exceeding 105
degrees along/south of a Lincoln to Marshall line.
&&
.SHORT TERM...(Today and tonight)
ISSUED AT 251 AM CDT SUN AUG 24 2014
The expected extended period of heat covering a total of four days
has prompted a move to upgrade the heat advisory to a heat warning
in our southern tier of counties. Even if some areas in the warning
do not hit 110F heat index any day, the extended period of
accumulative heat takes the toll as if you are hitting the higher
110F+ readings. Dewpoints climbed well above any guidance numbers
across our S-SE counties Saturday afternoon, with 80 and 81F
dewpoints reported. Guidance showed 75-76F Td for those same areas.
So heat index readings climbed over warning criteria of 110F even on
Saturday, when thoughts were that they would remain around 105F.
Slightly hotter conditions are expected for today and Monday, and if
dewpoints climb to where they were on Saturday, we should reach near
110F heat indices in our S-SE counties. Depending on how the thicker
cirrus clears today, highs should reach into the lower 90s in most
areas, with some mid 90s possible in the south-southwest where the
thermal ridge will begin to build into IL from the SW.
Thunderstorm chances will be more limited today than Saturday,
somewhat due to the increasing mid level temps which help to cap any
updrafts. Due to the orientation and position of the upper level
ridge and residual outflow boundary near our SE counties, we kept
afternoon 20 percent chance PoPs only SE of I-70 for this afternoon
and early evening. The ridge axis up the Mississippi River Valley
should guide that storm track to our N-NW. Very heavy rainfall and
gusty winds will be possible from any storm again today, due to very
high moisture content in the airmass and potential moisture loading
in any storms.
With clearing skies and light wind later tonight, fog will likely
develop into early Monday morning. The restriction to visibility
should not become dense, based on forecast soundings, but local
areas could drop below 1/2 mile near the Indiana border.
&&
.LONG TERM...(Monday through Saturday)
ISSUED AT 251 AM CDT SUN AUG 24 2014
Initial concern with this period continues to be with the heat.
Thermal ridge axis to extend over the CWA through Tuesday, with the
frontal boundary getting hung up to our north. This should result in
high temperatures of 91-95 over the entire forecast area Monday and
Tuesday. Will issue a heat advisory for Monday from around Peoria
southeast to Danville and Paris, as these areas should see heat
index values around 105, and will maintain the advisory around
Rushville and Havana. Will hold off on adding Tuesday at this point,
as there is some question about the amount of clouds and convection
potentially affecting this area.
Regarding that convection, am thinking that Monday and Monday night
should largely be dry, with MCS activity along the front to our
northwest. Most of the evening models show the MCS or its remnants
tracking southeast somewhat on Tuesday, and have PoP`s mentioned
roughly north of I-72. Additional MCS activity likely to form to our
north/northwest Tuesday night as well. The ECMWF/GEM start to sink
the frontal boundary down into our area by this point, while the GFS
has the warm front all the way into southern Wisconsin. Leaned
toward the former solutions and increase the PoP`s from northwest to
southeast Tuesday night into Wednesday.
The forecast beyond Wednesday remains a bit murky. The GFS is
slowing down a bit but remains much more progressive with a broad
trough moving eastward into the Mississippi Valley. The ECMWF and
GEM only slowly break down the ridge and pretty much don`t get the
wave even into the area until mid to late weekend. The tropical
system moving offshore of the East Coast doesn`t help matters
either. Have kept most of the PoP`s focused on the period through
Friday, but confidence in this part of the forecast is lower than
usual.
&&
.AVIATION...(For the 12Z TAFS through 12Z Monday morning)
ISSUED AT 657 AM CDT SUN AUG 24 2014
Minor MVFR fog will affect CMI through 14z, otherwise VFR
conditions are expected at the other terminal sites this morning.
Very hot high pressure will keep most cloud cover to a minimum
today, with some scattered 1500-2500FT clouds at times. No rain or
storms are expected near any TAF sites over the next 24 hours, as
mid-level warming advances into IL and pushes the storm tracks
north and east of our area. Forecast soundings show some light
MVFR fog may redevelop near CMI again later tonight, with lower
confidence any other sites will see fog.
Winds this morning will start out east-southeast, then veer to the
south this afternoon. Tonight they are expected to settle into a
southeast direction. Wind speeds should remain less than 10kt due
to a very weak pressure gradient.
&&
.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 from Noon to 7 PM CDT Monday FOR ILZ029-031-037-
038-043>046-055-057.
HEAT ADVISORY until 7 PM CDT Monday FOR ILZ036-040-041.
&&
$$
UPDATE...BARNES
SHORT TERM...SHIMON
LONG TERM...GEELHART
AVIATION...SHIMON
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
1253 AM CDT SUN AUG 24 2014
.DISCUSSION...
326 PM CDT
A PERSISTENT UPPER RIDGE THAT HAS BEEN SITTING OVER THE MIDWEST WILL
GRADUALLY FLATTEN AND BE PUSHED TO THE SOUTH AND EAST OVER THE NEXT
FEW DAYS...BUT NOT UNTIL THIS COMING THURSDAY OR FRIDAY WILL IT
AND ITS SURFACE MANIFESTATION BE PUSHED FAR ENOUGH AWAY TO ALLOW A
SURGE OF COOLER AND DRIER AIR INTO THE LOCAL AREA. UNTIL MIDWEEK
THE WARM AND HUMID AIRMASS WILL REMAIN IN PLACE...SUPPORTING
ONGOING CHANCES OF SHOWERS AND THUNDERSTORMS...WITH HEAT INDICIES
ON MONDAY APPROACHING THE LOCAL HEAT ADVISORY CRITERIA OF 105F.
POTENT SHORTWAVES LIFTING THROUGH THE TOP OF THE RIDGE TODAY HAVE
SUPPORTED A BROAD CLUSTER OF THUNDERSTORMS WITH HEAVY RAIN. MODELS
ARE IN REASONABLE AGREEMENT IN SHOWING SIMILAR BUT SOMEWHAT WEAKER
WAVES LIFTING THROUGH AGAIN TOMORROW...THOUGH THE FOCUS IS A BIT
FARTHER WEST. ALSO...MORE PRONOUNCED WARM ADVECTION AROUND THE
850MB LEVEL LOCALLY IS EXPECTED TO INHIBIT CONVECTIVE DEVELOPMENT
COMPARED TO WHAT WE SAW TODAY...AND THE INCREASED CLOUDINESS FROM
THE SHORTWAVES SHOULD ALSO SERVE TO LIMIT THE DEGREE OF AFTERNOON
SURFACE HEATING.
AS A WEAK SURFACE TROUGH APPROACHES SLOWLY FROM THE NORTHWEST...TSRA
CHANCES CREEP BACK UP AGAIN MONDAY AND TUESDAY ALONG WITH...AND
BECAUSE OF...MORE PRONOUNCED LOW LEVEL HEATING WITH SOUTH TO
SOUTHWEST WINDS SUPPORTING BETTER MIXING AND A WEAKER CAP ALOFT.
MONDAY LOOKS TO BE WARMER THAN EITHER SUNDAY OR TUESDAY...AND
AMPLE MOISTURE WILL SUPPORT HEAT INDICIES BETWEEN 100 AND
105...NEAR THE CRITERIA FOR A HEAT ADVISORY. IT IS A BIT EARLY TO
HOIST A HEADLINE BUT THIS WILL CONTINUE TO BE MONITORED.
BY WEDNESDAY THE TROUGH JUST TO OUR NORTHWEST WILL HAVE EVOLVED TO A
WARM FRONT ASSOCIATED WITH A LOW OVER THE PLAINS. THIS LOW THEN
LIFTS ALONG THIS BOUNDARY AND SETTLES OVER THE LOCAL AREA ON
THURSDAY BEFORE CONTINUING OFF TO THE EAST ON FRIDAY. HIGH
TEMPERATURES BOTH WEDNESDAY AND THURSDAY COULD BE TRICKY DEPENDING
ON WHERE THE SURFACE BOUNDARIES SET UP...BUT INCREASED CLOUDINESS
AND ONGOING TSRA CHANCES SHOULD KEEP THOSE DAYS COOLER THAN MONDAY
AND TUESDAY. THE MORE SIGNIFICANT CHANGE OF AIRMASS WILL THEN BE
IN PLACE ACROSS THE ENTIRE AREA BY FRIDAY AND SATURDAY...THOUGH
THE ECMWF IS A BIT SLOWER THAN THE GFS IN PUSHING THIS BOUNDARY
THROUGH.
LENNING
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 06Z...
* POTENTIAL FOR IFR CIGS/VSBY THROUGH DAYBREAK.
* EAST TO SOUTHEAST WINDS THROUGH EARLY AFTERNOON WITH A SHIFT T0
NORTHEAST POSSIBLE WITH PASSAGE OF LAKE BREEZE. SPEEDS MAY REACH
10 KT OR SO THIS AFTERNOON.
* LOW CHANCE FOR ISOLD TSRA OVERNIGHT AND AGAIN THIS AFTERNOON.
MDB
//DISCUSSION...UPDATED 06Z...
LOW PRESSURE OVER THE NORTHERN PLAINS EARLY THIS MORNING IS
CONTINUING TO LIFT NORTHWARD INTO CANADA WHILE HIGH PRESSURE
SETTLES SOUTHWARD INTO NEW ENGLAND. SURFACE WINDS HAVE DECOUPLED
IN THE LIGHT GRADIENT ALLOWING FOR LIGHT AND VARIABLE OR EVEN CALM
OBSERVATIONS. CIG/VSBY TRENDS WILL BE THE BIGGEST CHALLENGE THROUGH
DAYBREAK GIVEN THE LIGHT FLOW AND ABUNDANT MOISTURE. AN EXPANSIVE
CIRRUS SHIELD OVERHEAD MAY BE LIMITING FOG/STRATUS DEVELOPMENT AT
THE CURRENT TIME. EXPECT THAT THE TERMINALS WILL SEE SOME DEVELOP
BUT HAVE SLOWED THE ONSET BY A FEW HOURS AND MAINTAINED THE
SCATTERING/LIFTING DURING THE MID MORNING. WINDS WILL GENERALLY BE
SOUTHEASTERLY TODAY WITH SPEEDS COMING UP MODESTLY. A LAKE BREEZE
BOUNDARY IS EXPECTED TO DEVELOP AND MOVE INLAND THIS AFTERNOON SO
WILL CONTINUE WITH A SHIFT TO EAST WINDS AT ORD/MDW AND INDICATE A
NORTHEAST WIND AT GYY. SPEEDS MAY COME UP TO AROUND 10 KT BEFORE
DIMINISHING THIS EVENING. THUNDERSTORM CHANCES REMAIN FAIRLY LOW
WITH A CHANCE FOR A ROGUE CELL TONIGHT AND POSSIBLY A FEW CELLS
THIS AFTERNOON AS A MID/UPPER LEVEL TROUGH MOVES THROUGH.
MDB
//ORD AND MDW CONFIDENCE...UPDATED 06Z...
* LOW-MEDIUM CONFIDENCE IN CIGS/VSBY TIMING THIS MORNING.
* MEDIUM CONFIDENCE IN LAKE BREEZE REACHING ORD/MDW THIS
AFTERNOON. MEDIUM CONFIDENCE EASTERLY WINDS WILL INCREASE TO
AROUND 10 KT WITH PASSAGE.
* HIGH CONFIDENCE THAT TSRA POTENTIAL IS LOW.
MDB
//OUTLOOK FOR ORD/MDW FOR 12Z MONDAY-12Z SATURDAY...UPDATED 00Z...
MONDAY...CHANCE OF TSRA.
TUESDAY...CHANCE OF TSRA.
WEDNESDAY...CHANCE OF TSRA.
THURSDAY...CHANCE OF TSRA.
FRIDAY...CHANCE OF TSRA.
RODRIGUEZ
&&
.MARINE...
153 PM CDT
RELATIVELY LIGHT WINDS ARE IN PLACE THIS AFTERNOON AS A WEAK
PRESSURE GRADIENT IS IN PLACE ACROSS THE REGION. WINDS WILL BEGIN TO
FRESHEN UP SLIGHTLY TONIGHT AND VEER TO THE SOUTHEAST AS BROAD AREA
OF LOW PRESSURE OVER THE PLAINS BEGINS TO CONSOLIDATE AND DEEPEN AS
IT LIFTS TOWARDS THE CANADIAN PRAIRIES. THIS LOW WILL DRAG A WEAK
COLD FRONT SOUTH ACROSS LAKE MICHIGAN LATE TUESDAY INTO WEDNESDAY
WITH WINDS TURNING TO THE NORTH BEHIND THROUGH THE REMAINDER OF THE
WEEK.
BMD
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...NONE.
&&
$$
VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
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Area Forecast Discussion
NATIONAL WEATHER SERVICE LINCOLN IL
1106 PM CDT Sat Aug 23 2014
.UPDATE...
ISSUED AT 855 PM CDT SAT AUG 23 2014
Storms have finally pushed southeast of our area early this
evening as the outflow boundary from this morning`s convection
ignited scattered storms across the I70 corridor as it edged
southeast during the afternoon. The air mass from Springfield
south to I70 was characterized by surface base capes of 5500-6000
J/KG but very weak winds aloft, so storms developed quickly but
moved very slowly along the boundary. 00z ILX and DVN soundings
showing the stabilizing effect from the storms that moved across
the area this morning and early this afternoon with capes quite a
bit lower than analyzed across the south with a fairly significant
cap in place.
Looking at the latest HRRR model suggests very little threat for
rain overnight with the axis of the low level jet and 850 mb moisture
convergence further to our west across Iowa into northwest Illinois.
Will remove the slight chances over the east and southeast as the
rain has shifted out of our area. Will keep the threat for fog going
as it appears tonight will be a very similar setup to what occurred
over parts of central and east central Illinois last night. Very
light winds and copious amounts of moisture in the low levels should
lead to patchy fog development after midnight.
&&
.SHORT TERM...(This evening through Sunday)
ISSUED AT 319 PM CDT SAT AUG 23 2014
Southern flank of morning thunderstorm complex continues to impact
the northeast KILX CWA around Champaign and Danville this afternoon,
with only minimal development noted further southwest along the
trailing outflow boundary. Models have once again handled the
situation poorly, with the NAM/GFS being too aggressive with
convective development and the HRRR keeping system too far north.
Think storms will gradually push into Indiana over the next 3 to 4
hours, followed by only isolated convection across the eastern CWA
early this evening. Once daytime instability wanes, dry conditions
are expected overnight. With clearing skies and light winds, fog
will likely develop late tonight into Sunday morning. Forecast
soundings and numeric guidance both suggest at least some
restriction to visibilities, and based on what happened last night,
think its prudent to carry patchy fog late tonight. Upper ridge
axis will continue to control the weather across central Illinois on
Sunday, providing hot and mainly dry conditions. Some models are
hinting that widely scattered convection may fire along the Indiana
border by afternoon, but think this is a bit overdone. Will only
maintain slight chance PoPs across the far southeast, with dry
weather elsewhere. High temperatures will reach the lower 90s,
resulting in heat index values of 100 to 105 degrees.
&&
.LONG TERM...(Sunday night through Saturday)
ISSUED AT 319 PM CDT SAT AUG 23 2014
Medium range models are generally in good agreement for the first
few days of next week, then they digress pretty rapidly for two
reasons. First is the difference in solutions involving the speed
and strength of the upper level trough expected to move from the
Rockies to Midwest. This looks like it is being caused by the second
main difference, which is a lot of uncertainty with the speed and
motion of a pending tropical system in the western Atlantic. These
tropical systems tend to back up the west-east progression of
weather systems in the middle U.S. Thus, there is a greater than
normal level of uncertainty with the forecast for Wednesday through
the end of the week.
In the nearer term period for Monday and Tuesday, it appears likely
that the hot and humid conditions will continue. Monday could end up
being one of the hottest days with highs from 93-95 in central IL
and 91-93 in east/southeast IL. This will keep heat index values in
the 105-108 range in much of central and southeast IL, so will keep
the heat advisory going through Monday. Considered extending the
advisory into Tuesday, but will hold off for now since there is some
level of uncertainty as to the amount of increasing cloudiness
during the day, which could keep temps down just a bit.
The movement of a cold front, associated with aforementioned
approaching upper level trough, will really depend on the east coast
tropical system. The most likely scenario, which is not really
handled very well by any model, is that the front will slowly
approach - and may even get hung up in central IL for a day or two.
Thus, will stick with a prolonged period of scattered showers/t-storms
Wednesday into Friday. The cloudiness associated with this rain
potential will keep temperatures down in the 80s, ending the stretch
of hot weather. However, longer term trends indicate the possibility
that we may see a return to very warm conditions for Labor Day
weekend.
&&
.AVIATION...(For the 06Z TAFS through 06Z Sunday night)
ISSUED AT 1100 PM CDT SAT AUG 23 2014
Band of MVFR cigs (2000-3000 feet) extended from parts of central
thru west central Illinois and seems to be drifting slowly north
late this evening. Large MCS to our south will continue to drift
away from our area overnight with the main forecast concern being
extent of fog and low cigs acrs our area. Large area of thick cirrus
from the convection to our south and some of the lower clouds mentioned
above may influence how widespread the fog will get overnight.
Forecast soundings suggest the moisture in the 2000-3000 foot range
should become more scattered with time overnight with cirrostratus
clouds thinning later tonight so will continue from the previous
forecast in keeping the threat for at least MVFR if not IFR cigs/vsbys
in a few locations in the 09z-13z time frame.
What fog we do see late tonight should lift by 14 or 15z Sunday morning
with a mostly scattered cumulus deck developing by late morning or
early afternoon with soundings indicating cloud bases around 3000-3500
feet, which should dissipate quickly by evening. Surface winds will
be from an easterly direction overnight with speeds of 4 to 8 kts, and
then from a southeast to south direction on Sunday at 10 kts or less.
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
HEAT ADVISORY until 7 PM CDT Monday FOR ILZ042-047>054-056-
061>063-066>068-071>073.
HEAT ADVISORY from Noon Sunday to 7 PM CDT Monday FOR ILZ036-040-
041.
&&
$$
UPDATE...SMITH
SHORT TERM...BARNES
LONG TERM...MILLER
AVIATION...SMITH
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
238 AM CDT Sun Aug 24 2014
...Updated long term section...
.SHORT TERM...(Today and tonight)
ISSUED AT 201 AM CDT SUN AUG 24 2014
Models are in good agreement with moving a weak cold front across
west central and north central Kansas this morning. This surface
boundary will then become stationary across southwest and north
central Kansas by the early afternoon. A warm 850mb thermal ridge
axis was located ahead of this surface boundary at 00z Sunday and
both the NAM and GFS indicated a +1 to +2C 24 hour 850 temperature
change will occur from 00z Sunday to 00z Monday ahead of this
frontal boundary, mainly across south central Kansas. Northwest of
this frontal boundary the 850mb temperatures cool roughly 2 to 3C
from 00z Sunday to 00z Monday. Based on this expected trend and
where this surface boundary will be located late today will favor
highs at or a degree or two warmer than yesterday southeast of this
front. Highs today northwest of this front will be slightly cooler
and generally will be in the lower 90s.
Widely scattered thunderstorms will be possible late day/early
evening near and east of the surface boundary given improving
moisture and afternoon instability. After 00z Monday an upper
level jet will move out of the Rockies and across western Nebraska
which will place west central and north central Kansas near the
right entrance region of the upper level jet by 06z. As the upper
level dynamics improves across northern Kansas early tonight the
850mb winds from the NAM and GFS both suggested a +40kt low level
jet will be developing across western Kansas. Based on where the
nose of the low level jet will be located between 06z and 12z
Monday along with upslope flow across northeast Colorado/northwest
Kansas, location of the +12c to +14c 700mb temperature gradient,
and a 925mb to 850mb thta-e ridge axis across northern Kansas
overnight will continue to favor increasing chances of convection
across north central Kansas during the overnight period as evening
thunderstorms over south central Kansas tapers off.
.LONG TERM...(Monday through Saturday)
ISSUED AT 237 AM CDT SUN AUG 24 2014
Monday looks to be warm once again with temperatures reaching into
the mid to upper 90s with a few 100s across south central Kansas. A
few lingering showers will be possible across central and west
central Kansas in the morning with partly cloudy skies expected by
the afternoon. This will be short lived as an upper level shortwave
moves out from Colorado and into the Central High Plains Monday
night increasing cloudiness across the CWA. A chance of
thunderstorms will exist from late afternoon into the overnight
period, mainly across northern Kansas as well as central and west
central Kansas. Lows Monday and Tuesday mornings look to range from
the mid 60s across the KS/CO border to lower 70s across south
central Kansas. Meanwhile, an upper level low will be digging into
the Pacific northwest Monday before weakening into a opened
shortwave and ejecting eastward across the Rockies Tuesday then into
the Central Plains Wednesday into Thursday. Latest model runs have
this system moving slightly slower than previous as well as tracking
a little farther north. Nevertheless, thunderstorms look favorable
Tuesday afternoon through Thursday afternoon as this system
approaches and moves across Nebraska. The best chances of
precipitation will be across northern Kansas and the I-70 corridor
with lesser chances the farther south you go. A few lingering
showers may be possible across south central Kansas Thursday night,
otherwise expect decreasing cloudiness. Highs during this timeframe
look to decrease from the 90s Tuesday to 80s Wednesday through
Friday. Lows look to be in the 60s to lower 70s Wednesday morning
with 60s expected into this weekend. The remainder of the forecast
period looks dry as an upper level ridge builds across the western
United States. Skies will be mostly clear during this timeframe with
highs rebounding into the 90s by Saturday. Lows will remain in the
60s.
&&
.AVIATION...(For the 06Z TAFS through 06Z Sunday night)
ISSUED AT 1204 AM CDT SUN AUG 24 2014
A cold front will move into western and north central Kansas this
morning where it will become nearly stationary during the
afternoon hours. Based on 03z verification of this surface
boundary the NAM and HRRR had a decent handle with the movement of
this front so stay close to timing of frontal passage/wind shift
as it moves across the GCK and HYS areas late this morning. At
this time it appears this boundary will stay just west of DDC so
south/southwest winds at 10 to 15 knots will continue at DDC
through Sunday evening. BUFR soundings and HRRR indicating cloud
bases across western Kansas will be mainly at or above the 10000ft
AGL level tonight and Sunday so VFR conditions can be expected.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 98 69 98 71 / 10 20 20 30
GCK 94 67 97 70 / 10 10 30 40
EHA 94 66 96 68 / 10 10 20 20
LBL 97 67 97 70 / 10 10 20 20
HYS 95 67 97 70 / 10 20 30 40
P28 100 73 100 74 / 20 20 10 10
&&
.DDC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...Burgert
LONG TERM...Hovorka_42
AVIATION...Burgert
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
206 AM CDT Sun Aug 24 2014
...Updated short term discussion...
.SHORT TERM...(Today and tonight)
ISSUED AT 201 AM CDT SUN AUG 24 2014
Models are in good agreement with moving a weak cold front across
west central and north central Kansas this morning. This surface
boundary will then become stationary across southwest and north
central Kansas by the early afternoon. A warm 850mb thermal ridge
axis was located ahead of this surface boundary at 00z Sunday and
both the NAM and GFS indicated a +1 to +2C 24 hour 850 temperature
change will occur from 00z Sunday to 00z Monday ahead of this
frontal boundary, mainly across south central Kansas. Northwest of
this frontal boundary the 850mb temperatures cool roughly 2 to 3C
from 00z Sunday to 00z Monday. Based on this expected trend and
where this surface boundary will be located late today will favor
highs at or a degree or two warmer than yesterday southeast of this
front. Highs today northwest of this front will be slightly cooler
and generally will be in the lower 90s.
Widely scattered thunderstorms will be possible late day/early
evening near and east of the surface boundary given improving
moisture and afternoon instability. After 00z Monday an upper
level jet will move out of the Rockies and across western Nebraska
which will place west central and north central Kansas near the
right entrance region of the upper level jet by 06z. As the upper
level dynamics improves across northern Kansas early tonight the
850mb winds from the NAM and GFS both suggested a +40kt low level
jet will be developing across western Kansas. Based on where the
nose of the low level jet will be located between 06z and 12z
Monday along with upslope flow across northeast Colorado/northwest
Kansas, location of the +12c to +14c 700mb temperature gradient,
and a 925mb to 850mb thta-e ridge axis across northern Kansas
overnight will continue to favor increasing chances of convection
across north central Kansas during the overnight period as evening
thunderstorms over south central Kansas tapers off.
.LONG TERM...(Sunday night through Saturday)
ISSUED AT 254 PM CDT SAT AUG 23 2014
An upper level trough is forecast to move from the Western States on
Monday, then into the Intermountain West on Tuesday, then into the
Plains on Wednesday, with an associated cold front. The small
chances for thunderstorms will continue ahead of the cold front,
then increase with and just ahead of the front on Wednesday, with
lingering chances into Friday morning with the upper trough. The
upper trough then moves east of the Central Plains on Friday with
shortwave ridging and warming.
Daytime highs will be warm, ahead of the cold front, on Monday and
Tuesday in the mid to upper 90s, then cool into the 80s into Friday,
then back to around 90 by the Weekend. Overnight lows continue mild
around 70 on Sunday night into Tuesday night, then dip into the mid
60s into the Weekend.
&&
.AVIATION...(For the 06Z TAFS through 06Z Sunday night)
ISSUED AT 1204 AM CDT SUN AUG 24 2014
A cold front will move into western and north central Kansas this
morning where it will become nearly stationary during the
afternoon hours. Based on 03z verification of this surface
boundary the NAM and HRRR had a decent handle with the movement of
this front so stay close to timing of frontal passage/wind shift
as it moves across the GCK and HYS areas late this morning. At
this time it appears this boundary will stay just west of DDC so
south/southwest winds at 10 to 15 knots will continue at DDC
through Sunday evening. BUFR soundings and HRRR indicating cloud
bases across western Kansas will be mainly at or above the 10000ft
AGL level tonight and Sunday so VFR conditions can be expected.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 98 69 98 71 / 10 20 20 30
GCK 94 67 97 70 / 10 10 30 40
EHA 94 66 96 68 / 10 10 20 20
LBL 97 67 97 70 / 10 10 20 20
HYS 95 67 97 70 / 10 20 30 40
P28 100 73 100 74 / 20 20 10 10
&&
.DDC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...Burgert
LONG TERM...Kruse
AVIATION...Burgert
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
1207 AM CDT Sun Aug 24 2014
...Update synopsis and aviation discussion...
.SYNOPSIS...
ISSUED AT 1204 AM CDT SUN AUG 24 2014
At 00z Sunday a 500mb low was centered over western Wyoming and a
300mb +70 knot jet streak was located near the based of this upper
level system and stretched from northwest Colorado to southwest
Idaho. Further northwest a +90 knot 300mb jet extended from north
to south along the coast of British Columbia. A 700mb low was
located over eastern Montana with the 700mb trough extending south
of this low into eastern Colorado. East of this trough axis 700mb
temperatures at 00z Sunday ranged from 10c at North Platte to +12c
at Amarillo. Also east of the 700mb trough axis a wedge of higher
700mb dew points extended from the Texas panhandle into north
central Kansas. At the surface an area of low pressure was located
over southeast Colorado and a cold front extended northeast of
this surface low into southwest Nebraska. A warm 850mb thermal
ridge axis was located just ahead of this cold front. 850mb
temperatures at 00z Sunday along this ridge axis ranged from +23c
at Omaha to +27c at Dodge City to +28c at Amarillo.
&&
.SHORT TERM...(This evening through Sunday)
ISSUED AT 339 PM CDT SAT AUG 23 2014
A fairly strong shortwave trough by late August standards will progress
northeastward from the Intermountain west into North Dakota by Sunday
evening. A lee trough has developed ahead of this system; but low
level moisture over western Kansas was very limited. Also, upper
level temperatures were warm (-7C at 500mb and -32C at 300mb) so
that surface based CAPE was 1000 j/kg or less. A few showers had
developed in the Texas panhandle as of 20z along a convergence
line. This activity could build northeastward into south central
and southwest Kansas late this afternoon; but any shower or
thunderstorms would be isolated. With the loss of daytime heating,
precipitation is not expected after 8 to 9 pm since elevated
instability should be located along the edge of the mid level
capping inversion, well to the north in Nebraska. South winds will
keep temperatures from falling very fast through midnight. However,
wind speeds may drop to 5 to 10 kts by 12z as a surface trough
approaches from the west, and this may allow temperatures to fall
into the 60s to near 70F from Dodge City westward, with mid 60s
near the Colorado state line.
A trailing cold front associated with the aforementioned shortwave
trough will stall out over southwestern Kansas by Sunday afternoon.
A few thunderstorms may develop again, mainly for areas south and
east of Dodge City. Surface dewpoints will be a little higher
(around 60F) so that surface based CAPE will be around 1500 j/kg.
Vertical wind shear will be weak so that severe weather is not
expected.
.LONG TERM...(Sunday night through Saturday)
ISSUED AT 254 PM CDT SAT AUG 23 2014
An upper level trough is forecast to move from the Western States on
Monday, then into the Intermountain West on Tuesday, then into the
Plains on Wednesday, with an associated cold front. The small
chances for thunderstorms will continue ahead of the cold front,
then increase with and just ahead of the front on Wednesday, with
lingering chances into Friday morning with the upper trough. The
upper trough then moves east of the Central Plains on Friday with
shortwave ridging and warming.
Daytime highs will be warm, ahead of the cold front, on Monday and
Tuesday in the mid to upper 90s, then cool into the 80s into Friday,
then back to around 90 by the Weekend. Overnight lows continue mild
around 70 on Sunday night into Tuesday night, then dip into the mid
60s into the Weekend.
&&
.AVIATION...(For the 06Z TAFS through 06Z Sunday night)
ISSUED AT 1204 AM CDT SUN AUG 24 2014
A cold front will move into western and north central Kansas this
morning where it will become nearly stationary during the
afternoon hours. Based on 03z verification of this surface
boundary the NAM and HRRR had a decent handle with the movement of
this front so stay close to timing of frontal passage/wind shift
as it moves across the GCK and HYS areas late this morning. At
this time it appears this boundary will stay just west of DDC so
south/southwest winds at 10 to 15 knots will continue at DDC
through Sunday evening. BUFR soundings and HRRR indicating cloud
bases across western Kansas will be mainly at or above the 10000ft
AGL level tonight and Sunday so VFR conditions can be expected.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 69 98 71 96 / 20 20 20 30
GCK 67 96 70 95 / 10 20 20 30
EHA 66 95 68 93 / 10 20 20 30
LBL 67 96 70 95 / 20 20 20 30
HYS 67 96 71 95 / 20 30 30 30
P28 73 98 75 99 / 20 10 10 10
&&
.DDC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...Burgert
SHORT TERM...Finch
LONG TERM...Kruse
AVIATION...Burgert
AREA FORECAST DISCUSSION
NWS PADUCAH KY
626 AM CDT Sun Aug 24 2014
.Update...
Updated aviation section for 12z taf issuance
&&
.SHORT TERM...
Issued at 333 AM CDT Sun Aug 24 2014
There is very little change in the synoptic pattern or the
forecast this forecast cycle. The main issues continue to be the
timing and location of convection...as well as their impacts on
temps/dew points/heat indices.
In the near term...an outflow boundary from last evenings mcs
over the Lower Ohio Valley made it as far southwest as the
Missouri Bootheel by 08z. This mcs and its outflow has stabilized
the air mass for the time being...especially east of the
Mississippi River.
The latest model data /especially the rap/ still indicates the
surface wind flow will become easterly during the day today. The
rap indicates a surface convergence zone along the leading edge of
this easterly push. The RAP model pools moisture along this
boundary...which results in high dew points and an axis of strong
instability by this afternoon. This axis extends from southern
Illinois into western Kentucky by early this afternoon. Based on
this data...will expand slight chance pops as far west as the
Mississippi River counties again today. The coverage of convection
should be rather isolated...given drier mid level air
overspreading the Mississippi Valley on water vapor imagery.
Heat indices will again reach 105 in most areas today. Even where
clouds were widespread on Saturday...heat indices still exceeded
105 due to extremely high dew points around 80. High temps should
be very similar to those on Saturday...except where localized
convection occurs.
The daily potential for isolated convection should be suppressed
further to the south and east Monday and Tuesday as the mid level
ridge axis establishes itself along the Ohio Valley. Will keep
slight chance pops mainly southeast of the Ohio River both days.
As for temps...will generally follow the hotter gfs mos for both
Monday and Tuesday. Some of the model guidance continues to lower
temps slightly. Given that the deep layer ridge will be positioned
nearly overhead through the period...this cooling looks suspect.
There may be a slight lowering of dew points as the low level flow
remains out of the east. This may lower heat indices a few
degrees...but they are still forecast to reach 100 to 105 Tuesday.
.LONG TERM...
Issued at 333 AM CDT Sun Aug 24 2014
Well there continues to be a rift between the GFS and ECMWF/GEM in
their 00Z runs. The trend with all of the models is slower with the
eastward movement of the western U.S. low/trough. The 00Z ECMWF is
leading the charge and tonight`s run basically builds an upper
ridge north of the trough, effectively removing it from the
westerlies. Am beginning to wonder if this system and its associated
surface boundary are ever going to reach our region.
The 00Z GFS brings the upper trough and cold front through the area
Thursday and Thursday night, and then brings drier, cooler air into
the region for Friday and next Saturday. The Canadian/GEM is a lot
closer to the ECMWF solution, but not quite as slow. Really think
the ECMWF is onto something, so will lean toward it for this
forecast.
The problem with the ECMWF and GEM solutions with respect to our
existing forecast is that they allow a significant upper trough to
dive southeast into New England by Thursday morning. That brings a
backdoor cold front southward into our northern counties late
Wednesday and Wednesday night. The front ends up draped across the
area from northwest to southeast Thursday and Friday. This leads to
a decent chance of convection both days.
The other effect of the ECMWF solution is the potential for the heat
and humidity to linger through much of the work week, if not all the
way through next Saturday. Bumped up temperatures just a bit
throughout the extended. Heat indices on Wednesday are generally at
or below 100, so there will be no need to extend the Heat Advisory
any further with this forecast package.
&&
.AVIATION...
Issued at 626 AM CDT Sun Aug 24 2014
Some patchy fog and local areas of low stratus developed before
sunrise in the Wabash Valley and western KY. Most of this fog and
stratus has not reached the taf sites as of 11z. It is expected to
burn off before having a chance to impact the taf sites. There will
likely be more fog and stratus early Monday morning...but it is once
again not expected to be widespread.
Some thunderstorms may develop again today into this evening. The
best chance at this time appears to be in the kpah/kcgi
areas...where the atmosphere was not stabilized too much by
thunderstorms last night. Will handle with vcts for those sites.
Otherwise...scattered to broken cumulus will develop at all sites by
noon. Bases should be around 3 to 4k feet.
&&
.PAH WATCHES/WARNINGS/ADVISORIES...
KY...HEAT ADVISORY until 7 PM CDT Tuesday FOR KYZ001>022.
MO...HEAT ADVISORY until 7 PM CDT Tuesday FOR MOZ076-086-087-100-
107>112-114.
IL...HEAT ADVISORY until 7 PM CDT Tuesday FOR ILZ075>078-080>094.
IN...HEAT ADVISORY until 7 PM CDT Tuesday FOR INZ081-082-085>088.
&&
$$
SHORT TERM...MY
LONG TERM....DRS
AVIATION...MY
AREA FORECAST DISCUSSION
NWS PADUCAH KY
333 AM CDT Sun Aug 24 2014
.SHORT TERM...
Issued at 333 AM CDT Sun Aug 24 2014
There is very little change in the synoptic pattern or the
forecast this forecast cycle. The main issues continue to be the
timing and location of convection...as well as their impacts on
temps/dew points/heat indices.
In the near term...an outflow boundary from last evenings mcs
over the Lower Ohio Valley made it as far southwest as the
Missouri Bootheel by 08z. This mcs and its outflow has stabilized
the air mass for the time being...especially east of the
Mississippi River.
The latest model data /especially the rap/ still indicates the
surface wind flow will become easterly during the day today. The
rap indicates a surface convergence zone along the leading edge of
this easterly push. The RAP model pools moisture along this
boundary...which results in high dew points and an axis of strong
instability by this afternoon. This axis extends from southern
Illinois into western Kentucky by early this afternoon. Based on
this data...will expand slight chance pops as far west as the
Mississippi River counties again today. The coverage of convection
should be rather isolated...given drier mid level air
overspreading the Mississippi Valley on water vapor imagery.
Heat indices will again reach 105 in most areas today. Even where
clouds were widespread on Saturday...heat indices still exceeded
105 due to extremely high dew points around 80. High temps should
be very similar to those on Saturday...except where localized
convection occurs.
The daily potential for isolated convection should be suppressed
further to the south and east Monday and Tuesday as the mid level
ridge axis establishes itself along the Ohio Valley. Will keep
slight chance pops mainly southeast of the Ohio River both days.
As for temps...will generally follow the hotter gfs mos for both
Monday and Tuesday. Some of the model guidance continues to lower
temps slightly. Given that the deep layer ridge will be positioned
nearly overhead through the period...this cooling looks suspect.
There may be a slight lowering of dew points as the low level flow
remains out of the east. This may lower heat indices a few
degrees...but they are still forecast to reach 100 to 105 Tuesday.
.LONG TERM...
Issued at 333 AM CDT Sun Aug 24 2014
Well there continues to be a rift between the GFS and ECMWF/GEM in
their 00Z runs. The trend with all of the models is slower with the
eastward movement of the western U.S. low/trough. The 00Z ECMWF is
leading the charge and tonight`s run basically builds an upper
ridge north of the trough, effectively removing it from the
westerlies. Am beginning to wonder if this system and its associated
surface boundary are ever going to reach our region.
The 00Z GFS brings the upper trough and cold front through the area
Thursday and Thursday night, and then brings drier, cooler air into
the region for Friday and next Saturday. The Canadian/GEM is a lot
closer to the ECMWF solution, but not quite as slow. Really think
the ECMWF is onto something, so will lean toward it for this
forecast.
The problem with the ECMWF and GEM solutions with respect to our
existing forecast is that they allow a significant upper trough to
dive southeast into New England by Thursday morning. That brings a
backdoor cold front southward into our northern counties late
Wednesday and Wednesday night. The front ends up draped across the
area from northwest to southeast Thursday and Friday. This leads to
a decent chance of convection both days.
The other effect of the ECMWF solution is the potential for the heat
and humidity to linger through much of the work week, if not all the
way through next Saturday. Bumped up temperatures just a bit
throughout the extended. Heat indices on Wednesday are generally at
or below 100, so there will be no need to extend the Heat Advisory
any further with this forecast package.
&&
.AVIATION...
Issued at 1130 PM CDT SAT AUG 23 2014
Convection induced by a westward moving outflow boundary at KPAH
should end by the time the 06Z TAFS begin so will have no mention
of any tsra. If we can get the clouds to clear out and the winds
to become calm for a while, we might actually get some fog to
develop. Opted to just leave the MVFR vsbys going for now since
confidence is still low whether or not it will form. Otherwise,
the rest of the overnight and into Sunday morning should be
tranquil. Plenty of instability will be present during the day on
Sunday for more isolated to scattered storms. But coverage of
storms is still unknown attm so will opt to leave any mention out
at this time. Winds will remain light and variable.
&&
.PAH WATCHES/WARNINGS/ADVISORIES...
KY...HEAT ADVISORY until 7 PM CDT Tuesday FOR KYZ001>022.
MO...HEAT ADVISORY until 7 PM CDT Tuesday FOR MOZ076-086-087-100-
107>112-114.
IL...HEAT ADVISORY until 7 PM CDT Tuesday FOR ILZ075>078-080>094.
IN...HEAT ADVISORY until 7 PM CDT Tuesday FOR INZ081-082-085>088.
&&
$$
SHORT TERM...MY
LONG TERM....DRS
AVIATION...CW
AREA FORECAST DISCUSSION
NWS JACKSON KY
222 AM EDT SUN AUG 24 2014
.UPDATE...
ISSUED AT 1051 PM EDT SAT AUG 23 2014
SENT OUT ONE LAST UPDATE TO THE FORECAST FOR THIS SHIFT. SHOWERS AND
STORMS OVER THE PAST HOUR OR SO HAVE MADE THEIR WAY INTO PORTIONS OF
PULASKI...WAYNE...AND MCCREARY COUNTIES...SO PRECIPITATION
PROBABILITIES AND QPF AMOUNTS DOWN THERE WERE BEEFED UP THROUGH 4 OR
5Z TONIGHT. WITH ISOLATED STORMS PUSHING SOUTHWARD TOWARD PIKE
COUNTY AND WITH OTHER ISOLATED STUFF HAVING POPPED UP AND DIED IN OUR
BLUEGRASS COUNTIES...DECIDED TO GO AHEAD AND LEAVE IN A SLIGHT CHANCE
OF SHOWERS AND STORMS FOR THE MAJORITY OF THE AREA THROUGH 12Z. THE
EXCEPTION WILL BE WAYNE COUNTY WHERE LIKELY POPS WERE INTRODUCED TO
ACCOUNT FOR THE ENHANCED SHOWER AND STORM ACTIVITY DOWN WHICH APPEARS
IS BEING DRIVEN BY OUTFLOW BOUNDARIES FROM THE STORMS ONGOING IN EAST
CENTRAL KENTUCKY. FOR FORMATION WILL STILL BE OF CONCERN TOO THROUGH
THE OVERNIGHT SO IT WAS AGAIN FEATURED IN THE FORECAST THROUGH 13Z
TOMORROW WITH LOCALLY DENSE FOG POSSIBLE IN OUR VALLEYS.
UPDATE ISSUED AT 733 PM EDT SAT AUG 23 2014
WILL BE SENDING OUT AND UPDATED ZONE FORECAST SHORTLY TO REMOVE THE
PRE FIRST PERIOD PUT IN BY THE DAY SHIFT AND TO DECREASE PRECIPITATION
CHANCES CROSS THE ENTIRE AREA FOR THE REMAINDER OF THE OVERNIGHT
PERIOD INTO EARLY TOMORROW MORNING. THE LATEST NAM12 AND HRRR MODEL
RUNS MATCH UP WELL WITH THE ISOLATED SHOWER AND STORM COVERAGE
CURRENTLY BEING OBSERVED ACROSS EASTERN KENTUCKY. BASED ON THE THE
FACT THAT MOST OF THE LONG LIVED SHOWERS AND STORMS ARE CONFINED TO
CENTRAL KENTUCKY AND WITH THEIR SLOW SOUTHWARD DIRECTION OF
MOVEMENT...AND WITH THE SUN DUE TO SET SOON...IT SIMPLY DOES NOT
APPEAR THAT WE WILL SEE MORE THAN ISOLATED SHOWERS OR STORMS ACROSS
THE MAJORITY OF THE AREA TONIGHT. THERE STILL IS A SMALL CHANCE OF
SCATTERED ACTIVITY WEST OF I75...BUT EVEN THAT IS IN QUESTION AT THIS
POINT. THE FOG FORMATION OVERNIGHT IS ON TRACK...HOWEVER...WITH CLEAR
SKIES...LIGHT WINDS...AND AMPLE SURFACE MOISTURE IN PLACE. WE WILL
STILL LIKELY SEE AREAS OF DENSE FOG LATE TONIGHT INTO EARLY TOMORROW
MORNING...WITH THE MOST FAVORED AREAS BEING OUR VALLEYS. THE NEW
FORECAST WILL REFLECT MUCH LOWER PRECIPITATION CHANCES OVERNIGHT AND
WIDESPREAD FOG.
&&
.SHORT TERM...(THIS EVENING THROUGH SUNDAY NIGHT)
ISSUED AT 350 PM EDT SAT AUG 23 2014
19Z SFC ANALYSIS SHOWS OUR CONTINUING WEATHER CHALLENGE WITH THE LOW
PRESSURE OUT TO THE WEST AND HIGH PRESSURE TO THE SOUTH. A WAVY
NORTHWEST TO SOUTHEAST FRONT EXISTS JUST NORTH OF OUR AREA.
MEANWHILE...ALOFT...A RIDGE IS FOUND THROUGH THE LOWER MIDSECTION OF
THE NATION WITH A DIGGING TROUGH MOVING INTO THE MID ATLANTIC STATES.
THIS PLACES CENTRAL AND EASTERN KENTUCKY IN THE TRACK OF ENERGY
MOVING FROM THE UPPER MIDWEST INTO THE SOUTHERN APPALACHIANS TODAY.
THESE FEATURES HAVE BEEN COMBINING LATELY TO PRODUCE CLUSTERS OF
SHOWERS AND THUNDERSTORMS GENERALLY STARTING IN THE LATE AFTERNOON
AND LASTING INTO THE EVENING. THE HIGH PW AIR IN PLACE OVER THE
AREA...ALONG WITH THE DEWPOINTS PUSHING THE MID 70S...MAKES FOR
PROLIFIC RAIN PRODUCING CELLS. AS HAS BEEN THE CASE REMAINS SO
HEADING INTO LATE AFTERNOON...THOUGH THE AXIS OF CONCERN HAS SHIFTED
SLIGHTLY WEST OWING TO THE WIGGLE OF THE RIDGE IN RESPONSE TO THE
DIGGING TROUGH. CURRENTLY SCATTERED AND ISOLATED SHOWERS/STORMS ARE
DOTTING THE CUMBERLAND VALLEY WITH SIGNS OF LARGER CLUSTERS STARTING
TO TAKE SHAPE TO THE NORTHWEST. THOUGH DELAYED A BIT BY THE LOW
STRATUS DECK FOLLOWING THE DENSE FOG THIS MORNING...TEMPERATURES HAVE
CLIMBED SMARTLY INTO THE MIDDLE AND UPPER 80S THROUGH THE AREA AND
WITH SUCH HIGH DEWPOINTS ARE YIELDING HEAT INDICES IN THE 95 TO 100
DEGREE RANGE. WINDS HAVE BEEN MAINLY LIGHT AND VARIABLE THROUGH THE
AREA.
THE MODELS ARE ALL IN PRETTY GOOD AGREEMENT ALOFT WITH THE WIGGLE
WEST AND THEN BACK EAST OF THE UPPER RIDGE INTO MONDAY MORNING.
SHORTWAVE ENERGY MOVING SOUTH BETWEEN THE UPPER SYSTEMS WILL PASS
THROUGH CENTRAL AND EASTERN KENTUCKY TONIGHT WITH ONLY WEAKER PACKETS
FORESEEN THROUGH THE REST OF THE WEEKEND. GIVEN THE AGREEMENT OF THE
MODELS AND THE SMALLER SCALE NATURE OF CONVECTIVE ACTIVITY OF THIS
REGIME HAVE AGAIN FAVORED THE HRRR AND NAM12 THROUGH THE FIRST 18 TO
36 HOURS AND A MODEL CONSENSUS AFTER THAT INTO MONDAY MORNING.
SENSIBLE WEATHER WILL FEATURE ISOLATED AND SCATTERED CONVECTION
AROUND EAST KENTUCKY THROUGH THE NEXT SEVERAL HOURS WITH AN
DECENT POTENTIAL EVOLUTION OF STORMS INTO A LARGER SYSTEM LATER IN
THE FIRST PART OF THE EVENING SOMEWHERE TO THE NORTHWEST. THE
INGREDIENTS ARE THERE FOR ANOTHER ROUND OF SUCH STORMS AND THE
EXCESSIVE RAINFALL THEY PRODUCE. STILL THE BEST INDICATIONS ARE THAT
THE WORST OF ANY SUCH DEVELOPMENT WILL JUST BRUSH OUR SOUTHWESTERN
COUNTIES WHERE WE ARE NOT QUITE AS SATURATED AS THE EAST. THIS IS
GOOD NEWS...BUT GIVEN THE LOW FFG IN THE EAST JUST ABOUT ANY HEALTHY
STORM THERE WILL PROMPT FLASH FLOODING CONCERNS. WITH THE STILL HIGH
PWS AND INSTABILITY ACROSS THE ENTIRE AREA CANNOT CALL ANY PLACE FREE
OF LOCALIZED FLASH FLOOD CONCERNS. THE ACTIVITY IS EXPECTED TO DIE
DOWN LATER THIS EVENING AND WHEN COMBINED WITH AT LEAST PARTIAL
CLEARING WILL LIKELY BRING ABOUT ANOTHER BLANKET OF FOG BECOMING
DENSE IN AREAS TOWARD DAWN. WILL HIT THIS...IN ADDITION TO THE
STORM/FLOOD CONCERNS...HARD IN THE HWO. ONCE THE FOG BURNS OFF ON
SUNDAY...PARTLY SUNNY SKIES WILL AGAIN BUILD THE HEAT AND INSTABILITY
THROUGH THE AREA WHILE LOWER PWS FOR MUCH OF THE AREA WILL LIMIT TO A
SMALLER EXTENT FLASH FLOOD CONCERNS. EXPECT SOME COOLER AND...MORE
IMPORTANTLY...DRIER AIR TO MAKE IT INTO THE EAST BY EVENING AS A BACK
DOOR COLD FRONT PUSHES WEST THROUGH THE AREA ALLOWING SOME LOWS
CLOSER TO NORMAL FOR THIS TIME OF YEAR IN THE FAR EAST BY DAWN
MONDAY. AGAIN PATCHY FOG WILL BE A CONCERN DEPENDING ON THE RAINS
OF THE PREVIOUS DAY AND CLEARING THAT NIGHT.
STUCK WITH THE CONSSHORT AS A STARTING POINT FOR THE T/TD/WINDS
THROUGH THE FIRST 24 HOURS AND THE SUPERBLEND THEREAFTER. MADE SOME
MINOR ADJUSTMENTS BASED ON TERRAIN FOR LOWS TONIGHT AND SUNDAY
NIGHT. AS FOR POPS...ENDED UP CLOSER TO THE WETTER MET GUIDANCE
TONIGHT AND THEN NEARER THE MAV NUMBERS FOR THE REST OF THE SHORT
TERM PORTION OF THE FORECAST.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 239 PM EDT SAT AUG 23 2014
STRONG RIDGING WILL DOMINATE THE EASTERN CONUS THROUGH NEXT WEEK
WITH SUMMER-LIKE WEATHER CONTINUING. FORTUNATELY...WITH A STRONGER
CAP PRESENT...CONVECTION WILL BE HELD MORE AT BAY. CANNOT RULE OUT A
STRAY AFTERNOON SHOWER OR STORM EACH DAY...BUT SHOULD BE NOTHING
LIKE WE HAVE SEEN LATELY. PLANNING TO GO WITH A DIURNAL TREND WITH
POPS THROUGH THE END OF THE PERIOD WITH POPS PEAKING EACH AFTERNOON
WITH MAXIMUM HEATING/INSTABILITY. A SURFACE TROUGH MAY APPROACH FROM
THE WEST EARLY NEXT WEEKEND...BUT A TROPICAL SYSTEM DEVELOPING OVER
THE ATLANTIC BASIN...MAY HAVE A TENDENCY TO SLOW DOWN THE
ADVANCEMENT OF THIS FEATURE UNTIL SOMETIME LATE IN THE WEEKEND OR
THE FOLLOWING WEEK.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT)
ISSUED AT 222 AM EDT SUN AUG 24 2014
THE MAIN CONCERN DURING THIS TAF PERIOD CONTINUES TO BE THE OVERNIGHT
FOG DEVELOPMENT...OR POSSIBLE LACK THEREOF. A WEAK LOW LEVEL
CIRCULATION...A WEAK BOUNDARY TO OUR WEST...AND GOOD MOISTURE
AVAILABILITY HAS LED TO SHOWERS ACROSS MUCH OF CENTRAL KY...AND A
HIGH CLOUD DECK CONSUMING MUCH OF KY. THE SHOWERS ARE MAINLY
AFFECTING THE FAR SW COUNTIES IN THE CWA...INCLUDING KSME...AND ARE
SHOWING SIGNS OF WEAKENING. EXPECT FEW IMPACTS FROM THESE SHOWERS AT
KSME OTHER THAN A LOW CLOUD DECK FOR THE NEXT FEW HOURS.
OTHERWISE...THE INFLUX OF CLOUDS HAS SO FAR HAMPERED FOG DEVELOPMENT
AT ALL OTHER TAF SITES EXCEPT FOR KSJS WHERE FOG HAD DEVELOPED
BEFORE THE CLOUDS MOVED IN THIS EVENING. FOG WILL CONTINUE TO FLUCTUATE
IN AND OUT OF AIRPORT MINS AT KSJS THROUGHOUT THE NIGHT...BUT SHOULD
ULTIMATELY REMAIN IN PLACE THROUGH DAYBREAK. ELSEWHERE...EXPECT FOG
TO STAY IN THE VALLEYS OVERNIGHT...THEN LIFT IN THE EARLY MORNING
HOURS AND AFFECT TAF SITES BEFORE BURNING OFF SHORTLY AFTER BETWEEN 8
AND 10AM. SUNSHINE AND SCT DIURNALLY DRIVEN MID LEVEL CLOUDS ARE
EXPECTED DURING THE DAY TOMORROW. THERE IS THE POTENTIAL FOR
SCATTERED AFTERNOON CONVECTION AS WELL...BUT UNTIL STORMS
DEVELOP...CONFIDENCE FOR IF AND WHEN THE STORMS WOULD AFFECT THE TAF
SITES IS TOO LOW TO WARRANT MENTION IN TAFS AT THIS TIME.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...AR
SHORT TERM...GREIF
LONG TERM...KAS
AVIATION...JMW
AREA FORECAST DISCUSSION
NWS CARIBOU ME
603 AM EDT SUN AUG 24 2014
.SYNOPSIS...
HIGH PRESSURE WILL SLIDE SOUTH OF THE AREA AND REMAIN OVER
SOUTHERN NEW ENGLAND THROUGH TUESDAY. A COLD FRONT WILL MOVE
THROUGH ON WEDNESDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
555 AM UPDATE...
UPDATED TO INCREASE SKY COVER FOR THIS MORNING INTO EARLY
AFTERNOON. ALSO, GOT RID OF FOG IN NORTHERN MAINE WHERE THE MID
LEVEL CLOUD DECK EXISTS. AT 6 AM, MID LEVEL CLOUD DECK EXISTS FROM
HOULTON NORTH, AND IS MOVING SOUTHWEST. NO MODELS HAD A HANDLE ON
THIS CLOUD DECK EARLIER TONIGHT. RAP AND NAM NOW HAVE A REASONABLE
HANDLE ON THE CLOUD DECK AND USED A BLEND OF THEM FOR THE DAY,
WHICH MAKES FOR MOSTLY CLOUDY SKIES THIS MORNING FROM ROUGHLY
MILLINOCKET NORTHEAST. SKIES WILL BECOME PARTLY CLOUDY LATER THIS
AFTERNOON OVER THE NORTH. THE INCREASED CLOUDS MAY KEEP TEMPS DOWN A
BIT, BUT OPTED TO LEAVE THEM AS IS FOR NOW.
PREVIOUS DISCUSSION...
ANOTHER QUIET DAY TODAY WITH JUST ISOLATED AFTERNOON SHOWERS
MAINLY FROM THE CENTRAL HIGHLANDS EAST TO AROOSTOOK COUNTY WHERE
THERE IS THE BEST LOW LEVEL CONVERGENCE. THERE IS ACTUALLY A FAIR
AMOUNT OF CAPE TO WORK WITH, BUT WITH THE UPPER RIDGE ALOFT AND
STRONG INVERSION AROUND 700 MB, IT`S GOING TO BE TOUGH TO REALIZE
MUCH CONVECTION. FELT ISOLATED SHOWERS WAS THE BEST COMPROMISE
APPROACH.
TEMPERATURES WILL CONTINUE TO BE WARMER THAN THE PREVIOUS DAY,
WITH HIGHS MAINLY IN THE LOWER 80S. WITH THE FAIRLY LIGHT PRESSURE
GRADIENT AND SUBSTANTIAL HEATING OF THE LAND, EXPECT A DECENT SEA
BREEZE, WHICH IS RESOLVED IN THE WIND GRIDS AND TEMPERATURE CURVE
WITH TEMPS FALLING LATE AFTERNOON NEAR THE COAST.
QUIET NIGHT TONIGHT WITH MOSTLY CLEAR SKIES AND MILD TEMPERATURES.
DO NOT EXPECT MUCH RADIATION FOG, AS THERE APPEARS TO BE A BIT
MORE LOW LEVEL WIND THAN PREVIOUS NIGHTS WHICH COULD KEEP FOG AWAY.
&&
.SHORT TERM /MONDAY THROUGH WEDNESDAY/...
MONDAY WILL BE SUNNY AND VERY WARM WITH HIGHS IN THE MID TO UPPER
80S FOR MOST LOCATIONS. A STRONG UPPER LEVEL RIDGE WILL DOMINATE
AREA WEATHER INTO TUESDAY NIGHT. LOWS MONDAY NIGHT WILL ONLY DROP
TO AROUND 60F AND TEMPERATURES ON TUESDAY WILL SHOOT UP TO THE
UPPER 80S WITH AN UPTICK IN HUMIDITY. A COLD FRONT WILL EASE
SOUTHWARD THROUGH QUEBEC TUESDAY NIGHT AND PROVIDE THE CHANCE OF A
THUNDERSTORM TOWARDS THE ST JOHN VALLEY LATER TUESDAY NIGHT WITH
ELEVATED INSTABILITY THROUGH THE NIGHT. LOWS WILL ONLY BE IN THE
LOW TO MID 60S.
&&
.LONG TERM /WEDNESDAY NIGHT THROUGH SATURDAY/...
WEDNESDAY WILL THE DAY THAT THE COLD FRONT CROSSES THE FORECAST
AREA FROM NORTH TO SOUTH. THE TIMING OF ITS CROSSING PRESENTS THE
BEST OPPORTUNITY FOR STRONG STORMS SOUTH OF HOULTON. THE SOUTHERN
HALF OF THE FORECAST AREA WILL HAVE THE GREATEST SURFACE-BASED
CAPE WITH HIGHS APPROACHING 90F. DEWPOINTS RISING TO THE MID 60S
AHEAD OF THE FRONT IN THE SOUTHERN HALF OF THE FORECAST AREA WILL
ADD MORE FUEL. THUNDERSTORMS THAT DEVELOP COULD REACH 35K TO 40K
FT IF THEY CAN OVERCOME THE CAP NEAR H700. THE MOST LIKELY RISK WILL
BE STRONG WINDS AND HAVE ADDED GUSTY WIND ENHANCED WORDING FOR
NOW. FOR NORTHERN AROOSTOOK...THE FRONT WILL CROSS TOO EARLY IN THE
DAY AND APPEARS TO MITIGATE THE SEVERE RISK. HIGHS THERE WILL BE
IN THE LOWER 80S. SHOWERS AND THUNDERSTORMS WILL WIND DOWN
WEDNESDAY EVENING FOR BANGOR AND THE DOWN EAST REGION AND COOLER
AIR WILL GRADUALLY FILTER INTO THE REGION LATER IN THE NIGHT INTO
THURSDAY. THURSDAY WILL BE MUCH COOLER WITH HIGHS REACHING AROUND
80F DOWN EAST WITH A NORTHWEST FLOW. FURTHER NORTH IN AROOSTOOK
COUNTY...HIGHS WILL BE CLOSER TO 70F WITH WIDESPREAD CUMULUS
LIMITING SUNSHINE AND A FEW SHOWERS IN THE NW FLOW. A PLEASANTLY
COOL NIGHT APPEARS ON TAP FOR THURSDAY NIGHT WITH LOWS IN THE
UPPER 40S TO LOW 50S. CANADIAN HIGH PRESSURE WILL BE CENTERED
OVER THE REGION ON FRIDAY WITH HIGHS IN THE 70S AND LOW HUMIDITY.
THE HIGH WILL QUICKLY MOVE EAST BY FRIDAY NIGHT AND ALLOW A
FRONTAL SYSTEM TO AFFECT THE STATE NEXT WEEKEND.
&&
.AVIATION /10Z SUNDAY THROUGH THURSDAY/...
NEAR TERM: VFR CONDITIONS WILL DOMINATE TODAY AND TONIGHT. HAVE
REMOVED MORNING FOG FROM TAFS WHICH HAD IT IN EITHER PREVAILING OR
TEMPO GROUP (KHUL, KPQI, AND KCAR), AS MID LEVEL CLOUD DECK HAS
KILLED MOST OF THE RADIATION FOG OR PREVENTED ITS FORMATION.
SHORT TERM: VFR EXCEPT IN THUNDERSTORMS. THUNDERSTORMS COULD
AFFECT FVE TUESDAY NIGHT AND OTHER TERMINALS WEDNESDAY AFTERNOON
AND EVENING.
&&
.MARINE...
NEAR TERM: CONDITIONS WILL REMAIN EASILY BELOW SMALL CRAFT LEVELS
THROUGH TONIGHT. EXPECT A SEA BREEZE UP TO 10 KNOTS THIS AFTERNOON.
SHORT TERM: NO SIGNIFICANT WEATHER OUTSIDE OF INCREASING SOUTH
SWELL TOWARDS WEDNESDAY AND THURSDAY. SWELL IS CURRENTLY EXPECTED
REACH JUST OVER 4 FT. WINDS MAY GUST UP TO 20 KTS AHEAD OF A COLD
FRONT LATE WEDNESDAY. THIS FRONT MAY HAVE SOME THUNDERSTORMS
MOVING OVER THE WATER LATE WEDNESDAY AFTERNOON AND WEDNESDAY EVENING.
&&
.CAR WATCHES/WARNINGS/ADVISORIES...
ME...NONE.
MARINE...NONE.
&&
$$
NEAR TERM...FOISY
SHORT TERM...MCW
LONG TERM...MCW
AVIATION...FOISY/MCW
MARINE...FOISY/MCW
AREA FORECAST DISCUSSION
NWS WAKEFIELD VA
207 PM EDT SUN AUG 24 2014
.SYNOPSIS...
A FRONTAL BOUNDARY PUSHES FARTHER SOUTH OF THE AREA TODAY AS HIGH
PRESSURE REMAINS OVER THE NORTHEAST STATES. THE HIGH WILL BUILD
SOUTH INTO THE MID ATLANTIC MONDAY AND TUESDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
LATEST SFC ANALYSIS REVEALS ~1021 MB HI PRES CENTERED OVR NEW
ENGLAND WITH A FRNTAL BNDRY DROPPING S THRU THE CAROLINAS.
ALOFT...NW FLOW CONTINUES WITH AN UPR-LEVEL RIDGE CENTERED OVR THE
E-CNTRL CONUS. CLOUDS CONTINUE TO SLOWLY MOVE WEST AND MOST
CLOUDINESS IS OVER THE WESTERN MOST COUNTIES. HOWEVER CAN SEE MORE
CU DEVELOPING AND COMING IN OFF THE OCEAN. LOOKING AT THE RAP AND
HRRR BUFKIT SOUNDINGS DOES SHOW MORE PARTLY SUNNY SKIES EAST AND
MADE SOME ADJUSTMENTS TO CLOUD COVER. HELD MAXES ALONG THE COAST
ONLY IN THE MID TO UPPER 70S THIS AFTERNOON. THE WAL SOUNDING
WOULD ONLY SUPPORT A HIGH IN THE MID 70S. WILL BE A LITTLE WARMER
INLAND WITH HIGHS REACHING THE LOW 80S.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH TUESDAY/...
SHORT TERM PERIOD WILL BE CHARACTERIZED BY SFC HI PRES LOCKED IN
PLACE ALONG THE NE AND MID ATLANTIC CST...AND UPR-LEVEL RIDGING
ACROSS THE E HALF OF THE CONUS. THIS WILL LEAD TO DRY CONDITIONS
THE ENTIRE PERIOD WITH NE WINDS AND MSTLY SUNNY/CLEAR SKIES. BLO
NORMAL TEMPS WILL CONTINUE...WITH HIGHS MON AND TUE IN THE UPR 70S
TO MID 80S AND LOWS IN THE UPR 50S TO MID 60S.
&&
.LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/...
THE WX PATTERN THROUGH THE MIDDLE OF NEXT WEEK WILL BE DOMINATED
BY SFC HIGH PRESSURE AND UPPER LEVEL RIDGING ALONG THE EASTERN
SEABOARD. THIS SHOULD KEEP ANY TROPICAL CYCLONE ACTIVITY SHUNTED
WELL SOUTH OF THE REGION THROUGH AT LEAST THURSDAY. THE RIDGING
PATTERN MID-WEEK WILL MAINTAIN A COOL AND DRY AIRMASS OVER THE
AREA THROUGH WED BEFORE THE RIDGE AXES AT THE SFC AND ALOFT ALOFT
BEGIN TO SHIFT EAST OF THE FA...AND MOVING OFFSHORE ON THU. TEMPS
WILL BE SLIGHTLY BELOW NORMAL TUE NIGHT THROUGH WED NIGHT (LOWS IN
THE 60S...UPPER 50S FAR WRN COUNTIES/HIGHS IN THE LOW-MID 80S...
MID-UPPER 70S BEACHES)...THEN SLOWLY MODERATE TWD SEASONAL NORMALS
THU/FRI (HIGHS IN THE MID-UPPER 80S...UPPER 70S-LOWER 80S
BEACHES/LOWS IN THE 60S...AROUND 70 BEACHES). PENDING WX FROM THU
INTO FRI WILL BE HIGHLY DEPENDENT ON TROPICAL ACTIVITY TIMING AND
PLACEMENT. UNCERTAINTY REMAINS HIGH AND PREFER NOT TO LEAN THE
FORECAST HEAVILY TWD ANY GIVEN SOLUTION AT THIS TIME.
&&
.AVIATION /18Z SUNDAY THROUGH FRIDAY/...
DRIER AIR CONTINUES TO OVERSPREAD THE AREA TODAY WITH VFR
CONDITIONS EXPECTED THROUGH THE 18Z TAF PERIOD. GUSTY NE WINDS
ALONG THE COAST BTWN 15-25 KTS WILL PERSIST DURING THE DAYLIGHT
HRS. SKC ALONG WITH DIMINISHING WINDS AFTER 00Z.
OUTLOOK...DRY WEATHER WITH VFR CONDITIONS EXPECTED FOR NEXT SEVERAL
DAYS AS MID AND LOWER RIDGING TAKES PLACE OVER THE AREA.
&&
.MARINE...
HIGH PRESSURE OVER NEW ENGLAND WILL CONTINUE TO BUILD SOUTH AND OVR
THE WATERS THROUGH MID WEEK. PERSISTENT NE FLOW AND TIGHTENING PRS
GRADIENT WILL KEEP SCA FLAGS FLYING TODAY. WINDS DIMINISH ACROSS THE
CHES BAY BY 00Z. MOUTH OF THE CHES BAY AND CURRITUCK SOUND RATHER
PROBLEMATIC AS WINDS REMAIN IN THE 15-20 KT RANGE ALONG WITH WAVES
AT THE MOUTH HOVERING ARND 4 FT THRU MON. EXTENDED HEADLINES OVER
THE COASTAL WATERS THRU MON NIGHT MAINLY FOR SEAS ARND 5 FT OUT
NEAR 20 NM.
NE FLOW BEGINS TO WANE BY TUESDAY AS HIGH PRESSURE MOVES FARTHER
AWAY FROM THE REGION. HOWEVER...UNCERTAINTY EXISTS IN SEA HEIGHT
FORECAST GIVEN INCREASED SWELL FROM A POTENTIAL TROPICAL SYSTEM
PROGGED TO PASS NEAR THE MID ATLANTIC COAST LATER THIS WEEK.
&&
.TIDES/COASTAL FLOODING...
THREAT NOW OVER FOR PAST HIGH TIDE CYCLE. LEWISETTA CAME IN JUST
BELOW THE MINOR FLOODING LEVEL AS TIDES JUMPED UP TO BETWEEN ONE
TO ONE AND A HALF FEET ABOVE NORMAL. TIDES FOR TODAYS HIGH TIDE
CYCLE PROGGED TO BE AROUND ONE FOOT ABOVE NORMAL...SO LEVELS SHOULD
REMAIN BELOW MINOR FLOODING THRESHOLDS THIS AFTN/EARLY EVENING.
LATEST DATA SUGGESTS ANOTHER ROUND OF LEVELS FALLING JUST SHORT
OF MINOR FLOODING AGAIN TONIGHT. THUS...ANOTHER ROUND OF
STATEMENTS MAY BE NEEDED THIS AFTN.
HIGH RIP CURRENT RISK NOW FOR ALL ATLANTIC BEACHES FROM OCEAN CITY
MD DOWN TO OUTER BANKS CURRITUCK NC. SEE CFWAKQ FOR DETAILS.
&&
.AKQ WATCHES/WARNINGS/ADVISORIES...
MD...BEACH HAZARDS STATEMENT UNTIL 8 PM EDT THIS EVENING FOR MDZ025.
NC...BEACH HAZARDS STATEMENT UNTIL 8 PM EDT THIS EVENING FOR NCZ102.
VA...BEACH HAZARDS STATEMENT UNTIL 8 PM EDT THIS EVENING FOR
VAZ098>100.
COASTAL FLOOD ADVISORY FROM MIDNIGHT TONIGHT TO 4 AM EDT
MONDAY FOR VAZ077.
MARINE...SMALL CRAFT ADVISORY UNTIL 4 PM EDT MONDAY FOR ANZ633-634.
SMALL CRAFT ADVISORY UNTIL 7 PM EDT THIS EVENING FOR ANZ632.
SMALL CRAFT ADVISORY UNTIL 4 PM EDT THIS AFTERNOON FOR ANZ630-
631-638.
SMALL CRAFT ADVISORY UNTIL 4 AM EDT TUESDAY FOR ANZ650-652-654-
656-658.
&&
$$
SYNOPSIS...MAS
NEAR TERM...MAS/JAB
SHORT TERM...MAS
LONG TERM...BMD
AVIATION...MPR/DAP
MARINE...MPR
TIDES/COASTAL FLOODING...
AREA FORECAST DISCUSSION
NWS WAKEFIELD VA
1223 PM EDT SUN AUG 24 2014
.SYNOPSIS...
A FRONTAL BOUNDARY PUSHES FARTHER SOUTH OF THE AREA TODAY AS HIGH
PRESSURE REMAINS OVER THE NORTHEAST STATES. THE HIGH WILL BUILD
SOUTH INTO THE MID ATLANTIC MONDAY AND TUESDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
LATEST SFC ANALYSIS REVEALS ~1021 MB HI PRES CENTERED OVR NEW
ENGLAND WITH A FRNTAL BNDRY DROPPING S THRU THE CAROLINAS.
ALOFT...NW FLOW CONTINUES WITH AN UPR-LEVEL RIDGE CENTERED OVR THE
E-CNTRL CONUS. CLOUDS CONTINUE TO SLOWLY MOVE WEST AND MOST
CLOUDINESS IS OVER THE WESTERN MOST COUNTIES. HOWEVER CAN SEE MORE
CU DEVELOPING AND COMING IN OFF THE OCEAN. LOOKING AT THE RAP AND
HRRR BUFKIT SOUNDINGS DOES SHOW MORE PARTLY SUNNY SKIES EAST AND
MADE SOME ADJUSTMENTS TO CLOUD COVER. HELD MAXES ALONG THE COAST
ONLY IN THE MID TO UPPER 70S THIS AFTERNOON. THE WAL SOUNDING
WOULD ONLY SUPPORT A HIGH IN THE MID 70S. WILL BE A LITTLE WARMER
INLAND WITH HIGHS REACHING THE LOW 80S.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH TUESDAY/...
SHORT TERM PERIOD WILL BE CHARACTERIZED BY SFC HI PRES LOCKED IN
PLACE ALONG THE NE AND MID ATLANTIC CST...AND UPR-LEVEL RIDGING
ACROSS THE E HALF OF THE CONUS. THIS WILL LEAD TO DRY CONDITIONS
THE ENTIRE PERIOD WITH NE WINDS AND MSTLY SUNNY/CLEAR SKIES. BLO
NORMAL TEMPS WILL CONTINUE...WITH HIGHS MON AND TUE IN THE UPR 70S
TO MID 80S AND LOWS IN THE UPR 50S TO MID 60S.
&&
.LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/...
THE WX PATTERN THROUGH THE MIDDLE OF NEXT WEEK WILL BE DOMINATED
BY SFC HIGH PRESSURE AND UPPER LEVEL RIDGING ALONG THE EASTERN
SEABOARD. THIS SHOULD KEEP ANY TROPICAL CYCLONE ACTIVITY SHUNTED
WELL SOUTH OF THE REGION THROUGH AT LEAST THURSDAY. THE RIDGING
PATTERN MID-WEEK WILL MAINTAIN A COOL AND DRY AIRMASS OVER THE
AREA THROUGH WED BEFORE THE RIDGE AXES AT THE SFC AND ALOFT ALOFT
BEGIN TO SHIFT EAST OF THE FA...AND MOVING OFFSHORE ON THU. TEMPS
WILL BE SLIGHTLY BELOW NORMAL TUE NIGHT THROUGH WED NIGHT (LOWS IN
THE 60S...UPPER 50S FAR WRN COUNTIES/HIGHS IN THE LOW-MID 80S...
MID-UPPER 70S BEACHES)...THEN SLOWLY MODERATE TWD SEASONAL NORMALS
THU/FRI (HIGHS IN THE MID-UPPER 80S...UPPER 70S-LOWER 80S
BEACHES/LOWS IN THE 60S...AROUND 70 BEACHES). PENDING WX FROM THU
INTO FRI WILL BE HIGHLY DEPENDENT ON TROPICAL ACTIVITY TIMING AND
PLACEMENT. UNCERTAINTY REMAINS HIGH AND PREFER NOT TO LEAN THE
FORECAST HEAVILY TWD ANY GIVEN SOLUTION AT THIS TIME.
&&
.AVIATION /18Z SUNDAY THROUGH FRIDAY/...
CURRENT TRENDS AND LATEST MODEL DATA IN DECENT AGREEMENT THAT THE
DRYER AIR CONTINUES TO OVERSPREAD THE AREA TODAY WITH ANY BKN SC
DECK SCATTERING OUT AFTER 18Z. FORECAST CONCERN WILL BE THE GUSTY
NE WINDS ALONG THE COAST. DATA SUGGESTS GUSTS BTWN 15-25 KTS ACROSS
THE SERN TAF SITES DURING THE DAYLIGHT HRS. SKC ALONG WITH DININISHING
WINDS AFTER 00Z.
OUTLOOK...DRY WEATHER WITH VFR CONDITIONS EXPECTED FOR NEXT SEVERAL
DAYS AS MID AND LOWER RIDGING TAKES PLACE OVER THE AREA.
&&
.MARINE...
HIGH PRESSURE OVER NEW ENGLAND WILL CONTINUE TO BUILD SOUTH AND OVR
THE WATERS THROUGH MID WEEK. PERSISTANT NE FLOW AND TIGHTENING PRS
GRADIENT WILL KEEP SCA FLAGS FLYING TODAY. WINDS DIMINISH ACROSS THE
CHES BAY BY 00Z. MOUTH OF THE CHES BAY AND CURRITUCK SOUND RATHER
PROBLEMATIC AS WINDS REMAIN IN THE 15-20 KT RANGE ALONG WITH WAVES
AT THE MOUTH HOVERING ARND 4 FT THRU MON. EXTENDED HEADLINES OVER
THE COASTAL WATERS THRU MON NIGHT MAINLY FOR SEAS ARND 5 FT OUT
NEAR 20 NM.
NE FLOW BEGINS TO WANE BY TUESDAY AS HIGH PRESSURE MOVES FARTHER
AWAY FROM THE REGION. HOWEVER...UNCERTAINITY EXISTS IN SEA HEIGHT
FORECAST GIVEN INCREASED SWELL FROM A POTENTIAL TROPICAL SYSTEM
PROGGED TO PASS NEAR THE MID ATLANTIC COAST LATER THIS WEEK.
&&
.TIDES/COASTAL FLOODING...
THREAT NOW OVER FOR PAST HIGH TIDE CYCLE. LEWISETTA CAME IN JUST
BELOW THE MINOR FLOODING LEVEL AS TIDES JUMPED UP TO BETWEEN ONE
TO ONE AND A HALF FEET ABOVE NORMAL. TIDES FOR TODAYS HIGH TIDE
CYCLE PROGGED TO BE AROUND ONE FOOT ABOVE NORMAL...SO LEVELS SHOULD
REMAIN BELOW MINOR FLOODING THRESHOLDS THIS AFTN/EARLY EVENING.
LATEST DATA SUGGESTS ANOTHER ROUND OF LEVELS FALLING JUST SHORT
OF MINOR FLOODING AGAIN TONIGHT. THUS...ANOTHER ROUND OF
STATEMENTS MAY BE NEEDED THIS AFTN.
HIGH RIP CURRENT RISK NOW FOR ALL ATLANTIC BEACHES FROM OCEAN CITY
MD DOWN TO OUTER BANKS CURRITUCK NC. SEE CFWAKQ FOR DETAILS.
&&
.AKQ WATCHES/WARNINGS/ADVISORIES...
MD...BEACH HAZARDS STATEMENT UNTIL 8 PM EDT THIS EVENING FOR MDZ025.
NC...BEACH HAZARDS STATEMENT UNTIL 8 PM EDT THIS EVENING FOR NCZ102.
VA...BEACH HAZARDS STATEMENT UNTIL 8 PM EDT THIS EVENING FOR
VAZ098>100.
MARINE...SMALL CRAFT ADVISORY UNTIL 4 PM EDT MONDAY FOR ANZ633-634.
SMALL CRAFT ADVISORY UNTIL 7 PM EDT THIS EVENING FOR ANZ632.
SMALL CRAFT ADVISORY UNTIL 4 PM EDT THIS AFTERNOON FOR ANZ630-
631-638.
SMALL CRAFT ADVISORY UNTIL 4 AM EDT TUESDAY FOR ANZ650-652-654-
656-658.
&&
$$
SYNOPSIS...MAS
NEAR TERM...MAS/JAB
SHORT TERM...MAS
LONG TERM...BMD
AVIATION...MPR
MARINE...MPR
TIDES/COASTAL FLOODING...BMD
AREA FORECAST DISCUSSION
NWS WAKEFIELD VA
958 AM EDT SUN AUG 24 2014
.SYNOPSIS...
A FRONTAL BOUNDARY PUSHES FARTHER SOUTH OF THE AREA TODAY AS HIGH
PRESSURE REMAINS OVER THE NORTHEAST STATES. THE HIGH WILL BUILD
SOUTH INTO THE MID ATLANTIC MONDAY AND TUESDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
LATEST SFC ANALYSIS REVEALS ~1021 MB HI PRES CENTERED OVR NEW
ENGLAND WITH A FRNTAL BNDRY DROPPING S THRU THE CAROLINAS.
ALOFT...NW FLOW CONTINUES WITH AN UPR-LEVEL RIDGE CENTERED OVR THE
E-CNTRL CONUS. CLOUDS CONTINUE TO SLOWLY MOVE WEST AND MOST
CLOUDINESS IS OVER THE WESTERN MOST COUNTIES. HOWEVER CAN SEE MORE
CU DEVELOPING AND COMING IN OFF THE OCEAN. LOOKING AT THE RAP AND
HRRR BUFKIT SOUNDINGS DOES SHOW MORE PARTLY SUNNY SKIES EAST AND
MADE SOME ADJUSTMENTS TO CLOUD COVER. HELD MAXES ALONG THE COAST
ONLY IN THE MID TO UPPER 70S THIS AFTERNOON. THE WAL SOUNDING
WOULD ONLY SUPPORT A HIGH IN THE MID 70S. WILL BE A LITTLE WARMER
INLAND WITH HIGHS REACHING THE LOW 80S.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH TUESDAY/...
SHORT TERM PERIOD WILL BE CHARACTERIZED BY SFC HI PRES LOCKED IN
PLACE ALONG THE NE AND MID ATLANTIC CST...AND UPR-LEVEL RIDGING
ACROSS THE E HALF OF THE CONUS. THIS WILL LEAD TO DRY CONDITIONS
THE ENTIRE PERIOD WITH NE WINDS AND MSTLY SUNNY/CLEAR SKIES. BLO
NORMAL TEMPS WILL CONTINUE...WITH HIGHS MON AND TUE IN THE UPR 70S
TO MID 80S AND LOWS IN THE UPR 50S TO MID 60S.
&&
.LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/...
THE WX PATTERN THROUGH THE MIDDLE OF NEXT WEEK WILL BE DOMINATED
BY SFC HIGH PRESSURE AND UPPER LEVEL RIDGING ALONG THE EASTERN
SEABOARD. THIS SHOULD KEEP ANY TROPICAL CYCLONE ACTIVITY SHUNTED
WELL SOUTH OF THE REGION THROUGH AT LEAST THURSDAY. THE RIDGING
PATTERN MID-WEEK WILL MAINTAIN A COOL AND DRY AIRMASS OVER THE
AREA THROUGH WED BEFORE THE RIDGE AXES AT THE SFC AND ALOFT ALOFT
BEGIN TO SHIFT EAST OF THE FA...AND MOVING OFFSHORE ON THU. TEMPS
WILL BE SLIGHTLY BELOW NORMAL TUE NIGHT THROUGH WED NIGHT (LOWS IN
THE 60S...UPPER 50S FAR WRN COUNTIES/HIGHS IN THE LOW-MID 80S...
MID-UPPER 70S BEACHES)...THEN SLOWLY MODERATE TWD SEASONAL NORMALS
THU/FRI (HIGHS IN THE MID-UPPER 80S...UPPER 70S-LOWER 80S
BEACHES/LOWS IN THE 60S...AROUND 70 BEACHES). PENDING WX FROM THU
INTO FRI WILL BE HIGHLY DEPENDENT ON TROPICAL ACTIVITY TIMING AND
PLACEMENT. UNCERTAINTY REMAINS HIGH AND PREFER NOT TO LEAN THE
FORECAST HEAVILY TWD ANY GIVEN SOLUTION AT THIS TIME.
&&
.AVIATION /14Z SUNDAY THROUGH THURSDAY/...
CURRENT TRENDS AND LATEST MODEL DATA IN DECENT AGREEMENT THAT THE
DRYER AIR CONTINUES TO OVERSPREAD THE AREA TODAY WITH ANY BKN SC
DECK SCATTERING OUT AFTER 18Z. FORECAST CONCERN WILL BE THE GUSTY
NE WINDS ALONG THE COAST. DATA SUGGESTS GUSTS BTWN 15-25 KTS ACROSS
THE SERN TAF SITES DURING THE DAYLIGHT HRS. SKC ALONG WITH DININISHING
WINDS AFTER 00Z.
OUTLOOK...DRY WEATHER WITH VFR CONDITIONS EXPECTED FOR NEXT SEVERAL
DAYS AS MID AND LOWER RIDGING TAKES PLACE OVER THE AREA.
&&
.MARINE...
HIGH PRESSURE OVER NEW ENGLAND WILL CONTINUE TO BUILD SOUTH AND OVR
THE WATERS THROUGH MID WEEK. PERSISTANT NE FLOW AND TIGHTENING PRS
GRADIENT WILL KEEP SCA FLAGS FLYING TODAY. WINDS DIMINISH ACROSS THE
CHES BAY BY 00Z. MOUTH OF THE CHES BAY AND CURRITUCK SOUND RATHER
PROBLEMATIC AS WINDS REMAIN IN THE 15-20 KT RANGE ALONG WITH WAVES
AT THE MOUTH HOVERING ARND 4 FT THRU MON. EXTENDED HEADLINES OVER
THE COASTAL WATERS THRU MON NIGHT MAINLY FOR SEAS ARND 5 FT OUT
NEAR 20 NM.
NE FLOW BEGINS TO WANE BY TUESDAY AS HIGH PRESSURE MOVES FARTHER
AWAY FROM THE REGION. HOWEVER...UNCERTAINITY EXISTS IN SEA HEIGHT
FORECAST GIVEN INCREASED SWELL FROM A POTENTIAL TROPICAL SYSTEM
PROGGED TO PASS NEAR THE MID ATLANTIC COAST LATER THIS WEEK.
&&
.TIDES/COASTAL FLOODING...
THREAT NOW OVER FOR PAST HIGH TIDE CYCLE. LEWISETTA CAME IN JUST
BELOW THE MINOR FLOODING LEVEL AS TIDES JUMPED UP TO BETWEEN ONE
TO ONE AND A HALF FEET ABOVE NORMAL. TIDES FOR TODAYS HIGH TIDE
CYCLE PROGGED TO BE AROUND ONE FOOT ABOVE NORMAL...SO LEVELS SHUD
REMAIN BELOW MINOR FLOODING THRESHOLDS. LATEST DATA SUGGESTS ANOTHER
ROUND OF LEVELS FALLING JUST SHORT OF MINOR FLOODING AGAIN TONIGHT.
THUS...ANOTHER ROUND OF STATEMENTS MAY BE NEEDED THIS AFTRN.
MODERATE RIP CURRENT THREAT FOR DELMARVA BEACHES WITH A HIGH RIP
CURRENT RISK FOR VA BEACH / OUTER BANKS CURRITUCK TODAY. SEE CFWAKQ
FOR DETAILS.
&&
.AKQ WATCHES/WARNINGS/ADVISORIES...
MD...MODERATE RIP CURRENT RISK UNTIL 8 PM EDT THIS EVENING FOR
MDZ025.
NC...BEACH HAZARDS STATEMENT UNTIL 8 PM EDT THIS EVENING FOR NCZ102.
VA...BEACH HAZARDS STATEMENT UNTIL 8 PM EDT THIS EVENING FOR VAZ098.
MODERATE RIP CURRENT RISK UNTIL 8 PM EDT THIS EVENING FOR
VAZ099-100.
MARINE...SMALL CRAFT ADVISORY UNTIL 4 PM EDT MONDAY FOR ANZ633-634.
SMALL CRAFT ADVISORY UNTIL 7 PM EDT THIS EVENING FOR ANZ632.
SMALL CRAFT ADVISORY UNTIL 4 PM EDT THIS AFTERNOON FOR ANZ630-
631-638.
SMALL CRAFT ADVISORY UNTIL 4 AM EDT TUESDAY FOR ANZ650-652-654-
656-658.
&&
$$
SYNOPSIS...MAS
NEAR TERM...MAS/JAB
SHORT TERM...MAS
LONG TERM...BMD
AVIATION...MPR
MARINE...MPR
TIDES/COASTAL FLOODING...
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
344 PM EDT SUN AUG 24 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 524 AM EDT SUN AUG 24 2014
WATER VAPOR IMAGERY AND RUC ANALYSIS SHOW A TROF OVER THE ROCKIES
WITH DOWNSTREAM RIDGE EXTENDING N THRU THE GREAT LAKES. IN THE
TROF...A VIGOROUS SHORTWAVE WAS LIFTING THRU WY INTO ERN MT/FAR WRN
DAKOTAS. AHEAD OF THIS MAIN FEATURE...ANOTHER SHORTWAVE WAS LIFTING
THRU THE ERN DAKOTAS INTO MANITOBA. SHRA/TSRA HAVE BEEN LINED UP
WITH THIS WAVE ACROSS THE ERN DAKOTAS/WRN MN. LOW-LEVEL JET AHEAD OF
FEATURE HAS ALSO GENERATED SHRA FARTHER E IN NE MN INTO ADJACENT NRN
ONTARIO. CLOSER TO HOME...IT HAS BEEN A QUIET NIGHT. THERE HAVE BEEN
SOME SPRINKLES AT TIMES OVER THE W HALF OF UPPER MI AND PERHAPS A
BRIEF -SHRA OVER THE FAR W...PROBABLY TIED TO ERN EDGE OF LOW-LEVEL
JET. OTHERWISE...MOSTLY CLOUDY SKIES HAVE BEEN THE RULE OVER THE W
AND PARTLY CLOUDY E.
TODAY...SCT SPRINKLES/PERHAPS A -SHRA OVER THE W WILL END THIS
MORNING AS LOW-LEVEL JET LIFTS N. OTHERWISE...LOOKS LIKE A DRY DAY
IS ON THE WAY. APPROACHING COLD FRONT TODAY WILL REMAIN WELL W OF
UPPER MI WITH THE ROUGHLY N-S ORIENTED FRONT ONLY HALFWAY ACROSS MN
BY 00Z THIS EVENING. FCST SOUNDINGS ALSO SUGGEST A CAPPED
ENVIRONMENT WITH 850MB THERMAL RIDGE NOSING INTO THE AREA. SINCE
THERE IS ESSENTIALLY NO FORCING WITH MID/UPPER RIDGE HOLDING (NO
HEIGHT FALLS)...WILL CARRY DRY WEATHER THRU THE AFTN HRS. MAY BE
ABLE TO GET A FEW MORE BREAKS IN THE CLOUDS TODAY TO BOOST TEMPS
SOME. FCST REFLECTS THIS IDEA WITH MAX TEMPS MOSTLY IN THE UPPER
70S/LWR 80S. WILL BE A LITTLE COOLER IF CLOUDS CONTINUE TO BE MORE
PERSISTENT.
AS COLD FRONT PROGRESSES EASTWARD TONIGHT...HEIGHT FALLS SPREADING
OVERTOP ABUNDANT INSTABILITY (MLCAPE OF 1500-3000J/KG) SHOULD YIELD
RAPID TSTM DEVELOPMENT ALONG FRONT THIS EVENING IN MN. HIGH RES NAM
WINDOW...NCEP WRF ARW AND NMM AS WELL AS NSSL WRF ALL LOOK QUITE
REASONABLE WITH EXPECTATIONS. THE BIG QUESTION IS HOW THE STORMS
HOLD TOGETHER WHILE MOVING E INTO UPPER MI DURING THE NORMAL
NIGHTTIME DOWNWARD MLCAPE CYCLE. ALSO IN THIS CASE...DEEP LAYER
FORCING IS WEAK WHICH MAY FURTHER HASTEN A WEAKENING TREND DURING
THE NIGHT. AT THIS POINT...THE W HAS THE BEST CHC OF SEEING
CONVECTION GIVEN ARRIVAL EARLIER IN THE NIGHT. WITH DEEP LAYER SHEAR
INCREASING TO 30-40KT...STRONG STORMS AND PERHAPS AN ISOLD SVR ARE
POSSIBLE OVER THE FAR W IF STORMS ARRIVE EARLY ENOUGH BEFORE
INSTABILITY BEGINS DIMINISHING. WILL CARRY SHRA/TSRA CHANCES
EASTWARD DURING THE NIGHT...BUT WITH A GRADUAL LOWERING OF POPS.
.LONG TERM...(MONDAY NIGHT THROUGH SUNDAY)
ISSUED AT 343 PM EDT SUN AUG 24 2014
A TRANSITION TO A COOLER AND MAINLY DRIER PATTERN WL BE IN STORE
THIS WEEK AS THE UPPER PATTERN TRANSITIONS TO A LOWER AMPLITUDE/MORE
ZONAL FLOW ALONG THE CNDN BORDER. OVER THE PAST COUPLE OF DAYS...
THERE HAVE BEEN SOME MODEL DIFFERENCES ON WHETHER THERE WOULD BE
SOME INTERACTION BTWN THIS NRN BRANCH FLOW AND A WEAKER SRN STREAM
IN THE CONUS. ALTHOUGH THE TREND THRU MID WEEK IS FOR A MORE ROBUST
AND DRIER NRN STREAM FLOW...LONGER TERM MODEL DIFFERENCES AND
RUN-TO-RUN INCONSISTENCIES RETURN FOR LATER IN THE WEEK.
MON NGT...THE CWA WL BE UNDER A SLOWLY VEERING WSW FLOW ALF TO THE S
OF VIGOROUS SHRTWV MOVING EWD THRU FAR NW ONTARIO. ALTHOUGH
ATTENDANT COLD FNT OVER THE SE CWA WL BE WEAKENING...GUIDANCE HINTS
A SECOND COLD FNT PUSHED ALONG BY A TRAILING UPR DISTURBANCE THAT IS
EMBEDDED IN THE VEERING FLOW ALF AND STREAKING ACRS NRN LK SUP/
ADJOINING ONTARIO WILL SURGE ACRS THE CWA. COMBO OF DRY AIR ALF AND
DIURNAL COOLING WL LIMIT PCPN CHCS ASSOCIATED WITH THIS SECONDARY
COLD FROPA...BUT WL INCLUDE SOME LO CHC POPS OVER MAINLY THE E HALF
OF THE CWA CLOSER TO TRACK OF TRAILING SHRTWV AND/OR WEAKENING
PRIMARY FNT/LINGERING HIER H85 DEWPTS NEAR 12-14C UNDER AREA OF
DEEP...ALBEIT RATHER WEAK DEEP LYR QVECTOR CNVGC ASSOCIATED WITH THE
SECOND SHRTWV. THE 12Z NAM IS MOST AGGRESSIVE WITH THE LLVL COOLING
BEHIND THE FROPA...SHOWING H85 TEMPS FALLING AS LO AS 5C OVER THE
FAR NW BY 12Z TUE. SO MIN TEMPS WL BE QUITE A BIT LOWER THAN
TNGT...ESPECIALLY OVER THE WRN CWA.
TUE...HI PRES AND MUCH DRIER AIR WITH PWAT FALLING AS LO AS 0.50 TO
1.00 INCH OVER THE S WL ARRIVE ACRS UPR MI. ALTHOUGH THERE MAY BE
SOME MID/HI CLDS OVER MAINLY THE SRN TIER ASSOCIATED WITH A SRN
STREAM WEAK DISTURBANCE PASSING THRU THE LOWER LKS...GUIDANCE HINTS
THE AIRMASS BLO H7 WL BE TOO DRY FOR ANY PCPN SO FAR N OF SFC BNDRY
IN THE LOWER LKS. THE ONE EXCEPTION WAS THE 00Z CNDN MODEL WHICH
INDICATED THE DEEPER MSTR TO THE S WOULD RETURN FARTHER N AHEAD OF
YET ANOTHER SHRTWV MOVING ALONG THE CNDN BORDER AND BRING SOME PCPN
TO THE SE CWA...BUT THE 12Z VERSION HAS BACKED OFF ON THIS WETTER
SCENARIO. H85 TEMPS VARYING FM ARND 8C OVER THE NW TO ARND 13C OVER
THE SCNTRL WL SUPPORT HI TEMPS FM THE 60S NEAR LK SUP TO NEAR 80
WITH SOME DOWNSLOPING INTO MENOMINEE COUNTY.
TUE NGT/WED...BULK OF THE LONGER TERM MODELS INDICATE A MORE WNW
CONFLUENT FLOW ALF AHEAD OF SHRTWV RDG EMBEDDED IN THE NRN STREAM
ALONG THE CNDN BORDER WL BRING HI PRES/DRY AIR TO THE UPR LKS AND
SUPPRESS DEEPER MSTR TO THE S. THE 12Z CNDN MODEL DOES HINT AT SOME
MID/HI CLDS LINGERING INTO WED ON THE NRN EDGE OF SHRTWV PASSING TO
THE S IN THE SRN STREAM...BUT ITS FCST LLVLS ARE TOO DRY FOR PCPN.
TUE NGT WL BE PLEASANTLY COOL AS H85 TEMPS ARE FCST TO BE ARND
8C/PWAT 0.50-0.75 INCH. WITH DRY AIR AND H85 TEMPS IN THE 8-10C
RANGE ON WED...EXPECT MOSUNNY CONDITIONS AND HI TEMPS IN THE LO 70S
OVER THE INTERIOR AWAY FM LK MODERATION.
WED NGT/THU...DRY HI PRES SHIFTING TO OVER SE ONTARIO IS FCST TO
DOMINATE AND BRING CONTINUED DRY WX TO UPR MI. AFTER ANOTHER COOL
NGT...TEMPS ON THU SHOULD BE A FEW DEGREES HIER THAN ON WED AS H85
TEMPS REBOUND TO 10-12C IN LGT RETURN SSW FLOW ARND DEPARTING SFC HI
PRES.
EXTENDED...SHRTWV/DEEPER MSTR ASSOCIATED WITH SRN BRANCH FLOW IS
FCST TO AT LEAST SKIRT THE SRN TIER OF THE CWA IN THE THU NGT TO FRI
NGT TIME PERIOD BEFORE A COLD FNT ASSOCIATED WITH A SHRTWV MOVING
THRU THE WNW NRN BRANCH FLOW CROSSES UPR MI ON SAT AND DRIVES THIS
MSTR TO THE S. GIVEN SOME TIMING/TRACK DIFFERENCES ON VARIOUS
SHRTWVS...WL CARRY NO MORE THAN THE CONSENSUS LO CHC POPS. DRY WX
SHOULD BE THE RULE NEXT SUN WITH HI PRES FOLLOWING THE SAT FROPA.
TEMPS DURING THIS TIME ARE LIKELY TO RUN AOB NORMAL.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON)
ISSUED AT 223 PM EDT SUN AUG 24 2014
WHILE DAYTIME HEATING HAS BEEN EFFECTIVE AT BRINGING HIGH END MVFR
TO VFR CONDITIONS TO IWD AND CMX. OTHERWISE...PERSISTENT S-SE WINDS
HAVE KEEP MVFR CLINGS GOING A BIT LONGER AT SAW. LOOK FOR SOME
IMPROVEMENT AT SAW THIS AFTERNOON. THE MAIN STORY FOR THIS TAF
PERIOD WILL BE THE NEARING COLD FRONT COLD FRONT APPROACHING FROM
THE W LATE THIS EVENING...BRINGING SHRA/TSRA TO W UPPER MI. KEPT A
MENTION OF VCTS AT KIWD...AS TS ACTIVITY SHOULD BE DIMINISHING
OVERNIGHT DUE TO DECREASING INSTABILITY. ONLY -SHRA HAVE BEEN
INCLUDED AT CMX FROM 06-10Z...NO TS. PLENTY OF MOISTURE WILL REMAIN
WITH UPSLOPE CONDITIONS BRINGING ANOTHER ROUND OF MAINLY MVFR
CEILINGS TO SAW OVERNIGHT. OTHERWISE...LOOK FOR SLOWLY IMPROVING
CONDITIONS W TO E ON MONDAY AS DRIER AIR WORKS IN FROM THE W BEHIND
THE EXITING COLD FRONT.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 524 AM EDT SUN AUG 24 2014
FOG MAY BE AN ISSUE OVER PORTIONS OF LAKE SUPERIOR THRU MON GIVEN
THE HUMID AIR MASS THAT CONTINUES TO LINGER OVER THE AREA. PASSAGE
OF A COLD FRONT MON WILL THEN WORK TO CLEAR OUT ANY FOG FROM W TO E
AS DRIER AIR FLOWS INTO THE UPPER LAKES. AHEAD OF THE COLD FRONT...E
TO SE WINDS WILL INCREASE SOME TODAY/TONIGHT. WINDS OF 15-25KT SHOULD
BE OBSERVED AT SOME OF THE HIGHER OBS PLATFORMS. IN THE WAKE OF THE
FRONT...WSW WINDS OF 15-25KT WILL DEVELOP OVER THE W HALF OF THE
LAKE ON MON. HIGH PRES WILL THEN SETTLE INTO THE UPPER LAKES LATE
TUE THRU THU...BRINGING A PERIOD OF LIGHTER WINDS MOSTLY UNDER 15KT.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...ROLFSON
LONG TERM...KC
AVIATION...KF
MARINE...ROLFSON
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
224 PM EDT SUN AUG 24 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 524 AM EDT SUN AUG 24 2014
WATER VAPOR IMAGERY AND RUC ANALYSIS SHOW A TROF OVER THE ROCKIES
WITH DOWNSTREAM RIDGE EXTENDING N THRU THE GREAT LAKES. IN THE
TROF...A VIGOROUS SHORTWAVE WAS LIFTING THRU WY INTO ERN MT/FAR WRN
DAKOTAS. AHEAD OF THIS MAIN FEATURE...ANOTHER SHORTWAVE WAS LIFTING
THRU THE ERN DAKOTAS INTO MANITOBA. SHRA/TSRA HAVE BEEN LINED UP
WITH THIS WAVE ACROSS THE ERN DAKOTAS/WRN MN. LOW-LEVEL JET AHEAD OF
FEATURE HAS ALSO GENERATED SHRA FARTHER E IN NE MN INTO ADJACENT NRN
ONTARIO. CLOSER TO HOME...IT HAS BEEN A QUIET NIGHT. THERE HAVE BEEN
SOME SPRINKLES AT TIMES OVER THE W HALF OF UPPER MI AND PERHAPS A
BRIEF -SHRA OVER THE FAR W...PROBABLY TIED TO ERN EDGE OF LOW-LEVEL
JET. OTHERWISE...MOSTLY CLOUDY SKIES HAVE BEEN THE RULE OVER THE W
AND PARTLY CLOUDY E.
TODAY...SCT SPRINKLES/PERHAPS A -SHRA OVER THE W WILL END THIS
MORNING AS LOW-LEVEL JET LIFTS N. OTHERWISE...LOOKS LIKE A DRY DAY
IS ON THE WAY. APPROACHING COLD FRONT TODAY WILL REMAIN WELL W OF
UPPER MI WITH THE ROUGHLY N-S ORIENTED FRONT ONLY HALFWAY ACROSS MN
BY 00Z THIS EVENING. FCST SOUNDINGS ALSO SUGGEST A CAPPED
ENVIRONMENT WITH 850MB THERMAL RIDGE NOSING INTO THE AREA. SINCE
THERE IS ESSENTIALLY NO FORCING WITH MID/UPPER RIDGE HOLDING (NO
HEIGHT FALLS)...WILL CARRY DRY WEATHER THRU THE AFTN HRS. MAY BE
ABLE TO GET A FEW MORE BREAKS IN THE CLOUDS TODAY TO BOOST TEMPS
SOME. FCST REFLECTS THIS IDEA WITH MAX TEMPS MOSTLY IN THE UPPER
70S/LWR 80S. WILL BE A LITTLE COOLER IF CLOUDS CONTINUE TO BE MORE
PERSISTENT.
AS COLD FRONT PROGRESSES EASTWARD TONIGHT...HEIGHT FALLS SPREADING
OVERTOP ABUNDANT INSTABILITY (MLCAPE OF 1500-3000J/KG) SHOULD YIELD
RAPID TSTM DEVELOPMENT ALONG FRONT THIS EVENING IN MN. HIGH RES NAM
WINDOW...NCEP WRF ARW AND NMM AS WELL AS NSSL WRF ALL LOOK QUITE
REASONABLE WITH EXPECTATIONS. THE BIG QUESTION IS HOW THE STORMS
HOLD TOGETHER WHILE MOVING E INTO UPPER MI DURING THE NORMAL
NIGHTTIME DOWNWARD MLCAPE CYCLE. ALSO IN THIS CASE...DEEP LAYER
FORCING IS WEAK WHICH MAY FURTHER HASTEN A WEAKENING TREND DURING
THE NIGHT. AT THIS POINT...THE W HAS THE BEST CHC OF SEEING
CONVECTION GIVEN ARRIVAL EARLIER IN THE NIGHT. WITH DEEP LAYER SHEAR
INCREASING TO 30-40KT...STRONG STORMS AND PERHAPS AN ISOLD SVR ARE
POSSIBLE OVER THE FAR W IF STORMS ARRIVE EARLY ENOUGH BEFORE
INSTABILITY BEGINS DIMINISHING. WILL CARRY SHRA/TSRA CHANCES
EASTWARD DURING THE NIGHT...BUT WITH A GRADUAL LOWERING OF POPS.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 354 AM EDT SUN AUG 24 2014
AFTER A VERY CLOUDY PERIOD OVER THE UPPER GREAT LAKES REGION OVER
THE LAST 7-9 DAYS...EXPECT A TRANSITION TO DRIER...COOLER AND MORE
SUNSHINE FOR THE MIDDLE OF THE WORK WEEK.
THE TRANSITION WILL BE LED BY A COLD FRONT THAT WILL BE MOVING
THROUGH THE CWA MONDAY MORNING AND EARLY AFTERNOON. THIS FRONT IS
ASSOCIATED WITH 1002MB LOW PRESSURE SYSTEM THAT WILL BE MOVING FROM
NEAR LAKE WINNIPEG ON MONDAY MORNING TO JAMES BAY ON MONDAY NIGHT.
AS THIS OCCURS...AN OCCLUDED FRONT WILL STRETCH EAST INTO NORTHERN
ONTARIO AND THEN A COLD FRONT STRETCHING SOUTH ACROSS WEST/CENTRAL
LAKE SUPERIOR AND UPPER MICHIGAN AROUND 12Z ON MONDAY. EXPECT
SHOWERS AND THUNDERSTORMS TO BE ONGOING MONDAY MORNING ALONG THE
FRONT AND SHIFTING EAST THROUGH THE MORNING AND EARLY AFTERNOON
HOURS. CURRENT FORECAST CALLS FOR THE FRONT AND ASSOCIATED
SHOWERS/THUNDERSTORMS TO BE EXITING THE EASTERN CWA TOWARDS THE LATE
AFTERNOON. WHILE THERE IS HIGH CONFIDENCE ON THE TIMING OF THE COLD
FRONT MOVING THROUGH (ALTHOUGH 00Z NAM HAS SLOWED THE FRONT
DOWN A FEW HOURS)...THE AMOUNT OF SHOWERS/THUNDERSTORMS ALONG THE
FRONT IS UNCERTAIN DUE TO SEVERAL LIMITATIONS. THESE LIMITATIONS
INCLUDE THE TIME OF DAY THE FRONT IS MOVING THROUGH...MUCH OF THE
FORCING FROM THE UPPER TROUGH AND SHORTWAVES WELL TO THE NORTHWEST
AND NEAR THE SURFACE LOW...ALONG WITH LIMITED MOISTURE AND WEAK
LAPSE RATES (AROUND 6C/KM) IN THE MID LEVELS. IN ADDITION...A NOSE
OF DRY AIR MOVING IN BETWEEN 900-700MB WILL HELP TO LIMIT ANY
SURFACE OR LOW LEVEL DEVELOPMENT. THESE FACTORS COMBINE TO KEEP POPS
ON THE LOW END OF CHANCES AS THE FRONT MOVES THROUGH AND THINK THE
BEST OPPORTUNITY FOR SHOWERS/THUNDERSTORMS WILL COME FROM ANY
ONGOING STORMS MOVING INTO THE AREA FROM THE WEST TONIGHT AND TRYING
TO HOLD TOGETHER INTO MONDAY. IF SOMETHING CAN HOLD TOGETHER OR GET
GOING AS THE FRONT MOVES INTO THE EASTERN CWA MONDAY
AFTERNOON...THERE COULD BE STRONG THUNDERSTORMS WITH INSTABILITY ON
THE INCREASE (MU/ML CAPES INCREASING TO 500-1500 J/KG) AND 0-6KM
SHEAR VALUES AROUND 35KTS (OR 25-30KTS OF EFFECTIVE BASED OFF
POTENTIAL FOR ELEVATED THUNDERSTORMS). WEST OF THE COLD FRONT ON
MONDAY...WILL SEE MUCH DRIER AIR MOVING IN AND DEWPOINTS FALLING
INTO THE 50S AND SKIES BECOMING MOSTLY SUNNY.
THE LOW LEVEL WEDGE OF DRY AIR WILL REMAIN INTO MONDAY NIGHT
(PRODUCING PARTLY CLOUDY TO MOSTLY CLEAR SKIES) BEFORE 925-700MB
WINDS TURN MORE TO THE WEST AND EVENTUALLY WEST-NORTHWEST AS A
SECONDARY FRONT/TROUGH MOVES THROUGH. THERE COULD BE SOME SHOWERS
OVER THE SOUTHEAST CWA WITH THIS SECONDARY FRONT AND CLOSER TO
LINGERING MOISTURE FROM THE FIRST FRONT. BEHIND THE SECONDARY
FRONT...MODELS ARE INDICATING AN INCREASE IN 925-850MB MOISTURE
THAT WILL LEAD TO DIURNAL CLOUD DEVELOPMENT DURING THE DAY ON
TUESDAY OVER THE NORTH HALF OF THE LAND CWA EVEN THOUGH A HIGH
PRESSURE RIDGE (FROM A HIGH IN THE EASTERN DAKOTAS) WILL NOSE EAST
OVER THE WESTERN HALF OF THE CWA. FARTHER SOUTH...WOULD EXPECT
MOSTLY SUNNY SKIES AS THE COLD FRONT LOOKS TO SLIDE FAR ENOUGH SOUTH
INTO LOWER MICHIGAN AND SOUTHERN WISCONSIN TO KEEP ANY SHOWERS TO
THE SOUTH OF THE AREA. HIGH TEMPERATURES WILL BE ABOUT 10 DEGREES
COOLER ON TUESDAY THAN MONDAY...WITH HIGHS INT HE MID 70S OVER THE
SOUTHEAST HALF AND UPPER 60S OVER THE WEST NEAR LAKE SUPERIOR.
WITH THE FLOW BECOMING ZONAL FOR THE MIDDLE OF THE UPCOMING WORK
WEEK AND THE MAIN SHORTWAVES STAYING NORTH OF THE CWA AND MOVING
ACROSS NORTHERN ONTARIO...EXPECT THE HIGH PRESSURE TO FOLLOW THE
RIDGE EASTWARD WEDNESDAY INTO THURSDAY. THIS WILL PRODUCE DRY
WEATHER AND WITH 850MB TEMPS SLIGHTLY BELOW NORMAL (AROUND
9C) EXPECT HIGHS TO BE SIMILAR WITH RESPECT TO NORMAL. WILL MENTION
THAT THE SOUTH CENTRAL CWA COULD BE BRUSHED BY A FEW WEAK WAVES
RUNNING ALONG THAT FRONT TO THE SOUTH OF THE AREA ON TUESDAY
AND AGAIN THURSDAY...BUT WOULDN/T EXPECT MORE THAN A STRAY SHOWER.
THE HIGH PRESSURE RIDGE WILL BEGIN TO SLIDE EAST ON FRIDAY WHILE AN
UPPER TROUGH SEPARATED FROM THE NORTHERN STREAM FLOW SLIDES EAST
INTO THE CENTRAL PLAINS. THIS WAVE WILL DEVELOP A WEAK SURFACE LOW
IN THE CENTRAL PLAINS AND SLIDE EAST-NORTHEAST THROUGH THE GREAT
LAKES REGION FRIDAY AFTERNOON INTO FRIDAY NIGHT. 00Z GEM
IS CONSISTENT WITH PREVIOUS RUNS AND 00Z ECMWF ON A SLOWER
ARRIVAL WITH THE UPPER TROUGH AND SURFACE LOW...WHILE THE 00Z GFS
LOOKS TO HAVE CONVECTIVE FEEDBACK ISSUES IN THE CENTRAL PLAINS ON
MONDAY/TUESDAY EVENING WHICH SPEEDS UP THE UPPER TROUGH AND
PUSHES IT THROUGH 12-24HRS EARLIER. FEEL A GENERAL CONSENSUS AND
FOCUS TOWARDS THE ECMWF (AND THE MATCHING TIMING WITH THE GEM) IS A
GOOD MIDDLE POINT RIGHT NOW AND WILL FOLLOW THAT IDEA. THIS WAVE
WILL SHIFT EAST OF THE AREA ON SATURDAY AND LEAD TO DRY WEATHER.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON)
ISSUED AT 223 PM EDT SUN AUG 24 2014
WHILE DAYTIME HEATING HAS BEEN EFFECTIVE AT BRINGING HIGH END MVFR
TO VFR CONDITIONS TO IWD AND CMX. OTHERWISE...PERSISTENT S-SE WINDS
HAVE KEEP MVFR CLINGS GOING A BIT LONGER AT SAW. LOOK FOR SOME
IMPROVEMENT AT SAW THIS AFTERNOON. THE MAIN STORY FOR THIS TAF
PERIOD WILL BE THE NEARING COLD FRONT COLD FRONT APPROACHING FROM
THE W LATE THIS EVENING...BRINGING SHRA/TSRA TO W UPPER MI. KEPT A
MENTION OF VCTS AT KIWD...AS TS ACTIVITY SHOULD BE DIMINISHING
OVERNIGHT DUE TO DECREASING INSTABILITY. ONLY -SHRA HAVE BEEN
INCLUDED AT CMX FROM 06-10Z...NO TS. PLENTY OF MOISTURE WILL REMAIN
WITH UPSLOPE CONDITIONS BRINGING ANOTHER ROUND OF MAINLY MVFR
CEILINGS TO SAW OVERNIGHT. OTHERWISE...LOOK FOR SLOWLY IMPROVING
CONDITIONS W TO E ON MONDAY AS DRIER AIR WORKS IN FROM THE W BEHIND
THE EXITING COLD FRONT.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 524 AM EDT SUN AUG 24 2014
FOG MAY BE AN ISSUE OVER PORTIONS OF LAKE SUPERIOR THRU MON GIVEN
THE HUMID AIR MASS THAT CONTINUES TO LINGER OVER THE AREA. PASSAGE
OF A COLD FRONT MON WILL THEN WORK TO CLEAR OUT ANY FOG FROM W TO E
AS DRIER AIR FLOWS INTO THE UPPER LAKES. AHEAD OF THE COLD FRONT...E
TO SE WINDS WILL INCREASE SOME TODAY/TONIGHT. WINDS OF 15-25KT SHOULD
BE OBSERVED AT SOME OF THE HIGHER OBS PLATFORMS. IN THE WAKE OF THE
FRONT...WSW WINDS OF 15-25KT WILL DEVELOP OVER THE W HALF OF THE
LAKE ON MON. HIGH PRES WILL THEN SETTLE INTO THE UPPER LAKES LATE
TUE THRU THU...BRINGING A PERIOD OF LIGHTER WINDS MOSTLY UNDER 15KT.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...ROLFSON
LONG TERM...SRF
AVIATION...KF
MARINE...ROLFSON
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
739 AM EDT SUN AUG 24 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 524 AM EDT SUN AUG 24 2014
WATER VAPOR IMAGERY AND RUC ANALYSIS SHOW A TROF OVER THE ROCKIES
WITH DOWNSTREAM RIDGE EXTENDING N THRU THE GREAT LAKES. IN THE
TROF...A VIGOROUS SHORTWAVE WAS LIFTING THRU WY INTO ERN MT/FAR WRN
DAKOTAS. AHEAD OF THIS MAIN FEATURE...ANOTHER SHORTWAVE WAS LIFTING
THRU THE ERN DAKOTAS INTO MANITOBA. SHRA/TSRA HAVE BEEN LINED UP
WITH THIS WAVE ACROSS THE ERN DAKOTAS/WRN MN. LOW-LEVEL JET AHEAD OF
FEATURE HAS ALSO GENERATED SHRA FARTHER E IN NE MN INTO ADJACENT NRN
ONTARIO. CLOSER TO HOME...IT HAS BEEN A QUIET NIGHT. THERE HAVE BEEN
SOME SPRINKLES AT TIMES OVER THE W HALF OF UPPER MI AND PERHAPS A
BRIEF -SHRA OVER THE FAR W...PROBABLY TIED TO ERN EDGE OF LOW-LEVEL
JET. OTHERWISE...MOSTLY CLOUDY SKIES HAVE BEEN THE RULE OVER THE W
AND PARTLY CLOUDY E.
TODAY...SCT SPRINKLES/PERHAPS A -SHRA OVER THE W WILL END THIS
MORNING AS LOW-LEVEL JET LIFTS N. OTHERWISE...LOOKS LIKE A DRY DAY
IS ON THE WAY. APPROACHING COLD FRONT TODAY WILL REMAIN WELL W OF
UPPER MI WITH THE ROUGHLY N-S ORIENTED FRONT ONLY HALFWAY ACROSS MN
BY 00Z THIS EVENING. FCST SOUNDINGS ALSO SUGGEST A CAPPED
ENVIRONMENT WITH 850MB THERMAL RIDGE NOSING INTO THE AREA. SINCE
THERE IS ESSENTIALLY NO FORCING WITH MID/UPPER RIDGE HOLDING (NO
HEIGHT FALLS)...WILL CARRY DRY WEATHER THRU THE AFTN HRS. MAY BE
ABLE TO GET A FEW MORE BREAKS IN THE CLOUDS TODAY TO BOOST TEMPS
SOME. FCST REFLECTS THIS IDEA WITH MAX TEMPS MOSTLY IN THE UPPER
70S/LWR 80S. WILL BE A LITTLE COOLER IF CLOUDS CONTINUE TO BE MORE
PERSISTENT.
AS COLD FRONT PROGRESSES EASTWARD TONIGHT...HEIGHT FALLS SPREADING
OVERTOP ABUNDANT INSTABILITY (MLCAPE OF 1500-3000J/KG) SHOULD YIELD
RAPID TSTM DEVELOPMENT ALONG FRONT THIS EVENING IN MN. HIGH RES NAM
WINDOW...NCEP WRF ARW AND NMM AS WELL AS NSSL WRF ALL LOOK QUITE
REASONABLE WITH EXPECTATIONS. THE BIG QUESTION IS HOW THE STORMS
HOLD TOGETHER WHILE MOVING E INTO UPPER MI DURING THE NORMAL
NIGHTTIME DOWNWARD MLCAPE CYCLE. ALSO IN THIS CASE...DEEP LAYER
FORCING IS WEAK WHICH MAY FURTHER HASTEN A WEAKENING TREND DURING
THE NIGHT. AT THIS POINT...THE W HAS THE BEST CHC OF SEEING
CONVECTION GIVEN ARRIVAL EARLIER IN THE NIGHT. WITH DEEP LAYER SHEAR
INCREASING TO 30-40KT...STRONG STORMS AND PERHAPS AN ISOLD SVR ARE
POSSIBLE OVER THE FAR W IF STORMS ARRIVE EARLY ENOUGH BEFORE
INSTABILITY BEGINS DIMINISHING. WILL CARRY SHRA/TSRA CHANCES
EASTWARD DURING THE NIGHT...BUT WITH A GRADUAL LOWERING OF POPS.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 354 AM EDT SUN AUG 24 2014
AFTER A VERY CLOUDY PERIOD OVER THE UPPER GREAT LAKES REGION OVER
THE LAST 7-9 DAYS...EXPECT A TRANSITION TO DRIER...COOLER AND MORE
SUNSHINE FOR THE MIDDLE OF THE WORK WEEK.
THE TRANSITION WILL BE LED BY A COLD FRONT THAT WILL BE MOVING
THROUGH THE CWA MONDAY MORNING AND EARLY AFTERNOON. THIS FRONT IS
ASSOCIATED WITH 1002MB LOW PRESSURE SYSTEM THAT WILL BE MOVING FROM
NEAR LAKE WINNIPEG ON MONDAY MORNING TO JAMES BAY ON MONDAY NIGHT.
AS THIS OCCURS...AN OCCLUDED FRONT WILL STRETCH EAST INTO NORTHERN
ONTARIO AND THEN A COLD FRONT STRETCHING SOUTH ACROSS WEST/CENTRAL
LAKE SUPERIOR AND UPPER MICHIGAN AROUND 12Z ON MONDAY. EXPECT
SHOWERS AND THUNDERSTORMS TO BE ONGOING MONDAY MORNING ALONG THE
FRONT AND SHIFTING EAST THROUGH THE MORNING AND EARLY AFTERNOON
HOURS. CURRENT FORECAST CALLS FOR THE FRONT AND ASSOCIATED
SHOWERS/THUNDERSTORMS TO BE EXITING THE EASTERN CWA TOWARDS THE LATE
AFTERNOON. WHILE THERE IS HIGH CONFIDENCE ON THE TIMING OF THE COLD
FRONT MOVING THROUGH (ALTHOUGH 00Z NAM HAS SLOWED THE FRONT
DOWN A FEW HOURS)...THE AMOUNT OF SHOWERS/THUNDERSTORMS ALONG THE
FRONT IS UNCERTAIN DUE TO SEVERAL LIMITATIONS. THESE LIMITATIONS
INCLUDE THE TIME OF DAY THE FRONT IS MOVING THROUGH...MUCH OF THE
FORCING FROM THE UPPER TROUGH AND SHORTWAVES WELL TO THE NORTHWEST
AND NEAR THE SURFACE LOW...ALONG WITH LIMITED MOISTURE AND WEAK
LAPSE RATES (AROUND 6C/KM) IN THE MID LEVELS. IN ADDITION...A NOSE
OF DRY AIR MOVING IN BETWEEN 900-700MB WILL HELP TO LIMIT ANY
SURFACE OR LOW LEVEL DEVELOPMENT. THESE FACTORS COMBINE TO KEEP POPS
ON THE LOW END OF CHANCES AS THE FRONT MOVES THROUGH AND THINK THE
BEST OPPORTUNITY FOR SHOWERS/THUNDERSTORMS WILL COME FROM ANY
ONGOING STORMS MOVING INTO THE AREA FROM THE WEST TONIGHT AND TRYING
TO HOLD TOGETHER INTO MONDAY. IF SOMETHING CAN HOLD TOGETHER OR GET
GOING AS THE FRONT MOVES INTO THE EASTERN CWA MONDAY
AFTERNOON...THERE COULD BE STRONG THUNDERSTORMS WITH INSTABILITY ON
THE INCREASE (MU/ML CAPES INCREASING TO 500-1500 J/KG) AND 0-6KM
SHEAR VALUES AROUND 35KTS (OR 25-30KTS OF EFFECTIVE BASED OFF
POTENTIAL FOR ELEVATED THUNDERSTORMS). WEST OF THE COLD FRONT ON
MONDAY...WILL SEE MUCH DRIER AIR MOVING IN AND DEWPOINTS FALLING
INTO THE 50S AND SKIES BECOMING MOSTLY SUNNY.
THE LOW LEVEL WEDGE OF DRY AIR WILL REMAIN INTO MONDAY NIGHT
(PRODUCING PARTLY CLOUDY TO MOSTLY CLEAR SKIES) BEFORE 925-700MB
WINDS TURN MORE TO THE WEST AND EVENTUALLY WEST-NORTHWEST AS A
SECONDARY FRONT/TROUGH MOVES THROUGH. THERE COULD BE SOME SHOWERS
OVER THE SOUTHEAST CWA WITH THIS SECONDARY FRONT AND CLOSER TO
LINGERING MOISTURE FROM THE FIRST FRONT. BEHIND THE SECONDARY
FRONT...MODELS ARE INDICATING AN INCREASE IN 925-850MB MOISTURE
THAT WILL LEAD TO DIURNAL CLOUD DEVELOPMENT DURING THE DAY ON
TUESDAY OVER THE NORTH HALF OF THE LAND CWA EVEN THOUGH A HIGH
PRESSURE RIDGE (FROM A HIGH IN THE EASTERN DAKOTAS) WILL NOSE EAST
OVER THE WESTERN HALF OF THE CWA. FARTHER SOUTH...WOULD EXPECT
MOSTLY SUNNY SKIES AS THE COLD FRONT LOOKS TO SLIDE FAR ENOUGH SOUTH
INTO LOWER MICHIGAN AND SOUTHERN WISCONSIN TO KEEP ANY SHOWERS TO
THE SOUTH OF THE AREA. HIGH TEMPERATURES WILL BE ABOUT 10 DEGREES
COOLER ON TUESDAY THAN MONDAY...WITH HIGHS INT HE MID 70S OVER THE
SOUTHEAST HALF AND UPPER 60S OVER THE WEST NEAR LAKE SUPERIOR.
WITH THE FLOW BECOMING ZONAL FOR THE MIDDLE OF THE UPCOMING WORK
WEEK AND THE MAIN SHORTWAVES STAYING NORTH OF THE CWA AND MOVING
ACROSS NORTHERN ONTARIO...EXPECT THE HIGH PRESSURE TO FOLLOW THE
RIDGE EASTWARD WEDNESDAY INTO THURSDAY. THIS WILL PRODUCE DRY
WEATHER AND WITH 850MB TEMPS SLIGHTLY BELOW NORMAL (AROUND
9C) EXPECT HIGHS TO BE SIMILAR WITH RESPECT TO NORMAL. WILL MENTION
THAT THE SOUTH CENTRAL CWA COULD BE BRUSHED BY A FEW WEAK WAVES
RUNNING ALONG THAT FRONT TO THE SOUTH OF THE AREA ON TUESDAY
AND AGAIN THURSDAY...BUT WOULDN/T EXPECT MORE THAN A STRAY SHOWER.
THE HIGH PRESSURE RIDGE WILL BEGIN TO SLIDE EAST ON FRIDAY WHILE AN
UPPER TROUGH SEPARATED FROM THE NORTHERN STREAM FLOW SLIDES EAST
INTO THE CENTRAL PLAINS. THIS WAVE WILL DEVELOP A WEAK SURFACE LOW
IN THE CENTRAL PLAINS AND SLIDE EAST-NORTHEAST THROUGH THE GREAT
LAKES REGION FRIDAY AFTERNOON INTO FRIDAY NIGHT. 00Z GEM
IS CONSISTENT WITH PREVIOUS RUNS AND 00Z ECMWF ON A SLOWER
ARRIVAL WITH THE UPPER TROUGH AND SURFACE LOW...WHILE THE 00Z GFS
LOOKS TO HAVE CONVECTIVE FEEDBACK ISSUES IN THE CENTRAL PLAINS ON
MONDAY/TUESDAY EVENING WHICH SPEEDS UP THE UPPER TROUGH AND
PUSHES IT THROUGH 12-24HRS EARLIER. FEEL A GENERAL CONSENSUS AND
FOCUS TOWARDS THE ECMWF (AND THE MATCHING TIMING WITH THE GEM) IS A
GOOD MIDDLE POINT RIGHT NOW AND WILL FOLLOW THAT IDEA. THIS WAVE
WILL SHIFT EAST OF THE AREA ON SATURDAY AND LEAD TO DRY WEATHER.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z MONDAY MORNING)
ISSUED AT 738 AM EDT SUN AUG 24 2014
MOIST UPSLOPE FLOW HAS BROUGHT A RETURN OF LIFR CIGS TO KCMX/KSAW.
THESE LOWER CLOUDS SHOULD SCATTER OUT WITH DAYTIME HEATING...
ALLOWING VFR CONDITIONS TO DEVELOP LATE THIS MORNING OR EARLY THIS
AFTN. DOWNSLOPE SE TO S WINDS AT KIWD SHOULD KEEP CONDITIONS VFR
THERE. COLD FRONT APPROACHING FROM THE W SHOULD SPREAD SHRA/TSRA
INTO WRN UPPER MI LATE THIS EVENING. INCLUDED A MENTION OF VCTS AT
KIWD. WITH LESS CONFIDENCE IN TSRA PERSISTING DUE TO DECREASING
INSTABILITY OVERNIGHT...DID NOT INCLUDE A MENTION OF THUNDER AT
KCMX/KSAW. UNDER UPSLOPE WINDS...KSAW SHOULD SEE A RETURN OF MVFR
CIGS TONIGHT...PERHAPS IFR LATE. OTHERWISE...CONDITIONS AT KIWD/KCMX
WILL DEPEND ON INTENSITY OF SHRA THAT OCCUR AT THOSE TERMINALS.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 524 AM EDT SUN AUG 24 2014
FOG MAY BE AN ISSUE OVER PORTIONS OF LAKE SUPERIOR THRU MON GIVEN
THE HUMID AIR MASS THAT CONTINUES TO LINGER OVER THE AREA. PASSAGE
OF A COLD FRONT MON WILL THEN WORK TO CLEAR OUT ANY FOG FROM W TO E
AS DRIER AIR FLOWS INTO THE UPPER LAKES. AHEAD OF THE COLD FRONT...E
TO SE WINDS WILL INCREASE SOME TODAY/TONIGHT. WINDS OF 15-25KT SHOULD
BE OBSERVED AT SOME OF THE HIGHER OBS PLATFORMS. IN THE WAKE OF THE
FRONT...WSW WINDS OF 15-25KT WILL DEVELOP OVER THE W HALF OF THE
LAKE ON MON. HIGH PRES WILL THEN SETTLE INTO THE UPPER LAKES LATE
TUE THRU THU...BRINGING A PERIOD OF LIGHTER WINDS MOSTLY UNDER 15KT.
&&
.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
524 AM EDT SUN AUG 24 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 524 AM EDT SUN AUG 24 2014
WATER VAPOR IMAGERY AND RUC ANALYSIS SHOW A TROF OVER THE ROCKIES
WITH DOWNSTREAM RIDGE EXTENDING N THRU THE GREAT LAKES. IN THE
TROF...A VIGOROUS SHORTWAVE WAS LIFTING THRU WY INTO ERN MT/FAR WRN
DAKOTAS. AHEAD OF THIS MAIN FEATURE...ANOTHER SHORTWAVE WAS LIFTING
THRU THE ERN DAKOTAS INTO MANITOBA. SHRA/TSRA HAVE BEEN LINED UP
WITH THIS WAVE ACROSS THE ERN DAKOTAS/WRN MN. LOW-LEVEL JET AHEAD OF
FEATURE HAS ALSO GENERATED SHRA FARTHER E IN NE MN INTO ADJACENT NRN
ONTARIO. CLOSER TO HOME...IT HAS BEEN A QUIET NIGHT. THERE HAVE BEEN
SOME SPRINKLES AT TIMES OVER THE W HALF OF UPPER MI AND PERHAPS A
BRIEF -SHRA OVER THE FAR W...PROBABLY TIED TO ERN EDGE OF LOW-LEVEL
JET. OTHERWISE...MOSTLY CLOUDY SKIES HAVE BEEN THE RULE OVER THE W
AND PARTLY CLOUDY E.
TODAY...SCT SPRINKLES/PERHAPS A -SHRA OVER THE W WILL END THIS
MORNING AS LOW-LEVEL JET LIFTS N. OTHERWISE...LOOKS LIKE A DRY DAY
IS ON THE WAY. APPROACHING COLD FRONT TODAY WILL REMAIN WELL W OF
UPPER MI WITH THE ROUGHLY N-S ORIENTED FRONT ONLY HALFWAY ACROSS MN
BY 00Z THIS EVENING. FCST SOUNDINGS ALSO SUGGEST A CAPPED
ENVIRONMENT WITH 850MB THERMAL RIDGE NOSING INTO THE AREA. SINCE
THERE IS ESSENTIALLY NO FORCING WITH MID/UPPER RIDGE HOLDING (NO
HEIGHT FALLS)...WILL CARRY DRY WEATHER THRU THE AFTN HRS. MAY BE
ABLE TO GET A FEW MORE BREAKS IN THE CLOUDS TODAY TO BOOST TEMPS
SOME. FCST REFLECTS THIS IDEA WITH MAX TEMPS MOSTLY IN THE UPPER
70S/LWR 80S. WILL BE A LITTLE COOLER IF CLOUDS CONTINUE TO BE MORE
PERSISTENT.
AS COLD FRONT PROGRESSES EASTWARD TONIGHT...HEIGHT FALLS SPREADING
OVERTOP ABUNDANT INSTABILITY (MLCAPE OF 1500-3000J/KG) SHOULD YIELD
RAPID TSTM DEVELOPMENT ALONG FRONT THIS EVENING IN MN. HIGH RES NAM
WINDOW...NCEP WRF ARW AND NMM AS WELL AS NSSL WRF ALL LOOK QUITE
REASONABLE WITH EXPECTATIONS. THE BIG QUESTION IS HOW THE STORMS
HOLD TOGETHER WHILE MOVING E INTO UPPER MI DURING THE NORMAL
NIGHTTIME DOWNWARD MLCAPE CYCLE. ALSO IN THIS CASE...DEEP LAYER
FORCING IS WEAK WHICH MAY FURTHER HASTEN A WEAKENING TREND DURING
THE NIGHT. AT THIS POINT...THE W HAS THE BEST CHC OF SEEING
CONVECTION GIVEN ARRIVAL EARLIER IN THE NIGHT. WITH DEEP LAYER SHEAR
INCREASING TO 30-40KT...STRONG STORMS AND PERHAPS AN ISOLD SVR ARE
POSSIBLE OVER THE FAR W IF STORMS ARRIVE EARLY ENOUGH BEFORE
INSTABILITY BEGINS DIMINISHING. WILL CARRY SHRA/TSRA CHANCES
EASTWARD DURING THE NIGHT...BUT WITH A GRADUAL LOWERING OF POPS.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 354 AM EDT SUN AUG 24 2014
AFTER A VERY CLOUDY PERIOD OVER THE UPPER GREAT LAKES REGION OVER
THE LAST 7-9 DAYS...EXPECT A TRANSITION TO DRIER...COOLER AND MORE
SUNSHINE FOR THE MIDDLE OF THE WORK WEEK.
THE TRANSITION WILL BE LED BY A COLD FRONT THAT WILL BE MOVING
THROUGH THE CWA MONDAY MORNING AND EARLY AFTERNOON. THIS FRONT IS
ASSOCIATED WITH 1002MB LOW PRESSURE SYSTEM THAT WILL BE MOVING FROM
NEAR LAKE WINNIPEG ON MONDAY MORNING TO JAMES BAY ON MONDAY NIGHT.
AS THIS OCCURS...AN OCCLUDED FRONT WILL STRETCH EAST INTO NORTHERN
ONTARIO AND THEN A COLD FRONT STRETCHING SOUTH ACROSS WEST/CENTRAL
LAKE SUPERIOR AND UPPER MICHIGAN AROUND 12Z ON MONDAY. EXPECT
SHOWERS AND THUNDERSTORMS TO BE ONGOING MONDAY MORNING ALONG THE
FRONT AND SHIFTING EAST THROUGH THE MORNING AND EARLY AFTERNOON
HOURS. CURRENT FORECAST CALLS FOR THE FRONT AND ASSOCIATED
SHOWERS/THUNDERSTORMS TO BE EXITING THE EASTERN CWA TOWARDS THE LATE
AFTERNOON. WHILE THERE IS HIGH CONFIDENCE ON THE TIMING OF THE COLD
FRONT MOVING THROUGH (ALTHOUGH 00Z NAM HAS SLOWED THE FRONT
DOWN A FEW HOURS)...THE AMOUNT OF SHOWERS/THUNDERSTORMS ALONG THE
FRONT IS UNCERTAIN DUE TO SEVERAL LIMITATIONS. THESE LIMITATIONS
INCLUDE THE TIME OF DAY THE FRONT IS MOVING THROUGH...MUCH OF THE
FORCING FROM THE UPPER TROUGH AND SHORTWAVES WELL TO THE NORTHWEST
AND NEAR THE SURFACE LOW...ALONG WITH LIMITED MOISTURE AND WEAK
LAPSE RATES (AROUND 6C/KM) IN THE MID LEVELS. IN ADDITION...A NOSE
OF DRY AIR MOVING IN BETWEEN 900-700MB WILL HELP TO LIMIT ANY
SURFACE OR LOW LEVEL DEVELOPMENT. THESE FACTORS COMBINE TO KEEP POPS
ON THE LOW END OF CHANCES AS THE FRONT MOVES THROUGH AND THINK THE
BEST OPPORTUNITY FOR SHOWERS/THUNDERSTORMS WILL COME FROM ANY
ONGOING STORMS MOVING INTO THE AREA FROM THE WEST TONIGHT AND TRYING
TO HOLD TOGETHER INTO MONDAY. IF SOMETHING CAN HOLD TOGETHER OR GET
GOING AS THE FRONT MOVES INTO THE EASTERN CWA MONDAY
AFTERNOON...THERE COULD BE STRONG THUNDERSTORMS WITH INSTABILITY ON
THE INCREASE (MU/ML CAPES INCREASING TO 500-1500 J/KG) AND 0-6KM
SHEAR VALUES AROUND 35KTS (OR 25-30KTS OF EFFECTIVE BASED OFF
POTENTIAL FOR ELEVATED THUNDERSTORMS). WEST OF THE COLD FRONT ON
MONDAY...WILL SEE MUCH DRIER AIR MOVING IN AND DEWPOINTS FALLING
INTO THE 50S AND SKIES BECOMING MOSTLY SUNNY.
THE LOW LEVEL WEDGE OF DRY AIR WILL REMAIN INTO MONDAY NIGHT
(PRODUCING PARTLY CLOUDY TO MOSTLY CLEAR SKIES) BEFORE 925-700MB
WINDS TURN MORE TO THE WEST AND EVENTUALLY WEST-NORTHWEST AS A
SECONDARY FRONT/TROUGH MOVES THROUGH. THERE COULD BE SOME SHOWERS
OVER THE SOUTHEAST CWA WITH THIS SECONDARY FRONT AND CLOSER TO
LINGERING MOISTURE FROM THE FIRST FRONT. BEHIND THE SECONDARY
FRONT...MODELS ARE INDICATING AN INCREASE IN 925-850MB MOISTURE
THAT WILL LEAD TO DIURNAL CLOUD DEVELOPMENT DURING THE DAY ON
TUESDAY OVER THE NORTH HALF OF THE LAND CWA EVEN THOUGH A HIGH
PRESSURE RIDGE (FROM A HIGH IN THE EASTERN DAKOTAS) WILL NOSE EAST
OVER THE WESTERN HALF OF THE CWA. FARTHER SOUTH...WOULD EXPECT
MOSTLY SUNNY SKIES AS THE COLD FRONT LOOKS TO SLIDE FAR ENOUGH SOUTH
INTO LOWER MICHIGAN AND SOUTHERN WISCONSIN TO KEEP ANY SHOWERS TO
THE SOUTH OF THE AREA. HIGH TEMPERATURES WILL BE ABOUT 10 DEGREES
COOLER ON TUESDAY THAN MONDAY...WITH HIGHS INT HE MID 70S OVER THE
SOUTHEAST HALF AND UPPER 60S OVER THE WEST NEAR LAKE SUPERIOR.
WITH THE FLOW BECOMING ZONAL FOR THE MIDDLE OF THE UPCOMING WORK
WEEK AND THE MAIN SHORTWAVES STAYING NORTH OF THE CWA AND MOVING
ACROSS NORTHERN ONTARIO...EXPECT THE HIGH PRESSURE TO FOLLOW THE
RIDGE EASTWARD WEDNESDAY INTO THURSDAY. THIS WILL PRODUCE DRY
WEATHER AND WITH 850MB TEMPS SLIGHTLY BELOW NORMAL (AROUND
9C) EXPECT HIGHS TO BE SIMILAR WITH RESPECT TO NORMAL. WILL MENTION
THAT THE SOUTH CENTRAL CWA COULD BE BRUSHED BY A FEW WEAK WAVES
RUNNING ALONG THAT FRONT TO THE SOUTH OF THE AREA ON TUESDAY
AND AGAIN THURSDAY...BUT WOULDN/T EXPECT MORE THAN A STRAY SHOWER.
THE HIGH PRESSURE RIDGE WILL BEGIN TO SLIDE EAST ON FRIDAY WHILE AN
UPPER TROUGH SEPARATED FROM THE NORTHERN STREAM FLOW SLIDES EAST
INTO THE CENTRAL PLAINS. THIS WAVE WILL DEVELOP A WEAK SURFACE LOW
IN THE CENTRAL PLAINS AND SLIDE EAST-NORTHEAST THROUGH THE GREAT
LAKES REGION FRIDAY AFTERNOON INTO FRIDAY NIGHT. 00Z GEM
IS CONSISTENT WITH PREVIOUS RUNS AND 00Z ECMWF ON A SLOWER
ARRIVAL WITH THE UPPER TROUGH AND SURFACE LOW...WHILE THE 00Z GFS
LOOKS TO HAVE CONVECTIVE FEEDBACK ISSUES IN THE CENTRAL PLAINS ON
MONDAY/TUESDAY EVENING WHICH SPEEDS UP THE UPPER TROUGH AND
PUSHES IT THROUGH 12-24HRS EARLIER. FEEL A GENERAL CONSENSUS AND
FOCUS TOWARDS THE ECMWF (AND THE MATCHING TIMING WITH THE GEM) IS A
GOOD MIDDLE POINT RIGHT NOW AND WILL FOLLOW THAT IDEA. THIS WAVE
WILL SHIFT EAST OF THE AREA ON SATURDAY AND LEAD TO DRY WEATHER.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT)
ISSUED AT 140 AM EDT SUN AUG 24 2014
A LOT OF HIGH CLOUDS AROUND AND THIS MAY IMPACT IF LOW CLOUDS AND
FOG CAN DEVELOP. GIVEN SE WINDS IN LOW-LEVELS...BEST CHANCE OF LIFR
OR EVEN VLIFR CONDITIONS IS AT KSAW WITH UPSLOPE FLOW LATE IN THE
NIGHT. CHANCES WILL ONLY INCREASE IF HIGH CLOUDS CLEAR OUT MORE THAN
EXPECTED. TRIMMED BACK ON THE CHANCES AT KIWD AND KCMX THOUGH AS THE
LOW-LEVEL WINDS ARE NOT AS FAVORABLE FOR PERSISTENT FOG AT EITHER
SITE...ESPECIALLY AS THICKER HIGHER CLOUDS LIMIT RADIATIONAL FOG
PROCESSES. EXPECT IMPROVEMENT TODAY WITH CIGS LIFTING TO HIGHER MVFR OR
EVEN LOWER VFR AT ALL THE TAF SITES DUE TO DAYTIME MIXING. INVERSION
STUCK AROUND 3KFT WILL LIKELY PROHIBIT CLOUDS FROM CLEARING OUT
COMPELTELY THOUGH.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 524 AM EDT SUN AUG 24 2014
FOG MAY BE AN ISSUE OVER PORTIONS OF LAKE SUPERIOR THRU MON GIVEN
THE HUMID AIR MASS THAT CONTINUES TO LINGER OVER THE AREA. PASSAGE
OF A COLD FRONT MON WILL THEN WORK TO CLEAR OUT ANY FOG FROM W TO E
AS DRIER AIR FLOWS INTO THE UPPER LAKES. AHEAD OF THE COLD FRONT...E
TO SE WINDS WILL INCREASE SOME TODAY/TONIGHT. WINDS OF 15-25KT SHOULD
BE OBSERVED AT SOME OF THE HIGHER OBS PLATFORMS. IN THE WAKE OF THE
FRONT...WSW WINDS OF 15-25KT WILL DEVELOP OVER THE W HALF OF THE
LAKE ON MON. HIGH PRES WILL THEN SETTLE INTO THE UPPER LAKES LATE
TUE THRU THU...BRINGING A PERIOD OF LIGHTER WINDS MOSTLY UNDER 15KT.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...ROLFSON
LONG TERM...SRF
AVIATION...JLA
MARINE...ROLFSON
AREA FORECAST DISCUSSION
NWS HASTINGS NE
1204 AM CDT SUN AUG 24 2014
.SHORT TERM...(THIS EVENING THROUGH SUNDAY)
ISSUED AT 345 PM CDT SAT AUG 23 2014
STUBBORN LOWER CLOUDS STILL HANGING ON ACROSS NORTHWEST PART OF
THE FORECAST AREA. SULTRY AIRMASS TODAY AS WELL...WITH DEWPOINTS
AROUND 70 SEVERAL LOCATIONS. MOST MODELS TRY TO PUMP IN SOME DRIER
AIR FROM THE SOUTH THROUGH THIS EVENING...WITH THE HRRR MOST
AGGRESSIVE. THAT COULD PROVIDE A LITTLE HUMIDITY RELIEF TO SOME
SPOTS IN THE SOUTHERN/SOUTHEAST FORECAST AREA. AS WE WORK INTO
TONIGHT...THE PROSPECT OF THUNDERSTORMS IS MUCH MUCH LOWER...BUT
NOT NIL. A DECENT LOW LEVEL JET WILL DEVELOP AND THAT COULD SUSTAIN
HIGH PLAINS CONVECTION...BUT ALSO SPARK A FEW OTHER ISOLATED SHOWERS
AND STORMS. OVERALL COVERAGE SHOULD BE ISOLATED...BUT CAN NOT
TOTALLY RULE IT OUT.
SUNDAY SHOULD START WITH LINGERING MID/HIGH CLOUDS FROM LEFTOVER
SHOWERS AND THUNDERSTORMS IN PARTS OF THE PLAINS. THESE MAY HOLD
OVER INTO THE POST SUNRISE HOURS OVER NORTHERN PARTS OF THE
FORECAST NEAR A FRONTAL BOUNDARY...BUT COVERAGE WILL BE SPARSE
AND 20 PERCENT CHANCES REPRESENT RAIN RISK WELL.
A WEAK FRONTAL BOUNDARY WILL ATTEMPT TO MOVE ACROSS THE FORECAST
AREA SUNDAY. MODELS SEEM A BIT AGGRESSIVE...BUT SOMETIMES THAT DOES
WORK OUT. EXPECT A SHIFTING WIND...AND THEN A DYING WIND AS THE
FORECAST IS LEFT TO FLOUNDER IN THE SURFACE SURFACE WITH THE FRONT
WEAKENING WITH TIME. THE WEAK NATURE OF THE FRONT AND SOME WARM MID
LEVEL TEMPERATURES WILL PROBABLY KEEP ANY DEVELOPMENT OF
THUNDERSTORMS NEAR OR ALONG THE FRONT VERY SPARSE AND TOWARD EVENING
AT THE EARLIEST. HAVE KEPT SIMILAR IDEA OF LOWER DEWPOINTS BEHIND
THE FRONTAL PASSAGE...BUT HAVE SOME DOUBT PLACES LIKE GRAND ISLAND
AND HASTINGS COULD DROP TO A SUB-60 DEWPOINT LATE SUNDAY AFTERNOON.
THAT WOULD BE NICE BUT WE WILL SEE.
.LONG TERM...(SUNDAY NIGHT THROUGH SATURDAY)
ISSUED AT 345 PM CDT SAT AUG 23 2014
UNSETTLED WEATHER CONDITIONS WILL CONTINUE THROUGH MUCH OF THE
EXTENDED PERIODS AS THE LOCAL AREA WILL REMAIN UNDER THE INFLUENCE
OF A LARGE TROUGH OF LOW PRESSURE ACROSS THE INTERMOUNTAIN WEST
WITH WEST TO SOUTHWESTERLY FLOW PERSISTING ALOFT.
EXPECT THE MAIN UPPER LEVEL LOW ACROSS THE DAKOTAS SUNDAY EVENING
TO LIFT NORTHEAST...WITH A SECONDARY FRONTAL BOUNDARY PUSHING
ACROSS THE LOCAL AREA. WHILE THIS FRONTAL BOUNDARY MAY PROVIDE THE
TRIGGER FOR SOME ELEVATED CONVECTION ACROSS THE SOUTHEASTERN
PORTIONS OF THE LOCAL AREA EARLY IN THE EVENING...EXPECT THE
BETTER CHANCES TO SPREAD FROM WEST TO EAST AFTER MIDNIGHT AS A
TRAILING MID LEVEL DISTURBANCE MOVES ACROSS THE LOCAL AREA FROM
THE HIGH PLAINS AND A WEAK LOW LEVEL JET FOCUSES ITSELF ACROSS
NORTH CENTRAL KANSAS.
AS THIS FIRST UPPER LEVEL LOW TRACKS WELL INTO CANADA...EXPECT A
SECOND UPPER LEVEL LOW TO SLIDE FROM THE PACIFIC NORTHWEST AND
INTO THE INTERMOUNTAIN WEST BY MONDAY...MAINTAINING SOUTHWESTERLY
ALOFT ACROSS THE REGION. WHILE CHANCES FOR PRECIPITATION WILL
DECREASE SOME DURING THE DAY ON MONDAY...KEPT SOME SMALL POPS IN
THE FORECAST AS THE OLD FRONTAL BOUNDARY WILL BE MEANDERING
ACROSS THE REGION. THAT SAID...THE BETTER SHOT FOR MORE
WIDESPREAD CONVECTION WILL BE MONDAY NIGHT...AS YET ANOTHER UPPER
LEVEL DISTURBANCE IN SOUTHWESTERLY FLOW TRAVERSES THE REGION IN
CONCERT WITH AN INCREASING LOW LEVEL JET AIMED ACROSS SOUTH
CENTRAL NEBRASKA. WITH SEVERAL THOUSAND JOULES OF CAPE IN PLACE
AND MODEST SHEAR VALUES FORECAST...EXPECT THE POTENTIAL FOR AN
ACTIVE NIGHT ACROSS THE LOCAL AREA...ESPECIALLY FROM THE STATE
LINE NORTH. DUE TO SOME DISCREPANCIES IN MODEL DATA...
HOWEVER...ONLY WENT AHEAD AND ADVERTISED LIMITED SEVERE POTENTIAL
FOR MONDAY NIGHT IN THE HWO.
OTHERWISE...THUNDERSTORM ACTIVITY TUESDAY SHOULD ONCE AGAIN BE
FOCUSED NEAR THE LOW LEVEL JET DURING THE EVENING AND OVERNIGHT
HOURS...WITH A COLD FRONT EXPECTED TO BRING YET ANOTHER CHANCE
FOR THUNDERSTORMS ACROSS THE LOCAL AREA WEDNESDAY AND WEDNESDAY
NIGHT. WHILE A CHANCE FOR PRECIPITATION IS IN THE FORECAST SUNDAY
THROUGH THURSDAY...AT THIS TIME THE BEST POTENTIAL FOR ANY SEVERE
WEATHER APPEARS TO BE PRIMARILY DURING THE EVENING AND OVERNIGHT
HOURS MONDAY THROUGH WEDNESDAY...WITH A COOLER...DRIER...AND MORE
STABLE AIRMASS EXPECTED TO SETTLE IN ACROSS THE REGION TO END THE
WEEK.
HYDROLOGY WISE...DUE TO THE RECENT RAINFALL AND SATURATED SOILS
ACROSS MUCH OF THE LOCAL AREA...CONTINUED WITH THE MENTION OF
LOCALIZED FLOODING THE HWO IN THIS UNSETTLED PATTERN.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT)
ISSUED AT 1159 PM CDT SAT AUG 23 2014
SCATTERED THUNDERSTORMS DEVELOPED TONIGHT IN WAA AHEAD OF AN
APPROACHING COLD FRONTAL BOUNDARY AND AS THE LLVL JET HAS
STRENGTHENED. IT WILL BE HIT OR MISS ON WHETHER THE CONVECTION
WILL AFFECT THE TERMINALS WITH THE BETTER CHCS NORTH OF KEAR AND
KGRI. THERE WILL BE A PERIOD OF LLVL WIND SHEAR UNTIL THE FRONTAL
BOUNDARY ARRIVES. MAINLY DRY CONDITIONS ARE FORECAST DURING THE
DAYTIME HOURS SUNDAY.
&&
.GID WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
KS...NONE.
&&
$$
SHORT TERM...MORITZ
LONG TERM...ROSSI
AVIATION...FAY
AREA FORECAST DISCUSSION...UPDATED
NWS NORTH PLATTE NE
1133 PM CDT SAT AUG 23 2014
.SYNOPSIS...
ISSUED AT 313 PM CDT SAT AUG 23 2014
H5 ANALYSIS FROM THIS MORNING HAS RIDGING ACROSS THE
MISSISSIPPI VALLEY FROM THE GULF COAST NWD INTO THE WESTERN GREAT
LAKES. FURTHER EAST...DECENT SHORTWAVES WERE NOTED OVER LAKE ONTARIO
AND NOVA SCOTIA. FURTHER WEST...A TANDEM OF SHORTWAVES WERE LOCATED OVER
THE INTERMOUNTAIN WEST. THE FIRST OVER WESTERN COLORADO AND A SECOND
OVER EASTERN IDAHO...WHILE ANOTHER SHORTWAVE WAS UPSTREAM OVER THE
ALASKA PANHANDLE. WV IMAGERY AS OF 1 PM CDT...INDICATED SHORTWAVE
ENERGY IN ASSOCIATION WITH THE WAVE OVER WESTERN COLORADO HAD BEGUN
TO EMERGE ACROSS CENTRAL COLORADO AND HAS LED TO INCREASING
CLOUDINESS ALONG THE FRONT RANGE OF COLORADO. OVER THE NEXT COUPLE
OF HRS...SHRAS AND TSRAS ARE EXPECTED TO DEVELOP ON THE LEE SIDE OF
THE ROCKIES INVOF THE FRONT RANGES OF COLORADO AND WYOMING. FURTHER
WEST...A CLOSED LOW REMAINS IN PLACE OVER EASTERN IDAHO ATTM WITH A
BROAD AREA OF CLOUDS AND SHOWERS ACROSS MONTANA...NORTH DAKOTA AND
NORTHERN SOUTH DAKOTA. ACROSS WESTERN AND NORTH CENTRAL
NEBRASKA...ABUNDANT CLOUDINESS WAS PRESENT OVER MOST OF THE AREA
WITH THE EXCEPTION OF FAR SWRN NEBRASKA AND THE EASTERN NEBRASKA
PANHANDLE WHERE CLOUDS HAVE SCATTERED OUT OVER THE PAST 1 TO 2
HOURS. AT THE SURFACE...A TANDEM OF LOW PRESSURE CENTERS WERE
PRESENT ACROSS SERN WYOMING AND A SECOND OVER SOUTH CENTRAL SD. A
WARM FRONT EXTENDED FROM SERN WYOMING INTO EASTERN SOUTH
DAKOTA...WHILE A COLD FRONT EXTENDED SSWD INTO THE CENTRAL ROCKIES.
UNDER PARTLY TO MOSTLY CLOUDY SKIES...TEMPERATURES AS OF 3 PM
CDT...RANGED FROM 72 AT AINSWORTH...TO 82 AT BROKEN BOW.
&&
.SHORT TERM...(THIS EVENING THROUGH SUNDAY)
ISSUED AT 313 PM CDT SAT AUG 23 2014
MODELS REMAIN IN GOOD AGREEMENT
WITH THE PROJECTIONS OF A PV ANOMALY LIFTING NORTHEAST FROM FAR
SOUTHWESTERN WYOMING TOWARD THE NORTHERN PLAINS THIS EVENING AND
OVERNIGHT. RECENT OBSERVATIONS INDICATE THAT THE LOW STRATUS IS
DISSIPATING EARLY THIS AFTERNOON...LEADING TO THE EVENTUAL
DESTABILIZATION OF THE LOWER TROPOSPHERE. AS HEIGHTS FALL WITH THE
APPROACH OF THE PV MAX/ATTENDANT COLD FRONT...STORMS ARE ANTICIPATED
TO FORM INVOF OF THE HIGH PLAINS SURFACE LOW/FRONTAL BOUNDARY AND
POSSIBLY DRIFT EAST ACROSS THE SANDHILLS REGION OF NEB OVERNIGHT.
THE LATEST PROJECTIONS FROM THE RAP AND HRRR SHOWS THAT DESPITE THE
MORNING CLOUDS...LOW TO MID LEVEL LAPSE RATES HAVE INCREASED
SOME...YIELDING A WEAKLY UNSTABLE ATMOSPHERE ACROSS WESTERN PORTIONS
OF THE CWA /CONTINUED CLEARING WILL ALLOW FOR FURTHER
DESTABILIZATION/. THE PROJECTED INSTABILITY /UPWARDS TO 1000 J/KG
ML CAPE/ COMBINED WITH 0-6KM BULK SHEAR OF 30KTS OR SO WILL PROMOTE
THE POSSIBILITY OF STRONG TO LOW END SEVERE STORMS THIS EVENING AND
OVERNIGHT. ANOTHER AREA TO WATCH FOR SEVERE STORMS WILL BE ACROSS
NORTH CENTRAL NEBRASKA LATE THIS AFTERNOON AS A SECONDARY WARM FRONT
LIFTS NORTH TOWARD THE SOUTHEAST SOUTH DAKOTA. ABUNDANT INSTABILITY
AND SUFFICIENT SHEAR WOULD PROMOTE RAPID STORM DEVELOPMENT CAPABLE
OF LARGE HAIL AND DAMAGING WIND GUSTS.
THE HEAVY RAIN THREAT WILL BE NOTICEABLY LESS TONIGHT AS BUFR
SOUNDINGS REVEAL A MUCH LESSER INFLUENCE FROM WARM RAIN
PROCESSES...BUT WITH PWATS AT OR SLIGHTLY ABOVE AVERAGE...BRIEF
HEAVY RAINFALL IS STILL POSSIBLE.
THE COLD FRONT CLEARS THE CWA EARLY ON SUNDAY WITH RAIN CHANCES
POSSIBLY LINGERING ACROSS OUR FAR EAST THROUGH 15Z...OTHERWISE A
SLIGHTLY COOLER AIRMASS IS ANTICIPATED WITH HIGHS RANGING FROM THE
MID 70S ACROSS OUR FAR NORTHWEST...TO LOW TO MID 80S SOUTH OF THE
INTERSTATE 80 CORRIDOR. WITH MOISTURE LACKING AND A STABLE AIRMASS
ANTICIPATED SUNDAY AFTERNOON...STORM CHANCES SHOULD BE KEPT AT BAY
UNTIL AT LEAST 00Z MONDAY.
.LONG TERM...(SUNDAY NIGHT THROUGH SATURDAY)
ISSUED AT 331 PM CDT SAT AUG 23 2014
SUNDAY NIGHT THROUGH TUESDAY...THE MAIN FORECASTING
CHALLENGE CONTINUES TO BE PRECIPITATION CHANCES AND THE THREAT FOR
HEAVY RAIN AS A TROUGH AND SEMI STATIONARY FRONTAL BOUNDARY PERSISTS
ACROSS THE CENTRAL ROCKIES AND PLAINS DURING THE PERIOD. FOR SUNDAY
NIGHT...AFTER RELATIVELY QUIET WEATHER CONDS SUNDAY...MID LEVEL WAA
WILL INCREASE ALONG THE FRONT RANGE DURING THE
EVENING...TRANSITIONING EAST ACROSS THE CENTRAL PLAINS OVERNIGHT
SUNDAY NIGHT INTO EARLY MONDAY. AT THE SAME TIME...A NICE H250 JET
STREAK WILL LIFT ACROSS NWRN NEBRASKA INTO SOUTH DAKOTA PLACING
WESTERN AND NORTH CENTRAL NEBRASKA IN THE RIGHT REAR QUAD OF THIS
FEATURE. ENHANCED LIFT ACROSS THE FORECAST AREA...WILL LEAD TO A
SHARP INCREASE IN THE THREAT OF PCPN SUNDAY NIGHT INTO MONDAY. IN
THE LOWER LEVELS...A FRONTAL BOUNDARY WILL BE ANCHORED ACROSS SRN
NEBRASKA SUNDAY NIGHT WITH THE NOSE OF A H85 LOW LEVEL JET
POSITIONED ACROSS SWRN NEBRASKA. INHERITED FCST HAD THE HIGHEST POPS
ACROSS SRN PORTIONS OF THE FORECAST AREA SUNDAY NIGHT INTO MONDAY
MORNING AND APPEARS ON TRACK ATTM. PRECIPITATION CHANCES WILL
DECREASE SOMEWHAT MONDAY AS MID LEVEL FORCING PUSHES EAST INTO THE
MID MISSOURI VALLEY. BY MONDAY NIGHT...ANOTHER STRONG UPPER LEVEL
DISTURBANCE WILL PUSH ACROSS THE CENTRAL PLAINS...LEADING TO
INCREASED CHANCES FOR RAIN MONDAY NIGHT...AS WELL AS TUESDAY NIGHT. LOW
LEVEL EASTERLY WINDS AND ABUNDANT MID AND UPPER LEVEL MOISTURE
TRANSPORT FROM THE SOUTHWEST IN ASSOCIATION WITH HURRICANE MARIE
COULD LEAD TO HEAVY RAIN ACROSS THE CENTRAL PLAINS BEGINNING MONDAY
NIGHT AND POSSIBLY PERSISTING INTO TUESDAY NIGHT. FURTHER SUPPORT
FOR HEAVY RAIN IS EVIDENT IN FCST PWATS RANGING FROM 1.5 TO 2.0
INCHES MONDAY NIGHT THROUGH TUESDAY NIGHT.
WEDNESDAY THROUGH SATURDAY...LINGERING PCPN CHANCES ARE THE MAIN
FORECAST CHALLENGE IN THE LONG RANGE PERIODS. BY WEDNESDAY INTO
THURSDAY...THE PERSISTENT UPPER LEVEL TROUGH ACROSS THE
ROCKIES...WILL CROSS THE CENTRAL PLAINS INTO THE MISSISSIPPI VALLEY.
THE LATEST GFS SOLN IS 24 HRS FASTER COMPARED TO THE ECMWF IN
LIFTING THIS FEATURE EAST OF THE AREA. THE GFS IS DRY AFTER WEDS
WITH THE TROUGH OVER MISSOURI VALLEY BY 12Z THURSDAY...WHILE THE
ECMWF HAS THIS FEATURE OVER THE SAME AREA BY 12Z FRIDAY. INHERITED
FCST WAS DRY WEDS NIGHT AND INTRODUCED POPS FOR THIS PERIOD AS BOTH
MODELS HAVE TRENDED SLOWER. WILL HOLD OFF ON INTRODUCING POPS FOR
THURSDAY FOR NOW AND WAIT FOR THE MODELS TO COME INTO BETTER
AGREEMENT. AFTER UNSEASONABLY COOL HIGHS IN THE 70S FOR WEDNESDAY
AND THURSDAY...HIGHS WILL REBOUND BACK INTO THE 80S FOR THURSDAY AND
FRIDAY.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT)
ISSUED AT 1131 PM CDT SAT AUG 23 2014
TSTM ACTIVITY UNDERWAY SHOULD EXIT THE FCST AREA TO THE EAST 12Z-15Z
SUNDAY MORNING WITH VFR THEREAFTER THROUGH 00Z. THE NEXT AREA OF
TSTMS MAY MOVE INTO SWRN NEB SUNDAY EVENING 03Z-06Z.
&&
.LBF WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...CLB
SHORT TERM...JACOBS
LONG TERM...CLB
AVIATION...CDC
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
1022 PM EDT MON AUG 25 2014
.SYNOPSIS...
A WARM RIDGE OF HIGH PRESSURE WILL EXPAND EASTWARD ACROSS THE AREA
THROUGH LATE WEEK. HURRICANE CRISTOBAL WILL MOVE NORTHEAST...PASSING
WELL 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 1030 PM MONDAY...QUITE A FEW MORE CLOUDS HAVE HUNG ON INLAND
THAN WAS ANTICIPATED. THE 00Z CHS SOUNDING INDICATED MOISTURE
EXTENDS UP TO AROUND 6500 FEET BEFORE SUBSTANTIAL DRYING ALOFT. UP
THE COAST AT MHX THERE WAS LESS MOISTURE PRESENT OVERALL EVEN THOUGH
SUBSTANTIAL DRYING DIDN`T BEGIN UNTIL NEAR 700 MB. ADJUSTMENTS HAVE
BEEN MADE MAINLY TO SKY COVER...OTHERWISE THE PREVIOUS FORECAST
LOOKS REASONABLE. PREVIOUS DISCUSSION FROM 730 PM FOLLOWS...
RADAR SHOWS SCATTERED SHOWERS ACROSS THE COASTAL WATERS BRUSHING THE
COAST NEAR CAPE FEAR. MOTION IS TOWARD THE SOUTHWEST AT 20 MPH. THE
SOUTHERN HALF OF THE GRAND STRAND DOWN THROUGH GEORGETOWN IS IN THE
PATH OF THESE SCATTERED SHOWERS OVER THE NEXT FEW HOURS...WITH
FORECAST POPS GENERALLY IN THE 20-40 PERCENT RANGE. AS INLAND
TEMPERATURES COOL AND A POCKET OF MUCH DRIER AIR AT 850 MB ARRIVES
FROM THE NORTHEAST...LOOK FOR SKIES TO BECOME CLEAR ACROSS MOST OF
THE AREA OVERNIGHT. A STABILIZING BOUNDARY LAYER ALSO MEANS THE
MARINE SHOWERS SHOULD HAVE LITTLE SUCCESS PUSHING INLAND ACROSS
SOUTH CAROLINA.
ASIDE FROM TWEAKS TO EARLY EVENING SHOWER CHANCES...WINDS...AND SKY
COVER...THE PREVIOUS FORECAST IS ESSENTIALLY UNCHANGED. PREVIOUS
DISCUSSION FROM 300 PM FOLLOWS...
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 /00Z TUESDAY THROUGH SATURDAY/...
AS OF 00Z...EXPECT VFR TO PREVAIL THROUGH THE VALID TAF PERIOD AS
RIDGE OF HIGH PRESSURE CONTINUES TO BUILD INTO THE AREA.
LATEST RADAR IMAGERY DEPICTS ISOLATED LIGHT SHOWERS MOVING
SOUTHWEST...MAINLY OFFSHORE. COULD NOT RULE OUT A SHOWER OR TWO TO
MOVE OVER ONE OF THE COASTAL SITES...BUT DO NOT ANTICIPATE THEY WILL
CREATE ANY RESTRICTIONS AND WILL BE SHORT-LIVED. OVERALL...VFR
PREVAILS WITH FEW/SCT/BKN LOW TO MID CLOUDS PUSHING ACROSS THE AREA.
EXPECT THESE TO DECREASE IN COVERAGE OVERNIGHT WITH NORTHEAST WINDS
TO PREVAIL...AROUND 5 TO 10 KTS. GIVEN INCREASED BOUNDARY LAYER
WINDS...DO NOT ANTICIPATE ANY FOG DEVELOPMENT..ESPECIALLY ALONG THE
COAST. HOWEVER...WOULD NOT ENTIRELY RULE OUT LIGHT...PATCHY FOG
INLAND. ON TUESDAY...VFR WILL PREVAIL WITH NORTHEAST WINDS 10 TO 12
KTS...WITH SLIGHTLY HIGHER GUSTS...ESPECIALLY IN THE LATE
MORNING/EARLY AFTERNOON HOURS.
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 1030 PM MONDAY...NO SIGNIFICANT CHANGES NEEDED WITH THIS LATE
EVENING UPDATE. PREVIOUS DISCUSSION FROM 730 PM FOLLOWS...
BASED ON BUOY AND COASTAL OBSERVATIONS I HAVE BUMPED WINDS UP BY A
FEW KNOTS FOR AREAS AWAY FROM THE PROTECTED PORTION OF THE COAST
BETWEEN BALD HEAD ISLAND AND NORTH MYRTLE BEACH. OTHERWISE NO
CHANGES. PREVIOUS DISCUSSION FROM 300 PM FOLLOWS...
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...HIGH RIP CURRENT RISK FROM 7 AM TUESDAY THROUGH TUESDAY
EVENING FOR GEORGETOWN COUNTY.
NC...COASTAL FLOOD ADVISORY UNTIL MIDNIGHT FOR INLAND NEW HANOVER
COUNTY.
HIGH RIP CURRENT RISK FROM 7 AM TUESDAY THROUGH TUESDAY
EVENING FOR COASTAL PENDER AND COASTAL NEW HANOVER COUNTIES.
MARINE...SMALL CRAFT ADVISORY UNTIL 8 PM EDT TUESDAY FOR
AMZ250-252-254-256.
&&
$$
NEAR TERM...JDW/TRA
SHORT TERM...RJD
LONG TERM...SHK
AVIATION...SGL
TIDES/COASTAL FLOODING...JDW
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
735 PM EDT MON AUG 25 2014
.SYNOPSIS...
A WARM RIDGE OF HIGH PRESSURE WILL EXPAND EASTWARD ACROSS THE AREA
THROUGH LATE WEEK. TROPICAL STORM CRISTOBAL WILL MOVE
NORTHEAST...PASSING WELL 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 730 PM MONDAY...RADAR SHOWS SCATTERED SHOWERS ACROSS THE
COASTAL WATERS BRUSHING THE COAST NEAR CAPE FEAR. MOTION IS TOWARD
THE SOUTHWEST AT 20 MPH. THE SOUTHERN HALF OF THE GRAND STRAND DOWN
THROUGH GEORGETOWN IS IN THE PATH OF THESE SCATTERED SHOWERS OVER
THE NEXT FEW HOURS...WITH FORECAST POPS GENERALLY IN THE 20-40
PERCENT RANGE. AS INLAND TEMPERATURES COOL AND A POCKET OF MUCH
DRIER AIR AT 850 MB ARRIVES FROM THE NORTHEAST...LOOK FOR SKIES TO
BECOME CLEAR ACROSS MOST OF THE AREA OVERNIGHT. A STABILIZING
BOUNDARY LAYER ALSO MEANS THE MARINE SHOWERS SHOULD HAVE LITTLE
SUCCESS PUSHING INLAND ACROSS SOUTH CAROLINA.
ASIDE FROM TWEAKS TO EARLY EVENING SHOWER CHANCES...WINDS...AND SKY
COVER...THE PREVIOUS FORECAST IS ESSENTIALLY UNCHANGED. PREVIOUS
DISCUSSION FROM 300 PM FOLLOWS...
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 /00Z TUESDAY THROUGH SATURDAY/...
AS OF 00Z...EXPECT VFR TO PREVAIL THROUGH THE VALID TAF PERIOD AS
RIDGE OF HIGH PRESSURE CONTINUES TO BUILD INTO THE AREA.
LATEST RADAR IMAGERY DEPICTS ISOLATED LIGHT SHOWERS MOVING
SOUTHWEST...MAINLY OFFSHORE. COULD NOT RULE OUT A SHOWER OR TWO TO
MOVE OVER ONE OF THE COASTAL SITES...BUT DO NOT ANTICIPATE THEY WILL
CREATE ANY RESTRICTIONS AND WILL BE SHORT-LIVED. OVERALL...VFR
PREVAILS WITH FEW/SCT/BKN LOW TO MID CLOUDS PUSHING ACROSS THE AREA.
EXPECT THESE TO DECREASE IN COVERAGE OVERNIGHT WITH NORTHEAST WINDS
TO PREVAIL...AROUND 5 TO 10 KTS. GIVEN INCREASED BOUNDARY LAYER
WINDS...DO NOT ANTICIPATE ANY FOG DEVELOPMENT..ESPECIALLY ALONG THE
COAST. HOWEVER...WOULD NOT ENTIRELY RULE OUT LIGHT...PATCHY FOG
INLAND. ON TUESDAY...VFR WILL PREVAIL WITH NORTHEAST WINDS 10 TO 12
KTS...WITH SLIGHTLY HIGHER GUSTS...ESPECIALLY IN THE LATE
MORNING/EARLY AFTERNOON HOURS.
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 730 PM MONDAY...BASED ON BUOY AND COASTAL OBSERVATIONS I HAVE
BUMPED WINDS UP BY A FEW KNOTS FOR AREAS AWAY FROM THE PROTECTED
PORTION OF THE COAST BETWEEN BALD HEAD ISLAND AND NORTH MYRTLE
BEACH. OTHERWISE NO CHANGES. PREVIOUS DISCUSSION FROM 300 PM
FOLLOWS...
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.
HIGH RIP CURRENT RISK FROM 7 AM TUESDAY THROUGH TUESDAY
EVENING FOR GEORGETOWN COUNTY.
NC...COASTAL FLOOD ADVISORY FROM 7 PM TO 10 PM EDT THIS EVENING FOR
NCZ106-108.
HIGH RIP CURRENT RISK FROM 7 AM TUESDAY THROUGH TUESDAY
EVENING FOR COASTAL PENDER AND COASTAL NEW HANOVER COUNTIES.
MARINE...SMALL CRAFT ADVISORY UNTIL 8 PM EDT TUESDAY FOR
AMZ250-252-254-256.
&&
$$
NEAR TERM...JDW/TRA
SHORT TERM...RJD
LONG TERM...SHK
AVIATION...SGL
TIDES/COASTAL FLOODING...JDW
AREA FORECAST DISCUSSION
NWS BISMARCK ND
916 PM CDT MON AUG 25 2014
.UPDATE...
ISSUED AT 913 PM CDT MON AUG 25 2014
ONLY CHANGE TO FORECAST WAS TO KEEP CLOUD COVER OVER PORTIONS OF
CENTRAL INTO WESTERN NORTH DAKOTA IN A BIT LONGER THIS EVENING AS
IT HAS BE RELUCTANT TO DISSIPATE OVER SOME LOCATIONS.
OTHERWISE...GOING FORECAST IS IN GOOD SHAPE. UPDATES HAVE BEEN SENT.
UPDATE ISSUED AT 611 PM CDT MON AUG 25 2014
A FEW SPRINKLES ARE RELUCTANT TO DISSIPATE OVER NORTHWEST NORTH
DAKOTA SO WILL KEEP THEM IN THE FORECAST FOR ANOTHER COUPLE OF
HOURS. OTHERWISE...GOING FORECAST APPEARS IN GOOD SHAPE WITH CLOUD
COVER STARTING TO SLOWLY DISSIPATE. UPDATES HAVE BEEN SENT.
&&
.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 00Z TAFS THROUGH 00Z TUESDAY EVENING)
ISSUED AT |611 PM CDT MON AUG 25 2014
MVFR CIGS OVER CENTRAL INTO PTNS OF WESTERN ND WILL CONTINUE TO
DISSIPATE AND LIFT THROUGH EARLY THIS EVENING. VFR CONDITIONS ARE
THEN EXPECTED TO PREVAIL.
&&
.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.
&&
$$
UPDATE...JJS
SHORT TERM...TWH
LONG TERM...JV
AVIATION...JJS
HYDROLOGY...TWH
AREA FORECAST DISCUSSION
NWS GRAND FORKS ND
650 PM CDT MON AUG 25 2014
.UPDATE...
ISSUED AT 641 PM CDT MON AUG 25 2014
CHALLENGE FOR OVERNIGHT WILL BE CLOUD COVERAGE AND IMPACT ON
MORNING TEMPS. CURRENT FORECAST HAS CLEARING OCCURRING BY MIDNIGHT FOR
THE VALLEY AND WEST. LATEST HRRR SUPPORTS THIS WHERE THE RUC
LINGERS LOW LEVEL MOISTURE UNTIL 09Z IN THE RRV AND THE NAM KEEPS
HIGHER RH THROUGH 12Z. SO FOR NOW WILL WATCH CLOUD TRENDS. IF
CLOUDS HOLD ON LONGER...WOULD NEED TO UP THE CURRENT MID 40S MIN
TEMPS FOR MORNING ON THE NEXT UPDATE.
&&
.SHORT TERM...(THIS EVENING THROUGH TUESDAY NIGHT)
ISSUED AT 258 PM CDT MON AUG 25 2014
TEMPERATURES WILL BE THE MAIN FORECAST ISSUE FOR THE SHORT TERM.
THE UPPER LOW THAT BROUGHT OUR RAIN OVER THE WEEKEND HAS PULLED
OFF INTO EASTERN ONTARIO THIS AFTERNOON AND WILL CONTINUE TO MOVE
AWAY FROM THE REGION OVERNIGHT. CLOUD COVER HAS BEEN VERY CELLULAR
TODAY OVER THE CWA AND THINK IT SHOULD DISSIPATE AFTER SUNSET.
HIGH PRESSURE WILL BUILD IN AND WINDS SHOULD DECREASE. A FEW OF
THE MODELS SHOW SOME 850MB TEMPS APPROACHING 0 C...AND MORNING OBS
IN CANADA HAD AROUND 3 C SO THE COLD TREND LOOKS REASONABLE.
CONTINUED TO KEEP LOWS OVERNIGHT IN THE LOW TO MID 40S WHICH FITS
WITH UPSTREAM DEW POINTS.
SPLIT FLOW ALOFT WILL CONTINUE INTO TOMORROW AS THE MAIN SOUTHERN
BRANCH UPPER LOW SETTLES IN OVER THE DESERT SOUTHWEST. SFC HIGH
PRESSURE CENTERED OVER THE NORTHERN PLAINS DURING THE MORNING
WILL MOVE OFF TO THE EAST DURING THE DAY. NOT A LOT OF TEMPERATURE
ADVECTION BUT THE AIR MASS WILL BE MODERATING AND THERE SHOULD BE
MORE SUNSHINE ON TUESDAY THAN THERE IS AVAILABLE TODAY. THINK WE
WILL BE ABLE TO GET WELL INTO THE 60S. THE ECMWF AND GEM HAVE SOME
PRECIP DEVELOPING ACROSS THE SOUTHERN COUNTIES DUE TO A NORTHERN
BRANCH SHORTWAVE...BUT WITH THE GFS AND NAM GOING DRY AND THE
TREND OF MODELS OVERDOING PRECIP LATELY WILL KEEP ANY POPS OUT FOR
NOW. SOUTHERLY WINDS AND SOME WEAK WARM AIR ADVECTION WILL GET
GOING TUESDAY NIGHT AS THE SFC HIGH MOVES FURTHER EAST AND A WEAK
TROUGH DEVELOPS OVER THE NORTHERN ROCKIES. TEMPS TUESDAY NIGHT
SHOULD BE A BIT HIGHER THAN WEDNESDAY...IN THE UPPER 40S TO LOW
50S.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 258 PM CDT MON AUG 25 2014
WEDNESDAY THROUGH THURSDAY...SPLIT FLOW ALOFT CONTINUES...WITH A
WEAK EMBEDDED SHORTWAVE POSSIBLE OVER SD AS THE SOUTHERN BRANCH
UPPER LOW MOVES OUT INTO THE CENTRAL PLAINS. A FEW OF THE MODELS
HAVE SOME PRECIP ENTERING OUR SOUTHERN CWA...BUT OTHERS HAVE THE
PRECIP AS FAR SOUTH AS THE NEB/SD BORDER. WILL CONTINUE TO KEEP
THE SOUTHERN COUNTIES DRY FOR NOW BUT WILL KEEP AN EYE ON THE
POSITION OF THE FRONTAL BOUNDARY AND ANY MINOR SHORTWAVES. TEMPS
SHOULD SLOWLY WARM BACK UP TOWARDS SEASONAL AVERAGES AS SOUTHERLY
WINDS DEVELOP AHEAD OF A WEAK SFC TROUGH TO OUR WEST.
FOR THU NIGHT THROUGH MONDAY...WILL GENERALLY BE STARTING THE PERIOD
WITH ZONAL FLOW ALOFT. 500MB HEIGHTS START TO RISE A BIT BY SAT/SAT
NIGHT BEFORE THEY SHIFT BACK TO ZONAL AGAIN. AT THE SFC A FRONTAL
BOUNDARY SAGS TOWARD THE CANADIAN BORDER THU NIGHT WHICH MAY RESULT
IN SCT SHOWERS AND TSTMS. THIS FRONT CONTINUES TO DROP SOUTHWARD ON
FRI/FRI NIGHT...KEEPING THE CHANCES FOR ADDITIONAL PCPN ALONG IT.
MOST OF THE AREA SHOULD BE DRY SAT/SAT NIGHT WITH SFC HIGH PRESSURE
NOSING IN. THEREAFTER ANOTHER FRONTAL BOUNDARY LOOKS TO MOVE IN BY
SUNDAY INTO MONDAY BRINGING ADDITIONAL CHANCES FOR PCPN WITH IT.
TEMPS ARE EXPECTED TO STAY JUST A BIT BELOW NORMAL.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z TUESDAY EVENING)
ISSUED AT 641 PM CDT MON AUG 25 2014
GUSTINESS HAS WANED AND WINDS WILL CONTINUE TO DIMINISH AS HIGH
PRESSURE APPROACHES THE REGION. DID DELAY THE SCT CIGS ABOUT 3 TO
4 HOURS AS BKN CIGS EXPECTED INTO THE OVERNIGHT HOURS.
&&
.FGF WATCHES/WARNINGS/ADVISORIES...
ND...NONE.
MN...NONE.
&&
$$
UPDATE...JK
SHORT TERM...JR
LONG TERM...JR/GODON
AVIATION...JK
AREA FORECAST DISCUSSION
NWS BISMARCK ND
618 PM CDT MON AUG 25 2014
.UPDATE...
ISSUED AT 611 PM CDT MON AUG 25 2014
A FEW SPRINKLES ARE RELUCTANT TO DISSIPATE OVER NORTHWEST NORTH
DAKOTA SO WILL KEEP THEM IN THE FORECAST FOR ANOTHER COUPLE OF
HOURS. OTHERWISE...GOING FORECAST APPEARS IN GOOD SHAPE WITH CLOUD
COVER STARTING TO SLOWLY DISSIPATE. UPDATES HAVE BEEN SENT.
&&
.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 00Z TAFS THROUGH 00Z TUESDAY EVENING)
ISSUED AT |611 PM CDT MON AUG 25 2014
MVFR CIGS OVER CENTRAL INTO PTNS OF WESTERN ND WILL CONTINUE TO
DISSIPATE AND LIFT THROUGH EARLY THIS EVENING. VFR CONDITIONS ARE
THEN EXPECTED TO PREVAIL.
&&
.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.
&&
$$
UPDATE...JJS
SHORT TERM...TWH
LONG TERM...JV
AVIATION...JJS
HYDROLOGY...TWH
AREA FORECAST DISCUSSION
NWS GRAND FORKS ND
1225 PM CDT SUN AUG 24 2014
.UPDATE...
ISSUED AT 1225 PM CDT SUN AUG 24 2014
MADE SOME FURTHER ADJUSTMENTS TO POPS/WX AS MOST OF THE PRECIP HAS
MOVED NORTH AND EAST OF THE CWA BUT MORE CONVECTION SEEMS TO BE
DEVELOPING IN THE DEVILS LAKE BASIN. SOME CLEARING BUT SKIES
REMAIN MOSTLY CLOUDY OVER A LARGE PORTION OF OUR AREA. WILL KEEP
AN EYE OUT FOR ADDITIONAL CLEARING AND IF ANY STRONG TO SEVERE
CONVECTION BREAKS OUT.
UPDATE ISSUED AT 949 AM CDT SUN AUG 24 2014
UPDATED POPS/WX FOR CURRENT RADAR TRENDS. CONVECTION NOW LIMITED
TO THE NORTHERN VALLEY AND A FEW ISOLATED CELLS POPPING UP FURTHER
SOUTH. MUCH OF THE DEVELOPMENT IN THE NEXT FEW HOURS WILL DEPEND
ON CLOUD COVER. THERE IS SOME DECENT CLEARING IN THE SOUTH CENTRAL
CWA...SO THERE COULD BE SOME DESTABILIZATION. RAP AND HRRR HAVE
REDEVELOPMENT MAINLY OVER THE NORTHERN COUNTIES IN THE 20-00Z TIME
FRAME THIS AFTERNOON. WILL CONTINUE TO KEEP SCATTERED POPS GOING
FOR MUCH OF THE DAY...ALTHOUGH SEVERITY IS STILL UNCERTAIN AT THIS
POINT SO WILL LEAVE OUT OF THE GRIDS UNTIL A LATER UPDATE. WILL
KEEP TEMPS ON TRACK TO TOP OUT IN THE 70S TO LOW 80S.
UPDATE ISSUED AT 635 AM CDT SUN AUG 24 2014
RADAR CURRENTLY SHOWING CLUSTER OF THUNDERSTORMS AND HEAVY RAIN
SHOWERS MAINLY NORTH OF HWY 2 CORRIDOR IN THE RED RIVER VALLEY AND
NORTHWEST MINNESOTA...AS WELL AS DOWN THROUGH BELTRAMI COUNTY.
SEEING SOME ISOLATED TSTM ACTIVITY BEHIND MAIN CLUSTER IN EASTERN
ND. HAVE UPDATED POP GRIDS TO REFLECT THIS. NO OTHER CHANGES MADE
THIS UPDATE.
&&
.SHORT TERM...(TODAY THROUGH MONDAY)
ISSUED AT 357 AM CDT SUN AUG 24 2014
CURRENT RADAR SHOWS A LINE OF THUNDERSTORMS FROM CENTRAL CASS
COUNTY THROUGH CENTRAL OTTER TAIL COUNTY MOVING NORTHWARD INTO WEST
CENTRAL AND NORTHWEST MINNESOTA AS WELL AS CONTINUING ACROSS FAR
EASTERN NORTH DAKOTA...ESPECIALLY BARNES...RANSOM...SARGENT AND
RICHLAND COUNTIES. THOSE FOUR COUNTIES HAVE RECEIVED THE MOST
PRECIPITATION BUT REMAIN BELOW FLASH FLOOD GUIDANCE AND A
HEADLINES FOR WIDESPREAD OVERLAND FLOODING IS NOT EXPECTED HOWEVER
LOCALIZED LOW AREAS COULD SEE STANDING WATER TOMORROW MORNING.
CURRENTLY THE HI RES MODELS HAVE THE BEST HANDLE ON THE
PRECIPITATION AND WILL BE USED THROUGH AROUND 18Z...WHEN THE
PRECIPITATION SHOULD LIFT OUT OF THE REGION AS THE LOW MOVES NORTH
AND A DRY SLOT MOVES INTO MY SOUTHWESTERN ZONES.
TODAY...DRY SLOT WILL MOVE ACROSS THE SOUTHERN VALLEY AND
PRECIPITATION SHOULD BE CONFINED TO MAINLY NORTH OF THE HWY 2
CORRIDOR AND THE FAR EAST. SOME MODELS DO SHOW CU/SHOWERS
DEVELOPING IN THE DRY SLOT BY LATE AFTN AND WILL KEEP SOME LOW
POPS IN MY SOUTHWESTERN ZONES. A SFC BNDRY STRETCHED FROM THE DVL
REGION INTO THE BJI AREA COULD BE THE SOURCE OF STRONG TO POSSIBLY
SEVERE THUNDERSTORMS IN THE NORTHERN VALLEY AND NW MINNESOTA THIS
AFTN...AS HEATING BECOMES MAXIMIZED AND DEEP LAYERED SHEAR
INCREASES TO AROUND 40 KTS BY 21Z. THERE WILL BE ONLY A SMALL
OPPORTUNITY TO HEAT OUT THIS AFTN...SO ATTM CONFIDENCE FOR SVR IS
LOW BUT STILL POSSIBLE. SPC HAS A SLIGHT RISK OUT FOR THIS REGION.
TONIGHT....PRECIP SHOULD BE CONFINED TO ALONG OR NORTH OF THE
INTERNATIONAL BORDER AND SOME LINGERING ISOLATED SHOWERS IN THE
FAR EAST. LOW WILL CONTINUE TO PULL NORTH AND PRECIP SHOULD END BY
MONDAY MORNING. A QUITE COOL AIRMASS WILL THEN WRAP INTO EASTERN
ND AS THE LOW PULLS NORTH...AND OVERNIGHT LOWS COULD DROP INTO THE
40S FOR PARTS OF THE FAR WESTERN CWA.
MONDAY...STRONG COLD ADVECTION INTO THE NORTHERN TIER WILL KEEP
DAYTIME HIGHS WELL BELOW SEASONAL NORMS...WITH THE DEVILS LAKE
BASIN STRUGGLING TO BREAK THE 60 MARK AND MOST OF THE REST OF THE
AREA SEEING DAYTIME HIGHS IN THE MID 60S TO NEAR 70. WINDS WILL BE
WESTERLY AND BREEZY...MAKING A RATHER CHILLY DAY FOR AUGUST. SOME
SHOWERS MAY LINGER ALONG THE INTL BORDER AS THE SFC LOW MOVES INTO
WRN ONTARIO AND HAVE KEPT LOW POPS ACROSS THE EXTREME NORTH.
.LONG TERM...(MONDAY NIGHT THROUGH SATURDAY)
ISSUED AT 357 AM CDT SUN AUG 24 2014
TUESDAY...UNSEASONALLY COOL TEMPERATURES WILL STAY IN PLACE
THROUGH TUESDAY AS SFC HIGH PRESSURE MOVES INTO THE AREA. DAYTIME
HIGHS WILL BE IN THE MID TO UPPER 60S.
BEYOND TUESDAY...LONG WAVE PATTERN FORECAST A ZONAL FLOW ACROSS SOUTHERN
CANADA DURING THIS PERIOD. THE ECMWF IS A FASTER SOLUTION THAN THE
GFS THROUGH THE PERIOD. ECMWF AND GFS HAS BEEN TRENDING SOUTH OVER
THE LAST COUPLE MODEL RUNS. WILL BLEND THE ECMWF AND GFS.
TRIMMED BACK POPS IN FAR SOUTHERN GRANT COUNTY WED AND WED NIGHT.
WILL SHIFT PRECIP EAST ON SAT.
LITTLE CHANGE TO TEMPS...A DEGREE OR SO HIGHER FOR WED AND SAT. NO
CHANGES TO THU OR FRI FROM YESTERDAYS RUN.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON)
ISSUED AT 1225 PM CDT SUN AUG 24 2014
EXPECT SOME MVFR/IFR CIGS BEFORE THE TROUGH MOVES THROUGH AND SHIFTS
WINDS MORE SW. ONCE WINDS TURN SW...EXPECT VFR CONDITIONS EXCEPT
NEAR ANY SHOWER/TSTORM THIS AFTERNOON MAINLY IN THE NORTH. WINDS
COULD GUST TO AROUND 25KT THROUGH THIS EVENING...DECREASE SOME
OVERNIGHT...THEN SHIFT MORE WESTERLY ON MONDAY. WINDS COULD ONCE
AGAIN BECOME A BIT GUSTY TO AROUND 25KT LATE IN THE TAF
PERIOD...WITH MVFR CIGS POSSIBLE IN CYCLONIC FLOW ALOFT.
&&
.FGF WATCHES/WARNINGS/ADVISORIES...
ND...NONE.
MN...NONE.
&&
$$
UPDATE...JR
SHORT TERM...SPEICHER
LONG TERM...HOPPES/SPEICHER
AVIATION...DK
AREA FORECAST DISCUSSION
NWS GRAND FORKS ND
949 AM CDT SUN AUG 24 2014
.UPDATE...
ISSUED AT 949 AM CDT SUN AUG 24 2014
UPDATED POPS/WX FOR CURRENT RADAR TRENDS. CONVECTION NOW LIMITED
TO THE NORTHERN VALLEY AND A FEW ISOLATED CELLS POPPING UP FURTHER
SOUTH. MUCH OF THE DEVELOPMENT IN THE NEXT FEW HOURS WILL DEPEND
ON CLOUD COVER. THERE IS SOME DECENT CLEARING IN THE SOUTH CENTRAL
CWA...SO THERE COULD BE SOME DESTABILIZATION. RAP AND HRRR HAVE
REDEVELOPMENT MAINLY OVER THE NORTHERN COUNTIES IN THE 20-00Z TIME
FRAME THIS AFTERNOON. WILL CONTINUE TO KEEP SCATTERED POPS GOING
FOR MUCH OF THE DAY...ALTHOUGH SEVERITY IS STILL UNCERTAIN AT THIS
POINT SO WILL LEAVE OUT OF THE GRIDS UNTIL A LATER UPDATE. WILL
KEEP TEMPS ON TRACK TO TOP OUT IN THE 70S TO LOW 80S.
UPDATE ISSUED AT 635 AM CDT SUN AUG 24 2014
RADAR CURRENTLY SHOWING CLUSTER OF THUNDERSTORMS AND HEAVY RAIN
SHOWERS MAINLY NORTH OF HWY 2 CORRIDOR IN THE RED RIVER VALLEY AND
NORTHWEST MINNESOTA...AS WELL AS DOWN THROUGH BELTRAMI COUNTY.
SEEING SOME ISOLATED TSTM ACTIVITY BEHIND MAIN CLUSTER IN EASTERN
ND. HAVE UPDATED POP GRIDS TO REFLECT THIS. NO OTHER CHANGES MADE
THIS UPDATE.
&&
.SHORT TERM...(TODAY THROUGH MONDAY)
ISSUED AT 357 AM CDT SUN AUG 24 2014
CURRENT RADAR SHOWS A LINE OF THUNDERSTORMS FROM CENTRAL CASS
COUNTY THROUGH CENTRAL OTTER TAIL COUNTY MOVING NORTHWARD INTO WEST
CENTRAL AND NORTHWEST MINNESOTA AS WELL AS CONTINUING ACROSS FAR
EASTERN NORTH DAKOTA...ESPECIALLY BARNES...RANSOM...SARGENT AND
RICHLAND COUNTIES. THOSE FOUR COUNTIES HAVE RECEIVED THE MOST
PRECIPITATION BUT REMAIN BELOW FLASH FLOOD GUIDANCE AND A
HEADLINES FOR WIDESPREAD OVERLAND FLOODING IS NOT EXPECTED HOWEVER
LOCALIZED LOW AREAS COULD SEE STANDING WATER TOMORROW MORNING.
CURRENTLY THE HI RES MODELS HAVE THE BEST HANDLE ON THE
PRECIPITATION AND WILL BE USED THROUGH AROUND 18Z...WHEN THE
PRECIPITATION SHOULD LIFT OUT OF THE REGION AS THE LOW MOVES NORTH
AND A DRY SLOT MOVES INTO MY SOUTHWESTERN ZONES.
TODAY...DRY SLOT WILL MOVE ACROSS THE SOUTHERN VALLEY AND
PRECIPITATION SHOULD BE CONFINED TO MAINLY NORTH OF THE HWY 2
CORRIDOR AND THE FAR EAST. SOME MODELS DO SHOW CU/SHOWERS
DEVELOPING IN THE DRY SLOT BY LATE AFTN AND WILL KEEP SOME LOW
POPS IN MY SOUTHWESTERN ZONES. A SFC BNDRY STRETCHED FROM THE DVL
REGION INTO THE BJI AREA COULD BE THE SOURCE OF STRONG TO POSSIBLY
SEVERE THUNDERSTORMS IN THE NORTHERN VALLEY AND NW MINNESOTA THIS
AFTN...AS HEATING BECOMES MAXIMIZED AND DEEP LAYERED SHEAR
INCREASES TO AROUND 40 KTS BY 21Z. THERE WILL BE ONLY A SMALL
OPPORTUNITY TO HEAT OUT THIS AFTN...SO ATTM CONFIDENCE FOR SVR IS
LOW BUT STILL POSSIBLE. SPC HAS A SLIGHT RISK OUT FOR THIS REGION.
TONIGHT....PRECIP SHOULD BE CONFINED TO ALONG OR NORTH OF THE
INTERNATIONAL BORDER AND SOME LINGERING ISOLATED SHOWERS IN THE
FAR EAST. LOW WILL CONTINUE TO PULL NORTH AND PRECIP SHOULD END BY
MONDAY MORNING. A QUITE COOL AIRMASS WILL THEN WRAP INTO EASTERN
ND AS THE LOW PULLS NORTH...AND OVERNIGHT LOWS COULD DROP INTO THE
40S FOR PARTS OF THE FAR WESTERN CWA.
MONDAY...STRONG COLD ADVECTION INTO THE NORTHERN TIER WILL KEEP
DAYTIME HIGHS WELL BELOW SEASONAL NORMS...WITH THE DEVILS LAKE
BASIN STRUGGLING TO BREAK THE 60 MARK AND MOST OF THE REST OF THE
AREA SEEING DAYTIME HIGHS IN THE MID 60S TO NEAR 70. WINDS WILL BE
WESTERLY AND BREEZY...MAKING A RATHER CHILLY DAY FOR AUGUST. SOME
SHOWERS MAY LINGER ALONG THE INTL BORDER AS THE SFC LOW MOVES INTO
WRN ONTARIO AND HAVE KEPT LOW POPS ACROSS THE EXTREME NORTH.
.LONG TERM...(MONDAY NIGHT THROUGH SATURDAY)
ISSUED AT 357 AM CDT SUN AUG 24 2014
TUESDAY...UNSEASONALLY COOL TEMPERATURES WILL STAY IN PLACE
THROUGH TUESDAY AS SFC HIGH PRESSURE MOVES INTO THE AREA. DAYTIME
HIGHS WILL BE IN THE MID TO UPPER 60S.
BEYOND TUESDAY...LONG WAVE PATTERN FORECAST A ZONAL FLOW ACROSS SOUTHERN
CANADA DURING THIS PERIOD. THE ECMWF IS A FASTER SOLUTION THAN THE
GFS THROUGH THE PERIOD. ECMWF AND GFS HAS BEEN TRENDING SOUTH OVER
THE LAST COUPLE MODEL RUNS. WILL BLEND THE ECMWF AND GFS.
TRIMMED BACK POPS IN FAR SOUTHERN GRANT COUNTY WED AND WED NIGHT.
WILL SHIFT PRECIP EAST ON SAT.
LITTLE CHANGE TO TEMPS...A DEGREE OR SO HIGHER FOR WED AND SAT. NO
CHANGES TO THU OR FRI FROM YESTERDAYS RUN.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z MONDAY MORNING)
ISSUED AT 635 AM CDT SUN AUG 24 2014
SHRA AND TSTMS NORTH OF GFK AND OVER TVF WILL CONTINUE NORTH THIS
MORNING WITH SOME REDEVELOPING TSRA POSSIBLY MOVING INTO GFK
AREA BY MID MORNING. OVERALL IFR CIGS AT TAF ISSUANCE SHOULD CLIMB
TO MVFR BY MID MORNING...AND HOLD ON THROUGH MUCH OF THE DAY AT
ALL SITES EXCEPT FAR. DO NOT LOOK FOR ANY CLEARING UNTIL AFT
00Z...WHEN WINDS WILL SHIFT SO SW FLOW AND SKIES WILL BEGIN TO
CLEAR. WIND SPEEDS WILL INCREASE THROUGHOUT THE NIGHT AT DVL.
&&
.FGF WATCHES/WARNINGS/ADVISORIES...
ND...NONE.
MN...NONE.
&&
$$
UPDATE...JR
SHORT TERM...SPEICHER
LONG TERM...HOPPES/SPEICHER
AVIATION...SPEICHER
AREA FORECAST DISCUSSION
NWS BISMARCK ND
1209 AM CDT SUN AUG 24 2014
.UPDATE...
ISSUED AT 1209 AM CDT SUN AUG 24 2014
LATEST WATER VAPOR IMAGERY SHOWS AN UPPER LOW CIRCULATING IN
NORTHEAST WYOMING. THE SURFACE LOW WAS REFLECTED OVER BISMARCK
WITH A NORTHWARD MOVEMENT FORECAST AS 3HR MAX PRESSURE FALLS
RESIDED OVER MINOT. WITH THE POSITION OF THE UPPER/SURFACE LOW...A
DRY SLOT IS EVIDENT ON THE WATER VAPOR AND ALSO PER LATEST
LOCAL/REGIONAL RADAR WITH MINIMAL PRECIPITATION OVER THE SOUTHWEST
AND SOUTH CENTRAL. HAVE INCLUDED AREAS OF FOG SOUTHWEST AND PATCHY
FOG ELSEWHERE FOR THE REMAINING PORTION OF THE OVERNIGHT PERIOD.
EXPECT STEADY RAINS CONTINUING IN THE NORTH OVERNIGHT. CURRENT
FORECAST OVERALL IS IN GOOD SHAPE.
UPDATE ISSUED AT 921 PM CDT SAT AUG 23 2014
SEVERAL AREAS OF HEAVY RAIN REMAIN A CONCERN THIS EVENING AND
OVERNIGHT. FIRST...THE FLASH FLOOD WATCH HAS BEEN TRIMMED TO
INCLUDE NOW THE AREAS ALONG AND NORTH OF LAKE SAKAKAWEA AS THE
RAIN SHIELD HAS MOVED NORTH. THIS REPRESENTS FUTURE FLOOD
POTENTIAL TONIGHT AND SUNDAY. TWO AREAS THAT HAVE ALREADY RECEIVED
HEAVY RAIN AND REPORTED OVERLAND FLOODING HAVE FLOOD ADVISORIES
ONGOING. THE FIRST AREA INCLUDES DICKEY AND LAMOURE COUNTIES WHERE
ONGOING TRAINING THUNDERSTORMS LEFT STREET FLOODING IN ELLENDALE.
THE HEAVY RAINFALL SHOULD LAST ANOTHER COUPLE OF HOURS FOLLOWED BY
SLOWLY RECEDING WATER. ANOTHER FLOOD ADVISORY REMAINS IN EFFECT FOR
THE SOUTHWEST WHERE WIDESPREAD 2 INCHES OF RAIN FELL TODAY. WITHIN
THIS AREA AN ENHANCED AREA OF HEAVY RAINFALL...PERHAPS UP TO 4
INCHES...STRETCHES FROM WESTERN SIOUX...CENTRAL GRANT...CENTRAL
MORTON COUNTY NEAR GLEN ULLIN...INTO MERCER COUNTY. WILL KEEP THE
FLOOD ADVISORY GOING FOR THIS AREA AS WELL TONIGHT.
UPDATE ISSUED AT 717 PM CDT SAT AUG 23 2014
FIRST WAVE OF HEAVY RAIN HAS PASSED THROUGH THE SOUTHWEST. SO FAR
WIDESPREAD REPORTS OF AROUND 2 INCHES WITH UPWARDS OF 3 INCHES IN
PLACES. THE RAIN SHIELD IS MOVING INTO THE NORTH CENTRAL FOR THE
REMAINDER OF THE EVENING. SEVERAL LONG LIVED THUNDERSTORMS MOVING
THROUGH NORTHWEST SOUTH DAKOTA SO WILL KEEP FLASH FLOOD WATCH AND
ADVISORIES GOING SOUTHWEST FOR A LITTLE WHILE LONGER. CLUSTER OF
MORE VIGOROUS THUNDERS TOMS MOVING TROUGH SOUTHEAST NORTH DAKOTA.
SEVERE POTENTIAL LIMITED WIND GUSTS TO 40 AND HEAVY RAIN LIKELY
THERE. MID 50S FOR THE HIGH TEMP TODAY NORTHWEST NORTH DAKOTA.
&&
.SHORT TERM...(THIS EVENING THROUGH SUNDAY)
ISSUED AT 300 PM CDT SAT AUG 23 2014
THE MAIN FORECAST ISSUE IN THE SHORT TERM PERIOD WILL BE HEAVY
RAIN LATE THIS AFTERNOON AND THIS EVENING. THEN ENDING ACROSS THE
SOUTH LATE THIS EVENING BUT CONTINUING ACROSS THE NORTH INTO
SUNDAY.
LATEST RADAR ESTIMATES HAVE MATCHED UP WELL WITH OBSERVED REPORTS
ACROSS SOUTHWEST NORTH DAKOTA. GENERALLY 1 TO 1.5 INCHES REPORTED
SOUTH AND WEST OF A LINE FROM SELFRIDGE TO THEODORE ROOSEVELT NP.
DID GET A REPORT FROM WFO BILLINGS OF CLOSER TO 5 INCHES NEAR
BAKER MT. AS OF YET CALLS TO SPOTTERS AND BOWMAN EM HAVE RESULTED
IN NO SIGNIFICANT FLOODING ISSUES. HOWEVER...WE HAVE ISSUED AN
AREAL FLOOD ADVISORY SOUTH AND WEST OF LAKE SAKAKAWEA AND THE
MISSOURI RIVER...TO COVER THE 1 TO 1.5 INCHES OF RAIN THAT HAS
FALLEN IN ADDITION TO ADDITIONAL EXPECTED RAIN THROUGH THE
AFTERNOON AND TONIGHT.
REGARDING THE CURRENT FLOOD WATCH AND POTENTIAL OF SEVERE
WEATHER...
WILL LET THE WATCH CONTINUE. HEAVIEST RAIN HAS FALLEN
ACROSS THE MOST SATURATED SOILS IN THE SOUTHWEST. THE HEAVIEST
ADDITIONAL ACCUMULATIONS TONIGHT SHOULD BE CENTERED ACROSS THE
NORTH CENTRAL AND NORTHWEST. IF WE HAD TO PARE IT DOWN...WOULD
PROBABLY REMOVE WELLS SOUTH THROUGH MCINTOSH. HOWEVER...THERE IS
STILL A THREAT OF AFTERNOON AND EVENING CONVECTION HERE AS THE
SURFACE LOW LIFTS INTO NORTH DAKOTA. THUS WILL CONTINUE AS IS FOR
NOW. THE LATEST HRRR STILL DEVELOPS SCATTERED CONVECTION IN THIS
AREA THIS EVENING. HOWEVER THE STRONGEST CONVECTION IS NOW BEING
PLACED TO THE SOUTH OF THE CWA. WITH OUR EAST TO NORTHEAST FLOW AND
COOLER TEMPERATURES OVER NORTH DAKOTA THIS SEEMS REASONABLE...BUT
WITH THE SURFACE LOW LIFTING INTO CENTRAL NORTH DAKOTA THINK OUR
SOUTHEAST CWA WILL BE IN A FAVORED LOCATION FOR ABUNDANT LOW LEVEL
HELICITY THUS WILL CONTINUE A MENTION OF SEVERE OVER THE SOUTHEAST
CWA.
WE DRY OUT FROM SOUTH TO NORTH LATE THIS EVENING THROUGH SUNDAY.
HIGHEST POPS WILL REMAIN OVER THE NORTHWEST AND FAR NORTH CENTRAL.
WITH THE UPPER LEVEL SLOW LIFTING THROUGH EASTERN MONTANA INTO
NORTHWEST ND...THERE SHOULD STILL BE ENOUGH MID TO UPPER LEVEL
FORCING TO MENTION ISOLATED THUNDER THROUGH THE DAY WHEREVER WE
HAVE A MENTION OF SHOWERS.
.LONG TERM...(SUNDAY NIGHT THROUGH SATURDAY)
ISSUED AT 300 PM CDT SAT AUG 23 2014
SUNDAY EVENING THE UPPER LEVEL LOW IS PROGGED TO BE AT THE BORDER OF
MONTANA AND NORTH DAKOTA...WITH THE SURFACE LOW ALONG THE NORTH
DAKOTA/CANADIAN/MINNESOTA BORDER. THE ELONGATED SURFACE LOW/FRONT
COMBINED WITH THE UPPER LOW TO THE WEST WILL KEEP HIGH CHANCES OF
SHOWERS IN THE NORTHWEST/NORTH CENTRAL SUNDAY NIGHT.
THE SYSTEM LIFTS NORTHEASTWARD SUNDAY NIGHT AND INTO MONDAY...WITH
COLD ADVECTION IN ITS WAKE. LOOKING AT LOWS SUNDAY NIGHT IN THE 40S
WEST TO LOWER 50S IN THE JAMES VALLEY. MOSTLY CLOUDY SKIES NORTH
MONDAY WILL KEEP MAXIMUM TEMPERATURES CONFINED TO THE UPPER 50S WITH
60S SOUTH. BY TUESDAY MORNING THE SURFACE HIGH SETTLES OVER NORTH
DAKOTA...AND LOW TEMPERATURES SHOULD BE IN THE 40S ACROSS WESTERN
AND CENTRAL NORTH DAKOTA.
DURING THE DAY TUESDAY THROUGH WEDNESDAY THE TRAILING UPPER LEVEL
TROUGH MOVES EAST ACROSS THE NORTHERN PLAINS...WITH ISOLATED TO
SCATTERED SHOWERS POSSIBLE. MINOR UPPER LEVEL RIDGING OCCURS
WEDNESDAY NIGHT THROUGH FRIDAY. THE APPROACH OF ANOTHER ROCKIES
TROUGH TOWARDS NEXT WEEKEND MAY BE THE NEXT CHANCE OF SHOWERS AND
THUNDERSTORMS. A SLOW WARMING TREND WITH HIGHS TUESDAY IN THE 60S
WARMING TO THE 80S BY FRIDAY.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT)
ISSUED AT 1209 AM CDT SUN AUG 24 2014
AREAS OF FOG AND VCSH DOMINATE THE SOUTHERN TERMINALS FOR THE
OVERNIGHT PERIOD AT KDIK/KBIS/KJMS...WHILE STEADY RAINS WILL
CONTINUE AT KISN/KMOT. CIGS WILL REMAIN IN THE LIFR/IFR RANGE
ESPECIALLY NORTH...WITH POCKETS OF MVFR AT KBIS/KJMS. TRENDS SHOW
MAINLY MVFR CIGS DURING THE DAYLIGHT HOURS SUNDAY ACROSS THE
AERODROMES...WITH KJMS IMPROVING TO VFR AFTER 18Z SUNDAY.
&&
.HYDROLOGY...
ISSUED AT 1209 AM CDT SUN AUG 24 2014
A FLOOD WATCH HAS BEEN ISSUED FOR THE KNIFE RIVER NEAR HAZEN AND
FOR SPRING CREEK AT ZAP AS RIVER LEVELS ARE PROJECTED TO RISE INTO
MINOR FLOOD STAGE OVER THE NEXT 24HR PERIOD. WILL CONTINUE TO
MONITOR THE TRENDS THROUGHOUT THE NIGHT AND INTO THE DAY SUNDAY.
MODERATE TO HEAVY RAINS OVER THE PAST WEEK HAVE KEPT SOIL MOISTURE
ABNORMALLY HIGH ACROSS WESTERN AND CENTRAL NORTH DAKOTA. RAINFALL
THAT OCCURRED TODAY...ALONG WITH THE EXPECTED RAINFALL INTO TONIGHT
MAY LIKELY LEAD TO SOME OVERLAND FLOODING...ALONG WITH INCREASED
FLOWS INTO CREEKS...STREAMS...AND RIVERS.
ALONG WITH THE FLOOD WATCH THAT WAS ISSUED ON FRIDAY FOR TODAY
THROUGH SUNDAY...HAVE ALSO ISSUED AN AREAL FLOOD ADVISORY FOR THE
AREA SOUTH AND WEST OF THE MISSOURI RIVER. RADAR ESTIMATES WERE IN
AGREEMENT WITH SOME RAINFALL REPORTS OF 1 TO 1.5 INCHES OF RAINFALL
SO FAR TODAY. IN ADDITION...WHILE THERE IS NO REASONABLE EXPECTATION
OF MAJOR RIVER FLOODING...AT A MINIMUM THERE WILL BE SIGNIFICANT
WITHIN BANK RISES...AND MINOR RIVER FLOODING CANNOT BE RULED OUT.
.BIS WATCHES/WARNINGS/ADVISORIES...
FLOOD WATCH THROUGH SUNDAY AFTERNOON FOR NDZ001>005-009>013-
017>023-031>036-040>047-050.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
FLOOD WATCH THROUGH SUNDAY AFTERNOON FOR NDZ001>005-009>013-
021>023.
&&
$$
UPDATE...KS
SHORT TERM...TWH
LONG TERM...JV
AVIATION...KS
AREA FORECAST DISCUSSION
NWS CLEVELAND OH
144 PM EDT SUN AUG 24 2014
.SYNOPSIS...
HIGH PRESSURE OVER QUEBEC WILL BUILD SOUTH ACROSS THE EASTERN GREAT
LAKES THEN DRIFT TOWARD THE MID ATLANTIC COAST THROUGH TUESDAY.
LOW PRESSURE WILL PASS NORTH OF THE GREAT LAKES TUESDAY WITH A
FRONTAL BOUNDARY SLOWLY SINKING SOUTH ACROSS THE AREA THROUGH THE
MIDDLE OF THE WEEK.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
STRATUS DECK IN NW OHIO CONTINUES TO GRADUALLY ERODE AROUND THE
EDGES. UNFORTUNATELY IT WILL STILL TAKE A FEW MORE HOURS FOR THIS
TO REACH SANDUSKY/SENECA COUNTIES. IN THE EAST...THE 12Z PBZ
SOUNDING DID SHOW A HIGH AMOUNT OF LOW LEVEL MOISTURE THROUGH
2000 FEET BENEATH A VERY DRY LAYER ALOFT. CLOUDS HAVE FILLED IN
BUT WILL START TO MIX INTO THIS DRIER AIR AND START TO SCATTER OUT
BY 3-4 PM. LAST COUPLE RUNS OF THE RUC HAVE BEEN DOING A BETTER
JOB WITH THE CLOUD COVER ACROSS NE OHIO/NW PA AND AGREE WITH THAT TIMING.
GIVEN THE OVERCAST CONDITIONS IN MANY AREAS...ADJUSTED THE
FORECAST TO READ MOSTLY CLOUDY FOR PORTIONS OF NE OHIO/NW PA. ALSO
LOWERED HIGHS A COUPLE DEGREES IN THE WESTERN AND EASTERN PORTION
OF THE FORECAST AREA WITH HIGHS OCCURRING LATE THIS AFTERNOON AS
CLOUDS START TO CLEAR AT MANY SITES.
PREVIOUS DISCUSSION...
UPPER LEVEL HIGH PRESSURE WILL BUILD OVER THE REGION TODAY AS A
SURFACE HIGH DRIFTS SLOWLY SOUTHWARD OVER THE EASTERN GREAT LAKES
FROM QUEBEC. THIS SHOULD MEAN SINKING AIR OVER MOST OF THE REGION.
HOWEVER WE WILL NEED TO MONITOR AN AREA OF CONVERGENCE THAT WILL
SET UP ACROSS THE WESTERN COUNTY WARNING AREA FROM SANDUSKY TO
NEAR FINDLAY. IF THE AFTERNOON HEATING AND CONVERGENCE ALONG THIS
BOUNDARY ARE ENOUGH THERE MAY BE AN ISOLATED STORM OR TWO.
OTHERWISE WE WILL ERODE THE LOW LEVEL STRATOCUMULUS THIS MORNING
THEN WARM THE REGION UP WITH HIGHS A COUPLE DEGREES WARMER THAN
YESTERDAY.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH WEDNESDAY NIGHT/...
THE UPPER LEVEL RIDGE WILL SLOWLY WEAKEN INTO WEDNESDAY AS SURFACE
HIGH PRESSURE SETTLES TO THE MIDDLE ATLANTIC STATES. THIS SHOULD
ALLOW FOR AN INCREASE IN MOISTURE AND HEAT INTO THE REGION. HAVE
NUDGED HIGHS UP A COUPLE DEGREES FROM WHAT GUIDANCE IS INDICATING.
THIS WILL ALLOW PORTIONS OF THE REGION TO MAKE A RUN AT 90 DEGREES
FOR TUESDAY INTO WEDNESDAY AS LONG AS ANY CONVECTIVE DEBRIS
CLOUDINESS REMAINS THIN AND SCATTERED.
THUNDERSTORM CHANCES WILL SLOWLY INCREASE TUESDAY INTO WEDNESDAY.
TUESDAY MAY SEE CONVECTION DEVELOP ALONG A LAKE BREEZE. THE BEST
CONVERGENCE ALONG THIS BOUNDARY WILL BE FROM JUST EAST OF
CLEVELAND INTO NW PA. BY WEDNESDAY A COLD FRONT MAY BE CLOSE
ENOUGH TO BRING THUNDERSTORMS TO THE REGION DURING THE AFTERNOON
AND OVERNIGHT. LAST LOOK AT THE ECMWF INDICATES THAT THIS FRONT
MAY MOVE THROUGH FASTER. WILL HAVE TO MONITOR THIS THE NEXT
COUPLE DAYS AND TWEAK THE TIMING OF THE THUNDERSTORMS ON WEDNESDAY
AS NEEDED.
&&
.LONG TERM /THURSDAY THROUGH SATURDAY/...
THE MODELS ARE MORE IN AGREEMENT IN MOVING A WAVE ALONG THE FRONT
STALLED OVER THE AREA THU THRU FRI WITH THE GFS BEING A LITTLE
MORE PROGRESSIVE WITH THE FRONT. WILL KEEP A GOOD CHANCE FOR
SHRA/TSRA GOING THU AND FRI THEN SHOW SOME DECREASE IN POP FOR SAT
IN CASE THE GFS IS MORE RIGHT. EVEN THE ECMWF DOES SHOW A DECREASE
IN MOISTURE OVER THE AREA BY LATE SAT. TEMPS WILL BE TRICKY DUE TO
THE ULTIMATE POSITION OF THE FRONT AND WIND DIRECTION.
&&
.AVIATION /18Z SUNDAY THROUGH FRIDAY/...
PATCHES OF MVFR STRATOCUMULUS (BKN020-BKN030) WILL SLOWLY LIFT TO
VFR LAYER AND SCATTER OUT THIS AFTERNOON. PATCHES OF MVFR AND IFR
STRATOCUMULUS DECK WILL REDEVELOP LATE TONIGHT AND MONDAY MORNING
AS THE BOUNDARY LAYER REMAINS MOIST. FOG MAY GET IFR DENSE IN SOME
AREAS ESPECIALLY ACROSS NORTH CENTRAL OHIO AND NORTHWEST OHIO
EARLY MONDAY MORNING. MORE OF THE SAME ON MONDAY WITH MVFR
CEILINGS LIFTING TO VFR AND SCATTERING OUT.
OUTLOOK...VFR EXCEPT FOR MORNING FOG TUESDAY. NON VFR POSSIBLE
WEDNESDAY IN SHOWERS AND THUNDERSTORMS.
&&
.MARINE...
ENE WINDS OF 10 TO 20 KNOTS SHOULD SETTLE DOWN A LITTLE TODAY SO
NEAR SCA WAVES OF 2 TO 4 FEET SHOULD SUBSIDE TO 1 TO 3 FEET. WINDS
MAY PICK BACK UP A LITTLE THIS EVENING BUT THEN SHOULD START TURNING
SE AS THE HIGH OVER NY STATE DRIFTS SE TO THE NJ COAST FOR MON.
WINDS WILL VEER TO S TO SW FOR TUE AHEAD OF AN APPROACHING COLD
FRONT. RIGHT NOW IT LOOKS LIKE THE COLD FRONT WILL SAG INTO LAKE
ERIE BY LATE WED OR WED NIGHT THEN STALL AS A WAVE OF LOW PRESSURE
MOVES ALONG THE FRONT. WINDS ARE EXPECTED TO STAY 15 KNOTS OR LESS
BUT WIND DIRECTION IS IN QUESTION DUE TO THE UNCERTAINTY OF THE
EXACT POSITION OF THE FRONT WED NIGHT THRU THU.
&&
.CLE WATCHES/WARNINGS/ADVISORIES...
OH...NONE.
PA...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...MULLEN
NEAR TERM...KEC/MULLEN
SHORT TERM...MULLEN
LONG TERM...ADAMS
AVIATION...KOSARIK
MARINE...ADAMS
AREA FORECAST DISCUSSION
NWS CLEVELAND OH
1232 PM EDT SUN AUG 24 2014
.SYNOPSIS...
HIGH PRESSURE OVER QUEBEC WILL BUILD SOUTH ACROSS THE EASTERN GREAT
LAKES THEN DRIFT TOWARD THE MID ATLANTIC COAST THROUGH TUESDAY.
LOW PRESSURE WILL PASS NORTH OF THE GREAT LAKES TUESDAY WITH A
FRONTAL BOUNDARY SLOWLY SINKING SOUTH ACROSS THE AREA THROUGH THE
MIDDLE OF THE WEEK.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
STRATUS DECK IN NW OHIO CONTINUES TO GRADUALLY ERODE AROUND THE
EDGES. UNFORTUNATELY IT WILL STILL TAKE A FEW MORE HOURS FOR THIS
TO REACH SANDUSKY/SENECA COUNTIES. IN THE EAST...THE 12Z PBZ
SOUNDING DID SHOW A HIGH AMOUNT OF LOW LEVEL MOISTURE THROUGH
2000 FEET BENEATH A VERY DRY LAYER ALOFT. CLOUDS HAVE FILLED IN
BUT WILL START TO MIX INTO THIS DRIER AIR AND START TO SCATTER OUT
BY 3-4 PM. LAST COUPLE RUNS OF THE RUC HAVE BEEN DOING A BETTER
JOB WITH THE CLOUD COVER ACROSS NE OHIO/NW PA AND AGREE WITH THAT TIMING.
GIVEN THE OVERCAST CONDITIONS IN MANY AREAS...ADJUSTED THE
FORECAST TO READ MOSTLY CLOUDY FOR PORTIONS OF NE OHIO/NW PA. ALSO
LOWERED HIGHS A COUPLE DEGREES IN THE WESTERN AND EASTERN PORTION
OF THE FORECAST AREA WITH HIGHS OCCURRING LATE THIS AFTERNOON AS
CLOUDS START TO CLEAR AT MANY SITES.
PREVIOUS DISCUSSION...
UPPER LEVEL HIGH PRESSURE WILL BUILD OVER THE REGION TODAY AS A
SURFACE HIGH DRIFTS SLOWLY SOUTHWARD OVER THE EASTERN GREAT LAKES
FROM QUEBEC. THIS SHOULD MEAN SINKING AIR OVER MOST OF THE REGION.
HOWEVER WE WILL NEED TO MONITOR AN AREA OF CONVERGENCE THAT WILL
SET UP ACROSS THE WESTERN COUNTY WARNING AREA FROM SANDUSKY TO
NEAR FINDLAY. IF THE AFTERNOON HEATING AND CONVERGENCE ALONG THIS
BOUNDARY ARE ENOUGH THERE MAY BE AN ISOLATED STORM OR TWO.
OTHERWISE WE WILL ERODE THE LOW LEVEL STRATOCUMULUS THIS MORNING
THEN WARM THE REGION UP WITH HIGHS A COUPLE DEGREES WARMER THAN
YESTERDAY.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH WEDNESDAY NIGHT/...
THE UPPER LEVEL RIDGE WILL SLOWLY WEAKEN INTO WEDNESDAY AS SURFACE
HIGH PRESSURE SETTLES TO THE MIDDLE ATLANTIC STATES. THIS SHOULD
ALLOW FOR AN INCREASE IN MOISTURE AND HEAT INTO THE REGION. HAVE
NUDGED HIGHS UP A COUPLE DEGREES FROM WHAT GUIDANCE IS INDICATING.
THIS WILL ALLOW PORTIONS OF THE REGION TO MAKE A RUN AT 90 DEGREES
FOR TUESDAY INTO WEDNESDAY AS LONG AS ANY CONVECTIVE DEBRIS
CLOUDINESS REMAINS THIN AND SCATTERED.
THUNDERSTORM CHANCES WILL SLOWLY INCREASE TUESDAY INTO WEDNESDAY.
TUESDAY MAY SEE CONVECTION DEVELOP ALONG A LAKE BREEZE. THE BEST
CONVERGENCE ALONG THIS BOUNDARY WILL BE FROM JUST EAST OF
CLEVELAND INTO NW PA. BY WEDNESDAY A COLD FRONT MAY BE CLOSE
ENOUGH TO BRING THUNDERSTORMS TO THE REGION DURING THE AFTERNOON
AND OVERNIGHT. LAST LOOK AT THE ECMWF INDICATES THAT THIS FRONT
MAY MOVE THROUGH FASTER. WILL HAVE TO MONITOR THIS THE NEXT
COUPLE DAYS AND TWEAK THE TIMING OF THE THUNDERSTORMS ON WEDNESDAY
AS NEEDED.
&&
.LONG TERM /THURSDAY THROUGH SATURDAY/...
THE MODELS ARE MORE IN AGREEMENT IN MOVING A WAVE ALONG THE FRONT
STALLED OVER THE AREA THU THRU FRI WITH THE GFS BEING A LITTLE
MORE PROGRESSIVE WITH THE FRONT. WILL KEEP A GOOD CHANCE FOR
SHRA/TSRA GOING THU AND FRI THEN SHOW SOME DECREASE IN POP FOR SAT
IN CASE THE GFS IS MORE RIGHT. EVEN THE ECMWF DOES SHOW A DECREASE
IN MOISTURE OVER THE AREA BY LATE SAT. TEMPS WILL BE TRICKY DUE TO
THE ULTIMATE POSITION OF THE FRONT AND WIND DIRECTION.
&&
.AVIATION /12Z SUNDAY THROUGH THURSDAY/...
THE FOG AND STRATUS WILL BURN OFF BY 14 OR 15Z AT THE LATEST. LOW
LEVEL MOISTURE OVER THE EAST HALF OF THE AREA MAY KEEP THE DAYTIME
CU FIELD IN THE MVFR RANGE WHILE THE WEST SHOULD SEE THE CU AT VFR
LEVELS BY AFTERNOON. SOME HIGHER CLOUDS WILL ALSO BE SPREADING WEST
TO EAST OVER THE AREA TODAY AND TONIGHT. THESE ADDED HIGHER CLOUDS
AND JUST ENOUGH WIND SHOULD HELP TO LIMIT DENSE FOG DEVELOPMENT LATE
TONIGHT.
OUTLOOK...VFR EXCEPT FOR MORNING FOG TUESDAY. NON VFR POSSIBLE
WEDNESDAY AND THURSDAY WITH SCATTERED SHOWERS AND THUNDERSTORMS.
&&
.MARINE...
ENE WINDS OF 10 TO 20 KNOTS SHOULD SETTLE DOWN A LITTLE TODAY SO
NEAR SCA WAVES OF 2 TO 4 FEET SHOULD SUBSIDE TO 1 TO 3 FEET. WINDS
MAY PICK BACK UP A LITTLE THIS EVENING BUT THEN SHOULD START TURNING
SE AS THE HIGH OVER NY STATE DRIFTS SE TO THE NJ COAST FOR MON.
WINDS WILL VEER TO S TO SW FOR TUE AHEAD OF AN APPROACHING COLD
FRONT. RIGHT NOW IT LOOKS LIKE THE COLD FRONT WILL SAG INTO LAKE
ERIE BY LATE WED OR WED NIGHT THEN STALL AS A WAVE OF LOW PRESSURE
MOVES ALONG THE FRONT. WINDS ARE EXPECTED TO STAY 15 KNOTS OR LESS
BUT WIND DIRECTION IS IN QUESTION DUE TO THE UNCERTAINTY OF THE
EXACT POSITION OF THE FRONT WED NIGHT THRU THU.
&&
.CLE WATCHES/WARNINGS/ADVISORIES...
OH...NONE.
PA...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...MULLEN
NEAR TERM...KEC/MULLEN
SHORT TERM...MULLEN
LONG TERM...ADAMS
AVIATION...ADAMS
MARINE...ADAMS
AREA FORECAST DISCUSSION
NWS MEMPHIS TN
333 PM CDT SUN AUG 24 2014
.UPDATE...
UPDATED TO EXTEND AFTERNOON RAIN CHANCES TO WEST OF THE MS RIVER.
&&
.PREV DISCUSSION... /ISSUED 232 PM CDT SUN AUG 24 2014/
DISCUSSION...
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...
18Z TAF CYCLE
VFR CONDITIONS WILL PERSIST THROUGH THE NEXT 24 HOURS. WINDS
SHOULD REMAIN LIGHT AND VARIABLE THROUGH THE PERIOD AT 5 KTS OR
LESS. THERE IS A LOW POTENTIAL FOR A STRAY THUNDERSTORM THIS
AFTERNOON OVER NORTHEAST MISSISSIPPI THAT COULD OCCUR NEAR KTUP.
AT THIS TIME...CONFIDENCE REMAINS TOO LOW TO INCLUDE IN THE LATEST
TAF FORECAST. THIS WILL BE MONITORED THROUGH THE DAY AND UPDATES
WILL BE PROVIDED IF NEEDED.
JLH
&&
.MEG WATCHES/WARNINGS/ADVISORIES...
AR...HEAT ADVISORY UNTIL 7 PM CDT MONDAY FOR CLAY-CRAIGHEAD-
CRITTENDEN-CROSS-GREENE-LAWRENCE-LEE AR-MISSISSIPPI-
PHILLIPS-POINSETT-RANDOLPH-ST. FRANCIS.
MO...HEAT ADVISORY UNTIL 7 PM CDT MONDAY FOR DUNKLIN-PEMISCOT.
MS...HEAT ADVISORY UNTIL 7 PM CDT MONDAY 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 MONDAY 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
NWS MEMPHIS TN
232 PM CDT SUN AUG 24 2014
.DISCUSSION...
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...
18Z TAF CYCLE
VFR CONDITIONS WILL PERSIST THROUGH THE NEXT 24 HOURS. WINDS
SHOULD REMAIN LIGHT AND VARIABLE THROUGH THE PERIOD AT 5 KTS OR
LESS. THERE IS A LOW POTENTIAL FOR A STRAY THUNDERSTORM THIS
AFTERNOON OVER NORTHEAST MISSISSIPPI THAT COULD OCCUR NEAR KTUP.
AT THIS TIME...CONFIDENCE REMAINS TOO LOW TO INCLUDE IN THE LATEST
TAF FORECAST. THIS WILL BE MONITORED THROUGH THE DAY AND UPDATES
WILL BE PROVIDED IF NEEDED.
JLH
&&
.MEG WATCHES/WARNINGS/ADVISORIES...
AR...HEAT ADVISORY UNTIL 7 PM CDT MONDAY FOR CLAY-CRAIGHEAD-
CRITTENDEN-CROSS-GREENE-LAWRENCE-LEE AR-MISSISSIPPI-
PHILLIPS-POINSETT-RANDOLPH-ST. FRANCIS.
MO...HEAT ADVISORY UNTIL 7 PM CDT MONDAY FOR DUNKLIN-PEMISCOT.
MS...HEAT ADVISORY UNTIL 7 PM CDT MONDAY 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 MONDAY 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 FORT WORTH TX
931 PM CDT MON AUG 25 2014
.UPDATE...
IT IS ANOTHER QUIET NIGHT ACROSS NORTH AND CENTRAL TEXAS.
ALTHOUGH THE ISOLATED SHOWERS AND THUNDERSTORMS OVER SOUTHEAST
TEXAS...SOUTHEAST OF A CENTER TO LUFKIN LINE...ARE MOVING
NORTHWEST...THEY WILL NOT MAKE IT INTO FORECAST AREA TONIGHT. WE
WILL SEE CLEAR TO PARTLY CLOUDY SKIES WITH LOWS IN THE 70S AREA
WIDE. WITH INCREASED MOISTURE TOMORROW...TEMPERATURES SHOULD BE
AT TO A FEW DEGREES LOWER THAN TODAY. NO CHANGES TO THE FORECAST
ARE PLANNED AT THIS TIME.
58
&&
.AVIATION...
/ISSUED 634 PM CDT MON AUG 25 2014/
/00Z TAFS/
VFR CONDITIONS EXPECTED THROUGH THE PERIOD BUT INCREASING MOISTURE
INTO THE AREA SHOULD LEAD TO SOME SCATTERED SHOWERS AND
THUNDERSTORMS ACROSS NORTH TEXAS BY TUESDAY AFTERNOON. FORECAST
SOUNDINGS ARE NEARLY UNCAPPED TOMORROW AFTERNOON WITH SUFFICIENT
INSTABILITY FOR ISOLATED THUNDERSTORMS ALTHOUGH THERE IS NOT MUCH
IN THE WAY OF FORCING OUTSIDE OF LOCALIZED AREAS OF CONVERGENCE.
THINK THE BEST CHANCE FOR THUNDERSTORMS WILL BE MAINLY SOUTHEAST
OF THE MAJOR METROPLEX AIRPORTS SO HAVE REMOVED THE VCTS FOR DFW
AT THIS TIME AND INCLUDED IT AT WACO BY 21Z. THUNDERSTORMS CHANCES
ARE LIKELY TO INCREASE LATER THIS WEEK.
DUNN
&&
.PREV DISCUSSION... /ISSUED 333 PM CDT MON AUG 25 2014/
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
&&
.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.
&&
$$
91/58
AREA FORECAST DISCUSSION...UPDATED
NWS FORT WORTH TX
634 PM CDT MON AUG 25 2014
.AVIATION...
/00Z TAFS/
VFR CONDITIONS EXPECTED THROUGH THE PERIOD BUT INCREASING MOISTURE
INTO THE AREA SHOULD LEAD TO SOME SCATTERED SHOWERS AND
THUNDERSTORMS ACROSS NORTH TEXAS BY TUESDAY AFTERNOON. FORECAST
SOUNDINGS ARE NEARLY UNCAPPED TOMORROW AFTERNOON WITH SUFFICIENT
INSTABILITY FOR ISOLATED THUNDERSTORMS ALTHOUGH THERE IS NOT MUCH
IN THE WAY OF FORCING OUTSIDE OF LOCALIZED AREAS OF CONVERGENCE.
THINK THE BEST CHANCE FOR THUNDERSTORMS WILL BE MAINLY SOUTHEAST
OF THE MAJOR METROPLEX AIRPORTS SO HAVE REMOVED THE VCTS FOR DFW
AT THIS TIME AND INCLUDED IT AT WACO BY 21Z. THUNDERSTORMS CHANCES
ARE LIKELY TO INCREASE LATER THIS WEEK.
DUNN
&&
.PREV DISCUSSION... /ISSUED 333 PM CDT MON AUG 25 2014/
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
&&
.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.
&&
$$
AREA FORECAST DISCUSSION
NWS LUBBOCK TX
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 / 10 0 10 0 10
&&
.LUB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
93/51
FOR FREQUENTLY ASKED QUESTIONS ABOUT THE AREA FORECAST DISCUSSION
VISIT...
HTTP://WEATHER.GOV/SALTLAKECITY/GENERAL/AFD_FAQS.PHP (ALL LOWER CASE)
AREA FORECAST DISCUSSION
NWS BLACKSBURG VA
110 AM EDT SUN AUG 24 2014
.SYNOPSIS...
HIGH PRESSURE WILL BUILD IN FROM THE GREAT LAKES SUNDAY AND
WEDGE AGAINST THE EASTERN FACE OF THE APPALACHIANS. THIS HIGH
PRESSURE SYSTEM WILL BRING COOLER AND MUCH DRIER AIR TO THE MID
ATLANTIC THROUGH MID WEEK. ANOTHER COLD FRONT WILL APPROACH THE
AREA LATE IN THE WORKWEEK...BRINGING ANOTHER CHANCE OF SHOWERS AND
THUNDERSTORMS.
&&
.NEAR TERM /THROUGH TODAY/...
AS OF 1015 PM EDT SATURDAY...
COVERAGE OF SHOWERS ATTM IS LIMITED...AND MAINLY ISOLATED/WIDELY
SCATTERED. BEST COVERAGE REMAINS ALONG EASTERN SLOPES OF THE BLUE
RIDGE FROM BEDFORD SOUTHWEST TO JUST EAST OF WILKESBORO. THE
LATEST HRRR AND THE RUN FROM 22Z ACTUALLY DID A PRETTY GOOD JOB OF
LINING THIS UP THIS EVENING. THE 00Z NAM/12Z ECMWF APPEAR TOO
BULLISH WITH QPF AND MAY BE SUFFERING FROM CONVECTIVE FEEDBACK AS
THEY CONTINUE TO SHOW 3/4 TO 1.5 INCHES ACROSS PORTIONS OF THE
BLUE RIDGE OVERNIGHT. NOT THAT 3/4" COULD NOT OCCUR...BUT OVERALL
CONVECTIVE TRENDS ARE WEAKER...SO NOT REALLY SEEING ANYTHING MORE
THAN A QUICK QUARTER INCH IN A FEW SPOTS.
FORECAST FAVORS THE HRRR AND WILL KEEP HIGHER THREAT OF SHOWERS
ACROSS THE SRN BLUE RIDGE INTO THE OVERNIGHT WITH LESS COVERAGE
FAR SW VA/SE WV AND OVER THE FAR ERN PIEDMONT.
WEDGE ALREADY TAKING SHAPE PER MESOANALYSIS OF SFC LI FIELDS. LOW
IR SAT ALSO SHOWING EXTENSIVE AREA OF LOWER CIGS MOVING IN FROM
THE NE...AS FAR SW AS THE NEW RIVER VALLEY. WILL SEE CLOUDS
OVERSPREAD THE REST OF THE CWA OVERNIGHT THOUGH THE FAR SW VA AREA
MAY SEE LESS CLOUD COVER. TEMPS WILL STAY UP DUE TO THE CLOUDS IN
THE MID 60S TO LOW 70S.
PREVIOUS VALID DISCUSSION...
SHOWER ACTIVITY WILL BE MORE DIMINISHED ON SUNDAY AS HIGH
PRESSURE CONTINUES TO BUILD IN...CAUSING OUR ATMOSPHERE TO DRY
OUT. BEST CHANCES FOR ANY RAINFALL WILL BE EARLY IN THE DAY...WITH
SHOWERS BECOMING INCREASINGLY ISOLATED DURING THE EVENING FROM
SOUTHWEST TO NORTHEAST. WILL ALSO EXPECT DECREASING CLOUD COVER
DURING THE AFTERNOON AND EVENING AS WELL. HIGH PRESSURE SETTLING
IN WILL RESULT IN COOLER AFTERNOON HIGHS...RANGING FROM THE MID
70S ALONG THE RIDGES TO AROUND 80 ACROSS THE SOUTHSIDE.
&&
.SHORT TERM /TONIGHT THROUGH TUESDAY/...
AS OF 245 PM EDT SATURDAY...
STRONG WEDGE OF HIGH PRESSURE WILL BE OVER THE FORECAST AREA THROUGH
THE PERIOD.
DEEP ENOUGH LAYER OF NORTHEAST WINDS TO BRING A PUSH OF DRIER AIR
INTO THE FORECAST AREA ABOVE 850 MB SUNDAY NIGHT. HOW FAST THE AIR
MASS BELOW 850 MB DRIES OUT WILL BE CRITICAL TO THE EROSION OF LOW
CLOUDS AND ANY LINGERING DRIZZLE AND FOG. BUFKIT SOUNDING SHOW THE
FAR SOUTHWEST PART OF THE COUNTY WARNING AREA MAY NOT BREAK OUT OF
THE CLOUDS UNTIL AFTER 12Z MONDAY. BY MONDAY NIGHT PRECIPITABLE
WATER VALUES DROP BELOW AN INCH FOR THE ENTIRE FORECAST AREA.
&&
.LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/...
AS OF 1145 AM EDT SATURDAY...
ANOTHER UPPER TROF WILL LOWER HEIGHTS MORE OVER THE CENTRAL AND
NORTHERN UNITED STATES WEDNESDAY THROUGH SATURDAY WITH THE UPPER
RIDGE CENTERED OFF THE SOUTHEAST COAST.
AT THE SURFACE HIGH PRESSURE WILL BE OVER THE REGION THROUGH
WEDNESDAY. A FRONT WILL EXTEND FROM A LOW OVER THE MID MISSISSIPPI
VALLEY ACROSS THE OHIO VALLEY INTO THE MID ATLANTIC STATES.
SOUTHWARD PROGRESS OF THIS BOUNDARY WILL BE SLOW. ECMWF AND WPC
GUIDANCE KEEP THIS FRONT NORTH OF THE FORECAST AREA THROUGH FRIDAY.
HAVE TRIMMED BACK THE PROBABILITY OF PRECIPITATION THURSDAY AND
FRIDAY WITH THE FORECAST AREA IN THE WARM SECTOR. A BETTER...MORE
ORGANIZED...CHANCE OF PRECIPITATION WILL BE DURING THE WEEKEND WHEN
THE UPPER TROF AND SURFACE COLD FRONT ARRIVE FROM THE WEST.
EXPECTING GRADUALLY MODERATING TEMPERATURES WEDNESDAY AND THURSDAY.
850 MB TEMPERATURES BY 00Z FRIDAY WILL BE BACK UP IN THE +16 TO +20
RANGE. THIS WILL RESULT IN MAXIMUM TEMPERATURES SLIGHTLY ABOVE
NORMAL.
&&
.AVIATION /06Z SUNDAY THROUGH THURSDAY/...
AS OF 1250 AM EDT SUNDAY...
BANDS OF SHOWERS CONTINUE TO MEANDER ALONG/EAST OF THE BLUE RIDGE
AND WILL LIKELY PERSIST WHILE SLOWLY FADING AND MOVING SOUTH
THROUGH DAYBREAK. THUS WILL NEED TO KEEP A SHRA MENTION EITHER VIA
PREVAILING OR VCSH AT MOST SPOTS EXCLUDING THE SE WVA LOCATIONS
THROUGH EARLY MORNING.
OTRW STILL LOOKING AT THE WEDGE FRONT TO SLOWLY OOZE SW OVERNIGHT
WITH CIGS SINKING TO MVFR THEN IFR/LIFR INTO EARLY SUNDAY
MORNING. MODEL SOUNDING FORECASTS SUGGEST THAT DRIZZLE APPEARS
LIKELY AT MOST TAF SITES LATE TONIGHT AND WILL BE MAINTAINED AT
MOST EASTERN TAF SPOTS FOR NOW. AT THIS TIME...VSBYS SHOULD STAY
ABOVE 1SM...MORE IN THE 2 TO 6 MILE RANGE WHILE CIGS DROP TO UNDER
1K FT WHICH IS ALREADY ONGOING AT KLYH/KROA. KBLF WHICH WILL BE
THE LAST TO SEE THE BOUNDARY SHIFT THROUGH WILL STAY VFR A WHILE
LONGER BUT THEN ALSO DROP TO MVFR AND IFR BY DAWN SUNDAY.
CIGS WILL BE SLOW TO LIFT SUNDAY MORNING BUT THINK BY LATE
MORNING/MIDDAY WILL SEE MAINLY HIGH END MVFR AT ALL SITES...EXCEPT
VFR AT BLF JUST OUTSIDE THE INFLUENCE OF THE WEDGE.
COULD SEE SOME DRIZZLE OR LIGHT RAIN INTO MIDDAY SUNDAY BUT NOT
ENOUGH COVERAGE TO ADD TO THE TERMINALS AT THIS TIME AS DRIER AIR
ALOFT WILL BE WORKING IN FROM THE NE AS WELL.
ANY SHOWERS WILL BEGIN TO WANE SUNDAY AFTERNOON AS HIGH PRESSURE
CONTINUES TO WEDGE INTO THE REGION...BECOMING THE DOMINANT WEATHER
FEATURE.
THIS HIGH PRESSURE STRETCHING FROM NEW ENGLAND SOUTHWARD ALONG
THE EASTERN FACE OF THE APPALACHIANS WILL MAINTAIN DRY CONDITIONS
THROUGH THE EARLY HALF OF THE WORKWEEK. LONG RANGE MODELS INDICATE
THAT A POTENTIAL TROPICAL CYCLONE DEVELOPING NEAR THE BAHAMAS
SHOULD REMAIN OFF THE EAST COAST AND NOT IMPACT THE LOCAL WEATHER.
A COLD FRONT WILL SINK SOUTHWARD FROM THE GREAT LAKES ON
THURSDAY...BRINGING A CHANCE OF SHOWERS AND THUNDERSTORMS AS WELL
AS MVFR/IFR CONDITIONS.
&&
.EQUIPMENT...
AS OF 700 PM SATURDAY...
THE ASOS TEMPERATURE AT LYNCHBURG (LYH) VA REMAINS INOP DUE TO A
BOARD FAILURE. TECHNICIANS ARE EXPECTED TO WORK ON THIS MONDAY. TOWER
OBSERVERS ARE AUGMENTING DURING NORMAL SERVICE HOURS.
&&
.RNK WATCHES/WARNINGS/ADVISORIES...
VA...NONE.
NC...NONE.
WV...NONE.
&&
$$
SYNOPSIS...NF
NEAR TERM...NF/WP
SHORT TERM...AMS
LONG TERM...AMS
AVIATION...JH/NF/RAB/WP
EQUIPMENT...WP
AREA FORECAST DISCUSSION
NWS GREEN BAY WI
1034 PM CDT MON AUG 25 2014
UPDATED AVIATION PORTION FOR 06Z TAF 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 06Z TAF ISSUANCE
ISSUED AT 1022 PM CDT MON AUG 25 2014
VFR CONDITIONS WILL CONTINUE THROUGH TUESDAY EVENING. ONLY
SIGNIFICANT CHANGE TO THE 06Z TAFS IS TO ADD A BROKEN DECK
AROUND 4500 FEET OVERNIGHT AT KRHI. CLOUDY SHIELD APPROACHING
NORTH CENTRAL WISCONSIN LATE THIS EVENING AND COULD MOVE OVER
THIS SITE. AFTER 16Z TUESDAY...SOME GUSTS TO AROUND 14 KNOTS
CAN BE EXPECTED FROM THE WEST/NORTHWEST. STILL MUCH DEBATE IN
WHEN LAKE BREEZE WILL ARRIVE AT KMTW. STILL HAVE 22Z FOR NOW...
BUT LATER SHIFTS MAY NEED TO ADJUST TIMING LATER TUESDAY MORNING.
&&
.GRB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM.....MPC
LONG TERM......TE
AVIATION.......ECKBERG
AREA FORECAST DISCUSSION
NWS GREEN BAY WI
701 PM CDT MON AUG 25 2014
UPDATED AVIATION PORTION FOR 00Z TAF 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 00Z TAF ISSUANCE
ISSUED AT 657 PM CDT MON AUG 25 2014
VFR CONDITIONS WILL PREVAIL TONIGHT AND TUESDAY ACROSS THE REGION AS
HIGH PRESSURE DOMINATES THE REGION. SOUTH/SOUTHWEST WINDS WILL VEER
WEST AND THEN WEST OR NORTHWEST OVERNIGHT THROUGH MUCH OF TUESDAY.
MAIN QUESTION AT THE KMTW SITE IS WHEN A LAKE BREEZE WILL KICK IN.
HAVE FIGURED 22Z FOR NOW THINKING GRADIENT WINDS MAY DELAY SHIFT
TO THE SOUTHEAST...HOWEVER CONFIDENCE IS LOW ON THE TIMING OF THIS
EVENING.
&&
.GRB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM.....MPC
LONG TERM......TE
AVIATION.......ECKBERG
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
620 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 00Z TAFS THROUGH 00Z TUESDAY EVENING)
ISSUED AT 620 PM CDT MON AUG 25 2014
WITH A COLD FRONT MOVING THROUGH THE REGION AND HIGH PRESSURE
PUSHING DOWN FROM THE NORTHWEST...QUIET CONDITIONS ARE EXPECTED AT
THE TAF SITES WITH WINDS STAYING OUT OF THE WEST AND STAYING LIGHT
THROUGHOUT. CLOUD COVER WILL VARY AT TIMES...BUT WILL ALL BE VFR
AT OVER 8KFT THROUGH TOMORROW AFTERNOON.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...04
LONG TERM...04
AVIATION...HALBACH
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
600 PM CDT SUN AUG 24 2014
.UPDATE...
ISSUED AT 600 PM CDT SUN AUG 24 2014
MONITORING CONVECTIVE TRENDS ACROSS THE REGION...WITH A
PARTICULAR FOCUS ON SOUTHEAST MINNESOTA INTO THE EARLY EVENING
HOURS. THE 24.22Z RAP ANALYSIS SHOWS A VERY UNSTABLE AIR MASS IS
CENTERED ALONG THE MISSISSIPPI RIVER WITH UPWARDS OF 3000-5000
J/KG OF SURFACE BASED CAPE NOSING UP TOWARD THE TWIN CITIES.
HOWEVER...THIS AIR MASS APPEARS TO BE CAPPED OFF DUE TO THE LACK
OF A CUMULUS FIELD ACROSS SE MN/NE IA/W WI. ALSO...DEEP WIND SHEAR
IS ALSO VERY LACKING THIS FAR SOUTH...SO WHILE SOME CONVECTION HAS
INITIATED ACROSS NC IA/SC MN...IT HAS BEEN VERY PULSEY AND CAN NOT
MAINTAIN ITSELF FOR VERY LONG. FURTHER NORTH WHERE THERE IS DEEPER
WIND SHEAR AND BETTER CONVERGENCE IN THE SURFACE FEATURES...STORMS
ARE QUICKLY GOING SEVERE. WHILE THERE WILL BE ABOUT A 2-3 HOUR
PERIOD FROM NOW THROUGH 9 PM WHERE THIS CONVECTION WILL COME
THROUGH MOWER/DODGE/OLMSTED COUNTIES...EXPECTING THAT IT WILL STAY
UNORGANIZED AND NOT SEVERE. SOME OF THIS CONVECTION COULD MAKE IT
INTO ROCHESTER AROUND 7PM...BUT THE NORTHERN EDGE OF THE CAP
APPEARS TO BE AT OR JUST TO THE NORTH OF THE CITY...WHICH WOULD
HELP TO KEEP THEM DRY THIS EVENING. BEYOND THIS...THERE APPEARS TO
BE A SECOND WAVE OF CONVECTION POSSIBLE OVERNIGHT AS THE MAIN
TROUGH/SURFACE COLD FRONT APPROACH FROM THE WEST. INSTABILITY
REMAINS HIGH OVERNIGHT...BUT THE OVERALL SHEAR IS LACKING WHICH
SHOULD KEEP THIS CONVECTION UN-ORGANIZED AND MAINLY NOT SEVERE.
&&
.SHORT TERM...(THIS EVENING THROUGH TUESDAY NIGHT)
ISSUED AT 304 PM CDT SUN AUG 24 2014
THE MAIN CONCERN IS WITH THE RAIN CHANCES THROUGH THE PERIOD.
SURFACE ANALYSIS THIS AFTERNOON SHOWS AN AREA OF LOW PRESSURE OVER
NORTH DAKOTA WITH A COLD FRONT TRAILING SOUTH THROUGH WESTERN
MINNESOTA INTO NEBRASKA. WATER VAPOR IMAGERY SHOWS A WOUND UP
UPPER LEVEL LOW OVER EASTERN MONTANA THAT WAS LIFTING TO THE
NORTHEAST.
THE 24.12Z MODELS ARE ALL IN REASONABLY GOOD AGREEMENT WITH THE
HANDLING OF THE UPPER LEVEL SYSTEM. IT WILL CONTINUE TO MOVE
NORTHEAST REACHING WESTERN ONTARIO BY MONDAY EVENING. THE MAIN
SHORT WAVE TROUGH WITH THIS SYSTEM IS VERY NEAR THE UPPER LEVEL
LOW AND IS EXPECTED TO REMAIN THAT WAY. THIS TAKES THE PV
ADVECTION IN THE 500-300 MB LAYER FROM EASTERN NORTH DAKOTA ACROSS
NORTHWEST MINNESOTA INTO ONTARIO. THIS WILL TAKE THE BULK OF THE
UPPER LEVEL FORCING WELL NORTH OF THE REGION BUT SOME UPPER LEVEL
DIVERGENCE SHOULD SPREAD ACROSS THE AREA TONIGHT AS THE RIGHT
ENTRANCE REGION OF THE UPPER LEVEL JET MOVES OVER. AS THE FRONT
MOVES IN TONIGHT...SOME WEAK FRONTOGENESIS SHOULD OCCUR IN THE
850-500 MB LAYER. GOOD LOW LEVEL WARM AIR ADVECTION AHEAD OF THE
FRONT WILL HELP TO GENERATE 4 TO 6 UBAR/S OF UP GLIDE ON THE 310K
ISENTROPIC SURFACE WITH THE MOISTURE TRANSPORT ON THIS SURFACE
EXPECTED TO BE INTO THE AREA FROM LATE EVENING THROUGH THE
OVERNIGHT HOURS. THE 24.12Z SOUNDING FROM KMPX SHOWS A STRONG CAP
IS IN PLACE BETWEEN 850 AND 700 MB AND THE CONCERN BECOMES WHETHER
THE FORCING WILL BE STRONG ENOUGH TO BREAK THE CAP. THE 24.12Z NAM
BUFKIT SOUNDINGS SUGGEST THAT THE CAP MAY WEAKEN BUT NOT TOTALLY
BREAK AND THIS IS REFLECTED IN THE MODEL ONLY PRODUCING SOME
SCATTERED ACTIVITY ALONG THE FRONT AS IT COMES THROUGH. THE
24.12Z GFS AND ECMWF SHOW MUCH MORE QPF ALONG THE FRONT SUGGESTING
THE CAP WILL BREAK. THE SHORT TERM MESO-MODELS ARE ABOUT AS
EQUALLY SPLIT. THE 24.12Z HI-RES ARW LOOKS TO HOLD THE CAP IN
PLACE WITH ALMOST NO ACTIVITY OVER THE AREA...WHILE THE HI-RES NMM
IS CLOSER TO THE NAM WITH JUST SOME SCATTERED ACTIVITY. THE 24.12Z
SPC WRF LOOKS TO DISSIPATE THE CAP AS EARLY AS LATE THIS AFTERNOON
WITH LOTS OF CONVECTION DEVELOPING ACROSS MINNESOTA AND MOVING
ACROSS THE AREA IN THE NIGHT. OUTPUT FROM THE 24.12Z HOP WRF IS
ALSO SPLIT WITH A COUPLE OF MEMBERS DEVELOPING LOTS OF CONVECTION
AND THE OTHER TWO STAYING WITH JUST SCATTERED ACTIVITY. IF THE CAP
WOULD BREAK...THE BEST CHANCE FOR THIS TO OCCUR WOULD BE ACROSS
THE NORTHERN SECTIONS OF THE FORECAST AREA CLOSER TO THE DYNAMIC
FORCING AND WILL MAINTAIN THE LIKELY RAIN CHANCES ACROSS THAT AREA
WHILE TAPERING DOWN TO 30 TO 40 PERCENT CHANCE ACROSS THE SOUTH.
SOME THREAT OF SEVERE ACROSS THE NORTH AS WELL IF THE CAP CAN
BREAK. PLENTY OF INSTABILITY WILL REMAIN IN PLACE AHEAD OF THE
FRONT WITH THE NAM SHOWING 1000-1500 J/KG OF ML CAPE ALONG WITH 40
KNOTS OF 0-3KM SHEAR. DAMAGING WINDS AND HEAVY RAIN SHOULD BE THE
MAIN THREATS AS WARM CLOUD DEPTHS WILL REMAIN IN THE 3.5 TO 4 KM
RANGE AHEAD OF THE FRONT. MAY ALSO HAVE TO AWARE OF A SPIN UP
TORNADO THREAT AS A DIFFERENTIAL HEATING BOUNDARY IS IN PLACE ON
THE CLOUD EDGE. IF THIS BOUNDARY MAINTAINS ITSELF INTO THE
EVENING...THE NAM INDICATES THE 0-1KM SHEAR WILL INCREASE TO
AROUND 25 KNOTS.
THE FRONT SHOULD THEN PASS THROUGH THE AREA MONDAY WITH THE
POSSIBILITY OF SOME SCATTERED ACTIVITY ALONG IT. NOT MUCH FORCING
ALONG THE FRONT BUT COULD SEE A DIURNAL INCREASE IN THE ACTIVITY
DURING THE AFTERNOON WHEN THE ML CAPE SHOULD AGAIN BE IN THE
2000-3000 J/KG RANGE.
THE MODELS THEN HAVE REALLY TRENDED TOWARD PUSHING THIS FRONT
FARTHER SOUTH FROM MONDAY NIGHT INTO TUESDAY NIGHT AS THE HIGH
PRESSURE BUILDING IN BEHIND IT IS MUCH STRONGER. MODELS CONTINUE
TO SHOW A SHORT WAVE TROUGH MOVING ALONG THE UPPER LEVEL RIDGE
AXIS AND INTERACTING WITH THE FRONT. IF THE FRONT DOES PUSH AS FAR
SOUTH AS THE MODELS ARE CURRENTLY INDICATING...THIS WOULD PLACE
THE HIGHEST RAIN CHANCES SOUTH OF THE IOWA/MINNESOTA BORDER. WILL
MAINTAIN SOME 50 TO 60 PERCENT CHANCES FROM MONDAY NIGHT INTO
TUESDAY NIGHT...BUT LIMIT THEM TO THE SOUTHERN SECTIONS.
.LONG TERM...(WEDNESDAY THROUGH SUNDAY)
ISSUED AT 304 PM CDT SUN AUG 24 2014
THE FRONT IS EXPECTED TO STILL NOT BE TOO FAR SOUTH OF THE AREA
BY THE MIDDLE OF THE WEEK. THE 24.12Z ECMWF AND GFS IN DECENT
AGREEMENT OF BRINGING ANOTHER SHORT WAVE TROUGH ACROSS THE TOP OF
THE RIDGE AXIS WITH A SURFACE LOW MOVING ALONG THE FRONT. BASED ON
THIS...WILL HAVE UP TO 50 PERCENT CHANCES ACROSS THE SOUTH FROM
WEDNESDAY INTO THURSDAY NIGHT. THE RAIN CHANCES SHOULD THEN
DIMINISH TO CLOSE OUT THE WEEK INTO THE WEEKEND AS HIGH PRESSURE
BUILDS IN BEHIND THE MID WEEK SYSTEM.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON)
ISSUED AT 1221 PM CDT SUN AUG 24 2014
VISIBLE SATELLITE SHOWING STRATUS MIXING OUT NICELY FROM WEST TO
EAST AS INCREASING SOUTHERLY FLOW/DAYTIME HEATING SCOURS OUT THE
LOWER BOUNDARY LAYER. LOOK FOR VFR CONDITIONS GOING INTO THE
AFTERNOON HOURS WITH SOUTH WINDS IN THE 10-20KT RANGE. A FEW
HIGHER GUST AROUND 25KT CAN BE EXPECTED AT KRST.
A COLD FRONT WILL THEN PUSH INTO THE AREA LATER THIS
EVENING...SPARKING OFF A LINE OF SHRA/TSRA. MODELS IN PRETTY GOOD
AGREEMENT THAT THE SOUTHERN END OF THIS LINE OF SHRA/TS WILL
BEGIN AFFECTING KRST AROUND 03-04Z AND KLSE 05-06Z. PLAN ON A FEW
HOUR WINDOW OF SHRA/TSRA ACTIVITY. LOOKS LIKE CIGS SHOULD STAY IN
THE VFR RANGE WITH VIS POSSIBLY DIPPING INTO MVFR FOR A LITTLE
BIT IN TSRA/BR. MODELS INDICATING A BAND OF STRATUS WITH THE
PASSAGE OF THE COLD FRONT IN THE 13-18Z TIMEFRAME. NOT CONFIDENT
YET AT THIS POINT IF THIS WILL CONSTITUTE A CEILING OR NOT. WILL
KEEP AN EYE ON IT.
&&
.HYDROLOGY...
ISSUED AT 304 PM CDT SUN AUG 24 2014
HEAVY RAIN WILL BE A THREAT WITH ANY STORMS THAT DEVELOP TONIGHT.
WARM CLOUD DEPTHS WILL BE IN THE 3.5 TO 4 KM RANGE WITH
PRECIPITABLE WATERS APPROACHING TWO INCHES. THE CONCERN FOR HEAVY
RAIN AND POSSIBLE FLOODING WITH THE STALLED FRONT FOR THE EARLY
PART OF THE WEEK ARE DIMINISHING WITH THE FRONT EXPECTED TO PUSH
FARTHER SOUTH. THE HIGHEST AXIS OF PRECIPITABLE WATERS SHOULD LAY
UP SOUTH OF THE FRONT ACROSS SOUTHERN IOWA/NORTHERN MISSOURI INTO
ILLINOIS.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
UPDATE...HALBACH
SHORT TERM...04
LONG TERM...04
AVIATION...DAS
HYDROLOGY...04
FORECAST DISCUSSION FOR ROUTINE AFTERNOON FORECAST 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 18Z TAF ISSUANCE
ISSUED AT 1148 AM CDT SUN AUG 24 2014
POCKET OF IFR CIGS AND VSBYS OVER NORTH-CENTRAL
WISCONSIN WILL RETURN TO MVFR THIS AFTERNOON AS DAYTIME HEATING
MIXES OUT SOME OF THE LOW LEVEL MOISTURE. THIS WILL BE A SLOW
PROCESS MOST AREAS HAVE A CHANCE TO SEE VFR LATE THIS AFTERNOON INTO
EARLY THIS EVENING. THEN A WEAK FRONT WILL SLOW ITS FORWARD
PROGRESS AS IT MOVES INTO THE REGION TONIGHT AND HANGS AROUND ON
MONDAY. THE FRONT IS EXPECTED TO BRING A BROKEN LINE OF SHOWERS AND
THUNDERSTORMS TO CENTRAL AND NORTH-CENTRAL WISCONSIN AFTER
MIDNIGHT...BUT THE LINE SHOULD BE WEAKENING AS IT MOVES EAST INTO
NORTHEAST WISCONSIN. AS A RESULT...LEFT ANY MENTION OF
PRECIPITATION OUT OF THE FOX VALLEY AND LAKESHORE TAF SITES. AREAS
OF LOW CLOUDS AND FOG WILL ALSO LIKELY REDEVELOP LATER TONIGHT.
BETTER FLYING CONDITIONS WILL RETURN ON MONDAY.
&&
.GRB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM.....MPC
LONG TERM......TE
AVIATION.......MPC
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
1221 PM CDT SUN AUG 24 2014
.UPDATE...
ISSUED AT 1221 PM CDT SUN AUG 24 2014
VISIBLE SATELLITE SHOWING STRATUS ERODING FROM WEST TO EAST ACROSS
THE FORECAST AREA AS SOUTHERLY FLOW INCREASES AND DAYTIME HEATING MIXES
OUT THE LOWER BOUNDARY LAYER MOISTURE. RAP SHOWING AXIS OF 26-30C
AIR NOSING INTO THE AREA THIS AFTERNOON IN ADVANCE OF A COLD FRONT
PUSHING INTO CENTRAL MN/WESTERN IA. WILL HOLD STEADY ON HIGHS
TOPPING OFF IN THE MIDDLE 80S ACROSS CENTRAL WISCONSIN AND UPPER
80S/AROUND 90 ALONG AND WEST OF THE MISSISSIPPI RIVER. WITH DEW
POINTS IN THE 70S...PLAN ON MAXIMUM HEAT INDICES IN THE 95-100
DEGREE RANGE IN THE 2-6PM TIME FRAME.
&&
.SHORT TERM...(TODAY THROUGH TONIGHT)
ISSUED AT 230 AM CDT SUN AUG 24 2014
HOT AND HUMID TODAY. 850 MB SREF TEMP ANOMALIES PEGGING +1.5 TODAY
WHILE 925 MB TEMPS RANGE FROM 26-28 C. HIGHS SHOULD REACH 90 FOR
MANY LOCATIONS. MEANWHILE...SFC DEWPOINTS WILL LIKELY HOLD IN THE
LOW 70S THROUGH THE DAY. THE MIX OF HOT/HUMID AIR WILL PLACE HEAT
INDICES AROUND 100 DEGREES FOR MUCH OF THE FORECAST AREA THIS
AFTERNOON. HOWEVER...SOME UNCERTAINTY TO HOW MUCH CLOUD COVER WILL
BE AROUND TODAY. LOW STRATUS COULD LINGER ACROSS WESTER/CENTRAL WI
THROUGH THE MORNING...WHILE SOME HIGH CLOUDS START TO TRACK INTO
AREAS WEST OF THE RIVER THIS AFTERNOON. ALL WOULD TEMPER TEMPS BACK
A FEW DEGREES...AND THUS DROP THE HEAT INDICES DOWN. AT THIS
TIME...DON/T FEEL A HEAT ADVISORY WILL BE NEEDED. IF TEMPS WARM A
DEGREE OR TWO MORE THAN EXPECTED...ONE MAY BE NECESSARY.
TONIGHT...AN UPPER LEVEL SHORTWAVE TROUGH WILL LIFT NORTHEAST ACROSS
THE NORTHERN PLAINS AND INTO SOUTHERN CANADA. AN ASSOCIATED COLD
FRONT WILL LEAD WELL AHEAD OF THE TROUGH...MOVING INTO WESTERN WI
TOWARD 06Z. A RIBBON OF LOW LEVEL MOISTURE WILL RUN AHEAD OF THE
FRONT...WITH MUCAPES FROM 1-2K J/KG. PLENTY OF FUEL FOR THE BOUNDARY
TO FIRE SHOWERS/STORMS. THE DEEPER SHEAR IS WEST OF THE INSTABILITY
AXIS...BUT ENOUGH 0-3KM SHEAR THAT SOME STORM ORGANIZATION COULD
OCCUR AND POTENTIALLY A STRONG WIND THREAT. MOSTLY...HEAVY RAIN AND
LARGE HAIL WOULD BE THE MAIN THREATS.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 230 AM CDT SUN AUG 23 2014
NAM/GFS/ECMWF CONTINUE TO POINT TO THE SAME SOLUTION THEY HAVE BEEN
SUGGESTING FOR THE PAST FEW DAYS...ONE THAT WILL BRING ROUNDS OF
PCPN WITH THE POTENTIAL FOR HEAVY RAIN AND STRONGER STORMS.
SEVERAL FACTORS WILL PLAY ROLES IN THE PRECIPITATION CHANCES OVER
THE NEXT FEW DAYS.
1) COLD FRONT. THE COLD FRONT THAT TRACKS ACROSS THE REGION LATE
TONIGHT WILL GRADUALLY ORIENTATE ITSELF AS A WEST-EAST STATIONARY
FRONT ACROSS CENTRAL IA-NORTHERN ILL FOR THE FIRST HALF OF THE NEW
WORK WEEK. ESSENTIAL...IT GETS STUCK UNDER THE BROAD UPPER LEVEL
RIDGE...AND IS NOT EXPECTED TO GET A NUDGE OUT OF THE REGION UNTIL
LATER ON THU WHEN A SHORTWAVE TROUGH DRIVES EASTWARD ACROSS THE MID
MISSISSIPPI RIVER VALLEY.
WHERE THE FRONT RESTS WILL BE THE MAIN REGION FOR STORM DEVELOPMENT.
2) LOW LEVEL JET/MOISTURE TRANSPORT. MODELS POINT TO THE NOSE OF THE
850 MB JET AND MOISTURE TRANSPORT FOCUSING INTO WESTERN/SOUTHERN IA
MON-THU NIGHTS...IMPINGING ON AND ACROSS THE STATIONARY FRONT. NIGHT
TIME MCS/S ARE LIKELY IN THIS REGION ALL THESE NIGHTS...TRACKING
EAST OVERNIGHT. ASSOCIATED MCVS WILL LIKELY BE ANOTHER SOURCE FOR
FORCING.
3) INSTABILITY. NAM AND GFS BUILD UPWARDS OF 4000+ J/KG OF SBCAPE
ALONG AND SOUTH OF THE BOUNDARY. ELEVATED INSTABILITY DOES SLOPE
NORTH ACROSS THE BOUNDARY. FOR THE FORECAST AREA...THE BULK OF THE
INSTABILITY WOULD STAY SOUTH...BUT ENOUGH IN THE VICINITY TO SUPPORT
STORM DEVELOPMENT.
4) WIND SHEAR. THE DEEPER-STRONGER SHEAR IS EXPECTED TO LIE WELL
NORTH OF THE STATIONARY FRONT...IN THE COLDER AIR. THERE COULD BE
ENOUGH OVERLAP OF FAVORABLE SHEAR INTO THE INSTABILITY AXIS TO
FURTHER SUPPORT STORM DEVELOPMENT AND UPDRAFTS. STABLE SFC LAYER
NORTH OF THE FRONT WILL INHIBIT THE GUST POTENTIAL...BUT WON/T
COMPLETELY RULE IT OUT. ALONG AND SOUTH OF THE FRONT THE STRONG WIND
POTENTIAL INCREASES. HEAVY RAIN WILL OCCUR. HAIL WILL BE POSSIBLE
BOTH SIDES OF THE BOUNDARY.
WITH SEVERAL FACTORS FAVORING HEAVY RAIN...ALONG WITH DAILY/NIGHTLY
CHANCES FOR STORMS...THE HYDRO CONCERNS ARE INCREASING. MORE ON THE
THREAT FOR RIVER AND FLASH FLOOD IMPACTS IN THE HYDRO SECTION BELOW.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON)
ISSUED AT 1221 PM CDT SUN AUG 24 2014
VISIBLE SATELLITE SHOWING STRATUS MIXING OUT NICELY FROM WEST TO
EAST AS INCREASING SOUTHERLY FLOW/DAYTIME HEATING SCOURS OUT THE
LOWER BOUNDARY LAYER. LOOK FOR VFR CONDITIONS GOING INTO THE
AFTERNOON HOURS WITH SOUTH WINDS IN THE 10-20KT RANGE. A FEW
HIGHER GUST AROUND 25KT CAN BE EXPECTED AT KRST.
A COLD FRONT WILL THEN PUSH INTO THE AREA LATER THIS
EVENING...SPARKING OFF A LINE OF SHRA/TSRA. MODELS IN PRETTY GOOD
AGREEMENT THAT THE SOUTHERN END OF THIS LINE OF SHRA/TS WILL
BEGIN AFFECTING KRST AROUND 03-04Z AND KLSE 05-06Z. PLAN ON A FEW
HOUR WINDOW OF SHRA/TSRA ACTIVITY. LOOKS LIKE CIGS SHOULD STAY IN
THE VFR RANGE WITH VIS POSSIBLY DIPPING INTO MVFR FOR A LITTLE
BIT IN TSRA/BR. MODELS INDICATING A BAND OF STRATUS WITH THE
PASSAGE OF THE COLD FRONT IN THE 13-18Z TIMEFRAME. NOT CONFIDENT
YET AT THIS POINT IF THIS WILL CONSTITUTE A CEILING OR NOT. WILL
KEEP AN EYE ON IT.
&&
.HYDROLOGY...
ISSUED AT 230 AM CDT SUN AUG 23 2014
WARM CLOUD DEPTHS CONTINUE TO APPROACH 4 KFT ALONG AND SOUTH OF THE
FRONT WITH PWS UPWARDS OF 1.5 - 1.75 INCHES. STORMS IN THIS
ENVIRONMENT WILL BE EFFICIENT RAIN PRODUCERS...AND HEAVY RAIN WILL BE
LIKELY WITH ANY STRONGER STORM.
STORM TRACKS LOOKS MOSTLY EAST ALONG AND AROUND THE FRONT...FAVORING
TRAINING THUNDERSTORMS AND REPEATED ROUNDS OF SOAKING RAINS. THERE
COULD BE IMPACTS TO RIVER SYSTEMS IF MCS/S IMPACT THE SAME AREAS
NIGHT AFTER NIGHT. THE FLASH FLOOD THREAT WOULD ALSO INCREASE AS
GROUNDS BECOME SATURATED.
OVERALL - CURRENT MODEL SOLUTIONS WOULD KEEP THE BULK OF THE
POTENTIAL HYDRO ISSUES SOUTH OF I-90...MOSTLY NORTHEAST IA AND
SOUTHWEST WI.
A HYDROLOGIC OUTLOOK MIGHT BE NEEDED IN THE NEXT COUPLE DAYS TO
FURTHER OUTLINE THE RAINFALL-RIVER THREATS. WOULD NOT BE SURPRISED
IF FLASH FLOOD WATCHES EVENTUALLY BECOME NECESSARY LATER IN THE
WEEK.
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
UPDATE...DAS
SHORT TERM...RIECK
LONG TERM....RIECK
AVIATION...DAS
HYDROLOGY....RIECK
SOUTHWEST CALIFORNIA AREA FORECAST DISCUSSION
NWS LOS ANGELES/OXNARD CA
1100 PM PDT MON AUG 25 2014
NEW AVIATION DISCUSSION
.SYNOPSIS...
SLIGHTLY BELOW NORMAL DAYTIME HIGHS ARE EXPECTED AGAIN ON TUESDAY
WITH A TROUGH OF LOW PRESSURE OVERHEAD. A SIGNIFICANT WARM UP IS
EXPECTED FOR THE SECOND HALF OF THE WEEK AS A RIDGE OF HIGH
PRESSURE DEVELOPS. THE HIGH PRESSURE WILL ALSO RESULT IN A
SHRINKING OF THE MARINE LAYER AND LESS NIGHT THROUGH MORNING LOW
CLOUD COVERAGE. A COOLING TREND IS THEN LIKELY INTO EARLY NEXT
WEEK.
&&
.UPDATE...
ONSHORE FLOW IS WEAKENING THIS EVENING EVEN AS TROUGH APPROACHES
THE AREA. WATER VAPOR IMAGERY INDICATES A TROUGH OF LOW PRESSURE
CONTINUING TO DIG INTO THE GREAT BASIN THIS EVENING. A DECENT
CLOUD SHIELD CAN BE SEEN OVER THE SAN JOAQUIN VALLEY ASSOCIATED
WITH THE TROUGH. HOWEVER...THE TROUGH IS DOING BATTLE WITH A
STRONG RIDGE OF HIGH PRESSURE OVER THE BIG BEND OF TEXAS. MODEL
SOLUTIONS ALL SUGGEST THE HIGH PRESSURE SYSTEM WINNING OUT. WITH
WEAKENING ONSHORE FLOW...THE MARINE LAYER DEPTH CONTINUES TO THIN
WITH THE LATEST AMDAR SOUNDINGS FROM KLAX INDICATING A DEPTH
AROUND 1100 FEET THIS EVENING. WITH LESS ONSHORE FLOW AND A
THINNER MARINE LAYER...A SLIGHT WARM UP SHOULD OCCUR ON TUESDAY.
THE CURRENT PACKAGE ADDRESS THE WARMING FOR TUESDAY REASONABLY.
AS THE TROUGH BRUSHES THE AREA...SOME MIDDLE AND HIGH LEVEL CLOUDS
WILL LIKELY RESULT. 13-KM RAP MODEL SOLUTIONS SUGGEST A NARROW
WINDOW FOR CONVECTIVE STORMS ON TUESDAY OVER THE EASTERN SAN
GABRIEL RANGE...BUT ALL OTHER MODEL SOLUTIONS KEEP THE CONVECTIVE
POTENTIAL TO THE EAST OF THE AREA. SOME CLOUDS HAVE BEEN ADDED FOR
THE SAN GABRIEL RANGE. WITH CONFIDENCE LOW IN THE MODEL SOLUTIONS
AT THIS TIME...NO MENTION OF CONVECTIVE SHOWERS WAS ADDED FOR THE
EASTERN SAN GABRIEL RANGE FOR TUESDAY.
&&
.PREV DISCUSSION...
SHORT TERM...ONSHORE PRESSURE WEAKEN FURTHER INTO WEDNESDAY...AND
HOLD COURSE ON THURSDAY. AS A RESULT...WE SHOULD SEE A MORE
NOTICEABLE WARMUP ON WEDNESDAY AND THURSDAY AS THE RIDGE PEAKS.
BY WEDNESDAY AND THURSDAY...THE INVERSION WILL STRENGTHEN WHICH
SHOULD KEEP CLOUDS OUT OF THE VALLEYS AND MAY EVEN KEEP CLOUDS OFF
SOME OF THE COASTS. CURRENT COASTAL TEMPERATURE FORECASTS ARE
CONSERVATIVE FACTORING IN THE MARINE LAYER UNCERTAINTY...AND
TEMPERATURES MAY END UP A FEW DEGREES HIGHER IF STRATUS INDEED
STAYS AWAY. DENSE FOG MAY BE A CONCERN AS WELL.
THE OTHER WRINKLE IS INCREASING NORTHWEST FLOW THURSDAY AND THURSDAY
NIGHT. AT THIS POINT EXPECTING A NEAR ADVISORY SUNDOWNER OVER SBA
COUNTY. THIS SHOULD KEEP CLOUDS OUT OF SRN SBA AND VENTURA
COUNTY...AND REALLY HEAT UP THE SOUTH COAST...MAYBE EVEN APPROACHING
HIGH TEMPERATURE RECORDS. IF A COASTAL EDDY ENDS UP FORMING FROM
THIS...LA COUNTY COULD SEE SOME COOLING STRATUS FORM.
FOR UP COMING SURF EVENT...SEE BEACHES SECTION BELOW.
LONG TERM...NOT A WHOLE LOT OF CHANGE FROM THURSDAY INTO FRIDAY.
CONTINUED WARM AND ABOVE NORMAL TEMPERATURES WITH A SHALLOW MARINE
LAYER AND LIMITED STRATUS...AS THE RIDGE ALOFT REMAINS OVER
SOUTHERN CALIFORNIA. A SLIGHTLY STRONGER SUNDOWNER IS EXPECTED ON
FRIDAY AND SHOULD APPROACH WIND ADVISORY STRENGTH.
EXTENDED MODELS ARE SHOWING A BROAD TROUGH FORMING OVER THE
NORTHWEST STATES...WHICH WOULD PUSH THE RIDGE TOWARD THE SOUTHEAST.
MODERATELY CONFIDENT OF A COOLING TREND WITH INCREASING ONSHORE FLOW
EARLY NEXT WEEK...BUT THERE IS SOME DISCREPANCIES AS TO HOW MUCH THE
RIDGE MOVES AWAY AND THEREFORE HOW STRONG THAT TREND ENDS UP BEING.
CURRENT FORECAST IS WEIGHTED TOWARD THE BETTER PERFORMING AND COOLER
GFS SOLUTION...BUT DID TEMPER THE COOLING SOME FROM THE PREVIOUS
FORECASTS.
&&
.AVIATION...
26/0600Z
LOW CONFIDENCE IN TAFS FOR KLAX...KLGB...KOXR...KSBA AND KPRB. THERE
IS A 40 PERCENT CHANCE THAT CIGS WILL NOT DEVELOP. ARRIVAL TIMES ARE
ALSO SUSPECT. LOW CONFIDENCE IN EXACT ARRIVAL TIMES FOR KSMX AND
KSBP BUT CIGS SHOULD BE IN PLACE BY 13Z. BETTER CONFIDENCE IN BURN
OFF TIMES.
KLAX...LOW CONFIDENCE IN TAF WITH A 40 PERCENT CHANCE OF NO CIGS AT
ALL. CIGS COULD ARRIVE ANY TIME BETWEEN 10Z AND 13Z. IF CIGS DO
ARRIVE THERE IS A 30 PERCENT CHC OF A 17Z BURN OFF.
KBUR...HIGH CONFIDENCE IN CAVU TAF.
&&
.MARINE...
25/900 PM.
SMALL CRAFT ADVISORY CONDITIONS FOR HAZARDOUS SEAS MAY DEVELOP
TUESDAY NIGHT SOUTH OF POINT CONCEPTION AND PERSIST THROUGH
WEDNESDAY AS SWELLS FROM HURRICANE MARIE MOVE ACROSS THE AREA.
ALSO...SMALL CRAFT CONDITIONS FOR WINDS ARE POSSIBLE EACH AFTERNOON
THURSDAY THROUGH SATURDAY IN THE VICINITY OF POINT CONCEPTION AND
THE NORTHERN CHANNEL ISLANDS WITH GUST TO 30 KNOTS.
&&
.BEACHES...
25/900 PM.
HIGH SURF ADVISORY FOR EXPOSED SOUTH FACING SHORES SOUTH OF POINT
CONCEPTION REMAINS IN EFFECT FROM TUESDAY THROUGH FRIDAY
CONTINUES. HURRICANE MARIE SWELL`S WILL IMPACT THE EXPOSED SOUTH
FACING SHORES NORTH OF POINT CONCEPTION AS WELL AND A HIGH RIP
CURRENT RISK IS EXPECTED. THE CONFIDENCE IS RELATIVELY HIGH AS
MARIE WILL REMAIN A HURRICANE THROUGH TUESDAY EVENING. MARIE IS
EXPECTED TO REMAIN A MAJOR HURRICANE WHILE THE FETCH SHIFTS TO
160-190 DEGREES THROUGH EARLY TUESDAY. AN EXTRATROPICAL STORM IN
THE SOUTHERN HEMISPHERE IS EXPECTED TO STRENGTHEN WITH STORM FORCE
WINDS WITHIN 190-210 DEGREES RELATIVE SOUTHERN CALIFORNIA THIS
WEDNESDAY. THE SWELLS GENERATED ARE EXPECTED TO ARRIVE NEXT WEEK
THURSDAY INTO FRIDAY. PLEASE SEE THE LATEST LAXCFWLOX FOR CURRENT
EVENT DETAILS.
&&
.LOX WATCHES/WARNINGS/ADVISORIES...
HIGH SURF ADVISORY (SEE LAXCFWLOX).
BEACH HAZARDS STATEMENT (SEE LAXCFWLOX).
HIGH RIP CURRENT RISK (SEE LAXSRFLOX).
&&
$$
PUBLIC...HALL/KITTELL
AVIATION...ASR
MARINE/BEACHES...HALL
SYNOPSIS...SUKUP
WWW.WEATHER.GOV/LOSANGELES
AREA FORECAST DISCUSSION
NWS PUEBLO CO
1148 PM MDT MON AUG 25 2014
.UPDATE...
ISSUED AT 1015 PM MDT MON AUG 25 2014
UPDATED TO EXPIRE THE TSTORM WATCH. ANY ACTIVITY TONIGHT SHOULD
STAY SUB SVR.
ALSO ISSUED A FLASH FLOOD WATCH FOR TOMORROW. MODEL CONSENSUS
AND CURRENT OBS INDICATE LOTS OF SUBTROPICAL MOISTURE HEADED
OUR WAY. DEWPOINTS WILL REMAIN IN THE 50S AND 60S. PREC H20 IN
THE 1-1.5 INCH RANGE. DEEP SRLY FLOW IN PLACE. LOOKS PRETTY
CONDUCIVE TO LOCALIZED FLASH FLOODING. STORMS SHOULD SPREAD FROM
THE SW MTS EARLY TO THE ERN MTS AND I-25 BY AFTERNOON...THEN ON TO
THE PLAINS BY LATE AFTERNOON OR EVE. ROSE
UPDATE ISSUED AT 753 PM MDT MON AUG 25 2014
UPDATED TO CLEAR PUEBLO CTY FROM THE WATCH...AND ADJUST POPS PER
RADAR AND MODEL TRENDS. ROSE
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 06Z TAFS THROUGH 06Z TUESDAY NIGHT)
ISSUED AT 1137 PM MDT MON AUG 25 2014
MAIN AVN CONCERN IS THE POTENTIAL FOR SIGNIFICANT IMPACTS
FOR THE TERMINALS ON TUESDAY...ESPECIALLY AFTER 20Z. A STORM
SYSTEM MOVING INTO EASTERN NV/W UT TUE AFTERNOON WILL REINFORCE
A STRONG MONSOONAL FLOW OF MOISTURE INTO SE CO. THIS WILL BRING
THE POTENTIAL FOR NUMEROUS SHOWERS AND STORMS...SOME OF WHICH
COULD BE ON THE STRONG SIDE WITH HEAVY RAIN AND HAIL. VIS COULD
BE REDUCED TO IFR OR LOWER AT TIMES IN THE STRONGER STORMS
TUE AFTERNOON AND EVENING. STORMS WILL MOVE EWD TO THE PLAINS BY
LATE TUE EVE...BUT WILL LEAVE LINGERING POCKETS OF MVFR TO
POTENTIALLY IFR CIGS THROUGH WED MORNING. THIS STORM SYSTEM
WILL LINGER THROUGH THURSDAY...AND WILL BRING THE THREAT OF MORE
HEAVY RAIN AND STORMS BOTH LATE WEDNESDAY AND AGAIN THURSDAY.
FZG LEVELS WILL LOWER TO ABOUT 6K FT AGL BY THU. ROSE
&&
.PUB WATCHES/WARNINGS/ADVISORIES...
FLASH FLOOD WATCH FROM TUESDAY AFTERNOON THROUGH LATE TUESDAY
NIGHT FOR COZ066>068-072>089-093>099.
&&
$$
UPDATE...ROSE
SHORT TERM...PETERSEN
LONG TERM...MOORE
AVIATION...ROSE
AREA FORECAST DISCUSSION
NWS PUEBLO CO
1020 PM MDT MON AUG 25 2014
.UPDATE...
ISSUED AT 1015 PM MDT MON AUG 25 2014
UPDATED TO EXPIRE THE TSTORM WATCH. ANY ACTIVITY TONIGHT SHOULD
STAY SUB SVR.
ALSO ISSUED A FLASH FLOOD WATCH FOR TOMORROW. MODEL CONSENSUS
AND CURRENT OBS INDICATE LOTS OF SUBTROPICAL MOISTURE HEADED
OUR WAY. DEWPOINTS WILL REMAIN IN THE 50S AND 60S. PREC H20 IN
THE 1-1.5 INCH RANGE. DEEP SRLY FLOW IN PLACE. LOOKS PRETTY
CONDUCIVE TO LOCALIZED FLASH FLOODING. STORMS SHOULD SPREAD FROM
THE SW MTS EARLY TO THE ERN MTS AND I-25 BY AFTERNOON...THEN ON TO
THE PLAINS BY LATE AFTERNOON OR EVE. ROSE
UPDATE ISSUED AT 753 PM MDT MON AUG 25 2014
UPDATED TO CLEAR PUEBLO CTY FROM THE WATCH...AND ADJUST POPS PER
RADAR AND MODEL TRENDS. ROSE
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...
FLASH FLOOD WATCH FROM TUESDAY AFTERNOON THROUGH LATE TUESDAY
NIGHT FOR COZ066>068-072>089-093>099.
&&
$$
UPDATE...ROSE
SHORT TERM...PETERSEN
LONG TERM...MOORE
AVIATION...PETERSEN
AREA FORECAST DISCUSSION...UPDATED
NWS TAMPA BAY RUSKIN FL
525 AM EDT TUE AUG 26 2014
...UPDATED AVIATION SECTION FOR LOWER STRATUS POTENTIAL EARLY THIS
MORNING AT KLAL AND KTPA...
.SYNOPSIS...
08Z WATER VAPOR AND H4 RAP ANALYSIS SHOWS A PATTERN THAT HAS NOT
BEEN ALL THAT COMMON THIS SUMMER. IT IS HARD TO BELIEVE...BUT THE
MID/UPPER LEVEL PATTERN CONSISTS OF LONGWAVE TROUGHING OVER THE
WESTERN CONUS...AND DOWNSTREAM AMPLIFIED RIDGING EXTENDING FROM THE
SOUTHERN PLAINS TO THE EASTERN SEABOARD. MUCH OF THIS SUMMER SEASON
HAS BEEN THE OPPOSITE WITH A STUBBORN TROUGH OVER THE EAST. THE
FLORIDA PENINSULA RESIDES MAINLY SOUTH OF THIS LARGE RIDGE IN A DEEP
LAYER NORTHEAST FLOW REGIME BETWEEN THIS FEATURE AND WHAT IS NOW
HURRICANE CRISTOBAL SPINNING TO THE EAST OF THE BAHAMAS. THIS
NORTHEAST FLOW IS DELIVERING A VERY ANOMALOUS MID-LEVEL AIRMASS
ABOVE OUR HEADS IN TERMS OF TEMPERATURES AND DRY AIR FOR THE NEXT
24-36 HOURS. THIS AIRMASS IS ALREADY ARRIVING PER WV IMAGERY AND THE
LATEST KTBW SOUNDING PROFILE...AND WILL ONLY FURTHER DRY OUT
OVERNIGHT INTO TUESDAY MORNING. THE KTBW EVENING SOUNDING SHOWED A
PW VALUES ALREADY DOWN TO 1.27"...WITH DECENT DEWPOINT DEPRESSIONS
ABOVE THE DIURNAL MIXED LAYER ALL THE WAY UP THROUGH THE TROP
COLUMN. THIS PW VALUE IS SLIGHTLY MORE THAN 2 STANDARD DEVIATIONS
BELOW CLIMATOLOGY FOR THE LAST WEEK OF AUGUST...AND EXPECT PW VALUES
DURING THE DAY ON TUESDAY TO DROP EVEN FURTHER. MINIMUM ALL TIME
VALUES FOR LATE AUGUST ARE AROUND 0.8". WE WILL NOT GET DOWN THAT
MUCH...BUT STILL AN INCREDIBLY DRY COLUMN FOR THIS TIME OF YEAR.
THE OTHER AND EVEN MORE IMPRESSIVE FEATURE OF THIS AIRMASS IS THE
MID-LEVEL TEMPS. FOR SIMPLICITY LETS FOCUS IN ON THE 500MB / H5
TEMPERATURES. THE KTBW SOUNDING MEASURED A TEMPERATURE OF -2C.
TEMPERATURES THIS WARM ARE ALMOST UNHEARD OF IN AUGUST...AND IT IS
FORECAST BY THE RELIABLE GUIDANCE TO WARM ANOTHER DEGREE OR 2 TODAY.
USING THE NAEFS (NORTH AMERICAN ENSEMBLE FORECAST SYSTEM) COMPARED
TO THE CFSR (CLIMATE FORECAST SYSTEM REANALYSIS 1979-2009)
CLIMATOLOGY FOR A 3 WEEK PERIOD CENTERED ON TODAY...WE FIND THAT THE
FORECAST H5 TEMPS ABOVE THE FL PENINSULA ARE ALL ABOVE THE 99TH
PERCENTILE OF VALUES...WITH MUCH OF THE AREA AT H5 EXPERIENCING
TEMPS HIGHER THAN ANYTHING SEEN IN THIS 30 YEAR CLIMATOLOGICAL
RECORD. SUCH ANOMALOUS VALUES ARE JUST INTERESTING FROM A CLIMATE
AND METEOROLOGICAL PERSPECTIVE. SO...GUESS WHAT? DO NOT SEE MUCH IN
THE WAY OF DEEP CONVECTION AROUND TODAY (IF ANY).
AT THE SURFACE...WE ARE EXPERIENCING A TIGHT GRADIENT AND ELEVATED
NORTHEAST FLOW BETWEEN 1020+MB HIGH PRESSURE TO OUR NORTH...AND
HURRICANE CRISTOBAL TO OUR EAST. EXPERIENCED A GUSTY DAY ON MONDAY
WITHIN THIS GRADIENT...HOWEVER THE REAL IMPACTS HAVE BEEN OVER THE
COASTAL WATERS OF THE EASTERN GULF...WHERE A RARE SUMMER ADVISORY
EVENT IS UNDERWAY EARLY THIS MORNING. THIS ADVISORY SHOULD BE
BRIEF IN DURATION WITH WINDS DROPPING SOMEWHAT DURING THE DAY ON
TUESDAY...AND THEN IMPROVING CONDITIONS THROUGH THE MIDDLE OF THE
WEEK.
&&
.SHORT TERM (TODAY THROUGH WEDNESDAY)...
TODAY...
JUST ABOUT AS QUIET A SUMMER DAY IN TERMS OF DEEP CONVECTION AS WE
SEE DURING THE SUMMER MONTHS. THE ATMOSPHERE ABOVE 850MB IS VERY
HOSTILE TOWARD CONVECTIVE COLUMNS THROUGHOUT THE FORECAST AREA AND
WILL REMAIN SO THROUGH THE DAY. MINIMUM THETAE VALUES BETWEEN 850MB
AND 500MB ARE BELOW 320K...AND IN SOME GUIDANCE MEMBERS DOWN BELOW
315K. THIS IS ABOUT AS LOW AS WE SEE THIS TIME OF YEAR AND THE DEPTH
OF THESE LOW VALUES SUGGESTS MAINLY A SHALLOW CU FIELD WITH LITTLE
IN THE WAY OF VERTICAL GROWTH BEFORE SIGNIFICANT ENTRAINMENT OF THIS
LOW THETAE AIR BEGINS. WITH THIS IN MIND...HAVE RAIN CHANCES DOWN AT
10% OR LESS TODAY FOR ALL AREAS. THERE IS SOME ATLANTIC MOISTURE IN
THE LOWEST LEVELS OF THE ATMOSPHERE TO SUPPORT THE SHALLOW CU
FIELD...BUT CAN NOT SEE ANYTHING MORE THAN A FEW ISOLATED AND
SHALLOW SPEED CONVERGENCE SPRINKLES MAKING THERE WAY INTO THE
FORECAST AREA WITHIN THE NE FLOW FROM THE ATLANTIC COAST. SOME OF
THE HIRES GUIDANCE MEMBERS TRY TO PRODUCE A FEW SHOWERS RIGHT AT THE
GULF COAST VERY LATE IN THE DAY AS THE LOCAL GRADIENT DIURNALLY
WEAKENS OVER THE NEARSHORE WATERS AND PROVIDES A BRIEF WINDOW OF
SURFACE FOCUS/CONVERGENCE FOR UPWARD MOTION. HOWEVER...THESE MODELS
ARE GENERALLY A BIT AGGRESSIVE...AND WILL HOLD WITH THE IDEA THAT
THE COLUMN IS SIMPLY TO HOSTILE FOR ANY OF THESE SHOWERS TO GET
ESTABLISHED.
SO...LOOK FOR A GENERALLY DRY DAY UNDER A FEW-SCT CU FIELD AND
TEMPERATURES CLIMBING INTO THE LOWER TO MIDDLE 90S. WINDS WILL
BECOME A LITTLE GUSTY WITHIN A FEW HOURS OF SUNRISE...BUT LIKELY
WILL NOT BE AS PRONOUNCED AS THEY WERE ON MONDAY.
TONIGHT...
NOT MUCH SENSIBLE WEATHER TO TALK ABOUT. THE DRY CONDITIONS WILL
CONTINUE OTHER THAN AN ISOLATED SPEED CONVERGENCE SPRINKLE MAKING IT
FAR ENOUGH INLAND FROM THE EAST COAST TO REACH EASTERN
POLK/HIGHLANDS COUNTIES. THE LOSS OF DIURNAL MIXING WILL END THE
GUSTY NATURE TO THE WINDS QUICKLY AFTER SUNSET OVER THE LANDMASS.
WINDS WILL ACTUALLY INCREASE AT THIS POINT OVER THE COASTAL WATERS
ONCE AGAIN...AND MORE CAN BE READ ABOUT THIS NEXT EASTERLY NOCTURNAL
SURGE IN THE MARINE DISCUSSION BELOW.
WEDNESDAY LOOKS TO BE ANOTHER GENERALLY QUIET DAY FOR MUCH OF THE
FORECAST AREA AS DRY AND WARM AIR REMAIN OVERHEAD. SOME UNCERTAINLY
IN THE THUNDERSTORM CHANCES DOWN TOWARD THE FORT MYERS FOR THE
SECOND HALF OF THE AFTERNOON AND EVENING AS THERE IS SOME
DISAGREEMENT IN THE GUIDANCE AS TO THE RATE OF MOISTURE RETURN AND
LOW LEVEL FOCUS RETURN FROM THE SOUTH. ALL THE RELIABLE GUIDANCE
MEMBERS HAVE A WEAK TROUGH EXTENDING ACROSS THE SOUTHEAST GULF AND
FLORIDA STRAITS ON WEDNESDAY. THIS TROUGH AXIS MARKS THE LEADING
EDGE OF THE DEEP LAYER MOISTURE AND NOSE OF AN EXPANDING LOW LEVEL
THETAE RIDGE. THE 00Z NAM IS THE MOST AGGRESSIVE WITH THE NORTHWARD
PROGRESSION OF THIS THETAE RIDGE AND BRINGS A DECENT SWATH OF
MOISTURE RETURN AND RESULTING VERTICAL MOTION BELOW 700MB INTO THE
SOUTHERN FL PENINSULA...INCLUDING LEE/CHARLOTTE COUNTIES LATE IN THE
DAY. THE GFS IS IN THE MIDDLE OF THE GUIDANCE ENVELOPE...WITH THE
00Z ECMWF THE SLOWEST AND LEAST AGGRESSIVE TO BRING THE MOISTURE
BACK TO OUR SOUTHERN ZONES. THE NAM UPGRADE FROM EARLIER THIS MONTH
IS STILL FAIRLY RECENT AND THERE HAS NOT BEEN ENOUGH TIME TO REALLY
FIGURE OUT ALL ITS BIASES ETC. NOT GOING TO SAY ITS SOLUTION IS NOT
CORRECT...BUT FOR THIS FORECAST CYCLE...A MORE CONSERVATIVE
PHILOSOPHY IN LINE WITH THE GFS SEEMS MORE APPROPRIATE. WILL BRING A
CHANCE FOR A FEW LATE DAY STORMS INTO THE FORT MYERS AREA...BUT KEEP
LIKELY WORDING OUT OF THE FORECAST (AS THE NAM WOULD SUGGEST).
FURTHER NORTH...TOWARD TAMPA BAY AND THE NATURE COAST...CONFIDENCE
IS HIGHER IN NO SIGNIFICANT MOISTURE RETURN DURING THE DAYLIGHT
HOURS. TOUGH THIS TIME OF YEAR AS A FORECASTER TO GO YET ANOTHER DAY
WITH NO STORM CHANCES...BUT WILL STILL KEEP RAIN CHANCES WELL BELOW
CLIMO...WITH JUST A 15-20% POP FOR MOST AREAS. NORTH OF BROOKSVILLE
IS THE ONLY PLACE CONFIDENCE IS HIGH ENOUGH TO LEAVE RAIN MENTION
OUT OF THE FORECAST. THURSDAY LOOKS TO BE THE TRUE TRANSITION DAY
FOR MOST AREAS...WITH DEEPER LAYER MOISTURE AND INCREASING STORMS
CHANCES EXPANDING NORTHWARD ACROSS THE PENINSULA.
&&
.LONG TERM (THURSDAY THROUGH NEXT MONDAY)...
A COMPACT UPPER RIDGE INITIALLY ACROSS SOUTH GA AND NORTH FL BUILDS
AND ELONGATES...EXTENDING FROM THE NORTHERN GULF TO THE ATLANTIC
WATERS OFF THE SOUTHEAST AND MID-ATLANTIC COASTS. THIS RIDGE
DOMINATES THE AREA ALTHOUGH A WEAK UPPER LOW/TROUGH APPROACHES THE
BAHAMAS BY THE END OF THE PERIOD. MEANWHILE AT THE SURFACE CRISTOBAL
EXITS AS HIGH PRESSURE BEGINS TO RIDGE IN ACROSS SOUTH FL. THIS
LIFTS INTO CENTRAL FL FRI AND CONTINUES NORTHWARD...RESIDING ACROSS
NORTHERN FL THROUGH THE HOLIDAY WEEKEND WITH A BROAD AND RELAXED
PRESSURE PATTERN.
THE UPPER RIDGE WILL HELP KEEP TEMPERATURES ON THE WARM SIDE OF
NORMAL...WITH THE HIGHS ABOVE NORMAL BY A COUPLE OF DEGREES. THE
SURFACE RIDGE SLIDING NORTH PROVIDES ENOUGH MOISTURE...MODEL PWAT
VALUES RUN IN THE 1.9 TO 2 INCH RANGE...FOR ISOLATED TO SCATTERED
SHOWERS AND THUNDERSTORMS. SOUTHEAST BECOMING SOUTHERLY LOW LEVEL
FLOW...BUT WITH ONSHORE FLOW IN THE AFTERNOONS...WILL RESULT IN THE
MOST COVERAGE INLAND IN THE AFTERNOON AND EVENING HOURS. ISOLATED
OVERNIGHT ACTIVITY ON THE GULF MAY DRIFT OVER SOME COASTAL LOCATIONS
IN THE MORNINGS.
&&
.AVIATION...
VFR CONDITIONS PREVAIL ACROSS MUCH THE FORECAST AREA EARLY THIS
MORNING. HAVE SEEN AN AREA OF LOWER STRATUS WITH CEILINGS IN THE IFR
RANGE DEVELOP ALONG AND NORTH OF THE I-4 CORRIDOR IN PAST COUPLE OF
HOURS. HAVE INCLUDED TEMPOS FOR BRIEF IFR CIGS AT KLAL AND KTPA
THROUGH EARLY THIS MORNING. ANY CIG RESTRICTIONS ALONG THE I-4
CORRIDOR SHOULD LIFT WITHIN A FEW HOURS OF SUNRISE. ELSEWHERE VFR
CONDITIONS WILL PREVAIL. CHANCES FOR THUNDERSTORMS TODAY ARE VERY
LOW FOR ALL THE TERMINALS. ONLY AVIATION CONCERNS WILL BE GUSTY
NORTHEAST WINDS FROM MID MORNING THROUGH THE AFTERNOON HOURS. WINDS
WILL BECOME LESS GUSTY AFTER SUNSET THIS EVENING.
&&
.MARINE...
A TIGHT GRADIENT BETWEEN HIGH PRESSURE TO OUR NORTH AND HURRICANE
CRISTOBAL TO THE EAST OF FLORIDA ARE RESULTING IN AN UNSEASONABLY
STRONG EAST TO NORTHEAST FLOW ACROSS THE EASTERN GULF OF MEXICO.
ADVISORY LEVEL WINDS WILL CONTINUE EARLY THIS MORNING OVER THE
COASTAL WATERS AND THEN SLOWLY SUBSIDE BELOW HEADLINE CRITERIA
THROUGH THE MORNING HOURS. ANOTHER PERIOD OF CAUTIONARY LEVEL WINDS
IS EXPECTED TONIGHT INTO EARLY WEDNESDAY MORNING BEFORE ONCE AGAIN
SUBSIDING DURING THE THE DAYLIGHT HOURS. WINDS AND SEAS SHOULD THEN
REMAIN BELOW HEADLINE CRITERIA FOR THE REMAINDER OF THE FORECAST
PERIOD.
&&
.FIRE WEATHER...
DESPITE DRIER CONDITIONS AND LITTLE TO NO RAIN CHANCES TODAY...
RELATIVE HUMIDITY VALUES WILL REMAIN ABOVE CRITICAL LEVELS. WINDS
HOWEVER WILL BE GUSTY OUT OF THE NORTHEAST AND EAST. MOISTURE AND
CHANCES FOR AFTERNOON STORMS WILL BEGIN TO INCREASE ONCE AGAIN
DURING THE MIDDLE PORTION OF THE WEEK AND BE BACK TO NORMAL LATE
AUGUST CONDITIONS BY THE END OF THE WEEK.
&&
.PRELIMINARY POINT TEMPS/POPS...
TPA 94 75 94 78 / 10 10 20 10
FMY 95 74 94 78 / 10 10 40 20
GIF 93 72 94 74 / 10 10 20 10
SRQ 94 74 94 77 / 10 10 20 10
BKV 94 70 94 71 / 10 10 20 10
SPG 94 79 93 80 / 10 10 20 10
&&
.TBW WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
GULF WATERS...SMALL CRAFT ADVISORY UNTIL 10 AM EDT THIS MORNING FOR
BONITA BEACH TO ENGLEWOOD OUT 20 TO 60 NM-ENGLEWOOD
TO TARPON SPRINGS OUT 20 TO 60 NM-TARPON SPRINGS TO
SUWANNEE RIVER OUT 20 TO 60 NM.
SMALL CRAFT ADVISORY UNTIL 8 AM EDT THIS MORNING FOR
BONITA BEACH TO ENGLEWOOD OUT 20 NM-ENGLEWOOD TO
TARPON SPRINGS OUT 20 NM-TARPON SPRINGS TO SUWANNEE
RIVER OUT 20 NM.
&&
$$
SYNOPSIS/SHORT TERM/AVIATION/MARINE/FIRE WX...MROCZKA
LONG TERM...RUDE
AREA FORECAST DISCUSSION...RESENT
NWS TAMPA BAY RUSKIN FL
422 AM EDT TUE AUG 26 2014
.SYNOPSIS...
08Z WATER VAPOR AND H4 RAP ANALYSIS SHOWS A PATTERN THAT HAS NOT
BEEN ALL THAT COMMON THIS SUMMER. IT IS HARD TO BELIEVE...BUT THE
MID/UPPER LEVEL PATTERN CONSISTS OF LONGWAVE TROUGHING OVER THE
WESTERN CONUS...AND DOWNSTREAM AMPLIFIED RIDGING EXTENDING FROM THE
SOUTHERN PLAINS TO THE EASTERN SEABOARD. MUCH OF THIS SUMMER SEASON
HAS BEEN THE OPPOSITE WITH A STUBBORN TROUGH OVER THE EAST. THE
FLORIDA PENINSULA RESIDES MAINLY SOUTH OF THIS LARGE RIDGE IN A DEEP
LAYER NORTHEAST FLOW REGIME BETWEEN THIS FEATURE AND WHAT IS NOW
HURRICANE CRISTOBAL SPINNING TO THE EAST OF THE BAHAMAS. THIS
NORTHEAST FLOW IS DELIVERING A VERY ANOMALOUS MID-LEVEL AIRMASS
ABOVE OUR HEADS IN TERMS OF TEMPERATURES AND DRY AIR FOR THE NEXT
24-36 HOURS. THIS AIRMASS IS ALREADY ARRIVING PER WV IMAGERY AND THE
LATEST KTBW SOUNDING PROFILE...AND WILL ONLY FURTHER DRY OUT
OVERNIGHT INTO TUESDAY MORNING. THE KTBW EVENING SOUNDING SHOWED A
PW VALUES ALREADY DOWN TO 1.27"...WITH DECENT DEWPOINT DEPRESSIONS
ABOVE THE DIURNAL MIXED LAYER ALL THE WAY UP THROUGH THE TROP
COLUMN. THIS PW VALUE IS SLIGHTLY MORE THAN 2 STANDARD DEVIATIONS
BELOW CLIMATOLOGY FOR THE LAST WEEK OF AUGUST...AND EXPECT PW VALUES
DURING THE DAY ON TUESDAY TO DROP EVEN FURTHER. MINIMUM ALL TIME
VALUES FOR LATE AUGUST ARE AROUND 0.8". WE WILL NOT GET DOWN THAT
MUCH...BUT STILL AN INCREDIBLY DRY COLUMN FOR THIS TIME OF YEAR.
THE OTHER AND EVEN MORE IMPRESSIVE FEATURE OF THIS AIRMASS IS THE
MID-LEVEL TEMPS. FOR SIMPLICITY LETS FOCUS IN ON THE 500MB / H5
TEMPERATURES. THE KTBW SOUNDING MEASURED A TEMPERATURE OF -2C.
TEMPERATURES THIS WARM ARE ALMOST UNHEARD OF IN AUGUST...AND IT IS
FORECAST BY THE RELIABLE GUIDANCE TO WARM ANOTHER DEGREE OR 2 TODAY.
USING THE NAEFS (NORTH AMERICAN ENSEMBLE FORECAST SYSTEM) COMPARED
TO THE CFSR (CLIMATE FORECAST SYSTEM REANALYSIS 1979-2009)
CLIMATOLOGY FOR A 3 WEEK PERIOD CENTERED ON TODAY...WE FIND THAT THE
FORECAST H5 TEMPS ABOVE THE FL PENINSULA ARE ALL ABOVE THE 99TH
PERCENTILE OF VALUES...WITH MUCH OF THE AREA AT H5 EXPERIENCING
TEMPS HIGHER THAN ANYTHING SEEN IN THIS 30 YEAR CLIMATOLOGICAL
RECORD. SUCH ANOMALOUS VALUES ARE JUST INTERESTING FROM A CLIMATE
AND METEOROLOGICAL PERSPECTIVE. SO...GUESS WHAT? DO NOT SEE MUCH IN
THE WAY OF DEEP CONVECTION AROUND TODAY (IF ANY).
AT THE SURFACE...WE ARE EXPERIENCING A TIGHT GRADIENT AND ELEVATED
NORTHEAST FLOW BETWEEN 1020+MB HIGH PRESSURE TO OUR NORTH...AND
HURRICANE CRISTOBAL TO OUR EAST. EXPERIENCED A GUSTY DAY ON MONDAY
WITHIN THIS GRADIENT...HOWEVER THE REAL IMPACTS HAVE BEEN OVER THE
COASTAL WATERS OF THE EASTERN GULF...WHERE A RARE SUMMER ADVISORY
EVENT IS UNDERWAY EARLY THIS MORNING. THIS ADVISORY SHOULD BE
BRIEF IN DURATION WITH WINDS DROPPING SOMEWHAT DURING THE DAY ON
TUESDAY...AND THEN IMPROVING CONDITIONS THROUGH THE MIDDLE OF THE
WEEK.
&&
.SHORT TERM (TODAY THROUGH WEDNESDAY)...
TODAY...
JUST ABOUT AS QUIET A SUMMER DAY IN TERMS OF DEEP CONVECTION AS WE
SEE DURING THE SUMMER MONTHS. THE ATMOSPHERE ABOVE 850MB IS VERY
HOSTILE TOWARD CONVECTIVE COLUMNS THROUGHOUT THE FORECAST AREA AND
WILL REMAIN SO THROUGH THE DAY. MINIMUM THETAE VALUES BETWEEN 850MB
AND 500MB ARE BELOW 320K...AND IN SOME GUIDANCE MEMBERS DOWN BELOW
315K. THIS IS ABOUT AS LOW AS WE SEE THIS TIME OF YEAR AND THE DEPTH
OF THESE LOW VALUES SUGGESTS MAINLY A SHALLOW CU FIELD WITH LITTLE
IN THE WAY OF VERTICAL GROWTH BEFORE SIGNIFICANT ENTRAINMENT OF THIS
LOW THETAE AIR BEGINS. WITH THIS IN MIND...HAVE RAIN CHANCES DOWN AT
10% OR LESS TODAY FOR ALL AREAS. THERE IS SOME ATLANTIC MOISTURE IN
THE LOWEST LEVELS OF THE ATMOSPHERE TO SUPPORT THE SHALLOW CU
FIELD...BUT CAN NOT SEE ANYTHING MORE THAN A FEW ISOLATED AND
SHALLOW SPEED CONVERGENCE SPRINKLES MAKING THERE WAY INTO THE
FORECAST AREA WITHIN THE NE FLOW FROM THE ATLANTIC COAST. SOME OF
THE HIRES GUIDANCE MEMBERS TRY TO PRODUCE A FEW SHOWERS RIGHT AT THE
GULF COAST VERY LATE IN THE DAY AS THE LOCAL GRADIENT DIURNALLY
WEAKENS OVER THE NEARSHORE WATERS AND PROVIDES A BRIEF WINDOW OF
SURFACE FOCUS/CONVERGENCE FOR UPWARD MOTION. HOWEVER...THESE MODELS
ARE GENERALLY A BIT AGGRESSIVE...AND WILL HOLD WITH THE IDEA THAT
THE COLUMN IS SIMPLY TO HOSTILE FOR ANY OF THESE SHOWERS TO GET
ESTABLISHED.
SO...LOOK FOR A GENERALLY DRY DAY UNDER A FEW-SCT CU FIELD AND
TEMPERATURES CLIMBING INTO THE LOWER TO MIDDLE 90S. WINDS WILL
BECOME A LITTLE GUSTY WITHIN A FEW HOURS OF SUNRISE...BUT LIKELY
WILL NOT BE AS PRONOUNCED AS THEY WERE ON MONDAY.
TONIGHT...
NOT MUCH SENSIBLE WEATHER TO TALK ABOUT. THE DRY CONDITIONS WILL
CONTINUE OTHER THAN AN ISOLATED SPEED CONVERGENCE SPRINKLE MAKING IT
FAR ENOUGH INLAND FROM THE EAST COAST TO REACH EASTERN
POLK/HIGHLANDS COUNTIES. THE LOSS OF DIURNAL MIXING WILL END THE
GUSTY NATURE TO THE WINDS QUICKLY AFTER SUNSET OVER THE LANDMASS.
WINDS WILL ACTUALLY INCREASE AT THIS POINT OVER THE COASTAL WATERS
ONCE AGAIN...AND MORE CAN BE READ ABOUT THIS NEXT EASTERLY NOCTURNAL
SURGE IN THE MARINE DISCUSSION BELOW.
WEDNESDAY LOOKS TO BE ANOTHER GENERALLY QUIET DAY FOR MUCH OF THE
FORECAST AREA AS DRY AND WARM AIR REMAIN OVERHEAD. SOME UNCERTAINLY
IN THE THUNDERSTORM CHANCES DOWN TOWARD THE FORT MYERS FOR THE
SECOND HALF OF THE AFTERNOON AND EVENING AS THERE IS SOME
DISAGREEMENT IN THE GUIDANCE AS TO THE RATE OF MOISTURE RETURN AND
LOW LEVEL FOCUS RETURN FROM THE SOUTH. ALL THE RELIABLE GUIDANCE
MEMBERS HAVE A WEAK TROUGH EXTENDING ACROSS THE SOUTHEAST GULF AND
FLORIDA STRAITS ON WEDNESDAY. THIS TROUGH AXIS MARKS THE LEADING
EDGE OF THE DEEP LAYER MOISTURE AND NOSE OF AN EXPANDING LOW LEVEL
THETAE RIDGE. THE 00Z NAM IS THE MOST AGGRESSIVE WITH THE NORTHWARD
PROGRESSION OF THIS THETAE RIDGE AND BRINGS A DECENT SWATH OF
MOISTURE RETURN AND RESULTING VERTICAL MOTION BELOW 700MB INTO THE
SOUTHERN FL PENINSULA...INCLUDING LEE/CHARLOTTE COUNTIES LATE IN THE
DAY. THE GFS IS IN THE MIDDLE OF THE GUIDANCE ENVELOPE...WITH THE
00Z ECMWF THE SLOWEST AND LEAST AGGRESSIVE TO BRING THE MOISTURE
BACK TO OUR SOUTHERN ZONES. THE NAM UPGRADE FROM EARLIER THIS MONTH
IS STILL FAIRLY RECENT AND THERE HAS NOT BEEN ENOUGH TIME TO REALLY
FIGURE OUT ALL ITS BIASES ETC. NOT GOING TO SAY ITS SOLUTION IS NOT
CORRECT...BUT FOR THIS FORECAST CYCLE...A MORE CONSERVATIVE
PHILOSOPHY IN LINE WITH THE GFS SEEMS MORE APPROPRIATE. WILL BRING A
CHANCE FOR A FEW LATE DAY STORMS INTO THE FORT MYERS AREA...BUT KEEP
LIKELY WORDING OUT OF THE FORECAST (AS THE NAM WOULD SUGGEST).
FURTHER NORTH...TOWARD TAMPA BAY AND THE NATURE COAST...CONFIDENCE
IS HIGHER IN NO SIGNIFICANT MOISTURE RETURN DURING THE DAYLIGHT
HOURS. TOUGH THIS TIME OF YEAR AS A FORECASTER TO GO YET ANOTHER DAY
WITH NO STORM CHANCES...BUT WILL STILL KEEP RAIN CHANCES WELL BELOW
CLIMO...WITH JUST A 15-20% POP FOR MOST AREAS. NORTH OF BROOKSVILLE
IS THE ONLY PLACE CONFIDENCE IS HIGH ENOUGH TO LEAVE RAIN MENTION
OUT OF THE FORECAST. THURSDAY LOOKS TO BE THE TRUE TRANSITION DAY
FOR MOST AREAS...WITH DEEPER LAYER MOISTURE AND INCREASING STORMS
CHANCES EXPANDING NORTHWARD ACROSS THE PENINSULA.
&&
.LONG TERM (THURSDAY THROUGH NEXT MONDAY)...
A COMPACT UPPER RIDGE INITIALLY ACROSS SOUTH GA AND NORTH FL BUILDS
AND ELONGATES...EXTENDING FROM THE NORTHERN GULF TO THE ATLANTIC
WATERS OFF THE SOUTHEAST AND MID-ATLANTIC COASTS. THIS RIDGE
DOMINATES THE AREA ALTHOUGH A WEAK UPPER LOW/TROUGH APPROACHES THE
BAHAMAS BY THE END OF THE PERIOD. MEANWHILE AT THE SURFACE CRISTOBAL
EXITS AS HIGH PRESSURE BEGINS TO RIDGE IN ACROSS SOUTH FL. THIS
LIFTS INTO CENTRAL FL FRI AND CONTINUES NORTHWARD...RESIDING ACROSS
NORTHERN FL THROUGH THE HOLIDAY WEEKEND WITH A BROAD AND RELAXED
PRESSURE PATTERN.
THE UPPER RIDGE WILL HELP KEEP TEMPERATURES ON THE WARM SIDE OF
NORMAL...WITH THE HIGHS ABOVE NORMAL BY A COUPLE OF DEGREES. THE
SURFACE RIDGE SLIDING NORTH PROVIDES ENOUGH MOISTURE...MODEL PWAT
VALUES RUN IN THE 1.9 TO 2 INCH RANGE...FOR ISOLATED TO SCATTERED
SHOWERS AND THUNDERSTORMS. SOUTHEAST BECOMING SOUTHERLY LOW LEVEL
FLOW...BUT WITH ONSHORE FLOW IN THE AFTERNOONS...WILL RESULT IN THE
MOST COVERAGE INLAND IN THE AFTERNOON AND EVENING HOURS. ISOLATED
OVERNIGHT ACTIVITY ON THE GULF MAY DRIFT OVER SOME COASTAL LOCATIONS
IN THE MORNINGS.
&&
.AVIATION...
VFR CONDITIONS PREVAIL ACROSS THE FORECAST AREA EARLY THIS MORNING
AND WILL CONTINUE FOR THE DURATION OF THE TAF PERIOD. CHANCES FOR
THUNDERSTORMS TODAY ARE VERY LOW FOR ALL THE TERMINALS. ONLY
AVIATION CONCERNS WILL BE GUSTY NORTHEAST WINDS FROM MID MORNING
THROUGH THE AFTERNOON HOURS. WINDS WILL BECOME LESS GUSTY AFTER
SUNSET THIS EVENING.
&&
.MARINE...
A TIGHT GRADIENT BETWEEN HIGH PRESSURE TO OUR NORTH AND HURRICANE
CRISTOBAL TO THE EAST OF FLORIDA ARE RESULTING IN AN UNSEASONABLY
STRONG EAST TO NORTHEAST FLOW ACROSS THE EASTERN GULF OF MEXICO.
ADVISORY LEVEL WINDS WILL CONTINUE EARLY THIS MORNING OVER THE
COASTAL WATERS AND THEN SLOWLY SUBSIDE BELOW HEADLINE CRITERIA
THROUGH THE MORNING HOURS. ANOTHER PERIOD OF CAUTIONARY LEVEL WINDS
IS EXPECTED TONIGHT INTO EARLY WEDNESDAY MORNING BEFORE ONCE AGAIN
SUBSIDING DURING THE THE DAYLIGHT HOURS. WINDS AND SEAS SHOULD THEN
REMAIN BELOW HEADLINE CRITERIA FOR THE REMAINDER OF THE FORECAST
PERIOD.
&&
.FIRE WEATHER...
DESPITE DRIER CONDITIONS AND LITTLE TO NO RAIN CHANCES TODAY...
RELATIVE HUMIDITY VALUES WILL REMAIN ABOVE CRITICAL LEVELS. WINDS
HOWEVER WILL BE GUSTY OUT OF THE NORTHEAST AND EAST. MOISTURE AND
CHANCES FOR AFTERNOON STORMS WILL BEGIN TO INCREASE ONCE AGAIN
DURING THE MIDDLE PORTION OF THE WEEK AND BE BACK TO NORMAL LATE
AUGUST CONDITIONS BY THE END OF THE WEEK.
&&
.PRELIMINARY POINT TEMPS/POPS...
TPA 94 75 94 78 / 10 10 20 10
FMY 95 74 94 78 / 10 10 40 20
GIF 93 72 94 74 / 10 10 20 10
SRQ 94 74 94 77 / 10 10 20 10
BKV 94 70 94 71 / 10 10 20 10
SPG 94 79 93 80 / 10 10 20 10
&&
.TBW WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
GULF WATERS...SMALL CRAFT ADVISORY UNTIL 10 AM EDT THIS MORNING FOR
BONITA BEACH TO ENGLEWOOD OUT 20 TO 60 NM-ENGLEWOOD
TO TARPON SPRINGS OUT 20 TO 60 NM-TARPON SPRINGS TO
SUWANNEE RIVER OUT 20 TO 60 NM.
SMALL CRAFT ADVISORY UNTIL 8 AM EDT THIS MORNING FOR
BONITA BEACH TO ENGLEWOOD OUT 20 NM-ENGLEWOOD TO
TARPON SPRINGS OUT 20 NM-TARPON SPRINGS TO SUWANNEE
RIVER OUT 20 NM.
&&
$$
SYNOPSIS/SHORT TERM/AVIATION/MARINE/FIRE WX...MROCZKA
LONG TERM...RUDE
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
1223 AM CDT TUE AUG 26 2014
.DISCUSSION...
710 PM CDT
THE FORECAST UPDATED TO REFLECT CURRENT STORM TRENDS AS WELL AS
TO ADD AREAS OF FOG TONIGHT. DO ENVISION CANCELLING THE SEVERE
THUNDERSTORM WATCH FOR THE REMAINDER OF THE CWA BY 8 PM.
AN AREA OF LOOSELY ORGANIZED STORMS CONTINUES TO PROPAGATE SLOWLY
SOUTHEAST WITH OCCASIONAL FINGERS OF SLIGHTLY BETTER WIND
SIGNATURES ON RADAR. VERY EFFICIENT RAINFALL WILL REMAIN THE
PRIMARY HAZARD WITH THESE AS THEY CROSS THROUGH SOUTHERN IROQUOIS
AND BENTON COUNTIES. 00Z RAOB AND VAD WIND PROFILE FROM ILX
INDICATE SOUTHWEST FLOW AT 15-20 KT BETWEEN 3000-6000 FT...ENOUGH
TO HOLD UP THE OUTFLOW BOUNDARY NEAR THE I-74 CORRIDOR FROM NEAR
PEORIA TO BLOOMINGTON NORMAL BASED ON RADAR TRENDS. THIS FLOW DOES
NOT LOOK STRONG ENOUGH TO DEVELOP MUCH CONVECTION NORTH OF
THAT...SO OVERALL EXPECTING A QUIET EVENING FOR MUCH OF THE
FORECAST AREA.
WATER VAPOR AND LATE DAY VISIBLE SATELLITE INDICATE A SHEARED
SHORT WAVE MOVING EAST-NORTHEAST NEAR DES MOINES. WITH MINIMAL
CONVERGENCE IN THE 800-900MB LAYER /BASICALLY AT THE BASE OF THE
ELEVATED INSTABILITY/...IT IS DIFFICULT TO SAY WHAT THIS FEATURE
WILL DO IN TERMS OF SHOWERS OR CONVECTION LATE TONIGHT. HIGH
RESOLUTION GUIDANCE DOES VARY GREATLY...HOWEVER USING A SHORT
RANGE ENSEMBLE APPROACH INDICATES OVERLAP ACROSS NORTHWEST INTO
NORTH CENTRAL IL LATE. FOR NOW DO CONTINUE THE CHANCE OF THUNDER
OVERNIGHT...WITH SOMEWHAT HIGHER POPS IN THAT AREA.
BECAUSE OF THE RAIN-COOLED MOIST AIR GOING INTO DARK...AREAS OF
FOG SEEM MORE PROBABLE BY AFTER MIDNIGHT...SOME OF WHICH MAY BE
DENSE GIVEN SUCH LOW T/TD SPREADS AT PRESENT.
MTF
//PREV DISCUSSION...
325 PM CDT
SHORT TERM...THROUGH EARLY TUESDAY MORNING...
FOR THE REMAINDER OF THE AFTERNOON...MAIN FOCUS WILL CONTINUE TO BE
TWO 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 MAY CONTINUE INTO EARLY THIS EVENING AS WELL...WITH
SOME POTENTIAL FOR A FORWARD-PROPAGATING MCS ACROSS MAINLY THE
SOUTHERN HALF OF THE FORECAST AREA. THIS WOULD BE MAINLY CAPABLE
OF WIND. AS THE THUNDERSTORM ACTIVITY DIMINISHES LATER 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...TUESDAY THROUGH MONDAY...
TUESDAY AND WEDNESDAY...
THE MAIN CHANGE TO THE FORECAST DURING THIS PERIOD WAS TO SHIFT
THE HIGHER CHANCES FOR STORMS SOUTH AS THE FRONTAL BOUNDARY
ITSELF LOOKS TO BE FURTHER SOUTH THAN EARLIER FORECAST...LIKELY
HELPED BY EPISODES OF CONVECTION SUCH AS THIS AFTERNOON. BECAUSE
OF THIS...CHANCES OF STORMS IN THIS PERIOD LOOK TO BE GREATER IN
THE SOUTHERN FORECAST AREA THAN THE NORTH. LAKE ADJACENT AREAS
ALSO LOOK TO BE INFLUENCED BY LAKE AIR ON TUESDAY...POSSIBLY EVEN
BY MORNING. BECAUSE OF THAT HAVE ADJUSTED TEMPERATURES DOWNWARD ON
TUESDAY...WITH THE POSSIBILITY OF 90 NOW BEING HARBORED ONLY TO THE
FAR SOUTH...ALTHOUGH LIKE TODAY IF CONVECTION OCCURS THAT CAN
GREATLY DISRUPT THINGS. LOWER 80S LOOK MORE LIKELY NORTH WITH
UPPER 70S NEAR THE LAKE SHORE.
THERE COULD BE ONGOING ELEVATED STORM ACTIVITY FROM IA INTO
NORTHWESTERN/WESTERN IL AT DAYBREAK TUESDAY MOVING EASTWARD...THOUGH
THE DEGREE OF COVERAGE IS UNCERTAIN. MUCH LIKE TODAY...IF THERE IS
ENOUGH ACTIVITY IT COULD JUST CONTINUE TO FESTER EAST-SOUTHEAST INTO
THE ILLINOIS FORECAST AREA AND THEN FEED ON THE INSTABILITY IN THE
FAR SOUTHEAST PART OF THE AREA. EVEN IF THAT WERE NOT TO PAN
OUT...SCATTERED DEVELOPMENT OF STORMS LOOKS FAVORED IN THE AFTERNOON
ALONG THE BOUNDARY WHICH SHOULD BE DRAPED FROM WEST-TO-EAST NEAR
INTERSTATE 80. ANY THUNDERSTORM ACTIVITY WILL BE SIMILAR TO MUCH IN
THE PAST WEEK...POSSESSING HEAVY RAIN POTENTIAL AND ISOLATED GUSTY
WIND CONCERNS.
CHANCES FOR STORMS CONTINUE WEDNESDAY...MAINLY SOUTH...BEFORE 850MB
FLOW TURNS BRIEFLY MORE NORTHWESTERLY WEDNESDAY NIGHT.
THURSDAY INTO THE WEEKEND...
THE BOUNDARY REMAINS FORECAST TO RETURN NORTHWARD AS A WARM
FRONT...POSSIBLY ON THURSDAY...IN RESPONSE TO AN UPPER LOW MOVING
EAST FROM THE CENTRAL ROCKIES. A SURFACE LOW AHEAD OF THIS IS
FORECAST TO LIFT NORTHEAST...BUT OVERALL THIS LOOKS TO BE SLOW GIVEN
THE UPPER LEVEL FEATURE IS CUTOFF. TAPPING BACK INTO THE MOIST AIR
MASS THAT WE ARE PRESENTLY IN...IT WOULD APPEAR SHOWER AND STORM
CHANCES WOULD SPREAD BACK NORTHWARD ACROSS THE AREA AND LAST THROUGH
MUCH OF THIS TIME...ALTHOUGH MOST FAVORED AS WE GET INTO THE
STRONGER LOW LEVEL JET/MOISTURE TRANSPORT...WHICH IS DIFFICULT TO
TIME AT THIS POINT. THE TEMPERATURE FORECAST IS LOW
CONFIDENCE...WITH HIGHS SYNOPTICALLY FAVORED IN THE 80S...ALTHOUGH
CONVECTIVE AND/OR LAKE COOLING POSSIBLE EVERY DAY.
MTF
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 06Z...
* SHRA/TSRA PREDAWN THRU MID MORNING.
* POSSIBLE MVFR CIGS THIS MORNING.
* WIND SHIFT TO NORTH MID MORNING...THEN NORTHEAST TO 10KT EARLY
AFTERNOON. CMS
//DISCUSSION...UPDATED 06Z...
ISOLATED CONVECTION FIRING OVER NORTH CENTRAL IOWA IS EXPECTED TO
CONTINUE AND SPREAD EAST THROUGH THE OVERNIGHT HOURS. ADDITIONAL
CONVECTION COULD DEVELOP RIGHT OVER THE TERMINALS IN THE 09Z-11Z
TIME FRAME. THUS NO CHANGES TO CURRENT SHRA/VCTS MENTION OR TIMING
THOUGH TWEAKS MAY BE NEEDED AS TRENDS EMERGE INCLUDING THE
POTENTIAL FOR MORE THUNDER MENTION. THIS ACTIVITY IS THEN EXPECTED
TO MOVE SOUTHEAST OF THE AREA BY MID/LATE MORNING WITH ISOLATED
ACTIVITY POSSIBLE THIS AFTERNOON. ADDITIONAL SHRA/TSRA WILL BE
POSSIBLE LATE TUESDAY NIGHT INTO WEDNESDAY MORNING BUT IF IT WERE
TO OCCUR...PROBABLY SIMILAR TIMING TO THIS MORNING 09Z OR LATER
AND WILL TAKE A CLOSER LOOK FOR POSSIBLE MENTION WITH THE 12Z TAFS
LATER THIS MORNING.
MVFR CIGS/VIS OR BRIEF IFR WILL BE POSSIBLE WITH ANY SHRA/TSRA.
OTHERWISE...A LOW VFR DECK 3-5KFT CONTINUES TO EXPAND ACROSS THE
AREA. THIS MAY LOWER INTO MVFR BY MORNING BUT CONFIDENCE TO
INCLUDE ANY PREVAILING MVFR CIGS IS LOW.
A COLD FRONT WILL CONTINUE TO MOVE SOUTH ACROSS THE AREA THIS
MORNING. LIGHT SOUTHERLY WINDS WILL TURN WESTERLY BY DAYBREAK AND
THEN SHIFT TO THE NORTH AS THE FRONT PUSHES THROUGH. WIND
DIRECTION AFTER FROPA IS A BIT UNCERTAIN AND MAY SHIFT BACK TO
THE NORTHWEST BEFORE A LAKE BREEZE MOVES ACROSS NORTHEAST IL
SHIFTING WINDS TO THE NORTHEAST. SPEEDS OUTSIDE OF ANY
CONVECTIVE/OUTFLOW ACTIVITY SHOULD REMAIN UNDER 10KTS. HOWEVER
SPEEDS WITH THE FRONT COULD BE IN THE 10-15KT RANGE WITH
PREVAILING 10KTS POSSIBLE WITH AND BEHIND THE LAKE BREEZE. CMS
//ORD AND MDW CONFIDENCE...UPDATED 06Z...
* MEDIUM FOR SHRA/TSRA THIS MORNING.
* MEDIUM FOR WINDS THRU THE PERIOD.
* LOW FOR MVFR CIGS THIS MORNING. CMS
//OUTLOOK FOR ORD/MDW FOR 12Z WEDNESDAY-12Z MONDAY...UPDATED 00Z...
WEDNESDAY...SLIGHT CHANCE OF TSRA.
THURSDAY...CHANCE OF TSRA.
FRIDAY...CHANCE OF TSRA.
SATURDAY...CHANCE OF TSRA.
SUNDAY...CHANCE OF TSRA.
RODRIGUEZ
&&
.MARINE...
315 PM CDT
SCATTERED STORMS THIS AFTERNOON HAVE DISRUPTED THE WINDS SOME
ACROSS THE FAR SOUTHERN PART OF LAKE MICHIGAN.
OTHERWISE...SOUTHERLY FLOW IS ANTICIPATED MUCH OF TONIGHT ACROSS
THE LAKE. DEW POINTS ARE NOT AS HIGH AS THEY HAVE BEEN BUT STILL
NEAR OR AT THE WATER TEMPERATURE...THUS POTENTIALLY LEADING TO
SOME PATCHY FOG. A COLD FRONT WILL MOVE ACROSS THE LAKE LATE
TONIGHT INTO TUESDAY MORNING...TURNING WINDS NORTHERLY. EVENTUALLY
THIS BOUNDARY WILL SHIFT BACK NORTH ACROSS THE LAKE MOST LIKELY ON
THURSDAY OR THURSDAY NIGHT. SOUTHERLY WINDS WILL THEN BE SEEN OVER
THE LAKE BEFORE LOW PRESSURE PASSES NEAR THE NORTHERN PART OF THE
LAKE SOMETIME EARLY THIS WEEKEND.
MTF
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...NONE.
&&
$$
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FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
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WWW.TWITTER.COM/NWSCHICAGO
WWW.YOUTUBE.COM/NWSCHICAGO
Area Forecast Discussion
NATIONAL WEATHER SERVICE LINCOLN IL
1105 PM CDT Mon Aug 25 2014
.UPDATE...
ISSUED AT 822 PM CDT MON AUG 25 2014
Storms continue to slowly diminish early this evening and expect
that trend to continue over the next few hours as we lose daytime
heating and the storms track further south into the upper ridge.
Hi-res short term models providing mixed signals as to when
additional thunderstorms develop/move into our area late tonight
as a cold front edges slowly into western Illinois by morning.
Not very confident on any one solution at this point but it appears
the low level jet and 850 mb moisture convergence will be more
supportive of storms developing over Iowa late tonight and then
track into our west during the early morning hours. Series of
shortwaves expected to slowly break down the upper level ridge
and drag a frontal boundary south across our area early this
week, before the front heads back into our area late in the week
and into next week providing daily chances for showers and storms.
One more day of high heat and humidity levels on Tuesday before we
see a gradual downward trend in temps for the remainder of the week.
Zones have already been updated to reflect the cancellation of the
watch and timing trends with the showers and storms over east
central Illinois.
&&
.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 06Z TAFS through 06Z Tuesday night)
ISSUED AT 1100 PM CDT MON AUG 25 2014
Little change from previous discussion with the main concern
overnight being from lower vsbys due to fog and the threat
for more showers and storms, especially across the west and
northwest. Outflow boundary from this afternoon`s storms has
shifted well south of the forecast area this evening with an
east to southeast component to the surface winds thanks to a
meso-high that developed along the rear of the thundertorm
complex. What affect this outflow boundary will have on our
fog chances is not clear as a few nights ago we saw the same
thing happen during the late afternoon/early evening hours
with very little in the way of fog due to somewhat lower dew
points brought in with the outflow boundary. However, with
the rain we received with the storms, the low levels of the
atmosphere are saturated so any decrease in wind speeds overnight
should lead to at least patchy fog, which should lift across the
area by 13z.
A cool front will then push across the area during the day Tuesday
bringing a switch in winds and the threat for additional showers
and storms, which may push into our west as early as the 12z-15z
time frame. Outside any lower vsbys in fog early in the morning, it
still appears we should see mainly VFR conditions during the day.
Surface winds will be turning more into the southeast and then south
overnight with speeds of less than 10kts. Winds should then become
light northerly during the morning across the west and over the
east in the afternoon with speeds of 5 to 10 kts.
&&
.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 ILZ043>046-055-057.
&&
$$
UPDATE...SMITH
SHORT TERM...BARNES
LONG TERM...AUTEN
AVIATION...SMITH
AREA FORECAST DISCUSSION
NWS TOPEKA KS
401 AM CDT Tue Aug 26 2014
.SHORT TERM...(Today and Tonight)
Issued at 401 AM CDT TUE AUG 26 2014
Early this morning a broad mid-level ridge remained anchored over
the southeastern quadrant of the U.S. with a deepening mid-level
trough over the Great Basin area. With this pattern in place,
southwesterly flow aloft prevailed across the central U.S. with
water vapor imagery showing a few weak embedded shortwaves
developing across Kansas and Nebraska early this morning. At the
surface, low pressure was in place with a fairly stationary boundary
across south central Kansas and extending into northeast Kansas,
essentially bisecting the forecast area. With the support of a
stronger embedded shortwave, an MCS quickly developed across eastern
Nebraska early this morning and persisted through the overnight
hours as it was supported by the low-level jet and decent isentropic
lift. A weaker shortwave was noted across central Kansas, which
sparked a cluster of showers and thunderstorms overnight. However,
this activity was gradually weakening as outflow boundaries
continued to gust out ahead of the storms. As a result, local radar
showed several outflow boundaries situated across the region from
this activity. Mid-level clouds were in place over eastern Kansas,
providing better insolation and keeping temperatures more mild in
the mid/upper 70s. However, cooler conditions were noted over north
central Kansas as a result of the rain-cooled air, bringing
temperatures down into the mid 60s to low 70s.
The precipitation forecast continues to be a challenge in the short
term as we continue to deal with a stationary boundary over the
forecast area, passing weak embedded shortwaves, and lingering
outflow boundaries from overnight convection. The HRRR has been
handling the morning activity fairly well and shows the
precipitation lifting northward and becoming more focused near the
Kansas/Nebraska border before finally diminishing by mid to late
morning. However, there is uncertainty with whether or not any
additional convection will develop near the stationary boundary
and/or along any of the lingering outflow boundaries this afternoon. While a
few models are hinting at this redevelopment, they vary with regards
to the location of the precipitation. At this time, have increasing
PoPs during the afternoon hours into this evening across the
northern half of the forecast area. A stronger embedded shortwave
may once again track across north central Kansas into Nebraska late
tonight, supporting overnight convection primarily near the
Kansas/Nebraska border. While the potential for severe weather is
low, cannot rule out some strong wind gusts and locally heavy rain.
With this set-up in place, temperatures are also a challenge for
today as they will be greatly affected by any precipitation that
develops. In general, expect slightly cooler conditions across far
northern Kansas where precipitation may linger this morning and
potentially redevelop this afternoon. However, conditions may still
heat up across east central Kansas as this region may stay mostly
dry through the day. Afternoon highs in this area could reach into
the mid/upper 90s with heat indices reaching into the 100 to 103
degree range. This area may be close to heat advisory criteria, but
due to the uncertainty in the development of any afternoon
convection, have not issued one at this time but will need to
closely monitor through the day. Low temperatures tonight are
expected to drop into the upper 60s north to low 70s south.
.LONG TERM...(Wednesday through Monday)
Issued at 401 AM CDT TUE AUG 26 2014
Wednesday will likely see an ongoing MCS across Nebraska as models
focus on areas north of the Kansas border. Expect outflow boundaries
to be present across the northern CWA and possibly some ongoing
convection through the morning hours. Left over boundaries may also
be a focus for additional development in the afternoon as well.
Wednesday night into Thursday energy will eject out of the Rockies
trough across western Kansas and Nebraska this along with the low
level jet should fuel yet another MCS across the Plains mainly
across Nebraska. Western Kansas convection will move east into the
CWA Wednesday night and into Thursday morning. Additionally Nebraska
MCS could also clip the northern counties and have maintained
highest probabilities of showers and thunderstorms to the north of
I-70.
The models slowly move the upper trough across the Rockies and
Plains as it is cut off from the westerlies. The 00Z GFS and the 00Z
ECMWF continue to be in agreement with the speed of the trough
through the end of the week while the GFS ensemble mean is just a
tad faster as is the GEM with the passage of the trough axis across
eastern Kansas and western Missouri. Front should move into central
Kansas Thursday night into Friday then progress slowly across
eastern Kansas through Saturday. The front will be a focus for
convection as well as locally heavy rainfall as precipitable water
values of 1.50 to 2.00 inches will be in place. Good moisture
transport will continue each night across the plains as the low
level jet increases and larger scale ascent increases with the
approach of the upper trough. Some convection may linger into Sunday
in the east with another chance of thunderstorms late Sunday night
and into Monday as a wave moves through the Zonal flow across the
Central Plains. Temperatures will gradually cool by the end of the
week with Wednesday being the warmest day especially south of I-70.
Near normal temperatures in the upper 80s to lower 90s are expected
from Thursday through Monday.
&&
.AVIATION...(For the 06Z TAFs through 06Z Tuesday Night)
Issued at 1143 PM CDT MON AUG 25 2014
Will maintain a dry/VFR forecast for THE KTOP/KFOE terminals through
the period as confidence on either of these terminal being
directly affected by convection is low. However...feel that
decaying MCS may get closer to KMHK behind outflow boundary so
will maintain VCTS at KMHK until MCS is expected to dissipate by
09z. As convection continues to rapidly develop to the north in NE...
confidence is increasing of another outflow boundary bringing winds
back around to the northeast late this morning before veering to
the southeast aft 18z in return flow. With little or no precip
expected in the terminals...will maintain only vfr mid and high
clouds and no vsby restrictions.
&&
.TOP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...Hennecke
LONG TERM...53
AVIATION...63
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
347 AM CDT TUE AUG 26 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 148 AM CDT TUE AUG 26 2014
NAM AND GFS WERE BOTH IN GOOD AGREEMENT WITH AN UPPER LEVEL
TROUGH MOVING ACROSS NEW MEXICO TODAY AND THEN ACROSS WESTERN
KANSAS DURING THE OVERNIGHT HOURS. AS THIS UPPER LEVEL DISTURBANCE
APPROACHESTODAY AN AREA OF LOW PRESSURE WILL DEVELOP ACROSS
SOUTHEAST COLORADO AND A SURFACE BOUNDARY LOCATED NEAR THE
OKLAHOMA BORDER EARLIER THIS MORNING WILL BEGIN TO LIFT NORTH
ACROSS SOUTHWEST KANSAS. BY LATE DAY THIS SURFACE BOUNDARY IS
EXPECTED TO EXTEND FROM SOUTHEAST COLORADO INTO NORTH CENTRAL
KANSAS WITH AN AREA OF HIGHER LOW LEVEL DEWPOINTS POOLING JUST
NORTH/WEST OF THIS SURFACE BOUNDARY. ALTHOUGH MODELS DO DISAGREE
ON JUST HOW FAR NORTH THIS BOUNDARY WILL BE BY LATE DAY THE NAM
AND GFS DO AGREE THAT LATE DAY SURFACE BASED CAPES ALONG AND NORTH
OF THIS BOUNDARY WILL RANGE FROM 1500 TO 3000 J/KG. GIVEN THE
LOCATION OF THE SURFACE BOUNDARY, LOW LEVEL MOISTURE, AND
AFTERNOON INSTABILITY WILL CONTINUE TO FAVOR THE HIGHER CHANCES
FOR CONVECTION TO BE LOCATED NORTHWEST OF AN ELKHART TO RUSH
CENTER AREAS LATE TODAY AND EARLY TONIGHT. 0-6KM SHEAR HOWEVER
FORECAST TO BE LESS THAN 20KNOTS SO A FEW STRONG PULSE
THUNDERSTORMS MAY BE POSSIBLE LATE DAY, SEVERE THUNDERSTORMS ARE
NOT ANTICIPATED AT THIS TIME BUT SMALL HAIL AND WIND GUSTS UP TO
50 MPH WILL BE POSSIBLE ACROSS FAR WESTERN KANSAS AND NORTH
CENTRAL KANSAS. TEMPERATURES TODAY WILL ONCE AGAIN CLIMB BACK INTO
THE MID TO UPPER 90S BASED ON 00Z 850MB TO 700MB TEMPERATURES FROM
THE NAM AND GFS.
AS AN UPPER LEVEL DISTURBANCE CROSSES WESTERN KANSAS EARLY
TONIGHT THE THUNDERSTORMS ACROSS WESTERN AND NORTH CENTRAL KANSAS
WILL INCREASE IN COVERAGE AND CONTINUE. AT THIS TIME WILL PLACE
THE HIGHER CHANCES JUST AHEAD OF THIS UPPER WAVE AS IT CROSSES
WESTERN KANSAS BETWEEN 03Z WEDNESDAY AND 09Z WEDNESDAY.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 343 AM CDT TUE AUG 26 2014
AN UPPER LEVEL LOW CURRENTLY ACROSS THE DESERT SOUTHWEST WILL TREK
EASTWARD ACROSS THE CENTRAL ROCKIES WEDNESDAY AND THURSDAY THEN
THROUGH THE CENTRAL PLAINS FRIDAY INTO SATURDAY. THIS FEATURE WILL
INCREASE LIFT ACROSS THE AREA AS IT APPROACHES AND PASSES
OVERHEAD. MID LEVELS OF THE ATMOSPHERE WILL GENERALLY BE SATURATED
THROUGH SATURDAY ALLOWING MOSTLY CLOUDY SKIES TO BE OBSERVED
ACROSS WESTERN KANSAS. TOWARDS THE SURFACE, AN AREA OF LOW
PRESSURE WILL BE POSITIONED SOMEWHERE ACROSS NORTHWEST KANSAS,
NORTHEAST COLORADO, AND SOUTHWEST NEBRASKA THROUGH WEDNESDAY NIGHT
WITH A FRONTAL BOUNDARY EXTENDING EASTWARD ACROSS THE KS/NE LINE.
A COLD FRONT IS THEN PROGGED TO MOVE THROUGH THE AREA THURSDAY
INTO THURSDAY NIGHT BEFORE STALLING OUT ACROSS CENTRAL KANSAS,
WESTERN OKLAHOMA, AND WESTERN TEXAS ON FRIDAY INTO SATURDAY. WITH
THESE FEATURES IN PLACE, THUNDERSTORM CHANCES WILL GENERALLY BE IN
THE FORECAST THROUGH FRIDAY WITH THE STORM EXITING THE AREA FRIDAY
NIGHT INTO EARLY SATURDAY MORNING. THE BEST CHANCES OF
PRECIPITATION LOOK TO BE WEDNESDAY NIGHT WHEN THE LIFT IS
STRONGEST THEN AGAIN ON FRIDAY AS MOISTURE WRAPS AROUND THE
AFOREMENTIONED LOW. THE REMAINDER OF THE EXTENDED FORECAST LOOKS
DRY AS HIGH PRESSURE BUILDS INTO THE AREA BRINGING PARTLY CLOUDY
SKIES. AS FOR TEMPERATURES, HIGHS WEDNESDAY LOOK TO TOP OUT IN THE
LOWER TO MID 90S WITH 80S EXPECTED THURSDAY THROUGH SATURDAY.
HIGHS THEN REACH INTO THE LOWER 90S SUNDAY INTO MONDAY. LOWS LOOK
TO RANGE FROM THE LOWER 60S ACROSS WEST CENTRAL KANSAS TO LOWER
70S ACROSS SOUTH CENTRAL KANSAS WEDNESDAY MORNING WITH LOWS IN THE
60S THURSDAY MORNING THROUGH MONDAY MORNING.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT)
ISSUED AT 1222 AM CDT TUE AUG 26 2014
LATEST RADAR TREND SHOWING CONVECTION TAPERING OFF ACROSS
SOUTHWEST KANSAS AS OF 05Z. THIS WAS CONSISTENT WITH THE LATEST
NAM AND HRRR SOLUTION. THESE MODELS ALSO INDICATED THE OVERNIGHT
CONVECTION EXPECTED ACROSS NORTHWEST AND NORTH CENTRAL KANSAS WILL
STAY NORTH/NORTHWEST OF THE HAYS AREA. BUFR SOUNDINGS INDICATING
CLOUD COVER WILL BE AT OR ABOVE THE 10000 FT AGL OVERNIGHT AND
EARLY TUESDAY SO VFR CONDITIONS ARE EXPECTED. EASTERLY WINDS AT
10KNOTS OR LESS OVERNIGHT WILL GRADUALLY VEER TO THE SOUTHEAST AND
INCREASE BY LATE MORNING TO AROUND 15 KNOTS.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 95 69 92 69 / 20 30 60 40
GCK 93 67 90 67 / 30 50 40 50
EHA 93 66 89 65 / 40 50 40 40
LBL 94 68 92 68 / 20 20 40 40
HYS 93 68 91 69 / 30 50 60 70
P28 99 73 96 72 / 10 10 30 40
&&
.DDC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...BURGERT
LONG TERM...HOVORKA_42
AVIATION...BURGERT
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
153 AM CDT TUE AUG 26 2014
...UPDATED SHORT TERM DISCUSSION...
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 148 AM CDT TUE AUG 26 2014
NAM AND GFS WERE BOTH IN GOOD AGREEMENT WITH AN UPPER LEVEL
TROUGH MOVING ACROSS NEW MEXICO TODAY AND THEN ACROSS WESTERN
KANSAS DURING THE OVERNIGHT HOURS. AS THIS UPPER LEVEL DISTURBANCEAPPROACHES
TODAY AN AREA OF LOW PRESSURE WILL DEVELOP ACROSS SOUTHEAST
COLORADO AND A SURFACE BOUNDARY LOCATED NEAR THE OKLAHOMA BORDER
EARLIER THIS MORNING WILL BEGIN TO LIFT NORTH ACROSS SOUTHWEST
KANSAS. BY LATE DAY THIS SURFACE BOUNDARY IS EXPECTED TO EXTEND
FROM SOUTHEAST COLORADO INTO NORTH CENTRAL KANSAS WITH AN AREA OF
HIGHER LOW LEVEL DEWPOINTS POOLING JUST NORTH/WEST OF THIS SURFACE
BOUNDARY. ALTHOUGH MODELS DO DISAGREE ON JUST HOW FAR NORTH THIS
BOUNDARY WILL BE BY LATE DAY THE NAM AND GFS DO AGREE THAT LATE
DAY SURFACE BASED CAPES ALONG AND NORTH OF THIS BOUNDARY WILL
RANGE FROM 1500 TO 3000 J/KG. GIVEN THE LOCATION OF THE SURFACE
BOUNDARY, LOW LEVEL MOISTURE, AND AFTERNOON INSTABILITY WILL
CONTINUE TO FAVOR THE HIGHER CHANCES FOR CONVECTION TO BE LOCATED
NORTHWEST OF AN ELKHART TO RUSH CENTER AREAS LATE TODAY AND EARLY
TONIGHT. 0-6KM SHEAR HOWEVER FORECAST TO BE LESS THAN 20KNOTS SO A
FEW STRONG PULSE THUNDERSTORMS MAY BE POSSIBLE LATE DAY, SEVERE
THUNDERSTORMS ARE NOT ANTICIPATED AT THIS TIME BUT SMALL HAIL AND
WIND GUSTS UP TO 50 MPH WILL BE POSSIBLE ACROSS FAR WESTERN KANSAS
AND NORTH CENTRAL KANSAS. TEMPERATURES TODAY WILL ONCE AGAIN CLIMB
BACK INTO THE MID TO UPPER 90S BASED ON 00Z 850MB TO 700MB
TEMPERATURES FROM THE NAM AND GFS.
AS AN UPPER LEVEL DISTURBANCE CROSSES WESTERN KANSAS EARLY
TONIGHT THE THUNDERSTORMS ACROSS WESTERN AND NORTH CENTRAL KANSAS
WILL INCREASE IN COVERAGE AND CONTINUE. AT THIS TIME WILL PLACE
THE HIGHER CHANCES JUST AHEAD OF THIS UPPER WAVE AS IT CROSSES
WESTERN KANSAS BETWEEN 03Z WEDNESDAY AND 09Z WEDNESDAY.
.LONG TERM...(TUESDAY NIGHT THROUGH MONDAY)
ISSUED AT 304 PM CDT MON AUG 25 2014
AN UPPER LEVEL LOW OVER THE WESTERN UNITED STATES WILL SLOWLY
PROGRESS EASTWARD AND PASS ACROSS WESTERN KANSAS BY FRIDAY. AHEAD
OF THIS FEATURE, LOW LEVEL MOISTURE WILL BE PLENTIFUL AND 700MB
TEMPERATURES WILL COOL TO AROUND 10C. THE BEST CHANCE OF THE MORE
WIDESPREAD AND HEAVY RAINFALL THROUGH WEDNESDAY WILL BE ALONG AND
NORTH OF A STALLED OUT FRONTAL BOUNDARY ACROSS NORTHERN KANSAS AND
POINTS NORTHWARD FROM THERE WHERE LOW TO MID LEVEL MOISTURE WILL BE
PLENTIFUL. MID LEVEL TEMPERATURES ARE PROGGED TO COOL TO AROUND
10C THROUGH WEDNESDAY ACROSS SOUTHWEST KANSAS SO THAT ISOLATED TO
SCATTERED THUNDERSTORMS ARE POSSIBLE EVEN SOUTH OF THE FRONT. BY
THURSDAY AND FRIDAY AS THE UPPER LEVEL SYSTEM GETS CLOSER AND MID
LEVEL TEMPERATURES DROP FURTHER, THE CHANCE FOR WIDESPREAD
THUNDERSTORM ACTIVITY WILL INCREASE ACROSS SOUTHWESTERN KANSAS,
ALONG WITH COOLER TEMPERATURES. HIGH TEMPERATURES WILL STILL BE IN
THE LOWER 90S ON WEDNESDAY, AND THEN FALL INTO THE 80S BY THURSDAY
AND FRIDAY AS CLOUD COVER AND PRECIPITATION INCREASE. THE ECMWF IS
SLOWER TO BRING THIS SYSTEM THROUGH WESTERN KANSAS WITH THE GFS
THE MOST PROGRESSIVE. BUT IT DOES APPEAR THAT THE SIGNIFICANT
RAINFALL WILL BE OVER BY FRIDAY NIGHT. A SLOW WARMING TREND CAN BE
EXPECTED THEREAFTER AS THE MID LEVEL FLOW BECOMES MORE WESTERLY
ACROSS THE ROCKIES, WITH LEE TROUGHING BECOMING ESTABLISHED.
THUNDERSTORM ACTIVITY MAY INCREASE AGAIN SOMETIME EARLY NEXT WEEK
AS LOW LEVEL MOISTURE SURGES NORTH FROM THE GULF OF MEXICO ALONG
THE SOUTHERN EDGE OF THE WESTERLIES. BUT MID LEVEL TEMPERATURES
WILL ONCE AGAIN BECOME QUITE WARM SO THAT MID LEVEL CAPPING MAY
SUPPRESS CONVECTION.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT)
ISSUED AT 1222 AM CDT TUE AUG 26 2014
LATEST RADAR TREND SHOWING CONVECTION TAPERING OFF ACROSS
SOUTHWEST KANSAS AS OF 05Z. THIS WAS CONSISTENT WITH THE LATEST
NAM AND HRRR SOLUTION. THESE MODELS ALSO INDICATED THE OVERNIGHT
CONVECTION EXPECTED ACROSS NORTHWEST AND NORTH CENTRAL KANSAS WILL
STAY NORTH/NORTHWEST OF THE HAYS AREA. BUFR SOUNDINGS INDICATING
CLOUD COVER WILL BE AT OR ABOVE THE 10000 FT AGL OVERNIGHT AND
EARLY TUESDAY SO VFR CONDITIONS ARE EXPECTED. EASTERLY WINDS AT
10KNOTS OR LESS OVERNIGHT WILL GRADUALLY VEER TO THE SOUTHEAST AND
INCREASE BY LATE MORNING TO AROUND 15 KNOTS.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 95 69 92 68 / 30 30 30 40
GCK 93 67 90 66 / 40 40 40 50
EHA 93 66 88 65 / 40 30 40 40
LBL 94 68 92 67 / 40 30 40 40
HYS 93 68 91 67 / 40 50 50 60
P28 99 73 96 71 / 10 10 30 30
&&
.DDC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...BURGERT
LONG TERM...FINCH
AVIATION...BURGERT
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
1225 AM CDT TUE AUG 26 2014
...UPDATED AVIATION DISCUSSION...
.SHORT TERM...(THIS EVENING THROUGH TUESDAY)
ISSUED AT 241 PM CDT MON AUG 25 2014
A COLD FRONT HAS SAGGED SOUTHWARD AND AUGMENTED BY EARLIER
CONVECTION WAS LOCATED BETWEEN GARDEN CITY AND HAYS. THIS BOUNDARY
IS FORECAST TO BE NEARLY STATIONARY INTO THIS EVENING. THE BOUNDARY
WILL SERVE AS A FOCUS FOR LATE AFTERNOON AND OVERNIGHT
THUNDERSTORMS. MODERATE INSTABILITY WITH CAPE FORECAST OF AROUND
2500 J/KG NEAR AND NORTH OF THIS FRONTAL BOUNDARY. COULD SEE SOME
STRONG OUTFLOW WINDS OF 50 MPH OR HIGHER AND SOME SMALL HAIL. A FEW
STORMS COULD APPROACH NEAR SEVERE LIMITS INTO THE EVENING. WEAK MID
LEVEL WIND FIELDS AND SHEAR SHOULD BE ENOUGH TO KEEP MOST STORMS
BELOW SEVERE LIMITS. THE BEST POTENTIAL FOR STORMS WILL BE GENERALLY
NORTH OF HIGHWAY 96 AND INTO THE I-70 CORRIDOR. ALSO SOME POTENTIAL
FOR LOCALLY HEAVY RAINFALL IN THOSE AREAS IF THUNDERSTORMS CAN TRAIN
OVER THE SAME AREAS. WILL KEEP SMALL POPS GOING SOUTH OF THE
BOUNDARY INTO THE OVERNIGHT PERIODS. SOUTHEAST WINDS WILL BECOME
LIGHT AND VARIABLE TOWARDS MORNING WITH OUTFLOWS CAUSING THE FRONT
TO SAG MORE SOUTH INTO SOUTHWEST KANSAS. OVERNIGHT LOWS WILL BE MILD
IN THE MID TO UPPER 60S. PARTS OF SOUTH CENTRAL KANSAS NEAR SAINT
JOHN TO COLDWATER AND EAST MAY NOT SEE ANY STORMS AND BE WARMER
OVERNIGHT AROUND 70.
FOR TUESDAY, WILL CONTINUE WITH 20 TO 30 PERCENT CHANCES FOR
THUNDERSTORMS, MAINLY IN THE AFTERNOON, GENERALLY WEST OF A LARNED
TO COLDWATER LINE. THUNDERSTORMS MAY AGAIN FORM WHERE ANY BOUNDARIES
ARE LEFT OVER. WEAKER INSTABILITY AND WIND FIELDS SHOULD PRECLUDE
SEVERE THUNDERSTORM CHANCES. WINDS WILL BE LIGHT AND VARIABLE THEN
BECOMING SOUTHEASTERLY 15 TO 20 MPH UNDER PARTLY CLOUDY SKIES. HIGHS
WILL BE COOLER WITH MOIST UPSLOPE FLOW AND RESIDUAL CLOUDINESS
MAINLY EAST OF DODGE CITY. HIGHS WILL RANGE FROM THE LOW TO MID 90S
WEST OF DODGE CITY TO THE MID AND UPPER 90S EAST.
.LONG TERM...(TUESDAY NIGHT THROUGH MONDAY)
ISSUED AT 304 PM CDT MON AUG 25 2014
AN UPPER LEVEL LOW OVER THE WESTERN UNITED STATES WILL SLOWLY
PROGRESS EASTWARD AND PASS ACROSS WESTERN KANSAS BY FRIDAY. AHEAD
OF THIS FEATURE, LOW LEVEL MOISTURE WILL BE PLENTIFUL AND 700MB
TEMPERATURES WILL COOL TO AROUND 10C. THE BEST CHANCE OF THE MORE
WIDESPREAD AND HEAVY RAINFALL THROUGH WEDNESDAY WILL BE ALONG AND
NORTH OF A STALLED OUT FRONTAL BOUNDARY ACROSS NORTHERN KANSAS AND
POINTS NORTHWARD FROM THERE WHERE LOW TO MID LEVEL MOISTURE WILL BE
PLENTIFUL. MID LEVEL TEMPERATURES ARE PROGGED TO COOL TO AROUND
10C THROUGH WEDNESDAY ACROSS SOUTHWEST KANSAS SO THAT ISOLATED TO
SCATTERED THUNDERSTORMS ARE POSSIBLE EVEN SOUTH OF THE FRONT. BY
THURSDAY AND FRIDAY AS THE UPPER LEVEL SYSTEM GETS CLOSER AND MID
LEVEL TEMPERATURES DROP FURTHER, THE CHANCE FOR WIDESPREAD
THUNDERSTORM ACTIVITY WILL INCREASE ACROSS SOUTHWESTERN KANSAS,
ALONG WITH COOLER TEMPERATURES. HIGH TEMPERATURES WILL STILL BE IN
THE LOWER 90S ON WEDNESDAY, AND THEN FALL INTO THE 80S BY THURSDAY
AND FRIDAY AS CLOUD COVER AND PRECIPITATION INCREASE. THE ECMWF IS
SLOWER TO BRING THIS SYSTEM THROUGH WESTERN KANSAS WITH THE GFS
THE MOST PROGRESSIVE. BUT IT DOES APPEAR THAT THE SIGNIFICANT
RAINFALL WILL BE OVER BY FRIDAY NIGHT. A SLOW WARMING TREND CAN BE
EXPECTED THEREAFTER AS THE MID LEVEL FLOW BECOMES MORE WESTERLY
ACROSS THE ROCKIES, WITH LEE TROUGHING BECOMING ESTABLISHED.
THUNDERSTORM ACTIVITY MAY INCREASE AGAIN SOMETIME EARLY NEXT WEEK
AS LOW LEVEL MOISTURE SURGES NORTH FROM THE GULF OF MEXICO ALONG
THE SOUTHERN EDGE OF THE WESTERLIES. BUT MID LEVEL TEMPERATURES
WILL ONCE AGAIN BECOME QUITE WARM SO THAT MID LEVEL CAPPING MAY
SUPPRESS CONVECTION.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT)
ISSUED AT 1222 AM CDT TUE AUG 26 2014
LATEST RADAR TREND SHOWING CONVECTION TAPERING OFF ACROSS
SOUTHWEST KANSAS AS OF 05Z. THIS WAS CONSISTENT WITH THE LATEST
NAM AND HRRR SOLUTION. THESE MODELS ALSO INDICATED THE OVERNIGHT
CONVECTION EXPECTED ACROSS NORTHWEST AND NORTH CENTRAL KANSAS WILL
STAY NORTH/NORTHWEST OF THE HAYS AREA. BUFR SOUNDINGS INDICATING
CLOUD COVER WILL BE AT OR ABOVE THE 10000 FT AGL OVERNIGHT AND
EARLY TUESDAY SO VFR CONDITIONS ARE EXPECTED. EASTERLY WINDS AT
10KNOTS OR LESS OVERNIGHT WILL GRADUALLY VEER TO THE SOUTHEAST AND
INCREASE BY LATE MORNING TO AROUND 15 KNOTS.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 69 92 68 87 / 30 30 40 40
GCK 67 90 66 86 / 40 40 50 40
EHA 66 88 65 84 / 30 40 40 40
LBL 68 92 67 87 / 30 40 40 40
HYS 68 91 67 86 / 50 50 60 40
P28 73 96 71 91 / 10 30 30 40
&&
.DDC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...KRUSE
LONG TERM...FINCH
AVIATION...BURGERT
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
501 AM EDT TUE AUG 26 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 501 AM EDT TUE AUG 26 2014
PER WATER VAPOR IMAGERY AND RUC ANALYSIS...VIGOROUS SHORTWAVE THAT
WAS MOVING INTO SRN MANITOBA 24HRS AGO IS NOW MUCH WEAKER AND
TRACKING THRU NRN ONTARIO. ASSOCIATED COLD FRONT SWEPT ACROSS UPPER
MI DURING THE NIGHT...USHERING IN MUCH DRIER AIR. SFC DWPTS THAT
WERE IN THE 60S TO AROUND 70F ARE NOW DOWN IN THE MORE COMFORTABLE
50S AT NEARLY ALL LOCATIONS. UPSTREAM...QUITE A BIT OF CLOUD COVER IS
NOTED ACROSS THE NRN HALF OF MN...AND THERE HAVE EVEN BEEN A FEW
-SHRA/SPRINKLES IN NE MN. IN THE LAST FEW HRS...THE CLOUDS HAVE BEEN
THINNING OUT...AND RECENTLY THE CLOUDS HAVE SPREAD INTO WRN UPPER
MI. THESE CLOUDS ARE SITUATED IN THE 850MB THERMAL TROF WHICH HAS
850MB TEMPS AS LOW AS 4-5C OVER FAR NRN MN.
TODAY...850MB TROF SHIFTS INTO THE UPPER GREAT LAKES. WITH ONSET OF
DAYTIME HEATING COINCIDING WITH ARRIVAL OF THERMAL TROF...THERE
SHOULD BE AN EXPANSION OF SCT/BKN CU/STRATOCU FOR A TIME...
ESPECIALLY ACROSS THE N. DURING THE MID AND LATE AFTN...THE CLOUDS
SHOULD BEGIN TO DISSIPATE. FCST SOUNDINGS SUPPORT MAX TEMPS IN THE
UPPER 60S TO MID 70S...WARMEST SOUTH CENTRAL. WILL BE A BIT COOLER
WHERE WINDS ARE OFF LAKE SUPERIOR.
TONIGHT...SFC HIGH PRES BUILDS INTO THE WRN GREAT LAKES. HOWEVER...
SHORTWAVE TROF NOW OVER SASKATCHEWAN/MT IS FCST TO SHIFT E...
REACHING THE UPPER GREAT LAKES BY 12Z WED. SOME MODELS SHOW LIGHT
PCPN STREAKING E INTO WI AND EVEN INTO UPPER MI. INITIALLY...PCPN
DEVELOPMENT OUT OVER THE NRN PLAINS APPEARS TIED TO RIGHT ENTRANCE
OF JET STREAK ACROSS THE FAR NRN PLAINS. HOWEVER...WITH THE JET
TRANSLATING E OVER THE UPPER GREAT LAKES...JET FORCING WILL BE S OF
THE FCST AREA TONIGHT. IN ADDITION...LITTLE/NO DEEP LAYER FORCING IS
NOTED WITH SHORTWAVE...AND LOW-LEVELS ARE DRYING OUT TODAY. SO...IF
PCPN DOES MANAGE TO STREAK INTO THE AREA...THE LIGHT PCPN WOULD
LIKELY DRY UP BEFORE MAKING IT TO THE GROUND. THUS...NO MENTION OF
PCPN WAS INCLUDED IN FCST TONIGHT. AN INCREASE IN CLOUDS WILL KEEP
TEMPS FROM FALLING AS MUCH AS THEY COULD. OPTED FOR THE MIDDLE
GROUND OF AVBL GUIDANCE...RESULTING IN MIN TEMPS MOSTLY IN THE UPPER
40S/LWR 50S.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 346 AM EDT TUE AUG 26 2014
A SHORTWAVE WILL BE SLIDING EAST ACROSS THE CENTRAL/EASTERN CWA TO
START THE LONG TERM PERIOD WITHIN THE WEST-NORTHWEST FLOW ALOFT.
THERE IS A LITTLE POCKET OF MOISTURE BETWEEN 700-500MB ASSOCIATED
WITH THIS WAVE THAT WILL TRY TO KICK OFF SOME SHOWERS OVER THE
EASTERN CWA FOR THE FIRST COUPLE HOURS ON WEDNESDAY MORNING. WITH
DRY AIR BELOW 700MB DUE TO HIGH PRESSURE CENTERED NEAR DULUTH AT
12Z WEDNESDAY...THINK ANY PRECIPITATION THAT OCCURS WILL EVAPORATE
BEFORE REACHING THE SURFACE. BEHIND THIS WAVE...UPPER RIDGING WILL
DEVELOP AND ALLOW THE HIGH TO SHIFT EAST ACROSS THE CWA THROUGH
THURSDAY MORNING. THIS DRY AIR WILL LEAD TO MOSTLY CLEAR SKIES
ACROSS MUCH OF THE CWA...BUT THERE COULD BE SOME DIURNAL CLOUD
DEVELOPMENT WEDNESDAY AFTERNOON (INLAND AND TOWARDS WISCONSIN
BORDER) AFTER THE MID CLOUDS DEPART DURING THE MORNING. HIGHS WILL
BE BELOW NORMAL ON WEDNESDAY SINCE 850MB TEMPS IN THE MODELS ARE
AVERAGING AROUND 6-7C AND KEEPING HIGHS IN THE MID-UPPER 60S FOR
MOST LOCATIONS. LOWS WEDNESDAY NIGHT COULD GET CHILLY WITH THE
LIGHT WINDS...CLEAR SKIES...AND PWAT VALUES ABOUT 50 PERCENT OF
NORMAL. TRENDED LOWS DOWN INTO THE LOWER 40S OVER THE INTERIOR
LOCATIONS...AND EVEN HAVE SOME UPPER 30S FOR THE TRADITIONAL COLD
RAWS SITES.
THE AREA OF HIGH PRESSURE WILL DRIFT TO THE EAST ON THURSDAY AS THE
FIRST OF A SERIES OF SHORTWAVES LIFTS NORTHEAST OUT OF THE CENTRAL
ROCKIES/PLAINS THURSDAY AFTERNOON INTO THURSDAY NIGHT. AS HAS BEEN
THE CASE FOR THE LAST COUPLE DAYS...SEEMS LIKE BEST OPPORTUNITY FOR
RAIN WILL BE OVER THE SOUTHEAST HALF OF THE CWA. THESE SHOWERS
COULD LINGER INTO FRIDAY OVER THE SAME AREA BEFORE THE NEXT WAVE
SLIDES NORTHEAST TOWARDS THE AREA ON FRIDAY NIGHT. ONCE
AGAIN...BEST CHANCES WILL BE OVER THE SOUTHEAST PART OF THE
AREA...BUT LIKELY MORE CONFINED TO NEAR THE LAKE MICHIGAN
SHORELINE. WHILE THAT WAVE IS MOVING THROUGH...A WEAK SURFACE
TROUGH WILL SLOWLY DROP SOUTHEAST ACROSS THE CWA ON SATURDAY. THINK
PRECIP CHANCES WITH THIS PASSING TROUGH WILL BE LIMITED DUE TO
SHALLOW MOISTURE AND LIMITED UPPER LEVEL SUPPORT...THUS WILL KEEP
POPS FOR MOST AREAS IN THE SLIGHT CHANCE CATEGORY. BEHIND THAT
TROUGH...A HIGH PRESSURE RIDGE WILL MOVE OVER THE CWA SATURDAY
NIGHT AND REMAIN THROUGH SUNDAY NIGHT...AS THE PARENT HIGH SLIDES
SOUTHEAST ACROSS NORTHERN ONTARIO.
A STRONGER UPPER TROUGH WILL APPROACH THE AREA FOR THE FIRST PART
OF NEXT WEEK. A LOW PRESSURE SYSTEM ASSOCIATED WITH THIS UPPER
TROUGH WILL BE MOVING THROUGH SOUTHERN CANADA AND ALLOW SOUTHERLY
FLOW TO INCREASE OVER THE AREA SUNDAY NIGHT INTO MONDAY. THIS WILL
LEAD TO ABOVE NORMAL TEMPERATURES ON MONDAY AHEAD OF THE COLD FRONT
THAT MOVES THROUGH MONDAY NIGHT INTO TUESDAY MORNING. WILL SHOW
INCREASING CHANCES FOR RAIN MONDAY INTO MONDAY NIGHT AS THE COLD
FRONT PASSES THROUGH.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT)
ISSUED AT 129 AM EDT TUE AUG 26 2014
WITH DRIER AIR MOVING INTO THE AREA...VFR CONDITIONS WILL PREVAIL
THROUGH THE FCST PERIOD. WEST WINDS WILL REMAIN GUSTY AT
KCMX...ESPECIALLY AGAIN THIS MORNING WITH DAYTIME HEATING/MIXING.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 501 AM EDT TUE AUG 26 2014
EXPECT WESTERLY WINDS AS HIGH AS 15-25KT OVER MUCH OF LAKE SUPERIOR
TODAY...RESULTING FROM PRES GRADIENT BTWN LOW PRES WELL OFF TO THE
NE AND HIGH PRES APPROACHING FROM THE W. AS THE HIGH SETTLES OVER
THE UPPER GREAT LAKES LATER TONIGHT THRU EARLY THU...WINDS WILL DROP
OFF TO MOSTLY UNDER 15KT. ALTHOUGH THE HIGH PRES DEPARTS THU...WINDS
SHOULD REMAIN UNDER 20KT FRI/SAT EVEN WITH TROF DROPPING ACROSS THE
AREA EARLY SAT.
&&
.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 FORKS ND
404 AM CDT TUE AUG 26 2014
.SHORT TERM...(TODAY THROUGH WEDNESDAY)
ISSUED AT 345 AM CDT TUE AUG 26 2014
TODAY...SURFACE HIGH PRESSURE CONTINUES TO PRESS OVER THE AREA
PRODUCING LIGHT WEST TO NORTHWEST FLOW...DRYING CONDITIONS AND
UNSEASONABLY COOL TEMPERATURES. RESIDUAL LOW CLOUDS ACROSS
NORTHERN MINNESOTA SHOULD SHIFT EASTWARD THROUGH THE MORNING AS
THE PARENT LOW PRESSURE SYSTEM CONTINUES ITS FAST BREAK ACROSS
NORTHERN ONTARIO AND JAMES BAY. EXPECT GENERALLY FAIR SKIES ACROSS
MOST OF THE AREA THROUGH MIDDAY TODAY...WITH INCREASING MIDDLE TO
LOWER LEVEL MOISTURE MOVING FROM NCNTRL SD INTO SOUTHEAST ND AND
WESTCENTRAL MN THROUGH THE LATER AFTERNOON. AN ISOLATED SHOWER OR
TWO IS POSSIBLE LATE THIS AFTERNOON ACROSS FAR SOUTHERN PORTIONS
OF THE RED RIVER BASIN. FOR NOW...THE RUC SEEMS A BIT OVERLY
AGGRESSIVE WIT THIS FEATURE...WHILE HRRR AND NAM PREFER A SOMEWHAT
STRONGER SFC HIGH PRESSURE OVER NORTHERN MINNESOTA...KEEPING MOST
OF THE PRECIP THREAT WELL TO OUR SOUTH.
TONIGHT AND WEDNESDAY...A FLAT SURFACE RIDGE STAYS DRAPED FROM
THE WESTERN GREAT LAKES...AND ACROSS NORTH DAKOTA INTO EASTERN MT.
SOUTHERLY FLOW INCREASES THROUGH THE DAY ON WEDNESDAY PROMISING
SOME REBOUNDING TEMPERATURES...WHILE DEEP MOISTURE STAYS TRAPPED
FOR ANOTHER DAY BY A STATIONARY SURFACE BOUNDARY ACROSS SOUTHERN
SD AND NRN IA.
.LONG TERM...(WEDNESDAY NIGHT THROUGH MONDAY)
ISSUED AT 345 AM CDT TUE AUG 26 2014
WEDNESDAY NIGHT AND THURSDAY...INCREASING LOW LEVEL SOUTHERLY
FLOW FROM WEDNESDAY EVENING INTO THURSDAY COULD BRING A BAND OF
MOIST AIR THROUGH EASTERN SD INTO WESTCENTRAL MN...WITH SCT
THUNDERSTORMS BRUSHING AGAINST THE SOUTHEAST EDGE OF THE RED RIVER
BASIN. HAVE STUCK WITH THE NAM AND WITH WPC CONTINUITY IN KEEPING
THE FORECAST DRY FOR THIS PERIOD WHILE THE 00Z GFS HAS BEEN
SOMETHING OF THE WET OUTLIER SOLN.
FRIDAY THROUGH MONDAY...LOW AMPLITUDE LONG WAVE TROUGH OVER THE
GULF OF AK MOVES TO CENTRAL CANADA BY THE END OF THE PERIOD.
ESSENTIALLY ZONAL FLOW REMAINS ACROSS SOUTHERN CANADA AND THE
NORTHERN STATES THROUGH THE PERIOD. ZONAL PATTERN SHIFTS SLOWLY
SOUTH BY THE END OF THE PERIOD. GFS AND ECMWF WERE IN GOOD
AGREEMENT THROUGH 84 HOURS WITH THE UPPER AIR. HOWEVER WITH THE
SURFACE FEATURES THE GFS WAS FAST AT 84 HOURS. THE GFS REMAINS
FASTER THAN THE ECMWF AT DAY 7. WILL BLEND THE ECMWF AND THE GFS.
LITTLE CHANGE TO TEMPS....INCREASES TEMPS A DEGREE OR SO FOR FRI AND
DECREASE A DEGREE OR SO FOR SAT. NO CHANGE TO SUN AND MON.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT)
ISSUED AT 345 AM CDT TUE AUG 26 2014
MAINLY VFR CU DECK CONTINUES TO ERODE WITH SKIES HAVING SCATTERED
OUT TO THE WEST OF A GFK-FAR LINE. THROUGH THE EARLY MORNING
EXPECT CONTINUED DECREASE IN CLOUD COVER OVER THE RRV AND ACROSS
NORTHWEST MN... WITH LINGERING BROKEN CIGS OVER THE LAKE OF THE
WOODS AND RED LAKES REGION THROUGH MID MORNING. LATE AFTERNOON
WILL SEE INCREASING MID TO LOWER LEVEL CLOUDS ACROSS FAR SOUTHEAST
ND...WITH SCT VFR CIGS AND RAIN SHOWERS POSSIBLE THERE.
&&
.FGF WATCHES/WARNINGS/ADVISORIES...
ND...NONE.
MN...NONE.
&&
$$
SHORT TERM...GUST
LONG TERM...GUST/HOPPES
AVIATION...GUST
AREA FORECAST DISCUSSION
NWS BISMARCK ND
1158 PM CDT MON AUG 25 2014
.UPDATE...
ISSUED AT 1158 PM CDT MON AUG 25 2014
LATEST SUITE OF SATELLITE IMAGERY SHOWS LOW CLOUDS EXITING THE
JAMES RIVER VALLEY WITH A SMALLER AREA OF LOW CLOUDS IN SOUTHWEST
NORTH DAKOTA. HOWEVER THESE ARE BEING MASKED BY THE INFLUX OF MID
AND HIGH LEVEL MOISTURE ADVECTING IN FROM WYOMING AND WESTERN
SOUTH DAKOTA. THIS IS IN ADVANCE OF SHORTWAVE EJECTING OUT FROM
EASTERN IDAHO WHICH IS FORECAST TO SLIDE ACROSS SOUTHERN NORTH
DAKOTA TUESDAY. VERTICAL MOTION ASSOCIATED WITH THIS SHORTWAVE IN
TANDEM WITH THE RIGHT ENTRANCE REGION OF A 70KT H300 JET STREAK WILL
RESULT IN AN AREA OF LIGHT RAIN SHOWERS TO DEVELOP LATE TONIGHT
INTO THE DAY TUESDAY OVER SOUTHERN NORTH DAKOTA. THE CURRENT
GRIDDED FORECAST HAS THIS COVERED WELL. COOL OVERNIGHT LOW
TEMPERATURES IN THE LOWER 40S REMAINS ON TRACK.
UPDATE ISSUED AT 913 PM CDT MON AUG 25 2014
ONLY CHANGE TO FORECAST WAS TO KEEP CLOUD COVER OVER PORTIONS OF
CENTRAL INTO WESTERN NORTH DAKOTA IN A BIT LONGER THIS EVENING AS
IT HAS BE RELUCTANT TO DISSIPATE OVER SOME LOCATIONS.
OTHERWISE...GOING FORECAST IS IN GOOD SHAPE. UPDATES HAVE BEEN SENT.
UPDATE ISSUED AT 611 PM CDT MON AUG 25 2014
A FEW SPRINKLES ARE RELUCTANT TO DISSIPATE OVER NORTHWEST NORTH
DAKOTA SO WILL KEEP THEM IN THE FORECAST FOR ANOTHER COUPLE OF
HOURS. OTHERWISE...GOING FORECAST APPEARS IN GOOD SHAPE WITH CLOUD
COVER STARTING TO SLOWLY DISSIPATE. UPDATES HAVE BEEN SENT.
&&
.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 06Z TAFS THROUGH 06Z TUESDAY NIGHT)
ISSUED AT 1158 PM CDT MON AUG 25 2014
EXPECTING MAINLY VFR CIGS/VSBYS NEXT 24HR...HOWEVER AN AREA OF MVFR
CIGS IS POSITIONED IN SOUTHWEST NORTH DAKOTA AND WILL LIKELY INCLUDE
A TEMPO GROUP AT KDIK THROUGH 10Z TUESDAY. ONLY OTHER IMPACT WOULD
BE SOME PATCHY FOG NEAR KMOT...AND HAVE INCLUDED A VCFG FROM 10Z
TUESDAY THROUGH 15Z. SCATTERED RAIN SHOWERS ARE FORECAST ACROSS
SOUTHERN NORTH DAKOTA TUESDAY...WITH KDIK AND KBIS ON THE FAR
NORTHERN FRINGES OF THE PRECIPITATION. INCLUDED A VCSH AT KDIK BUT
NOT AT KBIS.
&&
.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.
&&
$$
UPDATE...KS
SHORT TERM...TWH
LONG TERM...JV
AVIATION...KS
HYDROLOGY...TWH
AREA FORECAST DISCUSSION...CORRECTED
NWS HOUSTON/GALVESTON TX
444 AM CDT TUE AUG 26 2014
.DISCUSSION...
MORNING SFC ANALYSIS SHOWS FAIRLY WEAK PRESSURE GRADIENT ACROSS
MUCH OF TX WITH MAINLY E/SE WINDS ALONG THE UPPER TX COAST. WATER
VAPOR IMAGERY SHOWS A SHORT WAVE TROUGH MOVING ACROSS THE N GULF
TOWARDS SE TX. THE 00Z SOUNDING FROM LCH SHOWED 2.4 INCHES OF
PRECIP WATER WHICH IS QUITE HIGH FOR THIS TIME OF YEAR BEING 2 STD
DEV FROM NORMAL. GOES PRECIP WATER SOUNDER DATA SHOWS AT LEAST
THIS MUCH MOISTURE OVER A LARGE PORTION OF THE AREA. THIS BROAD
AREA OF DEEP MOISTURE EXTENDS FROM INLAND AREAS TO WELL OFF THE
COAST. SHORT RANGE MODELS ADVECT MUCH MORE MOIST AIRMASS INTO SE
TX WHICH MAKES SENSE BASED OFF 00Z LCH WIND PROFILE. THE NAM SEEMS
TO BE A BIT MORE AGGRESSIVE WITH BRINGING THE MOISTURE INTO THE
AREA WHERE GFS IS SLOWER. GFS IS ALSO FASTER IN BRINGING SOME
DRIER AIR INTO THE AREA FROM THE EAST. THIS MAY IMPACT
THUNDERSTORM CHANCES MID WEEK ESPECIALLY OVER NORTHERN PORTIONS OF
SE TX. FOR NOW RADAR SHOWS ACTIVITY ORGANIZING IN THE GULF AND
THIS WILL LIKELY BE THE BEGINNING OF THUNDERSTORM ACTIVITY ALONG
THE COAST. THINK 40/50 POPS LOOK ON TRACK FOR MUCH OF THE AREA FOR
THE REST OF THE WEEK. ON A CURIOUS NOTE...MESO MODELS SUCH AS WRF
ARW AND HRRR ARE NOT VERY ROBUST WITH CONVECTION FORMING UNTIL
MUCH LATER IN THE AFTERNOON. THIS BRINGS IN SOME DOUBT AS TO HOW
CONVECTION WILL EVOLVE TODAY.
UPPER LEVEL PATTERN WILL BE QUITE CONDUCIVE FOR CONVECTION. WATER
VAPOR IMAGERY SHOWS SHORTWAVE MOVING INTO SE TX FROM THE N GULF
TODAY AND FORECAST MODELS CONTINUE TO STALL THIS FEATURE ALONG THE
COAST OR JUST INLAND OF MIDDLE TX COAST ON WEDNESDAY. THIS MEANS
AN OVERALL WEAKNESS IN THE RIDGE WILL EXIST AND ONLY STRENGTHENED
BY BROAD TROUGH NOW OVER THE GREAT BASIN MOVING INTO THE PLAINS
FOR FRIDAY INTO SATURDAY. THE CUTOFF SHORTWAVE OR TUTT LOW WILL
THEN LIFT NORTH AS THE UPPER TROUGH STARTS TO MOVE THROUGH THE
PLAINS LATE FRI INTO SAT. AFTER THE TROUGH LIFTS OVERALL UPPER
LEVEL RIDGING OCCURS BUT THE RIDGE SEEMS TO BE STRETCHED OUT ALL
ALONG THE SOUTHERN TIER OF STATES.
THE OTHER MAJOR INGREDIENT FOR THUNDERSTORM CHANCES IS MOISTURE.
GOES SOUNDER PRECIP WATER PRODUCT SHOWS DEEP MOISTURE AXIS OR
ATMOSPHERIC MOISTURE RIVER COMING FROM THE CARIBBEAN INTO THE N
GULF. THIS PLUME OF MOISTURE WILL VARY IN ITS OVERALL MOISTURE
CONTENT FROM DAY TO DAY BUT IT WILL NOT TAKE MUCH TIME FOR
CONVECTION TO DEVELOP. MODEL SOUNDINGS SUPPORT CONVECTIVE TEMPS IN
THE UPPER 80S TO LOW 90S WITH PRECIP WATER VALUES AROUND 2.2 TO
2.4 INCHES. THIS MOISTURE PLUME REMAINING IN PLACE FOR THE NEXT
DAY OR TWO SHOULD SUPPORT CONTINUED THUNDERSTORM ACTIVITY ACROSS
THE AREA. WITH BREAKS IN CLOUD COVER THESE CONVECTIVE TEMPS LOOK
TO BE ACHIEVABLE EVEN IN THE LATE MORNING HOURS. IT LOOKS LIKE
TODAY INTO WEDNESDAY WILL CARRY THE HIGHEST CHANCES BUT EVEN 30/40
POPS LOOK REASONABLE FOR THE END OF THE WEEK.
CONVECTION AND CLOUD COVER SHOULD KNOCK TEMPS DOWN A COUPLE OF
DEGREES FROM THE LAST FEW DAYS. HIGH TEMPS WILL REACH LOW 90S
ALONG THE COAST AND POSSIBLY INLAND. MIN TEMPS MAY BE ABOVE
NORMAL WITH HIGHER MOISTURE ALONG THE COAST. LOW TEMPS WILL MAINLY
BE DRIVEN BY ANY OUTFLOW BOUNDARIES THAT MOVE THROUGH THE AREA.
MAIN IMPACTS FROM THIS CHANGE IN THE WEATHER PATTERN WILL BE
POSSIBILITY OF HEAVY RAINFALL ON ANY OF THE NEXT FEW DAYS. HIGHEST
RAINFALL TOTALS WILL LIKELY BE ALONG THE COAST AND OFFSHORE.
THAT`S NOT TO SAY A FEW STRONG STORMS COULD NOT FORM INLAND WHICH
COULD PRODUCE HEAVY RAINFALL. HOURLY RAIN RATES OF 1-2 INCHES AN
HOUR WOULD NOT BE OUT OF THE QUESTION SO ISO 1-3 INCH AMOUNTS
WOULD BE POSSIBLE. LOOKING AT GRIDDED FFG AND NASA SPORT LIS
DATA...IF ANYTHING MOST FLOOD PRONE AREAS WILL BE EAST OF
INTERSTATE 45 INTO E TX. AT THIS TIME ANY FLOODING PROBLEMS WILL
BE VERY LOCALIZED. OF COURSE URBAN AREAS WITH POOR DRAINAGE WILL
ALWAYS BE AN ISSUE ONCE RAIN RATES APPROACH 2 INCHES AN HOUR. THE
HARDEST PART OF THE FORECAST IS TRYING THE NARROW DOWN ANY ONE DAY
THAT WILL HAVE A HIGHER POTENTIAL FOR HEAVY RAINFALL. AT THIS TIME
THE NEXT 4 DAYS HAVE THAT POTENTIAL.
39
&&
.MARINE...
AN UPPER LEVEL DISTURBANCE WILL BRING SHOWERS AND THUNDERSTORMS
TO THE WATERS TODAY AND WEDNESDAY. FAIRLY LIGHT EAST TO SOUTHEAST
FLOW WILL BECOME MORE MODERATE...MAINLY IN THE 10 TO 15 KNOT
RANGE...LATER THIS AFTERNOON...AND CONTINUING THROUGH LATE IN THE
WEEK. THERE WILL BE AN INCREASE IN SEAS CORRESPONDING...INTO THE 2
TO 4 FEET RANGE FOR COASTAL WATERS.
46
&&
.PRELIMINARY POINT TEMPS/POPS...
COLLEGE STATION (CLL) 96 76 96 75 93 / 20 20 20 20 30
HOUSTON (IAH) 92 77 93 76 92 / 50 20 40 20 50
GALVESTON (GLS) 90 80 88 80 89 / 50 40 50 50 50
&&
.HGX WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
GM...NONE.
&&
$$
DISCUSSION...39
AVIATION/MARINE...46
AREA FORECAST DISCUSSION...UPDATED
NWS FORT WORTH TX
1124 PM CDT MON AUG 25 2014
.AVIATION...
/6Z TAFS/
VFR CONDITIONS EXPECTED THROUGH THE PERIOD ALTHOUGH SOME HIGH
CLOUD IS SPREADING INTO THE AREA FROM CONVECTION TO THE EAST. THIS
SHOULD THIN OUT OVERNIGHT. GENERALLY LIGHT EAST-SOUTHEAST WINDS
WILL PREVAIL THROUGH TUESDAY. THERE IS SOME INCREASING MOISTURE
ACROSS EAST TEXAS WHICH WILL MOVE INTO NORTH TEXAS TOMORROW AND
WILL LIKELY SET OFF A FEW SHOWERS AND THUNDERSTORMS. RIGHT NOW
THINK THE MOST LIKELY AREAS WILL BE EAST AND SOUTH OF THE MAJOR
METROPLEX AIRPORTS. WILL CONTINUE WITH A VCTS AT WACO TOMORROW
AFTERNOON. OTHERWISE...NO SIGNIFICANT AVIATION CONCERNS OUTSIDE OF
ISOLATED AFTERNOON CONVECTION.
DUNN
&&
.UPDATE...
IT IS ANOTHER QUIET NIGHT ACROSS NORTH AND CENTRAL TEXAS.
ALTHOUGH THE ISOLATED SHOWERS AND THUNDERSTORMS OVER SOUTHEAST
TEXAS...SOUTHEAST OF A CENTER TO LUFKIN LINE...ARE MOVING
NORTHWEST...THEY WILL NOT MAKE IT INTO FORECAST AREA TONIGHT. WE
WILL SEE CLEAR TO PARTLY CLOUDY SKIES WITH LOWS IN THE 70S AREA
WIDE. WITH INCREASED MOISTURE TOMORROW...TEMPERATURES SHOULD BE
AT TO A FEW DEGREES LOWER THAN TODAY. NO CHANGES TO THE FORECAST
ARE PLANNED AT THIS TIME.
58
&&
.PREV DISCUSSION... /ISSUED 333 PM CDT MON AUG 25 2014/
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
&&
.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.
&&
$$
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
1138 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 06Z TAFS THROUGH 06Z TUESDAY NIGHT)
ISSUED AT 1138 PM CDT MON AUG 25 2014
WHILE SOME ISOLATED TO SCATTERED SHOWERS AND THUNDERSTORMS HAVE
DEVELOPED ACROSS THE REGION...RST AND LSE ARE EXPECTED TO STAY
MAINLY DRY AS THIS WAVE MOVES THROUGH. WINDS WILL REMAIN OUT OF
THE WEST AS A COLD FRONT DRIFTS THROUGH THE REGION AND HIGH
PRESSURE PUSHES IN FROM THE NORTHWEST. SOME RAIN AND STORMS MAY
MOVE IN LATE TUESDAY NIGHT...BUT IT MAINLY LOOKS LIKE IT WOULD BE
AFTER 6Z AND NOT INCLUDED ON THESE TAFS.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...04
LONG TERM...04
AVIATION...HALBACH
AREA FORECAST DISCUSSION...UPDATED
NWS CHICAGO/ROMEOVILLE IL
1051 AM CDT TUE AUG 26 2014
.MESOSCALE DISCUSSION...
1051 AM CDT...
SCATTERED STRONG TO ISOLATED SEVERE STORMS CONTINUE TO DEVELOP
SOUTHEASTWARD ACROSS THE AREA. A WELL-DEFINED SHELF CLOUD WITH WINDS
ABOVE 35 MPH...POSSIBLY NEAR 50 MPH BASED ON TERMINAL DOPPLER
WEATHER RADAR DATA...IS MOVING SOUTHEASTWARD INTO THE CHICAGO METRO
AREA. UPDRAFTS CONTINUE TO DEVELOP ALONG THIS...WITH CORRELATING
DOWNDRAFTS OF STORMS BEING THE MOST CONCERNING FOR PUSHING WINDS TO
THE HIGHER MAGNITUDES.
MTF
PREV DISCUSSION...
328 AM CDT
SHOWER AND THUNDERSTORM CHANCES AND TIMING WILL BE THE MAIN FORECAST
CHALLENGE THROUGH THE PERIOD FOLLOWED BY TEMPS AS THEY MAY BE
INFLUENCED BY ROUNDS OF CONVECTION. WATER VAPOR IMAGERY SHOWS THE
UPPER WHICH CONTRIBUTED TO THE BREAKING DOWN OF THE PERSISTENT UPPER
RIDGE OVER THE AREA IS TRACKING NORTHEAST ACROSS JAMES BAY LEAVING
CORRIDOR OF FAIRLY ZONAL FLOW ACROSS THE UPPER MIDWEST AND GREAT
LAKES. ANOTHER UPPER LOW IS SLOWLY SPINNING SOUTHWARD ACROSS
NORTHERN CALIFORNIA AND NEVADA CUTTING OFF FROM A TROUGH AXIS TO THE
NORTH WHICH IS MOVING EAST ACROSS THE CANADIAN PRAIRIES. A RIDGE
AXIS IS PIVOTING EASTWARD OVER WESTERN CANADA AS AN UPPER TROUGH
MOVES EASTWARD ACROSS SOUTHERN ALASKA. AT THE SURFACE...LOW PRESSURE
IS OVER JAMES BAY WITH A COLD FRONT TRAILING IT ACROSS CENTRAL
WISCONSIN AND IOWA. ONE AREA OF HIGH PRESSURE IS STRETCHED UP AND
DOWN THE EASTERN SEABOARD WHILE ANOTHER HIGH IS OVER THE NORTHERN
PLAINS IN THE WAKE OF THE COLD FRONT.
TODAY...THE AFOREMENTIONED COLD FRONT TO THE NORTHWEST WILL BE
ENTERING THE CWA IN THE NEXT FEW HOURS BUT LOOKS TO GET HUNG UP NEAR
THE I-80 CORRIDOR FOR A TIME LATER THIS MORNING. CONVECTIVE TRENDS
ARE A CHALLENGE THIS MORNING WITH THE FRONT AND SEVERAL OTHER
FEATURES PRESENT TO KEEP SHOWERS AND THUNDERSTORMS GOING. EVENING
UPPER AIR ANALYSIS SHOWED AN UPPER JET CORE FROM SOUTHWEST MINNESOTA
TO JAMES BAY WHICH PLACES THE RIGHT ENTRANCE REGION OVER IOWA. THE
NOSE OF A LOW LEVEL JET IS AIMED INTO SOUTHEAST NEBRASKA BUT TURNS
WESTERLY ACROSS SOUTHERN IOWA. THIS HAS LED TO A DECENT DIFFERENTIAL
DIVERGENCE SET UP BETWEEN THE LOW LEVEL AND UPPER LEVEL JETS. IN
ADDITION...AN UPPER WAVE APPEARS TO BE TRACKING NORTHEAST ACROSS
NORTH CENTRAL KANSAS. ALL OF THIS IS LEADING TO VARYING DEGREES OF
CONVECTIVE DEVELOPMENT FROM EAST CENTRAL NEBRASKA/WEST CENTRAL
IOWA...WHERE THE COVERAGE IS EXTENSIVE...TO EASTERN IOWA AND NOW
JUST INTO NW ILLINOIS WHERE COVERAGE IS ISOLATED THUS FAR. 850-300
MB THICKNESS TAKES THIS ACTIVITY EASTWARD. HOW WELL THIS SUSTAINS
ITSELF IS IN QUESTION BUT GIVEN THAT THERE ARE SEVERAL LARGE SCALE
FACTORS DRIVING IT AND THERE IS A GOOD POOL OF INSTABILITY NEAR AND
AHEAD OF THE FRONT THERE IS GOOD REASON FOR IT TO CONTINUE. NOT TOO
MENTION THE TREND OF THE PAST SEVERAL DAYS HAS BEEN FOR MORNING
CONVECTION TO FESTER AND/OR SPIN OFF NEW CONVECTION MIDDAY ONWARD.
ISOLATED TO SCATTERED ACTIVITY WILL BEGIN TO AFFECT THE AREA IN THE
NEXT FEW HOURS WHILE THE MORE SOLID ACTIVITY OVER WEST CENTRAL IOWA
AND EAST CENTRAL NEBRASKA OR ACTIVITY SPUN OFF FROM IT WOULD
POTENTIALLY AFFECT THE AREA LATE MORNING/EARLY AFTERNOON. THIS
COMPLEX HAS BEEN ORGANIZING AND ACCELERATING EASTWARD TO SOME DEGREE
IN THE LAST HOUR OR SO. IN ADDITION...WITH THE FRONTAL BOUNDARY
LIKELY STILL IN THE SOUTHERN CWA THIS AFTERNOON IT MAY SERVE AS
FOCUS FOR NEW CONVECTION AS WELL. IT DOES APPEAR THAT POPS WILL
TAPER OFF ACROSS THE NORTH DURING THE LATE AFTERNOON. TORRENTIAL
DOWNPOURS AND LOCALIZED FLOODING WILL BE THE MAIN THREAT WITH ANY
STORMS ONCE AGAIN...WITH GUSTY STRAIGHT LINE WINDS AND ADDITIONAL
THREAT. MID LEVEL AIR WILL STILL BE QUITE WARM WITH H85 TEMPS NEAR
+20C BUT LOW LEVEL WINDS WILL TURN NORTHERLY AND EVEN NORTHEASTERLY
NEAR LAKE MICHIGAN. EXPECT HIGHS IN THE UPPER 80S FAR SOUTH AND NEAR
80 NEAR THE LAKE AND FAR NORTHERN INLAND AREAS...WITH LOW TO MID 80S
IN BETWEEN. CONVECTION COULD ONCE AGAIN HAVE AN IMPACT ON
HIGHS...ESPECIALLY SOUTH IF ACTIVITY CONTINUES INTO THE AFTERNOON
GIVEN THE BETTER PROXIMITY TO THE FRONTAL BOUNDARY.
TONIGHT THROUGH FRIDAY...CONVECTIVE CHANCES REMAIN A CHALLENGE THIS
PERIOD. THE SURFACE FRONT WILL BE TO THE SOUTH OF THE AREA BUT THE
MAIN MID LEVEL THERMAL GRADIENT WILL BE OVERHEAD AND EVEN NORTH OF
THE AREA. THE LOW AMPLITUDE UPPER TROUGH CURRENTLY WORKING INTO THE
CANADIAN PRAIRIES IN THE MAIN NORTHERN STREAM OF FLOW WILL BE
PASSING TO THE NORTH SUPPLYING MODEST HEIGHT FALLS TO THE LOCAL AREA
TONIGHT AND WEDNESDAY MORNING. THE RIGHT ENTRANCE OF THE UPPER JET
WILL ALSO BE PASSING OVER THE AREA. GUIDANCE SUGGESTS THAT THERE
WILL BE A WAVE EJECTING FROM THE CUTOFF UPPER TROUGH ACROSS THE
CENTRAL PLAINS AS WELL. IT APPEARS THAT CONVECTION WILL BE
DEVELOPING TO THE WEST TONIGHT THEN TRACK EASTWARD IN CONJUNCTION
WITH THE SYNOPTIC FEATURES. THIS SHOULD RESULT IN BEST CHANCES FOR
PRECIP LATER TONIGHT AND WEDNESDAY MORNING....THOUGH HAVE AN INKLING
THIS MAY BE A BIT FAST. THIS MAY BE ANOTHER SITUATION WHERE ACTIVITY
WILL BE DECAYING IN THE MORNING AS IS GETS CLOSER TO THE AREA. MUCH
OF THE AREA COULD SEE PRECIP BUT THE BEST FOCUS MAY BE ACROSS THE
SOUTH IN CLOSER PROXIMITY TO THE FRONT. THE CUTOFF UPPER LOW WILL BE
SLOWLY BUT STEADILY MOVING EASTWARD FORCING MODEST RIDGING INTO THE
AREA GOING INTO THURSDAY. THIS WILL BRING ANOTHER PUSH OF WARM
ADVECTION ACROSS THE CENTRAL U.S. WEDNESDAY NIGHT AND DRIVE THE
FRONTAL BOUNDARY NORTH AS A WARM FRONT. AT THIS POINT THE BULK OF
THE CONVECTION LOOKS TO BE TO THE WEST WEDNESDAY NIGHT WITH IT THEN
AFFECTING THE CWA THURSDAY...WITH BEST CHANCES NORTH AS THE WARM
FRONT LIFTS NORTH. THE AREA WILL BE ON THE PERIPHERY OF THE RIDGE
ONCE AGAIN FAVORING MORE CONVECTION...ESPECIALLY NORTH...THROUGH
FRIDAY. HEAVY RAINFALL AND GUSTY WINDS WILL BE THE MAIN THREATS WITH
THE STORMS THROUGH THE END OF THE WEEK. TEMPERATURES WILL RANGE FROM
THE LOWER 70S NEAR THE LAKE WEDNESDAY WITH A STEADY NORTHEAST
WIND...WITH UPPER 70S INLAND NORTH TO LOWER 80S SOUTH. EASTERLY
WINDS WILL KEEP SIMILAR TEMPS IN PLACE THURSDAY WITH WARMER READINGS
FRIDAY ALL THE WAY TO THE LAKE WITH THE FRONT MOVING NORTHWARD.
TEMPS MAY BE AFFECTED BY CONVECTION EACH DAY.
SATURDAY AND BEYOND...ACTIVE WEATHER CONTINUES THROUGH EARLY NEXT
WEEK AS THE CUTOFF TROUGH MOVES ACROSS THE AREA OVER THE WEEKEND
BRINGING CONTINUED SHOWER AND THUNDERSTORM ACTIVITY. ANOTHER UPPER
LOW IS FORECAST TO TRACK ACROSS SOUTHERN CANADA MONDAY/TUESDAY
BRINGING A COLD FRONT ACROSS THE AREA ALONG WITH MORE STORM CHANCES.
HIGHS SHOULD CONTINUE IN THE UPPER 70S AND LOWER 80S.
MDB
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 14Z...
* SCT VCTS THROUGH 17Z. STRONGER STORMS MAY PRODUCE GUSTY WINDS IN
EXCESS OF 30 KT AND MVFR OR LOWER VSBYS.
* WIND SHIFT TO N WINDS ARND 8 KT ARND 16Z.
* LAKE BREEZE SHIFTING WINDS TO NE LESS THAN 10 KT ARND 20Z.
* CHANCE OF TSRA WED MORNING.
JEE
//DISCUSSION...UPDATED 12Z...
SCATTERED TSRA HAS DEVELOPED MAINLY EAST OF THE TERMINALS BUT
STILL SOME ACTIVITY ACROSS NORTHERN IL. CONFIDENCE REGARDING
DIRECT IMPACTS AT THE TERMINALS OVER THE NEXT FEW HOURS IS LOW
BUT WILL CONTINUE WITH TEMPO MENTION THRU 14Z...WHEN THIS ACTIVITY
SHOULD BE EAST AND SOUTHEAST OF THE TERMINALS. FOCUS THEN SHIFTS
TO LINE OF TSRA MOVING ACROSS EASTERN IOWA. MOST SHORT TERM/HI RES
GUIDANCE SHOWS THIS COMPLEX WEAKENING AS IT MOVES ACROSS NORTHWEST
IL LATER THIS MORNING. CONFIDENCE FOR TSRA REACHING RFD IS HIGH
ENOUGH TO INCLUDE MENTION THERE BUT FURTHER EAST HAVE OPTED FOR
SHRA AT DPA AND THEN DRY ORD/MDW/GYY. TRENDS WILL NEED TO BE
MONITORED IN THE NEXT FEW HOURS. IF THIS ACTIVITY HOLDS
TOGETHER...IT COULD ARRIVE INTO THE ORD/MDW AREA AROUND 17Z.
A WEAK COLD FRONT WILL MOVE SOUTH ACROSS THE TERMINALS THIS
MORNING...PERHAPS AIDED BY OUTFLOW FROM THUNDERSTORMS OVER EASTERN
IOWA. WINDS WILL SHIFT NORTHERLY BEHIND THE FRONT WITH PREVAILING
SPEEDS LIKELY UNDER 10KTS. WINDS REMAIN NORTH/NORTHEAST UNDER
10KTS THRU EARLY/MID AFTERNOON WHEN A LAKE BREEZE MAY MOVE ACROSS
THE CHICAGO AREA TERMINALS...TURNING WINDS MORE NORTHEASTERLY WITH
SPEEDS PERHAPS AROUND 10KTS...THOUGH CONFIDENCE ON SPEEDS IS LOW.
WIND DIRECTION WILL THEN REMAIN NORTHEAST FOR THE REMAINDER OF THE
PERIOD WITH SPEEDS UNDER 10KTS.
ANOTHER ROUND OF SHRA/TSRA IS POSSIBLE WEDNESDAY MORNING. TIMING
IS UNCERTAIN BUT CONFIDENCE OF TSRA NEARBY IS HIGH ENOUGH TO
INCLUDE PROB MENTION AND FOR NOW HAVE GONE WITH TIMING NEAR OR
JUST AFTER DAYBREAK. CMS
//ORD AND MDW CONFIDENCE...UPDATED 14Z...
* MEDIUM CONFIDENCE IN TSRA COVERAGE...MEDIUM-LOW CONFIDENCE IN A
TSRA MOVING OVER THE TERMINALS.
* MEDIUM-HIGH CONFIDENCE IN LAKE BREEZE WIND SPEEDS LESS THAN 10
KT...MEDIUM CONFIDENCE IN LAKE BREEZE TIMING.
* MEDIUM CONFIDENCE IN TSRA WED MORNING.
JEE
//OUTLOOK FOR ORD/MDW FOR 00Z THURSDAY-12Z TUESDAY...UPDATED 12Z...
* WEDNESDAY NIGHT...SLIGHT CHANCE OF TSRA.
* THURSDAY THROUGH MONDAY...CHANCE OF TSRA.
&&
.MARINE...
246 AM...LOW PRESSURE NEAR JAMES BAY WILL CONTINUE EAST ACROSS
NORTHERN QUEBEC TODAY AS A TRAILING COLD FRONT MOVES SOUTH ACROSS
LAKE MICHIGAN THIS MORNING. WEST/SOUTHWEST WINDS WILL SHIFT TO THE
NORTH BUT SPEEDS SHOULD REMAIN IN THE 10-15KT RANGE. HIGH PRESSURE
OVER THE DAKOTAS WILL MOVE EAST ACROSS THE LAKES REGION WEDNESDAY
INTO WEDNESDAY NIGHT. AS IT DOES...THE GRADIENT WILL TIGHTEN SOME
ON THE FAR SOUTH END OF THE LAKE...ALLOWING NORTH TO NORTHEAST
WINDS TO INCREASE INTO THE 10-20KT RANGE. THIS HIGH WILL MOVE EAST
THURSDAY WITH A WARM FRONT LIFTING BACK NORTH ACROSS THE LAKE
THURSDAY NIGHT...SHIFTING WINDS BACK SOUTHERLY. CMS
&&
.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
[top]
Area Forecast Discussion
NATIONAL WEATHER SERVICE LINCOLN IL
1046 AM CDT Tue Aug 26 2014
.UPDATE...
ISSUED AT 1038 AM CDT TUE AUG 26 2014
Front still to the northwest this morning and a series of
thunderstorms across the northern tier of the state. So far, only
a few showers have been triggered into ILX. Potential for showers
and thunderstorms still in place for Central Illinois through
today, as heat and high dwpts increase the instability ahead of
the front. Some minor updates to the hourly temperatures...but no
major updates at this time. Will likely be adjusting the forecast
into the afternoon as the front approaches...but at this point,
the updates will be minor.
&&
.SHORT TERM...(Today and tonight)
ISSUED AT 312 AM CDT TUE AUG 26 2014
One more hot and humid day is on tap for at least the southern half
of the KILX CWA, as heat index readings climb into the 105 to 110F
range during peak heating. The heat warning will continue from
Lincoln and south, with the heat advisory east to Champaign/Danville
through early evening.
Last evening some cooler air was pushed out from a line of storms
that clipped our north from Stark County to Champaign/Vermilion
counties and south along the Indiana border. That worked to lower
dew points across the north, which should help to keep the heat
indices a bit lower during the afternoon, but still hot in the
upper 90s.
Once again the high-res models are having a hard time with current
convection and are all over the board with respect to storm
development over the next 24 hours. When merged with the lower
resolution models, the general theme is for a line of storms to
eventually develop across our northern counties as a cold front
slowly moves south into our forecast area. A few storm cells
developing in eastern Iowa over the last hour has increased some
confidence that a few storms could affect our northwestern counties
by mid-morning, so will keep at least chance PoPs NW of Peoria this
morning. The daytime storms are projected to drift south as they
dissipate toward I-72 later this afternoon. The next complex of
storms is projected for later tonight, when a stronger MCS is
forecast to roll out of Iowa. Under that scenario, storms would
affect areas north of Peoria after 08z/2am CDT, where we have likely
PoPs.
There remains a high level of elevated instability, with plenty of
precipitable water, so any storms that can overcome the mid-level
warming could produce some very heavy rainfall and strong winds over
the next 24 hours.
&&
.LONG TERM...(Wednesday through Labor Day)
ISSUED AT 312 AM CDT TUE AUG 26 2014
Upper ridge will be breaking down on Wednesday as a wave moves
through the upper Great Lakes region. Still watching the deep trough
seen on water vapor imagery across the western U.S. this morning.
Last couple model runs had some reasonable agreement with tracking
this feature into the Plains by early Saturday, but have some
disagreements resolving the split flow over the central U.S. as a
trough digs over the Pacific Northwest. The ECMWF largely dampen out
the Plains wave, while the GFS keeps it somewhat intact and lifts it
into Wisconsin on Sunday, possibly due to some feedback issues. Have
leaned the holiday weekend forecast more toward the ECMWF as a
result.
In the nearer term, the 00Z models largely bring the front through
most of the forecast area by Wednesday evening, with the NAM
furthest north and the GEM/GFS furthest south. Best shower/storm
threat will be during the morning before the precipitation is
shunted into what`s left of the ridge. After that, focus shifts to
our northwest as the front lifts back northward in response to the
wave moving onto the Plains. Frequent MCS activity will lead to
potential flooding concerns across Iowa/Wisconsin, with mainly
scattered activity in our area from the remnants of said activity or
other development along the boundary.
Rather humid conditions expected to continue on Wednesday, until
drier air spreads in from a high pressure building into the Great
Lakes. However, the humidity will return on Thursday as the front
lifts back north. Temperatures across the southeast CWA may still
reach the lower 90s Wednesday and Thursday, but highs in the 80s
will prevail through the period.
&&
.AVIATION...(For the 12Z TAFS through 12Z Wednesday morning)
ISSUED AT 655 AM CDT TUE AUG 26 2014
A cold front will progress into central IL this afternoon.
Scattered thunderstorms are expected near the front, especially
this afternoon. PIA and BMI could see a few showers and possibly
storms after 15z this morning. The high res models have varying
solutions, with the RAP showing a line of convection across
central IL already at 12z this morning, which is not occurring.
The HRRR holds off storms until 16z near PIA/BMI, with additional
storms behind the cold front this afternoon.
The lower resolution NAM/GFS/Canadian/ECMWF have varying
precipitation patterns over the next 24 hours as well. Overall,
will stick with afternoon storms near the cold front at all TAF
sites. There is some agreement that after midnight tonight,
an MCV will roll out of Iowa into NC Illinois, triggering the next
round of storms. Those would affect PIA and BMI mainly, based on
the expected storm track.
Winds will start out south-southwest ahead of the cold front. By
afternoon, northerly winds will develop behind the front
progressively from PIA to BMI to CMI. The frontal motion will slow
down by this evening as it stalls out over SPI/DEC. Winds at those
sites could just become variable for much of the night.
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
EXCESSIVE HEAT WARNING until 7 PM CDT this evening FOR ILZ042-
047>054-056-061>063-066>068-071>073.
HEAT ADVISORY until 7 PM CDT this evening FOR ILZ043>046-055-057.
&&
$$
UPDATE...HJS
SHORT TERM...SHIMON
LONG TERM...GEELHART
AVIATION...SHIMON
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
922 AM CDT TUE AUG 26 2014
.DISCUSSION...
328 AM CDT
SHOWER AND THUNDERSTORM CHANCES AND TIMING WILL BE THE MAIN FORECAST
CHALLENGE THROUGH THE PERIOD FOLLOWED BY TEMPS AS THEY MAY BE
INFLUENCED BY ROUNDS OF CONVECTION. WATER VAPOR IMAGERY SHOWS THE
UPPER WHICH CONTRIBUTED TO THE BREAKING DOWN OF THE PERSISTENT UPPER
RIDGE OVER THE AREA IS TRACKING NORTHEAST ACROSS JAMES BAY LEAVING
CORRIDOR OF FAIRLY ZONAL FLOW ACROSS THE UPPER MIDWEST AND GREAT
LAKES. ANOTHER UPPER LOW IS SLOWLY SPINNING SOUTHWARD ACROSS
NORTHERN CALIFORNIA AND NEVADA CUTTING OFF FROM A TROUGH AXIS TO THE
NORTH WHICH IS MOVING EAST ACROSS THE CANADIAN PRAIRIES. A RIDGE
AXIS IS PIVOTING EASTWARD OVER WESTERN CANADA AS AN UPPER TROUGH
MOVES EASTWARD ACROSS SOUTHERN ALASKA. AT THE SURFACE...LOW PRESSURE
IS OVER JAMES BAY WITH A COLD FRONT TRAILING IT ACROSS CENTRAL
WISCONSIN AND IOWA. ONE AREA OF HIGH PRESSURE IS STRETCHED UP AND
DOWN THE EASTERN SEABOARD WHILE ANOTHER HIGH IS OVER THE NORTHERN
PLAINS IN THE WAKE OF THE COLD FRONT.
TODAY...THE AFOREMENTIONED COLD FRONT TO THE NORTHWEST WILL BE
ENTERING THE CWA IN THE NEXT FEW HOURS BUT LOOKS TO GET HUNG UP NEAR
THE I-80 CORRIDOR FOR A TIME LATER THIS MORNING. CONVECTIVE TRENDS
ARE A CHALLENGE THIS MORNING WITH THE FRONT AND SEVERAL OTHER
FEATURES PRESENT TO KEEP SHOWERS AND THUNDERSTORMS GOING. EVENING
UPPER AIR ANALYSIS SHOWED AN UPPER JET CORE FROM SOUTHWEST MINNESOTA
TO JAMES BAY WHICH PLACES THE RIGHT ENTRANCE REGION OVER IOWA. THE
NOSE OF A LOW LEVEL JET IS AIMED INTO SOUTHEAST NEBRASKA BUT TURNS
WESTERLY ACROSS SOUTHERN IOWA. THIS HAS LED TO A DECENT DIFFERENTIAL
DIVERGENCE SET UP BETWEEN THE LOW LEVEL AND UPPER LEVEL JETS. IN
ADDITION...AN UPPER WAVE APPEARS TO BE TRACKING NORTHEAST ACROSS
NORTH CENTRAL KANSAS. ALL OF THIS IS LEADING TO VARYING DEGREES OF
CONVECTIVE DEVELOPMENT FROM EAST CENTRAL NEBRASKA/WEST CENTRAL
IOWA...WHERE THE COVERAGE IS EXTENSIVE...TO EASTERN IOWA AND NOW
JUST INTO NW ILLINOIS WHERE COVERAGE IS ISOLATED THUS FAR. 850-300
MB THICKNESS TAKES THIS ACTIVITY EASTWARD. HOW WELL THIS SUSTAINS
ITSELF IS IN QUESTION BUT GIVEN THAT THERE ARE SEVERAL LARGE SCALE
FACTORS DRIVING IT AND THERE IS A GOOD POOL OF INSTABILITY NEAR AND
AHEAD OF THE FRONT THERE IS GOOD REASON FOR IT TO CONTINUE. NOT TOO
MENTION THE TREND OF THE PAST SEVERAL DAYS HAS BEEN FOR MORNING
CONVECTION TO FESTER AND/OR SPIN OFF NEW CONVECTION MIDDAY ONWARD.
ISOLATED TO SCATTERED ACTIVITY WILL BEGIN TO AFFECT THE AREA IN THE
NEXT FEW HOURS WHILE THE MORE SOLID ACTIVITY OVER WEST CENTRAL IOWA
AND EAST CENTRAL NEBRASKA OR ACTIVITY SPUN OFF FROM IT WOULD
POTENTIALLY AFFECT THE AREA LATE MORNING/EARLY AFTERNOON. THIS
COMPLEX HAS BEEN ORGANIZING AND ACCELERATING EASTWARD TO SOME DEGREE
IN THE LAST HOUR OR SO. IN ADDITION...WITH THE FRONTAL BOUNDARY
LIKELY STILL IN THE SOUTHERN CWA THIS AFTERNOON IT MAY SERVE AS
FOCUS FOR NEW CONVECTION AS WELL. IT DOES APPEAR THAT POPS WILL
TAPER OFF ACROSS THE NORTH DURING THE LATE AFTERNOON. TORRENTIAL
DOWNPOURS AND LOCALIZED FLOODING WILL BE THE MAIN THREAT WITH ANY
STORMS ONCE AGAIN...WITH GUSTY STRAIGHT LINE WINDS AND ADDITIONAL
THREAT. MID LEVEL AIR WILL STILL BE QUITE WARM WITH H85 TEMPS NEAR
+20C BUT LOW LEVEL WINDS WILL TURN NORTHERLY AND EVEN NORTHEASTERLY
NEAR LAKE MICHIGAN. EXPECT HIGHS IN THE UPPER 80S FAR SOUTH AND NEAR
80 NEAR THE LAKE AND FAR NORTHERN INLAND AREAS...WITH LOW TO MID 80S
IN BETWEEN. CONVECTION COULD ONCE AGAIN HAVE AN IMPACT ON
HIGHS...ESPECIALLY SOUTH IF ACTIVITY CONTINUES INTO THE AFTERNOON
GIVEN THE BETTER PROXIMITY TO THE FRONTAL BOUNDARY.
TONIGHT THROUGH FRIDAY...CONVECTIVE CHANCES REMAIN A CHALLENGE THIS
PERIOD. THE SURFACE FRONT WILL BE TO THE SOUTH OF THE AREA BUT THE
MAIN MID LEVEL THERMAL GRADIENT WILL BE OVERHEAD AND EVEN NORTH OF
THE AREA. THE LOW AMPLITUDE UPPER TROUGH CURRENTLY WORKING INTO THE
CANADIAN PRAIRIES IN THE MAIN NORTHERN STREAM OF FLOW WILL BE
PASSING TO THE NORTH SUPPLYING MODEST HEIGHT FALLS TO THE LOCAL AREA
TONIGHT AND WEDNESDAY MORNING. THE RIGHT ENTRANCE OF THE UPPER JET
WILL ALSO BE PASSING OVER THE AREA. GUIDANCE SUGGESTS THAT THERE
WILL BE A WAVE EJECTING FROM THE CUTOFF UPPER TROUGH ACROSS THE
CENTRAL PLAINS AS WELL. IT APPEARS THAT CONVECTION WILL BE
DEVELOPING TO THE WEST TONIGHT THEN TRACK EASTWARD IN CONJUNCTION
WITH THE SYNOPTIC FEATURES. THIS SHOULD RESULT IN BEST CHANCES FOR
PRECIP LATER TONIGHT AND WEDNESDAY MORNING....THOUGH HAVE AN INKLING
THIS MAY BE A BIT FAST. THIS MAY BE ANOTHER SITUATION WHERE ACTIVITY
WILL BE DECAYING IN THE MORNING AS IS GETS CLOSER TO THE AREA. MUCH
OF THE AREA COULD SEE PRECIP BUT THE BEST FOCUS MAY BE ACROSS THE
SOUTH IN CLOSER PROXIMITY TO THE FRONT. THE CUTOFF UPPER LOW WILL BE
SLOWLY BUT STEADILY MOVING EASTWARD FORCING MODEST RIDGING INTO THE
AREA GOING INTO THURSDAY. THIS WILL BRING ANOTHER PUSH OF WARM
ADVECTION ACROSS THE CENTRAL U.S. WEDNESDAY NIGHT AND DRIVE THE
FRONTAL BOUNDARY NORTH AS A WARM FRONT. AT THIS POINT THE BULK OF
THE CONVECTION LOOKS TO BE TO THE WEST WEDNESDAY NIGHT WITH IT THEN
AFFECTING THE CWA THURSDAY...WITH BEST CHANCES NORTH AS THE WARM
FRONT LIFTS NORTH. THE AREA WILL BE ON THE PERIPHERY OF THE RIDGE
ONCE AGAIN FAVORING MORE CONVECTION...ESPECIALLY NORTH...THROUGH
FRIDAY. HEAVY RAINFALL AND GUSTY WINDS WILL BE THE MAIN THREATS WITH
THE STORMS THROUGH THE END OF THE WEEK. TEMPERATURES WILL RANGE FROM
THE LOWER 70S NEAR THE LAKE WEDNESDAY WITH A STEADY NORTHEAST
WIND...WITH UPPER 70S INLAND NORTH TO LOWER 80S SOUTH. EASTERLY
WINDS WILL KEEP SIMILAR TEMPS IN PLACE THURSDAY WITH WARMER READINGS
FRIDAY ALL THE WAY TO THE LAKE WITH THE FRONT MOVING NORTHWARD.
TEMPS MAY BE AFFECTED BY CONVECTION EACH DAY.
SATURDAY AND BEYOND...ACTIVE WEATHER CONTINUES THROUGH EARLY NEXT
WEEK AS THE CUTOFF TROUGH MOVES ACROSS THE AREA OVER THE WEEKEND
BRINGING CONTINUED SHOWER AND THUNDERSTORM ACTIVITY. ANOTHER UPPER
LOW IS FORECAST TO TRACK ACROSS SOUTHERN CANADA MONDAY/TUESDAY
BRINGING A COLD FRONT ACROSS THE AREA ALONG WITH MORE STORM CHANCES.
HIGHS SHOULD CONTINUE IN THE UPPER 70S AND LOWER 80S.
MDB
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 14Z...
* SCT VCTS THROUGH 17Z. STRONGER STORMS MAY PRODUCE GUSTY WINDS IN
EXCESS OF 30 KT AND MVFR OR LOWER VSBYS.
* WIND SHIFT TO N WINDS ARND 8 KT ARND 16Z.
* LAKE BREEZE SHIFTING WINDS TO NE LESS THAN 10 KT ARND 20Z.
* CHANCE OF TSRA WED MORNING.
JEE
//DISCUSSION...UPDATED 12Z...
SCATTERED TSRA HAS DEVELOPED MAINLY EAST OF THE TERMINALS BUT
STILL SOME ACTIVITY ACROSS NORTHERN IL. CONFIDENCE REGARDING
DIRECT IMPACTS AT THE TERMINALS OVER THE NEXT FEW HOURS IS LOW
BUT WILL CONTINUE WITH TEMPO MENTION THRU 14Z...WHEN THIS ACTIVITY
SHOULD BE EAST AND SOUTHEAST OF THE TERMINALS. FOCUS THEN SHIFTS
TO LINE OF TSRA MOVING ACROSS EASTERN IOWA. MOST SHORT TERM/HI RES
GUIDANCE SHOWS THIS COMPLEX WEAKENING AS IT MOVES ACROSS NORTHWEST
IL LATER THIS MORNING. CONFIDENCE FOR TSRA REACHING RFD IS HIGH
ENOUGH TO INCLUDE MENTION THERE BUT FURTHER EAST HAVE OPTED FOR
SHRA AT DPA AND THEN DRY ORD/MDW/GYY. TRENDS WILL NEED TO BE
MONITORED IN THE NEXT FEW HOURS. IF THIS ACTIVITY HOLDS
TOGETHER...IT COULD ARRIVE INTO THE ORD/MDW AREA AROUND 17Z.
A WEAK COLD FRONT WILL MOVE SOUTH ACROSS THE TERMINALS THIS
MORNING...PERHAPS AIDED BY OUTFLOW FROM THUNDERSTORMS OVER EASTERN
IOWA. WINDS WILL SHIFT NORTHERLY BEHIND THE FRONT WITH PREVAILING
SPEEDS LIKELY UNDER 10KTS. WINDS REMAIN NORTH/NORTHEAST UNDER
10KTS THRU EARLY/MID AFTERNOON WHEN A LAKE BREEZE MAY MOVE ACROSS
THE CHICAGO AREA TERMINALS...TURNING WINDS MORE NORTHEASTERLY WITH
SPEEDS PERHAPS AROUND 10KTS...THOUGH CONFIDENCE ON SPEEDS IS LOW.
WIND DIRECTION WILL THEN REMAIN NORTHEAST FOR THE REMAINDER OF THE
PERIOD WITH SPEEDS UNDER 10KTS.
ANOTHER ROUND OF SHRA/TSRA IS POSSIBLE WEDNESDAY MORNING. TIMING
IS UNCERTAIN BUT CONFIDENCE OF TSRA NEARBY IS HIGH ENOUGH TO
INCLUDE PROB MENTION AND FOR NOW HAVE GONE WITH TIMING NEAR OR
JUST AFTER DAYBREAK. CMS
//ORD AND MDW CONFIDENCE...UPDATED 14Z...
* MEDIUM CONFIDENCE IN TSRA COVERAGE...MEDIUM-LOW CONFIDENCE IN A
TSRA MOVING OVER THE TERMINALS.
* MEDIUM-HIGH CONFIDENCE IN LAKE BREEZE WIND SPEEDS LESS THAN 10
KT...MEDIUM CONFIDENCE IN LAKE BREEZE TIMING.
* MEDIUM CONFIDENCE IN TSRA WED MORNING.
JEE
//OUTLOOK FOR ORD/MDW FOR 00Z THURSDAY-12Z TUESDAY...UPDATED 12Z...
* WEDNESDAY NIGHT...SLIGHT CHANCE OF TSRA.
* THURSDAY THROUGH MONDAY...CHANCE OF TSRA.
&&
.MARINE...
246 AM...LOW PRESSURE NEAR JAMES BAY WILL CONTINUE EAST ACROSS
NORTHERN QUEBEC TODAY AS A TRAILING COLD FRONT MOVES SOUTH ACROSS
LAKE MICHIGAN THIS MORNING. WEST/SOUTHWEST WINDS WILL SHIFT TO THE
NORTH BUT SPEEDS SHOULD REMAIN IN THE 10-15KT RANGE. HIGH PRESSURE
OVER THE DAKOTAS WILL MOVE EAST ACROSS THE LAKES REGION WEDNESDAY
INTO WEDNESDAY NIGHT. AS IT DOES...THE GRADIENT WILL TIGHTEN SOME
ON THE FAR SOUTH END OF THE LAKE...ALLOWING NORTH TO NORTHEAST
WINDS TO INCREASE INTO THE 10-20KT RANGE. THIS HIGH WILL MOVE EAST
THURSDAY WITH A WARM FRONT LIFTING BACK NORTH ACROSS THE LAKE
THURSDAY NIGHT...SHIFTING WINDS BACK SOUTHERLY. CMS
&&
.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
655 AM CDT Tue Aug 26 2014
.SHORT TERM...(Today and tonight)
ISSUED AT 312 AM CDT TUE AUG 26 2014
One more hot and humid day is on tap for at least the southern half
of the KILX CWA, as heat index readings climb into the 105 to 110F
range during peak heating. The heat warning will continue from
Lincoln and south, with the heat advisory east to Champaign/Danville
through early evening.
Last evening some cooler air was pushed out from a line of storms
that clipped our north from Stark County to Champaign/Vermilion
counties and south along the Indiana border. That worked to lower
dew points across the north, which should help to keep the heat
indices a bit lower during the afternoon, but still hot in the
upper 90s.
Once again the high-res models are having a hard time with current
convection and are all over the board with respect to storm
development over the next 24 hours. When merged with the lower
resolution models, the general theme is for a line of storms to
eventually develop across our northern counties as a cold front
slowly moves south into our forecast area. A few storm cells
developing in eastern Iowa over the last hour has increased some
confidence that a few storms could affect our northwestern counties
by mid-morning, so will keep at least chance PoPs NW of Peoria this
morning. The daytime storms are projected to drift south as they
dissipate toward I-72 later this afternoon. The next complex of
storms is projected for later tonight, when a stronger MCS is
forecast to roll out of Iowa. Under that scenario, storms would
affect areas north of Peoria after 08z/2am CDT, where we have likely
PoPs.
There remains a high level of elevated instability, with plenty of
precipitable water, so any storms that can overcome the mid-level
warming could produce some very heavy rainfall and strong winds over
the next 24 hours.
&&
.LONG TERM...(Wednesday through Labor Day)
ISSUED AT 312 AM CDT TUE AUG 26 2014
Upper ridge will be breaking down on Wednesday as a wave moves
through the upper Great Lakes region. Still watching the deep trough
seen on water vapor imagery across the western U.S. this morning.
Last couple model runs had some reasonable agreement with tracking
this feature into the Plains by early Saturday, but have some
disagreements resolving the split flow over the central U.S. as a
trough digs over the Pacific Northwest. The ECMWF largely dampen out
the Plains wave, while the GFS keeps it somewhat intact and lifts it
into Wisconsin on Sunday, possibly due to some feedback issues. Have
leaned the holiday weekend forecast more toward the ECMWF as a
result.
In the nearer term, the 00Z models largely bring the front through
most of the forecast area by Wednesday evening, with the NAM
furthest north and the GEM/GFS furthest south. Best shower/storm
threat will be during the morning before the precipitation is
shunted into what`s left of the ridge. After that, focus shifts to
our northwest as the front lifts back northward in response to the
wave moving onto the Plains. Frequent MCS activity will lead to
potential flooding concerns across Iowa/Wisconsin, with mainly
scattered activity in our area from the remnants of said activity or
other development along the boundary.
Rather humid conditions expected to continue on Wednesday, until
drier air spreads in from a high pressure building into the Great
Lakes. However, the humidity will return on Thursday as the front
lifts back north. Temperatures across the southeast CWA may still
reach the lower 90s Wednesday and Thursday, but highs in the 80s
will prevail through the period.
&&
.AVIATION...(For the 12Z TAFS through 12Z Wednesday morning)
ISSUED AT 655 AM CDT TUE AUG 26 2014
A cold front will progress into central IL this afternoon.
Scattered thunderstorms are expected near the front, especially
this afternoon. PIA and BMI could see a few showers and possibly
storms after 15z this morning. The high res models have varying
solutions, with the RAP showing a line of convection across
central IL already at 12z this morning, which is not occurring.
The HRRR holds off storms until 16z near PIA/BMI, with additional
storms behind the cold front this afternoon.
The lower resolution NAM/GFS/Canadian/ECMWF have varying
precipitation patterns over the next 24 hours as well. Overall,
will stick with afternoon storms near the cold front at all TAF
sites. There is some agreement that after midnight tonight,
an MCV will roll out of Iowa into NC Illinois, triggering the next
round of storms. Those would affect PIA and BMI mainly, based on
the expected storm track.
Winds will start out south-southwest ahead of the cold front. By
afternoon, northerly winds will develop behind the front
progressively from PIA to BMI to CMI. The frontal motion will slow
down by this evening as it stalls out over SPI/DEC. Winds at those
sites could just become variable for much of the night.
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
EXCESSIVE HEAT WARNING until 7 PM CDT this evening FOR ILZ042-
047>054-056-061>063-066>068-071>073.
HEAT ADVISORY until 7 PM CDT this evening FOR ILZ043>046-055-057.
&&
$$
SHORT TERM...SHIMON
LONG TERM...GEELHART
AVIATION...SHIMON
AREA FORECAST DISCUSSION
NWS TOPEKA KS
645 AM CDT Tue Aug 26 2014
...Update to aviation forecast discussion...
.SHORT TERM...(Today and Tonight)
Issued at 401 AM CDT TUE AUG 26 2014
Early this morning a broad mid-level ridge remained anchored over
the southeastern quadrant of the U.S. with a deepening mid-level
trough over the Great Basin area. With this pattern in place,
southwesterly flow aloft prevailed across the central U.S. with
water vapor imagery showing a few weak embedded shortwaves
developing across Kansas and Nebraska early this morning. At the
surface, low pressure was in place with a fairly stationary boundary
across south central Kansas and extending into northeast Kansas,
essentially bisecting the forecast area. With the support of a
stronger embedded shortwave, an MCS quickly developed across eastern
Nebraska early this morning and persisted through the overnight
hours as it was supported by the low-level jet and decent isentropic
lift. A weaker shortwave was noted across central Kansas, which
sparked a cluster of showers and thunderstorms overnight. However,
this activity was gradually weakening as outflow boundaries
continued to gust out ahead of the storms. As a result, local radar
showed several outflow boundaries situated across the region from
this activity. Mid-level clouds were in place over eastern Kansas,
providing better insolation and keeping temperatures more mild in
the mid/upper 70s. However, cooler conditions were noted over north
central Kansas as a result of the rain-cooled air, bringing
temperatures down into the mid 60s to low 70s.
The precipitation forecast continues to be a challenge in the short
term as we continue to deal with a stationary boundary over the
forecast area, passing weak embedded shortwaves, and lingering
outflow boundaries from overnight convection. The HRRR has been
handling the morning activity fairly well and shows the
precipitation lifting northward and becoming more focused near the
Kansas/Nebraska border before finally diminishing by mid to late
morning. However, there is uncertainty with whether or not any
additional convection will develop near the stationary boundary
and/or along any of the lingering outflow boundaries this afternoon. While a
few models are hinting at this redevelopment, they vary with regards
to the location of the precipitation. At this time, have increasing
PoPs during the afternoon hours into this evening across the
northern half of the forecast area. A stronger embedded shortwave
may once again track across north central Kansas into Nebraska late
tonight, supporting overnight convection primarily near the
Kansas/Nebraska border. While the potential for severe weather is
low, cannot rule out some strong wind gusts and locally heavy rain.
With this set-up in place, temperatures are also a challenge for
today as they will be greatly affected by any precipitation that
develops. In general, expect slightly cooler conditions across far
northern Kansas where precipitation may linger this morning and
potentially redevelop this afternoon. However, conditions may still
heat up across east central Kansas as this region may stay mostly
dry through the day. Afternoon highs in this area could reach into
the mid/upper 90s with heat indices reaching into the 100 to 103
degree range. This area may be close to heat advisory criteria, but
due to the uncertainty in the development of any afternoon
convection, have not issued one at this time but will need to
closely monitor through the day. Low temperatures tonight are
expected to drop into the upper 60s north to low 70s south.
.LONG TERM...(Wednesday through Monday)
Issued at 401 AM CDT TUE AUG 26 2014
Wednesday will likely see an ongoing MCS across Nebraska as models
focus on areas north of the Kansas border. Expect outflow boundaries
to be present across the northern CWA and possibly some ongoing
convection through the morning hours. Left over boundaries may also
be a focus for additional development in the afternoon as well.
Wednesday night into Thursday energy will eject out of the Rockies
trough across western Kansas and Nebraska this along with the low
level jet should fuel yet another MCS across the Plains mainly
across Nebraska. Western Kansas convection will move east into the
CWA Wednesday night and into Thursday morning. Additionally Nebraska
MCS could also clip the northern counties and have maintained
highest probabilities of showers and thunderstorms to the north of
I-70.
The models slowly move the upper trough across the Rockies and
Plains as it is cut off from the westerlies. The 00Z GFS and the 00Z
ECMWF continue to be in agreement with the speed of the trough
through the end of the week while the GFS ensemble mean is just a
tad faster as is the GEM with the passage of the trough axis across
eastern Kansas and western Missouri. Front should move into central
Kansas Thursday night into Friday then progress slowly across
eastern Kansas through Saturday. The front will be a focus for
convection as well as locally heavy rainfall as precipitable water
values of 1.50 to 2.00 inches will be in place. Good moisture
transport will continue each night across the plains as the low
level jet increases and larger scale ascent increases with the
approach of the upper trough. Some convection may linger into Sunday
in the east with another chance of thunderstorms late Sunday night
and into Monday as a wave moves through the Zonal flow across the
Central Plains. Temperatures will gradually cool by the end of the
week with Wednesday being the warmest day especially south of I-70.
Near normal temperatures in the upper 80s to lower 90s are expected
from Thursday through Monday.
&&
.AVIATION...(For the 12Z TAFs through 12Z Wednesday Morning)
Issued at 644 AM CDT TUE AUG 26 2014
For the 12z TAFs, winds have shifted to the north with the stalled
front positioned near the TAF sites. These winds should veer toward
the southeast through the day as the boundary shifts a bit further
north. Scattered showers and thunderstorms have developed north and
west of KMHK and expect this scattered pop-up activity to continue
to develop near KMHK through mid to late morning. There is the
potential for showers and thunderstorms to redevelop this afternoon
along lingering boundaries from the early morning convection,
however there is too much uncertainty with regards to location let
alone occurrence to warrant a mention in the TAFs at this time, but
this potential will need to be monitored closely in future updates.
&&
.TOP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...Hennecke
LONG TERM...53
AVIATION...Hennecke
AREA FORECAST DISCUSSION
NWS LOUISVILLE KY
1126 AM EDT Tue Aug 26 2014
...Forecast Update...
Issued at 1125 AM EDT Tue Aug 26 2014
Forecast is largely on track this morning, although did make an
update to add some isolated showers or a storm west of the I-65
corridor. Current analysis shows dew points starting to pool in this
area on the western edge of the surface high. SPC mesoanalysis
moisture convergence parameter also confirms this. Additionally,
have support from the HRRR that isolated to widely scattered
showers/storms should pop up by early afternoon.
Forecast soundings indicate at least moderately strong instability
will be available this afternoon due to the very moist low levels
combined with steep low level lapse rates. Deep layer flow is quite
weak, so only expect localized gusty winds in the vicinity of
showers/storms and some brief heavy rainfall.
.SHORT TERM (Now through Wednesday)...
Issued at 317 AM EDT Tue Aug 26 2014
Morning IR satellite and surface observations reveal mostly clear
skies across southern Indiana and central Kentucky. Some patchy fog
has developed in the typical fog prone areas and in areas that
picked up a bit of rainfall Monday afternoon. Temperatures remained
quite mild with readings in the lower-middle 70s. Expect quiet
weather to continue through the remainder of the overnight hours
with overnight minimums dropping only a few more degrees or so.
For Today/Tonight, the short term multi-model consensus continues to
be in agreement with increasing the strength of the mid-level ridge
axis overhead. This should result in another mostly sunny and muggy
day across the region. With some additional mid-level warming and
slight drying of the column, current thinking is that convection
will be a bit more isolated. However, high resolution convective
allowing models suggest that storms will fire up to our north along
the periphery of the ridge axis. These could slide southward in the
afternoon and affect our far northern areas of southern Indiana.
Thus, have maintained an isolated storm chance up that way for the
late afternoon hours. Afternoon highs will be similar to Monday
with readings in the upper 80s to the lower 90s. Skies are expected
to clear back out tonight as any convection dissipates after
sunset. Overnight lows will cool into the upper 60s in the far NE
to the lower 70s in the central and southwest.
For Wednesday, the upper level ridge axis is expected to shift a bit
further to the south along with the surface ridge axis. This will
allow a surface frontal boundary to sag southward through central
Indiana. Convection is expected to develop during the afternoon
hours along this front and this activity may eventually spread
southward into southern Indiana and the northern half of KY. For
now, isolated-scattered PoPs still look like a good bet at this
time. Afternoon highs will be warm once again with readings topping
out in the upper 80s in the north with lower 90s in the south.
.LONG TERM (Wednesday Night through Monday)...
Issued at 307 AM EDT Tue Aug 26 2014
Ridging across the southeastern United States will slowly shift
eastward through the long term. As it does so a shortwave trough
will approach from the west, moving across the upper Midwest Sunday
and across the Great Lakes region by Monday morning. At the surface
a weak frontal boundary near the KY/TN border at the beginning of
the period will eventually push back northward as a warm front
Friday.
For Wednesday night a few residual showers or storms may be ongoing
at the start of the period. However, these should dissipate
overnight with mostly dry conditions expected. Diurnal storms are
expected once again on Thursday and Friday, particularly in the
vicinity of the frontal boundaries. The better chance will be on
Thursday with scattered storms across the region. Friday`s storms
look to be more isolated in nature.
Rain chances will increase through the weekend as the upper level
trough nears and its associated surface low lifts north of the
region. The best chances for storms this weekend looks to be on
Sunday as precipitable water values rise to around 1.9 inches and we
become moderately unstable. Will keep chances in the 40-50% range
right now considering there is still some differences in the
development of the system between the model solutions. Monday will
see a return to the more summertime diurnal pattern of storms before
a cold front approaches towards midweek.
Temperatures will be in the upper 80s to lower 90s through Saturday
with lows in the upper 60s to lower 70s. With rain and clouds
expected Sunday into Monday we should see a bit of a cool down,
particularly on Sunday with highs in the lower to mid 80s expected.
This will not last however, as a return to upper 80s is expected by
Tuesday.
&&
.AVIATION (12Z TAF Update)...
Issued at 650 AM EDT Tue Aug 26 2014
Other than a period of VLIFR/LIFR at KBWG due to locally dense fog,
VFR conditions are expected at the terminals through the upcoming
period. Expect visibilities to return back to VFR at KBWG by
26/14Z. Elsewhere, mostly sunny skies and light northeast winds
will be seen at the terminals. Some isolated convection will be
possible this afternoon...mainly across southern Indiana. These may
threaten the KSDF terminal this afternoon...but the expected sparse
coverage precludes a mention in the TAF at this time.
&&
.LMK WATCHES/WARNINGS/ADVISORIES...
KY...NONE.
IN...NONE.
&&
$$
Update.........BJS
Short Term.....MJ
Long Term......EER
Aviation.......MJ
AREA FORECAST DISCUSSION
NWS SHREVEPORT LA
1040 AM CDT TUE AUG 26 2014
.DISCUSSION...
WV IMAGERY CLEARLY DEPICTS THE TUTT CURRENTLY CHURNING ACROSS THE
NRN GULF COAST. THIS DISTURBANCE MAY HELP TO KICK OFF SOME
CONVECTION THIS AFTN...ALTHOUGH MODELS NOT DEPICTING MUCH IN THE
WAY OF COVERAGE. CONSIDERING THE LACK OF CU DEVELOPMENT ACROSS
MUCH OF THE REGION THUS FAR...HAVE LOWERED THE 30 POPS ACROSS DEEP
E TX TO 20S. HAVE ALSO TWEAKED THE SKY GRIDS...BUT OTHERWISE...THE
GRIDS ARE IN GOOD SHAPE. /12/
&&
AVIATION... LATEST VIS IMAGERY THIS MORNING SHOWS OUR INVERTED
TROUGH OR TUTT LOW ACROSS THE S LA COAST...NOT LOOKING NEARLY AS
DEFINED AS WAS THE CASE THIS TIME ON MONDAY. 12Z NAM OUTPUT NOT
NEARLY AS SUPPORTIVE OF PRECIP COVERAGE TODAY COMPARED TO PREVIOUS
RUNS. HAVING SAID THAT...LATEST HRRR STILL SUGGESTS ISOLATED
CONVECTION DEVELOPING BY EARLY AFTERNOON ACROSS PORTIONS OF THE
REGION BUT THE KEY WORD IS ISOLATED.
FOR THE 18Z TAF PACKAGE...WILL NOT MAKE MENTION OF VCSH/VCTS AS
COVERAGE WILL JUST BE TOO SPARSE. CU FIELD SHOULD DEVELOP OVER THE
NEXT COUPLE HOURS WITH HEIGHTS RANGING FROM 4-6KFT THROUGH THE
AFTERNOON. CU FIELD SHOULD QUICKLY DISSIPATE AFTER SUNSET.
KEPT MENTION OF PATCHY FOG IN AT THE MLU TERMINAL OVERNIGHT BUT
MUCH DRIER AIR FILTERING IN FROM THE EAST MAY DETOUR THAT FROM
OCCURRING. /13/
PREV DISCUSSION... /ISSUED 435 AM CDT TUE AUG 26 2014/
DISCUSSION...
CENTER OF THE UPPER RIDGE WILL REMAIN ANCHORED TO OUR NORTH TODAY
WITH A WEAK SHEAR AXIS STILL IN PLACE OVER OUR REGION WHERE A WWD
MOVING UPPER DISTURBANCE BROUGHT SHWRS AND TSTMS TO PARTS OF N LA
YESTERDAY. THE RIDGE WILL CONTINUE TO BE THE PRIMARY INFLUENCE ON
OUR WEATHER FOR THE SHORT TERM BUT EXPECT ANOTHER DAY OF WIDELY
SCATTERED CONVECTION...AS THE WEAK CENTER OF CIRCULATION WITH THE
UPPER LOW OFF THE SE LA COAST SLOWLY MEANDERS WWD ACROSS THE NRN
GULF. BASED ON THE PLACEMENT OF THESE UPPER LEVEL FEATURES...THE
BEST CHANCES FOR SEEING ANY PASSING SHWRS OR ISOLD TSTMS WILL BE
SOUTH OF THE I-30 CORRIDOR AND MORE SO ACROSS DEEP E TX INTO W
CNTRL LA WHERE LOW CHANCE POPS ARE STILL ALL WE CAN MANAGE ATTM.
TEMPERATURES WILL CONTINUE TO HOVER IN THE MID 90S FOR HIGHS OVER
THE NEXT FEW DAYS UNTIL THE RIDGE FINALLY BEGINS TO BREAK DOWN AND
SLIDE EWD ALONG THE SE COAST TOWARD THE END OF THE WORK WEEK.
THIS WILL HELP TO INCREASE SOUTHERLY FLOW OFF THE GULF AND
INCREASE OUR RAIN CHANCES BY THURSDAY AND ESPECIALLY INTO FRIDAY
AND THE WEEKEND AS A LONGWAVE TROF SHIFTS EWD FROM THE PLAINS.
HAVE MAINTAINED POPS IN THE CHANCE CATEGORY FOR NOW WITH THIS
SYSTEM BUT WILL LIKELY NEED TO GO HIGHER AS BETTER CONSENSUS IS
REACHED WITH THE LONG TERM PROGS...WHICH HAVE COME INTO BETTER
AGREEMENT ALTHOUGH THE ECMWF IS STILL A BIT WETTER THAN THE GFS
WITH QPF AMOUNTS. AT A MINIMUM...WE CAN EXPECT SOME BENEFICIAL
RAINFALL AND TEMPERATURES RETURNING TO SEASONAL AVERAGES THROUGH
THE END OF THE EXTENDED PERIOD. /19/
&&
.PRELIMINARY POINT TEMPS/POPS...
SHV 96 72 96 72 95 / 20 20 10 10 20
MLU 94 68 95 70 94 / 20 10 10 10 20
DEQ 94 71 95 69 93 / 20 10 10 10 20
TXK 94 72 95 69 93 / 20 10 10 10 20
ELD 94 69 96 68 94 / 20 10 10 10 20
TYR 96 74 96 73 95 / 20 20 10 10 20
GGG 96 71 96 73 95 / 20 20 10 10 20
LFK 95 73 96 74 94 / 20 20 20 10 30
&&
.SHV WATCHES/WARNINGS/ADVISORIES...
AR...NONE.
LA...NONE.
OK...NONE.
TX...NONE.
&&
$$
12
AREA FORECAST DISCUSSION
NWS SHREVEPORT LA
1018 AM CDT TUE AUG 26 2014
.AVIATION...
LATEST VIS IMAGERY THIS MORNING SHOWS OUR INVERTED TROUGH OR TUTT
LOW ACROSS THE S LA COAST...NOT LOOKING NEARLY AS DEFINED AS WAS
THE CASE THIS TIME ON MONDAY. 12Z NAM OUTPUT NOT NEARLY AS
SUPPORTIVE OF PRECIP COVERAGE TODAY COMPARED TO PREVIOUS RUNS.
HAVING SAID THAT...LATEST HRRR STILL SUGGESTS ISOLATED CONVECTION
DEVELOPING BY EARLY AFTERNOON ACROSS PORTIONS OF THE REGION BUT
THE KEY WORD IS ISOLATED.
FOR THE 18Z TAF PACKAGE...WILL NOT MAKE MENTION OF VCSH/VCTS AS
COVERAGE WILL JUST BE TOO SPARSE. CU FIELD SHOULD DEVELOP OVER THE
NEXT COUPLE HOURS WITH HEIGHTS RANGING FROM 4-6KFT THROUGH THE
AFTERNOON. CU FIELD SHOULD QUICKLY DISSIPATE AFTER SUNSET.
KEPT MENTION OF PATCHY FOG IN AT THE MLU TERMINAL OVERNIGHT BUT
MUCH DRIER AIR FILTERING IN FROM THE EAST MAY DETOUR THAT FROM
OCCURRING.
13
&&
PREV DISCUSSION... /ISSUED 435 AM CDT TUE AUG 26 2014/
DISCUSSION...
CENTER OF THE UPPER RIDGE WILL REMAIN ANCHORED TO OUR NORTH TODAY
WITH A WEAK SHEAR AXIS STILL IN PLACE OVER OUR REGION WHERE A WWRD
MOVING UPPER DISTURBANCE BROUGHT SHWRS AND TSTMS TO PARTS OF N LA
YESTERDAY. THE RIDGE WILL CONTINUE TO BE THE PRIMARY INFLUENCE ON
OUR WEATHER FOR THE SHORT TERM BUT EXPECT ANOTHER DAY OF WIDELY
SCATTERED CONVECTION...AS THE WEAK CENTER OF CIRCULATION WITH THE
UPPER LOW OFF THE SE LA COAST SLOWLY MEANDERS WWRD ACROSS THE NRN
GULF. BASED ON THE PLACEMENT OF THESE UPPER LEVEL FEATURES...THE
BEST CHANCES FOR SEEING ANY PASSING SHWRS OR ISOLD TSTMS WILL BE
SOUTH OF THE I-30 CORRIDOR AND MORE SO ACROSS DEEP E TX INTO W
CNTRL LA WHERE LOW CHANCE POPS ARE STILL ALL WE CAN MANAGE ATTM.
TEMPERATURES WILL CONTINUE TO HOVER IN THE MID 90S FOR HIGHS OVER
THE NEXT FEW DAYS UNTIL THE RIDGE FINALLY BEGINS TO BREAK DOWN AND
SLIDE EWRD ALONG THE SE COAST TOWARD THE END OF THE WORK WEEK.
THIS WILL HELP TO INCREASE SOUTHERLY FLOW OFF THE GULF AND
INCREASE OUR RAIN CHANCES BY THURSDAY AND ESPECIALLY INTO FRIDAY
AND THE WEEKEND AS A LONGWAVE TROF SHIFTS EWRD FROM THE PLAINS.
HAVE MAINTAINED POPS IN THE CHANCE CATEGORY FOR NOW WITH THIS
SYSTEM BUT WILL LIKELY NEED TO GO HIGHER AS BETTER CONSENSUS IS
REACHED WITH THE LONG TERM PROGS...WHICH HAVE COME INTO BETTER
AGREEMENT ALTHOUGH THE ECMWF IS STILL A BIT WETTER THAN THE GFS
WITH QPF AMOUNTS. AT A MINIMUM...WE CAN EXPECT SOME BENEFICIAL
RAINFALL AND TEMPERATURES RETURNING TO SEASONAL AVERAGES THROUGH
THE END OF THE EXTENDED PERIOD. /19/
&&
.PRELIMINARY POINT TEMPS/POPS...
SHV 96 72 96 72 95 / 20 20 10 10 20
MLU 94 68 95 70 94 / 20 10 10 10 20
DEQ 94 71 95 69 93 / 20 10 10 10 20
TXK 94 72 95 69 93 / 20 10 10 10 20
ELD 94 69 96 68 94 / 20 10 10 10 20
TYR 96 74 96 73 95 / 20 20 10 10 20
GGG 96 71 96 73 95 / 20 20 10 10 20
LFK 95 73 96 74 94 / 30 20 20 10 30
&&
.SHV WATCHES/WARNINGS/ADVISORIES...
AR...NONE.
LA...NONE.
OK...NONE.
TX...NONE.
&&
$$
13
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
753 AM EDT TUE AUG 26 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 501 AM EDT TUE AUG 26 2014
PER WATER VAPOR IMAGERY AND RUC ANALYSIS...VIGOROUS SHORTWAVE THAT
WAS MOVING INTO SRN MANITOBA 24HRS AGO IS NOW MUCH WEAKER AND
TRACKING THRU NRN ONTARIO. ASSOCIATED COLD FRONT SWEPT ACROSS UPPER
MI DURING THE NIGHT...USHERING IN MUCH DRIER AIR. SFC DWPTS THAT
WERE IN THE 60S TO AROUND 70F ARE NOW DOWN IN THE MORE COMFORTABLE
50S AT NEARLY ALL LOCATIONS. UPSTREAM...QUITE A BIT OF CLOUD COVER IS
NOTED ACROSS THE NRN HALF OF MN...AND THERE HAVE EVEN BEEN A FEW
-SHRA/SPRINKLES IN NE MN. IN THE LAST FEW HRS...THE CLOUDS HAVE BEEN
THINNING OUT...AND RECENTLY THE CLOUDS HAVE SPREAD INTO WRN UPPER
MI. THESE CLOUDS ARE SITUATED IN THE 850MB THERMAL TROF WHICH HAS
850MB TEMPS AS LOW AS 4-5C OVER FAR NRN MN.
TODAY...850MB TROF SHIFTS INTO THE UPPER GREAT LAKES. WITH ONSET OF
DAYTIME HEATING COINCIDING WITH ARRIVAL OF THERMAL TROF...THERE
SHOULD BE AN EXPANSION OF SCT/BKN CU/STRATOCU FOR A TIME...
ESPECIALLY ACROSS THE N. DURING THE MID AND LATE AFTN...THE CLOUDS
SHOULD BEGIN TO DISSIPATE. FCST SOUNDINGS SUPPORT MAX TEMPS IN THE
UPPER 60S TO MID 70S...WARMEST SOUTH CENTRAL. WILL BE A BIT COOLER
WHERE WINDS ARE OFF LAKE SUPERIOR.
TONIGHT...SFC HIGH PRES BUILDS INTO THE WRN GREAT LAKES. HOWEVER...
SHORTWAVE TROF NOW OVER SASKATCHEWAN/MT IS FCST TO SHIFT E...
REACHING THE UPPER GREAT LAKES BY 12Z WED. SOME MODELS SHOW LIGHT
PCPN STREAKING E INTO WI AND EVEN INTO UPPER MI. INITIALLY...PCPN
DEVELOPMENT OUT OVER THE NRN PLAINS APPEARS TIED TO RIGHT ENTRANCE
OF JET STREAK ACROSS THE FAR NRN PLAINS. HOWEVER...WITH THE JET
TRANSLATING E OVER THE UPPER GREAT LAKES...JET FORCING WILL BE S OF
THE FCST AREA TONIGHT. IN ADDITION...LITTLE/NO DEEP LAYER FORCING IS
NOTED WITH SHORTWAVE...AND LOW-LEVELS ARE DRYING OUT TODAY. SO...IF
PCPN DOES MANAGE TO STREAK INTO THE AREA...THE LIGHT PCPN WOULD
LIKELY DRY UP BEFORE MAKING IT TO THE GROUND. THUS...NO MENTION OF
PCPN WAS INCLUDED IN FCST TONIGHT. AN INCREASE IN CLOUDS WILL KEEP
TEMPS FROM FALLING AS MUCH AS THEY COULD. OPTED FOR THE MIDDLE
GROUND OF AVBL GUIDANCE...RESULTING IN MIN TEMPS MOSTLY IN THE UPPER
40S/LWR 50S.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 346 AM EDT TUE AUG 26 2014
A SHORTWAVE WILL BE SLIDING EAST ACROSS THE CENTRAL/EASTERN CWA TO
START THE LONG TERM PERIOD WITHIN THE WEST-NORTHWEST FLOW ALOFT.
THERE IS A LITTLE POCKET OF MOISTURE BETWEEN 700-500MB ASSOCIATED
WITH THIS WAVE THAT WILL TRY TO KICK OFF SOME SHOWERS OVER THE
EASTERN CWA FOR THE FIRST COUPLE HOURS ON WEDNESDAY MORNING. WITH
DRY AIR BELOW 700MB DUE TO HIGH PRESSURE CENTERED NEAR DULUTH AT
12Z WEDNESDAY...THINK ANY PRECIPITATION THAT OCCURS WILL EVAPORATE
BEFORE REACHING THE SURFACE. BEHIND THIS WAVE...UPPER RIDGING WILL
DEVELOP AND ALLOW THE HIGH TO SHIFT EAST ACROSS THE CWA THROUGH
THURSDAY MORNING. THIS DRY AIR WILL LEAD TO MOSTLY CLEAR SKIES
ACROSS MUCH OF THE CWA...BUT THERE COULD BE SOME DIURNAL CLOUD
DEVELOPMENT WEDNESDAY AFTERNOON (INLAND AND TOWARDS WISCONSIN
BORDER) AFTER THE MID CLOUDS DEPART DURING THE MORNING. HIGHS WILL
BE BELOW NORMAL ON WEDNESDAY SINCE 850MB TEMPS IN THE MODELS ARE
AVERAGING AROUND 6-7C AND KEEPING HIGHS IN THE MID-UPPER 60S FOR
MOST LOCATIONS. LOWS WEDNESDAY NIGHT COULD GET CHILLY WITH THE
LIGHT WINDS...CLEAR SKIES...AND PWAT VALUES ABOUT 50 PERCENT OF
NORMAL. TRENDED LOWS DOWN INTO THE LOWER 40S OVER THE INTERIOR
LOCATIONS...AND EVEN HAVE SOME UPPER 30S FOR THE TRADITIONAL COLD
RAWS SITES.
THE AREA OF HIGH PRESSURE WILL DRIFT TO THE EAST ON THURSDAY AS THE
FIRST OF A SERIES OF SHORTWAVES LIFTS NORTHEAST OUT OF THE CENTRAL
ROCKIES/PLAINS THURSDAY AFTERNOON INTO THURSDAY NIGHT. AS HAS BEEN
THE CASE FOR THE LAST COUPLE DAYS...SEEMS LIKE BEST OPPORTUNITY FOR
RAIN WILL BE OVER THE SOUTHEAST HALF OF THE CWA. THESE SHOWERS
COULD LINGER INTO FRIDAY OVER THE SAME AREA BEFORE THE NEXT WAVE
SLIDES NORTHEAST TOWARDS THE AREA ON FRIDAY NIGHT. ONCE
AGAIN...BEST CHANCES WILL BE OVER THE SOUTHEAST PART OF THE
AREA...BUT LIKELY MORE CONFINED TO NEAR THE LAKE MICHIGAN
SHORELINE. WHILE THAT WAVE IS MOVING THROUGH...A WEAK SURFACE
TROUGH WILL SLOWLY DROP SOUTHEAST ACROSS THE CWA ON SATURDAY. THINK
PRECIP CHANCES WITH THIS PASSING TROUGH WILL BE LIMITED DUE TO
SHALLOW MOISTURE AND LIMITED UPPER LEVEL SUPPORT...THUS WILL KEEP
POPS FOR MOST AREAS IN THE SLIGHT CHANCE CATEGORY. BEHIND THAT
TROUGH...A HIGH PRESSURE RIDGE WILL MOVE OVER THE CWA SATURDAY
NIGHT AND REMAIN THROUGH SUNDAY NIGHT...AS THE PARENT HIGH SLIDES
SOUTHEAST ACROSS NORTHERN ONTARIO.
A STRONGER UPPER TROUGH WILL APPROACH THE AREA FOR THE FIRST PART
OF NEXT WEEK. A LOW PRESSURE SYSTEM ASSOCIATED WITH THIS UPPER
TROUGH WILL BE MOVING THROUGH SOUTHERN CANADA AND ALLOW SOUTHERLY
FLOW TO INCREASE OVER THE AREA SUNDAY NIGHT INTO MONDAY. THIS WILL
LEAD TO ABOVE NORMAL TEMPERATURES ON MONDAY AHEAD OF THE COLD FRONT
THAT MOVES THROUGH MONDAY NIGHT INTO TUESDAY MORNING. WILL SHOW
INCREASING CHANCES FOR RAIN MONDAY INTO MONDAY NIGHT AS THE COLD
FRONT PASSES THROUGH.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z WEDNESDAY MORNING)
ISSUED AT 752 AM EDT TUE AUG 26 2014
SOME LOWER CLOUDS ARE ACCOMPANYING THERMAL TROF INTO THE UPPER
LAKES...AND THIS WILL YIELD OCNL MVFR CIGS AT KIWD/KSAW FOR THE NEXT
2-3 HRS. THEREAFTER...DAYTIME HEATING WILL HELP TO RAISE CLOUD
BASES...LEADING TO VFR CONDITIONS PREVAILING. VFR CONDITIONS WILL
PREVAIL AT KCMX THRU THE FCST PERIOD. GUSTY W WINDS WILL ALSO
CONTINUE AT KCMX TODAY.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 501 AM EDT TUE AUG 26 2014
EXPECT WESTERLY WINDS AS HIGH AS 15-25KT OVER MUCH OF LAKE SUPERIOR
TODAY...RESULTING FROM PRES GRADIENT BTWN LOW PRES WELL OFF TO THE
NE AND HIGH PRES APPROACHING FROM THE W. AS THE HIGH SETTLES OVER
THE UPPER GREAT LAKES LATER TONIGHT THRU EARLY THU...WINDS WILL DROP
OFF TO MOSTLY UNDER 15KT. ALTHOUGH THE HIGH PRES DEPARTS THU...WINDS
SHOULD REMAIN UNDER 20KT FRI/SAT EVEN WITH TROF DROPPING ACROSS THE
AREA EARLY SAT.
&&
.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 GRAND FORKS ND
932 AM CDT TUE AUG 26 2014
.UPDATE...
ISSUED AT 931 AM CDT TUE AUG 26 2014
UPDATED TO LINGER SOME LOW CLOUDS ACROSS NORTHWEST MN THROUGH THE
LATE MORNING. REST OF THE AREA SHOULD SEE ABUNDANT SUNSHINE AND
LIGHT WINDS. SHOULD BE SOME INCREASE IN CLOUDS ACROSS THE SOUTHERN
FA THIS AFTERNOON. MAIN QUESTION IS STILL WHETHER THERE WILL BE
ANY LIGHT SHOWERS THERE. AT THIS POINT SEE NO REASON TO CHANGE SO
WILL CONTINUE TO MONITOR INCOMING NEW MODEL DATA.
&&
.SHORT TERM...(TODAY THROUGH WEDNESDAY)
ISSUED AT 345 AM CDT TUE AUG 26 2014
TODAY...SURFACE HIGH PRESSURE CONTINUES TO PRESS OVER THE AREA
PRODUCING LIGHT WEST TO NORTHWEST FLOW...DRYING CONDITIONS AND
UNSEASONABLY COOL TEMPERATURES. RESIDUAL LOW CLOUDS ACROSS
NORTHERN MINNESOTA SHOULD SHIFT EASTWARD THROUGH THE MORNING AS
THE PARENT LOW PRESSURE SYSTEM CONTINUES ITS FAST BREAK ACROSS
NORTHERN ONTARIO AND JAMES BAY. EXPECT GENERALLY FAIR SKIES ACROSS
MOST OF THE AREA THROUGH MIDDAY TODAY...WITH INCREASING MIDDLE TO
LOWER LEVEL MOISTURE MOVING FROM NCNTRL SD INTO SOUTHEAST ND AND
WEST CENTRAL MN THROUGH THE LATER AFTERNOON. AN ISOLATED SHOWER OR
TWO IS POSSIBLE LATE THIS AFTERNOON ACROSS FAR SOUTHERN PORTIONS
OF THE RED RIVER BASIN. FOR NOW...THE RUC SEEMS A BIT OVERLY
AGGRESSIVE WIT THIS FEATURE...WHILE HRRR AND NAM PREFER A SOMEWHAT
STRONGER SFC HIGH PRESSURE OVER NORTHERN MINNESOTA...KEEPING MOST
OF THE PRECIP THREAT WELL TO OUR SOUTH.
TONIGHT AND WEDNESDAY...A FLAT SURFACE RIDGE STAYS DRAPED FROM
THE WESTERN GREAT LAKES...AND ACROSS NORTH DAKOTA INTO EASTERN MT.
SOUTHERLY FLOW INCREASES THROUGH THE DAY ON WEDNESDAY PROMISING
SOME REBOUNDING TEMPERATURES...WHILE DEEP MOISTURE STAYS TRAPPED
FOR ANOTHER DAY BY A STATIONARY SURFACE BOUNDARY ACROSS SOUTHERN
SD AND NRN IA.
.LONG TERM...(WEDNESDAY NIGHT THROUGH MONDAY)
ISSUED AT 345 AM CDT TUE AUG 26 2014
WEDNESDAY NIGHT AND THURSDAY...INCREASING LOW LEVEL SOUTHERLY
FLOW FROM WEDNESDAY EVENING INTO THURSDAY COULD BRING A BAND OF
MOIST AIR THROUGH EASTERN SD INTO WEST CENTRAL MN...WITH SCT
THUNDERSTORMS BRUSHING AGAINST THE SOUTHEAST EDGE OF THE RED RIVER
BASIN. HAVE STUCK WITH THE NAM AND WITH WPC CONTINUITY IN KEEPING
THE FORECAST DRY FOR THIS PERIOD WHILE THE 00Z GFS HAS BEEN
SOMETHING OF THE WET OUTLIER SOLN.
FRIDAY THROUGH MONDAY...LOW AMPLITUDE LONG WAVE TROUGH OVER THE
GULF OF AK MOVES TO CENTRAL CANADA BY THE END OF THE PERIOD.
ESSENTIALLY ZONAL FLOW REMAINS ACROSS SOUTHERN CANADA AND THE
NORTHERN STATES THROUGH THE PERIOD. ZONAL PATTERN SHIFTS SLOWLY
SOUTH BY THE END OF THE PERIOD. GFS AND ECMWF WERE IN GOOD
AGREEMENT THROUGH 84 HOURS WITH THE UPPER AIR. HOWEVER WITH THE
SURFACE FEATURES THE GFS WAS FAST AT 84 HOURS. THE GFS REMAINS
FASTER THAN THE ECMWF AT DAY 7. WILL BLEND THE ECMWF AND THE GFS.
LITTLE CHANGE TO TEMPS....INCREASES TEMPS A DEGREE OR SO FOR FRI AND
DECREASE A DEGREE OR SO FOR SAT. NO CHANGE TO SUN AND MON.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z TUESDAY NIGHT)
ISSUED AT 640 AM CDT TUE AUG 26 2014
GENERALLY FAIR SKIES ACROSS ERN ND WITH AREAS VFR CIGS REMAINING
IN NORTHWEST MN. PATCHY FOG IN THE DEVILS LAKE BASIN SHOULD
DISSIPATE QUICKLY WITH SUNRISE. THROUGH THE MORNING EXPECT CONTINUED
DECREASE IN CLOUD COVER NORTHWEST MN... WITH LINGERING BROKEN CIGS
OVER THE LAKE OF THE WOODS AND RED LAKES REGION THROUGH MID
MORNING. LATE AFTERNOON WILL SEE INCREASING MID LEVEL CLOUDS
ACROSS FAR SOUTHEAST ND...WITH SCT VFR CIGS AND RAIN SHOWERS
POSSIBLE THERE.
&&
.FGF WATCHES/WARNINGS/ADVISORIES...
ND...NONE.
MN...NONE.
&&
$$
UPDATE...GODON
SHORT TERM...GUST
LONG TERM...GUST/HOPPES
AVIATION...GUST
AREA FORECAST DISCUSSION
NWS GRAND FORKS ND
640 AM CDT TUE AUG 26 2014
.UPDATE...
ISSUED AT 640 AM CDT TUE AUG 26 2014
SO SIG CHANGES TO THE PACKAGE THUS FAR. LOW CLOUDS ACROSS
NORTHWEST MN CONTINUE TO SHIFT EASTWARD AND ERODE. PATCHY FOG IN
THE DEVILS LAKE BASIN EXPECTED TO DISSIPATE QUICKLY WITH SUNRISE.
&&
.SHORT TERM...(TODAY THROUGH WEDNESDAY)
ISSUED AT 345 AM CDT TUE AUG 26 2014
TODAY...SURFACE HIGH PRESSURE CONTINUES TO PRESS OVER THE AREA
PRODUCING LIGHT WEST TO NORTHWEST FLOW...DRYING CONDITIONS AND
UNSEASONABLY COOL TEMPERATURES. RESIDUAL LOW CLOUDS ACROSS
NORTHERN MINNESOTA SHOULD SHIFT EASTWARD THROUGH THE MORNING AS
THE PARENT LOW PRESSURE SYSTEM CONTINUES ITS FAST BREAK ACROSS
NORTHERN ONTARIO AND JAMES BAY. EXPECT GENERALLY FAIR SKIES ACROSS
MOST OF THE AREA THROUGH MIDDAY TODAY...WITH INCREASING MIDDLE TO
LOWER LEVEL MOISTURE MOVING FROM NCNTRL SD INTO SOUTHEAST ND AND
WESTCENTRAL MN THROUGH THE LATER AFTERNOON. AN ISOLATED SHOWER OR
TWO IS POSSIBLE LATE THIS AFTERNOON ACROSS FAR SOUTHERN PORTIONS
OF THE RED RIVER BASIN. FOR NOW...THE RUC SEEMS A BIT OVERLY
AGGRESSIVE WIT THIS FEATURE...WHILE HRRR AND NAM PREFER A SOMEWHAT
STRONGER SFC HIGH PRESSURE OVER NORTHERN MINNESOTA...KEEPING MOST
OF THE PRECIP THREAT WELL TO OUR SOUTH.
TONIGHT AND WEDNESDAY...A FLAT SURFACE RIDGE STAYS DRAPED FROM
THE WESTERN GREAT LAKES...AND ACROSS NORTH DAKOTA INTO EASTERN MT.
SOUTHERLY FLOW INCREASES THROUGH THE DAY ON WEDNESDAY PROMISING
SOME REBOUNDING TEMPERATURES...WHILE DEEP MOISTURE STAYS TRAPPED
FOR ANOTHER DAY BY A STATIONARY SURFACE BOUNDARY ACROSS SOUTHERN
SD AND NRN IA.
.LONG TERM...(WEDNESDAY NIGHT THROUGH MONDAY)
ISSUED AT 345 AM CDT TUE AUG 26 2014
WEDNESDAY NIGHT AND THURSDAY...INCREASING LOW LEVEL SOUTHERLY
FLOW FROM WEDNESDAY EVENING INTO THURSDAY COULD BRING A BAND OF
MOIST AIR THROUGH EASTERN SD INTO WESTCENTRAL MN...WITH SCT
THUNDERSTORMS BRUSHING AGAINST THE SOUTHEAST EDGE OF THE RED RIVER
BASIN. HAVE STUCK WITH THE NAM AND WITH WPC CONTINUITY IN KEEPING
THE FORECAST DRY FOR THIS PERIOD WHILE THE 00Z GFS HAS BEEN
SOMETHING OF THE WET OUTLIER SOLN.
FRIDAY THROUGH MONDAY...LOW AMPLITUDE LONG WAVE TROUGH OVER THE
GULF OF AK MOVES TO CENTRAL CANADA BY THE END OF THE PERIOD.
ESSENTIALLY ZONAL FLOW REMAINS ACROSS SOUTHERN CANADA AND THE
NORTHERN STATES THROUGH THE PERIOD. ZONAL PATTERN SHIFTS SLOWLY
SOUTH BY THE END OF THE PERIOD. GFS AND ECMWF WERE IN GOOD
AGREEMENT THROUGH 84 HOURS WITH THE UPPER AIR. HOWEVER WITH THE
SURFACE FEATURES THE GFS WAS FAST AT 84 HOURS. THE GFS REMAINS
FASTER THAN THE ECMWF AT DAY 7. WILL BLEND THE ECMWF AND THE GFS.
LITTLE CHANGE TO TEMPS....INCREASES TEMPS A DEGREE OR SO FOR FRI AND
DECREASE A DEGREE OR SO FOR SAT. NO CHANGE TO SUN AND MON.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z TUESDAY NIGHT)
ISSUED AT 640 AM CDT TUE AUG 26 2014
GENERALLY FAIR SKIES ACROSS ERN ND WITH AREAS VFR CIGS REMAINING
IN NORTHWEST MN. PATCHY FOG IN THE DEVILS LAKE BASIN SHOULD
DISSATE QUICKLY WITH SUNRISE. THROUGH THE MORNING EXPECT CONTINUED
DECREASE IN CLOUD COVER NORTHWEST MN... WITH LINGERING BROKEN CIGS
OVER THE LAKE OF THE WOODS AND RED LAKES REGION THROUGH MID
MORNING. LATE AFTERNOON WILL SEE INCREASING MID LEVEL CLOUDS
ACROSS FAR SOUTHEAST ND...WITH SCT VFR CIGS AND RAIN SHOWERS
POSSIBLE THERE.
&&
.FGF WATCHES/WARNINGS/ADVISORIES...
ND...NONE.
MN...NONE.
&&
$$
UPDATE...GUST
SHORT TERM...GUST
LONG TERM...GUST/HOPPES
AVIATION...GUST
AREA FORECAST DISCUSSION
NWS HOUSTON/GALVESTON TX
946 AM CDT TUE AUG 26 2014
.DISCUSSION...
STORMS HAVE DISSIPATED OVER LAND BUT SHOULD RETURN THIS AFTERNOON
AS TEMPERATURES REACH 88-91 DEGREES. A LITTLE BIT OF THE DRIER AIR
TO THE NORTHEAST CAN BE SEEN IN THE AM AMDAR SOUNDINGS BUT CLOSER
TO THE COAST MORE MOISTURE IS PRESENT AND SHOULD SUPPORT A CHANCE
OF SHOWERS AND THUNDERSTORMS STORM MOTIONS WILL BE SLOW AND MAINLY
FROM NORTHEAST TO SOUTHWEST THOUGH CLOSER TO THE COAST SLOWER YET
AND MAY EVEN BE STATIONARY ALONG THE SEABREEZE AS IT TRIES TO PUSH
INLAND. MADE SOME CHANGES TO THE SKY COVER AS MUCH OF THE AREA HAS
GONE MS/PC BUT AGAIN THIS WILL CHANGE BACK TO PC/MC WITH CONTINUED
HEATING. AREAS IN THE WEST WILL BE THE WARMEST TODAY AND COULD SEE
HIGHS OF 95-98 WITH THE CORRESPONDING HIGHER HEAT INDEX READINGS
OF 100-104.
NHC HAS GIVEN THE DISTURBANCE IN THE GULF A 10 PERCENT CHANCE OF
DEVELOPMENT.
45
&&
.PREV DISCUSSION... /ISSUED 716 AM CDT TUE AUG 26 2014/
DISCUSSION...
UPDATED AVIATION DISCUSSION.
AVIATION...
VFR CONDITIONS CURRENTLY PREVAIL AT THE TAF SITES. A FEW SHOWERS
HAD POPPED UP WEST OF CLL AND ALONG AN AXIS SOUTH BUT THESE HAVE
DISSIPATED OVER THE PAST HOUR OR SO. ANOTHER CLUSTER OF SHOWERS
AND STORMS IS LOCATED MANLY OFFSHORE. TODAY EXPECT SHOWERS AND A
FEW THUNDERSTORMS TO PERCOLATE UP WITH DAYTIME HEATING AND
ENHANCED BY UPPER DISTURBANCE. GREATEST COVERAGE LOOKS TO BE AT
THE IMMEDIATE COAST SO HAVE GONE WITH TEMPO THUNDER AT GLS AND
LBX. FOR NEXT TIER NORTH...SGR AND HOU...HAVE GONE TEMPO SHRA AS
CAPE AND COVERAGE WILL BE MORE LIMITED BUT SHOWERS AND POSSIBLY AN
ISOLATED TSTRM WILL BE AROUND. FARTHER NORTH YET...AT CXO...UTS
AND CLL...CANT RULE OUT AN ISOLATED SHOWER...BUT MESO MODELS
SUGGEST LIMITED COVERAGE. FOR THOSE SITES THINK VCSH IS
APPROPRIATE. 46
PREV DISCUSSION... /ISSUED 444 AM CDT TUE AUG 26 2014/
DISCUSSION...
MORNING SFC ANALYSIS SHOWS FAIRLY WEAK PRESSURE GRADIENT ACROSS
MUCH OF TX WITH MAINLY E/SE WINDS ALONG THE UPPER TX COAST. WATER
VAPOR IMAGERY SHOWS A SHORT WAVE TROUGH MOVING ACROSS THE N GULF
TOWARDS SE TX. THE 00Z SOUNDING FROM LCH SHOWED 2.4 INCHES OF
PRECIP WATER WHICH IS QUITE HIGH FOR THIS TIME OF YEAR BEING 2 STD
DEV FROM NORMAL. GOES PRECIP WATER SOUNDER DATA SHOWS AT LEAST
THIS MUCH MOISTURE OVER A LARGE PORTION OF THE AREA. THIS BROAD
AREA OF DEEP MOISTURE EXTENDS FROM INLAND AREAS TO WELL OFF THE
COAST. SHORT RANGE MODELS ADVECT MUCH MORE MOIST AIRMASS INTO SE
TX WHICH MAKES SENSE BASED OFF 00Z LCH WIND PROFILE. THE NAM SEEMS
TO BE A BIT MORE AGGRESSIVE WITH BRINGING THE MOISTURE INTO THE
AREA WHERE GFS IS SLOWER. GFS IS ALSO FASTER IN BRINGING SOME
DRIER AIR INTO THE AREA FROM THE EAST. THIS MAY IMPACT
THUNDERSTORM CHANCES MID WEEK ESPECIALLY OVER NORTHERN PORTIONS OF
SE TX. FOR NOW RADAR SHOWS ACTIVITY ORGANIZING IN THE GULF AND
THIS WILL LIKELY BE THE BEGINNING OF THUNDERSTORM ACTIVITY ALONG
THE COAST. THINK 40/50 POPS LOOK ON TRACK FOR MUCH OF THE AREA FOR
THE REST OF THE WEEK. ON A CURIOUS NOTE...MESO MODELS SUCH AS WRF
ARW AND HRRR ARE NOT VERY ROBUST WITH CONVECTION FORMING UNTIL
MUCH LATER IN THE AFTERNOON. THIS BRINGS IN SOME DOUBT AS TO HOW
CONVECTION WILL EVOLVE TODAY.
UPPER LEVEL PATTERN WILL BE QUITE CONDUCIVE FOR CONVECTION. WATER
VAPOR IMAGERY SHOWS SHORTWAVE MOVING INTO SE TX FROM THE N GULF
TODAY AND FORECAST MODELS CONTINUE TO STALL THIS FEATURE ALONG THE
COAST OR JUST INLAND OF MIDDLE TX COAST ON WEDNESDAY. THIS MEANS
AN OVERALL WEAKNESS IN THE RIDGE WILL EXIST AND ONLY STRENGTHENED
BY BROAD TROUGH NOW OVER THE GREAT BASIN MOVING INTO THE PLAINS
FOR FRIDAY INTO SATURDAY. THE CUTOFF SHORTWAVE OR TUTT LOW WILL
THEN LIFT NORTH AS THE UPPER TROUGH STARTS TO MOVE THROUGH THE
PLAINS LATE FRI INTO SAT. AFTER THE TROUGH LIFTS OVERALL UPPER
LEVEL RIDGING OCCURS BUT THE RIDGE SEEMS TO BE STRETCHED OUT ALL
ALONG THE SOUTHERN TIER OF STATES.
THE OTHER MAJOR INGREDIENT FOR THUNDERSTORM CHANCES IS MOISTURE.
GOES SOUNDER PRECIP WATER PRODUCT SHOWS DEEP MOISTURE AXIS OR
ATMOSPHERIC MOISTURE RIVER COMING FROM THE CARIBBEAN INTO THE N
GULF. THIS PLUME OF MOISTURE WILL VARY IN ITS OVERALL MOISTURE
CONTENT FROM DAY TO DAY BUT IT WILL NOT TAKE MUCH TIME FOR
CONVECTION TO DEVELOP. MODEL SOUNDINGS SUPPORT CONVECTIVE TEMPS IN
THE UPPER 80S TO LOW 90S WITH PRECIP WATER VALUES AROUND 2.2 TO
2.4 INCHES. THIS MOISTURE PLUME REMAINING IN PLACE FOR THE NEXT
DAY OR TWO SHOULD SUPPORT CONTINUED THUNDERSTORM ACTIVITY ACROSS
THE AREA. WITH BREAKS IN CLOUD COVER THESE CONVECTIVE TEMPS LOOK
TO BE ACHIEVABLE EVEN IN THE LATE MORNING HOURS. IT LOOKS LIKE
TODAY INTO WEDNESDAY WILL CARRY THE HIGHEST CHANCES BUT EVEN 30/40
POPS LOOK REASONABLE FOR THE END OF THE WEEK.
CONVECTION AND CLOUD COVER SHOULD KNOCK TEMPS DOWN A COUPLE OF
DEGREES FROM THE LAST FEW DAYS. HIGH TEMPS WILL REACH LOW 90S
ALONG THE COAST AND POSSIBLY INLAND. MIN TEMPS MAY BE ABOVE
NORMAL WITH HIGHER MOISTURE ALONG THE COAST. LOW TEMPS WILL MAINLY
BE DRIVEN BY ANY OUTFLOW BOUNDARIES THAT MOVE THROUGH THE AREA.
MAIN IMPACTS FROM THIS CHANGE IN THE WEATHER PATTERN WILL BE
POSSIBILITY OF HEAVY RAINFALL ON ANY OF THE NEXT FEW DAYS. HIGHEST
RAINFALL TOTALS WILL LIKELY BE ALONG THE COAST AND OFFSHORE.
THAT`S NOT TO SAY A FEW STRONG STORMS COULD NOT FORM INLAND WHICH
COULD PRODUCE HEAVY RAINFALL. HOURLY RAIN RATES OF 1-2 INCHES AN
HOUR WOULD NOT BE OUT OF THE QUESTION SO ISO 1-3 INCH AMOUNTS
WOULD BE POSSIBLE. LOOKING AT GRIDDED FFG AND NASA SPORT LIS
DATA...IF ANYTHING MOST FLOOD PRONE AREAS WILL BE EAST OF
INTERSTATE 45 INTO E TX. AT THIS TIME ANY FLOODING PROBLEMS WILL
BE VERY LOCALIZED. OF COURSE URBAN AREAS WITH POOR DRAINAGE WILL
ALWAYS BE AN ISSUE ONCE RAIN RATES APPROACH 2 INCHES AN HOUR. THE
HARDEST PART OF THE FORECAST IS TRYING THE NARROW DOWN ANY ONE DAY
THAT WILL HAVE A HIGHER POTENTIAL FOR HEAVY RAINFALL. AT THIS TIME
THE NEXT 4 DAYS HAVE THAT POTENTIAL.
39
MARINE...
AN UPPER LEVEL DISTURBANCE WILL BRING SHOWERS AND THUNDERSTORMS
TO THE WATERS TODAY AND WEDNESDAY. FAIRLY LIGHT EAST TO SOUTHEAST
FLOW WILL BECOME MORE MODERATE...MAINLY IN THE 10 TO 15 KNOT
RANGE...LATER THIS AFTERNOON...AND CONTINUING THROUGH LATE IN THE
WEEK. THERE WILL BE AN INCREASE IN SEAS CORRESPONDING...INTO THE 2
TO 4 FEET RANGE FOR COASTAL WATERS.
46
&&
.PRELIMINARY POINT TEMPS/POPS...
COLLEGE STATION (CLL) 96 76 96 75 93 / 20 20 20 20 30
HOUSTON (IAH) 92 77 93 76 92 / 50 20 40 20 50
GALVESTON (GLS) 90 80 88 80 89 / 50 40 50 50 50
&&
.HGX WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
GM...NONE.
&&
$$
DISCUSSION...45
AREA FORECAST DISCUSSION
NWS HOUSTON/GALVESTON TX
716 AM CDT TUE AUG 26 2014
.DISCUSSION...
UPDATED AVIATION DISCUSSION.
&&
.AVIATION...
VFR CONDITIONS CURRENTLY PREVAIL AT THE TAF SITES. A FEW SHOWERS
HAD POPPPED UP WEST OF CLL AND ALONG AN AXIS SOUTH BUT THESE HAVE
DISSIPATED OVER THE PAST HOUR OR SO. ANOTHER CLUSTER OF SHOWERS
AND STORMS IS LOCATED MANLY OFFSHORE. TODAY EXPECT SHOWERS AND A
FEW THUNDERSTORMS TO PERCOLATE UP WITH DAYTIME HEATING AND
ENHANCED BY UPPER DISTURBANCE. GREATEST COVERAGE LOOKS TO BE AT
THE IMMEDIATE COAST SO HAVE GONE WITH TEMPO THUNDER AT GLS AND
LBX. FOR NEXT TIER NORTH...SGR AND HOU...HAVE GONE TEMPO SHRA AS
CAPE AND COVERAGE WILL BE MORE LIMITED BUT SHOWERS AND POSSIBLY AN
ISOLATED TSTRM WILL BE AROUND. FARTHER NORTH YET...AT CXO...UTS
AND CLL...CANT RULE OUT AN ISOLATED SHOWER...BUT MESO MODELS
SUGGEST LIMITED COVERAGE. FOR THOSE SITES THINK VCSH IS
APPROPRIATE. 46
&&
.PREV DISCUSSION... /ISSUED 444 AM CDT TUE AUG 26 2014/
DISCUSSION...
MORNING SFC ANALYSIS SHOWS FAIRLY WEAK PRESSURE GRADIENT ACROSS
MUCH OF TX WITH MAINLY E/SE WINDS ALONG THE UPPER TX COAST. WATER
VAPOR IMAGERY SHOWS A SHORT WAVE TROUGH MOVING ACROSS THE N GULF
TOWARDS SE TX. THE 00Z SOUNDING FROM LCH SHOWED 2.4 INCHES OF
PRECIP WATER WHICH IS QUITE HIGH FOR THIS TIME OF YEAR BEING 2 STD
DEV FROM NORMAL. GOES PRECIP WATER SOUNDER DATA SHOWS AT LEAST
THIS MUCH MOISTURE OVER A LARGE PORTION OF THE AREA. THIS BROAD
AREA OF DEEP MOISTURE EXTENDS FROM INLAND AREAS TO WELL OFF THE
COAST. SHORT RANGE MODELS ADVECT MUCH MORE MOIST AIRMASS INTO SE
TX WHICH MAKES SENSE BASED OFF 00Z LCH WIND PROFILE. THE NAM SEEMS
TO BE A BIT MORE AGGRESSIVE WITH BRINGING THE MOISTURE INTO THE
AREA WHERE GFS IS SLOWER. GFS IS ALSO FASTER IN BRINGING SOME
DRIER AIR INTO THE AREA FROM THE EAST. THIS MAY IMPACT
THUNDERSTORM CHANCES MID WEEK ESPECIALLY OVER NORTHERN PORTIONS OF
SE TX. FOR NOW RADAR SHOWS ACTIVITY ORGANIZING IN THE GULF AND
THIS WILL LIKELY BE THE BEGINNING OF THUNDERSTORM ACTIVITY ALONG
THE COAST. THINK 40/50 POPS LOOK ON TRACK FOR MUCH OF THE AREA FOR
THE REST OF THE WEEK. ON A CURIOUS NOTE...MESO MODELS SUCH AS WRF
ARW AND HRRR ARE NOT VERY ROBUST WITH CONVECTION FORMING UNTIL
MUCH LATER IN THE AFTERNOON. THIS BRINGS IN SOME DOUBT AS TO HOW
CONVECTION WILL EVOLVE TODAY.
UPPER LEVEL PATTERN WILL BE QUITE CONDUCIVE FOR CONVECTION. WATER
VAPOR IMAGERY SHOWS SHORTWAVE MOVING INTO SE TX FROM THE N GULF
TODAY AND FORECAST MODELS CONTINUE TO STALL THIS FEATURE ALONG THE
COAST OR JUST INLAND OF MIDDLE TX COAST ON WEDNESDAY. THIS MEANS
AN OVERALL WEAKNESS IN THE RIDGE WILL EXIST AND ONLY STRENGTHENED
BY BROAD TROUGH NOW OVER THE GREAT BASIN MOVING INTO THE PLAINS
FOR FRIDAY INTO SATURDAY. THE CUTOFF SHORTWAVE OR TUTT LOW WILL
THEN LIFT NORTH AS THE UPPER TROUGH STARTS TO MOVE THROUGH THE
PLAINS LATE FRI INTO SAT. AFTER THE TROUGH LIFTS OVERALL UPPER
LEVEL RIDGING OCCURS BUT THE RIDGE SEEMS TO BE STRETCHED OUT ALL
ALONG THE SOUTHERN TIER OF STATES.
THE OTHER MAJOR INGREDIENT FOR THUNDERSTORM CHANCES IS MOISTURE.
GOES SOUNDER PRECIP WATER PRODUCT SHOWS DEEP MOISTURE AXIS OR
ATMOSPHERIC MOISTURE RIVER COMING FROM THE CARIBBEAN INTO THE N
GULF. THIS PLUME OF MOISTURE WILL VARY IN ITS OVERALL MOISTURE
CONTENT FROM DAY TO DAY BUT IT WILL NOT TAKE MUCH TIME FOR
CONVECTION TO DEVELOP. MODEL SOUNDINGS SUPPORT CONVECTIVE TEMPS IN
THE UPPER 80S TO LOW 90S WITH PRECIP WATER VALUES AROUND 2.2 TO
2.4 INCHES. THIS MOISTURE PLUME REMAINING IN PLACE FOR THE NEXT
DAY OR TWO SHOULD SUPPORT CONTINUED THUNDERSTORM ACTIVITY ACROSS
THE AREA. WITH BREAKS IN CLOUD COVER THESE CONVECTIVE TEMPS LOOK
TO BE ACHIEVABLE EVEN IN THE LATE MORNING HOURS. IT LOOKS LIKE
TODAY INTO WEDNESDAY WILL CARRY THE HIGHEST CHANCES BUT EVEN 30/40
POPS LOOK REASONABLE FOR THE END OF THE WEEK.
CONVECTION AND CLOUD COVER SHOULD KNOCK TEMPS DOWN A COUPLE OF
DEGREES FROM THE LAST FEW DAYS. HIGH TEMPS WILL REACH LOW 90S
ALONG THE COAST AND POSSIBLY INLAND. MIN TEMPS MAY BE ABOVE
NORMAL WITH HIGHER MOISTURE ALONG THE COAST. LOW TEMPS WILL MAINLY
BE DRIVEN BY ANY OUTFLOW BOUNDARIES THAT MOVE THROUGH THE AREA.
MAIN IMPACTS FROM THIS CHANGE IN THE WEATHER PATTERN WILL BE
POSSIBILITY OF HEAVY RAINFALL ON ANY OF THE NEXT FEW DAYS. HIGHEST
RAINFALL TOTALS WILL LIKELY BE ALONG THE COAST AND OFFSHORE.
THAT`S NOT TO SAY A FEW STRONG STORMS COULD NOT FORM INLAND WHICH
COULD PRODUCE HEAVY RAINFALL. HOURLY RAIN RATES OF 1-2 INCHES AN
HOUR WOULD NOT BE OUT OF THE QUESTION SO ISO 1-3 INCH AMOUNTS
WOULD BE POSSIBLE. LOOKING AT GRIDDED FFG AND NASA SPORT LIS
DATA...IF ANYTHING MOST FLOOD PRONE AREAS WILL BE EAST OF
INTERSTATE 45 INTO E TX. AT THIS TIME ANY FLOODING PROBLEMS WILL
BE VERY LOCALIZED. OF COURSE URBAN AREAS WITH POOR DRAINAGE WILL
ALWAYS BE AN ISSUE ONCE RAIN RATES APPROACH 2 INCHES AN HOUR. THE
HARDEST PART OF THE FORECAST IS TRYING THE NARROW DOWN ANY ONE DAY
THAT WILL HAVE A HIGHER POTENTIAL FOR HEAVY RAINFALL. AT THIS TIME
THE NEXT 4 DAYS HAVE THAT POTENTIAL.
39
MARINE...
AN UPPER LEVEL DISTURBANCE WILL BRING SHOWERS AND THUNDERSTORMS
TO THE WATERS TODAY AND WEDNESDAY. FAIRLY LIGHT EAST TO SOUTHEAST
FLOW WILL BECOME MORE MODERATE...MAINLY IN THE 10 TO 15 KNOT
RANGE...LATER THIS AFTERNOON...AND CONTINUING THROUGH LATE IN THE
WEEK. THERE WILL BE AN INCREASE IN SEAS CORRESPONDING...INTO THE 2
TO 4 FEET RANGE FOR COASTAL WATERS.
46
&&
.PRELIMINARY POINT TEMPS/POPS...
COLLEGE STATION (CLL) 96 76 96 75 93 / 20 20 20 20 30
HOUSTON (IAH) 92 77 93 76 92 / 50 20 40 20 50
GALVESTON (GLS) 90 80 88 80 89 / 50 40 50 50 50
&&
.HGX WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
GM...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS FLAGSTAFF AZ
320 PM MST TUE AUG 25 2014
.SYNOPSIS...
A LOW PRESSURE TROUGH WILL CONTINUE TO BRING NUMEROUS SHOWERS AND
THUNDERSTORMS TO THE NORTHLAND TONIGHT. STORMS WILL DECREASE FROM
SOUTHWEST TO NORTHEAST OVERNIGHT...WITH 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...BRIEF DISCUSSION WITH ONGOING CONVECTIVE ACTIVITY...
NUMEROUS SHOWERS AND THUNDERSTORMS DEVELOPED OVER NORTHERN ARIZONA
TODAY...WITH THE STRONGEST ACTIVITY PERISTING SOUTH OF INTERSTATE 40
WHERE INSTABILITY HAS BEEN GREATEST. ACTIVITY HAS DIMINISHED OVER THE
PAST COUPLE HOURS OVER WESTERN AZ AS SUBSIDENCE AND DRIER AIR STARTS
TO WORK ON THE ATMOSPHERE...BUT EXPECT STORMS TO PERSIST AHEAD OF THE
SHORTWAVE AXIS WHERE INSTABILITY IN EXCESS OF 1000J/KG...AND 0-6KM
BULK SHEAR 30-40KTS WIND SHEAR STILL POSE A THREAT OF STRONG TO SVR
STORMS AND HEAVY RAINFALL. FLASH FLOOD WATCH TO CONTINUE AS ISSUED.
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 00Z PACKAGE...SCT TO NMRS SHRA/TSRA AND ISOLD +TSRA WILL
PERSIST EAST OF A KPGA-KFGZ LINE 00-05Z...WITH -SHRA TO THE WEST.
STORMS WILL DECREASE FROM THE SOUTHWEST TO NORTHEAST 05Z-10Z. ISOLD
TO SCT SHRA/-TSRA WILL CONTINUE THROUGH 10Z-18Z WED GENERALLY NE OF
A LINE FROM KPGA-KRQE...WITH REDEVELOPMENT OF -TSRA OVR NRN AZ HIGHER
TERRAIN AFTER 18Z WED. AVIATION DISCUSSION NOT UPDATED FOR AMENDMENTS.
&&
.FGZ WATCHES/WARNINGS/ADVISORIES...
FLASH FLOOD WATCH FROM LATE TONIGHT THROUGH TUESDAY EVENING
FOR AZZ004>008-015>018-037-038.
&&
$$
PUBLIC.........BAK
AVIATION.......BAK
FOR NORTHERN ARIZONA WEATHER INFORMATION VISIT
WEATHER.GOV/FLAGSTAFF
AREA FORECAST DISCUSSION
NWS PHOENIX AZ
145 PM MST TUE AUG 26 2014
.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...
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
UNFAVORABLE SOUTHWEST TO WEST STEERING FLOW WILL AFFECT THE CENTRAL
DESERTS THIS AFTERNOON AND OVERNIGHT TONIGHT...AND THE STRONGEST
FORCING WILL REMAIN NORTH OF THE PHOENIX AREA...AFFECTING THE
NORTHERN HALF OF THE STATE. STILL...THERE IS PLENTIFUL MOISTURE
LINGERING ACROSS THE CENTRAL DESERTS AND ISOLATED STORMS MAY DEVELOP
LATER THIS AFTERNOON AND PERSIST INTO THE EVENING HOURS. CONFIDENCE
IS TOO LOW TO MENTION THUNDER IN THE TAFS ATTM...WILL SIMPLY CARRY
SCT-BKN CUMULUS DECKS MAINLY FROM 7-10K FEET. SHOULD STORMS FORM
LATER THIS AFTERNOON THAT MAY AFFECT THE TERMINALS...UPDATES WILL BE
MADE TO THE TAFS. ALSO...SHOULD STORMS DEVELOP GUSTY OUTFLOW WINDS
AND BLOWING DUST MAY EVENTUALLY MOVE IN AND AFFECT THE TERMINALS BUT
AGAIN...CONFIDENCE IS TOO LOW TO MENTION THIS IN THE TAFS AT THIS
TIME. 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...FLASH FLOOD WATCH UNTIL 5 PM THIS AFTERNOON AZZ021>022...AZZ024.
CA...NONE.
&&
$$
VISIT US ON FACEBOOK...TWITTER...AND AT WEATHER.GOV/PHOENIX
DISCUSSION...AJ/MO
AVIATION...CB
FIRE WEATHER...CB
AREA FORECAST DISCUSSION...CORRECTION
NWS PHOENIX AZ
1245 PM MST TUE AUG 26 2014
.UPDATE...UPDATED AVIATION AND FIRE WEATHER DISCUSSIONS.
&&
.SYNOPSIS...
A WEATHER DISTURBANCE WILL PASS NORTH OF THE AREA TODAY HELPING PULL
MOISTURE NORTHWARD AND SUPPORTING INCREASED CHANCES FOR
THUNDERSTORMS. SOMEWHAT MORE WIDESPREAD RAINFALL COVERAGE IS LIKELY
TODAY COMPARED TO YESTERDAY...HOWEVER SOME LOCATIONS MAY MISS OUT ON
RAINFALL ALTOGETHER. STORMS THAT ARE MORE PERSISTENT WILL BE CAPABLE
OF PRODUCING VERY HEAVY RAINFALL. MUCH DRIER AND TRANQUIL WARM
WEATHER ARE ANTICIPATED FOR THE LATTER HALF OF THE WEEK.
&&
.DISCUSSION...
UPPER LOW CURRENTLY CENTERED OVER NEVADA HAS A VORT LOBE SWINGING
AROUND THE BOTTOM OF THE TROUGH OVER THE MOHAVE DESERT. THIS
FEATURE...AND THE ASSOCIATED JET DYNAMICS...HAS GENERATED SCATTERED
SHOWERS AND ISOLATED THUNDERSTORMS OVER JOSHUA TREE NATIONAL PARK
AND PORTIONS OF EASTERN RIVERSIDE COUNTY WITH MOST OF THE ACTIVITY
TO THE NORTH AND NORTHEAST OVER SAN BERNARDINO COUNTY AND MOHAVE
COUNTY. MADE AN UPDATE TO THE FORECAST TO INCREASE POPS OVER EASTERN
RIVERSIDE/JTNP IN RESPONSE TO THE ONGOING SHOWER ACTIVITY AND TO
INCREASE THEM OVER LA PAZ COUNTY AS THE AREA OF FORCING TRANSLATES
EASTWARD. MAIN BRUNT SHOULD STILL BE NORTH OF OUR FORECAST AREA. WE
WILL NEED TO KEEP AN EYE OUT FOR LA PAZ AND NORTHWEST MARICOPA
COUNTY...IN ADDITION TO WHERE WE STILL HAVE THE FLASH FLOOD WATCH.
MAY NEED TO REINSERT THOSE AREAS INTO THE WATCH BUT WILL A BIT
LONGER TO SEE HOW THINGS UNFOLD. LATEST RUC INDICATES A PERSISTENT
BATCH OF FORCING OVER THE PHOENIX AREA THIS AFTERNOON WHICH APPEARS
TO BE ASSOCIATED WITH ANOTHER JET STREAK MOVING ACROSS THE CWA. BUT
12Z NAM AND GFS ARE NOT AS AGGRESSIVE. LOCAL HI RES MODELS FROM 06Z
RUNS KEEP PRECIP OUT OF OUR AREA ALMOST ENTIRELY BUT THEY HAVE NOT
PICKED UP ON THE ACTIVITY IN CALIFORNIA WHICH CALLS THEIR SOLUTIONS
INTO QUESTION. MADE A SUBTLE CHANGE TO PHOENIX AREA FORECAST TO
NUDGE DOWN TO SLIGHT CHANCES FOR THIS MORNING BUT UP TO CHANCE
CATEGORY FOR THIS AFTERNOON. IT IS CONCEIVABLE THAT THE
WATCH...CURRENTLY FOR ZONE 24...MAY NEED TO BE EXTENDED IN TIME. BUT
AGAIN...WILL WAIT A BIT LONGER TO SEE HOW THINGS UNFOLD.
&&
.PREVIOUS DISCUSSION ISSUED 700 AM...
DRY SLOT SUBSIDENCE CONTINUES TO DOMINATE MUCH OF THE FORECAST AREA
THIS MORNING...WITH 2 DISTINCT REGIONS OF ASCENT STRADDLING EITHER
SIDE OF THE CWA. THE MORE PREDOMINANT AREA IS AHEAD OF THE H5 COLD
CORE DESCENDING FROM CNTRL NEVADA...THOUGH THE MOST FAVORABLE AREA
OF LIFT WILL BE FOCUSED IN NORTHERN ARIZONA. A SECONDARY REGION OF
MORE SUBTLE ASCENT WITH A VERY WEAK WAVE OVER SERN ARIZONA MAY FOCUS
LIFT DOWNSTREAM OVER GILA COUNTY. THUS...HAVE CANCELLED THE FLASH
FLOOD WATCH FOR MUCH OF THE AREA...WITH ONLY SOME MODEST EXPECTATION
OF ANY DEVELOPMENT LATER IN THE DAY.
&&
.PREVIOUS DISCUSSION ISSUED 225 AM...
A VERY COMPLEX AND CHAOTIC ATMOSPHERIC STRUCTURE EARLY THIS MORNING
IS RESULTING IN A LOW CONFIDENCE FORECAST DESPITE NUMEROUS
INGREDIENTS PRESENT THAT WOULD SUGGEST AN OTHERWISE ACTIVE
CONVECTIVE PERIOD. FIRST...A WELL DEFINED POSITIVELY TILTED WAVE HAS
DESCENDED INTO CNTRL NEVADA WITH STRONGER JET ENERGY TRANSLATING
INTO THE EASTERN DOWNSTREAM SIDE OF THE WAVE ACROSS NORTHERN
ARIZONA. MEANWHILE...HURRICANE MARIE CONTINUES TO CHURN WELL
SOUTHWEST OF THE BAJA PENINSULA WITH OUTER FEEDER BANDS LOOPING INTO
THE SOUTHERN GULF OF CALIFORNIA. IN BETWEEN THESE TWO FEATURES...A
COL REGION HAS FORMED ALLOWING STRETCHING AND SHEARING OF ANY
SMALLER EASTERLY WAVES PROPAGATING THROUGH NORTHERN MEXICO. THIS COL
REGION IS ALSO NOTABLE FOR ITS STRONGER SUBSIDENCE...AND CURRENT
SATELLITE LOOPS CLEARLY SHOW THIS SUBSIDENT AREA AND DRY SLOT BEING
ADVECTED NORTHEAST INTO CNTRL ARIZONA BEHIND A SHORTWAVE BECOMING
ABSORBED INTO THE NORTHERN ARIZONA JET AXIS.
DESPITE THESE INHIBITING FEATURES...THERE ARE STILL SEVERAL OUTFLOW
BOUNDARIES...GRAVITY WAVES...AND SUBTLE EASTERLY WAVES THAT COULD
INVIGORATE RENEWED CONVECTION LATER THIS MORNING. ONE SUCH FEATURE
OVER SERN ARIZONA WAS ALLOWING PERSISTENT STORMS TO PERCOLATE OVER
GRAHAM COUNTY WITH SOME BACK BUILDING NOTED TOWARDS PIMA COUNTY.
SEVERAL BANDS OF ACCAS ALSO APPEAR EVIDENT THROUGH PARTS OF
PIMA...PINAL...AND MARICOPA COUNTIES...AND SHOULD SUFFICIENT LIFT
PRESENT ITSELF...A MARGINALLY UNSTABLE ENVIRONMENT (MUCAPES UP TO
1000 J/KG) AND JUICY ATMOSPHERE (PWATS NEAR 1.50 INCHES AND LOW
LEVEL MIXING RATIOS APPROACHING 15 G/KG) WOULD SUPPORT STORMS
PRODUCING HEAVY RAIN. HOWEVER...OPERATIONAL AND EXPERIMENTAL HIGH
RESOLUTION MODELS OFFER COMPLETELY MIXED SIGNALS AS TO THE EVOLUTION
OF FEATURES THIS MORNING RANGING FROM A COMPLETE DEARTH OF RAINFALL
TO NUMEROUS STORMS DEVELOPING OVER THE EASTERN CWA AROUND SUNRISE.
HAVE HEDGED THE POP FORECAST TOWARDS SREF MEANS...THOUGH BASED ON
RECENT SATELLITE AND RADAR TRENDS...PROSPECTS DO NOT APPEAR ALL THAT
FAVORABLE.
THE AFOREMENTIONED NEVADA LOW PRESSURE SYSTEM WILL PROPAGATE INTO
WRN UTAH THIS EVENING...WITH STRONGER FORCED JET ASCENT FOCUSED OVER
NORTHERN ARIZONA. TAKING INTO ACCOUNT ALL THE SYNOPTIC FEATURES AND
POTENTIAL MESOSCALE INFLUENCES...MUCH OF THE FORECAST AREA MAY STILL
REMAIN IN AN UNFAVORABLE SUBSIDENT REGION SOUTH OF THE JET AXIS IN
DEEPER SWLY FLOW. THE VAST PREPONDERANCE OF PROBABILISTIC ENSEMBLE
OUTPUT ALONG WITH DETERMINISTIC MODELS PAINT A RATHER DISMAL PICTURE
FOR PRECIPITATION CHANCES OUTSIDE OF HIGHER TERRAIN AREAS OF GILA
COUNTY. CANNOT COMPLETELY DISCOUNT THE ABYSMAL NUMERICAL GUIDANCE
POPS EITHER...AND HAVE ATTEMPTED TO REALLY TRIM POPS FOR LOWER
ELEVATION LOCATIONS THIS AFTERNOON. WILL KEEP THE FLASH FLOOD WATCH
VALID FOR THE TIME BEING GIVEN THE ATMOSPHERIC MOISTURE
PROFILES...THOUGH IF STORMS CANNOT BE GENERATED LOCALLY IT MAY BE
CANCELLED LATER THIS MORNING.
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
UNFAVORABLE SOUTHWEST TO WEST STEERING FLOW WILL AFFECT THE CENTRAL
DESERTS THIS AFTERNOON AND OVERNIGHT TONIGHT...AND THE STRONGEST
FORCING WILL REMAIN NORTH OF THE PHOENIX AREA...AFFECTING THE
NORTHERN HALF OF THE STATE. STILL...THERE IS PLENTIFUL MOISTURE
LINGERING ACROSS THE CENTRAL DESERTS AND ISOLATED STORMS MAY DEVELOP
LATER THIS AFTERNOON AND PERSIST INTO THE EVENING HOURS. CONFIDENCE
IS TOO LOW TO MENTION THUNDER IN THE TAFS ATTM...WILL SIMPLY CARRY
SCT-BKN CUMULUS DECKS MAINLY FROM 7-10K FEET. SHOULD STORMS FORM
LATER THIS AFTERNOON THAT MAY AFFECT THE TERMINALS...UPDATES WILL BE
MADE TO THE TAFS. ALSO...SHOULD STORMS DEVELOP GUSTY OUTFLOW WINDS
AND BLOWING DUST MAY EVENTUALLY MOVE IN AND AFFECT THE TERMINALS BUT
AGAIN...CONFIDENCE IS TOO LOW TO MENTION THIS IN THE TAFS AT THIS
TIME. 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...FLASH FLOOD WATCH UNTIL 5 PM THIS AFTERNOON AZZ021>022...AZZ024.
CA...NONE.
&&
$$
VISIT US ON FACEBOOK...TWITTER...AND AT WEATHER.GOV/PHOENIX
DISCUSSION...AJ
PREVIOUS DISCUSSION...MO
AVIATION...CB
FIRE WEATHER...CB
AREA FORECAST DISCUSSION
NWS PHOENIX AZ
955 AM MST TUE AUG 26 2014
.SYNOPSIS...
A WEATHER DISTURBANCE WILL PASS NORTH OF THE AREA TODAY HELPING PULL
MOISTURE NORTHWARD AND SUPPORTING INCREASED CHANCES FOR
THUNDERSTORMS. SOMEWHAT MORE WIDESPREAD RAINFALL COVERAGE IS LIKELY
TODAY COMPARED TO YESTERDAY...HOWEVER SOME LOCATIONS MAY MISS OUT ON
RAINFALL ALTOGETHER. STORMS THAT ARE MORE PERSISTENT WILL BE CAPABLE
OF PRODUCING VERY HEAVY RAINFALL. MUCH DRIER AND TRANQUIL WARM
WEATHER ARE ANTICIPATED FOR THE LATTER HALF OF THE WEEK.
&&
.DISCUSSION...
UPPER LOW CURRENTLY CENTERED OVER NEVADA HAS A VORT LOBE SWINGING
AROUND THE BOTTOM OF THE TROUGH OVER THE MOHAVE DESERT. THIS
FEATURE...AND THE ASSOCIATED JET DYNAMICS...HAS GENERATED SCATTERED
SHOWERS AND ISOLATED THUNDERSTORMS OVER JOSHUA TREE NATIONAL PARK
AND PORTIONS OF EASTERN RIVERSIDE COUNTY WITH MOST OF THE ACTIVITY
TO THE NORTH AND NORTHEAST OVER SAN BERNARDINO COUNTY AND MOHAVE
COUNTY. MADE AN UPDATE TO THE FORECAST TO INCREASE POPS OVER EASTERN
RIVERSIDE/JTNP IN RESPONSE TO THE ONGOING SHOWER ACTIVITY AND TO
INCREASE THEM OVER LA PAZ COUNTY AS THE AREA OF FORCING TRANSLATES
EASTWARD. MAIN BRUNT SHOULD STILL BE NORTH OF OUR FORECAST AREA. WE
WILL NEED TO KEEP AN EYE OUT FOR LA PAZ AND NORTHWEST MARICOPA
COUNTY...IN ADDITION TO WHERE WE STILL HAVE THE FLASH FLOOD WATCH.
MAY NEED TO REINSERT THOSE AREAS INTO THE WATCH BUT WILL A BIT
LONGER TO SEE HOW THINGS UNFOLD. LATEST RUC INDICATES A PERSISTENT
BATCH OF FORCING OVER THE PHOENIX AREA THIS AFTERNOON WHICH APPEARS
TO BE ASSOCIATED WITH ANOTHER JET STREAK MOVING ACROSS THE CWA. BUT
12Z NAM AND GFS ARE NOT AS AGGRESSIVE. LOCAL HI RES MODELS FROM 06Z
RUNS KEEP PRECIP OUT OF OUR AREA ALMOST ENTIRELY BUT THEY HAVE NOT
PICKED UP ON THE ACTIVITY IN CALIFORNIA WHICH CALLS THEIR SOLUTIONS
INTO QUESTION. MADE A SUBTLE CHANGE TO PHOENIX AREA FORECAST TO
NUDGE DOWN TO SLIGHT CHANCES FOR THIS MORNING BUT UP TO CHANCE
CATEGORY FOR THIS AFTERNOON. IT IS CONCEIVABLE THAT THE
WATCH...CURRENTLY FOR ZONE 24...MAY NEED TO BE EXTENDED IN TIME. BUT
AGAIN...WILL WAIT A BIT LONGER TO SEE HOW THINGS UNFOLD.
&&
.PREVIOUS DISCUSSION ISSUED 700 AM...
DRY SLOT SUBSIDENCE CONTINUES TO DOMINATE MUCH OF THE FORECAST AREA
THIS MORNING...WITH 2 DISTINCT REGIONS OF ASCENT STRADDLING EITHER
SIDE OF THE CWA. THE MORE PREDOMINANT AREA IS AHEAD OF THE H5 COLD
CORE DESCENDING FROM CNTRL NEVADA...THOUGH THE MOST FAVORABLE AREA
OF LIFT WILL BE FOCUSED IN NORTHERN ARIZONA. A SECONDARY REGION OF
MORE SUBTLE ASCENT WITH A VERY WEAK WAVE OVER SERN ARIZONA MAY FOCUS
LIFT DOWNSTREAM OVER GILA COUNTY. THUS...HAVE CANCELLED THE FLASH
FLOOD WATCH FOR MUCH OF THE AREA...WITH ONLY SOME MODEST EXPECTATION
OF ANY DEVELOPMENT LATER IN THE DAY.
&&
.PREVIOUS DISCUSSION ISSUED 225 AM...
A VERY COMPLEX AND CHAOTIC ATMOSPHERIC STRUCTURE EARLY THIS MORNING
IS RESULTING IN A LOW CONFIDENCE FORECAST DESPITE NUMEROUS
INGREDIENTS PRESENT THAT WOULD SUGGEST AN OTHERWISE ACTIVE
CONVECTIVE PERIOD. FIRST...A WELL DEFINED POSITIVELY TILTED WAVE HAS
DESCENDED INTO CNTRL NEVADA WITH STRONGER JET ENERGY TRANSLATING
INTO THE EASTERN DOWNSTREAM SIDE OF THE WAVE ACROSS NORTHERN
ARIZONA. MEANWHILE...HURRICANE MARIE CONTINUES TO CHURN WELL
SOUTHWEST OF THE BAJA PENINSULA WITH OUTER FEEDER BANDS LOOPING INTO
THE SOUTHERN GULF OF CALIFORNIA. IN BETWEEN THESE TWO FEATURES...A
COL REGION HAS FORMED ALLOWING STRETCHING AND SHEARING OF ANY
SMALLER EASTERLY WAVES PROPAGATING THROUGH NORTHERN MEXICO. THIS COL
REGION IS ALSO NOTABLE FOR ITS STRONGER SUBSIDENCE...AND CURRENT
SATELLITE LOOPS CLEARLY SHOW THIS SUBSIDENT AREA AND DRY SLOT BEING
ADVECTED NORTHEAST INTO CNTRL ARIZONA BEHIND A SHORTWAVE BECOMING
ABSORBED INTO THE NORTHERN ARIZONA JET AXIS.
DESPITE THESE INHIBITING FEATURES...THERE ARE STILL SEVERAL OUTFLOW
BOUNDARIES...GRAVITY WAVES...AND SUBTLE EASTERLY WAVES THAT COULD
INVIGORATE RENEWED CONVECTION LATER THIS MORNING. ONE SUCH FEATURE
OVER SERN ARIZONA WAS ALLOWING PERSISTENT STORMS TO PERCOLATE OVER
GRAHAM COUNTY WITH SOME BACK BUILDING NOTED TOWARDS PIMA COUNTY.
SEVERAL BANDS OF ACCAS ALSO APPEAR EVIDENT THROUGH PARTS OF
PIMA...PINAL...AND MARICOPA COUNTIES...AND SHOULD SUFFICIENT LIFT
PRESENT ITSELF...A MARGINALLY UNSTABLE ENVIRONMENT (MUCAPES UP TO
1000 J/KG) AND JUICY ATMOSPHERE (PWATS NEAR 1.50 INCHES AND LOW
LEVEL MIXING RATIOS APPROACHING 15 G/KG) WOULD SUPPORT STORMS
PRODUCING HEAVY RAIN. HOWEVER...OPERATIONAL AND EXPERIMENTAL HIGH
RESOLUTION MODELS OFFER COMPLETELY MIXED SIGNALS AS TO THE EVOLUTION
OF FEATURES THIS MORNING RANGING FROM A COMPLETE DEARTH OF RAINFALL
TO NUMEROUS STORMS DEVELOPING OVER THE EASTERN CWA AROUND SUNRISE.
HAVE HEDGED THE POP FORECAST TOWARDS SREF MEANS...THOUGH BASED ON
RECENT SATELLITE AND RADAR TRENDS...PROSPECTS DO NOT APPEAR ALL THAT
FAVORABLE.
THE AFOREMENTIONED NEVADA LOW PRESSURE SYSTEM WILL PROPAGATE INTO
WRN UTAH THIS EVENING...WITH STRONGER FORCED JET ASCENT FOCUSED OVER
NORTHERN ARIZONA. TAKING INTO ACCOUNT ALL THE SYNOPTIC FEATURES AND
POTENTIAL MESOSCALE INFLUENCES...MUCH OF THE FORECAST AREA MAY STILL
REMAIN IN AN UNFAVORABLE SUBSIDENT REGION SOUTH OF THE JET AXIS IN
DEEPER SWLY FLOW. THE VAST PREPONDERANCE OF PROBABILISTIC ENSEMBLE
OUTPUT ALONG WITH DETERMINISTIC MODELS PAINT A RATHER DISMAL PICTURE
FOR PRECIPITATION CHANCES OUTSIDE OF HIGHER TERRAIN AREAS OF GILA
COUNTY. CANNOT COMPLETELY DISCOUNT THE ABYSMAL NUMERICAL GUIDANCE
POPS EITHER...AND HAVE ATTEMPTED TO REALLY TRIM POPS FOR LOWER
ELEVATION LOCATIONS THIS AFTERNOON. WILL KEEP THE FLASH FLOOD WATCH
VALID FOR THE TIME BEING GIVEN THE ATMOSPHERIC MOISTURE
PROFILES...THOUGH IF STORMS CANNOT BE GENERATED LOCALLY IT MAY BE
CANCELLED LATER THIS MORNING.
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
VERY LOW CONFIDENCE FORECAST AS THE CURRENT ENVIRONMENT IS
UNFAVORABLE FOR STORM DEVELOPMENT...YET THE AIRMASS IS VERY MOIST
AND MARGINALLY UNSTABLE. HAVE REMOVED VCTS MENTION FOR THE TIME
BEING BASED ON CURRENT TRENDS...THOUGH NOT OUT OF THE QUESTION TO
SEE ISOLD/SCT TSRA AROUND THE TERMINAL SITES LATER THIS MORNING.
WINDS DIRECTIONS MAY ALSO BECOME QUITE VARIABLE THROUGH THE MORNING
HOURS...THOUGH SHOULD GENERALLY FAVOR A SE COMPONENT BEFORE BECOMING
MORE SWLY IN THE AFTERNOON.
SOUTHWEST ARIZONA AND SOUTHEAST CALIFORNIA INCLUDING KIPL AND KBLH...
ONLY PERIODIC HIGH CLOUDS EXPECTED THROUGH WEDNESDAY MORNING WITH
ANY STORMINESS LIKELY REMAINING NORTH OF THE AREA. SFC WINDS SHOULD
RETAIN A SLY COMPONENT AT KBLH...WITH MORE VARIABILITY AT KIPL.
OVERALL...NO AVIATION IMPACTS EXPECTED.
AVIATION DISCUSSION NOT UPDATED FOR AMENDED TAFS.
&&
.FIRE WEATHER...
THURSDAY THROUGH MONDAY...
STRONG HIGH PRESSURE ALOFT AND WESTERLY FLOW IS WILL KEEP MONSOON
MOISTURE WELL REMOVED FROM THE DISTRICT...WITH MOSTLY CLEAR SKIES
THROUGH THE ENTIRE PERIOD. TEMPERATURES WILL REMAIN AT OR SLIGHTLY
ABOVE SEASONAL NORMALS WITH MAINLY LIGHT WINDS...THOUGH SOME
AFTERNOON GUSTS CAN BE EXPECTED NEAR UPSLOPE REGIONS. AFTERNOON
HUMIDITIES WILL FALL INTO THE SINGLE DIGITS AND TEENS ACROSS THE
LOWER DESERTS...WITH SOMEWHAT MORE MOIST CONDITIONS ACROSS THE
HIGHER TERRAIN OF GILA COUNTY. OVERNIGHT RECOVERY WILL GENERALLY BE
GOOD.
&&
.PSR WATCHES/WARNINGS/ADVISORIES...
AZ...FLASH FLOOD WATCH UNTIL 2 PM THIS AFTERNOON AZZ024.
CA...NONE.
&&
$$
VISIT US ON FACEBOOK...TWITTER...AND AT WEATHER.GOV/PHOENIX
DISCUSSION...AJ
PREVIOUS DISCUSSION...MO
AVIATION...MO
FIRE WEATHER...PERCHA/MO
AREA FORECAST DISCUSSION...UPDATED
NWS GRAND JUNCTION CO
337 PM MDT TUE AUG 26 2014
CORRECTED LONG TERM DISCUSSION
.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 18Z TAFS THROUGH 18Z WEDNESDAY NOON)
ISSUED AT 1110 AM MDT TUE AUG 26 2014
SHOWERS AND THUNDERSTORMS WILL REMAIN IN THE FORECAST THROUGH
WEDNESDAY...WITH COVERAGE INCREASING THROUGHOUT THIS AFTERNOON
AND TONIGHT. EXPECT AREAS OF MVFR CIGS TO DEVELOP TONIGHT AS
RAINFALL INCREASES...ESPECIALLY SOUTH OF INTERSTATE 70. HEAVY
RAIN...SMALL HAIL AND GUSTY OUTFLOW WINDS WILL OCCUR NEAR THE
STRONGER STORMS. ALL SITES WILL SEE THE POTENTIAL FOR SHOWERS AND
THUNDERSTORMS EXCEEDING 50 PERCENT THROUGH WEDNESDAY.
&&
.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.
&&
$$
SHORT TERM...TGR
LONG TERM...JOE
AVIATION...JDC/JOE
AREA FORECAST DISCUSSION
NWS GRAND JUNCTION CO
239 PM MDT TUE AUG 26 2014
.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. THURSDAY AFTERNOON. NORTHWESTERLY FLOW
DEVELOPS BEHIND THE TROUGH WHICH WILL KEEP SCATTERED PRECIP ACROSS
THE CO MTNS. DRIER AIR SPREADS ACROSS ERN UT INTO FAR WRN CO THU.
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 18Z TAFS THROUGH 18Z WEDNESDAY NOON)
ISSUED AT 1110 AM MDT TUE AUG 26 2014
SHOWERS AND THUNDERSTORMS WILL REMAIN IN THE FORECAST THROUGH
WEDNESDAY...WITH COVERAGE INCREASING THROUGHOUT THIS AFTERNOON
AND TONIGHT. EXPECT AREAS OF MVFR CIGS TO DEVELOP TONIGHT AS
RAINFALL INCREASES...ESPECIALLY SOUTH OF INTERSTATE 70. HEAVY
RAIN...SMALL HAIL AND GUSTY OUTFLOW WINDS WILL OCCUR NEAR THE
STRONGER STORMS. ALL SITES WILL SEE THE POTENTIAL FOR SHOWERS AND
THUNDERSTORMS EXCEEDING 50 PERCENT THROUGH WEDNESDAY.
&&
.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.
&&
$$
SHORT TERM...TGR
LONG TERM...JOE
AVIATION...JDC/JOE
AREA FORECAST DISCUSSION
NWS GRAND JUNCTION CO
1200 PM MDT TUE AUG 26 2014
.UPDATE...
ISSUED AT 1152 AM MDT TUE AUG 26 2014
AFTER COLLABORATION WITH SLC...THINK IT BEST TO GO WITH FLASH
FLOOD WATCH FOR SERN UT THROUGH MIDNIGHT TONIGHT. LATEST RADAR
RETURNS SHOW MORE CELLS STARTING TO FIRE OVER WATCH AREA AND
EXPECTING THIS TREND TO CONTINUE. THUNDERSTORMS AND SHOWERS WILL
ALSO BECOME MORE INTENSE AS THE DAY PROGRESSES WITH HEAVY RAIN
LIKELY UNDER THE STRONGEST STORMS.
UPDATE ISSUED AT 1121 AM MDT TUE AUG 26 2014
A LINE OF SHOWERS AND STORMS STRETCHES FROM STEAMBOAT SPRINGS SW
DOWN TO THE GRAND VALLEY AND THEN CANYONLANDS IN RESPONSE TO UPPER
LEVEL DIVERGENCE AND JET STREAK ALOFT. MODELS NOT INTIALIZING TOO
WELL THIS MORNING WITH EXCEPTION OF HRRR THAT IS PICKING UP ON
SOME FEATURES ESPECIALLY PRECIP OVER NM AND AZ. IF HRRR PULLS
THROUGH...PRECIP WILL INCREASE TOWARDS THE EVENING HOURS OVER SE UT
BEFORE OVERSPREADING THE REST OF THE CWA OVERNIGHT. IN CONTRAST...NAM12
SHOWS COVERAGE INCREASING FROM NOON ONWARDS WITH HIGHER TERRAIN
FAVORED AS SHORTWAVE MOVES THROUGH. SOME CONCERNS THIS MORNING ARE
CLOUD COVER WHICH MAY INHIBIT CONVECTION THOUGH BREAKS IN CLOUDS
ARE OCCURRING OVER SWRN CO WHICH SHOULD ALLOW CONVECTION TO FIRE
AS THE DAY PROGRESSES. OTHER CONCERN IS IF PRECIP BECOMES MORE
STRATIFORM IN NATURE LOWERING FLASH FLOODING CHANCES. CONFIDENCE
NOT THAT GREAT IN ANY MODEL SOLN SO WILL CONTINUE TO MONITOR
EVOLUTION OF LOW PRESSURE AND ACCOMPANYING PRECIP AND FLASH FLOOD
CHANCES.
&&
.SHORT TERM...(TODAY THROUGH WEDNESDAY)
ISSUED AT 346 AM MDT TUE AUG 26 2014
TRANSITION DAY TODAY AS WE START TO SEE THE INFLUENCE OF STRONG
FALL LIKE SYSTEM DIGGING INTO THE GREAT BASIN. MOISTURE WRAPPING
AROUND THE SOUTHERN AND EASTERN FLANKS OF THE STRENGTHENING LOW
PRESSURE SYSTEM WILL BRING WIDESPREAD SHOWERS AND THUNDERSTORMS TO
MUCH OF WESTERN COLORADO AND EASTERN UTAH OVER THE NEXT FEW DAYS.
MODELS HAVE BACKED OFF A BIT ON POTENTIAL QPF VALUES THIS
AFTERNOON...BUT INCREASING DYNAMICS ASSOCIATED WITH THE
APPROACHING LOW AND AVAILABLE MOISTURE CLIMBING BACK TO AN INCH
ACROSS THE FOUR CORNERS WILL RESULT IN LOCALLY HEAVY RAINFALL BY
LATE THIS AFTERNOON...MAINLY OVER THE SAN JUANS AND ADJACENT
SOUTHERN VALLEYS. FOUR CORNERS REGION BEING HIGHLIGHT BY WPC FOR
EXCESSIVE RAINFALL OVER THE NEXT 24 TO 36 HOURS AND CURRENT FLASH
FLOOD WATCH REMAINS ON TRACK. BULK OF HEAVIER RAIN WILL BE HOLDING
OFF UNTIL LATE IN THE DAY BASED ON LATEST 06Z MODELS...SO HAVE
TWEAKED DAYTIME POPS AND QPF DOWN A BIT AND NUDGED OVERNIGHT
VALUES UP A BIT. HAVE ALSO EXTENDED THE FLASH FLOOD WATCH THROUGH
9 AM WEDNESDAY MORNING AS BEST FORCING ASSOCIATED WITH THE LOW
MOVING IN OVERNIGHT. TEMPS WILL BE DOWN A FEW DEGREES TODAY WITH
INCREASED CLOUD COVER AND LOW LEVEL MOISTURE.
THE UPPER LOW SWINGS INTO WRN UT THIS EVENING. SHOWERS AND SCATTERED
THUNDERSTORMS CONTINUE IN DIFLUENT FLOW AHEAD OF THE LOW.
INSTABILITY NOT GREAT PER MODEL LIFTED INDEX AND CAPE...BUT MOISTURE
IS AMPLE ESPECIALLY ACROSS THE SOUTH WHERE LIFT SHOULD BE AIDED BY
SOUTHERLY UPSLOPE FLOW INTO THE SAN JUANS.
THE UPPER LOW CENTER IS FORECAST TO BE OVER NE UT BY NOON WED AND
ACROSS WRN CO WED EVENING. LARGE-SCALE ASCENT ASSOCIATED WITH THE
LOW CENTER PLUS LOWER LEVEL MOISTURE CONVERGENCE AS THE MOISTURE
STREAM WRAPS INTO THE LOW WILL KEEP RAIN/RAIN SHOWERS WITH EMBEDDED
THUNDERSTORMS A DECENT BET FOR MUCH OF THE CENTRAL AND NORTH WED.
UPPER JET CUTS ACROSS THE 4 CORNERS BY MIDDAY ENTRAINING SOMEWHAT
DRIER AIR ALOFT. RAIN COVERAGE LOOKS LESS ACROSS THE SOUTH BUT
STORMS COULD BE STRONGER WITH MODEST CAPE/INSTABILITY...SOME DRYING
ALOFT AND BETTER VERTICAL SHEAR WITH THE JET PASSING. NUDGED THE WED
POPS UPWARD TONIGHT AND WED. TEMPS REMAIN ON THE COOL SIDE OF
NORMAL.
.LONG TERM...(WEDNESDAY NIGHT THROUGH MONDAY)
ISSUED AT 346 AM MDT TUE AUG 26 2014
THE UPPER TROUGH MOVES INTO ERN UT BY THURSDAY AFTERNOON.
NORTHWESTERLY FLOW DEVELOPS BEHIND THE TROUGH WHICH WILL KEEP
SCATTERED PRECIP ACROSS THE CO MTNS. DRIER AIR SPREADS ACROSS ERN UT
INTO FAR WRN CO THU.
FLAT RIDGING FRIDAY GIVES WAY TO BRIEF PERIOD OF ZONAL FLOW
SATURDAY AND EARLY SUNDAY...BEFORE HEIGHTS DROP ONCE AGAIN AS
ANOTHER PACIFIC SYSTEM SLIDES ACROSS WYOMING. THIS WAVE CLIPS THE
NORTHERN HALF OF THE FORECAST AREA...BRINGING A CHANCE FOR SHOWERS
AND THUNDERSTORMS LATE SUNDAY AND SUNDAY NIGHT WITH A FEW SHOWERS
LINGERING INTO THE DAY ON MONDAY. TEMPS WILL MODERATE A BIT FRIDAY
AND SATURDAY...BEFORE DROPPING BACK BELOW SEASONAL NORMS AS WE
MOVE INTO THE NEW WORK WEEK.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY NOON)
ISSUED AT 1110 AM MDT TUE AUG 26 2014
SHOWERS AND THUNDERSTORMS WILL REMAIN IN THE FORECAST THROUGH
WEDNESDAY...WITH COVERAGE INCREASING THROUGHOUT THIS AFTERNOON
AND TONIGHT. EXPECT AREAS OF MVFR CIGS TO DEVELOP TONIGHT AS
RAINFALL INCREASES...ESPECIALLY SOUTH OF INTERSTATE 70. HEAVY
RAIN...SMALL HAIL AND GUSTY OUTFLOW WINDS WILL OCCUR NEAR THE
STRONGER STORMS. ALL SITES WILL SEE THE POTENTIAL FOR SHOWERS AND
THUNDERSTORMS EXCEEDING 50 PERCENT THROUGH WEDNESDAY.
&&
.GJT WATCHES/WARNINGS/ADVISORIES...
CO...FLASH FLOOD WATCH THROUGH WEDNESDAY MORNING FOR COZ018-019-
021>023.
UT...FLASH FLOOD WATCH THROUGH THIS EVENING FOR UTZ022-027-029.
&&
$$
UPDATE...TGR
SHORT TERM...JDC/JAD
LONG TERM...JAD/JDC
AVIATION...JDC/JOE
AREA FORECAST DISCUSSION
NWS GRAND JUNCTION CO
1131 AM MDT TUE AUG 26 2014
.UPDATE...
ISSUED AT 1121 AM MDT TUE AUG 26 2014
A LINE OF SHOWERS AND STORMS STRETCHES FROM STEAMBOAT SPRINGS SW
DOWN TO THE GRAND VALLEY AND THEN CANYONLANDS IN RESPONSE TO UPPER
LEVEL DIVERGENCE AND JET STREAK ALOFT. MODELS NOT INTIALIZING TOO
WELL THIS MORNING WITH EXCEPTION OF HRRR THAT IS PICKING UP ON
SOME FEATURES ESPECIALLY PRECIP OVER NM AND AZ. IF HRRR PULLS
THROUGH...PRECIP WILL INCREASE TOWARDS THE EVENING HOURS OVER SE UT
BEFORE OVERSPREADING THE REST OF THE CWA OVERNIGHT. IN CONTRAST...NAM12
SHOWS COVERAGE INCREASING FROM NOON ONWARDS WITH HIGHER TERRAIN
FAVORED AS SHORTWAVE MOVES THROUGH. SOME CONCERNS THIS MORNING ARE
CLOUD COVER WHICH MAY INHIBIT CONVECTION THOUGH BREAKS IN CLOUDS
ARE OCCURRING OVER SWRN CO WHICH SHOULD ALLOW CONVECTION TO FIRE
AS THE DAY PROGRESSES. OTHER CONCERN IS IF PRECIP BECOMES MORE
STRATIFORM IN NATURE LOWERING FLASH FLOODING CHANCES. CONFIDENCE
NOT THAT GREAT IN ANY MODEL SOLN SO WILL CONTINUE TO MONITOR
EVOLUTION OF LOW PRESSURE AND ACCOMPANYING PRECIP AND FLASH FLOOD
CHANCES.
&&
.SHORT TERM...(TODAY THROUGH WEDNESDAY)
ISSUED AT 346 AM MDT TUE AUG 26 2014
TRANSITION DAY TODAY AS WE START TO SEE THE INFLUENCE OF STRONG
FALL LIKE SYSTEM DIGGING INTO THE GREAT BASIN. MOISTURE WRAPPING
AROUND THE SOUTHERN AND EASTERN FLANKS OF THE STRENGTHENING LOW
PRESSURE SYSTEM WILL BRING WIDESPREAD SHOWERS AND THUNDERSTORMS TO
MUCH OF WESTERN COLORADO AND EASTERN UTAH OVER THE NEXT FEW DAYS.
MODELS HAVE BACKED OFF A BIT ON POTENTIAL QPF VALUES THIS
AFTERNOON...BUT INCREASING DYNAMICS ASSOCIATED WITH THE
APPROACHING LOW AND AVAILABLE MOISTURE CLIMBING BACK TO AN INCH
ACROSS THE FOUR CORNERS WILL RESULT IN LOCALLY HEAVY RAINFALL BY
LATE THIS AFTERNOON...MAINLY OVER THE SAN JUANS AND ADJACENT
SOUTHERN VALLEYS. FOUR CORNERS REGION BEING HIGHLIGHT BY WPC FOR
EXCESSIVE RAINFALL OVER THE NEXT 24 TO 36 HOURS AND CURRENT FLASH
FLOOD WATCH REMAINS ON TRACK. BULK OF HEAVIER RAIN WILL BE HOLDING
OFF UNTIL LATE IN THE DAY BASED ON LATEST 06Z MODELS...SO HAVE
TWEAKED DAYTIME POPS AND QPF DOWN A BIT AND NUDGED OVERNIGHT
VALUES UP A BIT. HAVE ALSO EXTENDED THE FLASH FLOOD WATCH THROUGH
9 AM WEDNESDAY MORNING AS BEST FORCING ASSOCIATED WITH THE LOW
MOVING IN OVERNIGHT. TEMPS WILL BE DOWN A FEW DEGREES TODAY WITH
INCREASED CLOUD COVER AND LOW LEVEL MOISTURE.
THE UPPER LOW SWINGS INTO WRN UT THIS EVENING. SHOWERS AND SCATTERED
THUNDERSTORMS CONTINUE IN DIFLUENT FLOW AHEAD OF THE LOW.
INSTABILITY NOT GREAT PER MODEL LIFTED INDEX AND CAPE...BUT MOISTURE
IS AMPLE ESPECIALLY ACROSS THE SOUTH WHERE LIFT SHOULD BE AIDED BY
SOUTHERLY UPSLOPE FLOW INTO THE SAN JUANS.
THE UPPER LOW CENTER IS FORECAST TO BE OVER NE UT BY NOON WED AND
ACROSS WRN CO WED EVENING. LARGE-SCALE ASCENT ASSOCIATED WITH THE
LOW CENTER PLUS LOWER LEVEL MOISTURE CONVERGENCE AS THE MOISTURE
STREAM WRAPS INTO THE LOW WILL KEEP RAIN/RAIN SHOWERS WITH EMBEDDED
THUNDERSTORMS A DECENT BET FOR MUCH OF THE CENTRAL AND NORTH WED.
UPPER JET CUTS ACROSS THE 4 CORNERS BY MIDDAY ENTRAINING SOMEWHAT
DRIER AIR ALOFT. RAIN COVERAGE LOOKS LESS ACROSS THE SOUTH BUT
STORMS COULD BE STRONGER WITH MODEST CAPE/INSTABILITY...SOME DRYING
ALOFT AND BETTER VERTICAL SHEAR WITH THE JET PASSING. NUDGED THE WED
POPS UPWARD TONIGHT AND WED. TEMPS REMAIN ON THE COOL SIDE OF
NORMAL.
.LONG TERM...(WEDNESDAY NIGHT THROUGH MONDAY)
ISSUED AT 346 AM MDT TUE AUG 26 2014
THE UPPER TROUGH MOVES INTO ERN UT BY THURSDAY AFTERNOON.
NORTHWESTERLY FLOW DEVELOPS BEHIND THE TROUGH WHICH WILL KEEP
SCATTERED PRECIP ACROSS THE CO MTNS. DRIER AIR SPREADS ACROSS ERN UT
INTO FAR WRN CO THU.
FLAT RIDGING FRIDAY GIVES WAY TO BRIEF PERIOD OF ZONAL FLOW
SATURDAY AND EARLY SUNDAY...BEFORE HEIGHTS DROP ONCE AGAIN AS
ANOTHER PACIFIC SYSTEM SLIDES ACROSS WYOMING. THIS WAVE CLIPS THE
NORTHERN HALF OF THE FORECAST AREA...BRINGING A CHANCE FOR SHOWERS
AND THUNDERSTORMS LATE SUNDAY AND SUNDAY NIGHT WITH A FEW SHOWERS
LINGERING INTO THE DAY ON MONDAY. TEMPS WILL MODERATE A BIT FRIDAY
AND SATURDAY...BEFORE DROPPING BACK BELOW SEASONAL NORMS AS WE
MOVE INTO THE NEW WORK WEEK.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY NOON)
ISSUED AT 1110 AM MDT TUE AUG 26 2014
SHOWERS AND THUNDERSTORMS WILL REMAIN IN THE FORECAST THROUGH
WEDNESDAY...WITH COVERAGE INCREASING THROUGHOUT THIS AFTERNOON
AND TONIGHT. EXPECT AREAS OF MVFR CIGS TO DEVELOP TONIGHT AS
RAINFALL INCREASES...ESPECIALLY SOUTH OF INTERSTATE 70. HEAVY
RAIN...SMALL HAIL AND GUSTY OUTFLOW WINDS WILL OCCUR NEAR THE
STRONGER STORMS. ALL SITES WILL SEE THE POTENTIAL FOR SHOWERS AND
THUNDERSTORMS EXCEEDING 50 PERCENT THROUGH WEDNESDAY.
&&
.GJT WATCHES/WARNINGS/ADVISORIES...
CO...FLASH FLOOD WATCH THROUGH WEDNESDAY MORNING FOR COZ018-019-
021>023.
UT...NONE.
&&
$$
UPDATE...TGR
SHORT TERM...JDC/JAD
LONG TERM...JAD/JDC
AVIATION...JDC/JOE
AREA FORECAST DISCUSSION
NWS TOPEKA KS
1228 PM CDT Tue Aug 26 2014
...Update to aviation forecast discussion...
.SHORT TERM...(Today and Tonight)
Issued at 401 AM CDT TUE AUG 26 2014
Early this morning a broad mid-level ridge remained anchored over
the southeastern quadrant of the U.S. with a deepening mid-level
trough over the Great Basin area. With this pattern in place,
southwesterly flow aloft prevailed across the central U.S. with
water vapor imagery showing a few weak embedded shortwaves
developing across Kansas and Nebraska early this morning. At the
surface, low pressure was in place with a fairly stationary boundary
across south central Kansas and extending into northeast Kansas,
essentially bisecting the forecast area. With the support of a
stronger embedded shortwave, an MCS quickly developed across eastern
Nebraska early this morning and persisted through the overnight
hours as it was supported by the low-level jet and decent isentropic
lift. A weaker shortwave was noted across central Kansas, which
sparked a cluster of showers and thunderstorms overnight. However,
this activity was gradually weakening as outflow boundaries
continued to gust out ahead of the storms. As a result, local radar
showed several outflow boundaries situated across the region from
this activity. Mid-level clouds were in place over eastern Kansas,
providing better insolation and keeping temperatures more mild in
the mid/upper 70s. However, cooler conditions were noted over north
central Kansas as a result of the rain-cooled air, bringing
temperatures down into the mid 60s to low 70s.
The precipitation forecast continues to be a challenge in the short
term as we continue to deal with a stationary boundary over the
forecast area, passing weak embedded shortwaves, and lingering
outflow boundaries from overnight convection. The HRRR has been
handling the morning activity fairly well and shows the
precipitation lifting northward and becoming more focused near the
Kansas/Nebraska border before finally diminishing by mid to late
morning. However, there is uncertainty with whether or not any
additional convection will develop near the stationary boundary
and/or along any of the lingering outflow boundaries this afternoon. While a
few models are hinting at this redevelopment, they vary with regards
to the location of the precipitation. At this time, have increasing
PoPs during the afternoon hours into this evening across the
northern half of the forecast area. A stronger embedded shortwave
may once again track across north central Kansas into Nebraska late
tonight, supporting overnight convection primarily near the
Kansas/Nebraska border. While the potential for severe weather is
low, cannot rule out some strong wind gusts and locally heavy rain.
With this set-up in place, temperatures are also a challenge for
today as they will be greatly affected by any precipitation that
develops. In general, expect slightly cooler conditions across far
northern Kansas where precipitation may linger this morning and
potentially redevelop this afternoon. However, conditions may still
heat up across east central Kansas as this region may stay mostly
dry through the day. Afternoon highs in this area could reach into
the mid/upper 90s with heat indices reaching into the 100 to 103
degree range. This area may be close to heat advisory criteria, but
due to the uncertainty in the development of any afternoon
convection, have not issued one at this time but will need to
closely monitor through the day. Low temperatures tonight are
expected to drop into the upper 60s north to low 70s south.
.LONG TERM...(Wednesday through Monday)
Issued at 401 AM CDT TUE AUG 26 2014
Wednesday will likely see an ongoing MCS across Nebraska as models
focus on areas north of the Kansas border. Expect outflow boundaries
to be present across the northern CWA and possibly some ongoing
convection through the morning hours. Left over boundaries may also
be a focus for additional development in the afternoon as well.
Wednesday night into Thursday energy will eject out of the Rockies
trough across western Kansas and Nebraska this along with the low
level jet should fuel yet another MCS across the Plains mainly
across Nebraska. Western Kansas convection will move east into the
CWA Wednesday night and into Thursday morning. Additionally Nebraska
MCS could also clip the northern counties and have maintained
highest probabilities of showers and thunderstorms to the north of
I-70.
The models slowly move the upper trough across the Rockies and
Plains as it is cut off from the westerlies. The 00Z GFS and the 00Z
ECMWF continue to be in agreement with the speed of the trough
through the end of the week while the GFS ensemble mean is just a
tad faster as is the GEM with the passage of the trough axis across
eastern Kansas and western Missouri. Front should move into central
Kansas Thursday night into Friday then progress slowly across
eastern Kansas through Saturday. The front will be a focus for
convection as well as locally heavy rainfall as precipitable water
values of 1.50 to 2.00 inches will be in place. Good moisture
transport will continue each night across the plains as the low
level jet increases and larger scale ascent increases with the
approach of the upper trough. Some convection may linger into Sunday
in the east with another chance of thunderstorms late Sunday night
and into Monday as a wave moves through the Zonal flow across the
Central Plains. Temperatures will gradually cool by the end of the
week with Wednesday being the warmest day especially south of I-70.
Near normal temperatures in the upper 80s to lower 90s are expected
from Thursday through Monday.
&&
.AVIATION...(For the 18Z TAFs through 18Z Wednesday Afternoon)
Issued at 1227 PM CDT TUE AUG 26 2014
VFR conditions are expected throughout the period, with easterly winds
becoming more southerly overnight. There is a possibility of thunderstorms
this evening/tonight, but right now location and even actual
occurrence is uncertain so they have been left out of this TAF
package.
&&
.TOP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...Hennecke
LONG TERM...53
AVIATION...Barjenbruch/Heller
AREA FORECAST DISCUSSION
NWS LOUISVILLE KY
105 PM EDT Tue Aug 26 2014
...Updated Aviation Discussion...
...Forecast Update...
Issued at 1125 AM EDT Tue Aug 26 2014
Forecast is largely on track this morning, although did make an
update to add some isolated showers or a storm west of the I-65
corridor. Current analysis shows dew points starting to pool in this
area on the western edge of the surface high. SPC mesoanalysis
moisture convergence parameter also confirms this. Additionally,
have support from the HRRR that isolated to widely scattered
showers/storms should pop up by early afternoon.
Forecast soundings indicate at least moderately strong instability
will be available this afternoon due to the very moist low levels
combined with steep low level lapse rates. Deep layer flow is quite
weak, so only expect localized gusty winds in the vicinity of
showers/storms and some brief heavy rainfall.
.SHORT TERM (Now through Wednesday)...
Issued at 317 AM EDT Tue Aug 26 2014
Morning IR satellite and surface observations reveal mostly clear
skies across southern Indiana and central Kentucky. Some patchy fog
has developed in the typical fog prone areas and in areas that
picked up a bit of rainfall Monday afternoon. Temperatures remained
quite mild with readings in the lower-middle 70s. Expect quiet
weather to continue through the remainder of the overnight hours
with overnight minimums dropping only a few more degrees or so.
For Today/Tonight, the short term multi-model consensus continues to
be in agreement with increasing the strength of the mid-level ridge
axis overhead. This should result in another mostly sunny and muggy
day across the region. With some additional mid-level warming and
slight drying of the column, current thinking is that convection
will be a bit more isolated. However, high resolution convective
allowing models suggest that storms will fire up to our north along
the periphery of the ridge axis. These could slide southward in the
afternoon and affect our far northern areas of southern Indiana.
Thus, have maintained an isolated storm chance up that way for the
late afternoon hours. Afternoon highs will be similar to Monday
with readings in the upper 80s to the lower 90s. Skies are expected
to clear back out tonight as any convection dissipates after
sunset. Overnight lows will cool into the upper 60s in the far NE
to the lower 70s in the central and southwest.
For Wednesday, the upper level ridge axis is expected to shift a bit
further to the south along with the surface ridge axis. This will
allow a surface frontal boundary to sag southward through central
Indiana. Convection is expected to develop during the afternoon
hours along this front and this activity may eventually spread
southward into southern Indiana and the northern half of KY. For
now, isolated-scattered PoPs still look like a good bet at this
time. Afternoon highs will be warm once again with readings topping
out in the upper 80s in the north with lower 90s in the south.
.LONG TERM (Wednesday Night through Monday)...
Issued at 307 AM EDT Tue Aug 26 2014
Ridging across the southeastern United States will slowly shift
eastward through the long term. As it does so a shortwave trough
will approach from the west, moving across the upper Midwest Sunday
and across the Great Lakes region by Monday morning. At the surface
a weak frontal boundary near the KY/TN border at the beginning of
the period will eventually push back northward as a warm front
Friday.
For Wednesday night a few residual showers or storms may be ongoing
at the start of the period. However, these should dissipate
overnight with mostly dry conditions expected. Diurnal storms are
expected once again on Thursday and Friday, particularly in the
vicinity of the frontal boundaries. The better chance will be on
Thursday with scattered storms across the region. Friday`s storms
look to be more isolated in nature.
Rain chances will increase through the weekend as the upper level
trough nears and its associated surface low lifts north of the
region. The best chances for storms this weekend looks to be on
Sunday as precipitable water values rise to around 1.9 inches and we
become moderately unstable. Will keep chances in the 40-50% range
right now considering there is still some differences in the
development of the system between the model solutions. Monday will
see a return to the more summertime diurnal pattern of storms before
a cold front approaches towards midweek.
Temperatures will be in the upper 80s to lower 90s through Saturday
with lows in the upper 60s to lower 70s. With rain and clouds
expected Sunday into Monday we should see a bit of a cool down,
particularly on Sunday with highs in the lower to mid 80s expected.
This will not last however, as a return to upper 80s is expected by
Tuesday.
&&
.AVIATION (18Z TAF Update)...
Issued at 105 PM EDT Tue Aug 26 2014
A few showers have popped up around the BWG terminal early this
afternoon where the best low level moisture convergence is occurring
on the western edge of the surface high. Have included VCSH mention
at BWG through sundown. SDF would be the other site that could
experience a shower or two this afternoon/evening, however coverage
is less certain in this area so will leave dry for now. Expect
generally light and variable winds today with any noticeable
gradient out of the ENE. Expect only Sct Cu around 4 k feet.
Some fog will be possible at the TAF sites again toward dawn, with
light and variable winds and scattered clouds around 4 k feet once
again on Wednesday. Some showers may settle across SDF/BWG tomorrow
afternoon ahead of a frontal boundary.
&&
.LMK WATCHES/WARNINGS/ADVISORIES...
KY...NONE.
IN...NONE.
&&
$$
Update.........BJS
Short Term.....MJ
Long Term......EER
Aviation.......BJS
AREA FORECAST DISCUSSION
NWS SHREVEPORT LA
255 PM CDT TUE AUG 26 2014
.DISCUSSION...
ISOLD SHWRS/TSTMS NOTED ON KSHV RADAR THIS AFTN. WHILE THE TUTT
CONTINUES TO STIR UP SLIGHTLY MORE ORGANIZED CONVECTION ACROSS THE
NRN GULF COAST...IT IS HAVING DECIDEDLY LESS INFLUENCE ACROSS OUR
REGION TODAY VERSUS MONDAY. AT ANY RATE...THE WEAKNESS IN THE
UPPER RIDGE IS MAKING FOR COOLER TEMPS TODAY.
A DRIER AIRMASS IS EXPECTED TO MOVE INTO THE REGION OVERNIGHT...
WHICH WILL ALLOW FOR VERY EFFECTIVE MIXING DURING WEDNESDAY AFTN.
WHILE TEMPS ARE EXPECTED TO WARM INTO THE MID 90S...DEW POINTS AS
LOW AS 60 DEGREES WILL BE POSSIBLE...WHICH WILL KEEP OUR HEAT
INDEX VALUES BELOW 100 DEGREES FOR THE FIRST TIME IN SEVERAL DAYS.
CHANCES FOR ISOLD CONVECTION WILL PICK BACK UP THURSDAY...AS THE
UPPER RIDGE BEGINS TO BE FORCED EWD BY AN APPROACHING TROF. MODELS
IN GOOD AGREEMENT FOR AN INCREASE IN RAIN CHANCES INTO FRIDAY AND
SATURDAY...AS THE TROF BEGINS TO MOVE ACROSS THE PLAINS AND INTO
THE MS RIVER VALLEY. WHILE THE UPPER TROF IS FCST TO DAMPEN/MOVE
EWD SUNDAY INTO EARLY NEXT WEEK...SLIGHTLY ENHANCED RAIN CHANCES
ARE EXPECTED TO LINGER IN THE ABSENCE OF THE UPPER RIDGE...WHICH
WILL CONTINUE TO HANG OUT OVER THE E COAST OF THE U.S. AS A RESULT
OF CONVECTION/CLOUD COVER...TEMPS WILL RUN NEAR OR EVEN SLIGHTLY
BELOW NORMAL THROUGH THE EXTENDED. /12/
&&
AVIATION... LATEST VIS IMAGERY THIS MORNING SHOWS OUR INVERTED
TROUGH OR TUTT LOW ACROSS THE S LA COAST...NOT LOOKING NEARLY AS
DEFINED AS WAS THE CASE THIS TIME ON MONDAY. 12Z NAM OUTPUT NOT
NEARLY AS SUPPORTIVE OF PRECIP COVERAGE TODAY COMPARED TO PREVIOUS
RUNS. HAVING SAID THAT...LATEST HRRR STILL SUGGESTS ISOLATED
CONVECTION DEVELOPING BY EARLY AFTERNOON ACROSS PORTIONS OF THE
REGION BUT THE KEY WORD IS ISOLATED.
FOR THE 18Z TAF PACKAGE...WILL NOT MAKE MENTION OF VCSH/VCTS AS
COVERAGE WILL JUST BE TOO SPARSE. CU FIELD SHOULD DEVELOP OVER THE
NEXT COUPLE HOURS WITH HEIGHTS RANGING FROM 4-6KFT THROUGH THE
AFTERNOON. CU FIELD SHOULD QUICKLY DISSIPATE AFTER SUNSET.
KEPT MENTION OF PATCHY FOG IN AT THE MLU TERMINAL OVERNIGHT BUT
MUCH DRIER AIR FILTERING IN FROM THE EAST MAY DETOUR THAT FROM
OCCURRING. /13/
&&
.PRELIMINARY POINT TEMPS/POPS...
SHV 72 95 74 94 76 / 10 10 10 20 20
MLU 69 94 71 93 73 / 10 10 10 20 20
DEQ 71 93 69 91 71 / 10 10 10 20 20
TXK 72 93 70 92 73 / 10 10 10 20 20
ELD 69 93 68 91 71 / 10 10 10 20 20
TYR 73 96 75 95 76 / 10 10 10 20 20
GGG 71 96 73 94 74 / 10 10 10 20 20
LFK 74 96 75 95 76 / 10 20 10 30 20
&&
.SHV WATCHES/WARNINGS/ADVISORIES...
AR...NONE.
LA...NONE.
OK...NONE.
TX...NONE.
&&
$$
12
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
126 PM EDT TUE AUG 26 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 501 AM EDT TUE AUG 26 2014
PER WATER VAPOR IMAGERY AND RUC ANALYSIS...VIGOROUS SHORTWAVE THAT
WAS MOVING INTO SRN MANITOBA 24HRS AGO IS NOW MUCH WEAKER AND
TRACKING THRU NRN ONTARIO. ASSOCIATED COLD FRONT SWEPT ACROSS UPPER
MI DURING THE NIGHT...USHERING IN MUCH DRIER AIR. SFC DWPTS THAT
WERE IN THE 60S TO AROUND 70F ARE NOW DOWN IN THE MORE COMFORTABLE
50S AT NEARLY ALL LOCATIONS. UPSTREAM...QUITE A BIT OF CLOUD COVER IS
NOTED ACROSS THE NRN HALF OF MN...AND THERE HAVE EVEN BEEN A FEW
-SHRA/SPRINKLES IN NE MN. IN THE LAST FEW HRS...THE CLOUDS HAVE BEEN
THINNING OUT...AND RECENTLY THE CLOUDS HAVE SPREAD INTO WRN UPPER
MI. THESE CLOUDS ARE SITUATED IN THE 850MB THERMAL TROF WHICH HAS
850MB TEMPS AS LOW AS 4-5C OVER FAR NRN MN.
TODAY...850MB TROF SHIFTS INTO THE UPPER GREAT LAKES. WITH ONSET OF
DAYTIME HEATING COINCIDING WITH ARRIVAL OF THERMAL TROF...THERE
SHOULD BE AN EXPANSION OF SCT/BKN CU/STRATOCU FOR A TIME...
ESPECIALLY ACROSS THE N. DURING THE MID AND LATE AFTN...THE CLOUDS
SHOULD BEGIN TO DISSIPATE. FCST SOUNDINGS SUPPORT MAX TEMPS IN THE
UPPER 60S TO MID 70S...WARMEST SOUTH CENTRAL. WILL BE A BIT COOLER
WHERE WINDS ARE OFF LAKE SUPERIOR.
TONIGHT...SFC HIGH PRES BUILDS INTO THE WRN GREAT LAKES. HOWEVER...
SHORTWAVE TROF NOW OVER SASKATCHEWAN/MT IS FCST TO SHIFT E...
REACHING THE UPPER GREAT LAKES BY 12Z WED. SOME MODELS SHOW LIGHT
PCPN STREAKING E INTO WI AND EVEN INTO UPPER MI. INITIALLY...PCPN
DEVELOPMENT OUT OVER THE NRN PLAINS APPEARS TIED TO RIGHT ENTRANCE
OF JET STREAK ACROSS THE FAR NRN PLAINS. HOWEVER...WITH THE JET
TRANSLATING E OVER THE UPPER GREAT LAKES...JET FORCING WILL BE S OF
THE FCST AREA TONIGHT. IN ADDITION...LITTLE/NO DEEP LAYER FORCING IS
NOTED WITH SHORTWAVE...AND LOW-LEVELS ARE DRYING OUT TODAY. SO...IF
PCPN DOES MANAGE TO STREAK INTO THE AREA...THE LIGHT PCPN WOULD
LIKELY DRY UP BEFORE MAKING IT TO THE GROUND. THUS...NO MENTION OF
PCPN WAS INCLUDED IN FCST TONIGHT. AN INCREASE IN CLOUDS WILL KEEP
TEMPS FROM FALLING AS MUCH AS THEY COULD. OPTED FOR THE MIDDLE
GROUND OF AVBL GUIDANCE...RESULTING IN MIN TEMPS MOSTLY IN THE UPPER
40S/LWR 50S.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 346 AM EDT TUE AUG 26 2014
A SHORTWAVE WILL BE SLIDING EAST ACROSS THE CENTRAL/EASTERN CWA TO
START THE LONG TERM PERIOD WITHIN THE WEST-NORTHWEST FLOW ALOFT.
THERE IS A LITTLE POCKET OF MOISTURE BETWEEN 700-500MB ASSOCIATED
WITH THIS WAVE THAT WILL TRY TO KICK OFF SOME SHOWERS OVER THE
EASTERN CWA FOR THE FIRST COUPLE HOURS ON WEDNESDAY MORNING. WITH
DRY AIR BELOW 700MB DUE TO HIGH PRESSURE CENTERED NEAR DULUTH AT
12Z WEDNESDAY...THINK ANY PRECIPITATION THAT OCCURS WILL EVAPORATE
BEFORE REACHING THE SURFACE. BEHIND THIS WAVE...UPPER RIDGING WILL
DEVELOP AND ALLOW THE HIGH TO SHIFT EAST ACROSS THE CWA THROUGH
THURSDAY MORNING. THIS DRY AIR WILL LEAD TO MOSTLY CLEAR SKIES
ACROSS MUCH OF THE CWA...BUT THERE COULD BE SOME DIURNAL CLOUD
DEVELOPMENT WEDNESDAY AFTERNOON (INLAND AND TOWARDS WISCONSIN
BORDER) AFTER THE MID CLOUDS DEPART DURING THE MORNING. HIGHS WILL
BE BELOW NORMAL ON WEDNESDAY SINCE 850MB TEMPS IN THE MODELS ARE
AVERAGING AROUND 6-7C AND KEEPING HIGHS IN THE MID-UPPER 60S FOR
MOST LOCATIONS. LOWS WEDNESDAY NIGHT COULD GET CHILLY WITH THE
LIGHT WINDS...CLEAR SKIES...AND PWAT VALUES ABOUT 50 PERCENT OF
NORMAL. TRENDED LOWS DOWN INTO THE LOWER 40S OVER THE INTERIOR
LOCATIONS...AND EVEN HAVE SOME UPPER 30S FOR THE TRADITIONAL COLD
RAWS SITES.
THE AREA OF HIGH PRESSURE WILL DRIFT TO THE EAST ON THURSDAY AS THE
FIRST OF A SERIES OF SHORTWAVES LIFTS NORTHEAST OUT OF THE CENTRAL
ROCKIES/PLAINS THURSDAY AFTERNOON INTO THURSDAY NIGHT. AS HAS BEEN
THE CASE FOR THE LAST COUPLE DAYS...SEEMS LIKE BEST OPPORTUNITY FOR
RAIN WILL BE OVER THE SOUTHEAST HALF OF THE CWA. THESE SHOWERS
COULD LINGER INTO FRIDAY OVER THE SAME AREA BEFORE THE NEXT WAVE
SLIDES NORTHEAST TOWARDS THE AREA ON FRIDAY NIGHT. ONCE
AGAIN...BEST CHANCES WILL BE OVER THE SOUTHEAST PART OF THE
AREA...BUT LIKELY MORE CONFINED TO NEAR THE LAKE MICHIGAN
SHORELINE. WHILE THAT WAVE IS MOVING THROUGH...A WEAK SURFACE
TROUGH WILL SLOWLY DROP SOUTHEAST ACROSS THE CWA ON SATURDAY. THINK
PRECIP CHANCES WITH THIS PASSING TROUGH WILL BE LIMITED DUE TO
SHALLOW MOISTURE AND LIMITED UPPER LEVEL SUPPORT...THUS WILL KEEP
POPS FOR MOST AREAS IN THE SLIGHT CHANCE CATEGORY. BEHIND THAT
TROUGH...A HIGH PRESSURE RIDGE WILL MOVE OVER THE CWA SATURDAY
NIGHT AND REMAIN THROUGH SUNDAY NIGHT...AS THE PARENT HIGH SLIDES
SOUTHEAST ACROSS NORTHERN ONTARIO.
A STRONGER UPPER TROUGH WILL APPROACH THE AREA FOR THE FIRST PART
OF NEXT WEEK. A LOW PRESSURE SYSTEM ASSOCIATED WITH THIS UPPER
TROUGH WILL BE MOVING THROUGH SOUTHERN CANADA AND ALLOW SOUTHERLY
FLOW TO INCREASE OVER THE AREA SUNDAY NIGHT INTO MONDAY. THIS WILL
LEAD TO ABOVE NORMAL TEMPERATURES ON MONDAY AHEAD OF THE COLD FRONT
THAT MOVES THROUGH MONDAY NIGHT INTO TUESDAY MORNING. WILL SHOW
INCREASING CHANCES FOR RAIN MONDAY INTO MONDAY NIGHT AS THE COLD
FRONT PASSES THROUGH.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON)
ISSUED AT 122 PM EDT TUE AUG 26 2014
THERMAL TROUGH ALOFT RESULTS IN BKN MVFR TO LOWER VFR CLOUDS THIS
AFTN AT KCMX AND KSAW. PLAN ON THESE CLOUDS TO SCATTER OUT BY THE
EVENING AS RIDGING TRIES TO WORK INTO THE AREA. MID-LEVEL CLOUDS
WILL INCREASE FOR A TIME OVERNIGHT UNTIL AROUND DAYBREAK ON WEDNESDAY
AS DISTURBANCE CROSSES THE REGION. GUSTY WEST WINDS AT KCMX SHOULD
DIMINISH QUICKLY BY LATE THIS AFTN. OTHERWISE...EXPECT LIGHT WINDS
REST OF THE TAF PERIOD AT ALL TERMINALS. &&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 501 AM EDT TUE AUG 26 2014
EXPECT WESTERLY WINDS AS HIGH AS 15-25KT OVER MUCH OF LAKE SUPERIOR
TODAY...RESULTING FROM PRES GRADIENT BTWN LOW PRES WELL OFF TO THE
NE AND HIGH PRES APPROACHING FROM THE W. AS THE HIGH SETTLES OVER
THE UPPER GREAT LAKES LATER TONIGHT THRU EARLY THU...WINDS WILL DROP
OFF TO MOSTLY UNDER 15KT. ALTHOUGH THE HIGH PRES DEPARTS THU...WINDS
SHOULD REMAIN UNDER 20KT FRI/SAT EVEN WITH TROF DROPPING ACROSS THE
AREA EARLY SAT.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...ROLFSON
LONG TERM...SRF
AVIATION...JLA
MARINE...ROLFSON
AREA FORECAST DISCUSSION
NWS ST LOUIS MO
327 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 18z TAFs through 18z Wednesday Afternoon)
Issued at 1218 PM CDT Tue Aug 26 2014
Specifics for KCOU, KUIN: The outflow boundary which produced
brief periods of IFR-MVFR cigs earlier today has pushed south of
the terminals. VFR conditions are expected for the remainder of
the afternoon unless an isolated thunderstom develops during peak
heating. Overnight convection is possible at KUIN, but confidence
is too low to include in the TAF at this time.
Specifics for KSTL, KSUS, KCPS: VFR for most of the period. Will
continue to monitor for SH/TS development during peak heating due
to the outflow boundary near the St. Louis metro area terminals.
Overnight convection which is expected to develop north of the
terminals may sink farther south than currently anticipated.
Kanofsky
&&
.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 GRAND FORKS ND
1242 PM CDT TUE AUG 26 2014
.UPDATE...
ISSUED AT 1242 PM CDT TUE AUG 26 2014
THE LOW CLOUDS OVER NORTHWEST MN HAVE LIFTED INTO A STRATOCUMULUS
DECK WHICH IS STILL PRETTY THICK. WITH THE LOWER AMOUNT OF SOLAR
EXPECTED WILL GO AHEAD AND LOWER HIGH TEMPS THERE A BIT TOO.
OTHERWISE MORE CUMULUS ALSO FORMED FROM CANDO DOWN ACROSS THE
CENTRAL RED RIVER VALLEY INTO THE KPKD AREA...SO HAD TO BUMP UP
CLOUD AMOUNTS THERE TOO. SOME SHOWERS/ISOLATED THUNDER ARE ONGOING
ACROSS THE KDIK TO KBIS CORRIDOR AND THESE MAY WELL HOLD TOGETHER
AS THEY PROGRESS EASTWARD THRU THE LATER AFTERNOON. MAY HAVE TO
EXPAND THE LOW PCPN CHANCES NORTHWARD A BIT INTO THE CENTRAL RED
RIVER VALLEY IF THESE CONTINUE ON THEIR CURRENT PATH.
&&
.SHORT TERM...(TODAY THROUGH WEDNESDAY)
ISSUED AT 345 AM CDT TUE AUG 26 2014
TODAY...SURFACE HIGH PRESSURE CONTINUES TO PRESS OVER THE AREA
PRODUCING LIGHT WEST TO NORTHWEST FLOW...DRYING CONDITIONS AND
UNSEASONABLY COOL TEMPERATURES. RESIDUAL LOW CLOUDS ACROSS
NORTHERN MINNESOTA SHOULD SHIFT EASTWARD THROUGH THE MORNING AS
THE PARENT LOW PRESSURE SYSTEM CONTINUES ITS FAST BREAK ACROSS
NORTHERN ONTARIO AND JAMES BAY. EXPECT GENERALLY FAIR SKIES ACROSS
MOST OF THE AREA THROUGH MIDDAY TODAY...WITH INCREASING MIDDLE TO
LOWER LEVEL MOISTURE MOVING FROM NCNTRL SD INTO SOUTHEAST ND AND
WEST CENTRAL MN THROUGH THE LATER AFTERNOON. AN ISOLATED SHOWER OR
TWO IS POSSIBLE LATE THIS AFTERNOON ACROSS FAR SOUTHERN PORTIONS
OF THE RED RIVER BASIN. FOR NOW...THE RUC SEEMS A BIT OVERLY
AGGRESSIVE WIT THIS FEATURE...WHILE HRRR AND NAM PREFER A SOMEWHAT
STRONGER SFC HIGH PRESSURE OVER NORTHERN MINNESOTA...KEEPING MOST
OF THE PRECIP THREAT WELL TO OUR SOUTH.
TONIGHT AND WEDNESDAY...A FLAT SURFACE RIDGE STAYS DRAPED FROM
THE WESTERN GREAT LAKES...AND ACROSS NORTH DAKOTA INTO EASTERN MT.
SOUTHERLY FLOW INCREASES THROUGH THE DAY ON WEDNESDAY PROMISING
SOME REBOUNDING TEMPERATURES...WHILE DEEP MOISTURE STAYS TRAPPED
FOR ANOTHER DAY BY A STATIONARY SURFACE BOUNDARY ACROSS SOUTHERN
SD AND NRN IA.
.LONG TERM...(WEDNESDAY NIGHT THROUGH MONDAY)
ISSUED AT 345 AM CDT TUE AUG 26 2014
WEDNESDAY NIGHT AND THURSDAY...INCREASING LOW LEVEL SOUTHERLY
FLOW FROM WEDNESDAY EVENING INTO THURSDAY COULD BRING A BAND OF
MOIST AIR THROUGH EASTERN SD INTO WEST CENTRAL MN...WITH SCT
THUNDERSTORMS BRUSHING AGAINST THE SOUTHEAST EDGE OF THE RED RIVER
BASIN. HAVE STUCK WITH THE NAM AND WITH WPC CONTINUITY IN KEEPING
THE FORECAST DRY FOR THIS PERIOD WHILE THE 00Z GFS HAS BEEN
SOMETHING OF THE WET OUTLIER SOLN.
FRIDAY THROUGH MONDAY...LOW AMPLITUDE LONG WAVE TROUGH OVER THE
GULF OF AK MOVES TO CENTRAL CANADA BY THE END OF THE PERIOD.
ESSENTIALLY ZONAL FLOW REMAINS ACROSS SOUTHERN CANADA AND THE
NORTHERN STATES THROUGH THE PERIOD. ZONAL PATTERN SHIFTS SLOWLY
SOUTH BY THE END OF THE PERIOD. GFS AND ECMWF WERE IN GOOD
AGREEMENT THROUGH 84 HOURS WITH THE UPPER AIR. HOWEVER WITH THE
SURFACE FEATURES THE GFS WAS FAST AT 84 HOURS. THE GFS REMAINS
FASTER THAN THE ECMWF AT DAY 7. WILL BLEND THE ECMWF AND THE GFS.
LITTLE CHANGE TO TEMPS....INCREASES TEMPS A DEGREE OR SO FOR FRI AND
DECREASE A DEGREE OR SO FOR SAT. NO CHANGE TO SUN AND MON.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON)
ISSUED AT 1242 PM CDT TUE AUG 26 2014
EXPECT AREAS OF MVFR CUMULUS TO LIFT INTO THE VFR RANGE THIS
AFTERNOON OVER NW MN...WITH DIURNAL CUMULUS OVER THE REGION
DIMINISHING LATE TODAY. SOME MID-LEVEL CLOUD COVER WILL SPREAD INTO
E ND...WITH POSSIBLY A SHOWER AT KFAR BY LATE AFTERNOON...BUT
CONFIDENCE IS TOO LOW TO MENTION. OTHERWISE...LIGHT DAYTIME WINDS
WILL BECOME NEARLY CALM OVERNIGHT INTO EARLY WED...BEFORE SHIFTING
SOUTHERLY ON WED. WITH LIGHT WINDS OVERNIGHT...PATCHY FOG
DEVELOPMENT IS POSSIBLE...BUT WILL NOT MENTION AT THIS POINT.
&&
.FGF WATCHES/WARNINGS/ADVISORIES...
ND...NONE.
MN...NONE.
&&
$$
UPDATE...GODON
SHORT TERM...GUST
LONG TERM...GUST/HOPPES
AVIATION...MAKOWSKI